PMID- 9359752 TI - Prevalence of swine influenza and other viral, bacterial, and parasitic zoonoses in veterinarians. PMID- 9359754 TI - WHATEVER HAPPENED TO HEALERS? PMID- 9359755 TI - HOMEOPATHY counterpoint clings to old view PMID- 9359758 TI - Reinventing Primary Care PMID- 9359753 TI - Latent membrane protein 1 of Epstein-Barr virus mimics a constitutively active receptor molecule. AB - Latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) is an integral membrane protein which has transforming potential and is necessary but not sufficient for B-cell immortalization by EBV. LMP1 molecules aggregate in the plasma membrane and recruit tumour necrosis factor receptor (TNF-R) -associated factors (TRAFs) which are presumably involved in the signalling cascade leading to NF-kappaB activation by LMP1. Comparable activities are mediated by CD40 and other members of the TNF-R family, which implies that LMP1 could function as a receptor. LMP1 lacks extended extracellular domains similar to beta-adrenergic receptors but, in contrast, it also lacks any motifs involved in ligand binding. By using LMP1 mutants which can be oligomerized at will, we show that the function of LMP1 in 293 cells and B cells is solely dependent on oligomerization of its carboxy-terminus. Biochemically, oligomerization is an intrinsic property of the transmembrane domain of wild-type LMP1 and causes a constitutive phenotype which can be conferred to the signalling domains of CD40 or the TNF-2 receptor. In EBV, immortalized B cells cross-linking in conjunction with membrane targeting of the carboxy-terminal signalling domain of LMP1 is sufficient for its biological activities. Thus, LMP1 acts like a constitutively activated receptor whose biological activities are ligand-independent. PMID- 9359756 TI - a fresh start: oam charts its course for the future AB - The National Institutes of Health Office of Alternative Medicine Program Advisory Council (AMPAC) met on September 19D20, 1995, in Rockville, Md. The following report summarizes information presented at that meeting in written materials and oral reports. PMID- 9359759 TI - KARGA PUJA: A TRANSPERSONAL RITUAL OF HEALING IN TAMANG SHAMANISM AB - The karga healing ritual of the Tamang shamans is a dramatic event and a successful means of treating the major indigenous categories of mental illness, that is, soul loss and spirit possession, when they occur simultaneously in a patient. This clinical pathology is a cross-cultural variation of the categories of dissociative trance disorder and somatoform disorder described in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders of the American Psychiatric Association. Tamang shamans treat this relatively neurotic syndrome by evoking transpersonal experiences that are psychotherapeutic in that they alter the patient's relationships both in regard to the spiritual cosmos and to significant interpersonal relationships. Karga rituals evoke experiences analogous to "spiritual emergencies" and "rites of passage" with a death-and rebirth scenario leading to psychological, social, familial, and spiritual renewal. Discussion is illustrated by a case vignette. PMID- 9359761 TI - Whose Culture, Whose Body, Whose Healing? PMID- 9359760 TI - a Medical Food-Supplemented Detoxification Program in the Management of Chronic Health Problems AB - Objective * To evaluate the effectiveness of a medical food-supplemented detoxification program versus a hypoallergenic, calorie-controlled diet alone in the management of symptoms in chronically ill patients. Design * Outcome-focused study of patient response to dietary interventions. Setting * Clinical outpatient research facility. Patients * 106 chronically ill patients. Intervention * A medical food supplement designed to provide nutritional support for gastrointestinal healing and hepatic detoxification in addition to an oligoantigenic, calorie-controlled diet, versus an oligoantigenic, calorie controlled diet alone. Results * The 84 patients in the experimental group, who consumed the medical food supplement, had a 52% reduction in symptoms over 10 weeks as measured by the Metabolic Screening Questionnaire. In comparison, the 22 patients on the control diet had only a 22% reduction of symptoms. Symptom reduction in the intervention group occurred concomitantly with the normalization of hepatic phase I cytochrome P450 activity in relation to phase II glycine conjugation detoxification function measured before and after intervention. The intervention group also had a statistically significant increase in urinary sulfate-to-creatinine ratio after treatment, suggesting improved reserves of sulfur-conjugating nutrients and glutathione status. Enhanced nutrient absorption after intervention was implied by the increased absorption and urinary excretion of mannitol after the 10 weeks of therapy, although the results were only marginally significant. Conclusions * These results suggest that this supplemental medical food program may provide an important adjunctive therapy for the management of many complex symptoms associated with the chroni PMID- 9359762 TI - ALTERNATIVE MEDICINE: WHO DECIDES? PMID- 9359763 TI - Disagree with editorial on double-blind method PMID- 9359765 TI - Program Advisory Council Offers OAM Agenda PMID- 9359764 TI - A journal and a journey. PMID- 9359766 TI - Planetree: changing the way we think about patients. PMID- 9359767 TI - Training in alternatives: the next revolution in medicine. PMID- 9359768 TI - Dietary Supplement Health and Education Act: quiet but far-reaching consequences. PMID- 9359769 TI - A Cross-Cultural Comparison of Four Healing Models AB - Although Western medicine has tended to ignore other systems of preventing and treating disease and illness, practitioners of these systems serve more of the world's population than do allopathic practitioners. This paper contrasts allopathy with Chinese medicine, curanderismo, and a Native American healing system, using a 12-facet model. It points out the importance of knowing about alternative models of healing, especially in regard to religious and spiritual problems, in a multicultural society. PMID- 9359770 TI - The integration of natural healing procedures into research and teaching at German universities. AB - This article describes the activities of the "Munchener Modell," a project for "Integration of Natural Healing Procedures into Research and Teaching" at the Ludwig-Maximilian University in Munich. Its objective is to improve research and teaching of Natural Healing Procedures (NHPs) and to provide the infrastructural and conceptual prerequisites for the establishment of an independent academic institution. In the years 1989 to 1992 the project organized three 1-year pregraduate courses of NHPs for medical students. Parts of the courses have now been integrated in the regular undergraduate education. In 1993 a quality assurance project for postgraduate education was piloted. In a network of clinics using NHPs a comprehensive quality assurance project including observational studies and controlled clinical trials has been implemented and piloted. For evaluating the actual state of knowledge in a transparent way the project performs systematic reviews of published research. Further clinical-experimental research is being done in the area of immunomodulation with natural products. PMID- 9359771 TI - Developments in the analysis and evaluation of chiropractic methodologies. PMID- 9359772 TI - Chinese traditional medicine: an introductory overview. PMID- 9359773 TI - Cultural and social perspectives on alternative medicine: background and assumptions. PMID- 9359774 TI - Energy Medicine and the Unifying Concept of Information AB - Alternative medicine remains alternative because it poses serious challenges to the mainstream biomedical paradigm of mechanical reductionism and because it requires a new framework. This paper explores some of the hypotheses and challenges of energy medicine including healer interventions, electromagnetic therapies, and homeopathy. Together with new findings from the bioelectromagnetic field, they spell out the rudiments of a new paradigm for biology and medicine based on information. Information embraces the complex network of relations in the matter and energy transactions of living systems. It offers a unified view of energy medicine modalities as well as a fresh perspective for biology and medicine and new questions for further research. PMID- 9359775 TI - Homeopathic medicine. PMID- 9359776 TI - Toward a 21st century bioethic. PMID- 9359777 TI - How should alternative therapies be evaluated? An examination of fundamentals. PMID- 9359778 TI - Abstract illustrates difficulty of research design. PMID- 9359779 TI - The healing highway: alternative health and the Internet. PMID- 9359780 TI - Arizona Center for Health and Medicine: a model of integrated healthcare. PMID- 9359781 TI - Careful research of psychedelics resumes. PMID- 9359782 TI - Psychoneuro-nutritional medicine: an advancing paradigm. AB - Recent research has led to the evolution of an important clinical relationship among psychology, neurobiochemistry, and nutrition. The result has been the development of the multidisciplinary field of psychoneuro-nutritional medicine. The successful application of this medical model to mental health problems ranging from behavior disorders in children to cognitive/emotional disorders in adults has opened the door to new lower-technology, cost-effective approaches to improving functional neurobiochemistry. This review describes the psychoneuro nutritional medicine model and its application to a variety of biobehaviorally related health problems. PMID- 9359783 TI - Complementary medicine: transforming influence or footnote to history? PMID- 9359784 TI - Research methodology in psychoneuroimmunology: rationale and design of the IMAGES P clinical trial. AB - Although mental imagery has historically been ignored by the scientific community, it is one of the six most commonly used alternative therapies chosen by cancer patients. Investigations of immune response to psychosocial interventions have been largely anecdotal or quasi-experimental. Although reports of increased survival predominate among cancer patients, few investigators have measured psychological or immunological outcomes to explain the mechanisms that contribute to improved survival. The efficacy of imagery or support groups in patient adaptation (emotionally and physically) to the stresses of cancer, heightened immune function, and improved morbidity and mortality remain uncertain in the absence of objective evidence from randomized, controlled clinical trials. The imagery and group emotional support study pilot (IMAGES-P) is a 12-month feasibility study designed to examine the effect of group support and imagery/relaxation in a randomized, controlled clinical trial, differentiating the effects of these therapy modalities on immune function, quality of life, and the emotional well-being of women who have completed treatment for breast cancer. Secondary aims are to explore the quantitative relationships among emotional well being, quality of life, and immune function. For this study established clinical trial methodology was used to examine functional immune responses associated with emotional states induced by the therapy interventions. As a pilot study, IMAGES-P will provide direction for future longitudinal studies evaluating the effectiveness of these interventions on emotional well-being and survival. PMID- 9359785 TI - Storytelling as therapy: implications for medicine. AB - Storytelling is an art developed during the beginning of human history, probably to teach the wisdom of generations past, including basic mental and physical health principles. This approach, based on sound behavioral medicine principles, is explored here for use as an integral part of medical practice. Also, practical considerations are addressed concerning the conduct of storytelling, with emphasis on relaxation, imagery, and lifestyle change implementations. PMID- 9359786 TI - EDTA chelation therapy should be more commonly used in the treatment of vascular disease. AB - EDTA chelation therapy is safe, effective, and more economical than commonly used surgical treatments for vascular disease. This article includes evidence of effectiveness, mechanisms of action of EDTA, a discussion of studies that have been done regarding the therapy, and some brief case reports. The conclusion is that EDTA chelation therapy should be a therapeutic option for vascular disease, either by itself or in conjunction with standard protocols. PMID- 9359787 TI - What does illness mean? PMID- 9359788 TI - more foreign journals for abstracts section PMID- 9359790 TI - Chiropractic article ignored neurological aspects PMID- 9359789 TI - Psychedelics article was excellent; a clarification is necessary. PMID- 9359791 TI - OAM Methodology Conference II Report: WORKING GROUPS, RESEARCH PRESENTATIONS PMID- 9359792 TI - Mind-body medicine center reaches out to Washington, DC community. PMID- 9359793 TI - Mind-Body Medicine Center Reaches Out to washington, dc Community PMID- 9359794 TI - The physician and unconventional medicine. AB - BACKGROUND: Unconventional medical therapies, that is, health interventions not normally taught in medical school, consume more than $10 billion per year; yet, little is known of physician involvement with these therapies. METHOD: A national mailed survey of primary care internists with single board certification and of board-certified family physicians was undertaken to determine physician attitude and behavior toward unconventional therapies. The survey identified 16 unconventional therapies. RESULTS: A total of 572 responses were analyzed. These indicated that more than half of these physicians would encourage patients who raise the possibility of unconventional therapy. A large proportion (57%) were willing to refer their patients for treatment for six or more unconventional therapies. CONCLUSIONS: This study indicates considerable physician interest and participation in unconventional medicine, suggesting a need for research and education to help them guide their patients. PMID- 9359795 TI - Meeting of minds in psychiatry and homeopathy: an example in social phobia. AB - Communication between homeopaths and the biomedical community can be enhanced by an interpretation of the homeopathic repertory in light of current medical diagnostic terminology. This report reviews the current, conventional symptom formulation for social phobia, the third most common psychiatric diagnosis in the US community. Eighty-three rubrics in the homeopathic materia medica corresponding to symptoms of social phobia were identified and then used in a computerized repertorizing program to identify potential homeopathic remedies for social phobia. Although Kent's Repertory describes many symptoms of social phobia, the terminology should be updated, and there is a surprising lack of information about some key rubrics. Clinical judgment is always needed to interpret the significance of symptoms that could be caused by more than one pathogenic mechanism. Although many of the remedies traditionally thought to be useful in treating patients with social phobia do indeed appear in the computerized Repertory search, additional remedies emerged, including both polycrests and small remedies, which may have a place in treating this disorder. PMID- 9359796 TI - The interconnectivity of mind, brain, and behavior in altered states of consciousness: focus on shamanism. AB - This paper examines possible interconnections between mind, brain, and behavior in the area of shamanism and altered states of consciousness. It offers a neurophysiological theory of shamanic altered states of consciousness that integrates theories by Mandell, Persinger, Prince, Winkelman, and Wright. Topics include the shamanic call and temporal lobe phenomena, possible neurological correlates of shamanic ecstasy, and the neurophysiological roles of endorphins, plant substances, and genetic factors in shamanic altered states of consciousness. The difficulty of developing such a theory because of the complexity of human physiology and psychological experience and because of the paucity of neurophysiological data from the field is acknowledged. PMID- 9359797 TI - Nursing's caring-healing paradigm as exemplar for alternative medicine? AB - This article provides an overview of the crisis in modern (biomedical) and postmodern (human) science and method. Nursing's evolving system of caring and healing, within a unitary-transformative context, is offered as an exemplar to the growing field of alternative medicine. This framework for viewing alternative medicine paradigms and problems unveils some converging worldview assumptions that transcend nursing and have relevance to all caring-healing practices. PMID- 9359798 TI - What's in a word? PMID- 9359799 TI - Alternative therapies in Japan: a prototype for conquering 'karoshi' and stress. PMID- 9359801 TI - Double-blind method assumes what it denies PMID- 9359800 TI - Who gets sick and who gets well? PMID- 9359802 TI - Article on homeopathy history debated. PMID- 9359803 TI - OAM-funded programs at Bastyr, Minneapolis provide updates. PMID- 9359804 TI - The democratization of expertise: information-sharing on the Internet. PMID- 9359806 TI - The safety of herbal medicine. PMID- 9359805 TI - Ron Anderson, MD--nurturing a holistic environment at Parkland Memorial Hospital. PMID- 9359807 TI - Five-year survival rates of melanoma patients treated by diet therapy after the manner of Gerson: a retrospective review. AB - OBJECTIVE: Compare 5-year melanoma survival rates to rates in medical literature. DESIGN: Retrospective. SETTING: Hospital in Tijuana, Mexico. PATIENTS: White adult patients (N = 153) with superficial spreading and nodular melanoma, aged 25 72 years. INTERVENTION: Gerson's diet therapy: lactovegetarian; low sodium, fat and (temporarily) protein; high potassium, fluid, and nutrients (hourly raw vegetable/fruit juices). Metabolism increased by thyroid; calorie supply limited to 2600-3200 calories per day. Coffee enemas as needed for pain and appetite. MAIN OUTCOME MEASURE: 5-year survival rates by stage at admission. RESULTS: Of 14 patients with stages I and II (localized) melanoma, 100% survived for 5 years, compared with 79% of 15,798 reported by Balch. Of 17 with stage IIIA (regionally metastasized) melanoma, 82% were alive at 5 years, in contrast to 39% of 103 from Fachklinik Hornheide. Of 33 with combined stages IIIA + IIIB (regionally metastasized) melanoma, 70% lived 5 years, compared with 41% of 134 from Fachklinik Hornheide. We propose a new stage division: IVA (distant lymph, skin, and subcutaneous tissue metastases), and IVB (visceral metastases). Of 18 with stage IVA melanoma, 39% were alive at 5 years, compared with only 6% of 194 from the Eastern Cooperative Oncology Group. Survival impact was not assessed for stage IVB. Male and female survival rates were identical for stages I-IIIB, but stage IVA women had a strong survival advantage. CONCLUSIONS: The 5-year survival rates reported here are considerably higher than those reported elsewhere. Stage IIIA/B males had exceptionally high survival rates compared with those reported by other centers. PMID- 9359808 TI - Art as a healing force. PMID- 9359809 TI - Can Western science provide a foundation for acupuncture? AB - Acupuncture and other complementary medical modalities that involve holistic principles challenge the dominant biomedical paradigm of mechanical reductionism and therefore are considered unconventional or alternative. This keynote presentation will review three different hypotheses of acupuncture, two of which lie within the dominant scientific paradigm, and a third that is built upon frontier ideas at the edge of the new science of bioelectromagnetics. The Zhang Popp hypothesis, based on endogenous electromagnetic fields of the body, is capable of accommodating many puzzling features of acupuncture. In order to embody the latter, it appears that a new paradigm for the life sciences is needed to address the wholeness and integrity of the organism. Nonetheless, I believe that there are serious limitations in attempting to embrace the indigenous knowledge system of the East, one of the oldest systems of empirical knowledge, by a 300-year-old science of the West, because of their vast differences in biophilosophies and cultural orientations. All knowledge systems, East or West, are context-dependent; none can represent true objectivity. Despite this pluralistic view, working toward a unity of Eastern and Western thought may lead to a more universal understanding of acupuncture in the future. PMID- 9359810 TI - Homeopathy should be integrated into mainstream medicine. PMID- 9359811 TI - Diet and prostate problems. PMID- 9359812 TI - Yoga and meditation. PMID- 9359814 TI - enjoyed editorial on double-blind method, except for surgical reference PMID- 9359813 TI - Making alternative therapies everyone's issue. PMID- 9359815 TI - Congratulations on the first issue PMID- 9359816 TI - homeopathy article was interesting, informative PMID- 9359817 TI - another medical school alternative medicine course PMID- 9359818 TI - Chelation therapy is ineffective for the treatment of peripheral vascular disease. PMID- 9359819 TI - More kudos for Alternative Therapies PMID- 9359821 TI - English lord compliments editorial PMID- 9359820 TI - Mission of journal unclear? PMID- 9359823 TI - any alternative therapies for diabetes? PMID- 9359822 TI - prefers 'complementary' over 'alternative' PMID- 9359825 TI - Doesn't find Advisory Board representative. PMID- 9359824 TI - need news from abroad? PMID- 9359826 TI - Homeopathy does not work. PMID- 9359828 TI - Protein kinase C-dependent and Ca2+-dependent mechanisms of secretion from streptolysin O-permeabilized platelets: effects of leakage of cytosolic proteins. AB - Human platelets containing dense granules labelled with 5-hydroxy[14C]tryptamine ([14C]5-HT) were permeabilized by exposure to streptolysin O (SLO) in the presence of 4 mM [gamma-32P]ATP. Addition of either 100 nM phorbol 12-myristate 13-acetate (PMA) or of Ca2+ (pCa 5) at the same time as SLO induced secretion of dense-granule [14C]5-HT and the phosphorylation of pleckstrin by protein kinase C (PKC). Ca2+ also induced phosphorylation of myosin P-light chains. Guanosine 5' [gamma-thio]triphosphate (GTP[S], 100 microM) did not stimulate secretion from SLO-permeabilized platelets in the absence of Ca2+ (pCa>9), but greatly potentiated secretion in the presence of low PMA (10 nM) or low Ca2+ (pCa 6). However, GTP[S] did stimulate myosin P-light-chain phosphorylation in the absence of Ca2+, an effect that was associated with morphological changes, including granule centralization. Inhibition of PKC and of pleckstrin phosphorylation by Ro 31-8220 blocked secretion induced by PMA or by GTP[S] and PMA in the absence of Ca2+, but did not prevent the GTP[S]-induced phosphorylation of myosin P-light chains or secretion induced by Ca2+ at pCa 5. When the time period between exposure of platelets to SLO and challenge at pCa>9 with PMA or with GTP[S] and PMA was increased, there were rapid and parallel decreases in the secretion and pleckstrin phosphorylation responses, which were lost after 3-5 min. In contrast, the responsiveness of secretion to Ca2+ (pCa 5) or to GTP[S] and Ca2+ (pCa 6) persisted for at least 10 min after exposure of platelets to SLO, although the ability of pleckstrin to undergo phosphorylation was still lost after 3-5 min. Both PKC and pleckstrin were undetectable within platelets after 5 min exposure to SLO. The results suggest that the loss of responsiveness to PMA or to GTP[S] and PMA is attributable to the leakage of PKC (and possibly pleckstrin) from the platelets, whereas secretion stimulated by Ca2+ or by GTP[S] and Ca2+ utilizes membrane-associated Ca2+- and GTP-binding proteins and occurs independently of PKC activation. PMID- 9359827 TI - The DNA damage-recognition problem in human and other eukaryotic cells: the XPA damage binding protein. AB - The capacity of human and other eukaryotic cells to recognize a disparate variety of damaged sites in DNA, and selectively excise and repair them, resides in a deceptively small simple protein, a 38-42 kDa zinc-finger binding protein, XPA (xeroderma pigmentosum group A), that has no inherent catalytic properties. One key to its damage-recognition ability resides in a DNA-binding domain which combines a zinc finger and a single-strand binding region which may infiltrate small single-stranded regions caused by helix-destabilizing lesions. Another is the augmentation of its binding capacity by interactions with other single stranded binding proteins and helicases which co-operate in the binding and are unloaded at the binding site to facilitate further unwinding of the DNA and subsequent catalysis. The properties of these reactions suggest there must be considerable conformational changes in XPA and associated proteins to provide a flexible fit to a wide variety of damaged structures in the DNA. PMID- 9359829 TI - Analysis of the N-terminal binding domain of Go alpha. AB - Signalling from membrane receptors through heterotrimeric G-proteins (G alpha and G beta gamma) to intracellular effectors is a highly regulated process. Receptor activation causes exchange of GTP for GDP on G alpha and dissociation of G alpha from G beta gamma. Both subunits remain membrane-associated and interact with a series of other molecules throughout the cycle of activation. The N-terminal binding domain of G alpha subunits interacts with the membrane by several partially defined mechanisms: the anchoring of G alpha to the more hydrophobic G beta gamma subunits, the interaction of N-terminal lipids (palmitate and/or myristate) with the membrane, and attachment of amino acid regions to the membrane {amino acids 11-14 of Go alpha (D[11-14]); Busconi, Boutin and Denker (1997) Biochem. J. 323, 239-244}. We characterized N-terminal mutants of Go alpha with known G beta gamma-binding properties for the ability to interact with phospholipid vesicles and membranes prepared from cultured cells (acceptor membranes). In vitro analysis allows membrane interactions that are important to the activated and depalmitoylated state of G alpha to be characterized. Subcellular localization was also determined in transiently transfected COS cells. All of the mutant proteins are myristoylated, and differences in myristoylation do not account for changes in membrane binding. Disrupting the N terminal alpha-helix of Go alpha with a proline point mutation at Arg-9 (R9P) does not affect interactions with G beta gamma on sucrose-density gradients but significantly reduces acceptor membrane binding. Deletion of amino acids 6-15 (D[6-15]; reduced G beta gamma binding) or deletion of amino acids 3-21 (D[3 21]); no detectable G beta gamma binding) further reduces acceptor membrane binding. When expressed in COS cells, R9P and D[6-15] are localized in the membrane similar to wild-type Go alpha as a result of the contribution from palmitoylation. In contrast, D[3-21] is completely soluble in COS cells, and no palmitoylation is detected. The binding of Go alpha and mutants translated in vitro to liposomes indicates that Go alpha preferentially binds to neutral phospholipids (phosphatidylcholine). R9P and D[11-14] bind to phosphatidylcholine liposomes like Go alpha, but D[6-15] exhibits no detectable binding. Taken together, these studies suggest that interactions of the N-terminus of G alpha subunits with the membrane may be affected by both membrane proteins and lipids. A detailed understanding of G alpha-membrane interactions may reveal unique mechanisms for regulating signal transduction. PMID- 9359830 TI - Cloning and overexpression of rat kidney biliverdin IX alpha reductase as a fusion protein with glutathione S-transferase: stereochemistry of NADH oxidation and evidence that the presence of the glutathione S-transferase domain does not effect BVR-A activity. AB - Native biliverdin IX alpha reductase (BVR-A) is a monomer of molecular mass 34 kDa. We have developed an expression vector that allows the isolation of 40 mg of a glutathione S-transferase (GST)-BVR-A fusion protein from 1 litre of culture. The fusion protein (60 kDa) behaves as a dimer on gel filtration (120 kDa), so that we have artificially created a BVR-A dimer. The recombinant rat kidney enzyme exhibits pre-steady-state 'burst' kinetics that show a pH dependence similar to that already described for ox kidney BVR-A. Similar behaviour was obtained in the presence and absence of the GST domain both for the burst kinetics and during initial-rate studies in the presence and absence of albumin. The stereospecificity of the BVR-A-catalysed oxidation of [4-3H]NADH, labelled at the A and B faces, was shown to occur exclusively via the B face. PMID- 9359831 TI - Degradation of the inducible cAMP early repressor (ICER) by the ubiquitin proteasome pathway. AB - The inducible cAMP early repressor (ICER) is a powerful transcriptional inhibitor that plays an important role in the regulation of the cAMP-dependent transcriptional response in the neuroendocrine system. ICER activity is primarily determined by its intracellular concentration, rather than by post-translational modifications, such as phosphorylation. We investigated the mechanisms that regulate the levels of ICER transcript and polypeptides in cardiocytes, myogenic (C2C12) and pituitary-derived (GH3) cell lines. We show that in primary cardiocytes and GH3 cells ICER was inducible by cAMP but not by membrane depolarization. Moreover, lactacystin, a specific proteasome inhibitor, decreased the rate of ICER degradation. This effect was associated with the accumulation of ICER-ubiquitin conjugates. We conclude that the intracellular levels of ICER are controlled by the ubiquitin-proteasome pathway for protein breakdown. PMID- 9359832 TI - Stress-induced transcription of the clusterin/apoJ gene. AB - Clusterin/apoJ is an intriguing gene frequently isolated by differential screening in laboratories from different areas of molecular biology, since it is overexpressed in numerous cases of degenerative diseases such as Alzheimer's disease and scrapie. While the dramatic increase of clusterin expression in injured tissues is well established, the molecular basis of the gene induction remains unclear. In this study, we have focused our attention on the only DNA region strictly conserved between clusterin gene proximal promoters from different vertebrate classes. We show that this 14-bp DNA element is specifically recognized by the HSF1 transcription factor and can mediate heat-shock-induced transcription in transient expression assays. Conversely, the avian clusterin proximal promoter, point-mutated at the level of this element, no longer transmits heat-shock activation. These findings provide a possible explanation for the high sensitivity of clusterin expression to environmental changes and allow the classification of clusterin as an extracellular version of heat-shock protein. PMID- 9359833 TI - NMR solution conformation of heparin-derived hexasaccharide. AB - The solution conformation of homogeneous, heparin-derived hexasaccharide (residues A, B, C, D, E, F) has been investigated by using 1H-NMR spectroscopy. Intra-ring conformations have been defined by J-coupling constants and inter proton nuclear Overhauser effects (NOEs), and the orientation of one ring with respect to the other has been defined by inter-ring NOEs. NOE-based conformational modelling has been done by using the iterative relaxation matrix approach (IRMA), restrained energy minimization to refine structures and to distinguish between minor structural differences and equilibria between various intra-ring forms. All glucosamine residues B, D and F are in the 4C1 chair conformation. The uronate (A) residue is mostly represented by the 1H2 form, whereas internal iduronates (C and E) exist in equilibrium between the chair and skewed boat forms. Deviations in some NOEs indicate a minor contribution of the 2H1 form to the A ring. Glycosidic dihedral angles, which define the overall oligosaccharide conformation, were further refined by combining in vacuo energy map calculations and restrained energy minimization in explicit solvent water. Conformational stability was further assessed by subjecting NOE and IRMA-derived structures to 600 ps of unrestrained molecular dynamics in explicit solvent. PMID- 9359834 TI - Metallothionein accretion in human hepatic cells is linked to cellular proliferation. AB - The basal amounts of metallothionein (MT) and its rates of biosynthesis were compared in resting and proliferating Chang liver (CCl-13) cells. In resting cells the total amounts of the detectable isoforms MT-2 and MT-1e were approx. 1.6x10(6) and 4x10(5) molecules per cell respectively. In exponentially growing cultures the cellular contents of both isoforms increased co-ordinately approx. 4 fold and decreased again to the initial values within 48 h after entering density mediated growth arrest. As documented for MT-2 its transient accretion was attributable to a 10-fold rise in the rate of biosynthesis of this protein during the growth phase. Measurements of the relative amounts of MT-2 mRNA indicated the occurrence of a more than 50% increase within the first 12 h after subculturing of the cells, followed by a return to basal levels thereafter. These results denote a direct link between the programming of MT synthesis and proliferation and thus attest to a central housekeeping function of the MTs. PMID- 9359835 TI - Regulation of human prohormone convertase 2 promoter activity by the transcription factor EGR-1. AB - Prohormone convertases are involved in the tissue-specific endoproteolytic processing of prohormones and neuropeptide precursors within the secretory pathway. In the present study, we have isolated genomic clones comprising the 5' terminal region of the human prohormone convertase 2 (PC2) gene and established characteristics of the PC2 promoter region. The proximal promoter region is very G+C-rich and does not contain a canonical TATA box or a CAAT box. Transient expression assays with a set of human PC2 gene fragments containing progressive 5' deletions demonstrate that the proximal promoter region is capable of directing high levels of neuroendocrine-specific expression of reporter gene constructs. In addition, we show that the transcription factor EGR-1 interacts with two distinct elements within the proximal human PC2 promoter region. Transfection experiments also demonstrate that EGR-1 is able to enhance PC2 promoter activity. PMID- 9359836 TI - Molecular cloning and expression of a rat hepatic multiple inositol polyphosphate phosphatase. AB - The characterization of the multiple inositol polyphosphate phosphatase (MIPP) is fundamental to our understanding of how cells control the signalling activities of 'higher' inositol polyphosphates. We now describe our isolation of a 2.3 kb cDNA clone of a rat hepatic form of MIPP. The predicted amino acid sequence of MIPP includes an 18 amino acid region that aligned with approximately 60% identity with the catalytic domain of a fungal inositol hexakisphosphate phosphatase (phytase A); the similarity encompassed conservation of the RHGXRXP signature of the histidine acid phosphatase family. A histidine-tagged, truncated form of MIPP was expressed in Escherichia coli and the enzymic specificity of the recombinant protein was characterized: Ins(1,3,4,5,6)P5 was hydrolysed, first to Ins(1,4,5,6)P4 and then to Ins(1,4,5)P3, by consecutive 3- and 6-phosphatase activities. Inositol hexakisphosphate was catabolized without specificity towards a particular phosphate group, but in contrast, MIPP only removed the beta phosphate from the 5-diphosphate group of diphosphoinositol pentakisphosphate. These data, which are consistent with the substrate specificities of native (but not homogeneous) MIPP isolated from rat liver, provide the first demonstration that a single enzyme is responsible for this diverse range of specific catalytic activities. A 2.5 kb transcript of MIPP mRNA was present in all rat tissues that were examined, but was most highly expressed in kidney and liver. The predicted C terminus of MIPP is comprised of the tetrapeptide SDEL, which is considered a signal for retaining soluble proteins in the lumen of the endoplasmic reticulum; the presence of this sequence provides a molecular explanation for our earlier biochemical demonstration that the endoplasmic reticulum contains substantial MIPP activity [Ali, Craxton and Shears (1993) J. Biol. Chem. 268, 6161-6167]. PMID- 9359837 TI - Kinetic mechanism of the glycogen-phosphorylase-catalysed reaction in the direction of glycogen synthesis: co-operative interactions of AMP and glucose 1 phosphate during catalysis. AB - We employed our newly developed, continuous, spectrophotometric method [Sergienko and Srivastava (1994) Anal. Biochem. 221, 348-355] for measuring the glycogen phosphorylase-catalysed reaction in the direction of glycogen synthesis, utilizing varied concentrations of AMP (2-400 microM) and glucose 1-phosphate (G1P; 4 microM to 41 mM). The experimental data revealed that the enzyme catalysis exhibits sigmoidal dependence on both AMP and G1P concentrations, with Hill coefficient and EC50 values (mutually) affected by the concentrations of the above substrates. A detailed kinetic analysis of the substrate-dependent activation, as well as glucose-inhibition data, lead us to propose the following mechanistic features of the glycogen-phosphorylase-catalysed reaction. (1) The enzyme exhibits catalytic activity when two molecules of AMP and two molecules of G1P are bound to the dimeric unit. (2) The binding of one molecule of glucose (the competitive inhibitor of G1P) per dimeric unit results into a complete loss of the enzyme activity. (3) There is no restriction of binding of AMP or G1P when one of the dimeric subunits is already bound with the other ligand. For example, one or two G1P molecules can bind to the enzyme dimer when zero, one or two molecules of AMP are already bound. The magnitudes of rate and equilibrium constants for the glycogen-phosphorylase-catalysed reaction, derived from analyses of the experimental data in the light of a few selected minimal models, are presented. PMID- 9359838 TI - Inositol 1,4,5-trisphosphate receptor subtypes differentially recognize regioisomers of D-myo-inositol 1,4,5-trisphosphate. AB - The Ins(1,4,5)P3 regioisomers, Ins(1,4,6)P3 and Ins(1,3,6)P3, which can mimic the 1,4,5-arrangement on the inositol ring of Ins(1,4,5)P3, were examined for Ca2+ release by using four types of saponin-permeabilized cell possessing various abundances of receptor subtypes, with special reference to the relation of potency to receptor subtype. Ins(1,4,6)P3 and Ins(1,3,6)P3 were weak agonists in rat basophilic leukaemic cells (RBL cells), which possess predominantly subtype II receptors, with respective potencies of 1/200 and less than 1/500 that of Ins(1,4,5)P3 [the EC50 values were 0.2, 45 and more than 100 microM for Ins(1,4,5)P3, Ins(1,4,6)P3 and Ins(1,3,6)P3 respectively]. Similar rank order potencies were also evaluated for the displacement of [3H]Ins(1,4,5)P3 bound to RBL cell membranes by these regioisomers. However, they caused Ca2+ release from GH3 rat pituitary cells possessing predominantly subtype I receptors more potently; Ins(1,4,6)P3 and Ins(1,3,6)P3 evoked release at respective concentrations of only one-third and one-twentieth that of Ins(1,4,5)P3 (the EC50 values were 0.4, 1.2 and 8 microM for Ins(1,4,5)P3, Ins(1,4,6)P3 and Ins(1,3,6)P3 respectively). In COS-1 African green-monkey kidney cells, with the relative abundances of 37% of the subtype II and of 62% of the subtype III receptor, potencies of 1/40 and approx. 1/200 for Ins(1, 4,6)P3 and Ins(1,3,6)P3 respectively were exhibited relative to Ins(1,4,5)P3 (the EC50 values were 0.4, 15 and approx. 80 microM for Ins(1,4,5)P3, Ins(1,4,6)P3 and Ins(1,3,6)P3 respectively). In HL-60 human leukaemic cells, in spite of the dominant presence of subtype I receptors (71%), similar respective potencies to those seen with COS 1 cells were exhibited (the EC50 values were 0.3, 15 and approx. 100 microM for Ins(1,4,5)P3, Ins(1,4,6)P3 and Ins(1,3,6)P3 respectively). These results indicate that these regioisomers are the first ligands that distinguish between receptor subtypes; the present observations are of significance for the future design of molecules with enhanced selectivity. PMID- 9359839 TI - Regulation of human gamma-glutamylcysteine synthetase: co-ordinate induction of the catalytic and regulatory subunits in HepG2 cells. AB - We have shown that in HepG2 cells treatment with 75 microM t-butylhydroquinone (tBHQ) results in a 2.5-fold increase in glutathione concentration, as part of an adaptive response to chemical stress. In these cells the elevation in intracellular glutathione level was found to be accompanied by an increase of between 2-fold and 3-fold in the level of the 73 kDa catalytic subunit of gamma glutamylcysteine synthetase (heavy subunit, GCSh) and the 31 kDa regulatory subunit (light subunit, GCSl). Levels of GCSh and GCSl mRNA were increased by up to 5-fold in HepG2 cells in response to tBHQ. To study the transcriptional regulation of GCSl, we subcloned 6.7 kb of the upstream region of the human GCSl gene (GLCLR) from a genomic clone isolated from a P1 lymphoblastoid cell line genomic library. HepG2 cells were transfected with GLCLR promoter reporter constructs and treated with tBHQ. This resulted in an induction of between 1.5 fold and 3.5-fold in reporter activity, indicating that transcriptional regulation of GLCLR is likely to contribute to the induction of GCSl by tBHQ in HepG2 cells. Sequence analysis of the promoter region demonstrated the presence of putative enhancer elements including AP-1 sites and an antioxidant-responsive element, which might be involved in the observed induction of the GLCLR promoter. PMID- 9359840 TI - Mammalian actin-related protein 2/3 complex localizes to regions of lamellipodial protrusion and is composed of evolutionarily conserved proteins. AB - Human neutrophils contain a complex of proteins similar to the actin-related protein 2/3 (Arp2/3) complex of Acanthamoeba. We have obtained peptide sequence information for each member of the putative seven-protein complex previously described for Acanthamoeba and human platelets. From the peptide sequences we have identified cDNA species encoding three novel proteins in this complex. We find that in addition to Arp2 and Arp3, this complex contains a relative of the human (Suppressor of Profilin) SOP2Hs protein and four previously unknown proteins. These proteins localize in the cytoplasm of fibroblasts that lack lamellipodia, but are enriched in lamellipodia on stimulation with serum or platelet-derived growth factor. We propose a conserved and dynamic role for this complex in the organization of the actin cytoskeleton. PMID- 9359841 TI - Calnexin and calreticulin bind to enzymically active tissue-type plasminogen activator during biosynthesis and are not required for folding to the native conformation. AB - The roles of the endoplasmic-reticulum lectins calnexin and calreticulin in the folding of tissue-type plasminogen activator (tPA) have been investigated using an in vitro translation system that reconstitutes these processes as they would occur in the intact cell. Using co-immunoprecipitation of newly synthesized tPA with antibodies to calnexin and calreticulin, it was demonstrated that the interaction of tPA with both lectins was dependent upon tPA glycosylation and glucosidase trimming. When tPA was synthesized in the presence of semi permeabilized cells under conditions preventing complex formation with calnexin and calreticulin, the translation product had a specific plasminogenolytic activity identical with that when synthesized under conditions permitting interactions with both lectins. Furthermore, complexes of tPA bound to calnexin and calreticulin were shown to be enzymically active. These results demonstrate that calnexin and calreticulin can form a stable interaction with correctly folded tPA; however, such interactions are not required for the synthesis of enzymically active tPA. PMID- 9359842 TI - Expression and processing of vertebrate acetylcholinesterase in the yeast Pichia pastoris. AB - In the methylotrophic yeast Pichia pastoris, we expressed the rat acetylcholinesterase H and T subunits (AChEH and AChET respectively), as well as truncated subunits from rat (W553stop or AChETDelta, from which most of the T peptide was removed) and from Bungarus (V536stop, or AChENAT, or AChEDelta, reduced to the catalytic domain). We show that AChEH and AChET subunits are processed into the same molecular forms as in vivo or in transfected mammalian cells, but that lytic processes converting amphiphilic forms into non-amphiphilic derivatives appear to be more active in yeast. The production of glycophosphatidylinositol (GPI)-anchored molecules (dimers, with a small proportion of monomers) demonstrates that P. pastoris can correctly process a mammalian C-terminal GPI-addition signal. Truncated rat and Bungarus AChE molecules, which exclusively generated non-amphiphilic monomers, were released more efficiently and thus produced more AChE activity. In the hope of increasing the production of AChE, we replaced the endogenous signal peptide by yeast prepeptides, with or without a propeptide. We found that the presence of a propeptide, which does not exist in AChE, does not prevent the proper folding of the enzyme, and that it may either increase or decrease the yield of secreted AChE, depending on the signal peptide. Surprisingly, the highest yield was obtained with the endogenous signal peptide. For all combinations, the yield was 2-3 times higher for Bungarus than for rat AChE, probably reflecting differences in the folding efficiency or stability of the polypeptides. The Michaelis constant (Km), the constant of inhibition by excess substrate (Kss) and the catalytic constant (kcat) values of the recombinant AChEs obtained both in P. pastoris and in COS cells, were essentially identical with those of the corresponding natural enzymes, and the Ki values of active-site and peripheral site inhibitors (edrophonium, decamethonium, propidium) were similar. PMID- 9359843 TI - Recombinant two-iron rubredoxin of Pseudomonas oleovorans: overexpression, purification and characterization by optical, CD and 113Cd NMR spectroscopies. AB - The gene (alk G) encoding the two-iron rubredoxin of Pseudomonas oleovorans was amplified from genomic DNA by PCR and subcloned into the expression vector pKK223 3. The vector directed the high-level production of rubredoxin in Escherichia coli. A simple three-step procedure was used to purify recombinant rubredoxin in the 1Fe form. 1Fe-rubredoxin was readily converted to the 2Fe, apoprotein and cadmium forms after precipitation with trichloroacetic acid and resolubilization in the presence or absence of ferrous ammonium sulphate or CdCl2 respectively. Recombinant 1Fe and 2Fe rubredoxins are redox-active and able to transfer electrons from reduced spinach ferredoxin reductase to cytochrome c. The absorption spectrum and dichroic features of the CD spectrum for the cadmium substituted protein are similar to those reported for cadmium-substituted Desulfovibrio gigas rubredoxin [Henehan, Poutney, Zerbe and Vasak (1993) Protein Sci. 2, 1756-1764]. Difference absorption spectroscopy of cadmium-substituted rubredoxin revealed the presence of four Gaussian-resolved maxima at 207, 228, 241 and 280 nm; the 241 nm band is attributable, from Jorgensen's electronegativity theory, to a CysS-CdII charge-transfer excitation. The 113Cd NMR spectrum of the 113Cd-substituted rubredoxin contains two 113Cd resonances with chemical shifts located at 732.3 and 730 p.p.m. The broader linewidth and high frequency shift of the resonance at 730 p. p.m. indicates that the Cd2+ ion is undergoing chemical exchange and, consistent with the difference absorption spectra, is bound less tightly than the Cd2+ ion, giving rise to the chemical shift at 732.3 p.p.m. PMID- 9359844 TI - Species-specific alternative splicing generates a catalytically inactive form of human hormone-sensitive lipase. AB - Hormone-sensitive lipase (HSL) catalyses the rate-limiting step of adipose tissue lipolysis. The enzyme is also expressed in steroidogenic tissues, mammary gland, muscle tissues and macrophages. A novel HSL mRNA termed hHSL-S, 228 bp shorter than the full-length HSL mRNA, was detected in human adipocytes. hHSL-S mRNA results from the in-frame skipping of exon 6, which encodes the serine residue of the catalytic triad. The corresponding 80 kDa protein was identified in human adipocytes after immunoprecipitation. The truncated protein expressed in COS cells showed neither lipase nor esterase activity but was phosphorylated by cAMP dependent protein kinase. hHSL-S mRNA was found in all human tissues expressing HSL, except brown adipose tissue from newborns. It represented approx. 20% of total HSL transcripts in human subcutaneous adipocytes. No alternative splicing was detected in other mammals. Human and mouse three-exon HSL minigenes transfected into primate and rodent cell lines reproduced the splicing pattern of the endogenous HSL genes. Analysis of hybrid human/mouse minigenes transfected into human cell lines showed that cis-acting elements responsible for the skipping of human exon 6 were restricted to a 247 bp region including exon 6 and the first 19 nt of intron 6. Moreover, divergence in exonic splicing elements between mouse and human was shown to be critical for the species-specific alternative splicing. PMID- 9359845 TI - N-terminal stretch Arg2, Arg3, Arg4 and Arg5 of human lactoferrin is essential for binding to heparin, bacterial lipopolysaccharide, human lysozyme and DNA. AB - Human lactoferrin (hLF), a protein involved in host defence against infection and excessive inflammation, interacts with heparin, the lipid A moiety of bacterial lipopolysaccharide, human lysozyme (hLZ) and DNA. To determine which region of the molecule is important in these interactions, solid-phase ligand binding assays were performed with hLF from human milk (natural hLF) and N-terminally deleted hLF variants. Iron-saturated and natural hLF bound equally well to heparin, lipid A, hLZ and DNA. Natural hLF lacking the first two N-terminal amino acids (Gly1-Arg2) showed reactivities of one-half, two-thirds, one-third and one third towards heparin, lipid A, hLZ and DNA respectively compared with N terminally intact hLF. A lack of the first three residues (Gly1-Arg2-Arg3) decreased binding to the same ligands to one-eighth, one-quarter, one-twentieth and one-seventeenth respectively. No binding occurred with a mutant lacking the first five residues (Gly1-Arg2-Arg3-Arg4-Arg5). An anti-hLF monoclonal antibody (E11) that reacts to an N-lobe epitope including Arg5 completely blocked hLF ligand interaction. These results show that the N-terminal stretch of four consecutive arginine residues, Arg2-Arg3-Arg4-Arg5, has a decisive role in the interaction of hLF with heparin, lipid A, hLZ and DNA. The role of limited N terminal proteolysis of hLF in its anti-infective and anti-inflammatory properties is discussed. PMID- 9359847 TI - Expression, purification, and characterization of recombinant human glutamine synthetase. AB - A bacterial expression system has been engineered for human glutamine synthetase (EC 6.3.1.2) that produces approximately 60 mg of enzyme (20% of the bacterial soluble protein) and yields approx. 8 mg of purified enzyme per litre of culture. The recombinant enzyme was purified 5-fold to apparent homogeneity and characterized. It has a subunit molecular mass of approx. 45000 Da. The Vmax value obtained using a radioactive assay with ammonia and l-[G-3H]glutamic acid as substrates was 15.9 micromol/min per mg, 40% higher than that obtained in the colorimetric assay (9.9 micromol/min per mg) with hydroxylamine replacing ammonia as a substrate. Km values for glutamate were 3.0 mM and 3.5 mM, and for ATP they were 2.0 mM and 2. 9 mM for the radioactive and spectrophotometric assays respectively. The Km for ammonia in the radioactive assay was 0.15 mM. The midpoint of thermal inactivation was 49.7 degrees C. Hydroxylamine, Mg(II) and Mg(II)-ATP stabilized the enzyme against thermal inactivation, whereas ATP promoted inactivation. The pure enzyme is stable for several months in storage and provides a source for additional studies, including X-ray crystallography. PMID- 9359846 TI - Role of G-protein beta gamma subunits in the augmentation of P2Y2 (P2U)receptor stimulated responses by neuropeptide Y Y1 Gi/o-coupled receptors. AB - Neuropeptide Y (NPY) significantly potentiates the constrictor actions of noradrenaline and ATP on blood vessels via a pertussis toxin (PTX)-sensitive mechanism involving Gi/o (alpha beta gamma) protein subunits (Gi/o, GTP-binding proteins sensitive to PTX). In Chinese hamster ovary K1 (CHO K1) cells expressing specific receptors for these neurotransmitters, stimulation of Gi/o protein coupled receptors for NPY and other neurotransmitters can augment the Gq/11 coupled (Gq/11, GTP-binding proteins insensitive to PTX) alpha 1B adrenoceptor- or ATP receptor-induced arachidonic acid (AA) release and inositol phosphate (IP) production (early events which may precede vasoconstriction). In this study, we have assessed the role of G beta gamma subunits in the synergistic interaction between Gi/o- (NPY Y1, 5-hydroxytryptamine 5-HT1B, adenosine A1) and Gq/11- [ATP P2Y2 (P2U)]-coupled receptors on AA release by using the specific abilities of regions of the beta-adrenergic receptor kinase (beta ARK1 residues 495-689) and the transducin alpha subunit to associate with G-protein beta gamma subunit dimers and to act as G beta gamma subunit scavengers. Transient expression of beta ARK1(495-689) in CHO K1 cells heterologously expressing NPY Y1 receptors had no significant effect on the PTX-insensitive ability of ATP to stimulate AA release. Stimulation of NPY Y1 receptors (as well as the endogenous 5 hydroxytryptamine 5-HT1B receptor and the transiently expressed human adenosine A1 receptor) resulted in a PTX-sensitive augmentation of ATP-stimulated AA release, which was inhibited by expression of both G beta gamma subunit scavengers. Expression of beta ARK1(495-689) similarly inhibited NPY Y1 receptor augmentation of ATP-stimulated IP production (a measure of phospholipase C activity), a step thought to precede the NPY Y1 receptor-augmented protein kinase C-dependent AA release previously observed in these cells. These experiments demonstrate that G beta gamma subunits, as inhibited by two different G beta gamma scavengers, significantly contribute to the synergistic interaction between NPY Y1 Gi/o- and Gq/11-coupled receptor activity, and are required for the augmentation of IP production and AA release observed in this model cell system. PMID- 9359848 TI - A novel pathway for the conversion of homocysteine to methionine in eukaryotes. AB - Activation of amino acid homocysteine was compared with that of methionine in rabbit crude liver extracts and purified multi-enzyme complex of aminoacyl-tRNA synthetases. Activation was studied by measuring the incorporation of radioactive amino acid into unlabelled trichloroacetic-acid insoluble materials in the absence of protein synthesis. Homocysteine synthetase activity was found in the crude extract and in the purified multi-enzyme complex of aminoacyl-tRNA synthetases. On a molar basis, the activation of methionine by the crude extract was five times higher than the activation of homocysteine. There was a partial loss of Hcy-tRNA synthetase activity in the purified multi-enzyme complex. Preliminary reconstitution experiments indicated a requirement for an additional factor for Hcy-tRNA synthetase activity. TLC of the amino acid released from tRNA charged with [14C]homocysteine, revealed radioactivity in homocysteine, methionine and homocysteine thiolactone, indicating a conversion of tRNA-attached homocysteine to methionine. Total tRNA was separated on a benzoylated cellulose column into a fraction enriched in initiator tRNA and a methionine-accepting, but initiator tRNA-deficient, fraction. Homocysteine-accepting activity was present only in the initiator tRNA-enriched fraction. Based on the above data we propose that homocysteine activation in reticulocyte lysates, reported previously, also occurs in liver. Activated homocysteine is attached to initiator tRNA and then converted to methionine by a methylating enzyme. In the absence of methylation, tRNA-attached homocysteine is hydrolysed to produce homocysteine thiolactone. PMID- 9359849 TI - Substrate specificity of the N-acetylglucosaminyl-phosphatidylinositol de-N acetylase of glycosylphosphatidylinositol membrane anchor biosynthesis in African trypanosomes and human cells. AB - De-N-acetylation of N-acetylglucosaminyl-phosphatidylinositol (GlcNAc-PI) is the second step of glycosylphosphatidylinositol (GPI) membrane anchor biosynthesis in eukaryotes. This step is a prerequisite for the subsequent mannosylation of glucosaminyl-phosphatidylinositol (GlcN-PI) which leads to mature GPI membrane anchor precursors, which are transferred to certain proteins in the endoplasmic reticulum. The substrate specificities of the GlcNAc-PI de-N-acetylase activities of African trypanosomes and human (HeLa) cells were studied with respect to the N acyl groups (R) that could be removed from a series of GlcNR-PI substrates, where R=acetyl (Ac), propionyl (Pr), butyryl (Bu), isobutyryl (iBu), pentanoyl (Pen) or hexanoyl (Hex). The data show that the trypanosomal and HeLa enzymes had similar specificities and that the turnover of GlcNR-PIs by the trypanosomal enzyme was in the order GlcNAc-PI>GlcNPr-PI>>GlcNBu - PI approximately GlcNiBu - PI approximately GlcNPen - PI>>GlcNHex - PI. The trypanosome and HeLa de-N acetylases were unable to de-N-acetylate mannosylated GlcNAc-PI intermediates, which explains why de-N-acetylation must precede mannosylation in the GPI biosynthetic pathway. PMID- 9359850 TI - Adrenergic activation of vascular endothelial growth factor mRNA expression in rat brown adipose tissue: implication in cold-induced angiogenesis. AB - Cold exposure produces adaptive hyperplasia and growth of brown adipose tissue (BAT), the major site of non-shivering thermogenesis in rodents, associated with increased angiogenesis in this tissue. Vascular endothelial growth factor (VEGF), one of the most potent angiogenic factors, was found to be expressed abundantly in BAT of the rat. When rats were exposed to cold at 4 degrees C, the VEGF mRNA level in BAT was increased by 2-3-fold in 1-4 h, but returned to the basal level within 24 h. VEGF expression in other tissues such as heart, kidney and lung did not change after cold exposure. The cold-induced increase in VEGF mRNA was abolished by surgical sympathetic denervation, but mimicked by administration of noradrenaline or a beta3-adrenoceptor agonist CL316,243, indicating the critical role of the beta-adrenergic pathway in VEGF expression in BAT. Among three isoforms of VEGF, the mRNA of a short form (VEGF120) lacking heparin-binding activity was preferentially increased after cold exposure and treatment with the adrenergic agonists. These results suggest that cold exposure activates the sympathetic nerves and leads to a rapid increase in synthesis of VEGF in BAT, which in turn stimulates the proliferation of surrounding vascular endothelial cells. PMID- 9359851 TI - Intracellular coupling of bikunin and the heavy chain of rat pre-alpha-inhibitor in COS-1 cells. AB - Pre-alpha-inhibitor is a serum protein consisting of two polypeptides: bikunin of 16 kDa, which carries an 8 kDa chondroitin sulphate chain, and heavy chain 3 (H3) of 74 kDa. The two polypeptides are linked through an ester bond between an internal N-acetylgalactosamine residue of the chondroitin sulphate chain and the C-terminal aspartic acid residue of H3. Both bikunin and H3 are synthesized by hepatocytes and become linked as they pass through the Golgi complex. H3 is synthesized with both N- and C-terminal extensions which are released during intracellular transport. To be able to analyse the assembly of pre-alpha inhibitor in detail, we have cloned and sequenced the cDNA of rat H3. Upon expression of the protein in COS-1 cells, both propeptides were found to be released. Furthermore, co-expression of H3 and bikunin resulted in the two polypeptides becoming coupled, indicating that cells other than hepatocytes may have the capacity to form chondroitin sulphate-containing links. PMID- 9359852 TI - Identification of essential histidine residues in UDP-N-acetyl-D galactosamine:polypeptide N-acetylgalactosaminyltransferase-T1. AB - UDP-N-acetyl-d-galactosamine:polypeptide N-acetylgalactosaminyltransferases (ppGaNTases) catalyse the initial step of mucin-type O-glycosylation. The activity of bovine ppGaNTase-T1 isoenzyme was inhibited by diethyl pyrocarbonate (DEPC) modification. Activity was partially restored by hydroxylamine treatment, indicating that one of the reactive residues was a histidine. The transferase was protected against DEPC inactivation when UDP-GalNAc and EPO-G, a peptide pseudo substrate PPDAAGAAPLR, were simultaneously present, while presence of EPO-G alone did not alter DEPC inactivation. However, inclusion of UDP-GalNAc alone potentiated DEPC-inhibition of the enzyme, suggesting that UDP-GalNAc binding changes the accessibility or reactivity of an essential histidine residue. Deletion of the first 56 amino acids (including one hisitidine residue) yielded a fully active secreted form of the bovine ppGaNTase-T1 enzyme. Each of the 14 remaining histidines in the enzyme were mutated to alanine, and the recombinant mutants were recovered from COS7 cells. The mutation of histidine residues His211 ->Ala and His344-->Ala resulted in recombinant proteins with no detectable enzymic activity. A significant decrease in the initial rate of GalNAc transfer to the substrate was observed with mutants His125-->Ala and His341-->Ala (1% and 6% of wild-type activity respectively). Mutation of the remaining ten histidine residues yielded mutants that were indistinguishable from the wild-type enzyme. Mutagenesis and SDS/PAGE analysis of all N-glycosylation sequons revealed that positions N-95 and N-552 are occupied by N-linked sugars in COS7 cells. Ablation of either site did not perturb enzyme biosynthesis or enzyme activity. PMID- 9359853 TI - Interleukin-1-induced nuclear factor kappa B activation is inhibited by overexpression of phospholipid hydroperoxide glutathione peroxidase in a human endothelial cell line. AB - Oxygen radicals are commonly accepted mediators in the tumour necrosis factor mediated nuclear factor kappa B (NF kappa B) signalling cascade, but evidence for their role during interleukin-1 (IL-1) signalling is lacking. To test the involvement of hydroperoxides we investigated whether IL-1-induced NF kappa B activation could be influenced by glutathione peroxidases (GPx). These enzymes remove hydroperoxides with various specificities for the hydroperoxide substrate. By overexpressing phospholipid hydroperoxide glutathione peroxidase (PHGPx), which characteristically reacts with lipophilic hydroperoxides, the roles of H2O2 and lipid hydroperoxides were assessed. A human umbilical endothelial cell line, ECV 304, was stably transfected with the genes for both PHGPx and selenophosphate synthetase (selD), which provides selenophosphate for selenoprotein biosynthesis. When grown in selenium-deficient culture medium, the double-transfected clone (ECVPHGPx+SelD+) expressed 5-fold higher (P<0.005) PHGPx activity (measured by phosphatidylcholine hydroperoxide removal) than controls. The rate of H2O2 removal was also significantly (P<0.01) higher in this clone. When grown with high levels of extracellular selenium (up to 100 nM selenite), PHGPx activity and H2O2 removal were enhanced substantially in control cells and transfected cells. Under these conditions, PHGPx activity was 1.7-fold (P<0.005) higher in ECVPHGPx+SelD+, but H2O2 removal was the same as in controls. IL-1-induced NF kappa B activation was inhibited by selenium supplementation in control cells. In ECVPHGPx+SelD+ under conditions of selenium restriction, IL-1 induced NF kappa B activation only to a similar extent as under conditions of selenium supplementation in controls, and activation was abolished with 50 nM sodium selenite. These results show that overexpressed PHGPx is sufficient to inhibit NF kappa B activation, and suggests that NF kappa B activation by IL-1 is mediated by a preferential substrate of PHGPx, such as a fatty acid hydroperoxide, rather than by H2O2, the preferred substrate of the more abundant cytosolic GPx. PMID- 9359854 TI - Short-term impairment of energy production in isolated rat liver mitochondria by hypoxia/reoxygenation: involvement of oxidative protein modification. AB - The aim of the present study was to elucidate the role of mitochondria in liver impairment after ischaemia/reperfusion. It is commonly assumed that mitochondria are in part responsible for tissue damage by impaired oxidative phosphorylation as a consequence of the attack of radicals generated within the mitochondria. The principal support for this hypothesis was found by exposing isolated mitochondria to temporary hypoxia in combination with alterations of substrate supply. Rat liver mitochondria treated in this way responded with impaired ADP-stimulated respiration after reoxygenation, which decreased with time of hypoxia and reoxygenation. The decline of the activity of the NADH-cytochrome c oxidoreductase complex found under these conditions is likely to cause the drop in active respiration. No changes in the content of respiratory chain complexes, determined by Blue Native PAGE, could be demonstrated. However, oxidative modifications of mitochondrial proteins, indicated by carbonyl formation, were found. Likewise, products of lipid peroxidation, such as lipid peroxides and malondialdehyde, were formed. Mitochondria were still able to build up a transmembrane potential and did not show drastic changes in membrane conductivity after hypoxia/reoxygenation stress. The presence of water-soluble antioxidants exhibited a beneficial effect, diminishing the decline of active respiration after 5 min of hypoxia and 10 min of reoxygenation. These observations strongly suggest that mitochondria play a pathogenic role in ischaemia/reperfusion injury, which is at least in part mediated by an oxygen-derived free-radical-linked mechanism. PMID- 9359855 TI - Location and functional characterization of myosin contact sites in smooth muscle caldesmon. AB - Caldesmon interaction with smooth muscle myosin and its ability to cross-link actin filaments to myosin were investigated by the use of several bacterially expressed myosin-binding fragments of caldesmon. We have confirmed the presence of two functionally different myosin-binding sites located in domains 1 and 3/4a of caldesmon. The binding of the C-terminal site is highly sensitive to ionic strength and hardly participates in acto-myosin cross-linking, while the N terminal binding site is relatively independent of ionic strength and apparently contains two separate myosin contact regions within residues 1-28 and 29-128 of chicken gizzard caldesmon. Both these N-terminal sub-sites are involved in the interaction with myosin and are predominantly responsible for the caldesmon mediated high-affinity cross-linking of actin and myosin filaments, without affecting the affinity of direct acto-myosin interaction. Binding of caldesmon and its fragments to myosin or rod filaments revealed affinity in the micromolar range. We determined various stoichiometries at maximal binding, which depended on the ionic strength and the concentration of Mg2+ ions. At 30 mM NaCl and 1 mM Mg2+ the maximum stoichiometry was 4 moles of caldesmon (or caldesmon fragment) per mole of myosin. At 130 mM NaCl/1 mM Mg2+, or at 30 mM NaCl/5mM Mg2+ it decreased to about two caldesmon molecules bound per myosin, while remaining 4:1 for individual caldesmon fragments, suggesting that all binding sequences on myosin were still fully capable of interaction. A further increase in the Mg2+ concentration led to a substantial decrease in both the affinity and maximum stoichiometry of caldesmon and the fragments binding to myosin. We suggest that caldesmon-myosin interaction varies according to the conformation of caldesmon in solution, that caldesmon-binding sites on myosin are not well defined and that their accessibility is determined by spatial organization and is blocked by divalent cations like Mg2+. PMID- 9359856 TI - Primary structure of a copper-binding metallothionein from mantle tissue of the terrestrial gastropod Helix pomatia L. AB - A novel copper-binding metallothionein (MT) has been purified from mantle tissue of the terrestrial snail Helix pomatia using gel-permeation chromatography, ion exchange chromatography and reverse-phase HPLC. Copper was removed from the thionein by addition of ammonium tetrathiomolybdate. The resulting apothionein (molecular mass 6247 Da) was S-methylated and digested with trypsin, endoproteinase Arg-C and endoproteinase Lys-C. Amino acid sequences of the resulting peptides were determined by collision-induced dissociation tandem MS. The protein is acetylated at its N-terminus, and consists of 64 amino acids, 18 of which are cysteine residues. A comparison with the cadmium-binding MT isolated from the midgut gland of the same species shows an identical arrangement of the cysteines, but an unexpectedly high variability in the other amino acids. The two MT isoforms differ in total length and at 26 positions of their peptide chains. We suggest that the copper-binding MT isoform from the mantle of H. pomatia is responsible for regulatory functions in favour of copper, probably in connection with the metabolism of the copper-bearing protein, haemocyanin. PMID- 9359857 TI - 14,15-Dehydroleukotriene A4: a specific substrate for leukotriene C4 synthase. AB - We studied the metabolism of 14,15-dehydro-leukotriene A4 (14, 15-dehydro-LTA4) by human platelet leukotriene C4 (LTC4) synthase and polymorphonuclear leucocyte (PMNL) leukotriene A4 (LTA4) hydrolase. Metabolites were separated and identified using reversed-phase HPLC coupled to diode-array UV detection. Human platelets metabolize 14,15-dehydro-LTA4 to 14,15-dehydro-LTC4 with apparent kinetics identical with authentic LTA4. Metabolism to 14, 15-dehydro-LTC4 is inhibited by MK-886, a reported LTC4 synthase inhibitor in human platelets, with a potency comparable with that shown by LTA4. In contrast, neither human red-blood-cell lysates nor human PMNL enzymically convert 14,15-dehydro-LTA4 into 14, 15-dehydro leukotriene B4. Minor amounts of 14,15-dehydro-LTC4, observed in some PMNL preparations, result from variable eosinophil contamination, as confirmed using highly purified neutrophil and eosinophil-enriched preparations. In addition, 14,15-dehydro-LTA4 irreversibly inhibits PMNL LTA4 hydrolase with an IC50 of 0.73 microM. The geometry of the methyl terminus of LTA4 does not influence the metabolism by human platelet LTC4 synthase. The double bond at C-14,15 is essential for the catalytic activity of LTA4 hydrolase but not for binding to this enzyme. PMID- 9359858 TI - Mutagenesis of residue 157 in the active site of human glyoxalase I. AB - Met-157 in the active site of human glyoxalase I was changed by site-directed mutagenesis into alanine, glutamine or histidine in order to evaluate its possible role in catalysis. The glyoxalase I mutants were expressed in Escherichia coli and purified on an S-hexylglutathione affinity gel. The physicochemical properties of the mutant proteins were similar to those of the wild-type enzyme. The glutamine mutant exhibited the same high specific activity as wild-type glyoxalase I, whereas the alanine and histidine mutants had approx. 20% of wild-type activity. The kcat/Km values of the mutant glyoxalase I determined with the hemithioacetal adduct of glutathione and methylglyoxal were reduced to between 10 and 40% of the wild-type value. This reduction was due to lower kcat values for the alanine and histidine mutants and a twofold increase in the Km value for the glutamine mutant. With the hemithioacetal of glutathione and phenylglyoxal, the kinetic parameters of the mutants were also of the same magnitude as those of wild-type glyoxalase I. Studies with the competitive inhibitors S-hexyl- and S-benzyl-glutathione revealed that the affinity was reduced to 7-11% of the wild-type affinity for the glutamine and alanine mutants and to 30-40% for the histidine mutant, as measured by a comparison of Ki values. The results show that Met-157 has no direct role in catalysis, but is rather involved in forming the substrate-binding site of human glyoxalase I. The high activity of the glutamine mutant suggests that a structurally equivalent glutamine residue in the N-terminal half of Saccharomyces cerevisiae glyoxalase I may be part of a catalytically competent active site. PMID- 9359859 TI - Expression of Menkes disease gene in mammary carcinoma cells. AB - Two P-type ATPases, MNK and WND were recently shown to be defective in the human disorders of copper transport, Menkes disease and Wilson disease respectively. These proteins are important in copper homeostasis but their full physiological function has not been established. This study uses the human breast carcinoma line, PMC42, to investigate copper transport in the mammary gland. Northern blot analysis indicated that both MNK and WND mRNA are expressed in these cells. Western blot analysis with an MNK-specific antibody demonstrated a band of approx. 178 kDa, close to the expected size of 163 kDa. Treatment of PMC42 cells with lactational hormones (oestrogen and progesterone for 3 days followed by dexamethasone, insulin and prolactin for a further 3 days) did not produce an obvious increase in MNK expression as measured by Northern and Western blots. By using indirect immunofluorescence with the MNK antibody, the intracellular distribution of MNK was found to be predominantly perinuclear, consistent with Golgi localization. Punctate staining was also seen in a smaller proportion of cells, suggesting that some MNK is associated with endosomes. Treatment of PMC42 cells with lactational hormones increased the intensity of the perinuclear and punctate fluorescence. Exposure of cells to 100 mM copper resulted in the dispersion of the fluorescence towards the periphery of the cell. The results suggest a role for MNK in the secretion of copper into milk and that PMC42 cells are a valuable model for investigating the detailed cellular function of MNK and WND. PMID- 9359860 TI - Characterization of alpha-conotoxin interactions with the nicotinic acetylcholine receptor and monoclonal antibodies. AB - The venoms of predatory marine cone snails, Conus species, contain numerous peptides and proteins with remarkably diverse pharmacological properties. One group of peptides are the alpha-conotoxins, which consist of 13-19 amino acids constrained by two disulphide bonds. A biologically active fluorescein derivative of Conus geographus alpha-conotoxin GI (FGI) was used in novel solution-phase binding assays with purified Torpedo californica nicotinic acetylcholine receptor (nAchR) and monoclonal antibodies developed against the toxin. The binding of FGI to nAchR or antibody had apparent dissociation constants of 10-100 nM. Structure function studies with alpha-conotoxin GI analogues composed of a single disulphide loop revealed that different conformational restraints are necessary for effective toxin interactions with nAchR or antibodies. PMID- 9359861 TI - Expression of hydrophilic surfactant proteins by mesentery cells in rat and man. AB - Human peritoneal dialysis effluent (PDE) contains a phosphatidylcholine-rich compound similar to the surfactant that lines lung alveoli. This material is secreted by mesothelial cells. Lung surfactant is also characterized by four proteins essential to its function. After having long been considered as lung specific, some of them have been found in gastric and intestinal epithelial cells. To explore further the similarity between lung and peritoneal surfactants, we investigated whether mesothelial cells also produce surfactant proteins. We used rat transparent mesentery, human visceral peritoneum biopsies and PDE. Surfactant proteins were searched for after one- and two-dimensional SDS/PAGE and Western blotting. On a one-dimensional Western blot, bands at 38 and 66 kDa in rat mesentery, and at 38 and 66 kDa in human peritoneal mesothelial cells (in vivo and in vitro) and PDE, corresponded to monomeric and dimeric forms of lung surfactant protein A (SP-A). On two-dimensional Western blots, the 32 and 38 kDa spots in mesentery and PDE localized at the acidic pH appropriate to the SP-A monomer's isoelectric point. SP-D was also identified at the same 43 kDa molecular mass as in lung. SP-B was not detected in mesenteric samples. Expression of SP mRNA species was also assessed by reverse transcriptase-PCR, which was performed with specific primers of surfactant protein cDNA sequences. With primers of SP-A and SP-D, DNA fragments of the same size were amplified in lung and mesentery, indicating the presence of SP-A and SP-D mRNA species. These fragments were labelled by appropriate probes in a Southern blot. No amplification was obtained for SP-B. These results show that mesentery cells produce SP-A and SP-D, although they are of embryonic origin (mesodermal) and are different from those of the lung and digestive tract (endodermal) that secrete these surfactants. PMID- 9359862 TI - Adenosine 5'-tetraphosphate phosphohydrolase from yellow lupin seeds: purification to homogeneity and some properties. AB - Adenosine 5'-tetraphosphate phosphohydrolase (EC 3.6.1.14) has been purified to homogeneity from the meal of yellow lupin (Lupinus luteus) seeds. The enzyme is a single polypeptide chain of 25+/-1 kDa. It catalyses the hydrolysis of a nucleoside 5'-tetraphosphate to a nucleoside triphosphate and orthophosphate, and hydrolysis of tripolyphosphate but neither pyrophosphate nor tetraphosphate. A divalent cation, Mg2+, Co2+, Ni2+ or Mn2+, is required for these reactions. The pH optimum for hydrolysis of adenosine 5'-tetraphosphate (p4A) is 8.2, Vmax is 21+/-1.7 micromol/min per mg of protein and the Km for p4A is 3+/-0.6 microM. At saturating p4A concentrations, the rate constant for the reaction is 8.5+/-0.7 s 1 [at 30 degrees C, in 50 mM Hepes/KOH (pH8.2)/5 mM MgCl2/0.1 mM dithiothreitol]. p4A and guanosine 5'-tetraphosphate are hydrolysed at the same rate. Adenosine 5' pentaphosphate (p5A) is degraded 1/200 as fast and is converted into ATP and two molecules of orthophosphate, which are liberated sequentially. This contrasts with the cleavage of p5A by the lupin diadenosine tetraphosphate hydrolase (EC 3.6.1.17), which gives ATP and pyrophosphate. Zn2+, F- and Ca2+ ions inhibit the hydrolysis of p4A with I50 values of 0.1, 0.12 and 0.2 mM respectively. PMID- 9359863 TI - Thrombin produces phosphorylation of cytosolic phospholipase A2 by a mitogen activated protein kinase kinase-independent mechanism in the human astrocytoma cell line 1321N1. AB - The release of [3H]arachidonic acid was studied in the 1321N1 astrocytoma cell line upon stimulation with thrombin. The effect of thrombin was antagonized by hirudin only when both compounds were added simultaneously, which suggests activation of thrombin receptor. Evidence that the cytosolic phospholipase A2 (cPLA2) takes part in thrombin-induced arachidonate release was provided by the finding that thrombin induced retardation of the mobility of cPLA2 in SDS/polyacrylamide gels, which is a feature of the activation of cPLA2 by mitogen activated protein (MAP) kinases. Thrombin induced activation of two members of the MAP kinase family whose consensus primary sequence appears in cPLA2, namely p42-MAP kinase and c-Jun kinase. However, the activation of c-Jun kinase preceded the phosphorylation of cPLA2 more clearly than the activation of p42-MAK kinase did. Both cPLA2 and c-Jun kinase activation were not affected by PD-98059, a specific inhibitor of MAP kinase kinases, which indeed completely blocked p42-MAP kinase shift. Heat shock, a well-known activator of c-Jun kinase, also phosphorylated cPLA2 but not p42-MAP kinase. These data indicate the existence in astrocytoma cells of a signalling pathway triggered by thrombin receptor stimulation that activates a kinase cascade acting on the Pro-Leu-Ser-Pro consensus primary sequence, activates cPLA2, and associates the release of arachidonate with nuclear signalling pathways. PMID- 9359864 TI - The sphingomyelin-ceramide pathway participates in cytokine regulation of C reactive protein and serum amyloid A, but not alpha-fibrinogen. AB - Maximal induction of the acute-phase proteins C-reactive protein (CRP) and serum amyloid A (SAA) in the human hepatoma cell line Hep3B requires the combination of interleukin (IL)-6 and IL-1. In contrast, IL-1 inhibits fibrinogen induction by IL-6. To explore the possible participation of the sphingomyelin-ceramide pathway in the transduction of cytokine effects, the role of this pathway in expression of CRP, SAA and alpha-fibrinogen was investigated. The cell-permeable ceramide analogues C2 and C6 each greatly potentiated induction of both CRP and SAA mRNA by IL-6+IL-1beta but did not affect the responses of alpha-fibrinogen to IL-6 or to IL-6+IL-1beta. The combination of IL-6+IL-1beta led to increased turnover of sphingomyelin in Hep3B cells. D609, an inhibitor of ceramide production by acidic but not neutral sphingomyelinases, substantially inhibited induction of CRP and SAA by IL-6+IL-1beta. The ability of C2 and C6 to potentiate the effects of cytokines suggests that the sphingomyelin-ceramide pathway participates in induction of CRP and SAA by IL-6+IL-1beta under these experimental conditions, most likely by transducing the effects of IL-1beta. C2 and C6 were unable to substitute for IL-1beta in enhancing IL-6 effects on CRP and SAA, consistent with other reports indicating that the sphingomyelin-ceramide pathway is only a single component of multiple necessary converging pathways for induction of many genes. In contrast, this pathway does not appear to participate in mediating the inhibitory effects of IL-1beta on fibrinogen induction by IL-6. PMID- 9359865 TI - Thioredoxin from Bacillus acidocaldarius: characterization, high-level expression in Escherichia coli and molecular modelling. AB - The thioredoxin (Trx) from Bacillus acidocaldarius (BacTrx) was purified to homogeneity by anion-exchange chromatography and gel-filtration chromatography, based on its ability to catalyse the dithiothreitol-dependent reduction of bovine insulin disulphides. The protein has a molecular mass of 11577 Da, determined by electrospray mass spectrometry, a pI of 4.2, and its primary structure was obtained by automated Edman degradation after cleavage with trypsin and cyanogen bromide. The sequences of known bacterial Trxs were aligned at the active site: BacTrx has an identity ranging from 45 to 53% with all sequences except that of the unusual Anabaena strain 7120 Trx (37% identity). The gene coding for BacTrx was isolated by a strategy based on PCR gene amplification and cloned in a plasmid downstream of a lac-derived promoter sequence; the recombinant clone was used as the expression vector for Escherichia coli. The expression was optimized by varying both the time of cell growth and the time of exposure to the inducer isopropyl beta-d-thiogalactoside; expressed BacTrx represents approx. 5% of the total cytosolic protein. CD spectra and differential scanning calorimetry measurements demonstrated that BacTrx is endowed with a higher conformational heat stability than the Trx from E. coli. Nanogravimetry experiments showed a lower content of bound water in BacTrx than in E. coli Trx, and a transition temperature approx. 10 degrees C higher for BacTrx. The three-dimensional model of the oxidized form of BacTrx was constructed by a comparative molecular modelling technique, using E. coli Trx and Anabaena strain 7120 Trx as reference proteins. Increased networks of ion-pairs and shorter loops emerged as major features of the BacTrx structure compared with those of the template proteins. The findings are discussed in the light of the current knowledge about molecular determinants of protein stability. PMID- 9359866 TI - Characterization of homocysteine metabolism in the rat kidney. AB - Epidemiological studies have provided strong evidence that an elevated plasma homocysteine concentration is an important independent risk factor for cardiovascular disease. We have shown, in the rat, that the kidney is a major site for the removal and subsequent metabolism of plasma homocysteine [Bostom, Brosnan, Hall, Nadeau and Selhub (1995) Atherosclerosis 116, 59-62]. To characterize the role of the kidney in homocysteine metabolism further, we measured the disappearance of homocysteine in isolated renal cortical tubules of the rat. Renal tubules metabolized homocysteine primarily through the transulphuration pathway, producing cystathionine and cysteine (78% of homocysteine disappearance). Methionine production accounted for less than 2% of the disappearance of homocysteine. Cystathionine, and subsequently cysteine, production rates, as well as the rate of disappearance of homocysteine, were sensitive to the level of serine in the incubation medium, as increased serine concentrations permitted higher rates of cystathionine and cysteine production. On the basis of enrichment profiles of cystathionine beta-synthase and cystathionine gamma-lyase, in comparison with marker enzymes of known location, we concluded that cystathionine beta-synthase was enriched in the outer cortex, specifically in cells of the proximal convoluted tubule. Cystathionine gamma lyase exhibited higher enrichment patterns in the inner cortex and outer medulla, with strong evidence of an enrichment in cells of the proximal straight tubule. These studies indicate that factors that influence the transulphuration of homocysteine may influence the renal clearance of this amino acid. PMID- 9359867 TI - DNA-binding protein Pur alpha and transcription factor YY1 function as transcription activators of the neuron-specific FE65 gene promoter. AB - Fe65 is an adaptor protein that interacts with the Alzheimer beta-amyloid precursor protein and is expressed mainly in the neurons of several regions of the nervous system. The FE65 gene has a TATA-less promoter that drives an efficient transcription in cells showing a neuronal phenotype, whereas its efficiency is poor in non-neuronal cells. A short sequence encompassing the transcription start site contains sufficient information to drive the transcription in neuronal cells but not in non-neural cells. Electrophoretic mobility-shift assays performed with rat brain nuclear extracts showed that three major DNA-protein complexes, named BI, BII and BIII, are formed by the FE65 minimal promoter. The proteins present in complexes BI and BII were purified from bovine brain; internal microsequencing of the purified proteins demonstrated that they corresponded to the previously isolated single-stranded-DNA-binding protein Pur alpha, abundantly expressed in the brain. In Chinese hamster ovary (CHO) cells, where the efficiency of FE65 promoter is very low, transient expression of Pur alpha increased the transcription efficiency of the FE65 minimal promoter. By using oligonucleotide competition and a specific antibody we demonstrated that the transcription factor YY1 is responsible for the formation of complex BIII. Also in this case, the transient expression of the YY1 cDNA in CHO cells resulted in an increased transcription from the FE65 minimal promoter. The absence of any co-operative effect when CHO cells were co-transfected with both YY1 and Pur alpha cDNA species suggests that two different transcription regulatory mechanisms could have a role in the regulation of the FE65 gene. PMID- 9359868 TI - Evolution of phosphagen kinase. Isolation, characterization and cDNA-derived amino acid sequence of two-domain arginine kinase from the sea anemone Anthopleura japonicus. AB - Arginine kinase (AK) was isolated from the body wall muscle of the primitive sea anemone Anthopleura japonicus by Ultrogel AcA34 gel filtration, DEAE-32 chromatography and elution on a Cosmogel-SP column. The denatured molecular mass as determined with SDS/PAGE was 80 kDa, twice that of the usual AK subunit, indicating that this AK has an unusual two-domain structure. The native form was eluted on a Superose 12 column with the same retention time as that of rabbit homodimeric creatine kinase, indicating that Anthopleura AK is a monomer of 80 kDa. The isolated enzyme gave a specific activity of 100-120 micromol of Pi/min per mg of protein in the pH range 7.9-9.1 for the forward reaction. The enzyme is fully activated by Ca2+, as it is with Mg2+. The cDNA-derived amino acid sequence of 715 residues of Anthopleura AK was determined. The validity of the sequence was supported by chemical sequencing of internal tryptic peptides. A bridge intron of 686 bp, which separates the two domains of Anthopleura AK, is present between the second and third nucleotide in the codon of Ala-364. This is the first two-domain AK to be sequenced. Anthopleura AK shows 48-54% amino acid sequence identity with known invertebrate AKs, and also shows a lower, but significant, similarity (39-46%) to marine worm glycocyamine kinase and rabbit creatine kinase. PMID- 9359869 TI - Rapid induction of apoptosis by deregulated uptake of polyamine analogues. AB - Treatment of Chinese hamster ovary cells with alpha-difluoromethylornithine for 3 days, followed by exposure to cycloheximide, led to an unregulated, rapid and massive accumulation of polyamine analogues. This accumulation led to cell death by apoptosis within a few hours. Clear evidence of DNA fragmentation was seen in response to both N-terminally ethylated polyamines and to polyamines containing methyl groups on the terminal carbon atoms. Programmed cell death was induced within 2-4 h of exposure to 1 microM or higher concentrations of N1,N11 bis(ethyl)norspermine. The presence of cycloheximide increased the uptake of the polyamine analogues and therefore led to cell death at lower analogue concentrations, but it was not essential for the induction of apoptosis, since similar effects were seen when the protein synthesis inhibitor was omitted and the concentration of N1, N11-bis(ethyl)norspermine was increased to 5 microM or more. The induction of apoptosis was blocked both by the addition of the caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone, or by the addition of the polyamine oxidase inhibitor N1-methyl-N2-(2,3-butadienyl)butane-1,4 diamine (MDL 72,527). These experiments provide evidence to support the concepts that: (1) polyamines or their oxidation products may be initiators of programmed cell death; (2) regulation of polyamine biosynthesis and uptake prevents the accumulation of toxic levels of polyamines; and (3) the anti-neoplastic effects of bis(ethyl) polyamine analogues may be due to the induction of apoptosis in sensitive tumour cells. PMID- 9359870 TI - Relaxed enantioselectivity of human mitochondrial thymidine kinase and chemotherapeutic uses of L-nucleoside analogues. AB - Our discovery that Herpes virus thymidine kinase (TK) and cellular deoxycytidine kinase lack enantioselectivity, being able to phosphorylate both D- and L enantiomers of the substrate, suggested the use of unnatural L-nucleoside analogues as antiviral drugs (Herpes, hepatitis and immunodeficiency viruses). Several L-nucleoside analogues have displayed a short-term cytotoxicity much lower than their corresponding D-counterpart. Since the delayed cytotoxicity of a drug often depends on its effects on mitochondrial metabolism, we have investigated the degree of enantioselectivity of human mitochondrial thymidine kinase (mt-TK). We demonstrate that mt-TK does not show an absolute enantioselectivity, being able to recognize, although with lower efficiency, the L-enantiomers of thymidine, deoxycytidine and modified deoxyuridines, such as (E) 5-(2-bromovinyl)-2'-deoxyuridine and 5-iodo-2'-deoxyuridine. Interestingly, the reported negative co-operativity of mt-TK phosphorylating beta-D-2' deoxythymidine (D-Thd), disappears when the deoxyribose moiety has the inverted configuration, resulting in the preferential phosphorylation of d-Thd even in the presence of high concentrations of the L-enantiomer. This, coupled with the higher Km for beta-L-2'-deoxythymidine (L-Thd), makes mt-TK resistant to high concentrations of L-Thd and L-Thd analogues, minimizing the mitochondria dependent delayed cytotoxicity that might be caused by the administration of L nucleoside analogues as antivirals. PMID- 9359871 TI - A four-disulphide-bridged toxin, with high affinity towards voltage-gated K+ channels, isolated from Heterometrus spinnifer (Scorpionidae) venom. AB - A new toxin, named HsTX1, has been identified in the venom of Heterometrus spinnifer (Scorpionidae), on the basis of its ability to block the rat Kv1.3 channels expressed in Xenopus oocytes. HsTX1 has been purified and characterized as a 34-residue peptide reticulated by four disulphide bridges. HsTX1 shares 53% and 59% sequence identity with Pandinus imperator toxin1 (Pi1) and maurotoxin, two recently isolated four-disulphide-bridged toxins, whereas it is only 32-47% identical with the other scorpion K+ channel toxins, reticulated by three disulphide bridges. The amidated and carboxylated forms of HsTX1 were synthesized chemically, and identity between the natural and the synthetic amidated peptides was proved by mass spectrometry, co-elution on C18 HPLC and blocking activity on the rat Kv1.3 channels. The disulphide bridge pattern was studied by (1) limited reduction-alkylation at acidic pH and (2) enzymic cleavage on an immobilized trypsin cartridge, both followed by mass and sequence analyses. Three of the disulphide bonds are connected as in the three-disulphide-bridged scorpion toxins, and the two extra half-cystine residues of HsTX1 are cross-linked, as in Pi1. These results, together with those of CD analysis, suggest that HsTX1 probably adopts the same general folding as all scorpion K+ channel toxins. HsTX1 is a potent inhibitor of the rat Kv1.3 channels (IC50 approx. 12 pM). HsTX1 does not compete with 125I-apamin for binding to its receptor site on rat brain synaptosomal membranes, but competes efficiently with 125I-kaliotoxin for binding to the voltage-gated K+ channels on the same preparation (IC50 approx. 1 pM). PMID- 9359872 TI - Genetic analysis of beta1 integrin function: confirmed, new and revised roles for a crucial family of cell adhesion molecules. AB - Integrins are heterodimeric cell adhesion proteins connecting the extracellular matrix to the cytoskeleton and transmitting signals in both directions. These integrins are suggested to be involved in many different biological processes such as growth, differentiation, migration, and cell death. Of more than 20 known integrins, 10 contain the nearly ubiquitously expressed beta1 integrin subunit. Disruption of the beta1 integrin gene by homologous recombination allows us to assess the supposed functions of beta1 containing integrins in vivo in a new way. This review will present and discuss recent findings derived from such studies concerning the biological roles of beta1 integrins in early development, differentiation and migration, hematopoiesis, tumorigenesis, and supramolecular assembly of extracellular matrix proteins. While several former results were confirmed, others were contradicted and new functions found, significantly changing the previous view of beta1 integrin function in vivo. PMID- 9359873 TI - Contact guidance of CNS neurites on grooved quartz: influence of groove dimensions, neuronal age and cell type. AB - We used an in vitro system that eliminates competing guidance cues found in embryos to determine whether substratum topography alone provides important neurite guidance information. Dissociated embryonic Xenopus spinal cord neurons and rat hippocampal neurons were grown on quartz etched with a series of parallel grooves. Xenopus neurites grew parallel to grooves as shallow as 14 nm and as narrow as 1 microm. Hippocampal neurites grew parallel to deep, wide grooves but perpendicular to shallow, narrow ones. Grooved substrata determined the sites at which neurites emerged from somas: Xenopus neurites sprouted from regions parallel to grooves but presumptive axons on rat hippocampal neurons emerged perpendicular to grooves and presumptive dendrites emerged parallel to them. Neurites grew faster in the favored direction of orientation and turned through large angles to align on grooves. The frequency of perpendicular alignment of hippocampal neurites depended on the age of the embryos from which neurons were isolated, suggesting that contact guidance is regulated in development. Collectively, the data indicate that substratum topography is a potent morphogenetic factor for developing CNS neurons and suggest that in addition to a role in pathfinding the geometry of the embryo assists in establishing neuronal polarity. In the companion paper (A. M. Rajnicek and C. D. McCaig (1997) J. Cell Sci. 110, 2915-2924) we explore the cellular mechanism for contact guidance of growth cones. PMID- 9359874 TI - Guidance of CNS growth cones by substratum grooves and ridges: effects of inhibitors of the cytoskeleton, calcium channels and signal transduction pathways. AB - We exploited our observation that embryonic Xenopus spinal neurites align parallel to grooves in a quartz surface and that embryonic rat hippocampal neurites align perpendicular to shallow, narrow grooves (see companion paper: A. M. Rajnicek, S. Britland and C. D. McCaig, 1997) (J. Cell Sci. 110, 2905-2913) to investigate the mechanism of growth cone contact guidance. Substratum topography affected the pattern of growth cone filopodia and microtubules but parallel orientation of Xenopus neurites and perpendicular orientation of hippocampal neurites were unperturbed by cytochalasin B, which virtually eliminated filopodia. Hippocampal growth cone orientation and turning in response to grooves was unaffected by disruption of microtubules using taxol or nocodazole. Gross cytoskeletal reorganization on grooved substrata was therefore not required for growth cone steering. Inhibitors were used to identify the signal transduction pathway for perpendicular alignment of hippocampal neurites. Alignment persisted in the presence of gadolinium chloride, a blocker of stretch-activated calcium channels, the G protein inhibitor pertussis toxin, the protein tyrosine kinase inhibitor genistein, the protein kinase A and G inhibitor HA1004, the protein kinase A inhibitor KT5720and the protein kinase G inhibitor KT5823. Low concentrations of the protein kinase C inhibitors stauro-sporine, bisindolylmaleimide or H-7 did not affect perpendicular orientation but higher concentrations inhibited it. The calcium channel blockers flunarizine, nifedipine and diltiazem also inhibited perpendicular orientation. Influx of calcium and protein kinase C activity therefore appear to be involved in perpendicular contact guidance. PMID- 9359875 TI - HSF1 granules: a novel stress-induced nuclear compartment of human cells. AB - Heat shock factor 1 (HSF1) is the ubiquitous stress-responsive transcriptional activator which is essential for the inducible transcription of genes encoding heat shock proteins and molecular chaperones. HSF1 localizes within the nucleus of cells exposed to heat shock, heavy metals, and amino acid analogues, to form large, irregularly shaped, brightly staining granules which are not detected during attenuation of the heat shock response or when cells are returned to their normal growth conditions. The kinetics of detection of HSF1 granules parallels the transient induction of heat shock gene transcription. HSF1 granules are also detected using an HSF1-Flag epitope tagged protein or a chimeric HSF1-green fluorescent protein which reveals that these nuclear structures are stress induced and can be detected in living cells. The spatial organization of HSF1 granules in nuclei of stressed cells reveals that they are novel nuclear structures which are stress-dependent and provides evidence that the nucleus undergoes dynamic reorganization in response to stress. PMID- 9359876 TI - Cell membrane lipid composition and distribution: implications for cell function and lessons learned from photoreceptors and platelets. AB - Photoreceptor rod cells and blood platelets are remarkably different, yet both illustrate a similar phenomenon. Both are strongly affected by membrane cholesterol, and the distribution of cholesterol in the membranes of both cell types is determined by the lipid composition within the membranes. In rod cells, cholesterol strongly inhibits rhodopsin activity. The relatively higher level of cholesterol in the plasma membrane serves to inhibit, and thereby conserve, the activity of rhodopsin, which becomes fully active in the low-cholesterol environment of the disk membranes of these same cells. This physiologically important partitioning of cholesterol between disk membranes and plasma membranes occurs because the disk membranes are enriched with phosphatidylethanolamine, thus providing a thermodynamically unfavorable environment for the sterol. Cholesterol enrichment of platelets renders these cells more responsive to stimuli of aggregation. Stimuli for platelet aggregation cause a rapid transbilayer movement of cholesterol from the outer monolayer. This stimulus dependent redistribution of cholesterol appears to result from the concomitant movement of phosphatidylethanolamine into the outer monolayer. The attractive, yet still unproven, hypothesis is that cholesterol translocation plays an important role in the overall platelet response and is intimately related to the sensitizing actions of cholesterol on these cells. PMID- 9359877 TI - HSF1 transcription factor concentrates in nuclear foci during heat shock: relationship with transcription sites. AB - In this paper, we show that upon heat shock, HSF1 concentrates in the nucleus of diploid human fibroblasts in two large foci. The relative distribution of HSF1 nuclear foci and active heat shock protein (hsp) genes was investigated by combining fluorescence in situ hybridization (FISH) for the detection of hsp nuclear transcripts and immunofluorescence for the detection of HSF1. We show that the HSF1 foci are distinct from the sites of hsp70 and hsp90 genes transcription. This is the second report of ploidy-dependent foci of transcription factors that are independent of their specific transcription sites. However, the correlation between the number of HSF1 foci and the ploidy of the cells strongly supports the existence of a specific chromosomal target for HSF1 foci. PMID- 9359878 TI - Allatostatin decreases stomatogastric neuromuscular transmission in the crab Cancer borealis. AB - The effects of insect allatostatins (ASTs) 1-4 were studied on the stomach musculature of the crab Cancer borealis. Of these, Diploptera-allatostatin 3 (D AST-3) was the most effective. D-AST-3 (10(-6 )mol l-1) reduced the amplitude of nerve-evoked contractions, excitatory junctional potentials and excitatory junctional currents at both cholinergic and glutamatergic neuromuscular junctions. Muscle fiber responses to ionophoretic applications of both acetylcholine and glutamate were reduced by the peptide, but D-AST-3 produced no apparent change in the input resistance of the muscle fiber. D-AST-3 reduced the amplitude of muscle contractures evoked by both acetylcholine and glutamate, but had no effect on contractures induced by a high [K+]. These data suggest that D AST-3 decreases the postsynaptic actions of both neurally released acetylcholine and glutamate. Because an AST-like peptide is found in peripheral sensory neurons that innervate stomatogastric muscles and in the pericardial organs, we suggest that an AST-like peptide may play a role in controlling the gain of the excitatory neuromuscular junctions in the stomach. PMID- 9359879 TI - In situ inhibition of vesicle transport and protein processing in the dominant negative Rab1 mutant of Drosophila. AB - Rab proteins play an essential role in vesicle transport. In particular, RAB1 is thought to participate in the transport of most membrane and secretory proteins. To investigate the role of RAB1 in developing or functioning cells in situ, we constructed transgenic, dominant-negative Rab1 mutants of Drosophila, and examined the protein transport and cellular and subcellular structures of mutant photoreceptor cells. In the transgenic fly, the expression of mutant RAB1 was induced by Gal4 protein, whose expression was triggered by heat treatment (37 degrees C) of the fly. Within several hours after the heat induction, the lumens of the rough endoplasmic reticulum (rER) became swollen, and Golgi bodies were disassembled into vesicle clusters. Corresponding to these changes in cell structure, rhodopsin transport was blocked between the rER and the Golgi body, as indicated by the accumulation of immature rhodopsin carrying a large high-mannose type oligosaccharide chain. Long-term expression of mutant RAB1 caused the degradation of photoreceptive microvilli and the accumulation of numerous swollen rERs, whereas no distinct changes were found in the axonal regions. These results indicate that, in Drosophila photoreceptor cells, RAB1 contributes to the maintenance of local cell structure by mediating vesicle transport between the rER and Golgi body. PMID- 9359880 TI - Pharmacology of skeletal muscle GABA-gated chloride channels in the cockroach Periplaneta americana. AB - The pharmacology of -aminobutyric acid (GABA)-gated chloride channels of the coxal levator (182c,d) muscle of the cockroach Periplaneta americana has been investigated and the data compared with similar findings for the cell body of the cockroach fast coxal depressor motor neurone (Df). Muscle GABA receptors resembled those of the motor neurone cell body in their sensitivity to picrotoxinin and insensitivity to bicuculline. However, muscle GABA receptors were insensitive to the neuronal GABA receptor agonists isoguvacine (10(-4) mol l 1) and 3-aminopropane sulphonic acid (10(-3 )mol l-1). The benzodiazepine flunitrazepam, which at 10(-6 )mol l-1 greatly enhances the amplitude of the motor neurone GABA-induced responses, failed to affect muscle responses to GABA when tested at the same and at a higher (10(-4 )mol l-1) concentration. The convulsant t-butylbicyclophosphorothionate was a weak antagonist of cockroach muscle GABA receptors, whereas several cyclodienes were much more effective antagonists. Thus, studies using a benzodiazepine and several convulsant antagonists reveal differences in the pharmacology of muscle and neuronal GABA receptors of the cockroach Periplaneta americana. PMID- 9359881 TI - A heterotrimeric G protein-phospholipase A2 signaling cascade is involved in the regulation of peroxisomal motility in CHO cells. AB - Peroxisomal motility was studied in vivo in CHO cells following transfection with a green fluorescent protein construct containing the C-terminal peroxisomal targeting signal 1 (GFP-PTS1). Time-lapse imaging and evaluation of difference images revealed that peroxisomes attach to microtubules in a Ca2+ requiring step and are transported in an ATP-dependent manner. Following microinjection of guanosine-5'-O-(3-thiotri-phosphate) (GTP(gamma)S), peroxisomal movements were arrested, indicating regulation by GTP-binding proteins. The effect of GTP(gamma)S was mimicked by AlF4- and mastoparan, two drugs which are known to activate heterotrimeric G proteins. Pertussis toxin which prevents Gi/Go protein activation completely abolished the effect of GTP(gamma)S and mastoparan on peroxisomal motility suggesting that the G protein belongs to the Gi/Go class. At least one effector of the G protein is phospholipase A2 as demonstrated by the observation that the phospholipase A2 activating protein peptide efficiently blocks peroxisomal motility, and that the effect of mastoparan and AlF4- is largely abolished by various phospholipase A2 inhibitors. In summary, these data provide evidence for a new type of regulation of organelle motility mediated by a Gi/Go-phospholipase A2 signaling pathway. This type of regulation has not been observed so far with other cell organelles such as mitochondria, the endoplasmic reticulum or axonal vesicles. Thus, motility is regulated individually for each cell organelle by distinct mechanisms enabling the cell to fulfill its vital functions. PMID- 9359882 TI - Vestibular compensation in lampreys: role of vision at different stages of recovery of equilibrium control. AB - The main motor disorder evoked by unilateral labyrinthectomy (UL) in the lamprey (Lampetra fluviatilis) is a complete loss of equilibrium and rolling (rotation about the longitudinal axis) during swimming. A previous study has shown that the recovery of equilibrium control in the lamprey takes, on average, 33 days. However, lampreys were able to maintain equilibrium if UL was combined with removal of the ipsilateral eye ('surgical compensation' of the vestibular deficit). It was suggested that tonic excitatory inflow, rather than specific information about the orientation of the animal in space delivered by the remaining eye, is important for the recovery of equilibrium control. In the present study, a number of experiments were designed to test this hypothesis. It was found that illumination of the eye contralateral to the UL or continuous electrical stimulation (10 Hz) of the corresponding optic nerve resulted in immediate restoration of equilibrium control. The same result was obtained when the vestibular nerve on the UL side was stimulated. Thus, the roll control system in the lamprey, driven by only one labyrinth, is able to maintain equilibrium provided that the lack of tonic inflow from the missing labyrinth is compensated for by tonic vestibular or visual input. The present study has also shown that the importance of visual input for maintaining equilibrium after UL decreases with time. In animals that achieved a high degree of compensation, removal of the eyes on day 23 after UL evoked decompensation, whereas removal on day 70 did not. A reduction of the significance of visual input was also observed in surgically compensated UL lampreys. In these animals, removal of the remaining eye on days 1 3 after the first surgery resulted in a complete loss of equilibrium, removal on day 7 resulted in a partial loss, whereas removal on days 48-55 did not affect the postural stability. Three lines of evidence suggest that asymmetrical visual input evokes plastic changes in the roll control system. (i) In one group of animals, initially one eye was removed, and then 50 days later the labyrinth ipsilateral to the missing eye and remaining eye were removed. These animals exhibited a mild impairment of equilibrium control, in contrast to the animals in which both surgeries were performed simultaneously. (ii) In another group of animals, initially one eye was removed, and then 50 days later the remaining eye and both labyrinths were removed. These animals exhibited rolling towards the eye that remained intact for longer. (iii) A short-term electrical stimulation (5-10 min daily for 3 days) of the optic nerve (contralateral to UL) in blinded animals considerably improved the equilibrium control compared with that of non stimulated animals; the improvement was observed for 60 days after stimulation. PMID- 9359884 TI - Behavioural analysis of olfactory conditioning in the moth spodoptera littoralis (Boisd.) (Lepidoptera: noctuidae) AB - We studied the associative learning capabilities for behaviourally relevant cues in the moth Spodoptera littoralis. The moths were trained to associate a conditioned stimulus (CS), geraniol odour, with an unconditioned stimulus (US), a sucrose solution. The occurrence of a proboscis extension reflex (PER) was tested. The PER performance during acquisition increased steadily with the number of training trials. Non-associative control procedures did not result in learning. PER conditioning was achieved when the CS was presented 1-3 s before the US. A wide range of inter-trial intervals was able to support conditioning. Males and females learned equally well. Moths could to some degree learn the CS US association after a single trial. These results demonstrate that S. littoralis females and males have a good capability to associate an odour with a reward. The neural basis of olfactory coding in moths has been well studied; thus, the moth provides a powerful system in which to examine the neurobiology of olfactory learning. PMID- 9359883 TI - Localization of cardiac (alpha)-myosin heavy chain mRNA is regulated by its 3' untranslated region via mechanical activity and translational block. AB - We have altered the spontaneous contractile activity of neonatal cardiac myocytes in culture to investigate the re-lationship between mechanical forces, myofibril assembly, and the localization and translation of (alpha)-myosin heavy chain mRNA. Immunofluorescence and in situ hybridization techniques revealed that contracting myocytes display well aligned myofibrils and a diffuse distribution of (alpha)-myosin heavy chain mRNA. Inhibition of contractile activity with the calcium channel blocker verapamil (10 microM) resulted in myofibril disassembly and a perinuclear mRNA distribution within six hours. There was a significant decrease (P<0. 05) of mRNA levels, 5 to 15 micron away from the nucleus following 6 hours of verapamil treatment compared with control cells. Inhibition of protein synthesis with cycloheximide (10 microM) also resulted in perinuclear mRNA localization despite having little effect on contractile activity or myofibril assembly. To determine if the 3' untranslated region of (alpha)-myosin heavy chain mRNA was sufficient for localizing the entire message, a chimeric construct composed of beta-galactosidase coding region followed by (alpha)-myosin heavy chain 3' untranslated region sequences was made as a reporter plasmid and transfected into cultured myocytes. A perinuclear accumulation of ss galactosidase was exhibited in many of the contractile arrested cells (48.3+/ 2.4%, n=7). In contrast, significantly fewer (P<0.05) contracting control (29.1+/ 3.3%, n=7) and strongly contracting, isoproterenol-treated cells (27.2+/-6.1%, n=3) exhibited a perinuclear localization of protein. The distribution of the reporter protein was not affected by the contractile state in cells transfected with a constitutively translated 3'UTR. We propose that mechanical activity of neonatal cardiac myocytes regulates the intracellular localization of alpha myosin heavy chain mRNA via the 3' untranslated region mediated by an initial block in translation. PMID- 9359885 TI - A novel UDP-sugar, UDP-3-ketoglucosamine or UDP-4-ketoglucosamine, from bovine heart muscle reduces metmyoglobin with NAD(P)H. AB - 3-Ketoglucose and similar ketosugars have been identified in microorganisms only and little is known about their functions. UDP-sugars are widely found as an intermediate in sugar metabolism in living organisms. Yet what role UDP-sugars play, or whether they play a direct role in metabolism, is still unknown. UDP sugars were isolated and purified from bovine heart muscle, and a UDP-sugar fraction capable of NAD(P)H-dependent catalytic reduction of metmyoglobin was detected. Subsequent identification revealed that the active UDP-sugar was UDP-3- or UDP-4-ketoglucosamine. These compounds were purified from bovine cardiac muscle by ultrafiltration, anion-exchange column chromatography and reverse-phase chromatography. They were further characterized by determination of their chemical reducing activity, by comparison with synthetic UDP-3- or UDP-4 ketoglucosamine standards using high-performance liquid chromatography, by estimation of molecular mass using fast atom bombardment mass spectrometry, and by Fourier transform infrared microspectroscopy and electron probe microanalysis. The results suggest that UDP-3- or UDP-4-ketoglucosamine reduces metmyoglobin in bovine cardiac muscle. It is important that the reducing activity displayed by this ketosugar is not the effect of UDP-3- or UDP-4-ketoglucosamine alone but depends on NAD(P)H. In other words, this action of UDP-3- or UDP-4 ketoglucosamine is catalytic. PMID- 9359886 TI - 2',3'-Cyclic nucleotide 3'-phosphodiesterase is associated with mitochondria in diverse adrenal cell types. AB - In this study, we have examined the expression and intracellular localisation of the myelin protein 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in bovine adrenal medullary chromaffin cell cultures. By immunoblotting, using two distinct anti-CNP monoclonal antibodies, CNP was detected in medullary cell cultures and expression of CNP was confirmed by reverse transcription and PCR amplification. CNP did not leak from digitonin-permeabilised chromaffin cells, suggesting that there is no cytosolic pool of this protein. Immunofluorescence studies with both antibodies showed that all cells in the medullary chromaffin cell culture were stained with a punctate appearance consistent with an intracellular localisation for CNP. More specifically it was demonstrated that CNP is co-localised with mitochondria. Various cell types in chromaffin cell cultures were stained with a mitochondrial pattern and CNP staining was co-localised with mitochondrial staining. These results show that CNP is a widely expressed protein that is associated with mitochondria and provides new clues as to its cellular function outside of myelin structures. PMID- 9359887 TI - A structure/function analysis of Rat7p/Nup159p, an essential nucleoporin of Saccharomyces cerevisiae. AB - Rat7p/Nup159p is an essential nucleoporin of Sac-charomyces cerevisiae originally isolated in a genetic screen designed to identify yeast temperature-sensitive mutants defective in mRNA export. Here we describe a detailed structural functional analysis of Rat7p/Nup159p. The mutation in the rat7-1 ts allele, isolated in the original genetic screen, was found to be a single base pair change that created a stop codon approximately 100 amino acids upstream of the actual stop codon of this 1,460 amino acid polypeptide, thus eliminating one of the two predicted coiled-coil regions located near the carboxyl terminus of the protein. These coiled-coil regions are essential since an allele lacking both coiled-coil regions was unable to support growth under any conditions. In contrast, no other region of the protein was absolutely required. The SAFG/PSFG repeat region in the central third of the protein was completely dispensable for growth at temperatures between 16 degrees C and 37 degrees C and cells expressing this mutant allele were indistinguishable from wild type. Deletion of the amino terminal third of the protein, upstream from the repeat region, or the portion between the repeat region and the coiled-coils resulted in temperature sensitivity, but the two alleles showed distinct phenotypes with respect to the behavior of nuclear pore complexes (NPCs). Taken together, our data suggest that Rat7p/Nup159p is anchored within the NPC through its coiled-coil region and adjacent sequences. In addition, we postulate that the N-terminal third of Rat7p/Nup159p plays an important role in mRNA export. PMID- 9359888 TI - The contractile properties of the M. supracoracoideus In the pigeon and starling: a case for long-axis rotation of the humerus AB - Wing upstroke in birds capable of powered flight is kinematically the most complicated phase of the wingbeat cycle. The M. supracoracoideus (SC), generally considered to be the primary elevator of the wing, is a muscle with a highly derived but stereotyped morphology in modern flying birds. The contractile portion of the SC arises from a ventral sternum, but its tendon of insertion courses above the glenohumeral joint to insert on the dorsal surface of the humerus. To clarify the role of the SC during wing upstroke, we studied its contractile and mechanical properties in European starlings (Sturnus vulgaris) and pigeons (Columba livia), two birds with contrasting flight styles. We made in situ measurements of isometric forces of humeral elevation and humeral rotation and, in addition, measured the extent of unrestrained humeral excursion during stimulation of the muscle nerve. We also generated passive and active length force curves for the SC of each species. Stimulation of the SC at humeral joint angles of elevation/depression and protraction/retraction coincident with the downstroke-upstroke transition and mid-upstroke produced substantially higher forces of long-axis rotation than elevation. When the humerus was allowed to move (rotate/elevate) during stimulation, we observed rotation about its longitudinal axis of up to 70-80 degrees , but humeral elevations of only 40-60 degrees above the horizontal (as measured in lateral view). In the active length-force experiments, we measured mean (+/-s.d.) maximal tetanic forces of 6.5+/-1.2 N for starlings (N=4) and 39.4+/-6.2 N for pigeons (N=6), unexpectedly high forces approximately 10 times body weight. The working range of the SC in both species corresponds to the ascending limb (but not the plateau) of the active length force curve. The potential for greatest active force is high on the ascending limb at joint angles coincident with the downstroke-upstroke transition, a time when the humerus is depressed below the horizontal and rotated forward maximally. As the SC shortens to counterrotate and elevate the humerus during early upstroke, the potential for active force at shorter lengths declines at a relatively rapid rate. These findings reveal that the primary role of the SC is to impart a high-velocity rotation of the humerus about its longitudinal axis, which rapidly elevates the distal wing. This rapid twisting of the humerus is responsible for positioning the forearm and hand so that their subsequent extension orients the outstretched wing in the parasagittal plane appropriate for the subsequent downstroke. We propose that, at the downstroke-upstroke transition, variable levels of co-contraction of the M. pectoralis and SC interact to provide a level of kinematic control at the shoulder that would not be possible were the two antagonists to work independently. The lack of a morphologically derived SC in Late Jurassic and Early Cretaceous birds precluded a high-velocity recovery stroke which undoubtedly limited powered flight in these forms. Subsequent evolution of the derived SC capable of imparting a large rotational force to the humerus about its longitudinal axis was an important step in the evolution of the wing upstroke and in the ability to supinate (circumflex) the manus in early upstroke, a movement fundamental to reducing air resistance during the recovery stroke. PMID- 9359889 TI - The dynamics of flight-initiating jumps in the common vampire bat Desmodus rotundus. AB - Desmodus rotundus, the common vampire bat (Phyllostomidae: Desmodontinae), exhibits complex and variable terrestrial movements that include flight initiating vertical jumps. This ability is unique among bats and is related to their unusual feeding behavior. As a consequence of this behavior, the wing is expected to have design features that allow both powered flight and the generation of violent jumps. In this study, high-speed cine images were synchronized with ground reaction force recordings to evaluate the dynamics of jumping behavior in D. rotundus and to explore the functional characteristics of a wing operating under competing mechanical constraints. The pectoral limbs are responsible for generating upward thrust during the jump. The hindlimbs stabilize and orient the body over the pectoral limbs. The thumbs (pollices) stabilize the pectoral limb and contribute to extending the time over which vertical force is exerted. Peak vertical force can reach 9.5 times body weight in approximately 30 ms. Mean impulse is 0.0580+/-0.007 N s (mean +/- s.d., N=12), which accelerates the animal to a mean take-off velocity of 2.38+/-0.24 m s-1. A model of the muscular activity during jumping is described that accounts for the characteristic force output shown by these animals during flight-initiating jumps. PMID- 9359890 TI - A dynamic force and moment analysis system for brachiation. AB - We describe a transducer system and analysis strategy that allows the determination of dynamic forces and moments applied by an arm-swinging animal during locomotion. We have employed readily available technology and analysis procedures to produce a low-cost but effective system. The solutions to several problems in the design of the system are provided, and the functional characteristics of the system are demonstrated using both an inert pendulum and an actively brachiating gibbon (Hylobates lar). PMID- 9359891 TI - Spatial variation in epaxial muscle activity during prey strike in largemouth bass (Micropterus salmoides) AB - Epaxial muscle activity during prey strike was measured in two discrete myomeric regions of the largemouth bass Micropterus salmoides to test whether (1) the extreme dorsal region of the epaxial muscle (the epaxial arm region) plays a larger role in prey strike than the region bordering the main horizontal septum (the epaxial cone region), (2) whether the epaxial arm region is more active anteriorly than posteriorly during prey strike and (3) whether the epaxial arm region activity is correlated with the epaxial cone region activity. Electromyographic recordings (EMGs) of four bass were taken from eight different longitudinal, epaxial muscle sites: five sites in the arm region and three sites in the cone region. Selection of electrode sites was based on epaxial muscle dissections in which a set of previously undefined tendons, neurocranial epineural-epaxial connector tendons, were described. Every strike had some activity in the arm region, while 48 % of the total number of prey strikes had zero cone activity. Muscle activity was recorded consistently from the first four anterior electrodes in the arm region of each fish, while the posteriormost arm electrodes showed varying degrees of activity. Muscle intensity recorded from the anterior three epaxial arm electrodes was consistently higher than from the two posterior epaxial arm electrodes, while the onset times and durations of EMGs were variable. Most notably, the arm region of the epaxial muscle is capable of being active without the adjoining cone region, thus demonstrating that activity in the epaxial muscle mass can be spatially regionalized in a manner dependent on behavior. PMID- 9359892 TI - Different excitation-contraction coupling mechanisms exist in squid, cuttlefish and octopod mantle muscle AB - Excitation-contraction (EC) coupling was studied in central zone mantle muscle fibres of a squid (Alloteuthis subulata), a cuttlefish (Sepia officinalis) and an octopod (Eledone cirrhosa). Thin slices of muscle were used for twitch experiments and enzymatic isolation of single fibres for whole-cell patch-clamp studies. The current required for a supramaximal twitch response during direct stimulation of muscle slices was lower for squid than for cuttlefish. In squid, but not in cuttlefish, the current-response relationship was independent of slice thickness (range 0.1-0.5 mm). Twitches of squid and cuttlefish slices were reversibly abolished by removal of extracellular Ca2+. In squid, but not in cuttlefish, the current-response relationship was Na+-dependent, and in the absence of Na+ higher current strengths were required to generate a supramaximal response. In whole-cell voltage-clamp experiments on isolated muscle fibres from squid, cuttlefish and Eledone cirrhosa, a sustained inward current was recorded upon depolarisation. This current was blocked by 5 mmol l-1 Co2+ and suppressed by 10 micromol l-1 nifedipine. In squid, an additional inward fast-activating transient current was seen which was blocked by 2 micromol l-1 tetrodotoxin and depolarised holding potentials. The fast current represents a voltage-activated Na+ channel, and the slow currents represent L-type Ca2+ channels. We conclude that squid possess a specialised rapid EC coupling mechanism in central zone fibres that is absent in cuttlefish and Eledone cirrhosa. PMID- 9359893 TI - L-Glutamate and serotonin are endogenous in squid chromatophore nerves AB - Colour changes in cephalopods are controlled by complex organs termed chromatophores whose radial muscles are directly innervated from the brain. In the squids Alloteuthis subulata and Loligo vulgaris, light microscopy of silver- or Methylene-Blue-stained preparations shows that each muscle is innervated by 2 6 nerves running along its length. An electron microscope (EM) study shows that most of these nerves contain 50 nm diameter electron-lucent vesicles organised into numerous synapses along the muscle. Their size and appearance is consistent with their containing l-glutamate (l-Glu). Usually there is one nerve on each muscle containing 95 nm diameter electron-dense vesicles that are not organised into synapses. Such vesicles, whose appearance is consistent with their containing serotonin (5-HT), are never found co-localised with the small, clear vesicles. Topically applied l-Glu causes the radial muscles to contract (and the chromatophore to expand), even after chronic denervation; this effect is blocked by the glutamate antagonists CNQX and DNQX. In contrast, topically applied 5-HT (or its agonists 8-OH-DOPAT and -methyl 5-HT) induces relaxation of precontracted muscle. Incubation with antibodies to l-Glu (Lg-A), using peroxidase anti peroxidase/diaminobenzidine visualisation, produces specific staining along the radial muscles like that seen with silver. Antibodies to 5-HT produce similar specific staining. When sections of skin that had stained positively with Lg-A in the light microscope are examined at the EM level, it is seen that such staining is confined to nerve axons. These results, showing that l-Glu and 5-HT are endogenous in the nerves innervating squid chromatophores and that the radial muscles contain receptors for both substances, suggest that l-Glu is an excitatory transmitter at squid chromatophore muscles. The way in which 5-HT acts to relax the muscles, however, remains to be established. PMID- 9359894 TI - Amiloride analog stimulation of short-circuit current in larval frog skin epithelium. AB - The skin of the bullfrog Rana catesbeiana tadpole contains an apical non selective cation channel that is activated by amiloride. This is in contrast to the adult skin, which has a highly Na+-selective channel that is blocked by amiloride. The purpose of the present study was to characterize further the nature of the tadpole channel using amiloride and its analogs benzamil, dimethyl amiloride (DMA), 5-(N-ethyl-N-isopropyl)-amiloride (EIPA) and methyl isobutyl amiloride (MIBA). Tadpole skins were mounted in modified Ussing chambers with Ca2+-free KCl or NaCl Ringer on the apical side and standard NaCl Ringer (containing 2 mmol l-1 Ca2+) on the basolateral side. Drugs were added to the apical solution at concentrations between 0.1 and 1000 micromol l-1. Amiloride caused the short-circuit current (Isc) to increase rapidly from near zero to a peak of approximately 30-50 microA and then to decline back towards zero over several seconds. The peak response was largest at 100 micromol l-1. The rate of decline was noticeably faster at the higher concentrations. Benzamil and DMA had similar time courses to amiloride, but with smaller effects on Isc. The largest peak responses occurred at 5-50 micromol l-1. EIPA and MIBA gave small responses at 1-10 micromol l-1 and, at higher concentrations (50-500 micromol l-1), the responses consisted of rapid, small increases in Isc followed by rapid decreases. The largest peak response occurred at 10 micromol l-1 for both drugs. After apical membrane resistance had been reduced by nystatin, addition of analogs to the apical solution caused no change in Isc or transepithelial resistance. This suggests that the decline in Isc after amiloride analog treatment was not due to increases in the resistance of the basolateral membrane. N-(6-Aminohexyl)-5 chloro-1-naphthalenesulfonamide hydrochloride (W-7) blocked stimulation by all of the analogs. These data are consistent with amiloride analogs acting as both activators and inhibitors of short-circuit current in tadpole skin and extend the list of ligands that activate these channels. PMID- 9359895 TI - Localization and release of 5-hydroxytryptamine in the crayfish eyestalk AB - The content and regional distribution of 5-hydroxytryptamine (5-HT) in the crayfish eyestalk was determined by high-performance liquid chromatography. Levels of the 5-HT precursors l-tryptophan (L-TRP) and 5-hydroxytryptophan (5-OH TRP), and of three metabolites, 5-hydroxytryptophol (5-HTPH), N-acetylserotonin (NA-5-HT) and 5-hydroxy-indole-3-acetic acid (5-HIAA), were also determined. The total content of 5-HT in the eyestalk was 95.4+/-49.3 pg mg-1 wet mass (mean +/- s.d., N=55) while the specific content was 9.6+/-4.9 fmol microg-1 protein (mean +/- s.d. N=5). 5-HT was present in all four ganglia of the eyestalk. The highest proportion was found in the medulla terminalis (40.2 %) and the lowest in the retina lamina ganglionaris (9.9 %), which also had the lowest specific content. Conversely, the highest specific content of L-TRP was in the retina lamina ganglionaris. 5-HT biosynthesis and metabolism were explored in isolated eyestalks. The monoamine oxidase blocker pargyline, at concentrations between 0.8 and 10 mmol l-1, elicited a dose-dependent increase in 5-HT content. The biosynthesis of 5-HT in the crayfish eyestalk is suggested by the presence of its immediate precursor (5-OH-TRP) and by the suppression of 5-HT synthesis induced by m-hydroxybenzyl-hydrazine (m-HBH), a blocker of 5-OH-TRP decarboxylase. The presence of immunopositive cell bodies and axons was demonstrated using an anti-5 HT antiserum. 5-HT-like immunopositivity was detected in various regions of the eyestalk. Efferent immunopositive axons were also identified in the optic nerve, and these may have originated in the protocerebral lobe of the supraoesophageal ganglion. The branchings of these axons were profusely distributed in the neuropile of the medulla terminalis. A basal level release of 5-HT was detected in isolated eyestalks. The amount recovered was increased two-to threefold after blocking 5-HT uptake with fluoxetine (1 micromol l-1). Incubation of eyestalks in solutions containing a high K+ concentration (80 mmol l-1) released 5-HT. Electrical stimulation of the optic nerve released 5-HT as a function of the intensity of stimulation. Both the basal and evoked release were suppressed by lowering the Ca2+ concentration in the medium. These observations support a role for 5-HT as a neurotransmitter or neuromodulator in the crayfish eyestalk. PMID- 9359896 TI - Modulation of electrical activity by 5-hydroxytryptamine in crayfish neurosecretory cells. AB - The effect of 5-hydroxytryptamine (5-HT) was tested in a population of X organ neurosecretory cells in the eyestalk of the crayfish Procambarus clarkii. Tests were conducted both in situ and on isolated neurones kept in culture. The application of 5-HT induced action potentials in silent cells. In spontaneously active neurones, 5-HT increased the firing rate and either induced firing or enhanced bursting activity. The effect of 5-HT was dose-dependent within the range 1-100 micromol l-1 in cells of the intact organ. The effect persisted for 20-30 min after 5-HT had been removed from the bathing solution. Successive applications of 5-HT onto the same neurone reduced responsiveness, suggesting that desensitization had occurred. The effects of 5-HT were blocked by prior incubation with the 5-HT antagonist methysergide. In X organ cells whose axons and branches in the neuropile had been severed, 5-HT induced a depolarisation associated with a slow inward current. In X organ neurones isolated from the eyestalk and kept in culture, 5-HT was capable of evoking bursts of action potentials and elicited a slow inward current. This effect was also blocked by methysergide (10(-4 )mol l-1). These results suggest a direct modulatory effect of 5-HT on the pattern of electrical activity in the X organ cells. PMID- 9359897 TI - Involvement of P2-purinergic receptors in intracellular Ca2+ responses and the contraction of mammary myoepithelial cells. AB - Mammary myoepithelial cells were isolated and cultured to characterize their properties. The intracellular calcium concentration (Cai2+) was measured using the ratio of fura-2 fluorescence at 340 nm to that at 360 nm (F340/F360), and the contraction was simultaneously monitored by the change of fluorescence intensity at 360 nm (F360). Cultured myoepithelial cells retained their contractile machinery as in the intact tissue. NBD-phallacidin fluorescence, which marks F actin, and electron microscopy showed abundant bundles of microfilaments in the cytoplasm. Oxytocin (> 0.1 nM) induced an increase in Cai2+ and contraction. The amplitude and time course of the Cai2+ increase were not markedly affected in the Ca2+-free solution. Nifedipine (10 microM) did not affect the response to oxytocin. ATP (>1 microM) induced an increase in Cai2+ and contraction. The response to ATP was not affected by Ca2+ removal, but was suppressed by suramin (100 microM), an antagonist of P2-purinergic receptors. The order of potency of nucleotides to increase Cai2+ was ATP = ADP > UTP > UDP. These findings indicate the presence of P2-purinergic receptors in mammary myoepithelial cells. The results suggest that stimulant-induced Cai2+ increases and contractions are due to release of Ca2+ from intracellular stores in these cells. In addition to the hormonal action of oxytocin, extracellular nucleotides may function as paracrine agents to contract myoepithelial cells in the mammary gland. PMID- 9359898 TI - Volume-sensitive chloride current activated by hyposmotic swelling in antral gastric myocytes of the guinea-pig. AB - The characteristics of volume-sensitive chloride current (ICl) induced by osmotic cell swelling were studied using the whole-cell patch-clamp technique and cell diameters of antral circular guinea-pig myocytes were simultaneously measured under isosmotic and hyposmotic conditions by using a video image analysis system. At -60 mV, osmotic cell swelling (200 mosmol/l) activated a sustained inward current. Instantaneous current/voltage (I-V) relations obtained by step voltage pulses showed an outward rectification. At potentials above +40 mV, the current exhibited time-dependent decay. The outward current amplitude was decreased and the reversal potential was shifted to more positive potentials by replacement of external Cl- with gluconate-, while the current amplitude and the I/V relation were not affected by replacing extracellular Na+ with N-methyl-D-glucamine. The anion permeability sequence of the swelling-induced current was I- (1.80) > Br- (1.31) > Cl- (1) > F- (0.85) > gluconate- (0.18). The ICl was effectively inhibited by the Cl- channel blockers, 4,4'-diisothiocyanatostilbene-2,2' disulphonic acid (DIDS, 100 microM), and niflumic acid (10 microM). DIDS suppressed outward current more effectively than inward current. Also, the ICl was dose-dependently inhibited by arachidonic acid, an unsaturated fatty acid and also inhibited by other unsaturated fatty acids (linoleic acid and oleic acid) but not by stearic acid, a saturated fatty acid. The inhibitory effect of arachidonic acid on ICl was not prevented by indomethacin, a cyclo-oxygenase inhibitor and chelerythrine, a protein kinase C inhibitor. Under whole-cell patch clamp conditions, the cell diameter was continuously measured using video image analysis, which reflects the change in cell volume. A hyposmotic-stimulation induced increase of cell diameter was followed by ICl activation. In intact single gastric myocytes, relatively severe hyposmotic (176 mosmol/l) superfusing solution increased the cell diameter and the pretreatment with DIDS or with niflumic acid significantly potentiated the above effect of hyposmotic superfusion. These results suggest that volume-sensitive outwardly rectifying chloride current (ICl) is present in guinea-pig gastric myocyte and the ICl may play a role in smooth muscle cell volume regulation. PMID- 9359899 TI - Cl- secretion induced by 5-hydroxytryptamine and calcitonin gene-related peptide in rat tracheal epithelia. AB - The effects of 5-hydroxytryptamine (5-HT) and calcitonin gene-related peptide (CGRP), which are colocalized in nerve terminals in the airway, on Cl- secretion in rat tracheal epithelia were tested. Short-circuit current (Isc) was measured after rat tracheal epithelial monolayers were cultured on porous filters. In rat tracheal monolayers 5-HT and CGRP increased Isc upon addition to the serosal compartment, in a dose-dependent manner with EC50 values at 5 micromol/l and 5 nmol/l, respectively. The responses were dependent on the presence of Cl- in the bathing solution and were inhibited by 100 micromol/l bumetanide. When 5-HT or CGRP was added after the administration of forskolin, the responses were not observed. 5-HT and CGRP increased the intracellular cAMP concentration. Low-Ca2+ buffer (0.1 mmol/l) and pretreatment with BAPTA/AM (10 micromol/l), thapsigargin (1 micromol/l) or indomethacin (10 micromol/l) did not affect the responses to 5 HT and CGRP. The 5-HT-induced response was not inhibited by 5-HT2 and/or 5-HT4 antagonists. These results indicate that in the rat tracheal epithelia 5-HT and CGRP increase Cl- secretion by an increase in intracellular cAMP concentration via direct activation of basolateral receptors, and that the response to 5-HT is not mediated via 5-HT4 receptors. PMID- 9359900 TI - Ca2+ and Ba2+ effects on basolateral tetraethylammonium transport in isolated snake renal proximal tubules. AB - Previous work on snake renal tubules suggested that basolateral transport of tetraethylammonium (TEA) is symmetrical. To examine regulation of this transport step more closely, we determined the effects of (1) reductions in the extracellular Ca2+ concentration and basolateral Ca2+ entry, and (2) the presence of extracellular Ba2+ on TEA uptake and efflux across the basolateral membrane of isolated snake renal proximal tubules. Removal of extracellular Ca2+ reduced initial TEA uptake and enhanced TEA efflux. Blocking Ca2+ entry also reduced initial TEA uptake. Extracellular Ba2+ depolarized the basolateral membrane and reduced both TEA uptake and efflux. Inhibition of basolateral TEA uptake with a reduced membrane potential supports previous data indicating that uptake involves potential-driven facilitated diffusion. Inhibition of basolateral TEA efflux by Ba2+ even with a reduced membrane potential not only supports previously obtained data indicating that efflux is not influenced by the potential difference and that basolateral TEA transport is asymmetrical, but also suggests that TEA uptake and efflux may occur by separate pathways. PMID- 9359901 TI - Ca2+-channel-dependent and -independent inhibition of exocytosis by extracellular ATP in voltage-clamped rat adrenal chromaffin cells. AB - Membrane currents and capacitance were measured to examine the effects of extracellular ATP on exocytosis in voltage-clamped rat adrenal chromaffin cells. ATP reversibly inhibited Ca2+ current (ICa) and exocytosis. The dependency of exocytosis on ICa evoked by 1-s depolarizations was determined. However, inhibition of exocytosis was 2.6 times larger than that estimated from the reduction of ICa, implying the existence of a Ca2+-channel-independent pathway. This inhibition did not rely on a further reduction of the intracellular Ca2+ concentration spike. ATP reduced the rate of exocytosis induced by clamping the intracellular Ca2+ concentration. Pertussis toxin blocked the inhibitory effects of ATP on ICa and exocytosis. Although RB-2, a P2Y antagonist, blocked the inhibitory effect of ATP on ICa, RB-2 itself produced large increase or decrease in membrane capacitance. Adenosine inhibited ICa via a pertussis-toxin-sensitive pathway but did not significantly inhibit exocytosis. Our data show that extracellular ATP inhibits exocytosis via inhibition of ICa by activation of a pertussis-toxin-sensitive G-protein linked to P2Y receptors. Furthermore, our data strongly suggest that ATP activates another pathway, which is also G-protein dependent and accounts for the majority of the inhibitory effect of ATP on exocytosis. PMID- 9359902 TI - Modification of rat brain Kv1.4 channel gating by association with accessory Kvbeta1.1 and beta2.1 subunits. AB - We have examined the effects of co-expression of Kvbeta1.1 and Kvbeta2.1 subunits on the gating of rat brain Kv1.4 channels, expressed in Xenopus oocytes. Expression of Kv1.4 subunits alone produced a rapidly inactivating "A" type current, which activated at potentials beyond -60 mV in a solution containing high levels of rubidium. Current activation curves obtained from tail current measurements were fitted with a Boltzmann function, with V1/2 = -47 mV and k = 10 mV. Neither the Kvbeta1.1 nor Kvbeta2.1 subunits altered the voltage dependence of activation. Both subunits accelerated the activation time constant of Kv1.4, without affecting its voltage dependence. Surprisingly, the Kvbeta2.1 subunit, which lacks an N-terminal inactivation domain, was almost as effective as the Kvbeta1.1 subunit in speeding up Kv1.4. Steady-state inactivation of Kv1.4 was unchanged upon co-expression with either Kvbeta1.1 or Kvbeta2.1 subunits. Kv1.4 recovered from inactivation with two time constants; apart from an approximately 50% lengthening of the slow time constant with a high Kvbeta2.1 injection ratio, neither time constant was altered by either the Kvbeta1.1 or Kvbeta2.1 subunits, suggesting little interaction with recovery from C-type inactivation. Clearly, beta subunits have the potential to modify the gating of Kv1.4 channels in the brain more subtly than has been suggested previously. PMID- 9359903 TI - Analogies and differences between omega-conotoxins MVIIC and MVIID: binding sites and functions in bovine chromaffin cells. AB - The characteristics of the binding sites for the Conus magus toxins omega conotoxin MVIIC and omega-conotoxin MVIID, as well as their effects on K+-evoked 45Ca2+ entry and whole-cell Ba2+ currents (IBa), and K+-evoked catecholamine secretion have been studied in bovine adrenal chromaffin cells. Binding of [125I] omega-conotoxin GVIA to bovine adrenal medullary membranes was displaced by omega conotoxins GVIA, MVIIC and MVIID with IC50 values of around 0.1, 4 and 100 nM, respectively. The reverse was true for the binding of [125I] omega-conotoxin MVIIC, which was displaced by omega-conotoxins MVIIC, MVIID and GVIA with IC50 values of around 30, 80 and 1.200 nM, respectively. The sites recognized by omega conotoxins MVIIC and MVIID in bovine brain exhibited higher affinities (IC50 values of around 1 nM). Both omega-conotoxin MVIIC and MVIID blocked IBa by 70 80%; the higher the [Ba2+]o of the extracellular solution the lower the blockade induced by omega-conotoxin MVIIC. This was not the case for omega-conotoxin MVIID; high Ba2+ (10 mM) slowed down the development of blockade but the maximum blockade achieved was similar to that obtained in 2 mM Ba2+. A further difference between the two toxins concerns their reversibility; washout of omega-conotoxin MVIIC did not reverse the blockade of IBa while in the case of omega-conotoxin MVIID a partial, quick recovery of current was produced. This component was irreversibly blocked by omega-conotoxin GVIA, suggesting that it is associated with N-type Ca2+ channels. Blockade of K+-evoked 45Ca2+ entry produced results which paralleled those obtained by measuring IBa. Thus, 1 microM of each of omega conotoxin GVIA and MVIIA inhibited Ca2+ uptake by 25%, while 1 microM of each of omega-conotoxin MVIIC and MVIID caused a 70% blockade. K+-evoked catecholamine secretory responses were not reduced by omega-conotoxin GVIA (1 microM). In contrast, at 1 microM both omega-conotoxin MVIIC and MVIID reduced the exocytotic response by 70%. These data strengthen the previously established conclusion that Q-type Ca2+ channels that contribute to the regulation of secretion and are sensitive to omega-conotoxins MVIIC and MVIID are present in bovine chromaffin cells. These channels, however, seem to possess binding sites for omega conotoxins MVIIC and MVIID whose characteristics differ considerably from those described to occur in the brain; they might represent a subset of Q-type Ca2+ channels or an entirely new subtype of voltage-dependent high-threshold Ca2+ channel. PMID- 9359904 TI - Intracellular alkalinization causes Mg2+ release from intracellular binding sites in leech Retzius neurones. AB - Four-barrelled ion-sensitive microelectrodes were developed to enable simultaneous measurement of intracellular free Mg2+ and Na+ concentrations ([Mg2+]i, [Na+]i), intracellular pH and the membrane potential. The electrodes were used to investigate pH-induced [Mg2+]i changes in Retzius neurones of the leech Hirudo medicinalis. The application of propionate or CO2/HCO3--buffered bath solutions caused a transient intracellular acidification, an initial [Mg2+]i decrease and a continuous [Na+]i increase. In the presence of CO2/HCO3- this [Na+]i increase was more pronounced and might be the reason for the slow increase in [Mg2+]i following the initial decrease. The withdrawal of propionate or CO2/HCO3--buffered bath solutions caused a transient alkalinization which was accompanied by a slight but significant [Mg2+]i increase, even in the nominal absence of extracellular Mg2+, while [Na+]i returned to its original value. The alkalinization-induced [Mg2+]i increase could be reduced to about 50% by the application of 1-10 microM cyclosporin A, an inhibitor of the mitochondrial permeability transition pore (MTP). Phenylarsine oxide, an MTP activator, caused a [Mg2+]i increase with characteristics similar to those of the alkalinization induced increase, which could not be attributed to any changes in [Na+]i or pHi. It is concluded that an intracellular alkalinization might induce the release of Mg2+ from intracellular stores. PMID- 9359906 TI - Heterogeneity of hair cells in the bullfrog sacculus. AB - Morphometric and electrophysiological features of hair cells in the sacculus of the bullfrog (Rana catesbeiana) were studied. Confocal microscopy observations of hair cells in situ revealed that three classes of hair cells can be distinguished by their somata shape and macular location. Two of these, termed central cylindrical (CCHCs) and central flask-shaped (CFHCs) hair cells, were found in the central part of the macula. The third class, termed peripheral elongated hair cells (PEHC), was only found around the perimeter of the sacculus. Using the whole-cell patch-clamp technique CCHCs and CFHCs were distinguished by the amplitude of their voltage-activated calcium currents (ICa). The mean amplitudes of steady-state ICa at -20 mV were -900 +/- 500 pA (n = 18) for CCHCs and -160 +/ 70 pA (n = 10) for CFHCs. The two hair-cell types also differed in the possession of a Cs+-resistant, apamin-sensitive, calcium-sensitive potassium current, found only the CFHCs. This study indicates that several populations of hair cells with distinct morphological features exist in the bullfrog sacculus, and that at least two of these differ in their complement of membrane conductances. PMID- 9359905 TI - Role of anions in the regulation of cell volume and intracellular pH in perfused rat mandibular salivary gland. AB - To investigate the role of Cl- in the regulation of the basolateral transporters of salivary acinar cells, we have measured cell volume and intracellular pH (pHi) in perfused rat mandibular glands using proton NMR spectroscopy and BCECF fluorometry respectively. When perfusate Cl- was replaced by glucuronate, isethionate, methylsulphate, nitrate or thiocyanate, cell volume decreased slowly by about 15% over a 10-min period. Replacement with bromide, which substitutes for Cl- on the Na+-K+-2Cl- cotransporter, caused only a small (4%) reduction in cell volume. Replacement of Cl- by glucuronate, isethionate or methylsulphate evoked a biphasic increase in pHi consisting of a rapid initial increase followed by a slower secondary rise whose time course was similar to that of cell shrinkage. As judged by the effects of HCO3- omission, 100 microM 4,4' diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) and 1 mM amiloride, the initial rise in pHi was due to Cl-/HCO3- exchange while the secondary rise resulted from activation of Na+/H+ exchange. Although replacement of Cl- by nitrate or thiocyanate also caused cell shrinkage, these substituting anions were less effective in activating the exchanger. Therefore, while the upregulation of the exchanger following Cl- replacement may be due in part to cell shrinkage, there is also evidence for the involvement of an anion-sensitive regulatory mechanism. This would be consistent with the hypothesis that both changes in cell volume and in intracellular Cl- concentration contribute to the up-regulation of the exchanger following muscarinic stimulation. PMID- 9359907 TI - The action of perchlorate on malignant-hyperthermia-susceptible muscle. AB - To better understand the altered skeletal muscle excitation-contraction (E-C) coupling that occurs in malignant hyperthermia, we have examined the potentiating actions of perchlorate in intact muscle fiber bundles, isolated sarcoplasmic reticulum (SR) vesicles, and the purified ryanodine receptor/Ca2+ release channel (RyR) isolated from malignant-hyperthermia-susceptible (MHS) and normal porcine muscle. The concentration of perchlorate that half-maximally potentiated twitch tension (2.5-3.5 mM) was not significantly different for MHS and normal muscles. The effect of perchlorate on fractional twitch force was significantly greater for normal than for MHS muscle, although the absolute twitch potentiation was similar for both muscle types. The K-contracture threshold of MHS muscle bundles is significantly lower than that of normal bundles; perchlorate shifted the K contraction activation curves of both MHS and normal muscle bundles to lower K+ concentrations. Perchlorate both increased ryanodine binding to MHS and normal SR vesicles and increased single-channel open probability of the purified MHS and normal RyR. In both cases, the percentage increase was greater for normal than for MHS preparations; however, the absolute increase in activity was not different for MHS and normal RyR indicating that there is no difference in the perchlorate sensitivity of MHS and normal SR Ca2+ release channels. Thus, the greater absolute responses of the MHS Ca2+ release channel in the presence of perchlorate is likely to be due to the greater basal activity of the MHS release channel and does not reflect an underlying defect in the site of action of perchlorate on the MHS skeletal muscle Ca2+ release channel. PMID- 9359908 TI - Action of the hyperpolarization-activated current (Ih) blocker ZD 7288 in hippocampal CA1 neurons. AB - The effects of ZD 7288, a "bradycardic" agent, in young rat hippocampal slices in vitro were studied. ZD 7288 (1-1000 microM) reduced the hyperpolarization activated current (Ih) in CA1 pyramidal neurons by a voltage-independent blocking mechanism. Under current-clamp conditions, the bradycardic agent (10 microM) caused membrane hyperpolarization (by 5.9 +/- 0.5 mV) and a reduction of membrane conductance (by 17.9 +/- 4.1%). These data are consistent with the block of an inward current which is active at rest. The drug-induced hyperpolarization depressed the cell's excitability by increasing the threshold current necessary to induce firing. When the drug-induced hyperpolarization was compensated for by injection of a tonic depolarizing current, ZD 7288 caused a reduction of the inhibitory post-synaptic potential (IPSP) in EPSP-IPSP sequences. Since Cs+, another known blocker of Ih, is able to reverse long-term depression (LTD) of the CA3-CA1 synapse in hippocampal slices, we tested the effect of ZD 7288 on synaptic transmission. We found that ZD 7288 did not significantly modify LTD, suggesting that Cs+-induced inhibition of LTD maintenance is not directly related to block of Ih. PMID- 9359909 TI - Independent responsiveness of frog liver low-density lipoprotein receptor and HMGCoA reductase to estrogen treatment. AB - Cholesterol metabolism in the female frog exhibits circannual modifications which parallel plasma estrogen fluctuations. Estrogens enhance production and lipidation of the yolk precursor vitellogenin by inducing the transcription of its gene and by stimulating the activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase. The time dependence of the effects that these hormones have on HMGCoA reductase and the low-density lipoprotein (LDL) receptor in the liver of Rana esculenta complex has been investigated. Following estrogen treatment, the levels of LDL receptor mRNA and protein gradually increased, with a maximum concentration observed at 3 days. The HMGCoA reductase protein level increased progressively, while the mRNA level was not significantly modified. Thus the LDL receptor and HMGCoA reductase in frog behave independently after estrogen stimulation, as already reported to occur in the rat. This suggests a uncoordinated regulation that might be even partially related with the changes in cellular cholesterol content. PMID- 9359910 TI - Changes in subsarcolemmal sodium concentration measured by Na-Ca exchanger activity during Na-pump inhibition and beta-adrenergic stimulation in guinea-pig ventricular myocytes. AB - Measurement of Na-Ca exchange activity was used to examine subsarcolemmal sodium levels ([Na+]s) in single, voltage-clamped guinea-pig cardiac myocytes while Na-K pump activity was modulated pharmacologically. Changes in Nas were evaluated from phase-plane analysis of the changes in intracellular calcium, measured using the fluorescent indicators Fura-red and Fluo-3. Activation of beta-adrenoceptors with 1 microM isoprenaline resulted in activation of the cAMP-dependent chloride current, but had no effect on the calcium transient mediated via the Na-Ca exchanger, regardless of whether the Na-K pump was active or inhibited (with strophanthidin). The ability of Na-Ca exchange activity to report [Na+]s was demonstrated by the effect of changing the extracellular rubidium concentration from 1 to 5.4 mM to modulate Na-K pump activity. We suggest that beta-adrenergic stimulation does not directly affect either the Na-K pump or the Na-Ca exchanger and that the Na-Ca exchanger can be used as a sensitive indicator of changes in [Na+]s and Na-K pump activity. PMID- 9359912 TI - The effect of sarcoplasmic reticulum blockade on the force/frequency relationship and systolic contraction patterns in the newborn pig heart. AB - We investigated the relationship between heart rate and contractility in seven anaesthetized young piglets by measuring contractility at different atrial pacing rates. To study the origin of this relationship we repeated the measurements after blocking the sarcoplasmic reticulum calcium release channel with ryanodine. We assessed contractility using indices derived from instantaneous left ventricular pressure and volume measured by micromanometric and conductance catheters during rapid inferior vena cava occlusion, thus generating the end systolic pressure-volume relationship, which was characterized by its slope Ees, and the maximum rate of change of ventricular pressure (dP/dtmax)/end-diastolic volume relationship, also characterized by its slope. All animals showed an increase in contractility with increasing heart rate (intact force/frequency relationship) which was abolished after ryanodine. The most striking effect of ryanodine on baseline haemodynamics was the dramatic decrease of dP/dtmax to about 50% of its original value, while peak developed pressure and Ees did not change. We conclude that the young piglet, despite its immaturity, has a functional sarcoplasmic reticulum, illustrated by an intact force/frequency relationship. In addition, blockade of the sarcoplasmic reticulum in vivo has profoundly different effects during early and late systole, indicating that indices of contractility derived during different parts of the cardiac cycle represent different aspects of systole. PMID- 9359911 TI - Demonstration of an inwardly rectifying K+ current component modulated by thyrotropin-releasing hormone and caffeine in GH3 rat anterior pituitary cells. AB - Reduction of an inwardly rectifying K+ current by thyrotropin-releasing hormone (TRH) and caffeine has been considered to be an important determinant of electrical activity increases in GH3 rat anterior pituitary cells. However, the existence of an inwardly rectifying K+ current component was recently regarded as a misidentification of an M-like outward current, proposed to be the TRH target in pituitary cells, including GH3 cells. In this report, an inwardly rectifying component of K+ current is indeed demonstrated in perforated-patch voltage clamped GH3 cells. The degree of rectification varied from cell to cell, but both TRH and caffeine specifically blocked a fraction of current with strong rectification in the hyperpolarizing direction. Use of ramp pulses to continuously modify the membrane potential demonstrated a prominent blockade even in cells with no current reduction at voltages at which M-currents are active. Depolarization steps to positive voltages at the maximum of the inward current induced a caffeine-sensitive instantaneous outward current followed by a single exponential decay. The magnitude of this current was modified in a biphasic way according to the duration of the previous hyperpolarization step. The kinetic characteristics of the current are compatible with the possibility that removal from inactivation of a fast-inactivating delayed rectifier causes the hyperpolarization-induced current. Furthermore, the inwardly rectifying current was blocked by astemizole, a potent and selective inhibitor of human ether-a-go go -related gene (HERG) K+ channels. Along with other pharmacological and kinetic evidence, this indicates that the secretagogue-regulated current is probably mediated by a HERG-like K+ channel. Addition of astemizole to current-clamped cells induced clear increases in the frequency of action potential production. Thus, an inwardly-rectifying K+ current and not an M-like outward current seems to be involved in TRH and caffeine modulation of electrical activity in GH3 cells. PMID- 9359914 TI - Mechanical and energy characteristics during shortening in isolated type-1 muscle fibres from Xenopus laevis studied at maximal and submaximal activation. AB - The mechanical and energy characteristics of isolated fast-twitch muscle fibres (type 1) of Xenopus laevis in isometric- and isovelocity contractions were measured at 20 degrees C. The fibres were stimulated at either 60 Hz or 20 Hz to produce contractions at different levels of activation. The high stimulation frequency gave fused contractions, while at the low stimulation frequency tension fluctuated. When maximum isometric force had been reached, the fibres were shortened by 10% of the fibre length at different velocities. At 60 Hz stimulation during shortening the rate of heat production increased above the isometric rate of heat production. At 20 Hz stimulation during shortening, however, the rate of heat production was not different from the isometric rate of heat production. Mechanical efficiency was the same at the high and low level of activation. The actomyosin efficiency (i.e. the mechanical efficiency corrected for "activation heat") was highest at the low level of activation. We conclude that in fast-twitch muscle fibres from X. laevis, actomyosin efficiency is highest for partially activated muscle. From a comparison of the present results with those obtained from a study of slow-twitch muscle fibres presented earlier, it is concluded that fast-twitch muscle fibres are less efficient than slow twitch muscle fibres. PMID- 9359913 TI - Mast cell-mediated induction of ICAM-1, VCAM-1 and E-selectin in endothelial cells in vitro: constitutive release of inducing mediators but no effect of degranulation. AB - Mast cell (MC)-mediated induction of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and of E-selectin was studied in cultures of rat heart endothelial cells (EC) and human umbilical vein EC (HUVEC) respectively. MC induced VCAM-1 and E-selectin, but hardly any ICAM-1 in EC. Induction was not dependent on MC degranulation, but seemed to be provoked by constitutively released substances, other than histamine, from MC. Co-incubation of MC and EC, allowing for direct contact between the two cell types, was more potent in induction than MC co-incubated separately from EC using a permeable membrane. MC were less potent in induction than exogenous added cytokines or LPS. Induction of cell adhesion molecules in rat heart EC was MC-specific, since EC incubations with either rat cardiomyocytes or heart fibroblasts had no effect. The data show that rat MC, independent of degranulation, secrete mediators relevant for the induction of a specific set of EC adhesion molecules in vitro. This suggests a (supportive) role for MC in cell-adhesion molecule induction in the endothelium in settings of early or mild inflammation. The results are discussed in the context of inflammatory processes in the heart in vivo. PMID- 9359915 TI - Comparison of the molecular, antigenic and ATPase determinants of fast myosin heavy chains in rat and human: a single-fibre study. AB - Combined methodologies of histochemistry, immunohistochemistry, sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), reverse transcriptase polymerase chain reaction (RT-PCR) and a histochemical method specific for myofibrillar ATPase (mATPase) of the type IIX myosin heavy chain (MyHC) isoform were used to study human and rat single fibres to examine the homology between type II MyHC isoform-based fibres of both species. We demonstrate that human type II fibres exhibit antigenic mATPase and 3'-untranslated region (3'-UTR) sequence determinants homologous to the IIA and IIX but not the IIB MyHC isoforms of the rat. Both immunolabelling with anti-MyHC monoclonal antibodies and the mATPase method used with frozen sections confirmed that all human type II fibres express type IIA and/or type IIX MyHC. Quantitative immunohistochemistry failed to recognize human fibres with antigenic characteristics corresponding to hybrid IIXB MyHC-based fibres. Ca2+-stimulated maximum myosin ATPase activity, determined by quantitative histochemistry, revealed that human IIX fibres (with an optical density or OD = 0.707) display enzyme activity which is comparable to that of the rat type IIX (OD = 0.687) but lower than that of the rat type IIB fibres (OD = 0.836). The results do not support the notion that MyHC IIB is expressed in human limb muscles, even in hybrid fibres. We conclude that human type II fibres have been misclassified in numerous previous publications and that this has important implications in attempts to compare the physiological characteristics of fibre types, particularly when animal models are used. PMID- 9359916 TI - "Voltage-activated Ca release" in rabbit, rat and guinea-pig cardiac myocytes, and modulation by internal cAMP. AB - It is widely believed that Ca release from the sarcoplasmic reticulum (SR) in heart muscle is due to "Ca-induced Ca-release" (CICR), triggered by transmembrane Ca entry. However, in intact guinea-pig cells or cells dialysed with cAMP there may be an additional mechanism - SR release may be activated directly by membrane depolarisation without Ca entry. The first objective of the present study was to investigate whether this "voltage-activated Ca release" (VACR) mechanism is present across species such as rabbit, rat and guinea-pig. The second objective was to characterise the dependence of a VACR mechanism on internal [cAMP]. Membrane current was measured with the whole-cell patch-clamp technique, intracellular [Ca] was monitored with Fura-2 (or a combination of Fluo-3/SNARF 1). Rapid changes of superfusate (within 100 ms) were made using a system which maintained cell temperature at 37 degrees C. We used a train of conditioning pulses to ensure a standard SR load before each test pulse. In rabbit myocytes dialysed with 100 microM cAMP, 89.6 +/- 7.0% of the control intracellular Ca (Cai) transient was still elicited by depolarisation during a switch to 5 mM Ni, which blocked pathways for Ca entry. This suggested that rabbit myocytes possess a VACR mechanism. The percentage of control Cai transient elicited by depolarisation in the presence of 5 mM Ni (i.e. magnitude of VACR) increased in a graded fashion with the pipette [cAMP] between zero and 100 microM. In rat myocytes dialysed with 50 microM cAMP, 64.4 +/- 6.2% of SR release was activated by depolarisation in the presence of 5 mM Ni, suggesting the presence of a VACR mechanism. The extent to which VACR triggered SR release increased with the pipette [cAMP] between zero and 50 microM. In guinea-pig myocytes dialysed with 100 microM cAMP, 74.6 +/- 3.6% of the control Cai transient was elicited by depolarisation in the presence of 5 mM Ni. The degree to which VACR triggered SR release was also graded with the pipette [cAMP] between zero and 100 microM. It therefore appears that each of the three species might possess a VACR mechanism which can be modulated by the internal [cAMP]. This may reflect an effect of cAMP to phosphorylate key proteins involved in excitation-contraction coupling. Under normal physiological conditions with a basal [cAMP] between 2 and 20 microM, VACR may play a role in triggering SR release. The role of VACR may increase under conditions which increase internal [cAMP]. PMID- 9359917 TI - Capillary force-driven cell perfusion microchamber: calcium transients in isolated smooth muscle cells. AB - We present a new design for a sub-microlitre chamber which enables perfusion of individual cells. No equipment is required for it to be operational, as the exchange of solutions in the chamber is driven solely by capillary forces. Its active volume consists of a 30-micron-thin layer between two coverslips (separated by a couple of spacers) and is adjustable down to 0.1 microl. This slimline design (1) guarantees that all cells are kept in one (focal) plane during recording/perfusion (thus minimizing movement artefacts when intracellular fluorescence is monitored); (2) facilitates fixing of cells to a coverslip (often even without the use of poly-L-lysine, especially when small cell clusters are used); and (3) makes it possible to perfuse individual cells on a specimen stage of an upright microscope even under high-power objectives with a short working distance, which is of potential use in field studies where the smaller size of an upright microscope (compared to the inverted one) can be advantageous. As an example, we present a chamber with an active volume of approx. 0.5 microl and perfusion rate high enough to enable complete exchange of solution within 250 ms in an area of 500 micron x 500 micron. Only 1 microl of perfusing solution is required for exchanging the entire volume of the chamber. We present an example of intracellular free calcium transients in isolated smooth muscle cells upon release of intracellular sequestered calcium. PMID- 9359918 TI - The cystic fibrosis transmembrane conductance regulator attenuates the endogenous Ca2+ activated Cl- conductance of Xenopus oocytes. AB - Oocytes from Xenopus laevis activate a Ca2+ dependent Cl- conductance when exposed to the Ca2+ ionophore ionomycin. This Ca2+ activated Cl- conductance (CaCC) is strongly outwardly rectifying and has a halide conductivity ratio (GI- / GCl-) of about 4.4. This is in contrast to the cystic fibrosis transmembrane conductance regulator (CFTR)-Cl- conductance, which produces more linear I/V curves with a GI- / GCl- ratio of about 0.52. Ionomycin enhanced CaCC (DeltaG) in water injected and CFTR expressing ooyctes in the absence of 3-isobutyl-1 methylxanthine (IBMX, 1 mmol/l) by (microS) 23 +/- 1.9 (n=9) and 23.6 +/- 2.3 (n=11). Stimulation by IBMX did not change CaCC in water injected oocytes. CaCC was inhibited in CFTR-expressing ooyctes after stimulation with IBMX or a membrane permeable form of cAMP and was only 5.1 +/- 0.48 microS (n=18) and 6. 9 +/- 0.6 (n=3), respectively. Inhibition of CaCC was correlated to the amount of CFTR-current activated by IBMX. DeltaF508-CFTR which demonstrates only a small residual function in activating a cAMP dependent Cl- channel in oocytes inhibited CaCC to a lesser degree (DeltaG=12.1 +/- 1.1 microS; n=7). Changes of CFTR and CaCC-Cl- whole cell conductances were also measured when extracellular Cl- was replaced by I-. The results confirmed the reduced activation of CaCC in the presence of activated CFTR. No evidence was found for inhibition of CFTR-currents by increase of intracellular Ca2+. Moreover, intracellular cAMP was not changed by ionomycin and stimulation by IBMX did not change the ionomycin induced Ca2+ increase in Xenopus oocytes. Taken together, these results suggest that activation of CFTR-Cl- currents is paralleled by an inhibition of Ca2+ activated Cl- currents in ooyctes of Xenopus laevis. These results provide another example for CFTR-dependent regulation of membrane conductances other than cAMP-dependent Cl- conductance. They might explain previous findings in epithelial tissues of CF knockout mice. PMID- 9359919 TI - Simultaneous measurements of electrical activity, intracellular [Ca2+] and force in intact smooth muscle. AB - Although both electrical activity and changes in intracellular [Ca2+] are known to be important determinants of smooth muscle force, little is known about the relationship between the three in intact muscle. This is due to a lack of simultaneous measurements of these parameters. In this paper we describe how we have combined the sucrose gap technique with microspectrophotometry and force recording in rat ureteric smooth muscle. We have investigated the timecourses of the changes in these parameters following physiological stimulation i.e. the action potential. The results of this paper show that it is possible to simultaneously measure electrical activity, [Ca] and force in intact smooth muscle and that (i) about a third of the change in Ca2+ occurs on the upstroke of the action potential and the remainder during the plateau. (ii) 50% of the decline in [Ca2+] occurs after the repolarization of the action potential and (iii) the kinetics of force development and relaxation are significantly slower than those of Ca2+, suggesting that [Ca2+] is not rate-limiting. These are the first such simultaneous measurements in any smooth muscle. PMID- 9359920 TI - Expression of osteonectin in articular cartilage of osteoarthritic knees. AB - The expression of osteonectin (ON) in osteoarthritic articular cartilage was investigated by enzyme immunohistochemistry and colloidal gold immunoelectron microscopy. A total of 96 specimens from 9 knees of 8 patients with osteoarthritis (OA) were examined. In OA cartilage, ON-positive cells varied in distribution and were not seen in all the specimens obtained from the same patient. However, in over half of the specimens (56 of 96), especially in the specimens on Mankin's grades from 4 to 9, which corresponds to relatively early stages of OA, ON was expressed in the cartilage above the calcified layer. On the other hand, ON was detected only in the calcified layer below the tidemark in normal articular cartilage. In addition, colloidal gold immunoelectron microscopy revealed ON in chondrocytes and matrix vesicles (MVs). These findings suggest that ON acts through MVs in the early stages of OA as a significant pathogenetic factor involved in intracartilage calcification, which is known to have a close relationship to the progression of OA. PMID- 9359921 TI - Geranylgeranylacetone and cetraxate hydrochloride increase UDP galactosyltransferase activity in rat gastric mucosa. AB - UDP-galactosyltransferase (UDP-Gal-T) is a key enzyme in the synthesis of mucus glycoprotein which plays an important role in gastric mucosal defensive mechanisms. Analysis of gastric UDP-Gal-T activity should clarify the mechanisms of the action of antiulcer drugs regarding gastric defensive factors. Here, we examined UDP-Gal-T activity in rat gastric mucosa treated with the antiulcer drugs geranylgeranylacetone (GGA) and cetraxate hydrochloride (CET). The effects of coadministration of indomethacin and exogenous administration of prostaglandins (PGs) were also studied. GGA and CET significantly increased UDP Gal-T activity, and coadministration of indomethacin inhibited the increase of enzyme activity. UDP-Gal-T activity level with GGA was significantly higher than the control level, even in the presence of indomethacin. With CET, however, this was not the case. Among PGs, PGE1 significantly increased enzyme activity. Concomitant administration of PGE1 and GGA or CET increased UDP-Gal-T activity even with indomethacin to the levels achieved when these antiulcer drugs were administered without indomethacin. Our findings suggest that GGA and CET exert antiulcer effects by increasing mucus glycoprotein synthesis and that endogenous PG synthesis may be involved in this process. However, mechanisms not mediated by endogenous PGs may also exist in the stimulatory action of GGA on UDP-Gal-T activity. PMID- 9359922 TI - The effects of growth factors on multicellular spheroids formed by chick embryonic retinal cells. AB - Retinal cells from chick embryos aged 7.5 days of gestation were cultured for two months in a non-adherent suspension culture dish to study the effects of growth factors and co-culture with retinal pigment epithelial cells on their differentiation. Dissociated retinal cells became cellular aggregates (multicellular spheroids) within a day, and rosettes were formed in the spheroids after 2 days. Ultrastructurally, neurons of the rosettes developed connecting cilia, ellipsoids (accumulation of mitochondria), and external limiting membrane, indicative of their differentiation into photoreceptor cells. Epidermal growth factor enhanced the expression of rhodopsin by rosette-forming neurons, while basic fibroblast growth factor induced the growth of Mueller cells at 4 weeks, and their transdifferentiation into lens-epithelial-like cells at 8 weeks. Co culture of retinal cells with retinal pigment epithelial cells enhanced the formation of rosettes in spheroids. Multicellular spheroids formed in a dish for suspension culture would provide a convenient in vitro system to examine differentiation and transdifferentiation of the retina. PMID- 9359923 TI - Yeast functional assay of the p53 gene status in human cell lines maintained in our laboratory. AB - We used a yeast functional assay (functional analysis of separated alleles in yeast: FASAY) to determine the p53 gene status of human cell lines maintained in our laboratory. This assay enables the researcher to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS 3 via the p53-responsive GAL 1 promoter in Saccharomyces cerevisiae. The cell lines examined were ten hepatoma, two hepatoblastoma, three in vitro immortalized fibroblast, two osteosarcoma, a chondrosarcoma, an ovarian teratocarcinoma and a colon cancer cell line. Out of 20 cell lines, 11 cell lines had mutations in both alleles of the p53 gene, and another 8 cell lines had no mutation in the p53 gene. Thus, 55% of the cell lines examined had mutations in the p53. Interestingly, PA-1 cells had both the normal and the mutant p53 alleles, showing that FASAY is a useful method for detecting the wild-type and mutated p53 genes simultaneously. As for the three liver cell lines harboring HBsAg, there was no relationship between their p53 gene status and the presence of HBsAg. Two cell lines were normal for p53 status, while the other had a mutation of the p53 gene. PMID- 9359924 TI - Muscle strength in rheumatoid elbow: quantitative measurement and comparison to Larsen's X-ray grade. AB - Accurate assessment of elbow function is important to determine the total ability of the arm. The purpose of this study was to clarify the relationship between isometric muscle strength of the elbows of patients with rheumatoid arthritis (RA) and Larsen's X-ray evaluation. Fifty-six elbows of 45 RA patients aged 47 to 77 years (mean age, 63 years) were tested. Muscle strength was measured with an isometric torque-cell dynamometer. Test-retest reliability of the dynamometer was proven by measuring 12 elbows of 6 healthy young men. In RA patients, elbow flexion and extension strength decreased in proportion to increases in the severity of Larsen's grades from Grade 1 to 4. However, Grade 5 elbows had greater muscle strength than those in Grade 4. Forearm pronation and supination strength also decreased in proportion to increases in the severity of Larsen's grades from Grade 1 to 5. This quantitative study made it clear that the muscle strength of RA patients' elbows almost completely correlates to X-ray finding according to the grade of Larsen's evaluation based on X-rays. With regard to muscle strength of postoperative elbows, both flexion strength and supination strength after total elbow replacement (TER) were about two times greater than before TER, and after synovectomy it was as great as those in non-operative RA patients of Grade 2. PMID- 9359925 TI - Use of fluid-attenuated inversion recovery (FLAIR) pulse sequences for differential diagnosis of hepatic hemangiomas and hepatic cysts. AB - Fluid-attenuated inversion recovery (FLAIR) imaging of hepatic hemangiomas (10 patients, 16 lesions) and hepatic cysts (8 patients, 10 lesions) was performed. All hemangiomas were hypointense on T1-weighted images and hyperintense on T2 weighted images. With Gd-DTPA (0.1 mmol/kg), all hemangiomas were enhanced but not all cysts. It was necessary to perform contrast enhanced imaging to differentiate hepatic hemangiomas from hepatic cysts. However, on FLAIR imaging, hepatic hemangiomas were strongly hyperintense and 9 of the 10 hepatic cysts were isointense. One of the hepatic cysts was slightly hyperintense. FLAIR images were useful in differential diagnosis of hepatic hemangiomas and hepatic cysts without using Gd-DTPA. PMID- 9359926 TI - Osteoporosis due to testicular atrophy in male leprosy patients. AB - A study was conducted to examine the relationship of testicular atrophy to bone metabolism in male leprosy patients. The study consisted of 31 leprosy patients (mean age: 62.0 years) and 31 healthy control men (mean age: 60.0 years). Measurements were made of their serum levels of free testosterone (FT), estradiol (E2), luteinizing hormone (LH) and 25-hydroxyvitamin D (25 OHD). Bone mineral density (BMD) was measured at radial sites and the lumbar vertebral bodies (L2 L4) by dual-energy X-ray absorptiometry using a Hologic QDR-2000 densitometer. FT and E2 levels were significantly lower and LH levels higher in leprosy patients than in controls. This represents a primary hypogonadal pattern. A value of 7.20 pg/ml of FT ( = Mean - 1 SD of control) was used as a cut off value, and the subjects were subdivided into a hypogonadal group (HG) and a non hypogonadal group (non-HG). When the subjects were compared for differences in age, age at onset of disease, duration of disease, body mass index and BMD, only the duration of disease and BMD were significantly different between the two groups. Furthermore, BMD of the forearm significantly correlated with FT levels (r = 0.689, P < 0.0001). Low BMD may be due to orchitis and testicular atrophy. PMID- 9359927 TI - Kniest dysplasia: patient's growth progress and development--evolution of abnormalities, 30 year follow up. AB - A case of a male patient with Kniest dysplasia is reported. The patient's growth and the development and evolution of the patient's abnormalities were tracked for a 30 year period, starting at the patient's birth. The clinical and radiographic features during this period, along with the differential diagnosis of Kniest dysplasia, are discussed. Femoral capital epiphyses and the presence of a cataract in one eye were noted from the early stages of the patient's life. The patient's final height was 165 cm. We believe this to be the first long-term follow up of this condition. PMID- 9359928 TI - The cost of adverse drug reactions. PMID- 9359929 TI - Famous names: The Esing Bakery, Hong Kong. PMID- 9359930 TI - Drug-related hyperprolactinaemia. PMID- 9359931 TI - Adverse drug reactions in hospital and in the community. PMID- 9359932 TI - Benztropine abuse and overdose--case report and review. AB - The abuse and overdose of anti-cholinergic agents such as benztropine is well reported in the psychiatric and emergency medicine journals. However, despite almost 40 years since the first modern report, physicians in general remain poorly aware of anti-cholinergic abuse. A case report of recreational overdose of benztropine in a 19 year old schizophrenic patient is presented. Delirium and anti-cholinergic manifestations persisted for five days necessitating prolonged hospitalization. The literature on benztropine abuse and overdose is reviewed. PMID- 9359933 TI - Opinion of the EMEA on the potential risk associated with medicinal products in relation to bovine spongiform encephalopathy (BSE) (16 April 1996) and report from the Committee for Proprietary Medicinal Products (CPMP) on the 'Note for Guidance on minimizing the risk of transmitting animal spongiform encephalopathies via medicinal products' (15 April 1997). PMID- 9359934 TI - Therapeutic management of hematological malignancies in elderly patients. Biological and clinical considerations. Part 1. Myelodysplasias and the acute leukemias. AB - The different therapeutic options that may be employed in the treatment of elderly patients with acute leukemias and myelodysplastic states are considered following an analysis of certain biological features, that have been investigated by cytochemical, cytogenetic and cytokinetic techniques, immunophenotyping, and studies on G-6-PD isoenzymes. These studies imply that in the elderly the pattern of hematological malignancies and the lack of response to conventional treatment derive from intrinsic biological differences between these pathological states in older and younger patients. Treatment in elderly patients has ranged from palliative treatment to intensive chemotherapy, often with disappointing results in both cases. Palliative treatment does not induce remissions, and median survival is short. On the other hand, elderly patients do not tolerate well both induction and post-remission therapy due to the degree of toxicity and the effects of drug-induced pancytopenia. In this scenario, in vitro drug-sensitivity testing and karyotyping assume increasing importance, because they may predict which patients are likely to benefit from intensive therapy. In both acute leukemias and myelodysplasias, treatment ideally should be designed case by case, according to the hematological, clinical and biological features. PMID- 9359935 TI - Role of homocysteine in age-related vascular and non-vascular diseases. AB - Homocysteine (Hcy) may represent a metabolic link in the pathogenesis of atherosclerotic vascular diseases and old-age dementias. Hyperhomocysteinemia is an independent risk factor for coronary artery disease and peripheral vascular disease, and is also associated with cerebrovascular disease; specifically, the risk of extracranial carotid atherosclerosis significantly increases in relation to Hcy levels. Hcy is a reliable marker of vitamin B12 deficiency, a common condition in the elderly which is known to induce neurological deficits including cognitive impairment; a high prevalence of folate deficiency has been reported in psychogeriatric patients suffering from depression and dementia. Both these vitamins occupy a key position in the remethylation and synthesis of S adenosylmethionine (SAMe), a major methyl donor in CNS; therefore, deficiencies in either of these vitamins lead to a decrease in SAMe and increase in Hcy, which can be critical in the aging brain. Another pathogenetic mechanism linking high Hcy levels to reduced cognitive performances in the elderly might be represented by excitotoxicity, since hyperhomocysteinemia may lead to an excessive production of homocysteic acid and cysteine sulphinic acid, which act as endogenous agonists of NMDA receptors. Considering the reasonably high prevalence in the general population of a genetic predisposition to a thermolabile form of the enzyme 5,10 methylenetetrahydrofolate reductase (MTHFR), hyperhomocysteinemia can be seen as the result of multiple genetic and environmental factors leading to vascular and/or neurodegenerative disorders where age-related involutive phenomena represent a common pathogenetic ground. Systematic studies in different psychogeriatric conditions monitoring Hcy levels and clinical features before and after vitamin supplementation are therefore highly recommended. PMID- 9359936 TI - A comparative study of factors related to carrying out physical activities of daily living (PADL) among 75-year-old-men and women in two Nordic localities. AB - The aim of this cross-sectional and cross-national study was to describe and compare the ability to carry out physical activities of daily living (PADL) and examine factors that might explain variation in this ability in two Nordic populations. Seven hundred and six men and women aged 75 from two populations (Glostrup, Denmark, and Jyvaskyla, Finland) were interviewed and given a laboratory examination in 1989-90. The ability to carry out the PADL activities was studied by interview. Tests were given to determine depressive symptoms, cognitive capacity, and selected physical and sensory performance domains. Four different regression models (men and women in Jyvaskyla and Glostrup) were used to analyze a number of variables describing physical and psychological health and performance related to the PADL. Knee extension strength and stair mounting height in three models (men and women in Jyvaskyla and women in Glostrup), and walking speed in one model (men in Glostrup) emerged as explanatory factors on the basis of the physical performance tests done. Sight, except in the women in Glostrup, hearing in the men in Jyvaskyla, and balance in the women in Glostrup also explained PADL functioning. In addition, symptoms of depression in the men in Glostrup, and symptoms of illness, except in the men in Jyvaskyla, and cognitive capacity in the men in Jyvaskyla emerged as explanatory factors in the regression models. There were, however, no major differences in the determinants of PADL functioning in the two Nordic populations of elderly people. Physical, psychological and sensory tests provide useful information, complementary to self reports regarding declining PADL functional capacity. PMID- 9359937 TI - Myocardial injury after hypoxia in immature, adult and aged rats. AB - We evaluated the abilities of isolated perfused hearts from immature (IM) (2.5-3 months), ADULT (11-13 months) and OLD (24-26 months) Fischer 344 rats to tolerate and recover from oxygen deprivation. Hearts were perfused at 60 mmHg for a 30 minute prehypoxic period with oxygenated buffer supplemented with 10 mM glucose (+insulin) and 2 mM acetate, then 30 minutes with substrate-free, hypoxic buffer gassed with 95% N2:5% CO2, and finally reoxygenated for an additional 45 minutes with the same buffer used during the prehypoxic period. During prehypoxia, all groups were similar in ventricular mechanical function, glycogen content, high energy phosphates (HEP), reduced glutathione (GSH), Ca+2 content, and mitochondrial state 3 rates. At the end of the hypoxic period, glycogen levels were similar and almost completely depleted in all groups, HEP were lower (p < 0.05) in ADULT vs other groups, mitochondrial state 3 rates were decreased (24%, p < 0.05) only in ADULT, and GSH was depleted by 34% in IM vs only 13% in OLD (p < 0.05). After 45 minutes of reoxygenation, IM and OLD had recovered 48% and 45% of their respective prehypoxic function which was two-fold greater than the 23% recovery by ADULT. Loss of cytosolic enzymes, an indicator of sarcolemmal damage, was estimated by measuring lactate dehydrogenase (LDH) release. LDH release and Ca+2 content during reoxygenation in IM were only about half of that observed in ADULT or OLD. We conclude that immature and aged hearts tolerate and recover from hypoxia better than hearts from adults, and that the sarcolemmal membranes of immature rat hearts are less susceptible to damage from hypoxic stress than those of either older group. PMID- 9359938 TI - Does fasting plasma insulin increase by age in the general elderly population? AB - The aim of this study was to examine the association of fasting plasma insulin with age. Insulin levels are influenced by obesity, physical inactivity, and medications, e.g., thiazide diuretics and beta adrenergic blockers. Further, comorbidity and pre-terminal conditions may confound the age-association of insulin. 1197 random subjects from four birth cohorts of the general aged population in southern Finland were examined, and followed for five years. Insulin levels at baseline tended to increase in men to the age of 75 years (mean 15.1 mU/L, SE 2.18), and in women to the age of 80 years (mean 15.9 mU/L, SE 1.14). The same association was seen among survivors in a five-year follow-up. These associations remained significant after controlling for obesity, physical inactivity and hyperinsulinogenic medications. PMID- 9359939 TI - Hypergravity and aging in Drosophila melanogaster. 9. Conditioned suppression and habituation of the proboscis extension response. AB - In a first experiment, the conditioned suppression of the proboscis extension response (PER) to sucrose was measured in young, middle-aged and old male Drosophila melanogaster flies living at either 1, 3 or 5 g. Flies were starved and then subjected to a learning task involving a sucrose stimulus, followed by an aversive one applied to their forelegs. In this learning task, flies learn to not extend their proboscis when walking on sucrose. Flies which have lived in hypergravity (HG) had a lower number of PER suppressions than 1 g ones, and this finding was mainly due to young and middle-aged flies. In a second experiment, the habituation of the PER was studied using as stimulation sucrose solutions 2 fold (first experiment), 4-fold (second one) or 8-fold (third one) higher than the individual sucrose threshold. Middle-aged and old flies habituated more slowly than young flies in the second and third experiments. In the third experiment, a decreasing speed of habituation was observed when gravity increased; this result was mainly due to young flies, and no gravity effect was observed in the other two age groups. This whole set of results suggests that HG kept flies do not age faster than 1 g ones, as far as these learning and habituation tasks are concerned. It seems possible that HG acts like a mild stress to which flies adapt; if applied for a long time, HG could induce a premature aging, as observed in the previous papers of this series. PMID- 9359940 TI - Cognitive deficits in the elderly: interactive theories and a study of environmental effects on psychometric intelligence. AB - Problems related to psychometric measures of intelligence are discussed with regard to both the general characteristics and metric properties (validity, reliability and sensibility) of mental tests, and interindividual differences (cultural background, education, life contents and age-cohorts). Currently used standard intelligence tests explore the structure of intelligence only in part, so a distinction must be made between true actual intelligence, potential inheritance of intelligence, and psychometrical or scored intelligence. The correct use of intelligence testing, however, does provide some relevant and objective information regarding the evolution of cognitive structure during adulthood and in relationship to aging. Cognitive performance in the elderly follows a downward curve that is not explained as a result of aging on physiological responses (i.e., reaction time delay, signal-noise ratio in the CNS, degenerative loss of cortical cells, etc.). Biologically based theories of intelligence cannot explain the large individual differences in cognitive abilities observed in subjects who have very similar physical characteristics. Cognitive approaches to intelligence enable us to better understand the causal factors of the cognitive deficits in the elderly, and an interactive model permits us to fully integrate both the individual differences in cognitive abilities and the large consistency in performances. We compared the cognitive performances of two groups of elderly subjects, ranging in age from 65 to 97 years; we observed some statistically significant effects on cognitive deficit that could be explained as fully deriving from emotional and extra-cognitive responses to environmental changes. PMID- 9359942 TI - Dietary restriction in rhesus monkeys: lymphopenia and reduced mitogen-induced proliferation in peripheral blood mononuclear cells. AB - Dietary restriction (DR) markedly extends mean and maximal life span, and retards the rate of biological aging in rodent models; however, it is unknown if these results occur in primate species. The purpose of the current study was to investigate selected immunologic outcomes in Rhesus monkeys subjected to DR for a period of seven years. Similar to observations in mice on DR, lymphopenia occurred in the restricted monkeys. Compared to normally fed controls, the mitogen-induced proliferative responses of peripheral blood mononuclear cells (PBMC) were reduced in monkeys subjected to DR very early in life (up to 1 year), but not in others restricted in young adulthood (3-5 years). These data indicate that lymphopenia is a shared occurrence in rodents and primates on DR. However, the mitogen-induced proliferative data accumulated in rodents and primates cannot now be compared because PBMC have not been studied long enough or in comparable detail in primates fed restricted diets. PMID- 9359941 TI - Gemcitabine: safety profile and efficacy in non-small cell lung cancer unaffected by age. AB - Gemcitabine, a novel anticancer agent, was demonstrated to be well tolerated in both elderly and younger patients. Safety data were collected from 18 completed clinical studies (790 patients) in a variety of solid tumor types. All studies used a starting dose of 800-1250 mg/m2 administered once a week for 3 weeks followed by a week of rest. Patients were initially divided using a cut-off age of 65 years, and subsequently using a cut-off age of 70 years. Gemcitabine was well tolerated by patients of all ages, with few clinically meaningful differences between the age groups. Gemcitabine was also found to be as efficacious in older patients as in younger ones. Efficacy data was collected from four studies (329 evaluable patients) in non-small cell lung cancer with consistent response rates of 20%. When patients were divided into two groups, those aged below 70 years and those 70 years and above, the response rates were 19.0% (95% C.I., 14.6-23.4) and 25.0% (95% C.I., 10.0-40.0) respectively. In conclusion, elderly patients should benefit from gemcitabine treatment. PMID- 9359943 TI - Liposomal formulation of amphotericin B approved for marketing. PMID- 9359944 TI - Medicare reforms affect hospitals, outpatient settings. PMID- 9359945 TI - North Carolina board of pharmacy releases figures from mandatory reports of drug related deaths. PMID- 9359946 TI - Isolates of partially vancomycin-resistant S. aureus reported in United States. Findings follow similar report in Japan. PMID- 9359947 TI - Erythromycin resistance in Finland declines after reduction in macrolide use. PMID- 9359948 TI - Report unveils new approach to nutrient recommendations. Higher calcium intakes backed for many. PMID- 9359949 TI - Survey shows continued need to educate public about folic acid and birth defects. PMID- 9359950 TI - Improving drug use in a capitated program for the poor. PMID- 9359951 TI - Guiding patients to better pain relief. PMID- 9359952 TI - Slowing the emergence of multidrug-resistant pathogens. PMID- 9359953 TI - Management of acute extrapyramidal effects induced by antipsychotic drugs. AB - The management of acute extrapyramidal effects (EPEs) induced by antipsychotic drugs is reviewed. EPEs associated with antipsychotics include acute dystonias, pseudoparkinsonism, and akathisia. Acute dystonias consist of abnormal muscle spasms and postures and usually occur three to five days after antipsychotic therapy begins or the dosage is increased. Acute dystonias should be treated with anticholinergic medications or benzodiazepines. Antipsychotic-induced pseudoparkinsonism has the same clinical appearance as idiopathic parkinsonism. Symptoms generally appear within the first three months. Pseudoparkinsonism is managed by lowering the anti-psychotic dosage or by adding an anticholinergic agent or a mantadine; switching to a low-potency agent or an atypical antipsychotic may also help. Akathisia is characterized by subjective feelings of restlessness and anxiety and objective signs of motor activity, such as inability to sit still. This EPE appears days to weeks after antipsychotic exposure begins and can be difficult to manage. If reduction of the antipsychotic dosage or a switch to a less potent antipsychotic is not practical or effective, an anticholinergic, beta-blocker, or benzodiazepine may be added. Lipophilic beta blockers, especially propranolol and metoprolol, appear to be the most effective treatments. Anticholinergic agents are commonly given to prevent acute dystonias, especially in high-risk patients, but long-term prophylaxis is controversial. Atypical antipsychotics may have less potential to induce EPEs. Options in the management of antipsychotic-associated EPEs include using the lowest effective dosage of antipsychotic, treating the reactions with medications, and changing the antipsychotic to one with less potential for inducing EPEs. PMID- 9359954 TI - Patients' self-reported functional status after granisetron or ondansetron therapy to prevent chemotherapy-induced nausea and vomiting at six cancer centers. AB - Patient functional status after administration of either granisetron or ondansetron to prevent acute chemotherapy-induced nausea and vomiting (CINV) was studied. Pharmacists and nurses from six cancer centers distributed Functional Living Index-Emesis (FLIE) questionnaires to 115 outpatients receiving either granisetron or ondansetron for prevention of CINV. The emetogenic potential of each patient's chemotherapy regimen was high, moderately high, or moderate. Immediately before and 72 hours after chemotherapy, each patient rated his or her reaction to each of 18 items on the questionnaire on a 7-point scale. Possible scores ranged from 18 to 126, with higher scores indicating higher levels of functioning. The occurrence of nausea in the granisetron group was 40.0% compared with 43.2% in the ondansetron group; the occurrence of vomiting was 18.8% in the granisetron group and 11.1% in the ondansetron group. Patients who received highly emetogenic chemotherapy had significantly lower scores on the FLIE after chemotherapy than before. Patients with both nausea and vomiting reported a much higher negative impact on functional status after chemotherapy than those with nausea only. The mean prechemotherapy and postchemotherapy FLIE scores were 124.2 and 110.4 for granisetron and 124.9 and 111.9 for ondansetron. Granisetron and ondansetron did not differ significantly in their effect on functional status reported by patients before and 72 hours after receiving cancer chemotherapy. PMID- 9359955 TI - Effects of ingredients on stability of captopril in extemporaneously prepared oral liquids. AB - The stability of captopril in several extemporaneously prepared oral liquid formulations was studied. Captopril 1-mg/mL oral liquid formulations were prepared from either powder or tablets in two grades of water, syrup, methylcellulose, and edetate disodium. The liquids were stored at 5 degrees C in amber glass containers, and samples were removed at intervals up to 30 days for assay of captopril concentration by stability-indicating high-performance liquid chromatography. The pH of the formulations remained fairly stable for 30 days. In general, captopril was more stable in formulations containing captopril from tablets than from powder. Captopril in formulations in which the only vehicle was highly purified water was slightly but not significantly more stable than in formulations made with sterile water for irrigation. Formulations made with undiluted syrup were more stable than formulations in which water was used to dilute syrup or formulations containing methylcellulose. The formulations containing edetate disodium were much more stable than those that lacked this component. The stability of captopril 1 mg/mL in oral liquid formulations was influenced by the captopril source (tablets versus powder) and by the presence of syrup, methylcellulose, and edetate disodium. Captopril in a preparation made with tablets and undiluted syrup was stable for 30 days at 5 degrees C, and the formulation should be palatable. PMID- 9359956 TI - Fatal hyperphosphatemia after oral phosphate overdose in a premature infant. PMID- 9359957 TI - Mathematical modeling of pharmacy systems. AB - Mathematical modeling and its potential applications in pharmacy are discussed. A model is a simplified representation of the real world. As an experimental approach, modeling minimizes expense, risk, and disruption, but its validity can be hard to ascertain. Mathematical models describe numerically the relationships among elements of a system and are a powerful tool in making decisions affecting that system. There are two types of mathematical models: analytical models, which directly describe the relationships between system inputs and outputs using mathematical equations (such as pharmacokinetic models), and simulation models, which involve the replication, usually with a computer, of events as they occur in the real world. Analytical models are easier to develop but are not appropriate for describing highly complex systems. In continuous-time simulation, the system is represented as an uninterrupted flow of material; in discrete-event simulation, it is assumed that events occur only at distinct times. Various simulation programs are commercially available. The stages of a mathematical modeling study are (1) formulate the problem, (2) determine the model's structure, (3) collect and analyze initial data, (4) develop the model further, (5) validate the model, (6) experiment using the model, and (7) use the results. There have been many applications of modeling in health care, but relatively few have involved the study of pharmacy systems. Mathematical modeling offers pharmacists a low-risk, low-cost tool for aiding decisions about pharmacy systems by predicting alternative futures. PMID- 9359958 TI - Focus group on pharmacy and managed care. AB - The participants agreed that integrated health systems of the future will provide the full continuum of care for patients. The characteristics of individual systems will be influenced by the basic elements the system controls and maintains inhouse and the elements that are outsourced. The challenge to pharmacists in these systems will be to ensure that key decision-makers have accurate information about the value of pharmacy and the need to include pharmacists on the care team. The medication-use process and the formulary system will be tied to disease-specific care plans or treatment protocols. Pharmacists will have a greater role in overall disease management. They will be involved with the patient before an office visit and will aggressively follow the patient to prevent or slow disease progression. Pharmacy managers have identified a number of core competencies their staffs must have. One participant summed these up as outstanding clinical knowledge, exceptional communication skills, and common sense. PMID- 9359959 TI - The health care puzzle: where does pharmacy fit? PMID- 9359960 TI - Simple approach to dosage adjustment in patients with renal impairment. PMID- 9359961 TI - Methylphenidate for depression in the elderly, medically ill patient. PMID- 9359962 TI - Propofol infusion and nutritional support. PMID- 9359963 TI - Procedures for preparing injectable medications for latex-sensitive patients. PMID- 9359964 TI - Confirmation and location of the hybrid zone between wild populations of Macaca tonkeana and Macaca hecki in central Sulawesi, Indonesia. AB - Reports of hybridization between Macaca tonkeana and Macaca hecki were investigated in Central Sulawesi, Indonesia. We defined sets of morphological traits that were diagnostic for M. tonkeana and M. hecki and then located an areas where animals had intermediate or mosaic features. Hybridization as indicated by morphology was detected between M. tonkeana and M. hecki. The hybrid zone appeared to be strongly centered at the road that crosses the isthmus of Central Sulawesi from Tawaeli to Toboli. Macaques in this region were not morphologically uniform; animals from the western area of the Tawaeli-Toboli road resembled M. hecki, while animals from the eastern area resembled M. tonkeana. The hybrid zone was found to be smaller than previously thought, with maximum dimensions of approximately 15 and 7.5 km. Clines for diagnostic morphological features were broadly coincident, suggesting that the hybrid zone originated by secondary contact. Analysis of three museum specimens collected in 1916 provided evidence that the hybrid zone has been in existence since at least then. The narrow width of the hybrid zone, along with its age, suggested that some prezygotic or postzygotic barrier must exist to full introgression between M. tonkeana and M. hecki. PMID- 9359965 TI - Seasonal variation in activity and diet in a small-bodied folivorous primate, Hapalemur griseus, in southeastern Madagascar. AB - How small-bodied (500-1,200 g) folivorous prosimian primates cope with large amounts of foliage in their diet seasonally has yet to be determined for many species such as Hapalemur griseus, which specializes on bamboo. To address this issue, we present results on seasonal variation in activity and diet from a wild group of H. griseus in southeastern Madagascar. Throughout the study (which was conducted from July-November 1994 and July 1995-February 1996), H. griseus primarily fed on new growth from three species of bamboo: two species of liana bamboo and Cephalostachyum perrieri. Bamboo species were used in different ways seasonally; liana bamboo was consumed more during the dry, cool season, and C. perrieri was eaten more often during the wet, warm season. H. griseus also spent more of their time feeding and traveling than nocturnal folivores of similar body size during the dry season. During the warm wet season, H. griseus decreased the amount of time spent feeding and traveling and rested more often. We hypothesize that seasonal changes in activity may be primarily related to the distribution and availability of food sources and/or reproductive cycles. PMID- 9359966 TI - Effects of duration of separation on responses to mates and strangers in the monogamous titi monkey (Callicebus moloch). AB - Adult male and female titi monkeys form an intense social bond characterized by high levels of affiliative interactions between pairmates and agonistic responses to strangers. In natural settings, separation between mates can vary from brief periods, as when mates drift apart during feeding, to permanent separation, occasioned by desertion or death. In this study we asked how different durations of separation altered the behavior of male and female titi monkeys (Callicebus moloch). We compared the effects of brief separation such as might occur incidentally during feeding (1-2 h) with prolonged separation such as might occur if one partner died or deserted (5 days). Effects were observed during a 30 min reunion of pairmates or during a 30 min encounter with a stranger of the opposite sex. Following brief separation, interactions between mates and between strangers clearly differed in measures of affiliation, but not in behaviors indicative of arousal. Following prolonged separation, measures of arousal increased with both mated pairs and strangers. Females tended to interact more readily with a stranger following prolonged separation than after brief separation, but interactions between mates were essentially unchanged and differed substantially from those between strangers. The data suggest that the pair bond persists in titi monkeys after prolonged social isolation, despite increased interest in interacting with potential new partners. PMID- 9359967 TI - Special relationships instead of female dominance for redfronted lemurs, Eulemur fulvus rufus. AB - Most lemurs yet studied in detail exhibit some mode of adult female social dominance over males. The known exception, a brown lemur subspecies known as rufous or redfronted lemurs (Eulemur fulvus rufus), forms multimale-multifemale social groups within which unambiguous dominance relations are not observed among adults. Resting groups of redfronted lemurs consistently include huddling adult male-female pairs whose males selectively scentmark and rub their heads in the scentmarks of their female huddling partners. Quantitative observations confirmed that some of these male-female pairs maintain special relationships satisfying all criteria originally developed in research on cercopithecine monkeys. Observations before, during, and after mating season, intergroup encounters, male transfers, and changes in male-female affiliations illuminated developmental and functional aspects of male-female partnerships. Each adult female in two semi free-ranging study groups shared high rates of association, grooming, and agonistic support and low rates of agonistic interaction with one unrelated or distantly related adult male partner. Such affinity characterized small proportions of adult male-female relationships. Several males directed not only support but also aggression toward adult females with whom they sought to affiliate. All bonded males sought to copulate with their partners, and some appeared to ignore estrus in nonpartners. All females accepted copulation attempts from partners and some seemed to prefer their partners as mates. Partial synchronization of brief estrus periods together with concealed ovulation appeared to minimize chances for polygynous mating. Results support the view that the male-female pair is the fundamental social unit of E. fulvus and suggest that female partnership with individual males obviates dominance behavior, including female dominance, in this lemurid primate. PMID- 9359968 TI - Adoption by captive parturient rhesus macaques: biological vs. adopted infants and the cost of being a "twin" and rearing "twins". AB - Four rhesus macaque (Macaca mulatta) mothers each spontaneously adopted and reared an abandoned, unrelated neonate in addition to their own neonate. Data on relative time spent in maternal contact and who maintained proximity were collected for the biological and adopted "twins" and singleton control infants using focal animal sampling. Infant weight gain and the subsequent conception history for each mother were obtained for the following year. Biological infants spent more time in maternal contact than their adopted "twin" siblings. When in contact with their mothers, biological "twins" spent more time in the ventro ventral position and more ventral time alone than adoptees. Mothers initiated more contacts with their biological infants than their adopted infants, suggesting these differences may be due to differential maternal behavior. "Twins" gained weight at a slower rate than singletons, and mothers rearing "twins" produced significantly fewer offspring the following season. PMID- 9359969 TI - Chromosomal similarities and differences between tamarins, Leontopithecus and Saguinus (Platyrrhini, Primates). AB - The karyotypes of two taxa of genus Leontopithecus (rosalia and chrysomelas) are studied. Their G-, C- and NOR-banding patterns are compared with those of representatives of the genus Saguinus to determine chromosomal similarities and differences between the two genera and thus contribute to explaining phylogenetic relations between the tamarins. Leontopithecus, like the Saguinus, presents 2n = 46, 14 autosomes plus the Y acrocentric and 30 autosomes plus the X biarmed. No chromosomal rearrangement distinguishes the karyotypes of the representatives of genus Leontopithecus or genus Saguinus. The two genera are distinguished from each other by a paracentric inversion and pericentric inversions on at least four pairs of acrocentric autosomes, displacing the NORs of the small short arms in Leontopithecus to the proximal region of the long arms in Saguinus or vice versa. The tamarins are also distinguished by the distribution of noncentromeric constitutive heterochromatin. The data obtained indicate that the two tamarin genera are closely related chromosomally, suggesting that they probably originated from the same ancestral branch. PMID- 9359970 TI - Subsensitivity of adenylyl cyclase-coupled receptors on mononuclear leukocytes from drug-free inpatients with a major depressive episode. AB - Previous studies have demonstrated blunted beta-adrenergic responsivity in leukocytes from depressed patients. We sought to determine if this blunted cyclic adenosine monophosphate (AMP) response is specific for beta-adrenergic receptors (homologous), or whether other adenylyl cyclase-coupled receptors are also involved (heterologous), in order to localize this effect at the level of the receptor versus the coupling protein or the transducer, adenylyl cyclase. We studied adenylyl cyclase-mediated responses in peripheral blood mononuclear cells from 95 drug-free patients with a major depressive episode and 69 healthy controls. We found a similar degree of decrease in the peak cyclic AMP response to activation of the beta-adrenergic receptor (28%) and the prostaglandin receptor (34%) in the depressed patients, which indicated heterologous desensitization. Forskolin cyclic AMP responses were not blunted. Blunting of cyclic AMP responses to isoproterenol did not appear to correlate with levels of plasma norepinephrine and epinephrine or hypothalamic-pituitary-adrenocortical function. The absence of a decrease in the peak forskolin-generated cyclic AMP response, which involves direct activation of adenylyl cyclase, suggests an abnormality at the level of the coupling protein in these adenylyl-coupled receptors in depressed patients. Future studies need to determine whether this leukocyte signal transduction defect in depression also involves brain adenylyl cyclase-coupled receptors. PMID- 9359971 TI - Increased levels of a mitochondrial DNA deletion in the brain of patients with bipolar disorder. AB - Mutations in mitochondrial DNA (mtDNA) have been implicated in the pathophysiology of affective disorders. To examine possible pathophysiological significance of mtDNA deletions in bipolar disorder, the concentration of the 4977-base-pair deletion in mtDNA in the autopsied brains of 7 patients with bipolar disorder, 9 suicide victims, and 9 controls was examined using a quantitative polymerase chain reaction method. The ratio of deleted to wild-type mtDNA in cerebral cortex was significantly higher in patients with bipolar disorder [0.23 +/- 0.18 (mean +/- SD)%] compared with that in age-matched controls (0.06 +/- 0.07%, p < 0.05). This result supports a hypothesis that mtDNA deletions may play a role in the pathophysiology of bipolar disorder. PMID- 9359972 TI - Expanded CAG/CTG repeats in bipolar disorder: no correlation with phenotypic measures of illness severity. AB - The hypothesis that expanded trinucleotide repeats (TNRs) contribute to the pathogenesis of bipolar disorder has received strong support from recent studies showing that, on average, bipolar patients carry larger repeat sequences of the TNR motif CAG/CTG than do controls. It has been postulated that intergenerational expansion of a TNR may be responsible for the tendency for age of onset to become earlier in younger generations (anticipation) observed in some bipolar pedigrees, and that length polymorphism may account for variability in clinical phenotype. We have used the method of repeat expansion detection to examine these predictions in a sample of 133 Caucasian DSM-III-R bipolar I probands from the British Isles. We found no evidence to support the notion that CAG/CTG TNR genes are major determinants of phenotypic severity or age at onset in the population examined, and conclude that for most cases of bipolar disorder TNR genes may operate as susceptibility genes rather than as single genes of major effect. PMID- 9359973 TI - The effect of repeated human corticotropin-releasing hormone administration on dexamethasone-suppressed pituitary-adrenocortical activity in healthy subjects. AB - A dexamethasone suppression test (DST) using a dosage of 1.5 mg dexamethasone was administered two times in randomized order to 10 healthy male subjects. From 2300 hours to 0700 hours subjects were injected repeatedly with either increasing dosages of human corticotropin-releasing hormone (hCRH) or 0.9% saline. In comparison to saline administration, in which cortisol levels remained suppressed, the time course of cortisol concentrations with hCRH stimulation showed a biphasic secretory pattern. According to a criterion level of a minimum of 40 ng/mL plasma for nonsuppression, the majority of the subjects changed their DST status to nonsuppression with hCRH. Adrenocorticotropic hormone secretion also differed significantly between saline and hCRH administration. During stimulation with hCRH, plasma dexamethasone levels were slightly and nonsignificantly reduced in the morning hours. Our results indicate that repeated dosages of hCRH impair the dexamethasone-induced suppression in man and support an involvement of CRH also in mediation of the DST nonsuppression during depressive illness. PMID- 9359974 TI - Dopamine function in obsessive-compulsive disorder: growth hormone response to apomorphine stimulation. AB - Indirect observations suggest that the dopaminergic system may be involved in the pathophysiology of obsessive-compulsive disorder (OCD). The dopaminergic function of 15 patients with OCD and 15 age/sex-matched controls was evaluated by measuring the growth hormone (GH) responses to stimulation with the dopaminergic agonist apomorphine (APO), which increases growth hormone-releasing hormone (GHRH), GH, and somatomedine C (SMD-C) secretions. Therefore, we measured basal plasma GH and SMD-C concentrations and GH responses to GHRH stimulation to exclude that a downstream pathology of the somatotropic axis could obscure the significance of the results of the APO test. The response of prolactin (PRL) to APO inhibition were also measured. Basal plasma levels of GH, SMD-C, and PRL, GH responses to GHRH stimulation, and PRL responses to APO inhibition did not differ in the two groups of subjects. GH responses to APO stimulation were blunted in obsessive-compulsive (OC) patients. The emetic response to the same stimulation was stronger in patients than in controls. These responses suggest that in our OC patients there is a dysregulation of the dopaminergic system, which is possibly expressed in different ways in the various areas of the central nervous system. PMID- 9359975 TI - Depression and dementia in relation to apolipoprotein E polymorphism in a population sample age 75+. AB - The aim of this study was to define the co-occurrence of depression and dementia in relation to apolipoprotein E (APOE) polymorphism. Physicians extensively examined 806 persons aged 78 years and over. DNA was extracted from peripheral white blood cells, and APOE genotype was determined using a microsequencing method on microtiter plates. The prevalence of dementia was 22.8% and was found to increase with the number of epsilon 4 alleles present. Depression was found in 11.4% of the demented subjects compared to 3.5% of the nondemented subjects. The overrepresentation of depression in demented subjects was found for each of the common genotypes. Depression was not strongly associated with APOE polymorphism. In spite of the association between dementia and APOE polymorphism, as well as dementia and depression, there was no association between APOE polymorphism and depression. PMID- 9359976 TI - Which depressive symptoms are related to which sleep electroencephalographic variables? AB - Sleep complaints and electroencephalographic (EEG) sleep abnormalities are associated with risk for new onset depression, illness severity, treatment outcome, and vulnerability for recurrence of depression. The aim of this study was to evaluate the strength of association between EEG sleep measures and depression symptoms, and to identify the variables that account for the majority of the association. Depression ratings from the Hamilton Rating Scale for Depression and the Beck Depression Inventory and polysomnographic measures were examined in 361 adult outpatients with major depressive disorder. Canonical correlation and serial multiple regression analyses were used to determine the associations between depressive symptoms and sleep measures. Canonical correlation showed a unidimensional relationship between depressive symptoms and sleep measures (R = .55, p < .05). Fifteen depression items and nine sleep measures accounted for 95% of the correlation. Depression variables encompassed a core set of mood, neurovegetative, and cognitive symptoms. Sleep variables were primarily related to delta EEG activity, and this may be reflective of impaired sleep "drive" or heightened arousal during sleep. PMID- 9359977 TI - Major depression and cardiac autonomic control. AB - We investigated autonomic control of heart rate in patients with major depression, melancholic type. Twenty-three depressed inpatients who were being treated with tricyclic antidepressants and 23 depressed patients who were taking no medications were compared with age- and sex-matched control groups on resting cardiac vagal tone and heart rate. In unmedicated depressed patients, cardiac vagal tone was comparable to that of control subjects, but heart rate was significantly higher. This increase in heart rate may have been due to sympathetic activation caused by anxiety, since the depressed patients were significantly more anxious than the control subjects. Medicated patients exhibited diminished cardiac vagal tone and higher heart rate than unmedicated patients and controls. This was probably due to the anticholinergic effects of the antidepressants. Our findings suggest that cardiac vagal tone is not lower than normal in patients with depression, melancholic type. PMID- 9359978 TI - Preliminary comparison of behavioral and biochemical effects of chronic transcranial magnetic stimulation and electroconvulsive shock in the rat. AB - To confirm the assumption that repetitive rapid-rate transcranial magnetic stimulation (TMS) induces the functional and structural changes analogous to those which are evoked during electroconvulsive shock (ECS), we compared now the effects of treatments with TMS and ECS on the behavioral responses in rats. We also tested the reactivity of the cyclic adenosine monophosphate (AMP) generating system in cerebral cortical slices. TMS similarly to ECS shortened the immobility time in the forced swimming test and produced a depression of responsiveness of the noradrenaline-stimulated cyclic AMP generating system, although the significance of the latter effect was borderline. In contrast to ECT, TMS produced no such immediate behavioral effects as analgesia and depression of the early phase of locomotor activity. The data suggest that TMS produces in rats some responses that are regarded as predictive for antidepressant activity, similar to those produced by ECS, but less adverse effects. PMID- 9359979 TI - The dexamethasone suppression test and treatment outcome in elderly depressed patients participating in a placebo-controlled multicenter trial involving moclobemide and nortriptyline. AB - The dexamethasone suppression test (DST) was conducted in 95 elderly DSM-III-R depressed patients randomized for treatment with moclobemide (MOC; 400 mg daily), nortriptyline (NT; 75 mg daily), or placebo (PBO) in a 7-week double-blind multicenter study. Patients were assessed weekly using various clinical scales, including the 17-item Hamilton Depression Rating Scale. The DST was administered at baseline and at the end of treatment. At baseline, no relationship was found between DST status and the various clinical scales used. At the end of treatment, suppressors (DST-) had significantly improved clinical ratings compared to nonsuppressors (DST+), and were mostly found among those treated with NT (71%) as compared to MOC (41%) or PBO (33%) (p < .03). On the other hand, baseline DST measures influenced treatment outcome; DST+ patients had a greater number of treatment responders to NT (48%) than MOC (19%) or PBO (20%) (p < .07). For DST- patients, the situation was reversed: NT, 7%; MOC, 31%. Postdexamethasone cortisol levels were lower in MOC responders (p < .07). An interaction was found between DST and drug-specific response. The DST may be a useful adjunct for predicting and evaluating the outcome of antidepressant therapy. PMID- 9359980 TI - Ritanserin in the treatment of cocaine dependence. AB - Sixty-five cocaine-dependent subjects were enrolled into a 10-week randomized, double-blind study to determine the safety and efficacy of the serotonin-2 receptor antagonist, ritanserin (10 mg/day), in reducing cocaine consumption and craving. All subjects also participated in a structured intensive outpatient psychosocial program. Seventy-three percent of the participants completed the treatment program and follow-up. Subjects experienced a significant reduction in craving: 66.4% and 32.5% for the placebo and ritanserin groups, respectively. These reductions in craving were not paralleled by substantial decreases in cocaine use. Self-reported cocaine use was less frequent in the placebo group; paradoxically, blood levels of its metabolite, benzoylecgonine, were also higher although insignificantly so. Generally, ritanserin was well tolerated but significantly prolonged the QTc interval on the electrocardiogram. This outpatient program is effective at maintaining cocaine-dependent individuals in treatment and reducing craving. Ritanserin (10 mg/day) is not an efficacious adjunct to psychosocial treatment for cocaine dependence. PMID- 9359981 TI - Neuroreceptor subunit genes and the genetic susceptibility to Gilles de la Tourette syndrome. AB - Segregation studies have shown that Gilles de la Tourette Syndrome (GTS) is probably transmitted as an autosomal dominant gene disorder and can therefore be studied by classical linkage analysis to identify susceptibility loci. Many neurotransmitter systems have been implicated in the etiology of GTS. Most recently the alpha-1 subunit of the glycine receptor etiologically responsible for hyperekplexia has been hypothesized as the cause of the susceptibility to GTS. Because of this and the high concentration of other neuroreceptor genes at 5q33-35, it was decided to study this region and the associated gene cluster on chromosome 4p12-16 in a large British kindred multiply affected with GTS and chronic motor tics. The genotypes of the microsatellite markers at these loci were determined by polymerase chain reaction. The allele data were analyzed using both parametric and nonparametric methods. Approximate multipoint maps were constructed across the regions of interest using FASTLINK. All of the lod scores produced were negative, showing no evidence of linkage to GTS in the family studied. The multipoint maps showed good exclusion across these regions. The glycine receptor gene responsible for hyperekplexia and the other neuroreceptor genes examined in this paper are not involved in the etiology of GTS in this large pedigree. PMID- 9359982 TI - The Altman Self-Rating Mania Scale. AB - We report on the development, reliability, and validity of the Altman Self-Rating Mania Scale (ASRM). The ASRM was completed during medication washout and after treatment by 22 schizophrenic, 13 schizoaffective, 36 depressed, and 34 manic patients. The Clinician-Administered Rating Scale for Mania (CARS-M) and Mania Rating Scale (MRS) were completed at the same time to measure concurrent validity. Test-retest reliability was assessed separately on 20 depressed and 10 manic patients who completed the ASRM twice during washout. Principal components analysis of ASRM items revealed three factors: mania, psychotic symptoms, and irritability. Baseline mania subscale scores were significantly higher for manic patients compared to all other diagnostic groups. Manic patients had significantly decreased posttreatment scores for all three subscales. ASRM mania subscale scores were significantly correlated with MRS total scores (r = .718) and CARS-M mania subscale scores (r = .766). Test-retest reliability for the ASRM was significant for all three subscales. Significant differences in severity levels were found for some symptoms between patient ratings on the ASRM and clinician ratings on the CARS-M. Mania subscale scores of greater than 5 on the ASRM resulted in values of 85.5% for sensitivity and 87.3% for specificity. Advantages of the ASRM over other self-rating mania scales are discussed. PMID- 9359983 TI - Progesterone and adolescent suicidality. PMID- 9359984 TI - Harm avoidance dimension of the Tridimensional Personality Questionnaire and serotonin-1A activity in depressed patients. PMID- 9359985 TI - Persistent analgesia in former opiate addicts is resistant to blockade of endogenous opioids. PMID- 9359986 TI - Fine structural alterations of blood platelets in depression. PMID- 9359987 TI - Studies on some trace and minor elements in blood. A survey of the Kalpakkam (India) population. Part I: Standardization of analytical methods using ICP-MS and AAS. AB - Blood is one of the widely used specimens for biological trace element research because of its biological significance and ease of sampling. We have conducted a study of the blood of the Kalpakkam township population for trace and minor elements. For this purpose, analytical methods have been developed and standardized in our laboratory for the elemental analysis of blood plasma and red cells. Inductively coupled plasma-mass spectrometry (ICP-MS), a relatively new technique, has been applied for the analysis of trace elements. Details regarding spectral interference and matrix interference encountered in the analysis of blood and the methods of correcting them have been discussed. Flame atomic absorption spectrometry (AAS)/atomic emission spectrometry (AES) has been applied for the determination of minor elements. Precision and accuracy of these methods have also been discussed. PMID- 9359988 TI - Studies on some trace and minor elements in blood. A survey of the Kalpakkam (India) population. Part II: Reference values for plasma and red cell, and correlation with coronary risk index. AB - Since data on the trace element levels in Indian population are lacking, we chose to conduct a survey of the Kalpakkam township population. People in the age group 40-55 were included in this study. Reference values for trace and minor elements of the blood of the Kalpakkam population were arrived at by carrying out the analysis of plasma and red cells of healthy subjects of the Kalpakkam population. Although the "reference values" for many elements were found to be normal and comparable to values available in the literature, slight deficiency with respect to Se was noticed. Subjects with high coronary risk index were also included in the study to assess the possible correlation of elemental and lipid profile. A study of box plots showed that the elements Se, Mg, Na, K, and Fe show significant differences between "high risk" coronary risk index (CRI > 5) and "no risk" (CRI < 4.5). In the plasma, the levels of Mg, Na, and K were found to be less in the high-risk group. In red cells, the amount of Se, Fe, and K were found to be significantly less in the "high-risk" group as compared to the "no-risk" group. PMID- 9359989 TI - Studies on some trace and minor elements in blood. A survey of the Kalpakkam (India) population. Part III: Studies on dietary intake and its correlation to blood levels. AB - In our studies on elemental levels in blood of the Kalpakkam population, it was found that the reference values for many elements were normal, but some deficiency with respect to Se was noticed. As a followup study, the dietary ingredients of the local population were analyzed for trace and minor elements to assess the dietary intake of these elements. Details of the analytical methods developed using the technique of inductively coupled plasma-mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS) have been described. The dietary intake of many of these trace and minor elements were found to be quite adequate according to the recommended dietary allowance (RDA) levels prescribed, except for Se and Zn. The dietary intake of Se was found to be in the range 20-50 micrograms/d (as opposed to the RDA of 50-200 micrograms/d), whereas the intake of Zn was found to be in the range 8-10 mg/d (as opposed to the RDA of 15 mg/d). Although the deficiency of Se intake was reflected in the blood, that of Zn was not, probably owing to the high level of homeostasis for this element. Fish and egg were found to be rich sources of Se, followed by cereals and pulses, which were found to be the major sources of Zn. PMID- 9359990 TI - Hepatotoxicity of diazepam. Structural and trace metal studies in rat. AB - Studies of effects of diazepam on liver parenchyma are very scanty. In this study, adult albino rats were treated with diazepam in two different doses (0.25 mg and 0.30 mg/kg body wt) daily for 30 and 60 d. Through light microscopy and electron microscopy, prenecrotic and necrotic changes were noted in the high-dose group. Trace metal analysis indicated that zinc (Zn) was reduced by 30 and 60 day under both the doses, whereas iron (Fe) and copper (Cu) were reduced significantly in these groups only after 60 d of treatment. This reduction in metal contents may have some correlations with necrotic changes in liver parenchyma. PMID- 9359991 TI - Effect of selenium on lead-induced alterations in rat brain. AB - The effects of lead (Pb) and selenium (Se) interactions on central nervous system (CNS) functions were seen in adult rats by both biochemical and histologic pathological alterations. Pb administration of 20 mg/kg body wt for 8 wk showed degenerative changes only in the cerebral cortex. The changes in the cerebellar regions were not significant. Biochemically a marked decrease in the DNA, RNA, and protein content was seen following lead treatment. These decreases were significant in both the regions of the brain. During the concomitant administration of Pb and Se, the alterations in the transverse section of cerebral cortex showed only marginal changes. The values of DNA and RNA content showed significant improvement in both regions of the brain compared to the Pb treated group. PMID- 9359992 TI - Comparative effects of selenite and selenite on the glutathione-related enzymes activity in pig blood platelets. AB - The effects of inorganic selenium (Se) compounds (sodium selenite and selenate) on the activities of glutathione-related enzymes (glutathione peroxidase, glutathione-S-transferase [GST] and glutathione reductase [GR]) in pig blood platelets were investigated in vitro. GST activity in blood platelets treated with 10(-4)M of selenite was reduced to 50%, whereas no decrease GST activity was observed after the treatment of platelets with the same dose of selenate. In platelets incubated with physiological doses (10(-7) and 10(-6)M) of Se compounds, the activity of glutathione peroxidase (GSH-Px) was enhanced (about 20%). GR activity after the exposure of platelets to tested Se compounds was unaffected. PMID- 9359993 TI - Urine levels of aluminum after drinking tea. AB - A microwave-assisted acid digestion procedure coupled with a graphite furnace atomic absorption method has been applied in the determination of aluminum (Al) in urine to verify the correlation of free forms of Al in tea infusions and urinary excretion of Al. Significant urinary Al excretion has been found in 24-h urine of four volunteers after tea drinking. However, the difference in amount of Al excretion in urine between the consumption of Oolong (black tea) and Long-Jin (green tea), each of them with unique Al contents and species, was not significant. These findings indicated that the high levels of free Al species in tea infusions did not result in significant change in urinary excretion of the metal, possibly owing to the transformation by ligands present in food and the gastrointestinal tract (GIT). However, it could not be assumed that there was no big difference in absorption of the metal in the human body if fractions of consumed Al retained in the body or excreted by bile or feces were considered. PMID- 9359994 TI - Calcium antagonists--looking stronger by the day. PMID- 9359995 TI - Trends in left ventricular function over three years in the Tecumseh Study. AB - The relationship between blood pressure and left ventricular diastolic function was examined in participants of the Tecumseh Blood Pressure study. When subjects were divided into three blood pressure groups according to blood pressure levels 3 years apart, it was found that subjects who were had sustained "hypertension" at both time points (SH) had a decreased early/late diastolic filling rate (E/A ratio) compared to subjects who were hypertensive at only one of the timepoints (OH) and those who were consistently normotensive (NN) (1.71 +/- 0.02 NN vs 1.55 +/- 0.05 OH, (p < 0.0001) vs 1.56 +/- 0.07 SH, (p < 0.04)). This relative order was maintained when the second estimation of diastolic filling was performed 3 years later, but the E/A ratio had decreased significantly in all groups (1.54 +/ 0.01 NN vs 1.45 +/- 0.03 OH (p < 0.01) vs 1.37 +/- 0.06 SH (p < 0.006)), consistent with an age-related reduction in diastolic filling. Heart rates were significantly higher in the hypertensive groups initially (63.5 NN vs 66.2 OH (p < 0.03) vs SH 67.3 (p < 0.01)) and increased in all groups over time, with the largest increase in the SH group (64.9 +/- 0.04 NN vs 67.8 +/- 1.02 OH (p < 0.0001) vs 70.9 +/- 1.6 SH (p < 0.01)). Stroke volume index changed in all groups over time, with the increase greatest in the NN group and least in the SH groups the reverse of this pattern was seen for changes in heart rate. All subjects gained weight over the 3 years of the study so that these unexpected changes in stroke volume index and heart rate could be a consequence of a weight gain related increase in the sympathetic tone, although we have no direct evidence that this is the case. Should this be so, the smaller increase in stroke volume in conjunction with the larger increase in the heart rate in the sustained hypertensive group may reflect the effects of mild blood pressure elevation in producing a reduction in left ventricular diastolic function associated with a decrease in the inotropic responsiveness of the heart to enhanced sympathetic tone. PMID- 9359996 TI - Seasonal covariation in physical fitness and blood pressure at rest and during exercise in healthy middle-aged men. AB - It has been suggested that seasonal changes in cardiovascular risk factors may explain simultaneous seasonal variations in cardiovascular diseases. Since systolic blood pressure (SBP) during an ergometer exercise test adds prognostic information beyond that of BP at rest we aimed to study whether SBP during exercise also demonstrates similar seasonal variation after adjustment for covariates. Blood pressures of 1574 apparently healthy men aged 40-59 years examined throughout two consecutive years showed a seasonal variation, with higher SBP during the period September-December compared with the rest of the year, 2.8 mmHg (p = 0.003) at rest and 4.2 mmHg (p < 0.001) during ergometer exercise at 600 kpm min-1. After adjustment for a parallel marked drop in physical fitness, these differences were no longer significant. Thus, the seasonal variation in SBP at rest and during exercise in apparently healthy middle-aged men may be explained by a parallel seasonal variation in physical fitness. A seasonal covariation in long-term cardiovascular mortality in the same study suggests that the parallel variation of independent risk factors is of clinical significance. PMID- 9359997 TI - Nocturnal fall in blood pressure in the elderly is related to presence of hypertension and not age. AB - AIMS: To determine whether the reduced nocturnal fall in blood pressure (BP) reported in elderly hypertensives is due to ageing or to the presence of hypertension. METHODS: Twenty-four hour ambulatory BP recordings of 68 normotensive elderly were compared with those of 55 elderly treated hypertensives, aged 63-88 years. Mean night-time BPs were calculated from the average of readings during sleep and mean daytime BPs from the remaining recordings. The maximum day-night BP differences were calculated. Plasma renin, aldosterone and noradrenaline were measured. RESULTS: Normotensive subjects were aged 72.0 +/- 4.7 years and treated hypertensives 73.7 +/- 4.9 years (p = 0.049). Normotensives had lower systolic BP (SBP) than hypertensives (125 +/- 12 mmHg versus 135 +/- 14 mmHg, p < 0.01). The fall in SPB at night was greater in normotensives than in hypertensives (18 +/- 9 versus 14 +/- 9 mmHg, p < 0.02). Non-dipping occurred in 24% of all subjects, with 59% of these being hypertensives. The nocturnal fall in SBP was not related to age (beta = -0.04, p < 0.62) but was inversely related to a history of hypertension (chi (2) = 5.82, p = 0.02). Serum noradrenaline was significantly related to nocturnal SBP fall (beta = 0.28, p = 0.01). CONCLUSIONS: Elderly normotensives have a greater decline in nocturnal SBP than treated elderly hypertensives. The failure of SBP to fall at night appears to be more a feature of hypertension than of ageing. Early morning noradrenaline estimations are higher in patients with a greater nocturnal blood pressure fall. PMID- 9359998 TI - Influence of indomethacin and L-NMMA on vascular tone and angiotensin II-induced vasoconstriction in the human forearm. AB - Stimulated release of vasodilator prostaglandins and nitric oxide by angiotensin II may counteract the vasoconstrictor effects of this octapeptide. We investigated the effects of inhibition of prostaglandin synthesis by indomethacin and of nitric oxide formation by NG-monomethyl-L-arginine (L-NMMA) on baseline forearm blood flow (FBF) and on angiotensin II-induced vasoconstriction in healthy subjects. For comparison, the effects of the AT1-receptor antagonist losartan on these parameters were determined. FBF was measured by venous occlusion plethysmography. Angiotensin II (0.01-10 ng/kg/min) was infused into the brachial artery, in the absence and presence of indomethacin (0.65 micrograms/kg/min; n = 8), L-NMMA (30 micrograms/kg/min; n = 5), and losartan (3 micrograms/kg/min; n = 12), respectively. Sodium nitroprusside was used to submaximally predilate the forearm vascular system. Baseline FBF remained unchanged with indomethacin and losartan, but was significantly decreased by -42 +/- 6% (mean +/- SEM) by L-NMMA. The dose-dependent angiotensin II-induced vasoconstriction was unaffected by indomethacin and L-NMMA, but was inhibited by losartan. Emax was -78 +/- 2% during control conditions, -84 +/- 3% during indomethacin (n.s.), -74 +/- 4% during L-NMMA (n.s.), and -17 +/- 6% during losartan infusion (p < 0.05). None of the interventions significantly changed the EC50 value of angiotensin II of -9.4 +/- 0.14 log M. In conclusion, in the human forearm of healthy subjects, neither endogenous angiotensin II nor cyclooxygenase dependent prostaglandin synthesis plays a role in the genesis of vascular tone, whereas endogenous nitric oxide production does. The constrictor effects of angiotensin II are counteracted by neither stimulated release of prostaglandins nor by that of nitric oxide. PMID- 9359999 TI - Heart function in patients with chronic glomerulonephritis and mildly to moderately impaired renal function. An echocardiographic study. AB - Left ventricular hypertrophy and diastolic heart dysfunction have been reported in essential hypertension and in patients with chronic renal failure, treated with haemodialysis, but a close association with blood pressure (BP) level has not been uniformly documented. Thus, other factors could be involved in the pathogenesis of cardiac dysfunction. The aims of the present echocardiographic study were to investigate cardiac morphology and function in patients with chronic glomerulonephritis with mildly to moderately impaired renal function, and to study the relation between echocardiographic findings and glomerular filtration rate (GFR), BP and age. Twenty patients with chronic glomerulonephritis and 14 healthy controls, of the same age- and sex distribution, were examined by 2D-, M-mode and pulsed-wave Doppler echocardiography. In patients, GFR was determined as plasma clearance of Cr-EDTA. The patients had significantly thicker left ventricular (LV) posterior walls in end diastole (8.7 vs 8.1 mm, p < 0.05), and a higher LV mass index (106.5 vs 93.8 g/m2, p < 0.05). Systolic functional indices, i.e. LV fractional shortening and LV ejection fraction, were statistically significantly lower in patients than in controls (p < 0.05). LV diastolic function in patients was characterized by a statistically significantly lower early peak flow velocity (E-Vmax) (0.66 compared with 0.8 m/s) and early to late peak flow velocity ratio (E/A ratio) (1.07 vs 1.41), as well as E/A ratio of time velocity indices (VTI-E/A) (1.45 vs 1.99) (p < 0.05). The right ventricular filling indices showed a tendency towards a lower E-Vmax in patients (0.55 compared with 0.62 m/s, p = 0.1). In patients, statistically significant negative correlations were found between age and mitral E/A ratio (r = -0.76, p < 0.0001), as well as LV VTI-E/A(r = -0.81, p < 0.0001). The same trend was seen for the tricuspid E/A ratio. No statistically significant correlations were found in patients between mitral or tricuspid E/A ratio and GFR, BP, LV mass or heart rate. IN CONCLUSION: in a group of patients with chronic glomerulonephritis and mildly to moderately impaired renal function, it was found by means of echocardiography that there was a higher LV mass index and decreased systolic function, when compared with healthy controls. In addition, the patients had diastolic dysfunction of primarily the left ventricle. The echocardiographic findings were not correlated to BP level or renal function. This suggests that factors other than GFR or BP per se might be involved in the pathogenesis of cardiac dysfunction, at an early stage. PMID- 9360000 TI - Blood pressure and metabolic factors in relation to chronic pain. AB - Physical pain is a major trigger for changes in many homeostatic systems of the body physiology. Our aim was to study the relationship between blood pressure, metabolism and pain perception in subjects with chronic pain symptoms. This was undertaken in a population-based study in primary health care, including subjects with widespread pain (n = 16), or localized pain (n = 15), and pain-free controls (n = 14). The main outcome measures were office and ambulatory blood pressure, glucose, insulin, lipids, and beta-endorphin. Subjects with widespread pain were more obese and showed higher levels than controls (p < 0.05) of fasting glucose (4.9 vs 4.5 mmol/l), cholesterol (6.9 vs 5.8 mmol/l) and office systolic blood pressure (133 vs 120 mmHg), while the subjects reporting localized pain had values in-between. Ambulatory blood pressure, insulin and beta-endorphin levels did not differ between the groups. In conclusion, subjects with widespread and/or intense chronic pain have higher BMI, more pronounced metabolic disturbances and higher (office) systolic blood pressure, but not ambulatory blood pressure, than subjects without chronic pain. Future epidemiological studies are needed to test whether this is compatible with increased cardiovascular risk. PMID- 9360001 TI - Low-dose reserpine/thiazide combination in first-line treatment of hypertension: efficacy and safety compared to an ACE inhibitor. AB - The concept of initiating treatment of mild-to-moderate hypertension with a low dose combination of reserpine and the thiazide clopamide in comparison to monotherapy with an ACE inhibitor was investigated. A total of 127 adult outpatients with diastolic blood pressure between 100 and 114 mmHg were randomized into this double-blind, parallel group study. After a 2-week wash-out period and a subsequent 2-week placebo run-in period, they were allocated to once daily treatment with 0.1 mg reserpine plus 5 mg clopamide (R/C), or 5 mg enalapril. If diastolic blood pressure was not normalized after 3 weeks of therapy (i.e. DBP < 90 mmHg), the dosage was doubled from week 4 to 6. The primary efficacy variables were the change from baseline in mean sitting diastolic and systolic blood pressure (DBP/SBP) after 3 weeks of therapy. Secondary variables included the change in DBP and SBP after 6 weeks of therapy, the BP normalization rates at 3 and 6 weeks and, concerning tolerability, the rates of adverse events after 6 weeks of therapy. An intent-to-treat analysis was performed. The reserpine/ clopamide and enalapril groups did not differ with regard to demographic and baseline characteristics (mean age 57 or 58 years, respectively; 63% or 56% males, respectively; mean SBP/DBP after the 2-week placebo period = 156 mmHg/104 mmHg in both groups). After 3 weeks of treatment with one capsule daily, mean SBP/DBP reduction from baseline (24 h after last medication intake) in the R/C combination group was -19.6/ -17.0 mmHg, in the enalapril group -6.1/ -9.5 mmHg (between-group comparison: 2p < 0.01 for both parameters). The normalization rates for DBP (< 90 mmHg) were 64.1% (R/C) and 28.6% (enalapril) (2p < 0.01). Adverse events that were considered possibly or definitely drug-related by the investigator were noted in 11 patients (17.2%) in the R/C group and in 9 patients (14.3%) in the enalapril group (NS). Two patients in the enalapril group discontinued the study prematurely due to adverse events (cough; skin eruption). In the treatment of mild-to-moderate hypertension, a low dose combination of reserpine and clopamide once a day is considerably more effective than, and as tolerable as, 5-10 mg of enalapril once a day. These findings suggest that treatment with a combination of different antihypertensives with different modes of action in low doses is a rational alternative to conventional monotherapy in the first-line treatment of hypertension. Besides, the "old" reserpine-diuretic regimen also in these days appears to be a rational alternative to "modern" monotherapies. PMID- 9360002 TI - Lack of effect of short-term lisinopril administration on left ventricular filling dynamics in hypertensive patients with diastolic dysfunction. AB - Arterial hypertension may be associated with altered left ventricular filling dynamics. The specific goal of this study was to evaluate whether short-term administration of the ACE inhibitor lisinopril in hypertensive patients with an altered diastolic pattern induced an improvement of left ventricular dynamics, assessed by the echocardio-Doppler technique, independently of effects on left ventricular mass. In a double-blind cross-over study 39 essential hypertensive patients with a ratio of peak early to peak atrial velocity (E/A) < 1 were randomized, after a run-in period of 2 weeks without any antihypertensive treatment, to receive lisinopril (20 mg once a day) and placebo for 4 weeks, respectively. At the end of both the run-in and the treatment periods, blood pressure and heart rate were measured and an echocardio-Doppler examination was carried out. The echocardio-Doppler evaluation was performed both at rest and at the peak of a hand-grip test (3 min at 30% of maximal strength). Left ventricular dimensions were obtained from two-dimensionally guided M-mode tracings using the criteria of the American Society of Echocardiography. Left ventricular peak filling rates and filling rate integrals were measured by a pulsed Doppler technique. Lisinopril caused a significant reduction in systolic and diastolic blood pressure at rest (-13/-9 mmHg vs baseline values, p < 0.05; -6/-4 mmHg vs placebo values, p < 0.05) and during isometric exercise (-17/-9 mmHg vs baseline period, p < 0.05; -6/-5 mmHg vs placebo, p < 0.05). Lisinopril did not induce any significant change in left ventricular structure and systolic function. All the left ventricular filling parameters considered (E velocity, A velocity, E/A ratio) both at rest and during isometric exercise did not significantly differ after lisinopril treatment when compared to those obtained in basal conditions and after placebo administration. This double-blind cross-over study demonstrates that short-term afterload reduction induced by lisinopril does not modify altered diastolic dynamics in hypertensive patients. Diastolic dysfunction of the left ventricle is a complex process influenced by a number of functional and structural factors and apparently cannot be significantly improved by short-term blood pressure reduction by antihypertensive therapy. PMID- 9360003 TI - The Hypertension Optimal Treatment (HOT) Study: 24-month data on blood pressure and tolerability. AB - The Hypertension Optimal Treatment (HOT) Study is an ongoing prospective randomized, multicentre trial conducted in 26 countries. There are two main aims of the study. The first is to evaluate the relationship between three levels of target diastolic blood pressure (< or = 90, < or = 85 or < or = 80 mmHg) and the incidence of cardiovascular morbidity and mortality in hypertensive patients. The second is to determine the effect on morbidity and mortality of a low dose, 75 mg daily, of acetylsalicylic acid (ASA, aspirin) compared with placebo. Altogether 18,790 patients have been recruited and randomized, and two-year data are now available for all patients. This is a report on the blood pressures achieved, the tolerability, and other available data after 24 months of follow-up of all patients. Special emphasis is given to the subgroup of elderly patients (> or = 65 years, n = 5988) compared with young patients (< 65 years, n = 12 802). On average, patients in the < or = 90 mmHg diastolic blood pressure target group have reached 85 mmHg, in the < or = 85 mmHg target group patients have reached 83 mmHg and in the < or = 80 mmHg target group patients have reached 81 mmHg. The percentage of those achieving target blood pressure in each target group at 24 months of follow-up is 85% in the < or = 90 mmHg target group, 75% in the < or = 85 mmHg target group and 57% in the < or = 80 mmHg target group. In the elderly subgroup (> or = 65 years of age), the percentage of patients achieving target at 24 months is higher for all target groups, namely 89% in the < or = 90 mmHg group, 80% in the 85 mmHg group and 62% in the 80 mmHg group. Antihypertensive treatment was initiated with a calcium antagonist, felodipine, at a dose of 5 mg once daily. If target blood pressure was not reached, additional antihypertensive therapy, with either an angiotensin converting enzyme (ACE) inhibitor or a beta adrenoceptor blocking agent, was given. Further dose adjustments were made in accordance with a set protocol. As a fifth, and final, step, a diuretic could be added. There have been relatively few side effects in this large, multinational study of hypertensive patients. Only ankle oedema and coughing exceed a frequency of 0.5% (ankle oedema 1.3% in young and 1.7% in elderly; coughing 0.5% in young and elderly). After two years, 84% of all patients are still taking their baseline therapy, felodipine. The 24-month data presented here indicate that it should be possible to fulfil the primary aims of the HOT Study. PMID- 9360004 TI - Sensitivity of central units in the goldfish, Carassius auratus, to transient hydrodynamic stimuli. AB - This study describes the discharges of central units in the medulla of the goldfish, Carassius auratus, to hydrodynamic stimuli received by the lateral line. We stimulated the animal with a small object moving in the water and recorded activity of 85 medullary lateral line units in response to different motion directions and to various object distances, velocities, accelerations and sizes. All but one unit increased discharge rate when the moving object passed the fish laterally. Five response types were distinguished based on temporal patterns of unit responses. Ten units were recorded which encoded motion direction by different temporal discharge patterns. In general, discharge rates decreased when object distance was increased and when object speed was decreased. When object size was decreased, discharge rates decreased systematically in one group of units, but they were comparable for all but the smallest object tested in a second group of units. Units responded about equally well whether an object was moved at a constant velocity or was accelerated when it passed the fish. The data indicate that medullary lateral line units in the goldfish can encode motion direction but are not tuned to other aspects of an object moving in the water. The functional properties of units in the medulla of goldfish are similar to those reported for medullary units in the catfish Ancistrus sp., suggesting that the central mechanisms for processing complex hydrodynamic stimuli may be quite similar in fish species that occupy habitats with different hydrodynamic conditions. PMID- 9360005 TI - Sex differences in neuropeptide staining of song-control nuclei in zebra finch brains. AB - This study examined the distribution of the neuropeptides somatostatin (SS) and calcitonin gene-related peptide (CGRP) in forebrain and midbrain song-control nuclei of male versus female brains in adult zebra finches (Poephila guttata) using immunohistochemical techniques. Vocal learning in songbirds is controlled by an interconnected, highly-localized system of brain nuclei. Male zebra finches produce learned vocalizations, and females do not. This behavioral sexual dimorphism is reflected in a substantial difference in the size of these song control nuclei: males have larger nuclei containing a greater number of neurons than do females. Interestingly, previous studies describing neurochemical aspects of the song-control system in other songbird species have not reported any obvious sex differences. However, the results of this study showed that the level of neuropeptide staining was substantially greater in telencephalic song-control nuclei of male brains compared to female brains in zebra finches. In some brain regions females lacked any apparent staining, whereas male brains were intensely labeled. In other cases the number of neurons and/or intensity of labeling were diminished in females relative to males. The telencephalic pattern of somatostatin labeling revealed a large number of SS-labeled somata in the magnocellular nucleus of the anterior neostriatum species that occupy habitats with different hydrodynamic conditions. (MAN), the high vocal center (HVC) and the robust nucleus of the archistriatum (RA) of males, whereas female song control nuclei contained many fewer or no labeled cells in these regions. Area X of the striatum appeared to contain a slightly higher level of somatostatin immunoreactivity than surrounding striatum in males, but the region corresponding to Area X in females could not be distinguished from the rest of striatum. The telencephalic pattern of CGRP staining was less extensive than that seen for SS. In male brains the magnocellular core region of lateral MAN contained many darkly labeled neurons, and RA was stained by a dense field of anterograde terminal label. Well labeled somata were also seen in medial MAN of males, but HVC was devoid of immunoreactivity. Area X in male brains contained a light field of terminal immunoreactivity. The pattern of labeling seen in males indicates that CGRP acts selectively as a neuromodulator along the efferent projection from lateral MAN to RA and Area X but not in the HVC-to-RA pathway. No telencephalic song-control nuclei in female brains contained CGRP staining. Although some diencephalic and midbrain nuclei contained well-labeled somata or fibers with either or both neuropeptides, there was little or no evidence of a sex difference in neuropeptide expression in these regions. This latter finding suggests that the greater anatomical specialization seen in cortical regions of songbirds compared to those regions in non-oscine species is accompanied by a greater neurochemical differentiation, whereas thalamic and midbrain regions may be more conserved across sex as well as species. These findings indicate that male neurons produce high levels of somatostatin and calcitonin gene-related peptide in major telencephalic vocal-control regions in zebra finches, whereas female neurons produce less or none at all. These dramatic neurochemical sex differences may be directly related to production of learned vocalizations in males, as well as to other aspects of song behavior and courtship. PMID- 9360006 TI - Effects of bombesin on behavioral thermoregulation in the bullfrog. AB - Bombesin is a member of a class of neuroactive chemicals that have potent thermoregulatory effects in ectothermic and endothermic vertebrate species. Bombesin-like peptides are found in the brains of ectothermic and endothermic vertebrates and have been implicated in the central nervous system modulation of behavioral thermoregulation. Amphibians rely on behavioral thermoregulation to maintain their body temperature within developmental stage-dependent critical limits. To investigate the influence of bombesin on behavioral thermoregulation, we examined the effects of central injections of bombesin on thermal habitat selection at different stages of bullfrog development. Tadpoles and adult male and female frogs were allowed to select a preferred temperature, within an aquatic thermal gradient, before and after receiving an intracerebroventricular injection of bombesin. In larval and adult female bullfrogs, bombesin administration caused a decrease in preferred temperature values. This effect was clearly dose-dependent in tadpoles. Bombesin effects were variable in adult males, probably due to an overriding stress response to handling exhibited by males. The bombesin-induced hypothermia was blocked by [D-Phe6, Des-Met14] bombesin (6-14), ethyl amide, a bombesin/gastrin-releasing peptide receptor antagonist. These data suggest that bombesin/gastrin-releasing peptide receptors are functional in the central nervous system of larval and adult amphibians and that receptor binding can modulate thermoregulation. They raise the question: under what natural conditions is endogenous bombesin/gastrin-releasing peptide released in the brain to activate thermoregulatory behavior? PMID- 9360007 TI - Differential accumulation and release of long-chain n-3 fatty acids from liver, muscle, and adipose tissue triacylglycerols. AB - Eicosapentaenoic acid (EPA, 20:5n-3) is less efficiently accumulated in tissue triacylglycerols (TAGs) during fish oil feeding than docosahexaneoic acid (DHA, 22:6n-3) or docosapentaenoic acid (DPA, 22:5n-3), and EPA is preferentially released from the TAG of isolated adipocytes in vitro and adipose tissue in vivo during fasting compared with DHA or DPA. It is not known if this preferential release occurs in vivo under nonfasting conditions or if it is limited to adipose tissue. Accordingly, we have carried out experiments to study the turnover of EPA, DHA, and DPA in the TAG of adipose tissue, liver, and skeletal muscle. Weanling rats were fed diets containing fish oil for 6 weeks and then switched to diets containing only corn oil as the dietary fat for 8 weeks. The fatty acid composition and mass in epididymal fat pads, omental fat, liver, and soleus muscle TAGs were determined weekly for the first 10 weeks and at weeks 12 and 14. Subsequent to the change to the corn oil diet, EPA (20:5n-3), DPA (22:5n-3), and DHA (22:6n-3), which had accumulated during fish oil feeding, were lost from the tissue TAG pools of each tissue examined. After 8 weeks on the corn oil diet, less than 10% of the accumulated EPA, DPA, and DHA remained in the liver and muscle. The loss of EPA, DPA, and DHA from epididymal fat pad was slower. In each tissue, EPA was lost more rapidly than DPA or DHA. This selective loss of EPA relative to DHA or DPA may explain the previously reported underrepresentation of EPA compared with DHA or DPA in tissue TAG. PMID- 9360008 TI - Insulin levels increase during glycemic normalization following transplantation of syngeneic islets in diabetic rats. AB - We investigated the dynamics of plasma insulin during glycemic normalization following intraportal transplantation of a marginal number of islets of Langerhans. Male Wistar Furth rats with streptozotocin-induced diabetes were hyperglycemic for 12 weeks prior to receiving either 1000 (Tx1000) or 500 (Tx500) islets. Blood samples were obtained frequently for determination of plasma glucose and insulin. All Tx1000 animals were normoglycemic within 14 days of transplantation. Among the Tx500 group, 4 of 12 animals achieved normoglycemia by 21 days post-transplant, while 7 remained hyperglycemic until the end of the study. The rate of fall of the plasma glucose was associated with the transplanted islet mass (Tx1000, 8.3 mmol.L-1.day-1; Tx500, 4.3 mmol.L-1.day-1) and was found to be more rapid than previously reported. In both groups, glycemic normalization was associated with a transient increase in circulating insulin levels. In Tx500 rats that achieved normoglycemia, insulin increased to 269 +/- 18 pmol.L-1 at 18 days, whereas in rats that remained hyperglycemic, plasma insulin was significantly less (113 +/- 6 pmol.L-1; p = 0.0004). Thereafter insulin levels were not different between groups. In summary, glycemic normalization following islet transplantation occurred after a period of sustained hyperglycemia, proceeded rapidly, and was associated with a transient increase in plasma insulin levels. Increased insulin levels may induce normoglycemia by promoting glucose uptake, thereby reducing the plasma glucose level. This initial lowering of the plasma glucose may engage a feedforward mechanism of reduced glucose desensitization, leading to improvement in beta-cell function and further reduction in plasma glucose and glucose desensitization. PMID- 9360009 TI - Use of an automated fluorescent microsphere method to measure regional blood flow in the fetal lamb. AB - We have developed a method for measuring regional blood flow by means of fluorescent microspheres in all organs and tissues of the fetal lamb, including brain, heart, lung, liver, gut, spleen, kidney, adrenal, brown fat, skin, muscle, bone, and placenta. Five different fluorescent-labeled microspheres were used: blue (B), yellow-green (Y), orange (O), red (R), and crimson (C). An automated, 96-well microplate fluorescent reader (bottom reading) was chosen for the assay because of the rapidity and high throughput that it offers. Tissue samples were digested by 4 M ethanolic KOH. The sedimentation method and dye extraction with Cellosolve acetate, as previously reported by others, were used for the sample processing. The bones were crushed and allowed to directly soak in Cellosolve acetate to extract the dye. The relationship between microsphere number and fluorescent intensity was linear over a broad range of microsphere numbers (80 20,000/mL). The coefficients of variation of within-run and between-run precision were 3.39 +/- 1.10% and 4.54 +/- 1.10%, respectively. Recovery of microspheres from tissues and blood averaged 94.3 +/- 2.5% and was not dependent on microsphere number. The spillover of the fluorescent signals into adjacent colors was 4.0 +/- 0.1% for O to Y, 8.1 +/- 0.4% for O to R, and 9.1 +/- 0.5% for R to C, and these values were constant over a wide range in concentrations of the microsphere pairs. No evidence was obtained for quenching of the emission of one fluorophore via photon absorption by another fluorophore. The measurements of regional blood flow obtained with fluorescent microspheres in three chronically instrumented fetal lambs at approximately 140 days gestation were similar to the flow estimates obtained using radioactive microspheres in four other fetal lambs at the same gestational age. The fluorescent method is thus a viable alternative to the radioactive technique for the measurement of regional blood flow to all fetal organs and tissues, particularly when an automated fluorescent microplate reader is employed to reduce analysis time. PMID- 9360010 TI - Pinaverium acts as L-type calcium channel blocker on smooth muscle of colon. AB - The effect of pinaverium was electrophysiologically characterized and compared with the established L-type calcium channel blockers diltiazem, D600, and nitrendipine on canine colonic circular smooth muscle. Effects were studied on the electrical activity of the smooth muscle cells, in particular the spontaneously occurring slow wave. In addition, effects were examined on spontaneous contraction patterns and contractile activities generated by stimulation of cholinergic nerves or directly by stimulating muscarinic receptors. Effects were also examined on excitation of NO-releasing intrinsic nerves. Pinaverium bromide affected the slow wave by selectively inhibiting the plateau potential that is associated with generation of contractile activity. Pinaverium, similar to diltiazem and D600, produced reductions in cholinergic responses as well as spontaneous contractions. The IC50 values for inhibition of cholinergic responses for pinaverium, diltiazem, and D600 were 1.0 x 10(-6), 4.1 x 10(-7), and 5.3 x 10(-7) M, respectively. The IC50 values for inhibition of spontaneous contractile activity for pinaverium, diltiazem, and D600 were 3.8 x 10(-6), 9.7 x 10(-7), and 8.0 x 10(-7) M, respectively. Increases in contractility by carbachol were abolished by pretreatment with either pinaverium or D600. In addition, neither pinaverium nor D600 had any effects on the inhibitory NO-mediated relaxations. These data provide a rationale for the use of pinaverium in the treatment of colonic motor disorders where excessive contraction has to be suppressed. PMID- 9360011 TI - The effect of stevioside on glucose metabolism in rat. AB - This study was conducted to determine the effect of stevioside (SVS) on glucose metabolism. The experiments were performed in male Wistar rats treated with SVS either by intravenous infusion or feeding. SVS infusion (150 mg/mL) was carried out in doses of 0.67, 1.00, and 1.33 mL.kg-1 body weight.h-1. The plasma glucose level significantly increased both during and after SVS infusion, whereas it was not affected by SVS feeding (13.3 mL.kg-1 body weight). The glucose turnover rate (GTR) of [14C(U)]glucose and [3(-3)H]glucose was not significantly different between control and SVS infusion animals. Percent glucose carbon recycling and glucose clearance were reduced from 28.7 +/- 1.3 to 23.0 +/- 1.6% (p < 0.05) and from 6.46 +/- 0.34 to 4.99 +/- 0.20 mL.min-1.kg-1 body weight (p < 0.01), respectively. The plasma insulin level did not change, whereas the plasma glucose level significantly increased from 120.3 +/- 5.9 to 176.8 +/- 10.8 mg% (p < 0.01) during SVS infusion. Animals pretreated with angiotensin II and arginine vasopressin showed no significant effect, while animals pretreated with prazosin had an attenuated hyperglycemic effect of SVS infusion. Pretreatment with indomethacin or N omega-nitro-L-arginine methyl ester (L-NAME) alleviated the plasma glucose level during the second period of SVS infusion. Pretreatment with the combination infusion of indomethacin and L-NAME reduced the plasma glucose level from 117.0 +/- 1.8 to 109.0 +/- 1.7 mg% (p < 0.001), and normalized the plasma glucose level in the second period of SVS infusion. Insulin infusion inhibited the hyperglycemic effect of SVS infusion. The present results show that the elevation of the plasma glucose level during SVS infusion is not due to the reduction of the insulin level. It is probably the effect of SVS on glucose transport across the cell. Insulin response to a high plasma glucose level is suppressed during SVS infusion. Several interactions among norepinephrine, prostaglandin, and nitric oxide are involved in modulating the hyperglycemia during SVS infusion. PMID- 9360012 TI - Atypical antidepressants inhibit depolarization-induced calcium uptake in rat hippocampus synaptosomes. AB - The effect of the atypical antidepressants mianserin, iprindole, and fluoxetine on synaptosomal calcium uptake was tested under conditions where a selective action on voltage-dependent calcium channels can be documented. Synaptosomes from rat hippocampus were incubated with 45calcium either in choline-rich medium or in depolarizing (60 mM K+) choline-rich medium, and drug effects on calcium uptake in these two conditions, as well as on the net depolarization-induced calcium uptake, were studied in the range of concentrations 0.6-200 microM. A concentration-dependent marked inhibition of uptake in depolarizing choline medium was observed for the three antidepressants, whereas only a minor degree of inhibition of uptake in resting choline medium was present at the highest drug concentration; as a result, the concentration-effect relationships exhibited a strong concentration-dependent inhibition of net depolarization-induced calcium uptake. The IC50 values, calculated by interpolation of the last three or four points of the concentration-effect relationships, were 27, 39, and 68 microM for fluoxetine, iprindole, and mianserin, respectively. Significant degrees of calcium channel inhibition are not expected at brain concentrations of mianserin and iprindole that are likely to be encountered during clinical use; however, the fluoxetine concentration-effect relationship established in the present study, coupled with the published ratio of 20:1 for brain:plasma concentrations of fluoxetine-norfluoxetine in humans, suggests that brain calcium channel function could be appreciably reduced in some patients treated with this atypical antidepressant. PMID- 9360013 TI - Contrast media induced changes in tubular electrophysiology and glomerular filtration rate in the mouse kidney. AB - The isolated perfused mouse proximal tubule was used to examine electrophysiologic effects of diatrizoate and ioversol. Luminal or basolateral application of diatrizoate resulted in a dose-dependent, reversible hyperpolarization of the proximal tubule cell basolateral membrane potential (VB), which could be abolished by the addition of 10 microM probenecid. While there was a modest reduction in intracellular ATP following a 60-min exposure to diatrizoate, there was no deterioration of VB after 90 min of diatrizoate exposure, even following a 20-min hypoxic insult. Ioversol did not elicit an electrical response. Neither diatrizoate nor ioversol significantly affected transepithelial potential (VT) in the isolated perfused medullary thick ascending limb. In vivo studies showed that only the ionic contrast agent diatrizoate significantly reduced glomerular filtration rate, by 70%. The observed acute contrast media induced reduction in glomerular filtration rate does not appear to depend on direct renal tubular cytotoxicity. PMID- 9360014 TI - Effects of a quaternary pyridinium metabolite of haloperidol (HP+) on the viability and catecholamine levels of cultured PC12 cells. AB - Haloperidol has been found to be metabolized to a pyridinium ion (HP+; 4-(4 chlorophenyl)-1-[4-(4-fluorophenyl)-4-oxobutyl]-pyridinium). HP+ is structurally similar to the toxic metabolite of the dopaminergic neurotoxin N-methyl-4-phenyl 1,2,3,6-tetrahydropyridine (MPTP), N-methyl-4-phenylpyridinium (MPP+). HP+ is toxic towards dopaminergic neurons and was proposed to be associated with some of the extrapyramidal side effects of haloperidol. We therefore investigated the neurotoxicity of HP+ towards cultured PC12 cells. At high concentrations, HP+ reduced the viability of PC12 cells as measured by trypan blue exclusion and the MTT method. However, HP+ decreased intracellular dopamine (DA), 3,4 dihydroxyphenylacetic acid (DOPAC), and dihydroxyphenylalanine (DOPA) levels at lower concentrations than those required to compromise cell viability. The immunoreactivity of tyrosine hydroxylase was not affected by the treatment with HP+. It was subsequently demonstrated that HP+ can release [3H]DA preloaded in rat striatum slices. Thus, it is proposed that HP+ decreases dopamine content in PC12 cells through actively releasing amines from the cells and (or) blocking the reuptake of the released amines. PMID- 9360015 TI - Differential in vivo and in vitro bronchorelaxant activities of CP-80,633, a selective phosphodiesterase 4 inhibitor. AB - CP-80,633, a selective phosphodiesterase (PDE) 4 inhibitor, potently reverses histamine bronchoconstriction in anesthetized guinea pigs (ED50 10 micrograms/kg) but only weakly relaxes histamine-constricted guinea pig trachea (EC50 137 microM). Using CP-80,633 as a prototype PDE4 inhibitor, we evaluated the hypothesis that bronchodilation induced by PDE4 inhibitors is not mediated by direct relaxation of airway smooth muscle. In anesthetized guinea pigs, a bronchodilatory dose of CP-80,633 did not increase plasma catecholamines, nor did propranolol pretreatment significantly alter the ability of CP-80,633 to reverse histamine bronchoconstriction. In an isolated organ system, the activity of bronchorelaxants may be attenuated by the lack of endogenous activators of adenylyl cyclase or by decreased levels of intracellular cyclic nucleotides. Pretreatment with the beta-adrenoceptor agonist, salbutamol, or the PDE3 inhibitor imazodan did not potentiate the bronchorelaxant ability of CP-80,633. Milrinone pretreatment increased the potency of CP-80,633 to relax carbachol constricted tracheal rings, but only at concentrations where nonspecific effects have been reported. By comparing the bronchorelaxant abilities of PDE inhibitors in tracheal rings with or without epithelium, we determined that the epithelium did not serve as a barrier to drug penetration. In conclusion, CP-80,633 is a potent bronchodilator in vivo, whose activity is neither mediated by direct airway smooth muscle relaxation nor dependent upon endogenous catecholamines. PMID- 9360016 TI - Dietary lipids influence the activity of delta 5-desaturase and phospholipid fatty acids in rat enterocyte microsomal membranes. AB - Previous studies have shown that isocaloric modifications in the type of lipids in the diet alter the nutrient uptake and lipid composition of the intestinal brush border membrane. In this study adult rats were fed for 2 weeks isocaloric semisynthetic diets with triglycerides enriched with either saturated (S) or polyunsaturated (P) fatty acids. Enterocyte microsomal membranes (EMMs) were isolated from along the jejunal villus. The activity of delta 5-desaturase was higher in the upper than in the lower portions of the villus, and was greater in P than in S. The activity of delta 9- and delta 6-desaturases did not vary along the villus or with changes in dietary S or P. The two predominant EMM phospholipids were phosphatidylcholine and phosphatidylethanolamine, and these did not vary along the villus or with changes in diet. The major EMM fatty acids in phosphatidylcholine and phosphatidylethanolamine were 16:0, 18:0, 18:2 omega 6, and 20:4 omega 6; none of the individual fatty acids varied along the villus or with diet, although minor changes in fatty acid classes were observed. Thus, alterations in dietary lipids modify the activity of delta 5-desaturase in the EMMs collected from the upper portion of the villus, but this does not result in the expected changes in fatty acids in the EMM phospholipids. PMID- 9360017 TI - Free magnesium concentration in isolated rabbit hearts subjected to high dose isoproterenol infusion: a 31P NMR study. AB - The hypothesis of magnesium deficiency in isoproterenol (ISO) induced myocardial injury has been investigated by 31P nuclear magnetic resonance spectroscopy. High energy phosphate concentrations, pHi, and intracellular free magnesium concentration ([Mg2+]i) were measured in isolated rabbit hearts perfused at constant flow and subjected to 10(-6)M isoproterenol during 30 min. Recent calibrations were used for [Mg2+]i measurements, and uncertainties on [Mg2+]i estimated values were calculated. During isoproterenol infusion, pHi, [PCr], and [ATP] decreased, while [P(i)] increased. When it was stopped, [PCr] completely repleted, whereas only a partial restoration was observed for pHi and [P(i)]. A rise of end-diastolic pressure and perfusion pressure expressed a contracture, concomitant with a lack of [ATP] recovery, which remained at 59 +/- 13% of the rest value. These results establish that 10(-6) M isoproterenol caused severe myocardial injury. [Mg2+]i increased from 0.70 mM at rest to 0.88 mM at the end of the isoproterenol period. Considering the estimated uncertainties on the [Mg2+]i values, this increase was not significant. After isoproterenol infusion, [Mg2+]i progressively decreased to reach 0.72 mM at 45 min recovery. It is concluded that isoproterenol myocardial toxicity may not be related to [Mg2+]i deficiency. PMID- 9360018 TI - Modulation by beta-naphthoflavone of ovarian hormone dependent responses in rat uterus and liver in vivo. AB - The potential of an aryl hydrocarbon receptor (AhR) agonist, beta-naphthoflavone (beta-NF), to modulate ovarian hormone responses in the uterus and liver of 50 day-old Sprague-Dawley rats was examined. Treatment with beta-NF at 40 mg/kg of body weight consisted of 3 or 9 intraperitoneal injections in corn oil administered to ovariectomized (OVX) and sham-treated (SH) rats on day 5 through 7 or 1 through 9 after surgery performed on day 42 or 40 of age, respectively. Treatment of SH rats with either dose regimen of beta-NF effected a decrease (approximately 80%) in the uterine peroxidase activity, which was similar to that effected by ovariectomy (> 93%). By contrast, treatment of rats with alpha naphthoflavone, an AhR antagonist, did not decrease the peroxidase activity. After the 9-dose treatment with beta-NF, decreases (approximately 70%) in hepatic estrogen receptor (ER) levels in both SH and OVX rats exceeded those effected by ovariectomy (30%). However, treatment with beta-NF partially prevented the ovariectomy-effected increase (approximately 1.5-fold) in body weight gain, decrease (approximately 67%) in uterine weight, and increase (3-fold) in uterine ER level. In both SH and OVX rats, treatment with beta-NF increased (1.7-fold) uterine progesterone receptor (PR) levels, which were unaffected by ovariectomy. Thus, the results suggest that the effect to of treatment with beta-NF is both mimicking and counteracting the effects of estrogen. Since beta-NF itself or upon conversion to metabolites by liver microsomes was shown herein not to be a ligand for uterine ER and PR, the aforementioned effects of beta-NF resembled those of certain halogenated polycyclic hydrocarbons, and thus may be mediated via AhR. PMID- 9360019 TI - Beta 2-agonist regulation of cell volume in fetal distal lung epithelium by cAMP independent Ca2+ release from intracellular stores. AB - The effects of beta 2-adrenoceptor agonist (beta 2 agonist) and cAMP on cytosolic Ca2+ concentration ([Ca2+]c) and cell volume were studied in fetal distal lung epithelial cells. Both terbutaline (a specific beta 2 agonist, 10 microM) and dibutyryl cAMP (DBcAMP, 1 mM) increased [Ca2+]c in the presence of extracellular Ca2+. Even in the absence of extracellular Ca2+, the terbutaline-induced increase in [Ca2+]c was still observed, although the increase was transient. However, DBcAMP caused no significant change in [Ca2+]c. In the presence of 1 mM extracellular Ca2+, terbutaline and DBcAMP induced quinine (a blocker of K+ channel) sensitive cell shrinkage. However, in a Ca2(+)-free solution, terbutaline induced rapid cell shrinkage, followed by benzamil (a specific blocker of Na+ channel, an analogue of amiloride) sensitive transient cell swelling. In a Ca2(+)-free solution, DBcAMP induced benzamil-sensitive transient cell swelling without cell shrinkage. Taken together, our observations indicate that the beta 2 agonist induced an elevation of [Ca2+]c by increasing both a Ca2+ influx from the extracellular space and a Ca2+ release from intracellular Ca2+ stores, whereas DBcAMP only stimulated Ca2+ influx from the extracellular space. Furthermore, it is suggested that terbutaline and DBcAMP activated benzamil sensitive channels independently of an increase in [Ca2+]c. PMID- 9360020 TI - The soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin 1-one (ODQ) inhibits relaxation of rabbit aortic rings induced by carbon monoxide, nitric oxide, and glyceryl trinitrate. AB - Carbon monoxide (CO), a vasodilator, has been implicated as an activator of soluble guanylyl cyclase (sGC) to effect smooth muscle relaxation; however, this idea has not received universal support. The purpose of this study was to examine the effects of the sGC inhibitor 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one (ODQ) on relaxation of rabbit aortic rings (RARs) induced by CO. Administration of 10 microM ODQ completely abolished relaxation of RARs by CO (30 microM), whereas only a partial attenuation of NO-induced relaxation was achieved by the same concentration of ODQ. The results of this study suggest that CO-mediated relaxation of RARs is mediated by sGC and indicate that ODQ may serve as a useful tool in the investigation of the actions of CO. Furthermore, these observations support the idea that ODQ is less potent in inhibiting relaxations by NO, thereby implicating a component of NO-induced relaxation that is independent of sGC/cGMP. PMID- 9360021 TI - Rapid phase resetting of a mammalian circadian rhythm by brief light pulses. AB - The phase-shift (delta phi) responses of the circadian rhythm in the field mouse Mus booduga to brief light pulses (LPs) of 15 minutes duration and 1000 lux intensity were measured in 90 experiments. In each experiment, a resetting light pulse LP1 was administered at CT14 (CT, circadian time), and a scanning light pulse LP2 was then variously administered in separate experiments at CT16, CT20, and CT22 in the same and in the next circadian cycle. The delta phi obtained in all these two-pulse experiments did not differ significantly from theoretical values computed on the assumption that LP1 reset the phase response curve (PRC) rapidly. In each case, the steady-state delta phi observed after LP1 and LP2 differed significantly from the delta phi obtained at the same CT in determination of the single-pulse PRC (control) and also differed significantly from the values on the assumption of no delta phi in the PRC following LP1. These results indicate that the circadian pacemaker of M. booduga, as measured by its PRC, is substantially reset within 2h after a light pulse at CT14. PMID- 9360022 TI - Transient fluctuation of serum melatonin rhythm is suppressed centrally by vitamin B12. AB - Vitamin B12 has been reported to improve sleep-wake rhythm disorders. Although the mechanism is still unclear, a change in the sensitivity of the circadian clock system to photic input is thought to be a possible mechanism of the effect. In this study, the effect of the vitamin B12 on the circadian aspect of the electroretinogram (ERG) and serum melatonin level was analyzed in rats. Vitamin B12, alpha-(5,6-dimethylbenzimidazolyl)-co-methyl-cobamide was daily administrated subcutaneously for 8 weeks to adult male Wister rats in the experimental group, and saline was given to the control group. The ERGs were recorded under dark adaptation during the night and day, and under light adaptation (0.1 lux) during the night. Blood was drawn before and after ERG recording. The amplitudes of the a-wave, b-wave, and trough-to-peak of both waves and latencies of ERG were analyzed following various exposures to stimuli of light intensity. These parameters in the group treated with vitamin B12 showed similar characteristics to the control group, and no significant difference was observed between the two groups. The melatonin levels of both groups before the measurement of ERG were similar under each measurement condition. The elevated serum melatonin concentration in the control group under dark adaptation at night was suppressed after the series of 10-msec light stimuli used for measurement of ERG. However, this suppressing effect of light pulses on melatonin level was significantly inhibited in the group treated with vitamin B12. Under light adaptation during the night and under dark adaptation during the day, melatonin levels after the measurement of ERG were not different between the groups. From these results, it is suggested that vitamin B12 if effective in suppressing melatonin rhythm disturbances introduced by transient light stimulation, and it affects the site more central than the retinal level. PMID- 9360023 TI - Analysis of telemetric time series data for periodic components using DQ-FIT. AB - DQ-FIT and CV-SORT have been developed to facilitate the automatic analysis of data sampled by radiotelemetry, but they can also be used with other data sampled in chronobiological settings. After import of data, DQ-FIT performs conventional linear, as well as rhythm analysis according to user-defined specifications. Linear analysis includes calculation of mean values, load values (percentage of values above a defined limit), highest and lowest readings, and areas under the (parameter-time) curve (AUC). All of these parameters are calculated for the total sampling interval and for user-defined day and night periods. Rhythm analysis is performed by fitting of partial Fourier series with up to six harmonics. The contribution of each harmonic to the overall variation of data is tested statistically; only those components are included in the best-fit function that contribute significantly. Parameters calculated in DQ-FIT's rhythm analysis include mesor, amplitudes, and acrophases of all rhythmic components; significance and percentage rhythm of the combined best fit; maximum and minimum of the fitted curve and times of their occurrence. In addition, DQ-FIT uses the first derivative of the fitted curve (i.e., its slope) to determine the time and extent of maximal increases and decreases within the total sampling interval or user-defined intervals of interest, such as the times of lights on or off. CV SORT can be used to create tables or graphs from groups of data sets analyzed by DQ-FIT. Graphs are created in CV-SORT by calculation of group mean profiles from individual best-fit curves rather than their curve parameters. This approach allows the user to combine data sets that differ in the number and/or period length of harmonics included. In conclusion, DQ-FIT and CV-SORT can be helpful in the analysis of time-dependent data sampled by telemetry or other monitoring systems. The software can be obtained on request by every interested researcher. PMID- 9360024 TI - Circadian reactivity rhythm of rat gastric mucosa to restraint-cold stress and indomethacin: temporal variation in the protective effect of iloprost. AB - In this study, the time-dependent ulcerogenic effects of restraint-cold stress and indomethacin on the gastric mucosa and the temporal variation in the protective effect of iloprost, a synthetic stable analog of prostacyclin, were investigated in rats synchronized to 12h light and 12h darkness, lights on at 08:00. The severity of gastric ulceration produced by either stress or indomethacin showed marked circadian variation; it was greatest at 11 HALO (hours after lights on) for restraint-cold stress and at 23 HALO for indomethacin. The severity of the induced ulcerogenesis was least at 7 HALO for both stimuli. The protective effect of iloprost against restraint-cold stress was most prominent at 15 HALO and 19 HALO with an approximately 80% protection score. On the other hand, pretreatment with iloprost reduced the indomethacin-induced mucosal injury only at 23 HALO. The circadian variation in the effect of iloprost and in the rhythmic modalities of these two experimental ulcer models are indicative of differences in their underlying mechanisms. In experimental models of ulceration, the circadian time of application of the ulcerogenic stimulus must be considered as an important experimental factor. Moreover, the protective effectiveness of antiulcer drugs can express time-dependent differences and must also be taken into account in investigative research. PMID- 9360025 TI - Human time perception in temporal isolation: effects of illumination intensity. AB - Living in isolation from time cues under relatively high and low light intensities for a total (on average) of 24 days, 18 subjects estimated the passage of time by "producing" short (10 to 120 seconds) and long (1h) intervals throughout the experiments. The 1h productions were independent of light intensity and highly positively correlated with the duration of wake times. The short-interval productions were markedly increased under high light intensity. In a subsample of 6 subjects, the interaction between effects of body temperature and light condition on 10-second production was analyzed. Productions were negatively correlated with body temperature. In both dim and bright light, productions decreased by a factor of 0.7 per degree C. In bright light, production was increased by a factor of 1.2 relative to dim light. This effect was not mediated by body temperature, which itself was on average slightly increased in bright light. Since subjective time is slowed by bright light, objective time seems to pass faster in bright light. PMID- 9360026 TI - Heart rate variability during 24 hours in asthmatic children. AB - The autonomic circadian rhythm plays an important role in asthma. In recent years it has become possible to evaluate autonomic nervous function (ANF) using analysis of heart rate variability (HRV). We analyzed the HRV in the 24h period following the state without an asthma attack in order to study the relationship between asthma and ANF. The HRV was analyzed in 94 asthmatic children (ages 5-15 years). These subjects were divided into groups according to the severity of their asthma. After recording a 24h ambulatory electrocardiograph (AECG), the HRV was analyzed by a computer. Evaluation of the HRV was carried out using time domain and frequency-domain analyses. The ANF of asthma subjects was decreased in comparison to the normal group. The severity of asthma had a significant effect on the %RR50 (the proportion of cycles during which the difference is > 50 ms), the SD (standard deviation; mean of standard deviation of all normal RR intervals for all 5-minute periods), the low-frequency (LF) band (0.04 to 0.15 Hz), and the high-frequency (HF) band (0.15 to 0.4 Hz) (%RR50: F = 4.31, p = 0.01; SD: F = 3.48, p = 0.03; LF: F = 3.67, p = 0.02; HF: F = 3.41, p = 0.03). These values were lowest in the severe asthma group. With regard to the therapy grouping, the index that exhibited a significant difference was the NNA (mean of normal-to normal RR intervals over 24h) (F = 4.43, p = 0.01). In conclusion, even in the normal condition in which the patient is free of an asthma attack, the ANF of asthma sufferers differs from that of normal children. It is possible that the different ANF of asthma sufferers is related to the severity of the asthma. PMID- 9360027 TI - Effects of two types of clothing on the day-night variation of core temperature and salivary immunoglobulin A. AB - Circadian variations in core temperature, skin temperatures, heart rate, and salivary immunoglobulin A (IgA) were compared in subjects wearing two different types of clothing that covered, or left uncovered, their extremities. The experiments were carried out on six female subjects at an ambient temperature of 24 +/- 0.5 degrees C and relative humidity of 50 +/- 5%. One type of clothing consisted of long-sleeved shirts, full-length trousers, and socks (Type L: 1042 g, 1.048 clo); the other was half-sleeved shirts and knee-length trousers (Type H: 747 g, 0.744 clo). The main results were as follows: (i) The level of rectal temperature during night sleep was significantly lower with Type H than Type L clothing, and cosinor analysis indicated a significantly higher circadian amplitude with Type H clothing. (ii) Skin temperatures in the lower extremities increased significantly more on retiring to sleep with Type H than Type L clothing. (iii) Heart rate was significantly lower with Type H than Type L clothing during the sleep period. (iv) The day-night variation of salivary IgA showed a pattern that was the inverse of that of rectal temperature (i.e., low in the daytime and high in the nighttime), and the concentration of salivary IgA was significantly higher with Type H than Type L clothing at 02:30. (v) Subjectively, the self-assessed sleep quality was better with Type H clothing. These results suggest that clothing that leaves the extremities uncovered might be regarded as favorable at the moderate temperature since it induces good sleep and activates the immune response. PMID- 9360028 TI - Influence of aspirin usage on blood pressure: dose and administration-time dependencies. AB - This study investigates the possible effects of acetylsalicylic acid (ASA; aspirin) on systolic (S) and diastolic (D) blood pressure (BP) in healthy and mildly hypertensive subjects receiving ASA at different times according to their rest-activity cycle. A double-blind, randomized, controlled trial was conducted in 73 healthy young adult volunteers and 18 previously untreated subjects with mild hypertension. The BP of each subject was automatically monitored every 30 minutes for 48h before the trial and at the end of a one-week course of placebo and a one-week course of ASA. Healthy volunteers were randomly assigned to one of six groups, defined according to the dose of ASA (either 500 mg/day, the usual commercial dose; or 100 mg/day) and timing of ASA and placebo (within 2h after awakening, Time 1; 7h to 9h after awakening, Time 2; or within 2h of bedtime, Time 3). Subjects with mild hypertension received the low dose of 100 mg/day ASA, as well as one week of placebo, and were randomly assigned to one of the same three groups defined above according to the time of treatment. A small (approximately 2 mmHg in the 24h mean of SBP), but statistically significant, BP reduction was found when 500 mg/day ASA was given to healthy volunteers at Time 2. With 100 mg/day, the effect of ASA in healthy subjects was comparable to the BP reduction found with the higher dose for Time 2; there was again no effect on BP at Time 1, but we found a statistically significant effect at Time 3 (2.3 mmHg reduction in the 24h mean of SBP), larger than for Time 2. For hypertensive patients, the BP reduction was again statistically significant for Time 2 and, to a greater extent, for Time 3 (approximately 4.5 mmHg for both SBP and DBP); all patients in these two groups showed a BP reduction after one week of ASA. The effect was about three times as large as the BP reduction obtained in healthy subjects treated with 100 mg/day ASA. Results indicate a statistically significant time- and dose-dependent effect of ASA on BP. In any meta-analysis of ASA effects, inquiries about the time when subjects took the drug are indicated and may account for discrepancies in the literature. Moreover, the influence of ASA on BP demonstrated here indicates the need to identify and control for ASA effects in patients using ASA before and during their participation in antihypertension medication trials. PMID- 9360029 TI - Seasonal rhythm of red pigment concentrating hormone in the crayfish. AB - The content of red pigment concentrating hormone (RPCH) in the eye-stalk of the crayfish Procambarus clarkii varies seasonally, with maximum values during the summer months and the lowest values in winter. The responsiveness of tegumentary chromatophores to synthetic RPCH varies concurrently. PMID- 9360030 TI - A review of outcome indicators in the treatment of chronic limb oedema. AB - OBJECTIVES: To provide an overview of physical and psychological outcome indicators which have been used to evaluate conservative treatments for chronic oedema. METHODS OF FINDING PAPERS: Papers were located via the MedLine, CINAHL and GEARS databases, and the British Lymphology Interest Group Key References lists. ISSUES REVIEWED: The literature reveals that only a small amount of work has addressed conceptual issues in outcome evaluation. Above all, outcome indicators have been adopted in clinical practice in a haphazard manner, with little discussion regarding the purpose of outcome assessment/measurement and little agreement on the most appropriate assessment/measurement techniques. RESULTS: Eleven outcome indicators appear in the literature, each of which is discussed in terms of instrumentation and application in clinical practice. Practitioners have focused on objective measures, with change in limb volume the outcome measure most commonly used. CONCLUSION: It is concluded that more rigour is needed in many aspects of outcome evaluation. Practitioners and researchers in this field should become more questioning of existing evaluation practices, and should explore the many potential outcome indicators, such as limb movement and limb function, which have to date been neglected. PMID- 9360031 TI - A one year follow-up study on the effects of acupuncture in the treatment of stroke patients in the subacute stage: a randomized, controlled study. AB - OBJECTIVE: We recently reported that acupuncture treatment of stroke patients in the subacute stage gave additive therapeutic benefit. The purpose of the present study was to determine, approximately one year after discharge from the rehabilitation hospital, whether the group differences still remained. DESIGN: The patients were randomized into two groups: one acupuncture group and one control group, considering gender and side of hemispheral localization of lesion. With regard to the main parameters the groups were comparable at baseline. SETTING: Initially, 45 stroke patients admitted to Sunnaas Rehabilitation Hospital were included in the study: median 40 days post stroke. SUBJECTS: Forty one of the patients were available one year after the treatment period: 21 patients in the acupuncture group and 20 controls. INTERVENTION: All subjects received an individually adapted, multidisciplinary rehabilitation programme. The acupuncture group received additional treatment with classical acupuncture for 30 min three to four times weekly for six weeks. MAIN OUTCOME MEASURES: The patients were evaluated at inclusion, after six weeks and approximately 12 months after discharge from the rehabilitation hospital. The Motor Assessment Scale (MAS) for stroke patients, Sunnaas Index of Activity of Daily Living (ADL) and Nottingham Health Profile (NHP) were used. In addition, the social situations of the patients were recorded at one year follow-up. RESULTS: The results show that the acupuncture group improved significantly more than the controls, both during the treatment period of six weeks, and even more during the following year, both according to MAS, ADL, NHP and the social situation. CONCLUSION: Although the mechanism of the effects is debatable, there seems to be a positive long-term effect of acupuncture given in the subacute stage post stroke. PMID- 9360032 TI - The effects of common peroneal stimulation on the effort and speed of walking: a randomized controlled trial with chronic hemiplegic patients. AB - OBJECTIVE: To measure the effect of the Odstock Dropped Foot Stimulator (ODFS), a common peroneal stimulator, on the effort and speed of walking. DESIGN: A randomized controlled trial. SUBJECTS: Hemiplegic patients who had suffered a single stroke at least six months prior to the start of the trial whose walking was impaired by a drop-foot. INTERVENTIONS: The treatment, functional electrical stimulation (FES) group, used the stimulator and received a course of physiotherapy; the control group received physiotherapy alone. MAIN OUTCOME MEASURES: Changes in walking speed measured over 10 m and the effort of walking measured by physiological cost index (PCI). RESULTS: Thirty-two subjects completed the trial, 16 in the FES group and 16 in the control group. Mean increase in walking speed between the beginning and end of the trial was 20.5% in the FES group (when the stimulator was used), and 5.2% in the control group. Improvement was also measured in PCI with a reduction of 24.9% in the FES group (when the stimulator was used) and 1% in the control group. No improvement in these parameters was measured in the FES group when the stimulator was not used. CONCLUSION: Walking was statistically significantly improved when the ODFS was worn but no 'carry-over' was measured. Physiotherapy alone, in this group of subjects with established stroke, did not improve walking. PMID- 9360033 TI - Pelvic floor rehabilitation is effective in patients with multiple sclerosis. AB - OBJECTIVE: To determine the effect of pelvic floor muscle exercises combined with electrical stimulation of pelvic floor on lower urinary tract dysfunction in multiple sclerosis (MS) patients with near normal (< 100 ml) postvoid residual volumes. DESIGN: Open, controlled, randomized study in two parallel groups. SETTING: Rehabilitation centre for MS patients. SUBJECTS: Fifty women and 30 men with definite MS and current symptoms of lower urinary tract dysfunction. OUTCOME: The muscle activity of the pelvic floor muscles was tested using surface EMG. Subjective urinary symptoms were assessed using a questionnaire. INTERVENTIONS: Pelvic floor muscles were stimulated using electrical stimulation at six sessions. During and after the final session the patients were taught to exercise their pelvic floor muscles and advised to continue these exercises regularly for at least six months. The control group was not treated. RESULTS: The maximal contraction power and endurance of the pelvic floor muscles increased after six sessions of electrical stimulation with interferential currents. Symptoms of urinary urgency, frequency and incontinence were significantly less frequent in the treated group than in the untreated subjects. Male patients appeared to respond better to the treatment than female patients. Compliance with the pelvic floor exercises was over 60% at the end of a follow-up for six months. Most drop-outs were due to the disappearance of urinary tract symptoms or to severe relapses in MS. CONCLUSIONS: The present study indicates that pelvic floor muscle exercises combined with electrical stimulation of the pelvic floor constitute an effective treatment for lower urinary tract dysfunction at least in male patients with MS. PMID- 9360034 TI - Improvement in gait parameters following late intervention in traumatic brain injury: a long-term follow-up report of a single case. AB - OBJECTIVE: To evaluate the effect of using an optimally adjusted fixed ankle foot orthosis to control knee pain and promote improvement in gait parameters in a subject with hemiplegia following a traumatic brain injury 11 years previously. DESIGN: This is the report of a single case, using gait laboratory facilities to monitor force alignment relative to the knee and single leg balance time with the subject barefoot. SUBJECT: A 35-year-old woman with a right hemiplegia seen 11 years after onset. INTERVENTION: A polypropylene fixed ankle foot orthosis was supplied to the hemiplegic limb and shoe modifications were made to optimize the position of the ground reaction force relative to the knee during stance phase of gait. This orthosis was used on a daily basis for one year. RESULTS: Knee pain was controlled after three months use of the orthosis. Graphical results of force alignment during stance phase of gait are presented for initial assessment and at one and four years postorthotic supply. A large knee-extending effect was noted on the hemiplegic limb at initial assessment and this was reduced by 67% of its initial value at one year. A compensatory early heel lift was initially noted on the opposite limb and this was reduced by 42% of the initial height at one year. These results were maintained at four years. Right leg standing balance was not initially possible but was recorded as 5 s duration at three months and this was maintained at one and at four years. CONCLUSIONS: The use of an optimally adjusted ankle foot orthosis was effective in controlling knee pain and improving barefoot gait parameters with maintenance of the improvement after use of the orthosis was discontinued. Further research is required to fully establish the potential of this approach in subjects with traumatic brain injury. PMID- 9360035 TI - Community integration of wheelchair-bound athletes: a comparison before and after onset of disability. AB - OBJECTIVES: (1) To assess to what extent wheelchair-bound athletes living independently in the community were able to return to their premorbid level of functioning in the community; (2) to investigate how they value their current way of functioning in comparison to that before disability; and (3) to examine the factors that hamper their return to their premorbid life in four domains. METHODS: Forty-four wheelchair-bound athletes participated in this study. Data were collected by means of a self-administered semi-structured questionnaire which was divided into four domains: vocational status, leisure time activities, social functioning and relationship with partner. RESULTS: Return to premorbid level of functioning in the community in the long term was reasonably well achieved for the domains 'leisure activities', 'social contacts' and 'relationship with partners', but not for 'vocational situation'. Between 60% and 80% of the participants reported satisfaction with their current level of functioning for all domains. However, about 50% of the respondents reported that they were currently less satisfied with their functioning on the domains 'vocational situation' and 'leisure activities', compared to before the onset of disability. Factors limiting integration were principally access to buildings and physical health problems (pain and fatigue). CONCLUSION: It appeared that wheelchair-bound athletes were able to live a life on a level comparable to that before onset of disability for three of the four domains. It was emphasized that pain treatment in late rehabilitation and improving access for the disabled can contribute to the further integration of wheelchair-bound people into the community. PMID- 9360036 TI - Outcome after stroke rehabilitation in Hong Kong. AB - OBJECTIVE: To determine the outcome of patients discharged to the community after stroke rehabilitation. METHODS: One hundred and eighty-five consecutive patients discharged after stroke rehabilitation were enrolled for follow-up 12 months after discharge from a hospital in Hong Kong. A telephone interview to determine disability and place of residence was conducted. Disability was assessed by the Barthel Index and ratings of activities of daily living and mobility on a 4-point scale. RESULTS: One hundred and thirty-one patients or their carers were contacted (70.1%). This comprised 19 patients (10.3%) who died and 112 patients or their carers (60.5%) who were interviewed. Fifty-four patients (29.2%) were lost to follow-up. Comparison of the patients contacted and those lost to follow up did not detect membership bias. Median Barthel Index of the surviving patients who were contacted rose from 90.0 (interquartile range 78.75-100.0) at discharge to 100.0 (interquartile range 85.0-100.0) at 12 months. Ratings of activities of daily living and mobility were maintained, with significant improvement in toileting. After rehabilitation 77.3% of the patients were discharged home and there was no significant change in residence at 12 months. Elderly patients (> or = 70 years old) had higher rates of institutionalization after hospital discharge and more disability although they achieved similar gains in Barthel Index and had similar lengths of hospital stay compared to younger patients. CONCLUSIONS: These results suggest that stroke patients were able to maintain their gains achieved during inpatient rehabilitation up to one year after discharge from hospital. PMID- 9360037 TI - Evaluation of a shortened version of the Abbreviated Mental Test in a series of elderly patients. AB - OBJECTIVE: To determine whether a shortened version of the Abbreviated Mental Test is as effective as the Abbreviated Mental Test (AMT) itself in assessing cognition in elderly patients. DESIGN: A shortened four-item version of the Abbreviated Mental Test (AMT4) was constructed using the following items: (1) Age, (2) Date of birth, (3) Place, and (4) Year, with impaired cognition indicated by an AMT4 score of less than four. Patients were assessed with the AMT. The AMT4 scores were then determined and matched against AMT scores. The performance of all 210 possible four-item combinations derivable from the AMT was assessed and ranked according to predictive efficiency (the percentage of patients whose cognition as judged by the AMT was correctly categorized by each four-item combination). SETTING: Inner-city teaching hospital. SUBJECT: Two hundred consecutive elderly patients seen on domiciliary visits, in the clinic or as orthogeriatric referrals. RESULTS: The AMT4 score showed a statistically significant correlation with AMT score (Somers' d statistic 0.90: p < 0.001). The AMT4 had a predictive efficiency of 91% and ranked 7 = /210 possible four-item combinations. CONCLUSIONS: The AMT4 may be useful in the initial assessment of cognition in elderly patients, with little loss of accuracy in detecting marked cognitive impairment when compared to the AMT. PMID- 9360038 TI - Evaluation of routine surveillance urine cultures in rehabilitation ward admissions: a prospective study. AB - OBJECTIVE: To assess the value of routine surveillance urine cultures and the prevalence of bacteriuria in the younger disabled patient subgroup admitted to the younger disabled unit (YDU). Most of these patients do require some form of assisted urinary drainage. DESIGN: A prospective study of 50 consecutive patients admitted to the YDU for short-term rehabilitation were screened by obtaining relevant clinical details and urine specimens at weekly intervals. INTERVENTIONS: Relevant clinical details were retrieved from case notes and minimum of two urine specimens were collected for culture from each patient. MAIN OUTCOME MEASURES: Presence of positive urine culture, sensitivity and clinical symptoms were recorded. RESULTS: Out of 50 patients studied, 27 were on some form of urinary drainage. Urine culture and sensitivity results were positive in 35 patients. Cultures were predominantly mixed growth or coliform organisms. CONCLUSIONS: Majority of patients were admitted with asymptomatic bacteriuria. There was no evidence to suggest that these short-term rehabilitation patients acquired nosocomial uropathogens and routine surveillance urine cultures were not particularly useful in this setting. PMID- 9360039 TI - Routing through the health care system and level of functioning of lower limb amputees. AB - OBJECTIVES: To describe the routing through the health care system and the level of functioning of a consecutive series of lower limb amputees at a general Dutch hospital. METHODS: A descriptive cohort study (medical records examination) with a follow-up interval of 11.7 months. All 124 major lower limb amputations (ankle to hip) between 1 July 1989 and 31 December 1992 are included in the study: 123 patients, average age 73.8 years, 96% vascular disease. Amputation levels are 55.3% transfemoral, 12.2% knee disarticulation and 32.5% transtibial. At follow up two patients are missing. RESULTS: Before admission to hospital 75.6% of patients are able to walk and 79.9% live independently. Discharge destinations from hospital are 22.5% home, 42.3% inpatient rehabilitation and 32.4% nursing home. At follow-up, 59% of surviving patients have a prosthesis, 47.7% are able to walk and 70.5% live independently. Mortality after one year is 28.5%. Poor preoperative walkers seem to die more often within the first year and have less chance of being fitted with a prosthesis. Poor walkers, older than 75, with diabetes mellitus and a transfemoral amputation seem to stay more often in a nursing home after one year. DISCUSSION: Although the results are largely comparable with other studies, there appear to be differences in age, amputation level and course and duration of treatment. The predicting factors found here may help the rehabilitation specialist in advising on the best moment and level of amputation and course of treatment. PMID- 9360040 TI - Hand-held dynamometry: factors influencing reliability and validity. PMID- 9360041 TI - The cytopathologist: workload, regulations, and the forgotten professional. PMID- 9360042 TI - Prediction of invasiveness by aspiration cytology applied to nonpalpable breast carcinoma and tested in 300 cases. AB - In a retrospective study, fine-needle aspirates from 300 nonpalpable breast carcinomas, including 199 invasive tumors and 101 cases of ductal carcinoma in situ, were analyzed to assess the value of 11 features in predicting invasiveness in malignant breast lesions by aspiration cytology. Four findings appeared to be useful in this context: (1) malignant cell clusters with tubular structure, (2) cytoplasmic lumen formation in malignant cells, (3) fibroblast proliferation, and (4) fragments of elastoid stroma. When any combination of two or more of these key features was seen in a smear being diagnostic of malignancy, the positive predictive value regarding invasiveness was 96%. The accuracy of this prediction in terms of sensitivity and specificity was 48% and 96%, respectively. The clinical use of these observations is discussed. PMID- 9360043 TI - Detection of high-grade cervical dysplasia: impact of age and Bethesda system terminology. AB - Pap smear, colposcopy, and biopsy results were collected from 1988-1993 at a group of family planning clinics. Positive predictive values and likelihood ratios were calculated for diagnosis of high-grade lesions based on age and Pap smear results. One thousand and forty-seven colposcopies were logged; 771 had a biopsy or endocervical curettage. Seventy-nine (10%) were high-grade lesions. If only human papillomavirus (HPV) was reported on the Pap smear, the likelihood of a high-grade biopsy was lowest (positive predictive value, 4.5%; likelihood ratio, 0.4). Women under age 25 were less likely to have high-grade biopsies (positive predictive value, 7.3%; likelihood ratio 0.7). Repeat Pap smears for atypical cells of undetermined significance (ASCUS) and low grade squamous intra epithelial lesion (LGSIL) showing only HPV in women under age 30 would have reduced the immediate colposcopy rate by 60% and delayed diagnosis by 23% of high grade lesions. Consideration of patient age and whether HPV is the only Pap smear finding may reduce referral for immediate colposcopy. PMID- 9360044 TI - Endocervical adenocarcinoma in situ: an analysis of cellular features. AB - Cytologists increasingly encounter atypical endocervical cells, because of the increasing incidence of endocervical adenocarcinoma and the use of improved endocervical sampling devices. These atypical endocervical cells can cause diagnostic problems, especially in recognizing adenocarcinoma in situ (AIS) and distinguishing it from a variety of nonneoplastic changes. We analyzed 33 cervical smears from 22 patients with confirmed AIS and compared these to 19 cervical smears from 17 patients having atypical endocervical cells of undetermined significance and negative follow-up, including at least one tissue biopsy per case, to further investigate the cytologic features of AIS. The AIS smears typically had crowded three-dimensional cellular aggregates, with markedly hyperchromatic nuclei having altered polarity. Frequently, a minor component of AIS formed strips of distinctly columnar cells or sheets. Individual AIS cells occurred in 22 (67%) smears, but these were usually inconspicuous. The AIS smears also had increased nuclear to cytoplasmic ratios (100%), enlarged nuclei (94%), feathering (88%), rosettes (85%), nucleoli (76%), apoptosis (73%), mitoses (64%), multiple nucleoli (18%), and ciliated atypical cells (3%). Cytologic features occurring significantly (P < or = 0.001) more often in AIS cases were a predominance of three-dimensional crowded aggregates (79% vs. 32%), altered nuclear polarity in most groups (88% vs. 16%), marked hyperchromasia (91% vs. 16%), apoptosis (73% vs. 26%), an increased nuclear to cytoplasmic ratio (100% vs. 63%), feathering (88% vs. 26%), and individual atypical cells (67% vs. 16%). In summary, we identified a number of architectural and cellular features that occurred significantly more often in AIS cases than in cases having atypical endocervical cells of undetermined significance and negative follow-up. PMID- 9360045 TI - Which cytological criteria are the most discriminative to distinguish carcinoma, lymphoma, and soft-tissue sarcoma? A probabilistic approach. AB - The reliability of fine-needle aspiration cytology (FNA) for distinguishing between carcinoma, lymphoma, and sarcoma was established in a previous study (Thunnissen et al., Cytopathology 1993; 4:107-114). The purpose of this study was to investigate which criteria were useful for a probabilistic diagnosis. A total of 78 randomly chosen FNA smears (31 carcinomas, 24 lymphomas, and 23 sarcomas) was sent around and read "blindly" by six cytopathologists. Each pathologist completed a list of 16 criteria for every case. Histology was used as a reference standard. A statistical analysis led to the selection of three criteria: "lymphoglandular bodies," "well-defined clusters," and "spindle-cell nuclei," associated with lymphoma, carcinoma, and soft-tissue sarcoma, respectively. Given the scores on these criteria, the probabilities to be assigned to the three diagnostic categories can be read from a table. It turns out, as one might expect, that the classification of the most probable disease is pretty reliable if one cytologic criterion scores much higher than the other two criteria. On other cases, fuzziness appears and misclassifications are far from improbable. This study offers a general cytologic approach. The cytologic criteria "lymphoglandular bodies," "well-defined clusters," and "spindle-cell nuclei" can be used both in daily practice and in education to assign posterior probabilities to carcinoma, lymphoma, and soft-tissue sarcoma. PMID- 9360046 TI - Endometrial collection and interpretation using the Tao brush and the CytoRich fixative system: a feasibility study. AB - BACKGROUND: The cytological assessment of endometrium entails: (1) a collection device that is easy to use, collects material only from the endometrium, and obtains adequate samples; (2) a fixation process that ensures the preservation of individual cells, maintains cell polarity, and allows the recognition of three dimensional tissue structures (microbiopsies); and, (3) interpretative algorithms that translate histopathologic to cytopathologic diagnoses. The purpose of this study is to show that it is feasible to achieve these ends when endometrial brush sampling is coupled with suspension fixation. METHODS: Obtain endometrium from 100 consecutive hysterectomy uteri using an Indiana University Medical Center sampler (Tao Brush), suspension-fix it in CytoRich fixative, prepare it with a cytocentrifuge using large diameter sample chambers, and compare the cytologic diagnosis to the histologic diagnosis of the hysterectomy specimen. RESULTS: There were no inadequate collections. Cytology regularly separated (1) benign endometrium, (2) low-grade (non-atypical) hyperplasia, (3) high-grade (atypical) hyperplasia/FIGO Grade I adenocarcinoma, and (4) higher-grade carcinomas from one another. Endometrial atrophy was diagnosed in three patients whose histology showed clinically asymptomatic, benign fibrous endometrial polyps. A low volume of abnormal cell aggregates interpreted as endometrial intraepithelial carcinoma was detected in one patient whose initial histology was reported as simple hyperplasia, but whose histology on review after p53 staining revealed intraepithelial surface cancer. In the remaining 96 cases, the cytologic diagnosis consistently represented the histologic diagnosis of the hysterectomy specimen. On a case-by-case basis, any one cytology slide accurately represented the diagnosis of the other cytology slides. CONCLUSION: Endometrial brushing with suspension-fixation is advocated for the detection of endometrial lesions because (1) fixation is uniform, (2) there is substantial preservation of three dimensional structures among cell aggregates, which allows pattern-based histologic diagnostic criteria to be applied to cytologic samples, and (3) only a limited number of slides need to be examined. PMID- 9360047 TI - Fine-needle sample of salivary gland lesions. V: Cytology of 22 cases of acinic cell carcinoma with histologic correlation. AB - Fine-needle sampling (FNS) of 22 acinic cell carcinomas, including 17 primary tumors, 4 local recurrences, and 1 lymph node metastasis was performed preoperatively in 17 patients. Cytologic diagnoses were concordant with histology in 3 (13.7%) cases, whereas 15 (68.2%) cases were cytologically classified as malignant, 2 (9.1%) as suspicious, and 1 (4.5%) as benign (pleomorphic adenoma). The material was unsatisfactory for cytologic evaluation in 1 (4.5%) case. Preoperative FNS technique is, therefore, useful in acinic cell carcinoma with a concordant malignant/suspicious rate of 91%. PMID- 9360048 TI - Cytologic features of 22 radial scar/complex sclerosing lesions of the breast, three of which associated with carcinoma: clinical, mammographic, and histologic correlation. AB - Radial scar/complex sclerosing lesion (RS/CSL) of the breast has become more frequently detected with the increasing performance of mammography as a screening test. The clinical, mammographic, and cytologic features of 22 cases of histologically proved breast RS/CSL, 3 of which associated with carcinoma arising at the periphery of the lesion, were reviewed. Clinical examination and mammography did not show specific features in differentiating RS/CSL from carcinoma of the breast. Cytology of RS/CSL without associated malignant changes was dominated by bland epithelial clusters and bipolar naked nuclei. Apocrine cells, papillary clusters, foam cells, and fibrillary elastoid material were also frequently seen. At the cytologic review, only one case of RS with apocrine adenosis, showing atypical cells, was diagnosed as suspicious. Two of the three cases of CSL with associated carcinoma in situ were cytologically characterized by the presence of single atypical cells. In the third case, characterized by a small tubular carcinoma near to CSL, fine-needle aspiration cytology revealed few tubular clusters without myoepithelial cells. Although cytology of RS/CSL without associated carcinoma does not seem characteristic, in most cases a diagnosis of benignancy can be performed correctly. The application of fine-needle aspiration cytology to mammographic lesions with features suggesting RS/CSL may permit a better planning of these lesions. PMID- 9360049 TI - Fine-needle aspiration cytology of mammary fibromatosis: report of two cases. AB - The purpose of this study is to evaluate cytologically two cases of mammary fibromatosis (MF). Prior to FNAC, clinical and mammographic suspicion of carcinoma and fibroadenoma were present. In both cases cytology disclosed the presence of numerous spindle cells admixed with epithelial cells. In the first case, carcinoma was excluded and the diagnosis of "spindle-cell proliferative lesion" was established. The second case was erroneously diagnosed as "cellular fibroadenoma" due to the presence of monolayered ductal epithelial groups and stromal tissue. In both cases local excision of the lesion was recommended. Although in a strict sense fibromatosis is a pure stromal lesion, the frequent presence of epithelial groups in the smears should raise a differential diagnosis with other more frequent mixed (epithelial and stromal) lesions such as fibroadenoma, cystosarcoma phyllodes, and metaplastic carcinoma. Due to the fact that clinically and mamographically MF is frequently confused with malignancy, preoperative recognition is essential since in many cases it would avoid unnecessary radical surgery. In this sense cytology offers very important preoperative information. PMID- 9360050 TI - Leiomyosarcoma metastatic to the orbit: diagnosis of fine-needle aspiration. AB - A 47-yr-old man with history of metastatic low-grade rectal leiomyosarcoma presented with progressive protrusion of his left eye due to an enlarging orbital mass. The differential diagnosis included tumor metastasis or orbital infection due to an unknown infectious agent. Diagnostic fine-needle aspiration (FNA) of the orbit was performed on an urgent basis to institute proper therapy and to save the patient's eyesight. Cytomorphologic examination of the material demonstrated a spindle-cell neoplasm consistent with metastatic leiomyosarcoma. It is a rare event for leiomyosarcoma to occur in the orbit. On our review of the literature, the cytology of primary orbital leiomyosarcoma on FNA has only been reported once. To our knowledge, this is the first report of the FNA cytomorphology of metastatic leiomyosarcoma to the orbit. PMID- 9360051 TI - Cytomorphology of adenocarcinoma of lung presenting as submandibular salivary gland mass: report of a case diagnosed by fine-needle aspiration biopsy. AB - BACKGROUND: Primary malignant neoplasms of the submandibular salivary gland (SMG) are rare, and metastatic tumors are rarer. Most of the metastases are discovered months or years after the diagnosis of the primary malignancy. Despite the increasingly used fine-needle aspiration biopsy (FNAB) in the evaluation of major salivary gland masses, diagnosis of metastases by FNAB has been only rarely studied. CASE: We report a case of lung carcinoma initially presented as a SMG swelling diagnosed by aspiration biopsy. The patient is a 52-yr-old man, a 40 pack/year smoker who also complained of weight loss and blood-streaked cough. An FNAB of the mass was consistent with metastatic adenocarcinoma with prominent signet ring-cell component of unknown primary. Subsequent studies revealed a left lung mass and left pleural effusion. The effusion cytologic examination showed malignant cells consistent with carcinoma. The patient's condition deteriorated rapidly, and he died within a few days. An autopsy revealed adenocarcinoma of lung with prominent signet ring-cell component. CONCLUSION: FNAB is a rapid, safe, reliable, and cost-efficient technique for evaluation of major salivary glands lesions. To our knowledge, this case is the first lung carcinoma presenting as SMG mass initially diagnosed on FNAB. PMID- 9360052 TI - Basaloid squamous carcinoma metastatic to renal-cell carcinoma: fine-needle aspiration cytology of tumor-to-tumor metastasis. AB - We describe an unusual case of a basaloid squamous-cell carcinoma (BSCC) of the tonsil in a 56-yr-old man that metastasized to a primary renal-cell carcinoma (RCC) and the lung. The diagnosis of the second primary, the RCC, was based on fine-needle aspiration (FNA) cytology. A subsequent nephrectomy specimen revealed BSCC metastatic to RCC, clear-cell type. Retrospective analysis of the FNA of the renal mass revealed classic RCC morphology and, in addition, another cytologically distinctive pattern characterized by occasional sheets of cohesive neoplastic cells with hyperchromatic nuclei and nuclear molding representative of BSCC. The cytologic features of a subsequent FNA of the lung were characteristic of metastatic BSCC. Our retrospective analysis of cytologic material from the renal mass underscores the importance of raising the possibility of tumor-to tumor metastasis when distinctly different morphologic features are seen in an otherwise typical cytology of a neoplasm in patients with an already known or suspected second primary. To our knowledge, this case report is the first one documenting metastasis of BSCC to RCC. PMID- 9360053 TI - Villoglandular adenocarcinoma of the cervix: cytologic presentation. AB - Villoglandular adenocarcinoma of the uterine cervix is a recently described neoplasm which occurs primarily in young women and has an excellent prognosis. In many instances, these lesions may be treated conservatively with cervical conization rather than hysterectomy, a therapeutic option of particular importance for young women who wish to preserve reproductive capability. This paper describes the cytologic findings on cervical smears from three women with villoglandular adenocarcinoma, two treated conservatively with cervical conization and one managed with hysterectomy. Characteristic cytologic features in these cases included the presence of long villous fronds and papillae lined by columnar cells with intact cytoplasmic borders and minimal to moderate cytologic atypia. Also noted were strips and three-dimensional ball-like clusters of cells with smooth, intact communal cytoplasmic rims. Apoptotic bodies and scattered mitoses were observed. Recognition of the above features warrants inclusion of this entity in the cytologic differential diagnosis, with conservative histologic follow-up prior to more radical therapeutic measures. PMID- 9360054 TI - Immunocytochemistry on the Thinprep processor. AB - INTRODUCTION: For cytologic specimens, the vast majority of immunocytochemical studies (ICC) are performed on non-gynecologic specimens for diagnostic purposes, and they can be performed on unstained or previously stained direct smears. Although the ThinPrep processor (TPP) has been approved for the preparation of non-gynecologic specimens, there is scant literature describing the utility of ICC methodology on cytology specimens fixed and processed by this method. MATERIALS AND METHODS: Forty-one fresh specimens were obtained from the surgical gross room and aspirated or scraped to collect cells for thin layer (TL) and direct smears (DS). Specimens included a variety of neoplastic and nonneoplastic samples that were either Papanicolaou (P) stained or unstained (US). One group of US TL slides was subjected to antigen retrieval (AR). Staining was graded semiquantitatively. Each sample acted as its own control. Antibodies (abs) included: CAM5.2, AE1/3, K903, vimentin, MSA, desmin, s-100, HMB45, PSA, PAP, chromogranin, NSE, insulin, synaptophysin, pCEA, mCEA, mCEAD14, LCA, L26, UCHL-1, OPD-4, thyroglobulin, GCDFP, ER/PR, laminin, collagen IV, PLAP, HCG, CD68, HAM56, and MAC387. RESULTS: Semiquantitative staining overall results comparisons: TLP > DSP TLP < DSP TLP = DSP TLUS > DSUS 11/25 (44%) 6/25 (24%) 8/25 (32%) 9/24 (38%) TLUS < DSUS TLUS = DSUS 3/24 (12%) 12/24 (50%) TLP Vs. TLUS TLP > TLUS TLP < TLUS TLP = TLUS 8/41 (20%) 9/41 (22%) 24/41 (58%) There were five false-negative results, 2 with TL and 3 with DS, and 1 false-positive TL. DISCUSSION: Immunocytochemistry performed on the ThinPrep Processor showed equal or greater intensity and distribution of proper staining when compared to direct smears with the following advantages: (1) cleaner background, easier to interpret; (2) less abs required in a smaller area; (3) IPX can be done on Papanicolaou-stained thin layer slides; (4) thin layer slides can be modified for multiple abs tests; (5) additional thin layer slides can be prepared for ICC bases on needs. No significant differences of immunostaining were seen when comparing thin layer Papanicolaou-stained and unstained slides. Antigen retrieval offered no advantage in this study. PMID- 9360055 TI - The single seizure. To treat or not to treat? AB - It is generally accepted that anticonvulsant therapy should be offered once a patient has experienced 2 or more seizures. However, there is controversy over whether treatment should be offered after a single seizure. The type of epileptic event that has occurred may determine whether or not a single episode will bring the individual to medical attention. In individuals who experience a single seizure, there is significantly increased risk of recurrence if neurological or paroxysmal electroencephalogram abnormalities are present or if the seizure is partial. Anticonvulsant therapy, if taken as prescribed after a single seizure, will substantially reduce the risk of seizure recurrence. Unless a further seizure would hold little disadvantage, early treatment probably offers distinctly more benefit than hazard. No data are available to indicate the most appropriate duration of therapy after a single seizure. PMID- 9360056 TI - Antifungal resistance trends towards the year 2000. Implications for therapy and new approaches. AB - Medical advances have led to increased numbers of immunocompromised patients living longer. Coinciding with this increase in the immunocompromised patient population is an increase in the number of clinically significant fungal infections. Unfortunately, widespread use of the limited numbers of antifungal agents to treat these infections has led to the development of drug resistance. Thus, in an attempt to sort out the mechanisms of resistance for each of the systemically useful antifungal agents, a comprehensive review of the literature has been carried out. The most common mechanisms for the development of resistance involve changes in the enzymatic pathways which serve as the drug targets. For instance, changes in enzymes responsible for the biosynthesis of ergosterol, the target of azole activity, lead to azole resistance. Another common mechanism used by fungi to avoid drug toxicity includes reduced intracellular accumulation of the drug through both decreased permeability and energy-dependent efflux pumps. Using our current understanding of the mechanisms of drug resistance as a template, several strategies to overcome resistance have been identified. These include improvement of host immune function, the use of adjuvant surgery, the development of new drug delivery systems for currently available drugs and the development of new classes of antifungal agents. Also, clinical trials to establish appropriate drug doses and duration of therapy are needed, as well as the benefits of antifungal prophylaxis explored and the use of combination therapies entertained. The war against drug resistant fungi has been identified as we approach the year 2000. With careful and cogent investigations, we do have the tools to fight back against these opportunists. Of all the strategies reviewed, however, in our opinion, the development of new antifungal drugs is likely to have the most significant future impact on our management of drug resistance in fungal infections. PMID- 9360060 TI - Clopidogrel. AB - Clopidogrel is a thienopyridine that irreversibly inhibits platelet aggregation by selectively binding to adenylate cyclase-coupled ADP receptors on the platelet surface. In animal models, clopidogrel reduced the formation of both arterial and venous thrombi. After oral administration, clopidogrel is rapidly absorbed and undergoes metabolic activation in the liver. The principal circulating metabolite is SR 26334, an inactive carboxylic acid derivative. The active metabolite is not yet known. Findings of a large, well controlled study of clopidogrel versus aspirin in patients with atherosclerotic vascular disease (CAPRIE study) indicate that clopidogrel has superior efficacy in terms of prevention of ischaemic stroke, myocardial infarction and vascular death. Clopidogrel-treated patients experienced less frequent gastrointestinal upset, abnormal liver function and gastrointestinal haemorrhage than patients who received aspirin, but more frequent rash and diarrhoea. Neutropenia and thrombocytopenia occurred rarely and at similar rates in both groups. PMID- 9360059 TI - Recognition, management and prophylaxis of endocarditis. AB - Infective endocarditis (IE) remains a disease with high morbidity and mortality. In recent years, a higher frequency of IE has been observed in the elderly, in intravenous drug users and in patients with prosthetic valves. The diverse manifestations of this disease demand a high degree of suspicion from the practitioner, in order to make an early diagnosis. Advances in and increasing use of echocardiography (especially transoesophageal) allow us to identify valvular changes earlier and more precisely. The use of the new Duke's diagnostic criteria, based on clinical manifestations and microbiological and echocardiographic findings, facilitates the diagnosis and categorisation of IE. An increase in staphylococci and other problem pathogens, such as penicillin resistant streptococci, enterococci resistant to beta-lactams, aminoglycosides and methicillin-resistant staphylococci has been observed. Important changes have also taken place in the management of IE. There is a clear trend towards the use of shorter treatment courses, oral and once-daily regimens and outpatient programmes, all of which aim to reduce costs and provide patients with improved quality of life. Antibiotic prophylaxis for the prevention of IE is still controversial. In the past few years more rational regimens have been used, and indications are now more precise. In spite of all this, however, few cases are prevented and patient compliance to the prophylaxis regimens remains low. PMID- 9360061 TI - Topiramate. A review of its pharmacodynamic and pharmacokinetic properties and clinical efficacy in the management of epilepsy. AB - Topiramate is a sulphamate-substituted monosaccharide derived from D-fructose and is structurally unrelated to other antiepileptic drugs. It acts by multiple mechanisms that suggest it may be effective in several types of epilepsy. In double-blind placebo-controlled trials, add-on therapy with topiramate 400 to 1000 mg/day reduces the seizure rate by > or = 50% in 35 to 52% of adult patients with resistant partial epilepsy (with or without secondarily generalised seizures) compared with 0 to 19% of placebo recipients; a 200 mg/day dosage was less effective. Topiramate has also been shown to be superior in efficacy to placebo in well controlled trials in patients with generalised tonic-clonic seizures, Lennox-Gastaut syndrome and in paediatric patients with partial epilepsy. Efficacy has been maintained for 7 years and some patients may also be satisfactorily treated with topiramate monotherapy. Further study is needed to follow up on the promising results of topiramate use in other paediatric epilepsies. Adverse CNS events are the most common untoward effects during topiramate therapy and are most likely to lead to withdrawal of the drug. However, most adverse events are mild to moderate in severity and lessen with continued drug therapy. In clinical trials, most adverse events which were dose limiting or led to discontinuation of treatment occurred during the titration phase. The overall incidence of adverse events may be reduced by slower upward dosage titration. In summary, topiramate appears to be a suitable agent for add on therapy in adult patients with partial epilepsy. Preliminary reports support the use of add-on topiramate in adults with generalised epilepsy, in childhood epilepsies and in patients with Lennox-Gastaut syndrome, as well as the use of topiramate monotherapy in patients with partial epilepsy. Thus, topiramate can be considered an important new drug for the management of patients with refractory epilepsy. PMID- 9360058 TI - A comparative review of colony-stimulating factors. AB - The efficacy of dose-intensive chemotherapy in oncology is limited by the duration and severity of neutropenia. Several recombinant DNA factors that alter neutrophil proliferation and function, and are characterised by their ability to stimulate colony formation of myeloid progenitors in vitro, have been shown to alter clinical sequelae associated with neutropenia in vivo. Two of these factors, granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF), have been approved by the US FDA. One other factor, macrophage colony-stimulating factor (M-CSF), is approved as indicated therapy in Japan. The clinical effects of these agents are compared in this review. Results of clinical trials suggest that the efficacy of G-CSF is greatest when used as an agent to enhance circulation of stem cells and pre-colony-forming progenitor cells. It is also an effective agent in reducing the duration of neutropenia following dose-intensive chemotherapy, thereby leading to a reduction in the incidence of febrile neutropenia. Similar observations were made with GM CSF, although toxicity with the latter agent appears to be moderately greater than that observed with G-CSF. Functional activity of GM-CSF is broader than that of G-CSF, in that macrophages are affected by GM-CSF. As a result, some data suggest that GM-CSF may be more applicable to patients with a high risk of infection. There is a suggestion that M-CSF assists neutrophil recovery, although this effect may be indirect, via the induction of other cytokines. The predominant effect of M-CSF appears to be enhancement of macrophage and monocyte function, which may reduce the severity and duration of fungal infection. PMID- 9360057 TI - Metronidazole. A therapeutic review and update. AB - The nitroimidazole antibiotic metronidazole has a limited spectrum of activity that encompasses various protozoans and most Gram-negative and Gram-positive anaerobic bacteria. Metronidazole has activity against protozoans like Entamoeba histolytica, Giardia lamblia and Trichomonas vaginalis, for which the drug was first approved as an effective treatment. Anaerobic bacteria which are typically sensitive are primarily Gram-negative anaerobes belonging to the Bacteroides and Fusobacterium spp. Gram-positive anaerobes such as peptostreptococci and Clostridia spp. are likely to test sensitive to metronidazole, but resistant isolates are probably encountered with greater frequency than with the Gram negative anaerobes. Gardnerella vaginalis is a pleomorphic Gram-variable bacterial bacillus that is also susceptible to metronidazole. Helicobacter pylori has been strongly associated with gastritis and duodenal ulcers. Classic regimens for eradicating this pathogen have included metronidazole, usually with acid suppression medication plus bismuth and amoxicillin. The activity of metronidazole against anaerobic bowel flora has been used for prophylaxis and treatment of patients with Crohn's disease who might develop an infectious complication. Treatment of Clostridium difficile-induced pseudomembraneous colitis has usually been with oral metronidazole or vancomycin, but the lower cost and similar efficacy of metronidazole, coupled with the increased concern about imprudent use of vancomycin leading to increased resistance in enterococci, have made metronidazole the preferred agent here. Metronidazole has played an important role in anaerobic-related infections. Advantages to using metronidazole are the percentage of sensitive Gram-negative anaerobes, its availability as oral and intravenous dosage forms, its rapid bacterial killing, its good tissue penetration, its considerably lower chance of inducing C. difficile colitis, and expense. Metronidazole has notable effectiveness in treating anaerobic brain abscesses. Metronidazole is a cost-effective agent due to its low acquisition cost, its pharmacokinetics and pharmacodynamics, an acceptable adverse effect profile, and its undiminished antimicrobial activity. While its role as part of a therapeutic regimen for treating mixed aerobic/anaerobic infections has been reduced by newer, more expensive combination therapies, these new combinations have not been shown to have any therapeutic advantage over metronidazole. Although the use of metronidazole on a global scale has been curtailed by newer agents for various infections, metronidazole still has a role for these and other therapeutic uses. Many clinicians still consider metronidazole to be the 'gold standard' antibiotic against which all other antibiotics with anaerobic activity should be compared. PMID- 9360063 TI - Drug treatment and schizophrenia in the 1990s. PMID- 9360062 TI - Mibefradil. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in the management of hypertension and angina pectoris. AB - Mibefradil belongs to a new class of calcium antagonists, the tetralol derivatives. It selectively blocks T-type calcium channels in contrast to other calcium antagonists which block only L-type channels. Mibefradil relaxes coronary arteries without suppressing myocardial contractility and causes a dose-related decrease in heart rate. When given orally once daily to patients with hypertension mibefradil produces a dose-related decrease in blood pressure which is sustained for 24 hours and improves exercise performance in patients with stable angina pectoris. In patients with generally mild to moderate hypertension oral mibefradil was superior to nifedipine SR and diltiazem CD, tended to be more effective than nifedipine GITS and had similar efficacy to amlodipine. Mibefradil 50 to 100mg once daily also has antianginal and anti-ischaemic effects. The drug improves the duration of symptom-limited exercise and the time to onset of ischaemia, and reduces the frequency of anginal attacks and consumption of nitroglycerin. Its efficacy is similar to that of diltiazem and tends to be greater than that of amlodipine in patients with stable angina. Mibefradil is generally well tolerated and is associated with a lower incidence of leg oedema than amlodipine and nifedipine. Thus, mibefradil is a calcium antagonist with a predictable cardiovascular profile, which, on the basis of available clinical data, is an effective alternative to other drugs widely used in the treatment of hypertension and stable angina pectoris. PMID- 9360065 TI - Establishing a protocol to quantify leaflet fibroblast responses to physiologic flow through a viable heart valve. AB - Mechanical stresses are thought to affect the metabolism of a variety of cell types. Little quantitative data exist regarding heart valve leaflet fibroblast activity after dynamic loading. The goal of this study was to examine leaflet fibroblast function and differentiation in response to flow through an intact valve. This requires the development of a flow system capable of reproducing the valve's native environment, as well as assay protocols to analyze cellular viability and protein and collagen synthesis. As a tool to expose viable tissue valves to physiologic flow, a sterilizable pulsatile flow system has been developed to recreate the dynamic flow environment of the aortic valve while preventing contamination from room air. Physiologic flow conditions [frequency 70 bpm, aortic pressure 129/82 mmHg (systolic/diastolic), cardiac output 2.3 L/min] were sustained for 71 hr without microbiologic contamination. Analytic tools for assessment of fibroblast function include a viability assay, which demonstrated that leaflet viability decreases after prolonged exposure to antibiotics. Proline incorporation studies revealed that 11 times more protein is retained by leaflet tissue than is released into the medium, and 27% of this protein is collagen. Polyacrylamide gel electrophoresis clearly resolved collagen Types I and III from both prepared standards as well as leaflet extracts. In ongoing work, the sterile flow loop will be used to expose fresh porcine aortic valves to defined flow conditions, and the viability and protein/collagen biosynthetic activity of leaflet fibroblasts in response to flow will be quantified. These experiments will provide a baseline by which to design and evaluate future tissue engineered substitutes. PMID- 9360066 TI - Successful prosthetic mitral valve implantation in pigs. AB - Clotting mechanisms, the coagulation cascade, platelet function, and platelet leukocyte-endothelial cell interactions are all very similar in humans and pigs. Because of these similarities, the authors concluded that the pig would be an ideal model for the study of thromboembolism resulting from prosthetic heart valves. To date, they have successfully recovered a total of 11 pigs (52.9 +/- 8.1 kg), 3 with bioprosthetic valves and 8 with mechanical valves, all in the mitral position (25 mm od). The normal presence of high numbers of pulmonary endothelial macrophages and other unique aspects of porcine cardiovascular and pulmonary function dictate somewhat different surgical protocols than those normally used for human patients and ruminant species. Some of these special procedures include 1) crystalloid prime without the use of plasma volume expanders, especially those with a starch base; 2) pharmacologic protection against arrhythmias (lidocaine, 4 mg/kg); 3) special attention to adequate hypothermic cardioprotection during the time of cross-clamp; 4) the use of shock doses of corticosteroid (prednisolone sodium succinate, 0.5 mg/kg) before removal of the aortic cross-clamp; and 5) positive inotropic support (dopamine, 0.008 mg/kg) while weaning from cardiopulmonary bypass. Gamma camera images of 111In tagged autologous platelets 24 hours after surgery show most thrombi located on the sewing ring with fewer on the pledgets and anchor sutures. The latter observations were confirmed by quantification of platelet deposition using a gamma counter. PMID- 9360064 TI - Dynamic characterization of a new accelerated heart valve tester. AB - This paper presents a new accelerated prosthetic heart valve tester prototype that incorporates a camshaft and poppet valves. A three element Windkessel system is used to mimic the afterload of the human systemic circulation. The device is capable of testing eight valves simultaneously at a rate up to 1,250 cycles/min, while the flow rate, the pressure, and the valve loading can be monitored and adjusted individually. The tester was characterized and calibrated using a set of eight Carpentier-Edwards bioprostheses at a flow rate varying between 3 and 5 L/min. The experiment was carried out with the pressure difference across the closed heart valve maintained between 140 and 190 mmHg. Smooth and complete opening and closing of the valve leaflets was achieved at all cycling rates. This confirms that the velocity profiles approaching the test valves were uniform, an important factor that allows the test valves to open and close synchronously each time. PMID- 9360068 TI - Dynamic change in the left ventricular base with or without a rigid mitral valve prosthesis. AB - To evaluate the narrowing of the left ventricular outflow tract (LVOT) during systole caused by a rigid mitral prosthesis, the geometric relationship between the prosthesis (or the mitral annulus) and the left ventricular base (LVB) was studied in five patients with mechanical mitral valve prostheses and eight normal subjects. The images of the mitral valve annulus (MVA) and the LVOT orifice reconstructed in three dimensions were projected on the plane of the LV base. Calculating the areas of these projected images (i.e., those for MVA [Sm], LVOT orifice [So], the LVB [Sb; Sb = Sm + So]), the MVA-LVB ratio (Sm/Sb) was determined. In the normal subject, the MVA-LVB ratio was nearly constant during systole (59 +/- 5% at 0 msec and 62 +/- 7% at 300 msec, respectively), whereas in the patients with prostheses, the ratio increased from 61 +/- 4% (0 msec) to 69 +/- 4% (300 msec). The increase in MVA-LVB ratio reduces the proportionate share of LVOT orifice in relation to the total LVB. The ideal mitral valve prosthesis should be flexible at the annulus to attain good performance in LVB dynamics. PMID- 9360067 TI - Three-dimensional coupled fluid-structure simulation of pericardial bioprosthetic aortic valve function. AB - A computational, three-dimensional coupled fluid-structure dynamics model was developed for a generic pericardial aortic valve in a rigid aortic root graft with physiologic sinuses. Valve geometry was based on that of the natural valve. Blood flow was modeled as pulsatile, laminar, Newtonian, incompressible flow. The structural model accounted for material and geometric nonlinearities and also simulated leaflet coaptation. A body fitted grid was used to subdivide the flow domain into computational finite volume cells. Shell finite elements were used to discretize the leaflet volume. A finite volume computational fluid dynamics code and finite element structure dynamics code were used to solve the flow and structure equations, respectively. The fluid flow and structural equations were coupled using an implicit "influence coefficient" technique. Physiologic ventricular and aortic pressure waveforms were prescribed as the flow boundary conditions. The aortic flow field, valve structural configuration, and leaflet stresses were computed at 2 msec intervals. Model predictions on aortic flow and transient variation in valve orifice area were in close agreement with corresponding experimental in vitro data. These findings suggest that the computer model has potential for being a powerful design tool for bioprosthetic aortic valves. PMID- 9360069 TI - Hydrodynamics of a long-body bileaflet mechanical heart valve. AB - A new bileaflet substitute mechanical heart valve (MHV) that incorporates an optimal length-to-annulus ratio for improved hydrodynamic efficiency was recently introduced. Efforts have been made on this new prosthesis to use the current advances in carbon materials and design technology to achieve higher net forward flow with minimal energy loss for the smaller aortic valves, while reducing regurgitant closure volume for the larger size valves by an elongated orifice. Benchtop experiments performed in a pulsatile flow loop, under simulated physiologic conditions, substantiated these improvements as claimed. PMID- 9360070 TI - Comparison of the closing dynamics of mechanical prosthetic heart valves. AB - To compare the closing dynamics of mechanical tilting disk prosthetic heart valves (OmniScience 25 [OS25], Medtronic-Hall 25 [MH25], Bjork-Shiley Monostrut 29 [BS29]) and bileaflet valves (CarboMedics 29 [CM29]) in the mitral position, an x-ray high speed video camera (XHVC) and a mechanical mock circulator were used. From the continuous images taken with the XHVC, the starting point of closing and the period during closing (PDC) were measured. Pressures and flow rate were recorded at 500 Hz synchronously with the XHVC. A pressure difference across the valves at the onset of closing (dpc) was newly introduced to compare the closing response. Using 60 and 100 bpm, the following results were obtained: 1) the CM29 had less PDC and maximum backflow rate than the BS29; 2) the dpc and the PDC at 100 bpm were larger than those at 60 bpm; 3) the dpc of the MH25 was the lowest; and 4) the PDC of the CM29 was the shortest. With regard to the effect of valve design on closing dynamics, it was shown that: 1) less momentum of inertia of the occluder and disk traveling angle resulted in lower dpc and shorter PDC, and 2) the higher the dpc and the PDC became, the larger the maximum backflow rate that was generated, and 3) low final closing speed will be achieved for small disk travelling angle. PMID- 9360071 TI - Analysis of subcutaneous fluid in rats. AB - Subcutaneous implantation in rats is a commonly used model for biomaterial calcification studies. Although this model is frequently used, its components have not been characterized with respect to calcification. Exudate from the subcutaneous spaces of 18 young rats was collected using diffusion chambers. These chambers consisted of polymethylmethacrylate tubes with 0.22 micron pore filters covering each end allowing fluid, but not cells, to enter the chambers. Glutaraldehyde treated bovine pericardial strips were implanted subcutaneously, inside the chambers and outside the chambers, to test the calcification inducing abilities of the various environments. The animals were killed on postoperative day 10, and the exudate and materials were collected. The exudate was analyzed for ionic calcium, total calcium, inorganic phosphorus, and albumin, and for cells by a differentiated cell smear. The materials were analyzed for calcification by radiography, histology, and atomic absorption. Calcification was present in the materials inside the chambers where no cells were present and in the materials that were not in chambers. The distinct features of the exudate were elevated ionic calcium, a high Ca x P product, and elevated phosphorus. PMID- 9360072 TI - A stable ovine congestive heart failure model. A suitable substrate for left ventricular assist device assessment. AB - Similarities in coronary circulation and heart size of sheep to that of humans are specific advantages of a sheep model of congestive heart failure (CHF). CHF was created in 11 sheep (51 +/- 4 kg) by selective sequential intracoronary injection of 90 microns microspheres under 1.5% isoflurane anesthesia. Hemodynamic characteristics were assessed at baseline, 4 weeks after establishment of CHF (ejection fraction [EF] < 35%, n = 11), and 26 weeks (n = 7) later. Baseline echocardiographic EF was 59 +/- 5% and fell to 26 +/- 5% after 5 +/- 2 embolizations. The left ventricular (LV) pressure-volume relationship showed stable decreases in LV end-systolic elastance (Ees) and preload recruitable stroke work. Intravenous infusion of dobutamine increased Ees from 2.8 +/- 1.7 to 4.3 +/- 2.2 and 4.5 +/- 1.4 mmHg/ml at heart rates of 140 and 160/min, respectively, at baseline. Increases of Ees (from 1.3 +/- 0.5 to 2.3 +/- 0.7 and 1.9 +/- 0.5 mmHg/ml at heart rates of 140 and 160/min, respectively) with dobutamine under CHF conditions did not exceed Ees values at baseline without dobutamine. This response to dobutamine infusion did not change 26 weeks after establishment of CHF. This stable ovine CHF model is proposed for studies on the long-term effects of cardiac assist devices. PMID- 9360073 TI - In vivo left ventricular assist induced coagulation derangements. Comparison of Sarns-3M and St. Jude Medical circuits. AB - An in vitro comparison of centrifugal pumping systems manufactured by Sarns-3M and St. Jude Medical revealed a difference in blood cell derangement. The purpose of this study was to compare in vivo the effects of 96 hr of left ventricular assist (LVA) on indexes of coagulopathy, hemolysis, and complement activation. Two groups of calves (each: n = 5) were instrumented with identical left atrial to thoracic aorta centrifugal pumping circuits using either Sarns-3M or St. Jude centrifugal pumps. Laboratory evaluations were performed pre-assist and at 1, 4, 24, 48, 72, and 96 hr during LVA. Platelet counts dropped significantly by 24 hr (Sarns-3M: 28%; St. Jude: 30%); no significant change in function was noted. Activated clotting time increased slightly (p > 0.05). Prothrombin time increased at 4 and 24 hr of LVA, returning to baseline by 96 hr (p < 0.05). Activated partial thromboplastin time increased with the St. Jude device from 24 to 96 hr on LVA (p < 0.05); the increase with the Sarns-3M device never reached significance. No significant changes in lactate dehydrogenase or plasma free hemoglobin were detected. Complement fraction C5a rose by 1 hr of LVA (p < 0.05), peaking at 4 hr and returning to baseline by 96 hr with both pumps. No significant difference was detected between pump groups for any of the parameters. It was concluded that 1) 96 hr Sarns-3M and St. Jude LVA caused coagulation derangement in calves, 2) neither pump demonstrated an advantage regarding coagulation and complement parameters, 3) hemolysis observed with the Sarns-3M pump in vitro was not evidenced in vivo, and 4) in vitro evidenced centrifugal pump differences may not be realized in vivo. PMID- 9360075 TI - Mechanical unloading with a miniature in-line axial flow pump as an alternative to cardiopulmonary bypass. AB - Cardiopulmonary bypass (CPB) causes a well described systemic inflammatory response. To avoid these potential detrimental effects, coronary artery bypass grafting (CABG) has been attempted off CPB on the beating heart. With the use of a left ventricular (LV) assist device during CABG, the heart can be made flaccid with beta-blockade, and the systemic circulation can continue to be supported. The hemodynamic and hematologic consequences of left heart bypass with a miniature axial flow pump were studied in a sheep CABG model. The pump weighs 45 g and was connected to standard venous and arterial cannulas. Left sided inflow and brachiocephalic outflow were employed. A pump speed of 14,000 rpm resulted in a flow of 5.63 +/- 0.18 L/min and provided 75% of the LV output during a 2 hr pump run. This resulted in complete capture of the aortic pressure tracing (mean 56.3 mmHg) with a 15.5 mmHg augmentation in the esmolol depressed ventricle. Reductions in LV end diastolic pressure and LV end systolic pressure resulted in a 66% reduction in LV external work under baseline conditions and an 83% reduction in the beta-blocked ventricle. Myocardial oxygen demand was reduced 16% after axial flow unloading in the esmolol depressed condition. Right ventricular pressures, pulmonary artery flow, LV filling, and oxygenation were adequate in the esmolol depressed animal and remained unchanged throughout the experiment. No changes in hematocrit, total bilirubin, lactate dehydrogenase, or plasma free hemoglobin were detected after 2 hr of assist. Axial flow left heart bypass results in acceptable hemodynamics with no hemolysis and may provide an alternative to CPB during CABG. PMID- 9360074 TI - Hemodynamic effect of inhaled nitric oxide in dilated cardiomyopathy patients on LVAD support. AB - Recently it has been shown that inhaled nitric oxide (NO), which has been proven to contribute to improvement in critical pulmonary hypertension, may provide a favorable effect early after left ventricular assist device (LVAD) support. To improve right ventricular function, inhalation of NO was added to treatment with conventional catecholamines for four consecutive dilated cardiomyopathy (DCM) patients following institution of LVAD. In two patients 1 hr after inhalation of NO, central venous pressure (CVP), mean pulmonary arterial pressure (PAm), and pulmonary vascular resistance (PVR) were improved. These results led to better LVAD output and resulted in an adequate cardiac index. On the other hand, a right VAD (RVAD) was implemented in one patient whose high CVP, PAm, and PVR continued; he was weaned after 8 days of RVAD support. Another patient who had a high CVP but normal PAm and PVR before and after inhalation of NO had no improvement in his hemodynamic state. These data suggest that inhaled NO may improve systemic circulation by reducing right ventricular afterload and may become a promising and convenient therapy before placing RVAD in DCM patients under LVAD support. RVAD should be conducted in patients with right ventricular failure or when pulmonary hypertension is associated with impaired right ventricular reserve, even after inhalation of NO. PMID- 9360076 TI - Ex vivo resuscitation of kidneys after postmortem warm ischemia. AB - An ex vivo resuscitation of kidney function following substantial post mortem warm ischemia was attempted with the ultimate goal of overcoming the ischemic barriers in organ retrieval for transplantation. The resuscitation technology involved reperfusion at 32 degrees C with an acellular solution to reinstitute oxidative metabolism of sufficient magnitude to restore function after a substantial postmortem warm ischemic insult. The ability to resuscitate renal function at various time periods postmortem was evaluated. Resuscitation parameters included perfusion pressures, vascular flow rates, vascular resistances, restoration of diuresis with concordant urinary creatinine concentrations, and blinded histologic evaluations. The results of this study suggest that it may one day be feasible to resuscitate organs following as much as 2 hr of postmortem warm ischemia for clinical transplantation. An expanded donor pool consisting of allografts resuscitated post mortem from what is now considered to be the "non retrieval donor" could help alleviate the chronic organ shortage. Furthermore, since organs resuscitated ex vivo at 32 degrees C exhibited ongoing metabolism, which was artificially supported rather than inhibited by traditional hypothermia, diuresis was restored. The ability to collect and analyze urine during organ resuscitation and preservation may present the opportunity to assess organ function prospectively. PMID- 9360077 TI - Heparin induced thrombocytopenia. Experiences in 12 heart surgery patients. AB - A heparin induced thrombocytopenia Type II (HIT) is a dangerous complication of heparin therapy. Bleeding, but above all serious thromboembolic complications, which may result in crippling disabilities or even death, can develop. Twelve heart surgery patients who were diagnosed with a HIT Type II are reported. Seven of the patients were diagnosed post operatively, the other five pre-operatively. Two of these patients underwent heart surgery with r-Hirudin (Behringwerke AG, Marburg, Germany) on cardiopulmonary bypass and two on Orgaran (AKZO Organon, the Netherlands). Of the seven post operative HIT patients, four had had a bypass operation and each had received a mitral or aortic valve replacement. Another patient had received an artificial biventricular support system (Berlin Heart) and was diagnosed with HIT Type II post operatively. Because of his special condition, this patient underwent anticoagulation with Orgaran and heart transplantation with Orgaran on a heart lung machine. Upon suspicion of HIT Type II, heparin therapy was immediately halted and an alternative treatment of Orgaran or r-Hirudin was begun. One patient encountered bleeding of a gastric ulcer on Orgaran therapy. Heart surgery patients, especially patients with an artificial support system, are potentially lethally threatened by serious thromboembolic complications accompanying HIT Type II. Therefore, these patients must be diagnosed as early as possible. Orgaran along with r-Hirudin are effective heparin substitutes in patients with HIT Type II. These medications can be widely administered to heart surgery patients pre-, intra-, and post operatively without complication. PMID- 9360078 TI - Coupling of skeletal muscle to a prosthesis for circulatory support. AB - A durable bond between the end of skeletal muscles and prosthetic structures could, with appropriate linkage, allow circulatory support power by synchronous and/or sequential contraction of several in situ conditioned muscles. Potential advantages relative to a myoplasty wrap involve 1) less traumatic dissection, 2) efficient linear force development, 3) selectable contraction rate, 4) greater stroke work, 5) independent control of muscle pre-load and end diastolic pressure, and 6) independent control of duration of muscle tension and ejection time. However, no existing means of tissue-prosthetic bonding appears adequate. Practicality would demand that full tension bearing capacity by the bond take no longer than muscle conditioning. A prosthesis was developed to achieve those goals. As scaled for this study, it is made of 7,200-7,800 unspun, unplaited, 22 to 26 microns diameter polyester fibers swaged into four taper needles for weaving through distal muscle. The other end is formed into a polyurethane sheathed kernmantel cord for distal fixation. Devices were implanted in six 3 to 4 kg rabbits (unilateral posterior tibial tendon replacement, random side selection with contralateral dissection/closure controls), and their tensile strength was tested at 30 days. All healed well; leg movements were normal after 1 week. Limbs were frozen at -70 degrees C between death and testing. Control failure occurred at 243 +/- 94 N and experimental at 163 +/- 44 N (p = 0.065, t test); highest estimated requirement was 17.2 N. Interface strength was adequate by 30 days. Continued investigations, addressing other questions, are warranted. PMID- 9360079 TI - Extracorporeal life support as a post left ventricular assist device implant supplement. AB - Extracorporeal life support (ECLS) is indicated following left ventricular assist device (LVAD) implant for right heart failure or pulmonary dysfunction. From December 1991 to December 1996, 100 patients were supported with the implantable HeartMate LVAD. Of these, 12 patients were supported with ECLS post LVAD implant. Pre-operatively, 10 patients (83%) were on an intra-aortic balloon pump, 9 patients (75%) were intubated, and 8 patients (67%) required ECLS bridge to LVAD implant. Six patients (50%) were men, and patient age ranged from 28 to 63 years (mean 46 +/- 10 years). Duration of ECLS averaged 3 +/- 2 days (range, 1-9 days). Eight patients (67%) required a right ventricular assist device (RVAD) with an ECLS circuit, three patients (25%) required peripheral veno-venous ECLS, and one patient peripheral veno-arterial ECLS. Forty-five percent supported with ECLS post LVAD survived to transplant compared with the 81% supported with LVAD only. Early in this experience, three patients had RVAD support only and all three patients died. RVAD support (with or without ECLS) was 11% overall and declined from 14% in the first 50 patients to 8% in the second 50. ECLS post LVAD is relatively uncommon and its use is associated with reduced survival, but helps salvage these critically ill patients. PMID- 9360080 TI - Venovenous extracorporeal life support for patients after cardiotomy. AB - Pulmonary edema and acute lung injury are common sequelae after cardiopulmonary bypass. Increased ventilatory support improves gas exchange, but may compromise ventricular function. From July 1994 to February 1997, nine patients were supported with veno-venous (V-V) extracorporeal life support (ECLS) for post cardiotomy respiratory failure. The mean age was 53 +/- 13 years (range: 37-80 years), and eight (89%) were men. Pre-operatively, five of nine (56%) were intubated, three (33%) were supported with an intra-aortic balloon pump, and five (56%) were on veno-arterial ECLS. Four patients were post left ventricular assist device (LVAD) implantation, one each after resection of an aortic aneurysm, mitral valve replacement and bypass grafting, aortic valve replacement, and pulmonary embolectomy and heart transplantation. Mean duration of support was 2 +/- 1 days (range: 1-4 days). Patients were intubated for a mean of 2 +/- 22 days (range: 4-71 days). One patient (11%) required mediastinal re-exploration secondary to bleeding, two patients underwent hemodialysis or ultrafiltration, and seven (77%) developed bacterial pneumonia. All patients were weaned from ECLS. Six patients (67%) survived to hospital discharge. Cause of death was multiple organ failure in two patients; one died from respiratory failure. V-V ECLS is a useful alternative to open sternotomy for ventilatory induced hemodynamic compromise post cardiotomy, especially in patients with LVADs. PMID- 9360081 TI - Portable cardiopulmonary support system as a bridge to left ventricular assist system implantation. A new strategy for the treatment of end stage cardiac disease. AB - The key to the successful implantation of a left ventricular assist system (LVAS) for patients with end stage cardiac disease is whether the functions of other vital organs are irreversibly damaged or not. The portable cardiopulmonary support system (PCPS) is not only as convenient as, but is more powerful than, the intra-aortic balloon pump (IABP) in resuscitating impaired end organ function. To investigate the efficacy of PCPS in end stage cardiac disease, end organ function before and after the application of PCPS was retrospectively analyzed for end stage cardiac disease. From 1992 to 1996, five cardiomyopathy patients with deterioration in end organ function, despite application of IABP, underwent PCPS support before implantation of LVAS. Urine volume and levels of liver enzymes (sAST and sALT) and serum creatinine were determined before and after institution of PCPS. After the start of PCPS, the urine output increased significantly (1,840 +/- 450-4,340 +/- 470 ml/day, p < 0.01), and levels of sAST, sALT, and serum creatinine decreased significantly (630 +/- 220-150 +/- 50 IU/L, 630 +/- 260-260 +/- 130 IU/L, and 2.9 +/- 0.5-1.2 +/- 0.1 mg/dl, respectively; p < 0.05). All five patients were successfully bridged to LVAS implantation, and none died of multiple organ failure caused by pre-existing cardiac failure. These results indicate that PCPS before LVAS implantation is useful in resuscitating impaired end organ function and improving the survival rate with LVAS implantation for end stage cardiac disease. PMID- 9360082 TI - Hepatic sinusoid endothelial dysfunction plays a role in hyperbilirubinemia in patients following implantation of an LVAD. AB - To clarify the mechanism of hyperbilirubinemia in the setting of a left ventricular assist device (LVAD), the change in hepatocellular function, hepatic sinusoid endothelial microcirculation, and inflammatory response before and after LVAD implantation were evaluated. Eight consecutive patients underwent the placement of an LVAD, and serum levels of total bilirubin (TB), transaminases [alanine transaminase (ALT), aspartate transaminase (AST)], interleukin (IL-6, IL 8), and hyaluronic acid (HA), an indicator of hepatic sinusoidal circulation, were measured before and after LVAD implantation. The TB of all patients increased significantly in the first post operative week (p < 0.05 vs. pre operatively). In five patients, the elevated TB (4.6 +/- 4.1 mg/dl) returned to pre-operative levels (2.7 +/- 2.0 mg/dl) by the 14th post operative day (Group R), but in the other three patients who died of multiple organ failure, the level of TB increased to 39.9 +/- 16.4 mg/dl (Group A). Levels of HA and IL-8 had good correlation with the level of TB (HA: r = 0.60, p < 0.05; IL-8: r = 0.55, p < 0.05). However, AST, ALT, and IL-6 were not related to changes in TB. These results suggest that hepatic sinusoid endothelial dysfunction and inflammatory reaction may play a significant role in hepatic failure in patients following implantation of an LVAD. PMID- 9360083 TI - A thromboxane A2 synthetase inhibitor as an anticoagulant for left ventricular assist devices. AB - A comparative study to establish more adequate anticoagulation therapy for left ventricular assist devices was done by administering various anticoagulants: heparin, argatroban (a pure thrombin inhibitor), a thromboxane A2 synthetase inhibitor, and protease inhibitor. Results of the investigation revealed that use of no anticoagulation activates the intrinsic pathway of blood coagulation and causes severe coagulopathy, heparin or argatroban causes bleeding tendency, and a thromboxane A2 synthetase inhibitor can maintain blood coagulation within the acceptable range, but not completely. Combined administration of a thromboxane A2 synthetase inhibitor and protease inhibitor was found to be the best anticoagulation therapy in this study. PMID- 9360084 TI - Intravascular gas transfer. Membrane surface area and sweeping gas flows are of prime importance. AB - Single and double hollow fiber intravascular gas exchangers were evaluated in an extracorporeal veno-venous bypass circuit (right atrium to pulmonary artery) including a tubular blood chamber (mimicking caval veins with an inner diameter of 26 mm) for evaluation of the membrane surface area/host vessel diameter gas transfer relationships. Six bovine experiments (body wt: 68 +/- 4 kg) with staged ex vivo blood flows of 1, 2, 3, and 4 L/min and a device oxygen inflow of 0, 3, and 6 L/min (0 or 3 L/min/device) were performed. Total oxygen transfer at a blood flow of 1 L/min was 33 +/- 4 ml/ min for a gas flow of 3 L/min (one device) vs 60 +/- 25 ml/ min for a gas flow of 6 L/min (two devices); at a blood flow of 2 L/min, the corresponding oxygen transfer was 46 +/- 16 ml/min for a gas flow of 3 L/min vs 95 +/- 44 ml/min for a gas flow of 6 L/min; at a blood flow of 3 L/min, the corresponding oxygen transfer was 48 +/- 24 ml/min for a gas flow of 3 L/ min vs 92 +/- 37 ml/min for a gas flow of 6 L/min (p < 0.01 for comparison of areas under the curves). Total carbon dioxide transfer at a blood flow of 1 L/min was 47 +/- 18 ml/min for a gas flow of 3 L/min vs 104 +/- 26 ml/min for a gas flow of 6 L/min; at a blood flow of 2 L/min, the corresponding carbon dioxide transfer was 59 +/- 19 ml/min for a gas flow of 3 L/ min vs 129 +/- 39 ml/min for a gas flow of 6 L/min; at a blood flow of 3 L/min, the corresponding carbon dioxide transfer was 60 +/- 22 ml/min for a gas flow of 3 L/min vs 116 +/- 49 ml/min for a gas flow of 6 L/min (p < 0.01). For the given setup, the blood flow/gas transfer relationship is non linear, and a plateau is achieved at a blood flow of 2.5 L/min for O2 and CO2. Doubling membrane surface area and consecutively sweeping gas flows result in doubling of gas transfers at all tested blood flows. However, increased membrane surface area and blood flow produce a higher pressure drop that in turn limits the fiber density that can be used clinically. PMID- 9360085 TI - Doppler velocimetry in cavitating media. AB - A numerical model has been developed to simulate propagation of ultrasonic beams in inhomogeneous moving media. The model is based on the ray theory of propagating waves, valid in the limit of high frequencies. The resulting equations depend only on local values of the velocity field and the speed of sound. In its implementation, the model assumes that the interactions of sound with the surrounding flow field are decoupled. This allows for applying the model in a post processing mode to flows computed by other means. The model was used to investigate beam behavior in unsteady cavitating flows. The study was motivated by reports of cavitation occurring in mitral bi-leaflet mechanical heart valves. The flow field and cavitation physics were simulated using a general purpose computer code, CFD-ACE. The ultrasonic beam model was then used to calculate the beam path, orientation, and frequency changes in the transient cavitating region. Results show that the presence of cavitation can fundamentally alter the beam propagation characteristics. Simple models that assume rectilinear propagation cannot, by definition, handle such flows. Cavitation incurs very large variations in the local sound speed, which in turn can induce very large distortions in the beam. This fact has strong ramifications regarding the accuracy of ultrasonic velocimetry when simple models are used to interpret Doppler data gathered under such flow conditions. PMID- 9360086 TI - Use of three-dimensional sonomicrometry to study the motion of the mitral valve. AB - To develop an anatomically correct mitral valve prosthesis, one needs to study the dynamics of the mitral valve apparatus in vivo. The authors used three dimensional (3D) sonomicrometry and custom visualization software to develop a system to study the mitral valve. Sixteen ultrasonic transducers each were implanted into the hearts of pigs under cardiopulmonary bypass. Four of these crystals were affixed to the base and apex of both papillary muscles, four were attached to the free edge of the anterior and posterior leaflets where the main chordae attach, six were placed around the mitral annulus, and two were affixed to the epicardial wall. The digital sonomicrometer system sequentially fired each transducer and listened for an ultrasound signal at the other 15. This process was repeated so that all 16 transducers were sequentially fired, and each cycle of 16 was repeated 200 times/sec. The matrix of distances obtained between all the combinations of pairs of the 16 transducers was converted to x, y, z coordinates, the shape of the mitral valve apparatus was reconstructed in 3D on a graphics computer, and the valve's motion was analyzed over several cardiac cycles. The authors conclude that mapping of the mitral valve apparatus in pigs by 3D sonomicrometry provides quantitative measurements that can aid in the design of a mitral valve prosthesis that closely replicates the anatomy and function of the natural valve. PMID- 9360088 TI - Silver modification of polyethylene terephthalate textiles for antimicrobial protection. AB - The safety and in vitro effectiveness of applying silver to polyethylene terephthalate fabric mechanical heart valve (MHV) sewing cuffs for the prevention of prosthetic valve endocarditis (PVE) were evaluated. PVE is an infrequent but grave complication of cardiac surgery associated with mortality rates potentially exceeding 50%. A poor response to antibiotic therapy is partly responsible for the high mortality rates. Silver is a well known antimicrobial agent with broad effectiveness. Preliminary in vitro microbial challenge studies of the coated fabric using the New York State 63 bacteriostatic test and Dow Corning Shake Flask test showed a > or = 97% reduction for most organisms tested. Sheep mitral valve replacement studies suggest comparable tissue ingrowth of uncoated and coated fabric with a more organized, thinner pannus formed on silver coated fabric. Low levels of silver were present in the serum at all time periods. These results indicate MHVs with silver coated cuffs may provide additional protection against PVE. PMID- 9360087 TI - Porcine aortic wall flexibility. Fresh vs Denacol fixed vs glutaraldehyde fixed. AB - It has been postulated that, in theory, stentless bioprosthetic heart valves provide improved hemodynamics and durability over their stented counterparts. A number of glutaraldehyde modified porcine stentless valves are currently either on the market or in clinical trials. Polyepoxy compound as an alternative cross linking reagent to glutaraldehyde for bioprostheses has been reported to mitigate calcification. The present study was to investigate the effect of the fixation methods on porcine aortic wall flexibility. Ring specimens were selected from three groups of porcine roots: fresh, low pressure glutaraldehyde fixed, and low pressure Denacol (polyepoxy compound) fixed. Pulled between two rods on a tensile tester, a ring specimen's load-deformation relationship was recorded and analyzed to numerically compute the tissue modulus at low strains. The results showed that the Young's moduli were 0.113 +/- 0.036, 0.494 +/- 0.113, and 1.320 +/- 0.292 MPa (mean +/- SD, n = 10) for the fresh, Denacol fixed, and glutaraldehyde fixed aortic walls, respectively. The Denacol fixed aortic wall was more flexible than the glutaraldehyde fixed one. It was also found that the Denacol fixed aortic wall maintained most of the natural residual strains, while the glutaraldehyde fixed aortic wall did not. PMID- 9360089 TI - Error associated with the choice of an aortic cannula in measuring regional cerebral blood flow with microspheres during pulsatile CPB in a neonatal piglet model. AB - The effectiveness of an infant pulsatile cardiopulmonary bypass (CPB) system on maintaining regional cerebral blood flow (CBF) using two different types of aortic cannulae in 3 kg piglets has been investigated. The University of Texas Neonatal Pulsatile Pump was used with either a DLP (Group I, n = 6) or an Elecath (Group II, n = 7) 10Fr aortic cannula. In all the subjects, nasopharyngeal temperature was reduced to 18 degrees C, followed by 1 hr of deep hypothermic circulatory arrest (DHCA), then 45 min of rewarming. During cooling and rewarming, alpha-stat blood gas management was used. The radionuclide labeled microsphere technique was used to determine blood flows in the cerebellum, basal ganglia, brainstem, right and left hemispheres, as well as global CBF (ml/100 g/min). When the DLP aortic cannula was used, regional and global CBF appeared to be higher pre- and post DHCA. In both groups regional CBF was significantly decreased following DHCA. Although better pulsatile flow was attained using the DLP cannula and this may have resulted in higher regional CBF, these results must be interpreted in light of the large standard deviations noted when this cannula was chosen for the studies. These results demonstrate the importance of choosing an appropriate aortic cannula for measuring regional CBF with a pulsatile neonate infant CPB system. PMID- 9360090 TI - Flow rate dependent ex vivo deheparinization with immobilized cationic ligand. AB - The Heparin Removal Device is a deheparinization system that provides a good alternative when adverse reaction to protamine is suspected or when a heparin coated device is employed for cardiopulmonary bypass. In a bovine model, after systemic heparinization with 300 IU/kg body wt, the authors investigated the rate of deheparinization using this plasmapheresis system that allows exposition of heparinized plasma to an immobilized cationic ligand. Blood was shunted through a heparin coated veno-venous circuit to the plasma separator at a flow rate of 500 ml/min (n = 3, body wt 68 +/- 4 kg) or 1,000 ml/min (n = 3, body wt 57 +/- 4 kg). All plasma separators remained patent without any failure of the devices. Blood samples were drawn at regular intervals for coagulation parameters. The evolution of the activated coagulation time (ACT) was measured during the first 60 min of the deheparinization procedure, and results were compared with spontaneous evolution in a control group (n = 3, body wt 73 +/- 5 kg) without reversal of heparinization. After heparin administration, mean ACT was longer than 1,000 sec in the three groups. Fifteen minutes later it was still > 1,000 sec in the control group, whereas it was 427 +/- 8 sec in the slow flow group (500 ml/min) and 340 +/- 26 sec in the high flow group (1,000 ml/min). At 30 min it was 1,000, 367 +/- 26, and 200 +/- 24 sec, respectively, in the three groups. A regression curve was calculated for each group, and areas under the curves were compared. Ex vivo deheparinization was efficient in normalization of ACT, but removal of heparin appeared to be flow rate dependent. Increased blood flow from 500 to 1,000 ml/min across the deheparinization system resulted in significant acceleration of ACT normalization (p < 0.05). PMID- 9360091 TI - Development of a novel polyimide hollow fiber for an intravascular oxygenator. AB - The authors have synthesized a novel fluorinated polyimide to develop a membrane material for oxygenators and fabricated polyimide hollow fibers for use in an intravascular oxygenator. A dry/wet phase inversion process has been applied to a spinning process to prepare an asymmetric polyimide hollow fiber. The outer surface of the hollow fiber consists of an ultrathin, dense skin layer, with a calculated apparent thickness of approximately 60 nm. The fiber diameter was 800 microns with a wall thickness of 130 microns. The asymmetric hollow fiber has two advantages because (a) the hollow fiber does not produce plasma leakage due to the dense skin layer of the surface and (b) O2 and CO2 transfer rates through the hollow fiber are enhanced due to the ultrathin skin layer and are significantly larger than those of presently available membrane oxygenators. The blood compatibility of the polyimide hollow fiber without heparinization has been evaluated in vitro. Deformation and aggregation of platelets adherent to the fibers were not observed, and the polyimide suppressed platelet activation. The polyimide significantly reduced the production of anaphylatoxin and also suppressed complement activation. PMID- 9360092 TI - Hemodynamic and humoral conditions in stepwise reduction of pulmonary blood flow during venoarterial bypass in awake goats. AB - The effects of reduced pulmonary arterial blood flow (PAF) during venoarterial bypass (VAB) on hemodynamic and humoral conditions were investigated in a series of experiments in a chronic animal model. A biventricular bypass system was installed in five adult goats weighing 49.8 +/- 1.1 kg. Two weeks later, the extracorporeal circuitry was changed to VAB without anesthesia. The PAF was reduced stepwise from 100% to 50, 25, 10, and 0% of total systemic flow. The mean aortic pressure and systemic vascular resistance decreased from 110 +/- 14 to 66 +/- 3 mmHg and from 1,288 +/- 77 to 740 +/- 73 dyne.sec/cm5, respectively, in proportion to the decrease in PAF from 100 to 0%. The prostaglandin E2 concentration increased from 1.5 +/- 0.6 to 8.8 +/- 0.6 pg/ml following the decrease in PAF from 100 to 0%. The renin-angiotensin system increased in proportion to the decrease in PAF. In contrast, the epinephrine and norepinephrine concentrations (60 +/- 10 and 227 +/- 80 pg/ml, respectively, at 100% PAF) did not change appreciably even at 10% PAF, but were markedly elevated to 335 +/- 117 and 2,088 +/- 1,503 pg/ml at 0% PAF. The antidiuretic hormone level similarly changed. In conclusion, decrease in PAF during VAB exerts significant effects on hemodynamics in a proportional manner and on vasoactive humoral factors in a diverse manner. PMID- 9360093 TI - Comparative blood compatibility of polyether vs polycarbonate urethanes by epifluorescent video microscopy. AB - The segmented polyether urethanes (PEUs) have been used in implantable medical devices due to excellent mechanical properties, acceptable blood compatibility, and good biostability. However, recent studies demonstrate that the polyether soft segment of PEU is susceptible to oxidative degradation in vivo due to scission of the polyether group. Recently, polycarbonate urethanes (PCUs) having no ether linkage in the soft segment have been developed, and show improved stability against oxidative degradation over PEUs. The current study evaluates blood compatibility of these PCUs in comparison with PEUs using epifluorescent video microscopy (EVM) combined with a parallel plate flow cell. The authors selected two PCUs, Corethane 80A (Corvita Corporation, Miami, FL) and PCU(1560), and two PEUs, Pellethene 2363-80AE (Dow Chemical Japan, Tokyo, Japan) and Tecoflex EG80A (Thermedics, Inc., Woburn, MA), all of which have similar hard segment compositions (MDI or HMDI:1,4-butanediol(BD)) and the same hardness of 80A. The EVM measured the amount of platelet coverage on the surfaces using human whole blood perfused at a wall shear rate of 100/sec for 20 min. Complement activation (C3a) also was measured. Both PEUs, especially Pellethane, showed significantly higher platelet adhesion than the PCUs (p < 0.05). There were no significant differences in platelet adhesion between the two PCUs. As for C3a measurements, Tecoflex showed higher complement activation than the others. Based on these results, it is recommended that PEUs should be replaced by ether free PCUs for use in implantable blood contacting devices such as artificial hearts and pacemaker lead insulators. PMID- 9360094 TI - Development of a glucose sensor with on/off control of enzyme activity without the effects of protein adsorption. AB - The main factor mitigating against the realization of a hypodermically inserted glucose sensor for an artificial pancreas is the change in response current due to fibroblast adhesion and protein adsorption to the sensor surface. To overcome this problem, we have developed a method whereby the activity of glucose oxidase (GOD) fixed on the membrane of the sensor surface is switched on and off, and measurements are made during a transient state in which the glucose concentration gradient within the GOD membrane is small. Measuring in a transient state while GOD activity is being controlled, a correlation was observed between glucose concentration and response current in a phosphate buffer solution. Calibration curves of response current against glucose concentration in aqueous solutions of human serum albumin and in phosphate buffer solution were then compared using the transient method and a steady state method without control of GOD activity. In addition, glucose concentration was measured in bovine plasma for 480 min, and the time courses of the response currents for the transient and steady state measurements were compared. It was found that in both experiments the response current decreased greatly under steady state measurement as a result of protein adsorption, but during the transient measurement, response current was virtually unchanged. By measuring glucose concentration in the transient state while controlling GOD activity, it is possible to inhibit the effects of protein adsorption. PMID- 9360095 TI - Electrical isolation of the heart. Stabilizing parallel conductance for left ventricular volume measurement. AB - Modern indices of left ventricular function require accurate measurement of left ventricular volume (LVV). Although conductance catheter (COND) measurements of LVV have been found to be reproducible under steady state conditions in closed chest animals, after median sternotomy, measurements of LVV are subject to exaggerated variation in parallel conductance (alpha Vc) outside of the left ventricle. Current calibration methods for measuring alpha Vc include hypertonic saline injection and quantitative two dimensional echocardiography. Unfortunately, these methods are hampered by imprecision, since frequent changes in alpha Vc in the open chest make recalibration impractical. Accordingly, a latex wrap technique was developed to insulate the left ventricle from extracardiac sources of alpha Vc in the open chest. Anesthetized pigs (n = 5) underwent a median sternotomy with insertion of a 6 French COND-micromanometer combination catheter into the left ventricle. Three conditions were tested: 1) unaltered; 2) metallic retractor outside of the pericardium (metal); and 3) latex wrap between the metal and pericardium. Pressure/COND loops showed that the insulator improved the shape of the loops and decreased alpha Vc, as measured by an echo-area/COND relationship, whereas metal increased alpha Vc and produced artifacts in the loops. In conclusion, electrical isolation eliminates distortion of pressure/COND loops related to extracardiac sources of alpha Vc, therefore allowing for accurate COND measurements in the open chest. PMID- 9360096 TI - Eight years of clinical endothelial cell transplantation. Closing the gap between prosthetic grafts and vein grafts. AB - After years of in vitro studies and non human primate implantations, the authors commenced their clinical program of autologous in vitro endothelialization of polytetrafluoroethylene (ePTFE) grafts in 1989. Based on the successful 3 year results of a pilot study (Phase I) with 49 patients (1:2 randomization, assigning 33 patients to the endothelialized group and 16 to the control group), the authors offered in vitro endothelialized grafts to all patients who did not have a suitable saphenous vein available from June 1993 onward (Phase II). Another 72 patients received 81 successfully endothelialized ePTFE grafts in this second phase of the transplantation program. In the Phase I randomized trial, the Kaplan Meier survivorship analysis showed a primary 3 year patency rate of 84.7% for endothelialized grafts and 55.4% for control grafts. After 5 years, it was 73.8% for the endothelialized group and 20.8% for the controls. At the end of the 7 year follow-up period, the primary patency rate for endothelialized grafts remained high at 73.8%, whereas that for the control grafts dropped to zero (log rank test; p = 0.001 and Wilcoxon test; p = 0.003). The subsequent Phase II routine clinical implantation of endothelialized ePTFE grafts showed a 3 1/2 year primary patency rate of 72.9% for all femoropopliteal reconstructions. The authors' overall 7 year follow-up with endothelialized femoropopliteal ePTFE grafts (n = 108) shows a patency of 66.0%. When pretreated with fibronectin (n = 43), the 7 year patency was 72.1%. In the above-knee group, the 7 year patency for fibronectin treated grafts was as high as 75.8% (n = 36). After 8 years of clinical endothelial cell transplantation, the authors conclude that in vitro endothelialization of ePTFE grafts results in a patency rate of arterial prostheses comparable with that of vein grafts. PMID- 9360097 TI - Successful small diameter arterial grafting using cryopreserved allograft arteries. AB - Intimal hyperplasia (IH) limits the long-term success of veins as arterial grafts. IH occurs in veins partly as an adaptive process to arterial pressure conditions. The authors have previously reported early success with cryopreserved (CP) saphenous veins as aortocoronary bypass grafts, and they have hypothesized that CP arterial segments were already structurally adapted for arterial conditions. Six femoral arterial segments were harvested from three adult donor dogs, and cryopreserved. The segments were thawed and implanted into six recipient dogs, in end-to-end fashion, as interpositional grafts in the femoral artery. A similar length of native femoral artery was removed from the implant site and grafted in the contralateral femoral artery of the same animal to serve as native autograft-matched controls. Grafts were harvested bilaterally after 2 (n = 3) and 4 weeks (n = 3), perfusion fixed (80 mmHg, 15 min), and analyzed histologically. All grafts were patent at harvest, and flows distal to the grafted segments were not significantly different between grafts within an animal either at implant or subsequent harvest. Although CP arterial grafts still showed slight but significant dilation compared with native autograft, the dilation was much less than seen previously with either CP or native venous segments. No evidence of inflammation or IH was seen in CP arterial grafts. The absence of early IH or inflammation suggests that CP small diameter arteries may perform better than many currently available allograft tissues and synthetic prosthetics. PMID- 9360098 TI - Selective anticoagulation with active site blocked factor IXa in synthetic patch vascular repair results in decreased blood loss and operative time. AB - Heparin has been the mainstay of anti thrombic therapy in arterial repair procedures. With increasing use of synthetic patch angioplasty (polytetrafluoroethylene [PTFE] or Dacron, Medical Products, Flagstaff, AZ) to improve long-term patency and limit aneurysmal dilation, however, the use of heparin has been associated with excessive needle hole bleeding, resulting in time delay in the operating room to achieve hemostasis, as well as clinically significant blood loss. Because of the multiple sites of action of heparin in the coagulation cascade, both intravascular (desired effect) and extravascular (untoward side effect) hemostasis are impaired. The authors therefore tested the hypothesis that selective inhibition of intravascular coagulation, without significant impairment of extravascular hemostasis, would prevent clotting intraluminally while preserving hemostasis at the suture line of the patch graft. The unique position of factor IX/IXa in the coagulation cascade renders its inhibition an ideal target in this setting. The authors prepared active site blocked factor IXa (IXai) using dansyl-Glu-Gly-Arg chloromethylketone, and tested this hypothesis in a New Zealand rabbit aortotomy model with PTFE patch closure using either heparin (25 i.u./kg; n = 16) or IXai (300 micrograms/kg; n = 21). The infrarenal aorta was identified and isolated, the anti coagulant infused, aortic cross clamp placed, and aortotomy repaired with a 2 x 6 mm PTFE patch. After cross-clamp removal, blood loss was measured and time to hemostasis was recorded. Compared with heparin, IXai resulted in significantly reduce blood loss (6.97 +/- 4.4 g vs 2.72 +/- 2.51 g, respectively, p < 0.008), and time to hemostasis (2.94 +/- 0.77 min vs 2.0 +/- 0.63 min, respectively, p < 0.003). To assess long-term patency and thrombosis, 12 rabbits (given heparin; n = 6 and IXai; n = 6) were observed for up to 2 months post-operatively. No differences were observed between rabbits treated with heparin or IXai; 100% of the grafts were patent with no differences in degree of intimal hyperplasia by histologic analysis. Together, these data suggest that use of IXai in PTFE vascular repair will safely allow realization of the benefits of long-term patency and decreased aneurysmal dilatation, while eliminating the intraoperative morbidity of needle hole bleeding. PMID- 9360099 TI - Vascular endothelial growth factor enhances vascularization in microporous small caliber polyurethane grafts. AB - Neoarterial regeneration in an implanted small caliber vascular prosthesis is complexly controlled by many structural and biologic factors, such as cytokines. The authors designed an artificial graft, which was prepared as follows. Segmented polyurethane tubular film (inner diameter, 1.5 mm; wall thickness, 100 microns; length, 20 mm), in which micropores (pore size, 100 microns) were fabricated by an excimer laser ablation technique, were coated with a mixed solution of photoreactive gelatin and heparin with or without cytokines (vascular endothelial growth factor [VEGF]: 5 or 50 micrograms/ml, basic fibroblast growth factor [bFGF]: 1 microgram/ml). These coated grafts were irradiated by ultraviolet light, and were implanted in aortas of rats for 4 weeks; the VEGF (5 micrograms/ml) group, n = 6; the bFGF group, n = 6; the VEGF (5 micrograms/ml)/bFGF group, n = 11; the VEGF (50 micrograms/ml)/bFGF group, n = 5; and the control group, n = 9. Control grafts were treated without cytokines. Endothelial coverage was greater for the cytokine immobilized groups (approximately equal to 50-60%) than for the control group (approximately equal to 30%). At the midportion of the triple VEGF immobilized group, many capillaries were seen in the neoarterial intima, and in the micropores, although such capillaries were rarely observed in the bFGF and control groups. Thus, impregnation of VEGF in the gelatinous layer of grafts enhanced transanastomotic tissue ingrowth and transmural capillary ingrowth. PMID- 9360100 TI - Recombinant human erythropoietin resistance in hemodialysis. Effects of paired filtration dialysis. AB - A percentage of hemodialysis (HD) patients are resistant to recombinant human erythropoietin (rHuEPO), a phenomenon that occurs less frequently in patients dialyzed with biocompatible membranes (M) and in peritoneal dialysis. The authors evaluated the effects of paired filtration dialysis (PFD)--a dialysis technique based on the use of an emophan M in conjunction with a polysulphone M--on erythropoiesis in HD patients resistant to rHuEPO. Twelve HD patients with anemia resistant to long-term therapy with rHuEPO (200.24 U/kg body weight three times per week intravenously for 10.2 months) were studied. Patients had been treated for an average of 46.9 months with bicarbonate HD, using cuprophan M (Phase A) and, successively, for 12 months by PFD (Phase B). The following parameters were evaluated monthly: 1) hemoglobin and hematocrit values; 2) serum levels of erythropoietin (EPO); and 3) serum levels of interleukin (IL)-3, IL-6, IL-10, IL 1 beta, tumor necrosis factor alpha (TNF-alpha), and interferon gamma (IFN gamma). At the end of Phase A and Phase B, patients underwent bone marrow biopsies to evaluate 1) bone marrow burst forming unit erythroid (BFU-E) and colony forming unit erythroid (CFU-E) proliferative capacity, and 2) bone marrow mononuclear cell EPO-receptor (EPO-R) number. During Phase B, there was a progressive rise in hematocrit and hemoglobin values, so that within the sixth month, the rHuEPO dose was reduced to 80 +/- 15 U/kg body weight three times per week. At the same time, an increase in serum IL-3, IL-6, and IL-10 levels was seen, whereas serum IL-1 beta, TNF-alpha, and IFN-gamma levels decreased. This was accompanied by a rise in BFU-E and CFU-E growth and in bone marrow mononuclear cell EPO-R number. During Phase B, after the dialysis session, serum EPO levels increased by about 30% in comparison with pre dialysis values, whereas during Phase A they decreased by about 14%. In HD patients, EPO resistance may caused either by absorption of rHuEPO to the cuprophan M, or an increased release of cytokines that inhibit erythropoiesis, such as IL-1 beta, TNF-alpha, and IFN gamma, and to a decrease in stimulatory cytokines such as IL-3, IL-6, and IL-10. These negative phenomena are reversed by the use of biocompatible dialysis techniques such as PFD. PMID- 9360101 TI - Detecting vascular access dysfunction. AB - Access flow (QACC) is a major determinant of patency. Access recirculation (AR > 2%), normalized venous intra-access pressure (vPIA/MAP), and QACC are used to detect access dysfunction. We compared these three measures of access function (ultrasound dilution to measure AR and QACC). A total of 779 measurements were performed on 58 arteriovenous fistulas (AVFs) and 114 polytetrafluoroethylene (PTFE) grafts (1-8/access) over 13 months, and the access parameters at the beginning of each period were related to access events within that period. Pump blood flow averaged > 420 ml/min. AR occurred uncommonly (3.8%), and in half the cases, resulted from technical error by staff. In accesses that thrombosed or underwent intervention for stenosis, AR was present in only 3 of 11 AVFs and 8 of 57 PTFE accesses. When AR was present in grafts, QACC averaged 270 +/- 23, and access thrombosis followed unless intervention occurred. In grafts, vPIA/MAP averaged 0.34 +/- 0.01 in those remaining patent, 0.52 +/- 0.08 in those that had undergone intervention, and 0.54 +/- 0.04 in those that had thrombosed. QACC averaged 1,121 +/- 26, 605 +/- 45, and 550 +/- 65 ml/min, respectively, in the three groups. By contrast, QACC differed significantly in patent AVFs (1,053 +/- 35) compared with failing AVFs (363 +/- 48), but vPIA/MAP did not. AR is thus a late manifestation of access failure. QACC is the best diagnostic test of access dysfunction in AVFs. Interpretation of vPIA/MAP in grafts is enhanced by periodic QACC measurements. PMID- 9360102 TI - Detection of access strictures and outlet stenoses in vascular accesses. Which test is best? AB - The location of stenoses within an access may influence the diagnostic value of access monitoring tests. Whereas decreasing access flow (QACC) should occur with both venous outlet stenoses and strictures within the body of the access, normalized intra-access venous pressure (vPIA/MAP) depends on location of the venous needle relative to the lesion. The authors determined the value of vPIA/MAP and direct measurement of percent access recirculation (AR) and QACC in detecting venous outlet stenoses and strictures. Abnormal access studies were evaluated by Doppler ultrasound and fistulography. Well functioning grafts and arteriovenous fistulas (AVFs) have no AR; QACC averages 1,101 +/- 26 and 1,073 +/ 35 mL/min, and vPIA/MAP ratios are 0.34 and 0.16, respectively. Venous outlet stenoses (n = 36) or strictures (n = 32) were detected before thrombosis or intervention in 172 vascular accesses at risk. QACC in accesses with stricture was significantly lower than in those with venous outlet stenosis (361 +/- 11 vs 526 +/- 43 ml/min), as was less than prescribed blood flow (423 +/- 7 ml/min). AR was not detected in any access with stricture and in only 4 of 36 accesses with outlet stenosis. vPIA/MAP was elevated with venous outlet stenosis but not with strictures. The findings of QACC being less than blood pump flow without AR by dilution methods differentiated strictures from venous outlet stenoses. PMID- 9360103 TI - More than 1 year continuous operation of a centrifugal pump with a magnetically suspended impeller. AB - The authors have been developing a centrifugal pump with a magnetically suspended impeller (MSCP) designed for total artificial heart and long-term ventricular support. The MSCP consists of a magnetic bearing, an impeller and housing, and a driving motor. The impeller is suspended by a magnetic bearing, therefore providing contact free rotation of the impeller inside the pump. This study was designed to evaluate long-term durability and nonthrombogenicity of the MSCP in a chronic sheep model. The blood contacting surfaces of the pump and conduits were completely modified by a heparin immobilization technique (Hepaface). The MSCP was placed paracorporeally as a left heart bypass between left ventricle and descending aorta in three adult sheep. Coumadin was given orally to maintain prothrombin time at 15-20 sec. The coagulation and hematologic parameters, including plasma free hemoglobin, were periodically monitored throughout the experiment. Under daily movement in the cage, the pump could produce average flow rates of 3-6 L/min (50-100 ml/kg) at 1,700-2,000 rpm. Although the arterial pulse contour decreased, there was no physiologic deterioration. The axial impeller excursion monitored by a position sensor was < 25 microns. Plasma free hemoglobin level remained at < 5 mg/dl throughout the experiment. There was no increase in the motor current, which indicates no massive thrombus formation around the impeller. One experiment was terminated at 70 days due to Hall sensor dysfunction of the motor. The retrieved pump was entirely free from thrombus formation. There was no detectable thrombus formation inside the pump or the inflow and outflow conduits. Hematologic, renal, and hepatic parameters remained within the normal range throughout the experiment. The other two sheep have survived for more than 395 and 41 days without major complication. These studies demonstrated that the MSCP has significant potential for long-term use. PMID- 9360104 TI - Control of the pressure flow relationship with a magnetically suspended centrifugal pump in a chronic animal experiment. AB - A magnetically suspended centrifugal pump (MSCP) has been developed for long-term ventricular support. Effective torque to blood of the MSCP is exactly proportional to a motor current because of no friction inside the MSCP. The authors have devised new driving modes using these characteristics and applied it to a chronic animal experiment. Three driving modes were compared: 1) a constant rotational speed (N), 2) a constant motor current (I), and 3) a controlled motor current (CI). In two of nine sheep, the MSCPs were operated by the N and in seven by the I mode. The motor current and the rotational speed were always monitored. The CI mode was studied by altering the resistance of the vessels. In the I mode, the rotational speed varied depending upon the pressure head, and the slope of the pressure-flow (P-Q) relationship was steeper than that of the N mode, so that the pump flow was stabilized. In the CI mode, in which the motor current increased to compensate for the decrease in pump flow as the rotational speed increased, the P-Q slope was effectively controlled when the resistance was changed. The MSCP was able to control the P-Q slope without monitor of the pump flow. Various driving modes could be selected according to changes in resistance. PMID- 9360105 TI - The analysis, design, and testing of a blood lubricated hydrodynamic journal bearing. AB - The Cleveland Clinic Foundation's Innovative Ventricular Assist System (IVAS) uses a hydrodynamic journal bearing to support the rotating assembly of the blood pump. Bearing dimensions are chosen so that a stable film of lubricant develops and separates stationary and rotating pump surfaces during operation. This bearing type provides several advantages for a permanently implanted device, including essentially no wear for very long life and very high reliability, as well as a self pumping action that generates circumferential wash flow and thus lowers the risk of bearing associated deposition. However, these advantages are accompanied by design issues not encountered with typical journal bearing, such as low shear stress, bearing ends that are not at atmospheric pressure, and low radial bearing loads. To address these issues, several concepts for a hydrodynamic blood bearing were designed and analyzed using a special computer code to perform parametric studies. This design analysis code was developed to define optimum bearing performance under selected load and speed ranges and within practical tolerances. Results showed the range of dimensions and conditions over which an effective, reliable, blood lubricated journal bearing can be designed. Subsequent bench testing has validated the theoretical conclusions and shown this bearing type to be very robust in a blood pump application. PMID- 9360106 TI - Analysis of a new PM motor design for a rotary dynamic blood Pump. AB - The permanent magnet (PM) motor for a rotary dynamic blood pump requires high power density to coordinate the motor size with the limited pump space and high efficiency to reduce the size and weight of the associated batteries. The motor also serves as a passive axial magnetic thrust bearing, a reacting hydraulic force, and provides a stabilizing force for the radial journal bearing. This article presents analysis of a new PM motor for the blood pump application. High power density is achieved by using the Halbach magnetic array, and high efficiency is accomplished by optimizing the rotor magnet assembly and the stator slots/windings. While both radial and axial forces are greatly enhanced, pulsating components of the torque and force are also significantly reduced. PMID- 9360107 TI - Continued development of the Nimbus/University of Pittsburgh (UOP) axial flow left ventricular assist system. AB - Nimbus and the University of Pittsburgh (UOP) have continued the development of a totally implanted axial flow blood pump under the National Institutes of Health (NIH) Innovative Ventricular Assist System (IVAS) program. This 62 cc device has an overall length of 84 mm and an outer diameter of 34.5 mm. The inner diameter of the blood pump is 12 mm. It is being designed to be a totally implanted permanent device. A key achievement during the past year was the completion of the Model 2 pump design. Ten of these pumps have been fabricated and are being used to conduct in vitro and in vivo experiments to evaluate the performance of different materials and hydraulic components. Efforts for optimizing the closed loop speed control have continued using mathematical modeling, computer simulations, and in vitro and in vivo testing. New hydraulic blade designs have been tested using computational fluid dynamics (CFD) and flow visualization. A second generation motor was designed with improved efficiency. To support the new motor, a new motor controller fabricated as a surface mount PC board has been completed. The program is now operating under a formal QA system. PMID- 9360108 TI - The cool seal system: a practical solution to the shaft seal problem and heat related complications with implantable rotary blood pumps. AB - A critical issue facing the development of an implantable, rotary blood pump is the maintenance of an effective seal at the rotating shaft. Mechanical seals are the most versatile type of seal in wide industrial applications. However, in a rotary blood pump, typical seal life is much shorter than required for chronic support. Seal failure is related to adhesion and aggregation of heat denatured blood proteins that diffuse into the lubricating film between seal faces. Among the blood proteins, fibrinogen plays an important role due to its strong propensity for adhesion and low transition temperature (approximately 50 degrees C). Once exposed to temperature exceeding 50 degrees C, fibrinogen molecules fuse together by multi-attachment between heat denatured D-domains. This quasi polymerized fibrin increases the frictional heat, which proliferates the process into seal failure. If the temperature of the seal faces is maintained well below 50 degrees C, a mechanical seal would not fail in blood. Based on this "Cool Seal" concept, we developed a miniature mechanical seal made of highly thermally conductive material (SiC), combined with a recirculating purge system. A large supply of purge fluid is recirculated behind the seal face to augment convective heat transfer to maintain the seal temperature below 40 degrees C. It also cools all heat generating pump parts (motor coil, bearing, seal). The purge consumption has been optimized to virtually nil (< 0.5 cc/day). An ultrafiltration unit integrated in the recirculating purge system continuously purifies and sterilizes the purge fluid for more than 5 months without filter change. The seal system has now been incorporated into our intraventricular axial flow blood pump (IVAP) and newly designed centrifugal pump. Ongoing in vivo evaluation of these systems has demonstrated good seal integrity for more than 160 days. The Cool-Seal system can be applied to any type of rotary blood pump (axial, diagonal, centrifugal, etc.) and offers a practical solution to the shaft seal problem and heat related complications, which currently limit the use of implantable rotary blood pumps. PMID- 9360109 TI - Plasma protective effect on red blood cells exposed to mechanical stress. AB - Hemodilution with plasma expanders is a widely applied practice during extracorporeal circulation and hemodialysis. Despite the immediate beneficial effects of hemodilution, such as reduction of blood viscosity and red blood cell (RBC) aggregation, elevation of blood flow in the microcirculation, etc., the dilution of plasma may cause some unfavorable effects on RBCs, amplifying the mechanical damage caused by circulatory assist devices. The authors investigated the effect of partial and total replacement of plasma on susceptibility of human and bovine RBCs to mechanical stress in vitro. Hemolysis was measured after the exposure of RBCs suspended in different media to similar mechanical stress. Experiments were performed at room temperature with control of osmolality and viscosity of the suspension media. The lowest hemolysis was obtained for RBCs suspended in serum, plasma, and albumin solutions. Hemolysis in PBS and Dextran suspensions was more than three times higher than that in plasma (p < 0.001). The protective effect depended upon protein concentration. Human RBCs were found to be significantly more sensitive to mechanical stress than bovine RBCs in all investigated suspension media (p < 0.005). Human RBCs from men suspended in plasma were found to be significantly (p < 0.05) more fragile than RBCs from women. The presence of even small amounts of plasma (such as 25%) in the suspension media significantly (p < 0.001) decreased hemolysis. However, a 30% replacement of plasma with PBS or Dextran solutions caused a statistically significant (p < 0.001) increase in mechanical hemolysis. This suggests that a decrease in the concentration of plasma proteins due to hemodilution may elevate blood damage during extracorporeal circulation and hemodialysis. PMID- 9360110 TI - Progress in the development of a transcutaneously powered axial flow blood pump ventricular assist system. AB - Development of the Jarvik 2000 intraventricular assist system for long-term support is ongoing. The system integrates the Jarvik 2000 axial flow blood pump with a microprocessor based automatic motor controller to provide response to physiologic demands. Nine devices have been evaluated in vivo (six completed, three ongoing) with durations in excess of 26 weeks. Instrumented experiments include implanted transit-time ultrasonic flow probes and dual micromanometer LV/AoP catheters. Treadmill exercise and heart pacing studies are performed to evaluate control system response to increased heart rates. Pharmacologically induced cardiac dysfunction studies are performed in awake and anesthetized calves to demonstrate control response to simulated heart failure conditions. No deleterious effects or events were encountered during any physiologic studies. No hematologic, renal, hepatic, or pulmonary complications have been encountered in any study. Plasma free hemoglobin levels of 7.0 +/- 5.1 mg/dl demonstrate no device related hemolysis throughout the duration of all studies. Pathologic analysis at explant showed no evidence of thromboembolic events. All pump surfaces were free of thrombus except for a minimal ring of fibrin, (approximately 1 mm) on the inflow bearing. Future developments for permanent implantation will include implanted physiologic control systems, implanted batteries, and transcutaneous energy and data transmission systems. PMID- 9360111 TI - In vivo and in vitro evaluation of the pulsatile mode of a magnetically suspended centrifugal pump. AB - The authors have been developing a magnetically suspended centrifugal pump (MSCP). They have devised a pulsatile mode for the MSCP, which was generated by altering rotational speed. This article describes in vitro and in vivo studies with the pulsatile mode of the MSCP. Hemolysis tests were performed in two identical circuits to compare the nonpulsatile (NP) mode and the pulsatile (P) mode. In vivo studies were performed in sheep. First, biventricular assisted circulation was instituted in the left heart with the MSCP and in the right heart with the Biopump. The native heart was induced to ventricular fibrillation. Second, a left ventricular assisted circulation was instituted as the native heart was beating. An inflow cannula was inserted into the left atrium in one sheep and into the left ventricle in the other. The normalized indices of hemolysis of the NP and P groups were 0.0025 +/- 0.0018 g/100 L, and 0.0032 +/- 0.0024 g/100 L (N = 4, not significant). During ventricular fibrillation in the P mode, the pulse pressure was 14 mmHg (the rotational speed: 1,500 to 2,600 rpm). In a beating heart, at atrial withdrawal, the pulse pressure increased from 10 to 24 mmHg (2,100 +/- 500 rpm), while at ventricular withdrawal, it decreased from 17 to 40 mmHg (2,000 +/- 500 rpm) on P mode. The MSCP in pulsatile mode did not increase hemolysis. At ventricular withdrawal, it was easier to produce a pulsation than at atrial withdrawal. The pulsatile mode of the MSCP is applicable to a left ventricular assist system. PMID- 9360112 TI - Heat from an implanted power source is mainly dissipated by blood perfusion. AB - Heat dissipation and its effects on tissue and blood interfaces are common problems associated with the development and increased use of artificial hearts, because all of the implantable actuators for artificial hearts generate waste heat due to inefficiencies of energy conversion. To determine the mechanisms of heat dissipation from artificial hearts, heated disks producing constant heat fluxes of 0.08 watts/cm2 were implanted adjacent to the left lung and the latissimus dorsi muscle in calves for 2 weeks, 4 weeks, and 7 weeks. At the end of each experiment, a series of acute studies was performed in which blood perfusion to the heated tissue was decreased or stopped to observe the contribution of blood perfusion to heat dissipation. The cooling effect of ventilation was also examined to determine its relative contribution to heat dissipation in lung tissue by decreasing the minute ventilation volume. The importance of blood perfusion for heat dissipation was demonstrated by the temperature rise after cessation of blood perfusion to the heated tissue. The contribution of ventilation to heat dissipation in the heated lung tissue was minimal. Contribution of total blood perfusion to heat dissipation was increased with time in the muscle tissue, which has relatively low resting blood perfusion, but not in the lung tissue, which has relatively high blood perfusion. In the heated muscle tissue, the in vivo adaptive response to chronic heat was functionally shown by the increased perfusion. In conclusion, blood perfusion was the main mechanism of heat dissipation from tissues that were adjacent to an implanted power source. PMID- 9360113 TI - Intelligent Li ion battery management based on a digital signal processor for a moving actuator total artificial heart. AB - An intelligent Li Ion battery management (ILBM) system was developed based on a digital signal processor (DSP). Instead of using relatively complicated hardware charging control, a DSP algorithm was used, and favorable characteristics in volume, mass, and temperature increase of the implantable battery were achieved. In vitro tests were performed to evaluate the DSP based algorithm for Li Ion charging control (24 V dc motor input power 16 W, 5 L/min, 100 mmHg afterload). In this article, the first improvement was volume reduction using a Li Ion battery (3.6 V/Cell, 900 mA, seven cells: 25.2 V, 22.7 W). Its volume and mass were decreased by 40% and 50% respectively (40*55*75 mm, 189 g), compared to previously reported results, with total energy capacity increased by 110% (more than 60 min vs 25 min run time in the other battery). The second improvement includes the ILBM, which can control the performance detection for each unit cell and has a low temperature rise. The ILBM's unit cell energy detection was important because the low performance of one cell dropped to 50% of the total performance along with a 20% increase in surface temperature. All electronics for a transcutaneous energy transmission (TET), battery, and telemetry were finalized for hybridization and used for total artificial heat (TAH) implantation. PMID- 9360114 TI - In vitro and in vivo heat dissipation of an electrohydraulic totally implantable artificial heart. AB - The authors evaluated the heat transfer characteristics of an electrohydraulic totally implantable artificial heart (EH-TAH) developed at our institute. In three in vitro experiments, the heat dissipation of the EH-TAH was investigated. First, the EH-TAH was connected to a closed mock circuit filled with 1 L of saline, and driven at an input power of 20 W. The estimated heat conducted to the blood was approximately 10.3 W, which was almost half of the input power. Second, we simulated heat transfer with the circulation of a calf by using a heat exchanger. The amount of heat dissipating directly from the EH-TAH surface was calculated to be 10 W. Third, the temperature of the actuator examined with thermography was found to be almost uniform, and no prominent high temperature area was observed. In an in vivo study, the EH-TAH was implanted for 10 days in a calf weighing 62 kg. The input power was 18 +/- 2 W, the temperature of the actuator-tissue contacting surface was 39.4 +/- 0.8 degrees C, and that of the pump blood chamber was 39.8 +/- 0.4 degrees C. This slight temperature elevation was thought to be attributable to heat dissipation to the blood. On histologic study of the chest wall and the lung in contact with the actuator, vascularized connective tissue envelopes were observed, but unfavorable side effects, such as tissue necrosis, were not observed. These results suggest that the thermal effect of this system is acceptable at the input power used. PMID- 9360115 TI - Magnetic suspension controls for a new continuous flow ventricular assist device. AB - A new continuous flow ventricular assist device (CFVAD III) using a full magnetic suspension has been constructed. The magnetic suspension centers the centrifugal impeller within the clearance passages in the pump, thus avoiding any contact. This noncontact operation gives very high expected mechanical reliability, large clearances, low hemolysis, low thrombosis, and relatively small size compared with current pulsatile devices. A unique configuration of a system of magnetic actuators on the inlet side and exit sides of the impeller gives full five axis control and suspension of the impeller. The bearing system is divided into segments that allow for three displacement axes and two angular control axes. For the first suspension tests, a decentralized set of proportional, derivative, and integral (PID) controllers acting along the modal coordinates are used to suspend the impeller. The controller design takes into account the blood forces acting on the magnetically suspended impeller, the unbalance forces on the impeller and gravitational loads during various body motions. In the final design, the bearing control axes will be coupled together through fluidic forces so the electronic feedback controller is a centralized multiple input, multiple output controller. The control system design must be robust against these types of externally imposed loads to keep the impeller centered and avoid blood damage. This article discusses the dynamic model, controller, and controller implementation for the magnetic suspension controller of CFVAD III. PMID- 9360116 TI - Selection and evaluation of blood- and tribologically compatible journal bearing materials. AB - A critical issue in the Cleveland Clinic Foundation (CCF) Innovative Ventricular Assist System (IVAS) blood pump is the selection of materials for the blood lubricated journal bearing. Under normal operating conditions, the journal bearing geometry creates a thick blood film that separates the rotating and stationary surfaces. However, since start-up and certain transients could cause temporary contact, the material pair selected for these surfaces must be both tribologically and blood compatible. Combinations of two biocompatible alloys were tested: a titanium-zirconium-niobium alloy (Ti-13Zr-13Nb) and a zirconium niobium alloy (Zr-2.5Nb). A standard pin-on-disk tester was used, with the contact surfaces lubricated by glycerol/saline mixtures simulating the viscosity range of blood. One test series evaluated start-up conditions; the other modeled a high-speed rub that might occur if the fluid film broke down. Results showed that the preoxidized Zr-2.5Nb pin/Ti-13Zr-13Nb disk combination was superior at all sliding velocities; a self-mated Zr-2.5Nb pair also showed promise. The oxide film on a self-mated Ti-13Zr-13Nb pair, and a Ti-13Zr-13Nb pin and Zr-2.5Nb disk combination did not show adequate wear life. More work remains to explain distinct performance differences of certain combinations, with more data needed on mechanical properties of thin, hard coatings on softer metal substrates. PMID- 9360117 TI - Development of an implantable centrifugal blood pump for circulatory assist. AB - An implantable centrifugal pump (ICP) for prolonged circulatory assist has been developed, at 320 ml and 830 g. A central balancing hole was made in its impeller for better antithrombogenicity. Waterproofing and histocompatibility were supported by a silicone seal and a casing made of titanium and acrylic resin. Overall efficiency was 30% and normalized index of homolysis was 0.003 mg/dl, the same value as the BP-80, at a flow rate of 5 L/min and a head of 100 mmHg. Antithrombogenicity and hemolytic properties of the ICP were investigated in paracorporeal implantation in three goats (61-71 kg). Exothermicity, anatomic fit, and water tightness of the ICP were evaluated in intrathoracic implantation in an adult goat (66 kg). The ICP could run paracorporeally for 50, 200, and 381 days. There was no thrombus in the ICP after 381 days' pumping, and the ICP could run in the chest cavity for 40 days. The temperature of the motor rose 1.8 +/- 0.3 degrees C from that of the pleura. Moisture content of the seal remained normal. The ICP was completely covered with smooth fibrous tissue. Although a small area of atelectasis was found in the lingula, neither lung adhesion nor necrosis of the chest wall was observed. The ICP has satisfactory antithrombogenicity, hemolytic property, water tightness, anatomic fit, and exothermicity for use as an implantable circulatory assist device. PMID- 9360118 TI - Design of a DSP controller for an innovative ventricular assist system. AB - The design and development of the digital signal processor controller for an innovative ventricular assist system is presented. A DSP56005 is used as the central processor, with other peripheral components. System hardware and software were developed through the advanced development system, and stand alone operation of the system was also accomplished. Two different control modes--current control mode and speed control mode--were developed and investigated. Performance of efficiency and dynamic response were examined through experimental testing. PMID- 9360119 TI - In vitro and in vivo evaluation of a left-right balancing capacity of an interatrial shunt in an electrohydraulic total artificial heart system. AB - The authors evaluated the basic performance of an interatrial shunt (IAS) made by punching a hole in the atrial septum, in accommodating the left-right imbalance in our electrohydraulic total artificial heart (EHTAH) system. In an in vitro study conducted in a closed mock circuit connected with the EHTAH, the interatrial pressure gradient changed in compliance with the amount of bronchial flow and the size of the IAS. The IAS of 4.4 mm diameter or larger maintained the interatrial pressure gradient within physiologically permissible limits when the amount of bronchial flow was 5% of cardiac output or less. A left-to-right one way valve made of a piece of pericardium, a possible option in this IAS method, successfully prevented right-to-left reverse shunt flow through the IAS. In a chronic in vivo study using a calf implanted with the EHTAH for 10 days, a 4.5 mm IAS without the one-way valve demonstrated satisfactory dynamic left-right balancing capacity with a stable interatrial pressure gradient of 4 +/- 1 mmHg over a wide range of atrial pressures. No thrombus was found in or around the IAS at autopsy. The authors conclude that the IAS is a simple and promising means of left-right balancing in the EHTAH system. PMID- 9360121 TI - Portable pneumatic biventricular driver for the Thoratec ventricular assist device. AB - As patients with left ventricular (LVAD) and biventricular assist devices are supported for increasingly long durations while awaiting heart transplantation or cardiac recovery, there is a need to facilitate greater patient mobility and ambulation. To meet these needs, the authors have developed the Thoratec TLC-II Portable VAD Driver, which is a small brief-case sized (33 x 34 x 13 cm) pneumatic unit for Thoratec's paracorporeal and implantable VADs. The TLC-II consists of an electric motor driven air compressor for supplying both positive and negative air pressure, solenoid valves for switching between LVAD/RVAD filling and ejection, and microcontroller based electronics and firmware. Four power sources are provided: external power, two rechargeable lithium-ion battery packs, and an emergency battery that drives an independent electronic back-up system. The 8 kg TLC-II can be carried by hand, with a shoulder strap, or pushed on a wheeled mobility cart. Trend information stored in the TLC-II can be accessed by an external system computer with a color touchscreen mounted on a docking station, which also houses the battery charger. Control configurations (univentricular/biventricular operation, beat rates, etc.) are entered on the touchscreen and programmed into the TLC-II. In vitro testing demonstrates the ability to pump VAD outputs up to 7 L/min. By providing improved patient mobility, this small driver will enhance rehabilitation and improve the quality of life of VAD patients. PMID- 9360120 TI - Development of a 6 x 18 inch rheology tunnel for experimental fluid dynamics investigation. AB - The Ohio State University (OSU) and the Cleveland Clinic Foundation (CCF) developed a 6 x 18 inch low velocity Rheologic Research Tunnel to do flow visualization and other experimental fluid studies, particularly on scaled-up models of cardiovascular devices, such as the CCF's Innovative Ventricular Assist System. The large test section (TS) permits detailed data to be obtained that would be inaccessible with a smaller test prototype. A particular feature of the OSU-CCF program is the use of a non-Newtonian blood analog (NNBA), so the effect of the shear-thinning behavior of blood on the local development of separation, stagnation, and flow patterns can be studied. The TS can simulate a pressure driven slit flow of 6 x 18 in., or the external flow around a vane or blade having an aspect ratio of 1. Maximum pressure is 8.5 psig, while the maximum velocity is 21.7 in/sec. The fluid supply tank has a capacity of 500 gal of NNBA and, with its associated filtration and circulation systems, can be adapted to studies of large transparent models better studied outside the TS. Using 2 pumps, flow rates of 98-610 gal/min can be provided. Instrumentation includes thermistors, a 48 port pressure scanner with pressure transducers, a data acquisition system, and a digital video camera. Dye and hydrogen bubble systems have been developed. Development of such a facility presents problems not encountered in more typical water tables or wind tunnels. These include fundamental issues such as providing a uniform flowfield; practical issues with respect to priming, operating, and obtaining data from the system; and safety considerations. For the very large volume of NNBA, a xanthan gum solution is used, whose shear-thinning behavior depends not only on concentration, but also on age and prior shear history. The lessons learned are presented, permitting others to efficiently develop systems suitable to their testing needs. PMID- 9360122 TI - Fluid dynamic characteristics of monopivot magnetic suspension blood pumps. AB - A monopivot magnetic suspension blood pump is a centrifugal pump under development with a magnetic suspension and a ceramic pivot to support the impeller with minimum contact. The pump size has been reduced by implementing a direct impeller drive mechanism in place of a magnetic coupling and motor. Flow visualization studies revealed that high shear, which seems to be closely related to hemolysis, concentrates in boundary layers near the walls. This implies that fluid dynamic shear can be reduced not by widening the gap, but by reducing the impeller velocity. Therefore, compared with the results of the previous semi-open curved vane impeller model, impeller velocity was reduced by 30% with a closed impeller having radial straight vanes, and smaller impeller/housing gaps. The volute shape around the impeller tip was also changed such that the outflow from the impeller enters along the center plane of the volute. To examine the effect of the improvements, hemolysis testing was conducted and found that the newly developed closed impeller model generated a lower level of hemolysis than the previous semi-open impeller model. PMID- 9360123 TI - Condition monitoring of rotary blood pumps. AB - Long-term, trouble-free operation of ventricular assist devices (VADs) is critical to the patient. A catastrophic failure of the VAD could cost the patient's life, thus defeating the purpose of the device. The targeted 90% 5 year reliability also implies that the average device life would exceed the 5 year limit. Time based explantation of the device after the fifth year will replace many devices with significant additional life, subject the patient to unnecessary surgical risk, and increase costs. To preclude the need for time based replacements and prevent catastrophic failures, a condition monitor is proposed in this article for early detection of faults in VADs. To develop this monitor, the effectiveness of various sensing and monitoring methods for determining the VAD condition is investigated. A Hemadyne pump was instrumented with a set of eight sensors, and a series of experiments were performed to record and analyze signals from the normal and abnormal pumps with five different faults. Statistical, spectral, envelope, and ensemble averaging analyses were performed to characterize changes in sensor signals due to faults. Experimental results indicate that statistical and frequency information from the acceleration and dynamic pressure signals can clearly detect and identify various VAD faults. PMID- 9360124 TI - Thin film rechargeable lithium batteries for implantable devices. AB - Thin films of LiCoO2 have been synthesized in which the strongest x-ray reflection is either weak or missing, indicating a high degree of preferred orientation. Thin film solid state batteries with these textured cathode films can deliver practical capacities at high current densities. For example, for one of the cells, 70% of the maximum capacity between 4.2 and 3 V (approximately 0.2 mAh/cm2) was delivered at a current of 2 mA/cm2. When cycled at rates of 0.1 mA/cm2, the capacity loss was < or = 0.001%/cycle. The reliability and performance of Li-LiCoO2 thin film batteries make them attractive for application in implantable devices such as neural stimulators, pacemakers, and defibrillators. PMID- 9360125 TI - Development of a custom designed TAH using rapid prototyping. AB - The failure of the orthotopic implantation of a totally implantable artificial heart (TAH) was due mainly to anatomic mismatches in the conduits of the conventional TAH system. To overcome this anatomic incompatibility, a custom design and fabrication process was designed using the rapid prototyping (RP) technique. After three dimensional reconstruction of magnetic resonance imaging of the thoracic cavity and vascular remnants of the recipient, study of anatomic fit was done using the reconstructed thoracic model and three dimensional computer aided design (CAD) model. The direction of the inflow and outflow conduits of the blood sac was changed with a Unigraphics CAD. The RP model of the designed chamber was fabricated and examined for anatomic compatibility. Through this approach, the minute directional mismatch of the inflow and outflow conduits was improved. Thus, a new custom designed moving actuator Korean TAH with CAD and RP techniques was developed. PMID- 9360126 TI - Power generation from four skeletal muscle configurations. Design implications for a muscle powered cardiac assist device. AB - The development of long term cardiac assist devices is currently limited by the lack of an appropriate totally implantable power source. Transformed fatigue resistant skeletal muscle has been proposed as such a power source. The goal of this study was to determine the optimal latissimus dorsi muscle (LDM) configuration capable of obtaining maximum power output. Four separate in situ configurations were prepared: a latex compliance chamber placed between the LDM and chest wall (Sub-Dorsi), a chamber wrapped in a skeletal muscle ventricle (Circular), linear measurements from the thoracolumbar origin (Linear Origin), and linear measurements from the humeral insertion (Linear Insertion). A device was designed to measure the power output from each configuration in watts per kilogram of muscle. Eight LDMs were acutely studied at varying levels of pre load. Performance characteristics were measured in each configuration. Peak power outputs were as follows: Sub-Dorsi: 8.3 +/- 1.6 W/kg at 50 cc or 11.6 N pre-load; Circular: 16.4 +/- 6.2 W/kg at 50 cc or 16.9 N; Linear Origin: 47.1 +/- 4.4 W/kg at 23.4 N; and Linear Insertion generated 59.9 +/- 12.1 W/kg at 26 N. Analysis of variance comparison revealed a significance of p < 0.0001. A linear oriented LDM is capable of generating maximal power output. Confirmation of these findings in transformed, conformed, fatigue resistant muscle will provide important performance information essential for the optimal design of implantable muscle powered ventricular assist systems. PMID- 9360127 TI - Pulmonary microcirculation during pulsatile and non pulsatile perfusion. AB - During development of a rotary blood pump as an assist device, the efficacy of non pulsatile perfusion to the end organ has to be verified. However, there are few evaluations of two different perfusion mechanisms through the tissue microcirculation. In this study, the pulmonary microcirculation was analyzed by vital microscopic observation. Wistar rats weighing 400-500 g were anesthetized and ventilated by a respirator. After establishing right heart bypass from the right atrium to the pulmonary artery using a roller pump, the pulmonary microcirculation was observed during intravenous infusion of bovine albumin tagged with fluorescein isothiocyanate. The images were recorded on a videotape through an ultra-sensitive SIT TV camera. Initially, the pulmonary circulation was pulsatile, produced by the native heart, and the pulmonary capillary network was evenly perfused by the blood. After starting the pump, the flow became non pulsatile and the distribution of capillary perfusion was displaced to the short circuit connecting the pulmonary arterioles and venules. Flow distribution during non pulsatile perfusion was heterogeneous compared with pulsatile perfusion. This result suggests that non pulsatile flow may lead to the deterioration of function. Further investigation is necessary to evaluate the relationship between the microcirculation and organ function. PMID- 9360128 TI - Establishment of flow estimation for an implantable centrifugal blood pump. AB - A less invasive and non thrombogenic flow estimation of an implantable centrifugal blood pump (ICBP) has been developed, which was derived from electric power consumption, the rotating speed of a motor, and blood viscosity presumed by hematocrit and body temperature. The power consumption and the rotating speed of the motor were measured by a wattmeter every 0.2 sec. Accuracy and stability of the estimated flow (EF) were investigated during in vitro and in vivo experiments. The EF was compared with a measured flow rate (MF) monitored by an electromagnetic flowmeter. During in vitro experiments, the EF and MF were measured at 79 operating points. The ICBP was driven in a closed mock loop filled with goat blood with hematocrit values of 21.5, 28, 34, and 42%. During in vivo experiments, the ICBP was implanted in the chest cavity of a goat and driven for 40 days with continuous estimation of the bypass flow rate. Blood was taken to determine hematocrit value several times a week. The temperature of the pleura away from the ICBP was measured every 15 min. A linear correlation between the EF and MF was observed, and the correlation coefficient between the EF and MF was 0.99 during in vitro examinations. An averaged error of the EF was 0.5 L/min, with the MF ranging from 2.3 to 8.1 L/min during in vivo experiments. In conclusion, flow estimation was established with good stability and accuracy in both in vitro and in vivo experiments. PMID- 9360130 TI - In vivo studies of an implantable energy convertor for skeletal muscle powered cardiac assist. AB - A device that harnesses the mechanical energy of skeletal muscle contracting in a linear configuration has been implanted in goats. This energy convertor transforms muscle work to hydraulic energy that could drive a variety of cardiac assist devices. The device is mounted with a rib clamp and plate affixed to the sternum by cortical bone screws. A transcutaneous hydraulic line carries a silicon based working fluid to an external system that controls the muscle load. In 60 to 70 kg goats, the latissimus dorsi insertion was reattached to the energy convertor. A Telectronics myostimulator with intramuscular electrodes stimulated the latissimus dorsi. In acute implants, hydraulic pressures in excess of 150 psi were obtained. Chronic implantation of the device allowed system evaluation in the conscious unanesthetized animal. Two weeks after implant, hydraulic pressures in excess of 200 psi were obtained and energy transferred to the external loading system exceeded 1 J per contraction. Six weeks after implant, the device continued to cycle freely. These initial results are very promising and suggest an implantable energy convertor is feasible. Development of an energy convertor is an important step toward tether-free skeletal muscle powered cardiac assist devices. PMID- 9360129 TI - Early changes in circulating blood volume and volume regulating humoral factors after implantation of an electrohydraulic total artificial heart. AB - The early changes in circulating blood volume (CBV) and volume regulating humoral factors after implantation of an electrohydraulic total artificial heart (EH-TAH) were investigated in a calf and compared with results in a sham operated control calf. CBV was measured by the dye dilution method using indocyanine green. CBV and humoral factors were periodically investigated. In the EH-TAH implanted calf, the cardiac output was estimated at 6-7 L/ min (94-109 ml/kg/min), and the aortic pressure and aerobic metabolic condition were favorable. Nevertheless, the CBV was increased to 132 and 168% of the pre-operative value (range in the control calf, 83-103%) on post operative days 4 and 8, respectively. The atrial natriuretic peptide level on days 2, 5, and 7 was 23, 170, and 240 (in the control calf, 19-61) pg/ml, respectively, and the antidiuretic hormone level was 7.3, 2.0, and 1.3 (0.5-1.3) pg/ ml, respectively. The plasma renin activity was 3.2, 3.7, and 3.1 (0.5-0.3) ng/ml/hr, respectively. The angiotensin-I and angiotensin-II levels were also increased in the EH-TAH implanted calf. It is concluded that significant water retention occurs even at sufficient cardiac output early after EH-TAH implantation. The changes in humoral factors are suggested to arise secondary to the increased CBV or other unknown factors. PMID- 9360131 TI - A solar cell system for extension of battery run time in a moving actuator total artificial heart. AB - An implantable total artificial heart (TAH) system has strong dependence upon the external battery performance for operation. Even under sophisticated battery management control, the usable external battery performance continues to decrease, which limits TAH performance. One of the ways to overcome this energy problem is to use a solar system (SS). An SS can provide electrical power for the partial TAH drive or battery recharge. This article presents a new concept for use of the solar cell for obtaining double external battery performance. To achieve it, numeric simulations were carried out to obtain the proper magnitude of solar parameters. In the TAH used, the battery power for a cardiac output of 4 6 L/min is approximately 17 W/20 min. From simulated results, the optimal power and voltage of the SS were found to be 7 W, Voc = 27 V in the case of the 24 V motor. Each solar cell includes Voc = 0.5 V, Isc = 37 mA/cm2, FF (fill factor) = 0.77, and efficiency = 10%. Based on the simulation, the effect of solar power capacity on battery run time was studied. With use of 6.5 W SS (W 304 x H 245 x D 16 mm, 1.1 kg), battery performance decreased in vitro from 100% (fully charged) to > 55% vs 0% in the conventional battery system after 20 min operation. However, it dropped to below 20% when using W SS (W 192 x H 192 x D 16 cm, 0.6 kg). The results showed doubled battery run time could be obtained compared with a system without the SS. It was concluded that the proposed SS can be put to practical use as a future energy source for a TAH. PMID- 9360132 TI - Characteristics of mixed venous oxygen saturation and physical activity as parameters for artificial heart control. AB - Mixed venous oxygen saturation (SvO2) and physical activity (PhyAc) are practical candidates as parameters of total artificial heart (TAH) control because SvO2 can be measured through a transparent blood pump housing with infrared rays and PhyAc can be calculated from signals of an accelerometer used for rate response pacemakers. Although the methods for measurement of the parameters have already been developed, characteristics of these parameters for TAH control, such as during exercise, are still unclear and were examined in this study. SvO2, cardiac output (CO), and PhyAc were measured as parameters. Multi-stage treadmill exercise tests were performed. Difference values (DVs) from the value at the start of exercise showed better correlation than did absolute values. Correlation coefficients between DV in CO and DV in SvO2 and between DV in CO and PhyAc were high at -0.82 and 0.72, while the time constants for the change of SvO2 and CO to the PhyAc change were 26 and 32 sec. Although the correlation coefficient between the CO and SvO2 was higher than that between CO and PhyAc, PhyAc responded more quickly to the speed change compared with the response of SvO2 and CO. It was concluded that SvO2 and PhyAc were useful parameters with different characteristics for TAH control during exercise. PMID- 9360133 TI - Method of noninvasive and continuous hemolysis/thrombogenesis measurement by laser photometry during artificial heart development. AB - The purpose of this research is to propose and develop a method to measure hemolysis and thrombogenesis non invasively and continuously to aid in development of an artificial heart. Generally, the optical absorption rate of hemoglobin is influenced by oxygen saturation except at the isosbestic point, which is not influenced by oxygen saturation. The authors, therefore, used an 805 nm laser diode, an optical spectrum analyzer to obtain greater accuracy. An experimental blood circuit system was constructed using a Bio-Pump, Tygon tubing, a soft shell reservoir, and an optical measurement system. Experimental settings for monitoring hemolysis were as follows; blood volume 200 ml, blood flow 6 L/min, and afterload 200 mmHg. Blood was sampled six times (0, 30, 60, 120, 180, and 240 min), and hemolysis in each sampled was measured using a colorimetric method. Comparing continuous laser measurement data with the sample data, an adequate correlation is obtained, proving that the dynamic trend of hemolysis could be continuously measured. Furthermore, to analyze the process of thrombogenesis, simple experiments were performed using blood neutralized by protamine. As a result, the authors could see the process of thrombogenesis as it occurred and could confirm that this method is able to dynamically detect hemolysis and thrombogenesis. PMID- 9360134 TI - An implantable centrifugal blood pump for long term circulatory support. AB - A compact centrifugal blood pump was developed as an implantable left ventricular assist system. The impeller diameter is 40 mm and the pump dimensions are 55 x 64 mm. This first prototype was fabricated from titanium alloy, resulting in a pump weight of 400 g including a brushless DC motor. Weight of the second prototype pump was reduced to 280 g. The entire blood contacting surface is coated with diamond like carbon to improve blood compatibility. Flow rates of over 7 L/min against 100 mmHg pressure at 2,500 rpm with 9 W total power consumption have been measured. A newly designed mechanical seal with a recirculating purge system ("Cool-Seal") is used as a shaft seal. In this seal system, seal temperature is kept under 40 degrees C to prevent heat denaturation of blood proteins. Purge fluid also cools the pump motor coil and journal bearing. The purge fluid is continuously purified and sterilized by an ultrafiltration filter incorporated into the paracorporeal drive console. In vitro experiments with bovine blood demonstrated an acceptably low hemolysis rate (normalized index of hemolysis = 0.005 +/- 0.002 g/100 L). In vivo experiments are currently ongoing using calves. Via left thoracotomy, left ventricular apex-descending aorta bypass was performed utilizing a PTFE (Polytetrafluoroethylene) vascular graft, with the pump placed in the left thoracic cavity. In two in vivo experiments, pump flow rate was maintained at 5-8 L/min, and pump power consumption remained stable at 9-10 W. All plasma free hemoglobin levels were measured at < 15 mg/dl. The seal system has demonstrated good seal capability with negligible purge fluid consumption (< 0.5 ml/ day). Both animals remain under observation after 162 and 91 days of continuous pump function. PMID- 9360135 TI - Morphologic changes of the aortic wall due to reduced systemic pulse pressure in prolonged non pulsatile left heart bypass. AB - The morphologic changes of the aortic wall due to reduced systemic pulse pressure in prolonged non pulsatile left heart bypass (LHB) were investigated. Sixteen adult goats were divided into three groups: the non pulsatile group in which non pulsatile LHB was conducted for 137 days on average, the pulsatile group in which pulsatile LHB was conducted for 79 days on average, and the control group used as the normal control. The average aortic pulse pressures were 12, 48, and 37 mmHg, respectively. At the end of the experiments, the descending aorta was excised and subjected to morphologic examination. The wall thickness of the aorta in the non pulsatile group (1.4 mm) was significantly thinner than that in the pulsatile group (2.2 mm) and the control group (2.0 mm), and the volume ratio of smooth muscle cells (SMC) in the non pulsatile group (37%) was lower than that in the pulsatile group (48%) and the control group (49%). In SMC classification, the proportion of SMC with low activity and low contractility in the non pulsatile group (57%) was high as compared with that in the pulsatile (2%) and control (5%) groups. These results strongly indicate that prolonged non pulsatile LHB causes substantial morphologic changes in the aorta. PMID- 9360136 TI - Long-term animal experiments with an intraventricular axial flow blood pump. AB - A miniature intraventricular axial flow blood pump (IVAP) is undergoing in vivo evaluation in calves. The IVAP system consists of a miniature (phi 13.9 mm) axial flow pump that resides within the left ventricular (LV) chamber and a brushless DC motor. The pump is fabricated from titanium alloy, and the pump weight is 170 g. It produces a flow rate of over 5 L/min against 100 mmHg pressure at 9,000 rpm with an 8 W total power consumption. The maximum total efficiency exceeds 17%. A purged lip seal system is used in prototype no. 8, and a newly developed "Cool Seal" (a low temperature mechanical seal) is used in prototype no. 9. In the Cool Seal system, a large amount of purge flow is introduced behind the seal faces to augment convective heat transfer, keeping the seal face temperature at a low level for prevention of heat denaturation of blood proteins. The Cool-Seal system consumes < 10 cc purge fluid per day and has greatly extended seal life. The pumps were implanted in three calves (26, 30, and 168 days of support). The pump was inserted through a left thoracotomy at the fifth intercostal space. Two pursestring sutures were placed on the LV apex, and the apex was cored with a myocardial punch. The pump was inserted into the LV with the outlet cannula smoothly passing through the aortic valve without any difficulty. Only 5 min elapsed between the time of chest opening and initiation of pumping. Pump function remained stable throughout in all experiments. No cardiac arrhythmias were detected, even at treadmill exercise tests. The plasma free hemoglobin level remained in the acceptable range. Post mortem examination did not reveal any interference between the pump and the mitral apparatus. No major thromboembolism was detected in the vital organs in Cases 1 or 2, but a few small renal infarcts were detected in Case 3. PMID- 9360137 TI - A new method for quantitation of platelet microthrombi and microemboli from cardiopulmonary bypass in organs using 111In labeled platelets. AB - During cardiopulmonary bypass (CPB), showers of microemboli (ME) distribute among the organs and connective tissues according to regional blood flow. Post CPB, ME were quantified by subtracting residual platelets (RP) in the organs of a group of unoperated control Yorkshire pigs (n = 6) from those of operated pigs. The RP level was minimized by heparinization (300 IU/kg) before death and exsanguination. The number of adherent microthrombi (MT) and ME from the oxygenator (OX), arterial filter (AF), and thoracotomy site were determined using 111In labeled autologous platelets (INPLT) (525-585 microCi administered 24 hr before CPB) in two CPB groups (ACT > 400 sec) of 12 pigs (30-35 kg). CPB was carried out at a flow of 2.5-3.5 L/min at 28 degrees C with a roller or a centrifugal pump, OX (Bentley Univox 1.8 m2), AF (0.25 m2), and cardiotomy reservoir (CR) (Bentley BR: 3,500), for 90 (n = 6) and 180 (CPB 180, n = 6) min. Six pigs underwent thoracotomy without CPB. L-Arginine was infused at a dose of 2 mg/ kg/min during CPB (n = 6). Flow cytometry was used to estimate the circulating ME in blood. MT and organ trapped ME were imaged with a gamma camera and measured with an ion chamber and a gamma counter. ME values (percent of injected INPLT dose) in six organs and four connective tissues were calculated for all five groups. INPLT distribution indicated a uniform distribution of low level platelet MT in the CR and AF. Circulating ME amounted to 2.5% of total platelets. In the CPB circuit, ME generation in AF was the rate-limiting step (n = 4 x 10(5)). Similar studies in organs and tissues suggested the presence of a uniform distribution of the total events of ME (n = 500 x 10(6)). ME increase in brain, lung, liver, and skeletal muscle following thoracotomy and CPB was significant. The low level of ME in ischemia sensitive organs also indicated the presence of a thrombolytic threshold for cumulative ME. ME disaggregation was activated at an early stage to prevent ischemic damage, specifically in the brain. Measurement of trapped ME provided a novel, reliable, and one step method of evaluation of thrombogenicity of a CPB device and drugs. PMID- 9360138 TI - Protein adsorption and platelet adhesion on the surface of an oxygenator membrane. AB - Platelet adhesion on an oxygenator membrane is associated with thrombocytopenia or thrombus formation during extracorporeal circulation. The authors evaluated protein adsorption and platelet adhesion on three oxygenator hollow fiber membranes fabricated with polypropylene, silicone, and double layer polyolefin. Adsorbed proteins were analyzed by bicinchoninic acid protein assay, sodium dodecyl sulfate polyacrylamide gel electrophoresis, and Western blot. Platelet adhesion was assessed with enzyme immunoassays using monoclonal antibodies directed against CD42b and CD61. After 3 hr of incubation at 37 degrees C in whole blood, the amount of adsorbed protein was the least on silicone and increased from silicone < double polyolefin < polypropylene. The adsorbed protein pattern was similar; however, silicone showed less adsorption for all protein bands, and the gamma chain of fibrinogen was not detected. In contrast, double polyolefin showed the highest fibrinogen adsorption. The optical density at a wavelength of 450 nm for CD42b was 1.47 +/- 0.35 in polypropylene, 1.16 +/- 0.38 in silicone, and 1.85 +/- 0.19 in double polyolefin (p < 0.01 vs silicone) and for CD61 0.98 +/- 0.39 in polypropylene, 0.91 +/- 0.22 in silicone, and 1.69 +/- 0.25 in double polyolefin (p < 0.01 vs silicone and polypropylene). These data suggest that silicone is advantageous for long term extracorporeal respiratory support in terms of less platelet adhesion and no plasma leakage through the pores. PMID- 9360139 TI - Design of an oxygenator with enhanced gas transfer efficiency. AB - Membrane oxygenator designs were examined with particular attention to the influence of radial and axial flow around windings of microporous polypropylene hollow fibers. Oxygen transfer performance was calculated, employing the Mockros Leonard modified heat transfer analysis and Curtis-Eberhart normalization methods. Flow through an Avecor Affinity oxygenator was imaged by gamma scintigraphy using a bolus injection of 99mTc-DTPA. Experimental mass transfer correlations were developed for this oxygenator using saline. The oxygen exchange of the Avecor Affinity was slightly less than that for the Medtronic Maxima or COBE Optima models, which are based on similar designs. PMID- 9360140 TI - An improved blood substitute. In vivo evaluation of its renal effects. AB - Nephrotoxicity of free hemoglobin (Hb) based blood substitutes still awaits full elucidation. Previous reports attributed Hb passage through the renal glomeruli to a tendency of the Hb tetramer to dissociate into dimers. Now it has become more evident that the Hb tetramer is able to extravasate. It appears that the electrical charge of proteins plays an important role, with electronegativity and a low isoelectric point favoring intravascular persistence. This effect was utilized in the development of an improved blood substitute, comprising Hb reacted with o-ATP and o-adenosine, to form an intra- and intermolecularly cross linked product, which is reduced with glutathione. The modification reagents possess the desired pharmacologic activities and produce an increase in the electronegative charges on the Hb surface. All Hb polymers and chemically modified tetramers present in this solution have a uniform electronegative charge, with a pl of 6.1-6.2. In this present study, unmodified bovine Hb and an improved blood substitute were used for the replacement of 40% of the total blood volume in rats. The nephrotoxic effect was investigated by the determination of urinary output, glomerular filtration rate (GFR), fractional excretion of sodium (FENa), potassium (FEK), and chloride (FECl), urine/plasma osmolality ratio, and urine N-acetyl-beta-D-glucosaminidase (NAG) level. The free Hb and non heme protein contents in the urine were analyzed by using isoelectric focusing and size exclusion liquid chromatography methods. The results indicate that unmodified Hb is nephrotoxic. An initially elevated urinary output was followed by a significant oliguria associated with decreased GFR, FEK, and FECl and elevated FENa and NAG. Severe hemoglobinuria was associated with proteinuria. Analysis of urine from unmodified Hb treated rats revealed the presence of Hb tetramers. Histopathological examination of the kidneys showed cytoplasmic vacuolization of proximal tubular epithelium. On the contrary, an improved blood substitute did not produce any nephrotoxic reactions. It was found that this Hb solution did not pass through the renal glomerular barrier and was not present in urine samples. In conclusion, such a chemical and pharmacological alteration of Hb molecules reduced their interaction with renal glomeruli and suspended nephrotoxicity. PMID- 9360141 TI - Development of a low flow resistance intravenous oxygenator. AB - A potentially attractive support device for patients with acute respiratory failure is an intravenous membrane oxygenator. One problem, however, is that the membrane surface area required for sufficient gas exchange can unduly increase vena caval pressure drop and impede venous return. The purpose of this study was to design and develop an intravenous oxygenator that would offer minimal venous flow resistance in situ. The device uses a constrained fiber bundle of smaller cross sectional size than the vena cava so as to effect an intentional shunt flow of venous blood around the fiber bundle and reduce the venous pressure drop caused by the device. A pulsating balloon within the fiber bundle redirects part of this shunt flow into reciprocating flow in and out of the fiber bundle. This offers dual advantages: 1) Blood flow through the fiber bundle is mainly perpendicular to the fibers; and 2) the requisite energy for driving flow comes largely from the pneumatic system pulsating the balloon, not from a venous pressure drop. In this mode a full length device with a 2 cm fiber bundle in a 2.5 cm blood vessel would offer a pressure drop of only a few millimeters of mercury. The use of constrained fiber bundles requires good uniformity of fiber spacing for effective gas exchange. Several prototypes have been fabricated, and CO2 and O2 exchange rates of up to 402 and 347 ml/min/m2 have been achieved during acute animal implantation. PMID- 9360142 TI - A new double lumen balloon catheter for retrograde cerebral perfusion via jugular vein cannulation. AB - A new catheter for retrograde cerebral perfusion (RCP) was developed that can be used to deliver blood directly into the internal jugular vein (IJV) beyond the venous valves at the jugular-subclavian junction and prevent blood from draining into the lower half of the body. This catheter can be inserted into the IJV via a standard puncture technique by use of a 14 Fr sheath. The catheter shaft has two channels for balloon inflation and blood perfusion, respectively. A balloon for occlusion of drainage veins (superior vena cava and azygos vein) is installed at the catheter tip. Side holes, through which oxygenated cold blood is delivered into the IJV, are located 95 mm from the catheter tip. In a mock circulatory study, the pressure at the perfusion line (16-118 mmHg) increased with the increasing flow rate (0-400 ml/min). In clinical application, under circulatory arrest with profound hypothermia, inflation of the balloon effectively reduced blood drainage into the lower half of the body and, consequently, RCP was successfully performed (flow rate, 300-350 ml/min; pressure at the IJV, 15 mmHg). Because all of these procedures were controlled from outside the operative field, RCP by use of this catheter could be useful in distal arch replacement via left lateral thoracotomy. PMID- 9360143 TI - Clinical evaluation of a silicone coated hollow fiber oxygenator. AB - In this article, the clinical experience with a cardiopulmonary bypass (CPB) using a newly developed hollow fiber oxygenator with an ultra-thin layer of silicone is reported. A comparative study of biocompatibility between the new oxygenator and a heparin coated oxygenator is also described. The CPB was performed with a silicone coated oxygenator, Mera Excelung Binding Prim HPO 15 H C (Group I, n = 6) or Binding Prim HPO 25 H-C (Group II, n = 10) (Senko Medical Instrument Mfg., Tokyo, Japan). Air could be vented through the silicone coated hollow fibers, and it was easy to prime the circuits. The CPB duration was 101 +/ 37 min and 170 +/- 64 min for Groups I and II, respectively. There were no deaths and no complications from CPB. Partial arterial pressure of O2 levels 60 minutes after the start of CPB were 529 +/- 28 mm Hg and 529 +/- 28 mmHg for Group I and II, respectively. Partial arterial pressure of CO2 levels 60 min after the start of CPB were 36.4 +/- 4.6 mmHg and 39.4 +/- 4.4 mmHg, respectively. Plasma free hemoglobin at 60 min was 33.5 +/- 17.2 mg/ dL and 46.7 +/- 26.1 mg/dL for Groups I and II, respectively. As an evaluation of biocompatibility, the effects of the new oxygenator on platelet activation (GP Ib, IIb/IIIa), coagulation (TAT), fibrinolysis (PIC), and inflammatory response (C3a, granulocyte elastase) were investigated during CPB and comparing to those of the heparin coated oxygenator. There were no significant differences in GP Ib, GP IIb/IIa, TAT, PIC, and granulocyte elastase between the two oxygenators. However, 60 min after the start of CPB, the C3a was significantly lower for the new oxygenator group than for the heparin coated oxygenator group (p < 0.03). The new oxygenator showed good gas transfer, low hemolysis, and good biocompatibility. Because of its durability and good biocompatibility, the new oxygenator was determined to be suitable for prolonged extra corporeal circulation. PMID- 9360145 TI - Characteristics of an albumin dialysate hemodiafiltration system for the clearance of unconjugated bilirubin. AB - Extraction of protein bound liver failure toxins, such as unconjugated bilirubin, short chain fatty acids, and aromatic amino acids has been reported using hemodiafiltration with albumin in the dialysate, but the characteristics of such a system have not been described. Therefore, bilirubin clearance using albumin dialysate hemodiafiltration was evaluated in the setting of different dialysate albumin concentrations, varying temperature and pH. An in vitro continuous hemodiafiltration circuit was used with single pass countercurrent dialysis. Unconjugated bilirubin was added to bovine blood and filtered across a polyalkyl sulfone (PAS) hemofilter using matched filtration and dialysate flow rates. The serial bilirubin content was measured and first order clearance kinetics verified. The clearance rate constants were calculated for three dialysate groups of different albumin concentration at constant temperature and pH (group 1: 10 g/dl albumin, n = 5; 2 g/dl albumin, n = 5; normal saline, n = 5), and three groups of different temperature and pH at constant albumin dialysate concentration (group 2: pH = 7.0, temperature = 20 degrees C, n = 5; pH = 7.5, temperature = 20 degrees C, n = 5; pH = 7.0, temperature = 40 degrees C, n = 5). Comparisons were made with ANOVA and Tukey post hoc analysis. When albumin was used in the dialysate, the 2 g/dl group cleared bilirubin 3.1 times faster than saline alone (p = 0.001), and the 10 g/dl group was superior to both (p = 0.001). There were no measurable differences between the 2 g/dl groups at the various temperatures tested (p = 0.08), but the clearance was less at a pH of 7.5 (p = 0.015). The clearance of unconjugated bilirubin is greatly enhanced with the use of albumin containing dialysates when compared to traditional crystalloid hemodiafiltration, is greater at lower pH, and seems to be unaffected by temperature. PMID- 9360146 TI - Tissue engineering of skeletal muscle. Highly dense, highly oriented hybrid muscular tissues biomimicking native tissues. AB - A highly dense, highly oriented hybrid muscular tissue was devised using C2C12 cells (skeletal muscle myoblast cell line) and Type I collagen. A cold mixture of C2C12 cells suspended in DMEM (Dulbecco's modified Eagle's medium; Gibco Lab Inc., Grand Island, NY) and Type I collagen solution was poured into capillary tube molds of two different sizes (inner diameters: 0.90 mm and 0.53 mm, respectively) sealed at each end. After centrifugation (1000 RPM, 5 min) and subsequent thermal gelation, a rod shaped gel was formed. The resultant gel shrank to become a highly dense tissue after incubation on an agarose gel coated dish. Small diameter rod shaped tissues were composed of numerous multi-nucleated myotubes and a few necrotic cells. On the other hand, a ring shaped tissue fabricated by centrifugation with a specially devised agarose gel mold was subjected to cyclic stretching at 60 RPM. The resultant highly dense, highly oriented hybrid muscular tissue involved both densely accumulated cells and collagen fiber bundles, which tended to be aligned in the direction of stretching. Sequential procedures of a centrifugal cell packing method and a mechanical stress loading method facilitated fabrication of hybrid muscular tissues similar to native muscular tissues in terms of cell density and orientation. PMID- 9360144 TI - Influence of cardiopulmonary bypass on platelet and neutrophil accumulations in internal organs. AB - The authors employed gamma scintigraphy to quantify the post bypass accumulations of platelets and neutrophils in the lung, liver, and heart of adult pigs subjected to a standard 90 min regimen of normothermic cardiopulmonary bypass (CPB). Coated and uncoated microporous polypropylene oxygenator circuits were studied for Cobe Duo (Arvada, CO) oxygenators (amphophilic silicone-caprolactone oligomer [SMA] coating, n = 8 each) and Medtronic Maxima (Irvine, CA) oxygenators (Carmeda heparin coating, n = 5 each). Images of cells in the organs (deposited + blood pool) were corrected for tissue absorption and other factors and compared for a 2 hr period post CPB, using repeat measures ANOVA and rank tests. Platelet accumulations in internal organs correlated positively with whole blood platelet counts and negatively with platelet deposits in oxygenators during CPB. In general, uncoated CPB circuits significantly reduced platelet and neutrophil accumulations in lung, liver, and heart versus preCPB controls for the post CPB interval, for both systems. The SMA treatment significantly increased platelet accumulations versus uncoated controls in lung, liver, and heart for the 2 hr period, including the majority of the post CPB sampling intervals; platelet densities did not reach preCPB levels. Neutrophil accumulations were unaffected by the SMA coating. Carmeda heparin treatment significantly increased platelet accumulations in the liver, but not lung or heart. Despite preservation of circulating neutrophils observed with the Carmeda heparin treatment, neutrophil accumulations in internal organs were not elevated post CPB. PMID- 9360148 TI - Blood urea levels 30 minutes before the end of dialysis are equivalent to equilibrated blood urea. AB - The steady decline in blood urea during high efficiency hemodialysis is followed by a rebound phase after dialysis in which the level of urea rises to an equilibrium value (Ct + 30) that may be up to 20% higher than the immediate post dialysis (Ct) concentration. The artificially low urea concentration immediately after dialysis leads to an overestimate of the efficiency of the dialysis calculated by Kt/V if the true equilibrium blood concentration of urea is not used in the calculation by the single-pool urea kinetic model. The measurement of equilibrium urea concentration requires a blood sample approximately 30 min after hemodialysis, which is an encumbrance on dialysis patients. This study was undertaken to determine whether an intradialytic sample taken 30 min before the end of dialysis (Ct - 30) may be representative of the equilibrium sample, and to compare the Kt/V using the Ct - 30 and Ct + 30 samples. Thirty-six patients were studied and blood urea concentrations were measured half an hour before the end of dialysis (Ct - 30), at the end of dialysis (Ct), and half an hour after the end of dialysis (Ct + 30). Kt/V (Daugirdas method) was calculated using urea concentration 30 min before the end of dialysis (Kt/Vt - 30) and was compared with Kt/V calculated using equilibrium urea concentration (Kt/Vt + 30). There were no significant differences between the Kt/Vt - 30 and the KtVt + 30 (1.25 versus 1.22, p = 0.65). The correlation between Kt/Vt - 30 and Kt/Vt + 30 was excellent with r2 = 0.93, regression y = 1.05 x -0.033. Kt/Vt - 30 also compared favorably with the Kt/V double pool method (Kt/Vdp) described by Daugirdas (1.25 versus 1.19, p = 0.23). Using the Ct - 30 to calculate Kt/V by the percent urea reduction methods of jindal (Kt/Vpru) decreases the Kt/V value by 0.14 on average, but it remains significantly higher than the Daugirdas method. The authors conclude that calculations using urea concentration 30 min before the end of dialysis improves the accuracy of dose estimation in high efficiency dialysis, without inconveniencing the patient. PMID- 9360147 TI - Stimulation of growth and migration of vascular endothelial cells by vascular endothelial growth factor transduced smooth muscle cells in co-culture. AB - Vascular endothelial growth factor (VEGF) is a secreted mitogen with high specificity toward endothelial cells. Expression of VEGF by smooth muscle cells in vivo may be an important stimulus for the regrowth of the endothelium after damage caused by interventions such as angioplasty. The levels of VEGF secreted by cultured smooth muscle cells minimally stimulated growth of endothelial cells in co-culture. Full length cDNA for the 165 amino acid residue, bovine VEGF (VEGF165), was isolated from calf liver total RNA by reverse transcriptase polymerase chain reaction (RT-PCR) techniques, and used to generate plasmid constructs for transfection. Bovine aortic smooth muscle cells (BSMC), stably transfected with VEGF165 plasmid DNA, secreted mitogen into conditioned culture medium at levels that are physiologically relevant (2-4 ng/ml). Transformed BSMC stimulated growth of bovine aortic endothelial cells (BAEC) in co-culture, to a significantly greater extent than mock transfected BSMC. Migration of BAEC was also enhanced by the presence of VEGF transduced BSMC. These data suggest that smooth muscle cells, genetically engineered to produce VEGF, may provide biologic linings in cardiovascular prostheses that could promote the growth of endogenous endothelial cells. PMID- 9360149 TI - Hemodialysis patient management by telemedicine: design and implementation. AB - The authors describe the design and implementation of a personal computer based telemedicine system for managing patients by telemedicine. With three identical systems connected by high speed T1 lines, the physician (or allied healthcare giver) can interact, by videoconferencing, and by using multimedia files, with patients at two remote hemodialysis sites. The physician is able to visualize specifically the patient's fistula/graft, and auscultate fistula, heart and lung sounds, and incorporate still pictures or audio sounds in the patient's multimedia database folder, which also contains an electronic and paperless medical record. In addition there is the capability of downloading into this database all the machine parameters during dialysis. PMID- 9360150 TI - Free radicals and oxidative stress challenge dialysis patients: effects of two different membranes. AB - Patients with end-stage renal disease (ESRD) who undergo hemodialysis manifest pronounced oxidative stress (OS), for the antioxidant system is inadequate to correct the imbalance between generation and scavenging of reactive oxygen species (ROS). To clarify the role of two different membranes on the OS, we measured plasma lipid peroxidation (LPO) and erythrocyte concentration of several antioxidant enzymes on 20 controls and 6 patients on bicarbonate dialysis (BHD). At 7 days intervals, 2 BHD sessions were done on the same 6 hemodialysis patients: the two BHD sessions were similar, except for the membrane used (cuprophan, first study; regenerated cellulose = Bioflux, second study, 7 days later). Before, during, and after each session (0', 30', 60', 120', end, 30' after BHD end), several blood samples were drawn. Lipid peroxidation and erythrocyte glutathione (GSH), superoxide dismutase (SOD), and catalase were spectrophotometrically determined (Bioxytech, France), but for erythrocyte glutathione peroxidase (Gpx) and G-6-PD, Gunzler's and Beutler's methods were used, respectively. Both membranes induce a significant decrease in LPO (p < 0.01) and an increase in erythrocyte SOD (p < 0.05). Bioflux shows some peculiar effects: a significant increase in erythrocyte GSH (p < 0.05) and erythrocyte catalase (p < 0.01) with a gradual increase of erythrocyte SOD and catalase/SOD ratio. Cuprophan, on the contrary, causes a sudden increase in erythrocyte SOD, while erythrocyte catalase decreases. These data support the view that Bioflux induces an OS lower than cuprophan because with the former, increased H2O2 production leads (thanks to catalase and GPx action) to water generation. With cuprophan, instead the reduced SOD/catalase ratio causes a greater H2O2 generation and a lower conversion to water. PMID- 9360151 TI - Blood flow analysis for the secondary impeller of an IVAS heart pump. AB - The rotodynamic heart pump (IVAS), designed by the Cleveland Clinic Foundation, includes a secondary flow path along the journal bearing, through a secondary impeller, and over the rotor outer surface. The flow behaviors of the blood through the journal bearing and the secondary impeller are investigated by a computational fluid dynamics method that solves the 3-dimensional Navier-Stokes equations using a new solution algorithm. Results of the analyses include: 1) the blood flow patterns within the journal bearing, 2) the effect of the non-uniform bearing clearance on the flow patterns of the impeller cavity, 3) the flow patterns around a secondary impeller blade that include effects of tip clearance and the gap between the blade and the inner or outer side wall, 4) effects of the blade angles on the secondary impeller performance, and 5) the shear stress distribution. PMID- 9360152 TI - Flow analysis of the Cleveland Clinic centrifugal pump. AB - An implantable ventricular assist blood pump is being developed by the Cleveland Clinic Foundation in cooperation with the NASA Lewis Research Center. At the nominal design condition, the pump provides blood flow at the rate of 5 L/min at a pressure rise of 100 mmHg and a rotation speed of 3000 RPM. Bench testing of the centrifugal pump in a water/glycerin mixture has provided flow and pressure data at several rotative speeds. A one-dimensional empirically based pump flow analysis computer code developed at NASA Lewis Research Center has been used in the design process to simulate the flow in the primary radial pump stage. The computer model was used to size key impeller and volute geometric parameters that influence pressure rise and flow. Input requirements to the computer model include a simple representation of the pump geometry. The model estimates the flow conditions under design and off-design operating conditions at the impeller leading and trailing edges, and the volute inlet and exit. Output from the computer model is compared to flow and pressure data obtained from bench testing. PMID- 9360153 TI - A computer simulation study of isometric contraction of latissimus dorsi muscle used for cardiac assistance. AB - This study was designed to investigate the feasibility of a skeletal muscle pump employing latissimus dorsi muscle (LDM) for cardiac assistance. We developed and used a 2-dimensional mathematical model for LDM to investigate how the size of pneumatic balloons (30, 38, and 45 ml) and the three different locations (proximal, center, and distal) affect the pressure applied to the balloon by LDM. The computer simulation was performed by coding a visco-elastic and nonlinear 2 dimensional program that employed the finite element method (FEM). The muscle specific parameters of LDM were obtained from animal experiment results. The model is based on Hill's characteristic equation and composed of a contractile component and a passive element. The simulation results indicated that the intermediate and largest sized balloon lead to the highest and the lowest power (volume reduction per unit time interval), respectively. On the other hand, when the balloon is inserted in the distal LDM, the power is lower than in the other two positions, regardless of the balloon size. The above results suggest that the optimal size of the balloon should be selected depending on the muscle specific parameters of the actuator, and that the balloon should be inserted either in the proximal portion or center of the actuator. PMID- 9360154 TI - Cardiomyoplasty: hemodynamic benefit to normal and depressed canine left ventricular function. AB - This study examined the effects of cardiomyoplasty with vascular delay on canine normal and depressed left ventricular (LV) function. To improve viability of the latissimus dorsi muscle (LDM), vascular delay was performed 2 weeks before cardiomyoplasty in 10 mongrel dogs. Two weeks after cardiomyoplasty, LV function was evaluated by simultaneously measuring LV and aortic pressure, and aortic flow. The LDM was stimulated at a ratio of 1:4-1:7 synchronously with ventricular systole. Microspheres (90 mu) were sequentially injected into the left coronary artery to depress LV function. Data were acquired and analyzed on a beat to beat basis. Results were as follows: LDM stimulation significantly augmented LV systolic pressure (LVSP) from 138 +/- 2 to 161 +/- 2* mmHg, the peak rate of change of LV pressure (+dP/dt) from 1888 +/- 46 to 2584 +/- 43* mmHg/sec, aortic systolic pressure (AoSP) from 140 +/- 2 to 159 +/- 2* mmHg, stroke volume (SV) from 11.2 +/- 0.3 to 13.3 +/- 0.3* ml, stroke work (SW) from 19 +/- 1 to 26 +/- 1* gm.m, peak aortic flow (P Qa) from 5542 +/- 142 to 7190 +/- 161* ml/min, and decreased -dP/dt from -1683 +/- 31 to -1689 +/- 49* mmHg/sec (* = p < 0.05). Microsphere injections depressed LV function, but did not affect the magnitude of the net changes between stimulated and nonstimulated beats. However, the percent changes significantly increased. Preconditioning of LDM with vascular delay augments cardiac function in LDM assisted beats. This improved performance was present in both normal as well as depressed LV function groups. Thus, investigations of cardiomyoplasty may not necessarily require a model of severe myocardial dysfunction. Vascular delay offers an important preconditioning method of LDM to augment cardiac function in cardiomyoplasty. PMID- 9360155 TI - Innovative techniques in skeletal muscle cardiac assistance: first experimental study on minimally invasive aortomyoplasty and cardiomyoplasty. AB - Skeletal muscle cardiac assistance as a treatment modality for heart failure is considered a high-risk procedure subject to strict patient selection. The aim here is to develop minimally invasive techniques to improve surgical outcomes and increase clinical indications. Ten goats (45-55 kg) were studied. In six, the latissimus dorsi muscle (LDM) was harvested via an open technique on one side vs a minimally invasive technique on the other using video assistance through two 3 cm incisions. Surgical maneuvers and length of procedures were noted. Animals were recovered, observed daily for local complications, and killed after 1 week for comparative anatomic and histopathologic studies. In four other goats, minimally invasive aortomyoplasty or cardiomyoplasty was performed using video assistance (2 aortomyoplasty, 2 cardiomyoplasty). In this experimental series, there were no surgical complications. The minimally invasive LDM harvest required a mean of 81 min (range 55-116 mn) with no gross evidence of muscle damage. The technique of LDM harvesting was standardized and is reproducible. Aortic and cardiac wraping were also achieved through three ports and a left minithoracotomy of 4 cm, using the right or left LDM. A scarf technique for the descending aortomyoplasty using the left LDM, and an anterior wrapping for cardiomyoplasty using the left or right LDM was technically feasible with video assistance. This study suggests future clinical applicability. PMID- 9360156 TI - Clinical evaluation of the HeartPak. A new pneumatic portable driver for use with the HeartMate Implantable Pneumatic Left Ventricular Assist System. AB - The HeartPak Portable Pneumatic Driver was designed for use with the HeartMate Implantable Pneumatic Left Ventricular Assist Device (IP-LVAS) (Thermo Cardiosystems, Inc., Woburn, MA). The HeartPak measures 48 x 23 x 15 cm, weighs 9.3 kg with batteries, and can be carried by a handle, by a shoulder strap, or on a trolley. Four 12 V batteries provide power for as long as 8 hr. To test the HeartPak in the hospital environment, seven men were studied who were bridge-to transplant patients (mean age, 59.8 +/- 8.87 years) undergoing HeartMate IP-LVAS therapy. They were supported by the HeartPak for 429 days with a cycle count of 57,826,560. To normalize the mean pump flow rate, we used the body surface area to obtain a pump flow index in each case. The mean flow rate was 2.65 +/- 0.57 L/min/m2 for the HeartPak vs. 2.64 +/- 0.45 L/min/m2 for the HeartMate 1000, the conventional driver previously used in these patients. The only potentially serious problem with the HeartPak was console failure in one case. The patient took appropriate backup measures, and the HeartPak was replaced. In no case did the device cause any adverse effects or interruption of LVAS support. Compared with HeartMate 1000, the HeartPak was more convenient, easier to operate, and allowed better patient mobility. PMID- 9360157 TI - Assessment of timing right ventricular assist device withdrawal using left ventricular assist device filling characteristics. AB - Right ventricular assist devices (RVAD) are often needed on a short term basis in patients who develop RV failure after left ventricular assist device (LVAD) implantation. The purpose of this study was to use LVAD filling characteristics to help determine the timing for weaning a patient from RVAD support. Eleven patients (age 50 years +/- 15) supported with an LVAD (Novacor) and an RVAD (Biomedicus or ABIOMED) were studied. Eight patients (RV recovery group) were studied before RVAD removal and all were successfully weaned from RVAD support. Five patients (RV failure group) were studied at the time of RVAD placement to determine baseline characteristics of RV failure. Simultaneous measures of LVAD volume and routine hemodynamics were recorded during periods of high and low RVAD flow. The LVAD filling was assessed as the first derivative of LVAD volume and the mean filling rate for each cardiac cycle was calculated and averaged over 10 sec periods at both RVAD flows. The mean pump rate corrected filling rates did not change in the RV recovery group (89 +/- 13 vs. 87 +/- 8 ml/beat) and significantly decreased in the RV failure group (84 +/- 19 vs. 62 +/- 22 ml/ beat) (p < 0.001) with decreasing RVAD flow. These data suggest that LVAD filling rates may be used to assess RV systolic function and the proper timing of RVAD removal in selected patients. PMID- 9360158 TI - Parallel dialysis normalizes serum chemistries during venovenous perfusion induced hyperthermia. AB - Whole-body hyperthermia is currently under investigation as a method to treat systemic malignancies; however, available techniques induce a derangement in serum and urine chemistries. This study was done to determine whether veno-venous perfusion induced hyperthermia (vv-PISH) that incorporated a parallel dialysis system to control blood chemistries would eliminate these heat induced derangements. Adult female Yorkshire swine were divided into perfusion only (group P, n = 6, 62.8 +/- 2.5 kg), and perfusion with dialysis (group PD, n = 6, 63.8 +/- 4.3 kg). In both groups, hyperthermia was induced with a computer assisted jugular-to-femoral venovenous heat exchange/perfusion system primed with a balanced electrolyte solution, operating at 30 ml/min-1/kg-1, which used a thermal gradient induced by blood heated to a maximum of 48 degrees C and a perfusate-to-blood temperature gradient < 10 degrees C during heating. The target core temperature was 43 degrees C for 120 min as measured by the average of the rectal, bladder, esophageal, bilateral tympanic, and pulmonary artery temperatures. Including ramp-up and cool down, the total perfusion interval was 263 +/- 29 min in group P and 240 +/- 18 min in group PD (ns). Serum and urine chemistry values expressed as the mean value +/- SEM were compared before and after hyperthermia treatment. Variables include blood urea nitrogen, creatinine, sodium, potassium, chloride, calcium, magnesium, phosphorus, glucose, total protein, albumin, alkaline phosphatase (ALKP), creatinine kinase, aspartate aminotransferase, alanine aminotransferase (ALT), lactate dehydrogenase (LDH), plasma free hemoglobin, urine specific gravity, pH and urine creatinine. All variables remained within normal ranges for the PD group. In the P group, the following final values were outside the normal range: (normal range) creatinine 2.1 +/- 1 (0.4-1.4) mg/dl, Ca2+ 5.1 +/- 1 (6-13) mg/dl, Mg2+ .8 +/- 0.1 (1.2-10) mg/dl, ALKP 134 +/- 6 (34-122) U/L, ALT 69 +/- 3 (9-51) U/L, and LDH 1291 +/- 237 (300-600) U/L. We conclude that the significant changes in serum and urine chemistries associated with vv-PISH are normalized with the use of a parallel dialysis system and may decrease the incidence of electrolyte associated complications. PMID- 9360159 TI - Total respiratory support with tidal flow extracorporeal circulation in adult sheep. AB - A novel pressure gated tidal flow extracorporeal circulation (TF ECC) device was developed, and it was hypothesized that it could provide total respiratory support in apneic adult sheep without adverse hemodynamic or cardiac effects. The circuit consisted of a single lumen cannula, computer driven tubing occluders gated by circuit pressure, a nonocclusive peristaltic blood pump, a spiral coiled membrane lung, and a heat exchanger. Six paralyzed, anesthetized adult sheep were instrumented and TF ECC was instituted via cannulation of the right atrium. Total respiratory support was provided by the circuit during an apneic period of 6 hours. Echocardiography was performed with the animal instrumented (baseline) and after 2 hours of TF ECC. Circuit blood tidal volume was 172.6 +/- 18.0 cc, resulting in a TF ECC flow of 71.1 +/- 10.1 cc/kg/min. At the end of the study period, PaCO2 was 35.5 +/- 7.6 mmHg, paO2) was 91.2 +/- 30.6 mmHg, and pulmonary artery oxygen saturation (SPAO2) was 95 +/- 5%. Hemodynamic stability was maintained with no significant differences at baseline and after 6 hours in mean arterial pressure, mean pulmonary artery pressure, or heart rate noted. Echocardiographic evaluation showed preserved fractional shortening of the left ventricular (LV) septal-lateral dimension (baseline 32.4 +/- 11.4%; 2 hours 34.8 +/- 8.4%). This study demonstrates TF ECC provides total respiratory support without adverse hemodynamic effects, and preserved LV function. PMID- 9360160 TI - High flow/low resistance cannulas for percutaneous arteriovenous carbon dioxide removal. AB - Percutaneous cannulas with low resistance are necessary for arteriovenous carbon dioxide removal (AVCO2R) to allow highest flow at lowest pressure to maximize CO2 removal. Commercially available arterial (A) and venous (V) percutaneous cannulas (8-18 Fr) were tested for pressure/flow characteristics under conditions that simulated percutaneous AVCO2R at clinically pertinent flow rates between 200-1000 ml/min to obtain the M number previously described by Delius, et al. The Bio Medicus (Bio-Medicus, Grand Rapids, MI) 17F A, Research Medical, Inc (RMI) (Model FEM II, Research Medical, Inc., Midvale, UT) 16F A, and RMI 18F V cannulas exhibited the lowest M numbers that correlated with low resistance to flow. The four most clinically favorable arterial cannulas (8, 10, 12, and 14 Fr), coupled with a venous cannula four French sizes larger, were used in an AVCO2R circuit in adult sheep (n = 3) at varying mean arterial pressures (MAP) between 65-105 mmHg. The 8, 10, 12, and 14 Fr arterial cannulas allowed an arteriovenous flow of 208 +/- 72, 530 +/- 37, 848 +/- 66, and 944 +/- 96 ml/min, respectively, at a MAP of 65 mmHg. An increase in MAP to 105 mmHg was associated with approximately a 41, 30, 32, and 27% increment in blood flow, respectively. In summary, an arterial percutaneous cannula of 10 Fr or larger will allow AVCO2R blood flow greater than 500 ml/min, as previously shown by Brunston et al. to achieve total CO2 removal without incurring hypercapnia. PMID- 9360161 TI - Organ blood flow during arteriovenous carbon dioxide removal. AB - Animal models of arteriovenous carbon dioxide removal (AVCO2R) have achieved lung rest during treatment of severe respiratory failure, with total CO2 removal at arteriovenous shunt flow rates of 10% to 25% of cardiac output (CO). Previously, no statistically significant changes were reported in heart rate, cardiac output, mean arterial pressure, or pulmonary arterial pressure during prolonged (7 days) AVCO2R with shunt flows to 25% of CO. In this study, to determine the effect of various shunt levels on organ blood flow, colored microspheres were used in a conscious ovine model of AVCO2R. A low resistance 2.5 m2 oxygenator was placed in a simple carotid-to-jugular arteriovenous circuit. The AVCO2R flow (Qb) was incrementally increased to 5%, 10%, 15%, 20%, and 25% of baseline CO. After equilibration, colored microspheres were injected into a left atrial catheter while reference blood was withdrawn from an arterial line at a constant rate. Organ blood flow obtained by measuring microspheres in the tissues, showed approximately a 10-20% decrease at a 5% shunt, but remained relatively unchanged thereafter at up to a 25% shunt, and was well tolerated without hemodynamic sequelae or evidence of end organ ischemia. It was concluded that AVCO2R can achieve lung rest during respiratory failure at flow rates of 10-25% CO, with a resultant mild decrease in critical organ blood flow that appears well tolerated. PMID- 9360162 TI - Efficacy of a heparin removal device in comparison with protamine after hypothermic cardiopulmonary bypass. AB - To reduce the risks of protamine reactions after cardiopulmonary bypass (CPB), a heparin removal device (HRD) with plasma separation and poly-L-lysine (PLL) affinity adsorption was developed. To compare the efficacy of HRD with that of protamine, blood coagulation variables were evaluated in a swine model of CPB. Female Yorkshire swine were randomly divided into the HRD group (n = 6, weight 79.7 +/- 7.0 kg) and the protamine group (n = 6, weight 79.3 +/- 6.8 kg), and subjected to 60 min of right atrium-to-aortic, hypothermic (28 degrees C) CPB. After weaning from CPB, the right atrium was recannulated with a two-stage, dual lumen cannula in the HRD group. Blood flow was drained from the inferior vena cava, through the plasma separation chamber of the HRD where heparin was bound to PLL, and re-infused into the right atrium. The HRD run time was determined by an established mathematical model of first-order exponential depletion targeted to 90% heparin removal. In the protamine group, protamine was given in a 100 U heparin to 1 mg protamine ratio after CPB in a slow intravenous infusion. Hemodynamics, activated clotting time (ACT), activated partial thromboplastin time (APTT), and heparin concentration were obtained before, every 5 min during, and after the use of the HRD or before and after protamine administration, and 1 and 3 hours after HRD or protamine. Heparin concentration immediately after CPB was 4.90 +/- 0.19 U/ml in the HRD group and 3.94 +/- 0.63 U/ml in the protamine group, respectively (p > 0.05 between groups). The ACT was 994 +/- 7 sec in the HRD group and 768 +/- 55 sec in the protamine group, and APTT was greater than 150 sec in both groups (p > 0.05 between groups). In the HRD group, the HRD run time was determined to be 31.5 +/- 2.4 min for the targeted 90% heparin removal, and the plasma heparin concentration followed first-order depletion kinetics. In the protamine group, the full dose of protamine was administered over 15 min. Immediately after the HRD run or protamine administration, plasma heparin concentration decreased to 0.48 +/- 0.09 U/ml in the HRD group and 0.13 +/- 0.02 U/ml in the protamine group (p < 0.01 between groups); likewise, ACT decreased to 188 +/- 25 sec in the HRD group and 101 +/- 5 in the protamine group (p < 0.01 between groups). The APTT was not significantly different between the groups at any time during the experiment. Plasma heparin concentration and ACT were not significantly different three hours after the HRD run or protamine administration. The authors conclude that the HRD is capable of predictable reversal of systemic heparinization after CPB, and is an alternative to achieve heparin clearance in subjects who may develop adverse reactions to protamine. PMID- 9360163 TI - Extracorporeal whole body hyperthermia treatments for HIV infection and AIDS. AB - Whole body hyperthermia therapy (WBHT) is the elevation of the core body temperature to 42 degrees C. In vitro studies have confirmed that 42 degrees C is cytocidal for virally infected lymphocytes, and even more effective when heating is repeated 4 days later. The safety and efficacy of two successive sessions of WBHT (4 days apart) was evaluated in 30 patients with AIDS (not on protease inhibitors), randomized to: 1) untreated controls, 2) low temperature WBHT for 1 hour at 40 degrees C and repeated 96 hours later, and 3) high temperature WBHT for 1 hour at 42 degrees C and repeated 96 hours later. The sorbent suspension in the ThermoChem System (HemoCleanse, West Lafayette, IN) system automatically controlled blood phosphate, calcium, and other electrolyte concentrations during WBHT. In 1 year of follow-up after WBHT, there were positive effects of the therapy on frequency of AIDS defining events, Karnofsky score, and weight maintenance. However, effects on plasma HIV RNA and CD4 counts were transient. Two successive WBHT treatments were performed in four patients who were on protease inhibitor/triple drug therapy, but had suboptimal response. In follow-up for 6 months, plasma HIV RNA and CD4 improved after WBHT, and the patients remained clinically well. This WBHT may have specific advantages in patients with suboptimal response to protease inhibitor therapy. PMID- 9360164 TI - Effect of transaortic catheter venting on left ventricular function during venoarterial bypass. AB - Although venoarterial bypass (VAB) or percutaneous cardiopulmonary support (PCPS) can improve hemodynamics in patients with serious cardiac decompression, some cannot be weaned from circulatory support. Insufficient unloading of the left ventricle (LV) with blood stagnation is a main cause of unsuccessful LV recovery during PCPS. This investigation was undertaken to evaluate the effectiveness of transaortic catheter venting (TACV) for LV unloading. Eight mongrel dogs (mean weight 16.3 kg, range 14-20 kg) underwent VAB with TACV. In addition to monitoring standard hemodynamic parameters, the slope of the LV end systolic pressure-volume relationship (Emax) during transient occlusion of the inferior vena cava, the slope of LV end systolic pressure-stroke-volume (Ea), external stroke work (SW), LV pressure-volume area (PVA), and slope of the SW-end diastolic volume relationship (preload recruitable stroke work: PRSW) were assessed by means of a micro-tip manometer and a conductance catheter. We measured data under the following four conditions; before circulatory support (baseline), during isolated VAB, VAB with TACV, and VAB with TACV plus intra aortic balloon pumping (IABP). The LV contractility (Emax) and LV elastance (Ea) were equivalent for the four conditions. By comparison with baseline and VAB with TACV, LV energy (PVA) and work (SW, PRSW) were significantly reduced by TACV (1283.9 +/- 197.1 vs. 793.3 +/- 124.8 x 10(-4) J, 897.1 +/- 147.2 vs. 474.2 +/- 83.0 x 10(-4) J and 35.6 +/- 2.7 vs. 25.7 +/- 1.7 x 10(-4) J/ml, respectively), and the PE/PVA increased with TACV (30.4 +/- 2.6 vs. 40.8 +/- 1.8%). In contrast, there was no significant difference in PVA, SW, PRSW, and PE/PVA between baseline and isolated VAB. These results suggest that TACV might be an adjunctive technique to VAB or PCPS for patients with LV failure. PMID- 9360165 TI - An infection inhibiting urinary catheter material. AB - Catheter associated bacteriuria is a common infection in hospitals and nursing homes. An infection inhibiting catheter material for fabricating urinary catheters is being developed. The material consists of silicone rubber elastomer compounded with chlorhexidene gluconate (CHG) matrix. The antibiotic is released in sustained fashion over at least 4 weeks. A method was established for adding CHG to silicone rubber. To protect the CHG, it is suspended in a water soluble wax that also modulates CHG release from the elastomer. It was found that CHG is randomly dispersed in the elastomer and that the primary release mechanism is by diffusion. The antibacterial activity of the material with a range of 0.1 to 5% CHG by weight was examined using in vitro zone inhibition testing. The new material demonstrated significant inhibitory activity against three pathogens tested (Escherichia coli, Proteus mirabilis and Staphylococcus epidermidis.). The release rate of CHG was measured in vitro using high performance liquid chromatography (HPLC). With 5% CHG loading, the antibiotic was released at a steady rate of approximately 8.4 mg/cm2/day for periods extending beyond 4 weeks. This new material for urinary catheters has the potential to provide protection against infection and surface colonization. PMID- 9360166 TI - Rapid hepatocyte spheroid formation: optimization and long-term function in perfused microcapsules. AB - Enhancement of cell-cell interactions and, hence, long-term function in liver support systems can be effected by controlling the diameters of hepatocyte aggregates or spheroids. In this study, primary rat hepatocytes were induced to rapidly form spheroids using an intermittent settling and agitation protocol. The cells were seeded into albumin coated flasks at densities ranging from 80,000 to 520,000 cells/cm2. Hepatocytes were resuspended for 15 sec at 20-min intervals by placing the flasks on a timer controlled linear shaker. At time points ranging from 8 to 24 hr, hepatocyte aggregates were imaged via light microscopy. Mean spheroid diameter and shape factor were determined using computer analysis of captured images. Spheroid diameter could be controlled within the range of 60 to 240 microns. For long-term evaluation, spheroids were microencapsulated and cultured for 21 days under perfusion conditions. Encapsulated spheroids secreted albumin at rates comparable to collagen sandwich control cultures for at least 14 days, with peak rates (approximately 80 microns/day/10(6) cells) exhibited after culture medium changes. The results show that controlled, high efficiency hepatocyte aggregation can be accomplished in as little as 8 hr, and that the encapsulated spheroids exhibit long-term in vitro function. PMID- 9360167 TI - A novel wound dressing with an antibiotic delivery system stimulated by microbial infection. AB - The aim of this study was to develop a new wound dressing with controlled release of antibiotics only in the presence of infection. In the first experiment using an infected dorsal pouch of rats, exudate containing proteinases from pouches contaminated with Staphylococcus aureus or Pseudomonas aeruginosa showed significantly higher hydrolytic activity toward Boc-Val-Pro-Arg-MCA than that from noninfected wounds. The authors then developed a new type of wound dressing (AGX), a drug delivery system in which gentamicin is bound to polyvinylalcohol hydrogel through an enzymatically degradable peptide linker containing a -(D)-Phe Pro-Arg-sequence. To investigate in vitro effectiveness, AGX was incubated with exudate from S. aureus infected or P. aeruginosa infected wounds. Gentamicin was selectively released from AGX in the presence of the exudate from S. aureus infected or P. aeruginosa infected wounds, but was not released in the presence of exudate from noninfected wounds. Next, AGX or the polyvinylalcohol hydrogel that served as control was incubated with S. aureus in the presence of human plasma. After 24 hours, S. aureus concentration was markedly lower in the case with AGX than in that with polyvinylalcohol hydrogel. These results indicate that proteinases from wounds infected with S. aureus or P. aeruginosa cleaved the linker and gentamicin was released. PMID- 9360168 TI - Evidence that urea is a better surrogate marker of uremic toxicity than creatinine. AB - The protein equivalent of nitrogen appearance normalized to standard weight was determined from urea nitrogen appearance (nPNA U) and from total Kjeldahl nitrogen appearance (nPNA K) in dialysate and/or urine in 45 predialysis patients (pre D) and in 95 patients on continuous ambulatory peritoneal dialysis (CAPD). Correlations with weekly Kt/Vurea and creatinine clearance (Ccr, L/wk/1.73 m2) were determined; renal contributions of CCr in both populations were calculated both as total CCr (A) and as CCr by GFR (CCr [B], mean of renal CCr and Curea). Correlations with weekly Kt/Vurea were significant in individual (pre D:nPNA U 0.57, p < 0.01, and nPNA K 0.37, p < 0.01; CAPD:nPNA U 0.50, p < 0.01, and nPNA K 0.43, p < 0.01) and pooled populations (nPNA U 0.54, p < 0.01 and nPNA K 0.37, p < 0.01). Correlations with neither Ccr (A) nor Ccr (B) were significant. The data also allowed comment on mathematical coupling. Ccr vs nPNA K correlations share even more mathematical couplers than does the nPNA K vs Kt/Vurea correlation, yet the correlation of nPNA K with Ccr is quite low. The authors conclude that urea is a better surrogate marker of small molecular weight toxins that inhibit protein intake in uremia, and correlations of nPNA with Kt/Vurea represent more than simple mathematical coupling. PMID- 9360169 TI - Gender and racial disparity in peritoneal dialysis patients undergoing kidney transplantation. AB - Patients on dialysis who are women or minorities are less likely to receive a kidney transplant than are white men. Because the authors' renal program serves an inner city area and the majority of their patients are black, the authors retrospectively analyzed patients who were receiving peritoneal dialysis to see if that bias held true. Eighty-nine consecutive patients were studied. Sixty-one percent of the patients were women and 39% were men. The mean age was 47.4 years (range: 15-82 years). Sixty-seven percent of the patients were black, 17% were white, nine were Hispanic, and five were of Asian descent. Despite the preponderance of black and women patients, the majority of the 11 patients who received a kidney transplant were white (64%). Nine percent of the women were transplanted compared with 17% of the men. There was no significant difference in age between those patients who received a kidney transplant and those who did not. No assessment of comorbidity was done. The authors conclude that even in a program in which the majority of patients are black and women, white men are more likely to receive a renal transplant. PMID- 9360170 TI - Electrosurgical units. AB - Electrosurgical units (ESUs) have been used for decades for surgical cutting and hemostasis. In this study, we evaluate eight full-featured, high-power, solid state ESUs from four suppliers. We examined these units--all of which can be used for the vast majority of electrosurgical applications--for performance and safety, human factors design, and maintenance and durability. We found that all the evaluated units performed well in our testing and met our safety requirements; thus, we rated them all Acceptable. We did, however, identify a few noteworthy differences that separated some of the evaluated units from each other, as well as from the majority of units that have been in use for a decade or more. The most important of these factors were (i) the availability of new types of output modes (e.g., non-power-controlled modes, low-voltage modes) that produce differences in surgical effect and (2) the presence of certain characteristics and features (e.g., cutting modes with a broad power curve, programmable settings-memory features) that users indicated were helpful. Although we considered these distinguishing factors to be significant, we recognize that the full clinical impact of these developments has not yet been realized. And the ability of an institution to take advantage of any benefits such developments could offer will depend to a large degree on user technique. In this Evaluation, we also present a comprehensive overview of ESU technology; a Technology Management Guide, in which we offer strategies for managing the risks associated with electrosurgery; and an ESU Purchasing Guide, in which we offer guidance for determining the type and model of ESU that will best meet an institution's needs. In a future issue of Health Devices (scheduled for early 1998), we will be publishing an Evaluation of several moderate-power ESUs. These devices can be used for most of the same applications as the high-power units, but they cost much less. PMID- 9360171 TI - Medication errors associated with packaging and labeling of i.v. bags. PMID- 9360172 TI - Cover detachment and subsequent improvements to Rusch Flexi-Slip stylets. PMID- 9360173 TI - Variability in frame by frame analysis of left ventricular wall motion from contrast angiograms. AB - BACKGROUND: Measurement of the timing of left ventricular (LV) wall motion, of asynchrony, and of diastolic function from contrast angiograms requires delineation of the endocardial border frame by frame through the cardiac cycle. This study was performed to determine the magnitude of intraobserver and interobserver variability in manual border tracing, and to measure the impact of this variability on the derived functional parameters. METHODS: The contrast ventriculograms of 25 patients with coronary artery disease (CAD) or with normal coronary arteries were analyzed frame by frame, by two observers or twice by the same observer. Motion was measured using the centerline method at each twelfth of systole and of diastole. Variability was calculated as the absolute difference between repeated measurements of: wall motion, asynchrony, and the time at which each region of the LV reached 10%, 50%, and 100% of peak contraction, and 50% of filling. RESULTS: Intraobserver and interobserver variability in wall motion were similar, and varied with time in the cycle, and with location on the LV contour. Variability was highest at end systole, when it averaged 8% of the normal mean for wall motion. Variability in timing was highest at peak contraction; however, the variability in measuring asynchrony averaged only 18 msec. CONCLUSION: Analysis of the magnitude and synchrony of regional LV wall motion through the cardiac cycle from contrast ventriculograms can be performed with reproducibility comparable to that at end systole. PMID- 9360174 TI - Mortality related to diagnostic cardiac catheterization. The importance of left main coronary disease and catheter induced trauma. AB - BACKGROUND: The mortality of diagnostic catheterization is very low but still exists. Large series have documented left main disease as the most important anatomical risk factor but have not clarified the mechanism. OBJECTIVES: To determine the mortality of diagnostic catheterization in a single high volume centre over a 9 year period and assess any change during this period; to compare this experience with that of larger multicentre surveys; to identify the clinical and anatomical risk factors; to investigate the mechanism of the event; to develop guidelines for prevention METHODS: Cardiac catheterization records were reviewed over a 9 year period and patients dying during or within 24 hours were identified. The clinical and anatomical profile of the patients who died were compared with the overall group to search for independent risk factors. The angiograms of the deaths were reviewed for a mechanism. RESULTS: There were 30 deaths in 42,345 procedures (0.071%). There was no change in the incidence over the 9 years. Left main coronary disease was an overwhelming risk factor (incidence 0.7%, p < .002 compared to all other subgroups) and no other anatomical subgroup including triple vessel disease was at greater risk than the overall group. Dissection of the left main coronary artery by the diagnostic catheter was the mechanism of death in 20 cases (67%) CONCLUSIONS: Left main disease and catheter induced trauma are the most important risk factor for and mechanism of death during diagnostic catheterization and may account for the unchanging incidence. Technical guidelines are described which may reduce this risk. PMID- 9360175 TI - Reproducibility of stress echocardiography using intravenous injection of ultrasound contrast agent (BY 963). AB - Despite the widespread use of stress echocardiography, its reproducibility is still limited by high interobserver variability. Therefore, the purpose of the present study was to improve the reproducibility of a stress (exercise) echocardiography using a new transpulmonary ultrasound agent (BY 963). Stress echocardiography was performed in 12 healthy volunteers with suboptimal endocardial border delineation during exercise echocardiography. A special 45 degrees lateral tilted bike stress echocardiography table was used for exercise testing. Echocardiographic images were recorded on-line at rest and during exercise on a video tape and additionally digitized on-line on a stress echo computer. End-diastolic (EDVml), end-systolic (ESVml) volume and ejection fraction (EF%) were estimated in the 4-chamber view. The measurements were performed before and after injection of 2.5 ml and 5 ml BY963 at rest and in maximal exercise. A new contrast agent (BY 963) leads to a sufficient contrast effect for the left ventricular cavity after intravenous administration and permits a good delineation of left the endocardial border. The interobserver variability was determined using blinded investigation by two observers. The correlation of EDV and ESV determination at rest was r = 0.68/0.33, after 2.5 ml BY 963 r = 0.97/0.93 and after 5 ml BY 963 r = 0.90/0.93. The correlation for EDV and ESV during exercise was r = 0.52/0.33, after 2.5 ml BY 963 r = 0.88/0.80 and after 5 ml BY 963 r = 0.95/0.92. At rest mean EF without contrast was 61 +/- 6%/67 +/- 7% (r = 0. 130), after 2.5 ml BY 963 i.v. 69 +/- 8%/72 +/- 7% (r = 0.82) and after 5 ml BY 963 i.v. 73 +/- 8%/73 +/- 8% (r = 0.98%) respectively. In exercise, mean EF without contrast was 68 +/- 8%/70 +/- 6 (r = 0.013), after 2.5 ml BY 963 83 +/- 6%/81 +/- 5 and after 5 ml 83 +/- 4%/82 +/- 3 (r = 0.86). SUMMARY: The estimation of the end-systolic volume in exercise will be improved significantly and the estimated EF values will be higher compared to EF values obtained without contrast application. Transpulmonary contrast echocardiography for analysis of left ventricular volumes and ejection fraction can be routinely used in stress echocardiography. Intravenous administration of BY 963 improves the reproducibility of quantitative analysis of left ventricular function in healthy volunteers. Further studies in patients with cardiac diseases are required to corroborate this observation. PMID- 9360176 TI - The elusive link between coronary lesion morphology and dobutamine stress echocardiography results. The EDIC (Echo Dobutamine International Cooperative) Study Group. AB - BACKGROUND: Coronary lesion angiographic morphology of the complex type is associated to enhanced susceptibility to ischemia during vasodilator adenosinergic stress testing and attributed to the reduced vasodilatory capacity of the damaged endothelium. Whether coronary lesion morphology can also influence the results of adrenergic pharmacologic stress test remains unknown. The aim of our study was to assess the relationship between coronary plaque morphology and dobutamine-atropine stress echocardiography (DASE) results. METHODS AND RESULTS: We analyzed DASE (up to 40 mcg/kg/min plus atropine) and coronary angiography data of 42 patients with single vessel disease and no totally occluded vessel at angiography. 7 patients had angina, 35 had previous infarction. A diagnostic DASE was performed in all patients within 1-10 (mean 4.7 +/- 3.4) days before coronary angiography. An angiographic lesion was considered complex when irregular borders and/or intraluminal lucencies, suggestive of ulcer and/or thrombus were present. According to the angiographic lesion morphology (Ambrose classification), 2 groups were identified: Group I, with simple lesion; Group II with complex lesion. The two groups were similar for number of patients (n = 21), age (I = 55 +/- 11 vs II = 53 +/- 7 years, p = ns), coronary stenosis severity expressed as % diameter reduction (I = 77 +/- 14 vs II = 78 +/- 15%, p = ns), presence of previous infarction (I = 17 vs II = 18 pts, p = ns). No difference was found in the prevalence of positivity between the two groups (I = 72 vs II = 62%, p = ns). The two groups achieved a similar peak dobutamine dose (I = 32 +/- 9 vs II = 33 +/- 9 mcg/kg/min, p = ns) and peak Wall Motion Score Index (I = 1.5 +/- 0.26 vs II = 1.45 +/- 0.28, p = ns). CONCLUSIONS: In patients with non occlusive single vessel disease, coronary morphology of complex type is not associated with greater vulnerability to dobutamine induced ischemia. PMID- 9360177 TI - The differing prognostic utility of exercise radionuclide ventriculography in coronary artery disease patients with and without prior myocardial infarction. AB - Previous studies have documented the prognostic utility of left ventricular ejection fraction response to exercise primarily in populations without prior myocardial infarction. We undertook a study to assess the prognostic utility of exercise left ventricular ejection fraction and segmental wall motion response during exercise radionuclide ventriculography in coronary artery disease patients with and without prior myocardial infarction. METHODS: We examined the comparative prognostic utility of left ventricular ejection fraction and segmental wall motion response during upright bicycle exercise radionuclide ventriculography in 419 coronary artery disease patients with (n = 217) and without (n = 202) prior myocardial infarction using univariate and multivariate hierarchical regression analyses. RESULTS: During an average followup period of 61 months, 96 patients (23%) suffered cardiac events, including 55/217 (25%) of the patients with prior myocardial infarction and 41/200 (21%) of the patients without prior myocardial infarction (p = ns). Both cumulative Kaplan-Meier survival analyses and stepwise hierarchical Cox survival analyses demonstrated that peak left ventricular ejection fraction < 55% was a significant predictor of cardiac events in patients without prior myocardial infarction (p = 0.04), whereas an exercise wall motion worsening score > or = 2 was a significant predictor in patients with a prior myocardial infarction (p = 0.0001). CONCLUSIONS: The prognostic utility of exercise radionuclide ventriculography variables differ according to the presence or absence of prior myocardial infarction. Global function, assessed by peak left ventricular ejection fraction, adds the greatest prognostic information in patients without prior myocardial infarction, whereas regional function, assessed by exercise wall motion worsening, is the best predictor among patients with prior myocardial infarction. PMID- 9360178 TI - Myocardial perfusion imaging: clinical experience and recent progress in radionuclide scintigraphy and magnetic resonance imaging. AB - In the past 20 years, radionuclide scintigraphy has proven to be a sensitive clinical tool in the assessment of myocardial perfusion abnormalities. Magnetic resonance imaging may also be used to study myocardial perfusion, but its potential value still has to emerge in the clinical setting. This review addresses the potential and achievements of both methods in clinical cardiology. PMID- 9360179 TI - Magnetic resonance velocity mapping of normal transtricuspid velocity profiles. AB - To investigate the velocity profiles of transtricuspid inflow, we examined 20 normal subjects (17 males and 3 females, mean age 27 +/- 7) by the magnetic resonance imaging (MRI). Electrocardiographic gating was performed in all anatomical and flow studies, and sequences were triggered by the R wave. Cine gradient echo images (echo time, 14 ms) were acquired in the right ventricular horizontal long axis, and from these, cine images with velocity mapping were obtained in the short axis of the right ventricle. Velocity mapping of right ventricular inflow was obtained at peak early diastolic filling. Velocity profile curves across the tricuspid inflow were obtained at each 1 cm interval from the tricuspid ring to 3 cm into the cavity. Maximum/mean velocity was 1.1 +/- 0.1 at ring level, unchanged at 1 cm from the tricuspid ring, and thereafter increased to 1.4 +/- 0.3 at cm2, and 1.5 +/- 0.3 at 3 cm as peak velocity fell. The ratio of the longest and shortest jet width cross section was 1.3 +/- 0.3 at ring level, and increased to 1.5 +/- 0.3 at 3 cm from ring level. Jet cross sectional area was 10.4 +/- 2.1 cm2 at ring level, and was unchanged at 3 cm level. Thus, tricuspid inflow velocity showed a relatively flat profile at the tricuspid ring and tip level, becoming more dispersed at 2 and 3 cm from the ring. Right ventricular inflow jet cross section was elliptic, and appeared to be relatively constant in the cross-sectional area. PMID- 9360180 TI - Effects of serum from preeclamptic women on prostacyclin production by human endothelial cells. AB - There is growing evidence that proteinuric hypertension of pregnancy (preeclampsia) is associated with endothelial dysfunction. The aim of this study was to evaluate the effects of serum from preeclamptic patients on basal and agonist-stimulated prostacyclin production by human umbilical vein endothelial cells (HUVEC) in culture and to compare these to the effects of serum from normal pregnant and nonpregnant women. During a 24 h incubation of HUVEC with 20% of preeclampsia serum, baseline prostacyclin output was significantly (P < 0.01) increased over the control groups. However, this response was attenuated by extending the exposure to 72 h. Histamine, thrombin and the calcium ionophore, A23187, all acutely increased prostacyclin production, but the increase relative to baseline levels was greatest in HUVEC preincubated for 24 h in normal serum transiently promotes prostacyclin production in HUVEC derived from normal pregnancies, preeclampsia serum transiently promotes prostacyclin production in HUVEC derived from normal pregnancies, and 2) the relative increase in response to agonists is reduced by preeclampsia serum, compared to normal pregnancy sera. PMID- 9360181 TI - Value of umbilical artery and vein levels of interleukin-6 and soluble intracellular adhesion molecule-1 as predictors of neonatal hematologic indices and suspected early sepsis. AB - This study was designed to evaluate the relationship of suspected early neonatal sepsis to umbilical artery and vein levels of interleukin-6 (IL-6) and soluble intracellular adhesion molecule-1 (sICAM-1). Umbilical artery and vein samples from 17 preterm and 6 term pregnancies were assayed for IL-6 (pg/ml) and sICAM-1 (ng/ml). Neonates were categorized as having probable or suspected sepsis vs. no sepsis within 3 days of birth. Levels of IL-6 and sICAM-1 were evaluated based on sepsis status. Neonatal hematologic parameters were correlated with umbilical artery (ua) and vein (uv) levels of IL-6 and sICAM-1. Sensitivity, specificity, positive and negative predictive values for detecting neonates having probable or suspected early sepsis were calculated. There were significant differences of IL 6 levels between suspected sepsis and no infants in the umbilical artery (P < 0.002) and vein (P < 0.0001). The sensitivity, specificity, positive and negative predictive values for detection of suspected early neonatal sepsis using umbilical artery IL-6 levels > 7 pg/ml were 88.5%, 66.6%, 58.8%, 91%, and for umbilical vein levels > 7 pg/ml these values were 88.5%, 93.3%, 88.5%, and 93.3%. Umbilical artery and vein IL-6 levels correlated with both absolute band counts and immature/total neutrophil ratios. sICAM-1 levels were not affected by designated sepsis status. Umbilical cord blood IL-6 (but not sICAM-1) is potentially useful as a marker for suspected early neonatal sepsis. PMID- 9360182 TI - Cervical ripening: randomized comparison of intravaginal prostaglandin E2 gel with prostaglandin E2 gel plus laminaria tents. AB - The purpose of this study was to evaluate the efficacy of adding laminaria tents to sequential intravaginal prostaglandin E2 (PGE2) gel for cervical ripening. A prospective, randomized study was conducted from October 1994 to May 1995. Pregnant women with maternal or fetal indications for induction of labor at > or = 37 weeks gestation and a Bishop score of < or = 4 were eligible. Nineteen patients received laminaria tents in addition to 4 mg PGE2 gel, while 25 patients received PGE2 gel alone. After 4 hr, the laminaria tents were removed and the gel was continued in both groups at 4-hr intervals. Induction with oxytocin was initiated after a Bishop score of > or = 5 was achieved. The groups were comparable with respect to maternal age, parity, gestational age, reason for induction, and initial Bishop score. The addition of laminaria tents to sequential PGE2 gel did not statistically improve the time to a favorable cervix (control group 12.7 +/- 8.5 hr (95% CI, 9.1-16.3) and study group 10.9 +/- 7.1 hr (95% CI, 7.5-14.3) (P = 0.59). The 6-hr difference from the time of the initial PGE2 gel placement to delivery was not detected (control group 22.4 +/- 11.2 hr, 95% CI 17-27 and study group 23.4 +/- 13.1 hr, 95% CI 17-29.6 (P = 0.79). The combination approach of laminaria tents and PGE2 gel did not have a significant impact on the vaginal delivery rate, with 28.0% of patients in the control group and 26.3% of patients in the study group undergoing cesarean section (P = 0.90). Maternal and neonatal complications were rare in both groups. We had insufficient evidence to show that the addition of laminaria tents to PGE2 gel improved cervical ripening, the induction to delivery interval, or the cesarean section rate in patients at term undergoing induction of labor. PMID- 9360183 TI - Prolonged bedrest during pregnancy: does the risk of deep vein thrombosis warrant the use of routine heparin prophylaxis? AB - This is the first study to assess the risk of clinically apparent DVT in pregnant women placed in the hospital at prolonged bedrest. The outcome is discussed with reference to the risks associated with heparin. Information, including delivery data, length of hospital stay, and discharge diagnoses were extracted from a prospectively collected computerized data bank of all deliveries that occurred over a 5.5-year period at Long Beach Memorial Women's Hospital in Long Beach, California, and at St. Joseph's Hospital in Milwaukee, Wisconsin. One group consisted of all pregnant women who had been hospitalized at prolonged antepartum bedrest, as defined by 3 weeks or more. The other group consisted of the remaining population of women whose deliveries occurred during the same time period. There were 48,525 deliveries during the study period, and 266 (0.5%) women were hospitalized at prolonged antepartum bedrest. The mean number of days in the hospital for these women was 34.6 +/- 14 (range 21-82 days). Of these women, one received prophylactic heparin for a prior history of DVT. There were no cases of DVT in the 265 women who did not receive heparin, risk = 0.0 (CI = 0.00-0.99). Of these 265 women, 234 were hospitalized up to the day of delivery. Of these 234 women, 154 (65.8%) underwent cesarean section and no case of DVT occurred in the postoperative period, risk = 0.0 (CI = 0.0-1.7). Out of the remaining 48,259 women who were not hospitalized at prolonged bedrest, there were 18 cases of clinically apparent DVT, and the longest antepartum hospitalization was 4 days. A conservative risk of complications with prophylactic heparin therapy is 1.0% or greater. Although the risk of DVT in pregnant women hospitalized at prolonged bedrest is not zero, our study indicates that it is very low (< 1.0%). Whereas a risk of DVT of at least 1.0% could warrant heparin prophylaxis, even with 265 patients at prolonged bedrest and 48,525 controls, this risk could not be demonstrated. Using a power analysis with an alpha of 0.05 and a power of 80% to demonstrate this risk, one would need 247 cases and approximately 49,000 controls, which were clearly achieved in this study. In view of the risks associated with heparin, routine antenatal prophylaxis is not recommended unless other risk factors for DVT are present. PMID- 9360184 TI - Outcomes of high-order multiple implantations in women undergoing ovum donation. AB - Increasing numbers of young women with ovarian failure and women of advanced reproductive age (> 40 yrs) utilize oocyte donation to treat their infertility. In both groups, women who become pregnant frequently experience multiple gestation, occurring in up to 30% of pregnancies. Advanced maternal age and high order multiple gestations are associated with an increased risk for obstetric complications. We reviewed the pregnancies of patients with high-order multiple gestations (> or = 3 gestational sacs) with respect to their antepartum course and neonatal outcomes. Mothers were divided into two groups according to age at conception; Group I (> or = 40 yr, n = 20) and Group II (< 40 yr, n = 10). These 30 high-order multiple gestations were found among 127 successful oocyte donation cycles (23.6% of all pregnant patients). Data regarding pregnancy outcomes were gained by chart review and telephone interview. Results demonstrated spontaneous reductions in the number of implantation sites were similar between groups (Group I: 21.4% vs. Group II: 17.6%). Multifetal pregnancy reduction (MFPR) was more often chosen by older women (Group I: 45% vs. Group II: 10%; P < 0.05). Antenatal complications were commonly experienced by both groups (> 80%) as were operative deliveries (> 85%). However, neonatal outcomes were generally good, with only one death occurring in the 79 delivered infants (1.3%). We conclude transferring supernumerary embryos to women undergoing ovum donation places patients at great risk for high-order multiple gestations. These pregnancies are associated with increased antenatal and neonatal complications. Although advanced maternal age is normally an added risk factor, well-screened older patients carrying high-order multiple gestations experienced similar outcomes as younger mothers. PMID- 9360185 TI - Antenatal sonographic diagnosis of dacryocystocele. AB - Dacryocystocele is an uncommon condition presenting at birth as a bluish swelling approximately 1 cm in diameter located below and nasal to the medial canthus. It represents a cystic swelling of the lacrimal sac due to obstruction of the lacrimal drainage system both above and below the sac. The average age when the lacrimal duct becomes patent is the eighth intrauterine month. If this does not occur, a dacryocystocele can result. Dacryocystocele is also referred to in the literature as mucocele, dacryocele, and amniocele of the lacrimal sac. We report a case of a dacryocystocele detected sonographically during pregnancy. PMID- 9360186 TI - Effect of modern obstetrics on mothers from Third-World countries. AB - Mothers born and raised in third-world countries compared to women born in the United States are on average of shorter size, have less weight, have narrower pelvic dimensions, and give birth to smaller infants without much difficulty. This may be due to a low-protein diet and inadequate prenatal care. Those mothers who were born and raised outside the United States (therefore with narrow pelvic dimensions), but who eat a high-protein diet and receive adequate prenatal care after migrating as adults to the United States, give birth to relatively large infants. This results in a marked cephalopelvic disproportion and severe dystocia, which frequently leads to cesarean birth. It appears that nutritional factors during pregnancy and infancy play a role as important as genetic factors in the etiology of cephalopelvic disproportion. PMID- 9360187 TI - Prevalence of fetal heart rate decelerations in self-referred low-risk patients in the third trimester. AB - We tested the hypotheses that fetal heart rate decelerations are present during the third trimester in most low risk pregnant women, the prevalence of decelerations is a function of the length of time fetal heart rate monitoring occurs and their presence is not associated with an adverse prognosis. We performed a retrospective chart review of 114 self-referred low-risk pregnant patients who presented to the labor and delivery triage area of a tertiary care hospital at 26-41 weeks gestation. None required admission to the hospital. The control group consisted of patients who delivered immediately before and after the delivery of the study patient. Normal long-term variability and fetal baseline heart rate were found in all electronic fetal monitoring tracings. Accelerations were present in 91% and decelerations in 65% of patients. There was no correlation between length of time of monitoring and the incidence of decelerations. At delivery, there were no differences in birthweight, gestational age, 5-min Apgar scores or cord pH between the control and study patients. Variable decelerations were a common finding in the third trimester of low-risk pregnant patients who self referred to labor and delivery triage. They were not prognostic of an adverse perinatal outcome. PMID- 9360188 TI - Relative importance of maternal constitutional factors and glucose intolerance of pregnancy in the development of newborn macrosomia. AB - The purpose of this case-control study was to determine the relative importance of various predictors of newborn macrosomia, with particular reference to maternal constitutional factors and glucose intolerance of pregnancy. Macrosomia was defined by both absolute birthweight > or = 4,000 g and birthweight > or = 90th centile for gestational age. One thousand mother/newborn pairs [209 macrosomic (cases) and 791 non-macrosomic newborns (controls)] were recruited. Mothers with pre-gestational diabetes mellitus were excluded. Data on pregnancy and pregnancy variables were collected by review of prenatal, labour, and delivery and newborn assessment records and interview with the mother. Predictors that entered the stepwise multiple regression model in order of significance were: previous history of macrosomia, increasing maternal weight, nonsmoking status, multiparity, male newborn gender, gestational age of 40-42 weeks, North American Aboriginal ethnicity, maternal birthweight > 4,000 g, maternal height and maternal age < 17 years. Glucose screen positive/100-g oral glucose tolerance test (GTT) negative status was a significant predictor for macrosomia as defined by birthweight greater than the 90th percentile for gestational age, but not for absolute birthweight over 4,000 g. It was the least significant of all the factors examined. Treated gestational diabetes was not a significant predictor. By multivariate analysis, maternal constitutional factors are more powerful predictors of newborn macrosomia than maternal mild glucose intolerance. Treatment of mothers with GDM may be masking the effect of more pronounced carbohydrate intolerance. PMID- 9360189 TI - Anthropometric measurement of newborns of gestational diabetic mothers: does it indicate disproportionate fetal growth? AB - Anthropometric and skinfold measurements in 51 newborns of mothers with gestational diabetes were compared to reference ranges obtained from measurements of 501 newborns of nondiabetic mothers. In newborns of diabetic mothers, the means of fetal birth weight, biceps, subscapular, suprailiac skinfolds, and total fat index measurements (the sum of all measurements) were significantly greater than those of the nondiabetic group. While the means of fetal crown-heel length and head circumference did not significantly differ between the two groups, these findings suggest a disproportionate pattern of growth in fetuses of diabetic mothers, with increased tendency for deposition of subcutaneous fat. The studied population were then stratified into six categories according to birth weight percentiles. Within each category, the skinfold measurements in newborns of diabetic mothers were greater--though the difference was not statistically significant than that of nondiabetic mothers. It is possible, however, that in severe cases of maternal diabetes, the risks of complications, such as shoulder dystocia, increase with disproportionate deposition of subcutaneous fat. These risks appear greater than in fetuses of nondiabetic mothers at a comparable birthweight. PMID- 9360190 TI - Magnesium tocolysis as the cause of urinary calculus during pregnancy. AB - Twenty-one days of magnesium sulfate tocolysis were performed on a 28-year-old woman because of preterm labor at 31 weeks gestation. In association with this tocolysis, urinary calculus of magnesium ammonium phosphate occurred at 34 weeks gestation. PMID- 9360191 TI - Requiem for a heavyweight: the demise of scalp blood pH sampling. AB - Fetal scalp blood pH sampling has played a valuable role in the development of our understanding of fetal welfare in labor and in the interpretation of electronic fetal heart rate patterns. There is question as to the feasibility of retaining this practice in modern obstetric care because of the advance of science, the general reliance on fetal monitoring criteria for ascertaining fetal well-being, the logistic difficulties involved in obtaining accurate and timely samples, the economic consequences of having to maintain analytic equipment in working order in times of very infrequent use, and the poor correlation between pH alterations and predictable neurologic consequences in the child. As it has all but vanished from use in most clinical care centers, and the principal argument for retaining it ultimately references the physician as the beneficiary, the author proposes that it should be removed from any possible association with purported "standards of care." PMID- 9360192 TI - Increased nuchal translucency thickness in a fetus at risk for beta-thalassaemia. AB - In Greece and other Mediterranean countries up to 10% of the population are carriers of beta-thalassaemia and this is the most common indication for chorion villus sampling (CVS): Cytogenetic analysis of the samples is not carried out routinely, but is confined only to women aged 35 years or more. In this report we present a case that illustrates how the measurement of fetal nuchal translucency may be useful in selecting the cases where in addition to the DNA analysis for beta-thalassaemia the samples can be tested for chromosomal defects. PMID- 9360193 TI - Association between polycystic ovary syndrome and glucose intolerance during pregnancy. AB - The purpose of our study was to determine if women with polycystic ovary syndrome are more likely than other women with infertility to develop gestational diabetes. All women who were successfully treated for infertility in the reproductive endocrinology clinic at the University of Arizona Health Sciences Center from January 1, 1990, to January 1, 1995, were identified. A retrospective cohort study was performed comparing the incidence of gestational diabetes and abnormal diabetic screening tests among subjects with polycystic ovary syndrome (N = 24) and a general infertility control group (N = 44). The incidence of gestational diabetes diagnosed in subjects with a history of polycystic ovary disease was similar to the incidence of gestational diabetes in subjects with infertility not ascribed to polycystic ovary disease (four subjects, 16.7% v. three subjects, 6.7%; relative risk [RR] 2.05, 95% confidence interval [CI] 0.31 13.57). A greater number of subjects with polycystic ovary syndrome had a positive diabetic screening test compared to the control group (13 subjects, 54% v. 10 subjects, 23%; RR 2.44, 95% CI 1.26-4.71). Our study suggests that women with polycystic ovary syndrome are more likely to have a positive diabetic screening test, but no more likely to have gestational diabetes than other women with infertility. PMID- 9360194 TI - The status of the embryo and policy discourse. PMID- 9360195 TI - Fetal status: sources and implications. AB - This essay considers the ways in which the various contexts--abortion, prenatal diagnosis, fetal research, and the use of fetuses in transplantation--shape the American debate on the moral standing of the fetus. This discussion gives rise to several philosophical debates on the status of the preimplantation embryo, particularly the debate over when the preimplantation embryo becomes individuated. How that question is resolved has critical ethical and policy implications. PMID- 9360196 TI - Embryo research and public policy: a philosopher's appraisal. AB - The development of public policy on bioethical issues can be approached through substantive moral and philosophic reasoning, or through balancing perceived societal views as to what is ethically acceptable. The Human Embryo Research Panel had to apply the first approach to the question of the moral status of the preimplantation embryo. Only after concluding that the preimplantation embryo was not a full human subject could the panel consider the conditions under which embryo research was ethically acceptable, given a range of societal views, concerns, and interests. PMID- 9360197 TI - Embryo research: the challenge for public policy. AB - Complete moral consensus on the status of the human embryo is neither feasible nor necessary for the formulation of ethically acceptable public policy for human embryo research. Significant consensus on permissible human embryo research can rest upon diverse but overlapping moral traditions. Thus, human embryo research policy should do more than reflect mere abstract assertions about the moral status of human embryos. Rather, the moral underpinnings of human embryo research should be derived from a range of values, including the facilitation of human procreation, the advancement of applied scientific knowledge, the reduction of human suffering, and the protection of vulnerable persons from coercion and exploitation. PMID- 9360198 TI - The moral status of preembryos, embryos, fetuses, and infants. AB - Some have argued that embryos and fetuses have the moral status of personhood because of certain criteria that are satisfied during gestation. However, these attempts to base personhood during gestation on intrinsic characteristics have uniformly been unsuccessful. Within a secular framework, another approach to establishing a moral standing for embryos and fetuses is to argue that we ought to confer some moral status upon them. There appear to be two main approaches to defending conferred moral standing; namely, consequentialist and contractarian arguments. This article puts forward a consequentialist argument for the conferred moral standing of preembryos, embryos, fetuses, and infants. It states and defends an original version of the commonly-held view that moral standing increases during gestation. It also explores the implications of this viewpoint for several issues: what is involved in showing 'respect' for preembryos; and whether it is permissible to create preembryos solely for research. PMID- 9360199 TI - Persons, practices, and the conception argument. AB - The argument that human life should be fully protected once conception is complete has been challenged by the claim that at that time such life is not genuinely individuated in the morally required sense. This essay analyzes the "conception versus individuation" exchange and directs attention to the communal contexts within which the relevant arguments and counter-arguments arise. PMID- 9360200 TI - Embryo research: the ethical geography of the debate. AB - Three basic political positions on embryo research will be identified as libertarian, conservative, and social-democratic. The Human Embryo Research Panel will be regarded as an expression of the social-democratic position. A taxonomy of the ethical issues addressed by the Panel will then be developed at the juncture of political and ethical modes of reflection. Among the arguments considered will be those for the separability of the abortion and embryo research debates; arguments against the possibility of the preembryo being a person, especially arguments associated with totipotency and the significance of the primitive streak; and the various reasons for regulating embryo research, including those associated with respect for the preembryo, the protection of traditional views of human procreation, and the prevention of commercialization. PMID- 9360201 TI - Percutaneous endoscopic gastrostomy in children and adolescents. AB - BACKGROUND: Long-term nasogastric tube feeding is often associated with irritation of the hypopharynx or dislocation of the tube. These pitfalls may be circumvented by percutaneous endoscopic gastrostomy. Although frequently used in adults, there is limited experience with the procedure in children. METHODS: A series of 139 patients (aged 3 weeks to 36.5 years, mean age, 4.4 years; weight 3.1-60 kg, mean weight, 15 kg) underwent placement of a percutaneous endoscopic gastrostomy because of central dysphagia (n = 103); general dystrophy caused by chronic renal failure, congenital heart disease, neoplasms, or cystic fibrosis (n = 26); requirement for special diets (n = 7); malnutrition related to respiratory insufficiency (n = 2); and gastric volvulus (n = 1). RESULTS: The percutaneous endoscopic gastrostomy was placed either in the stomach (n = 122) or in the duodenum (n = 15). In two patients a direct percutaneous endoscopic jejunostomy was performed, because duodenal placement proved impossible. Percutaneous endoscopic gastrostomies were placed using intravenous sedation (midazolam, etomidate, or diazepam). None of the patients required general or inhalation anesthesia. We observed 19 complications including: dislocation of the duodenal part into the stomach (n = 5); inflammation at the insertion site (n = 3); perforation of the stomach (n = 2), which healed under conservative treatment; disconnection of the retention disk (n = 4); occlusion of the tube (n = 4), and chronic vomiting (n = 1). Mean lifetime of a percutaneous endoscopic gastrostomy was more than 1 year. CONCLUSIONS: Percutaneous endoscopic gastrostomy provides a major improvement for children requiring long-term tube feeding. High efficacy and low rates of complication suggest that percutaneous endoscopic gastrostomy should be considered more often, even in infants. PMID- 9360202 TI - Gastric emptying time is faster in cystic fibrosis. AB - BACKGROUND: The high energy requirements in cystic fibrosis (CF) increase the likelihood of malnutrition. Delayed mouth-to-cecum transit times have been reported and raise the possibility that abnormalities of gastric function in CF contribute to reduced food intake. The aims of this project were to document solid-phase gastric emptying times in young people with CF and age- and sex matched healthy controls, and to investigate whether delayed gastric emptying contributes to suboptimal energy intakes. METHODS: Nineteen subjects with CF, mean age 12.6 years (11 girls and 8 boys), and 17 control subjects, mean age 12.8 years (9 girls and 8 boys), were studied. Energy intake was assessed by means of a 4-day weighed food record. Fecal fat excretion was determined from a 3-day stool collection. Gastric emptying was assessed with a standard test meal of pancakes labeled with 99mTc-macroalbumin aggregates. The half emptying time of solids from the stomach was recorded. RESULTS: The mean solid-phase gastric emptying time was significantly faster in the CF subjects compared with normal, healthy, age- and sex-matched control subjects (53 min vs. 72.2 min, p < 0.05). Energy intakes, measured as the percentage of the recommended energy intake for age and sex, were greater in the CF subjects than in the control subjects (115% vs. 89%, p < 0.01), whereas the mean % FFE for the CF subjects was 9.9%. CF subjects with longer gastric emptying times also had lower relative energy intakes (r = -0.50, p < 0.05). CONCLUSION: Gastric emptying time in healthy subjects with CF is rapid. Faster solid-phase gastric emptying times may be secondary to high-fat, high-energy intakes and may represent a survival advantage. PMID- 9360203 TI - Cisapride in pediatric gastroesophageal reflux. AB - BACKGROUND: Gastroesophageal reflux is a common condition that in infants may lead to serious complication. This study assessed the efficacy and safety of oral cisapride suspension in the treatment of children 6 weeks to 2 years old with daily regurgitant reflux. METHODS: A randomized, prospective, double-blind, placebo-controlled clinical trial was conducted at three study sites. After a 1 week baseline assessment, 45 infants 6 weeks to 2 years old were randomized to a double-blind trial in which they received a 6 week course of cisapride (0.2 mg/kg q6h) or a placebo suspension. Efficacy was assessed with 24 hour esophageal pH monitoring, esophageal manometry, and esophageal biopsy before and after the treatment period. A diary of regurgitation frequency and severity was kept by the parents. Safety was assessed by adverse event monitoring and standard laboratory measurements. RESULTS: Compared with placebo, cisapride significantly (p < 0.05) reduced the mean duration of upright and supine reflux episodes. Compared to baseline, cisapride significantly reduced the mean duration of the longest reflux episode, and placebo increased the mean number of reflux episodes longer than 5 minutes. Cisapride was not significantly different from placebo for the following mean measurements: percent of total time pH < 4, number of reflux episodes, lower esophageal sphincter pressure, swallow pressure, regurgitation frequency or global evaluation scores. CONCLUSIONS: Cisapride is a safe, well tolerated prokinetic agent that improves the esophageal clearance of refluxed gastric acid in children under the age of 2 years. PMID- 9360204 TI - Nutritional factors and Helicobacter pylori infection in Colombian children. AB - BACKGROUND: Helicobacter pylori infection occurs most frequently in impoverished populations; however, little is known about specific determinants of susceptibility. This report describes the relationship between H. pylori infection and nutritional indicators among children from a rural village in the Colombian Andes, where a prevalence of 69% was observed in children from 2 to 9 years old. METHODS: In a cross-sectional study of 684 children, comprising 92% of the 2- to 9-year-old population of Aldana, Colombia, information was obtained on dietary factors by questionnaire, height and weight by direct measurement, and H. pylori status using the carbon-13 urea breath test. Multivariate logistic regression was used to estimate relative risks for nutritional indicators. RESULTS: The infection was least frequent among children who are several servings of fruits and vegetables daily, drank two or more cups of milk daily, and were in the upper quintile of height for their age. The odds of infection increased 19 fold (95% confidence interval, 4.0-91.9) among children who consumed less than two daily servings of fruits and vegetables compared with the modal intake of three to five daily servings. Children whose daily vitamin C intake from fruits and vegetables was less than 40 mg had greatly increased odds of infection (odds ratio, 7.2; 95% confidence interval, 1.5-34.1) compared to the modal intake of 80 119 mg; for beta-carotene, the odds ratio was 3.1 (95% confidence interval, 1.2 7.9) for intakes of less than 300 IU per day, compared with the modal daily intake of 900 IU or more. CONCLUSIONS: The results of this population-based study suggest that nutritional factors may play a role in determining susceptibility to H. pylori infection. PMID- 9360205 TI - Oral bacterial therapy reduces the duration of symptoms and of viral excretion in children with mild diarrhea. AB - BACKGROUND: Oral administration of live Lactobacillus casei strain GG is associated with the reduction of duration of diarrhea in children admitted to the hospital because of diarrhea. The purposes of this work were to investigate the clinical efficacy of oral administration of Lactobacillus in children with mild diarrhea who were observed as outpatients, and to see whether Lactobacillus GG can reduce the duration of rotavirus excretion. METHODS: Duration of diarrhea was recorded in 100 children seen by family pediatricians and randomly assigned to receive oral rehydration or oral rehydration followed by the administration of lyophilized Lactobacillus casei, strain GG. Rotavirus was looked for in the stools of all children and in those in whom results were positive, stools were examined again 6 days after the onset of diarrhea. RESULTS: In 61 children results were positive for rotavirus and in 39 results were negative. Duration of diarrhea was reduced from 6 to 3 days in children receiving Lactobacillus GG, with a similar pattern in rotavirus-positive and -negative children. Six days after the onset of diarrhea, stools in only 4 out of 31 children that received Lactobacillus GG were positive for rotavirus compared with positive findings in 25 out of 30 control subjects. CONCLUSIONS: Oral administration of Lactobacillus GG is effective in rotavirus-positive and rotavirus-negative ambulatory children with diarrhea. Furthermore, it reduces the duration of rotavirus excretion. PMID- 9360206 TI - Extrahepatic portal vein obstruction in children: anthropometry, growth hormone, and insulin-like growth factor I. AB - BACKGROUND: Extrahepatic portal vein obstruction has been shown to cause growth retardation in children, though literature is scant. No information is available regarding the cause of growth retardation in these patients. METHODS: To document the presence of growth retardation in this disease, we studied growth and nutrition in 33 consecutive prepubertal patients. Anthropometry, fasting growth hormone, and insulin-like growth factor I levels were compared in 22 well nourished patients from this group with 35 age-matched well-nourished controls. RESULTS: Mean +/- SD height standard deviation score of well-nourished patients ( 1.88 +/- 1.33) was significantly below that of the controls (-1.06 +/- 0.64, p < 0.01). Patients also had significantly lower midarm muscle circumference z scores (-2.65 +/- 1.09) than controls (-1.17 +/- 1.09, p < 0.0001), though triceps skinfold thickness z scores were comparable in the two groups (-1.06 +/- 0.68 vs 1.24 +/- 0.79, p = NS). Insulin-like growth factor I z scores were significantly lower in patients (-1.48 +/- 0.88) than in controls (-0.49 +/- 1.09, p < 0.001), whereas basal growth hormone was significantly higher in patients (4.60 +/- 3.70 mIU/L) compared with controls (2.66 +/- 0.82, p < 0.01). CONCLUSION: Extrahepatic portal vein obstruction in children leads to growth retardation. Anthropometric and preliminary hormonal evaluation suggest resistance to the action of growth hormone as a possible mechanism. PMID- 9360207 TI - The technetium white cell scan as an initial imaging investigation for evaluating suspected childhood inflammatory bowel disease. AB - BACKGROUND: The technetium white cell scan (WCS) may be a useful investigation for patients with inflammatory bowel disease (IBD). In a retrospective study we assessed the use of the WCS as an initial imaging investigation in evaluating children with suspected IBD. METHODS: Over a 3-year period, 60 WCS were performed on 55 patients (25 boys, median age 12.1 years, age range 1.5-18 years) with known or suspected IBD. There were two clinical groups: those with previously diagnosed IBD (histologically and radiologically) and in clinical relapse (13 patients), and newly presenting patients with suspected IBD (42 patients). RESULTS: Eighteen scans were performed on the 13 patients presenting with relapse. Seventeen were positive and one patient, subsequently shown to have an inactive stricture, had a negative scan. Seven of the 42 newly presenting patients had abnormal scans, confirmed to be due to IBD by a combination of histology and barium examinations. Of the remaining 35 scans, three were abnormal and 32 were normal. None of these patients were subsequently proven to have IBD. These results show that in detecting active IBD, a positive WCS has a 100% sensitivity (24/24) and a 91% specificity (32/35) in the diagnosis of IBD. CONCLUSIONS: Our results show that the WCS is very useful as an initial imaging investigation in evaluating patients with suspected IBD to select patients for further investigation. PMID- 9360208 TI - Whey deionization method of infant formula affects plasma lipids. AB - BACKGROUND: Casein has proved to be hypercholesterolemic. According to results of previous studies, the casein-to-whey ratio in infant formula influences plasma lipid profile. This study explored whether different methods of whey deionization also affect levels of plasma lipids. METHODS: Two types of a whey-predominant (whey 60%:casein 40%) formula which differed only in the methods used for whey deionization (ultrafiltration or electrodialysis), were fed to healthy newborn infants for 60 days, using a prospective, double-blind, randomized design. Formulas were otherwise identical in composition. RESULTS: Groups were similar in gestational age, gender, birth weight, and growth parameters. Evaluation of fasting plasma levels after 60 days revealed significantly higher values of total cholesterol (p < 0.001) and low-density lipoprotein cholesterol (p < 0.001) in infants fed ultrafiltrated whey compared with the same values in infants fed electrodialyzed whey. Plasma levels in the two groups of very low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides revealed no statistically significant differences. CONCLUSIONS: Plasma lipid profile in infancy is influenced by dietary protein, not only by the casein-to whey ratio, but also by the method of whey deionization. PMID- 9360209 TI - Multiple cerebral venous thromboses in a child with inflammatory bowel disease. PMID- 9360210 TI - Hyperammonemia after chemotherapy in an adolescent with hepatocellular carcinoma. PMID- 9360211 TI - Neutral lipid storage disease with fatty liver and cholestasis. PMID- 9360212 TI - Frequency and medical management of esophageal perforation after pneumatic dilatation in achalasia. PMID- 9360213 TI - Excessive fruit juice consumption: how can something that causes failure to thrive be associated with obesity? PMID- 9360214 TI - Tumor necrosis factor-alpha and interleukin-6 in stools of children with bacterial and viral gastroenteritis. PMID- 9360215 TI - Is extrahepatic biliary atresia an HLA-associated disease? PMID- 9360216 TI - Spinal cord repair strategies: problems and prospects. PMID- 9360217 TI - A review: frustrations and needs in clinical care of spinal cord injury patients. PMID- 9360218 TI - Entry rate kinetics of D-mannitol and carboxyl-inulin for transfer across the blood-cerebrospinal fluid barrier. AB - This study evaluates the entry rate kinetics of hydrophilic compounds [3H]-D mannitol and [14C]-carboxyl-inulin across the blood-cerebrospinal fluid (CSF) barrier in a rabbit experimental model. To maintain steady state levels of these tracers in circulation, 100 microCi of [3H]-D-mannitol and 150 microCi of [14C] carboxyl-inulin were administered as a bolus and by slow infusion for four hours via a femoral venous catheter. Entry rate kinetics of [3H]-D-mannitol and [14C] carboxyl-inulin from plasma into cisterna magna CSF were computed using a mathematical equation described by Davson. [3H]-D-mannitol and [14C]-carboxyl inulin maintained steady state levels throughout the experiment. Entry rates for mannitol and carboxyl-inulin were represented by a straight line, from the slope of which K(out) (or K(in)) were computed: K(in) values for mannitol and carboxyl inulin were 0.06820 hr(-1) and 0.00023 hr(-1), respectively. Differences in the entry rate of mannitol and carboxyl-inulin may be explained by the molecular size and effective radius of these tracers. PMID- 9360219 TI - Transcranial magnetic stimulation: use of motor evoked potentials in the evaluation of surgically induced spinal cord ischemia. AB - We evaluated transcranial magnetic stimulation producing motor evoked potentials (TMS MEP) as a method to detect spinal cord ischemia during surgery for thoracoabdominal aneurysms. Four groups of swine were subjected to different types of surgically-induced ischemia. TMS MEP and neurological function were assessed at baseline, immediately after the ischemic insult and after four hours of reperfusion/post-ligation. Cross-clamping of the aorta in groups A&B resulted in the disappearance and subsequent reappearance of TMS MEP with significantly prolonged latencies in most animals and variable neurological function. Ligation of intercostal arteries produced no changes in TMS MEP or neurological function (group C). However, after ligation of intercostal and lumbar arteries, group D demonstrated no reappearance of TMS MEP and severe neurological deficits. TMS MEP can provide rapid detection of global spinal cord ischemia and can also predict local devascularization injury. PMID- 9360220 TI - A comparison of low molecular weight heparin and low dose unfractionated heparin prophylaxis in subacute myelopathy. AB - Deep vein thrombosis (DVT) and pulmonary embolism (PE) are common life threatening complications of acute myelopathy. Prophylaxis with low dose unfractionated heparin (LDUH) has been the standard of care. Studies suggest that low molecular weight heparin (LMWH) has superior efficacy, but advantages may be offset by higher expense. Since LMWH (enoxaparin sodium) became available, standard practice at our institution has been to treat all inpatients with myelopathy with LMWH. To examine the impact of this practice, all inpatients diagnosed with myelopathy and treated with LMWH were sequentially matched by diagnosis and compared in a retrospective review with inpatients treated with LDUH. In each group, 11 patients had traumatic injury, four had transverse myelitis, four had neoplasms and five had spinal stenosis. Characteristics of the LMWH/LDUH groups were: mean age--48.5/50.4; spinal level--cervical 13/7, thoracic 9/12, lumbar 2/5; American Spinal Injury Association impairment scale-A, 8/9; B, 2/2; C, 8/5; D, 6/8. There were five DVTs and two PEs in five patients taking LDUH; there were no cases of DVT or of PE in the LMWH group (p = 0.04, two-tailed chi-square test). Isolated DVTs occurred in two patients with traumatic injuries and in one patient with transverse myelitis; PE + DVT occurred in one patient with a primary and one patient with a metastatic tumor. All developed within 3.5 months of the onset of spinal dysfunction. One patient with a traumatic injury on ibuprofen and dexamethasone had a gastrointestinal hemorrhage while receiving LMWH. The cost of administration of LMWH was $24,499 compared with $5,700 for LDUH. The LDUH group spent a total of 57 days in an acute care facility, costing $57,000.00 and patients treated with LMWH spent nine days, costing $9,000.00. We conclude that treatment with LMWH was associated with a significant decrease in incidence of DVT/PE and an overall decline in health care costs of approximately $30,000 or approximately $1,250 per patient. PMID- 9360221 TI - Diazepam usage in veterans with spinal cord injury. AB - Diazepam is widely prescribed for persons with spinal cord injury (SCI) to treat muscular spasticity. To assess the current usage of diazepam in those persons with SCI being followed by the Department of Veterans Affairs Medical Centers (DVAMCs), a survey was mailed to all 23 DVAMCs that have specialized SCI Services. We discovered that no policy regarding the prescription of benzodiazepines existed at 65 percent of the SCI Services. At 70 percent of the SCI Services, diazepam or another benzodiazepine was routinely prescribed. One third of patients were estimated to have taken diazepam for greater than 10 years and an additional 37 percent for six to 10 years. Despite the potential for addiction, only 10 of the 23 SCI Services reported having a program to encourage discontinuation of diazepam use; a 20 percent success rate was reported in withdrawing this medication. A need for greater understanding with regard to the prescription of diazepam exists and strategies for its withdrawal should be considered. Appropriate guidelines for its use in patients with SCI and spasticity should be developed. PMID- 9360222 TI - Bladder management in patients with pediatric onset neurogenic bladders. AB - Our objective was to determine which clean intermittent catheterization (CIC) methods and supplies were used by patients with pediatric onset neurogenic bladders and to relate methodology and materials to reported urinary tract infections. Data were collected via questionnaires distributed by mail and at clinic visits at our university tertiary care outpatient pediatric rehabilitation clinic. Questionnaires were given to 165 patients. Fifty-nine percent were returned (68 patients with myelomeningocele, 27 with pediatric onset spinal cord injury (SCI) and two with other diagnoses). Mean age was 12 years (range 1-27). Fifty-four percent of patients participated in their own CIC. Only two percent used sterile catheterization technique, whereas 98 percent used CIC. A sterile catheter was employed with clean technique by 22 percent. Catheters were reused by 76 percent. Subjects used a wide ranging number of catheters per month, with a median of 5.3. There was no correlation between the number of urinary tract infections (UTIs) per year and the type of catheter used or the use of prophylactic antibiotics. Compared with patients with myelomeningocele, subjects with SCI were significantly more likely to use sterile catheters (p = 0.04), > 10 catheters per month (p = 0.01) and gloves (p < 0.001). Subjects who used gloves or more catheters were more likely to experience UTI. These data suggest that clean reused supplies are not related to an increased likelihood of UTI and should be considered a way to lower costs in these populations. PMID- 9360223 TI - Colonic transit time after spinal cord injury. AB - Colonic transit time (CTT) was measured with abdominal radiographs using Chaussade's technique in 30 spinal cord injured patients (ASIA A and B) following ingestion of 20 radiomarkers per day for three days. A significant increase in total CTT (p = 0.0001) and segmental CTT of the right colon (p = 0.0004) and of the left colon (p = 0.0001) was shown. While using on the average only 2.3 films of the abdomen per patient, we obtained results comparable with other radiologic techniques which use radiomarkers to measure CTT. The clinical relevance of these results is not clear and their correlation with intestinal symptoms remains to be investigated. PMID- 9360224 TI - Tetraparesis following dental extraction: case report and discussion of preventive measures for cervical spinal hyperextension injury. AB - This concerns a patient with compression myelopathy following passive hyperextension of the cervical spine during a dental procedure. Although he had been asymptomatic prior to the procedure, subsequent cervical spinal imaging revealed advanced spondylosis and spinal stenosis. Spinal stenosis is often asymptomatic for a long time. However, when radiculomyelopathy occurs after minor trauma to the head or neck, the patient is often found to have spinal stenosis. Specifically, hyperextension of a cervical spine with spondylotic changes can lead to compression myelopathy. Acquired spinal stenosis correlates positively with aging. As the size of the elderly population continues to increase the prevalence of cervical spondylotic radiculo-myelopathy will likely increase as well. Since appropriate precautions against potential neurologic damage can be undertaken, we suggest radiographic screening for pre-existing spinal stenosis prior to a procedure requiring hyperextension of the neck. Preventive measures for individuals with asymptomatic spondylotic changes and education of all health care professionals to avoid abrupt or prolonged hyperextension of the cervical spine is emphasized. PMID- 9360225 TI - Defining apoptosis: players and systems. AB - OBJECTIVE: To summarize the basic principles and concepts of apoptosis and some of the information to date regarding the nature of the regulation of apoptosis at the molecular level. METHODS: In the past few years, research in cell and molecular biology has led to a much better understanding of the underlying mechanisms that regulate apoptosis. RESULTS: Positive and negative regulatory elements that function in specific cell types to activate apoptosis have been identified. This activation involves signaling pathways that activate distinct proteolytic cascades that lead to the execution of cell death. CONCLUSION: Homeostasis involves a delicate balance between the processes of proliferation, differentiation, and death by apoptosis. The current challenge is to understand how specific stimuli regulate the execution of programmed cell death in basic reproductive cells and how these interactions are integrated into the overall physiology and pathophysiology of reproduction during life. PMID- 9360226 TI - Effect of indomethacin and N omega-nitro-L-arginine methyl ester on the pressure/flow relation in isolated perfused hindlimbs from pregnant and nonpregnant rats. AB - OBJECTIVE: To compare the pressure/flow relationship and to assess the roles of prostaglandins and nitric oxide in flow-induced vasodilation in the nonpregnant and late-pregnant rat hindlimb vasculature. METHODS: Pressure/flow and conductance/flow relationships were determined in isolated, Krebs buffer perfused, norepinephrine (0.5 mumol/L) preconstricted hindlimbs from nonpregnant and late-pregnant Wistar-Kyoto rats before and after inhibition of cyclo oxygenase with indomethacin (20 mumol/L), or nitric oxide synthase with N omega nitro-L-arginine methyl ester (300 mumol/L). RESULTS: There were no significant differences in baseline perfusion pressure between nonpregnant and pregnant rat hindlimbs perfused at 2 mL/min (20.6 +/- 0.8 and 19.7 +/- 1.1 mmHg, respectively) and norepinephrine increased perfusion pressure about twofold (40.8 +/- 2.0 and 34.8 +/- 1.8 mmHg, respectively). After constriction, perfusion pressure increased linearly as flow was increased in a stepwise manner to a maximum of 4 mL/min. The slope of the pressure/flow regression line for the pregnant rat hindlimbs (6.00) was significantly lower (P < or = .001) than that for the nonpregnant rat hindlimbs (8.44). Vascular conductance also increased as flow was increased, and was significantly greater at all flow rates in the pregnant compared to the nonpregnant rat hindlimbs. Indomethacin slightly decreased the constrictor response to norepinephrine and increased the pressure/flow regression line slope in nonpregnant, but not in pregnant rat hindlimbs. N omega-nitro-L arginine methyl ester abolished flow-mediated vasodilation in nonpregnant and pregnant rat hindlimbs, and there was no longer any significant difference between the pressure/flow regression line slopes. CONCLUSION: These results suggest that flow-induced vasodilation, mediated by endothelium-derived nitric oxide, is enhanced during pregnancy allowing the maternal vasculature to accommodate increased blood flow without increased blood pressure. PMID- 9360227 TI - Tissue DNA synthesis in the preterm ovine fetus following 8 hours of sustained hypoxemia. AB - OBJECTIVE: Protein synthesis is significantly decreased in the near-term ovine fetus in response to induced hypoxemia of several hours' duration. We therefore sought to determine the extent to which DNA synthesis rates as an index of tissue mitotic activity are also affected by similarly induced compromises in fetal oxygenation. METHODS: Fetal sheep were studied at 0.75 of gestation during a normoxic control period and an 8-hour experimental period of either sustained hypoxemia induced by lowering maternal inspired oxygen concentration of 11-8% (hypoxia group, n = 7) or continued exposure to room air (control group, n = 5). To estimate DNA synthesis rate, [3H]-thymidine (1 mCi/kg) was injected intravenously into each fetus at the beginning of the experimental period. RESULTS: Sustained hypoxemia with a reduction in fetal arterial O2 content from (mean +/- standard error of the mean) 4.3 +/- 0.1 to 1.5 +/- 0.1 mmol/L by the end of study resulted in a variable degree of fetal acidemia, 7.26 +/- 0.03 (range from 7.41 to 7.10), which was entirely metabolic in nature. CONCLUSION: The DNA synthesis rates of most tissues were not significantly changed by the 8 hours of sustained hypoxemia, suggesting that restrictions in protein synthesis in response to fetal hypoxia are initially due to a differential effect on nonmitotic synthetic processes at this stage of development. However, selective decreases in the DNA synthesis rates of the hippocampus (approximately 50%, P < .01), adrenals (approximately 48%, P < .05), and left and right myocardial ventricles (approximately 42% and 27%, respectively, P = .08) were evident which may reflect altered mitotic activity in response to tissue related changes in energy expenditure. PMID- 9360228 TI - Placental villous glucose metabolism and hormone release respond to varying oxygen tensions. AB - OBJECTIVE: The effects of varying oxygen tensions on tissue metabolic behavior are not well understood, yet many intracellular pathways are influenced by them. In the placenta, optimal in vivo oxygen tension at the villous level is unknown. The purpose of this study was to determine effects of varying oxygen tensions on glucose metabolism and hormone release from perifused placental villous explants. METHODS: Placentas from term normal pregnancies (n = 8) were individually minced into villous fragments, placed into three parallel chambers for each placenta, and continuously perifused for 6 hours with nonrecirculating medium aerated with either 0%, 20%, or 95% oxygen yielding mean oxygen tensions of 76 mmHg, 167 mmHg, and 543 mmHg respectively. Outflow medium was removed at regular intervals and compared to the inflow medium to determine oxygen and glucose consumption as well as lactate, lactate dehydrogenase, hCG, estradiol, and progesterone release. RESULTS: Oxygen consumption was directly proportional to oxygen tension. Glucose consumption was lowest at low oxygen tension, while both lactate and LDH release were lowest at high oxygen tension. Both hCG and progesterone release rates were lowest at high oxygen tensions. Estradiol release demonstrated a trend similar to that of the other hormones although there was no statistically significant difference among the three different levels of oxygen tension. CONCLUSION: Varying oxygen tensions affect placental villous glucose metabolism and hormone release. Under lower oxygen tensions, glucose is metabolized through glycolysis rather than through oxidative phosphorylation and is associated with higher lactate release. Exposure to higher oxygen tensions results in reduced hCG and progesterone release. Higher oxygen tensions may be associated with tissue toxicity. PMID- 9360229 TI - Expression of interleukin-10 in human gestational tissues. AB - OBJECTIVE: To determine production of interleukin-10 (IL-10) by interleukin-1 beta (IL-1 beta) in cultured decidual, chorion, and amnion cells and whether IL 10 is produced in gestational tissues under the setting of infection-associated preterm labor. METHODS: Decidual, chorion, and amnion cells were isolated from term placentas and grown in primary culture. The cells were incubated with various concentrations of IL-1 beta and then culture supernatants were assayed for IL-10 by enzyme-linked immunosorbent assay. In subsequent studies, gestational membranes were isolated from a normal-term pregnancy and a preterm pregnancy complicated by chorioamnionitis. Tissues were evaluated for IL-10 expression by immunohistology and in situ hybridization. Human gestational tissues were collected from 38 women experiencing: 1) term cesarean delivery without labor; 2) normal-term vaginal delivery; 3) preterm cesarean delivery without labor; 4) preterm vaginal delivery without chorioamnionitis; and 5) preterm vaginal delivery with concomitant chorioamnionitis. Amnion, chorion, and decidua were isolated, total RNA from each tissue was extracted, and the presence of IL-10 mRNA was determined by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Decidual cells in culture produced IL-10 in response to IL-1 beta, but chorion and amnion cells produced no IL-10 protein. In vivo protein expression by immunohistology showed that most protein was detected within decidua while cells within amnion and chorion rarely had detectable IL-10 protein. In vivo RT-PCR samples demonstrated the strongest IL-10 mRNA signal from decidua samples, although IL-10 mRNA was also noted in chorion and amnion of placentas obtained after preterm labor. CONCLUSION: Maternal decidual cells can potentially produce IL-10, but fetal membranes (amnion and chorion) appear to have limited capabilities to produce IL-10. The relative inability of fetal tissues to produce IL-10 may play an important role in the pathophysiology of infection-associated preterm labor. PMID- 9360230 TI - Red cell volume determination using a stable isotope of chromium. AB - OBJECTIVE: To validate and improve a method of red cell volume determination by use of a stable isotope of chromium. METHODS: Twelve subjects were sequentially injected with red blood cells labeled with a stable isotope of chromium (53Cr) and red blood cells labeled with radioisotopic chromium (51Cr). Measurement of 53Cr dilution was by gas chromatography/mass spectrometry. Measurement of 51Cr dilution was by gamma counter. RESULTS: Comparison of the two methods led to results that differed on average by 34.5 +/- 45.0 mL (1.8 +/- 2.2%), 0.3 to 3.2%, 95% confidence interval. CONCLUSION: Measurement of red cell volume by use of a stable isotope of chromium is accurate, with potential applications including measurement in pregnant women and children or other groups in whom exposure to radioisotopes is undesirable. PMID- 9360231 TI - The effect of recombinant growth hormone on the strength of ileal anastomoses in a rat model. AB - OBJECTIVE: In gynecologic surgery, the ileum is the primary site of bowel injury. Recombinant growth hormone (rGH) has been shown to improve the strength of colonic anastomoses in experimental models. The purpose of this study is to evaluate the effect of rGH on small bowel anastomoses, specifically in the ileum. METHODS: Twenty large female rats underwent segmental ileal resections and end-to end ileoileostomies. The rats were randomized to be treated for 7 postoperative days with either rGH (2.0 mg/kg/day) or placebo starting on the day of surgery. On the seventh postoperative day, a segment of ileum surrounding the anastomosis was resected. The anastomoses were tested for breaking strength on a tensiometer and for tissue concentrations of hydroxyproline. RESULTS: The ileal anastomotic breaking strength in the rGH group was 163.5 +/- 6.0 g (mean +/- standard error). In the placebo group, the breaking strength of ileal anastomoses was 125.0 +/- 3.0 g (P < .001). No significant difference was demonstrated with respect to the hydroxyproline concentration between the rGH group (15.2 +/- 2.0 micrograms/mg) and the placebo group (14.6 +/- 1.0 micrograms/mg). CONCLUSION: In an animal model, a 31% increase in ileal anastomotic breaking strength was induced by rGH administration. With further research this may translate into decreases in the surgical complications that occur in ileal anastomoses. Furthermore, these serve as preliminary data to a study that evaluates the effect of rGH on ileal anastomoses in radiation-injured bowel. PMID- 9360232 TI - Numerical chromosomal aberrations in borderline, benign, and malignant epithelial tumors of the ovary: correlation with p53 protein overexpression and Ki-67. AB - OBJECTIVE: Ovarian tumors of low malignant potential (borderline tumors) have a 5 year survival rate of 69-98%, illustrating that while the prognosis is better than in the typical epithelial carcinoma, a significant number of women still succumb to this disease. The aim of our study was to elucidate the role of numerical chromosomal aberrations in borderline tumors of the ovary in comparison with benign and malignant epithelial tumors in an effort to develop parameters to differentiate prospectively borderline lesions from benign and invasive tumors. METHODS: Cytologic imprints of surgical specimens of 46 ovarian tumors of low malignant potential, 17 invasive epithelial carcinomas of the ovary, and 18 benign epithelial tumors of the ovary were examined for numerical chromosomal aberrations (trisomy 7, trisomy 12, and trisomy 17) by fluorescence in situ hybridization (FISH). RESULTS: In benign tumors no evidence of trisomy 7 and 17 was present. Trisomy 12 was detected in six cases (33.3%). We did not find p53 protein overexpression in any case. Ki-67 stained positive in three cases (16.7%). In borderline tumors trisomy 12 was detected in 33 patients (71.7%). Numerical aberrations of chromosome 17 were absent in all cases. Fourteen patients (30.4%) showed trisomy 7. No immunohistochemical staining reaction for p53 protein was found. Staining of the proliferation marker Ki-67 was observed in two cases (4.3%). In malignant epithelial tumors of the ovary, trisomy 7, trisomy 12, and trisomy 17 were detected in 14 (82.3%), 11 (64.7%), and 5 (29.4%) cases, respectively. Four tumors (23.5%) showed immunohistochemically detected p53 protein overexpression. Thirteen tumors (76.5%) stained for Ki-67. CONCLUSION: Our results indicate that trisomy 7 argues against benign disease. Trisomy 17 was specific for invasive disease, while trisomy 12 is common in borderline tumors of the ovary. PMID- 9360233 TI - Predicted and actual fetal weight throughout the last trimester. AB - The aim of our study was to obtain, in normal pregnancies, references values of predicted and actual fetal weight for both male and female fetuses and for fetuses born to nulliparous and multiparous women between weeks 28 and 41 of gestation. Predicted fetal weight curves represented calculations of weight in the third trimester based on weight data obtained during the second trimester. These curves were obtained from 134 ultrasonograms obtained between weeks 20 and 27. Actual fetal weight curves represented the values calculated from third trimester measurements and were based on 374 ultrasonograms obtained between weeks 28 and 41. For predicted fetal weight minor differences were found between male and female fetuses and between fetuses born to nulliparous and multiparous women. For actual weights, differences increased progressively for gender and parity during the last trimester. Predicted weights progressed at a steeper rate, and this effect was stressed in cases of female fetuses and fetuses born to nulliparous women. If predicted weights reflect normal growth, differences between fetal gender or maternal parity might be due to environmental influences. Therefore, it might not be justified to construct separate weight charts differentiated by sex or parity. PMID- 9360234 TI - Sonographic features of mammary oil cysts. AB - Mammographic lesions that are pathognomonic for oil cysts require no further evaluation. Oil cysts, however, may first be discovered by ultrasonography. Between 1988 and 1995, we performed sonography of 26 oil cysts in 15 patients. Sonography was used to evaluate a palpable finding when an oil cyst was not initially perceived on the mammogram (47%) or as an initial evaluation of a palpable lump (33%); in addition, oil cysts were identified incidentally in 20% of cases. Retrospective review showed that the sonographic appearance of oil cysts is highly variable; only 8% mimic simple apocrine cysts. Twelve percent mimic an intracystic mass. Most have smooth walls (88%), are hypoechoic (65%), and have neither enhancement or shadowing (50%). The sonographic appearance of oil cysts can be suggestive of a pathologic lesion such as an intracystic carcinoma. Unnecessary biopsy can be avoided using directed mammography. PMID- 9360235 TI - Human dural thickness measured by ultrasonographic method: reflection of intracranial pressure. AB - We measured changes in dural thickness to estimate intracranial pressure. The dural thickness on magnetic resonance imaging with contrast enhancement was compared in a hydrocephalic patient before and after shunt operation. Dural thickness also was measured directly using a micrometer at craniotomy for aneurysmal clipping in 11 patients. A small ultrasound probe (5 MHz) was held against the temporal scalp of 10 volunteers to extract convoluted interference echoes from the dura mater using a computer--based system for fast Fourier transform-Cepstrum analysis and maximum entropy analysis. The degree of intracranial pressure in the supine position was varied in the volunteers with transient neck compression. The enhanced dural thickness of the patient with hydrocephalus, barely visualized before shunt operation, increased after surgery. Dural thickness measurements obtained ultrasonographically in the supine position were similar to direct measurements of thickness. Changes in dural thickness on ultrasonography reflect changes in intracranial pressure. PMID- 9360236 TI - Clinical significance of isolated enlargement of the cisterna magna (> 10 mm) on prenatal sonography. AB - Enlargement of the cisterna magna has been reported to be associated with aneuploidy. In prior studies of cisterna magna enlargement, however, those fetuses with abnormal chromosomes have had other sonographic abnormalities in addition to a large cisterna magna. Our goal was to assess the clinical significance of the isolated finding of a cisterna magna measuring more than 10 mm in anteroposterior dimension on a prenatal sonogram. We retrieved all prenatal sonograms performed at our institution between 1989 and 1996 in which an enlarged cisterna magna was the only sonographic abnormality. Cases were included in our study if the cisterna magna measured more than 10 mm in the appropriate plane and the fetal survey was otherwise normal, including normal cerebellar size and morphology. Pregnancy outcome and postnatal follow-up were obtained in each case. Fifteen cases comprised our study population. In all 15 fetuses, the enlarged cisterna magna was first seen in the third trimester (gestational age range, 26 to 37 weeks). The cisterna magna ranged from 11 to 19 mm in size (mean, 12.9 mm). All 15 pregnancies resulted in phenotypically normal liveborn infants. All the mother and infants had short hospital stays (1 to 4 days), and the infants were normal at discharge. Longer follow-up was available in eight cases (range, 2 to 69 months), and all eight of these infants were normal. Our results suggest that isolated enlargement of the cisterna magna to more than 10 mm is associated with normal pregnancy and neonatal outcome. PMID- 9360237 TI - Effects of oophorectomy and hormone replacement therapy on ophthalmic artery blood flow velocity waveforms. AB - Our objective was to compare ophthalmic artery flow velocity waveforms in unilateral oophorectomized patients not on hormone replacement therapy with findings in bilateral oophorectomized patients on hormone replacement therapy. Ten patients who underwent hysterectomy and unilateral oophorectomy and 10 women treated by hysterectomy and bilateral oophorectomy were studied using color and pulsed Doppler ultrasonography 1 day before and on days 7 and 28 after surgery. Serum estradiol levels were measured serially. Bilateral oophorectomy patients were given hormone replacement therapy (conjugated estrogen, 0.625 mg/day, and medroxyprogesterone acetate, 2.5 mg/day) orally starting on day 8 after surgery. The pulsatility index values of the ophthalmic artery in unilateral oophorectomy patients were 1.93 +/- 0.41, 2.10 +/- 0.26, and 1.68 +/- 0.27 for 1 day before and on days 7 and 28 after surgery, respectively. The pulsatility index values of the ophthalmic artery in bilateral oophorectomy patients were 1.99 +/- 0.39, 2.17 +/- 0.47, and 1.75 +/- 0.32 for 1 day before and on days 7 and 28 after surgery, respectively. No significant differences were found between pulsatility index values in the unilateral and bilateral oophorectomy patients in each time period. The pulsatility index values on day 28 decreased significantly compared with the findings on day 7 in both groups (P < 0.05). The serum estradiol levels were significantly reduced from 1 day before to day 7 day after surgery and were significantly elevated by day 28 after surgery (P < 0.05) in both groups of patients. No significant differences were found between the serum estradiol levels in the unilateral and bilateral oophorectomy patients in each time period. Vascular tone in the ophthalmic artery seems to change according to serum estradiol levels, a finding that may help explain some of the beneficial effects of hormone replacement therapy for bilateral oophorectomized patients. PMID- 9360238 TI - Isolated splenic metastases. AB - We analyzed the primary tumors, sonographic findings, clinical manifestations, and prognosis in five cases of isolated splenic metastases to determine in what situations these rare metastases should be suspected. The metastases were detected by ultrasonography in all five patients, and the primary tumors were colonic cancer in four patients and renal cancer in one patient. Splenectomy was performed and the postoperative course was uneventful in all patients. We conclude that preoperative and follow-up examinations must be performed with special attention given to the spleen in colonic or renal cancer patients. PMID- 9360239 TI - Penile metastasis from prostate cancer: diagnosis with sonography. PMID- 9360240 TI - Prenatal diagnosis of de Lange syndrome. PMID- 9360241 TI - Unusual presentation of amniotic band syndrome. PMID- 9360242 TI - Intrahepatic microlithiasis: another gastrointestinal complication of cystic fibrosis. PMID- 9360243 TI - Cyst of the velum interpositum: antenatal ultrasonographic features and differential diagnosis. PMID- 9360244 TI - Proliferative myositis: rare pseudotumorous lesion. PMID- 9360245 TI - Fever of unknown origin in the HIV-infected patient: new scenario for an old problem. AB - Many conditions may present as fever of unknown origin in the HIV-infected patient, and their relative frequency is influenced by multiple factors. The history and physical examination may provide some useful clues for the diagnosis. Haematological, biochemical, and conventional radiological tests are rarely diagnostic; even serological and/or microbiological tests have some limitations in these patients. The geographical setting and the local prevalence of diseases are of the utmost importance. Infections that have a world-wide distribution, such as tuberculosis, should be intensively searched for, particularly in areas of high prevalence. The measurement of the CD4+ cell count is essential, as there is a strong association between this count and certain opportunistic diseases that may manifest as fever of unknown origin. Imaging procedures, such as CT and radionuclide scans, are useful for the location of inflammatory and neoplastic lesions. Liver and bone marrow biopsies are helpful in certain subsets of patients and the efficacy of empirical treatments has been clearly documented in certain infections. Some HIV-infected patients with fever of unknown origin remain undiagnosed after a thorough investigation; these individuals should be managed conservatively. Finally, symptomatic treatment is the best option for terminally ill patients in whom benefit from a detailed investigation of the cause of fever is not expected. PMID- 9360246 TI - Influence of age on rates of new AIDS-defining diseases and survival in 6546 AIDS patients. AB - It has consistently been reported that older AIDS patients have a shortened survival compared with younger patients. The aim of the present study was to investigate whether this difference in survival is caused by differences in the pattern of the complicating diseases. Information on patient follow-up after the AIDS diagnosis was obtained by retrospective case note review. The 6,546 patients were followed from the time of AIDS diagnosis as part of the multicentre AIDS in Europe study, which examined AIDS cases diagnosed at 52 centres in 17 European countries between 1979 and 1989. Occurrence of AIDS-defining events and demographic variables were recorded for all patients, and CD4 lymphocyte count at the time of AIDS diagnosis for approximately half the patients. After adjusting for imbalances in other variables, persons > or = 50 years of age had a significantly higher risk of contracting AIDS wasting syndrome, AIDS dementia complex and oesophageal candidiasis after the initial AIDS diagnosis, compared with age group 30-39 years [relative risk (RR) 95% confidence interval (CI)], 3.23 (2.70-3.75 CI); 2.48 (2.16-2.80 CI); 1.55 (1.26-1.83 CI), respectively]. Shortened survival after the time of AIDS diagnosis was associated with older age. After adjusting for pattern of complicating diseases, the age effect remained unchanged. Older age predisposes to AIDS-related wasting syndrome, AIDS dementia complex and oesophageal candidiasis. Independent of these differences, older age is significantly associated with shortened survival, suggesting that factors such as severity of complicating diseases or the capability of handling serious infections, rather than disease pattern, are responsible for the shortened survival. PMID- 9360247 TI - Hepatitis C virus seroconversion rate in a hyperendemic area of HCV in Japan: a prospective study. AB - We have studied the prevalence, seroconversion rate of anti-hepatitis C virus (HCV), and the transmission of HCV in a cohort of individuals living in a hyperendemic area of HCV in Japan. We investigated 509 subjects, of which 375 could be studied again after 5 years. A remarkable high prevalence of anti-HCV (23.4-24.0%) was observed. Of 287 subjects negative at the first examination in 1990, 4 became positive until the second in 1995 (seroconversion rate: 0.28% per year). Furthermore, we investigated the route of transmission in HCV seroconverted subjects through a detailed interview. All of the HCV seroconverted subjects had past histories of medical treatment. Seroconversion rates of HCV in a hyperendemic area of HCV, were extremely high. Medical treatment was considered to be a causative route of HCV transmission. PMID- 9360248 TI - Prevalence of serum antibodies to hantaviruses in northern Sweden as measured by recombinant nucleocapsid proteins. AB - An enzyme-linked immunosorbent assay (ELISA) based on recombinant nucleocapsid protein (rN delta) (aa 1-117) of Hantaan, Seoul, Dobrava, Sin Nombre and Puumala hantaviruses was used to determine the prevalence of antibodies among randomized and stratified individuals from northern Sweden. In total, 137/1533 individuals (8.9%) had specific serum IgG antibodies to Puumala virus, the only hantavirus known to occur in the region. The prevalence of antibodies to Puumala virus (8.9%) was determined to be higher than previously reported (5.4%) in the same serum material, by use of immunofluorescence assay. As expected, sera reactive to Puumala virus rN delta did frequently cross-react with Sin Nombre virus protein. Unexpectedly, 21/1533 (1.4%) individuals recognized the Sin Nombre virus rN delta exclusively. Another 8 subjects showed reactivity in the ELISA to Hantaan, Seoul, or Dobrava virus-derived rN delta but not Puumala virus or Sin Nombre virus rN delta. The present demonstration in some individuals of antibodies specifically recognizing the Sin Nombre, Dobrava, Hantaan and Seoul virus protein justifies an awareness of the possibility that hantaviruses antigenically different from Puumala virus might occur in the region. PMID- 9360249 TI - HIV infection and malnutrition change the clinical and radiological features of pulmonary tuberculosis. AB - Patients with HIV infection have atypical clinical features of pulmonary tuberculosis; however, our knowledge on how malnutrition affects the clinical presentation is limited. We studied the influence of malnutrition and HIV infection on the clinical and radiological features of pulmonary tuberculosis (TB). We studied 239 consecutive acid fast bacillus-positive adult patients. Patients were investigated by clinical, radiological, anthropometric and laboratory methods. 78% of the patients were malnourished (BMI < 18.5) and 43% were severely malnourished (BMI < 16). 20% were HIV-positive. HIV-positive TB had significantly more oral candidiasis (OR = 3.72), diarrhoea (OR = 2.71), generalized lymphadenopathy (OR = 2.63), skin disorders (OR = 2.27), neuropsychiatric illness (OR = 2.44), hilar lymphadenopathy (OR = 2.07), but less cavitation (OR = 0.64) and upper lung lobe involvement (OR = 0.70). HIV-negative and severe malnourished patients presented more often with dyspnoea (OR = 1.44), diarrhoea (OR = 1.64), night sweat (OR = 1.83), and less with haemoptysis (OR = 0.58) and cavitation (OR = 0.64). The size of Mantoux was associated with HIV infection and malnutrition. In a logistic regression analysis both HIV status and malnutrition were associated with atypical presentation of pulmonary tuberculosis. Malnutrition and HIV infection both contribute for atypical presentation of pulmonary tuberculosis. The risk of such atypical presentation is particularly high among the severely malnourished HIV-infected patients. PMID- 9360250 TI - High incidence of Chlamydia pneumoniae in sclerotic heart valves of patients undergoing aortic valve replacement. AB - Chlamydia pneumoniae has previously been demonstrated in the atherosclerotic lesions of various arteries, including the coronary arteries, and has been proposed to play a role in the pathogenesis of atherosclerosis. A prospective study of the incidence of C. pneumoniae in the sclerotic valves of patients undergoing aortic valve replacement because of aortic stenosis and in the aortic valves of cases dying of non-cardiac reasons and undergoing forensic autopsy was undertaken. The results were correlated to serological markers of past (IgG) or persistent (IgA) C. pneumoniae infection. C. pneumoniae, as determined by the polymerase chain reaction (PCR), was detected in the aortic valve in 19/39 (49%) patients and in 1/11 (9%) autopsy controls (p = 0.018) and confirmed by electron microscopy in one patient. There was no significant difference in the incidence rate of IgG or IgA antibody positivity between PCR-positive and PCR-negative cardiac patients. These results extend the hypothesis of a pathogenic role of C. pneumoniae in atherosclerosis to include also aortic valve sclerosis. PMID- 9360251 TI - Neutrophil chemotactic activity in bronchoalveolar lavage fluid of patients with AIDS-associated Pneumocystis carinii pneumonia. AB - Pneumocystis carinii pneumonia (PCP) is accompanied by an acute inflammatory infiltration of the lung parenchyma. The cellular infiltrate is characterized by inflammatory cells including neutrophils, lymphocytes and macrophages. Furthermore, neutrophilia in bronchoalveolar lavage (BAL) fluid has been shown to confer a poor prognosis in PCP. We therefore investigated the potential of BAL fluid from 17 patients with PCP to induce neutrophil chemotaxis. BAL fluid from patients induced considerable neutrophil chemotactic activity compared to normal controls. Elevated levels of IL-8 were detected in patient samples as compared to controls. A specific anti-IL-8 antibody significantly reduced chemotactic activity of patient samples by more than 50%. In conclusion, IL-8 appears to be a significant participant of neutrophil chemotaxis in AIDS-associated PCP, and may participate in the recruitment of neutrophils to the lung during PCP. PMID- 9360252 TI - Eradication of penicillin-resistant pneumococci in the nasopharynx with antibiotic combinations including rifampicin: experiences from the South Swedish Pneumococcal Intervention Project. AB - 39 children with prolonged nasopharyngeal carriage (48-328 days) of intermediately to highly penicillin-resistant pneumococci (PRP) were treated for 7 days with rifampicin in combination with amoxicillin (n = 18) erythromycin (n = 17) or clindamycin (n = 4), according to resistance pattern. In all children, except for 1 carrying a rifampicin-resistant strain, control cultures from the nasopharynx 1-2 weeks after the last antibiotic dosage, yielded no growth of PRP. In 2 brothers, PRP with the same serogroup and resistance pattern were found in nasopharynx 10 weeks after the antibiotic treatment. These preliminary findings indicate that antibiotic regimens including rifampicin are effective in eradicating nasopharyngeal carriage, but reappearance of the same strain may occur after several weeks. Such treatments should be given with caution due to the risk of selecting rifampicin-resistant strains. Further controlled studies are needed to determine the optimal combination of antibiotics and appropriate duration of therapy. PMID- 9360253 TI - Antibiotic and prednisolone therapy of erysipelas: a randomized, double blind, placebo-controlled study. AB - 112 patients admitted to hospital with a diagnosis of erysipelas, were randomized to 8 days treatment with prednisolone or placebo in addition to antibiotics. 108 patients received the study drugs and were evaluated for time to cure, which was the primary end-point. The median healing time was significantly shorter in the prednisolone group, 5 days, vs 6 days in the placebo group (p < 0.01). The 90th percentile healing time was 10.0 days in the prednisolone group vs 14.6 days in the control group. The prednisolone-treated patients had a median length of hospital stay (secondary end-point) of 5 days vs 6 for the placebo-treated (p < 0.01). The median treatment time with intravenous antibiotics (secondary end point) was 4 days in the placebo group, which was 1 day longer than in the prednisolone group (p < 0.05). 13 patients, 7 of whom received placebo, relapsed during the observation period of 3 weeks. The frequency of side effects attributable to the study drug was not higher in the prednisolone group. PMID- 9360254 TI - Comparative effects of levofloxacin and ofloxacin on the normal oral and intestinal microflora. AB - The aim of the study was to study the ecological effects of levofloxacin, compared to that of ofloxacin, on the oral and intestinal human microflora. 10 healthy volunteers received levofloxacin (500 mg) and 10 subjects were given ofloxacin (400 mg) perorally, once daily for 7 days. Saliva and stool samples were obtained prior to drug administration, during administration (days 2, 4 and 7), and after withdrawal of the agents (days 9, 11, 14 and 21). The concentrations of levofloxacin and ofloxacin in the saliva and faecal samples, respectively, were assayed, and quantitative and qualitative microbiological analyses were performed. Oral administration of levofloxacin and ofloxacin led to low drug concentrations in the saliva, which corresponded with mild disturbances in the oral microflora. High drug levels were obtained in the intestinal tract, and both agents caused a selective reduction in the normal microflora, mainly directed towards aerobic Gram-negative bacteria. There was no significant difference between levofloxacin and ofloxacin, regarding ecological effects on the normal oral and intestinal microflora. From an ecological point of view, these agents acted favourably, since no major selection of resistant strains occurred in the normal microflora during administration. PMID- 9360255 TI - Recurrence of pneumonia in middle-aged and elderly adults after hospital-treated pneumonia: aetiology and predisposing conditions. AB - In order to investigate the predisposing conditions and aetiologic agents in patients with recurrent pneumonia, we prospectively studied 653 immunocompetent patients, 50-85 years of age, who had been treated in hospital for community acquired pneumonia. After an average patient follow-up period of 32 months, 11 variables were examined for association with the following end points: death, recurrence of pneumonia and recurrence of pneumococcal pneumonia. During the follow-up period there were 171 episodes of pneumonia in 115 of the 653 patients, and 52 deaths (all causes). Multivariate analysis showed that age, male sex, congestive heart failure and presence of other chronic diseases were significantly associated with higher mortality. Age and chronic pulmonary disease were associated with recurrence of pneumonia. The major aetiologic agents were Streptococcus pneumoniae (26%), Haemophilus influenzae (11%) and Moraxella catarrhalis (6%). We conclude that pneumonia recurrences are common in middle aged and elderly patients after treatment in hospital for community-acquired pneumonia. The recurrence risk is higher in elderly patients, and in those with chronic pulmonary diseases. Given the prominence of H. influenzae and M. catarrhalis found in the present study, these organisms should always be considered when choosing the initial antibiotic in patients with recurrent pneumonia. PMID- 9360256 TI - The influence of growth hormone on tumour necrosis factor and neutrophil leukocyte function in sepsis. AB - The aim of this study was to assess the influence of growth hormone (GH) in sepsis on the immune system represented by the circulating TNF-levels and the neutrophil leukocytes phagocytic capacity and respiratory burst, 22 piglets were randomized to 3 groups; pretreatment with GH (16 i.u.) before sepsis (n = 8), non treated septic controls (n = 8), and non-septic controls (n = 6). Sepsis was induced by a standardized infusion of live E. coli. TNF was measured by a cytotoxic bioassay, while neutrophil function tests were carried out by flowcytometric assays. In brief, phagocytosis was evaluated by the neutrophils' ability to ingest FITC-labelled (fluorescein isothiocyanate) E. coli and intracellular release of oxygen metabolites was detected by the oxidation of 2',7'-dichlorofluorescin (DCFH) to the fluorescent 2',7'-dichlorofluorescein (DCF). Our data show a suppression of phagocytosis in the GH-treated group before sepsis; however, when challenged with Gram-negative bacteria, the phagocytic capacity was similar to that of the non-treated animals. The serum levels of TNF in the non-treated septic control group were twice the levels of those in the GH treated group, 65.7 pg/ml (septic controls) vs 32.8 pg/ml (GH). Pretreatment with a single dose of GH few hours prior to sepsis does not seem to entail any further imbalance of the neutrophil function in sepsis. Lowering of the circulating TNF levels is a presumptive favourable effect of GH in sepsis. PMID- 9360257 TI - Immunoglobulin deficiencies and impaired immune response to polysaccharide antigens in adult patients with recurrent community-acquired pneumonia. AB - The frequency of humoral immunodeficiencies was analysed in 39 patients with a history of recurrent (> or = 3) episodes of community-acquired pneumonia. Total immunoglobulin levels and/or IgG subclass levels were low in 14 patients (36%), including eight patients with IgG or IgG2 deficiency. The specific antibody activity to pneumococcal capsular polysaccharides (serotypes 3, 6A, 19F, and 23F) and to phosphorylcholine was low in the IgG/IgG2-deficient patients compared to 36 healthy controls, and they also responded poorly to vaccination with a 23 valent pneumococcal capsular polysaccharide vaccine. The remaining 25 patients, with normal immunoglobulin and IgG subclass levels, had specific anti pneumococcal antibody levels comparable to the healthy controls, and all but 3 responded to vaccination. We conclude that immunoglobulin deficiencies and the inability to respond to polysaccharide antigens are common risk factors for recurrent pneumonia in adult patients. Immunoglobulin levels (including IgG subclasses) and antibody response to polysaccharide antigens should be investigated in these patients. PMID- 9360258 TI - High prescribers of antibiotics among general practitioners--relation to prescribing habits of other drugs and use of microbiological diagnostics. AB - General practitioners' (GPs') prescriptions of antibiotics have shown large variations and may not always be rational. We analysed GPs' prescriptions and use of microbiological diagnostics in Viborg County during a 6-month period in 1992 based on Danish Health Service data. In a logistic regression model we tried to identify potential predictors for a high prescriber of antibiotics, i.e. the GPs with the highest number of prescriptions per patient (upper quartile). Two categories were calculated for the predictor variables, dividing the distribution by the median value. The most liberal GP wrote 15 times as many prescriptions for antibiotics per patient as the most restrictive GP. A strong predictor for high prescribing of antibiotics was the number of prescriptions for other drugs per patient [odds ratio (OR) 12.3, 95% CI: 2.8-54.4] after adjustment for age and sex. High use of throat swabs was a strong negative predictor of high prescribing of antibiotics (OR 0.2, 95% CI: 0.1-0.8) while high use of cultures (OR 2.4, 95% CI: 0.8-6.9) and of urinary susceptibility tests (OR 3.1, 95% CI: 1.1-9.3) were positive predictors. The GP's general attitude to pharmacotherapy seems important for antimicrobial chemotherapy, and if use of antibiotics should be reduced, targeted strategies should be aimed at high prescribers. PMID- 9360259 TI - Waterborne outbreak of viral gastroenteritis. AB - A waterborne epidemic took place in a Finnish municipality in April 1994. Some 1500-3000 people, i.e. 25-50% of the population, had symptomatic acute gastroenteritis. Laboratory findings confirmed adenovirus, a Norwalk-like agent, small round viruses (SRV), and group A and C rotaviruses as causative agents, Norwalk virus being the main cause of the outbreak. The epidemic was most probably associated with contaminated drinking water. The groundwater well, situated in the embankment of a river, was contaminated by polluted river water during the spring flood. A back flow from the river to the well had occurred via a forgotten drainage pipe. PMID- 9360260 TI - Rothia dentocariosa: two new cases of pneumonia revealing lung cancer. AB - Pneumonia due to Rothia dentocariosa is extremely rare: only 1 case of pneumonia due to this pathogen has been reported in an immunocompromised patient with acute myelocytic leukemia. In this report, 2 new cases of Rothia dentocariosa pneumonia are described in 2 patients with lung cancer. This opportunistic pulmonary agent, belonging to the oro-pharyngeal flora, is also known to cause endocarditis in patients with underlying cardiac pathology. PMID- 9360261 TI - Cellulitis associated with an oral source of infection in breast cancer patients: report of two cases. AB - We present 2 patients with prior lumpectomy, axillary node dissection and radiation therapy for treatment of breast cancer, who subsequently developed arm and chest cellulitis associated with an oral infection (gingivitis with bacteremia in one patient, and dental abscess in another). Our findings suggest that hematogeneous seeding of the compromised extremity and/or breast from the oral cavity should be considered as a possible cause of cellulitis in breast cancer patients. PMID- 9360262 TI - Splenic abscess caused by Salmonella braenderup, treated with percutaneous drainage and antibiotics. AB - Splenic abscess is a rare condition and its optimal treatment is still debated. We report on a 17-year-old immunocompetent female patient, hospitalized with Salmonella braenderup gastroenteritis and splenic abscess, who was treated with ciprofloxacin, percutaneous catheter drainage and despite remaining drainage of 50 ml/24 h, the catheter was removed and the antibiotic treatment was stopped when the fluid was clear. Following removal a transient increase in the size of the splenic cavity was observed, but without any clinical symptoms or deterioration of laboratory parameters. At the 1-year follow-up, ultrasound examination of the spleen disclosed only a 8 mm scar. PMID- 9360263 TI - Fatal encephalitis caused by Mycoplasma pneumoniae in a 9-year-old girl. AB - A case of fatal encephalitis in a 9-year-old girl is described. Serology showed high titre antibodies against Mycoplasma pneumoniae. In addition M. pneumoniae was detected in cerebrospinal fluid by polymerase chain reaction. Direct invasion of the central nervous system as opposed to a secondary immunologic reaction to a M. pneumoniae infection of the respiratory tract in the pathogenesis of encephalitis is discussed. PMID- 9360264 TI - Mediastinal lymphadenitis associated with Chlamydia pneumoniae infection. AB - A young woman presented with mediastinal lymphadenitis and measles-like eruption. All clinical manifestations promptly responded to macrolide therapy. Serologically, current infection of Chlamydia pneumoniae was highly suspected. Evaluation of Chlamydia pneumoniae infection should be included in the diagnostic approach to mediastinal lymphadenitis. PMID- 9360265 TI - Laryngeal candidiasis in children. AB - Candidiasis of the larynx is rare and often related to immunocompromised hosts. We here report a case of laryngeal candidiasis in an immunocompetent infant. The diagnosis was obtained by direct fibre-optic laryngoscopy with specimens submitted for culture. He received anti-fungal medication and was quite well at 1 year follow up. The pertinent literature is also reviewed. PMID- 9360266 TI - Meningoencephalitis caused by Cryptococcus macerans. AB - A case of meningoencephalitis caused by Cryptococcus macerans is described. The infection caused a severe form of epilepsy. Antifungal therapy based on fluconazol was successful in halting the disease process. The patient remained, however, unable to resume his job and previous activities. PMID- 9360267 TI - Pitfalls in the diagnosis of airport malaria. Seven cases observed in the Paris area in 1994. AB - Clinical and biological pitfalls that lead to incorrect or delayed diagnoses of airport malaria are described based on 7 cases reported from the Paris region in the summer of 1994. We also report the outcome and the epidemiological features of these patients. PMID- 9360268 TI - Invasive Aspergillus sinusitis during bone marrow transplantation. AB - Aspergillus sinusitis is usually a lethal condition in bone marrow transplanted patients. We report the case of a patient known to have a sinus infection with Aspergillus flavus before treatment with allogenic bone marrow transplantation for a refractory acute myelogenous leukemia. Exacerbation of the sinusitis during the neutropenic period required a multidisciplinary approach. Cure was achieved after treatment with a combination of surgery (Caldwell-Luc procedure), long term ABCD (amphotericin B colloidal dispersion) therapy (7 months) and granulocyte transfusions during the period preceding engraftment. The use of granulocyte transfusion in this salvage setting is discussed. Aggressive multimodality management of aspergillus sinusitis in immunosuppressed patients may lead to a cure and might not preclude allogenic transplantation. PMID- 9360269 TI - Why is prevention so difficult and slow? AB - The abundance of perceived 'possibilities' for prevention contrasts sharply with the difficulties that face preventive programmes. We argue that this situation has emerged from an incomplete understanding of the process of prevention, involving a mixture of biological factors, human decision making and time perspectives. Based on examples, an analysis of the factors in the prevention process is presented. PMID- 9360270 TI - Health habits and risk behavior among youth in three communities with different public health approach. AB - BACKGROUND: There is a consensus today that comprehensive public health activities including many actors are needed for impact on health compromising behaviors. However, few studies are available to document long term effects regarding youth. We identified three rural, demographically comparable communities dominated by nuclear middle class families. One of these communities demonstrated comprehensive public health activities directed towards adolescents' needs and life-styles for a duration of at least 15 years, while the other two had an outspoken ideology of relying only on national health promotion. METHODS: Local health planners and pediatricians performed in-depth interviews with key people and checked relevant reports to trace the local public health history and to assess conventional and unconventional activities regarding health promotion for adolescents in the three communities. The outcome of at least 15 years of different policy regarding health promotion was studied in 1991 through self reports of 915 subjects, 13-16 years old, with a questionnaire distributed through schools with questions on health, health habits and health compromising behaviors. The study itself turned out to be an important intervention. The two "inactive" communities changed their policy and methods. For this reason a second survey was done in 1993 with 593 subjects 13-16 years in the "active" and in one of the "inactive" communities. RESULTS: The adolescents in the "active" community with a long duration of energetic and comprehensive public health activities consistently demonstrated better mental health, health habits and less risk behavior in contrast to the state in the two "inactive" communities. Two years of active work in the "inactive" communities marginally improved health there. CONCLUSION: This study suggests that consistent and comprehensive public health activities might have reduced risk taking behavior and improved health and health habits during mid-adolescence. PMID- 9360271 TI - Associations of health-related behaviors, school type and health status to physical activity patterns in 16 year old boys and girls. AB - Sedentary behavior often begins in childhood and is associated with the development of risk factors for many chronic diseases in adulthood. Physical activity is considered important in the prevention of unfavorable changes in the risk factors. We investigated whether health-related behaviors, school type and health status are associated to physical activity among adolescents. A questionnaire was sent to all Finnish 16-year-old twins in 1991-93. A total of 3,254 twins responded. The response rate was 88%. Physical activity was classified into five categories (very active, active, moderately active, hardly active, inactive) based on self-reported frequency and intensity of physical activity. The analysis considered all subjects as individuals. Smoking was strongly associated with physical activity among girls and boys. Those who smoked regularly were less active. The type of school was also associated with physical activity. In general, those who attended comprehensive school or high school were physically more active, while those in vocational schools, particularly boys, were less active. Girls in lower physical activity groups reported more psychosomatic symptoms. Associations of self-reported health-related behaviors, school type and health status to physical activity seem to be the same among boys and girls. However, as the more active students are in comprehensive school or high school and the less active in vocational school, and physical inactivity is related to smoking and use of alcohol, health education should be tailored by school type. PMID- 9360272 TI - Lifestyle as regards physical exercise, smoking and drinking, of adult insulin treated diabetic people compared with non-diabetic controls. AB - Chronic complications in diabetes are sometimes associated with living habits. To investigate whether diabetic people's habits of smoking, drinking alcohol and taking physical exercise differed from those of the general population, a questionnaire was sent to 561 insulin-treated diabetic people and to 1,125 controls, matched for age, sex and domicile. Diabetic people were current smokers as often as controls (21% vs 23%; ns), but they drank less alcohol and more of them were non-drinkers (22% vs 13%; p < 0.001). Diabetic people more often took physical exercise than did controls (40% vs 28%; p < 0.001). Diabetic women were more seldom smokers (18% vs 26%; p < 0.05), more often non-drinkers (26% vs 14%; p < 0.001) and exercised regularly more (44% vs 28%; p < 0.001) than female controls. Diabetic men were more similar to male controls in their habits. Young diabetic people drank less alcohol and were more often non-drinkers (22% vs 9%; p < 0.001) compared with their controls. Comparison within the diabetic group showed that men drank alcohol more frequently and in greater amounts, and that more women were non-drinkers (26% vs 18%; p < 0.05). People with chronic complications drank less frequently and exercised less regularly (34% vs 44%; p < 0.05) than those without complications. These findings suggest that diabetic people's smoking, drinking and exercise habits are rather similar to general people's. However, diabetic women seem to take risk factors for developing complications into consideration more than men, which could reflect a true gender pattern and/or be an effect of worrying more about diabetes. PMID- 9360274 TI - Incidence of long-term sick-listing in an urban area of Sweden and its relationship with demographic data of the population. AB - By checking the card indexes of seven out of twelve Social Insurance Offices covering 66% of the total wage-earning population in the city of Goteborg the patients recorded for 90 days of continuous sick-listing were classified into four diagnostic categories according to the doctor's certificate: "non-specific pain" and "specific pain" of the musculoskeletal system, "other pain" and "non pain" diagnoses. The overall yearly incidence of 90 days' sick-listing averaged 5.4%. A significant correlation was found between the incidence of 90 days' sick listing due to "non-pain" and musculoskeletal pain diagnoses and the proportion of demographic characteristics of the areas. The hypothesis of presuming the highest association between non-specific pain diagnoses and demographic factors was rejected. PMID- 9360273 TI - Sociodemographic characteristics of female habitual benzodiazepine consumers in the catchment area of a health care centre. PMID- 9360275 TI - Sick-leave among women and the role of psychiatric disorder. AB - The aim was to assess sick-leave among women in relation to psychiatric disorder. A stratified population-based sample of women in Gothenburg were interviewed and diagnoses were made according to DSM-III-R. Sick-leave data was obtained for a ten year period. Women with psychiatric disorder had higher rates of sick-leave, compared to women without such disorders, in analyses taking into account age, socio-economic status, physical health, marital status and motherhood. Presence of psychiatric and physical illness were both independently associated with higher sick-leave. Highest sick-leave was found among those with a combination of psychiatric and physical morbidity. Psychiatric disorder is an important factor in sick-leave among women, especially regarding length of absence. PMID- 9360276 TI - Work load, job control and risk of leaving work by sickness certification before delivery, Norway 1989. AB - Sickness absence in pregnancy has been shown to be associated with strenuous working conditions and parity. So far, few studies have made adjustments for possible interaction and confounding. Such adjustments are needed to more precisely identify targets for preventive measures. We have, therefore, in a representative population of pregnant employees in Norway 1989, computed adjusted odds ratios for leaving work by sickness absence more than three (LSC > 3) and eight (LSC > 8) weeks before delivery according to working conditions identified as risk factors in earlier studies; adjusted for job control, domestic conditions and sickness absence the year prior to pregnancy. The cumulative percentage of LSC > 8 and LSC > 3 was 26.4 and 51.1. Ergonomically strenuous postures and heavy lifting increased the risk of both outcomes. In addition, shift work and hectic work pace increased the risk of LSC > 3. Influence on breaks reduced risk. Only para experienced reduced risk of LSC when working part-time. Sicklisting the year prior to pregnancy had no confounding effect, which suggest that pregnancy represents a new incompatibility with work. Preventive measures should address work postures and heavy lifting, as well as conditions influencing the woman's control with her time. PMID- 9360278 TI - Health examinations and health services for asylum seekers in Sweden. PMID- 9360277 TI - War victims in need of physical rehabilitation in Croatia. AB - A Rehabilitation Information System was created in July 1993 in order to register war victims in need of physical rehabilitation all over Croatia. The system is currently operating and presented data covers the period from July 1991 to July 1995. Approximately 15,000 questionnaires had been completed and returned from medical institutions on in total 8589 disabled war victims in need of rehabilitation. People with severe disabilities comprised about 20% of all in need of rehabilitation. Those reported injured were 3.5 times more than those in need of physical rehabilitation. Most common types of injuries were fractures with a permanent disabling condition (3109 persons), peripheral nerve injuries (1213 persons) and amputations (956 persons). Traumatic brain injuries were registered for 594 and spinal cord injuries for 262 persons. Causes of injuries were explosive devices (such as mines, mortar shell shrapnel, etc.) in 37% of cases, bullets in 22%, accidents in 7%, other (such as fire, blast injuries, etc.) and unknown causes in 34%. PMID- 9360279 TI - Doctors' attitudes towards empirical data--a comparative study. AB - In the assessment of the effects of medical technologies, the focus is most often on the quality of the empirical data. In order to shed light on the question whether medical researchers are really so empirically oriented we conducted the following study. 600 questionnaires were sent by mail to three groups, selected at random: 1) pre-clinical researchers; 2) clinical researchers who received research grants from The Swedish Medical Research Council; and 3) general practitioners. The questionnaire was built around three cases concerning the assessment of the effects of: a) H-2-receptor antagonists, b) coronary by-pass surgery and c) the homeopathic treatment of hay fever. The results indicate that there are rather small differences in how the three groups assessed the three technologies and larger differences within one and the same group concerning different cases. The tendency is that the more one considers that empirical data should be assessed independent of theoretical considerations, the higher are the demands which are placed on the quality and quantity of the empirical documentation, and vice-versa. PMID- 9360280 TI - Comparison between blood analysis and police assessment of drug and alcohol use by injured drivers. AB - Official statistics for alcohol/drug use by drivers can influence the introduction of intervention measures against impaired driving. Thus, the validity of official statistics is important. Since official statistics are based on police assessment of inebriation, the present study was aimed at investigating this issue by comparing blood analysis with the rate of police detection of alcohol/drug use by injured drivers. All injured motor vehicle drivers who were hospitalized (HD) (Umea: n = 104) and all fatally-injured drivers (FD) who were autopsied (Umea, Northern Sweden: n = 110; Gothenburg, Western Sweden: n = 133) from May 1991 through Dec 1993 were tested for alcohol and both licit and illicit drugs. The findings of the blood analyses were compared with police assessment of inebriation. In the HD, the police suspected inebriation in 13% (n = 13) whilst blood analyses showed drug and or alcohol in 18% (n = 19) of the drivers (sensitivity 69%; specificity 97%). In the FD, the police suspected inebriation in 7% (n = 16) of the drivers whilst blood analyses showed drug and/or alcohol in 23% (n = 57) of the drivers (sensitivity 53%; specificity 100%). The blood alcohol-positive HD who the police suspected to be inebriated had significantly higher mean blood alcohol concentrations than those not suspected. To avoid biased statistics, official statistics on inebriation of injured drivers should be based on blood analysis of drug/alcohol and not on police assessment. PMID- 9360281 TI - The importance of accurate diagnosis and vigorous care of the patient with liver disease and gastrointestinal hemorrhage. AB - Gastrointestinal hemorrhage in the patient with liver disease is often massive and life threatening. Although varices are the most likely cause of hemorrhage, other sources, such as peptic ulcer disease, Mallory-Weiss tears, and portal hypertensive gastropathy, are common. As liver disease is an important risk factor for intractable bleeding and death in patients with gastrointestinal hemorrhage, outcome in these patients is often poor regardless of the cause of the bleeding. Essential elements of initial therapy include prompt and adequate intravascular volume replacement, correction of severe anemia and coagulopathies, and adequate airway management. After initial resuscitation, urgent endoscopy is required to secure the diagnosis and to deliver endoscopic therapy if possible. The specific form of therapy will differ depending on the lesion encountered. Adjunctive measures, such as the administration of antibiotics and drugs that reduce portal pressure, including octreotide, may also improve outcome. Clinical and endoscopic information can be used to predict first bleeding in patients with liver disease. A large body of data supports the use of beta-blockers in the prevention of first bleeding in patients with known varices. PMID- 9360283 TI - The management of the cirrhotic patient after transjugular intrahepatic portosystemic shunt. AB - Transjugular intrahepatic portosystemic shunts (TIPS) achieve portal decompression in a manner analogous to side-to-side surgical portacaval shunts but avoid the risks of general anesthesia and major surgery. These considerations have popularized this procedure for the treatment of refractory variceal hemorrhage. However, its increasing use has also led to the recognition of both expected as well as unexpected complications associated with TIPS. Also, the natural history of cirrhosis and portal hypertension after TIPS has now been well described. Such data allow optimizing management strategies for individual patients after TIPS placement. The use of TIPS for active variceal bleeding and the clinical factors influencing subsequent management are discussed in this article. PMID- 9360282 TI - Endoscopic management of esophageal variceal hemorrhage: injection, banding, glue, octreotide, or a combination? AB - Bleeding from esophageal varices presents a considerable challenge to clinicians. Adequate fluid resuscitation must be undertaken before urgent endoscopy. Pharmacotherapy of acute variceal hemorrhage consists of either vasopressin plus nitroglycerin or intravenous octreotide. Vasopressin should not be used alone because of a high incidence of side effects such as cardiac and/or visceral ischemia. Band ligation appears superior to sclerotherapy primarily because of decreased rebleeding from varices and decreased esophageal stricture formation among patients undergoing band ligation. Future trials with newer sclerosant agents, such as cyanoacrylate, are anxiously awaited. PMID- 9360285 TI - Relationship factors and depressive symptomatology associated with mild and severe husband-to-wife physical aggression. AB - This study uses a gender-specific approach to investigate the association among relationship factors, depressive symptomatology and husbands' marital violence in 327 couples who attended a marital therapy clinic. Both spouses reports were used to group couples according to husbands' verbal (VA), mild physical (MA), and severe physical (SA) aggression as measured by the Conflict Tactics Scale (Straus, 1979). Frequency of aggression and spouses' perceptions about their partners' communication skills during conflict (i.e., use of hostile, verbally aggressive and avoidant conflict styles) were different for all groups. Reports on marital quality, conflict management style, cognitions about marriage, and individual affective state were more negative for both spouses when husbands were severely physically aggressive. Wives in the SA group were most likely to believe that partners cannot change. Discriminant function analysis provided substantial prediction of group membership when husbands were verbally or severely aggressive, but weaker prediction when husbands engaged in mild physical aggression. The limits of current measures of dyadic processes for marital violence research are discussed. PMID- 9360284 TI - Management of ascites in the patient with portal hypertension with emphasis on spontaneous bacterial peritonitis. AB - The reintroduction of paracentesis has modified the way in which patients with ascites are treated. Transjugular intrahepatic portosystemic shunt can be an alternative treatment for patients with refractory ascites and for those patients with hepatorenal syndrome, although more studies are needed to clarify its usefulness and safety. The use of more potent and less nephrotoxic antibiotics together with an earlier diagnosis have improved the outcome of patients with spontaneous bacterial peritonitis (SBP). Oral antibiotics can be used in patients with SBP and good clinical conditions with an efficacy similar to that obtained with intravenous antibiotics. Prophylactic antibiotics in SBP should be restricted to cirrhotic patients at high risk, including bleeding cirrhotic patients, those with a past history of SBP, and those with low protein content in ascitic fluid. This chapter describes the management of ascites in patients with portal hypertension. PMID- 9360286 TI - The role of blame, distress, and anger in the hypermasculine man. AB - Research has demonstrated an association between the hypermasculine personality pattern and a history of sexually aggressive behavior. This study was conducted to examine emotions experienced by hypermasculine or macho men when prevented from attaining a goal relevant to their sense of attractiveness and sexuality by a woman. It was hypothesized that macho males would respond to high and moderate threats to their masculine identity with greater blame and anger than nonmacho males. Macho men's blame was hypothesized to mediate the transformation of negative emotions such as distress into anger. After screening with the Hypermasculinity Inventory, 34 high hypermasculine and 36 low hypermasculine men were assigned to one of three experimental conditions in which the feedback received from a female partner was either highly threatening, moderately threatening, or neutral in nature. Measures of emotion and blame were collected after the men received their feedback. Results of the study indicated that macho and nonmacho men differed only in the moderate threat condition. Macho men in this condition reported greater anger yet less blame than the nonmacho men. The pattern of results is most consistent with Berkowitz's cognitive neoassociationistic model of emotion, which does not require blame for anger to occur, as does Lazaru's cognitive-motivational-relational theory of emotion. Results of the study suggest that anger in macho men is associated with the level of surprise in a situation. PMID- 9360287 TI - Client personality disorders affecting wife assault post-treatment recidivism. AB - Previous evaluations of wife assault treatment outcome have focused generically on whether groups "succeed" or not without a clear criterion of what constituted success. The present study examines the question for whom groups generate the greatest reduction in post-treatment abuse and for whom they work least well. It was found that certain types of personality disordered men had the worst post treatment prognosis. Specifically, men with high scores on borderline personality, antisocial personality, and avoidant personality fared least well after treatment. However, taken as a generic group, men in treatment had significantly reduced post-treatment abusiveness whether reported by themselves or their wives. PMID- 9360288 TI - Estrangement, interventions, and male violence toward female partners. AB - The primary objective of this paper is to integrate three relatively distinct lines of research on male violence towards intimate female partners. First, the relation between conjugal violence and estrangement is examined. We found them to be positively associated, but they can vary independently. Second, we examined the association between estrangement and interventions. Estrangement was found to be associated with private, private/public and mainly public interventions depending upon the level of estrangement. High levels of estrangement are strongly but not invariably associated with ending the relationship. Third, we reviewed the link between interventions and violence. Interventions which empower battered female partners are most effective in ending male partner violence. Taken together, the findings tend not to support hypotheses derived from the theory of male proprietariness. Implications for social policy are discussed in the final segment. PMID- 9360289 TI - Predicting the fear of assault at school and while going to and from school in an adolescent population. AB - Recent research investigating the fear of crime has shown that when crime and behavior-specific measures of fear are utilized, the young are more likely than the elderly to be the most fearful. Research investigating the etiology of fear within adolescent populations, however, remains very limited. Using a sample of over 10,000 junior high and high school students from a supplement to the National Crime Victimization Survey, this paper examines the factors contributing to students' fear of assault both at school and while going to and from school. Results indicate that recent victimization experiences, the presence of a violent subculture at the school (e.g., gang presence and attacks on teachers) and availability of drugs/alcohol were related to fear in both contexts. The predictability of fear from individual characteristics, however, was context specific. Contrary to findings from earlier research, it was found that young females were not more fearful than their male counterparts in all contexts. While they were more fearful of an attack while going to and from school, there were no differences in fear levels while at school between males and females after controlling for other environmental and experiential factors. Conclusions largely support the contention that fear is a rational calculation based on objective criteria. Moreover, results underscore the need for more specificity when operationalizing the context and content of fearfulness. PMID- 9360290 TI - Sexual coercion in gay/lesbian relationships: descriptives and gender differences. AB - A sample of 162 gay males and 111 lesbians (N = 273) completed a survey measuring the frequency of sexually coercive acts occurring within gay and lesbian relationships. Several hypotheses were proposed to clarify earlier findings and to explore gender differences in the data. Contradicting earlier studies' findings that lesbians experience sexual coercion at higher rates than gay men, the results of this study suggest lesbians are not more likely than gay men to be classified as victims of sexual coercion. Gay men also were found to experience a significantly higher mean number of coercive experiences. Other analyses specific to the type of coercion experienced and the severity of the sexual coercion outcomes (penetration) revealed no gender differences, however. Limitations and directions for future research are discussed. PMID- 9360291 TI - Validation of the Keane MMPI-PTSD Scale against DSM-III-R criteria in a sample of battered women. AB - The Keane, Malloy, & Fairbank (1984) MMPI-PTSD Scale has proven to be a reliable and valid measure of posttraumatic stress disorder (PTSD) in combat veterans. However, few studies have examined the MMPI-PTSD Scale's validity in civilian trauma victims, including battered women. In the present study, 46 battered women who completed the MMPI-PTSD Scale were assigned to PTSD-Positive and PTSD Negative groups based on a structured diagnostic interview and then contrasted on the MMPI-PTSD Scale. Significantly higher scores on the scale were found in the PTSD-Positive group. Also, a cutoff score of 22 on the MMPI-PTSD Scale correctly classified 80.4% of the sample. Correlations between the MMPI-PTSD and DSM-III-R criteria suggest that the scale is moderately sensitive to many of the symptoms particularly those involving intrusion and psychological arousal, comprising the diagnosis of PTSD. This investigation provides further support for the validity of the MMPI-PTSD Scale and its utility in screening battered women for PTSD. PMID- 9360293 TI - Laparoscopic cholecystectomy for a metastasis of a malignant melanoma in the gallbladder. AB - In a 25-year-old woman who was operated for superficial spreading malignant melanoma two years ago a slowly growing tumor in the gallbladder was detected sonographically. Since further screening for metastatic disease was negative the gallbladder was removed laparoscopically. To our knowledge this is the first laparoscopic cholecystectomy for a metastasis of a malignant melanoma in the gallbladder. PMID- 9360292 TI - Long-term survival analysis of gastric cancer limited to the subserosa. AB - Long-term survival following surgery for gastric cancer limited to the subserosa was analyzed. Between 01.01.1984 and 30.06.1995. 265 patients were operated for gastric cancer that did not invade beyond the subserosa. Extended lymphadenectomy was performed in all cases and was constant as all patients were operated by only two surgeons. The survival outcome was analyzed with particular regard to the exact depth of tumor infiltration and lymph node involvement. The percentage of patients with positive lymph nodes increased drastically from 1.7% for mucosal invasion to 22.7% for submucosal tumor involvement. A further substantial increase was observed from 34.3% for involvement of the muscularis propria to 66.1% for subserosal involvement. The 10-year tumor specific survival rate for tumors limited to the mucosa was 100%, for submucosa and muscularis propria invasion 79.3% and 72.9% respectively, for subserosal involvement 10-year survival was 54.6%. In multivariate analysis of pathohistological variables only pT- and pN-categories according to the UICC were found to have independent prognostic influence on survival. Long-term survival indicates that gastric cancer limited to the mucosa may well be treated with a less radical approach. Gastric cancer of the submucosa and muscularis propria both have a similar good long-term prognosis with radical surgery alone whereas cancer of the subserosa probably requires some form of adjuvant therapy. PMID- 9360294 TI - Pancreatitis in systemic scleroderma. AB - We report the case of a 61-year-old woman, who suffered from abdominal pain, nausea, vomiting and fever. She had a past medical history of acute rheumatism, pyelonephritis and systemic scleroderma. Since 1971 she was hospitalized many times because of recurrent abdominal pain with increased serum amylase and lipase values. On admission, she was in distress and demonstrated clinical signs of acute pancreatitis. The link between systemic lupus erythematosus and acute pancreatitis is discussed in view of the reported cases of the world literature. PMID- 9360295 TI - Anionic polymers in cell walls of gram-positive bacteria. AB - Information on the prevalence, compositions, and structures of anionic carbohydrate-containing polymers of cell walls of Gram-positive bacteria is summarized. The data suggest that these polymers are important for normal functioning of bacterial cells and require further studies. Structural data on teichoic acids found in the literature published over the last few years are discussed. This is a very diverse class of polymers whose structure-specific pathways of degradation were studied and NMR spectra were examined. Unique comprehensive tables of 13C-NMR spectroscopic data (mainly obtained by the authors) on these polymers are given in the Appendix. Other tables summarize data on teichuronic acids, sugar-phosphate polymers, acid polysaccharides, and structural variants of bonds between acid polysaccharides and peptidoglycans known from the literature. Functions of anionic polymers and their possible chemotaxonomic applications are discussed. PMID- 9360296 TI - Purification and partial characterization of L-fucose-specific lectin from fruit bodies of Peziza badia Merat. AB - An L-fucose-specific lectin from fruit bodies of the ascomycete Peziza badia Merat, was purified by affinity chromatography on agarose-coupled human ovariomucin (serotype H). This lectin binds L-fucose but is not specific to erythrocytes of blood group O(I), similarly to the lectin from Aleuria aurantia ascomycete. Unlike L-fucose-specific plant lectins, the lectin from P. badia binds with human thyroglobulin and mannofucogalactans of aphyllophoric fungi; this suggests that the lectin interacts with L-fucose located inside the polysaccharide chain of the glycoconjugates. Thus, the immunochemical properties of the lectins from P. badia and A. aurantia are similar. PMID- 9360297 TI - Specific cleavage of hybrid proteins by proteinase encoded by the KEX2 gene. AB - A method for isolation of the KEX2-gene-encoded membrane-bound proteinase from alpha-cells of Saccharomyces cerevisiae yeast has been modified. The isolated enzyme hydrolyzes peptides and proteins with basic amino acid pairs which are cleaved at the C-ends of their peptide bonds. Because KEX2 proteinase is located within the Golgi compartment, it may be isolated by differential centrifugation of broken cells at 7000g for 15 min and at 20,000g for 15 min. By extracting the fraction that contains the active enzyme by a detergent solution, a protein has been obtained with specific activity 30 times higher than that of the membrane extract prepared according to the standard technique. This protocol decreases the number of steps required to isolate the enzyme. The effects of pH and inhibitors on KEX2 proteinase-catalyzed hydrolysis of Ac-Leu-Lys-Arg-pNA were studied. KEX2 proteinase can participate in peptide hormone processing because it cleaves human proinsulin at the peptide bond between Arg32 and Glu33. The KEX2 proteinase can specifically cleave large recombinant proteins, for example, a protein consisting of a gamma-interferon fragment linked to HIV1-proteinase via a Lys-Arg-containing peptide. PMID- 9360298 TI - Assessment of dot-blot ELISA sensitivity on membrane sorbent using various peroxidase substrates. AB - The sensitivity of the peroxidase reaction in dot-blot ELISA significantly depends on the substrate. The highest sensitivity is observed using benzidine and diamine-phenol combinations as the substrates due to the reaction of the coupled oxidation (NADI). PMID- 9360299 TI - Site-specific endonucleases RspLKI and RspLKII from Rhodococcus species LK2 are isoschizomers of SphI and BamHI. AB - Two site-specific endonucleases, RspLKI and RspLKII, have been isolated and purified to functional homogeneity from the soil bacterium Rhodococcus species LK2. RspLKI recognizes the 5'-GCATG decreases C-3' DNA sequence and RspLKII recognizes the 5'-G decreases GATCC-3' sequence (arrows indicate DNA cleavage sites). The isolated enzymes are class II site specific endonucleases and are isoschizomers of endonucleases SphI and BamHI, respectively. PMID- 9360300 TI - Site-specific endonuclease from thermophilic Bacillus species MK strain is isoschizomer of SalI. AB - Screening of thermophilic bacterial strains revealed a strain containing site specific endonuclease BspMKI. This endonuclease was purified to functional homogeneity during sequential chromatographic steps. The enzyme recognizes sequence 5'-G decreases TCGAC-3' on DNA molecule and is isoschizomer of endonuclease SalI. The molecular mass of BspMKI is about 45 kD. The enzyme is maximally active at 55 degrees C and MRB (50 mM NaCl, 10 mM Tris-HCl, pH 7.4, 10 mM MgCl2, 1 mM dithiothreitol) is the optimal buffer. The enzyme is highly stable and retains its activity during two weeks at room temperature. PMID- 9360301 TI - Expression of cDNA fragment encoding ligand-binding domain of human low density lipoprotein receptor in Escherichia coli cells. AB - To study structure-function relationships in low density lipoprotein receptor (LDLR), a key protein in human cholesterol metabolism, it is reasonable to operate with separate protein domains. To obtain highly purified functionally active LDLR ligand-binding domain, we have cloned the corresponding LDLR cDNA fragment in two expression plasmid vectors of Escherichia coli. We have developed methods to purify fusion and practically individual recombinant proteins and characterized the obtained products biochemically. Antibodies raised against fused with beta-galactosidase and individual recombinant protein have been shown to be efficient in identification of LDLR protein in crude lysates of human fibroblasts (cell line HT-1080). PMID- 9360302 TI - Glutamyl endopeptidase of Bacillus intermedius strain 3-19. Purification, properties, and crystallization. AB - A homogeneous glutamyl endopeptidase splitting peptide bonds of glutamic and, rarely, of aspartic acid residues in peptides and proteins was isolated from Bacillus intermedius 3-19 culture filtrate using chromatography on CM-cellulose and Mono S. The enzyme molecular mass is 29 kD and the pI is 8.4. The proteinase is inhibited by DFP. The enzyme, like other glutamyl endopeptidases, reveals two pH optima (pH 7.5 and 9.0) for casein and one (pH 8.0) for Z-Glu-pNA hydrolysis. The K(m) for the hydrolysis of the latter substrate is 6 mM. The enzyme activity is optimal at 55 degrees C. The enzyme is stable in the pH range 6.5-11.0. Its N terminal sequence shows 56% coinciding residues when compared with that of Bacillus licheniformis glutamyl endopeptidase. Crystal prisms or plates 0.25-0.3 x 0.15 x 0.07-0.1 mm have been grown using the vapor diffusion technique in a hanging drop followed by macroseeding. The crystals belong to the space group B2 with the following unit cell parameters: a = 69.59 A; b = 61.61 A; c = 56.11 A; gamma = 117.57 degrees. The X-ray data set to 1.7 A resolution has been collected on an automatic synchrotron (EMBL Hamburg Station). PMID- 9360303 TI - Comparative study of monoclonal immunoglobulin M and rheumatoid immunoglobulin M by differential scanning microcalorimetry. AB - Thermal denaturation of monoclonal immunoglobulin M (IgM) and rheumatoid immunoglobulin M (IgM-RF) and their Fab- and (Fc)5-fragments was studied by differential scanning microcalorimetry. The melting of IgM-RF started at a higher temperature than that of IgM and the maximum temperature of its main asymmetric peak of heat absorption was higher by 4 degrees C. At equal values of enthalpy, the thermal denaturation of IgM-RF and IgM consisted of four and five individual transitions, respectively, between pairs of states. The comparison of thermal denaturation parameters of Fab- and (Fc)5-fragments of IgM-RF and IgM showed a thermodynamic similarity of (Fc)5-fragments of both proteins, while their Fab fragments differed in the interaction between VL-CL and VH-CH domains. PMID- 9360304 TI - Isolation, purification, and characterization of a neutral Mg(2+)-dependent deoxyribonuclease of the Colorado potato beetle Leptinotarsa decemlineata Say. AB - A neutral Mg(2+)-dependent deoxyribonuclease from the Colorado potato beetle was isolated and characterized in physicochemical terms. An electrophoretically homogeneous preparation of the enzyme was obtained using salt fractionation, Sephadex G-100 gel filtration, and subsequent preparative isoelectrofocusing in an Ultrodex layer. The molecular weight of the purified DNase preparation (with a purification degree of 104) and its isoelectric point were 100 kD and 9.1, respectively. The enzyme activity was maximal at pH 7.2 and 46 degrees C in the presence of 10 mM Mg2+. The DNase of the Colorado beetle preferentially hydrolysed denatured DNA via the endonuclease pathway, degrading the substrate to oligonucleoside-3'-phosphates. As far as the physical and chemical properties are concerned, this Colorado beetle DNase seems different from previously investigated DNases of other insect species. PMID- 9360305 TI - Functional activation of antibodies on modification with Pd(II) coproporphyrin I N-Hydroxysuccinimide ester. AB - Metalloporphyrin-antibody conjugates provide a significant advantage over other types of conjugates in biomedical use for phosphorescence immunoassay, targeted immunotherapy, and internal imaging of malignant tumors. Monoclonal HSF102 antibody of mouse IgG2a subclass and monospecific rabbit IgG, both antibodies directed to human spleen ferritin, were modified with the new reagent Pd(II) coproporphyrin I tetra-N-hydroxysuccinimide ester. Functional study of the conjugates obtained revealed a 7- and 1.4-fold increase in the antigen binding activity for monoclonal HSF102 and monospecific IgG antibodies, respectively. For rabbit monospecific IgG, a concomitant increase in binding to anti-rabbit IgG antibodies directed to the epitopes of the CH2 domain in the Fc fragment was observed. In all cases, the maximum functional activation was found after conjugating one mole porphyrin per mole antibody. These results suggest that functional activation of the conjugates might be due to an increase in conformational flexibility of an antibody molecule after the modification. This increase in flexibility involves the Fab fragments and a pair of the CH2 domains in the Fc fragment and might be due to a significant charge shift (minus 5 charge units per modified amino group) that occurs after conjugation of an antibody with tetracarboxylic porphyrin. PMID- 9360306 TI - Comparative analysis of the molecular heterogeneity of ceruloplasmin from human blood and breast milk. AB - The content of ceruloplasmin (Cp) was determined in 96 samples of human breast milk using rocket immunoelectrophoresis and measurement of Cp oxidase activity. The concentration of immunoreactive Cp in milk decreased about 9 times during the first 20 days of lactation while the specific oxidase activity decreased only 4 times. Two-dimensional electrophoresis of purified milk Cp before and after its treatment with chelating agents showed that copper atoms in milk Cp are more sensitive to EDTA treatment that those in blood Cp. The comparison of the different lectin-binding ability of blood and milk Cp's revealed a difference in the composition of their carbohydrate chains. The mechanisms controlling the uptake of copper ions by newborns at the level of the expression of the Cp encoding gene in the mammary gland of the mother are discussed. PMID- 9360307 TI - Feeding behaviour and predation of a bat by Saimiri sciureus in a semi-natural Amazonian environment. AB - A free-ranging group of Saimiri sciureus was studied in a semi-natural forest habitat in eastern Amazonia, where behaviour patterns were broadly similar to those recorded for the species in the wild. According to focal-animal samples, the monkeys spent the vast majority of their time foraging and feeding, in particular for arthropod prey, which contributed almost half of identified food items. The predation of a small-bodied bat was also observed, although the study animals did not appear to forage systematically for chiropterans in the manner recorded for Saimiri oerstedi. PMID- 9360308 TI - Experimental field study of spatial memory and learning in wild capuchin monkeys (Cebus capucinus). AB - Despite a large body of data on diet and ranging patterns in prosimians, monkeys and apes, little is known regarding the types of information that non-human primates use when making foraging decisions. In a series of controlled field experiments, we tested the ability of wild capuchins (Cebus capucinus) at La Suerte Biological Research Station in north-eastern Costa Rica to remember the spatial positions of 13 feeding platforms and use olfactory and visual cues to identify baited (real bananas) versus sham (plastic bananas) feeding sites. The results indicate that when 'place' was predictable, the capuchins learned the spatial locations of food and non-food sites rapidly (one-trial learning). In a second experiment, the positions of baited feeding sites were random. In the absence of other information, the capuchins used the presence of a local landmark cue (yellow block) placed at reward platforms to select feeding sites. In a final experiment, there was evidence that expectations regarding the amount of food available at a platform (2 bananas vs. 1/2 banana) had a significant influence on capuchin foraging decisions. Although the capuchins were sensitive to changes in experimental conditions, when they were given conflicting cues, spatial information was predominant over other information in selecting feeding sites. PMID- 9360309 TI - Can spider monkeys (Ateles geoffroyi) discriminate vocalizations of familiar individuals and strangers? AB - In a field experiment, tape-recorded vocalizations of spider monkeys (Ateles geoffroyi) were played back to investigate whether individuals were able to discriminate between group members and strangers. Monkeys responded remarkably similarly in the two cases, with no significant difference found between the numbers of calls given by an individual, or the types of call given. However, a group was more likely to give some vocal reaction when hearing a stranger's call than when hearing one from an individual of their own community. Further, the only instances in which agonistic territorial behaviours occurred were in reaction to strangers' playbacks. No significant effects on the response given were produced by the sex of the caller, the location and time of day of the broadcast, the size of the subgroup hearing the call or the activity in which they were involved. These results are discussed with respect to acoustic, social and ecological factors that may lead to the apparent lack of vocal discrimination of strangers within the community range. PMID- 9360310 TI - Social memory in saddle-back tamarins (Saguinus fuscicollis). AB - Discrimination between male former group members and unrelated males was tested in 13 males. During tests, each subject lived in a cage connected by tunnels to 2 cages, each housing a stimulus male. Subjects used the tunnels to approach and interact with both stimulus animals. Proximity to the stimulus males, aggressive and non-aggressive contacts and exchange of tongue flicks were recorded. aggressive contacts were rare. The subjects had significantly more non-aggressive contacts with former group members than with unrelated males but exchanged significantly more tongue flicks with unrelated animals. There was no difference in proximity to either class of stimulus male. PMID- 9360311 TI - Foraging strategies among male and female marmosets and tamarins (Callitrichidae): new perspectives in an underexplored area. AB - Few studies have involved an examination of behavioural gender differences among callitrichid primates. The present paper presents consistent evidence from experimental projects, together with less formal observations, that adult females of both breeding and non-breeding status in species of marmosets (Callithrix) and tamarins (Saguinus) demonstrate priority of access to preferred and/or restricted sources of food. Differences in behavioural strategies between males and females in this regard are not only functionally plausible, but are consistent with differences in natural behaviour both in feeding ecology and social organization in species of the different genera. Behavioural propensities that relate to the behavioural strategies of males and females are also considered, together with a number of suggestions for future research that arise directly from the observations reported. PMID- 9360312 TI - Autonomic balance in Saimiri sciureus and Callicebus moloch: relation to life style. AB - Previous research has shown heart rate to be substantially higher in squirrel monkeys (Saimiri sciureus) than titi monkeys (Callicebus moloch). In order to evaluate whether species differences in heart rate can be accounted for by contrasting patterns of autonomic activity, heart rate in response to novel test conditions was compared using standard pharmacological agents that selectively block the sympathetic (propranolol) or parasympathetic (atropine) components of the autonomic nervous system. Squirrel monkeys were found to exhibit greater sympathetic response to novelty than titi monkeys. In contrast, sympathetic activity in titi monkeys, but not squirrel monkeys, was quickly counteracted by a strong parasympathetic response. Intrinsic heart rates, estimated by blocking both parasympathetic and sympathetic input to the heart, were within the ranges of values predicted by body weight. Heart rate for titi monkeys stabilizes at intrinsic heart rate, whereas heart rate for squirrel monkeys is maintained well above intrinsic heart rate in a novel environment. The contrast between species in autonomic balance is consistent with and probably contributes to each species characteristic mode of interacting with their social and non-social environment. PMID- 9360313 TI - Flight style of the black-billed magpie: variation in wing kinematics, neuromuscular control, and muscle composition. AB - Black-billed magpies (Pica pica; Corvidae) exhibit an unusual flight style with pronounced, cyclic variation in wingbeat frequency and amplitude during level, cruising flight. In an effort to better understand the underlying internal mechanisms associated with this flight style, we studied muscle activity patterns, fiber composition of the pectoralis muscle, and wingbeat kinematics using both laboratory and field techniques. Over a wide range of speeds in a windtunnel (0-13.4 m s-1), wingbeat frequency, wingtip elevation, and relative intensity of electromyographic (EMG) signals s-1 from the flight muscles were least at intermediate speeds, and increased at both slower and faster speeds, in approximate agreement with theoretical models that predict a U-shaped curve of power output with flight speed. Considerable variation was evident in kinematic and electromyographic variables, but variation was continuous, and, thus, was not adequately described by the simple two-gait system which is currently accepted as describing gait selection during vertebrate flight. Indirect evidence suggests that magpies vary their flight style consistent with reducing average power costs in comparison to costs associated with continuous flapping at a fixed level of power per wingbeat. The range of variation for the kinematic variables was similar in the field and lab; however, in the field, proportionally fewer flights showed significant correlations between wingbeat frequency and the other variables. Average flight speed in the field was 8.0 m s-1. Average wingbeat frequency was less in the field than in the windtunnel, but mean values for wingtip elevation and wingspan at midupstroke were not significantly different. Histological study revealed that the pectoralis muscle of magpies contained only fast-twitch (acid-stable) muscle fibers, which were classified as red (R) and intermediate (I) based on oxidative and glycolytic capacities along with fiber diameter. This fiber composition may be related to variation in wingbeat kinematics, but such composition is found in the pectoralis of other bird species. This suggests that the muscle fibers commonly found in the pectoralis of small to medium sized birds are capable of a wider range of efficient contractile velocities than predicted by existing theory. Future studies should explore alternative explanations for variation in wingbeat kinematics, including the potential role of nonverbal communication among cospecifics. PMID- 9360314 TI - Effects of dry season dormancy on oxygen uptake, heart rate, and blood pressures in the toad, Bufo paracnemis. AB - The cardiodynamic consequences of dry season dormancy in ectothermic vertebrates is not well known. Our hypothesis was that dormancy would reduce cardiac activity. We therefore determined oxygen uptake and cardiovascular function in aestivating toads, Bufo paracnemis, native to Sao Paulo State, Brazil. Specimens were collected and kept in the laboratory under controlled temperature and light regimes. We compared oxygen uptake, heart rate, blood pressure, rate-pressure product (RPP), and blood gases in toads during aestivation (dry winter season) and their early active season (spring). Oxygen uptake of winter toads at 25 degrees C was considerably lower than that of spring toads (winter: 24.0 +/- 1.8 ml/(kgh); early spring: 44.4 +/- 5.1 ml/(kgh); mean +/- SE; same in the following). A seasonal dichotomy was also observed at 15 degrees C although the differences was less pronounced (15.8 +/- 1.8 ml/(kgh) winter; 23 +/- 2.1 ml/(kgh) early spring). Chronic arterial cannulation permitted measurements of cardiodynamic variables without any undesired change in VO2. Heart rates of winter toads were significantly lower than those of early spring animals at both experimental temperatures (25 degrees C: winter 25 +/- 1.4 beats/min.; early spring: 35.2 +/- 5.1 beats/min. 15 degrees C: winter 15, 4 +/- 1.8 beats/min.; early spring: 23.9 +/- 2.1 beats/min). Systemic, diastolic and mean arterial pressures decreased slightly but not significantly during aestivation. We conclude that: (1) Bufo paracnemis downregulates metabolic rate during the dry season and (2) heart rate is also downregulated with little change of blood pressure. While the energetics of these responses are probably beneficial for survival during aestivation, the underlying biochemical mechanisms remain obscure. PMID- 9360316 TI - Effects of thyroxine (T4) or triiodothyronine (T3) replacement therapy on the programming of seasonal reproduction and postnuptial molt in thyroidectomized male American tree sparrows (Spizella arborea) exposed to long days. AB - This study tested the hypothesis that T3 (triiodothyronine) is the tissue-active "seasonality" hormone by determining whether T3 could mimic T4 (thyroxine) and program photostimulated thyroidectomized (THX) male American tree sparrows (Spizella arborea) for three components of seasonality (i.e., full-blown testicular growth, photorefractoriness, and postnuptial molt). Photosensitive males were radiothyroidectomized, transferred to long days 4 weeks later, and administered 14 daily injections (s.c.) of alkaline saline (V) containing 0.1, 1, or 10 micrograms T4 or T3. THX and thyroid-intact (THI) controls received only V. After 5 additional weeks on long days, all birds were tested for photosensitivity/photorefractoriness. Periodically during the experiment, primary flight feathers were scored for molt, and testis length was monitored by laparotomy. As an independent measure of reproductive (i.e., photosensitive vs. photorefractory) state, hypothalami collected at the end of the experiment were assayed for cGnRH-I (chicken gonadotropin-releasing hormone I) content. Like THI controls, THX males administered 1 or 10 micrograms T4 exhibited full-blown testicular growth and then regression, initiated molt, and had low hypothalamic cGnRH-I, indicating that photostimulated birds that received mid- or high-dose T4 replacement therapy had been programmed for all three components of seasonality. On the other hand, both THX controls and THX males administered low-dose (0.1 microgram) T3 replacement therapy exhibited only modest testicular growth, signifying that neither group had been programmed for any component of seasonality. By contrast, photostimulated THX males that received 0.1 microgram T4, or 1 or 10 micrograms T3, were programmed for testicular growth, but not for photorefractoriness or molt. Collectively, these results show that subcutaneously administered T3 mimicked T4 imperfectly and suggest either that T3 does not program photostimulated male tree sparrows for photorefractoriness and postnuptial molt, or that T3 does not cross the blood-brain barrier as efficiently as does T4. PMID- 9360315 TI - Metabolic effects and cellular volume responses induced by noradrenaline in nucleated erythrocytes. AB - The mechanism of adrenergic swelling, cAMP accumulation and associated Na+ and K+ concentration changes was investigated in amphibian Rana ridibunda erythrocytes. The addition of noradrenaline to an isotonic suspension of red cells of frog Rana ridibunda in the presence of the phosphodiesterase inhibitor isobutyryl methylxanthine (IBMX), induced a significant increase of the cell volume. Forskolin treatment showed analogous results. The removal of the Na+ from the incubation medium, inhibited the volume changes caused by either noradrenaline or forskolin. Under the same conditions a more than two-fold increase of lactate formation, 260% increase of glucose consumption and accumulation of cAMP were found. These effects are specific and rapid. The peak of lactate production at 7.5 min was followed by a slow further decrease, whereas cAMP reached a plateau after 15 min. The increased glycolytic rate is probably the consequence of an activation of phosphofructokinase by cAMP. When the red cells were incubated in the presence of either noradrenaline or the cAMP analog, dibutyryl-cAMP the intracellular concentration of Na+ was significantly increased by the first 7.5 min of incubation compared with the initial values. Both the adrenergic activation and dibutyryl-cAMP treatment induced an intracellular decrease in the K+ content by 15%. In the presence of amiloride the Na+ and the K+ content of erythrocytes remained unaltered. Cellular swelling may be a prerequisitive for activation of Na+ and K+ movements. These findings suggest a regulatory role of cAMP in the energy metabolism of Rana ridibunda erythrocytes. In addition, the adrenergic responses were rapid and specific to alpha 1 and beta-antagonists. PMID- 9360318 TI - Sperm storage in the spermatheca of the red-back salamander, Plethodon cinereus (Amphibia: Plethodontidae). AB - In northern Indiana, the mating season of Plethodon cinereus occurs after hibernation from March until June, when oviposition begins. During the mating season, a female stores sperm in its spermatheca, a compound tubular gland in the roof of the cloaca. The apical cytoplasm of the spermathecal epithelium is filled with large secretory vacuoles whose product is released while sperm are stored. Females induced to oviposit in June and July by injections of human chorionic gonadotropin (hCG) still retain much sperm 1 month after oviposition, but secretory vacuoles are absent in all specimens sacrificed in July and August. Instead, some sperm are embedded in the spermathecal epithelium with resultant spermiophagy involving lysosomes. A female sacrificed in September 2 months after oviposition possesses scant sperm, but spermiophagy alone does not seem extensive enough to account for the decrease in sperm numbers. Females sacrificed in October prior to hibernation lack sperm in their spermathecae; some secretory vacuoles are present, but they are not as numerous or as enlarged as in specimens collected in March and May. Inter- and intrafamilial differences in the cytology of sperm storage may not be phyletically informative at the family level but related to species-specific reproductive adaptations. PMID- 9360317 TI - Development of olfactory marker protein and N-CAM expression in chemosensory systems of the opossum, Monodelphis domestica. AB - Using olfactory marker protein (OMP) and neural cell adhesion molecule (N-CAM) immunohistochemistry, the present study describes development of olfactory and vomeronasal systems in pre- and postnatal opossums, Monodelphis domestica. As revealed by OMP expression, development of the main olfactory system precedes that of the vomeronasal system by 1-2 weeks. OMP is expressed throughout (homogeneously) the nerve and glomerular layers of the main (MOB) but is expressed more strongly (heterogeneously) in the anterior as compared to the posterior accessory (AOB) olfactory bulb. N-CAM expression is homogeneous in both MOB and AOB. The heterogeneity in the AOB is developmentally regulated, since in the 30-day-old AOB the expression of OMP is homogeneous, becoming heterogeneous during the second month of life. Maximal expression of N-CAM precedes maximal expression of OMP in the VNS by about 2 weeks. From 7 to 21 days of age only, there is a small population of OMP-positive, N-CAM-negative olfactory and vomeronasal axon terminals that penetrate deep into the brain parenchyma, overgrowing their normal targets in the MOB and AOB, respectively. PMID- 9360319 TI - Comparative myology of the forelimb of squirrels (Sciuridae). AB - The musculature of the shoulder, arm, and forearm was studied in 19 genera of squirrels, representing the Pteromyinae (flying squirrels) and all 7 tribes of the Sciurinae (tree and ground squirrels). The objective was to locate derived anatomical features of functional or phylogenetic significance and to determine how much morphological variation underlies the diverse locomotor behavior of squirrels, which includes terrestrial and arboreal bounding, climbing, digging, and gliding. The fossil evidence suggests that arboreality is primitive for squirrels, and in fact tree squirrels appear to represent the primitive sciurid morphology. Ground squirrels are less uniform and exhibit a few derived features, including a clavobrachialis muscle not seen in other squirrels. Pygmy tree squirrels, which have evolved independently in three tribes, exhibit convergence of forelimb anatomy, including the loss or reduction of several muscles in the shoulder and forearm. The forelimb anatomy of flying squirrels is the most derived and differs from that of tree squirrels in details of shoulder, arm, and forearm musculature. Some of these muscular differences among squirrels have phylogenetic significance, being shared by closely related genera, but none has significance above the tribal level. Many of the differences suggest a variety of changes in function that are amenable to further study. PMID- 9360320 TI - Morphological conservation of limb natural pendular period in the domestic dog (Canis familiaris): implications for locomotor energetics. AB - For better understanding of the links between limb morphology and the metabolic cost of locomotion, we have characterized the relationships between limb length and shape and other functionally important variables in the straightened forelimbs and hindlimbs of a sample of 12 domestic dogs (Canis familiaris). Intra animal comparisons show that forelimbs and hindlimbs are very similar (not significantly different) in natural pendular period (NPP), center-of-mass, and radius of gyration, even though they differ distinctly in mass, length, moment-of inertia, and other limb proportions. The conservation of limb NPP, despite pronounced dissimilarity in other limb characteristics, appears to be the result of systematic differences in shape, forelimbs tending to be cylindrical and hindlimbs conical. Estimating limb NPP for other species from data in the literature on segment inertia and total limb length, we present evidence that the similarity between forelimbs and hindlimbs in NPP is generally true for mammals across a large size range. Limbs swinging with or near their natural pendular periods will maximize within-limb pendular exchange of potential and kinetic energy. As all four limbs of moderate- and large-size animals swing with the same period during walking, maximal advantage can be derived from the pendular exchange of energy only if forelimbs and hindlimbs are very similar in NPP. We hypothesize that an important constraint in the evolution of limb length and shape is the locomotor economy derived from forelimbs and hindlimbs of similar natural pendular period. PMID- 9360321 TI - Interrelationships between cytoplasmic Ca2+ peaks, pollen hydration and plasma membrane conductances during compatible and incompatible pollinations of Brassica napus papillae. AB - We have investigated Ca(2+)-involving cell signaling, plasma membrane potentials and conductances and callose formation during early stages of pollination of papillae of Brassica napus. Using fluorescence imaging of calcium green-1, we found that application of a range of pollen types and controls all rapidly produced small localized peaks in papillar cytoplasmic [Ca2+]. This response was more frequent in compatible than incompatible interactions and was correlated with subsequent hydration of the applied pollen grains, indicating that it may be a differential prerequisite of the compatible signaling pathway leading to successful pollinations. In contrast, a slight trend to increased plasma membrane conductance (but with no indications of action potential-like responses) and also callose deposition in papillae adjacent to pollen grains followed pollination in both SC and SI interactions, indicating that alterations in plasma membrane permeability and callose deposition during early phases of pollination are not primary determinants of the fate of attempted pollinations. PMID- 9360322 TI - Changes in H(+)-pumps and a tonoplast intrinsic protein of vacuolar membranes during the development of pear fruit. AB - Vacuolar H(+)-ATPase (V-ATPase) was purified from pear fruit and antibodies were raised against the subunits of 55 and 33 kDa. Antibodies against mung bean H(+) pyrophosphatase (V-PPase) and radish VM23, which is a tonoplast intrinsic protein (TIP) and a water channel, cross-reacted with the vacuolar membrane proteins of pear fruit. To clarify the roles of these proteins in development of pear fruit, we determined their levels relative to the total amount of protein by immunoblot analysis. The levels of subunits of the V-ATPase increased with fruit development. By contrast, the level of V-PPase was particularly high at the cell division stage and remained almost the same at other stages. The changes in the activities of V-ATPase and V-PPase corresponded to those in their protein levels. The ratio of V-PPase activity to V-ATPase activity indicated that V-PPase is a major H(+)-pump of the vacuolar membranes of young fruit and that the contribution of V-ATPase increases with fruit development, finally, V-ATPase becomes the major H(+)-pump during the later stages of fruit development. The level of a protein analogous to VM23 (VM23P) was especially high during the active cell-expansion stage in young fruit, and VM23P might, therefore, play an important role in the rapid expansion of cells as a vacuolar water channel. Our results show that the levels of V-ATPase, V-PPase and VM23P change differently and reflect the roles of the respective protein in the development of pear fruit. PMID- 9360323 TI - Isolation and characterization of matrix associated region DNA fragments in rice (Oryza sativa L.). AB - To investigate the interactions between chromosomal DNA and nuclear matrices in higher plants, matrix associated regions (MARs) of rice (Oryza sativa L.) DNAs were cloned. First, we prepared nuclear matrices from isolated nuclei by digesting them with EcoRI and then extracting with 2 M NaCl. About 6% of the total DNA remained in the nuclear matrices after this digestion and extraction. The residual DNA fragments in the nuclear matrices were cloned. Some of the cloned DNA fragments showed binding to certain nuclear proteins. One of the MAR fragments contained sequences related to known consensus motifs and a hairpin loop structure. A method is presented for isolation of matrix associated region (MAR) DNAs from plant cells. PMID- 9360324 TI - beta-Glucosidase in the indigo plant: intracellular localization and tissue specific expression in leaves. AB - beta-Glucosidase of indigo plant (Polygonum tinctorium) has a high substrate specificity for indican (indoxyl beta-D-glucoside). To examine the localization of this beta-glucosidase, we fractionated the cells of the leaves and analysed them immunocytochemically. Immunoelectron micrographs with specific antibodies against the beta-glucosidase clearly showed that the beta-glucosidase was localized in the stroma of the chloroplasts in mesophyll cells, but not in the thylakoid membrane. Chloroplasts were isolated from the crude homogenate of the fresh leaves by Percoll density gradient centrifugation and then subjected to suborganellar fractionation. beta-Glucosidase activity was specifically detected in the stromal fraction, but not in the thylakoid membrane. This was also supported by the result of an immunoblot of the fraction with anti-beta glucosidase antibodies. The beta-glucosidase was immunocytochemically localized in the chloroplasts of mesophyll cells, but not in any chloroplasts in marginal cells of the vascular bundle or epidermal cells; ribulose 1,5-bisphosphate carboxylase (Rubisco), a typical stromal protein, was observed in all chloroplasts in these cells. These results suggest that beta-glucosidase is tissue specific in its expression in the leaves of the indigo plant. PMID- 9360325 TI - A major root protein of carrots with high homology to intracellular pathogenesis related (PR) proteins and pollen allergens. AB - We isolated the cDNA clone coding for a major root specific protein (CR16) of carrots. The CR16 protein (154a.a.) has a high homology to intracellular pathogenesis-related (PR) proteins, stress-induced proteins and also the major allergen protein of celery (Api g1). The CR16 protein gene formed a super gene family and transcripts of this CR16 protein gene are predominant in root tissue, not in leaves or flowers. PMID- 9360326 TI - Knowledge of HIV/AIDS modes of transmission and means of protection in different European countries. AB - This study was undertaken to assess the state of the european population's knowledge on HIV transmission and means of protection. Data were delivered from different national surveys based on questionnaires administered to general population samples. The results showed that the population's knowledge on HIV/AIDS are insufficient or even incorrect. PMID- 9360327 TI - What relevance do advances in molecular biology and genetics have for epidemiology: high tech needle and thread to sew the web of causation. AB - Epidemiology has changed, during the past, from miasma versus germ theory to the studies of relationship between exposure and outcome. New definitions such as risk factors or multifactorial aetiology, and more recently web of causation, have been helpful to understand many diseases. Molecular biology and genetics advances in the past decade can be instruments that allow to investigate more deeply the web of causation. Molecular biomarkers are the new investigating mean. Examples of studies using these new techniques are presented, in many epidemiological fields: in non communicable disease with linkage and association studies, allowing experimental studies; in cancer, investigating susceptibility to the disease, early exposure to environmental carcinogens detection and specific mutational patterns in aetiological studies; in communicable disease, in particular with genetic subtyping of particular agents and causal mechanisms research. To mix up all the knowledge required to handle these techniques and epidemiology shall be profitable integrate multidisciplinary team of scientists, epidemiologists and molecular biologists together. This might be the way to approach the distribution and determinants of disease in deep but also with more clear and explicit explanation of the elaborate relationships. PMID- 9360328 TI - Identification of Listeria monocytogenes by colony hybridization test using the virulence-associated hly and inlA genes as probes. AB - We developed a method of identification of Listeria monocytogenes based on colony hybridization with nonradioactively labeled DNA probes, represented by the hly and inlA virulence-associated genes. The procedure described in this paper results simple, rapid, specific and reproducible. Since it can be performed in a short time, the above technique can be applied to detect L. monocytogenes from different source and constitutes a noteworthy and alternative tool to identify this gram-positive pathogenic bacterium. PMID- 9360329 TI - Microbiological quality of coastal sea water of Alexandria, Egypt. AB - The aim of the present study was to evaluate the quality of the seawater in Alexandria, Egypt. Samples were collected in 6 different points: Kayet Bay, El Shatby, Camp Cesar, Sporting, Beir Massoud and El Max. In total, 24 samples were analyzed. For each point the analysis included estimation of the following parameters: Esherichia coli, total coliform and fecal streptococci, Yersinia, Shigella, Salmonella, bacteriophages and enteric viruses. Just one sample (El Max) was positive for the presence of Salmonella, neither Shigella or Yersinia were isolated from any of the analyzed points. E. coli was identified in 10 samples while the ratio between total coliform and fecal streptococci showed variable results with the exception of El Max that resulted constantly high. Three samples were positive for the presence of enteric viruses: El Shatby, Beir Massoud and Sporting. The analysis of phages showed a variable pollution values. PMID- 9360330 TI - Experience with ifosfamide and etoposide combination chemotherapy in extensive disease small-cell lung cancer. AB - BACKGROUND: Ifosfamide, an isomeric analogue of cyclophosphamide, has significant activity against many human tumors including lung cancer, testicular cancer, lymphoma and sarcoma, and may be superior to its analogue. Herein, we report our preliminary experience using ifosfamide and etoposide (IE) combination chemotherapy in previously untreated patients with extensive-disease (ED) small cell lung cancer (SCLC). METHODS: Patients with histologically or cytologically confirmed SCLC, measurable or assessable ED, no previous chemotherapy or thoracic irradiation, younger than 70 years of age, Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0-3, and adequate marrow, liver, and renal functions were eligible for treatment which consisted of ifosfamide 2.0 g/m2/d given intravenously (i.v.) for 3 days with mesna 400 mg/m2/dose i.v. administered 0, 4, and 8 hours after the daily administration of ifosfarnide, and etoposide 80 mg/m2/d i.v. given for 3 days in every 4 weeks for a maximum of 6 cycles. RESULTS: Between January 1994 and February 1995, 10 patients were enrolled into the treatment. All were men with a mean age of 63 +/- 6 years. Five patients had an ECOG PS of 0 or 1, 4 patients of 2, and 1 patient of 3. A total of 45 cycles of IE were given. The mean number of cycles per patient was 4.5 +/- 2.1. Six patients completed 6 courses of therapy. Thirty-two of 45 cycles (71%) of IE were given at full doses, while the remaining 13 cycles (29%) were given at 75% of doses. Nine patients were assessable for response. Eight patients had a partial remission and one patient had stable disease. The overall response rate was 89%. The median survival was 8 months (range, 0 to 23 months) and the median failure free survival duration was 5.5 months (range, 0 to 18 months). The 1- and 2-year survival rates were 30% and 0%, respectively. Myelotoxicity was the most important toxicity, particularly neutropenia, while thrombocytopenia and anemia were mild. Five of 10 patients (50%) experienced grade 4 neutropenia, which occurred in 2 patients during the first course of IE and resulted in one patient death from early sepsis. Other nonhematologic toxicities were mild. CONCLUSIONS: Our preliminary experience demonstrates that ifosfamide is an active drug against SCLC and combination chemotherapy with IE results in similar response rate and median survival, but probably higher myelotoxicity than reported studies in patients with ED SCLC. PMID- 9360331 TI - Surgical treatment of seat belt type injury of the thoracolumbar spine. AB - BACKGROUND: Seat belt type injury of thoracolumbar spine is an uncommon injury characterized by disruption of the posterior elements of the spine. The fracture has long been treated conservatively, but progressive kyphotic deformity developed frequently. METHODS: From January, 1991 through December, 1992, 10 cases of seat belt type injury of the thoracolumbar spine were encountered at our hospital with an incidence of 8% in overall spinal fractures. Of these patients, eight patients were male and two were female, average age 30.7 years old. The causes included motor-vehicle accident in five patients, fall from height in four, and stricken by a falling electric pole in one. None of the victims of motor vehicle accidents wore seat belt. All of them received open reduction, posterior internal fixation and posterior fusion. RESULTS: After follow-up for an average of 42.2 months, the average kyphotic angulation was 5.7 degrees. Back pain and function of these patients were all rated good. None of them suffered from neurologic deficit. One patient with breakage of transpedicular screws was encountered during follow-up, but there was no complaint. CONCLUSIONS: In treating seat belt type injuries of spinal column, benefits of operation outweigh the risks. Besides, the clinical result is satisfactory and more aggressive surgical approach should be encouraged. PMID- 9360332 TI - Heart rate variability in patients with atrioventricular block. AB - BACKGROUND: Heart rate variability (HRV) analysis has been an established method for assessment of the activities of autonomic nervous system. Conventionally, the RR intervals from the surface electrocardiogram (ECG) are used for HRV analysis, however, analysis of the RR intervals may not be suitable in patients with atrioventricular (AV) node dysfunction, particularly in patients with certain degree of AV block. We used an esophageal electrode to detect PP intervals for HRV analysis in these patients. METHODS: Seven AV block patients and 13 subjects with normal AV conduction (control group) were enrolled in this study. The signals from esophageal lead, surface lead and intraatrial lead were recorded. Correlation coefficient of heart beat intervals from different leads was analyzed. Then we compared the HRV parameter recorded by esophageal lead between AV block patients and the control group. RESULTS: The AA intervals in intraatrial ECG and the PP intervals in surface ECG were poorly correlated (r = 0.489) in the AV block patients. However, intraatrial ECG was correlated well with esophageal ECG (r = 0.968). HRV with time domain decreased significantly in patients with AV block. The standard deviation of NN intervals (SDNN), pNN-50 and r-MSSD in the control group and the AV block patients were 0.035 +/- 0.006 vs. 0.021 +/- 0.016 seconds (p = 0.002), 3.210 +/- 3.120 vs. 0.050 +/- 0.040% (p = 0.027) and 0.577 +/- 0.181 vs. 0.318 +/- 0.084 seconds (p = 0.009), respectively. CONCLUSIONS: The esophageal lead recording is a non-invasive, easy and safe method to detect HRV of AV block patients whose vagal activity is abnormal. PMID- 9360333 TI - Surgical repair of Ebstein's anomaly. AB - BACKGROUND: Ebstein's anomaly represents a congenital structural deformity of the tricuspid valve associated with a wide spectrum of morphologic and physiologic abnormalities. Valvuloplasty and tricuspid valve replacement are the main surgical treatments. Plication of the atrialized right ventricle and valvuloplasty of the tricuspid valve can achieve satisfactory clinical results. Two surgical techniques, known as Danielson's and Quaegebeur's methods, are often used clinically. This study was conducted to compare the postoperative results between both methods in treatment of Ebstein's anomaly. METHODS: Valvuloplasty of tricuspid valve and the plication of atrialized right ventricle were performed in 8 out of 17 patients with Ebstein's anomaly in our hospital from January 1986 to August 1996. Danielson's method was used in six of eight patients, and Quaegebeur's method was used in the remaining two patients. There were three males and five females, aged from 8 months to 61 years (mean: 14.1 years). RESULTS: All patients achieved clinical improvement in cardiothoracic ratio and heart functional class. Cardiac arrhythmia was the likely cause of death in two patients treated by Danielson's method, and one patient developed complete atrioventricular (A-V) block postoperatively. By Quaegebeur's method, all patients survived, but a permanent pacemaker was implanted for both patients due to their preoperative complete A-V block. CONCLUSIONS: Both methods achieved satisfactory postoperative results. However, Quaegebeur's method seems to be more effective because it provided a simultaneous reconstruction of both tricuspid valve and right ventricle without the need for additional excision of the right atrium. PMID- 9360334 TI - The relation between thickened aortic valve and coronary artery disease. AB - BACKGROUND: The relationship between the site of aortic valve thickening and ipsilateral coronary artery stenosis has not been reported previously. This study was undertaken to test the hypothesis that left-sided coronary cusp thickening may be associated with a left-sided coronary artery stenosis, and also as would be in the right-sided relationship. METHODS: Two-dimensional echocardiography and cardiac catheterization were used to evaluate 420 consecutive patients. One hundred and six patients who had echocardiographic evidence of a single aortic valve thickening were studied to determine whether there was a relation between the coronary artery stenosis and the aortic valve thickening at the same side. Thickened aortic valve was defined as an aortic valve thickness to aortic wall thickness ratio > or = 1.0. Coronary artery disease (CAD) was defined as a > 50% luminal diameter narrowing of the left main coronary artery or a > 70% luminal diameter narrowing of the coronary artery other than the left main coronary artery. RESULTS: Patients with a thickened aortic valve had a greater incidence of CAD (89/132, 67.4%) than those without (141/288, 49.0%) (p < 0.05). In patients with thickened aortic valves, the incidence of CAD was 45.5% in the fifth decade, 60% in the sixth decade, 69.6% in the seventh decade and 74.1% in the eighth decade. Progressive increase of the incidence of CAD was not found in patients without a thickened aortic valve. In the 106 cases with a single aortic valve thickening, 30 patients (28.3%) had a left coronary cusp thickening; 12 of them (40%) had a left-sided coronary artery stenosis, 3 patients (10%) had right coronary artery stenosis and 7 patients (23.3%) had no coronary artery stenosis. In the 34 patients with right coronary cusp thickening, the stenosis occurred at the left coronary artery in 13 patients (38.2%), at the right coronary artery in 3 patients (8.8%) and with normal coronary artery in 5 patients (14.7%). This finding did not support the relationship between thickened aortic valve and coronary artery disease at the same side (chi 2 = 0.06, p = 0.96). CONCLUSIONS: There was a significantly greater incidence of CAD in patients with a thickened aortic valve than in those without. The incidence of CAD in patients with thickened aortic valves increased with age. There was no direct relationship observed between the site of aortic valve thickening and ipsilateral coronary artery stenosis. PMID- 9360335 TI - Response of resuscitation in multiple trauma with pelvic fracture. AB - BACKGROUND: The early management of patients with pelvic injury remains a great challenge for emergency physicians and trauma surgeons. A retrospective study was performed in this hospital to identify the clinical significance of different responses in the resuscitation of pelvic injury. METHODS: From March 1989 to May 1995, 75 patients with pelvic ring injury who had initially had unstable hemodynamic status were studied. They were divided into four groups as "good response" (GR), "delayed response" (DR), "poor response" (PR) and "no response" (NR) according to the time when hemodynamics became stable after immediate resuscitation. RESULTS: Motor vehicle accidents (MVA) had a higher incidence than other causes in the trauma mechanism. The fracture types of pelvis had no correlation with the response to resuscitation. The injury severity score (ISS) was higher in the PR group (41.7 +/- 18.3) than in the GR (17.5 +/- 8.6) or DR (19.5 +/- 17.0). The incidence of extrapelvic hemorrhage (EPH) and of mortality rates was higher in the PR group (38% and 75%, respectively), and the DR group (25% and 13%, respectively), than in the GR group (6% and 2%, respectively). CONCLUSIONS: The responses of resuscitation is a valuable parameter in the management of multiple trauma with pelvic injury. Nonoperative treatment may be tried in patients of good response to resuscitation with EPH. In those patients with poor or delayed response, delayed extrapelvic bleeding (especially from abdominal injury) must be ruled out besides aggressive management for pelvic injury. Poor prognosis can also be expected in those patients with poor response. PMID- 9360336 TI - Neuroimages of Japanese encephalitis: report of three patients. AB - The cranial computed tomography (CT) and magnetic resonance image (MRI) studies of three Japanese encephalitis (JE) patients, 24 to 37 years of age, are reported. The initial findings of CT study were limited but initial MRI studies revealed multiple lesions involving the brainstem, basal ganglia and bilateral thalami. Follow-up MRI studies showed small residual lesions only. The result shows that MRI can delineate and detect brain lesions better than CT in patients in the acute stage of JE. The locations of lesions in MRI study are noteworthy and have a good correlation with pathologic anatomic distribution. Therefore, MRI study is helpful in early diagnosis of JE. PMID- 9360337 TI - Intraosseous epidermoid cyst in distal phalanx of finger: a case report. AB - Bone tumor in distal phalanx of finger is rare. Differential diagnosis includes glomus tumor with bone erosion, enchondroma, osteomyelitis, aneurysmal bone cyst and metastasis. We herein present a case with intraosseous epidermoid cyst in distal phalanx which has rarely been reported. PMID- 9360338 TI - Huge splenic epidermoid cyst: a case report. AB - A case is reported of splenic epidermoid cyst discovered in a 21-year-old female. The lesion was shown by abdominal ultrasonography and computed tomography to be 14 x 12 x 8 cm in size and to contain serous fluid in the lumen. The spleen was easily removed by surgery. Histopathologically, the epidermoid cyst was composed of a loosely fibrous wall and a single layer interior lining of flattened or low cuboidal epithelium, without skin appendages. The remaining splenic tissue showed mild congestive change with thickened sinusoidal stroma. Most splenic cysts have presented with symptoms related to both the size of the mass and compression of an adjacent organ. Potential complications include hemorrhage, infection, and rupture of the splenic cyst. Splenectomy is recommend to eradicate symptoms produced by the cyst and to prevent potential complications. PMID- 9360339 TI - Radiofrequency catheter modification of sinus node for inappropriate sinus tachycardia: a case report. AB - We present here, the case of a 22-year-old male suffering from persistent tachycardia for the past 3 years. His resting pulse rate was rarely below 100 beats/min, and it frequently increased to as high as 150 beats/min even after a minimal of activity. Associated symptoms included palpitation, chest tightness, dyspnea and presyncope, either during rest or with exercise. Propranolol and verapamil could not control the tachycardia. The application of radiofrequency energy to an area in the superior right atrium that demonstrated a discrete electrogram with earliest endocardial activation during tachycardia resulted in a decrease in sinus rate from 120 beats/min to 70 beats/min. Follow-up on Holter monitor, performed one month later, demonstrated an average heart rate of 84 beats/min (range 60-125). In exercise tolerance test, the patient exercised for 9 minutes, achieving a maximum heart rate of 140 beats/min. This patient remained asymptomatic without any antiarrhythmic drug during the 3-month follow-up period. Medical management in case of patients showing disabling inappropriate sinus tachycardia refractory, sinus node modification could be considered as an suitable alternative to complete atrioventricular junctional ablation. PMID- 9360340 TI - Acceptability of rice-based and flavoured glucose-based oral rehydration solutions: a randomized controlled trial. AB - The acceptability of prepackaged rice-based (Oresol-R) and flavoured (Oresol-F) glucose-based oral rehydration salts (ORS) solutions was compared with that of standard glucose-based ORS (Oresol-G) in a randomized field trial. Additionally, it is determined if presenting rice-based ORS as a solution that would help stop diarrhoea (Oresol-K) enhanced its acceptability. A total of 437 non-dehydrated children aged less than five years presenting to health centres with acute diarrhoea were randomly assigned to the three ORS groups. Acceptability was determined by the amounts of ORS consumed at home by children still with diarrhoea on 24- or 48-hour follow-up. The amounts of ORS consumed by children given Oresol-R (54 [95% CL 38-70] mL/kg/24 h) and Oresol-F (47 [24-70]) were similar to the amount of Oresol-G (44 [32-56]). ORS consumption was not affected by the child's age, nutritional status, feeding before the episode, duration of diarrhoea at health centre visit, maternal education and previous ORS use. Informing the caretaker that rice-based ORS would help stop diarrhoea did not lead to increased consumption of the solution (Oresol-R 54 [38-70] mL/kg/24 h; Oresol-K 50 [32-68]). Solution preparation was likewise similar among the treatment groups. Reactions to the different ORS types were generally favourable but did not differ between the groups. PMID- 9360341 TI - Human colostrum IgA antibodies reacting to enteropathogenic Escherichia coli antigens and their persistence in the faeces of a breastfed infant. AB - IgA antibodies reacting to enteropathogenic Escherichia coli (EPEC) antigens in human colostrum and their role in the inhibition of EPEC adherence to HEp-2 cells were studied. Colostrum IgA was isolated with a Sepharose anti-IgA column. IgA depleted colostrum lost its inhibitory effect on EPEC adhesion, while the IgA enriched eluate was a potent adherence inhibitor. The same eluate showed a significant loss of inhibitory activity after absorption with an EPEC strain showing localised adherence (LA+), but no alteration after absorption with an LA- strain. No bands were observed in Western blot analysis with LA+ absorbed eluate and with a crude extract of the EPEC strain, but the eluate absorbed with LA- showed a strong recognition of a 94-kDa band, a molecular weight equivalent to that of intimin. Colostrum antibodies reacting to non-protein antigens were not detected by Western blot analysis. The persistence of anti-EPEC IgA in the gastrointestinal tract was shown by the strong reactivity to the 94-kDa band in Western blot analysis of one mother's colostrum and her infant's faeces. These data confirm the role of colostrum antibodies in protecting the neonate against infections due to EPEC. PMID- 9360342 TI - Sequential changes in gut mucosa of rabbits infected with Vibrio cholerae O139 Bengal: an ultrastructural study. AB - Adhesion and subsequent colonisation are important events in the infection by Vibrio cholerae O139 Bengal. To determine in details the pathological changes in the gut mucosa, an epidemic strain of O139 Bengal was inoculated in a rabbit ileal loop model. Electron microscopic studies were done at different time intervals after inoculation of the strain to see the histological changes at the ultrastructural level. From 10 hours onwards, cellular invasive processes with presence of bacteria in the lamina propria and other associated inflammatory changes were revealed. PMID- 9360343 TI - Detection of non-culturable Shigella dysenteriae 1 from artificially contaminated volunteers' fingers using fluorescent antibody and PCR techniques. AB - Epidemiological studies have demonstrated that hands may be an important vehicle for transmission of shigellosis. The present study was carried out to find out the survival potential of Shigella dysenteriae 1 on fingers of volunteers. Finger surface was inoculated with 10(5) cfu of S. dysenteriae 1 and then the bacteria were detected using conventional culture, PCR and fluorescent antibody (FA) techniques after different time intervals. It was found that S. dysenteriae 1 survived for up to one hour in culturable form but up to four hours in non culturable form on human fingers. The non-culturable S. dysenteriae was detected by PCR and FA techniques. This study elaborates on the role that fingers have in the transmission of shigellae. PMID- 9360345 TI - Immature Hymenolepis nana worms in the stools of a patient treated for acute lymphoblastic leukaemia: an uncommon observation. PMID- 9360344 TI - Intestinal parasitic infections in patients with malignancy. AB - The frequency of intestinal parasitic infections was studied retrospectively in 1,029 cancer patients presenting with symptoms of diarrhoea. Intestinal parasites were diagnosed by stool examination, using both the direct and concentration techniques and also the modified acid fast stain. Parasitic infection was found in 16.5% of the cases. The majority of the patients with intestinal parasitosis had cancer of the haemopoietic system and were on anticancer chemotherapy. The most prevalent parasites were Entamoeba histolytica/Entamoeba dispar (8.5%) and Giardia lamblia (3.1%). Much more rare were Strongyloides stercoralis (0.6%), Cryptosporidium parvum (0.3%) and Isospora belli (0.1%). All the patients with intestinal parasites were negative for HIV antibodies. PMID- 9360346 TI - Bibliography on diarrhoeal diseases. PMID- 9360347 TI - Jobs for all, economic justice, and the challenge of welfare "reform". AB - Jobs for All at decent wages is not the only strategy for reducing poverty and economic inequality, but it is more desirable and more consonant with American values than a primary strategy of direct income redistribution through government benefits. To make jobs the primary strategy for people of working age, however, is not to overlook the need for certain types of income support in good times and in bad, and the important economic functions of the welfare state. Current welfare "reform" poses as a work strategy but is the very antithesis of jobs for all because it creates job seekers rather than jobs and will increase unemployment and lower wages. Economic and social benefits of full employment are identified, and criticisms of the strategy--that many current jobs are risky, boring and poorly paid--are addressed. The abiding and new obstacles to full employment are acknowledged, their seriousness assessed, and means for overcoming them proposed. The author concludes that the obstacles to jobs for all are primarily political rather than economic, and shows how the National Jobs for All Coalition is attempting to overcome them and to build a new movement for economic justice. PMID- 9360348 TI - NAFTA and occupational health: a Canadian perspective. North American Free Trade Agreement. AB - In Canada, health and safety laws are built around three worker rights which are not guaranteed by law in the United States: the right to participate in joint management-worker health and safety committees; the right to know about workplace hazards which requires consultation with the joint committee about the education and training programs; and the right to refuse hazardous work. In the context of NAFTA, health, safety and environmental laws and their enforcement, as well as the workers' compensation system, are all under attack by business leaders who cite the need to deregulate and privatize Canadian institutions in order to harmonize with the United States. The counteroffensive by the trade unions and their allies in the social justice movement is described; the struggle continues. PMID- 9360349 TI - Night driving restrictions for youthful drivers: a literature review and commentary. AB - The research literature on night driving curfews is reviewed. Driving at night involves high risk, particularly for young beginners. Although only about 15 percent of the total miles of 16-17-year-old drivers occur between 9 p.m. and 6 a.m., about 40 percent of their fatal crashes take place during these hours. Curfews that limit recreational driving at night without an adult have been found to substantially reduce nighttime crashes. Parents of teenagers strongly endorse curfews and favor earlier starting times than prevail in most jurisdictions with curfews. A night driving curfew is an essential component of graduated licensing, a system that phases in young beginners to full-privilege licensure, limiting initial driving to lower-risk situations. PMID- 9360350 TI - Personal flotation device usage: do educational efforts have an impact? AB - Boating is a popular form of recreation in the United States. Unfortunately, many people drown due to boating-related accidents each year. Since many such drowning deaths are preventable through the use of personal flotation devices (PFDs), an observational study was conducted to quantify and evaluate the number and demographics of the individuals who choose to wear life jackets in King County, Washington. Further efforts were then directed toward evaluating the effectiveness of educational campaigns focused on increasing PFD usage and general boating safety. Highly significant increases were found in the use of life preservers overall and within various subgroups of the population. Total PFD use increased from 19.8% in 1992 to 31.3% in 1994. Future studies are needed to determine the reproducibility of this data and the feasibility of incorporating similar educational efforts into other injury prevention programs nationwide. PMID- 9360351 TI - Water safety: prevention and treatment of water-related injuries and illnesses. PMID- 9360352 TI - Sharks, alligators, barracudas, and other biting animals in Florida waters. PMID- 9360353 TI - Venomous marine animals of Florida: morphology, behavior, health hazards. AB - This article reviews the dangers related to marine animal envenomations in Florida. Venomous marine animals exhibit diverse mechanisms of injury and toxicity. Information regarding the morphology, behavior, and health hazards of these dangerous organisms is presented to help medical personnel recognize, diagnose and treat marine envenomations. Hazardous marine animals discussed in this review include both invertebrates and vertebrates. Stinging invertebrate animals include sponges, coelenterates (jellyfish, hydroids, corals, and sea anemones), echinoderms (sea urchins, starfish and sea cucumbers), annelid worms (bristleworm), and mollusks (cone shells, octopi and nudibranches). Stinging vertebrates discussed include stingrays, catfish, scorpionfish, and leatherjacks. PMID- 9360354 TI - Water-related disease in Florida: continuing threats require vigilance. PMID- 9360355 TI - Scuba diving accidents: decompression sickness, air embolism. PMID- 9360356 TI - Drowning and near drowning. PMID- 9360357 TI - Accidents on the waterways: another focus for injury prevention. PMID- 9360358 TI - Cruise ship medical facilities: caveat emptor. PMID- 9360359 TI - How did a regional medical school building qualify as a National Historic Landmark? PMID- 9360360 TI - Fraud, abuse, and beyond. Costly pitfalls for physicians who serve Medicare and Medicaid patients. PMID- 9360361 TI - Hospital-based Wellness Program: a 12-year experience. AB - Our experience has taught us that our most significant contribution to the "well being" of the hospital community is the development of a forum where ideas and perhaps more important, feelings can be shared in a safe, open, and honest manner. A trust level develops among the individual committee members that facilitates a unique bonding experience. Problems may not always be solved but the emotional impact on the individual is softened by those who Share & Care. PMID- 9360362 TI - Teaching third-year medical students how to handle ethical dilemmas. PMID- 9360363 TI - The legality of waiving copayments and granting professional courtesies. PMID- 9360364 TI - [History of influenza epidemics and discovery of influenza virus]. AB - Influenza epidemics occur almost annually, sometimes taking on a global scale and turning into pandemics. According to Noble, the first clearly recorded epidemic was one that struck Europe in 1173 to 1174. In Japan the first comprehensive review of epidemic records was made by Fujikawa in the early 20th century, who listed 46 epidemics between 862 and 1868. Of the ten pandemics since the 1700s that have been certified by Beveridge nine have struck Japan as well. The human influenza A virus was discovered in 1933 soon after Shope succeeded in isolating swine influenza A virus in 1931. Since the discovery studies in the influenza have made immense progress and have contributed greatly to not only virology but also immunology and molecular biology. PMID- 9360365 TI - [Classification and nomenclature of influenza viruses]. AB - Criteria for classifying influenza viruses into genera, types and subtypes have been discussed, with reference to the 6th report of ICTC. The viruses are divided into 2 genera based on the number of the genome RNA segments. Those which contain 8 segments are further divided into types A or B, according to the antigenicity of the NP and M1 proteins. Viruses belonging to type A are finally classified into subtypes according to the serotype of the HA and NA proteins. Thirteen and nine serotypes of HA and NA, respectively, have been identified in nature, where a variety of combination is possible by genetic reassortment. Method for nomenclature of influenza viruses has also been discussed. PMID- 9360367 TI - [Ecology of influenza viruses in animals and the mechanism of emergence of new pandemic strains]. AB - Ecological studies on influenza viruses revealed that the hemagglutinin genes are introduced into new pandemic strains from viruses circulating in migratory ducks through domestic ducks and pigs in southern China. Experimental infection of pigs with 38 avian influenza virus strains with H1-H13 hemagglutinins showed that at least one strain of each HA subtype replicated in the upper respiratory tract of pigs. Co-infection of pigs with a swine virus and with an avian virus generated reassortant viruses. The results indicate that avian viruses of any subtype can contribute genes in the generation of reassortants. Virological surveillance revealed that influenza viruses in waterfowl reservoir are perpetuated year-by year in the frozen lake water while ducks are absent. PMID- 9360366 TI - [The virological, epidemiological and clinical features of influenza A, B and C viruses]. AB - Influenza epidemics that start abruptly and spread rapidly are caused by either influenza A or B virus. Although well-defined outbreaks of influenza C have rarely been reported, influenza C virus has been shown to cause a mild upper respiratory illness in children as well as in adults. Influenza A virus naturally infects several mammalian species including humans as well as a variety of avian species, whereas influenza B virus infects only humans. Influenza C virus primarily infects humans but has also been isolated from pigs. Furthermore, there are several differences in the biological and biochemical properties among three types of influenza virus. Here we summarize the virological, epidemiological and clinical features of influenza A, B and C viruses. PMID- 9360368 TI - [Prevention and control of influenza infection in the elderly in Japan--special emphasis on high risk group patients]. AB - These days, in the Japanese society the aged group which involve the high risk group patients has grown rapidly. In Japan, at present small epidemics of A Hong Kong (H3N2) and A Soviet (H1N1) influenza have occurred and influenza B has concurrent infection. However Asian type A (H2N2) virus disappeared since 1968. If Asian strain appeared again, most people of less than thirty years old with high risk group patients would have severe infection. We are afraid of the appearance of the new type A virus, because a great number of high risk group patients of aged people are there in Japan. Among the developed countries, vaccination against influenza in Japan is not satisfactory. Therefore mucosal immunity as well as humoral immunity in Japanese people will be worse compared with the people of the USA. We should establish the surveillance system for influenza in the adult and aged people in Japan and confirm the prevention and control procedures for the influenza epidemic new and in future. PMID- 9360369 TI - [Influenza virus genome structure and encoded proteins]. AB - Influenza A and B viruses each contain eight segments of ssRNA, and influenza C virus contains seven segments of ssRNA, with negative polarity. Each RNA segment encodes 1 or 2 proteins. The gene assignment for influenza A virus is as follows: RNA segment 1 codes for PB2, 2 for PB1, 3 for PA, 4 for HA, 5 for NP, 6 for NA, 7 for M1 and M2, and 8 for NS1 and NS2. M and NS genes of influenza A virus, NA, M, and NS genes of influenza B virus, and M and NS genes of influenza C virus encode two proteins. The terminal nucleotide sequences of individual RNA segments are the same within each type and also similar among different types, suggesting that A, B, and C viruses were derived from the same origin. Receptor recognition and receptor destroying proteins of A and B viruses, hemagglutinin(HA) and neuraminidase(NA), are similar in structure and character, but that of C virus, hemagglutinin-esterase(HE), is different. PMID- 9360371 TI - [Transcription and replication of influenza virus genome]. AB - The genome of influenza virus is composed of eight RNA segments of negative polarity. The RNA-dependent RNA polymerase is associated with each viral RNA (vRNA) segment and after infection, involved in both transcription (vRNA-directed synthesis of viral mRNA) and vRNA replication (vRNA-dependent synthesis of complementary RNA(cRNA) and cRNA-dependent synthesis of vRNA). The RNA polymerase is composed of three viral proteins, PB1, PB2 and PA. PB1 is the core subunit for not only the RNA synthesis but also the assembly of PB2 and PA into this multifunctional enzyme complex. PB1 alone is able to catalyze vRNA-dependent RNA synthesis, but PB2 is required for capped RNA-dependent transcription, both together forming the transcriptase. The third P protein, PA, and an as yet unidentified host factor(s) are involved for the conversion of RNA polymerase from transcriptase to replicase. The functional map including both subunit subunit contact sites and catalytic sites for capped RNA endonuclease and RNA polymerization is being made for both PB1 and PB2 proteins. PMID- 9360370 TI - [Functions of the segment-specific noncoding regions of influenza virus genome RNA]. AB - The genome of influenza A viruses consists of eight negative-strand RNA segments. These segments contain the untranslated regions (UTRs), ranging from 20 to 61 nucleotides, at their 3' and 5' ends. The UTRs are composed of the highly conserved terminal nucleotides and the segment-specific nonconserved nucleotides located adjacent the open reading frame of the viral RNAs. Utilizing the virus like model RNAs, whose nonconserved UTRs were mutated, deleted or replaced with those of other segments, the unique features of the nonconserved UTRs have been elucidated in the steps of transcription, translation, replication and RNA packaging into virus particles. Here I summarize current understanding of the functions of the segment-specific nonconserved UTRs of virus RNA. PMID- 9360372 TI - [Structure and function of the hemagglutinin of influenza viruses]. AB - The hemagglutinin(HA) of influenza virus is a major glycoprotein and plays a crucial role in the early stage of virus infection: HA is responsible for binding of the virus to cell surface receptors, and it mediates liberation of the viral genome into the cytoplasm through membrane fusion. The essential component of the receptor for influenza viruses has been considered to be the sialic acid. Influenza A and B viruses recognize N-acetylneuraminic acid, whereas influenza C virus specifically recognizes N-acetyl-9-O-acetylneuraminic acid as the receptor. Influenza A viruses are subdivided into 15 subtypes by their antigenic differences, but several amino acid residues composing functional domains (receptor binding site and fusion peptide) are shown to be conserved among HAs. PMID- 9360373 TI - [Structure and function of influenza virus neuraminidase]. AB - Crystallographic studies of neuraminidase and neuraminidase-sialic acid complexes enabled to design new potent antiviral drugs against influenza. In addition, recent advance in reverse genetics of influenza virus provides us a better understanding of interrelationship between structure and function of the neuraminidase. Progress in elucidating the relationship between structure and function will further contribute to the control of influenza. PMID- 9360374 TI - [The structure and function of the HE protein of influenza C virus]. AB - The hemagglutinin-esterase (HE) glycoprotein is an integral membrane protein and the major surface antigen of influenza C virion. It displays three biological activities: receptor-binding activity for N-acetyl-9-O-acetylneuraminic acid, fusion with the host cell membrane, and receptor-destroying activity which is a neuraminate-O-acetylesterase. This protein undergoes four kinds of posttranslational processing: proteolytic cleavage, N-glycosylation, fatty acid acylation, and phosphorylation. We summarize here the data concerning the sites on the HE molecule responsible for the biological activities including antigenic epitopes as well as those concerning the role of posttranslational modifications in virus replication. PMID- 9360375 TI - [Structure, function and regulation of expression of influenza virus matrix M1 protein]. AB - The M1 protein of influenza virus regulates the bi-directional transport of ribonucleoprotein (RNP) into and out of the nucleus. At the beginning of infection, the incoming RNP is transported into the nucleus only after detachment from M1, where RNP is involved in transcription/replication of the viral genome. In the late stage of infection, M1 inhibits viral RNA polymerase activity by binding to RNP, which may be a signal for RNP-transport from the nucleus to the cell surface. Finally, M1 mediates the association of RNP with viral envelope glycoproteins on the inner surface of the cytoplasmic membrane, which then promotes the virion formation and budding. Thus, M1 is a multi-functional protein that plays important roles in various steps of virus replication. PMID- 9360376 TI - [Structure and function of the influenza virus M2 ion channel protein]. AB - The M2 protein of influenza virus A is an integral membrane protein that is expressed on the infected cell surface and incorporated into virions. This protein is a minor component in virions but plays an essential role in the viral life cycle. The M2 protein, which forms a homotetramer, has H+ ion channel activity that is sensitive to an anti-influenza virus drug, amantadine, and is activated by low pH. When the virus enters cells, the M2 ion channel is activated in endosomes to acidify inside the virion, facilitating viral uncoating. The M2 channel also modifies the pH of the intracellular compartments to protect newly synthesized hemagglutinin from irrelevant low pH-induced conformational change for some influenza viruses. PMID- 9360377 TI - [Structure-function relationship of the influenza virus RNA polymerase subunits]. AB - Influenza virus RNA polymerase with the subunit structure PB1-PB2-PA is involved in both transcription and replication of the RNA genome. PB1 is the catalytic subunit and binds both to PB2 in its N-terminus and to PA in its C-terminus. PB2 is required for priming with cap and binds to PB1 in its N-terminus. PA is required for cRNA-->vRNA synthesis of genome replication and binds to PB1 in its C-terminus. Therefore, PB1 is the core subunit not only for RNA polymerase activity but also complex formation of the enzyme. Protease activity is identified in the N-terminal region of PA, but its role on viral proliferation remains unknown. PMID- 9360378 TI - [Structure and function of influenza virus nucleoprotein (NP)]. AB - Influenza virus nucleoprotein (NP) is the major structural protein which interacts with the 8 segment RNAs, to make the panhandle structure of RNPs, nucleocapsids, together with 3 polymerase protein complex (PB2, PB1, and PA). The NP proteins (498 aminoacids, MW 56,000) self-polymerize to form the panhandle structure similarly as the nucleocapsids. The nucleocapsids ensure the base pairing RNA structure in the handle region corresponding to the complementary structure in the both ends of vRNAs. This handle structure is supposed to play roles in regulation of switch for transcription and replication, and encapsidation. The NP protein is one of the type-specific antigens distinguishing among influenza A, B, and C type, and a target of cross-reactive CTL. PMID- 9360379 TI - [Structure and function of influenza virus NS1 and NS2 proteins]. AB - This review discusses the structure and function of the influenza virus NS1 and NS2 proteins. The NS1 is a phosphoprotein and has two nuclear localization signals. In the nucleus, the NS1 interferes with the splicing as well as the nuclear export of cellular mRNAs. In the later time of the infection, the NS1 is present in the cytoplasm and associates with the polysomes. The NS1 binds to the 5'UTR of some viral mRNAs and stimulates translation. The NS2 is a phosphoprotein and binds to the nucleoporin yRip1 and Rab/hRip as well as the M1 protein which associates with the vRNPs. Therefore, the NS2 protein plays an important role in the nuclear export of the vRNPs. Improved technique to genetically manipulate influenza virus allowed us to rescue NS1 and NS2 mutants which are useful for further study. PMID- 9360380 TI - [Mechanisms of antigenic variation in influenza virus]. AB - Human influenza A viruses evolve rapidly by antigenic shift and antigenic drift. Antigenic shift occurs by gentic reassortment between currently circulating human viruses and influenza viruses of other origin and by re-emergence of a previously circulating virus. The segmental structure of the virus genome enables reassortment in multiply infected cells and also promotes multiple infection because it results in yielding noninfectious particles which randomly lack some genome segment and only become infectious by complementation with others. Antigenic drift is due to an accumulation of nonsynonymous substitutions in the genes encoding the HA and NA proteins. The limited nature of infection to the respiratory epithelium which is the border of the immune system capacitates the virus to reinfect and grow under the partial immune pressure which results in selecting and expanding antigenic mutants. PMID- 9360381 TI - [Antigenic drift of type A and B influenza viruses]. AB - Epidemics of influenza of the past 10 years were reviewed by integrating records from Morbidity and Mortality Weekly Reports of the United States and Infectious Agents Surveillance Reports in Japan, as well as data of antigenic drift of epidemic strains. Nucleotide-sequencing analyses of field isolates have shown characteristic amino acid substitutions in their hemagglutinin molecules, and phylogenetic analyses have indicated evolutionary relationships among the viruses. Integration of information obtained from both epidemics and molecular analyses would help our understanding of antigenic drift and evolution of influenza viruses. PMID- 9360382 TI - [Evolutionary analysis of the hemagglutinin-esterase (HE) gene of influenza C virus]. AB - The phylogenetic tree constructed with the nucleotide sequences of the hemagglutinin-esterase (HE) genes of 25 influenza C strains isolated during the period from 1964 to 1988 revealed the existence of four discrete lineages. The evolutionary rate of HE gene was estimated to be 0.49 x 10(-3) substitutions per site per year. In the immunodominant region on HE protein, there was little or no amino acid sequence divergence among viruses on the same lineage, raising the possibility that immune selection may not have played a significant role in the evolution of HE after separation into lineages has occurred. The potential role of pigs in influenza C virus ecology remains to be clarified. Evidence was obtained, however, which suggests, that interspecies transmission of the virus between humans and pigs has occurred in nature. PMID- 9360383 TI - [The role of cleavage activation of the hemagglutinin by host and bacterial proteases in the induction of the pathogenesis of influenza viruses]. AB - Infectivity and pathogenicity of influenza viruses are based on the interplay between the viral glycoprotein hemagglutinin (HA) and appropriate host proteases. HA receives its full biological activities by proteolytic cleavage of a precursor molecule at a definite cleavage site. Tryptase Clara, an arginine-specific protease secreted by the Clara cells in the bronchial epithelia, is a principal host protease responsible for the cleavage activation and pathogenicity of influenza viruses. Although influenza in normal individuals is usually confined to the upper respiratory tract, the infection often develops into fatal pneumonia in patients with chronic lung diseases, where bacterial infections often occur. Synergistic effects of bacterial infections on the pathogenesis of influenza viruses are described in regard to the cleavage activation of HA. PMID- 9360384 TI - [Host range of influenza viruses and their receptor binding specificities]. AB - Host-range of influenza viruses are established by many factors in nature such as the quantitative, qualitative aspects of the viral receptor, the permissive and non permissive states of host-cell condition, and also the antibody and inhibitor pressure present in the host. Influenza virus hemagglutinin recognizes specific sialyl-sugar chains of the host cell membranes. In this paper, the structure and function of sialyl-sugar chains as influenza virus receptors are described in relation to the variation of influenza viruses and the molecular evolution of influenza virus hemagglutinin. PMID- 9360385 TI - [Active site for fusion activity of influenza virus hemagglutinin]. AB - A sequence of hydrophobic amino acids at the N-terminus of HA2 subunit of hemagglutinin (HA) is thought to be the active site for fusion activity, and called "fusion peptide". At neutral pH, fusion peptides are located inside the stem of HA spike. At pH 5, the heads of HA spike are dissociated and thereby fusion peptides are exposed and relocated probably at the top of newly formed long alpha-helix trimer. Fusogenic HA2 bridges two adjacent membranes by plunging fusion peptide into the target membrane. HA molecule is metastable at neutral pH. Oligosaccharides in the stem region, which are strictly conserved among various strains, maintain HA in the metastable form required for fusion activity. Cytoplasmic tail of HA also participates in fusion process. Addition of 5 amino acids at the end of cytoplasmic tail abolishes the fusion activity without affecting other biological properties of HA. PMID- 9360387 TI - [The receptor destroying enzyme of influenza viruses. The role of the receptor destroying enzyme on the budding and the release of influenza viruses from the host cells]. AB - Influenza viruses encode two envelope glycoproteins, neuraminidase(NA) and hemagglutinin (HA), for which high resolution crystal structures are available. HA mediates attachment of the virus to the host cells and fusion with the endosomal membrane. NA (EC 3.2.1.18; sialidase, acyl neuraminylhydrolase) catalyzes the removal of terminal sialic acid residues from viral and cellular glycoconjugates and is presumably responsible for the elution of progeny virus. NA also cleaves a terminal sialic acid from the cellular receptors, and thus is described as a receptor-destroying enzyme. In this paper, recent advances on the structure and function of the influenza virus neuraminidase are described. PMID- 9360386 TI - [The Mx protein that confers the resistance to influenza virus]. AB - The murine Mx1 protein was identified as an interferon-inducible host factor that confers the resistance to influenza virus. Mx proteins homologous to the murine Mx1 are subsequently found in a wide variety of species including human, rat, chicken, fish and so on. Mx proteins have the typical GTP-binding motif, and in fact, are shown to be GTP-binding proteins and GTPases. Nuclear Mx proteins selectively inhibit the primary transcription of orthomyxoviruses. In contrast, the cytoplasmic Mx protein, for instance, human MxA blocks the multiplication of not only orthomyxovirus but also rhabdovirus, paramyxovirus, and bunyavirus. Although the molecular mechanism by which Mx inhibits the virus multiplication is not completely clear, Mx may exert the antiviral activity possibly by the mechanism that VPS1p or dynamin, members of the Mx family, is involved in the intracellular protein translocation. PMID- 9360388 TI - [Mechanism of the induction of apoptosis by influenza virus infection]. AB - Influenza virus-infected HeLa cells show phosphatidylserine externalization, chromatin condensation, increase of membrane permeability, and inactivation of a mitochondrial enzyme(s), which are collectively referred as apoptosis. The amount of cell surface Fas and its ligand increases before the onset of apoptosis and the presence of a Fas-ligand-antagonizing antibody inhibits apoptosis. Since virus-infected cells simultaneously express Fas and Fas-ligand, it is likely that apoptosis is induced when the cells come into contact with each other. We expect that apoptotic death of influenza virus-infected cells contributes to elimination of the virus from host organism. PMID- 9360389 TI - [Antigenic epitopes of influenza virus specific CTL]. AB - CTLs play an essential role in the protection to influenza virus infection. Virus specific CTLs recognize the complex of class I molecule and epitope peptide derived from viral proteins on surfaces of virus infected cells. In these 10 years great progress has been made in understanding of the process of epitope peptide production and the structure of the peptide. It has been clearly shown that proteasome and TAP are involved in the class I restricted antigen processing and epitope peptides have motifs depending on class I allele. In this article topics concerning CTL epitopes of influenza viruses are described; especially prediction and identification of epitopes are mainly discussed. PMID- 9360390 TI - [Deleterious pathogenic mechanism involving host response in influenza virus infection in mice]. AB - In the influenza virus infected mice there is a host response which involves free radical generation particularly in the host lung. First, superoxide generation was elevated excessive extent, 200-600 fold in the alveolar lavage fluid (BALF), by induction of xanthine oxidase which becomes maximal at about 8 days after infection while virus yield becomes maximum on day 4. Mice start to die on day 9 although the virus in BALF is undetectable; thus virus disease in the absence of virus. Second, inducible form of nitric oxide synthetase is also triggered exactly in parallel to xanthine oxidase. This indicates NO and O2- is produced simultaneously implicating the formation of peroxynitrite (ONOO-) due to a rapid reaction between NO + O2-. Consequently nitration of lung tissue by ONOO- was demonstrated. ONOO- is also found much toxic than O2- or H2O2 in the cultured cells. Third, proteases are involved in various ways in this infection; activation of xanthine dehydrogenose to xanthine oxidase, activation of viral infectivity and triggering of bradykinin generation and inflammation by activating prekallikrein. Lastly, activation of matrix procollagenase (proMMP) by ONOO- and NO2, generated above, was suggested, which will damage connective tissue. Thus all events involving proteases will augment viral pathogenesis. PMID- 9360391 TI - [Mortality associated with influenza epidemics in Japan--analysis for viral type, age and risk groups]. AB - In this report, mortality with influenza in Japan was analyzed. The data covered mainly the period 1975-94. I tried to analyze these data for cause of death, viral types, age groups and three categories of diseases in order to determine distinctive risk factors for influenza-associated mortality. To summarize, influenza is a common disease which could lead especially for the elderly and those who have increased risk factors (cardiovascular diseases, cerebrovascular diseases and pulmonary complications) to severe complications and death. The cause of death is thought to be mainly influenza related pneumonia. Elderly and high-risk persons should be vaccinated. PMID- 9360392 TI - [Comparative features of pneumonia associated with influenza]. AB - Three manifestations of pneumonia that are associated with influenza are well recognized: primary influenza viral pneumonia, secondary bacterial pneumonia and mixed viral and bacterial pneumonias. In an outbreak of influenza, primary influenza viral pneumonia has occurred predominantly. After a typical onset of influenza, there is a rapid progression of fever, cough and dyspnea. Physical examination and chest roentgenography reveal bilateral findings but no consolidation. A Gram stain of the sputum fails to reveal significant bacteria, and bacterial culture yield sparse growth of normal flora, where as viral cultures yield high titers of influenza virus. Such patients do not respond to antibiotics. Secondary bacterial pneumonia often produces a syndrome that is clinically distinguishable from that of primary viral pneumonia. Recrudescence of fever is associated with symptoms and signs of bacterial pneumonia such as cough, sputum production, and an area of consolidation detected on physical examination and chest roentgenography. Gram staining and the culture of sputum reveals a predominance of a bacterial pathogen, most often H. influenzae, S. pneumoniae, B. catarrhalis, or S. aureus. Such patients usually respond to specific antibiotic therapy. During an outbreak of influenza many cases an observed that do not clearly fit into either of the aforementioned categories. The disease is not relentlessly progressive, and yet the fever pattern may not be biphasic. These patients may have primary viral, secondary bacterial, or mixed viral and bacterial infection of the lung. PMID- 9360393 TI - [Neurovirulence of influenza virus in mice]. AB - Neurovirulence in mice is a unique property of some influenza virus strains including NWS and WSN strains. We performed clinical and immunohistochemical studies on mice after intracerebral inoculation with the neurovirulent WSN. On day 3 after inoculation, WSN antigen was detected in meningel and ependymal areas, neurons of circumventricular regions, the cerebral cortices, the substantia nigria zona compacta and the vental tegmental area. On day 7, advanced accumulation of the viral antigen was evident in the substantia nigra zona compacta and hippocampus. Double immunostaining demonstrated that the WSN antigen was only seen in neurons and not in microglia or reactive astrocytes. The responsible genes for neuro virulence were summarized. PMID- 9360394 TI - [Acute encephalitis and encephalopathy at the height of influenza in childhood]. AB - Twenty six infants and children with acute encephalitis and encephalopathy during two influenza seasons in Hokkaido, the northernmost island of Japan, were reported. Thirteen patients died and 5 had residual neurological sequelae. Influenza virus genome was detected by PCR in 9 out of 10 cerebrospinal fluid samples from these patients. CT and MRI of the brain demonstrated symmetrical changes in the thalamus and brainstem. The prevalence of these encephalitis and encephalopathy of childhood should be surveyed by nationwide scale. PMID- 9360395 TI - [Clinicopathological features of influenza myocarditis and pericarditis]. AB - Myocarditis is a rare complication of influenza infection but is occasionally fatal. Recent application of percutaneous cardiopulmonary support and/or intraaortic balloon pumping to the serious case of viral myocarditis brought an good prognosis. We should recognize that the patient with viral infection such as influenza may have myocarditis and should make an early diagnosis for adequate treatment in time. To avoid misdiagnosis we must know characteristic symptoms and signs of cardiac involvement during influenza infection. PMID- 9360396 TI - [Viremia in influenza: detection by polymerase chain reaction]. AB - Gastroenteritis, arthralgia and myalgia are frequently associated with influenza virus infections in humans. One explanation for these symptoms may be that they are due to extra respiratory transmission of virus by viremia. We tried to detect genomic viral RNA of the nucleoprotein (NP) and H3 subtype hemagglutinin (HA) genes by method of RT-PCR in peripheral blood mononuclear cells (PBMC) of 18 children aged 1-14 who suffered from an influenza outbreak in the Kansai district of Japan between December 1992 and February 1993. Three of the 18 samples were RT PCR positive. The NP gene sequence observed in one patient's PBMC was identical to that obtained from his throat swab fluid. The HA gene sequences observed in the two other PBMC differed from those of RT-PCR amplified DNA from throat swabs by an order of 3-9 nucleotides. Moreover we tried to isolate virus by co-culture with MDCK cells and RBC or WBC of the patients from an influenza outbreak between December 1993 and March 1994. No virus was isolated from 9 patients suffering from H3 subtype but virus was isolated from 5 of 17 patients suffering from type B influenza virus. We believe these results suggest that the viremia on influenza infection is not so rare. PMID- 9360397 TI - [Protective antigen of influenza virus]. AB - Influenza A virus is unique among human viruses in its capacity to alter the antigenic phenotype with relative ease and evade neutralizing antibodies. This property is ascribed to the accumulation of a series of amino acid changes in the antigenic regions of hemagglutinin (HA) molecule. Neutralizing antibodies against HA prevent the early stage of infection, whereas neuraminidase (NA) antibodies mediate the antiviral effect by restricting spread of viruses in the host cells after infection. Thus the understanding of antigenic structure on those protective antigen is significant. Sequence analysis of natural variants and escape mutants selected by monoclonal antibodies allowed us to assign each antigenic sites and epitopes to a particular region on the three dimensional structure of HA and NA molecules. PMID- 9360398 TI - [Mucosal immune responses against influenza virus]. AB - The respiratory tract-mucosa is the site of either contact with influenza virus or defense against the virus. Such a defense is mediated by immune competent cells. The precursors of IgA-producing B cells and immune T cells are first induced in the mucosal inductive sites such as nasal-associated lymphoid tissues (NALT) or bronchus-associated lymphoid tissues (BALT). They are disseminated to mucosal effector sites for the development of immune responses, where IgA producing cells in the lamina propria produce polymeric IgA, which are secreted through the epithelial cell into the external. The secretory IgA and serum IgG are mainly involved in protection against influenza in the upper respiratory tract and pneumonia in the lower respiratory tract, respectively. CD8+ cytotoxic T cells and Th1 cells are involved in recovery from influenza. PMID- 9360399 TI - [Inactivated influenza virus vaccine: the status quo and several new approaches for future application]. AB - Inactivated influenza vaccines were first developed in the 1930s and then, more efficient methods of virus purification and disruption have led to less toxic vaccine, e.g. HA-split vaccine. A program of annual immunization to schoolchildren had been recommended in Japan since 1960. This assumed that the high incidence of influenza morbidity among schoolchildren might play a role in extending influenza in general population. However, due to the lack of detailed data, the public had bee reluctant to accept, especially for healthy children. Accordingly, the Japanese government changed its policy to vaccinate on demand, which resulted in a marked decrease of vaccinees. Several alternative approaches are in progress to produce more efficient vaccines. DNA vaccine, plasmid DNA encoding influenza peptides, seems promising for future application. However, as it will take more years for clinical evaluation, it is urgent to design a protocol to estimate cost-effectiveness of the presently available inactivated vaccine. PMID- 9360400 TI - [Intranasal application of inactivated influenza virus vaccines]. AB - Recent concept on the common mucosal immune system gives new direction of influenza vaccine development-mucosal vaccine. Vaccines have to be administered over the mucosal surface (in case of influenza vaccine, intranasal route may be the most suited route) to assure mucosal immunity which is the first hand armament against influenza virus. This article reviews our work on intranasal administration of inactivated influenza virus HA vaccines. Since influenza vaccines are usually given to people who has some degree of immunity due to past infection or immunization, vaccines which have booster effect are preferable. In this context, intranasally administered inactivated influenza HA vaccine was more immunogenic than cold adapted reassortant live influenza virus vaccine, another candidate mucosal influenza virus vaccine, which is now under investigation in the United States. PMID- 9360401 TI - [Recent progress in live influenza vaccine development]. AB - As live influenza vaccine, cold-adapted influenza virus vaccines (ca vaccine) have been extensively investigated in both the U.S and Russia. In Russia it has been licensed since 1988 and it is going to be licensed in the U.S. within a year or two. In general, the ca vaccine is more effective in seronegative population than the inactivated vaccine. In seropositive adult population, both are equally effective. In the elderly, inactivated vaccine is better than the live vaccine. In Japan, clinical trials were also conducted with the American ca vaccines. Although the efficacy was confirmed in limited locations, the vaccine could not be evaluated from the point of license approval because big epidemic did not occur during the studies. PMID- 9360402 TI - [Efficacy and adverse reactions of influenza vaccine in the elderly]. AB - Influenza virus infection is a serious problem in the elderly because of the high pneumonia complication rate and a significant increase in mortality. Influenza vaccine is a method for controlling influenza epidemics in the elderly. The vaccinated elderly showed lower influenza infection rate and had fewer incidences of febrile episodes than did non-vaccinees during epidemics. Significantly, decreased rates of mortality subsequent to influenza epidemics among vaccinated elderly inpatients were also found. The antibody response to influenza vaccine in the elderly is quite comparable to that of younger adults. Adverse reactions to influenza vaccination, including local reaction such as soreness, systemic reactions such as malaise and fever, and allergic reactions, are less frequent in the elderly than in children and younger adults. The currently used inactivated influenza virus vaccine is as safe or safer than other vaccines. Serious adverse effects are unknown in the elderly. The influenza vaccination rate is quite low in Japan when compared with that of other developed countries. To prevent influenza epidemics among the elderly, especially among those who have been institutionalized, influenza vaccine should be promoted more actively. PMID- 9360403 TI - [Current status of research and development for anti-influenza virus drugs- chemotherapy for influenza]. AB - Antiviral research for influenza viruses (FluV) is proceeding actively whereas few compounds are available for clinical use. Amantadine, an inhibitor of M2 ion channel of FluV-A has been a key compound which disclosed important function of M2 protein, however, its clinical efficacy is restricted only in chemoprophylaxis of infection. Recently several compounds which showed novel antiviral mechanism for FluV replication emerged. They are inhibitors of conformation change of HA, of fusion of envelope and cellular membrane, of endonuclease on mRNA, of viral RNA replication, and of NA activity. Although most of these inhibitors are under investigations some of them are in clinical trial of phase II or phase III. It is obvious that most important problem in clinical use of anti-FluV drugs should be its side effects, bioavailability and stability in human bodies. PMID- 9360404 TI - [Antisense nucleic acid therapy of influenza virus]. AB - We have demonstrated that Antisense phosphodiester (ODNs) and phosphorothioate oligonucleotides (S-ODNs) inhibit CAT (chloramphenicol acetyltransferase) protein expression in the clone 76 cell line, which is a derivative of the murine C127 cell line. This cell line expresses the influenza virus RNA polymerase and nucleoprotein (NP) genes in response to treatment with dexamethasone. Phosphodiester, phosphorothioate, and liposomally encapsulated oligonucleotides with four target sites (PB1, PB2, PA, and NP) were synthesized and tested for inhibitory effects by a CAT-ELISA assay using the clone 76 cell line. The liposomally encapsulated ODNs and S-ODNs complementary to the sites of the PB2 AUG and PA-AUG initiation codons showed highly inhibitory effects. On the other hand, the inhibitory effect of the S-ODNs targeted to PB1 was considerably decreased in comparison with the other three target sites. Liposome encapsulation afforded oligomer protection in serum-containing medium and substantially improved cellular accumulation. The liposomally encapsulated oligonucleotides exhibited higher inhibitory activity than the free oligonucleotides. Liposomal preparations of oligonucleotides facilitate release from endocytic vesicles, and thus, cytoplasmic and nuclear localization are observed following cell treatment. The activities of the unmodified oligonucleotides are effectively enhanced by using the liposomal carrier. In the observation of the endocapsulated antisense phosphodiester oligonucleotide, FITC-ODN-PB2-as treated clone 76 cells by a confocal laser scanning microscope, diffuse fluorescence was apparently observed in the cytoplasm. Interestingly, the endocapsulated antisense phosphorothioate oligonucleotide, FITC-S-ODN-PB2-as accumulated in the nuclear region of clone 76 cells. However, weak fluorescence was observed on the endosomes and in the cytoplasmes of the free antisense phosphorothioate oligonucleotides treated clone 76 cells. PMID- 9360405 TI - [Research on development of hybrid artificial liver utilizing reconstituted extracellular matrix]. AB - We investigated culture of adult rat hepatocytes on reconstituted extracellular matrix, glycosaminoglycans containing collagen gel and on a porous gelatin sponge (gelform) for the maintenance of the liver-specific functions of hepatocytes. In the culture on reconstituted extracellular matrix, only heparin containing collagen cultures could significantly sustain albumin synthesis for over 3 weeks. On the other hand, in the culture of rat hepatocytes on a porous gelatin sponge, the morphology of the hepatocytes immobilized on the support was close to that in vivo and the secretion of albumin and bile acids was stable for over 12 days. These results demonstrate that culture on two- and three-dimensional culture with reconstituted extracellular matrix is one of the promising hepatocytes cultures for development of artificial liver. PMID- 9360406 TI - [Development of new cell fusion technique by laser device and application to bio medical field]. AB - We developed a new cell fusion method which was sterile, noncontact, and selective technique under the microscope, using the micro-processing device by LASER. By this technique, we succeeded in fusing myeloma cell (SP2) and lymphocyte in mouse. We also defined the proliferation of the fused cells in HAT medium and the function of the fused cells in the Ouchterlony method, i.e. production of IgG. This method enable us to make hybridomas from very small number of cells and to fuse target cells selectively. This method is applicable to fuse cells which are difficult to be fused by conventional methods. PMID- 9360407 TI - Towards guidelines for withdrawal of care in comatose survivors of cardiac arrest. PMID- 9360408 TI - When to stop treatment in comatose patients after successful cardiopulmonary resuscitation? A practical approach. PMID- 9360409 TI - Insulin and leptin concentrations in obese humans during long-term weight loss. AB - BACKGROUND: Leptin is likely to be involved in the homeostasis of body weight. Insulin is suggested to regulate both short-term and long-term circulating leptin levels. The present study aims to assess the relation between insulin and leptin levels in obese humans. METHODS: Some 53 obese subjects (body mass index 35.1 +/- 3.9 kg m-2 (mean +/- SD)) were prescribed a hypocaloric diet and randomized to either a placebo or the intestinal lipase inhibitor orlistat for 2 years. Serum leptin and insulin levels were determined repeatedly during these 2 years (5 times in the fasting condition and twice after an oral glucose load). RESULTS: Leptin concentrations appeared to be regulated at a specific level for each individual throughout the weight-loss period. The BMI explained 39.7% of the total variance in leptin levels, the body-fat distribution 17.2%, individual characteristics 30.3%; and the fasting serum insulin concentration 1.0%. After a mean weight loss of 7.7 +/- 4.9 kg, the time-integrated insulin response to an oral glucose load was significantly lower but the leptin response remained unchanged. CONCLUSIONS: The BMI is the main determinant of the circulating leptin concentration in obese humans. Individual characteristics seem to determine the leptin level, given the BMI. In a short-term observational study in obese humans, changes of insulin levels do not appear to be correlated to changes in leptin levels. PMID- 9360410 TI - HIV-related thrombotic thrombocytopenic purpura: report of 2 cases and a review of the literature. AB - Thrombotic thrombocytopenic purpura (TTP) is a syndrome characterised by the clinical pentad of microangiopathic haemolytic anaemia (MAHA), thrombocytopenia, renal failure, fluctuating neurologic signs, and fever. The aetiology of TTP is unknown, but associations with various underlying diseases, infections and drugs have been identified. One of these associations is with HIV infection. We describe the clinical picture, the laboratory results and the response to plasma therapy of two cases of HIV-associated TTP. In both patients, a longitudinal semiquantitative assessment of the numbers of schistocytes in blood was made, which correlated well with the more traditional parameters of disease activity. Since 1987, at least 49 patients with HIV-associated TTP have been reported. A case-analysis of the 38 patients who were described in sufficient detail and a review of the literature in the setting of HIV infection is presented. The most important conclusions from these combined data are: (1) TTP usually seems to occur in patients with a CD4+ lymphocyte count < 250 x 10(6).l(-1); (2) more than 50% of the patients present with TTP soon after or during an infectious or malignant disease; (3) plasma exchange is the therapy of choice, still resulting in mortality of 22%; (4) higher initial platelet count and creatinine level are correlated with an adverse outcome. PMID- 9360411 TI - Fever attributed to the use of hydroxyurea. AB - We report on three patients who developed fever after starting treatment with the anti-neoplastic agent, hydroxyurea. Fever occurred within 5 days to 3 weeks after starting treatment. In all cases the causal relationship between fever and use of hydroxyurea was demonstrated by spontaneous recovery after drug withdrawal and was confirmed by recurrence of fever after rechallenge. Other causes were excluded. Fever was accompanied by rash, gastro-intestinal and pulmonary symptoms, and arthralgia. Physicians should be aware of the fact that unexplained fever may be caused by hydroxyurea. PMID- 9360412 TI - Fever caused by hydroxyurea: a report of three cases and review of the literature. AB - Hydroxyurea (HU) is generally regarded as an effective and well-tolerated drug for the treatment of the chronic myeloproliferative syndromes. It has rarely been implicated as a cause of drug fever. We report two patients with primary thrombocythaemia and one patient with polycythaemia vera who developed fever and shaking chills during treatment with HU. Infection was highly suspected and all patients were examined extensively. The fever subsided after discontinuation of therapy with this drug. However, the fever recurred within 1 day after rechallenge. The mechanism of HU-induced fever remained unclear, but the experience in our patients and the reviewed cases in the literature are highly suggestive of a hypersensitivity reaction. Clinicians should be aware of this rare adverse effect. PMID- 9360413 TI - Be aware of abdominal tuberculosis. AB - Abdominal tuberculosis is often diagnosed in a late stage because symptoms are aspecific. Two patients with intestinal tuberculosis and tuberculous peritonitis respectively, both from endemic countries presented with long-standing fever, abdominal pain and weight loss. Acid fast bacilli were present in aspirate and biopsy specimens obtained by colonoscopy and laparoscopy respectively; PCR was positive for M. tuberculosis complex and later M. tuberculosis was cultured. Both patients responded to antituberculous therapy. In one patient AIDS was diagnosed. PMID- 9360414 TI - Detection of HIV p24 from antigen presenting monocytes for early diagnosis of HIV 1 infection. AB - The monocytic/macrophagic lineage has an antigen presenting cell function also towards HIV. On the basis of this fact, a new method, indirect immunofluorescence (IIF) for measurement of p24 from monocytes was used. The results were compared to an amplified enzymatic test for serum dissociated p24 detection in 14 HIV negative individuals at risk for HIV and 12 HIV positive patients. Only one seronegative, who had a symptomatic primary HIV infection, had a positive IIF and also an elevated level of p24 in serum. The others had a negative IIF and, 6 months after the specimen, were not positive to the routine methods for detection of anti-HIV antibodies. Seronegative subjects not at risk for HIV were consistently negative to IIF. Among the HIV positive patients 4 were positive to IIF and the remaining 5 were positive to routine methods. Divergent results could be explained by the fact that one test measures cell derived antigen and the other serum antigen and that monocytes can loose APC function in the advanced stages of the illness. The test proved to be cheap and simple, and it is possible to hypothesize an application of it as a support test for the early diagnosis of HIV infection in laboratories not endowed with high levels of technology. Moreover, the results of the amplified p24 ELISA test in 44 seronegative at risk test are reported herein. PMID- 9360415 TI - Oxidative stress status in children with nephrotic syndrome. AB - In continuation of our work on human stress situation and present day awareness of the role of free radical toxicity in a variety of clinical conditions, oxidative stress status (in terms of serum levels of MDA, scavenging enzyme SOD, vitamins: C and E) has been studied in 45 pediatric patients with nephrotic syndrome (further classified as steroid: responders, frequent/ infrequent relapsers, dependents). The results have been compared with 42 appropriately age healthy children as controls. The salient features of the present study centre around typical observations viz significantly increased levels of MDA (7.92 +/- 2.24 nmol/ml), decreased levels of SOD (1.36 +/- 1.01 U/ml), vitamin C (0.49 +/- 0.17 mg/dl) and vitamin E (0.52 +/- 0.19 mg/dl) in children with nephrotic syndrome as a whole when compared with healthy controls [MDA (4.40 +/- 1.31 nmol/ml), SOD (3.04 +/- 1.83 U/ml), vitamin C (0.60 +/- 0.26 mg/dl) and vitamin E (0.68 +/- 0.25 mg/dl) respectively]. An almost similar trend was encountered in different groups as classified. However, maximum fluctuations were observed in steroid dependents. The present observations appear to be suggestive of alternative guidelines to clinicians in the absence of conventional renal biopsy as the procedure. It is felt that children with nephrotic syndrome should regularly take vitamins C and E from the health point of view. PMID- 9360416 TI - Studies on the oxygen transport in the clinical association between Hb-S and Hb C. AB - The whole blood oxygen affinity of a Negro carrier of SC disease was found to be characterized by some right-shifted p50 and clearly increased Bohr effect, whereas the isolated and purified Hb-S and Hb-C exhibited slight deficiencies mainly of the Bohr effect. The right-shifted p50 from whole blood can be easily explained by the mild anemia with a parallel increase of 2,3-diphosphoglycerate (DPG), whereas the functional discrepancies between whole blood function and that of the purified Hb-S and C could be due, at least in part, to the presence in vivo of consistent amounts of hybrid Hb tetramers of the type alpha alpha beta S beta C. Unfortunately, the mechanism promoting the formation (or dissolution) of hybrids are fundamentally unknown; so, either their presence and functional properties are very difficult to be explored. PMID- 9360417 TI - Prognostic value of desmoplastic reaction and lymphocytic infiltration in the management of breast cancer. AB - OBJECTIVE: To ascertain whether the prognostic value of desmoplastic reaction and lymphocytic infiltration are a good prognostic index to estimate survival in breast cancer patients. METHODS: From 1987 to 1994, the authors have evaluated the prognostic value of desmoplastic reaction and lymphocytic infiltration related to rode state in 34 patients with breast cancer. For statistical analysis and comparison of means the "t"-test was used. The significance level was 0.01. RESULTS: The group of patients with abundant desmoplastic reaction shows an overall survival rate lower than the group with poor desmoplastic reaction (p < 0.01) and the survival of the group with abundant desmoplastic reaction was related to lymphnodal status. CONCLUSIONS: Many prognostic factors have been shown during these years, some connected to patient, some connected to neoplasm and others connected to the treatment. Recently many other prognostic factors have been recognized, among which the possible prognostic role of desmoplasia has been carefully valued. Certainly, today the prognostic value of desmoplastic reaction and lymphocytic infiltration cannot take the place of usual prognostic factors in the evaluation of breast cancer patient yet the desmoplastic reaction is a good prognostic index to estimate the survival in these patients. PMID- 9360418 TI - Ultrasound diagnostic criteria in breast disease. AB - The Kasumi-Kamio parameters (margins, peripheral echoes, internal echoes, posterior echoes, lateral shadow cones) and the ratio between the longitudinal and transverse diameter of the breast lump form the basis for a list of standardised diagnostic criteria on which to base an analysis of breast disease that assesses the specificity and sensitivity of ultrasonography as a valid, reliable initial step in the diagnosis of breast tumours. The study was based on a series of 129 tumour cases and produced correct diagnosis in 89.28% of benign, 83.33% of malignant cases. PMID- 9360419 TI - Diurnal rhythm of serum erythropoietin circulating levels in chronic obstructive pulmonary disease. AB - OBJECTIVE: Since erythropoietin (Epo) presents a diurnal rhythm in its circulating serum levels and it is reported increased in patients with chronic obstructive pulmonary disease (COPD), the circadian rhythm of Epo was investigated in a group of 40 normocytemic patients with chronic obstructive pulmonary disease compared with 40 clinically healthy subjects. METHODS: Venous blood samples were drawn in each subject during the span of a whole day every four hours, starting from midnight, for the determination of serum Epo levels by RIA. Statistical analysis was carried out by chronograms and by means of the "cosinor" method. RESULTS: The control group presents a significant (p < 0.001) circadian rhythm in serum Epo levels, with maximum in the afternoon, whereas no rhythm (p > 0.05) is detected in the patient group. This has significantly (p < 0.05) higher mean daily levels and lower diurnal variations of serum Epo than the control group; a significant (p < 0.05) difference exists between the two groups regarding the peaks of rhythms. CONCLUSION: These data confirm the presence of circadian rhythm in serum Epo levels and suggest that the COPD, by daytime hypoxemia with associated severe nocturnal desaturation, is associated with increased serum Epo levels both by day and by night, so that the physiological circadian rhythm is lost in these patients. PMID- 9360420 TI - Intraerythrocytic 2,3-diphosphoglycerate concentration in hypertensive subjects before and following control by anti hypertensive treatment. AB - METHODS: We measured the 2,3-diphosphoglycerate inraerythrocytic concentration in 24 normal controls and in 24 hypertensives before and following drug therapy. RESULTS: In hypertensives the 2,3-diphosphoglycerate concentration was higher than that of the controls (14.96 mumol/g Hb vs 13.26 mumol/g Hb respectively); the difference is statistically significant (p < 0.001). Following control of the hypertension by drug therapy, the 2,3 DPG levels in the patients studied do not seem to differ statistically from those of the controls. CONCLUSIONS: This may be a consequence of lower cardiac output in hypertension which results to a lower tissue perfusion, leading to an increased concentration of deoxygenated haemoglobin in the vein blood. Measurement of 2,3-diphosphoglucerate may prove of value in estimating tissue perfusion in hypertension. PMID- 9360421 TI - Spatiotemporal stationarity of epileptic focal activity evaluated by analyzing magnetoencephalographic (MEG) data and the theoretical implications. AB - BACKGROUND: The emitted brain neuromagnetic activity was recorded from patients suffering from idiopathic epilepsy, using a Superconductive Quantum Interference Device (SQUID). This activity will be referred as magnetoencephalogram (MEG). METHODS: The MEG recording which were obtained from 32 equal spaced points of a rectangular 4 x 8 matrix were analysed using Fourier statistical analysis. Then, a two dimensional brain mapping technique was utilized in order to detect the possible existence and the accurate localization of epileptic foci. The applied technique was based on the construction of ISO contour maps which are lines of equal power spectral amplitudes of the scalp spatial distribution of the recorded MEGs specific frequency bands. These maps will be referred as ISO-SA maps. A number of more than 200 epileptic patients were examined using this method. For each patient the magnetic brain activity was recorded for the temporal lobes, the frontal lobe and the occipital lobe. ISO-SA mappings were reconstructed for the frequency bands of the compound delta and theta rhythms (2-7 Hz), the alpha rhythm (8-13 Hz), and the beta rhythm (14-25 Hz). In these mappings epileptic (pathological) foci are represented as points emitting abnormal high magnetic power in the frequency band of 2-7 Hz. RESULTS: Systematic MEG measurements showed that the abnormal activity of a certain cortex region, when present, is stationary, i.e., time-invariant. CONCLUSIONS: Brain magnetic fields on the order of magnitude a picotesia are considered as to their possible physiologic nature, and a query is made as to what physical mechanisms might be involved in this propitiation. PMID- 9360422 TI - Haemostatic effects of iloprost in patients with lower limb ischemia. AB - The aim of this study was to investigate the haemostatic effects of iloprost, a stable analogue of prostacyclin, in patients with peripheral arterial disease. In a group of 13 patients with obliterative arteriopathies of the lower limbs the plasma levels of thrombomodulin (TM), betathromboglobulin (beta-TG), D-dimer (DD) and plasminogen activator-inhibitor (pAI-1) were measured, and compared to the values obtained from 10 healthy volunteers. All the parameters were found to be significantly higher in vasculopathic patients. These haemostatic evaluations were carried out after 4 weeks of treatment with iloprost up to 2 ng/kg/min, 6 hours infusion per day. During and at the end of treatment a clinical improvement was recorded. The patients also showed a significant decrease in plasma beta-TG and DD at the end of treatment. These data suggest that iloprost exerts clinical improvement, in who may have a part the decrease of platelet activation and of fibrin turnover. PMID- 9360424 TI - Geographical incidence of infection with Borrelia burgdorferi in Europe. AB - During recent years many seroepidemiological studies have been published about Lyme borreliosis in various European countries. This paper presents a review of these studies to clarify the geographical incidence of the infection by B. burgdorferi in Europe and particularly in Italy. Data of Lyme disease seroprevalence has been established in European patients or at-risk populations and in blood donors or control subjects. In Northern Europe the sero-prevalence of antibodies to B. burgdorferi in patients or in at-risk subjects is higher in Sweden, 19% and lower in Estonia, 2.7%. In Central Europe the incidence of antibodies to B. burgdorferi in patients or in at-risk subjects is higher in The Netherlands, 28% and Switzerland, about 26%, and lower in Poland, 15%. The range of antibodies to B. burgdorferi in blood donors or control subjects shows the highest spikes in Ireland 15% and the lowest in Austria 7.7% and in Germany 5.5%. In Southern Europe we have the highest incidence in Croatia, 43%, while we have the lowest incidence in Greece, 1.1%. In Italy the seroprevalence of antibodies to B. burgdorferi in patients or in at-risk subjects seems to vary, in Northern Italy, from the lowest incidence in Lombardia 3.2% to the highest in Friuli 22.3%; in Central Italy, from the lowest incidence in Emilia (Parma) 0.2% to the highest in Toscana 18.3%. The range of antibodies to B. burgdorferi in blood donors or control subjects shows the lowest spikes in Lazio 1.5%, while the highest are in Sicilia 10.9%. Although the amount of works on infection diffusion by B. burgdorferi is increasing, the statistical evaluations, comparisons and the drawing of acceptable conclusions continue to be difficult. In fact data, obtained from various European laboratories, are often not directly comparable, because of different serological tests used to detect antibodies to B. burgdorferi. Consequently it seems very important the work that could be performed by a multicenter study on the standardization of the criteria to be used in WB interpretation, presently in progress among several different European laboratories, and the necessary consequent efforts to elaborate a common panel of criteria about the comparison of the data. PMID- 9360423 TI - Thalassemia and G6PD deficiency in Spanish blood donors. AB - Our purpose was to determine the frequency of the thalassemia trait and glucose-6 phosphate dehydrogenase (G6PD) deficiency in blood donors of Madrid, composed of persons from nearly all the Spanish provinces (ranging from 21 to 65 years of age). The frequency of thalassemia and G6PD deficiency has been investigated with the following results; thalassemia 0.92% and no G6PD deficiency. The frequencies observed are compared with those found in the general (non donor) Spanish population. The value of this experiment is considered a supplement to other tests done routinely in our official blood donors. PMID- 9360425 TI - Atypical neuroleptics in the treatment of early onset schizophrenia. AB - The most complex problems in the use of neuroleptics for schizophrenia are the frequency of nonresponders, the severity of extrapyramidal side effects and tardive dyskinesia, especially in chronic treatment, the persistence of treatment refractory symptoms, such as negative symptoms. All these problems are more frequent and severe in children and adolescents with early-onset schizophrenia. The classic neuroleptics act on the postsynaptic dopaminergic receptors, especially the D2 receptors, situated in various areas of the Central Nervous System. More recently, the so-called dopaminergic hypothesis of schizophrenia has been criticized and other neurotransmitter systems have been involved, particularly serotonin. The more recently synthesized neuroleptics, with combined action on dopamine and serotonin receptors, have been called atypical neuroleptics; the atypical neuroleptics currently used in clinical practice are clozapine and risperidone. These anti-psychotic drugs are known to be clinically more effective, especially on negative symptoms, have a lower incidence of extrapyramidal side effects, produce significant improvements in some refractory patients. A large number of the studies concern adults; the studies on young populations are much fewer and less rigorous. The aim of this critical review is to describe clinical use of atypical neuroleptics clozapine and risperidone in children and adolescents with early-onset schizophrenia. PMID- 9360426 TI - Bypass grafting for a right proximal subclavian artery pseudoaneurysm patient using a long temporary bypass. AB - We report an 80-year-old woman, with pseudoaneurysm of the right proximal subclavian artery despite the absence of a history of trauma. On preoperative examinations, the aneurysm involved to the common carotid arteries. A long temporary bypass using a heparin-coated tube from the right femoral artery to the right common carotid artery was created under low dose systemic heparinization. A Dacron bifurcation graft bypassing was then performed successfully. At surgery for right proximal subclavian artery aneurysm, which often involves the right common carotid artery, intraoperative accident or bleeding can induce brain ischemia. A temporary bypass should be prepared. Although the short temporary bypass from the aorta to the right common carotid artery was reported, this carries the risk of complications due to microemboli. The heparin-coated tube provided excellent anti-thrombosis. Inflow cannulation should be placed at the peripheral artery not the aorta. PMID- 9360427 TI - Delayed chest wall pain after coronary artery bypass. AB - The author describes a patient who has a successful coronary artery bypass. Six weeks later, after a physical examination of the chest, she had unbearable sharp, stabbing pain around the incision which was not responding to nerve blocks, analgesics, nonsteroidal anti inflammatory agents, and epidural blocks. The pain was responsive to mexilitine and disappeared after three weeks of treatment. PMID- 9360428 TI - Primary non-Hodgkin lymphoma of the parotid gland. AB - The rarity of primary non-Hodgkin lymphomas of the parotid gland triggers this report on a case treated and now in the fourth year of follow-up, which offers the opportunity for a review of the literature on the subject. The paper also describes the criteria for accurate classification, the diagnostic tools available and the problems of differential diagnosis. Treatment protocols and survival are also considered. PMID- 9360429 TI - A case of relapsing polychondritis presenting as mediastinal syndrome, diagnosed by CT scans of the trachea and head. AB - OBJECTIVE: The aim of this study is to evaluate the significance of CT scans of the trachea and head in the diagnosis of Relapsing Polychondritis (RP). DESIGN: Relapsing polychondritis is a disease involving cartilaginous structures, particularly those of the ears, nose and trachea. Diagnosis is based on specific clinical features and immuno-histopathological evaluation of the cartilages involved. SETTING AND PATIENTS: We describe a case of RP in which the most evident clinical signs (cough, dyspnoea, vertigo, tinnitus, headache, oedema of the face and shoulders and fever), led us first to suspect a mediastinal compression syndrome. INTERVENTION: A CT scan of the trachea and head revealed details which established the correct diagnosis, supported by other typical RP symptoms and by histopathological examination of the cartilage. MAIN OUTCOME MEASURES: Evaluation by CT scan of the chest, the mediastinum, the head and the pinnae. RESULTS: CT scanning revealed thickening and calcification of the anterolateral tracheal wall and main bronchi besides marked narrowing of the trachea. CT of the head showed calcification also of the external auditory meatus and part of the pinnae. CONCLUSION: We consider that CT scan of the trachea and head is helpful in evaluating the bronchial tree, the auditory meatus and pinnae as well as being a valid tool for the final diagnosis and in following the course of the disease. PMID- 9360430 TI - Contribution of immunological mechanism in a case of ochronotic arthropathy. AB - We have studied cell mediated and humoral response on the synovial fluid and peripheral blood of a 60-year-old man affected by ochronosis. Results showed raised percentages of CD3+, CD8+, HLA-DR+ and CD25+ T cells, presence of TNF, enhanced levels of immunoglobulins and low levels of C3 in the synovial fluid, and a higher rate of HLA-DR+ and CD25+ T lymphocytes in peripheral blood. These data suggest a possible role of immunological response the evolution of an ochronotic arthropathy. PMID- 9360431 TI - Single-dose ceftriaxone versus multiple-dose cefuroxime for antimicrobial chemoprophylaxis in pleuropulmonary surgery. AB - The efficacy and safety of single-dose ceftriaxone and multiple-dose cefuroxime as antibiotic prophylaxis for pleuropulmonary surgery were compared in 160 patients undergoing thoracic surgery. 82 patients received a single-dose of 2 g ceftriaxone intravenous prior to surgery. Seventy-eight patients received 1.5 g of cefuroxime i.v. prior to surgery and 750 mg i.m. every 8 hours for the next 48 hours. Patients were observed daily for ten days postoperatively and monitored for signs of wound and systemic infections. Postoperative infections were studied in each treatment group. No adverse postoperative infections effects or laboratory abnormalities attributable to either drug were noted. Those results indicate that single-dose ceftriaxone was as effective and well-tolerated as a multiple-dose cefuroxime in preventing postoperative infections following pleuropulmonary surgery. PMID- 9360433 TI - Failure to thrive: a general pediatrician's perspective. PMID- 9360432 TI - Danazol induced cholestasis: pathogenetic hypothesis. AB - Numerous mechanisms have been proposed to account for deficient bilirubin excretion and the pathogenesis of estrogen and steroid (danazol) induced intrahepatic cholestasis. Our hypothesis is based on the fact that danazol is administered in the treatment of pulmonary emphysema because it stimulates synthesis of alpha-1 antitrypsin and that other estrogen glucuro-conjugated metabolites are P-glycoprotein substrates. We believe that genetic alterations of alpha-1 antitrypsin and P-glycoprotein, either alone or in association with known pathogenetic mechanisms, may explain the onset of danazol induced cholestasis and justify the difference in its varying duration and intensity. PMID- 9360434 TI - Index of suspicion. Case 1. Fever and altered mental status. PMID- 9360435 TI - Index of suspicion. Case 2. Methemoglobinemia. PMID- 9360436 TI - Index of suspicion. Case 3. Hemolytic-uremic syndrome. PMID- 9360437 TI - Diabetes mellitus. AB - The effective management of diabetes in children and teens requires a daily balancing of insulin administration, food intake, and exercise. To optimize outcome and avoid the neuropathic and microcirculatory effects of hyperglycemia, blood glucose levels should be maintained within a targeted range, which can be accomplished with frequent evaluation and adjustment of the overall treatment regimen. This requires meticulous attention to the disease not only by the patient and family, but by school personnel, baby sisters, coaches, and other individuals responsible for the child's welfare. Diabetes must be diagnosed as early as possible once the signs and symptoms of insulin deficiency have developed to avoid DKA and the associated risks of this acute metabolic disturbance. In addition, careful monitoring of patient progress and assurance that osmolality is reduced gradually without a rapid decrease in the serum sodium level may be required to help prevent cerebral edema associated with DKA. Individuals at risk for autoimmune diabetes should be offered the option of diabetes screening, and if appropriate, entered into diabetes prevention trials. With these aggressive measures, it is possible to decrease the acute complications and the long-term morbidity of this chronic disease and the tremendous negative impact that it has on the health-care system. PMID- 9360438 TI - Substance abuse among children and adolescents. PMID- 9360440 TI - Oral lesions and HIV. An approach to the diagnosis of oral mucosal lesions for the dentist in private practice. AB - The diagnosis and treatment of oral mucosal lesions in HIV infected individuals is of importance. Oral lesions are reliable indicators of HIV infection and immunosuppression. They are important for staging HIV disease, they have been used as clinical markers in trials to test drug efficacy, and to determine the correct time for institution of treatment for HIV or prophylaxis against opportunistic infections. For the patients, they can cause pain, loss of taste and severe discomfort, leading to decreased quality of life. In more severe cases, they can disseminate and become life-threatening. Several types of lesions may affect the oral mucosa of HIV infected individuals. Although caused by different etiological agents, these lesions may have similar clinical appearance. They may also look like other oral mucosal lesions not commonly associated with HIV infection. Their correct diagnosis is important so adequate treatment can be prescribed. This article provides information to the dentist in private practice on how to elaborate a differential diagnosis and arrive to a final diagnosis of oral mucosal lesions in HIV infected individuals. PMID- 9360441 TI - A little bit of luck. PMID- 9360442 TI - Thyrotoxic periodic paralysis; a reversible cause of paralysis to remember. AB - A young Chinese American male presented with progressive proximal muscle weakness and inability to stand and walk. Investigations revealed marked hypokalemia and thyroid studies revealed hyperthyroidism consistent with Graves' disease. Thyrotoxic periodic paralysis is a rare disorder in the Western hemisphere, yet needs to be considered as a cause particularly in patients of Oriental origin presenting with sudden weakness. The case history and update of current knowledge of thyrotoxic periodic paralysis is presented. PMID- 9360443 TI - Physician impairment and health: a brief overview. PMID- 9360444 TI - Medications exacerbating urinary incontinence in the elderly. PMID- 9360445 TI - Managed care--what's new. PMID- 9360446 TI - SMS public affairs team works for you. PMID- 9360447 TI - Physician's responsibility versus patient's rights. PMID- 9360448 TI - Physicians make advisement, they don't withdraw licenses. PMID- 9360450 TI - The year 2010. PMID- 9360449 TI - Organized medicine and managed care--a proposal for a new and better relationship. PMID- 9360451 TI - 1500 miles south of Alberta, Canada. Interview by Jeremy Pittenger. PMID- 9360452 TI - Physician workforce issues. PMID- 9360453 TI - Clinical pathways offer route to optimal patient care. PMID- 9360454 TI - The chest pain care pathway at Gundersen-Lutheran Medical Center. PMID- 9360455 TI - Clinical pathway for total knee replacement. PMID- 9360456 TI - Practice guideline for preoperative testing (healthy, asymptomatic patient prior to elective surgery). Horizon Healthcare, Inc. PMID- 9360457 TI - Psychiatry pathway: physicians make the process work and find benefits for themselves. PMID- 9360458 TI - Opportunity to improve diabetes care. PMID- 9360459 TI - Malpractice liability and managed care. PMID- 9360460 TI - Models of Collaborative Practice: Preparing for Maternity Care in the 21st century. PMID- 9360461 TI - The challenges and opportunities of collaborative practice. PMID- 9360462 TI - New views on education for maternity care providers. PMID- 9360463 TI - Collaborative practice and health plans. PMID- 9360464 TI - Collaborative practice, regulation, and market forces: a changing health care agenda. PMID- 9360465 TI - Midwives' and physicians' experiences in collaborative practice: a qualitative study. PMID- 9360466 TI - Clinical findings in cows after experimental infection with Ehrlichia phagocytophila. AB - The goal of this study was to determine the clinical signs and course of disease in five lactating cows and in five dry cows after experimental infection with Ehrlichia phagocytophila. Ten clinically healthy Swiss Braunvieh cows, seronegative for E. phagocytophila, were injected with 50 ml of whole blood containing E. phagocytophila. The cows were examined daily for 21 days, and blood samples were collected for microscopic examination of leukocytes for the infective agent. All cows became ill with symptoms of tick-borne fever after an incubation period of 5 to 9 days. The most important clinical signs were pyrexia (40.2-41.7 degrees C), decreased milk production and mildly to moderately disturbed general condition. In addition, there were respiratory symptoms such as polypnea, nasal discharge, cough and abnormal lung sounds. Clinical signs returned to normal in all cows without treatment after an average of 8 days. E. phagocytophila bodies were seen in leukocytes 5-8 days after infection and were present for 6-14 days. The course of disease was more severe in dry cows than in lactating cows. It can be concluded that experimental infection of cows with E. phagocytophila generally has a mild course. However, the associated decrease in milk production may be of economic importance. PMID- 9360467 TI - An apparent flea-allergy dermatitis in kids and lambs. AB - Heavy infestation of lambs in two herds and kids in one herd with the cat flea, Ctenocephalides felis felis, accompanied by severe anaemia, eosinophilia and exudative dermatitis, is described. Flea infestation was more widespread during the summer months, when optimal climatic conditions for flea development prevail. The clinical and histological findings are discussed in the light of the pertinent literature. Recovery of the affected animals and normalization of the haematological values were observed after the insecticide treatment. Flea allergic dermatitis is apparently the cause of the skin lesions in the lambs and kids. PMID- 9360468 TI - Immunohistochemical study of a non-invasive canine thymoma: a case report. AB - We describe a case of canine thymoma in an 11-year-old pure-bred female Spanish Mastiff. On post-mortem examination a big mass was found in the thoracic cavity. Histologically the neoplastic parenchyma showed great structural variability; the principal findings included the presence of tumour cells forming cords or sheets, cystic formations, Hassall-corpuscle like squamous formations, and small or intermediate calibre vessels encircled by areas with eosinophilic material and lymphocytes. In order to determine the histogenesis of the thymic neoplasia we used immunohistochemical techniques specific for different markers: cytokeratins, vimentin, desmin and neuron specific enolase. A strong positive immunoreaction of tumour cells to wide spectrum cytokeratins confirmed the epithelial origin of the neoplasia. PMID- 9360469 TI - Blood metabolites and hormones--especially glucose and insulin--in veal calves: effects of age and nutrition. AB - Veal calves often develop insulin resistance, hyperglycaemia and glucosuria. We have studied effects of age and nutrition on blood metabolites and hormones, with major emphasis on glucose and insulin, in four groups of veal calves from 66-69 kg until slaughter at 175-196 kg. Calves were fed milk replacers which differed with respect to lactose, total sugar, protein and fat content. Mean intakes in groups 1, 2, 3 and 4 of lactose (1.24, 1.08, 0.95 and 0.66 kg/d), total sugar (1.27, 1.10, 1.01 and 96 kg/d), crude protein (0.40, 0.48, 0.65 and 0.49 kg/d) and crude fat (0.32, 0.31, 0.37 and 0.46 kg/d) were different. Average daily gains were 1.46-1.49 kg and feed/gain ratios were 1.49-1.61 kg/kg. Glucose and insulin concentrations were not associated with protein and fat intakes, but followed lactose and total sugar intakes, albeit differently at the start and end of the growth trial. Thus, insulin concentrations were higher (P < 0.05) at the end than at start of the growth trial in all 4 groups, whereas glucose concentrations increased (P < 0.05) with increasing age in only group 2. In conclusion, lactose and total sugar intakes affected the degree of hyperglycaemia and modified hyperinsulinemia at a given age, but the age-dependent rise of insulin concentrations could not be explained by hyperglycaemia alone. PMID- 9360470 TI - Bacteriological findings, blood chemistry profile and plasma endotoxin levels in bitches with pyometra or other uterine diseases. AB - Uteri from 60 bitches with a clinical diagnosis of pyometra, or with an enlarged uterus as revealed radiographically or ultrasonographically, underwent histopathological examination, at which a diagnosis of pyometra was established in 48 of the 60 (80%) cases. Escherichia coli was isolated from 43 (90%) of the 48 uteri with pyometra. In 8 of the 60 cases, other pathological uterine conditions, such as endometrial hyperplasia, adenomyosis, mucometra or hydrometra, were diagnosed histopathologically. No bacterial growth was observed in the uteri of these 8 cases. Four of the 60 bitches (6%) showed no pathological changes in the uterus, and in 3 of these no bacteriological growth was seen in the uterus, while in one case a sparse growth of mixed culture was found. Blood samples from bitches with uterine infection caused by gram-negative bacteria showed marked hematological changes. These included higher total WBC counts and a more marked left shift in the differential WBC count than among the other bitches. Toxic degeneration of neutrophils was present among the bitches with gram-negative uterine infection and the serum ALP level was slightly higher than in the other groups of bitches. The plasma endotoxin concentration was determined in 53 bitches before surgery, in 28 bitches after surgery and in 11 control dogs. Only in 7 of the samples was endotoxin detected. The general condition of the bitches included in the present study was only mildly to moderately affected, and in no case indicated severe endotoxemia. PMID- 9360472 TI - PGE2 inhibits glucose uptake in isolated villous epithelial cells of the ovine small intestine. AB - This study was designed to clarify whether PGE2 directly inhibits glucose absorption in villous cells. For this purpose, isolated villous epithelial cells of the ovine small intestine were used, and the uptake of 14C-labelled glucose in the absorptive epithelial cells was measured in the presence and absence of 0.2 mM phlorizin or 10 microM PGE2. In isolated villous epithelial cells of the small intestine in sheep, net glucose absorption was reduced by 68.2% in the presence of phlorizin. This result indicates that most of the glucose in ruminants is absorbed by the specific transporter SGLT1, which is sensitive to phlorizin. PGE2 decreased glucose absorption by 26.5% in isolated villous epithelial cells in sheep, although this glucose absorption did not change in the presence of phlorizin. This result clearly indicates the PGE2 inhibits the phlorizin sensitive glucose absorptive process through direct action on the villous cells of ruminants. PMID- 9360471 TI - Comparisons of prolonged sevoflurane, isoflurane, and halothane anaesthesia combined with nitrous oxide in spontaneously breathing cats. AB - The clinical, cardiopulmonary, haematologic, and serum biochemical effects of sevoflurane, isoflurane and halothane anaesthesia with 66% nitrous oxide, were compared in healthy, premedicated cats breathing spontaneously during 6 h of anaesthesia. Recovery time from anaesthesia with sevoflurane-nitrous oxide was more rapid than that with halothane-nitrous oxide, but it does not differ from that with isoflurane-nitrous oxide. The degree of respiratory acidosis with sevoflurane-nitrous oxide anaesthesia was similar to that with isoflurane-nitrous oxide and was less than that with halothane-nitrous oxide. There were no significant differences among the groups in the heart rate, arterial pressures, haematological and serum biochemical values. The three anaesthetic regimens induced a similar degree of hyperglycemia during anaesthesia. Serum biochemical examination did not reveal apparent hepatic or renal injuries after each anaesthesia. Time-related increases in respiration rate and arterial carbon dioxide partial pressure were observed during prolonged halothane-nitrous oxide anaesthesia. No significant time-related changes in cardiopulmonary variables were observed during either sevoflurane- or isoflurane-nitrous oxide anaesthesia. Therefore, sevoflurane-nitrous oxide may be used as an effective and safe anaesthetic combination similar to isoflurane-nitrous oxide for long-term anaesthesia in healthy cats. PMID- 9360473 TI - An adaptive psychophysical method for subject classification. AB - In psychophysical experiments, one's goal is usually to measure some continuous parameter hypothesized to determine the statistical properties of a subject's responses. Methods are well developed that adaptively manipulate stimulus characteristics in such a way that the reliability of the parameter estimate is maximized. However, such methods are inapplicable in situations in which the goal is to assign subjects to discrete categories, rather than to measure a continuous parameter. This paper introduces a technique that is directly applicable to efficient categorization and that adaptively manipulates stimulus characteristics in such a way that the information obtained from each trial is maximized. This technique is based on the principle of minimum estimated expected entropy, whereby stimulus parameters on each trial are chosen in order to minimize the estimated expected entropy of the a posteriori probability distribution that expresses how likely a subject is to belong to each of a group of mutually exclusive categories. A sample implementation of the technique--the classification of infant subjects according to their audiograms--is then described and evaluated via computer simulation. PMID- 9360474 TI - Reception of Morse code through motional, vibrotactile, and auditory stimulation. AB - The potential for communication through the kinesthetic aspect of the tactual sense was examined in a series of experiments employing Morse code signals. Experienced and inexperienced Morse code operators were trained to identify Morse code signals that were delivered as sequences of motional stimulation through up down displacements (roughly 10 mm) of the fingertip. Performance on this task was compared with that obtained for both vibrotactile and acoustic presentation of Morse code using a 200-Hz tone delivered either to the fingertip through a minishaker or diotically to the two ears under headphones. For all three modalities, the ability to receive Morse code was examined as a function of presentation rate for tasks including identification of single letters, random three-letter sequences, common words, and sentences. Equivalent word-rate measures (i.e., product of percent correct scores and stimulus presentation rate) were nearly twice as high for auditory presentation as for vibrotactile stimulation, which in turn was about 1.3 times that for motional stimulation. The experienced subjects outperformed the inexperienced subjects by amounts that increased with task complexity. For example, the former were able to receive sentences at 18 words/min with motional stimulation, whereas the latter, following 75 h of training, were unable to perform this task. The present results and those of other research with tactual communication systems are compared, particularly regarding estimates of information-transfer rates. PMID- 9360475 TI - The contribution of head motion cues to localization of low-pass noise. AB - Localization of low-pass sounds was tested in relation to aspects of Wallach's (1939, 1940) hypotheses about the role of head movement in front/back and elevation discrimination. With a 3-sec signal, free movement of the head offered only small advantage over a single rotation through 45 degrees for detecting elevation differences. Very slight rotation, as observed using a 0.5-sec signal, seemed sufficient to prevent front/back confusion. Cluster analysis showed that, in detecting elevation, some listeners benefited from rotation, some benefited from natural movement, and some from both. Evidence was found indicating that a moving auditory system generates information for the whereabouts of sounds, even when the movement does not result in the listener facing the source. Results offer significant if partial support for Wallach's hypotheses. PMID- 9360476 TI - Comparing exemplar-retrieval and decision-bound models of speeded perceptual classification. AB - The authors compared the exemplar-based random-walk (EBRW) model of Nosofsky and Palmeri (1997) and the decision-bound model (DBM) of Ashby and Maddox (1994; Maddox & Ashby, 1996) on their ability to predict performance in Garner's (1974) speeded classification tasks. A key question was the extent to which the models could predict facilitation in the correlated task and interference in the filtering task, in situations involving integral-dimension stimuli. To obtain rigorous constraints for model evaluation, the goal was to fit the detailed structure of the response time (RT) distribution data associated with each individual stimulus in each task. Both models yielded reasonably good global quantitative fits to the RT distribution and accuracy data. However, the DBM failed to properly characterize the interference effects in the filtering task. Apparently, a fundamental limitation of the DBM is that it predicts that the fastest RTs in the filtering task should be faster than the fastest RTs in the control task, whereas the opposite pattern was observed in our data. PMID- 9360477 TI - Form and objective of the decision rule in absolute identification. AB - In several conditions of a line length identification experiment, the subjects' decision making strategies were systematically biased against the responses on the edges of the stimulus range. When the range and number of the stimuli were small, the bias caused the percentage of correct responses to be highest in the center and lowest on the extremes of the range. Two general classes of decision rules that would explain these results are considered. The first class assumes that subjects intend to adopt an optimal decision rule, but systematically misrepresent one or more parameters of the decision making context. The second class assumes that subjects use a different measure of performance than the one assumed by the experimenter: instead of maximizing the chances of a correct response, the subject attempts to minimize the expected size of the response error (a "fidelity criterion"). In a second experiment, extended experience and feedback did not diminish the bias effect, but explicitly penalizing all response errors equally, regardless of their size, did reduce or eliminate it in some subjects. Both results favor the fidelity criterion over the optimal rule. PMID- 9360478 TI - What the reader's eye tells the mind's ear: silent reading activates inner speech. AB - Although copious research has investigated the role of phonology in reading, little research has investigated the precise nature of the entailed speech representations. The present study examined the similarity of "inner speech" in reading to overt speech. Two lexical decision experiments (in which participants gave speeded word/nonword classifications to letter strings) assessed the effects of implicit variations in vowel and word-initial consonant length. Responses were generally slower for phonetically long stimuli than for phonetically short stimuli, despite equal orthographic lengths. Moreover, the phonetic length effects displayed principled interactions with common factors known to affect lexical decisions, such as word frequency and the similarity of words to nonwords. Both phonetic length effects were stronger among slower readers. The data suggest that acoustic representations activated in silent reading are best characterized as inner speech rather than as abstract phonological codes. PMID- 9360479 TI - Expectancies generated by melodic intervals: evaluation of principles of melodic implication in a melody-completion task. AB - Bottom-up principles of melodic implication (Narmour, 1990) were evaluated in a melody-completion task. One hundred subjects (50 low training; 50 high training in music) were presented each of eight melodic intervals. For each interval, the subjects were asked to compose a short melody on a piano keyboard, treating the interval provided as the first two notes of the melody. For each melody, the first response--the note immediately following the initial interval--was analyzed. Multinomial log linear analyses were conducted to assess the extent to which responses could be predicted by Narmour's (1990, 1992) bottom-up principles. Support was found for all of Narmour's principles, and two additional predictors based on implied tonal structure. Responses of low- and high-training groups were similar. PMID- 9360480 TI - Dynamic, state-dependent thresholds for the perception of single-element apparent motion: bistability from local cooperativity. AB - Previous studies have indicated that the formation of coherent patterns for multielement motion displays depends on global cooperative interactions among large ensembles of spatially distributed motion detectors. These interactions enhance certain motion directions and suppress others. It is reported here that perceiving one element moving between two nearby locations likewise is subject to cooperative influences (possibly facilitating and inhibiting interactions within a local ensemble of overlapping detectors). Thresholds depending on luminance contrast were measured for a generalized single-element apparent-motion stimulus, and evidence for spontaneous switching and hysteresis effects indicated that motion perception near the 50% threshold was bistable. That is, for conditions in which motion and nonmotion were perceived half the time, the two percepts were distinct; when one was perceived, it clearly was discriminable from the other. These results indicated that (1) single-element apparent-motion thresholds depended on the immediately preceding state of the ensemble of motion detectors responding to the stimulus, and (2) the stimulus activation of individual motion detectors always might be influenced by recurrent, cooperative interactions resulting from the detectors' being embedded within interconnected ensembles. PMID- 9360481 TI - Response force is sensitive to the temporal uncertainty of response stimuli. AB - Three experiments examined whether temporal uncertainty about the delivery of a response stimulus affects response force in a simple reaction time (RT) situation. All experiments manipulated the foreperiod; that is, the interval between a warning signal and the response stimulus. In the constant condition, foreperiod length was kept constant over a block of trials but changed from block to block. In the variable condition, foreperiod length varied randomly from trial to trial. A visual warning and response stimulus were used in Experiment 1; response force decreased with foreperiod length in the variable condition, but increased in the constant condition. This result is consistent with the hypothesis that responses are less forceful when the temporal occurrence of the response stimulus is predictable. In a second experiment with an auditory warning signal and a response stimulus, response force was less sensitive to foreperiod manipulations. The third experiment manipulated both the modality and the intensity of the response signal and employed a tactile warning signal. This experiment indicated that neither the modality nor the intensity of the response signal affects the relation between response force and foreperiod length. An extension of Naatanen's (1971) motor-readiness model accounts for the main results. PMID- 9360482 TI - Global context effects on musical expectancy. AB - The effects of global harmonic contexts on expectancy formation were studied in a set of three experiments. Eight-chord sequences were presented to subjects. Expectations for the last chord were varied by manipulating the harmonic context created by the first six: in one context, the last chord was part of an authentic cadence (V-I), whereas in the other, it was a fourth harmonic degree following a full cadence (I-IV). Given this change in harmonic function, the last chord was assumed to be more expected in the former context, all the other local parameters being held constant. The effect of global context on expectancy formation was supported by the fact that subjects reported a lower degree of completion for sequences ending on an unexpected chord (Experiment 1), took longer to decide whether the last chord belonged to the sequence when the last chord was unexpected (Experiment 2), and took longer to decide whether the last chord was consonant or dissonant when it was unexpected (Experiment 3). These results are discussed with reference to current models of tonal cognition. PMID- 9360484 TI - Attentional resources in timing: interference effects in concurrent temporal and nontemporal working memory tasks. AB - Three experiments examined interference effects in concurrent temporal and nontemporal tasks. The timing task in each experiment required subjects to generate a series of 2- or 5-sec temporal productions. The nontemporal tasks were pursuit rotor tracking (Experiment 1), visual search (Experiment 2), and mental arithmetic (Experiment 3). Each nontemporal task had two levels of difficulty. All tasks were performed under both single- and dual-task conditions. A simple attentional allocation model predicts bidirectional interference between concurrent tasks. The main results showed the classic interference effect in timing. That is, the concurrent nontemporal tasks caused temporal productions to become longer (longer productions represent a shortening of perceived time) and/or more variable than did timing-only conditions. In general, the difficult version of each nontemporal task disrupted timing more than the easier version. The timing data also exhibited a serial lengthening effect, in which temporal productions became longer across trials. Nontemporal task performance showed a mixed pattern. Tracking and visual search were essentially unaffected by the addition of a timing task, whereas mental arithmetic was disrupted by concurrent timing. These results call for a modification of the attentional allocation model to incorporate the idea of specialized processing resources. Two major theoretical frameworks--multiple resource theory and the working memory model- are critically evaluated with respect to the resource demands of timing and temporal/nontemporal dual-task performance. PMID- 9360483 TI - Echo suppression and discrimination suppression aspects of the precedence effect. AB - The precedence effect is a phenomenon that may occur when a sound from one direction (the lead) is followed within a few milliseconds by the same or a similar sound from another direction (the lag, or the echo). Typically, the lag sound is not heard as a separate event, and changes in the lag sound's direction cannot be discriminated. The hypothesis is proposed in this study that these two aspects of precedence (echo suppression and discrimination suppression) are at least partially independent phenomena. Two experiments were conducted in which pairs of noise bursts were presented to subjects from two loudspeakers in the horizontal plane to simulate a lead sound and a lag sound (the echo). Echo suppression threshold was measured as the minimum echo delay at which subjects reported hearing two sounds rather than one sound; discrimination suppression threshold was measured as the minimum echo delay at which subjects could reliably discriminate between two positions of the echo. In Experiment 1, it was found that echo suppression threshold was the same as discrimination suppression threshold when measured with a single burst pair (average 5.4 msec). However, when measured after presentation of a train of burst pairs (a condition that may produce "buildup of suppression"), discrimination suppression threshold increased to 10.4 msec, while echo suppression threshold increased to 26.4 msec. The greater buildup of echo suppression than of discrimination suppression indicates that the two phenomena are distinct under buildup conditions and may be the reflection of different underlying mechanisms. Experiment 2 investigated the effect of the directional properties of the lead and lag sounds on discrimination suppression and echo suppression. There was no consistent effect of the spatial separation between lead and lag sources on discrimination suppression or echo suppression, nor was there any consistent difference between the two types of thresholds (overall average threshold was 5.9 msec). The negative result in Experiment 2 may have been due to the measurements being obtained only for single stimulus conditions and not for buildup conditions that may involve more central processing by the auditory system. PMID- 9360485 TI - Perceiving the causes of coarticulatory acoustic variation: consonant voicing and vowel pitch. AB - Coarticulatory acoustic variation is presumed to be caused by temporally overlapping linguistically significant gestures of the vocal tract. The complex acoustic consequences of such gestures can be hypothesized to specify them without recourse to context-sensitive representations of phonetic segments. When the consequences of separate gestures converge on a common acoustic dimension (e.g., fundamental frequency), perceptual parsing of the acoustic consequences of overlapping spoken gestures, rather than associations of acoustic features, is required to resolve the distinct gestural events. Direct tests of this theory were conducted. These tests revealed mutual influences of (1) fundamental frequency during a vowel on prior consonant perception, and (2) consonant identity on following vowel stress and pitch perception. The results of these converging tests lead to the conclusion that speech perception involves a process in which acoustic information for coarticulated gestures is parsed from the stream of speech. PMID- 9360486 TI - Holding an object one is looking at: kinesthetic information on the object's distance does not improve visual judgments of its size. AB - Visual judgements of distance are often inaccurate. Nevertheless, information on distance must be procured if retinal image size is to be used to judge an object's dimensions. In the present study, we examined whether kinesthetic information about an object's distance--based on the posture of the arm and hand when holding it--influences the object's perceived size. Subjects were presented with a computer simulation of a cube. This cube's position was coupled to that of a rod in the subject's hand. Its size was varied between presentations. Subjects had to judge whether the cube they saw was larger than, smaller than, or the same size as a reference. On some presentations, a small difference was introduced between the positions of the rod and of the simulated cube. When the simulated cube was slightly closer than the rod, subjects judged the cube to be larger. When it was farther away, they judged it to be smaller. We show that these changes in perceived size are due to alterations in the cube's distance from the subject rather than to kinesthetic information. PMID- 9360487 TI - MALDI MS and strategies for protein analysis. PMID- 9360488 TI - Trace determination of hydroxyl radical in biological systems. AB - A simple and highly sensitive method to quantify the rates of production of OH in biological systems is described. This method employs the reaction between OH and dimethyl sulfoxide to generate quantitatively a methyl radical, which then reacts with a fluorescamine-derivatized nitroxide to produce the stable O methylhydroxylamine. This O-methylhydroxylamine is separated by reversed-phase high-performance liquid chromatography and quantified fluorometrically. The estimated detection limit of the O-methylhydroxylamine is 3.5 nM for a 50 microL injection at a signal to noise ratio of 2. The method is applied to the determination of the rates of OH production in a biologically relevant model system and in a mouse epidermal cell line treated with a quinone anticancer compound. PMID- 9360489 TI - Determination of acid dissociation constants of peptide side-chain functional groups by two-dimensional NMR. AB - An NMR method is described for determining residue-specific acid dissociation constants for peptides which contain more than one residue of the same acidic or basic amino acid. The method is based on using the differences in C alpha H proton chemical shifts which result from peptide sequence nearest-neighbor and possibly secondary structure effects to resolve resonances for carbon-bonded reporter protons adjacent to each side-chain acidic group in two-dimensional total correlation spectroscopy (TOC-SY) spectra. Acid dissociation constants were determined for each of the four lysine side-chain ammonium groups of the peptide Lys-Asn-Asn-Gln-Lys-Ser-Glu-Pro-Leu-Ile-Gly-Arg-Lys-Lys-Thr-NH2. Resonances for the C epsilon H2 protons adjacent to the four side-chain ammonium groups, which overlap in the one-dimensional spectrum, were resolved using the C alpha H-C epsilon H2 cross peaks in the TOCSY spectrum. Chemical shift-pH titration data were obtained for each lysine side-chain ammonium group from one-dimensional subspectra taken from two-dimensional TOCSY spectra measured as a function of pH. The pKAs of the Lys1, Lys5, Lys13, and Lys14 side-chain ammonium groups were determined to be 11.14 +/- 0.01, 10.95 +/- 0.01, 10.96 +/- 0.02, and 11.09 +/- 0.02, respectively. The chemical shift-pH titration data were also analyzed by a pH-independent procedure to obtain relative acid dissociation constants: KA(Lys1)/KA(Lys5) = 0.663 +/- 0.009, KA(Lys1)/KA(Lys13) = 0.703 +/- 0.014, and KA(Lys1)/KA(Lys14) = 0.910 +/- 0.009, which correspond to relative acidities for the side-chain ammonium groups of Lys1, Lys5, Lys13, and Lys14 of 1:1.508:1.422:1.099. To further demonstrate the utility of this method, acid dissociation constants were determined for the six acidic groups of the peptide Glu-Ala-Cys-Asn-Pro-Ala-Ala-Gly-Arg-His-Tyr-Ser-Cys-NH2. Chemical shift-pH titration curves were obtained for the C beta H2 protons adjacent to the two cysteine thiol groups using one-dimensional subspectra taken from TOCSY spectra measured as a function of pH. The pKAs of the CyS3 and Cys13 thiol groups were determined to be 9.21 +/- 0.07 and 8.60 +/- 0.06, respectively. The relative acid dissociation constants (KA(Cys3)/ (KA(Cys13)) were found to be 0.21 +/- 0.06 by the pH-independent calculation procedure. PMID- 9360490 TI - A sequencing method for RNA oligonucleotides based on mass spectrometry. AB - Synthetic oligoribonucleotides up to 22 bases have been sequenced by observing different kinetics in exonuclease-induced phosphodiester bond hydrolysis and detecting the fragments by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Common mass spectrometric sequencing methods have disadvantages concerning read length, cost, and specialist instrumentation using RNA as the target molecule because uridine and cytidine have similar masses. Now we are in the position to distinguish U and C by different peak intensities. The method proposed has been verified using specific endonucleases and 13C-labeled nucleotides. This new nongel-based and nonlabeling sequencing strategy offers first RNA sequencing data using the advantages of fast and accurate MALDI-TOF-MS. Preparation steps and measurements are performed in less than 1 h. PMID- 9360491 TI - Surface plasmon resonance biomolecular interaction analysis mass spectrometry. 1. Chip-based analysis. AB - The use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) in concert with surface plasmon resonance-based biomolecular interaction analysis (SPR-BIA) is reported. A chip-based biosensor unit was used to simultaneously monitor biomolecular interactions taking place on four different regions of the sensor chip (flow cells). Species retained during SPR-BIA were then identified by performing MALDI-TOF directly from within the area of the flow cells. Analyses were performed on an antibody/antigen/antibody system with detection limits in the low-femtomole range. The combined assay demonstrates the use of SPR-BIA to evaluate the relative stability of sequential solution-phase interactions, as well as, upon MALDI-TOF analysis, the ability to unambiguously confirm the presence of species retained during the interaction analysis. PMID- 9360492 TI - Surface plasmon resonance biomolecular interaction analysis mass spectrometry. 2. Fiber optic-based analysis. AB - Fiber optic probe-based surface plasmon resonance (SPR) detection has been used in combination with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry for the rapid, sensitive, and selective detection of biomolecules. SPR was used to monitor the covalent immobilization of a polyclonal antibody to the surface of a fiber optic probe. The derivatized probe was then used for the selective detection (from solution) of the corresponding antigen and a secondary antibody directed toward the antigen. Species retained during the SPR detection process were next analyzed by direct MALDI-TOF analysis of the probe surface (after exposed to the MALDI matrix and introduction into the mass spectrometer). The combined approach allowed for the two-dimensional detection of biomolecules, with SPR analysis yielding quantitative information pertinent to the binding events and MALDI-TOF providing details on the qualitative nature of the binding partners. PMID- 9360493 TI - Laser photodissociation of insulin ions generated by matrix-assisted laser desorption. AB - A novel method for studying the ionization step of matrix-assisted laser desorption/ionization (MALDI) is demonstrated. A 193-nm pulse from an ArF excimer laser is used to photodissociate a portion of a plume of insulin ions generated by MALDI. Laser photodissociation (LPD) creates a "hole", i.e., a negative spike in the insulin peak in the time-of-flight (TOF) mass spectrum. The position of the hole in the mass spectrum provides useful measurements of the characteristics (position, time, and velocity) of insulin ions shortly after their creation. Although the performance of the method can be further improved, the data obtained could be used to refine our current understanding of MALDI and to improve the resolution of MALDI-TOFMS. PMID- 9360494 TI - Use of binary solvent systems in the MALDI-TOF analysis of poly(methyl methacrylate). AB - Two of the main problems associated with matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) analysis of polymers are mass discrimination and poor reproducibility. This paper shows that the use of binary solvent systems is one of the causes of these problems. It was observed that the presence of a second solvent such as water in the PMMA solution could cause significant mass discrimination and varying polymer distributions, which can be varied by over 50% when PMMA 4K was used as the polymer sample. In general, a small amount of a second solvent tends to result in less severe mass discrimination but varying distributions, while large amounts of a second solvent are more likely to cause more systematic and severe mass discrimination. Except for a few cases, mass discrimination was observed to be against larger oligomers. Moreover, it was observed that this effect varies with the matrix, main solvent, and sample preparation used. The importance of this work is that it provides guidance for one to develop a better sample preparation protocol to minimize the mass discrimination and poor reproducibility problems. Several potential sources leading to water contamination were identified. Finally, a simple method to verify if amounts of a second solvent are sufficiently high to cause mass discrimination is also discussed. PMID- 9360495 TI - Capillary electrochromatography with gradient elution. AB - A capillary electrochromatograph incorporating a gradient-forming system generally employed in HPLC is described, and the use of gradient elution in reversed phase electrochromatography is demonstrated by the separation of PTH amino acids and steroid hormones. The gradient former employs two reciprocating displacement pumps to control the composition of the eluent in the reservoir at the column inlet with time in a controlled manner. Thus, the composition of the mobile phase flowing through the column and driven by electrosmotic forces can be changed with time in a controlled fashion as customary in HPLC with gradient elution. The design of the system allows also for isocratic elution by pumping the eluent of constant composition through the cavity at the column inlet and thus continuously supplying fresh buffer. The eluent gradient is generated by the two pumps and a 10 microL mixer. From there the liquid passes at a flow rate of 0.1-0.2 mL/min through the 17 microL cavity housing the column inlet and an electrode. The flow of the mobile phase was electrosmotic at an effective overall electric field strength of 500-1500 V/cm through a 50 microns x 20/12 cm capillary column packed with 3.5 microns octadecylated silica particles. Gradient profiles generated in this manner were highly reproducible. The same-day and day today reproducibilities of the electrosmotic flow were found to be better than 3%. The use of the capillary electrochromatographic system was demonstrated with isocratic and gradient elution for the separation of complex mixtures of biologically interesting substances. The influence of the column temperature on the electrosmotic flow velocity and retention of PTH-amino acids was also investigated. PMID- 9360496 TI - Improved ruggedness for membrane-based amperometric sensors using a pulsed amperometric method. AB - This paper introduces a new approach to the use of membrane-based amperometric sensors which is expected to improve the ruggedness of these sensors significantly relative to the steady-state method in common use. In this new method, the fixed-voltage source used with the conventional steady-state method is replaced by a pulsed-voltage source. Unlike the fixed-source approach, which yields steady-state currents corresponding to large differences between analyte concentrations inside and outside the isolating membrane, the pulsed-source approach permits measurement of currents corresponding to near-equilibrium conditions between solutions inside and outside the membrane. Because the measured currents correspond to near-equilibrium conditions, results are expected to be virtually independent of variables that affect rates of mass transport to and across the membrane. The new approach is evaluated using the "oxygen electrode" as a model system. Results obtained using the new method are compared with results obtained using the conventional steady-state option as well as a coulometric approach described recently. The reproducibility of the pulsed amperometric approach and the scatter of data about least-squares calibration lines are an order of magnitude or more better than for the conventional steady state option. As expected, the pulsed amperometric method is 40-100-fold less dependent on changes in membrane thickness, stirring rate, and temperature than the conventional steady-state option. PMID- 9360497 TI - 9th Annual Transcatheter Cardiovascular Therapeutics Symposium. Washington, DC, September 24-28, 1997. Abstracts. PMID- 9360498 TI - 70th Scientific Sessions of the American Heart Association. Orlando, Florida, November 9-12, 1997. Abstracts. PMID- 9360499 TI - American Association for the Study of Liver Diseases Postgraduate courses and 48th annual meeting. Chicago, Illinois, November 7-11, 1997. Abstracts. PMID- 9360500 TI - Radiological Society of North America 83rd scientific assembly and annual meeting. Chicago, Illinois, November 30-December 5, 1997. Abstracts. PMID- 9360501 TI - Hereditary defect in biosynthesis of aldosterone: aldosterone synthase deficiency 1964-1997. AB - We studied two of the three patients with a hereditary defect in the biosynthesis of aldosterone originally described by Visser and Cost in 1964. All three presented as newborns with salt-losing syndrome and failure to thrive. The original biochemical studies showed a defect in the 18-hydroxylation of corticosterone. According to the nomenclature proposed by Ulick, this defect would be termed corticosterone methyl oxidase deficiency type I. We measured plasma steroids in the untreated adult patients and performed molecular genetic studies. Aldosterone and 18-OH-corticosterone were decreased, whereas corticosterone and 11-deoxycorticosterone were elevated, thus confirming the diagnosis of corticosterone methyl oxidase deficiency type I. Cortisol and its precursors were in the normal range. Genetic defects in the gene CYP11B2 encoding aldosterone synthase (P450c11Aldo) have been described in a few cases. We identified a homozygous single base exchange (G to T) in codon 255 (GAG) causing a premature stop codon E255X (TAG). This mutation destroys a Aoc II restriction site. Digestion of a PCR fragment containing exon 4 of CYP11B2 (261 bp) with this restriction enzyme revealed in the two patients homozygous for the E255X mutation only a 261-bp fragment, whereas the heterozygous parents had three fragments (261 bp from the mutant allele and 194 and 67 bp from the wild-type allele). The mutant enzyme had lost the five terminal exons containing the heme binding site, and thus there was a loss of function enzyme. We conclude that the biochemical phenotype of these prismatic cases of congenital hypoaldosteronism can be explained by the patients genotype. PMID- 9360503 TI - Calcinosis universalis complicating juvenile dermatomyositis: resolution during probenecid therapy. PMID- 9360502 TI - Phenotype: genotype relationships in growth hormone insensitivity syndrome. AB - GH insensitivity syndrome (GHIS) is associated with many different mutations of the GH receptor (GHR) gene. We examined the phenotypic and biochemical features in 82 GHIS patients from 23 countries, each fulfilling diagnostic criteria of GHIS. There were 45 males and 37 females [mean age, 8.25 yr; mean height, -6.09 SD score, and mean insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3), 7.99 SD score]. Sixty-three were GH-binding protein (GHBP) negative; 19 were GHBP positive (> 10% binding). The mean height in GHBP-negative subjects was -6.5 SD score, and that in GHBP-positive patients was -4.9 SD score (P = < 0.001). Clinical and biochemical heterogeneity was demonstrated by the wide range of height (-2.2 to -10.4 SD score) and IGFBP-3 (-1.4 to -14.7 SD score) values, which were positively correlated (r2 = 0.45; P = < 0.001). This contrasted with the lack of correlation between mean parental height SD score and height SD score (r2 = 0.01). Fifteen different GH receptor gene mutations were identified in 27 patients. All had homozygous defects, except 1 who had a compound heterozygous defect. The mutations were 5 nonsense, 2 frame shift, 4 splice, 4 missense, and 1 compound heterozygote. There was no relationship between mutation type or exon of the GHR gene involved and height or IGFBP-3 SD score. In conclusion, GHIS is associated with wide variation in the severity of clinical and biochemical phenotypes. This variation cannot clearly be accounted for by defects in the GHR gene. Other genetic and/or environmental factors must, therefore, contribute to phenotype in GHIS. PMID- 9360504 TI - Oral 17 beta-estradiol continuously combined with dydrogesterone lowers serum lipoprotein(a) concentrations in healthy postmenopausal women. AB - Lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerosis. Serum Lp(a) concentrations increase after menopause, and postmenopausal estrogen replacement appears to decrease Lp(a) levels. In a randomized, double blind study, we examined the effects of 6-month treatment with daily 17 beta-estradiol (E2; 2 mg, orally) continuously combined with one of four dosages [2.5 mg (n = 41), 5 mg (n = 38), 10 mg (n = 38), and 15 mg (n = 20)] of dydrogesterone on fasting serum Lp(a) concentrations in 137 healthy postmenopausal women. At baseline, no significant differences were noted among the four treatment groups. During the study period of 6 months the median serum Lp(a) concentration decreased significantly from 128 mg/L (range, 5-1660) to 110 mg/L (range, 1-1530) in the total population, corresponding to a reduction of 13% (P < 0.001). The percent changes in serum Lp(a) correlated positively with the percent changes in serum E2 at 3 as well as 6 months of therapy (r = 0.38; P < 0.001 and r = 0.35; P < 0.001, respectively). A dose response of dydrogesterone on serum Lp(a) was not found. In addition, serum lipids and (apo)lipoproteins improved significantly in all four treatment groups. In conclusion, oral E2 continuously combined with dydrogesterone has beneficial effects on the lipid and lipoprotein profile and is effective in lowering Lp(a) concentrations in postmenopausal women. PMID- 9360505 TI - Pituitary-adrenal response in preterm very low birth weight infants after treatment with antenatal corticosteroids. AB - Antenatal corticosteroids have been widely used for the prevention of respiratory distress syndrome in preterm neonates, yet little is known about their effects on the hypothalamic-pituitary-adrenal axis in these infants. We prospectively evaluated pituitary-adrenal function in 61 preterm (< 32 gestational weeks), very low birth weight (< 1500 g) infants on days 7 and 14 of life using the human CRH stimulation test. The baseline and poststimulation plasma ACTH and serum cortisol concentrations did not differ significantly between infants whose mothers received no antenatal corticosteroids, and those whose mothers received 1-2 doses or > 2 doses (mean 7.2 doses) of prenatal dexamethasone (P = > 0.12). The number of doses of dexamethasone and the time intervals between the last dose of drug and delivery did not significantly affect the pituitary-adrenal responsiveness on days 7 and 14 of life. Among infants who did not require mechanical ventilation at the time of the human CRH test, significantly higher plasma ACTH (P < 0.014) and lower serum cortisol concentrations (P < 0.02) were found on day 14 than on day 7. In contrast, none of the poststimulation hormone concentrations were significantly different in ventilated infants between days 7 and 14. The relationship between the blood hormone concentrations in each time epoch (day 7 and day 14) and possible confounding factors including gestational and postconceptional age, birth weight, sex, Apgar scores, mode of delivery, single or higher order births, and mode of ventilation were determined. Plasma ACTH concentrations on day 7 were found to be significantly higher in ventilated than in nonventilated infants (P = 0.006). However, none of the aforementioned factors correlated significantly with plasma ACTH concentrations on day 14. Serum cortisol concentrations on day 7 were significantly higher in infants of greater gestational age (P = 0.039) and birth weight (P = 0.013), with lower Apgar scores at 1 and 5 min (P = 0.021 and P = 0.049, respectively), and in those delivered vaginally (P = 0.047). Similarly, serum cortisol concentrations on day 14 were found to be significantly higher in infants with lower Apgar scores at 1 and 5 min (P = 0.011 and P = 0.014, respectively) and in infants requiring mechanical ventilation (P = 0.014). Our results suggest that single or multiple courses of antenatal dexamethasone have no long-lasting suppressive effects on pituitary adrenal function in preterm, very low birth weight infants. Maturation of pituitary function appears to be more advanced than adrenal function. The organ's ability to respond appropriately to various stressful stimuli indicates that the pituitary-adrenal axis is highly responsive at these early gestational ages. PMID- 9360506 TI - Pathological tumor-node-metastasis (pTNM) staging for papillary and follicular thyroid carcinomas: a retrospective analysis of 700 patients. AB - The TNM classification (tumor-node-metastasis) was adopted by the American Joint Committee on Cancer and the International Union against Cancer a decade ago to avoid heterogeneity of prognostic classification schemes used for differentiated thyroid cancers. To date, however, clinical data based on this classification are lacking. We retrospectively evaluate the prognosis of 700 patients (208 men and 492 women) with papillary (89%) and follicular (11%) thyroid cancers according to the pathological TNM (pTNM) staging system, treated over a 25-yr period (1970 1995). Patients who received primary treatment at our center constituted 87.4% of the cases; the majority underwent total thyroidectomy, followed by 131I ablative therapy in high risk groups, as standard treatment. Clinical and follow-up data were obtained from the medical records and our cancer registry. Disease-free and cancer-specific survival data were analyzed by Kaplan-Meier product limit estimates and Cox proportional hazard models. Patient distribution by the pTNM system were: stage I, 516 patients; stage II, 57 patients; stage III, 104 patients; and stage IV, 23 patients. Over a mean +/- SE follow-up of 11.3 +/- 0.3 yr, the overall cancer recurrence and mortality rates were 20.5% and 8.4%, respectively. However, the respective cancer recurrence and mortality rates were distinctly different in the various pTNM stages: 15.4% and 1.7% in stage I, 22% and 15.8% in stage II, 46.4% and 30% in stage III, and 66.7% and 60.9% in stage IV tumors. Using actuarial survival plots, a clear separation in both disease free survival and cancer-specific survival was noted among all the stages (P < 0.0001). Risk factors analyses showed a significant association between all the prognostic variables used in TNM staging (age, tumor size, extent of primary tumor, and presence of nodal or distant metastases) and the observed end points of recurrence or death from thyroid cancer. After correcting for TNM stages, the risk of cancer recurrence was halved in female compared to male patients, whereas this was 1.7-fold higher in multifocal than unifocal tumors. Conversely, cancer mortality was 3.4-fold higher in follicular than papillary thyroid cancer. In the analysis of effect of primary treatment among 492 patients with tumor more advanced than the T1N0M0 category, patients who underwent less extensive surgery (lobectomy or subtotal thyroidectomy) had a 2.5-fold risk of cancer recurrence (P < 0.0001) and a 2.2-fold risk of death (P < 0.01) compared to those who underwent total or near-total thyroidectomy. Patients not treated with 131I ablation had a 2.1-fold greater risk of cancer recurrence (P < 0.0001) than those given 131I ablation, although no difference was noted in deaths from thyroid cancer. Based on our data, the pTNM classification is useful in distinguishing patients with different prognostic outcomes. However, the small patient numbers in pTNM stages other than stages I precludes us from evaluating its usefulness as a guide for therapy. Until prospective data could be accrued from controlled treatment trials, we support the standard practice of total thyroidectomy followed by 131I ablative therapy (if focal iodide uptake was noted) in patients with papillary thyroid cancer more advanced than the T1N0M0 category or of multicentric nature and in the majority of patients with follicular thyroid cancer. PMID- 9360507 TI - Post-Chernobyl thyroid carcinoma in Belarus children and adolescents: comparison with naturally occurring thyroid carcinoma in Italy and France. AB - After the Chernobyl nuclear accident (April 26, 1986), childhood thyroid carcinoma had a great increase in Belarus and Ukraine, as a consequence of the exposure to iodine radioactive fallout. The epidemiological and clinical features of the disease were studied in 472 patients less than 21 yr old at diagnosis, with differentiated thyroid carcinoma, representing 97.7% of all thyroid carcinomas diagnosed in Belarus between May, 1986, and December, 1995. The results were compared with those of 369 subjects of the same age group, with naturally occurring thyroid carcinoma, observed in Italy and France. Between 1986 and 1989, the number of thyroid cancer cases per year ranged from 3-8 and increased to 31 in 1990, to 66 in 1991, to 72 in 1992, to 93 in 1993, to 96 in 1994, and to 90 in 1995. The age at diagnosis was 14 yr or less in 78.8% (children group) and more than 14, but less than 21, yr in the remaining subjects (adolescents group). Mean (+/- SD) age at the time of the accident was 4.4 +/- 3.4 yr (3.2 +/- 2.3 in children and 8.9 +/- 2.7 in adolescents), the majority of the patients (62.9%) being 5 yr old or less. The time interval between the accident and the diagnosis (latency period) decreased progressively from 7.5 +/- 1.6 yr in children 0-2 yr old at the time of the accident to 6.0 +/- 1.6 yr in those 9-11 yr old. Since 1993, the yearly distribution of new cases showed a decrease in the subjects 9 yr old or more at the time of the accident but not in those 5 yr old or less. This could not be accounted for by a shift of exposed subjects to an age group at diagnosis not included in this study, because only subjects less than 12 yr of age at the time of the accident were considered in this analysis. Mean age at diagnosis in Belarus patients was 11.3 +/- 3.1 yr (10.1 +/- 2.3 in children and 15.7 +/- 1.4 in adolescents), whereas, among patients with naturally-occurring thyroid carcinomas from Italy and France, the majority of cases were diagnosed after 14 yr of age (mean age at diagnosis: 14.6 +/- 4.2 yr). The female-to-male ratio was significantly higher in Italy and France (2.5/1), compared with the ratio of patients from Belarus (1.6/1). Most of the tumors were papillary in both series, but a relatively high proportion of follicular carcinomas (P = 0.0001) was found in Italy/France (15.2%), as opposed to 5.3% in Belarus. Extrathyroidal extension and lymph node metastases were more frequent in Belarus (49.1%, P = 0.0001; and 64.6%, P = 0.002, respectively) with respect to Italy/France (24.9% and 53.9%, respectively). Thyroid lymphocytic infiltration and circulating antithyroperoxidase antibody were more frequent in Belarus patients. Our analysis of Belarus thyroid cancer patients less than 21 yr old showed that the post-Chernobyl increase in thyroid carcinomas involved both children and, to a much lesser extent, adolescents. Subjects 5 yr old or less at the time of the accident accounted for the majority of the patients. No evidence of a decrease in the number of new cases was observed in this age group, as opposed to older subjects. These data support the concept that subjects who were younger at the time of radiation exposure had, and continue to have, a greater risk of developing thyroid carcinoma and strongly suggest that this age group should be carefully monitored in the future. When compared with naturally occurring thyroid carcinoma of the same age group observed in Italy and France, the post-Chernobyl Belarus thyroid carcinomas affected younger subjects, were less influenced by gender, were virtually always papillary, had a greater aggressiveness at presentation, and were more frequently associated with thyroid autoimmunity. PMID- 9360508 TI - Evaluation of the dexamethasone suppression test for the diagnosis of glucocorticoid-remediable aldosteronism. AB - Glucocorticoid-remediable aldosteronism (GRA) is a rare form of inherited hypertension caused by a characteristic gene duplication. With the advent of definitive genetic testing for GRA, the performance of the traditional screening test for GRA, the dexamethasone suppression test (DST), can be evaluated. We compared the DST to direct genetic testing in 24 patients referred for genetic screening for GRA (12 GRA positive and 12 GRA negative) based on clinical and biochemical findings, DST, and family history. Plasma aldosterone was measured before and after oral dexamethasone administration to determine the extent to which aldosterone was suppressed by glucocorticoids in each patient group. The results of the DST in these subjects were also compared to those in 19 historical patients with primary aldosteronism [4 bilateral hyperplasia and 15 aldosterone producing adenoma (APA)] reported previously. The DST differentiated GRA-positive from GRA-negative patients with 92% sensitivity and 100% specificity. Cutoffs based on the post-DST plasma aldosterone level (< 4 ng/dL) or percent suppression compared to baseline (> 80%) were equally effective in correctly diagnosing GRA (only one GRA-positive patient would have been incorrectly diagnosed). However, DST in 15 APA patients revealed that 33% had greater than 80% suppression of aldosterone, and 1 had aldosterone levels below 4 ng/dL. We conclued that a post DST aldosterone level below 4 ng/dL will correctly diagnose GRA patients with high sensitivity and specificity. Suppression compared to baseline can be misleading, as evidenced by the results in APA patients and referred subjects who genetically screened negative. PMID- 9360509 TI - Long-term and low-dose treatment with cabergoline induces macroprolactinoma shrinkage. AB - Cabergoline (CAB), a long-lasting dopamine-agonist, specific for the D2 receptor, is effective in normalizing serum PRL levels in most patients with microprolactinoma or idiopathic hyperprolactinemia. Because few data are presently available on the effects of CAB treatment in macroprolactinomas, the aim of this open-label study was to investigate whether this drug was effective in producing tumor shrinkage, as well as in normalizing PRL levels. Twenty-three patients with macroprolactinoma entered this study 15 patients had had no treatment, whereas the remaining 8 patients had been previously treated with bromocriptine, which was with-drawn because of intolerance. Three of 23 patients had undergone unsuccessful surgery. Pretreatment serum PRL levels ranged from 100 3860 micrograms/L. CAB was administered at a dose of 0.5-3 mg once or twice a week for 12-24 months. Magnetic resonance imaging (MRI) scans were performed before and 3, 6, 12, and 24 months after the beginning of treatment, to evaluate tumor shrinkage, defined as a decrease of at least 80% of baseline tumor volume. After 3-6 months of treatment with a low dose (0.5-1 mg/week), serum PRL levels normalized in 18 patients. In the remaining 5 patients, whose serum PRL levels were not normalized, the dose was increased to 2-3 mg/week. This schedule caused the normalization of PRL levels in 1 patient, whereas in the remaining 4 patients, PRL levels were reduced to 30-82 micrograms/L. A tumor volume reduction greater than 80% at MRI occurred in 14 of 23 patients (61%) after CAB treatment (from 2609.4 +/- 534.7 to 530.1 +/- 141.3 mm3 at the 12-24th month follow-up, P < 0.001). A volume reduction of 41.8 +/- 3.4% was already evident after 3 months (1436 +/- 285.9 mm3; P < 0.001). The complete disappearance of the tumor mass at MRI occurred after 6 months of treatment with CAB in 1 patient, and in 5 patients after 1 yr of treatment. An improvement of visual field defects was obtained in 9 of the 10 patients presenting visual impairment before CAB treatment. The drug was tolerated well by all patients. Only 1 patient experienced mild nausea, which disappeared spontaneously after the 2nd day of treatment. Long-term, a low dose of the D2 receptor agonist CAB significantly reduced tumor volume and normalized serum PRL levels in a great majority of patients bearing macroprolactinoma. This treatment met with excellent patient compliance. This study suggests that CAB can be used as a first choice drug treatment in macroprolactinomas, as already shown for microprolactinomas and idiopathic hyperprolactinemia. PMID- 9360510 TI - Premature hair graying and bone mineral density. AB - In a recent case-control study, premature hair graying was found to be associated with osteopenia, suggesting that this might be a clinically useful risk factor for osteoporosis. We report a reexamination of this possibility in 293 healthy postmenopausal women. Subjects experiencing onset of hair graying in their 20s tended to have lower bone mineral density throughout the skeleton (adjusted for age and weight) than those with onset of graying later in life. The same was true for those in whom the majority of their hair was gray by the age of 40 yr (n = 16), in whom bone density was reduced by 7% in the femoral neck, 8% in the femoral trochanter, and 4% in the total body (P < 0.05) when compared with those not prematurely gray. Bone density at the lumbar spine and Ward's triangle showed similar trends that were not significant. However, premature hair graying explained only 0.6-1.3% of the variance in bone mineral density within the population. We conclude that premature hair graying is associated with low bone density, but that its infrequency in the normal postmenopausal population leads to its accounting for only a tiny fraction of the variance of bone density. PMID- 9360511 TI - Mosaicism due to a somatic mutation of the androgen receptor gene determines phenotype in androgen insensitivity syndrome. AB - Premature stop codons of the human androgen receptor (AR) gene are usually associated with a complete androgen insensitivity syndrome. We, however, identified an adult patient with a 46,XY karyotype carrying a premature stop codon in exon 1 of the AR gene presenting with signs of partial virilization: pubic hair Tanner stage 4 and clitoral enlargement. No other family members were affected. A point mutation at codon position 172 of the AR gene was detected that replaced the original TTA (Leu) with a premature stop codon TGA (opal). Careful examination of the sequencing gel, however, also identified a wild-type allele, indicating a mosaicism. In addition, elimination of the unique AflII recognition site induced by the mutation was incomplete, thus confirming the coexistence of mutant and wild-type AR alleles in the patient. Normal R1881 binding and a normal 110/112-kDa AR doublet in Western immunoblots consolidated the molecular genetic data by demonstrating the expression of the wild-type AR in the patient's genital skin fibroblasts. Transfection analysis revealed that only relatively high plasmid concentrations carrying the mutated AR complementary DNA lead to expression of a shortened AR due to downstream reinitiation at methionine 189. Thus, reinitiation does not play a role in the presentation of the phenotype; rather, the partial virilization is caused by the expression of the wild-type AR due to a somatic mosaic. We conclude that somatic mosaicism of the AR gene can represent a substantial factor for the individual phenotype by shifting it to a higher degree of virilization than expected from the genotype of the mutant allele alone. PMID- 9360512 TI - Effects of [norleucine27]growth hormone-releasing hormone (GHRH) (1-29)-NH2 administration on the immune system of aging men and women. AB - Aging in humans is associated with the decline of functional activities of the GH insulin-like growth factor I (IGF-I) axis and the immune system. Because lymphocytes express GH-IGF-I, as well as GHRH and their respective receptors, restoration of this axis in age-advanced individuals, by the administration of GHRH, may enhance immune cell function. This hypothesis was tested by a single blind randomized placebo-controlled trial of 5 months duration, in which healthy elderly subjects (10 women, 9 men) self-administered sc nightly placebo for 4 weeks, followed by 16 weeks of [norleucine27]GHRH (1-29)-NH2 at a dose of 10 micrograms/kg. Fasting (0800 h-0900 h) blood samples were obtained for immune studies and for measurements of serum concentrations of IGF-I and soluble interleukin (IL)-2 receptor. GH pulsatility was determined in blood samples obtained at 10-min intervals for 12 h (2000 h-0800 h). Freshly isolated peripheral lymphocytes were analyzed by flow cytometric analysis for determination of lymphocyte subsets and monocytes. Mitogen stimulation responses, natural killer cell number and cytotoxicity, basal and stimulated IL-2 secretion from cultured lymphocytes, and IL-2 and IL-2R messenger RNA expression were measured. These studies were conducted at baseline, after placebo, and during GHRH analog administration at 4 and 16 weeks. Treatment with GHRH analog resulted in a significant increase (107 and 70% in men and women, respectively) in the 12 h integrated GH secretion (P < .05) and serum IGF-I levels (28%) (P < .001) in both men and women by 4 weeks and lasted 12 weeks for IGF-I and 16 weeks for GH. Activation of the immune system occurred in both sexes within 4 weeks. A 30% increase (P < .001) in lymphocytes expressing the transferrin receptor (CD71) and in monocytes (CD14) (P < .05) occurred within 4 weeks. By 16 weeks, there was a significant increase (30%) in B cells (CD20) (P < .01), in cells expressing the T cell receptor alpha/beta (20%) (P < .01), and T cell receptor gamma/delta (40%) (P < .0001). There were no changes in the number of T cells (CD3), T cell subsets (CD4, CD8), or natural killer cell (CD57) over the treatment period. The increase in B cell number was associated with enhanced responsiveness (50%) to the B cell mitogens: pokeweed mitogen (P < .01 or better) and Staphylococus aureus cells (P < .001), and a transient increase at 4 weeks in circulating IgG (P < .0001), IgM, and IgA (P < .001). T cells were functionally activated, as evidenced by a 50% increase in responsiveness to phytohemagglutinin (P < .01 or better), 70% increase in the number of lymphocytes expressing the IL-2 receptor (IL-2R) (CD25) (P < .001), and enhanced IL-2R messenger RNA expression and basal IL-2 secretion (50%) (P < .05) at 16 weeks of treatment. Furthermore, circulating soluble IL-2 receptor rose significantly (15%) (P < .05) within 4 weeks of treatment and remained elevated for the duration of the study. There were no sex differences in the immune response to GHRH analog and no adverse effects. These results indicate that GHRH analog administration has profound immune-enhancing effects and may be of therapeutic benefit in states of compromised immune function. PMID- 9360513 TI - Urinary follicle-stimulating hormone for normogonadotropic clomiphene-resistant anovulatory infertility: prospective, randomized comparison between low dose step up and step-down dose regimens. AB - A low dose step-up and step-down regimen for induction of ovulation using urinary FSH was compared in a prospective randomized fashion in 37 normogonadotropic clomiphene-resistant oligo- or amenorrheic infertile women. The objectives was to assess potential differences in duration of treatment, ovarian stimulation (serum FSH levels), and response [serum estradiol (E2) levels and number and size of follicles]. Monitoring (blood sampling and transvaginal sonography) took place on the day of initiation of treatment, the first day of ovarian response as assessed by ultrasound (i.e. the first day a follicle > or = 10 mm could be recognized), the day of hCG administration to induce ovulation, and 3 days thereafter. The median duration of treatment in the low dose step-up group was 18 (range, 7-41) days compared to 9 (range, 4-16) days in the step-down group (P = 0.003), and the total numbers of ampules administered were 20 (range, 7-69) and 14 (range, 7-33), respectively (P = NS). Serum FSH levels from the first day of sonographic ovarian response until the administration of hCG were constant (median increase, 2%/day) in patients receiving the low dose step-up protocol, but showed a decrease (median, 5%/day) in step-down cycles (P < 0.001). Monofollicular growth, defined as not more than one follicle 16 mm or larger on the day of hCG administration, was observed in 56% of low dose step-up and 88% of step-down cycles (P = 0.04). The percentage of patients with normal range periovulatory E2 serum levels (500 1500 pmol/L) was 33% in the low dose step-up group vs. 71% in the step-down group (P = 0.03). We conclude that a step-down protocol for gonadotropin induction of ovulation exhibits a more physiological, late follicular phase FSH serum profile than a low dose step-up protocol. This results in a shorter duration of treatment, a greater number of monofollicular cycles, and more cycles with periovulatory E2 levels within the normal range in the step-down protocol. PMID- 9360514 TI - A therapeutic role of prolactin supplementation in ovarian stimulation for in vitro fertilization: the bromocriptine-rebound method. AB - In a prospective randomized study, we examined whether a novel method of ovarian stimulation, the bromocriptine-rebound method, improves in vitro fertilization (IVF) outcomes compared with the conventional long protocol using GnRH agonist and human menopausal gonadotropin (hMG). Ovulatory women with previous failed IVF embryo transfer using the long protocol were prospectively assigned to either the bromocriptine-rebound method (group 1, 82 cycles) or the long protocol (group 2, 80 cycles). The bromocriptine-rebound method was the same as the long protocol, except that bromocriptine was administered daily from day 4 of the preceding cycle until 7 days before hMG stimulation. The numbers of follicles, fertilized oocytes, and embryos with superior morphology were higher in group 1 than in group 2. The rates of clinical pregnancy and live birth delivery per cycle were significantly higher in group 1 (38% and 33%, respectively) than in group 2 (21% and 19%, respectively). The mean concentration of serum PRL during hMG administration was significantly higher in group 1 than group 2. A significant correlation between the number of superior embryos and PRL concentrations was observed in group 1, but not in group 2. Next, we performed a retrospective study to investigate how the bromocriptine-rebound method exerts its beneficial effects. In the initial IVF with the long protocol, the mean concentration of serum PRL during hMG administration and the expression of PRL receptor (PRLr) messenger ribonucleic acid (mRNA) in granulosa cells were significantly higher in nonpregnant patients than in pregnant ones. When IVF was repeated with the bromocriptine-rebound method in the nonpregnant patients, the expression of PRLr mRNA decreased significantly. In conclusion, the bromocriptine-rebound method enhances embryonic development and the rate of live birth delivery in patients with previous failed IVF using the long protocol. We hypothesize that in the nonpregnant patients using the long protocol, the serum PRL concentration and PRLr mRNA expression are increased to compensate for poor postreceptor responsiveness of granulosa cells to PRL during oocyte maturation. The bromocriptine-rebound method may improve oocyte maturation in such patients by restoring postreceptor responsiveness of granulosa cells to PRL during the hypoprolactinemic period and increasing the PRL concentration by a rebound phenomenon after discontinuation of bromocriptine. PMID- 9360515 TI - Metabolic effects and pharmacokinetics of a growth hormone pulse in healthy adults: relation to age, sex, and body composition. AB - The acute effects of a single GH pulse have previously been studied in young males. It is, however, likely that both the metabolic effects and the pharmacokinetics of GH may differ between age groups and sexes. We studied 36 healthy, clinically nonobese adults of both sexes, who were divided into a young group (mean age, 29.6 yr) and an older group (mean age, 51.0 yr). On 2 separate occasions, they received an i.v. bolus of either GH (200 micrograms) or saline followed by blood sampling for 5 h. Glucose turnover was estimated by infusion of [3-3H]glucose, and indirect calorimetry was performed before and 2 h after the bolus infusions. Body composition (computed tomography scan and dual energy x-ray absorptiometry) was performed at baseline. Baseline levels of serum insulin-like growth factor I (IGF-I) was lower in older subjects, whereas circulating IGF binding protein-1 and lipid intermediates were lower in males than in females. The area under the GH curve was lower in older subjects (young, 3978 +/- 1532 micrograms/L.24 h; older, 1144 +/- 79; P = 0.001), whereas the elimination half life did not differ with age (young, 18.1 +/- 0.9 min; older, 16.4 +/- 0.8; P = NS). The MCR and apparent distribution volume of GH were higher in older subjects [MCR: young, 0.11 +/- 0.02 min/L; older, 0.19 +/- 0.01; P = 0.001; apparent distribution volume: young, 2.5 +/- 0.4 L; older, 4.5 +/- 0.3; P < 0.001). Both MCR and Vd correlated inversely with age and positively with indexes of adiposity. GH significantly increased lipid intermediates, but the response was higher in young subjects and males. By contrast, the ability of GH to acutely suppress IGF-binding protein-1 was more pronounced in older subjects and females. Serum levels of insulin and IGF-I did not differ significantly between GH and saline treatment groups. GH decreased the respiratory exchange ratio and increased resting energy expenditure, with no age or gender differences. A gradual decline over time in plasma levels and rate of turnover of glucose was recorded after both GH and saline. The following conclusions were reached. 1) The MCR and Vd of GH increase with age and correlate positively with fat mass. 2) Older subjects are responsive to the acute lipolytic effects of GH, but the response is higher in young subjects and in males. 3) Adipose tissue may be actively involved in the distribution and clearance of GH. 4) Age, sex, and body composition interact with GH in a complex manner, involving clearance, distribution, and metabolic actions of the hormone. PMID- 9360516 TI - Cigarette smoking and insulin resistance in patients with noninsulin-dependent diabetes mellitus. AB - To evaluate the effects of chronic cigarette smoking on insulin sensitivity in patients with noninsulin-dependent diabetes mellitus (NIDDM), we examined 28 smokers and 12 nonsmokers with NIDDM, of similar sex, age, body mass index, waist/hip ratio, alcohol consumption, physical activity level, glycometabolic control, diabetes duration, and treatment. Insulin and C-peptide responses to oral glucose load were significantly higher in smokers than nonsmokers, whereas glucose levels were not substantially different. During insulin clamp (20 mU/min.m2), carried out in combination with tritiated glucose infusion and indirect calorimetry, total glucose disposal was markedly reduced in smokers vs. nonsmokers [19 +/- 1.2 vs. 33 +/- 5 mumol/min.kg fat-free mass (FFM); P < 0.001], in a dose-dependent fashion (F = 6.8, P < 0.001 by ANOVA when subjects were categorized for number of cigarettes smoked per day). Oxidative (9 +/- 1 vs. 14 +/- 2 mumol/min.kg FFM; P < 0.01) and nonoxidative (10 +/- 1 vs. 19 +/- 4 mumol/min.kg FFM; P < 0.01) pathways of insulin-mediated intracellular glucose metabolism were similarly reduced in smokers vs. nonsmokers. Plasma free fatty acid levels (240 +/- 33 vs. 130 +/- 23 microEq/L; P < 0.05) and lipid oxidation rate (1.39 +/- 0.1 vs. 0.95 +/- 0.2 mumol/ min.kg FFM; P < 0.05) were less suppressed by hyperinsulinemia in smokers than nonsmokers. In conclusion, chronic cigarette smoking seems to markedly aggravate insulin resistance in patients with NIDDM. PMID- 9360517 TI - Management of incidental pituitary microadenomas: a cost-effectiveness analysis. AB - The objective of this study was to compare the cost-effectiveness of four management strategies for a patient with an incidentally discovered asymptomatic pituitary microadenoma. A decision analytic Markov model was used to determine the incremental cost-effectiveness of four clinical management strategies: 1) expectant management, 2) PRL screening, 3) an endocrine screening panel (PRL, insulin-like growth factor I, and 1-mg dexamethasone suppression test), and 4) magnetic resonance imaging (MRI) follow-up. The model incorporated the natural history of incidental microadenomas, test characteristics, pharmacological and surgical treatment outcomes, patient's quality of life, discounting, and the costs of hormone testing, bromocriptine, MRIs, hospitalization for surgery, and physician services. PRL screening, endocrine screening panel, and MRI follow-up all provided slightly greater quality-adjusted survival than expectant management, but the costs increased disproportionately more than the benefits. The incremental cost per quality-adjusted life year for PRL screening is $1,428, and that for the endocrine screening panel is $69,495. These results are most sensitive to patient anxiety about the microadenoma; increased anxiety shifts the recommended strategy to the endocrine screening panel. We conclude that in patients with an incidental asymptomatic pituitary microadenoma, a single PRL test may be the most cost-effective management strategy. PMID- 9360518 TI - Effects of propylthiouracil and methimazole on fetal thyroid status in mothers with Graves' hyperthyroidism. AB - Thionamide therapy is a mainstay of the treatment of hyperthyroidism complicated by pregnancy, but it can expose the fetus to hypothyroidism. In terms of fetal thyroid status, propylthiouracil (PTU) has been preferred over methimazole (MMI) based on experimental data on limited transplacental passage, and lower doses have been recommended. However, neither of these practices is supported by convincing clinical evidence. We compared the effect of maternal ingestion of PTU with that of MMI on fetal thyroid status using cord sera at delivery in 77 mothers with Graves' hyperthyroidism who were receiving thionamides and whose free T4 (FT4) levels were within the normal range. We also examined the dose effects on fetal thyroid status in these women. Thirty-four women were taking PTU (group P), and 43 were taking MMI (group M). Neither the mean fetal FT4 nor the mean fetal TSH level was significantly different between the two groups. No significant difference in the occurrence of low FT4 levels or high fetal TSH levels was found between group P and group M (low FT4, 6% vs. 7%; high TSH, 21% vs. 14%). Little relationship was observed between maternal doses and fetal thyroid status; in fact, when low doses of both PTU (100 mg daily or less) and MMI (10 mg daily or less) were administered, high TSH levels in the fetus were observed in 7 of the 34 fetuses (21%) and in 6 of the 43 fetuses (14%), respectively. Higher doses were associated with normal or low fetal TSH levels. These findings demonstrate that in terms of fetal hypothyroidism-inducing potential, there is little reason to choose PTU over MMI. Individualized, not uniformly low, doses of these drugs may prevent fetal hypothyroidism. PMID- 9360519 TI - Prognosis and treatment of brain metastases in thyroid carcinoma. AB - We analyzed 47 cases of brain metastases from thyroid cancer seen at 1 institution over 5 decades. Brain metastases were a primary clinical feature at initial presentation in 15% of the cases, were identified during the subsequent course of the disease in 68%, and were only discovered at autopsy in 23%. The primary thyroid tumor was differentiated cancer in 68%, anaplastic cancer in 23%, and medullary cancer in 9%. Patients were typically older, with frequent evidence of aggressive disease and distant metastases at initial cancer diagnosis. Once brain metastases were diagnosed, disease-specific mortality was 78%, with a median product-limit survival of 4.7 months (67% and 12.4 months, respectively, for those with differentiated cancer). Resection of one or more foci of brain metastases significantly improved survival. The median disease-specific survival from diagnosis of brain metastases was 16.7 months for patients who underwent local excision of one or more brain metastases, compared with 3.4 months for those who did not (P < 0.05), independent of the presence of multifocal brain lesions. Recombinant human TSH safely stimulated radioiodine uptake for treatment of brain metastases in 1 patient. However, no evidence of survival benefit was found from radioiodine therapy, external beam radiotherapy, or chemotherapy. In summary, brain metastases from thyroid carcinoma are an extremely poor prognostic sign. Although selection bias and other unidentified factors inherent to retrospective analysis limit this conclusion, surgical resection of brain metastases may be associated with prolonged survival in differentiated carcinoma. PMID- 9360520 TI - Autosomal dominant neurohypophyseal diabetes insipidus associated with a missense mutation encoding Gly23-->Val in neurophysin II. AB - Autosomal dominant neurohypophyseal diabetes insipidus (ADNDI) is an inherited disease caused by progressive degeneration of the magnocellular neurons of the hypothalamus leading to decreased ability to produce the hormone arginine vasopressin (AVP). Affected individuals are not symptomatic at birth, but usually develop diabetes insipidus at 1-6 yr of age. The genetic locus of the disease is the AVP-neurophysin II (NPII) gene, and mutations that cause ADNDI have been found in both the signal peptide of the prepro-AVP-NPII precursor and within NPII itself. An affected girl who presented at 9 months of age and her similarly affected younger brother and father were all found to have a novel missense mutation (G1758-->T) encoding the amino acid substitution Gly23-->Val within NPII. The mutation was confirmed by restriction endonuclease analysis. A T1 weighted magnetic resonance imaging of the father's pituitary gland demonstrates an attenuated posterior pituitary bright spot. This mutation may be valuable for developing models of dominantly inherited neurodegeneration, as the early age of onset of symptoms suggests that this mutation may be particularly deleterious to the magnocellular neuron. PMID- 9360521 TI - Effects of weight change on plasma leptin concentrations and energy expenditure. AB - Circulating concentrations of leptin are closely correlated with body fat mass, and may thus constitute an afferent limb of a system regulating body fatness, with efferent limbs that affect energy expenditure and food intake. We studied 50 subjects (27 males, 23 premenopausal females; 31 never-obese, 19 obese) at usual body weight during active weight loss or weight gain and during the maintenance of body weights 10% above usual (WT + 10%) and 10% and/or 20% below usual body weight (Wt -10% and Wt -20%) to test the hypotheses that the dynamic process of weight change and the maintenance of an altered body weight are associated with significant changes in circulating concentrations of leptin and/or the relationship between fat mass and leptin, and such changes in the plasma concentration of leptin are related to changes in energy expenditure at altered body weight. Subjects were admitted to the Rockefeller University Hospital, and energy metabolism (24-h energy expenditure, resting energy expenditure, thermic effect of feeding, and nonresting energy expenditure) and circulating concentrations of leptin and insulin were examined at various weight plateaus (usual body weight, 10% above usual body weight, 10% below usual body weight, and 20% below usual body weight). Plasma leptin was also measured in some subjects during dynamic periods of weight gain or loss. Though both plasma leptin concentrations and fat mass were significantly correlated with resting energy expenditure, only the correlation of fat mass and energy expenditure remained significant in a multiple stepwise linear regression analysis. Neither absolute nor relative changes in plasma leptin between weight plateaus were significantly correlated with any of the observed changes in energy expenditure. Plasma leptin concentrations were significantly lower during weight loss than during weight maintenance at the same body composition. Plasma leptin concentrations, normalized to fat mass, were significantly lower during the maintenance of a reduced body weight in females and higher during the maintenance of an elevated body weight in males than in the same subjects at usual body weight. At all weight plateaus, plasma leptin concentrations normalized to fat mass were significantly higher in females than in males, but gender was not a significant covariate of the relationship between leptin and energy expenditure. Postabsorptive serum concentrations of insulin was a significant covariate of plasma leptin concentration in males, but not females, at Wt initial and Wt + 10%. Although plasma leptin is significantly reduced during dynamic weight loss compared with static weight maintenance at the same body weight, the lack of correlation between changes in plasma leptin and changes in energy expenditure between weight plateaus suggests that leptin is not the primary signal that mediates the changes of energy expenditure that accompany the maintenance of an altered body weight in humans. PMID- 9360522 TI - Thyrotropin-receptor and thyroid peroxidase-specific T cell clones and their cytokine profile in autoimmune thyroid disease. AB - We studied the cytokine profile and the immune responses to thyroid antigens of specific T cell clones (TCC) isolated from patients with Hashimoto's thyroiditis (HT) and Graves' disease (GD). Antigen-specific TCC were reactive to thyroid peroxidase (TPO), thyroglobulin (Tg) or human recombinant TSH-receptor extracellular domain (TSH-R), and/or their respective peptides. Of the 43 clones derived from HT patients, 65% were reactive to TPO, and 59% of the 32 clones derived from GD patients were reactive to TSH-R. TPO epitopes 100-119 and 625-644 were recognized by 75% of HT-derived clones, whereas TSH-R epitopes 158-176, 207 222, and 343-362/357-376 were recognized by 85% of GD-derived TCC. The TCC were classified according to their cytokine profile into T helper cell (Th)0 [secreting interleukin (IL)-4, IL-5, interferon (IFN)-gamma], Th1 (secreting IFN gamma) and Th2 (secreting IL-4 and/or IL-5). Tumor necrosis factor-beta and IL-10 were produced by all subsets. The specific TCC were predominantly Th1-like cells in HT, and were Th0- and Th1-like cells in GD. Fifty three percent of Th0 clones were derived from GD patients and were reactive to TSH-R, whereas 50% of Th1 clones were derived from HT patients and were reactive to TPO or Tg. Most Th2 clones (82%) were reactive to TPO and were established from peripheral blood. All these clones produced IL-5, and 64% produced IL-4 and IL-10. Interestingly, IFN gamma was highly produced by TPO- or Tg-specific clones established from HT thyroid tissue. These results confirm at the clonal level our previous studies regarding T cell epitopes on TPO and TSH-R molecules and support the concept that immunodominant T cell epitopes are located on amino acid residues 100-119 and 625 644 of TPO in HT and amino acid residues 158-176, 207-222 and 343-362/357-376 of TSH-R in GD. Our studies also demonstrate that thyroid-specific T cells can be classified into Th0, Th1, and Th2 subsets. TPO- or Tg-specific clones with Th1 phenotype appear to be involved in the pathogenesis of HT, mediating thyroid tissue destruction, whereas TSH-R clones with Th0 phenotype may induce thyroid stimulating autoantibodies in GD. PMID- 9360523 TI - A bioactive 60-kilodalton prolactin species is preferentially secreted in cultures of mitogen-stimulated and nonstimulated peripheral blood mononuclear cells from subjects with systemic lupus erythematosus. AB - We have evaluated the production of PRL by human peripheral mononuclear cells (PBMNC) from normal subjects and patients with systemic lupus erythematosus (SLE). Conditioned medium prepared from basal and Con-A-stimulated PBMNC was assessed for the presence of PRL-like by its ability to stimulate growth of PRL responsive Nb2 rat lymphoma cells. In the presence or absence of Con-A, SLE PBMNC secrete significantly higher (P < 0.001) amounts of bioactive PRL-like species than normal cells. Growth of Nb2 cells by conditioned medium was inhibited with specific antiserum to human PRL. Western blotting using a polyclonal antibody to human PRL revealed a single 60-kDa PRL-like species in both normal and SLE PBMNC extracts, the immunoreactivity of which was preferentially found in SLE subjects. With the use of reverse transcription-PCR an expected 633-bp band was observed, and its similarity to pituitary PRL was further confirmed by Southern blot analysis with human PRL complementary DNA as a probe. We conclude that a high molecular mass PRL-like species is synthesized and secreted by PBMNC, and patients with SLE have an increased secretion of lymphocyte-derived PRL-like material. PMID- 9360524 TI - In familial hyperaldosteronism type I, hybrid gene-induced aldosterone production dominates that induced by wild-type genes. AB - We compared the aldosterone-producing potency of the angiotensin II-sensitive wild-type aldosterone synthase genes and the ACTH-sensitive hybrid 11 beta hydroxylase/aldosterone synthase gene by examining aldosterone, PRA, and cortisol day-curves (2-hourly levels over 24 h) in patients with familial hyperaldosteronism type I, before and during long-term (0.8-13.5 yr) glucocorticoid treatment. In 8 untreated patients, PRA levels were usually suppressed, and aldosterone correlated strongly with cortisol (r = 0.69-0.99). Fourteen studies were performed on 10 patients receiving glucocorticoid treatment that corrected hypertension, hypokalemia, and PRA suppression in all. ACTH was markedly and continuously suppressed in 6 studies, 3 of which demonstrated strong correlations between aldosterone and PRA (r = 0.77-0.92). ACTH was only partially suppressed in the remaining 8 studies; aldosterone correlated strongly: 1) with cortisol alone in 5 (r = 0.71-0.98); 2) with cortisol (r = 0.90) and PRA (r = 0.74) in one; 3) with PRA only in one (r = 0.80); and 4) with neither PRA nor cortisol in one. Unless ACTH is markedly and continuously suppressed, aldosterone is more responsive to ACTH than to renin/angiotensin II, despite the latter being unsuppressed. This is consistent with the hybrid gene being more powerfully expressed than the wild-type aldosterone synthase genes in familial hyperaldosteronism type I. PMID- 9360525 TI - Spontaneous thyrotropin and cortisol secretion interactions in patients with nonclassical 21-hydroxylase deficiency and control children. AB - Both exogenous and endogenous hypercortisolism result in reduced TSH secretion and mild hypothyroidism. However, little is known about the relation between endogenous TSH and cortisol secretion under physiological or slightly disturbed conditions. To examine this, we evaluated the pulsatility and circadian rhythmicity and time-cross-correlated the 24-h secretory patterns of cortisol and TSH in eight prepubertal children with nonclassical congenital adrenal hyperplasia (NCCAH) and eight age-matched short normal children. In both groups, TSH and cortisol were secreted in a pulsatile and circadian fashion, with a clear nocturnal TSH surge. Although no difference in mean 24-h TSH levels was observed between the two groups, daytime TSH levels were lower in the NCCAH group than in control children (P < 0.05). The cross-correlation analysis of the 24-h raw data showed that TSH and cortisol were negatively correlated, with a 2.5-h lag time for both groups, with cortisol leading TSH. This correlation might reflect a negative glucocorticoid effect exerted on the hypothalamic-pituitary-thyroid axis under physiological conditions. A significant positive correlation with TSH leading cortisol was observed at 8.5 and 5.5 h lag times for the control and NCCAH groups, respectively. The substantially shorter lag time of this positive correlation in NCCAH children than in controls suggests that in the latter, the nocturnal TSH peak occurs temporally closer to their compromised morning cortisol peak. These data indicate that the hypothalamic-pituitary-adrenal axis has a primarily negative influence on endogenous TSH secretion and that even mild disturbances in cortisol biosynthesis are associated with slight alterations in TSH secretion. PMID- 9360526 TI - Frequent loss of heterozygosity on chromosomes 3p and 17p without VHL or p53 mutations suggests involvement of unidentified tumor suppressor genes in follicular thyroid carcinoma. AB - Follicular thyroid carcinoma (FTC) exhibits frequent loss of heterozygosity (LOH) on chromosomes 10q and 3p, suggesting involvement of tumor suppressor genes. We screened 14 FTC (10 Hurthle cell carcinomas and 4 nonoxyphilic FTC), 14 papillary thyroid carcinomas, and 7 follicular adenomas for LOH on chromosome arms 1p, 3p, 3q, 10p, 10q, 11p, 11q, 13q, 17p, and 17q. LOH was more frequent in FTC than in follicular adenoma or papillary thyroid carcinoma. In FTC, rates of LOH on 3p (86%), 17p (72%), and 10q (57%) were higher than the average rate of LOH (33%; P < 0.05). Most frequently involved were 3p21-25 and 17p13.1-13.3, the sites for the VHL (3p25-26) and p53 (17p13.1) tumor suppressors. We, therefore, characterized these genes by dideoxy fingerprinting and DNA sequencing. Two FTC had mutations in p53, but only 1 of these exhibited LOH at 17p. No VHL gene mutations were found. Thus, neither p53 nor VHL genes play a significant role in the pathogenesis of differentiated thyroid cancer. LOH on 17p, but not on 3p or 10q, was correlated with mortality. Accordingly, 3p and 10q LOH may represent early, and 17p LOH late, events in FTC development. The data suggest the presence of novel tumor suppressor genes on chromosomes 3p and 17p that may be important in the pathogenesis of FTC. PMID- 9360527 TI - Coexpression and cross-regulation of the prolactin receptor and sex steroid hormone receptors in breast cancer. AB - The sex steroid hormones and PRL interact synergistically to control the neoplastic growth of the mammary gland. The basis for this hormonal synergy is unknown, but may involve cellular coexpression of the sex steroid and PRL receptors, coupled with receptor cross-regulation. To examine this hypothesis the expression of the sex steroid and PRL receptors was examined in 20 human breast cancer cell lines and 123 primary breast cancers. Regulation of sex steroid receptors by PRL and of the PRL receptor by sex steroids was examined in T-47D and MCF-7 breast cancer cells. Northern analysis of the breast cancer cell lines and tumors indicated that the PRL receptor and the sex steroid receptors were coexpressed. The level of PRL receptor expression in the breast cancer cell lines was linearly related to that of the estrogen and progesterone receptors, but not to that of the androgen receptor. In MCF-7 and T-47D cells, acute treatment with progestins and androgens and long term treatment with estrogens increased PRL receptor levels. Analysis of sex steroid receptor messenger ribonucleic acid and binding activity showed that acute PRL treatment produced a time- and concentration-dependent increase in progesterone receptor and a decrease in androgen receptor. These results indicate that receptors for sex steroids and PRL are coexpressed and are cross-regulated, providing a potential mechanism for the observed synergy among estrogen, progesterone, and PRL in the control of tumor growth. PMID- 9360528 TI - Thyrotropin levels during hydrocortisone infusions that mimic fasting-induced cortisol elevations: a clinical research center study. AB - Both short term fasting and administration of high doses of glucocorticoids lead to marked suppression of serum TSH levels in healthy subjects. However, it is not known whether the more mild serum cortisol elevations seen during fasting can account for fasting-induced TSH suppression. To study this question, eight healthy subjects each underwent three 2-day studies: 1) baseline (adlibitum diet), 2) fasting (56 h of total caloric deprivation), 3) hydrocortisone (HC) infusions at a dose and pulsatile pattern that reproduced cortisol levels measured during each subject's fasting study. Subjects required 34-46 mg HC/24 h to achieve these cortisol levels. During each study, blood samples were drawn every 15 min during the final 24 h for serum cortisol and TSH levels. A TRH stimulation test was performed at the end of each study. By design, fasting and HC infusions induced similar mild increases in 24-h serum cortisol levels (32% over baseline), with the most significant increases seen between 1400-0200 h. Fasting decreased 24-h mean and pulsatile TSH levels 65% from baseline, whereas HC infusions decreased mean and pulsatile TSH levels 51% from baseline. Daytime (0800-0200 h) TSH levels were identical in the two studies, whereas nocturnal (0200-0800 h) TSH levels during HC infusions fell midway between baseline and fasting studies. Serum total T3 and TSH responses to TRH were decreased to a similar degree by fasting or HC infusions. These results suggest that mild elevations in endogenous cortisol levels may mediate at least in part fasting induced changes in TSH secretion and thyroid hormone levels. In addition, these data show that near-physiological doses of HC and resulting changes in serum cortisol levels within the normal range can cause significant decreases in serum TSH levels. PMID- 9360529 TI - Novel compound heterozygous mutations of growth hormone (GH) receptor gene in a patient with GH insensitivity syndrome. AB - A girl with severe growth retardation had the clinical features of Laron syndrome. Her serum insulin-like growth factor-I level was completely unresponsive to exogenous GH administration. The serum GH-binding protein (GHBP) level was below the detectable limit in the patient, but it was normal in her parents and brother. Her parents and brother were normal in their height. Amplification with PCR and direct sequencing of her GH receptor gene revealed compound heterozygous mutations. The allele from her mother contained a transversion of G to T in exon 7 that could introduce a stop codon in place of a glutamic acid at amino acid 224. Another mutation was found in the allele in her father and also identified in her brother. It was a C deletion at position 981 in exon 10 that could introduce a frame shift, thereby causing the production of 20 novel amino acids (310-329) instead of the wild-type sequence, the premature termination at codon 330, and the subsequent deletion of the C terminal portion of the intracellular domain. RT-PCR of her father's lymphocytes and sequencing of its complementary DNA revealed that only the wild-type GH receptor messenger RNA was expressed in his lymphocytes, though the mechanism remains unclear. These results suggest that neither of the mutant alleles could generate a functional GH receptor, which would be consistent with the patient's severe growth retardation and undetectable serum GHBP. PMID- 9360530 TI - Short-term modulation of the androgen milieu alters pulsatile, but not exercise- or growth hormone (GH)-releasing hormone-stimulated GH secretion in healthy men: impact of gonadal steroid and GH secretory changes on metabolic outcomes. AB - Gonadal steroids are known to alter GH secretion as well as tissue metabolism. The present study was designed to examine the effects of short term (2- to 3 week) alterations in gonadal steroids on basal pulsatile (nonstimulated) and exercise- and GH-releasing hormone-stimulated GH secretion, urinary nitrogen excretion, and basal and exercise-stimulated oxygen consumption. Two protocols were conducted, which reflect a total of 18 separate studies. In the first paradigm, 5 healthy young men were each studied in a double blind, randomized manner during 3 different gonadal hormone manipulations, in which serum testosterone was varied from hypogonadal (induced by leuprolide) to eugonadal (saline injections) to high levels (testosterone enanthate, 3 mg/kg.week, i.m.). There was a washout period of 8 weeks between treatments. In the second protocol, 3 of the original subjects were studied after 2 weeks of treatment with stanozolol (0.1 mg/kg.day). Two to 3 weeks after the desired changes in serum testosterone, each subject was admitted to the General Clinical Research Center for study. The hypogonadal state (serum testosterone, 33 ng/dL) increased urinary nitrogen loss (by 34%; P < 0.005) and decreased basal metabolic rate (by 12%; P < 0.02) compared with the eugonadal state (testosterone, 796 ng/dL). High dose testosterone (1609 ng/dL) further decreased urinary nitrogen loss over the eugonadal state (by 16%; P < 0.05). Stanozolol yielded the lowest urinary nitrogen excretion of all (P < 0.03). Like urinary nitrogen, the basal metabolic rate showed the greatest change between the hypogonadal and eugonadal states (12%; P < 0.02), with a lesser change during high dose testosterone treatment (4%). Analogously, end-exercise oxygen consumption rose by 11% between the hypogonadal and eugonadal states (P < 0.05). Between the hypogonadal and eugonadal states, no significant changes in pulsatile (nonstimulated), exercise stimulated, or GRF-stimulated GH secretion or serum insulin-like growth factor I concentrations were observed. Raising testosterone to supraphysiological levels increased pulsatile GH secretion by 62% over that with leuprolide and by 22% over that with saline (P < 0.05). High dose testosterone treatment also increased serum insulin-like growth factor I concentrations by 21% and 34% over those during the eugonadal and hypogonadal states, respectively (P < 0.01). Testosterone did not affect either exercise- or GRF-stimulated GH secretion. In protocol 2, stanozolol did not affect any parameter of GH secretion. To examine the interaction between GH secretion and testosterone on urinary nitrogen excretion and basal metabolic rate, a one-way analysis of covariance was undertaken. Statistical examination of GH production as the covariate and testosterone (by tertile) as the interactive factor demonstrated significant relationships between serum testosterone levels and either urinary nitrogen (P < 0.02) or basal metabolic rate (P < 0.01), but not GH secretion (P = NS). In summary, these results demonstrate that short term modulation of the androgen milieu affects metabolic outcome without necessitating changes in GH secretion. These results have significance for both normal physiology and for the treatment of hypogonadal GH-deficient patients. PMID- 9360531 TI - Presence of activin, inhibin, and follistatin in epithelial ovarian carcinoma. AB - Activin induces proliferation in epithelial ovarian carcinoma cell lines, whereas follistatin (FS), an activin binding protein, inhibits this action. To test the hypothesis that activin production, in excess of inhibin and FS, results in cell proliferation in epithelial ovarian tumors, messenger RNA (mRNA) expression of the activin family of proteins, FS, and activin type I and II receptors was examined in 25 primary epithelial ovarian tumors and tumor epithelium in culture (n = 7) using RT-PCR. Activin A was measured in the serum of ovarian cancer patients, and activin A, total inhibin, and FS protein secretion was measured from primary epithelial tumors in vitro. The effect of activin and FS on cell proliferation was assessed by measuring [3H]thymidine incorporation. All results were compared with normal ovarian epithelium. All epithelial ovarian tumors expressed mRNA for the alpha, beta A, and beta B subunits; FS 288 and 315; and the activin type IA, IB, II, and IIB receptors. beta A mRNA expression, as assessed using semiquantitative RT-PCR, was 3-fold greater in cultured tumor epithelium than in primary tumors (band density 0.86 +/- 0.17 vs. 0.28 +/- 0.09; P < 0.01). In addition, beta A mRNA was abundantly expressed in normal epithelium in culture (n = 2), whereas only trace amounts were seen in 2/9 primary epithelial samples. Activin protein was secreted by 24/25 primary epithelial ovarian tumors (range 0.2-155.8 ng/mL). In contrast, total inhibin was secreted by only 2/25 (range 0.01-0.92 ng/mL), whereas free FS was not detectable in the medium of any tumor (< 0.5 ng/mL). Treatment with activin or FS did not consistently affect cell growth. Measurement of serum activin A in a subset of subjects and in 27 additional subjects with epithelial ovarian carcinoma (n = 33) revealed preoperative activin A levels > 3 SD above the mean for pre- and postmenopausal women in 13/33 (39%) subjects. We conclude that in epithelial ovarian cancer: 1) beta A subunit mRNA is expressed, 2) activin protein is secreted more frequently than inhibin and in greater quantities than FS, 3) beta A subunit mRNA expression is greater in neoplastic and normal epithelium in culture than in the primary tissue, 4) the majority of tumors in culture do not respond to activin or FS treatment with proliferation, and 5) serum activin levels may reflect tumor secretion in some patients. Thus, activin A appears to be available as an autocrine/paracrine factor in epithelial ovarian tumors and may contribute to circulating levels, but its role in tumorigenesis has yet to be defined. PMID- 9360532 TI - Inappropriate gonadotropin secretion in polycystic ovary syndrome: influence of adiposity. AB - In recent years, there has been uncertainty concerning the association of inappropriate gonadotropin secretion (high LH and normal FSH) and the polycystic ovary syndrome (PCOS). In the present study, we ascertained the influence of body composition on LH pulsatile parameters in 33 PCOS and 32 normal cycling (NC) women across a wide range of body mass index (BMI, 19-42 kg/m2). Twenty four-hour pulsatile parameters for serum LH (10-min sampling) and pituitary gonadotropin responses to i.v. bolus GnRH (10 micrograms) were evaluated. Fasting (0800 h) FSH and steroid hormone concentrations and 24-h mean insulin levels were determined. Insulin sensitivity (SI) was assessed by rapid i.v. glucose tolerance test in a subset of 28 PCOS and 29 NC subjects. Our results showed that BMI, an indicator of relative adiposity, had a significant negative impact on 24-h mean LH pulse amplitude (r = -0.63, P < 0.001) and the peak increment of LH in response to GnRH stimulation (r = -0.41; P = 0.02) for PCOS but not NC women. In contrast, 24-h LH pulse frequency was uniformly increased (40%) in PCOS as compared with NC women independent of BMI. In PCOS women, the blunting of pulse amplitude with increasing BMI resulted in a decline in 24-h mean LH levels (r = -0.63, P < 0.001) and the ratio of LH/FSH (r = -0.44, P = 0.02) not seen in NC. With BMI < 30 kg/m2, 24-h mean LH values for PCOS women were greater than the normal range for NC in 95% (18/19) of cases, whereas 24-h LH levels failed to discriminate PCOS from NC women in 43% (6/14) of obese (BMI > 30 kg/m2) PCOS women. Thus, the diagnostic value of LH determinations is retained for PCOS women with BMI < 30 kg/m2. For screening purposes, the mean of two LH values in samples collected at 30-min intervals was found to have a discriminatory power equal to that of the 24 h mean. These findings suggest that 1) BMI negatively influences LH pulse amplitude in PCOS women principally by an effect at the pituitary level; 2) accelerated LH pulse frequency in PCOS women is not influenced by BMI and represents a basic component of hypothalamic dysfunction in PCOS women; and 3) BMI does not influence gonadotropin secretion in normal cycling women. Thus assessments of basal LH levels and the LH/FSH ratio in hyperandrogenic anovulatory women are clinically meaningful when BMI is taken into account. Investigations to define the factor(s) that link adiposity and the attenuation of LH pulse amplitude in PCOS women would add further understanding of this complex neuroendocrine-metabolic disorder. PMID- 9360534 TI - Vascular endothelial growth factor expression is higher in differentiated thyroid cancer than in normal or benign thyroid. AB - Vascular endothelial growth factor (VEGF) is an angiogenic factor, and its expression has been rarely demonstrated in thyroid tumors. We, therefore, investigated the expression of VEGF messenger RNA (mRNA) and production of VEGF protein in cell lines from human primary and metastatic follicular (FTC-133, FTC 236, and FTC-238), papillary (TPC-1), Hurthle cell (XTC-1), and medullary thyroid cancers (MTC-1.1 and MTC-2.2), and in human thyroid tissues (papillary, follicular, medullary, and Hurthle cell cancers, follicular adenomas, and Graves' thyroid tissue) by Northern blot, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) studies. All thyroid cell lines expressed a 4.2 kilobase VEGF mRNA. The VEGF mRNA levels were higher in the thyroid cancer cell lines than in primary cultures of normal thyroid cells, and higher in thyroid cancers of follicular than those of parafollicular cell origin. The VEGF mRNA levels were similar in primary and metastatic thyroid tumors. Immunohistochemical staining and Northern blot analysis of the cell lines correlated positively, thus thyroid cancer cell lines stained more intensely than normal thyroid cells and follicular tumor cells more intensely than parafollicular tumor cells. Again, no difference was noted in VEGF staining between primary and metastatic thyroid tumors. Deparafinized sections of papillary, follicular, and Hurthle cell cancers also stained much stronger than those of medullary thyroid cancers, benign, or hyperplastic (Graves' disease) thyroid tissue. Thyroid cancer cell lines (XTC-1 > TPC-1 > FTC-133 > MTC-1.1) also secreted more VEGF protein as measured by ELISA than did normal thyroid cells. VEGF secretion of cell lines derived from primary and metastatic thyroid tumors were similar. VEGF mRNA is therefore expressed, and VEGF protein is secreted by normal, hyperplastic, and neoplastic thyroid tissues. The higher levels of VEGF expression in differentiated thyroid cancers of follicular cell origin suggests a role in oncogenesis. PMID- 9360533 TI - Abnormalities of apolipoprotein E in the acquired immunodeficiency syndrome. AB - Given the important role of apolipoprotein E (apoE) in triglyceride metabolism, we analyzed plasma levels and degree of sialylation of apoE in subjects with the acquired immunodeficiency syndrome (AIDS), a disorder accompanied by hypertriglyceridemia. Levels of apoE were significantly increased (1.84-fold) and correlated with plasma triglycerides (r = .663, P < .001) in AIDS. Subjects with AIDS and the apoE3/E2 phenotype showed the most prominent increases in both plasma triglyceride and apoE levels (3.4 and 2.2-fold over controls). Additionally, apoE from subjects with AIDS showed an increased amount of sialylation, compared with controls (34% increase in apoE3/E3 subjects). Increased sialylation correlated with the increase in apoE levels. In contrast, there was no increase in sialylation of apo C-III in AIDS. Thus, triglyceride levels in AIDS are influenced by apoE subtype and subjects with AIDS show changes in apoE structure. PMID- 9360535 TI - Ontogeny of follicle-stimulating hormone receptor gene expression in isolated human ovarian follicles. AB - FSH stimulates antral follicles to grow, but its role in earlier stages, if any, is obscure. Our aim was to determine the follicle stage at which the FSH receptor (FSHr) gene is first expressed. We used a PCR-based strategy to analyze single follicles ranging from primordial to multilaminar stages after isolation from human ovaries. Ovarian tissue was obtained from 11 women (age range, 25-33 yr) undergoing elective cesarean section. Tissue was partially disaggregated in medium containing 1% collagenase, and follicles were manually dissected free of stroma. Follicle stages were confirmed microscopically as primordial (nongrowing), primary (1 layer of cuboidal granulosa cells), or having 2 or more layers of granulosa cells. Rectus muscle and stromal tissue were used as negative controls. Messenger ribonucleic acid (mRNA) from each follicle was reverse transcribed, and the resulting cDNA was amplified by nested PCR using primers for FSHr and actin. None of the 9 primordial follicles expressed FSHr mRNA. Thirty three percent of the primary and 2-layer follicles were positive for FSHr mRNA (4 of 12 and 3 of 9, respectively), as were 100% (n = 4) of the multilaminar follicles. The difference in FSH expression between the growing and primordial follicles was significant. This study shows for the first time that transcription of the FSHr gene begins at the earliest stages of follicular growth and indicates that FSH may have a hitherto unsuspected physiological role in preantral follicle development. In addition, this study demonstrates the practical feasibility of investigating the expression of other genes during human folliculogenesis. PMID- 9360536 TI - Human thyroid peroxidase (TPO) isoforms, TPO-1 and TPO-2: analysis of protein expression in Graves' thyroid tissue. AB - Thyroid peroxidase (TPO) is the key enzyme involved in the biosynthesis of thyroid hormones and is an important autoantigen in autoimmune thyroid disease. Different messenger RNA species coding for TPO are present in thyroid tissue, including the species coding for a 933-amino acid protein (termed TPO-1) and a second in which exon 10 is deleted and which is 57 residues shorter (termed TPO 2). However, it is not known whether the smaller, TPO-2 isoform is expressed as a protein in thyroid cells. In SDS-PAGE under reducing conditions, TPO appears in the thyroid microsome and purified protein preparations as a closely migrating double band of approximately 105 (larger form) and 100 kilodaltons (smaller form). We investigated the presence of the isoform TPO-2 polypeptide in Graves' thyroid tissue using rabbit antisera to three different synthetic peptides from exon 10 (specific for TPO-1) and a polyclonal rabbit and monoclonal anti-TPO antibody (both of which are specific for the two forms of TPO). The larger and smaller forms of TPO were purified by electroelution after gel electrophoresis of highly purified natural TPO from Graves' thyroid microsomes. Both of the purified forms of TPO react with all three anti-exon 10 peptide antibodies, the polyclonal anti-TPO and the monoclonal antibody anti-TPO. This shows that both forms of TPO contain exon 10-encoded polypeptide of TPO-1. Interestingly, the proportion of the larger and smaller forms of TPO varied in different Graves' thyroid microsome preparations. To investigate the presence of the smaller TPO-2 isoform in the purified natural TPO preparation, affinity depletion of TPO-1 using the anti-exon 10 peptide antibodies was carried out. The binding of anti-exon 10 peptide antibodies to the immunodepleted TPO-1 fraction was considerably diminished in comparison to binding of polyclonal anti-TPO, suggesting the presence of small amounts (< 10%) of TPO-2 expressed as a protein in thyroid cells. Our results extend previous observations by showing that the alternatively spliced form of TPO, in which exon 10 is excised, is expressed at low levels in Graves' thyroid tissue. Furthermore, we confirm that both the larger and smaller forms of TPO observed on gel electrophoresis contain TPO-1, suggesting that the difference is caused by posttranslational modifications. The presence of small amounts of TPO-2 in Graves' thyroid glands argues for its role in thyroid function, which remains to be clarified. PMID- 9360537 TI - Corticosteroid-binding globulin synthesis regulation by cytokines and glucocorticoids in human hepatoblastoma-derived (HepG2) cells. AB - Plasma corticosteroid-binding globulin (CBG) concentrations decrease dramatically in patients with septic shock or burn injury. This decrease suggests that mediators of the acute phase response, such as cytokines and glucocorticoid hormones, might influence clearance as well as liver synthesis of CBG in humans. The present study investigated the effects of interleukin-6 (IL-6), IL-1 beta, and dexamethasone on CBG synthesis by a clone of human hepatoblastoma-derived (HepG2) cell line. In culture medium from HepG2 cells, the immunoconcentration of CBG and the levels of CBG messenger ribonucleic acid (mRNA) were dose dependently decreased in the presence of IL-6 concentrations ranging from 0.1-10 ng/mL. The percent decrease in CBG immunoconcentration was quantitatively similar to the percent decrease in CBG mRNA levels (29 +/- 6% and 39 +/- 15%, respectively, of control values). In contrast, and as expected, IL-6 dose dependently increased the mRNA levels (164 +/- 22% of control values) of alpha 1-antitrypsin, a positive acute phase protein, but did not affect the immunoconcentration of sex hormone-binding globulin, another liver protein. Dexamethasone alone did not significantly affect CBG secretion or mRNA levels, but did dose-dependently increase tyrosine amino-transferase mRNA levels, which increased to 252 +/- 16% of the control values. However, in combination with IL-6, dexamethasone had a significant additive effect on IL-6 inhibition of CBG secretion and mRNAs in HepG2 cells. IL-1 beta dose-dependently stimulated CBG secretion (156 +/- 10% of control values) with no significant effect on CBG mRNA levels. In addition, IL-1 beta significantly decreased the inhibitory effect of IL-6 on CBG secretion, but had no effect on the inhibitory effect of IL-6 on CBG mRNA levels. These results suggest that IL-1 beta acts on the posttranslation processing and/or secretion mechanisms of CBG in HepG2 cells. Together, the present results strongly support the hypothesis that the decrease in plasma CBG concentrations is associated with the increase in IL-6 and glucocorticoid levels reported in patients with septic shock and burn injury. PMID- 9360538 TI - Relationship between melatonin rhythms and visual loss in the blind. AB - Melatonin rhythms were assessed in 49 registered blind individuals by measurement of the urinary metabolite of melatonin, 6-sulfatoxymelatonin (aMT6s). Subjects had different causes of visual loss and were classified as having light perception or better (LP; n = 19) or having no perception of light (NPL; n = 30). Subjects collected four-hourly urine samples (eight-hourly overnight) for 48 h at weekly intervals for 3-5 weeks. The majority of LP subjects (14 of 19) had normally entrained aMT6s rhythms (mean acrophase range, 2.4-6.2 h), 4 were abnormally entrained to 24 h (mean acrophase range, 8.9-1.0 h), and 1 was unclassified. Conversely, most NPL subjects had abnormal rhythms (23 of 30), the incidence of which was greater in uni- and bilaterally enucleated subjects. The majority of NPL subjects (17 of 30) had free-running aMT6s rhythms period range, 24.13-24.79 h), 5 were abnormally entrained to 24 h (acrophase range, 7.2-20.6 h), and 1 was unclassified. Output (micrograms of aMT6s per 24 h) and amplitude (micrograms per h) of aMT6s production did not vary between LP and NPL subjects (mean 24-h output +/- SD, 12.7 +/- 7.5 and 9.4 +/- 6.4 micrograms aMT6s/24 h, respectively; mean amplitude +/- SD, 0.6 +/- 0.4 and 0.5 +/- 0.3 microgram/h, respectively). These results indicate that a higher proportion of NPL subjects have abnormal melatonin rhythms compared to those with LP. PMID- 9360539 TI - Expression of somatostatin receptor SST4 in human placenta and absence of octreotide effect on human placental growth hormone concentration during pregnancy. AB - In pregnancy, the human placenta GH acts as a growth-promoting hormone and appears to be the main stimulator of insulin-like growth factor I (IGF-I) secretion. In a woman with a TSH-secreting macroadenoma, successful treatment with the somatostatin analog octreotide was conducted during the first month and the second half of pregnancy without side-effects on placental and fetal development. As observed in normal pregnancy, both serum placental GH and IGF-I levels increased throughout pregnancy and dropped sharply after delivery. In placental membranes from both treated and healthy untreated patients, we demonstrated the presence of high affinity binding sites for somatostatin-14 (Kd, 4.6 and 5.3 nmol/L; binding capacity, 1.53 and 1.35 pmol/mg protein, respectively). These receptors displayed low affinity for octreotide (IC50, 1.2-2 mumol/L), suggesting the presence of SST1 and/or SST4 receptors. We found that messenger ribonucleic acids of these two subtypes were expressed in both human placental tissue and purified human cytotrophoblast cells. Finally, the SST1 selective analog, des-AA1,2,5[D-Trp8,IAmp9]S-14 had low affinity for placental somatostatin receptors. These results argue in favor of the presence of the SST4 subtype in human placenta. At the doses administered, octreotide did not bind to placental somatostatin receptors. Our results may explain the absence of changes in both human placental GH and IGF-I concentrations that we observed during octreotide treatment. PMID- 9360540 TI - Long polyglutamine tracts in the androgen receptor are associated with reduced trans-activation, impaired sperm production, and male infertility. AB - The X-linked androgen receptor (AR) gene contains two polymorphic trinucleotide repeat segments that code for polyglutamine and polyglycine tracts in the N terminal trans-activation domain of the AR protein. Changes in the lengths of these polymorphic repeat segments have been associated with increased risk of prostate cancer, an androgen-dependent tumor. Expansion of the polyglutamine tract causes a rare neuromuscular disease, spinal bulbar muscular atrophy, that is associated with low virilization, reduced sperm production, testicular atrophy, and infertility. As spermatogenesis is exquisitely androgen dependent, it is plausible that changes in these two repeat segments could have a role in some cases of male infertility associated with impaired spermatogenesis. To test this hypothesis, we examined the lengths of the polyglutamine and polyglycine repeats in 153 patients with defective sperm production and compared them to 72 normal controls of proven fertility. There was no significant association between the polyglycine tract and infertility. However, patients with 28 or more glutamines (Gln) in their AR had more than 4-fold (95% confidence interval, 4.9 3.2) increased risk of impaired spermatogenesis, and the more severe the spermatogenic defect, the higher the proportion of patients with a longer Gln repeat. Concordantly, the risk of defective spermatogenesis was halved when the polyglutamine tract was short (< or = 23 Gln). Whole cell transfection experiments using AR constructs harboring 15, 20, and 31 Gln repeats and a luciferase reporter gene with an androgen response element promoter confirmed an inverse relationship between Gln number and trans-regulatory activity. Immunoblot analyses indicated that the reduced androgenicity of the AR was unlikely to be due to a change in AR protein content. The data indicate a direct relation between length of the AR polyglutamine tract and the risk of defective spermatogenesis that is attributable to the decreased functional competence of AR with longer glutamine tracts. PMID- 9360541 TI - Effect of variations in plasma magnesium concentration on resistance to insulin mediated glucose disposal in nondiabetic subjects. AB - Eighteen nondiabetic volunteers were selected for these studies on the basis of their plasma magnesium (Mg) concentrations defined as being either high (> 0.83 mmol/L) or low (< 0.80 mmol/L). Although different in Mg concentration (0.90 +/- 0.02 vs. 0.73 +/- 0.01 mmol/L), the 2 groups were comparable in terms of age, gender distribution, body mass index, and waist to hip girth. Measurements were made of their plasma glucose and insulin concentrations in response to a 75-g oral glucose load and the steady state plasma insulin and glucose (SSPG) concentrations at the end of an 180-min infusion of octreotide, insulin, and glucose. The low Mg group had significantly higher plasma glucose (P < 0.001) and insulin (P < 0.002) concentrations after the oral glucose challenge. Although the steady state plasma insulin concentrations were similar during the infusion study, the SSPG concentration was significantly (P < 0.001) greater in the low Mg group (11.9 +/- 0.9 vs. 6.6 +/- 0.9 mmol/L). Finally, when the 18 patients were analyzed together, there were significant (P < 0.05 to P < 0.01) inverse correlations between Mg concentrations and glucose (r = -0.68) and insulin (r = 0.51) areas and SSPG concentrations (r = -0.60). Thus, a low Mg concentration in nondiabetic subjects was associated with relative insulin resistance, glucose intolerance, and hyperinsulinemia. PMID- 9360542 TI - Elevated nonesterified fatty acid concentrations in severe preeclampsia shift the isoelectric characteristics of plasma albumin. AB - We previously hypothesized that the endothelial cell dysfunction observed in women with preeclampsia might be caused by an imbalance between circulating very low density lipoproteins and a cytoprotective pI 5.6 isoform of albumin, referred to as toxicity preventing albumin (TxPA). An accurate simplified method was developed to quantify TxPA in small volumes of pregnancy plasma by gel electrofocusing. This assay revealed that circulating TxPA concentrations in women with severe preeclampsia were significantly reduced compared to those in normal pregnant women and women with benign transient hypertension of pregnancy. Nonesterified fatty acids (NEFA) and triglycerides were elevated in plasma from women with severe preeclampsia compared to those in plasma from the two control groups. The inverse correlation between TxPA and NEFA values led us to analyze the NEFA bound to plasma albumin. Gas chromatography and mass spectrometry demonstrated no qualitative differences in the specific fatty acids bound to plasma albumin in severe preeclamptic and normal pregnant women. However, the quantity of NEFA bound to albumin was greater in preeclampsia plasma (2.5 mol NEFA/mol albumin) compared to that in normal pregnancy plasma (0.8 mol NEFA/mol albumin), accounting for the acidic pI shift observed in albumin from the former patients. Functional assays demonstrated that human very low density lipoprotein particles were toxic to human umbilical vein endothelial cells in vitro, but this toxicity was prevented by the addition of TxPA albumin to the culture medium. PMID- 9360543 TI - Outcomes of long-term testosterone replacement in older hypogonadal males: a retrospective analysis. AB - To determine the complications, toxicities, and compliance of long term testosterone replacement in hypogonadal males, we retrospectively assessed 45 elderly hypogonadal men receiving testosterone replacement therapy and 27 hypogonadal men taking testosterone. Hypogonadism was defined as a bioavailable testosterone serum concentration of 72 ng/dL or less. Both groups received baseline physical examinations and blood tests. The testosterone-treated group received 200 mg testosterone enanthate or cypionate im every 2 weeks, and follow up examinations and blood samplings were performed every 3 months. The control group had a single follow-up blood test and physical examination. There was no significant difference in the initial blood tests in the two groups. At 2 yr follow-up, only the hematocrit showed a statistically significant increase in the testosterone-treated group compared to the control group (P < 0.001). A decrease in the urea nitrogen to creatinine ratio and an increase in the prostate-specific antigen concentration was not statistically significant. Eleven (24%) of the testosterone-treated subjects developed polycythemia sufficient to require phlebotomy or the temporary withholding of testosterone, one third of which occurred less than 1 yr after starting testosterone treatment. There was no significant difference in the incidence of new illness in the two groups during the 2-yr follow-up. Although self-assessment of libido was dramatically improved in the testosterone-treated group (P < 0.0001), approximately one third of the subjects discontinued therapy. In conclusion, testosterone replacement therapy appears to be well tolerated by over 84% of the subjects. Long term testosterone replacement to date appears to be a safe and effective means of treating hypogonadal elderly males, provided that frequent follow-up blood tests and examinations are performed. PMID- 9360545 TI - A single amino acid substitution in the putative redox partner-binding site of P450c17 as cause of isolated 17,20-lyase deficiency. AB - The molecular basis of isolated 17,20-lyase deficiency was clarified in a newborn male patient from Israel with micropenis, undescended testes, and hormonal pattern consistent with isolated 17,20-lyase deficiency. Analysis of the CYP17 gene revealed the presence of a compound heterozygosity. One allele carries a single base pair deletion (T at position 198 in exon 1) leading to a frame shift with the introduction of a premature stop codon, TGA, at residue 74 in place of Val. The other allele bears a missense mutation due to a single base change, T to G, which substitutes Phe417 with Cys. The proof of heterozygosity was possible via amplification and direct sequencing of genomic DNA fragments from the parents and the healthy brother of the index case. We could demonstrate that the mother is the carrier of the nonsense mutation and the father of the missense mutation. The brother carries two normal alleles for the CYP17 gene. The nonsense mutation gives no functional product. The missense mutation causes the synthesis of a protein that retains 17 alpha-hydroxylase activity but virtually no 17,20-lyase activity. Experiments based on the use of an electron donor independent from enzyme binding (iodosobenzene) demonstrated that the addition of electrons restores, at least in part, in vitro 17,20-lyase activity, with no significant influence on the 17 alpha-hydroxylase activity. This suggests that the electron transfer system plays a major role in the differential regulation of the two P450c17 activities. This is the first case of mutated CYP17 in which the in vitro model corresponds to the in vivo situation. PMID- 9360544 TI - Gene expression of endothelin-1, endothelin-converting enzyme-1, and endothelin receptors in human epididymis. AB - We have previously reported the presence of endothelin-1 (ET-1) and its receptors in the human testis. In the present study we extended our investigations to human epididymis. The rationale of our study originated from the fact that sperm appear to be immotile during their transit through the epididymis. Hence, it is conceivable that specific factors, unknown to date, are present in this organ, capable of inducing smooth muscle contractions, thus forcing sperm transport. In this paper it is shown that ET-1 messenger ribonucleic acid and protein are readily detectable in the epithelial compartment of the human epididymis, and that ET-converting enzyme-1, which converts the precursor pro-ET-1 into the active peptide ET-1, is expressed in the epididymis, thus indicating an active processing of the prohormone. In addition, two classes of ET receptors were characterized and located in the muscle cells of the epididymis. These receptors correspond, in terms of affinity constants and capacity, to the ETA and ETB receptors previously characterized. These receptors mediate the contractile activity of the epididymis in vitro, thus suggesting that ET-1 can be responsible of sperm progression through this organ, acting via a paracrine mode of action. PMID- 9360546 TI - A membrane-fixed, truncated isoform of the human growth hormone receptor. AB - Previously, we reported the identification of a new human GH receptor (hGHR) messenger RNA species that encodes a smaller hGHR isoform, termed hGHRtr. Its messenger RNA is expressed in several human tissues and predicts a severely truncated GHR protein that lacks 97.5% of the intracellular domain. Because these two hGHR isoforms, which display similar binding affinity, are coexpressed in several tissues, they may reside side by side and, therefore, interrelate. To further characterize the biological properties of hGHRtr in comparison with hGHR, we generated Chinese hamster ovary (CHO) cell lines stably expressing each of these hGHR isoforms. Cross-linking of [125I]hGH to CHO/hGHRtr cells revealed a majored specific complex with apparent Mr of approximately 100 kDa, which would indicate the hGHRtr to be in molecular mass form of about 80 kDa. When compared with CHO/hGHR, CHO/hGHRtr cells secreted higher amounts of soluble GH-binding protein (GHBP). In contrast to CHO/hGHR cells, CHO/hGHRtr cells did not exhibit any GH-induced receptor down-regulation, and internalization was markedly reduced. Analysis of the constitutive turnover of cellular hGHR and soluble GHBP showed that incubation of CHO/hGHR cells with cycloheximide caused parallel disappearance of hGHR and GHBP. This contrasted with the stability of GHRtr, which showed no decline after cycloheximide treatment for up to 4 h, suggesting that the bulk GHRtr and GHBP may be derived from preformed proteins. Thus, in contrast to hGHR, hGHRtr is fixed at the cell membrane; it undergoes minimal internalization, no down-regulation by hGH, no constitutive turnover for as long as 4 h, but increased capacity to generate a soluble GHBP. Because hGHRtr failed to undergo ligand-induced internalization, the source of the continuous, undisturbed GHBP released into the medium may be from an intracellular storage pool. The relative abundance of these two hGHR isoforms, through regulation of splicing, could be of critical importance in modulating the biological effects of GH. PMID- 9360548 TI - Extraskeletal osteoclastomas responsive to dexamethasone treatment in Paget bone disease. AB - Giant cell tumors (GCTs) of bone, also called osteoclastomas, complicate Paget bone disease (PBD), though infrequently. Giant cell reparative granulomas (GCRGs), which are histologically similar to GCTs, also occur rarely in pagetic patients. A 45-yr-old black woman with neurofibromatosis, type I, and polyostotic PBD developed slowly-growing masses in the right posterior iliac and left upper parasacral regions. She had multiple cutaneous neurofibromas and cafe-au-lait spots. Serum alkaline phosphatase activity and urine hydroxyproline levels were elevated. Skeletal radiographs and bone scintigraphy showed changes of widespread PBD. Computerized tomography and magnetic resonance imaging (MRI) delineated masses in the right gluteal and the left lower lumbar paraspinal regions. Five additional smaller masses were found in the abdomen and in the pelvis. Biopsy of the right gluteal mass revealed a GCT. However, we found that this lesion had several histologic features distinct from those of giant cell reparative granulomas or GCT. In our patient's tumor, the huge polykaryons, like osteoclasts, expressed abundant tartrate-resistant acid phosphatase activity, whereas those of GCRG lack this enzyme. Although the polykaryons in conventional GCTs and GCTs in PBD express tartrate-resistant acid phosphatase activity, the location of these tumors in bone differs from the extraskeletal masses encountered in our patient. Furthermore, the larger size of the polykaryons and the greater number of nuclei in our patient's GCT differ from conventional GCTs, but not GCTs in PBD. Her extraskeletal osteoclastoma rapidly shrunk to one third its original size during 2 weeks of oral dexamethasone treatment. Significant clinical improvement lasted about 5 months before additional courses of dexamethasone therapy were necessary. Injections of synthetic salmon calcitonin alone did not affect the tumor's size. Thus, PBD can be complicated by extraskeletal tumors that seem to contain osteoclasts and are responsive to dexamethasone treatment. PMID- 9360547 TI - Analysis of immunoglobulin G kappa antithyroid peroxidase antibodies from different tissues in Hashimoto's thyroiditis. AB - Antibodies (Ab) to thyroid peroxidase (TPO) are common in patients with autoimmune thyroid disease and may play a role in disease pathogenesis. We have prepared immunoglobulin G kappa (IgG kappa) and IgG lambda phage display combinatorial libraries from the cervical (thyroid-draining) lymph nodes of 2 Hashimoto's thyroiditis patients and from the thyroid of 1 patient. After selection with purified recombinant human TPO, up to 10 high affinity IgG kappa clones from each tissue source were analyzed further. No IgG lambda Fab were detected in the patient with the highest TPO Ab titer. Sequence analysis of the clones showed restricted heavy and light chain usage, similar to that in previously published TPO-reactive Fabs. This was despite the substantially larger sizes of the initial libraries, the use of lymph node tissue to generate libraries, and the analysis of the repertoire in patients with Hashimoto's thyroiditis rather than Graves' disease. There was overall similarity in sequences obtained from lymph node and thyroid libraries, with higher levels of somatic hypermutation in the former. The Fab inhibited binding of serum TPO Ab from five patients by 55-95%. These data together with those from previous reports indicate that although there is no unique Ab gene usage, there is the recurrent presence of certain variable regions in the high affinity TPO Ab response. PMID- 9360549 TI - Three novel mutations and a de novo deletion mutation of the DAX-1 gene in patients with X-linked adrenal hypoplasia congenita. AB - The DAX-1 [DSS (dosage sensitive sex)-AHC critical region on the X, gene 1] gene is responsible for X-linked adrenal hypoplasia congenita (AHC). However, DAX-1 protein structure-function relationships are not well understood. Identification of missense mutations may help to reveal these relationships. We analyzed the DAX 1 gene from seven patients in six kindreds with X-linked AHC and identified one frameshift mutation, two missense mutations, and three deletion mutations. Case 1 had a 388delAG frameshift mutation, inducing a premature stop codon at position 70. Case 2 had a missense mutation, Lys382Asn, which encodes an asparagine (Asn) for lysine (Lys) at position 382. Sibling cases of 3-1 and 3-2 had a missense mutation of Trp291 Cys, which encodes a substitution of cysteine (Cys) for tryptophan (Try) at position 291. The tryptophan (Trp) at position 291 and lysine (Lys) at position 382 in human DAX-1 protein are highly conserved among other related orphan nuclear receptor superfamily members. Cases 4, 5, and 6 showed deletion mutation. In case 6, a de novo deletion mutation was revealed by both southern hybridization and polymerase chain reaction (PCR) of a GGAA tetranucleotide tandem repeat. These findings suggest that: 1) Trp at position 291 and Lys at position 382, located in the C-terminal presumptive ligand binding domain, are important to the functional role of the DAX-1 protein in adrenal embryogenesis and/or in hypothalamic-pituitary activity; and 2) molecular analysis of the DAX-1 gene may help genetic counseling, even in cases with deletion mutation, because a detection of de novo deletion may exclude another affected or carrier child. PMID- 9360550 TI - Urocortin expression in human pituitary gland and pituitary adenoma. AB - Urocortin is a recently identified neuropeptide of the CRF family in the mammalian brain, but its expression in human tissue has been little studied. In this study, we examined urocortin expression in human anterior pituitary gland and pituitary adenomas by RIA, high performance liquid chromatography, immunohistochemistry, messenger ribonucleic acid (mRNA) in situ hybridization, and reverse transcriptase-PCR. Immunoreactive urocortin concentrations in normal pituitary tissue extract were 103.25 +/- 39.05 ng/g wet wt (mean +/- SEM; n = 4), and their levels were all significantly higher than those in other portions of central nervous system of the same subjects. High performance liquid chromatography analysis of human pituitary extract demonstrated a single peak corresponding to that of the expected chromatographic mobility of synthetic human urocortin-(1-40). Urocortin-immunoreactive cells were detected in the anterior pituitary gland. Neither urocortin-immunoreactive nerve fibers nor cells were detected in the posterior lobe. Immunostaining in serial mirror tissue sections revealed that 76.55 +/- 3.06% of urocortin-immunoreactive cells expressed GH immunoreactivity, whereas 22.25 +/- 3.02% and less than 1% of urocortin immunoreactive cells expressed PRL and ACTH, respectively. mRNA hybridization signals of urocortin were also detected in urocortin-immunopositive pituitary cells. The reverse transcriptase-PCR analysis demonstrated a 145-bp RNA band corresponding to that of the expected length of urocortin in all cases of normal pituitary glands examined (n = 3). We also immunostained urocortin in 52 cases of human anterior pituitary adenomas, including GH-producing adenomas (n = 14), ACTH producing adenomas (n = 13), PRL-producing adenomas (n = 11), and nonfunctioning hormonally inactive adenomas (n = 14). No urocortin immunoreactivity was detected in these adenoma cells, except for one case of GH-producing adenoma and one case of nonfunctioning adenoma. We also performed mRNA in situ hybridization in 27 adenomas. No hybridization signals were detected in these adenomas, except in two cases. The results described above indicated that urocortin is synthesized in human anterior pituitary cells and may play an important role in biological features of normal pituitary gland, possibly as an autocrine or a paracrine regulator PMID- 9360551 TI - Expression and localization of activin subunits and follistatins in tissues from men with high grade prostate cancer. AB - Activins are growth and differentiation factors that have growth inhibitory effects on LNCaP and DU145, but not PC3, human prostate tumor cell lines. Activin binding proteins, follistatins, block the inhibitory actions of exogenously added activins on LNCaP and DU145 tumor cell lines. Based on these in vitro observations using human prostate tumor cell lines, the aims of this study were to determine whether activins and follistatins are expressed in the human prostate in tissues from men with high grade prostate cancer. The expression and cellular localization of these proteins in malignant and nonmalignant regions of these tissues were compared to determine whether any changes occur with progression to malignancy. The results demonstrate that activins and follistatins are synthesized in tissues from men with high grade prostate cancer, and that messenger ribonucleic acid (mRNA) and protein for the activin beta A- and beta B subunits and follistatin is expressed and localized to poorly differentiated tumor cells. In the nonmalignant regions, activin beta A and beta B subunit mRNA and proteins are predominantly localized to the epithelium. Follistatin mRNA was expressed in the basal epithelial cells and in the fibroblastic stroma; however, the localization of follistatin proteins using two specific antisera demonstrated a difference between the follistatin isoforms expressed in basal cells and the stroma. In the progression to malignancy, the colocalization of follistatin and activins to the tumor cells in vivo implies that resistance to the growth inhibitory effects of activin may be conferred by follistatins. PMID- 9360552 TI - Colocalization of 11 beta-hydroxysteroid dehydrogenase type II and mineralocorticoid receptor in human epithelia. AB - The enzyme 11 beta-hydroxysteroid dehydrogenase type II (11 beta HSD2) has been shown to confer specificity on mineralocorticoid receptors (MR) by inactivating glucocorticoids. In the present study we examined the colocalization of 11 beta HSD2 and MR in various exocrine and secretory glands by immunostaining of serial mirror tissue sections with subsequent computerized image analysis. Both 11 beta HSD2 and MR proteins were expressed in the same cells in the distal convoluted tubules, Henle's loop, and collecting tubules of the kidney and the absorptive epithelia of duodenum, jejunum, ileum, colon, and excretory ducts of anal and esophageal glands. Significantly, 11 beta HSD2 and MR immunoreactivity also colocalized in the respiratory tract, in collecting ducts of the tracheal and bronchial glands, ciliated bronchial epithelial cells, and type II alveolar epithelial cells, suggesting important and unexpected roles for mineralocorticoids in the lung. In the skin, 11 beta HSD2 and MR were present only in excretory ducts of eccrine sweat glands, but not in sebaceous or apocrine glands. In eccrine glands, MR immunoreactivity was present in the basal cells of excretory ducts, while 11 beta HSD2 immunoreactivity was localized in the luminal cells. Neither 11 beta HSD2 nor MR proteins were expressed in the lacrimal gland, prostate, bile ducts, gall bladder, urinary bladder, urethra, or ureter. These results indicate that 11 beta HSD2 protein colocalizes with MR protein in the great majority of sodium-transporting epithelia involved in serous secretion and supports the proposal that 11 beta HSD2 is a pivotal determinant of mineralocorticoid receptor occupancy in man. Furthermore, our demonstration of colocalization in discrete areas of the lung suggests that mineralocorticoid agonists or antagonists, and/or inhibitors of 11 beta HSD2, may have unexpected applications in respiratory disease. PMID- 9360553 TI - Substantial production of dopamine in the human gastrointestinal tract. AB - Considerable urinary excretion of dopamine metabolites indicates that large amounts of dopamine are produced in unknown locations of the body. This study assessed the contribution of mesenteric organs (gastrointestinal tract, spleen, and pancreas) to the total body production of dopamine in humans and examined the presence of the rate-limiting enzyme for dopamine synthesis, tyrosine hydroxylase, in gastrointestinal tissues. Blood sampled from an artery and portal and hepatic veins in eight subjects and from arterial and renal venous sites in other subjects was analyzed for plasma concentrations of dopamine and its metabolites. The activity and distribution of tyrosine hydroxylase was also examined in tissue samples from the stomach and duodenum. Higher concentrations of dopamine and its metabolites in portal venous than arterial plasma indicated substantial production of dopamine by mesenteric organs (12.0 nmol/min) amounting to 42-46% of the renal removal of circulating dopamine metabolites. Tissue samples showed immunoreactive tyrosine hydroxylase in nonneuronal cell bodies and detectable levels of tyrosine hydroxylase in nonneuronal cell bodies and detectable levels of tyrosine hydroxylase enzyme activity. The results show that mesenteric organs produce close to half of the dopamine formed in the body, most of which is unlikely to be derived from sympathetic nerves but may reflect production in a novel nonneuronal dopaminergic system. PMID- 9360554 TI - Cell type-specific expression of 17 beta-hydroxysteroid dehydrogenase type 2 in human placenta and fetal liver. AB - The enzymatic actions of the 17 beta-hydroxysteroid dehydrogenase (17 beta HSD) isozymes are crucial in steroid hormone metabolism/physiology. The type 1 isozyme catalyzes the conversion of the biologically inactive C18 steroid, estrone, to the active estrogen, 17 beta-estradiol, and the enzyme is predominantly expressed in the syncytiotrophoblast of the placenta and the granulosa cells of the ovary. 17 beta HSD type 2 is highly expressed in placenta, liver, and secretory endometrium and catalyzes the conversion of bioactive estrogens and androgens to biologically inactive 17-ketosteroid counterparts. The expression pattern of 17 beta HSD type 2 protein was determined in human term placenta and fetal liver by immunohistochemical analysis using monoclonal antibodies directed against distinct epitopes of the 17 beta HSD type 2 protein. In placenta, the protein was detected in the endothelial cells of fetal capillaries, but not in cytotrophoblasts or syncytiotrophoblast. There was dichotomous immunostaining seen among pairs of cotyledonary vessels and chorionic vessels. In the liver, on the other hand, staining was detected in the hepatocytes, but not in the cells lining blood vessels. We conclude that the cell type-specific localization of 17 beta HSD type 2 is in accord with the proposed physiological role of the enzyme, namely to protect tissues, in this case the fetus, from bioactive estrogen and androgen. PMID- 9360555 TI - Sporadic congenital hyperthyroidism due to a spontaneous germline mutation in the thyrotropin receptor gene. AB - Neonatal hyperthyroidism in the absence of maternal autoimmune thyroid disease and without thyroid-stimulating antibodies in the child is rare. We here describe a boy with severe intrauterine hyperthyroidism and advanced bone age in the absence of thyroid-stimulating autoantibodies. After long term antithyroid treatment and relapse of hyperthyroidism, a near-total thyroid resection was performed. The necessity to progressively decrease postoperative thyroid hormone replacement indicates thyroid tissue regrowth in the small thyroid remnant. Analysis of the genomic DNA of the child's peripheral leukocytes showed a G to A base exchange that led to a heterozygous Ser to Asn conversion at position 505 in the third transmembrane region of the TSH receptor (TSHR). The absence of the Ser505 Asn mutation in all other family members identifies the child's TSHR mutation as a sporadic germline mutation. Transient expression of the mutated TSH receptor in COS-7 cells showed a constitutively activated cAMP cascade. We thus identified a new constitutively activating germline mutation. Neonates with persistent nonautoimmune hyperthyroidism should be investigated for TSHR germline mutations. Because of frequent relapses, patients with sporadic congenital nonautoimmune hyperthyroidism should be treated with early subtotal to near-total thyroid resection. Moreover, post-operative radioiodine treatment should be considered. PMID- 9360556 TI - Somatic mutations in the thyrotropin receptor gene and not in the Gs alpha protein gene in 31 toxic thyroid nodules. AB - Studies on frequency and distribution pattern of TSH receptor (TSHR) and Gs alpha protein (gsp) mutations in toxic thyroid nodules (TTNs) reported conflicting results, most likely also related to the different screening methods applied and the investigation of only part of exon 10 of the TSHR. Therefore, we screened a consecutive series of 31 TTNs for both TSHR and gsp mutations by direct sequencing of exon 9 and the entire exon 10 of the TSHR gene and exons 7-10 of the gsp gene. Somatic TSHR mutations were identified in 15 of 31 TTNs. TSHR mutations were localized in the third intracellular loop (Asp619Gly and Ala623Val), the sixth transmembrane segment (Phe631Leu and Thr632Ile, Asp633Glu) and the second extracellular loop (Ile568Thr). One mutation was found in the extracellular TSHR domain (Ser281Asn). Two new TSHR mutations were identified. One involves codon 656 in the third extracellular loop (Val656Phe). The other new mutation is a 27-bp deletion in the third intracellular loop resulting in deletion of 9 amino acids at codons 613-621. Transient expression of the new TSHR mutations in COS-7 cells demonstrated their constitutive activity. No mutation was found in exons 7-10 of the gsp gene. This finding was confirmed by an allele specific PCR for mutations in gsp codons 201 (Arg-->His, Cys) and 227 (Gln-->His, Arg). Our data indicate that constitutively activating TSHR mutations can be found in 48% of TTNs and thus currently represent the most frequent molecular mechanism known in the etiopathogenesis of TTNs. Moreover, the absence of gsp mutations in our series argues for an only minor role of these mutations in TTNs. Constitutive activation of the TSHR by a deletion in a region that might be involved in G protein coupling of the TSHR offers new insights into TSHR activation. PMID- 9360557 TI - A novel nonsense mutation in the first zinc finger of the vitamin D receptor causing hereditary 1,25-dihydroxyvitamin D3-resistant rickets. AB - Hereditary 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]-resistant rickets (HVDRR) is a rare autosomal recessive disorder resulting in target organ resistance to the active form of vitamin D [1,25-(OH)2D3]. Point mutations in the vitamin D receptor (VDR) gene have been identified in HVDRR. We investigated the molecular basis of HVDRR in a Brazilian family with two affected siblings. The propositus is a 12-yr-old boy born to first cousin parents who exhibited the classical pattern of the HVDRR, including early-onset rickets, total alopecia, convulsions, hypocalcemia, secondary hyperparathyroidism, and elevated 1,25-(OH)2D3 serum levels. His younger sister also developed clinical and biochemical features of HVDRR at 1 month of age and died at 4 yr of age. Genomic DNA was isolated from peripheral blood of the boy and from dried umbilical cord tissue of his affected sister. We amplified exons 2 and 3 of the VDR gene, which encode the zinc finger DNA-binding domain by PCR. Direct sequencing of the PCR products revealed a homozygous substitution of cytosine for thymine at nucleotide position 88 in exon 2 of the VDR gene in both affected siblings. This point mutation determined the substitution of a stop codon (TGA) for arginine (CGA) at amino acid position 30 at the first zinc finger of the DNA-binding domain of the VDR. This substitution generated a truncated receptor missing 397 residues. The parents and a normal sister were heterozygous for this mutation. In conclusion, we describe a novel nonsense mutation in the first zinc finger of the VDR that generated a severely truncated form of this receptor. PMID- 9360558 TI - Dexamethasone, OB gene, and leptin in humans; effect of exogenous hyperinsulinemia. AB - This study was undertaken to investigate temporal association between dexamethasone administration, OB gene expression, and leptin response in humans in the presence and absence of exogenous hyperinsulinemia. Six healthy males (age 24.5 +/- 1.0 yr, body mass index 26.4 +/- 1.0, body fat 16.2 +/- 1.8%) received 10 mg oral dexamethasone in five divided doses twice (protocols A and B) 1-2 weeks apart beginning at 0800 h on day 1 and ending at 0700 h on day 2. The dexamethasone administration was combined with two subcutaneous abdominal fat biopsies performed at 0800 h before and after dexamethasone administration (protocol A), or 4-h isoglycemic hyperinsulinemic (300 mU/m2 BSA/min, protocol B) clamp carried out between 0900 and 1300 h on day 2. OB gene expression (protocol A) did not change. In both protocols on day 2, the 0800 h leptin levels nearly doubled (P < 0.001), whereas 1300 h levels nearly quadrupled (P < 0.001). The elevation in leptin persisted until 0800 h of day 3 (24 h after last dexamethasone dose) with its subsequent rapid normalization. The short-term isoglycemic hyperinsulinemia (protocol B) had no additional effect on the postdexamethasone leptin response. We summarize that: 1) 24-h administration of dexamethasone has a marked stimulatory effect on circulating leptin levels but not on OB gene expression in the subcutaneous abdominal fat. 2) The effect is sustained for the next 24 h. 3) Short-term hyperinsulinemia has no additional effect. We conclude that dexamethasone is a powerful stimulator of leptin production in vivo through a mechanism that appears to be independent of OB gene transcription in the human subcutaneous abdominal fat. PMID- 9360559 TI - Aging alters zonation in the adrenal cortex of men. AB - Whereas aging has been shown to be associated with striking reductions in circulating levels of adrenal androgens in humans, the alteration in adrenal function that occurs in aging has not been identified. We sought to determine if there are changes in the zonation of the adrenal in aging men by performing histomorphologic analyses of adrenal specimens that had been obtained at autopsy following sudden death due to trauma. We evaluated adrenals from 21 young men (20 29 yrs) and 12 older men (54-90 yrs); inclusion criteria required the presence of medullary tissue in the specimen and fixation within the first 24 hrs postmortem. Sections stained with H/E were examined microscopically and areas of the cortex that included adjacent medullary tissue were chosen for quantitative evaluation by use of a computerized image analysis system. The average width (arbitrary units, pixels) of the zona reticularis and that of the combined zonae fasciculata/glomerulosa were determined from sections stained for reticulum fibers. The zona reticularis represented 37.1 +/- 1.9% of the total cortical width in the young men, which was significantly greater than that of the older men (27.1 +/- 3.3%, P = 0.0082). The zona fasciculata/glomerulosa to zona reticularis ratio in the young men (1.84 +/- 0.15) was significantly less that that of the older men (3.29 +/- 0.47, P = 0.0011). There was no significant difference in the total width of the cortex in young compared to older men. These data suggest that aging results in alterations within the cortex of the adrenals in men such that there is a reduction in the size of the zona reticularis and a relative increase in the outer cortical zones. A reduced mass of the zona reticularis could be responsible for the diminished production of dehydroepiandrosterone and dehydroepiandrosterone sulfate that occurs during aging. PMID- 9360560 TI - Germline dinucleotide mutation in codon 883 of the RET proto-oncogene in multiple endocrine neoplasia type 2B without codon 918 mutation. AB - The autosomal dominant multiple endocrine neoplasia type 2 syndromes (MEN 2) comprise three clinically distinct entities, MEN 2A, familial medullary thyroid carcinoma and MEN 2B, which share a common clinical feature: medullary thyroid carcinoma (MTC). MEN 2B is considered to have the most aggressive form of MTC. Therefore, early detection of MEN 2B in order to prevent potentially lethal MTC is important. More than 95% of all MEN 2B cases are caused by germline mutation at codon 918 (M918T) in exon 16 of the RET proto-oncogene. In this study, we demonstrate the presence of germline codon 883 mutation (A883F) in 2 of 3 unrelated MEN 2B cases without codon 918 mutation. Our data demonstrate a novel etiologic event which may have roles in predisposition to MEN 2B when present in the germline and in the pathogenesis of sporadic MTC when somatic. PMID- 9360561 TI - Mild clinical expression of myasthenia gravis associated with autoimmune thyroid disease. PMID- 9360562 TI - Detection of an activating mutation of the thyrotropin receptor in a case of an autonomously hyperfunctioning thyroid insular carcinoma. PMID- 9360563 TI - Prediction of early complications in patients with acute myocardial infarction by calculation of the ST score. AB - STUDY OBJECTIVE: To assess the relationship between the sum of ST-segment elevations (ST score) in the admission ECG and the occurrence of early complications in patients with acute myocardial infarction (MI). METHODS: We conducted an observational study of patients who presented with acute anterior or inferior MI to the ED of a 2,000-bed inner-city hospital. Age, sex, time from onset of pain and the start of thrombolysis, and ST score were evaluated by the emergency physician. "Early complications" were defined as acute congestive heart failure or severe rhythm disturbances in the 24 hours after the start of thrombolysis. The outcome measures were the relationship between ST score and the occurrence of early complications; the influence of age, sex, or time between onset of pain and thrombolysis; and identification of a cutoff value with the highest sensitivity and specificity for prediction of complications. RESULTS: We included 243 patients (194 men, 49 women; mean age, 56.6 years) with acute MI (anterior, 119; inferior, 124) who underwent thrombolysis in our analysis. ST score was significantly greater in patients with early complications, compared with patients without complications (anterior, 10.3 versus 19.4 mm [P < .001]; inferior, 6.9 versus 10.4 mm [P < .001]). Receiver-operator curve analysis revealed an ST score of 13 mm in patients with anterior MI and 9 mm in patients with inferior MI as the cutoff value with the greatest sensitivity and specificity for predicting early complications of MI. (For anterior MI, sensitivity was .79, specificity .73; for inferior MI, sensitivity was .64 and specificity .68.). On multivariate regression analysis, ST score was an independent predictor of the occurrence of at least one complication. (For anterior MI, the odds ratio [OR] was 9.7 and the 95% confidence interval [CI] 3.9 to 25.1; for inferior MI the OR was 5.0 and the 95% CI 2.0 to 12.8). Age, sex, and interval from onset of pain to treatment had no significant effect on the occurrence of early complications. CONCLUSION: The absolute ST score is useful in estimating the probability of early complications in patients with acute MI receiving thrombolytic therapy. A cutoff value of 13 mm for anterior MI and 9 mm for inferior MI stratifies patients into high- and low-risk subgroups for the development of acute congestive heart failure and severe rhythm disturbances during the first 24 hours of hospitalization. PMID- 9360564 TI - ED use of rapid lactate to evaluate patients with acute chest pain. AB - STUDY OBJECTIVE: To test the hypothesis that ED arrival venous lactate levels can be used to diagnose acute myocardial infarction (AMI) and to identify patients with critical illness in the triage of ED patients presenting with chest pain. METHODS: This was a prospective, double-blind, clinical study in an urban, academic ED. We enrolled a convenience sample of adult patients who had chest pain or cardiac symptoms suggesting AMI that began within 24 hours of presentation. Patients underwent standard medical management for their chest pain. Venous lactate samples were analyzed in the ED on whole blood. An abnormal lactate level of 1.5 mmol/L or higher at the time of arrival was prospectively defined as indicating the presence of acute cardiac disease. ECG findings, levels of creatine phosphokinase (CK) and CK-MB, hospital stay data, and diagnosis of AMI by the cardiology admitting team were recorded. RESULTS: Of the 129 patients included in the study, 73 had an initial lactate level of 1.5 mmol/L or higher. The mean lactate level (+/- SD) for all patients was 1.8 +/- 1.2 mmol/L. A total of 28 patients (21%) were diagnosed with AMI and had a mean lactate level of 2.2 +/- .7 mmol/L, compared with 1.7 +/- 1.3 mmol/L in those patients who were not diagnosed with AMI (P < .03). The sensitivity of this lactate level in diagnosing AMI was 96% (95% confidence interval [CI], 89% to 100%), and the specificity was 55% (95% CI, 45% to 64%). The negative predictive value of blood lactate was 98% (95% CI, 95% to 100%). Lactate was elevated independent of the duration of chest pain symptoms, with a median time from onset to sampling of 3 hours. Lactate was elevated in patients who either died or required longer than 48 hours of ICU care, compared with survivors not requiring ICU care (4.5 +/- 4.3 mmol/L versus 1.4 +/- .6 mmol/L, respectively; P < .01). CONCLUSION: The blood lactate concentration obtained on ED arrival identifies those chest pain patients with critical cardiac illness (eg, AMI, severe congestive heart failure [CHF], decompensated arrhythmias). A normal blood lactate result has a high negative predictive value for AMI. An elevated lactate level used in conjunction with ECG and history distinguishes patients with significant myocardium at risk who are likely to benefit from more urgent attention and interventions by the attending physician. Additionally, hyperlactatemia clearly correlates with mortality and the need for ICU management in the acute cardiac patient presenting to the ED. PMID- 9360565 TI - Restraint position and positional asphyxia. AB - STUDY OBJECTIVE: To determine whether the "hobble" or "hog-tie" restraint position results in clinically relevant respiratory dysfunction. METHODS: This was an experimental, crossover, controlled trial at a university-based pulmonary function laboratory involving 15 healthy men ages 18 through 40 years. Subjects were excluded for a positive urine toxicology screen, body mass index (BMI) greater than 30 kg/m2, or abnormal screening pulmonary function testing (PFT). Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and maximal voluntary ventilation (MVV) were obtained with subjects in the sitting, supine, prone, and restraint positions. After a 4-minute exercise period, subjects rested in the sitting position while pulse, oxygen saturation, and arterial blood gases were monitored. The subjects repeated the exercise, then were placed in the restraint position with similar monitoring. RESULTS: There was a small, statistically significant decline in the mean FVC (from 5.31 +/- 1.01 L [101% +/- 10.5% of predicted] to 4.60 +/- .84 L [88% +/- 8.8% of predicted]), mean FEV1 (from 4.31 +/- .53 L [103% +/- 8.4%] to 3.70 +/- .45 L [89% +/- 7.7%]), and mean MVV (from 165.5 +/- 24.5 L/minute [111% +/- 17.3%] to 131.1 +/- 20.7 L/minute [88% +/- 16.6%]), comparing sitting with restraint position (all, P < .001). There was no evidence of hypoxia (mean oxygen tension [PO2] less than 95 mm Hg or co-oximetry less than 96%) in either position. The mean carbon dioxide tension (PCO2) for both groups was not different after 15 minutes of rest in the sitting versus the restraint position. There was no significant difference in heart rate recovery or oxygen saturation as measured by co-oximetry and pulse oximetry. CONCLUSION: In our study population of healthy subjects, the restraint position resulted in a restrictive pulmonary function pattern but did not result in clinically relevant changes in oxygenation or ventilation. PMID- 9360567 TI - Intoxicated ED patients: a 5-year follow-up of morbidity and mortality. AB - STUDY OBJECTIVES: To determine the rates of alcohol-related morbidity and mortality in a cohort of intoxicated ED patients 5 years after presentation and to compare them with those of non-intoxicated ED patients. METHODS: The study group comprised 150 consecutive ED patients who presented with intoxication (blood alcohol level higher than 100 mg/dL) in June 1986 and 50 control patients matched for age, sex, ED arrival time, and date. The setting was an urban university hospital ED. Morbidity and mortality over a 5-year follow-up period were measured using hospital ED and admission records from all state Level I trauma centers and computerized statewide databases. RESULTS: The 5-year mortality rate among alcohol-intoxicated patients was 2.4 times that of the comparison group (95% confidence interval, .3 to 18.9). The 5-year death rate among intoxicated patients aged 40 to 69 years was especially high (19%). Thirty seven percent of the intoxicated patients made at least one alcohol-related ED revisit during the follow-up period, compared with 6% of the comparison group (P < .001). Intoxicated patients were more likely to revisit EDs because of suicidal behavior or domestic violence (P = .001). Admission to an alcohol detoxification unit during the follow-up period occurred in 24% of the intoxicated patients, compared with 10% of the sober controls (P = .03). At least one arrest for drunk driving occurred in 47% of the intoxicated group; the rate was lower, but still substantial, in the comparison group (20%, P < .001). CONCLUSION: A single alcohol-related ED visit is an important predictor of continued problem drinking, alcohol-impaired driving and, possibly, premature death. PMID- 9360566 TI - Prevention of gastrointestinal iron absorption by chelation from an orally administered premixed deferoxamine/charcoal slurry. AB - STUDY OBJECTIVE: To investigate the effect of an orally administered premixed slurry of deferoxamine mesylate (DFO) and activated charcoal (AC) on the gastrointestinal (GI) absorption of ferrous sulfate under physiologic conditions. METHODS: This was a prospective, crossover, controlled human volunteer study. Participants were healthy adult subjects aged 25 to 38 years. Volunteers ingested either 5 mg/kg ferrous sulfate alone, 5 mg/kg ferrous sulfate added to 25 g of 20% (weight/ volume) AC, or 5 mg/kg ferrous sulfate added to a premixed slurry consisting of 8 g of DFO and 25 g of 20% (weight/volume) AC. The same group of volunteers was used in each limb of the study. Serum iron concentrations were measured at baseline and at 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, and 24 hours after ingestion for all subjects. Urinary iron was determined over the first 12 hours after ingestion for each limb. The maximum iron concentration (Cmax), the time to maximum iron concentration (Tmax), and the area under the curve (AUC) were compared for all three limbs. RESULTS: The AUC (P = .042) and Cmax (P = .017) were significantly lower in all subjects in the DFO/AC limb compared with the two control limbs. There was no significant difference in the Tmax iron concentration (P = .77). In the ferrous sulfate control limb, female volunteers had a significantly higher mean Cmax (P = .008) and AUC (P = .014) than males. Iron was undetectable in all baseline and 12-hour urine collections. CONCLUSION: In this model, a premixed 1:3 (weight/weight) DFO/ AC slurry reduced the GI absorption of ferrous sulfate in adult volunteers under physiologic conditions. PMID- 9360568 TI - Injuries caused by hazardous materials accidents. AB - STUDY OBJECTIVE: To describe exposures that prehospital and ED personnel may encounter as a result of hazardous material incidents. METHODS: Retrospective analysis of hazardous material incident reports from six district hazardous material teams in Massachusetts from their inception through May 1996. RESULTS: The chemicals most frequently involved were various hydrocarbons and corrosive materials. Chlorine derivatives were involved in 18% of all incidents and 23% of all incidents resulting in victims. Victims were produced by 47 of 162 (29%) incidents. Respiratory exposures were the most frequent type of exposure and resulted in the largest number of victims transported to a hospital. Overall 24 of 26 (92%) incidents with chemical exposures resulted in symptomatic victims and 33 of 35 (94%) incidents produced victims requiring hospital transport. Respiratory symptoms were the most frequent, both in the number of incidents where they were observed and the total number of victims with symptoms. CONCLUSION: Multiple victim transport to EDs from a single hazardous material incident is most likely to result from an inhalation exposure to a respiratory irritant. Information from descriptive studies should allow improved preparation for potential hazardous material victims. PMID- 9360569 TI - Regional intravenous infusion of calcium gluconate for hydrofluoric acid burns of the upper extremity. AB - STUDY OBJECTIVE: To describe regional intravenous infusion of calcium gluconate as a therapy for hydrofluoric acid (HF) burns of the forearm, hand, or digits. METHODS: This study describes seven patients with HF burns. Calcium gluconate, 10 mL of 10% solution with 30 to 40 mL normal saline solution, was injected intravenously into the affected limb using a Bier block technique. Ischemia was maintained for 20 to 25 minutes. Therapy was considered successful if significant reduction of pain and tenderness was noted after tourniquet release. RESULTS: Seven patients were treated. HF concentration varied from 5% to 49%. Exposure sites included the forearm (two cases), thenar eminence and digits (two cases), or digits only (three cases). Complete pain resolution occurred on tourniquet release in four patients (two with burns to the forearm, two with burns to digits only). One patient had partial relief (thenar but not digital exposure site), and two had no relief of symptoms. Intraarterial calcium gluconate perfusion was subsequently administered to the three patients with persistent subungual and pulp, or thenar pain. Recovery was complete in all cases. No adverse effects were noted. CONCLUSION: Regional intravenous infusion of calcium gluconate should be considered a therapeutic option in HF burns of the forearm, hand, or digits when topical therapy fails. PMID- 9360570 TI - Confirmation of the pulse oximetry gap in carbon monoxide poisoning. AB - STUDY OBJECTIVES: To demonstrate the degree to which pulse oximetry overestimates actual oxyhemoglobin (O2Hb) saturation in patients with carbon monoxide (CO) poisoning. This phenomenon has been reported in fewer than 20 humans in the English medical literature. METHODS: A retrospective chart review of 191 patients evaluated for CO poisoning at a regional hyperbaric center identified 124 patients 10 years of age and older who had had both arterial blood gas and pulse oximetry measurements and who had received either high-flow oxygen through a nonrebreather mask or 100% inspired oxygen through an endotracheal tube. Blood gas measurements, including direct spectrophotometric determination of O2Hb and carboxyhemoglobin (COHb) saturation values, were compared with finger-probe pulse oximetry readings. RESULTS: Measured O2Hb saturation (mean +/- SD, 88.7 +/- 10.2%; range, 51.4% to 99.0%) decreased linearly and predictably with rising COHb levels (10.7 +/- 10.4%; range, .2% to 46.4%). Pulse oximetry saturation (99.2% +/ 1.3%; range, 92% to 100%) remained elevated across the range of COHb levels and failed to detect decreased O2Hb saturation. The pulse oximetry gap, defined as the difference between pulse oximetry saturation and actual O2Hb saturation (10.5% +/- 9.7%; range, 0% to 40.6%), approximated the COHb level. CONCLUSION: There is a linear decline in O2Hb saturation as COHb saturation increases. This decline is not detected by pulse oximetry, which therefore overestimates O2Hb saturation in patients with increased COHb levels. The pulse oximetry gap increases with higher levels of COHb and approximates the COHb level. In patients with possible CO poisoning, pulse oximetry must be considered unreliable and interpreted with caution until the COHb level has been measured. PMID- 9360571 TI - Rapid life-threatening hyperkalemia after addition of amiloride HCl/hydrochlorothiazide to angiotensin-converting enzyme inhibitor therapy. AB - STUDY OBJECTIVE: To highlight the dangers of a precipitous rise in serum potassium levels in patients at risk for renal insufficiency, already receiving an angiotensin-converting enzyme (ACE) inhibitor, who are given a potassium sparing diuretic. METHODS: We conducted a retrospective chart review of five patients who were taking the above combination of medications who were seen in our ED with hyperkalemia. RESULTS: All five patients had diabetes and were older than 50 years of age. Except for one patient, they had some degree of renal impairment and all were receiving an ACE inhibitor. Each had amiloride HCl/hydrochlorothiazide added to their therapeutic regimen 8 to 18 days before presenting to our ED with hyperkalemia. Potassium levels were between 9.4 and 11 mEq/L in 4 of the patients; 2 did not respond to resuscitation measures. CONCLUSION: The concomitant use of ACE inhibitor and potassium-sparing diuretic therapy should be avoided. If impossible, weekly monitoring of both renal function and serum potassium should be performed. In the ED patients who are receiving such a combination should receive immediate ECG monitoring. PMID- 9360572 TI - Abbreviated educational session improves cranial computed tomography scan interpretations by emergency physicians. AB - STUDY OBJECTIVE: Previously published research (phase I) demonstrated a concerning misinterpretation rate of cranial computed tomography (CT) scans by emergency physicians. This study (phase II) determined whether an abbreviated educational session would improve emergency physician interpretation skills of cranial CT scans. METHODS: Participants in this prospective, interventional study in a county hospital ED were patients undergoing cranial CT scanning during ED evaluations and attending level emergency physicians. An abbreviated educational session on cranial CT interpretation skills was given to the same attending emergency physicians who participated in phase I. The educational session included basic CT interpretation skills and misinterpreted CT scans from phase I. We determined the postsession accuracy rate of the emergency physicians on 324 ED patient CT scans. The CT interpretation accuracy rates were then compared between phase I and phase II to determine the effectiveness of the educational session. RESULTS: The radiology/ED CT scan concordance rate improved from 61.3% (kappa = .22) to 88.6% (kappa = .70; P < .0001). Potentially clinically significant CT scan misinterpretations decreased from 24.1% to 4.0% (P < .0001). Most importantly, major missed findings on CT scans decreased from 11.4% to 2.8% (P < .0001). Continuous quality improvement monitoring found no instance of clinically significant patient mismanagement. CONCLUSION: Within the limits of this study, we conclude that emergency physicians' interpretation skills of cranial CT scans may be improved using a 1-hour educational session. PMID- 9360573 TI - Tenure track in emergency medicine. AB - STUDY OBJECTIVE: Tenure was designed to guarantee academic freedom through lifelong job security. Productive research, especially in the basic sciences, is the main criterion for tenure at most institutions; therefore faculty in more clinically focused specialties may experience more difficulty obtaining tenure. We examined the relationship between academic emergency medicine and tenure. METHODS: We used a questionnaire to survey the directors of all 108 approved US emergency medicine residency programs. The surveyed population was asked whether the program was affiliated with a medical school, the number of full-time faculty, and how many faculty members were tenured or on the tenure track. Follow up mailings were sent to nonresponders. We also conducted a search of the Association of American Medical Colleges (AAMC) database to compare the number of emergency medicine faculty involved in the tenure process in other specialties. RESULTS: One hundred surveys (93%) were returned. At programs in which faculty were eligible for tenure, 9% (95% confidence interval [CI], 4% to 16%) were tenured and 27% (95% CI, 19% to 37%) were on the tenure track. Therefore only 36% of all EM faculty (95% CI, 27% to 46%) were tenured or on the tenure track. Among the 53 residency programs that offered tenure, 45% (95% CI, 32% to 60%) had no tenured faculty. At programs with academic department status, 74% of chairs were tenured, in contrast to only 32% of chiefs at institutions without academic department status (95% CI for difference of 42%, 14% to 71%). The AAMC survey revealed that about one-third as many emergency medicine faculty members were tenured compared with the other specialties. The proportion of faculty on the tenure track, however, was similar between the specialties. CONCLUSION: Most eligible emergency medicine faculty members are not tenured or on track to become tenured, and fewer emergency medicine faculty are tenured compared with the more traditional specialties. Emergency medicine may be vulnerable to being considered less academic unless its faculty members gain access to the tenure process. PMID- 9360574 TI - Evidence-based emergency medicine: integrating research into practice. PMID- 9360576 TI - The critically appraised topic: closing the evidence-transfer gap. PMID- 9360575 TI - Recombinant tissue plasminogen activator: in my community hospital ED, will early administration of rt-PA to patients with the initial diagnosis of acute ischemic stroke reduce mortality and disability? PMID- 9360577 TI - Emergency identification and treatment of acute ischemic stroke. AB - In this review we describe the pathophysiology of cerebral ischemia and its implications for potential therapy. We summarize the results of recently completed trials of acute stroke intervention and explore some of the controversy surrounding thrombolysis for acute stroke. We also introduce the key concepts of neuroprotection and its therapeutic possibilities. Finally, we discuss the delays that may occur in the emergency evaluation and management of acute ischemic stroke and suggest some methods to expedite the process. PMID- 9360578 TI - A reappraisal of mouth-to-mouth ventilation during bystander-initiated cardiopulmonary resuscitation: a statement for Healthcare Professionals from the Ventilation Working Group of the Basic Life Support and Pediatric Life Support Subcommittees, American Heart Association. PMID- 9360579 TI - Emergency physicians' roles in a clinical telemedicine network. AB - STUDY OBJECTIVE: To study the roles emergency physicians have in a clinical telemedicine network. METHODS: A descriptive analysis of telemedicine consultations conducted by emergency physicians at 1 year of operation of a private clinical telemedicine program. RESULTS: From February 1, 1995, to February 1, 1996, 190 clinical telemedicine consultations were completed. Emergency medicine constituted the most common specialty consulted, accounting for 45 (24%) of the consultations. All consultations were one-time transmissions and interactions. They ranked as follows: trauma or orthopedic care, 33 (73%); adult medical problems, 6 (13%); and pediatric medical problems, 6 (13%). Of the emergency medicine teleconsultations, 39 (87%) were categorized as emergency (completed immediately). Of the emergency medicine consultations completed, 24 (53%) patients remained in the rural community, and 21 (47%) were transferred to the tertiary care facility for additional care. The primary peripheral used for emergency medicine teleconsultations was a one-chip document camera. Forty-three (96%) of the emergency medicine teleconsultations involved radiograph interpretations. The most common radiographs reviewed were of the arm, 14 (33%); leg, 10 (23%); and cervical spine, 7 (16%). There was one minor radiograph interpretation discrepancy. Of the emergency medicine teleconsultations, 65% occurred between 7 PM and 8 AM. Of emergency medicine teleconsultations, 24% were completed on Saturdays and Sundays, with 26% of consultations being completed on Fridays. All emergency physicians involved in telemedicine consultations were surveyed concurrently for satisfaction, future use, and recommendations for improvement. CONCLUSION: The technology afforded by telemedicine allows emergency physicians to participate in telemedicine consultations. Emergency physicians should consider using clinical telemedicine in their practice. PMID- 9360580 TI - Evidence-based emergency medicine. PMID- 9360581 TI - Myths regarding the NINDS rt-PA Stroke Trial: setting the record straight. PMID- 9360582 TI - Telemedicine and emergency medical care: improved care delivery, or just another video game? PMID- 9360583 TI - Of iron and ancient mariners. PMID- 9360584 TI - Update on emerging infections from the Centers for Disease Control and Prevention. Influenza: ED considerations for the 1997-98 season. PMID- 9360585 TI - Direct administration of charcoal into the lung and pleural cavity. AB - We report the inadvertent administration of activated charcoal in water into the right lung and pleural cavity of a 51-year-old man being treated for a salicylate overdose. A mild chemical pneumonitis developed, as did a sterile empyema. Charcoal-stained fluid drained through a thoracostomy tube for 8 weeks. The patient was discharged in good condition but died 4 days later after taking another overdose. Direct administration of charcoal into the lungs is best prevented by radiographic confirmation of the location of the tube. Charcoal in water may cause less severe pulmonary injury than charcoal in sorbitol. PMID- 9360586 TI - Risperidone-induced neuroleptic malignant syndrome. AB - Risperidone is an antipsychotic drug used for the treatment of schizophrenia. It was expected that this atypical neuroleptic agent would not cause dystonia or neuroleptic malignant syndrome (NMS) owing to its unique mechanism of action with attenuated anti-dopaminergic activity and more potent antiserotoninergic activity. We report the case of a geriatric patient in whom signs and symptoms consistent with NMS developed after 3 weeks of risperidone therapy. The patient presented with fever, mental status changes, tremor, and rigidity. His laboratory findings were significant for increased serum creatine phosphokinase, hypernatremia, and metabolic acidosis. There have been few reported cases of risperidone-induced NMS. Health care providers should be aware of the risk of risperidone-induced NMS. PMID- 9360587 TI - Loxosceles arizonica bite associated with shock. AB - Envenomation by the brown recluse spider (Loxosceles reclusa) is associated with shock, significant hemolysis, renal insufficiency, and disseminated intravascular coagulation (DIC). Shock has never been associated with envenomation by L arizonica, a related species indigenous to Arizona, southern California, and northwestern Mexico. We report the case of a 13-year-old girl, bitten by a specimen of L arizonica (the spider was identified by an entomologist), in whom shock and a typical cutaneous lesion developed. She did not experience renal insufficiency or disseminated intravascular coagulation. Infectious causes of shock were excluded. She recovered completely with supportive care. PMID- 9360588 TI - Seizures, ventricular tachycardia, and rhabdomyolysis as a result of ingestion of venlafaxine and lamotrigine. AB - Few cases of overdoses have been described involving venlafaxine, lamotrigine, or a combination of the two agents. We describe a combined venlafaxine and lamotrigine ingestion in a patient presenting with a seizure, ventricular tachycardia, and rhabdomyolysis. We conclude that patients with overdoses that involve venlafaxine can exhibit severe cardiac effects in addition to seizures, especially if venlafaxine is combined with other agents. PMID- 9360589 TI - Insulin for beta-blocker toxicity. PMID- 9360590 TI - Ludwig's angina. PMID- 9360591 TI - What an ED doc will do for a buck: implications for survey research. PMID- 9360592 TI - Clinical course of crack cocaine body stuffers. PMID- 9360593 TI - Connecting up the cytoskeleton. PMID- 9360595 TI - As simple as can be? PMID- 9360594 TI - Iron-ic twists of fate. PMID- 9360596 TI - Neutron Laue diffraction does it faster. PMID- 9360597 TI - Prokaryotes offer hope for potassium channel structural studies. PMID- 9360598 TI - Specific recognition of HIV-1 TAR RNA by a D-Tat peptide. PMID- 9360599 TI - Cavity formation before stable hydrogen bonding in the folding of a beta-clam protein. AB - The time course of folding of a small beta-sheet protein reveals formation of a central ligand binding cavity before the consolidation of the native hydrogen bonding network. These results suggest that side chain interactions and not stable hydrogen bonding determine the beta-sheet architecture and play crucial roles in the overall chain topology. PMID- 9360600 TI - Crystal structure of DNA photolyase from Anacystis nidulans. AB - The crystal structure at 1.8 A resolution of 8-HDF type photolyase from A. nidulans shows a backbone structure similar to that of MTHF type E. coli photolyase but reveals a completely different binding site for the light harvesting cofactor. PMID- 9360601 TI - A novel RNA-binding motif in influenza A virus non-structural protein 1. AB - The solution NMR structure of the RNA-binding domain from influenza virus non structural protein 1 exhibits a novel dimeric six-helical protein fold. Distributions of basic residues and conserved salt bridges of dimeric NS1(1-73) suggest that the face containing antiparallel helices 2 and 2' forms a novel arginine-rich nucleic acid binding motif. PMID- 9360602 TI - Crystal structure of the unique RNA-binding domain of the influenza virus NS1 protein. AB - The nonstructural protein (NS1 protein) of the influenza A virus binds to several types of RNAs. X-ray crystallographic analysis of the RNA-binding domain reveals a unique topology for the monomer as well as a novel six-helix structure for the dimer. PMID- 9360603 TI - C-terminal domain of transcription cofactor PC4 reveals dimeric ssDNA binding site. AB - The crystal structure of human replication and transcription cofactor PC4CTD reveals a dimer with two single-stranded (ss)DNA binding channels running in opposite directions to each other. This arrangement suggests a role in establishment or maintenance of melted DNA at promoters or origins of replication. PMID- 9360604 TI - Crystal structure of estrogen sulphotransferase. AB - The structure of estrogen sulphotransferase has been solved in the presence of inactive cofactor PAP and substrate 17 beta-estradiol. This structure reveals structural similarities between cytosolic sulphotransferases and nucleotide kinases. PMID- 9360605 TI - Picture story. Agony and antagonism. PMID- 9360606 TI - Neutron Laue diffractometry with an imaging plate provides an effective data collection regime for neutron protein crystallography. AB - Neutron quasi-Laue diffraction data (2 A resolution) from tetragonal hen egg white lysozyme were collected in ten days with neutron imaging plates. The data processing Laue software, LAUEGEN, developed for X-ray Laue diffractometry, was adapted for neutron diffractometry with a cylindrical detector. The data analysis software, X-PLOR, was modified and used for the refinement of hydrogen atoms, and the positions of 960 hydrogen atoms in the protein and 157 bound water molecules, were determined. Several examples are given of the methods used to identify hydrogen atoms and water molecules. PMID- 9360607 TI - Helix packing angle preferences. AB - The distribution of interaxial angles between packed alpha-helices has been explained by a number of elegant models describing how side chains on helices can interdigitate without steric conflicts. Here I show that much of the apparent preference for particular angles is due to statistical bias and that true packing angle preferences are not well described by regular packing models. PMID- 9360608 TI - Structure of Haemophilus influenzae Fe(+3)-binding protein reveals convergent evolution within a superfamily. AB - The first crystal structure of the iron-transporter ferric ion-binding protein from Haemophilus influenzae (hFBP), at 1.6 A resolution, reveals the structural basis for iron uptake and transport required by several important bacterial pathogens. Paradoxically, although hFBP belongs to a protein superfamily which includes human transferrin, iron binding in hFBP and transferrin appears to have developed independently by convergent evolution. Structural comparison of hFBP with other prokaryotic periplasmic transport proteins and the eukaryotic transferrins suggests that these proteins are related by divergent evolution from an anion-binding common ancestor, not from an iron-binding ancestor. The iron binding site of hFBP incorporates a water and an exogenous phosphate ion as iron ligands and exhibits nearly ideal octahedral metal coordination. FBP is highly conserved, required for virulence, and is a nodal point for free iron uptake in several Gram-negative pathogenic bacteria, thus providing a potential target for broad-spectrum antibacterial drug design against human pathogens such as H. influenzae, Neisseria gonorrhoeae, and Neisseria meningitidis. PMID- 9360609 TI - Cooperativity of folding of the apomyoglobin pH 4 intermediate studied by glycine and proline mutations. AB - The apomyoglobin pH 4 folding intermediate contains the A, G, and H helices of myoglobin. Helix destabilizing mutations in the A and G helices are used to test whether the pH 4 folding intermediate of apomyoglobin folds cooperatively. Single glycine or proline mutations destabilize the intermediate substantially, showing that intrinsic helix propensities are important for stability of the intermediate. The A and G helices interact to stabilize each other, as shown by the effect of mutations in the G helix on the unfolding of the A helix, which can be monitored by tryptophan fluorescence. Wild type and the most stable mutant unfold in a two-state reaction, as shown by superposition of the unfolding curves measured by two probes (far-UV circular dichroism and Trp fluorescence), while unfolding of the less stable mutants is more complex. Cooperativity and stability of folding are linked also when stabilizing anions (sulphate, perchlorate) are used to adjust stability. PMID- 9360610 TI - Intermediates and kinetic traps in the folding of a large ribozyme revealed by circular dichroism and UV absorbance spectroscopies and catalytic activity. AB - The folding thermodynamics and kinetics for the ribozyme from Bacillus subtilis RNase P are analyzed using circular dichroism and UV absorbance spectroscopies and catalytic activity. At 37 degrees C, the addition of Mg2+ (Kd approximately 50 microM) to the unfolded state produces an intermediate state within 1 ms which contains a comparable amount of secondary structure as the native ribozyme. The subsequent transition to the native state (Kd[Mg] approximately 0.8 mM, Hill coefficient approximately 3.5) has a half-life of hundreds of seconds as measured by circular dichroism at 278 nm and by a ribozyme activity assay. Surprisingly, the formation of the native structure is accelerated strongly by the addition of a denaturant; approximately 30-fold at 4.5 M urea. Thus, the rate-limiting step entails the disruption of a considerable number of interactions. The folding of this, and presumably other large RNAs, is slow due to the structural rearrangement of kinetically trapped species. Taken together with previous submillisecond relaxation kinetics of tRNA tertiary structure, we suggest that error-free RNA folding can be on the order of milliseconds. PMID- 9360611 TI - Loop length, intramolecular diffusion and protein folding. AB - Intramolecular diffusion plays a role in protein folding as shown by kinetic experiments on two alpha-spectrin SH3 domain circular permutants (S19-P20s and N47-D48s), with different poly-glycine loop lengths. Insertion of up to 10 Gly residues does not alter the structure of the folded state nor the overall characteristics of the denatured ensemble. The apparent level of the energy barrier between the denatured and folded species increases linearly with the number of inserted glycines. This suggests that the transition state itself and/or possibly previous transient unstable intermediates are accessed with more difficulty when loop length is increased. The fact that the induced impediment is directly proportional to the number of Gly residues and not to the free energy difference in the folded state indicates that diffusion of different parts of the molecule relative to each other is taking place on going from the denatured ensemble to the transition state. Our results also suggest that transition state ensembles could be more homogenous than recently postulated. PMID- 9360612 TI - Crystal structure of the protein drug urate oxidase-inhibitor complex at 2.05 A resolution. AB - The gene coding for urate oxidase, an enzyme that catalyzes the oxidation of uric acid to allantoin, is inactivated in humans. Consequently, urate oxidase is used as a protein drug to overcome severe disorders induced by uric acid accumulation. The structure of the active homotetrameric enzyme reveals the existence of a small architectural domain that we call T-fold (for tunnelling-fold) domain. It assembles to form a perfect unusual dimeric alpha 8 beta 16 barrel. Urate oxidase may be the archetype of an expanding new family of tunnel-shaped proteins that now has three members; tetrahydropterin synthase, GTP cyclohydrolase I and urate oxidase. The structure of the active site of urate oxidase around the 8 azaxanthine inhibitor reveals an original mechanism of oxidation that does not require any ions or prosthetic groups. PMID- 9360613 TI - Structure of the profilin-poly-L-proline complex involved in morphogenesis and cytoskeletal regulation. AB - Profilin, a ubiquitous low molecular weight (13,000-15,000 M(r)) actin binding protein, regulates the formation of F-actin structures in vivo, and is localized to specific cellular regions through interaction with proline-rich sequences. Here we report the 2.2 A X-ray structure of the complex between human platelet profilin (HPP) and a decamer of L-proline (L-Pro10). The L-Pro10 peptide adopts a left-handed type II poly-L-proline helix (PPII) and binds to a highly conserved patch of aromatic amino acids on the surface of profilin. The peptide and actin binding sites reside on orthogonal surfaces, and L-Pro10 binding does not result in a conformational rearrangement of HPP. This structure suggests a mechanism for the localization of profilin and its actin-related activities to sites of actin filament assembly in vivo. PMID- 9360614 TI - New diphenazines with neuronal cell protecting activity, phenazostatins A and B, produced by Streptomyces sp. AB - Phenazostatins A and B, new diphenazine compounds, were isolated from the culture broth of Streptomyces sp. 833 as new neuronal cell protecting substances which also showed free radical scavenging activity. In the cell assay, phenazostatins A and B inhibited glutamate toxicity in N18-RE-105 cells with EC50 values of 0.34 and 0.33 microM, respectively. PMID- 9360615 TI - Ampullosporin, a new peptaibol-type antibiotic from Sepedonium ampullosporum HKI 0053 with neuroleptic activity in mice. AB - Ampullosporin (I; Ac-Trp-Ala-Aib-Aib-Leu-Aib-Gln-Aib-Aib-Aib-Gln-Leu-Aib-Gln Leuol) was isolated from the mycelium of Sepedonium ampullosporum as a new 15 membered peptaibol-type antibiotic. The structure was determined by mass spectrometric and two-dimensional NMR experiments. Ampullosporin displays narrow spectrum antibacterial and antifungal activity, induces pigment formation by Phoma destructiva, causes hypothermia and decreased spontaneous locomotor activity in mice in dosages > 1 mg/kg. PMID- 9360616 TI - Antimycins, inhibitors of ATP-citrate lyase, from a Streptomyces sp. AB - A related group of compounds belonging to the antimycin class of antibiotics was found in culture broth produced by a Streptomyces species. The group includes known antimycins A1, A2, A3 and A4, and new antimycins A7 and A8. These compounds inhibit ATP-citrate lyase with Ki values of 4 to 60 microM against the substrate magnesium citrate. The structures of the new antimycins were determined by spectroscopic analyses. PMID- 9360617 TI - Thiocoraline, a new depsipeptide with antitumor activity produced by a marine Micromonospora. I. Taxonomy, fermentation, isolation, and biological activities. AB - A novel bioactive depsipeptide, thiocoraline, was isolated from the mycelial cake of a marine actinomycete strain L-13-ACM2-092. Based on morphological, cultural, physiological, and chemical characteristics, strain L-13-ACM2-092 was ascribed to the genus Micromonospora. Thiocoraline showed a potent cytotoxic activity against P-388, A-549 and MEL-28 cell lines, and also a strong antimicrobial activity against Gram-positive microorganisms. This compound binds to supercoiled DNA and inhibits RNA synthesis. PMID- 9360618 TI - Thiocoraline, a novel depsipeptide with antitumor activity produced by a marine Micromonospora. II. Physico-chemical properties and structure determination. AB - Thiocoraline (1) is a new antitumor antibiotic isolated from the mycelium of Micromonospora sp. L-13-ACM2-092. Its structure was elucidated to be a novel cyclic thiodepsipeptide on the basis of spectroscopic methods. PMID- 9360619 TI - Novel butyrolactones with antifungal activity produced by Pseudomonas aureofaciens strain 63-28. AB - The bacterium Pseudomonas aureofaciens 63-28 is antagonistic to several plant pathogenic fungi, including Pythium spp. The bacterium produced at least four antifungal metabolites active against Pythium ultimum and Phytophthora cryptogea when tested in culture for antifungal activity. Two of these compounds were identified as the novel butyrolactones (Z)-4-hydroxy-4-methyl-2-(1-hexenyl)-2 butenolide and (Z)-4-hydroxymethyl-2-(1-hexenyl)-2-butenolide, by using NMR and GC-MS. All compounds were different from other antibiotics produced by Pseudomonas spp., including pyoluteorin, pyrrolnitrin, and 2,4 diacetylphloroglucinol, as determined by HPLC. This is the first report of butyrolactones with antifungal activity produced by a saprophytic Pseudomonas spp. PMID- 9360620 TI - Microbial conversion of mevinolin. AB - About 3000 microorganisms (bacteria, Actinomyces, Zygomyces, Deuteromyces) were screened for their capacity to convert mevinolin. Absidia coerulea IDR 705 was found to produce two hydroxylated derivatives of mevinolin, 2 and 3. Compound 2 is a new transformation product while compound 3 was described as a chemical modification product of mevinolin. By combination of spectroscopic techniques, the structures of 2 and 3 were identified with beta,delta-dihydroxy-7-(1,2 dihydro-2-hydroxymethyl-6-methyl-naphthal en-1-yl)-heptanoic acid delta-lactone and beta,delta-dihydroxy-7-[1,2,3,5,6,7,8,8a-octahydro-3,5-dihydroxy-2, 6 dimethyl-8-(2-methyl-butyryloxy)-naphthalen-1-yl]-hepta noi c acid delta-lactone, respectively. The inhibitory effects of the two derivatives on the enzyme 3 hydroxy-3-methylglutaryl-coenzyme A reductase were similar to that of mevinolin. PMID- 9360621 TI - A synthetic approach to benanomicin A. 2. Synthesis of the substituted 5,6 dihydrobenzo[a]naphthacenequinone. AB - The key intermediate tri-substituted alpha-tetralone (8) has been synthesized, either via tandem Michael addition-Dieckmann condensation reaction between dienolate and methyl crotonate in a low yield or via Barton's radical decarboxylation of diester (9) without 4-dimethylaminopyridine in 75% yield, and applied to the synthesis of the substituted 5,6 dihydrobenzo[a]naphthacenequinone. PMID- 9360622 TI - Selective deoxygenation and O-methylation of benanomicin A: synthesis of 9-deoxy , 9-O-methyl- and 14-O-methylbenanomicin A. AB - The selective modifications of phenolic hydroxy groups in the chromophore of benanomicin A are described. Hydride reduction of 9-O-tosylate with sodium borohydride/nickel chloride led to 9-deoxybenanomicin A. Methylation of 1-O diphenylmethylbenanomicin A diphenylmethyl ester with sodium hydride/iodomethane gave 9-O-methyl derivative and with Hunig's base/diazotrimethylsilylmethane afforded the 14-O-methyl derivative. These compounds showed the diminished activity against fungi. PMID- 9360623 TI - Isolation and structure elucidation of novel neuronal cell protecting substances, carbazomadurins A and B produced by Actinomadura madurae. PMID- 9360624 TI - Polyozellin, a new inhibitor of prolyl endopeptidase from Polyozellus multiplex. PMID- 9360625 TI - New members of the trichothecene family. PMID- 9360626 TI - Heliquinomycin, a new inhibitor of DNA helicase, produced by Streptomyces sp. MJ929-SF2. III. Biosynthesis. PMID- 9360627 TI - Biological and mechanistic activities of phenazine antibiotics produced by culture LL-14I352. PMID- 9360628 TI - UK-1, a novel cytotoxic metabolite from Streptomyces sp. 517-02. III. Antibacterial action of demethyl UK-1. PMID- 9360629 TI - Benaphthamycin, a new dihydrobenzo[a]naphthacenequinone antibiotic from Streptomyces sp. HKI-0057. PMID- 9360631 TI - 7th International Conference on Environmental Mutagens. Toulouse, France, 7-12 September 1997. Abstracts. PMID- 9360630 TI - A novel oral carbapenem CS-834: chemical stability of pivaloyloxymethyl esters of carbapenems and cephalosporins in phosphate buffer solution. PMID- 9360632 TI - Mutation research genomics: a blending two of disciplines. PMID- 9360633 TI - Identification and characterization of two polymorphic Ya5 Alu repeats. AB - Two new polymorphic Alu elements (HS2.25 and HS4.14) belonging to the young (Ya5/8) subfamily of human-specific Alu repeats have been identified. DNA sequence analysis of both Alu repeats revealed that each Alu repeat had a long 3' oligo-dA-rich tail (41 and 52 nucleotides in length) and a low level of random mutations. HS2.25 and HS4.14 were flanked by short precise direct repeats of 8 and 14 nucleotides in length, respectively. HS2.25 was located on human chromosome 13, and HS4.14 on chromosome 1. Both Alu elements were absent from the orthologous positions within the genomes of non-human primates, and were highly polymorphic in a survey of twelve geographically diverse human groups. PMID- 9360634 TI - A nucleotide polymorphism in ERCC1 in human ovarian cancer cell lines and tumor tissues. AB - We studied the DNA sequence of the entire coding region of ERCC1 gene, in five cell lines established from human ovarian cancer (A2780, A2780/CP70, MCAS, OVCAR 3, SK-OV-3), 29 human ovarian cancer tumor tissue specimens, one human T lymphocyte cell line (H9), and non-malignant human ovary tissue (NHO). Samples were assayed by PCR-SSCP and DNA sequence analyses. A silent mutation at codon 118 (site for restriction endonuclease MaeII) in exon 4 of the gene was detected in MCAS, OVCAR-3 and SK-OV-3 cells, and NHO. This mutation was a C-->T transition, that codes for the same amino acid: asparagine. This transition converts a common codon usage (AAC) to an infrequent codon usage (AAT), whereas frequency of use is reduced two-fold. This base change was associated with a detectable band shift on SSCP analysis. For the 29 ovarian cancer specimens, the same base change was observed in 15 tumor samples and was associated with the same band shift in exon 4. Cells and tumor tissue specimens that did not contain the C-->T transition, did not show the band shift in exon 4. Our data suggest that this alteration at codon 118 within the ERCC1 gene, may exist in platinum sensitive and platinum-resistant ovarian cancer tissues. PMID- 9360635 TI - The design of a new mutation model for active genes: expression of the Escherichia coli lac operon in mammalian cells. AB - The design of a novel transgenic mouse model is described that should allow analysis of mutations at a single cell level in all tissues of a model animal. The model is based on the correct regulation of the Escherichia coli lac operon in mammalian cells. Induction of a mutation in the lacI gene will result in the loss of transcriptional repression of the lacZ gene in mutated cells. Expression of beta-galactosidase can subsequently be detected at the single cell level. The model was first tested in vitro using transfection of mouse LTK- cells. LacZ expression was very heterogeneous in most of the stable transfectants and seemed to be subject to epigenetic inactivation. One clone (IIB1) was isolated that stably expressed lacZ in more than 99% of its cells. Subsequent introduction of the lacI gene into IIB1 cells resulted in correct transcriptional repression of the lacZ gene that could be alleviated by IPTG, an allosteric inducer of lacI repression. However, in time the extent of beta-galactosidase induction gradually declined suggesting that the prolonged repressed transcriptional state triggers epigenetic inactivation. Variegated expression of the lacZ gene was not confined to cultured cells since several transgenic lines also did not express the lacZ transgene. This study shows that while the susceptibility of the lacZ gene to inactivation processes poses a fundamental problem, correct regulation of the expression of a reporter gene by the lacI repressor protein is feasible in mammalian cells when assayed at the single cell level. Thus, the model can in principle be used for the detection of mutagenic events at the lacI locus. Targeting of the lacZ gene to an endogenous housekeeping gene might prevent epigenetic inactivation. Alternatively, with the use of another reporter gene in the mutation detection system the proposed transgenic mouse model could be realized. PMID- 9360636 TI - Search for DNA sequence variations using a MutS-based technology. AB - The search for DNA sequence variations (DSV) is emphasized with genetic studies of a large number of multifactorial diseases. Saturation of regions of interest with diallelic polymorphisms will be an essential step to pinpoint, through association studies, predisposing genes. We have developed a solid-phase method based on the ability of mismatch binding protein MutS to recognize single nucleotide mismatches. This approach was applied to the study of 83 sequence tagged sites (STSs) extracted from an eight centimorgans (cM) chromosome 21 region. One-third of tested STSs were found to be polymorphic leading to a frequency of one DSV every 822 base pairs (bp). Sequencing of analyzed STSs showed the high reliability of the MutS-based technology for mismatches up to 2 bp in DNA fragments ranging in size from 200 bp to 1 kilobase (kb). The entire assay which is performed in a solid-phase format without the need of electrophoresis or sequencing, will provide an efficient tool for new polymorphism detection. PMID- 9360637 TI - Genomic analysis of single cells from human basal cell cancer using laser assisted capture microscopy. AB - In this study, we show that direct mutational analysis of genomic DNA can be performed on single somatic cells extracted from a frozen, immunohistochemically stained tissue section using laser-assisted capture microscopy. Eighty-nine single tumor cells were separately dissected from one case of human basal cell cancer (BCC) and p53 mutations were analyzed by direct semi-automated sequencing of PCR fragments. Amplification was obtained for at least one of the two analyzed exons from approximately 50% of the single tumor cells. Identical p53 mutations were found in widely spread areas of the tumor, suggesting a clonal proliferation originating from one cell. Interestingly, comparison between results of immunohistochemistry and genetic analysis of the single cells revealed the same p53 mutations irrespective of the p53 immunoreactivity. We propose that this approach has a great potential to allow investigation of genotypic differences in single cells and more specifically to resolve important and fundamental questions determining cancer heterogeneity. PMID- 9360638 TI - Apolipoprotein E R112; R251G: a carboxy-terminal variant found in patients with hyperlipidemia and coronary heart disease. AB - A 49 year-old hypercholesterolemic male with marked electrocardiographic ST segment depression on exercise testing was found to have an apo E E3/3 phenotype by isoelectric focusing, but an APOE E4/3 genotype using HhaI restriction isotyping. DNA sequence analysis of the proband's APOE gene found a G-->C point mutation at codon 251. This predicted a change in the amino acid encoded by codon 251, from arginine to glycine. The mutation occurred on an allele that encoded arginine at position 112 and this variant was named APOE R112; R251G. The R251G change altered a recognition site for the endonuclease StuI and was the basis for a restriction isotyping method to rapidly screen for this mutation. In relatives of the proband, APOE R112; R251G was consistently found in subjects with both hyperlipidemia and atherosclerosis. Apo E R112; R251G-containing very low density lipoproteins bound normally to macrophages in vitro. However, the proband had an abnormal post-prandial lipoprotein response to a dietary fat challenge. The association of APOE R112; R251G with abnormal phenotypes suggests that the amino acid change in the carboxy-terminal, perhaps in combination with the common amino acid polymorphism at codon 112, has a functional impact upon lipoprotein metabolism in members of this family. PMID- 9360639 TI - G to C transversion at a splice acceptor site causes exon skipping in the cystatin B gene. AB - Several mutations have been described in the proteinase inhibitor cystatin B gene from individuals affected with progressive myoclonus epilepsy of the Unverricht Lundborg type (EPM1). One of these mutations, a 1925G-->C transition at the 3' splice acceptor site of the intron 1, was postulated to lead to inappropriate splicing of a primary transcript of the cystatin B gene in EPM1 patients. In an effort to understand the expression of the 1925G-->C mutation, the sequence of cystatin B mRNA transcripts from lymphoblastoid cell lines of heterozygous patients carrying the mutation were analyzed. RT-PCR of total mRNA showed two main products: the apparently normal transcript and an aberrant, 102 bp shorter transcript. Direct PCR sequencing showed that the aberrant transcript is a consequence of exon 2 skipping. PMID- 9360640 TI - Detection of a point mutation (A to G) in exon 5 of the murine Mgf gene defines a novel allele at the Steel locus with a weak phenotype. AB - A new mutation at the locus encoding the mast cell growth factor (Mgf) is described and designated as MgfSl-3Neu. Homozygous mutants have a light grey fur, sometimes with white patches. Homozygotes are fertile, but with reduced litter size, when mated inter se. Analysis of haematological parameters indicated no difference between mutant and wild-type mice. Sequence analysis of the cDNA obtained from the brain of homozygous mutants revealed an A-->G exchange at position 400 leading to a predicted amino acid exchange from Asn-->Leu at position 122. As a consequence of the predicted amino acid exchange an extension of the alpha-helical context and a decreased hydropathicity of the region at positions 101-125 can be deduced. This single amino acid exchange is outside of the known important domains of MGF and explains the weak phenotype of MgfSl-3Neu. PMID- 9360641 TI - Water channel AQP1, 3, and 4 in the human peritoneum and peritoneal dialysate. AB - To clarify the mechanism of water transport driven by osmotic gradient through "ultrasmall pores" in the peritoneum, we tried to identify water channels in the peritoneum and cells in the peritoneal dialysate. Peritoneum was surgically excised from uremic patients at the insertion or removal of a catheter. Sediment was collected from 2 L of peritoneal dialysate by centrifugation at 1500 rpm. RNA was extracted and amplified by reverse transcription-polymerase chain reaction (RT-PCR). Contamination of reticulocytes was tested by the presence of ankyrin mRNA. Peritoneal tissue expressed aquaporin (AQP) 1, 3, and 4 (AQP1 > 3 > 4). Sediment of dialysate expressed mRNA of AQP1 and AQP3 (AQP1 > AQP3). The sample did not express ankyrin mRNA, indicating that the AQP1 in the sediment did not originate from reticulocytes. These data indicate that aquaporins are present in the peritoneum and might participate in water transport. Further quantitative analysis of aquaporin messages in the dialysate might clarify the pathogenesis of water removal failure. PMID- 9360642 TI - Peritoneal dialysis effluent, cytokine levels, and peritoneal mesothelial cell viability in CAPD: a possible relationship. AB - Recent studies have emphasized the role of peritoneal mesothelial cell (PMC) in peritoneal immune defense mechanisms in continuous ambulatory peritoneal dialysis (CAPD). The aim of this study was to evaluate a possible relationship between peritoneal dialysis effluent (PDE), cytokine (Cy) levels, and PMC viability and their impact on peritonitis morbidity. Fifteen patients initiating CAPD for end stage renal failure participated in the study. The following parameters were evaluated: (1) the levels of interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-6 (IL-6), and interleukin-8 (IL-8) in PDE samples taken 7 days after initiating CAPD, at the end of the first, third, and sixth month of CAPD (determined by a solid phase enzyme amplified sensitivity immunoassay EASIA); (2) peritoneal mesothelial cell viability [determined by the release of lactate dehydrogenase (LDH) and by trypan blue extrusion test] by isolating and culturing peritoneal mesothelial cells at the moment of the placement of the peritoneal catheter and at the sixth month of CAPD; (3) peritonitis incidence during the 24 months after starting CAPD. At the first month of CAPD in all patients there was a slight increase in PDE IL-1 beta and TNF-alpha levels, while other Cy were almost undetectable. Time course studies showed that in 10 patients (Group I) there was a significant increase in PDE levels of IL-6, IL-8, and INF-gamma (p < 0.0005) in comparison to other Cy and a good PMC viability. In the other 5 patients (Group II) there were higher PDE levels of IL-1 beta and TNF-alpha (p < 0.0005). This was associated with a marked reduction in PMC viability determined by the release of LDH and by the trypan blue extrusion test. During the 24 months after starting CAPD, incidence of peritonitis was one episode per 24 patient-months in Group I and one episode per 9.2 patient-months in Group II. Our results show that from the beginning of CAPD there are distinct patterns of Cy in the PDE that correlate with a different PMC viability and peritonitis morbidity. Thus the analysis of the above-mentioned parameters may be useful in the early identification of the risk of peritonitis, thus allowing preventive measures. PMID- 9360643 TI - DNA synthesis of cultured mesothelial cells in a high permeable state. AB - To understand the mechanism of regeneration of the mesothelial cell in a high permeable state, in vitro experiments with cultured mesothelial cells were carried out using a type I collagen-coated multititer plate. Prior to cell seeding, each plate was filled with 100 microL of glucose solution at concentrations of 30 mmol/L, 90 mmol/L, and 150 mmol/L, and minimum essential medium (MEM), respectively. After immersion for one to five weeks at 37 degrees C, mesothelial cells were seeded at a density of 3 x 10(4)/cm2, then glucose was added at varying final concentrations between 0 and 150 mmol/L and/or albumin was added at a final concentration of 2 g/dL. After days 2 and 4, DNA synthesis was measured by incorporation of 5-bromo-2'-deoxy-uridine (BrdU). There was no significant difference of DNA synthesis between groups with and without one-week glucose immersion when mesothelial cells were cultured with only 10% FCS/MEM. However, suppression of DNA synthesis at 2 g/dL of albumin was seen no matter what concentration of glucose supplement was used. Without a high concentration of albumin, DNA synthesis was dose-dependent on glucose. The longer the immersion period, the lesser the suppression. It is speculated that process of glycation with collagen may relate to growth of mesothelial cells. PMID- 9360645 TI - Time dependence of solute removal during a single exchange. AB - The viability of long-term peritoneal dialysis (PD), especially once residual renal function is lost, has been challenged since recently recommended weekly targets of Kt/V of 2.1 and creatine clearance (Ccr) of 70 L/1.73 m2 may be difficult to reach. This study demonstrates the theoretical possibility of achieving these targets in PD patients even without residual renal function. A 6 hour dwell study was performed in 68 PD patients with frequent dialysate and plasma sampling using 2 L of 1.36% (n = 13), 2.27% (n = 9), or 3.86% glucose dialysate (n = 46) with 131I albumin as an intraperitoneal volume marker. Alterations in fluid balance, Kt/V, and Ccr with dwell time (t) as well as the impact of peritoneal fluid absorption on peritoneal fluid and solute removal were evaluated. Kt/V and Ccr did not follow an exponential function with t and, in fact, decreased after 4-5 hours, especially in high transporters. All patients could achieve either weekly Kt/V (especially low transporters) or Ccr target (especially high transporters) if they are treated with automated PD. Calculations showed that eliminating fluid absorption could increase mean fluid removal by 43%-179%, increase mean Kt/V by 17%-32%, and mean Ccr by 16%-30% (depending on the solution used and the patient's peritoneal transport pattern) during a 6-hour dialysis exchange. We reached the following conclusions: (1) Kt/V(urea) and Ccr are markedly time-dependent during a single exchange due to the substantial impact of peritoneal absorption and may, in fact, decline after 4 hours, especially in high transporters. (2) Extrapolating Kt/V and Ccr values from short dwell times [i.e., peritoneal equilibration test (PET) results] to long dwell times will overestimate the peritoneal clearances. (3) Enough fluid removal must be considered as an important target of adequate dialysis along with small solute clearances. (4) If fluid absorption could be eliminated, most continuous ambulatory peritoneal dialysis (CAPD) patients could achieve the recommended Kt/V and/or Ccr targets even without residual renal function. PMID- 9360644 TI - Markers of peritoneal mesothelial cells during treatment with peritoneal dialysis. AB - Loss of peritoneal mesothelial cells and decrease of mesothelial cell mass have been described in peritoneal dialysis (PD) patients. Longitudinal follow-up in individual PD patients cannot be performed by serial peritoneal biopsies. Markers of mesothelial integrity, measured in the effluent, may therefore be a valuable approach to detect changes in the mesothelium in vivo. In the present study, markers that are known to be produced by mesothelial cells were followed in individual patients: cancer antigen 125 (CA125), phospholipids (PHL), and hyaluronan (HA). CA125 is considered to be a reflection of mesothelial cell mass or stable mesothelial cell turnover. Appearance rates (AR) were determined in the effluents of 30 PD patients on a yearly basis. Median AR (range) were: CA125: 111 U/min (10-610), PHL: 15 mg/min (3-46), HA: 666 mg/min (135-6200). Cross sectionally, the AR for CA125 was negatively related to duration of PD (r = 0.47, p < 0.0001) and weakly related to peritonitis incidence (r = -0.20, p < 0.05). Patients treated with PD for more than 4 years had lower CA125 appearance than patients treated less than 4 years (p < 0.0004). HA was also related to the incidence of peritonitis, but positively (r = 0.32, p < 0.004). PHL were not related to either parameter. A significant negative trend with time of PD treatment was observed for CA125 only [mean regression coefficient (t) -3.75, SD 1.2]. No trend in time of PD treatment could be detected for HA and PHL. These data indicate a gradual loss of mesothelial cell mass during PD by the decrease of CA125 with time. The lack of a decrease in HA and its positive relation to incidence of peritonitis suggest an additional release of HA by cells other than the mesothelial cells, such as fibroblasts and leukocytes. Alternatively, an activation of (mesothelial) cells with duration of PD and possibly with increased peritonitis incidence cannot be excluded. The relation between PHL and duration of PD suggested by others was not confirmed in this study. PHL are probably released by a number of different cells, and therefore changes in PHL cannot be used as a reflection of changes in mesothelial cell mass. It is concluded that CA125 is the most specific marker for the follow-up of mesothelial cell mass in vivo. PMID- 9360646 TI - Differences in fluid and solute transport between diabetic and nondiabetic patients at the onset of CAPD. AB - Loss of transcapillary ultrafiltration (TCUF) can occur during continuous ambulatory peritoneal dialysis (CAPD) and may be caused by exposure to the high glucose concentrations in the dialysate, leading to glycation of water channels in the endothelial cells of the peritoneal microvessels. If this hypothesis is correct, diabetic patients should have lower TCUF rates at the onset of CAPD than nondiabetic controls. Such a difference should disappear during longer-duration CAPD because of the continuous glucose exposure in both groups, induced by the high glucose concentrations in the dialysate. Therefore, the standard peritoneal permeability analysis of 11 diabetic (mean age 48 years, range 33-70 years) and 11 nondiabetic patients (mean age 49 years, range 36-69 years) matched for sex, age, and duration of CAPD were studied shortly after the onset of CAPD treatment (mean duration 162 vs 131 days) and one year later. No differences were found in solute transport or protein clearances between the two groups at the onset of CAPD. The TCUF rate was lower in the diabetic patients: 0.9 mL/min (0.09-2.25) versus 1.51 mL/min (0.97-2.44), p = 0.01. The other parameters of fluid transport were not different. The mean osmotic pressure gradient, exerted by albumin and glucose, was 1.72 mmHg in the diabetic patients and 5.44 mmHg in the controls (p = 0.0004). No differences were found in peritoneal permeability, including TCUF, after one year between the two groups. In conclusion, the TCUF rate was lower in diabetic patients compared to nondiabetics only shortly after the onset of CAPD. These results suggest that long-term exposure to high glucose concentrations in diabetics prior to CAPD may cause changes in capillary wall aquaporins, similar to long-term exposure to high glucose concentrations in the dialysate in CAPD. PMID- 9360648 TI - An analysis of the determinants of urinary urea and creatinine clearance in patients on continuous peritoneal dialysis. AB - The relative contribution of urinary volume (UV) and urine-to-plasma concentration ratios for urea (U/PUr) and creatinine (U/PCr) to urinary Kt/V urea (Kt/VU) and urinary uncorrected creatinine clearance (CCrU), respectively, was studied by simple and multiple linear regression analysis in 236 urea kinetic studies and 233 creatinine kinetic studies performed in 135 patients on continuous peritoneal dialysis (CPD). The following simple regressions were obtained: Kt/VU = 0.09 + 0.72 (UV), r = 0.75; Kt/VU = -0.01 + 0.11 (U/PUr), r = 0.55; CCrU = 12.06 + 56.46 + 46.46 (UV), r = 0.62; CCrU = 3.51 + 3.40 (U/PCr), r = 0.58. All r values were significant (p < 0.001). According to these regressions, a loss of 0.2 L/24 hours in UV leads to a loss of 0.15 weekly in Kt/VU and 11.3 L/1.73 m2 weekly in corrected CCrU (approximately 8 L/1.73 m2 weekly in corrected CCrU). By multiple linear regression, (1) Kt/VU = -0.38 + 0.70 (UV) + 0.10 (U/PUr). Standardized coefficients were 0.72 for UV and 0.51 for U/PUr (2) CCrU = -33.36 + 59.83 (UV) + 3.63 (U/PCr). Standardized coefficients were 0.65 for UV and 0.61 for U/PCr. UV is the most important determinant of both urea and creatinine urinary clearances in CPD patients. The contribution of the U/P ratios to the urinary clearances is important, but less than that of UV. The primary dependence of urinary clearances on UV allows the use of UV, which can be easily monitored by patients, as a first approximation index of changing residual renal function in CPD. PMID- 9360647 TI - Estimating the daily dialysate drain volume required in CAPD for a target peritoneal creatinine clearance by body water and peritoneal transport characteristics. AB - Stepwise logistic regression performed in 324 clearance studies in 194 patients identified daily drain volume normalized by body water (DV/V) and peritoneal solute transport type as the predictors of peritoneal creatinine clearance (CCrp) in continuous ambulatory peritoneal dialysis (CAPD). Solution of the regression model for DV/V provided DV/V values predicted to provide a desired CCrp at different probabilities. The ability of the predicted DV/V to detect desired CCrp values was tested in a new set of 359 clearance studies in 217 CAPD patients who had a peritoneal equilibration test within 12 months of the clearance study. No patient with low transport had a CCrp exceeding 54 L/1.73 m2 weekly. The following DV/V values detected CCr > or = 54 L/1.73 m2 weekly with a probability of at least 80%: for low-average transport, 0.406 L/L per 24 hours; for high average transport, 0.339 L/L per 24 hours; for high transport, 0.241 L/L per 24 hours. Corresponding DV/V values for a CCrp of 60 L/1.73 m2 weekly were as follows: for high-average transport, 0.351 L/L per 24 hours; for high transport, 0.271 L/L per 24 hours. For high-average transport, maximal body surface area (BSA) estimates allowing a CCrp of 60 L/1.73 m2 weekly at a CAPD schedule of four daily exchanges with 3-L exchange volume and 1.5 L/24 hour ultrafiltration volume, and with the specified DV/V values were 2.03 m2 in women and 1.77 m2 in men. Corresponding BSA estimates for high peritoneal solute transport were 2.58 m2 in women and 2.21 m2 in men. The delivered dose of CAPD, expressed as DV/V, required to achieve a target CCrp can be calculated from multivariate statistical models taking into account the peritoneal solute transport type. Multiplication of the required DV/V by V provides an estimate of the required daily exchange volume. Maximal BSA estimates allowing a target CCrp can be calculated for each gender and peritoneal solute transport type. PMID- 9360649 TI - Long-term effects of glycylglycine peritoneal dialysis solution with neutral pH on peritoneum in rats. AB - This study was designed to test the morphological and functional effects of neutral, bicarbonate-based peritoneal dialysis solution containing glycylglycine on the peritoneum of chronically dialyzed rats. Peritoneal dialysis catheters were implanted in 36 rats. The animals were dialyzed twice daily for 4 weeks with a solution containing bicarbonate (35 mmol/L), glycylglycine (10 mmol/L), and 4% of anhydrous glucose (pH 7.35) (group 1; n = 18) or with lactate-based standard 4.25% Dianeal (pH 5.3 (group 2; n = 18). At the beginning of the study, reabsorption of glucose was slower in group 1 (p < 0.02); at the same time, the hyaluronic acid level in the effluent was higher in this group (p < 0.05). However, towards the end of the study these differences disappeared. After 4 weeks of dialysis in rats exposed to bicarbonate-based solution only, the transperitoneal loss of proteins was slower. In morphological studies of the parietal peritoneum, we detected no statistically significant differences between control nondialyzed rats and those exposed to tested solutions. In a biopsy of visceral peritoneum a tendency was observed for increased thickness of peritoneum in rats dialyzed with both tested peritoneal dialysis solutions when compared to control animals. In conclusion, neutral pH glycylglycine peritoneal dialysis solutions seem to be more biocompatible than standard dialysis solutions. PMID- 9360650 TI - Extracorporeal losses of insulin-like growth factor-I and insulin-like growth factor binding protein-3 in adult patients on CAPD. AB - The effects of extracorporeal (urinary plus peritoneal) losses of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP 3) on their respective serum levels were studied in 10 adult patients (aged 42-74 years) with end-stage renal failure and residual renal function of 0-4.5 mL/min. All patients had been on continuous ambulatory peritoneal dialysis (CAPD) for a period of 2-27 months. Morning serum, 24-hour urine, and 8-hour overnight peritoneal concentrations of IGF-I and IGFBP-3 were measured by radioimmuno- (Incstar) and immunoradiometric (Active) assays. CAPD patients showed extracorporeal losses (mean +/- SEM) of 118.7 +/- 10.6 micrograms (urinary 6.4 +/ 2.8 and peritoneal 112.3 +/- 8.5 micrograms) of IGF-I/24 hour and 1.5 +/- 0.1 mg (urinary 0.2 +/- 0.1 mg and peritoneal 1.3 +/- 0.1 mg) of IGFBP-3/24 hour. Extracorporeal losses of IGF-I accounted for about 4% of the daily production rate of this polypeptide, and the peritoneal and urinary concentrations of IGFBP 3 did not exceed 4% and 14%, respectively, of their serum levels. Serum concentrations of IGF-I (227.7 +/- 64.2 micrograms/L) and IGFBP-3 (5.3 +/- 2.4 mg/L) were not significantly correlated with extracorporeal, peritoneal, or urinary losses of these proteins or with residual renal function. We suggest that extracorporeal losses of IGF-I and IGFBP-3 in adult patients on CAPD do not influence their serum levels and that IGF-I may therefore be used as a marker of malnutrition. PMID- 9360651 TI - Kinetic analysis of furosine and pentosidine in CAPD patients. AB - Advanced glycation end products (AGEs) have been noted in the peritoneal tissue of continuous ambulatory peritoneal dialysis (CAPD) patients, and this may cause an increase in membrane permeability. In vivo and in vitro kinetic analysis was carried out on furosine and pentosidine, early and late glycation products. Plasma furosine and pentosidine were measured by HPLC in patients with renal dysfunction with or without diabetes mellitus (DM) and dialysate pentosidine and furosine in CAPD patients. Only those dialysis patients without residual renal function were used in this study. Plasma furosine was remarkably high in DM, hemodialysis (HD), and CAPD patients. Plasma pentosidine appeared to depend on renal function and was not influenced by diabetic condition. Plasma pentosidine was significantly higher in CAPD than HD patients. A weak positive correlation was noted between dialysate and plasma furosine and pentosidine, indicating the main source of furosine and pentosidine in PD effluent to be plasma. Serial dialysate sampling showed furosine and pentosidine to increase linearly. Mean dialysate/plasma (D/P) of furosine and pentosidine were 0.043 and 0.012, respectively. Protein-bound product size and in situ formation of furosine in the peritoneal cavity would be the reason for these differences in D/P. In situ formation of early glycation products in the peritoneal cavity may be concluded to take place in CAPD patients, and high plasma pentosidine may lead to its accumulation in tissue, resulting, possibly, in pathological change. PMID- 9360652 TI - Effects of osmotic agents on hyaluronan synthesis in human peritoneal mesothelial cells and fibroblasts. AB - Hyaluronan (HA) plays an important role in peritoneal tissue remodeling and the inflammatory process. In this study, attention was directed to the effects of various osmotic agents on HA synthesis in human peritoneal mesothelial cells (HMCs) and fibroblasts (HFBs). Following incubation with growth arrest media for 48 hours, the cells (4 x 10(4)/mL) were incubated for 72 hours in media at various concentrations (50, 100 mmol/L for crystalloid agents and 3.5%, 7% for oncotic agents) of glucose, mannitol, glycerol, sucrose, raffinose, NaCl, combined amino acids, maltodextrin, dextran 70, and hydroxyethylstarch 20. HA synthesis for 72 hours was measured by sandwich-binding protein assay. HMCs synthesized approximately 0.15 ng/cell/72 hours and HFBs 0.09 ng. All crystalloid osmotic agents significantly suppressed HA synthesis by HMCs and HFBs in a concentration-dependent manner. There was no such suppression by any oncotic osmotic agent, which, to the contrary, enhanced the synthesis by 6%-63% in HMCs. In conclusion, HMCs and HFBs may be considered sources of HA in the peritoneal dialysis effluent. Crystalloid osmotic agents suppressed HA synthesis in these cells. Oncotic osmotic agents seem to be less toxic in this regard. PMID- 9360653 TI - Persistent transforming growth factor beta 1 expression may predict peritoneal fibrosis in CAPD patients with frequent peritonitis occurrence. AB - The efficiency of continuous ambulatory peritoneal dialysis (CAPD) depends on the permeability of the peritoneal membrane. Peritoneal fibrosis (PF) causes the loss of dialytic function. Several studies have indicated that PF is closely related to the proliferation of peritoneal fibroblasts and the deposition of extracellular matrix (ECM). Transforming growth factor beta 1 (TGF beta 1) plays a major role in stimulating ECM deposition. Frequent peritonitis occurrence may cause persistent TGF beta 1 mRNA expression. In an attempt to search for a factor related to PF, we designed a longitudinal study to measure TGF beta 1 levels in dialysate and TGF beta 1 mRNA expression in peritoneal mononuclear cells (PMNCs) from peritoneal dialysate before, at the onset of and once a week during peritonitis and after peritonitis in patients with high peritonitis occurrence (HPO) and patients with low peritonitis occurrence (LPO). Fifteen patients with a LPO rate and 5 patients with a HPO rate were followed up longitudinally. Meanwhile, TGF beta 1 levels and TGF beta 1 mRNA expression were augmented in peritoneal dialytic fluid before, during, and after the episodes of peritonitis. Peritoneal permeability was evaluated by the peritoneal equilibration test (PET). The results revealed that in the LPO group, TGF beta 1 and TGF beta 1 mRNA were detectable at early stages of peritonitis, but the levels decreased rapidly and were undetectable 2 weeks after peritonitis. On the other hand, in the HPO group, TGF beta 1 and TGF beta 1 mRNA persisted for a long time. We could detect TGF beta 1 and TGF beta 1 mRNA in dialytic fluid and PMNCs even 2, 3, and 4 weeks after episodes of peritonitis. When compared with that of the first or second episode of peritonitis, peritoneal function evaluated with the PET was found to obviously deteriorate at the third episode of peritonitis. These findings were confirmed by an in situ hybridization technique to evaluate the relationship between TGF beta 1 mRNA expression and PF from biopsied peritoneal specimens. These findings suggest that the high TGF beta 1 levels in the dialysate are related to an increased expression of TGF beta 1 in the peritoneum. Persistent TGF beta 1 expression in the peritoneum may serve as a useful parameter in predicting PF in CAPD patients with frequent peritonitis occurrence. PMID- 9360654 TI - Restriction coefficients of low molecular weight solutes and macromolecules during peritoneal dialysis. AB - The intrinsic permeability of the peritoneal membrane can be functionally represented by the restriction coefficient (RC). The RC can be calculated as the exponent of the power relation between the mass transfer area coefficients (MTACs) of various solutes and their free diffusion coefficients in water. When the RC = 1.0, transport is determined by free diffusion only, as is expected for low molecular weight (LMW) solutes. A RC > 1.0 suggests that transport is restricted by the peritoneal membrane in a size-selective way, as has been found previously for macromolecules (MM). RCLMW can be calculated using the MTACs of urea, creatinine, urate, and beta 2-microglobulin, whereas RCMM can be calculated from clearances of beta 2-microglobulin, albumin, IgG, and alpha 2-macroglobulin. RCLMW and RCMM were determined in 108 peritoneal dialysis (PD) patients. In 36 patients, 3 or more (range 3-13) observations for RCLMW during a period of at least 2 years were available. RCMM were analyzed when present in the same patients. The median cross sectional values (n = 108) were: RCLMW: 1.22 (range 0.75-2.18) and RCMM: 2.30 (range 1.86-3.27). RCLMW was not correlated with time on PD, neither cross sectionally (r = -0.07, NS) nor after analysis of trend (mean regression coefficient t = 0.26, SD = 0.07). For RCMM a positive correlation with duration of PD was demonstrated (cross sectionally r = -0.18, p = 0.02, analysis of trend: t = 2.27, SD = 0.11, n = 27). Both RCs were not interrelated (r = -0.18, NS). The absence of a relation between both RCs suggests that LMW solutes and MM are transported by different pathways. The mean value of 1.22 for the RCLMW illustrates that the transport of LMW solutes is mainly by free diffusion, through the small-pore system. MM, which have to pass through the large-pore system, are restricted by the peritoneal membrane in a size-selective way, as shown by the high value of the RCMM. The lack of a correlation between the RCLMW and duration of PD indicates that no systematic changes occur in the small pores of the peritoneal vessels. In contrast, the increase of RCMM with duration of PD suggests restrictive changes at the level of the large-pore system. PMID- 9360655 TI - Effect of low-frequency ultrasound on peritoneal transport in rabbits. AB - It has recently been suggested that sonophoresis, or the application of ultrasound (US) in the kilohertz range, could enhance peritoneal mass transport. To examine this hypothesis, six nephrectomized rabbits were exposed to ultrasound while under isoflurane anesthesia. An additional five also had bilateral nephrectomies and were used as a control group. Each group underwent four exchanges of 90 minutes duration with 1.5% dextrose while anesthetized. Dialysate samples were taken at 0, 30, 60, and 90 minutes and assayed for urea, creatinine, glucose, and protein. Blood samples were taken pre- and postexchange. In the US group, 20 kHz ultrasound was applied during exchanges 2 and 3 at 47.5 W and 95 W, respectively, using a Virsonic 475 cell disrupter acoustically coupled to the abdomen through a water column and gel-coated PVC membrane. Results were analyzed by calculating the mass transfer area coefficient (MTAC) and 90-minute D/P values for each exchange. No significant differences were observed in the absolute means of either parameter between the control and US groups. However, when exchanges 2 to 4 were normalized with respect to exchange 1, the resulting urea D/P means were less for the US exchanges compared to the control (p < 0.05). This suggests a possible decrease in transport through US application. PMID- 9360656 TI - Patient selection issues in peritoneal dialysis. AB - Advances in peritoneal dialysis (PD) technology and better understanding of peritoneal solute transport have expanded the application of this therapy to a larger segment of the end-stage renal disease (ESRD) community. However, adequate patient selection remains an important issue in assuring success of this therapy. Many of the causes for high technique failure with PD can be traced back to poor initial patient selection. The success of PD depends on: (1) the patient's general health and preexisting comorbid conditions, (2) the patient's ability to provide self-dialysis or to procure an adequate partner, and (3) matching therapy to the patient's individual needs. PMID- 9360657 TI - Sleep apnea in renal failure. AB - Sleep apnea is a surprisingly common disorder in end-stage renal disease (ESRD) and chronic renal failure. The symptoms of sleep apnea frequently go unreported or may be misdiagnosed as uremia, depression, chronic illness, or insomnia. A review of the literature was performed to define the prevalence, morbidity, and treatment of sleep apnea syndrome in the ESRD patient. Sleep apnea occurs in at least 60% of ESRD patients. The known complications of sleep apnea include arrhythmias, pulmonary hypertension, and systemic hypertension. In addition, sleep apnea has been implicated in coronary artery disease and strokes. The contribution of sleep apnea to the high mortality from cardiac disease and stroke in peritoneal dialysis and hemodialysis patients is unknown. The causes of the increased prevalence of sleep apnea in ESRD patients are unknown and likely differ from the general population, but the treatment is similar. The literature suggests that modality of renal replacement therapy does not matter; however, large nocturnal volume peritoneal dialysis may worsen sleep apnea. Renal transplantation may be curative. In conclusion, sleep apnea may be an under diagnosed disease in patients on dialysis. There are significant reasons to suspect that sleep apnea may worsen the morbidity and mortality of ESRD, and there are potential successful therapies. PMID- 9360659 TI - More than 17 years of peritoneal dialysis: a case report. AB - Very few patients have undergone long-term peritoneal dialysis (PD). We report a case of a female patient on PD since 26 May 1979. Suffering from malignant hypertension, she developed renal failure in April 1979. The renal biopsy showed a severe vascular nephropathy. She was 50 years old, her body weight (BW) was 45 kg, and her height was 1.49 m. She refused hemodialysis. A Tenckhoff catheter was installed, and 12-hour intermittent PD (IPD), three times a week, was started in the dialysis center. Ten months later, she began nightly home IPD. In March 1985 she started continuous ambulatory PD (CAPD); she was nearly anuric. During the following years, she developed renal osteodystrophy and suffered from repeated hyperparathyroidism requiring multiple surgical interventions, osteomalacia, pseudotumoral calcinosis, and, finally, adynamic bone disease. She is now 67.5 years old, her BW is 34 kg, and she is still using CAPD. This patient has the same Tenckhoff catheter. She never developed peritonitis or an exit-site or tunnel infection. She used acetate dialysis solution for nearly six years and then lactate solution. Presently her peritoneal permeability is of the high average type; dialysis adequacy (weekly Kt/V: 2.15, weekly peritoneal clearance: 58 L/1.73 m2) as well as nutritional parameters are satisfactory. She has moderate anemia without erythropoietin treatment. She maintains a good quality of life. Although the patient lost 11 kg in 17 years, she has maintained good nutritional status. Dialysis adequacy could be achieved despite anuria for more than 11 years. Small body size, absence of infection and catheter-related problems, healthy peritoneal membrane, good acceptance of the technique, and vigilance towards dietary habits may be the keys for satisfactory long-term PD. PMID- 9360658 TI - Peritoneal ultrafiltration and refractory congestive heart failure. AB - This prospective nonrandomized study enrolled 16 patients with congestive heart failure [NYHA (New York Heart Association) III and IV] refractory to a maximal well-tolerated drug therapy. The aims were to evaluate if peritoneal ultrafiltration (PUF) could improve clinical conditions and to determine morbidity secondary to resistant congestive heart failure (RCHF) and PUF. There were 16 patients (12 male, 4 female) with a mean age of 65.4 years (56-81 years) and follow-up of 15.6 months (4-33 months). Thirteen patients had RCHF without end-stage renal disease. Patients were classified as NYHA class IV (n = 11) or class III (n = 5). One anuric patient had been on previous hemodialysis and switched to APD. PUF was obtained with a 2-L hypertonic dialysis solution, once a day (n = 7) or every 2 days (n = 4). Clinical improvement was obtained for all the patients. Weight decreased from 72.2 to 66.7 kg with a weekly ultrafiltration of 3.74 L (2.2-6.5 L). Sodium removal was 79 mmol/day (urinary 43%, peritoneal transport 57%). During the follow-up period, 2 patients received a cardiac transplant since 7 died due to cardiac reasons. Mean hospitalization time was 4.4 and 1.20 per patient per day before and after PUF, respectively. Hospitalization was in keeping with either RCHF (36%), dialysis complications (16%), or miscellaneous causes (48%). Our experience showed that a functional improvement and a better quality of life were achieved for all these patients with a low rate of hospitalization. PMID- 9360660 TI - Characteristics of long-term peritoneal dialysis patients. AB - The records of 734 peritoneal dialysis (PD) patients trained at our center between January 1983 and December 1991 were reviewed, and those who had been on PD more than 5 years were selected to study the characteristics common to long term survivors. We obtained the following results: 22 patients (3%) remained on PD for more than 5 years and 6 patients for more than 8 years (0.8%). Of these, 59.1% were males and 55% white with a mean age of 41.3 +/- 15.1 years and weight 71.1 +/- 14.7 kg. The causes of end-stage renal disease (ESRD) were: diabetes 31.8%, glomerulonephritis 36.4%, and nephrosclerosis 22.7%. The average peritonitis rate was 0.46 episodes/year and hospitalization 4.13 +/- 3.70 days/ year. After 3 years of PD all patients were essentially anuric. The mean 4-hour D/Purea = 0.94 +/- 0.01 and D/Pcreatinine = 0.68 +/- 0.03. Weekly Kpt/Vurea improved from 1.61 to 1.82, Kcreatinine from 40 to 45 L/1.73 m2, and dialysate volume from 11.6 to 14.1 L/day. The normalized catabolic protein rate (NPCR) remained stable at 0.7 g/kg/day. Serum albumin concentrations (SACs) averaged 3.5 g/dL and did not show a trend with time. Weights revealed marked variation with a mean group gain of 3.4 +/- 0.85 kg. Social support was excellent in 19 patients, and 20 were very compliant. Thirteen patients remain on PD, 4 expired, 1 received a transplant, and 4 transferred to hemodialysis. In conclusion, PD can maintain life for prolonged periods of time in the absence of renal function. Longterm survivors are typically of average size, enjoy stable and average peritoneal transport, good social support, remain compliant with therapy, and experience infrequent peritonitis. New PD modalities capable of delivering higher doses and adjustment of prescription based on residual renal function, peritoneal transport, and metabolic needs should increase the proportion of long-term survivors. PMID- 9360661 TI - The efficiency of fractionated parenteral iron treatment in CAPD patients. AB - Some chronic renal failure patients respond poorly to recombinant human erythropoietin (rHuEPO). In continuous ambulatory peritoneal dialysis (CAPD) patients, such a poor response may indicate inadequate dialysis or low body iron stores. To correct iron deficiency, once-a-week intravenous iron supplementation is recommended. However, hemodialysis patients receive iron supplements three times a week. This study was designed to compare the efficacy of iron supplementation between once-weekly and twice-weekly regimens. In both groups, rHuEPO doses were similar. Seventeen CAPD patients were studied. All had hemoglobin levels less than 10 g/dL. Ten patients were given 100 mg intravenous iron once weekly, and 7 were given 50 mg intravenous iron twice weekly until a total iron dose of 600 mg was achieved (stage I). The patients were crossed over to receive another 600 mg iron (stage II). Hematocrit increased significantly in patients receiving twice-a-week iron supplementation (+3.8% and 6%) compared to those receiving once-a-week iron supplementation (+1.3% and 1.4%) during stages I and II. The ferritin levels were not different between the groups. In conclusion, rHuEPO is more effective when administered with intravenous iron. PMID- 9360662 TI - Importance of iron saturation for erythropoietin responsiveness in chronic peritoneal dialysis. AB - There is a great variation in erythropoietin (rHuEPO) requirements in peritoneal dialysis (PD) patients. Although some studies show the importance of higher iron saturation (FeS, > 20%) in hemodialysis patients for a maximal rHuEPO response, data on PD patients are scarce. We followed 38 stable PD patients for 5 months to evaluate the factors that may be responsible for variability in rHuEPO response. All patients received oral iron supplement and erythropoietin subcutaneously twice a week and were divided into three groups according to weekly rHuEPO dose (U/kg): Group I, < 50; Group II, 50-100; Group III, > 100. Hematocrit was maintained at a currently accepted level of 30%-36%. Iron saturation levels were 30.4 +/- 2%, 27.7 +/- 2.5%, and 21.7 +/- 2.5%, and rHuEPO doses were 37.3 +/- 2.4, 71.2 +/- 2.3, and 141.5 +/- 9.7 in Groups I, II, and III, respectively. There were no significant differences in age, sex, etiology of renal failure, parathyroid hormone, serum albumin, blood urea nitrogen (BUN), and creatinine between various groups. These data suggest that rHuEPO requirements are lower in PD patients with higher FeS. FeS may be a good indicator of rHuEPO requirement and responsiveness in PD patients. Achieving higher FeS than the currently accepted 20% may further decrease rHuEPO requirements in PD patients and have significant cost implications. PMID- 9360663 TI - Design of a renal-dependent individualized quality of life questionnaire. AB - The aim of this study was to design a concise, focused questionnaire to measure individuals' perceptions of the impact of their renal condition on their quality of life, taking account of the importance of life domains relevant for the individual. The design of the renal-dependent quality of life (RDQoL) questionnaire was based on that of the Audit of Diabetes Dependent Quality of Life (ADDQoL) diabetes-specific individualized quality of life questionnaire, which was influenced by patient-centered principles underlying the interview method of McGee et al. The questionnaires specify life domains, and the respondents rate personally applicable domains for the importance and impact of the renal condition. Observation in eight U.K. renal clinics, together with 40 in depth interviews with peritoneal dialysis, hemodialysis, and transplant patients, provided the basis for item selection for the RDQoL. The results of the study were as follows: each of the 13 ADDQoL items was relevant and important for renal patients. Additional suggestions for items included physical appearance, dependency, freedom, restrictions of fluid intake, and societal prejudice. In conclusion, unlike other quality of life measures, the RDQoL is an individualized questionnaire measure of the impact of renal disease and its treatment on quality of life. Face and content validity is established for adult renal patients, and the RDQoL is being further evaluated for research and clinical use. PMID- 9360664 TI - Psychosocial factors and clinical outcome on CAPD. AB - Patient dropout from chronic peritoneal dialysis (CPD) and transfer to hemodialysis remains a major problem with patients on CPD. Peritonitis, exit-site infections, and medical complications requiring hospitalization often adversely affect the outcome of CPD. The role of psychosocial factors in determining patient outcome and influencing the rates of these complications is not clear. Our group has employed a variety of instruments, including the Patient Related Anxiety Scale (PRAS), Beck's Depression Inventory (BDI), Kupfer-Detre System II somatic symptom scale (KDS-II), and a patient self-assessed quality of life (PAQOL) questionnaire to assess quality of life and to objectively evaluate the psychosocial status of the patient treated with CPD. The present study extends previous observations by relating the results of these psychosocial instruments to the incidence of various complications in 103 patients maintained on CPD. Patients were divided into low-scoring (lowest symptoms of depression, anxiety, somatic symptoms, and best quality of life evaluation), intermediate, and high scoring (highest symptoms of depression, anxiety, somatic symptoms, and worst quality of life) categories. The peritonitis rates, exit-site infection rates, and days of hospitalization of the three categories were then compared. The results demonstrate significantly higher complication rates in the high-scoring when compared to the low-scoring patients. Thus screening patients maintained on CPD with objective measures of psychosocial functioning may enable caregivers to more accurately predict which patients are at greater risk for developing medical complications. PMID- 9360665 TI - Quality of life assessment in chronic peritoneal dialysis patients. AB - Previous studies by our group have attempted to examine quality of life (QoL) issues in a cohort of end-stage renal disease (ESRD) patients maintained on chronic peritoneal dialysis (CPD) by assessing a variety of psychological tests and by asking patients to rate their own QoL. The present study was undertaken to extend previous observations by asking patients to spontaneously select those domains of life experience that they think are most important in determining their quality of life. Sixty-eight medically stable CPD patients were asked to spontaneously select those three to five domains felt to be most important to them in defining their QoL. The 307 responses were then grouped into 22 broad categories by three investigators. The most frequently selected domains focused on interpersonal relationships. Domains that enhance the quality of one's day and add meaning to one's life were selected with a midrange frequency. Some domains that might intuitively seem to be important for a patient's QoL were selected with a surprisingly low frequency. These findings suggest that to understand what CPD patients value in assessing their QoL can best be determined by asking them directly and not by using predetermined variables. PMID- 9360666 TI - Dialysis adequacy and self-reported health status in a group of CAPD patients. AB - The purpose of the study was to describe in a cross sectional manner the self reported level of health of a group of continuous ambulatory peritoneal dialysis (CAPD) patients and to establish whether any clinical or laboratory variables correlated with this measure of health. While undergoing routine baseline and 6 monthly measurements of weekly total urea over volume distribution (Kt/V) and weekly creatinine clearance (Ccr)/1.73 m2 body surface area (BSA), 57 patients voluntarily completed the Short Form 36 health status questionnaire (SF36) (a self-report, multidimensional, generic measure of health status). Weekly Kt/V was correlated with weekly Ccr (r = 0-81, p < 0.001). Thirty-one of the 57 patients were recorded as having Ccr < 65 L/week. A comparison with Australian interim normative data demonstrated that this group of CAPD patients reported lower scores on the eight physical and mental health components that are measured by the SF36 than did the general population. Patients who were most impaired in their physical functioning were more likely to be older, overweight, and to have a lower normalized protein catabolic rate (nPCR). Patients who were adequately dialyzed (Ccr > or = 65 L/week/1.73 m2) reported greater vitality than those patients recorded as having Ccr < 65 L/week/1.73 m2. PMID- 9360668 TI - Impact of portable APD on patient perception of health-related quality of life. AB - We assessed the impact of the introduction of a portable automated peritoneal dialysis (APD) system (Homechoice, Baxter Healthcare) on health-related quality of life (HRQOL). We evaluated HRQOL in 26 patients using the RAND 36-item Health Survey 1.0, which measures physical functioning, role limitations (physical and emotional), social functioning, emotional well-being, pain, energy, and general health perceptions. Questionnaires were administered prior to changing to the new system and 3 months later. Kt/V and albumin levels were measured at both time points. Eight patients had been on continuous ambulatory peritoneal dialysis (CAPD), and 18 had been using other APD systems (PacXtra, Baxter and AMP80, Fresenius). Kt/V increased significantly (p = 0.026); albumin was unchanged (p = 0.09). There was an improvement in the pain score (p = 0.079), although this did not reach statistical significance in the overall sample. Subgroup analysis showed that most of the improvement was from the group that had used the AMP80. No other statistically significant differences were found overall in the domains of HRQOL. Questioning of a random sample of patients indicated that perceived advantages of the new system were ease of setup and portability within the home. Neither of these translated into improvement in role-functioning domains of HRQOL. The improvement in pain score may reflect the capacity of newer cyclers to switch from drain to fill after a set proportion of dialysate has drained, leaving the patient empty for less of the time. Portable APD systems did not bring about predicted improvements in HRQOL. The HRQOL instrument may be insensitive, but technologically convenient advances may have limited impact on HRQOL due to its multifactorial nature. PMID- 9360667 TI - Psychosocial and psychiatric morbidity in patients on CAPD. AB - Continuous ambulatory peritoneal dialysis (CAPD) is an important mode of therapy for patients with end-stage renal disease. Although techniques and patient survival rates have improved, the psychosocial rehabilitation of Asian CAPD patients has not been studied. The aim of this study is to measure the extent of psychosocial and psychiatric morbidity in a sample of Asian CAPD patients. Patients from the outpatient CAPD facility affiliated with a tertiary care hospital were randomly selected and enrolled in the study. Demographic and clinical data were collected. Psychosocial and psychiatric assessments using the Hospital Anxiety and Depression Scale and coping style questionnaires were performed by a trained psychiatrist. The patients' most bother-some symptoms and specific worries were noted. Thirty of 105 stable CAPD patients (mean age 54.2 +/ 14.1 years, M:F 1:2, mean duration on CAPD 22.3 +/- 8.3 months) were studied. Twenty-one patients were married. Twenty-two patients were uneducated, 19 were unemployed, and 9 were homemakers. Based on the Hospital Anxiety and Depression scales, 50% of the patients were identified as cases of anxiety and 13% as depression. Although 93% of the patients accepted their illness, 46% of the patients were in a state of despair and hopelessness. Pruritus was the most frequent complaint (40%), followed by dietary restrictions (23%). The main worries were financial in 83% of patients, sexual dysfunction in 73%, and unemployment in 67%. In conclusion, Asian CAPD patients have a high degree of undetected psychosocial and psychiatric morbidity. These issues need to be addressed to provide adequate psychosocial rehabilitation. PMID- 9360669 TI - CAPD in southern Brazil: an epidemiological study. AB - There are many studies on the performance of continuous ambulatory peritoneal dialysis (CAPD) in developed countries, but studies in the third world are scarce. The aim of this study is to analyze CAPD experience in the southernmost state of Brazil (Rio Grande do Sul, RS). Records were obtained from the Health Secretary of RS to assemble a cohort of all patients treated with CAPD. Another cohort study followed all patients initiating treatment for uremia in 1993 in the state capital, Porto Alegre, and compared CAPD, hemodialysis, and transplanted patients. In RS, 1316 patients (50.4% male, mean age 45.9 years) were treated in 40 CAPD programs. Despite the initial growth of the CAPD population, it subsequently leveled off. Survival was 78.6% and 40.7% in years 1 and 5, being worse for initial patients of each program, infants, and elders. Technique survival was 57.4% and 10.1% at years 1 and 5. Patients interrupting treatment for any reason had a higher chance of dropout. In Porto Alegre, 294 patients started dialysis during 1993; 21 performed CAPD, 44 had a transplant, and the others were hemodialyzed. Children were treated mostly by CAPD. CAPD patients had less diabetes and ischemic heart disease and received more transplants. Their adjusted actuarial survival (100% year 1; 67% year 3) was no different than hemodialysis. CAPD is not a popular form of renal therapy in RS, and dropout rates are significant. PMID- 9360670 TI - Serum albumin in continuous peritoneal dialysis: absence of universal predictors. AB - Factors shown to affect serum albumin concentration in continuous peritoneal dialysis (CPD) were compared between two CPD populations residing in Greece (patient n = 108) and the United States (patient n = 194). Compared to the U.S. group, the Greek CPD population had higher serum albumin levels (35.1 +/- 4.6 vs 33.9 +/- 5.0 g/L, p = 0.031), was older (61.2 +/- 12.0 vs 52.7 +/- 16.5 years, p < 0.001), and had a greater number of high or high-average peritoneal solute transport types (69.4% vs 52.1%, p = 0.003). The American CPD population had a higher number of diabetics (53.1% vs 27.8%, p < 0.001), higher total Kt/Vurea (2.06 +/- 0.57 vs 1.93 +/- 0.46 weekly, p = 0.046), and higher total creatinine clearance (76.3 +/- 38.7 vs 63.4 +/- 23.5 L/1.73 m2 weekly, p < 0.001), while normalized protein nitrogen appearance values were comparable (0.95 +/- 0.21 in the Greeks vs 0.94 +/- 0.22 g/(kg x 24 hr) in the Americans, NS). A logistic regression model developed in the United States identified advanced age, diabetes, and high/high-average peritoneal solute transport as the predictors of hypoalbuminemia (serum albumin < 35 g/L). This model generated the following areas with 95% confidence intervals (CI) under the receiver operating characteristic (ROC) curve: in the Greek CPD population, ROC area 0.594 (95% CI 0.486-0.702); in the American CPD population, ROC area 0.850 (95% CI 0.810 0.890). In Greek CPD patients serum albumin appears to be affected by factors other than those identified in North America. This complicates comparisons of serum albumin, and probably morbidity and mortality, between CPD populations residing in different parts of the world. PMID- 9360671 TI - Nutritional intake during continuous ambulatory peritoneal dialysis. AB - The purpose of our study was to evaluate the adequacy of nutrition intake in continuous ambulatory peritoneal dialysis (CAPD) patients. In 34 patients, diet histories were taken every 1-3 months simultaneously with adequacy parameter estimations and total nitrogen measurements in dialysate and urine. The results were normalized to 1 kg of ideal (IBM) or lean (LBM) body mass. During the 2-year study period, there was a decrease in the intake (g/kg IBM/day) of carbohydrates (4.2 +/- 1.5 vs 3.4 +/- 1.2), fat (1.3 +/- 0.6 vs 0.8 +/- 0.2), and protein (1.18 +/- 0.43 vs 0.85 +/- 0.11); daily protein intake values were higher than those of protein catabolic rate (0.91 +/- 0.19 vs 0.77 +/- 0.17). Nitrogen balance was positive (6.6 +/- 2.1 vs 1.8 +/- 2.7 g/day). The daily energy intake (40 +/- 11 vs 32 +/- 13 kcal/kg IBM/day) did not show any tendency of increasing or decreasing, stable or otherwise. The mean intake of vitamins and minerals (except Na, K, P) was less than in healthy persons; moreover, in most cases vitamin intake did not reach values recommended for CAPD patients. Protein, mineral, and vitamin intake is usually unsatisfactory in CAPD patients. However, a positive nitrogen balance can be obtained when the energy intake is close to the optimal value of 35 kcal/kg/day. PMID- 9360672 TI - Serum albumin and depression in end-stage renal disease. AB - The purpose of our study was to determine whether albumin influenced patients' depression or whether depression influenced patients' albumin. Patients from a tertiary care university medical hospital were assessed for both serum albumin and depression [Beck Depression Inventory (BDI)] at two time points separated by 6 months. Data were collected for 72 patients (43 male, 29 female; mean age 54 years). The sample consisted of 32 hemodialysis and 40 peritoneal dialysis patients. The outcome measures were changes in depression and albumin over time. Regression analysis indicated that all three Time 1 measures of BDI, BDICOG (BDI cognitive), and BDISOM (BDI somatic) significantly predicted decreases in albumin from Time 1 to Time 2 (beta = -0.22, p < 0.002; beta = -0.17, p < 0.015; beta = 0.23, p < 0.002, respectively). However, Time 1 measures of albumin did not predict changes in BDI, BDICOG, or BDISOM (beta = -0.04, p < 0.738; beta = -0.08, p < 0.375; beta = -0.07, p < 0.618, respectively). Thus depression at Time 1 predicted decreases in albumin from Time 1 to Time 2. The reverse effect that albumin influences depression from Time 1 to Time 2 was not found. In conclusion, this study suggests that depression influences the nutritional status indicated by albumin levels. Thus poor nutritional status may mediate the relation between depression and mortality in end-stage renal disease (ESRD). PMID- 9360673 TI - CAPD, an acceptable form of therapy in elderly ESRD patients: a comparative study. AB - Rapid growth in the number of dialysis patients over the age of 65 is occurring coincidentally with the overall aging of the general population. Elderly patients are often poor and physically incapacitated, needing family or social support. These patients may also be susceptible to malnutrition and have multiple complicating medical disorders in addition to end-stage renal disease (ESRD). Thus the selection of an appropriate dialysis modality is particularly critical in elderly patients. Continuous ambulatory peritoneal dialysis (CAPD) offers many advantages to elderly patients, including hemodynamic stability, steady-state chemistries, and no need to create a vascular access. However, little data are available in the literature documenting the use of CAPD in this setting. Therefore, to evaluate the efficacy of CAPD in elderly patients, we retrospectively reviewed the clinical outcomes of 23 patients 65 years of age or older at the start of CAPD (elderly group). Then for each of these patients, 23 comparison subjects younger than 65 were chosen from CAPD patients at our hospital (control group). The control group was matched for sex, CAPD duration, cause of ESRD, and initial connection device. In the elderly group, 23 patients (12 male, 11 female) with a mean age of 70 +/- 4 years (range 65-86 years) were treated with CAPD for 15 +/- 17 months. In the control group, 23 patients (12 male, 11 female) with a mean age of 41 +/- 11 (range 18-57) were treated with CAPD for 16 +/- 17 months. Diabetic nephropathy was the cause of ESRD in 35% of patients. The negative CAPD selection of patients was higher in the elderly group (61% vs 17%, p = 0.0025) as well as in the group that needed a helper (61% vs 17%, p = 0.0025). The exit-site infection and peritonitis rates were not statistically different between the two groups (0.43 vs 0.91 episodes/patient year and 1.46 vs 2.03 episodes/patient-year). The dialysate leakage and bleeding rates were comparable (13% vs 22% and 9% vs 9%). One-year catheter survival was similar in the elderly and younger patients (87.5% vs 84.0%). Although the negative CAPD selection of patients was higher in the elderly group, outcomes were similar to those seen in younger patients. Therefore, CAPD is an acceptable form of therapy for the elderly ESRD patients, particularly if a helper can participate. PMID- 9360674 TI - New principles, better practices, and clearer perceptions in intraperitoneal chemotherapy: clinical experience using icodextrin 20 as a carrier solution. AB - The rationale for using intraperitoneal chemotherapy is based on three phenomena: certain types of tumor are confined to the abdominal cavity for many years; the ability to deliver the drug directly to the surface of tumor deposits; the pharmacological advantage of attaining high local concentrations of the drug within the cavity. Current techniques of intraperitoneal chemotherapy do not use a specially designed carrier solution, which greatly restricts flexibility and does not permit continuous ambulatory intraperitoneal chemotherapy necessary for optimal use of cell cycle-specific antitumor agents. Using icodextrin 20 as a carrier solution containing 50% of the dose of 5-fluorouracil in a 24-hour dwell, simultaneously with a 24-hour elastomeric infusor device containing 50% of the dose, we have succeeded in carrying out continuous ambulatory intraperitoneal chemotherapy, 5 days out of 7 for up to 12 weeks, exposing the peritoneal contents to drug concentrations a thousand-fold greater than attained in the serum in a Phase I clinical trial. These studies have for the first time demonstrated that it is possible to expose continuously for long periods intraperitoneal tumor deposits to sustained high levels of cell cycle-specific cytotoxic agents. PMID- 9360675 TI - The effect of change of renal replacement therapy on serum lipoprotein (a) concentration. AB - Lipoprotein (a) [Lp(a)] is an independent atherogenic risk factor. Lp(a) levels are elevated in patients on renal replacement therapy (RRT). This study looked at the effect of change of RRT on serum lipid and Lp(a) levels. Three groups were identified: (1) patients on dialysis who were transplanted; (2) those who had lost their transplants through immunorejection; (3) those who changed from continuous ambulatory peritoneal dialysis (CAPD) to hemodialysis (HD). All Lp(a) measurements were taken at least 3 months after the change of therapy. Our results were as follows: Group A (n = 21): 8 CAPD and 13 HD patients were transplanted. Median Lp(a) levels fell posttransplantation in the CAPD group (15.6 mg/dL vs 11.4 mg/dL, p = 0.04). The HD group showed a rise in cholesterol, low-density (LDL) and high-density lipoprotein (HDL) levels, with no change in Lp(a) levels. Group B (n = 11): 7 patients started CAPD and 4 HD. Overall, there was a marked increase in Lp(a) levels: median 38.2 mg/dL vs 55.9 mg/dL (p = 0.04), reflecting an increase in those starting CAPD (27.8 mg/dL vs 60.0 mg/dL, p = 0.01), with little change in the HD group (40.45 mg/dL vs 40.05 mg/dL). However, there was a decrease in cholesterol (7.4 mmol/L vs 5.1 mmol/L, p = 0.002) and LDL (5.5 mmol/L vs 3.3 mmol/L, p = 0.004). Group C (n = 16): 16 patients changed from CAPD to HD. Lp(a) levels were higher while on CAPD, as compared to when on HD (58.9 mg/dL vs 49 mg/dL, p = 0.03). Cholesterol (6.62 mmol/L vs 5.26 mmol/L, p = 0.006) and LDL (4.48 mmol/L vs 3.40 mmol/L, p = 0.004) were also higher when on CAPD. In conclusion, serum Lp(a) levels are clearly affected by the mode of the RRT, being highest in CAPD, and decline after transplantation or conversion to HD. Atherogenic risk is thus likely to differ between the modes of RRT and may be greatest for those on CAPD. PMID- 9360676 TI - LDH isoenzyme of the dialysate in noninfected PD patients. AB - We wished to investigate lactic dehydrogenase (LDH) and its isoenzymes in the dialysate of peritoneal dialysis (PD) patients under noninfected conditions. Twenty-seven continuous ambulatory peritoneal dialysis (CAPD) patients (20 males, 7 females; mean age 53 years; average duration of CAPD 29 months) were studied. Overnight dialysate and blood samples were collected. LDH activities, isoenzymes, glucose, creatinine of both specimens, and cancer antigen 125 (CA125) of the dialysate were determined. Serum and dialysate LDH was 470 +/- 163 and 10 +/- 4 U/L, respectively. Percentages of LDH1, LDH2, LDH3, LDH4, and LDH5 were 29 +/- 5, 37 +/- 4, 20 +/- 3, 9 +/- 4, and 6 +/- 2 (%) in the serum, 21 +/- 5, 30 +/- 5, 23 +/- 6, 16 +/- 4, and 8 +/- 3 (%) in the dialysate, respectively. There was no significant relationship between the serum and dialysate LDHs. There were no correlations between dialysate LDH, patient's age, duration of CAPD, peritoneal transport properties, and dialysate CA125. Although it was still difficult to determine the origin of dialysate LDH, a predominance of LDH5 was not observed in noninfected stable patients. Dialysate LDH activities were low, and the isoenzyme patterns were similar to those of the serum. Alteration of the isoenzyme patterns may suggest unfavorable events, such as infection, in the peritoneal cavity. PMID- 9360677 TI - Advantages of HCO3 solution with low sodium concentration over standard lactate solutions for acute peritoneal dialysis. AB - The aim of this study was to identify the advantages of a bicarbonate solution with a low sodium concentration. Twelve children (3 days-6 years) with acute renal failure (ARF), positive fluid balance, and lactate acidosis (> 40 mg/dL) were treated by automated peritoneal dialysis (APD) with frequent exchanges of small fill volumes of a hypertonic solution. For Day 1 we used PD1/PD4 Dianeal (3.86%) (Baxter). After 24 hours we switched to a HCO3 solution: 38 mmol/L, Na 128 mmol/L. As the control group, we studied retrospectively the last 12 children of the previous period who were treated with APD. The age distribution was 4 days to 4 years. No significant differences were found between the groups for serum creatinine, blood urea nitrogen, and fluid overload (Day 1 to Day 4). Although the values for lactate and Na were not different before the start of the study (Day 1) and after 24 hours of Dianeal (Day 2), they were significantly lower in the study group on Day 4 [HCO3 53 (23-83), Na 148 (137-136) mEq/L] than in the control group [lactate 148 (137-156), Na 154 (142-165) mEq/L]. A low sodium concentration results in higher sodium extraction, which is important for patients with fluid overload. Low sodium concentrations in APD are needed because the peritoneal membrane "sieves" the sodium during short dwells. HCO3 dialysis is a logical choice for patients with lactate acidosis, resulting in a significant lower serum lactate and increase of BE after 48 hours of treatment. PMID- 9360678 TI - Reduction of infectious complications and costs using temporary subcutaneous implantation of PD catheters. AB - A limited number of authors have demonstrated that temporary subcutaneous implantation of peritoneal dialysis catheters ("Moncrief") reduces infectious complications and increases catheter life expectancy. Two operations are required to use the Moncrief catheter as compared to only one operation when peritoneal dialysis catheters are exteriorized for immediate use ("Updike"). The questions arise, then, are these findings reproducible and which catheter is the most cost effective? In an effort to support these premises, a retrospective review of 195 patients who received peritoneal dialysis catheters from 1991 to 1995 was undertaken. Demographics, complications, life expectancy analysis, and costs were compared between Moncrief and Updike catheters. There were no significant differences between the groups, and comparisons revealed a clinically evident and statistically significant decrease in the incidence of infections with Moncrief catheters. At both one- and two-year follow-up, Moncrief catheters demonstrated a significant increase in longevity as compared to the Updike catheters. Cost comparisons between the catheter systems revealed that if patients were not undergoing immediate dialysis, placement of a Moncrief catheter was more cost effective. Conversely, if the patient was currently undergoing dialysis, placement of an Updike catheter was more cost-effective. However, sensitivity analysis revealed that shorter exteriorization times would make the Moncrief catheter the more cost-effective choice in this patient population. In conclusion, temporary subcutaneous implantation of peritoneal dialysis catheters significantly decreases the incidence of infectious complications, increases catheter life expectancy, and is the cost-effective choice for patients who will undergo peritoneal dialysis. PMID- 9360679 TI - New perspectives for PD in acute renal failure related to new catheter techniques and introduction of APD. AB - Acute renal failure remains a major problem in pediatric intensive care unit (PICU) patients. Although in most handbooks peritoneal dialysis (PD) is still considered to be the first choice for children < 20 kg and there is some evidence that PD may preserve and/or favor recuperation of renal function, most PICU departments are using continuous veno-venous hemofiltration and dialysis or hemodialysis as treatment. The main reasons for this are workload for the PICU nurses, catheter problems, the risk of peritonitis, and limited ultrafiltration. In a retrospective study (1992-1995) in 46 patients (age 3 days to 14 years), automated PD (APD) was the initial treatment in 44 patients. Complications of the Seldinger-placed Cook (pleuropericard) catheter were limited: leakage (1/44); bleeding: n = 0; obstruction or dislocation: n = 4; peritonitis: n = 1 (Candida); ultrafiltration (UF) problems: n = 3. APD in children with acute renal function (ARF) is a good alternative for continuous veno-venous dialysis. Placement of a pigtail (Cook) catheter is a quick (10 min), safe procedure, with low leakage risk. This, together with the low manipulation rate, gives a low peritonitis rate. The use of the cycler makes frequent changes of small volumes possible, resulting in better clearance, good UF, no interference with hemodynamic or respiratory stability, and a reduced workload. PMID- 9360680 TI - Alterations of intraperitoneal inflammation by the addition of L-2 oxothiazolidine-carboxylate. AB - The authors studied the effect of L-2-oxothiazolidine-carboxylate (OTZ), a substrate for intracellular glutathione synthesis, in an in vivo model of lipopolysaccharide (LPS)-induced peritonitis in rats. The addition of LPS to dialysis fluid increased the white blood cell (WBC) count and the nitrite (index of NO synthesis) level in the dialysate. The simultaneous addition of OTZ to the dialysis fluid prevented an increase of WBCs but not of nitrites in the dialysate. Intraperitoneal inflammation was accompanied by a decrease in net transperitoneal ultrafiltration, an increase in the absorption of glucose, and a loss of protein into the dialysate. OTZ partially reversed the effect of peritonitis on net ultrafiltration. Peritoneal leukocytes from rats exposed to LPS showed a reduced concentration of glutathione, an effect that was reversed in the presence of OTZ. These results show that the supplementation of dialysis fluid with OTZ modified the peritoneal reaction to acute inflammation. PMID- 9360681 TI - Production of IL-1 beta and TNF-alpha by peritoneal macrophages depends on the bacterial species and the inoculum. AB - Peritoneal macrophages (PMs) are very potent producers of proinflammatory stimuli, such as interleukin (IL)-1 beta and tumor necrosis factor (TNF)-alpha. After contact with invading micro-organisms, PMs produce different cytokines, both pro- and anti-inflammatory. Therefore, they are crucial in the regulation of inflammatory events. The aim of this study was to investigate whether the production of IL-1 beta and TNF-alpha is dependent on the bacterial species used. PMs were harvested from spent peritoneal dialysis effluent and subsequently stimulated with five strains of bacteria in two different concentrations. After 24 hours of stimulation, supernatants were harvested and analyzed for both IL-1 beta and TNF-alpha content. IL-1 beta was measured with a commercial ELISA, and TNF-alpha was determined with a bioassay. Both the IL-1 beta and the TNF-alpha production were species-dependent. One strain of Staphylococcus aureus and one strain of Staphylococcus epidermidis induced a markedly higher response in both IL-1 beta and TNF-alpha than the other species. This response was also dose dependent, and this holds true for all species. In conclusion, the IL-1 beta and TNF-alpha response by PMs is both species- and dose-dependent. PMID- 9360682 TI - Decreased L-arginine during peritonitis in ESRD patients on peritoneal dialysis. AB - Deficient production of nitric oxide may be responsible for the defective defense barrier and persistence of bacterial infection. To gain insight into amino acid metabolism and L-arginine-nitric oxide system, we studied 34 end-stage renal disease (ESRD) patients on peritoneal dialysis (PD) (20 males, 14 females, with a mean age of 53.5 years and a mean duration on PD of 29.7 months). The concentrations of amino acids, including L-arginine, were measured in peritoneal dialysate and in the serum. The data demonstrated that patients with ESRD on PD have normal serum amino-acid profiles, whereas those with acute peritonitis develop L-arginine deficiency (from 99 +/- 9 to 52 +/- 9 mumol/L). In addition, levels of asparagine, glycine, proline (nonessential) as well as valine, threonine, and lysine (essential) were reduced in patients with peritonitis. The majority of patients with acute bacterial peritonitis have increased nitric oxide production as judged by the level of nitrites in the dialysate (36 +/- 2 vs 57 +/ 6 mumol/L). The recovery from peritonitis was associated with a decline in nitric-oxide generation. There was a smaller subgroup of these patients that showed paradoxically low nitrite levels during acute peritonitis. The nitrite: L arginine ratio in the peritoneal dialysate was increased in patients with peritonitis, further suggesting the development of substrate deficiency. These findings implicate L-arginine as a conditionally essential amino acid in PD patients with acute peritonitis. Further studies are needed to address the issue of L-arginine supplementation in such patients. PMID- 9360683 TI - Lipopolysaccharide binding protein: a marker for intraperitoneal bacterial infection in patients with CAPD peritonitis. AB - During systemic infection, the serum lipopolysaccharide binding protein (LBP) binds to the lipid A component of bacterial endotoxins and facilitates its delivery to the CD 14 receptor on the cell surface of macrophages, where proinflammatory cytokines are released. There is no knowledge to date whether LBP is also present in the effluent of patients with continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis. We investigated the dialysis effluent of 37 patients with CAPD peritonitis for immunoreactive LBP, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-1 beta and compared the findings with the cytokine levels in 20 noninfected CAPD patients. The mean +/- SEM concentrations of LBP, TNF-alpha, and IL-1 beta were significantly higher in the effluent of patients with peritonitis than in noninfected CAPD effluent. In comparison to controls (0.23 +/- 0.05 microgram/mL), LBP was 0.68 +/- 0.13 microgram/mL in the effluent of patients with CAPD-associated infectious peritonitis. For TNF-alpha, levels were 0.50 +/- 0.25 pg/mL in the control effluent versus 124.7 +/- 46.6 pg/mL in the effluent of peritonitis patients. For IL-1 beta the levels were 0.24 +/- 0.14 pg/mL in the control effluent and 71.23 +/- 17.53 pg/mL in the peritonitis patients. Our findings demonstrate that LBP is significantly elevated in the effluent of CAPD patients during an episode of CAPD-associated peritonitis and might be used as a marker of intraperitoneal bacterial infection. PMID- 9360684 TI - The effects of macrolide and quinolone antibiotics in methicillin-resistant Staphylococcus aureus biofilm growth. AB - Recent studies demonstrate that 14-membered macrolides increase permeability and destruction of Pseudomonas biofilms. The effect of a macrolide antibiotic, erythromycin, on methicillin-resistant Staphylococcus aureus (MRSA) biofilm on Silastic catheter materials in comparison with two different quinolone antibiotics, sparfloxacin (SPFX) and a new quinolone, SYN 1193, was examined. Two different MRSA strains were grown in biofilm, using Mueller-Hinton broth with and without the addition of 10% pooled normal human serum (PNHS), in a modified Robbins device, at 37 degrees C for 24, 48, and 72 hours. Two different clinical MRSA strains were used and minimum bactericidal concentration (MBC) were determined at the time intervals mentioned. Three different dosages of each antibiotic were tested: 5.0, 20.0, and 50.0 micrograms/mL. In addition, a constant dosage of SPFX and SYN 1193, in combination with varying dosages of erythromycin, was tested under similar experimental conditions. SYN 1193 demonstrated the highest MBC in comparison to SPFX; addition of PNHS did not alter the effect of SYN 1193. However, erythromycin alone and in combination with SPFX and SYN 1193 had no effect on MBC. We conclude that (1) macrolide antibiotic erythromycin has poor MRSA biofilm permeability and killing in comparison to SPFX and SYN 1193, and (2) SYN 1193 had the highest MBC to MRSA biofilm. PMID- 9360685 TI - Cefazolin and netilmycin versus vancomycin and ceftazidime in the treatment of CAPD peritonitis. AB - In spite of several recommendations, choosing the initial antibiotic to treat continuous ambulatory peritoneal dialysis (CAPD) peritonitis remains difficult. In our prospective randomized study we attempted to evaluate the efficacy and safety of less toxic combinations of cephalosporins with vancomycin or netilmycin. From November 1993 to September 1996 we treated 52 episodes of peritonitis in 34 patients. Peritonitis was diagnosed according to the valid criteria. Patients were treated for 14 - 28 days with a combination of either cefazolin plus netilmycin or vancomycin plus ceftazidime. The most frequent bacteria causing peritonitis in the two groups were comparable. The efficacy of the cefazolin/netilmycin combination was 91.6% (22/24) without yeasts and 84.0% (21/25) in the vancomycin/ceftazidime combination. There were no statistically significant differences between the two otherwise efficient combinations of antibiotics. No side effects were observed. We believe that the frequent use of vancomycin could be avoided thus reducing the risks of resistance and ototoxicity. PMID- 9360686 TI - Prognosis for patients with sclerosing encapsulating peritonitis following CAPD. AB - Sclerosing encapsulating peritonitis (SEP) is a very serious complication of CAPD. The present study was conducted on 7 SEP patients (4 male, 3 female, average age 33 years) from among 197 continuous ambulatory peritoneal dialysis (CAPD) patients over a period of 14 years. SEP affected 3.7% (7/197) of the CAPD patients in this study, and its annual incidence was found to be 2.6/1000. All 7 patients in this study exhibited ileus. The 3 patients with severe peritonitis and sepsis had transient ileus. The prognosis was poor for 3 patients who reported prior ultrafiltration problems. One of these patients died one year after the onset of SEP. The prognosis for one of the patients showed an intermediate course. SEP patients may possibly be divided into subgroups based on the course of prognosis. SEP patients with previous UF failure and longer duration of CAPD showed poorer prognoses. The quality of life, especially in regard to eating, is poor. PMID- 9360687 TI - Reduced incidence of peritonitis by utilizing "flush before fill" in APD. AB - Studies first theorized and then proved that "flush before fill" decreased the incidence of peritonitis in continuous ambulatory peritoneal dialysis (CAPD). The purpose of this study was to examine the relationship between the incidence of peritonitis and the use of cyclers with the "flush-before-fill" option. We followed our automated PD (APD) population from 1 August 1994 to 30 September 1996. The patients were divided into two groups. Group I utilized cyclers with the "flush-before-fill" option and experienced 8 incidences of peritonitis in 225 patient-months of use, for a peritonitis rate of 1:28. Group II utilized cyclers without the "flush-before-fill" option and experienced 22 incidences of peritonitis in 225 patient-months of use, for a peritonitis rate of 1:10.2. Gram positive organisms were responsible for 3/8, or 37.5%, of incidences of peritonitis for Group I and 13/22, or 59%, of peritonitis incidence for Group II. The results of the study indicate a reduction in both the incidence of peritonitis and the incidence of peritonitis caused by gram-positive organisms for APD when utilizing cyclers with the "flush-before-fill" option. PMID- 9360688 TI - Efficiency of a silver ring in preventing exit-site infections in adult PD patients: results of the SIPROCE Study. Silver ring Prophylaxis of the Catheter Exit Site. AB - A randomized, multicenter clinical trial was conducted to evaluate the efficiency in preventing exit-site infection of a silver ring mounted on peritoneal dialysis (PD) catheter and placed at skin level (designed by Grosse-Siestrup, 1992). Eligible patients stratified by diabetes mellitus were monitored prospectively for 12 months using a detailed structured inventory. New patients starting PD treatment during the study period were followed for at least 3 months. Basic characteristics of the silver ring group (N = 86) and controls (N = 88) such as age, sex, S. aureus nasal carriage, type of PD catheter placement and catheter indwelling time, mode of PD, and number of connections for bag exchanges did not differ significantly between the two groups. Nineteen exit-site infections occurred in the silver ring group and 15 in the control group. The incidence of "equivocal" exit-site findings and time of improvement to a "good" or "perfect" exit site were similar in both groups. Kaplan-Meier analysis of the probability of an infection-free time interval revealed no statistically significant difference between subjects with the silver device and controls. In 6 of the 86 cases, displacement of the silver ring caused severe tunnel infection followed by catheter loss in 2. We conclude that the silver ring used in this setting is not effective in preventing exit-site infections in PD patients. PMID- 9360689 TI - Persistent exit-site/tunnel infection and subcutaneous cuff removal in PD patients. AB - The purpose of our study was to investigate catheter outcome of persistent exit site/tunnel infections (ESI/TIs) in peritoneal dialysis (PD) patients. The patients underwent removal of subcutaneous cuff due to persistent ESI/TI from January 1989 to December 1996 in a tertiary referral university hospital. Two hundred and twenty-three patients (138 male, 85 female) underwent 244 double-cuff coiled Swan neck catheter implantations surgically. Twenty-nine patients (11.8%) had persistent ESI/TI for more than 6 months with the same organism. Sixteen patients (52%) underwent subcutaneous cuff excision. Thirteen (48%) patients refused and were managed conservatively. Two hundred and forty-three episodes of ESI/TI were observed over 4970 patient-months with a rate of 0.58 episodes/patient/year. Twenty-nine patients (11.8%) had persistent ESI/TI with S. aureus in 19, Pseudomonas aeruginosa in 9 (31%), and Serratia marcescens in one (3%) patient. Fourteen (88%) persistent ESI/TIs resolved after subcutaneous cuff excision. None of the patients with ESI/TI responded to conservative treatment. ESI/TI-related peritonitis decreased from 11 episodes to 5 episodes after cuff excision. In contrast, episodes of peritonitis increased from one to 9 with conservative management during a follow-up of mean 18 months (4-38 months). Four (31%) catheters were lost in the conservative group, while 3 (19%) were lost after cuff excision. ESI/TI-related peritonitis decreased after subcutaneous cuff excision but increased with conservative management for ESI/TI. ESI/TI resolved in 88% of the patients after cuff excision, while none resolved with conservative treatment. PMID- 9360690 TI - Frequent recurrence of secondary hyperparathyroidism after pulse oral calcitriol withdrawal in PD patients. AB - The aim of this study was to evaluate the role of pulse oral calcitriol in the control of secondary hyperparathyroidism in peritoneal dialysis (PD) patients, addressing the effects after withdrawal. We studied 15 patients with intact parathyroid hormone (iPTH) plasma levels above 250 pg/mL. The initial calcitriol dose was 8 or 4 micrograms/week, administered in two doses, according to whether the iPTH plasma levels were above or below 400 pg/mL. This dose was modified during the follow-up according to the response. Serum iPTH levels decreased in all patients after the first month (559 +/- 243 to 212 +/- 94 pg/mL, p < 0.001). Serum calcium levels significantly increased during therapy, while serum phosphorus levels did not change. The mean duration of the treatment was 95 +/- 57 days. Nine patients reached the target iPTH levels without complications, and in 6 patients the treatment was interrupted because of hypercalcemia. One month after finishing pulse therapy, a significant decrease in serum calcium levels and an increase in iPTH levels were observed. These values were similar to baseline data and were significantly higher than those found during the pulse calcitriol period. Pulse oral calcitriol administration seems to be a short-term, efficient therapy for secondary hyper-parathyroidism in PD patients. However, after the end of pulse therapy, iPTH serum levels return to baseline values, suggesting long term therapeutic failure. PMID- 9360691 TI - Oral pulsed calcitriol protocol reduces the prevalence of hyperparathyroidism in a PD unit. AB - A quality assessment (QA) activity revealed that the percentage of parathyroid hormone (PTH) levels above 300 micrograms/dL was higher in the peritoneal dialysis (PD) unit than in the hemodialysis (HD) unit (44% vs 27%). To reduce the proportion of patients with a target PTH above 200 micrograms/dL, a protocol that emphasized control of the serum phosphate level, standard pulsed doses of calcitriol, and increased patient education was created for the management of renal osteodystrophy. Serum calcium, phosphate, and PTH levels were obtained according to the protocol from July 1994 through June 1996. The percentage of patients achieving a PTH level below 200 micrograms/dL increased from 40% in June 1994 to 57% in June 1996. Significant differences were found in PTH levels at baseline and at test times 1, 2, and 3. Hypercalcemia (Ca > 12) occurred in 4% of the 532 Ca levels drawn during the study period and were due to breaches of protocol. In conclusion, we have confirmed previous work indicating that pulsed calcitriol can control elevated PTH levels in PD patients. Furthermore, we have developed a protocol that can be used as a QA tool to reduce the prevalence of hyperparathyroidism in the outpatient PD setting without inducing excess hypercalcemia. PMID- 9360692 TI - Impact of metabolic acidosis on serum albumin and other nutritional parameters in long-term CAPD patients. AB - To evaluate the effects of metabolic acidosis on serum albumin and other nutritional parameters in long-term continuous ambulatory peritoneal dialysis (CAPD) patients, we undertook a retrospective study involving 106 CAPD patients who had monthly biochemical measurements and urea kinetic studies every 6 months for more than 2 years. The patients were divided into three groups according to their mean total CO2 (tCO2) level of the 2-year follow-up (Group I: mean tCO2 < 22 mmol/L; Group II: 22 mmol/L < or = tCO2 < 26 mmol/L; Group III: mean tCO2 > or = 26 mmol/L), and the clinical, biochemical, and urea kinetic data were compared between the three groups. The mean tCO2 in Groups I, II, and III were 20.62 +/- 1.2 mmol/L, 23.91 +/- 1.1 mmol/L, and 27.3 +/- 0.8 mmol/L, respectively. The percentage of body weight (Bwt) to ideal body weight (IBW) was significantly higher in Group I (113.1 +/- 15.3%) compared to Group II (103.5 +/- 11.5%) and Group III (98.7 +/- 8.0%) (p < 0.05), but the percentage of lean body mass (LBM) to Bwt was not different between the three groups. Compared to Group III, Group I had significantly higher blood urea nitrogen (BUN) (61.1 +/- 14.3 vs 46.1 +/- 7.2 mg/dL, p < 0.05), serum albumin (4.04 +/- 0.31 vs 3.75 +/- 0.39 g/dL, p < 0.05), and normalized protein equivalent to nitrogen appearance (NPNA) (1.02 +/- 0.21 vs 0.88 +/- 0.14 g/kg/day, p < 0.05), and more ultrafiltration volume (1.4 +/- 0.4 vs 1.0 +/- 0.3 L/day, p < 0.05), in spite of comparable dialysis dose and albumin loss into the dialysate. No differences were observed in the three groups in the changes of tCO2, Bwt/IBW, LBM/Bwt, BUN, and albumin from the baseline values after the 2-year follow-up. Using stepwise multiple regression analysis, NPNA, Bwt/IBW, and ultrafiltration volume were independent factors affecting mean tCO2 level. In conclusion, low tCO2 levels in long-term CAPD patients may reflect increased protein intake, and the mild to moderate degrees of metabolic acidosis may not affect the nutritional status of well-dialyzed CAPD patients. PMID- 9360693 TI - The effect of glucose on the proliferation of peritoneal fibroblasts. AB - The purpose of this study was to clarify the pathophysiological role of glucose and glucose transporters (GLUTs) in the proliferation and production of extracellular matrix (ECM) in peritoneal fibroblasts. Peritoneal fibroblasts from rat omentum were cultured in medium M199 with 5% fetal bovine serum (FBS) with (Group B) and without (Group A) 4% glucose. The rate of cell growth at the M stage of the cell cycle in Group B was higher than that in Group A at 12 and 24 hours after culture. However, cell numbers in Group B were less than in Group A at 24, 72, and 120 hours after culture. The GLUT inhibitor suppressed the proliferation of cells 72 and 120 hours after culture. The procollagen III peptide (PIIIP) contents in the supernatant of cells cultured in a high glucose medium were higher than those of control cells at 24, 72, and 120 hours after culture. PIIIP levels of cells cultured with the GLUT inhibitor were also higher than those of cells without the GLUT inhibitor. These results suggest that initially glucose stimulates cell proliferation and thereafter inhibits its proliferation. GLUTs may accelerate the proliferation of peritoneal fibroblasts. We suggest that glucose stimulates the ECM component PIIIP, and GLUT may have an inhibitory effect on the production of the ECM component PIIIP. PMID- 9360695 TI - Variability of peritoneal equilibration test in children on continuous peritoneal dialysis by repeated testing with solutions of different osmolarity. AB - To evaluate (1) differences in the peritoneal equilibration test (PET) achieved using continuous peritoneal dialysis (CPD) solutions containing different amounts of glucose and (2) intraindividual reproducibility of PETs performed twice within an interval of 8 months on CPD, we investigated 39 PETs in 13 children aged 2.4 19.0 years (median 10.6 years) on stable CPD regimens. The fill volume was 1 L/m2 body surface area. We used a standard CPD solution (Fresenius) with a 2.3% glucose content (groups 2.3a and 2.3b) two times within an interval of 1-8 months. A third test was done between the two with a CPD solution of 1.5% glucose (group 1.5). Equilibration quotients, that is, substrate concentration in dialysis fluid divided by substrate concentration in plasma (D/P), did not show any statistically significant differences between groups 1.5 and 2.3a or between groups 2.3a and 2.3b. A significant difference was seen in the decline of glucose content of dialysate between groups 1.5 and 2.3 but not between groups 2.3a and 2.3b. Ultrafiltration was higher in groups 2.3a and 2.3b compared with group 1.5. Inter- and intraindividual variability between solute transfer was small during follow-up in stable CPD patients. Different glucose contents of 1.5 and 2.3 g/dL dialysis fluid had no measurable influence on PET results of stable CPD patients. For standard PETs, reducing the glucose content of dialysis fluid to isoosmolarity is not necessary. PMID- 9360694 TI - Effects of angiotensin-converting enzyme inhibitors on anemia and erythropoietin requirements in peritoneal dialysis patients. AB - In an attempt to assess the effect of angiotensin-converting enzyme inhibitors (ACEIs) on anemia and recombinant human erythropoietin (rHuEPO) requirements in peritoneal dialysis patients, we evaluated 5 patients treated with ACEIs for one year, and the results were compared with data from a control group (N = 5). In response to ACEIs, the mean hemoglobin value decreased progressively, reaching statistical significance after 6 months and thereafter (basal, 10.7 +/- 0.8; month 6, 10.3 +/- 0.9; month 12, 10.3 +/- 0.5 g/dL, p < 0.05), with no variations in the control group. The rHuEPO requirements experienced a progressive increase in ACEI-treated patients, from 4400 +/- 1516 U/week at basal to 8600 +/- 2880 U/week at the conclusion of the study (p < 0.01). Serum erythropoietin concentration remained stable during the study in both groups of patients. In conclusion, rHuEPO requirements necessary to maintain a stable hemoglobin concentration are greater in subjects under ACEI therapy. ACEI may be an important cause of resistance to rHuEPO, an effect not mediated by a decrease in endogenous erythropoietin. PMID- 9360696 TI - Changes in body composition assessed by bioimpedance analysis in the first 6 months of chronic peritoneal dialysis. AB - Dietary protein restriction, progressive loss of renal adaptive capacity, and uremic toxicity may contribute to the development of malnutrition and water retention in severe chronic renal failure (CRF). Malnutrition is also common in children treated with chronic peritoneal dialysis (CPD). It is not clear how the start of CPD influences body composition of children with CRF. We used a bioimpedance analysis device (BIA 101S Akern) to measure resistance and reactance in 7 children, with residual creatinine clearance of about 5 mL/min/1.73 m2 at the start of CPD (t0) and repeated the test 6 months later (t1). Distance (D), which is considered a reliable index of hydration and nutrition, was obtained from resistance (R) and reactance (Xc) by calculating phase angle (PA). BIA values of our patients were compared with those of healthy children of the same statural age from a series of 551 controls. There was an overall improvement of Xc, PA, and D after 6 months of CPD. In some cases D did not normalize, which indicates that some children with CRF on a restricted protein diet may present changes of body composition that are only partially reversed by short-term CPD. The present indications for the start of CPD should probably be reassessed, at least in some cases, to prevent malnutrition. PMID- 9360697 TI - Improved dialysis dose by optimizing intraperitoneal volume prescription thanks to intraperitoneal pressure measurements in children. AB - An optimal intraperitoneal volume (Vip) may be the most critical and least-used option to enhance higher clearances of small solutes. A higher Vip is more effective in increasing small solute clearances when compated to a lower Vip and more frequent exchanges. Additionally, a higher Vip generates minimal intraperitoneal pressure (Pip) in the supine position. Therefore, the highest tolerated Vip should be used at night while the child is sleeping in the supine position. Therefore, in 5 children, mean age 7 years, 4 months, on continuous cyclic peritoneal dialysis (CCPD) (Baxter HomeChoice), we tested the impact of Vip on tolerance (measured by Pip) measurements, and efficiency [assessed by daily Kt/Vurea and weekly creatinine clearance (Kcreatinine]. Basal Pip was determined for the usually prescribed Vip. Then Vip was increased during a morning outpatient study day, in 30-minute stages, stepping up to an increase of 25% of the basal Pip (upper limit 18 cm of water) level reached at the so-called optimized Vip used for the prescription of an optimal total dialysate volume for a 4-week period. The latest study week was compared to the prestudy week. The optimized Vip of 1230 +/- 70 mL/m2 was significantly higher than the basal Vip, 940 +/- 90 mL/m2. The dialysis dose improved both in terms of Kt/V urea from 0.23 +/- 0.02 to 0.29 +/- 0.03 and Kcreatinine from 60 +/- 5 to 76 +/- 9 L/1.73 m2/week. The supine position allowed the 25% Pip increment from 10.2 +/- 2.5 to 12.5 +/- 3.1 cm water, without any obvious clinical side effects. PMID- 9360698 TI - A comparison of double-cuffed with single-cuffed Tenckhoff catheters in the prevention of infection in pediatric patients. AB - Double-cuffed peritoneal catheters (DCCs) may be more effective at preventing penetrating infection than single-cuffed catheters (SCCs). The aim of this study was to see whether DCCs conferred any benefit in the pediatric population. Twenty consecutive SCCs inserted for chronic dialysis were compared with 20 subsequent DCCs. All catheters were inserted by a single operator (MAL). Outcome was assessed by the number of exit-site infections (ESIs) and episodes of peritonitis. There was no difference in the age or sex distribution of the groups, both having 50% of patients under 5 years. The SCCs were followed for 106 patient-months (1 still in situ) and the DCCs for 145 patient-months (11 still in situ). Peritonitis-related catheter loss was significantly more common with SCCs (9 vs 1, p < 0.01). S. aureus was a significantly more common cause of peritonitis in SCCs (10 vs 3, p < 0.03), although almost all ESIs were with this organism. The relative risk of S. aureus peritonitis with a SCC compared to a DCC was 2.077 (95% confidence interval, CI, 1.17-3.69), and the relative risk of catheter loss with peritonitis was 7.5 for SCCs (95% CI 1.14-49.6). In conclusion, double-cuffed peritoneal catheters are more effective than single cuffed catheters in preventing penetrating infection in infants and children. PMID- 9360699 TI - Is fibrin glue useful in preventing dialysate leakage in children on CAPD? Preliminary results of a prospective randomized study. AB - Children on continuous ambulatory peritoneal dialysis (CAPD) have a higher incidence of dialysate leakage than patients receiving cycler dialysis. To date, fibrin glue has been used to treat dialysate leakage but not as a method of prevention. Therefore, we conducted a prospective study in which 20 catheters were implanted in 19 children, with each catheter randomly assigned to either the treatment group (1 mL of fibrin glue added to peritoneal cuff suture) or the control group. There was no difference in mean patient age, elapsed time between catheter implantation and first catheter usage, and albumin concentration between the two groups. Dialysate leakage was detected in 4 patients in the control group, 3 of whom underwent early initiation of dialysis, but none of the patients in the treatment group (including 4 with early dialysis) had a similar problem. In summary, these preliminary data suggest that fibrin glue may be of benefit when applied at the time of catheter implantation. Further experience is necessary before this method can be routinely recommended. PMID- 9360700 TI - Staphylococcus aureus nasal carriage in children receiving long-term peritoneal dialysis. AB - The frequency of Staphylococcus aureus (SA) nasal carriage and the impact of antibiotic therapy remain undefined in children receiving long-term peritoneal dialysis (PD). We obtained a nasal culture for SA every 4-12 weeks in 21 children (mean age 7.03 +/- 5.8 years) receiving PD from January 1992 to August 1996 (total of 35.3 patient-years). In each case, SA nasal carriage (NSA+) was treated with intranasal mupirocin for 7 days. NSA+ was detected in 13 patients (61.9%) who received dialysis for 28.9 patient-years. Eight (61.5%) of 13 patients became NSA+ during the initial 3 months of dialysis. Seven (53.8%) of the NSA+ patients had 11 exit-site infections (ESI) and one episode of peritonitis (0.42 total infections/patient-year) due to SA. The 8 patients without SA nasal carriage (NSA ) received dialysis for 6.4 patient-years. None of the NSA-patients had an ESI or peritonitis with SA. Finally, the incidence of non-SA infections in the NSA+ and NSA- groups was not different (0.62 vs 0.31 total infections/patient-year, p > 0.05). In conclusion, there appears to be an association between SA nasal carriage and SA ESI in children on PD. The risk of SA peritonitis in NSA+ patients treated with mupirocin may be minimal. The risk of SA nasal carriage may increase with time on dialysis. PMID- 9360701 TI - "H" reflex as a measure of subclinical uremic polyneuropathy in children with chronic renal failure. AB - Uremic polyneuropathy (UPNP) is a serious complication of chronic renal failure (CRF) in adults; however, its prevalence is unknown in the pediatric population. An easy-to-perform maneuver for its detection in children is the evaluation of "H" reflex. The objective of this study was to validate the usefulness of the "H" reflex maneuver for the diagnosis of UPNP in pediatric dialysis patients for CRF. Thirty-seven CRF patients were paired with healthy controls by age and sex. The patients were being treated with dialysis or one of its variants. Information was obtained regarding diagnosis, duration, and control of dialysis. Neurological examination was performed, conduction velocities in sensory and motor nerves were measured, and "H" reflex elicited bilaterally. Peripheral polyneuropathy was determined by the presence of at least two nerves with alterations in latency and/or conduction velocities. It was found that 59.4% (22/37) of the children with CRF treated with dialysis developed UPNP, 17 with ambulatory peritoneal dialysis, and 5 with hemodialysis. There was no difference in diagnosis, duration of dialysis, or control of the same in these patients from other CRF patients who did not have UPNP. All patients were clinically asymptomatic. "H" reflex showed a sensibility of 44%, a specificity of 87%, a predictive value positive of 66%, and a predictive value negative of 76%, when measured to 28 msec. With a 30 msec duration specificity rises to 95%. UPNP presents asymptomatically in pediatric patients. "H" reflex is an adequate screening test for the selection of pediatric patients to be tested further. PMID- 9360702 TI - Comparison of the response to the recombinant vaccine against hepatitis B virus in dialyzed and nondialyzed children with CRF using different doses and routes of administration. AB - In patients with chronic renal failure (CRF), parenteral transmission of the hepatitis B virus (HBV) is common. The response to the recombinant vaccine is 50% 80% of seroprotection. Therefore, to improve seroprotection, different strategies such as dose augmentation, vaccination at the predialysis stage, subcutaneous application, and using interleukin were tried, with unsatisfactory results. In children, there are no studies demonstrating the efficacy of the vaccine. The aim of this study was to evaluate the efficacy of the recombinant vaccine in children with CRF, in late as well as early phases, through the quantification of antibodies against the surface antigen in response to different doses of the vaccine against HBV. There were 103 patients who were assigned to three groups: (1) 25 patients with CRF in the early phase (undergoing pharmacological treatment only); (2) 67 patients with CRF in the late phase (treatment with peritoneal dialysis or hemodialysis); (3) 11 patients with CRF in the early phase (undergoing low-dose pharmacological treatment only). The antibodies against the serum antigen (HBsAg) were measured by the aEIA method. Urea, creatinine, and creatinine clearance were measured at 0, 2, and 12 months. In our seroprotection results we observed that group 1 and 3 developed earlier seroconversion (50% first month). In patients undergoing dialysis the seroconversion happened in 91% at month 13, but with lower concentration than group 1 and/or group 3 (p < 0.05). In conclusion, there is a better response in predialysis patients. The levels of antibodies are similar in groups 1 and 3 (with small doses), which are similar to the complete doses for an efficient immunity in children with chronic renal failure. PMID- 9360703 TI - Stress and burden of care in families with children commencing renal replacement therapy. AB - A collaborative project was initiated in two pediatric centers to examine the long-term demands and outcomes in families with children commencing renal replacement therapy. Parents returned questionnaires on stress, anxiety, depression, information needs, and intrusion factors pre, at 3 months, 6 months, and annually. A burden of care assessment (BCA) for families was devised using a scoring system based on the domains of patient, sibling, parents, environment, demands of therapy, and dialysis/transplant factors. Team members also documented medical events and family contacts. In 2 years, 38 patients (26 male) were enrolled with an age range 0.2-18.5 years. Mean stress, anxiety, and depression scores were higher in mothers than fathers, and scores were higher in parents of patients > 10 years compared to the patient group < 10 years. In families with a high initial BCA score there was a positive correlation with maternal stress and anxiety scores. Patients from families with a low BCA score had better growth performance. Older children requiring renal replacement therapy may produce more stress and intrusion for parents than younger children. Burden of care assessments may be a useful means of predicting families who require greater support from the multidisciplinary team. PMID- 9360704 TI - dUTP pyrophosphatase as a potential target for chemotherapeutic drug development. AB - Aberrant dUTP metabolism plays a critical role in the molecular mechanism of cell killing induced by inhibitors of dihydrofolate reductase and thymidylate synthase. While considerable effort has been directed towards discovering new, more potent inhibitors of these two enzymes, little attention has been given dUTP pyrophosphatase (dUTPase)--the key modulator of cellular dUTP levels--as a potential target for chemotherapeutic drug development. Recent studies have provided evidence that dUTPase is vital for cellular and, in some cases, viral DNA replication. Furthermore, some retroviruses encode dUTPases--a fact which suggests that cellular dUTP metabolism may be more important than previously realized. Here, we briefly review current knowledge of cellular and viral dUTPases and discuss the potential of these enzymes as targets for cancer chemotherapeutic and anti-viral drug development. PMID- 9360705 TI - Retention of glycosyltransferases in the Golgi apparatus. AB - A number of Golgi glycosyltransferases has been cloned to date. They all are membrane proteins and share the same type II topology, but they do not possess an obvious sequence homology which would suggest a common Golgi retention signal. However, it was shown that the membrane-spanning domain and its flanking regions contain necessary and sufficient information for Golgi retention of these enzymes. Currently, two mutually complementary models have been proposed to explain the mechanism of Golgi retention of glycosyltransferases mediated by their transmembrane domain. The first model postulates the retention through oligomerization, which prevents enzymes from entering the transport vesicles. The second suggests that retention depends on the length of a membrane-spanning domain and thickness of the membrane along the Golgi complex. It has to be pointed out that neither the oligomerization nor the membrane thickness model alone can answer all questions and further work is still needed to elucidate the retention process of Golgi proteins. PMID- 9360706 TI - Characterization of the oligosaccharide component of arylsulfatase B from rat liver. AB - A glycan chain analysis of the total oligosaccharide pool derived from rat liver arylsulfatase B was carried out by. P4 Gel Permeation Chromatography and sequential exoglycosidase digestion. It was found that 71% of rat liver arylsulfatase B oligosaccharides were sialylated. The relative contribution of particular structures in the total glycan pool was as follows: sialylated biantennary complex type glycans with terminal galactose--65%, high-mannose type glycans--15%, biantennary complex type glycans with core fucose and terminal N acetylglucosamine--5%, O-linked oligosaccharides--3.5%. PMID- 9360707 TI - The phosphorylation sites of ribosomal P proteins from Saccharomyces cerevisiae cells by endogenous CK-2, PK60S and RAP protein kinases. AB - The phosphorylation sites of ribosomal acidic proteins (P proteins) from Saccharomyces cerevisiae were studied in vivo and in vitro by using CK-2, PK60S and RAP protein kinases. The three enzymes phosphorylate the last serine residues located in a highly conserved carboxyl end of the polypeptide chains. This was established by two-dimensional analysis of tryptic phosphopeptides from 32P labelled proteins YP1 alpha, YP1 beta, YP2 alpha and YP2 beta, and by kinetic studies of the protein kinases with synthetic peptides corresponding to the fragments of endogenous ribosomal acidic polypeptides. In experiments with both endogenous P proteins and synthetic peptides as substrates protein kinase PK60S demonstrated unusual substrate specificity. In contrast to CK-2 and RAP protein kinases, PK60S phosphorylates predominantly two of the four P proteins, YP1 alpha and YP2 beta, with kinetic constants dependent on the primary structure of the N terminal region of the polypeptide containing the target residue. The neutral amino acid, alanine, at position 3 in the peptide AAEESDDD (polypeptide fragments of YP1 beta and YP2 alpha) decreases the K(m) value more than 10-fold by comparison with the basic lysine residue at the same position in the peptide AKEESDDD (polypeptide fragments of YP1 alpha and YP2 beta). PMID- 9360709 TI - Synthesis of gamma-chaconine and gamma-solanine are catalyzed in potato by two separate glycosyltransferases: UDP-glucose:solanidine glucosyltransferase and UDP galactose:solanidine galactosyltransferase. AB - UDP-glucose:solanidine glucosyltransferase and UDP-galactose:solanidine galactosyltransferase from cytosol of potato sprouts were partially separated by Sephadex G-100 and Q-Sepharose chromatographies, proving the existence of different glycosylation systems in biosynthesis of alpha-chaconine and alpha solanine. PMID- 9360708 TI - N-acetylneuraminic acid, phosphate and thiol groups of pyruvate kinase isoenzymes from Morris hepatoma 7777 and normal rat liver. AB - The highest amount of N-acetylneuraminic acid (AcNeu) was found in pyruvate kinase isoenzyme L from normal rat liver (24 moles/mole of enzyme tetramer), with the highest electrophoretic mobility. On the other hand, isoenzyme M2 from Morris hepatoma 7777, with the lowest electrophoretic mobility, had the lowest AcNeu content (5 moles/mole of enzyme tetramer). This tumour isoenzyme M2 of pyruvate kinase was, however, characterised by the highest phosphate content (12 moles/mole protein), in comparison to isoenzyme L (3 moles/mole protein) or normal liver isoenzyme M2 (6 moles/mole protein). This could indicate a regulatory change caused by reversible enzyme phosphorylation and dephosphorylation or sialization and desialization. Despite these differences, the sum of the two negatively charged residues was lower in tumour pyruvate kinase isoenzyme M2, with the slowest migration rate, than in normal rat liver isoenzyme M2. Moreover, isoenzyme M2 from tumour material, in comparison with isoenzyme M2 from normal rat liver, had a twice as high content of thiol groups (20 moles/mole protein), especially of free and superficially located ones, than the isoenzyme M2 from normal liver (10 moles/mole protein). This may explain abnormal susceptibility of tumour isoenzyme M2 to stereospecific inhibition by exogenous L-cysteine, and indicate genetically dependent changes in amino-acid content of tumour enzyme which take place during cell tumourigenic transformation. PMID- 9360710 TI - Transformation of 1-O-(indole-3-acetyl)-beta-D-glucose into di-O-(indole-3 acetyl)-D-glucose catalysed by enzyme preparations from corn seedlings. AB - A new enzymatic activity, which catalyses formation in vitro of di-O-(indole-3 acetyl)-D-glucose from 1-O-(indole-3-acetyl)-beta-D-glucose has been found in extracts of Zea mays seedlings. The structure of di-O-(indole-3-acetyl)-D glucose, not as yet described, has been assigned by GC-MS, 1H NMR and ammonolysis. PMID- 9360712 TI - Modification of pre-mRNA splicing by antisense oligonucleotides. AB - Antisene oligonucleotides have been extensively studied as agents that inhibit the expression of undesirable genes in a sequence specific manner. Results reviewed in this article show that antisene oligonucleotides can also restore the expression of genes inactivated by mutations causing genetic diseases. In this novel application, antisene oligonucleotides block aberrant splice sites created by the mutations, forcing the spliceosomes to form at correct splice sites, thus restoring the proper splicing pathway and consequently the activity of the damaged gene. PMID- 9360711 TI - Expression, purification and kinetic properties of human recombinant phospholipase C delta 3. AB - To obtain sufficient quantities of pure phospholipase C delta 3 (PLC delta 3) necessary for structural and kinetic studies, cDNA of human fibroblast PLC delta 3 was cloned in the pPROEX-1 vector, expressed in E. coli cells as a (6 x His) fusion protein and purified to homogeneity. From 1 L of E. coli culture 8 mg of pure PLC delta 3 was obtained by a two step purification procedure, which includes phosphocellulose and Mono S cation exchange chromatography. The presence of His tag did not affect the catalytic and regulatory properties of PLC delta 3. The K(app) for PIP2 was 142 +/- 11 and 156 +/- 12 microM for His.PLC delta 3 and PLC delta 3, respectively. Recombinant PLC delta 3 showed an absolute requirement for Ca2+. Increasing the free Ca2+ concentration from 0.2 to 0.5 microM resulted in a sharp increase in enzyme activity. In comparison with human recombinant PLC delta 1 the delta 3 isoenzyme was more sensitive to low Ca2+ concentration. The Ca2+ concentration yielding maximal activation of PLC delta 1 and PLC delta 3 was 10 and 1 microM, respectively. The activity of PLC delta 3 was stimulated by polyamines and by basic proteins such as protamine, histone and mellitin. PLC delta 3 was activated most effectively by spermine and histone but the extent of this activation was lower than for PLC delta 1. The data presented indicate that the expression of PLC delta 3 in E. coli cells permits to obtain active enzyme. The catalytic and regulatory properties of PLC delta 3 are similar to those of PLC delta 1. PMID- 9360713 TI - The dynamic nature of plant mitochondrial genome organization. AB - The characteristic features of higher plant mitochondrial genomes: size, structure, recombination activity and evolutionary dynamics, are reviewed with the emphasis on the mitochondrial DNA (mtDNA) of Phaseolus vulgaris. Among all examined eukaryotic organisms, higher plants were found to contain the largest and most complex mitochondrial genomes. The plant mtDNA structure in vivo and mechanisms of evolution are controversial. We present the currently accepted models and how these models correspond to mitochondrial genomes of several common bean lines. PMID- 9360714 TI - Expression of the yeast NAM9 gene coding for mitochondrial ribosomal protein. AB - We studied expression of the NAM9 gene of Saccharomyces cerevisiae that was previously reported to code for a mitochondrial ribosomal protein. Increase in NAM9 gene dosage is accompanied by the increase in both mRNA and protein. The levels of the NAM9 transcript and protein are both reduced in cells growing on glucose as compared to cells growing on galactose as a carbon source. Nam9p accumulates to the same level in rho(o) and rho(+) cells. These results confirm previous data indicating diverse regulation of different mitochondrial ribosomal protein genes and suggest that expression of Nam9p is not co-ordinated with the expression of other mitochondrial ribosomal components. PMID- 9360715 TI - Nucleotide sequence of nuclear tRNA(Gly) genes and tRNA(Gly) pseudogenes from yellow lupin (Lupinus luteus): expression of the tRNA(Gly) genes in vitro and in vivo. AB - A nuclear DNA fragment (7.8 kb) from yellow lupin (L. luteus) was sequenced and shown to contain tRNA(Gly) (GGC) genes and tRNAGly (GGC) pseudogenes organized in three tandemly repeated units: of 2565 bp and 2564 bp, and one, truncated from its 3' end, of 1212 bp. Each unit contains an identical pair of a tRNA(Gly) gene and a pseudogene, both having the same polarity. The nucleotide sequence of the gene appears colinear to L. luteus cytoplasmic tRNA(Gly) (GGC) primary structure. All three genes are efficiently transcribed in HeLa-cell nuclear extract giving two primary transcripts. The main, longer primary transcripts have each an extremely long 3' trailer of about 100 nucleotides, the structure of which is specific only for tRNAGly genes and pseudogenes (80% homology) of the studied tandem (but not for other tRNA(Gly) genes of the yellow lupin genome) as it has been shown by Southern hybridization. This distinctive feature allowed to isolate putative tRNAGly precursor(s) encoded by at least one of the three tRNA(Gly) (GGC) genes from L. luteus seedlings. PMID- 9360716 TI - Molecular cloning and expression in Escherichia coli of a gene coding for bovine S100A1 protein and its Glu32-->Gln and Glu73-->Gln mutants. AB - Calcium binding S100A1 protein consists of two S100 alpha subunits. On the basis of sequence homology to other S100 proteins it is believed that the binding loops are formed by amino-acid residues 19-32 and 62-73 of S100 alpha polypeptide chain. In the oxidized form of the protein the subunits are linked covalently with each other by a disulphide bond between their Cys85 residues. A synthetic gene coding for bovine S100 alpha subunit was constructed and cloned into a derivative of pAED4 plasmid. The gene was expressed in Escherichia coli utilizing the T7 expression system. The expression products were purified and identified using mass spectrometry and by sequencing of their N- and C-termini. Three different forms (a, b, and c) of S100 alpha were produced: with the native sequence, with the initiator methionine at the N-terminus, and with an additional alanine at the C-terminus as well as with the initiator methionine. The material was partly oxidized. Interestingly, only the homodimers of a, b, and c species were formed. The total yield of the protein was about 50 mg/l of culture. Genes coding for Glu32-->Gln and Glu73-->Gln mutants of S100 alpha were obtained by site-directed mutagenesis and expressed in the same system. In both cases similar mixtures of oxidized and reduced a, b, and c species have been obtained. The total yield of E73Q mutant is similar to that of the native protein and that of E32Q lower by about a half. As expected, the mutants of S100 alpha subunits bind only one calcium ion. PMID- 9360717 TI - Determination of single monosugars bound to a peptide. AB - A method is described which allows detection and quantitative determination of single monosugar units bound O-glycosidically to a peptide. A glycoprotein or a glycopeptide is chemically degraded under the modified conditions of Carlson degradation (beta-elimination performed in weakly alkaline conditions in the presence of sodium borohydride). An aliquot of the neutralized reaction mixture, supplemented with an internal standard, is peracetylated, extracted and directly analyzed by g.l.c.-m.s. All the O-linked oligosaccharides split off from the peptide are derivatized, but under gas-liquid chromatography at 150-230 degrees C only monosugar peracetylated alditols reach the detector. By comparing the retention times of appropriate peaks with standards and by checking their mass spectra the monosugar alditols are unequivocally identified. The detectable amount of a reduced monosugar in the analyzed sample is about 0.3 microgram. Several glycoproteins were analyzed using this method. Free N acetylgalactosaminitol was detected in the degradation products of human glycophorin A and ovine submaxillary mucin, additionally free galactitol was detected in the degradation products of glycophorin. This result suggests that some single galactose units, O-glycosidically linked to the peptide are present in human glycophorin A. PMID- 9360718 TI - Immunochemical characterization of lipopolysaccharide from glucose-nonfermenting gram-negative clinical bacterial isolate. AB - A glucose-nonfermenting Gram-negative bacterial strain isolated from bronchofiberoscope used for examination of the patients suffering from pulmonary diseases was subjected to phenol-water extraction. Lipopolysaccharides (LPS) isolated from the water and the phenol phase differed in fatty acid composition. Both contained xylose, glucose, glucosamine and components typical for LPS, namely heptose, 3-deoxyoctulosonic acid (Kdo) and 3-hydroxymyristic acid. The presence of sphingosine in all LPS preparations classifies the strain to the genus Sphingomonas. PMID- 9360719 TI - The N-acetylgalactosamine and lactosamine specific lectin from Iris hybrida leaves. AB - The lectin isolated from the leaves of Iris hybrida binds specifically N-acetyl galactosamine and lactose. Its molecule consists of two identical subunits bound by disulfide bonds. The lectin is a glycoprotein containing about 12% of sugars. It binds asialoglycoproteins containing complex type sugar chains. The binding is reduced by half at the concentration of 0.15 to 0.40 mM of the galactose containing disaccharides irrespectively to a type of galactose isomer. This indicates rather broad specificity of I. hybrida leaf lectin. PMID- 9360720 TI - Studies on the nature of genotoxic and cytotoxic effects induced by hydralazine. AB - The nature of genotoxic and cytotoxic effects induced by hydralazine was analyzed taking into account possible protection of cells by catalase, superoxide dismutase and dimethyl sulfoxide. For the experiments designed to evaluate the influence of scavengers on the genotoxicity expressed as the SOS induction factor the E. coli PQ37 strain was used. The cytotoxic effects were investigated in V3 cells cultured in vitro. The genotoxicity and cytotoxicity of hydralazine were suppressed by catalase in a dose-dependent manner but they were enhanced by superoxide dismutase. No protective effect of dimethyl sulfoxide was observed. Our results indicate that H2O2 plays an essential role in the genotoxicity and cytotoxicity of hydralazine. PMID- 9360721 TI - Effect of high temperature treatment of Vicia faba roots on the oxidative stress enzymes in leaves. AB - The following types of superoxide dismutase (SOD) have been found in the leaves of Vicia faba: one isoenzyme of Mn-SOD and four isoenzymes of Cu/Zn-SOD. The treatments of roots with boiling water caused an increase of SOD activity in the leaves. The highest increase was measured after 5 s of the treatment. It was accompanied by a significant increase in catalase activity. Analysis of cell fractions' revealed an increase of SOD activity in the plastids and mitochondria isolated from the leaves of those plants whose roots were heat-treated. However, there was no distinct change of SOD activity in the cytosolic fraction. The possibility of an electric wave intervention inducing oxidative stress in the leaves is discussed. PMID- 9360722 TI - Ketone bodies activate gluconeogenesis in isolated rabbit renal cortical tubules incubated in the presence of amino acids and glycerol. AB - In isolated rabbit renal kidney-cortex tubules 2 mM glycerol, which is a poor gluconeogenic substrate, does not induce glucose formation in the presence of alanine, while it activates gluconeogenesis on substitution of alanine by aspartate, glutamate or proline. The addition of either 5 mM 3-hydroxybutyrate or 5 mM acetoacetate to renal tubules incubated with alanine + glycerol causes a marked induction of glucose production associated with inhibition of glutamine synthesis. In contrast, the rate of the latter process is not altered by ketones in the presence of glycerol and either aspartate, glutamine or proline despite the stimulation of glucose formation. Acceleration of gluconeogenesis by ketone bodies in the presence of amino acids and glycerol is probably due to (i) stimulation of pyruvate carboxylase activity, (ii) activation of malate-aspartate shuttle as concluded from elevated intracellular levels of malate, aspartate and glutamate, as well as (iii) diminished supply of ammonium for glutamine synthesis from alanine resulting from a decrease in glutamate dehydrogenase activity. PMID- 9360723 TI - Specificity of the tonoplast transport of the oleanolic acid monoglycosides in the vacuoles from Calendula officinalis leaves. AB - The specificity of two separate tonoplast permeases transporting oleanolic acid glycosides was investigated in vacuoles isolated from leaf protoplasts of marigold (Calendula officinalis) with the use of chemically synthesized analogs. The results indicate that the proper structure of both parts of oleanolic acid monoglycoside, i.e. aglycon and the sugar moiety, are required for binding to a specific tonoplast carrier. PMID- 9360724 TI - Activity of liver proteases in experimental methanol intoxication. AB - Intoxication of rats with methanol (1.5 and 3.0 g/kg body weight) led to a significant, time- and dose-dependent decrease in the activities of cathepsins A, B and C, while the activity of cathepsin D was unaffected. The decrease was associated with a different partial release of individual cathepsins to the post lysosomal fraction. PMID- 9360725 TI - Tumor cell N-glycans in metastasis. AB - Metastasis accounts for most of deaths caused by cancer. The increasing body of evidence suggests that changes in N-glycosylation of tumor cell proteins such as increased branching, increased sialylation, polysialylation, decreased fucosylation, enhanced formation of Lewis X and sialyl Lewis X antigens are among important factors determining metastatic potential of tumor cell. Most of the adhesion proteins, e.g., integrins, members of immunoglobulin superfamily, and cadherins are heavily N-glycosylated. The other proteins involved in adhesion, like galectins and type-C selectins, recognize N-glycans as a part of their specific ligands. In this review we focus on recent reports concerning the contribution of N-glycosylation of tumor cell adhesion molecules and some selected membrane proteins in the tumor invasion and metastasis. PMID- 9360726 TI - Adenosine deaminase activity in blood of patients with stable angina pectoris. AB - The activity of adenosine deaminases (EC.3.5.4.4) in granulocytes and lymphocytes of patients with stable angina pectoris was lower by about 27% and 24%, respectively as compared with control group, whereas these values in erythrocytes and blood plasma were at the normal level. PMID- 9360727 TI - Weapon-carrying and youth violence. AB - Weapons, and firearms in particular, are widely available in the United States and are at the heart of youth violence. Many schools and communities throughout the nation have identified weapon-carrying among youth as a substantial health, educational, and social problem. In fact, one of the national health objectives for the year 2000 is to substantially reduce the incidence of weapon-carrying among adolescents. This paper reviews the prevalence of weapon-carrying by youth, reasons they carry weapons, ways that firearms are obtained, firearms and violence (especially youth violence), and the controlling of weapons in schools. PMID- 9360728 TI - Adolescent same-sex and opposite-sex best friend interactions. AB - In the present study, 48 high school juniors selected their best same-sex and opposite-sex friends for a videotaping of 10-minute face-to-face interactions together. Females felt more comfortable during same-sex interactions than during opposite-sex interactions, and they rated their same-sex partners more positively than did males. Although second-by-second codings of the videotapes yielded no group differences on the percentage of time the dyads were in interested or animated states, females were in more playful states during their same-sex interactions and males were more playful during their interactions with females. PMID- 9360729 TI - Project Support: engaging children and families in the educational process. AB - The literature on dropout prevention reveals that a triumvirate of support--from the family, the school, and the community--is necessary to engage children in the educational process. This paper describes Project Support, a federally funded five-year program for at-risk youths that focused on alcohol, drug, and dropout prevention in four low-income, high-minority public school districts in the suburbs of New York City. Of several avenues taken, two were very effective: a school-based mentoring program designed for middle school students and the Outdoor and Environmental Education program that took place during summers and intermittently throughout the school year. The sense of achievement, bonding, and success experienced by participants was acknowledged by administrators, evaluators, parents, and other observers. PMID- 9360731 TI - Domain-specific gender comparisons in identity development among college youth: ideology and relationships. AB - Gender comparisons were conducted in six social domains of identity development on 210 college students: occupation, religion, politics, dating, sex roles, and friendship. The identity research literature often combines domains to create more global estimates of identity development. Such an approach may obscure differences among the domains, each of which may have different implications for different societal contexts, and for males and females. Analyses were made for each domain, and for the combined ideological, interpersonal, and overall domain scores. Several gender differences were apparent when domain-specific analyses were examined. Males were more likely to explore and commit in politics, whereas females were more likely to explore in sex roles and to commit in religion and dating. In politics, fewer males were in the diffused status; in contrast, for dating and sex roles, there were fewer females in the diffused status. However, when combined scores were examined, there were no gender differences in identity status. The results suggest that some gender differences still remain in specific domains. The utility of including domain-specific analyses is suggested when gender comparisons are examined. Regardless of gender, more youth were diffused in political identity than in any other domain, suggesting political apathy among today's college youth. PMID- 9360730 TI - Instruments to measure social support and related constructs in pregnant adolescents: a review. AB - This review examines some of the key issues related to measuring social support and identifies 28 instruments which have been used in research with pregnant adolescents. The major external and internal variables that affect social support for pregnant adolescents are defined. Relevant questions are offered to guide the researcher in the choice of a social support instrument, and the 28 social support instruments are described by author, availability, length and item type, psychometric properties, and selected references and notes. Although not an exhaustive list, these 28 instruments are representative of the broad spectrum of measurement tools available which were chosen because they have been used in a variety of social support research endeavors. PMID- 9360732 TI - Nuances before dinner: exploring the relationship between peer counselors and delinquent adolescents. AB - This paper details the peer counselor-client relationship as it occurs--in vivo- from the point of view of a participant observer. The relationship is viewed through two clinical lenses: one developmental, informed by self psychology (H. Kohut) and object relations theory (D. W. Winnicott), and one technical (Bibring's five therapeutic intervention principles). Peer counselors are seen as transitional objects who can both meet and interpret clients needs. Case material is presented. PMID- 9360733 TI - Adolescent male athletes: body image, diet, and exercise. AB - The purpose of this study was to investigate and compare body image concerns, attitudes toward eating/weight control, and reasons for exercising between two groups of adolescent male athletes--football players (N = 44) and cross-country runners (N = 30). Subjects responded to surveys covering eating attitudes, weight concerns, physical traits, perceived and ideal body shape/size, and reasons for exercising. Significant differences were noted: Football players reported a more positive body image; cross-country runners indicated a greater degree of body dissatisfaction, more disordered eating patterns, and a greater degree of concern for weight control which identified this group as one in need of increased health education. PMID- 9360734 TI - The influence of fashion magazines on the body image satisfaction of college women: an exploratory analysis. AB - This study examined the impact of exposure to fashion magazines on women's body image satisfaction. Participants were 39 undergraduate women, randomly assigned to two experimental conditions: half viewed fashion magazines prior to completing a body image satisfaction survey, and the remaining half, news magazines. Mean height and weight did not differ for the two groups. As hypothesized, women who viewed fashion magazines preferred to weigh less, were less satisfied with their bodies, were more frustrated about their weight, were more preoccupied with the desire to be thin, and were more afraid of getting fat than were their peers who viewed news magazines. PMID- 9360735 TI - Weight, weight-related aspects of body image, and depression in early adolescent girls. AB - This investigation assessed the hypothesis that early adolescent girls with more negative weight-related body images would report higher levels of depressive symptoms. The Beck Depression Inventory was administered, and measures of objective weight and four dimensions of weight-related body image were obtained: self-reported weight, subjective classification of weight from very underweight to very overweight, satisfaction with weight, and concerns about weight. The results indicated that the more subjective and personal measures of weight related body image discontent--weight dissatisfaction and weight concerns--were associated with increased depressive symptoms, even controlling for objective weight status. These results are discussed in relation to the ontogenesis of body image and the place of body image in personality and the development of depression. PMID- 9360737 TI - Co-victimization among African-American adolescents. AB - The level of violent acts witnessed by African-American adolescents continues to be a major problem. For example, in a single southwest Michigan school system, 331 students were reprimanded for battery of other students, 69 for battery of employees, 150 for possession of a knife, 117 for possession of a gun, and 73 students for use of dangerous weapons. This review of the literature explores the general concept of co-victimization and its impact on African-American adolescents, and briefly reviews supporting social learning theory. PMID- 9360736 TI - Treating powerless minorities through an ecosystem approach. AB - An ecological approach to social work practice for a minority based on an ecosystem-oriented assessment-intervention model is presented. Strengths and limitations of the ecological perspective for practice are emphasized (in the context of power dynamics). A case study is presented. PMID- 9360738 TI - Adolescent mothers' self-esteem and role identity and their relationship to parenting skills knowledge. AB - The purpose of this study was to investigate the relationship between the adolescent mother's self-esteem and her knowledge of parenting skills. Erikson's psychosocial theory provided the basis for the general hypothesis that the adolescent mother's global self-esteem will correlate with her parenting skills knowledge. The findings reported here support the conclusion that self-esteem is a good indicator of the adolescent mother's parenting. There were significant correlations between the mother's baseline self-esteem and her knowledge about role reversal, empathy, developmental expectations, and corporal punishment. The data also supported the hypothesis that adolescent self-esteem is developmentally continuous. Using Erikson's theory, it was argued that the adolescent mother's parenting is at risk if she has not had the opportunity to achieve her role identity, which is a prerequisite for the parenting stage of generativity. PMID- 9360739 TI - Street youth, their peer group affiliation and differences according to residential status, subsistence patterns, and use of services. AB - This study characterizes subcultural differences within an inner-city street youth population. Variations in residential status, subsistence patterns, and service utilization according to peer group affiliation were explored. A brief structured interview was administered to 752 youth, ages 12 to 23 years, who had been living on the streets for two or more consecutive months, or who were fully integrated into the "street economy." Subjects were recruited for the study using a stratified probability sampling design, with 30% recruited from community-based service sites and 70% from street locations and at natural "hang-outs." Five street youth groups were identified: "punks/skinheads," "druggies," "hustlers," "gang members," and "loners." The results demonstrated unique patterns with respect to places stayed/slept, means of financial support and economic subsistence, and use of available services according to peer group affiliation. The implications of these findings and recommendations for future research and service provision are discussed. PMID- 9360740 TI - The contribution of self-concept in the etiology of adolescent delinquency. AB - Self-concept was related theoretically with delinquency in the first two decades following World War II. Research in that period produced encouraging results, but only a paucity of empirical work on the relationship between self-concept and delinquency appears to have been done between the mid-1970s and early 1990s. This study utilized the Tennessee Self-Concept Scale to examine 230 adolescents from Australian high schools and from institutions incarcerating young offenders. They were categorized as nondelinquents, noninstitutionalized delinquents, and institutionalized delinquents. Differences were evident in the total and subscale scores of nondelinquents as compared with their delinquent counterparts. The implications of the results in the context of delinquency theories and for dealing with delinquent adolescents are discussed. PMID- 9360741 TI - Psychological determinants of idolatry in adolescents. AB - The self-esteem and fear of negative evaluation of 77 fan-club members age 16 or below and 128 age-equivalent secondary school students who had never joined a fan club were investigated. Consistent with common observations, fan-club respondents were mostly females. Significant differences were found between the two samples. Logistic regression analysis showed that being a fan-club member was associated with poor self-esteem and strong fear of negative evaluation, while the bias toward females in the fan-club sample could be attributed to the effects of these two variables. PMID- 9360742 TI - The effect of a physical activity intervention package on the self-esteem of pre adolescent and adolescent females. AB - The purpose of this study was to examine the effects of a physical activity intervention package on the self-esteem of pre-adolescent and adolescent females. The package involved three components: physical activity, education and self report. Subjects (N = 181) were pre-, early-, and middle-adolescent girls ranging in age from 9 to 16 who were enrolled in an independent school. An experimental pre-test/post-test design which involved two independent variables (intervention package and age group), each with three levels, was used. Self-esteem was measured with the Self Description Questionnaire I and II (Marsh, 1988). Results indicated that low self-esteem individuals benefitted from the intervention. However, statistically significant results were limited to the younger age group. PMID- 9360743 TI - Victim awareness programs for delinquent youths: effects on moral reasoning maturity. AB - The influence of Victim Awareness Program (VAP) attendance on the sociomoral reasoning maturity of juvenile delinquents was investigated. Subjects were inmates (aged 14-18 years) of two youth secure-care centers in Adelaide, South Australia. The treatment group (n = 23) attended sessions at which victims of crime and/or representatives from agencies closely involved with victims spoke about crime from the victims' perspective. Participants were assessed using the Sociomoral Reflection Measure-Short Form both before and after the program. Following the program, the treatment group recorded a significant increase in its mean Sociomoral Reflection Maturity score. No-treatment control subjects (n = 15) from the same centers failed to show any significant change at retest. Previous studies have found improvements in knowledge and attitudes toward victims following attendance at VAPs. Results here extend those findings to include positive change in sociomoral reasoning maturity--a variable that is empirically known to be related to prosocial behavior among adolescents. PMID- 9360744 TI - Women's perceptions of the adolescent experience. AB - Two focus groups of culturally and racially diverse middle-class women were used to examine the transitional process from their pre-adolescence through adolescence, and the issues, consequences, and coping strategies that emerged during this pivotal time in their lives. Changes in self-confidence, issues about body image, boys' sexual advances, and changes in parental relationships and friendships were pressures that had an impact on their adolescent years. Suggestions are made for future research. PMID- 9360745 TI - Body image in adolescence: cross-cultural research--results of the preliminary phase of a quantitative survey. AB - This preliminary phase of a quantitative research had two main objectives: to identify the emotional and relational components of body image in adolescents, and to determine whether the experience of body changes is dependent upon individuals' context. Two samples of adolescents, both 13 to 17 years of age, who were healthy, middle- or upper middle-class, and randomly chosen, participated in the study. Subjects were 80 French adolescents (40 boys and 40 girls) from a center for preventive medicine, and 60 American adolescents (30 boys and 30 girls), from a suburban high school. Thorough individual interviews were conducted with these adolescents on the basis of a precise interview guide in order to determine their perceptions, attitudes, and beliefs about body image. A thematic analysis of the content of these recorded interviews revealed the differences between adolescents from the two countries. I was found that the main cultural differences were based on the belief that the real body and the ideal body coincide, and on the way physical appearance is included in the diversity of relational experiences. Gender differences were shown to be centered more on the level of control of body changes and on self-assessment modes; the signs of a failing or troubled body image may find their origin on an individual level, in the particularities of the family and parental language about the body, and on a collective level in the social representation of the body. The consequences of these symbolic representations on the adolescents' body image and attitudes toward their own health, are presented and discussed. PMID- 9360746 TI - DNA immunization: a novel approach to allergen-specific immunotherapy. PMID- 9360747 TI - Quality of life in adults and children with asthma and rhinitis. AB - Many clinicians now recognize the importance of incorporating an assessment of health-related quality of life (HRQL) into their clinical studies and practice. Conventional clinical measures provide valuable information about the status of the affected organ system, but they rarely capture the functional impairments (physical, emotional, and social) that are important to the patients in their everyday lives. In order to obtain a complete picture of a patient's health status, both the conventional clinical indices and the patient's HRQL must be measured. Both adults and children with asthma and rhinitis are distressed by the symptoms, and they are limited in their day-to-day activities such as sports, work or school work, and participation in other activities with friends. In addition, both adults and children experience emotional strain as a result of both conditions. Disease-specific HRQL questionnaires have been developed and validated for both adults and children with asthma and rhinitis. These questionnaires have good measurement properties and validity and can be used in both clinical trials and clinical practice to assess the impact of the condition on a patient's life. Since one of the aims of treatment is to ensure that patients benefit from it, an essential component of clinical assessment should be an evaluation of HRQL. PMID- 9360748 TI - Influence of maternal infections with viral agents or Toxoplasma gondii during pregnancy on fetal IgE production. AB - The importance of maternal infections with Toxoplasma gondii, cytomegalovirus (CMV), Parvovirus B19, respiratory syncytial virus (RSV), and influenza A and B on fetal IgE synthesis was studied in 153 pregnant women. No case of specific IgM activity or viral DNA in cord blood, indicating a congenital infection, was found. From gestational week 15 to delivery, maternal IgG-Ab seroconversion to Parvovirus B19, RSV, influenza A, or influenza B occurred in 47 women. At delivery, serologic signs of past infection with T. gondii were observed in 29 (19%) women, and the corresponding figure for CMV was 117 (77%). The number of women with positive IgG seroconversion during pregnancy or positive IgG-Ab activity toward the studied infectious agents at delivery did not differ significantly among infants with an increased (> or = 1.3 kU/l; n = 51) or with an undetectable (< 0.1 kU/l; n = 102) cord-blood IgE level. These results show that genetic and other environmental factors probably have a greater influence on fetal IgE synthesis than do maternal infections during pregnancy. PMID- 9360749 TI - Recidivous acute urticaria caused by Anisakis simplex. AB - This study aimed to determine the cause of acute recidivous urticaria in patients who usually eat fish or other seafood. Twenty-five patients were studied. The skin prick test with larval Anisakis simplex extract was performed; total and specific IgE against A. simplex was measured with the CAP System; specific antibodies to A. simplex were determined by ELISA; and immunorecognition patterns of the sera were studied by Western blot. Nineteen patients showed specific IgE to A. simplex, but specific IgE to Ascaris was demonstrated in only two patients. No patients reacted to Toxocara canis or Echinoccocus granulosus antigens with the same test. The skin prick test was positive in 16 patients, in two of them persisting for 48 h. Five patients showed neither skin reaction nor specific IgE to A. simplex. Sera showed specific immunoglobulin levels against A. simplex larval crude extract, by both ELISA and Western blot. Likewise, specific immunoglobulin levels against excretory-secretory antigen were also measured by ELISA. Only one patient showed sensitization to fish. A. simplex was found to be the main cause of acute recidivous urticaria in patients who usually eat fish and are not sensitized to it. PMID- 9360750 TI - Priming and inducing effects of interleukin-3 on histamine release from cord blood basophils. AB - The effect of interleukin-3 (IL-3) on histamine release from cord and adult blood basophils were evaluated. Leukocyte suspensions, obtained from adult patients with respiratory allergy (n = 15), normal adult subjects (n = 15), and neonates with (n = 15) and without (n = 19) atopic disposition, were stimulated with anti IgE, fMLP, and IL-3. IgE-mediated histamine release was significantly higher in adult patients, either allergic or normal, than in neonates with or without atopic disposition. A trend toward higher fMLP-induced histamine release was found in allergic adult subjects. IL-3 had a weak direct histamine-releasing activity in allergic adult subjects and in neonates, but not in normal adult donors. A significant enhancing effect of IL-3 on histamine release induced by anti-IgE was observed in neonates with and without atopic disposition and in normal adult subjects, but not in atopic adult patients. IL-3 exerted a priming effect also when basophils were stimulated with fMLP, without any significant difference between neonates and adult subjects. Passive sensitization with IgE rich serum resulted in a significant increase in anti-IgE-induced, but not in IL 3-induced, histamine release from cord-blood basophils. In conclusion, IL-3 primes cord-blood as well as adult blood basophils for a consecutive anti-IgE- or fMLP-induced histamine release and its activity is not limited by the low density of membrane IgE in cord-blood basophils. PMID- 9360751 TI - Predictors of early- and late-phase reactions to bronchial allergen challenge. AB - The influence of inhaled steroids and predictive factors on the response to bronchial allergen challenge (BCA) was evaluated in 80 asthmatics allergic to Dermatophagoides pteronyssinus (Der p). All underwent BCA with Der p and measurement of early (EAR) and late asthmatic reaction (LAR). The cumulative dose of allergen producing 20% fall in FEV1 in the EAR (PD20) was calculated. Bronchial histamine provocation, conjunctival provocation test (CPT), and skin prick test with Der p extract were performed. Specific IgE to Der p in serum (RAST), blood eosinophil (EOS) count, serum eosinophil cationic protein, and eosinophil protein X were measured. Thirty patients (38%) were treated with inhaled steroids. All patients had at least a 20% fall in FEV1 in EAR. Some 42% of nonsteroid- and 33% of steroid-treated patients had LAR with fall in peak flow of at least 20%. For patients not treated with steroid, 35% of variation in PD20 was explained by RAST and histamine reactivity, and 53% of variation of observed PD20 could be predicted. The baseline FEV1, EOS, and EAR explained 28% of variation in LAR, and 28% of variation in observed LAR could be predicted. For patients treated with steroids, 38% of variation in PD20 was explained by EOS and histamine reactivity, and only 18% of variation of observed PD20 could be predicted. For patients treated with steroids, it was impossible to predict LAR. We conclude that to achieve a quantitative estimation of allergen-specific EAR and LAR, BCA cannot be replaced by the tests used in this study. Treatment with inhaled steroids modifies the response to BCA, making quantitative prediction of EAR less accurate and prediction of the magnitude of LAR impossible. PMID- 9360752 TI - Eosinophilic pneumonia caused by Alternaria alternata. AB - We describe a patient who presented with hypoxemia and diffuse bilateral pulmonary infiltrates. The diagnosis of eosinophilic pneumonia was confirmed by bronchoalveolar lavage and transbronchial lung biopsy. The remarkable characteristic was reappearance of the symptoms on the patient's return home, suggesting the existence of etiologic agents in his house. An environmental survey of the patient's house yielded Alternaria alternata. A high titer of anti A. alternata antibody (IgG) was detected in his serum, and the inhalation bronchoprovocation test with A. alternata antigen was positive. This case indicates that A. alternata is a probable cause of eosinophilic pneumonia. PMID- 9360753 TI - Successful administration of cytarabine after a previous anaphylactic reaction. AB - Cytarabine (Cyt) is an antimetabolite used primarily in the treatment of leukemia, and both immediate and delayed hypersensitivity reactions have been reported. We studied a 9-year-old girl with lymphoblastic leukemia, who developed three anaphylactoid reactions during Cyt treatment courses over a 1-year period. Three years later, Cyt was required again. Although a skin test was negative to Cyt at the concentration of 4 micrograms/ml, we decided on placebo-controlled administration of the drug. The Cyt was well tolerated, and urine values of N methylhistamine showed no important variations throughout this period compared to those during the placebo administration. Skin tests carried out 14 days after the study were positive at the concentration of 4 micrograms/ml. The history of different episodes of allergic reactions to Cyt, the last one being the most severe, indicated the possible participation of an immediate hypersensitivity phenomenon, but because no studies had been carried out initially, we could not establish the presence of IgE antibodies. These results indicate that good tolerance existed after the control administration procedure. The long interval, 3 years, between the allergic episode and our protocol and the appearance of a positive skin test 14 days after the protocol indicated that the subject had lost sensitivity and become resensitized after the controlled administration procedure. PMID- 9360754 TI - Reduction of Staphylococcus aureus in atopic skin lesions with acid electrolytic water--a new therapeutic strategy for atopic dermatitis. AB - The subjects studied were 22 pediatric patients newly diagnosed with atopic dermatitis (AD); 11 were treated with acid electrolytic water (AEW), which has a strong bactericidal activity (AEW group), and the other 11 with tap water (placebo group). AEW or tap water, 1 ml/cm2 (body surface area), was sprayed on their skin lesions with a spray gun each twice a day for a week. There were no significant differences between the two groups in regard to sex, age, serum IgE, peripheral eosinophil counts, grading scores of AD, and duration of AD. The study was designed as a randomized, placebo-controlled, double-blind clinical trial. Colony counts of Staphylococcus aureus on skin lesions in the AEW group, both 3 min after spraying (P < 0.05) and after 1 week of skin treatment (P < 0.01), were significantly decreased as compared with colony counts before treatment, while there was no significant difference in the placebo group before and after treatment. Grading scores of AD also decreased in the AEW group (P < 0.01), but not in the placebo group. Both the subjects' guardians' evaluation and a referee physician's evaluation of treatment effect were significantly higher in the AEW group than in the placebo group (P < 0.01). AEW may be potentially effective in preventing a staphylococcal chronic inflammation in AD because of its strong bactericidal activity. PMID- 9360755 TI - IgA antiendomysium antibodies in human umbilical cord sections as a screening test in relatives of patients with celiac disease. AB - We performed the serum IgA antiendomysium antibody (EmA) assay by indirect immunofluorescence on human umbilical cord sections in 86 subjects with celiac disease, in 187 first-degree relatives of such patients, and in a control group of 68 unrelated subjects, to investigate the suitability of the method in the screening of populations at risk of gluten sensitivity. Conventional EmA assay using monkey esophagus sections was performed in parallel experiments. The results obtained showed a perfect correlation between the two methods. All the celiac patients and none of the controls were positive for EmA. EmA positivity was also observed in 11 apparently healthy relatives: intestinal biopsy performed in five of them invariably showed villous atrophy and increase of mucosal lymphocytes. Taking into account the low cost of EmA assay on human umbilical cord, especially when compared to monkey esophagus sections, the method is probably suitable and effective in identifying latent, asymptomatic gluten sensitivity in at-risk populations. PMID- 9360756 TI - Reduction of soluble ICAM-1 levels in nasal secretion by H1-blockers in seasonal allergic rhinitis. AB - ICAM-1, a transmembrane glycoprotein promoting adhesion in immunologic and inflammatory reactions, was found to be increased on nasal epithelial cells of patients with allergic rhinitis. Loratadine, an H1-blocker, was found to reduce in vitro the expression of ICAM-1 on nasal epithelial cells. A double-blind, parallel-group study was carried out during the pollen season to compare the effect of two H1-blockers, cetirizine (10 mg OD) and loratadine (10 mg OD), on the release of soluble ICAM-1 in nasal secretions. A group of untreated patients was used as a control group. sICAM-1 was measured by enzyme immunoassay before and after 2 weeks of treatment. Symptoms were significantly decreased in the actively treated groups. sICAM-1 levels were unchanged in the control group but were significantly reduced in the two treated groups (P < 0.015, Wilcoxon's W test). This study shows that two H1-blockers, loratadine and cetirizine, have a similar effect on sICAM-1 released in nasal secretions during the pollen season. PMID- 9360757 TI - Aerobiologic particle sampling by a new personal collector (Partrap FA52) in comparison to the Hirst (Burkard) sampler. AB - A new personal portable sampler of biologic particles (Partrap FA52, Coppa, Biella, Italy) was used for pollen sampling in comparison with Hirst's (Burkard) fixed device. The aerobiologic samplings were carried out simultaneously outdoors with the two devices coupled on the same axis, during the daytime of 10 dry, nonconsecutive spring days. The total amount and the percentages of the pollens most often trapped by the two collectors were compared by Student's t-test for paired samples. The Partrap FA52 showed a highly significant efficacy, quite comparable to that of the Burkard device, in pollen trapping for both the total number (P < 0.0001) and the percentages of Parietaria (P < 0.0001), pine (P < 0.002), and grass (P < 0.0001) pollens. Therefore, Partrap FA52 proved to be highly effective in obtaining quantitative and qualitative aerobiologic samples in comparison with the commonly used fixed samplers. PMID- 9360758 TI - Correlations between skin prick tests using commercial extracts and fresh foods, specific IgE, and food challenges. AB - The skin prick test is the most widely used test for detecting IgE-mediated food hypersensitivity. Our study aimed to define firstly the correlations between results obtained with prick tests using commercial extracts and fresh foods, and secondly the correlations between these results and those obtained with labial and/or oral challenge. We compared the wheal diameters read at 15 min with commercial extracts and fresh foods, for four foods, in 430 children with suspected food allergy. For cow's milk, wheal diameters were larger with commercial extracts, but the difference was not significant. Conversely, wheal diameters were significantly larger with fresh foods for the other food allergens. Skin prick tests were positive in 40% of cases with commercial extracts and in 81.3% with fresh foods. The overall concordance between a positive prick test and positive challenge was 58.8% with commercial extracts and 91.7% with fresh foods. These results indicate that fresh foods may be more effective for detecting the sensitivity to food allergens. Fresh foods should be used for primary testing for egg, peanut, and cow's milk sensitivity. PMID- 9360759 TI - The inverse relationship between tuberculin responses and atopic disorder. PMID- 9360760 TI - Allergy to maggots. PMID- 9360761 TI - Carbamazepine-induced fixed drug eruption. PMID- 9360762 TI - Perennial and seasonal rhinitis in Ankara, Turkey. PMID- 9360763 TI - Diagnosis of latex allergy. PMID- 9360764 TI - Evaluation of a nutritional strategy to increase ovulation rate in merino ewes mated in late spring-early summer. AB - A nutritional strategy for increasing ovulation rate in Merino ewes mated in late spring-early summer was evaluated on two commercial farms. The strategy used the 'ram effect' to induce oestrus in seasonally anoestrus ewes and supplementary feeding of lupin grain six days prior to oestrus to increase ovulation rate. Ewes that had been isolated from rams for 6 weeks were exposed to vasectomised rams for 2 weeks and then mated to fertile rams for 6 weeks. Feeding 500 g lupins/head/day for 14 days commencing 12 days after the introduction of vasectomised rams, increased the number of ovulations from 126 to 146 per 100 ewes exposed to rams (P < 0.05). This increase was reflected in an improvement in fecundity (lambs born per ewe lambing; P < 0.05) but not fertility (ewes lambing per ewe mated to rams). Net reproductive performance (the product of fertility, fecundity and lamb survival) was increased by 11 lambs weaned per 100 ewes exposed to rams due to lupin supplementation at mating. PMID- 9360765 TI - Effects of dexamethasone administration to diestrus cows on systemic progesterone, estrogen and uterine cyclooxygenase production. AB - Parenteral administration of dexamethasone to diestrus cattle can extend the length of the natural estrous cycle. In mice, dexamethasone has been shown to inhibit production of the second isozyme of the cyclooxygenase (COX) enzyme (a rate limiting enzyme in prostaglandin formation). Therefore, the purpose of this study was to determine the effect of dexamethasone on estrous cycle length and COX-1 and -2 production by the uterine endometrium of cyclic cattle. Nine crossbred beef cows that exhibited two previous normal estrous cycles were randomly assigned to two treatments; a control group administered intramuscular injections of vehicle, and a dexamethasone group administered 8 mg of dexamethasone (Azium, Schering Corp., Kenilworth, NJ). Both groups received twice daily injections on day 13-22 of the treatment cycle. Uterine endometrial biopsies were collected on days 16, 19 and 22 of the treatment cycle. Blood samples were collected daily on day 13-22 of the treatment cycle for plasma progesterone and estradiol concentrations. PMID- 9360766 TI - Endocrine changes during early pregnancy in the alpaca. AB - Plasma concentrations of progesterone, 15-keto-13, 14-dihydroprostaglandin F2 alpha and oestradiol-17 beta were monitored during early pregnancy in five alpacas. Heparinized blood samples were obtained every 15 min during a 4 h period (0800 to 1200 h) from day 8 to day 13 postmating. Mean plasma concentrations of oestradiol-17 beta decreased close to the detection limit of the assay from day 8 until days 10-11, whereupon they increased again until day 13. A rapid decline in progesterone concentrations occurred after day 8 postmating. All progesterone values registered after day 10 were significantly lower than those registered on day 8. After day 9 postmating, prostaglandin metabolite peaks were detected in all animals, indicating a temporal relationship between the progesterone decline and PGF2 alpha pulsatile release. The number of peaks detected during the 4-h period, monitored on each of the 5 days (day 9 to day 13), ranged from two to four in different animals. The analysis of the prostaglandin secretory pattern in pregnant alpacas suggests that PGF2 alpha peaks might occur at a frequency similar to that observed in nonpregnant animals but with a lower magnitude. PMID- 9360767 TI - Effect of prostaglandin F2 alpha treatment before norgestomet and estradiol valerate treatment on regression, formation, and function of corpora lutea in beef heifers. AB - Two experiments were conducted to determine if corpus luteum regression, formation, and function were associated with the decreased calving rate observed in beef females administered PGF2 alpha 5 days before Syncro-Mate B (SMB) treatment. Experiment 1 included 31 beef heifers 11 to 13 months old and experiment 2 included 31 beef heifers 19 to 21 months old. Heifers were randomly assigned to 1 of 2 groups (control and PGF2 alpha 5 days before SMB treatment). Heifers were bled 10 days before PGF2 alpha treatment, immediately before PGF2 alpha and SMB treatments, at the time of implant removal, and twice weekly after implant removal. Heifers in experiment 2 were observed twice daily for estrus for 5 days after PGF2 alpha treatment and for 3 days after norgestomet implant removal. Based on the blood samples collected before SMB treatment, 15 heifers in experiment 1 and every heifer in experiment 2 were with estrous cycles. All heifers in experiment 1 had progesterone concentrations < 0.5 ng/ml 2 days after implant removal. However, progesterone concentrations during the luteal phase in control heifers with estrous cycles were higher (P < 0.05) than in PGF2 alpha treated heifers with estrous cycles and in heifers previously without estrous cycles. In experiment 2, based on the occurrence of estrus and progesterone concentrations, heifers were also classified as metestrus or diestrus at the time of SMB treatment. The data were analyzed as a 2 x 2 factorial with treatment (control or PGF2 alpha) and stage of the cycle (metestrus and diestrus) as main effects. More metestrus heifers (40%) had progesterone concentrations > 1.0 ng/ml 2 days after implant removal than diestrus heifers (0%). In addition, progesterone concentrations during the luteal phase in metestrus heifers were lower (P < 0.05) than in diestrus heifers. PGF2 alpha treatment had no effect (P > 0.25) on the number of heifers with > 1.0 ng/ml progesterone 2 days after implant removal and progesterone concentrations during the luteal phase. There was no treatment by stage of the estrous cycle interactions. In summary, the administration of PGF2 alpha 5 days before SMB decreased the calving rate by causing more heifers to be metestrus at SMB treatment. Fewer metestrus heifers (than diestrus heifers) were synchronized (with < 1.0 ng/ml of progesterone 2 days after implant removal) to SMB treatment and those synchronized had lower progesterone concentrations during the luteal phase. PMID- 9360768 TI - Identifying infertile homozygous Inverdale (FecXI) ewe lambs on the basis of genotype differences in reproductive hormone concentrations. AB - Introduction of the Inverdale prolificacy gene (FecXI) could markedly improve reproductive efficiency in commercial flocks, but as homozygous carrier Inverdale ewes are infertile, it is imperative that these animals are identified at an early age and excluded from breeding stock. As the ovaries of homozygous carrier ewes are nonfunctional, there are wide differences in reproductive hormone levels between these and other Inverdale genotypes. This study assesses the accuracy of using hormone concentrations alone, to identify infertile homozygous ewe lambs. Ewe lambs were blood sampled at 2, 5 and/or 8 months of age, and plasma analyzed for follicle-stimulating hormone (FSH), luteinizing hormone (LH) and inhibin content. These animals were either the offspring of both known carrier rams and known carrier ewes, and therefore would be either homozygous (II) or heterozygous (I+) for the Inverdale gene (group 1, N = 122), or had one parent that was a carrier and therefore would be either heterozygous or noncarriers (++) of the gene (group 2, N = 32). Animals were designated as either II or I+/++ on the basis of their plasma hormone concentrations. Inverdale genotype was also assigned from laparoscopic observation of the ovaries at each of these occasions. Definitive assignment of genotype was made at laparoscopy as adults during the breeding season. On the basis of laparoscopy as adults, 62 (51%) lambs in group 1 were identified as homozygous and 60 (49%) as heterozygous. At all three ages, both mean FSH and mean LH concentrations were significantly higher in II than in I+ lambs. Mean inhibin concentrations were significantly lower in II lambs at 8 months, but did not differ significantly between genotypes at 2 or 5 month of age. The use of discriminant analysis techniques to segregate individual animals in group 1 on the basis of their plasma FSH and LH concentrations, correctly identified Inverdale genotype in 50/52 (96%) lambs at 2 months, 75/79 (95%) at 5 months and 118/122 (97%) at 8 months of age. Discriminant analysis was equally effective for segregating II ewe lambs (group 1) from fertile ewe lambs of I+ and ++ genotype (group 2, 97% correct at 5 months and 98% at 8 months). At no stage did inclusion of inhibin concentrations into the discriminant function alter the number of homozygous ewes misclassified. This demonstrates that infertile homozygous ewe lambs can accurately be distinguished from their fertile flockmates by using plasma concentrations of gonadotrophins alone, and that this can be achieved from as early as 2 months of age. PMID- 9360769 TI - The effect of prenatal photoperiodic history on the postnatal endocrine status of female lambs. AB - Postnatal photoperiodic experience plays a pivotal role in determining the timing of ovarian activity in female lambs. This study examines whether a photoperiodic history gained while in utero is able to influence this timing. Pregnant Soay ewes were maintained in either long days (n = 7, 18 h light: 6 h dark; group PLD) or short days (n = 12, 6 h light: 18 h dark; group PSD) from 25 days of gestation. At birth, female lambs (n = 8 per group) were transferred to long days for 10 weeks, and then placed under short days until the end of the experiment at 38 weeks of age. Blood samples were collected from lambs on the day of birth and three times weekly for the duration of the study and the resulting plasma assayed for progesterone and prolactin. Although both gestational photoperiods produced, at best, abbreviated periods of ovarian activity, lambs born to ewes which experienced long days during gestation (group PLD) exhibited elevated plasma progesterone concentrations significantly earlier (P < 0.05) than lambs born to ewes exposed to short days during gestation (group PSD) (mean +/- SEM, 193 +/- 17 versus 244 +/- 14 days for PLD and PSD groups, respectively. Plasma prolactin concentrations in newborn lambs born between late December and early April were not affected by the ambient photoperiod, but reflected the artificial daylength experienced by their mothers during gestation. Lambs born to ewes maintained under long days during gestation (group PLD) had significantly higher prolactin concentrations on the day of birth than lambs born to ewes maintained under short days during gestation (group PSD) (45 +/- 5.4 ng/ml versus 7 +/- 3.7 ng/ml respectively, P < 0.001). The mean birth weight, rate of live weight gain and live body weight of lambs at the end of the experiment did not vary significantly between treatment groups. These results suggest that the ovine foetus is sensitive to photoperiodic information prior to birth, and develops a photoperiodic history which, under the present experimental conditions, modulates the subsequent endocrine status of the neonatal lamb. PMID- 9360770 TI - Relationships among calving season, heat load, energy balance and postpartum ovulation of dairy cows in a subtropical environment. AB - The study was designed to examine the relationships among calving season, energy balance, temperature humidity index (THI), and postpartum ovulation in high producing cows in a subtropical environment. Holstein cows calving in a feedlot dairy in southeast Queensland during winter (n = 23) and summer (n = 21) were monitored during the first 9 weeks of lactation. Cows were weighed and blood samples collected twice weekly: plasma progesterone, plasma metabolites related to energy and mineral balance, and haematological measurements were performed. Milk production was measured, body condition score was estimated, and trans rectal ultrasound examinations of the ovaries were each undertaken once a week. The interval between calving and first ovulation was significantly longer in cows calving in summer (22.8 vs. 17.6 days, P < 0.05). Interval from calving to the first postpartum ovulation (FOVL) was inversely related to the mean plasma glucose concentration for the first 9 weeks after calving (GLU): FOVL = 80.0 17.9GLU, (R2 = 0.25, P < 0.001). Plasma progesterone concentration during the life of the second corpus luteum after calving was negatively correlated with THI during the first 2 weeks after calving (r = 0.55, P < 0.001). Plasma glucose concentration (GLU) was negatively correlated with milk yield (MYD) and rectal temperature (RT), and positively correlated with plasma calcium concentration (Ca) according to the following regression equation. GLU = 33.1 - 0.02MYD + 0.91Ca - 0.48RT, (R2 = 0.58, P = 0.0001). PMID- 9360771 TI - The distribution of ovulations from the ovaries of merino and Border Leicester x merino ewes and its effect on the survival of their embryos. AB - The distribution of ovulation between the right and the left ovary was recorded using endoscopy, in 2806 ewes over a 5-year period. Fifteen separate tests were conducted as part of the development programme for a commercial twinning vaccine. There were significantly more ovulations on the right ovary (53.4%) compared to the left ovary (46.6%; P < 0.001). The distribution of ovulation between the ovaries was not influenced by either the breed of sheep or prior immunisation against the steroid hormones androstenedione or testosterone. These findings suggest that the hormonal control of folliculogenesis and ovulation rate is modulated by unknown local factors within the ovary and its vasculature. The site of ovulation had no effect on embryo survival, and embryos from unilateral ovulations were just as likely to survive as were embryos from bilateral ovulations. However, embryo survival was influenced by ovulation rate, and ewes with ovulation rates of four or more had reduced litter sizes and lower embryo survival. PMID- 9360772 TI - The potential transmission of infectious agents by semen packaging during storage for artificial insemination. AB - Plastic straws, of a type widely used for semen cryopreservation, sealed using three different methods, (PVA powder, plastic spheres and plasticine modelling clay) were tested for leakage of low molecular weight dye (methylene blue), bacteria (Escherichia coli) and virus (Newcastle disease virus). Leakage was found to be dependent on the method used to fill the straws. Straws filled using a traditional 'dip and wipe' method and sealed with PVA powder demonstrated a significant degree of methylene blue leakage (0.0269% of the total straw contents) probably associated with contamination of the powder sealing plug. Straws filled using an aseptic filling technique showed no detectable leakage of any agent with any of the sealing methods. This study highlights the need to establish good-practice guidelines for the packaging of semen collected for freezing and future AI from non-domestic livestock where disease-free status cannot be guaranteed and unsophisticated technology is used. PMID- 9360773 TI - Selective attention to conjunctions of color and shape of alphanumeric versus non alphanumeric stimuli: a comparative electrophysiological study. AB - We compared multi-dimensional selection on the basis of the color, the global shape and the local shape of alphanumeric (letters) and non-alphanumeric (non letters) stimuli. We investigated whether letters are selected on the basis of name codes or on the basis of highly familiar local shape codes. Participants responded to a single conjunction of color, global shape and local shape occurring in a randomized stream of other conjunctions of these attributes. Dependent variables were reaction time and measures derived from event-related brain potentials (onset latencies and peak amplitudes of the occipital selection negativity, SN). The SN results showed that, for both letters and non-letters, color and global shape were selected first and local shape was selected later. Reaction times were faster, and SN to the local shape occurred earlier for letters than for non-letters. The SN to the local shape of letters was larger than the SN to the local shape of non-letters. In contrast, the SN to the global shape of letters was smaller than the SN to the global shape of non-letters. Selection of the global shape of letters, but not of non-letters, depended on whether they occurred in the relevant color. Selection of the color of both letters and non-letters was independent of shape relevance, and selection of the local shape of both letters and non-letters was independent of color relevance. These results suggest that, (1) both letter and non-letter shapes are initially analyzed in a feature-specific manner; and (2) letters are selected for task directed processing on the basis of highly familiar local shape codes and not on the basis of name codes. PMID- 9360774 TI - Conditioned inhibition of autonomic Pavlovian conditioning in humans. AB - The present study aimed to demonstrate conditioned inhibition of Pavlovian conditioning of autonomic responses in humans. Subjects (N = 21) were presented initially with four geometric shapes (A, B, C and D). An electric shock served as the unconditioned stimulus (US) during acquisition. Conditional stimuli lasted for 8 s and US onset coincided with CS offset. Subjects were trained with A-US, C US, and AC-US pairings and AB alone and B alone presentations. The subsequent summation test consisted of C-US pairings and CB alone and CD alone presentations. Conditioning was evident in self-reported US expectancy and first and second interval electrodermal responses. Evidence for conditioned inhibition during the summation test was found in US expectancy and second interval electrodermal responses. PMID- 9360775 TI - Emotional modulation of the startle reflex in twins: preliminary findings. AB - This study investigated twin similarity in general startle reflex reactivity and emotional modulation. Seventeen monozygotic (MZ) and 12 dizygotic (DZ) male twin pairs received startling acoustic stimuli while viewing emotionally positive, negative and neutral slides. Electromyographic (EMG) responses were recorded from the orbicularis oculi. Members of MZ twin pairs had similar response amplitudes under all three valence conditions. In addition, modulation scores for the positive and negative conditions, representing the percent change in response amplitude between the affective and the neutral conditions, also showed significant similarity within MZ twin pairs. Overall, members of DZ twin pairs were not found to be significantly similar of any of the measures. These preliminary findings suggest that emotional modulation of the startle reflex shows familial resemblance within MZ pairs. Given the lack of resemblance between DZ twins, it is tentatively suggested that affective modulation may be under partial genetic control. PMID- 9360776 TI - Evoked heart rate and blood pressure in an S1-S2 paradigm. AB - Phasic changes in heart rate (HR) and blood pressure (BP) in an S1-S2 paradigm were studied in three experiments. In each experiment, a memory search task was performed at S1. The outcome of this task indicated whether a fast or a delayed response had to be given after S2. Besides this response instruction, there were two other task manipulations: in one experiment the memory load at S1 was varied, whereas in each experiment a different kind of performance feedback was given. Both HR and BP showed a triphasic pattern, consisting of an initial decrease, followed by an increase and another decrease. The BP patterns were quite consistent, and delayed a few seconds relative to the HR pattern. The memory load manipulation at S1 showed that the changes early in the S1-S2 interval (initial decrease and subsequent increase) reflect the processing of S1. The effects of response instruction showed that the second HR deceleration, and the subsequent BP decrease, reflect the preparation of the motor response. In Experiment 2 the level of the evoked HR and BP pattern was shifted as a function of the type of reward (a bonus or noise). PMID- 9360777 TI - Snoring, nightmares, and morning headaches in elderly women: a preliminary study. AB - Self-reported snoring in 37 females aged 65-94 years was assessed and the relationships between snoring and sleep characteristics, respiratory events, depression scores, sleep complaints and self-reported health problems were investigated. Sleep was recorded for two 24-h periods in the home on successive weeks, using the Home Monitoring System. Snoring was positively correlated with the frequency of nightmares and morning headaches; and nightmares and morning headaches were significantly correlated. Snoring was also significantly and positively correlated with the number of brief wakings during sleep, and was positively correlated with weight. While these relationships are ones that have previously indicated risk status, snoring was not related to respiratory events, sleep complaints, or other health problems. Snoring, nightmares and headaches each showed a significant, negative correlation with age, but this is a finding that cannot be readily interpreted from a cross-sectional study. Replication of this study with a larger sample, studied longitudinally, is required to confirm a significance of the snoring/nightmares/headaches constellation for aging women. PMID- 9360778 TI - Self-renewal of stem cells. AB - The mechanisms that regulate the fate of hematopoietic stem cells are poorly understood. Hematopoietic growth factors and factors in the microenvironment are clearly essential for ensuring the survival and differentiation of hematopoietic stem cells, but their role in the selection between self-renewal and lineage commitment options is unclear. Differences in the functional behavior of purified stem cells at different stages of development suggest that developmentally regulated intrinsic factors may play an important role in directing stem cell fate. Recent studies strongly implicate homeobox genes in these processes and have further emphasized the link between developmental and stem cell biology. Changes in stem cell function during development correlate with measurable changes in telomere length, and loss of telomere repeats may limit the replicative potential of stem cells. In order to reconcile developmental changes in stem cell properties with loss of telomeric DNA, the intrinsic timetable model of stem cell biology is introduced. In this model, the self-renewal properties of stem cells are relative and their replicative potential is limited to less than 100 cell divisions. PMID- 9360779 TI - Ribozyme-mediated inhibition of a Philadelphia chromosome-positive acute lymphoblastic leukemia cell line expressing the p190 bcr-abl oncogene. AB - The bcr-abl oncogene is the molecular counterpart of the Philadelphia chromosome (Ph), which is detected in > 95% of patients with chronic myelogenous leukemia (CML) and 20-30% of adults with acute lymphoblastic leukemia (ALL). Leukemic cells from patients with CML express the p210 form of the bcr-abl oncogene, whereas in adult Ph+ ALL approximately 50% of cases express the p190 form of the bcr-abl oncogene, and the other 50% express the same p210 gene as is found in CML. In this study, we have designed hairpin ribozymes (RZs) specific for the p190 form of the bcr-abl oncogene to inhibit the growth of a p190 Ph+ ALL cell line, Sup-B15. The RZs cleave p190 RNA substrate in a cell-free in vitro assay. In the presence of the liposome, DMRIE-C, the RZs are protected from serum mediated catalysis in vitro. Anti-p190 RZs transfected with DMRIE-C as the vector into K562 cells, which express the p210 bcr-abl oncogene, are stable intracellularly for up to 96 hours. Up to 33% of the DMRIE-C and RZ mixtures are taken up by Sup-B15 cells cultured in suspension. Expression of the p190 bcr-abl protein product is specifically inhibited as demonstrated by Western blot analysis. Cell growth of the Sup-B15 cells is completely inhibited by anti-p190 RZs over four days in culture. Anti-p210 RZs have no significant effect on bcr abl protein expression or cell growth by Sup-B15 cells. RZs may have a role in purging stem cell populations collected from patients with Ph+ ALL in the context of autologous bone marrow transplantation. PMID- 9360780 TI - Peptide analogs that inhibit IgE-Fc epsilon RI alpha interactions ameliorate the development of lethal graft-versus-host disease. AB - Significant increases in serum levels of IgE have often been observed in allogeneic bone marrow transplantation patients and have generally been thought to be diagnostic of graft-versus-host disease (GVHD), rather than an agent involved in the pathogenesis of the disease. Experimental murine GVHD models have also indicated associations of hyper-IgE activity, yet the role of IgE in GVHD pathogenesis has never been tested directly. In the current study, we have tried to address this issue by using recently developed peptide analog antagonists for the interaction of IgE with the Fc epsilon RI receptor, which is necessary for triggering mast cells and other cell types when cross-linked by antigens. A synthetic cyclized 13-amino acid peptide was previously designed from the modeled C-C' loop region of the Fc epsilon RI alpha-chain and was found to act as a competitive inhibitor of IgE-Fc epsilon RI alpha binding. The peptide was generated in two forms, a cyclic L-(L-IgEtide) and retro D-amino acid composition (rDIgEtide), the latter to increase resistance to protease degradation for in vivo applications. These two inhibitor peptides were then used to test the hypothesis that IgE could be involved in the pathogenesis of acute GVHD, in the B10.D2-->DBA/2 (900 cGy) strain combination, with GVHD directed to minor histocompatibility antigens. Both peptides demonstrated significant inhibition of the development of lethal GVHD, supporting the involvement of IgE at some level of disease pathogenesis. PMID- 9360781 TI - Methotrexate and cyclosporine for graft-vs.-host disease prevention: what length of therapy with cyclosporine? AB - One hundred three patients with leukemia, aplastic anemia, or myelodysplastic syndrome were treated by marrow transplantation from genotypically HLA-identical siblings (n = 92) or HLA haploidentical family members differing for one HLA antigen on the nonshared haplotype (n = 11). To prevent graft-vs.-host disease (GVHD), they were administered postgrafting immunosuppression with a short course of intermittent methotrexate with daily cyclosporine for no more than 11 days. Customarily, we have given cyclosporine for 180 days after transplant. In the current study, we asked whether cyclosporine could be stopped earlier without affecting the risk of chronic GVHD. By day 60, patients who never had acute GVHD, or whose acute GVHD had resolved, were randomized to have cyclosporine stopped (n = 52) or continued for the usual 180 days (n = 51). Results were analyzed with a median follow-up of 9.3 years after transplant, and showed that patients in whom cyclosporine was discontinued on day 60 had a significantly more rapid onset (p = 0.001), but not a significantly higher overall incidence of chronic GVHD than those in whom the drug was stopped on day 180 (43 vs. 54%; p = 0.26). Transplant related mortality was comparable among patients without preceding acute GVHD, regardless of when cyclosporine was discontinued (11% for both study arms). However, transplant-related mortality appeared to increase among patients with preceding acute GVHD in whom cyclosporine was stopped by day 60 (38 vs. 17%). Results suggest that cyclosporine can safely be discontinued early in patients who never had evidence of acute GVHD, while those with preceding acute GVHD would benefit from a longer course of the drug. Because of the relatively small sample sizes, these results would best be treated as promising preliminary findings that should be confirmed in larger randomized studies. PMID- 9360782 TI - Peripheral neuropathy after bone marrow transplantation. AB - Peripheral neuropathy after bone marrow transplantation can produce motor disability with significant morbidity and mortality, particularly when the neuropathy occurs within the first few months of the transplant. Most of these severe neuropathies have demyelinating features on electrophysiologic tests and histopathology, characteristic of immunologically-mediated neuropathies. The specific immune mechanism is uncertain. It is possible that cyclosporin, FK-506, and interferon-alpha may all trigger immunologically mediated neuropathies in rare patients. Transplants in patients with pre-existing demyelinating neuropathy may result in abrupt exacerbation of the neuropathy. Other causes of severe neuropathies include high-dose cytosine arabinoside and critical illness polyneuropathy. Less severe neuropathies with primarily sensory deficits may result from etoposide conditioning, thalidomide treatment for graft-versus-host disease, and the chemotherapeutic agents cisplatin and paclitaxel when used at high-dose with peripheral stem cell support. When encountering patients with disabling motor neuropathies, transplant physicians must identify (with the aid of nerve conduction tests) those neuropathies that are likely to be immunologically mediated and then empirically add or alter immunosuppressant therapies. Unfortunately, experience has been too limited to suggest specific regimens or the optimal sequence of immunosuppressant therapies. PMID- 9360783 TI - A phase II multicenter trial of high-dose sequential chemotherapy and peripheral blood stem cell transplantation as initial therapy for patients with high-risk non-Hodgkin's lymphoma. AB - The purpose of this study was to evaluate the safety and feasibility of front line high-dose sequential (HDS) chemotherapy with peripheral blood stem cell (PBSC) transplantation in patients with newly diagnosed high-risk non-Hodgkin's lymphoma (NHL). Thirty-two patients with high-risk NHL (defined by the age adjusted international index) underwent HDS chemotherapy followed by PBSC transplantation and consolidative radiotherapy. Twenty-eight patients (88%) had intermediate/high grade NHL and four patients (12%) had small noncleaved or lymphoblastic lymphoma. Twenty-four patients were classified as high-intermediate risk (two risk factors) and eight patients were classified as high-risk (three risk factors). The five phases of HDS (see Fig. 1) consisted of Phase I (adriamycin, vincristine, and prednisone); Phase II (cyclophosphamide, filgrastim [G-CSF], and PBSC harvest); Phase III (methotrexate, leucovorin, vincristine; Phase IV (etoposide, filgrastim [G-CSF]); and Phase V (mitoxantrone, melphalan, autologous peripheral blood stem cell infusion, and filgrastim [G-CSF]). Radiation therapy was given to sites of previous bulk disease, 2400 cGy, (D + 30 100)]. Toxicity, engraftment, hospital utilization, overall survival, and relapse free survival were evaluated. The high-dose sequential chemotherapeutic regimen was well tolerated. Treatment-related mortality was 6.25% with two deaths occurring secondary to sepsis and one death was caused by progressive disease. The major toxicity in Phase I-IV was grade 3 nausea/vomiting. The major toxicity in Phase V was grade 3 or 4 nausea/vomiting and mucositis. The median follow-up is 18.8 months (range 4-44 months). The overall survival (OS) and relapse-free survival (RFS) at 18 months for all patients were 78% (95% CI 37-90%) and 67% (95% CI 46-88%), respectively. The OS at 18 months for all patients, excluding the four patients with either small noncleaved or lymphoblastic lymphoma, was 82% (95% CI 65-98%) vs. 30% (95% CI 0-86%) (p = 0.0059). One patient in this latter group remains alive at 6 months follow-up. The RFS for all patients, excluding the four patients with either small noncleaved or lymphoblastic lymphoma, was 78% (95% CI 58-97%) vs. 0% (95% CI 0-0%) (p = 0.0004). High-dose sequential chemotherapy with initial PBSC transplantation is well tolerated and appears effective in high-risk NHL. Superior results were noted in patients with intermediate grade versus those with small noncleaved or lymphoblastic NHL. PMID- 9360785 TI - Warning regarding the extra-label use of the fentanyl patch. PMID- 9360784 TI - Cytokine-primed bone marrow stem cells vs. peripheral blood stem cells for autologous transplantation: a randomized comparison of GM-CSF vs. G-CSF. AB - Autologous transplantation for non-Hodgkins lymphoma and Hodgkin's disease is widely used as standard therapy for those with high-risk or relapsed tumor. Peripheral blood stem cell (PBSC) collections have nearly completely replaced bone marrow stem cell (BMSC) harvests because of the perceived advantages of more rapid engraftment, less tumor contamination in the inoculum, and better survival after therapy. The advantage of PBSC, however, may derive from the hematopoietic stimulating cytokines used for PBSC mobilization. Therefore, we tested a randomized comparison of GM-CSF vs. G-CSF used to prime either BMSC or PBSC before collection for use in autologous transplantation. Sixty-two patients receiving transplants (31 PBSC; 31 BMSC) for non-Hodgkin's lymphoma (n = 51) or Hodgkin's disease (n = 11) were treated. All patients received 6 days of randomly assigned cytokine. Those with cellular marrow in morphologic remission underwent BMSC harvest, while those with hypocellular marrow or microscopic marrow tumor involvement had PBSC collected. Neutrophil recovery was similarly rapid in all groups (median 14 days; range 10-23 days), though two patients had delayed neutrophil recovery using GM-CSF primed PBSC (p = 0.01). Red cell and platelet recovery were significantly quicker after BMSC mobilized with GM-CSF or PBSC mobilized with G-CSF. This speedier hematologic recovery resulted in earlier hospital discharge as well. However, in multivariate analysis, neither the stem cell source nor randomly assigned G-CSF vs. GM-CSF was independently associated with earlier multilineage hematologic recovery or shorter hospital stay. Relapse free survival was not independently affected by either the assigned stem cell source or the randomly assigned priming cytokine, though malignant relapse was more frequent in those assigned to PBSC (RR of relapse 3.15, p = 0.03). These data document that BMSC, when collected following cytokine priming, can yield a similarly rapid hematologic recovery and short hospital stay compared with cytokine-primed PBSC. Using primed BMSC, no difference in malignant relapse or relapse-free survival was observed. These findings suggest that despite widespread use of PBSC for transplantation, BMSC, when collected following hematopoietically stimulating cytokines, may remain a satisfactory source of stem cells for autologous transplantation. G-CSF and GM-CSF are both effective in priming autologous PBSC or BMSC for collection. PMID- 9360786 TI - Another viewpoint on the use of a tranquilizer gun by a shepherd. PMID- 9360787 TI - An ethicist's commentary on the mismanaged cesarean section. PMID- 9360788 TI - Monitoring government regulations. PMID- 9360789 TI - Giardia and Cryptosporidium in dairy calves in British Columbia. AB - A study was undertaken to determine the prevalence of Giardia infections in dairy calves and to compare Giardia and Cryptosporidium infections in calves of different ages. Fresh fecal samples were collected from 386 male and female Holstein calves (newborn to 24 wk) in 20 dairies located in the lower Fraser river valley area of British Columbia. Giardia intestinalis, Cryptosporidium parvum, and Cryptosporidium muris were enumerated in each sample after concentration by sucrose gradient centrifugation and immunofluorescent staining. Giardia was identified at all farm locations. The overall prevalence of Giardia in calves was 73% with a geometric mean cyst count of 1180 cysts per gram of feces (CI, 41 to 5014). Cryptosporidium parvum and C. muris were identified in 80% and 40% of the farms, respectively. The prevalence of C. parvum was 59%, and the geometric mean for oocysts was 457 oocysts per gram of feces (CI, 18 to 160). The prevalence of C. muris was only 2% and the mean oocyst counts were 54 oocysts per gram of feces. Giardiasis was not age dependent, and approximately 80% of the calves from 2 to 24 wk were infected. In contrast, C. parvum infections were predominant in calves 2 to 4 wk, while C. muris was demonstrated in calves older than 4 wk. Fourty-seven percent of calves with diarrhea had high numbers of Giardia cysts in their feces. Giardia infections are highly prevalent in dairy calves and should be considered in animals with diarrhea or failure to thrive. PMID- 9360790 TI - A comparison of certified and noncertified pet foods. AB - The market presents the buyer with a wide array of pet food choices. Marketing pet foods has changed in the last decade and today foods may be bought at a variety of outlets. The present study compares nutrient composition, digestibility, and effect on urine pH (cat foods only) of selected certified and noncertified pet foods from different outlets. The selected foods were considered analogous in terms of declared ingredients and macronutrient profiles. The analytical methods used were those of the Association of Official Analytical Chemists as described in the Pet Food Certification Protocol of the Canadian Veterinary Medical Association. The test foods were sampled 4 times from August 1994 to July 1995. Both certified and noncertified products met the nutritional requirements on a consistent basis, although 1 of the noncertified dog foods consistently failed to meet the zinc requirements. This same product also failed to meet the Canadian Veterinary Medical Association's standards for concentrations of protein, calcium, and phosphorus. One of the noncertified cat foods failed to meet the recommended calcium level. With the exception of fat digestion in 1 noncertified food, there were no statistically significant differences in major nutrient digestibility between certified and noncertified pet foods. There were some statistically significant differences in digestibility within both the certified and noncertified groups of foods. The practical significance of any of the statistical differences in digestibility is uncertain. Urine pH observed in cats fed noncertified test diets was variable, with some values greater than 7.0 as a maximum or 6.5 as an average. The general conclusion of this study was that the commonly available certified products were the nutritional equal of those foods that position themselves as "premium." PMID- 9360791 TI - Use of test day milk fat and milk protein to detect subclinical ketosis in dairy cattle in Ontario. AB - Serum beta-hydroxybutyrate (BHB) levels were determined for 1333 dairy cows in various stages of lactation and parity on 93 dairy farms in Ontario. The data were collected in a cross-sectional manner, as part of the 1992 Ontario Dairy Monitoring and Analysis Program. The median serum BHB was 536 mumol/L for all cows, with a range of 0 to 5801 mumol/L. When subclinical ketosis was defined as a serum BHB level of 1200 mumol/L or higher, the prevalence of ketosis for cows in early lactation (< 65 days in milk (DIM)) was 14.1%. Prevalences for mid lactation (65-149 DIM), late lactation (> 149 DIM), and dry cows were 5.3%, 3.2%, and 1.6%, respectively. The mean serum BHB was significantly higher in the early group compared with each of the other 3 groups (P < 0.05). There was a trend of increasing prevalence with increasing parity across all stages of lactation. Only the difference between the parity-1 group and the parity-4 and greater group was statistically significant (P < 0.05). Both test-day fat percent and test-day protein percent were significantly associated with subclinical ketosis. However, test-day fat percent and test-day protein percent, used alone or in combination, were not useful screening tests for identifying cows with subclinical ketosis. PMID- 9360792 TI - Hypereosinophilia in a horse with intestinal lymphosarcoma. AB - Paraneoplastic eosinophilia is reported in dogs, cats, and humans. Hypereosinophilia (an eosinophil count greater than 1.5 x 10(9) L) is often associated with metastasis and a poor prognosis. This report describes a case of paraneoplastic hypereosinophilia in a pony. Neoplasia should be included in the differential diagnoses in a horse with eosinophilia. PMID- 9360793 TI - Lead toxicosis in 2 dwarf rabbits. PMID- 9360794 TI - British Columbia. Canine Cryptococcus neoformans. PMID- 9360795 TI - Double standards. PMID- 9360796 TI - Diagnostic ophthalmology. PMID- 9360797 TI - Diagnosis & management of acute & chronic sinusitis. PMID- 9360798 TI - Medical management of Bell's palsy. PMID- 9360799 TI - Evaluation of the dizzy patient. AB - This discussion has focused primarily on the history and physical examination of the patient with dizziness which, in fact, are the two most important elements in the evaluation process. To perform the examination expeditiously and completely, a broad differential diagnosis of dizziness must be kept in mind. The clinician should also keep in mind two basic objectives: first, to identify serious pathology (e.g., central nervous system lesion, brainstem ischemia, cardiac arrhythmia); and second, to recognize diseases that can be specifically treated, such as an endocrine abnormality, middle ear infection, Meniere's disease, or a drug reaction. Reassurance and/or vestibular rehabilitation are the mainstays of therapy for the patients not falling into the above two categories. PMID- 9360800 TI - Diagnosis & management of cutaneous malignancies of the head & neck. PMID- 9360801 TI - Blunt trauma to the face & neck: initial management. PMID- 9360802 TI - The patient with a neck mass. PMID- 9360803 TI - Evaluation of sensorineural hearing loss. AB - Advances in both the medical/surgical and nonmedical treatment of sensorineural hearing loss have drastically increased the need for more precise evaluation of inner ear disorders and their differentiation from retrocochlear sites of lesion. Consider, for example, the tremendous strides made in the application of cochlear implants to patients with severe to profound hearing loss who are unable to derive sufficient or adequate benefit from hearing aids. Equally impressive are the improvements made recently in the area of assistive listening technology. The newest hearing aid devices are smaller in addition to being capable of greater fidelity, and contain digital circuitry making them more flexible and responsive to a patient's auditory needs. A challenge for hearing healthcare professionals today is to successfully address the needs of the millions of hearing impaired individuals in the United States who are currently not adequately served, either medically or nonmedically, for their hearing problem. PMID- 9360804 TI - The vestibular & balance center: tools for diagnosing the dizzy patient. AB - Without access to adequate diagnostic facilities, management of vestibular and balance disorders can be a frustrating process for both clinicians and patients. Expert clinical staff and state-of-the-art tools for the evaluation of balance disorders and dizziness are available within the vestibular and balance center. These centers can provide referring physicians and their patients with access to diagnostic expertise and facilities not practical within a general practice environment. Providing detailed evaluative reports, balance centers can help the referring physician define directions for surgical and medical treatment and assist in the management and rehabilitative treatment of acute and chronic dizziness and balance dysfunction. PMID- 9360805 TI - Selecting the best employees. PMID- 9360806 TI - Mibefradil (posicor). PMID- 9360807 TI - Urinary incontinence in the elderly: a growing problem that needs attention. AB - An increasing proportion of the population is reaching old age and, as a result, conditions such as incontinence that were often not discussed publicly in the past are receiving broader attention. The prevalence of incontinence increases with age and with declining health. Elderly women with incontinence require careful evaluation and management because of their associated medical problems, decline in cognitive function, and limitations of resources. Both conservative and surgical treatments can be very successful, even in the very elderly. PMID- 9360808 TI - Morbidity of osteoporosis--can estrogen use make a public health impact? AB - The personal morbidity and economic burden associated with osteoporosis is substantial. Estrogen has been shown to have positive effects on the prevention and treatment of this disabling disease. Information is available with regard to when to initiate estrogen therapy, how long to maintain treatment, and how best to identify those women who will benefit most from its use. PMID- 9360809 TI - Alzheimer's disease: an estrogen link? AB - The prospect that Alzheimer's disease is caused by or related to estrogen deficiency, and treatable or even preventable by estrogen replacement therapy, is alluring. At present, evidence that Alzheimer's disease is an estrogen deficiency disease is lacking. However, there is much evidence that beneficial effects of estrogen replacement therapy on the areas of the brain associated with Alzheimer's disease may prevent or slow the progress of Alzheimer's disease or the expression of Alzheimer's disease symptoms. Given the proven value of estrogen replacement therapy for most women for other indications, this probable additional benefit is welcome. Further research is needed. PMID- 9360810 TI - Operating on the elderly woman--what are her special needs? AB - Current studies verify the safety of surgery in the elderly. Delirium is a costly complication, but its incidence and severity can be reduced by pre- and postoperative interventions. Avoidance of even mild hypothermia has now been shown to reduce cardiovascular morbidity. New information available on the cardiovascular response of elderly patients to laparoscopic surgery highlights the importance of avoiding preoperative dehydration. Proper pain management minimizes complications and promotes recovery. PMID- 9360811 TI - Urogynecology. PMID- 9360812 TI - Terminology of pelvic organ prolapse. AB - Pelvic organ prolapse is a common gynecologic condition, yet until recently no standard classification system to describe prolapse existed. A validated and standardized terminology system is now in use that allows accurate description of physical findings as well as meaningful communication between clinicians and comparisons of published series. PMID- 9360813 TI - Ultrasonography of the lower urinary tract. AB - Ultrasound evaluation in urogynaecology has evolved. Comparison with the old standard, lateral chain urethrocystography, as well as basic investigations of the sonographic technique and standardizations have created a basis for a new imaging standard and for further developments in urogynaecology. The recent progress indicates that sonography holds the key to the future of imaging in urogynaecology. PMID- 9360814 TI - Magnetic resonance imaging of the lower urinary tract. AB - Magnetic resonance imaging with its excellent contrast resolution and direct multiplanar imaging capacity, has become a valuable tool to improve understanding of lower urinary tract function and pelvic floor physiology. Review of the current English language literature shows that the domain of magnetic resonance imaging is research. In comparison with other imaging techniques, magnetic resonance imaging has been shown to yield better soft tissue differentiation and anatomic resolution. Newer techniques also allow some form of dynamic imaging. PMID- 9360815 TI - Anal incontinence after childbirth. AB - Advances in new imaging techniques have improved our understanding of the pathogenesis of anal incontinence after childbirth. Recent studies have confirmed the high prevalence of anorectal trauma and symptoms, although women rarely volunteer these symptoms. The way forward is to identify obstetric factors associated with anal incontinence and modify current practice to minimize morbidity. PMID- 9360816 TI - Preventive vaginal and intra-urethral devices in the treatment of female urinary stress incontinence. AB - A number of vaginal and urethral devices have recently been introduced for the treatment of female urinary stress incontinence. Nine recent studies of these were scrutinized. The median corrected subjective cured/improved rate was 63% for the vaginal and 43% for the urethral devices. The latter group have a high percentage of side-effects with related drop-outs. Urinary tract infection and migration of the device into the bladder are particularly worrying. The vaginal devices currently available compete favourably with other non-surgical forms of therapy for stress incontinence in terms of efficacy and safety. PMID- 9360817 TI - Effects of vaginal surgery on the lower urinary tract. AB - Vaginal surgery performed for pelvic floor relaxation, genuine stress incontinence or both can have intended and unintended effects on the lower urinary tract. Intended effects are restoration of anatomy and urinary continence; unintended effects include operative injury, recurrent prolapse, persistent or unmasked stress incontinence, and voiding difficulties. Objective long-term follow-up and new investigational techniques have led to a critical reexamination of standard and time-honoured vaginal operations, particularly anterior colporrhaphy. This review addresses the effects of different vaginal operations on the lower urinary tract and conduction studies of the perineal nerve. PMID- 9360819 TI - Marfan syndrome in pregnancy. PMID- 9360818 TI - Interstitial cystitis. AB - Interstitial cystitis is a urologic disorder with protean pelvic manifestations (urologic, gynecologic, gastroenterologic) and variable prevalence. Although current research indicates a non-bacteriologic etiology, interstitial cystitis has features suggestive of autoimmunity, a deficient bladder wall lining, activated bladder sensory neuropeptides and bladder mastocytosis. Pentosan polysulfate sodium is a recently approved oral treatment for interstitial cystitis. Further research into the gynecologic and pain aspects of interstitial cystitis is clearly needed. PMID- 9360820 TI - Adult and pediatric gynecology. PMID- 9360821 TI - Urogynecology. PMID- 9360822 TI - Current concepts in laceration repair. AB - Lacerations account for a significant number of emergency department and urgent care clinic visits for pediatric patients. Children represent a unique challenge in repairing lacerations because of their developmental and behavioral characteristics, making rapidity, ease of performance, and minimal pain particularly desirable. This review focuses on three concepts in laceration repair where there have been significant advances in the past several years in terms of new techniques and drugs. New pharmacologic modalities such as the fentanyl oralet for sedation of children are discussed as well as important nonpharmacological techniques such as parental presence. Topical administration of anesthetics such as tetracaine, adrenaline, and cocaine and lidocaine, epinephrine, and tetracaine offers the advantage of replacing lidocaine infiltration and provides an effective, safe, and painless alternative for local anesthesia. Finally, the introduction of cyanoacrylate tissues adhesives such as Histoacryl Blue (Trihawk International, Montreal, Canada) and Dermabond (Ethicon, Somerville, NJ) appear to be an ideal technique for laceration closure in children because they are easy and rapid to apply, are relatively painless, eliminate the need for suture removal, and provide an acceptable cosmetic result. PMID- 9360823 TI - Emergency Medical Treatment and Active Labor Act: legal concerns about private or managed care patients in the emergency department. AB - The Emergency Medical Treatment and Active Labor Act (EMTALA) was passed to prevent hospitals from refusing to care for an indigent patient in an emergency situation or transferring the patient before the emergency medical condition was stabilized. The act applies to all patients, whether or not they have insurance or belong to a managed care organization. At times, managed care organizations conflict with emergency departments on the treatment of children who present for care when life-threatening emergencies are not apparent. These conflicts frequently involve EMTALA with regards to medical screening examinations and transfer of patients from the emergency department to other facilities. PMID- 9360824 TI - Smoking and nicotine addiction: a pediatric epidemic with sequelae in adulthood. AB - Pediatric addiction to nicotine from cigarette smoking is a major public health problem, extracting a tremendous societal toll in terms of human suffering, a loss of future productivity, and the consumption of scarce health care resources. Teenagers smoke 1.1 billion packs of cigarettes yearly and will account for more than $200 billion in future health care costs. Recent behavioral studies confirm nicotine's ability to induce in adolescents both the tolerance and abstinence phenomena typical of other addicting substances. A range of adverse health effects, first detectable in adolescent cigarette smokers, extend into adulthood. Through the effects of environmental smoke or smoking during pregnancy, adolescent smokers affect not only their own health, but that of friends, family members, and even their own fetuses and children. Additional research into effective prevention and smoking cessation programs is urgently needed to forestall the ravaging of yet another generation by this preventable and deadly habit. PMID- 9360825 TI - Management of rabies exposure in pediatric practice. AB - The incidence of human rabies in the United States has fallen dramatically over the past 4 decades. This is directly related to the universal immunization of domestic cats and dogs. Recently, a number of cases of human rabies have been associated with the appearance of a previously rare strain of the virus in the silver-haired bat. There have been other recent changes in the epizoology of rabies with the expansion of raccoon rabies from a small pocket around northern Virginia to most of the northeastern United States. Postexposure prophylaxis using rabies immune globulin and rabies vaccine is effective in preventing rabies following a bite by a rabid animal when given according to current recommendations. There has been considerable debate, however, surrounding the cost of prophylaxis and the possibility of reducing the recommended number of doses of rabies immune globulin. PMID- 9360826 TI - Research in private pediatric practice and the challenge of network research. AB - Although most children receive their primary care in private physicians' offices, surprisingly little of the child health knowledge base has been generated from office settings. Research in practice settings is increasing, however, especially through networks of office-based pediatricians who are now collaborating with academic researchers to produce high-quality research on primary pediatric care. This paper provides a current overview of practice-based research in pediatrics, highlights contributions by regional and national pediatric research networks, and suggests directions for practice-based research in the future. PMID- 9360827 TI - Celiac disease: new thoughts on an old problem. PMID- 9360828 TI - Advances in the diagnosis and treatment of gastroesophageal reflux disease. AB - Pathophysiology and treatment of gastroesophageal reflux (GER) in children have often been extrapolated from studies in adult patients. Fortunately, many groups are now addressing GER specifically in relation to children. Abnormalities in gastrointestinal motility are described in gastroesophageal reflux GER, and there are several new studies looking at this issue in infantile GER. An international working group has put together recommendations for management of infantile GER. The results of a large pediatric study using omeprazole and a review of the use of the prokinetic cisapride in pediatrics are summarized. Several papers review recent experiences with laparoscopic fundoplication. New diagnostic modalities used to investigate GER in infants and children are discussed. These studies aid in both our understanding of possible pathogenesis of GER as well as treatment of the young patient with GER. PMID- 9360829 TI - An update on diseases of the pancreas in children. AB - The aim of this review is to describe recent developments in the field of pancreatic disorders in children. First, recent developments in the genetic research of hereditary pancreatitis are discussed. Subsequently, several issues of acute pancreatitis are presented. These include a description of the potential hazardous morbidity and mortality of this disorder in children. In addition, various novel etiologies that have been described lately in the medical literature are illustrated. Next, this paper discusses two examples of pancreatic disorders associated with systemic manifestations, i.e., ganglioneuromatosis and diabetes mellitus. Finally, a few rare genetic syndromes with pancreatic involvement are touched upon, an association that is not very well recognized. Cystic fibrosis is not covered. PMID- 9360830 TI - Treatment of acute diarrhea in children. AB - In the past decade a number of studies have systematically addressed the questions that existed regarding optimal ways to rehydrate and then refeed infants and children with diarrhea. Two very thorough papers are the highlights of the past year's publications in the topic of acute gastroenteritis in children. One summarizes the recommendations of the American Academy of Pediatrics and the other questions, with a background of past research and experience, the need to estimate fluid deficit in order to determine the fluid needs of each individual patient. Oral rehydration seems to be here to stay. Abundant literature supports its advantages over intravenous therapy in otherwise healthy children. Early refeeding also seems to be widely accepted, without a need for bowel rest, formula dilution, or systematic elimination of lactose. Age appropriate staple foods are also indicated along the refeeding process. PMID- 9360831 TI - Nutritional assessment in children and adolescents. AB - Accurate nutritional assessment of a child is a complex task involving simultaneous evaluation of several parameters, e.g., nutrient intake and requirement and physical and anthropometric examination, including body composition and biochemical markers. Several of these tests are not readily available in all settings and one may have to rely on simpler tools like thorough clinical assessment, which has a surprisingly high degree of sensitivity. PMID- 9360832 TI - Hepatitis C virus in infants and children. AB - Hepatitis C virus (HCV) affects approximately 1% of the world's people. In the past there has been a lack of interest in HCV in the pediatric population; however, new data are accumulating at an exponential pace about the epidemiology, clinical spectrum, HCV genotypes, and molecular variants and evolution of HCV infection in infants and children. Thousands of children with chronic hepatitis C are enrolled in multicenter and multinational clinical protocols and therapeutic trials. This paper highlights recent advances in diagnosis, epidemiology, natural history, and therapy for hepatitis C in children and the implications of these advances for pediatric and primary care practice. PMID- 9360833 TI - An 11-year-old boy with abdominal distension. PMID- 9360834 TI - Prevention of bacterial endocarditis. AB - A major review of the American Heart Association guidelines for endocarditis prophylaxis was published in 1997. In view of changing perspectives on the population at risk for endocarditis and new information on the likelihood of particular procedures to place patients at risk, simplified guidelines have been developed. The role of invasive procedures as a risk factor is deemphasized, simplified single-dose strategies are suggested, and parenteral regimens are required less frequently. In addition, more extensive alternatives to erythromycin, including the newer macrolide antibiotics, are now part of the recommendations for patients who are unable to take penicillins. The new report also discusses the appropriateness of prophylaxis in the presence of the complicated issue of mitral valve prolapse and the relationship of valvar flow patterns to risk for endocarditis. Although no definitive randomized trials have been performed unequivocally establishing the benefits of endocarditis prophylaxis, the new guidelines represent an effort to favorably modify the risk benefit ratio for use of antibiotics in the patient at risk. In addition to the new guidelines, other recent reports emphasize the importance of associated nonpharmacologic methods to prevent endocarditis, such as meticulous skin care and personal hygiene, and the need for a determined educational approach in the patient at risk to minimize risk. Recent reports have also emphasized the need for pediatric awareness of the changing patient population at risk for endocarditis and the need for increased vigilance in particular patients. PMID- 9360835 TI - Kawasaki disease. AB - Incidence of Kawasaki disease in Japan is 10 times higher than in the United States. Approximately 10% of patients have atypical clinical presentations. Because echocardiographic or angiographic evidence of coronary artery complications is needed for diagnosis, such atypical cases often result in either delay or omission of intravenous gamma globulin therapy and higher incidence of coronary artery aneurysms than those patients with classical presentations. Despite ongoing research, no universally accepted etiologic theory exists today. Intravenous gamma globulin remains the mainstay of the acute phase treatment of Kawasaki disease. However, reported transmission of hepatitis C virus via a brand of intravenous gamm globulin leaves us with a lingering concern about the safety of this treatment. In terms of long-term follow-up, emergencence of a number of newer diagnostic modalities is promising and warrants careful evaluation. Surgical therapy for coronary artery disease needs to be approached cautiously. PMID- 9360836 TI - Update on prospects for fetal cardiovascular surgery. AB - With progress in the field of fetal echocardiography, it has become clear that certain obstructive lesions of the heart and great vessels may progress in utero, leading to more severe disease. Prenatal intervention may mitigate this process, ultimately leading to improved outcomes for patients with certain severe congenital cardiac defects. In this review, we provide an update on the prospects for fetal cardiac intervention, with a focus on the field of fetal cardiac surgery. PMID- 9360837 TI - Atopic disease, rhinitis and conjunctivitis, and upper respiratory infections. AB - This review highlights recent information on the topics of atopic diseases and upper respiratory infections. Recent findings on the costs and therapies of atopic dermatitis are discussed. New insights into egg allergy, peanut allergy, food-induced exercise anaphylaxis, and the management of food allergy are presented. Topics highlighted in the section on asthma include airway remodeling and anti-inflammatory therapy, leukotriene synthesis inhibitors and receptor antagonists, steroid resistance and alternative therapy, and new delivery systems. Recent publications in the areas of allergic rhinoconjunctivitis and upper respiratory infections are also reviewed. PMID- 9360838 TI - Clonal origin of multiple lung cancers: K-ras and p53 mutations determined by nonradioisotopic single-strand conformation polymorphism analysis. AB - Disease stage is the most important factor in determining prognosis and treatment of lung cancer. Staging of lung cancer is complicated by presentation of multiple pulmonary malignant lesions with a similar histology. It is a dilemma to decide if these lesions are synchronous primaries arising from different malignant clones or metastases from a single clone. Lung cancer is associated with multiple genetic abnormalities including mutations of K-ras and p53, which are believed to occur prior to onset of metastasis. To determine the clonal origin of multiple pulmonary malginant nodules, we analyzed point-mutations of K-ras and p53 by microdissection, polymerase chain reactions (PCR), nonradioisotopic single-strand conformation polymorphism (SSCP) analysis, and DNA sequencing. Each pulmonary lesion was microdissected from paraffin slides. Genomic DNA was amplified by two sequential PCRs followed by electrophoresis in a minigel and silver staining. Deoxyribonucleic acid sequencing was performed if necessary to confirm a mutation found upon SSCP analysis. Applying this molecular approach, we were able to differentiate the clonal origins of multiple malignant nodules of the lung as exemplified by the two cases presented. PMID- 9360839 TI - Enriched SSCP: a highly sensitive method for the detection of unknown mutations. Application to the molecular diagnosis of lung cancer in sputum samples. AB - Detection of gene mutations by sensitive polymerase chain reaction (PCR)-based methods can allow to identify occult neoplastic cells in a great excess of nonmalignant cells. These molecular approaches have an enormous potential in terms of early diagnosis, detection of occult micrometastases of solid tumors, and minimal residual disease in patients with hematopoietic malignancies. Currently, the applications of such methods are limited, mainly because the high sensitivity required for the identification of rare mutated alleles can be achieved only in cases in which mutations occur in few specific codons of a gene or when the mutation is already known. No methods are available by which few alleles with unknown mutations in tumor genes can be recognized in a great excess of wild-type alleles. We have developed an extremely sensitive method, termed enriched single-strand conformational polymorphism (E-SSCP), which permits detection of a rare alleles with unknown mutations. The method is based on the observation that after a conventional SSCP analysis the vast majority of mutated bands migrate close to the wild-type bands. The area of the gel having the highest chance to hold mutated alleles is physically isolated and is used as substrate for a second round of SSCP. Serially diluted DNA samples containing gene mutations demonstrated detection of 1 mutant/10(6) normal alleles. The E SSCP assay was first applied to six sputum samples of patients affected by lung cancers with known p53 mutations showing in sputa the same mutations observed in tumors. The technique was then applied to eight cytologically negative sputum samples obtained from patients who later developed a clinically manifested lung carcinoma. In three cases, harboring a p53 mutation in tumor tissue, the E-SSCP analysis allowed the detection of the mutations in sputa months before clinical diagnosis. In conclusion, we have presented a general, highly sensitive technique for the detection of unknown mutations that may have several potential applications and may hold considerable promise for the early detection and study of cancer. PMID- 9360840 TI - Telomerase activity in human benign prostate tissue and prostatic adenocarcinomas. AB - Telomerase adds a hexanucleotide telomeric sequence to the chromosomal ends during replication and is postulated to play a role in cellular senescence and immortalization. Thirty-four human prostate tissues (18 malignant; 16 benign) were analyzed for telomerase activity by a sensitive nonradioactive polymerase chain reaction (PCR)-based method using the TRAP-eze telomerase detection kit (Oncor, Inc., Gaithersburg, MD). Telomerase activity in the homogenized tissue extracts was correlated with tumor grade, pathologic stage, and DNA ploidy. Specimens that exhibited the 36 bp internal control band and a ladder of products with 6-base increments starting with 50 nucleotides were considered positive. Fourteen (78%) of 18 prostatic adenocarcinomas (PACs) and only 2 (13%) of 16 benign prostate tissues exhibited telomerase activity. Our results indicate that, in contrast to most benign prostate tissues, telomerase activity can be detected in the majority of PACs and appears to be independent of tumor grade, stage, or DNA ploidy. Telomerase expression is occasionally detected in benign prostatic tissues bordering PACs and may result from either the presence of undetected tumor foci in these stored specimens or the proliferative response of the benign elements to adjacent cancer. PMID- 9360841 TI - Bcl-2 expression and DNA fragmentation in breast carcinoma, pathologic and steroid hormone receptors correlates. AB - B-cell leukemia/lymphoma (bcl-2) expression can override the apoptosis development in lymphoid and hormonally regulated tissue-like breast. The presence of estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR) have revealed in breast carcinomas, but they have not been correlated to the bcl 2 protein expression and DNA fragmentation markers. We evaluated the immunohistochemical expression of bcl-2 protein and hormonal receptors (ER, PR, AR) and differentiation grade in 37 infiltrating ductal carcinomas of the breast for which frozen tissues were available for DNA extraction. The immunohistochemical reaction for bcl-2 was considered positive if more than 50% of neoplastic cells had intense cytoplasmic staining, whereas for steroid receptor evaluation Battifora's criteria were used. The DNA was extracted according to the phenol-chloroform procedure and used for bcl-2 gene rearrangement study of the major breakpoint region (Southern blot) and for membrane-based end-labeling using digoxigenin-labeled nucleotides and E. coli DNA polymerase I (Klenow fragment). The results were quantified by three different observers. Low-grade carcinomas were positive for bcl-2 protein (27/28, 96.4%) and ER (15/28, 53.6%), whereas the remaining neoplasms were negative for bcl-2 (9/9, 100.0%) and ER (8/9, 53.6%) (p < 0.001). No statistically significant differences were revealed at the bcl-2, PR and AR comparisons. The Southern blot analysis for bcl-2 major breakpoint region showed neither rearrangement nor genetic amplification (densitometric study). Only the membrane-based end-labeling of DNA fragments showed correlation with bcl-2 protein and ER expressions: all except one bcl-2-negative tumor and two bcl-2-positive tumors had positive labeling using 7 pg of DNA at dot blot analysis (p < 0.002). The bcl-2 protein expression would allow both proliferation and cell progression by blocking apoptosis in well-differentiated, ER-positive breast carcinomas. In these neoplasms, DNA fragmentation as a molecular marker of apoptosis was prevented by bcl-2 expression. PMID- 9360842 TI - Loss of expression of a 55 kDa nuclear protein (nmt55) in estrogen receptor negative human breast cancer. AB - We have identified and characterized a 55 kDa nuclear protein (referred to as nmt55) from human breast tumors and MCF-7, human adenocarcinoma breast cell line, using site-directed monoclonal antibodies. Measurements of estrogen receptors (ER) and progesterone receptors (PR), by ligand binding assays, in cytosols of 63 human breast tumors permitted classifications of these tumors into four phenotypes (ER+/PR+, ER+/ PR-, ER-/PR-, ER-/PR+). Nuclear protein (nmt55) expression in these tumors, as determined from Western blot analyses, showed a statistically significant association (p = 0.001) with tumor hormonal phenotype. Review of the pathologic characteristics of tumors analyzed suggested that lack of nmt55 expression was significantly associated with mean tumor size (p < 0.03), mean ER (p = 0.001) and mean PR (p < 0.002), but was not associated with tumor stage, grade, or type. To further study this protein, we cloned and sequenced a 2.5 kb cDNA using a monoclonal antibody to nmt55. The complete predicted open reading frame encodes a protein with 471 amino acids and a calculated molecular mass of 54,169 Da. The deduced amino acid sequence exhibited unique regions rich in glutamine, histidine, arginine, and glutamic acid. Northern blot analysis of RNA from MCF-7 cells and ER+/PR+ human breast tumors showed a 2.6 kb mRNA. Southern blot analysis suggested the presence of a single copy of this gene. Chromosomal mapping, using fluorescent in situ hybridization (FISH), located nmt55 gene to the X chromosome, region q13. The extensive homology between nmt55 and RNA binding proteins suggested that nmt55 may be involved in hnRNA splicing. The strong association observed between expression of nmt55, tumor hormonal phenotype, mean tumor size, mean ER, and mean PR content suggests that loss of nmt55 expression may be related to events involved in hormone insensitivity, tumor differentiation, and unregulated tumor cell growth and metastases. PMID- 9360843 TI - The pattern of p53 and p21WAF1/CIP1 immunoreactivity in non-Hodgkin's lymphomas predicts p53 gene status. AB - P53 and p21WAF1/CIP1 (p21) immunostaining was performed on 92 non-Hodgkin's lymphomas (NHLs), and the staining pattern correlated with the presence or absence of p53 hot spot mutations as detected by PCR-SSCP of exons 5-8 and direct sequencing. Twenty-nine of 92 lymphomas overexpressed p53, and 17 overexpressed p21. Of the p53 overexpressing lymphomas, 14 also overexpressed p21, and none of these 14 harbored a detectable hot spot mutation. However, mutations were detected in 13 (87%) of 15 p53 overexpressing, p21 negative lymphomas. One of the 63 p53-negative lymphomas harbored a detectable hot spot mutation, and it was also negative for p21. These results demonstrate that among NHLs that overexpress p53 protein, those which also show p21 overexpression do not harbor p53 hot spot mutations, and furthermore, provide evidence that the transactivating function of p53 is retained. On the other hand, p53 overexpression in NHLs that lack p21 expression is usually indicative of p53 gene mutation. PMID- 9360844 TI - Convenient, nonradioactive, heteroduplex-based methods for identifying recurrent mutations in the BRCA1 and BRCA2 genes. AB - The ability to identify individuals who are predisposed to specific malignant tumors is a promising molecular diagnostic by-product of over two decades of intensive research into the genetic pathogenesis of human cancer. Approximately 2% of Ashkenazi Jews carry recurrent germline mutations in either the BRCA1 or BRCA2 genes that may predispose these individuals to the development of breast and ovarian cancer. We have developed a nonisotopic method, based on the formation of heteroduplexes between polymerase chain reaction (PCR) amplified wild-type and mutant alleles, which can be used to identify the BRCA1 185delAG and the BRCA2 6174delT mutations. The same assay can also be used to verify the loss of heterozygosity in a tumor sample arising in an individual with a germline mutation. The four steps described in this report (PCR amplification, heteroduplex formation, acrylamide gel electrophoresis, and ethidium bromide staining/UV-fluorescence photography) can be readily and reproducibly performed in the course of a single day, making this a useful method for the routine identification of these mutations. PMID- 9360845 TI - Polymerase chain reaction for the detection of Helicobacter pylori in formaldehyde-sublimate fixed, paraffin-embedded gastric biopsies. AB - To improve morphologic detail and immunohistochemical staining, mercuric chloride containing fixatives such as formaldehyde-sublimate (FS) has been widely used as an alternative for neutral buffered formalin. FS-fixed, paraffin-embedded tissue, however, is considered to be an unreliable source of DNA. We used an adapted DNA extraction method for FS-fixed, paraffin-embedded tissue. In all cases tested we obtained amplifiable DNA with polymerase chain reaction (PCR), after FS-fixation and after fixation in neutral buffered formalin as well. A PCR assay for the 16S rRNA region of Helicobacter pylori was developed amplifying a fragment of 145 bp. The specificity of this PCR assay was tested on a range of different microorganisms. PCR was performed on 46 archival FS-fixed paraffin-embedded gastric biopsies. The results were compared with histologic examination and with immunohistochemical detection using a polyclonal antibody against H. pylori. Both PCR and immunohistochemistry are very sensitive methods for the detection of H. pylori. A PCR offers the possibility of additional subtyping in archival FS fixed, paraffin-embedded tissue. PMID- 9360846 TI - Oligoclonal peripheral T-cell lymphocytosis as a result of aberrant T-cell development in a cortical thymoma. AB - A 42-year-old man presented with a locally invasive cortical thymoma. Before chemotherapy was commenced 36 months after presentation, an unusual peripheral lymphocytosis of 19 x 10(9)/l had slowly developed over time. After the first course of chemotherapy, the lymphocytosis showed a sharp decline to normal absolute cell numbers and subsequently remained at normal levels. Currently, the patient is in stable partial remission and doing well. Immunophenotypic analysis showed a mature T-cell phenotype with 78% TcR-a beta and 16% TcR-gamma delta in the absence of an immature component. Pretreatment Southern blot analysis of peripheral blood mononuclear cells showed an oligoclonal pattern with 13-20 rearranged fragments of different intensity for the TcR beta-gene. TcR gamma also showed a pattern compatible with an oligoclonal proliferation. After treatment, after normalization of absolute blood counts, the distribution of T-cell subsets still showed a slightly aberrant pattern. Immunophenotypic analysis of a blood sample taken 6 months later, also at normal absolute cell counts, showed an increase of thymocytes as well as of mature T cells with a polyclonal pattern on Southern blot analysis. These findings may be interpreted as the result of aberrant positive and negative selection and development of thymocytes in the microenvironment of neoplastic thymic epithelial cells and clonal selection through continuous peripheral stimulation. Moreover, this case stresses the importance of integrated interpretation of clinical, morphological, immunophenotypical, and molecular data to gain insight in unusual clinical problems. PMID- 9360847 TI - Snake venoms. AB - Snake venoms are complex mixtures containing many different biologically active proteins and peptides. A number of these proteins act on components of the haemostatic system in humans. The paper focuses on those venom constituents that affect the blood coagulation pathway, endothelial cells and platelets. Several highly purified venom enzymes have been used clinically as anticoagulants, and other venom proteins are being used in preclinical research to investigate their possible therapeutic potential. Haemostatically active components are distributed widely in the venom of many different snake species. In no case are all the components described below found in any single venom. Venom components can be grouped into several categories depending on their haemostatic effect. The following haemostatically active components are discussed in this chapter: enzymes that cause fibrinogen coagulation: enzymes that degrade fibrin(ogen); plasminogen activator; prothrombin activators; factor V activator; factor X activator; anticoagulant activities: enzymes with haemorrhagic activity; platelet aggregation inducers: and platelet aggregation inhibitors. PMID- 9360848 TI - Evaluation of thrombolytic agents. AB - The mechanism of action of currently available thrombolytic agents, such as streptokinase, urokinase, alteplase (recombinant tissue-type plasminogen activator; rt-PA) and anistreplase (anisoylated plasminogen streptokinase activator complex; APSAC), involves conversion of inactive plasminogen to plasmin, a potent fibrinolytic. However, the relatively weak substrate specificity of first generation agents (streptokinase and urokinase) can result in a state of systemic fibrinolysis and associated bleeding complications. The second generation drugs such as alteplase were developed in an attempt to enhance fibrin specificity, so that only enzymatic conversion of fibrin-complexed plasminogen would take place, thus avoiding systemic fibrinolysis. Results from large clinical trials have failed to consistently show any significant differences between first and second generation thrombolytic agents in the incidence of bleeding. In the clinical setting, thrombolytic agents have been evaluated primarily in patients with acute myocardial infarction and have been shown to significantly reduce morbidity and mortality compared with conservative treatment. The focus of current and future research is to investigate these agents in patients with other vaso-occlusive or ischaemic conditions (e.g. stroke), and also to evaluate different drug administration regimens and the use of adjunctive therapies such as aspirin (acetylsalicylic acid) and heparin. PMID- 9360850 TI - Influence of fibrinogen on cardiovascular disease. AB - Results from prevalence, case-control, angiographic and echocardiographic investigations incriminate elevated fibrinogen levels as a strong independent risk factor for the occurrence of initial and recurrent cardiovascular events. Average fibrinogen levels are higher in women and persons with other risk factors including hypertension, diabetes, cigarette smoking, obesity, elevated haematocrit value and dyslipidaemia. Fibrinogen tends to cluster with most of these major atherogenic cardiovascular risk factors and further enhances their risk. Prospective data indicate a relationship between fibrinogen and the subsequent development of all the major atherosclerotic cardiovascular events including coronary heart disease, stroke and peripheral artery disease. Fibrinogen adds to the multivariate risk of cardiovascular events, especially in the high risk subset of the population. In the Framingham Heart Study, a comparison of risk gradients, exemplified by their regression coefficients, was similar for all outcomes (coronary heart disease, stroke, peripheral artery disease and cardiovascular disease) in men, whereas, in women, the risk gradient for fibrinogen appeared weakest for stroke. Fibrinogen exerts an independent influence on the frequency of cardiovascular disease in general, and coronary heart disease in particular. For example, in both men and women, each standard deviation increase in fibrinogen level (about 0.56 g/L) within the range of usual values is associated with about a 20% age- and risk factor-adjusted increase in the incidence of an initial cardiovascular event. Fibrinogen should be added to the list of major atherogenic cardiovascular risk factors; in addition, there is a need for intervention trials designed to test the efficacy of lowering fibrinogen in individuals at high risk for cardiovascular disease. PMID- 9360849 TI - Defibrinogenating enzymes. AB - The venoms from 3 snakes have been shown to induce defibrinogenation: ancrod from the venom of Calloselasma rhodostoma (formerly known as Agkistrodon rhodostoma), batroxobin from the venom of Bothrops atrox moojeni, and crotalase from the venom of Crotalus adamanteus. The purified fractions of ancrod, batroxobin, and crotalase possess coagulant, proteolytic and esterolytic properties, although their primary mechanism of action is a proteolytic effect on circulating fibrinogen. Ancrod cleaves only the A-fibrinopeptides, but not the B fibrinopeptides, from fibrinogen; this contrasts with thrombin, batroxobin and crotalase, which cleave both fibrinopeptides A and B. Within minutes of administration of ancrod or batroxobin, there is a significant reduction in plasma fibrinogen levels, and these remain exceedingly low with repeated administration (once or twice daily). The rapid fall in plasma fibrinogen levels is accompanied by a slightly delayed but marked rise in the level of fibrinogen fibrin degradation products. Plasminogen levels are decreased and blood viscosity is reduced, but formed elements in the circulating blood remain unaltered. Ancrod and batroxobin have been investigated in patients with stroke, deep-vein thrombosis, myocardial infarction, peripheral arterial thrombosis, priapism, and sickle-cell crisis; crotalase has not been administered to humans. However, results have been difficult to interpret, and additional well designed trials are needed to better define the optimum role of ancrod and batroxobin in the management of these conditions. Overall, treatment is well tolerated and serious adverse events are infrequent. In the coagulation laboratory, ancrod, batroxobin and crotalase may be used as reagents to perform coagulation studies on specimens of blood that contain heparin. These venom fractions can be substituted for thrombin in performing the thrombin time and in removing fibrinogen from plasma for accurate determination of fibrinogen-fibrin degradation products. PMID- 9360852 TI - The medical economics of stroke. AB - The economic consequences of the approximately 500,000 strokes that occur each year in the US are staggering. The direct cost of providing care for stroke victims in 1993 has been estimated to be $US17 billion, with an additional $US13 billion in indirect costs attributable to lost earnings due to stroke-related mortality and morbidity. Estimates of the cost of stroke over a patient's lifetime vary according to age at first stroke and type of stroke. In 1990, these estimates ranged from $US91,000 for ischaemic stroke, $US124,000 for intracerebral haemorrhage, and $US228,000 for subarachnoid haemorrhage. Factors driving the economics of stroke include the epidemiology of stroke, treatment patterns and settings, and social and behavioural factors. Evaluating the economic consequences of alternative interventions designed to prevent strokes or improve stroke outcomes involves a weighing of incremental costs and effectiveness. Previous efforts have focused primarily on measuring costs, with a recent shift to trying to measure patient preferences for stroke outcomes. PMID- 9360851 TI - Endothelial dysfunction and atherothrombotic occlusive disease. AB - The endothelium plays a crucial role in the regulation of vascular function through the release of locally important molecular effectors such as endothelium derived relaxing factor (EDRF) and prostacyclin. Endothelial cells also regulate vascular patency and tissue perfusion by inhibiting platelet aggregation and thrombosis, suppressing intimal proliferation, and maintaining vascular tone. Disturbances of the regulatory functions of the endothelium contribute to the pathophysiology of various disease states, including cardiovascular disease and stroke. Most studies focused on endothelial control of vasomotion and, in particular, on the action of EDRF; many studies have also emphasised that altered endothelial control of fibrinolysis and intimal growth influence the clinical expression of atherothrombotic disease. Importantly, understanding the pathophysiological role of endothelial dysfunction may lead to new therapeutic approaches for disease states caused by vascular disease. PMID- 9360853 TI - Management of patients with acute ischaemic stroke. AB - The management of patients with acute ischaemic stroke, which was once accompanied by a sense of futility, has shifted to emergency intervention, as a result of clinical trials demonstrating the efficacy of acutely administered therapies in reducing mortality and morbidity. The current approach to stroke thus emphasises early recognition, rapid transport to hospital, speedy evaluation and urgent treatment. In the emergency room, treatment decisions are largely influenced by the neurological status of patients, although their respiratory, cardiovascular and metabolic status are also considered. Initially, efforts are aimed at reducing hypoxia and hypercarbia, controlling symptoms such as pain or vomiting, and reducing the morbidity and mortality associated with stroke. Most patients with stroke require hospitalisation; in-hospital care continues to focus on preventing and controlling subacute and chronic complications, but also includes planning for rehabilitation and care after discharge, and treatment to prevent recurrent stroke. Administration of newer treatment interventions, such as thrombolytic therapy, requires the availability of teams of stroke specialists; furthermore, the management of stroke patients in a dedicated unit has been shown to reduce death and disability and to shorten the hospital stay. While therapies aimed at reducing the neurological consequences of stroke are the keystone of current and future care, the control of acute, subacute, or chronic medical and neurological complications, prevention of recurrent stroke, and rehabilitation to maximise recovery from stroke remain crucial components of patient management. PMID- 9360854 TI - Manipulation of coagulation factors in acute stroke. AB - In patients with an acute cerebral infarction, anticoagulation may spare tissue in the ischaemic penumbra from irreversible necrosis by preventing thrombus extension from a vascular bed with good collateral circulation to one with poor collateral circulation. In addition to the possibility of limiting infarct volume, anticoagulation may be given acutely to prevent early recurrent cerebral infarction or to prevent or treat thrombus outside the nervous system (i.e. deep venous thrombosis or pulmonary embolus). In one controlled trial of a low molecular weight heparin, administration of nadroparin calcium within 48 hours of onset of cerebral infarction decreased the combined incidence of dependency and all-cause mortality at 6 months. Another controlled trial in patients with cerebral venous thrombosis demonstrated the benefit of continuous intravenous adjusted-dose unfractionated (UF) heparin compared with placebo. Although results of anticoagulation appear promising in patients with acute cerebral infarction and cerebral venous thrombosis, the benefits of these agents remain unconfirmed. The results of large multicentre trials using a heparinoid (ORG 10172) and subcutaneous UF heparin in patients with acute cerebral infarction are expected within the year. PMID- 9360855 TI - Neuroprotective therapies in stroke. AB - Neuroprotective drugs are known to reduce neurological damage in animal models of stroke, but none are generally accepted for the treatment of patients with acute stroke. Thrombolytic therapy with alteplase (recombinant tissue-type plasminogen activator; rt-PA) has been shown to improve outcomes in patients with stroke, but it must be given quite rapidly after stroke onset. The efficacy of alteplase therapy has proven that acute treatment is possible, and methods used in those trials will be applicable to neuroprotective development. A variety of neuroprotective drugs have already been tested and more trials are likely. Glutamate antagonists have been most extensively evaluated, but they are relatively disappointing since they have phencyclidine-like adverse events that limit the tolerable doses. Several other classes of neuroprotectives are in development, although their mechanisms of action are not well established. Combinations of neuroprotectives and thrombolytics are likely to be tested in clinical trials in the near future. PMID- 9360857 TI - Ancrod in the treatment of acute ischaemic stroke. AB - Ancrod converts fibrinogen into soluble fibrin products, resulting in a decrease in plasma fibrinogen and blood viscosity, and also induces the release of endogenous tissue-type plasminogen activator from the vessel wall. These activities suggest that treating patients with acute ischaemic stroke with ancrod might result in improved cerebral blood flow and patient outcome. Two large randomised placebo-controlled studies have evaluated treatment with ancrod in patients with acute ischaemic stroke. In the first, patients were treated within 6 hours of symptom onset: this was not successful in quickly lowering fibrinogen levels to the target range (0.7 to 1.0 g/L) and the results were inconclusive. However, a post hoc analysis suggested that treatment with ancrod was effective in patients whose fibrinogen level was reduced to less than 1.3 g/L within 6 hours of starting treatment. A second larger study is still in progress, but preliminary results in patients treated within 3 hours of onset of ischaemic stroke are available and indicate that the target fibrinogen level of less than 1 g/L within 6 hours of instituting treatment is being achieved in most patients. PMID- 9360856 TI - Thrombolytic therapy in the treatment of stroke. AB - Approximately 80 to 90% of cerebral ischaemic events that occur within 24 hours of symptom onset are due to atherothrombotic or thromboembolic occlusions. This forms the rationale for the use of thrombolytic agents in patients with acute ischaemic stroke. Early studies determined that recanalisation occurred in approximately 21 to 72% of patients with occluded cerebral arteries after intra arterial or intravenous administration of streptokinase, urokinase, alteplase (recombinant tissue-type plasminogen activator; rt-PA) or duteplase (a 2-chain rt PA). Initial reports suggested that frequencies of haemorrhagic transformation and parenchymatous haematoma in the carotid territory were similar whether patients with middle cerebral artery stroke received thrombolysis via intra arterial or intravenous administration. The Multicentre Acute Stroke Trial-Europe (MAST-E), the Australia Streptokinase (ASK), and the Multicentre Acute Stroke Trial-Italy (MAST-I) trials, which evaluated intravenous streptokinase 1.5 x 10(6) IU in patients with acute ischaemic stroke, were terminated prematurely because of excessive early mortality and symptomatic intracranial haemorrhage in streptokinase recipients compared with those treated with placebo. However, those studies had not been preceded by dose-ranging trials. Intravenous administration of alteplase 0.9 mg/kg within 3 hours [National Institute of Neurological Disorders and Stroke (NINDS) trial], or 1.1 mg/kg within 6 hours [European Cooperative Acute Stroke Study (ECASS)], of symptom onset in patients with acute ischaemic stroke resulted in an absolute 11 to 13% treatment-associated improvement in clinical measurement scales; such as the modified Rankin scale and Barthel index, compared with placebo recipients. In the ECASS trial, those results were limited to a 'target population' restricted to those who satisfied all entry criteria. In both trials, the frequency of symptomatic haemorrhage was greater in patients treated with alteplase than with placebo and reinforced the importance of careful patient selection. Strict patient selection remains central to the success of this approach. PMID- 9360858 TI - Logistics in acute stroke management. AB - Results from the two National Institute of Neurological Disorders and Stroke (NINDS) studies indicate that administration of alteplase (recombinant tissue type plasminogen activator; rt-PA) within 3 hours of symptom onset to appropriately selected patients with acute ischaemic stroke improves patient outcome. Several factors that delay time to treatment in patients with stroke have been identified, the most important of which is probably the failure of the patient (or family member) to recognise the signs and symptoms of stroke. Once the need for help is recognised, the initial point of access to emergency medical systems should be the local emergency number (e.g. 911 in the US) rather than the family physician. Patients with suspected stroke should be evaluated and treated by a physician as soon as possible, but this will depend to some extent on the level of expertise of the attending physicians and on available resources. The NINDS-sponsored National Symposium on the Rapid Identification and Treatment of Acute Stroke has recommended ideal time goals for all hospitals that treat patients with acute stroke. These goals include 25 minutes from arrival at an emergency department to computerised tomography scan, and 60 minutes from arrival to treatment. Recommendations for enhancing the logistics of treatment for patients with stroke may involve the following: improved education programmes for at-risk populations and their families and emergency medical system personnel, identification of acute stroke as a level one emergency similar to acute myocardial infarction or trauma, and modelling of treatment algorithms accordingly, acceptance of, and commitment to, the time guidelines recommended by the National Symposium on the Rapid Identification and Treatment of Acute Stroke. Effective and safe use of alteplase will also depend on rapid access to the highest level of neurological and radiological expertise. This may require major changes in the educational curriculum of emergency department residency and ongoing continuing education programmes, and/or more intensive radiological training for neurologists and neurologists-in-training. PMID- 9360859 TI - Psychological characteristics of child cochlear implant candidates and children with hearing impairments. AB - OBJECTIVE: To describe the psychological status of deaf children with hearing parents who were seeking a cochlear implant and to compare them with deaf children with hearing parents who were not seeking a cochlear implant. DESIGN: A sample of children consecutively referred for a cochlear implant at the University of Iowa Hospitals and Clinics was contrasted on a number of standardized psychological measures with a cohort of children from Boys Town National Research Hospital, who had hearing impairments and whose families had not sought a cochlear implant. RESULTS: Although the comparison group evidenced more externalizing and social problems than the implant group, the means of both groups fell well within the normal range. Similarly, although mothers of the implant group rated their child's home as characterized by more positive and supportive interactions than did mothers of the children in the comparison group, both group means were well within the average range. On measures of intelligence, the two groups also did not differ. CONCLUSION: Overall, the study indicated that children with hearing impairments and their families who were seeking cochlear implants are not significantly different from children with hearing impairments whose parents were not seeking a cochlear implant. The results provided no support for the notion that children with hearing impairments from families seeking a cochlear implants for their child evidence more behavioral deviance than children with hearing impairments whose parents have not sought an implant. PMID- 9360860 TI - Labeling of musical interval size by cochlear implant patients and normally hearing subjects. AB - OBJECTIVE: To compare the performance of cochlear implant patients and normal hearing subjects on a musical interval labeling task, and to determine whether information regarding musical interval size is available to cochlear implant patients under realistic everyday listening conditions. DESIGN: Two Nucleus cochlear implant patients listened to musical intervals that consisted of systematic variations of electric pulse rate on single bipolar intracochlear electrode pairs, whereas normal-hearing listeners were presented with the acoustical analog of these stimuli. Subjects labeled the intonation quality of the stimulus intervals ("flat," "sharp," or "in tune"), relative to their memory for specific intervals abstracted from familiar melodies. The cochlear implant patients, in addition, performed this task with realistic acoustical musical stimuli. RESULTS: The interval labeling behavior of cochlear implant subjects, at low pulse rates, was similar to that of normal-hearing subjects. Furthermore, pitch interval information does not appear to be available to cochlear implant subjects when they are listening to acoustical stimuli via their speech processors. CONCLUSIONS: Temporal information appears to be sufficient for the perception of musical pitch. Encoding strategies that are highly successful in restoring speech understanding do not necessarily provide information regarding melodic pitch interval size. PMID- 9360861 TI - A digital filterbank hearing aid: three digital signal processing algorithms- user preference and performance. AB - OBJECTIVE: Three digital signal processing algorithms named RangeEar, DynEar, and LinEar were compared with regard to user preference and performance when a wearable digital filterbank hearing aid was used. All three algorithms provided individual frequency shaping via a seven-band filterbank. Compression was used in a low-frequency (LF) and a high-frequency (HF) channel. RangeEar and DynEar used wide dynamic range syllabic compression in the LF channel, whereas LinEar used compression limiting. In the HF channel, RangeEar used a slow acting automatic volume control, whereas DynEar and LinEar used compression limiting. The subjects had access to a manual volume control when using the LinEar or DynEar options. DESIGN: The study included 13 hearing aid users with symmetrical sensorineural losses. In a 1 mo long blind field test, the RangeEar algorithm was compared with the preferred algorithm from an earlier study, DynEar or LinEar. A data logger function was included for objective recording of the total time each algorithm was used and how the volume controls were used. The preference was based on the time used for each algorithm and from subjective statements. Threshold signal-to noise ratio (S/N-threshold) for speech was tested, and sound quality ratings were obtained through a questionnaire. RESULTS: Of the 13 subjects, six preferred the RangeEar fitting and another four preferred the DynEar fitting. Two subjects preferred the LinEar fitting and one had equal preference for RangeEar and LinEar. The results from the questionnaire showed that the preferred fittings were rated higher concerning overall impression of sound quality and clearness, whereas the S/N for the speech test did not show any differences. Preferences, where stated, could be predicted from auditory dynamic range measurements in the LF and HF frequency ranges. The mean dynamic range was broader for low and narrower for high frequencies for those who preferred the RangeEar or DynEar fitting as compared with those who preferred the LinEar fitting. The preference between RangeEar and DynEar was predicted by differences in the HF range, with the narrower dynamic range for the DynEar preference subjects. CONCLUSION: Most subjects preferred the option of having a wide dynamic range syllabic compressor in the LF channel and having the overall gain in the HF channel adjustable, either manually (DynEar) or automatically (RangeEar). PMID- 9360862 TI - The contour test of loudness perception. AB - OBJECTIVE: This article presents the underlying rationale, normative data, and reliability data for a test of loudness perception (the Contour Test) that was devised for use in clinical hearing aid fitting. The Contour Test yields data describing the sound level required for each of seven categories of loudness ranging from very soft to uncomfortably loud. DESIGN: Two experiments are described. Experiment 1 yielded norms for the test. The subjects were 23 male and 22 female normal-hearing listeners. Test stimuli included warble tones at six frequencies and broad band speech. Experiment 2 assessed the reliability of the test results. Ten hearing-impaired listeners responded to the test at two frequencies on two occasions separated by several days. Both experiments also evaluated the effect of using different stimulus increment sizes on the measured levels of loudness categories. RESULTS: Based on the data from experiment 1, norms for each category of each stimulus are reported in terms of mean level and typical between-subject variation in responses. Data are provided in HA-12 cm3 coupler levels as well as in hearing levels (dB HL). The shape of the loudness growth function for warble tones was somewhat different from that for speech. When data were expressed in HL, there were no differences in mean loudness category levels across warble tone test frequencies. Thus, test frequencies were combined and equations were generated to describe the upper and lower limits of typical normal performance for warble tone stimuli. These equations can be used to construct a template for clinical comparison of normative values to patient loudness growth curves. Experiment 2 provided information about the test-retest variability of data yielded by the Contour Test. Reliability appears to be similar to that of the few other category scaling tests described in the literature. Most test-retest differences were 6 dB or less. Although a moderate variation in test increment size did not significantly affect the loudness category levels for young normal-hearing listeners, levels corresponding to loudness categories were significantly higher when larger increments were used with elderly hearing-impaired listeners. CONCLUSIONS: Evidence from this and other research indicates that standardized measurement of loudness perception is an achievable goal for clinical practice. The Contour Test appears to offer a viable approach to clinical measurement of loudness perception: It has good patient acceptance and combines fairly rapid administration with acceptable reliability. Details of test procedures and scoring sheets for manual administration can be downloaded from the Internet at www.ausp.memphis.edu/harl. However, it is important to keep in mind that the application of loudness perception data for narrowband stimuli (such as warble tones) to hearing aid prescription is complicated by the need to account for the effects of loudness summation across bandwidth. There is a need for additional research to establish an empirical link between clinically measured loudness perception and optimal amplification characteristics. PMID- 9360863 TI - Effects of test procedure on individual loudness functions. AB - OBJECTIVE: To determine if measurement procedure effects occur for loudness perception data measured using a categorical rating scale. DESIGN: Loudness data were obtained from 40 normal-hearing adult volunteers, using 30 levels of pure tones at four frequencies (500, 1000, 2000, and 4000 Hz), with judgments made on a 9-point categorical scale. Two presentation orders, random and sequential, were compared within subjects. Subjects were divided into two groups: one group heard only a single tone on every trial, whereas the other group was presented with a maximum level reference tone at the start of each trial. RESULTS: A significant difference was found between loudness function exponents measured with the random and sequential presentation order of stimulus level. A significant difference was found between loudness function exponents measured when a high-level referent was presented at the start of each trial. The sequential presentation order was further subdivided into ascending and descending runs, and the loudness function exponents for each run were examined separately. The results showed a significant interaction between sequence (ascending versus descending) and group. CONCLUSIONS: For normal-hearing listeners, the procedure used to measure loudness has an effect on the loudness function exponent obtained. These results appear to be related to stimulus context effects. Loudness function exponents are smaller when the stimulus is preceded by a stimulus level greater than the level of the test tone. This occurred when a high-level referent was presented at the start of each trial or when the stimulus level from the previous trial was greater than the test level, as in a descending run. It seems likely that the difference between loudness function exponents obtained with a random and sequential presentation of level can be explained by the same phenomenon. The significance of these results for hearing aid fittings in which loudness normalization is the goal is discussed. PMID- 9360865 TI - Comparison of statistical indicators for the automatic detection of 80 Hz auditory steady state responses. AB - OBJECTIVE: To evaluate, using receiver operation characteristic (ROC) curves, the performance of several statistical indicators in the objective detection of 80 Hz steady state auditory evoked responses. DESIGN: Steady state auditory evoked responses elicited by amplitude modulated tones of 500 and 1000 Hz, were obtained in 16 normal adults. Recordings were made at intensities ranging from 80 to 30 dB SPL and without stimulation. Four statistics: coherence synchrony measure, circular T2, a new variant of Hotelling T2 (labeled HT2) and a test for hidden periodicity (F test) were calculated. The statistics were compared using ROC curves and bootstrapping techniques. Two outcome measures were considered: behavioral threshold prediction and averaging efficiency. RESULTS: All indicators were highly accurate to detect a response (8 to 9 dB above mean behavioral threshold for the 1000 Hz and 14 to 16 dB for the 500 Hz carrier). Responses could be reliable detected after averaging about five individual epochs of long duration. No statistically significant differences were evidenced though in their capability to predict behavioral threshold or their averaging efficiency. CONCLUSIONS: Despite the more adequate statistical properties of some of these indicators no significant differences were found in their performance. Thus all of these indicators could be recommended for automatic detection of 80 Hz auditory steady state responses. PMID- 9360864 TI - The relationship between loudness intensity functions and the click-ABR wave V latency. AB - OBJECTIVE: To assess the relationship of loudness growth and the click-evoked auditory brain stem response (ABR) wave V latency-intensity function (LIF) in listeners with normal hearing or cochlear hearing loss. The effect of hearing loss configuration on the intensity functions was also examined. DESIGN: Behavioral and electrophysiological intensity functions were obtained using click stimuli of comparable intensities in listeners with normal hearing (Group I; n = 10), and cochlear hearing loss of flat (Group II; n = 10) or sloping (Group III; n = 10) configurations. Individual intensity functions were obtained from measures of loudness growth using the psychophysical methods of absolute magnitude estimation and production of loudness (geometrically averaged to provide the measured loudness function), and from the wave V latency measures of the ABR. RESULTS: Slope analyses for the behavioral and electrophysiological intensity functions were separately performed by group. The loudness growth functions for the groups with cochlear hearing loss approximated the normal function at high intensities, with overall slope values consistent with those reported from previous psychophysical research. The ABR wave V LIF for the group with a flat configuration of cochlear hearing loss approximated the normal function at high intensities, and was displaced parallel to the normal function for the group with sloping configuration. The relationship between the behavioral and electrophysiological intensity functions was examined at individual intensities across the range of the functions for each subject. A significant relationship was obtained between loudness and the ABR wave V LIFs for the groups with normal hearing and flat configuration of cochlear hearing loss; the association was not significant (p = 0.10) for the group with a sloping configuration of cochlear hearing loss. CONCLUSION: The results of this study established a relationship between loudness and the ABR wave V latency for listeners with normal hearing, and flat cochlear hearing loss. In listeners with a sloping configuration of cochlear hearing loss, the relationship was not significant. This suggests that the click-evoked ABR may be used to estimate loudness growth at least for individuals with normal hearing and those with a flat configuration of cochlear hearing loss. Predictive equations were derived to estimate loudness growth for these groups. The use of frequency-specific stimuli may provide more precise information on the nature of the relationship between loudness growth and the ABR wave V latency, particularly for listeners with sloping configurations of cochlear hearing loss. PMID- 9360866 TI - Psychometric functions for the CID W-22 and NU Auditory Test No. 6. Materials spoken by the same speaker. AB - The equivalence was determined for the W-22 and NU No. 6 lists recorded with the same carrier phrase and by the same speaker (Auditec compact disc). For presentation, the lists were interleaved to form lists of 100 words. In Experiment 1, the materials were presented in quiet (0 to 30 dB HL) and in 60 dB SPL speech-spectrum noise (35 to 65 dB HL) at 5 dB intervals to 24 subjects with normal hearing. In Experiment 2, the materials were presented at two levels 10 dB apart to 24 subjects with sensorineural hearing loss. Recognition performance was on average 4 to 8% better on NU No. 6 materials than on the W-22 materials, a difference that was significant for both subject groups. The 2 to 4 dB differences are within the 5 dB steps typically used clinically and are not considered of clinical significance. PMID- 9360867 TI - Prospective screening of dyspeptic patients by Helicobacter pylori serology: a safe policy? The Italian Helicobacter pylori Study Group. AB - BACKGROUND AND STUDY AIMS: Endoscopic screening of all dyspeptic patients is not cost-effective, nor is it feasible in many health-care delivery systems. To select the most appropriate candidates, various preendoscopic screening strategies have been proposed, some of which include Helicobacter pylori serology and patient age. We assessed the value of these two criteria in preendoscopic screening of a large series of dyspeptic patients, and compared the results obtained in a referral hospital (university center with an extensive H. pylori research program) with those in nonreferral hospital (participating centers that did not have such a program). PATIENTS AND METHODS: Blood samples for determination of anti-H. pylori IgG antibody were collected from patients with uninvestigated dyspepsia undergoing endoscopy at one referral hospital and in 93 nonreferral hospitals throughout Italy. For IgG antibody assay, an in-house enzyme-linked immunosorbent assay (ELISA) technique was used in the referral hospital, while a commercial kit was used in the nonreferral hospitals. RESULTS: A total of 1638 patients were evaluated at the referral hospital (845 men and 793 women, mean age 46.1 years, range 18-89), and 3281 at the nonreferral hospitals (1718 men and 1563 women, mean age 48.8, range 18-96), respectively. If endoscopy had not been performed in patients who were seronegative for H. pylori and younger than 45 years, 19% versus 17.5% of the tests would have been avoided in the referral and nonreferral hospitals, respectively, while six of 304 ulcers (2%) and no cancers would have been missed versus 35 of 557 ulcers (6.3%) and two of 557 cancers (0.3%). CONCLUSIONS: A screening strategy based on age and H. pylori serology is a valid means of selecting dyspeptic patients for endoscopy; however, the policy needs further refinement for use in nonreferral hospitals. PMID- 9360869 TI - Laparoscopic common bile duct exploration after failed endoscopic stone extraction. AB - BACKGROUND AND STUDY AIMS: Despite the documented success rate and safety of laparoscopic ductal stone extraction, the majority of patients are treated with preoperative endoscopic stone extraction followed by laparoscopic cholecystectomy. When this fails, conventional open cholecystectomy and common bile duct exploration are performed. We report here a series of patients who were treated laparoscopically after failed attempts at endoscopic stone extraction. PATIENTS AND METHODS: Nineteen patients (12 women and seven men, aged 41-96 years) were treated laparoscopically. Four had undergone previous cholecystectomy. ERCP had been attempted in all patients, was unsuccessful in three patients, and had been interpreted as normal in two. Endoscopic stone extraction had been attempted in 14 patients. The mean follow-up period was 23 months, range 1-54 months. RESULTS: Ductal calculi were confirmed in 18 patients with successful and complete laparoscopic ductal clearance in 15 (83%), two of whom underwent an additional laparoscopic choledochoduodenostomy due to a large stone load and a grossly dilated common bile duct. Conversion to open surgery was required in three cases (17%). Ductal clearance at a single operation was achieved in all 18 patients. There were no postoperative deaths, but two patients developed postoperative complications (11% morbidity), one requiring laparotomy. The median postoperative hospital stay was five days, range 4-41 days. Recurrence of calculi was encountered in one patient. CONCLUSIONS: Laparoscopic ductal stone clearance after failed endoscopic stone extraction is successful in the majority of patients, and should be attempted prior to recourse to open surgery, provided the necessary laparoscopic biliary expertise is available. PMID- 9360868 TI - A prospective evaluation of the diagnostic work-up before laparoscopic cholecystectomy. AB - BACKGROUND AND STUDY AIMS: A prerequisite for successful laparoscopic cholecystectomy is the exclusion of potential risks such as cholangiolithiasis or anatomical malformations. As there is no general agreement regarding the appropriate preoperative diagnostic work-up, a comparative study of different diagnostic methods was carried out. PATIENTS AND METHODS: In 180 consecutive patients admitted to a community hospital for cholecystectomy due to symptomatic cholecystolithiasis, a prospective comparison was carried out of the diagnostic accuracy of patient history, physical examination, laboratory tests, upper gastrointestinal endoscopy, intravenous cholangiography, ultrasonography, and endoscopic retrograde cholangiopancreatography (ERCP). RESULTS: Measurement of the diameter of the common bile duct was found to be a reliable method as a single noninvasive parameter for diagnosing cholangiolithiasis (sensitivity 100%, specificity 93%), with good predictive power (positive predictive value 0.7, negative predictive value 1.0). The best accuracy achieved noninvasively and without sonography was with a combination of positive patient history and gamma glutamyl transferase findings (sensitivity 58%, specificity 84%, positive predictive value 0.37, negative predictive value 0.93). ERCP detected additional cholangiolithiasis in 19 of 139 patients (13.7%) and anatomical malformations in three patients. In all 19 patients, the bile ducts were cleared of stones endoscopically within 24 hours, prior to laparoscopic cholecystectomy. Among the 163 patients primarily assigned to laparoscopic cholecystectomy, the protocol diagnostic work-up, including ERCP, allocated three patients (1.8%) to open surgery. Conversion from laparoscopic cholecystectomy to open cholecystectomy occurred in a further two of 158 patients (1.3%). CONCLUSIONS: These results show that routine ultrasonography prior to laparoscopic cholecystectomy can be recommended in order to determine the diameter of the common bile duct. In patients with a ductal diameter of more than 6 mm, ERCP should be performed. Laparoscopic cholecystectomy can be carried out within 24 hours after ERCP and papillotomy. PMID- 9360870 TI - Endoscopic ultrasonography: a promising method for assessing the prospects of endoscopic mucosal resection in early gastric cancer. AB - BACKGROUND AND STUDY AIMS: A recent challenge that is increasingly being faced in endoscopy is the use of endoscopic mucosal resection (EMR) to treat differentiated intramucosal gastric cancers smaller than 2 cm. The usefulness of pretherapeutic endoscopic ultrasonography (EUS) in assessing whether this form of treatment is possible remains controversial. PATIENTS AND METHODS: We retrospectively investigated the value of pretherapeutic EUS evaluation in 58 patients with macroscopically early gastric cancer that was histologically differentiated and less than 2 cm in diameter. The patients were classified as negative for endoscopic mucosal resection if EUS showed modifications of the third layer, and as positive if such modifications were not seen. All patients underwent radical surgery and the preoperative EUS findings were compared with the histological findings. RESULTS: The prevalence of metastatic adenopathy was 3% (two of 58). In the lymph-node staging, endosonography had a sensitivity of 0% (neither of two cases), and a specificity of 93% (52 of 56). In assessing the indication for EMR, EUS had a sensitivity of 93% (27 of 29), and a specificity of 86% (25 of 29). CONCLUSIONS: These results suggest that EUS is a promising method of evaluating the indication for endoscopic mucosal resection in early gastric cancer. EUS may improve pretherapeutic prediction of tumor curability by EMR, and may reduce the need for standard gastrectomy. PMID- 9360871 TI - Interobserver agreement in the staging of rectal cancer using endoscopic ultrasonography. AB - BACKGROUND AND STUDY AIMS: In rectal tumors invasion of the rectal fat and perirectal lymph nodes are generally regarded as independent prognostic factors in most prospective series. There are no studies in the literature concerning interobserver agreement on the staging of rectal cancer by endorectal ultrasonography (EUS). The aim of the present study was to assess interobserver agreement using EUS in the TN staging of rectal cancer. PATIENTS AND METHODS: Thirty-seven patients with rectal cancer were investigated at two centers using EUS as part of the pretherapeutic staging (Olympus EUM-3 or EUM-20). All examinations were videotaped and reviewed six months later by four independent observers who assessed the stage of the tumor (from uT1 to uT4) and lymphatic invasion on a blinded basis. When the tumor was assessed as uT3, the observers specified the degree of involvement of the rectal fat (in millimeters). Interobserver agreement was estimated using the kappa coefficient (k) and the intraclass correlation coefficient (ICC). Agreement was classed as poor (k < 0.40), fair to good (0.40 < or = k < 0.75) or excellent (k < or = 0.75). RESULTS: Agreement was fair for uT1 tumors (k = 0.40) and poor for uT2 tumors (k = 0.20). Agreement was good (k = 0.58; CI 0.51 to 0.65) for uT3 tumors; there was a significant interobserver correlation for the exact measure of the extent of rectal fat (ICC = 0.65). The agreement was also good (k = 0.54, CI 0.47 to 0.61) for metastatic lymph nodes. CONCLUSION: As in the case of esophageal cancer, interobserver agreement on the staging of uT2 tumors is poor with EUS. The evaluation of rectal tumors with a poor prognosis shows good interobserver agreement. PMID- 9360872 TI - Invasive carcinoma in colorectal adenomas: multivariate analysis of patient and adenoma characteristics. AB - BACKGROUND AND STUDY AIMS: The risk of invasive carcinoma developing in colorectal adenomas is influenced by a number of characteristics, relating both to the patients and to the adenomas, and by the composition of the sample analyzed. The aim of the present study was use a multivariate analysis to investigate the risk of invasive carcinoma in endoscopically and surgically removed adenomas. PATIENTS AND METHODS: Between 1978 and 1993, more than 20,000 polyps were prospectively documented at the Erlangen Registry of Colorectal Polyps. A multivariate analysis of 11,188 adenomas detected at the first total colonoscopy was carried out in order to investigate the risks associated with size and site--both of which can be assessed by endoscopic inspection alone- and the extent to which these may be modified by other patient and adenoma characteristics, with an influence on the risk of invasive carcinoma in colorectal adenomas. RESULTS: The size of the adenoma proved to be the most important influencing factor. Invasive carcinoma was never found in 5027 small adenomas (< or = 5 mm). Adenomas in the right colon had a lower risk than those in the left colon or rectum. But with increasing adenoma size, the malignancy rate showed a right-sided shift, with a significant interactive effect of size and right-sided location. However, the risk determined by the size and site of the adenoma was significantly modified by a number of patient and adenoma characteristics, including histological type, presence of multiple adenomas, and patient age and sex. CONCLUSIONS: The risk of invasive carcinoma in colorectal adenomas can only be adequately described by a complex model of the interactive effects of patient and adenoma characteristics on the main factors of size and site. PMID- 9360873 TI - Virtual computed tomography gastroscopy: a new technique. AB - BACKGROUND AND STUDY AIMS: The aim of the present study was to establish a suitable method for virtual computed tomography (CT) gastroscopy. PATIENTS AND METHODS: Three-millimeter helical CT scans of a pig stomach were obtained after air insufflation and instillation of diluted diatrizoic acid (Gastrografin), and with double contrast. In addition, three patients with gastric tumors were studied after ingestion of an effervescent agent (Duplotrast, 6 g) and intravenous injection of hyoscine butylbromide (Buscopan, 1 ml). Virtual endoscopy images were computed on a Sun Sparc 20 workstation (128 megabytes of random access memory, four gigabytes of hard disk space), using dedicated software (Navigator, General Electric Medical System Company). The endoscopy sequences were compared with real endoscopic examinations and with anatomical specimens. RESULTS: In the cadaver studies, the best results were obtained with plain air insufflation, whereas virtual CT gastroscopy with diluted contrast and with double contrast showed artifacts simulating polyps, erosions, and flat ulcers. Patient studies showed good correlation with the fiberoptic endoscopy findings, although large amounts of retained gastric fluid substantially reduced the quality of the surface reconstruction. CONCLUSION: These preliminary results show that virtual CT gastroscopy is able to provide insights into the upper gastrointestinal tract similar to those of fiberoptic endoscopy. However, due to the limited spatial resolution of the CT protocol used, as well as inherent image artifacts associated with the Navigator program's reconstruction algorithm, the form of virtual CT gastroscopy studied was not capable of competing with the imaging quality provided by fiberoptic gastroscopy. PMID- 9360874 TI - Contrast-enhanced endoscopic ultrasonography with galactose microparticles: SHU508 A (Levovist). AB - BACKGROUND AND STUDY AIMS: To evaluate the utility of a suspension of galactose microparticles available as SHU508 A (Levovist) as a contrast agent during endoscopic ultrasonography (EUS). MATERIALS AND METHODS: Three sets of experiments were performed on three 20-25 kg swine (Sus scrofa) under general anesthesia. Upper EUS was performed with an echo endoscope with color Doppler capability (Pentax FG-32 UA). The celiac artery, superior mesenteric artery, aorta, portal vein, pancreas, and gastrointestinal wall were imaged by EUS. Multiple intravenous bolus injections of 400 mg/ml of SHU508 A were made, and their effect on color Doppler and gray-scale imaging during EUS was studied. RESULTS: After contrast injection there was a significant, visually noticeable enhancement of the color Doppler signals from the celiac artery, superior mesenteric artery, and portal vein. Vessels with weak to no color Doppler signals before injection of SHU508 A--for example, the celiac artery and superior mesenteric artery--were observed to have strong color signals after injection. The effect of SHU508 A on color Doppler imaging was easily appreciated subjectively without the need for complex quantitative measurements. No visually noticeable color Doppler enhancement was seen in vessels such as the aorta that had a very pronounced color Doppler signal even prior to the injection of contrast. Movement of particulate matter was seen in the portal vein on the gray scale. CONCLUSION: Intravenous SHU508 A as a contrast agent significantly enhances color Doppler signals during EUS. Vascualar contrast of this sort could potentially have a significant role in improving the accuracy of EUS in diagnosing malignant vascular invasion, the detection of occult pancreatic neoplasms, and the diagnosis of vascular thrombosis. PMID- 9360875 TI - Long-term outcome of endoscopic balloon dilation in obstructive gastroduodenal Crohn's disease. AB - BACKGROUND AND STUDY AIMS: Although balloon dilation is widely used in nonmalignant pyloric stenosis, little information is available on either the short-term or long-term results of this type of therapy in patients with obstructive gastroduodenal Crohn's disease. PATIENTS AND METHODS: Five patients with Crohn's disease who had obstructive gastroduodenal lesions were treated using endoscopic balloon dilation. RESULTS: All the initial dilations successfully provided symptomatic relief. However, three of the five patients developed recurrent obstructive symptoms during a mean follow-up period of 4.2 years. Due to symptomatic recurrence, three patients required successive or regularly scheduled repeat balloon dilations, which were successful without any complications, and all of the patients were able to avoid surgical intervention. CONCLUSIONS: These results suggest that over a prolonged period of time, patients who have undergone balloon dilation for obstructive gastroduodenal Crohn's disease have a high rate of recurrence of symptomatic gastric obstruction. However, repeat dilations are successful in continuing to prevent the need for surgery. PMID- 9360876 TI - Symptom resolution or relief after cholecystectomy correlates strongly with positive combined endoscopic ultrasound and stimulated biliary drainage. AB - BACKGROUND AND STUDY AIMS: Combined endoscopic ultrasound and stimulated biliary drainage (EUS/SBD) has been shown to have better sensitivity than transabdominal ultrasonography (TUS) in the diagnosis of subtle gallbladder disease. The aim of the present study was to obtain long-term postoperative outcome data on a group of patients diagnosed by EUS/SBD. PATIENTS AND METHODS: Eighty-one patients underwent cholecystectomy for biliary pain after negative TUS findings (except for gallbladder sludge in three cases), but with positive EUS/SBD findings. EUS/SBD was performed as previously reported, with a positive result defined as gallbladder sludge or small stones noted on EUS or a positive biliary drainage. Clinical outcome data were obtained by phone an average of 15.4 months postoperatively. RESULTS: All 81 patients had a positive EUS/SBD, and all underwent cholecystectomy. Seventy-six of the patients (93.8%) had abnormal gallbladder histopathology. It was possible to contact 80 patients an average of 15.4 months postoperatively (range of 7-27 months). Seventy patients (87.5%) remained free of biliary pain, and in seven (8.8%) the symptoms had improved. CONCLUSION: When EUS/SBD results are positive, this correlates strongly with long term symptom resolution or relief (96.3%) after cholecystectomy. EUS/SBD demonstrated better sensitivity (93.8%) than TUS in diagnosing subtle gallbladder disease. PMID- 9360877 TI - Can noninvasive Helicobacter pylori testing save endoscopy? PMID- 9360878 TI - Endoscopies: too many and not enough! PMID- 9360879 TI - Which test for common bile duct stones? Endoscopic and intraductal ultrasonography. PMID- 9360880 TI - Which test for common bile duct stones? Magnetic resonance cholangiopancreatography. PMID- 9360881 TI - Which test for common bile duct stones? Endoscopic retrograde cholangiopancreatography. PMID- 9360882 TI - Clinical impact of routine biopsies of the gastric antrum and body. AB - Biopsy sampling of gastric mucosa at diagnostic endoscopy provides information that cannot be obtained by other means. The most common indication for gastric biopsy is the need to know whether or not the patient is infected with Helicobacter pylori, and whether the stomach is gastritic or not. Microscopic examination of gastric biopsy specimens, in addition to H. pylori status, provides information about the grade, extent, and topography of gastritis-related and atrophy-related lesions in the stomach. This information provides further opportunities for assessing the risk and likelihood of various gastric disorders. These are: a) The predominance or restriction of the H. pylori-related gastritis in the antrum strongly correlates with an increased risk of peptic ulcer disease, and of duodenal ulcer in particular (the duodenal ulcer phenotype of gastritis). b) The presence of atrophic gastritis (loss of normal glands) in the area of the gastric body indicates a low risk of ulcer and also a reduction in the capacity of the patient to secrete acid. c) The occurrence of advanced atrophic gastritis and intestinal metaplasia multifocally in the stomach (advanced multifocal atrophic gastritis), and in the lesser curvature and angular notch in particular, are features suggestive of an increased risk of gastric neoplasias (the gastric cancer phenotype of gastritis). d) The presence of normal and healthy gastric mucosa indicates, on the other hand, an extremely low risk of both peptic ulcer disease and gastric cancer. In addition to diagnosis of H. pylori-related gastritic lesions, routine gastric biopsies may reveal findings that indicate special forms of gastritis, such as eosinophilic, lymphocytic, reactive, or granulomatous gastritis (e.g., Crohn's gastritis), or Helicobacter heilmannii gastritis. These types of gastritis can be found incidentally in a small percentage of patients who undergo diagnostic gastroscopy for abdominal complaints. PMID- 9360883 TI - Laparoscopy-assisted endoscopic removal of a stromal-cell tumor of the stomach. AB - Endoscopic resection of gastrointestinal tumors is being performed with increased frequency. Submucosal mass lesions pose a particular problem, because of the risk of malignancy and the risk of complications associated with endoscopic removal. Increased incidences of both perforation and bleeding have been reported. We report here on a case in which we used a combined approach that included gastrointestinal endoscopy, laparoscopy, and laparoscopic ultrasound to resect a gastric leiomyoma. We consider that this approach enhanced our diagnostic capabilities, provided intraoperative options for resection, and enhanced the safety of the procedure. PMID- 9360884 TI - Coexistence of superficial esophageal carcinoma and leiomyoma: case report of an endoscopic resection. AB - A case of a 61 year old man who developed early esophageal cancer on top of a leiomyoma located in the upper third of the esophagus is described. Both lesions were successfully treated by endoscopic resection, without recurrence on short term-follow-up. PMID- 9360885 TI - Endoscopic snare papillectomy in patients with familial adenomatous polyposis and ampullary adenoma. AB - The optimal treatment of adenomas of the papilla of Vater has still not been definitively established, and the endoscopic excision of such lesions has received little attention in the literature. We report here the cases of two patients with familial adenomatous polyposis, in whom ampullary adenomas measuring 8 and 20 mm, respectively, were treated using one-piece snare excision of the lesion together with the papilla (snare papillectomy), followed by temporary biliopancreatic drainage. Procedure-related complications were an oozing-type hemorrhage and a mild pancreatitis, easily controlled by conservative measures. During the 18-month follow-up, one patient had a small recurrence that was successfully retreated. Further endoscopic and biopsy controls were negative. Although limited, our experience and the data in the literature indicate that snare papillectomy is a viable alternative to surgery for benign ampullary adenomas. Excising both the lesion and the papilla offers good oncological debridement and, unlike laser or thermal ablation, allows a complete histological evaluation of the pathological tissue. However, snare papillectomy should always be associated with temporary biliopancreatic drainage before or after the procedure in order to prevent ductal obstruction and serious pancreatitis. This maneuver should therefore preferably be performed by experienced endoscopists trained in therapeutic endoscopic retrograde cholangiopancreatography and hemostatic techniques. PMID- 9360886 TI - Arterial oxygen desaturation following sedated endoscopic examination. PMID- 9360887 TI - Esophageal Nikolsky's sign in pemphigus vulgaris. PMID- 9360888 TI - Acute graft-versus-host disease of the esophagus. PMID- 9360889 TI - Diffuse involvement of the gastrointestinal tract with MALT lymphoma. PMID- 9360890 TI - Laparoscopic removal of a benign tumor of the small bowel during gynecological surgery. PMID- 9360891 TI - Successful extracorporeal shock-wave lithotripsy for a single pancreatic stone located outside of an undilated main pancreatic duct. PMID- 9360892 TI - A case of simultaneous esophageal and pulmonary cancer treated by endoscopic mucosectomy and lobectomy using video-assisted minimal thoracotomy. PMID- 9360893 TI - Laparoscopic partial cystectomy for post-traumatic splenic pseudocyst. PMID- 9360894 TI - Color Doppler endosonography of esophageal varices: signal enhancement after intravenous injection of the ultrasound contrast agent Levovist. PMID- 9360895 TI - Two-port technique for laparoscopic cholecystectomy using a microendoscope. PMID- 9360896 TI - Endoscopic treatment for a gash in the esophagus caused when inserting the overtube during esophageal variceal ligation. PMID- 9360897 TI - Impact of the Human Genome Project on epidemiologic research. PMID- 9360898 TI - Evolving methods in genetic epidemiology. I. Analysis of genetic and environmental factors in family studies. PMID- 9360899 TI - Evolving methods in genetic epidemiology. II. Genetic linkage from an epidemiologic perspective. PMID- 9360900 TI - Evolving methods in genetic epidemiology. III. Gene-environment interaction in epidemiologic research. PMID- 9360901 TI - Evolving methods in genetic epidemiology. IV. Approaches to non-Mendelian inheritance. AB - From this overview it can be concluded that the understanding of the biologic properties and the development of analytic tools to identify repeat sequence mutations, genomic imprinting effects, and mitochondrial mutations are only beginning. Development of approaches to identify such phenomena as modifying effects or genetic components of complex traits is a new area of research. Not mentioned here are the ways in which locating a gene with such properties (i.e., linkage analysis) would be affected if such properties were not accounted for, or how to alter such analyses to obtain full information. Again, this is an exciting new area of research that will continue to motivate epidemiologists and geneticists. Hopefully, we have learned a lesson from the earlier conclusions of the studies on myotonic dystrophy: keep an open mind and never assume that the "geneticist should know best about behavior of genes". PMID- 9360902 TI - Population studies of allele frequencies in single gene disorders: methodological and policy considerations. PMID- 9360903 TI - Genetic epidemiology of birth defects: nonsyndromic cleft lip and neural tube defects. AB - This review has focused on only two common structural malformations. However, the difficulties and successes encountered while attempting to elucidate the genetic contribution to these two conditions are likely to be echoed in studies of other complex congenital anomalies. As our understanding of the mechanisms which give rise to a particular malformation gradually unfolds, the importance of a multidisciplinary approach to understanding the genetic contribution to these conditions becomes increasingly apparent. Experience indicates that both traditional and genetic epidemiologic approaches will be integral components of any such efforts, since the identification of environmental risk factors (e.g., folic acid) may provide clues regarding the nature of disease susceptibility loci, and the identification of susceptibility loci will provide new opportunities to explore potential environmental covariates of disease risk (e.g., maternal cigarette smoke). Although we are not yet in a position to completely describe the genetic contribution to any single structural malformation, advances over the past decade have led to a rapid increase in our ability to elucidate the relevant genetic factors. Given the complex nature of the nonsyndromic structural malformations, there is undoubtedly much work to be done before we fully understand the genetic contribution to even a single malformation. However, for the first time, such an understanding and the accompanying potential for prevention seem within our reach. PMID- 9360904 TI - Genetic epidemiology of breast and ovarian cancers. PMID- 9360905 TI - Genetic epidemiology of coronary artery disease. PMID- 9360906 TI - Molecular epidemiology of insulin-dependent diabetes mellitus. PMID- 9360907 TI - Genetic epidemiology of multiple sclerosis. AB - The continuing search for genetic loci which may influence multiple sclerosis susceptibility has probably been more complex and exciting than Spielman and Nathanson (4) could have imagined in 1982. Restriction fragment length polymorphisms no longer represent the "cutting edge" of technology. This entire area of research has gained incredible impetus with advances in molecular genetics and the advent of the "Human Genome Project." Readers must be cautioned that identification of a gene does not equate with a cure. Nevertheless, we are entering into a very exciting era with respect to the genetics and treatment of common complex disorders such as breast cancer, Alzheimer disease, and multiple sclerosis. Given the increasing awareness of the public about the role of genetics in the etiology of such disorders, a better understanding is needed of the legal, social, ethical, and psychologic implications of genetic research in multiple sclerosis. PMID- 9360908 TI - Genetic epidemiology of Alzheimer disease. PMID- 9360909 TI - Genetic epidemiology of epilepsy. PMID- 9360910 TI - Genetic epidemiology of asthma. PMID- 9360912 TI - DNA banking in epidemiologic studies. PMID- 9360911 TI - Genetic epidemiology of psychiatric disorders. PMID- 9360914 TI - Genetic epidemiology and the future of disease prevention and public health. PMID- 9360913 TI - Ethical and legal issues in genetic epidemiology. PMID- 9360915 TI - ECG abnormalities in myopathies, coronary heart disease and controls. AB - The aim of the study was to compare the prevalence of predefined ECG abnormalities, compiled from the literature, and of increased electrocardiographic myopathy indices (QT/PQs, P/PQs, R/S) among myopathy patients, patients with coronary heart disease and healthy subjects. ECGs from 27 myopathy patients, 35 patients with coronary heart disease and 36 healthy subjects were investigated. ECG abnormalities most often observed in myopathy patients were ST-abnormalities, T-wave abnormalities and tall R and/or S-waves. At least one increased electrocardiographic myopathy index was observed in 19% of the myopathy patients, 20% of the patients with coronary heart disease and 19% of the healthy subjects. At least one predefined ECG abnormality was found in 78% of the myopathy patients, 86% of the patients with coronary heart disease and 33% of the healthy subjects. In conclusion, ECG abnormalities frequently occur in myopathy patients and nearly as often as in patients with coronary heart disease. Electrocardiographic myopathy indices lack specificity and are thus of minor help in assessing myocardial alterations in myopathy patients. PMID- 9360920 TI - Warming early Mars with carbon dioxide clouds that scatter infrared radiation. AB - Geomorphic evidence that Mars was warm enough to support flowing water about 3.8 billion years ago presents a continuing enigma that cannot be explained by conventional greenhouse warming mechanisms. Model calculations show that the surface of early Mars could have been warmed through a scattering variant of the greenhouse effect, resulting from the ability of the carbon dioxide ice clouds to reflect the outgoing thermal radiation back to the surface. This process could also explain how Earth avoided an early irreversible glaciation and could extend the size of the habitable zone on extrasolar planets around stars. PMID- 9360925 TI - Regulation of distinct stages of skeletal muscle differentiation by mitogen activated protein kinases. AB - The signal transduction pathway or pathways linking extracellular signals to myogenesis are poorly defined. Upon mitogen withdrawal from C2C12 myoblasts, the mitogen-activated protein kinase (MAPK) p42Erk2 is inactivated concomitant with up-regulation of muscle-specific genes. Overexpression of MAPK phosphatase-1 (MKP 1) inhibited p42Erk2 activity and was sufficient to relieve the inhibitory effects of mitogens on muscle-specific gene expression. Later during myogenesis, endogenous expression of MKP-1 decreased. MKP-1 overexpression during differentiation prevented myotube formation despite appropriate expression of myosin heavy chain. This indicates that muscle-specific gene expression is necessary but not sufficient to commit differentiated myocytes to myotubes and suggests a function for the MAPKs during the early and late stages of skeletal muscle differentiation. PMID- 9360926 TI - Recovery of replication-competent HIV despite prolonged suppression of plasma viremia. AB - In evaluating current combination drug regimens for treatment of human immunodeficiency virus (HIV) disease, it is important to determine the existence of viral reservoirs. After depletion of CD8 cells from the peripheral blood mononuclear cells (PBMCs) of both patients and normal donors, activation of patient CD4 lymphocytes with immobilized antibodies to CD3 and CD28 enabled the isolation of virus from PBMCs of six patients despite the suppression of their plasma HIV RNA to fewer than 50 copies per milliliter for up to 2 years. Partial sequencing of HIV pol revealed no new drug resistance mutations or discernible evolution, providing evidence for viral latency rather than drug failure. PMID- 9360927 TI - Identification of a reservoir for HIV-1 in patients on highly active antiretroviral therapy. AB - The hypothesis that quiescent CD4+ T lymphocytes carrying proviral DNA provide a reservoir for human immunodeficiency virus-type 1 (HIV-1) in patients on highly active antiretroviral therapy (HAART) was examined. In a study of 22 patients successfully treated with HAART for up to 30 months, replication-competent virus was routinely recovered from resting CD4+ T lymphocytes. The frequency of resting CD4+ T cells harboring latent HIV-1 was low, 0.2 to 16.4 per 10(6) cells, and, in cross-sectional analysis, did not decrease with increasing time on therapy. The recovered viruses generally did not show mutations associated with resistance to the relevant antiretroviral drugs. This reservoir of nonevolving latent virus in resting CD4+ T cells should be considered in deciding whether to terminate treatment in patients who respond to HAART. PMID- 9360928 TI - Amidation of bioactive peptides: the structure of peptidylglycine alpha hydroxylating monooxygenase. AB - Many neuropeptides and peptide hormones require amidation at the carboxyl terminus for activity. Peptidylglycine alpha-amidating monooxygenase (PAM) catalyzes the amidation of these diverse physiological regulators. The amino terminal domain of the bifunctional PAM protein is a peptidylglycine alpha hydroxylating monooxygenase (PHM) with two coppers that cycle through cupric and cuprous oxidation states. The anomalous signal of the endogenous coppers was used to determine the structure of the catalytic core of oxidized rat PHM with and without bound peptide substrate. These structures strongly suggest that the PHM reaction proceeds via activation of substrate by a copper-bound oxygen species. The mechanistic and structural insight gained from the PHM structures can be directly extended to dopamine beta-monooxygenase. PMID- 9360929 TI - Requirement for the CD95 receptor-ligand pathway in c-Myc-induced apoptosis. AB - Induction of apoptosis by oncogenes like c-myc may be important in restraining the emergence of neoplasia. However, the mechanism by which c-myc induces apoptosis is unknown. CD95 (also termed Fas or APO-1) is a cell surface transmembrane receptor of the tumor necrosis factor receptor family that activates an intrinsic apoptotic suicide program in cells upon binding either its ligand CD95L or antibody. c-myc-induced apoptosis was shown to require interaction on the cell surface between CD95 and its ligand. c-Myc acts downstream of the CD95 receptor by sensitizing cells to the CD95 death signal. Moreover, IGF-I signaling and Bcl-2 suppress c-myc-induced apoptosis by also acting downstream of CD95. These findings link two apoptotic pathways previously thought to be independent and establish the dependency of Myc on CD95 signaling for its killing activity. PMID- 9360930 TI - A TEL-JAK2 fusion protein with constitutive kinase activity in human leukemia. AB - The Janus family of tyrosine kinases (JAK) plays an essential role in development and in coupling cytokine receptors to downstream intracellular signaling events. A t(9;12)(p24;p13) chromosomal translocation in a T cell childhood acute lymphoblastic leukemia patient was characterized and shown to fuse the 3' portion of JAK2 to the 5' region of TEL, a gene encoding a member of the ETS transcription factor family. The TEL-JAK2 fusion protein includes the catalytic domain of JAK2 and the TEL-specific oligomerization domain. TEL-induced oligomerization of TEL-JAK2 resulted in the constitutive activation of its tyrosine kinase activity and conferred cytokine-independent proliferation to the interleukin-3-dependent Ba/F3 hematopoietic cell line. PMID- 9360932 TI - Nonsyndromic deafness DFNA1 associated with mutation of a human homolog of the Drosophila gene diaphanous. AB - The gene responsible for autosomal dominant, fully penetrant, nonsyndromic sensorineural progressive hearing loss in a large Costa Rican kindred was previously localized to chromosome 5q31 and named DFNA1. Deafness in the family is associated with a protein-truncating mutation in a human homolog of the Drosophila gene diaphanous. The truncation is caused by a single nucleotide substitution in a splice donor, leading to a four-base pair insertion in messenger RNA and a frameshift. The diaphanous protein is a profilin ligand and target of Rho that regulates polymerization of actin, the major component of the cytoskeleton of hair cells of the inner ear. PMID- 9360934 TI - Bilateral vestibulopathy revisited. AB - Bilateral vestibular failure (BVF) is an often undetected disorder of the peripheral labyrinths or the eighth nerves. Key symptoms are oscillopsia during locomotion or head movements and unsteadiness, particularly in the dark. Diagnosis is made by a bedside test for defective vestibulo-ocular reflex and the absence of nystagmic reaction to both caloric and rotatory pendular testing. Most frequent etiologies include ototoxicity, cerebellar degeneration, meningitis, neuropathies, sequential vestibular neuritis, autoimmune disorders, tumors, and miscellaneous otological diseases. Idiopathic BVF is found in more than twenty percent of the patients. Recovery is possible but mostly incomplete. Somatosensory and visual input largely substitute the vestibular deficit for spatial orientation, postural balance and ocular motor control. PMID- 9360933 TI - daf-16: An HNF-3/forkhead family member that can function to double the life-span of Caenorhabditis elegans. AB - The wild-type Caenorhabditis elegans nematode ages rapidly, undergoing development, senescence, and death in less than 3 weeks. In contrast, mutants with reduced activity of the gene daf-2, a homolog of the insulin and insulin like growth factor receptors, age more slowly than normal and live more than twice as long. These mutants are active and fully fertile and have normal metabolic rates. The life-span extension caused by daf-2 mutations requires the activity of the gene daf-16. daf-16 appears to play a unique role in life-span regulation and encodes a member of the hepatocyte nuclear factor 3 (HNF 3)/forkhead family of transcriptional regulators. In humans, insulin down regulates the expression of certain genes by antagonizing the activity of HNF-3, raising the possibility that aspects of this regulatory system have been conserved. PMID- 9360935 TI - Salai Guggal - Boswellia serrata: from a herbal medicine to a non-redox inhibitor of leukotriene biosynthesis. PMID- 9360936 TI - Identification of characteristics for malignancy of solitary pulmonary nodules using high-resolution computed tomography. AB - The aim of this prospective study was to apply the described single pathological appearance and possibilities of differentiating signs from other studies and summarize them concerning their differential diagnostic importance to improve differential diagnostic strategies concerning the dignity of solitary pulmonary nodules. 55 consecutive patients with solitary pulmonary nodules were examinated using high-resolution computed tomography (HRCT) before surgery. Thereafter HRCT diagnosis was proven by histological assessment. Only lesions which were removed by surgery were used. No lesion was excluded by size. Necrotic areas, cavitation, satellite lesions and circumscribed pleural thickening were only found in the malignant nodules. Discrimination between benign and malignant lesions was possible by: mean diameter (P<.01), mean density (P<.01) and air inclusion (P<.05), by air bronchogram/bronchiologram (P<.05), indistinct/fogged (P<.05) and dystelectatic (P<.01) margin, the presence (P<.01) and length (P<.01) of spiculae, spiculae extended into the pleura visceralis (P<.05) and pleural distension (P<.01). A single sign can be seen in either benign or malignant nodules, but if considered together with other signs it may have a different meaning. HRCT can enable a differentiation of BSPN from MSPN in the majority of cases. As imaging methods could not get a nearly complete certainty about the dignity the chance of survival of patients could be preserved exclusively by an early surgery. PMID- 9360937 TI - Differential presentation of cortical and trabecular peripheral bone mineral density in acromegaly. AB - Growth hormone (GH) has been suggested as a therapeutic tool for the treatment of osteopenia. To assess the differential influence of growth hormone on cortical and trabecular bone, bone mineral densities (BMD) of the ultradistal radius were determined in 18 men and 19 women with clinically and biochemically confirmed acromegaly using peripheral computed tomography and a specialized scanner (Stratec XCT 900). The results were expressed in equivalents to hydroxyl-apatite (mg/ccm) and compared with the BMD of healthy controls (17 men, 34 women). Cortical bone mineral density was significantly higher in acromegalic women (295.2 +/- 18.4, X +/- SEM) and men (339.4 +/- 21.2) compared to healthy women (243.0 +/- 12.8) and men (272.2 +/- 15.9). In contrast, trabecular BMD did not differ between acromegalic patients (men: 161.0 +/- 16.1; women: 116.5 +/- 10.5) and controls (men: 158.0 +/- 12.2; women: 134.1 +/- 6.3). Acromegalic women showed a significant correlation between insulin-like growth factor (IGF-I) expression and cortical BMD, whereas in acromegalic men GH levels correlated significantly with cortical BMD. Greatly increased serum osteocalcin levels in both, acromegalic men (15.5 +/- 3.3 ng/ml) and women (12.9 +/- 1.8) compared to controls (men: 6.7 +/- 1.7; women: 7.7 +/- 1.0) indicates the activation of osteoblastic bone formation. This study revealed an increase in cortical BMD at the forearm; in acromegalic patients; though trabecular BMD did not differ from controls. The differential mineralization of cortical and trabecular bone in acromegaly may be indicative of the detrimental effect accompanying pituitary insufficiency can have on trabecular bone, despite substitution therapy, but could also be due to different reactivity of cortical and trabecular bone to GH and/or IGF I. The observable increase of bone mineral density in acromegaly suggests a potential use for GH in treating osteoporosis. PMID- 9360938 TI - Familial hypercholesterolemia and familial defective apolipoprotein B-100: comparison of the phenotypic expression In 116 cases. AB - Familial hypercholesterolemia (FH) is characterized by an increased level of LDL cholesterol, tendon xanthomas and an elevated risk of premature coronary artery disease (CAD). FH is caused by different mutations in the low density lipoprotein receptor (LDLR) gene or by a G to A mutation in exon 26 of the apolipoprotein B gene causing familial defective apolipoprotein B-100 (FDB). To compare the phenotypic expression of either defect, we studied 83 patients (76 heterozygous and 7 homozygous persons) with LDLR defects and 33 heterozygous FDB patients from Germany. We took into account other risk factors for CAD. In contrast to earlier studies, our patients where prospectively ascertained from the lipid clinic and tested for the G-A mutation. The average total cholesterol level in plasma was 413.7 mg/dl in LDLR patients and 321.8 mg/dl in FDB patients. Patients with LDLR defects had a significantly higher risk of myocardial infarction, coronary artery bypass graft, positive coronary angiography, atherosclerotic plaques in the carotid arteries and CAD (p<0.01) than patients with FDB. CAD was present in 33% and plaques in the carotid arteries in 82% of the patients with LDLR defects. No patient with FDB had severe CAD, while only 52% had plaques in the carotid arteries (p<0.05). Thus in our study, hypercholesterolemia and premature atherosclerosis were more common in LDLR patients than in FDB patients. We believe that the striking difference in CHD incidence is not sufficiently explained by the higher LDL levels in LDLR patients. A possible explanation may be that in LDLR patients, the metabolism of low density lipoproteins, intermediate density lipoproteins and very low density lipoproteins is disrupted, whereas in FDB patients there is only disruption in apo B-containing LDL. PMID- 9360939 TI - The efficacy of an oral immunostimulant in treating periodontitis - a pilot study. AB - The effect of an oral immunostimulant on adult periodontitis was evaluated in a pilot study. The preparation is successfully administered in respiratory tract infections but has not been used in oral medicine. 11 patients were treated with a bacterial lysate for three months after completing a hygiene phase preceding the study protocol. At day 0 and after 30, 60, and 90 days of medication, parameters characterizing disease activity (bleeding on probing, probing depth, clinical attachment loss and suppuration) and oral hygiene (plaqueindex) were recorded and compared to 10 controls. The treatment resulted in reduced gingival inflammatory activity and diminishing probing depths which was significant compared to the controls (p < 0.001). The exact mechanism of action induced by immunostimulant therapy remains to be clarified. The promising results of this pilot study offer a new aspect in the therapy of periodontal disease. Further investigations are necessary to define the therapeutic value of this treatment in oral medicine. PMID- 9360941 TI - Conservative therapy in an ERCP-induced abdominal abscess. AB - We describe a 30 year-old man who presented with an abdominal abscess as an unusual complication of endoscopic retrograde cholangiopancreatography with papillotomy. His presenting symptom was recurrent vomiting, while fever, abdominal pain, and leukocytosis were not significant. The abscess was observed with repeated computerized tomographic scans and completely regressed with intravenous antibiotic treatment over a three week period, leading to complete remission. PMID- 9360940 TI - Serological IgG, IgM and IgA diagnosis and prognosis of mycobacterial diseases in routine practice. AB - The routine diagnosis of tuberculosis and other mycobacterial diseases based on organism identification was completed during a period of one year in 730 patients, with serological IgG, IgM and IgA determination of antibodies against antigen 60 from M. bovis , strain BCG. The analysis was performed on 10 groups of patients consisting of 1) inflammatory diseases of the respiratory tract, 2) pericarditis, myocarditis, lymphadenitis and CNS diseases, 3) chronic non inflammatory diseases of kidneys, liver and pancreas, 4) non-inflammatory diseases of the heart, sarcoidosis and pneumoconiosis, 5) tumor, 6) healthy people with TB contact, 7) inactive TB, 8) culture-positive pulmonary and extra pulmonary TB, 9) culture-negative TB and extra-pulmonary TB, and 10) potentially pathogenic mycobacteria. The specificity of the test (100% negative cases in Group 6, composed of healthy people) is estimated at about 90%, in accordance with determinations made in other laboratories. In non-tuberculous patients, the specificity varied according to the analysed groups. Group 1 was largely unspecific for IgM (76% positives) but the specificity was acceptable for IgG (6.2% positives ) and IgA (7.4% positives). Group 2 was similar to Group 1. Group 3 was associated with positive IgA titers. Group 4 was only exceptiony seropositive and Group 5 was positive mainly for IgA (11. 4%) associated with lower respiratory tract ailments. This unspecific seropositivity was attributed to inapparent infections by PPM whose colonisation was favored by the particular disease of the patients. The sensitivity of serological measurements applied to the diagnosis of TB patients and PPM patients was similar, regardless if the disease was pulmonary or non-pulmonary, regardless if cultures were positive or not and, in our hands, was low (positivity for IgA about 30 %, for IgM about 10% and for IgG about 30%). This poor sensitivity observed with people presenting for treatment is attributed to an immune depression occuring mainly in elderly patients. The remarkable sensitivity of the serological instrument applied to culture-negative pulmonary and non-pulmonary TB cases as well as PPM cases makes the test a good adjuvant in cases of suspicion of TB. The assessment of the serological status of people under chemotherapy is worth the analysis, a high IgG level being associated with immunocompetence while the absence of IgG antibodies and/or the presence of IgA antibodies denotes an immunologically misdirected response potentially opening the way to chronic infections. PMID- 9360942 TI - The mechanism of Ca2+ transport by sarco(endo)plasmic reticulum Ca2+-ATPases. PMID- 9360944 TI - Angiostatin-converting enzyme activities of human matrilysin (MMP-7) and gelatinase B/type IV collagenase (MMP-9). AB - Angiostatin is one of the most potent inhibitors of angiogenesis. Reports have shown that metalloelastase, pancreas elastase, plasmin reductase, and plasmin convert plasminogen to angiostatin. However, the cleavage sites of plasminogen by those enzymes have not been determined. Here we demonstrate that two members of the human matrix metalloproteinase (MMP) family, matrilysin (MMP-7) and gelatinase B/type IV collagenase (MMP-9), hydrolyze human plasminogen to generate angiostatin fragments. The cleavage sites have been determined. The 58-kDa bands derived from plasminogen by MMP-7 and MMP-9 both have the N-terminal sequence KVYLSEXKTG, which corresponds to that of angiostatin. This N terminus is identical to that of the starting plasminogen itself and corresponds to residues 97-106 of prepro-plasminogen. The 42- and 38-kDa bands generated by MMP-7 both have the N-terminal sequence VVLLPNVETP, which corresponds to the amino acid sequence 467-476 of prepro-plasminogen, between kringle domain 4 and 5. MMP-9 cleaves plasminogen to generate a 42-kDa fragment with the N-terminal sequence PVVLLPNVE, 1 residue upstream of the MMP-7 cleavage site. These results indicate that MMP-7 and MMP-9 may regulate new blood vessel formation by cleaving plasminogen and generating angiostatin molecules. PMID- 9360943 TI - The acid-sensitive ionic channel subunit ASIC and the mammalian degenerin MDEG form a heteromultimeric H+-gated Na+ channel with novel properties. AB - Proton-gated cation channels are acid sensors that are present in both sensory neurons and in neurons of the central nervous system. One of these acid-sensing ion channels (ASIC) has been recently cloned. This paper shows that ASIC and the mammalian degenerin MDEG, which are colocalized in the same brain regions, can directly associate with each other. Immunoprecipitation of MDEG causes coprecipitation of ASIC. Moreover, coexpression of ASIC and MDEG subunits in Xenopus oocytes generates an amiloride-sensitive H+-gated Na+ channel with novel properties (different kinetics, ionic selectivity, and pH sensitivity). In addition, coexpression of MDEG with mutants of the ASIC subunit can create constitutively active channels that become completely nonselective for Na+ versus K+ and H+-gated channels that have a drastically altered pH sensitivity compared with MDEG. These data clearly show that ASIC and MDEG can form heteromultimeric assemblies with novel properties. Heteromultimeric assembly is probably used for creating a diversity of H+-gated cation channels acting as neuronal acid sensors in different pH ranges. PMID- 9360945 TI - Transcription factor NF-kappaB regulates inducible Oct-2 gene expression in precursor B lymphocytes. AB - The POU transcription factors Oct-1 and Oct-2 regulate the activity of octamer dependent promoters, including those that direct transcription from rearranged immunoglobulin genes. Unlike Oct-1, which is constitutively expressed in many cell types, Oct-2 expression is restricted primarily to B lymphocytes and can be induced in precursor B cells by stimulation with bacterial lipopolysaccharide (LPS). However, the precise factors that mediate this induction mechanism remain unknown. In the present study, we monitored Oct-2 expression in cells arrested for the activation of NF-kappaB, an LPS-responsive member of the Rel transcription factor family. Despite stimulation with LPS, disruption of the NF kappaB signaling pathway in precursor B cells led to the loss of inducible Oct-2 DNA binding activity in vitro and the suppression of Oct-2-directed transcription in vivo. This biochemical defect correlated with a specific block to Oct-2 gene expression at the level of transcription, whereas the expression of Oct-1 was unaffected. The finding that Oct-2 is under NF-kappaB control highlights an important cross-talk mechanism involving two distinct transcription factor families that regulate B lymphocyte function. PMID- 9360946 TI - Ras-dependent signaling by the GTPase-deficient mutant of Galpha12. AB - Galpha12 and Galpha13 regulate diverse responses through the small GTPases Ras, CDC42, Rac, and Rho. Whereas they activate similar responses in many different cell types, they also activate more specific and critical signaling pathways in other cell types. In COS cells, in which both Galpha12 and Galpha13 stimulate Na+/H+ exchange, they do so by activating different signaling pathways. Here we report that the differential recruitment of specific small GTPases by Galpha12 and Galpha13 defines the molecular basis for their functional differences. We have observed that the stimulation of Na+/H+ exchange by the GTPase-deficient mutant of Galpha12 (Galpha12QL) requires a functional Ras and is independent of Rac/CDC42 and Jun kinase signaling module. By contrast, the stimulation of Na+/H+ exchange by Galpha13QL requires a functional Rac/CDC42 and the Jun kinase signaling module. Our results also indicate that Galpha12QL-Ras stimulation of Na+/H+ exchange involves a D609-sensitive phospholipase and protein kinase C. These studies, for the first time, describe a novel Galpha12-specific signaling pathway involving Ras, phosphatidylcholine hydrolysis, and protein kinase C in the regulation of Na+/H+ exchange. PMID- 9360947 TI - Insertion mutagenesis as a tool in the modification of protein function. Extended substrate specificity conferred by pentapeptide insertions in the omega-loop of TEM-1 beta-lactamase. AB - The TEM-1 beta-lactamase enzyme efficiently hydrolyzes beta-lactam antibiotics such as ampicillin but cleaves third generation cephalosporin antibiotics poorly. Variant beta-lactamases that conferred elevated levels of resistance to the cephalosporin ceftazidime were identified in a set of beta-lactamase derivatives previously generated by pentapeptide scanning mutagenesis in which a variable 5 amino acid cassette was introduced randomly in the target protein. This mutagenesis procedure was also modified to allow the direct selection of variant beta-lactamases with pentapeptide insertions that conferred extended substrate specificities. All insertions associated with enhanced resistance to ceftazidime were targetted to the 19-amino acid Omega-loop region, which forms part of the catalytic pocket of the beta-lactamase enzyme. However, pentapeptide insertions in the C- and N-terminal halves of this region had different effects on the ability of the enzyme to hydrolyze ampicillin in vivo. Larger insertions that increased the length of the Omega-loop by up to 2-fold also retained catalytic activity toward ampicillin and/or ceftazidime in vivo. In accord with previous substitution mutation studies, these results emphasize the extreme flexibility of the Omega-loop with regards the primary structure requirements for ceftazidime hydrolysis by beta-lactamase. The potential of pentapeptide scanning mutagenesis in mimicking evolution events that result from the insertion and excision of transposons in nature is discussed. PMID- 9360948 TI - Gly-Pro-Arg confers stability similar to Gly-Pro-Hyp in the collagen triple-helix of host-guest peptides. AB - A set of host-guest peptides of the form Ac(Gly-Pro-Hyp)3-Gly-X-Y-(Gly-Pro-Hyp)4 Gly-Gly-NH2 has been designed to evaluate the propensity of different Gly-X-Y triplets for the triple-helix conformation (Shah, N. K., Ramshaw, J. A. M., Kirkpatrick, A., Shah, C., and Brodsky, B. (1996) Biochemistry 35, 10262-10268). All Gly-X-Y guest triplets led to a decrease in melting temperature from the host (Gly-Pro-Hyp)8 peptide except for Gly-Pro-Arg. In this Gly-Pro-Hyp-rich environment, Gly-Pro-Arg was found to be as stabilizing as Gly-Pro-Hyp. Decreased stability of host-guest peptides containing Gly-Pro-Lys, Gly-Pro-homo-Arg, and Gly-Arg-Hyp compared with Gly-Pro-Arg indicated a stabilization that is optimal for Arg and specific to the Y-position. Arg was found to have a similar stabilizing effect when residues other than Pro are in the X-position. Both Arg and Hyp stabilize the triple-helix preferentially in the Y-position in a stereospecific manner and occupy largely Y-positions in collagen. However, contiguous Gly-Pro-Hyp units are highly stable and promote triple-helix folding, whereas incorporation of multiple Gly-Pro-Arg triplets was destabilizing and folded slowly due to charge repulsion. In collagen, Gly-Pro-Arg may contribute maximally to local triple-helix stability while also having the potential for electrostatic interactions in fibril formation and binding. PMID- 9360949 TI - Characterization of the native lysine tyrosylquinone cofactor in lysyl oxidase by Raman spectroscopy. AB - Lysine tyrosylquinone (LTQ) recently has been identified as the active site cofactor in lysyl oxidase by isolation and characterization of a derivatized active site peptide. Reported in this study is the first characterization of the underivatized cofactor in native lysyl oxidase by resonance Raman (RR) spectrometry. The spectrum is characterized by a unique set of vibrational modes in the 1200 to 1700 cm-1 region. We show that the RR spectrum of lysyl oxidase closely matches that of a synthetic LTQ model compound, 4-n-butylamino-5-ethyl 1,2-benzoquinone, in aqueous solutions but differs significantly from those of other topa quinone-containing amine oxidases under similar conditions. Furthermore, we have observed the same 18O shift of the C=O stretch in both the lysyl oxidase enzyme and the LTQ cofactor model compound. The RR spectra of different model compounds and their D shifts give additional evidence for the protonation state of LTQ cofactor in the enzyme. The overall similarity of these spectra and their shifts shows that the lysyl oxidase cofactor and the model LTQ compound have the same structure and properties. These data provide strong and independent support for the new cofactor structure, unambiguously ruling out the possibility that the structure originally reported had been derived from a spurious side reaction during the derivatization of the protein and isolation of the active site peptide. PMID- 9360950 TI - Molecular determinants of substrate selectivity in Na+-dependent nucleoside transporters. AB - In mammalian cells, the salvage of purine and pyrimidine nucleosides is mediated by both facilitated and Na+-dependent nucleoside transporters. These transporters also play important roles in the transmembrane flux of therapeutic nucleoside analogs, which are widely used in the treatment of cancer and viral infections. The N1, N2, and N3 Na+-dependent nucleoside transporters differ in terms of their transport selectivity for purine and pyrimidine nucleosides. N1 is purine selective, N2 is pyrimidine-selective, and N3 is broadly selective. To identify structural domains involved in substrate binding and molecular determinants responsible for distinct transport selectivity, chimeric transporters were made from the cloned rat N1 and N2 transporters. Of the 14 transmembrane domains (TM) of N1 and N2, transplanting TM8-9 of N1 into N2 converted N2 from a pyrimidine- to a purine-selective transporter. Transplanting only TM8 generated a chimera with characteristics similar to the N3 transporter that has yet to be cloned. These data suggest that TM8-9 confer substrate selectivity and may form at least part of a substrate-binding site in Na+-dependent nucleoside transporters. PMID- 9360951 TI - Agonist-receptor-arrestin, an alternative ternary complex with high agonist affinity. AB - The rapid decrease of a response to a persistent stimulus, often termed desensitization, is a widespread biological phenomenon. Signal transduction by numerous G protein-coupled receptors appears to be terminated by a strikingly uniform two-step mechanism, most extensively characterized for the beta2 adrenergic receptor (beta2AR), m2 muscarinic cholinergic receptor (m2 mAChR), and rhodopsin. The model predicts that activated receptor is initially phosphorylated and then tightly binds an arrestin protein that effectively blocks further G protein interaction. Here we report that complexes of beta2AR-arrestin and m2 mAChR-arrestin have a higher affinity for agonists (but not antagonists) than do receptors not complexed with arrestin. The percentage of phosphorylated beta2AR in this high affinity state in the presence of full agonists varied with different arrestins and was enhanced by selective mutations in arrestins. The percentage of high affinity sites also was proportional to the intrinsic activity of an agonist, and the coefficient of proportionality varies for different arrestin proteins. Certain mutant arrestins can form these high affinity complexes with unphosphorylated receptors. Mutations that enhance formation of the agonist-receptor-arrestin complexes should provide useful tools for manipulating both the efficiency of signaling and rate and specificity of receptor internalization. PMID- 9360952 TI - Mouse brain microglia express interleukin-15 and its multimeric receptor complex functionally coupled to Janus kinase activity. AB - The cytokine, interleukin (IL)-15, and the T cell growth factor, IL-2, exhibit a similar spectrum of immune effects and share the IL-2 receptor (IL-2R) subunits IL-2Rbeta and IL-2Rgamma for signaling in hematopoietic cells. Numerous neuroregulatory activities of IL-2 have been suggested, but its expression in the normal central nervous system (CNS) is apparently very low and regionally restricted. We show by RNA and protein detection that IL-15, its specific receptor molecule, IL-15Ralpha, and the signal-transducing receptor subunits, IL 2Rbeta and IL-2Rgamma, are constitutively present in various regions of the developing and adult mouse brain. We further demonstrate, also at the single-cell level, that IL-15 and the components for IL-15Ralpha/IL-2Rbetagamma receptors are expressed by microglia. Tyrosine phosphorylation data are presented showing that IL-15 signaling in microglia involves Janus kinase 1 activity. At doses of 0.1-10 ng/ml, IL-15 affected functional properties of these cells, such as the production of nitric oxide, and supported their growth in culture, suggestive of a role as an autocrine growth factor. Microglial IL-15 could thus play a pivotal role in the CNS and may participate in certain CNS and neuroendocrine functions previously ascribed to IL-2. PMID- 9360953 TI - Residues in the membrane-spanning and extracellular loop regions of the parathyroid hormone (PTH)-2 receptor determine signaling selectivity for PTH and PTH-related peptide. AB - The parathyroid hormone (PTH)-2 receptor displays strong ligand selectivity in that it responds fully to PTH but not at all to PTH-related peptide (PTHrP). In contrast, the PTH-1 receptor (PTH/PTHrP receptor) responds fully to both ligands. Previously it was shown that two divergent residues in PTH and PTHrP account for PTH-2 receptor selectivity; position 23 (Trp in PTH and Phe in PTHrP) determines binding selectivity and position 5 (Ile in PTH and His in PTHrP) determines signaling selectivity. To identify sites in the PTH-2 receptor involved in discriminating between His5 and Ile5, we constructed PTH-2 receptor/PTH-1 receptor chimeras, expressed them in COS-7 cells, and tested for cAMP responsiveness to [Trp23] PTHrP-(1-36), and to the nondiscriminating peptide [Ile5, Trp23]PTHrP-(1-36) (the Phe23 --> Trp modification enabled high affinity binding of each ligand to the PTH-2 receptor). The chimeras revealed that the membrane-spanning/loop region of the receptor determined His5/Ile5 signaling selectivity. Subsequent analysis of smaller cassette substitutions and then individual point mutations led to the identification of two single residues that function as major determinants of residue 5 signaling selectivity. These residues, Ile244 at the extracellular end of transmembrane helix 3, and Tyr318 at the COOH-terminal portion of extracellular loop 2, are replaced by Leu and Ile in the PTH-1 receptor, respectively. The results thus indicate a functional interaction between two residues in the core region of the PTH-2 receptor and residue 5 of the ligand. PMID- 9360954 TI - Mu opioid receptor phosphorylation, desensitization, and ligand efficacy. AB - Mu opioid receptors are subject to phosphorylation and desensitization through actions of at least two distinct biochemical pathways: agonist-dependent mu receptor phosphorylation and desensitization induced by a biochemically distinct second pathway dependent on protein kinase C activation (1). To better understand the nature of the agonist-induced mu receptor phosphorylation events, we have investigated the effects of a variety of opiate ligands of varying potencies and intrinsic activities on mu receptor phosphorylation and desensitization. Exposure to the potent full agonists sufentanil, dihydroetorphine, etorphine, etonitazine, and [D-Ala2, MePhe4, Glyol5]enkephalin (DAMGO) led to strong receptor phosphorylation, while methadone, l-alpha-acetylmethadone (LAAM), morphine, meperidine, DADL, beta-endorphin(1-31), enkephalins, and dynorphin A(1-17) produced intermediate effects. The partial agonist buprenorphine minimally enhanced receptor phosphorylation while antagonists failed to alter phosphorylation. Buprenorphine and full antagonists each antagonized the enhanced mu receptor phosphorylation induced by morphine or DAMGO. The rank order of opiate ligand efficacies in producing mu receptor-mediated functional desensitization generally paralleled their rank order of efficacies in producing receptor phosphorylation. Interestingly, the desensitization and phosphorylation mediated by methadone and LAAM were disproportionate to their efficacies in two distinct test systems. This generally good fit between the efficacies of opiates in mu receptor activation, phosphorylation, and desensitization supports the idea that activated receptor/agonist/G-protein complexes and/or receptor conformational changes induced by agonists are required for agonist-induced mu receptor phosphorylation. Data for methadone and LAAM suggest possible contribution from their enhanced desensitizing abilities to their therapeutic efficacies. PMID- 9360955 TI - Zinc inhibition of mitochondrial aconitase and its importance in citrate metabolism of prostate epithelial cells. AB - Prostate epithelial cells possess a uniquely limiting mitochondrial (m-) aconitase activity that minimizes their ability to oxidize citrate. These cells also possess uniquely high cellular and mitochondrial zinc levels. Correlations among zinc, citrate, and m-aconitase in prostate indicated that zinc might be an inhibitor of prostate m-aconitase activity and citrate oxidation. The present studies reveal that zinc at near physiological levels inhibited m-aconitase activity of mitochondrial sonicate preparations obtained from rat ventral prostate epithelial cells. Corresponding studies conducted with mitochondrial sonicates of rat kidney cells revealed that zinc also inhibited the kidney m aconitase activity. However the inhibitory effect of zinc was more sensitive with the prostate m-aconitase activity. Zinc inhibition fit the competitive inhibitor model. The inhibitory effect of zinc occurred only with citrate as substrate and was specific for the citrate --> cis-aconitate reaction. Other cations (Ca2+, Mn2+, Cd2+) did not result in the inhibitory effects obtained with zinc. The presence of endogenous zinc inhibited the m-aconitase activity of the prostate mitochondrial preparations. Kidney preparations that contain lower endogenous zinc levels exhibited no endogenous inhibition of m-aconitase activity. Studies with pig prostate and seminal vesicle mitochondrial preparations also revealed that zinc was a competitive inhibitor against citrate of m-aconitase activity. The effects of zinc on purified beef heart m-aconitase verified the competitive inhibitor action of zinc. In contrast, zinc had no inhibitory effect on purified cytosolic aconitase. These studies reveal for the first time that zinc is a specific inhibitor of m-aconitase of mammalian cells. In prostate epithelial cells, in situ mitochondrial zinc levels inhibit m-aconitase activity, which provides a mechanism by which citrate oxidation is limited. PMID- 9360956 TI - 14-3-3 is phosphorylated by casein kinase I on residue 233. Phosphorylation at this site in vivo regulates Raf/14-3-3 interaction. AB - 14-3-3 proteins mediate interactions between proteins involved in signal transduction and cell cycle regulation. Phosphorylation of target proteins as well as 14-3-3 are important for protein-protein interactions. Here, we describe the purification of a protein kinase from porcine brain that phosphorylates 14-3 3 zeta on Thr-233. This protein kinase has been identified as casein kinase Ialpha (CKIalpha) by peptide mapping analysis and sequencing. Among mammalian 14 3-3, only 14-3-3 tau possesses a phosphorylatable residue at the same position (Ser-233), and we show that this residue is also phosphorylated by CKI. In addition, we show that 14-3-3 zeta is exclusively phosphorylated on Thr-233 in human embryonic kidney 293 cells. The residue 233 is located within a region shown to be important for the association of 14-3-3 to target proteins. We showed previously that, in 293 cells, only the unphosphorylated form of 14-3-3 zeta associates with the regulatory domain of c-Raf. We have now shown that in vivo phosphorylation of 14-3-3 zeta at the CKIalpha site (Thr-233) negatively regulates its binding to c-Raf, and may be important in Raf-mediated signal transduction. PMID- 9360957 TI - Requirement of cysteine-rich repeats of the Fas receptor for binding by the Fas ligand. AB - The Fas receptor is a member of a family of cell death receptors, including tumor necrosis factor receptor I (TNFR I), death receptor 3 and 4 (DR3 and DR4), and cytopathic avian receptor 1 (CAR1). The Fas receptor is composed of several discrete domains, including three cysteine-rich domains (CRDs), a transmembrane domain, and an intracellular domain responsible for transmitting an apoptotic signal. While the mechanism of Fas-mediated cell death has become elucidated, the requirements for Fas ligand binding to the receptor have not been fully defined. Using a series of chimeric Fc-receptor fusion proteins between the human Fas receptor and TNFR I, each cysteine-rich domain of Fas was found to be required for interaction with the Fas ligand. Interestingly, TNFR I CRD1 could partially substitute for the Fas CRD1. The importance of this domain was underscored by the analysis of a Fas extracellular mutation (C66R), which resulted in a complete loss of ligand binding. This mutation was cloned from a human patient suffering from Canale-Smith syndrome, which is characterized by autoimmunity resembling that observed in the lpr and lprcg mice. The localization of essential ligand binding domains in the Fas receptor correlated exactly with the ability of the Fas receptor fusion proteins to prevent cell death mediated by the Fas ligand. PMID- 9360958 TI - Characterization of a novel gut-specific chitinase gene from the human malaria vector Anopheles gambiae. AB - Chitinases that function in the molting of the larval exoskeleton have been characterized previously. However, chitinase expression in an adult insect gut has not been described. Here we report on the initial characterization and cloning of a novel chitinase gene that is expressed specifically in the midgut of adult Anopheles gambiae females. Upon feeding, chitinase is secreted into the gut lumen as an inactive pro-enzyme that is later activated by trypsin. Thus, temporal regulation of chitinase activity is tightly coupled to the temporal pattern of trypsin secretion. The enzyme may play a role in structuring the chitin-containing extracellular peritrophic matrix, whose formation is also induced by feeding. A chitinase cDNA was cloned from a library enriched for gut specific sequences. The open reading frame encodes a 525-amino acid protein comprised of a putative catalytic domain at the N terminus, a putative chitin binding domain at the C terminus, and a threonine/serine/proline-rich amino acid stretch in between them. Northern analysis indicates that this chitinase is expressed exclusively in the guts of adult females and not in adult carcasses or in any larval or pupal tissues. The present findings suggest the possibility of using this chitinase as an antigen for a malaria transmission-blocking vaccine. PMID- 9360959 TI - A cytosolic sperm protein factor mobilizes Ca2+ from intracellular stores by activating multiple Ca2+ release mechanisms independently of low molecular weight messengers. AB - Ca2+ oscillations can be induced in mammalian eggs and somatic cells by microinjection of a cytosolic sperm protein factor. The nature of the sperm factor-induced Ca2+ signaling was investigated by adding sperm protein extracts to homogenates of sea urchin eggs, which contain multiple classes of Ca2+ release mechanisms. We show that the sperm factor mobilizes Ca2+ from non-mitochondrial Ca2+ stores in egg homogenates after a distinct latency. This latency is abolished by preincubation of sperm extracts with egg cytosol. The preincubation step is highly temperature-dependent and generates a high molecular weight, protein-based Ca2+-releasing agent that can also mobilize Ca2+ from purified egg microsomes. This Ca2+ release appears to be mediated via both inositol 1,4,5 trisphosphate and ryanodine receptors, since homologous desensitization of these two release mechanisms by their respective agonists inhibits further release by the sperm factor. However, sperm factor-induced Ca2+ release by these channels is independent of inositol 1,4, 5-trisphosphate or cADPR since antagonists of either of these two messengers did not block the Ca2+ release effected by the sperm factor. The sperm protein factor may cause Ca2+ release via an enzymatic step that generates a protein-based Ca2+-releasing agent. PMID- 9360960 TI - Anti-mutagenic activity of DNA damage-binding proteins mediated by direct inhibition of translesion replication. AB - DNA lesions that block replication can be bypassed in Escherichia coli by a special DNA synthesis process termed translesion replication. This process is mutagenic due to the miscoding nature of the DNA lesions. We report that the repair enzyme formamido-pyrimidine DNA glycosylase and the general DNA damage recognition protein UvrA each inhibit specifically translesion replication through an abasic site analog by purified DNA polymerases I and II, and DNA polymerase III (alpha subunit) from E. coli. In vivo experiments suggest that a similar inhibitory mechanism prevents at least 70% of the mutations caused by ultraviolet light DNA lesions in E. coli. These results suggest that DNA damage binding proteins regulate mutagenesis by a novel mechanism that involves direct inhibition of translesion replication. This mechanism provides anti-mutagenic defense against DNA lesions that have escaped DNA repair. PMID- 9360961 TI - Termination of quiescence in crustacea. The role of transfer RNA aminoacylation in the brine shrimp Artemia. AB - In quiescent embryos of the brine shrimp Artemia, the level of aminoacylation of transfer RNAs is low. During resumption of development the charging level of transfer RNAs increases, concomitant with the activation of protein synthesis. The total level of charging rises dramatically from an average of 4% to 50% within a period of 24 h of development. The restriction of in vitro translation of the quiescent embryo extract can be partially released by the addition of charged aminoacyl-tRNA, which apparently starts the flow of ribosomes into polyribosome structures. Complete reactivation of translation by aminoacyl-tRNA occurs when mRNA from preformed mRNA-ribosome complexes, like the polyribosomes extracted from developing embryos or poly(U)-programmed ribosomes, are offered to quiescent embryo extracts. With respect to the mechanism of in vivo recharging of tRNAs, we observed that the level of several aminoacyl-tRNA synthetases increase during development. Methionyl-tRNA synthetase rises more than 10-fold. In the case of valyl-tRNA synthetase, the activation is lower and shown to be due to the de novo synthesis of its mRNA and the corresponding protein product as well. We conclude that protein synthesis and thereby the gradual animation of cryptobiotic Artemia embryos is determined to a large extent by the rate by which aminoacyl tRNAs are replenished during development at both the initiation and elongation level. PMID- 9360962 TI - Characterization of the Saccharomyces cerevisiae cytosine transporter using energizable plasma membrane vesicles. AB - The purine-cytosine permease is a carrier localized in the plasma membrane of the yeast Saccharomyces cerevisiae. The energetics of cytosine transport catalyzed by this permease has been studied in an artificial system obtained by fusion between proteoliposomes containing beef heart cytochrome c oxidase and plasma membrane enriched fractions of a S. cerevisiae strain overexpressing the permease. Upon addition of an energy donor, a proton-motive force (inside alkaline and negative) is created in this system and promotes cytosine accumulation. By using different phospholipids, it is shown that cytosine uptake is dependent on the phospholipids surrounding the carrier. It was demonstrated that the purine-cytosine permease is able to catalyze a secondary active transport of cytosine. By using nigericin and valinomycin, the DeltapH component of the proton-motive force is shown to be the only force driving nucleobase accumulation. Moreover, transport measurements done at two pH values have shown that alkalinization of intravesicular pH leads to a significant increase in cytosine uptake rate. Finally, no specific role of K+ ions on cytosine transport could be demonstrated in this system. PMID- 9360963 TI - Calnexin-dependent enhancement of nicotinic acetylcholine receptor assembly and surface expression. AB - The muscle-type nicotinic acetylcholine receptor (AChR)2 is a pentameric membrane ion channel assembled in the endoplasmic reticulum from four homologous subunits by mechanisms that are insufficiently understood. Nascent AChR subunits were recently found to form complexes with the endoplasmic reticulum-resident molecular chaperone calnexin. To determine the contribution of this interaction to AChR assembly and surface expression, we have now used transient transfection of mouse AChR subunits and calnexin into non-muscle cells. Co-transfection of calnexin along with AChR subunits into COS and HEK 293 cells was found to enhance AChR subunit folding and assembly, and to decrease degradation rates of newly synthesized AChR alpha-subunits, resulting in elevated surface expression of assembled AChR. Moreover, inhibition of the interaction between endogenous calnexin and AChR by castanospermine resulted in decreased AChR subunit folding, assembly, and surface expression in muscle and HEK 293 cells. Together, these findings provide evidence that calnexin directly contributes to AChR biogenesis by promoting subunit folding and assembly. PMID- 9360964 TI - Functional complementation of the yeast divalent cation transporter family SMF by NRAMP2, a member of the mammalian natural resistance-associated macrophage protein family. AB - The mammalian NRAMP gene family has two members, NRAMP1 and NRAMP2 that encode integral membrane proteins. Nramp1 is expressed exclusively in macrophages where it is found in the phagosomal membrane, and NRAMP1 mutations cause susceptibility to infection by abrogating the capacity of macrophages to control intracellular microbial replication. Nramp2 is highly similar to Nramp1, but is expressed in several tissues and cell types. The Nramp protein family is remarkably conserved throughout evolution, and recent data suggest that the mammalian Nramp2 and the yeast homologues Smf1 and Smf2 transport divalent cations. We tested whether structural similarity between the mammalian Nramp and the yeast Smf proteins results in functional complementation in yeast. Wild-type and mutant variants of the Nramp1 and Nramp2 proteins were expressed in a yeast mutant bearing null alleles at the SMF1 and SMF2 loci, and complementation of the phenotypes of this yeast mutant was investigated. Nramp2, but not Nramp1, was found to complement hypersensitivity to EGTA of the smf1/smf2 mutant under oxidative stress conditions (methyl viologen). We also observed that the smf1/smf2 double mutant is hypersensitive to growth at alkaline pH (pH 7.9) and that Nramp2 could complement this phenotype as well. Complementation by Nramp2 was specific and required a functional protein as independent mutations in residues highly conserved in all members of the Nramp family abrogated Nramp2 complementation. Since Mn2+ was the only divalent cation capable of completely suppressing both the EGTA and pH phenotypes, our results suggest that Nramp2 can transport Mn2+ in yeast. PMID- 9360965 TI - Multiple regulatory elements control transcription of the peripheral myelin protein zero gene. AB - The gene encoding protein zero (P0), the most abundant protein of peripheral nervous system myelin, is expressed uniquely in Schwann cells. Previous studies have demonstrated that much of the cell type specificity of this expression is due to transcriptional control elements in the 1.1-kilobase pair 5'-regulatory region of the gene. We have now analyzed this region and have identified a set of functional elements in the 500 base pairs proximal to the transcription start site. DNA sequence conservation within the 5' regions of the human, mouse, and rat P0 genes correlates closely with the results of promoter deletion analysis of the 1.1-kilobase pair region assayed in Schwann cell cultures and reveals a potent proximal region from position -350 to +45. Sites of protein/DNA interaction within the proximal 500 base pairs of the promoter were identified by footprinting assays. Functional transcriptional elements were identified within the protected regions in the proximal promoter by mutation and transient transfection analysis in P0-expressing cell lines. The core (or basal) P0 promoter is identified as two regulatory elements, a G/C-rich element that binds nuclear factor Sp1 and a CAAT box that binds NF-Y. These core elements are essential for the transcription observed from the transfected promoter in cultured Schwann cells. PMID- 9360966 TI - Induction of serum amyloid A (SAA) gene by SAA-activating sequence-binding factor (SAF) in monocyte/macrophage cells. Evidence for a functional synergy between SAF and Sp1. AB - Serum amyloid A (SAA) is a plasma protein that is associated with many inflammatory diseases including amyloidosis, arthritis, and atherosclerosis. SAA level is significantly increased during inflammatory condition, and such abnormal expression of this protein is linked to the pathogenesis of the above-mentioned diseases. A promoter element, designated as SAA-activating sequence (SAS), located between -280 and -226 has been implicated in the induction mechanism and a nuclear factor, SAS-binding factor (SAF), has been shown to bind to this region. In this report, using a cloned SAF gene in transient transfection assay, we provide evidence that SAF potentiates SAA gene expression through SAS element. Furthermore, we show that during lipopolysaccharide-mediated induction of SAF, heteromeric complex with transcription factor Sp1 is formed. Transfection assays using both transcription factor genes have demonstrated that SAF-Sp1 heteromer is a highly potent transactivator of SAA expression. PMID- 9360967 TI - KEX2 influences Candida albicans proteinase secretion and hyphal formation. AB - Candida albicans possesses at least seven differentially expressed genes that encode virulence-related secretory aspartyl proteinases (Saps). Sap DNA sequences predict post-translational processing at lysine-arginine residues in the preproteins, reminiscent of the maturation of Saccharomyces cerevisiae alpha factor, where a prepropolypeptide is converted into a biologically active pheromone by Kex2, a subtilisin-like proprotein convertase. To investigate involvement of a C. albicans KEX2 homologue in Sap activation, a genetic selection was performed based on KEX2 function. A kex2 strain of S. cerevisiae was transformed with a C. albicans genomic DNA library and screened for the production of active alpha-factor. Positive clones were assayed for killer toxin activity, another Kex2-dependent phenotype. Plasmids that rescued both defects contained a sequence encoding a protein homologous to S. cerevisiae Kex2. Both alleles of the C. albicans KEX2 were inactivated by successive mutations. Null mutants continued to secrete active Sap2; however, the enzyme was abnormally processed and secreted at reduced levels. Unexpectedly, null mutants were incapable of forming hyphae, instead differentiating into aberrantly shaped cells. The ability to normally process Sap2 and form hyphae was restored upon transformation of null mutants with a KEX2-containing plasmid. PMID- 9360968 TI - Butylated hydroxyanisole and its metabolite tert-butylhydroquinone differentially regulate mitogen-activated protein kinases. The role of oxidative stress in the activation of mitogen-activated protein kinases by phenolic antioxidants. AB - Phenolic antioxidant butylated hydroxyanisole (BHA) is a commonly used food preservative with broad biological activities, including protection against acute toxicity of chemicals, modulation of macromolecule synthesis and immune response, induction of phase II detoxifying enzymes, and especially its potential tumor promoting activities. Understanding the molecular basis underlying these diverse biological actions of BHA is thus of great importance. Here we demonstrate that BHA is capable of activating distinct mitogen-activated protein kinases (MAPKs), extracellular signal-regulated protein kinase 2 (ERK2), and c-Jun N-terminal kinase 1 (JNK1). Activation of ERK2 by BHA was rapid and transient, whereas the JNK1 activation was relatively delayed and persistent. A major metabolite of BHA, tert-butylhydroquinone (tBHQ), also activated ERK2 but weakly stimulated JNK1 activity. Furthermore, tBHQ activation of ERK2 was late and prolonged, showing a kinetics different from that induced by BHA. ERK2 activation by both compounds required the involvement of an upstream signaling kinase MAPK/ERK kinase (MEK), as evidenced by the inhibitory effect of a MEK inhibitor, PD98059. Pretreatment with N-acetyl-L-cysteine, glutathione, or vitamin E attenuated ERK2 but not JNK1 activation by BHA and tBHQ. Modulation of intracellular H2O2 levels by direct addition of catalase or pretreatment with a catalase inhibitor, aminotriazole, also affected BHA- and tBHQ-stimulated ERK2 activity but not JNK1, indicating the involvement of oxidative stress in the ERK2 activation by these two compounds. However, we did not observe any generation of H2O2 after exposure of cells to BHA or tBHQ using a H2O2-sensitive fluorescent probe, 2',7'-dichlorofluorescein diacetate. Instead, BHA and tBHQ substantially reduced the amount of intracellular H2O2. Furthermore, BHA and tBHQ activation of ERK2 was strongly inhibited by ascorbic acid and a peroxidase inhibitor, sodium azide, suggesting the potential role of phenoxyl radicals and/or their derivatives. Taken together, our results indicate that (i) BHA and its metabolite tBHQ differentially regulate MAPK pathways, and (ii) oxidative stress due to the generation of reactive intermediates, possibly phenoxyl radicals but not H2O2, is responsible for the ERK2 activation by BHA and tBHQ, whereas the JNK1 activation may require a distinct yet unknown mechanism. PMID- 9360969 TI - Characterization of reaction intermediates of human excision repair nuclease. AB - Nucleotide excision repair in humans is a complex reaction involving 14 polypeptides in six repair factors for dual incisions on either sides of a DNA lesion. To identify the reaction intermediates that form by the human excision repair nuclease, we adopted three approaches: purification of functional DNA.protein complexes, permanganate footprinting, and the employment as substrate of presumptive DNA reaction intermediates containing unwound sequences 5' to, 3' to, or encompassing the DNA lesion. The first detectable reaction intermediate was formed by substrate binding of XPA, RPA, XPC.HHR23B plus TFIIH (preincision complex 1, PIC1). In this complex the DNA was unwound on either side of the lesion by no more than 10 bases. Independent of the XPG nuclease function, the XPG protein stabilized this complex, forming a long lived preincision complex 2 (PIC2). The XPF.ERCC1 complex bound to PIC2, forming PIC3, which led to dual incisions and the release of the excised oligomer. With partially unwound DNAs, thymine cyclobutane dimer was excised at a fast rate independent of XPC.HHR23B, indicating that a major function of this protein is to stabilize the unwound DNA or to aid lesion unwinding in preincision complexes. PMID- 9360970 TI - Incorporation of norvaline at leucine positions in recombinant human hemoglobin expressed in Escherichia coli. AB - We report here a novel finding that norvaline can be incorporated in place of leucine in recombinant human hemoglobin expressed in Escherichia coli. The presence of the norvaline was confirmed by several analytical methods such as amino acid analysis, peptide mapping, electrospray mass spectrometry, and Edman protein sequencing. It appears that substitution is distributed across both the beta- and di-alpha-globins in purified recombinant hemoglobin. The level of misincorporation correlated with the ratio of the free norvaline/leucine pool available in the cell culture. This suggests that the incorporation of norvaline for leucine occurs through misaminoacylation of tRNALeu, similar to the misincorporation of norleucine for methionine found in many recombinant proteins expressed in E. coli. PMID- 9360971 TI - Tumor suppressor p53 is a negative regulator in thyroid hormone receptor signaling pathways. AB - Thyroid hormone nuclear receptors (TRs) are ligand-dependent transcription factors which regulate growth, differentiation, and development. The molecular mechanisms by which TRs mediate these diverse effects are unclear. One emerging hypothesis suggests that TRs could mediate these diverse effects via cooperation with different transcription factors/receptors. Indeed, we have recently shown that the human TR subtype beta1 (h-TRbeta1) interacts with the tumor suppressor p53. p53 is a transcription factor that plays a critical role in cell cycle regulation and tumor development. To assess the physiological relevance of the interaction of h-TRbeta1 with p53, the present study addressed the question as to whether the functions of h-TRbeta1 could be modulated by p53. We first compared the h-TRbeta1-mediated transcriptional activity in two pairs of isogenic cell lines, RKO/RKO E6 and MCF-7/MCF-7 E6. RKO and MCF-7 cells are colon and breast carcinoma cell lines, respectively, that contain p53 but lack TRbeta1. The isogenic RKO E6 and MCF-7 E6 cells are stable clones expressing high levels of papillomavirus type 16 E6 protein. In these cells, the level of p53 protein was lower than the parental cells. The impairment of p53 functions in these E6 containing cells led to an activation of TRbeta1-mediated transcriptional activity. Furthermore, in a growth hormone-producing cell line in which the expression of the growth hormone gene is positively regulated by TRs, overexpression of the wild-type p53 led to repression in the expression of the growth hormone gene. Thus, TRs could cross-talk with p53 in its signaling pathways to regulate gene regulatory functions. The present findings further strengthen the hypothesis that mediation of the pleiotropic effects of T3 requires the cooperation of TRs with a large network of transcription factors. PMID- 9360972 TI - Kinetic partitioning. Poising SecB to favor association with a rapidly folding ligand. AB - Chaperones are a class of proteins that possess the remarkable ability to selectively bind polypeptides that are in a nonnative state. The selectivity of SecB, a molecular chaperone in Escherichia coli, for its ligands can be explained in part by a kinetic partitioning between folding of the polypeptide and association with SecB. It has clearly been established that kinetic partitioning can be poised to favor association with SecB by changing the rate constant for folding of the ligand. We now demonstrate that binding to SecB can be given a kinetic advantage over the pathway for folding by modulating the properties of the chaperone. By poising SecB to expose a hydrophobic patch, we were able to detect a complex between SecB and maltose-binding protein under conditions in which rapid folding of the polypeptide otherwise precludes formation of a kinetically stable complex. The data presented here are interpreted within the framework of a kinetic partitioning between binding to SecB and folding of the polypeptide. We propose that exposure of a hydrophobic patch on SecB increases the surface area for binding and thereby increases the rate constant for association. In this way association of SecB with the polypeptide ligand has a kinetic advantage over the pathway for folding. PMID- 9360973 TI - Construction of chimeric enzymes out of maize endosperm branching enzymes I and II: activity and properties. AB - Branching enzyme I and II isoforms from maize endosperm (mBE I and mBE II, respectively) have quite different properties, and to elucidate the domain(s) that determines the differences, chimeric genes consisting of part mBE I and part mBE II were constructed. When expressed under the control of the T7 promoter in Escherichia coli, several of the chimeric enzymes were inactive. The only fully active chimeric enzyme was mBE II-I BspHI, in which the carboxyl-terminal part of mBE II was exchanged for that of mBE I at a BspHI restriction site and was purified to homogeneity and characterized. Another chimeric enzyme, mBE I-II HindIII, in which the amino-terminal end of mBE II was replaced with that of mBE I, had very little activity and was only partially characterized. The purified mBE II-I BspHI exhibited higher activity than wild-type mBE I and mBE II when assayed by the phosphorylase a stimulation assay. mBE II-I BspHI had substrate specificity (preference for amylose rather than amylopectin) and catalytic capacity similar to mBE I, despite the fact that only the carboxyl terminus was from mBE I, suggesting that the carboxyl terminus may be involved in determining substrate specificity and catalytic capacity. In chain transfer experiments, mBE II-I BspHI transferred more short chains (with a degree of polymerization of around 6) in a fashion similar to mBE II. In contrast, mBE I-II HindIII transferred more long chains (with a degree of polymerization of around 11-12), similar to mBE I, suggesting that the amino terminus of mBEs may play a role in the size of oligosaccharide chain transferred. This study challenges the notion that the catalytic centers for branching enzymes are exclusively located in the central portion of the enzyme; it suggests instead that the amino and carboxyl termini may also be involved in determining substrate preference, catalytic capacity, and chain length transfer. PMID- 9360974 TI - Inhibition of CD4 translation mediated by human immunodeficiency virus type 1 envelope protein in a cell-free system. AB - The human immunodeficiency virus type 1 (HIV-1) employs a number of complex strategies to interfere with the synthesis, stability, and subcellular localization of its specific cellular receptor CD4. To define better the mechanisms of inhibition of CD4 expression, we used a rabbit reticulocyte lysate in vitro system, in which cDNAs derived from HIV-1-infected cells were used to generate mRNA for the Tat, Vpu, and gp160 envelope proteins that were translated together with CD4-encoding mRNA. In the presence of microsomal membranes, we observed that cotranslation of Env mRNA resulted in a dose-dependent inhibition of CD4 translation. This effect was enhanced further when an mRNA-encoding Vpu in addition to Env mRNA was utilized. However, the activity of Vpu was mostly post translational, since translation of Vpu alone, but not Env, was able to destabilize CD4 molecules presynthesized into microsomes. The Env-mediated inhibitory effect was specifically targeted at CD4 and did not affect the synthesis or stability of the CD8 molecule. Interestingly, mutated CD4 species, with a 20-fold lower affinity for HIV-1 Env than wild-type, were less sensitive to cotranslational inhibition. Our report identifies the envelope as the HIV-1 protein responsible for down-regulation of CD4 translation. We further propose a mechanism whereby direct interactions between gp160 and nascent CD4 molecules can cause interference with and premature termination of CD4 protein elongation. PMID- 9360975 TI - Probing of the membrane topology of sarcoplasmic reticulum Ca2+-ATPase with sequence-specific antibodies. Evidence for plasticity of the c-terminal domain. AB - The topology of Ca2+-ATPase in sarcoplasmic reticulum (SR) vesicles was investigated with the aid of sequence-specific antibodies, produced against oligopeptides corresponding to sequences close to the membranous portions of the protein. The antisera in competitive enzyme-linked immunosorbent assays only reacted with intact SR vesicles to a limited extent, but most epitopic regions were exposed by low concentrations of nondenaturing detergent, octaethylene glycol dodecyl ether (C12E8) or after removal of cytosolic regions by proteinase K. In particular, these treatments exposed the loop regions in the C-terminal domain, including L7-8, the loop region located between transmembrane segments M7 and M8, with a putative intravesicular position, which had immunochemical properties very similar to those of the C terminus with a documented cytosolic exposure. In contrast to this, the reactivity of the N-terminal intravesicular loop regions L1-2 and L3-4 was only increased by C12E8 treatment but not by proteinase K proteolysis. Complexation of Ca2+-ATPase with beta,gamma-CrATP stabilized the C-terminal domain of Ca2+-ATPase against proteinase K proteolysis and reaction with most of the antisera, but immunoreactivity was maintained by the L6-7 and L7-8 loops. Immunoelectron microscopic analyses of vesicles following negative staining, thin sectioning, and the SDS-digested freeze fracture labeling method suggested that the L7-8 epitope, in contrast to L6-7 and the C terminus, can be exposed on either the intravesicular or cytosolic side of the membrane. A preponderant intravesicular location of L7-8 in intact vesicles is suggested by the susceptibility of this region to proteolytic cleavage after disruption of the vesicular barrier with C12E8 and in symmetrically reconstituted Ca2+-ATPase proteoliposomes. In conclusion, our data suggest an adaptable membrane insertion of the C-terminal Ca2+-ATPase domain, which under some conditions permits sliding of M8 through the membrane with cytosolic exposure of L7-8, of possible functional significance in connection with Ca2+ translocation. On the technical side, our data emphasize that extreme caution is needed when using nondenaturing detergents or other treatments like EGTA at alkaline pH to open up vesicles for probing of intravesicular location with antibodies. PMID- 9360976 TI - Identification of the key protein for zinc uptake in Hemophilus influenzae. AB - Very little is known about specific mechanisms for zinc accumulation and transport in bacteria. In this study a putative adhesin B in Hemophilus influenzae, the product of gene HI0119, has been identified as a periplasmic zinc binding protein (PZP1). A pzp1-deficient mutant has been constructed which is defective for growth under aerobic conditions and grows poorly under anaerobic conditions. The growth defect is specifically rescued by supplementing the growth medium with high concentrations of zinc. Subcellular fractionation was used to localize PZP1 to the periplasmic region in a nontypeable H. influenzae strain and in a transfected recombinant Escherichia coli strain (TApzp1). Recombinant PZP1, purified from a periplasmic extract of E. coli strain TApzp1, contained approximately two zinc atoms/protein molecule as determined by neutron activation analysis and atomic absorption spectroscopy. The zinc atoms could be removed by incubation with EDTA, and, by further addition of zinc, a total of five zinc atoms/PZP1 could be bound. Direct binding of 65Zn to the recombinant protein by Western blot was demonstrated. Taken together, these results provide direct evidence that PZP1 plays a key role in zinc uptake by H. influenzae. PMID- 9360977 TI - The efficient catabolism of thrombin-protease nexin 1 complexes is a synergistic mechanism that requires both the LDL receptor-related protein and cell surface heparins. AB - Protease nexin 1 (PN1) is a serine protease inhibitor (SERPIN) that acts as a suicide substrate for thrombin (Th) and urokinase-type plasminogen activator (uPA). PN1 forms 1:1 stoichiometric complexes with these proteases, which are then rapidly bound, internalized, and degraded. The low density lipoprotein receptor-related protein (LRP) is the receptor responsible for the internalization of protease-PN1 complexes. However, we found that the LRP is not significantly involved in the initial cell surface binding of thrombin-PN1, leading us to investigate what cellular component was responsible for this initial interaction. Since Th-PN1 complexes retain a high-affinity for heparin after complex formation, unlike several of the other SERPINs, we tested the possibility that cell surface heparins were involved in initial complex binding. Soluble heparin was found to be a potent inhibitor of the binding of Th-PN1 to the cell surface and greatly facilitated the dissociation of Th-PN1 complexes pre bound in the absence of soluble heparin. To ascertain the role of cell surface heparins, further studies were done using complexes of thrombin and PN1(K7E), a variant of PN1 in which the heparin binding site was rendered non-functional. When added at equal initial concentrations of complexes, Th-PN1(K7E) was catabolized 5- to 10-fold less efficiently than Th-PN1, a direct result of the greatly diminished initial binding of the Th-PN1(K7E) complexes. These data demonstrate the sizable contribution of cell surface heparins to Thrombin-PN1 complex binding and support a model in which these heparins act to concentrate the complexes at the cell surface facilitating their subsequent LRP-dependent endocytosis. PMID- 9360978 TI - Nonphosphorylated peptide ligands for the Grb2 Src homology 2 domain. AB - Critical intracellular signals in normal and malignant cells are transmitted by the adaptor protein Grb2 by means of its Src homology 2 (SH2) domain, which binds to phosphotyrosyl (pTyr) residues generated by the activation of tyrosine kinases. To understand this important control point and to design inhibitors, previous investigations have focused on the molecular mechanisms by which the Grb2 SH2 domain selectively binds pTyr containing peptides. In the current study, we demonstrate that the Grb2 SH2 domain can also bind in a pTyr independent manner. Using phage display, an 11-amino acid cyclic peptide, G1, has been identified that binds to the Grb2 SH2 domain but not the src SH2 domain. Synthetic G1 peptide blocks Grb2 SH2 domain association (IC50 10-25 microM) with a 9-amino acid pTyr-containing peptide derived from the SHC protein (pTyr317). These data and amino acid substitution analysis indicate that G1 interacts in the phosphopeptide binding site. G1 peptide requires a YXN sequence similar to that found in natural pTyr-containing ligands, and phosphorylation of the tyrosine increases G1 inhibitory activity. G1 also requires an internal disulfide bond to maintain the active binding conformation. Since the G1 peptide does not contain pTyr, it defines a new type of SH2 domain binding motif that may advance the design of Grb2 antagonists. PMID- 9360979 TI - Structural characterization of an abnormally cross-linked muropeptide dimer that is accumulated in the peptidoglycan of methicillin- and cefotaxime-resistant mutants of Staphylococcus aureus. AB - Laboratory mutants of Staphylococcus aureus strain ATCC 8325 (27S) selected for increased minimal inhibitory concentration (MIC) values to methicillin and cefotaxime showed increased rates of cell wall turnover and detergent-induced autolysis in virtual parallel with the increasing MIC for the antibiotic. Also in parallel with the increasing MICs for the particular antibiotic used in the selection was the gradual accumulation of an unusual muropeptide in the peptidoglycan of the mutants, muropeptide 12, which is a minor component of the cell wall of the parental strain. Analysis of muropeptide 12, its peptide derivative, and its lysostaphin degradation products by high pressure liquid chromatography, Edman degradation, and mass spectrometry suggests that muropeptide 12 is a dimer in which the two monomeric components are interlinked by two pentaglycyl cross-bridges, thus generating a 14-member macrocyclic ring structure. This unusual cross-linked structure may be the product of the abnormal activity of penicillin-binding protein 2 which has grossly reduced antibiotic binding capacity in the mutant staphylococci. PMID- 9360980 TI - GA-binding protein-dependent transcription initiator elements. Effect of helical spacing between polyomavirus enhancer a factor 3(PEA3)/Ets-binding sites on initiator activity. AB - Many eukaryotic RNA polymerase II promoters contain initiator elements which direct accurate transcription in a TATA-independent manner. The PEA3/Ets-binding site (PEA3/EBS) is a common enhancer element in eukaryotic genes and is also found near the transcriptional start sites of many TATA-less promoters. We demonstrate that two PEA3/EBSs driving expression of the luciferase reporter gene, function as a minimal transcriptional initiator element. Maximal levels of transcription was achieved when two PEA3/EBSs, in either orientation, were located on the same face of the DNA helix, and the sites could be separated by up to three helical turns. In vitro transcription start sites directed by PEA3/EBS elements were clustered on either side of the upstream PEA3/EBS and were abolished by immunodepletion of GA-binding protein (GABP) from FM3A cell nuclear extracts. In vivo, co-transfection of GABPalpha and GABPbeta expression vectors enhanced reporter gene expression driven from PEA3/EBS initiator elements. Like other initiator elements, the PEA3/EBS elements were activated synergistically by upstream Sp1-binding sites. Thus, our results establish GABP as both a transcriptional activator factor and as an initiator factor. PMID- 9360981 TI - Assembly of the warfarin-sensitive vitamin K 2,3-epoxide reductase enzyme complex in the endoplasmic reticulum membrane. AB - gamma-Carboxylation of vitamin K-dependent proteins requires a functional vitamin K cycle to produce the active vitamin K cofactor for the gamma-carboxylase which posttranslationally modifies precursors of these proteins to contain gamma carboxyglutamic acid residues. The warfarin-sensitive enzyme vitamin K epoxide reductase (VKOR) of the cycle reduces vitamin K 2,3-epoxide to the active vitamin K hydroquinone cofactor. Because of the importance of warfarin as an anticoagulant in prophylactic medicine and as a poison in rodent pest control, numerous attempts have been made to understand the molecular mechanism underlying warfarin-sensitive vitamin K 2,3-epoxide reduction. In search for protein components that could be involved in this reaction we designed an in vitro gamma carboxylation test system where the warfarin-sensitive VKOR produces the cofactor for the gamma-carboxylase. Dissection of this system by chromatographic techniques has identified a member(s) of the glutathione S-transferase gene family as one component of the VKOR enzyme complex in the endoplasmic reticulum membrane. The affinity-purified glutathione S-transferase(s) was sensitive to warfarin but lost its warfarin sensitivity and glutathione S-transferase activity upon association with lipids in the presence of Mn2+ or Ca2+. In the gamma carboxylation test system, loss of warfarin-sensitive glutathione S-transferase activity coincided with formation of the VKOR enzyme complex. It is proposed that formation of VKOR in the endoplasmic reticulum membrane resembles formation of the lipoxygenase enzyme complex where the glutathione S-transferase-related FLAP protein binds cytosolic lipoxygenase to form a membrane enzyme complex. PMID- 9360982 TI - Non-capacitative calcium entry in Chinese hamster ovary cells expressing the platelet-derived growth factor receptor. AB - Platelet-derived growth factor (PDGF) is believed to produce intracellular calcium (Ca2+i) transients by inositol trisphosphate (InsP3)-mediated release of intracellular Ca2+ stores followed by "capacitative" Ca2+ entry due to emptying of these stores. We examined the roles for the phospholipase Cgamma-InsP3 pathway and the emptying of InsP3-dependent intracellular Ca2+ stores in PDGF-mediated Ca2+ entry. Intracellular Ca2+ release and Ca2+ entry were measured with fluorometric methods in Chinese hamster ovary cells expressing wild type or mutant PDGF receptors. Activation of the wild type PDGF receptor caused both intracellular "Ca2+ release, " measured in nominally 0 Ca2+ extracellular medium, and "Ca2+ entry, " measured upon addition of 2 mM Ca2+ medium. Both phases were absent in Chinese hamster ovary cells expressing a PDGF receptor mutant (Y977F,Y989F) that fails to bind phospholipase Cgamma. Blockade of the InsP3 receptor, by microinjection of single cells with low molecular weight heparin (5 50 mg/ml), blocked only Ca2+i release (following PDGF or flash photolysis of caged InsP3) and had no effect on PDGF-induced Ca2+ entry. In whole cell patch clamp experiments, intracellular heparin also failed to block PDGF-evoked ion currents. Release of InsP3-dependent intracellular Ca2+ stores, by flash photolysis of caged InsP3, was apparently not sufficient to maximally activate Ca2+ entry. Intracellular InsP3 caused significantly less Ca2+ entry than PDGF alone. These data suggest that InsP3 alone is not sufficient to maximally activate Ca2+ entry by the capacitative pathway and that products of phosphatidylinositol 4,5-bisphosphate breakdown other than InsP3 probably play a role in PDGF-mediated Ca2+ entry. PMID- 9360983 TI - Tyrosine phosphorylation of Crk-associated substrates by focal adhesion kinase. A putative mechanism for the integrin-mediated tyrosine phosphorylation of Crk associated substrates. AB - Integrin-ligand binding induces the tyrosine phosphorylation of various proteins including focal adhesion kinase (pp125(FAK)) and Crk-associated substrate (Cas). FAK is activated and autophosphorylated by the ligation of integrins, although the substrate of FAK has not been revealed. We show here that p130(Cas) and Cas-L are FAK substrates. FAK directly phosphorylates Cas proteins primarily at the YDYVHL sequence that is conserved among all Cas proteins. Furthermore, the phosphorylated YDYVHL sequence is a binding site for Src family protein-tyrosine kinases, and the recruited Src family kinase phosphorylates the other tyrosine residues within Cas. The Cas-L YDYVHL sequence is phosphorylated upon integrin ligand binding, and this integrin-mediated tyrosine phosphorylation is inhibited by the cotransfection of the FAK COOH-terminal domain that does not contain a kinase domain. These findings strongly suggest that FAK initiates integrin mediated tyrosine phosphorylation of Cas proteins; then, Src family tyrosine kinases, which are recruited to phosphorylated Cas and FAK, further phosphorylate Cas proteins. PMID- 9360984 TI - Activation of p53-p21waf1 pathway in response to disruption of cell-matrix interactions. AB - The proliferation of most cells is strictly dependent on cell-matrix interactions, a phenomenon called anchorage dependence. Because tumor cells often are independent of this regulation, it is important to characterize the molecular pathways that control cellular proliferation after detachment of cells from their matrix. In this report, we investigated a possible role of p53 and one of its target genes, p21(waf1/cip1), as components of anchorage-dependent cell growth control. We found that p53 protein is rapidly activated upon the disruption of cellular attachment. This led to p21 transcriptional activation via two p53 binding sites in its promoter. Elevated p21 protein levels blocked transcription and activity of the cell cycle-regulator cyclin A, and cells became arrested in G1 of the cell cycle. Under the same conditions, fibroblasts from p53 knock-out mice did not activate p21 and did not down-regulate cyclin A expression but rather induced another cell cycle inhibitor, p27. Thus, our results characterize a chain of events, starting from the activation of p53 and proceeding via p21 to cyclin A, that is activated in response to the loss of cellular adherence. This p53-regulated pathway may constitute one of a few redundant systems to ensure proper cell control in multicellular organisms. PMID- 9360985 TI - Influence of protein-glutathione mixed disulfide on the chaperone-like function of alpha-crystallin. AB - In an earlier report we showed that incubation of alpha-crystallin with oxidized glutathione results in significant loss of its chaperone-like activity. In the present study, we determined the effect of protein-glutathione mixed disulfides (PSSG), formed at Cys-131 in bovine alphaA-crystallin, and Cys-131 and Cys-142 in human alphaA-crystallin, on the function of alpha-crystallin as a molecular chaperone. After incubation of calf and young human alphaL-crystallin fractions with oxidized glutathione, levels of PSSG were determined by performic acid oxidation of the mixed disulfides followed by reversed-phase high pressure liquid chromatography separation of phenylisothiocyanate-derivatized glutathione sulfonic acid. Levels of PSSG increased from 0.01 to 0.14 nmol/nmol (20 kDa) in bovine alphaL-crystallin and from 0.022 to 0.25 nmol/nmol in human alphaL crystallin. The presence of glutathione adducts at Cys-131 and Cys-142 were confirmed by mass spectral analysis. The chaperone-like activity was determined by the heat denaturation assay using betaL-crystallin as the target protein. To examine the reversibility of the effect of mixed disulfides on chaperone activity, studies were done before and after reduction with the glutathione reductase system. Increased levels of PSSG resulted in lower chaperone activities. Treatment with the glutathione reductase system led to 80% reduction in PSSG levels with a concomitant recovery of the chaperone activity. These results suggest that cysteine(s) in the alphaA-crystallin subunit play an important role in the function of alpha-crystallin as a molecular chaperone. PMID- 9360986 TI - Cloning, chromosome localization, expression, and characterization of an Src homology 2 and pleckstrin homology domain-containing insulin receptor binding protein hGrb10gamma. AB - hGrb10alpha (previously named Grb-IR) is a Src-homology 2 domain-containing protein that binds with high affinity to the tyrosine-phosphorylated insulin receptor and insulin-like growth factor-1 receptor. At least two isoforms of human Grb10, (hGrb10alpha and hGrb10beta), which differ in the pleckstrin homology (PH) domain and the N-terminal sequence, have previously been identified in insulin target tissues such as human skeletal muscle and fat cells. Here we report the cloning of the third isoform of the hGrb10 family (hGrb10gamma) from human skeletal muscle and its localization to human chromosome 7. We have also determined the human chromosome localization of Grb7 to 17q21-q22 and Grb14 to chromosome 2. hGrb10gamma contains an intact PH domain and an N-terminal sequence that is present in hGrb10alpha but absent in hGrb10beta. RNase protection assays and Western blot analysis showed that hGrb10alpha and hGrb10gamma are differentially expressed in insulin target cells including skeletal muscle, liver, and adipocyte cells. hGrb10gamma is also expressed in HeLa cells and various breast cancer cell lines. The protein bound with high affinity to the insulin receptor in cells, and the interaction was dependent on the tyrosine phosphorylation of the receptor. hGrb10gamma also underwent insulin-stimulated membrane translocation and serine phosphorylation. hGrb10gamma phosphorylation was inhibited by PD98059, a specific inhibitor of mitogen-activated protein kinase kinase, and wortmannin, a specific inhibitor of phosphatidylinositol 3 kinase. Taken together, our data suggest that hGrb10 isoforms are potential downstream signaling components of the insulin receptor tyrosine kinase and that the PH domain may play an important role in the involvement of these isoforms in signal transduction pathways initiated by insulin and other growth factors. PMID- 9360987 TI - Two hepatic enhancers, HCR.1 and HCR.2, coordinate the liver expression of the entire human apolipoprotein E/C-I/C-IV/C-II gene cluster. AB - We show that the liver-specific expression of all four genes in the human apolipoprotein (apo) E/C-I/C-IV/C-II gene cluster in transgenic mice is determined by the coordinate action of two distinct hepatic control regions (HCR). These enhancers are positioned 15 kilobases (kb) (HCR.1) and 26 kb (HCR.2) downstream of the apoE gene. To investigate the action of each HCR, transgenic mice were generated with a 70-kb human genomic fragment that contained the complete apoE gene cluster or with this fragment modified by the specific deletion of HCR.1, HCR.2, or both HCR domains. Hepatic expression of all four apolipoprotein genes was observed in transgenic mice in which either HCR.1 or HCR.2 was deleted, but no transgene expression was found in the liver in the absence of both HCR domains. The overall patterns of transgene expression suggested that HCR.2 was the dominant element for apoC-IV and apoC-II expression and that HCR.1 was dominant for the apoE/C-I expression. No liver-specific transcriptional activity was identified for the proximal promoter of any gene in the cluster; all liver-specific activity was associated with HCR.1 and HCR.2. Thus, the HCRs of the apoE gene cluster constitute unique regulatory domains for determining the requirements for apolipoprotein gene expression in the liver. PMID- 9360988 TI - CCAAT-enhancer-binding proteins (C/EBP) regulate the tissue specific activity of the CD11c integrin gene promoter through functional interactions with Sp1 proteins. AB - The CD11c/CD18 integrin binds lipopolysaccharide, fibrinogen, and heparin, and mediates leukocyte adhesion, spreading, and migration. CD11c/CD18 is primarily found on myeloid cells and its expression is regulated during myeloid differentiation by transcriptional mechanisms acting on the CD11c gene promoter. We now describe that CCAAT/enhancer-binding proteins (C/EBP) contribute to the basal, tissue-specific and developmentally regulated activity of the CD11c promoter. A C/EBP-binding site within the CD11c promoter (CEBP-80) is bound by CEBPalpha in undifferentiated U937 cells and by C/EBPalpha- and C/EBPbeta containing dimers in phorbol 12-myristate 13-acetate-differentiating cells, and its disruption decreased the CD11c promoter activity in a cell type-dependent manner. C/EBPalpha transactivated the CD11c promoter through the CEBP-80 element, and C/EBPalpha transactivation was also dependent on the Sp1-70- and Sp1-120 Sp1 binding sites. The -90/-50 fragment from the CD11c promoter, containing the adjacent CEBP-80, Sp1-70, and AP1-60 sites, differentially enhanced the activity of the minimal prolactin promoter in hematopoietic and epithelial cells. Altogether, these results demonstrate that C/EBP factors participate in the tissue-restricted and regulated expression of the CD11c/CD18 integrin through functional interactions with Sp1, suggest that Sp1-related factors modulate C/EBPalpha transcriptional activity on the CD11c promoter, and demonstrate the existence of a composite regulatory element recognized by C/EBP, Sp1, and AP-1 factors and whose enhancing effects are cell-type dependent. PMID- 9360989 TI - Major histocompatibility complex class II-dependent unfolding, transport, and degradation of endogenous proteins. AB - We have analyzed the ability of major histocompatibility (MHC) class II molecules to capture proteins in the biosynthetic pathway and whether this may be associated with MHC class II-dependent antigen processing. When coexpressed with HLA-DR 4 molecules in HeLa cells, influenza hemagglutinin was inhibited from folding and trimerization in the biosynthetic pathway, targeted to endosomal compartments, and rapidly degraded. Due to the interaction with MHC class II molecules, therefore, unfolded forms of hemagglutinin were bypassing the quality control mechanism of the secretory pathway. More important, however, the transport, endocytosis, and rapid degradation of unfolded hemagglutinin in the presence of MHC class II molecules suggest that proteins captured in the endoplasmic reticulum by class II molecules may become substrates for antigen processing and presentation to CD4-positive T cells. In insect cells we show that this phenomenon is not restricted to a few proteins such as hemagglutinin. A highly heterogeneous mixture of proteins from the endoplasmic reticulum including coexpressed hemagglutinin can form stable complexes with soluble HLA-DR alpha and beta chains that were transported into the supernatant. This mechanism may gain biological significance in abnormal situations associated with accumulation of unfolded or malfolded proteins in the endoplasmic reticulum, for example during viral infections. PMID- 9360991 TI - Cephalosporin substrate specificity determinants of TEM-1 beta-lactamase. AB - beta-lactamase is a bacterial enzyme that catalyzes the hydrolysis of beta-lactam antibiotics such as penicillins and cephalosporins. TEM-1 beta-lactamase is a prevalent beta-lactamase found in Gram-negative bacteria and is capable of hydrolyzing both penicillins and cephalosporins, except for the extended-spectrum cephalosporins. To identify the sequence determinants in the active site for a given antibiotic substrate, random libraries were constructed that each contain all possible amino acid combinations for the designated region of TEM-1 beta lactamase. To establish the determinants of substrate specificity for cephalosporins versus those for penicillins, these active site libraries have been screened for mutants with high levels of activity for the second generation cephalosporin cephaloridine. Based on the sequence results, substitutions of W165S, A237T, and E240C were identified as cephalosporin-specific. Kinetic analysis of these mutants was done to determine whether each is capable of distinguishing between the two classes of antibiotics. Both the A237T and E240C substitutions, alone or in combination, exhibited increased cephalosporinase activity and decreased penicillinase activity relative to the wild-type enzyme. A sequence comparison between functional mutants selected for cephaloridine hydrolytic activity and functional mutants previously selected for ampicillin hydrolytic activity suggests that TEM-1 beta-lactamase has greater restrictions in maintaining cephalosporinase activity versus maintaining penicillinase activity. PMID- 9360990 TI - Expression of heparin-binding epidermal growth factor-like growth factor during pancreas development. A potential role of PDX-1 in transcriptional activation. AB - The development of the pancreas appears to be regulated by various growth factors. We report here the expression of heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) in the developing pancreas. Immunostaining of fetal and neonatal rat pancreata, in which endocrine cells are visible as cell clusters often associated with primitive ducts or ductular cells, revealed that most of the cluster-forming cells and primitive ducts or ductular cells express HB-EGF protein. In contrast, the exocrine pancreas lacked HB-EGF expression. Based on findings that the expression pattern was similar to that of the homeodomain-containing transcription factor PDX-1 (IDX-1/STF-1/IPF1) and that the regulatory region of the HB-EGF gene contained sequences similar to the PDX-1 binding A element, we examined whether PDX-1 could be a potential activator of HB EGF gene expression. The results of reporter gene analyses suggested that the HB EGF gene promoter is PDX-1-responsive and that the activity of the promoter in pancreatic beta cell-derived betaTC1 cells depends on the PDX-1 binding site-like sequences. Gel-mobility shift analyses using an anti-PDX-1 antibody indicated that PDX-1 is a specific and dominant binding factor for an A element-like sequence in the HB-EGF gene. These observations suggest the possible involvement of HB-EGF in pancreas development. While PDX-1 is essential for pancreas development, HB-EGF may function as a mediator of PDX-1 and thus be involved in the development of the endocrine pancreas. PMID- 9360992 TI - Characterization and retinoic acid responsiveness of the murine Hoxd4 transcription unit. AB - We have characterized the transcription unit of a murine Hox gene in the fourth paralogous group, Hoxd4. We have identified two Hoxd4 transcription start sites by S1 analysis. The upstream promoter (P2) is 5.2 kilobase pairs upstream from the coding region, while the downstream promoter (P1) is 1.1 kilobase pairs distant. Both promoters bear a cluster of start sites. Multiple transcripts were identified by Northern blot, originating from both promoters and multiple polyadenylation signals. Expression of P1 transcripts in the neural tube shows an anterior border at the rhombomere 6/7 boundary, corresponding to previous reports (Gaunt, S. J., Krumlauf, R., and Duboule, D. (1989) Development 107, 131-141; Morrison, A., Moroni, M. C., Ariza-McNaughton, L., Krumlauf, R., and Mavilio, F. (1996) Development 122, 1895-1907). A more posterior boundary in the central nervous system was observed for P2 transcripts. We observed strong expression up to somite 6 and weak expression in somite 5, correlating with the phenotype of Hoxd4 null mutant mice (Horan, G. S. B., Nagy Kovacs, E., Behringer, R. R., and Featherstone, M. S. (1995) Dev. Biol. 169, 359-372). In response to retinoic acid, expression from P1 in the hindbrain was anteriorized after 4 or 24 h of treatment. P2 transcripts seemed to be less responsive and/or to have an indirect response to retinoic acid. The long 5'-untranslated region found in all Hoxd4 transcripts suggests that translation does not occur by a classical ribosome scanning mechanism. PMID- 9360993 TI - Mouse mast cell protease 9, a novel member of the chromosome 14 family of serine proteases that is selectively expressed in uterine mast cells. AB - Mouse mast cell protease (mMCP) 1, mMCP-2, mMCP-4, and mMCP-5 are members of a family of related serine proteases whose genes reside within an approximately 850 kilobase (kb) complex on chromosome 14 that does not readily undergo crossover events. While mapping the mMCP-1 gene, we isolated a novel gene that encodes a homologous serine protease designated mMCP-9. The mMCP-9 and mMCP-1 genes are only approximately 7 kb apart on the chromosome and are oriented back to back. The proximity of the mMCP-1 and mMCP-9 genes now suggests that the low recombination frequency of the complex is due to the closeness of some of its genes. The mMCP-9 transcript and protein were observed in the jejunal submucosa of Trichinella spiralis-infected BALB/c mice. However, in normal BALB/c mice, mMCP-9 transcript and protein were found only in those mast cells that reside in the uterus. Thus, the expression of mMCP-9 differs from that of all other chymases. The observation that BALB/c mouse bone marrow-derived mast cells developed with interleukin (IL) 10 and c-kit ligand contain mMCP-9 transcript, whereas those developed with IL-3 do not, indicates that the expression of this particular chymase is regulated by the cytokine microenvironment. Comparative protein structure modeling revealed that mMCP-9 is the only known granule protease with three positively charged regions on its surface. This property may allow mMCP-9 to form multimeric complexes with serglycin proteoglycans and other negatively charged proteins inside the granule. Although mMCP-9 exhibits a >50% overall amino acid sequence identity with its homologous chymases, it has a unique substrate-binding cleft. This finding suggests that each member of the chromosome 14 family of serine proteases evolved to degrade a distinct group of proteins. PMID- 9360994 TI - Phosphatidylinositol 3-kinase in interleukin 1 signaling. Physical interaction with the interleukin 1 receptor and requirement in NFkappaB and AP-1 activation. AB - The signaling mechanisms utilized by the proinflammatory cytokine interleukin-1 (IL-1) to activate the transcription factors NFkappaB and activator protein-1 (AP 1) are poorly defined. We present evidence here that IL-1 not only stimulates a dramatic increase in phosphatidylinositol 3-kinase (PI 3-kinase) activity but also induces the physical interaction of its type I receptor with the p85 regulatory subunit of PI 3-kinase. Furthermore, two PI 3-kinase-specific inhibitors, wortmannin and a dominant-negative mutant of the p85 subunit, inhibited IL-1-induced activation of both NFkappaB and AP-1. Transient transfection experiments indicated that whereas overexpression of PI 3-kinase may be sufficient to induce AP-1 and increase nuclear c-Fos protein levels, PI 3 kinase may need to cooperate with other IL-1-inducible signals to fully activate NFkappaB-dependent gene expression. In this regard, cotransfection studies suggested that PI 3-kinase may functionally interact with the recently-identified IL-1-receptor-associated kinase to activate NFkappaB. Our results thus indicate that PI 3-kinase is a novel signal transducer in IL-1 signaling and that it may differentially mediate the activation of NFkappaB and AP-1. PMID- 9360995 TI - Generation of monoclonal antibodies to integrin-associated proteins. Evidence that alpha3beta1 complexes with EMMPRIN/basigin/OX47/M6. AB - The alpha3beta1 integrin forms complexes with other cell-surface proteins, including transmembrane-4 superfamily (TM4SF) proteins (e. g. CD9, CD53, CD63, CD81, and CD82). To identify additional cell-surface proteins associated with alpha3beta1 integrin, a monoclonal antibody selection protocol was developed. Mice were immunized with integrin alpha3beta1-containing complexes isolated from HT1080 fibrosarcoma cells, and then 712 hybridoma clones were produced, and 95 secreted antibodies that recognized the HT1080 cell surface. Among these, 12 antibodies directly recognizing integrin alpha3 or beta1 subunits were eliminated. Of the remaining 83, 16 co-immunoprecipitated proteins that resembled integrins under non-stringent detergent conditions. These 16 included 15 monoclonal antibodies recognizing EMMPRIN/basigin/OX-47/M6, a 45-55-kDa transmembrane protein with two immunoglobulin domains. The EMMPRIN protein associated with alpha3beta1 and alpha6beta1, but not alpha2beta1 or alpha5beta1, as shown by reciprocal immunoprecipitation experiments. Also, association with alpha3beta1 was confirmed by cell-surface cross-linking and immunofluorescence co localization experiments. Importantly, EMMPRIN-alpha3beta1 complexes appear not to contain TM4SF proteins, suggesting that they are distinct from TM4SF protein alpha3beta1 complexes. PMID- 9360996 TI - NAG-2, a novel transmembrane-4 superfamily (TM4SF) protein that complexes with integrins and other TM4SF proteins. AB - Transmembrane-4 superfamily (TM4SF) proteins form complexes with integrins and other cell-surface proteins. To further characterize the major proteins present in a typical TM4SF protein complex, we raised monoclonal antibodies against proteins co-immunoprecipitated with CD81 from MDA-MB-435 breast cancer cells. Only two types of cell-surface proteins were recognized by our 35 selected antibodies. These included an integrin (alpha6beta1) and three different TM4SF proteins (CD9, CD63, and NAG-2). The protein NAG-2 (novel antigen-2) is a previously unknown 30-kDa cell-surface protein. Using an expression cloning protocol, cDNA encoding NAG-2 was isolated. When aligned with other TM4SF proteins, the deduced amino acid sequence of NAG-2 showed most identity (34%) to CD53. Flow cytometry, Northern blotting, and immunohistochemistry showed that NAG 2 is widely present in multiple tissues and cell types but is absent from brain, lymphoid cells, and platelets. Within various tissues, strongest staining was seen on fibroblasts, endothelial cells, follicular dendritic cells, and mesothelial cells. In nonstringent detergent, NAG-2 protein was co immunoprecipitated with other TM4SF members (CD9 and CD81) and integrins (alpha3beta1 and alpha6beta1). Also, two-color immunofluorescence showed that NAG 2 was co-localized with CD81 on the surface of spread HT1080 cells. These results confirm the presence of NAG-2 in specific TM4SF.TM4SF and TM4SF-integrin complexes. PMID- 9360997 TI - Elevations in cathepsin B protein content and enzyme activity occur independently of glycosylation during colorectal tumor progression. AB - Western blots, enzyme assays, protein glycosylation studies, and immunohistochemical staining were used to characterize cathepsin B expression at successive stages of colorectal tumor progression. In normal colon mucosa and premalignant adenomas, cathepsin B expression was predominantly due to mature two chain protein detected on Western blots as the nonglycosylated 27-kDa form, with overexpression of this protein occurring in only 4 of 18 adenomas. Overexpression increased significantly in Dukes A and B carcinomas (26 of 37 cases), with cathepsin B protein generally detectable in carcinomas as a combination of both 27-kDa nonglycosylated and 28-kDa glycosylated mature two-chain forms. Glycosylated cathepsin B protein in carcinoma extracts was sensitive to PNGase F but resistant to Endo H, indicating a pattern consistent with complex rather than high mannose type glycosylation. When sorted by advancing tumor stage, peak expression of cathepsin B protein occurred in carcinomas involved in local invasion compared with adenomas or metastatic cancers. At all stages, cathepsin B activity correlated significantly with the levels of heavy chain mature cathepsin B protein (r = 0.6682, p < 0.0001) irrespective of glycosylation. Immunohistochemical staining of cathepsin B protein revealed fine diffuse cytoplasmic staining in both adenomas and carcinomas compared with coarse granular cytoplasmic staining (typical of lysosomes) seen in matched normal mucosa. Our results demonstrate several sequential, apparently independent changes in cathepsin B expression during colorectal tumor progression including early changes in subcellular localization, up-regulation of cathepsin B protein and activity in invasive cancers, and altered protein glycosylation detected in malignant tumors at all stages. PMID- 9360998 TI - The coatomer protein beta'-COP, a selective binding protein (RACK) for protein kinase Cepsilon. AB - Distinct subcellular localization of activated protein kinase C (PKC) isozymes is mediated by their binding to isozyme-specific RACKs (receptors for activated C kinase). Our laboratory has previously isolated one such protein, RACK1, and demonstrated that this protein displays specificity for PKCbeta. We have recently shown that at least part of the PKCepsilon RACK-binding site on PKCepsilon lies within the unique V1 region of this isozyme (Johnson, J. A., Gray, M. O., Chen, C.-H., and Mochly-Rosen, D. (1996) J. Biol. Chem. 271, 24962-24966). Here, we have used the PKCepsilon V1 region to clone a PKCepsilon-selective RACK, which was identified as the COPI coatomer protein, beta'-COP. Similar to RACK1, beta' COP contains seven repeats of the WD40 motif and fulfills the criteria previously established for RACKs. Activated PKCepsilon colocalizes with beta'-COP in cardiac myocytes and binds to Golgi membranes in a beta'-COP-dependent manner. A role for PKC in control of secretion has been previously suggested, but this is the first report of direct protein/protein interaction of PKCepsilon with a protein involved in vesicular trafficking. PMID- 9360999 TI - CVT-313, a specific and potent inhibitor of CDK2 that prevents neointimal proliferation. AB - The activity of cyclin-dependent kinase 2 (CDK2) is essential for progression of cells from G1 to the S phase of the mammalian cell cycle. CVT-313 is a potent CDK2 inhibitor, which was identified from a purine analog library with an IC50 of 0.5 microM in vitro. Inhibition was competitive with respect to ATP (Ki = 95 nM), and selective CVT-313 had no effect on other, nonrelated ATP-dependent serine/threonine kinases. When added to CDK1 or CDK4, a 8.5- and 430-fold higher concentration of CVT-313 was required for half-maximal inhibition of the enzyme activity. In cells exposed to CVT-313, hyperphosphorylation of the retinoblastoma gene product was inhibited, and progression through the cell cycle was arrested at the G1/S boundary. The growth of mouse, rat, and human cells in culture was also inhibited by CVT-313 with the IC50 for growth arrest ranging from 1.25 to 20 microM. To evaluate the effects of CVT-313 in vivo, we tested this agent in a rat carotid artery model of restenosis. A brief intraluminal exposure of CVT-313 to a denuded rat carotid artery resulted in more than 80% inhibition of neointima formation. These observations suggest that CVT-313 is a promising candidate for evaluation in other disease models related to aberrant cell proliferation. PMID- 9361000 TI - Characterization of a novel, stage-specific, invariant surface protein in Trypanosoma brucei containing an internal, serine-rich, repetitive motif. AB - A new surface membrane protein, invariant surface glycoprotein termed ISG100, was identified in Trypanosoma brucei, using catalyzed surface, radioiodination of intact cells. This integral membrane glycoprotein was purified by a combination of detergent extraction, lectin-affinity, and ion-exchange chromatography followed by preparative SDS-polyacrylamide gel electrophoresis. The protein was expressed only in bloodstream forms of the parasite, was heavily N-glycosylated, and was present in different clonal variants of the same serodeme as well as in different serodemes. The gene for this protein was isolated by screening a cDNA expression library with antibodies against the purified protein followed by screening of a genomic library. The nucleotide sequence of the gene (4050 base pairs) predicted a highly reiterative polypeptide containing three distinct domains, a unique N-terminal domain of about 10 kDa containing three potential N glycosylation sites, which was followed by a large internal domain consisting entirely of 72 consecutive copies of a serine-rich, 17-amino acid motif (approximately 113 kDa) and terminated with an apparent transmembrane spanning region of about 3.3 kDa. The internal repeat region of this gene (3672 base pairs) represents the largest reiterative coding sequence to be fully characterized in any species of trypanosome. There was no significant homology with other known proteins, and overall the predicted protein was extremely hydrophobic. Unlike the genes for other surface proteins, the gene encoding ISG100 was present as a single copy. Although present in the flagellar pocket, ISG100 was predominantly associated with components of the pathways for endo/exocytosis, such as intracellular vesicles located in the proximity of the pocket as well a large, electron-lucent perinuclear digestive vacuole. PMID- 9361001 TI - The role of the nerve growth factor carboxyl terminus in receptor binding and conformational stability. AB - The role of the nerve growth factor (NGF) carboxyl terminus in the function of NGF is not well understood. Previous work showed that deletion of residues 112 120 abolished NGF bioactivity. Several mutagenesis studies, however, have localized the binding sites of the two NGF receptors, p75 and TrkA, to other regions of the NGF molecule. To investigate the role of the NGF COOH terminus, we performed a detailed structure-function analysis of this region by deleting stepwise each of the nine COOH-terminal residues as well as constructing six point mutants. We found that point mutations within the 111-115 region, but not deletion of residues 116-120, significantly decreased NGF bioactivity, as determined by TrkA tyrosine phosphorylation and neurite outgrowth from PC12 cells. Mutation of the absolutely conserved Leu112 led to severely disrupted p75 binding on A875 cells but had only a modest effect on TrkA binding to MG87-TrkA fibroblasts. This suggests that the p75 binding surface is more extended than previously believed and includes not only charged residues within loops 1 and 5 but also spatially discontinuous, uncharged residues in a region where the NH2 and COOH termini are in close proximity. Unexpectedly, deletion of COOH-terminal residues beyond Ala116 led to significantly decreased stability. These results demonstrate that residues 111-115, but not residues 116-120, are important for both the structural stability and biological activity of NGF. PMID- 9361002 TI - Expression of dopamine D3 receptor dimers and tetramers in brain and in transfected cells. AB - The expression and characteristics of the dopamine D3 receptor protein were studied in brain and in stably transfected GH3 cells. Monoclonal antibodies were used for immunoprecipitation and immunoblot experiments. Immunoprecipitates obtained from primate and rodent brain tissues contain a low molecular weight D3 protein and one or two larger protein species whose molecular mass are integral multiples of the low molecular weight protein and thus appear to have resulted from dimerization and tetramerization of a D3 monomer. Whereas D3 receptor multimers were found to be abundantly expressed in brain, the major D3 immunoreactivity expressed in stable D3-expressing rat GH3 cells was found to be a monomer. However, multimeric D3 receptor species with electrophoretic mobilities similar to those expressed in brain were also seen in D3-expressing GH3 cells when a truncated D3-like protein (named D3nf) was co-expressed in these cells. Furthermore, results from immunoprecipitation experiments with D3- and D3nf-specific antibodies show that the higher-order D3 proteins extracted from brain and D3/D3nf double transfectants also contain D3nf immunoreactivity, and immunocytochemical studies show that the expression of D3 and D3nf immunoreactivities overlaps substantially in monkey and rat cortical neurons. Altogether, these data show oligomeric D3 receptor protein expression in vivo and they suggest that at least some of these oligomers are heteroligomeric protein complexes containing D3 and the truncated D3nf protein. PMID- 9361003 TI - Dentatorubral pallidoluysian atrophy (DRPLA) protein is cleaved by caspase-3 during apoptosis. AB - Dentatorubral pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disorder. It is associated with an abnormal CAG repeat expansion resulting in formation of a protein with an elongated polyglutamine stretch. However, neither the physiological roles of the DRPLA gene product nor molecular mechanisms of its pathogenesis have yet been elucidated. Here we report that the DRPLA protein is cleaved at a site near the N terminus during apoptosis induced by VP-16, staurosporine, or glucocorticoid. Moreover, the in vitro translated DRPLA protein is cleaved by recombinant caspase-3, a member of the cysteine protease family, which is thought to be a main executioner of apoptosis. Using mutant DRPLA proteins, the cleavage site was identified as 106DSLDG110. The cleavage, however, was not modulated by the length of the polyglutamine stretch. These findings suggest that the DRPLA protein is one of the physiological substrates of caspase-3, and its cleavage may result in structural and biochemical alterations associated with apoptosis. PMID- 9361004 TI - The fundamental ribosomal RNA transcription initiation factor-IB (TIF-IB, SL1, factor D) binds to the rRNA core promoter primarily by minor groove contacts. AB - Acanthamoeba castellanii transcription initiation factor-IB (TIF-IB) is the TATA binding protein-containing transcription factor that binds the rRNA promoter to form the committed complex. Minor groove-specific drugs inhibit TIF-IB binding, with higher concentrations needed to disrupt preformed complexes because of drug exclusion by bound TIF-IB. TIF-IB/DNA interactions were mapped by hydroxyl radical and uranyl nitrate footprinting. TIF-IB contacts four minor grooves in its binding site. TIF-IB and DNA wrap around each other in a right-handed superhelix of high pitch, so the upstream and downstream contacts are on opposite faces of the helix. Dimethyl sulfate protection assays revealed limited contact with a few guanines in the major groove. This detailed analysis suggests significant DNA conformation dependence of the interaction. PMID- 9361005 TI - The smallest carbamoyl-phosphate synthetase. A single catalytic subdomain catalyzes all three partial reactions. AB - Escherichia coli carbamoyl-phosphate synthetase (CPSase) is comprised of a 40-kDa glutaminase (GLN) and a 120-kDa synthetase (CPS) subunit. The CPS subunit consists of two homologous domains, CPS.A and CPS.B, which catalyze the two different ATP-dependent partial reactions involved in carbamoyl phosphate synthesis. Sequence similarities and controlled proteolysis experiments suggest that the CPS subdomains consist, in turn, of three subdomains, designated A1, A2, A3 and B1, B2, B3 for CPS.A and CPS.B, respectively. Previous studies of individually cloned CPS.A and CPS. B from E. coli and mammalian CPSase have shown that homologous dimers of either of these "half-molecules" could catalyze all three reactions involved in ammonia-dependent carbamoyl phosphate synthesis. Four smaller recombinant proteins were made for this study as follows: 1) A1-A2 in which the A3 subdomain was deleted from CPS.A, 2) B1-B2 lacking subdomain B3 of CPS.B, 3) the A2 subdomain of CPS.A, and 4) the B2 subdomain of CPS.B. When associated with the GLN subunit, A1-A2 and B1-B2 had both glutamine- and ammonia dependent CPSase activities comparable to the wild-type protein. In contrast, the 27-kDa A2 and B2 recombinant proteins, which represent only 17% of the mass of the parent protein, were unable to use glutamine as a nitrogen donor, but the ammonia-dependent activity was enhanced 14-16-fold. The hyperactivity suggests that A2 and B2 are the catalytic subdomains and that A1 and B1 are attenuation domains which suppress the intrinsically high activity and are required for the physical association with the GLN subunit. PMID- 9361006 TI - Cloning and characterization of phospholipase D from rat brain. AB - The regulation of phospholipase D cloned from rat brain (rPLD) was examined in vivo and in vitro. The enzyme was a shorter splice variant of human phospholipase D 1 (Hammond, S. M., Altshuller, Y. M. , Sung, T.-C., Rudge, S. M., Rose, K., Engebrecht, J. A., Morris, A. J., and Frohman, M. A. (1995) J. Biol. Chem. 270, 29640-29643). Its expression in COS-7 cells led to increased phospholipase D (PLD) activity that was further stimulated by constitutively active V14RhoA. V14RhoA had no effect on the endogenous PLD of the COS-7 cells, but constitutively active L71ARF3 increased its activity. In contrast, L71ARF3 did not activate rPLD expressed in the cells. Addition of phorbol ester markedly increased the endogenous PLD activity of COS-7 cells, and there was a further increase in the cells expressing rPLD. In membranes from COS-7 cells expressing rPLD, addition of myristoylated ADP-ribosylation factor (ARF) and RhoA in vitro stimulated PLD activity. The effect of ARF was greater than that of RhoA, although the concentrations for half-maximal stimulation (0.08-0.2 microM) were similar. Membranes isolated from cells expressing rPLD plus L71ARF3 and/or V14RhoA also showed higher PLD activity but no synergism between the two G proteins. Addition of phorbol ester and protein kinase C alpha (PKCalpha) also stimulated PLD activity in membranes from COS-7 cells expressing rPLD, but it had no effect on the activity in control (vector) membranes and did not enhance the effects of constitutively active ARF or Rho. The stimulation by PKCalpha did not require ATP and was not increased by addition of this nucleotide. No synergism between ARF and Rho and between these and PKCalpha on PLD activity was observed when these were added to membranes from cells expressing rPLD. Oleate inhibited the PLD activity of membranes from both control and rPLD-expressing cells. In summary, these results indicate that in vitro, rPLD is stimulated by ARF, RhoA, and PKCalpha and inhibited by oleate. However, in intact COS-7 cells, ARF activates endogenous PLD but not rPLD, whereas the reverse is true for RhoA. In addition, the effects of phorbol ester are much greater in the intact cells. It is concluded that the regulation of rPLD in intact COS-7 cells differs significantly from that seen in vitro; possible reasons for this are discussed. PMID- 9361007 TI - Transactivation of an intronic hematopoietic-specific enhancer of the human Wilms' tumor 1 gene by GATA-1 and c-Myb. AB - The Wilms' tumor 1 gene (WT1) encodes a zinc-finger transcription factor which is expressed in a tissue-specific manner. Our studies indicate that in addition to the promoter, other regulatory elements are required for tissue-specific expression of this gene. A 258-base pair hematopoietic specific enhancer in intron 3 of the WT1 gene increased the transcriptional activity of the WT1 promoter by 8-10-fold in K562 and HL60 cells. Sequence analysis revealed both a GATA and a c-Myb motif in the enhancer fragment. Mutation of the GATA motif decreased the enhancer activity by 60% in K562 cells. Electrophoretic mobility shift assays showed that the GATA-1 protein in K562 nuclear extracts binds to this motif. Cotransfection of the enhancer containing reporter construct with a GATA-1 expression vector showed that GATA-1 transactivated this enhancer, increasing the CAT reporter activity 10-15-fold. Similar analysis of the c-Myb motif by cotransfection with the enhancer CAT reporter construct and a c-Myb expression vector showed that c-Myb transactivated the enhancer by 5-fold. A DNase I-hypersensitive site has also been mapped in the 258-base pair enhancer region. These data suggest that GATA-1 and c-Myb are responsible for the activity of this enhancer in hematopoietic cells and may bind to the enhancer in vivo. PMID- 9361008 TI - Interleukin-3 induces association of the protein-tyrosine phosphatase SHP2 and phosphatidylinositol 3-kinase with a 100-kDa tyrosine-phosphorylated protein in hemopoietic cells. AB - We have observed previously the co-immunoprecipitation of the p85 subunit of phosphatidylinositol-3 kinase (PI3K) and SHP2 in murine lymphohemopoietic cells after stimulation with interleukin-3. We have investigated this interaction in more detail and now report the identification of a potentially novel 100-kDa protein (termed p100), which is inducibly phosphorylated on tyrosine after interleukin-3 treatment and which co-immunoprecipitates with both p85 PI3K and SHP2. The Src homology region 2 domains of both p85 and SHP2 appear to mediate their interactions with p100. Sequential precipitation analyses suggest that these interactions are direct and do not involve Grb2, and that the same p100 protein, or a portion of it, interacts with both p85 and SHP2, implying that p100 may serve to link these two proteins. Far Western blotting with both full-length p85 and isolated p85 Src homology region 2 domains supports this view. Interestingly, p100 also appears to be a substrate for the SHP2 phosphatase activity. In addition, p100 is precipitated by Grb2-glutathione S-transferase fusion proteins, an interaction largely mediated by the Grb2 SH3 domains. p100 appears to be distinct from JAK2, Vav, STAT5, and c-Cbl. Although largely cytosolic, p100 can be detected associated with SHP2 and PI3K in crude membrane fractions after interleukin-3 stimulation. We propose that p100 plays a role as an adaptor molecule, linking PI3K and SHP2 in IL-3 signaling. PMID- 9361009 TI - Mechanisms of MARCKS gene activation during Xenopus development. AB - The myristoylated alanine-rich protein kinase C substrate (MARCKS) is a high affinity cellular substrate for protein kinase C. The MARCKS gene is under multiple modes of transcriptional control, including cytokine- and transformation dependent, cell-specific, and developmental regulation. This study evaluated the transcriptional control of MARCKS gene expression during early development of Xenopus laevis. Xenopus MARCKS was highly conserved with its mammalian and avian homologues; its mRNA and protein were abundant in the maternal pool and increased after the mid-blastula transition (MBT). The Xenopus MARCKS gene was similar to those of other species, except that a second intron interrupted the 5'- untranslated region. By transiently transfecting XTC-2 cells and microinjecting Xenopus embryos with reporter gene constructs containing serial deletions of 5' flanking MARCKS sequences, we identified a 124-base pair minimal promoter that was critical for promoter activity. Developmental gel shift assays revealed that a CBF/NF-Y/CP-1-like factor and an Sp1-like factor bound to this region in a manner correlating with the onset of Xenopus MARCKS transcription at MBT. Mutations in the promoter that abolished binding of these two factors also completely inhibited transcriptional activation of the MARCKS gene at MBT. The binding sites for these two factors are highly conserved in the human and mouse MARCKS promoters, suggesting that these elements might also regulate MARCKS transcription in other species. These studies not only increase our knowledge of the transcriptional regulation of the MARCKS genes but also have implications for the mechanisms responsible for zygotic activation of the Xenopus genome at MBT. PMID- 9361010 TI - Role of the tuberous sclerosis gene-2 product in cell cycle control. Loss of the tuberous sclerosis gene-2 induces quiescent cells to enter S phase. AB - Tuberous sclerosis is an autosomal dominant disorder characterized by the development of benign growths in many tissues and organs. Linkage analysis revealed two disease-determining genes on chromosome 9 and chromosome 16. The TSC2 gene on chromosome 16 encodes a 1784-amino acid tumor suppressor protein, tuberin, that functions as a GTPase-activating protein for Rap1, a member of the superfamily of Ras-related proteins. By immunoblot analyses, we found TSC2 expression to be high in G0 as well as in early small G1 cells. Analyses after different cell synchronization procedures revealed that TSC2 mRNA and protein expression do not fluctuate throughout the cell cycle. Using inducible expression systems we further demonstrated that TSC2 expression is not affected by overexpression of the mitogenic transcription factor E2F-1 or c-Myc. Nevertheless, antisense inhibition of tuberin expression in logarithmically growing cells markedly decreased the percentage of cells in G1. Furthermore, we found that cells exposed to TSC2 antisense oligonucleotides did not undergo G0 arrest after serum withdrawal. Antisense inhibition of TSC2 expression also induced quiescent G0-arrested fibroblasts to reenter the cell cycle. Our data show for the first time that the absence of tuberin can both induce cells to pass through the G1/S transition of the eukaryotic cell cycle and prevent them from entering a quiescent state. These results have clear implications for the tumor suppressor function of TSC2. We further found that reentry into the cell cycle upon loss of TSC2 is dependent on the activity of the G1 cyclin-dependent kinases (CDKs), Cdk2 or Cdk4. Taken together with our finding that antisense inhibition of TSC2 causes up-regulation of cyclin D1 expression, these results provide the first evidence for a connection between tuberin/Rap1 and the G1 CDK-dependent regulation of the transition from G0/G1 to S phase. PMID- 9361011 TI - Differentiation and transforming growth factor-beta receptor down-regulation by collagen-alpha2beta1 integrin interaction is mediated by focal adhesion kinase and its downstream signals in murine osteoblastic cells. AB - Interaction of type I collagen (COL(I)) with alpha2beta1 integrin causes differentiation and transforming growth factor (TGF)-beta receptor down regulation in osteoblastic cells (Takeuchi, Y., Nakayama, K., and Matsumoto, T. (1996) J. Biol. Chem. 271, 3938-3644). The TGF-beta receptor down-regulation enables cells to escape from the inhibition of differentiation by TGF-beta. To clarify how the cell-matrix interaction regulates these phenotypic changes, signaling pathways were examined in murine MC3T3-E1 cells. Attachment of cells to COL(I) stimulated tyrosine phosphorylation of focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK), a mitogen-activated protein kinase (MAPK), and enhanced MAPK activity. Inhibition of tyrosine kinase by herbimycin A, destruction of focal adhesion by cytochalasin D, or overexpression of antisense FAK mRNA prevented the activation of ERK/MAPK and the increase in alkaline phosphatase (ALP) activity. Transient expression of a MAPK-specific phosphatase, CL100, also suppressed the elevation of ALP activity. In addition, introduction of a constitutively active MAPK kinase enhanced ALP activity in the absence of collagen production. TGF-beta receptor down-regulation was abrogated by treatments that inactivate FAK, whereas the expression of CL100 had no effect. These results demonstrate that COL(I)-alpha2beta1 integrin interaction facilitates differentiation and down-regulates TGF-beta receptors via the activation of FAK and its diverse downstream signals. These signaling pathways may play an important role in the sequential differentiation of osteoblasts during bone formation. PMID- 9361012 TI - Antisense inhibition of group VI Ca2+-independent phospholipase A2 blocks phospholipid fatty acid remodeling in murine P388D1 macrophages. AB - A major issue in lipid signaling relates to the role of particular phospholipase A2 isoforms in mediating receptor-triggered responses. This has been difficult to study because of the lack of isoform-specific inhibitors. Based on the use of the Group VI Ca2+-independent phospholipase A2 (iPLA2) inhibitor bromoenol lactone (BEL), we previously suggested a role for the iPLA2 in mediating phospholipid fatty acid turnover (Balsinde, J., Bianco, I. D., Ackermann, E. J., Conde Frieboes, K., and Dennis, E. A. (1995) Proc. Natl. Acad. Sci. U. S. A. 92: 8527 8531). We have now further evaluated the role of the iPLA2 in phospholipid remodeling by using antisense RNA technology. We show herein that inhibition of iPLA2 expression by a specific antisense oligonucleotide decreases both the steady-state levels of lysophosphatidylcholine and the capacity of the cell to incorporate arachidonic acid into membrane phospholipids. These effects correlate with a decrease in both iPLA2 activity and protein in the antisense-treated cells. Collectively these data provide further evidence that the iPLA2 plays a major role in regulating phospholipid fatty acyl turnover in P388D1 macrophages. In stark contrast, experiments with activated cells confirmed that the iPLA2 does not play a significant role in receptor-coupled arachidonate mobilization in these cells, as manifested by the lack of an effect of the iPLA2 antisense oligonucleotide on PAF-stimulated arachidonate release. PMID- 9361013 TI - The noncatalytic C-terminal segment of the T cell protein tyrosine phosphatase regulates activity via an intramolecular mechanism. AB - Human T cell protein tyrosine phosphatase (TCPTP) is a nontransmembrane enzyme, the first of the protein tyrosine phosphatase family to be cloned. Alternative mRNA splicing results in variation in the sequence at the extreme C terminus of TCPTP and generates a 45-kDa form (TC45) that is targeted to the nucleus and a 48 kDa variant (TC48) associated with membranes of the endoplasmic reticulum. In this report, we assessed the role of the C-terminal, noncatalytic segment of TCPTP in regulating activity, concentrating primarily on the TC45 variant. We have demonstrated that limited tryptic proteolysis of TC45 releases first a 42 kDa fragment, then a 33-kDa catalytic domain. Using reduced carboxyamidomethylated and maleylated lysozyme as substrate (RCML), the catalytic domain displays 20-100-fold more activity than the full-length enzyme. Analysis of the time course of limited trypsinolysis revealed that proteolytic activation occurred following cleavage of a protease-sensitive region (residues 353-387) located at the C terminus of TC45. The activity of truncation mutants illustrated that removal of 20 C-terminal residues was sufficient to activate the enzyme fully. The 33-kDa catalytic domain, but not the full-length enzyme, was inhibited in a concentration-dependent manner by addition of the noncatalytic C-terminal segment of TC45. A monoclonal antibody to TCPTP, CF4, which recognizes an epitope located between residues 350 and 363, was capable of fully activating TC45. These data indicate that the noncatalytic segment of TC45 contains an autoregulatory site that modulates activity via a reversible intramolecular interaction with the catalytic domain. These studies suggest that the C-terminal noncatalytic segment of TC45, and possibly TC48, may not only direct the enzyme to different subcellular locations but may also modulate activity in response to the binding of regulatory proteins and/or posttranslational modification. PMID- 9361014 TI - The laminin alpha2-chain short arm mediates cell adhesion through both the alpha1beta1 and alpha2beta1 integrins. AB - Laminin-2, a heterotrimer composed of alpha2, beta1, and gamma1 subunits, is the primary laminin isoform found in muscle and peripheral nerve and is essential for the development and stability of basement membranes in these tissues. Expression of a domain VI-truncated laminin alpha2-chain results in muscle degeneration and peripheral nerve dysmyelination in the dy2J dystrophic mouse. We have expressed amino-terminal domains VI through IVb of the laminin alpha2-chain, as well as its laminin-1 alpha1-chain counterpart, to identify candidate cell-interactive functions of this critical region. Using integrin-specific antibodies, recognition sites for the alpha1beta1 and alpha2beta1 integrins were identified in the short arms of both laminin alpha1- and alpha2-chain isoforms. Comparisons with a beta-alpha chimeric short arm protein possessing beta1-chain domain VI further localized these activities to alpha-chain domain VI. In addition, we found that the laminin alpha2-chain short arm supported neurite outgrowth independent of other laminin-2 subunits. A heparin/heparan sulfate binding activity was also localized to this region of the laminin alpha2 subunit. These data provide the first evidence that domain VI of the laminin alpha2-chain mediates interactions with cell surface receptors and suggest that these integrin and heparin binding sites, alone or in concert, may play an important role in muscle and peripheral nerve function. PMID- 9361015 TI - Cell-type and tissue-specific expression of caveolin-2. Caveolins 1 and 2 co localize and form a stable hetero-oligomeric complex in vivo. AB - Caveolae are microdomains of the plasma membrane that have been implicated in organizing and compartmentalizing signal transducing molecules. Caveolin, a 21-24 kDa integral membrane protein, is a principal structural component of caveolae membrane in vivo. Recently, we and other laboratories have identified a family of caveolin-related proteins; caveolin has been re-termed caveolin-1. Here, we examine the cell-type and tissue-specific expression of caveolin-2. For this purpose, we generated a novel mono-specific monoclonal antibody probe that recognizes only caveolin-2, but not caveolins-1 and -3. A survey of cell and tissue types demonstrates that the caveolin-2 protein is most abundantly expressed in endothelial cells, smooth muscle cells, skeletal myoblasts (L6, BC3H1, C2C12), fibroblasts, and 3T3-L1 cells differentiated to adipocytes. This pattern of caveolin-2 protein expression most closely resembles the cellular distribution of caveolin-1. In line with these observations, co immunoprecipitation experiments with mono-specific antibodies directed against either caveolin-1 or caveolin-2 directly show that these molecules form a stable hetero-oligomeric complex. The in vivo relevance of this complex was further revealed by dual-labeling studies employing confocal laser scanning fluorescence microscopy. Our results indicate that caveolins 1 and 2 are strictly co-localized within the plasma membrane and other internal cellular membranes. Ultrastructurally, this pattern of caveolin-2 localization corresponds to caveolae membranes as seen by immunoelectron microscopy. Despite this strict co localization, it appears that regulation of caveolin-2 expression occurs independently of the expression of either caveolin-1 or caveolin-3 as observed using two different model cell systems. Although caveolin-1 expression is down regulated in response to oncogenic transformation of NIH 3T3 cells, caveolin-2 protein levels remain unchanged. Also, caveolin-2 protein levels remain unchanged during the differentiation of C2C12 cells from myoblasts to myotubes, while caveolin-3 levels are dramatically induced by this process. These results suggest that expression levels of caveolins 1, 2, and 3 can be independently up-regulated or down-regulated in response to a variety of distinct cellular cues. PMID- 9361016 TI - Bcl-2 counters apoptosis by Bax heterodimerization-dependent and -independent mechanisms in the T-cell lineage. AB - The effect of the cell death inhibitor Bcl-2 in relation to its capacity to dimerize with apoptosis promoter Bax or its homologs at their physiological expression levels was explored in the T-cell lineage. Transgenic mice expressing a BH1 mutant Bcl-2 (Bcl-2 mI-3), which fails to heterodimerize with proapoptotic members of the Bcl-2 family, such as Bax, were generated. Bcl-2 mI-3 protected immature CD4+8- thymocytes from spontaneous, glucocorticoid and anti-CD3-induced apoptosis and altered T cell maturation, resulting in increased percentages of CD3(hi) and CD4-8+ thymocytes. In contrast, apoptosis of peripheral T-cells was unaffected by transgene expression. This correlated with their high Bax expression level and insensitivity to the caspase inhibitor, zVAD-fmk, a functional hallmark of Bax-like activity. Thus, within the T-cell lineage Bcl-2 can inhibit apoptosis independent of its association with Bax or its homologs; yet, above a threshold level of their physiologic proapoptotic activity, the capacity of Bcl-2 to heterodimerize with Bax or its homologs appears essential for it to counter cell death. PMID- 9361017 TI - Molecular cloning and expression of rat liver endo-alpha-mannosidase, an N-linked oligosaccharide processing enzyme. AB - A clone containing the open reading frame of endo-alpha-D-mannosidase, an enzyme involved in early N-linked oligosaccharide processing, has been isolated from a rat liver lambdagt11 cDNA library. This was accomplished by a strategy that involved purification of the endomannosidase from rat liver Golgi by ligand affinity chromatography (Hiraizumi, S., Spohr, U., and Spiro, R. G. (1994) J. Biol. Chem. 269, 4697-4700) and preparative electrophoresis, followed by sequence determinations of tryptic peptides. Using degenerate primers based on these sequences, the polymerase chain reaction with rat liver cDNA as a template yielded a 470-base pair product suitable for library screening as well as Northern blot hybridization. EcoRI digestion of the purified lambda DNA released a 5.4-kilobase fragment that was amplified in Bluescript II SK(-) vector. Sequence analysis indicated that the deduced open reading frame of the endomannosidase extended from nucleotides 89 to 1441, encoding a protein of 451 amino acids and corresponding to a molecular mass of 52 kDa. Data base searches revealed no homology with any other known protein. When a vector coding for this protein fused to an NH2-terminal peptide containing a polyhistidine region was introduced into Escherichia coli, high levels of the enzyme were expressed upon induction with isopropyl-beta-D-thiogalactoside. Purification of the endomannosidase to electrophoretic homogeneity from E. coli lysates was accomplished by Ni2+-chelate and Glcalpha1-->3Man-O-(CH2)8CONH-Affi-Gel ligand chromatographies. Polyclonal antibodies raised against this protein reacted with Golgi endomannosidase. By both immunoblotting and silver staining, the purified E. coli-expressed enzyme was approximately 8 kDa smaller than anticipated from the open reading frame; timed induction studies indicated that this was due to scission of the enzyme's COOH-terminal end by host cell proteases. All rat tissues examined demonstrated mRNA levels (4.9-kilobase message) for the endomannosidase that correlated well with their enzyme activity. PMID- 9361018 TI - Cloning and characterization of the human selenoprotein P promoter. Response of selenoprotein P expression to cytokines in liver cells. AB - We isolated an 18-kilobase (kb) genomic selenoprotein P clone from a human placenta library and cloned, sequenced, and characterized the 5'-flanking region of the human selenoprotein P gene. Sequence analysis revealed an intron between base pairs (bp) -13 and -14 upstream of the ATG codon and another one between bp 534 and 535 of the coding region. The major transcription start site of selenoprotein P in human HepG2 hepatocarcinoma cells was mapped to bp -70 by 5' rapid amplification of cDNA ends and by primer extension. 1.8 kb of the 5' flanking sequence were fused to a luciferase reporter gene. They exhibited functional promoter activity in HepG2 hepatocarcinoma and Caco2 colon carcinoma cells in transient transfection experiments. Treatment of transfected HepG2 cells with the cytokines interleukin 1beta, tumor necrosis factor alpha, and interferon gamma repressed promoter activity. Nuclear extracts of interferon gamma-treated cells bound to a signal transducer and activator of transcription response element of the promoter in gel retardation experiments. By transfection of promoter-deletion constructs, a TATA box and a putative SP1 site were identified to be necessary for selenoprotein P transcription. These data indicate that the human selenoprotein P gene contains a strong promoter that is cytokine responsive. Furthermore, selenoprotein P, secreted by the liver, might react as a negative acute phase protein. PMID- 9361019 TI - Activation of the Ste20-like oxidant stress response kinase-1 during the initial stages of chemical anoxia-induced necrotic cell death. Requirement for dual inputs of oxidant stress and increased cytosolic [Ca2+]. AB - Signal transduction mechanisms activated during the early stages of necrotic cell death are poorly characterized. We have recently identified the Sterile 20 (Ste20)-like oxidant stress response kinase-1, SOK-1, which is a member of the Ste20 kinase family. We report that SOK-1 is markedly activated as early as 20 min after chemical anoxia induced by exposure of Madin-Darby canine kidney or LLC PK1 renal tubular epithelial cells to 2-deoxyglucose (2-DG) and any one of three inhibitors of the electron transport chain, cyanide (CN), rotenone, or antimycin A. Since oxidant stress activates SOK-1, we postulated that reactive oxygen species (ROS), which are produced by the electron transport chain during chemical anoxia, might be responsible for SOK-1 activation. The time course of CN/2-DG induced SOK-1 activation and of production of ROS, measured in cells loaded with dichlorofluorescein, were compatible with a role for ROS in SOK-1 activation. Furthermore, preincubation of LLC-PK1 cells with three unrelated scavengers of ROS, pyrrolidine dithiocarbamate, pyruvate, or nordihydroguaiaretic acid, reduced both cellular oxidant stress and activation of SOK-1 by CN/2-DG. An increase in cytosolic free [Ca2+] ([Ca2+]i) was necessary but not sufficient for CN/2-DG induced activation of SOK-1. Preincubation of cells with BAPTA-AM prevented activation of SOK-1. Incubation of cells with thapsigargin or the calcium ionophore, A23187, had no effect on SOK-1 activity, but preincubation of cells with either of these agents markedly enhanced CN/2-DG-induced activation of SOK-1 (20-fold versus 7-fold). In summary, chemical anoxia activates SOK-1 via an oxidant stress-dependent mechanism that is both critically dependent upon and markedly amplified by an increase in [Ca2+]i. This requirement for dual inputs of oxidant stress and an increase in [Ca2+]i may prevent inappropriate activation of the kinase by milder degrees of oxidant stress, which are insufficient to generate an increase in [Ca2+]i. The activation of SOK-1 may be one of the cell's earliest responses to inducers of necrotic cell death. PMID- 9361020 TI - The alphavbeta3 integrin regulates alpha5beta1-mediated cell migration toward fibronectin. AB - This study examines the interactions of alphavbeta3 and alpha5beta1 in the regulation of cell migration. Human embryonic kidney (HEK) 293 cells that express alpha5beta1 endogenously were transfected with alphavbeta3 and beta3 mutants, and their attachment and migration to fibronectin (Fn) and vitronectin (Vn) were measured. An alphavbeta3 blocking antibody and the alphavbeta3 ligand cyclic G Pen-GRGDSPC-A inhibited alpha5beta1-mediated migration toward Fn, but not attachment to Fn. This function was alphavbeta3-specific since alphavbeta5 transfection and alphavbeta5 blocking antibody did not produce this effect. Mutations introduced into the beta3 integrin subunit to dissect this phenomenon revealed the following. Disruption of the ligand binding domain by the Glanzmann thrombasthenia mutation beta3-D119Y constitutively abolished migration toward both Vn and Fn, and attachment to Vn but not to Fn. Insertion of the Glanzmann mutation beta3-S752P into the cytoplasmic domain or its truncation (beta3 Delta717) abolished binding to Vn but not to Fn. Inhibition of migration toward Fn was inhibited in these cells by alphavbeta3 blocking antibody. alphavbeta3 mediated inhibition was, however, abolished by truncation of the transmembrane domain (beta3-Delta693). These findings demonstrate alphavbeta3 regulation of alpha5beta1-mediated cell migration and suggest that the beta3 transmembrane domain is essential for this function. PMID- 9361021 TI - Slow degradation of aggregates of the Alzheimer's disease amyloid beta-protein by microglial cells. AB - Microglia are immune system cells associated with senile plaques containing beta amyloid (Abeta) in Alzheimer's disease. Although microglia are an integral part of senile plaques, their role in the development of Alzheimer's disease is not known. Because microglia are phagocytic cells, it has been suggested that microglia may function as plaque-attacking scavenger cells. Microglia bind and internalize microaggregates of Abeta that resemble those present in dense Alzheimer's disease plaques. In this study, we compared the degradation by microglia of Abeta microaggregates with the degradation of two other proteins, acetylated low density lipoprotein and alpha2-macroglobulin. We found that the majority of the internalized Abeta in microaggregates was undegraded 72 h after uptake, whereas 70-80% of internalized acetylated low density lipoprotein or alpha2-macroglobulin was degraded and released from cells in trichloroacetic acid soluble form after 4 h. In the continued presence of fluorescent Abeta microaggregates for 4 days, microglia took up huge amounts of Abeta and became engorged with undigested material. These data suggest that microglia can slowly degrade limited amounts of Abeta plaque material, but the degradation mechanisms can be overwhelmed by larger amounts of Abeta. PMID- 9361022 TI - Towards an ovine model of cystic fibrosis. PMID- 9361023 TI - Dp260 disrupted mice revealed prolonged implicit time of the b-wave in ERG and loss of accumulation of beta-dystroglycan in the outer plexiform layer of the retina. AB - Dp260 is a C-terminal isoform of dystrophin and is expressed specifically in the retina. Abnormal electroretinograms (ERG) in some Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) patients are likely linked to a disruption of Dp260. To clarify the importance of Dp260 in the retina, we examined dystrophin exon 52 knock-out mice, whose expression of Dp260 is impaired. We also confirmed the localization of Dp260 in the outer plexiform layer (OPL) of the retina. Disruption of Dp260 causes a change in the localization of beta-dystroglycan, which is normally found in the OPL of the retina. This suggests a requirement for Dp260 for normal formation of the dystrophin-dystroglycan complex in the retina. Dp71, also expressed in the retina, was, however, not detected in the OPL. The difference in localization of Dp260 and Dp71 implies that the two isoforms have different functions. The dystrophin exon 52 knock-out mice had a prolonged implicit time of the b-wave in ERG, although no significant change was observed in amplitude. These ERG findings differed from those of DMD and BMD patients, especially with regard to amplitude of the b-wave, but make it clear that Dp260 is required for normal electrophysiology. PMID- 9361024 TI - Huntingtin-associated protein 1 (HAP1) interacts with the p150Glued subunit of dynactin. AB - Huntington's disease (HD) is an inherited neurodegenerative disease caused by expansion of a polyglutamine repeat in the HD protein huntingtin. Huntingtin's localization within the cell includes an association with cytoskeletal elements and vesicles. We previously identified a protein (HAP1) which binds to huntingtin in a glutamine repeat length-dependent manner. We now report that HAP1 interacts with cytoskeletal proteins, namely the p150 Glued subunit of dynactin and the pericentriolar protein PCM-1. Structural predictions indicate that both HAP1 and the interacting proteins have a high probability of forming coiled coils. We examined the interaction of HAP1 with p150 Glued . Binding of HAP1 to p150 Glued (amino acids 879-1150) was confirmed in vitro by binding of p150 Glued to a HAP1 GST fusion protein immobilized on glutathione-Sepharose beads. Also, HAP1 co immunoprecipitated with p150 Glued from brain extracts, indicating that the interaction occurs in vivo . Like HAP1, p150 Glued is highly expressed in neurons in brain and both proteins are enriched in a nerve terminal vesicle-rich fraction. Double label immunofluorescence experiments in NGF-treated PC12 cells using confocal microscopy revealed that HAP1 and p150 Glued partially co localize. These results suggest that HAP1 might function as an adaptor protein using coiled coils to mediate interactions among cytoskeletal, vesicular and motor proteins. Thus, HAP1 and huntingtin may play a role in vesicle trafficking within the cell and disruption of this function could contribute to the neuronal dysfunction and death seen in HD. PMID- 9361025 TI - Functional modeling of vitamin responsiveness in yeast: a common pyridoxine responsive cystathionine beta-synthase mutation in homocystinuria. AB - Cystathionine beta-synthase (CBS) deficiency is an autosomal recessive disorder which results in extremely elevated levels of total plasma homocysteine (tHcy) and high risk of thromboembolic events. About half of all patients diagnosed with CBS deficiency respond to pyridoxine treatment with a significant lowering of tHcy levels. We examined 12 CBS-deficient patients from 10 Norwegian families for mutations in the CBS gene and identified mutations in 18 of the 20 CBS alleles. Five of the seven patients classified as pyridoxine-responsive contain the newly identified point mutation, G797A (R266K). This point mutation is tightly linked with a previously identified 'benign' 68 bp duplication of the intron 7-exon 8 boundary within the CBS gene. We tested the effect of all of the mutations identified on human CBS function utilizing a yeast system. Five of the six mutations had a distinguishable phenotype in yeast, indicating that they were in fact pathogenic. Interestingly, the G797A allele had no phenotype when the yeast were grown in high concentrations of pyridoxine, but a severe phenotype when grown in low concentrations, thus mirroring the behavior in humans. These studies show that the G797A mutation is an important cause of pyridoxine-responsive CBS deficiency and demonstrate the utility of yeast functional assays in the analysis of human mutations. PMID- 9361026 TI - Activation of the human transglutaminase 1 promoter in transgenic mice: terminal differentiation-specific expression of the TGM1-lacZ transgene in keratinized stratified squamous epithelia. AB - Transglutaminase 1 (TGase 1) is a tissue-specific enzyme which is expressed in the keratinized stratified squamous epithelia and which catalyzes straightepsilon (gamma-glutamyl) lysine cross-links of proteins to form the cell envelope at the periphery of cornified cells. A transient expression assay using a luciferase reporter gene linked to the 2.5 kb 5' upstream region of the human TGase 1 gene (TGM1) showed phorbol ester-responsive promoter activity in cultured normal human keratinocytes. To assess its promoter activity in vivo, we generated transgenic mice expressing the Escherichia coli beta-galactosidase gene (lacZ) directed by the 5' upstream region. beta-Galactosidase histochemistry revealed that the TGM1 lacZ transgene was expressed in terminally differentiating keratinocytes in upper layers of stratified squamous epithelia in embryonic, neonatal and adult transgenic mice. The expression pattern was similar to that of endogenous TGase 1 mRNA detected by in situ hybridization. Furthermore, topical application of a phorbol ester to adult tail skin enhanced expression of the transgene as well as TGase 1 mRNA in the epidermis. Thus, the 2.5 kb 5' upstream sequence of TGM1 includes elements regulating tissue- and terminal differentiation-specific gene expression in stratified squamous epithelia. PMID- 9361027 TI - Serotonin transporter (5-HTT) gene variants associated with autism? AB - An association study was performed to elucidate the role of the serotonin transporter (5-HTT) gene as a susceptibility factor for autism as treatment of patients with antidepressant drugs which selectively target 5-HTT reduced autistic or concomitant symptoms, such as repetitive behavior and aggression, and ameliorate language use. Using the transmission/disequilibrium test (TDT) an analysis was done for a common polymorphism in the upstream regulatory region (5 HTTLPR), a VNTR in intron 2 of the gene and a haplotype of both loci in 52 trios fulfilling stringent criteria for autism and an extended group of 65 trios including patients showing no language delay in their first 3 years of life. A higher frequency and preferential transmission of the long allele of the 5-HTTLPR was observed, but the TDT gave a statistically significant value ( P = 0. 032) only for the extended patient group. This result is in contrast to a recent study by a US group presenting preliminary evidence for preferential transmission of the short allele of 5-HTTLPR in 86 trios. Both studies failed to reveal significant linkage disequilibrium between the VNTR in intron 2 of the gene and autism. In our study haplotype analysis of the 5-HTTLPR and the VNTR in intron 2 supplied evidence for an association of 5-HTT and autism in the stringent ( P = 0.069) and extended patient group ( P = 0.049). Overall, we were not able to replicate the findings of the first study on 5-HTT and autism and instead observed a tendency for association of the opposite genetic variant of the gene with the disorder. The implications for genetic variants of the serotonin transporter in the etiology of autism and possible subgroups of patients, therefore, needs clarification in further studies with other and larger patient samples. PMID- 9361028 TI - Complete restoration of a wild-type mtDNA genotype in regenerating muscle fibres in a patient with a tRNA point mutation and mitochondrial encephalomyopathy. AB - Replicative segregation of mitochondrial DNA (mtDNA) can produce large differences in the proportions of wild-type and mutant mtDNAs in different cell types of patients with mitochondrial encephalomyopathy. This is particularly striking in the skeletal muscle of patients with Kearns-Sayre syndrome (KSS), a sporadic disease associated with large-scale mtDNA deletions, and in sporadic patients with tRNA point mutations. Although the skeletal muscle fibres of these patients invariably contain a large proportion of mutant mtDNAs, mutant mtDNAs are rare or undetectable in satellite cells cultured from the same muscle biopsy specimens. Since satellite cells are responsible for muscle fibre regeneration, restoration of the wild-type mtDNA genotype might be achieved in these patients by encouraging muscle regeneration. To test this concept, we re-biopsied a patient with a KSS phenotype and a mtDNA point mutation in the tRNAleu(CUN)gene and analysed muscle fibres regenerating at the site of the original muscle biopsy. Regenerating fibres were identified by morphological criteria and by expression of neural cell adhesion molecule (NCAM). All such fibers were positive for cytochrome c oxidase (COX) activity by cytochemistry and essentially homoplasmic for wild-type mtDNA, while the majority of non-regenerating fibres were COX-negative and contained predominantly mutant mtDNAs. These results demonstrate that it may be possible to improve muscle function in similar patients by methods that promote satellite cell incorporation into existing myofibres. PMID- 9361029 TI - Paternal expression of WT1 in human fibroblasts and lymphocytes. AB - The Wilms' tumor suppressor gene ( WT1 ) was previously identified as being imprinted, with frequent maternal expression in human placentae and fetal brains. We examined the allele-specific expression of WT1 in cultured human fibroblasts from 15 individuals. Seven of 15 fibroblast lines were heterozygous for polymorphic alleles, and the expression patterns were variable, i.e., equal, unequal or monoallelic paternal expression in three, two and two cases, respectively. Exclusive paternal expression of WT1 was also shown in non-cultured peripheral lymphocytes from the latter two individuals. The allele-specific expression profiles of other imprinted genes, IGF2 and H19, on human chromosome 11 were constant and consistent with those in other tissues. Our unexpected observations of paternal or biallelic expression of WT1 in fibroblasts and lymphocytes, together with the previous findings of maternal or biallelic expression in placentae and brains, suggest that the allele-specific regulatory system of WT1 is unique and may be controlled by a putative tissue- and individual-specific modifier. PMID- 9361030 TI - Clustering of mutations responsible for branchio-oto-renal (BOR) syndrome in the eyes absent homologous region (eyaHR) of EYA1. AB - Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder, characterised by the association of branchial, otic and renal anomalies with variable degrees of severity. We have recently identified EYA1 , a human homologue of the Drosophila eyes absent gene, as the gene underlying this syndrome. The products of both genes share a highly conserved 271 amino acid C terminal region (eyaHR). The eyaHR was also found in the products of two other human genes (EYA2 and EYA3), demonstrating the existence of a novel gene family. We report here on the complete genomic structure of EYA1. This gene consists of 16 coding exons and extends over 156 kb. It encodes various alternatively spliced transcripts differing only in their 5' regions. Sequence analysis of the entire EYA1 coding region was performed for 20 unrelated patients affected by BOR syndrome, and six novel mutations were identified. Among these mutations, two are missense mutations, highlighting amino acid residues essential for the function of the EYA1 protein, and one mutation comprises a de novo Alu insertion into an exon. This insertion presumably occurs by retrotransposition, and the mobile Alu element has a poly(A) tail that is unstable throughout generations. To date, 14 mutations have been detected in BOR patients, all of which are different. However, all the mutations are located within or in the immediate vicinity of the eyaHR; the significance of this clustering is discussed. PMID- 9361031 TI - Heart-specific localization of emerin: new insights into Emery-Dreifuss muscular dystrophy. AB - Emery-Dreifuss muscular dystrophy (EDMD) is an X-linked inherited disease characterized by early contracture of the elbows, Achilles tendons and post cervical muscles, slow progressive muscle wasting and weakness and cardiomyopathy presenting with arrhythmia and atrial paralysis: heart block can eventually lead to sudden death. The EDMD geneencodes a novel ubiquitous protein, emerin, which decorates the nuclear rim of many cell types. Amino acid sequence homology and cellular localization suggested that emerin is a member of the nuclear lamina associated protein family. These findings did not explain the role of emerin nor account for the skeletal muscle- and heart-specific clinical manifestations associated with the disorder. Now we report that emerin localizes to the inner nuclear membrane, via its hydrophobic C-terminal domain, but that in heart and cultured cardiomyocytes it is also associated with the intercalated discs. We propose a general role for emerin in membrane anchorage to the cytoskeleton. In the nuclear envelope emerin plays a ubiquitous and dispensable role in association of the nuclear membrane with the lamina. In heart its specific localization to desmosomes and fasciae adherentes could account for the characteristic conduction defects described in patients. PMID- 9361032 TI - Female germline mosaicism in tuberous sclerosis confirmed by molecular genetic analysis. AB - We have investigated a family in which three siblings with the autosomal dominant disorder tuberous sclerosis had unaffected parents. The family were typed for polymorphic markers spanning the two genes known to cause tuberous sclerosis located at 9q34 (TSC1) and 16p13.3 (TSC2). TSC1 markers showed different maternal and paternal haplotypes in affected children, excluding a mutation in TSC1 as the cause of the disease. For the TSC2 markers all the affected children had the same maternal and paternal haplotypes, as did three of their unaffected siblings. Mutation screening by RT-PCR and direct sequencing of the TSC2 gene identified a 4 bp insertion TACT following nucleotide 2077 in exon 18 which was present in the three affected children but not in five unaffected siblings or the parents. This mutation would cause a frameshift and premature termination at codon 703. Absence of the mutation in lymphocyte DNA from the parents was consistent with germline mosaicism and this was confirmed by our finding of identical chromosome 16 haplotypes in affected and unaffected siblings, providing unequivocal evidence of two different cell lines in the gametes. Molecular analysis of the TSC2 alleles present in the affected subjects showed that the mutation had been inherited from the mother. This is the first case of germline mosaicism in tuberous sclerosis proven by molecular genetic analysis and also the first example of female germline mosaicism for a characterized autosomal dominant gene mutation apparently not associated with somatic mosaicism. PMID- 9361033 TI - An adenosine deaminase (ADA) allele contains two newly identified deleterious mutations (Y97C and L106V) that interact to abolish enzyme activity. AB - Genetic deficiency of the purine salvage enzyme adenosine deaminase (ADA) results in varying degrees of immunodeficiency, ranging from neonatal onset Severe Combined Immunodeficiency (SCID) to an adult onset immunodeficiency disorder. Multiple different mutations have now been identified in these immunodeficient patients. Additional mutations, initially identified in healthy individuals, abolish ADA in erythrocytes but retain 10-80% of activity in non-erythroid cells ('partial deficiency mutations'). In general, severity of disease correlates inversely with the amount of residual ADA expressed by the mutant enzymes and directly with the accumulation of the toxic metabolites deoxyATP and deoxyadenosine. We report two newly identified mutations (Y97C and L106V), both carried on the same allele of an immunodeficient patient who was diagnosed prenatally and successfully transplanted with haploidentical bone marrow. Based on the ability of mutant cDNAs to express ADA in vitro , the L106V mutation resulted in activity similar to 'partial' mutations (30% of normal) while the Y97C mutation resulted in detectable but markedly reduced activity (1.5% of normal). However, the presence of both mutations on the same allele virtually abolished detectable enzyme activity. Analysis of the crystallographic structure of ADA to understand the marked deleterious effect of the Y97C mutation suggested a previously unappreciated role of salt bridges in the catalytic mechanism of ADA. The patient was also heteroallelic for a previously described deletion of the promoter and exon 1. Testing of additional patients in whom we had not identified a mutation on the second allele revealed presence of this deletion in three of four patients tested. This deletion is therefore relatively common, accounting for 10% of almost 100 chromosomes studied by this and other laboratories, but is easily missed by currently used methods of mutation detection. Lastly, the finding of two mutations on the same allele that interact to reduce residual enzyme function emphasizes hazards in evaluating potential genotype-phenotype correlations in individuals analyzed only for the presence of single specific mutations. PMID- 9361034 TI - Genetic linkage of the tricho-dento-osseous syndrome to chromosome 17q21. AB - Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a highly penetrant autosomal dominant trait that is characterized by variable clinical expression. The principal clinical features include kinky/curly hair in infancy, enamel hypoplasia, taurodontism, as well as increased thickness and density of cranial bones. Possible genetic linkage has been reported for TDO with the ABO blood group locus, but the gene defect remains unknown. We have identified four multiplex families (n = 63, 39 affected, 24 unaffected) from North Carolina segregating TDO. We previously have excluded a major locus for TDO in the ABO region for these families. Utilizing a genome-wide search strategy, we obtained conclusive evidence for linkage of the TDO syndrome locus to markers on chromosome 17q21 (D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7 cM chromosomal segment flanked by D17S932 and D17S941. This finding represents the first step towards isolation and cloning of the TDO gene. Identification of this gene has important implications for understanding normal and abnormal craniofacial development of hair, teeth and bone. PMID- 9361035 TI - Identification of MEN1 gene mutations in sporadic carcinoid tumors of the lung. AB - Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors. PMID- 9361036 TI - Sequences from higher primates orthologous to the human Xp/Yp telomere junction region reveal gross rearrangements and high levels of divergence. AB - A high level of sequence polymorphism combined with linkage disequilibrium has created a limited number of highly diverged haplotypes across the human Xp/Yp telomere junction region. To gain insight into the unusual genetic characteristics of this region, we have examined the orthologous sequences in the common chimpanzee (Pan troglodytes ), the gorilla (Gorilla gorilla) and the orang utan (Pongo pygmaeus). Divergence from the human Xp/Yp sequence is higher (average 2.6-fold) than that observed at other loci. The position of the human Xp/Yp telomere is unique, as additional sequences are present at this location in the other three species. These included an array of subterminal satellite in the chimpanzee and, in the gorilla a small interstitial array of telomere-like repeats followed by sequences with strong homology to the human 18p subterminal region. In the orang-utan, two alleles with different structures were identified. These differ by the presence or absence of a short interspersed nuclear element (SINE) sequence just proximal to long arrays of telomere-like repeat sequences that probably represent the proximal end of the orang-utan Xp/Yp telomere. In addition, a high level of sequence divergence between the two orang-utan structures was identified. This divergence is similar to that observed between the human Xp/Yp telomere-adjacent haplotypes. The high sequence divergence and evidence of gross rearrangements indicate that the Xp/Yp telomeric region has evolved faster than the rest of the genome. PMID- 9361037 TI - Efficient conditional mutation of the vertebrate CENP-C gene. AB - We have used gene targeting in the DT40 cell line to create a cell line which expresses a fusion between CENP-C and a mouse steroid receptor and which behaves as a conditional loss of function mutant of CENP-C. Under restrictive conditions these cells arrest at the metaphase/anaphase junction and after a delay of approximately 2.5 h die by apoptosis. These results indicate that CENP-C is either necessary for anaphase chromosome movement or for mediating a signal which triggers centromere function during anaphase. Our approach is simple and applicable to a wide range of proteins with general cell autonomous functions in vertebrates. PMID- 9361038 TI - Low proportion of BRCA1 and BRCA2 mutations in Finnish breast cancer families: evidence for additional susceptibility genes. AB - One hundred breast and breast-ovarian cancer families identified at the Helsinki University Central Hospital in southern Finland and previously screened for mutations in the BRCA2 gene were now analyzed for mutations in the BRCA1 gene. The coding region and splice boundaries of BRCA1 were analyzed by protein truncation test (PTT) and heteroduplex analysis (HA)/SSCP in all 100 families, and 70 were also screened by direct sequencing. Contrary to expectations based on Finnish population history and strong founder effects in several monogenic diseases in Finland, a wide spectrum of BRCA1 and BRCA2 mutations was found. In the BRCA1 gene, 10 different protein truncating mutations were found each in one family. Six of these are novel Finnish mutations and four have been previously found in other European populations. Six different BRCA2 mutations were found in 11 families. Altogether only 21% of the breast cancer families were accounted for by mutations in these two genes. Linkage to both chromosome 17q21 (BRCA1) and 13q12 (BRCA2) was also excluded in a subset of seven mutation-negative families with four or more cases of breast or ovarian cancer. These data indicate that additional breast and breast-ovarian cancer susceptibility genes are likely to be important in Finland. PMID- 9361039 TI - A novel gene that encodes a protein with a putative src homology 3 domain is a candidate gene for familial juvenile nephronophthisis. AB - Familial juvenile nephronophthisis (NPH) is an autosomal recessive, genetically heterogeneous disorder, representing the most frequent inherited cause of chronic renal failure in children. One of the responsible loci, NPH1 , has been mapped to 2q13. The presence of large homozygous deletions of approximately 250 kb in the majority of affected patients allowed us to define a minimal deletion interval for NPH1 . A BAC contig covering this interval was established. Combination of large scale genomic sequencing, cDNA selection and computer-aided analysis led to the characterization of two transcriptional units. One encodes the already known BENE protein, and the other encodes a novel protein of at least 732 amino acids containing a putative src homology 3 domain. In two patients carrying the large deletion of the NPH1 region on only one allele, two mutations were detected in two independent exons of the novel gene. One consists of a single base deletion, causing a frameshift, and the other is a G-->A substitution in the consensus 5' splice donor site. Both mutations thus potentially generate null mutants. One of these mutations was found to segregate with the disease in the family, and the second appeared to be a de novo mutation. We therefore conclude that this novel gene is a strong candidate for NPH. PMID- 9361040 TI - Sinusitis and its imaging in the pediatric population. AB - Imaging studies for sinusitis add little to the clinical management of the pediatric patient in most instances. The findings shown by paranasal sinus imaging are nonspecific and need to be correlated with clinical findings. Coronal CT is recommended for complications or for recurrent or persistent sinus disease. PMID- 9361041 TI - Geniculate ganglion meningioma. AB - Primary ectopic meningiomas are rare, but may be seen in the head and neck region. The temporal bone and its neural foramen are rarely the site of a primary meningioma. This report describes the CT and MRI appearance of an ectopic meningioma arising at the anatomic location of the geniculate ganglion, and discusses the differential diagnosis as well as the possible origin of the tumor. PMID- 9361043 TI - Transvenous embolisation of an arteriovenous malformation of the mandible via a femoral approach. AB - Arteriovenous malformations (AVM) of the mandible are uncommon but can give rise to sudden massive haemorrhage. Transarterial or direct transosseous embolisation can be used to treat this condition but is not always effective. We describe a case of mandibular AVM with a single draining vein which was embolised successfully via a femoral transvenous approach. PMID- 9361042 TI - Cholescintigraphy in the evaluation of bile flow after Roux-en-Y hepatico jejunostomy and hepatico-antrostomy in infants with choledochal cysts. AB - BACKGROUND: The study tests the hypothesis that stasis of bile in the Roux-en-Y hepatico-jejunostomy (RYJS) loop might facilitate biliary reflux and cause cholangitis, whereas quicker transit times in hepatico-antrostomy (HAST) might prevent cholangitis. MATERIALS AND METHODS: Cholescintigraphy was performed using Tc99m-trimethyl-Br-IDA in seven RYJS patients and in five HAST patients. RESULTS: The time to peak (Tmax) within the RYJS loop occurred between 18 and 50 min postinjection in all patients and the mean transit time (MTT) ranged between 42 and 69 min in 5/7 patients. Prolonged clearance of the tracer from the liver was seen in 2/7 RYJS patients, in whom the MTT was 77 and 240 min, respectively. In the HAST group, the Tmax within the anastomosed antrum occurred between 5 and 33 min postinjection, and the MTT ranged between 42 and 44 min in 2/5 patients. Protracted tracer uptake in the liver in one patient and localised tracer retention in the left hepatic bile ducts in 2/5 patients caused prolonged MTTs. Recurrent cholangitis and diarrhoea occurred in 4/7 RYJS patients, but in none of the HAST patients. Elevated gastrin levels after RYJS contrasted sharply to normal gastrin levels after HAST. CONCLUSION: The findings on cholescintigraphy did not differ significantly between RYJS and HAST and provided no explanation for the distinctly different postoperative clinical course of both surgical methods. Nevertheless, we consider cholescintigraphy to be an efficient and cost effective diagnostic modality for evaluation of the surgical outcome as regards biliary flow. PMID- 9361044 TI - Urinary bladder perforation: an unusual complication of neonatal nasogastric tube feeding. AB - Nasogastric tube (NGT) feeding is an accepted method of feeding premature infants. This case report records an unusual and previously unreported complication of NGT feeding in a neonate. PMID- 9361045 TI - Evaluation of abdominal lymphadenopathy in children by ultrasonography. AB - BACKGROUND: There may be uncertainty as to whether enlarged abdominal lymph nodes (LNs) in children are normal or abnormal. OBJECTIVE: To compare, by ultrasonography (US), enlarged abdominal LNs in healthy children with those in children with acute abdominal pain or acute gastroenteritis. MATERIALS AND METHODS: One hundred and twenty-two asymptomatic children were selected by questionnaire and compared with 44 children with acute abdominal pain of unknown origin and 27 children with acute gastroenteritis. The number of LNs, their location, their shape and the presence of tenderness as detected by finger compression of each LN were evaluated. The children were divided into four groups according to age: 0-2, 3-6, 7-10, and 11-15 years. RESULTS: LNs were detected in the ileo-caecal and/or para-aortic areas in almost all of the asymptomatic children. The number of large LNs ( > 10 mm) in the para-aortic areas was higher in the older children (>/= 7 years of age) than in the younger children ( = 6 years of age) (P < 0.05). The number of spindle-shaped LNs (ratio of long- to short-axis diameter >/= 2.0) was increased in the older children. The number of LNs was not increased in the children with acute abdominal pain. The size of the LNs was largest in the children with acute gastroenteritis, followed by the children with acute abdominal pain and the asymptomatic children (P < 0.001). Although the shape of the LNs was no different among the three groups of children, the frequency of round-shaped LNs (ratio of long- to short-axis diameter < 2.0) was greater in the older children with acute abdominal pain or acute gastroenteritis than in the asymptomatic children (P < 0.01). The number of LNs with tenderness detected by finger compression was significantly greater in the children with acute abdominal pain and acute gastroenteritis than in the asymptomatic children (P < 0.0001). CONCLUSION: The number of large and round shaped LNs with tenderness tended to be increased in the children with acute gastroenteritis and acute abdominal pain. There is no clear specificity of LN enlargement in the children with acute abdominal pain, and the main challenge is to diagnose or estimate the organic pathology by US, regardless of the presence of lymphadenopathy. PMID- 9361046 TI - Erratum: metachondromatosis: report of a family with facial features mildly resembling trichorhinophalangeal syndrome (Pediatr radiol (1997) 27: 436-441) AB - LANGUAGE="EN">In the first paragraph of the Materials and methods section the authors wrote that "the family was studied after informal written consent", This should have read "informed written consent." PMID- 9361047 TI - Magnetic resonance imaging of renal osteodystrophy in children. AB - BACKGROUND: Improved life expectancy of children with chronic renal failure (CRF) has increased the number of patients with renal osteodystrophy and has brought to light novel and severe forms of the disease. These factors have contributed to the need to evaluate new, noninvasive imaging modalities for the detection of bone involvement. OBJECTIVES: To evaluate the potential of MRI in the detection of the bone changes of renal osteodystrophy as compared to conventional X-rays. MATERIALS AND METHODS: Fourteen children with CRF were examined with a 0.5-T MR unit using TI-weighted and STIR sequences and conventional radiographs. The following features were reviewed in a nonblinded study: skeletal deformities, thickening of cortical bone, trabecular pattern, intraosseous soft-tissue masses, osteonecrosis, extraskeletal calcifications and bone marrow signal changes. RESULTS: MRI adequately demonstrated skeletal deformities, cortical thickening and irregular trabecular pattern. It showed osteonecrosis and intraosseous soft tissue masses more conspicuously than X-ray. In addition, it revealed diffuse nonspecific signal changes in the bone marrow. CONCLUSION: MRI is a potentially useful tool for evaluating the bone changes of renal osteodystrophy. PMID- 9361048 TI - Iron overload following bone marrow transplantation in children: MR findings. AB - OBJECTIVE: The purpose of this study was to determine the incidence of post transfusional iron overload in children after bone marrow transplantation by reviewing their magnetic resonance imaging (MR) findings. MATERIALS AND METHODS: We reviewed the abdominal MR studies of 13 children after autologous bone marrow transplantation. Nine of the children had also undergone MR prior to transplantation. Iron deposition in the liver, spleen and bone marrow was graded semi-quantitatively on both T1- and T2-weighted images. Serum ferritin levels and number of blood units given after bone marrow transplantation were recorded. RESULTS: None of the pre-transplantation MR studies revealed iron overload. After bone marrow transplantation, three children showed normal liver and spleen. Iron overload in the liver was noted in ten patients (77 %), six of whom also showed iron overload in the spleen (46 %) and five in the bone marrow (38.5 %). The degree of hepatic iron overload was correlated significantly and splenic iron overload was correlated weakly with the number of blood transfusions (P = 0.01 and P > 0.01, respectively), but neither was correlated with the serum ferritin level. CONCLUSION: Iron overload commonly accompanies bone marrow transplantation. The observed pattern of iron deposition, in which the spleen was uninvolved in 40 % of patients demonstrating iron overload, is not typical of post-transfusional hemochromatosis. PMID- 9361049 TI - Pulmonary and mediastinal lesions in children with Langerhans cell histiocytosis. AB - Langerhans cell histiocytosis (LCH) is an uncommon group of disorders affecting mainly children and young adults. In children, pulmonary involvement occurs mostly in the disseminated forms; isolated pulmonary lesions are unusual. A retrospective study was undertaken on a group of 42 children diagnosed with LCH over a 19-year period. Eight children (19 %) had radiological evidence of pulmonary involvement. The lung lesions were either present at the time of diagnosis or, when appearing during the course of the disease, always coinciding with exacerbation or recurrence of the disease in other sites. Lung involvement did not appear to be an unfavourable prognostic factor. However, the toxic effects of treatment on the lungs might lead to important pulmonary sequelae. PMID- 9361050 TI - HRCT features in a 5-year-old child with follicular bronchiolitis. AB - High-resolution CT (HRCT) is the most sensitive radiographic method to image small airways disease. We discuss the HRCT features of follicular bronchiolitis in a 5-year-old boy and correlate them with the histopathological findings. The changes described include centrilobular nodules, bronchiectasis and bronchiolectasis, branching opacities and areas of reduced lung attenuation. PMID- 9361051 TI - Chest radiographic data acquisition and quality assurance in multicenter studies. AB - BACKGROUND: Multicenter studies rely on data derived from different institutions. Forms can be designed to standardize the reporting process allowing reliable comparison of data. OBJECTIVE: The purpose of the report is to provide a standardized method, developed as a part of a multicenter study of vertically transmitted HIV, for assessing chest radiographic results. MATERIALS AND METHODS: Eight hundred and five infants and children were studied at five centers; 3057 chest radiographs were scored. Data were entered using a forced-choice, graded response for 12 findings. Quality assurance measures and inter-rater agreement statistics are reported. RESULTS: The form used for reporting chest radiographic results is presented. Inter-rater agreement was moderate to high for most findings, with the best correlation reported for the presence of bronchovascular markings and/or reticular densities addressed as a composite question (kappa = 0.71). The presence of nodular densities (kappa = 0.56) and parenchymal consolidation (kappa = 0.57) had moderate agreement. Agreement for lung volume was low. CONCLUSION: The current tool, developed for use in the pediatric population, is applicable to any study involving the assessment of pediatric chest radiographs for a large population, whether at one or many centers. PMID- 9361052 TI - Radiologic-pathologic conference of Children's Hospital Boston: a palpable pelvic mass in an adolescent girl. PMID- 9361053 TI - Intraosseous contrast infusion: efficacy and associated findings. PMID- 9361054 TI - Radical resection of meningiomas and arteriovenous fistulas involving critical dural sinus segments: experience with intraoperative sinus pressure monitoring and elective sinus reconstruction in 10 patients. AB - OBJECTIVE: Radical resection of meningiomas and dural arteriovenous fistulas involving functional major dural sinuses entails the risk of intracranial hypertension and venous infarction. Surgical reconstruction of dural sinuses and bridging veins increases the spectrum of dural sinus conditions that can be treated by complete resection, but indications for venous reconstructions and associated risks are still not well defined. We report our experience with sinus reconstruction based on the intraoperative assessment of collateral venous flow. METHODS: Radical resection of meningiomas (n = 5) or dural arteriovenous fistulas (n = 5) involving critical segments of dural sinuses was performed in 10 patients. All but two patients were suffering from recurrent disease after incomplete treatment. Tolerance of sinus occlusion was assessed intraoperatively by measuring stump pressure in the superior sagittal sinus during test clamping of the involved sinus segment. RESULTS: In five patients, the results of pressure monitoring suggested that occlusion of the sinus might not be tolerated. In two other patients, major bridging veins entered the diseased segment. In these patients, the resected sinus segment was reconstructed and bridging veins were reinserted as far as possible. Postoperative graft occlusion occurred in two patients. One patient who was managed without reconstruction sustained a transient postoperative neurological deficit resulting from venous congestion in the vein of Labbe. Postoperative imaging confirmed total elimination of the pathological process in all 10 patients. There was no recurrence of disease during follow-up periods of up to 8 years. CONCLUSION: The monitoring of sinus pressure, together with the possible reconstruction of the diseased sinus, allows complete surgical treatment of dural sinus abnormalities and involves acceptable risk. PMID- 9361055 TI - Treatment of cranial base meningiomas with linear accelerator radiosurgery. AB - OBJECTIVE: Radiosurgery is increasingly being used to treat cranial base tumors. Since 1989, 55 patients with cranial base meningiomas were treated at Stanford University Medical Center with linear accelerator radiosurgery. An analysis of the clinical and radiographic results of this patient population was the focus of this study. METHODS: The mean patient age was 55.1 years (range, 28-82 yr). The mean tumor volume was 7.33 cm3 (range, 0.45-27.65 cm3). The radiation dose averaged 18.3 Gy (range, 12-25 Gy), delivered with an average of 2.2 isocenters (range, 1-5). Patients were evaluated retrospectively through clinic notes from follow-up examinations, and residual tumor volume was measured during follow-up imaging studies. The length of follow-up averaged 48.4 months (range, 17-81 mo). RESULTS: Tumor stabilization after radiosurgery was noted in 38 patients (69%), shrinkage in 16 patients (29%), and enlargement in only 1 patient (2%). The results of follow-up magnetic resonance imaging demonstrated decreased central contrast uptake in 11 meningiomas (20%), possibly indicating evidence of central tumor necrosis or tumor vessel obliteration. Neurological status was improved in 15 patients in the series (27%) and unchanged in 34 patients (62%). Three patients (5%) died during the follow-up period, all as a result of causes other than tumor progression. Three patients (5%) developed new permanent symptoms (one patient with seizures, one patient with mild right hemiparesis, and one patient with both vagal and hypoglossal nerve palsy). All other complications were transient, including partial trigeminal nerve palsy in seven patients and diplopia in three patients. The 2-year actuarial tumor control rate was 98%. CONCLUSIONS: Although our follow-up period is short, this experience corroborates previous reports that radiosurgery can be used to ablate selected small cranial base meningiomas, with good clinical results and modest morbidity. PMID- 9361056 TI - Quantitative imaging study of extent of surgical resection and prognosis of malignant astrocytomas. AB - OBJECTIVE: This study used quantitative radiological imaging to determine the effect of surgical resection on postoperative survival of patients with malignant astrocytomas. Previous studies relied on the surgeons' impressions of the amount of tumor removed, which is a less reliable measure of the extent of resection. METHODS: Information concerning possible prognostic factors was collected for 75 patients undergoing magnetic resonance imaging or computed tomography preoperatively and within 10 days postoperatively. Image analysis of the neuroradiological studies was conducted to quantify pre- and postoperative total tumor volumes and enhancing volumes. Univariate and multivariate proportional hazards models were used to analyze the regression of survival regarding 22 covariates that might affect survival. The covariates that were entered included age, gender, tumor grade, cumulative radiation dose, chemotherapy, seizures as a first symptom, Karnofsky performance status at presentation, pre- and postoperative total and enhancing tumor volumes, ratio of pre- to postoperative total and enhancing tumor volumes, tumor location, surgeon's impression of the degree of resection, and subsequent surgery. RESULTS: There were 23 patients with anaplastic astrocytomas and 52 with glioblastomas multiforme. The estimated mean survival time was 27 months for patients undergoing gross total resection, 33 months for subtotal resection, and 13 months for open or stereotactic biopsy. Five factors that were significant predictors of survival in multivariate analysis were tumor grade, age, Karnofsky performance status, radiation dose, and postoperative complications (P < 0.05). In univariate analysis, tumor grade, radiation dose, age, Karnofsky status, complications, presence of enhancing tumor in postoperative imaging, and postoperative volume of enhancing tumor were significantly associated with survival (P < 0.05). CONCLUSION: We conclude that the most important prognostic factors affecting survival of patients with anaplastic astrocytomas and glioblastomas multiforme are tumor grade, age, preoperative performance status, and radiation therapy. Postoperative complications adversely affect survival. Aggressive surgical resection did not impart a significant increase in survival time. Surgical resection may improve survival, but its importance is less than that of other factors and may be demonstrable only by larger studies. PMID- 9361057 TI - Intraventricular immunotoxin therapy for leptomeningeal neoplasia. AB - OBJECTIVE: The goals of this clinical trial of intraventricular 454A12-rRA therapy were to identify dose-limiting toxicities, to evaluate the pharmacokinetics of single-dose intraventricular 454A12-rRA, and to detect antitumor activity. METHODS: We performed a pilot study of intraventricular therapy with the immunotoxin 454A12-rRA in eight patients with leptomeningeal spread of systemic neoplasia. The immunotoxin 454A12-rRA is a conjugate of a monoclonal antibody against the human transferrin receptor and recombinant ricin A chain, the enzymatically active subunit of the protein toxin ricin. Patients were treated with single doses of 454A12-rRA ranging from 1.2 to 1200 micrograms. RESULTS: The early phase half-life of 454A12-rRA in ventricular cerebrospinal fluid (CSF) averaged 44 +/- 21 minutes, and the late phase half-life averaged 237 +/- 86 minutes. The clearance of the immunotoxin was faster than the clearance of coinjected technetium-99m-diethylenetriamine penta-acetic acid, averaging approximately 2.4-fold greater. No 454A12-rRA degradation was detected by Western blot analysis of ventricular CSF for a period of 24 hours, and bioactivity was retained in CSF paralleling the concentration of immunotoxin. No acute or chronic drug toxicity was identified in patients who received less than or equal to 38 micrograms of 454A12-rRA by intraventricular injection. Doses more than or equal to 120 micrograms caused a CSF inflammatory response that was associated with transient headache, vomiting, and altered mental status. This acute syndrome was responsive to steroids and CSF drainage. No systemic toxicity was detected. In four of the eight patients, a greater than 50% reduction of tumor cell counts in the lumbar CSF occurred within 5 to 7 days after the intraventricular dose of 454A12-rRA; however, no patient had their CSF cleared of tumor, and clinical or magnetic resonance imaging evidence of tumor progression was demonstrated in seven of the eight patients after treatment. CONCLUSION: Tumoricidal concentrations of the immunotoxin 454A12-rRA can be attained safely in the CSF of patients with leptomeningeal tumor spread. PMID- 9361058 TI - Tenascin-C expression in the cyst wall and fluid of human brain tumors correlates with angiogenesis. AB - OBJECTIVE: Tenascin-C (TN) is an extracellular matrix glycoprotein with a characteristic six-armed structure. The aim of this study was to determine whether the concentration of TN in the cyst fluid of brain tumors can be used as a marker for angiogenesis and glioma grade. METHODS: We investigated the expression of TN in the cyst wall and cyst fluid of human brain tumors by immunohistochemistry, immunoprecipitation, and immunoblotting. The tumors included 12 astrocytomas (5 glioblastoma multiforme tumors, 1 anaplastic astrocytoma, 1 low-grade astrocytoma, 4 juvenile pilocytic astrocytomas, and 1 mixed glioma), 2 dysembryoplastic neuroepithelial tumors, 3 craniopharyngiomas, 2 ependymomas, 2 metastatic carcinomas, 3 arachnoid cysts, 1 glial ependymal cyst, and 1 inflammatory cyst. RESULTS: We detected no expression of TN in the cyst fluids of the ependymomas, craniopharyngiomas, and nonpilocytic low-grade astrocytoma. By contrast, TN was detected in the cyst fluids of all the other tumors. Results of quantitative immunoblotting using a PhosphorImager unit (Molecular Dynamics, Sunnyvale, CA) revealed that, on average, a 5-fold higher signal was observed in the glioblastoma multiforme tumors as compared with the anaplastic astrocytoma, and a 10-fold higher signal as compared with the mixed glioma, juvenile pilocytic astrocytomas, and dysembryoplastic neuroepithelial tumors. Results of TN immunohistochemistry in the astrocytomas correlated with glioma grade, with stronger staining of the hyperplastic vessels and tumor cells being observed in higher grade gliomas. No TN immunoreactivity was detected in the walls of the ependymomas, arachnoid cysts, and glial ependymal cyst that lack hyperplastic vessels, and minimal TN immunoreactivity was observed in the perivascular gliotic rim of the craniopharyngiomas. No TN was detected in the cyst fluid of these cystic processes. CONCLUSION: The presence of TN in and around the hyperplastic vessels and tumor cells present in the cyst walls of astrocytomas and its deposition in the intratumoral cyst fluid in which angiogenic factors have been detected further suggests a role for TN as an angiogenic modulator. These preliminary results suggest that immunodetection of TN in the tumor cyst fluid may indicate tumor type and grade. PMID- 9361059 TI - Mass effect caused by clinically unruptured cerebral arteriovenous malformations. AB - OBJECTIVE: It is generally considered that mass effect caused by arteriovenous malformations (AVMs) is evidence of ruptures. In the present study, the incidence of mass effect in clinically unruptured AVMs was evaluated, and the underlying causative factors and pathophysiological mechanisms were studied. METHODS: Twenty seven patients with clinically unruptured supratentorial pial AVMs were examined. The majority were suffering from epilepsy, and frontal lobe involvement was revealed in approximately half of the patients. Angiographic studies, computed tomographic scans, and magnetic resonance images were obtained for all patients. Twenty-one patients underwent removal of AVMs. In 10 of the surgically treated patients, intraoperative vascular pressure measurements were obtained before removal of the AVMs. RESULTS: Mass effect was detected in 12 (44%) of the 27 patients. Cortical sulci obliteration (eight patients) and lateral ventricle displacement (seven patients) were frequently noted. The volume of AVMs was significantly larger in patients with mass effect than in those without mass effect (P < 0.001). Large dilated venous sacs or ectatic veins were observed to be associated with mass effect (P < 0.001). In only one patient was gross displacement related to a surrounding massive brain edema. Draining vein pressure in patients with mass effect was significantly elevated as compared to the average value in patients without mass effect (22 +/- 5 versus 12 +/- 3 mm Hg) (P < 0.01). CONCLUSION: The present study suggests that mass effect is not infrequent in clinically unruptured AVMs. Furthermore, multiple causative factors were detected, including the large size of AVMs, marked draining vein dilatation, and brain edema around the AVMs. Findings also indicated that a pathophysiologically high pressure in the venous drainage system may contribute to mass effect. PMID- 9361060 TI - Evaluating the effect of superficial temporal artery to middle cerebral artery bypass on pure motor function using motor activation single photon emission computed tomography. AB - OBJECTIVE: We evaluated and analyzed the effect of superficial temporal artery to middle cerebral artery bypass for internal carotid artery occlusion on pure motor function using motor activation single photon emission computed tomography. METHODS: Motor activation single photon emission computed tomographic (SPECT) images were obtained for nine patients who had undergone superficial temporal artery to middle cerebral artery anastomosis for symptomatic internal carotid artery occlusion. All motor activation SPECT images using the finger opposition task on the affected side were obtained before bypass surgery and at 1 week, 1 month, and 3 months after bypass surgery. The results of motor activation single photon emission computed tomography were expressed as negative or positive. RESULTS: Before bypass surgery, the resting SPECT images revealed reduction of cerebral blood flow (CBF) on the affected side in all nine patients. The results of motor activation single photon emission computed tomography in three patients were positive. One week after bypass surgery, the results of the resting and motor activation CBF studies did not demonstrate any marked changes. One month after bypass surgery, the resting CBF increased in four patients. The results obtained for two of the patients revealed preoperative positive motor activation. The results of motor activation single photon emission computed tomography obtained for five patients were positive. Three months after bypass surgery, eight patients experienced improvement in the resting CBF, and the results of motor activation single photon emission computed tomography obtained for seven patients were positive. Among these, the results of preoperative motor activation single photon emission tomography obtained for four patients were negative. CONCLUSION: Superficial temporal artery to middle cerebral artery bypass is useful not only for resting CBF but also for pure motor function based on motor activation SPECT images. From the preoperative motor activation study, it was concluded that patients with preoperative positive motor activation could attain the effect of bypass earlier than patients with preoperative negative motor activation. PMID- 9361061 TI - Risk factors for neurosurgical site infections after craniotomy: a prospective multicenter study of 2944 patients. The French Study Group of Neurosurgical Infections, the SEHP, and the C-CLIN Paris-Nord. Service Epidemiologie Hygiene et Prevention. AB - OBJECTIVE: To determine the incidence and risk factors of surgical site infections (SSIs) after craniotomy and to test the risk index score proposed by the National Nosocomial Infections Surveillance (NNIS) system, which, to our knowledge, has not been validated in neurosurgery to date. METHODS: During a 15 month period, every adult patient undergoing craniotomy in 10 neurosurgical units was prospectively evaluated for development and risk factors of SSI. The follow up period was at least 30 days. SSIs were defined according to the Center for Disease Control definitions. Incidence was calculated per patient. Multivariate analyses were conducted at first to include all significant risk factors of univariate analysis and then only those known preoperatively. Finally, the NNIS risk index was tested in this population. RESULTS: Of a total of 2944 patients, 117 patients (4%) with SSIs were observed, including 30 with wound infections, 14 with bone flap osteitis, 56 with meningitis, and 17 with brain abscesses. Independent risk factors for SSIs were postoperative cerebrospinal fluid leakage (odds ratio, 145; 95% confidence interval, 72-293) and subsequent operation (odds ratio, 7; 95% confidence interval, 4-12). Independent predictive risk factors were emergency surgery, clean-contaminated and dirty surgery, an operative time longer than 4 hours, and recent neurosurgery. Absence of antibiotic prophylaxis was not a risk factor. The NNIS risk index was effective in identifying at-risk patients. CONCLUSION: Independent risk factors for SSIs after craniotomy involve postoperative events. However, the NNIS risk index is effective in identifying at risk patients. PMID- 9361063 TI - Surgical resection of intramedullary spinal cord cavernous malformations: delayed complications, long-term outcomes, and association with cryptic venous malformations. AB - OBJECTIVE: To examine outcomes and delayed complications after the surgical resection of intramedullary spinal cord (IMSC) cavernous malformations. The association of these lesions with cryptic intraparenchymal venous malformations at surgery also was analyzed. METHODS: The records of 17 patients who underwent resection of their histologically verified IMSC cavernous malformations were analyzed. There were nine female and eight male patients (mean age, 40.1 yr). The locations of the cavernous malformations were as follows: cervical, eight; thoracic, eight; and conus medullaris, one. The mean follow-up period was 48.3 months. Immediate postoperative and long-term neurological outcomes were compared, and delayed complications were assessed. RESULTS: The patients presented with radiculopathy (n = 6), myelopathy (n = 10), and conus medullaris syndrome (n = 1). Intraoperatively, 16 (94.1%) IMSC cavernous malformations were associated with cryptic venous malformations. Immediately after surgery, four (23.5%) patients worsened neurologically whereas one (5.9%) improved. At long term follow-up, however, 10 (58.9%) patients had improved and only 1 (5.9%) remained worse. Four (23.5%) patients experienced delayed complications. Three had undergone incomplete resection and experienced subsequent hemorrhage, necessitating subsequent resection. Another patient developed radiological tethering of the thoracic spinal cord without clinical symptoms. Two of the three patients who had undergone subsequent resection developed symptomatic tethering of the cervical spinal cord. In one of the two patients, the tethering was associated with an iatrogenic cerebellar tonsillar herniation. Both patients required surgical intervention. CONCLUSIONS: The frequent coexistence of IMSC cavernous malformations with cryptic venous malformations in this series indicates a need for operative vigilance to preserve these venous anomalies. Delayed complications were the result of incomplete resection. The resultant hemorrhage required reexploration, which led to tethering of the spinal cord. Most patients who underwent resection, however, had improved neurologically at long-term follow-up. PMID- 9361062 TI - Continuous monitoring of cerebral substrate delivery and clearance: initial experience in 24 patients with severe acute brain injuries. AB - OBJECTIVE: Current neuromonitoring techniques in severe human head injury often fail to detect the causes of clinical deterioration. A sensor is now available for continuous monitoring of brain oxygen tension, carbon dioxide tension, and pH values. In this study, brain tissue oxygen tension was used to differentiate patients at risk for brain ischemia and to predict outcome. METHODS: The multiparameter sensor was inserted into brain tissue, along with a standard ventriculostomy catheter and a microdialysis probe, in 24 patients. Lactate and glucose were measured by high-pressure liquid chromatography in hourly dialysate samples. RESULTS: Patients who experienced a good recovery (n = 8) sustained a mean brain partial oxygen pressure of 39 +/- 4 mm Hg, brain partial carbon dioxide pressure (PCO2) of 50 +/- 8 mm Hg, and a brain pH of 7.14 +/- 0.12. Patients with moderate to severe disability (n = 6) sustained a mean brain partial oxygen pressure of 31 +/- 5 mm Hg, brain PCO2 of 47 +/- 2 mm Hg, and a brain pH of 7.11 +/- 0.12. Ten patients who died or remained vegetative sustained a mean brain partial oxygen pressure of 19 +/- 8 mm Hg, a brain PCO2 of 64 +/- 21 mm Hg, and a brain pH of 6.85 +/- 0.41. Mean brain PCO2 levels of 90 to 150 mm Hg were consistently observed after cerebral circulatory arrest or brain death. Dialysate lactate and glucose were less clearly correlated to outcome than brain oxygen tension. Dialysate glucose was extremely low in all patients and zero in most patients who died. CONCLUSION: Brain oxygen pressure, brain carbon dioxide pressure, and brain pH measurements, as well as a microdialysis probe for glucose and lactate analysis, may optimize the management of comatose neurosurgical patients by allowing a fuller understanding of the dynamic factors affecting brain metabolism. PMID- 9361064 TI - Intramedullary pressure in syringomyelia: clinical and pathophysiological correlates of syrinx distension. AB - OBJECTIVE: The pathophysiological effects of syrinx distension are incompletely understood. Although it is generally assumed that the accumulation of fluid within syrinx cavities can contribute to neurological dysfunction, there are no reports describing intramedullary pressure in syringomyelia. The purpose of the current study was to measure syrinx pressures in patients with progressive clinical deterioration and to correlate these data with neurological deficits and intraoperative physiological findings. METHODS: Intramedullary fluid pressure was measured manometrically in 32 patients undergoing syrinx shunting procedures. The data were correlated with syrinx morphology, intraoperative somatosensory evoked potentials, laser Doppler measurements of local spinal cord blood flow (six patients), and neurological findings before and after syrinx decompression. RESULTS: Syrinx pressures recorded under atmospheric conditions ranged from 0.5 to 22.0 cm H2O (mean = 7.7 cm). There was a significant elevation of the cardiac pulse (mean = 0.7 cm H2O) and the respiratory pulse (mean = 1.1 cm H2O) that was consistent with raised cerebrospinal fluid pressure. Syrinx pressures decreased to subatmospheric levels after surgical drainage. In 18 of 24 patients with predrainage somatosensory evoked potential abnormalities, syrinx decompression produced a consistent reduction of N20 latencies (mean change = 0.49 ms +/- 0.094 SE right, P = 0.002; 0.61 ms +/- 0.089 SE left, P = 0.001) and a similar but less consistent increase in N20 amplitudes (mean change = 0.17 mV +/- 0.103 SE right, P = 0.115; 0.31 mV +/- 0.097 SE left, P = 0.027). Measurements of local spinal cord blood flow revealed very low baseline values (mean = 12.2 arbitrary units +/ 13.9 standard deviation), which increased to intermediate levels (mean = 144.7 arbitrary units +/- 42.6 standard deviation) after syrinx decompression. Patients with syrinx pressures greater than 7.7 cm H2O tended to have more rapidly progressive symptoms, exhibited greater improvements after shunting, and had a higher incidence of postoperative dysesthetic pain. CONCLUSION: The current study is the first to measure intramedullary pressure in a human disease. Evidence is presented that distended syringes are associated with varying levels of raised intramedullary pressure that can accentuate or induce neurological dysfunction by the compression of long tracts, neurons, and the microcirculation. Symptoms referrable to raised intramedullary pressure are potentially reversible by syrinx decompression. PMID- 9361065 TI - Outcome for preterm infants with germinal matrix hemorrhage and progressive hydrocephalus. AB - OBJECTIVE: An analysis of 76 preterm infants with Grade III or IV intracranial hemorrhage and surgically treated progressive hydrocephalus was undertaken to determine mortality, intellectual impairment, and motor deficit. METHODS: The variables examined were degree of prematurity, birth weight, sex, Apgar scores, extent of intracranial hemorrhage, seizures, age at time of initial placement of a ventricular catheter reservoir to control hydrocephalus, need to convert the reservoir to a ventriculoperitoneal shunt, timing of the conversion of the reservoir to a ventriculoperitoneal shunt, and number of shunt revisions. Outcome was assessed for statistical significance using hierarchical linear regression and logistic regression analyses. RESULTS: Linear regression analysis determined that mortality was best predicted, in order of importance, by extent of intracranial hemorrhage, number of shunt revisions, and birth weight (P < 0.0001, R = 0.79). Grade of hemorrhage, weight at birth, and presence of seizure activity were the most important determinants of motor outcome (P < 0.001, R = -0.78). CONCLUSIONS: Logistic regression analysis of the 41 long-term survivors determined that grade of hemorrhage was the most important variable in determining cognitive outcome (P < 0.0001), motor function (P < 0.0001), and presence of seizure activity (P < 0.001). A logistic model of survival determined that grade of hemorrhage and multiple shunt revisions (more than five) were the most important determinants (P < 0.0001) of survival. In conclusion, the overwhelming factor in determining outcome in this patient group was the extent of intracranial hemorrhage. PMID- 9361066 TI - Direct microsurgery of dural arteriovenous malformation type carotid-cavernous sinus fistulas: indications, technique, and results. AB - OBJECTIVE: There is a subgroup of patients with Barrow Type D carotid-cavernous sinus fistulas (CCFs) who have progressive neurological deficits despite endovascular attempts at obliteration. To effectively arrest the progression of neurological deficits, especially visual loss, these patients require direct operative intervention. We have used a direct approach to such lesions, which comprehensively occludes all fistulous connections of the CCF. METHODS: We present a series of nine patients with Type D CCFs for which attempts at endovascular embolization failed and that, because of persistent symptoms, required surgical intervention. These lesions characteristically had extensive multiple external carotid artery feeders, often bilateral, in addition to the internal carotid artery feeders. The operative approach used was a combined extra and intradural full exposure of the cavernous sinus and its contents, with identification and direct obliteration of all arterial input and selective ablation of the venous outflow from the cavernous sinus. RESULTS: All nine patients experienced resolution of their symptoms, and complete ablation of the lesions, as demonstrated by postoperative angiography, was achieved. Transient diplopia and trigeminal hypesthesia was observed in all nine patients, which resolved by 6 months postoperatively. One patient suffered from a temporary hemiparesis and another from permanent hemiparesis. There were no deaths related to surgery in this series. CONCLUSIONS: Patients with Type D CCFs who have persistent, progressive neurological deficits after failed endovascular attempts at obliteration may be treated by a direct surgical approach to ablate the fistulas. The pertinent anatomic concepts, indications for surgery, and operative techniques that are different from previously described methods are discussed. PMID- 9361067 TI - Occipitotranstentorial approach for lesions of the superior cerebellar hemisphere: technical report. AB - OBJECTIVE: The occipitotranstentorial approach is well accepted for lesions of the pineal region, superior cerebellar vermis, or mesencephalon. Although evidently suitable, this approach has not, to our knowledge, been reported for lesions of the superior cerebellar hemisphere in adults. Experience with this approach is reported. METHODS: Four patients underwent surgery between August 1995 and March 1997. The findings obtained are evaluated. RESULTS: All lesions were situated in the quadrangular lobules (one extending into the vermis), and all were completely removed. Postoperative deficits, especially visual field deficits, did not occur. CONCLUSION: Lesions of the superior cerebellar hemispheres are easily approached by an occipitotranstentorial route. The major advantages over a supracerebellar approach are that the surgical route is nearly perpendicular to the lesion and to the tentorium instead of parallel, and wide exposure is thereby possible. PMID- 9361068 TI - Experimental study for identification of the facial colliculus using electromyography and antidromic evoked potentials. AB - OBJECTIVE: The facial colliculus is a reliable landmark for a surgical approach via the fourth ventricle. Our aim is to elucidate the most suitable electrophysiological methods for identification of the facial colliculus. We evaluated the usefulness of facial electromyography and antidromic evoked potentials of the facial nerve. The effect of stimulation on cardiorespiratory function is also studied. METHODS: We localized the facial colliculus by facial electromyography and antidromic facial evoked potentials in adult dogs. To determine the most effective stimulus pattern, intensity was varied, and both monopolar and bipolar electrical stimulation were tried. To confirm the cardiorespiratory effect of the stimulation, systemic blood pressure, heart rate, respiratory rate, and thoracic excursion were measured. After administration of atropine sulfate, changes in vital signs were recorded. RESULTS: A stable facial electromyographic wave form was produced by 0.1-mA monopolar stimulation of a small portion of the fourth ventricular floor (4 mm2). Using 0.1-mA bipolar stimulation, the same wave form was obtained. As saline was gradually added around the electrodes, the amplitude of the response gradually decreased; however, the response with monopolar stimulation was more stable than that with bipolar stimulation. Stimulation of the facial colliculus with greater than 2 mA caused transient hypotension and bradycardia; respiratory arrest occurred with 3 mA stimulation. Administration of atropine sulfate (0.01 mg/kg) decreased these responses. Antidromic facial evoked potentials were recorded only at "hot points" that existed within 2 mm of the facial colliculus. CONCLUSION: Our study resulted in three findings. First, the most suitable electrophysiological stimulation of the fourth ventricular floor for identification of the facial colliculus was 0.1 mA monopolar stimulation. Second, significant alteration in cardiorespiratory function appeared with greater than 1-mA stimulation. Third, a recording of an antidromic facial evoked potential can identify the facial colliculus more safely than direct stimulation of the facial colliculus. Both orthodromic and antidromic methods were useful for identification of the facial colliculus in brain stem surgery. PMID- 9361069 TI - Identification of functioning cortex using cortical optical imaging. AB - OBJECTIVE: The purpose of this study was to evaluate the technique of cortical optical imaging (COI) of intrinsic cortical optical signals related to neuronal activation. The specific goals of the study were to evaluate some of the technical aspects of COI and thus maximize the intensity of the image of this intrinsic signaling process and to determine the physiological reliability of COI in a well-defined animal system. METHODS: The intrinsic optical signal of activated whisker barrel cortex of rat was imaged using a computer-based technique for rapid acquisition of enhanced images. Single-unit microelectrode recordings of cortical neuronal responses to whisker movement were used to confirm the locations of the whisker barrels. RESULTS: Narrow band incident light at 600- to 610-nm wavelength was most effective for producing optical images. Images could be obtained during activation by a single long (40 s) stimulus or by averaging the signal generated by repeated shorter (1-8 s) stimuli. Focusing slightly below the cortical surface, minimizing movement, and abolishing extraneous light were all important in increasing the signal-to-noise ratio. The locations of whisker movement-evoked cortical activity determined using COI are consistent with the known functional anatomy of rat whisker barrel cortex. The images obtained with this experimental arrangement are shown to be accurate predictors of the location of neuronal activity determined by comparing the locations of active sites identified with COI with locations of areas of neuronal activity determined using single-cell recording techniques. CONCLUSIONS: COI is able to rapidly identify areas of cortex containing elicited neuronal activity. The technique allows cortical activation maps to be made rapidly with a very high degree of spatial resolution. COI is reliable and consistent over time. COI, if used carefully, holds promise as an intraoperative technique to study both human and experimental animal cortical function. PMID- 9361070 TI - Evidence for a high free radical state in low-grade astrocytomas. AB - OBJECTIVE: It is postulated that reactive oxygen species may play an inductive role in neuro-oncogenesis. However, data pertaining to the redox state of astrocytomas are limited, which prompted us to undertake this study. METHODS: Intraoperative snap-frozen samples were obtained from the surface and core of 8 low-grade and 11 high-grade astrocytomas. Small portions of each specimen were fixed in 10% neutral formalin or cacodylate-buffered glutaraldehyde. Lipid peroxidation was estimated by measuring thiobarbituric acid-reactive substances, and total glutathione levels were determined. Light microscopy was performed to define the relevant histopathology, and electron microscopy was used to quantitate peroxisomal content. RESULTS: Thiobarbituric acid-reactive substance values for low-grade astrocytomas were significantly elevated compared to those for malignant lesions, as was the case for total glutathione. This discrepancy was especially marked at the tumor surface. Peroxisomes predominated in the low grade category. CONCLUSION: We speculate regarding malignant transformation as a possible consequence of this decline in antioxidant capacity, as well as regarding the role of seizures and astrocytoma glutamate receptors in the initiation of free radical cascades. The therapeutic and teleological implications are considerable. PMID- 9361071 TI - Inverse correlation of cell proliferation and expression of progesterone receptors in tumor spheroids and monolayer cultures of human meningiomas. AB - OBJECTIVE: The progesterone receptor (PgR) can be detected in 60 to 70% of meningiomas using immunohistochemistry] in situ. Whereas in monolayer tissue cultures the PgR is only rarely expressed, we were able recently to demonstrate the preservation of the PgR in fragment spheroid cultures of meningiomas. The aim of the present study was to evaluate the stability of PgR expression in meningioma spheroids in vitro and the correlation of PgR expression and cell proliferation in spheroids and whether meningioma cells reaggregated to spheroids from monolayer cultures to reexpress the PgR again. METHODS: Tumor fragment spheroids (Weeks 1-6) and cell monolayers (Passages 1 and 3) of 15 PgR-positive meningiomas were investigated by immunohistochemistry for the expression of PgRs and their proliferative activity, as demonstrated by positivity for the proliferation-related antigen Ki-67. To study PgR reexpression in reaggregated spheroids, Northern blots were performed. In addition, a reverse transcriptase polymerase chain reaction technique was established and evaluated in combination with immunohistochemistry. Growth of meningioma spheroids was quantified in the presence of progesterone and the specific antagonist onapristone. RESULTS: The PgR remained stable in spheroids for 6 weeks in 9 of 13 cases that were able to be evaluated. All tumor fragment spheroids exhibited a proliferation index of 5 to 40% Ki-67-positive cells. Monolayer cell cultures, on the other hand, failed to express PgRs but revealed higher proliferation indices (40-90%) to a significant extent. The detection of PgR messenger ribonucleic acid in reaggregated spheroids by means of reverse transcriptase-polymerase chain reaction correlated to the nuclear expression of PgR in immunohistochemistry. Neither progesterone nor its antagonist onapristone altered spheroid growth in vitro. CONCLUSION: The expression of the PgR in meningiomas is preserved in spheroid cultures with low proliferation indices for at least 6 weeks, whereas monolayer cell cultures with a high proliferative activity lack PgR expression. The inverse pattern of Ki-67-positive cells in the outer regions of the spheroids and PgR-expressing tumor cells in the spheroid centers leads us to the conclusion that proliferating meningioma tumor cells do not express PgRs. This might also explain why tumor cell growth in vitro was neither affected by progesterone nor by onapristone. Monolayer cell cultures can be reaggregated to spheroids, the consequence being a reexpression of PgRs and, therefore, a down-regulation of proliferation. PMID- 9361073 TI - A brief history of pallidotomy. AB - A large number of surgical procedures involving the globus pallidus and ansa lenticularis were performed from 1939 to the late 1950s for alleviation of rigidity and tremor, two of the main symptoms of Parkinson's disease. Several groups reported beneficial effects using a wide array of techniques and targets within the pallidum and its projections. Over time, pallidal targets lying in the ventral and posterior portions of the internal pallidum were considered to be the most effective. Based on anatomic studies, surgical misadventures, and empirical observations, there was an abrupt shift regarding the favored target to treat parkinsonian tremor to the thalamus, and most neurosurgeons abandoned pallidotomy in the 1960s. With the advent of L-dopa and the realization of its striking clinical benefits in the mid 1960s, within 5 to 10 years, virtually all surgery for Parkinson's disease ceased. We are now witnessing a rediscovery of pallidotomy as patients with Parkinson's disease are experiencing the shortcomings of medical therapy. In this article, we examine the evolution of pallidotomy and discuss the reasons for the renewed interest in this procedure. PMID- 9361072 TI - Endovascular occlusion of experimental aneurysms with detachable coils: influence of packing density and perioperative anticoagulation. AB - OBJECTIVE: This study was designed to assess the intraluminal biological changes after endovascular coil occlusion of arterial aneurysms with detachable coils, to analyze the relationship between histological occlusion and mechanical packing density, and to evaluate the influence of perioperative anticoagulation on the occlusion rate. METHODS: In rabbits, 30 microsurgically produced arterial bifurcation aneurysms were occluded with coils (18 with platinum coils, electrically detached; 12 with tungsten coils, mechanically detached). Coils were placed until no further coils fit into the aneurysmal lumen and it was no longer filled with radiographic contrast material. The individual degree of occlusion was then determined by the "packing density" on the angiograms. Complete occlusion was considered only if no neck remnant was visible on the films. Anticoagulation during and 2 days after the treatment was performed in 11 cases. After an observation period ranging from 3 to 6 months, angiographic and histological analyses were performed to obtain control data. RESULTS: Complete occlusion was achieved in 9 cases, subtotal occlusion (i.e., > 95% occlusion, residual filling at the neck of the aneurysm) in 10 cases, and partial occlusion in 11 cases. Angiographically documented recanalization was detected in 14 aneurysms. In the remaining 16 aneurysms, the initially documented angiographic results were unchanged. A discrepancy between angiographic and pathological findings was frequently observed. Five of nine angiographically completely occluded aneurysms were recanalized. Endothelial-like tissue at the orifice of the aneurysm was able to be observed in only four of the nine initially completely occluded aneurysms. CONCLUSION: The results suggest that even dense packing does not always guarantee permanent occlusion, although there was a positive relationship between packing density and occlusion rate. Anticoagulation did not have any negative effect on the results. PMID- 9361074 TI - Craniopharyngiomas in two consanguineous siblings: case report. AB - OBJECTIVE AND IMPORTANCE: We describe a double case of craniopharyngioma in consanguineous siblings, suggesting the disease is sometimes genetic. CLINICAL PRESENTATION: Two typical adamantine craniopharyngiomas were observed in two consanguineous siblings. The brother and the sister, whose parents were first cousins, developed the tumors at the same age. INTERVENTION: The male patient was operated on using a frontopterional approach, and the tumor was completely resected. The patient remained free from recurrence 9 years after surgery. His older sister died after tumor removal was attempted at another institution. CONCLUSION: To our knowledge, such a connection has never been reported in the literature. It suggests that craniopharyngioma, which is usually sporadic, can also be transmitted in an autosomal recessive manner. PMID- 9361075 TI - Spontaneous reduction of a recurrent craniopharyngioma in an 8-year-old female patient: case report. AB - OBJECTIVE AND IMPORTANCE: The spontaneous rupture of a craniopharyngioma is an extremely rare condition confined to adults. This is the first report of a patient younger than 10 years who experienced spontaneous reduction (possibly rupture) of a craniopharyngioma. CLINICAL PRESENTATION: An 8-year-old female patient with a recurrence of a craniopharyngioma experienced fever, headache, and visual disturbance that lasted a few days. Concurrent with the improvement of these symptoms, marked reduction in the size of the tumor was revealed using magnetic resonance imaging, suggesting the occurrence of a rupture. INTERVENTION: Subsequent magnetic resonance imaging of the hypothalamic-pituitary region was performed while the patient received growth hormone therapy. CONCLUSION: There was no increase in the size of the tumor 1 year after the reduction occurred. Prompt evaluation of the hypothalamic-pituitary region using magnetic resonance imaging is warranted to rule out the possibility of spontaneous reduction (including rupture) of the tumor in a situation in which the patient with a craniopharyngioma shows meningeal signs or a rapid change of neurological symptoms (such as headache, fever, or visual disturbance). PMID- 9361076 TI - Percutaneous transvenous coil embolization of a type 4 sagittal sinus dural arteriovenous fistula: case report. AB - OBJECTIVE AND IMPORTANCE: To present an alternative endovascular therapy for a Type 4 sagittal sinus dural arteriovenous fistula (DAVF). CLINICAL PRESENTATION: A 74-year-old man presented with right facial paresthesias. Magnetic resonance imaging revealed an enlarged left parasagittal cortical vein adjacent to the superior sagittal sinus. Angiography demonstrated a Type 4 sagittal sinus DAVF. INTERVENTION: The DAVF was cured using percutaneous transvenous coil embolization. CONCLUSION: This case represents the first report in which a sagittal sinus DAVF was cured using a percutaneous transvenous endovascular approach. PMID- 9361077 TI - Hemifacial spasm caused by a hemangioma at the geniculate ganglion: case report. AB - OBJECTIVE AND IMPORTANCE: Hemifacial spasm is rarely caused by facial nerve lesions in the temporal bone. Intratemporal facial nerve hemangiomas may initially present as facial spasm. CLINICAL PRESENTATION: A 30-year-old woman developed right hemifacial spasm. Physicians observed slight weakness on the right side of her face, in addition to the hemifacial spasm, but routine radiological examinations did not detect any abnormal findings along the course of the facial nerve. Although the patient underwent neurovascular decompression, the spasm persisted postoperatively. Two years after surgery, the right facial palsy progressed. Concurrently, the hemifacial spasm diminished. High-resolution computed tomography demonstrated a small mass lesion expanding the cortex of the right petrosal bone involving the geniculate ganglion of the facial nerve. INTERVENTION: The patient underwent a second craniotomy through a subtemporal extradural route, and the tumor was completely removed. A pathological examination demonstrated a cavernous hemangioma. CONCLUSION: Routine radiological examinations may fail to detect small intratemporal facial nerve hemangiomas, particularly at the geniculate ganglion. Therefore, when physicians encounter atypical facial spasm, the intratemporal portion of the facial nerve should be carefully examined using high-resolution computed tomography. PMID- 9361078 TI - Extradural ecchordosis physaliphora of the thoracic spine: case report. AB - OBJECTIVE AND IMPORTANCE: We report an unusual case of ecchordosis physaliphora of the thoracic spine. CLINICAL PRESENTATION: The clinical presentation was one of disabling thoracic radicular pain without objective neurological deficit. The imaging characteristics of the lesion were those of a cyst containing aqueous fluid. There was no bone destruction. INTERVENTION: Gross total removal of the lesion was accomplished. CONCLUSION: We present the only well-documented case of thoracic extradural ecchordosis physaliphora and discuss the relationship between the notochord, ecchordosis physaliphora, and chordoma. We provide a comprehensive list of lesions exhibiting physaliphorous cells. PMID- 9361080 TI - A clinical study of parenchymal and subdural miniature strain-gauge transducers for monitoring intracranial pressure. PMID- 9361079 TI - A carbon fiber reinforced polymer cage for vertebral body replacement: technical note. AB - OBJECTIVE: We analyzed the surgical technique used for the replacement of damaged vertebral bodies of the thoracolumbar spine and the carbon fiber reinforced polymer (CFRP) cages that are used to replace the pathological vertebral bodies. We also evaluated the biomechanical properties of carbon composite materials used in spinal surgery. TECHNIQUE: The surgical technique of CFRP implants may be divided into two distinct steps, i.e., assembling the components that will replace the pathological vertebral bodies and connecting the cage to an osteosynthetic system to immobilize the cage. INSTRUMENTATION: The CFRP cages, made of Ultrapek polymer and AS-4 pyrolytic carbon fiber (AcroMed, Rotterdam, The Netherlands), are of different sizes and may be placed one on top of the other and fixed together with a titanium rod. These components are hollow to allow fragments of bone to be pressed manually into them and present threaded holes at 15, 30, and 90 degrees on the external surface, permitting the insertion of screws to connect the cage to an anterior or posterior osteosynthetic system. RESULTS: To date, we have used CFRP cages in 13 patients undergoing corporectomies and 10 patients undergoing spondylectomies. None of our patients have reported complications. CONCLUSIONS: CFRP implants offer several advantages compared with titanium or surgical grade stainless steel implants, demonstrating high versatility and outstanding biological and mechanical properties. Furthermore, CFRP implants are radiolucent and do not hinder radiographic evaluation of bone fusion, allowing for better follow-up studies. PMID- 9361081 TI - Acute lung injury in isolated traumatic brain injury. PMID- 9361082 TI - Investigation of morphological change of lateral and midline fluid percussion injury in rats, using magnetic resonance imaging. PMID- 9361083 TI - Comparative study of functional recovery for surgically explored and conservatively managed spinal cord missile injuries. PMID- 9361084 TI - Operative treatment of spontaneous spinal epidural hematomas: a study of the factors determining postoperative outcome. PMID- 9361085 TI - Postnatal development of the rat exocrine pancreas. I. Alterations in high- and low-affinity cholecystokinin receptors and enzyme secretion. AB - We tested the hypothesis that postnatal alterations in cholecystokinin (CCK) receptors are associated with developmental changes in enzyme secretory response. We used simultaneous measurements of CCK receptor binding and amylase release in pancreatic acini isolated from rat pups at various ages (1, 2, 5, 6, 18, and 36 days). CCK receptor binding was analyzed using the LIGAND program. The affinity of the high-affinity state increased postnatally at 18 and 36 days (p < 0.05); the capacity of the high-affinity state also increased at 2 days (p < 0.05), then declined sequentially up to 36 days. The affinity of the low-affinity state increased postnatally reaching statistical significance at 5 days; the capacity of the low-affinity state increased twofold at 2 days, reaching statistical significance at 5 days (p < 0.05); this was followed by a slight decrease at 36 days. At 1 day postnatally a small amylase response occurred (p < 0.05), but no dose-dependent response was observed. A significant CCK dose-dependent secretory response occurred at all other ages. Maximal amylase release was highest at 18 days (p < 0.05). CCK doses required to stimulate maximal amylase release were 20, 2, 1, 0.2 and 0.4 nM at 2, 5, 6, 18, and 36 days, respectively. The receptor occupancy rates for high- and low-affinity states decreased sequentially between 2 and 18 days of age, when maximal amylase release occurred. These data suggest that more spare receptors become available with increasing postnatal age. We conclude that postnatal alterations of both high- and low-affinity states of CCK receptors in pancreatic acini are associated with developmental changes in enzyme secretory response to CCK. An increase in the affinity of high-affinity state and the capacity of the low-affinity state may enhance acinar sensitivity to CCK. PMID- 9361086 TI - Postnatal development of the rat exocrine pancreas. II. Effects of protein calorie malnutrition on amylase secretion and CCK receptor binding. AB - Malnutrition induces pancreatic atrophy and intracellular derangement, but its effects on cholecystokinin (CCK) receptors and the CCK-induced secretory response remain unclear. We used a rodent model to study the developmental effects of protein-calorie malnutrition on exocrine pancreatic function. Simultaneous experiments evaluated postnatal alterations in CCK-induced amylase response and receptor binding of pancreatic acini. At all postnatal ages, somatic and pancreatic weight of the malnourished rats was significantly below age-matched controls (p < 0.01). The malnourished rats showed a higher secretory response to CCK at 1 day of age and increased acinar sensitivity at 2 days. Maximal amylase secretion was significantly higher at 5 and 18 days (p < 0.05), but remained similar to that of the age-matched controls at 36 days. CCK receptor binding showed no significant changes at 1 and 2 days postnatally in comparison with controls. At 5 and 18 days, the affinity of the high-affinity state showed a twofold increase, while the capacity of the high-affinity state decreased by 40 55%. At the same time, the affinity of the low-affinity state increased significantly (p < 0.05), but the capacity of the low-affinity state was essentially unchanged. The acinar sensitivity of malnourished rats was consistently reduced between 5 and 36 days, which coincided with a reduction in spare receptors in the malnourished rats. In conclusion, the increased amylase secretory response at 1 and 2 days of age may be due to an adaptive response of endocrine function to maternal metabolic stress. The increased affinities of CCK receptors at 5 and 18 days may be associated with a higher secretory responsiveness, while the decreased spare receptors may contribute to a reduction in the acinar sensitivity. These results demonstrate that malnutrition induces changes in CCK binding and its secretory response. PMID- 9361087 TI - Change of pancreatic enzymes, pancreatic stone protein (PSP), and plasma alpha(2) macroglobulin-trypsin complex-like substance (MTLS) in the activation of pancreatic juice. AB - To characterize the activation of pancreatic zymogens (trypsinogen, chymotrypsinogen, and proelastase 1) in acute pancreatitis, we studied the activation of pancreatic juice with porcine enteropeptidase in vitro, and then enzymatic activities and the generation of pancreatic stone protein (PSP) S1 form in pancreatic juice were investigated. Further, we determined immunoreactive trypsin, immunoreactive elastase 1, PSP, and alpha(2)-macroglobulin-trypsin complex-like substance (MTLS) levels in plasma to which the activated juice was added. In the present report, we demonstrate that the plasma MTLS level reflected the activation of pancreatic trypsinogen in pancreatic juice. Further, the generation of PSP S1 form was found at an early stage of activation. Therefore, the plasma MTLS level and the generation of PSP S1 form may offer new diagnostic information on the amounts of activated proteases and subsequently on the severity of acute pancreatitis. PMID- 9361088 TI - Different changes in high-energy phosphates in alcoholic acute pancreatitis and taurocholate acute pancreatitis in rats using NMR spectroscopy at 2.0 T. AB - We studied the pancreatic high-energy phosphates in two models of acute pancreatitis using 31P nuclear magnetic resonance (NMR) in rats for the first time in vivo. Alcoholic pancreatitis was induced by acute ethanol intoxication and an obstruction-hyperstimulation mechanism. Taurocholate pancreatitis was generated by intraparenchymal administration of 1 ml of 1-10% taurocholate-Na+. In addition to the obligate control groups, a simple ischemia experiment was performed. The high-energy phosphates were monitored by 31P NMR spectroscopy at 2.0 T. Additionally, by means of a scoring system, the quality and quantity of pathomorphologic parameters were quantified after 24 h. 31P spectra acquired after injection of taurocholate showed an increase in inorganic phosphate with a concomitant decrease in ATP levels, similar to pancreatic ischemia. This irreversible decrease was accompanied histologically by severe pancreatic hemorrhage. After induction of alcoholic acute pancreatitis a reversible decrease in ATP was occasionally seen. Even when alcoholic pancreatitis had been fully established at 24 h, the 31P NMR spectrum was normal in all animals. In conclusion, depletion of high-energy phosphates seems to occur as a result of pancreatic cell death rather than being a cause of pancreatic necrosis. For the first time we applied in vivo NMR in the rat pancreas to study the time course in acute pancreatitis. PMID- 9361089 TI - Islet amyloid polypeptide in Psammomys obesus (sand rat): effects of nutritionally induced diabetes and recovery on low-energy diet or vanadyl sulfate treatment. AB - We investigated the possible relationship between islet amyloid polypeptide (IAPP) and the hyperinsulinemia and/or hyperglycemia that is seen in the desert adapted gerbil Psammomys obesus, when the animal is transferred from a low-energy (LE) diet to a high-energy (HE) diet. The effects of vanadyl sulfate and transition from a HE to a LE diet on the diabetic state of the Psammomys were also studied. Psammomys maintained on a LE diet, showing normoinsulinemia and normoglycemia (group A), were used as controls. IAPP and insulin immunoreactivity in the islets of Langerhans was studied using the peroxidase-antiperoxidase technique and plasma levels of the two hormones were determined by radioimmunoassays. The islet immunoreactivity of both IAPP and insulin was significantly weaker in the hyperinsulinemic and hyperglycemic Psammomys (group C) compared to group A. Transfer to a LE diet resulted in complete recovery of the IAPP- and insulin-staining pattern to that seen in group A [group A--Rec (nutrition)]. The plasma IAPP levels of the group C animals were not significantly higher than in group A, while after vanadyl sulfate treatment the IAPP levels and IAPP/insulin ratios remained significantly higher [group A--Rec (vanadyl)]. At the same time the circulating levels of glucose and insulin were restored to normal. Conclusively, islet IAPP and insulin immunoreactivity disappeared and reappeared in parallel in Psammomys transferred to a HE diet and back to a LE diet. Furthermore, vanadyl sulfate treatment of the hyperinsulinemic and hyperglycemic animals normalized circulating glucose and insulin levels, but not IAPP levels, possibly due to a negative feedback effect of IAPP on insulin release. PMID- 9361090 TI - Altered expression of insulin-like growth factor II receptor in human pancreatic cancer. AB - The insulin-like growth factor-II (IGF-II) receptor (IGF-IIR) is a single-chain transmembrane protein identical to the mannose-6-phosphate receptor. In the present study we examined IGF-IIR expression in normal and cancerous human pancreatic tissues. In the normal pancreas, moderately strong IGF-IIR immunoreactivity was present in the cytoplasm of islet cells, and mild cytoplasmic immunoreactivity was evident occasionally in ductal and acinar cells. Some ductal cells also exhibited nuclear IGF-IIR immunoreactivity. In the pancreatic cancers, regions of strong IGF-IIR immunoreactivity were present in the duct-like cancer cells within the tumor mass, often exhibiting nuclear localization. Expression of IGF-IIR mRNA in the cancer cells was confirmed by in situ hybridization. By comparison with normal pancreatic tissues, 7 of 12 pancreatic cancers exhibited a 5.6-fold increase in IGF-IIR mRNA levels, whereas in 3 cancers the IGF-IIR transcript was below the level of detection. Furthermore, all six tested cultured human pancreatic cancer cell lines expressed the IGF-IIR mRNA transcript. Our data indicate that IGF-IIR is overexpressed in a significant number of human pancreatic cancers, where it has a tendency to localize in the nucleus, and raise the possibility that IGF-IIR may contribute to the pathobiology of pancreatic cancer. PMID- 9361091 TI - Detection of mutant K-ras in dissected paraaortic lymph nodes of patients with pancreatic adenocarcinoma. AB - In this study, we attempted to detect K-ras point mutations by means of two-stage polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) to diagnose micrometastases in paraaortic lymph nodes of patients with pancreatic adenocarcinoma. Main carcinoma tissues and corresponding lymph nodes in the paraaortic region were obtained from 15 patients who underwent extended radical surgery including the wide dissection of lymph nodes and who were diagnosed as lymph node negative by routine histological examination. DNA was extracted from the tissue specimens, and PCR/RFLP analysis was used to detect K-ras oncogene mutations at codon 12. Thirteen of the primary tumors were found to have K-ras mutations. In eight of the 13 cases, 42 of the 101 lymph nodes showed K-ras point mutations in the paraaortic lymph nodes. These results suggested that PCR/RFLP analysis is potentially highly sensitive for the detection of micrometastases in lymph nodes and that it may be useful in reaching an accurate assessment of the lymphatic dissemination of pancreatic adenocarcinoma at the molecular level. PMID- 9361092 TI - Inhibition of growth and invasive activity of human pancreatic cancer cells by a farnesyltransferase inhibitor, manumycin. AB - The effects of manumycin, a competitive farnesyltransferase (FTase) inhibitor, on pancreatic cancer cell lines with or without K-ras mutation were studied. Manumycin inhibited the growth of human pancreatic cancer cells (SUIT-2, MIA PaCa 2, AsPC-1, BxPC-3) in a dose-dependent manner. The 50% inhibitory concentration (IC50) in cell lines with a mutant K-ras gene (SUIT-2, MIA PaCa-2, AsPC-1) was lower than that in BxPC-3 with a wild-type ras. Both mitogen-activated protein kinase activity after growth stimuli and the ability for chemotactic invasion were markedly more inhibited by manumycin in SUIT-2 than in BxPC-3. These results suggest that mutated Ras is more sensitive to manumycin than the wild type. Furthermore, tumor growth and liver metastasis in nude mice inoculated with manumycin-treated SUIT-2 cells were inhibited dose dependently. Inhibition of Ras activity might be a new anticancer strategy in pancreatic cancer in which Ras plays a role. PMID- 9361093 TI - Intraislet regulation of pancreatic polypeptide secretion in the isolated perfused rat pancreas. AB - The present study is to determine if intraislet insulin or somatostatin regulate pancreatic polypeptide (PP) secretion in the isolated perfused rat pancreas by infusing insulin or somatostatin antisera. Isolated rat pancreata were stimulated with either 16.7 mM glucose (G) alone, G with antisomatostatin antibody (G + SA), or G with antiinsulin antibody (G + IA). G inhibited PP secretion -22 +/- 9.5 pM below basal, a decrease of 9 +/- 6.3% (n = 6; p = NS), G + IA inhibited PP secretion -10 +/- 27.2 pM below basal, a decrease of 20 +/- 15% (n = 7, p = NS), and G + SA stimulated PP secretion 18 +/- 7.1 pM above basal, an increase of 26 +/- 5% (n = 6; p < 0.05). G stimulated insulin secretion 3,144 +/- 210 pM above basal (n = 6, p < 0.05), and G + SA stimulated insulin secretion 2,695 +/- 195 pM above basal (n = 7; p < 0.05 vs. baseline, p = NS vs. G alone). G stimulated C peptide secretion 886 +/- 175 pM above basal (n = 6; p < 0.05), G + SA stimulated C-peptide secretion 847 +/- 102 pM above basal (n = 7; p < 0.05, p = NS vs. G alone), and G + IA stimulated C-peptide secretion 834 +/- 93 pM above basal (n = 7; p < 0.05, p = NS vs. G alone). These data demonstrate that infusion of SA results in significant stimulation of PP secretion during high-G infusion, whereas IA has no effect. Infusions of SA or IA at the doses used have no effect on G-stimulated insulin or C-peptide secretion. This suggests that intraislet somatostatin may be an inhibitory regulator of PP secretion in the isolated perfused rat pancreas. PMID- 9361094 TI - Acute interstitial pancreatitis in rats induced by dibutyltin dichloride (DBTC): pathogenesis and natural course of lesions. AB - Dibutyltin dichloride (DBTC; 6 mg/kg body weight, i.v.) induced acute interstitial pancreatitis in rats. The course of the pancreatitis was examined within 28 days by light and electron microscopy as well as by pathobiochemistry (amylase, lipase, alkaline phosphatase, and bilirubin in serum; tin concentration in biliopancreatic juice, tissue, and concretions). The pathogenesis of the DBTC induced pancreatitis in rats was studied by different experimental designs (in intact animals, after bile duct ligation, after surgical bypass of the bile duct). DBTC caused toxic necrosis of the biliopancreatic duct epithelium, which is then shed into the duct and forms obstructing plugs in the distal common bile duct. Interstitial pancreatitis occurred during the first 4 days, accompanied by significantly increased activities of serum alpha-amylase and lipase. After 7 days extensive infiltration of the pancreatic interstitium with mononuclear cells was observed. Twenty-eight days after administration of DBTC one-third of the rats showed periductal and interstitial fibrosis as well as an active inflammatory process in the pancreas. The findings suggest a twofold pathogenesis of the DBTC-induced pancreatitis: first, the cytotoxic effects on the biliopancreatic duct epithelium lead to epithelial necrosis with obstruction of the duct, subsequent cholestasis, and interstitial pancreatitis; and second, the hematogenic DBTC effects cause direct injury of pancreatic cells (mitochondrial damage, autophagy, cell necrosis) followed by interstitial edema and inflammation. Both processes lead to this special type of DBTC-induced acute pancreatitis with a tendency to a chronic course, when the obstruction of the duct and cholestasis persist. PMID- 9361095 TI - Evaluating exocrine function tests for diagnosing chronic pancreatitis. AB - To evaluate the effectiveness of exocrine function tests in diagnosing chronic pancreatitis (CP), we compared the sensitivity and specificity of duodenal intubation with tubeless tests. While the secretin test (ST) was necessary to diagnose CP, especially in noncalcified CP, and tubeless tests demonstrated insufficient sensitivity to diagnose CP, the combination assay of tubeless tests was specific enough to diagnose severe exocrine dysfunction. Our studies found the sensitivity of secretin testing to diagnose definite CP to be 87%. In patients with probable CP, 60% had mild exocrine insufficiency and 40% had normal function. The false-positive rate of the ST results in nonpancreatic diseases, except diabetes mellitus, was 5%. The correlation between morphological changes in endoscopic retrograde pancreatography (ERP) and exocrine function evaluated by ST was 74%. In patients with calcified CP, 81% had parallel results between ERP and the ST, but in noncalcified CP, 47% had parallel results. In patients with severe or moderate exocrine insufficiency demonstrated by ST, abnormally low levels were observed in 63% by N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA) test, 61% by fecal chymotrypsin test (FCT), and 44% by pancreatic amylase (PA). In patients with normal exocrine function demonstrated by ST, abnormally low levels were observed in 28% by BT-PABA test, 28% by FCT, and 10% by PA. A combination assay of BT-PABA test, FCT, and PA improved the specificity for diagnosing CP but not the sensitivity. PMID- 9361096 TI - Diagnosis of chronic pancreatitis using noninvasive tests of exocrine pancreatic function--comparison to duodenal intubation tests. AB - The diagnosis of chronic pancreatitis usually is based on imaging studies, pancreatic function tests, and the presence of characteristic clinical features. In Japan, diagnostic criteria for chronic pancreatitis were established in 1983 and revised in 1995. Under the new criteria, the secretin test (a duodenal intubation test) and the combination of noninvasive tests, N-benzoyl-L-tyrosyl-p aminobenzoic acid (BT-PABA) and fecal chymotrypsin (FCT), have been recommended for evaluating exocrine pancreatic function in patients with chronic pancreatitis. In the present study, the diagnostic value of these two noninvasive tests was compared to the secretin test. Although noninvasive tests are less sensitive and specific for determining exocrine pancreatic impairment than the secretin test, greater reliability for diagnosing chronic pancreatitis can be obtained by performing the BT-PABA and fecal chymotrypsin tests simultaneously. Combining BT-PABA and FCT is easy and useful and should be performed at least twice to obtain reliable results. PMID- 9361097 TI - Transcontinental shipping of pancreatic islets for autotransplantation after total pancreatectomy. AB - Islet autotransplantation prevents diabetes in some patients after total pancreatectomy. Pancreatectomy is done at most hospitals but islets are prepared at only a few centers. We report a case in which the pancreas was sent to a laboratory half a continent distant from the operative site, and islets were prepared and returned to the original hospital for autotransplantation 16 h after resection. At 10 months posttransplantation, the patient is normoglycemic and insulin independent, with an appropriate insulin secretion in response to glucose. Endocrine function can be retained after pancreatectomy even if the islets are isolated at a remote laboratory, and autotransplantation could be offered to patients without the need to travel. This outcome implies that the typical handling and processing of a pancreas destined to yield an islet allograft should not prevent the recovery of a sufficient number of viable beta cells to establish insulin independence in type 1 diabetic recipients. PMID- 9361098 TI - Osmotic cell swelling alkalinizes acidic cellular compartments of pancreatic islet and RINm5F cells. PMID- 9361099 TI - Carcinoma of the lung in Okinawa, Japan: with special reference to squamous cell carcinoma and squamous metaplasia. AB - In Okinawa, a subtropical island in southern Japan, squamous cell carcinoma (SCC), especially the well-differentiated form, is prevalent, while this form is relatively rare in both the mainland and other countries (e.g. United States of America). More patients with SCC from Okinawa, moreover, were positive for human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) (79%), and harbored HPV types 6, 16 and 18, in combination. On the other hand, less than 30% of the mainland patients were positive for HPV DNA by PCR. Those patients who were positive all harbored only one HPV type. Furthermore, in Okinawa, there were a significant number of cases with adenosquamous carcinoma, and they too were positive for HPV DNA. The SCC and the adenocarcinoma cells adjacent to the SCC component in these cases were also positive for HPV DNA, and such adenocarcinoma cells were enlarged in size with relatively wide cytoplasm. The authors postulate that HPV infects adenocarcinoma cells and changes them to enlarged cells, followed by squamous metaplasia. In this report, HPV DNA was transfected to adenocarcinoma cells (cultured cell lines) and this showed that HPV causes squamous metaplasia. In addition, aberrant expression of p53 was demonstrated in a large number of the SCC cases in Okinawa. The enlarged adenocarcinoma cells adjacent to the SCC components in adenosquamous carcinomas also showed aberrant expression of p53. The recent advances in the studies of anti-oncogenes, p53, etc. and oncogenes are outlined. It is to be noted that the molecular mechanisms of carcinogenesis in the lung have been studied in general, classifying lung tumors into two groups, namely, small cell carcinoma (SCLC) and non-small cell carcinoma (NSCLC). However, because human lung cancer is represented by a wide variety of histologic types, molecular genetic studies according to a more detailed histological subclassification is needed. PMID- 9361100 TI - S-100 protein is a differentiation marker in thyroid carcinoma of follicular cell origin: an immunohistochemical study. AB - S-100 protein, a dimer of S-100 alpha and S-100 beta subunits (S-100 alpha and S 100 beta), is widely distributed in human tissue, and several papers describing S 100 protein expression in follicular cells of the thyroid have been published. In the present study, 105 cases of thyroid carcinoma (of which 96 were papillary, four follicular, two undifferentiated, and three medullary) were analyzed immunohistochemically for the expression of S-100 protein, S-100 alpha, S-100 beta, and thyroglobulin. In papillary carcinoma, 188 lesions were studied and classified into well differentiated types (56 papillary, 45 follicular) and poorly differentiated types (41 trabecular, four solid, eight squamoid, three tall, and one insular), because the histological structure of each tumor was heterogeneous. The percentage of lesions which expressed positively for S-100 protein and S-100 alpha, respectively, according to type were: papillary, 96 and 99%; follicular, 96 and 100%; trabecular, 95 and 100%; solid, 50 and 50%; squamoid, 50 and 75%; and tall, 33 and 100%. The insular type was negative for both. For papillary carcinoma, well differentiated lesions showed stronger S-100 alpha expression than poorly differentiated lesions. S-100 alpha expression was weaker in follicular and undifferentiated carcinoma than in papillary carcinoma. Medullary carcinoma also expressed S-100 alpha. S-100 beta was positive in lesions that expressed S-100 alpha strongly. Expression of S-100 protein and S 100 alpha protein correlated with thyroglobulin synthesis in the follicular cells. It was concluded that S-100 protein, mainly S-100 alpha, exists in thyroid follicular cells, that it exists in higher quantity in most of the well differentiated lesions but in lower quantity in poorly differentiated or undifferentiated lesions, and that S-100 protein, especially S-100 alpha, is a differentiation marker in carcinoma of thyroid follicular cell origin. PMID- 9361101 TI - Giant cell tumor of bone: frequent actin immunoreactivity in stromal tumor cells. AB - Although giant cell tumor (GCT) of bone is a well-recognized neoplasm with distinctive clinical and histopathological features, the origin of tumor cells, particularly of mononuclear cells, has not yet been established. An immunohistochemical study was carried out on 11 cases of GCT of bone to examine the cellular natures of stromal mononuclear cells. In all cases, stromal cells were positive for muscle actin (HHF35) or alpha-smooth muscle actin, and in eight of 11 cases, positivity was intense and extensive. The cell margin of osteoclast like giant cells (OGC) was stained positively by muscle actin, in addition to intense and diffuse positive staining of the cytoplasm for KP1 (CD68), whereas alpha-smooth muscle actin exhibited a negative reaction on the OGC. In conclusion, the tumor cells with muscle actin and alpha-smooth muscle actin positivities are not rare but frequently numerous in the GCT of bone; whereas further observation is necessary to elucidate whether the stromal cells exhibit myofibroblastic cell differentiation exactly. PMID- 9361103 TI - Pulmonary hemorrhage and antiglomerular basement membrane antibody-mediated glomerulonephritis after exposure to smoked cocaine (crack): a case report and review of the literature. AB - A case of Goodpasture's syndrome with a negative immunofluorescence examination of the lung biopsy in a 32-year-old man is described. The patient was a 40 cigarettes per day smoker, who had been smoking cocaine (crack) up to 3 weeks before hospital admission. He developed a diffuse alveolar hemorrhage with extremely acute respiratory distress, followed by renal failure with anuria. Transjugular renal biopsy, immunofluorescence and serum antiglomerular basement membrane antibody titer studies confirmed the diagnosis of Goodpasture's syndrome without linear immunoglobulin G deposits as determined by immunofluorescence examination of the alveolar basement membranes. The case illustrates the potentially complex interrelations between an autoimmune disease and exposure to substances with possible antigenic properties, besides the imperative necessity for an early, accurate diagnosis and treatment for the potential for threatening life. Moreover, the association of Goodpasture's syndrome with crack has not been previously reported. PMID- 9361102 TI - Modified formalin and methanol fixation methods for molecular biological and morphological analyses. AB - Several simplified fixation methods were examined to determine their suitability for both molecular biological analyses and morphological study. Fixation with 10% v/v formalin alone at 4 degrees C and containing 5 mmol/L ethylenediamine N,N,N',N'-tetraacetic acid (EDTA) at room temperature preserved significantly more high-molecular-weight DNA than 10% v/v formalin fixation at room temperature. The morphological differences between tissues fixed using these modified formalin fixation methods and conventional 10% v/v formalin fixation were negligible. Of the dehydration fixatives tested, 100% methanol did not cause regional differences due to artificial tissue shrinkage and the morphology of sections prepared by methanol fixation was preserved consistently better than that of acetone- or ethanol-fixed sections. All three dehydration fixatives preserved relatively higher-molecular-weight DNA and RNA, compared with formalin. Cold formalin, formalin containing EDTA at room temperature and 100% methanol are recommended as standard and additional fixatives routine clinicopathological laboratory use. PMID- 9361104 TI - A case of lymphoid interstitial pneumonia in a 3-month-old boy not associated with HIV infection: immunohistochemistry of lung biopsy specimens and serum transforming growth factor-beta 1 assay. AB - The case of a 3-month-old boy with lymphoid interstitial pneumonia (LIP) is reported. He had cough and tachypnea, his weight gain was poor and a chest radiograph showed microgranular shadows in almost all lung areas. Histological investigations revealed severe cellular infiltration by a variety of lymphoid and plasma cells with lymphoid follicle formation in the alveolar walls and also around the bronchioles. Foamy macrophages, a few lymphocytes and exudate filled the alveolar spaces. Epithelial cells lining the air spaces expressed human leukocyte antigen (HLA)-DR. Lymphocytes and macrophages in the alveolar spaces expressed transforming growth factor (TGF)-beta strongly. Serum TGF-beta 1 concentrations were measured eight times during the course of his illness. They exceeded the upper end of the normal range in four samples and were within it in the others. These results suggested that dysfunction of the immune system, especially abnormal expression of HLA-DR in non-immune cells and exaggerated production of TGF-beta played important roles in the pathogenesis of LIP in this patient. PMID- 9361105 TI - Follicular dendritic cell sarcoma complicated by hyaline-vascular type Castleman's disease in a schizophrenic patient. AB - Follicular dendritic cell (FDC) sarcoma is an exceedingly rare neoplasm of unknown pathogenesis. A case of FDC sarcoma complicated by the hyaline-vascular type Castleman's disease occurring in a schizophrenic male is presented. Swelling of the left cervical lymph node appeared in a 44-year-old male schizophrenic who had been medicated with major tranquilizers for 20 years. He had had a history of cervical lymphadenopathy 14 years before, for which a diagnosis of hyaline vascular type Castleman's disease had been made. The present specimen, obtained from the same site, was an enlarged lymph node heavily infiltrated with oval to spindle-shaped atypical cells but was uninvolved at the periphery. The infiltrating cells showed nodular or sheet-like growth, occasionally taking fascicular or storiform patterns. Follicular involvement was also common. Peculiarly, various amounts of small lymphocytes were intermingled with the neoplastic cells. The atypical cells expressed two FDC-specific antigens, DRC-1 and Ki-M4 antigen, together with a few other markers that are shared by FDC, including CD21 and HLA-DR. These findings clearly show the tumor to be FDC sarcoma. In addition, a peculiar fibro-hyalinous change in the lymph follicle, which is compatible with hyaline-vascular type Castleman's disease, was noted at the periphery of the lymph node where neoplastic cells had not infiltrated. Surprisingly, similar hyaline-vascular changes were observed in the previous biopsy taken 14 years ago. Meanwhile, Kaposi's sarcoma-associated herpesvirus, which is often identified from generalized Castleman's disease, was not identified in the present case by polymerase chain reaction study. Thus, this case is unique in two aspects: (i) the overlap of FDC sarcoma with hyaline vascular type follicular changes; and (ii) its occurrence in a schizophrenic patient. PMID- 9361106 TI - Follicular dendritic cell tumor with histiocytic characteristics and fibroblastic antigen. AB - A report is presented of a follicular dendritic cell (FDC) tumor arising in the lymph nodes and inguen of a 55-year-old Japanese female, who had suffered from schizophrenia for 25 years. The left submandibular lymph nodes had completely lost their normal architecture, except for the capsule, due to tumor cell infiltration. Occasional nodular structures resembling epithelioid granulomas, attributable, at least in part, to follicular involvement of tumor cells, were observed. These nodules were composed of epithelioid- or fibroblast-like tumor cells forming interwoven fascicles, to which small lymphocytes were attached. Tumor cells were also scattered in the internodular areas. For more atypical tumor cells, arranged in a sheet-like structure, were present in the inguinal specimen, the tumor cells of which expressed Ki-M4p, CD21, CD35 and other antigens known to be expressed on FDC. Furthermore, they also expressed the monocyte/macrophage antigens, alpha 1-antitrypsin, alpha 1-antichymotrypsin, lysozyme, CD14, CD33, CD68 and Mac387 and fibroblastic antigen. Ultrastructural studies demonstrated lysosomal granules as well as a few desmosomes, indicating the tumor cells possessed fibrohistiocytic and FDC characteristics. PMID- 9361107 TI - Solitary fibrous tumor of the prostate. AB - A case of solitary fibrous tumor of the prostate is reported. A 42-year-old man had been complaining of difficult voiding and constipation for 8 years. Urological and radiological examinations showed a large prostatic mass, and a total cystectomy and prostatectomy were performed. The tumor was 14 x 13 x 11 cm in size, solid with a fibromuscular capsule, and gray-tan in color. Histologically, the tumor was composed of short spindle-shaped and polygonal cells with mild to moderate nuclear atypia, predominantly arranged in the so called 'patternless pattern' in a fibrocollagenous background. Mitoses were occasionally seen. Vascular invasion was also observed. Immunohistochemically, these cells were strongly positive for CD34 and vimentin, and occasionally for desmin. The maximum Ki-67 labeling index of the tumor cells was 4.5%. These findings are consistent with a solitary fibrous tumor. To our knowledge, this is the first report of a solitary fibrous tumor of the prostate in the English medical literature. PMID- 9361108 TI - Malignant fibrous histiocytoma of the cecum: report of a case and review of the literature. AB - Malignant fibrous histiocytoma (MFH) of the gastrointestinal tract is extremely rare. Here we report a case of MFH of the cecum and review other cases of large bowel MFH in the literature. A 64-year-old man had a large tumor mass in the cecum associated with multiple small peritoneal implants. Histologically, most of the lesion showed inflammatory pseudotumor-like appearance; that is, a mixed proliferation of fibroblasts and myofibroblasts loosely arranged in sweeping fascicles or whorled structures and an admixture of chronic inflammatory cell infiltrate. The myofibroblastic nature of the spindle-shaped cells was confirmed by their immunohistochemical and ultrastructural findings. In addition, there was atypical histiocytic cells infiltrate in some areas and marked lymphatic involvement and lymph node metastasis by such histiocytic cells. These features were interpreted as MFH, although it had to be distinguished from inflammatory fibrosarcoma and leiomyosarcoma. The differential diagnosis is discussed here. PMID- 9361109 TI - Cystic pulmonary metastases of endometrial stromal sarcoma of the uterus, mimicking lymphangiomyomatosis: a case report with immunohistochemistry of HMB45. AB - A case of endometrial stromal sarcoma (ESS) showed cystic pulmonary metastases mimicking lymphangiomyomatosis (LAM). A 58-year-old female, who had undergone total hysterectomy for low-grade ESS 16 years previously, had repeated bouts of pneumothorax. Multiple thin-walled cysts in the peripheral lung were revealed by radiological examinations. In an open-lung biopsy specimen, cystic lesions were surrounded by layers of spindle-shaped cells of varying thickness that resembled LAM. However, in addition to subtle histologic differences from LAM, HMB45 (antimelanoma antibody) showed positive in LAM (n = 3), but was negative in ESS (n = 2) and the cystic lesions of this case. Using myogenic markers (desmin and alpha-smooth muscle actin), metastatic ESS could be immunohistochemically differentiated from mesenchymal cystic hamartoma (n = 1). HMB45 immunohistochemistry is useful in the differential diagnosis of cystic pulmonary lesions. PMID- 9361110 TI - Epstein-Barr virus-positive multiple early gastric cancers and dysplastic lesions: a case report. AB - Epstein-Barr virus (EBV) has been implicated as a causal virus of gastric cancer with episomal monoclonality, elevated antibodies and a unique morphologic expression in the early intramucosal stage, but the infection mechanisms have not been demonstrated. EBV has been shown only in the cancerous lesions by the highly sensitive EBV-encoded small RNA in situ hybridization (EBER-ISH) method, not in the dysplastic mucosa adjacent to the cancer. A case is presented of multiple EBV positive gastric cancer and dysplastic epithelium observed in a 52-year-old man. Serial cut sections of the gastrectomy specimen showed four small cancerous lesions, three of which were EBER-positive, and three EBER-positive, minute, non cancerous dysplastic lesions. The three cancerous lesions were intramucosal cancer, with one having minimal submucosal invasion forming a lymphoepithelioma like histology. All of these EBER-positive cancerous and dysplastic lesions showed intense CD8 T-lymphocytic infiltration. There was no such findings in the EBV-negative cancerous lesion. It was concluded that EBV infection may occur in the epithelial cells of atrophic gastric mucosa, and progress to cancer with monoclonal expansion through the EBV-positive dysplastic change. Cytotoxic T lymphocytic reactions can occur even in the dysplastic lesions. Multifocal EBV infection in the gastric mucosa may occur and, if necessary, total gastrectomy is recommended in such a case. PMID- 9361111 TI - Myxopapillary ependymoma of the conus medullaris and filum terminale in the pediatric age group. AB - Myxopapillary ependymoma of the conus medullaris and filum terminale is a relatively common spinal intradural neoplasm in adulthood. However, only a reported 8-12% of such tumors affect this site in children, and the ideal management remains controversial. Three children with myxopapillary ependymomas of the conus medullaris and filum terminale were treated by the author over a 2 year period with an at least 24-month follow-up. These children, ages 7, 8 and 13 years, included 1 male and 2 females. Their salient presentation was an acute exacerbation of chronic lower back pain. The duration of symptoms prior to diagnosis ranged from 16 to 18 months. A preoperative MRI, with and without contrast, was available for every case. All children underwent replacement laminoplasty with gross total tumor resection. Somatosensory evoked potentials were used in all surgeries. An early postoperative MRI of the entire neural axis was available for all cases. No permanent complications were noted. Self catheterization for 6 weeks was required in 1 child with preoperative urinary incontinence. One child received radiation therapy following a recurrence. Clinical and surgical results were compared to the only 2 other reported series (11 patients) addressing this type of tumor in children. Based on this review, the authors propose that: (1) unexplained and intractable lumbar pain in childhood should be thoroughly investigated with an MRI scan: (2) the gross feature of myxopapillary ependymoma allowing for complete resectability appears to be the key prognostic factor; (3) radiotherapy appeared to have no proven value in completely resected tumors in children; (4) postoperative baseline MRI and regular sequential imaging studies are essential for long-term follow-up, and (5) replacement laminoplasties may be of value in preventing future spinal deformities, musculoskeletal pain and allowing for an 'easier' resection in the event of a recurrence. PMID- 9361112 TI - Spinal lipomas in children: outcome of 270 procedures. AB - Spinal lipomas are a common cause of spinal cord tethering. Recently, prophylactic surgical removal of spinal lipomas has been questioned, especially of the conus medullaris. Unfortunately, few statistically significant series have been reported. A total of 213 children with spinal lipomas were operated on at the Children's Memorial Hospital in Chicago, Ill., USA, on whom 270 procedures were carried out between 1975 and 1995. The status of these children was retrospectively reviewed to determine the differences in outcome between patients prophylactically operated on before the onset of symptoms and those operated on after the onset of symptoms. Fifty-five patients presented with a lipoma of the filum terminale and 158 with a lipoma of the conus medullaris. In the filum terminale group, 28 were asymptomatic at the initial operation, and 27 presented with symptoms. Of the asymptomatic children with filum terminale lipomas, none worsened after surgery, and all remained asymptomatic throughout follow-up (mean follow-up: 3.4 years). Benefits were also observed for the symptomatic patients in this group as no cases of further deterioration were noted, and 5 patients returned to normal clinical status. In the conus group, 71 patients were asymptomatic at initial surgery, and 87 presented with symptoms. In the case of conus medullaris lipomas, 9 of the 71 children who were operated on prophylactically, later deteriorated (mean follow-up: 6.2 years) and required a second untethering operation which resolved all symptoms in 4 cases. Thus, 5 of 71 deteriorated, while 66 remained normal (93%) throughout the period of follow up. On the other hand, of the 87 patients operated on after the onset of symptoms, 36 (41%) deteriorated further and required subsequent reoperations. In these 87 children, the final outcome at the end of follow-up (mean follow-up: 6.6 years) showed that 20 (23%) patients had deteriorated compared to initial presentation and 44 (51%) remained at initial clinical baseline, while 23 (26%) improved or returned to normal clinical status. Prophylactic surgery in the case of the asymptomatic infant with a spinal lipoma showed a clear benefit. Good outcome was also observed when surgery was carried out after the onset of symptoms. Prophylactic surgery also had a better general outcome by actuarial calculations when only patients with a follow-up of more than 5 years were considered. Deterioration occurred in 5 (16.7%) of the 30 children with a follow up of more than 5 years, while 25 (83.3%) remained normal. Furthermore, in cases which had prophylactic surgery, there was not only a smaller incidence of deterioration requiring a reoperation, but this group of patients also experienced a longer time interval between initial surgery and the need for reoperation compared to the patients operated on after the onset of symptoms. The authors conclude that spinal lipomas should be operated on as soon as possible on a prophylactic basis, and careful and constant follow-up should be carried out to permit prompt reintervention in cases with deterioration. PMID- 9361113 TI - Split cord malformations of the lumbar region. A model for the neurosurgical management of all types of 'occult' spinal dysraphism? AB - From a group of 84 patients with split cord malformations presenting to our Department between 1976 and 1990, we have selected 47 cases in whom the split cord was confined to the lower dorsal-lumbar region and in whom there were no other dysraphic features such as meningocele, lipoma or dermoid cyst. We have studied these cases of 'pure split cord malformation' in an attempt to decipher its natural history and the effects of surgical procedures designed to untether the spinal cord. We conclude that the 'neuro-orthopaedic syndrome' (which includes lower limb asymmetry, talipes and modest sensory and motor problems) is, in most cases, an inevitable consequence of the abnormal functional anatomy of the split cord and is not due to any mechanical effects of tethering of the spinal cord. Its emergence as a child grows (assuming that it was not obvious at birth) is not influenced by surgery. True neurological deterioration (defined as the loss of a previously established neurological or urological function) is a rarer event. It may occur at any age--including well into adulthood--but in children the average age at presentation is 6.8 years (range 2 years 9 months to 11 years). It is due to the mechanical effects of tethering of the spinal cord and is more likely to be arrested than improved by surgery. 'True' deterioration did not occur in any of our cases who had undergone prophylactic untethering of the spinal cord and we have concluded, therefore, that surgery has a role in the prevention of late neurological problems affecting the lower limbs and bladder. Surgery to untether the spinal cord will not, however, have any affect upon the emergence of the neuro-orthopaedic syndrome. PMID- 9361114 TI - A modern analysis of intracranial tumors of infancy. AB - OBJECTIVE: The management results of pediatric brain tumors should have improved with progress in neurosurgery, intra- and perioperative care, and adjunctive therapy. We assessed the outcomes of 88 consecutive children under 2 years of age with brain tumors managed in the modern era, primarily by two neurosurgeons, and compared the results within the study group over time and to historical controls. METHODS: Medical records were reviewed for diagnosis, location, surgery, surgical morbidity and mortality, adjunctive therapy, and long-term results. Outcomes were available on all 88 patients. RESULTS: Primitive neuroectodermal tumors, astrocytomas, ependymoma, and choroid plexus papillomas in descending order of frequency accounted for two thirds of tumors. Supratentorial location predominated (60%), although in the 1- to 2-year group, there was a slight majority of infratentorial tumors. Surgical mortality and immediate morbidity were 9 and 26%, respectively, with substantial improvements in the last half of the series (2 and 16% with long-term morbidity of 11%). 53 of 88 (60%) of our patients are alive, and all children treated since January 1, 1994, except for 1 operative death, remain alive. CONCLUSION: Children less than 2 years of age remain a multidisciplinary challenge. Improved neuroimaging, surgical and pediatric intensive care management, and neuro-oncological care seems to have improved outcome both with respect to tumor control and neurological function. Aggressive surgery is possible with a good outcome generally expected. Hopefully this will set the stage for either surgical cure in children with benign tumors or combined surgical and adjunctive cure in patients with malignant tumors. PMID- 9361115 TI - Methyl methacrylate cranioplasty in children: long-term results. AB - The long-term outcome of 75 children who underwent methyl methacrylate cranioplasty over a 15-year period is presented. Forty-two patients underwent cranioplasty for posttraumatic skull defects and 33 for nontraumatic causes. Within 8 years following initial cranioplasty procedure, a total of 17 (23%) complications occurred. Several factors correlated with the development of complications, including postoperative radiotherapy, the size of the defect, involvement of the frontal sinus, and the presence of prior infection. The authors currently recommend avoiding methyl methacrylate cranioplasty in selected patients who have received postoperative radiation therapy, in patients with large cranial defects, involvement of the frontal sinus, or any history of prior infection. PMID- 9361116 TI - Astrocytoma and pineoblastoma arising sequentially in the fourth ventricle of the same patient. Case report and molecular analysis. AB - The sequential appearance of two different brain tumors in the same patient without intervening radiation or chemotherapy is a rare event, most often seen in hereditary cancer syndromes. We present one such case of sequential tumors, along with their molecular analysis. A 17-year-old male presented with a pilocytic astrocytoma arising in the fourth ventricle at the pontomedullary junction. Six and one half years later, a pineoblastoma was discovered in the fourth ventricle, rostral to the first tumor site. Both tumors were treated by gross-total surgical resection. Following resection of the pineoblastoma, the patient underwent craniospinal irradiation and systemic chemotherapy. Single-strand conformation polymorphism analysis showed that the patient had neither a germ-line mutation nor a somatic tumor mutation in the p53 tumor suppressor gene. Coupled with the lack of a family history of cancer, these data suggest that these were not manifestations of Li-Fraumeni syndrome, but rather two sporadic tumors which arose via a p53-independent mechanism. PMID- 9361117 TI - Posterior circulation aneurysms in a child: clipping of one leads to spontaneous thrombosis of the other. AB - Multiple intracranial aneurysms in children are infrequent. This case involves an 11-year-old girl who presented with subarachnoid hemorrhage with posterior cerebral and superior cerebellar artery aneurysms. Initially, she underwent clipping of the posterior cerebral artery aneurysm. Four months later, she returned for clipping of the other aneurysm, at which time it was found to have completely thombosed. The literature contains 4 other cases of spontaneous thrombosis of intracranial aneurysms in children, but only one aneurysm < 25 mm in size is described. The clinical, surgical, and radiological features of this case and a detailed literature review are presented. PMID- 9361118 TI - Middle cranial fossa arachnoid cysts that come and go. Report of two cases and review of the literature. AB - Arachnoid cysts are relatively common lesions encountered in neurosurgical practice. While arachnoid cysts are most commonly observed to remain of fixed volume over time, little is actually known about their natural history and optimal method of treatment. We present 2 young children with middle fossa arachnoid cysts. In 1 child, the cyst enlarged over time, prompting neurosurgical intervention. However, in the other child, the cyst resolved spontaneously without intervention. The child whose cyst enlarged underwent cyst wall fenestration and cyst-peritoneal shunting. For the child whose arachnoid cyst disappeared without treatment, there was no history of trauma or antecedent headache. These 2 cases serve to illustrate in a single report that middle fossa arachnoid cysts can be dynamic in nature, with some growing in size while others spontaneously resolving. In both cases presented, the temporal lobe on the affected side was compressed by the large cyst. Following treatment or spontaneous resolution of the cyst, the temporal lobe reexpanded, suggesting a normal volume of temporal lobe, and not temporal lobe agenesis. In asymptomatic patients with moderate-sized arachnoid cysts such as the ones demonstrated in these case reports, we suggest close follow-up with serial imaging before deciding on a final treatment plan. PMID- 9361119 TI - Child abuse. PMID- 9361120 TI - Controlled drug trials in photodermatoses. AB - While clinical drug trials in photodermatoses may be complex because of the fickleness of these disorders in their reproducibility following ultraviolet exposure, such investigations require the same general principles of careful design as those in any other disciplines. The ideal clinical trial in photodermatology is both randomized and double-blind. Precise diagnostic terminology and monitoring of sun exposure must be employed. Polysulphone film badges are the most suitable personal dosimeters to date for these studies. Assessment of itching and discomfort may be reliably performed by the use of a visual analogue scale. Symptoms may also be assessed, but less precisely, by means of a diary record. Only by the use of controlled trials, however, will anecdotal dogma be prevented from inappropriately entering the therapeutic armamentarium of the dermatologist who manages such light sensitive conditions. PMID- 9361121 TI - Phototoxicity to sulphonamide-derived oral antidiabetics and diuretics: investigations in hairless mice. AB - The oral antidiabetics glibenclamide, glipizide, glymidine, tolazamide and tolbutamide and the diuretics bemetizide, bendroflumethiazide, benzylhydrochlorothiazide, bumetanide, butizide, furosemide, hydrochlorothiazide, hydroflumethiazide and trichlormethiazide were investigated for phototoxic effects in hairless mice. The back of the animals (hr/hr-c3H/TifBom) was covered with Duoderm dressing, and at the site of two punched out holes 0.05 ml of the test substances at 0.25 mol/l concentration and the solvent alone as control were injected intradermally, respectively. Both test and control sites were irradiated with 6-12 J/cm2 of longwave UVA light from a "Bluelight 2000" apparatus (Honle, Martinsried, Germany). Skin reactions were read at 24 and 48 h. Compared to the solvent alone, all of the test substances induced reactions (necrosis or oedema)- most frequently seen by macroscopic and histologic investigation and by measurements with a thickness gage. Injection of the test substance or solvent alone without or with subsequent UVA irradiation, as well as UVA alone, did not induce measurable skin changes in this model. Three oral antidiabetics and four diuretics, not yet described to induce photosensitivity in vitro nor in vivo, were detected as potential photosensitizers using our animal model. PMID- 9361122 TI - Psoralen-fatty acid adducts activate melanocyte protein kinase C: a proposed mechanism for melanogenesis induced by 8-methoxypsoralen and ultraviolet A light. AB - Diacylglycerol, a protein kinase C activator, induces and enhances melanogenesis in vitro and in vivo, providing evidence that melanogenesis may be a protein kinase C-mediated process. Melanogenesis is also induced by ultraviolet A radiation and potentiated by a combination of 8-methoxypsoralen and ultraviolet A radiation. We incubated cultured normal human melanocytes with 8-methoxypsoralen, irradiated the cells with ultraviolet A radiation, and detected formation of 8 methoxypsoralen-phospholipid photoadducts. The 8-methoxypsoralen-phospholipid photoadducts isolated from melanocytes were substrates for phospholipase A2 to generate 8-methoxypsoralen-fatty acid adducts. We found that 8-methoxypsoralen fatty acid photoadducts prepared in vitro could be substituted for diacylglycerol to activate protein kinase C in a cell-free system. We propose that 8 methoxypsoralen-fatty acid adducts activate protein kinase C to potentiate ultraviolet A radiation-induced melanogenesis. This proposal links melanogenesis mediated by protein kinase C with that induced by a combination of 8 methoxypsoralen and ultraviolet A radiation. PMID- 9361124 TI - Clinical drug photosensitivity. A retrospective analysis of reports to the Norwegian Adverse Drug Reactions Committee from the years 1970-1994. AB - Adverse drug reactions reported to the Norwegian Medicine Control Authority from 1970 to 1994 were analyzed, especially with regard to cutaneous reactions and photosensitization. In the time period, almost 13,000 unwanted side effects were reported. Of these, 799 reports involved the skin and appendages, of which 64 reports (8%) were classified as photosensitivity reactions. Tetracyclines, diuretics, antihypertensive agents, and urologicals were the drugs that most often caused photosensitivity reactions. In addition, a number of uncommon photosensitizing drugs were reported. The risk for photosensitization is discussed on the basis of experimental data and the prescription rates of these substance. PMID- 9361123 TI - Bath PUVA--an investigation of the distribution of trioxsalen (TMP) and 8 methoxypsoralen (8-MOP) in bathwater. AB - Trioxsalen (TMP) bath PUVA avoids the side effects of nausea and headache associated with oral 8-methoxypsoralen (8-MOP) treatment and allows shorter irradiation times that can be advantageous in some patients. However we noted that a number of patients developed unusual patterns of phototoxic burning. We thought that this was related to an uneven distribution of the TMP in the bathwater and for this reason, a study of bath water TMP concentrations achieved using different TMP preparations was undertaken. The distribution of 8-MOP in an 8-MOP bath was also measured for comparison. Our results confirm that an uneven distribution of TMP is achieved using TMP capsules or suspension and would explain our observed patterns of burning. With an ethanolic solution of TMP, or the commercial equivalent Tripsor, or with Puvasoralen-8 (an 8-MOP preparation), a homogeneous psoralen distribution is achieved, and they are therefore preferable for use in bath PUVA. PMID- 9361125 TI - Measurement of suberythema UVA radiation effects on skin by 31P magnetic resonance spectroscopy. AB - 31P magnetic resonance spectroscopy (MRS) scans were obtained from the same anatomical location in four healthy Caucasian individuals before and after 1/2 MED UVA radiation. Suberythema UVA radiation induced in skin production of phosphomonoesters, phosphodiesters, and also depleted phosphocreatine and adenosine triphosphate (ATP). This data seems to indicate that 31P MRS is a sensitive enough technique to detect UVA induced changes in skin phosphometabolites. Furthermore, this data also appears to indicate that suberythema UVA radiation and dexamethasone induce in skin nearly identical pharmacodynamic effect. PMID- 9361126 TI - Use of dermal equivalent and skin equivalent models for identifying phototoxic compounds in vitro. AB - Phototoxicity inducing in vivo photoirritation, a reversible inflammatory reaction of the skin after chemical contact and UVA radiation exposure, is increasingly observed as a side effect associated with the use of both cosmetics and systemic drugs. In order to systematically screen for the phototoxic potential of new compounds, we propose two three-dimensional models suitable for in vitro testing: a dermal equivalent (DE) and a skin equivalent (SE) model. The DE model includes a collagen-glycosaminoglycans-chitosan porous matrix populated by normal human fibroblasts. The SE model is made by seeding normal human keratinocytes onto the DE, leading to a fully differentiated epidermis. The objectives of this pilot study are: 1) to compare the deleterious effects of UVA radiation on the two models and 2) to evaluate to what extent the in vitro results can predict the in vivo phototoxicity caused by well-known photoirritant compounds, included in the COLIPA validation phototoxicity reference chemical list. Dilutions of thiourea, sulisobenzone, promethazine, chlorpromazine and tetracycline were applied (20 microliters) onto DEs and SEs (n = 6) and incubated for 1 h (or 15 h) at 37 degrees C. Irradiated samples received 3 J/cm2 UVA. The 24 h post-irradiation residual cellular viability was measured using the MTT test on treated and untreated tissues and IL-1 alpha release measurement in collected SE culture media. A concordance in terms of photoirritant/non-photoirritant was obtained between the in vivo data and the in vitro results, suggesting that the DE and the SE models could be integrated, after a complete validation study, into a protocol for in vitro testing of the photoirritant potential of new molecules. PMID- 9361127 TI - Microfluorometry using fluorescein diacetate reflects the integrity of the plasma membrane in UVA-irradiated cultured skin fibroblasts. AB - The damaging effect of long-wave ultraviolet radiation (UVA) on the plasma membranes of cultured human skin fibroblasts was evaluated by cytofluorometry performed after vital staining with fluorescein diacetate. The damage was associated with lipid peroxidation, as shown by accumulation of malondialdehyde and 4-hydroxyalkenals; such accumulation was induced by a UVA dose of only 8 J/cm2. Pretreatment with the effective membrane peroxidation inhibitor alpha tocopherol (added in the form of alpha-tocopherol succinate) or the singlet oxygen quencher beta-carotene protected the cells from membrane damage. Further, depletion of intracellular glutathione by exposure of the cells to buthionine sulfoximine, an inhibitor of gamma-glutamylcysteine synthetase aggravated the membrane-damaging effects. The results confirm the photodynamic effects of UVA, which presupposes the excitation of endogenous photosensitizer(s) and the production of reactive oxygen species. The present results indicate that this method of detection of alterations in plasma membrane stability may be highly suitable for studying various photobiological phenomena and for use as a model for testing substances that could protect skin from UVA damage. The trypan blue exclusion test proved to be too insensitive to detect these changes. PMID- 9361128 TI - Flow cytometry study of the role of superoxide anion and hydrogen peroxide in cellular photodestruction with 5-aminolevulinic acid-induced protoporphyrin IX. AB - Flow cytometry was used to investigate the participation of reactive oxygen species, other than singlet oxygen, in the cytotoxic effect of photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in vitro in A-431 squamous cell carcinoma (SCC) cells and human skin fibroblasts (HSF). We used propidium iodide to determine cellular cytotoxicity, hydroethidine to measure intracellular superoxide anion (O2-) and dihydrorhodamine 123 to assess intracellular hydrogen peroxide (H2O2) content. Our data support the importance of the incubation time with ALA in the selectivity of PDT with ALA against SCC cells, inducing minimum damage on normal HSF. Photoradiation mortality curves of the response of these cell lines to ALA-induced PpIX photosensitization correlated with the extent of photosensitizer accumulation. Intracellular O2- production correlated with cell death, increasing both in a light dose-dependent fashion in ALA treated cells. This correlation was not observed with H2O2-intracellular production. These results suggest the effectiveness of PDT with ALA in vitro in SCC, the significant participation of O2- in its phototoxic mechanism, and the usefulness of flow cytometry in the study of the cytotoxic effect of ALA-induced PpIX PDT. PMID- 9361129 TI - Topical or oral administration with an extract of Polypodium leucotomos prevents acute sunburn and psoralen-induced phototoxic reactions as well as depletion of Langerhans cells in human skin. AB - Sunburn, immune suppression, photoaging, and skin cancers result from uncontrolled overexposure of human skin to solar ultraviolet radiation (UVR). Preventive measures, including photoprotection, are helpful and can be achieved by topical sunscreening agents. Polypodium leucotomos (PL) has been used for the treatment of inflammatory diseases and has shown some in vitro and in vivo inmunomodulating properties. Its beneficial photoprotective effects in the treatment of vitiligo and its antioxidant properties encouraged us to evaluate in vivo the potentially useful photoprotective property of natural extract of PL after topical application or oral ingestion. Twenty-one healthy volunteers [either untreated or treated with oral psoralens (8-MOP or 5-MOP)] were enrolled in this study and exposed to solar radiation for evaluation of the following clinical parameters: immediate pigment darkening (IPD), minimal erythema dose (MED), minimal melanogenic dose (MMD), and minimal phototoxic dose (MPD) before and after topical or oral administration of PL. Immunohistochemical assessment of CD1a-expressing epidermal cells were also performed. PL was found to be photoprotective after topical application as well as oral administration. PL increased UV dose required for IPD (P < 0.01), MED (P < 0.001) and MPD (P < 0.001). After oral administration of PL, MED increased 2.8 +/- 0.59 times and MPD increased 2.75 +/- 0.5 and 6.8 +/- 1.3 times depending upon the type of psoralen used. Immunohistochemical study revealed photoprotection of Langherhans cells by oral as well as topical PL. The observed photoprotective activities of oral or topical PL reveal a new avenue in examining the potentially useful field of systemic photoprotection and suggests that PL can be used as adjunct treatment and can make photochemotherapy and phototherapy possibly safe and effective when the control of cutaneous phototoxicity to PUVA or UVB is a limiting factor in such phototherapies. PMID- 9361130 TI - Cyclosporin A therapy for severe solar urticaria. AB - Solar urticaria is characterized by itching weals that occur a few minutes after exposure to visible or ultraviolet light. The symptoms may sometimes restrict normal daily life. Treatment is difficult in more severe cases. We describe one patient with solar urticaria who was successfully treated with cyclosporin A. The patient had first been treated with antihistamine, PUVA and chloroquine phosphate without effect. Cyclosporin was given in a dose of 4.5 mg/kg body weight/day. Phototesting before, during and after treatment showed a decreased light sensitivity to UVA, UVB and visible light during cyclosporin treatment compared with phototesting before therapy. The patient could be out in the sun for at least 1 h with minimal urticaria during cyclosporin therapy compared with only a few minutes previously. However, 1-2 weeks after cyclosporin therapy was discontinued, skin symptoms returned. Cyclosporin therapy is a possible treatment in severe cases of solar urticaria where other treatments have failed, especially in countries where treatment is necessary only for a few months during summer. PMID- 9361131 TI - The standard erythema dose: a new photobiological concept. PMID- 9361132 TI - An open trial of topical urocanic acid for the treatment of stable plaque psoriasis. PMID- 9361133 TI - Phylogenetic analysis of thermal acclimation of the glycolytic enzymes in the genus Fundulus. AB - Physiological acclimation that alters enzyme activity can compensate for the effect of temperature on function and may be achieved by altering enzyme concentration. This study uses phylogenetic analyses to investigate the evolutionary history of and to test several hypotheses about acclimation responses among all the glycolytic enzymes. These hypotheses are that (1) acclimation increases enzyme concentration at lower temperatures to compensate for reduced activity; (2) equilibrium enzymes tend to show acclimation responses; and (3) acclimation responses are more common in species whose populations experience either large temporal or geographical temperature variations. Using maximal activities as indices of enzyme concentration, the presence of acclimation responses in all the glycolytic enzymes in the heart ventricle was determined for five species in the teleost genus Fundulus. Three of these species are distributed along the steep thermal cline of the North American Atlantic coast, and thus these species experience both seasonal and geographical variation in temperature. The other two species are found in the Gulf of Mexico and experience seasonal variation similar to the Atlantic species but no geographical variation in temperature. Two Atlantic coast species, Fundulus heteroclitus and Fundulus majalis, have unique derived acclimation responses. No derived acclimation responses occur in the Gulf species. A conserved response in hexokinase was observed within one subgenus comprising both Atlantic and Gulf species. In F. heteroclitus, enolase responded to acclimation, and in F majalis, aldolase, triphosphate isomerase, and lactate dehydrogenase had acclimation responses. These enzymes are equilibrium enzymes, and the concentrations of all of them increase at lower temperatures, which would compensate for the effect of temperature on enzyme activity. The compensatory changes all occur in the Atlantic species and may be a mechanism for species to expand their ranges. These data suggest that physiological acclimation is evolutionarily labile. PMID- 9361134 TI - Apparent absorption efficiency and gut morphometry of wood mice, Apodemus sylvaticus, from two distinct populations with different diets. AB - Interpopulation variation in the diet of the wood mouse, Apodemus sylvaticus, is well documented. In this study, we examined the gut morphology and apparent absorption efficiencies of two populations of wood mice whose diet in the field was known to differ. One population inhabited sand dunes, where food availability was relatively low and the diet was dominated by invertebrates. The other population lived in deciduous woodland, with greater food availability and a diet consisting primarily of seeds. Wood mice from the woodland had longer small intestines and total digestive tract lengths than mice from the sand dunes. However, these differences had no effect on the apparent absorption efficiencies of dry mass or energy when the mice were fed mealworms, wheat grain, or All-Bran diets (apparent energy absorption efficiencies of 88%, 89%, and 65%, respectively). The population differences in gut morphometry may be linked to different resource availabilities at the two field sites. PMID- 9361135 TI - Nitrogen and energy requirements of the North American porcupine (Erethizon dorsatum). AB - We measured nitrogen and energy requirements in adult North American porcupines (Erethizon dorsatum) fed three experimental diets differing primarily in crude protein content. Porcupines ingested 497.3-865.4 kJ kg-0.75 d-1, and there was no significant loss of body mass on any dietary treatment. Individuals maintained nitrogen balance on a total nitrogen intake of 389.4 mg N kg-0.75 d-1. The true digestibility of nitrogen was high (88%) but within the range for eutherians. We found metabolic fecal nitrogen to be 0.92 mg N g-1 dry matter intake and endogenous urinary nitrogen to be 223 mg N kg-0.75 d-1. The low value of metabolic fecal nitrogen found for porcupines affects the dry matter intake required for nitrogen balance, and it may allow these animals to exploit nitrogen poor diets. PMID- 9361136 TI - Ecto-ATPase activity of vertebrate blood cells. AB - Ecto-ATPase activity was measured for red blood cells, white blood cells, and whole blood from a variety of vertebrates. A large range of red blood cell ecto ATPase activity was observed; for example, at 10 degrees C, red blood cells from a catastomid fish (Catostomus macrocheilus) and a newt (Taricha rivularis) had activities of 56 +/- 9 and 25,000,000 +/- 14,000,000 pmol ATP per 10(6) red blood cells per hour, respectively (mean +/- SD). Several control experiments verified that the measured ATPase activity was not the result of intracellular ATPases released due to cell damage or lysis nor due to the release of intracellular nucleoside triphosphate or uptake of extracellular ATP. Red blood cell ecto ATPase activity was relatively low within the teleosts, was high within the reptiles, and had the greatest range and single highest value within the amphibians. Within the endotherms, avian red blood cell ecto-ATPase activities were greater than mammalian red blood cell ecto-ATPase activities, which were the lowest for all vertebrates examined. The lowest ecto-ATPase activities measured were for human and skunk red blood cells, which had activities of 13 +/- 1 and 11 +/- 2 pmol ATP per 10(6) red blood cells per hour, respectively, at 35 degrees C. Ecto-ATPase activity was measured in white blood cells of several vertebrate species and appeared generally high and less variable than red blood cell ecto ATPase activity. Measured whole blood ecto-ATPase activity showed a range of three orders of magnitude and correlated positively with red blood cell ecto ATPase activities. Ecto-ATPase activity was also determined for red blood cells from fetal, 1-3 d old neonatal, and pregnant garter snakes (Thamnophis elegans); these activities were not significantly different from the activity of red blood cells from nonpregnant adult females. Overall, the data from the present study demonstrate a wide range of red blood cell and whole blood ecto-ATPase activities among vertebrates and include some of the highest ecto-ATPase activities reported to date. PMID- 9361137 TI - Thermal sensitivity of growth and feeding in Manduca sexta caterpillars. AB - We explore how the thermal sensitivity of organismic performance emerges from the thermal sensitivity of the underlying component processes involved, using growth and feeding of Manduca sexta caterpillars as a model system. We measured thermal performance curves for the short-term rates of growth, consumption, protein (casein) digestion, amino acid (methionine) uptake, and respiration in fifth instar caterpillars over a biologically realistic temperature range from 14 degrees to 42 degrees C. Growth and consumption rates increased between 14 degrees and 26 degrees C, reached a maximum value near 34 degrees C, and declined rapidly above 38 degrees C. In contrast, protein digestion rate and respiration rate increased monotonically over the entire temperature range, and amino acid uptake rate increased with temperatures up to 38 degrees C and then leveled off between 38 degrees and 42 degrees C. These results suggest that the shape and position of the thermal performance curve for growth rate--in particular the maximum at 34 degrees C and rapid decline above 38 degrees C--was most closely correlated with the thermal sensitivity of consumption rate; the declining growth performance above 38 degrees C was not associated with declines in digestion or uptake rates or with accelerated respiration rates at these temperatures. PMID- 9361138 TI - The influence of feeding on oxygen consumption and nitrogen excretion in the Antarctic nemertean Parborlasia corrugatus. AB - The large nemertean Parborlasia corrugatus is common in nearshore benthic marine habitats around Antarctica, where it is an important predator and scavenger. Oxygen consumption and nitrogen excretion rates in worms freshly sampled from the field were low but similar to those reported for other polar marine ectotherms. Nitrogen was excreted primarily as ammonia (87%), with smaller amounts of urea (4%) and amines (9%). The O:N atomic ratio was low (10.4), indicating that free or protein-derived amino acids were important metabolic substrates. When worms were fed at ration levels ranging from 20% to 110% of body mass, both oxygen demand and ammonia excretion increased after feeding in a classic specific dynamic action response. Peak postprandial oxygen consumption was low (range, 1.5 2.6 times the prefeeding rate), and the duration of the specific dynamic action was unusually long (> 30 d). Both the energy used and the nitrogen excreted in the specific dynamic action scaled with meal size, although the fractions of ingested carbon and nitrogen used or lost were both very low, probably because of the large ration levels. We conclude that Parborlasia corrugatus has only a limited ability to increase its metabolic rate following a meal and, as a result, takes many days to process that meal fully. PMID- 9361139 TI - Extracellular carbonic anhydrase activity and carbonic anhydrase inhibitors in the circulatory system of fish. AB - Carbonic anhydrase activity in the extracellular fluid of lower vertebrates is considered to be minimal, either because of the absence of carbonic anhydrase or because of the presence of naturally occurring inhibitors. The presence of carbonic anhydrase activity and circulating inhibitors was measured in plasma and subcellular fractions of gill tissue in elasmobranchs and teleosts. Plasma carbonic anhydrase activity was confirmed in the former but in extremely low amounts, especially compared with activity in red cells. The activity was correlated with plasma iron concentration and red cell hemolysis, which suggests that it is a byproduct of endogenous hemolysis during red cell turnover. A subcellular fraction of dogfish gills rich in microsomes contained significantly higher carbonic anhydrase activity than previously found in teleosts, making elasmobranchs the only aquatic lower vertebrates to possess putative basolateral membrane-associated carbonic anhydrase in the gill vasculature. It is suggested that branchial membrane-associated carbonic anhydrase is correlated more with a pH and/or CO2-sensitive ventilatory drive than with the maintenance of resting CO2 excretion. The occurrence and effectiveness of plasma carbonic anhydrase inhibitors were highly species-specific, with the salmonids having the most potent inhibitor. Cross-reactivity of inhibitor to red cell carbonic anhydrase appeared to be related to phylogenetic proximity. Selection for the presence of carbonic anhydrase inhibitors in fish plasma appears to be the result of multiple physiological pressures, including preservation of red cell intracellular pH, ventilatory control, and red cell fragility. PMID- 9361140 TI - Low cost of locomotion in the banded Gecko: a test of the nocturnality hypothesis. AB - This study tested the hypothesis that there has been an evolutionary increase in locomotor performance capacity at low temperature in nocturnal lizards. Nocturnal lizards are often active at low and suboptimal body temperatures. An evolutionary decrease in the minimum cost of locomotion could increase endurance capacity at low temperature, partially offsetting the thermal handicap of nocturnality. In support of the nocturnality hypothesis, we discovered that minimum cost of locomotion of a nocturnal gecko, Coleonyx variegatus (4.2 g), was only 58% of the minimum cost of locomotion of Phrynosoma douglassii, a diurnal lizard (4.5 g). As a result, maximum aerobic speed was 2.3 times as great in the nocturnal lizard compared to the diurnal lizard. By using the method of phylogenetically independent contrasts at the species level, we showed that the relationship between mass and minimum cost of locomotion in diurnal lizards was similar to that of the ahistorical standard allometry and that low minimum cost of locomotion in geckos represents a significant evolutionary change from the ancestral diurnal pattern. The decrease in the minimum cost of locomotion concordant with the evolution of nocturnality suggests that geckos evolved a greater capacity for sustained locomotion at low temperature. PMID- 9361141 TI - Cold tolerance in hatchling painted turtles (Chrysemys picta): supercooling or tolerance for freezing? AB - We studied tolerance for cold in hatchling painted turtles (Chrysemys picta) from Lake Metigoshe, Bottineau County, North Dakota, to determine whether neonates in populations near the northern limit of distribution rely on a tolerance for freezing or on a capacity for supercooling to survive their first winter of life. We placed hatchlings individually into artificial hibernacula constructed in jars of damp, loamy sand and then cooled the jars to approximately -0.45 degrees C, which was below the equilibrium freezing point for water held by the sand but above that for body fluids of the neonatal turtles. A piece of ice next was placed on the surface of the sand in each jar to induce freezing of the soil water. After the soil water had frozen to an equilibrium, the temperature in the jars was lowered by 1 degrees C/d to minima averaging -2.5 degrees C, -4.5 degrees C, -6.5 degrees C, and -10.5 degrees C in different treatments. These temperatures were maintained for varying periods, so that animals in each treatment were exposed to temperatures below the equilibrium freezing point for their body fluids for a total of 11 d. Thirty of 32 hatchlings survived exposure to -2.5 degrees C; 24 of 32 survived at -4.5 degrees C; 14 of 32 withstood -6.5 degrees C; and 7 of 32 tolerated -10.5 degrees C. Freezing exotherms were detected in temperature profiles for turtles that succumbed but not in those for hatchlings that survived. Thus, the ability of hatchlings to withstand subzero temperatures for extended periods apparently requires that they avoid freezing. Although other workers contend that tolerance for freezing is the key to survival over winter by hatchling painted turtles from the region of Lake Metigoshe, our findings indicate that neonates rely primarily on their ability to remain unfrozen and supercooled. PMID- 9361142 TI - Effect of body size and ration on specific dynamic action in the Antarctic plunderfish, Harpagifer antarcticus Nybelin 1947. AB - The feeding energetics of the Antarctic spiny plunderfish (Harpagifer antarcticus) were examined with respect to the effect of both ration size and animal size. Fish of different sizes were fed single meals at one of two ration levels (2.5% wet body mass and satiation) to determine the maximum aerobic scope that could be elicited by the specific dynamic action. The excretion rates of ammonia, urea, and fluorescamine-positive substances were also monitored. Neither fish size nor ration had any effect on the factorial aerobic scope of feeding, which suggests that cellular metabolic processes associated with feeding were satiated by relatively small meals. The factorial scope in ammonia excretion was affected by both ration and fish size, indicating that respiration and excretion respond to a meal independently. The duration of the specific dynamic action response (240-390 h) increased with fish size but not ration, whereas both the time to reach the peak oxygen consumption and the duration of the ammonia response increased with ration but not fish size. The percentage of the ingested energy that was expended following feeding (the specific dynamic action coefficient) was high at low rations (approximately 56%) but lower (roughly 10%) at satiation rations. This is because the absolute energetic cost of processing a meal was largely independent of meal size. The change in O:N ratios after feeding was very ration-dependent; at low rations, O:N ratios increased, whereas at satiation rations, the O:N ratios decreased. PMID- 9361143 TI - Milk consumption and growth in a marsupial arboreal folivore, the common ringtail possum, Pseudocheirus peregrinus. AB - This study examines the milk consumption and growth energetics of the smallest arboreal folivore in Australia, Pseudocheirus peregrinus. Mass increase was sigmoidal, and young ceased sucking milk between 27 and 30 wk (mean = 29.3 +/- 1 wk). This length of lactation was 129% of that predicted allometrically from data for other marsupials. The mean Gompertz constant (0.01) calculated for seven young suggests that P. peregrinus has a slow rate of growth compared with other marsupial species. Milk intake was measured with isotopic turnover techniques. The estimated total milk energy yield (11.9 MJ kg-1) for a ringtail possum suckling two young was similar to that of the only other marsupial herbivore for which data are available (Macropus eugenii). However, peak milk energy output (154.4 kJ kg-0.75 d-1) was lower than that in other herbivores. The body mass accrued from milk consumption by young ringtail possums at various stages of lactation was similar to that of other marsupials, suggesting that the slow rate of growth in this species is a result of a limited rate of supply of milk energy from the mother and not an inefficient conversion of milk energy in the young. PMID- 9361144 TI - Conservation of mass-specific metabolic rate among high- and low-elevation populations of the acridid grasshopper Xanthippus corallipes. AB - High-elevation populations of many grasshopper species produce small adults in response to shortened growing seasons and cooler ambient temperatures. Mass specific metabolic rate tends to increase with elevation, and several authors have argued that this is an adaptation to accelerate development. In the present study, the relationship of thermoregulation and metabolism was investigated in adults of the acridid grasshopper Xanthippus corallipes from six populations along an elevation gradient. Thermoregulation was measured in the field, and several lines of evidence suggested that afternoon body temperatures were actively maintained within each population. Populations were found to maintain stable afternoon body temperatures that correlate negatively with elevation. Elevation had a strong negative effect on adult mass. Mass-specific metabolic rates at 35 degrees and 45 degrees C correlated positively with elevation. However, population differences in mass explained most of the variation in mass specific metabolic rates, and when mass was used as a covariate, the effect of elevation disappeared. Mass-specific metabolic rates at afternoon field body temperatures were estimated and found not to differ among populations. Thus, differences in thermoregulation offset the effect of mass on mass-specific metabolic rate across populations, such that X. corallipes adults exhibited a common mass-specific metabolic rate in the wild, independent of large population differences in mass and ambient temperatures. PMID- 9361145 TI - Ammonia and urea in the maternal-fetal trophic relationship of the viviparous blenny (eelpout) Zoarces viviparus. AB - A high correlation was observed between the concentration of urea in the maternal plasma and the concentration of urea in the ovarian fluid during post-yolk sac growth of the embryos in the ovary of the viviparous blenny (eelpout) Zoarces viviparus. A high correlation was observed between maternal plasma and ovarian fluid ammonia as well. Ammonia but not urea was excreted to the external medium by the mother fish during pregnancy. Intraovarian loading with either urea or ammonia resulted in a steady decrease from initial high concentrations in the ovarian fluid and a concomitant increase in the maternal plasma levels of both nitrogenous compounds. Injected ammonia was eliminated much faster from the ovarian fluid than urea. No significant effect of any ammonia could be observed on urea excretion rates by embryos in vitro. Patterns of accumulation for urea and ammonia in the external medium were investigated by exposure of embryos in vitro to concentrations of urea and ammonia similar to those normally found in the ovarian fluid. No significant changes could be observed in the external urea or ammonia levels during the experiment. The results indicate that during post yolk sac development of embryos in vivo, net catabolism of nitrogen-containing organics and formation of urea may be reduced by high ambient concentrations of urea in the ovarian fluid. PMID- 9361146 TI - On the utility of uniformity in the definition of basal rate of metabolism. PMID- 9361147 TI - Abolition of breathing rhythmicity in lambs by CO2 unloading in the first hours of life. AB - The mechanisms responsible for the maintenance of regular breathing after initiation of breathing at birth are still poorly understood. This study was designed to test the hypothesis that removing the chemical CO2 drive would abolish breathing rhythmicity in lambs in the first hours of life. A technique of graded CO2 removal through a veno-venous extracorporeal circuit was used in five unanesthetized lambs aged from 4 to 12 hours. In all lambs, CO2 unloading invariably resulted in sustained central apnea, after a decrease in Paco, of 6.9 +/- 5.7 Torr. We were unable to find a significant relationship between the decrease in PaCO2 and PaO2 (range 35-275 Torr) at onset of apnea. During apnea, the passage from behavioral quiet sleep to arousal or to active sleep was marked by transient and weak breathing movements. We conclude that the CO2 drive, but not the behavioral states, is a major factor for maintaining breathing rhythmicity in lambs in the first hours of life. PMID- 9361148 TI - Effects of uni- and bilateral phrenicotomy on active and passive respiratory mechanics in rats. AB - Eighteen spontaneously breathing anesthetized rats were selected to belong to three groups: control (C), unilateral (U), and bilateral phrenicotomy (B). Eight days after surgery, the passive and active mechanical properties of the respiratory system, the shape of the occlusion pressure wave, the decay of inspiratory muscle activity during expiration and control of breathing were analysed. Passive and active elastances increased significantly from C to U and from U to B. Passive and active time constants decreased either in uni- or bilateral phrenicotomies. Passive and active resistances remained unaltered. The intensity of respiratory drive increased from C to U and B. In conclusion, uni- and bilateral phrenicotomies increase the elastic load of the respiratory system, because of both its passive and active components, which raised the respiratory neuromuscular drive of the remaining muscles. Consequently, minute ventilation remained unchanged. The higher frequency was allowed for, by a shorter time constant of the respiratory system and by a faster decay of post-inspiratory muscle activity. PMID- 9361149 TI - Generation and detection of lung stress waves from the chest surface. AB - In anesthetized pigs, we generated stress' waves by imposing a distortion on the intercostal muscle between the 5th and 6th ribs. Stress waves were detected by two accelerometers, 5-7 cm apart, oriented in either the ventral-dorsal or cranial-caudal direction. Cross-spectral analysis was used to calculate transit time. Waves of velocities similar to those of lung shear waves were detected at transpulmonary pressures (Ptp) above 15 cmH2O in the nonedematous lung and above 25 cmH2O Ptp in the edematous lung. Waves were detected in the frequency range 9 40 Hz. Stress wave velocity increased from 287 +/- 24 (SD) cm/sec at 18 cmH2O Ptp to 342 +/- 41 cm/sec at 26 cmH2O Ptp, consistent with shear waves propagating in the lung having a shear modulus of 0.9 Ptp and lung density of 0.20 g/cm3. Stress wave velocities at 25 cmH2O Ptp decreased with the increases in lung density induced by alveolar edema, consistent with elasticity theory. An elasticity analysis showed the existence of lung-rib cage interfacial waves with properties similar to the measured stress waves. PMID- 9361150 TI - Effect of induced hypocapnic hypopnea on upper airway patency in humans during NREM sleep. AB - We wished to determine the effect of reduced ventilatory drive (hypopnea) on upper airway patency in humans during non-rapid-eye-movement (NREM) sleep. We studied nine subjects (58 trials) spanning the spectrum of susceptibility to upper airway collapse including normals, snorers and patients with mild sleep apnea. Hypocapnic hypopnea was induced by abrupt cessation of brief (1 min) nasal mechanical hyperventilation. Surface inspiratory EMG (EMGinsp) was used as an index of drive. Upper airway resistance and supraglottic pressure-flow plots were used as indexes of upper airway patency. Termination of nasal mechanical ventilation resulted in reduced VE to 4904 of pre-mechanical ventilation eupneic control. Upper airway resistance at a fixed flow did not change significantly in inspiration or expiration. Likewise, pressure-flow plots showed no increase in upper airway resistance except in one subject. However, maximum flow (Vmax) decreased during hypopnea in four subjects who demonstrated inspiratory flow limitation (IFL) during eupneic control. In contrast, no IFL was noted in subjects who showed no evidence of IFL during eupnea. We concluded: (1) Reduced ventilatory drive does not compromise upper airway patency in normal subjects during NREM sleep; (2) the reduction in Vmax during hypopnea in subjects with IFL during eupneic control, suggests that reduced drive is associated with increased upper airway compliance in these subjects; and (3) upper airway susceptibility to narrowing/closure is an important determinant of the response to induced hypopnea during NREM sleep. PMID- 9361151 TI - Ventilation inhomogeneities and mixed venous blood N2 in multibreath N2 washout. AB - The single path model of airway gas transport, with and without a distributed blood source term, was used to simulate multiple-breath N2 washout by breathing pure O2 in two lung models: a single-region lung model (SRLM) which produces series inhomogeneity, and a seven-region lung model (7RLM) incorporating both series and parallel inhomogeneities. Normalized phase III slopes (Sn) from N2 expirograms were computed for each breath and compared with published human experimental data obtained under similar conditions. The 7RLM predicts well the trend of experimental Sn N2 changes and is superior to the SRLM in the first part (the unsteady state), implying that this part of the curve is mostly due to convective mixing of the seven parallel flow streams. In the quasi-steady state, the 7RLM is not obviously superior to the SRLM. Functional residual capacity and pulmonary perfusion are shown to strongly affect the number of breaths required to reach the quasi-steady state. The anatomical dimensions that appear to be critical in SRLM are not as important in the 7RLM. PMID- 9361152 TI - The cytoskeleton and the extracellular matrix in sensitized canine tracheal smooth muscle. AB - To investigate the mechanisms responsible for the increased shortening capacity (delta Lmax) of airway smooth muscle in ragweed pollen sensitized dogs, the alterations of biophysical and biochemical properties of cytoskeleton and extracellular collagen in tracheal smooth muscle (TSM) were studied. Smooth muscle passive elastic properties were not significantly altered by removal of cytoskeleton with guanidine HCI plus 2-mercaptoethnol; collagenase digestion reduced smooth muscle force development, but did not affect its delta Lmax and passive elastic properties in both sensitized and control dogs. There were no significant differences in the amount of cytoskeletal intermediate filament proteins, desmin and vimentin between sensitized and control TSM. The content of total collagen, collagen type I, and collagen cross-linking in sensitized TSM were significantly greater than in control. Collagen fibres in sensitized TSM was more resistant to collagenase attack. We conclude that increased delta Lmax in sensitized canine TSM is not the result of alterations in passive cytoskeletal and extracellular collagen structures. PMID- 9361153 TI - The mechanism of action of methotrexate. AB - Because of methotrexate's well-documented efficacy in the treatment of rheumatoid arthritis, it is important that we understand the mechanism of action of this drug. There are two biochemical mechanisms by which methotrexate may modulate inflammation: (1) promotion of adenosine release and (2) inhibition of transmethylation reactions. Evidence is reviewed that favors the notion that the endogenous anti-inflammatory autocoid adenosine mediates the anti-inflammatory effects of methotrexate. This insight should aid in the design of new agents for the treatment of rheumatoid arthritis and other inflammatory diseases. PMID- 9361154 TI - Pharmacology and pharmacokinetics of methotrexate in rheumatic disease. Practical issues in treatment and design. AB - Methotrexate (MTX) is among the most effective drugs for treatment of rheumatoid arthritis and has been proven valuable in the treatment of multiple other disorders of immune regulation. MTX has been administered at a wide range of doses and dose intervals, in conjunction with multiple other drugs, and in patients with a broad range of concomitant disorders. To design a safe and effective MTX treatment plan for an individual patient, the provider must have knowledge of the pharmacology and drug interactions of this effective but potentially dangerous medication. The first section of the article reviews MTX structure, pharmacology pharmacokinetics, and mechanisms of action in rheumatic disease. The second section examines factors that can be used to increase MTX efficacy and decrease toxicity. PMID- 9361155 TI - Methotrexate use in rheumatoid arthritis. AB - To overstate the importance of methotrexate in the contemporary management of rheumatoid arthritis would be difficult. It has achieved this distinction because of its efficacy and tolerability. This article reviews the data on the efficacy and toxicity of methotrexate, discusses caveats for clinical use, examines the use of methotrexate in combination therapy, and speculates on the future use of methotrexate in rheumatoid arthritis. PMID- 9361157 TI - Methotrexate in the treatment of juvenile rheumatoid arthritis and other pediatric rheumatoid and nonrheumatic disorders. AB - The goal of treatment for juvenile rheumatoid arthritis (JRA) and other pediatric rheumatic disorders is to minimize joint destruction, pain, and deformity and to maximize all aspects of growth and development. Oral and injectable methotrexate are now often given early in the treatment of JRA, childhood dermatomyositis, difficult-to-control arthritis in the pediatric spondyloarthropathies, SLE, sarcoidosis, several of the vasculopathies, and idiopathic iritis. Weekly low dose MTX has become a mainstay of long-term improved control of these disorders, and is associated with strikingly few documented long-term side effects. Dosages, pharmacology, side effects, efficacy, and treatment strategies are discussed. Although formal studies are lacking, MTX for the pediatric rheumatic disorders seems to be associated with less frequent physician visits, lower total costs, improved function, and fewer late reconstructive surgeries. PMID- 9361156 TI - Methotrexate use in psoriasis and psoriatic arthritis. AB - Methotrexate is an extremely effective drug in the treatment of psoriasis and psoriatic arthritis. In addition, it possesses a very high benefit-to-toxicity ratio compared with other therapies and immunosuppressive agents used in these disorders. Fortunately, most adverse events related to methotrexate are mild, but serious and life-threatening reactions, particularly liver toxicity, may occur. Careful monitoring is essential to prevent most undesirable side effects. PMID- 9361158 TI - Methotrexate use in systemic vasculitis. AB - Although GS and CYC have been important agents in improving the outcome and survival of patients with systemic vasculitis, they carry their own risk of drug induced morbidity and mortality. It has also become apparent that these medications are not the final answer in disease management because some forms of vasculitis have the potential to relapse or be treatment resistant. For these reasons, the pursuit of effective, less toxic therapeutic alternatives is critical. Initial results from the use of MTX in systemic vasculitis have been encouraging. Although drug-related toxicity and disease relapse have still been found to occur, MTX appears to be a valuable addition in the treatment of vasculitis. Further studies will be necessary to determine the optimal way that this agent may be used to safely and effectively manage vasculitic disease. PMID- 9361159 TI - Methotrexate use in miscellaneous inflammatory diseases. AB - Methotrexate has proven to be a safe, effective, long-term therapy for rheumatoid arthritis. Its property as a corticosteroid-sparing drug in rheumatoid arthritis has been recognized and its potential has been explored in other inflammatory and autoimmune diseases. This article describes and analyzes the use of methotrexate for a wide variety of diseases, some of which are not the usual province of rheumatologists, to provide some guidance concerning its role for treatment. Methotrexate therapy seems promising for systemic lupus erythematosus, inflammatory myopathy, inflammatory eye disease, inflammatory bowel disease, and some manifestations of sarcoidosis. Its role in other diseases is not as well defined. PMID- 9361160 TI - Methotrexate hepatotoxicity. AB - Hepatoxicity is a major adverse reaction that can occur during methotrexate treatment of the rheumatic diseases. The pathologic lesions are nonspecific and the pathogenesis is poorly understood. Early studies in psoriasis clearly established a relationship between hepatic injury and several risk factors, particularly alcohol use. Methotrexate hepatoxicity occurs less frequently in rheumatoid arthritis than previously reported in psoriasis patients. Consequently, the American College of Rheumatology guidelines for methotrexate monitoring do not recommend baseline and surveillance liver biopsies in low-risk patients. These guidelines seem to be useful and cost-effective. PMID- 9361161 TI - Methotrexate pulmonary toxicity. AB - Drug-induced pulmonary disease is a well-recognized complication of MTX treatment of rheumatic diseases. Physicians involved in the management of patients receiving MTX should be aware of this potentially life-threatening complication. The prompt evaluation of new pulmonary symptoms in patients receiving MTX is important in the early recognition of this drug-induced complication. The characteristic symptoms are shortness of breath, nonproductive cough, fatigue, and fever. If an MTX-induced pulmonary reaction is suspected and abnormalities are noted on lung examination, chest radiography should be performed. In the presence of an abnormal chest radiograph, MTX should be discontinued, supportive measures instituted, and the diagnosis of the patient's pulmonary complaints investigated by specifically looking for features of the underlying rheumatic process, infection, and other medical conditions. Patients with severe pulmonary compromise should be hospitalized and given supplemental oxygen and high-dose corticosteroids. Most patients recover from their illness. No risk factors have been identified that consistently identify patients at the greatest risk for MTX induced pulmonary toxicity. All patients receiving MTX should be educated concerning this potentially life-threatening drug toxicity and instructed to contact their physician immediately if significant pulmonary symptoms develop. PMID- 9361163 TI - Does methotrexate increase the risk of infection or malignancy? AB - Most patients do not exhibit overt signs of immunosuppression. Studies cited in this article support a modest increase in the rate of bacterial respiratory and skin infections. Opportunistic infections occur rarely, however, and may be life threatening. The case for MTX carcinogenicity is less clear. The risk for malignancy other than lymphoproliferative disorders does not seem to be elevated, although multiple sporadic malignancies have been reported in treated patients. MTX is a superb agent for the therapy of a large group of immune-mediated diseases. Although an increased risk for infection and possible malignancy exists, the risk is small compared with the potential clinical benefit. PMID- 9361162 TI - The remarkable spectrum of methotrexate toxicities. AB - This article outlines a general scheme for categorizing medication-related adverse events. This is followed by a review of the less well-recognized adverse events attributed to low-dose methotrexate therapy. Known and suspected risk factors are described and causative mechanisms are suggested. Ultimately, this article aims at increasing the readers awareness of uncommon or underreported methotrexate-associated adverse events so that prescribing and monitoring practices can be tailored to enhance the safe use of this valuable antirheumatic agent. PMID- 9361164 TI - The use of folates concomitantly with low-dose pulse methotrexate. AB - Toxicities related to low-dose weekly methotrexate are largely due to its antifolate properties. Preexisting folate deficiency is associated with methotrexate toxicity in some patients. At the onset of methotrexate therapy and throughout therapy, the physician should be vigilant regarding one or more nutrient deficiencies. A multivitamin and, where appropriate, specific daily folic acid supplements should be employed. The only regimen known presently (through controlled trials) to treat side effects is the low-dose folinic acid (leucovorin) protocol outlined herein. Folic acid may be helpful to treat mild gastrointestinal symptoms. Folinic acid supplementation should be considered prophylactically in those requiring methotrexate who are at increased risk of hepatic disease. Other possible factors besides methotrexate should always be considered with the onset of new patient complaints or laboratory abnormalities. Claims that folic acid therapy is safer and more convenient than folinic acid seem unwarranted when one reviews the literature carefully. Cost differences between folic acid supplementation and folinic acid supplementation have been exaggerated. PMID- 9361165 TI - Perioperative use of methotrexate in patients with rheumatoid arthritis undergoing orthopedic surgery. AB - Methotrexate (MTX) is commonly prescribed for the treatment of rheumatoid arthritis. Its use seems to be an independent risk factor for infection with common pathogens and opportunistic organisms. Some rheumatologists and orthopedic surgeons hold the opinion that MTX should be temporarily withheld to lessen the likelihood of postoperative infection or poor wound healing. Alternatively, some clinicians believe that MTX should be continued throughout the perioperative period to avoid flares in rheumatoid arthritis disease activity. There are no definitive studies on which to rely in this decision-making process, but the authors believe that withholding MTX for 2 weeks of the perioperative period is a reasonable and prudent approach. PMID- 9361166 TI - Is there a significant increase in bile duct width after cholecystectomy? PMID- 9361167 TI - Omeprazole 10 milligrams once daily, omeprazole 20 milligrams once daily, or ranitidine 150 milligrams twice daily, evaluated as initial therapy for the relief of symptoms of gastro-oesophageal reflux disease in general practice. AB - BACKGROUND: The efficacy of omeprazole, 20 mg once daily, in the treatment of reflux oesophagitis and the therapeutic advantages over the histamine H2 receptor antagonists are well documented. This study assessed 20 mg omeprazole daily (OM20), 10 mg omeprazole daily (OM10), and 150 mg ranitidine (RAN) twice daily for symptom relief in gastro-oesophageal reflux disease (GORD). METHODS: Patients (n = 994) presenting with heartburn to their general practitioner underwent endoscopy to exclude peptic ulcer disease and were randomized into a UK, multicentre, parallel-group, double-blind comparison of the three treatments for 4 weeks. Symptoms were assessed at clinic visits after 2 and 4 weeks. RESULTS: Symptom relief after 4 weeks was achieved by 61% (OM20), 49% (OM10), and 40% (RAN) patients (OM20 versus OM10, P < 0.0167; OM20 versus RAN, P < 0.0001; OM10 versus RAN, P < 0.01). Among the patients (32%) with erosive reflux oesophagitis, symptom relief was achieved in 79% (OM20), 48% (OM10), and 33% (RAN) (OM20 versus OM10, P < 0.0001; OM20 versus RAN, P < 0.0001; OM1O versus RAN, NS). CONCLUSION: Omeprazole, 20 mg, is the most effective initial therapy for relief of GORD symptoms. PMID- 9361168 TI - Heartburn without oesophagitis: efficacy of omeprazole therapy and features determining therapeutic response. AB - BACKGROUND: Data are limited on the value of effective antisecretory therapy in the relief of heartburn in patients without oesophagitis. METHODS: Patients with heartburn, without endoscopic signs of oesophagitis, were randomized to double blind treatment with omeprazole, 20 or 10 mg once daily, or placebo, for 4 weeks (n = 509). Pre-treatment oesophageal acid exposure was assessed using 24-h intra oesophageal pH monitoring. Heartburn was assessed at 2 and 4 weeks. RESULTS: At 4 weeks the proportion of patients with complete absence of heartburn was 46% (95% confidence interval, 39-53%) with 20 mg omeprazole, 31% (25-38%) with 10 mg omeprazole, and 13% (7-20%) with placebo. Satisfaction with therapy was reported by 66%, 57%, and 31% of the patients, respectively. CONCLUSION: Omeprazole, 20 and 10 mg once daily, provides rapid relief of heartburn in patients without endoscopic oesophagitis. PMID- 9361169 TI - Epidermal growth factor in gastric ulcer healing by nocloprost, a stable prostaglandin E2 derivative. AB - BACKGROUND: The gastroprotective and ulcer-healing properties of prostaglandins, especially in gastric ulcers induced by non-steroidal anti-inflammatory drugs, are well established. Ulcer healing is an active process of filling the mucosal defect with migrating and proliferating epithelial cells combined with angiogenesis in granulation tissue at the ulcer bed. Growth factors, especially epidermal growth factor (EGF) and transforming growth factor alpha (TGF alpha) are crucial in the regulation of the reconstruction of damaged mucosal structures. METHODS: In this double-blind, randomized, prospective study 40 patients with gastric ulcer were treated with nocloprost, a stable prostaglandin E2 derivative, or with ranitidine. All subjects underwent endoscopy before and after 4 and 8 weeks of anti-ulcer therapy. During endoscopy mucosal biopsies were performed for determination of EGF content in gastric mucosa at the ulcer margin and in the intact mucosa. Additionally, EGF output in saliva and its plasma concentrations were determined in all subjects before and during the treatment. RESULTS: The gastric ulcer healing rate after 4 weeks was significantly higher in patients treated with nocloprost than in those treated with ranitidine (63% versus 39%, respectively). At initial examination the EGF content in the gastric mucosa obtained from the ulcer edge was significantly higher than that in the intact mucosa. There was a significant increase in the EGF content in both the ulcer margin and the intact mucosa in subjects treated with nocloprost but not in patients under treatment with ranitidine. Similarly, patients treated with nocloprost had significantly higher EGF output in saliva and higher EGF concentration in plasma throughout the anti-ulcer therapy. CONCLUSION: Nocloprost is superior to ranitidine in the treatment of chronic gastric ulcers, and these effects could be due, at least in part, to higher expression and mucosal content of EGF in the ulcer area. PMID- 9361170 TI - Recombinant human transforming growth factor beta 3 accelerates gastric ulcer healing in rats. AB - BACKGROUND: Gastric ulcer healing is mediated by various endogenous growth factors. In this experimental study effect of locally and systemically applied recombinant human transforming growth factor beta 3 (rhTGF-beta 3) on gastric ulcer healing was investigated in the rat. METHODS AND RESULTS: Gastric ulcers were induced with a cryoprobe, and ulcer healing was evaluated 7 days after local infiltration (0.5 micrograms, 1.0 microgram, 2.5 micrograms, and 50 micrograms) or systemic (intravenous) application of TGF-beta 3 (500 micrograms/kg body weight). Compared with controls, a dose-dependent stimulation of ulcer healing (as evidenced by a reduction in ulcer size) was observed 7 days after local infiltration of TGF-beta 3 (1.0 microgram, 2.5 micrograms, and 50 micrograms). Corresponding increases in the levels of proliferating cell nuclear antigen (PCNA) and intracellular TGF-beta 3 expression and a downregulation of the TGF beta type-II receptor expression were also observed in the granulation tissue of the ulcer margins. Systemic application of TGF-beta 3 produced effects similar to those observed after local treatment with 50 micrograms of the compound. CONCLUSION: Local and systemic TGF-beta 3 treatment accelerates gastric ulcer healing in rats. PMID- 9361171 TI - Lack of effect of omeprazole in oral acenocoumarol anticoagulant therapy. AB - BACKGROUND: Omeprazole is eliminated almost completely by hepatic metabolism within the cytochrome P-450 system and might inhibit the oxidative metabolism of other drugs. This is particularly relevant for compounds with a narrow therapeutic range, such as acenocoumarol. In this study we evaluated the effect of omeprazole use in patients receiving continuous acenocoumarol therapy. METHODS: One thousand and fifty-seven patients receiving long-term oral acenocoumarol combined with omeprazole were selected retrospectively. In 118 of these patients omeprazole was considered the only factor of possible influence on anticoagulant therapy. The control group consisted of 299 age- and sex-matched patients taking acenocoumarol without interfering medication. Dose adjustment of acenocoumarol on starting omeprazole therapy was indicated by clinically relevant changes in coagulation time. RESULTS: No adaptation of the anticoagulant dose was necessary in 74 of 118 omeprazole patients (62.7%), compared with 169 of 299 controls (56.5%). A higher dose was necessary in 30 of 118 omeprazole patients (25.4%), compared with 84 of 299 controls (28.0%). In 14 of 118 omeprazole patients (11.9%) a lowering of the anticoagulant dose was required, compared with 46 of 299 controls (15.4%). CONCLUSIONS: We found no evidence of any interaction between omeprazole and acenocoumarol. It seems likely that omeprazole can be administered safely to patients treated with acenocoumarol. PMID- 9361172 TI - The influence of circulatory and gut luminal challenges on bidirectional intestinal barrier permeability in rats. AB - BACKGROUND: The endothelial and epithelial barriers are important for maintenance of intestinal barrier function. The present study evaluated the response of these barriers after various challenges. METHODS: Mucosal endothelial and epithelial barrier integrity was evaluated by the leakage of human serum albumin, labeled with different isotopes, from the circulation to the interstitium and the intestinal lumen, or from the intestinal lumen to the interstitium and the circulation, in rats with endothelial or epithelial challenge. RESULTS: Epithelial barrier dysfunction and alterations in epithelial microvillous ultrastructure showed a pattern dependent on the dose of the intraluminal detergents, whereas only higher doses induced an increase in endothelial barrier permeability. Intravenous challenge with CHAPS or Triton caused a dose-dependent increase in both endothelial and epithelial barrier permeability. The development of endothelial barrier dysfunction was related to a decrease in blood pH values. CONCLUSIONS: The results indicate that capillary endothelial barrier integrity may play an important role in maintaining intestinal barrier function and that endothelial injury may initiate or at least be involved in the development of intestinal barrier failure. PMID- 9361173 TI - Clinical course during the 1st year after diagnosis in ulcerative colitis and Crohn's disease. Results of a large, prospective population-based study in southeastern Norway, 1990-93. AB - BACKGROUND: The clinical course and prognosis in ulcerative colitis (UC) and Crohn's disease (CD) have been described in many studies, mostly retrospective. Such studies are hampered by problems such as inclusion over a long time period, proper definitions, incomplete case records, and outdated methods of diagnosis. In a prospective study we identified 846 patients with inflammatory bowel disease (IBD) over a 4-year period from 1990 to 1993. Uniform diagnostic and therapeutic strategies were used as a basis for later assessment of the short-term clinical course in different subgroups of UC and CD and analysis of potential risk factors for relapse or surgery. METHODS: At the time of follow-up, a mean of 16.2 months after diagnosis, 496 UC patients and 232 CD patients, altogether 98%, were available for evaluation. A colonoscopy was performed in 88% (410 of 465) of the UC patients attending a clinical examination and in 76% (164 of 216) of the CD patients. RESULTS: Eleven patients with UC and five patients with CD died during follow-up, four of complications related to IBD. The cumulative 1-year relapse rate in the remaining patients was 50% for UC and 47% for CD. Of the patients with relapses 11 % of the UC patients and 10% of the CD patients had a chronic relapsing course without any difference with regard to the various disease categories in UC or CD. An increased risk of relapse was found in patients less than 50 years old only in UC. In UC a higher risk for surgery was found in patients with extensive colitis compared with left-sided colitis (P = 0.011), and CD patients with small-bowel involvement had a higher risk of surgery than patients with disease confined to the colon (P = 0.021). There was no excess risk of relapse or surgery in smokers as compared with non-smokers or former smokers, nor did the risk of relapse vary with the level of cigarette consumption in either UC or CD patients. CONCLUSION: The high relapse rate of around 50% for both UC and CD calls for a review of the existing treatment. Further follow-up will be necessary to improve our ability to make clinical decisions relating to medical and surgical treatment options. PMID- 9361174 TI - Inflammatory bowel disease: a study of the association between anxiety and depression, physical morbidity, and nutritional status. AB - BACKGROUND: The etiology of inflammatory bowel disease is unclear, and the role played by anxiety and depression is highly controversial. Anxiety and depression in patients with inflammatory bowel disease could be secondary to disabling symptoms, but the interaction between physical morbidity and psychologic illness in these subjects has not been sufficiently investigated. Patients with inflammatory bowel disease are nevertheless frequently undernourished, but there are no studies on the association between anxiety and depression and malnutrition. This study was designed to characterize anxiety and depression in subjects affected by inflammatory bowel disease and to establish the influence of physical morbidity and/or nutritional status on psychologic disorders. METHODS: Seventy-nine consecutive patients, 43 with Crohn's disease (CD) and 36 with ulcerative colitis (UC), were enrolled in the study. An index of the disease activity and physical morbidity was obtained by the simplified Crohn's Disease Activity Index and Truelove-Witts criteria and using the Clinical Rating Scale. Thirty-six healthy volunteers were studied as controls. All the subjects were given the State and Trait Anxiety Inventory (STAI) test and the Zung self-rating Depression Scale. RESULTS: The percentage of subjects with state anxiety was significantly higher in the CD (P < 0.001) and UC (P < 0.001) groups than in control subjects. There was no significant difference in trait anxiety among groups. The percentage of subjects with depression was significantly higher in the CD (P < 0.05) and UC (P < 0.05) groups than in control subjects. State anxiety and depression were significantly associated with physical morbidity and correlated with malnutrition in CD and UC patients. CONCLUSION: Anxiety and depression in patients with inflammatory bowel disease could be reactive to the disabling symptoms and to malnutrition. As measured with the STAI, personality trait of anxiety does not seem to play an important role in inflammatory bowel disease. PMID- 9361175 TI - TAP gene transporter polymorphism in inflammatory bowel diseases. AB - BACKGROUND: Many studies suggest the implication of genetic factors in inflammatory bowel diseases. Despite some associations with HLA genes, the lack of definite data may be due to ethnic variations, clinical heterogeneity, or the involvement of additional susceptibility genes beside or within the major histocompatibility complex (MHC), such as TAP genes. The aim of this study was to analyze in patients with ulcerative colitis (UC) or Crohn's disease (CD) the polymorphism of TAP genes that encode the proteins necessary for the transfer of antigenic peptides through the endoplasmic reticulum membrane. METHODS: One hundred and one UC and 148 CD patients were compared with 173 unrelated healthy controls. Dimorphisms within the TAP1 and TAP2 alleles were analyzed by sequence specific oligonucleotide typing. RESULTS: No difference was found between patient groups and controls. However, when CD patients were classified on the basis of their responsiveness to steroid therapy, a significant decrease of TAP2 AA (*0101/*0101) genotype was found in CD patients who did not respond to steroid therapy (22.9% versus 43.7% in steroid responder group; Pc < 0.05; odds ratio = 2.6; 95% confidence limits (CL) = 1.2-5.9). These data appear independent of the distribution of HLA DRB1*01 or DRB1*03 alleles despite a significant linkage disequilibrium between these alleles and TAP2A. CONCLUSIONS: This result suggests, despite the absence of arguments favoring a genetic susceptibility to CD, that the TAP2 gene or other genes located on chromosome 6 may be involved in the genetic heterogeneity of CD. PMID- 9361176 TI - Intestinal interleukin-8 concentration and gene expression in inflammatory bowel disease. AB - BACKGROUND: Interleukin-8 (IL-8) is an important cytokine for recruitment and activation of polymorphonuclear neutrophils (PMNs), cells that are abundant in the intestinal lesions of ulcerative colitis (UC) and Crohn's disease (CD). The present investigation was conducted to evaluate intestinal IL-8 concentration and IL-8 gene expression in parallel in inflammatory bowel disease (IBD) patients and a non-inflammatory control group. METHODS: The intestinal concentration of IL-8 was measured with a sandwich enzyme-linked immunosorbent assay (ELISA) technique (detection limit, 17.4 pg/mg protein), and relative quantitation of IL-8 mRNA transcript levels was done with a reverse transcription polymerase chain reaction (RT-PCR)-based method. Biopsy specimens from 66 humans who underwent colonoscopy- 28 with UC, 18 with CD and colonic involvement, and 20 non-inflammatory disease specific controls who subsequently were found to fulfill the diagnostic criteria for irritable bowel syndrome (IBS)--were included. None had received glucocorticoids within 3 months. RESULTS: Using a one-tailed variance analysis, a significant concordance between increasing IL-8 protein concentrations and disease activity was found both in UC and CD (P < 0.001), and only trace amounts were detected in IBS biopsy specimens. No differences were found between the two groups of UC and CD patients (P > 0.05), and no differences were found between quiescent IBD and IBS (P > 0.05). However, the PCR method showed IL-8 mRNA in 8 of 18 CD patients (44.4%; 95% confidence limits, 21.5-69.2%) and 7 of 28 UC patients (25.9%; 95% confidence limits, 11.1-46.3%), as compared with 0 of 20 IBS (P < 0.005). Increased IL-8 mRNA levels were found only in active CD, which was not the case in UC. No correlation was found between intestinal IL-8 ELISA and IL 8-mRNA levels (r = 0.24, P > 0.05). CONCLUSIONS: The observed correlation between disease activity and expression of the IL-8 gene in active CD colitis but not in UC and the increased IL-8 protein concentrations in affected intestinal segments of IBD as compared with the non-inflamed IBS indicate a possible transient IL-8 gene expression or altered mRNA stability in UC and CD, as is well known for other cytokines, such as IL-2. If so, it may form the basis of new therapeutic regimens for IBD like IL-10. PMID- 9361177 TI - K-RAS-2 gene mutations as predictors of metachronous colorectal adenomas. AB - BACKGROUND: Mutations of K-RAS-2 gene and tumour suppressor genes have been found in both colorectal adenomas and carcinomas. The aim of this study was to investigate the prognostic value of K-RAS-2 gene mutations found in initial colorectal adenomas for predicting the risk of metachronous adenomas. METHODS: Genomic DNA was extracted from formalin-fixed and paraffin-embedded adenomas larger than 5 mm in diameter removed at the initial total colonoscopy between 1980 and 1982. All patients underwent colonoscopic follow-up for at least 10 years. The sequence of exon 1 of the K-RAS-2 oncogene was amplified with the polymerase chain reaction technique and screened for mutation by single-strand conformation polymorphism analysis. All suspected mutations were confirmed by direct DNA sequencing. The predictive value of K-RAS-2 gene mutations for the risk of metachronous adenomas was assessed by chi-square testing and logistic regression analysis. RESULTS: Of 54 patients 39 (72%) were male and 15 (28%) female. At the time the initial adenoma was removed, 31 (57%) patients were younger than 60, whereas 23 (43%) were 60 years or older. Point mutations of the K-RAS-2 oncogene were found in the index adenomas of 15 (27.7%) patients. Mutations were found more frequently in large (> or = 20 mm) adenomas and in adenomas with severe dysplasia (P = 0.0011 and P = 0.0310, respectively). There were no significant associations between K-RAS-2 mutations and anatomic location, histologic type, or number of synchronous initial lesions. Mutations were found predominantly at codon 12 with transversions from GGT to GTT (57%), from GGT to GAT (36%), and from GGT to TTT (one patient). The single mutation found at codon 13 showed a transversion from GGC to GAC. There were significant associations between size (> or = 20 mm) and K-RAS-2 mutation of the initial adenomas and the size (> 5 mm) of metachronous adenomas (P = 0.0259 and P = 0.0265, respectively). However, multivariate analysis showed that K-RAS-2 mutations did not provide a significant additional contribution to the prognostic value of the size of the initial adenoma (odds ratio, 7.62; 95% confidence interval (CI), 1.68-34.48) and the amount of villous structure (odds ratio, 0.22; 95% CI, 0.05-0.90) it contained. CONCLUSIONS: Patients with large (> or = 20 mm) adenomas and adenomas with K-RAS-2 mutations found at the initial examination have a significantly higher risk of developing large (> 5 mm) metachronous adenomas during surveillance. Multivariate analysis of initial adenoma characteristics showed that the risk of metachronous colorectal adenomas can be adequately estimated by the size and the histologic type of the largest initial adenoma and that K-RAS-2 mutations are of secondary importance only. Further studies based on a larger series will have to identify the adenoma characteristics that will help to improve follow-up strategies. PMID- 9361178 TI - Survival and risk of cholangiocarcinoma in patients with primary sclerosing cholangitis. A population-based study. AB - BACKGROUND: Endoscopic retrograde cholangiopancreatography was introduced in the early 1970s, making a more reliable diagnosis of primary sclerosing cholangitis (PSC) possible. Since then decreased survival and increased risk of cholangiocarcinoma have been reported. However, no population-based studies have quantified these outcomes. METHODS: A population-based cohort of 125 patients with a verified PSC diagnosis was followed up through linkage to the Swedish Death Registry and the Swedish Cancer Registry for occurrence of death and cholangiocarcinoma. RESULTS: The diagnosis of PSC was associated with a substantially decreased survival, with an overall 10-year survival of 68.8%. Patients with a diagnosis of inflammatory bowel disease (IBD) had a somewhat better prognosis, 71.8%, compared with 60% for patients without. Fourteen subsequent cholangiocarcinomas yielded a cumulative risk of 11.2% 10 years after diagnosis. Sex, duration of IBD, and colectomy influenced neither the survival nor the cholangiocarcinoma risk. CONCLUSION: Patients with PSC have a substantially decreased survival, which is most pronounced among patients without IBD. PMID- 9361179 TI - Chronic non-A, non-B, non-C hepatitis: is hepatitis G/GBV-C involved? AB - BACKGROUND: Hepatitis G virus/GBV-C is a recently discovered virus, and its relevance in chronic hepatitis is still debated. METHODS: We have previously described 127 long-term-studied and well-characterized patients with chronic non A, non-B hepatitis (NANBH). Ninety-one (71.7%) were positive for hepatitis C virus antibodies (anti-HCV) in a first-generation anti-HCV enzyme-linked immunosorbent assay (ELISA). We now reanalyzed the same group of patients and added a third-generation anti-HCV ELISA and recombinant immunoblot assay and, in negative patients, also polymerase chain reactions for hepatitis C virus RNA, hepatitis GBV-C RNA, and hepatitis B virus DNA. Additional tests for autoimmune hepatitis types 2 and 3 were also included. RESULTS: Anti-HCV were detected in 114 of the 123 evaluable patients (92.7%). Of the remaining nine anti-HCV negative patients one had misdiagnosed primary biliary cirrhosis, and two had autoimmune hepatitis type 3. None of the anti-HCV-negative patients were hepatitis GBV-C RNA-, HCV RNA-, or HBV DNA-positive. Thus, 114 of 120 NANBH patients (95.0%) had chronic hepatitis C. None of the remaining six patients had received blood transfusions or was a drug addict, and two of them were successfully treated with steroids. CONCLUSIONS: Hepatitis G/GBV-C as a single cause of chronic non-A, non-B hepatitis is uncommon, and in all patients with parenteral risk factors hepatitis C was detected. PMID- 9361180 TI - The significance of colocalization of plasminogen activator inhibitor-1 and vitronectin in hepatic fibrosis. AB - BACKGROUND: We examined the relationships among vitronectin (VN), plasminogen activator inhibitor-1 (PAI-1), and transforming growth factor beta 1 (TGF-beta 1) in liver diseases to evaluate the presence of plasmin cascade in human hepatic fibrosis. METHODS: Blood and liver tissues were obtained from 57 patients with liver disease. Plasma VN, PAI-1 antigen, and PAI-1 activity levels were evaluated. Biopsied liver specimens were observed by light and electron microscopy after immunohistochemical staining. Morphometric analysis was performed on these specimens. RESULTS: Plasma VN and PAI-1 activity levels decreased significantly with the progression of hepatic fibrosis and were particularly marked in the liver cirrhosis group. Plasma PAI-1 antigen level increased significantly. The immunolocalization of the active form of TGF-beta became more intense with the progression of hepatic fibrosis, whereas that of the dual-stained positive areas of PAI-1 and VN (PAI-1.VN) decreased. There was a positive correlation between TGF-beta and PAI-1, whereas there was a negative correlation between TGF-beta and PAI-1.VN. Immunoelectron microscopy showed the localization of PAI-1-VN in the extracellular space around the sinusoidal cells or surface of aggregating platelets, TGF-beta mainly in Ito cells, and VN in hepatocytes near the focal necrotic area or fibrous septa. CONCLUSIONS: These findings suggest that VN and PAI-1 are related to the active form of TGF-beta and that it is possible that the plasmin cascade is present in the human liver. PMID- 9361181 TI - Prevalence and incidence of gallstones in liver cirrhosis. AB - BACKGROUND: Our aim was to assess the prevalence and incidence of gallstone disease in patients with liver cirrhosis and to identify risk factors for cholecystolithiasis. METHODS: We studied a cohort of 313 patients with liver cirrhosis confirmed by histology and/or laparoscopy and 357 patients free of liver disease, who had been referred for ultrasonographic examination of the upper abdomen. Hepatobiliary ultrasonography was performed when liver cirrhosis was diagnosed and every 6 months thereafter. Risk factors for cholelithiasis (age, gender, diet, pregnancy, diabetes, family history of cholelithiasis, etiology of cirrhosis, decompensated disease) were assessed. RESULTS: The overall prevalence of gallstones in cirrhotic patients was 23.3%. In controls, the overall prevalence of cholecystolithiasis was 16.8%. After a median follow-up period of 65 months, 30 patients developed gallstones. The calculated annual incidence was 3.4%. CONCLUSIONS: Given that the prevalence of gallstone disease is higher in cirrhotics than in noncirrhotic patients, cirrhosis of the liver may be considered a risk factor for cholecystolithiasis. PMID- 9361182 TI - Kohlmeier-Degos's disease with primary intestinal manifestation. AB - Disseminated intestinal and cutaneous thromboangiitis (synonyms: Kohlmeier Degos's syndrome, malignant atrophic papulosis, progressive arterial mesenterial vascular occlusive disease) is a rare, systemic vascular disease that is mainly manifested in the skin, gastrointestinal tract, and nervous system. The disease first appears as a necrotizing papulous dermatosis; as it generalizes, infarcted necroses develop in internal organs. These ischemic complications are the reason for the usually fatal outcome of the disease. A case report of a primary intestinal manifestation of this disease illustrates the clinical course, diagnosis, histopathologic findings, and differential diagnosis, with consideration of the current literature. Deposits of acid mucopolysaccharides and humoral immune mechanisms appear to play a role in the etiology and pathogenesis of this usually fatal vascular disease. PMID- 9361183 TI - Increase in pH and prevention of gastropathy induced by nonsteroidal anti inflammatory drugs. PMID- 9361184 TI - 1 alpha,25-dihydroxyvitamin D3 receptor as a mediator of transrepression of retinoid signaling. AB - The receptors for retinoic acid (RA) and for 1 alpha,25-dihydroxyvitamin D3 (VD), RAR, RXR, and VDR are ligand-inducible members of the nuclear receptor superfamily. These receptors mediate their regulatory effects by binding as dimeric complexes to response elements located in regulatory regions of hormone target genes. Sequence scanning of the tumor necrosis factor-alpha type 1 receptor (TNF alpha RI) gene identified a 3' enhancer region composed of two directly repeated hexameric core motifs spaced by 2 nucleotides (DR2). On this novel DR2-type sequence, but not on a DR5-type RA response element, VD was shown to act through its receptor, the vitamin D receptor (VDR), as a repressor of retinoid signalling. The repression appears to be mediated by competitive protein protein interactions between VDR, RAR, RXR, and possibly their cofactors. This VDR-mediated transrepression of retinoid signaling suggests a novel mechanism for the complex regulatory interaction between retinoids and VD. PMID- 9361185 TI - Retinoblastoma-related protein pRb2/p130 and its binding to the B-myb promoter increase during human neuroblastoma differentiation. AB - Neuroblastoma cells can undergo neural differentiation upon treatment with a variety of chemical inducers and growth factors. During this process, many cell cycle-related genes are downregulated while differentiation-specific genes are triggered. The retinoblastoma family proteins, pRb, p107, and pRb2/p130, are involved in transcriptional repression of proliferation genes, mainly through their interaction with the E2F transcription factors. We report that pRb2/p130 expression levels increased during differentiation of neuroblastoma cell line LAN 5. On the other hand, both pRb and p107 decreased and underwent progressive dephosphorylation at late differentiation times. The expression of B-myb and c myb, two targets of the retinoblastoma family proteins, were downregulated in association with the increase of pRb2/p130, which was detected as the major component of the complex with E2F on the E2F site of the B-myb promoter in differentiated cells. Interestingly, E2F4, a preferential partner of p107 and pRb2/p130, was upregulated and underwent changes in cellular localization during differentiation. In conclusion, our data suggest a major role of pRb2/p130 in the regulation of B-myb promoter during neural differentiation despite the importance of cofactors in modulating the function of the retinoblastoma family proteins. PMID- 9361187 TI - Binding-induced activation of overexpressed p185HER2 is essential in triggering neuronal differentiation of PC12 cells. AB - To determine whether p185HER2 overexpression per se triggers p185HER2 cellular signaling or whether an extracellular signal is required, we transfected PC12 cells with the human erbB-2 proto-oncogene, and established a cell line that overexpresses p185HER2. PC12-HER2 cells, maintained in suspension culture or plated on a collagen layer, showed the same morphology and growth rate as PC12 and PC12 mock-transfected control cells. When treated with monoclonal antibody (MAb) MGr6 or other anti-p185HER2 MAbs, PC12-HER2 cells specifically underwent neuronal differentiation comparable to that induced by nerve growth factor (NGF), and the differentiation-inducing effect of the MAb was dramatically enhanced by the addition of a second anti-mouse IgG. MAb-induced cell differentiation correlated with p185HER2 phosphorylation, recruitment of Shc and Grb-2 transducer molecules into complexes, and MAPK phosphorylation. These data indicate the requirement for a specific binding-induced activation of the overexpressed p185HER2 receptor in inducing PC12 cell differentiation. PC12-HER2 cells represent a suitable system for selection of p185HER2-activating ligands (peptides, phage-displayed peptides or proteins) or specific inhibitors of its tyrosine kinase activity. PMID- 9361186 TI - Identification of a cysteine protease responsible for degradation of sperm histones during male pronucleus remodeling in sea urchins. AB - We have identified a 60-kDa cysteine protease that is associated with chromatin in sea urchin zygotes. This enzyme was found to be present as a proenzyme in unfertilized eggs and was activated shortly after fertilization. At a pH of 7.8 8.0, found after fertilization, the enzyme degraded the five sperm-specific histones (SpH), while the native cleavage-stage (CS) histone variants remained unaffected. Based on its requirements for reducing agents, its inhibition by sulfhydryl blocking compounds and its sensitivity to the cysteine-type protease inhibitors (2S,3S)-trans-epoxysuccinyl-L-leucyl-amido-3-methylbutane-ethyl-es ter (E-64 d), cystatin and leupeptin, this protease can be defined as a cysteine protease. Consistently, this protease was not affected by serine-type protease inhibitors phenylmethylsulfonyl fluoride (PMSF) and pepstatin. The substrate selectivity and pH modulation of the protease activity strongly suggest its role in the removal of sperm-specific histones, which determines sperm chromatin remodeling after fertilization. This suggestion was further substantiated by the inhibition of sperm histones degradation in vivo by E-64 d. Based on these three lines of evidence, we postulate that this cysteine protease is responsible for the degradation of sperm-specific histones which occurs during male pronucleus formation. PMID- 9361188 TI - Cyclic strain stimulates isoform-specific PKC activation and translocation in cultured human keratinocytes. AB - Previous studies have demonstrated that cyclic strain induces keratinocyte proliferative and morphological changes. Since protein kinase C (PKC) is known to play an important role in the regulation of keratinocyte growth and differentiation, the objective of this study was to determine the role of the PKC signaling pathway as a mediator of strain modulation of the keratinocyte phenotype. In particular, we tested the following specific hypotheses: (1) cyclic strain stimulates PKC activity and translocation, (2) cyclic strain activates PKC in an isoform-specific manner, and (3) PKC mediates the strain activated proliferative and morphological response in cultured human keratinocytes. To test these hypotheses, keratinocytes were subjected to vacuum-generated cyclic strain (10% average strain), followed by measurement of PKC activity, PKC isoform distribution by Western blot analysis and confocal microscopy, and examination of the effect of PKC inhibitors (calphostin C and staurosporine) on strain induced proliferative and morphological changes. We observed stimulation of PKC activity (62.3 +/- 5.1% increase) coupled with translocation of PKC from the cytosolic to the membrane fraction in keratinocytes subjected to acute cyclic strain. Cyclic strain also caused translocation of PKC alpha and delta, but not zeta isoforms, from the cytosolic to the membrane fraction as demonstrated by both Western blot analysis and confocal microscopy. PKC beta was not detected in these cells. PKC inhibitors, calphostin C (10 nM), and staurosporine (5 nM), inhibited strain induced PKC activation and keratinocyte proliferation, but did not block the effects of strain on cellular morphology or alignment. We conclude that these data support our hypothesis that cyclic strain stimulates PKC activity and translocation in an isoform-specific manner in cultured human keratinocytes. Moreover, our studies with PKC inhibitors support the hypothesis that strain induced changes in the keratinocyte phenotype may be selectively modulated by PKC. PMID- 9361189 TI - Differential effects of ascorbate depletion and alpha,alpha'-dipyridyl treatment on the stability, but not on the secretion, of type IV collagen in differentiated F9 cells. AB - Ascorbic acid stimulates secretion of type I collagen because of its role in 4 hydroxyproline synthesis, but there is some controversy as to whether secretion of type IV collagen is similarly affected. This question was examined in differentiated F9 cells, which produce only type IV collagen, by labeling proteins with [14C]proline and measuring collagen synthesis and secretion. Hydroxylation of proline residues in collagen was inhibited to a greater extent in cells treated with the iron chelator alpha,alpha'-dipyridyl (97.7%) than in cells incubated without ascorbate (63.1%), but both conditions completely inhibited the rate of collagen secretion after 2-4 h, respectively. Neither treatment affected laminin secretion. Collagen synthesis was not stimulated by ascorbate even after treatment for 2 days. On SDS polyacrylamide gels, collagen produced by alpha,alpha'-dipyridyl-treated cells consisted mainly of a single band that migrated faster than either fully (+ ascorbate) or partially (- ascorbate) hydroxylated alpha 1(IV) or alpha 2(IV) chains. It did not contain interchain disulfide bonds or asn-linked glycosyl groups, and was completely digested by pepsin at 15 degrees C. These results suggested that it was a degraded product lacking the 7 S domain and that it could not form a triple helical structure. In contrast, the partially hydroxylated molecule contained interchain disulfide bonds and it was cleaved by pepsin to collagenous fragments similar in size to those obtained from the fully hydroxylated molecule, but at a faster rate. Kinetic experiments and monensin treatment suggested that completely unhydroxylated type IV collagen was degraded intracellularly in the endoplasmic reticulum or cis Golgi. These studies indicate that partial hydroxylation of type IV collagen confers sufficient helical structure to allow interchain disulfide bond formation and resistance to pepsin and intracellular degradation, but not sufficient for optimal secretion. PMID- 9361190 TI - cAMP-dependent protein kinase inhibits the mitogenic action of vascular endothelial growth factor and fibroblast growth factor in capillary endothelial cells by blocking Raf activation. AB - Proliferation of endothelial cells is regulated by angiogenic and antiangiogenic factors whose actions are mediated by complex interactions of multiple signaling pathways. Both vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) stimulate cell proliferation and activate the mitogen activated protein kinase (MAPK) cascade in bovine brain capillary endothelial (BBE) cells. We have extended these findings to show that both mitogens activate MAPK via stimulation of Raf-3. Activation of Raf/MAPK is inhibited by increasing intracellular cAMP levels pharmacologically or via stimulation of endogenously expressed beta-adrenergic receptors. Both VEGF- and bFGF-induced Raf-1 activity are blocked in the presence of forskolin or 8-bromo-cAMP by 80%. The actions of increased cAMP appear to be mediated by cAMP-dependent protein kinase (PKA), since treatment with H-89, a the specific inhibitor of PKA, reversed the inhibitory effect of elevated cAMP levels on mitogen-induced cell proliferation and Raf/MAPK activation. Moreover, elevations in cAMP/PKA activity inhibit mitogen-induced cell proliferation. These findings demonstrate, in cultured endothelial cells, that the cAMP/PKA signaling pathway is potentially an important physiological inhibitor of mitogen activation of the MAPK cascade and cell proliferation. PMID- 9361191 TI - Inducible expression of a mutant form of MEK1 in Swiss 3T3 cells. AB - We conditionally overexpressed a MEK1 mutant that contains triple mutations in the regulatory and kinase domains, and investigated its effects on the MAP kinase cascade in Swiss 3T3 cells. Expression of the mutant produced a 60% blockade in MAP kinase activity. However, only a modest blockade in DNA synthesis was observed, without any reductions in the phosphorylation of two proteins known to be substrates of MAP kinase. Moreover, the overexpression of MEK1(3A) failed to block endogenous MEK1 activation, although MEK1(3A) formed complexes with both c Raf and B-Raf as well as p42/p44 MAPK. These results suggest that there may be multiple biochemical inputs into the MEK/MAPK pathway. PMID- 9361192 TI - Increased expression of c-jun, but not retinoic acid receptor beta, is associated with F9 teratocarcinoma stem cell differentiation induced by polyamine depletion. AB - alpha-Difluoromethylornithine (DFMO), an enzyme-activated irreversible inhibitor of ornithine decarboxylase, and all-trans-retinoic acid (RA) are known to induce F9 teratocarcinoma stem cell differentiation. Both compounds induce the formation of the same cell type, i.e., parietal endoderm-like cells expressing tissue plasminogen activator and collagen type IV alpha-1. The present study shows that DFMO and RA induce terminal differentiation of F9 cells through different pathways. Thus, retinoic acid receptor (RAR) alpha mRNA is weakly expressed during DFMO treatment, but strongly induced during an early phase of RA treatment. RAR beta mRNA is not detectable in DFMO-treated cells, but very strongly induced by RA and maintained at a high level throughout the differentiative process. RAR gamma mRNA is relatively strongly expressed in untreated control cells and remains at approximately the same level during DFMO induced differentiation. In RA-treated cells, however, RAR gamma mRNA is rapidly down-regulated and becomes nondetectable during the final course of differentiation. These experiments show that the differentiation of F9 cells into parietal endoderm-like cells does not necessarily involve changes in any of the RAR mRNA subtypes. Even though the steady-state levels of the RAR alpha and RAR gamma transcripts may be sufficient to support the differentiative process, our data clearly show that induction of RAR beta mRNA transcription is neither a prerequisite for F9 cell differentiation, nor an absolute consequence of the elevated c-jun mRNA expression that is consistently observed during the course of parietal endoderm differentiation. PMID- 9361193 TI - Regulation of bone matrix protein expression and induction of differentiation of human osteoblasts and human bone marrow stromal cells by bone morphogenetic protein-2. AB - We have examined the effects of BMP-2 on the expression of bone matrix proteins in both human bone marrow stromal cells (HBMSC) and human osteoblasts (HOB) and their proliferation and mineralization. Both HBMSC and HOB express BMP-2/-4 type I and type II receptors. Treatment of these two cell types with BMP-2 for 4 weeks in the presence of beta-glycerophosphate and ascorbic acid results in mineralization of their matrix. BMP-2 increases the mRNA level and activities of alkaline phosphatase and elevates the mRNA levels and protein synthesis of osteopontin, bone sialoprotein, osteocalcin, and alpha 1(I) collagen in both cell types. Whereas the mRNA level of decorin is increased, the mRNA concentration of biglycan is not altered by BMP-2. No effect on osteonectin is observed. The effect of BMP-2 on bone matrix protein expression is dose dependent from 25 to 100 ng/ml and is evident after 1-7 days treatment. In the presence of BMP-2, proliferation of HBMSC and HOB is decreased under either serum-free condition or in the presence of serum. Thus, BMP-2 has profound effects on the proliferation, expression of most of the bone matrix proteins and the mineralization of both relatively immature human bone marrow stromal preosteoblasts and mature human osteoblasts. PMID- 9361194 TI - Characterization of interior cleavage of retinoblastoma protein in apoptosis. AB - Previously we reported that at the onset of apoptotic execution, retinoblastoma protein (RB) was cleaved in its interior region, resulting in production of two major fragments, p48 and p68, and that the RB interior cleavage was mediated by a caspase-like activity. Here, we further characterized the RB interior cleavage process in human leukemia cells treated with the anticancer agent etoposide. We found that the RB interior cleavage activity was much more sensitive to two specific tetrapeptide caspase inhibitors, YVAD-CMK and DEVD-FMK, than the poly(ADP-ribose) polymerase cleavage activity, suggesting that two distinct caspases are involved in these processes. Several Asp residues are located in amino acids 341-421 of RB protein, and cleavage of any one of these sites by a caspase would generate a p48, which contains the amino terminus, and a p68 fragment, which contains the A/B pocket and the carboxyl terminus. This hypothesis was supported by the fact that the p48 and p68 fragments had selective binding affinity to different RB antibodies and that the p48 was found only in the low-salt-extracted cytoplasmic fraction, while the p68 was only in the nuclear fraction, of the apoptotic cells. However, the nuclear binding partner of the p68 RB fragment is not the transcription factor E2F-1 since a specific E2F-1 antibody coimmunoprecipitated only the unphosphorylated form of RB, but not the p68 fragment. Lastly, we confirmed that RB also underwent dephosphorylation and carboxyl terminal cleavage during apoptosis, as we and others reported previously. PMID- 9361195 TI - Inhibition of cytoskeletal reorganization stimulates actin and tubulin syntheses during injury-induced cell migration in the corneal endothelium. AB - A single layer of squamous epithelial cells termed the "endothelium" resides upon its natural basement membrane (Descemet's membrane) along the posterior surface of the vertebrate cornea. A well-defined circular freeze injury to the center of the tissue exposes the underlying basement membrane and results in the directed migration of surrounding cells into the wound center. This cellular translocation is characterized by the reorganization of the actin and tubulin cytoskeletons. During migration, circumferential microfilament bundles are replaced by prominent stress fibers while microtubules, observed as delicate lattices in non-injured cells, become organized into distinct web-like patterns. To determine whether this cytoskeletal reorganization requires actin or tubulin synthesis, injured rabbit endothelia were organ cultured for various times and metabolically labeled with 35S-methionine/cystine (250 microCi/ml) for the final 6 h of each experiment. Analysis of actin and tubulin immunoprecipitates indicated no significant increases in 35S incorporation occurred during the course of wound repair when compared to isotope incorporation in noninjured tissues. However, when cytoskeletal reorganization was hampered, either by pre-treating tissues with 7 microM phalloidin to stabilize their circumferential microfilament bundles, or culturing in the presence of 10(-8)M colchicine to dissociate microtubules, 35S incorporation increased significantly into both actin and tubulin immunoprecipitates at 48 h post-injury. Furthermore, in both cases, exposure to actinomycin D substantially suppressed isotope incorporation. These results indicate that cytoskeletal rearrangement of microfilaments and microtubules during wound repair, in corneal endothelial cells migrating along their natural basement membrane, utilizes existing actin and tubulin subunits for filament reorganization. Disrupting this disassembly/reassembly process prevents cytoskeletal restructuring and leads to the subsequent initiation of actin and tubulin syntheses, as a result of increased transcriptional activity. PMID- 9361196 TI - Hydrolysis characteristics of bovine milk fat and monoacid triglycerides mediated by pregastric lipase from goats and kids. AB - Commercial extracts from oro-pharyngeal tissues of goats and kids have been used as the source of pregastric lipase and have been processed to yield partially purified samples of the primary pregastric lipase. The activity of these lipases against tributyrylglycerol has been determined over a range of pH and temperatures. Optimum pH conditions for pregastric lipase ranged from pH 5.6 to 6.5 for goats and from pH 5.5 to 6.2 for kids, respectively; the optimum temperature ranged from 43 to 60 degrees C. Optima for kid lipase extended slightly below pH 5.5 and higher than 60 degrees C; which were the limits of the test conditions. The enzymes were also used as catalysts for the hydrolysis of monoacid triglycerides (C4:0 to C12:0) at 40 degrees C and pH 6.5; activity was maximum against tributyrylglycerol (C4:0). Values for the Michaelis-Menten constant, increased as carbon chain length of the carboxylic moiety on the triglycerides increased, but values were identical for pregastric lipases of both goats and kids. Anhydrous milk fat was hydrolyzed by the commercial extracts of pregastric lipases of goats and kids, and the resulting profiles for free fatty acids were very similar to one another and to the corresponding profile for a commercial sample of Parmesan cheese. There appear to be no significant differences in activity between the enzyme preparations from goats and kids. PMID- 9361197 TI - Hydrolysis of caprine beta-casein by plasmin. AB - The proteolytic activity of plasmin on soluble caprine beta-casein (CN) was studied in 50 mM Tris.HCI buffer, pH 8.0, at 37 degrees C. Electrophoretic studies showed that hydrolysis of this protein results in an electrophoretic pattern that is similar to the pattern obtained from plasmin hydrolysis of bovine beta-CN (gamma-CN and complementary N-terminal fragments), suggesting that plasmin probably attacks the same regions that are susceptible to cleavage in bovine beta-CN. As determined by SDS-PAGE, the gamma-like components of caprine milk consisted of two fragments with relative molecular mass of 9200 and two with relative molecular mass of 21,400 that could differ in the level of phosphorylation. Apparently, the high molecular mass components are homologous to bovine beta-CN (f 29-209) (gamma 1-CN), and the low molecular mass components are homologous to bovine beta-CN (f 106-209) and beta-CN (f 108-209) (gamma 2- and gamma 3-CN). Complementary N-terminal fragments had values for molecular masses in the range 13,600 to 8500 and urea-PAGE patterns that were more complex than those obtained in bovine casein because of the different phosphorylation levels in caprine beta-CN. These fragments were also present in the hydrolysate of whole caprine casein that had been treated with plasmin. PMID- 9361198 TI - Differences in the hydrolysis of lactose and other substrates by beta-D galactosidase from Kluyveromyces lactis. AB - The hydrolysis of o-nitrophenyl galactopyranoside and lactose by beta-D galactosidase from Kluyveromyces lactis was enhanced by the addition of Mg2+ and Mn2+, but the rates of activation by each metal on both substrates were not the same. The Co2+, Zn2+, and Ni2+ activated the o-nitrophenyl galactopyranoside hydrolyzing activity of the enzyme, but these same metals inhibited the lactose hydrolyzing activity. The addition of Mg2+ and EDTA to the assay buffer increased the hydrolysis of o-nitrophenyl galactopyranoside and lactose at different rates. The responses of o-nitrophenyl galactopyranoside and lactose to the enzyme activity were different as a function of pH. The hydrolyzing activity toward both substrates also was influenced by the concentration of the phosphate in the assay buffer. However, the profile of the enzyme activity toward each substrate was different as a function of concentration. Because the assay of beta-galactosidase using o-nitrophenyl galactopyranoside is fast and convenient, the estimation of lactose-hydrolyzing activity of the enzyme has frequently been made based on the assay of o-nitrophenyl galactopyranoside hydrolysis. As shown in this study, a slight change in the conditions of the assay system and the enzyme application may cause changes in the ability of the enzyme to hydrolyze both lactose and o nitrophenyl galactopyranoside. The change in o-nitrophenyl galactopyranoside hydrolyzing activity is not always consistent with that of the lactose hydrolyzing activity under the given condition, which may cause an inaccurate estimation of the enzyme activity in the enzyme preparation as well as in actual applications of the enzyme. PMID- 9361199 TI - Characterization by ionization mass spectrometry of lactosyl beta-lactoglobulin conjugates formed during heat treatment of milk and whey and identification of one lactose-binding site. AB - The extent of the early stage of the Maillard-type reaction that impaired functional properties of whey proteins was evaluated by electrospray ionization mass spectrometry. Under conditions of mild heat treatment (63 degrees C for 20 s) applied to milk before whey separation at room temperature 23 degrees C), a modification of the relative molecular mass of beta-lactoglobulin (beta-LG) was observed that differed from that of the native form by 324. This specific modification of beta-LG occurred in acidified whey as well as in sweet whey and increased with the extent of the heat treatment. Incubation of purified beta-LG dissolved in milk ultrafiltration permeate or in lactose solution at 50 to 80 degrees C demonstrated the presence of a lactosyl residue that was covalently bound to beta-LG; beta-casein, used as a control, showed no mass modification. Studies of kinetics showed that a maximum of 35% of the beta-LG was lactosyl-beta LG conjugate after heat treatment at 70 degrees C for 1 h. This study provides the first direct evidence of specific lactosylation of beta-LG during the initial stage of the Maillard reaction. One of the first lactose-binding sites was identified as a Lys47 by protease mapping and analysis by means of on-line liquid chromatography combined with mass spectrometry. In addition, collision-activated dissociation performed on the lactosylated peptide beta-LG (f 46-51) showed the rearrangement reactions occurring during the fragmentation process by electrospray. A mechanism is proposed. PMID- 9361200 TI - Automated control and monitoring of thermal processing using high temperature, short time pasteurization. AB - High temperature, short time pasteurization was used to evaluate a computer-based system for controlling the pasteurization process, acquiring data, and monitoring records. Software was used for the control of hot water temperature, flow rate through the centrifugal timing pump, and diversion of under-processed product. Three types of control strategies were conducted: single loop, cascade, and multivariable. The single loop control strategy showed the most rapid responses to temperature changes, but the temperature response curve was slowest to return to its set point. The cascade control strategy showed slower recoveries to temperature changes, but the temperature response curve was smoother. The multivariable control strategy responded slightly faster than the cascade control strategy, and the temperature response curve was slightly smoother than the cascade control strategy. The multivariable control strategy was able to control the flow diversion valve by the use of a lethality controller. The data acquisition system, used to monitor the data obtained from the high temperature, short-time pasteurization system, was within +/- 0.1 degree C of the temperature recorded by the safety thermal limit recorder. Reliability was determined by examining the changes in the position of the flow diversion valve to identify process deviations and by comparing the changes to the event marker on circular charts. The data acquisition system was an effective alternative for monitoring the completeness of data. PMID- 9361201 TI - Effect of high hydrostatic pressure on Escherichia coli and Pseudomonas fluorescens strains in ovine milk. AB - Ovine milk that had been standardized to 6% fat was inoculated with Escherichia coli 405 CECT and Pseudomonas fluorescens 378 CECT at a rate of 10(6) and 10(7) cfu/ml, respectively, and treated with high hydrostatic pressure. Treatments consisted of combinations of pressure (300, 400, 450, and 500 MPa), temperature (2, 10, 25, and 50 degrees C), and time (5, 10, and 15 min). Inactivation (> 6 log cfu/ml) of both strains was observed at 50 degrees C for all pressures and treatment times. A similar level of inactivation occurred at > or = 450 MPa and 25 degrees C for E. coli and at > or = 400 MPa and 10 degrees C for P. fluorescens. Destruction was lowest at 10 degrees C for E. coli and at 25 degrees C for P. fluorescens. The test strain of E. coli was more baroresistance than was the P. fluorescens strain. PMID- 9361202 TI - Resistance of yeast flora of labaneh to potassium sorbate and sodium benzoate. AB - Ten yeast cultures belonging to eight species representing the yeast flora of labaneh were tested for their resistance to potassium sorbate and sodium benzoate. Changes in counts were monitored after 7, 14, and 21 d at 5 degrees C in yeast-free labaneh containing different concentrations of potassium sorbate or sodium benzoate. More than 400 mg/kg of sodium benzoate were needed to limit the counts of Saccharomyces cerevisiae (biovariants 1, 2, and 7) Cryptococcus curvatus, Pichia farinosa, Candida blankii, Debaryomyces hansenii, and Trichosporon brassicae to < or = 10(5) cfu/g after 14 d at 5 degrees C; 150 and 300 mg/kg were needed for Geotrichum candidum and Trichosporon cutaneum, respectively. When potassium sorbate was used, > 400 mg/kg were needed for P. farinosa and D. hansenii; 350 mg/kg were needed for S. cerevisiae biovar 1, Cr. curvatus, and C. blankii; 250 and 200 mg/kg were needed for S. cerevisiae biovariants 2 and 7, respectively; and < 100 mg/kg were needed for T. brassicae, T. cutaneum, and G. candidum. Less than 150 and < 250 mg/kg of potassium sorbate and sodium benzoate, respectively, were needed to limit yeast counts to < 10(5) cfu/g for 7 d at 5 degrees C in two commercial labaneh samples that had initial yeast counts of 4.8 x 10(2) and 9.0 x 10(2) cfu/g; 200 and > 400 mg/kg were required when the storage was extended to 14 d. In commercial labaneh with 9.6 x 10(3) cfu/g, > 300 and > 400 mg/kg of potassium sorbate and sodium benzoate, respectively, were needed to limit the yeast count to < or = 10(5) cfu/g after 7 and 14 d at 5 degrees C. PMID- 9361203 TI - Properties of porcine and yogurt lactobacilli in relation to lactose intolerance. AB - Lactobacilli that had been isolated from the stomach of piglets were tested for properties relevant to the production of fermented milk products for consumption by lactose-intolerant humans. The strains were characterized for beta galactosidase activity, the ability to reduce the lactose concentration of milk, viability, and pH of the fermented milk over a 30-d period. Strains that had favorable attributes were studied further, and the optimal pH for beta galactosidase activity, ability to grow in the presence of bile salts, and ability to deconjugate bile salts were determined. Commercial yogurts were also examined to determine whether products varied in characteristics that might affect tolerance of milk products by lactose-intolerant subjects. The Lactobacillus sp. isolated from pigs had lower beta-galactosidase activity than did Lactobacillus delbrueckii ssp. bulgaricus strains ATCC 11842 and NCDO 1489 and strains of lactobacilli isolated from yogurt. The beta-galactosidase activity of all strains decreased rapidly once the fermented milk was stored at 4 degrees C. Strain JB10, originating in the stomach contents of the piglets, had properties that were useful for the manufacture of fermented milk products for lactose-intolerant humans. Milk fermented by this strain had a lactose concentration of about 4.0% and contained 6.6 x 10(6) cfu/ml after storage at 4 degrees C for 20 d. Strain JB10 produced a beta-galactosidase that was active at pH 5.5 (35% of the activity at pH 7.0) and was not inhibited by the presence of bile acids in the culture medium. Beta-Galactosidase activity and lactose concentration varied among yogurts. PMID- 9361204 TI - Antiproliferative effects of yogurt fractions obtained by membrane dialysis on cultured mammalian intestinal cells. AB - The consumption of yogurt has been associated with a reduced incidence of colon cancer in population groups. Bioactive peptides produced during bacterial fermentation may alter the risk of colon cancer via modification of cell proliferation in the colon. Using our previously described cell culture model system, we have isolated a yogurt fraction that decreases cell proliferation. Yogurt was fractionated using 10,000- and 500-Da membrane dialysis. When the yogurt fraction was incubated with IEC-6 or Caco-2 cells, cell division was decreased compared with control treatments, as determined by thymidine incorporation. Cell division was not inhibited in response to a similarly produced milk fraction or in response to solutions of lactic acid. The determination of cell kinetics by flow cytometry revealed a decrease in the number of cells in the initial growth phase in response to the yogurt fraction for the IEC-6 cells, but not the Caco-2 cells. Alpha-Lactalbumin inhibited cell division of both cell lines, but beta-casein did not. PMID- 9361205 TI - Immunomodulatory effect of bovine lactoferrin pepsin hydrolysate on murine splenocytes and Peyer's patch cells. AB - The effects were examined of a pepsin hydrolysate of bovine lactoferrin on the proliferation of murine splenocytes. The hydrolysate enhanced [3H]thymidine uptake by splenocytes, but undigested bovine lactoferrin exerted an inhibitory effect. The hydrolysate had the ability to inhibit the blastogenesis that was induced by mitogens such as concanavalin A, phytohemagglutinin, and lipopolysaccharide; inhibition was similar to that with undigested lactoferrin. These results suggested that the hydrolysate contained both immunostimulatory and immunoinhibitory peptides. The stimulatory effect of the hydrolysate in the absence of mitogens was then explored in more detail using nonadherent splenocytes. The proliferative response of splenocytes to the hydrolysate was much greater in the fraction that was enriched with B cells than in the fraction that was enriched with T cells. The hydrolysate did not affect thymocyte proliferation. These data indicated that the adherent cells resembling macrophages and found among the splenocytes were not the target cells of the hydrolysate. The stimulatory effect of the hydrolysate was due to the activation of B cells by the hydrolysate and enhanced immunoglobulin production by splenocytes. Because the hydrolysate also enhanced the proliferation and immunoglobulin A production of Peyer's Patch cells, the immunostimulatory effect of the hydrolysate in vivo was examined using mice that had been orally immunized with cholera toxin. The concentrations of immunoglobulin A conjugated against cholera toxin in bile and in the intestinal contents of mice fed liquid diets containing 1% (wt/vol) lactoferrin hydrolysate were greater than those of mice fed control diets. This result suggested that the use of the lactoferrin hydrolysate is beneficial to enhance mucosal immunity. PMID- 9361206 TI - A model to describe growth patterns of the mammary gland during pregnancy and lactation. AB - Extensive proliferation and death of cells in the mammary gland occur during pregnancy and lactation. In this study, a mechanistic model was developed that yielded a single equation to describe the pattern of mammary growth of mammals throughout pregnancy and lactation. The model contains a single pool, which is the cell population of the mammary gland; one influx, representing cell proliferation; and one efflux, representing cell death. The parameters of the equation lend themselves to direct physiological interpretation. The model fitted data on mammary gland DNA adequately and can be related to current knowledge on factors and inhibitors of mammary gland growth. A unique definition of the parameters of the model can be difficult because of the high degree of variation among animals, an improper number of observations, or timing, as indicated by analyses of simulated data. The model can also be applied to the study of the entire lactation curve. The widely applied gamma equation and the equation that was developed in this study were compared using weekly production data from dairy cows. The new model performed well, particularly when a sharp peak in milk production occurred. The model has the advantage of providing, for the first time, a simple biological description of the lactation curve that can be used to discriminate changes in lactational performance that are associated with experimental treatments. PMID- 9361207 TI - Administration of recombinant bovine somatotropin to dairy cows for four consecutive lactations. AB - Effects of long-term administration of recombinant bovine somatotropin (bST) to dairy cows on complete lactational performance [60 (+/- 3) to 284 (+/- 3) d in milk (DIM)] were studied for four consecutive lactations. Beginning on d 60 (+/- 3) postpartum, Holstein cows received biweekly injections (500 mg) of bST (n = 39) or a placebo (control; n = 39) during the first lactation of the study. Cows either continued on the same treatment (n = 26) or were switched to the opposite treatment (n = 29) during the second lactation. Cows that changed treatments were injected for only 16 wk during the second lactation. Six cows per treatment completed four consecutive lactations. Treatment with bST during the first lactation did not have a residual effect on milk yields during the second lactation. Injections of bST during the second lactation increased milk yield 6.5 kg/d from 60 (+/- 3) to 172 DIM. For the four lactations, cows receiving bST yielded 3.7 kg/d (14%) more milk and gained 52 kg (37%) more body weight than did controls. Pretreatment (from 0 to 56 DIM) milk yields in yr 2, 3, and 4 were not affected by previous bST treatment. Milk yield, efficiency of feed utilization, and body weights were enhanced in cows injected with bST for four consecutive lactations. Previous bST treatment did not diminish milk yields in subsequent lactations. PMID- 9361208 TI - The role of insulin in the regulation of milk protein synthesis in dairy cows. AB - We examined the role of insulin in milk protein synthesis using the hyperinsulinemic-euglycemic clamp approach in combination with abomasal infusion of casein. The two experimental periods consisted of abomasal infusion of water or 0.5 kg/d of casein. An insulin clamp was conducted over the last 4 d of each period. During the insulin clamp, circulating insulin was elevated fourfold, and euglycemia was maintained by the infusion of exogenous glucose. Casein infusion increased milk yield so that milk protein yield was 10% greater than baseline values. Use of the insulin clamp combined with casein infusion increased milk protein yield by 230 g/d (28% greater than baseline values). Milk protein composition was not altered, but content was increased from 3.13% during the baseline period to 3.44% by d 4 of the clamp; calcium concentration in milk increased about 10% to 1.2 g/kg. During the clamp, circulating concentrations of essential amino acids were dramatically reduced. The most pronounced effects were noted for branched-chain amino acids (64% reduction from baseline values). The insulin clamp resulted in alterations in circulating insulin-like growth factor (IGF)-I concentrations (increase) as well as IGF-II and IGF-binding protein-2 concentrations (decreases). Overall, results indicated that the ability of the mammary gland to synthesize milk protein does not function at maximum capacity, and there is a previously unrecognized potential to enhance milk protein percentage and yield. PMID- 9361209 TI - Effect of stages of lactation on the concentration of a 90-kilodalton heat shock protein in bovine mammary tissue. AB - From the normal mammary tissue of a Holstein cow in late lactation, a heat shock protein (90 kDa) was purified by ammonium sulfate fractionation and five-step column chromatography. From 70 g of tissue, 9.5 mg of this heat shock protein were obtained; samples had 98% purity and 19% recovery. The molecular mass of the 90-kDa heat shock protein was estimated to be 86 kDa by SDS-PAGE. Analysis of the amino-terminal amino acid sequence suggested that the protein had been purified as a mixture of two isoforms. The contents of the heat shock protein in cytoplasmic fractions of mammary tissues from Holstein heifers and cows at lactation and involution were measured by quantitative immunoblot analysis using rabbit antiserum raised against the purified heat shock proteins. The contents of the heat shock protein were higher in tissues from lactating cows than in those from heifers and involuting cows. The elevated concentrations of cytoplasmic 90 kDa heat shock protein in lactating tissue suggested that this protein is involved in mammary differentiation and lactation. PMID- 9361210 TI - Effects of replacement of native fat in colostrum and milk with coconut oil on fat-soluble vitamins in serum and immune function in calves. AB - Fat-soluble vitamins and their metabolites modulate immune function in a variety of animal species. The objective of the present study was to determine the role of fat-soluble vitamins in colostrum and milk in the development of specific aspects of immune function in the calf during the 1st wk postpartum. During this period, control calves (n = 6) were fed normal colostrum and milk, and calves in the treatment group (n = 6) were fed skimmed colostrum and skimmed milk supplemented with coconut oil. Treated calves did not experience the progressive increase in concentrations of retinol, beta-carotene, alpha-tocopherol, 1,25 dihydroxyvitamin D, or retinoic acids in serum that was observed in control calves. Acquisition of passive immunity, which is indicated by concentrations of immunoglobulin G1 in serum, was unaffected by treatment. Composition and functional capacities of populations of blood mononuclear leukocytes that were collected from birth to 7 d postpartum were also unaffected by treatment. Major changes in the function and composition of mononuclear leukocyte populations from all calves occurred during the experimental period and were unrelated to the concentrations of fat-soluble vitamins in serum. Populations of blood mononuclear leukocytes from calves were functionally hyporesponsive and compositionally different from populations of blood mononuclear leukocytes from adult nongravid cows. These differences likely reflected the immaturity of the immune system of the neonatal calf and may contribute to the increased susceptibility of the calf to infectious disease. PMID- 9361211 TI - Effects of infection by caprine arthritis-encephalitis virus on milk production of goats. AB - The effects of caprine arthritis-encephalitis virus on lactational performance of goats were examined. The results of an ELISA for antibodies against caprine arthritis-encephalitis virus were compared with milk production records. Mean production of milk, protein, fat, and lactose and somatic cell counts were compared for seropositive and seronegative goats of similar ages. The results from 1799 lactating goats from 66 herds suggested that milk production was similar for 1-yr-old goats that tested seropositive and those that tested seronegative. For 900 of those goats for which data permitted comparison, milk fat and protein were also similar. A comparison of 331 goats showed that lactose contents did not differ between 1- and 2-yr-old goats, but somatic cell counts were higher in 2-yr-old seropositive goats. PMID- 9361212 TI - Responses of antibody titers to intramammary immunization with Escherichia coli J5 bacterin. AB - The effect of an immunization schedule on responses of antibody titers was tested following vaccination with an Escherichia coli J5 bacterin. Eighteen cows were equally distributed among three immunization schedules: 1) subcutaneous injection at 14 d prior to the end of lactation, intramammary immunization at 7 d after drying off, and subcutaneous injection at 30 d into the dry period; 2) subcutaneous injections at drying off, at 30 d into the dry period, and within 12 h after calving; and 3) unimmunized controls. The E. coli J5 bacterin consisted of 5 ml of 10(9) boiled cells/ml of 0.9% NaCl plus 0.005% phenol emulsified with 5 ml of Freund's incomplete adjuvant. Subcutaneous injections were administered on the upper part of the rib cage, posterior to the scapula. Intramammary immunizations of 2.5 ml of bacterin were infused via the teat canal into each of the four mammary glands. Intramammary immunization increased rectal temperatures at 12 h after infusion, but subcutaneous injections did not induce febrile responses. Intramammary immunization enhanced immunoglobulin G titers in serum and whey on d 0 of lactation compared with subcutaneous immunizations. Immunoglobulin G titers in serum also were greater at d 30 of the dry period and at d 14 and 21 of lactation for cows that received intramammary immunization than for cows that were vaccinated by subcutaneous injections only. Immunoglobulin M titers in whey and serum on d 21 of lactation were greater for cows that received intramammary immunizations than for cows that were immunized by subcutaneous injections only. PMID- 9361213 TI - Associations between function and composition of blood mononuclear leukocyte populations from Holstein bulls treated with dexamethasone. AB - To characterize further the effects of corticosteriod-induced stress on the immune system of dairy cattle, functional and phenotypic characteristics of populations of blood mononuclear leukocytes from control and treated (0.04 mg dexamethasone/kg per d for 3 consecutive d) Holstein bulls were evaluated concurrently. In vivo administration of dexamethasone caused a > or = 97% reduction in in vitro secretion of interferon-gamma by pokeweed mitogen stimulated mononuclear leukocytes by d 2 after the first treatment. In vitro secretion of immunoglobulin M was reduced by > 50% on d 2 and 3 after the first treatment, but returned to normal concentrations sooner than did interferon-gamma secretion. Concurrent with changes in the secretion of these proteins were changes in the mean fluorescence intensities of major histocompatibility class I and II antigens and the WC1 antigen and in the proportion of B cells, CD3 T cells, gamma delta T cells, and cells in the leukocyte population expressing major histocompatibility class II antigens. Examination of the relationships between protein secretion in vitro and the composition of the blood mononuclear leukocyte population indicated that secretion was associated positively with the proportion of CD3 T cells (primarily the gamma delta T-cell subset) and the expression of major histocompatibility class I and II molecules and associated negatively with the proportion of cells expressing major histocompatibility class II antigens. Overall, these results suggest that corticosteroid-mediated stress in dairy cattle impairs secretion of proteins that are critical to normal cellular and humoral immune responses, an effect that is strongly linked with changes in the composition of the circulating mononuclear leukocyte population. PMID- 9361214 TI - The effects of restraint using self-locking stanchions on dairy cows in relation to behavior, feed intake, physiological parameters, health, and milk yield. AB - Holstein cows (n = 64) ranging from peak to end lactation were restrained in self locking stanchions (i.e., head locks) for approximately 4 h/d for four periods in a modified switchback design. Milk yield, milk fat percentage, somatic cell count, and dry matter intake and dry matter intake were unaffected by restraint. Milk protein percentage was significantly lower for cows that were restrained. Plasma cortisol concentrations and the ratio of neutrophils to mononuclear cells were not significantly different between restrained and unrestrained (control) cows. No difference in the incidence of mastitis or other health concerns was noted. Behaviorally, cows that were locked in the stanchions spent significantly more time lying after release from restraint. For cows that were locked up, eating frequency over 24 h was significantly reduced, but dry matter intake was not affected. Total rumination frequency over 24 h was not significantly different for cows that were restraubed; however, cows that were restrained ruminated less during the day following release. Grooming was considered to be a behavioral need and was significantly increased during all times when cows were not locked up. Grooming was also one of the first behaviors performed following release. Acts of aggression were elevated during all periods following restraint, but oral behaviors, such as tongue playing and chewing on objects, drinking behavior, and resting postures were not affected. The use of self-locking stanchions did not appear to affect substantially the overall well-being of the cow. PMID- 9361215 TI - Modeling ruminal pH fluctuations: interactions between meal frequency and digestion rate. AB - A steady periodic analysis of ruminal carbohydrate digestion was developed to predict the effects of diet and frequency of eating on ruminal pH fluctuation. Tests of the model against previous data showed that pH fluctuations were too large when previously published rates of carbohydrate digestion were used but were improved using rates from an in vitro gas production system, which were lower. With the original digestion rates, the minimum meal frequency to maintain steady-state conditions in the rumen increased from 4 to 12 meals/d as dietary effective neutral detergent fiber (NDF) decreased from 34 to 6% of dry matter (DM); with the revised rates, the minimum frequency was 3 to 6 meals/d, respectively. The minimum effective NDF to maintain a pH value above 6.0 increased from 14 to 23% of DM as meal frequency decreased from steady state to 2 meals/d using the original rates; with the revised rates, the minimum effective NDF was slightly smaller, increasing from 13 to 21% of DM, respectively. Effects of DM intake and body weight on pH fluctuation were minor, and dietary buffers, when used at rates less than 1%, did not reduce fluctuation. Different methods of calculating mean ruminal pH yielded different results for the effect of meal frequency on mean pH. PMID- 9361216 TI - The endogenous polysaccharide utilization rate of mixed ruminal bacteria and the effect of energy starvation on ruminal fermentation rates. AB - When mixed ruminal bacteria were starved in vitro for 24 h, cellular ATP decreased, but there was little change in cell protein. Starved ruminal bacteria derived most of their ATP from cellular polysaccharide. Because polysaccharide declined at a first-order rate of 23%/h, it was possible to estimate the endogenous polysaccharide utilization rate at various stages of starvation by multiplying the amount of utilizable polysaccharide remaining at each time point by 0.23. The bacteria initially had a rate of soluble carbohydrate fermentation that was > 717 micrograms of hexose equivalent/mg of protein per h. Starvation had little impact on the rate of soluble carbohydrate fermentation until 8 to 12 h, and the endogenous polysaccharide utilization rate was < 10 micrograms of hexose/mg of protein per h. The bacteria digested ball-milled cellulose at a rate of 24 micrograms of hexose/mg of protein per h for 8 to 12 h. Even bacteria that had been starved for 24 h fermented cellulose at a rate of 16 micrograms of hexose/mg of protein per h. The rate of methane production was initially 70 nmol of methane/mg of protein per min. Short periods of starvation (< 12 h) had little impact on methane production, but longer times caused an almost complete inhibition of methanogenesis. The rate of amino acid deamination was initially 31 nmol of ammonia/mg of protein per min, and the critical phase of starvation was again 8 to 12 h. Ruminal bacteria that were harvested at 24 h after feeding had 10-fold less polysaccharide than did bacteria that were harvested at 2 h after feeding, but this polysaccharide supported high rates of soluble carbohydrate and cellulose fermentation, deamination, and methane production. PMID- 9361217 TI - Nutritional risk factors in the etiology of left displaced abomasum in dairy cows: a review. AB - The transition period occurring 2 wk prepartum through 2 to 4 wk postpartum is the major risk period in the etiology of left displaced abomasum. The prepartum depression of intake and the slow postpartum increase in intake are risk factors causing lower ruminal fill, reduced forage to concentrate ratio, and increased incidence of other postpartum disorders. Uncomplicated ketosis, retained placenta, metritis, and hypocalcemia at parturition are risk factors for left displaced abomasum. Excessive amounts of concentrate during the prepartum period increase the risk of left displaced abomasum, which may occur from the lower ruminal fill caused by greater prepartum intake depression and reduced forage to concentrate ratio, decreased ruminal motility from lower ruminal fill and higher volatile fatty acid concentration, and decreased abomasal motility and emptying from higher concentrations of volatile fatty acids. Effects of volatile fatty acids on motility may be exacerbated by low ruminal absorption of volatile fatty acids during the transition period. Minimal intake of concentrate during the prepartum period may increase the risk of left displaced abomasum through failure to increase the absorptive capacity of the ruminal papillae and failure of the microbial population of the rumen to adapt prior to the intake of high energy postpartum diets. Increased risk of left displaced abomasum in cows that are hypocalcemic at parturition may be due to decreased ruminal and abomasal motility. PMID- 9361218 TI - Rumen fermentation and nutrient flows for cows fed grass and grass supplemented with molassed beet pulp pellets. AB - An experiment was carried out to determine the effect of a grass diet and a concentrate supplement on rumen fermentation and nutrient flows to the duodenum. Perennial ryegrass was cut and fed indoors to eight rumen- and duodenum cannulated Friesian cows with or without 3 kg/d of molassed beet pulp in a randomized design experiment. The dry matter intake of grass was significantly lower for cows fed the concentrate supplement (13.6 vs. 11.5 kg of dry matter/d), but total dry matter and organic matter (OM) intakes were similar for cows fed both diets. Cows fed the supplement had higher mean concentrations of total volatile fatty acids (108 vs. 89 mmol/L) and a higher percentage of butyrate in total volatile fatty acids (13.5 vs. 11.6 mol/100 mol). There were no differences between the diets in the flow of OM to the duodenum or in the extent of OM digestion in the rumen. Flows of nonammonia N, microbial N, and amino acids to the duodenum tended to be higher for cows fed the supplemented diet than for those fed ryegrass only. The efficiency of microbial protein synthesis also tended to be higher for cows fed the supplemented diet (42 vs. 37.7 g/kg of OM apparently digested in the rumen and 28.2 vs. 26 g/kg of OM truly digested in the rumen). Overall, there were indications that the supplement caused better capture of N in the rumen and increased the efficiency of microbial protein synthesis. PMID- 9361219 TI - Comparison of hull-less barley, barley, or corn for lactating cows: effects on extent of digestion and milk production. AB - Six lactating, cannulated Holstein cows were used in a double 3 x 3 Latin square design to compare the effects of hull-less barley with barley and corn on ruminal fermentation, rate of passage, flow of nutrients to the duodenum, and milk production. Diets consisted of 60% concentrate, 30% barley silage, and 10% alfalfa hay (dry matter basis). Concentrates contained steam-rolled grains: hull less barley, barley, or corn. Dry matter intake was unaffected by grain source, but starch intake tended to be greatest when hull-less barley or corn was fed. The barley diet was more degradable in the rumen than was the hull-less barley or corn diet, and, therefore, flow of microbial organic matter to the duodenum was greatest for cows fed the barley diet. Flow of microbial N to the duodenum was greater (50 g/d) for cows fed the barley diet than for cows fed the other diets, and the flow of ruminally undegradable N was greater (43 and 28 g/d) for cows fed the hull-less barley and corn diets, respectively, than for cows fed the barley diet. As a result, flow of nonammonia N to the duodenum was unaffected by grain source. Total tract apparent digestibility was highest for cows fed the barley and corn diets. Despite its low digestibility, cows fed the hull-less barley diet produced a similar amount of milk as did cows fed the barley and corn diets. Further studies are needed to evaluate the effects of processing hull-less barley on its utilization by dairy cows. PMID- 9361220 TI - Energy and nitrogen balance in lactating cows fed diets containing dry or high moisture corn in either rolled or ground form. AB - The effects of harvesting and processing methods on the value of net energy for lactation of corn grain were investigated. Lactating Holstein cows were used in a replicated Latin square design with a 2 x 2 factorial arrangement of treatments. Treatments were different methods for the storage (dry or high moisture) and processing (rolled or ground) of corn grains. Alfalfa silage was the forage source in the diets. Indirect calorimetry was conducted using a 6-d nutrient balance protocol; respiration measurements were made at 24-h intervals. Dry matter intake did not differ among treatments and averaged 24.2 kg/d. Milk yield was 2.0 kg/d greater for cows fed diets containing high moisture corn than for cows fed diets containing dry corn and was 2.2 kg/d greater for cows fed diets containing ground corn than for cows fed diets containing rolled corn. Apparent digestibilities of nonfiber carbohydrates, crude protein, and dry matter were greater for cows fed diets containing high moisture corn than for cows fed diets containing dry corn. Metabolizable energy and heat production were greater for diets containing high moisture corn than for diets containing dry corn and were greater for diets containing ground corn than for diets containing rolled corn. Net energy for lactation was greater for diets containing high moisture corn than for diets containing dry corn (1.78 vs. 1.64 Mcal/kg of dry matter). PMID- 9361221 TI - Impact of the maturity of corn for use as silage in the diets of dairy cows on intake, digestion, and milk production. AB - Whole-plant corn was harvested at early dent, quarter milkline, two-thirds milkline, and black layer stages to evaluate the effects of maturity on intake, digestion, and milk production when corn was fed as silage in the diet. Twenty multiparous Holstein cows were used in a replicated experiment with a 4 x 4 Latin square design with 28-d periods. Diets containing 50% forage (67% corn silage and 33% alfalfa silage) and 50% concentrate (dry matter basis) were fed as total mixed rations. Moisture contents were 69.9, 67.6, 64.9, and 58.0% for silages from corn harvested at early dent, quarter milkline, two-thirds milkline, and black layer stages, respectively. Intakes of dry matter were similar across the four treatments and ranged from 3.73 to 3.79% of body weight. Milk production was highest (33.4 kg/d) for cows fed silage from corn harvested at the two-thirds milkline stage and lowest (32.4 kg/d) for cows fed silage from corn harvested at the early dent stage. Milk protein production was highest for cows fed silage from corn harvested at the two-thirds milkline stage (1.17 vs. 1.12 to 1.13 kg/d). Apparent total tract digestion of dry matter, organic matter, crude protein, acid detergent fiber, and starch was lowest for cows fed silage from corn harvested at the black layer stage. Although starch intake was similar for cows fed silage from corn harvested at the two-thirds milkline stage and for cows fed silage from corn harvested at the black layer stage (9 kg/d), intake of digestible starch was 0.4 kg/d lower for cows fed silage from corn harvested at the black layer stage. The optimum stage for corn that was ensiled was two-thirds milkline with some flexibility between quarter and two-thirds milkline. PMID- 9361222 TI - The effect of dietary energy source during mid to late lactation on liver triglyceride and lactation performance of dairy cows. AB - Control [1.61 Mcal of net energy for lactation (NEL)/kg of dry matter (DM)], high grain (1.70 Mcal of NEL)/kg of DM), or high fat [1.70 Mcal of NEL/kg of DM with 2.3% tallow (DM basis)] diets were fed to 43 cows (150 +/- 3.1 d in milk) during mid to late lactation to determine effects on performance characteristics, metabolic parameters, or both during mid to late lactation, the dry period, and the first 100 d of the next lactation. All cows received identical diets during the dry period and during early lactation. Increasing the energy density of the diets during mid to late lactation increased DM intake (DMI), plasma nonesterified fatty acid concentration, milk production, and milk protein yield. Compared with the high grain diets, fat supplementation decreased DMI and the percentage of milk protein but increased plasma nonesterified fatty acid concentration without causing elevation of liver triglyceride at the end of mid to late lactation. Increased energy density of the diets did not affect body condition score during mid to late lactation. There were no residual effects for any of the treatments on DMI, lactation performance, or body weight in the subsequent lactation. However, energy supplementation during mid to late lactation increased liver triglyceride content after calving. Compared with high fat diets, high grain diets fed during mid to late lactation increased plasma beta-hydroxy-butyrate concentration in the subsequent lactation. High energy diets fed during mid to late lactation may influence lipid metabolism during the following lactation. PMID- 9361223 TI - Effects of the energy balance of dairy cows on lactational responses to rumen protected methionine. AB - This trial was designed to investigate the interactions between level of dietary energy and the response of cows after supplementation of rumen-protected Met. We examined this interaction for dairy cows fed a diet that was deficient in Met. Two percentages of energy (87 or 100% of requirements) were supplied with two concentrations of rumen-protected Met (0 or 21 g/d). Twenty-four Holstein cows (58 d in milk) were assigned to an experiment with a split-plot design including five periods of 3 wk each. The lower energy level was obtained by limiting the amount of feed offered (18.4 vs. 20.1 kg of dry matter intake). Diets characterized by low or normal amounts of energy were composed of corn silage (69.4% vs. 69.7%), energy concentrate (18.5% vs. 22.1%), oil meals treated with formaldehyde (11.5% vs. 7.4%), and urea (0.8% vs. 1.0%), respectively. The interaction between energy level and Met supplementation did not affect yield or composition of milk. An increase in the supply of both energy and Met increased the true protein content of milk by 0.11 percentage units. The effects of the level of dietary energy on the protein content of milk augmented the effects caused by Met supplementation. The main practical conclusion was that rumen protected Met can be used with diets based on corn silage and soybean meal to increase the protein content of milk, even for dairy cows that are in a negative energy balance. PMID- 9361224 TI - Increased weight gain and effects on production parameters of Holstein heifer calves that were allowed to suckle from birth to six weeks of age. AB - Forty Holstein heifer calves were assigned to two treatments. Control calves (n = 20) were fed milk replacer in open buckets, and calves that were allowed to suckle (n = 20) were paired and suckled the same dam three times daily. Treatments were conducted during the first 6 wk following birth; thereafter, all calves received the same management, and weaning was at 60 d of age. During treatment, calves that were allowed to suckle had significantly higher average daily gains than did control calves. However, at 12 wk of age, calves that were allowed to suckle had significantly lower body weights (BW) than did control calves. Age at conception was significantly lower, and BW at conception and conception rate tended to be higher, for calves that were allowed to suckle. Calving age was significantly earlier for heifers that had been allowed to suckle as calves, and BW at calving also tended to be higher. Height at the withers after calving was also significantly higher for those heifers. Milk production during first lactation tended to be higher for the heifers that had been allowed to suckle as calves. Our results indicated that heifer calves that suckled milk during the first 42 d of age had higher average daily gains, higher height at the withers, an earlier age at calving, and a tendency for greater milk production than did calves fed milk replacer. PMID- 9361225 TI - An evaluation of two management systems for rearing calves fed milk replacer. AB - In two experiments, 54 dairy calves were allotted to one of two management systems. One-half of the calves was raised under a conventional system that consisted of housing in separate calf hutches and manually feeding milk replacer twice daily until weaning at 7 to 8 wk of age. In this system, calves had ad libitum access to a starter diet. The remainder of the calves was housed in a single group pen and was fed via a computerized system that allowed controlled access to milk replacer and starter for 24 h/d. In both experiments, average daily gain and final body weight at weaning were similar between management systems. In Experiment 2, calves that were fed milk replacer via the automated system consumed more starter diet during the 2nd and 3rd wk, but consumed less starter during wk 6 and 7; however, total consumption of the starter diet prior to weaning was not different between treatments. Calves in the group pen had fewer days of medication than did those in hutches. The time needed to manage a calf in a hutch amounted to approximately 10 min per calf, but the time committed to management of a calf raised in the group pen was < 1 min/d. A 200-cow dairy herd with a 35% yearly cull rate and a mean calf mortality rate of 10% would regain costs of initial investment for the computer feeder by savings in labor within 2 to 3 yr. PMID- 9361226 TI - A new method of measuring diet abrasion and its effect on the development of the forestomach. AB - Twelve newborn Holstein bull calves were used to evaluate the effects of dietary abrasiveness, determined by a new method, on ruminal development. Calves were blocked by age and body weight and were assigned to one of three different diets. Each diet had the same ingredients but different particle sizes, which resulted in different abrasive values. No differences were detected in molar percentages of volatile fatty acids in ruminal fluid or in plasma concentrations of urea, glucose, or beta-hydroxybutyrate. The pH of ruminal fluid was lower for calves fed the fine and intermediate diets than for those fed the coarse diet. Digesta free weights of the stomach and stomach compartments were similar among calves fed the three diets, except that omasum weights were heavier for calves fed the fine diet. Length of the ruminal papillae increased as the abrasive value of the diet decreased. Measurements of ruminal tissue layers from the ventral floor of the cranial sac were not different among diets, but the keratin portion represented more of the epithelial layer for calves fed the diet with the lowest abrasive value, thus decreasing the percentage of metabolically active tissue for those calves. PMID- 9361228 TI - Partial genomic structure of the bovine CD18 gene and the refinement of test for bovine leukocyte adhesion deficiency. PMID- 9361227 TI - Using dry feed intake as a percentage of initial body weight as a weaning criterion. AB - Newborn Holstein heifers (n = 32) and bulls (n = 12) were used to investigate the use of dry feed intake as a percentage of birth weight as a weaning criterion. Three different percentages (1, 1.5, and 2%) were used. Calves in the 1% treatment group met the weaning criterion earlier than did those in the 1.5 and 2% treatment groups; no difference was detected between the latter two groups. Total dry feed intake at 8 wk was higher for calves in the 1% treatment group than for calves in the other treatment groups; no difference was detected between the 1.5 and 2% treatment groups. Weights for all calves at 8 wk and weights of heifer calves at 12, 16, and 20 wk were not different among groups. Using dry feed intake at 1% of birth weight as a weaning criterion reduced days to weaning, increased dry feed intake from birth to 8 wk, decreased variation in weaning age, and had no apparent negative effect on growth at 20 wk of age. Using dry feed intake as a percentage of birth weight appears to be a suitable criterion to determine when to wean dairy calves. PMID- 9361229 TI - Comparison of possible covariates for use in a random regression model for analyses of test day yields. AB - Random regression models have been proposed for the genetic evaluation of dairy cattle using test day records. Random regression models contain linear functions of fixed and random coefficients and a set of covariates to describe the shapes of lactation curves for groups of cows and for individual cows. Previous work has used a linear function of five covariates to describe lactation shape. This study compared the function of five covariates with a function of only three covariates in three random regression models. Comparisons of estimates of components of variances and covariances, as well as comparisons of EBV and their prediction errors for milk yield, were made among models. Small practical differences existed between models in all respects. The model using regressions with five covariates had a slight advantage for comparison of prediction error variances of daily yields. PMID- 9361230 TI - Effect of live weight and differing economic values on responses to selection for milk fat, protein, volume, and live weight. AB - Five traits of major economic importance in the New Zealand dairy industry are milk volume, milk fat, milk protein, live weight, and survival. This study evaluated the impact of live weight as a trait in the selection objectives for the New Zealand dairy industry. Live weight of the lactating cow is an important measure because it reflects feeding costs via maintenance feed and salvage values of cows to be culled. In addition, selection responses were evaluated for differing relative economic values for milk protein and milk fat, and selection indexes that included or excluded phenotypic and genotypic correlations between traits were compared. Inclusion of live weight, with a negative economic value in a four-trait selection index with milk, milk fat, and protein resulted in higher economic response. Protein response to selection was not more than 2% when the relative economic value for the ratio of protein to milk fat exceeded 5:1 in a two-trait model; however, milk fat response decreased by over 10%. When a negative relative economic value was assigned to milk fat, economic returns were lower because of lower milk fat responses and the lack of higher protein responses compared with the same ratio for relative economic value but a positive weight for milk fat. Accounting for phenotypic and genetic correlations in deriving selection index weight improved economic response 5%. PMID- 9361231 TI - Application of canonical transformation with missing values to multitrait evaluation of Jersey type. AB - A multitrait animal model was used to calculate predicted transmitting ability and reliabilities for final score and 15 linear type traits of 225,632 US Jersey cows. Records were adjusted for age and stage of lactation before analysis. The model contained effects for interactions of herd and date scored; year scored, parity, and age; and herd and sire; effects of permanent environment and additive genetics were also included. Of the 381,511 records included, some observations were missing for final score (8%), body depth (43%), and teat length (33%). The evaluation system used a canonical transformation, included several random effects, and estimated missing values with each iteration. Inbreeding was considered in the computations. Convergence was achieved in approximately 50 rounds of iteration. Correlations between animal and sire model predicted transmitting ability ranged from 0.56 to 0.95 and generally were higher for bulls than for cows and for more recent birth years. Genetic trend was strongly positive for dairy form, final score, and rear udder traits (height and width) and negative for udder depth. For other traits, genetic trend was small. This methodology should improve the accuracy of genetic evaluations for type traits of US Jerseys. PMID- 9361232 TI - Analysis of productive life in Swiss brown cattle. AB - An analysis of productive life of Swiss Brown cattle was performed using a mixed survival model based on Cox regression. Data included 52,862 daughters of 297 sires. The length of productive life was observed from May 1, 1985 through August 15, 1995. Records on cows that were still alive in the end of study (32.4%) were treated as censored. The probability of being culled (hazard) was defined as a product of a baseline hazard function and a function of explanatory variables. In addition to sire effects, the model included effects of age at first calving and the time-dependent variables herd by year, lactation number, stage of lactation, and milk production within the herd to account for culling because of low production. Solutions for fixed effects indicated a higher probability of being culled for primiparous cows, for cows in the end stage of lactation, and for cows with low production. The impact of censoring on the accuracy of estimation was investigated by computing the rank correlations between the estimated transmitting abilities (ETA) of sires using a simplified model from uncensored data (reference) and the ETA from several different data files with an increased proportion of censored records. The rank correlations among sire ETA decreased as number of daughters per sire decreased and as the proportion of censored records increased. The maximum number of censored records that is acceptable to obtain accurate results is 30 to 40%. The acceptable proportion of censored records would be higher if the reference ETA were obtained on a larger data file using daughters of old sires. PMID- 9361233 TI - A two-stage half-sib design for mapping quantitative trait loci in food animals. AB - Daughter and granddaughter half-sib designs for mapping quantitative trait loci were modified to increase experimental power. This new design includes a two stage procedure, in contrast to conventional one-step half-sib designs. In stage 1, a few progeny of each sire are genotyped for marker loci. Based on the analyses of stage 1 data, some sires are chosen to continue genotyping more progeny for stage 2. When multiple chromosomes are under investigation, chromosomes and sires for stage 2 are selected based on the analysis of stage 1 data. Sire selection results in increased frequency of heterozygous genotypes of interest in stage 2 if the markers are linked to those genes. Chromosome selection can increase the proportion of chromosomes with segregating quantitative trait loci in stage 2 if not all of the chromosomes evaluated in stage 1 have segregating quantitative trait loci. Numerical results indicated that two-stage half-sib designs are generally more powerful than conventional designs when 1) the noncentrality parameter is moderate or larger, 2) larger quantitative trait loci are mapped using tightly linked markers in larger families, and 3) variation is large in numbers and sizes of segregating quantitative trait loci among the chromosomes evaluated in stage 1. PMID- 9361234 TI - Bovine mastitis pathogens in New York and Pennsylvania: prevalence and effects on somatic cell count and milk production. AB - Milk samples were collected from 108,312 dairy cows during 1601 farm visits made between January 1991 and June 1995. The herd visits were made by personnel from the Central Laboratory of the Quality Milk Promotion Services at Cornell University (Ithaca, NY) to farms located in central New York and northern Pennsylvania. Dairy Herd Improvement Association records were available for 32,978 cows in 327 herds. Intramammary infections, as defined by positive milk cultures, were present in 48.5% of all cows and in 36.3% of cows in herds enrolled in the Dairy Herd Improvement Association. Over 75% of the intramammary infections were caused by Streptococcus agalactiae, Streptococcus spp. other than Strep. agalactiae, Staphylococcus aureus, and coagulase-negative staphylococci. Mean days in milk at the time of diagnosis, linear score of the somatic cell count, cost of milk loss per lactation, and milk production effects were calculated for 24 etiologic agents of bovine mastitis. PMID- 9361235 TI - Usability for genetic evaluations of records from herds participating in progeny test programs of artificial insemination organizations. AB - Thirteen AI organizations provided identification of herds that participated in their progeny test programs in 1989 and 1990; 15% of those herds participated in programs of more than one AI organization, but only 2.6% participated in programs of more than two AI organizations. Of the 19,589 participating herds, 82 and 76% were enrolled in DHI test plans that were considered to be usable for genetic evaluations during 1991 and 1992. For herds that had participated in AI progeny test programs, mean percentages of usable records were 77% in 1991 and 78% in 1992; the mean percentages of usable records for nonparticipating herds were 62% in 1991 and 60% in 1992. Participating herds had larger mean herd sizes, higher means and standard deviations of milk yields, younger cows, and a lower percentage of registered cows than did nonparticipating herds. Analysis of variance was used to explain the variation in the percentage of records that were usable for genetic evaluations. Herds that participated in AI progeny test programs or that had smaller herd sizes, higher mean milk yields, younger cows, or larger percentages of registered cows had higher percentages of records that were usable for genetic evaluations. Improved usability of records for genetic evaluations would increase the efficiency of AI progeny testing, and consideration of herd characteristics associated with higher percentages of usable records should aid AI organizations in evaluating prospective herds for progeny test programs. PMID- 9361236 TI - Trends in research for alternate uses of milk fat. AB - During the past 2 yr, sales of butter have increased, and the inventory of milk fat in the US has decreased. However, still fresh in memory are the large inventories of butter and low prices for milk fat. Although economic peaks and valleys are a result of consumer preferences, research in the area of milk lipids is very active. This paper is a limited review of the continuing research trends and technological advances in the field of lipids, particularly milk fat. The modification of milk fat composition through cattle nutrition, fractionation by melt crystallization and supercritical fluid extraction, blending, interesterification, and glycerolysis as well as the emerging importance of analysis of lipids are some of the areas for which active research promises future advances in milk fat technology. PMID- 9361237 TI - Manure management. A systems approach. AB - Traditionally, the management of manure nutrients has focused primarily on the production, collection, storage, and field application of manure. By contrast, a total systems approach expands this focus to include concerns about human and animal health, odor and fly control, nutrient import and handling, ration balancing and feeding management to optimize dietary nutrient utilization, management of crop harvest and storage to maximize feed palatability and nutrient digestibility, manure processing for export, farm economics of nutrient management, and the broader economic impacts of environmental regulation and enforcement. In the future, the focus of manure and nutrient management must be to optimize nutrient flow and utilization at every point within the total dairy farm system. A total systems approach to nutrient management is vital to the future of the dairy industry. This approach requires a broad spectrum of scientific expertise that includes multidisciplinary teams involving agronomists, dairy scientists, economists, engineers, microbiologists, soil scientists, veterinarians, and regulators to deal successfully with the complex issues pertaining to dairy nutrient management. PMID- 9361238 TI - Nuisance concerns and odor control. AB - Nuisance and odor control continue to be major challenges to livestock and poultry producers across the country. Dust and flies are the two most frequently mentioned nuisances after odors. Research and testing have devised systems that are capable of achieving reduced frequency and intensity of odors, flies, and dust; however, these systems are typically more expensive to build and operate than is the standard lagoon holding basin. Producers who operate close to sensitive odor perception sites are at a clear disadvantage to those located in more remote locations. In addition to the cost factor is the uncertainty associated with nuisance and odor control. Some dairies are able to co-exist with their neighbors despite frequent odor detection, but others find that their neighbors demonstrate much less tolerance. Odor control additives, either fed or applied to the manure, have generally been less than fully successful. Careful site selection, appropriate facility design, flawless management, and a generous amount of positive local relations have proved to be the most effective means of avoiding cost from odor confrontations. PMID- 9361239 TI - Manure and microbes: public and animal health problem? AB - Most environmental concerns about waste management either have focused on the effects of nutrients, especially N and P, on water quality or have emphasized odor problems and air quality. Microbes from manure are often low on the priority list for control and remediation, despite the fact that several outbreaks of gastroenteritis have been traced to livestock operations. The pathogens discussed in this paper include protozoans (Cryptosporidium parvum, Giardia spp.), bacteria (Listeria monocytogenes, Escherichia coli O157:H7, Salmonella spp., and Mycobacterium paratuberculosis), and some enteric viruses. Clinical symptoms, prospects for zoonotic infection, and control methods other than the use of antimicrobials are considered. Recommendations to avoid disease transmission include taking steps to ensure the provision of clean, unstressful environments to reduce disease susceptibility and the careful handling and spreading of manure from animals at high risk for infection, especially young calves. Composting and drying of manure decrease the number of viable pathogens. Environmental controls, such as filter strips, also reduce the risk of water contamination. PMID- 9361240 TI - Graft arteriosclerosis-induced myocardial pathology in heart transplant recipients: predictive value of endomyocardial biopsy. AB - BACKGROUND: Ischemic myocardial pathology resulting from graft arteriosclerosis (GA) includes subendocardial myocyte vacuolization (SEMV), indicative of sublethal ischemic injury, and coagulative myocyte necrosis, acute and healing (CMN), indicative of infarction. METHODS: To assess the sensitivity and specificity of myocardial pathology resulting from GA in endomyocardial biopsy specimens, we correlated SEMV and CMN in the final three biopsy specimens (mean interval from last biopsy to death 23 +/- 20 days) with autopsy findings from 30 heart transplant recipients who survived more than 3 months and died of GA (n = 16) or of other causes (n = 14). The two groups were similar in other parameters. RESULTS: Myocardial ischemic injury was present at autopsy in all 16 patients with GA with the following distribution: SEMV (n = 13) nine right ventricle (RV) and left ventricle (LV), four LV only; focal CMN (n = 8) six RV and LV, two LV only; subendocardial infarct (n = 3) three LV only; and transmural infarct (n = 3) one RV, two LV. Ischemic injury was present in the RV of 11 of 16 patients with GA. Of patients without GA, one had SEMV at autopsy; none had infarcts. Ischemic myocardial pathology was present in 10 of 48 biopsy specimens from patients with GA compared with one of 41 biopsy specimens from patients without GA (p < 0.05). The specificity of SEMV on biopsy was 98%, but sensitivity was only 17%. The positive predictive value for ischemic injury was 92%, and negative predictive value was 51%. CONCLUSIONS: Myocardial pathology resulting from ischemia was present at autopsy in all patients dying of GA. Although more prevalent in the LV, 69% of patients had ischemic myocardial pathology in the RV, where it may be accessible to biopsy. Ischemic myocardial pathology in biopsy specimens is highly specific but far less sensitive, for diagnosing GA. PMID- 9361241 TI - Type and extent of myocardial injury related to brain damage and its significance in heart transplantation: a morphometric study. AB - BACKGROUND: Focal myocardial necrosis reported in patients who died of brain lesions and in donor hearts soon after insertion has been attributed to catecholamine-related injury induced before operation, or in the perioperative period. Interpretation of the morphofunctional type of myocardial injury observed and its quantification may help understand both its pathophysiology and clinical relevance. METHODS: In 27 patients without heart disease who died of intracranial brain hemorrhage after berry aneurysm rupture, terminal clinical signs were correlated with the presence of absence of myocardial injury. All hearts were systematically examined, and the total histologic area was measured in square millimeters, with both the number of foci and myocardial cells showing necrosis, normalized to 100 mm2. Forty-five cases of fatal head trauma (26 "instantaneous" and 19 "rapid" deaths) in normal subjects and 38 cases of acquired immunodeficiency syndrome with (14 cases) or without (24 cases) severe brain damage were used as control subjects. RESULTS: Contraction band necrosis was the only form of myocardial necrosis found in 89% of patients with acute brain hemorrhage. Its extent was 26 +/- 34 foci and 67 +/- 104 necrotic myocardial cells x 100 mm2. In patients with acquired immunodeficiency syndrome, its frequency was 58% in those without and 78.5% with severe brain lesions, with foci and myocardial cell values of 1 +/- 1.5 and 10 +/- 22 and 7 +/- 16 and 17 +/- 32, respectively. In head trauma cases with instantaneous death, the frequency was 4% (one case only with foci 0.5 and myocardial cells 35), whereas with a rapid death it was 40% (foci 12 +/- 18 and myocardial cells 21 +/- 33). CONCLUSIONS: The observed myocardial injury was present in all groups examined, being maximal in patients with intracranial brain hemorrhage with longer survival and minimal in patients with head trauma who died instantaneously. In this setting, this lesion is typical of catecholamine myotoxicity and may express a sympathetic overstimulation either in the agonal period and independent of therapy or be caused by brain injury, especially intracranial brain hemorrhage. However, the extent of myocardial injury observed was minimal and should not jeopardize cardiac function if hearts from such subjects are transplanted. PMID- 9361243 TI - Exercise-induced ventilatory abnormalities in orthotopic heart transplant patients. AB - STUDY OBJECTIVE: The purpose of this investigation was to compare multiple ventilatory responses of heart transplant patients (HTP) with normal subjects (NL) at rest, at absolute and relative submaximal exercise levels, and at peak exercise. DESIGN: Ten male HTP and 10 matched NL were tested under similar conditions on a treadmill with the use of an incremental protocol to symptom limited maximal levels while breath-by-breath measurements of gas exchange and ventilation were obtained. RESULTS: At an absolute carbon dioxide (VCO2) level of 1 L.min-1, minute ventilation (VE) was significantly higher in HTP compared with NL (38.4 +/- 1.9 versus 29.3 +/- 0.9 L.min-1). However, when compared at similar relative levels (i.e., 40% and 60% of the peak oxygen consumption [VO2 peak]), VE was found to be significantly higher in NL compared with HTP (25.5 +/- 1.4 versus 21.2 +/- 1.0 L.min-1 at 40%; 39.9 +/- 3.1 versus 32.1 +/- 2.0 L.min-1 at 60%, respectively). The reduced VE was the result of a significantly lower tidal volume (VT) in HTP compared with NL at 40% (1.14 +/- 0.08 versus 1.33 +/- 0.05 L) and 60% (1.40 +/- 0.10 versus 1.85 +/- 0.06 L) of VO2 peak, since breathing frequency (BF) was not different between the groups at these levels. CONCLUSIONS: These data demonstrate that HTP have abnormal ventilatory responses to incremental exercise that are largely explained by a diminished VT response. While mechanical factors known to affect VT cannot be ignored, it is likely that the abnormal VT response of HTP during exercise is secondary to respiratory muscle weakness and may be due to hypoperfusion, long-term deconditioning, and/or the long-term use of corticosteriods. PMID- 9361242 TI - FK506 effectiveness in reducing acute rejection after heart transplantation: a prospective randomized study. AB - BACKGROUND: Tacrolimus (FK506) has recently become available clinically as an alternative to cyclosporine-based immunosuppression. This study reports the middle-term results of a prospective, randomized trial that compared FK506 with cyclosporine-based immunosuppression in heart transplant recipients. METHODS: Twenty-five consecutive patients were randomized at a 2:1 ratio into two groups, one of which received FK506 (15 patients), the other cyclosporine (10 patients). Both groups received similar concomitant immunosuppression. The patients were followed up for 12 months. The following outcome parameters were analyzed: survival, rejection and infection rate, lymphocyte subsets, new-onset diabetes, renal and hepatic function, hypertension, right-sided heart catheterization data, graft coronary artery disease, and neurologic side effects. RESULTS: The mortality rate (two patients) in the FK506 group was 13% versus 0% in the cyclosporine group (p = NS). The two deaths were the consequences of early infections and higher doses of FK506. From the outset, the FK506 group presented a lower prevalence of acute rejection, a lower requirement for rejection treatments and a higher incidence of infections. Accordingly, we reduced overall immunosuppression for the last seven patients in the FK506 group; the decrease in FK506 and prednisone dosage led to a decrease in the early infection rate without an increase in the rejection rate. There was no difference between the two groups in diabetes incidence, renal and hepatic function, right-sided heart catheterization data, or coronary angiograms. Hypertension was less frequent and milder in the FK506 group. CONCLUSIONS: This experience suggests that FK506 can be safely used in heart transplantation. It can decrease the frequency of rejection episodes. Low-dose administration allows a lower infection rate without an increase in rejection. With a protocol of delayed starting and low dosing, side effects such as renal toxicity, hypertension, and neurologic toxicity seem to be unlikely. Further studies are needed to establish the exact dosage and therapeutic levels of the drug. PMID- 9361244 TI - Retrospective risk analysis for early heart-related death after cardiomyoplasty. The Worldwide Cardiomyoplasty Group. AB - BACKGROUND: Dynamic cardiomyoplasty is an evolving treatment for heart failure that uses an electrically stimulated latissimus dorsi muscle wrapped around the heart to improve cardiac function. Preoperative patient characteristics and deaths after cardiomyoplasty have been recorded during the past 5 years in a cumulative database representing worldwide experience of 42 medical centers. METHODS: Statistical models of hazards (monthly death rates) were used to identify risk factors for transiently increased risk of cardiovascular mortality within 2 months after cardiomyoplasty. RESULTS: Actuarial survival (n = 261) was 88%, 80%, and 76% at 1, 3, and 6 months after cardiomyoplasty, respectively. The peak hazard of 6% dying per month occurred during the first month after the surgical procedure. Lower ejection fraction, increased number of major coronary arteries with > or = 70% stenotic lesions, and lower chronotropic responses during exercise were independent risk factors for the transient increase in early cardiovascular mortality. Early risk of cardiovascular mortality was significantly reduced as centers gained experience with more than 3 patients. CONCLUSION: Early survival after cardiomyoplasty has improved with experience and might be reduced further by preoperative assessments that identify patients at highest risk. PMID- 9361245 TI - Defective endogenous nitric oxide-mediated modulation of cellular respiration in canine skeletal muscle after the development of heart failure. AB - BACKGROUND: It is well documented that nitric oxide (NO) suppresses the function of a number of mitochondrial enzymes. Our recent studies found that endogenous NO may play an important role in the modulation of tissue oxygen (O2) consumption and cellular respiration both in vitro and in vivo. METHODS: Tissue O2 consumption was measured by a Clark-type O2 electrode at 37 degrees C in freshly isolated skeletal muscle segments from the accessory head of the triceps brachii (90% type I muscle fiber) and extensor carpi radialis (86% type II muscle fiber) from normal dogs and dogs with tachycardia-induced heart failure. RESULTS: S nitroso-N-acetylpenicillamine (SNAP), carbachol, and bradykinin at doses of 10( 7) to 10(-4) mol/L concentration significantly suppressed tissue O2 consumption both in the absence and presence of 2,4-dinitrophenol (1 mmol/L), a mitochondrial uncoupler. These effects were not significantly different in the accessory head of the triceps brachii (90% type I muscle fiber) and extensor carpi radialis (86% type II muscle fiber). The effects of carbachol and bradykinin but not SNAP were attenuated by NG-nitro-L-arginine (10(-4) mol/L), indicating inhibition of the formation of endogenous NO. The inhibitory effect on tissue O2 consumption in response to carbachol and bradykinin became significantly smaller in skeletal muscle from dogs with pacing-induced heart failure, but the effects of SNAP were unchanged. CONCLUSIONS: Endogenous NO released from microvascular endothelium may play an important physiologic role in the modulation of cellular respiration in skeletal muscle, and the loss of this regulatory function may contribute to peripheral metabolic disorders and poor exercise tolerance during heart failure. PMID- 9361246 TI - Low multiplicity cytomegalovirus infection of human aortic smooth muscle cells increases levels of major histocompatibility complex class I antigens and induces a proinflammatory cytokine milieu in the absence of cytopathology. AB - BACKGROUND: Cytomegalovirus has been implicated in the development of allograft vasculopathy in heart transplant recipients. Given that allograft vasculopathy is a form of chronic rejection, it is conceivable that cytomegalovirus somehow alters the allogeneic response to the vasculature. Prior work has demonstrated that smooth muscle cells (SMCs) are highly permissive for cytomegalovirus and exhibit cytopathologic characteristics and alterations in MHC class I antigens in response to cytomegalovirus at a high multiplicity of infection (MOI). METHODS: To determine whether cytomegalovirus at low, more clinically relevant MOI, can alter SMCs phenotypically, human aortic SMCs were infected with approximately 1 plaque forming units/3000 cells of cytomegalovirus strain AD169. RESULTS: One week after infection, human aortic SMCs (compared with human foreskin fibroblasts) demonstrated no cytopathologic characteristics (n = 6), released reduced amounts of intact virion into the culture media (assessed by exposing naive monolayers of human foreskin fibroblasts to media and staining for cytomegalovirus immediate-early antigen, n = 3), yet had at least, if not greater detectable total cytomegalovirus vital DNA levels. Infected HASMCs uniformly increased their expression of MHC class I antigen by 55% +/- 21% above constitutive levels (assessed by flow cytometry (n = 5, p < 0.0001). Cytomegalovirus infection resulted in an increase in interleukin-6 mRNA expression compared to control (297 +/- 63 vs 188 +/- 50, respectively; p = 0.02, n = 6) and reduced the expression of transforming growth factor-beta mRNA (802 +/ 152 vs 1201 +/- 236, respectively; p = 0.05). CONCLUSIONS: These data suggest that low MOI of cytomegalovirus can infect SMCs without producing cell cytolysis and, in spite of this lack of overt infection, modulate cell surface antigens and cytokine mRNA levels that can influence allogeneic responses. PMID- 9361247 TI - Serial measurements of interleukin-6, interleukin-8, tumor necrosis factor-alpha, and soluble vascular cell adhesion molecule-1 in the peripheral blood plasma of human cardiac allograft recipients. AB - BACKGROUND: Cardiac allograft rejection is largely an inflammatory response that, if allowed to proceed unchecked, will result in hemodynamic compromise or cardiogenic shock. Soluble mediators produced during an inflammatory response could potentially provide information regarding the initiation, progression, and outcome of a rejection episode. To test this hypothesis, we investigated the use of plasma cytokine measurements for interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor alpha (TNF alpha) in combination with measurements of soluble vascular cell adhesion molecule-1 (VCAM-1), an adhesion molecule, as a means for the detection of cardiac allograft rejection. METHODS: Serial enzyme linked immunosorbent assays were performed on plasma samples collected from 29 patients three times per week during the first 8 weeks after transplantation. RESULTS: IL-6 plasma concentrations increased fivefold in the first week after transplantation (p < 0.001 vs pretransplantation levels) and thereafter remained at low levels for the next 6 weeks, with a small increase during the 8 weeks after transplantation (p = 0.006). In contrast, TNF-alpha, IL-8, and VCAM-1 levels remained low during the first 6 weeks after transplantation followed by a rise in mean VCAM-1 levels from 841 +/- 38 to 979 +/- 52 ng/ml at week 8. To determine the relationship of levels of each of the four soluble factors with rejection, the mean values obtained during the time interval 1 to 5 days before rejection were compared to mean values obtained during rejection and at other periods of no rejection (baseline). Cytokine levels were not predictive of rejection (no difference in levels 0 to 5 days before rejection versus baseline, p > 0.3 for IL-6, IL-8, TNF-alpha). However, VCAM-1 levels increased 0 to 5 days before rejection compared with baseline (914 +/- 40 vs 844 +/- 30 ng/ml, p = 0.06). CONCLUSIONS: IL-6 levels are increased immediately after heart transplantation. Circulating IL-6, IL-8, and TNF alpha levels do not predict rejection during the first 8 weeks after transplantation. Soluble VCAM-1 increases within 5 days before rejection and may potentially serve as a noninvasive marker for early rejection. PMID- 9361248 TI - Carbohydrate selectin inhibitor CY-1503 reduces neutrophil migration and reperfusion injury in canine pulmonary allografts. AB - BACKGROUND: Neutrophil adhesion is initiated by the interaction of rapidly expressed endothelial selectins with oligosaccharide structures (sialyl Lewis(x) on polymorphonuclear neutrophils (PMN). The carbohydrate sialyl Lewis X analogue CY-1503 blocks selectin receptors, thereby inhibiting PMN rolling and subsequent firm adhesion and migration. METHODS: We evaluated the inhibitory effect of CY 1503 on PMN migration and reperfusion injury in canine left lung allografts. Donor lungs were flushed with modified Euro-Collins solution (1500 ml, 4 degrees C) and preserved for 21 hours at 1 degree C. Left lung allotransplantation was subsequently performed in 14 mongrel dogs. Immediately after transplantation and allograft reperfusion, the recipient contralateral right pulmonary artery and bronchus were ligated to permit assessment of isolated allograft function during a 6-hour postreperfusion period (FIO2 = 1.0). Allograft gas exchange (q 15 minutes) and hemodynamics (q 60 minutes) were assessed. After sacrifice, allograft bronchoalveolar lavage fluid (BALF) PMN count and allograft tissue myeloperoxidase (MPO) activity were measured. Two groups were studied: In group I (n = 7) CY-1503 was added to the donor lung flush (20 mg/L) and given to the recipient (35 mg/kg intravenous bolus) before reperfusion, followed by a continuous infusion (5.25 mg/kg/h intravenously) during the 6-hour assessment period. Group II animals (n = 7) received no CY-1503. RESULTS: Gas exchange in group I was superior throughout the assessment period (p < 0.01 at 6 hours after reperfusion). BALF PMN count in group I was reduced to 0.57 +/- 0.3 x 10(6) PMN/ml compared with 3.9 +/- 1.3 x 10(6) PMN/ml in group II (p < 0.05). Group I allograft MPO activity was 0.21 +/- 0.06 compared with 0.40 +/- 0.02 delta OD/mg/ min in controls (p < 0.02). Two animals in each group died early after reperfusion as a result of graft failure and were excluded from analysis. CONCLUSIONS: Our observations indicate that selectin inhibition effectively reduces PMN adhesion, migration, and subsequent reperfusion injury in preserved canine lung allografts. PMID- 9361249 TI - The effects of FR167653 on pulmonary ischemia-reperfusion injury in dogs. AB - BACKGROUND: Ischemia-reperfusion injury may result in the local release of proinflammatory cytokines. A newly synthesized organic compound, FR167653, has been characterized as a potent suppressant of interleukin-1 beta and tumor necrosis factor-alpha. We investigated the effects of FR167653 on ischemia reperfusion injury of the lung by using an in situ warm lung ischemia model in dogs. METHODS: Thirteen dogs were divided into two groups; seven dogs were assigned to the control group, and six were assigned to the FR167653-treated group. The latter group was administered FR167653 (1 mg/kg/hr) continuously beginning 30 minutes before induced ischemia and ending 2 hours after reperfusion. Warm ischemia was induced for 3 hours by clamping the pulmonary artery and veins. The left main bronchus was bisected and anastomosed 3 hours later. Arterial oxygen saturation, left pulmonary vascular resistance, and cardiac output were measured. Blood was collected to measure interleukin-1 beta level, and the lung specimen was harvested for histologic study. RESULTS: Arterial oxygen saturation levels after 30 minutes and 2 hours of reperfusion were significantly (p < 0.05) higher in the FR167653-treated group than in the control group. After 30 minutes of reperfusion, cardiac output deterioration was significantly (p < 0.05) greater in the control group than in the FR167653 treated group, and left pulmonary vascular resistance was significantly (p < 0.05) lower in the FR167653-treated group than in the control group. The 3-day survival rate was 67% in the FR167653-treated group and 14% in the control group. There were statistically significant differences (p < 0.05) between the survival rates of the two groups. Alveolar damage with interstitial edema and hyaline membranes localized along the alveolar duct were observed in the control group; whereas reduced interstitial edema was observed in the FR167653-treated group. Blood levels of IL-1 beta were lower in the FR167653-treated group than in the control group. CONCLUSION: FR167653 seems to generate a protective effect relative to ischemia-reperfusion injury of the lung in the early stage of tissue damage. PMID- 9361251 TI - Insufficiency fractures of the sacrum: a cause of low back pain after lung transplantation. AB - Insufficiency fractures of the sacrum were diagnosed during the first year after successful transplantation in four (5.6%) of 71 lung and heart-lung transplant recipients. Each patient had development of low back pain after minor or no trauma; all had osteoporosis. In each instance, plain radiographs failed to demonstrate the fracture, and the diagnosis was established by radionuclide bone scanning that demonstrated the characteristic "butterfly" (bilateral sacral fracture) or "half-butterfly" appearance (unilateral sacral fracture). Sacral insufficiency fractures, a significant cause of low back pain in lung transplant recipients, may be underdiagnosed in this population because routine radiographs do not usually reveal the fracture; bone scanning is the preferred diagnostic modality. PMID- 9361250 TI - Preharvest nitroprusside flush improves posttransplantation lung function. AB - BACKGROUND: Morbidity as a result of early allograft dysfunction remains a significant problem in clinical lung transplantation. We previously demonstrated that nitroprusside (NP), a potent nitric oxide donor, administered before storage and again during reperfusion, reduced lung reperfusion injury. The purpose of the present study was to determine whether these observations were storage effects, reperfusion effects, or both. MATERIALS AND METHODS: Fifteen dogs underwent left lung allotransplant. Donor lungs were flushed with modified Euro-Collins solution and stored for 21 hours at 1 degree C. Immediately after transplantation, the contralateral right main pulmonary artery and bronchus were ligated to assess isolated allograft function. Hemodynamics and arterial blood gas analysis (FIO2 1.0) were assessed for 6 hours before sacrifice. Allograft myeloperoxidase (MPO) activity and wet to dry weight (W/D) ratio were assessed. Animals were divided into three groups for timing of NP administration. Group I (n = 5) animals received no NP. In group II (n = 5), donor lungs received NP (10 mg/L) in the flush solution only. In group III (n = 5), recipient animals received NP (0.2 mg/kg) just before reperfusion, as well as a continuous infusion (0.1 mg/kg/hr) during the assessment period. RESULTS: Significant improvement in gas exchange was apparent in groups II and III compared with group I, but there was no significant difference between groups II and III. After 6-hour reperfusion, mean PaO2 values were 85.46 +/- 13.32 mm Hg in group I, 298.74 +/- 61.25 mm Hg in group II (p < 0.05), and 311.12 +/- 43.39 mm Hg in group III (p < 0.05). Systemic vascular resistance was significantly lower in group III than in group I (p < 0.05). MPO activities decreased in groups II (p < 0.05) and III (p < 0.05), indicating reduced neutrophil sequestration. W/D ratio was significantly lower in groups II and III. CONCLUSION: Both methods of NP administration are effective, but NP administration in the recipient is accompanied by a decrease in systemic vascular resistance. From a clinical point of view, NP administration in the flush solution is a sufficiently effective and practical method to reduce lung allograft reperfusion injury. PMID- 9361252 TI - Further data about venous channels in South African Plio-Pleistocene hominids. AB - Original data about venous channels in South African Plio-Pleistocene hominids are discussed. To assess possible changes in blood volume flow of fossil hominids, we test whether dimensions of three extracranial venous foramina were different between Australopithecus africanus and Australopithecus (Paranthropus) robustus. Moreover, providing further data about the small sample of South African Plio-Pleistocene hominids, we also attempt to re-analyse the incidence of divided hypoglossal canals and four emissary foramina in a very large sample of extant African apes representing all ages, species and subspecies, in A. africanus and in "robust australopithecines". Up to now, only very poor data on extracranial dimensions of venous foramina were available for fossil hominids. However, this topic provides interesting information about the modifications of volume flow during human evolution. Assuming that in fossil hominids, as in humans, dimensions of condylar and mastoid foramina, as well as those of jugular foramina, depended on volume flow through them, we conclude, first, that volume flow through internal jugular veins was comparable in South African australopithecines, extant chimpanzees and humans, and second, that, in comparison with the extant less-encephalized chimpanzees (presumably reflecting the ancestral condition), volume flow was higher through condylar veins in A. (P.) robustus. This increase was responsible for a significantly greater amount of blood drainage from the brain (and consequently an increased arterial blood supply). We support the view that encephalization was the prevailing functional explanation for volume flow increase through condylar veins in A. (P.) robustus, in comparison with its ancestor with its presumably more ape-like degree of encephalization. Considering the incidence of emissary canals and foramina, significant differences between A. africanus, "robust australopithecines" and all the extant African ape species, were tested statistically. Concerning the condylar canal, we did not find differences between "robust australopithecines" and extant African apes. Concerning the incidence of divided hypoglossal canals, mastoid canals, parietal and occipital foramina, no difference was found between extant African apes, A. africanus and "robust australopithecines". High frequencies of either condylar or mastoid canals cannot be regarded as a "pongid condition". Moreover, we did not find convincing data to support the hypothesis that mastoid emissary veins (partly representing a putative "radiator" for cooling the brain) were selected in A. africanus, in comparison with "robust australopithecines". PMID- 9361253 TI - A revised systematic scheme for the Eurasian Miocene fossil Hominidae. AB - The current systematics of the European hominids has recently been reexamined in light of new and important fossil discoveries. It has been argued by Begun (1992a) that the European dryopithecines (including Graecopithecus from Greece) represent one of the earliest members of the Hominidae. Andrews (1992) and Dean & Delson (1992) agree that Graecopithecus should probably be placed within the Homininae, but that Dryopithecus should be excluded from this subfamily and retained within the Dryopithecinae. De Bonis & Koufos (1993, 1994) suggest that Graecopithecus shares a sister-group relationship with hominins. Moya-Sola & Kohler (1993, 1995), however, argue that Dryopithecus and Graecopithecus both represent primitive members of the Ponginae. A phylogenetic and taxonomic revision of these taxa presented here supports the allocation of Graecopithecus to Homininae. It is also shown that the apparent disagreement concerning Dryopithecus is a result of the presence of two distinct genera within the fossil samples examined. It is concluded that the Hungarian hominid should be retained within the genus Dryopithecus, and the subfamily Dryopithecinae; the Spanish hominids are allocated to the resurrected genus Hispanopithecus Villalta & Crusafont-Pairo, 1944 which is likely to be a primitive member of the Ponginae. PMID- 9361254 TI - Umbrella hypotheses and parsimony in human evolution: a critique of the Aquatic Ape Hypothesis. AB - Conventionally, anthropologists have sought to explain a multitude of unique features of modern humans as the outcome of a single adaptive breakthrough. These "umbrella hypotheses" are aesthetically appealing because they appear to be parsimonious. As internally consistent hypotheses about the past, they are very difficult to prove incorrect in an absolute sense. Anthropology has often rejected them by consensus without developing explicit reasons. This essay explores one example of these models, the Aquatic Ape Hypothesis, the proponents of which continue to argue that they have not received a fair hearing among anthropologists. The hypothesis is troubled by inconsistencies and has not been reconciled with the fossil record. More importantly, its claim to parsimony is false. The numerous "explanations" for individual anatomical traits that it generates constitute premises that are not better founded than competing terrestrial "explanations". The unifying theme of aquatic adaptation is considerably less parsimonious than the assumption that our lineage has always been terrestrial. Finally, the mosaic pattern of hominid evolution demonstrated by the fossil record will not support this or any single cause theory. Most of these criticisms have been previously voiced in one form or another, yet umbrella hypotheses ranging from mainstream science to the paranormal maintain their popularity among students, general audiences, and scholars in neighboring disciplines. One reason for this is that simple answers, however wrong, are easier to communicate and are more readily accepted than the more sound but more complex solutions. Evolutionary science must wrestle with this problem both in its own community and in the education of the public. PMID- 9361255 TI - Flushing the radiator? A reply to Braga & Boesch. PMID- 9361256 TI - The "radiator" bias. A reply to Falk & Gage. PMID- 9361257 TI - Oral bacteria in miocene Sivapithecus. PMID- 9361258 TI - Did a major immunological event shape the evolutionary histories of apes and Old World monkeys? PMID- 9361259 TI - The incidence of dorsal sulci of the scapula in a modern human population from Ensay, Scotland. PMID- 9361261 TI - Introduction to functional anatomy of the pituitary gland and alterations in disease. PMID- 9361260 TI - IRIS explorer software for radial-depth cueing reovirus particles and other macromolecular structures determined by cryoelectron microscopy and image reconstruction. AB - Structures of biological macromolecules determined by transmission cryoelectron microscopy (cryo-TEM) and three-dimensional image reconstruction are often displayed as surface-shaded representations with depth cueing along the viewed direction (Z cueing). Depth cueing to indicate distance from the center of virus particles (radial-depth cueing, or R cueing) has also been used. We have found that a style of R cueing in which color is applied in smooth or discontinuous gradients using the IRIS Explorer software is an informative technique for displaying the structures of virus particles solved by cryo-TEM and image reconstruction. To develop and test these methods, we used existing cryo-TEM reconstructions of mammalian reovirus particles. The newly applied visualization techniques allowed us to discern several new structural features, including sites in the inner capsid through which the viral mRNAs may be extruded after they are synthesized by the reovirus transcriptase complexes. To demonstrate the broad utility of the methods, we also applied them to cryo-TEM reconstructions of human rhinovirus, native and swollen forms of cowpea chlorotic mottle virus, truncated core of pyruvate dehydrogenase complex from Saccharomyces cerevisiae, and flagellar filament of Salmonella typhimurium. We conclude that R cueing with color gradients is a useful tool for displaying virus particles and other macromolecules analyzed by cryo-TEM and image reconstruction. PMID- 9361262 TI - Development and differentiation of pituitary cells. AB - Classically, it was thought that the adenohypophyseal gland originated from the oral ectoderm. Its development has been the object of numerous studies over many years. However, several questions are still raised about its origin, differentiation, and commitment. The adenohypophyseal gland could originate from the anterior ridge of the neural plate. Glandular adenohypophyseal cells are committed very early in embryonic life. Interactions between adenohypophyseal presumptive territory and neighboring tissues can exist very soon, as early as at the open neural stage. The expression of a given phenotype by the committed cells seems to be controlled by a number of differentiation and/or transcription factors. In view of all these studies, performed with the use of different in vivo and in vitro models, classical concepts of the embryology of the adenohypophyseal gland need to be reevaluated. Indeed, many questions remain unanswered concerning the molecular mechanisms of known and unknown factors controlling development of the adenohypophyseal gland. PMID- 9361263 TI - Cytochemical studies of multifunctional gonadotropes. AB - Studies have focused on the roles of the gonadotrope subsets defined by cytochemical and morphological tools. The evidence points to groups of gonadotropes that may be stimulated to mature and secrete to support surge activity. We postulate that these gonadotropes stem from the medium-sized subset. Other gonadotropes may more involved with maintenance functions. Perhaps these come from the larger cell pools. Monohormonal gonadotropes may play unique roles, such as FSH secretion early in estrus. Some may be immature, others may be regulatory and play both paracrine or autocrine roles in the pituitary cell population. We also recognize that one of the limitations of the current-day cytochemical techniques is that it does not define the entire gonadotrope population in any given two-label protocol. Nevertheless, based on past cytochemical studies, assumptions are made about the extent to which the cells express both hormones or behave in a uniform manner. These assumptions have led researchers to focus on one subset of the gonadotrope population. In their attempts to simplify the population to be studied, they may have eliminated important regulatory, secretory, or monohormonal gonadotropes from the pool. The approach is valid, as long as they recognize that they are studying a subset of a complex and dynamic population. PMID- 9361264 TI - Innervation of the mammalian anterior pituitary: a mini review. AB - The mammalian anterior pituitary was not known to be innervated other than by a few autonomic nerve fibers. Recent studies, however, have demonstrated otherwise. A hypothesis of neural-humoral dual regulation of the mammalian anterior pituitary has been postulated based on the following findings: (1) the presence of substantial amounts of nerve fibers in the anterior pituitary of a number of mammalian species; (2) close contact of the nerve fibers with the gland cells, even forming synapses; (3) the nerve fibers originate, as least partly, from the hypothalamus; (4) the nerve fibers respond actively to changes in hormonal levels of the organism; and (5) stimulation of the nerve fibers changes the secretory activities of the gland cells. PMID- 9361265 TI - Folliculo-stellate cells and intercellular communication within the rat anterior pituitary gland. AB - Folliculo-stellate (FS) cell are agranular and arranged around a follicle. They contain the S-100 protein and beta-adrenergic receptors. It has been suggested that they can act as stem cells, since they show mitotic figures, and could transform into granular or chromophilic cells according to the concept of a "cell renewal system." Cell-to-cell interactions among pituitary cells have been described, and recent progress with freeze-fracture electron microscopy has provided novel observations of the cell surface and gap junctions within the rat or teleost fish pituitary gland, or in cultured rat pituitary cells. In adult rats, the anterior pituitary was composed of lobules incompletely separated by a basement membrane. Follicles consisted exclusively of FS cells. Gap junctions were observed only between adjacent FS cells, in rare cases on the tips of their cytoplasmic processes. Thus, the FS cells, connected by gap junctions, made up a dense cellular network throughout the pituitary. Gap and tight junctions were absent on granular cells. Elongated follicles with columnar FS cells were observed in 10-day-old rats and were separated into smaller units. The number of gap junctions rapidly increased with age until 40-45 days of age. Few S-100 protein positive cells were observed on day 10, along the marginal cell layer and near the so-called postero-lateral wing. The frequency of positive cells increased with age and by day 40; numerous cells were observed throughout the anterior lobe. Gap junction number also varied with the stage of the estrous cycle, and frequency; during diestrus, they were half of that during proestrus or estrus. The number of gap junctions increased in late pregnancy and in lactating rats, probably due to changes in estrogen and progesterone. Hormone (LH-RH and testosterone) treated groups of rats showed accelerated development by almost 10 days, compared with controls. In castrated male rats, the ultrastructure of the pituitary remained immature even at 40 days of age, when the number of gap junctions was a quarter or less than the number in intact rats. Testosterone treatment restored the frequency of gap junctions to a normal level. We conclude that the appearance of gap junctions in the pituitary cells and maturation of the gland are dependent to a large degree upon gonadal steroids. PMID- 9361266 TI - Paracrine communication in the anterior pituitary as studied in reaggregate cell cultures. AB - The classical image of the endocrine system is that secretory function of a gland is regulated from outside that gland by other organs. Focused on the pituitary gland, hormone secretion by the anterior lobe is under control of peptides and biogenic amines produced by the hypothalamus. About a decade ago, our group launched the new idea that functioning of the anterior pituitary (AP) is also regulated from within, i.e., that the constituent cell types inter-communicate to control hormone secretion. Extensive in vitro research has now provided a body of evidence that paracrine communication plays an important role, not only in regulation of hormone secretion but also in development, growth, and differentiation of the AP [reviewed in Denef (1994) The Pituitary Gland, pp. 351 378]. It further revealed that crosstalk between the cells is mediated by local, paracrine, factors. The main objective of our research is to identify those factors, their actions and the producing and target cell type(s) in order to unravel the paracrine communication network that is functional in the AP. Equally important, we set the step towards in vivo examination of the results obtained in vitro using transgenic mice. In the present article, we will review the technology used, three examples of AP cell-to-cell interactions studied, and we will discuss the value of transgenic animal models in the study of AP paracrine communication. PMID- 9361267 TI - Application of confocal laser scanning microscopy (CLSM) to visualize prolactin (PRL) and PRL mRNA in the normal and estrogen-treated rat pituitary glands using non-fluorescent probes. AB - In the present study, we performed concomitant visualization of immunohistochemistry (IHC) and in situ hybridization (ISH) on the materials processed for conventional light microscopic specimens using non-fluorescent Confocal Laser. Scanning Microscopy (CLSM). CLSM was used in the reflection confocal mode using horseradish peroxidase (HRP)-3-3'diaminobenzidine (DAB) osmium (osmium black) and nitroblue tetrazolium (NBT) as non-fluorescent detection methods (probes). To obtain clearer images of the organelles, images that were built up as electronic signals in CLSM were processed in an image analysis system (IAS). By using the combination of CLSM and IAS, in IHC, immunohistochemical localization of prolactin (PRL) was in well-developed lamellar or whorling rough endoplasmic reticula (RER), Golgi apparatus, and secretory granules. With ISH, the expression and distribution of PRL messenger ribonucleic acid (mRNA) was observed in a fashion suggesting polysome-like structures on RER. These observations were confirmed by immunoelectron microscopy and electron microscopic ISH. The herein-described method is expected to be useful to perform the concomitant observation of IHC and ISH at subcellular levels using the conventional light microscopic specimens. PMID- 9361268 TI - Transcription factors in normal and neoplastic pituitary tissues. AB - Transcription factors are proteins that bind to regulatory elements in DNA and have critical roles in gene regulation during development, in cellular growth and differentiation. The four major groups of transcription factors have been classified according to the motif in the DNA-binding domains and include: (1) the helix-turn-helix group, which includes the Pit-1/GHF-1 (Pit-1) transcription factor; (2) the zing finger group, which includes estrogen and other steroid hormone receptors; (3) the leucine zipper group, which includes c-fos protooncogene, and (4) the helix-loop-helix group, which includes the c-myc oncogene. Members of all four groups have been described in normal and neoplastic anterior pituitary gland tissues. Pit-1 has been shown to regulate prolactin (PRL), growth hormone (GH), and thyroid-stimulating hormone (TSH) cells during development and differentiation. Genetic defects in this transcription factor have led to specific diseases in rodents and humans such as dwarfism and cretinism. Estrogen receptor (ER) protein plays a critical role in the regulation of gene expression in some anterior pituitary cells. There is a differential distribution of ER in anterior pituitary cells and tumors; PRL, gonadotroph, and null cell tumors are the principal adenomas expressing ER. The protooncogene c fos is regulated by estrogen in various tissues, linking the regulation of one transcription factor by another transcription factor with a different motif. The c-myc oncogene has been detected in the pituitary gland and in some pituitary tumors, although the exact role of this oncogene in pituitary tumor development is uncertain. Because of the critical role that transcription factors play in pituitary cell development and differentiation, we can anticipate many more studies to elucidate their many functions in normal and neoplastic pituitary tissues. PMID- 9361269 TI - Gene expression in pituitary adenomas: new insights. PMID- 9361270 TI - Transgenic models of pituitary diseases. AB - Transgenic mice are valuable experimental models of human endocrine diseases. Targeted ablation of specific cell lineages or insertion of genes coding for releasing factors, hormones, growth factors, and oncogenes fused with appropriate promoters, or mutated genes, can induce several pituitary disorders. Various hyposecretory and hypersecretory states have been induced, some of them due to functioning pituitary adenomas. Adenohypophysial changes in such disorders have been thoroughly investigated in many of the transgenic lines. Functioning and silent pituitary adenomas resemble those seen in human patients, and are invaluable models of tumorigenesis. The available models have not been sufficiently exploited and new models are expected in the near future. In this review, the morphologic changes of the pituitary are described in transgenic mice and, when available, the ultrastructural alterations are included. PMID- 9361271 TI - A coherent nomenclature for Eph receptors and their ligands. PMID- 9361272 TI - Soluble myelin-associated glycoprotein (MAG) found in vivo inhibits axonal regeneration. AB - Myelin-associated glycoprotein (MAG) is a potent inhibitor of axonal regeneration when used as a substrate for growth. However, to be characterized definitively as inhibitory rather than nonpermissive, MAG must also inhibit axonal regeneration when presented in solution. Here, we show that soluble dMAG (extracellular domain only), released in abundance from myelin and found in vivo and chimeric MAG-Fc, can potently inhibit axonal regeneration. For both dMAG and MAG-Fc, inhibition is dose-dependent. If myelin-conditioned medium is immunodepleted of dMAG, or if a MAG antibody is included with MAG-Fc, inhibition is completely neutralized. Together with MAG's ability to induce growth cone collapse, these results demonstrate that MAG is an inhibitory molecule and not merely nonpermissive. The results also suggest that MAG binds to a specific receptor and initiates a signal transduction cascade to effect inhibition. Importantly, these results indicate that soluble dMAG detected in vivo could contribute to the lack of regeneration in the mammalian CNS after injury. PMID- 9361273 TI - Migration of neocortical neurons in the absence of functional NMDA receptors. AB - A variety of factors, from cell adhesion to changes in intracellular calcium, are thought to influence neuronal migration. Here we examine the possibility that calcium influx mediated via NMDA receptors regulates migration of neocortical neurons. We have examined the cytoarchitecture of the cortex in transgenic mice lacking functional NMDA receptors. Using cell birthdating techniques we found that cells in the developing neocortex of NMDAR-1 mutant mice have a distribution indistinguishable from that in animals with functional NMDA receptors, implying normal rates and routes of migration. These observations contrast with previous in vitro pharmacological studies of cerebellar granule cell migration, in which a role for NMDA receptors has been demonstrated. Thus, either different mechanisms are responsible for controlling neuronal migration in neocortex versus cerebellum or, more likely, neocortical neurons in NMDAR-1 mutant mice have acquired compensatory mechanisms for cell migration. PMID- 9361274 TI - Structural features of collapsin required for biological activity and distribution of binding sites in the developing chick. AB - We have used Fc-chimeras of collapsin-1/Sema III to study the structure-function activity of this recently identified repulsive axonal guidance molecule and to map the distribution of its binding sites during chick development. Our results show that the biological activity of the collapsin-Fc in an in vitro collapse assay is independent of both the Ig-domain and the positive charged carboxy terminus. Collapsin binding sites were found on a number of neuronal fiber tracts, and in two instances (DRG tracts and the retinotectal projection) this expression is both highly dynamic and consistent with them playing a role in axonal growth and guidance. Collapsin-1 binding sites were also found on a number of nonneuronal structures that do not produce collapsin-1 mRNA. We postulate that these sites may act to localize or concentrate collapsin-1 released from growing axons and in this way allow for an autocrine axonal guidance mechanism to function during development. PMID- 9361275 TI - LIF is an autocrine factor for sympathetic neurons. AB - Leukemia inhibitory factor (LIF) alters neuronal phenotypes both in vitro and in vivo. Since it can be produced by glia and other nonneural cells, LIF is a candidate target-derived differentiation factor as well as an injury-response factor. We here provide evidence that LIF can be produced by neurons and can act on the neurons that produce it. A reverse transcriptase-polymerase chain reaction assay detects LIF mRNA in rat sympathetic neuron cultures, and in situ hybridization combined with MAP2 immunocytochemistry indicates that most of the cells expressing LIF mRNA are, in fact, neurons. The neuronal lysate as well as the conditioned medium contains proteins that are specifically recognized by anti LIF antibodies, and these antibodies also specifically stain the cultured neurons. In addition, concentrated sympathetic neuron conditioned medium can mimic the effects of LIF, and incubation of high-density sympathetic neuron cultures with anti-LIF antibodies reduces basal expression levels of LIF target genes such as particular neuropeptides, indicating that the endogenously produced cytokine is acting on the neurons under these conditions. Since we show that LIF transcript is expressed in sympathetic and sensory neurons in vivo as well, LIF could act in an autocrine fashion under a variety of physiological conditions. PMID- 9361276 TI - Border controls at the mammalian spinal cord: late-surviving neural crest boundary cap cells at dorsal root entry sites may regulate sensory afferent ingrowth and entry zone morphogenesis. AB - Boundary caps (BCs) form when neural crest cells, migrating ventrally alongside the neural tube, arrest at sites where axons will enter and exit. However, nothing is known of their subsequent fate and functions. We have found late surviving neural crest BC cell clusters at proximal dorsal root entry sites throughout rat spinal cord development. Sensory afferents cross BCs to enter the spinal cord, while exiting astrocyte processes, destined to form the dorsal root entry zone (DREZ) after birth, are temporarily stalled in their vicinity. To test whether contact with BC cells influences neurite outgrowth from dorsal root ganglia, neurons were cultured on embryonic dorsal root/spinal cord cryosections. Neurites that entered CNS territory preferentially extended over BC cells. Thus, BC cells could be instrumental in regulating afferent ingrowth and DREZ morphogenesis in mammalian spinal cord development. PMID- 9361277 TI - Reduced size of retinal ganglion cell axons and hypomyelination in mice lacking brain-derived neurotrophic factor. AB - While brain-derived neurotrophic factor (BDNF) delays the death of axotomized retinal ganglion cells in rodents, it is unclear if it affects any aspect of the normal development of these cells. Here we examined the optic nerve of bdnf-/- mice. Axonal numbers were normal, but their diameter, as well as the proportion of myelinated axons, was reduced at postnatal day 20 (P20). In contrast, the facial nerve was not hypomyelinated. Expression levels of mRNAs coding for the myelin proteins PLP and MBP were substantially reduced in the hippocampus and cortex at P20, but not in the sciatic nerve. Intraventricular injections of BDNF into the ventricles of wild-type mice at P10 and P12 up-regulated expression of PLP in the hippocampus at P14. These results indicate a role of BDNF, discussed as indirect, in the control of myelination in the central nervous system. PMID- 9361278 TI - A novel transmembrane semaphorin can bind c-src. AB - The semaphorins/collapsins constitute a family of genes unified by the presence of a "semaphorin domain" which has been conserved through metazoan evolution. The semaphorin family comprises both secreted and transmembrane molecules and is thought to be made up of ligands for as yet unidentified receptors. The functions are not known, with the exception of those of sema III (also referred as sem D and collapsin 1), D-sema I, and D-sema II, which have been shown to be involved in axonal pathfinding. Here report the identification of a mouse semaphorin cDNA, termed Sema VIb. Although Sema VIb contains the extracellular semaphorin domain, it lacks the immunoglobulin domain or thrombospondin repeats which are present in other described vertebrate (but not invertebrate) transmembrane semaphorins. During development Sema VIb mRNA is expressed in subregions of the nervous system and is particularly prominent in muscle. In adulthood, Sema VIb mRNA is expressed ubiquitously. The cytoplasmic domain of Sema VIb contains several proline-rich potential SH3 domain binding sites. Using an in vitro binding assay, we show that Sema VIb binds specifically the SH3 domain of the protooncogene c-src. In transfected COS cells Sema VIb coimmunoprecipitates with c-src. These results, along with our evidence that Sema VIb can form dimers, suggests that the semaphorin family not only serves as ligands but may include members, especially those which are transmembrane, which serve as receptors, triggering intracellular signaling via an src-related cascade. PMID- 9361279 TI - Effects of thyroid hormone on embryonic oligodendrocyte precursor cell development in vivo and in vitro. AB - The oligodendrocyte precursor cell divides a limited number of times before terminal differentiation. The timing of differentiation depends on both intracellular mechanisms and extracellular signals, including mitogens that stimulate proliferation and signals such as thyroid hormone (TH) and retinoic acid (RA) that help trigger the cells to stop dividing and differentiate. We show here that, both in vivo and in vitro, TH is required for the normal development of rodent optic nerve oligodendrocytes, although in its absence some oligodendrocyte development still occurs, perhaps promoted by signals from axons. We also demonstrate that TH from both mother and pup plays a part in oligodendrocyte development in vivo. Finally, we show that precursors in embryonic nerve cultures differ from those in postnatal cultures in two ways: they respond much better to TH than to RA, and they respond more slowly to TH, suggesting that oligodendrocyte precursor cells mature during their early development. PMID- 9361280 TI - Neuronal circuits are subdivided by differential expression of type-II classic cadherins in postnatal mouse brains. AB - A number of type-II classic cadherin cell-cell adhesion molecules are expressed in the brain. To investigate their roles in brain morphogenesis, we selected three type-II cadherins, cadherin-6 (cad6), -8 (cad8) and -11 (cad11), and mapped their expressions in the forebrain and other restricted regions of postnatal mouse brains. In the cerebral cortex, each cortical area previously defined was delineated by a specific combinatorial expression of these cadherins. The thalamus and other subcortical regions of the forebrain were also subdivided by differential expression of the three cadherins; e.g., the medial geniculate body expressed only cad6; the ventral posterior thalamic nucleus, cad6/cad11; and the anteroventral thalamic nucleus, cad6/cad8. Likewise, in the olivocerebellar system, each subdivision of the inferior olive expressed a unique set of the three cadherins, and the cerebellar cortex had parasagittal stripes of cad8/cad11 expressions. Close analysis of these cadherin expression patterns revealed that they are correlated with neuronal connection patterns. Examples of these correlations include that cad6 delineates the auditory projection system, cad6/cad8/ cad11 are expressed by part of the Papez circuit, and cad6/cad8 are expressed by subdivisions of the olivo-nuclear circuit. Together with the recent finding that the cadherin adhesion system is localized in synaptic junctions, our findings support the notion that cadherin-mediated cell-cell adhesion plays a role in selective interneuronal connections during neural network formation. PMID- 9361281 TI - Segregation of rhombomeres by differential chemoaffinity. AB - The developing hindbrain is transiently subdivided into structural repeat units, rhombomeres, whose formation is matched by both differential regulatory gene expression and a metameric pattern of early neuronal differentiation and axogenesis. Individual rhombomeres are polyclonal cell lineage restriction units; once defined by transverse interrhombomere interfaces, cells are confined within the territory of a single rhombomere. In order to assess the relevance of this restriction to hindbrain development. It is necessary to understand the underlying mechanism. One possibility is that cells of adjacent rhombomeres acquire differential affinities or adhesive properties. To explore this possibility, we isolated rhombomere cells, mixed them together in short-term aggregation cultures, and assessed the composition of the resulting aggregates. We found that rhombomeres do differ in their affinity: cells from even-numbered rhombomeres sort out from cells of odd-numbered rhombomeres. They also segregate from cells of other even-numbered rhombomeres but to a much lesser extent. This selective cell affinity operates from the time of rhombomere formation until late stages in development. The region-specific segregation was abolished when Ca(2+) dependent adhesion molecules were inactivated but not when Ca(2+)-independent adhesion molecules were inactivated. These findings suggest that distinct cell affinity restricts cell mixing between adjacent rhombomeres and may be involved in establishing the series of discrete compartments, thereby maintaining anteroposterior positional information during hindbrain development. These results support a general role for cell adhesion molecules in subdividing CNS territories. PMID- 9361283 TI - Neurites, synapses, and cadherins reconciled. PMID- 9361282 TI - SHARPs: mammalian enhancer-of-split- and hairy-related proteins coupled to neuronal stimulation. AB - In the mammalian central nervous system, a diverse group of basic helix-loop helix (bHLH) proteins is involved in the determination of progenitor cells and, subsequently, in regulating neuronal differentiation. Here we report the identification of a novel subfamily of bHLH proteins, defined by two mammalian enhancer-of-split- and hairy-related proteins, termed SHARP-1 and SHARP-2. In contrast to known bHLH genes, detectable transcription of SHARP genes begins at the end of embryonic development marking differentiated neurons that have reached a final position, and increases as postnatal development proceeds. In the adult, SHARP genes are expressed in subregions of the CNS that have been associated with adult plasticity. In PC12 cells, a model system to study neurite outgrowth, SHARP genes can be induced by NGF with the kinetics of an immediate-early gene. Similarly, within 1 h after the administration of kainic acid in vivo, SHARP-2 is induced in neurons throughout the rat cerebral cortex. This suggests that neuronal bHLH proteins are also involved in the "adaptive" changes of mature CNS neurons which are coupled to glutamatergic stimulation. PMID- 9361284 TI - Beta 2 laminins modulate neuronal phenotype in the rat retina. AB - The production of cell types in the vertebrate retina follows a stereotyped time course. We have focused on a component of the extracellular matrix that may guide this schedule: the laminin beta 2 chain. Here, we have asked directly whether heterotrimeric laminins containing the laminin beta 2 chain can promote the production of presumptive rod photoreceptors ("rods") and have correlated changes in rod production with changes in the production of other cell types. In cultures in which few rods, but many Muller and bipolar cells, are produced, the production of rods can be enhanced sixfold and that of bipolar cells can be reduced by 66%, by exposing cells to a laminin beta 2-rich matrix. Substitution of a laminin beta 2-depleted matrix (created with antisense RNA) returns the density of rods and bipolar cells to control levels. These linked alterations in phenotype expression suggest that laminins may control the choice between rod photoreceptor and rod bipolar cell fates. PMID- 9361285 TI - Rapsyn and agrin slow the metabolic degradation of the acetylcholine receptor. AB - Rapsyn is a 43-kDa cytoplasmic protein that clusters nicotinic acetylcholine receptors (AChR) in the postsynaptic membrane. Here we examine the effect of rapsynmediated AChR clustering on the metabolic stability of the AChR. When transfected into QT-6 fibroblasts, cell surface AChRs (alpha, beta, epsilon, and delta subunit combination) pulse labeled with 125I-alpha-bungarotoxin were degraded with a half-life of 16.4 +/- 1.1 h (mean +/- SEM). Cotransfection of rapsyn with AChR caused extensive AChR clustering and increased AChR half-life to 20.5 +/- 1.0 h. Anti-AChR antibodies such as mab 35 cause an increased AChR degradation often associated with myasthenia gravis: 80.8 +/- 2.5% of AChRs labeled at zero time were degraded over a 12-h period. Contransfection of rapsyn reduced this AChR loss to 66.4 +/- 3.8%. Rapsyn also reduced normal AChR degradation, from 53.2 +/- 2.1 to 44.2 +/- 2.2%. Muscle cell lines from wild-type myotubes displayed few AChR clusters, but treatment with neural agrin increased the number of AChR clusters 30-fold. Clustering was accompanied by reductions in AChR degradation (both in the presence and absence of mab 35) similar in magnitude to those produced by overexpression of rapsyn in QT-6 cells. In rapsyn deficient myotubes, treatment with neural agrin neither caused AChR clustering nor reduced AChR degradation. Thus neural agrin may slow AChR degradation by inducing the rapsyn-dependent clustering of AChRs. PMID- 9361286 TI - Proteoglycans provide neurite guidance at an astrocyte boundary. AB - Astrocytes in the developing brain direct neurites through their synthesis of cell surface and extracellular matrix molecules. We introduce a novel culture system to identify and examine the guidance properties of astrocyte-derived molecules. The permissive A7 and nonpermissive Neu7 cell lines were co-cultured to form an A7/Neu7 monolayer. Neurites extended on A7 cells but avoided Neu7 cells and instead stopped or turned at the A7/Neu7 Interface. Enzymatic treatment with trypsin and hyaluronic acid increased neurite extension, but neither altered the boundary. Only, removal of keratan and chondroitin sulfate residues reduced the guidance capacity of the A7/Neu7 boundary. Since no treatment individually abolished the boundary, neurite guidance appears to be due to a combination of factors. The A7/Neu7 astrocyte substrate demonstrates the functional role for KSPGs and CSPGs, but more interestingly, suggests that simply increasing the capacity of a substrate to permit neurite outgrowth does not necessarily eliminate or even reduce its guidance properties. PMID- 9361287 TI - Limbic system-associated membrane protein (LAMP) induces neurite outgrowth and intracellular Ca2+ increase in primary fetal neurons. AB - The ability of cell adhesion molecules (CAMs) to transduce cell surface signals into intracellular responses is critical for developing neurons, particularly during axonal pathfinding and targeting. It has been suggested that different CAMs can promote neuronal outgrowth via activation of common neuronal CAM specific second-messenger pathways, although the elements involved in this cascade could differ. Limbic system-associated membrane protein (LAMP), a member of the Ig superfamily, is a molecule that promotes cell adhesion and neurite outgrowth from specific populations of fetal neurons. In the present study, we show that LAMP can induce several types of calcium (Ca2+) signals. Neurite outgrowth is promoted if fetal hippocampal neurons are grown on lamp-transfected CHO cells. This LAMP-induced outgrowth of neurons is mediated in part through activation of L-type Ca channels. Application of soluble LAMP to cultures of fetal hippocampal neurons caused a sustained (up to 60 min) elevation of intracellular Ca2+ as measured by fluo-3 fluorescence on a confocal microscope. The number of responding hippocampal neurons was initially low, but increased with age in culture and the [Ca2+]i elevation was only partially decreased by an L-type Ca(2+)-channel blocker. In contrast, at all times in culture, only a small fraction of neurons from visual cortex responded to LAMP application and only with transient elevation of cytosolic Ca2+ (< 15 min). Based on these observations, LAMP appears to function primarily through homophilic interactions and acts in part by modulating intracellular Ca2+ levels during neurite outgrowth by increasing the Ca2+ influx through L-type calcium channels, but has additional effects on intracellular Ca2+ signaling at later developmental stages. PMID- 9361288 TI - A role of midkine in the development of the neuromuscular junction. AB - Midkine (MK) is a member of a family of developmentally regulated neurotrophic and heparin-binding growth factors. It is expressed during the midgestation period in a retinoid-acid dependent manner during embryogenesis in the mouse. In vitro, it promotes neurite outgrowth from spinal cord neurons and cell migration. It expression is strongest in the central nervous system, thus suggesting a function for this protein in neural development. In this study, the role of MK in synaptogenesis was examined in the Xenopus system. A Xenopus MK cDNA was cloned from an embryonic library encompassing neurulation and synaptogenesis stages. By Northern blot analysis, MK mRNA was detected from the onset of neurulation and throughout the stages of synaptogenesis in the Xenopus embryo. This suggests that MK is also an important growth regulator in Xenopus embryogenesis. To study the function of MK in the development of the neuromuscular junction (NMJ), fusion proteins were made and their ability to induce the formation of acetylcholine receptor (AChR) clusters in cultured muscle cells was studied. Beads coated with MK strongly induce AChR clustering. When nerve-muscle cocultures were labeled with antibodies made against the MK fusion protein, MK immunoreactivity was detected at the NMJ. Unlike heparin-binding growth-associated molecule (HB-GAM), another member of this growth factor family, MK expression cannot be detected in the muscle but is present in spinal cord neurites. Consistent with these in vitro data is the observation that MK mRNA is only localized in the central nervous system but the protein is deposited at the intersomitic junction where the NMJ is located in vivo. Exogenously applied MK does bind to the heparan sulfate proteoglycan on the surface of Xenopus muscle cells. Agrin, a heparan-sulfate proteoglycan that induces the formation of AChR clusters in cultured muscle cells, binds strongly to MK. Bath application of MK in conjunction with agrin results in a change in the pattern of AChR clustering induced by agrin alone. These data suggest that MK is a neuron-derived factor that participates in the signal transduction process during NMJ development. PMID- 9361289 TI - Molecular cloning of a new intermediate filament protein expressed by radial glia and demonstration of alternative splicing in a novel heptad repeat region located in the carboxy-terminal tail domain. AB - In the present study we describe the molecular cloning of transitin, formerly named EAP-300. We show that transitin is an intermediate filament protein with a core domain most closely resembling nestin and tanabin. Transitin also contains a novel heptad amino acid repeat domain, comprising multiple leucine zipper repeats, located in its tail region. Based on these structural motifs we propose that a novel intermediate filament protein that is transiently expressed by radial glia during CNS development has been identified. We also show the existence of splice variants of transitin with splicing occurring in the novel heptad repeat domain to give rise to transitin isoforms that lack this heptad repeat. By in situ hybridization analysis we show that transitin mRNA is expressed by midline radial glial structures, by several axon commissures, and by Bergmann glia of the developing cerebelium. Based on the structural properties of the transitin protein, and expression of its mRNA, we suggest that transitin is a new member of the intermediate filament gene superfamily that is transiently expressed by radial glia. PMID- 9361290 TI - Antisense agrin cDNA transfection blocks neuroblastoma cell-induced acetylcholine receptor aggregation when co-cultured with myotubes. AB - A neuroblastoma x glioma hybrid cell line, NG108-15, was able to induce the aggregation of AChRs when co-cultured with myotubes. NG108-15 cells in culture expressed agrin, producing a protein of approximately 220 kDa and a transcript of approximately 8.0 kb. The mRNA encoding the agrin isoform having no amino acid insertion at either the Y or the Z site, namely agrin0.0, was the only transcript detected in NG108-15 cells when they were cultured alone or co-cultured with myotubes. NG108-15 cells could be induced to differentiate by chemical treatment, and the chemical-induced differentiation of NG108-15 cells increased the level of agrin mRNA expression approximately fourfold while the expression of a housekeeping gene remained relatively unchanged. The increase in agrin expression of differentiated NG108-15 cells paralleled the increase in AChR-aggregating activity of differentiated NG108-15 cells, indicating that the agrin derived from NG108-15 cells could be the receptor-aggregating factor. In addition, we created a stable clonal NG108-15 cell line that was transfected with antisense agrin cDNA and its expression of agrin was abolished, while its AChR-aggregating activity was completely lost when co-cultured with myotubes. This is the first direct demonstration that NG108-15 cell-induced AChR aggregation on cultured myotubes is mediated by neuron-derived agrin. PMID- 9361291 TI - Long and short splice variants of human tenascin differentially regulate neurite outgrowth. AB - Tenascin-C has been implicated in regulation of neurite outgrowth both during development and after injury; however, its role as permissive vs inhibitory remains controversial. We report that different tenascin splice variants may have dramatically different impacts on neuronal growth. In a cell culture model, the largest and smallest splice variants (TN.L and TN.S) of human tenascin both promoted process extension when surface-bound. In contrast, soluble TN.S inhibited outgrowth, whereas soluble TN.L had no inhibitory effect. Perturbation experiments with antibodies, and outgrowth experiments with recombinant tenascin fragments, indicate that the differential properties of these molecules can be attributed to their distinctive array of FN-III repeats. Monoclonal antibodies were used to demonstrate at least two distinct neurite outgrowth promoting domains within the alternatively spliced region. These results suggest that the effect of tenascin on axon growth is a function of splice variants, as well as the form or conformation of those variants. PMID- 9361292 TI - Monoclonal antibody interaction with the third immunoglobulin-like domain of N CAM is sufficient to cause cell migration. AB - Cellular adhesion molecules can influence a variety of biological mechanisms in the nervous system. These range from the processes of normal development and maintenance to neural plasticity and recovery following injury. The elucidation of the intricate contributions of these molecules will require the correlation of functional assays with specific molecules and the specific binding domains of such molecules with multiple signaling pathways. The data presented in this paper show that the monoclonal antibody anti-NCAM16, directed against the third immunoglobulin-like domain of the neural cell adhesion molecule N-CAM, is capable of stimulating the complex biological process of cell migration in primary embryonic motor neurons and human neuronal cell lines. PMID- 9361293 TI - Zinc metabolism in the brain: relevance to human neurodegenerative disorders. AB - Zinc is an important trace element in biology. An important pool of zinc in the brain is the one present in synaptic vesicles in a subgroup of glutamatergic neurons. In this form it can be released by electrical stimulation and may serve to modulate responses at receptors for a number of different neurotransmitters. These include both excitatory and inhibitory receptors, particularly the NMDA and GABA(A) receptors. This pool of zinc is the only form of zinc readily stained histochemically (the chelatable zinc pool), but constitutes only about 8% of the total zinc content in the brain. The remainder of the zinc is more or less tightly bound to proteins where it acts either as a component of the catalytic site of enzymes or in a structural capacity. The metabolism of zinc in the brain is regulated by a number of transport proteins, some of which have been recently characterized by gene cloning techniques. The intracellular concentration may be mediated both by efflux from the cell by the zinc transporter ZrT1 and by complexing with apothionein to form metallothlonein. Metallothionein may serve as the source of zinc for incorporation into proteins, including a number of DNA transcription factors. However, zinc is readily released from metallothionein by disulfides, increasing concentrations of which are formed under oxidative stress. Metallothionein is a very good scavenger of free radicals, and zinc itself can also reduce oxidative stress by binding to thiol groups, decreasing their oxidation. Zinc is also a very potent inhibitor of nitric oxide synthase. Increased levels of chelatable zinc have been shown to be present in cell cultures of immune cells undergoing apoptosis. This is very reminiscent of the zinc staining of neuronal perikarya dying after an episode of ischemia or seizure activity. Thus a possible role of zinc in causing neuronal death in the brain needs to be fully investigated. intraventricular injections of calcium EDTA have already been shown to reduce neuronal death after a period of ischemia. Pharmacological doses of zinc cause neuronal death, and some estimates indicate that extracellular concentrations of zinc could reach neurotoxic levels under pathological conditions. Zinc is released in high concentrations from the hippocampus during seizures. Unfortunately, there are contrasting observations as to whether this zinc serves to potentiate or decrease seizure activity. Zinc may have an additional role in causing death in at least some neurons damaged by seizure activity and be involved in the sprouting phenomenon which may give rise to recurrent seizure propagation in the hippocampus. In Alzheimer's disease, zinc has been shown to aggregate beta-amyloid, a form which is potentially neurotoxic. The zinc-dependent transcription factors NF-kappa B and Sp1 bind to the promoter region of the amyloid precursor protein (APP) gene. Zinc also inhibits enzymes which degrade APP to nonamyloidogenic peptides and which degrade the soluble form of beta-amyloid. The changes in zinc metabolism which occur during oxidative stress may be important in neurological diseases where oxidative stress is implicated, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS). Zinc is a structural component of superoxide dismutase 1, mutations in which give rise to one form of familiar ALS. After HIV infection, zinc deficiency is found which may be secondary to immune-induced cytokine synthesis. Zinc is involved in the replication of the HIV virus at a number of sites. These observations should stimulate further research into the role of zinc in neuropathology. PMID- 9361294 TI - Apolipoprotein E, a gene with complex biological interactions in the aging brain. AB - Age-dependent neurodegeneration in Alzheimer disease (AD) may be viewed as a complex interaction among: (i) susceptibility polymorphisms, (ii) somatic mutations or alterations that occur over extended periods of time, and (iii) environmental interactions. Putative "sporadic" diseases appear to have a much stronger genetic component than had been considered previously. For example, in Alzheimer disease, apolipoprotein E is a major susceptibility locus that accounts for approximately half the heritability. Specific APOE genotypes are associated with different relative risks and age of onset distributions. Disease may be expressed as a confluence of several genetic risk factors, superimposed upon the age-dependent increments of somatic mitochondrial mutations, and environmental determinants such as head injury, stroke, or hypoxia. A matrix involving each of these complex factors may influence the age of onset of AD in a particular individual. With careful clinically based family and epidemiological studies, it is now possible to tease out the relevant genetic contributions from the confluence of other factors leading to complex disease affecting specific sets of neurons. The highly intricate maze of contributing factors provides many potential unanticipated opportunities to design rational therapeutic and preventative strategies. PMID- 9361295 TI - Studies on neuroprotective and regenerative effects of GDNF in a partial lesion model of Parkinson's disease. AB - Intrastriatal 6-hydroxydopamine injections in rats induce partial lesions of the nigrostriatal dopamine (DA) system which are accompanied by a delayed and protracted degeneration of DA neurons within the substantia nigra. By careful selection of the dose and placement of the toxin it is possible to obtain reproducible and regionally defined partial lesions which are well correlated with stable functional deficits, not only in drug-induced behaviors but also in spontaneous motoric and sensorimotoric function, which are analogous to the symptoms seen in patients during early stages of Parkinson's disease. The intrastriatal partial lesion model has proved to be particularly useful for studies on the mechanisms of action of neurotrophic factors since it offers opportunities to investigate both protection of degenerating DA neurons during the acute phases after the lesion and stimulation of regeneration and functional recovery during the chronic phase of the postlesion period when a subset of the spared nigral DA neurons persist in an atrophic and dysfunctional state. In the in vivo experiments performed in this model glial cell line-derived neurotrophic factor (GDNF) has been shown to exert neurotrophic effects both at the level of the cell bodies in the substantia nigra and at the level of the axon terminals in the striatum. Intrastriatal administration of GDNF appears to be a particularly effective site for induction of axonal sprouting and regeneration accompanied by recovery of spontaneous sensorimotor behaviors in the chronically lesioned nigrostriatal dopamine system. PMID- 9361296 TI - Insulin-like growth factors regulate neuronal differentiation and survival. AB - Insulin-like growth factor I (IGF-I) and IGF-II are potent trophic factors for motor and sensory neurons and glial cells. The actions of IGF-I and IGF-II are mediated via the IGF-I receptor (IGF-IR). IGF:IGF-IR binding activates distinct signaling cascades, which in turn mediate the trophic effects of the IGFs. We discuss three main IGF coupled events: growth cone motility, long-term neurite outgrowth, and neuroprotection. Our data suggest that IGF-I enhances growth cone motility by promoting reorganization of actin and activation of focal adhesion proteins via the phosphatidylinositol-3 kinase (Pl-3K) pathway. Long-term treatment with IGF-I activates the mitogen-activated protein (MAP) kinase cascade and promotes neurite outgrowth. A separable, but likely linked, action of the IGFs via Pl-3K is protection of neurons from apoptosis. These pleotrophic effects of IGFs suggest that this family of growth factors may have potential clinical utility in the treatment of neurological disorders. PMID- 9361297 TI - Advances in Charcot-Marie-Tooth disease research: cellular function of CMT related proteins, transgenic animal models, and pathomechanisms. The European CMT Consortium. AB - The First Workshop of the European Consortium on Charcot-Marie-Tooth (CMT) disease brought together neuroscientists, molecular and cell biologists, neuropathologists, neurologists, and geneticists with a common interest in the understanding of the fundamental mechanisms that underlie the pathogenesis of CMT. The interdisciplinary group of 25 expert scientists discussed recent advances in (i) molecular genetics and histopathology of CMT, (ii) development of suitable animal models, (iii) understanding of the cellular function of CMT related proteins, and (iv) studies using nerve biopsies from CMT patients. In this minireview, we summarize the key findings presented and discuss their impact on CMT research. PMID- 9361298 TI - Connexin32 and X-linked Charcot-Marie-Tooth disease. AB - Mutations in the gap junction gene connexin32 (Cx32) cause the X-linked form of Charcot-Marie-Tooth disease, an inherited demyelinating neuropathy. More than 130 different mutations have been described, affecting all portions of the Cx32 protein. In transfected cells, the mutant Cx32 proteins encoded by some Cx32 mutations fall to reach the cell surface; other mutant proteins reach the cell surface, but only one of these forms functional gap junctions. In peripheral nerve, Cx32 is localized to incisures and paranodes, regions of noncompact myelin within the myelin sheath. This localization suggests that Cx32 forms "reflexive" gap junctions that allow ions and small molecules to diffuse directly across the myelin sheath, which is a thousandfold shorter distance than the circumferential pathway through the Schwann cell cytoplasm. Cx32 mutations may interrupt this shorter pathway or have other toxic effects, thereby injuring myelinating Schwann cells and their axons. PMID- 9361299 TI - The nagging question of the function of N-acetylaspartylglutamate. AB - N-Acetylaspartylglutamate (NAAG) is a neuropeptide found in millimolar concentrations in brain that is localized to subpopulations of glutamatergic, cholinergic, GABAergic, and noradrenergic neuronal systems. NAAG is released upon depolarization by a Ca(2+)-dependent process and is an agonist at mGluR3 receptors and an antagonist at NMDA receptors. NAAG is catabolized to N acetylaspartate and glutamate primarily by glutamate carboxypeptidase II, which is expressed on the extracellular surface of astrocytes. The levels of NAAG and the activity of carboxypeptidase II are altered in a regionally specific fashion in several neuropsychiatric disorders. PMID- 9361300 TI - Molecular adaptations to psychostimulants in striatal neurons: toward a pathophysiology of addiction. PMID- 9361301 TI - Do compensatory processes underlie the preclinical phase of neurodegenerative disease? Insights from an animal model of parkinsonism. AB - Lesions of the DA neurons innervating the striatum is accompanied by permanent gross neurological deficits only when the loss of striatal DA is almost complete, a finding reminiscent of Parkinson's disease. This appears to result at least in part from an enhanced capacity of the remaining DA neurons to continue to modulate DA-sensitive targets in the striatum. Among the neurochemical changes that may be responsible for this enhanced capacity are a loss of high-affinity DA uptake sites and time-dependent increases in the synthesis and release of DA. Following very large lesions, an increase in the sensitivity of striatal cells to DA also gradually occurs (Fig. 1). A lesion-induced increase in the functional activity of residual neurons may be a rather general phenomenon. We have made analogous observations in the sympathoadrenal system (Fluharty et al., 1985) and in the noradrenergic (Acheson & Zigmond, 1981; Chiodo et al., 1983; Abercrombie et al., 1989) and serotonergic (Stachowiak et al., 1986) systems of CNS. Thus, during many neurodegenerative diseases, compensatory changes in the affected neural system and its targets may be involved in the extended preclinical stage that often is observed. This hypothesis has several implications. First, many clinical disorders that appear late in life may in fact have their origins in events that had occurred many years earlier, and the emergence of neurological or psychiatric symptoms may represent the end stage of the neurodegenerative process, rather than its onset. Second, to reverse clinical symptoms one may not need to reverse the entire neurobiological deficit; instead, clinical recovery might be achieved with a relatively modest restoration of the injured projections. Third, it may be possible to achieve recovery even without restoring the connections that have been lost if the capacity of the remaining elements of the injured system can be enhanced further. Finally, in some cases arresting the degenerative process may be sufficient; the natural compensatory processes of the nervous system might then be permitted the time needed to restore function. PMID- 9361302 TI - Ion channel mutations and diseases of skeletal muscle. AB - Voltage-gated ion channels play a critical role in coupling excitation at the neuromuscular junction to activation of contractile elements within a muscle fiber. Abnormal channel function can lead to either muscle paralysis or delayed relaxation. Recent advances in the molecular characterization of these ion channels have provided the tools needed to investigate the relationship between channel mutations and disorders of muscle excitability. This article reviews our current understanding of muscle sodium, calcium, and chloride channels and their role in the pathogenesis of myotonia and periodic paralysis. PMID- 9361303 TI - Simian immunodeficiency virus: a model for neuroAIDS. AB - In addition to its profound effects on the immune system, HIV also infects the CNS and can cause abnormalities in infected individuals ranging from mild cognitive and motor disorders to frank dementia. We have been actively investigating the molecular and cellular mechanisms underlying the CNS manifestations of lentivirus infection through the comparative evaluation of brain pathophysiology under a number of parallel interrelated strategies. Here we describe our ongoing studies with the SIV/rhesus macaque system. We have applied an interdisciplinary multistep approach, utilizing viral, immunological, pathological, behavioral, and electrophysiological techniques to assess disease and study CNS dysfunction induced by SIV. The profile of the infection and the host response, and the resulting cognitive, motor, and neurophysiological abnormalities in SIV-infected monkeys, recapitulates many aspects of the functional impairments associated with HIV-induced CNS disease in humans. Consequently, the SIV model is ideal for examining the mechanisms underlying these functional abnormalities and for testing potential therapeutic agents. PMID- 9361304 TI - Measurement of intracellular free zinc in living neurons. AB - Excessive Zn2+ influx has been implicated in the pathogenesis of neuronal death after global ischemia or prolonged seizures, but little is presently known about cellular regulation of intracellular free Zn2+ ([Zn2+]i). In large part, this is because the tools currently available for measuring [Zn2+]i are limited in comparison to those available for measuring [Ca2+]i or other ions. We outline here approaches to this task that have been taken in the past, and summarize our recent experience using mag-fura-5 to measure [Zn2+]i in living cortical neurons exposed to toxic levels of extracellular Zn2+. PMID- 9361305 TI - In vivo adenovirus-mediated gene transfer for Parkinson's disease. AB - Gene therapy is a potentially powerful approach to the treatment of neurological diseases. Neurotransmitter synthesizing enzymes and neurotrophic factors inhibiting neurodegenerative processes provide the basis for current development of gene therapy strategies for Parkinson's disease. Recently, in vivo gene transfer to the brain has been developed using adenovirus vectors. One of the advantages of recombinant adenovirus is that it can transduce both quiescent and actively dividing cells, thereby allowing both direct in vivo gene transfer and ex vivo gene transfer to neural cells. The expression of adenoviral vectors persists for several months with little inflammation, probably because the brain is partially protected from the immune system. Recombinant adenoviruses are currently being improved, particularly by inactivating viral genes controlling the expression of immunodominant viral proteins. Novel therapeutic tools such as vectors for gene therapy have to be evaluated in terms of efficacy and safety for future clinical trials. These vectors still need to be improved to allow long term and possibly regulatable expression of the transgene. PMID- 9361306 TI - The immunosuppressant drug FK506 ameliorates secondary mitochondrial dysfunction following transient focal cerebral ischemia in the rat. AB - Recirculation following 2 h of focal ischemia due to transient middle cerebral artery (MCA) occlusion has previously been found to be accompanied by an initial, partial recovery of the cellular bioenergetic state and of mitochondrial respiratory functions, with secondary deterioration during the first 2-4 h of reflow. Both the free radical spin trap alpha-phenyl-N-tert-butyl nitrone (PBN) and the immunosuppressant drug FK506 ameliorate the damage incurred by the 2-h period of focal ischemia, even when given 1-3 h after the start of the recirculation. The primary objective of this study was to find out if FK506, like PBN, prevents the secondary deterioration of mitochondrial function, as this can be studied in vitro. Since this proved to be the case, we addressed the question of whether the secondary mitochondrial dysfunction and bioenergetic failure were related to a secondary compromise of microcirculation and cellular oxygen delivery. Six groups of male Wistar rats were studied for measurement of mitochondrial respiratory activity (total, n = 36). One group was used as control (n = 6). In the other groups of animals, MCA occlusion of 2 h duration was induced by an intraluminal filament technique, Neocortical focal and perifocal ("penumbra") tissues were sampled after 2 h of ischemia (n = 6) and after 1 h (n = 6), 2 h (n = 6 with vehicle), and 4 h (n = 6 with vehicle; n = 6 with FK506) of recirculation. The vehicle or 1.0 mg.kg-1 of FK506 was injected intravenously after 1 h of recirculation. Homogenates were prepared, and stimulated (+ADP), nonstimulated (-ADP), and uncoupled respiratory rates were measured polarographically. The uncoupling agent used was carbonyl cyanide m chlorophenylhydrazone. Local CBF and tissue oxygen tension were evaluated by laser-Doppler flowmetry and PO2 microelectrodes, respectively, throughout the whole periods of 2 h of ischemia and 4 h of recirculation, using a remote MCA occlusion technique. After 2 h of ischemia, the penumbra showed a moderate decrease and the focus a marked decrease in ADP-stimulated and uncoupled respiratory rates, with a marked fall in the respiratory control ratio, defined as ADP-stimulated divided by nonstimulated respiration. Recirculation (1 h) brought about partial recovery, but continued reflow (2 and 4 h) was associated with a secondary deterioration of respiratory functions. The secondary deterioration was prevented by FK506. The results thus confirm previous findings showing that secondary mitochondrial dysfunction occurs following transient focal cerebral ischemia and demonstrate that FK506, like PBN, improves the in vitro performance of mitochondria in focal and penumbral areas. Following MCA occlusion, local CBF in a penumbral area and tissue PO2 in a focal area decreased to about 30 and 5% of control, respectively. However, recirculation brought about rapid recovery of blood flow and oxygen delivery. During the whole 4-h period of recirculation, local CBF and tissue PO2 were maintained close to 100% and at about 160% of the preischemic level, respectively. The results make it highly unlikely that the secondary bioenergetic failure during recirculation is due to a compromised microcirculation. It follows that oxygen delivery is not rate limiting for recovery events. Very likely, FK506 (and PBN) acts at the cellular level to improve mitochondrial energy functions. PMID- 9361307 TI - HIV-I induced destruction of neocortical extracellular matrix components in AIDS victims. AB - Neurological dysfunction is not uncommon in patients suffering from acquired immunodeficiency syndrome (AIDS) and, when manifested, intimates involvement of the central nervous system. Here, the human immunodeficiency virus (HIV) infects preferentially microglial cells, which thereby release substances known to interfere with neuronal function. One class of agents set free in this manner are proteases; these degrade certain components within, and thereby undermine the integrity of, the extracellular matrix (ECM) compartment, which plays a vital role in cell-to-cell communication. We wished to ascertain whether the ECM compartment is indeed disrupted in the brains of AIDS victims. We examined the neocortical areas of 27 AIDS autopsy cases, including 9 with diagnosed HIV encephalopathy (HIVE); 8 HIV-seronegative cases with various types of brain lesion, including viral infections, were also included in this study. HIV antigens and DNA were identified by use of immunohistochemistry and in situ hybridization, and ECM components by lectin staining and immunohistochemistry. Of the 27 AIDS cases examined, each of the 9 with HIVE was completely devoid of labeled ECM components; 8 of the 18 without HIVE had incurred substantial losses, and only 2 manifested a normal complement of constituents within this compartment. With respect to stratal and topographic variations, layers II and III were less affected than layers V to VII, as was the frontal cortex relative to other areas. These findings confirmed our expectations of the brain's ECM undergoing degradation following HIV infection, and these changes may well underlie the neurological disturbances manifested in AIDS patients. PMID- 9361308 TI - Identification of a new 'TIGR' mutation in a family with juvenile-onset primary open angle glaucoma. AB - Positional mapping of families segregating for juvenile-onset primary open angle glaucoma (JOAG) has previously identified a locus (GLCIA) for this condition on the long arm of chromosome I. Recently, three mutations in the TIGR gene (Trabecular meshwork Inducible Gluco-corticoid Response protein) have been described in a total of ten familial, three sporadic, and one normal subject. One of the familial cases has also been indicated to be of an adult-onset type. Herein, we report the identification of a new mutation in the TIGR gene in a six generation well-documented Edinburgh family with JOAG. We have sampled and screened the living affected members of this family and identified an 'A'-to-'G' transition at amino acid 337 that has changed the glutamine (Gln) to arginine (Arg). This newly identified mutation resides 27 amino acids 5-prime from the previously reported mutation of Gly-to-Val. This mutation created a new MspI restriction site that has co-segregated perfectly with inherited affected haplotype of the pedigree and, furthermore, it has not been observed in 142 chromosomes of randomly selected subjects of the same population. This report, therefore, confirms the role of the TIGR gene in the etiology of JOAG and adds a new mutation to the three reported previously. PMID- 9361309 TI - Ocular manifestations of autosomal recessive Alport syndrome. AB - Ocular abnormalities are common in X-linked Alport syndrome, but they have not been studied in patients with the rarer autosomal recessive disease. We have examined the eyes of a family with autosomal recessive Alport syndrome. Four of the eight offspring of a consanguineous marriage had renal failure and deafness by the age of 20 years. The diagnosis of Alport syndrome was confirmed on the ultrastructural demonstration of a lamellated glomerular basement membrane (GBM) in one affected family member. Autosomal recessive inheritance was suggested by the lack of linkage to the COL4A5/COL4A6 locus, and by linkage to the COL4A3/COL4A4 locus. All four affected family members had anterior lenticonus (or had had a lens replacement for this) and the three who were examined had a dot and-fleck retinopathy. Neither of the two unaffected offspring who were examined nor the father had these abnormalities. The ocular manifestations of autosomal recessive Alport syndrome are probably identical to those for the X-linked form. Although the mutations in these diseases affect genes for different type IV collagen chains, these chains occur together in the basement membranes of the kidney, eye and ear, and abnormalities in any one may result in the same clinical phenotype. PMID- 9361311 TI - Macular hole formation in Bietti's crystalline retinopathy. A case report. AB - Three years after the initial diagnosis, a 21-year-old healthy man with Bietti's crystalline retinopathy developed unilateral stage 4 macular hole with surrounding macular detachment. The mechanism of macular hole formation, which may or may not be a feature of Bietti's crystalline dystrophy, is not clear. PMID- 9361310 TI - A complex allele (1064delTC and IVS2 + 22ins7) in the peripherin/RDS gene in retinitis pigmentosa with macular dystrophy. AB - Because mutations in the peripherin/RDS gene have been found in retinal dystrophies involving the macula, we examined various types of macular dystrophies from southern France to characterize sequence variations that may be associated with these conditions. DNA sequence analysis of the full coding and flanking regions of the peripherin/RDS gene was performed in fifteen unrelated patients with different types of macular dystrophy, including nine with retinitis pigmentosa (RP). Of the 15 probands with macular disease, two (13.3%) were found to carry a mutation in the peripherin/RDS gene. The recurrent mutation P216S was identified in a pedigree with autosomal dominant RP. A previously unreported complex allele (1064delTC associated with IVS2 + 22ins7) that is predicted to result in the premature termination of peripherin/RDS synthesis was identified in a sporadic case of macular atrophy with RP. We also report eight novel neutral sequence variations in the peripherin/RDS gene, most of them found in the 3' untranslated part of the gene. PMID- 9361312 TI - Focal dermal hypoplasia (Goltz's syndrome). AB - A 17-year-old female with Goltz's syndrome was examined because of visual acuity loss in her right eye. Ocular examination revealed microcornea, iris, choroid and optic disc coloboma in the right eye. There were several erthematous and hyperpigmented areas on the body. Magnetic resonance (MR) imaging of the orbits and brain demonstrated right optic nerve hypoplasia and diffuse cortical and cerebellar atrophy. Skeletal manifestations were short stature, scoliosis, syndactyly, clinodactyly, and osteopathia striata. Dental defects included hypodontia, developmental defects, and malocclusion. There were multiple papillomatous lesions on the lids and perioral skin and the nose was asymmetric. Her mental development was apparently normal. She had left bifid ureter and renal pelvis, scant hair on the pubic and genital region, and poor breast development. Histopathologic examination of the biopsy taken from a characteristic skin lesion revealed attenuated epidermis, hypoplastic dermis, and subcutaneous fat close to epidermis. Immunofluorescence staining was negative for IgG, IgM, IgA, C3, C4, fibrin, and albumin. Ultrastructural examination showed that no viral particles were present. Prometaphase chromosome analysis revealed a normal 46, XX female karyotype. Cortical and cerebellar atrophy can occur in a patient with Goltz's syndrome. PMID- 9361313 TI - Ocular abnormalities in a patient with partial deletion of chromosome 6p. A case report. AB - We report on a patient with a de-novo deletion of chromosome 6p. This male infant presented with multiple systemic congenital defects together with an unusual ocular phenotype. Slit-lamp examination revealed thin, opaque, rectilinear bands within the anterior segment partially connecting iris to corneal endothelium. These were associated with bilateral hyperopia and optic nerve hypoplasia. Ocular abnormalities in such patients have been documented although the number of individuals is small and identical cytogenetic defects are rarely encountered. We compare the clinical findings in this case with previously described phenotypes. Characterisation of such cases is important as it is becoming apparent that deletion of genetic information encoded on chromosome 6p has implications for ocular embryogenesis. PMID- 9361315 TI - Effect of early blockade of bradykinin B2-receptors on the blood pressure phenotype of normotensive and spontaneously hypertensive rats. AB - We evaluated if chronic blockade of bradykinin B2-receptors by the long-acting antagonist Icatibant (D-Arg,[Hyp3,Thi5,D-Tic7,Oic8]-bradykinin) affects blood pressure of rats. Pairs of normotensive Wistar Kyoto rats or spontaneously hypertensive rats were mated and their offspring received Icatibant (25 nmol day 1 per kg body wt., s.c.) or vehicle from the 2nd day until the 7th week of life. Then, the administration of Icatibant or vehicle was continued by i.p. infusion using Alzet osmotic pumps. At 9 weeks of age, normotensive rats given Icatibant showed greater systolic blood pressure (135 +/- 1 vs 115 +/- 1 mmHg in vehicle treated rats, P < 0.01), while heart rate was similar. The group difference regarding blood pressure levels was confirmed by direct intra-arterial measurement. No difference was detected between vehicle- and Icatibant-treated spontaneously hypertensive rats regarding blood pressure increase with aging. In conclusion, chronic blockade of bradykinin receptors by Icatibant alters the adult cardiovascular phenotype of Wistar Kyoto rats, provided that the antagonist is given at the early phases of life. These results suggest that the B2-receptor is essential for the maintenance of cardiovascular homeostasis during development, whereas it does not exert a protective role against the progression of hypertension in a rat model of genetic hypertension. PMID- 9361314 TI - Retinal branch vein occlusion associated with macular dystrophy, maternally inherited diabetes, and deafness. PMID- 9361316 TI - The production system and disease incidence in a national random longitudinal study of Swiss dairy herds. AB - A prospective longitudinal observational study based on a stratified random sample of 113 Swiss dairy farms was conducted between April 1993 and July 1994 with the following objectives: (i) to provide statistically valid estimates of disease frequency in the Swiss dairy cow population, and (ii) to evaluate the feasibility and quality of an intensive farm-based data recording system. During the 15-month study period, farmers were asked to record every health and management event related to their cattle herd. This information was mailed back to the study centre at fortnightly intervals. Additionally, farms were visited regularly to verify received data and to discuss specific problems. During these farm visits, management data were recorded using questionnaires. A complete data set of individual animal events with a total observation time of about 1740 cow years and 275 calf-years was collected and disease-incidence measures were calculated. The most frequent events were reproductive disorders and udder diseases, followed by lameness and metabolic disorders. Experience with the data collection technique used in this study suggests that a farm-based system is effective and reliable, as long as good contact with the farmers is maintained, and incentives to stimulate their motivation are provided. PMID- 9361317 TI - Risk factors for bacterial gill disease in young rainbow trout (Oncorhynchus mykiss) in North America. AB - A retrospective whole-population survey was used to investigate putative risk factors for bacterial gill disease (BGD) in young hatchery-reared rainbow trout in North America. Three sets of analyses were done. The first analysis included as cases all of the hatcheries in which there was at least one outbreak of BGD during the 2-year study interval, regardless of location of the outbreak in the hatchery. The case group for the second analysis was limited to hatcheries for which the BGD outbreak occurred inside the hatch house. The case group for the third analysis was limited to hatcheries for which the BGD outbreak occurred outside of the hatch house. For the logistic regression that combined all cases of BGD (regardless of location of the outbreak), there was a significant association between mortality from bacterial gill disease and previous experience with BGD outbreaks (odds ratio (OR) = 10.1; 95% confidence interval (CI) = 5.6, 18.2), being a commercial trout hatchery (OR = 5.2; 95% CI = 2.6, 10.4), and being a hatchery with an annual salmonid fish production of > 250,000 fish (OR = 2.9; 95% CI = 1.5, 5.7). For BGD outbreaks that occurred in the hatch house, the presence of fish in the hatch house water supply significantly increased the odds of an outbreak (OR = 5.3; 95% CI = 2.2, 12.6), as did the use of ultraviolet radiation to disinfect the hatch house water (OR = 7.5; 95% CI = 2.2, 25.8), previous experience with bacterial gill disease (OR = 19.3; 95% CI = 7.9, 46.8), and being a commercial hatchery (OR = 7.7; 95% CI = 3.2, 18.6). The odds of a BGD outbreak outside of the hatch house was significantly associated with previous experience with BGD (OR = 4.3; 95% CI = 2.2, 8.6) and with being a hatchery with an annual salmonid fish production > 50,000 pounds (OR = 2.5; 95% CI = 1.2, 5.1). PMID- 9361318 TI - Sensitivities and specificities of two ELISA tests for detecting infection with Sarcocystis in cattle of Western Australia. AB - The accuracies of two ELISAs, one using antigen from merozoites of S. cruzi grown in vitro and the other using antigen from cystozoites of S. cruzi, for detecting infection of cattle with Sarcocystis, were evaluated by testing the sera of 303 cattle from 36 Western Australian herds. The results were compared with those obtained by digestion of oesophageal samples collected from the same animals. A similar proportion of infected animals were detected by the three methods. The sensitivity of the assays for detecting infected cattle was comparable (98 and 95% for the assay using antigen from merozoites and cystozoites, respectively), however the specificity (97%) of the assay which used antigen derived from merozoites was significantly higher (P < 0.001) than that (84%) which used antigen from cystozoites. When herds which had at least five animals sampled were considered, the same infected and non-infected herds were detected by the ELISA employing antigen from merozoites and the digestion methods (sensitivity and specificity of 100%). The sensitivity and specificity of the assay using cystozoite antigen were 100 and 67%, respectively. The kappa values for agreement beyond chance between the two ELISAs were calculated as 78% for the animal-based data and 72.5% for the herd-based data. We conclude that because of the high sensitivity and specificity of the ELISA using antigen derived from merozoites, this assay would be a useful and reliable tool for general sero-epidemiological studies into infection with Sarcocystis. PMID- 9361319 TI - Helminthosis in local and cross-bred pigs in the Morogoro region of Tanzania. AB - We investigated the prevalence, burden and types of gastro-intestinal helminths in 424 local and cross-bred pigs kept under different management systems in two climatic zones in the Morogoro region of Tanzania. Coprological examination revealed that 53% of the pigs excreted helminth eggs in their faeces. The median eggs per gram of faeces (EPG) was 500 (range 100-22,000). Local breeds in the Mgeta location with tropical highland climate showed significantly higher prevalence (P < 0.001) and median EPG values (P < 0.001) than the cross-bred animals in the semi-arid area. There was no significant difference in the prevalence (P = 0.90) of helminth infection and egg outputs (P = 0.78) in cross bred pigs raised under the small-scale and semi-intensive management systems in the semi-arid zone. Piglets showed significantly lower prevalence of helminthosis (P < 0.001) than the weaners, growers and adults in both local and cross-bred animals. Median EPGs of growers and adult animals were significantly higher than those of piglets and weaners (P = 0.006). The prevalences of various helminth species were Oesophagostomum sp. (40%), Ascaris suum (12%), Strongyloides ransomi (9%) and Trichuris suis (5%). PMID- 9361320 TI - Risk factors associated with musculoskeletal injuries in Australian thoroughbred racehorses. AB - Risk factors for musculoskeletal injury in racing Thoroughbreds were investigated in a case-control study conducted at racetracks administered by the Australian Jockey Club. Univariable analysis of 137 cases from the official Veterinary Surgeon's reports and an equal number of randomly selected controls from the Australian Race Results identified field size, barrier position and class of race as being significantly associated with breakdown (P < 0.05). Multiple logistic regression was then used to investigate the effect of each putative risk factor whilst controlling for all others. Horses at greater risk were older, started from a wider barrier position, ran at the same distance as their previous race and raced in the highest class of race. There was no significant difference between tracks or significant association with track condition. The incidence of fatalities in the study population was less than that reported in the UK and USA. PMID- 9361321 TI - A simulation model for the spread of bovine tuberculosis within New Zealand cattle herds. AB - Bovine tuberculosis, caused by Mycobacterium bovis, presents a major problem to New Zealand agriculture because of the risk that it poses to export-market access. New Zealand research has focused largely on the epidemiology of the disease in wildlife reservoirs, and relatively little is known about the dynamics of the disease in cattle. This study, therefore, investigates bovine tuberculosis (Tb) dynamics within cattle herds, by construction and application of a simple simulation model of disease transmission. The model was designed firstly to estimate rates of disease transmission within herds, and secondly to identify likely consequences of changes in herd Tb-testing policies. Both deterministic and stochastic versions of the model were used to achieve these aims. The model suggests that within-herd Tb transmission does occur and contributes to the reactor rates observed under annual herd testing regimens. The mass-action disease transmission coefficient (proportion of susceptible animals infected per unit time per infectious animal, i.e. not per diseased animal or per reactor), appears to be in the order of 2.7 x 10(-5) per cow per day for a typical herd of around 200 animals, resulting in a contact rate (number of potentially infectious contacts made per infectious cow per day) of about 0.0073. These are average estimates for both beef and dairy herds. Model results suggest that improving the sensitivity of the test used to diagnose bovine Tb would improve control in areas where wildlife reservoirs are absent but have little effect where they are present. Reducing the time between tests of herds on Tb-induced movement control from the current 6 months to 2 or 3 months reduces the average time a herd spends on movement control and hence national Tb prevalence. In the presence of wildlife reservoirs of infection, both the total number of tests and total reactors per unit time increase, but the extent depends on the level of external infection. In all scenarios examined, involving thousands of model runs in total, infection was invariably absent from the modelled herd by the time it was considered clear of Tb based on testing results. This suggests that the caudal fold test is a realistic measure of herd Tb status and that Tb is unlikely to persist in herds under current testing practices in the absence of anergic cattle or an external source of infection. Specificity of the caudal-fold test as used in practice was estimated to be greater than 99%. PMID- 9361322 TI - Effect of different sampling techniques on odds ratio estimates using hospital based cases and controls. AB - Potential biases introduced by the use of hospital admission records have rarely been discussed in the veterinary literature. Veterinary Medical Teaching Hospital (VMTH) patient records kept at the University of California, Davis (UCD) School of Veterinary Medicine provide a unique opportunity to perform in-depth analyses on the effect of different control selection (sampling) techniques on odds ratio (OR) estimates for disease risk factors in a retrospective case-control study. Horses with Corynebacterium pseudotuberculosis abscesses (134) and the (secondary) study base population (source for controls) were identified, and a 'gold standard' OR for each category of the factors admission type, age, breed and sex was derived. Example data were used to calculate sampling ratios (SRs), defined as the ratio between any sample proportion (of an arbitrary risk factor) and the study base proportion for this risk factor. Sampling ratios different from 1.0 introduced biases into the observed OR estimates, when compared with the 'gold standard' OR. Three randomized samples (simple random, stratified random, systematic sampling), one matched (on date of admission) and three different diagnosis samples ('colic', 'cuts and lacerations', 'fractures') were selected from the study base, and the SRs for all categories of the four factors were derived. The matched and two different disease samples ('colic' and 'fractures') had especially wide ranges of observed SRs (and large errors in the OR estimates), whereas simple random and systematic sampling had comparably narrow ranges (less biased OR estimates). For the three randomized sampling techniques under study, repeated sampling was used to derive SR distributions. The SRs were approximately normally distributed. Analysis of variance and covariance showed that simple random and systematic sampling provided SR distributions with means closest to 1.0 (expected value) and small standard deviations. The OR estimates obtained from records selected by these two sampling techniques therefore were least biased. The findings demonstrate the importance of selecting appropriate sampling techniques in addition to properly defining the study (base) population. Sampling design introduces uncertainty into the OR estimates. The direction of the bias, however, depends on the OR between factor and disease in the source population (the 'gold standard'), and on the direction and magnitude of the SR. When combining the results from single and repeated sampling we conclude that sampling design is most influential on the range of the observed SRs (single samples), on the absolute deviation of the SR from 1.0 (expressed as SR delta Mean) and on the SR standard deviation (SD) (repeated sampling). PMID- 9361323 TI - Quantitative assessment of genomic similarity from restriction fragment patterns. AB - A quantitative algorithm for comparing restriction fragment patterns (RFPs) was developed and used to estimate the genomic similarity of 18 isolates of pseudorabies virus of known origin. Variants of this algorithm using either untransformed or square-root-transformed differences between fragment sizes were investigated with regard to their ability to classify RFPs. Multidimensional scaling was used to represent spatially the genomic relatedness among samples, with 3 dimensions producing the most meaningful results. The square-root transformation provided more interpretable dimensions. The first dimension differentiated samples geographically, separating North American from European isolates. The second and third dimensions differentiated isolates with specific gene deletions (gE and gG, respectively) from those not having these deletions. Clusters of isolates were identified that were related either by collection from the same geographic area during a specific time period, or by laboratory intervention to create vaccines. These methods offer increased precision in the determination of genetic relatedness based on RFPs, and thus offer increased diagnostic accuracy for the determination of sources of infection. PMID- 9361324 TI - A quantitative assessment of the risk of transmission of foot-and-mouth disease, bluetongue and vesicular stomatitis by embryo transfer in cattle. AB - This paper addresses the risks involved when bovine embryos are moved internationally and, specifically, the possibilities of transmitting foot-and mouth disease, bluetongue and vesicular stomatitis by embryos originating from an area in South America. The risk scenario pathway was divided into three phases for analysis. The first phase dealt with the potential for embryo contamination which depends on the disease situation in the exporting country and/or region, the health status of the herds and the donor cows from which the embryos are collected, and the pathogenetic characteristics of the specified disease agent. The second phase covers risk mitigation by use of internationally accepted standards for processing of embryos, and the third phase encompassed the risk reductions resulting from post-collection surveillance of the donors and donor herds, and also from testing of embryo-collection (flushing) fluids for the disease agent. Quantitative risk analysis showed that under the circumstances specified in the paper, the risk of transmission of foot-and-mouth disease and vesicular stomatitis by embryos would be likely to be less than 1 in 100 billion (10(-11.0)) and 1 in 100 million (10(-8.0)), respectively. The values for bluetongue were 1 in 30,000 (10(-4.2)) when embryos were collected in the vector season and 1 in 1 million (10(-6.0)) in the season with low vector activity. These risk values were influenced by the incidence of each disease in the area of origin and the ease with which clinical signs can be recognised. Competent embryo processing according to procedures recommended by the International Embryo Transfer Society were also of great importance. The analysis showed that the reasons for the low levels of risk of transmission differed for each of the three diseases. In the case of bluetongue, vector ecology was of major importance. PMID- 9361325 TI - Sensitization to amphetamine on the differential-reinforcement-of-low-rate 72-s schedule. AB - The purpose of the present study is to determine whether the effect of specific intermittent injections of amphetamine (AMPH) on a differential reinforcement schedule of low rate (DRL) would result in a sensitized response to subsequent AMPH injections. Two groups of rats were trained on a DRL 72-s schedule until they reached stable baseline performance. One group (SENS, n = 8) was treated intermittently (no more than twice a week) with 1.5 mg/kg amphetamine for 3.5 weeks. The other group (CONT, n = 8) received intermittent saline (SAL) 1 ml/kg for 3.5 weeks. Acute injections of 1.5 mg/kg AMPH in the SENS group, engendered an increase in response rate, a decrease in reinforcement rate and disruption of the inter-response time (IRT) distribution profile. Acute SAL injections in the CONT group had no effect. Rats pretreated with intermittent 1.5 mg/kg AMPH, when treated with a lower dose of AMPH (0.5 mg/kg), showed an increase in response rate, a decrease in reinforcement rate and disruption of the IRT distribution profile by decreasing peak area and shifting the peak location towards a shorter IRT duration. Therefore, in rats pretreated intermittently with 1.5 mg/kg AMPH (SENS group), the dose of 0.5 mg/kg AMPH elicited a similar change in DRL 72-s response pattern, as did the acute injection of 1.5 mg/kg AMPH. In contrast, in rats pretreated with SAL (CONT group), the low dose of AMPH had either no or small effects. Thus, pretreatment with 1.5 mg/kg AMPH increases the magnitude of the response to 0.5 mg/kg AMPH. These results indicate that rats performing on the DRL 72-s schedule exhibit sensitization to AMPH, after AMPH is given intermittently over a 3-week period. PMID- 9361327 TI - Isolation rearing enhances the locomotor stimulant properties of intra perifornical sulpiride, but impairs the acquisition of a conditioned place preference. AB - Previous data indicated that infusions of the D2/D3 dopamine receptor antagonist sulpiride within the perifornical region of the lateral hypothalamus may engage neural circuitry relevant to activation of the mesoaccumbens dopamine projection. The present work examined this proposition further. Experiment 1 examined the ability of intra-perifornical sulpiride to induce a conditioned place preference, using an unbiased conditioning procedure. Thus, bilateral guide cannulae were implanted to gain access to the perifornical region of the lateral hypothalamus. Following recovery, animals were subjected to an initial exposure to the place preference apparatus. The apparatus consisted of three distinctive compartments, the central compartment allowing access to the two outermost compartments. Initial exposure indicated equal preference for each. Then, in alternating sessions, animals received infusions of sulpiride (5, 10 or 20 micrograms) before being placed in one of the two outermost compartments, and infusions of vehicle before being placed in the alternate compartment. Compartment-drug pairings were counterbalanced across animals. Four drug, and four saline sessions were completed, each being separated by at least 2 full days. On the final test day, animals were allowed free access to compartments, and the time spent in each was compared with that of initial exposure. Results showed that intra-perifornical sulpiride increased activity during drug-conditioning sessions in an incremental fashion, and supported dose-dependently the acquisition of a conditioned place preference. Experiment 2 examined the effects of isolation rearing upon the locomotor stimulant properties of intra-perifornical sulpiride, and the acquisition of a conditioned place preference. Rats were raised from weaning either alone (isolation-reared) or in groups of five (socially-reared controls) until 4 months of age. Consistent with previous reports of the effects of isolation rearing upon psychomotor stimulant responsivity, here isolates were found to be more responsive to the locomotor stimulant properties of intra perifornical sulpiride, but were less responsive to the ability of intra perifornical sulpiride to support the acquisition of a conditioned place preference. These data were suggested to provide further support for the proposition that blockade of dopamine receptors of the D2 family within the perifornical region of the lateral hypothalamus results in the activation of the mesoaccumbens dopamine projection, via the ventral tegmental area. PMID- 9361326 TI - Comparison of abstinence syndromes precipitated by flumazenil and PK 11195 in female diazepam-dependent rats. AB - The abilities of the central (CBR) and the peripheral (PBR) benzodiazepine receptor antagonists, flumazenil (FLU) and PK 11195 (PK), to precipitate an abstinence syndrome in diazepam (DZ)-dependent rats have been evaluated. Female rats were exposed for 5 weeks to DZ slowly released from SC implanted silastic capsules (90 mg/capsule per week) and thereafter they were challenged in weekly intervals with IV injections of FLU (10, 20, 40 mg/kg) or PK (5, 10, 20 mg/kg), respectively. The maximum abstinence scores tended to increase with the dose of FLU but not with the dose of PK. Although FLU and PK precipitated some common abstinence signs, there were marked differences between these antagonists. FLU evoked dose-related tonic-clonic and clonic convulsions (five out of six rats), whereas PK (10 mg/kg) induced convulsions in only one rat (out of five); tachypnea tended to increase with the dose of both FLU and PK; twitches and jerks, backing and writhing had a significant regression on the dose of FLU; rearing tended to decrease with the dose of PK whereas FLU-evoked head bobbing and PK-evoked twitches and jerks had inverse U-shaped dose-response curves. In comparison to FLU, similar doses of PK (10 and 20 mg/kg) induced a lower precipitated abstinence score (P < 0.05) and a less intense tachypnea (P < 0.05). The data indicate that the chronic continuous exposure to DZ (and/or its active metabolites) affects both CBR and PBR in the rat; however, the abstinence syndromes produced by the CBR and PBR antagonists, FLU and PK, differ in overall intensities and in the diversity of evoked abstinence signs. PMID- 9361328 TI - The effects of haloperidol on visual search, eye movements and psychomotor performance. AB - The effects of single doses of haloperidol (2, 4 and 6 mg) were compared with lorazepam 2.5 mg and placebo in 15 healthy subjects. Visual search strategy was measured, along with a range of psychomotor and eye movement tests. Patients with Parkinson's disease have been shown to exhibit a shift from parallel to serial processing in visual search, but we demonstrated that this does not occur following administration of either haloperidol or lorazepam. Haloperidol was detected by visual analogue rating scales and peak saccadic velocity, the latter being the more sensitive measure. Haloperidol had no statistically significant effect on smooth pursuit position error, velocity error or saccadic intrusions. Digit symbol substitution performance was clearly diminished by haloperidol, but there was no effect on the continuous attention test. Lorazepam decreased performance in all tests apart from saccadic latency. PMID- 9361329 TI - Enhanced stimulus-reward learning by intra-amygdala administration of a D3 dopamine receptor agonist. AB - The amygdala is considered to be a critical neural substrate underlying the formation of stimulus-reward associations, and is known to receive substantial innervation from dopaminergic neurons located within the ventral mesencephalon. However, relatively little is known about the function of the mesoamygdaloid dopamine projection in stimulus-reward learning. Recently, we have found post session intra-amygdala microinjections of d-amphetamine to enhance appetitive Pavlovian conditioning as assessed in a discriminative approach task. In the present study, we have examined the effects of dopamine receptor agonists possessing relative selectivity for the D1, D2 and D3 receptor subtypes in order to examine more fully the role of the mesoamygdaloid dopamine projection in stimulus-reward learning. Thus, subjects were trained to associated an initially neutral stimulus (CS+) with 10% sucrose reward (US). A second, control stimulus (CS-) was also presented but never paired with sucrose reward. In order to measure specifically the conditioned response to CS+/CS- presentation, responding during CS and US presentations was measured separately. Immediately following each training session, subjects received bilateral intra-amygdala infusion of 0.1, 1 or 10 nmol/side of SKF-38393, quinpirole or 7-OH-DPAT. Infusions of SKF 38393 or quinpirole were without effect on CS+ approach. However, post-session intra-amygdala infusions of 7-OH-DPAT enhanced selectively CS+ approach in a dose dependent fashion. No dose of any drug affected CS- approach, US behaviours, or measures of extraneous behaviour. Subsequent acquisition of a novel conditioned instrumental response was also unaffected. Thus, the present data indicate a selective involvement of the D3 dopamine receptor subtype in the modulation of stimulus-reward learning by the mesoamygdaloid dopamine projection. PMID- 9361330 TI - An animal model of copulatory disorder induced by social stress in male mice: effects of apomorphine and L-dopa. AB - We investigated the possible role of dopamine receptors in the mediation of copulatory disorder induced by defeat experience in male mice, using L-dopa and apomorphine. To generate the copulatory disorder, male mice were attacked 20 times daily for 5 consecutive days, as intruders in confrontation with an aggressive resident. Following the repeated exposure to defeat, virtually all intruder males failed to display copulatory behavior towards estrous females. Acute injection of apomorphine (25, 50, 75 micrograms/kg, s.c.) significantly increased both the incidence and the frequency of copulatory elements (mounting and intromission) in a dose-dependent manner. The combination of L-dopa with carbidopa, a dopa decarboxylase inhibitor, also increased significantly copulatory behavior, revealing an inverted U-shaped dose-effect curve. In both cases, locomotion and digging frequencies were significantly decreased. This evidence suggests that dopaminergic mechanisms are involved in the mediation of social stress-induced copulatory disorder. PMID- 9361331 TI - Comparison between the effects of ethanol and diazepam on spatial working memory in the rat. AB - The present study compared the effects of ethanol and diazepam on a task that allows for the assessment of both spatial working memory and the acquisition of spatial information within each day. During the first trial of each day, subjects were shown the spatial location of a food reward on a six-arm radial-arm maze. During nine subsequent free-choice trials, subjects were reinforced for returning to that same spatial location. The location of the food reward varied across days. Thus, choosing correctly on any given trial required subjects to remember where food had been received during the previous trials of that day. The effects of ethanol and diazepam on working memory were assessed by analyzing the overall number of errors committed during the nine free-choice trials of each day. The effects of ethanol and diazepam on within-day acquisition were assessed by comparing the number of errors committed during the first three trials of each day to the number of errors committed during the last three trials of each day. Ethanol and diazepam both produced dose-dependent increases in working memory errors, and both did so without impairing within-day acquisition. The results of the present study provide further evidence of the similarities between the effects of ethanol and benzodiazepine receptor agonists on learning and memory, and are consistent with the hypothesis that ethanol's potentiation of GABA at GABAA receptors contributes to the learning and memory impairments produced by ethanol. PMID- 9361332 TI - Haloperidol enhances latent inhibition in visual tasks in healthy people. AB - We have previously shown that 0.5 mg haloperidol (i.v.) increased latent inhibition in one of two visual tasks. The present study analysed the effects of a higher dose of haloperidol (1.0 mg, i.v.) on latent inhibition in these two visual tasks in healthy volunteers in a randomised controlled trial. In the task where 0.5 mg haloperidol had enhanced latent inhibition, 1.0 mg had the same effect, thus replicating the previous result. In the task where 0.5 mg haloperidol had been ineffective, 1.0 mg haloperidol enhanced latent inhibition in high schizotypal subjects only. This indicates that subjects with higher schizotypy scores are more sensitive to dopamine blockade. A comparison of the results from the studies at the two different doses suggests a dose dependence of haloperidol's effects on latent inhibition that parallels results from animal work. PMID- 9361333 TI - Choice between cocaine and food in a discrete-trials procedure in monkeys: a unit price analysis. AB - In behavioral economics, the unit price (UP) model of drug consumption defines UP as the ratio of the response requirement to the dose of drug. This model makes two predictions: increasing UP will decrease consumption, and consumption at a given UP will be constant regardless of the response requirement and dose that make up the UP. The present experiment was designed to test the UP model in rhesus monkeys allowed to choose between an IV injection of cocaine and food in a discrete-trials choice procedure. Both response requirement/injection and dose of cocaine were varied in such a way as to yield UPs from 40 to 10,000 responses per mg/kg. The response requirement for food was always 30 and there was a 30-min time-out between trials to allow the direct effects of cocaine on responding to dissipate. Consistent with the UP model, cocaine consumption decreased as UP increased. However, at a given UP, cocaine consumption was usually higher at the higher dose. Thus, under the conditions of the present experiment an important component of the UP model of drug consumption was not supported. It may be that UP is not a reliable predictor of consumption under conditions in which the direct effects of a drug on responding are minimized. PMID- 9361334 TI - Indirect in vivo 5-HT1A-agonistic effects of the new antidepressant mirtazapine. AB - The new antidepressant mirtazapine was tested in two experimental procedures which can reveal direct or indirect 5-HT1A receptor agonistic effects. These procedures were observation for induction of lower lip retraction in rats and comparison of stimulus properties in cross-familiarization experiments with conditioned taste aversion in mice. Mirtazapine induced lower lip retraction in rats, as did the 5-HT1A receptor agonist (+/-)-8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT). However, the response to mirtazapine at doses up to 22 mg/kg remained below the maximum score obtained with 8-OH-DPAT (0.46 mg/kg). Blockade of the 5-HT1A receptors with pindolol (10 mg/kg) caused a strong reduction of the lower lip retraction induced both with mirtazapine and 8-OH DPAT. In the cross-familiarization conditioned taste aversion experiments it was found that the conditioned taste aversion induced by mirtazapine (0.32 mg/kg) could be prevented if the mice were pre-exposed to injections with mirtazapine (0.22 and 0.46 mg/kg), 8-OH-DPAT (0.22 and 0.46 mg/kg) and after pre-exposure to the 5-HT reuptake inhibitor fluoxetine (22 mg/kg). No familiarization for the mirtazapine stimulus was obtained by pre-exposure to (+/-)-1-(2,5-dimethoxy-4 iodophenyl)-2-aminopropane HCl (DOI) (0.46-4.6 mg/kg) and MK212 (2.2-22 mg/kg), being agonists for the 5-HT2A and 5-HT2C receptors, respectively. With the reversed sequence, the conditioned taste aversion induced by 8-OH-DPAT (0.22 mg/kg), DOI (1.0 mg/kg) and fluoxetine could be prevented only partially by pre exposure to mirtazapine in a dose of 1 mg/kg. The conditioned taste aversion induced by MK 212 (4.6 mg/kg) was not affected by pre-exposure to mirtazapine (0.1-1.0 mg/kg). On the basis of these results, it can be concluded that mirtazapine has indirect 5-HT1A receptor agonistic properties which may play an important role in the therapeutic effect of this compound. PMID- 9361335 TI - Differential modulation of behavioral effects of cocaine by low- and high efficacy D1 agonists. AB - Dopamine D1 agonists differing in efficacy with respect to stimulation of adenylate cyclase activity and other in vitro and in vivo criteria were evaluated for their capacity to modulate the behavioral effects of cocaine in squirrel monkeys. Monkeys were trained either to respond on a fixed-ratio schedule in which lever pressing terminated a stimulus associated with electric shock or to discriminate cocaine from vehicle using a two-lever drug-discrimination procedure. When administered in combination with cocaine, D1 agonists displaying relatively low efficacy (SKF 38393, SKF 75670) attenuated both the rate-altering effects of cocaine on fixed-ratio responding and the discriminative-stimulus effects of cocaine, resulting in overall rightward shifts of the cocaine dose response functions. Maximal attenuation of the behavioral effects of cocaine by the D1 partial agonists was comparable to that produced by the D1 antagonist SCH 39166. In contrast, D1 agonists displaying relatively high efficacy (SKF 81297, SKF 82958, SKF 83189) either had little effect on or accentuated the rate altering and discriminative-stimulus effects of cocaine. The results show that D1 partial agonists can act as functional cocaine antagonists and may be viable candidate medications for the management of cocaine addiction. PMID- 9361336 TI - Chronic alcohol abuse and the acute sedative and neurophysiologic effects of midazolam. AB - The aim of the present investigation was to examine benzodiazepine sensitivity in abstinent alcoholics. For this purpose, two escalating doses of the benzodiazepine midazolam were i.v. administered to nine alcohol-dependent patients after 2-3 weeks of abstinence and 12 healthy, non-alcoholic volunteers. A variety of dependent measures were examined, including the power spectrum of the resting electroencephalogram (EEG) and evoked EEG responses, saccadic eye movements, self-reported sedation, and vigilance task performance. Analyses revealed a significant association between plasma midazolam levels and changes in EEG beta power, pattern shift visual evoked potential amplitude, heart rate, and saccade amplitude and velocity. The patient and control groups differed significantly in the onset latencies of their saccadic eye movements, and marginally in EEG beta power, both before and after midazolam. However, no differences were detected between the groups in the dose of midazolam required to produce sedation or in midazolam's neurophysiological effects. PMID- 9361337 TI - Self-administration in rats allowed unlimited access to nicotine. AB - The purpose of the present study was to develop an animal model of nicotine self administration that more closely approximates the conditions of human nicotine use than do existing models. In most nicotine self-administration models, rats acquire self-administration during brief daily sessions in which rapid injections of a relatively high dose of the drug, 0.03 mg/kg, serve as the reinforcer. The present study examined nicotine self-administration in rats that acquired the behavior while having virtually unlimited access to injections of a relatively low dose of the drug; the rats did not have any prior operant training or shaping. Under these conditions, rats readily acquire nicotine self administration at doses at least as low as 0.00375 mg/kg per injection, and they self-administer throughout the active portion of their light cycle. The daily nicotine intake of rats, which ranged from 0.18 to 1.38 mg/kg per day, appears to be comparable to that of human smokers. PMID- 9361338 TI - SSRI treatment decreases prolactin and hyperthermic responses to mCPP. AB - We studied the effect of 3 weeks treatment with the selective serotonin re-uptake inhibitor (SSRI), paroxetine (30 mg daily), on the neuroendocrine and hyperthermic responses to the 5-HT2C receptor agonist, m-chlorophenylpiperazine (mCPP) (0.05 mg/kg i.v.), in seven healthy volunteers. Following paroxetine treatment, both the prolactin and hyperthermic responses to mCPP were significantly attenuated. These data are consistent with experimental animal studies indicating that repeated SSRI treatment leads to a functional desensitisation of 5-HT2C receptors. This effect may be linked to the anxiolytic properties of SSRIs. PMID- 9361339 TI - 5-HT2C receptor activation decreases appetite and body weight in obese subjects. AB - We studied the effect of 2 weeks administration of the 5-HT2C receptor agonist, m chlorophenylpiperazine (mCPP), on appetite and body weight in 18 moderately obese subjects in a double-blind, placebo-controlled trial, mCPP caused a small but significant (0.75 kg) reduction in body weight and in subjective ratings of hunger. Plasma prolactin was significantly elevated by the final dose of mCPP. Our data suggest that during 2 weeks treatment in humans, mCPP may continue to activate brain 5-HT2C receptors, and that this effect is associated with decreases in appetite and body weight. PMID- 9361340 TI - The anti-inflammatory potential of adenosine in ischemia-reperfusion injury: established and putative beneficial actions of a retaliatory metabolite. AB - The endogenous metabolite adenosine has been recognized as a protective agent in the setting of ischemia-reperfusion. Because the formation of adenosine during ischemia is closely linked to ATP catabolism, and its actions antagonize the deleterious metabolic and cardiovascular consequences of ischemia, it has been named a "retaliatory" metabolite. During recent years, however, the insight into its diverse scope of anti-inflammatory actions has increased considerably. In this review, the beneficial metabolic and cardiovascular actions of adenosine in ischemia and reperfusion are briefly outlined, followed by an extensive discussion of the established and putative anti-inflammatory actions of adenosine in the inflammatory response to ischemia and reperfusion. It is demonstrated that adenosine interferes with activated neutrophil function, neutrophil-endothelial adhesive interactions, the production and release of various inflammatory mediators, the expression of adhesion molecules, and that it activates cellular antioxidant defense systems, thus providing protective effects at multiple levels in the pathogenesis of ischemia and reperfusion. Finally, several potential pharmacological strategies to enhance the "natural defense mechanism" provided by endogenous adenosine are presented. PMID- 9361342 TI - Antithrombin III supplementation in severe sepsis: beneficial effects on organ dysfunction. AB - Activation of thrombin and of the coagulation system plays an important role in the pathophysiology of sepsis-associated organ dysfunction. Antithrombin III (AT III) is a natural inhibitor of thrombin, a central procoagulatory factor with pleiotropic activities. Experimental supplementation of AT III improved coagulation parameters and ameliorated organ dysfunction. To determine whether long-term AT III supplementation has beneficial effects on organ function, we conducted a randomized, prospective study in surgical patients with severe sepsis. The study evaluated the long-term effect of AT III supplementation (duration of treatment: 14 days). After randomization (AT III vs. control group), AT III was infused continuously over 14 days to obtain plasma AT III activities > 120%. Forty consecutive patients were recruited (20 AT III/20 control group). Eleven patients had a rapid fatal course and did not met the criterion of a 14 day treatment period. From these 11 patients, 8 patients (5 AT III/3 control group) died within 72 h due to septic shock. The remaining 14 AT III patients and 15 controls survived 14 days and showed no differences in baseline parameters of organ function. AT III caused a disappearance of disseminated intravascular coagulation (DIC) in all patients with DIC, whereas in control patients, the frequency of DIC remained constant (p < .05). In AT III patients a progressive increase in oxygenation index (PaO2/FiO2 ratio) and a continuous decrease in pulmonary hypertension index (mean pulmonary artery pressure/mean arterial pressure (PAP/MAP) ratio) indicated an improvement of lung function (p < .05 vs. control). AT III prevented the continuous rise in total serum bilirubin concentration observed in control patients and diminished the frequency of artificial renal support therapy (p < .05). Long-term supplementation with AT III may improve lung function and prevent the development of septic liver and kidney failure in patients with severe sepsis. PMID- 9361341 TI - Potential therapeutic value of lazaroids in endotoxemia and other forms of sepsis. AB - Lazaroids are developed nonglucocorticoid analogues of methylprednisolone with multiple actions, including the scavenging of reactive oxygen species, the attenuation of inflammation, and the stabilization of biological membranes. In various experimental models, lazaroids were shown to enhance recovery from ischemia-reperfusion injury, central nervous system inflammation, oxidant stress, and panendothelial activation and injury; sepsis might be another important indication for the use of lazaroids. Administration of different lazaroids in experimental endotoxemia and other forms of sepsis indeed showed improvement of biological and hemodynamic parameters, attenuation of inflammation, preservation of oxygenation, and protection of endothelial cell integrity. Further research is needed to determine the effects of these drugs on organ function, mediator synthesis and release, and survival, before appropriate therapeutic protocols for their use in clinical sepsis can be developed. PMID- 9361343 TI - Venoarterial CO2 gradient after cardiac surgery: relation to systemic and regional perfusion and oxygen transport. AB - The difference in CO2 tension between venous and arterial blood (delta PCO2) increases in low-flow states. Therefore, delta PCO2 has been suggested as an additional variable in the monitoring of perfusion. We measured CO2 tensions in arterial, mixed venous, hepatic venous, and femoral venous blood in 42 postoperative cardiac surgery patients. Splanchnic and leg blood flow was measured with dye dilution. Forty-three preoperative abdominal surgery patients served as controls. Systemic and femoral delta PCO2 was increased in cardiac patients, whereas there was no difference in splanchnic delta PCO2 between the groups. In cardiac patients, systemic delta PCO2 correlated well with both splanchnic and femoral delta PCO2 (r2 = .74 and r2 = .56, respectively). Femoral delta PCO2 was higher than splanchnic delta PCO2 (1.27 +/- .44 kPa versus .66 +/- .41; p < .001) after cardiac surgery, but not in the control group. The correlation between delta PCO2 and respective blood flow was weak in the whole body, the splanchnic region, and the leg. When splanchnic blood flow was low, systemic and splanchnic delta PCO2 varied widely. In the cardiac patients with an increased systemic delta PCO2 (> .93 kPa), systemic and regional blood flow was low, but there were no differences in systemic or regional oxygen consumption or lactate levels. After cardiac surgery, high systemic delta PCO2 is associated with marginal systemic and regional perfusion. The adequacy of regional blood flow cannot be assessed on the basis of the systemic delta PCO2. PMID- 9361344 TI - Tumor necrosis factor is a brain damaging cytokine in cerebral ischemia. AB - Two contrasting roles, one beneficial and the injurious, have been proposed for tumor necrosis factor (TNF) in the pathogenesis of cerebral ischemia. Reported here are results obtained in a standard model of permanent focal cortical ischemia in rats, in which the volume of cerebral infarction is measured after permanent occlusion of the middle cerebral artery. Administration of neutralizing anti-rat TNF antibodies (P114) into the brain cortex significantly reduced ischemic brain damage (85% reduced infarct volume as compared with preimmune treated controls). Similar results were achieved by systemic administration of CNI-1493, a recently described tetravalent guanylhydrazone compound, which effectively inhibited endogenous brain TNF synthesis and conferred significant protection against the development of cerebral infarction (80% reduced infarct volume as compared with vehicle controls treated 1 h postischemia with 10 mg/kg). P114 anti-TNF and CNI-1493 were each cerebroprotective when given within a clinically relevant time window for up to 2 h after the onset of ischemia. These findings establish an important, pathophysiological role of TNF in mediating the progression of ischemic brain damage, and suggest that inhibiting TNF with CNI 1493 may be beneficial in the future treatment of stroke. PMID- 9361345 TI - Anti-interleukin-12 therapy protects mice in lethal endotoxemia but impairs bacterial clearance in murine Escherichia coli peritoneal sepsis. AB - The overzealous production of proinflammatory cytokines in sepsis can result in shock, multiorgan dysfunction, and even death. In this study we assessed the role of endogenously produced interleukin (IL)-12 in murine models of endotoxemia and Gram-negative peritoneal sepsis. Initial studies indicated that intraperitoneal lipopolysaccharide (LPS) administration to mice induced a significant time dependent increase in plasma, lung, and liver IL-12 levels. Passive immunization with anti-IL-12 serum intraperitoneally before LPS resulted in a marked reduction in plasma levels of tumor necrosis factor and interferon-gamma. Furthermore, we observed an increase in endotoxin-induced mortality in mice transiently overexpressing murine IL-12 using a recombinant adenoviral vector (Ad5 mIL-12) administered intraperitoneally. Neutralization of tumor necrosis factor or interferon-gamma in animals overexpressing IL-12 resulted in significant reductions in LPS-induced mortality, suggesting that the mechanism whereby IL-12 increases LPS-induced mortality is primarily mediated by the enhancement of these cytokines. In contrast, we observed no survival benefit in animals passively immunized with anti-IL-12 serum before the intraperitoneal administration of 2 x 10(8) live Escherichia coli. Interestingly, there was an approximately 70-fold increase in peritoneal fluid E. coli colony-forming units and the early onset of bacteremia in animals treated with anti-IL-12 serum, as compared with control animals. These results indicate that IL-12 is produced in response to LPS exposure, and the neutralization of this cytokine improves survival in endotoxin challenged animals. However, IL-12 represents an essential component of antibacterial host defense, as anti-IL-12 therapy results in significant impairment in the host's ability to clear Gram-negative bacterial infection. PMID- 9361346 TI - Intercellular adhesion molecule-1 (ICAM-1) is expressed on human neutrophils and is essential for neutrophil adherence and aggregation. AB - This study investigated the expression and regulation of intercellular adhesion molecule-1 (ICAM-1) on human polymorphonuclear neutrophils (PMNs), and its potential role in PMN-PMN adherence and aggregation as observed during systemic inflammatory response syndrome. Normal human PMNs were found to express ICAM-1 with 90% positive population, and this expression was augmented by endotoxin (lipopolysaccharide, LPS) and tumor necrosis factor-alpha (TNF-alpha) stimulation. The presence of ICAM-1 mRNA in human PMNs was further detected by reverse transcription-polymerase chain reaction before and after LPS and TNF alpha treatment. Furthermore, incubation of PMNs with LPS and TNF-alpha resulted in significant increases in PMN-PMN adherence and aggregation, while addition of either anti ICAM-1 mAb or anti CD11b/CD18 mAb significantly inhibited LPS and TNF alpha-mediated PMN-PMN adherence and aggregation. These novel findings demonstrate that ICAM-1 is expressed on human PMNs and responsible for PMN aggregation, and suggest that the interaction between ICAM-1 and CD11b/CD18 may be the molecular basis for PMN aggregation and clumping in the microcirculation during systemic inflammatory response syndrome. PMID- 9361347 TI - Cytokines block the effects of insulin-like growth factor-I (IGF-I) on glucose uptake and lactate production in skeletal muscle but do not influence IGF-I induced changes in protein turnover. AB - There is evidence that proinflammatory cytokines are involved in the regulation of muscle protein breakdown in various catabolic conditions but the mechanisms are not fully understood. Previous studies suggest that cytokines reduce circulating and tissue levels of insulin-like growth factor-I (IGF-I) and may block the anabolic effects of the hormone in certain cell types and tissues. We tested the hypothesis that a mixture of tumor necrosis factor alpha, interleukin 1 alpha, and interferon-gamma block the anabolic effects of IGF-I in skeletal muscle. Muscles from burned or unburned rats were incubated in the absence or presence of 1 microgram/mL of IGF-I with or without the addition of the cytokines. As expected, IGF-I stimulated protein synthesis and inhibited protein breakdown in incubated muscles. The cytokines did not influence protein turnover rates in muscles incubated with or without IGF-I. In additional experiments, the effects of IGF-I on glucose uptake and lactate production were tested. IGF-I increased glucose uptake approximately 2.5-fold and stimulated lactate production approximately 5-fold. These effects of the hormone were significantly inhibited by the cytokine mixture. The results suggest that cytokines do not induce protein catabolism by directly inhibiting the anabolic effects of IGF-I in muscle tissue. The inhibitory effects of the cytokines on IGF-I-stimulated glucose transport and lactate production suggest that the lack of effect of cytokines on protein metabolism was not due to a metabolic unresponsiveness of the incubated muscles to the cytokines. PMID- 9361348 TI - Use of selective and nonselective nitric oxide synthase inhibitors in rat endotoxemia: effects on hepatic morphology and function. AB - Endotoxin has profound effects on nitric oxide (NO) production, and considerable controversies exist as to whether these alterations are beneficial or deleterious. Increased mortality has been reported from nonselective inhibition of NO synthase. Results from selective inhibition of the inducible isoform (iNOS) appear largely positive. In a model of rat endotoxemia we have compared the early effects on hepatic morphology and function of selective and nonselective NO inhibition. Two hours after endotoxin injection (5 mg/kg intraportally) the rats were treated with either the selective iNOS inhibitor aminoethyl isothiourea (AE ITU, 10 mg/kg), the nonselective NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg), or normal saline. The animals were observed for another hour. Using an immunohistochemical method, induction of iNOS was demonstrated in various tissues in all slices examined. No unequivocal benefit from NO inhibition was noted. Electron microscopic examination revealed widespread alterations of liver morphology, without obvious differences between the groups. Liver function, as assessed by ketone body ratio, hepatic venous acid base values, and bile production, was generally more adversely affected after NO inhibition. Even with the iNOS selective inhibitor AE-ITU no benefit was noted. We conclude that during the early phases of endotoxemia therapeutic reduction of NO production has no positive effects on liver function or morphology. PMID- 9361349 TI - The relationship between oxygen extraction and venous pH in sepsis. AB - This study was performed to quantify the impact of Haldane effect (HE) on the relationship between O2 extraction (O2Ex; mL O2/dL blood) and venous pH in 247 measurements performed in 91 septic patients (73 patients with intra-abdominal sepsis, 11 with retroperitoneal abscesses, 6 with severe cholangitis, and 1 with gangrenous fasclitis). The severity of sepsis varied from relatively compensated to extremely diseased conditions. This allowed a detailed assessment of the impact of HE over a wide range of cardiorespiratory and metabolic abnormalities. A recently developed model was used to quantify blood CO2 exchange and Haldane relationships and, in particular, the buffering of venous pH allowed by O2Ex (O2 linked H+ binding) on the basis of arterial and mixed venous blood gas measurements. Arterio-venous pH difference (a-vDpH) was .033 +/- .024 (mean +/- SD). It increased with venoarterial CO2 concentration difference (v-aDCO2; mL CO2/dL blood), but the increase was moderated by a simultaneous increase in O2Ex, as the likely consequence of HE: a-vDpH = .006 + .017 (v-aDCO2) - .009 (O2Ex) [r2 = .96, p < < .001]. To confirm this, the moderation of a-vDpH allowed by the HE (DpH) was calculated. A first component, due to O2-linked H+ binding, had a value of .016 +/- .012, and a second component, due to the Haldane-mediated reduction in venous CO2 tension and plasma carbonic acid concentration, had a value of .019 +/- .006. Their sum (total DpH) was .033 +/- .017 and was related directly and strongly to O2Ex: DpH = -.002 + .009 (O2Ex) [r2 = .85, p < < .001], thus confirming the quantitative impact of HE in moderating the decrease in venous pH relative to arterial pH. The loss of this effect was responsible for the larger decreases in venous pH observed in hypodynamic patients developing impaired O2Ex. These results allow an easy quantification of the Haldane component, separated from the other components affecting pH, and are also useful for assessing the protective role exerted by HE against excessive decreases in venous pH in circulatory failure. PMID- 9361350 TI - Sympathetic and renin-angiotensin activation during graded hypovolemia in pigs: impact on mesenteric perfusion and duodenal mucosal function. AB - Sympathetic and angiotensinergic activation reduce splanchnic oxygen delivery during hypovolemia, which may lead to failure of the intestinal mucosal barrier and eventually multiple organ dysfunction. This study integrates sympathetic and angiotensinergic responses with splanchnic hemodynamics and duodenal mucosal function during hypovolemia and evaluates pharmacologic blockade of either system to ameliorate the impact of acute hypovolemia. Chloralose-anesthetized pigs subjected to 20 and 40% blood volume reductions were randomized to controls or administered guanethidine or enalaprilate to block sympathetic and angiotensinergic activation, as assessed by plasma norepinephrine spillover and angiotensin II levels, respectively. Mesenteric and hepatic oxygen delivery/consumption as well as duodenal mucosal alkaline secretion and potential difference were determined. Hypovolemia preferentially increased mesenteric sympathetic outflow and caused a vigorous angiotensinergic activation. Guanethidine and enalaprilate blocked effectively the sympathetic and angiotensinergic responses. Treatment with enalaprilate, but not guanethidine, prevented the reduction of mesenteric oxygenation and duodenal mucosal alkaline secretion and potential difference observed in control animals. The down regulation of mesenteric oxygenation and duodenal mucosal function during hypovolemia can be prevented by administration of enalaprilate, whereas guanethidine is uneffective in this respect. Interference with the reninangiotensin system might be of clinical interest to support mesenteric perfusion and organ function in hypovolemia. PMID- 9361352 TI - Synchronous multicentric osteosarcoma: the case for metastases. AB - OBJECTIVE: There is a current debate whether multicentric osteosarcoma represents synchronous multiple primary osteosarcomas or metastatic disease. The purpose of this report is to evaluate the etiology, presentation, and classification of this entity. DESIGN AND PATIENTS: Six patients ranging in age from 7 to 29 years were studied. The clinical, radiographic, and pathologic findings are reported. In addition, a review of the literature was undertaken. RESULTS: The clinical courses of our six patients as well as a review of the literature suggest that multicentric osteosarcoma represent one extreme of a continuous scale of metastatic osteosarcoma rather than multiple synchronous primary tumors. The presentation is unusual and the clinical behavior distinctive, but the mechanism of spread remains the same: blood-borne and lymphatic-borne. CONCLUSIONS: Our experience with these six patients supports the concept in the recent literature that synchronous osteosarcoma is one extreme of the spectrum of metastatic osteosarcoma. Its unique features are: (1) multiple radiodense lesions that present simultaneously with or without pulmonary metastases; (2) a single "dominant" lesion with multiple smaller lesions; and (3) a uniformly rapid, fatal prognosis. Osteosarcoma should be regarded as a metastatic disease, even when only a single primary lesion is found at the initial presentation. PMID- 9361351 TI - Alterations in hepatic 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase and glucose-6-phosphatase gene expression after hemorrhagic hypotension and resuscitation. AB - The mRNA abundance of several hepatic glycolytic and gluconeogenic enzymes and blood hormone concentrations were determined in hemorrhagic hypotension-induced rats before and after resuscitation with lactated Ringer's. Northern blot analysis of total liver RNA after 30 min of hemorrhage showed control values for phospho-enolpyruvate carboxykinase and fructose-1,6-bisphosphatase mRNA, but significantly lower values for 6-phosphofructo-2-kinase/fructose-2,6 bisphosphatase (6PF2K/FBPase) as well as 2.5-fold increases in glucose-6 phosphatase (Glu-6-Pase) mRNA. The latter finding is in agreement with the greatly reduced intracellular levels of fructose-6-phosphate and glucose-6 phosphate, and the results are consistent with a rapid activation of hepatic gluconeogenesis by the concomitant decrease in 6PF2K/FBPase and increase in Glu-6 Pase. Blood insulin levels were decreased during hemorrhage and with resuscitation, whereas glucocorticoids were increased 1.5-fold in both cases. Glucagon was unchanged during hemorrhage, but was reduced with resuscitation. Lactated Ringer's resuscitation seemed to affect 6PF2K/FBPase only, which was restored to, and even exceeded, control values. In contrast, Glu-6-Pase mRNA was increased to fourfold control values. The increase in Glu-6-Pase and the decrease in 6PF2K/FBPase mRNA is probably at the level of altered transcriptional rates, because insulin, which plays a dominant role in the regulation of these genes, was decreased during hemorrhage. It remains to be determined what factors are causing further induction of Glu-6-Pase gene after lactated Ringer's resuscitation when hepatic glucose metabolism seems to have reverted to the glycolytic mode. PMID- 9361353 TI - Chronic recurrent multifocal osteomyelitis: a radiological and clinical investigation of five cases. AB - OBJECTIVE: To make a detailed evaluation of the clinical and radiological course of five children with chronic recurrent multifocal osteomyelitis (CRMO). Emphasis was laid on the correlation between clinical data and radiological findings. DESIGN AND PATIENTS: Clinical data, histology (n = 11), bone scintigraphy (n = 17), and the plain radiographs (n = 198) of these patients were reviewed. The mean time of observation was 6.6 years (range 1-14.5 years). Thirty-two lesions seen at the time of primary diagnosis (n = 22) or during the course of the disease (n = 10) were evaluated. Twenty-seven foci were located in bone; in five cases the sacroiliac joints were involved. RESULTS: Bone scintigrams showed nearly all foci (31/32) and were especially helpful in clinically asymptomatic lesions (14/32) or foci which were radiographically difficult to detect or not seen at all (8/32). Only 14 of 32 foci were locally symptomatic clinically. In all cases with a short interval (< or = 3 weeks) between the onset of local symptoms and evaluation by plain radiographs (n = 5) osteolysis was shown without a sclerotic margin. All bone lesions with a longer duration of local symptoms (n = 7) revealed a variable radiographic pattern: osteolysis with sclerotic rim in three, a mixed lytic-sclerotic lesion in three and pure sclerosis in one. In two cases low back pain could be ascribed to sacroiliitis. CONCLUSION: Only careful correlation between clinical, scintigraphy and radiographic features permits an accurate assessment of disease activity in CRMO. The bone lesions detected radiographically soon after the onset of symptoms resemble those of acute osteomyelitis. PMID- 9361354 TI - MR assessment of red marrow distribution and composition in the proximal femur: correlation with clinical and laboratory parameters. AB - OBJECTIVE: To correlate the MR appearance of the proximal femur marrow with clinical and blood parameters. DESIGN AND PATIENTS: The proportion of the femoral neck surface area occupied by red marrow was determined on T1-weighted magnetic resonance (MR) images of the hip in a series of 120 subjects, aged from 15 to 75 years, with ten females and ten males per decade, and correlated with clinical data. This parameter and the bulk T1 values of femoral red marrow were determined in 30 other subjects 25-46 years of age and correlated with their blood parameters. RESULTS: In the series of 120 subjects, the proportion of red marrow surface area decreased with age (P < 10(-4)) and was higher in female than male subjects (P < 10(-4)). Within each decade, the proportion of red marrow surface area was higher in females than in males between 25 and 65 years but neither before 25 nor after 65 years. In the series of 30 subjects, the proportion of red marrow surface area and bulk T1 values of femoral red marrow were significantly negatively correlated with hemoglobin blood levels but not with blood cell counts. CONCLUSION: The MR appearance of proximal femur red marrow is influenced by age and sex. A relationship with hemoglobin blood level is demonstrated. PMID- 9361355 TI - Malposition of the tibial tubercle during flexion in knees with patellofemoral arthritis. AB - OBJECTIVE: To assess the mechanisms contributing to the induction of patellofemoral arthritis (PF-OA). DESIGN AND PATIENTS: A computed tomography scan was taken at three levels of the lower extremity in full extension and at 30 degrees of flexion. The cuts were superimposed and 12 parameters were compared in 17 PF-OA knees and 27 normal knees to assess the rotation angle of the tibial tubercle. RESULTS: Although the tibial tubercle was in almost the same position in full extension in the normal and PF-OA knees, it was positioned significantly laterally at 30 degrees of flexion in PF-OA knees. Also the articular surface of the lateral femoral condyle was significantly narrower or steeper in PF-OA knees. CONCLUSION: Anatomic variations and mechanical abnormalities were identified in the PF-OA knees. PMID- 9361356 TI - Giant calcifying epithelioma of Malherbe (pilomatrixoma): imaging features. AB - We present a case of giant calcifying epithelioma of Malherbe (pilomatrixoma) in the right upper arm of a 62-year-old man. It measured 18 x 12 x 8 cm in size, making it the largest of all the cases reported previously. CT clearly demonstrated a well-defined, subcutaneous mass with amorphous calcifications. The mass showed intermediate signal intensity on T2*-weighted MR images and slight contrast uptake on contrast-enhanced MR images. Histopathologically, this tumor showed no aggressive or malignant nature. The patient is without evidence of recurrence or metastasis 3 years following the resection. PMID- 9361357 TI - Epithelioid sarcoma with unusual radiological findings. AB - The case of a patient with epithelioid sarcoma in the right arm is reported. The diagnosis was delayed because of misinterpretation arising from complexity in the MR findings, including a honeycomb pattern in the subcutaneous fat simulating lymphedema, and an intramuscular diffuse high signal intensity on T2-weighted images without a discrete mass lesion. The histological findings revealed that the diffuse muscular abnormality mainly resulted from denervation of the muscles due to perineural invasion by the tumor, and subcutaneous edema from lymphedema secondary to lymphatic tumor spread concurrent with lymphatic fibrosis. Multiple foci of cortical erosions in the humerus, a rare manifestation of this tumor, were detected 6 months later. PMID- 9361358 TI - Infantile myofibromatosis. AB - Infantile myofibromatosis is a mesenchymal tumor most commonly seen in infancy. The tumors have a variable appearance on CT/MR and often simulate a more aggressive neoplasm. This report describes CT/MR findings in cases of infantile myofibromatosis with pathologic correlation. Discussion into the success of imaging in suggesting the correct diagnosis is also addressed. PMID- 9361359 TI - Radiographic appearance of an ossifying fibromyxoid tumor of soft parts. AB - This case report describes an ossifying tumor in the left musculus erector spinae in a 32-year-old man. Radiologically it showed irregular lamellar bone formation in the periphery, demonstrating as juxtacortical and macroscopically sarcoma-like features. Histologic it was diagnosed as an ossifying fibromyxoid tumor of soft parts (OFTSP). The CT features of this tumor have never previously been reported. This is the first time pulmonary metastases, malignant pleural effusion, and death of the patient directly related with an OFTSP have been described. PMID- 9361360 TI - Sclerosing epithelioid fibrosarcoma: short T2 on MR imaging. AB - A case of sclerosing epithelioid fibrosarcoma and its appearance on MRI is presented. The tumor showed a zonal architecture on MRI with a large central core of very low signal intensity and a peripheral rim of intermediate to high signal intensity on T1- and T2-weighted spin echo pulse sequences. The core showed decreased cellularity with dense collagen deposition on histologic examination, and the peripheral zone increased cellularity with increased nuclear atypia. The presence of a prominent region of very low signal intensity on T1- and T2- weighted images can be seen with neural tumors, giant cell tumor of the tendon sheath, aggressive fibromatosis, and, in rare instances, with soft tissue sarcomas rich in collagen. PMID- 9361361 TI - Gluteal manifestation of advanced Hodgkin's disease. AB - Hodgkin's disease (HD) is a nodal malignancy with a characteristically axial pattern of spread and with contiguous progression via lymphatic channels. Even when dissemination occurs beyond the lymphoreticular system, certain patterns of associated spread are frequently evident. We describe a case of nodular sclerosis HD with a 12-year indolent course and late involvement of the gluteal muscle. Initially, stage was IVb with spleen and bone marrow involvement, complicated by a Coomb's positive hemolytic anemia. Following chemotherapy, the patient had a partial response with the subsequent long course of slowly progressive disease invading first the urinary bladder and, later, the gluteus. Involvement of the gluteal muscle is a rare event in HD. Spread to the gluteus occurred most likely by contiguity, via retroperitoneal lymph nodes. PMID- 9361362 TI - Gouty tophus simulating soft tissue tumor in a heart transplant recipient. AB - Gouty arthritis is the most frequent rheumatological complication among cyclosporine-treated organ transplant recipients. We report one case of pseudotumoral intramuscular tophaceous deposit of the forearm, in a heart transplant patient with a history of traumatic wound to the same area 17 years previously, and with no known arthritis. PMID- 9361363 TI - Phosphodiesterase inhibitors piroximone and enoximone inhibit platelet aggregation in vivo and in vitro. AB - The phosphodiesterase type III inhibitors piroximone (PIR) and enoximone (ENO) exert positive inotropic and vasodilating effects in patients with severe heart failure. PIR and ENO raise cyclic AMP levels in cardiac and vascular smooth muscle cells. Platelet activity is also regulated by intracellular levels of cyclic AMP. In this study we have investigated the effects of PIR and ENO on platelet activity in vivo and in vitro. PIR and ENO inhibited ADP induced platelet aggregation in a time- and concentration-dependent manner with IC50 values of 67 +/- 14 mumol/l and 129 +/- 6 mumol/l, respectively. Coincubation of PIR with the adenylate cyclase activator iloprost resulted in a synergistic potentiation of the platelet inhibitory effect. In anesthetized rats PIR and ENO (2 mg/kg bw) exerted an effective inhibition of collagen induced reduction in peripheral platelet count (vehicle 49 +/- 7%, PIR 22 +/- 8%, ENO 30 +/- 6%; P < 0.01). In washed human platelets incubation with PIR and ENO resulted in a time- and concentration-dependent increase of the intracellular second messenger cyclic AMP. In Fura-2 AM loaded platelets PIR and ENO diminished PAF induced Ca2+ mobilization concentration dependently. Thus, the observed antiplatelet effects following PIR and ENO might exert beneficial effects in patients with cardiovascular disease. PMID- 9361364 TI - Haemostasis balance disorders in patients with essential hypertension. AB - This study was aimed at investigating haemostasis parameters in patients (pts) with arterial hypertension (AH) before any medical treatment and to correlate these findings with those in healthy normal Greek population 83 pts (48 m, 35 w) mean age 49.8 +/- 10.1 yrs, body mass index 23.4 +/- 1.5 with mild to moderate AH and 42 healthy volunteers matched for sex (24 m, 18 w), age 51.2 +/- 10.5 yrs and body mass index 22.8 +/- 1.46 were studied. Fibrinogen, vWF, plasminogen, ECLT, a2 antiplasmin, tPA-Ag, PAI-1 in all pts and in the control group were measured. Mean age and BMI did not significantly differ between the two groups. The hypertensive patients had significantly higher levels of fibrinogen (327.75 +/- 51.36 vs. 272.84 +/- 46.8 mg/dl), tPA-Ag (8.81 +/- 3.32 vs. 5.76 +/- 2.54 ng/ml) and PAI-1 (11.8 +/- 10.9 vs. 7.91 +/- 5.5 IU/ml), whereas a2 antiplasmin level was significantly lower (98.71 +/- 15.40 vs. 107.84 +/- 17.52%). No differences were found between hypertensives and normal subjects in vWF, plasminogen and ECLT. These preliminary data suggest that in pts with mild to moderate AH, before any medical treatment, there are significantly higher levels of fibrinogen, tPA Ag and PAI-1 compared with normal volunteers, whereas there are significantly lower a antiplasmin levels. These findings indicate a disturbance in the haemostasis balance with hypercoagulability and fibrinolytic deficiency. PMID- 9361365 TI - Blocking platelet aggregation inhibits thromboxane A2 formation by low dose agonists but does not inhibit phosphorylation and activation of cytosolic phospholipase A2. AB - Inhibition of aggregation by Ro 44-9883, a potent and selective non-peptide GPIIb/IIIa antagonist, resulted in inhibition of serotonin secretion induced by weak agonists such as ADP or low doses of either thrombin receptor agonist peptide (TRAP) or collagen. In contrast, alpha granule secretion was inhibited to different extents dependent on donor, averaging 60% inhibition. Inhibition of serotonin secretion correlated with an inhibition of thromboxane A2 (TxA2) formation, both of which were overcome by higher doses of TRAP or collagen. Ro 44 9883 had no effect on the already reduced serotonin secretion and TxA2 formation in Glanzmann's thrombasthenic platelets. Restoration of serotonin secretion in the absence of aggregation requires both TxA2 and lysophosphatidic acid. In addition, Ro 44-9883 inhibition of TxA2 formation was not due to a lack of phospholipase A2 (PLA2) phosphorylation and activation as assayed in vitro. These results suggest that aggregation is required for weak or low dose agonist induced in vivo activity of PLA2, possibly by either regulating phospholipid substrate availability or interaction of PLA2 with platelet membranes. PMID- 9361366 TI - The characterization of potent novel warfarin analogs. AB - Racemic sodium warfarin, Coumadin, is widely used in the prevention of thromboembolic disease. The present study was undertaken to characterize three novel classes of warfarin analogs, and to compare them with the warfarin enantiomers. All three classes of compounds inhibit vitamin K epoxide reductase, the enzyme inhibited by racemic warfarin. The alcohol and the ester analogs have reduced protein binding compared with R-(+)-warfarin. The ester and the fluoro derivatives have similar in vivo anticoagulant activity in the rat to that of S-( )-warfarin. Thus, it is possible to synthesize novel warfarin analogs that differ from racemic warfarin or its enantiomers in certain selected properties. PMID- 9361367 TI - Dissociation between the anti-aggregatory & anti-secretory effects of platelet integrin alpha IIb beta 3 (GPIIb/IIIa) antagonists, c7E3 and DMP728. AB - The effects of alpha IIb beta 3 antagonists on the blockade of fibrinogen binding to platelet alpha IIb beta 3 are well documented, however, little is known about their effects on platelet secretion. We compare here the effect of two potent alpha IIb beta 3 antagonists, c7E3 and DMP728, on platelet secretion. Using human platelet-rich plasma, P-selectin expression was measured by flow cytometry and type 1 plasminogen activator inhibitor (PAI-1) secretion as well as beta thromboglobulin (beta-TG) were determined by ELISA. At various concentrations of the antagonists that inhibited 80-95% of platelet aggregation, neither had any effect on P-selectin expression. In contrast, thrombin-stimulated PAI-1 secretion is only inhibited by c7E3, 49.6% at 3.5 mumol/L (p < 0.05), but not at any other maximally effective anti-aggregatory concentrations of c7E3 or DMP728. Furthermore, a lack of any significant effects on platelet granular secretion of beta-TG induced by either thrombin or ADP was demonstrated with DMP728, c7E3 or LM609. Two protein kinase inhibitors, staurosporine and herbimycin, blocked both ADP and thrombin-induced P-selectin expression at 10 mumol/L, but not PAI-1 secretion. Taken together this suggests that: (1) the mechanism of platelet granular secretion is independent of the integrin alpha IIb beta 3 and (2) the subcellular locations of PAI-1, beta-TG and P-selectin or the signaling mechanisms that regulate their secretion might be different. Although there is no direct effect of platelet alpha IIb beta 3 antagonists on platelet secretion of PAI-1, beta-TG and P-selectin, the present data demonstrates that reduction of platelet number by alpha IIb beta 3 antagonists, via the reduction in thrombus size, might be an alternate mechanism for reduced platelet secretion. In conclusion, a discoupling between the anti-aggregatory and the anti-secretory effects of alpha IIb beta 3 antagonists has been demonstrated. PMID- 9361368 TI - Inhibition of platelet deposition with local delivery of heparin using a double balloon catheter. AB - Heparin is an effective agent in the treatment of unstable angina and myocardial infarction. The clinical utility of heparin is limited by bleeding complications. This study was performed to determine whether static delivery of heparin could effectively inhibit further platelet deposition. Thrombogenic graft segments were incorporated into chronic arteriovenous shunts in pigs. Autologous platelets were labeled with 111Indium. Platelet deposition was quantitated with gamma camera imaging. The grafts were exposed to blood flow for 15 min in order to induce platelet deposition on the thrombogenic surface. Heparin was delivered locally either by direct exposure or with a double balloon catheter. After a 15 minute exposure period, the heparin solution was removed and subsequent platelet deposition was monitored for 90 minutes. Heparin, administered with the double balloon catheter in doses as low as 12.5 U, effectively inhibited further platelet deposition. An intravenous injection of 100 U of heparin, the highest dose use for local delivery, did not perturb bleeding time or the activated partial thromboplastin time. In conclusion, platelet deposition can be inhibited with static local delivery of heparin at doses that are not associated with systemic bleeding. PMID- 9361369 TI - Efficacy of pentasaccharide in a dog model of hemodialysis. AB - A synthetic heparin pentasaccharide with sole anti-Xa actions has been evaluated for its antithrombotic efficacy in a dog model of hemodialysis. Various dosages of pentasaccharide, 400-800 nmol/kg, were compared with a single bolus dose of unfractionated heparin (250 U/kg). The primary endpoint in these studies was the duration of dialysis time. In addition, dialyzer filter content, venous trap protein, celite and saline ACT and hematocrit measurement. Pentasaccharide at dosages of 600 and 800 nmol/kg produced an extension of dialysis time (> 180 minutes) in contrast to unfractionated heparin at 250 U/kg which only produced antithrombotic effects for periods of up to 150 +/- 42 minutes (n = 5). At a lower dosage of 400 nmol/kg pentasaccharide produced weaker effects and the dialysis circuit was patent for periods of 122 +/- 14.8 (n = 5) minutes. The saline and celite ACT times were not extended at any dosage of pentasaccharide; however, at 250 U/kg, a strong effect was noted with unfractionated heparin (> 800 secs, 647 +/- 211 secs.), respectively. A dose dependent antithrombotic effect was also evident in the studies on the filter clots and venous trap protein content. No difference in the hematocrit was noted in any group. These results clearly suggest that despite the fact that pentasaccharide does not produce any prolongation of the coagulation times, it produces a dose dependent antithrombotic effect in this model of dog hemodialysis. Furthermore, these results also suggest that pentasaccharide at an appropriate dosage can be used as an alternate antithrombotic agent during hemodialysis. PMID- 9361370 TI - Impact of mutations at the P4 and P5 positions on the reaction of antithrombin with thrombin and elastase. AB - Antithrombin (AT) is a serpin capable of trapping thrombin (IIa) in a stable and covalent complex. Complex formation is prevented by leukocyte elastase (LE) cleavage near the AT reactive centre. We mutated the known LE cleavage sites of AT to explore the possibility of producing an LE-resistant AT molecule. Initially, six rabbit AT variants differing only at residue 390 (P4) were generated in a cell-free system, and gel-based assays were used to assess IIa mediated complex formation and LE-mediated cleavage of the variants. Substitution of charged residues (Glu or Arg) reduced complex formation by 50-60%, while the Ser variant was incapable of inhibiting thrombin; LE reactivity was less affected. The least (Trp) and most (Ser) affected variants were expressed in COS 1 cells. Again, the Ser variant was incapable of detectably reducing the rate of thrombin-mediated amidolysis while the Trp variant inhibited thrombin at a slightly reduced rate (-28%). LE inactivated the Trp variant and the wild-type AT to a similar extent. Recreation of the Trp mutation in COS-derived human AT showed similar results. Since retention of LE-sensitivity could have arisen due to cleavage at Val389 (P5), we produced and characterized a human AT substitution mutant with Trp at both P4 and P5. This variant showed a slight reduction in thrombin inhibitory activity (-22%), but remained susceptible to LE inactivation. These results suggest either that LE cleaves at secondary sites if its primary cleavage sites are blocked, or that the substrate specificity of LE differs in polypeptides as compared to peptide substrates. PMID- 9361372 TI - Influence of garlic compared to aspirin on induced photothrombosis in mouse pial microvessels, in vivo. AB - Effect of garlic on photochemically-induced platelet aggregation in pial microvessels of the mouse, in vivo, was compared to that of acetyl salicylic acid (ASA). Three trials were carried out, in which garlic at doses of 12.5, 25, 50 and 100 mg/kg and ASA doses of 25, 50 and 100 mg/kg were used. Each trial included treatment groups of male mice, approximately 30 g, and a control group. Animals were anesthetized (urethane, 1-2 mg/g, i.p.), the trachea was intubated and a craniotomy was performed. Induction of platelet aggregation was made by activation of circulating sodium fluorescein (0.1 ml of 5% solution/25 g, i.v.) with an intense mercury light. Garlic, ASA and vehicle solutions were injected, i.p., 60 min prior to the photochemical insult. The time for the first platelet aggregate to appear in pial arterioles was significantly delayed (P < 0.001) only by the 100 mg/kg garlic dose and by all ASA doses. The effect of this garlic dose on first aggregate was comparable to that of the 25 and 50 mg/kg ASA doses. Only the ASA doses delayed (P < 0.05) the appearance of first aggregate in venules. Arteriolar and venular diameter changes were not different among groups of all trials. Data of this study documented that garlic was capable of delaying platelet aggregation in mouse pial arterioles, in vivo. PMID- 9361371 TI - Platelet responses to several agonists and combinations of agonists in whole blood: a placebo controlled comparison of the effects of a once daily dose of plain aspirin 300 mg, plain aspirin 75 mg and enteric coated aspirin 300 mg, in man. AB - Platelet responses to several agonists and combinations of agonists have been measured in whole blood from healthy volunteers. We have determined the effects of once daily treatment for five days with plain aspirin 300 mg, plain aspirin 75 mg, enteric coated aspirin 300 mg or placebo. Measurements were made of platelet aggregation (using a platelet counting technique) and the release reaction (14C 5HT release from pre-labelled platelets). The extents of these responses before aspirin administration depended on the agonist used. ADP, adrenaline and PAF failed to induce any 14C-5HT release in most subjects, but combinations of these agonists acted synergistically to produce extensive 14C-5HT release. All three aspirin preparations reduced the extent of the platelet responses to most agonists: platelet aggregation induced by collagen, ristocetin and arachidonate and 14C-5HT release induced by collagen, streptokinase, and various combinations of ADP, adrenaline and PAF. None of the preparations had any effect on the aggregation that occurred in the absence of an agonist (spontaneous aggregation), but they all reduced streptokinase-induced aggregation to control (spontaneous) levels, and abolished the 14C-5HT release induced by arachidonate and by ristocetin. All three aspirin preparations were equally effective after two daily doses. No further inhibition of platelet responses was obtained after five daily doses. Plain aspirin 300 mg achieved its maximal effect after only a single dose, but enteric coated aspirin 300 mg (and sometimes plain aspirin 75 mg) produced sub-maximal inhibition after only a single dose. Parallel investigations on the effects of these aspirin regimes on gastric mucosal prostaglandin E2 synthesis and gastroduodenal mucosal injury were performed. These results will be reported separately. PMID- 9361373 TI - Collagen-induced platelet aggregation and release reaction: role of ras protein. AB - The relationship between the platelet collagen receptor and ras protein was examined by immunoprecipitation of control and collagen stimulated platelets with both antibodies. Both ras protein and receptor are coprecipitated by both antibodies. The coprecipitated samples contained GTP and GDP which were separated by thin layer chromatography. The effect of guanine nucleotide binding protein (G protein, 21ras) on platelet aggregation was examined by using a guanine triphosphate analogue (GTP-gamma-S). Results of streptolysin O permeabilized experiments show that the addition of the analogue to permeabilized platelet-rich plasma causes platelet aggregation and release of ATP in a dose-dependent fashion. The aggregation induced by GTP-gamma-S could not be obtained with GDP, GDP-beta-S, or 5'-GMP, suggesting that the effect of GTP-gamma-S is specific. The platelet aggregation induced by the analogue was inhibited in a dose-dependent manner by phenylmethanesulfonyl fluoride (PMSF) but not apyrase. GTP-gamma-S induced thromboxane B2 formation was also decreased by PMSF. Formation of thromboxane B2 was also blocked by the addition of PMSF and ethanol suggesting that GTP-gamma-S increases arachidonic acid release from permeabilized platelets. These results suggest that both GTP-gamma-S and GTP enhance phospholipase A2 activity which releases arachidonic acid in permeabilized platelets and subsequently causes platelets to aggregate. PMID- 9361374 TI - Tissue factor expression in human monocytic cell lines. AB - Tissue factor (TF) is a main initiator of the coagulation protease cascade. Control of the expression of this protein in monocytes is essential, since these cells are the only circulating blood cells responsible for TF expression. In this report we have used two human cell lines, arrested at different stages of monocytic differentiation, to study TF expression. The monoblastic cell line U 937 had a constitutive expression of TF surface protein and low TF mRNA levels detected by immunofluorescence or quantitative reverse transcriptase polymerase chain reaction respectively. The phorbol-12-myristate-13-acetate (PMA) was a potent enhancer of TF expression in U-937. Lipopolysaccharide (LPS) and tumor necrosis factor (TNF) had no effect on TF expression in U-937. The Mono Mac 6 cell line, with phenotypic features similar to that of mature monocytes, expressed lower basal levels of TF mRNA and surface TF antigen. However, in Mono Mac 6 cells TF expression was induced in response to LPS and TNF. These results indicate differences in basal and induced TF expression between U-937 and Mono Mac 6 cell lines. PMID- 9361375 TI - L-arginine infusion decreases platelet aggregation through an intraplatelet nitric oxide release. AB - Nitric Oxide (NO) inhibits platelet aggregation via activation of an intraplatelet soluble guanylate cyclase which induces an increase in cyclic GMP (1). It has been also demonstrated that platelets contain a constitutive, calcium dependent, NO synthase which is activated by collagen-induced platelet aggregation. This leads to a NO synthesis from L-Arginine (L-Arg), which in turn increases cyclic GMP and down-regulates platelet aggregation (2). In vitro administration of supraphysiological concentrations of L-Arg enhances platelet cyclic GMP levels by increasing NO production and reduces platelet aggregation. This effect is reversed by pre-incubation with NO-synthase inhibitors (3). These results indicate that the L-Arg: NO pathway plays an important role in the modulation of human platelet aggregation (4). In vivo L-Arg, when administered i.v., induces hypotension (5) and vasodilatation (6,7) in humans, and when orally supplemented reduces platelet aggregability both in hypercholesterolemic rabbits and healthy men (8,9). PMID- 9361376 TI - Effects of coronary angioplasty on monocyte tissue factor response in patients with stable or unstable angina. AB - Balloon coronary angioplasty is a revascularization procedure which increases the luminal diameter at a site of arterial stenosis, leading to mechanical disruption of the atherosclerotic plaque and to stretching of the vascular wall (1). This procedure can be complicated by thrombosis or restenosis, which occur in 5% and 30% of the cases respectively (2). These complications probably result from exposure of blood to components of atherosclerotic plaque, subendothelium and components of vascular wall, leading to activation of coagulation (thrombin generation) and platelets (3,4). Recent data point to simultaneous increase of leukocyte adhesive receptors, indicating an additional process of leukocyte activation, which could play a key role in the vascular healing process after angioplasty (5). These elements could also play a role in the thrombotic and stenotic complications. PMID- 9361377 TI - Inhibition of collagen-induced platelet aggregation by argatroban in patients with acute cerebral infarction. AB - Platelet aggregation induced by collagen is enhanced in patients with cerebral thrombosis [1], and platelet aggregates and activation products such as beta thromboglobulin appear in the circulation, particularly during the acute phase [2]. It is known that the presence of activated platelets markedly amplifies thrombin generation by the prothrombinase complex. Platelet aggregation, for which thrombin is the most potent stimulator, is effected by the activation of the thrombin receptor. Activated platelets likely provide the principal surfaces on which intrinsic coagulation factors and prothrombinase assemble in vivo. Moreover, the blood coagulation cascade is simultaneously enhanced during the acute phase of cerebral infarction, resulting in thrombin production and fibrin formation [3]. Cerebral arterial thrombosis is thought to be initiated by rupture of atherosclerotic plaque. Platelets adhere to the constituents of the plaque, and platelet aggregation and the formation of thrombin occur rapidly. The presence of activated platelets involving thrombin generation in cerebral infarction remains to be further clarified. The present study in patients with acute cerebral infarction was undertaken to determine whether argatroban, a direct thrombin inhibitor, is effective in inhibiting collagen-induced platelet aggregation. It is well known that argatroban inhibits not only thrombin cleavage of fibrinogen with a Ki of 19 nM, but also thrombin-mediated platelet activation with a Ki of 40 nM [4]. We evaluated whether the sensitivity of platelets to collagen is increased in the presence of a trace amount of thrombin associated on platelets, at a concentration that does not induce platelet aggregation in acute cerebral infarction. The study also measured the inhibitory effect, if any, of the addition of argatroban during platelet hyperactivation induced by collagen. PMID- 9361378 TI - Whole-cell and periplasmic protein banding patterns of environmental and human Bacteroides fragilis strains. AB - In order to investigate the relationship among virulent and avirulent Bacteroides fragilis strains, SDS-PAGE of whole-cell proteins (WP) and periplasmic proteins (PP) were used to establish a protein profile of strains isolated from human infections, fecal flora and environmental water. Despite different sources of the strains, no significant differences were observed as determined by the WP SDS PAGE analysis. In contrast, the proteins obtained from the bacterial periplasm showed differences in the electrophoretic protein profile. Two distinct PP profile patterns were obtained. Pattern A included 6 out of the 8 virulent strains and pattern B, 6 out of 8 avirulent strains. Interestingly, an environmental strain that was capable of inducing abscesses in mice, had a PP profile highly similar to that of the virulent strains from human infections. These data indicate that PP from B. fragilis may be useful to characterize differences among virulent and avirulent strains. Moreover, strains isolated from environmental water may also be a source of exogenous infections by B. fragilis. PMID- 9361379 TI - Further studies of the relationships among strains classified as taxon 15, taxon 18, taxon 20, (Pasteurella) granulomatis or the (Pasteurella) haemolytica-complex in ruminants using quantitative evaluation of phenotypic data. AB - Ninety-three trehalose-negative (P.) haemolytica-like strains of ruminant, porcine and leprine origin were investigated. A quantitative evaluation of phenotypic tests was used and the results obtained were compared with those from 246 previously investigated ruminant strains. Cluster analysis of the results obtained displayed most of the taxa as distinct groups which could be related to differences in key characters. Although only minor phenotypic differences were observed between the taxa investigated and the taxa were internally heterogeneous for many of the tests, it was possible to identify characters separating most groups. However, in three instances, taxa isolated from different species could not be separated by any of the tests used or by quantitative evaluation of all 79 tests--the only difference being the species of animals from which they had been isolated. Taxa which could not be separated by phenotypic tests included the ruminant biogroup 6 of (P.) haemolytica and the porcine taxon 15/biovar 1, the ruminant biogroup 7 of (P.) haemolytica and the porcine taxon 15/biovar 2, and ruminant biogroup 31 of (P.) haemolytica and the leprine taxon 20/biovar 1. PMID- 9361380 TI - Genotypic relationships among strains classified under the (Pasteurella) haemolytica-complex as indicated by ribotyping and multilocus enzyme electrophoresis. AB - Two-hundred and one strains classified under the (Pasteurella) haemolytica complex isolated from cattle, sheep, deer, pigs, hares and rabbits were investigated by ribotyping. Fifty-nine of these strains were selected for further studies using multilocus enzyme electrophoresis (MEE). A correlation between the clusters identified by ribotyping and MEE was demonstrated and the results furthermore indicated that a genetic basis exists for most clusters previously outlined by the use of quantitative evaluation of phenotypic data. The taxonomic relevance of ornithine decarboxylase and fermentation of L-arabinose, D-sorbitol and glucosides for taxonomic delineation within the (P.) haemolytica-complex was supported. A taxonomic importance was further indicated for ONPG, ONPX, ONPF, meso-inositol, D-xylose, maltose, dextrine and NPG in relation to some of the taxa. Within the porcine taxon 15, however, differences in ornithine decarboxylase did not correspond to genetic clusters. Six lineages were revealed by MEE. Lineage A contained electrophoretic types (ETs) representing biogroups 1, 3A-3H, 8A and 9, indicating a genetic relationship between these groups--an observation which was supported by ribotyping. Lineage B included biogroup 8D, 3 strains from biogroup 10 and a single strain from biogroup 1 and taxon 18/biovar 1. Lineage C contained strains allocated to biogroup 6 from ruminants and the porcine taxon 15. The similarity between these two groups was accentuated by ribotyping. Lineage D and the single isolate in lineage E contained strains allocated to biogroups 7, 10, 8B and 8C, in addition to single strains from biogroups 6 and 9. The same strains were found in the heterogenous ribotype cluster 17. Lineage F contained strains representing the leprine taxon 20 and the ruminant (P.) granulomatis. Ribotyping indicated that the ruminant biogroup 3J was affiliated with both taxon 20 and (P.) granulomatis. PMID- 9361381 TI - Identification of Borrelia burgdorferi sensu lato tick isolates from Slovakia by PCR typing with 16S rRNA primers. AB - The first four strains of Borrelia burgdorferi isolated in Slovakia from ticks and mice were studied using monoclonal antibodies, the polymerase chain reaction (PCR) with 16S rRNA specific primers and plasmid profiles. Two tick isolates were typed as Borrelia garinii, one strain isolated from Apodemus flavicollis was found to be B. afzelii and the fourth tick isolate reacted as a mixed culture of B. garinii and B. afzelii. All four strains harboured several plasmids ranging from 6-50 kbp including a plasmid with a size of approximately 41 kbp. PMID- 9361382 TI - The isolation of Borrelia burgdorferi spirochetes from clinical material in cell line cultures. AB - It has been found that B. burgdorferi bacteria multiply in mouse fibroblasts. Mouse fibroblast of the L-929 cell line was inoculated with less than 10 up to 10(4) B. burgdorferi cells and incubated for 2-10 days at 35 degrees C in microaerophilic conditions. Within 2 days, visible growth was observed. The bacteria were present in growth medium and on/in mouse fibroblasts as revealed by the indirect immunofluorescence assay. At the same time, development of vacuolized fibroblastic giant cells was observed. Viable spirochetes were also detected in Eagle's medium from a L-929 fibroblast cell line culture, after approximately 2-5 days of incubation with blood, cerebro-spinal and synovial fluids of Lyme borreliosis patients. The bacteria were present in growth medium and on/in endothelial cells as revealed by the indirect immunofluorescence assay. The establishment of B. burgdorferi culture conditions in cell lines gives us a possibility to isolate the etiological agent of Lyme disease from patient blood, cerebrospinal and synovial fluids at different stages of infection. The high sensitivity of this procedure would be helpful in a proper identification of the infection as well as in the control of treatment effectiveness. PMID- 9361383 TI - Importance of the serovar-specific plasmid for virulence of salmonella strains in calves. AB - To evaluate the influence of serovar-specific plasmids on salmonella virulence in calves, experiments were performed involving infection, by the oral route, with mixtures of strains containing equal counts of a plasmid-carrying and a plasmid free strain of the same serovar. The concentration ratio between the plasmid carrying and the plasmid-free strain which had developed in the organs of the infected animals was used for a comparative evaluation of virulence and pathogenetic behaviour of the strains. While in the S. typhimurium strains studied, the presence of the plasmid was accompanied by a significantly increased colonization and multiplication of the agent in the host's body, examination of S. enteritidis and S. dublin revealed that the plasmid-free strains exhibited identical or even significantly higher bacterial counts than the plasmid-carrying strains in organs. The fact that plasmid-free salmonella strains with a high virulence for calves have been found demonstrates that the presence of a serovar specific plasmid is not an indispensable requirement for the development of salmonellosis in calves. PMID- 9361384 TI - Receptors on chicken erythrocytes for F42 fimbriae of Escherichia coli isolated from pigs. AB - Haemagglutination of purified F42 fimbriae was found to be inhibited by N-acetyl galactosamine. Purified F42 fimbrial adhesin reacted with distinct membrane components from chicken erythrocytes (35, 37 and 40 kDa) in immunoblot analysis, suggesting that the binding occurred to proteins or glycoproteins. PMID- 9361386 TI - Clinafloxacin (CL 960) is superior to standard therapeutics in the treatment of murine listeriosis and salmonellosis. AB - Clinafloxacin is a novel fluoroquinolone with a broad spectrum of antibacterial activity against both gramnegative and grampositive bacteria. In this work, the activity against the facultatively intracellular bacteria Listeria monocytogenes and Salmonella typhimurium was examined in vitro, in tissue culture and in animal models of infection. All strains of L. monocytogenes and S. enterica were highly susceptible against clinafloxacin, with minimal inhibitory concentrations (MICs) that were consistently lower than those for ampicillin and ciprofloxacin, respectively. Clinafloxacin was rapidly bactericidal against L. monocytogenes and S. typhimurium since 8 times the MIC killed the bacteria within 2 hours. In contrast to ampicillin and ciprofloxacin, there was a postantibiotic effect (PAE) of 2 hours with 8 x MIC on L. monocytogenes. Clinafloxacin was more effective than ampicillin and ciprofloxacin in tissue culture cells infected with S. typhimurium or L. monocytogenes. In animal models of infection, clinafloxacin was also more potent than the reference substances. In conclusion, clinafloxacin is an excellent candidate substance for the treatment of infections caused by facultatively intracellular grampositive and gramnegative bacteria. PMID- 9361385 TI - Multiplicity of the genes and plasmids conferring resistance to pristinamycin in staphylococci selected in an Algerian hospital. AB - In an Algerian hospital where pristinamycin (Pt) was extensively used for the treatment of chronic osteomyelitis and for prophylaxis in bone surgery, the prevalence of pristinamycin-resistant (PtR) staphylococci during a five-month period (20%) was higher than that among staphylococci isolated elsewhere in Algeria (4.5%). Analysis of 13 PtR staphylococci isolated in this hospital revealed a diversity of plasmids and genes conferring resistance to Pt and to related antibiotics. Most of the PtR staphylococci were unrelated: they belonged to either different taxa or types. Nevertheless, some of the unrelated staphylococci harboured structurally related plasmids carrying streptogramin resistance genes. Thus, these plasmids may have contributed to the dispersion of these genes. PMID- 9361387 TI - Selection of a strain of Clostridium argentinense producing high titers of type G botulinal toxin. AB - The strain G89HT of Clostridium argentinense obtained by culture selection of the prototype G89 strain producing high titers of type G botulinal toxin was studied. Its cultural, biochemical and toxigenic characteristics and the presence of plasmids were tested. Both strains showed similar physiological features and carried a 83 MDa plasmid. A 170 MDa plasmid was also recognized in the G89HT strain. Notably, this strain was better sporulating and showed a higher toxigenicity than the prototype G89 C. argentinense strain. These two characteristics might permit a long term storage and perhaps yield high antitoxin titres. PMID- 9361389 TI - Blastocystis hominis in animals: incidence of four serogroups. AB - In toto, 520 faecal samples from mammals, birds, reptiles, amphibians, fish, and snails were investigated (see Table 1). 91 strains of Blastocystis hominis could be isolated by culture. However, only 48 of them were suitable for axenisation. 96 percent of samples belonged to four serogroups detected in humans but two strains, one from a pig and another from a duck, could not be classified, suggesting the existence of one or two further serogroups. While humans showed mainly serogroups I and II, pigs harboured serogroups III and IV. Four serogroups were isolated from monkeys. The question whether the genus Blastocystis consists of one or more species is discussed. PMID- 9361388 TI - Streptococcal pyrogenic exotoxin A, streptolysin O, exoenzymes, serotype and biotype profiles of Streptococcus pyogenes isolates from patients with toxic shock syndrome and other severe infections. AB - The determination of protein M and T serotypes, biotypes and pyrogenic (erythrogenic) exotoxin A (SPE A), streptolysin O (SLO), streptokinase (SK), hyaluronidase (HA) and cysteine proteinase release by 212 S. pyogenes isolates from patients with severe invasive group A streptococcal (GAS) infections, among them 74 cases of streptococcal toxic shock syndrome (STSS) has been investigated. M1 or M3 serotypes were expressed by 25% of the isolates (53/212), whereas 59% (125/212) belonged to 15 other different serotypes and 16% (34/212) were untypeable. Of the 74 isolates from STSS patients, 42% (31/74) expressed M1 and to a lesser extent M3 serotypes versus 19% of the non STSS isolates (26/138). Among the ten different biotypes known, biotypes 1 and 3 were prevalent, particularly the former in the case of STSS isolates. SPE A was detectably produced by about 25% (54/212) of the strains. However, as high as 40.5% of the STSS isolates (30/74) versus 17.4% of non STSS isolates (24/138) released SPE A. Moreover, 67% of the SPE A producing strains were of serotype M1 or M3. SK and HA were released by 71% and 10% of the isolates respectively. All strains released SLO (4 to 256 HU/ml) and 85% cysteine proteinase. No relationship between toxin or enzyme titer and the type of disease or clinical origin of the strains was found. Culture supernatants of all isolates showed moderate to high lymphocyte transforming activity with index values ranging from 14.5 to 50.3 including those strains which did not release detectable amounts of SPE A suggesting that SPE C and other mitogenic factor(s) are released by the isolates investigated. PMID- 9361391 TI - Lipid profile during hormone replacement therapy: effect of different progestins? AB - Oral estrogens cause a decrease of low density lipoprotein cholesterol (LDL chol.) and, especially an increase of high density lipoprotein cholesterol (HDL chol.) levels, which both have potentially favorable effects; they also cause a triglyceride level increase, which probably has no clinical relevance except in cases with basal hypertriglyceridemia. Transdermal estradiol causes generally a minor decrease in LDL-chol. and minor increase HDL-chol. levels, with no increase or even decrease in triglyceride levels. The addition of androgenic progestins at conventionally used doses, while not interfering with LDL-chol. variations, causes a HDL-chol. decrease, which contrasts the effect of oral estrogens and completely reverses the effect of transdermal estradiol. On the contrary, the addition of a non androgenic progestin does not interfere with any of the estrogen induced lipid profile modifications. PMID- 9361390 TI - An outbreak of Streptococcus equi ssp. zooepidemicus infection of probable human origin in Wanderoos (Macaca silenus)--case report. AB - Three out of ten young to adult wanderoos (M. silenus) of a breeding colony at the Rheine Zoo died within two days from a peracute illness, characterized by salivation, vomiting, apathy and minor CNS symptoms. Streptococcus equi ssp. zooepidemicus was isolated in pure cultures from all organs of two animals investigated bacteriologically. The strains were penicillin-susceptible, and penicillin treatment of all remaining animals cured two already sick animals and prevented further cases. A volunteer worker with upper respiratory disease was suspected as source of infection; contact with equine materials and rodents could be excluded. PMID- 9361392 TI - Effect of progestins on IGF-I serum level in estrogen-treated postmenopausal women. AB - Insulin-like growth factor I (IGF-I) has a role in the whole-body anabolism and promotes both normal and abnormal cell growth in several tissues. Although IGF-I is also synthesized locally at numerous other sites, the liver does constitute the major site of its synthesis, and circulating IGF-I is mainly of hepatic derivation. The production of IGF-I is stimulated by growth hormone (GH), the secretion of which is influenced by circulating IGF-I level through a negative feed-back mechanism. Oral estrogen treatment causes a significant decrease of the IGF-I serum level, probably through a hepatocellular effect due to the first hepatic passage. Treatment with transdermal estradiol (tdE2) at the currently used doses does not cause, on average, substantial variations in the IGF-I serum level. The addition of an androgenic progestin--with strong hepatocellular actions, opposite to those of estrogen--completely reverses the IGF-I decrease induced by oral estrogens, and even causes a trend to IGF-I increase when tdE2 is used. Conversely, the addition of a non androgenic progestin, like dydrogesterone, does not cause interference with the estrogen effect. PMID- 9361393 TI - Progestins and breast cancer risk. AB - There is still no clear account on the role that progestins play in human breast cancer, and the issue continues to be debated. The effects of progestins on breast cell proliferation have been investigated in a number of different experimental systems with conflicting results. Progesterone has been reported to both stimulate and inhibit the growth of experimental mammary tumors, depending upon the dose and the experimental models. Epidemiological studies on the effect of combined hormone replacement therapy (HRT) on breast cancer risk in menopausal women are limited because the use of a progestin in addition to estrogens was not widely adopted until 10 years ago. Taking meta-analysis into account estrogen progestin use did conclude that there is not an excess risk in combined HRT users. Epidemiological studies have provided conflicting results, ranging from a protective effect to a deleterious effect of progestin addition on breast cancer risk. Progestins include a large family of molecules characterised by different binding capacities to androgen receptors. This implies that they should be considered as distinct yet related, therapeutic agents. The use of different progestins may account for the controversial results obtained in studies conducted in different geographic areas. PMID- 9361394 TI - Oestrogens, progestins and breast proliferation. AB - Aspects of the relation between endogenous and exogenous female sex steroids and the normal and malignant growth of the human breast are described. Starting points are the natural history of tumours, distinguishing between initiation, promotion and progression, and the risk factors for breast cancer as identified by epidemiology. The role of sex steroid hormones during the pubertal growth of the breast, the importance of the time between first growth and first pregnancy and the effects of pregnancy on the composition of the lobular structures in the human breast are discussed. The background of the suggested role of growth promoting effects of locally produced active oestrogens, especially in postmenopausal women, is given. From the evidence obtained from biochemical studies on the importance of the oestrogen production by the breast itself a mechanism is suggested to explain the possible lack of effects of exogenous oestrogens on the incidence of breast cancer. PMID- 9361395 TI - Role, control and expression of estrone sulfatase and 17 beta-hydroxysteroid dehydrogenase activities in human breast cancer. AB - Breast cancer tissue contains the enzymes necessary for local synthesis of estradiol (E2) and it was demonstrated that, despite the presence of the sulfatase and its messenger in hormone-dependent and hormone-independent breast cancer cells, this enzyme operates particularly in hormone-dependent cells. Different progestins: Nomegestrol acetate, Promegestone, Tibolone (Org OD14) and its metabolites (Org-OM38, Org 4098 and Org 30126), as well as Danazol, can block the conversion of estrone sulfate to E2 very strongly in hormone-dependent breast cancer cells. The last step in the formation of E2 is the conversion of estrone (E1) to estrogen by the action of 17 beta-hydroxysteroid dehydrogenase. This activity is preferentially in the reductive direction (formation of E2) in hormone-dependent cells, but oxidative (E2-->E1) in hormone-independent cells. Using intact hormone-dependent cells, it was observed that Nomegestrol acetate. Promegestone as well as Danazol, can block the conversion of E1 to E2. Clinical trials of these "anti-enzyme" substances in breast cancer patients could be the next step to investigate new therapeutic possibilities for this disease. PMID- 9361396 TI - Progestins and bone. AB - Since the introduction of hormone replacement therapy which combines administration of oestrogens with cyclic or continuous administration of progestins, attention has been paid to the possible modulating effect of the progestin on the beneficial effects of the oestrogens. In this review data regarding the effects of progestins and of oestrogen/progestin combinations on bone in women have been summarized. The conclusion is that there is no evidence for a negative influence of progestins on the beneficial effects of oestrogens on the bone. To the contrary, progestins seem to have additional bone sparing properties because they are capable of stimulating the formation of bone, but the exact mechanism is still under discussion. PMID- 9361397 TI - Vaginal vs. transabdominal ultrasonography in the evaluation of female urinary tract anatomy, stress urinary incontinence and pelvic organs static disturbances. AB - In this multicentric prospective and randomized study we compared the results obtained by application of a vaginal ultrasound probe in the vaginal introitus to those obtained by the transabdominal one. 66 examined patients were separated in five groups according to the history and gynaecological investigation. Stress urinary incontinence was urodynamically proved. After analysing the results obtained by those methods we conclude that the transabdominal method gives more useful data for stress urinary incontinence and pelvic organs static disturbances (SUI and POSD) diagnosing, but the introital application of the vaginal probe is also very useful for analysing the urethrovesical junction (UVJ) position comparing of its mobility in rest and maximal strain positions. We have found that a posterior vesicourethral angle less than 75 degrees measured by the endovaginal probe was a reliable proof of the cystocele. The results were comparable to clinical status and transabdominal sonography of the moderately full bladder. Transabdominal and endovaginal methods give rather complementary than competition data which are very useful in diagnosing of the POSD, SUI and UVJ position and degree of its mobility. For that reason both techniques may precisely discover and document the presence of anatomic stress urinary incontinence causative defects aiding in the selection of patients suitable for operative therapy of stress urinary incontinence and for their postoperative follow-up. PMID- 9361398 TI - A novel competence gene, comP, is essential for natural transformation of Acinetobacter sp. strain BD413. AB - Acinetobacter sp. strain BD413 (= ATCC 33305), a nutritionally versatile bacterium, has an extremely efficient natural transformation system. Here we describe the generation of eight transformation-affected mutants of Acinetobacter sp. strain BD413 by insertional mutagenesis. These mutants were found by Southern blot analysis and complementation studies to result from single nptII marker insertions at different chromosomal loci. DNA binding and uptake studies with one mutant, T205, revealed that the transformation deficiency of this mutant results from a complete lack of DNA binding and, therefore, uptake activity. A novel competence gene essential for natural transformation, named comP, was cloned by complementation of mutant T205. The nucleotide sequence of comP was determined, and its deduced 15-kDa polypeptide displays significant similarities to type IV pilins. Analysis of the ultrastructure of a transformation-deficient comP mutant and the transformation-competent wild-type strain revealed that both are covered with bundle-forming thin fimbriae (3 to 4 nm in diameter) and individual thick fimbriae (6 nm in diameter). These results provide evidence that the pilinlike ComP is unrelated to the piluslike structures of strain BD413. Taking all data into account, we propose that ComP functions as a major subunit of an organelle acting as a channel or pore mediating DNA binding and/or uptake in Acinetobacter sp. strain BD413. PMID- 9361399 TI - Effects of lactobacilli on yeast-catalyzed ethanol fermentations. AB - Normal-gravity (22 to 24 degrees Plato) wheat mashes were inoculated with five industrially important strains of lactobacilli at approximately 10(5), approximately 10(6), approximately 10(7), approximately 10(8), and approximately 10(9) CFU/ml in order to study the effects of the lactobacilli on yeast growth and ethanol productivity. Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus #3, Lactobacillus rhamnosus, and Lactobacillus fermentum were used. Controls with yeast cells but no bacterial inoculation and additional treatments with bacteria alone inoculated at approximately 10(7) CFU/ml of mash were included. Decreased ethanol yields were due to the diversion of carbohydrates for bacterial growth and the production of lactic acid. As higher numbers of the bacteria were produced (depending on the strain), 1 to 1.5% (wt/vol) lactic acid resulted in the case of homofermentative organisms. L. fermentum, a heterofermentative organism, produced only 0.5% (wt/vol) lactic acid. When L. plantarum, L. rhamnosus, and L. fermentum were inoculated at approximately 10(6) CFU/ml, an approximately 2% decrease in the final ethanol concentration was observed. Smaller initial numbers (only 10(5) CFU/ml) of L. paracasei or Lactobacillus #3 were sufficient to cause more than 2% decreases in the final ethanol concentrations measured compared to the control. Such effects after an inoculation of only 10(5) CFU/ml may have been due to the higher tolerance to ethanol of the latter two bacteria, to the more rapid adaptation (shorter lag phase) of these two industrial organisms to fermentation conditions, and/or to their more rapid growth and metabolism. When up to 10(9) CFU of bacteria/ml was present in mash, approximately 3.8 to 7.6% reductions in ethanol concentration occurred depending on the strain. Production of lactic acid and a suspected competition with yeast cells for essential growth factors in the fermenting medium were the major reasons for reductions in yeast growth and final ethanol yield when lactic acid bacteria were present. PMID- 9361400 TI - Isolation of new bacterial species from drinking water biofilms and proof of their in situ dominance with highly specific 16S rRNA probes. AB - A polyphasic approach involving cultivation, direct viable counts, rRNA-based phylogenetic classification, and in situ probing was applied for the characterization of the dominant microbial population in a municipal drinking water distribution system. A total of 234 bacterial strains cultivated on R2A medium were screened for bacteria affiliated with the in situ dominating beta subclass of Proteobacteria. The isolates were grouped according to common features of their cell and colony morphologies, and eight representative strains were used for 16S rRNA sequencing and the development of a suite of strain specific oligonucleotide probes. Phylogenetic analysis indicated that all of the isolates were hitherto unknown bacteria. Three of them, strains B4, B6, and B8, formed a separate cluster of closely related organisms within the beta 1 subclass of Proteobacteria. In situ probing revealed that (i) 67 to 72% of total bacteria, corresponding to more than 80% of beta-subclass bacteria, could be encompassed with the strain-specific probes and (ii) the dominating bacterial species were culturable on R2A medium. Additionally, two-thirds of the autochthonous drinking water population could be shown to be in a viable but nonculturable (VBNC) state by using a direct viable count approach. The comparison of isolation frequencies with the in situ abundances of the eight investigated strains revealed differences in their culturability, indicating variable ratios of culturable to VBNC cells among the strains. The further characterization of biofilms throughout the distribution network demonstrated strains B6 and B8 to be dominant bacterial strains in groundwater and distribution system biofilms. The other strains could be found at various frequencies in the different parts of the distribution system; several strains appeared exclusively in drinking water biofilms obtained from a house installation system. PMID- 9361401 TI - Effects of elevated dissolved CO2 levels on batch and continuous cultures of Aspergillus niger A60: an evaluation of experimental methods. AB - The effects of elevated levels of dissolved carbon dioxide (dCO2), produced by gassing with CO2-enriched gas mixtures, upon an industrial strain of Aspergillus niger (strain A60) producing citrate and gluconate were quantitatively assessed. Particular attention was paid to the reliability and accuracy of the steam sterilizable dCO2 probe, especially in the presence of high concentrations of potentially interfering acidic species. The response of the organism to elevated dCO2 levels was assessed by using both batch and chemostat cultures, and the sensitivity of the organism in different growth phases (lag, exponential, and stationary) was examined. Chemostat cultures showed markedly less inhibition (in terms of biomass and organic acid synthesis) than did batch cultures. Studies in batch culture indicated that lag-phase cultures were especially sensitive to elevated dCO2 levels. Overall, the results of this study indicate that previous experimental methods used to examine dCO2 effects in submerged cultures (continuous CO2-enriched gassing of batch cultures from time zero) have been inappropriate and have led to systematic overestimation of the inhibitory effects of dCO2 on mycelial organisms. PMID- 9361402 TI - Purification and characterization of staphylococcin BacR1, a broad-spectrum bacteriocin. AB - The bacteriocin BacR1 was purified from culture supernatant of Staphylococcus aureus UT0007 by sequential ammonium sulfate precipitation, cation-exchange chromatography, and C4 reverse-phase chromatography steps. Mass spectrographic analysis indicated that the purified peptide has a molecular mass of 3,338 Da. It is resistant to environmental conditions, retaining full biological activity after exposure to pH extremes (pHs 3 to 11), heating at 95 degrees C for 15 min, and exposure to strong chaotropic agents. BacR1 was destroyed with a complete loss of biological activity after digestion with trypsin and proteinase K. Amino acid sequence analysis revealed a high concentration of Asx, Gly, and Pro residues and a high proportion of hydrophobic amino acids. The peptide is bactericidal and kills in a dose-dependent manner, but it does not lyse log-phase cells of Corynebacterium renale, the routine indicator organism for bacteriocin assay. A specific receptor for binding was detected on sensitive cells but not on insensitive cells. Competition assays showed that UV-inactivated cells could protect susceptible cells from antibacterial action. A partial inhibitory spectrum revealed that organisms from the following genera are susceptible: Staphylococcus, Streptococcus, Corynebacterium, Haemophilus, Bordetella, Moraxella, Pasteurella, Neisseria, and Bacillus. PMID- 9361403 TI - Conversion of beta-methylbutyric acid to beta-hydroxy-beta-methylbutyric acid by Galactomyces reessii. AB - beta-Hydroxy-beta-methylbutyric acid (HMB) has been shown to increase strength and lean mass gains in humans undergoing resistance-exercise training. HMB is currently marketed as a calcium salt of HMB, and thus, environmentally sound and inexpensive methods of manufacture are being sought. This study investigates the microbial conversion of beta-methylbutyric acid (MBA) to HMB by cultures of Galactomyces reessii. Optimal concentrations of MBA were in the range of 5 to 20 g/liter for HMB production. Preliminary shake flask experiments indicated that HMB yields were sensitive to dissolved oxygen levels and that cell growth decreased significantly as MBA concentrations increased. Degradation of HMB was faster at acidic pH, and pH 7.0 was optimal for HMB production. Resting cells obtained from media without MBA could efficiently convert MBA to HMB. Thus, a two step, fed-batch fermentation procedure in which biomass was first produced, followed by coaddition of MBA and glucose, while dissolved oxygen was maintained at 20% of saturation, was designed. A maximum HMB concentration of 38 g/liter was obtained after 136 h, and the molar conversion yield was more than 0.50 mol of HMB/mol of MBA during the fermentation. PMID- 9361404 TI - Visualization of specific gene expression in individual Salmonella typhimurium cells by in situ PCR. AB - An in situ PCR protocol by which we can monitor the presence or absence of lac mRNA in individual cells of a Salmonella typhimurium F' lac+ strain has been developed. In this protocol, fixed cells are permeabilized with lysozyme and subjected to a seminested reverse transcriptase PCR using reporter molecule labeled primers, and subsequently, intracellular reporter molecules are detected microscopically at the individual-cell level by use of a horseradish peroxidase conjugated antifluorescein antibody assay. In order to determine the sensitivity of the in situ PCR assay, the ability to detect lac mRNA in suboptimally isopropyl-beta-D-thiogalactopyranoside-induced cells was investigated. By use of a single-cell beta-galactosidase assay, it was confirmed that homogeneous suboptimally induced cultures of S. typhimurium F' lacY cells could be established, and the number of functional lac mRNAs in individual cells was estimated from standard population level beta-galactosidase assays. Cells estimated to contain a single lac mRNA were detected as containing lac mRNA by the in situ PCR method. Conclusively, we demonstrate the potential of in situ PCR for detection of even poorly expressed mRNA in individual bacterial cells. PMID- 9361405 TI - Recovery of culturability of an HOCl-stressed population of Escherichia coli after incubation in phosphate buffer: resuscitation or regrowth? AB - An Escherichia coli population harvested in exponential phase at about 10(8) cells/ml was treated in phosphate buffer with HOCl at concentrations ranging from 0.4 to 1 mg/liter (7.7 to 19 microM). The HOCl stress resulted in the appearance of three cell subpopulations: a majority of dead (nonrespiring) cells, a few culturable cells (10(2) to 10(4)), and about 10(7) viable but nonculturable cells. In the absence of any added exogenous nutrient, a culturable population could be recovered after 1 day of incubation in phosphate buffer, and such a population would reach a cell density close to 10% of the initial density of the stressed population, whatever the initial number of survivors. When a small number of untreated cells were mixed with the stressed population, growth of the untreated cells was observed, demonstrating that damaged cells provided nutrients. Similarly, a filtrate and a disrupted-cell filtrate of the stressed population supported growth of untreated cells with the same efficiency. The number of CFU (untreated or stressed) at plateau phase depended on the initial density of the stressed cells. Taken together, these results suggest that recovery in phosphate buffer of an HOCl-stressed population is in large part due to growth of a few culturable cells at the expense of damaged cells. However, comparison of the growth rates of the stressed culturable population and of untreated bacteria growing in filtrate showed significantly faster growth of the stressed cells, a fact not fully compatible with the hypothesis that recovery is only the simple growth of survivors. We suggest, therefore, that in addition to growth of the few culturable stressed cells, there is repair and growth of some mildly injured viable but nonculturable cells. PMID- 9361406 TI - Intracellular pH is a major factor in the induction of tolerance to acid and other stresses in Lactococcus lactis. AB - This study demonstrates that exposure of log-phase Lactococcus lactis subsp. cremoris 712 cells to mildly acid conditions induces resistance to normally lethal intensities of environmental stresses such as acid, heat, NaCl, H2O2, and ethanol. The intracellular pH (pHi) played a major role in the induction of this multistress resistance response. The pHi was dependent on the extracellular pH (pHo) and on the specific acid used to reduce the pHo. When resuspended in fresh medium, cells were able to maintain a pH gradient even at pHo values that resulted in cell death. Induction of an acid tolerance response (ATR) coincided with an increase in the ability of cells to resist change to an unfavorable pHi; nevertheless, a more favorable pHi was not the sole reason for the increased survival at acid pHo. Cells with an induced ATR survived exposure to a lethal pHo much better than did uninduced cells with a pHi identical to that of the induced cells. Survival following lethal acid shock was dependent on the pHi during induction of the ATR, and the highest survival was observed following induction at a pHi of 5.9, which was the lowest pHi at which growth occurred. Increased acid tolerance and the ability to maintain a higher pHi during lethal acid stress were not acquired if protein synthesis was inhibited by chloramphenicol during adaptation. PMID- 9361407 TI - Biodegradation of the gasoline oxygenates methyl tert-butyl ether, ethyl tert butyl ether, and tert-amyl methyl ether by propane-oxidizing bacteria. AB - Several propane-oxidizing bacteria were tested for their ability to degrade gasoline oxygenates, including methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). Both a laboratory strain and natural isolates were able to degrade each compound after growth on propane. When propane-grown strain ENV425 was incubated with 20 mg of uniformly labeled [14C]MTBE per liter, the strain converted > 60% of the added MTBE to 14CO2 in < 30 h. The initial oxidation of MTBE and ETBE resulted in the production of nearly stoichiometric amounts of tert-butyl alcohol (TBA), while the initial oxidation of TAME resulted in the production of tert-amyl alcohol. The methoxy methyl group of MTBE was oxidized to formaldehyde and ultimately to CO2. TBA was further oxidized to 2-methyl-2-hydroxy-1-propanol and then 2-hydroxy isobutyric acid; however, neither of these degradation products was an effective growth substrate for the propane oxidizers. Analysis of cell extracts of ENV425 and experiments with enzyme inhibitors implicated a soluble P-450 enzyme in the oxidation of both MTBE and TBA. MTBE was oxidized to TBA by camphor-grown Pseudomonas putida CAM, which produces the well-characterized P-450cam, but not by Rhodococcus rhodochrous 116, which produces two P-450 enzymes. Rates of MTBE degradation by propane-oxidizing strains ranged from 3.9 to 9.2 nmol/min/mg of cell protein at 28 degrees C, whereas TBA was oxidized at a rate of only 1.8 to 2.4 nmol/min/mg of cell protein at the same temperature. PMID- 9361408 TI - Flow sorting of microorganisms for molecular analysis. AB - Not only classical cultivation-based methods but also the new molecular approaches may result in incomplete and selective information on the natural diversity of microbial communities. Flow sorting of microorganisms from environmental samples allows the deliberate selection of cell populations of interest from highly diverse systems for molecular analysis. Several cellular parameters that can be measured by flow cytometry are useful as sort criteria. Here, we report sorting of bacteria from activated sludge, lake water, and lake sediment according to differences in light scattering, DNA content, and/or affiliation to certain phylogenetic groups as assessed by fluorescein-labeled, rRNA-targeted oligonucleotide probes. Microscopy of the sorted cells showed that populations of originally low abundance could be strongly enriched by flow sorting (up to 280-fold), depending on the original abundance of the cells of interest and the type of sample sorted. The purity of the cells of interest could be further increased by repeated sorting, but this increase was limited by cell aggregation in the case of activated-sludge samples. It was possible to amplify almost full-length 16S ribosomal DNA (rDNA) fragments from sorted microbial cells by PCR, even after fixation with paraformaldehyde and in situ hybridization. Dot blot hybridization and sequencing demonstrated that most of the amplified rDNA originated from those cells that had been selected for by flow sorting. Comparative analysis of 16S rDNA sequences revealed previously unknown species of magnetotactic or activated-sludge bacteria. PMID- 9361409 TI - Detection of enterotoxigenic Clostridium perfringens in food and fecal samples with a duplex PCR and the slide latex agglutination test. AB - A duplex PCR procedure was evaluated for the detection of Clostridium perfringens in food and biological samples and for the identification of enterotoxigenic strains. This method uses two sets of primers which amplify in the same reaction two different DNA fragments simultaneously: the 283-bp C. perfringens phospholipase C gene fragment and the 426-bp enterotoxin gene fragment. Internal primers within the two primer sets confirmed the specificity of the method by DNA DNA hybridization with the PCR products. No cross-reaction was observed with other Clostridium species or with other bacteria routinely found in food. The detection level was approximately 10(5) C. perfringens cells per g of stool or food sample. When overnight enrichment culture was used, 10 C. perfringens cells per g was detected in 57 artificially contaminated food samples. The duplex PCR is a rapid, sensitive, and reliable method for the detection and identification of enterotoxigenic C. perfringens strains in food samples. A slide latex agglutination test was also evaluated as a rapid, simple technique for the detection of C. perfringens enterotoxin in stool samples. PMID- 9361410 TI - Numerical dominance of a group of marine bacteria in the alpha-subclass of the class Proteobacteria in coastal seawater. AB - A cluster of marine bacteria within the alpha-3 subclass of the class Proteobacteria accounted for up to 28% of the 16S ribosomal DNA (rDNA) sequences in seawater samples from the coast of the southeastern United States. Two independent oligonucleotide probes targeting 16S rDNA of this "marine alpha" cluster indicate that the group dominates bacterioplankton communities in estuarine and nearshore regions of the southeastern U.S. coast. Marine alpha bacteria decline predictably in abundance with decreasing salinity along estuarine transsects and are not detectable in low-salinity (5%) or freshwater samples. Sequences of 16S rDNA obtained from seawater by PCR with one group specific oligonucleotide as a primer confirm that the oligonucleotide targets only members of this phylogenetic cluster. Likewise, sequences of 16S rDNA obtained from seawater by PCR with several different pairs of nonspecific primers show an unusually high abundance of marine alpha sequences (52 to 84%) among the clones, which possibly indicates a PCR bias toward the group. Members of the marine alpha group were readily cultured from coastal seawater, accounting for 40% of the colonies isolated on low-nutrient marine agar, based on hybridizations with the group-specific 16S rDNA probe and on sequence analysis. This is the first description of a numerically dominant cluster of coastal bacteria, identified by molecular techniques, that can be readily cultured and studied in the laboratory. PMID- 9361411 TI - Characterization of the lacticin 481 operon: the Lactococcus lactis genes lctF, lctE, and lctG encode a putative ABC transporter involved in bacteriocin immunity. AB - The lantibiotic lacticin 481 is a bacteriocin produced by Lactococcus lactis strains. The genetic determinants of lacticin 481 production are organized as an operon encoded by a 70-kb plasmid. We previously reported the first three genes of this operon, lctA, lctM, and lctT, which are involved in the bacteriocin biosynthesis and export (A. Rince, A. Dufour, S. Le Pogam, D. Thuault, C. M. Bourgeois, and J.-P. Le Pennec, Appl. Environ. Microbiol. 60:1652-1657, 1994). The operon contains three additional open reading frames: lctF, lctE, and lctG. The hydrophobicity profiles and sequence similarities strongly suggest that the three gene products associate to form an ABC transporter. When the three genes were coexpressed into a lacticin 481-sensitive L. lactis strain, the strain became resistant to the bacteriocin. This protection could not be obtained when any of the three genes was deleted, confirming that lctF, lctE, and lctG are all necessary to provide immunity to lacticin 481. The quantification of the levels of immunity showed that lctF, lctE, and lctG could account for at least 6% and up to 100% of the immunity of the wild-type lacticin 481 producer strain, depending on the gene expression regulation. The lacticin 481 biosynthesis and immunity systems are discussed and compared to other lantibiotic systems. PMID- 9361412 TI - Evidence for signaling between the phytopathogenic fungus Pythium ultimum and Pseudomonas fluorescens F113: P. ultimum represses the expression of genes in P. fluorescens F113, resulting in altered ecological fitness. AB - There is increasing evidence that communication between members of the same species, as well as members of different species, is important for the survival of microorganisms in diverse ecological niches, such as the rhizosphere. To investigate whether the phytopathogen Pythium ultimum could alter gene expression in the biocontrol strain Pseudomonas fluorescens F113, which protects the roots of sugar beet from the fungus, a screening system was developed to detect differential expression of bacterial genes in the presence of P. ultimum. The transposon Tn5, containing a promoterless lacZ reporter gene, was used to generate a library of transcriptional gene fusions in P. fluorescens F113. By this screening procedure, five P. fluorescens F113 gene clusters were identified and shown to be repressed in the presence of P. ultimum. The ecological fitness of three of the five reporter mutants in the rhizosphere of seed-inoculated sugar beet was lower than that of the wild type. Furthermore, all five mutants were impaired in their ability to subsequently colonize the rhizosphere of uninoculated sugar beet sown repeatedly in the same soil. With the exception of reporter mutant SF10, which was impaired in nitrogen metabolism, the reporter mutants had growth requirements and biocontrol abilities similar to those of the wild type. This is the first reported case of a fungus repressing the expressing of bacterial genes. PMID- 9361413 TI - Effects of dissolved organic carbon and salinity on bioavailability of mercury. AB - Hypotheses that dissolved organic carbon (DOC) and electrochemical charge affect the rate of methylmercury [CH3Hg(I)] synthesis by modulating the availability of ionic mercury [Hg(II)] to bacteria were tested by using a mer-lux bioindicator (O. Selifonova, R. Burlage, and T. Barkay, Appl. Environ. Microbiol. 59:3083 3090, 1993). A decline in Hg(II)-dependent light production was observed in the presence of increasing concentrations of DOC, and this decline was more pronounced at pH 7 than at pH 5, suggesting that DOC is a factor controlling the bioavailability of Hg(II). A thermodynamic model (MINTEQA2) was used to select assay conditions that clearly distinguished among various Hg(II) species. By using this approach, it was shown that negatively charged forms of mercuric chloride (HgCl3-/HgCl(4)2-) induced less light production than the electrochemically neutral form (HgCl2), and no difference was observed between the two neutral forms, HgCl2 and Hg(OH)2. These results suggest that the negative charge of Hg(II) species reduces their availability to bacteria and may be one reason why accumulation of CH3Hg(I) is more often reported to occur in freshwater than in estuarine and marine biota. PMID- 9361414 TI - Degradation of the fluoroquinolone enrofloxacin by the brown rot fungus Gloeophyllum striatum: identification of metabolites. AB - The degradation of enrofloxacin, a fluoroquinolone antibacterial drug used in veterinary medicine, was investigated with the brown rot fungus Gloeophyllum striatum. After 8 weeks, mycelia suspended in a defined liquid medium had produced 27.3, 18.5, and 6.7% 14CO2 from [14C]enrofloxacin labeled either at position C-2, at position C-4, or in the piperazinyl moiety, respectively. Enrofloxacin, applied at 10 ppm, was transformed into metabolites already after about 1 week. The most stable intermediates present in 2-day-old supernatants were analyzed by high-performance liquid chromatography combined with electrospray ionization mass spectrometry. Eight of 11 proposed molecular structures could be confirmed by 1H nuclear magnetic resonance spectroscopy or by cochromatography with reference compounds. We identified (i) 3-, 6-, and 8 hydroxylated congeners of enrofloxacin, which have no or only very little residual antibacterial activity; (ii) 5,6- (or 6,8-), 5,8-, and 7,8 dihydroxylated congeners, which were prone to autoxidative transformation; (iii) an isatin-type compound as well as an anthranilic acid derivative, directly demonstrating cleavage of the heterocyclic core of enrofloxacin; and (iv) 1 ethylpiperazine, the 7-amino congener, and desethylene-enrofloxacin, representing both elimination and degradation of the piperazinyl moiety. The pattern of metabolites implies four principle routes of degradation which might be simultaneously employed. Each route, initiated by either oxidative decarboxylation, defluorination, hydroxylation at C-8, or oxidation of the piperazinyl moiety, may reflect an initial attack by hydroxyl radicals at a different site of the drug. During chemical degradation of [4-14C]enrofloxacin with Fenton's reagent, five confirmatory metabolites, contained in groups i and iv, were identified. These findings provide new evidence in support of the hypothesis that brown rot fungi may be capable of producing hydroxyl radicals, which could be utilized to degrade wood and certain xenobiotics. PMID- 9361415 TI - Indigo formation by microorganisms expressing styrene monooxygenase activity. AB - The transformation of indole to indigo by microorganisms expressing styrene monooxygenase (SMO) has been studied. Styrene and indole are structurally very similar, and thus we looked at a variety of styrene-degrading strains for indole transformation to indigo. Two strains, Pseudomonas putida S12 and CA-3, gave a blue color on solid media when grown in the presence of indole. Indole induces its own transformation on solid media but is a poor inducer in liquid media. Styrene is the best inducer of indole transformation in both strains. Arginine represses styrene consumption and indigo formation rates in P. putida S12 compared to phenylacetic acid-grown cells, while the opposite effect is seen for P. putida CA-3. Characterization of an SMO- and styrene oxide isomerase (SOI) negative transposon mutant of P. putida CA-3 and an SOI-negative N-methyl-N' nitro-N-nitrosoguanidine mutant of P. putida S12 reveals the involvement of both SMO and SOI in indole transformation to indigo. Both strains stoichiometrically produce high-purity indigo from indole. PMID- 9361416 TI - cis-trans isomerization of unsaturated fatty acids: cloning and sequencing of the cti gene from Pseudomonas putida P8. AB - Transposon mutants of Pseudomonas putida P8 were generated by applying a mini-Tn5 mutagenesis system. The mutants obtained were checked for their ability to tolerate increased temperatures and elevated phenol concentrations. Approximately 5,800 transposon mutants were used to generate a pool of 600 temperature sensitive strains; one of these strains was identified as being damaged in its ability to perform cis-trans isomerization of fatty acids. A gene library of P. putida P8 was constructed and screened by using as a probe sequences immediately adjacent to the mini-Tn5 insertion. A DNA fragment that complemented the mutation was isolated and cloned. The corresponding gene, termed cti, is located close to the methionine synthase locus (metH) in P. putida P8. A cti-carrying fragment integrated into a plasmid also conferred the ability for cis-trans isomerization to Escherichia coli; the cti gene was completely sequenced, and the amino acid sequence was deduced. PMID- 9361417 TI - Synechococcus diversity in the California current as seen by RNA polymerase (rpoC1) gene sequences of isolated strains. AB - Because they are ubiquitous in a range of aquatic environments and culture methods are relatively advanced, cyanobacteria may be useful models for understanding the extent of evolutionary adaptation of prokaryotes in general to environmental gradients. The roles of environmental variables such as light and nutrients in influencing cyanobacterial genetic diversity are still poorly characterized, however. In this study, a total of 15 Synechococcus strains were isolated from the oligotrophic edge of the California Current from two depths (5 and 95 m) with large differences in light intensity, light quality, and nutrient concentrations. RNA polymerase gene (rpoC1) fragment sequences of the strains revealed two major genetic lineages, distinct from other marine or freshwater cyanobacterial isolates or groups seen in shotgun-cloned sequences from the oligotrophic Atlantic Ocean. The California Current low-phycourobilin (CCLPUB) group represented by six isolates in a single lineage was less diverse than the California Current high-phycourobilin (CCHPUB) group with nine isolates in three relatively divergent lineages. The former was found to be the closest known genetic group to Prochlorococcus spp., a chlorophyll b-containing cyanobacterial group. Having an isolate from this group will be valuable for looking at the molecular changes necessary for the transition from the use of phycobiliproteins to chlorophyll b as light-harvesting pigments. Both of the CCHPUB and CCLPUB groups included strains obtained from surface (5 m) and deep (95 m) samples. Thus, contrary to expectations, there was no clear correlation between sampling depth and isolation of genetic groups, despite the large environmental gradients present. To our knowledge, this is the first demonstration with isolates that genetically divergent Synechococcus groups coexist in the same seawater sample. PMID- 9361418 TI - Stabilization of apoglobin by low temperature increases yield of soluble recombinant hemoglobin in Escherichia coli. AB - Accumulation of soluble recombinant hemoglobin (rHb1.1) in Escherichia coli requires proper protein folding, prosthetic group (heme) addition, and subunit assembly. This served as a new model system for the study of the effects of temperature, protein synthesis rates, and protein accumulation rates on protein solubility in E. coli. Fermentation expression of rHb1.1 at 30 degrees C from cultures containing a medium or high globin gene dosage (pBR-based or pUC-based plasmids with rHb1.1 genes under the control of the tac promoter) was compared. A medium gene dosage resulted in rHb1.1 accumulating to approximately 7% of the soluble cell protein, of which 78% was soluble. A high globin gene dosage resulted in a > or = 3-fold increase in total globin to 23 to 24% of the soluble cell protein, but 70% was insoluble. Accumulation of insoluble rHb1.1 began immediately upon induction. The proportion of rHb1.1 from the high globin gene dosage that accumulated as insoluble globin was affected by reducing (i) the inducer concentration and (ii) the temperature. Reducing the inducer concentration reduced globin synthesis up to eightfold but increased the proportion of soluble rHb1.1 to 93%. In contrast, total globin protein synthesis was barely affected by reducing the temperature from 30 to 26 degrees C, while soluble globin accumulation increased > 2-fold to approximately 15% of the soluble cell protein. The contrast between the effects of reducing rates of protein synthesis and accumulation and those of reducing temperature suggests that lower temperature stabilizes one or more folding intermediates. We propose a simplified physical model which integrates protein synthesis, folding, and heme association. This model shows that temperature-dependent apoglobin stability is the most critical factor in soluble rHb1.1 accumulation. PMID- 9361419 TI - Biochemical and genetic characterization of enterocin P, a novel sec-dependent bacteriocin from Enterococcus faecium P13 with a broad antimicrobial spectrum. AB - Enterocin P is a new bacteriocin produced by Enterococcus faecium P13 isolated from a Spanish dry-fermented sausage. Enterocin P inhibited most of tested spoilage and food-borne gram-positive pathogenic bacteria, such as Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens, and Clostridium botulinum. Enterocin P is produced during growth in MRS broth from 16 to 45 degrees C; it is heat resistant (60 min at 100 degrees C; 15 min at 121 degrees C) and can withstand exposure to pH between 2.0 and 11.0, freeze-thawing, lyophilization, and long-term storage at 4 and -20 degrees C. The bacteriocin was purified to homogeneity by ammonium sulfate precipitation, gel filtration, cation exchange, hydrophobic-interaction, and reverse-phase liquid chromatography. The sequence of 43 amino acids of the N terminus was obtained by Edman degradation. DNA sequencing analysis of a 755-bp region revealed the presence of two consecutive open reading frames (ORFs). The first ORF encodes a 71-amino-acid protein containing a hydrophobic N-terminal sec-dependent leader sequence of 27 amino acids followed by the amino acid sequence corresponding to the purified and sequenced enterocin P. The bacteriocin is apparently synthesized as a prepeptide that is cleaved immediately after the Val-Asp-Ala residues (positions -3 to -1), resulting in the mature bacteriocin consisting of 44 amino acids, and with a theoretical molecular weight of 4,493. A second ORF, encoding a putative immunity protein composed of 88 amino acids with a calculated molecular weight of 9,886, was found immediately downstream of the enterocin P structural gene. Enterocin P shows a strong antilisterial activity and has the consensus sequence found in the pediocin-like bacteriocins; however, enterocin P is processed and secreted by the sec-dependent pathway. PMID- 9361420 TI - Identification of N2-fixing plant- and fungus-associated Azoarcus species by PCR based genomic fingerprints. AB - Most species of the diazotrophic Proteobacteria Azoarcus spp. occur in association with grass roots, while A. tolulyticus and A. evansii are soil bacteria not associated with a plant host. To facilitate species identification and strain comparison, we developed a protocol for PCR-generated genomic fingerprints, using an automated sequencer for fragment analysis. Commonly used primers targeted to REP (repetitive extragenic palindromic) and ERIC (enterobacterial repetitive intergenic consensus) sequence elements failed to amplify fragments from the two species tested. In contrast, the BOX-PCR assay (targeted to repetitive intergenic sequence elements of Streptococcus) yielded species-specific genomic fingerprints with some strain-specific differences. PCR profiles of an additional PCR assay using primers targeted to tRNA genes (tDNA PCR, for tRNA(IIe)) were more discriminative, allowing differentiation at species specific (for two species) or infraspecies-specific level. Our protocol of several consecutive PCR assays consisted of 16S ribosomal DNA (rDNA)-targeted, genus-specific PCR followed by BOX- and tDNA-PCR; it enabled us to assign new diazotrophic isolates originating from fungal resting stages (sclerotia) to known species of Azoarcus. The assignment was confirmed by phylogenetic analysis of 16S rDNA sequences. Additionally, the phylogenetic distances and the lack of monophyly suggested emendment of the genus Azoarcus: the unnamed species Azoarcus groups C and D and a new group (E) of Azoarcus, which was detected in association with fungi, are likely to have the taxonomic rank of three different genera. According to its small subunit rRNA, the sclerotium-forming basidiomycete was related to the Ustilagomycetes, facultatively biotrophic parasites of plants. Since they occurred in a field which was under cultivation with rice and wheat, these fungi might serve as a niche for survival for Azoarcus in the soil and as a source for reinfection of plants. PMID- 9361422 TI - Glycogen biosynthesis via UDP-glucose in the ruminal bacterium Prevotella bryantii B1(4). AB - Prevotella bryantii is an important amylolytic bacterium in the rumen that produces considerable amounts of glycogen when it is grown on maltose. Radiolabel studies indicated that glucose-1-phosphate was converted to UDP-glucose, and this latter intermediate served as the immediate precursor for glycogen synthesis. High levels of UDP-glucose pyrophosphorylase activities (> 1,492 nmol/min/mg of protein) were detected in cells grown on maltose, cellobiose, glucose, or sucrose, and activity was greatly stimulated (by approximately 60-fold) by the addition of fructose-1,6-bis phosphate (half-maximal activation concentration was 240 microM). However, ADP-glucose pyrophosphorylase activity was not detected in any of the cultures. Glycogen synthase activity in maltose-grown cultures (48 nmol/min/mg of protein) was higher than that in cellobiose-, sucrose-, and glucose-grown cultures (< 26 nmol/min/mg of protein). This is the first report of a bacterium that exclusively uses UDP-glucose to synthesize glycogen. The elucidation of this unique glycogen biosynthesis pathway provides information necessary to further investigate the role of bacterial glycogen accumulation in rumen metabolism. PMID- 9361421 TI - Trehalose induces antagonism towards Pythium debaryanum in Pseudomonas fluorescens ATCC 17400. AB - Pseudomonas fluorescens ATCC 17400 shows in vitro activity against Pythium debaryanum under conditions of iron limitation. A lacZ reporter gene introduced by transposon mutagenesis into the P. fluorescens ATCC 17400 trehalase gene (treA) was induced by a factor released by the phytopathogen Pythium debaryanum. The induction of the lacZ gene was lost upon treatment of the Pythium supernatant with commercial trehalase. A trehalose concentration as low as 1 microM could induce the expression of treA. The mutation did not affect the wild-type potential for fungus antagonism but drastically decreased the osmotolerance of the mutant in liquid culture and suppressed the ability of P. fluorescens ATCC 17400 to utilize trehalose as a carbon source. A subsequent transposon insertion in treP, one of the trehalose phosphotransferase genes upstream of treA, silenced the lacZ gene. This double mutant restricted fungal growth only under conditions of high osmolarity, which probably results in internal trehalose accumulation. These data confirm the role of the disaccharide trehalose in osmotolerance, and they indicate its additional role as an initiator of or a signal for fungal antagonism. PMID- 9361423 TI - Genetic diversity and expression of the [NiFe] hydrogenase large-subunit gene of Desulfovibrio spp. in environmental samples. AB - The genetic diversity and expression of the [NiFe] hydrogenase large-subunit gene of Desulfovibrio spp. in environmental samples were determined in order to show in parallel the existing and active members of Desulfovibrio populations. DNA and total RNA were extracted from different anaerobic bioreactor samples; RNA was transcribed into cDNA. Subsequently, PCR was performed to amplify a ca.-440-bp fragment of the [NiFe] hydrogenase large-subunit gene and its mRNA. Denaturing gradient gel electrophoresis analysis was used to separate the PCR products according to their sequence and thereby to visualize the individual community members. Desulfovibrio strains corresponding to amplified [NiFe] hydrogenase transcripts were regarded as metabolically active, because in pure cultures transcripts were detectable in exponentially growing cells but not in cultures in the stationary phase. DNA sequencing and comparative sequence analysis were used to identify the detected organisms on the basis of their [NiFe] hydrogenase sequences. The genes of characterized Desulfovibrio spp. showed a considerable extent of divergence (ca. 30%), whereas sequences obtained from bacterial populations of the bioreactors showed a low level of variation and indicated the coexistence of closely related strains probably belonging to the species Desulfovibrio sulfodismutans. Under methanogenic conditions, all detected populations were active; under denitrifying conditions, no [NiFe] hydrogenase mRNA was visible. Changes in activity and composition of Desulfovibrio populations caused by changes in the environmental conditions could be monitored by using the approach described in this study. PMID- 9361424 TI - Bacteriophage-triggered defense systems: phage adaptation and design improvements. AB - A novel bacteriophage defense system, based on an inducible suicide gene, was challenged with a lactococcal bacteriophage to investigate the potential for phage adaptation. The defense system was encoded by pTRK414H, a high-copy-number replicon encoding a tightly regulated phi 31p trigger promoter fused to the lethal LlaIR+ restriction endonuclease cassette. Repeated transfers of Lactococcus lactis NCK690(pTRK414H) in the presence of phi 31 selected for phage phi 31 derivatives which were markedly less sensitive to phi 31p-LlaIR(+)-encoded restriction than the parental phage, phi 31. The efficiency of plaquing (EOP) on L. lactis NCK690(pTRK414H) was 10(-4) for phi 31 versus 0.4 for the derived phages. The mutant phages remained fully sensitive to LlaIR+ restriction, suggesting an alteration in the recognition or firing of the phi 31p promoter. Sequencing over the promoter region in four mutant phages revealed the identical C-to-A transversion, generating a Phe-to-Leu substitution, in a transcriptional activator of the phi 31p promoter, designated ORF2. The mutant phages were analyzed for their ability to induce the native phi 31p promoter element fused to a lacZst reporter gene. Compared to the parental phage, phi 31, lower levels of beta-galactosidase activity were induced throughout the lytic cycle, indicating that the strength at which the mutant phages activated the phi 31p promoter was altered. Based on these observations, improvements were made in promoter strength and restriction activity in an attempt to elevate the effectiveness of the phage triggered suicide system. When the phi 31p-LlaIR+ cassette was paired with other abortive defense systems, Per31 and AbiA, the EOP of phi 31 was reduced to < 10( 10) and the level of phage in the culture was lowered below the detection limits of the assay. PMID- 9361425 TI - A biosensor for environmental genotoxin screening based on an SOS lux assay in recombinant Escherichia coli cells. AB - A genetically controlled luminescent bacterial reporter assay, the SOS lux test, was developed for rapid detection of environmental genotoxins. The bioassay is based on the recombinant plasmid pPLS-1, which was constructed as a derivative of pBR322, carrying the promoterless luxCDABFE genes of Photobacterium leiognathi downstream of a truncated cda gene from ColD with a strong SOS promoter. E. coli recA+ strains containing this construction are inducible to high levels of light production in the presence of substances or agents that cause damage to the DNA of the cells. The light signal, reflecting the SOS-inducing potency, is recorded from the growing culture within 1 s, and the test results are available within 1 to 2 h. Induction of bioluminescence was demonstrated by treatment of E. coli C600(pPLS-1) with 6 genotoxic chemicals (mitomycin C, N-methyl-N'-nitro-N nitrosoguanidine, nalidixic acid, dimethylsulfate, hydrogen peroxide, and formaldehyde) and with UV and gamma radiation. A clear dose-response relationship was established for all eight genotoxins. The sensitivity of the SOS lux test is similar to that of other bioassays for genotoxicity or mutagenicity, such as the SOS chromotest, umu test, and Ames mutatest. These results indicate that the SOS lux test is potentially useful for the in situ and continuous detection of genotoxins. PMID- 9361427 TI - Detection of low levels of enteric viruses in metropolitan and airplane sewage. AB - To detect less prevalent viruses, such as wild-type polioviruses in sewage from a highly immunized community, a method was developed to efficiently recover viruses and remove PCR inhibitors. The method consisted of initial separation of solids from liquid, followed by solvent extractions, polyethylene glycol precipitations, Sephadex G-200 chromatography, and guanidinium isothiocyanate (GIT) extraction. To elute viruses from the separated solids, 0.5 M threonine (pH 7.5) was as efficient as 3% beef extract but conferred no PCR inhibition. In samples that were concentrated approximately 1,000-fold, 21% of the initially seeded viruses were recovered. When poliovirus type 3 (PV3) Sabin strain at low levels and PV1 LSc strain at high levels were seeded in raw sewage, PV3 was specifically detected in the final sample concentrates at sensitivities of 14 PFU by direct PCR and 0.7 PFU by GIT extraction-PCR. While applying the method to international airplane sewage, which contains high levels of solids as well as commercial sanitizers, 44% (7 of 16) of the samples were found to harbor enteroviruses by both cell culture infectivity and pan-enterovirus PCR analyses. Nucleotide sequencing of the PCR products revealed that multiple enterovirus genotypes were amplified from each final sewage concentrate, whereas the fewer virus genotypes detected by cell culture infectivity were probably the better growing strains. By this method, we demonstrated that air travel may contribute to the intercontinental dissemination of enteric pathogens. PMID- 9361426 TI - Heterologous expression of the Mycobacterium tuberculosis gene encoding antigen 85A in Corynebacterium glutamicum. AB - By using appropriate Corynebacterium glutamicum-Escherichia coli shuttle plasmids, the gene encoding the fibronectin-binding protein 85A (85A) from Mycobacterium tuberculosis was expressed in C. glutamicum, also an actinomycete and nonsporulating gram-positive rod bacterium, which is widely used in industrial amino acid production. The 85A gene was weakly expressed in C. glutamicum under the control of the ptac promoter from E. coli, but it was produced efficiently under the control of the promoter of the cspB gene encoding PS2, one of the two major secreted proteins from C. glutamicum. The 85A protein was produced in various forms, with or without its own signal sequence and with or without the signal sequence and the NH2-terminal (18-amino-acid) mature sequence of PS2. Western blot analysis with monoclonal antibodies raised against the M. tuberculosis antigen 85 complex showed that recombinant 85A protein was present in the corynebacterial cell wall extract and also released in extracellular culture medium. NH2-terminal microsequencing of recombinant 85A secreted by C. glutamicum showed that signal peptide was effectively cleaved off at the predicted site. The recombinant 85A protein was biologically active in vitro, inducing significant secretion of Th1 T-cell cytokines, particularly interleukin-2 and gamma interferon, in spleen cell cultures from mice vaccinated with live Mycobacterium bovis BCG. Heterologous expression of mycobacterial antigens in C. glutamicum now offers a potent tool for further immunological characterization and large scale preparation of these recombinant proteins. PMID- 9361428 TI - Improvement of Bacillus sphaericus toxicity against dipteran larvae by integration, via homologous recombination, of the Cry11A toxin gene from Bacillus thuringiensis subsp. israelensis. AB - Integrative plasmids were constructed to enable integration of foreign DNA into the chromosome of Bacillus sphaericus 2297 by in vivo recombination. Integration of the aphA3 kanamycin resistance gene by a two-step procedure demonstrated that this strategy was applicable with antibiotic resistance selection. Hybridization experiments evidenced two copies of the operon encoding the binary toxin from B. sphaericus in the recipient strain. The Bacillus thuringiensis subsp. israelensis cry11Aal gene (referred to as cry11A), encoding a delta-endotoxin with toxicity against Culex, Aedes, and Anopheles larvae, was integrated either by a single crossover event [strain 2297 (::pHT5601), harboring the entire recombinant plasmid] or by two successive crossover events [strain 2297 (::cry11A)]. The level of the Cry11A production in B. sphaericus was high; two crystalline inclusions were produced in strain 2297 (::pHT5601). Synthesis of the Cry11A toxin conferred toxicity to the recombinant strains against Aedes aegypti larvae, for which the parental strain was not toxic. Interestingly, the level of larvicidal activity of strain 2297 (::pHT5601) against Anopheles stephensi was as high as that of B. thuringiensis subsp. israelensis and suggested synergy between the B. thuringiensis and B. sphaericus toxins. The toxicities of parental and recombinant B. sphaericus strains against Culex quinquefasciatus were similar, but the recombinant strains killed the larvae more rapidly. The production of the Cry11A toxin in B. sphaericus also partially restored toxicity for C. quinquefasciatus larvae from a population resistant to B. sphaericus 1593. In vivo recombination therefore appears to be a promising approach to the creation of new B. sphaericus strains for vector control. PMID- 9361429 TI - Differentiation of Erwinia amylovora strains by pulsed-field gel electrophoresis. AB - Erwinia amylovora strains, isolated from several host plants in various geographic regions during different years, were analyzed by pulsed-field gel electrophoresis (PFGE) after digestion of the DNA from lysed, agar-embedded cells with rare-cutting restriction enzymes. The banding patterns obtained with enzyme XbaI digests revealed significant differences among strains from different areas. North American strains E9 and Ea-Rb, a Rubus strain, were highly divergent from other E. amylovora strains. French strains were different from central European and English strains. E. amylovora strains from central Europe and New Zealand had identical PFGE patters, as had strains from Egypt, Greece, and Turkey. PFGE of genomic DNA from American and English strains gave rise to dissimilar patterns. Patterns of some American strains resembled those from strains isolated in other parts of the world. The restriction fragment length polymorphisms observed by PFGE analysis can be used to group strains and may give hints about the course of distribution of the plant disease. From the sizes of the restriction fragments obtained, a molecular mass of approximately 4.5 Mb was calculated for the genome of E. amylovora. PMID- 9361430 TI - Sensitive detection of viable Listeria monocytogenes by reverse transcription PCR. AB - Detection of pathogens in contaminated food products by PCR can result in false positive data due to the amplification of DNA from nonviable cells. A new method based on reverse transcription-PCR (RT-PCR) amplification of mRNA for the specific detection of viable Listeria monocytogenes was developed. The expression of three L. monocytogenes genes, iap, hly, and prfA, was examined to determine a suitable target for amplification of RT-PCR. Total RNA from L. monocytogenes was isolated, and following DNase treatment, the RNA was amplified by both RT-PCR and PCR with primers specific for the three genes. Amplicon detection was accomplished by Southern hybridization to digoxigenin-labeled gene probes. The levels of expression of these three genes differed markedly, and the results indicated that the iap gene would provide a good target for development of a specific method for detection of viable L. monocytogenes based on RT-PCR amplification. After a 1-h enrichment, the 371-bp iap-specific product was detected with a sensitivity of ca. 10 to 15 CFU/ml from pure culture. Detection of the 713-bp hly-specific amplicon was ca. 4,000 times less sensitive after 1 h, whereas detection of the 508-bp prfA product showed the lowest level of sensitivity, with detection not observed until after a 5-h enrichment period. The amplification of the iap mRNA was specific for L. monocytogenes. Overall, the assay could be completed in ca. 54 h. The use of RT-PCR amplification for the detection of viable L. monocytogenes was validated in artificially contaminated cooked ground beef. Following a 2-h enrichment incubation, the iap-specific amplification product could be detected in a cooked meat sample that was originally inoculated with ca. 3 CFU/g. These results support the usefulness of RT-PCR amplification of mRNA as a sensitive method for the specific detection of viable L. monocytogenes and indicate that this method may prove useful in the detection of this pathogen in ready-to-eat, refrigerated meat products. PMID- 9361431 TI - Contribution of the 65-kilodalton protein encoded by the cloned gene cry19A to the mosquitocidal activity of Bacillus thuringiensis subsp. jegathesan. AB - Two new crystal protein genes, cry19A and orf2, isolated from Bacillus thuringiensis subsp. jegathesan were cloned and characterized. The cry19A gene encodes a 74.7-kDa protein, and the orf2 gene encodes a 60-kDa protein. Cry19A contains the five conserved blocks present in most B. thuringiensis delta endotoxins. The ORF2 amino acid sequence is similar to that of the carboxy terminus of Cry4 proteins. The cry 19A gene was expressed independently or in combination with orf2 in a crystal-negative B. thuringiensis host. The proteins accumulated as inclusions. Purified inclusions containing either Cry19A alone or Cry19A and ORF2 together were toxic to Anopheles stephensi and Culex pipiens mosquito larvae. They were more toxic to C. pipiens than to A. stephensi. However, inclusions containing Cry19A and ORF2 together were more toxic than inclusions of Cry19A alone but less toxic than the wild-type inclusions of B. thuringiensis subsp. jegathesan. PMID- 9361432 TI - Recombinant luminescent bacteria for measuring bioavailable arsenite and antimonite. AB - Luminescent bacterial strains for the measurement of bioavailable arsenite and antimony were constructed. The expression of firefly luciferase was controlled by the regulatory unit of the ars operon of Staphylococcus aureus plasmid pI258 in recombinant plasmid pTOO21, with S. aureus RN4220, Bacillus subtilis BR151, and Escherichia coli MC1061 as host strains. Strain RN4220(pTOO21) was found to be the most sensitive for metal detection responding to arsenite, antimonite, and cadmium, the lowest detectable concentrations being 100, 33, and 330 nM, respectively. Strains BR151(pTOO21) and MC1061(pTOO21) responded to arsenite, arsenate, antimonite, and cadmium, the lowest detectable concentrations being 3.3 and 330 microM and 330 and 330 nM with BR151(pTOO21), respectively, and 3.3, 33, 3.3, and 33 microM with MC1061(pTOO21), respectively. In the absence of the mentioned ions, the expression of luciferase was repressed and only a small amount of background light was emitted. Other ions did not notably interfere with the measurement in any of the strains tested. Freeze-drying of the cells did not decrease the sensitivity of the detection of arsenite; however, the induction coefficients were somewhat lower. PMID- 9361433 TI - Development of a diagnostic DNA probe for xanthomonads causing bacterial spot of peppers and tomatoes. AB - Xanthomonas vesicatoria and Xanthomonas axonopodis pv. vesicatoria, causal agents for bacterial spot of tomatoes and peppers, are difficult to distinguish from other xanthomonads found on field-grown plants. A genomic subtraction technique with subtracter DNA from nonpathogenic epiphytic xanthomonads was used to enrich for sequences that could serve as diagnostic probes for these pathogens. A 1.75 kb PstI-NotI fragment (KK1750) that preferentially hybridized to X. vesicatoria DNA and X. axonopodis pv. vesicatoria DNA was identified and cloned into pBluescriptII KS+. It hybridized to 46 (89%) of the 52 geographically diverse bacterial spot-causing xanthomonad (bsx) strains included in this study. The six probe-negative strains were genotypically and pathologically distinct from the other bsx strains studied. Two of these strains, DC91-1 and DC91-2, resembled X. campestris pv. raphani in that they also infected radish plants. X. vesicatoria strains gave stronger hybridization signals than did most X. axonopodis pv. vesicatoria strains. In a survey of 110 non-bsx plant-associated bacteria, including 44 nonvesicatoria phytopathogenic xanthomonads and 43 epiphytic xanthomonad strains, only 8 were probe positive, but the responses were weak. Further testing revealed that one of these strains was actually a tomato pathogen. Pulsed-field gel electrophoresis and Southern blot analysis of 46 bsx strains indicated that KK1750 sequences could be either plasmid-borne (10.9%), chromosome-borne (43.4%), or present on both replicons (45.7%). KK1750, unique in its ability to hybridize to both X. axonopodis pv. vesicatoria and X. vesicatoria strains, should facilitate disease diagnosis for these important plant pathogens. PMID- 9361434 TI - Biodiversity of a Burkholderia cepacia population isolated from the maize rhizosphere at different plant growth stages. AB - A Burkholderia cepacia population naturally occurring in the rhizosphere of Zea mays was investigated in order to assess the degree of root association and microbial biodiversity at five stages of plant growth. The bacterial strains isolated on semiselective PCAT medium were mostly assigned to the species B. cepacia by an analysis of the restriction patterns produced by amplified DNA coding for 16S rRNA (16S rDNA) (ARDRA) with the enzyme AluI. Partial 16S rDNA nucleotide sequences of some randomly chosen isolates confirmed the ARDRA results. Throughout the study, B. cepacia was strictly associated with maize roots, ranging from 0.6 to 3.6% of the total cultivable microflora. Biodiversity among 83 B. cepacia isolates was analyzed by the random amplified polymorphic DNA (RAPD) technique with two 10-mer primers. An analysis of RAPD patterns by the analysis of molecular variance method revealed a high level of intraspecific genetic diversity in this B. cepacia population. Moreover, the genetic diversity was related to divergences among maize root samplings, with microbial genetic variability markedly higher in the first stages of plant growth; in other words, the biodiversity of this rhizosphere bacterial population decreased over time. PMID- 9361435 TI - Association of mercury resistance with antibiotic resistance in the gram-negative fecal bacteria of primates. AB - Gram-negative fecal bacterial from three longitudinal Hg exposure experiments and from two independent survey collections were examined for their carriage of the mercury resistance (mer) locus. The occurrence of antibiotic resistance was also assessed in both mercury-resistant (Hgr) and mercury-susceptible (Hgs) isolates from the same collections. The longitudinal studies involved exposure of the intestinal flora to Hg released from amalgam "silver" dental restorations in six monkeys. Hgr strains were recovered before the installation of amalgams, and frequently these became the dominant strains while amalgams were installed. Such persistent Hgr strains always carried the same mer locus throughout the experiments. In both the longitudinal and survey collections, certain mer loci were preferentially associated with one genus, whereas other mer loci were recovered from many genera. In general, strains with any mer locus were more likely to be multiresistant than were strains without mer loci; this clustering tendency was also seen for antibiotic resistance genes. However, the association of antibiotic multiresistance with mer loci was not random; regardless of source, certain mer loci occurred in highly multiresistant strains (with as many as seven antibiotic resistances), whereas other mer loci were found in strains without any antibiotic resistance. The majority of highly multiresistant Hgr strains also carried genes characteristic of an integron, a novel genetic element which enables the formation of tandem arrays of antibiotic resistance genes. Hgr strains lacking antibiotic resistance showed no evidence of integron components. PMID- 9361437 TI - Characterization of microbial diversity by determining terminal restriction fragment length polymorphisms of genes encoding 16S rRNA. AB - A quantitative molecular technique was developed for rapid analysis of microbial community diversity in various environments. The technique employed PCR in which one of the two primers used was fluorescently labeled at the 5' end and was used to amplify a selected region of bacterial genes encoding 16S rRNA from total community DNA. The PCR product was digested with restriction enzymes, and the fluorescently labeled terminal restriction fragment was precisely measured by using an automated DNA sequencer. Computer-simulated analysis of terminal restriction fragment length polymorphisms (T-RFLP) for 1,002 eubacterial sequences showed that with proper selection of PCR primers and restriction enzymes, 686 sequences could be PCR amplified and classified into 233 unique terminal restriction fragment lengths or "ribotypes." Using T-RFLP, we were able to distinguish all bacterial strains in a model bacterial community, and the pattern was consistent with the predicted outcome. Analysis of complex bacterial communities with T-RFLP revealed high species diversity in activated sludge, bioreactor sludge, aquifer sand, and termite guts; as many as 72 unique ribotypes were found in these communities, with 36 ribotypes observed in the termite guts. The community T-RFLP patterns were numerically analyzed and hierarchically clustered. The pattern derived from termite guts was found to be distinctly different from the patterns derived from the other three communities. Overall, our results demonstrated that T-RFLP is a powerful tool for assessing the diversity of complex bacterial communities and for rapidly comparing the community structure and diversity of different ecosystems. PMID- 9361436 TI - Characterization of DNA polymerase from Pyrococcus sp. strain KOD1 and its application to PCR. AB - The DNA polymerase gene from the archaeon Pyrococcus sp. strain KOD1 (KOD DNA polymerase) contains a long open reading frame of 5,013 bases that encodes 1,671 amino acid residues (GenBank accession no. D29671). Similarity analysis revealed that the DNA polymerase contained a putative 3'-5' exonuclease activity and two in-frame intervening sequences of 1,080 bp (360 amino acids; KOD pol intein-1) and 1,611 bp (537 amino acids; KOD pol intein-2), which are located in the middle of regions conserved among eukaryotic and archaeal alpha-like DNA polymerases. The mature form of the DNA polymerase gene was expressed in Escherichia coli, and the recombinant enzyme was purified and characterized. 3'-5' exonuclease activity was confirmed, and although KOD DNA polymerase's optimum temperature (75 degrees C) and mutation frequency (3.5 x 10(-3)) were similar to those of a DNA polymerase from Pyrococcus furiosus (Pfu DNA polymerase), the KOD DNA polymerase exhibited an extension rate (100 to 130 nucleotides/s) 5 times higher and a processivity (persistence of sequential nucleotide polymerization) 10 to 15 times higher than those of Pfu DNA polymerase. These characteristics enabled the KOD DNA polymerase to perform a more accurate PCR in a shorter reaction time. PMID- 9361438 TI - Metal resistance in Acidocella strains and plasmid-mediated transfer of this characteristic to Acidiphilium multivorum and Escherichia coli. AB - Acidophilic heterotrophic strain GS19h of the genus Acidocella exhibited extremely high resistance to CdSO4 and ZnSO4, with a MIC of 1 M for each. The respective MICs for an Acidocella aminolytica strain were 400 and 600 mM. The MICs of NiSO4 for the above strains were 200 and 175 mM, respectively. These strains were also resistant to CuSO4, the MICs being 20 and 40 mM, respectively. An Acidocella facilis strain showed resistance only to ZnSO4, with a MIC of 150 mM. The metal salts, in general, extended the lag period, log period, and generation time, with decreases in growth rate and optimum growth. A. aminolytica and strain GS19h each contain more than one plasmid, while A. facilis contains none. After transformation by electroporation with the plasmid preparation from strain GS19h, an Acidiphilium multivorum strain became highly resistant to cadmium and zinc, and the plasmid profile of the transformed cells was found to differ from that of the original Acidiphilium multivorum strain. Escherichia coli HB101 and DH5 alpha also exhibited more resistance to these metals, especially zinc, after transformation with the total plasmid preparation of strain GS19h or a 24.0-MDa plasmid of the same strain, although no plasmid was detected in the transformed cells. Thus, the results derived mainly through genetic experiments demonstrate for the first time the plasmid-mediated transfer of metal resistance for an acidophilic bacterium. PMID- 9361439 TI - Imaging of Lactobacillus brevis single cells and microcolonies without a microscope by an ultrasensitive chemiluminescent enzyme immunoassay with a photon counting television camera. AB - An ultrasensitive chemiluminescent enzyme immunoassay (CLEIA) was developed for the rapid detection and quantification of Lactobacillus brevis contaminants in beer and pitching yeast (Saccharomyces cerevisiae slurry collected for reinoculation). L. brevis cells trapped on a 47-mm nucleopore membrane (0.4 micron pore size) were reacted with a peroxidase-labelled Lactobacillus group E antibody and then subjected to an enhanced CLEIA analysis with 4-iodophenol as the enhancer. The combination of a nucleopore membrane with low background characteristics that enables the antigen-antibody reaction to proceed through the pores of the membrane and a labelled antibody prepared by the maleimide hinge method with minimal nonspecific binding characteristics was essential to minimize background in the detection of single cells. An ultrahigh sensitive charge coupled device (CCD) camera equipped with a fiber optics image intensifier permitted the imaging of single cells. A clear correlation existed between the number of luminescent spots observed and the plate count [y (CLEIA) = 0.990x (plate count) + 15.9, where n = 7, r = 0.993, and P < 0.001]. Microscopic observation confirmed that the luminescent spots were produced by single cells. This assay could be used to detect approximately 20 L. brevis cells in 633 ml of beer within 4 h. Our ultrasensitive CLEIA could also be used to detect microcolonies approximately 20 microns in diameter which had formed on a membrane after 15 to 18 h of incubation. This method, which we called the microcolony immunoluminescence (MIL) method, increased the signal-to-noise ratio dramatically. The MIL method could be used to detect a 10(0) level of L. brevis contamination in 633 ml of beer and a 1/10(8) level of L. brevis contamination in pitching yeast within 1 day (15 to 18 h to form microcolonies and 2 h for CLEIA). PMID- 9361440 TI - Development and application of monoclonal antibodies for in situ detection of indigenous bacterial strains in aquatic ecosystems. AB - Strain-specific monoclonal antibodies (MAbs) were developed for three different bacterial isolates obtained from a freshwater environment (Lake Plusssee) in the spring of 1990. The three isolates, which were identified by molecular methods, were as follows: Cytophaga johnsonae PX62, Comamonas acidovorans PX54, and Aeromonas hydrophila PU7718. These strains represented three species that were detected in high abundance during a set of mesocosm experiments in Lake Plusssee by the direct analysis of low-molecular-weight RNAs from bacterioplankton. We developed one MAb each for the bacterial isolates PX54 and PU7718 that did not show any cross-reactivity with other bacterial strains by immunofluorescence microscopy. Each MAb recognized the general lipopolysaccharide fraction of the homologous strain. These MAbs were tested successfully for their ability to be used for the in situ detection and counting of bacteria in lake water by immunofluorescence microscopy. During the spring of 1993, A. hydrophila PU7718 showed a depth distribution in Lake Plusssee with a pronounced maximum abundance at 6 m, whereas Comamonas acidovorans PX54 showed a depth distribution with a maximum abundance at the surface. The application of these MAbs to the freshwater samples enabled us to determine the cell morphologies and microhabitats of these strains within their natural environment. The presence of as many as 8,000 cells of these strains per ml in their original habitats 3 years after their initial isolation demonstrated the persistence of individual strains of heterotrophic bacteria over long time spans in pelagic habitats. PMID- 9361441 TI - Green fluorescent protein as a marker for Pseudomonas spp. AB - The development of sensitive methods for observing individual bacterial cells in a population in experimental models and natural environments, such as in biofilms or on plant roots, is of great importance for studying these systems. We report the construction of plasmids which constitutively express a bright mutant of the green fluorescent protein of the jellyfish Aequorea victoria and are stably maintained in Pseudomonas spp. We demonstrate the utility of these plasmids to detect individual cells in two experimental laboratory systems: (i) the examination of a mixed bacterial population of Pseudomonas aeruginosa and Burkholderia cepacia attached to an abiotic surface and (ii) the association of Pseudomonas fluorescens WCS365 with tomato seedling roots. We also show that two plasmids, pSMC2 and pGB5, are particularly useful, because they are stable in the absence of antibiotic selection, they place an undetectable metabolic burden on cells that carry the plasmids, and cells carrying these constructs continue to fluoresce even after 7 days in culture without the addition of fresh nutrients. The construction of improved Escherichia coli-Pseudomonas shuttle vectors which carry multiple drug resistance markers also is described. PMID- 9361442 TI - Specific detection and confirmation of Campylobacter jejuni by DNA hybridization and PCR. AB - Conventional detection and confirmation methods for Campylobacter jejuni are lengthy and tedious. A rapid hybridization protocol in which a 1,475-bp chromogen labelled DNA probe (pDT1720) and Campylobacter strains filtered and grown on 0.22 micron-pore-size hydrophobic grid membrane filters (HGMFs) are used was developed. Among the environmental and clinical isolates of C. jejuni, Campylobacter coli, Campylobacter jejuni subsp. doylei, Campylobacter lari, and Arcobacter nitrofigilis and a panel of 310 unrelated bacterial strains tested, only C. jejuni and C. jejuni subsp. doylei isolates hybridized with the probe under stringent conditions. The specificity of the probe was confirmed when the protocol was applied to spiked skim milk and chicken rinse samples. Based on the nucleotide sequence of pDT1720, a pair of oligonucleotide primers was designed for PCR amplification of DNA from Campylobacter spp. and other food pathogens grown overnight in selective Mueller-Hinton broth with cefoperazone and growth supplements. All C. jejuni strains tested, including DNase-producing strains and C. jejuni subsp. doylei, produced a specific 402-bp amplicon, as confirmed by restriction and Southern blot analysis. The detection range of the assay was as low as 3 CFU per PCR to as high as 10(5) CFU per PCR for pure cultures. Overnight enrichment of chicken rinse samples spiked initially with as little as approximately 10 CFU/ml produced amplicons after the PCR. No amplicon was detected with any of the other bacterial strains tested or from the chicken background microflora. Since C. jejuni is responsible for 99% of Campylobacter contamination in poultry, PCR and HGMF hybridization were performed on naturally contaminated chicken rinse samples, and the results were compared with the results of conventional cultural isolation on Preston agar. All samples confirmed to be culture positive for C. jejuni were also identified by DNA hybridization and PCR amplification, thus confirming that these DNA-based technologies are suitable alternatives to time-consuming conventional detection methods. DNA hybridization, besides being sensitive, also has the potential to be used in direct enumeration of C. jejuni organisms in chicken samples. PMID- 9361443 TI - Controlled gene expression systems for lactic acid bacteria: transferable nisin inducible expression cassettes for Lactococcus, Leuconostoc, and Lactobacillus spp. AB - A transferable dual-plasmid inducible gene expression system for use in lactic acid bacteria that is based on the autoregulatory properties of the antimicrobial peptide nisin produced by Lactococcus lactis was developed. Introduction of the two plasmids allowed nisin-inducible gene expression in Lactococcus lactis MG1363, Leuconostoc lactis NZ6091, and Lactobacillus helveticus CNRZ32. Typically, the beta-glucuronidase activity (used as a reporter in this study) remained below the detection limits under noninducing conditions and could be raised to high levels, by addition of subinhibitory amounts of nisin to the growth medium, while exhibiting a linear dose-response relationship. These results demonstrate that the nisin-inducible system can be functionally implemented in lactic acid bacteria other than Lactococcus lactis. PMID- 9361444 TI - Virulence factors of verocytotoxin-producing Escherichia coli isolated from raw meats. AB - PCR for verocytotoxin-producing Escherichia coli (VTEC) was positive in 4.6% of 2,440 raw meat samples; only beef, sheep, and venison samples were positive. None of the isolated VTEC strains belonged to serogroup O157. Additional virulence factors were detected in only a minority of strains, suggesting that most of these meat VTEC isolates are not pathogenic. PMID- 9361445 TI - Application of the extracellular alpha-amylase gene from Streptococcus bovis 148 to construction of a secretion vector for yogurt starter strains. AB - Streptococcus thermophilus ATCC 19258, Lactobacillus delbrueckii subsp. bulgaricus T-11, and Lactococcus lactis subsp. lactis IL1403 were transformed with the alpha-amylase gene (amyA) from Streptococcus bovis 148 by using a wide host-range vector, and all the transformants secreted the alpha-amylase successfully. Since the promoter and the secretion signal of the amyA gene were functional in these strains, we constructed a secretion vector using the expression elements of amyA. Trials to secrete foreign enzymes in yogurt starter strains were performed using this novel secretion vector. PMID- 9361446 TI - A relative of the broad-host-range plasmid RSF1010 detected in Erwinia amylovora. AB - Streptomycin- and sulfonamide-resistant Erwinia amylovora CA3R from California contained an 8.7-kb plasmid, pEa8.7, with a sulII-strA-strB resistance region; furthermore, PCR, sequencing, hybridization, and restriction analyses showed that pEa8.7 was closely related or identical to broad-host-range plasmid RSF1010. Although RSF1010 has been found in a variety of bacteria, this is the first report of its presence in plant pathogenic bacteria. PMID- 9361447 TI - Use of nucleic acid dyes SYTO-13, TOTO-1, and YOYO-1 in the study of Escherichia coli and marine prokaryotic populations by flow cytometry. AB - Three nucleic acid dyes (SYTO-13, TOTO-1, and YOYO-1) were tested on cultures of Escherichia coli and marine prokaryote populations. These dyes stain the RNA and DNA in E. coli but only respond to DNA in marine populations, according to the histograms obtained after DNase and RNase treatments. PMID- 9361448 TI - Small-subunit rRNA genes and in situ hybridization with oligonucleotides specific for the bacterial symbionts in the larvae of the bryozoan Bugula neritina and proposal of "Candidatus endobugula sertula". AB - Larvae of the bryozoan Bugula neritina harbor bacterial symbionts. These symbionts were identified as a novel species of gamma-proteobacterium, based on ribosomal small-subunit rRNA gene sequences. In situ hybridization with oligonucleotides specific for the symbiont confirmed the origin of the sequence. The taxonomic status "Candidatus Endobugula sertula" is proposed for the larval symbiont. PMID- 9361450 TI - [OECD series on principles of good laboratory practice and compliance monitoring]. PMID- 9361449 TI - Methane and trichloroethylene oxidation by an estuarine methanotroph, Methylobacter sp. strain BB5.1. AB - An estuarine methanotroph was isolated from sediment enrichments and designated Methylobacter sp. strain BB5.1. In cells grown on medium with added copper, oxidation of methane and trichloroethylene occurred with similar Ks values, but the Vmax for trichloroethylene oxidation was only 0.1% of the methane oxidation Vmax. Cells grown on low-copper medium did not oxidize trichloroethylene and showed a variable rate of methane oxidation. PMID- 9361451 TI - [Molecular evolution of MHC DQA genes. I. The maintenance of interallelic divergence and the influence of GC content on gene structure]. AB - The analyses of the proportion of synonymous and missense nucleotide substitution (PS and PN) in different exons, antigen recognition sites (ARS) and non-ARS of EN2 (NAEN2) of 23 alleles at MHC DQA loci in 7 mammal species gave rise to the following findings. (1) PN was about twice as much as PS in ARS among the alleles at DQA1 of any given species, i.e. 7 alleles at HLA-DQA1 or 8 alleles at IaAa this accords with overdominant selection; (2) PS showed more or less the same as PN in ARS among different loci (DQA1 or DQA2 in different species, or DQA1 and DQA2 in one species) or NAEN2 of all comparative pairs, this conforms the expectation of neutral selection; (3) In exon4 and exon3, not only was the substitution proportion extremely low, but also PS was much higher than PN (the ratio PS over PN is 19.5 in alleles at IaAa of mouse and 4 among alleles at different loci), this coincides obviously with purification selection. The analysis of GC content of MHC DQA showed that its peaks were in the regions corresponding to the middle bulks of some domains, that the highest and constant level was in exon4 and that GC content in the third codon position (GC III content) associates inversely with PS. These results indicate that the specified maintenance mechanisms of interallelic diversity relevant to their functions exist in given exons corresponding to some domains of the same MHC DQA locus and GC III content is an important factor in keeping the structure and function of gene under selection constraint. The method for estimating nucleotide substitution proportion was modified. PMID- 9361452 TI - [Cloning of BRCA1 cDNA and detection of BRCA1 mRNA expression in breast cancer cells]. AB - The fragment of BRCA1 cDNA obtained by reverse transcription and polymerase chain reaction(RT-PCR) was inserted into plasmid pUC118 and demonstrated by DNA sequencing. Nucleotide sequence analysis demonstrated that the cloned cDNA for BRCA1 includes zinc finger domain. Two differences in nucleotides were found as compared with the sequence published. One occurs at nucleotide number 409 where Creplaced by A (Asp-->Glu). Another difference occurs at nucleotide number 879 where A replaced by T (samesense mutation). In order to further study the relationship-between BRCA1 function and breast cancer, the probe was prepared from the recombinant plasmid and then hybridized to total RNAs from 6 cases of breast cancer. Compared with normal cells, the expression level of BRCA1 mRNA was normal in 4, decreased markedly in 1, and in one patient there was no any expression of BRCA1 mRNA at all. The results suggested that the expression of BRCA1 mRNA was relatively low in some breast cancer cells. PMID- 9361453 TI - [Cloning and squencing of human thrombopoietin (hTPO) cDNA and it's expression in COS-7 cells]. AB - Two hTPO cDNA segments (N-terminal and C-terminal) were amplified from human fetal liver mRNA by using separate reverse-transcription PCR reactions, and cloned into pUC19. Their sequences were identical with that previously reported. Then the full length cDNA of hTPO was obtained from the two cDNA fragments, cloned into the shuttle vector pSVK3 and transiently expressed in COS-7 cells. The activity of the expression product was demonstrated with the stimulation of CFU-Meg. PMID- 9361454 TI - [Localization of PTH gene on pig chromosome 14q25-q28 by in situ hybridization]. AB - The human parathyroid hormone (PTH) genic DNA, as a probe, was labelled with tritium(3H) using nick translation and random oligonucleotide primers methods. Metaphase chromosomal G-bands were prepared from cultured blood lymphocytes of domestic pig. After in situ hybridization and autoradiographly, the number of silver grains on every chromosome was calculated. The result showed that PTH gene is located at chromosome 14q25-q28. The relevent points of this study are discussed. PMID- 9361456 TI - [Mitochondrial DNA sequence evolution and phylogenetic relationships of gibbons]. AB - The phylogenetic relationships of gibbons are still open questions. We have sequenced a mitochondrial cytochrome b gene fragment from Hylobates hoolock, H. concolor, H. lar and H. syndactylus. Combined with the sequences from Garza and Woodruff (1992), we have constructed a comprehensive phylogenetic tree of the gibbons using the maximum-parsimony analysis. Our results suggested that the gibbons should be divided into four groups: (1) hoolock, (2) syndactylus, (3) agilis, lar, muelleri and klossi, and (4) concolor, which correspond to the four morphological subgenera. There are at least four distinct clades in the concolor population, which indicates that the concolor may be divided into at least four species. Therefore, those four clades should be managed separately with the same conservation effort. PMID- 9361455 TI - [Genetic analysis on methylnitrosourea (MNU) induced mouse T-cell lymphomas]. AB - Since nonrandum chromosome changes in neoplastic cells have proven to be good indicators of gene alteration site related to transformation, the authors examined the chromosomes of T-cell lymphomas induced in mice strain RF/J with methylnitrosourea (MNU). All treated mice developed thymic lymphomas within 10 weeks after injection. Chromosomes of the thymus cells were examined at intervals before and during lymphoma development, as well as after the lymphomes were transmitted in syngeneic and nude mice for a period up to 424 days. In preparations made from the thymus and transmitted cells in both syngeneic and nude mice nonrandom quantitative and structural alterations were found involving X, 15, 14, 3, 12 chromosomes (showing in decreasing order of the frequency of alterations), suggesting that these chromosomes carry genes (oncogenes or tumor suppressor genes). MNU thus appears not only to be tissue specific but also chromosome specific in its effects. The neoplastic growth is resulted from a large number of sets of altered genes. Thus, if MNU preferentially target some of these sites, the probability of its induced transformation would be high. This may be the reason to explain its high clastogenicity. PMID- 9361457 TI - [The genetical effects of degUS gene in Bacillus subtilis Ki-2-132]. AB - Using the methods of recombination and gene disruption, the effects of degUS gene in Bacillus subtilis Ki-2-132 were studied. The results showed that the gene could affect all protease-producing, competence formation, cell mobility and repression effects of glucose on protease-production. This implies that it is a pleitropic gene in Bacillus subtilis Ki-2-132. The disruption of the gene caused morphological changes and repressed the expression of aprE in vectors. PMID- 9361458 TI - Care of the aged--a long haul ahead. PMID- 9361459 TI - Ageing in India--an overview. AB - Accelerated population ageing experienced in the last few decades is an unprecedented phenomenon. Currently, this is more in the developing countries. Soon three-fourths of the elderly will be in the developing world. From 1990 to 2025, the elderly population in Asia will rise from 50 per cent of the world's elderly to 58 per cent, in Africa and Latin America from 5 to 7 per cent, but in Europe the figure will drop from 19 to 12 per cent of the world's elderly. The life span has increased in India from 32 yr in 1947 to more than 62 yr now. From the morbidity point of view, almost 50 per cent of the Indian elderly have chronic diseases and 5 per cent suffer from immobility. There are several vulnerable groups and a big disadvantaged lot are elderly females who are one of the fastest growing segments, which will increase to become 4 times the current figure, by 2025. In spite of professional disinterest in the speciality, recent trends indicate the beginning of sensitization of medical teachers, advancing speciality of psychosocial gerontology and availability of some research funds. Importance of training of health professionals and priorities in gerontological research are also under consideration. Infections still take a heavy toll of our elderly population apart from well known degenerative disorders. Limitations of a developing country further influence the morbidity pattern in various ways. Nutritional deficiencies are common and often subclinical thus escaping the desired interventions. Coronary heart disease, hypertension, mental and many other disorders in the elderly have been reported as isolated observations highlighting differences from those made in the Western countries. Socio economically, the traditional support of extended families is rapidly undergoing erosion making the elderly further vulnerable. This causes more emotional and psychological problems while the State finds itself helpless in providing a comprehensive care to its large chunk of elderly population. It will be important to surmise and predetermine the future factors that are going to modify the diverse patterns of morbidity, disability and mortality in regional context. PMID- 9361460 TI - Chronic morbidity profile among elderly. AB - The most common health problems of the elderly are related to chronic disease as a result of increase in life expectancy. In India, sporadic data have been collected on different health problems of the elderly. While epidemiologic studies specifically targeted at the elderly population are sparce, the Indian Council of Medical Research (ICMR) has carried out several studies on specific chronic disorders such as hearing impairment, blindness, cardiovascular diseases, cancer etc. The data from these studies covering the aged population have been utilised to provide a chronic morbidity profile of the elderly. Based upon the population estimates, the disease load in the Indian elderly population has been estimated. Hearing impairment is the most common morbidity, followed by visual impairment. The common risk factors associated with these chronic disease, are reported upon, and measures for intervention are suggested, wherever feasible. The paper does not cover common morbidities, such as locomotor, urinary and sleep disturbances, which have been reported in other surveys. The availability of population based data from India, and derives the disease burden due to chronic diseases in the elderly is emphasised. Such data can be used to generate the pattern of health problems in the elderly, for initiating appropriate intervention strategies and for fixing priorities for planning health care services amongst the elderly. PMID- 9361461 TI - Infections in the elderly. AB - Ageing of the immune system is a complex process involving both humoral and cell mediated immunity. Along with decline in immunity, morphological changes in various organ makes the elderly especially vulnerable to infection. In clinical practice, infections of respiratory tract and urinary tract, endocarditis, septicaemia and tuberculosis are commonly encountered in elderly subjects Atypical clinical presentation, slow response to treatment and high mortality are hall marks of infection in order patients. Antibiotic therapy in elderly needs to be early, empirical and broad spectrum through parenteral route, with early change over to oral therapy. Aminopenicillins and cephalosporins are safer drugs in old age as compared to aminoglycosides. Pneumococcal and influenza vaccines are recommended in elderly subjects with medical conditions with higher risk of mortality and complications. PMID- 9361462 TI - Renal & prostatic disorders in the elderly. AB - The population of aged people is increasing in number all over the world along with the problems associated with senescence. The functional and morphological changes that occur with ageing are accompanied by an increased risk of certain conditions like drug-induced nephrotoxicity and acute tubular necrosis. Elderly patients of end-stage renal disease can undergo renal replacement therapy with acceptably good results. If free from any medical and other illnesses, elderly persons can be considered for kidney donation without any increased risk for surgery or anaesthesia. However, such kidneys are functionally not as good as kidneys from young individuals. Prostatic diseases like prostatic hyperplasia and cancer are more a concern of the aged than the younger population. Besides, there is an apprehension about the increased risk of anaesthesia due to the frequent presence of other co-existent illnesses in the senile population. Less morbid therapeutic methods are available to deal with prostatic disorders but one should not hesitate to undertake major open or endoscopic surgeries in such patients, should it be necessary. PMID- 9361463 TI - Gastrointestinal problems in the elderly. AB - Improvements in nutrition and health care have led to increased life expectancy in our country, which occasioned this review of gastrointestinal problems in the elderly. Some gastrointestinal symptoms may be secondary to age-related physiological changes (e.g., presbyoesophagus). Certain diseases (e.g., diverticulosis) may be more common in the elderly. On the other hand, the elderly may have unusual presentations of common diseases (e.g., complicated peptic ulcer disease). Each of these types of problems has been detailed in this review. Included is a preliminary analysis of hospitalised elderly patients which illuminates serious gastrointestinal problems afflicting the elderly in India. PMID- 9361464 TI - Cataract related blindness in India & its social implications. AB - The prevalence of blindness in India is 14.9 per 1000. Eighty per cent of this blindness is due to cataract alone. Most of the cataract blinds in the country are in the rural areas while the surgical service delivery network is concentrated in the urban areas. Thus a large proportion of patients in the rural areas continue to remain blind. This situation has many social implications. There is loss of productivity, breakdown of interpersonal relationships, depressive manifestations, loss of self esteem and most patients lead an isolated humiliating life. Patients lack information on the available services and continue to remain blind for years even after being diagnosed as operable. This is unfortunate because cataract surgery is one of the most cost effective health interventions known and most operated patients, irrespective of the surgical technique, are immensely satisfied with the level of visual rehabilitation after surgery. PMID- 9361465 TI - Strokes in the elderly: prevalence, risk factors & the strategies for prevention. AB - Current demographic trends suggest that the Indian population will survive through the peak years of occurrence of stroke (age 55-65 yr) and stroke survivors in the elderly with varying degree of residual disability, will be a major medical problem. The available data from community surveys from different regions of India for 'hemiplegia' presumed to be of vascular origin indicate a crude prevalence rate in the range of 200 per 100,000 persons. Thus, the anticipated costs of rehabilitation of stroke-victims will pose enormous socio economic burden on our meagre health-care resources, similar to what is now faced by industrialised nations in the West. Therefore, prevention of strokes at any age should be our main strategy in national health planning. Among all risk factors for strokes, hypertension is one of the most important and treatable factor. Community screening surveys, by well defined WHO protocol, have shown that nearly 15 per cent of the urban population is 'hypertensive' (160/95 mm Hg or more). Though high blood pressure has the highest attributable risk for stroke, there are many reasons such as patient's compliance in taking medicines and poor follow up in clinical practice that may lead to failure in reducing stroke mortality. In subjects who have transient ischaemic attacks (TIAs), regular use of antiplatelet agents like aspirin in prevention of stroke is well established. It is also mandatory to prohibit tobacco use and adjust dietary habits to control body weight, and associated conditions like diabetes mellitus etc., should be treated. It is advisable to initiate community screening surveys on well defined populations for early detection of hypertension and TIAs. Primary health care centres should be the base-stations for these surveys because data gathered from urban hospitals will not truly reflect the crude prevalence rates for the community to design practical prevention programmes. PMID- 9361466 TI - Hearing impairment in the aged. AB - Ageing affects all parts of the ear. The effect on the inner ear and its central connections is the most important cause of presbyacusis and contributes maximally to communication difficulties faced by the aged. A number of studies have been conducted on prevalence of presbyacusis. A prevalence of 3.7 to 3.3 per cent was found in the general populations surveyed in rural and urban areas respectively. There is hardly any systematic arrangement available for rehabilitation and fitting of hearing aid as an organized facility. Further research is needed to develop better quality hearing aids which will fully satisfy the needs of the aged. PMID- 9361467 TI - Nutritional status of the elderly. AB - Elderly become vulnerable to malnutrition owing to inappropriate dietary intake, poor economic status and social deprivation. Elderly are known to be easily subjected to inanition and avitaminosis resulting in multiple nutritional deficiencies. Urban slum dwellers, rural poor and those living alone appear to be at a higher risk of poor dietary intake. Though food consumption patterns of rural and urban elderly show a distinct difference, these are greatly influenced by regional dietary patterns. The diets of institutionalised and free living elderly reveal adequate nutrient intakes except iron and vitamin A. The nutrients least adequately supplied in the diets of Indian elderly are calcium, Iron, vitamin A, riboflavin and niacin along with energy deficits. Changes in body composition which mark the onset of the ageing process, include decline in lean body mass and increase in adipose tissue. A high prevalence of iron deficiency anaemia has also been reported among Indian elderly. PMID- 9361468 TI - Socio-economic status & its relationship to morbidity among elderly. AB - This paper seeks to review the current state of art in the area of morbidity and the socio-economic status of the elderly in India and the relationship between the two. It is concerned primarily with research on social factors, illness and its relationship. It has the following concerns: (i) conceptualisation of morbidity, illness, disease and mortality; (ii) the nature of illness, disease; (iii) quantum of disease and; (iv) how variations in the rates of diseases are related to social characteristics. Available evidence from past and contemporary studies indicate that a large number of factors tend to affect morbidity among the elderly. PMID- 9361469 TI - Psychiatric morbidity in the aged. AB - Mental morbidity in the elderly comprises mainly affective disorders (manic depressive psychosis) and psycho-organic syndrome, delirium and dementia. Psychiatric disorder occurs with physical disorder or handicap and co-morbidity is the hall-mark of geriatric medicine. The prevalence rate is around 89/1000 population. The decreasing age at onset of depression over successive generations contributed by the 'unstable genes' is discussed. Factors affecting the 'quality ageing' are highlighted. Depression, mania and suicide behaviour in the elderly are detailed. Particular attention is drawn to 'vascular depression' resulting from cerebrovascular lesions affecting the striato-pallido-thalamo-cortico pathways. Vascular depression is characterised by a low frequency of family history of mental disorder/suicide and anhedonia and increased functional disability. Subsyndomal depression is a fairly common occurrence. Anxiety disorders in the elderly though uncommon need to be recognised. Late-onset schizophrenia and somatic hallucinosis are referred to. PMID- 9361470 TI - Intergenerational solidarity. AB - Family is that thread which links multiple generations together through a system of shared beliefs, norms, values and cultural traditions. Intergenerational ties fulfil many functions within a family. Besides transmission of appropriate information regarding behaviour, life styles, and values, these ties help reduce marginalization between different generations, and are a source of support and identity for each individual. The knowledge of ageing and the development of positive attitudes towards old age contribute to the improvement of intergenerational relations, combat stereotypes that promote ageism and develop a more realistic outlook towards one's own ageing process. PMID- 9361471 TI - Coping with ageing. AB - Old age is the last stage in the life span and with the change from middle age to old age it envisages a series of adjustments, in behaviour and thinking to meet the demands of a waning existence punctuated by disease, disability and disbelief. Central to coping with personal ageing is the acceptance of its reality. Happy ageing consists of adjusting to the demands of the stage and using the time and resource available beneficially to oneself and others. The role of maintaining good physical and mental health and cultivating appropriate attitudes towards it, is a requirement that can hardly be overstressed. Empirical studies have shown the significant contribution of several variables to successful ageing. PMID- 9361472 TI - Stress dimensions among caregivers of the elderly. AB - Urbanisation, nuclearisation of family, migration and dual career families are making elder care more and more of a personal and social problem in India. Increasing life span and poor health care add to the degree of disability among the elderly and compound the problems of caregiving. The caregiver, who is usually a spouse or the daughter-in-law in an Indian family find it increasingly stressful to meet the care needs of disabled and frail elderly in the family. With the prospect of this situation worsening in the coming decades, ways and means need to be examined of managing the stress effectively. There is a growing need for interventions not only to manage the stress of caregiving but also to ensure the mental health of this vulnerable group and to evolve a policy to meet the care/needs of disabled elderly. PMID- 9361473 TI - The abused elderly. AB - The world has now focussed its attention on the aged as they are growing in numbers. Many developed countries have provided various patterns of care processes for the elderly. India too is feeling the impact of ageing population and is trying to cope with the demands of this population. Various problems have to be faced by the ageing population and one of them is the abuse of the elderly. This abuse is overt or covert and in different areas of their life style, that is economic, social or religious and occurs in daily life patterns. Often the abuse could also be included in legal patterns of transactions between the aged and their relatives. Because the aged are a surplus or the greying population they are helpless and unable to combat these situations. Stereotypes also work against the aged. It is therefore necessary to make aged legally literate and allow them to live in dignity. PMID- 9361474 TI - Women & ageing. AB - Demographic changes have forced gerontologists to focus attention on the gender based character of population ageing. Ageing is likely to become a 'gender issue' with a large number of women surviving into very old age in almost all the countries of the world. Elderly women, especially in Third World countries like India, face several jeopardizes. They are likely to be illiterate or poorly educated, unlikely to be employed, most likely to be widowed and dependent on others, and they suffer from malnutrition and disabilitating symptoms as well as report higher psychological distress. The vulnerability of the ageing women, special types of problems they are likely to encounter over the life span, and factors that marginalise them need to be better understood. There is no clear awareness as yet, of the potential contribution of ageing women to the development process as ageing women are stereotypically perceived as burdens on the national economy. Strategies addressed to ensure health and well-being of older women need to be developed. PMID- 9361475 TI - Old-age homes & the profile of their residents. AB - Studies conducted on old-age homes and their inmates are reviewed. Though institutionalization of the elderly is a new phenomenon in India, a number of old age homes have come up and there is a need for many more homes in India. Investigations with regard to the status of the aged in the changing social structure have more or less concluded on the breaking down of kinship and family organisations which has put the elderly in a state of helplessness, isolation and economic dependence. PMID- 9361476 TI - Molecular biology of ageing. AB - The process of deterioration or ageing of functions that occurs in all organisms after the attainment of reproductive ability is the sum total of the decline in activity of various organs. The functions of different organs begin to deteriorate at different times of the life span and at different rates. It is believed that different genes are involved in the ageing of different organs. Studies on isoenzyme patterns of enzymes show that the genes responsible for coding of different subunits of the enzymes are sequentially expressed during the life span. Also, the decrease in the levels of enzymes seen after adulthood is reversible and can be raised to adult level by inducing their genes by steroid hormones. Another factor that contributes to the decrease in the levels of enzymes is increasing compaction of the chromatin that houses the genes as seen from digestion of chromatin by DNase I and MNase. This decreases the rate of transcription of genes. The expression of many genes declines after adulthood which is due to the decrease in trans-acting nuclear proteins that bind to specific cis-acting sequences in the promoter regions of genes. These proteins are inducible by steroid hormones. Hence the deterioration of functions that occurs after adulthood can be delayed, and the adulthood period can by prolonged by manipulation of the expression of genes. PMID- 9361477 TI - DNA-damage & DNA-repair in ageing brain. AB - The validity of DNA damage and repair hypothesis of ageing has been examined with special reference to the brain. As far as the accumulation of DNA damage is concerned, the data appear to overwhelmingly support the hypothesis. However, the results of attempts to demonstrate a decline in DNA repair capacity as a function of age are conflicting. However, more recent observations are in support of age dependent deterioration in DNA-repair capacity. Possible reasons for this discrepancy and the usefulness of conducting DNA damage and repair studies in a model system of isolated neuronal cells, are discussed. It is suggested that assessment of repair capacity of brain with respect to a specific damage in a designated gene might yield more definitive answers regarding the role of DNA repair potential in the ageing process and as a longevity assurance system. PMID- 9361479 TI - Assisted suicide and equal protection: in defense of the distinction between killing and letting die. AB - The author argues that the distinction between intentionally killing oneself and intentionally letting oneself die is both coherent "as a matter of principle" and morally relevant. This principled distinction then provides a benchmark for courts considering equal protection arguments to distinguish one patient seeking to commit suicide from another wishing to free herself of unwanted life sustaining medical treatment, and to conclude that these two individuals are not similarly situated for purposes of the Equal Protection Clause. These two situations are morally distinct--the deaths are caused by different means and those involved have different intentions. The intention of the doctor and patient to hasten the patient's death is material, and the intention relates to understanding what it means to treat people equally. Doctors who participate in assisted suicide intend their patients to die by their own acts, i.e., intentional killing. The author concludes that those who ask their doctors to commit assisted suicide and those who forego treatment are not similarly situated for purposes of the Equal Protection Clause. The afterward comments on the Supreme Court's recent assisted suicide decision. It affirms the author's analysis. PMID- 9361478 TI - Perinatal hospice: a response to partial birth abortion for infants with congenital defects. AB - This article discusses decisions involving whether to terminate late-term pregnancies when fetal anomalies have been detected. Partial-birth abortion performed on fetuses with chromosomal abnormalities, while performed under the guise of reducing suffering, threatens the best interests of the mother and infant. An alternative for parents faced with the decision to terminate their pregnancy is perinatal hospice. Perinatal hospice recognizes the value of bringing these infants to term by treating them as beings conceived with a tangible future. This alternative is preferred because of post-termination psychological distress and because biblical teachings emphasize the dignity and worth of each fetus. Perinatal hospice supports parents through their grief when their infant dies and maximizes the opportunity for authentic mourning. PMID- 9361480 TI - The Model Physician-Assisted Suicide Act and the jurisprudence of death. AB - A Model Statute to Authorize and Regulate Physician-Assisted Suicide was published in 1996. This article describes the Act and some of its background and effects in detail, showing that it goes further than at first appears. Specifically, the article discusses the background and basic effect of the Act, the principal provisions of the Act and their effects, the morality and jurisprudence of the Act, the argument from autonomy, and the argument from utility. The authors conclude that by ignoring the moral traditions of Western culture, and focusing only on the ethics and anthropology of autonomy and utility, the drafters of the Act justify the dehumanization of the very people the Act is supposed to benefit. PMID- 9361481 TI - A model state Act to authorize and regulate physician-assisted suicide. PMID- 9361482 TI - Postgraduate medical education in U.K. and Pakistan. PMID- 9361483 TI - Ultrastructure of the May-Hegglin anomaly. AB - Ultrastructural features of the leucocytes in two patients suffering from the May Hegglin anomaly were studied using electron microscopy. In both the cases, electron dense material parallel to the long axis of the inclusions were noted. Platelet ultrastructure was normal. A review of the literature indicates that the May-Hegglin anomaly is a heterogeneous condition both ultrastructurally and clinically. PMID- 9361484 TI - Fluorescent antinuclear antibody and anti-double-stranded DNA antibody testing: a four years experience. AB - Fluorescent antinuclear antibody test (FANA) and anti-double stranded deoxytribonucleic acid (dsDNA) antibody testing is an integral part of the evaluation of the patients who are suspected of having connective tissue disease. We tested 2,140 serum samples for FANA and 1,460 serum samples for anti-dsDNA antibodies. Of 2,140 serum samples tested for FANA, 492 (23%) yielded a positive result (titre of 1:80 or greater) and of 1,460 serum samples tested for anti dsDNA, 69 (4.7%) yielded positive results. Highest number (n = 27) of serum samples positive for anti-dsDNA antibodies were found in serum samples that were positive for FANA test at a titre of 1:1280 or greater. In conclusion, FANA test can be used as an initial screening test for connective tissue/autoimmune disorders. PMID- 9361485 TI - Low dose, short-term, triple therapy for helicobacter pylori associated peptic ulcer. AB - To confirm the efficacy and tolerability of a new, low-dose, short-term triple therapy, 31 endoscopically diagnosed cases of peptic ulcer who were helicobacter pylori positive by brush cytology and urease test were inducted into the study. These patients were given lansoprazole 30 mg once a day, clarithromycin 250 mg twice a day and tinidazole 500 mg twice a day for one week only. Endoscopy, urease test and methylene blue test for helicobacter pylori were repeated four weeks after stopping the therapy. Ulcer healed in all the patients while helicobacter was eradicated in 90.3% of patients. PMID- 9361487 TI - The postgraduate medical education in U.K.--the system and its relevance to training and medical practice in Pakistan. PMID- 9361486 TI - Thrombocytopenia in preeclampsia: an earlier detector of HELLP syndrome. AB - Platelet count was determined in eighty four pregnant women by direct visual method. Among them thirty normal pregnant women were taken as control. Twenty seven were preeclamptic and twenty seven eclamptic women. There was significant (P < 0.01) reduction in platelet count of preeclamptic and highly significant (P < 0.001) in eclamptic women as compared to controls. It is concluded that there is need to do platelet count in all pregnancy induced hypertensive women, which can be an earlier detector for HELLP syndrome. PMID- 9361488 TI - Gingival hypertrophy in acute megakaryoblastic leukemia. PMID- 9361489 TI - Congenital mesoblastic nephroma. PMID- 9361490 TI - Iodine deficiency disorders: myth or reality. PMID- 9361492 TI - Agenesis of the corpus callosum and chorioretinal lacunae. Aicardi's syndrome. AB - Aicardi's syndrome is the association of three main features: infantile spasms, chorioretinopathia with lacunae and agenesis of the corpus callosum. Four female infants are presented and comments on the possible etiopathogenesis is done. PMID- 9361491 TI - The role of HBV-infection in development of cataracts in children and adults. AB - Possible role of intrauterine HBV infection in the formation of congenital non hereditary cataracts is testified by discoveries of HBV markers in lens masses, aqueous humor of the anterior chamber and blood serum of the operated children and in blood of mother. We consider the patients with chronic diffuse liver diseases of HBV etiology to be a risk group of post capsular cataracts' formation. The development of these cataracts is associated with the progress of the basic liver disease. Among practically healthy persons, the initial lens changes are more often observed in carriers of australian antigen. Early signs of lens diseases in children and young or middle-aged adults determine the social meaning of this problem and reasons for the regular ophthalmologic check-up of patients with virus liver diseases and somatically healthy virus carriers. PMID- 9361493 TI - A comparison of prevalence rates of genital ulcers among persons attending a sexually transmitted disease clinic in Jamaica. AB - Two cross-sectional surveys were undertaken, from December 1982 to August 1983 and from November 1990 to January 1991, to estimate the prevalence rates of genital ulcer disease (GUD) in all patients presenting with a new sexually transmitted disease (STD) complaint to the STD clinic at the Comprehensive Health Centre in Kingston, Jamaica. Diagnosis of syphilis and human immunodeficiency virus (HIV) infection was based on results of laboratory tests, but diagnosis of the other STDs was based on clinical features. Data from these two surveys were compared, and reported national annual incidence data for GUD reviewed. In 1982/83 6.8% of 23,050 patients had GUD, men (9.3%) more often than women (4.2%; p < 0.001). In 1990/91 the prevalence rate was 12.8%, with increased rates for both men (18.2%) and women (6.8%; p < 0.001). In patients with GUD, a clinical diagnosis of genital herpes was made, in 1982/83 and 1990/91, respectively, in 16.8% and 7.8% of the patients; syphilis, in 12.9% and 18.8%; chancroid, in 12.4% and 13.3%; viral warts, in 5.7% and 6.3%; lymphogranuloma venereum, in 4.1% and 3.9%; and granuloma inguinale, in 3.6% and 2.3%. In men the rate for syphilis was 19% in 1990/91 and 8% in 1982/83 (p = 0.001); and for genital herpes it was 7% in 1990/91 and 17% in 1982/83 (p = 0.025). These reversals were attributed to intense media coverage of herpes in 1982/83. There was no difference in prevalence rates between the two surveys for these diseases in women, or for lymphogranuloma venereum, granuloma inguinale and genital warts in men and women. A clinical diagnosis could not be made in 44.4% of cases in 1982/83 (particularly in men), and in 47.6% of cases in 1990/91. GUDs facilitate transmission and adversely affect the prognosis of HIV. The increase in their prevalence has implications for the evolution of the local HIV epidemic, and should be addressed effectively by strengthening the STD/HIV control programme. PMID- 9361494 TI - The age-prevalence profile of abdominal obesity among patients in a diabetes referral clinic in Jamaica. AB - Generalised obesity is a major risk factor for cardiovascular disease, diabetes, hypertension and premature death, but abdominal or central obesity is even more closely related to these. Diabetes causes accelerated atherosclerosis and this results in peripheral vascular and ischaemic heart disease and stroke, major causes of death in diabetics in the Caribbean. Diabetics who have abdominal obesity are therefore at increased risk for these events. 485 patients attending the Diabetes Referral Clinic at the University Hospital of the West Indies, Jamaica, were evaluated for abdominal obesity based on the ratio between their waist and hip measurements. There was an increase in the numbers of diabetics with increasing age. Abdominal obesity was significantly more prevalent among females (90%) than among males (34.9%) (mean 2 = 142; p < 0.0001), and massive obesity was detected in 31.1% of females. However, the prevalence of abdominal obesity among males and females was not significantly age-related. Given the high prevalence of obesity in this clinic population, more precise studies of abdominal obesity associated morbidity in diabetics should be undertaken. PMID- 9361496 TI - The pathology of thyroid neoplasms at the University Hospital of the West Indies. A 10-year analysis. AB - Thyroid neoplasms were diagnosed in 93 patients (79 women and 14 men) between January 1986 and December 1995. 52 tumours were benign and 41 were malignant. An unusual finding was that there were 16 cases each of follicular and papillary carcinomas; that is, more patients with follicular carcinomas than expected. The significance is discussed. PMID- 9361495 TI - Myocardial infarction in Antigua. 1990 to 1995. AB - Between January 1990 and May 1995, 117 patients were admitted to the Intensive Care Unit at Holberton Hospital, Antigua, for chest pain due to suspected acute myocardial infarction. 39 (45%) of 86 patients whose records were available for retrospective review had confirmed (27 patients) or probable (12 patients) acute myocardial infarction. Risk factors identified among the patients included hypertension, diabetes, tobacco smoking, hypercholesterolaemia and obesity. On admission, 82% were Killip class I and 18% were Killip class II. Medications in the Intensive Care Unit included nitrates, aspirin, calcium channel blockers, beta-adrenergic blockers, heparin and angiotensin converting enzyme inhibitors (21%). No thrombolytic agents were available. The average hospital stay was 10 days and the in-hospital mortality rate was 13%. These data indicate that early mortality from acute myocardial infarction can be reduced in developing countries by early admission to an Intensive Care Unit and use of drugs known to be effective in its treatment. PMID- 9361497 TI - Experience of parents of children with disabilities with health services in Jamaica. AB - In order to determine the experiences with health services of caregivers of children with disabilities (CWDs), and the attitudes of health care workers (HCWs) towards CWDs and their caregivers, a survey was conducted of 26 caregivers of clients of 3D Projects, St. Mary, Jamaica, using a checklist, and of 113 HCWs in St Mary and Kingston who completed a questionnaire. Half of the 19 CWDs referred by HCWs to hospitals in Kingston because of the lack of facilities in St Mary eventually defaulted because there was no apparent improvement. 10 caregivers said that the cause of the disability was not explained, three others did not understand the explanation given, and only 4 understood the instructions of HCWs. These problems led to unrealistic expectations about the outcome of rehabilitation. 13 caregivers attributed disability of their CWDs to negligence, carelessness or poor treatment by HCWs during pregnancy or the early neonatal period. 87% of the HCWs, particularly Community Health Aides (CHAs), acknowledged at least some responsibility for the care of CWDs; but 10%, notably some nurses and midwives, denied responsibility. 90% referred patients for further care and 90% thought that they had made an impact on caregivers' 'beliefs'; but more than half the CHAs, and 25 to 30% of the other groups, expressed dissatisfaction with their management of CWDs. This study has highlighted inadequacies in the care of CWDs in St Mary and indicates that more appropriate preparation of all health staff for this important aspect of their work is required. PMID- 9361498 TI - Medical practitioners' views on the management of hypertension in Trinidad and Tobago. AB - We surveyed 161 medical practitioners in Trinidad and Tobago (124 reporting private sector practice and 37 describing government health centre practice) for their views on blood pressure (BP) management. 96% of the respondents agreed that BP should be measured on all adults seen and 90% agreed that diastolic pressure should be recorded as the disappearance of sounds. There was disagreement over the level of diastolic BP at which drug treatment should be initiated: 63% would treat diastolic BP less than 100 mm Hg, but 35% would only treat diastolic BP of 110 mm Hg or higher. In private practice 31% preferred angiotensin converting enzyme (ACE) inhibitors as treatment for an African Caribbean man with diastolic BP 110 mm Hg, but in public clinics 41% preferred thiazide diuretics. ACE inhibitors were most often preferred as treatment for an Indo-Caribbean man with diabetes and diastolic BP 110 mm Hg in both public and private practice. Doctors considered that noncompliance (66%), lack of education (34%) and unhealthy lifestyles (25%) were important obstacles to BP control. In private practice doctors considered patients' financial constraints to be an obstacle (58%), whereas in the public sector limited availability of drugs (57%) was felt to be more important. Less costly and, possibly, more appropriate drugs were used in public clinics. PMID- 9361499 TI - Examination performance of medical students. A view from Trinidad. AB - We analysed the outcome of the final MBBS (Bachelor of Medicine and Bachelor of Surgery) examinations at the St. Augustine Campus, University of the West Indies, for 686 students attempting them for the first time between 1975 and 1986. The mean failure rate was lowest in Medicine between 1975 and 1981, in Obstetrics & Gynaecology between 1982 and 1989 and in Surgery during the last 7 years. The students' poor performance in some areas indicates the need for recognizing the importance of creating and establishing an educational climate in which the quality of teaching comes under scrutiny. The marking system in Medicine should be reviewed. PMID- 9361500 TI - Autoimmune haemolytic anaemia, immune thrombocytopenia, and leucopenia. An unusual presentation of Hodgkin's disease. AB - We report an unusual case of nodular sclerosing Hodgkin's Disease in a 17-year old woman presenting with intermittent fever, progressive weight loss and enlarged cervical and axillary lymph nodes. Laboratory tests revealed severe Coombs' positive haemolytic anaemia, and progressive thrombocytopenia and leucopenia, associated with erythroid, myeloid and megakaryocytic hyperplasia, but with no evidence of lymphomatous infiltration in the bone marrow. Transfusion of compatible blood became possible only after prednisone therapy and a single intravenous dose of vincristine. Appropriate chemotherapy led to normalization of the peripheral blood counts and a negative direct Coombs' test. PMID- 9361501 TI - Evolving status of xenotransplantation: introduction. PMID- 9361502 TI - Xenoantigens and xenoantibodies: their modification. AB - The hyperacute rejection of pig organs by primates, including humans, results from antibody-mediated complement activation. Protection from complement injury still leads to delayed rejection, which results from other mechanisms that may also be dependent on the presence of antibody. Anti-pig antibodies are directed largely, if not entirely, against alpha-galactose (alpha Gal) epitopes on pig vascular endothelium. Prevention of antibody-antigen binding is being attempted by methods that (1) alter antigen expression on the donor organ or (2) deplete the potential recipient of anti-alpha Gal antibody. To date, most progress has been made in depleting antibody by extracorporeal immunoadsorption using immunoaffinity columns of synthetic alpha Gal oligosaccharides. A pig organ transplanted into a recipient baboon depleted of antibody functions for several days--in contrast to minutes to hours in unmodified baboons. The return of antibody, however, results in rejection of the graft. Pharmacologic immunosuppressive agents are relatively ineffective for prolonged suppression of anti-alpha Gal production. Total-body irradiation and splenectomy are proving more successful. Studies are continuing with the aim of achieving a state of B cell tolerance toward alpha Gal epitopes. PMID- 9361503 TI - Complement activation, its consequences, and blockade by gene transfer. AB - The success of xenotransplanting vascularized pig organs into humans is limited owing to the immediate immune reaction, termed hyperacute rejection (HAR). This reaction is primarily mediated by naturally occurring xenoreactive antibodies binding to the graft and activating the complement system, resulting in organ dysfunction. Pig membrane-bound complement regulatory proteins efficiently control autologous complement only and are unable to protect against human complement-mediated damage. One line of current research to overcome HAR of pig organs involves the expression of human complement regulatory proteins by pig cells. In vitro data have demonstrated that pig endothelial cells expressing human regulators of complement activation (RCAs) are resistant to human complement-mediated attack, which has led to the successful production of pigs transgenic for human RCAs. Ex vivo perfusion studies using fresh human blood with organs from these animals has shown an improvement in graft function and survival through expression of human RCAs compared to that of nontransgenic pig organs. Similar results have been observed in primate models, where expression of human RCA proteins on the pig donor organ has resulted in protection against HAR and prolongation of graft survival. The initial complement-mediated immunologic barrier of HAR has been overcome through this genetic incorporation of human RCAs into pigs, and it is now possible to study the subsequent mechanisms of xenograft rejection in the pig-to-human combination. PMID- 9361504 TI - Genetic engineering as an approach to xenotransplantation. AB - A discordant organ xenograft, such as a heart or kidney transplanted from pig to human, is rejected within 1 to 2 hours by a process called hyperacute rejection (HAR) caused in large or full measure by preexisting host xenoreactive natural antibodies (XNAs) and complement. HAR can be averted by blocking either complement or XNAs; but the xenograft is then rejected at 3 to 4 days by a process called delayed xenograft rejection (DXR), which can occur without the presence of T cells. DXR involves type II endothelial cell (EC) activation (the phase of activation that includes up-regulation of proinflammatory genes in the EC), infiltration into the graft of host monocytes and natural killer cells (both of which appear to be activated), and a complex cytokine picture. We discuss in this paper various approaches that might help prevent DXR, after which we assume that one would still have to deal with a xenograft counterpart of the T cell mediated allograft rejection response. The approach to avoiding DXR focuses largely on genetic engineering of the ECs in the graft. PMID- 9361505 TI - Delayed xenograft rejection. AB - The triumph of genetic engineering in overcoming hyperacute rejection (HAR) of a discordant organ xenograft is clear, but the promise of clinical application of xenotransplantation remains unfulfilled as further immunologic barriers are defined that lead to rejection of a vascularized xenograft within days of transplantation. This report describes the features of this second set of immunologic responses, collectively termed delayed xenograft rejection (DXR). DXR is a syndrome seen in xenograft recipients in which HAR has been avoided or suppressed by antibody depletion or blockade of complement activation. DXR may result, at least in part, from the persisting activation of those pathways first encountered during the HAR phase. Serial studies over several days after transplant show that, histologically, xenografts undergoing DXR demonstrate varying combinations of (1) progressive infiltration by activated macrophages and natural killer (NK) cells, (2) platelet aggregation and fibrin deposition throughout the microvasculature, and (3) endothelial activation. In various experimental models, DXR is T cell-independent and can occur in the absence of demonstrable xenoreactive antibodies. Hence DXR is probably best regarded as arising from the activation of innate host defense mechanisms coupled with failure of normal regulatory mechanisms due to manifold molecular incompatibilities. Although DXR-like features can be seen in concordant models, T cell involvement in the latter is probably requisite. Similarly, in a much muted form, aspects of a DXR-like process may contribute to numerous inflammatory processes, including allograft rejection. The importance of DXR in xenotransplantation is that its development appears resistant to all but the most dense and toxic forms of immunosuppression, which prolong xenograft survival at the expense of inducing host leukopenia, thrombocytopenia, and coagulopathies. It is likely that until the basis of DXR is more clearly understood there can be no further significant progress toward clinical xenotransplantation. However, as the mechanisms responsible for DXR are dissected and understood, still further genetic engineering of donor pigs, involving the introduction of additional or multiple genes to regulate macrophage and NK cell responses, local coagulation, and endothelial cell activation, may once again prove to be an attractive, practical, powerful therapeutic option. PMID- 9361506 TI - Immature host for xenotransplantation. AB - The overall shortage of appropriate donor organs has prompted transplant physicians and surgeons to consider using organs from other nonhuman species. The shortage of appropriate human donor hearts for newborn recipients is especially severe. Presently, the pig appears to be the most appropriate source for organs. Humans and baboons uniformly develop high titers of complement-fixing (IgM) anti pig xenoantibodies, resulting in complement-mediated hyperacute rejection (HAR) of pig organs transplanted into mature baboons within minutes to hours. In contrast, newborn humans and baboons do not have high titers of anti-pig IgM xenoantibody, and consequently pig cardiac xenografts transplanted into newborn baboons do not undergo HAR. Rather, these organs are rejected at days 3 to 4 by a distinctive immunologic process that involves natural killer cells and macrophages. With the addition of cyclosporine-based triple immunosuppression, this process is reduced and graft life is prolonged to 6 to 7 days. This therapy, however, is not sufficient to prevent the induced humoral response to the graft, and the organs are rejected by antibody- and complement-dependent mechanisms. Future treatment strategies to reduce this humoral response must incorporate immunodepletion columns, soluble complement-inhibiting agents, and additional anti-B lymphocyte agents. These strategies, in conjunction with the use of transgenic pig organs that express human membrane-bound complement regulatory proteins or reduced xenoantigenic epitopes could further prolong graft life. Clinical trials are being formulated that would utilize pig organs as a "bridge," sustaining a newborn human in need of a heart transplant until an appropriate donor is located. PMID- 9361508 TI - Genetically modified animal organs for human transplantation. AB - The major barrier to successful discordant xenogeneic organ transplantation is the phenomenon of hyperacute rejection (HAR). Hyperacute rejection results from the deposition of high-titer preformed antibodies that activate serum complement on the luminal surface of the vascular endothelium, leading to vessel occlusion and graft failure within minutes to hours. Here we describe our strategy to overcome HAR in the pig-to-primate transplant setting, which includes the genetic incorporation into transgenic organs and high level expression of both a novel human bifunctional complement inhibitor and a human blood group enzyme. The expression of the human blood group enzyme is designed to reduce significantly the natural antibody reactivity to the discordant pig tissue, whereas expression of the complement inhibitor results in inhibition of complement-mediated cell activation and lysis. High-level cell surface expression of the complement inhibitor and high-level expression of the human blood group enzyme in vascular endothelium effectively eliminate both the antibody and complement components of the massive inflammatory response to the xenogeneic tissue. Elimination of HAR will establish inroads into understanding the cellular immune response toward the discordant tissue. It is conceivable that standard immunosuppressive regimens routinely practiced with allotransplantation can also be effective drug therapies for xenotransplantation. Therefore it is critical to develop a system that tests these possibilities in order to solve an ever-growing need for donor organs. PMID- 9361507 TI - Tolerance induction for xenotransplantation. AB - The transplantation of donor hematopoietic tissue prior to organ xenografting has the potential to induce lasting T cell tolerance and, possibly, tolerance of natural antibody-producing B cells. However, the development of specific and nontoxic methods of overcoming the immunologic and physiologic barriers to xenogeneic marrow engraftment is a major challenge that must be met before this goal can be achieved. A greater understanding of the species specificity of molecular interactions important for hematopoiesis and cell homing is a first step toward transcending these physiologic barriers. Perhaps most promising is the potential associated with the use of nonprimate xenogeneic donors genetically engineered to make donor tissues more readily capable of surviving and, in the case of hematopoietic cells, competing with host tissues for survival in a human environment. PMID- 9361509 TI - Survival following orthotopic cardiac xenotransplantation between juvenile baboon recipients and concordant and discordant donor species: foundation for clinical trials. AB - It has been more than a decade since the last clinical trial of cardiac xenotransplantation in a newborn infant. Since that event, laboratory research at Loma Linda University has focused on survival studies of orthotopically xenografted juvenile baboon recipients. Both concordant and discordant donor species have been used. Transgenic donors have not been explored at Loma Linda. Instead, simplified host immunoregulative protocols, consistent with those used in neonatal cardiac allografting, have been adapted to xenotransplant research. Xenograft bridge to alloengraftment was evaluated in a series of five juvenile baboon recipients. Heterotopically implanted cardiac xenografts stimulated host production of xenoreactive antibody. Orthotopic cardiac allografting was then carried out. Xenoantibody appeared to play little role in immediate or chronic survival of experimental hosts. A clinical protocol of xenobridging to allotransplantation would likely succeed. Two consecutive series of orthotopically xenotransplanted hosts using rhesus monkey cardiac donors demonstrated unprecedented long-term survival. Splenectomy combined with maintenance therapy consisting of FK-506 and methotrexate contributed to survival of up to 502 days in one series of xenografted baboon hosts selected for ABO blood grouping, mixed lymphocyte culture, and crossmatch compatibility. Survival beyond a year (maximum 515 days) among three consecutive juvenile baboon recipients of orthotopically implanted rhesus monkey hearts, in which splenectomy was omitted and cyclosporine was substituted for FK-506, represents a benchmark achievement. Commencing maintenance immunosuppression several weeks prior to transplantation appeared to improve chronic survival significantly. Investigation of discordant (pig-to-baboon) host survival has focused on adsorption of naturally occurring xenoreactive antibody at the time of transplantation. This strategy, combined with pretransplant total lymphoid irradiation and both pre- and posttransplant immunosuppression, succeeded in preventing hyperacute rejection and resulted in survival of up to 24 days, thereby permitting observation of the delayed xenograft rejection phase. Data support consideration of additional clinical trials of concordant neonatal cardiac xenotransplantation and offer promise for the development of discordant xenotransplantation as an ultimate therapeutic resource. PMID- 9361510 TI - Laboratory studies in cross-species lung transplantation. AB - The lack of sufficient suitable human donor lungs for the many patients requiring pulmonary transplantation as life-saving therapy for end-stage lung diseases has generated extensive interest in cross-species lung transplantation. Ethical concerns and those of animal rights advocates have prompted studies of nonprimate species as potential solid organ donors for humans. This paper provides an overview of some of the laboratory studies of cross-species pulmonary transplantation performed over the past 20 years and focuses, in particular, on more recent work (from our laboratory and others) in the area of porcine-to primate pulmonary xenotransplantation. PMID- 9361512 TI - Baboon bone marrow transplantation in humans: application of cross-species disease resistance. AB - Xenotransplantation is a newly evolving field. A renewed interest has emerged coincidentally with the shortage of donor organs for transplantation. Bone marrow (BM) chimerism has been suggested as a potential strategy to induce tolerance to xenografts and control the immune response across a species barrier. Bone marrow transplantation (BMTx) displays unique features compared to solid-organ transplantation or transplantation of other cellular grafts. To achieve engraftment of the pluripotent hematopoietic stem cell, which generates all lineages of the hematolymphopoietic system, conditioning of the recipient (usually a combination of irradiation and cytoablative chemotherapy) is required. Once engraftment is achieved, graft function is stable and rejection does not occur, even without immunosuppression. On the other hand, the graft itself is able to generate an immune response against the host, resulting in graft-versus host disease (GVHD). A newly recognized advantage to xenotransplantation is species-specific disease resistance. In terms of BMTx, important questions arise: Can xenogeneic BM generate a competent immune response across species barriers? Will cross-species GVHD occur? What are the possible applications to humans? This review addresses these questions. Problems emerging from xenogeneic BMTx are summarized and strategies for their solution discussed. PMID- 9361511 TI - Clinical trials and projected future of liver xenotransplantation. AB - The trial and error of the pioneering xenotransplant trials over the past three decades has defined the limitation of the species used. Success was tantalizingly close with the chimpanzee, baboon, and other primates. The use of more disparate species has been frustrated by the xenoantibody barrier. Future attempts at clinical xenotransplantation will be hampered by the consideration of the species of animals and the nature of the organs to be transplanted. On one hand, primate donors have the advantage of genetic similarity (and therefore potential compatibility) and less risk of immunologic loss. On the other hand, pig donors are more easily raised, are not sentient animals, and may be less likely to harbor transmissible disease. It is recognized that the success of xenotransplantation may very with different organs. Because it is relatively resistant to antibody-mediated rejection, the liver is the organ for which there is the greatest chance of long-term success. Consideration of using xenotransplants on a temporary basis, or as a "bridge" to permanent human transplantation, may allow clinical trials utilizing hearts or kidney xenografts. Issues on metabolic compatibility and infection risks cannot be accurately determined until routine success in clinical xenotransplantation occurs. Based on a limited experience, the conventional approaches to allotransplantation are unlikely to be successful in xenotransplantation. The avoidance of immediate xenograft destruction by hyperacute rejection, achieved using transgenic animals bearing human complement regulatory proteins or modulating the antigenic target on the donor organ, is the first step to successful xenotransplantation. The ability to achieve tolerance by establishing a state of bone marrow chimerism is the key to overcoming the long-term immunologic insults and avoiding the necessarily high doses of nonspecific immunosuppression that would otherwise be required and associated with a high risk of infections complications. Xenotransplantation faces criticism that is strongly reminiscent of that leveled against human-to-human transplantation during the late 1960s and early 1970s. Yet with persistence, the field of human-to-human transplantation has proved highly successful. This success was the result of a stepwise increase in our understanding of the biology of rejection, improvements in drug management, and experience. It is possible that xenotransplantation may not be universally successful until further technologic advances occur; yet cautions exploration of xenotransplantation appears warranted to identify those areas that require further study. PMID- 9361513 TI - Infectious concerns of cross-species transplantation: xenozoonoses. AB - Xenotransplantation is a potential solution to the current donor shortage for allotransplantation. Likewise it is being investigated for a number of other disease states such as Parkinson's disease, diabetes, and acquired immunodeficiency disease. Infections are a concern with the use of any biologic agent and as such have proved to be a substantial cause of morbidity and mortality after allotransplantation. Similarly, infections will likely cause disease after xenotransplantation. Public debate on the ethics of whether the field of xenotransplantation should move forward has focused on the concern of novel infections, xenozoonoses. Accordingly, the role of animal microbes must be critically examined. This article reviews mechanisms for xenogeneic infections and details what is known and what still needs to be learned as the field of xenotransplantation progresses. Emphasis is placed on microbial agents of baboons and swine, as they are currently the most common species considered as donor sources for xenotransplantation. PMID- 9361514 TI - Ethics of xenotransplantation: animal issues, consent, and likely transformation of transplant ethics. AB - The shortage of organs, breakthroughs in research, involvement of biotechnology companies, absence of ethically more acceptable alternatives, and a vaguely perceived "time to put man on the moon" feeling have contributed to the current reawakening of interest in xenotransplantation. The focus of ethical attention has changed from the moral correctness of using animals for research/therapy to an increasingly appreciated danger of the establishment and spread of xenozoonoses in recipients, their contacts, and the general public. The United Kingdom has established an embargo on clinical trials and has set up a national regulatory authority to oversee and coordinate the development of research, establish guidelines, and decide on when trials can proceed. In the United States, on the other hand, the overall attitude is to "proceed with caution," and the Food and Drug Administration has approved a number of xenotransplant studies. The Public Health Service guidelines on reducing infection risk are still evolving and are likely to end up being more cautions than they are currently. There are a number of reasons for not using subhuman primates for xenotransplantation, including their closeness to humans, the likelihood of passing on infections, their depletability (gorillas, chimpanzees), their slow breeding, and the expense of breeding them under specified-pathogen free conditions. The pig, although domesticated and familiar, is too distant to evoke the same feelings we have for primates, has the correct-size organs, is probably less likely to pass on infections, breeds rapidly, and is not endangered; moreover, millions of them are eaten every year. Although drawing ethical conclusions is difficult, at this stage of knowledge and debate it seems acceptable to manipulate pigs genetically and to proceed to using their organs for xenotransplantation trials when infection control measures and the scientific base justify it. The question of informed consent is likely to be a vexing one. It might end up more of a binding legal contract than consent as we understand it now. Xenotransplantation is also unlikely to cost less than, or significantly alleviate the shortage of, cadaveric organs in the short term. The international dimension of the risk of infection is becoming obvious, but there has so far been no effort to convene an international forum to agree on universally acceptable guidelines. PMID- 9361516 TI - Circulatory and anatomic differences among experimental gastric tubes as esophageal replacement. AB - In this experimental study we measured microcirculatory and anatomic differences among a newly developed technique of gastroplasty--fundus rotation gastroplasty (FRG)--and conventional (CG) and reversed (RG) gastric tubes as substitutes for the thoracic and cervical esophagus. After transhiatal esophageal resection, 36 large white pigs were randomly assigned to have an FRG, CG, or RG. Tube length, gastric volume, and compliance as well as blood flow in the tube and the remaining gastric reservoir (by laser Doppler flowmetry) were measured. The FRG tubes were 35.9 +/- 3.1 cm long, RG 38.7 +/- 3.3 cm, and CG 27.3 +/- 2.1 cm (p < 0.05). Gastric compliance was 20.8 ml in the FRG and 3.2 ml and 2.9 ml in the CG and RG, respectively (p < 0.001). Blood flow was significantly higher in FRG tubes than in RG tubes or CG tubes, resulting in a lower anastomotic failure rate (2/12 FRG, 6/12 CG, 7/12 RG). Hence a rotation flap of the gastric fundus (FRG) yields a long, well perfused tube by maintaining the blood supply of the gastric lesser curvature. FRG appears to be a good alternative to CG or RG as a substitute for the thoracic and cervical esophagus. PMID- 9361515 TI - Benign liver tumors: differential diagnosis and indications for surgery. AB - The differential diagnosis for hemangioma, focal nodular hyperplasia (FNH), and hepatocellular adenoma may be difficult. Reliable diagnosis is mandatory for the decision of whether to apply surgery or observation. Experience with long-term observation in nonoperated patients with hemangioma and FNH is limited. A group of 437 patients from a single institution were analyzed with regard to a diagnostic algorithm, the indications for surgery, and observation. There were 238 hemangiomas, 150 cases of FNH, 44 adenomas, and 5 mixed tumors. Of the 437 patients, 173 underwent surgery; 103 with hemangioma and 54 with FNH were observed at our own institution, whereas 117 patients underwent follow-up elsewhere or were lost. Among the operated patients with confirmed histology, a good diagnostic yield was found for a combination of ultrasonography (US), contrast (bolus)-enhanced computed tomography (CT), and labeled red blood cell (RBC) scanning: sensitivity 85.7%, specificity 100%, positive predictive value (PPV) 100%, negative predictive value (NPV) 81.8%, and accuracy 91.3%. For FNH and combination of US and CT plus cholescintigraphy showed a sensitivity 82.1%, specificity 97.1%, PPV 95.8%, NPV 84.6%, and accuracy 90.3%. Surgical mortality was 0.6%. Observation of patients with hemangioma and FNH for a median of 32 months revealed no increase in tumor size in 80% and a decrease in fewer than 7%. There was no tumor rupture and no evidence of malignant transformation. We concluded that liver hemangioma and FNH can be differentiated from adenoma with high sensitivity, specificity, and accuracy by labeled RBC scanning and cholescintigraphy in combination with US and contrast-enhanced CT. In the case of symptoms or an equivocal diagnosis with respect to adenoma or hepatocellular carcinoma, surgery can be performed with very low risk. Because in asymptomatic patients with observed hemangioma or FNH no increase of tumor size can be expected for many years, the indications for surgery must be carefully evaluated. PMID- 9361517 TI - Impact on outcome of additional microvascular anastomosis--supercharge--on colon interposition for esophageal replacement: comparative and multivariate analysis. AB - The impact on the outcome of an additional microvascular anastomosis--supercharge -on colon interposition for esophageal replacement was retrospectively evaluated by comparing it with colon interposition without supercharge. A series of 53 patients had undergone colon interposition for esophageal replacement at Kurume University Hospital from 1981 to 1996. The postoperative courses and the morbidity and mortality rates were compared between the 24 patients who underwent colon interposition without supercharge from 1981 to 1988 and the other 29 patients who underwent colon interposition with supercharge from 1989 to 1996. Risk factors for leakage of the esophagocolostomy and for hospital mortality after colon interposition were evaluated by multivariate analysis. Colon interposition with supercharge required a longer operation time but resulted in a lower incidence of necrosis in the colon graft and leakage in the esophagocolostomy (Odds ratio = 34), a shorter duration until peroral intake, and a shorter hospital stay compared to colonic interposition without supercharge. The addition of supercharge to colon interposition for esophageal replacement has been an effective option that has prevented serious complications caused by graft ischemia. PMID- 9361518 TI - Synthesis and biological investigations of pyrimidine derivatives. AB - The study concerns new syntheses of 5-hydroxy ether and 5-aminohydroxy ether derivatives of pyrimidine. When tested for antibacterial activity, some of the compounds exhibited promising effects. PMID- 9361519 TI - Chemical and biological properties of 5-indolones. AB - Indolones of the general formula 1 (Fig. 1 and 2) can act as Michael substrates, which readily add various nucleophiles. 1,4-Addition of S-nucleophiles to these indolones gives access to compounds of the general formula 2 (Fig. 2). The addition is reversible, meaning that these compounds behave as prodrugs of the (in-vitro) cytotoxic indolones. The addition products possess less cytotoxicity of their own, but can presumably release the parent indolones in-vivo. This behaviour makes them valuable compounds, allowing their use as cytotoxic agents. Furthermore, some of the addition products possess antibiotic activity, making them worth testing as agents against certain microbes. Their specificity towards certain microorganisms, which does not fit the usual scheme of activity towards gram positive or gram negative bacteria, is remarkable and needs further verification. PMID- 9361521 TI - Synthesis and antimicrobial activity of new 1-benzylbenzimidazolium chlorides. AB - 1-Benzylbenzimidazole reacts with chloromethylalkyl ethers or sulfides or chloromethylcycloalkyl ethers to produce 3-alkoxymethyl-1-benzylbenzimidazolium or 3-alkylthiomethyl-1-benzylbenzimidazolium or 1-benzyl-3 cycloalkoxymethylbenzimidazolium chlorides in very good yields. All the 1 benzylbenimidazolium chlorides showed antimicrobial activity. The relationship between chemical structure and antimicrobial activity was analyzed by quantitative structure-activity relationships (QSAR). PMID- 9361520 TI - Organic nitrates. II. Synthesis and biological activities of 4 nitrooxymethylphenyl-1,4-dihydropyridines. AB - Both 2-nitrooxymethyl-4-phenyl- (2) and 4-nitrooxymethylphenyl-1,4 dihydropyridines (3) represent new combinations of two different vasodilating structures. 2 could not be isolated due to its spontaneous lactonization. Derivatives of 3 were obtained via Hantzsch synthesis using nitrooxymethylated benzaldehydes. The inotropic potency in isolated porcine trabecular muscles and the vasodilator activity in isolated porcine coronary arteries of four nitrooxyphenyl-dihydropyridines were determined. Nitrendipine (NTD) and glyceryl trinitrate (GTN) were used for reference. 3 were negative inotropic, however, less than NTD and--except for the dicyano derivative 3d--more than GTN. Vasodilator properties were less pronounced than that of both nitrendipine and GTN. Vascular selectivity was low. PMID- 9361522 TI - Synthesis and antiviral activity of 5-ethyl-5-halo-6-alkoxy-(or azido)-5,6 dihydro-2'-deoxyuridine diastereomers as potential prodrugs to 5-ethyl-2' deoxyuridine. AB - A group of 5-ethyl-5-halo-6-alkoxy (or azido)-5,6-dihydro-2'-deoxyuridines, which differ in configuration at the C-5 and C-6 positions, were synthesized by the regiospecific addition of XR (X = I, Br, Cl; R = alkoxyl, azido) to the 5,6 olefinic bond of 5-ethyl-2'-deoxyuridine (EDU). In vitro antiviral (HSV-1, HSV-2, HCMV, VZV) activities were determined. Structure-activity studies showed that the C-5 halogeno (I, Br, Cl) and C-6 alkoxy (OMe, OEt) or azido, substituents were determinants of antiviral activity where the (5R,6R)-5 and (5S,6S)-6 diastereomers of 5-ethyl-5-iodo-6-methoxy-5,6-dihydro-2'-deoxyuridine exhibited greater potency against HSV-1, HSV-2, and HCMV than the related 5-chloro-6-ethoxy and 5-bromo (or chloro)-6-azido diastereomers. The most potent antiviral agents, (+)-trans-(5R,6R)-5 and (-)-trans-(5S,6S)-6 diastereomers of 5-ethyl-5-iodo-6 methoxy-5,6-dihydro-2'-deoxyuridine were approximately 2-to-8 fold more potent than the reference drug EDU against HSV-1 and HSV-2. PMID- 9361523 TI - Novel carbocyclic nucleosides containing a cyclopentyl ring. Adenosine and uridine analogues. AB - cis-3-Aminomethylcyclopentylmethanol (4) was used as a precursor in the synthesis of carbocyclic nucleosides containing adenine, hypoxanthine, 8-azahypoxanthine, uracil, and 5-iodouracil bases. None of these compounds had appreciable activity against eighteen viruses in the concentration ranges tested. Two of them showed a weak cytostatic activity against three tumor lines. PMID- 9361524 TI - Synthesis and antibacterial activities of new 1 beta-methylcarbapenems having a 1,3-diazabicyclo[3.3.0]octan-2,4-dione moiety. AB - The synthesis of a new series of 1 beta-methylcarbapenems having a 1,3 diazabicyclo[3.3.0]octane-2,4-dione moiety is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bateria are determined and the effect of substituent on the bicyclic ring as well as stereoisomerism was investigated. PMID- 9361525 TI - The features of Tenon's capsule at the limbus. AB - Glaucomatous optic neuropathy is a multifactorial disease, whose most important risk is high intraocular pressure. Filtering surgery, i.e. trabeculectomy, is the operation of choice to lower pressure, allowing the aqueous to outflow from the anterior chamber under the conjuctiva and Tenon's capsule. Failure to establish a filtration bleb is due in most cases to subconjunctival fibrosis, leading to bleb encapsulation (Tenon's cyst). Our study aimed to locate the best cleavage plane for aqueous drainage. Based on histological data, the subtenonian space appears to satisfy this requirement, due to low scarring aptitude and low resistance. PMID- 9361526 TI - The neural marker neuron-specific enolase in the development of embryo chicken retina: a morphological description. AB - The localisation and distribution of Neuron-specific enolase is reported in the avian Gallus domesticus retinal development by using immunocytochemistry. Neuron specific enolase was found to be present from the early days of incubation to the post-hatch period. The results obtained using this neural marker showed the development pattern of the distribution and the sequence of differentiation of the retinal neural structures. Like the finding of the members of the phylogenetic scale, this enzyme should prove to be a useful tool in the neural development of the chicken retina. PMID- 9361527 TI - Characterization and localization of epidermal growth factor receptors in human developing tooth. AB - In this study the characterization and localization of Epidermal Growth Factor (EGF) receptor in human jaws, from fetuses ranging in age from 9 to 12 weeks is reported for the first time. Binding of [125I]-EGF to membranes obtained from three separate pools of fetal jaws was specific and time- and temperature dependent. Analysis of the binding data revealed the presence of a single class of binding site with high affinity (Kd, 9.2 x 10(-10) mol/L) and mean binding capacity of 128 fmoles/mg protein. Immunohistochemical study demonstrated the presence of EGF receptors in the early developmental stages of human tooth. In the bud stage, the positivity was localized in the epithelial cells. In the cap stage, EGF receptors was present in the outer and inner enamel cells, in some cells of the stellate reticulum and in the mesenchymal papilla and follicle cells. In the bell stage, positivity for EGF receptors was present in the outer enamel epithelium, in some cells of the stellate reticulum and in the mesenchymal cells of the follicle and papilla. The presence of EGF receptors in the proliferative stages in both epithelial and mesenchymal cells suggests that EGF is involved in the early developmental stages of the human tooth germ. PMID- 9361528 TI - Morphometric analysis of the sacroiliac joint. AB - The sacroiliac (SI) joint is the point of articulation between the sacrum and the innominate bone of the pelvis. The anterior portion is synovial, and the posterosuperior portion is a typical syndesmosis. The SI joint may be affected by inflammatory or degenerative changes which include narrowing, minor sclerosis and erosion. Alterations in the anatomy of this joint may be involved in causing lower back pain. Radiodiagnosis of the width of the articular space is one of the tools utilized to evaluate the normal state of any joint. Scanty data is available on the morphometric characteristics of the SI joint. Therefore, the articular width space of the SI joint was measured to define its normal size in relation to age and sex. The study included 198 x-rays of the abdomen, in anteroposterior projection, of 112 males and 86 females (age range: 17 to 91 yrs). Individual films were divided into four classes according to age (< 50; 50 59; 60-69; > 70). The articular space of the SI joint is made up of a lateral and a medial part: the first representing the anterior articular space; the latter the posterior one. The anterior articular space of both the right and left joint, which was more easily visible and measurable was measured at the medium and inferior levels. Measurements were taken from the radiograms using a semiautomatic computerized system (Videoplan II, Image Analysis system-Kontron). The mean value of the articular space width a the medium and inferior levels, according to age group, was measured in both the males and females. The values obtained were studied using variance analysis. No significant differences were found in the mean values of the articular space width at the SI joint, when males and females were compared in relation to age. Moreover, the articular space width diminished with increasing the age. This fact was not always statistically significant. PMID- 9361529 TI - Constitutive and inducible nitric oxide synthases in mouse uterus and their changes following treatment with ovarian steroids. Immunocytochemical and histoenzymological studies. AB - Previous studies showed that different nitric oxide synthase isoforms are present in the uterus of laboratory mammals and that their expression is influenced by ovarian steroids. However, the results of these studies are not univocal, probably owing to the different hormonal treatments and techniques applied to reveal nitric oxide synthases. In this study we investigated the distribution and expression of constitutive and inducible nitric oxide synthase isoforms by immunocytochemistry and their changes following treatment of the mice with 17 beta-estradiol alone or in combination with medroxyprogesterone. Moreover, we compared the immunoreactivities for nitric oxide synthases with the histochemical reaction for NADPH-diaphorase, an enzyme that may be associated with nitric oxide synthase. The results obtained show that the two nitric oxide synthase isoforms are differently expressed in surface epithelium, glands, stromal cells and myometrium and that, as compared with the uteri from mice treated with estrogen alone, those from mice treated with estrogen plus progestin showed enhanced expression of constitutive nitric oxide synthase in the myometrium and of the inducible isoform in surface epithelium, glands, stromal cells and myometrium. The results obtained with NADPH-diaphorase reaction show that there is not a colocalization of nitric oxide synthase isoforms and NADPH-diaphorase, apart from a partial colocalization in part of the stromal cell population and myometrium. This provides evidence that NADPH-diaphorase histochemistry is not a valid technique to localize the sites of nitric oxide synthesis in the mouse uterus and that the use of this technique may generate misleading in the interpretation of the effect of ovarian steroids in regulating nitric oxide production by the different components of the uterine wall. PMID- 9361531 TI - The oesophageal Doppler monitor. PMID- 9361530 TI - Development of mouse submandibular gland studied by field emission scanning electron microscopy. AB - The ultrastructural organization of mouse submandibular gland from 15 days gestation to 180 days of age was studied by field emission scanning electron microscopy. At 15 days of gestation several groups of acini, intercalated and striated ducts were present. They consisted of numerous pyramidal and/or polyhedral cells with spherical or elongated nuclei and short microvilli. At 3 days after birth different shapes of acinar structures covered by a network of fine collagen bundles were observed. The acinar portions corresponded to the terminal tubules and showed the acinar cells containing immature secretory granules. Fractured specimens of ducts revealed a flat surface with large central nuclei. At 14 days after birth acinar terminal portions possessed a round shape; branches of either intercalated and striated ducts were also observed. Gap junctions and interdigitations were numerous at the base of acinar cells. At 30 days after birth the acinar terminal portions and striated ducts revealed a large number of secretory granules. Acinar cells showed a pyramidal shape and basal nuclei. Freeze-cracked surfaces of the striated ductal cells evidenced also a pyramidal shape. Secretory granules ranged from 0.3 to 1.2 microns in size and were clearly observed by infoldings of the basement membranes. At 90 days after birth the ultrastructural features were more differentiated when compared with the previous ages. The freeze-cracked specimens showed very numerous secretory granules in all acinar and striated ductal cells. The granules occupied almost all the apical region of the cells. The outer surface of the basement membrane of acinar and myoepithelial cells was constituted by a spongy-like material covered by fine collagen fibrils. At 180 days after birth numerous secretory granules were seen either in acinar and ductal cells. A morphofunctional polarization of the cell was finally clearly observed in that the cytoplasmic organelles were concentrated in the basal portion whereas the secretory granules were located in the apical region of the cells. PMID- 9361532 TI - Attention deficit hyperactivity disorder. PMID- 9361534 TI - An inspectorate for the health service? PMID- 9361533 TI - France seeks to curb health costs by fining doctors. PMID- 9361535 TI - Every system is designed to get the results it gets. PMID- 9361536 TI - Guidelines warn psychiatrists about memory recovery techniques. PMID- 9361537 TI - HIV treatment in children brought into line with that in adults. PMID- 9361538 TI - New renal scarring in children who at age 3 and 4 years had had normal scans with dimercaptosuccinic acid: follow up study. AB - OBJECTIVE: To determine up to what age children remain at risk of developing a new renal scar from a urinary tract infection. DESIGN: Follow up study. Families of children who had normal ultrasound scans and scanning with dimercaptosuccinic acid (DMSA) after referral with a urinary tract infection when aged 3 (209) or 4 (220) were invited to bring the children for repeat scans 2-11 years later. A history of infections since the original scan was obtained for children not having a repeat scan. SETTING: Teaching hospital. SUBJECTS: Children from three health districts in whom a normal scan had been obtained at age 3-4 years in 1985 1992 because of a urinary tract infection. MAIN OUTCOME MEASURE: Frequency of new renal scars in each age group. RESULTS: In each group, about 97% of children either had repeat scanning (over 80%) or were confidently believed by their general practitioner or parent not to have had another urinary infection. The rate of further infections since the original scan was similar in the 3 and 4 year old groups (48/176 (27%)) and 55/179 (31%)). Few children in either group known to have had further urinary infections did not have repeat scanning (3/209 (1.4%) and 4/220 (1.8%)). In the 3 year old group, 2.4% (5/209) had one or more new kidney scars at repeat scanning (one sided 95% confidence interval up to 5.0%), whereas none of the 4 year olds did (one sided 95% confidence interval up to 1.4%). The children who developed scars were all aged under 3.4 years when scanned originally. CONCLUSIONS: Children with a urinary tract infection but unscarred kidneys after the third birthday have about a 1 in 40 risk of developing a scar subsequently, but after the fourth birthday the risk is either very low or zero. Thus the need for urinary surveillance is much reduced in a large number of children. PMID- 9361539 TI - Intraoperative intravascular volume optimisation and length of hospital stay after repair of proximal femoral fracture: randomised controlled trial. AB - OBJECTIVES: To assess whether intraoperative intravascular volume optimisation improves outcome and shortens hospital stay after repair of proximal femoral fracture. DESIGN: Prospective, randomised controlled trial comparing conventional intraoperative fluid management with repeated colloid fluid challenges monitored by oesophageal Doppler ultrasonography to maintain maximal stroke volume throughout the operative period. SETTING: Teaching hospital, London. SUBJECTS: 40 patients undergoing repair of proximal femoral fracture under general anaesthesia. INTERVENTIONS: Patients were randomly assigned to receive either conventional intraoperative fluid management (control patients) or additional repeated colloid fluid challenges with oesophageal Doppler ultrasonography used to maintain maximal stroke volume throughout the operative period (protocol patients). MAIN OUTCOME MEASURES: Time declared medically fit for hospital discharge, duration of hospital stay (in acute bed; in acute plus long stay bed), mortality, perioperative haemodynamic changes. RESULTS: Intraoperative intravascular fluid loading produced significantly greater changes in stroke volume (median 15 ml (95% confidence interval 10 to 21 ml)) and cardiac output (1.2 l/min (0.1 to 2.3 l/min)) than in the conventionally managed group (-5 ml ( 10 to 1 ml) and -0.4 l/min (-1.0 to 0.2 l/min)) (P < 0.001 and P < 0.05, respectively). One protocol patient and two control patients died in hospital. In the survivors, postoperative recovery was significantly faster in the protocol patients, with shorter times to being declared medically fit for discharge (median 10 (9 to 15) days v 15 (11 to 40) days, P < 0.05) and a 39% reduction in hospital stay (12 (8 to 13) days v 20 (10 to 61) days, P < 0.05). CONCLUSIONS: Proximal femoral fracture repair constitutes surgery in a high risk population. Intraoperative intravascular volume loading to optimal stroke volume resulted in a more rapid postoperative recovery and a significantly reduced hospital stay. PMID- 9361540 TI - Effects of obesity and weight loss on left ventricular mass and relative wall thickness: survey and intervention study. AB - OBJECTIVES: To investigate the consequences of longstanding obesity on left ventricular mass and structure and to examine the effects of weight loss on these variables. DESIGN: Cross sectional survey and controlled intervention study. SETTING: City of Gothenburg and surrounding areas. Sweden. SUBJECTS: 41 obese patients treated with weight reducing gastric surgery, 31 obese patients treated conventionally, and 43 non-obese subjects. MAIN OUTCOME MEASURES: Changes in left ventricular mass and relative wall thickness. RESULTS: Obese patients had higher blood pressure, greater left ventricular mass, and increased relative wall thickness than did matched non-obese control subjects. Obese subjects treated with gastric surgery had a substantial weight loss and a significant reduction in all variables when compared with conventionally treated obese subjects. Univariate and multivariate analysis of pooled data from the two groups of obese subjects showed that changes in relative wall thickness and left ventricular mass were more closely related to the change in weight than to the concomitant change in blood pressure. CONCLUSIONS: Structural heart abnormalities occurring in conjunction with obesity diminish after weight loss. The regression in these structural aberrations is better predicted by the weight loss than by the accompanying reduction in blood pressure. To prevent or improve abnormalities of heart structure in obese people, weight control should be the primary goal; it should be regarded as at least as important as regulating blood pressure. PMID- 9361541 TI - Impact of medical school teaching on preregistration house officers' confidence in assessing and managing common psychological morbidity: three centre study. PMID- 9361542 TI - Occurrence of renal scars in children after their first referral for urinary tract infection. PMID- 9361543 TI - Can students learn clinical method in general practice? A randomised crossover trial based on objective structured clinical examinations. AB - OBJECTIVE: To determine whether students acquired clinical skills as well in general practice as in hospital and whether there was any difference in the acquisition of specific skills in the two environments. DESIGN: Randomised crossover trial. SUBJECTS AND SETTING: Annual intake of first year clinical students at one medical school. INTERVENTION: A 10 week block of general internal medicine, one half taught in general practice, the other in hospital. Students started at random in one location and crossed over after five weeks. OUTCOME MEASURES: Students' performance in two equivalent nine station objective structured clinical examinations administered at the mid and end points of the block: a direct comparison of the two groups' performance at five weeks; analysis of covariance, using their first examination scores as a covariate, to determine students' relative improvement over the second five weeks of their attachment. RESULTS: 225 students rotated through the block; all took at least one examination and 208 (92%) took both. For the first half of the year there was no significant difference in the students' acquisition of clinical skills in the two environments; later, however, students taught in general practice improved slightly more than those taught in hospital (P = 0.007). CONCLUSIONS: Students can learn clinical skills as well in general practice as in hospital; more work is needed to clarify where specific skills, knowledge, and attitudes are best learnt to allow rational planning of the undergraduate curriculum. PMID- 9361544 TI - Epilepsy in childhood. PMID- 9361545 TI - ABC of palliative care. Breathlessness, cough, and other respiratory problems. PMID- 9361546 TI - Why is Sweden rethinking its NHS style reforms? PMID- 9361547 TI - Risk language and dialects. PMID- 9361548 TI - An attempt to save money by using mandatory practice guidelines in France. PMID- 9361550 TI - Graded exercise in chronic fatigue syndrome. Including patients who rated themselves as a little better would have altered results. PMID- 9361549 TI - Graded exercise in chronic fatigue syndrome. Patients should have initial period of rest before gradual increase in activity. PMID- 9361551 TI - Graded exercise in chronic fatigue syndrome. Patients were selected group. PMID- 9361552 TI - Graded exercise in chronic fatigue syndrome. Chronic fatigue syndrome is heterogeneous condition. PMID- 9361553 TI - Chronic fatigue syndrome in children. Journal was wrong to critizise study in schoolchildren. PMID- 9361554 TI - Chronic fatigue syndrome in children. Patient organisations are denied a voice. PMID- 9361555 TI - Chronic fatigue syndrome in children. All studies must be subjected to rigorous scrutiny. PMID- 9361556 TI - Special hospitals. Special hospitals are not prisons... PMID- 9361557 TI - Special hospitals ... but have a history of problems. PMID- 9361558 TI - Summative assessment compounds workload for MRCGP examination. PMID- 9361559 TI - Inequality in funding for AIDS across England threatens regional services. PMID- 9361560 TI - New combined hepatitis A and B vaccine. PMID- 9361561 TI - Requesting necropsies. Health care must be both evidence based and humanity based. PMID- 9361562 TI - Requesting necropsies. General practitioners should be taught relevant skills during vocational training. PMID- 9361563 TI - Requesting necropsies. Necropsy rate was increased to 21% in one hospital. PMID- 9361564 TI - The future of healthcare systems. Many questions about reform of health sector remain unanswered. PMID- 9361565 TI - The future of healthcare systems. Rigid managed care programmes should never replace systems that allow flexibility. PMID- 9361566 TI - The future of healthcare systems. Method for rigorously assessing cost effectiveness of new drugs must be set up. PMID- 9361567 TI - Deaths from cervical cancer began falling before screening programmes were established. PMID- 9361568 TI - Love, boundaries, and the patient-physician relationship. AB - Physicians often use their relationships with patients to promote specific therapeutic goals. Because of their personal histories, values, and biases, patients may react to physicians in ways that inhibit or enhance the relationship. The feelings that are aroused may induce physicians to become overly distant, engendering patient and physician dissatisfaction, or to become overly involved emotionally, which can have serious psychological and clinical consequences. We explore how a balance between clinical objectivity and bonding with the patient is optimal and achievable. The nature and origin of personal boundaries are described. Boundary transgressions on the part of the patient are discussed, and the means of preventing transgressions by both patients and physicians through medical education, the process of self-awareness, and an exploration of family-of-origin issues are proposed. Through attention to communication with patients, the physician can maintain an empathetic yet objective relationship with the patient. PMID- 9361569 TI - Case of the month. Autopsy Committee of the College of American Pathologists. PMID- 9361570 TI - Homocyst(e)ine and coronary artery disease. Clinical evidence and genetic and metabolic background. AB - Many studies have demonstrated a strong association between elevated plasma total homocyst(e)ine levels and vascular diseases. Consequently, hyperhomocyst(e)inemia is now generally accepted as an independent risk factor for coronary artery disease. We critically reviewed the results of 35 human studies in which the levels of plasma total homocysteine were measured in patients with atherosclerotic diseases (n = 4338) and in controls (n = 22,593). Total homocysteine levels were consistently higher in patients than in controls. The average of this increment among 23 case-control studies was 26%. New insights into the biochemical pathways of total homocysteine metabolism, the factors that influence total homocysteine levels, genetic contributions to hyperhomocyst(e)inemia, the pathogenesis of homocyst(e)ine-induced vascular damage, and current recommendations for treatment of hyperhomocyst(e)inemia were also reviewed. Various lines of evidence now link hyperhomocyst(e)inemia with vascular diseases. Although there are no data from double-blind, placebo controlled clinical trials of treatment for hyperhomocyst(e)inemia, the strong epidemiologic and experimental evidence argues for treatment of hyperhomocyst(e)inemia; in fact, its treatment with low doses of vitamins is thought to be safe and is inexpensive. PMID- 9361571 TI - Cost-effectiveness of noninvasive diagnostic aids in suspected pulmonary embolism. AB - BACKGROUND: Noninvasive instruments such as plasma D-dimer measurement (DD) and lower-limb compression ultrasonography (US) are being increasingly advocated to reduce the number of necessary angiograms in patients having suspected pulmonary embolism (PE) and a nondiagnostic lung scan. We therefore designed a decision analysis model (1) to evaluate the cost-effectiveness of combining these noninvasive diagnostic aids with lung scan and angiography in the diagnosis of PE and (2) to determine the optimal sequence and combination of tests taking into account the clinical probability of PE. METHODS: We performed a cost effectiveness analysis based on literature data, including data from a management study in our institution. Six diagnostic strategies were compared with the reference, ie, lung scan followed when nondiagnostic (low or intermediate probability) by angiography. In all strategies, PE was ruled out by a normal or near-normal scan, a negative DD (plasma level below 500 micrograms/L), or a negative angiogram. Pulmonary embolism was diagnosed and anticoagulant treatment was undertaken in the presence of a high-probability lung scan, deep vein thrombosis showed by US, or a positive angiogram. In case of a nondiagnostic scan (low or intermediate probability), patients could be either treated or not treated, or undergo other tests, according to the selected strategy. RESULTS: Under baseline conditions (prevalence of PE, 35%), strategies combining DD and US with lung scan, angiography being done only in case of an inconclusive noninvasive workup (DD level > 500 micrograms/L, normal US, and nondiagnostic lung scan), were most cost-effective. This approach yielded a 9% incremental cost reduction and a 37% to 47% decrease in the number of necessary angiograms compared with the reference strategy (scan +/- angiography). For patients with a low clinical probability of PE (< or = 20%), withholding treatment from those with a low-probability lung scan without performing an angiogram proved safe and highly cost-effective (30% cost reduction), provided US showed no deep vein thrombosis. CONCLUSION: The DD test and US are cost-effective in the diagnostic workup of PE, whether performed after or before lung scan, thus allowing centers devoid of lung scanning and/or angiography facilities to screen patients with suspected PE and avoid costly referrals. In patients with a low clinical probability, a low-probability lung scan, and a normal US, treatment may be withheld without resorting to angiography. PMID- 9361572 TI - The importance of initial heparin treatment on long-term clinical outcomes of antithrombotic therapy. The emerging theme of delayed recurrence. AB - BACKGROUND: Recent clinical trials of venous thromboembolism treatment suggest inadequate initial heparin therapy predisposes patients to late recurrence of thromboembolism. However, a recent review article was unable to demonstrate a relationship between initial heparin therapy and late recurrence. OBJECTIVE: To evaluate the relationship between initial heparin treatment and long-term clinical outcome in 3 consecutive, randomized, double-blind trials that used similar study designs and patient populations and objective documentation of recurrent venous thromboembolism. METHODS: The trials were performed sequentially and compared the use of continuous intravenous with subcutaneous heparin, continuous intravenous heparin for 10 or 5 days, and continuous intravenous heparin with once-daily subcutaneous low-molecular-weight heparin. All patients were followed up for 3 months to assess the a priori hypothesis that inadequate initial heparin therapy could lead to recurrent venous thromboembolism during long-term therapy with warfarin sodium. RESULTS: The following were the observed rates of recurrent venous thromboembolism: continuous intravenous heparin, 3 (5.2%) of 58 patients vs subcutaneous heparin, 11 (19.3%) of 57 patients; continuous intravenous heparin for 10 days, 7 (7.0%) of 100 patients or for 5 days, 7 (7.1%) of 99 patients; and continuous intravenous heparin, 15 (6.9%) of 219 patients vs low-molecular-weight heparin, 6 (2.8%) of 213 patients. Pooled analysis of the patients treated with continuous intravenous heparin showed that of the total 32 patients with recurrent venous thromboembolism, in 6 patients thromboembolism occurred early (< 10 days) and 26 patients thromboembolism occurred late. Of these patients, the majority (20/32 [62.5%]) had therapeutic prothrombin time or international normalized ratio values before or at the time of the recurrent thromboembolic event. CONCLUSION: Our findings demonstrate that the initial heparin treatment affects the long-term outcome. This conclusion applies when these data are analyzed for each individual study by treatment group, observed difference in outcome, and pooled analysis. PMID- 9361573 TI - Trends in cholesterol knowledge and screening and hypercholesterolemia awareness and treatment, 1980-1992. The Minnesota Heart Survey. AB - BACKGROUND: National cholesterol education initiatives were implemented in the middle to late 1980s. This study examines whether there were significant increases in population cholesterol knowledge and screening and hypercholesterolemia awareness and treatment from 1980 to 1992. METHODS: Three population-based surveys were conducted among adults aged 25 to 74 years in 1980 1982 (N = 4086), 1985-1987 (N = 5735) and 1990-1992 (N = 6305) in the Minneapolis St Paul, Minn, metropolitan area as part of the Minnesota Heart Survey. Personal interviews about knowledge of cholesterol level and hypercholesterolemia awareness and treatment were conducted. Total serum cholesterol was measured; hypercholesterolemia was defined as having a total cholesterol level of 6.21 mmol/L or more (> or = 240 mg/dL) or current use of cholesterol-lowering medications. Hypercholesterolemia awareness was defined as the belief of a participant with hypercholesterolemia that her or his total cholesterol was high. RESULTS: Knowledge increased from 15% in 1980-1982 to 17% in 1985-1987 to 55% in 1990-1992 (P < .001) in women; similar trends were observed for men (19%, 22%, and 47%, respectively; P < .001). Hypercholesterolemia awareness doubled during the decade (women: 17%, 1980-1982; 24%, 1985-1987; 60%, 1990-1992; P < .001; men: 25%, 30%, and 55%, respectively; P < .001). Among participants who reported physician-diagnosed hypercholesterolemia, the prevalence of current pharmacological treatment increased from 9% in 1980-1982 to 14% in 1990-1992 in women, and from 7% to 13%, respectively, in men. CONCLUSIONS: Cholesterol knowledge and hypercholesterolemia awareness and treatment increased substantially during the 1980s, concurrent with educational initiatives of the National Cholesterol Education Program and other efforts. PMID- 9361574 TI - Provider training for patient-centered alcohol counseling in a primary care setting. AB - OBJECTIVE: To assess the impact of a brief training program on primary care providers' skills, attitudes, and knowledge regarding high-risk and problem drinking. DESIGN: Training plus pretesting and posttesting for program efficacy. SETTING: Ambulatory primary care clinic; academic medical center. PARTICIPANTS: Fourteen attending physicians, 12 residents, and 5 nurse practitioners were randomized by clinical team affiliation to a Special Intervention or usual care condition of a larger study. We report the results of the training program for the Special Intervention providers. INTERVENTION: Providers received a 2-hour group training session plus a 10- to 20-minute individual tutorial session 2 to 6 weeks after the group session. The training focused on teaching providers how to perform patient-centered counseling for high-risk and problem drinkers. MAIN OUTCOME MEASURES: Alcohol counseling skills; attitudes regarding preparedness to intervene and perceived importance and usefulness of intervening with high-risk and problem drinkers; and knowledge of the nature, prevalence, and appropriate treatment of alcohol abuse in primary care populations. RESULTS: After training, providers scored significantly higher on measures of counseling skills, preparedness to intervene, perceived usefulness and importance of intervening, and knowledge. CONCLUSION: A group training program plus brief individual feedback can significantly improve primary care providers' counseling skills, attitudes, and knowledge regarding high-risk and problem drinkers. PMID- 9361575 TI - Enhancing mammography use in the inner city. A randomized trial of intensive case management. AB - BACKGROUND: Breast cancer screening with mammography is an effective intervention for women aged 50 to 75 years but it is underused, especially by the urban poor. OBJECTIVE: To improve mammography completion rates for urban women aged 52 to 77 years who had not had a mammogram in at least 2 years. METHODS: We conducted a randomized controlled trial of a case management intervention by culturally sensitive community health educators vs usual care in 6 primary care practices supported by a computerized clinical information system. RESULTS: Women in the intervention group were nearly 3 times as likely to receive a mammogram (relative risk, 2.87; 95% confidence interval, 1.75-4.73). The benefit persisted when analyzed by age; race, and prior screening behavior. This intervention was practice based, not dependent on visits, and enhanced the efficacy of an already successful computerized preventive care information system. CONCLUSIONS: Personalized education and case management are successful in enhancing compliance with breast cancer screening among historically noncompliant vulnerable urban women. This intervention, when combined with a preventive care information system, has the potential to achieve Healthy People 2000 objectives for breast cancer screening. PMID- 9361576 TI - Initial and steady-state effects of diphenhydramine and loratadine on sedation, cognition, mood, and psychomotor performance. AB - BACKGROUND: The classic, first-generation histamine1-receptor antagonists used to treat allergic disorders frequently cause sedation. In contrast, sedation is reduced or absent after administration of recommended doses of second-generation histamine1-receptor antagonists. We measured the initial and steady-state effects of diphenhydramine, a first-generation antihistamine, and loratadine, a second generation antihistamine, by means of a comprehensive battery of psychometric tests that mirror real-world tasks. METHODS: Healthy volunteers (N = 98) were randomly assigned in a double-blind fashion to receive loratadine (n = 33), diphenhydramine (n = 32), or placebo (n = 33). A computerized test battery was administered at baseline, on day 1 after administration of the initial dose, and on days 3 and 5. RESULTS: After the initial dose, subjects taking diphenhydramine demonstrated poorer cognitive performance than subjects taking loratadine or placebo on tasks of divided attention, working memory, speed, and vigilance. Subjects taking diphenhydramine also reported greater fatigue and sleepiness and lower levels of motivation, and rated the quality of their performance as lower than subjects taking loratadine or placebo. On day 3, subjects taking diphenhydramine continued to show more fatigue and lower motivation, and rated the quality of their test performance as poorer than subjects taking loratadine or placebo. There were no differences between loratadine and placebo after the initial dose or steady-state (day 5) dosing for any measure of cognitive or psychomotor test performance, mood, or sedation. CONCLUSIONS: Patients taking diphenhydramine may be at risk of lapses and significant errors that may lead to potential hazards and decreased work productivity. PMID- 9361577 TI - Mycobacteremia in patients with the acquired immunodeficiency syndrome. AB - BACKGROUND: Bacillemia is a key event in the pathogenesis of tuberculosis. Although current evidence indicates that Mycobacterium tuberculosis bacteremia is rare in patients seronegative for the human immunodeficiency virus, it has been increasingly reported in patients with the acquired immunodeficiency syndrome (AIDS). OBJECTIVE: To determine clinical and laboratory characteristics of patients with AIDS and tuberculosis with and without bacillemia. METHODS: Fifty patients with AIDS with clinical suspicion of disseminated mycobacterial disease were prospectively selected. Three consecutive blood samples were collected for culture using a standardized protocol. RESULTS: Mycobacterium was isolated from any body site in 42 patients (84%). Bacillemia was detected in 30 (71.4%) of these 42 patients: 11 (28.2%) caused by Mycobacterium avium-intracellulare complex and 19 (71.8%) caused by M tuberculosis. Blood culture was the only method used to confirm the diagnosis in 5 (15%) of the 33 tuberculosis cases. Tuberculosis in patients with AIDS developed with nonspecific insidious symptoms, a remarkable elevated alkaline phosphatase level, and without the classic miliary radiological pattern. We could demonstrate 2 previously unrevealed clinical characteristics of bacteremic tuberculosis in patients with AIDS: a shift to the left in the white blood cell count and abdominal lymph node enlargement. In patients with tuberculosis, the in-hospital mortality rate was higher among patients with bacillemia, although the posttreatment survival rate was comparable. CONCLUSIONS: Blood culture is a valuable tool to confirm the clinical diagnosis of disseminated tuberculosis in patients with AIDS and can distinguish patients with characteristic clinical findings and outcome. Abdominal ultrasonography may be an additional helpful tool to identify these patients. PMID- 9361578 TI - Prevalence of infection with dengue virus among international travelers. AB - BACKGROUND: Dengue has been recognized as a potential hazard to tourists. A prospective, controlled study in the outpatient clinic of a German infectious disease clinic was conducted to assess the prevalence of dengue virus infection among international travelers. METHODS: Serum samples from 130 patients with signs or recent history clinically compatible with dengue (fever, headache, muscle and joint pain, or rash), 95 matched controls with diarrhea, and 26 patients who never visited a country endemic for dengue were investigated. RESULTS: Nine (6.9%) of the 130 patients with compatible symptoms and 1 (1%) of the 95 controls with diarrhea developed rising antibody titers against dengue virus. Of these 10 patients with probable dengue infection, 6 had been to Thailand, 2 to Malaysia, and 1 each to Indonesia and Brazil. CONCLUSIONS: Infection with dengue virus appears to be a realistic threat to travelers to Southeast Asia. Symptoms commonly associated with dengue, such as fever, myalgia, arthralgia, and vomiting, can be helpful for diagnosis when present, but the absence of typical symptoms does not exclude infection. PMID- 9361579 TI - A meta-analysis of zinc salts lozenges and the common cold. AB - BACKGROUND: In the United States, the common cold has been estimated to cost more than $3.5 billion a year. Despite several randomized clinical trials, the effect of treating colds with zinc salts lozenges remains uncertain because of conflicting results. OBJECTIVE: To conduct a meta-analysis of published randomized clinical trials on the use of zinc salts lozenges in colds using a random effects model. RESULTS: Eight clinical trials of treating adults with zinc salts lozenges were identified. After excluding 2 studies that used nasal inoculation of rhinovirus, 6 trials were combined and analyzed. The summary odds ratio for the presence of any cold symptoms at 7 days was 0.50 (95% confidence interval, 0.19-1.29). CONCLUSION: Despite numerous randomized trials, the evidence for effectiveness of zinc salts lozenges in reducing the duration of common colds is still lacking. PMID- 9361580 TI - Late complications in remission from Cushing disease. Recurrence of tumor with reinfarction or transformation into a silent adenoma. AB - Two of 4 patients who underwent spontaneous remission from Cushing disease (CD) demonstrated regrowth of the pituitary adenoma 2 and 5 years later. In the first patient, the recurrent tumor also secreted corticotropin, with subsequent relapse of fulminant cushingoid features. However, after 14 more months, it again became infarcted, and the patient underwent complete clinical remission, which has persisted for about 3 years. In the second patient, the regrowth of the tumor occurred silently, as no clinical cushingoid features or rise in cortisol levels were noticed. Because of its size, the tumor was resected and found to have immunoreactivity for corticotropin (silent corticotroph adenoma). About 4 years after the first operation, a second surgical procedure was performed because of massive regrowth of the tumor. Again, there was no concomitant elevation of cortisol levels or endocrinologic symptoms. This time, the tumor did not even stain for corticotropin. While spontaneous remission in CD is rare, recurrence is even rarer. Reremission of CD and the change from a corticotropin-secreting adenoma to a silent one are described herein for the first time (to our knowledge). These cases demonstrate that patients with CD have to receive careful follow-up, even if they undergo remission, and that the long-term outcome of such remission is unpredictable. PMID- 9361581 TI - Atypical polymyalgia rheumatica as a presentation of metastatic cancer. PMID- 9361582 TI - Phentermine--resin or salt--there are differences. PMID- 9361583 TI - Endoscopic ultrasonography. PMID- 9361584 TI - Towards international consensus in peripheral arterial thrombolysis. PMID- 9361585 TI - Hereditary breast cancer. AB - BACKGROUND: Hereditary breast cancer is thought to account for less than 10 per cent of all breast cancers. Recently there have been significant advances in understanding of the genetics, with the sequencing of the genes BRCA1 and BRCA2 which are associated with hereditary breast cancer. METHODS AND RESULTS: Current understanding of hereditary breast cancer and its impact on the management of women with this disease is reviewed. CONCLUSION: Problems in accurate testing for breast cancer-associated genes remain. No reliable simple test exists because of the large number of mutations present in these genes. The implications of different mutations remain poorly understood. Guidelines for the management of carriers of the breast cancer-associated genes remain controversial. PMID- 9361586 TI - Bacterial translocation in multiple organ failure: cause or epiphenomenon still unproven. AB - BACKGROUND: A body of evidence exists for the occurrence of bacterial translocation and its relationship to multiple organ failure (MOF). METHODS: Relevant articles on bacterial translocation (the phenomenon defined as the passage of microbes and endotoxin across the intestinal barrier) in patients prone to develop MOF and in representative animal studies were selected. To interpret and evaluate the evidence for bacterial translocation in current literature, the endpoints generally used are discussed. RESULTS: Fractional data from individual manuscripts were tabulated and assessed for statistical significance with chi 2 analysis. Various clinically relevant stimuli, postulated as important causative factors for the development of MOF, appeared to be interrelated and related to bacterial translocation itself. CONCLUSIONS: Convincing evidence exists that bacterial translocation can occur in humans during various disease processes. However, it remains to be determined whether a causal relationship between bacterial translocation and MOF exists. MOF is probably multifactorial and not uniform in origin; when evaluating translocation as a causative factor in the absence of an infective focus, the type of initiating event and the period of time after which MOF develops should be taken into account. The origin of early MOF is probably a non-bacterial, extensive, inflammatory response resulting in massive generalized endothelial cell activation. Late MOF may be caused primarily by bacterial translocation inducing an imbalance between proinflammatory and anti-inflammatory cytokines. PMID- 9361587 TI - Ileoanal reservoir dysfunction: a problem-solving approach. AB - BACKGROUND: Many technical difficulties of the ileoanal reservoir operation have been overcome, allowing acceptable morbidity in the hands of both the frequent and less frequent operator. However, a minority of patients have persistently unsatisfactory pouch function, which can be a difficult problem to manage. METHODS: A Medline search was carried out to identify relevant papers published from November 1996 to January 1978. For clinical information more emphasis was given to recent publications with larger numbers. Where appropriate, information from other sources and some local data were included. RESULTS: Most patients empty the pouch four to eight times a day with perfect continence and no urgency, and are considered to have acceptable function with which they are satisfied. Patients who have poor function beyond an easily treated episode of pouchitis require the expertise of a multidisciplinary team offering some understanding of the anatomy, physiology and pathology of the gastrointestinal tract in general and of the ileal reservoir in particular. A thorough and persistent approach to difficult cases is often rewarded with a good outcome, with the exception of problems arising from postoperative sepsis. The temptation to use pouchitis as a waste-basket diagnosis for poorly understood dysfunction should be avoided. Problems causing poor function may originate in the pouch (including pelvic sepsis), the pouch outlet, or the small bowel above the pouch, and these areas need to be considered in each case. CONCLUSION: To optimize the benefits of restorative pouch surgery, both patients and physicians need to understand aspects of fine tuning of pouch function, including diet, medication and lifestyle. In managing ileoanal reservoir dysfunction the temptation to procrastinate should be resisted; an approach that is systematic and sympathetic should be adopted. PMID- 9361588 TI - Duplex assessment of run-off before femorocrural reconstruction. AB - BACKGROUND: This study was a prospective evaluation of colour duplex imaging for the assessment of distal run-off before femorocrural reconstruction. METHODS: Patients with critical ischaemia who required a distal bypass underwent preoperative run-off assessments using dependent Doppler, arteriography and duplex imaging by a vascular surgeon, radiologist and technologist respectively; each was blinded to the findings of the others. Preoperative data were compared with intraoperative clinical findings and completion flow studies/ arteriograms. RESULTS: Forty-three consecutive patients (33 men, ten women; mean age 78 (range 53-95) years; 12 diabetic) undergoing 44 femorocrural reconstructions for critical ischaemia were assessed. The 30-day primary cumulative graft patency for the series was 86 per cent. Dependent Doppler correctly predicted a suitable run off vessel in 21 limbs but was indeterminate in four and unrecordable in 19. Arteriography correctly predicted a suitable run-off vessel in 32 cases, but was indeterminate in six and failed to demonstrate run-off in three patients. Arteriography suggested an inferior vessel in three cases. Duplex correctly predicted a suitable run-off vessel for all 44 grafts. CONCLUSION: Duplex imaging is superior to arteriography for preoperative assessment of distal run-off for femorocrural reconstruction. PMID- 9361589 TI - Subfascial endoscopic perforator surgery is associated with significantly less morbidity and shorter hospital stay than open operation (Linton's procedure) AB - BACKGROUND: Subfascial endoscopic perforator surgery (SEPS) is the minimally invasive alternative to the open (Linton's) procedure. This new technique may allow perforating vein interruption with fewer complications and a shorter postoperative hospital stay. METHODS: This study was a case note review of 67 procedures: 30 SEPS and 37 Linton's. RESULTS: There were no significant differences between the two groups in age, sex and indication for surgery. SEPS was associated with a significantly reduced postoperative stay in hospital (median 2 (range 1-49) days) compared with the Linton's procedure (median 9 (range 3-36) days) (P < 0.01). Nine patients who had Linton's procedure suffered a calf wound complication compared with none who had SEPS. The presence of an open ulcer at the time of surgery did not prolong the duration of stay in either group, nor did it increase the incidence of calf wound complications. CONCLUSION: In patients undergoing calf perforator interruption for chronic venous insufficiency, SEPS is associated with significantly less morbidity and a shorter hospital stay than Linton's procedure. SEPS can be performed safely at the same time as skin grafting and in the presence of an open ulcer without any increase in wound complications. PMID- 9361590 TI - Prospective comparison of endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography in the detection of bile duct stones. AB - BACKGROUND: Conventional ultrasonography is used widely in the investigation of gallstone disease but is limited in the detection of bile duct stones due to poor visualization of the distal bile duct. Endoscopic retrograde cholangiopancreatography (ERCP) is currently the investigation of choice for suspected choledocholithiasis, but is not without morbidity. Endoscopic ultrasonography clearly visualizes the entire extrahepatic biliary tree and avoids the need for ERCP in many patients. METHODS: Some 50 patients with suspected duct stones underwent endoscopic ultrasonography followed by ERCP. All cholangiograms were performed or interpreted by a second doctor blinded to the results of endoscopic ultrasonography. RESULTS: Both tests were successful in 46 patients; both tests failed in two patients and ERCP alone failed in a further two. Duct stones were confirmed in 24 patients. Sensitivity (95 per cent confidence interval (c.i.)) of ERCP and endoscopic ultrasonography in identifying these stones was 79 (58-93) per cent and 88 (68-97) per cent respectively; specificity (95 per cent c.i.) was 92 (75-99) per cent and 96 (80-100) per cent. CONCLUSION: Endoscopic ultrasonography accurately identifies bile duct stones. It is recommended in all patients with a risk of duct stones but especially in those with a history of ERCP-induced pancreatitis, when other pathology is suspected, when ERCP has failed, when bile duct abnormalities are suspected during pregnancy and in patients with acute pancreatitis. PMID- 9361591 TI - Low mortality following resection for pancreatic and periampullary tumours in 1026 patients: UK survey of specialist pancreatic units. UK Pancreatic Cancer Group. AB - BACKGROUND: Recent studies have suggested that the mortality rate from pancreatic resection for cancer is high in the UK compared with that in published series. A survey of specialist units was conducted to determine whether the results differed from those in general units. METHODS: The postoperative outcome following resection of pancreatic and periampullary tumours was analysed from specialist units in the UK and compared with that of other multi-institutional and large single institutional studies published recently (1900-1996). RESULTS: A total of 1026 resections was reported from 21 units (33 surgeons). Postoperative complications necessitated reoperation in 57 patients (6 per cent) and there were 58 deaths (6 per cent) in hospital. Pylorus-preserving resections were performed in 102 (41 per cent) of 250 patients with ampullary adenocarcinoma undergoing a major right-sided resection and in 123 (32 per cent) of 381 patients with ductal adenocarcinoma of the head of the pancreas undergoing right-sided resection (chi 2 = 4.01, 1 d.f., 2P = 0.04). The mean number of resections for pancreatic ductal adenocarcinoma was 3.41 (range 1.0-7.1) per institution per year. Combining these data with those from the nine published series from specialist units, there was a lower mortality rate compared with the results of five published general surveys (median 4.9 per cent (95 per cent confidence interval (c.i.) 3.1-8.0 per cent) versus 9.8 (2.5-23.2 per cent), 2P < 0.01) and specialist units had a higher volume caseload (median 5.5 (95 per cent c.i. 4.2-8.1) versus 0.5 (-0.2-2.0) cases per institution per year, 2P < 0.001). Postoperative mortality was related to caseload both for the UK (chi 2 = 7.17, 1 d.f., P < 0.01) and for all the data combined (chi 2 = 40.4, 1 d.f., P < 0.0001). CONCLUSION: The results from specialist units in the UK compare favourably with those from specialist units outside the UK and are superior to those from non-specialist units. The mortality rate is generally lower in units with a higher caseload. PMID- 9361592 TI - Role of preoperative localization in the management of primary hyperparathyroidism. AB - BACKGROUND: The advantages of preoperative localization in the management of primary hyperparathyroidism have not been clearly demonstrated. The aim of this study was to investigate prospectively the accuracy of three localization techniques in patients with this condition. METHODS: Forty-nine consecutive patients with primary hyperparathyroidism underwent ultrasonography, magnetic resonance imaging (MRI) and technetium-thallium (Tc-Tl) subtraction scanning before surgery, during which an attempt was made to identify all parathyroid glands. A scan was regarded as correct if it identified an enlarged parathyroid gland on the correct side of the neck as subsequently demonstrated at surgery. RESULTS: Ultrasonography had a sensitivity of 38 per cent (18 correct scans in 47 patients) with a positive predictive value of 78 per cent. The sensitivity of MRI was 72 per cent (34 of 47) with a predictive value of 92 per cent. Tc-Tl scanning was 60 per cent sensitive (28 of 47) with a predictive value of 85 per cent. Two patients with negative neck explorations were subsequently found to have mediastinal adenomas. CONCLUSION: Ultrasonography, MRI and Tc-Tl scanning have limited value as localization techniques and the relatively low sensitivity of these investigations means they are of no value before first-time surgery. PMID- 9361593 TI - Communicating the result of breast biopsy by telephone or in person. PMID- 9361594 TI - High serum carcinoembryonic antigen concentration in patients with colorectal liver metastases is associated with poor cell-mediated immunity, which is predictive of survival. AB - BACKGROUND: Carcinoembryonic antigen (CEA) inhibits lymphocyte function and patients with cancer have lower cell-mediated immunity (CMI) than the normal population. To test this association an investigation was made of the relationship between CMI score, CEA level and survival. METHODS: CEA level, CMI score and other variables were compared with the survival time of 109 patients with colorectal liver metastases using Cox regression analysis. RESULTS: There was a significant association between CMI and CEA categories (P = 0.04, chi 2 test). The odds of patients with normal CMI having a CEA level in the upper quartile observed for all patients were 22 per cent of those of patients with depressed CMI (odds ratio 0.22 (95 per cent confidence interval (c.i.) 0.03 0.90), mid-P corrected). The median survival time of patients with normal CMI scores was 943 days compared with 488 days for those with depressed CMI (P = 0.03, log rank test; P = 0.04, Peto). The mortality risk of patients with normal CMI at entry to the study was, in the first 2 years of treatment, 40 per cent of that of patients with depressed CMI (95 per cent c.i. for relative risk 0.20 0.82, Cox regression). CONCLUSION: In patients with colorectal hepatic metastases, CMI is predictive of survival and a raised serum CEA level is associated with depressed CMI. PMID- 9361595 TI - Liver resection in the elderly. AB - BACKGROUND: The operative mortality rate for hepatic resection in the elderly has been reported to be as high as 40 per cent for extended resection. METHODS: An increasing need to justify use of limited healthcare resources prompted a prospective assessment of 133 consecutive hepatic resections performed in 30 months in patients over 65 years of age. RESULTS: The overall mortality rate was 4 per cent. Mean(s.e.m.) hospital stay was 13(1) days, and admission to the intensive care unit was required for only eight patients. By univariate analysis, male sex (P = 0.003), preoperative jaundice (P = 0.01), abnormal preoperative electrocardiogram (P = 0.05) and poor American Society of Anesthesiologists (ASA) physical status classification (P = 0.01) were predictors of cardiopulmonary complications. In a multivariate analysis only male sex and ASA classification predicted complications (P = 0.05). The 1-, 2- and 3-year survival rates for the entire group were 78, 66 and 50 per cent respectively. All survivors returned to good functional status (mean(s.e.m.) peak postoperative Karnofsky score 95(1)). When outcome was compared with that in 244 patients younger than 65 years of age who had liver resection during the same interval, the only difference was a longer mean hospital stay for the older patients: mean(s.d.) 13.4(0.5) versus 11.9(0.4) days for those aged less than 65 years (P = 0.02). CONCLUSION: Major hepatic resection can be performed in patients over 65 years old with acceptable morbidity and mortality rates. PMID- 9361596 TI - Hepatic microcirculation during human orthotopic liver transplantation. AB - BACKGROUND: Laser Doppler flowmetry (LDF) can measure blood flow in the hepatic microcirculation. Adequate graft perfusion is essential to the outcome of organ transplantation and has not previously been measured during operation in liver transplant recipients. METHODS: LDF was carried out during operation in 22 human liver grafts after restoring portal vein and hepatic artery inflow. LDF readings were validated against liver blood flow with an electromagnetic flowmeter. Intraoperative haemodynamics and donor organ parameters known to influence graft function were correlated with LDF. RESULTS: There was a significant correlation (r = 0.96, P < 0.001) between hepatic perfusion determined with LDF and total liver blood flow measured by electromagnetic flowmetry. The perfusion measurements were reproducible with a coefficient of variation of 4 per cent. Mean(s.d.) hepatic perfusion increased significantly from baseline following venous reperfusion (17(6) versus 114(37) flux units, P < 0.001). Arterial revascularization resulted in a significant increase in mean(s.d.) perfusion (32(4)per cent, P = 0.02). There was a significant negative correlation between cold ischaemia time and graft perfusion (r = 0.48, P = 0.02; n = 22). CONCLUSION: LDF provides a reliable non-invasive method of monitoring liver graft blood flow perfusion during transplantation. PMID- 9361597 TI - Progress with cholecystectomy: improving results in England and Wales. AB - BACKGROUND: The Comparative Audit Service of the Royal College of Surgeons of England studied laparoscopic cholecystectomy in England and Wales during 1990 1991. The follow-on study undertaken during 1994 provides data to assess progress. METHODS: Pro formas were sent to consultant surgeons, requesting data on open and laparoscopic cholecystectomies performed in their units during 1994 with data on mean stay, mortality, complications, and the use of peroperative cholangiography and bile duct exploration. The identity of the consultants was treated confidentially. RESULTS: Data were provided by 110 surgeons on 4823 cholecystectomies (1019 open and 3804 laparoscopic) and outcome was compared with that of 3319 attempted laparoscopic and 8035 open cholecystectomies carried out during 1990-1991. The proportion of cases attempted laparoscopically rose from 27.2 per cent in 1990-1991 to 78.9 per cent in 1994, and conversion to open cholecystectomy rose from 5.3 to 6.7 per cent respectively. During 1994 peroperative cholangiography was undertaken in 22.9 per cent of laparoscopic and 44.6 per cent of open cases. Complication rates were similar in the two study periods, except the number of reported haemorrhagic complications was reduced by 40 per cent and bile duct injuries by fivefold (from 0.33 to 0.07 per cent). CONCLUSION: During 1994 the audit sampled approximately 10 per cent of all cholecystectomies performed in England and Wales. The results suggest progress in surgical techniques compared with findings in 1990-1991. PMID- 9361598 TI - Importance of microperineural invasion as a prognostic factor in ampullary carcinoma. AB - BACKGROUND: This was a study of the relation of clinicopathological factors to prognosis in 25 patients who had ampullary carcinoma resected. METHODS: The 5 year survival rate was six of the 25 patients. The presence of microperineural invasion was sought and related to outcome. RESULTS: Factors relating to prognosis included tumour gross appearance, diameter, pancreatic invasion and microperineural invasion. The 5-year survival rate of 14 patients with microperineural invasion was 3, significantly worse than the 7 in 11 without invasion (P = 0.002, univariate analysis). By multivariate analysis, microperineural invasion was the most important prognostic factor (P = 0.02). Type of tumour recurrence was similar to that in pancreatic carcinoma. CONCLUSION: Pancreaticoduodenectomy, rather than local resection, is the procedure of choice in patients with ampullary carcinoma. PMID- 9361599 TI - Outcome of palliative biliary and gastric bypass surgery for pancreatic head carcinoma in 126 patients. AB - BACKGROUND: Recent reports of decreased morbidity and mortality following palliative surgery for patients with irresectable pancreatic head carcinoma prompted a review of the results in 126 patients (median age 64 (range 39-90) years) who had undergone palliative biliary and gastric bypass surgery. METHODS: The indication for surgical palliation was the finding of an irresectable tumour at laparotomy (n = 44), failure of endoscopic treatment (n = 43), clinical symptoms of gastric outlet obstruction (n = 28) and miscellaneous (n = 11). Biliary and gastric bypass was performed in 118 patients, biliary bypass alone in six and gastrojejunostomy alone in two. The indication for gastrojejunostomy was symptoms in 28 patients (23 per cent) and prophylaxis in 92 patients (77 per cent). RESULTS: Postoperative local complications occurred in 17 per cent of patients, general complications in 10 per cent and delayed gastric emptying in 14 per cent of patients. The 30-day mortality rate was 1 per cent and overall hospital mortality rate 2 per cent. Median hospital stay was 17 (range 5-80) days. Median overall postoperative survival was 190 (range 14-830) days. Late obstructive gastrointestinal symptoms occurred in 14 patients (11 per cent) after a median of 141 (range 21-356) days. CONCLUSION: Roux-en-Y hepaticojejunostomy combined with gastrojejunostomy offers effective palliation for irresectable pancreatic head cancer and can be performed with low mortality and acceptable morbidity rates. PMID- 9361600 TI - Endoscopic mechanical lithotripsy of difficult common bile duct stones. AB - BACKGROUND: Mechanical lithotripsy for the management of difficult common bile duct stones has sometimes yielded conflicting results. METHODS: A series of 162 consecutive patients who underwent mechanical lithotripsy was evaluated retrospectively and a large number of variables tested for their association with successful outcome. RESULTS: The procedure was safe (morbidity rate 1.8 per cent) and effective (84.0 per cent stone clearance rate). Univariate and multivariate analysis showed that stone size was the only outcome predictor (mean(s.d.) diameter of grasped versus non-grasped stones 21.7 (6.7) versus 28.3(10.4) mm; F = 10.72, 98 d.f., P = 0.002). The cumulative probability of bile duct clearance ranged from over 90 per cent for stones with a diameter less than 10 mm to 68 per cent for those greater than 28 mm in diameter (P < 0.02). CONCLUSION: Patients at high risk of lithotripsy failure (stone diameter of 28 mm or more) might more wisely undergo surgery or other non-surgical procedures, such as extracorporeal shock-wave lithotripsy or long-term biliary stenting. PMID- 9361601 TI - Reduction of intraperitoneal adhesion formation by use of non-abrasive gauze. AB - BACKGROUND: Adhesion formation is potentially harmful. Surgical swabs may contribute to adhesions by trauma to the peritoneum. The purpose of this study was to evaluate whether standard surgical gauze (Medipres) has an adhesion promoting effect, and to determine whether a soft textile (Fastsorb), used in the electronics industry, might be less traumatic and therefore lead to less adhesion formation. METHODS: A reproducible rat model allowing semiquantitative scoring of adhesion formation was used. Three different adhesion models representing increasing degrees of peritoneal trauma (minimal, moderate and severe) were employed. The model inflicting minimal peritoneal trauma was combined with standardized rubbing of the peritoneum with surgical gauze or non-surgical textile. RESULTS: Minimal peritoneal trauma resulted in a significantly lower mean adhesion percentage (21 per cent) than moderate (44 per cent) or severe (60 per cent) peritoneal trauma (P < or = 0.005). Rubbing of the peritoneum with surgical gauze after minimal peritoneal trauma induced significantly more adhesion formation (58 versus 23 per cent, P < 0.0001). After minimal peritoneal trauma, rubbing with surgical gauze produced significantly more adhesions than rubbing with non-surgical textile (63 versus 19 per cent, P < 0.0001). Moreover, rubbing the peritoneum with non-surgical textile after minimal peritoneal trauma did not induce any additional adhesion formation (35 versus 24 per cent, P = 0.23). CONCLUSION: The extent of adhesion formation correlates significantly with the degree of peritoneal damage. Standard surgical gauze is traumatizing to the peritoneum and promotes adhesion formation whereas a less abrasive non-surgical textile does not. PMID- 9361602 TI - Choosing the proximal anastomosis in aortobifemoral bypass. AB - BACKGROUND: The preferred method of proximal aortic anastomosis (end to end or end to side) in aortobifemoral bypass remains controversial. METHODS: This is a study of 492 patients who had an aortobifemoral bypass for aortoiliac disease over 9 years in which end-to-end (166 patients) and end-to-side (326 patients) proximal aortic anastomoses were compared. The decision as to the type of anastomosis was made at operation, depending on the severity of aortic disease. Outcome was related to the site of the proximal anastomosis and the state of the distal run-off. RESULTS: The overall perioperative mortality rate was 5 per cent. Early graft occlusion occurred in six patients in the end-to-side group and none in the end-to-end group. During follow-up nine patients (5 per cent) had graft occlusion following end-to-end anastomosis and 56 (17 per cent) following end-to side anastomosis (cumulative patency 87 and 75 per cent respectively). Patency was not affected by the distal run-off. DISCUSSION: End-to-end anastomosis yields significantly better results than end-to-side anastomosis irrespective of distal run-off. PMID- 9361603 TI - Effects of serotonin and endothelin on the smooth muscle cells of autogenous vein grafts. AB - BACKGROUND: The purpose of this study was to compare the effects of vasoconstrictor substances such as 5-hydroxytryptamine (5-HT) and endothelin on the smooth muscle of canine femoral veins and vein grafts. METHODS: The right canine femoral vein was grafted into the right femoral artery. The left femoral vein was used as a control. In other experiments to examine the effects of surgical procedures such as dissection of the adventitia and the effects of grafting (vein-to-vein bypass), the right femoral vein was dissected out but not removed for grafting and an autogenous vein bypass of the right femoral vein was made using the left femoral vein. In all experiments, the veins were removed 4 weeks after operation and suspended in organ chambers for isometric tension recording. RESULTS: Maximum contractions to endothelin were comparable in control vein and vein grafts. In control vein, the maximum contraction to 5-HT was small, and was inhibited by both methiothepin, a 5-HT, and 5-HT2 antagonist, and sarpogrelate hydrochloride, a 5-HT2 antagonist. In vein grafts 5-HT produced significantly larger contractions than in control veins, which were inhibited by methiothepin but not by the 5-HT2 antagonist. In veins with adventitial dissection alone and vein-to-vein grafts, 5-HT produced small contractions which were comparable to those in control vein. CONCLUSION: The larger contraction response to 5-HT in canine vein grafts may be due to an increased responsiveness of the 5-HT1 receptor caused by grafting into the arterial circulation. PMID- 9361604 TI - Lower limb ischaemia-reperfusion injury alters gastrointestinal structure and function. AB - BACKGROUND: It has been suggested that bowel permeability is altered following abdominal aortic aneurysm surgery. The effect of ischaemia-reperfusion injury to the lower limb on the morphological structure, neutrophil infiltration and permeability of the bowel was investigated. METHODS: Histological assessment of the bowel was undertaken in five groups of Wistar rats: control, 3 h of bilateral hind limb ischaemia and 3 h of bilateral hind limb ischaemia followed by 1, 2 or 3 h of reperfusion. Using an everted gut sac model and 14C-labelled polyethylene glycol, the effect of ischaemia-reperfusion on small bowel permeability was studied. RESULTS: The small bowel showed a significant decrease in mucosal thickness, villus height and crypt depth in animals subjected to ischaemia followed by 2-hr reperfusion (mean(s.e.m.) 420(15), 217(9) and 163(6) microns respectively) compared with controls (481(11), 245(6) and 195(6) microns) (P < 0.05). Neutrophil count within the lamina propria was similar in the different groups. A significant increase in mean(s.e.m.) 14C-labelled polyethylene glycol translocation was detected in animals subjected to ischaemia-reperfusion compared with controls (760(40) versus 560(27) c.p.m. per ml per h) (P < 0.05). CONCLUSION: These data suggest that reperfusion of acutely ischaemic extremities produces structural and functional changes in the small intestine, although these changes are not associated with increased neutrophil infiltration within the bowel wall. PMID- 9361605 TI - Laparoscopy for the impalpable testis. AB - BACKGROUND: Use of laparoscopy in the management of the impalpable testis remains controversial. Localization of the testis may help plan or obviate the need for groin exploration. This study reviews the need for inguinal exploration with respect to laparoscopic findings, particularly of vas and vessels entering a closed deep inguinal ring. METHOD: Case notes of boys undergoing laparoscopy for undescended testes were reviewed retrospectively. RESULTS: Of 86 impalpable testes, 32 were intra-abdominal and ten were absent with intra-abdominal blind ending vas and vessels. In 17 instances the vas and vessels entered an open internal ring and in 26 a closed internal ring. In one boy neither vas, vessels nor testis were visualized. Of the 26 impalpable testes with a closed internal ring, excision of testicular remnants in 18 revealed no histological testicular parenchyma, one boy had bilateral perineal ectopic testes missed clinically and six were not explored. CONCLUSION: The laparoscopic finding of vas and vessels entering a closed deep inguinal ring should prompt a careful examination for an ectopic testis. If a palpable testis can be ruled out, inguinal exploration is not necessary, as viable testicular parenchyma is rarely found. Laparoscopy would have avoided negative exploration in 42 per cent of impalpable testes in this series. PMID- 9361606 TI - Detection of occult nodal metastases in patients with colorectal cancer. PMID- 9361607 TI - Retroperitoneoscopy for the diagnosis of infiltrating retroperitoneal lymphadenopathy and masses. AB - BACKGROUND: Retroperitoneoscopy (RPS) is a form of direct vision endoscopy, used to explore the retroperitoneal space, and was first described by Bartel in 1969. METHODS: RPS was performed prospectively to diagnose infiltrating retroperitoneal lymphadenopathy or masses when needle aspiration biopsy under computed tomographic guidance (NABCT) failed to establish a definite diagnosis. RESULTS: From May 1985 to August 1995, RPS was performed in 118 patients (121 procedures). Mean hospital stay was 2.4 (range 2-5) days. The peroperative and perioperative morbidity rate was 6.6 per cent of the procedures. A precise diagnosis was obtained in 108 of the 118 patients. The sensitivity was 84 per cent for malignant lymphoma, 94 per cent for Hodgkin's lymphoma, 95 per cent for metastatic lymph nodes of carcinomas and 100 per cent for primary retroperitoneal tumours. The overall sensitivity was 91.5 per cent. CONCLUSION: RPS is an alternative procedure to NABCT when aspiration biopsy is not technically feasible because a lesion is too small to sample or failed to establish a precise histopathological diagnosis. PMID- 9361608 TI - Comparison between the colonic J pouch-anal anastomosis and healthy rectum: clinical and physiological function. AB - BACKGROUND: Colonic pouch anastomosis after restorative rectal excision obviates much of the early dysfunction which is commonly experienced with the traditional straight coloanal anastomosis. A disadvantage with colonic pouch reconstruction, however, appears to be impaired evacuation. METHODS: Distal bowel function was investigated in 30 patients with a colonic J pouch anastomosis at 1 year after surgery and in 39 control subjects. RESULTS: While the degree of urgency and incontinence were similar, the patients with a pouch experienced more difficult evacuation. The maximum volume of the pouch (median 235 ml) and rectum (221 ml) was similar, but the rectum was more compliant (3.5 versus 2.6 ml per cmH2O, P < 0.01). The sensory function in terms of initial sensation of filling, urge to defaecate and maximum distension pressure was impaired in those with pouches. The amplitude of the neorectal and anal canal motility pattern was threefold that of controls. Maximum volume of the pouch was significantly associated with degree of impaired evacuation; the larger the volume the more difficult the evacuation. CONCLUSION: To reduce evacuation difficulty the pouch should not be fashioned too large. No conclusion about optimal pouch size could be drawn. In spite of fundamental physiological differences between a pouch and healthy anorectum, patients with a colonic pouch will usually experience satisfactory clinical bowel function. PMID- 9361609 TI - Outcome after multiple colorectal tumours. AB - BACKGROUND: Patients with primary colorectal cancers have a higher risk of development of second tumours synchronously or metachronously. This special group of patients raise a particular interest in their characteristics and outcome. METHODS: The records of 1009 patients with colorectal cancer were scrutinized. A group with multiple cancers was identified. Perioperative investigations, patterns of follow-up, pathological variables and outcome were noted. RESULTS: There were 22 patients with metachronous tumours and 39 with synchronous tumours following 'curative' operations in 20 and 28 respectively. There was no difference in Dukes classification between the two groups: Polyps were associated with metachronous lesions in ten of 22 patients and synchronous lesions in 17 of 39 patients. Five-year survival was 75 per cent for patients with metachronous tumours and only 18 per cent for those with synchronous tumours. CONCLUSION: In this study patients with metachronous tumours seemed to do very well while those with synchronous lesions did very badly. There were no identifiable demographic or clinical characteristics to account for this. There is a need to study this group of patients and identify factors like tumour biology or host resistance which prevent spread of tumour. PMID- 9361610 TI - Long-term results of preoperative radiation therapy alone for stage T3 and T4 rectal cancer. AB - BACKGROUND: There has been a resurgence of interest in the use of preoperative radiation therapy, with or without chemotherapy, for locally advanced rectal cancer. The purpose of this study was to analyse the time course and pattern of failure for 74 patients with clinical stage T3 or T4 (cT3-4) rectal cancer treated with preoperative radiation therapy for whom long-term follow-up was available. METHODS: Seventy-four patients with cT3-4 rectal cancer received a median of 45.0 Gy radiation alone followed by surgery 4-8 weeks later. Median follow-up was 90 months; two-thirds of patients were followed for at least 60 months. RESULTS: Following radiation therapy the pathological stage was 4 per cent pT0, 26 per cent pT1-2 and 70 per cent pT3-4. Thirty-two per cent had involved lymph nodes. The actuarial 5-year rates of local control, freedom from distant metastasis and disease-specific survival were 80, 64 and 73 per cent respectively. The corresponding 10-year rates were 73, 51 and 50 per cent. Median times to detection of local and distant recurrence were 34 and 24 months respectively. Eighty per cent of local recurrences were detected within 54 months; 80 per cent of distant recurrences were detected within 57 months. CONCLUSION: In this analysis, the time to detection of both local and distant recurrences following preoperative radiation therapy for advanced rectal cancer was surprisingly long. Almost 5 years (57 months) of follow-up were required to detect 80 per cent of all failures. The 5-year local control rate of 80 per cent compares favourably with that achieved by more aggressive chemoradiation regimens for fixed cancers; however, the high distant failure rate with radiation therapy alone suggests that adjuvant systemic therapy should be investigated. PMID- 9361611 TI - Late clinical outcome in a randomized prospective comparison of colonic J pouch and straight coloanal anastomosis. AB - BACKGROUND: Functional outcome after rectal excision with coloanal anastomosis is improved by construction of a colonic J pouch. Present prospective randomized studies lack follow-up beyond 1 year. The aim of this study was to assess the clinical outcome at both short- and long-term follow-up. METHODS: Forty patients with low rectal cancer were randomized prospectively to either J colonic pouch anal anastomosis or a straight coloanal anastomosis. Clinical assessments were performed 3, 12 and 24 months after colostomy closure using a standard questionnaire and physical examination. RESULTS: There was no significant difference in the complication rate between the two groups. There was a significant (P < 0.01) improvement in frequency of defaecation at 3, 12 and 24 months for patients with a reservoir. Similarly, fragmentation (clustering of stools) was significantly less at 3 and 12 months (P < 0.01) in the reservoir group, and incontinence occurred less frequently in the first year (P = 0.09). By 24 months no patient in either group suffered from major or minor incontinence. CONCLUSION: The functional improvement gained from a colonic reservoir in coloanal anastomosis continues to benefit the patient for at least 2 years. PMID- 9361612 TI - Soluble protein encoded by CD44 variant exons 8-10 in the serum of patients with colorectal cancer. PMID- 9361613 TI - Thermogenic, hormonal and metabolic effects of intravenous glucose infusion in human sepsis. AB - BACKGROUND: Sepsis is associated with alterations in glucose metabolism and the effect of intravenous feeding on energy expenditure is unclear. Many studies of glucose metabolism in humans with sepsis have employed techniques that are not relevant to the practice of intravenous feeding. METHODS: The thermogenic, hormonal and metabolic effects of glucose were evaluated in a prospective experimental study of septic (n = 6) and non-septic (n = 6) subjects, by administering glucose intravenously under conditions and at a rate similar to those used in total parenteral nutrition. RESULTS: Patients with sepsis had a higher fasting metabolic rate than control subjects (P < 0.001) and a lower fasting respiratory quotient (P < 0.03). The thermic effect of glucose in both groups was small and not statistically significant (median 3.2 and 0.4 per cent in septic and non-septic subjects respectively, P > 0.1). Patients with sepsis had an attenuated plasma insulin response to glucose administration compared with control subjects (P < 0.001) and less marked suppression of plasma fatty acid and glycerol concentrations (P < 0.001). Glucose administration was not associated with significant changes in plasma catecholamine concentrations in either group of patients. CONCLUSION: Intravenous infusion of glucose at clinically relevant rates is associated with a negligible thermogenic response, with no activation of the sympathetic nervous system. PMID- 9361614 TI - Influence of direction of view, target-to-endoscope distance and manipulation angle on endoscopic knot tying. AB - INTRODUCTION: The aim of the study was to investigate the influence of (1) the direction of view of the endoscope, (2) the endoscope-to-task distance and (3) the manipulation angle between the instruments on intracorporeal endoscopic knotting. METHODS: Rigid endoscopes (0 degree, 30 degrees and 45 degrees) were introduced with the objective set at distances of 50, 75, 100, 125 and 150 mm from the task. Needle holders were inserted to make 30 degrees, 60 degrees and 90 degrees manipulation angles. The execution time and knot quality parameters of 2700 knots performed by ten surgeons were obtained. RESULTS: There was no significant difference in the execution time or parameters of knot quality with different endoscopes. The longest execution time (median 95 s, P < 0.0001) and the lowest performance quality score (20.61, P < 0.001) were observed at a distance of 50 mm when compared to other distances. A 60 degrees manipulation angle had a shorter execution time (median 71 s, P < 0.0001) and a higher performance quality score (26.84, P < 0.0001) than either 30 degrees or 90 degrees manipulation angles. CONCLUSION: The direction of view of the endoscope had no significant effect on intracorporeal knotting if the optical axis subtended the same angle with the task surface. The optimal ergonomic conditions include an endoscope-to-target distance of 75-150 mm and a manipulation angle of 60 degrees. PMID- 9361615 TI - Oesophageal motility before and after laparoscopic Nissen fundoplication. AB - BACKGROUND: Whilst oesophageal manometry outcomes following fundoplication performed by open techniques have been described, detailed reports of changes in manometric parameters following large series of laparoscopic Nissen fundoplication have yet to be described. METHODS: An analysis of oesophageal manometry studies performed on patients undergoing laparoscopic Nissen fundoplication at the Royal Adelaide Hospital was performed to quantitate the effect of surgery and to determine whether manometric indicators of adverse surgical outcome could be identified. The original manometric recordings from a subset of 103 patients were reviewed. Only patients who had undergone preoperative and postoperative examinations in this department, and assessment by an independent investigator using a standardized clinical questionnaire, were included in the study. RESULTS: Mean resting lower oesophageal sphincter (LOS) pressure increased from 8.5 to 21.5 mmHg (P < 0.0001) following surgery, the mean residual pressure after sphincter relaxation (residual relaxation pressure) increased from 1.2 to 10.8 mmHg (P < 0.0001), and oesophageal 'ramp' pressure increased from 10.5 to 20.5 mmHg (P < 0.0001). Before operation 88 patients (85 per cent) propagated seven or more of ten wet swallows (normal peristalsis) versus 83 (81 per cent) after operation. Of the 15 patients with abnormal peristalsis before surgery, eight regained normal peristalsis after operation, whereas 13 of 88 patients with normal preoperative peristalsis subsequently had defective postoperative peristalsis. Raised postoperative residual relaxation pressure (r = 0.20) but not LOS pressure correlated significantly with postoperative dysphagia for liquids. None of the measured manometric parameters correlated with adverse outcomes such as postoperative dysphagia for solids, patient dissatisfaction or gas bloat. CONCLUSION: Whilst this study documents significant changes in LOS pressure following laparoscopic Nissen fundoplication, a clinically significant correlation between manometric outcome and clinical outcome was not demonstrated. PMID- 9361616 TI - Early adenocarcinoma in Barrett's oesophagus. AB - BACKGROUND: The results of surgical treatment in 41 patients with early adenocarcinoma of the oesophagus were analysed retrospectively. METHODS: The treatment of choice was transhiatal radical subtotal oesophagectomy (n = 38); in three patients with adenocarcinoma in the mid or upper thoracic portion of the oesophagus, right transthoracic en bloc oesophagectomy was performed. RESULTS: One patient died within 30 days and another within 90 days (4.8 per cent). All tumours were resected completely. Multicentricity of adenocarcinoma in Barrett's oesophagus was detected in six cases and high-grade dysplasia in 28. Some 31 patients had infiltration of the submucosa, whereas in ten, carcinoma was limited to the mucosa. No patient with mucosal adenocarcinoma had lymph node metastases, whereas five of the 31 with submucosal infiltration showed lymph node involvement. The 5-year survival rate of the total group of 41 patients, including postoperative mortality, was 83 per cent. All ten patients with adenocarcinoma limited to the mucosa (pT1a) were alive at 5 years; of 31 with submucosal infiltration (pT1b) 79 per cent survived to 5 years (P not significant). Patients without lymph node metastasis had a 5-year survival rate of 81 per cent, compared with 50 per cent for those in the pN1 category (P not significant). CONCLUSION: Oesophagectomy for early oesophageal adenocarcinoma is safe and leads to a favourable long-term prognosis. PMID- 9361618 TI - Perianal sepsis in children. PMID- 9361617 TI - Population-based study of diagnosis, treatment and prognosis of gastric cancer. AB - BACKGROUND: Gastric cancer remains a common cancer with a poor prognosis. Improving trends seen in Japan have not yet been observed in Western countries. METHODS: A population-based series of 1329 patients with gastric cancer diagnosed over an 18-year period in Cote d'Or, France, was used to establish time trends in diagnostic strategy, treatment and prognosis. RESULTS: The use of endoscopy alone increased from 2.7 per cent in 1976-1978 to 76.6 per cent in 1991-1993 (P < 0.0001). This trend was associated at first with a significant decrease in the use of radiography alone, then by a significant decrease in the use of both radiography and endoscopy. The proportion of resections for cure increased from 37.9 per cent in 1976-1978 to 50.0 per cent in 1991-1993 (mean 3-year variation + 5.8 per cent, P < 0.01). The proportion of cases confined to the gastric wall increased from 6.1 to 11.7 per cent (mean 3-year variation + 13.1 per cent, P < 0.01), while the proportion of other stages remained stable. The operative mortality rate decreased dramatically from 25.6 per cent in 1976-1978 to 13.6 per cent in 1991-1993 (P < 0.001) and the 5-year relative survival rate rose from 12.8 per cent in 1976-1978 to 26.4 per cent in 1988-1990 (P < 0.001). CONCLUSION: This study has demonstrated that improvements in the care of patients with gastric cancer have been achieved, but that further progress may be made. PMID- 9361619 TI - Endothelin 1 is a mediator of intimal hyperplasia in organ culture of human saphenous vein. PMID- 9361620 TI - Major vascular injury during laparoscopy. PMID- 9361621 TI - Laparoscopic surgery is associated with less tumour growth stimulation than conventional surgery: an experimental study. PMID- 9361622 TI - Herniography for groin pain of uncertain origin. PMID- 9361623 TI - Experimental study in bile duct-ligated rats of vasopressin and preoperative volume loading to prevent hypotensive crises. PMID- 9361624 TI - Computed tomography in acute left colonic diverticulitis. PMID- 9361626 TI - Myths in management of colorectal malignancy. PMID- 9361625 TI - Contraindication for the use of neostigmine in colonic pseudo-obstruction. PMID- 9361627 TI - Myths in management of colorectal malignancy. PMID- 9361628 TI - Myths in management of colorectal malignancy. PMID- 9361629 TI - Universal syringe registration? PMID- 9361630 TI - Unlike any other procedure. PMID- 9361631 TI - Methadone maintenance: BC leads the way. PMID- 9361632 TI - Helicobacter pylori: corrections and comments. PMID- 9361633 TI - Helicobacter pylori: corrections and comments. PMID- 9361634 TI - Needle exchange programs. PMID- 9361635 TI - Safe havens for addicted mothers. PMID- 9361636 TI - Safe havens for addicted mothers. PMID- 9361637 TI - Safe havens for addicted mothers. PMID- 9361638 TI - Cutting immunization aid: penny wise, pound foolish? PMID- 9361639 TI - Effect of breast self-examination techniques on the risk of death from breast cancer. AB - OBJECTIVE: To measure the effect of breast self-examination (BSE) technique and frequency on the risk of death from breast cancer. DESIGN: Case-control study nested within the Canadian National Breast Screening Study (NBSS). SETTING: The Canadian NBSS, a multicentre randomized controlled trial of screening for breast cancer in Canadian women. SUBJECTS: The case subjects were 163 women who had died from breast cancer and 57 women with distant metastases. Ten control subjects matched by 5-year age group, screening centre, year of enrolment and random allocation group were randomly selected for each case subject. EXPOSURE MEASURES: Self-reported BSE frequency before enrolment in the NBSS, annual self-reports of BSE frequency during the program and annual objective assessments of BSE technique. OUTCOME MEASURES: Odds ratios (ORs) associated with BSE practice were estimated by conditional multiple logistic regression modelling, which permitted control of covariates. RESULTS: Relative to women who, when assessed 2 years before diagnosis, examined their breasts visually, used their finger pads for palpation and examined with their 3 middle fingers, the OR for death from breast cancer or distant metastatic disease for women who omitted 1, 2 or 3 of these components was 2.20 (95% confidence interval [CI] 1.30 to 3.71, p = 0.003). The OR for women who omitted 1 of the 3 components was 1.82 (95% CI 1.00 to 3.29, p = 0.05), for those who omitted 2 of the 3 components, 2.84 (95% CI 1.44 to 5.59, p = 0.003), and for those who omitted all 3 components, 2.95 (95% CI 1.19 to 7.30, p = 0.02). The results remained unchanged after adjustment for potential confounders. CONCLUSION: The results, obtained with the use of prospectively collected data, suggest that the performance of specific BSE components may reduce the risk of death from breast cancer. PMID- 9361640 TI - Needs-based planning: the case of Manitoba. AB - OBJECTIVE: To illustrate the use of needs-based planning in the identification of physician surpluses and deficits and of resource misallocations within a provincial medical system at a time when provincial governments and medical associations across the country are faced with funding constraints for physician services. DESIGN: For each of 4 regions in Manitoba, the authors analysed residents' rates of physician visits (whether within the resident's own or another region). Residents' need for physician contact was estimated by means of a statistical analysis of the data on contacts in relation to age, sex and health related indicators, and the rates of visits needed and actually made were compared. PARTICIPANTS: All Manitoba residents. OUTCOME MEASURES: Numbers of generalist physicians (general practitioners, family physicians, general internists and general pediatricians) needed to serve each region, and the extent of physician surplus and deficit in each region. RESULTS: There appeared to be a surplus of physicians in most of urban Manitoba but deficits in northern Manitoba and some parts of the rural south. General internists and general pediatricians in Winnipeg provide a significant part of the ambulatory care that is provided by general practitioners in other parts of the province. The provincial government currently spends more per resident to provide physician services in areas of physician surplus than in areas of physician deficit, although the patterns are inconsistent. CONCLUSIONS: Needs-based planning is possible. If provinces are intent on controlling physician numbers and expenditures, it makes sense to manage the implications of doing so. PMID- 9361641 TI - Is breast self-examination still necessary? PMID- 9361642 TI - Physician resource planning in an era of uncertainty and change. PMID- 9361643 TI - Physician resource planning: ways and means. PMID- 9361644 TI - Human rights, ethics and the Krever inquiry. PMID- 9361645 TI - Management of women at increased risk for breast cancer: preliminary results from a new program. AB - OBJECTIVE: To examine the characteristics of malignant tumours that develop in women undergoing surveillance for increased risk for breast cancer and to identify presentation patterns in order to determine the respective roles of mammography, clinical breast examination (CBE) and breast self-examination (BSE). SETTING: Breast Diagnostic Clinic and Familial Breast Cancer Clinic at Toronto Sunnybrook Regional Cancer Centre. PARTICIPANTS: A total of 1044 women evaluated for breast cancer risk from Oct. 1, 1990, to Dec. 31, 1996, of whom 381 were categorized as being at high risk, 204 as being at moderate risk, 401 as being at slightly increased risk and 58 as being at no appreciably increased risk. PROGRAM COMPONENTS: Comprehensive review and discussion of risk factors, clinical assessment, surveillance recommendations that include mammography, CBE and BSE, genetics consultation (Familial Breast Cancer Clinic) and psychosocial support. Data are captured prospectively, updated at each visit and audited every 3 to 6 months. PROGRAM OUTCOMES: During the study period breast cancer was diagnosed in 24 patients, 12 in the high-risk group, 4 in the moderate-risk group and 8 in the group at slightly increased risk. The mean age at diagnosis was 47 (range 32 to 82) years. Ten cases of cancer were diagnosed during surveillance (incident cancer), 5 in women under age 50. The mean length of time from initial assessment to diagnosis was 28.6 (range 12 to 51) months. Of the 24 women, 17 reported a family history of breast cancer. The mean age at diagnosis in this cohort was 45.5 years, and the diagnosis was made under age 50 in 10 patients (59%). The mean earliest age at which breast cancer was diagnosed in a family member was 42.5 years. CONCLUSIONS: These preliminary results suggest that surveillance of women at increased risk for breast cancer may be useful in detecting disease at an early stage. The regular performance of mammography, CBE and BSE appears necessary to achieve these results. PMID- 9361647 TI - Recognizing and controlling respiratory disease outbreaks in long-term care facilities. PMID- 9361648 TI - New York hospitals paid to teach fewer physicians. AB - In order to reduce the number of physicians being trained in the US, teaching hospitals in New York are going to be paid not to train residents. Participating hospitals will cut the number of residents they train by up to 25%, but for a time will be paid as if they are still teaching a full complement of trainees. Up to 400 residency positions will be cut annually under the plan. PMID- 9361649 TI - Krever can name names, Supreme Court rules. PMID- 9361650 TI - Bills for noninsured services remain a wellspring for patients' complaints. AB - Why do many canadians become angry when told they have to pay for noninsured medical services? Dorothy Grant hears many protests about this type of billing in her job with the Medical Society of Nova Scotia. Here she describes steps doctors can take to reduce the number of complaints. PMID- 9361646 TI - Report of the Canadian Hypertension Society Consensus Conference: 3. Pharmacologic treatment of hypertensive disorders in pregnancy. AB - OBJECTIVE: To provide Canadian physicians with evidence-based guidelines for the pharmacologic treatment of hypertensive disorders in pregnancy. OPTIONS: No medication, or treatment with antihypertensive or anticonvulsant drugs. OUTCOMES: Prevention of maternal complications, and prevention of perinatal complications and death. EVIDENCE: Pertinent articles published from 1962 to September 1996 retrieved from the Pregnancy and Childbirth Module of the Cochrane Database of Systematic Reviews and from MEDLINE; additional articles retrieved through a manual search of bibliographies; and expert opinion. Recommendations were graded according to levels of evidence. VALUES: Maternal and fetal well-being were equally valued, with the belief that treatment side effects should be minimized. BENEFITS, HARMS AND COSTS: Reduction in the rate of adverse perinatal outcomes, including death. Potential side effects of antihypertensive drugs include placental hypoperfusion, intrauterine growth retardation and long-term effects on the infant. RECOMMENDATIONS: A systolic blood pressure greater than 169 mm Hg or a diastolic pressure greater than 109 mm Hg in a pregnant woman should be considered an emergency and pharmacologic treatment with hydralazine, labetalol or nifedipine started. Otherwise, the thresholds at which to start antihypertensive treatment are a systolic pressure of 140 mm Hg or a diastolic pressure of 90 mm Hg in women with gestational hypertension without proteinuria or pre-existing hypertension before 28 weeks' gestation, those with gestational hypertension and proteinuria or symptoms at any time during the pregnancy, those with pre-existing hypertension and underlying conditions or target-organ damage, and those with pre-existing hypertension and superimposed gestational hypertension. The thresholds in other circumstances are a systolic pressure of 150 mm Hg or a diastolic pressure of 95 mm Hg. For nonsevere hypertension, methyldopa is the first-line drug; labetalol, pindolol, oxprenolol and nifedipine are second-line drugs. Fetal distress attributed to placental hypoperfusion is rare, and long-term effects on the infant are unknown. Magnesium sulfate is recommended for the prevention and treatment of seizures. VALIDATION: The guidelines are more precise but compatible with those from the US and Australia. PMID- 9361651 TI - Despite some PR fallout, proponents say MD walkouts increase awareness and may improve health care. AB - This fall Ontario braced for possible strikes by public servants and teachers. A year earlier, the province's physicians were preparing their own job action. Walkouts by physicians, which have not been uncommon since the introduction of medicare, create two camps. In one are physicians who say legal job actions are ethical and often improve health care for patients. In the other are some doctors and ethicists who question whether doctors have an ethical right to withdraw services, even if it is legal to do so. Nicole Baer interviewed members of both camps. PMID- 9361652 TI - Self-help medical advice was popular in the 1930s, too. AB - Self-help books proliferate today, but the concept of helping oneself in health matters is certainly not a modern phenomenon, Dr. Mark Clarfield notes. He recently studied a self-help booklet from 1936, What to do until the doctor comes, in which he found not only some sound advice but also some harmless suggestions, useless treatments and dangerous remedies. PMID- 9361653 TI - Atrial fibrillation in older stroke patients: association with recurrence and mortality after first ischemic stroke. AB - OBJECTIVES: The objective of this study was to determine the association of atrial fibrillation (AF) with stroke recurrence and mortality and with the causes of death in ischemic stroke patients aged 75 years and older. DESIGN: A population-based study. SETTING: The cities of Turku and Kuopio in Finland. PARTICIPANTS: The study cohort consisted of 2635 consecutive patients aged 75 years and older, with a first ischemic stroke, registered in the FINMONICA Stroke Register. MEASUREMENTS: 28-day and 1-year stroke mortality, causes of death, and recurrence of stroke. RESULTS: There were 767 stroke patients with AF (mean age 82.2) and 1868 patients without AF (mean age 81.4). Mortality was higher in the AF group both 28 days (33.9% vs 28.1%, P = .003) and 1 year after the attack (52.7% vs 43.0%, P < .001). The age- and sex-adjusted relative risk of death at 28 days was 1.25 in the AF group (95% confidence interval (CI) 1.04-1.50, P = .018), and at 1 year it was 1.41 (95% CI 1.18-1.67, P < .001). In a Cox proportional hazards model, 1-year mortality risk comparing the AF-group with non AF group was 1.24 (95% CI 1.10-1.39, P < .001). The strongest risk factor predicting 1-year mortality was recent myocardial infarction (MI) (RR 1.90, 95% CI 1.49-2.42). Myocardial infarction was more often the underlying cause of death in the AF group during the period of 28 days, but not from 28 days up to 1 year. The 1-year recurrence rate among those alive at day 28 was 11.5% in the AF group and 9.4% in the non-AF group (P = .240). CONCLUSION: Recent MI and AF are independent negative prognostic factors in older patients with stroke. Although the relative risk estimates attributable to AF are of the same magnitude in older as in middle-aged stroke patients, the much higher prevalence of AF in the older patients emphasizes its absolute impact on the mortality and recurrence after the first ischemic stroke in the age group 75 years and older. The treatment of coexisting cardiac disease also has the potential to prevent deaths and recurrent stroke events in older persons. PMID- 9361654 TI - Factors predicting fractures during falling impacts among home-dwelling older adults. AB - OBJECTIVE: To investigate the predictors of fractures during falling impacts among home-dwelling older adults. DESIGN: A case-control study within a prospective, population-based survey. SETTING: Five rural municipalities in northern Finland. PARTICIPANTS: The study population consisted of all home dwelling persons aged 70 or older living in these five municipalities (n = 790 (85%)). The cases for this study were those with fracture, using the first fracture (n = 82) in the analyses, during a follow-up period of 4 years. Controls (n = 82) were selected from among the persons who suffered soft tissue injuries; matching was by age, sex, and location of the first injury during the period. MEASUREMENTS: During a 4-year follow-up period, all falls in the population were recorded using fall diaries, telephone interviews, and information from medical records. Risk factors for fractures during the 4-year follow-up were determined according to the number and severity of previous falls, circumstances and place of falls, disease history, use of medicines, symptoms, clinical examinations and tests, nutritional status, functional abilities and social and health behavior. Cross-tabulations for categorial variables, paired t tests for the means of continuous variables, and conditional logistic regression analysis were performed. RESULTS: According to the bivariate analyses, the risk factors for falls resulting in a fracture were frequent fear of falling, abnormal heel-shin test, reduced knee extension strength, reduced grip strength, poor distance visual acuity, low supine pulse rate, inability to carry a 5-kg load 100 meters, not doing heavy outdoor work, and no habitual exercise. A limited amount of social participation was associated negatively with fracturing. Conditional logistic regression analysis showed that the risk factors for fracture-causing falls were frequent fear of falling (OR 2.50; CI 1.11-5.65), reduced knee extension strength (OR 3.38; CI 1.00-11.4), and poor distance visual acuity (OR 3.45; CI 1.13-10.6), whereas limited social participation (OR 0.29; CI 0.11-0.79) protected against the occurrence of fractures. CONCLUSION: Impaired perception, muscle strength, and psychological and social functioning may influence fracture risk during injurious fall impacts. Studies with larger sample sizes are needed to confirm this and to examine the circumstances and mechanisms contributing to the fracture risk during falls via these risk factors. PMID- 9361655 TI - Mammography underutilization among older women in Connecticut. AB - OBJECTIVES: The primary goals were to examine mammography use rates among older women in Connecticut and to determine if there was significant variation among different areas and racial groups in the state. The secondary goal was to examine what impact the initiation of Medicare reimbursement for mammography screening has had on mammography use. DESIGN: Statewide use rates were determined by retrospective Medicare Part B mammography claims analysis. Small area analysis methodology (SAA) was used to identify mammography rates for 23 hospital service areas (HSAs), representing all of the catchment areas for Connecticut's acute care hospitals. PARTICIPANTS: Female Medicare beneficiaries 65 years and older with Part B coverage residing in Connecticut during the study period. MEASUREMENTS: The main outcome (the use of at least one mammogram) was calculated for the calendar years 1991, 1992, and 1993. Mean annual use rates in 1993 were generated for the 23 HSAs and the different racial groups in Connecticut. To examine the effect that Medicare reimbursement for screening mammograms has had on mammography use, rates were calculated for women who met Medicare reimbursement criteria in 1991 through 1993. The rates in 1992 and 1993 were then compared with those in 1991, when the reimbursement program was first initiated. MAIN RESULTS: The mean statewide annual rates among women aged 65 years and older were 23.4% (1991), 24.5% (1992), and 24.9% (1993). The mammography use rates among black women 65 years and older were significantly lower than their white peers in 1991 (18.8% black vs 23.8% white, P < .001), 1992 (20.6% vs 24.7%, P < .001), and 1993 (22.0% vs 25.1%, P < .001). Significant variation was identified among hospital service areas (HSAs) within the state for each time interval studied. The use rates among women aged 65 years and older who were eligible for Medicare screening mammography reimbursement increased significantly from 14.6% in 1991, when Medicare reimbursement for screening mammograms was first initiated, to 18.9% in 1992 (P < .001). The rates in 1993 (17.4%) also increased from the baseline year 1991 (P < .001). However, the observed increases since 1991 have been limited in magnitude. CONCLUSIONS: Low mammography use persists among older women in Connecticut and, in particular, among older black women. The initiation of Medicare reimbursement for screening mammograms in 1991 has had some impact on mammography use although its effects are still limited. Through the use of small area analysis methodology, significant underutilization of mammography in localized areas of the state was identified. These findings have facilitated local outreach interventions. Additional research is needed to understand if health service barriers are contributing to the local variation in rates observed in this study. PMID- 9361656 TI - Dental status, quality of life, and mortality in an older community population: a multivariate approach. AB - OBJECTIVE: To evaluate the relationships between a functional measure of dental status (FDS), several variables belonging to a quality of life (QOL) profile, and mortality in an older community population. DESIGN: Cross-sectional analysis for FDS and QOL; 10-year prospective study for mortality. SETTING: The historical and central district of the city of Brescia, northern Italy. PARTICIPANTS: The entire cohort of 70 to 75-year-old people living in the above-mentioned district (n = 1303): 1201 subjects were eligible for interview at baseline; 11 refused the physical examination; 52 were lost to follow-up; data are presented for the remaining sample of 1137 subjects. MEASUREMENTS: FDS examination was used to classify the subjects into three groups: naturally adequate (ADS) (25.2%), naturally inadequate (IDS) (14.3%) dental status, and denture wearers (DW) (60.4%). Various QOL domains were assessed: mood level, cognitive status, instrumental activities of daily living (IADL), social relationships, indexes of somatic health, and health behaviors. The demographic and socioeconomic parameters were used as covariates. RESULTS: Univariate analysis showed that both the ADS and the DW groups had a better QOL profile than the IDS group. Multiple logistic regression indicated that ADS and DW conditions were predicted independently by better educational and financial conditions, higher social relationships and a better IADL level in comparison with IDS. Moreover, compared with IDS, DS was a significant predictor of a better level at the SELF, IADL, and HCU scales whereas DW predicted only a better IADL level. Crude survival analysis showed that ADS was associated with a lower mortality risk compared with both DW and IDS, which did not differ from each other. FDS also remained a significant and independent predictor of mortality in a more general Cox's regression model. CONCLUSIONS: Within this cohort of 70 to 75-year-old urban residents, FDS is associated with several QOL domains and with long-term survival. A hierarchy of reciprocal relationships exists among these parameters. The present study provides a basis for encouraging more extensive use of dentures. Longitudinal studies using oral health outcomes are warranted before clinical recommendations can be made. PMID- 9361657 TI - Factors associated with cognitive impairment among older Italian inpatients. Gruppo Italiano di Farmacovigilanza nell'Anziano (G.I.F.A.). AB - OBJECTIVE: To examine the association of cognitive impairment with educational, demographic, and nutritional variables in older hospitalized people. DESIGN: Survey of older patients admitted consecutively to a hospital during two 2-month periods in 1993. SETTING: Patients admitted for general medical care at 35 hospitals participating in the GIFA study throughout Italy. PARTICIPANTS: A total of 3628 patients aged 65 or older were studied. MEASUREMENTS: The Hodkinson Abbreviated Mental Test (HAMT) was used as a screening method to assess the patients' basic cognitive function. Multiple logistic regression was used to examine the association between cognitive impairment and demographic, educational or nutritional variables. RESULTS: Twenty-nine percent of older inpatients were classified as having cognitive impairment, with similar distribution of HAMT score found in both genders. Educational attainment has a highly significant inverse relationship with cognitive impairment (highest education: OR 0.32; 95% CI 0.20-0.52). Moreover, cognitive impairment decreased with increasing body mass index (3rd tertile: OR 0.69; 95% CI: 0.51-0.93), cholesterol serum level (highest values: OR 0.59; 95% CI 0.37-0.93), circulating lymphocytes (highest values: OR 0.55; 95% CI 0.45-0.69), and serum albumin (highest values: OR 0.60; 95% CI 0.47 0.76), with a gradient of influence for each variable. CONCLUSIONS: Educational attainment affects cognitive function in older inpatients. The strong association between cognitive impairment and nutritional variables suggests that every effort to improve nutritional status is needed in approaching cognitive impairment in older patients. PMID- 9361658 TI - Noncognitive disturbances in Alzheimer's disease: frequency, longitudinal course, and relationship to cognitive symptoms. AB - OBJECTIVE: To investigate the frequency and longitudinal course of symptoms of depression, agitation, and psychosis in a longitudinally studied sample of patients with Alzheimer's disease (AD). DESIGN: Longitudinal study of AD patients with follow-up assessments at 6-month intervals for an average of more than 3 years. SETTING: Alzheimer's Disease Research Center of the Mount Sinai Medical Center and the Bronx VA Medical Center, New York. PARTICIPANTS: A total of 153 AD patients. MEASUREMENTS: Blessed Test of Information, Memory and Concentration (BIMC) and the Alzheimer's Disease Assessment Scale cognitive (ADAS-Cog) and noncognitive (ADAS-NC) subscales. RESULTS: At entry into the study, more than 90% of patients had a behavioral disturbance that was rated as mild or worse on one of the 10 ADAS noncognitive items; and 40% had at least one rating that was moderate or severe. Correlational analyses indicated that, with the exception of the two mood-related items, noncognitive symptoms on the ADAS were not highly correlated with one another. Only one of the noncognitive items, concentration, was strongly correlated with the severity of cognitive impairment. On average, patients showed progressively worse cognitive functioning over time as measured both by the ADAS-Cog and the BIMC. The mean severity of noncognitive symptoms did not change during the course of a 5-year follow up. The severity of behavioral disturbance at any one evaluation was negatively correlated with change in behavior during the next 6 months and was not correlated with cognitive decline. CONCLUSION: Mild behavioral disturbances are common, whereas moderate to severe behavioral symptoms are less frequent in this population of AD patients. Disturbances in mood and manifestations of agitation and psychotic symptoms are not closely related to one another and show little progressive worsening over time. Rather, they tend to be episodic such that increasing severity at one time is usually followed by improvement later. Concentration problems are a manifestation of cognitive dysfunction rather than behavioral disturbance in AD. Implications of these results for treatment of noncognitive disturbances in AD are discussed. PMID- 9361659 TI - What is wrong with end-of-life care? Opinions of bereaved family members. AB - OBJECTIVE: To describe family perceptions of care at the end of life. METHODS: In a representative sample of older people who died from chronic diseases, family members were interviewed about satisfaction with treatment intensity, decision making, and symptom relief in the last month of life, and gave suggestions to improve care. RESULTS: Interviews were completed with 461 family members, 80% of those contacted. They reported that 9% of decedents received CPR, 11% ventilator support, and 24% intensive care during their last month of life. Family members could not recall a discussion of treatment decisions in 23% of cases. Presence or absence of a living will did not affect the likelihood of no discussion (22% vs 24%, P = .85). Family informants desired more treatment to sustain life in 8% of deaths. They or the decedent wanted treatments doctors did not recommend in 6% of deaths but refused recommended therapies in 18% of deaths. They believed more care to relieve pain or other symptoms was indicated in 18% of deaths. Asked to make positive or negative comments about any aspect of terminal care, 91% of comments on hospice were positive. Nursing home care received the smallest proportion of positive comments (51%). Family members recommendations to improve end of life care emphasized better communication (44%), greater access to physicians' time (17%), and better pain management (10%). CONCLUSION: Bereaved family members are generally satisfied with life-sustaining treatment decisions. Their primary concerns are failures in communication and pain control. Discussions that focus on specific treatment decisions may not satisfy the real needs of dying patients and their families. PMID- 9361660 TI - Validation of multi-frequency bioelectrical impedance analysis in detecting changes in fluid balance of geriatric patients. AB - OBJECTIVES: Multi-Frequency Bioelectrical Impedance Analysis (MFBIA) is a quick, simple, and inexpensive method to assess body fluid compartments. This study aimed at determining the validity of MFBIA in detecting clinically relevant changes of fluid balance in geriatric patients. DESIGN: A prospective, observational study. SETTING: The 22-bed Geriatric Department of the University Hospital Nijmegen. PARTICIPANTS: Hospitalized patients were eligible if they did not have a pacemaker, were not suffering from terminal illnesses, and did not have psychogeriatric diseases likely to interfere with capacity to consent or comply. During a 16-months period, 218 patients were admitted, of whom 78 patients were eligible and 53 consented to participate. MEASUREMENTS: Each subject's fluid balance was diagnosed twice a week as dehydrated, overhydrated, or euvolemic, based on standardized physical examination, laboratory tests, and weight evaluation. Changes in fluid balance were quantified by measuring total body water (TBW) and extracellular fluid (ECF) applying deuterium- and bromide dilution techniques. Impedance at 1, 5, 50, and 100 kHz and body weight were measured daily. Sensitivity and Guyatt's responsiveness indexes of MFBIA in detecting dehydration and overhydration were determined. RESULTS: In total, 1071 MFBIA measurements were performed, during which 14 transitions from dehydration to euvolemia and 13 transitions from overhydration to euvolemia were monitored. Rehydration of dehydrated patients caused an increase in TBW and ECF of 3.4 +/- 1.8 L and 1.9 +/- 1.9 L, respectively, which resulted in significant decreases in impedance of 133 +/- 67 omega at 1 kHz and 93 +/- 61 omega at 100 kHz (P = .001). Treatment of overhydrated patients caused a TBW and ECF loss of 3.8 +/- 4.2 L and 3.1 +/- 3.8 L, respectively, which resulted in significant increases in impedance of 104 +/- 72 omega at 1 kHz and 81 +/- 68 omega at 100 kHz (P < .001). Sensitivity of a single MFBIA in diagnosing dehydration and overhydration was 14% and 17%, respectively. Responsiveness indexes of weighing and MFBIA for dehydration and overhydration were similar at all frequencies and greater than one. CONCLUSION: The sensitivity of a single impedance measurement in detecting dehydration and overhydration was low. However, responsiveness of serial measurements to intra-individual changes in fluid balance was good. Therefore, this noninvasive technique may be used in clinical practice to improve monitoring fluid balance in geriatric patients, especially when daily weighing is difficult. PMID- 9361661 TI - Validation of a Telephone Cognitive Assessment Battery. AB - OBJECTIVE: To present and evaluate an instrument, the Telephone Cognitive Assessment Battery (TCAB), designed to be administered over the telephone to assess the cognitive status of older individuals. The TCAB addresses mental status, reasoning and executive ability, primary and secondary memory, and language. It consists of six neuropsychological tests and takes approximately 15 to 20 minutes to complete. DESIGN: The instrument is evaluated with a comparative cross-sectional design, with data collected both prospectively and retrospectively. SETTING: The University Hospitals of Cleveland/Case Western Reserve University Alzheimer Center Research Registry. PARTICIPANTS: Forty Alzheimer's Disease cases selected from among those most recently recruited into the Registry and 40 cognitively intact Registry controls. Controls were selected randomly so that the two groups had similar distributions of age, sex, and education. MEASUREMENTS: The cognitive status of all participants was assessed utilizing both the TCAB and the usual in-person Registry evaluation, which includes medical history data and in-person assessment of cognitive status. In order to measure the potential learning effect of repeated testing, half of the cases and half of the controls were recruited and assessed over the telephone with the TCAB before their in-person Registry evaluation (with a waiting period of at least 2 weeks between evaluations), whereas the other two halves received the TCAB after they had become part of the Registry. The TCAB was administered to all participants by a single investigator. Two clinical evaluators, blinded to the Registry diagnosis of the subjects, independently classified the subjects as cognitively impaired, normal, or questionable on the basis of the results of the TCAB and a brief listing of medical illness and depressive symptoms. A final classification was achieved through consensus and subsequently compared with the Registry diagnosis, taken here to be the gold standard. RESULTS: Test scores of subjects assessed by TCAB before receiving the in-person assessment were compared with those of subjects receiving the in-person assessment first. There were no significant differences between mean scores of the two groups (those with TCAB first and those with TCAB last) for either cases or normal controls. High values of the kappa statistic were obtained for the two initial evaluators of the TCAB classification, demonstrating excellent interrater reliability. Regarding the reconciled TCAB classification, the ability of the TCAB to correctly classify subjects according to cognitive status, while controlling for potential confounders such as age and educational level, was assessed by means of discriminant analysis techniques. Knowledge of the TCAB classification and age allowed the correct classification of 95% of the participants; this was not significantly improved by knowledge of other potential determinants. Sensitivity and specificity were calculated under two schema for classifying those subjects in the "questionable" category. Positive and negative predictive values of the TCAB were computed assuming a prevalence of cognitive impairment of 10% in the older population. High negative predictive values (over 99%) were obtained under both schema, whereas the positive predictive values were seen to be more dependent on the classification of questionables. CONCLUSION: Research studies involving ascertainment of cognitive status of older people, particularly those that require periodic follow-up, such as those focusing on healthy aging, commonly suffer from lack of representativeness of subjects, often brought about by problems related to mobility of potential participants. It is also crucial that normal individuals who are recruited initially to serve as controls in epidemiologic studies of dementing illnesses be reevaluated periodically, and this may be hindered by the same obstacles. (ABSTRACT TRUNCATED) PMID- 9361662 TI - Underutilization of beta-blockers in older patients with prior myocardial infarction or coronary artery disease in an academic, hospital-based geriatrics practice. AB - OBJECTIVE: To investigate the prevalence of beta-blocker use in older persons with prior myocardial infarction (MI) or coronary artery disease (CAD) without contraindications to beta-blockers in an academic hospital-based geriatrics practice. DESIGN: A retrospective analysis of charts from all older patients seen during January 1996 through March 1997 at an academic, hospital-based geriatrics practice was performed to investigate the prevalence of beta-blocker use in older patients with prior MI or CAD without contraindications to beta blockers. SETTING: An academic, hospital-based, primary care geriatrics practice staffed by fellows in a geriatrics training program and full-time faculty geriatricians. PATIENTS: One hundred thirty-nine women and 84 men, mean age 82 +/- 8 years (range 67 to 96), were included in the study. MEASUREMENTS AND MAIN RESULTS: Of 233 patients with CAD, 53 patients (23%) were receiving beta-blockers. Of 180 patients with CAD not receiving beta-blockers, 34 patients (19%) had contraindications to beta-blockers. Of 199 patients with CAD without contraindications to beta-blockers, 53 patients (27%) were receiving beta blockers. Of 162 patients with prior MI, 38 patients (23%) were receiving beta blockers. Of 124 patients with prior MI not receiving beta-blockers, 19 patients (15%) had contraindications to beta-blockers. Of 143 patients with prior MI without contraindications to beta-blockers, 38 patients (27%) were receiving beta blockers. CONCLUSIONS: There is marked underutilization of beta-blockers in treating older patients with prior MI or CAD in an academic, hospital-based geriatrics practice. PMID- 9361663 TI - The soluble interleukin-2 receptor predicts mortality in older hospitalized men. AB - BACKGROUND: There is an inverse relationship between the soluble interleukin-2 receptor (sIL-2R) and serum albumin, cholesterol, transferrin, prealbumin, and hemoglobin. Inasmuch as low serum albumin and cholesterol have been associated with excess mortality, we hypothesized that elevated sIL-2R would predict mortality in older adults. OBJECTIVE: To determine if elevated sIL-2R predicts mortality in patients on a geriatric rehabilitation unit. DESIGN: Prospective cohort. SETTING: University-affiliated VA medical center. PARTICIPANTS: Seventy two male patients aged greater than 60 years admitted to a geriatric rehabilitation unit. Patients with severe hepatic or renal disease were excluded. MEASUREMENTS: We measured serum albumin, prealbumin, cholesterol, transferrin, hemoglobin, body mass index (BMI), C-reactive protein (CRP), and sIL-2R upon admission. Subjects were followed for 1 year. RESULTS: Low serum albumin, prealbumin, and hemoglobin and high sIL-2R and CRP predicted 1-year mortality on univariate analysis. When these predictors were included as covariates in a Cox regression model, only sIL-2R was a significant independent predictor of mortality (P = .043). Multiple linear regression with the above covariates revealed that only sIL-2R predicted time to death at (P = .003). CONCLUSIONS: High sIL-2R and CRP and low albumin, prealbumin, and hemoglobin predicted mortality using univariate analysis on a rehabilitation unit. However, with multivariate analysis, sIL-2R was the sole predictor of mortality. PMID- 9361664 TI - Acceptability of mobile mammography among community-dwelling older women. AB - OBJECTIVE: To test the acceptability of mobile mammography among community dwelling older women and to identify factors predictive of mobile mammography acceptance. DESIGN: Case series. SETTING: Twelve community meal sites sponsored by the City of Los Angeles Area on Aging. PARTICIPANTS: Two hundred fifty-five volunteers aged 60 to 84 years who attended community meal sites. INTERVENTION: On-site mammography offered to women who had not had a mammogram within the last year. MEASUREMENTS: Mammography acceptance rates, reasons for accepting or declining the mammogram, and breast cancer knowledge, beliefs, and intentions. MAIN RESULTS: One hundred seven of the 255 (42%) women were ineligible because they had received mammograms within the last year. Of the 148 women eligible, 57% accepted the mammograms and 43% declined; moreover, 20 of the 42 (48%) women who had not had a mammogram within the last 5 years or who never had a mammogram also accepted on-site mammography in the mobile van. Variables identified as predictive of mammogram acceptance included Asian American status, not being an HMO member, being married, a reported willingness to accept a screening mammogram if recommended by a physician, and previous mammogram screening history. CONCLUSION: Mobile mammography is acceptable to many older community-dwelling women. Although mobile mammography does not eliminate all barriers that inhibit a woman from receiving a mammogram, it may substantially increase screening for some groups. PMID- 9361665 TI - Geriatric rehabilitation: state of the art. AB - OBJECTIVES: To provide a clinically useful conceptual framework for the evaluation and treatment of disability in older persons, to review the rehabilitation of common conditions affecting function in older persons, and to discuss the effects of the ongoing changes in the healthcare system on geriatric rehabilitation. METHODS: MedLine search and review of relevant texts for information on (1) geriatric disability and its treatment, (2) recent high quality research, guidelines, and review articles relevant to the rehabilitation of conditions commonly causing geriatric disability, (3) effects of recent changes in the healthcare system on geriatric rehabilitation. RESULTS: Several pertinent models for geriatric disability were identified. These are explicated, along with information on the epidemiology of geriatric disability and its causes and relevant clinical applications. Rehabilitation is reviewed for musculoskeletal disorders, stroke and peripheral vascular disease, amputation, cardiopulmonary disorders, hip fracture, and deconditioning. Changes in the healthcare system appear to be affecting geriatric rehabilitation, especially the advent of managed care; relevant articles and opinions are reviewed, along with strategies to accommodate these changes. CONCLUSIONS: Our understanding of the causes of disability in the older population has improved significantly over the last decade. There has also been noteworthy progress in our knowledge about the effects of selected rehabilitation interventions, especially exercise-related interventions. However, the cost-effectiveness of many rehabilitative interventions remains unclear, particularly for differing patient groups across the continuum of care. More research will be needed to evaluate the effects of managed care on rehabilitation outcomes in older persons. PMID- 9361666 TI - Utility of ultrasound to assess risk of fracture. AB - Traditional assessments of bone properties have utilized densitometry techniques such as Dual Energy X-ray Absorptiometry (DXA). Recently, quantitative ultrasound (QUS) has been introduced as an alternative method of assessing bone properties. Advantages of QUS over X-ray techniques include low costs, portability, and nonionizing radiation. Proponents of QUS have claimed that this technology can provide information not only about the density but also about the structure and mechanical properties of bone. There are two major questions that need to be answered for those who seek to diagnose bone disorders with ultrasound: (1) what does quantitative ultrasound actually measure, and, even more importantly, (2) what is its clinical utility? In this review we will briefly examine the first question and will focus on the utility of ultrasound in clinical trials to discriminate between fractures and non-fractures and to predict the risk of fractures. PMID- 9361668 TI - DHEA--brass ring or red herring? PMID- 9361667 TI - DHEA: a biologist's perspective. PMID- 9361669 TI - Atrial fibrillation: understanding the serious consequences and learning about the causes. PMID- 9361670 TI - The relationship between gait changes and falls. PMID- 9361671 TI - Dementia does not prevent the restoration of safe gait after hip fracture. PMID- 9361672 TI - Geriatric assessment: can primary care fill the void? PMID- 9361673 TI - Dosing recommendations and prescribing patterns for depressed medically ill hospitalized older patients. PMID- 9361674 TI - High technology medical interventions: what do older people want? PMID- 9361675 TI - Lower serum cholesterol level and later decline in cognitive function in older people living in the community, Japan. PMID- 9361676 TI - Psychosocial and spiritual supports in coronary disease. PMID- 9361677 TI - Unilateral hydronephrosis, pyelonephritis, and bacteremia caused by a neglected vaginal ring pessary. PMID- 9361678 TI - Weight loss in Alzheimer's disease and resting energy expenditure (REE), a preliminary report. PMID- 9361679 TI - Growth hormone secretion and circulating insulin-like growth factor-I (IGF-I) and IGF binding protein-3 concentrations in children with sickle cell disease. AB - Impaired growth involving both height and weight accompanying sickle cell disease (SCD) poses diagnostic and therapeutic problems. We undertook this study to test the hypothesis that this impaired growth is associated with abnormalities of the growth hormone (GH)/insulin-like growth factor-I (IGF-I)/IGF binding protein-3 (IGFBP-3) axis in 21 children with SCD and that SCD is associated with GH resistance. Nine of 21 children with SCD had a defective GH response to both clonidine and glucagon provocation (peak < 10 micrograms/L); these children differed from the 12 others in having slower linear growth velocity (GV and GVSDS), lower circulating concentrations of IGF-I and IGFBP-3, and either partial or complete empty sellae in computed tomographic scans of the hypothalamic pituitary area. In this group of patients with SCD, it appears that defective GH secretion and consequent low IGF-I production are the major etiological factors causing the slow growth. The two groups with SCD did not differ significantly in dietary intake, body mass index (BMI), midarm circumferences, skinfold thickness, serum albumin concentration, or intestinal absorption of D-xylose. A single injection of GH produced a smaller increase in circulating IGF-I in children with SCD with or without defective GH secretion versus 10 age-matched children with idiopathic short stature (ISS) and 11 children with isolated GH deficiency (GHD), suggesting partial GH resistance in the SCD group. The presence of defective GH secretion, decreased IGF-I synthesis, and partial resistance to GH in short children with SCD suggests that treatment with IGF-I may be superior to GH therapy for improving growth. PMID- 9361680 TI - Effect of age on the response to parathyroid hormone. AB - Serum phosphate (PO4) levels and the tubular threshold for PO4 corrected for glomerular filtration (TP/GF) are age-dependent, being higher in children than in adults. We evaluated the effect of age on the response to infusion of parathyroid hormone(1-34) (PTH) in healthy children (n = 8) and adults (n = 12). In addition, six patients with pseudohypoparathyroidism (PHP) and two with PTH deficiency (hypoparathyroidism [HP]) were also studied. At baseline, TP/GF in normal subjects was inversely correlated with urinary cyclic adenosine monophosphate corrected for glomerular filtration (UcAMP/GF) (P < .0359). After PTH administration in the controls, UcAMP/GF was inversely correlated with TP/GF (P < .0007) and directly correlated with maximal fractional extraction of PO4 (FEP) (P < .0002). The slope of the regression of TP/GF (P < .0076) and FEP (P < .0034) with UcAMP/GF was steeper in children than in adults. Two HP patients had high PTH-stimulated UcAMP/GF levels, but stimulated TP/GF and FEP were not changed commensurate with levels that would expected from the normative data. In six patients with PHP, PTH-stimulated TP/GF was also correlated with peak UcAMP/GF (r = .96, P < .002). PHP patients could be distinguished from normal controls based on the combination of low peak FEP or high TP/GF together with low peak UcAMP/GF. Thus, in normal subjects, the phosphaturic response to PTH is correlated with the increase in urinary cAMP and is age-dependent, with a greater decrease of TP/GF in children than in adults. PMID- 9361681 TI - Amelioration of insulin resistance and hypertension in a fructose-fed rat model with fish oil supplementation. AB - In type II diabetic patients, one can detect several pathologic changes including insulin resistance and hypertension. Sprague-Dawley rats fed a fructose-rich diet (group F) exhibited these characteristic abnormalities within 2 weeks and were an excellent laboratory animal model for research on insulin action and development of hypertension. Since fish oils containing omega-3 fatty acids have a beneficial effect in preventing atherosclerotic diseases, we performed repeated experiments to test the effects of fish oil supplementation in group F rats. Compared with control rats on a normal diet (group C), group F consistently developed hypertriglyceridemia without elevated plasma free fatty acid (FFA), fasting hyperinsulinemia together with fasting hyperglycemia (insulin resistance syndrome), and systolic hypertension within 3 weeks. Insulin-stimulated glucose uptake and insulin binding of adipocytes were significantly reduced. Rats fed the same high-fructose diet but supplemented with fish oil (group O) had alleviation of all of these metabolic defects and a normalized insulin sensitivity and blood pressure. beta-Cell function as shown by plasma glucose and insulin responses to oral glucose remained intact in group F and group O. The plasma endothelin-1 (ET 1) level and ET-1 binding to adipocytes were not different among the three groups. Based on these results, we suggest that dietary high fructose induced hypertriglyceridemia and insulin resistance with normal islet function, and that the induced hypertension was not associated with plasma ET-1 abnormalities and was probably caused by other undefined pathologic changes that can be prevented by dietary omega-3 fatty acids. PMID- 9361682 TI - Inhibition of endosomal acidification in normal cells mimics the derangements of cellular insulin and insulin-receptor metabolism observed in non-insulin dependent diabetes mellitus. AB - Dissociation of the insulin-insulin receptor complex plays a crucial role in the processing of both insulin and the insulin receptor, and the acidification of endocytic vesicles may be the mechanism by which internalized insulin is dissociated from its receptor and properly sorted and processed. Internalized insulin-insulin receptor complexes are abnormally processed in cells from patients with non-insulin-dependent diabetes mellitus (NIDDM). Accordingly, to further investigate the mechanisms of the derangements observed in NIDDM cells, we examined the effects of the ionophore monensin, which inhibits endosomal acidification, on the cellular processing of insulin and insulin receptor in monocytes from control subjects (n = 12) and NIDDM patients (n = 14). This study confirms that monocytes from NIDDM patients, compared with cells from normal controls, had reduced binding (P < .01), internalization (P < .01), and degradation (P < .01) of insulin. In addition, the release of intracellular radioactivity was slower (P < .01), and recycling of the insulin receptor was inhibited (P < .01). Moreover, these defects were associated with a significant (P < .01) decrease of dissociation of the internalized insulin-insulin receptor complex. In cells from normal controls, incubation with monensin decreased insulin binding (P < .01), but not insulin internalization. High-performance liquid chromatography (HPLC) analysis of intracellular radioactivity showed that after monensin intracellular intact insulin significantly increased (P < .01), thus suggesting a decrease of intracellular insulin degradation. Moreover, insulin receptor recycling was completely disrupted. All of these derangements were associated with a significant decrease (P < .01) of dissociation of insulin insulin receptor complexes. On the contrary, in diabetic monocytes, monensin had no significant additional effect on NIDDM-linked alterations. Comparison of the results obtained in cells from NIDDM patients to those found in monensin-treated normal cells demonstrates that NIDDM and monensin gave rise to a superimposable impairment of dissociation of the intracellular insulin-insulin receptor complex, associated with similar abnormal sorting and processing of insulin and its receptor. The only defect present in NIDDM cells but not in monensin-treated cells is the decrease of insulin internalization, which thus seems independent of the action of monensin on the processing of internalized insulin-insulin receptor complex. These results suggest that the impairment of dissociation of the insulin insulin receptor complex may play a crucial role in the subsequent altered processing of insulin and insulin receptor. Moreover, they raise the question as to a possible similar alteration of the same intracellular mechanism by NIDDM and monensin, and point out that the derangements found in cells from NIDDM patients could be localized within the endosomal apparatus and consist mainly of a defective acidification of its interior. PMID- 9361683 TI - Handgrip strength and insulin levels: cross-sectional and prospective associations in the Normative Aging Study. AB - Hyperinsulinemia is associated with insulin resistance and with the development of diabetes, hypertension, and coronary heart disease. Physical activity appears to be negatively associated with insulin resistance, although the mechanism is unclear. The relationship between physical activity and insulin resistance could be mediated, in part, by direct effects on skeletal muscle, a significant site for insulin-mediated glucose disposal. This report examines the relationship between skeletal muscle strength (as measured by handgrip dynamometry) and fasting insulin levels in a cohort of men in the ongoing Normative Aging Study (NAS). Handgrip strength was negatively associated (P = .013) with logarithmic (log) fasting insulin in cross-sectional data from 655 subjects after adjustment for potential confounders including age, body mass index (BMI), ratio of abdominal girth to hip breadth (AG/HB), usual physical activity level, and alcohol intake in a multiple regression model. In data collected prospectively among 1,195 subjects, handgrip strength measured at study entry was negatively predictive of log fasting insulin (P = .017) measured 22.9 +/- 2.6 years later, after adjustment for age, BMI, and AG/HB at study entry in a multiple linear regression model. A cross-sectional association was confirmed in an analysis of prospective data on the relationship between handgrip strength and fasting insulin levels. The findings suggest that skeletal muscle weakness may precede and predict the development of insulin resistance, and raise the intriguing possibility of some common cause in skeletal muscle pathophysiology. PMID- 9361684 TI - Insulin inhibition of 5' adenosine monophosphate-activated protein kinase in the heart results in activation of acetyl coenzyme A carboxylase and inhibition of fatty acid oxidation. AB - Acetyl coenzyme A (CoA) carboxylase (ACC) is an important regulator of fatty acid oxidation in the heart, since it produces malonyl CoA, a potent inhibitor of mitochondrial fatty acid uptake. Under conditions of metabolic stress, 5'adenosine monophosphate-activated protein kinase (AMPK), which is highly expressed in cardiac muscle, can phosphorylate and decrease ACC activity. In this study, we determined if fatty acid oxidation in the heart could be regulated by insulin, due to alterations in AMPK regulation of ACC activity. Isolated working rat hearts were perfused with Krebs-Henseleit solution containing 11 mmol/L glucose, 0.4 mmol/L [9,10(-3)H]palmitate, and either 100 microU/mL insulin or 1,000 microU/mL insulin. Increasing insulin concentration resulted in a decrease in fatty acid oxidation rates (P < .05), a decrease in AMPK activity (P < .05), and an increase in ACC activity (P < .05) compared with the low-insulin group. A negative correlation was observed between AMPK and ACC activity (r = -.76). We conclude that insulin, acting through inhibition of AMPK and stimulation of ACC, is capable of inhibiting myocardial fatty acid oxidation. PMID- 9361685 TI - Insulin resistance is not a major determinant of low-density lipoprotein particle size. AB - The relationship between low-density lipoprotein (LDL) peak particle diameter and insulin sensitivity, very-low-density lipoprotein (VLDL) + intermediate-density lipoprotein (LDL) triglyceride, cholesterol, and apoprotein B, postprandial lipemia, and LDL + high-density lipoprotein (HDL) triglyceride was assessed. The subjects were 101 healthy males aged 15 to 45 years. Sixty-one subjects (60.4%) were offspring of a parent with coronary artery disease before age 60, and 40 subjects (39.6%) had no parental history of coronary artery disease. LDL peak particle diameter was measured following polyacrylamide gradient gel electrophoresis. An insulin sensitivity index (Si) was determined from a frequently sampled intravenous glucose tolerance test using a minimal modeling method. A fat tolerance test was performed with a test meal containing 70 g/m2 fat, with triglyceride concentrations measured hourly for 12 hours. LDL peak particle diameter was significantly correlated with body mass index (BMI) (r = .282, P < .01), waist to hip ratio (r = -.291, P < .01), fasting triglyceride (logarithmically [log] transformed) (r = -.566, P < .001), area under the postprandial triglyceride curve (log transformed) (r = -.562, P < .001), VLDL + IDL triglyceride (log transformed) (r = -.462, P < .001), VLDL + IDL cholesterol (log transformed) (r = -.477, P < .001), VLDL + IDL apoprotein B (log transformed) (r = -.321, P < .001), LDL + HDL triglyceride (log transformed) (r = .583, P < .001), and HDL cholesterol (r = .347, P < .001), but there was no significant correlation with Si. Using stepwise regression analysis, LDL + HDL triglyceride showed the strongest relationship to LDL peak particle diameter, accounting for 34% of the variation in size. Si was not an independent predictor of LDL particle size. In conclusion, insulin sensitivity appears to have little influence on LDL particle size. The importance of LDL + HDL triglyceride should be considered a preliminary finding warranting verification in this and other populations. PMID- 9361686 TI - Insulin resistance and advancing age: what role for dehydroepiandrosterone sulfate? AB - The relationship between insulin resistance and aging is still debated. This study aims to investigate the role that age-related differences in plasma dehydroepiandrosterone sulfate (DHEAS) concentration may have on insulin action. For this reason, 75 subjects (42 men and 33 women) with a wide age range (21 to 106 years) were studied. In all subjects, plasma DHEAS and total testosterone concentrations were measured and a euglycemic clamp was used, but substrate oxidation was not determined in centenarians (n = 15). Plasma DHEAS correlated with age (r = -.77, P < .001) and whole-body glucose disposal (WBGD) (r = .57, P < .001). After controlling for age, sex, body fat, and waist to hip ratio (WHR), the association between plasma DHEAS and WBGD was still observed (r = .31, P < .005). Comparing subjects at the third tertile versus those at the first and second tertiles of plasma age-adjusted DHEAS concentration, the former group showed a weaker association between WBGD and age (r = -.38, P < .05) than the latter group (r = -.43, P < .002). The difference between the two regression lines was also significant (P < .03). After controlling for sex, body fat, and WHR, the association between plasma DHEAS and WBGD was dependent on the age of the subjects, being strong in adults (n = 30, age < 50 years, r = .69, P < .001), weak in old subjects (n = 30, age 51 to 99 years, r = .23, P < .05), and absent in centenarians (r = -.05, P < .88). With the subjects divided by sex throughout the different age groups, the univariate association between plasma DHEAS and WBGD was present in females (r = .43, P < .01) but not in males (r = .17, P < .32). Plasma total testosterone and insulin-like growth factor-1 (IGF-1) concentrations declined with advancing age and were significantly correlated with DHEAS and WBGD. In a multivariate analysis with WBGD as the dependent variable, a model including age, sex, body fat, WHR, DHEAS, total testosterone, and IGF-1 explained 66% of WBGD variability, with DHEAS significantly and independently associated with WBGD (P < .004). In conclusion, the negative relationship between advancing age and insulin action seems related to plasma DHEAS concentration. Differences in plasma total testosterone and IGF-1 concentrations may provide a further contribution to the relationship between DHEAS and WBGD. PMID- 9361687 TI - Lower androgenicity is associated with higher plasma levels of prothrombotic factors irrespective of age, obesity, body fat distribution, and related metabolic parameters in men. AB - The purpose of this study was to examine the relationships between androgenic status and plasma levels of both prothrombotic and antithrombotic factors in men, irrespective of obesity, body fat distribution, and metabolic parameters. Sixty four apparently healthy men, 40 with a body mass index (BMI) greater than 25 kg/m2 (overweight and obese [OO]) and 24 non-obese controls with a BMI less than 25, were selected and evaluated for (1) plasma concentrations of plasminogen activator inhibitor-1 (PAI-1) antigen, PAI-1 activity, fibrinogen, von Willebrand factor (vWF) antigen, vWF activity, and factor VII (FVII) as the prothrombotic factors; (2) plasma levels of tissue plasminogen activator (TPA) antigen, protein C, and antithrombin III as the antithrombotic factors; (3) fasting plasma concentrations of insulin and glucose and the lipid pattern (triglycerides [TG] and total and high-density lipoprotein [HDL] cholesterol) as the metabolic parameters; and (4) free testosterone (FT), dehydroepiandrosterone sulfate (DHEAS), and sex hormone-binding globulin (SHBG) serum levels as the parameters of androgenicity. Body fat distribution was evaluated by the waist to hip ratio (WHR). In OO and non-obese subjects taken together, plasma levels of PAI-1 antigen, fibrinogen, and FVII were inversely associated with FT (r = .255, P < .05, r = -3.14, P < .05, and r = -.278, P < .05, respectively), and the negative relationships of both fibrinogen and FVII with FT were maintained after stepwise multiple regression analysis. Plasma concentrations of PAI-1 antigen and PAI-1 activity were also negatively correlated with SHBG (r = -.315, P < .05 and r = .362, P < .01, respectively), and these associations held irrespective of the other parameters investigated. None of the antithrombotic and fibrinolytic factors were independently related to serum androgen levels. Subjects with a BMI higher than 25 kg/m2 had higher plasma concentrations of PAI-1 antigen, PAI-1 activity, and fibrinogen as compared with non-obese controls (P < .001, P < .001, and P < .01, respectively). In addition, in OO and control subjects as a whole, multiple stepwise regression analysis showed that the associations of BMI with PAI-1 activity, fibrinogen, vWF antigen, and vWF activity were independent of any other metabolic and hormonal parameters. Plasma concentrations of PAI-1 antigen, PAI-1 activity, and fibrinogen were also directly correlated with WHR in all subjects taken together, irrespective of the other parameters investigated. Evaluation of antithrombotic factors showed that OO subjects had higher TPA plasma concentrations than non-obese controls (P < .001), whereas protein C and antithrombin III did not differ in the two groups. TPA was also directly correlated with BMI (r = .415, P < .001) and WHR (r = .393, P < .001) in all subjects. The results of this study indicate that (1) men with lower FT serum levels have higher fibrinogen and FVII plasma concentrations, and those with lower SHBG serum levels also have higher levels of PAI-1 antigen and activity; (2) irrespective of other factors, obesity per se may account for higher concentrations of PAI-1, fibrinogen, and vWF; (3) plasma levels of PAI-1 (antigen and activity) and fibrinogen correlate independently with WHR; and (4) among the investigated antithrombotic factors (TPA antigen, protein C, antithrombin III), only TPA antigen plasma concentrations are higher in men with abdominal obesity. Thus, because of the increase in several prothrombotic factors, men with central obesity, particularly those with lower androgenicity, seem to be at greater risk for coronary heart disease (CHD). Apparently, this risk is not counteracted by a parallel increase in plasma concentrations of antithrombotic factors. PMID- 9361688 TI - Daily energy requirements in heart failure patients. AB - Diminished body cell mass in heart failure patients contributes to poor prognosis and decreased quality of life. The level of daily energy intake needed to maintain body cell mass and optimal physiological function in heart failure patients is unknown. Thus, we examined daily energy expenditure in free-living heart failure patients to estimate daily energy requirements. Daily energy expenditure (doubly labeled water) and its components (resting and physical activity energy expenditures) were measured in 26 heart failure patients (25 men and one woman aged 69 +/- 7 years) and 50 healthy controls (48 men and two women aged 69 +/- 6 years). Resting energy expenditure was measured by indirect calorimetry; physical activity energy expenditure from the difference between daily and resting energy expenditure; body composition by dual-energy x-ray absorptiometry; leisure time physical activity from a questionnaire; and peak oxygen consumption ([peak VO2] n = 16 heart failure patients) from a treadmill test to exhaustion. Plasma markers of nutritional status were also considered. Daily energy expenditure was 17% lower (2,110 +/- 500 v 2,543 +/- 449 kcal/d) and physical activity energy expenditure 54% lower (333 +/- 345 v 728 +/- 374 kcal/d) in heart failure patients compared with healthy controls. Daily energy expenditure was related to physical activity energy expenditure (r = .79, P < .01), resting energy expenditure (r = .63, P < .01), leisure time physical activity (r = .63, P < .01), and peak VO2 (r = .58, P < .01) in heart failure patients. Stepwise regression analysis showed that daily energy requirements in heart failure patients were best estimated by a combination of resting energy expenditure and reported leisure time physical activity (total R2 = 61%; standard error of the estimate, +/- 333 kcal/d). Daily energy requirements predicted from equations derived in healthy elderly were inaccurate when applied to heart failure patients, deviating -10% to +30% from measured daily energy expenditure. We conclude that despite low levels of activity, markers of physical activity predicted daily energy needs in heart failure patients. We provide a new equation to estimate energy needs in free-living heart failure patients based on measurements of daily energy expenditure. PMID- 9361689 TI - Postprandial hemorrheology and apolipoprotein B metabolism in patients with familial hypertriglyceridemia. AB - Impaired postprandial lipoprotein metabolism has been found to be related to the extent of coronary artery disease. Moreover, since dyslipoproteinemias are associated with impaired hemorrheology, we investigated the effect of postprandial hypertriglyceridemia on hemorrheological parameters before and after triglyceride-lowering therapy. Triglyceride-rich lipoproteins (TRLs) separated by ultracentrifugation (d < 1.006 g/dL) and chylomicrons and chylomicron remnants (quantified by apolipoprotein [apo] B-48 determination) were determined after a fat load in 10 patients with familial hypertriglyceridemia before and after therapy with gemfibrozil (900 mg daily). Lipid and hemorrheological parameters (plasma and whole-blood viscosity [PV and BV], red cell aggregation [RCA], hematocrit, and fibrinogen) were determined at baseline and every hour up to 6 hours postprandially. Fasting total triglycerides and TRL triglycerides significantly decreased with gemfibrozil therapy (P < .01). Total triglycerides postprandially increased from 9.53 +/- 1.72 to 14.47 +/- 2.07 mmol/L (TRL triglycerides by 61%) before therapy (P < .05) and from 4.61 +/- 1.28 to 7.17 +/- 0.99 mmol/L (TRL triglycerides by 57%) after therapy (P < .05). The postprandial TRL apo B increase was reduced with gemfibrozil (from 11.6 +/- 2.8 to 20.7 +/- 5.0 mg/dL with therapy v 19.0 +/- 7.6 to 33.0 +/- 12.5 mg/dL before therapy, P < .05, respectively) with a proportionally greater increase in apo B-48 (119% and 169%, respectively) compared with apo B-100 (64% and 64%, respectively). Fasting RCA was improved with lipid-lowering therapy (P < .05), but PV, BV, RCA, and fibrinogen did not show any statistically significant postprandial changes either before or after lipid-lowering therapy. In summary, we did not find any statistically significant changes in hemorrheological parameters, despite a strong postprandial increase of triglycerides. In particular, these findings were independent of fasting triglyceride levels. We conclude that triglyceride lowering therapy by gemfibrozil had no substantial beneficial effects with respect to hemorrheology in patients with familial hypertriglyceridemia. PMID- 9361691 TI - Lipolysis in elderly postmenopausal women. AB - The rate of fat oxidation at rest decreases with age in women. The mechanisms for this decrease are not clear. Theoretically, a decrease in the availability of fatty acids could explain the decline in fat oxidation. In consequence, the in vivo rate of production of fatty acids as a proxy for lipolysis was measured in 21 healthy women. Eleven of the volunteers were elderly (> 65 years) and 10 were young (< 24 years), and all were characterized for body composition. The nonadjusted rate of delivery of fatty acids into the systemic circulation was similar among elderly and young individuals (609 +/- 80.3 v 597 +/- 69.9 mumol/min, respectively, P > .1). When lipolysis was adjusted for the differences in fat-free mass using analysis of covariance (ANCOVA), rates were slightly increased in the elderly group (626 +/- 80 mumol/min) and decreased in the young group (578 +/- 84 mumol/min), but remained nonstatistically significant. It is concluded that mechanisms other than lipolysis must explain the decrease of fat oxidation in aging women, i.e., a decrease in the capacity of muscle to oxidize fat and/or a decrease in its capacity for transport of long-chain fatty acids. PMID- 9361690 TI - Effects of cholinergic blockade on nocturnal thyrotropin and growth hormone (GH) secretion in type I diabetes mellitus: further evidence supporting somatostatin's involvement in GH suppression. AB - To investigate the influence of cholinergic pathways on somatostatin (SS) tone in type I diabetes mellitus, we studied the effect of the muscarinic receptor antagonist pirenzepine ([PZP] 100 mg orally) on spontaneous nocturnal growth hormone (GH) and thyrotropin (TSH) secretion and on their response to GH releasing hormone (GHRH) in the morning in a group of nine insulin-dependent diabetic patients with poor diabetic control. When the nocturnal period was divided into two phases (11:00 PM to 2:30 AM and 3:00 AM to 6:00 AM), both GH and TSH mean concentrations during the first phase were higher than those seen in the second half of the night following placebo administration (GH, 13.4 +/- 1.1 v 4.15 +/- 0.9 ng/mL, P < .001; TSH, 1.9 +/- 0.21 v 1.57 +/- 0.1 microU/mL, P < .05). Pretreatment with PZP induced a significant reduction of GH secretion (3.17 +/- 1.1 v 13.4 +/- 1.1 ng/mL, P < .001) and TSH secretion (1.61 +/- 0.21 microU/mL, P < .05) in the first phase of the night, accounting for a 64% and 11% reduction in the GH and TSH nocturnal peak, respectively. PZP reduced the GH response to GHRH in the morning (17.9 +/- 2.7 v 36.7 +/- 6.3 ng/mL, P < .05), but did not induce any change in TSH values at that time. A positive relationship (r = .73, P < .01) was observed between the percent reduction of the GH response to GHRH and that of the nocturnal GH peak following PZP administration. PZP caused a significant reduction in glucose levels during the second phase of the night (6.4 +/- 0.92 v 9.81 +/- 0.85 mmol/L, P < .05). These results demonstrate that administration of PZP reduces GH and TSH secretion, providing further support for the involvement of SS in the inhibition of GH secretion induced by cholinergic antagonists in type I diabetics. The inhibitory effect of PZP on GHRH-induced GH secretion may help to predict nocturnal GH behavior following administration of the drug. PMID- 9361693 TI - Total energy expenditure in human immunodeficiency virus-infected men and healthy controls. AB - Total daily energy expenditure (TEE) has been reported to be slightly decreased in weight-stable acquired immune deficiency syndrome (AIDS) patients. This conclusion is based on a comparison of TEE measurements to the data reported by others. We measured TEE in nine weight-stable human immunodeficiency virus (HIV) infected homosexual men (Centers for Disease Control [CDC]-II to -IV) without active opportunistic disease and nine age-, sex-, and height-matched healthy controls using the doubly labeled water technique for 2 weeks, and resting energy expenditure (REE) using the ventilated-hood technique. TEE in HIV-Infected patients was not significantly different from that in healthy controls (221 +/- 12.5 and 210 +/- 9 kJ.kg lean body mass [LBM]-1.d-1, respectively, NS). REE was approximately 10% higher in HIV patients than in healthy controls (134 +/- 4 and 125 +/- 4 kJ.kg LBM-1.d-1, respectively, P = .02). The energy spent in relation to physical activity was not different between HIV-Infected patients and the controls (66 +/- 10 and 64 +/- 5 kJ.kg LBM-1.d-1, respectively, NS). In conclusion, REE is increased by about 10% in weight-stable HIV-infected men without active opportunistic disease. TEE and the energy spent during physical activity are not different in this group of patients versus healthy controls. This is in contrast to the previously reported decrease of TEE in weight-losing AIDS patients. Therefore, the energy requirements of stable HIV-infected patients are not decreased compared with those of healthy subjects. PMID- 9361692 TI - Na+/Li+ and Na+/H+ countertransport activity in hypertensive non-insulin dependent diabetic patients: role of insulin resistance and antihypertensive treatment. AB - We measured erythrocyte Na+/Li+ and Na+/H+ countertransport (CT) activity (millimoles per liter per cell per hour) in 10 healthy control subjects (age, 38 +/- 4 years; body mass index, 25 +/- 1 kg/m2) and in 25 hypertensive patients with non-insulin-dependent diabetes mellitus ([NIDDM] age, 49 +/- 3 years; body mass index, 29 +/- 1 kg/m2; fasting plasma glucose, 157 +/- 12 mg/dL) 4 weeks after discontinuation of previous antihypertensive treatment. Na+/Li+ CT was significantly increased in hypertensive NIDDM patients compared with controls (0.56 +/- 0.04 v 0.30 +/- 0.03, P < .01), whereas Na+/H+ CT was similar to control levels (21 +/- 1 v 20 +/- 2). A positive correlation was found between Na+/Li+ CT and the severity of insulin resistance (r = .69, P < .01), mean arterial pressure ([MAP] r = .64, P < .01), plasma triglyceride concentration (r = .46, P < .05), and plasma total cholesterol (r = .41, P < .05). An inverse correlation was found between Na+/Li+ CT activity and plasma insulin concentration (r = -.47, P < .05). No relationship was observed between Na+/Li+ CT activity and either creatinine clearance or proteinuria. Stepwise multiple regression analysis for all metabolic variables and blood pressure showed that only the severity of insulin resistance was positively correlated with increased Na+/Li+ CT activity. Na+/H+ and Na+/Li+ CT activity were not altered by 3 hours of euglycemic physiologic hyperinsulinemia (84 +/- 3 microU/mL). Hypertensive NIDDM subjects were treated for 3 months with captopril, nifedipine, or doxazosin. After captopril, a reduction of Na+/H+ CT was observed (22 +/- 4 v 13 +/- 2, P < .05); Na+/Li+ CT decreased after doxazosin (0.56 +/- 0.06 v 0.45 +/- 0.05, P < .05) and nifedipine (0.52 +/- 0.06 v 0.42 +/- 0.05, P < .05). In conclusion, in hypertensive NIDDM subjects, (1) Na+/Li+ CT is increased and is correlated with the level of insulin resistance and the MAP; (2) acute physiologic hyperinsulinemia does not affect Na+/Li+ or Na+/H+ CT activity; and (3) Na+/H+ CT activity is reduced by captopril, and Na+/Li+ CT is decreased by doxazosin and nifedipine. PMID- 9361694 TI - Sympathetic drive to liver and nonhepatic splanchnic tissue during prolonged exercise is increased in diabetes. AB - This study was conducted to assess whether nonhepatic splanchnic (NHS) and hepatic tissues contribute to the increase in circulating norepinephrine during prolonged exercise, and to determine whether such a response is exaggerated during exercise in the poorly controlled diabetic when the arterial norepinephrine response is excessive. Chronically catheterized (carotid artery, portal vein, and hepatic vein) and instrumented (Doppler flow probes on hepatic artery and portal vein) normal (n = 6) and alloxan-diabetic (n = 5) dogs were studied during rest (30 minutes) and moderate treadmill exercise (150 minutes). Basal plasma glucose of diabetic dogs was threefold that of control dogs. Since epinephrine is not released by splanchnic tissues, NHS and hepatic epinephrine fractional extraction (FX) can be accurately measured. Because epinephrine FX = norepinephrine FX, norepinephrine spillover can be calculated. NHS and hepatic epinephrine FX remained stable during rest and exercise in both control and diabetic dogs. Although basal NHS norepinephrine spillover was not different between the two groups, basal hepatic norepinephrine spillover was lower in the controls (1.1 +/- 0.3 ng/kg . min) compared with the diabetics (3.6 +/- 1.1 ng/kg . min). Although NHS norepinephrine spillover increased with exercise in the normal dog (3.1 +/- 0.6 ng/kg . min at t = 150 minutes), there was no increase in hepatic norepinephrine spillover (1.1 +/- 0.3 ng/kg . min at t = 150 minutes). In contrast, NHS (8.8 +/- 1.6 ng/kg . min at t = 150 minutes) and hepatic (6.9 +/- 1.8 ng/kg . min at t = 150 minutes) norepinephrine spillover were both markedly increased in the diabetic dog to rates approximately threefold and sixfold higher than in the normal dog. These data show that an increase in NHS but not hepatic norepinephrine spillover is a component of the normal response to prolonged exercise. The exaggerated increase in arterial norepinephrine during exercise in the diabetic state is due, in part, to both increased sympathetic drive to the gut and liver. This increase in sympathetic drive to the splanchnic bed may contribute to the deleterious effects of exercise in poorly controlled diabetes. PMID- 9361695 TI - Fructose-3-phosphate production and polyol pathway metabolism in diabetic rat hearts. AB - Previous studies have suggested that polyol-pathway and nonenzymatic glycation may be involved in the development of cardiac myopathy, a well-known manifestation of diabetes. Although the exact etiology of this complication is not fully understood, it is likely to be multifactorial. In this study, we investigated the metabolic consequences of diabetes and the effect of aldose reductase inhibitor (ARI) treatment on cardiac tissues of Sprague-Dawley rats. Perchloric acid (PCA) extracts of hearts from the animals were examined using 31P nuclear magnetic resonance (NMR), gas chromatography/mass spectrometry (GC/MS), and high-performance liquid chromatography (HPLC). In 31P-NMR spectra of diabetic animals, a peak resonating at the chemical shift of 5.8 ppm with a coupling constant of 10 Hz was identified as fructose-3-phosphate (F3P). Undetectable in controls (< approximately 20 nmol/g), this metabolite was present at a concentration of 81.3 +/- 16.3 nmol/g wet weight (n = 4) in diabetic rat hearts. GC/MS analysis of these extracts from diabetics also identified a decomposition product of F3P, 3-deoxyglucosone (3DG), at a concentration of 9.4 +/- 3.5 nmol/g (n = 3), compared with 0.98 +/- 0.43 nmol/g (n = 3) in controls. No evidence was found for the expected detoxification products of 3-DG, 3-deoxyfructose and 2 keto 3-deoxygluconate. Concomitant with the elevation of F3P and 3DG, fructose and sorbitol levels were also elevated in diabetic animals. Surprisingly, ARI treatment was found to have no effect on the levels of these metabolites. These data suggest that either the heart may be unique in its production of fructose or it may not readily transport the ARI sorbinil. Production of the potent glycating agents F3P and 3DG in diabetics suggests that these compounds may be contributing factors in the glycation of cardiac proteins in the diabetic rat heart. PMID- 9361696 TI - Effect of muscular exercise on the concentration of uridine and purine bases in plasma--adenosine triphosphate consumption-induced pyrimidine degradation. AB - To identify whether muscular exercise increases the plasma concentration of uridine and of purine bases, the effect of rigorous muscular exercise was determined in five healthy men with a bicycle ergometer. Twenty-five-minute muscular exercise at 65% maximum O2 consumption increased the concentration of uridine, purine bases, and inorganicphosphate in plasma and of NH3 and lactic acid in blood. These results suggest that exercise-induced excessive adenosine triphosphate (ATP) consumption enhanced not only purine degradation but also pyrimidine degradation (uridine triphosphate [UTP]-->uridine diphosphate [UDP]- >uridine monophosphate [UMP]-->uridine) in exercising muscles. PMID- 9361697 TI - Modulation of chronic excessive interleukin-6 production in multiple myeloma does not affect thyroid hormone concentrations. AB - Interleukin-6 (IL6) is believed to be involved in alterations of thyroid hormone metabolism in acute nonthyroidal illness. To evaluate the effects of IL6 on thyroid hormone metabolism in a chronic IL6-mediated disease, we measured thyroid hormone concentrations in multiple myeloma patients treated with intravenous anti IL6 chimeric monoclonal antibodies ([cMabs] Kd = 6.25 x 10(-12) mol/L). Twelve patients were studied, receiving at least one complete treatment cycle of 14 days (daily dose: 5 mg, n = 3; 10 mg, n = 3; 20 mg, n = 3; and 40 mg, n = 3). Eight of them also completed a second treatment cycle of 14 days. Thyroid hormone concentrations were measured before, during, and after treatment with the anti IL6 cMab. Even in the group with the lowest dosage, IL6 activity measured by the B9 bioassay was blocked completely. Compared with the reference ranges, 10 of 12 patients had one or more abnormal pretreatment values for thyroid hormone concentrations. Thyroid autoantibodies were negative in all patients. There was no correlation between thyroid hormone concentrations and IL6 levels, although plasma IL6 levels were increased in all but one subject. Moreover, neutralization of free IL6 by the anti-IL6 cMab did not affect thyroid hormone concentrations, although IL6-dependent C-reactive protein (CRP) levels decreased to undetectable levels in 11 of 12 patients. Two patients developed infectious complications resulting in increased free IL6 and CRP levels and in profound alterations of thyroid hormone levels consistent with an acute euthyroid sick syndrome. We conclude that IL6 is not a major determinant of thyroid hormone abnormalities in a chronic disease like multiple myeloma, but IL6 may be involved in thyroid hormone metabolism in acute diseases (probably in combination with other factors). PMID- 9361699 TI - Glucose production and gluconeogenesis in postabsorptive and starved normal and streptozotocin-diabetic rats. AB - Using a 3-hour primed-continuous infusion of [3-3H]glucose and [2-13C]glycerol, we measured glucose production, gluconeogenesis from glycerol, and total gluconeogenesis (using mass isotopomer distribution analysis [MIDA] of glucose) in postabsorptive and starved normal and streptozotocin-diabetic rats. In normal rats, 48 hours of starvation increased (P < .01) the percent contribution of both gluconeogenesis from glycerol (from 14.4% +/- 1.8% to 25.5% +/- 4.0%) and total gluconeogenesis (from 52.2% +/- 3.9% to 89.8% +/- 1.3%) to glucose production, but the absolute gluconeogenic fluxes were not modified, since glucose production decreased. Diabetic rats showed increased glucose production in the postabsorptive state; this decreased with starvation and was comparable to the of controls after 48 hours of starvation. Gluconeogenesis was increased in postabsorptive diabetic rats (69.0% +/- 1.3%, P < .05 v controls). Surprisingly, this contribution of gluconeogenesis to glucose production was not found to be increased in 24-hour starved diabetic rats (64.4% +/- 2.4%). These rats had significant liver glycogen stores, but gluconeogenesis was also low (42.8% +/- 2.1%) in 48-hour starved diabetic rats deprived of glycogen stores. Moreover, in 24-hour starved diabetic rats infused with [3-13C]lactate, gluconeogenesis was 100% when determined by comparing circulating glucose and liver pyruvate enrichment, but only 47% +/- 3% when calculated from the MIDA of glucose. Therefore, MIDA is not a valid method to measure gluconeogenesis in starved diabetic rats. This was not explained by differences in the labeling of liver and kidney triose phosphates: functional nephrectomy of starved diabetic rats decreased glucose production, but gluconeogenesis calculated by the MIDA method was only 48% +/- 3.3%. We conclude that (1) diabetic rats have increased glucose production and gluconeogenesis in the postabsorptive state; (2) starvation decreases glucose production and increases the contribution of gluconeogenesis, but MIDA is not an appropriate method in this situation; and (3) the kidneys contribute to glucose production in starved diabetic rats. PMID- 9361698 TI - Exercise in transgenic mice overexpressing GLUT4 glucose transporters: effects on substrate metabolism and glycogen regulation. AB - We assessed the effects of GLUT4 glucose transporter expression on substrate metabolism and glycogen regulation during exercise. Transgenic mice overexpressing human (h)GLUT4 in muscle and fat (TG) and their wild-type littermates (WT) were studied by indirect calorimetry at rest and during acute treadmill exercise (30 minutes) and recovery (30 minutes). The rate of carbon dioxide production (VCO2) increased to a greater degree in TG during exercise, whereas resting VCO2, resting oxygen production (VO2), and exercise-induced increments in VO2 were similar in TG and WT. As a result, the respiratory quotient (RQ) was increased by .03 to .05 in TG during exercise, due to greater consumption of carbohydrate (up to approximately 64% more) and less consumption of lipid (up to approximately 40% less) compared with WT, without differences in overall energy expenditure. These differences in substrate metabolism were observed despite relative hypoglycemia and elevated free fatty acids (FFAs) in TG that persisted throughout resting, exercise, and recovery periods. To further assess substrate availability, glycogen content and glycogen synthase activity were measured in skeletal muscle and liver. At rest, muscle glycogen content was 50% higher and glycogen synthase I was 40% lower in TG compared with WT. During exercise and recovery, muscle glycogen was more profoundly depleted in TG than in WT, and glycogen synthase I increased to levels observed in WT, with no change in total glycogen synthase. In the liver, glycogen content and total glycogen synthase were similar in TG and WT under resting conditions, while glycogen synthase I was reduced by 48%. Exercise and recovery induced a more profound depletion of liver glycogen (76% v 30%) and greater increments in both I-form and total glycogen synthase in TG. In conclusion, (1) TG overexpressing GLUT4 exhibit greater muscle glycogen content at rest than WT; (2) during exercise, TG metabolize more carbohydrate, made possible by increased glycogenolysis in muscle and liver, and this predominates as a fuel source despite hypoglycemia and increased availability of FFA; (3) increased carbohydrate metabolism is linked to a decrease in lipid metabolism such that there is no change in overall energy expenditure; and (4) glycogen synthase I activity is inversely proportional to tissue glycogen content despite differences in circulating glucose, insulin, and FFA concentrations, indicating that glycogen content has an overriding regulatory influence on glycogen synthase. PMID- 9361700 TI - Comparison of arterialized venous sampling from the hand and foot in the assessment of in vivo glucose metabolism. AB - To determine whether arterialized venous blood obtained from a foot vein could be substituted for arterialized venous blood obtained from a hand vein during studies using the glucose clamp technique, we simultaneously measured glucose concentrations and PO2 in blood samples obtained from the heated hands and feet of five normal volunteers during the euglycemic and hyperglycemic steps of a hyperinsulinemic clamp. Plasma glucose concentrations were found to be virtually identical in arterialized venous blood drawn from the hand and the foot under both euglycemic and hyperglycemic conditions. The correlation between these values was significant (R2 = .99, P < .001). PO2 measurements in blood drawn from the heated hand or foot were not statistically different. We conclude that the glucose concentration measured in arterialized venous blood drawn from the foot is equivalent to the concentration in arterialized venous blood drawn from the hand. These observations will allow investigators to study in vivo glucose metabolism in individuals with poor venous access in the upper extremities and to use protocols that make the arms of the subject inaccessible for blood sampling during the study. PMID- 9361701 TI - [NMDA antagonists--current aspects of the pathogenesis and therapy of Parkinson disease]. PMID- 9361702 TI - [20 years of the "strait-shaft." Possible uses--long-term studies--further improvements]. PMID- 9361703 TI - [Panic and depression: early diagnosis of patients at risk, early treatment with an SSRI (Selective Serotonin Reuptake Inhibitor)]. PMID- 9361704 TI - Long-term habituation (LTH) in the crab Chasmagnathus: a model for behavioral and mechanistic studies of memory. AB - A decade of studies on long-term habituation (LTH) in the crab Chasmagnathus is reviewed. Upon sudden presentation of a passing object overhead, the crab reacts with an escape response that habituates promptly and for at least five days. LTH proved to be an instance of associative memory and showed context, stimulus frequency and circadian phase specificity. A strong training protocol (STP) (> or = 15 trials, intertrial interval (ITI) of 171 s) invariably yielded LTH, while a weak training protocol (WTP) (< or = 10 trials, ITI = 171 s) invariably failed. STP was used with a presumably amnestic agent and WTP with a presumably hypermnestic agent. Remarkably, systemic administration of low doses was effective, which is likely to be due to the lack of an endothelial blood-brain barrier. LTH was blocked by inhibitors of protein and RNA synthesis, enhanced by protein kinase A (PKA) activators and reduced by PKA inhibitors, facilitated by angiotensin II and IV and disrupted by saralasin. The presence of angiotensins and related compounds in the crab brain was demonstrated. Diverse results suggest that LTH includes two components: an initial memory produced by spaced training and mainly expressed at an initial phase of testing, and a retraining memory produced by massed training and expressed at a later phase of testing (retraining). The initial memory would be associative, context specific and sensitive to cycloheximide, while the retraining memory would be nonassociative, context independent and insensitive to cycloheximide. PMID- 9361705 TI - Ca2+ dependence of gluconeogenesis stimulation by glucagon at different cytosolic NAD(+)-NADH redox potentials. AB - The influence of Ca2+ on hepatic gluconeogenesis was measured in the isolated perfused rat liver at different cytosolic NAD(+)-NADH potentials. Lactate and pyruvate were the gluconeogenic substrates and the cytosolic NAD(+)-NADH potentials were changed by varying the lactate to pyruvate ratios from 0.01 to 100. The following results were obtained: a) gluconeogenesis from lactate plus pyruvate was not affected by Ca(2+)-free perfusion (no Ca2+ in the perfusion fluid combined with previous depletion of the intracellular pools); gluconeogenesis was also poorly dependent on the lactate to pyruvate ratios in the range of 0.1 to 100; only for a ratio equal to 0.01 was a significantly smaller gluconeogenic activity observed in comparison to the other ratios. b) In the presence of Ca2+, the increase in oxygen uptake caused by the infusion of lactate plus pyruvate at a ratio equal to 10 was the most pronounced one; in Ca(2+)-free perfusion the increase in oxygen uptake caused by lactate plus pyruvate infusion tended to be higher for all lactate to pyruvate ratios; the most pronounced difference was observed for lactate/pyruvate ratio equal to 1. c) In the presence of Ca2+ the effects of glucagon on gluconeogenesis showed a positive correlation with the lactate to pyruvate ratios; for a ratio equal to 0.01 no stimulation occurred, but in the 0.1 to 100 range stimulation increased progressively, producing a clear parabolic dependence between the effects of glucagon and the lactate to pyruvate ratio. d) In the absence of Ca2+ the relationship between the changes caused by glucagon in gluconeogenesis and the lactate to pyruvate ratio was substantially changed; the dependence curve was no longer parabolic but sigmoidal in shape with a plateau beginning at a lactate/pyruvate ratio equal to 1; there was inhibition at the lactate to pyruvate ratios of 0.01 and 0.1 and a constant stimulation starting with a ratio equal to 1; for the lactate to pyruvate ratios of 10 and 100, stimulation caused by glucagon was much smaller than that found when Ca2+ was present. e) The effects of glucagon on oxygen uptake in the presence of Ca2+ showed a parabolic relationship with the lactate to pyruvate ratios which was closely similar to that found in the case of gluconeogenesis; the only difference was that inhibition rather than stimulation of oxygen uptake was observed for a lactate to pyruvate ratio equal to 0.01; progressive stimulation was observed in the 0.1 to 100 range. f) In the absence of Ca2+ the effects of glucagon on oxygen uptake were different; the dependence curve was sigmoidal at the onset, with a well defined maximum at a lactate to pyruvate ratio equal to 1; this maximum was followed by a steady decline at higher ratios; at the ratios of 0.01 and 0.1 inhibition took place; oxygen uptake stimulation caused by glucagon was generally lower in the absence of Ca2+ except when the lactate to pyruvate ratio was equal to 1. The results of the present study demonstrate that stimulation of gluconeogenesis by glucagon depends on Ca2+. However, Ca2+ is only effective in helping gluconeogenesis stimulation by glucagon at highly negative redox potentials of the cytosolic NAD(+)-NADH system. The triple interdependence of glucagon-Ca(2+)-NAD(+)-NADH redox potential reveals highly complex interrelations that can only be partially understood at the present stage of knowledge. PMID- 9361706 TI - Ultrastructural and biochemical detection of biotin and biotinylated polypeptides in Schistosoma mansoni. AB - Biotinylation is proposed for the identification of surface proteins in Schistosoma mansoni using the streptavidin-HRP conjugate for the detection of labeled polypeptides. However, control samples also showed several endogenous biotinylated polypeptides. In an attempt to determine the possibility of nonspecific binding between the streptavidin-HRP conjugate and polypeptides from S. mansoni, the conjugate was blocked with biotinamidecaproate-N hydroxysuccinimide ester (BcapNHS) before biotin-streptavidin blotting. No bands were detected on the nitrocellulose sheet, demonstrating the specific recognition of biotin by the streptavidin present in the conjugate. Whole cercariae and cercarial bodies and tails showed several endogenous biotinylated polypeptides. The biotin concentration was 13 micrograms/190,000 cercariae. Adult worms presented less endogenous biotinylated polypeptides than cercariae. These results may be due to changes in the environment from aerobic to anaerobic conditions when cercarial bodies (schistosomula) are transformed into adult worms and a decrease in CO2 production may occur. Cercariae, cercarial bodies and adult male worms were examined by transmission electron microscopy employing an avidin colloidal gold conjugate for the detection of endogenous biotin. Gold particles were distributed mainly on the muscle fibers, but dispersed granules were observed in the tegument, mitochondria and cytosol. The discovery of endogenous biotin in S. mansoni should be investigated in order to clarify the function of this vitamin in the parasite. PMID- 9361707 TI - Fibronectin in the ascitic fluid of cirrhotic patients: correlation with biochemical risk factors for the development of spontaneous bacterial peritonitis. AB - Cirrhotic patients (23 with alcoholic cirrhosis, 5 with posthepatitic cirrhosis and 2 with cryptogenic cirrhosis) with ascites and portal hypertension were studied and divided into two groups corresponding to high or low risk to develop spontaneous bacterial peritonitis (SBP) related to the concentration of total protein in the ascitic fluid (A-TP): group I (high risk): A-TP < or = 1.5 g/dl and group II (low risk): A-TP > 1.5 g/dl. Fibronectin (FN), C3 and C4 concentrations were measured by radial immunodiffusion while total protein was measured by the biuret method. The mean values (group I vs group II) of C3 (12.59 +/- 4.72 vs 24.53 +/- 15.58 mg/dl), C4 (4.26 +/- 3.87 vs 7.26 +/- 4.14 mg/dl) and FN (50.47 +/- 12.49 vs 75.89 +/- 24.70 mg/dl) in the ascitic fluid were significantly lower (P < 0.05) in the group considered to be at high risk for SBP. No significant difference was observed in the plasma/ascites fibronectin ratio (3.91 +/- 1.21 vs 3.80 +/- 1.26) or gradient (131.46 +/- 64.01 vs 196.96 +/ 57.38) between groups. Fibronectin in ascites was significantly correlated to C3 (r = 0.76), C4 (r = 0.58), total protein (r = 0.73) and plasma FN (r = 0.58) (P < 0.05). The data suggest that the FN concentration in ascites is related to the opsonic capacity of this fluid, and that its concentration in the ascitic fluid may be a biochemical risk factor indicator for the development of spontaneous bacterial peritonitis. PMID- 9361709 TI - An experimental model for the measurement of renal function after temporary ureteral obstruction in the rat. AB - We present the results obtained with a ureterovesical implant after ipsilateral ureteral obstruction in the rat, suitable for the study of renal function after deobstruction in these animals. Thirty-seven male Wistar rats weighing 260 to 300 g were submitted to distal right ureteral ligation and divided into 3 groups, A (N = 13, 1 week of obstruction), B (N = 14, 2 weeks of obstruction) and C (N = 10, 3 weeks of obstruction). The animals were then submitted to ureterovesical implantation on the right side and nephrectomy on the left side. During the 4 week follow-up period serum levels of urea and creatinine were measured on the 2nd, 7th, 14th, 21st and 28th day and compared with preoperative levels. The ureterovesical implantation included a psoas hitch procedure and the ureter was pulled into the bladder using a transvesical suture. During the first week of the postoperative period 8 animals died, 4/13 in group A (1 week of obstruction) and 4/14 in group B (2 weeks of obstruction). When compared to preoperative serum levels, urea and creatinine showed a significant increase (P < 0.05) on the 2nd postoperative day in groups A and B, with a gradual return to lower levels. However, the values in group B animals were higher than those in group A at the end of the follow-up. In group C, 2/10 animals (after 3 weeks of obstruction) were sacrificed at the time of ureterovesical implantation due to infection of the obstructed kidneys. The remaining animals in this group were operated upon but all of them died during the first week of follow-up due to renal failure. This technique of ureterovesical implantation in the rat provides effective drainage of the upper urinary tract, permitting the development of an experimental model for the study of long-term renal function after a period of ureteral obstruction. PMID- 9361708 TI - Disaccharidase levels in normal epithelium of the small intestine of rats with iron-deficiency anemia. AB - Iron-deficiency anemia is the nutritional deficiency most frequently occurring throughout the world, which manifests as a complex systemic disease involving all cells, affecting enzyme activities and modifying protein synthesis. In view of these considerations, the objective of the present study was to determine the effects of iron-deficiency anemia on disaccharidases and on the epithelial morphokinetics of the jejunal mucosa. Newly weaned male Wistar rats were divided into 4 groups of 10 animals each: C6w received a standard ration containing 36 mg elemental iron per kg ration for 6 weeks; E6w received an iron-poor ration (5-8 mg/kg ration) for 6 weeks; C10w received an iron-rich ration (36 mg/kg ration) for 10 weeks; E10w received an iron-poor ration for 6 weeks and then an iron-rich ration (36 mg/kg) for an additional 4 weeks. Jejunal fragments were used to measure disaccharidase content and to study cell proliferation. The following results were obtained: 1) a significant reduction (P < 0.001) of animal weight, hemoglobin (Hb), serum iron and total iron-binding capacity (TIBC) in group E6w as compared to C6w; reversal of the alterations in Hb, serum iron and TIBC with iron repletion (E10w = C10w); animal weights continued to be significantly different in groups E10w and C10w. 2) Sucrase and maltase levels were unchanged; total and specific lactase levels were significantly lower in group E6w and this reduction was reversed by iron repletion (E10w = C10w). 3) The cell proliferation parameters did not differ between groups. On the basis of these results, we conclude that lactase production was influenced by iron deficiency and that this fact was not related to changes in cell population and proliferation in the intestinal mucosa. PMID- 9361710 TI - Ultrastructural study of the neovagina following the utilization of human amniotic membrane for treatment of congenital absence of the vagina. AB - We present an ultrastructural study of the utilization of human amniotic membrane in the treatment of congenital absence of the vagina in 10 patients. All patients were surgically treated with application of an amniotic membrane graft using the modified McIndoe and Bannister technique. Sixty days after surgery, samples of the vaginal neoepithelium were collected for transmission electron microscopy analysis. The ultrastructural findings consisted of a lining of mature squamous epithelium indicating the occurrence of metaplasia of the amniotic epithelium into the vaginal epithelium. The cells were arranged in layers as in the normal vaginal epithelium, i.e., superficial, intermediate and deep layers. There were desmosomes and cytoplasmic intermediate cytokeratin filaments, as well as some remnant features of the previous amniotic epithelium. These findings suggest that human amniotic membrane is able to complete metaplasia into squamous cells but the mechanism of this cellular transformation is unknown. PMID- 9361711 TI - The renal and hepatic distribution of Bence Jones proteins depends on glycosylation: a scintigraphic study in rats. AB - The aim of the present study was to evaluate renal and liver distribution of two monoclonal immunoglobulin light chains. The chains were purified individually from the urine of patients with multiple myeloma and characterized as lambda light chains with a molecular mass of 28 kDa. They were named BJg (high amount of galactose residues exposed) and BJs (sialic acid residues exposed) on the basis of carbohydrate content. A scintigraphic study was performed on male Wistar rats weighing 250 g for 60 min after i.v. administration of 1 mg of each protein (7.4 MBq), as the intact proteins and also after carbohydrate oxidation. Images were obtained with a Siemens gamma camera with a high-resolution collimator and processed with a MicroDelta system. Hepatic and renal distribution were established and are reported as percent of injected dose. Liver uptake of BJg was significantly higher than liver uptake of BJs (94.3 vs 81.4%) (P < 0.05). This contributed to its greater removal from the intravascular compartment, and consequently lower kidney accumulation of BJg in comparison to BJs (5.7 vs 18.6%) (P < 0.05). After carbohydrate oxidation, there was a decrease in hepatic accumulation of both proteins and consequently a higher renal overload. The tissue distribution of periodate-treated BJg was similar to that of native BJs: 82.7 vs 81.4% in the liver and 17.3 vs 18.6% in the kidneys. These observations indicate the important role of sugar residues of Bence Jones proteins for their recognition by specific membrane receptors, which leads to differential tissue accumulation and possible toxicity. PMID- 9361712 TI - Inflammatory and anti-inflammatory effects of soybean agglutinin. AB - Soybean agglutinin (SBA) lectin, a protein present in raw soybean meals, can bind to and be extensively endocytosed by intestinal epithelial cells, being nutritionally toxic for most animals. In the present study we show that SBA (5 200 micrograms/cavity) injected into different cavities of rats induced a typical inflammatory response characterized by dose-dependent exudation and neutrophil migration 4 h after injection. This effect was blocked by pretreatment with glucocorticoid (0.5 mg/kg) or by co-injection of N-acetyl-galactosamine (100 x [M] lectin), but not of other sugars (100 x [M] lectin), suggesting an inflammatory response related to the lectin activity. Neutrophil accumulation was not dependent on a direct effect of SBA on the macrophage population since the effect was not altered when the number of peritoneal cells was increased or decreased in vivo. On the other hand, SBA showed chemotactic activity for human neutrophils in vitro. A slight increase in mononuclear cells was observed 48 h after i.p. injection of SBA. Phenotypic analysis of these cells showed an increase in the CD4+/CD8- lymphocyte population that returned to control levels after 15 days, suggesting the development of an immune response. SBA-stimulated macrophages presented an increase in the expression of CD11/CD18 surface molecules and showed some characteristics of activated cells. After intravenous administration, SBA increased the number of circulating neutrophils and inhibited in a dose-dependent manner the neutrophil migration induced by i.p. injection of carrageenan into peritoneal cavities. The co-injection of N-acetyl-galactosamine or mannose, but not glucose or fucose, inhibited these effects. The data indicate that soybean lectin is able to induce a local inflammatory reaction but has an anti-inflammatory effect when present in circulating blood. PMID- 9361713 TI - Induction of neutralizing antibodies in mice immunized with scorpion toxins detoxified by liposomal entrapment. AB - The possibility of producing neutralizing antibodies against the lethal effects of scorpion toxins was evaluated in the mouse model by immunization with an immunogen devoid of toxicity. A toxic fraction (5 mg) from the venom of the scorpion Tityus serrulatus was entrapped in sphingomyelin-cholesterol liposomes. The liposomes were treated for 1 h at 37 degrees C with a 1% (w/w) trypsin solution in 0.2 M sodium carbonate buffer, pH 8.3. This treatment led to a strong reduction in venom toxicity. Immunization was performed as follows: mice were injected s.c. with 20 micrograms of the liposome-entrapped toxic fraction on days 1 and 21 and a final injection (20 micrograms) was administered i.p. on day 36. After injection of the immunogen, all mice developed an IgG response which was shown to be specific for the toxic antigen. The antibodies were measured 10 days after the end of the immunization protocol. In an in vitro neutralization assay we observed that pre-incubation of a lethal dose of the toxic fraction with immune serum strongly reduced its toxicity. In vivo protection assays showed that mice with anti-toxin antibodies could resist the challenge with the toxic fraction, which killed, 30 min after injection, all non-immune control mice. PMID- 9361714 TI - Hormonal response during a fenfluramine-associated panic attack. AB - Secretion curves for prolactin, cortisol, TSH, and GH from a 37-year old woman with dysthymia and panic disorder with agoraphobia were determined one day prior to (day I), and during a panic attack (day II) associated with an oral dose of 60 mg dl-fenfluramine, a drug known to increase anticipatory anxiety. The increased cortisol secretion observed is discussed in relation to the hormonal correlates of anxiety and the possible role of depression, dl-fenfluramine, and serotonergic receptor sensitivity. PMID- 9361715 TI - Reactivity of the isolated perfused rat tail vascular bed. AB - Isolated segments of the perfused rat tail artery display a high basal tone when compared to other isolated arteries such as the mesenteric and are suitable for the assay of vasopressor agents. However, the perfusion of this artery in the entire tail has not yet been used for functional studies. The main purpose of the present study was to identify some aspects of the vascular reactivity of the rat tail vascular bed and validate this method to measure vascular reactivity. The tail severed from the body was perfused with Krebs solution containing different Ca2+ concentrations at different flow rates. Rats were anesthetized with sodium pentobarbital (65 mg/kg) and heparinized (500 U). The tail artery was dissected near the tail insertion, cannulated and perfused with Krebs solution plus 30 microM EDTA at 36 degrees C and 2.5 ml/min and the procedures were started after equilibration of the perfusion pressure. In the first group a dose-response curve to phenylephrine (PE) (0.5, 1, 2 and 5 micrograms, bolus injection) was obtained at different flow rates (1.5, 2.5 and 3.5 ml/min). The mean perfusion pressure increased with flow as well as PE vasopressor responses. In a second group the flow was changed (1.5, 2, 2.5, 3 and 3.5 ml/min) at different Ca2+ concentrations (0.62, 1.25, 2.5 and 3.75 mM) in the Krebs solution. Increasing Ca2+ concentrations did not alter the flow-pressure relationship. In the third group a similar protocol was performed but the rat tail vascular bed was perfused with Krebs solution containing PE (0.1 microgram/ml). There was an enhancement of the effect of PE with increasing external Ca2+ and flow. PE vasopressor responses increased after endothelial damage with air and CHAPS, suggesting an endothelial modulation of the tone of the rat tail vascular bed. These experiments validate the perfusion of the rat tail vascular bed as a method to investigate vascular reactivity. PMID- 9361716 TI - Validation of transit-time flowmetry for chronic measurements of regional blood flow in resting and exercising rats. AB - The objective of the present study was to validate the transit-time technique for long-term measurements of iliac and renal blood flow in rats. Flow measured with ultrasonic probes was confirmed ex vivo using excised arteries perfused at varying flow rates. An implanted 1-mm probe reproduced with accuracy different patterns of flow relative to pressure in freely moving rats and accurately quantitated the resting iliac flow value (on average 10.43 +/- 0.99 ml/min or 2.78 +/- 0.3 ml min-1 100 g body weight-1). The measurements were stable over an experimental period of one week but were affected by probe size (resting flows were underestimated by 57% with a 2-mm probe when compared with a 1-mm probe) and by anesthesia (in the same rats, iliac flow was reduced by 50-60% when compared to the conscious state). Instantaneous changes of iliac and renal flow during exercise and recovery were accurately measured by the transit-time technique. Iliac flow increased instantaneously at the beginning of mild exercise (from 12.03 +/- 1.06 to 25.55 +/- 3.89 ml/min at 15 s) and showed a smaller increase when exercise intensity increased further, reaching a plateau of 38.43 +/- 1.92 ml/min at the 4th min of moderate exercise intensity. In contrast, exercise induced reduction of renal flow was smaller and slower, with 18% and 25% decreases at mild and moderate exercise intensities. Our data indicate that transit-time flowmetry is a reliable method for long-term and continuous measurements of regional blood flow at rest and can be used to quantitate the dynamic flow changes that characterize exercise and recovery. PMID- 9361718 TI - Utilization of microsatellites for the analysis of genomic alterations in colorectal cancers in Brazil. AB - Two different pathogenetic mechanisms are proposed for colorectal cancers. One, the so-called "classic pathway", is the most common and depends on multiple additive mutational events (germline and/or somatic) in tumor suppressor genes and oncogenes, frequently involving chromosomal deletions in key genomic regions. Methodologically this pathway is recognizable by the phenomenon of loss of heterozygosity. On the other hand, the "mutator pathway" depends on early mutational loss of the mismatch repair system (germline and/or somatic) leading to accelerated accumulation of gene mutations in critical target genes and progression to malignancy. Methodologically this second pathway is recognizable by the phenomenon of microsatellite instability. The distinction between these pathways seems to be more than academic since there is evidence that the tumors emerging from the mutator pathway have a better prognosis. We report here a very simple methodology based on a set of tri-, tetra- and pentanucleotide repeat microsatellites allowing the simultaneous study of microsatellite instability and loss of heterozygosity which could allocate 70% of the colorectal tumors to the classic or the mutator pathway. The ease of execution of the methodology makes it suitable for routine clinical typing. PMID- 9361717 TI - Role of mast cell- and non-mast cell-derived inflammatory mediators in immunologic induction of synaptic plasticity. AB - We have previously discovered a long-lasting enhancement of synaptic transmission in mammal autonomic ganglia caused by immunological activation of ganglionic mast cells. Subsequent to mast cell activation, lipid and peptide mediators are released which may modulate synaptic function. In this study we determined whether some mast cell-derived mediators, prostaglandin D2 (PGD2; 1.0 microM), platelet aggregating factor (PAF; 0.3 microM) and U44619 (a thromboxane analogue; 1.0 microM), and also endothelin-1 (ET-1; 0.5 microM) induce synaptic potentiation in the guinea pig superior cervical ganglion (SCG), and compared their effects on synaptic transmission with those induced by a sensitizing antigen, ovalbumin (OVA; 10 micrograms/ml). The experiments were carried out on SCGs isolated from adult male guinea pigs (200-250 g) actively sensitized to OVA, maintained in oxygenated Locke solution at 37 degrees C. Synaptic potentiation was measured through alterations of the integral of the post-ganglionic compound action potential (CAP). All agents tested caused long-term (LTP; duration > or = 30 min) or short-term (STP; < 30 min) potentiation of synaptic efficacy, as measured by the increase in the integral of the post-ganglionic CAP. The magnitude of mediator-induced potentiation was never the same as the antigen induced long-term potentiation (A-LTP). The agent that best mimicked the antigen was PGD2, which induced a 75% increase in CAP integral for LTP (antigen: 94%) and a 34% increase for STP (antigen: 91%). PAF-, U44619-, and ET-1-induced increases in CAP integral ranged for LTP from 34 to 47%, and for STP from 0 to 26%. These results suggest that the agents investigated may participate in the induction of A-LTP. PMID- 9361719 TI - Large-scale production and purification of recombinant protein from an insect cell/baculovirus system in Erlenmeyer flasks: application to the chicken poly(ADP ribose) polymerase catalytic domain. AB - A simple and inexpensive shaker/Erlenmeyer flask system for large-scale cultivation of insect cells is described and compared to a commercial spinner system. On the basis of maximum cell density, average population doubling time and overproduction of recombinant protein, a better result was obtained with a simpler and less expensive bioreactor consisting of Erlenmeyer flasks and an ordinary shaker waterbath. Routinely, about 90 mg of pure poly(ADP-ribose) polymerase catalytic domain was obtained for a total of 3 x 10(9) infected cells in three liters of culture. PMID- 9361720 TI - Vitamin D receptor alleles and bone mineral density in a normal premenopausal Brazilian female population. AB - Studies on the association between vitamin D receptor (VDR) polymorphism and bone mineral density (BMD) in different populations have produced conflicting results probably due to ethnic differences in the populations studied. The Brazilian population is characterized by a very broad genetic background and a high degree of miscegenation. Of an initial group of 164, we studied 127 women from the city of Sao Paulo, aged 20 to 47 years (median, 31 years), with normal menses, a normal diet and no history of diseases or use of any medication that could alter BMD. VDR genotype was assessed by PCR amplification followed by BsmI digestion of DNA isolated from peripheral leukocytes. BMD was measured using dual energy X-ray absorptiometry (Lunar DPX) at the lumbar site (L2-L4) and femoral neck. Most of the women (77.6%) were considered to be of predominantly European ancestry (20.6% of them reported also native American ancestry), 12.8% were of African-Brazilian ancestry and 9.6% of Asian ancestry, 41.0% (52) were classified as bb, 48.8% (62) as Bb and 10.2% (13) as BB. The BB, Bb and bb groups did not differ in age, height, weight, body mass index or age at menarche. Lumbar spine BMD was significantly higher in the bb group (1.22 +/- 0.16 g/cm2) than in the BB group (1.08 +/- 0.14; P < 0.05), and the Bb group presented an intermediate value (1.17 +/- 0.15). Femoral neck BMD was higher in the bb group (0.99 +/- 0.11 g/cm2) compared to Bb (0.93 +/- 0.12) and BB (0.90 +/- 0.09) (P < 0.05). These data indicate that there is a significant correlation between the VDR BsmI genotype and BMD in healthy Brazilian premenopausal females. PMID- 9361721 TI - Minimal doses of hydroxyurea for sickle cell disease. AB - The use of hydroxyurea (HU) can improve the clinical course of sickle cell disease. However, several features of HU treatment remain unclear, including the predictability of drug response and determination of adequate doses, considering positive responses and minimal side effects. In order to identify adequate doses of HU for treatment of sickle cell disease, 10 patients, 8 with sickle cell anemia and 2 with S beta thalassemia (8SS, 2S beta), were studied for a period of 6 to 19 months in an open label dose escalation trial (10 to 20 mg kg-1 day-1). Hemoglobin (Hb), fetal hemoglobin (Hb F) and mean corpuscular volume (MCV) values and reticulocyte, neutrophil and platelet counts were performed every two weeks during the increase of the HU dose and every 4 weeks when the maximum HU dose was established. Reduction in the number of vasoocclusive episodes was also considered in order to evaluate the efficiency of the treatment. The final Hb and Hb F concentrations, and MCV values were significantly higher than the initial values, while the final reticulocyte and neutrophil counts were significantly lower. There was an improvement in the concentration of Hb (range: 0.7-2.0 g/dl) at 15 mg HU kg-1 day-1, but this concentration did not increase significantly when the HU dose was raised to 20 mg kg-1 day-1. The concentration of Hb F increased significantly (range: 1.0-18.1%) when 15 mg HU was used, and continued to increase when the dose was raised to 20 mg kg-1 day-1. The final MCV values increased 11-28 fl (femtoliters). However, reticulocyte (range: 51-205 x 10(9)/l) and neutrophil counts (range: 9.5-1.3 x 10(9)/l) obtained at this dose were significantly lower than those obtained with 15 mg kg-1 day-1. All patients reported a decrease in frequency or severity of vasoocclusive episodes. These results suggest that a hydroxyurea dose of 15 mg kg-1 day-1 seems to be adequate for treatment of sickle cell disease in view of the minimal side effects observed and the improvement in laboratory and clinical parameters. PMID- 9361722 TI - Hyperthermia increases the metastatic potential of murine melanoma. AB - Hyperthermia, either alone or combined with radio-, immuno- or chemotherapy, can control tumor growth, but its effect on metastasis is still controversial. In the present study, we investigated the influence of hyperthermia on the metastatic potential of B16-F10 murine melanoma cells. Incubation of melanoma cells at 43 degrees C for 30 min led to a significant decrease in cell viability. About half of the cells survived the acute exposure to heat. These thermoresistant cells displayed a longer lag phase as compared to control unheated B16-F10 melanoma cells. Other parameters of cell growth such as doubling time and saturation density were equivalent in both control and thermoresistant cells. Both control and treated cells were adherent, but thermoresistant cells failed to spread during the first 48 h after heat exposure. B16-F10 cells colonize the lungs of C57BL/6J mice when injected intravenously; the number of lung colonies is a measure of the metastatic potential of injected cells. Median values of 22, 10.5 and 31 colonies per injected mouse were observed for control cells, cells heated to 43 degrees C for 30 min and thermoresistant cells, respectively, with statistically significant differences between groups (Mann-Whitney test, P < 0.02). Thus, despite its cytotoxic action, heat exposure induced the acquisition of a more metastatic phenotype in a subpopulation of B16-F10 cells. PMID- 9361723 TI - Hepatic damage during acute pancreatitis in the rat. AB - We studied the alterations in the metabolism of liver mitochondria in rats with acute pancreatitis. Male Wistar rats were allocated to a control group (group I) and to five other groups corresponding to 2, 4, 12, 24 and 48 h after the induction of acute pancreatitis by the injection of 5% sodium taurocholate into the pancreatic duct. Sham-operated animals were submitted to the same surgical steps except for the induction of acute pancreatitis. Mitochondrial oxidation and phosphorylation were measured polarographically by determining oxygen consumption without ADP (basal respiration, state 4) and in the presence of ADP (activated respiration, state 3). Serum amylase, transaminases (ALT and AST) and protein were also determined. Ascitic fluid, contents of amylase, trypsin and total protein were also determined and arterial blood pressure was measured in all groups. In ascitic fluid, trypsin and amylase increased reaching a maximum at 2 and 4 h, respectively. Serum amylase increased at 2 h reaching a maximum at 4 h. Serum transaminase levels increased at 12 and 24 h. After 2 h (and also 4 h) there was an increase in state 4 respiration (45.65 +/- 1.79 vs 28.96 +/- 1.50) and a decrease in respiration control rate (3.53 +/- 0.09 vs 4.45 +/- 0.08) and in the ADP/O ratio (1.77 +/- 0.02 vs 1.91 +/- 0.01) compared to controls (P < 0.05). These results indicate a disruption of mitochondrial function, which recovered after 12 h. In the 48-h groups there was mitochondrial damage similar to that occurring in ischemic lesion. Beat-to-beat analysis (30 min) showed that arterial blood pressure remained normal up to 24 h (111 +/- 3 mmHg) while a significant decrease occurred in the 48-h group (91 +/- 4 mmHg). These data suggest biphasic damage in mitochondrial function in acute pancreatitis: an initial uncoupled phase, possibly secondary to enzyme activity, followed by a temporary recovery and then a late and final dysfunction, associated with arterial hypotension, possibly related to ischemic damage. PMID- 9361724 TI - Chronic imipramine treatment-induced changes in acetylcholinesterase (EC 3.1.1.7) activity in discrete rat brain regions. AB - Cholinergic as well as monoaminergic neurotransmission seems to be involved in the etiology of affective disorders. Chronic treatment with imipramine, a classical antidepressant drug, induces adaptive changes in monoaminergic neurotransmission. In order to identify possible changes in cholinergic neurotransmission we measured total, membrane-bound and soluble acetylcholinesterase (Achase) activity in several rat brain regions after chronic imipramine treatment. Changes in Achase activity would indicate alterations in acetylcholine (Ach) availability to bind to its receptors in the synaptic cleft. Male rats were treated with imipramine (20 mg/kg, i.p.) for 21 days, once a day. Twenty-four hours after the last dose the rats were sacrificed and homogenates from several brain regions were prepared. Membrane-bound Achase activity (nmol thiocholine formed min-1 mg protein-1) after chronic imipramine treatment was significantly decreased in the hippocampus (control = 188.8 +/- 19.4, imipramine = 154.4 +/- 7.5, P < 0.005) and striatum (control = 850.9 +/- 59.6, imipramine = 742.5 +/- 34.7, P < 0.005). A small increase in total Achase activity was observed in the medulla oblongata and pons. No changes in enzyme activity were detected in the thalamus or total cerebral cortex. Since the levels of Achase seem to be enhanced through the interaction between Ach and its receptors, a decrease in Achase activity may indicate decreased Ach release by the nerve endings. Therefore, our data indicate that cholinergic neurotransmission is decreased after chronic imipramine treatment which is consistent with the idea of an interaction between monoaminergic and cholinergic neurotransmission in the antidepressant effect of imipramine. PMID- 9361725 TI - Involvement of hippocampal AMPA glutamate receptor changes and the cAMP/protein kinase A/CREB-P signalling pathway in memory consolidation of an avoidance task in rats. AB - Training in step-down inhibitory avoidance (0.3-mA footshock) is followed by biochemical changes in rat hippocampus that strongly suggest an involvement of quantitative changes in glutamate AMPA receptors, followed by changes in the dopamine D1 receptor/cAMP/ protein kinase A (PKA)/CREB-P signalling pathway in memory consolidation. AMPA binding to its receptor and levels of the AMPA receptor-specific subunit GluR1 increase in the hippocampus within the first 3 h after training (20-70%). Binding of the specific D1 receptor ligand, SCH23390, and cAMP levels increase within 3 or 6 h after training (30-100%). PKA activity and CREB-P levels show two peaks: a 35-40% increase 0 h after training, and a second increase 3-6 h later (35-60%). The results correlate with pharmacological findings showing an early post-training involvement of AMPA receptors, and a late involvement of the D1/cAMP/PKA/CREB-P pathway in memory consolidation of this task. PMID- 9361726 TI - Agents that affect cAMP levels or protein kinase A activity modulate memory consolidation when injected into rat hippocampus but not amygdala. AB - Male Wistar rats were trained in one-trial step-down inhibitory avoidance using a 0.4-mA footshock. At various times after training (0, 1.5, 3, 6 and 9 h for the animals implanted into the CA1 region of the hippocampus; 0 and 3 h for those implanted into the amygdala), these animals received microinfusions of SKF38393 (7.5 micrograms/side), SCH23390 (0.5 microgram/side), norepinephrine (0.3 microgram/side), timolol (0.3 microgram/side), 8-OH-DPAT (2.5 micrograms/side), NAN-190 (2.5 micrograms/side), forskolin (0.5 microgram/side), KT5720 (0.5 microgram/side) or 8-Br-cAMP (1.25 micrograms/side). Rats were tested for retention 24 h after training. When given into the hippocampus 0 h post-training, norepinephrine enhanced memory whereas KT5720 was amnestic. When given 1.5 h after training, all treatments were ineffective. When given 3 or 6 h post training, 8-Br-cAMP, forskolin, SKF38393, norepinephrine and NAN-190 caused memory facilitation, while KT5720, SCH23390, timolol and 8-OH-DPAT caused retrograde amnesia. Again, at 9 h after training, all treatments were ineffective. When given into the amygdala, norepinephrine caused retrograde facilitation at 0 h after training. The other drugs infused into the amygdala did not cause any significant effect. These data suggest that in the hippocampus, but not in the amygdala, a cAMP/protein kinase A pathway is involved in memory consolidation at 3 and 6 h after training, which is regulated by D1, beta, and 5HT1A receptors. This correlates with data on increased post-training cAMP levels and a dual peak of protein kinase A activity and CREB-P levels (at 0 and 3-6 h) in rat hippocampus after training in this task. These results suggest that the hippocampus, but not the amygdala, is involved in long-term storage of step-down inhibitory avoidance in the rat. PMID- 9361728 TI - Sucrose ingestion causes opioid analgesia. AB - The intake of saccharin solutions for relatively long periods of time causes analgesia in rats, as measured in the hot-plate test, an experimental procedure involving supraspinal components. In order to investigate the effects of sweet substance intake on pain modulation using a different model, male albino Wistar rats weighing 180-200 g received either tap water or sucrose solutions (250 g/l) for 1 day or 14 days as their only source of liquid. Each rat consumed an average of 15.6 g sucrose/day. Their tail withdrawal latencies in the tail-flick test (probably a spinal reflex) were measured immediately before and after this treatment. An analgesia index was calculated from the withdrawal latencies before and after treatment. The indexes (mean +/- SEM, N = 12) for the groups receiving tap water for 1 day or 14 days, and sucrose solution for 1 day or 14 days were 0.09 +/- 0.04, 0.10 +/- 0.05, 0.15 +/- 0.08 and 0.49 +/- 0.07, respectively. One way ANOVA indicated a significant difference (F(3, 47) = 9.521, P < 0.001) and the Tukey multiple comparison test (P < 0.05) showed that the analgesia index of the 14-day sucrose-treated animals differed from all other groups. Naloxone treated rats (N = 7) receiving sucrose exhibited an analgesia index of 0.20 +/- 0.10 while rats receiving only sucrose (N = 7) had an index of 0.68 +/- 0.11 (t = 0.254, 10 degrees of freedom, P < 0.03). This result indicates that the analgesic effect of sucrose depends on the time during which the solution is consumed and extends the analgesic effects of sweet substance intake, such as saccharin, to a model other than the hot-plate test, with similar results. Endogenous opioids may be involved in the central regulation of the sweet substance-produced analgesia. PMID- 9361727 TI - Anticonvulsant and proconvulsant roles of nitric oxide in experimental epilepsy models. AB - The effect of acute (120 mg/kg) and chronic (25 mg/kg, twice a day, for 4 days) intraperitonial injection of the nitric oxide (NO) synthase (NOS) inhibitor NG nitro-L-arginine (L-NOARG) was evaluated on seizure induction by drugs such as pilocarpine and pentylenetetrazole (PTZ) and by sound stimulation of audiogenic seizure-resistant (R) and audiogenic seizure-susceptible (S) rats. Seizures were elicited by a subconvulsant dose of pilocarpine (100 mg/kg) only after NOS inhibition. NOS inhibition also simultaneously potentiated the severity of PTZ induced limbic seizures (60 mg/kg) and protected against PTZ-induced tonic seizures (80 mg/kg). The audiogenic seizure susceptibility of S or R rats did not change after similar treatments. In conclusion, proconvulsant effects of NOS inhibition are suggested to occur in the pilocarpine model and in the limbic components of PTZ-induced seizures, while an anticonvulsant role is suggested for the tonic seizures induced by higher doses of PTZ, revealing inhibitor-specific interactions with convulsant dose and also confirming the hypothesis that the effects of NOS inhibitors vary with the model of seizure. PMID- 9361729 TI - Food intake and weight of lactating rats maintained on different protein-calorie diets, and pup growth. AB - Studies on rats maintained on low-protein-calorie diets during the lactation period show that food intake decreases. This process results in weight loss and a delay in litter development. The purpose of the present study was to determine the alterations in food intake, maternal weight and litter growth during lactation when dams were exposed to diets with different levels of protein and carbohydrate. Female Wistar rats receiving one of 4 different diets, A (N = 14), B (N = 14), C (N = 9) and D (N = 9), were used. Diet A contained 16% protein and 66% carbohydrate; diet B, 6% protein and 77% carbohydrate; diet C, 6% protein and 66% carbohydrate; diet D, 16% protein and 56% carbohydrate. Thus, C and D diets were hypocaloric, while A and B were isocaloric. The intake of a low-protein diet in groups B and C affected the weight of dams and litters during the last two weeks of lactation, while the low-calorie diets limited the growth of D litters at 21 days compared with A litters, but had no effect on the weight of D dams. Group B showed an increase in intake during the first five days of lactation, resulting in a behavioral calorie compensation due to the increase in carbohydrate content, but the intake decreased during the last part of lactation. Food intake regulation predominantly involves the recruitment of a variety of peripheral satiety systems that attempt to decrease the central feeding command system. PMID- 9361730 TI - Developmental and behavioral effects of postnatal amitraz exposure in rats. AB - The effects of postnatal amitraz exposure on physical and behavioral parameters were studied in Wistar rats, whose lactating dams received the pesticide (10 mg/kg) orally on days 1, 4, 7, 10, 13, 16 and 19 of lactation; control dams received distilled water (1 ml/kg) on the same days. A total of 18 different litters (9 of them control and 9 experimental) born after a 21-day gestation were used. The results showed that the median effective time (ET50) for fur development, eye opening, testis descent and onset of the startle response were increased in rats postnatally exposed to amitraz (2.7, 15.1, 21.6 and 15.3 days, respectively) compared to those of the control pups (1.8, 14.0, 19.9 and 12.9 days, respectively). The ages of incisor eruption, total unfolding of the external ears, vaginal and ear opening and the time taken to perform the grasping hindlimb reflex were not affected by amitraz exposure. Pups from dams treated with amitraz during lactation took more time (in seconds) to perform the surface righting reflex on postnatal days (PND) 3 (25.0 +/- 2.0), 4 (12.3 +/- 1.2) and 5 (8.7 +/- 0.9) in relation to controls (10.6 +/- 1.2; 4.5 +/- 0.6 and 3.4 +/- 0.4, respectively); the climbing response was not changed by amitraz. Postnatal amitraz exposure increased spontaneous motor activity of male and female pups in the open-field on PND 16 (140 +/- 11) and 17 (124 +/- 12), and 16 (104 +/- 9), 17 (137 +/- 9) and 18 (106 +/- 8), respectively. Data on spontaneous motor activity of the control male and female pups were 59 +/- 11 and 69 +/- 10 for days 16 and 17 and 49 +/- 9, 48 +/- 7 and 56 +/- 7 for days 16, 17 and 18, respectively. Some qualitative differences were also observed in spontaneous motor behavior; thus, raising the head, shoulder and pelvis matured one or two days later in the amitraz-treated offspring. Postnatal amitraz exposure did not change locomotion and rearing frequencies or immobility time in the open-field on PND 30, 60 and 90. The present findings indicate that postnatal exposure to amitraz caused transient developmental and behavioral changes in the exposed offspring and suggest that further investigation of the potential health risk of amitraz exposure to developing human and animal offsprings may be warranted. PMID- 9361732 TI - Low-cost automatic activity data recording system. AB - We describe a low-cost, high quality device capable of monitoring indirect activity by detecting touch-release events on a conducting surface, i.e., the animal's cage cover. In addition to the detecting sensor itself, the system includes an IBM PC interface for prompt data storage. The hardware/software design, while serving for other purposes, is used to record the circadian activity rhythm pattern of rats with time in an automated computerized fashion using minimal cost computer equipment (IBM PC XT). Once the sensor detects a touch-release action of the rat in the upper portion of the cage, the interface sends a command to the PC which records the time (hours-minutes-seconds) when the activity occurred. As a result, the computer builds up several files (one per detector/sensor) containing a time list of all recorded events. Data can be visualized in terms of actograms, indicating the number of detections per hour, and analyzed by mathematical tools such as Fast Fourier Transform (FFT) or cosinor. In order to demonstrate method validation, an experiment was conducted on 8 Wistar rats under 12/12-h light/dark cycle conditions (lights on at 7:00 a.m.). Results show a biological validation of the method since it detected the presence of circadian activity rhythm patterns in the behavior of the rats. PMID- 9361731 TI - Acute extracellular fluid volume changes increase ileocolonic resistance to saline flow in anesthetized dogs. AB - We determined the effect of acute extracellular fluid volume changes on saline flow through 4 gut segments (ileocolonic, ileal, ileocolonic sphincter and proximal colon), perfused at constant pressure in anesthetized dogs. Two different experimental protocols were used: hypervolemia (iv saline infusion, 0.9% NaCl, 20 ml/min, volume up to 5% body weight) and controlled hemorrhage (up to a 50% drop in mean arterial pressure). Mean ileocolonic flow (N = 6) was gradually and significantly decreased during the expansion (17.1%, P < 0.05) and expanded (44.9%, P < 0.05) periods while mean ileal flow (N = 7) was significantly decreased only during the expanded period (38%, P < 0.05). Mean colonic flow (N = 7) was decreased during expansion (12%, P < 0.05) but returned to control levels during the expanded period. Mean ileocolonic sphincter flow (N = 6) was not significantly modified. Mean ileocolonic flow (N = 10) was also decreased after hemorrhage (retracted period) by 17% (P < 0.05), but saline flow was not modified in the other separate circuits (N = 6, 5 and 4 for ileal, ileocolonic sphincter and colonic groups, respectively). The expansion effect was blocked by atropine (0.5 mg/kg, i.v.) both on the ileocolonic (N = 6) and ileal (N = 5) circuits. Acute extracellular fluid volume retraction and expansion increased the lower gastrointestinal resistances to saline flow. These effects, which could physiologically decrease the liquid volume being supplied to the colon, are possible mechanisms activated to acutely balance liquid volume deficit and excess. PMID- 9361733 TI - Wheat bran- but not oat bran-enriched diets increase the mucosal height of the cecum and colon of newly weaned and aged rats. AB - The effect of diets enriched with oat or wheat bran (prepared by the addition of 300 g of each fiber to 1000 g of the regular diet), given for 8 weeks, on the mucosal height of the colon and cecum was investigated. Newly weaned (21 days old) and aged (12 months old) male Wistar rats were used in this study. As compared to controls, diets enriched with wheat bran provoked a significant increase in the mucosal height, whereas oat bran did not cause any effect. In newly weaned rats (21 days old), wheat bran increased the mucosal height (microns) in the cecum by 20% (mean +/- SEM for 8 rats; 169.1 +/- 5.2 and 202.9 +/- 8.0 for control and wheat bran, respectively) and in the colon (218.8 +/- 7.2 and 264.5 +/- 18.8 for control and wheat bran, respectively). A similar effect was observed in aged rats (12 months old), with an increase of 15% in the mucosal height (microns) of the cecum (mean +/- SEM of 8 rats; 193.2 +/- 8.6 and 223.7 +/ 8.3 for control and wheat bran, respectively) and of 17% in the colon (300.4 +/- 9.2 and 352.2 +/- 15.9 for control and wheat bran, respectively). PMID- 9361734 TI - Heterogeneity of glomerular perfusion and filtration induced by epinephrine and norepinephrine. AB - The role of catecholamines in the distribution of intrarenal blood flow and in single-nephron glomerular filtration rate (SNGFR) was evaluated in anesthetized Wistar rats by the Hanssen technique. Epinephrine (EPI) and norepinephrine (NOR) were infused to produce elevations of 20-30 mmHg in mean arterial pressure. Superficial and juxtamedullary nephron perfusion and filtration were determined by the presence of Prussian blue dye. In the control group, 100% of the nephrons presented a homogeneous pattern of perfusion and filtration. In contrast, a heterogeneous distribution of the dye was found even in the larger arteries (arciform and radial), indicating variable perfusion and filtration in both superficial and juxtamedullary nephrons. The effects of EPI and NOR were also evaluated in the superficial cortex by the micropuncture technique in two additional groups of Munich-Wistar rats. Mean SNGFR was 27% and 54% lower in the EPI- and NOR-treated groups, respectively. No change in mean intraglomerular hydraulic pressure was observed after EPI or NOR infusion in spite of a highly scattered pattern, indicating an important variability in perfusion along the superficial cortex, and/or different sensitivity of the pre- and post-glomerular arterioles. The present data suggest that EPI and NOR may affect intrarenal hemodynamics by modifying perfusion and filtration in both superficial and juxtamedullary glomeruli and not by shifting blood flow from superficial to juxtamedullary nephrons. The heterogeneous pattern of perfusion was a consequence of differential vasoconstriction along the intrarenal arteries, probably due to different density and/or sensitivity of the adrenergic receptor subtypes present in the intrarenal vascular tree. PMID- 9361735 TI - Fast and slow voltage modulation of apical Cl- permeability in toad skin at high [K+]. AB - The influence of voltage on the conductance of toad skin was studied to identify the time course of the activation/deactivation dynamics of voltage-dependent Cl- channels located in the apical membrane of mitochondrion-rich cells in this tissue. Positive apical voltage induced an important conductance inhibition which took a few seconds to fully develop and was instantaneously released by pulse inversion to negative voltage, indicating a short-duration memory of the inhibiting factors. Sinusoidal stimulation at 23.4 mM [Cl-] showed hysteresis in the current versus voltage curves, even at very low frequency, suggesting that the rate of voltage application was also relevant for the inhibition/releasing effect to develop. We conclude that the voltage modulation of apical Cl- permeability is essentially a fast process and the apparent slow components of activation/deactivation obtained in the whole skin are a consequence of a gradual voltage build-up across the apical membrane due to voltage sharing between apical and basolateral membranes. PMID- 9361736 TI - Markers, cofactors and staging systems in the study of HIV disease progression: a review. AB - This paper is aimed at providing a comprehensive review of markers, cofactors and staging systems used for HIV disease, focusing on some aspects that nowadays could even be considered historical, and advancing in current issues such as the prognostic value of viral load measurements, viral genotypic and phenotypic characterization, and new HIV disease treatment protocols. CD4+ cell values, combined with the new viral markers mentioned are promising as a parsimonious predictor set for defining both severity and progression. An adequate predictor of patient resource use for planning purposes still needs to be defined. PMID- 9361737 TI - Isoenzymes detect variation in populations of Triatoma brasiliensis (Hemiptera: Reduviidae: Triatominae). AB - Triatoma brasiliensis is one of the most important vectors of Chagas disease in the semiarid zone of the northeast of Brazil. Intraspecific morphological and behavioural variation has been reported for different populations. Results for four distinct populations using eight isoenzymes are reported here. The literature describes three subspecies: T. brasiliensis brasiliensis Neiva, 1911; T. brasiliensis melanica Neiva & Lent, 1941 and T. brasiliensis macromelasoma Galvao, 1956. These subspecies differ mainly in their cuticle colour pattern and were regarded as synonyms by Lent and Wygodzinsky (1979). In order to evaluate whether the chromatic pattern is a morphological variation of different melanic forms within T. brasiliensis or due to interspecific variation, field collections were performed in localities where these three subspecies have been described: Caico (Rio Grande do Norte), the type-locality for T. b. brasiliensis; Petrolina (Pernambuco) for T. b. macromelasoma and Espinosa (Minas Gerais) for T. b. melanica. A fourth distinct chromatic pattern was found in Juazeiro (Bahia). A total of nine loci were studied. Values of Nei's genetic distance (D) were calculated. T. b. brasiliensis and T. b. macromelasoma are the closest populations with a D = 0.295. T. b. melanica had a D > or = 0.537 when compared to the others, a distance in the range of interspecific variation for other triatomine species. PMID- 9361738 TI - The infection rates of trypanosomes in squirrel monkeys at two sites in the Brazilian Amazon. AB - A study was conducted to determine the prevalence of natural infections by trypanosome species in squirrel monkeys: Saimiri sciureus (Linnaeus) and Saimiri ustus (Geoffroy) caught respectively near 2 hydroelectric plants: Balbina, in the State of Amazonas, and Samuel, in the State of Rondonia, Brazil. A total of 165 squirrel monkeys were examined by thick and thin blood smears (BS), haemocultures and xenodiagnosis: 112 monkeys, 67.9% (being 52.7% with mix infections) were positive to trypanosomes. Four species of trypanosomes were found in monkeys from the 2 areas: Trypanosoma (Tejeraia) rangeli Tejera or T. rangeli-like parasites in 58 squirrel monkeys (35.2%), Trypanosoma (Megatrypanum) minasense Chagas in 55 (33.3%), Trypanosoma (Herpetosoma) saimirii Rodhain or T. saimirii-like parasites in 53 (32.1%) and Trypanosoma (Schizotrypanum) cruzi Chagas in 17 (10.3%). As T. saimirii resembles T. minasense in blood-stream trypomastigotes and T. rangeli in cultural forms and in this survey almost all monkeys presenting trypanosomes morphologically indistinguishable from T. saimirii and/or T. minasense in BS were found through xenodiagnosis and/or haemoculture to be infected by T. rangeli, we suggest that the validity of T. saimirii needs to be evaluated. PMID- 9361739 TI - Analysis of Mycobacterium avium complex serovars isolated from AIDS patients from southeast Brazil. AB - The purpose of this study was to assess the distribution of Mycobacterium avium serovars isolated from AIDS patients in Sao Paulo and Rio de Janeiro. Ninety single site or multiple site isolates from 75 patients were examined. The most frequent serovars found were 8 (39.2%), 4 (21.4%) and 1 (10.7%). The frequency of mixed infections with serovar 8 or 4 was 37.8%. Among the 90 strains examined, M. intracellulare serovars (7 strains) and M. scrofulaceum (4 strains) were found in 11 isolates (12%) indicating that M. avium (88%) was the major opportunistic species in the M. avium complex isolates in Brazilian AIDS patients. PMID- 9361740 TI - Rickettsiae-infected ticks in an endemic area of spotted fever in the State of Minas Gerais, Brazil. AB - A study on tick-borne rickettsiosis was developed in the county of Santa Cruz do Escalvado, State of Minas Gerais, Brazil, where a clinical case of the disease, confirmed by necropsy, had been reported. Of the 1,254 ticks collected, 1,061 belonged to the Amblyomma genus, 57 to the Rhipicephalus sanguineus species, 81 to Boophilus microplus, and 46 to Anocentor nitens. The hemolymph test associated with Gimenez staining showed that 18 of the 221 A. cajennense specimens, 1 of the 16 R. sanguineus, 1 of the 22 B. microplus, 3 of the A. nitens, and 1 of the A. ovale contained rickettsia-like microorganisms. Only 3 A. cajennense ticks were positive under direct immunofluorescence. A. cajennense was the only species found on humans. PMID- 9361741 TI - Measurements of Trypanosoma evansi from the Pantanal. PMID- 9361742 TI - Anopheles aquasalis eggs from two Venezuelan localities compared by scanning electron microscopy. AB - Anopheles (Nyssorhynchus) aquasalis, is the main coastal vector of malaria from northeastern Venezuela to southeastern Brazil. Several authors have argued that An. aquasalis is a highly polymorphic species while others indicated that it is a complex of closely related species. This investigation compared the morphology of An. aquasalis eggs from Sinamaica (Zulia State) and Yaguaraparo (Sucre State), the west and east of Venezuela, respectively. We were able to separate eggs from the two localities using discriminant analyses based on ratios and percentages of anterior and posterior tubercles measured by scanning electron microscopy. The results of this work suggest that An. aquasalis has high intraspecific variation. PMID- 9361743 TI - First case of natural infection in pigs. Review of Trypanosoma cruzi reservoirs in Mexico. AB - An epidemiological research project was performed in the State of Morelos including collection of samples for blood smears and culture, serological tests, and xenodiagnoses from a total of 76 domestic and peridomestic mammals. Two strains of Trypanosoma cruzi were isolated by haemocultures; one from a pig (Sus scrofa), the first case of natural infection reported in Mexico, and the other from a dog (Canis familiaris). This study summarizes current information in Mexico concerning confirmed reservoirs of T. cruzi. PMID- 9361744 TI - Immune response to Trypanosoma cruzi shed acute phase antigen in children from an endemic area for Chagas' disease in Bolivia. AB - A field study of the immune response to the shed acute phase antigen (SAPA) of Trypanosoma cruzi was carried out in the locality of Mizque, Cochabamba department, Bolivia. Schoolchildren (266), with an average of 8.6 +/- 3.6 years, were surveyed for parasitological and serological diagnosis, as well as antibodies directed against SAPA using the corresponding recombinant protein in ELISA. The antibodies against SAPA were shown in 82% of patients presenting positive serological diagnosis (IgG specific antibodies). The positive and negative predictive values were 0.88. Antibodies anti-SAPA were shown in 80.8% of the chagasic patients in the initial stage of the infection (positive IgM serology and/or positive buffy coat (BC) test) and in 81.4% of the patients in the indeterminate stage of the infection (positive IgG serology with negative BC and IgM tests). These results show that the anti-SAPA response is not only present during the initial stage of the infection (few months) but extends some years after infection. PMID- 9361745 TI - Detection of Campylobacter jejuni invasion of HEp-2 cells by acridine orange crystal violet staining. PMID- 9361746 TI - Ultrastructural alterations induced by lithium chloride in DNA-containing organelles of a bat trypanosome. PMID- 9361747 TI - Comparative histopathology of Biomphalaria glabrata, B. tenagophila and B. straminea with variable degrees of resistance to Schistosoma mansoni miracidia. AB - A comparative histopathological study of three snails species--Biomphalaria glabrata, B. tenagophila and B. straminea--which had been infected with Schistosoma mansoni miracidia revealed similar qualitative features; consisting of areas of sporocyst proliferation and differentiation associated with reactive host reaction, at the time they were actively eliminating great number of cercariae. However, in specimens that were exposed to miracidia but failed to eliminate cercariae later on, different histopathological pictures were observed in different snail species. While B. glabrata exhibited frequent focal (granulomatous) proliferation of amebocytes in several organs, B. tenagophila and B. straminea only rarely showed such reactive changes, suggesting that the mechanism of resistance to miracidial infection probably follows different pathways in the snail species studied. PMID- 9361748 TI - Characterization of a Trypanosoma rangeli strain of Colombian origin. AB - A Colombian strain of Trypanosoma rangeli was characterized by analyzing its behaviour in different axenic and cellular culture, its infection rate and the histopathological lesions produced in experimental animals. Although slight inflammatory infiltrations were shown in different histopathological sections, no pseudocysts could be observed. Grace's insect medium is better than liver infusion tryptose or artificial triatomine urine supplemented with proline when studying T. rangeli metacyclogenesis, with a peak of 32% trypomastigotes. High infection rates were found in VERO and J774 cells. Because of its 100% infectivity rates and adequacy of parasitemia levels, C23 strain is a suitable model of T. rangeli biology study. PMID- 9361749 TI - Evaluation of popular stains for the diagnosis of American cutaneous leishmaniasis. PMID- 9361750 TI - Ultrastructure of endogenous stages of Eimeria ninakohlyakimovae Yakimoff & Rastegaieff, 1930 Emend. Levine, 1961 in experimentally infected goat. AB - The ultrastructure of endogenous stages of Eimeria ninakohlyakimovae was observed in epithelial cells of cecum and colon crypts from a goat experimentally infected with 2.0 x 10(5) oocysts/kg. The secondary meronts developed above the nucleus of the host cell. The nucleus first divides and merozoites then form on the surface of multinucleated meronts. Free merozoites in the parasitophorous vacuole present a conoid, double membrane, one pair of rhoptries, micronemes, micropore, anterior and posterior polar ring, a nucleus with a nucleolus and peripheral chromatin. The microgamonts are located below the nucleus of the host cell and contain several nuclei at the periphery of the parasite. The microgametes consist of a body, a nucleus, three flagella and mitochondria. The macrogamonts develop below the nucleus of the host cell and have a large nucleus with a prominent nucleolus. The macrogametes contain a nucleus, wall-forming bodies of type I and type II. The young oocysts present a wall containing two layers and a sporont. PMID- 9361751 TI - Artificial feeding of Amblyomma cajennense (Fabricius, 1787) (Acari:Ixodidae) through silicone membrane. AB - An artificial feeding system was used where citrated bovine blood was offered to male and female Amblyomma cajennense. Vestiges of blood, sweat, hair and exfoliated skin were used as phago-stimulants placed on the surface of the silicone membrane. The ticks were collected, as engorged nymphs, from naturally infested equines, with the ecdysis occurring in the laboratory. Four hundred ticks were used, 50% being female, at three to four weeks post-ecdysis. Vestiges of blood on the silicone membrane were the most efficient phago-stimulant and the association of vestiges of blood and sweat residue smears yielded better results compared to the other phago-stimulants used. PMID- 9361753 TI - Fecundity changes induced by low-doses of gamma radiation on Biomphalaria straminea (Dunker, 1848). AB - A population of 420 snails Biomphalaria straminea, an intermediate host of Schistosoma mansoni, received gamma-rays obtained from a 60Co source in low-doses (0/2,5/5/7,5/10/15/20 and 25 Gy); half population was kept in colonies (allowing cross fertilization) and the other half was maintained in sexual isolation (allowing self fertilization). Results showed that 15 Gy stimulates the fertility of both groups but the colonies were more sensitive and at this dose its fertility overpasses the control group dose. The possible hormonal role played in the observed phenomena is under investigation. PMID- 9361752 TI - [Development of Rhodnius pictipes Stal, 1872 fed on mice and through a silicone membrane (Hemiptera, Reduviidae, Triatominae)]. AB - Rhodnius pictipes (Hemiptera, Reduviidae) from Serra Norte, State of Para, Brazil, acclimatized in an insectary at the Laboratorio Nacional e Internacional de Referencia em Taxonomia de Triatomineos, Departamento de Entomologia, Instituto Oswaldo Cruz, were fed through a silicone membrane. In order to know the viability and the efficiency of this membrane compared with insects fed on mice, the number of bloodmeals taken, period of development of the five nymphal instars, longevity of adults, average amount of blood intake in each meal and percent of mortality were observed. A total of 310 insects, were used, comprising 50 nymphs of each instar, as well as 30 male and 30 female adults. Insects fed artificially had reduced minimal and maximal periods of development than the group fed on mice. The largest relative increase of body weight was observed in the 2nd instar followed by the 1st, and the amount of blood ingested increased during the development, to the 5th instar for both groups. There were no significant differences between the groups fed artificially and in vivo according to Tukey's test for p > 0.05. The percent of mortality in the 1st instar was 18% for artificially fed and 16% for the group fed on mice; these percentages decreased as insects developed until the 4th instar, without mortality, returning to increase in the 5th instar. R. pictipes was shown to be easily adaptable to artificial feeding, and could be considered as an important and viable experimental model. PMID- 9361754 TI - [Reproductive behavior of Synthesiomyia nudiseta van der Wulp (Diptera:Muscidae) under laboratory conditions]. PMID- 9361755 TI - Screening of Asteraceae (Compositae) plant extracts for larvicidal activity against Aedes fluviatilis (Diptera:Culicidae). AB - Ethanol extracts of 83 plants species belonging to the Asteraceae (Compositae) family, collected in the State of Minas Gerais, Brazil, were tested for larvicidal activity against the mosquito Aedes fluviatilis--Diptera: Culicidae). The extract from Tagetes minuta was the most active with a LC90 of 1.5 mg/l and LC50 of 1.0 mg/l. This plant has been the object of several studies by other groups and its active components have already been identified as thiophene derivatives, a class of compounds present in many Asteraceae species. The extract of Eclipta paniculata was also significantly active, with a LC90 of 17.2 mg/l and LC50 of 3.3 mg/l and no previous studies on its larvicidal activity or chemical composition could be found in the literature. Extracts of Achryrocline satureoides, Gnaphalium spicatum, Senecio brasiliensis, Trixis vauthieri, Tagetes patula and Vernonia ammophila were less active, killing more than 50% of the larvae only at the higher dose tested (100 mg/l). PMID- 9361756 TI - Efficacy of a new formulation of Bacillus sphaericus 2362 against Culex quinquefasciatus (Diptera:Culicidae) in Montes Claros, Minas Gerais, Brazil. PMID- 9361757 TI - Human reproduction. The missing parts of the puzzle. PMID- 9361758 TI - Human Y chromosome deletions in Yq11 and male fertility. AB - An overview is given about the current knowledge and research activities on the molecular analysis of interstitial deletions in the euchromatic part of the long arm of the human Y chromosome (Yq11). These mutations are associated with the male specific phenotype of azoospermia and severe oligozoospermia. The fact is stressed that only "de novo" microdeletions in Yq11 are of any diagnostic value in the infertility clinic because numerous polymorphic deletion events in Yq11 have also been reported. Three different "de novo" Yq11 microdeletions associated with male infertility are now found repeatedly (31 cases) in more than 700 patients. They strongly support the presence of at least three spermatogenesis loci in Yq11. They have been designated as AZFa, AZFb, and AZFc. Each of them should contain at least one Y gene functional in spermatogenesis and, if mutated, it should induce the same sterile phenotype as the corresponding AZF locus. These genes have not yet been found. However, some candidate genes exist: RBM for AZFb. DAZ and SPGY for AZFc. It is remarkable that all three encode testis specific RNA binding proteins with a similar sequence structure. Their structure and potential relationship is disussed. PMID- 9361759 TI - Frequency of Y-chromosome microdeletions (Yq11.22-23) in men with reduced sperm quality requesting assisted reproduction. PMID- 9361760 TI - Histone gene expression and chromatin structure during spermatogenesis. AB - The chromatin of male germ cells is restructured throughout spermatogenesis. Analysis of differential histone protein patterns at specific stages of spermatogenesis may contribute towards an understanding of the changes in chromatin structure and function during this differentiation process. The most striking changes in histone patterns occur at the stage of pachytene spermatocytes when most of the linker H1 histones are replaced by the testis specific subtype H1t. In addition, replacement of core histone subtypes is observed at this stage. These structural changes precede the reorganization of chromatin at haploid stages when histones are replaced first by transition proteins and then by protamines. PMID- 9361761 TI - Histone gene expression in the human testis. PMID- 9361762 TI - Endocrine control of germ cell proliferation in the primate testis. What do we really know? AB - The present chapter reviews current knowledge concerning hormonal regulation of gametogenesis in the primate testis. LH/testosterone and FSH are the prime regulators of primate spermatogenesis. Although either hormone is capable of stimulating all phases of the spermatogenic process including the formation of sperm, the combination of both hormones is necessary in most instances to achieve quantitatively normal germ cell numbers. Sertoli cell proliferation can also be induced by either hormone in juvenile monkeys. Evidence for differential effects of testosterone and FSH on gametogenesis, however, is lacking and a synergistic effect is observed when they are combined. Receptors for androgens and FSH occur exclusively on testicular somatic cells and, hence, the trophic effects of these hormones on germ cell numbers are indirect ones. Interestingly, both hormones seem to have a common target, the spermatogonial population but it is unknown how such an indirect albeit highly specific effect is mediated. Whether the trophic hormone action influences germ cell numbers via increased proliferation or decreased cell death or both remains to be seen. There is evidence to suggest that the local androgen requirements for primate spermatogenesis might be comparatively high. PMID- 9361763 TI - Quantification of somatic and spermatogenic cell proliferation in testes of ruminants. PMID- 9361764 TI - The immortalized mouse germ cell lines GC-1spg and GC-2spd as a model for mitochondrial differentiation during meiosis. PMID- 9361765 TI - A novel endozepine-like peptide (ELP) is exclusively expressed in male germ cells. PMID- 9361766 TI - Investigation on the proliferation of spermatogonia in normal and pathologic human seminiferous epithelium. PMID- 9361767 TI - Rapid method to detect CIS-cells. PMID- 9361768 TI - Testicular tumor cells pass through the epididymal ducts. PMID- 9361769 TI - AgNOR in human Leydig cell tumors. PMID- 9361770 TI - Endocrinological disturbances in germ cell tumour patients. Comparison of hormone levels and kinetics in peripheral and testicular vein blood. PMID- 9361771 TI - Reinvestigation of patients after primary therapy of testicular tumor. PMID- 9361772 TI - Carcinoma-in-situ in testes with germ cell tumour. Comparison of clinical parameters with histological findings in testicular tissue near to and distant from the tumour. PMID- 9361773 TI - Intratesticular sperm extraction. Basis for successful treatment of infertility in men with ejaculatory azoospermia. PMID- 9361774 TI - Molecular pathophysiology of the pituitary-gonadal axis. AB - Mutations of gonadotropin beta subunits or gonadotropin receptors are involved in some reproductive diseases leading to alterations of pubertal maturation or infertility. Homozygous inactivation of LH results in absence of pubertal maturation and hypogonadism in the male, whereas inactivation of FSH causes primary amenorrhea in females. Mutations of the gonadotropin receptors are classified into activating (the receptor is also active in the absence of the hormone: gain-of-function mutations) and inactivating types (the receptor is not properly processed and/or the hormone cannot bind: loss-of-function mutations). Activating mutations of the LH receptor have been described in familiar and sporadic forms of male-limited pseudoprecocious puberty, whereas they do not express any phenotype in females. The only activating mutation of the FSH receptor described to date was found in a hypophysectomized man who was fertile despite undetectable serum gonadotropin levels; the effects of constitutive FSH receptor activity occurring with normal pituitary function are not known. Homozygous inactivations of the LH and FSH receptor invariably lead to amenorrhea in genotypically female subjects. In males, inactivation of the LH receptor in its more severe form results in a clinical picture similar to the syndrome of complete androgen resistance, but milder forms of hypoandrogenization have been described as well. The clinical consequences of homozygous inactivation of the FSH receptor in males are associated with subfertility. Finally, polymorphic variants of both the gonadotropin LH and the FSH receptor are present in the normal population. PMID- 9361775 TI - Fetal and perinatal influence of xenoestrogens on testis gene expression. AB - The incidence of reproductive abnormalities in the male has been reported to have increased during the past 50 years. It has been suggested that these changes may be attributable to the presence of chemicals with oestrogenic activity in our environment. The aim of the experiments described in this chapter was to investigate the effects of acute exposure to high levels of xenoestrogens either indirectly during fetal life, or directly during neonatal life, on gene expression in the testis and pituitary. Fetal treatment involved administration of diethylstilbestrol (DES), 4-octylphenol (OP) or vehicle (oil, control) to pregnant rats on days 11.5 and 15.5 post coitum; fetuses were recovered on day 17.5. There was no difference between fetuses from control and treated mothers in either the overall histology of the testes or numbers of Leydig cells as determined by immunohistochemistry with an antibody directed against 3 beta-HSD. However there was a consistent and striking reduction in the amount of P450 17-a hydroxylase C17, 20 lyase (P450c17) and steroidogenic factor 1 (SF-1) detected by immunocytochemistry in testes from treatment groups given the higher doses of OP and DES. Oestrogen receptors (ER alpha) were present in the fetal leydig cells of all animals. Neonatal treatment involved direct injection of oil (control), DES, OP or Bisphenol A (Bis A) on days 2, 4, 6, 8, 10 and 12; pituitaries and testes were recovered on day 18. Testis weights and seminiferous tubule diameters were significantly reduced in animals treated with DES. In these same animals immunocytochemical localisation revealed that the amounts of FSH beta subunit and inhibin alpha subunit were reduced in their pituitaries and testes respectively. OP did not appear to have an acute, measurable effect on testis gene expression but a reduction in testis weight was noted in adult animals given the same treatment regime. The effects observed are consistent with negative feedback by oestrogens on pituitary production of FSH resulting in retarded maturation of seminiferous tubules and reduced Sertoli cell numbers. These studies have demonstrated that administration of high levels of oestrogens can affect gene expression in the testis early in life. However, the relevance of these findings to observations in man await a) a greater understanding of the physiological role(s) of oestrogens in normal males, b) an evaluation of the sources, routes of exposure, concentrations in vivo and bioavailability of xenoestrogens. PMID- 9361776 TI - Protease-protease inhibitor interactions in Sertoli cell-germ cell crosstalk. AB - Peritubular cells, Sertoli cells, and germ cells of the seminiferous tubule synthesize and secrete several proteases and protease inhibitors. Experimental evidence suggests that the complex network of proteolytic enzyme activity and their regulation by protease inhibitors play an important role in male reproduction. Interaction between protease and protease inhibitors seems to play an important role in remodeling and restructuring of the seminiferous tubule during spermatogenesis. Controlled proteolytic activity is also involved in the migration of germ cells from the basal compartment to the lumen of the seminiferous epithelium, and in the release of spermatids during spermiation. The recently reported occurrence of Sertoli cell membrane-associated proteases indicate the possible involvement of regulatory peptide systems within the testis. This view is supported by the detection of all components of one of these paracrine systems, the kallikrein-kinin system, in cells of the seminiferous tubule. PMID- 9361777 TI - New aspects of Leydig cell function. AB - Previous studies indicated that the Leydig cells of the human testes show similarities to neuroendocrine cells. In this context, the local synthesis of two neuroactive signaling molecules, namely nitric oxide (NO) and C-type natriuretic peptide (CNP), both acting via the second messenger, cyclic guanosine monophosphate (cGMP), might be of physiological relevance. By immunoblotting, immunohistochemical analyses and affinity crosslinking experiments, respectively, the presence of soluble guanylate cyclase (sGC), the NO receptor, and of guanylate cyclase B (GC-B), representing the CNP receptor, was demonstrated in Leydig cells, seminiferous tubules and blood vessels of the human testis. Moreover, cGMP and its binding protein cGMP-dependent protein kinase type I (GK I) were found in these structures. The functional activity of the two receptors was proved by generation of cGMP in response to treatments with the NO donor, sodium nitroprusside (SNP), and with CNP, respectively. As indicated by immunohistochemical analyses and by treatments of cells with either SNP or CNP, human Leydig tumour cells and MA10 cells, representing a mouse Leydig tumour cell line, were found to be distinguished by a reduced expression of the receptors for NO and CNP. Furthermore, expression levels of the components of the two cGMP generating systems were found to be widely unchanged in Leydig cells during different ontogenetic stages. Though cGMP has been shown to influence testosterone release, the constant developmental expression patterns of NO and CNP apparently independent of differences in androgen production, the down regulation of their receptors in tumorous cells, and the presence of GK I, may point to additional autocrine functions of these factors and of cGMP in Leydig cells. Moreover, possible paracrine actions of NO and CNP may include relaxation of seminiferous tubules and blood vessels in order to modulate sperm transport and testicular blood flow, respectively. These findings suggest that Leydig cell derived factors may exert activities different from or in addition to those involved in the regulation of testosterone production. PMID- 9361779 TI - Functional markers for fetal and postnatal differentiation of rat Leydig cells. PMID- 9361778 TI - Sertoli cell-specific gene expression in conditionally immortalized cell lines. PMID- 9361780 TI - Enzyme histochemical addition to morphological features of Leydig cells in senium. PMID- 9361781 TI - Differential display PCR cloning of W/Wv-mutant testis specific genes. PMID- 9361782 TI - Immunoreactivity for glial cell markers in the human testis. PMID- 9361783 TI - Insulin-like growth factor-binding protein (IGFBP)-5 in human testicular tubules. PMID- 9361784 TI - A novel role for atrial natriuretic peptide (ANP) in testis. PMID- 9361785 TI - Nerve growth factor (NGF) receptors in male reproductive organs. PMID- 9361786 TI - Delayed onset of spermatid elongation in the pubertal golden hamster testis depends on a developmental deficiency of Leydig cell-11 beta-HSD. PMID- 9361787 TI - Compartmentalization of the intertubular space in the human testis. PMID- 9361788 TI - Microcirculation and the vascular control of the testis. PMID- 9361789 TI - Expression of VEGF and its receptors and capillary density in Leydig cell tumors of the human testis. PMID- 9361790 TI - Angioarchitecture of the human spermatic cord. PMID- 9361791 TI - Morphological and functional aspects of the human spermatic cord veins. PMID- 9361792 TI - Semen analysis after treatment of varicocele by antegrade scrotal sclerotherapy. PMID- 9361793 TI - VEGF modulates the capillaries of the human epididymis. PMID- 9361794 TI - Endothelin-1 and its receptors in the human epididymis. PMID- 9361795 TI - The role of apocrine released proteins in the post-testicular regulation of human sperm function. AB - A unifying hypothesis is presented postulating an apocrine release of several seminal proteins which mix and reaggregate in seminal fluid, thereby eventually forming particles designated either as "prostasomes", "vesiculosomes" or "seminosomes". The term "aposomes" should be restricted to the blebs released from secretory cells in the rat dorsal prostate and coagulating gland. Three different proteins present in human seminosomes along with the respective antibodies have been used to identify the localization, function and hypothetical interaction with spermatozoa. The proteins were (1) seminal vesicle-derived fibronectin, (2) prostate-derived 5'-nucleotidase and (3) a hitherto unidentified 100 kD membrane protein from epididymis, seminal vesicle and prostate. I. Fibronectin is an extracellular matrix protein which is also secreted from the seminal vesicles participating in the formation of the seminal clot. Immunofluorescence and immunoelectron microscopy revealed a relatively broad distribution pattern of fibronectin immunoreactivity on spermatozoa from different donors. Adding a fibronectin antiserum at a moderate dilution to vital spermatozoa in vitro resulted in a significant increase in sperm motility. Purified plasma fibronectin added at various concentrations to a vital sperm preparation was found to inhibit sperm motility in a dose-dependent manner. Measurement of calcium fluxes in individual sperm in the presence of fibronectin showed a significant increase. These findings point to a possible post-testicular regulatory function of seminal fibronectin. 2.5'-Nucleotidase (5'-NT) is an enzyme that hydrolyzes nucleotides such as AMP or IMP into inorganic phosphate and the respective nucleoside. The highest amount and activity of 5'-nucleotidase was present in glandular cells of the prostate; much less was detected in seminal vesicles and epididymis. On spermatozoa, the enzyme was localized on the outer leaflet of the plasma membrane covering the acrosomal region. Addition of purified enzyme to an in vitro incubation system of spermatozoa had no effect on sperm motility. A slight reduction of overall motility, however, was observed after addition of 5'-NT antibody to the spermatozoa. When 5'-nucleotidase inhibitors and adenosine channel antagonists were added to the sperm incubation system, a clear-cut inhibition of sperm motility occurred in a dose-dependent manner. This result is interpreted as indicating a significant role of ecto-5' nucleotidase in the regulation of sperm motility. 3. A polyvalent antiserum against native human prostasomes recognized antigens in the range of 10-14 kD and of approximately 100 kD, respectively, in seminal fluid and prostate homogenates. Immunohistochemical studies revealed the presence of respective antigens in the epididymis, seminal vesicles and the prostate. Immunoelectron microscopy of ultracryo-sections showed labeling both of the apical plasma membrane in the prostate, as well as intraluminal secretory particles indicating the apocrine i.e. plasma-membrane bounded release of these particles. The secretory elements are termed "seminosomes". An affinity-purified fraction within the antiserum recognizes a 100 kD protein which is present both in the apical plasma membrane of the male genital glands, but also in the sperm head and principal piece of human spermatozoa. Incubation of spermatozoa with seminosomes and the respective purified antiserum had no effect on sperm motility. This is in contradistinction to former reports on motility increase induced by the so-called prostasomes. PMID- 9361796 TI - The molecular biology of the sperm surface. Post-testicular membrane remodelling. AB - The membrane of testicular spermatozoa undergoes extensive changes in the epididymis, including rearrangement, modification and loss of pre-existing components, addition of new glycoproteins from epididymal secretions, and exchange of lipid constituents. As a result, the membrane of cauda epididymidal spermatozoa has a different composition and different properties, which collectively contribute to male fertility. Special significance has been attributed to sperm surface structures that only appear post-testicularly in the epididymis, the so-called "maturation antigens". Therefore, human post-testicular proteins have been cloned by substractive screening of epididymal cDNA libraries, employing testis as the primary negative control. To date, there is scanty information on their function and mechanism of deposition on the sperm surface. However, the major maturation antigen CD52 seems to bind firmly to the sperm membrane via its GPI anchor. Its synthesis is carefully regulated by the cells of the epididymal epithelium, with temperature and androgens acting synergistically on CD52 mRNA levels. PMID- 9361797 TI - Purification and structural analysis of sperm CD52, a GPI-anchored membrane protein. PMID- 9361798 TI - Measurement of calcium in single human spermatozoa. PMID- 9361799 TI - Putative role of a serpin in modulation of acrosome reaction. PMID- 9361800 TI - Immunoelectron microscopic studies on outer dense fibres. PMID- 9361801 TI - The use of spin-labelled phospholipid analogues to characterize the transverse distribution of phospholipids and the activity of phospholipase-A2 in the cell membrane of bull spermatozoa. PMID- 9361802 TI - Interactions between leukocytes and the male reproductive system. The unanswered questions. PMID- 9361803 TI - Oxytocin and male reproductive function. AB - In the male mammal, the small peptide hormone oxytocin is produced in similar quantities within the hypothalamo-pituitary magnocellular system as in the female, yet for the male little is known about the physiology associated with this hormone. The present review summarizes what is known about the function of oxytocin in the male mammal and tries to take account of both central and systemic effects, and those linked with a local production of oxytocin within the male reproductive organs. In several species a pulse of systemic oxytocin, presumably of hypothalamic origin, appears to be associated with ejaculation. The systemic hormone could act peripherally stimulating smooth muscle cells of the male reproductive tract, but could also reflect central effects in the brain modulating sexual behaviour. In addition to systemic oxytocin, the peptide is also made locally within the testis, and possibly also the epididymis and prostate. In the former tissue it appears to have an autocrine/paracrine role modulating steroid metabolism, but may in addition be involved in contractility of the seminiferous tubules. However, the latter function may involve the mediacy of Sertoli cells which under some circumstances can also exhibit the components of a local oxytocin system. In the prostate of the rat and the dog oxytocin is linked again to steroid metabolism and may also act as a growth regulator. Finally, oxytocin in seminal fluid is discussed and its possible role in respect to the fate of the semen following ejaculation. PMID- 9361804 TI - Sensory innervation of the human penis. PMID- 9361805 TI - The uterine peristaltic pump. Normal and impeded sperm transport within the female genital tract. AB - Rapid as well as sustained sperm transport from the cervical canal to the isthmical part of the fallopian tube is provided by cervico-fundal uterine peristaltic contractions that can be visualized by vaginal sonography. The peristaltic contractions increase in frequency and presumably also in intensity as the proliferative phase progresses. As shown by placement of labeled albumin macrospheres of sperm size at the external cervical os and serial hysterosalpingoscintigraphy (HSSG) sperm reach, following their vaginal deposition, the uterine cavity within minutes. In the early follicular phase a large proportion of the macrospheres remains at the site of application, while a smaller proportion enters the uterine cavity with even a smaller one reaching the isthmical part of the tubes. In the mid-follicular phase of the cycle with increased frequency and intensity of the uterine contractions the proportion of macrospheres entering the uterine cavity as well as the tubes has significantly increased. In the late follicular phase with maximum frequency and intensity of uterine peristalsis the proportion of macrospheres entering the tube increases further at the expense of those at the site of application as well as within the uterine cavity. The transport of the macrospheres into the tube is preferentially directed into the tube ipsilateral to the dominant follicle, which becomes apparent in the mid-follicular phase as soon as a dominant follicle can be identified by ultrasound. Since the macrosphere are inert particles the directed sperm transport into the tube ipsilateral to the dominant follicle is not functionally related to a mechanism such as chemotaxis but is rather provided by uterine contraction of which the direction may be controlled by a specific myometrial architecture in combination with an asymmetric distribution of myometrial oestradiol receptors. Women with infertility and mostly mild endometriosis display on VSUP a uterine hyperperistalsis with nearly double the frequency of contractions during the early and mid- as well as midluteal phase in comparison to the fertile and healthy controls. During midcycle these women display a considerable uterine dysperistalsis in that the normally long and regular cervico-fundal contractions during this phase of the cycle have become more or less undirected and convulsive in character. Hyperperistalsis results in the transport of inert particles from the cervix into the tubes within minutes already during the early follicular phase, and may therefore constitute the mechanical cause for the development of endometriosis in that it transports detached endometrial cells and tissue fragments via the tubes into the peritoneal cavity. Moreover, dysperistalsis may contribute to the infertility in these patients since it results in a break down of sperm transport within the female genital tract. PMID- 9361806 TI - Egg-cumulus-oviduct interactions and fertilization. AB - In this communication we approach the events leading to fertilization in mammals by examining the triangle of egg, sperm and oviductal cell taking account of the local physiology and focussing on auto/paracrine interactions. The expression of growth factors and extra-cellular matrix (ECM)-components in bovine ovarian granulosa- and theca-cells, the oocyte-cumulus complex (OOC) and oviductal epithelium, as well as some of the corresponding secreted proteins can be detected through the estrous cycle. Components of the insulin-like (IGF), fibroblast (FGF) and transforming (TGF) growth factor systems, and also metalloproteinase 1 (MMP1) and urokinase (uPA) are found to be modulated in these cells prior to fertilization. Different expression levels between the cell types are found, each representative of a specific reaction window within that particular stage of the cycle. Our findings support the concept that most of the observed tissue in the reproductive tract is dependent upon on the effects of gonadotropins or steroids, but that the fine-regulation is conveyed by, for example, growth factors and ECM-components. We suggest a sophisticated, auto/paracrine and species-specific crosstalk of growth factors and ECM components between the different cell types involved, enabling fertilization and development of the embryo at the right time and in the right location. PMID- 9361807 TI - The cell biology of fertilization. AB - Research into the cell biology of mammalian fertilization has been stimulated by the desire to provide a theoretical framework for the development of novel approaches to contraception and the need to understand the cellular basis of human infertility. The results of such studies have revealed a complex cascade of interactions initiated by the contact between capacitated spermatozoa on the oocyte-cumulus complex and culminating in sperm-oocyte fusion. In this review we shall examine our current understanding of the fertilization process, highlighting the strategic importance of recent findings and key areas where information is lacking. PMID- 9361808 TI - The role of carbohydrates in sperm-egg interaction. PMID- 9361809 TI - X-ray crystallographic analysis of boar PSP-I/PSP-II complex. A zona pellucida binding protein. PMID- 9361810 TI - The zona pellucida "receptors". AB - Binding of mammalian sperm to the zona pellucida and the induction of the acrosome reaction are prerequisites for successful oocyte fertilization. In the mouse model, the zona pellucida consists of three sulfated glycoproteins, ZP1, ZP2, and ZP3. Zona pellucida proteins are secreted to form a filamentous zona matrix in which ZP2 and ZP3 complex into co-polymers cross-linked by ZP1. ZP3 is the ligand for primary sperm binding and important for the induction of the acrosome reaction. The zona pellucida glycoprotein ZP2 is also crucially involved in the process of fertilization. Previous reports suggest that ZP2 mediates secondary binding of spermatozoa and that cleavage of ZP2 by proteases released through cortical granule reaction causes zona "hardening" and thus prevents polyspermy. Human and mouse ZP2 proteins differ in the primary structure as derived from cDNA clones. We designed an immunological approach to search for ZP2 domains with functional relevance. Antisera were generated against synthetic peptides derived (a) from ZP2 amino acid sequences that are homologous in human and mouse ZP2 amino acid sequences (AS ZP2-20) or (b) from human ZP2 amino acid sequences that differ from the mouse ZP2 sequence (AS ZP2-26). Immunochemical studies with microbisected bovine zonae pellucidae demonstrated that both antisera, AS ZP2-20 and AS ZP2-26, specifically detected ZP2 protein. Using the competition-hemizona-assay, sperm binding to antibody treated bovine hemizonae pellucidae were compared with control hemizonae (given as hemizona index). Antiserum AS ZP2-20 significantly inhibited binding of spermatozoa to test hemizonae (p < 0.0001), whereas treatment of hemizonae with AS ZP2-26 did not influence sperm-egg interaction. Our results show that antibodies against ZP2 peptides react with bovine zonae pellucidae and can be used as markers for ZP2. Furthermore, AS ZP2-20 identifies a ZP2 epitope that is possibly of functional relevance for sperm-egg interaction. PMID- 9361811 TI - Fat and cancer. The epidemiologic evidence in perspective. PMID- 9361812 TI - Dietary lipids and the cancer cascade. PMID- 9361813 TI - Molecular studies on the role of dietary fat and cholesterol in breast cancer induction. PMID- 9361815 TI - Fatty acids and breast cancer cell proliferation. AB - We and others have shown that fatty acids are important regulators of breast cancer cell proliferation. In particular individual fatty acids specifically alter EGF-induced cell proliferation in very different ways. This regulation is mediated by an EGFR/G-protein signaling pathway. Understanding the molecular mechanisms of how this signaling pathway functions and how fatty acids regulate it will provide important information on the cellular and molecular basis for the association of dietary fat and cancer. Furthermore these in vitro studies may explain data previously obtained from in vivo animal studies and identify "good" as well as "bad" fatty acids with respect to the development of cancer. PMID- 9361814 TI - Fatty acid regulation of breast cancer cell growth and invasion. PMID- 9361816 TI - Lipoxygenase metabolites and cancer metastasis. PMID- 9361817 TI - Modulation of intracellular second messengers by dietary fat during colonic tumor development. AB - In conclusion, dietary n-3 polyunsaturated fatty acids found in fish oil are capable of suppressing carcinogen-induced ras activation in the colon prior to overt neoplasia. This in turn blocks the oncogene driven increase in colonic diacylglycerol mass, preventing the persistent activation and chronic down regulation of PKC isozymes, thereby maintaining tissue PKC levels. Since the maintenance of crypt PKC levels may sustain the homeostatic balance between cell proliferation, differentiation and apoptosis, the ability of dietary n-3 polyunsaturated fatty acids to block the carcinogen-induced decrease in steady state levels of colonic mucosal PKC may in part explain why these fatty acids protect against colon tumorigenesis. Additional studies are required in order to elucidate the mechanisms by which select dietary lipids reduce colonic tumor incidence. This research focus is absolutely essential, because if we do not know why a dietary component is protective or promotive of cancer, then we have no right to attempt to modify eating behaviors. PMID- 9361818 TI - Diet, apoptosis, and carcinogenesis. AB - It is known that long-term withdrawal of choline from the diet induces hepatocellular carcinomas in animal models in the absence of known carcinogens. We hypothesize that a choline deficient diet (CD) alters the balance of cell growth and cell death in hepatocytes and thus promotes the survival of clones of cells capable of malignant transformation. When grown in CD medium (5 microM or 0 microM choline) CWSV-1 rat hepatocytes immortalized with SV40 large T-antigen underwent p53-independent apoptosis (terminal dUTP end-labeling of fragmented DNA; laddering of DNA in agarose gel). CWSV-1 cells which were adapted to survive in 5 microM choline acquired resistance to CD-induced apoptosis and were able to form hepatocellular carcinomas in nude mice. These adapted CWSV-1 cells express higher amounts of both the 32 kDa membrane-bound and 6 kDa mature form of TGF alpha compared to cells made acutely CD. Control (70 microM choline) and adapted cells, but not acutely deficient hepatocytes, could be induced to undergo apoptosis by neutralization of secreted TGF alpha. Protein tyrosine phosphorylation is known to protect against apoptosis. We found decreased EGF receptor tyrosine phosphorylation in acutely choline deficient CWSV-1 cells. TGF beta 1 is an important growth-regulator in the liver. CWSV-1 cells express TGF beta 1 receptors and this peptide induced cell detachment and death in control and acutely deficient cells. Hepatocytes adapted to survive in low choline were also resistant to TGF beta 1, although TGF beta 1 receptors and protein could be detected in the cytoplasm of these cells. The non-essential nutrient choline is important in maintaining plasma membrane structure and function, and in intracellular signaling. Our results indicate that acute withdrawal of choline induces p53-independent programmed cell death in hepatocytes, whereas cells adapted to survive in low choline are resistant to this form of apoptosis, as well as to cell death induced by TGF beta 1. Our results also suggest that CD may induce alterations (mutations?) in growth factor signaling pathways which may enhance cell survival and malignant transformation. PMID- 9361819 TI - The role of peroxisome proliferator activated receptor alpha in peroxisome proliferation, physiological homeostasis, and chemical carcinogenesis. PMID- 9361820 TI - A hypothetical mechanism for fat-induced rodent hepatocarcinogenesis. PMID- 9361821 TI - Short chain fatty acid regulation of intestinal gene expression. PMID- 9361822 TI - Regulation of gene expression in adipose cells by polyunsaturated fatty acids. AB - In fat cells polyunsaturated fatty acids are both substrates for, and products of, triacylglycerol metabolism. Dietary fatty acids are efficiently incorporated into the triacylglycerol droplet under lipogenic conditions while rapidly mobilizing them during lipolytic stimulation. Hence, the flux and magnitude of the fatty acid pool in adipocytes is constantly changing in response to hormonal, metabolic and genetic determinants. Due to the rapidly changing flux of fatty acids, the majority of genes encoding enzymes and proteins of lipid metabolism are largely refractory to long-term regulatory control by fatty acids. Only at extremes of high or low lipid levels, or under pathophysiological conditions, do adipose genes respond by up- or down-regulating gene expression. Despite the lack of responsiveness to lipids in adipose tissue, a surprisingly large number of genes have been characterized recently as lipid responsive when assayed in heterologous systems. These observations suggest an endogenous negative element exists in the lipid signaling pathway in adipocytes. The major intracellular lipid binding protein in adipose cells is the adipocyte lipid binding protein (ALBP), the product of the aP2 gene. This protein is 15 kDa, abundant and found exclusively in the cytoplasm of adipocytes. The protein binds fatty acids and related lipids in a 1:1 stoichiometry within a large water filled interior cavity. The lipid binding protein forms high affinity associations with polyunsaturated fatty acids such as arachidonic acid (Kd approximately 250 nM) but not with prostaglandins of the E, D or J series (Kd > 4 microM). The upstream region of the aP2 gene contains a peroxisome-proliferator activated receptor response element which associates with PPARs to regulate its expression. A positive autoregulatory circuit exists to upregulate lipid binding protein expression when polyunsaturated fatty acid levels are increased. Analysis of adipose tissue from aP2 null animals generated by a targeted disruption revealed that the partial loss of ALBP expression in heterozygotes and complete lack of ALBP in the nulls was accompanied by a compensatory up-regulation of the keratinocyte lipid binding protein. However, the total amount of lipid binding protein in the nulls was less than 15% that in the wild type littermates. No evidence was found for upregulation of other lipid binding proteins such as the heart FABP or liver FABP. In aP2 nulls, the fatty acid composition was unaltered but the mass of fatty acid per gram tissue more than doubled relative to wild type. In heterozygotes, the level of fatty acid was intermediate to that of wild type and nulls, consistent with an intermediate level of lipid binding protein. These results indicate that the fatty acid pool level in adipocytes is inversely correlated with the amount of lipid binding protein. Since prostaglandin biosynthesis is dependent upon polyunsaturated fatty acid substrates, the intracellular lipid binding proteins control accessibility of substrates of the prostanoid pathway. Intracellular lipid binding proteins therefore are negative elements in polyunsaturated fatty acid control of gene expression. PMID- 9361823 TI - Regulation of peroxisomal fatty acyl-CoA oxidase in the yeast. Saccharomyces cerevisiae. AB - Peroxisomes are specialized organelles found in most eukaryote cells, where their major functions are in cellular respiration and fatty acid oxidation. Proliferation of this organelle, and induction of peroxisomal enzymes, is a phenomenon that occurs in diverse species, and is stimulated by a number of physiological and pharmacological stimuli. A large number of chemically diverse compounds, including hypolipidemic drugs and industrial plasticizers, have been shown to cause peroxisome proliferation and the induction of peroxisomal enzymes in rodents. Chronic exposure to these compounds produces hepatocellular carcinomas, however, the mechanism by which this tumorigenic event occurs is unknown. In the yeast Saccharomyces cerevisiae peroxisomes are induced when a fatty acid such as oleate is supplied as a carbon source in the growth medium. In addition, many peroxisomal enzymes are induced by growth on oleate; these include enzymes of the peroxisomal beta-oxidation cycle. This regulation occurs at the transcription level, and is controlled by specific trans-acting factors. The research in our laboratory has focused on the mechanisms involved in this regulation, and on the identification and characterization of the proteins involved. Our recent results, and current research directions are summarized. PMID- 9361824 TI - Dietary fat, genes, and human health. AB - These studies show that a macronutrient like dietary fat plays an important role in gene expression. In the cases presented here, dietary fat regulates gene expression leading to changes in carbohydrate and lipid metabolism. The interesting outcome of these studies is the finding that the molecular targets for dietary fat action did not converge with the principal targets for hormonal regulation of gene transcription, like hormone receptors. Instead, PUFA-RF targets elements that play key ancillary roles in gene transcription. This is important because it shows how PUFA can interfere with hormone regulation of a specific gene without having generalized effect on overall hormonal control, i.e. PUFA effects are promoter-specific. How PUFA-RF interferes with gene transcription will require the isolation and characterization of PUFA-RF along with the tissue-specific factors targeted by PUFA-RF. A different story emerges when fatty acids activate PPAR. Based on the studies presented here and elsewhere, long chain-highly unsaturated fatty acids (like 20:5,n-3 and 22:6, n 3) or high levels of fat activate PPAR. PPAR directly activates genes like AOX, but also inhibits transcription of genes like S14, FAS, apolipoprotein CIII, transferrin. For S14, the mechanism of inhibition involves sequestration of RXR, a critical factor for T3 receptor binding to DNA. Thus, PPAR can have generalized effects on T3 action or on other nuclear receptors, like vit. D (VDR) and retinoic acid (RAR) receptors, that require RXR for action. For apolipoprotein CIII and transferrin, PPAR/RXR heterodimers compete for HNF-4 binding sites (DR + 1). In addition to HNF-4, COUP-TF, ARP-1 and RXR all bind the DR + 1 type motif. These factors are important for tissue-specific regulation of gene transcription. PPAR can potentially interfere with the transcription of multiple genes through disruption of nuclear receptor signaling leading to changes in phenotype. Clearly, more studies are required to assess the role PPAR plays in the fatty acid regulation of gene transcription and its contribution to chronic disease. Finally, it is clear that dietary fat has the potential to affect gene expression through multiple pathways. Depending on the gene examined, PUFA might augment or abrogate gene transcription which leads to specific phenotypic changes altering metabolism, differentiation or cell growth. These effects can be beneficial to the organism, such as the n-3 PUFA-mediated suppression of serum triglycerides or detrimental, like the saturated and n-6 PUFA-mediated promotion of insulin resistance. How such effects contribute to the onset or progression of specific neoplasia is unclear. However, studies in metabolism might provide important clues for this connection. PMID- 9361825 TI - Nutritionally related disorders/diseases in Africans. Highlights of half a century of research with special reference to unexpected phenomena. PMID- 9361826 TI - The evolving epidemiology of fiber and heart disease. PMID- 9361827 TI - Dietary fibre and human cancer. Epidemiological data. PMID- 9361828 TI - What is a high fiber diet? AB - There is no recognized definition of what constitutes a high fiber diet. Intakes of dietary fiber in different populations internationally vary widely from less than 20 g to more than 80 g per day. The types of foods contributing fiber also vary; in some countries cereals contribute the most fiber, in others leafy or root vegetables predominate. Vegetables have the highest fiber content per Kcal, and in most populations with fiber intakes over 50 g, vegetables contribute over 50% of total fiber intake. In rural Uganda, where the fiber hypothesis was first developed by Burkitt and Trowell, vegetables contribute over 90% of fiber intake. An experimental diet, the "Simian" diet, has been developed to mimic as closely as possible using human foods, the diet consumed by our simian ancestors the great apes. It is also similar to the Ugandan diet in containing large amounts of vegetables and 50 g fiber/1000 Kcal. Though nutritionally adequate, this diet is very bulky and not a suitable model for general recommendations. Dietary guidelines are that fat intake should be < 30% of energy, with a fiber intake of 20-35 g/d. These recommendations are inconsistent with a high fiber diet because, for people consuming more than about 2400 Kcal, low fiber choices for fruits and grains must be selected to keep dietary fiber intake within the range of 20-35 g. In a 30% fat, 1800 Kcal omnivorous diet, selection of wholemeal bread and whole fruit, results in a fiber intake over 35 g/d, and for and 1800 Kcal vegetarian diet, with substitution of modest amounts of peanut butter and beans for meats, dietary fiber intake goes up to 45 g/d. Thus, if it is desirable to promote the use of unrefined foods, the recommended dietary fiber intake should be a minimum of 15-20 g/1000 Kcal. PMID- 9361829 TI - Overview on complex carbohydrates. PMID- 9361830 TI - Dietary guidelines and complex carbohydrates. PMID- 9361831 TI - Classification of complex carbohydrates. PMID- 9361832 TI - Determination of complex carbohydrates in foods as the sum of available starch and dietary fiber. PMID- 9361833 TI - Application of complex carbohydrates in the food industry. The consumer perspective. PMID- 9361834 TI - Soluble fiber and hypertension. PMID- 9361835 TI - Soluble fiber and energy regulation. Current knowledge and future directions. AB - Soluble dietary fiber is a potentially important factor determining our ability to maintain a stable energy balance and avoid obesity. However, clinical metabolic investigations have given conflicting results on the effects of soluble fiber on energy regulation, perhaps for the reasons that a) other dietary components that affect energy regulation have not always be controlled adequately and b) in the past it has been hard to ensure that subjects are consistently compliant with the dietary requirements of soluble fiber protocols. The recent development of techniques for assessing dietary compliance in metabolic studies, combined with increased control of non-fiber dietary variables that influence energy intake, should help ensure more consistent findings in future investigations. PMID- 9361836 TI - Soluble fibers and dietary lipids. PMID- 9361837 TI - Sites and mechanisms for the hypocholesterolemic actions of soluble dietary fiber sources. PMID- 9361838 TI - Butyrate and the colonocyte. Production, absorption, metabolism, and therapeutic implications. AB - Butyrate, a SCFA generated by microbial fermentation of dietary substrates, is produced in the colon of humans and may influence colonic disease. It is possible to manipulate the diet in order to enhance levels of butyrate in various regions of the large intestine. Butyrate is absorbed by colonocytes in the proximal colon via passive diffusion and by active transport mechanisms which are linked to various ion exchange transporters. In the distal colon, the main mechanism of absorption is passive diffusion of the lipid-soluble form. Butyrate and other SCFA are important for the absorption of electrolytes by the large intestine and may play a role in preventing certain types of diarrhea. The mechanism by which butyrate and other SCFA exerts control over fluid and electrolyte fluxes in the colon is not well delineated though it may occur through an energy generated fuel effect, the up-regulation of various electrolyte transport systems, as well as possible effects on neuroendocrine factors. Butyrate has been shown to have beneficial effects on some colonic pathologies. This SCFA may be protective against colorectal neoplasia. Butyrate regulates colonic motility, increases colonic blood flow and may enhance colonic anastomosis healing. Butyrate may reduce the symptoms from ulcerative colitis and diversion colitis and it may prevent the progression of colitis in general. Further investigations are needed to confirm these findings in controlled, randomized, double blinded clinical studies. PMID- 9361839 TI - Short chain fatty acids, intestinal adaptation, and nutrient utilization. PMID- 9361840 TI - Short chain fatty acids inhibit the expression of the neutrophil chemoattractant, interleukin 8, in the Caco-2 intestinal cell line. PMID- 9361841 TI - Short chain fatty acids. Production and effects on gut motility. PMID- 9361842 TI - Butyrate. Potential role in colon cancer prevention and treatment. PMID- 9361843 TI - Effect of short chain fatty acids on calcium absorption in humans. PMID- 9361844 TI - Influence of short chain fatty acids on intestinal growth and functions. PMID- 9361845 TI - Resistant starch--an update on its physiological effects. AB - Resistant starch (RS) has emerged as one of the main substrates for colonic fermentation, together with other undigestible polysaccharides and oligosaccharides. There are indications that RS may be a good source of butyrate, and that the rate and site of fermentation can be varied and optimized. This makes RS potentially important for colonic health, and production of food products containing RS challenging. The present RS content in most Western diets is probably low, but can be increased by foods high in RS. The physiological effects of RS are reviewed, as well as the formation of RS in foods and its analysis. PMID- 9361846 TI - Health benefits of non-digestible oligosaccharides. AB - Non-digestible oligosaccharides are complex carbohydrates of the non-a-glucan type which, because of the configuration of their osidic bonds, resist hydrolysis by salivary and intestinal digestive enzymes. In the colon they are fermented by anaerobic bacteria. Among the non-digestible oligosaccharides, the chicory fructooligosaccharides occupy a key position and, in most european countries, they are recognised as natural food ingredients. The other major products are the short chain fructooligosaccharides and galactooligosaccharides obtained by enzymatic synthesis using sucrose and lactose as substrates respectively, the soybean oligosaccharides, the xylooligosaccharides produced by partial hydrolysis of xylans and polydextrose or pyrodextrins prepared by a chemical treatment of carbohydrates. The most well known effect of most non-digestible oligosaccharides, and in particular of the fructooligosaccharides, is the selective stimulation of the growth of Bifidobacteria thus modifying significantly the composition of the colonic microbiota. Such a modification, which has clearly been demonstrated in human volunteers, is meant to be benificial in part because it is accompanied by a significant reduction in the number of bacteria reported to have pathogenic potential. Within the framework of research and development of "functional foods", such an effect justifies a "functional claim" for fructooligosaccharides namely "bifidogenesis". They are also typical "prebiotics". Besides their bifidogenic effect, the chicory fructooligosaccharides have additional nutritional properties on digestive physiological parameters like colonic pH and stool bulking which justify their classification as dietary fibers. Moreover, in experimental models, it has also been reported that they improve the bioavailability of essentiel minerals and that they reduce serum triglyceridemia by lowering hepatic lipogenesis. Such effects demonstrate interactions between the chicory fructooligosaccharides and key functions in the body but their significance for humans still need to be proven before being used to justify additional claims. PMID- 9361847 TI - Gastrointestinal effects of fructooligosaccharides. PMID- 9361848 TI - Phytosterols. PMID- 9361849 TI - Adding certain fiber-related nutrients to food products. PMID- 9361850 TI - Fiber and cancer protection--mechanisms. AB - There is no reason to believe that a single lumenal or tissue factor will hold the key to understanding the of dietary fiber's effect on reducing the risk of colon cancer. In fact, the data suggest that multiple, interacting factors will be revealed. After years of research, it appears that the bile acid hypothesis is not nearly as strong as first envisaged. Additionally, the theory that SCFA protect against colon cancer has little clinical or experimental support. There is no doubt that identification of genetic alterations, and their controlling factors, will play a major role in our understanding of this issue. The appeal of the original fiber hypothesis has not diminished but simply requires updating based on discoveries made since it was first proposed. It is this author's opinion that dietary fiber will likely be found to modulate human colon cancer and the mechanisms of its beneficial effect will probably be through multiple actions within the lumen and at the level of the target tissue. Based on our current knowledge of the pathogenesis of colon cancer we cannot make definitive statements about what percentage of colon cancer might be prevented by a specific type or amount of dietary fiber but it is reasonable to conclude that consumption of fiber-rich diets is associated with reduced risk of colon cancer. It is quite plausible that the combination of dietary fiber, or its metabolites, in conjunction with other phytochemicals may be necessary to realize inhibition of the tumorigenic process. PMID- 9361851 TI - Dietary fiber and bile acid metabolism--an update. PMID- 9361852 TI - Hard wheat bran and hard wheat bran fiber energy values measured in rats after 6 and 16 weeks. PMID- 9361853 TI - The protective role of dietary fiber in diverticular disease. PMID- 9361854 TI - Dietary guidelines/RDA/Daily Value workshop. PMID- 9361855 TI - Soluble dietary fiber workshop. PMID- 9361856 TI - Workshop report. Fiber and CHD management. PMID- 9361857 TI - Workshop on animal models used in fiber research. PMID- 9361858 TI - Personal mythology and psychotherapy: myth-making in psychological and spiritual development. AB - The sweeping changes and crises in the guiding myths of contemporary cultures provide the context of the individual's psychological and spiritual development. A five-stage process for facilitating the evolution of an individual's personal mythology is illustrated in a detailed case study, and the psychosocial tasks that must be accomplished to successfully navigate each stage are discussed. PMID- 9361859 TI - Women's mental health: some directions for research. AB - Some key issues regarding gender differences in the prevalence of mental disorders, the course of mental illness, and the use of services are reviewed, along with their diagnosis and psychopharmacologic treatment. Implications for clinical practice are examined, as are directions for future research that will ensure the presence of women's mental health as a major element in the national agenda on women's health. PMID- 9361860 TI - The regulatory status of center-based infant and toddler child care. AB - Ten years ago, a review of U.S. center-based infant and toddler care found that not even one state met federally recommended standards of quality with regard to group composition, staff training, and program of care. The present analysis indicates that little progress has been made since then. While most states currently require centers to follow appropriate practice guidelines, standards for staff training were rated as unacceptable in almost all states. Findings are discussed in terms of the interrelation of quality dimensions and the ongoing importance of improved state-level infant and toddler child-care regulation. PMID- 9361861 TI - Child welfare policy and practice: the myth of family preservation. AB - The family-preservation orientation of child welfare policy and practice is questioned, and the reasons why child rescue efforts continue to grow are explored. Child placement rates are examined in historical context and compared to those of other countries. This paper argues that the child welfare system in the U.S. has long been two "systems" and that, as currently structured, it is incapable of promoting family preservation. PMID- 9361862 TI - Evaluating systems of care for children: utility of the clinical case conference. AB - A clinical assessment of the Mental Health Services Program for Youth, a national initiative to integrate systems and coordinate care for severely emotionally disturbed children, was designed to augment and enrich the larger evaluation of program structure. Case conferences were used as a method of examining the effects of collaborative systems of care on vulnerable individuals and of generating clinical insight and understanding. Case vignettes are presented and discussed in terms of the contributions and shortcomings of current system-of care efforts. PMID- 9361863 TI - Transracial adoptees: developmental status after 17 years. AB - At the fifth phase of a longitudinal study of transracial adoption outcomes, 52 adolescents of black descent adopted in infancy were examined with respect to racial self-identity, general adjustment, and self-esteem. The 34 adolescents adopted into white families and the 18 adopted into black families identified themselves as black or of mixed race in similar proportions, and most were found to be well adjusted and to have good or very good self-esteem. The findings offer implications for adoption policy and placement decisions. PMID- 9361864 TI - Open adoption and adoptive mothers: attitudes toward birthmothers, adopted children, and parenting. AB - The nature and extent of contact between 238 adoptive mothers and their child's biological mother was assessed for the period prior to the birth of the child and during the first two years of the child's life. Adoptive mothers who reported such contact prior to the child's birth had significantly more favorable attitudes toward both the biological mother and the adopted child. Those with contact either before or after the birth also demonstrated significantly more favorable parenting attitudes. Policy implications and the need for further research are noted. PMID- 9361865 TI - Parental alcoholism and other family disruptions: adult outcomes among sisters. AB - Adult outcomes were investigated in 14 pairs of African-American and white daughters of alcoholic parents. On the basis of four outcome factors, subjects were divided into three sister-pair categories: well-adjusted, impaired, and mixed. Interviews and standardized questionnaires showed that family-of-origin variables contributing to the impaired adult outcomes included parental psychiatric problems and childhood abuse or neglect. PMID- 9361866 TI - Assessing resilience in adults with histories of childhood sexual abuse. AB - Adults with histories of childhood sexual abuse were categorized as being either resilient or nonresilient on the basis of current levels of depression and self esteem. Characteristics of both the individual and the early family environment distinguished resilient from nonresilient abuse survivors, as did the physically coercive nature of the abuse experience. PMID- 9361867 TI - Process and outcome in a hostel outreach program for homeless clients with severe mental illness. AB - A longitudinal study followed 55 homeless and severely mentally ill clients of a hostel outreach program to assess outcomes and their relationship to program elements. Results at 18-month follow-up indicated that, despite chronic histories of transiency and shelter use, housing stability had been achieved, and that initial gains in social functioning and symptom reduction had been increased. Development of a strong working alliance proved a key program element in the findings. PMID- 9361868 TI - Losing the housing game. The leveling effects of substance abuse. AB - Analysis of the housing dynamics and individual characteristics of a sample of 670 participants in the New Orleans Homeless Substance Abusers Program reveals substantial diversity with respect to income, education, and occupational attainment. Nevertheless, drug consumption and dependence serve as socioeconomic levelers, dissolving otherwise potentially critical differences in human-capital and economic capacities. The need to focus concurrently on both structural and individual causes of homelessness is emphasized. PMID- 9361869 TI - Homeless mentally ill veterans: race, service use, and treatment outcomes. AB - Comparisons of service use and treatment outcomes for 145 black and 236 white homeless veterans with mental disorders showed few differences. A greater improvement in psychiatric symptoms and alcohol problems among white than black veterans did not hold true when black veterans had participated in the residential treatment component of the program. The implications of the findings for the successful treatment of homeless black veterans are discussed. PMID- 9361870 TI - Post-traumatic stress disorder in child witnesses to domestic violence. AB - A sample of children aged 6-12, of whom 20 had witnessed domestic violence and and 15 had not, was examined for symptoms of post-traumatic stress disorder (PTSD), and witness status was found to be a significant predictor of PTSD. Implications for clinical intervention are discussed. PMID- 9361871 TI - Reciprocity in mother-infant vocal interactions: relationship to the quantity of mothers' vocal stimulation. AB - A study of 147 mother-infant dyads revealed that the most talkative mothers did not allow their infants to initiate many conversations. The least talkative mothers ignored many of their infants' vocalizations. Mothers in the mid-level talking range demonstrated the greatest reciprocity, allowing their infants to initiate more conversations. PMID- 9361872 TI - Trauma, dissociation, impulsivity, and self-mutilation among substance abuse patients. AB - Among 85 substance abusing or dependent inpatients, it was found that those with histories of distressing traumatic events reported more self-mutilative acts, higher levels of dissociation, and a greater degree of impulsivity than did patients without such histories. Implications of the findings for research and clinical practice are discussed. PMID- 9361873 TI - Enhancing self-esteem in a community mental health setting. AB - A group treatment program for enhancing self-esteem was examined in relation to outcomes for a mixed diagnostic group of mental health clients and for a comparison group of non-clients. Both groups reported satisfaction with the program and showed improvement on self-esteem scores from pretest to the posttest. The program proved practical in terms of implementation, evaluation, and member satisfaction. PMID- 9361875 TI - Scintigraphic biodistribution and plasma kinetics of indium 111-labeled transferrin in dogs. AB - OBJECTIVE: To determine plasma clearance kinetics and imaging biodistribution of indium 111-labeled transferrin (111In-TF) in dogs. ANIMALS: 7 adult dogs. PROCEDURE: After 30 minutes' incubation of 18.5 MBq (0.5 mCi) of 111InCl3 with 1 ml of serum (n = 3) or 1 ml of plasma (n = 4) at 37 C, dogs were given autologous 111In-TF i.v., and serial blood samples and right lateral and dorsal scintigraphic images were obtained immediately and 1, 3, 5, 9, 22, and 48 hours later. Blood and plasma clearance kinetics were determined from a least-squares, nonlinear fit of the sample radioactivity data. Blood radioactivity was compared with plasma radioactivity to determine the extent of cellular labeling. Imaging biodistribution was characterized by subjective and objective assessment of blood pool, liver, gastrointestinal (abdomen) tract, kidney, and bone marrow activity. RESULTS: 111In-TF plasma clearance was best described by a biexponential fit, with early and late clearance half-times of 6 and 49 hours, respectively. The 111In was not redistributed between transferrin (plasma proteins) and blood cells. Imaging studies documented progressive liver and bone marrow uptake of the 111In-TF over 48 hours. Some radioactivity was evident in the colon of 1 dog on 48-hour images. Decay-corrected count rates (counts/pixel/mCi/kg/min) within the abdominal region of interest increased over the 48-hour imaging period and exceeded the blood pool (cardiac) activity at 20 hours after injection. CONCLUSION: 111In-TF has a biexponential plasma clearance in clinically normal dogs, with early and late clearance half-time of 6 and 49 hours, respectively. Scintigraphically, 111In-TF localizes to sites of iron storage (bone marrow and liver) over time. Some loss of 111In-TF via the gastrointestinal tract may be seen on late 48-hour images. CLINICAL RELEVANCE: 111In-TF appears to be a viable radiopharmaceutical for use in dogs, with specific application for identifying those with protein-losing enteropathy. PMID- 9361874 TI - Reliability of using random urine samples for "spot" determination of fractional excretion of electrolytes in cats. AB - OBJECTIVE: To determine whether the "spot" method of determining fractional excretion (FE) of electrolytes in cats is accurate. ANIMALS: 5 clinically normal young adult female cats. PROCEDURE: Cats were acclimated to metabolism cages, and 2 consecutive 72-hour collections of urine were made to determine FE of total calcium, potassium, total magnesium, sodium, and phosphorus by conventional methods, using endogenous creatinine clearance as an estimate of glomerular filtration rate. During collections, small samples of urine were obtained by cystocentesis at 8 AM, 3 PM, and 9 PM for determination of FE of the electrolytes by use of the "spot" method. RESULTS: Values from "spot" determinations were highly variable, compared with 72-hour values, with a high percentage falling outside the range of mean +/- 2 SD for 72-hour FE values. CONCLUSIONS AND CLINICAL RELEVANCE: The "spot" method for determining FE is not precise, and if used, caution and judgement should be exercised in interpretation of the results. PMID- 9361876 TI - Use of carbamylated hemoglobin concentration to differentiate acute from chronic renal failure in dogs. AB - OBJECTIVE: To determine usefulness of carbamylated hemoglobin (CarHb) concentration for differentiation of acute renal failure (ARF) from chronic renal failure (CRF) in dogs. SAMPLE POPULATION: Samples from dogs with ARF or CRF and from nonazotemic control dogs. PROCEDURE: CarHb concentration was determined in heparinized blood samples by measuring the micrograms of valine hydantoin (VH) per gram of hemoglobin (Hb), using a high-performance liquid chromatography assay, in which carbamyl valine is converted to VH via acid hydrolysis. RESULTS: CarHb concentration was significantly higher in dogs with ARF and CRF, compared with values in control dogs (ARF vs control, P < 0.05; CRF vs control, P < 0.001). Furthermore, CarHb concentration was significantly (P < 0.001) higher in dogs with CRF, compared with that in dogs with ARF. Carbamylated hemoglobin concentration did not correlate with serum urea nitrogen or creatinine concentration. Using a cutoff value of 100 micrograms of VH/g of Hb, the sensitivity and specificity of CarHb concentration for differentiating ARF from CRF was 96.1 and 84.2%, respectively. CONCLUSIONS: CarHb concentration was useful in the differentiation of ARF from CRF in the dogs of this study. CLINICAL RELEVANCE: CarHb concentration may be used to increase the accuracy of identifying ARF, so that early, aggressive management can be instituted, thereby increasing the chance of recovery. PMID- 9361877 TI - Urine N-acetyl-beta-D-glucosaminidase activity in healthy cattle. AB - OBJECTIVE: To measure urine N-acetyl-beta-D-glucosaminidase (NAG) activity of healthy cattle, using 3 substrates (4-methylumbelliferyl-N-acetyl-beta-D glucosaminide, sodio-m-cresolsulfonphthaleinyl-N-acetyl-beta-D-glucosaminid e, and p-nitrophenyl-N-acetyl-beta-D-glucosaminide), and to determine the relations between the obtained values and age and sex of cattle. ANIMALS: 50 healthy lactating Holstein-Friesian cows and 10 healthy Holstein-Friesian steers. PROCEDURE: Untimed urine samples were collected, and urine NAG activity was measured, using the 3 aforementioned methods. Urine creatinine concentration also was measured, and NAG activity was expressed as units per gram of creatinine (NAG index). Correlations between urine NAG activity and age and sex of cattle were investigated. Furthermore, correlations among data obtained by each of the 3 methods were determined. RESULTS: Urine NAG activity in cows measured by each of the 3 methods was < 3.0 U/L. Urine NAG activity in steers was significantly higher than that in cows. However, there was no significant difference between the sexes in NAG index. There were no significant differences in mean values of NAG activity and index among cows of various age groups. Individual values of urine NAG activity determined by each method correlated significantly with each other. CONCLUSIONS AND CLINICAL RELEVANCE: Urine NAG activity and NAG index of healthy cattle will be useful for determining diagnostic criteria of renal disease in cattle. PMID- 9361878 TI - Development of an automated turbidimetric immunoassay for quantification of bovine serum immunoglobulin G. AB - OBJECTIVE: To develop an automated turbidimetric immunoassay (TIA) for measurement of bovine IgG. SAMPLE POPULATION: 24 bovine serum samples. PROCEDURE: IgG concentration was determined by use of the TIA, and results were compared with those of the radial immunodiffusion (RID) method. Variables were determined, using commercially available reagents and a clinical biochemical analyzer. For the TIA, polyclonal goat anti-bovine IgG (Fc specific) serum, bovine IgG calibrator serum, and polyethylene glycol reaction buffer were used. Sample concentrations were determined by the instrument, using the linear regression method of least squares. The accuracy of this assay was validated by referencing to a purified bovine IgG standard and by recovery of control standards. Parallelism was documented by assay linearity and serial sample dilution linearity. Interference resulting from hemolyzed samples was examined. RESULTS: The TIA method correlated positively (r = 0.9957) and significantly (P < 0.05) with the RID method, yielding a regression equation with slope of 0.78708 and y intercept of 1.02102. Bias attributable to hemolysis was not observed. CONCLUSIONS: The TIA method is automated, accurate, and precise for bovine serum IgG quantification. CLINICAL RELEVANCE: This assay provides sample results in approximately 10 minutes and may be used as an alternative to the manual RID method. PMID- 9361879 TI - Effects of selection and habituation on vertical ground reaction force in greyhounds. AB - OBJECTIVE: To determine effect of dog selection and habituation on vertical ground reaction force variables. ANIMALS: 133 Greyhounds of either sex, weighing between 22 and 39 kg. PROCEDURE: Vertical ground reaction force variables (peak [PFz] and impulse [IFz]) for hind limbs were studied in dogs at 3 levels of habituation. Dogs of group 1 (n = 81) did not have prior experience with the gait analysis routine. Group-2 dogs (n = 52) were selected for having an amiable disposition, and were first evaluated after participating in an intermediate habituation routine (group 2a). These dogs were reevaluated after undergoing the full habituation routine (group 2b). RESULTS: 3 of the ground reaction force variable differed significantly between dogs of groups 1 and 2 (a and b). Dogs that had not been habituated to the gait analysis routine (group 1) had significantly longer stance times than did dogs that had been more carefully selected and habituated. Intradog coefficients of variation for PFz and the IFz were significantly greater in group-1 dogs. The PFz for group-2a dogs was significantly greater than that for group-1 dogs. Differences identified between groups 2a and 2b were more likely to be attributed to habituation only. These included significantly shorter stance time and lower intradog coefficient of variation for IFz in dogs having the highest level of habituation. CONCLUSION: Selection and habituation have measurable effects on vertical ground reaction force data obtained from trotting dogs. These include significantly shorter hind limb stance times, lower impulses of vertical force, with smaller coefficients of variation for peaks and impulses of vertical force within dogs. CLINICAL RELEVANCE: In controlled studies where critical decision making is based on gait analysis data, careful selection of subjects and habituation will significantly improve precision of the data and has the potential to reduce the subject or repetition sample size. PMID- 9361880 TI - Prevalence, vasculature, and innervation of myocardial bridges in dogs. AB - OBJECTIVE: To report gross anatomic examination of the canine myocardial bridge (MB), a muscular band found above the coronary artery (CA), with respect to its occurrence, location, vascularization, and innervation. SAMPLE POPULATION: 629 canine hearts obtained within 1 to 3 hours after euthanasia. PROCEDURE: After an incision was made at the left fifth intercostal space, the pericardial sac was cut open, and if an MB was present, the heart, lungs, and annexed structures were removed together and subsequently subjected to macroscopic examination of MB musculature and innervation after formalin fixation. Vascular casting was performed by use of methyl methacrylate perfusion. RESULTS: Of the 629 canine hearts examined, 189 (30%) had MB, occurrence of which was independent of sex, age, and breed. Among 13 MB-containing specimens examined in detail, there was great variation in thickness (0.11 to 2.24 mm; mean, 0.45 mm) of MB and distance (24 to 236 microns; mean, 103 microns) between the MB and the paraconal interventricular branch of the left CA (PIBL). One pair or 2 pairs of blood vessels from the PIBL supplied the MB muscle. Venous blood returned to the coronary circulation via the branches of the great coronary vein coursing on both sides of the PIBL, in close contact with the PIBL and the groove wall. The 2 veins rejoined at the upper portion of the PIBL and passed obliquely to the coronary groove under the left auricle, and finally drained the blood through the coronary sinus into the right ventricle. Innervation to the MB muscle was derived from nerve branches of the middle cervical ganglion and left vagus nerve. CONCLUSION: Prevalence and localization of MB in dogs and human beings are similar. Vascularization of the MB muscle originates from the PIBL. The cervical ganglion and vagus nerve control the MB muscle. PMID- 9361881 TI - Evaluation of aspartate transaminase activity and beta-hydroxybutyrate concentration in blood as tests for prediction of left displaced abomasum in dairy cows. AB - OBJECTIVE: To evaluate aspartate transaminase (AST) activity and beta hydroxybutyrate (BHB) concentration in blood obtained during the first or second postpartum (PP) week as tests for prediction of subsequent left displaced abomasum (LDA) diagnosis in dairy cows. ANIMALS: 36 cows with LDA tested at a mean 3 PP days, which was 7 to 22 days prior to LDA diagnosis (25, 75% quantiles), and 28 cows with LDA tested at 10 PP days, which was 5 to 18 days prior to LDA diagnosis, were matched to 3 controls per case by herd and calving date. Data were available from a large field study. PROCEDURE: Odds ratio, sensitivity, specificity, and likelihood ratio were determined for various AST and BHB cutoff values. RESULTS: AST, using cutoff values between 100 and 180 U/L, and BHB, using cutoff values between 1,000 and 1,600 mumol/L, were significantly associated with subsequent LDA diagnosis. When cutoff values were increased, odds ratio and likelihood ratio increased; however, sensitivity decreased and specificity increased. CONCLUSION AND CLINICAL RELEVANCE: AST activity and BHB concentration in blood obtained during the first or second PP week might be useful as predictors of subsequent LDA diagnosis. PMID- 9361882 TI - Clinical, morphologic, and biochemical characteristics of Chediak-Higashi syndrome in fifty-six Japanese black cattle. AB - OBJECTIVE: To characterize Chediak-Higashi syndrome (C-HS) in Japanese Black cattle. ANIMALS: 56 of 200 cattle with a bleeding disorder and giant granules in leukocytes. PROCEDURE: Clinical observation, CBC, hemostatic screening test, platelet aggregometry, electron microscopy, platelet constituent analysis, and ophthalmoscopic examination were done. RESULTS: Affected Japanese Black cattle had increased bleeding tendency and abnormal granules in their leukocytes. Susceptibility to infection was not increased. Cutaneous albinism was evident in 6 new-born calves, but not in most affected cattle. In all affected cattle, the tapetal fundus was pale and the nontapetal fundus was almost devoid of pigment. By electron microscopy, a remarkable decrease in the number of dense granules in platelets was observed. Functionally, collagen-induced platelet aggregation was markedly reduced. CONCLUSIONS: This bleeding disorder was diagnosed as C-HS. With regard to susceptibility to infection, albinism, and mortality, clinical manifestations of C-HS in Japanese Black cattle were moderate, compared with C-HS in human beings and Hereford cattle. CLINICAL RELEVANCE: Because an autosomal recessive mode of inheritance was documented and recessive homozygotes could be easily detected, C-HS in Japanese Black cattle can be controlled. PMID- 9361883 TI - Effects of Pasteurella haemolytica leukotoxin and lipopolysaccharide on histamine, prostanoid, and leukotriene release by bovine lung parenchyma in vitro. AB - OBJECTIVE: To identify the effect of Pasteurella haemolytica lipopolysaccharide (LPS) and leukotoxin (LKT) on spontaneous and calcium ionophore-induced histamine and inflammatory mediator release from isolated bovine lung parenchyma. SAMPLE POPULATION: Lungs from 8 healthy cattle. PROCEDURE: Isolated bovine lung parenchyma was incubated in vitro for 2 hours with LKT or LPS, and spontaneous and induced release of inflammatory mediators was determined. RESULTS: LKT and LPS increased spontaneous release of histamine and leukotriene B4. In addition, incubation with LPS increased spontaneous release of prostaglandin E2. Moreover, a differential effect of the 2 toxins on calcium ionophore-induced inflammatory mediator release was observed. LKT specifically primed isolated lung parenchyma to release leukotriene B4 and thromboxane B2 in response to calcium ionophore, whereas LPS did not alter the profile of prostanoids released by bovine lung tissue exposed to calcium ionophore. CONCLUSIONS: Pasteurella haemolytica toxins have a direct effect on bovine lung parenchyma, causing release of inflammatory mediators, which contribute to response to infection. Furthermore, bacterial toxins (LKT in this study) may sensitize tissues to the effects of other irritant stimuli, amplifying the inflammatory response. PMID- 9361884 TI - Nucleic acid amplification for rapid detection of Rhodococcus equi in equine blood and tracheal wash fluids. AB - OBJECTIVE: To evaluate the ability of nucleic acid amplification techniques to detect Rhodococcus equi in equine buffy coat, blood, and tracheal wash fluid and to differentiate between virulent and avirulent strains of the bacteria. SAMPLE POPULATION: Blood anticoagulated with EDTA and tracheal wash fluid from healthy horses. PROCEDURE: Logarithmic dilutions of virulent and avirulent strains of R equi were added to equine buffy coat and tracheal wash fluid samples. The DNA was extracted and amplified by polymerase chain reaction (PCR), using primers specific for the 16S ribosomal subunit gene and the virulence plasmid of R equi. RESULTS: PCR with 16S ribosomal subunit primers amplified a 441-bp segment of DNA from virulent and avirulent strains of R equi, but not from samples containing other species of bacteria. The virulence plasmid primers amplified an 875-bp segment of DNA from virulent strains of R equi, but not from avirulent R equi, or from other species of bacteria. Virulent strains of R equi could be identified by PCR and differentiated from avirulent strains within 12 to 24 hours after sample collection, with as few as 10 to 100 organisms present. CONCLUSIONS: PCR can be used to rapidly and accurately identify R equi in equine blood and tracheal wash fluid samples and can differentiate between virulent and avirulent strains of the organism. CLINICAL RELEVANCE: Because PCR can confirm a diagnosis of R equi infection in horses more rapidly and specifically than use of standard culture techniques, extrapolation of this assay to soil and fecal samples could be useful in epidemiologic studies and studies of environmental disinfection or decontamination. PMID- 9361885 TI - Influence of a blend of fructo-oligosaccharides and sugar beet fiber on nutrient digestibility and plasma metabolite concentrations in healthy beagles. AB - OBJECTIVE: To evaluate effects of a blend of fructo-oligosaccharides and sugar beet fiber (4:1) at 3 incorporation rates on nutrient digestibility and plasma glucose, insulin, alpha-aminonitrogen, urea, cholesterol, and triglycerides concentrations measured weekly in nonfed dogs and during a 360-minute period after a meal. ANIMALS: 8 castrated 1- to 1.4-year-old young adult male Beagles weighing 10.0 to 13.5 kg. PROCEDURE: Diets containing 2 incorporation rates of a blend of fructo-oligosaccharides and sugar beet fiber (5 and 10% on a dry matter basis [diets B and C, respectively]) were compared with a control diet without additional fiber (diet A). The 3 diets were evaluated for ability to modify digestibility of dry and organic matter, protein, fat, and ash and for effects on plasma glucose, insulin, alpha-aminonitrogen, urea, cholesterol, and triglycerides concentrations. Each diet was fed for 6 weeks; plasma samples were collected weekly before feeding and after feeding on the last day of the period. During 1 week at the end of the 6-week period, dogs were kept in metabolic cages. Each period of the block was followed by a 4-week washout period. RESULTS: Incorporating the blend of fructo-oligosaccharides and sugar beet fiber in the diet was associated with greater passage of wet feces (diets B and C) and lower protein digestibility (diet C). Postprandial glucose (diet C), urea (diets B and C) and triglyceride (diets B and C) concentrations were significantly (P < 0.01) decreased. Weekly preprandial measurements were characterized by decreased urea (diets B and C), cholesterol (diet C), and triglycerides (diets B and C) concentrations (P < 0.001). CONCLUSION: Chronic consumption of fermentable fiber is associated with mildly decreased protein digestibility and with metabolic effects in nonfed or fed dogs. CLINICAL RELEVANCE: A blend of fructo oligosaccharides and sugar beet fiber should be tested as a dietary aid for treatment of chronic diseases, such as diabetes mellitus or hyperlipidemia, in dogs. PMID- 9361886 TI - Effects of various feeding regimens on the energy balance of equine neonates. AB - OBJECTIVE: To determine the effect of diet on energy intake, loss, and metabolism in foals 2 to 7 days old. ANIMALS: 14 pony foals. PROCEDURE: Group-A foals suckled their dams, group-B foals were fed milk replacer, and group-C foals were fed by total parenteral nutrition (TPN). Energy balance studies were performed over 8-hour periods on postpartum days 2, 4, and 7. RESULTS: Mean gross energy (GE) intake of group-A foals increased between days 2 and 7. Approximately 3% of GE was excreted in urine and feces, and energy expenditure remained constant. These foals were in positive energy balance, and mean body weight increased. From day 4 onward, group-B foals consumed more energy than did group-A foals because the milk replacer had a higher energy content than did mares' milk. Mean energy loss in group-B foals was 14% of GE on day 2, but this value decreased subsequently. Energy expenditure in group-B foals was less than that in group-A foals, and energy balance was positive. Group-C foals had the lowest energy intake and expenditure; energy balance was negative on postpartum day 2. These foals also had gastrointestinal tract problems. CONCLUSIONS: Mares' milk is highly digestible and is correlated with positive energy balance in neonatal foals. Milk replacer initially is less digestible than mares' milk. In this study, TPN was associated with negative energy balance. CLINICAL RELEVANCE: The data indicate the advantages of enteral feeding with mares' milk and highlight the clinical and technical difficulties associated with TPN. PMID- 9361887 TI - Effect of postexercise carbohydrate supplementation on muscle glycogen repletion in trained sled dogs. AB - OBJECTIVE: To evaluate the effect of immediate postexercise carbohydrate supplementation on muscle glycogen (MG) repletion during the first 4 hours of recovery in sled dogs. ANIMALS: 24 Alaskan Huskies. PROCEDURE: Dogs were assigned to 1 of 3 treatment groups, and a muscle biopsy specimen was obtained 1 hour before and immediately (group A) or 4 hours (groups B and C) after a 30-km run. Immediately after exercise, dogs in group A and group C were given water; dogs in group B were given a glucose polymer solution (1.5 g/kg of body weight) in water. RESULTS: At 4 hours after exercise, MG concentration was significantly greater in group-B than in group-C dogs; the value in group-C dogs was not different from the value in group-A dogs immediately after exercise. Assuming similar rates of glycogen depletion between treatment groups, during the first 4 hours of recovery, group-B dogs replaced 49% of the glycogen used during exercise. Plasma glucose concentration was significantly greater in group-B than in group-A and group-C dogs at 100 minutes after exercise. CONCLUSIONS: Immediate postexercise carbohydrate supplementation in sled dogs leads to increased glucose concentration, which in turn promotes more rapid rate of MG repletion in the first 4 hours of recovery than is observed in dogs not given supplements. CLINICAL RELEVANCE: For dogs running in multiple heats on a single day or over several consecutive days, immediate postexercise carbohydrate supplementation may promote more rapid and complete recovery between bouts of exercise. PMID- 9361888 TI - Efficacy of eprinomectin against mange mites in cattle. AB - OBJECTIVE: To determine whether eprinomectin was effective against mange caused by Chorioptes bovis and Sarcoptes bovis in cattle. ANIMALS: 80 cows naturally infested with C bovis and 30 cattle experimentally infested with S bovis. PROCEDURE: 6 trials were performed to determine efficacy against C bovis, and 2 trials were performed to determine efficacy against S bovis. In each trial, a group of untreated animals or of animals treated with vehicle alone was compared with a group of animals treated with a 0.5% formulation of eprinomectin applied topically (500 micrograms/kg). Number of mites in skin scrapings was determined prior to treatment and at weekly intervals for 8 weeks after treatment. Severity of skin lesions was evaluated when skin scrapings were obtained. In 5 trials, animals were weighed before and 56 days after treatment. RESULTS: Mite counts for treated cattle were significantly less than counts for control cattle from day 14 onwards in trials to determine efficacy against C bovis and from day 7 onwards in trials to determine efficacy against S bovis. Mites were not detected in scrapings collected from treated cattle on day 56. Mean weight gain of treated cattle was not significantly different from mean weight gain of control cattle in trials evaluating efficacy against C bovis but was significantly greater in trials evaluating efficacy against S bovis. CONCLUSION AND CLINICAL RELEVANCE: Eprinomectin was highly effective against C bovis and S bovis. Because eprinomectin can be administered to lactating cows, it may be useful for controlling mange in cattle. PMID- 9361889 TI - Comparison of flea control strategies using imidacloprid or lufenuron on cats in a controlled simulated home environment. AB - OBJECTIVE: To compare the effect of monthly treatments with imidacloprid (an adulticide) or lufenuron (an insect development inhibitor) for protecting cats against Ctenocephalides felis felis in a simulated home environment. ANIMALS: 3 matched groups of 4 cats each. PROCEDURE: A self-propagating flea life cycle continuously exposing cats to 'natural' infestation was established in 3 pens. Small artificial infestations were later superimposed to mimic the effect of a cat roaming outdoors and acquiring extraneous fleas. One pen housed an untreated control group, and the other 2 pens housed cats treated every 28th day with an imidacloprid spot-on formulation or lufenuron suspension, respectively. Flea counts were performed at 14-day intervals for 112 days. RESULTS: Flea numbers increased on control cats around day 42 when mean counts on cats in the imidacloprid and lufenuron groups decreased by 100 and 86.8 percent, respectively. Fleas were not found on any imidacloprid-treated cat, but lufenuron treated cats were consistently parasitized. CONCLUSIONS: Imidacloprid administered at monthly intervals maintained flea burdens below the limit of detection, whereas clinically important flea populations developed in the lufenuron treatment pen. CLINICAL RELEVANCE: Results from this experimental model suggest that flea populations within a home may be controlled by carefully timed on-host treatments with potent long-acting insecticides such as imidacloprid. PMID- 9361891 TI - Cardiovascular effects of equipotent isoflurane and alfentanil/isoflurane minimum alveolar concentration multiple in cats. AB - OBJECTIVE: To determine whether administration of opioids to anesthetized cats induced less cardiovascular depression than that induced by an equivalent amount of anesthetic alone, and to measure endocrine responses to a noxious stimulus. ANIMALS: 6 healthy female cats. PROCEDURE: Anesthesia was induced with isoflurane and was maintained for 60 minutes at 1.3 isoflurane MAC. Blood gas tensions, pH, and plasma alfentanil and hormone concentrations, blood pressures, and cardiac output were measured. A noxious stimulus was applied for 5 minutes, while blood acquisition and measurements were repeated. Alfentanil was administered i.v. to achieve estimated plasma concentration of 500 ng/ml, and end-tidal isoflurane concentration was reduced by 35%. After another 60 minutes, blood was obtained and measurements were taken, then a second 5-minute noxious stimulus was applied while blood acquisition and measurements were retaken. RESULTS: Alfentanil administration and reduction of isoflurane concentration significantly increased body temperature, heart rate, mean arterial pressure, mean pulmonary arterial pressure, stroke index, cardiac index, hemoglobin, oxygen delivery index, PvO2 and PvCO2, dopamine, epinephrine (EPI), norepinephrine (NOREPI), and cortisol values, and significantly decreased arterial and venous pH. Application of a noxious stimulus significantly increased heart rate, stroke index, cardiac index, PaO2, oxygen delivery index, arterial and venous pH, and NOREPI values, and decreased bicarbonate, PaCO2, PvCO2, and EPI values. Alfentanil administration blunted cardiac index, PaCO2, oxygen delivery index, arterial pH, PaO2, and EPI, and NOREPI responses to a noxious stimulus. CONCLUSIONS: Compared with isoflurane alone, alfentanil administration and reduction of isoflurane MAC improved cardiovascular variables, and blunted respiratory, hormonal, and most hemodynamic responses to a noxious stimulus in cats. CLINICAL RELEVANCE: Use of the balanced opioid anesthesia regimen induced some beneficial effects in healthy cats; effects were similar to, although greater in nature, than effects induced by a noxious stimulus. PMID- 9361890 TI - Pharmacokinetics of luxabendazole after oral and intravenous administration to sheep. AB - OBJECTIVE: To determine pharmacokinetics of luxabendazole after oral and i.v. administration to healthy sheep. ANIMALS: 7 clinically normal female Merino sheep between 9 and 12 months old. PROCEDURE: Pharmacokinetics were determined after oral and i.v. administration of luxabendazole at a dose of 10 mg/kg of body weight. Serial blood samples were collected for 56 hours after administration. Plasma concentrations of luxabendazole were determined by high-pressure liquid chromatography. RESULTS: After i.v. administration, elimination of luxabendazole was slow, with a mean half-life of 8.72 hours. Mean steady-state volume of distribution and mean distribution volume during the elimination phase were 3.18 and 3.10 L/kg, respectively. Mean clearance was 0.24 L/kg.h, and mean area under the concentration-time curve was 41.89 mg.h/L. After oral administration, luxabendazole was slowly absorbed from the gastrointestinal tract. Mean absorption half-life was 2.26 hours. Peak plasma concentration was 0.50 microgram/ml and was detected 14 to 16 hours after drug administration. Mean area under the concentration-time curve was 12.03 mg.h/L. Mean bioavailability was 29%. CONCLUSIONS: Results suggest that luxabendazole is moderately absorbed from the gastrointestinal tract in sheep, is widely distributed into extravascular compartments, and is cleared slowly. CLINICAL RELEVANCE: Determination of pharmacokinetic parameters is the first step in determining a safe and efficacious dosage regimen for luxabendazole in sheep. PMID- 9361892 TI - Effect of alfentanil on the minimum alveolar concentration of isoflurane in cats. AB - OBJECTIVE: To evaluate effect of incremental doses of alfentanil on isoflurane minimum alveolar concentration (MAC) in cats to determine whether alfentanil reduces isoflurane MAC and, if so, maximal isoflurane MAC reduction. ANIMALS: 6 healthy spayed female cats. PROCEDURE: Cats were anesthetized with isoflurane and instrumented to allow collection of arterial blood for measurement of gas tensions, pH, and plasma alfentanil concentration and to measure arterial blood pressure. Isoflurane MAC was determined in triplicate, and alfentanil was administered i.v., using a computer-driven syringe pump to achieve estimated plasma alfentanil concentrations of 50, 100, 250, 500, 750, and 1,000 ng/ml; isoflurane MAC was determined at each alfentanil concentration. Cats were allowed to recover, and the process was graded as poor, good, or excellent. RESULTS: Alfentanil had a significant dose effect on isoflurane MAC reduction. Significant regression was found for normalized isoflurane MAC versus estimated plasma alfentanil concentration. A quadratic term was necessary to fit the model and, using this curve, MAC reduction (35.0 +/- 6.6%) was estimated to be maximal at a plasma alfentanil concentration of 500 ng/ml. Significant differences were evident in rectal temperature, bicarbonate concentration, base deficit, arterial carbon dioxide and oxygen tensions, and arterial pH between isoflurane alone and some plasma alfentanil concentration and the corresponding reduction in isoflurane concentration. CONCLUSIONS: Infusion of alfentanil resulted in maximal MAC reduction midway between that reported for horses and dogs. At such plasma alfentanil concentration, adverse effects were minimal, but included increase in rectal temperature, metabolic acidosis, and decrease in PaO2. Provided cats were not handled during the recovery period, recovery was smooth and quiet. CLINICAL RELEVANCE: Infusion of alfentanil decreases the need for potent inhalant anesthetics in cats and could potentially be a clinically useful anesthetic regimen in sick cats. PMID- 9361893 TI - Cardiovascular effects of buprenorphine in anesthetized dogs. AB - OBJECTIVE: To determine the cardiovascular effects of buprenorphine in isoflurane and halothane-anesthetized dogs. ANIMALS: 6 healthy adult hound-type dogs given buprenorphine (16 micrograms/kg of body weight, i.v.) or isovolumetric 5% dextrose solution during anesthesia with isoflurane or halothane. PROCEDURE: Each dog was anesthetized 4 times, with a minimum of 10 days between episodes. Anesthesia was induced with isoflurane or halothane in O2 by mask, and was maintained with 1.9% isoflurane or 1.3% halothane (end-tidal concentration). The PaCO2 was maintained between 35 and 45 mm of Hg by use of mechanical ventilation, and the following variables were determined: systolic, diastolic, and mean arterial blood pressures; cardiac output; cardiac index; stroke volume; heart rate; systemic vascular resistance; mean pulmonary arterial pressure; and pulmonary vascular resistance. In addition, arterial blood samples for gas and acid-base analyses were collected at 30-minute intervals for 2.5 hours. After baseline values were recorded, dogs were randomly assigned to receive either buprenorphine (16 micrograms/kg, i.v.) or isovolumetric 5% dextrose solution. All variables were then recorded at 15-minute intervals for 2.5 hours. RESULTS: During isoflurane anesthesia, buprenorphine administration caused significant (P < or = 0.05) reductions in diastolic arterial pressure, mean arterial pressure, systolic arterial pressure, cardiac index, and heart rate, whereas systemic vascular resistance increased significantly. During halothane anesthesia, buprenorphine administration caused significant decreases in heart rate, cardiac index, mean, systolic and diastolic arterial blood pressures, and stroke volume, whereas pulmonary arterial blood pressure and systemic vascular resistance increased significantly. CONCLUSION: Although the changes seen were significant, they were not sufficiently large to be of clinical importance in healthy dogs. PMID- 9361894 TI - Noninvasive monitoring of fetal heart rate during the last ten days of gestation in sows. AB - OBJECTIVE: To develop and evaluate a noninvasive technique for monitoring and analyzing porcine fetal heart rate (FHR) during late gestation. ANIMALS: 8 fetuses of 8 pluriparous sows in late gestation. PROCEDURE: With the sow positioned in lateral recumbency, the most caudal fetus was identified, using real time ultrasonography, and its heart rate was recorded for 60 minutes by use of Doppler cardiography. The same fetus was identified and monitored repeatedly during the last 10 days of gestation, excluding the 24 hours before delivery. Visual inspection and computerized analysis of the recordings were performed. RESULTS: 66 one-hour recordings were obtained from 8 fetuses, 1 in each of 8 sows. Mean signal loss was 37.5%. Episodes of low FHR and low FHR variation (FHR pattern A) alternated with episodes of high FHR and high FHR variation (FHR pattern B). This cyclic alternation between 2 distinct. FHR patterns was observed in 46 of 66 (69.7%) recordings, and suggests the presence of different behavioral states in fetal pigs. Basal FHR decreased toward parturition in 7 fetuses, but increased in 1 fetus with abdominal ascites. Basal FHR and long-term FHR variation were negatively correlated (r[S] = -0.73; P < 0.001). CONCLUSION: Noninvasive monitoring of FHR is possible and feasible during late gestation in pigs. This method permits longitudinal studies under pathophysiologic conditions and the evaluation of the effects of endogenous and exogenous influences on porcine FHR. PMID- 9361895 TI - Effect of pentoxifylline, flunixin meglumine, and their combination on a model of endotoxemia in horses. AB - OBJECTIVE: To compare effects of a single dose of pentoxifylline (PTX), flunixin meglumine (FM), and their combination (FM/PTX) in a model of equine endotoxemia. ANIMALS: 24 healthy horses, aged 2 to 15 years. PROCEDURE: 4 groups (n = 6/group) received 30 ng of Escherichia coli O55:B5 endotoxin/kg of body weight, i.v., over 30 minutes, and 1 of the following preparations 15 minutes before and 8 hours after endotoxin infusion: FM, 1.1 mg/kg; PTX, 8 mg/kg; FM/PTX, 1.1 mg of FM and 8 mg of PTX/kg; and saline solution bolus (ENDO). Clinical and hematologic variables were measured over 24 hours. RESULTS: Compared with ENDO, FM given before endotoxin significantly reduced TxB2, and 6-keto-PGF1 concentrations, pulse, rectal temperature, and attitude score. Pentoxifylline given before endotoxin resulted in significantly higher 6-keto-PGF1 concentration at 1.5 hours and significantly lower PAI-1 activity at 12 hours. Tumor necrosis factor and IL 6 activities in horses given PTX alone were not significantly different from values in those given the saline bolus. FM/PTX induced effects similar to those of FM alone on endotoxin-induced changes in temperature and TxB2 concentration, and 6-keto-PGF1 concentration was significantly lower than that in horses of the ENDO group at 1 hour. In horses of the FM group, 6-keto-PGF1 concentration was significantly lower than that in horses of the ENDO group, from 0.5 hour to 2 hours. Horses of the FM and FM/PTX groups had significantly higher IL-6 activity at 1.5 and 2 hours than did horses of the PTX and ENDO groups; those of the FM and FM/PTX groups had significantly lower WBC count than did those of the PTX and ENDO groups. CONCLUSIONS: FM/PTX may help offset deleterious hemodynamic effects of endotoxin more effectively than does either FM or PTX alone. PMID- 9361896 TI - Effects of pentoxifylline infusion on response of horses to in vivo challenge exposure with endotoxin. AB - OBJECTIVE: To evaluate the effect of pentoxifylline on response of horses to in vivo challenge exposure with endotoxin. ANIMALS: 24 healthy horses in 3 treatment groups: pentoxifylline, endotoxin, or endotoxin and pentoxifylline. PROCEDURE: Horses of the pentoxifylline group were given a bolus of pentoxifylline (7.5 mg/kg of body weight, i.v.), followed by an infusion (3 mg/kg/h) over 3 hours, and those of the endotoxin group were given 20 ng of endotoxin/kg i.v. over 30 minutes. Those of the combination group were given both of the aforementioned compounds; pentoxifylline was administered immediately after endotoxin. Clinical (rectal temperature, heart and respiratory rates, blood pressure) and hematologic (WBC count; whole blood recalcification time; plasma fibrinogen, thromboxane B2, and 6-keto-prostaglandin F1 alpha concentrations; plasma plasminogen activator inhibitor activity; and serum tumor necrosis factor and interleukin 6 activities) variables were evaluated over 24 hours. RESULTS: Compared with baseline values, there were no significant changes in any variable over time in the horses receiving only pentoxifylline, with the exception of a significant increase in WBC count. Rectal temperature, heart rate, mean blood pressure, WBC count, whole blood recalcification time, fibrinogen concentration, plasminogen activator inhibitor activity, tumor necrosis factor and interleukin 6 activities, and plasma thromboxane B2 concentration changed significantly over time in horses of the endotoxin and endotoxin-pentoxifylline combination groups. Respiratory rate and plasma 6-keto-prostaglandin F1 alpha concentration changed significantly over time only in horses of the endotoxin group. Compared with values for the endotoxin group, rectal temperature and respiratory rate were significantly lower, and whole blood recalcification time was longer for the endotoxin/pentoxifylline group. CONCLUSION: Beneficial effects of pentoxifylline are limited when it is administered i.v. to horses after in vivo challenge exposure with endotoxin. PMID- 9361898 TI - Use of a breath test to determine the fate of swallowed fluids in cattle. AB - OBJECTIVE: To investigate a [13C]octanoic acid breath test as a means of detecting reticular groove contraction in cattle. ANIMALS: 19 adult dairy cows with fistulated rumen, 10 yearling bulls, and 6 yearling steers. PROCEDURE: Cows were given 200 mg of [13C]octanoic acid in the caudal portion of the rumen, reticulum, or omasum/abomasum through the reticulo-omasal orifice, or were given the same dose of label with a drench of water or sodium bicarbonate. Collected breath was analyzed for 13C in CO2 for up to 3 hours. Breath of yearlings was analyzed for 13C in CO2 over 20 minutes after drenching with 200 mg of [13C]octanoic acid with water or sodium chloride and after sucking 200 mg of [13C]octanoic acid with molasses and water. RESULTS: In cows, enrichment of 13C in breath CO2 peaked at 20 to 30 minutes after placement of [13C]octanoic acid through the orifice, compared with a lower peak at 60 and 90 minutes after placement in the reticulum and rumen, respectively. The maximal increase in enrichment after placement of [13C]octanoic acid in the reticulum did not overlap with the minimal increase when placed through the reticulo-omasal orifice. Enrichment values in cows after drenching were consistent with values obtained after direct placement of [13C]octanoic acid. In yearlings, the inclusion of sodium chloride in the drench greatly increased enrichment, compared with water, but enrichment was greatest after sucking of the molasses, water, and [13C]octanoic acid combination. CONCLUSIONS AND CLINICAL RELEVANCE: This breath test provides a simple, repeatable, nonradioactive, and noninvasive means of detecting the fate of swallowed fluids in cattle, thus revealing the route taken of orally administered therapeutic agents or nutrients. PMID- 9361897 TI - Mitogenic effects of epidermal growth factor and platelet-derived growth factor on canine and equine mesangial cells in vitro. AB - OBJECTIVE: To evaluate the effects of epidermal growth factor (EGF) and platelet derived growth factor (PDGF) on canine and equine mesangial cell (MC) proliferation in vitro. SAMPLE POPULATION: Third- through eighth-passage canine and equine MC were obtained from explant outgrowth after differential sieving of glomeruli isolated from the kidneys of clinically normal dogs and horses. PROCEDURE: Mitogenic effects of serum, insulin, EGF, and PDGF were evaluated in MC by induction of DNA synthesis, measured as stimulation of [3H]thymidine incorporation and increase in cell numbers. RESULTS: Epidermal growth factor was a potent mitogen in canine and equine MC, stimulating dose-dependent increases in [3H]thymidine incorporation and moderate increase in cell numbers. Although PDGF alone did not significantly stimulate [3H]thymidine incorporation in canine MC, PDGF was synergistic with EGF in stimulation of [3H]thymidine incorporation in canine and equine MC, and PDGF significantly stimulated [3H]thymidine incorporation in equine MC. CONCLUSIONS: Both EGF and PDGF are important mediators of canine and equine MC proliferation. CLINICAL RELEVANCE: Our results are consistent with the hypothesis that growth factors have a role in the progression of glomerular disease in dogs and horses. These findings could prove to be of diagnostic, prognostic, and therapeutic value in the management of spontaneous renal disease in these species. PMID- 9361899 TI - Clinical evaluation of cimetidine, sucralfate, and misoprostol for prevention of gastrointestinal tract bleeding in dogs undergoing spinal surgery. AB - OBJECTIVE: To determine the incidence of gastrointestinal (GI) tract bleeding in dogs undergoing spinal surgery with adjunct corticosteroid treatment, and to determine the protective efficacy of cimetidine, sucralfate, and misoprostol against such bleeding in these dogs. ANIMALS: 40 dogs that underwent spinal surgery. PROCEDURES: Myelography and surgery were performed on the first or second day of hospitalization. Methylprednisolone sodium succinate was given at a dosage of 30 mg/kg of body weight prior to myelography, followed by a second full or half dose 2 to 4 hours later at clinician discretion. Spinal surgery was performed in conventional manner, postoperative administration of analgesics was done, and dogs were fed a diet lacking red meat. Dogs were assigned at random to 1 of the 3 treatment groups or to the control group. Dogs of the treatment groups received cimetidine, sucralfate, or misoprostol. Physical examination and determination of PCV and serum total protein values were performed daily. A fecal sample was examined daily for gross and occult blood. RESULTS: 36 of 40 dogs had GI tract bleeding during a hospitalization period of 3 to 6 days. There was no significant difference in development of bleeding between the control group and any of the treatment groups. CONCLUSIONS: Gastrointestinal tract bleeding occurred in 90% of dogs undergoing spinal surgery combined with administration of methylprednisilone sodium succinate, a higher rate than that found in previous studies. This bleeding was not life-threatening. Prophylactic benefit from any of the GI protectants tested was not found. PMID- 9361900 TI - Effects of high-dose gentamicin sulfate on neuromuscular blockade in halothane anesthetized horses. AB - OBJECTIVE: To evaluate effects of a single high dose of gentamicin on neuromuscular function in horses anesthetized with halothane. ANIMALS: 6 healthy adult horses. PROCEDURE: Halothane-anesthetized horses were positioned in left lateral recumbency, and the right hind limb was immobilized in a reusable fiberglass cast fixed to a steel frame. The hoof was attached to a force transducer, and resting tension of 0.93 +/- 0.16 kg was maintained. A supramaximal train-of-four stimulus of 2 Hz for a duration of 0.25 millisecond was applied to the superficial peroneal nerve every 20 seconds by a square-wave stimulator. The force of the evoked digital extensor tension was recorded to determine first muscle twitch tension, compared with the baseline value (T1%) and the ratio of the force of the fourth twitch to the first twitch (T4/T1). Data were recorded at 5, 10, 15, 30, and 60 minutes after i.v. administration of vehicle or gentamicin (6 mg/kg of body weight). RESULTS: There was a significant (P = 0.04) treatment-time interaction for the effect of gentamicin on T1%; T1% associated with vehicle decreased from 100% to 92% during the 60- minute study period, but no decrease was associated with gentamicin. For T4/T1, there was no significant effect of treatment or time or treatment-time interaction between gentamicin and vehicle. CONCLUSIONS: Gentamicin did not cause a decrease in initial muscular strength, nor did it impair the muscles' ability to sustain strength. CLINICAL RELEVANCE: A single high dose of gentamicin does not cause significant neuromuscular blockade when administered alone to healthy horses anesthetized with halothane. PMID- 9361902 TI - In vitro flow characteristics of the Ahmed and self-constructed anterior chamber shunts. AB - OBJECTIVE: To compare in vitro opening pressures (OP) and closing pressures (CP) of the Ahmed VS-1 and VS-2 glaucoma valves with those of several self-constructed valve 'prototypes,' and to assess their ability to maintain perfusion pressures between 6 and 21 mm of Hg. SAMPLE POPULATION: Ahmed VS-1 (n = 6), 2 groups of Ahmed VS-2 (group 1: n = 12; group 2: n = 14), and self-constructed valves with linear incisions in the long axis of the tube wall (n = 6) or X-shaped incisions in the tube walls (n = 2). PROCEDURE: Valves were perfused with deionized water, lactated Ringer's solution (LRS), Dulbecco's modified Eagle's medium (DMEM), DMEM plus 50% equine serum (ES), and 100% ES. Flow rates of 2.85, 4.2, 6.0, 9.0, and 12.0 microliter/min were used for each perfusate. Valves were tested 3 times for reproducibility, and OP/CP were compared for each system. RESULTS: OP/CP of the VS-1, VS-2 (group 1), VS-2 (group 2), and linear 1.0-cm incisional valves with thick tubing consistently increased with increasing perfusion rate. Linear 0.5-cm (thick tubing) and 1.0-cm (thin tubing) incisional valves had increasing OP/CP with increasing perfusion rate in all but a few instances. Mean OP/CP decreased with increasing perfusate osmolarity for all perfusates except LRS, using the VS 1 and V-2 (group 2) valves. Mean OP/CP were consistently lower for VS-1 than VS-2 (group 1) valves at any given flow rate and for any given perfusate. Mean OP/CP were consistently lower for VS-2 (group 1) than VS-2 (group 2) valves at any given flow rate and for any given perfusate. The linear 0.5-cm incisional valves with thick and thin tubing induced the highest mean OP/CP, maximizing at > 30 mm of Hg. CONCLUSIONS: Only the VS-2 (group 2) valves consistently had mean OP/CP between 6 and 21 mm of Hg for all perfusates and at all flow rates. CLINICAL RELEVANCE: Anterior chamber shunts, although imperfect, appear to offer a physiologically sound alternative for glaucoma management. PMID- 9361901 TI - Pathogenesis of experimentally induced rabies in domestic ferrets. AB - OBJECTIVE: To determine susceptibility, incubation and morbidity periods, clinical signs, serologic response, and excretion of virus in domestic ferrets inoculated with rabies virus. ANIMALS: 55 domestic ferrets. PROCEDURE: 5 groups of 10 ferrets were inoculated with rabies virus, IM, at doses of 10(5.5) to 10(1.5) median mouse intracerebral lethal dose. Ferrets were observed and behavior was recorded. Rectal temperature, body weight, and samples from the oral cavity and samples of saliva and blood were obtained. Virus isolation was attempted, using intracranial mouse inoculation and cell culture. Virus neutralizing antibodies were determined by rapid fluorescent focus inhibition test. Ferrets were euthanatized immediately if clinical signs were severe. Rabies was confirmed by direct immunofluorescent antibody test. RESULTS: Mean incubation period was 33 days (range, 16 to 96 days). Clinical signs included ascending paralysis, ataxia, cachexia, bladder atony, fever, hyperactivity, tremors, and paresthesia. Mean morbidity period was 4 to 5 days (range, 2 to 10 days). Virus antigen was detected in brain tissue from all clinically rabid ferrets. Ferrets given the highest viral dose were euthanatized and had VNA; ferrets receiving the next dilution also were euthanatized, but only 4 had seroconverted. Of 17 ferrets that survived, 5 seroconverted. Survivors remained clinically normal except for 1 that recovered with severe paralytic sequelae. Rabies virus was isolated from the salivary gland of 1 ferret that was euthanatized. CONCLUSIONS AND CLINICAL RELEVANCE: Rabies should be considered as a differential diagnosis in any ferret that has acute onset of paralysis or behavioral changes and a condition that rapidly deteriorates despite intense medical intervention. PMID- 9361903 TI - Room temperature storage and cryopreservation of canine platelet concentrates. AB - OBJECTIVE: To determine whether in vitro viability and function, and microbiological sterility, of canine platelet concentrates (PC) could be retained during storage at 20 to 24 C (room temperature [RT]) for up to 7 days and cryopreservation for 6 months. ANIMALS: 14 mature dogs. PROCEDURE: PC prepared by centrifugation of fresh blood were stored for 7 days at RT with continuous agitation. An aliquot of each was cryopreserved with 6% dimethyl sulfoxide at -74 C for 6 months. Fresh PC (day 0) were tested by microbial culture and measurement of platelet count, mean platelet volume, pH, glucose and lactate concentrations, lactate dehydrogenase activity, response to hypotonic stress, and aggregation. Tests were also performed on PC stored at RT on days 3, 5, and 7, and on the cryopreserved aliquots after thawing. RESULTS: After 7 days at RT, microbial growth was not evident, and decrease in platelet number was not significant. On the basis of pH and glucose and lactate concentrations, metabolic activity was maintained throughout RT storage. On the basis of mean platelet volume and lactate dehydrogenase activity, platelet swelling and membrane damage had occurred. Aggregatory responses decreased during RT storage, and platelets recovered poorly from hypotonic stress. After cryopreservation for 6 months, microbial growth was not evident, but platelet numbers were significantly decreased. Mean platelet volume and lactate dehydrogenase activity were significantly greater, compared with values for day-0 PC. Crypreserved platelets aggregated poorly and did not respond to hypotonic stress. CONCLUSIONS: Platelet viability and microbiological sterility are retained in canine PC stored for 7 days at RT, but platelet function pregressively decreases and day-7 platelets are substantially damaged. Crypreservation of PC results in considerable damage, compared with that of PC stored at RT. CLINICAL RELEVANCE: Similar to human PC, canine PC stored at RT for up to 5 days can be recommended for treatment. PMID- 9361904 TI - Sequence-specific inhibition of the tumor necrosis factor-alpha receptor I gene by oligodeoxynucleotides containing N7 modified 2'-deoxyguanosine. AB - Tumor necrosis factor-alpha (TNF-alpha) is a highly pleiotropic cytokine produced mainly by activated macrophages. This cytokine has been found to mediate the growth of certain tumors, the replication of HIV-1, septic shock, cachexia, graft versus-host disease, and autoimmune diseases. The binding of TNF-alpha to the p55 tumor necrosis factor receptor type I (TNFRI) is considered one of the initial steps responsible for the multiple physiologic effects mediated by TNF-alpha. The role of TNF-alpha as an inflammatory mediator through TNFRI makes both of these genes attractive targets for intervention in both acute and chronic inflammatory diseases. We have designed antisense oligodeoxynucleotides (ODNs) containing chemically modified purine and pyrimidine bases that specifically inhibit TNFRI expression and functions. These ODNs were designed to hybridize to the 3' polyadenylation signal region of the TNFRI gene. In cell-based assays, gene specific antisense inhibition occurred in a dose-dependent fashion at submicromolar concentrations in the presence of cellular uptake enhancing agents. Within ODN sets with a common pattern of stabilizing backbone substitution, the inhibition of the gene expression is found to be correlated with the affinity of the ODNs for their cognate mRNA target sites, providing direct evidence for an antisense mechanism of action. In addition, events triggered by the binding of TNF-alpha to TNFRI, such as the production of IL-6 and IL-8, were significantly reduced by treatment of cells with the anti-TNFRI ODN. Therefore, antisense ODNs can be used to control biologic processes mediated by TNF-alpha and may be useful as therapeutic agents to treat conditions resulting from overproduction of TNF alpha. PMID- 9361905 TI - Characterization and modulation of immune stimulation by modified oligonucleotides. AB - Single-stranded oligodeoxynucleotides (ODNs) were tested for their ability to stimulate NK cells isolated from murine spleens to lyse target cells. Various sequences were evaluated, some of which have been shown previously to exhibit pharmacologic activity in murine model systems. It was confirmed that the CpG motif was stimulatory only in specific sequence contexts, and we found that phosphorothioate backbones were, in general, less stimulatory than phosphodiester backbones. In addition, this stimulation could be reduced by methylating the cytosine of the CpG and eliminated by modifying all of the cytosines contained in an ODN with methyl, bromo, or iodo modifications to the 5 position of the cytosine ring. These results were compared with the ability of a subset of these ODN sequences to stimulate B cell proliferation in vitro. In this comparison, phosphorothioate backbones were found to be required, and the context of the CpG motif was found to be less critical for activation. Finally, one of the most potent ODNs was shown to activate NK and B lymphocytes when administered in vivo. PMID- 9361906 TI - Evaluation of the toxicity of ISIS 2302, a phosphorothioate oligonucleotide, in a 4-week study in CD-1 mice. AB - The subchronic toxicity of ISIS 2302 and ISIS 3082, phosphorothioate oligonucleotides with antisense activity against human and murine ICAM-1 mRNA, respectively, was investigated in CD-1 mice. ISIS 2302 is currently in clinical trials as an anti-inflammatory agent. Because of the differences in mRNA sequence targets between humans and mice, ISIS 2302 has no pharmacologic activity in mice. ISIS 3082 was specifically designed to inhibit murine ICAM-1 and was included in this study to evaluate the effects of prolonged ICAM-1 inhibition. The oligonucleotides were administered by bolus i.v. injection (via tail vein) every other day for 27 days (14 doses) at dose levels of 0, 0.8, 4, 20, and 100 mg/kg per injection ISIS 2302 or 20 mg/kg per injection ISIS 3082. The basic group size consisted of 10 male and 10 female mice, which were sacrificed 2 days after the last dose and an additional 5 mice per sex in vehicle control and 100 mg/kg ISIS 2302 dose groups, which remained on study for a 28-day treatment-free period. No treatment-related deaths occurred during this study, and there were no effects of either oligonucleotide on body weight gain or food consumption. The most common changes observed in this study included a mixed mononuclear cell infiltrate seen in a number of organs or tissues, splenomegaly, and lymphoid hyperplasia at dose levels of > or = 20 mg/kg ISIS 2302. In the group that received the highest dose level of ISIS 2302 (100 mg/kg), there were alterations in serum chemistry parameters that appeared to be related to perturbations in the liver, including 3 to 4-fold increases in aspartate and alanine aminotransferase and smaller changes in bilirubin, alkaline phosphatase, cholesterol, triglycerides, and albumin levels. Treatment-related effects on hematologic parameters were limited to the 100 mg/kg ISIS 2302 dose group and included slight monocytosis and thrombocytopenia. None of the effects observed appeared to be life threatening. Complete or partial reversal of all effects was evident in the remaining high dose ISIS 2302 animals at the end of the 4-week recovery period. Comparison of the effects produced by the same dose level (20 mg/kg) of ISIS 2302 and ISIS 3082 did not reveal any differences that could be attributed to exaggerated pharmacology. In conclusion, treatment-related alterations were observed primarily at the 100 mg/kg dose level, including immune stimulation and hepatic alterations, which were partially reversed following a 4-week treatment-free period. PMID- 9361907 TI - Cationic polyhexylcyanoacrylate nanoparticles as carriers for antisense oligonucleotides. AB - After antisense oligodeoxynucleotides (ODNs) were suggested for therapeutic use in 1978, major advances were made in developing modified oligonucleotides with increased nuclease resistance and improved cellular uptake. In the present report, positively charged nanoparticles prepared from diethylaminoethyl (DEAE) dextran and polyhexylcyanoacrylate (PHCA) were evaluated as carriers for ODNs. The oligonucleotides were analyzed by anion-exchange HPLC. The nanoparticles exhibited a high loading capacity, with approximately 35 mumol ODNs adsorbed per gram of polymeric material. The adsorption efficacy was found to be dependent on the pH, on the ionic strength of the medium, and on the amount of DEAE-dextran. Highest loading for ODNs was achieved at pH 5.5, using a 10 mM phosphate buffer. Oligonucleotides adsorbed to the surface of the nanoparticles were nearly completely protected against degradation by the endonuclease DNase I and under in vitro cell culture conditions, whereas unprotected ODNs were totally digested under these conditions. Nanoparticles led to a 20-fold increase in cellular uptake of FITC-oligonucleotides. The internalized oligonucleotides were frequently localized as vesicular structures in the cytoplasmatic compartment. Because of their temperature-dependent uptake, we propose an active uptake mechanism, such as endocytosis, for the internalization of the ODN-nanoparticle formulations. PMID- 9361908 TI - Pattern and kinetics of cytokine production following administration of phosphorothioate oligonucleotides in mice. AB - Phosphorothioate oligonucleotides with certain sequences or structure motifs can stimulate the immune system. We administered to mice a 27-mer phosphorothioate oligonucleotide (sequence 5'-TCG TCG CTG TCT CCG CTT CTT CTT GCC-3'), which has previously been shown to cause splenomegaly and hypergamma-globulinemia on in vivo administration in mice, and studied the pattern and kinetics of cytokine production at both the splenic mRNA and serum protein levels. Following i.p. administration of 50 mg/kg of oligonucleotide, significant increases in the splenic mRNA levels of IL-6, IL-12p40, IL-1 beta, and IL-1Ra and serum levels of IL-6, IL-12, MIP-1 beta, and MCP-1 were observed. In contrast, no significant differences in splenic mRNA levels of IL-2, IL-4, IL-5, IL-9, IL-13, IL-15, IFN gamma, or MIF or serum levels of IL-2, IL-4, IL-5, IL-10, IFN-gamma, or GM-CSF were detected. The induction of IL-12 secretion was dependent on the sequence and dose of the oligonucleotides. One oligonucleotide (sequence 5'-GAG AAC GCT CGA CCT TCG AT-3') induced a high level of IL-12 secretion even at 5 mg/kg, whereas another oligonucleotide (sequence 5'-CTC TGC CAC CCA TCT CTC TCC TTC T-3') did not induce significant IL-12 secretion even at 50 mg/kg. IL-12 secretion induced by various doses of oligonucleotide has the same kinetics but differs in magnitude. These studies show a distinct pattern and kinetics of cytokine production following oligonucleotide administration and further demonstrate that cytokine induction is not a general property of phosphorothioate oligonucleotides but is dependent on the sequence and dose of the oligonucleotides. PMID- 9361909 TI - Inhibition of coagulation by a phosphorothioate oligonucleotide. AB - In the development of antisense therapeutics, there have been a number of hybridization-independent effects characterized for phosphorothioate oligodeoxynucleotides. One such effect is the transient prolongation of clotting times following intravenous infusion of high doses. In this study, inhibition of clotting times was characterized by determining the time course of both APTT and plasma oligonucleotide following intravenous infusion of ISIS 2302 in cynomolgus monkeys. Prolongation of APTT was also achieved by addition of ISIS 2302 to citrated blood from untreated monkeys, allowing the investigation of the mechanism of inhibition in vitro. Results from this study clearly indicate that the intrinsic pathway (APTT) was more sensitive to inhibition than the extrinsic pathway (PT). The prolongation of APTT was also shown to be transient and closely correlated with plasma oligonucleotide concentrations. The extent of APTT prolongation can be controlled by minimizing peak plasma oligonucleotide concentrations through lowering the dose or prolonging infusion duration. Direct addition of ISIS 2302 to blood produced quantitatively similar inhibition of clotting times. This effect was similar for a number of different phosphorothioate oligodeoxynucleotides, but oligonucleotides containing phosphodiester linkages and 2'-propoxy linkages were much less inhibitory. Additional in vitro studies indicated that the mechanism of inhibition was independent of that of heparin and possibly involved selective inhibition of the intrinsic pathway as well as the common clotting pathway. Investigation of selective clotting factors indicated that there was no direct inhibition of the enzymatic activity of factor Xa, XIa, or thrombin using chromogenic substrates. However, ISIS 2302 did produce a concentration-dependent increase in clotting time when fibrinogen was used as the substrate for thrombin. PMID- 9361910 TI - Efficient long-term coexpression of a hammerhead ribozyme targeted to the U5 region of HIV-1 LTR by linkage to the multidrug-resistance gene. AB - Ribozymes as anti-HIV-1 agents hold promise for the treatment of AIDS. They can be delivered into cells either exogenously or through an expression system. For effective protection against HIV-1, sufficient and sustained amounts of the antiviral ribozymes must be delivered into target cells. The coexpression of a dominant selectable marker with ribozymes would serve to enrich for cells containing the molecular antiviral and facilitate prolonged expression of these ribozymes. The multidrug resistance gene (MDR1) is a potential clinically relevant selectable marker and offers many advantages over other known dominant selectable markers, including the use of diverse pharmacologically characterized drug or drug combinations for selection. Harvey sarcoma-based retroviral vectors encoding the MDR1 multidrug transporter with a hammerhead ribozyme targeted to highly conserved sequences within the HIV-1 U5 LTR segment have been constructed in a bicistronic format. The internal ribosome entry site (IRES) from encephalomyocarditis virus was used to initiate translation of the MDR1 mRNA. The ribozyme remained functional despite being tethered to MDR1. Long-term, high level expression of both the ribozyme and MDR1, as evident by RT-PCR and FACS analysis, was observed in a human T cell line containing the construct selected with vincristine, a cytotoxic substrate for the multidrug transporter. PMID- 9361911 TI - Triplex-forming oligonucleotides can modulate aquaporin-5 gene expression in epithelial cells. AB - Triplex-forming oligonucleotides (TFOs) may provide a useful approach to decrease gene transcription in vivo. We have identified two sequences in the rat aquaporin 5 (rAQP5) cDNA that are capable of forming a DNA triple helix. We designed four TFOs based on these sequences (a purine and a pyrimidine TFO per sequence). All four TFOs were able to bind to the rAQP5 cDNA at varying efficiencies in vitro as measured by using gel mobility shift assays. The TFOs were delivered to intact MDCK epithelial cells via adenovirus-polylysine complexes. Experiments with fluorescein-isothiocyanate-labeled oligonucleotides delivered in this way showed primarily a nuclear localization. Three of the four TFOs internalized by adenovirus-polylysine complexes were capable of decreasing rAQP5 expression in intact MDCK cells infected with a recombinant adenovirus encoding rAQP5. These data show that adenovirus-polylysine-TFO complexes can result in TFO delivery to the nucleus in intact epithelial cells and that TFOs may provide a useful way to selectively modulate rAQP5 gene expression. PMID- 9361912 TI - Deep vein thrombosis after uncemented total hip replacement. AB - One-hundred-fourteen consecutive cases of venography after primary uncemented total hip replacement were performed in a randomized trial to identify the natural incidence of deep vein thrombosis, the effectiveness of prophylactic regimens such as 1.2 grams of aspirin daily and low-molecular-weight dextran for 3 days, and other relative factors for the development of venous thrombosis. In addition, intraoperative venography was conducted in 10 patients to study the speed of the flow of contrast media in the femoral vein and the development of deep vein thrombosis and the extent of the twisting of the femoral vein during hip joint manipulation. The incidence of venous thrombosis in the control, aspirin, and dextran prophylaxis groups were 20%, 11.5%, and 5.2% respectively. The incidence in the aspirin group was reduced, but this was statistically insignificant. The dextran group showed a marked decrease in incidence, and the difference with the control group was statistically significant. With regard to the development site of venous thrombosis, it was prevalent in iliofemoral, lower femoral, and major calf vein in the control group, while the popliteal and major calf vein were the major site of thrombosis development in the aspirin and dextran groups. The risk factors affecting the incidence of the venous thrombosis are confirmed to be obesity and long-term administration of steroids. Hematologic analysis was meaningless in investigating the development of venous thrombosis. The reliable clinical sign and symptom suggestive of the development of venous thrombosis was the severe swelling on the entire portion of affected lower extremity. In the intraoperative venogram, no correlation was found between the venous blood flow speed and the development of venous thrombi. A remarkable change in the blood flow of the femoral vein was noticed when the hip joint was flexed an average of 40.4 degrees, adducted at 11.5 degrees, and internally rotated at 81.5 degrees. Especially, when the joint was internally rotated, severe kinking of the vein could be observed. Thus it seems desirable to reduce the duration of internal rotation of the hip joint as much as possible to prevent venous thrombosis. PMID- 9361913 TI - Antibiotic-impregnated cement beads in the treatment of chronic osteomyelitis. AB - Fifty-four patients with chronic osteomyelitis of the long bones were treated at Gyeong-Sang National University Hospital between 1985 and 1993 using the cement bead technique. We studied the results of thirty-one patients who were followed up for 3 years or more. The average duration of follow-up was 4 years and 2 months (range: 3 to 7 years). All of the patients were treated by a two-stage operation; primary saucerization with implantation of antibiotic-impregnated polymethylmethacrylate beads and secondary bone grafts. The most recent follow-up examinations and analyses revealed that 17 patients (55%) were completely free of infection. Ten patients (32%) required repeated procedures of curettage and/or bone grafting. Amputations were performed on 4 patients. PMID- 9361914 TI - Varus and internal rotational deformity of the ankle secondary to distal tibial physeal injury. AB - Nine children who sustained Lauge-Hansen's supination-inversion injury of distal tibial physeal injury with intact distal fibular physis, were followed until their maturity. The average varus deformity was 39 degrees (maximum, 80 degrees) with 23 degrees of internal rotational deformity. The longitudinal growth of the fibula was retarded compared with opposite normal leg. There was early closure of the medial distal tibial physis, gradual upward migration of medial malleolus, and eventually medial subluxation of the ankle; these resulted in gradual varus and internal rotational deformities of the injured ankle. It is thought that the resultant disabling deformity of ankle should be prevented by any means, though presently there are no available effective methods of treatment. It is suggested that the repeated corrective osteotomy should be carried out before epiphyseal deformity of the distal tibia and subluxation of the ankle joint develop. PMID- 9361916 TI - Arthroscopic second look findings of an anterior cruciate ligament bone-patellar tendon-bone autograft. AB - Nineteen patients who had undergone reconstruction of a deficient anterior cruciate ligament (ACL) by a bone-patellar tendon-bone (BPTB) autograft 12 months or more before (mean: 15.8 months) were evaluated by second-look arthroscopy. Prior to the arthroscopic evaluation the patients underwent a clinical evaluation of the results of ACL reconstruction: Muller's knee rating score and the radiographic results from lateral radiographs of the full extended knees were used. The location of the center of the tibial tunnel from the anterior end of the line of the tibial plateau was 35.2% (range: 22% to 47%) on average. The average intercondylar roof angle was 36.6 degrees (range: 28 degrees to 45 degrees). The mean percentage of roof impingement was -13.5% (range: -55% to +23%; the negative value implies no impingement, while the positive value suggests the presence of impingement). During the second-look arthroscopy the ACL graft had one or more of the following features: nearly normal appearance, incomplete synovial coverage, partially torn fibers at the femoral tunnel site, parallel fragmentation with cyclops lesion, and impingement without the damage of the ACL graft. Biopsy specimens were obtained from the nearly normal ACL graft during the second-look arthroscopy and light microscopic findings showed dense collagen fibers and spindle-shaped fibroblasts with a relatively regular arrangement (H&E, X 200). The electron microscopic findings showed that the fibroblasts had prominent indented nuclei and an abundant rough endoplasmic reticulum (X 10,200) and that the longitudinal sections of extracellular collagen fibrils demonstrated a type I collagen banding pattern (X 50,000). PMID- 9361915 TI - Valgus ankle secondary to acquired fibular pseudoarthrosis in children. Long-term results of the Langenskiold operation. AB - Nine cases of acquired absence of the fibular shaft were studied to determine the growth contribution of the distal fibula; in 6 cases the absence was caused by osteomyelitis and in 3 cases by trauma. The average valgus and external rotational deformities were 15.2 degrees and 10 degrees, respectively. In 3 of 7 cases surgically treated with Langenskiold operation or supramalleolar corrective osteotomy, the valgus deformity recurred during the postoperative growth period. The speculated causes of gradual valgus deformity are the loss of physiologic thrust from the proximal to distal fibula, the tethering effect of contracted soft tissue on distal fibula and early physeal closure of the lateral part of the distal tibia due to continuous, uneven axial overloading. The Langenskiold operation was found effective for the stability of ankle joint in the initial period, but could not prevent the postoperative revascularization of the ankle. However, it is strongly recommended that any types of prophylactic surgery should be carried out before the development of an epiphyseal deformity of distal tibia, and to prevent secondary osteoarthritis of the ankle joint. PMID- 9361917 TI - The role of transitional vertebrae in spondylolysis and spondylolytic spondylolisthesis. AB - Transitional lumbar vertebrae include lumbarization and sacralization of the lumbosacral region. This study was performed to evaluate the relationship of transitional vertebra to spondylolytic spondylolisthesis such as the incidence and degree of slippage and to ascertain the clinical relevance for treatment. The study included 182 cases with 33 cases (18.1%) of transitional vertebra, 12 cases of lumbarization, and 21 cases of sacralization. The remaining 149 cases constituted the control group. The degree of the anterior slippage of the vertebral body was measured by Meyerding's grading and the percentage of the anterior slippage was measured by Taillard's method. In the patients with lumbarization and the isthmic defects in the fourth lumbar spine, the average slip of L4 was 14.5%. While patients with sacralization and the isthmic defects in L4, the average slip of L4 was 19.3%. The average slip of L4 was 11.4% in the control group. In patients with lumbarization and the isthmic defects in the fifth lumbar vertebra, the average slip of L5 was 12.5%. While in patients with sacralization and the isthmic defects in L5, the average slip of the L5 vertebra was 9.5%. The average slip of L5 was 16.2% in the control group. The patients with sacralization and the isthmic defects in L4 showed more anterior slippage than the patients with the isthmic defect in L4 without transitional vertebrae. The patients with sacralization and the isthmic defects in L5 showed less anterior slippage than the patients with isthmic defects in L5 without transitional vertebrae. From this it can be concluded that more aggressive treatment is recommended in the patients with sacralization and isthmic defects in L4, whereas more conservative treatment is recommended in the patients with sacralization and the isthmic defects in L5. PMID- 9361918 TI - A newly designed miniplate staple for high tibial osteotomy. AB - A biomechanical study was made to compare the mechanical performance of the newly designed Miniplate staple to the conventional Coventry staple in high tibial osteotomy (HTO). Using twenty fresh porcine tibiae, the fixational strength of the two different types of staples in HTO was compared. To minimize the error due to the specimen-to-specimen individuality, the bone mineral density of the tibiae was measured with bone densitometry and those with 0.8 to 1.2 gm/cm2 at the proximal tibia were used in the biomechanical test. Testing was performed on a material testing system with aid of a commercial data processor. Using two different loading modes, "pull-out" and "push-out," the maximum resistant force required to release the staple from the substrate bone was recorded. In the pull out test, ten nonosteotomized specimens were used and the staple was pulled out by subjecting an axial tension on the head of the staple inserted. In the push out test ten tibiae osteotomized in the usual method of HTO were used and the staple was not directly loaded. In this testing, as a mimic condition of the natural knee, the proximal part of the specimen tibia was pushed horizontally in order for the staple to be pulled out while the distal tibia was fixed. The pull out strength of Coventry staple and Miniplate staple were found to be 27.88 +/- 5.12 kgf and 182.47 +/- 32.75 kgf, respectively. The push-out strength of Coventry staple and Miniplate staple were 18.40 +/- 4.47 kgf and 119.95 +/- 19.06 kgf, respectively. The result revealed that the Miniplate staple has both a pull out and push-out strength that is more than six times higher than Coventry staple. Based on the data, it is believed that the Miniplate staple provides better postoperative fixation in HTO. The postoperative application of long leg casting may not be needed after HTO surgery. PMID- 9361919 TI - A new suggestion for the treatment of minimally displaced fractures of the greater tuberosity of the proximal humerus. AB - Fourteen shoulders in 14 patients with minimally displaced fractures of the greater tuberosity of the proximal humerus were evaluated, at an average of 3 years, 7 months (range: 1 year to 6 years, 1 month) after the operation. For comparison this portion of the proximal humerus was measured using 100 Korean adult cadaveric humeri. The results of these preliminary studies suggest that the patients presenting with a one-part fracture of the greater tuberosity of the proximal humerus should be evaluated individually. In most patients in whom the displacement of the fragment is less than 5 mm, good results can be obtained with non-operative treatment. If the displacement of the fragment is more than 5 mm in young active patients, and more than 3 mm in individuals (especially athletes and heavy laborers) involved in overhead activity, the fragment should be mobilized, repaired, and fixed into its original bed or slightly inferolaterally. PMID- 9361920 TI - Snapping knee caused by the gracilis and semitendinosus tendon. A case report. AB - There are many reports about the snapping syndrome in the hip, shoulder, and ankle, but the snapping knee has rarely been reported. In general, the symptom of this disorder is relatively tolerable and seldom requires operative treatment. We experienced one case of the snapping knee, for which the pain, easy fatigability, and feeling of instability on both knee joints were the main complaints. During an exploratory operation, we confirmed the gracilis and semitendinosus tendon passing over the medial tibial condyle. The clinical, radiologic, and operative findings are reviewed. PMID- 9361922 TI - Grandparent donors in a living related renal transplant program. AB - Clinical renal transplantation is limited by the number of cadaver and living related donors. The use of kidneys from older donors and non-first-degree relatives, including grandparents, has increased the supply of organs for transplantation. The purpose of this study was to assess donor and recipient outcomes after living related renal transplants between grandparent donors and grandchild recipients. Fifteen living related renal transplants using grandparent donors were performed at the University of Minnesota from 1971 to 1995. All medical records from donors and recipients were retrospectively reviewed. In addition, all grandparents or, in one case, a surviving family member were contacted to obtain current information on medical health and feedback about the donation process. A current serum creatinine (Cr) level was obtained from 14 donors and 15 recipients. Statistical calculations were performed using the SAS system. Eleven grandmothers and four grandfathers, 34-70 yr old (mean, 55 yr) at the time of transplantation, donated a kidney to 15 grandchildren with end-stage renal disease. There were no major surgical complications in either group. One donor died from unrelated causes; the other 14 donors are alive with stable renal function (1.3 +/- 0.3 mg/dL). Of 15 transplanted kidneys, 10 remain functional (Cr 1.3 +/- 0.7 mg/dL) with 2- and 5-yr graft survival rates of 76% and 63%, respectively. Our results indicate that healthy grandparents provide an excellent population for living related kidney donation. PMID- 9361921 TI - Graft-versus-host disease after liver and small bowel transplantation in a child. AB - An 8-month-old child with an immunodeficiency disorder characterized by abnormal lymphocyte function and by low IgG and IgA levels had combined liver and small bowel transplantation under tacrolimus and steroid immunosuppression for the treatment of short gut syndrome and hepatic cirrhosis. The patient developed an early postoperative episode of Pneumocystis carinii pneumonia, and a subsequent surgical complication, prompting discontinuance of tacrolimus. A skin rash eventually shown to be graft-versus-host disease (GVHD) developed in the flank on the 12th post-transplant day and gradually became generalized. Peritonitis, sepsis, multisystem organ failure including the liver allograft led to death on the 23rd post-operative day. The mechanisms leading to post-transplant GVHD under the specific circumstances in this case are discussed. PMID- 9361923 TI - Renal outcomes in pediatric liver transplantation. AB - The outcomes of 294 orthotopic liver transplants performed in 221 children at The University of Chicago Children's Hospital between October 1984 and October 1992 have been retrospectively reviewed. Medical information for 281 transplant in 210 children was sufficient for inclusion in this analysis. The mean age at transplant was 4.1 +/- 5.0 yr. Forty-four percent of the children were male, and 16% of the transplants were living-related. Four children received combined liver kidney transplants. Seventy-six percent of the children are currently alive. The incidence of acute renal failure occurring following transplantation and requiring dialysis was 6.2% with a mortality rate of 85%. Early postoperative hypertension was seen in 65% of the children and persistent hypertension of greater than 12 months duration was seen in 28%. Sixteen percent of children developed metabolic acidosis requiring sustained sodium bicarbonate supplementation. Aggregate and longitudinal analysis of serial calculated glomerular filtration rates revealed abnormal renal function in approximately one third of children at any given time period following transplantation. The renal dysfunction was unrelated to age at transplant, type of transplant, gender, previous transplants, rejection episodes, courses of nephrotoxic drugs, presence of hypertension, or cyclosporin dose. This review supports prior studies which document abnormal renal function following orthotopic liver transplantation in a significant proportion of children. PMID- 9361924 TI - Potential for bilateral nephrectomy to reduce oxalate release after combined liver and kidney transplantation for primary hyperoxaluria type 1. AB - Primary hyperoxaluria type 1 (PH-1) is frequently associated with end stage renal failure due to urinary calculi, obstructive uropathy and interstitial deposits of calcium oxalate. The currently accepted treatment for PH-1 is liver transplantation to replace the deficient enzyme peroxisomal alanine glycoxylate aminotransferase (AGT) and a simultaneous renal transplant to restore renal function. The transplanted kidney may become significantly impaired or fail when systemic calcium oxalate is eliminated by renal excretion. The native kidneys are a major source of this oxalate. This study was undertaken to determine whether there is a difference in oxalate clearance following combined liver-kidney transplant in patients with PH-1 by comparing the effect of native kidney nephrectomy at the time of transplantation against leaving the native kidneys in situ. Regression analysis was used to compare daily urinary oxalate excretion corrected for body surface area. There was a significant reduction in urinary oxalate excretion (P < 0.05) in the patient who had undergone bilateral nephrectomy compared to the patient whose native kidneys remained in situ for the first 100 d following combined liver and kidney transplantation. No difference was observed in the serum oxalate levels between patients over the same period or in the renal function assessed by creatinine clearance corrected for body surface area. Total body oxalate load was not determined in this study. A larger study should be undertaken to examine the benefits of nephrectomy in reducing oxalate deposition in recently inserted allografts for patients with PH-1. PMID- 9361925 TI - Significance of the donor age effect on kidney transplants. AB - The shortage of cadaveric donor kidneys for transplantation has forced a re evaluation of the limits on donor age acceptability. However, as more kidneys from older donors have been transplanted, a significantly lower graft survival has been noted among their recipients. The impact of utilizing older donor kidneys and the relative importance of donor age with respect to other factors has not been clarified. A total of 43,172 cadaver donor transplants reported to the UNOS Scientific Renal Transplant Registry between 1987 and 1995 were the subjects of this study. Cox regression analysis was utilized to assess the joint effects on graft survival of donor age and HLA mismatch, recipient sex, race, age, original disease, donor death cause, cold ischemia time, and transplant year. Increased first day anuria, dialysis requirement, and discharge serum creatinine were noted with increasing donor age. Moreover, long-term graft and patient survival diminished as donor age increased. The 5-yr graft survival of zero HLA-A,B,DR mismatched kidneys fell steadily from 81% when the donor was aged 21-30 to 39% when the donor was over age 60. The reported causes of kidney transplant failure were remarkably similar for old and young donors. The best transplant results were obtained with zero HLA-A,B,DR mismatched transplants from young donors and the worst with older donor kidneys, regardless of HLA compatibility. We calculated that up to 21% of kidney failures resulted from insufficient renal mass due to age and were incorrectly attributed to chronic rejection. PMID- 9361926 TI - Poor initial graft function after orthotopic liver transplantation: can it be predicted and does it affect outcome? An analysis of 125 adult primary transplantations. AB - Donor liver shortage is a persistent problem in liver transplantation. A more liberal donor acceptance policy may be a possible solution. However, this might put recipients at risk for initial poor function or even non-function of the graft. Therefore risk factors for initial graft dysfunction should be identified, preferably by using an uniform definition of primary graft dysfunction or non function. We retrospectively analysed 125 adult liver transplantations in order to identify risk factors for initial poor function and primary non-function. Donor, recipient pretransplant and surgical parameters were evaluated. Since there is no consensus on the criteria of dysfunction we used two definitions known from literature. No risk factors for postoperative dysfunction could be identified for either of the two definition sets. Furthermore, the definition set that included ALAT, prothrombin time and bile production in the first 72 h to identify poor graft function showed no relation with graft or recipient outcome. The other set, using ASAT and prothrombin time, determined from day 2 to day 7, showed that patients with a primary dysfunction had significantly higher morbidity and mortality compared to patients with a well functioning graft. We conclude that initial poor function after liver transplantation remains unpredictable, irrespective of the way it is defined. Moreover, our analysis shows that initial poor function can also develop in recipients that receive 'non marginal' grafts without prolonged ischemia times. These results may support a more liberal selection of donor livers. PMID- 9361927 TI - Hepatic arterial complications in pediatric segmental liver transplantations from living donors: assessment with color Doppler ultrasonography. AB - To investigate the clinical utility of color Doppler ultrasonography in detecting hepatic arterial complications in pediatric living-related liver transplantation, we studied peak systolic velocity (Vp) and pulsatility index (PI) intrahepatic artery during and after surgery in 122 transplants. Six cases with hepatic artery thrombosis were detected by Doppler studies. In 2 cases with dampened waveforms at intraoperative flowmetry (Vp < or = 23 and PI < or = 0.6), thrombosis occurred soon after surgery. A further 2 cases had a rapid decrease in Vp and PI values postoperatively, leading to absence of arterial signals. Follow-up Doppler studies suspected collateral formation after thrombosis in 2 survivors. Normal Doppler waveforms were obtained in all of the 116 cases without arterial complications. Among them, 6 cases had absent signals or dampened waveforms at initial intraoperative flowmetry (Vp < or = 30 and PI < or = 0.9), and maneuvers such as re-reanastomosis of the artery improved flow signals with an increase in Vp and PI values. Serial intra- and post-operative Doppler examinations are useful for early detection of arterial complications. PMID- 9361928 TI - Long-term prognosis of renal transplant surviving for over 10 yr, and clinical, renal and rehabilitation features of 20-yr successes. AB - Long-term mortality and morbidity was evaluated in 267 patients with a minimum follow-up of 10 yr and the physical status, graft function and quality of life in 15 patients with a functioning graft surviving for over 20 yr were reviewed. Actual patient and graft survival rates were 80.2% and 51.1% at 10 yr (n = 267) and 56.4% and 32.7% at 20 yr (n = 55), respectively. Although the rate of graft failure due to rejection was 4 times higher than that of patient death within 10 yr, it decreased to the level of patient death in the second decade. Dominant causes of death in patients with graft surviving for over 10 yr were hepatic failure due to viral hepatitis and malignancies. In 15 patients with graft currently surviving beyond 20 yr, while all patients have excellent graft function, malignancy occurred in 5, viral hepatitis in 3, aseptic necrosis in 3, and diabetes mellitus in one patient. No patient has suffered cardiovascular complications. Despite a high rate of morbidity, they show a satisfying status of rehabilitation (full time working 11/ 15, 73.3%). In order to attain more improved QOL in patients with long-term surviving renal transplant, close follow up aiming at diminution of complications is required throughout the period after transplantation. PMID- 9361929 TI - Influence of steroid withdrawal on proteinuria in renal allograft recipients. AB - The ratio of urine protein/urine creatinine in spot urine specimens was measured to determine the influence of steroid withdrawal and other clinical variables on urinary protein excretion in 135 primary renal transplant recipients, including 73 patients in whom steroid withdrawal was never attempted and 62 patients in whom steroid withdrawal was attempted at various times following transplantation. Both univariate and multivariate analyses showed that steroid withdrawal per se did not directly influence proteinuria. However, patients who renewed steroid therapy because of acute allograft rejection following attempted steroid withdrawal exhibited significantly more proteinuria than was encountered either in patients who remained steroid-free or in those for whom steroid withdrawal was never attempted. This study suggests that steroid withdrawal itself does not lead to proteinuria, however, acute rejection following steroid withdrawal clearly accelerates urinary protein excretion that may be the harbinger of chronic allograft rejection. PMID- 9361931 TI - Vulnerability to psychologic distress and depression in patients with end-stage liver disease due to hepatitis C virus. AB - Psychosocial sequelae and quality of life impairment in patients with end-stage liver disease due to hepatitis C virus (HCV) are not known. Quality of life, psychological distress (Profile of Mood State scale), depression (Beck Depression Inventory), and coping (Ways of Coping scale) were prospectively assessed in 82 liver transplant candidates; comparisons were made between patients with HCV hepatitis versus patients with other liver diseases. Patients with HCV were significantly younger than all other patients (p = 0.002). Total mood disturbance (p = 0.038), tension and anxiety (0.047), confusion and bewilderment (p = 0.035) and depression and dejection (p = 0.035), as assessed by Profile of Mood States Scale were significantly higher in patients with HCV than other patients. Patients with HCV were significantly more depressed as assessed by Beck Inventory scores (p = 0.014). Karnofsky performance scores, Child-Pugh score, and liver function tests were not significantly different for patients with HCV vs. all other patients. However, somatic manifestations of the illness (e.g. pain) were greater in patients with HCV and may have contributed towards greater depression in these patients. Our findings warrant replication in other studies, since depression is a modifiable and treatable disorder. PMID- 9361930 TI - Efficacy and side-effects of cyclosporine dose monitoring with levels 6 h after the morning dose in heart transplant patients. AB - The purpose of this study was to compare CsA dose monitoring with trough levels (T0) vs. levels obtained 6 h after the morning dose of CsA (T6), with respect to the incidence of acute rejection and renal dysfunction, and the cumulative dose, as well as the cost of CsA after heart transplantation. Twenty consecutive adult heart transplant patients receiving quadruple sequential immunosuppression were prospectively randomized into CsA monitoring with T0 (Group I) vs. T6 levels (Group II). Oral CsA was started at a dosage of 2 mg/kg/d, 1-4 d after transplantation. The target range for either T0 or T6 was 150 to 250 ng/ml (enzyme multiplied immunologic technique), respectively. The CsA dose was increased or decreased by 0.5-1 mg/kg/d if the measured level was outside of the target range. Throughout the follow-up period (Group I, 11 +/- 2 months; Group II, 10 +/- 3 months), the incidence of acute rejection (ISHLT grade > or = 2) was 50% in each group. The left ventricular ejection fraction and serum creatinine were similar in both groups at 1 month and at the end of the follow-up. The maximal dose of CsA (mg/kg/d): 3.8 +/- 1 vs. 5 +/- 0.6 (P = 0.002), the minimal dose: 2.2 +/- 0.7 vs. 3.4 +/- 0.8 (P = 0.003), and the current dose: 2.6 +/- 0.6 vs. 3.5 +/- 1 (P = 0.02), were lower in Group II, as well as the cumulative dose of CsA (mg): 61,790 +/- 19,754 vs. 88,524 +/- 18,082 (P = 0.005), and its cost (CDN$): 3,589 +/- 1,116 vs. 5,106 +/- 1,045 (P = 0.005). In conclusion, CsA dose monitoring with T6 was associated with a 30% lower CsA dose and cost compared to T0, with the same effectiveness in the prevention of acute rejection, and similar cardiac and renal function. PMID- 9361932 TI - Evaluation of neurotoxicity in pediatric renal transplant recipients treated with tacrolimus (FK506). AB - The presence of severe and mild neurotoxicity in our pediatric renal transplant recipients treated with tacrolimus was determined by chart review (severe neurotoxicity) and patient survey (mild neurotoxicity). 14 patients were studied (mean age 15 yr, 5 month, +/- 4.4 yr). 1 patient experienced seizures, felt to be related to malignant hypertension. No other episode of severe neurotoxicity was documented. Most patients (12/14) reported at least one mild neurologic symptom, and half stated their symptoms were present at least 'most of the time'. The most frequent complaints were myalgias (7/14, 50%) and tremors (7/14, 50%) followed by fatigue (5/14, 38%). Severe neurotoxicity may be relatively infrequent in pediatric renal transplant patients treated with tacrolimus. Milder neurologic complaints may be commonly seen in this population, but in general are not severe enough to cause discontinuation of tacrolimus. PMID- 9361933 TI - Assessment of long-term risks for living related kidney donors by 24-h blood pressure monitoring and testing for microalbuminuria. AB - Our aim was to assess the long-term risks for kidney donors of developing arterial hypertension and hypertension-associated diseases or hyperfiltration injury of the remaining solitary kidney. We conducted a cross-sectional study in which 29 donors who were nephrectomized at our center between October 1973 and March 1990 were enrolled. At the time of evaluation median age was 54 (37-70) yr. Since kidney donation an average time interval of 11.1 +/- 3.8 yr had elapsed. Body weight, casual blood pressure, S-creatinine and proteinuria were recorded. In 28/29 donors 24-h blood pressure monitoring was performed; all 29 were tested for microalbuminuria (MAU). The patient history was checked for treatment with antihypertensives, coronary heart disease and diabetes mellitus. From all 29 kidney donors surveyed up to 19.8 yr none developed marked renal insufficiency: median S-creatinine was 1.0 mg/dl (range 0.7-1.6), only 3 donors had a S creatinine > 1.3 mg/dl. Glomerular filtration rate (GFR) decreased in an age dependent manner. While all donors had been normotensive without an antihypertensive treatment at time of nephrectomy, actually 29% proved to be hypertensive with average values > 130/80 mmHg in the 24-h assessment. 5/29 donors received antihypertensives, 3 of whom nevertheless were hypertensive. Day night profile was lost in 2 patients. After donation one patient developed coronary heart disease. 7/29 donors (24%) displayed positive testing for MAU, furthermore one had proteinuria (approx. 300 mg/l). MAU was associated in one case with slightly elevated S-creatinine (1.3 mg/dl) and in 3 cases with arterial hypertension. In the long-term course living related kidney donors do not seem to be at risk for developing hypertensive disorders more often than the general population. The prevalence of MAU in the 29 cases studied was higher than so far described for healthy subjects. This may reflect subclinical hyperfiltration damage of the glomerulus. Progressive renal insufficiency with clinical relevant function loss of the remaining solitary organ, however, was not observed up to 19.8 yr after kidney donation. PMID- 9361935 TI - Role of endomyocardial biopsy in the diagnosis of chronic rejection in human heart transplantation. AB - To assess the pathologic findings observed in the setting of post-transplant graft atherosclerosis, we have studied 18 endomyocardial biopsies (EMB) from 18 heart-transplanted patients collected at the same time that a coronary angiography (CA) showed changes consistent with graft atherosclerosis. Twenty-two EMB from patients with heart transplant with normal CA were used as controls. In spite of the small size of the sample, the number of acute rejection (AR) episodes correlated with the appearance of graft atherosclerosis (p < 0.001). Heart biopsies in graft atherosclerosis showed myointimal proliferation, thickening and folding of the wall of precapillary arteries, myocyte hypertrophy, and interstitial and perivascular fibrosis. Type III and type IV collagen, laminin, and fibronectin were increased in areas of interstitial and perivascular fibrosis, as well as in the vessel's wall. Fibronectin accumulation was more evident in the subendothelium and inner media of affected vessels. These changes were never found all together in control biopsies. Even though the inespecificity of some of those findings, we conclude that chronic graft atherosclerosis in a heart transplant may be suspected by endomyocardial biopsy when most of these alterations are seen together, especially if small precapillary arteries are present in the specimen. PMID- 9361934 TI - Preservation of pancreatic endocrine function by hemodynamic stabilization following brain death. AB - A protocol achieving for long-term hemodynamic stability enabled us to evaluate pancreatic endocrine function for up to 1 wk following brain death. The glucose disappearance rate was significantly lower in brain-dead patients (N = 21) than in normal controls (N = 10) (p < 0.001). In 19 brain-dead patients whose plasma epinephrine concentrations exceeded 0.4 ng/ml, the mean early insulin release was significantly lower than in controls, while early insulin release was markedly higher in the remaining two patients. It is possible that early insulin released may be due to increased plasma epinephrine concentrations following brain death. Late insulin release in brain-dead patients was not lower, but was higher than controls and was accompanied by a decrease in the glucose disappearance rate. No evidence of abnormalities in histopathology of pancreas was detected at autopsy. Our results indicate that intrinsic insulin secretory function can be preserved during the first week following brain death. PMID- 9361936 TI - Cytomegalovirus immune globulin (CMVIG) prophylaxis is associated with increased survival after orthotopic liver transplantation. The Boston Center for Liver Transplantation CMVIG Study Group. AB - Cytomegalovirus (CMV) causes considerable morbidity and mortality in orthotopic liver transplant (OLT) recipients. Several prophylactic strategies against CMV have been studied in solid organ transplant recipients, including cytomegalovirus immune globulin (CMVIG). We examined the effect of CMVIG prophylaxis on first year and long-term survival after liver transplantation. Data were analysed for 162 OLT recipients from four transplant centers in Boston who participated in two CMVIG prophylaxis trials. Ninety patients received CMVIG (median follow-up 5.6 yr), and 72 patients received placebo (median follow-up 5.4 yr). CMVIG prophylaxis was shown to be associated with increased first-year (86% vs. 72%, p = 0.029) and long-term (68% vs. 54%, p = 0.055) survival. The distribution of baseline characteristics including donor and recipient demographics, donor CMV serostatus, United Network for Organ Sharing (UNOS) status, pre-transplant renal and liver function tests, transplantation surgical time, number of units of blood products administered during transplantation, primary immunosuppressive regimen, use of solumedrol or antilymphocyte therapy for induction of immunosuppression or treatment of rejection, and surgical complications was similar for CMVIG and placebo recipients. CMVIG recipients were more likely to have primary biliary cirrhosis than placebo recipients (21% vs. 8%, p = 0.025). Using a Cox proportional hazards multivariate model to control for pre-transplant liver disease, CMVIG was shown to be independently associated with increased first-year survival (p = 0.042); a trend toward association with increased long-term survival (p = 0.098) was also shown. These data support that CMVIG prophylaxis, beyond its proven efficacy in decreasing the incidence of severe CMV-associated disease, is associated with increased survival when used prophylactically in OLT recipients. PMID- 9361937 TI - Thrombocytopenia in an established solitary pancreas graft recipient. AB - Isolated, life-threatening thrombocytopenia from a previously well tolerated pancreas allograft has not been reported in the literature. Herein we report such a case where a 31-year-old, Caucasian, Type I diabetic male developed severe thrombocytopenia 6 months following isolated pancreas transplantation and 2 wk after enteric conversion of the graft. Despite extensive diagnostic work-up, the cause remained unclear and his thrombocytopenia did not remit with standard treatment, but did resolve upon explantation. Pathologic examination of the pancreatic graft showed evidence of chronic rejection along with CMV pancreatitis. We conclude that unremitting isolated thrombocytopenia in solitary pancreas grafts may reflect a localized DIC phenomenon that requires graft explantation. PMID- 9361938 TI - Equivalence of cyclosporine blood level assays in patients receiving cyclosporine microemulsion or cyclosporine. The Sandoz Neoral Study Group N103. AB - The more rapid absorption of the cyclosporin A (CyA) microemulsion formulation (Neoral, NEO) compared to Sandimmune (SIM) might bypass intestinal metabolism resulting in differing amounts of CyA metabolites in blood as compared to SIM. If true, then CyA levels obtained with a CyA monoclonal antibody assay (TDx) that has metabolite cross-reactivity might differ depending on the CyA formulation received by the patient, thereby affecting safety and efficacy. Fifty-one NEO vs. 50 SIM treated de novo renal transplant recipients from a multicenter double blind randomized trial had morning, whole-blood, trough-samples obtained at the ends of weeks 1, 4, 8, and 12 post-transplant assayed for CyA by HPLC and TDx. The slopes (ratio of TDx value to HPLC value) for the regression lines between TDx and HPLC levels as a function of time post-transplant and CyA formulation were determined using a general linear model. For NEO, the slopes at each week (1.21-1.41 x HPLC) did not differ significantly (p = 0.82). For SIM, the week 1 slope (1.2) was significantly (p = 0.006) less than the other weeks (1.4-1.44). The slopes (NEO vs. SIM) were not different at either week 1 (1.21 vs. 1.22, p = 0.82) or at pooled weeks 4, 8, and 12 (1.33 vs. 1.4, p = 0.1). These results indicate that despite the improved absorption, TDx values obtained on NEO are qualitatively similar to those obtained on SIM. PMID- 9361939 TI - Use of ciprofloxacin as a prophylactic agent in urinary tract infections in renal transplant recipients. AB - The most common form of bacterial infection in renal transplant recipients is urinary tract infection (UTI), and some studies have shown that prophylaxis can reduce this incidence. In the present investigation we evaluated 80 patients submitted to renal transplantation at the Renal Transplant Unit of the University Hospital of Ribeirao Preto, SP. The study was prospective, double blind and randomized. The patients were divided into two groups, one receiving placebo and the other ciprofloxacin at the dose of 250 mg twice a day for the first 10 d and 250 mg/d for 6 months after transplantation. Of the 41 patients who received ciprofloxacin 28 completed the study, and of the 39 patients who received placebo 30 completed the study. The largest number of UTI occurred in the placebo group, with a significant difference from the ciprofloxacin group during the first month after surgery (p < 0.05). In the group treated with ciprofloxacin, only 6/40 patients (15%) developed UTI, as opposed to 19/39 (48.7%) for the placebo group. The total number of infectious episodes was higher in the placebo group (26) than in the ciprofloxacin group (12). The medication was well tolerated throughout the study period. PMID- 9361940 TI - Orthotopic liver transplantation for adult-onset type II citrullinaemia. AB - Citrullinaemia is a rare autosomal recessive disorder due to a deficiency of argininosuccinate synthetase (ASS). While the clinical course of the adult onset form (Type II) is unpredictable, many patients undergo sudden deterioration with progressive cerebral oedema. Two patients with Type II citrullinaemia were referred for liver transplantation. One patient was successfully transplanted, and his plasma citrulline level decreased from 300 to 69 mumol/l (normal range 20 60 mumol/l); Fisher's ratio increased to a normal range within 24 h of transplantation. The other patient died from cerebral oedema, despite Optimal pharmacological measures, while awaiting a suitable donor organ. Dietary and pharmacological treatment is vital before liver transplantation. The level of serum arginine requires regulation, as it can rise secondary to citrullinaemia in Type II disease. An immunocytochemical study of the liver in both patients showed a clustered distribution of ASS which is associated with a dismal prognosis compared with patients who have a homogenous distribution. Distribution of ASS was normal in the transplanted liver. Liver transplantation is effective therapy for adult-onset Type II citrullinaemia. A clustered pattern of ASS distribution in a liver biopsy is a significant feature to activate early referral for liver transplantation. PMID- 9361941 TI - Iliac reconstruction with arterial allograft during pancreas-kidney transplantation. AB - An intraoperative dissection of the external iliac artery during pancreas transplantation was successfully repaired using the donor iliac artery allograft as a conduit between the internal iliac and distal external iliac artery. An angiogram performed 6 months after surgery showed a patent bypass without stricture or pseudoaneurysm. At 1 yr follow-up after transplant the grafts are functioning well, and the affected extremity is normal. In immunosuppressed recipients of solid organ transplants, fresh arterial allografts may be successfully used for iliac artery reconstruction. Further study will be needed to determine the role of arterial allografts for lower extremity bypass surgery in immunosuppressed patients. PMID- 9361942 TI - Coronary artery bypass after single lung transplant: a case report. AB - Chronic obstructive pulmonary disease (COPD) is the most common indication for adult single lung transplantation. These patients commonly have one or more risk factors for coronary artery disease. Traditionally previous lung transplantation has been considered a contraindication to coronary artery bypass grafting (CABG). This report describes a case of CABG 3 yr after single lung transplantation and briefly discusses the risks of cardiac surgery in lung transplant patients. PMID- 9361943 TI - Effect of race on outcome following kidney and kidney-pancreas transplantation in type I diabetics: the South-Eastern Organ Procurement Foundation experience. AB - In this study we analyze the South-Eastern Organ Procurement Foundation (SEOPF) experience with kidney and kidney-pancreas transplantation in IDDM recipients and evaluate the impact of racial disparity on patient and graft outcome. Data obtained from 4413 kidney-alone and 884 pancreas transplants performed in White and Black type I diabetics at member institutions of SEOPF between 10/1/87 and 7/25/96 were analyzed. Survival data from 15,827 transplants performed during the same period of time in non-diabetics were available for comparison. A lesser proportion of pancreas recipients were Black compared to kidney-alone (12% vs 23%, p < 0.0005). Recipient race had no effect on patient survival in any of the groups studied. Kidney graft survival, on the other hand, was adversely affected by Black race in both non-diabetic and diabetic recipients of a kidney transplant but not in diabetics who received a combined pancreas-kidney transplant. As was the case for patient survival in diabetics, recipient race had no effect on pancreas graft survival. Cox Regression analysis showed that kidney-pancreas transplant (p = 0.034, RR = 0.49) and female recipient gender (p = 0.046, RR = 0.68) were associated with a lower risk of failure of the pancreas graft. The following factors were independent predictors of kidney graft outcome: Donor age (p = 0.0001, RR = 0.95), kidney-pancreas transplant (p = 0.0004, RR = 0.58), AB match (p = 0.001, RR = 0.86), DR match (p = 0.006, RR = 0.82), preservation time (p = 0.012, RR = 1.01), Black recipient race (p = 0.047, RR = 1.23) and living donor (p = 0.06, RR = 0.73). Our findings suggest that the effect of race on graft outcome observed in non-diabetic and, to a lesser extent, diabetic kidney alone transplant recipients, is not present after kidney-pancreas transplantation. PMID- 9361944 TI - Hepatitis antigenemia and survival after renal transplantation. AB - Some transplant programs regard hepatitis B antigenemia (HBsAg+) as a contraindication to renal transplantation. We studied the records of 13,287 renal transplant recipients, 781 (5.88%) who were positive for HBsAg, the remainder negative (HBsAg-). Patient survival for HBsAg-recipients is 91.8% at 1 year, 80.6% at 5 years, and 65.8% at 10 years. Patient survival for HBsAg+ recipients was 88.8% at 1 year, 77.6% at 5 years, and 61.6% at 10 years. The difference in patient survival was 3-4%, and graft survival was nearly constant at 3%. The statistical significance for patient survival was p = 0.02 by the log-rank test and p = 0.007 by the Wilcoxon test. There is far more statistical power (p = 0.0001) in other risk factors such as transplant number, recipient race, recipient age, and diabetes. Currently available diagnostic studies may allow better risk stratification of HBsAg+ candidates. We believe that hepatitis antigenemia without added and related risk factors has only a mild effect on graft and patient outcome. PMID- 9361945 TI - HLA-DQ matching in cadaveric renal transplantation. AB - The impact of matching for the human leukocyte antigen (HLA)-DQ phenotype in cadaveric renal transplantation is unclear. We analyzed the effect of matching serologically defined HLA-DQ phenotypes on renal allograft survival in 12,050 first cadaveric renal transplants (recipients were 63.5% white and 36.5% African American). Recipients were entered into the South-Eastern Organ Procurement Foundation (SEOPF) database between 1 October 1987 and 6 June 1995. A series of life table analyses were done to test the equality of survival curves for HLA-DQ match, both alone and accommodating for differences in recipient race and HLA-DR match. Cox regression models were then performed to detect differences in allograft survival based upon HLA-DQ match. Initial adjustments were done by recipient race. Subsequent adjustments were done by recipient and donor race, age and sex, cold ischemia time (CIT), body mass index (BMI), cyclosporine A (CyA) use, peak panel reactive antibody (PRA) titer, year of transplant, presence of diabetes mellitus (DM), and degree of HLA-A,B and HLA-DR match as covariates. The effect of varying degrees of HLA-DQ match on graft survival were similar between the two races (p = 0.87). In all recipients, an 8.3% reduction in graft failure was observed for each increase in HLA-DQ match using the Cox regression model adjusted only for recipient race (p = 0.004). A non-significant 3.0% reduction in graft failure (p = 0.38) was observed for each level of increasing HLA-DQ match when using the Cox regression model adjusted for recipient and donor race, age and sex, CIT, BMI, CyA use, year of transplant, DM, HLA-A,B and -DR match. In this model, superior HLA-A,B match and HLA-DR match, recipient and donor age, male donor sex, shorter CIT, white race of recipient, lower peak PRA, CyA use, and absence of DM significantly improved graft survival (all < or = 0.004). We conclude that HLA-DQ matching does not significantly affect cadaveric renal allograft survival once adjusted for other known predictors of graft outcome. PMID- 9361946 TI - The significance of the IgG anti-B-cell crossmatch on renal transplant outcome. AB - Transplantation in the presence of anti-class I antibodies usually results in allograft hyperacute rejection. Because of the perception of its uncertain clinical significance, B-cell crossmatch which identifies presence of anti-class II antibodies is not universally performed. In a retrospective study, the clinical course of renal transplant recipients with IgG anti-B-cell antibodies was analyzed and compared with case control patients transplanted contemporaneously, matched demographically and immunologically. The incidence of hyperacute, acute, and chronic rejection as well as graft loss were significantly higher in the group with anti-IgG B-cell antibodies compared to the control. We conclude that anti-B-cell IgG antibodies are harmful to allografts with a spectrum of events that include hyperacute, acute, vascular and chronic rejection. While allografts were successful in some patients, our experience suggests caution whenever anti-donor B-cell IgG is present. If transplants are performed, then more potent immunosuppression should be used. PMID- 9361947 TI - Regional organ procurement (ROP) trays in renal allograft distribution and outcome. AB - ROP trays containing patient serum samples and distributed by the South-Eastern Organ Procurement Foundation (SEOPF) were instituted to increase the likelihood of transplanting potential renal recipients who are highly sensitized to HLA antigens. This study examines kidney distribution and transplant outcome to assess equitable placement and clinical function post transplant with and without the use of ROP trays. Data were collected over a 26-month period on the distribution of kidneys from 328 consecutive SEOPF donors from whom at least 1 kidney was procured. Shared kidneys were placed via the UNOS and SEOPF-variance computer match programs. Of 656 kidneys, 596 were placed into 582 recipients; 60 were not used. ROP trays were used in placement of 492 kidneys and were not used for placement of 104 kidneys. Outcome was determined for 435 kidneys transplanted into SEOPF recipients. Only 33 (6.9%) recipients with ROP tray use and 10 (9.8%) without were sensitized to HLA. A 10% increase in placement to the originally intended recipient was seen with ROP tray usage over kidneys placed without ROP tray use (p < or = 0.025). Recipients matched using ROP tray data averaged 29 positions higher on the match printout. There was no difference in tray use regarding placement of kidneys within or outside the donor's local UNOS region, nor was there a difference in mean HLA match of transplant pairs with and without ROP tray use, 3.2 and 3.1 antigens, respectively. Cold ischemia time was similar, 22.9 and 23.6 h, respectively, for kidneys placed with and without ROP trays. At post-transplant discharge, there were no differences in patient status, graft failure, rejection treatment, dialysis need, or urine output whether or not ROP trays were used. Significantly, however, plasma creatinine at discharge and at 12 months was lower for those placed with ROP trays (2.5 mg/dl and 1.7 mg/dl) vs (3.1 mg/dl and 1.9 mg/dl), respectively. During this time period, all kidneys transplanted with use of ROP trays functioned as well or better than those transplanted without ROP tray placement. Thus, the use of ROP trays appeared to have a beneficial effect in getting more recipients of higher priority transplanted with equivalent, if not better, graft function. PMID- 9361949 TI - The use of tacrolimus as induction and maintenance immunosuppression in renal cadaveric transplant recipients over the age of 60. AB - Renal transplantation is a treatment option that should be considered for the elderly (> or = 60 years old) with end-stage renal disease. Little is known regarding the use of tacrolimus (as induction and maintenance immunosuppression) in this age group. We report the outcome of kidney transplantation in 21 patients aged 60 years or more with tacrolimus. During the past few years in kidney transplant maintenance immunosuppressive regimens, we have revised our standard general protocol from cyclosporine to tacrolimus-based therapy for maintenance immunosuppression and for rescue therapy. We also introduced mycophenolate (RS 61443) while we have continued to use ATGAM/OKT3 as induction regimen in the immediate postoperative period. We treated these renal recipients with tacrolimus and steroids in combination with azathioprine or mycophenolate mofetil without antibody induction. This was well tolerated and not associated with a higher rate of rejection (20%) whereas the potential toxicity of antilymphocyte preparations was avoided. PMID- 9361948 TI - The impact of pre-transplant obesity on renal transplant outcomes. AB - The impact of obesity on graft survival after renal transplantation continues to be controversial. We have reviewed our experiences with living donor and cadaver transplantation in the current decade, focusing specifically on the impact of obesity on transplant outcome. Preoperative body mass index (BMI, kg/m2) was calculated for all adult renal transplant recipients between January 1990 and December 1995 and was used to classify patients as non-obese, moderately obese or morbidly obese. The effect of the degree of obesity on early and late outcomes after renal transplantation was examined. Three hundred and thirty-three recipients had pre-transplant BMI < 30 (normal or mild obesity), 68 BMI 30-40 (moderate obesity), and 7 BMI over 40 (morbid obesity). There was no correlation between obesity and other demographic factors. Wound infections and delayed graft function occurred more commonly in moderately and morbidly obese than in other cadaver donor recipients. Obese patients gained more weight after surgery and were given lower doses per kilogram of cyclosporine. There was, however, no significant correlation between obesity and graft survival for either cadaver or living donor transplants. Although obese patients have an increased risk of delayed graft function with cadaver donor transplantation, obesity has no discernible impact on either immunologic or overall graft survival with cadaver or living donor transplantation. The impact of moderate obesity on transplant outcome is modest and should not prevent these patients from receiving a transplant. PMID- 9361950 TI - Steroid withdrawal in kidney transplant recipients: is it a safe option? AB - The long-term side effects of lifelong steroid immunosuppression are well documented, therefore, steroid withdrawal (SW) if safe would clearly be of benefit. From 1987-1996, 470 kidney transplants were performed at our institution. During this time period, steroid withdrawal was offered to a select group of patients (n = 43) who were at least 1 year post transplant (27.6 +/- 12.0 months, 15-64 months), had stable graft function and had experienced only mild episodes of rejection in the postoperative period. Informed consent was obtained from all participants. Twenty-five patients were male and 18 were female. The mean age at time of transplantation was 42.4 +/- 14.1 years (17-65 years). There were 28 cadaveric renal transplants (CRT), 10 living related kidney transplants (LRT) and 5 simultaneous kidney-pancreas transplants (SPK). Maintenance immunosuppression in all patients consisted of CSA 3-5 mg/kg, and AZA 1-2 mg/kg. Twenty-nine patients (67%) have remained off steroids with good renal function for 13-59 months (38.3 +/- 11.0). Steroids were restarted in 14/43 (32%) patients 1-36 months post SW (13.3 +/- 11.0 months). Eight of these 14 patients had a rise in creatinine and biopsy proven rejection, 5 of whom responded to reinstitution of steroid immunosuppression, and have stable renal function (CR = 2.0 +/- 0.4) 41-53 months (45 +/- 4.0 months) post SW. Three (7%) patients lost their allograft. One was a SPK recipient who retained good pancreatic function and subsequently received a successful 2nd kidney transplant. The other 2 patients died awaiting retransplantation. Steroids were recommenced in 6/14 patients who did not develop rejection for inability to tolerate CSA/AZA (2), anxiety (2) or recurrent disease (2). In the majority of our patients, (93%) SW did not result in immunologic graft loss. A graft loss of 7% (3) is not significantly different from the expected graft loss in a kidney transplant recipient population over a time period of 9 years. Therefore, we feel that with careful monitoring steroid withdrawal can be safely accomplished in select patients. PMID- 9361951 TI - Current issues in living donor nephrectomy. AB - Of 96 consecutive renal transplants in 2 years, 50 (52%) were living donor grafts. Donor demographics, treatment plans, length of stay (LOS), charges, and complications were reviewed. Donors included 27 women and 23 men aged 22 to 61 (mean 42.2) years; 33 were living related and 17 living unrelated donors. Racial distribution included 1 Hispanic, 2 Asian, 8 black, and 39 white donors. Pretransplant evaluation defined renal anatomy and function (minimal creatinine clearance 75 cc/min). Hospital admission occurred the morning of donation. Nephrectomy under general anesthesia entailed an anterior flank, extra retroperitoneal approach (no rib resection); and postoperative epidural pain control was standard. Progressive early ambulation and pulmonary self-care optimized recovery. The 50 donors were hospitalized for 2 (n = 7), 3 (n = 18), 4 (n = 15), 5 (n = 6), and 6-8 (n = 4) days (mean LOS: 3.74 +/- 0.17, range 2-8 days). The mean charge for donor hospitalization was $15,415 +/- $397 (range $10,808-$29,579). One major intraoperative hemorrhage required transfusion; 1 patient was readmitted for wound drainage and pneumonia treated medically. While 40 of 50 patients (80%) were hospitalized for 4 days or less, there was no readmission because of short hospital stay. One early graft loss (3 days) occurred from technical problems; all others gained excellent life sustaining function. Three additional kidneys failed from rejection, noncompliance, and systemic coagulopathy. One recipient died at 8 months (CVA) with normal renal function. Current strategies for successful living kidney donation are thorough patient and family education, ambulatory preoperative testing, morning of surgery admission, and discharge planning beginning before hospitalization. Excellent outcomes may be accompanied by a brief LOS, epidural pain management, and liberal use of willing and healthy related and unrelated living donors. PMID- 9361952 TI - Hepatic ischemia/reperfusion affects leukocyte rolling and velocity. AB - Mechanisms of injury in hepatic ischemia/reperfusion injury are poorly defined. Leukocytes are thought to be important in the final mechanism of hepatic damage. We intend to show the time course of abnormal leukocyte activity in the liver after ischemia/reperfusion (I/R) injury. Left lobar hepatic ischemia was induced for 20 min in anesthetized C57B1-6 mice. Measurements were taken at control, reperfusion, and matching sham times (no ischemia) of 2, 5, 12, and 24 h. Measurements were taken using rhodamine and fluorescein enhanced intravital microscopy. Post sinusoidal venules were evaluated for numbers of rolling leukocytes, leukocyte saltation, and leukocyte velocity. Data are expressed as number of rolling leukocytes per 100 microns venule length (2 min). Statistical analysis was by ANOVA. The number of rolling leukocytes at 5, 12, and 24 h of reperfusion (p < 0.001) was significantly higher than control and sham-operated animals. Leukocyte velocities were significantly slower in the 12 h I/R group when compared to sham animals (p < 0.001). These data show that there are definable and quantifiable changes in leukocyte kinetics in the liver after ischemia/reperfusion. These changes, which lasted for 24 h, are likely due to upregulation of various endothelial cell adhesion molecules. Delineation of these mechanisms may be important in disease states such as shock, sepsis, and hepatic transplantation. PMID- 9361953 TI - The role of CD11b/CD18 mediated neutrophil adhesion in complement deficient xenograft recipients. AB - Hyperacute rejection (HAR) of discordant xenografts is dependent on local complement activation. The formation of a functional complex of the complement components C5b-9 (membrane attack complex, MAC) causes endothelial injury and activation leading to coagulation and inflammation. In PVG rats which selectively lack the C6 component of complement, the MAC complex is not formed, whereas early split products of the complement cascade are produced normally. We reported previously that HAR is averted in C6 deficient xenograft recipients, and that subsequent accelerated acute rejection (AAR) can be delayed by inhibition of CD11b/CD18 (Mac-1) dependent neutrophil adhesion using leumedin, a member of a novel class of anti-inflammatory agents. Here we report the in vivo effects of a dose-response study using 2 new members of another class of Mac-1 directed agents designated nactins. Discordant cardiac xenografts from Hartley guinea pigs were heterotopically grafted into PVG(C6-) and PVG(C6+) rats. Experimental animals were divided into 3 groups receiving leumedin (group 1) or nactin (groups 2 and 3). Control animals received intravenous saline solution only. All C6(+) rats rejected their grafts hyperacutely within 10 to 15 min, irrespective of mode or dosage of treatment. C6 deficient controls rejected grafts within 17.7 +/- 3.5 h (n = 10). Treatment with leumedin/nactin prolonged graft survival up to 61.0 +/- 4.7 h (n = 4-6), with dose dependent differences in effectiveness among the 3 compounds tested. Histology showed that treatment was associated with less edema, hemorrhage, and neutrophil infiltrate at 2, 6, and 12 h. The marked decrease in hemorrhage seen in nactin-treated animals may reflect an interaction of Mac-1 with blood coagulation factors. Our data confirm that the neutrophil adhesion pathway is involved in AAR, especially when complement mediated injury due to MAC is restricted. PMID- 9361954 TI - A model of human anti-T-cell monoclonal antibody therapy in SCID mice engrafted with human peripheral blood lymphocytes. AB - A chimeric severe combined immunodeficient mouse engrafted with human peripheral blood (hu-PBL-SCID) model has been developed to test anti-T-cell monoclonal antibody (mAb) effects on systemic symptoms of the host and the survival of human skin grafts. To obtain consistent engraftment without lethal acute graft-versus host disease (GVHD), SCID mice were pretreated with a combination of total body irradiation (2.5 Gy, day 0) and anti-asialo GM1 (anti-mouse natural killer cell) antiserum (50 micrograms i.p., day 3) before the intraperitoneal injection of 40 50 X 10(6) human PBL on day 4. With this protocol, the engraftment rate was 82% with 5-98% human CD45-positive cells in the peripheral blood. Mortality at 30 days was 0% in the mice bearing 5-50% human cells compared with 70% in those with more than 50%. Using hu-PBL-SCID mice with 5-50% human cells in their peripheral blood, we demonstrated the following results: 1) Human T cells isolated from these mice proliferated in response to immobilized OKT3 stimulation in vitro. 2) Hu-PBL-SCID mice but not normal SCID mice were able to reject human skin grafts in vivo 16-21 days after grafting. 3) Both OKT3 (anti-human CD3 mAb) and T10B9 (anti-human alpha beta T-cell receptor mAb) treatment prevented human skin graft rejection in hu-PBL-SCID mice. 4) OKT3 but not T10B9 induced first dose reactions characterized by hypothermia and hypoactivity which were consistently observed within 90 min of intravenous injection into hu-PBL-SCID mice. 5) Human cytokines were detected in the serum of the hu-PBL-SCID mice treated with anti-T-cell mAbs. The close similarity of these responses to human clinical mAb immunosuppressive therapy suggests that the hu-PBL-SCID mouse model may be an excellent tool for investigating the immunosuppression, side effects, and mechanism of action of agents that are specific for human and higher apes and not reactive with lower animals. PMID- 9361955 TI - Anthracyclines in the treatment of cancer. An overview. AB - Anthracyclines are widely used and effective antineoplastic drugs. Although active against a wide variety of solid tumours and haematological malignancies, their clinical use is hindered by tumour resistance and toxicity to healthy tissue. Modification of the general anthracycline ring structure results in analogues with different but overlapping antitumour and tolerability profiles. Activity of the anthracyclines is related to topoisomerase II inhibition, which occurs as a result of anthracycline intercalation between adjacent DNA base pairs. Production of hydroxyl free radicals is associated with antitumour effects and toxicity to healthy tissues. Myocardial tissue is particularly susceptible to free radical damage. Development of tumour cell resistance to anthracyclines involves a number of mechanisms, including P-glycoprotein-mediated resistance. The classical dose-limiting adverse effects of this class of drugs are acute myelosuppression and cumulative dose-related cardiotoxicity. Anthracycline induced cardiomyopathy is often irreversible and may lead to clinical congestive heart failure. Other toxicities of the anthracyclines, including stomatitis, nausea and vomiting, alopecia and 'radiation recall' reactions, are generally reversible. Anthracycline-induced cardiotoxicity may be reduced or prevented by an administration schedule that produces low peak plasma drug concentrations. Administration of dexrazoxane also provides cardioprotection. Dose intensification of anthracyclines may partly overcome resistance but is associated with reduced tolerability. Liposomal encapsulation of doxorubicin or daunorubicin alters the pharmacokinetic properties of the drugs. Increased distribution in tumours, prolonged circulation and reduced free drug concentrations in plasma may increase antitumour activity and improve the tolerability of the anthracyclines. PMID- 9361956 TI - Liposomes. Opportunities in drug delivery. AB - Liposomal drug delivery systems markedly alter the biodistribution of their associated drugs by delaying drug clearance, retarding drug metabolism, decreasing the volume of distribution, and shifting the distribution in favour of diseased tissues with increased capillary permeability. This increases the therapeutic indices of the associated drugs, by increasing the drug concentration in solid tumours and regions of infection, and reducing the drug concentration in normal tissues. Three liposomal formulations have been approved for clinical use. PMID- 9361957 TI - Polyethylene glycol-coated (pegylated) liposomal doxorubicin. Rationale for use in solid tumours. AB - Polyethylene glycol (PEG)-coated (pegylated; Stealth) liposomes are stable, long circulating drug carriers useful for delivering doxorubicin to the sites of solid tumours. Compared with conventional liposomes, pegylated liposomes are less extensively taken up by cells of the reticuloendothelial system (RES) and have a reduced tendency to leak drug while in circulation. The pharmacokinetics of PEG liposome encapsulated doxorubicin are characterised by an extremely long circulating half-life, slow plasma clearance and a reduced volume of distribution compared with conventional liposomal doxorubicin or free doxorubicin. The long circulation and ability of pegylated liposomes to extravasate through 'leaky' tumour vasculature results in localisation of doxorubicin in tumour tissue. In a number of animal and human tumours, including breast, prostate, pancreatic and ovarian xenografts, pegylated liposomal doxorubicin produced higher intratumoural drug concentrations and better therapeutic responses than equivalent doses of conventional (nonpegylated)-liposome encapsulated doxorubicin or free doxorubicin. Low peak plasma concentrations of free doxorubicin after administration of pegylated liposomal doxorubicin and the reduced tendency of the liposomal drug to accumulate in myocardium suggest that a reduction in cardiac toxicity compared with free doxorubicin may be observed. Thus, the rationale for the use of pegylated liposomal doxorubicin in solid tumours may be summarised as follows: change in the toxicity profile with a decrease in acute adverse effects (such as nausea and vomiting) and reduced incidence of alopecia, greater activity in highly angiogenic tumours (such as Kaposi's sarcoma) and effective treatment of tumours moderately sensitive to doxorubicin (such as breast and ovarian carcinomas), with the possibility of increased tumour response because of enhanced drug accumulation. In addition, although no comparative study yet exists, there is a suggestion from early human studies with pegylated liposomal doxorubicin that cardiotoxicity may be reduced compared with the free drug. PMID- 9361958 TI - Clinical efficacy and prospects for use of pegylated liposomal doxorubicin in the treatment of ovarian and breast cancers. AB - There is an urgent need for more active and better tolerated chemotherapy regimens for the treatment of advanced breast and ovarian cancers. Current therapeutic strategies in these malignancies include the use of moderately effective initial regimens that are usually accepted by patients. Tolerability considerations are especially important in the development of palliative regimens: retreatment for persistent or hormone-resistant disease must include quality-of-life analyses. Pegylated liposomal doxorubicin (PLD) has demonstrated a better therapeutic index than free doxorubicin in murine solid tumours and human tumour xenografts in nude mice. In early clinical studies in patients with refractory ovarian cancer, PLD has produced high response rates (26%) and gratifyingly long response durations (8 to 21 + months after onset of therapy). Less mature data also suggest that PLD is active against breast cancer. Information from these same clinical studies confirms the marked reduction in several toxicities associated with free doxorubicin, including nausea and vomiting, myelosuppression and cardiotoxicity. Alopecia is also markedly diminished. On the other hand, mucosal and skin toxicities appear to be more common with PLD. PLD therefore offers the prospect of retaining activity, together with attenuated acute toxicity. In addition to facilitating the development of palliative regimens with better tolerability, the drug may lend itself to effective integration of chemotherapy with loco-regional therapies; utilisation in 'maintenance' regimens that are associated with an acceptable quality of life for the patient, and the avoidance of long term toxicities associated with treatment. Moreover, additional study of PLD in combination with other drugs and modalities may extend the use of the drug beyond palliation to the development of combination regimens with other drugs at conventional doses, and high doses with G-CSF support. PMID- 9361960 TI - Innate natural antibodies. Primary roles indicated by specific epitopes. AB - Two members of a unique class of natural antibodies have been identified in all of a large cohort of sera from clinically normal humans of broad age distribution. By means of a series of 10-12 mer peptides the epitope for each of those antibodies was characterized with regard to amino acid identity and conformation. Similar epitope specificity was revealed for the IgM isotopes of cord blood and early post natal sera and for IgM and IgG of adult sera, suggesting that the class of natural antibodies represented by the two identified in this study includes those genomically coded for at their effector level of maturation in the B cells of the neonate. Assay of series of specimens from each of four clinically normal adults revealed that those two natural antibodies are present at relatively constant titer, unique to each individual, over four to five and a half year periods. Those observations imply that the primary function of that class of natural antibodies may be related to maintenance of homeostasis and the molecular identity of each of the two epitopes suggests a role, for each, as monitor or control in intracellular traffic. The previous identification of those epitopes in a conserved protein of HIV also provides support for the proposition that a secondary function of natural antibodies, arising from fortuitous coincidence of the identity of the epitopes, may be that of early defense against infectious invaders. PMID- 9361959 TI - Safety aspects of pegylated liposomal doxorubicin in patients with cancer. AB - Encapsulation in polyethylene glycol-coated (pegylated; Stealth) liposomes alters the pharmacokinetic characteristics, and hence the safety and tolerability profile, of doxorubicin. Pegylated liposomal doxorubicin administered as a single agent is generally well tolerated. Grade III/IV leucopenia, stomatitis and palmar plantar erythrodysaesthesia affected 16, 6 and 18% of solid tumour patients, respectively. Other adverse effects included nausea and vomiting and alopecia. Acute hypersensitivity infusion reactions have been reported in up to 9% of patients in some studies. Recently published data from a phase II trial in patients with refractory ovarian cancer showed no alopecia or cardiotoxicity and little nausea and vomiting after pegylated liposomal doxorubicin. Unlike free doxorubicin, pegylated liposomal doxorubicin is not a vesicant. Preliminary data, not yet confirmed in comparative studies, suggest that the pegylated liposomal formulation may be less cardiotoxic than free doxorubicin. Mucositis, however, appears to be increased. Studies to determine optimal dosing schedules and safety of pegylated liposomal doxorubicin in combination with other agents are ongoing. PMID- 9361961 TI - EcoRI restriction fragment-length polymorphism of the human immunoglobulin variable lambda 8 (IGLV8) subgroup reveals a gene family. AB - The human immunoglobulin lambda locus (IGL) maps on chromosome 22q11.1-q11.2 and directs the synthesis of lambda-type Ig light chains. This locus is formed by three gene clusters (VA, VB and VC) that encompass the variable coding genes and the J-C cluster plus the joining segments and the constant genes. Recently the variable lambda gene clusters were mapped by the contig methodology which located all the known functional v-lambda genes and pseudogenes. The 30 functional v lambda genes described so far were subgrouped into ten families (V lambda I to V lambda X), but RFLP studies have estimated that the germline repertoire contains about 70 genes. Based on sequence comparisons, we defined specific oligonucleotide primers for the unique IGLV8S1 gene described. The cloned 244 bp product obtained from genomic DNA with these primers was sequenced and used as probe in Southern hybridization EcoRI RFLP analysis of Brazilian people. We detected the IGLV8S1 gene in a 3.7 kb EcoRI restriction fragment present in all the individuals analyzed, in agreement with the physical map of the IGL locus. Moreover, we detected an 8.0 kb EcoRI monomorphic fragment and a 6.0 kb EcoRI polymorphic fragment. These data suggest that the IGLV8 subgroup is a gene family. PMID- 9361962 TI - Dendritic cells generated from human blood in granulocyte macrophage-colony stimulating factor and interleukin-7. AB - Dendritic cells (DC), with potentially important clinical applications, have been generated from human peripheral blood monocytes in the presence of GM-CSF and IL 4 (G4 DC). In the present report we show that DC with a novel phenotype can be generated from blood adherent mononuclear cells in the presence of GM-CSF and IL 7 (G7 DC). Adherent cells from PBMC, cultured in GM-CSF (600 U/ml) and IL-7 (6 U/ml), were transformed over 7 days into cells with DC morphology, at a yield of 1.2-1.6 x 10(6) per 10(7) PBMC. G7 DC not only expressed class I and class II MHC, CD1a, CD11c, CD23, CD40, CD54, CD58, CD80, CD86 and CD95, like G4 DC, but also CD21, which is the complement receptor type 2, a ligand for CD23 and a receptor for EBV and IFN-alpha. G7 DC were at least one log more effective in the autologous MLR and at least two logs more effective in the allogeneic MLR, than PBMC. They elicited proliferative responses of CD4 T cells to tetanus toxoid and CD8 T cells to an EBV peptide, and stronger T-cell cytotoxicity to EBV peptide than G4 DC. Expression of CD21 by G7 DC suggests that IL-7 delivers a distinct signal to DC precursors and that G7 DC may be functionally distinct. PMID- 9361963 TI - Differential binding to frequent HLA-A alleles of p21 RAS derived peptides bearing oncogenic substitutions at position 12 or 13. AB - RAS oncogenic proteins are frequently found mutated in human cancers, where they are known to be implicated in the tumoral process. Mutations occur preferentially at positions 12, 13 or 61. Identification of potential T cell epitopes is the first step to determine it RAS mutated proteins can generate tumor specific antigens which could be further used as targets for cancer immunotherapy protocols. We have investigated the capacity of synthetic wild-type and mutant RAS derived peptides encompassing positions 12 and 13 to bind to three frequent HLA-A alleles: HLA-A*0201, HLA-A*0301 and HLA-A*1101. Binding was evaluated by two methods using TAP-defective cell lines: a cytometric assay based on HLA molecules stabilization at the cell surface, and an assembly assay detecting interactions between solubilized HLA molecules and peptides. Positive HLA binding was observed for two sets of synthetic peptides, one specific for HLA-A*0201 allele (RAS 5-14), and the other one specific for HLA-A*0301 and HLA-A*1101 alleles (RAS 8-16). Interestingly, the different substitutions at positions 12 and 13 were not equivalent for HLA binding. These observations will be useful for the in vitro generation of restricted CD8+ T lymphocytes specific for mutated RAS proteins and recognizing tumoral cells expressing such RAS mutations. PMID- 9361964 TI - Cytotoxic T lymphocyte recognition of HLA-G in mice. AB - Several features of HLA-G's sequence and expression pattern distinguish HLA-G from its classical counterparts. These features, including HLA-G's limited polymorphism and its expression at the maternal-fetal interface, have been used as a basis for suggesting a distinct functional role for this nonclassical class I HLA molecule. On the other hand, published data do demonstrate that HLA-G has much in common with its classical counterparts. It associates with beta 2 microglobulin and cytosolic peptides, it binds to CD8, and its presence can inhibit NK-cell-mediated lysis of HLA-G-bearing target cells. To develop a model in which HLA-G's function could be more thoroughly studied, we produced several HLA-G-expressing transgenic mouse strains. We report here the results of skin graft experiments which show that nontransgenic mice reject HLA-G-expressing transgenic murine skin as foreign and that this rejection is associated with the presence in the recipient of lymphocytes capable of specifically lysing HLA-G expressing cells. In addition, experiments are described which demonstrate that HLA-G transgenic mice recognize HLA-G as a "self" molecule. Together the reported data demonstrate that HLA-G is capable of stimulating an HLA-G-restricted CTL response, that HLA-G molecules can serve as target molecules in lytic interactions with CTLs, and that HLA-G is involved in education of the lymphocytic repertoire of HLA-G transgenic mice. PMID- 9361965 TI - Renal allograft infiltrating lymphocytes: frequency of tissue specific lymphocytes. AB - Acute rejection, mediated by T lymphocytes recognizing donor MHC class I and II, is a major factor influencing renal transplant survival. To define the specificity of these effector cells we examined cytolytic activity of graft infiltrating T lymphocytes (GIL) from renal biopsies of individuals undergoing acute cellular rejection. The majority of these cells recognized MHC class I on both donor kidney epithelial cells (KCL) and B-lymphoblastoid cells (LCL) suggesting these T cells recognized peptides from various tissues. However, cold target inhibition experiments demonstrated a significant proportion of GIL T cells were tissue specific. We reported previously that kidney specific CTL can be isolated from biopsies of kidney allografts undergoing acute cellular rejection. Here we extend that observation showing we were able to isolate tissue specific CTL from two additional biopsies. Greater than 10% of the clones isolated (4 of 36 and 5 of 37) from these biopsies were CTL recognizing donor KCL but not LCL targets suggesting that peptides, recognized in the context of donor MHC, were tissue specific. Repeated isolation of significant numbers of tissue specific CTL suggests these T cells play a role in allograft rejection and may be important effector cells mediating rejection in HLA matched transplants. PMID- 9361966 TI - Pretransplant exposure to donor HLA-DR antigen in random transfusion units and the development of donor antigen-specific hyporeactivity. AB - Our previous studies have shown that the in vitro assay of donor antigen-specific hyporeactivity is a useful marker for identifying solid organ transplant recipients (kidney, lung and heart) at low risk for immunologic complications (i.e., late acute rejection episodes and chronic rejection). Donor antigen specific hyporeactivity is defined as a significantly decreased post- vs. pretransplant proliferative response to donor antigens while response to third party controls remains unchanged. We analyzed whether exposure to the same HLA-DR antigen pretransplant via random blood transfusion and posttransplant via the transplanted organ influenced the development of hyporeactivity. Thirty previously nontransfused recipients, each receiving two 150 ml pretransplant random blood transfusions, were assessed for hyporeactivity at 1 year posttransplant. Of the 12 recipients with pretransplant exposure to kidney HLA-DR via transfusions, 6 (50%) developed hyporesponsiveness; in contrast, of the 18 recipients who were not preexposed, only 3 (15%) exhibited this form of immunomodulation. Of interest, 2 of the 3 hyporesponsive recipients who were not preexposed, received units containing HLA-DR antigens previously shown to share crossreactive epitopes with the kidney HLA-DR. In conclusion, these results suggest a increased incidence in the development of hyporeactivity in patients receiving pretransplant transfusions which share an HLA-DR antigen with the transplanted kidney. PMID- 9361967 TI - Influence of HLA alleles on the rate of progression of vertically transmitted HIV infection in children: association of several HLA-DR13 alleles with long-term survivorship and the potential association of HLA-A*2301 with rapid progression to AIDS. Long-Term Survivor Study. AB - The influence of host immunogenetics on the outcome of vertically transmitted HIV infection in children was examined in a multicenter cross sectional study of long term survivors and rapid progressors. Sequence-based typing was performed for the DRB1, DQB1 and HLA-A loci. 36.7% of 30 children surviving more than 8 years had one or more of the HLA-DR13 alleles, versus none of 14 rapidly progressing children who died within 2 years of age, p = 0.009, Haldane RR = 17.1. The alleles variably associated with this beneficial response to HIV were: DRB1*1301, DRB1*1302, DRB1*1303 and DRB1*1310, suggesting that the DR13 effect acted as a dominant trait. An additional 6 children were typed only by the SSOP method resulting in 44.4% of 36 long term surviving children with a DR13 allele and none of 14 rapid progressors, p = 0.002, Haldane RR = 23.3. No single DQB1 allele accounted for the HLA-DR13 allele association. In contrast, the presence of HLA A*2301 was associated with rapid progression to AIDS, 4% of long term survivors vs. 57.1% of 7 rapid progressors, p = 0.0006, RR = 0.031. Although the sample size is small, the marked differences in allele frequency along with differences between the peptide binding pockets of the HLA-A9 group of alleles including HLA A*2301 and the remainder of the HLA-A alleles suggest a structural basis for the dominant disadvantageous immune response to HIV conferred by A*2301. PMID- 9361968 TI - Alloresponses to HLA-DP detected in the primary MLR: correlation with a single amino acid difference. AB - The one-way mixed lymphocyte reaction (MLR-1) response was measured in both directions in 50 HLA-A, B, DR and DQ identical pairs and the role of DP studied in MLR stimulation. DR, DQ and DP typing was performed at the allele level by the polymerase chain reaction-sequence specific oligotyping (PCR-SSO) technique. The group consisted of 19 potential bone marrow transplant recipients and 34 matched unrelated donors. When more than one matched donor was available for a patient, donor/donor MLR-1 was also studied. DP identity was observed in 3 out of 50 pairs (6%), however due to homozygosity no incompatibility was present in the stimulating cells in 21 out of 100 cases (21%). There was a significant difference in the range of relative responses (RR) between zero DPB1 mismatches and one (p = 0.002) and two (p = 0.02) DPB1 mismatches: 52.4% of cases in the zero DPB1 mismatch group had RR < 1.0% compared with 31.6% and 27.3% in the one and two DPB1 mismatches. Stimulation by DPB1*0201 and 0301 gave the highest RR (12.9 +/- 22.5 and 17.5 +/- 17.0, respectively) while stimulation with DPB1*0401 and 0402 resulted in low levels of T cell response (1.3 +/- 8.2 and 0.6 +/- 11.5, respectively). When the responses were restricted to DPB1*0401 homozygotes to standardise for responder type similar results were obtained (DPB1*0201 v DPB1*0402 p = 0.008). The protein products of the DPB1*0201 and 0402 alleles differ by a single amino acid at position 69 (DPB1*0402--Lysine, DPB1*0201- glutamic acid). A further analysis was performed therefore scoring responders and stimulators as glutamic acid positive (E+) or negative (E-). There was a highly significant increase in the response to E+ stimulators compared with E- stimulators (p = 0.004). There was also a significant difference in the distribution of relative responses between the E+ stimulator group and the subgroups of E- responders/E- stimulators (p = 0.012) and E+ responders/E- stimulators (p = 0.009). However the amino acid difference at position 69 does not explain all responses due to DP in the MLR-1 as evidenced by the strong responses observed in cases where DPB1*0301 (lysine pos.) was the only difference on the stimulator cells. The results indicate that not all DP incompatibilities elicit a measurable T cell MLR response, but where a response does occur residue 69 in the first domain of DP appears to be pivotal. These results may have implications with respect to GVHD in bone marrow transplantation. PMID- 9361969 TI - HLA associations in insulin-dependent diabetes mellitus: no independent association to particular DP genes. AB - Genes in the HLA complex are associated with susceptibility to develop insulin dependent diabetes mellitus (IDDM). Several studies, from different populations, have demonstrated strong associations between particular DR and DQ alleles and disease susceptibility or protection. Whether also particular DP alleles may independently contribute is more controversial. Some studies have found a greater frequency of DPB1*0301 among IDDM patients compared to controls, apparently independently of linkage disequilibrium with high risk DR and DQ alleles. To address this question in an ethnically homogeneous population (Norwegian), we have DPA1 and DPB1 genotyped 237 IDDM patients and 287 DRB1-DQA1-DQB1 matched controls, carrying high risk DR3/4 or DR4/4 genotypes. We were unable to detect any significant independent associations between DP alleles and IDDM susceptibility or protection in this population. Thus, our results do not support previous reports on an independent association between some DP alleles and susceptibility to develop IDDM. PMID- 9361970 TI - Soluble HLA class I antigens in patients with type I diabetes and their family members. AB - Our objective was to study a possible contribution of MHC genes to S-HLA-I secretion in patients with Type I diabetes. Quantitatively, we used a highly sensitive enzyme-linked immunoassay to measure S-HLA-I in the serum of a total of 39 patients with Type I diabetes, as well as 36 kinships of 12 diabetic patients and 82 normal individuals with known HLA-phenotypes. S-HLA-I levels were abnormally elevated in patients or their non-diabetic relatives compared to normal controls (p < 0.0009). No complete HLA-haplotype had been identified to be correlated with high or low S-HLA-I secretion. Only the HLA-A23 or A24 (splits of HLA-A9) positive individuals sera were found to contain high S-HLA-I concentrations in all populations studied. The difference in S-HLA-I levels of HLA-A24 patients (n = 4) or their HLA-A24 positive non-diabetic relatives (n = 10) to the group of HLA-A24 normal controls (n = 15) was statistically highly significant (p < 0.0005 and p < 0.0009, respectively). The results suggests that HLA-A24 may confer additional independent risk for the disease expression in male children but not in female siblings. Nevertheless, the data implies that the patients or their non-diabetic relatives carrying the HLA-A24 have increased risk of developing ICA associated with high S-HLA-I levels compared to HLA-A24 negative probands or their kinships with low levels of S-HLA-I. This effect occurred irrespective to other diabetes related HLA-DR alleles. In summary, the results show a pronounced genetic heterogeneity of Type I diabetes with MHC control of the expression of S-HLA-I and possible involvement of hormonal factors that might potentiate a specific synthesis of S-HLA-I. The findings have implications for identifying individuals with a possible risk for developing the disease. PMID- 9361972 TI - Computed tomographic and magnetic resonance imaging of the pediatric airway. PMID- 9361971 TI - New alleles of the HLA-B15 family. AB - In a previous study of B locus alleles by sequence-specific oligonucleotide probe (SSOP) hybridization, we observed 18 novel patterns in a panel of 360 individuals. Four of these novel patterns were caused by alleles of the human leukocyte antigen (HLA)-B15 group, and three were available for this study. These alleles were found in Oriental, Latin American, African American, and Caucasian individuals. In addition, we analyzed a Caucasian subject who was found by serology to have an unusual B15 specificity. We sequenced these four samples by performing amplification from genomic DNA using polymerase chain reaction primers designed to obtain HLA class I products that included exon 2 and exon 3 as well as the intervening intron. The amplified segments were cloned and identified by colony hybridization with nonradioactive SSOP. Nucleotide sequences were obtained using an automated DNA sequencer. The allele B*1530 differs from B*1501 by a substitution of Asp for Asn in position 114 and Ser for Tyr in codon 116. The new allele B*1531 differs from B*1502 at amino acids 94, 95, and 152. The variant B*1524 was found to have N-77, I-80, A-81, L-82, R-83. A similar motif exists in B locus alleles that have the supertypic specificity Bw4 and in B*1513, B*1516, B*1517, and B*1523; it is likely to have been generated by gene conversion. Finally, the novel allele B*1527 is similar to B*1501 except for the presence of Phe instead of Tyr at position 99. Because this change exists also in B*1506, it is possible that B*1506 was derived from B*1501 through B*1527. It is of interest that a similar substitution (Cys for Tyr at position 99) distinguishes A*0201 from A*0207 and is known to determine an epitope recognized by T cells. Thus, B*1527 may also carry a change that is functionally relevant in cell-mediated immunity. PMID- 9361973 TI - Complications from securing the difficult airway. AB - Attempts to secure the difficult airway, especially the pediatric airway, can have nightmarish consequences if not successful and may be followed by complications even when successful. Some complications are common and some are rare. To minimize the risk of any complications, the clinician needs to be prepared mentally and technically to manage the difficult airway, must prepare the equipment, and must educate the patient/parents regarding possible difficulties with airway management. PMID- 9361974 TI - Advanced airway management by prehospital personnel: dangerous or necessary? PMID- 9361975 TI - Inspiratory muscle incoordination and upper airway obstruction during inhalation anesthesia. PMID- 9361976 TI - The laryngeal mask airway. PMID- 9361977 TI - Mechanisms and treatment of laryngospasm. PMID- 9361978 TI - Pulmonary edema after airway obstruction. PMID- 9361979 TI - Sinusitis and lower airway reactivity. PMID- 9361980 TI - Sevoflurane in pediatric ear, nose, and throat procedures. PMID- 9361981 TI - Airway management for CO2 laser surgery on the larynx: Venturi jet ventilation and alternatives. AB - Supralaryngeal Venturi jet ventilation provides superb surgical visualization and access to the larynx, including the anterior and posterior commissure. When VJV is delivered through a metal cannula and laryngoscope or all-metal endotracheal tube or bronchoscope, there is no inorganic combustible material in the surgical field, making supralaryngeal VJV a safe as well as effective technique for CO2 laser surgery on the airway. PMID- 9361982 TI - Pediatric laser bronchoscopy. AB - Endoscopic laser surgery can be performed in the airway safely and effectively when a team approach is used. Our team of anesthesia and surgical personnel prefers to treat lesions involving the supraglottic, glottic, or immediately subglottic trachea with a CO2 laser through the laryngoscope, using Venturi ventilation and intravenous sedation and pharmacological paralysis. For distal airway lesions, as far as the mainstem bronchi, our preference is to use manual positive pressure ventilation through a rigid bronchoscope with a flexible KTP or argon fiberoptic laser. Oxygen concentrations should be kept below 50% if possible and one should avoid material that can ignite. For lesions distal to the mainstem bronchi, we prefer to use a flexible bronchoscope through a standard endotracheal tube. PMID- 9361983 TI - Role of subglottic injury, gastric juice, and peptide growth factors in a porcine model. PMID- 9361985 TI - Decreasing morbidity following laryngotracheal reconstruction in children. PMID- 9361984 TI - Postoperative management of laryngotracheal reconstruction. PMID- 9361986 TI - Airway complications in patients with infection caused by HIV. AB - Numerous problems may be identified in the airways of patients with HIV infection. In many cases, these airway conditions represent exaggerations of infections seen in the immunocompetent host. However, in other instances, they represent manifestations of unique problems, infectious and/or neoplastic, that are a consequence of the profound immunosuppression seen in the patient with infection due to HIV. PMID- 9361988 TI - Surgical research and education and the three Rs. PMID- 9361987 TI - Military surgery and surgical advances. PMID- 9361989 TI - Interstitial lymphoscintigraphy for lymphatic mapping in surgical practice and research. AB - Lymphoscintigraphy is a nuclear medicine technique that gives morphologic and functional information about the lymphatic system. The size of radiopharmaceutical used is a critical factor for it to have acceptable characteristics of uptake by the lymphatics and migration to lymph nodes. A small particle (10-100 nm) with opsonins or a unique surface is required for uptake by lymph-node macrophages. It can be prepared for application with a simple filtering process producing a predictable size distribution and number of particles for the scan. The radiation dose is safe for the patient and staff. Technetium-99m sulfur colloid is readily available and approved for use. The injection can be performed by anyone with certification in handling radiopharmaceuticals. Imaging is done with standard gamma cameras available in any nuclear medicine department. The addition of the hand-held gamma probe adds a new dimension to application of the technique of lymphatic mapping and identification of areas that retain radiopharmaceuticals. Its use is simple and reproducible. The application of lymphoscintigraphy and gamma-probe localization techniques in clinical medicine is best exemplified with the now commonly used sentinel node approach to staging and treating intermediate-thickness malignant melanoma. A number of other malignant diseases such as breast cancer may have their treatments altered with these techniques as well. As a research and diagnostic tool, the creative application of interstitial lymphoscintigraphy can give important qualitative information regarding the morphology and physiology of the lymphatic system. The development of these techniques for surgical research and practice is reviewed. PMID- 9361990 TI - In vivo strain measurements collected using calcium phosphate ceramic-bonded strain gauges. AB - Identification of the strains and the strain changes caused by implants is critical to the understanding of bone remodeling and can identify design changes needed to prevent bone loss near orthopedic implants. Calcium phosphate ceramic (CPC) coated strain gauges have been developed to allow long-term in vivo strain measurements. Previously used cyanoacrylate-bonded gauges have uncharacterizable sensing accuracy because the adhesive is resorbed from the instant it is placed in vivo. In this study CPC-coated strain gauges were used to measure physiologically "normal" bone strains collected from the proximal femora of dogs at a series of gait speeds and the postmortem sensing accuracy of the gauges was evaluated. Three male dogs were surgically implanted with up to six wired CPC coated strain gauges placed around the circumference of their proximal femora. The dogs were trained to run on a treadmill, and in vivo strain measurements were collected following a 12-week period. The animals were tetracyline labeled and then euthanized and their femora explanted. Gauges were attached with cyanoacrylate to the intact contralateral control femora in the same position as the CPC-coated gauges on the test femora. Both femora were tested in cantilever bending to assess the functionality of the gauges and quality of the CPC-bone bond. After testing, all bones were embedded, sectioned, and ground. Sections from each femur were stained with mineralized bone stain and examined with transmitted and ultraviolet light to assess bone formation. Additional sections were examined with backscattered electron microscopy to confirm bone bonding to coatings. Wired gauges attached with the CPC coatings measured strain patterns during gait at several treadmill speeds. Patterns were similar and peak strains the same over a 2-week period. Mechanical testing showed bonding of CPC-coated gauges, and histologic examination showed intimate contact between gauge coatings and bone surfaces. Further development of CPC-bonded strain gauges is expected to result in a measurement system that provides ease of placement, and consistent longer term bone strain measurements with characterizable accuracy. PMID- 9361991 TI - Electro-ureterogram: canine study of the electromechanical activity of the ureter. AB - The purpose of this investigation was to study the electromechanical activity of the ureter aiming at characterizing an "electro-ureterogram" that might be of diagnostic significance. Eighteen mongrel dogs were used in this study. Under anesthesia the ureter was exposed and three electrodes (monopolar, silver-silver chloride, 0.8 mm in diameter) were sutured to the ureteric adventitia, 2-3 cm apart. The intraureteric pressure was measured by a scalp vein needle inserted into the ureteric lumen and connected to a pressure transducer. The ureteric electric activity and pressure were recorded 30 min daily for 15 days. The electric activity was also registered after having performed ureteric myotomy in 12 out of 18 dogs. Monophasic negatively deflected slow waves or pacesetter potentials were recorded. Their frequency, amplitude, and velocity were identical in the three electrodes and reproducible. The pacesetter potentials were followed by fast activity spikes or action potentials that occurred randomly and were inconsistent. The action potentials were associated with ureteric pressure increase. After ureteric myotomy, both the pacesetter potentials and action potentials were recorded proximally to the myotomy but not distally to it, indicating a caudal spread of the waves. In conclusion, a normal electro ureterogram could be characterized. It might show changes in various pathologic conditions of the ureter and could thus be included as an investigative tool in the diagnosis of ureteric diseases. PMID- 9361992 TI - Cerebral trauma-induced changes in corpus striatal dopamine receptor subtypes. AB - A device designed specifically for mild to severe concussions was used to produce quantitative experimental blunt brain injury in male Wistar rats. We have examined the effects of varying magnitudes of cerebral trauma on the maximal binding capacity (Bmax) of D1 and D2 dopamine (DA) receptors. The Bmax for each receptor subtype was obtained from Scatchard analyses of [3H]-SCH 23390 and [3H]Spiperone binding to striatal membrane. Anesthetized rats were injured--one, two, or three times--once every 24 h, with either a 68- or 268-g rubber-headed reflex hammer accelerated from a predetermined distance. Uninjured nonanesthetized (NA) and anesthetized (A) rats served as controls. No significant difference in receptor density was observed between NA and A rats for each receptor subtype. Immediately (0 h) following injury from the 68-g hammer weight, the density of D1 receptors decreased (50%), then increased (30%) above control levels by 24 h. The same pattern was observed with the 268-g hammer weight. Analysis of variance (ANOVA) showed that there was no overall effect of number of injuries or treatment on the density of D1 and D2 receptor subtypes. However, there was an interaction of both variables on the D1, but not D2, receptor subtype. Partial ANOVA for receptor densities after rats were injured either one, two, or three times showed that receptor density was altered only after the rats were injured one time. These results suggest that striatal DA D1 receptors are downregulated and then upregulated following isolated injury to the cerebral cortex. PMID- 9361993 TI - Glucose suppresses the activity of rat oxyntic histidine decarboxylase without affecting gastrin levels. AB - Glucose suppressed the activity of oxyntic mucosal histidine decarboxylase within 2 h when given either intragastrically or intraperitoneally to rats fasted for 24 h. Serum levels of gastrin, secretin, glucagon, and somatostatin and oxyntic mucosal levels of gastrin, histamine, and somatostatin showed no significant changes after glucose. Glucose suppressed the aspirin-induced histidine decarboxylase activity without changing serum gastrin. It also suppressed the pentagastrin-induced histidine decarboxylase activity. Neither fructose nor mannitol had such an effect. These results suggest that glucose acts directly on the enterochromaffin-like cells in rat oxyntic mucosa to suppress histidine decarboxylase activation. PMID- 9361994 TI - An adult canine model of progressive left ventricular pressure overload. AB - This article details the development of a model of progressive left ventricular pressure overload (LVPO) in the adult dog. LVPO was induced by banding the proximal ascending aorta in 69 adult conditioned dogs. The base of the aorta was exposed through a right thoracotomy. A tunnel was created by blunt dissection between the aorta and pulmonary arteries. An aortic band was constructed by passing umbilical tapes through the lumen of gortex tubing. This band was placed through the tunnel, then tied around a balloon dilatation catheter. The distal end of the balloon catheter was closed with an injection cap and positioned in a subcutaneous pocket. Aortic stenosis was induced by filling the balloon catheter with saline. A predetermined amount of LVPO was created by adjusting the amount of aortic stenosis. At 2, 4, and 6 weeks after aortic banding the LVPO was increased by transcutaneous injection of saline into the balloon catheter. At 8 weeks the dogs were evaluated for sufficiently decreased cardiac contractility and used acutely in one of several studies. The article also discusses perioperative management, postoperative care, and complications that were encountered during the development of the model. Postoperative pain was managed by the combined use of preemptive and postoperative opioids, local nerve blocks, and nonsteroidal anti-inflammatory drugs. Notable intraoperative complications included atrial and ventricular arrhythmias and pulmonary artery laceration during the banding procedure. The most significant postoperative complications were aortic ruptures and congestive heart failure. The success rate of this model has increased from 20% (year 1) to 65% (year 3). This success has been attributed to improvements in band design, surgical technique, and postoperative management. PMID- 9361995 TI - Rabbit model for the study of aortic graft infection. AB - Despite improvements in surgical technique and antimicrobial therapy, prosthetic aortic graft infections remain a challenging clinical problem. Diagnosis is difficult, and treatment results are less than optimal. An animal model is needed that will allow critical investigation of novel approaches in the therapy of aortic graft infections. Three-millimeter internal diameter polytetrafluoroethylene vascular prostheses were anastomosed as aortic interposition grafts in 25 rabbits. Increasing concentrations of Staphylococcus aureus (no bacteria to 1 x 10(8)) were applied topically to inserted grafts to initiate infection. There were 15 long-term survivors. Surviving rabbits were sacrificed at 2 weeks postoperatively to evaluate the development of aortic graft infection. Of the 15 survivors, 6 developed graft infection. All infected prosthetic aortas were innoculated with 1 x 10(4) or higher concentrations of S. aureus. A cost-effective, reliable model has been developed suitable for the study of prosthetic aortic infection. PMID- 9361996 TI - Application of robotic and prerobotic devices in laparoscopic surgery. PMID- 9361997 TI - Expression of inducible nitric oxide synthase in human lungs. AB - The aim of this study was to investigate the expression of inducible nitric oxide synthase (iNOS) in lungs of patients with or without adult respiratory distress syndrome (ARDS). We compared the expression of iNOS by immunohistochemical analysis and polymerase chain reaction in the human lungs collected during open lung biopsy or at autopsy. The expression of iNOS mRNA was present in all lung samples; however, only 3 out of 11 lung samples showed weak staining for iNOS. Although the involvement of nitric oxide in animal models of ARDS is reported, production of nitric oxide in human lungs is still controversial. The data presented here suggest that human lungs express iNOS mRNA but that the production of iNOS protein may be tightly regulated and is expressed in pulmonary inflammation. PMID- 9361998 TI - Intraventricular hemorrhage and long-term outcome in the premature infant. AB - Intraventricular hemorrhage (IVH) is a common, serious problem among premature infants. With advances in neonatal care, improved survival rates of small premature infants and improved diagnostic capabilities, IVH is seen with increased frequency in the high-risk nursery. Studies indicate 15-20% of premature infants (birth weight less than 1,500 gms), have been noted to have IVH Many of these neonates survive beyond infancy and may subsequently be seen in pediatric neurosurgery and neurology clinics with long-term problems such as hydrocephalus, cerebral palsy, mental retardation and seizures. Although long term sequelae are not always present, it is beneficial for the neuroscience nurse to be able to understand the mechanisms of brain injury with IVH in order to anticipate long-term problems and provide comprehensive follow-up care for infants and children with this diagnosis. PMID- 9361999 TI - The lived experience of relapsing multiple sclerosis: a phenomenological study. AB - Multiple sclerosis (MS) is a demyelinating disease of the central nervous system that is well known but poorly understood by the medical and nursing community as well as the general public. The myriad neurological symptoms result from an autoimmune attack on the insulating myelin of the nerves which cause a disruption of nerve impulses in the brain and spinal cord. MS most often affects young adults and may be broadly categorized as either a relapsing or a chronic progressive disease course. Until recently, research has focused on the progressive form of MS though it accounts for less than half of the cases. People who are diagnosed with relapsing MS are cared for in the same way as those with the debilitating progressive form. Relapsing MS affects individuals periodically with exacerbations from which they often recover completely, whereas chronic MS results in a progressive functional deterioration. People with relapsing MS are not given a realistic prediction of what to expect in their future nor are they left with any hope for normalcy in their lives. The purpose of this study was to provide a description of the lived experience of people who have relapsing MS. To answer the question, "What is the lived experience of people with relapsing multiple sclerosis?" this study was conducted using hermeneutic phenomenology. A sample of 10 patients with relapsing MS was interviewed over a seven month period. Interviews began with the question, "What is it like for you living with multiple sclerosis?" The interviews were tape recorded and transcribed verbatim. Data were analyzed using the Colaizzi method of hermeneutic phenomenology. Themes that emerged from the data were combined and abstracted into twelve dimensions that described the lived experience of people with relapsing MS. Participants' social networks served as either positive or negative influences in their adjustment process and led to conflicts for some. Coping with recurrent symptoms and social situations related to the MS was facilitated by maintaining control and a sense of hope. Most expressed a sense of relief with diagnosis because they had secretly feared their symptoms were a result of a fatal illness or psychological instability. Uncertainty surfaced as a major theme due to the unpredictability of relapsing MS. Participants also experienced fear and loss. Getting to know MS was an integral part of the experience often made difficult by concealment of facts. Participants experienced acts of revealing and concealing throughout their illness process and often attempted to conceal their illness from a society that did not understand. Nurses should be aware of the relapsing MS experience when providing care and teaching to patients and families with MS. The nurse should also reflect on the importance of maintaining hope and open communication. PMID- 9362000 TI - Postcomatose unawareness/vegetative state following severe brain injury: a content methodology. AB - Postcomatose unawareness/vegetative state (PCU/VS) is an altered state of consciousness that may follow coma. It is characterized by wakefulness without awareness of self or the environment. While most frequently associated with trauma, it is also associated with anoxia, vascular injury or encephalitis. In this article, the clinical phenomenon of PCU/VS is explored using the content methodology process (CMP) in order to explicate content for nursing practice. There are five steps in the process: literature review, identification of the characteristic features and patient behaviors associated with PCU/VS, description of the specific abilities that are affected, formulation of nursing assessment and intervention approaches, and evaluation of these approaches in clinical practice and research. In this article, there is an extensive review and analysis of the literature related to PCU/VS. Substantive nursing knowledge was developed using the CMP. It was determined that the Freeman Questionnaire and the Sensory Stimulation Assessment Measure are appropriate tools to assess the interpretative abilities of patients with PCU/VS during the acute care period. Sensory regulation techniques that are appropriate for use during patient care to promote the recovery of cognitive abilities were identified. Both the recommended tools and the intervention approaches require further validation in empirical research. PMID- 9362001 TI - Hyperdynamic therapy: the nurse's role in the treatment of cerebral vasospasm. AB - The onset of subtle diffuse ischemic neurological deficits often associated with cerebral vasospasm is a major cause of morbidity and mortality following aneurysmal subarachnoid hemorrhage. The exact etiology of cerebral vasospasm is unclear. Increasing intravascular volume, decreasing blood viscosity and inducing hypertension may help prevent or diminish neurological deficits from cerebral vasospasm by improving cerebral blood flow. An intensive multidisciplinary approach is necessary with the role of the neuroscience nurse being pivotal. An understanding of the subtle neurological changes suggestive of cerebral vasospasm and its effects leads to early recognition, and allows for rapid institution of therapy. PMID- 9362002 TI - Dysphagia: a screening tool for stroke patients. AB - Initiating safe oral nutrition and hydration immediately following stroke had become a critical concern for health care professionals at our facility. The Examine Ability to Swallow (EATS) dysphagia screening protocol, administered by nurses, was developed to solve this clinical dilemma. The dysphagia screening process for the acute stroke patient has successfully met the facilities' needs and more importantly has increased patients' satisfaction. No formal data were collected. This proactive approach is beneficial to the patient's physiological status as a means of preventing adverse complications; which impacts the recovery time frame for the patient. In addition it promotes the emotional well being of patients, and is economically prudent. This is an asset in today's healthcare environment. PMID- 9362003 TI - Pharmacologic management of epilepsy: an update. AB - A fifteen-year hiatus separated the availability of established AEDs and the new AEDs, after which the 1990s brought four new AEDs on the market. The new AEDs offer many alternatives that were unavailable before this decade for people with refractory epilepsy. Because AED clinical trials are usually based on efficacy in refractory patients, new drugs have an indication only for adjunctive therapy in people with poorly controlled seizures. In spite of their indication as adjunctive therapy, the new AEDs may eventually prove to be useful in monotherapy and even initial therapy of partial and secondarily generalized seizures. Although none of the new AEDs met all the criteria of an ideal AED, namely high oral bioavailability, rapid absorption, linear kinetics, negligible protein binding, long half life, renal excretion and low potential for drug interactions, they represent significant advances over the established AEDs. The only major barrier to broader use of the new AEDs appears to be cost. PMID- 9362004 TI - Neuroscience nursing research: challenges for the next decade. AB - Nurses are making a significant difference in health care today and research is the key to making our practice the best that it can be. Our goal is to facilitate that research and to promote excellence in the knowledge underlying clinical practice. We should be proud of the accomplishments so far, but challenges and opportunities exist for the future. Neuroscience nurses are at the forefront of some of the most exciting avenues for scientific discovery. NINR research, past, present, and future will contribute to these efforts. PMID- 9362009 TI - Call to molecular arms. PMID- 9362010 TI - Surface rendering of three-dimensional myocardial SPECT: clinical usefulness compared with bull's-eye and conventional tomograms. AB - BACKGROUND: A prospective study was conducted to evaluate the clinical usefulness of three-dimensional (3D) surface-shaded maps for routine practice of myocardial perfusion single-photon emission computed tomography (SPECT) by comparison with 2D slices and 2D bull's-eye qualitative analysis. METHODS AND RESULTS: Angiograms were performed on 201 consecutive patients, 155 with coronary artery disease (CAD) and 46 with no significant CAD. One-day 201TI stress/rest-reinjection protocol was performed in 110 patients, and 1-day 99mTc-sestamibi or tetrofosmin stress/rest protocol was performed in 91. The stress protocol was either exercise or dipyridamole (0.56 mg/kg) infusion. Three-dimensional surface maps were obtained by using a threshold for the transaxial data at 50%, 55%, 60%, 65%, and 70% of the maximum pixel value in the first 60 patients. Interpretation of 3D maps was based on the presence of a complete (transmural-looking) perfusion hole within the myocardial wall; doubtful patterns were considered pathologic or normal. Good diagnostic values were found for the 50% to 60% thresholds, but the 60% setting showed the best concordance with multislice and bull's-eye analysis; higher values drastically degraded the specificity. Considering doubtful patterns as normal clarified interpretation and led to a small loss in sensitivity but high gain in specificity. Applied to the whole population, the 3D maps using a 60% threshold provided similar diagnostic value to detect CAD as did conventional and bull's-eye analysis. Moreover, the 3D maps showed a trend toward higher specificity and a proportionally smaller decrease in sensitivity (sensitivity: 92.9%, 90.3%, 89.7%; specificity: 45.6%, 50.0%, 58.7% for tomograms, bull's-eye analysis, and 3D maps, respectively), especially for the detection of left anterior descending and right CAD. Multivessel disease was detected in an identical manner. Three-dimensional maps might improve detection of perfusion defects in the basal regions. However, 3D maps were found to be less sensitive than slices and particularly bull's-eye analysis for the reversibility of stress defects. CONCLUSIONS: Three-dimensional surface display of myocardial perfusion is a valuable independent tool for determining presence, extent, and location of CAD. It can convey useful first-look information to the referring physician, especially through a cine-rotational motion (as done in our practice through use of a floppy disk. PMID- 9362011 TI - Fast acquisition of myocardial SPECT images with Tc-99m sestamibi for the diagnosis of coronary artery disease. AB - BACKGROUND: Shortening the acquisition time for myocardial single-photon emission computed tomographic (SPECT) imaging increases patient comfort and laboratory throughput. The purpose of this study was to compare the diagnostic accuracy for coronary artery disease detection of myocardial SPECT images acquired in 5 to 10 minutes versus 25 minutes using Tc-99m methoxyisobutylisonitrile (Tc-99m sestamibi) and a single-head gamma camera. METHODS AND RESULTS: Forty-one subjects had a standard 1-day rest/stress Tc-99m sestamibi myocardial SPECT study. Two sets of rest and stress images were acquired on the same day for each subject. One set of images was acquired with a 5- to 10-minute fast acquisition protocol; the second set of images was acquired with a 25-minute standard protocol. The accuracies of the fast and standard protocols for identifying individuals with and without coronary artery disease were equivalent. Accuracy was 76% for the fast protocol and 73% for the standard protocol in individuals with at least one coronary stenosis > or = 70%. The accuracies of the two protocols for identifying individual coronary arteries with stenoses > or = 70% also were equivalent. Accuracy was 77% for the fast protocol and 74% for the standard protocol. CONCLUSIONS: SPECT myocardial images may be acquired in as little as 5 to 10 minutes using Tc-99m sestamibi and a 1-day rest/stress protocol. Accuracy is equivalent to that attained in studies with longer imaging times. PMID- 9362012 TI - Inotropic stress with arbutamine is superior to vasodilator stress with dipyridamole for the detection of reversible ischemia with Tc-99m sestamibi single-photon emission computed tomography. AB - BACKGROUND: There is a paucity of data comparing the relative merits of inotropic and vasodilator stress Tc-99m sestamibi single-photon emission computed tomography (SPECT) for the detection of coronary artery disease and reversible ischemia. METHODS AND RESULTS: Twenty-seven patients referred for diagnostic coronary arteriography underwent separate day dipyridamole and arbutamine Tc-99m sestamibi SPECT imaging with simultaneous two-dimensional echocardiography. The sensitivity of arbutamine and dipyridamole Tc-99m sestamibi for the detection of coronary artery disease was 100% (21 of 21) and 90% (19 of 21), respectively, with a specificity of 66% (4 of 6) for both. Coronary artery disease was detected in all six patients with single vessel disease by both stress modalities. The sensitivity for prediction of multivessel disease was 66% (10 of 15) for arbutamine and 46% (7 of 15) for dipyridamole stress. Arbutamine stress induced a greater extent and severity of perfusion abnormality at peak stress (peak perfusion score 25 +/- 6.2 and 21 +/- 5.9 for arbutamine and dipyridamole, respectively, p = 0.001) and reversible perfusion defects (difference between peak stress and rest scores 8.8 +/- 5.5 and 5.2 +/- 4.4 for arbutamine and dipyridamole, respectively, p = 0.001). Furthermore a significantly higher percentage of reversible defects induced by arbutamine stress was associated with wall thickening abnormality on simultaneous echocardiography, which is a more specific marker of myocardial ischemia (88% and 24% for arbutamine and dipyridamole, respectively, p = 0.002). CONCLUSION: Inotropic stress may be superior to vasodilators for the determination of the extent and severity of myocardial involvement and reversible ischemia by Tc-99m sestamibi SPECT. PMID- 9362013 TI - Analysis of cardiac arrhythmias during dobutamine pharmacologic stress testing in nuclear cardiology as related to the presence or absence of baseline arrhythmias. AB - BACKGROUND: Intravenous dobutamine is an acceptable pharmacologic stress agent for evaluation of myocardial ischemia, but it has the undesirable side effect of precipitating cardiac arrhythmias. All patients are susceptible to the arrhythmogenic potential of dobutamine. However, the presence of a baseline arrhythmia creates additional concern about proceeding with a pharmacologic dobutamine stress test. The purpose of this study was to evaluate cardiac arrhythmias during dobutamine stress as they relate to the presence or absence of baseline arrhythmias in patients undergoing radionuclide myocardial perfusion imaging. METHODS AND RESULTS: Data from 486 consecutive dobutamine stress tests in nuclear cardiology were reviewed retrospectively. Baseline and stress electrocardiographic monitoring and 12-lead electrocardiograms were used for classification of arrhythmias. For patients without baseline arrhythmias, the estimated probability of having nonsustained ventricular tachycardia with dobutamine stress was 4.0% (16 of 403), as compared with 15.7% (13 of 83) for patients with baseline arrhythmias (p < 0.001). Three of the 403 patients (0.7%) and 2 of the 83 patients (2.4%) had their study terminated because of ventricular tachycardia (p > 0.05). CONCLUSIONS: The probability of having nonsustained ventricular tachycardia with dobutamine stress testing was significantly greater in patients who had baseline arrhythmias than in those who had no arrhythmias at baseline. Although termination of the study because of ventricular tachycardia was not statistically significant between these two groups, patients with baseline cardiac arrhythmias should be considered at higher risk for the development of nonsustained ventricular tachycardia during dobutamine stress testing than patients who have no baseline arrhythmia. PMID- 9362014 TI - Relationship of scar and ischemia to the results of programmed electrophysiological stimulation in patients with coronary artery disease. AB - BACKGROUND: Although myocardial perfusion imaging (MPI) is widely used in patients with coronary artery disease, few data are available concerning the relationship between myocardial scar and ischemia and arrhythmic potential. PATIENTS AND METHODS: One hundred forty-four patients with chronic coronary artery disease who underwent electrophysiological studies (EPS) and MPI within 3 months constituted the study population. By history, 26% of the patients had sustained ventricular tachycardia (VT), 21% had cardiac arrest with ventricular fibrillation, and 53% had nonsustained VT. Eighty-five percent had previous myocardial infarction. Standard EPS protocol with up to three extra stimuli was used. Patients with a response of sustained monomorphic VT were defined as inducible. Quantitative MPI was used to define stress perfusion defect size and reversibility. The relations of ischemia (reversible defect) and scar (fixed defect) to inducibility on EPS were assessed by univariate analysis. Multivariate analysis was used to compare MPI results with known clinical predictors of inducibility. RESULTS: Fifty-two percent of the patients had inducible monomorphic sustained VT. MPI showed scar alone in 33%, scar with additional ischemia in 53%, ischemia alone in 8%, and no abnormality in 6%. No relation was found between the scintigraphic presence or size of ischemia and the likelihood of inducibility or to the type of arrhythmia history. In contrast, scar size was related to the result of EPS; inducible patients had significantly larger resting defect integrals (27 +/- 23 vs 14 +/- 15) than noninducible patients (p < 0.0001). Of 37 patients with very large defects (defect integral > 30), 78% were inducible, whereas only 30% of 33 patients with defect integrals < 5 were inducible. On multivariate analysis resting defect integral was an independent predictor of inducibility. In comparison with left ventricular ejection fraction (available in 122 patients), perfusion defect size was a better independent predictor of sustained VT on EPS. CONCLUSION: The presence or size of potentially ischemic myocardium does not appear to be related to the inducibility during EPS. Size of scar as quantified by myocardial perfusion imaging correlates well and better than the global left ventricular function with inducibility of sustained VT on EPS. PMID- 9362015 TI - Prognostic value of coronary angiography in patients with chronic ischemic left ventricular dysfunction and evidence of viable myocardium on thallium reinjection imaging. AB - BACKGROUND: We evaluated the independent and incremental prognostic value of cardiac catheterization and coronary angiographic data over thallium reinjection after stress redistribution imaging in patients with myocardial infarction and left ventricular dysfunction. METHODS AND RESULTS: Sixty-nine patients with a first myocardial infarction (> 8 weeks) and left ventricular ejection fraction < or = 40% underwent thallium-201 reinjection after stress redistribution tomographic imaging and cardiac catheterization. During follow-up (mean 26 months) 11 cardiac events (8 cardiac deaths and 3 nonfatal myocardial infarctions) occurred. On Cox regression analysis independent predictors of cardiac events were the sum of reversible and moderately irreversible defects at thallium reinjection (chi 2, 16.4, p < 0.005) and the number of reversible defects at stress redistribution (chi 2, 5.1, p < 0.05). Moreover, thallium reinjection imaging improved the prognostic power of clinical, exercise, and stress redistribution data (p < 0.01). The inclusion of left ventricular ejection fraction produced a borderline improvement (p = 0.06), whereas the number of vessels with coronary disease did not. In contrast, in patients at high risk such as those with at least 25% of viable myocardium at reinjection, the number of diseased vessels provided additional prognostic information (p < 0.05). CONCLUSIONS: In patients with chronic ischemic left ventricular dysfunction, left ventricular ejection fraction, but not the number of diseased vessels, provides additional prognostic information to thallium imaging. Therefore coronary angiography seems unnecessary in these patients, unless a significative amount of viable myocardium is detectable. PMID- 9362016 TI - Influence of prolonged exercise on myocardial distribution of 123I-MIBG in long distance runners. AB - BACKGROUND: A study was conducted to determine if prolonged exercise could provoke sympathetic neuronal alteration in an athlete's heart through assessment of myocardial distribution of 123I-metaiodobenzylguanidine (MIBG) in nine ultramarathon runners at baseline and after a 4-hour race. METHODS AND RESULTS: After injection of 370 MBq of 123I-MIBG, the athletes ran for 4 hours, covering 45 +/- 8 km. Planar and single-photon emission computed tomography (SPECT) images of the thorax were acquired at the end of the race. Two weeks later, studies at baseline were performed. A heart:mediastinum ratio (HMR) was calculated to quantify MIBG uptake. Basal MIBG studies showed normal myocardial tracer uptake, on both planar and SPECT images, and the HMR was 1.84 +/- 0.16. After the 4-hour race, MIBG studies showed decreased myocardial uptake in all athletes, and the HMR was 1.70 +/- 0.18 (p < 0.005). A positive correlation between the percentage of decrease of HMR after the race and the distance covered was observed (r = .910, p < 0.001). CONCLUSIONS: Myocardial MIBG activity is decreased by prolonged exercise in long-distance runners. The degree of reduction of myocardial MIBG activity is related to the distance covered. Prolonged exercise, as sustained sympathetic stimulus, may alter myocardial distribution of MIBG. PMID- 9362018 TI - Guidelines for preceptorship in nuclear cardiology laboratories. ASNC Training and Credentialing Committee. PMID- 9362017 TI - Risk-sensitive therapeutic strategies for coronary artery disease: toward testing driven therapy in stable angina patients with low-to-intermediate risk cardiac imaging results. PMID- 9362019 TI - Guidelines for technologist training in nuclear cardiology. ASNC Technologist Committee. PMID- 9362020 TI - Acute diffuse myocyte necrosis evidenced with 111In-antimyosin antibody scintigraphy in a patient with aortic stenosis. PMID- 9362021 TI - Nuclear cardiology in the literature. PMID- 9362022 TI - Reflections on nursing education. PMID- 9362024 TI - Preventing nursing student exposure incidents: the role of personal protective equipment and safety engineered devices. AB - This descriptive study used a self-selected sample of 580 newly licensed Virginia registered nurses to examine risk factors for percutaneous (needlestick) and mucocutaneous (splash) exposure incidents to blood or body fluids that occurred while they were nursing students. Fifty-one exposure incidents were reported by 42 respondents (7% of total). Twenty of 31 percutaneous exposure incidents were potentially preventable through the use of safety-engineered devices. Similarly, 4 of 10 mucocutaneous incidents occurring during routine procedures were potentially preventable through the use of personal protective equipment. Limited use of safety-engineered devices and personal protective equipment in the occurrence of nursing student exposure incidents suggests that active steps by schools of nursing to ensure student access to and use of personal protective equipment and safety-engineered devices may minimize exposure incident risk for students. PMID- 9362025 TI - Distance learning and nursing education. AB - This descriptive study investigated the use of distance learning programs in schools of nursing. Postcards were mailed to all members of the American Association of College of Nursing, asking them about distance learning at their schools. Seven schools were selected for further interviews. Of the 353 schools (80%) that responded, 135 schools (38%) reported offering off-site courses. Forty one schools reported plans for future offerings. The schools in this study offered a total of 33 master's and doctoral degrees by distance learning. A variety of media were used by the schools with the most common forms being one- and two-way video. Common themes identified from the interviews included faculty need for comfort, support, additional preparation time, and help developing courses. Student needs included structure, faculty contact, and a sense of belonging. The need for socialization was mentioned by all the informants. PMID- 9362023 TI - Nursing students' experiences caring for dying patients. AB - Since the 1960s nurse educators have been searching for the most effective approach to prepare nursing students for care of the dying. Studies investigating the effectiveness of death education programs for nursing students have reported inconsistent findings. A phenomenological study was conducted to explore the meaning of 26 undergraduate nursing students' experiences in caring for dying patients. The nursing students' written descriptions of their experiences were analyzed using Colaizzi's (1978) phenomenological method. Six themes emerged from this analysis. While caring for dying patients, nursing students experienced a gamut of emotions such as fear, sadness, frustration, and anxiety. Contemplation of the patient's life and death occurred as the students cared for their patients. In addition to providing physical, emotional, and spiritual support for dying patients, an integral part of nursing students' care involved supporting the patients' families. Helplessness was experienced by the students regarding their role as patient advocates. While caring for dying patients, nursing students' learning fluorished. Educational strategies for preparing nursing students to care for the dying are addressed based on the findings of this qualitative study. PMID- 9362026 TI - Unity and power: lessons from baccalaureate entry. AB - Education for nurses has been a contentious issue within and outside of the nursing profession since the American Nurses Association's 1965 support of the baccalaureate degree in nursing as basic educational criteria for the professional nurse (American Nurses Association, 1965). For 10 years, North Dakota has remained the only state to have achieved this educational goal, and North Dakota nurses have been able to defend this position against repeated challenges within the state since 1985. This article places nursing education within the context of the evolving, sweeping changes that are impacting all providers in the health care arena. The authors explain how and why North Dakota nurses were able to accomplish the standardization of nursing education for two levels of nurses: registered nurses and licensed practical nurses. The article describes the positive outcomes for nurses and clients that have occurred over the past 10 years. PMID- 9362027 TI - Cooperative learning: a model for teaching. AB - Cooperative learning provides a socially and intellectually stimulating model for the instruction of nursing students. It is one method of encouraging students to take responsibility for their own learning. Students are often able to explain a concept to another student in a unique way not used by faculty. This model harnesses and directs that student input in a constructive manner to increase achievement and accountability for all involved. Faculty must continue to examine how nursing is taught. The world is changing far too rapidly to do "business as usual." Cooperative learning is one strategy that can be used to motivate students to take active and responsible roles in their learning. PMID- 9362028 TI - Global consciousness in nursing: an ethnographic study of nurses with an international perspective. AB - Despite an ideal of international awareness, nursing education and professional organization have traditionally fostered social analysis within a rather local sphere of influence. However, there have always been renegade nurses whose idealism and global perspective have made them challenge the profession, adopt unusual career paths, or even leave nursing in favor of roles that more readily adapt to global awareness. Because the health care of the future demands an increasingly global-policy perspective, it is important to explore the relationship between the social structure of professional nursing and its ideological imperatives. This research employed ethnographic methods to study the experience of nurses involved in balancing what they perceived to be the discrepant perspectives of nursing and global awareness. The findings depict remarkable and inspiring careers within nursing and document the difficulties encountered by nurses in their attempts to apply global awareness to their professional nursing lives. Further, they generate practical implications for nursing education and professional organization to respond to the global trend toward primary health care policy and to prepare nurses to meet the inevitable challenges of the next millennium. PMID- 9362029 TI - A five-year study of graduates' performance on NCLEX-RN. AB - A 5-year study of graduates' performance on NCLEX-RN was conducted using data from July 1988 through February 1994. This time frame related to the "new" test plan introduced in 1988 with pass/fail results for NCLEX analysis. Using a quota sampling technique of 188 graduates, selected admission and curriculum variables and National League for Nursing (NLN) Comprehensive Achievement Test scores were studied in relationship to NCLEX-RN examination results. The strongest indicators of success were SAT verbal scores, nursing grade point average, and NLN Comprehensive Achievement Test scores. In addition, logistic regression analyses identified three nursing courses in combination with the NLN Comprehensive Achievement Test score as a strong model for prediction. Even though pass/fail data limit statistical analyses, the predictor variables were strong at P = 0.0001. These findings are consistent with prior studies. PMID- 9362031 TI - Alteration of anionic sites in renal glomerular basement membrane of pigs. AB - Ultrastructural alteration of anionic sites (ASs) in the glomerular basement membrane (GBM) was studied in 10 cases of swine mesangial proliferative glomerulonephritis using a cationic ultrastructural tracer, 0.5% polyethyleneimine (M.W. = 1,800). Glomerular ASs were seen as discrete electron dense particles in the GBM, mesangial matrix and epithelial cell surfaces by electron microscopy. In the lamina rara externa (LRE) of the normal GBM, ASs were distributed regularly in a single layer. In those areas of the LRE that contained electron dense deposits or clusters of spherical microparticles (SMPs), however, a distinct reduction or loss of ASs was observed in all the pigs. Quantitative assessment of ASs in the LRE over 1,000 nm of the GBM revealed a significant reduction in ASs in one case with diffuse global thickening of the GBM as compared with the remaining nine pigs without GBM thickening (P < 0.001, Mann Whitney's U-test). There were no ASs in the lamina densa (LD) of the normal GBM, but an irregular distribution of ASs was seen within the LD of the pig showing diffuse global thickening of the GBM. These results suggest that a disturbance of the charge-selective barrier in the GBM may be induced by electron-dense deposits or SMPs, in the LRE as well as thickening of the GBM in swine glomerulonephritis. PMID- 9362030 TI - A structured communication exercise to reduce nursing students' anxiety prior to entering the psychiatric setting. PMID- 9362032 TI - Hantavirus infection in SCID mice. AB - Severe combined immunodeficiency (SCID) mice were inoculated with Hantaan virus strain 76-118 (HTN) or Seoul virus strain SR-11 (SR) of hantaviruses. Susceptibility of SCID mice was compared with those of immunocompetent adult mice, newborn mice and nude mice. SCID mice inoculated with HTN or SR died 32 to 35 days after infection. Unlike newborn mice which also died of hantavirus infection, SCID mice survived longer than newborn mice and showed typical wasting symptoms rather than nervous symptoms. Immunohistochemical staining and virus isolation indicated that both HTN and SR inoculated SCID and SR inoculated nude mice showed systemic infection, but nude mice inoculated with SR survived for longer than 8 weeks after inoculation. Passive transfer of spleen cells from immunocompetent BALB/c mice conferred protection on SCID mice within 2 weeks of HTN infection. Immune mediated pathologic mechanism was examined by transferring the spleen cells to SCID mice inoculated with HTN virus 3 weeks before the cell transfer. The recipient SCID mice showed an increase of serum BUN level coinciding with the appearance of serum antibody to HTN virus, suggesting the immune mediated pathogenicity. PMID- 9362033 TI - Prevalence of Dirofilaria immitis infection in cats in Saitama, Japan. AB - To clarify Dirofilaria immitis infection among cats in Saitama Prefecture, Japan, 1,840 cats were examined postmortem for adult worms and microfilariae in the blood from 1989 to 1995. As a reference control, 500 dogs from the same area were examined in the same way and period. D. immitis worms were found in 15 cats, one of which had microfilariae in the blood. Prevalence rate of D. immitis infection was 0.8% (15/1,840) in cats and 46.8% (234/500) in dogs examined, whereas it was 4.1% and 64.6% in cats and dogs, respectively, aged 2 years and over. Worm burden per positive cat was 1.5 +/- 0.7 (mean +/- SD), the maximum number of worm was 3 in 2 cats, and 10 cats had a single worm each. All the worm-positive cats were tested for antibodies to feline immunodeficiency virus (FIV) and antigens of feline leukemia virus (FeLV) in sera. Positive rates of coinfection with D. immitis were 26.7% and 13.3% for FIV and FeLV, respectively. PMID- 9362035 TI - Frequency selectivity on aspirin-induced hearing loss in rats with auditory stimulus-induced conditioned suppression. AB - The conditioned suppression technique was employed to examine the acute effects of aspirin on auditory function in rats. Lever pressing behavior for water reinforcement was suppressed in the presence of an auditory stimulus that had been previously paired with electric shocks. A single intravenous injection of aspirin at a dose of 225 mg/kg caused an erroneous lever pressing response in the broad sound intensities of 2 kHz tone stimulus during the conditioned stimulus period. A statistically significant increase in the threshold for 2 kHz was found 1 to 72 hr after dosing but not for 4, 8 and 10 kHz. These results suggest that the hearing for low sound frequency in rats is vulnerable to the effects of aspirin. This paradigm in rats may be useful to further assess the different outer hair cells along the cochlear duct and provide an additional evidence for the aspirin ototoxicity research. PMID- 9362034 TI - Values of the serum components in Japanese black beef steers at farms with high productivity and low frequencies of disease and death in Miyazaki Prefecture. AB - Few reference values for use in metabolic profile tests for the maintenance of high productivity and the prevention of production diseases have been reported in Japanese Black beef cattle. To obtain basic data, 101 healthy steers at farms with high productivity and low frequencies of disease and death in Miyazaki Prefecture, Japan, were examined for the values of their serum components in this preliminary study. At the later fattening stage (5 to 20 months after introduction), statistically significant increases were observed in the mean serum activities of lactic dehydrogenase, glutamic-oxalacetic transaminase, gamma glutamyl transpeptidase, and creatine phosphokinase, the mean serum contents of triglyceride, total cholesterol, albumin (Alb), total protein, blood urea nitrogen, magnesium, and vitamin E, and the mean serum calcium (Ca)/inorganic phosphorus (IP) ratio, and statistically significant decreases were seen in the mean serum alkaline phosphatase activity and the mean serum contents of glucose, IP, and vitamin A. The mean serum Alb/globulin ratio and the mean serum Ca and nonesterified fatty acids contents demonstrated no statistically significant changes. PMID- 9362036 TI - The afferent activity of the superior laryngeal nerve, and respiratory reflexes specifically responding to intralaryngeal pressure changes in anesthetized Shiba goats. AB - This study was aimed at characterizing the superior laryngeal nerve (SLN) afferent activities under four different respiratory conditions, i.e., tracheostomy breathing (TB), upper airway breathing (UAB), tracheal occlusion (TO) and upper airway occlusion (UAO), and investigating respiratory changes in response to transmural pressures applied to the larynx in anesthetized Shiba goats. The activity recorded from the whole SLN increased at both inspiration and expiration during TB, UAB and TO, while an expiratory augmentation accompanied by an inspiratory inhibition was found during UAO. Based on recordings from 109 thin filament-preparations, 47 units were identified as 'drive' receptors, 31 as 'pressure' receptors (22 'positive' and 9 'negative' pressure receptors), and the rest 31 as 'non-modulated type' of receptors. The posterior cricoarytenoid (PCA) muscle activity showed a clear inspiratory modulation during UAB and was significantly enhanced by negative pressure applied to the isolated upper airway, where such an augmented activity was abolished by bilateral section of the SLN. No significant changes were found in the respiratory cycle during application of negative pressures to the larynx. The respiratory modulation of the SLN in Shiba goats was essentially identical to that reported for rabbits, rats and guinea pigs, but not in dogs. The reflex response of the upper airway muscles to the laryngeal pressure changes in Shiba goats were found to be less noticeable than in rabbits and dogs. PMID- 9362037 TI - Effects of 6-chloro-2',3'-dideoxyguanosine (6-Cl-ddG) in surface lymph nodes of rhesus monkeys (Macaca mulatta) chronically infected with simian immunodeficiency virus (SIVmac239). AB - We studied the effects of 6-chloro-2',3'-dideoxyguanosine (6-Cl-ddG), an antiretroviral drug, in surface lymph nodes of rhesus monkeys (Macaca mulatta) chronically infected with simian immunodeficiency virus (SIV). The rhesus monkeys were treated with 25 mg/kg of 6-Cl-ddG every 8 hr for 2 weeks. We performed sequential biopsies of the surface lymph nodes three times: before, during, and after the drug treatment. The 6-Cl-ddG dramatically decreased the number of infectious virus (measured by limiting dilution assay) in lymph node mononuclear cells. This decrease was consistent with the decrease in the number of viral RNA positive cells in lymph nodes (analyzed by in situ hybridization). Histopathological analysis revealed that hyperplastic lymphoid follicles were reduced in size, especially, enlarged areas of centroblasts in lymphoid follicles (the so-called dark areas of germinal centers) were declined. Our results demonstrated that 6-Cl-ddG decreased the viral burden concomitantly with reduced hyper-activation of germinal centers in lymphoid follicles of SIV-infected rhesus monkeys. PMID- 9362038 TI - Sialadenitis in IQI/Jic mice: a new animal model of Sjogren's syndrome. AB - Focal infiltration of lymphocytes with parenchymal destruction was noted in both salivary and lacrimal glands of IQI/Jic mice. The sialadenitis was found in more than 80% of female mice at all ages examined. The lesion progressed after 6 months and became more prominent with age. In contrast, male mice had slight and stable salivary lesions independent of age, though the incidence increased with age. Infiltrating lymphocytes consisted of both T and B cells. The dominant lymphocytes in small foci were CD4+ cells, but the majority of infiltrating cells were B cells (B220+), followed by CD4+ T cells in larger lesions. The ductual epithelium in the foci aberrantly expressed MHC class II antigen. Eight of 24 15 month-old female mice with sialadenitis produced speckled-type IgG antinuclear autoantibody. These findings are similar to those in patients with Sjogren's syndrome. IQI/Jic mice could be a novel animal model of Sjoren's syndrome. PMID- 9362040 TI - Effects of central nervous stimulants on spino-bulbo-spinal reflex potentials in cats. AB - Effects of central nervous stimulants on the spino-bulbo-spinal reflex potential were evaluated in anesthetized intact cats, and compared with those on segmental spinal reflex potentials in anesthetized spinal cats. In spinal cats, strychnine augmented polysynaptic reflex potential, picrotoxin inhibited dorsal root reflex potential, aminopyrine potentiated mono- and poly-synaptic reflex potentials but inhibited dorsal root reflex potential, and 4-aminopyridine potentiated all the three types of segmental reflex potentials. A combination of fenbufen, a non steroidal antiinflammatory agent, and enoxacin, a new quinolone antimicrobial, inhibited all the three types of segmental reflex potentials. In contrast, all these drugs consistently produced an augmentation of the spino-bulbo-spinal reflex potential in anesthetized intact cats. From these findings, we suggest that the spino-bulbo-spinal reflex potential may be used as an electrophysiological parameter for the evaluation of central nervous stimulants. PMID- 9362039 TI - The age dependent levels of serum ALP isoenzymes and the diagnostic significance of corticosteroid-induced ALP during long-term glucocorticoid treatment. AB - Three isoenzymes of total alkaline phosphatase (TALP) are known in canine serum: Bone alkaline phosphatase (BALP), liver alkaline phosphatase (LALP) and corticosteroid-induced alkaline phosphatase (CALP). Using an assay developed by combining selective precipitation of BALP by wheat germ lectin (WGA) and an automated levamisole inhibition method for quantifying CALP, age-related reference ranges of the isoenzymes in 75 canine serum samples were investigated. BALP comprised 96, 38 and 26% of TALP in young, middle aged and old dogs, respectively, and CALP was respectively 12, 11 and 27% of TALP. LALP was less than 10% in the young but represented more than 50% of TALP in middle aged and old dogs. Furthermore, the significance of monitoring LALP and CALP and their relationship to hepatopathy in dogs receiving long term prednisolone therapy was assessed. In this study, TALP increased in all dogs receiving prednisolone. But only LALP was responsible in dogs with minor vacuolization of the liver, while in severely degenerated cases both LALP and CALP increased. It is concluded that a high TALP due solely to LALP, rather than LALP and CALP represents lesser liver pathologic involvement. Monitoring the 2 isoenzymes has greater significancy in assessing in the level of liver damage than relying on an increased TALP value alone. Quantifying the individual isoenzymes may further be useful in assessing the clinical significance of these isoenzymes in various conditions that result in elevated TALP values. PMID- 9362042 TI - Loss of glycosylation at Asn144 alters the substrate preference of the N8 influenza A virus neuraminidase. AB - Role of asparagine-linked (N-linked) oligosaccharide side chains in the maturation and the function of influenza virus neuraminidase (NA) subtype N8 was examined by site-directed mutagenesis and vaccinia virus expression system. Mutations in the consensus sequence for N-linked glycosylation at Asn 84 or 398 prevent the proper maturation of mutant NAs. On the contrary, mutation at Asn 144, that is conserved in all except two strains of influenza virus NA ever sequenced, did not affect the proper maturation and the transport of the mutant NA to the cell surface. Furthermore, this mutation led the alternation of substrate preference of this enzyme. These observations indicate that N glycosylation at Asn 144 of N8 NA may be conserved from the functional requirement, but not from the structural necessity. PMID- 9362043 TI - Circulating tumor necrosis factor and interleukin-1 after administration of LPS in adult cows. AB - This study examined the levels of serum tumor necrosis factor (TNF), interleukin 1 (IL-1) and plasma cortisol levels in adult cows after intravenous administration of lipopolysaccharide (LPS) extracted from Escherichia coli. The adult cows exhibited clinical signs of endotoxic shock. The mean concentrations of serum TNF was 557.9 U/ml and serum IL-1 was 90.6 U/ml at 2 hr after LPS administration following severe endotoxic shock. Plasma cortisol concentrations increased immediately and a peak level was 131.4 ng/ml at 1 hr after LPS challenge. These results suggested that circulating concentrations of TNF, IL-1, and cortisol may be associated with clinical signs of endotoxemia in adult cows. PMID- 9362041 TI - Effect of oral egg antibody in experimental F18+ Escherichia coli infection in weaned pigs. AB - The protection conferred by egg antibody specific for F18-fimbriae against infection with F18+ Escherichia coli was studied in controlled passive immunization trials involving weaned pigs. Parameters of protection consisted of body weight gain, frequency and severity of diarrhea and recovery of the challenge strain of F18+ E. coli. Weaned pigs at four weeks of age were challenge exposed once daily for three days by oral inoculation with 10(11) cfu of virulent F18+ E. coli followed by daily administration of antibody supplemented feed for 9 days starting from the first challenge day 0. Results showed a dose-dependent response to antibody treatment. The group of pigs given 1:50 titer of antibody in feed had less frequency of diarrhea (P < 0.01-0.05), higher rate of gain (P < 0.01) and lower isolation rate of challenge strain in rectal and intestinal swabs (P < 0.01) compared to non-treated control. In the same manner, the anti-F18 antibody significantly reduced adherence of F18+ E. coli to pig intestinal epithelial cells in vitro (P < 0.01). Results suggest that egg antibodies specific for the F18 fimbriae is a suitable immunotherapeutic agent for pigs infected with F18+ E. coli and that pigs can be protected from overt clinical disease and the subsequent reduced performance arising from infection with this pathogen. PMID- 9362044 TI - Lectin histochemical characteristics of the epithelial surface of ileal Peyer's patches in 3-week-old pigs. AB - Distinct glycoconjugate expression between dome enterocytes and villus enterocytes in ileum from twelve 3-week-old conventional pigs was examined by the use of twenty one biotinylated lectins with avidin-biotin-peroxidase complex method. Three patterns of staining were seen. First, lectins bind to dome enterocyte and villus enterocyte to approximately equal staining, i.e. DSL, WGA, s-WGA and ConA. Second, lectins display a markedly higher affinity for villus enterocyte than dome enterocyte, i.e. DBA, SBA, RCA I, SJA, VVA, BSL II, LEL, PNA, Jacalin, and ECL. Third, lectins exhibit negative staining to dome enterocyte only, i.e. PSA, LCA, UEA-I, and STL. Four lectins; PSA, LCA, UEA-I, STL may be useful negative marker to differentiate glycoconjugate expression between dome enterocyte and villus enterocyte. The staining patterns are slightly different among these negative markers. Three lectins, PSA, LCA, and UEA-1, are negative marker to differentiate dome enterocytes and villus enterocytes. But STL is also negative to dome epithelial surface and moderately positive to villus brush border. It is suggested that the present lectin-binding studies provide the marker of dome enterocyte as compared with villus enterocytes. PMID- 9362045 TI - Genetic analysis of equine methicillin-resistant Staphylococcus aureus by pulsed field gel electrophoresis. AB - Pulsed-field gel electrophoresis (PFGE) was used to determine genetic relationships among 15 methicillin-resistant Staphylococcus aureus (MRSA) isolates from mares with metritis and from a stallion with dermatitis in Hokkaido. All the 15 isolates showed phage pattern 6/47/54/75, coagulase type IV, and enterotoxin type A. The restriction endonuclease SmaI cut their genomic DNAs into 15 or 16 fragments ranging in size from 8 to 630 kb. Fourteen of the 15 isolates showed the same PFGE pattern, whereas the remaining one appeared to be closely related. The 9 human MRSA isolates showing the same phenotypic characteristics as the horse isolates gave different PFGE patterns from those of the horse isolates. PMID- 9362046 TI - A control of a golden retriever with renal dysplasia. AB - A six-month-old male Golden Retriever with a three-month history of polyuria and polydipsia was examined. Hematological examinations revealed nonregenerative anemia, azotemia, high serum creatinine level, hypercalcemia, hyperphosphatemia, hypercholesterolemia, hyperamylasemia, and low level of total serum protein. Urinalysis indicated mild proteinuria, and low specific gravity. Radiographic and ultrasonographic examinations revealed bilateral small sized kidneys. Histological examination by renal biopsy confirmed the diagnosis of renal dysplasia. Treatment with a dietary protein restriction, oral adsorbents, and dried aluminum hydroxide gel have been performed in this dog, and then, azotemia, high serum creatinine level, hypercalcemia, and hyperphosphatemia were improved. During 10 months after the initiation of treatments, no significant clinical change except polydipsia and polyuria has been observed. PMID- 9362049 TI - Glomus tumor in a dog. AB - A mass of glomus tumor was found on the skin of the right foreleg of a ten-year old male mongrel dog. Histologically the mass contained some vasculatures and sheet-like proliferation of epithelioid tumor cells. Some blood vessels were rimmed by the tumor cells, which had a round to ovoid nucleus and plump eosinophilic cytoplasm. Immunohistochemically, smooth muscle actin and vimentin were demonstrated in the tumor cells. By electron microscopic examination, actin like filaments with dense bodies were observed in the cytoplasm of the tumor cells. This is the first case report of a canine glomus tumor. PMID- 9362048 TI - Pathological findings of nude mice inoculated with bovine Neospora. AB - Nude mice were infested with bovine Neospora by intraperitoneal inoculation of the brain and spinal cord from an aborted bovine fetus due to neosporosis. Inoculated mice showed severe emaciation and tetraplegia at about 2 to 4 months post-inoculation. Histopathologically, polyradiculoneuritis and peripheral neuritis were the major findings, and lesions in the central nervous system were located at periventricular and submeningeal areas of the cerebrum or at the white matter around the roots of radices of the spinal cord. These findings may suggest the protozoa inoculated into the abdominal cavity invaded the spinal cord via the spinal nerve and later reached the brain through the cerebrospinal fluid. PMID- 9362047 TI - Hemagglutination with equine arteritis virus. AB - Equine arteritis virus (EAV) grown on RK13 cell cultures was tested for hemagglutination (HA) with erythrocytes from a variety of species at 4 degrees C, room temperature and 37 degrees C. HA was observed at all temperatures with erythrocytes from mouse and chicken but not with those of cattle, horse, rabbit, guinea pig, mongolian gerbil, goose or chick embryo. Chickens showed an individual variation in agglutinability of their erythrocytes, requiring selection of birds to obtain erythrocytes for HA. The HA activity was enhanced by treatment of virus materials with Tween 80 followed by treatment with ether. The HA reaction was inhibited by specific antiserum. Higher HA-inhibiting (HI) antibody titers were obtained by the incubation of serum-HA antigen mixture at 4 degrees C for 24 hr. HI antibody titers of individual horse sera showed a significant positive correlation with their neutralizing antibody titers. PMID- 9362051 TI - Sporicidal activities of disinfectants on Paenibacillus larvae. AB - Sporicidal activities of glutaraldehyde, sodium hypochlorite, povidone iodine, ethylene oxide gas, chlorhexidine gluconate, and didecyl dimethylammonium chloride on wet and dry spores of Paenibacillus larvae (basonym: Bacillus larvae) were evaluated for control of honeybee American foulbrood. Glutaraldehyde was found to have a strong and rapid effect on both the wet and the dry spores among the disinfectants tested. PMID- 9362052 TI - First record of Eustrongylides tubifex (Dioctophymatidae) from little grebe, Tachybaptus ruficollis in Japan. AB - A nematode species belonging to the genus Eustrongylides (Dioctophymatidae) was obtained from the proventriculus of Tachybaptus ruficollis, found in December, 1995 in Kobe City, Hyogo Prefecture, Japan. Observation under a scanning electron microscope to investigate anterior extremity with the labial papillae in two circles showed that this species is identical to E. tubifex. This is the first record of this species in Japan. PMID- 9362050 TI - Rhythmical discharges recorded from cervical and trunk muscle nerves produced by stimulation of mesencephalic locomotor region (MLR) in the decerebrated cat. AB - This experiment investigated the effects of mesencephalic locomotor region (MLR) stimulation on cervical and trunk motoneurons in decerebrated cats. The experiments were performed on 28 adult cats (2.1-3.9 kg) of either sex. Stimulation of MLR produced the rhythmical discharge of muscle nerves of the splenius (SP), the longissimus lumborum (LL) and the obliquus externus abdominis (OEA). There was a close relationship between rhythmical discharge of SP, LL or OEA muscle nerve and hindlimb muscle nerve. This fact suggests that rhythmical discharges of cervical and trunk muscle nerves relate to locomotion. PMID- 9362053 TI - Plasma thymidine kinase activity in dogs with lymphoma and leukemia. AB - Plasma thymidine kinase (TK) activity was evaluated as a plasma marker for canine lymphoma and leukemia. A tentative "cut-off" value was set at 6.0 U/l as the upper level of plasma TK based on the mean + 2SD of plasma TK activity in 13 clinically healthy dogs. The levels of plasma TK activity in all of the 20 dogs with lymphoma and leukemia were higher than the cut-off value, whereas those in dogs with lymphoma decreased in parallel with the reduction of the tumor mass after chemotherapy. These findings suggested that estimation of plasma TK activity can be used as a plasma marker for lymphoma and leukemia in the dog. PMID- 9362054 TI - Plasma levels of diethylcarbamazine and their effects on implanted microfilariae of Brugia pahangi in rats. AB - Plasma level of diethylcarbamazine (DEC) was measured by using gas chromatography and was compared to the changes of microfilaremia after an intraperitoneal injection with 200 mg/kg of DEC in rats. The microfilaremia was induced artificially by an intravenous implantation with 2 x 10(5) Brugia pahangi microfilariae (mf) 1 day before DEC treatment. The rats treated with DEC showed a rapid and significant decrease in mf number in the circulation within 30 min, continued for 4 hr, and then increased rapidly. DEC seemed to cause transient but significant suppression of microfilaremia of B. pahangi in rats directly. PMID- 9362055 TI - E.E. Just Lecture, 1996. Conus venom peptides, receptor and ion channel targets, and drug design: 50 million years of neuropharmacology. PMID- 9362056 TI - Cholesterol-independent targeting of Golgi membrane proteins in insect cells. AB - Distinct lipid compositions of intracellular organelles could provide a physical basis for targeting of membrane proteins, particularly where transmembrane domains have been shown to play a role. We tested the possibility that cholesterol is required for targeting of membrane proteins to the Golgi complex. We used insect cells for our studies because they are cholesterol auxotrophs and can be depleted of cholesterol by growth in delipidated serum. We found that two well-characterized mammalian Golgi proteins were targeted to the Golgi region of Aedes albopictus cells, both in the presence and absence of cellular cholesterol. Our results imply that a cholesterol gradient through the secretory pathway is not required for membrane protein targeting to the Golgi complex, at least in insect cells. PMID- 9362057 TI - Nuclear pore complex number and distribution throughout the Saccharomyces cerevisiae cell cycle by three-dimensional reconstruction from electron micrographs of nuclear envelopes. AB - The number of nuclear pore complexes (NPCs) in individual nuclei of the yeast Saccharomyces cerevisiae was determined by computer-aided reconstruction of entire nuclei from electron micrographs of serially sectioned cells. Nuclei of 32 haploid cells at various points in the cell cycle were modeled and found to contain between 65 and 182 NPCs. Morphological markers, such as cell shape and nuclear shape, were used to determine the cell cycle stage of the cell being examined. NPC number was correlated with cell cycle stage to reveal that the number of NPCs increases steadily, beginning in G1-phase, suggesting that NPC assembly occurs continuously throughout the cell cycle. However, accumulation of nuclear envelope observed during the cell cycle, indicated by nuclear surface area, is not continuous at the same rate, such that the density of NPCs per unit area of nuclear envelope peaks in apparent S-phase cells. Analysis of the nuclear envelope reconstructions also revealed no preferred NPC-to-NPC distance. However, NPCs were found in large clusters over regions of the nuclear envelope. Interestingly, clusters of NPCs were most pronounced in early mitotic nuclei and were found to be associated with the spindle pole bodies, but the functional significance of this association is unknown. PMID- 9362059 TI - Coordinate regulation of G- and C strand length during new telomere synthesis. AB - We have used the ciliate Euplotes to study the role of DNA polymerase in telomeric C strand synthesis. Euplotes provides a unique opportunity to study C strand synthesis without the complication of simultaneous DNA replication because millions of new telomeres are made at a stage in the life cycle when no general DNA replication takes place. Previously we showed that the C-strands of newly synthesized telomeres have a precisely controlled length while the G-strands are more heterogeneous. This finding suggested that, although synthesis of the G strand (by telomerase) is the first step in telomere addition, a major regulatory step occurs during subsequent C strand synthesis. We have now examined whether G- and C strand synthesis might be regulated coordinately rather than by two independent mechanisms. We accomplished this by determining what happens to G- and C strand length if C strand synthesis is partially inhibited by aphidicolin. Aphidicolin treatment caused a general lengthening of the G-strands and a large increase in C strand heterogeneity. This concomitant change in both the G- and C strand length indicates that synthesis of the two strands is coordinated. Since aphidicolin is a very specific inhibitor of DNA pol alpha and pol delta, our results suggest that this coordinate length regulation is mediated by DNA polymerase. PMID- 9362058 TI - Distinct endocytic responses of heteromeric and homomeric transforming growth factor beta receptors. AB - Transforming growth factor beta (TGF beta) family ligands initiate a cascade of events capable of modulating cellular growth and differentiation. The receptors responsible for transducing these cellular signals are referred to as the type I and type II TGF beta receptors. Ligand binding to the type II receptor results in the transphosphorylation and activation of the type I receptor. This heteromeric complex then propagates the signal(s) to downstream effectors. There is presently little data concerning the fate of TGF beta receptors after ligand binding, with conflicting reports indicating no change or decreasing cell surface receptor numbers. To address the fate of ligand-activated receptors, we have used our previously characterized chimeric receptors consisting of the ligand binding domain from the granulocyte/macrophage colony-stimulating factor alpha or beta receptor fused to the transmembrane and cytoplasmic domain of the type I or type II TGF beta receptor. This system not only provides the necessary sensitivity and specificity to address these types of questions but also permits the differentiation of endocytic responses to either homomeric or heteromeric intracellular TGF beta receptor oligomerization. Data are presented that show, within minutes of ligand binding, chimeric TGF beta receptors are internalized. However, although all the chimeric receptor combinations show similar internalization rates, receptor down-regulation occurs only after activation of heteromeric TGF beta receptors. These results indicate that effective receptor down-regulation requires cross-talk between the type I and type II TGF beta receptors and that TGF beta receptor heteromers and homomers show distinct trafficking behavior. PMID- 9362060 TI - Induction of a G2-phase arrest in Xenopus egg extracts by activation of p42 mitogen-activated protein kinase. AB - Previous work has established that activation of Mos, Mek, and p42 mitogen activated protein (MAP) kinase can trigger release from G2-phase arrest in Xenopus oocytes and oocyte extracts and can cause Xenopus embryos and extracts to arrest in mitosis. Herein we have found that activation of the MAP kinase cascade can also bring about an interphase arrest in cycling extracts. Activation of the cascade early in the cycle was found to bring about the interphase arrest, which was characterized by an intact nuclear envelope, partially condensed chromatin, and interphase levels of H1 kinase activity, whereas activation of the cascade just before mitosis brought about the mitotic arrest, with a dissolved nuclear envelope, condensed chromatin, and high levels of H1 kinase activity. Early MAP kinase activation did not interfere significantly with DNA replication, cyclin synthesis, or association of cyclins with Cdc2, but it did prevent hyperphosphorylation of Cdc25 and Wee1 and activation of Cdc2/cyclin complexes. Thus, the extracts were arrested in a G2-like state, unable to activate Cdc2/cyclin complexes. The MAP kinase-induced G2 arrest appeared not to be related to the DNA replication checkpoint and not to be mediated through inhibition of Cdk2/cyclin E; evidently a novel mechanism underlies this arrest. Finally, we found that by delaying the inactivation of MAP kinase during release of a cytostatic factor-arrested extract from its arrest state, we could delay the subsequent entry into mitosis. This finding suggests that it is the persistence of activated MAP kinase after fertilization that allows the occurrence of a G2 phase during the first mitotic cell cycle. PMID- 9362062 TI - Synthesis and turnover of embryonic sea urchin ciliary proteins during selective inhibition of tubulin synthesis and assembly. AB - When ciliogenesis first occurs in sea urchin embryos, the major building block proteins, tubulin and dynein, exist in substantial pools, but most 9 + 2 architectural proteins must be synthesized de novo. Pulse-chase labeling with [3H]leucine demonstrates that these proteins are coordinately up-regulated in response to deciliation so that regeneration ensues and the tubulin and dynein pools are replenished. Protein labeling and incorporation into already-assembled cilia is high, indicating constitutive ciliary gene expression and steady-state turnover. To determine whether either the synthesis of tubulin or the size of its available pool is coupled to the synthesis or turnover of the other 9 + 2 proteins in some feedback manner, fully-ciliated mid- or late-gastrula stage Strongylocentrotus droebachiensis embryos were pulse labeled in the presence of colchicine or taxol at concentrations that block ciliary growth. As a consequence of tubulin autoregulation mediated by increased free tubulin, no labeling of ciliary tubulin occurred in colchicine-treated embryos. However, most other proteins were labeled and incorporated into steady-state cilia at near-control levels in the presence of colchicine or taxol. With taxol, tubulin was labeled as well. An axoneme-associated 78 kDa cognate of the molecular chaperone HSP70 correlated with length during regeneration; neither colchicine nor taxol influenced the association of this protein in steady-state cilia. These data indicate that 1) ciliary protein synthesis and turnover is independent of tubulin synthesis or tubulin pool size; 2) steady-state incorporation of labeled proteins cannot be due to formation or elongation of cilia; 3) substantial tubulin exchange takes place in fully-motile cilia; and 4) chaperone presence and association in steady-state cilia is independent of background ciliogenesis, tubulin synthesis, and tubulin assembly state. PMID- 9362061 TI - Distinct molecular events during secretory granule biogenesis revealed by sensitivities to brefeldin A. AB - The biogenesis of peptide hormone secretory granules involves a series of sorting, modification, and trafficking steps that initiate in the trans-Golgi and trans-Golgi network (TGN). To investigate their temporal order and interrelationships, we have developed a pulse-chase protocol that follows the synthesis and packaging of a sulfated hormone, pro-opiomelanocortin (POMC). In AtT-20 cells, sulfate is incorporated into POMC predominantly on N-linked endoglycosidase H-resistant oligosaccharides. Subcellular fractionation and pharmacological studies confirm that this sulfation occurs at the trans Golgi/TGN. Subsequent to sulfation, POMC undergoes a number of molecular events before final storage in dense-core granules. The first step involves the transfer of POMC from the sulfation compartment to a processing compartment (immature secretory granules, ISGs): Inhibiting export of pulse-labeled POMC by brefeldin A (BFA) or a 20 degrees C block prevents its proteolytic conversion to mature adrenocorticotropic hormone. Proteolytic cleavage products were found in vesicular fractions corresponding to ISGs, suggesting that the processing machinery is not appreciably activated until POMC exits the sulfation compartment. A large portion of the labeled hormone is secreted from ISGs as incompletely processed intermediates. This unregulated secretory process occurs only during a limited time window: Granules that have matured for 2 to 3 h exhibit very little unregulated release, as evidenced by the efficient storage of the 15-kDa N-terminal fragment that is generated by a relatively late cleavage event within the maturing granule. The second step of granule biogenesis thus involves two maturation events: proteolytic activation of POMC in ISGs and a transition of the organelle from a state of high unregulated release to one that favors intracellular storage. By using BFA, we show that the two processes occurring in ISGs may be uncoupled: although the unregulated secretion from ISGs is impaired by BFA, proteolytic processing of POMC within this organelle proceeds unaffected. The finding that BFA impairs constitutive secretion from both the TGN and ISGs also suggests that these secretory processes may be related in mechanism. Finally, our data indicate that the unusually high levels of unregulated secretion often associated with endocrine tumors may result, at least in part, from inefficient storage of secretory products at the level of ISGs. PMID- 9362063 TI - Electron tomography of metaphase nucleolar organizer regions: evidence for a twisted-loop organization. AB - Metaphase nucleolar organizer regions (NORs), one of four types of chromosome bands, are located on human acrocentric chromosomes. They contain r-chromatin, i.e., ribosomal genes complexed with proteins such as upstream binding factor and RNA polymerase I, which are argyrophilic NOR proteins. Immunocytochemical and cytochemical labelings of these proteins were used to reveal r-chromatin in situ and to investigate its spatial organization within NORs by confocal microscopy and by electron tomography. For each labeling, confocal microscopy revealed small and large double-spotted NORs and crescent-shaped NORs. Their internal three dimensional (3D) organization was studied by using electron tomography on specifically silver-stained NORs. The 3D reconstructions allow us to conclude that the argyrophilic NOR proteins are grouped as a fiber of 60-80 nm in diameter that constitutes either one part of a turn or two or three turns of a helix within small and large double-spotted NORs, respectively. Within crescent-shaped NORs, virtual slices reveal that the fiber constitutes several longitudinally twisted loops, grouped as two helical 250- to 300-nm coils, each centered on a nonargyrophilic axis of condensed chromatin. We propose a model of the 3D organization of r-chromatin within elongated NORs, in which loops are twisted and bent to constitute one basic chromatid coil. PMID- 9362064 TI - Polymer models of meiotic and mitotic chromosomes. AB - Polymers tied together by constraints exhibit an internal pressure; this idea is used to analyze physical properties of the bottle-brush-like chromosomes of meiotic prophase that consist of polymer-like flexible chromatin loops, attached to a central axis. Using a minimal number of experimental parameters, semiquantitative predictions are made for the bending rigidity, radius, and axial tension of such brushes, and the repulsion acting between brushes whose bristles are forced to overlap. The retraction of lampbrush loops when the nascent transcripts are stripped away, the oval shape of diplotene bivalents between chiasmata, and the rigidity of pachytene chromosomes are all manifestations of chromatin pressure. This two-phase (chromatin plus buffer) picture that suffices for meiotic chromosomes has to be supplemented by a third constituent, a chromatin glue to understand mitotic chromosomes, and explain how condensation can drive the resolution of entanglements. This process resembles a thermal annealing in that a parameter (the affinity of the glue for chromatin and/or the affinity of the chromatin for buffer) has to be tuned to achieve optimal results. Mechanical measurements to characterize this protein-chromatin matrix are proposed. Finally, the propensity for even slightly chemically dissimilar polymers to phase separate (cluster like with like) can explain the apparent segregation of the chromatin into A + T- and G + C-rich regions revealed by chromosome banding. PMID- 9362065 TI - Heterogeneous distribution of the unusual phospholipid semilysobisphosphatidic acid through the Golgi complex. AB - To investigate the distribution of lipids through the Golgi complex, we analyzed the envelopes of several viruses that assemble in different subcompartments of the Golgi, as well as subcellular fractions. Our results indicate that each Golgi subcompartment has a distinct phospholipid composition due mainly to differences in the relative amounts of semilysobisphosphatidic acid (SLBPA), sphingomyelin, phosphatidylserine, and phosphatidylinositol. Interestingly, SLBPA is enriched in the adjacent Golgi networks compared with the Golgi stack, and this enrichment varies with cell type. The heterogeneous distribution of SLBPA through the Golgi complex suggests it may play an important role in the structure and/or function of this organelle. PMID- 9362066 TI - Galectin-4 and small intestinal brush border enzymes form clusters. AB - Detergent-insoluble complexes prepared from pig small intestine are highly enriched in several transmembrane brush border enzymes including aminopeptidase N and sucrase-isomaltase, indicating that they reside in a glycolipid-rich environment in vivo. In the present work galectin-4, an animal lectin lacking a N terminal signal peptide for membrane translocation, was discovered in these complexes as well, and in gradient centrifugation brush border enzymes and galectin-4 formed distinct soluble high molecular weight clusters. Immunoperoxidase cytochemistry and immunogold electron microscopy showed that galectin-4 is indeed an intestinal brush border protein; we also localized galectin-4 throughout the cell, mainly associated with membraneous structures, including small vesicles, and to the rootlets of microvillar actin filaments. This was confirmed by subcellular fractionation, showing about half the amount of galectin-4 to be in the microvillar fraction, the rest being associated with insoluble intracellular structures. A direct association between the lectin and aminopeptidase N was evidenced by a colocalization along microvilli in double immunogold labeling and by the ability of an antibody to galectin-4 to coimmunoprecipitate aminopeptidase N and sucrase-isomaltase. Furthermore, galectin-4 was released from microvillar, right-side-out vesicles as well as from mucosal explants by a brief wash with 100 mM lactose, confirming its extracellular localization. Galectin-4 is therefore secreted by a nonclassical pathway, and the brush border enzymes represent a novel class of natural ligands for a member of the galectin family. Newly synthesized galectin-4 is rapidly "trapped" by association with intracellular structures prior to its apical secretion, but once externalized, association with brush border enzymes prevents it from being released from the enterocyte into the intestinal lumen. PMID- 9362067 TI - Integrin alpha 6A beta 1 induces CD81-dependent cell motility without engaging the extracellular matrix migration substrate. AB - It is well established that integrins and extracellular matrix (ECM) play key roles in cell migration, but the underlying mechanisms are poorly defined. We describe a novel mechanism whereby the integrin alpha 6 beta 1, a laminin receptor, can affect cell motility and induce migration onto ECM substrates with which it is not engaged. By using DNA-mediated gene transfer, we expressed the human integrin subunit alpha 6A in murine embryonic stem (ES) cells. ES cells expressing alpha 6A (ES6A) at the surface dimerized with endogenous beta 1, extended numerous filopodia and lamellipodia, and were intensely migratory in haptotactic assays on laminin (LN)-1. Transfected alpha 6A was responsible for these effects, because cells transfected with control vector or alpha 6B, a cytoplasmic domain alpha 6 isoform, displayed compact morphology and no migration, like wild-type ES cells. The ES6A migratory phenotype persisted on fibronectin (Fn) and Ln-5. Adhesion inhibition assays indicated that alpha 6 beta 1 did not contribute detectably to adhesion to these substrates in ES cells. However, anti-alpha 6 antibodies completely blocked migration of ES6A cells on Fn or Ln-5. Control experiments with monensin and anti-ECM antibodies indicated that this inhibition could not be explained by deposition of an alpha 6 beta 1 ligand (e.g., Ln-1) by ES cells. Cross-linking with secondary antibody overcame the inhibitory effect of anti-alpha 6 antibodies, restoring migration or filopodia extension on Fn and Ln-5. Thus, to induce migration in ES cells, alpha 6A beta 1 did not have to engage with an ECM ligand but likely participated in molecular interactions sensitive to anti-alpha 6 beta 1 antibody and mimicked by cross linking. Antibodies to the tetraspanin CD81 inhibited alpha 6A beta 1-induced migration but had no effect on ES cell adhesion. It is known that CD81 is physically associated with alpha 6 beta 1, therefore our results suggest a mechanism by which interactions between alpha 6A beta 1 and CD81 may up-regulate cell motility, affecting migration mediated by other integrins. PMID- 9362069 TI - Degradation of hepatic stearyl CoA delta 9-desaturase. AB - delta 9-Desaturase is a key enzyme in the synthesis of desaturated fatty acyl CoAs. Desaturase is an integral membrane protein induced in the endoplasmic reticulum by dietary manipulations and then rapidly degraded. The proteolytic machinery that specifically degrades desaturase and other short-lived proteins in the endoplasmic reticulum has not been identified. As the first step in identifying cellular factors involved in the degradation of desaturase, liver subcellular fractions of rats that had undergone induction of this enzyme were examined. In livers from induced animals, desaturase was present in the microsomal, nuclear (P-1), and subcellular fractions (P-2). Incubation of desaturase containing fractions at physiological pH and temperature led to the complete disappearance of the enzyme. Washing microsomes with a buffer containing high salt decreased desaturase degradation activity. N-terminal sequence analysis of desaturase freshly isolated from the P-1 fraction without incubation indicated the absence of three residues from the N terminus, but the mobility of this desaturase preparation on SDS-PAGE was identical to the microsomal desaturase, which contains a masked N terminus under similar purification procedures. Addition of concentrated cytosol or the high-salt wash fraction did not enhance the desaturase degradation in the washed microsomes. Extensive degradation of desaturase in the high-salt washed microsomes could be restored by supplementation of the membranes with the lipid and protein components essential for the reconstituted desaturase catalytic activity. Lysosomotrophic agents leupeptin and pepstatin A were ineffective in inhibiting desaturase degradation. The calpain inhibitor, N-acetyl-leucyl-leucyl-methional, or the proteosome inhibitor, Streptomyces metabolite, lactacystin, did not inhibit the degradation of desaturase in the microsomal or the P-1 and P-2 fractions. These results show that the selective degradation of desaturase is likely to be independent of the lysosomal and the proteosome systems. The reconstitution of complete degradation of desaturase in the high-salt-washed microsomes by the components essential for its catalytic activity reflects that the degradation of this enzyme may depend on a specific orientation of desaturase and intramembranous interactions between desaturase and the responsible protease. PMID- 9362068 TI - Functions of FKBP12 and mitochondrial cyclophilin active site residues in vitro and in vivo in Saccharomyces cerevisiae. AB - Cyclophilin and FK506 binding protein (FKBP) accelerate cis-trans peptidyl-prolyl isomerization and bind to and mediate the effects of the immunosuppressants cyclosporin A and FK506. The normal cellular functions of these proteins, however, are unknown. We altered the active sites of FKBP12 and mitochondrial cyclophilin from the yeast Saccharomyces cerevisiae by introducing mutations previously reported to inactivate these enzymes. Surprisingly, most of these mutant enzymes were biologically active in vivo. In accord with previous reports, all of the mutant enzymes had little or no detectable prolyl isomerase activity in the standard peptide substrate-chymotrypsin coupled in vitro assay. However, in a variation of this assay in which the protease is omitted, the mutant enzymes exhibited substantial levels of prolyl isomerase activity (5-20% of wild-type), revealing that these mutations confer sensitivity to protease digestion and that the classic in vitro assay for prolyl isomerase activity may be misleading. In addition, the mutant enzymes exhibited near wild-type activity with two protein substrates, dihydrofolate reductase and ribonuclease T1, whose folding is accelerated by prolyl isomerases. Thus, a number of cyclophilin and FKBP12 "active-site" mutants previously identified are largely active but protease sensitive, in accord with our findings that these mutants display wild-type functions in vivo. One mitochondrial cyclophilin mutant (R73A), and also the wild type human FKBP12 enzyme, catalyze protein folding in vitro but lack biological activity in vivo in yeast. Our findings provide evidence that both prolyl isomerase activity and other structural features are linked to FKBP and cyclophilin in vivo functions and suggest caution in the use of these active-site mutations to study FKBP and cyclophilin functions. PMID- 9362070 TI - End4p/Sla2p interacts with actin-associated proteins for endocytosis in Saccharomyces cerevisiae. AB - end4-1 was isolated as a temperature-sensitive endocytosis mutant. We cloned and sequenced END4 and found that it is identical to SLA2/MOP2. This gene is required for growth at high temperature, viability in the absence of Abp1p, polarization of the cortical actin cytoskeleton, and endocytosis. We used a mutational analysis of END4 to correlate in vivo functions with regions of End4p and we found that two regions of End4p participate in endocytosis but that the talin like domain of End4p is dispensable. The N-terminal domain of End4p is required for growth at high temperature, endocytosis, and actin organization. A central coiled-coil domain of End4p is necessary for formation of a soluble sedimentable complex. Furthermore, this domain has an endocytic function that is redundant with the function(s) of ABP1 and SRV2. The endocytic function of Abp1p depends on its SH3 domain. In addition we have isolated a recessive negative allele of SRV2 that is defective for endocytosis. Combined biochemical, functional, and genetic analysis lead us to propose that End4p may mediate endocytosis through interaction with other actin-associated proteins, perhaps Rvs167p, a protein essential for endocytosis. PMID- 9362071 TI - A novel RING finger protein complex essential for a late step in protein transport to the yeast vacuole. AB - Protein transport to the lysosome-like vacuole in yeast is mediated by multiple pathways, including the biosynthetic routes for vacuolar hydrolases, the endocytic pathway, and autophagy. Among the more than 40 genes required for vacuolar protein sorting (VPS) in Saccharomyces cerevisiae, mutations in the four class C VPS genes result in the most severe vacuolar protein sorting and morphology defects. Herein, we provide complementary genetic and biochemical evidence that the class C VPS gene products (Vps18p, Vps11p, Vps16p, and Vps33p) physically and functionally interact to mediate a late step in protein transport to the vacuole. Chemical cross-linking experiments demonstrated that Vps11p and Vps18p, which both contain RING finger zinc-binding domains, are components of a hetero-oligomeric protein complex that includes Vps16p and the Sec1p homologue Vps33p. The class C Vps protein complex colocalized with vacuolar membranes and a distinct dense membrane fraction. Analysis of cells harboring a temperature conditional vps18 allele (vps18tsf) indicated that Vps18p function is required for the biosynthetic, endocytic, and autophagic protein transport pathways to the vacuole. In addition, vps18tsf cells accumulated multivesicular bodies, autophagosomes, and other membrane compartments that appear to represent blocked transport intermediates. Overproduction of either Vps16p or the vacuolar syntaxin homologue Vam3p suppressed defects associated with vps18tsf mutant cells, indicating that the class C Vps proteins and Vam3p may functionally interact. Thus we propose that the class C Vps proteins are components of a hetero oligomeric protein complex that mediates the delivery of multiple transport intermediates to the vacuole. PMID- 9362074 TI - 'Clearing' cervical spine injuries in polytrauma patients: is it really safe to remove the collar? AB - Polytrauma patients are at increased risk for occult cervical spine injuries. Those unable to provide clinical clues to injury either remain in hard collars until they are able to cooperate with the physical examination or are deemed "clear of cervical injury" if the emergency room screening radiographs are without obvious bony abnormality. Cervical immobilization for a lengthy period of time is not without morbidity. Missed ligamentous injuries can lead to cervical instability, which in turn can result in permanent neurologic sequelae. This article reviews the current methodologies to "clear the cervical spine" and highlights the inadequacies. PMID- 9362072 TI - Rho-stimulated contractility contributes to the fibroblastic phenotype of Ras transformed epithelial cells. AB - Oncogenic transformation of cells alters their morphology, cytoskeletal organization, and adhesive interactions. When the mammary epithelial cell line MCF10A is transformed by activated H-Ras, the cells display a mesenchymal/fibroblastic morphology with decreased cell-cell junctions but increased focal adhesions and stress fibers. We have investigated whether the transformed phenotype is due to Rho activation. The Ras-transformed MCF10A cells have elevated levels of myosin light chain phosphorylation and are more contractile than their normal counterparts, consistent with the activation of Rho. Furthermore, inhibitors of contractility restore a more normal epithelial phenotype to the Ras-transformed MCF10A cells. However, inhibiting Rho by microinjection of C3 exotransferase or dominant negative RhoA only partially restores the normal phenotype, in that it fails to restore normal junctional organization. This result prompted us to examine the effect that inhibiting Rho would have on the junctions of normal MCF10A cells. We have found that inhibiting Rho by C3 microinjection leads to a disruption of E-cadherin cytoskeletal links in adherens junctions and blocks the assembly of new adherens junctions. The introduction of constitutively active Rho into normal MCF10A cells did not mimic the Ras-transformed phenotype. Thus, these results lead us to conclude that some, but not all, characteristics of Ras-transformed epithelial cells are due to activated Rho. Whereas Rho is needed for the assembly of adherens junctions, high levels of activated Rho in Ras-transformed cells contribute to their altered cytoskeletal organization. However, additional events triggered by Ras must also be required for the disruption of adherens junctions and the full development of the transformed epithelial phenotype. PMID- 9362075 TI - Management of odontoid fractures. AB - During the past two decades, various reports on the management of odontoid and axis body fractures have been published and new methods of treatment have been developed. So far, there is no consensus, and management remains controversial. This article reviews the literature and formulates recommendations based on clinical experience. PMID- 9362076 TI - Management of unilateral facet dislocations: a review of the literature. AB - The unilateral dislocated facet is a complex injury and has been described as a locket facet, a perched facet, a jumped facet, and a rotational facet injury. This article reviews past and current recommendations for the diagnosis and treatment of unilateral dislocated facets. PMID- 9362073 TI - Characterization of cell-matrix adhesion requirements for the formation of fascin microspikes. AB - Cell adhesion to thrombospondin-1 (TSP-1) correlates with assembly of cell substratum contact structures that contain fascin microspikes. In this analysis, cell-matrix requirements for assembly of fascin microspikes were examined in detail. In six cell lines, cell spreading on a TSP-1 substratum correlated with expression of fascin protein and formation of fascin microspikes. Microspikes were not formed by H9c2 cells adherent on fibronectin, vitronectin, collagen IV, or platelet factor 4. However, both fascin microspikes and focal contacts were assembled by cells adherent on laminin-1. Using mixed substrata containing different proportions of TSP-1, and fibronectin, fascin microspike formation by H9c2 and C2C12 cells was found to be reduced on substrata containing 25% fibronectin and abolished on substrata containing 75% fibronectin. Adhesion to intermediate mixtures of TSP-1 and fibronectin resulted in coassembly of fascin microspikes and focal contacts, colocalization of fascin with actin stress fiber bundles and altered distributions of beta 1 integrins, cortical alpha-actinin, and tropomyosin. In cells adherent on 50% TSP-1:50% fibronectin, GRGDSP peptide treatment decreased focal contact assembly and altered cytoskeletal organization but did not inhibit microspike assembly. Treatment with chondroitin sulfate A or p-nitrophenol beta-D-xylopyranoside decreased microspike formation and modified cytoskeletal organization but did not inhibit focal contact formation. In polarized migratory and postmitotic C2C12 cells, fascin microspikes and ruffles were localized at leading edges and TSP matrix deposition was also concentrated in this region. Depletion of matrix TSP by heparin treatment correlated with decreased microspike formation and cell motility. Thus, the balance of adhesive receptors ligated at the cell surface during initial cell-matrix attachment serves to regulate the type of substratum adhesion contact assembled and subsequent cytoskeletal organization. A role for fascin microspikes in cell motile behavior is indicated. PMID- 9362078 TI - Thoracolumbar spine injuries. AB - This article reviews some of the anatomic and mechanical aspects of thoracolumbar injuries as they relate to classification systems and stability. In addition, an overview of the initial management including surgical and conservative treatment options is provided. PMID- 9362077 TI - Injuries to the subaxial cervical spine: posterior approach options. AB - In patients with cervical instability as the primary injury, either ligamentous or bony, a posterior approach and stabilization is the most likely definitive treatment. The goals should be to obtain and maintain satisfactory alignment, promote fusion, and allow safe and early mobilization. Many techniques that differ in safety, ease of application, cost, biomechanical strength, and postoperative requirements of immobilization are available. This article reviews different methods of posterior surgical interventions in subaxial cervical spine injuries and discusses the advantages and disadvantages of each. PMID- 9362079 TI - Nonoperative treatment of thoracolumbar fractures. PMID- 9362080 TI - The role of anterior surgery in the treatment of thoracolumbar fractures. AB - Operative treatment of thoracolumbar burst fractures or fracture dislocations is a relatively modern development. Anterior decompression and stabilization play a significant role in the treatment of thoracolumbar burst fractures. This article reviews the clinical indications and describes a one-staged operative technique for anterior instrumentation following anterior decompression. PMID- 9362081 TI - Low-velocity civilian gunshot wounds of the spine. AB - This article describes a retrospective study on patients admitted to a level I trauma center between 1989 and 1993 with low-velocity gunshot wounds to the spine. Medical records and imaging studies were reviewed to determine patient demographics, neurologic deficit, prophylactic antibiotic administration, and rate of infection, spine stability, and principle associated injuries. A total of 37 patients with low-velocity gunshot wounds to the spine were identified and comprised 34% of all spinal injury patients. Neurologic outcome of the low velocity gunshot wound to the spine depended on the level of the injury and the presenting neurologic deficit, as improvement of one or two Frankel grades occurred in only seven patients. Prophylactic antibiotics were given to 20 patients, and one infection occurred and was associated with colon perforation. In the absence of hollow viscus perforation, antibiotic prophylaxis did not appear beneficial. Spinal instability was noted in three patients with cervical injury and one patient with lumbar injury, and neurologic deficit was variable despite the presence of instability. The major associated injury was vascular occlusion or disruption in 8 of 12 (66%) cervical low-velocity gunshot wounds to the spine. PMID- 9362082 TI - An unusual acute compression fracture of the thoracolumbar spine. PMID- 9362083 TI - Incomplete intradural lumbar disk herniation. PMID- 9362084 TI - Lumbar intraradicular disk herniation: report of three cases. PMID- 9362085 TI - Gastroparaspinal fistula: a late postoperative complication of anterior spinal fusion. PMID- 9362086 TI - Chemistry and biology of alkylphenols from Ginkgo biloba L. AB - Ginkgolic acid and related alkylphenols constitute major components of the lipid fraction of the fruit pods of Ginkgo biloba L. In addition, this class of substances is present in Ginkgo leaves which are widely used to prepare extracts for the treatment of peripheral or cerebral circulatory disorders, as well as vascular and Alzheimer type dementia. The present paper reviews the literature on chemical and biological aspects of alkylphenols from Ginkgo with special reference to their allergic and other undesired properties. As these compounds are present in crude leaf extracts, their completest possible removal has therefore to be guaranteed for therapeutically used extracts by the production process. Technically this does not imply any problem and most preparations available on the market fulfil the requirements of the Monograph of the Commission E of the former Federal German Health Authority (Bundesgesundheitsamt, BGA) requesting a maximal concentration of 5 ppm ginkgolic acids. PMID- 9362087 TI - Synthesis and antimicrobial testing of novel oxadiazolylbenzimidazole derivatives. AB - Three novel series of oxadiazolylbenzimidazole derivatives have been prepared, namely 1-[(2-alkylthio or aralkylthio-1,3,4-oxadiazol-5-yl)methyl]-2-alkyl-1 H benzimidazoles 3a-f; 1-[(3-substituted aminomethyl-2-thioxo-2,3-dihydro-1,3,4 oxadiazol-5-yl)methyl ]-2-alkyl-1 H-benzimidazoles 4a-f and 1-[(2-substituted amino-1,3,4-oxidiazol-5-yl)methyl]-2-alkyl-1 H-benzimidazoles 6a-j. The antimicrobial testing of the prepared compounds was performed, some of them showed week activity. PMID- 9362088 TI - Synthesis and antimicrobial screening of some novel thiazoles, dithiazoles and thiazolylpyridines. AB - Several thiazolines 2a-c, and 4-thiazolidinones 3a-c were synthesized through the reaction of the cyanoacetic acid hydrazide derivatives 1a-c with phenacyl bromides or chloroacetic acid, respectively. The dithiazoles 4a, b were obtained from 2a, b through their reaction with sulphur and phenyl isothiocyanate. The dithiazoles 6a, b were prepared from 4a through its reaction with dimethyl sulphate followed by reaction of the produced 2-methylthiothiazolium salt 5 with either malononitrile or ethyl cyanoacetate. The thiazolyl-pyridines 7a, b and 8a, b were obtained from 2a, b through their reaction with arylidene malonitrile and arylidene ethyl cyanoacetate, respectively. The prepared compounds were screened for their antibacterial and antifungal activities in vitro. Some of them showed weak effects. PMID- 9362089 TI - Synthesis of some biologically active agents derived from thieno[2,3-d]pyrimidine derivatives. AB - The key compound 1-amino-8-iminocyclopenta[b]thieno[2,3-d]pyrimidine (5g) was prepared by reaction of 2-amino-3-cyano cyclopenta[b]thiophene (1) with triethyl orthoformate followed by cyclization with hydrazine hydrate in ethanol. Refluxing of 1 with triethyl orthoformate in the presence of acetic anhydride gave an unexpected product 2. while reaction with aromatic amines gave the condensation products 4a-c. Reaction of 5g with formic acid, other formate derivatives, ethoxymethylenemalononitrile and ethyl ethoxymethylenecyanoacetate gave the same product cyclopentathieno-[2,3-d]-1,2,4-triazolo[3,2-f]pyrimidine 6. Compound 7 was prepared by different methods. Treatment of 5g with dicarbonyl compounds gave the triazol derivatives 8-11. Reaction of 5g with phenyl isothiocyanate, carbon disulphide and ethyl chloroformate gave the corresponding derivatives 12-14, respectively. Condensation of 5g with some selected aromatic and heterocyclic aldehydes, acetone, N-acetyl isatin and isatin gave the condensation products 15a e, 16-18, respectively in good yields. Many of the synthesized compounds were tested in vitro for their inhibitory activity against a variety of bacteria such as: Serratia rhodnii, Bacillus cereus, Staphylococcus citreus and Pseudomonas aeruginosa and fungi such as: Aspergillus flavus, Penicillium chrysogenum and Alternaria alternarta. Some compounds showed modest activity. PMID- 9362090 TI - ng-determination of cyclosporine A in cutaneous scales. PMID- 9362091 TI - Stability of mono- and bisbenzyloxime ethers of the acetylcholinesterase reactivator TMB-4. AB - Mono- and bisbenzyloxime ethers of the bispyridinium derivative TMB-4 (UNO, DUO) are potent allosteric modulators of the muscarinic receptor attracting clinical interest in case of organophosphate poisoning. In order to work out the stability of these compounds oximes, different oxime ethers and potential degradation products were synthesized and UV- and NMR-spectroscopically characterized. The process of degradation of all compounds was observed under stress conditions at varying pH-values and different temperatures by means of time-dependent NMR- und UV-measurements. The pyridinium aldoxime turned out to be rather stable, whereas the oxime ether and cyano derivatives convert to the pyridone at high pH-values and high temperature. The mechanism of degradation is discussed. PMID- 9362092 TI - Effect of flavonoids on daunomycin-induced toxicity in cultivated endothelial cells. AB - The cytotoxicity of daunomycin in cultivated endothelial cells was differentially influenced by selected flavonoids. One group (myricetin, flavone, apigenin) enhanced daunomycin toxicity whereas flavonols like quercetin, kaempferol, rutin and morin significantly inhibited this cytotoxicity. Other flavonoids like hesperidin, naringin and catechin did not interact with the daunomycin-induced inhibition of proliferation. There was no correlation between lipophilicity and toxicity of the flavonoids and the observed effects on daunomycin-induced cytotoxity. The protective effect of quercetin and rutin seems to be connected with the antioxidative properties of these flanonols. PMID- 9362093 TI - Antimycobacterial activity of some 2,3-dianilinoquinoxaline derivatives. AB - The antimycobacterial activity of 2,3-dianilinoquinoxaline derivatives was studied and the substances were found to be mostly wide-spectrum antimycobacterial agents. Replacement of one nitrogen atom in the heterocycle for oxygen or sulfur was usually accompanied by loss of activity. The model structure for the study was the wide-spectrum antimycobacterial drug clofazimine. PMID- 9362094 TI - Antiinfective activity of a plant preparation from Geranium sanguineum L. AB - A methanol extract (PC) has been obtained from the Bulgarian medicinal plant Geranium sanguineum L. The antiinfective activity of the plant preparation was studied. The extract inhibited the reproduction of a range of viruses (influenza, herpes simplex, vaccinia, HIV-I) in cell cultures. Its antiinfluenza effect was most pronounced; PC reduced the infectivity of various influenza virus strains in vitro and protected mice in experimental influenza infection. The polyphenol extract inhibited the in vitro growth of Staphylococcus aureus and Candida albicans. PMID- 9362095 TI - From the earliest days of humans' habitation of the earth, we have been forced to adapt to an everchanging and often hostile environment. PMID- 9362097 TI - Advanced medical imaging and treatment of human cystic echinococcosis. PMID- 9362096 TI - Amebiasis: modern diagnostic imaging with pathological and clinical correlation. PMID- 9362098 TI - Radiological diagnosis of giardiasis. PMID- 9362099 TI - Current diagnostic imaging of pulmonary and cerebral paragonimiasis, with pathological correlation. PMID- 9362100 TI - Computed tomography and magnetic resonance imaging of neurocysticercosis. PMID- 9362101 TI - Chronic effects of methylmercury in rats. I. Biochemical aspects. AB - To examine chronic effects of methylmercury (MeHg), male Wistar rats were fed on MeHg-contaminated diet, 0, 1 and 5 ppm Hg, under a restricted feeding schedule of 16 g/rat/day for 6 days a week. Rats were killed at 6-month intervals for examination of Hg accumulation, tissue levels of glutathione, metallothionein and lipid peroxide, as well as anti-oxidative enzyme activities. The survival of the 5 ppm Hg group, 50% of which died by the end of 32nd month of the exposure, was somewhat shorter than control and 1 ppm Hg groups, 50% of which survived for 34 months. Although the rats showed no neurological signs or decreased body weight gain even in 5 ppm Hg-exposed group until the end of the 2nd year, crossing of hind limb was evident after 2.5 years in all three groups. Accordingly, the neurological sign observed here possibly due to aging rather than MeHg toxicity. Tissue Hg levels showed a dose-dependent accumulation except for the kidney, where the highest Hg accumulation was observed among tissues examined. Renal Hg levels in the 1 ppm group showed about 40% of those in the 5 ppm group. Significant effects by MeHg were evident only in the kidney, where glutathione and metallothionein levels increased in both MeHg-exposed groups. However, lipid peroxide levels elevated only in 1 ppm group. Among the antioxidative enzymes examined, the renal glutathione peroxidase was found to be the most labile enzyme against MeHg exposure. Renal dysfunction suggested by increased plasma creatinine levels was also significant in 5 ppm Hg rats at 2 years. Furthermore, anemia which would be caused by reduced erythropoietin production in the kidney was also evident in this group. The present study suggested that the kidney was the most susceptible organ against MeHg toxicity under the present exposure schedule and that the renal dysfunction might at least partly account for the shortened survival in 5 ppm Hg rats. PMID- 9362103 TI - EMG power spectrum and integrated EMG of ankle plantarflexors during stepwise and ramp contractions. AB - The aim of this study was to investigate whether the median frequencies (MF) of the electromyogram (EMG) and the integrated EMG (IEMG) of histochemically differentiated ankle plantarflexors, the gastrocnemius and soleus, were force dependent. Bipolar intramuscular wire electrodes were used to measure EMG of the soleus (SO), medial head of gastrocnemius (GM), and lateral head of gastrocnemius (GL) during ramp (single ongoing contractions) with the force increasing linearly from 0 to 100% of maximum voluntary contraction (MVC) and stepwise (steady force levels) ankle plantarflexion at 10, 20, 30, 40, 60, and 80% MVC. EMG and force were measured simultaneously. Power spectral analysis of these signals was performed to calculate MF on 1024-point by fast Fourier transform (FFT) technique. IEMG value of each muscle was also obtained at the same levels of force. While IEMG of three heads of triceps surae in both stepwise and ramp contractions increased significantly with increasing force, MF values of GL during stepwise contraction increased significantly (20, 40, 60, 80% MVC). These results suggest that the sensitivity of EMG power spectrum might be influenced by the proportion of fast twitch muscle fibers, which histochemically corresponds to type II fibers. PMID- 9362102 TI - Chronic effects of methylmercury in rats. II. Pathological aspects. AB - Chronic effects of methylmercury (MeHg) were examined pathologically in male Wistar rats fed on diet containing 0, 1 or 5 ppm Hg (as MeHg) for two years. Organs including the central nervous tissues were examined histopathologically using hematoxylin and eosin (H & E), Kluver-Barrera (KB), PAS or phenol-congo red stains. The peripheral nerve system tissues were also examined, using H & E and trichrome stains. Furthermore, immunoglobulins of renal specimens were demonstrated by direct immunofluorescence microscopy. Localization of mercury in the paraffin-embedded sections of the nervous tissue, kidney, liver, pancreas, spleen and testis was demonstrable by the photoemulsion histochemical method. In the 5 ppm group, mercury was readily detectable in tissues of the rats exposed for one year, one and half years, two years and two and half years. Mercury was detected in the cells of the brain such as neurons, neuroglial cells, and phagocytes, and also in most organs, particularly in the epithelium of renal tubules, liver cells, myocardium, in the macrophages of pancreas, spleen and testis. In the 1 ppm group, mercury was detectable in the epithelium of renal tubules and liver cells. Fibrosis of the glomeruli was found in the rat group given a high dose of methylmercury with all experimental methods. Granular IgG, IgM and C3 deposits were demonstrated in the glomeruli by direct immunofluorescence microscopy. The etiology of the pathological changes of glomeruli was suspected to be autoimmune glomerulopathy due to inorganic mercury filtration for a long time. It was difficult to determine the clinical signs and symptoms and pathological changes in the nervous system in spite of the deposition of mercury in the brain. PMID- 9362104 TI - Suppression of acute experimental allergic encephalomyelitis in Lewis rats with a mycophenolic acid derivative. AB - Oral administration of ethyl O-[N-(p-carboxyphenyl-carbamoyl]-mycophenolate (CAM), a derivative of mycophenolic acid (MPA) and an inosine monophosphate dehydrogenase inhibitor, dose-dependently suppressed acute experimental allergic encephalomyelitis in Lewis rats without exerting any serious adverse effects. A daily dose of 50 mg/kg of CAM almost completely abolished both the clinical disease and the inflammation in the CNS. In the CAM-treated rats, a weight loss and fluctuations of peripheral lymphocyte subsets were minimized. The CAM treatment was effective when started at the time of sensitization but ineffective when deferred till day 10. Furthermore, CAM reduced the percentage of CD4+CD45RC- cells in the peripheral blood. The only detectable adverse effect was moderate anemia but it was rapidly improved after withdrawal of the drug. This drug could be a useful adjunct for the long-term immunosuppressive therapy for inflammatory diseases of the CNS. PMID- 9362105 TI - Effect of theophylline on hypoxic pulmonary vasoconstriction in awake rats. AB - Whether or not theophylline inhibits hypoxic pulmonary vasoconstriction in vivo still remains uncertain. We therefore studied the effect of theophylline on hypoxic pulmonary vasoconstriction in awake rats. Two days before hemodynamic measurement, indwelling catheters were placed. Animals were divided into three groups; Group-H (20 mg/kg of theophylline), Group-L (8 mg/kg of theophylline), Group-S (saline). At the day of hemodynamic measurement, animals breathed 21% and 10% O2 gas. [{Pulmonary vascular resistance (PVR) during 10% O2-PVR during 21% O2}/PVR during 21% O2] x 100 was termed as hypoxic pulmonary vasoconstriction (HPV). The first HPV measurement was followed without drug administration and then the second HPV measurement was performed with theophylline or saline infusion. Post-theophylline HPV was divided by pre-theophylline HPV to normalize individual variation. Ratio of post-theophylline HPV to pre-theophylline HPV was 0.49 +/- 0.10, 0.77 +/- 0.23, 1.06 +/- 0.33 in Group -H, -L, -S, respectively (means +/- S.E.M). Ratio of post-theophylline HPV to pre-theophylline HPV was significantly less in Group-H than in Group-S. This result suggests that theophylline used in the present study (18.6-26.9 micrograms/ml) attenuates hypoxic pulmonary vasoconstriction in the unanesthetized rat. PMID- 9362106 TI - Expression of CD34 in glomus tumors. AB - Immunohistochemical studies were performed in order to characterize glomus tumors. In all cases the glomus tumor cells stained positively for smooth muscle actin. In half of six cases, the glomus tumor cells weakly expressed desmin. They were not reactive with Ulex europaeus agglutinin-I and anti-Factor VIII-related antigen, whereas the only endothelial cells were reactive with them. The tumor cells as well as vascular endothelial cells amongst the tumor cells expressed CD34 in five of the cases. PMID- 9362107 TI - Danazol induced thrombocytopenia. AB - A 34-year-old woman with a left ovarian cyst (clinically diagnosed as endometrial cyst) was treated with 400 mg of danazol per day. On the next day, after a total dose of only 600 mg of danazol, gingival bleeding and purpura occurred. Her laboratory findings were as follows: platelet count 1000/ mm3 hematocrit 39%, WBC 7300/mm3 and RBC 466 x 10(4)/mm3. Immune thrombocytopenic purpura (ITP) was diagnosed, and she was treated with 40 mg of methylprednisolone per day for 19 days. Her platelet count increased to 130,000/ mm3. Her left ovarian cyst was extirpated surgically, and the histological diagnosis was endometrial cyst. Danazol at 400 mg per day was therefore again administered. On the next day, she complained of gingival bleeding and purpura again, and her platelet count was 5000/mm3. We diagnosed this case as danazol induced thrombocytopenia. PMID- 9362108 TI - Systemic lupus erythematosus in a patient whose younger sister had allergic granulomatous angitis. AB - A 37-year-old woman visited to our hospital due to general edema. The patient was diagnosed as having systemic lupus erythematosus (SLE) associated with chronic glomerulonephritis, which developed into chronic renal failure and was treated with regular hemodialysis. The patient's younger sister had been followed in our outpatient's clinic because of allergic granulomatous angitis (AGA). The sibling's common histocompatibility leukocyte antigens (HLA) were A24(9), B52(5), and DR2. PMID- 9362109 TI - Symptomatic aortic regurgitation after Blalock-Taussig shunt in tetralogy of Fallot with bicuspid aortic valve. AB - We report here a case of a premature baby with tetralogy of Fallot and bicuspid aortic valve. After the successful completion of the Blalock-Taussig (BT) shunt, severe aortic valve regurgitation (AR) appeared, although it was trivial preoperatively. Severe postoperative heart failure was induced by progression of the AR. Postoperative echocardiography revealed that the progression of the AR was provoked by appearance of prolapse of the cusp as the result of rapid increase of blood flow through the aortic valve after the BT shunt. We propose that, in planning the BT shunt for patients with tetralogy of Fallot, preoperative examinations for a possible bicuspid aortic valve should be done and postoperative precaution considering possible appearances of severe AR and congestive heart failure will be necessary. PMID- 9362110 TI - A case of leiomyosarcoma of the sphenoid sinus. AB - A 43-year-old man with a primary leiomyosarcoma of the left sphenoid sinus is presented. To our knowledge, this is an unusual case of leiomyosarcoma, which has never been reported in the literature. Accurate and safe diagnosis was obtained by an endonasal endoscopic approach with minimal tissue invasion. PMID- 9362111 TI - Purification and properties of two isozymes of gamma-glutamyltranspeptidase from Bacillus subtilis TAM-4. AB - Two isozymes of gamma-glutamyltranspeptidase, GGT-A and GGT-B, were purified to electrophoretic homogeneity from a culture broth of Bacillus subtilis TAM-4, which produces poly(gamma-glutamic acid) (PGA) de novo. GGT-A was composed of three subunits with molecular weights of 23,000 (I), 39,000 (II), and 40,000 (III). GGT-B was composed of two subunits with molecular weight of 22,000 (I) and 39,000 (II). The N-terminal amino acid sequences of GGT-A subunit I and GGT-B subunit I were very similar. GGT-A subunit II and GGT-B subunit II had an identical N-terminal amino acid sequence. That of GGT-A subunit III showed no similarity to the other subunits. Both GGTs had similar enzymatic properties (optimum pH and temperature: pH 8.8 and 55 degrees C) but showed a significantly different thermal stability at 55 degrees C. Both GGT-A and -B used D-gamma glutamyl-p-nitroanilide as well as the L-isomer as the gamma-glutamyl donor and used various amino acids and peptides as the acceptor. It was also found that the PGA produced by the strain was hydrolyzed to glutamic acid by its own GGTs. PMID- 9362112 TI - Interaction of mercury with human and bovine milk proteins. AB - The interaction of inorganic mercury with human and bovine milk proteins was studied. Gel filtration chromatography of skimmed milk and whey incubated with mercury showed that, in human milk, mercury was mainly bound to caseins, while a low proportion was bound to albumin. In bovine milk, mercury was associated with two protein fractions, caseins and beta-lactoglobulin. Furthermore, it was shown by electrophoresis that mercury induced the formation of dimers of beta lactoglobulin. Thus, in both human and bovine milk, mercury possessed greater ability to interact with milk proteins than to the low-molecular-weight substances. However, the pattern of mercury distribution was different between the milk of these two species. PMID- 9362113 TI - Generation of reactive oxygen species by raphidophycean phytoplankton. AB - Chattonella marina, a raphidophycean flagellate, is one of the most toxic red tide phytoplankton and causes severe damage to fish farming. Recent studies demonstrated that Chattonella sp. generates superoxide (O2-), hydrogen peroxide (H2O2), and hydroxyl radicals (.OH), which may be responsible for the toxicity of C. marina. In this study, we found the other raphidophycean flagellates such as Heterosigma akashiwo, Olisthodiscus luteus, and Fibrocapsa japonica also produce O2- and H2O2 under normal growth condition. Among the flagellate species tested, Chattonella has the highest rates of production of O2- and H2O2 as compared on the basis of cell number. This seems to be partly due to differences in their cell sizes, since Chattonella is larger than other flagellate species. The generation of O2- by these flagellate species was also confirmed by a chemiluminescence assay by using 2-methyl-6-(p-methoxyphenyl)-3,7 dihydroimidazo[1,2-a]pyrazin++ +-3-one (MCLA). All these raphidophycean flagellates inhibited the proliferation of a marine bacterium, Vibrio alginolyticus, in a flagellates/bacteria co-culture system, and their toxic effects were suppressed by the addition of superoxide dismutase (SOD) or catalase. Our results suggest that the generation of reactive oxygen species is a common feature of raphidophycean flagellates. PMID- 9362114 TI - Production of recombinant Der fI with the native IgE-binding activity using a baculovirus expression system. AB - Der fI is a cysteine protease contained in feces of mites and is one of major mite allergens. Recombinant Der fI (reDer fI) that is produced using a baculovirus expression system contains pro-sequences of different lengths. Most of these can be removed by acid treatment. However, IgE-binding activity of acid treated reDer fI is lower than that of native Der fI at high protein concentrations, and N-terminal amino acids of acid-treated reDer fI are not uniform. Now, a method for processing of the pro-sequence has been developed by producing reDer fI E(-1)K with baculovirus expression system in which the carboxy terminal amino acid of the pro-sequence (glutamate) was replaced by lysine using site directed mutagenesis. No difference in the amount of production was observed upon introducing the mutation into the pro-sequence. Addition of lysylendopeptidase into the culture medium led to processing of the pro-sequence of reDer fI E(-1)K and proceeded the degradation of the other proteins in the medium. Lysylendopeptidase-treated reDer fI E(-1)K was easily purified with an anion exchange column, resulting in 20% increase of the yield. Lysylendopeptidase treated reDer fI E(-1)K obtained through these processes was compared with the native Der fI. Although some differences were found in protease activity and reactivity with lectins, their N-terminal amino acid and the IgE-binding activity were the same as those of the native one, indicating its usefulness for diagnostic purpose. PMID- 9362115 TI - Effects of dietary pyrazinamide on the metabolism of tryptophan to niacin in streptozotocin-diabetic rats. AB - We investigated the effects of feeding with a diet containing pyrazinamide (PYR) on the metabolism of L-tryptophan (Trp) to nicotinamide in streptozotocin (STZ) diabetic rats and whether the diabetic action of STZ is prevented by feeding with the PYR diet, which is known as an inhibitor of aminocarboxymuconate-semialdehyde decarboxylase and poly(ADP)ribose synthetase and therefore, significantly increases the formation of nicotinamide from Trp in normal rats. As was expected, feeding with the PYR diet to the STZ-injected rats caused a significantly increased excretion of nicotinamide and its metabolites like that in normal rats. The body weight increased in the STZ-injected rats fed with the PYR diet, while it was lost in the STZ-injected rats fed with the non-PYR diet. However, the blood glucose level and the urinary excretion of glucose were not improved even when the rats were fed with the PYR diet. Therefore, it was suggested that chronically increasing the formation of nicotinamide from Trp could not completely prevent the STZ-diabetic action. PMID- 9362116 TI - Isolation and some properties of sorbitol oxidase from Streptomyces sp. H-7775. AB - A sorbitol oxidase (SOX) was found in the cell-free extract of a strain isolated from soil. The strain was classified and designated as Streptomyces sp. H-7775. SOX is constitutively expressed in the cell. The molecular weight of SOX that purified from the cell-free extract was 45,000. The optimum pH and the K(m) for sorbitol were 6.5-7.5 and 0.26 mM, respectively. The prosthetic group was a covalently bound FAD. SOX catalyzed oxidation of D-sorbitol to glucose and hydrogen peroxide without any requirements of exogenous cofactors. SOX did not react with glucose, a reaction product of D-sorbitol. This feature is useful in its application for diagnosis. PMID- 9362117 TI - Cloning of genes of the aminopeptidase T family from Thermus thermophilus HB8 and Bacillus stearothermophilus NCIB8924: apparent similarity to the leucyl aminopeptidase family. AB - To obtain genes with sequence similarity to aminopeptidase T (AP-T) of Thermus aquaticus YT-1, we cloned the genes encoding aminopeptidase Th (AP-Th) from Thermus thermophilus HB8 and aminopeptidase II (APII) from Bacillus stearothermophilus NCIB8924. The AP-Th gene encoded a polypeptide of 408 amino acid residues and the deduced molecular weight of this subunit was 45,015. The APII gene encoded a polypeptide of 413 amino acid residues with a deduced molecular weight of 46,207. The extent of amino acid sequence similarity between AP-Th and AP-T was 86%, and that between APII and AP-T was 43%. The substrate specificities of these expressed enzymes were similar, and each efficiently hydrolyzed leucyl- or phenyl-peptide substrates. Since the deduced amino acid sequence of these enzymes show no similarity to other known aminopeptidases, they appear to comprise an independent family of peptidases, designated the AP-T family. However, a conserved region within the enzymes of the AP-T family shows similarity to the active site signature of the leucyl aminopeptidase family, suggesting that these enzymes may belong to the leucyl aminopeptidase superfamily. PMID- 9362118 TI - Increase in swimming endurance capacity of mice by capsaicin-induced adrenal catecholamine secretion. AB - Increase in endurance swimming capacity caused by capsaicin (CAP), a pungent component of red pepper, -induced increase of fat metabolism in mice was investigated using an adjustable-current water pool. The mice administered CAP via a stomach tube, showed longer swimming time until exhaustion than the control group of mice, in a dose-dependent manner. The maximal effect was observed at a dose of 10 mg/kg while more than 15 mg/kg had no effect. The increase of endurance was observed only when CAP was administered two hours before swimming. After the administration of CAP, the serum glucose concentration rapidly increased and then decreased within 60 min, while the concentration of serum-free fatty acids gradually increased through 3 hours. The residual glycogen concentration of the gastrocnemius muscle after 30 min of swimming was significantly higher in the CAP-administered mice than in control mice, suggesting that use of the serum free fatty acids spared muscle glycogen consumption. The serum adrenaline concentration significantly increased with twin peaks at 30 min and two hours after administration of CAP. An experiment using adrenalectomized mice was done to confirm that the effect of CAP is due to increased energy metabolism through the secretion of adrenaline from the adrenal gland. The swimming endurance capacity of the adrenalectomized mice was not increased by CAP administration, although adrenaline injection induced a 58% increase in the endurance time. These results suggest that the increase of swimming endurance induced by CAP in mice is caused by an increase in fatty acid utilization due to CAP-induced adrenal catecholamine secretion. PMID- 9362119 TI - A protein factor is essential for in situ reactivation of glycerol-inactivated adenosylcobalamin-dependent diol dehydratase. AB - The adenosylcobalamin-dependent diol dehydratase of Klebsiella oxytoca undergoes suicidal inactivation by glycerol during catalysis involving irreversible dissociation of the Co-C bond of the coenzyme. The glycerol-inactivated holoenzyme in permeabilized cells (in situ) of E. coli harboring a plasmid containing the diol dehydratase genes and their flanking regions was rapidly reactivated in the presence of free AdoCbl, ATP, and Mg2+. beta,gamma-Methylene ATP was not able to replace ATP. Inactive complexes of the enzyme with aqCbl, CN Cbl, and PeCbl were activated in situ in the presence of AdoCbl, ATP, and Mg2+, but the complex with AdePeCbl was not. These results suggest that the inactivated holoenzyme is reactivated in situ in the presence of ATP and Mg2+ by exchange of the inactivated coenzyme lacking the adenine moiety for free intact AdoCbl. The in situ reactivation was also observed when an analog lacking the alpha-ribose moiety of the nucleotide loop was used as coenzyme. The results with a recombinant E. coli strains carrying a deletion mutant plasmid demonstrate that certain protein(s) encoded by the 3'-flanking region of the diol dehydratase genes are essential for the in situ reactivation of inactivated diol dehydratase. PMID- 9362120 TI - Oxidative stability of liposomes prepared from soybean PC, chicken egg PC, and salmon egg PC. AB - The oxidative stability of phosphatidylcholines (PCs) from soybean, chicken egg, and salmon egg in liposomes was compared with that in aqueous micelles. When each PC was oxidized in aqueous micelles, salmon egg PC was the most oxidatively stable, followed by chicken egg PC and soybean PC, however, no significant difference in the oxidative stability was apparent between chicken egg PC and salmon egg PC in liposomes. The main molecular species of soybean PC was 1,2 dilinoleoyl-PC, while most of the PUFAs in chicken egg PC and salmon egg PC were not esterified at the sn-1 position but at the sn-2 position. Therefore, it is suggested that the oxidative stability of PC liposomes would be strongly influenced by the positional distribution of PUFAs in the PC molecule. Further studies on the oxidation of PC liposomes showed that chicken egg albumin and soybean protein protected PC bilayers against attack by free radicals generated in the aqueous phase. PMID- 9362121 TI - Purification and characterization of konjac glucomannan degrading enzyme from anaerobic human intestinal bacterium, Clostridium butyricum-Clostridium beijerinckii group. AB - Konjac glucomannan degrading enzyme was purified to homogeneity from the culture broth of an anaerobic human intestinal bacterium, Clostridium butyricum Clostridium beijerinckii group. The enzyme was composed of a single polypeptide chain with a molecular weight of 50,000-53,000. The enzyme was an endo-beta mannanase that acted specifically on the polysaccharides such as konjac glucomannan and coffee mannan, producing exclusively their smaller oligosaccharides and the monosaccharides. The optimal pH of the enzyme for the hydrolysis of konjac glucomannan was around 7-8 and the enzyme was stable in rather alkaline pH range of 8-10. The enzyme reaction was activated by the addition of CaCl2 and dithiothreitol. It was suggested that the enzyme might contribute to the decomposition of konjac glucomannan in human digestive tract. PMID- 9362122 TI - Molecular cloning of a new type of cDNA for pheromone biosynthesis activating neuropeptide in the silkworm, Bombyx mori. AB - A neuropeptide named pheromone biosynthesis activating neuropeptide (PBAN) stimulates the pheromone production of lepidopteran insects. We have identified a different type of cDNA for PBAN, which shows two amino acid replacements in the region of the PBAN sequence previously reported. Single strand conformation polymorphism (SSCP) analysis revealed that the two types of cDNA originated from two allelic variants of the gene for PBAN. PMID- 9362123 TI - Prolyl endopeptidase inhibitors derived from actinomycetes. AB - Four prolyl endopeptidase inhibitors isolated from actinomycetes, named propeptin, SNA-8073-B, staurosporine, and enduracidin were classified into 3 groups on the basis of their inhibition potency against prolyl endopeptidase from a bacterium (Flavobacterium) and a mammal (human placenta). Staurosporine inhibited the enzyme from Flavobacterium more strongly than that from human placenta. Enduracidin inhibited the enzyme from human placenta more strongly than that from Flavobacterium. Propeptin and SNA-8073-B, both new compounds, inhibited the enzymes from both origins to the same extent. PMID- 9362124 TI - Sequence analysis of functional regions of homoserine dehydrogenase genes from L lysine and L-threonine-producing mutants of Brevibacterium lactofermentum. AB - The homoserine dehydrogenase (HD) genes from Brevibacterium lactofermentum lysine and threonine-producing mutants were cloned, using the polymerase chain reaction, and sequenced. We found the amino acid substitutions, Val104Ile in the lysine-producing mutants in which HD may cause leaky mutation and Ser393Phe in the threonine-producing mutant with feedback-insensitive HD. PMID- 9362125 TI - Construction of T-tailed vectors derived from a pUC plasmid: a rapid system for direct cloning of unmodified PCR products. AB - We constructed two new T-vectors called pUCTA119 and pUCTA18, derived from pUC18. The vectors were designed to produce single thymidine (T)-overhangs when digested with a restriction enzyme Eam11051. The use of the vectors provides a very rapid system for direct TA cloning and subsequent sequencing of unmodified PCR products since Taq DNA polymerase preferentially adds an adenosine (A) residue to the 3' end of the products under standard PCR conditions. PMID- 9362126 TI - Carquinostatin B, a new neuronal cell-protecting substance produced by Streptomyces exfoliatus. AB - Brain ischemia injury is elicited by the excitotoxicity of L-glutamate. Carquinostatin B was isolated from Streptomyces exfoliatus 2419-SVT2 as a potent neuroprotective substance which protests neuronal hybridoma N18-RE-105 cells from L-glutamate toxicity. The structure of carquinostatin B was established principally by NMR studies to be a carbazole derivative with an ortho quinone function. PMID- 9362127 TI - Fluorometric measurement of yessotoxins in shellfish by high-pressure liquid chromatography. AB - A rapid HPLC method with fluorescence detection of yessotoxin (YTX) and its two analogs (45-OHYTX and norYTX) in mussels and scallops is presented. A dienophile reagent, DMEQ-TAD, was used for fluorescence labeling. YTX was measured in the range 1-100 ng. The method confirmed the occurrence of YTX and 45-OHYTX for the first time in mussels from Chile and New Zealand. PMID- 9362128 TI - Identification of the absolute configuration of pectenotoxin-6, a polyether macrolide compound, by NMR spectroscopic method using a chiral anisotropic reagent, phenylglycine methyl ester. AB - The absolute configuration of pectenotoxin-6 (4, PTX6), found in association with diarrhetic shellfish poisoning, was identified by NMR spectroscopy using a chiral anisotropic reagent, phenylglycine methyl ester (PGME), which was condensed with a carboxyl group of 4. PMID- 9362129 TI - Identification of the minimum segment essential for the H gamma II-specific function of staphylococcal gamma-hemolysin. AB - Staphylococcal gamma-hemolysin consists of H gamma I (or LukF) of 34 kDa and H gamma II of 32 kDa, which cooperatively lyse human erythrocytes. Our previous data showed that the N-terminal 57-residue segment of H gamma II is the essential region for the H gamma II function [H. Nariya and Y. Kamio, Biosci. Biotech. Biochem., 59, 1603-1604 (1995)]. To identify the minimum amino acid residues in the 57-residue segment responsible for the specific hemolytic activity, a series of mutant genes were constructed and expressed in Escherichia coli. The mutant proteins were purified and assayed for their hemolytic activity. The results indicate that the 5-residue segment (K23R24L25A26I27) of H gamma II is the minimum region essential for the H gamma II function. PMID- 9362131 TI - Thread occlusion but not electrocoagulation of the middle cerebral artery causes hypothalamic damage with subsequent hyperthermia. AB - Moderate changes in body temperature can influence the outcome of cerebral ischemic insults and the effect of drugs. Body temperature was measured continuously for 24 hours in rats subjected to permanent occlusion of the middle cerebral artery (MCA) by either coagulation or thread insertion, and the results correlated with the histology of the hypothalamus. The body temperature did not change after MCA occlusion by coagulation and the hypothalamus was intact in all rats. In contrast, the body temperature rapidly increased from about 38 degrees C to more than 39.5 degrees C after MCA occlusion using intraluminal thread, and hyperthermia continued for at least 6 hours in all rats. Histological evaluation revealed neuronal damage in the preoptic area of the hypothalamus in all rats undergoing thread occlusion. Long duration hyperthermia must be prevented after permanent MCA occlusion when the intraluminal thread occlusion model is used in chronic experiments. PMID- 9362130 TI - A beta-glucosidase gene downstream of the cellulose synthase operon in cellulose producing Acetobacter. AB - An open reading frame was found 214 bp downstream of the cellulose synthase operon of Acetobacter. The encoded amino acid sequence was found to be similar to some beta-glucosidases (G3ases). We detected G3ase activity in the culture medium and analysis of the N-terminal amino acid sequence showed that this gene encodes the enzyme. Therefore, it is possible that this region is a gene cluster for cellulose synthesis. PMID- 9362132 TI - Effect of adenoviral-mediated thymidine kinase transduction and ganciclovir therapy on tumor-associated endothelial cells. AB - Transduction of the herpes simplex virus thymidine kinase (HSV-tk) into vascular endothelial cells using a replication-defective adenoviral vector (Ad.CMV-tk) to confer sensitivity to ganciclovir (GCV) was investigated. The cytotoxic sensitivity of bovine aortic endothelial cells (BAEC) to GCV following Ad.CMV-tk transduction at multiplicity of infection of 100 was ten-fold that of 9L glioma cells in vitro. Deoxyribonucleic acid fragmentation was detected in these BAEC. A co-culture experiment using BAEC transduced with Ad.CMV-tk (BAEC-tk) and 9L cells expressing beta-galactosidase (9L-Lac Z) showed about 70% tumoricidal effect under the conditions of one BAEC-tk cell in 10 9L-Lac Z cells. Tumor-bearing Fisher 344 rats, an experimental brain tumor model, received Ad.CMV-tk intratumorally at 7 days after tumor implantation, and were subsequently treated with intraperitoneal GCV (100 mg/kg). Histological examination found the vascular endothelial cells adjacent to 9L glioma tissue revealed apoptosis. These results suggest that vascular endothelial cells are an attractive target for adenoviral mediated HSV-tk gene therapy. PMID- 9362133 TI - Antitumor activity of recombinant human tumor necrosis factor-alpha (rH-TNF alpha) and liposome-entrapped rH-TNF alpha. AB - The antitumor activities of recombinant human tumor necrosis factor-alpha (rH-TNF alpha) and liposome-entrapped rH-TNF alpha were evaluated in various glioma cell lines and a rat brain T9 gliosarcoma model. rH-TNF alpha had a direct cytotoxic activity against various glioma cell lines in vitro, and indirect cytotoxic activity against gliosarcoma (T9) in vivo. Liposome-entrapped rH-TNF alpha had increased direct cytotoxic activity in vitro, and against experimentally induced brain tumors in vivo. The effects in vivo were probably due to vascular damage of the tumor vessels as shown by histological examination and activation of cytotoxic macrophages as shown in vitro. These results indicate that the general or local administration of liposome-entrapped rH-TNF alpha may become a useful adjunct treatment for malignant brain tumor. PMID- 9362134 TI - Aneurysm of the anterior communicating artery associated with accessory middle cerebral artery--case report. AB - A 63-year-old female presented with an anterior cerebral artery aneurysm associated with accessory middle cerebral artery. The aneurysm was located on one of the duplicate anterior communicating arteries, and the accessory middle cerebral artery originated from the anterior cerebral artery adjacent to this aneurysm. The recurrent artery of Heubner was not recognized. The accessory middle cerebral artery may have been involved in the genesis of the aneurysm by changing the hemodynamics in the anterior cerebral arteries. PMID- 9362135 TI - Coexistence of ganglioglioma and cortical dysplasia in a patient with intractable epilepsy--case report. AB - An 8-year-old girl presented with coexistence of ganglioglioma and cortical dysplasia manifesting as intractable epilepsy. Preoperative computed tomography demonstrated a small calcified lesion in the left frontal lobe which was not diagnosed as ganglioglioma. Magnetic resonance imaging also failed to demonstrate positive evidence of ganglioglioma or cortical dysplasia. A calcified tumor and the surrounding epileptogenic areas were resected under electrocorticography (ECoG) guidance. Histological examination revealed coexistence of ganglioglioma and cortical dysplasia. The patient became seizure-free after surgery. Resection of the ganglioglioma together with the adjacent epileptogenic area under intraoperative ECoG guidance is important to achieve a successful surgical result in patients with ganglioglioma. PMID- 9362136 TI - Leptomeningeal melanoma associated with straight sinus thrombosis--case report. AB - A 36-year-old female was admitted with leptomeningeal melanoma associated with straight sinus thrombosis manifesting as headache and vomiting. Computed tomography and magnetic resonance imaging showed the subarachnoid space was diffusely enhanced. Her consciousness rapidly deteriorated to a coma. Angiography demonstrated straight sinus thrombosis. Thrombolysis by superselective catheterization and infusion of urokinase was successfully performed. She recovered consciousness, but developed paraparesis 2 weeks later. Malignant melanoma with meningeal dissemination was diagnosed by an open biopsy of the lumbar lesion. Angiitis induced by the infiltration of tumor cells and activation of the blood coagulation cascade was probably the causative mechanism of the sinus thrombosis. PMID- 9362137 TI - Cerebellopontine angle ependymoma with internal auditory canal enlargement and pineal extension--case report. AB - A 38-year-old male presented with a posterior fossa ependymoma with unusual extension from the cerebellopontine angle to the pineal region. Magnetic resonance imaging clearly demonstrated that these two components were continuous through the right ambient cistern. Computed tomography using a bone algorithm revealed enlargement of the right internal auditory canal. This case suggests that ependymoma can extend anywhere within the subarachnoid space along the path of least resistance. PMID- 9362138 TI - Giant cell granulomatous hypophysitis manifesting as an intrasellar mass with unilateral ophthalmoplegia--case report. AB - A 62-year-old female presented with giant cell granulomatous hypophysitis manifesting as subacute unilateral ophthalmoplegia. Neuroimaging revealed a mass lesion expanding in the pituitary fossa. The mass was totally removed through the transsphenoidal approach. The histological diagnosis was giant cell granuloma. The oculomotor nerve paresis resolved completely 10 days after the operation. Giant cell granulomatous hypophysitis is symptomatically and radiologically indistinguishable from non-functioning pituitary adenoma, but is less likely to cause visual disturbance than pituitary adenoma. Giant cell granulomatous hypophysitis should be considered in the differential diagnosis of sellar and suprasellar lesions, particularly if oculomotor nerve paresis is observed without impaired visual field or acuity. PMID- 9362139 TI - Hemifacial spasm resulting from facial nerve compression near the internal acoustic meatus--case report. AB - A 61-year-old female presented with a rare case of hemifacial spasm (HFS) resulting from facial nerve compression near the internal acoustic meatus. She underwent a first surgery for microvascular decompression at the root entry zone of the facial nerve, but this did not achieve resolution of the HFS. During the second surgery, the meatal loop of the anterior inferior cerebellar artery (AICA) was found to be the offending artery near the internal acoustic meatus. When the AICA was dissected and separated from the facial nerve, abnormal muscle responses of the mentalis muscle due to electrical stimulation of the zygomatic branch of the facial nerve were abolished. Following surgery the patient was completely free of the HFS. PMID- 9362140 TI - Probable brain abscess presenting as a high uptake lesion on thallium-201 single photon emission computed tomography--case report. AB - A 61-year-old male presented with a brain abscess manifesting as high fever and generalized convulsion attacks. Magnetic resonance (MR) imaging disclosed a ring like enhanced lesion in the parietal lobe. Thallium-201 single photon emission computed tomography (201Tl SPECT) images demonstrated a high uptake lesion with a 201Tl uptake index on the early image of 2.21, which suggested malignant disease. The washout ratio was 0.73. His symptoms and the ring-like enhanced lesion on MR images disappeared after 2 months of antibiotic treatment. The final diagnosis was brain abscess, despite the 201Tl SPECT findings. 201Tl SPECT washout ratio may be a better indicator of brain abscess than uptake index. PMID- 9362141 TI - Craniopagus twins. PMID- 9362142 TI - Physical fitness as a function of psychological and situational factors. AB - The association between personality variables suggested by Rotter's social learning theory and indices of physical fitness was examined in a sample of U.S. college students. As predicted, both higher value placed on physical fitness and greater internal locus of control were related to selected indicators of physical fitness. In addition, gender of administrator affected performance on certain measures of physical fitness. The results suggest the need for longitudinal studies to evaluate the role of physical activity in mediating the relationship between personality variables and physical fitness. PMID- 9362143 TI - The relationships among sex role orientation, egalitarianism, attitudes toward sexuality, and attitudes toward violence against women. AB - Relationships among U.S. college students' (N = 618) attitudes toward rape myths and their sex role orientation, affective responses to sexuality, sex role egalitarianism, and attitudes toward violence against women were investigated. Results indicated that men were more tolerant of rape, more likely to attribute blame for rape to the victim, and less negative in their views of rapists than women were. In addition, for men, but not for women, masculinity and femininity were predictive of rape attitudes and attributions of blame to rape victims. Positive attitudes toward sexuality were predictive of intolerance of rape for the total sample and for men, but not for women, and were predictive of perceptions of women as innocent victims of rape for both the total sample and the sexes separately. Attitudes toward pornography were unrelated to attitudes toward rape. Acceptance of violence against women and a lack of sexual egalitarianism were predictive of acceptance of rape myths. Androgynous, masculine, and feminine individuals were less tolerant of rape than undifferentiated persons were. PMID- 9362144 TI - Parental training for incarcerated fathers: effects on attitudes, self-esteem, and children's self-perceptions. AB - The effects of parent education programs on the parenting attitudes and abilities of 30 U.S. male inmates and on the self-perceptions of their children (aged 8-17 years) were examined. Inmates were pre- and post-tested with the Adult-Adolescent Parenting Inventory and the Index of Self-Esteem. The children were administered the Self-Perception Profile for Children or the Self-Perception Profile for Adolescents. Participants in the experimental group completed a 6-week program including parental training and behavior-management training. The control group's 6-week program consisted of viewing family-related videotapes, answering questions, and discussing the contents of the videotapes. Parent education improved the attitudes of inmates toward appropriate parenting but did not significantly change their children's self-perceptions. PMID- 9362145 TI - Social support, reciprocity, and well-being. AB - Systematic random-sampling procedures were used to gather a sample of 191 community residents in Kaohsiung city, Taiwan, and survey them regarding (a) amount of social support given and received; (b) perceived reciprocity of support in relationships with family members, friends, and colleagues; (c) negative affect; and (d) psychological symptoms. Extraversion and social desirability were also measured. Both receiving and giving support were related to negative affect after controlling for the effects of extraversion and social desirability. These two personality factors also substantially masked the negative impact of support on psychological symptoms. Reciprocity of support within the family domain was related to well-being. Individual differences in support exchanges were noted, and women received more support than men. PMID- 9362146 TI - Hindi translation of the Gray-Wilson Personality Questionnaire: a cross-cultural replication of sex differences. AB - The Gray-Wilson Personality Questionnaire (GWPQ) was translated into Hindi and administered to 246 male and 191 female university students. It measures six animal-learning paradigms corresponding to Gray's (1987) three-emotion systems model of personality. Sex differences previously reported from the United Kingdom and Japan were replicated: Women scored significantly higher on the Active Avoidance and Flight subscales, men on the Approach subscale. In the Indian sample, women scored higher than men on the Extinction subscale; this difference, although in the same direction, was not significant in the United Kingdom and Japan. In India, as in Japan and the United Kingdom, women were relatively punishment sensitive, and men were relatively reward sensitive. Consistent with Gray's model, scores on Fight and Flight subscales were positively correlated, as were Passive Avoidance and Extinction subscale scores; however, contrary to the model were the negative correlation between subscale scores for Approach and Active Avoidance and the positive correlation between subscale scores for Approach and Passive Avoidance, also observed previously in the United Kingdom and Japan. PMID- 9362147 TI - Self-perceptions of depressive and nondepressive men in Pakistan. PMID- 9362148 TI - Cigarettes, sex, and lung adenocarcinoma. PMID- 9362150 TI - "Outing" peer review: medical editors scrutinize the value of secrecy. PMID- 9362149 TI - Using 3'-azido-2',3'-dideoxythymidine (AZT) to prevent perinatal human immunodeficiency virus transmission and risk of transplacental carcinogenesis. PMID- 9362151 TI - International group releases first set of global dietary recommendations. PMID- 9362152 TI - Asian Americans and cancer: discarding the myth of the "model minority". PMID- 9362153 TI - European data shows wide variations in cancer survival. PMID- 9362154 TI - Neuropeptide's function stimulates avid scientific interest. PMID- 9362155 TI - Cigarette smoking and changes in the histopathology of lung cancer. AB - BACKGROUND: Adenocarcinoma of the lung, once considered minimally related to cigarette smoking, has become the most common type of lung cancer in the United States. The increased incidence of this cancer might be explained by advances in diagnostic technology (i.e., increased ability to perform biopsies on tumors in smaller, more distal airways), changes in cigarette design (e.g., the adoption of filtertips), or changes in smoking practices. We examined data from the Connecticut Tumor Registry and two American Cancer Society studies to explore these possibilities. METHODS: Connecticut Tumor Registry data from 1959 through 1991 were analyzed to determine whether the increase in lung adenocarcinoma observed during that period could be best described by birth cohort effects (i.e., generational changes in cigarette smoking) or calendar period effects (i.e., diagnostic advances). Associations between cigarette smoking and death from specific types of lung cancer during the first 2 years of follow-up in Cancer Prevention Study I (CPS-I), initiated in 1959) and Cancer Prevention Study II (CPS-II, initiated in 1982) were also examined. RESULTS: Adenocarcinoma incidence in Connecticut increased nearly 17-fold in women and nearly 10-fold in men from 1959 through 1991. The increases followed a clear birth cohort pattern, paralleling gender and generational changes in smoking more than diagnostic advances. Cigarette smoking became more strongly associated with death from lung adenocarcinoma in CPS-II compared with CPS-I, with relative risks of 19.0 (95% confidence interval [CI] = 8.3-47.7) for men and 8.1 (95% CI = 4.5-14.6) for women in CPS-II and 4.6 (95% CI = 1.7-12.6) for men and 1.5 (0.3-7.7) for women in CPS-I. CONCLUSIONS: The increase in lung adenocarcinoma since the 1950s is more consistent with changes in smoking behavior and cigarette design than with diagnostic advances. PMID- 9362156 TI - Targeted interleukin-2 therapy for spontaneous neuroblastoma metastases to bone marrow. AB - BACKGROUND: Advanced (stage 4) cases of neuroblastoma, a childhood cancer of the nervous system, are associated with high relapse rates, even after intensive chemotherapy, radiotherapy, and autologous bone marrow transplantation. Therefore, the use of monoclonal antibodies directed against the neuroblastoma tumor marker disialoganglioside GD2 (GD2), in combination with recombinant human interleukin 2 (rhIL-2), is under clinical investigation. We hypothesize that targeted cytokine immunotherapy with a recombinant anti-GD2 antibody-interleukin 2 fusion protein (ch14.18-IL-2) is superior to a combination of ch14.18 and rhIL 2. Our purpose was as follows: 1) to develop a syngeneic model for murine neuroblastoma that expresses GD2 and features both experimental and spontaneous metastases to bone marrow and liver, and 2) to assess anti-GD2-targeted IL-2 therapy in this mode. METHODS: A hybrid neuroblastoma cell line was used to generate the GD2-positive NXS2 cell line. Bone marrow and liver metastases were quantified by reverse transcription-polymerase chain reaction for tyrosine hydroxylase and by organ weight or counts of macroscopic tumor foci, respectively. All P values reported are two-sided. RESULTS: Injection of NXS2 cells resulted in disseminated bone marrow and liver metastases exhibiting stable, but heterogeneous expression of GD2. Treatment with fusion protein (10 microg/day for 6 days) effectively suppressed growth of both experimental and spontaneous metastases to bone marrow and liver (P<.001). In contrast, a mixture of rhIL-2 and ch14.18 at equivalent dose levels was inefficient. Only mice treated with ch14.18-IL-2 showed a twofold prolongation in life span (P<.001). CONCLUSION: Targeted IL-2 therapy with a ch14.18-IL-2 fusion protein elicits an effective antitumor response. Our data suggest that a study of ch14.18-IL-2 as an adjuvant treatment in patients with minimal residual disease may be of value. PMID- 9362157 TI - Enhancing efficacy of recombinant anticancer vaccines with prime/boost regimens that use two different vectors. AB - BACKGROUND: The identification of tumor-associated antigens and the cloning of DNA sequences encoding them have enabled the development of anticancer vaccines. Such vaccines target tumors by stimulating an immune response against the antigens. One method of vaccination involves the delivery of antigen-encoding DNA sequences, and a number of recombinant vectors have been used for this purpose. To optimize the efficacy of recombinant vaccines, we compared primary and booster treatment regimens that used a single vector (i.e., homologous boosting) with regimens that used two different vectors (i.e., heterologous boosting). METHODS: Pulmonary tumors (experimental metastases) were induced in BALB/c mice inoculated with CT26.CL25 murine colon carcinoma cells, which express recombinant bacterial beta-galactosidase (the model antigen). Protocols for subsequent vaccination used three vectors that encoded beta-galactosidase--vaccinia (cowpox) virus, fowlpox virus, naked bacterial plasmid DNA. Mouse survival was evaluated in conjunction with antibody and cytotoxic T-lymphocyte responses to beta-galactosidase. RESULTS: Heterologous boosting resulted in significantly longer mouse survival than homologous boosting (all P<.0001, two-sided). Potent antigen-specific cytotoxic T lymphocytes were generated following heterologous boosting with poxvirus vectors. This response was not observed with any of the homologous boosting regimens. Mice primed with recombinant poxvirus vectors generated highly specific antibodies against viral proteins. CONCLUSIONS: The poor efficacy of homologous boosting regimens with viral vectors was probably a consequence of the induction of a strong antiviral antibody response. Heterologous boosting augmented antitumor immunity by generating a strong antigen-specific cytotoxic T lymphocyte response. These data suggest that heterologous boosting strategies may be useful in increasing the efficacy of recombinant DNA anticancer vaccines that have now entered clinical trials. PMID- 9362158 TI - Transplacental effects of 3'-azido-2',3'-dideoxythymidine (AZT): tumorigenicity in mice and genotoxicity in mice and monkeys. AB - BACKGROUND: When given during pregnancy, the drug 3'-azido-2',3'-dideoxythymidine (AZT) substantially reduces maternal-fetal transmission of human immunodeficiency virus type 1 (HIV-1). However, AZT has been shown to be carcinogenic in adult mice after lifetime oral administration. In this study, we assessed the transplacental tumorigenic and genotoxic effects of AZT in the offspring of CD-1 mice and Erythrocebus patas monkeys given AZT orally during pregnancy. METHODS: Pregnant mice were given daily doses of either 12.5 or 25.0 mg AZT on days 12 through 18 of gestation (last 37% of gestation period). Pregnant monkeys were given a daily dose of 10.0 mg AZT 5 days a week for the last 9.5-10 weeks of gestation (final 41%-43% of gestation period). AZT incorporation into nuclear and mitochondrial DNA and the length of chromosomal end (telomere) DNA were examined in multiple tissues of newborn mice and fetal monkeys. Additional mice were followed from birth and received no further treatment until subjected to necropsy and complete pathologic examination at 1 year of age. An anti-AZT radioimmunoassay was used to monitor AZT incorporation into DNA. RESULTS: At 1 year of age, the offspring of AZT-treated mice exhibited statistically significant, dose-dependent increases in tumor incidence and tumor multiplicity in the lungs, liver, and female reproductive organs. AZT incorporation into nuclear and mitochondrial DNA was detected in multiple organs of transplacentally exposed mice and monkeys. Shorter chromosomal telomeres were detected in liver and brain tissues from most AZT-exposed newborn mice but not in tissues from fetal monkeys. CONCLUSIONS: AZT is genotoxic in fetal mice and monkeys and is a moderately strong transplacental carcinogen in mice examined at 1 year of age. Careful long-term follow-up of AZT-exposed children would seem to be appropriate. PMID- 9362159 TI - High telomerase activity in primary lung cancers: association with increased cell proliferation rates and advanced pathologic stage. AB - BACKGROUND: Telomerase enzyme activity is not detected in most normal cells, a phenomenon believed to be associated with limitations on cellular proliferation. Since this activity is detected in nearly all human tumors, including non-small cell lung cancers, it has been suggested that telomerase activation may be coupled to acquisition of the malignant phenotype. In this study, we determined whether telomerase activity was associated with tumor pathologic stage, tumor cell proliferation rates, and clinical outcome in a cohort of patients with resected non-small-cell lung cancer for whom long-term follow-up was available. METHODS: Primary tumor specimens from 99 patients treated with surgery alone and six patients treated with surgery after chemotherapy were analyzed. Telomerase activity was measured by means of a modified Telomeric Repeat Amplification Protocol (TRAP) assay. Southern blot analysis of terminal restriction fragments was used to evaluate telomere length. Immunohistochemical analysis of Ki-67, a proliferation-associated nuclear antigen, was used to assess tumor cell proliferation. RESULTS: Telomerase activity was detected in 84 of the 99 tumors treated with surgery alone; this activity was not detected in specimens of adjacent, benign lung tissue. Telomerase was detected in only three of six tumors resected after chemotherapy. For the surgery-alone group, statistically significant positive associations were found between the level of telomerase activity and tumor stage, lymph node metastasis, pathologic TNM (tumor-node metastasis) stage, and Ki-67 immunostaining; a statistically significant inverse association was found between telomerase activity and patient age. No statistically significant differences in telomere length were found in relation telomerase activity or pathologic stage. Telomerase activity was not found to be associated with clinical outcome in a multivariate Cox proportional hazards analysis adjusted for tumor stage and lymph node status. CONCLUSIONS: High telomerase activity is detected frequently in primary non-small-cell lung cancers that exhibit high tumor cell proliferation rates and advanced pathologic stage. PMID- 9362160 TI - Interferon alfa versus chemotherapy for chronic myeloid leukemia: a meta-analysis of seven randomized trials: Chronic Myeloid Leukemia Trialists' Collaborative Group. AB - BACKGROUND: Several randomized clinical trials in chronic myeloid leukemia (CML) have reported better patient survival with interferon alfa (IFN alpha) than with standard chemotherapeutic agents, such as busulfan or hydroxyurea. However, the size and persistence of this survival benefit is uncertain. Our aim was to assess these reliably, both overall and in particular patient subgroups. METHODS: We collaborated in a worldwide overview of all clinical trials in which patients with CML were randomly assigned to receive either IFN alpha as the main drug or standard chemotherapy. Trials were identified by electronic and hand searching of the medical literature and databases and by personal contact. Individual patient data were available for each of 1554 patients who had been randomly assigned to treatment in seven trials (German, Italian, British, French, Japanese, and "Benelux"). Intention-to-treat stratified logrank survival analyses were performed, reporting two-sided P values. RESULTS: Almost all of the patients in these trials had disease with the Philadelphia chromosome abnormality. Among those who did, the regimens that involved IFN alpha produced a statistically significantly better survival than those involving either hydroxyurea (P = .001) or busulfan (P = .00007) alone. The 5-year survival rates were 57% with IFN alpha and 42% with chemotherapy, with an absolute difference of 15% (standard deviation = 3%; P<.00001). There were no trials or subgroups of patients in which the treatment difference was statistically significantly different from the average. CONCLUSION: For patients with Philadelphia chromosome-positive chronic myeloid leukemia, the inclusion of IFN alpha in the therapeutic regimen produced substantially better 5-year survival than standard chemotherapy alone. PMID- 9362161 TI - Telomerase activity for the preoperative diagnosis of pancreatic cancer. PMID- 9362162 TI - Short-term cessation of hormone replacement therapy and improvement of mammographic specificity. PMID- 9362163 TI - New toll-free hotline matches cancer patients with cancer survivors. PMID- 9362164 TI - Re: ethnic differences in estrogen metabolism in healthy women. PMID- 9362165 TI - Re: urokinase and urokinase receptor: association with in vitro invasiveness of human bladder cancer cell lines. PMID- 9362166 TI - Re: urokinase and urokinase receptor: association with in vitro invasiveness of human bladder cancer cell lines. PMID- 9362167 TI - Vinorelbine-induced pancreatitis: a case report. PMID- 9362168 TI - Re: five versus more than five years of tamoxifen therapy for breast cancer patients with negative lymph nodes and estrogen receptor-positive tumors. PMID- 9362169 TI - Re: probability of carrying a mutation of breast-ovarian cancer gene BRCA1 based on family history. PMID- 9362170 TI - Re: multiple neoplasias: an oncologic reality. PMID- 9362171 TI - Hepatitis G virus: clinical relevance and responsiveness to interferon. PMID- 9362172 TI - Treatment versus management of gastroesophageal reflux disease. PMID- 9362173 TI - "We used the Sydney System...". PMID- 9362174 TI - Guidelines on acute infectious diarrhea in adults. The Practice Parameters Committee of the American College of Gastroenterology. AB - Guidelines for clinical practice are intended to suggest preferable approaches to particular medical problems as established by the interpretation and collation of scientifically valid research, derived from an extensive review of published literature. When data are not available that will withstand objective scrutiny, a recommendation may be made based on a consensus of experts. Guidelines are intended to apply to the clinical situation for all physicians without regard to specialty. Guidelines are intended to be flexible, not necessarily indicating the only acceptable approach, and should be distinguished from standards of care that are inflexible and rarely violated. Given the wide range of choices in any health care problem, the physician should select the course best suited to the individual patient and the clinical situation presented. These guidelines are developed under the auspices of the American College of Gastroenterology and its Practice Parameters Committee. These guidelines are also approved by the governing boards of the American Gastroenterology Association and the American Society of Gastrointestinal Endoscopy. Expert opinion is solicited from the outset for the document. Guidelines are reviewed in depth by the Committee, with participation from experienced clinicians and others in related fields. The final recommendations are based on the data available at the time of the production of the document and may be updated with pertinent scientific developments at a later time. The following guidelines are intended for adults and not for pediatric patients. PMID- 9362175 TI - Contrast-enhanced gastrointestinal trans-abdominal and endoscopic ultrasonography: an idea whose time has come. PMID- 9362176 TI - Response to interferon of GB virus C and hepatitis C virus in patients with chronic hepatitis. AB - OBJECTIVES: To evaluate the response to interferon and capacity to induce liver disease of a putative non-A to E hepatitis virus designated GB virus C (GBV-C). METHODS: RNA of GBV-C was detected by reverse transcription polymerase chain reaction with nested primers deduced from the 5'-noncoding region. It was titrated, along with RNA of hepatitis C virus (HCV), in 16 co-infected patients (11%) out of 140 patients who received interferon. RESULTS: At the completion of a 6-month course of interferon (total dose: 516-774 million units), GBV-C RNA disappeared from serum in seven (44%) and HCV RNA from serum in 11 (69%) patients. At 6 months after interferon treatment ended, GBV-C RNA remained cleared in three patients (19%), and HCV RNA was persistently undetectable in four (25%). One patient lost both GBV-C and HCV RNAs. The three patients whose serum was cleared of GBV-C RNA had pretreatment titers of the virus (two with 10[1]/ml and one with 10[2]/ml) that were considerably lower than the titers of 13 patients (one with 10[2]/ml, eight with 10[3]/ml, and four with > or = 10[4]/ml) without such clearance. The decrease in alanine aminotransferase levels paralleled the response of HCV RNA but not that of GBV-C RNA to interferon. The response of HCV at 6 months after interferon in the co-infected patients (4/16 or 25%) did not differ significantly from that in patients without GBV-C infection (44/124 or 35%). CONCLUSIONS: The sensitivity of GBV-C to interferon is comparable to but independent of HCV. Co-infection with GBV-C does not influence the response to interferon of patients with chronic hepatitis C. PMID- 9362177 TI - Hepatitis G virus infection in hemodialysis patients and the effects of interferon treatment. AB - OBJECTIVE: To characterize the nature of hepatitis G virus (HGV) infections in hemodialysis patients and to determine the responsiveness of HGV to antiviral therapy in these patients. METHODS: HGV, a recently identified flavivirus, is associated with non-A-E viral hepatitis infections. We studied HGV infections in hepatitis C virus (HCV)-infected hemodialysis patients over a 1-yr period, using two independent PCR assays and nucleic acid sequencing. Thirty-four of 63 study patients were treated with interferon. RESULTS: We observed a 27% prevalence (17/63 patients) and a 4% annual incidence of HGV infections in the study population. HGV was not detected in any of the 10 HGV-infected patients immediately after interferon therapy. Although seven of these 10 patients developed HGV relapses, three had long-term responses. The interferon responsiveness of HGV and HCV appeared to be unrelated. In contrast, all seven untreated HGV-infected patients remained viremic. Sequence analyses of the different HGV isolates revealed only very limited genetic variability in the polymerase chain reaction-amplified regions of HGV during 1 yr of observation. CONCLUSIONS: Our data suggest that HCV-infected hemodialysis patients are at substantial risk of acquiring HGV infection and that HGV infections are prevalent in this population. In addition, HGV infections become chronic but are responsive to interferon treatment. PMID- 9362178 TI - Serum hepatitis G virus RNA in patients with chronic viral hepatitis. AB - OBJECTIVES: The hepatitis G virus (HGV) is a newly described flavivirus that affects a high proportion of patients with chronic viral hepatitis: our objective was to determine what role HGV might play in the course of disease. METHODS: We evaluated stored serum samples from 108 patients with chronic hepatitis B and 99 patients with chronic hepatitis C who participated in trials of alpha-interferon or ribavirin for the presence of hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA by branched DNA and for the presence of HGV RNA by polymerase chain reaction (PCR), using primers from the NS5 region of the genome. RESULTS: Initially, 20 (19%) patients with hepatitis B and 11 (11%) with hepatitis C had HGV RNA in their serum. Patients with and without HGV infection were similar with regard to clinical features, laboratory tests, and hepatic histology. HGV RNA levels fell during interferon therapy and became undetectable in those receiving the highest doses; however, HGV RNA levels returned to pretreatment values when therapy was stopped. With ribavirin therapy, HGV RNA levels did not change. Two- to 12-yr follow-up serum samples were available from 17 initially HGV RNA positive patients, of whom only 10 (59%) were still positive. CONCLUSIONS: HGV infection is common among patients with chronic hepatitis B and C but has little effect on the short-term course of disease or response to therapy. HGV RNA levels are suppressed but not eradicated by alpha-interferon and are unaffected by ribavirin treatment. Spontaneous loss of HGV RNA occurs over time in a proportion of patients. PMID- 9362179 TI - Omeprazole as a diagnostic tool in gastroesophageal reflux disease. AB - OBJECTIVE: To determine the diagnostic value of empirical treatment with omeprazole in the diagnosis of gastroesophageal reflux disease (GERD). METHODS: Patients with symptoms suggestive of GERD underwent upper gastrointestinal endoscopy and 24-h esophageal pH monitoring. Patients with reflux esophagitis grade 0 or 1 were included in the study and were randomized to double-blind treatment with either 40 mg omeprazole or placebo o.m. The effect of treatment was evaluated after 1 and 2 wk with a symptom questionnaire with a four-grade Likert scale, and symptomatic response outcome was compared with the results of 24-h pH-metry. RESULTS: Ninety-eight patients were included; however, 13 were excluded from the final analysis because of protocol violation. Of the remaining 85 patients, 54 had no signs of esophagitis at endoscopy, and 31 had esophagitis grade 1. The pH registration showed pathological gastroesophageal reflux in 47 patients (55%). Forty-one patients were randomized to treatment with omeprazole and 44 to placebo. There was a significant correlation between the pH registration result and response to omeprazole (p = 0.04, chi2), but not to placebo (p = 0.16). With pH-metry as the gold standard, the omeprazole test had positive and negative predictive values of 68% and 63%, respectively, for the diagnosis of GERD. When the omeprazole test was used as the gold standard, the positive and negative predictive values of pH monitoring were 68 % and 63 %, respectively. Similar sensitivity was found when the pH-metry was compared with presence of esophagitis. CONCLUSION: Determination of the symptomatic response to 40 mg of omeprazole for 14 days is a simple and inexpensive tool for the diagnosis of GERD, with a sensitivity and specificity comparable to 24-h pH monitoring. PMID- 9362180 TI - Endoscopic screening for dysplasia and mucosal aneuploidy in adolescents and young adults with childhood onset colitis. AB - OBJECTIVES: In adults, the premalignant nature of ulcerative colitis (UC) has long been accepted. Currently there is increasing concern that Crohn's disease (CD) may be equally premalignant. As a consequence, most adults with long standing UC and many with chronic CD are enrolled in ongoing endoscopic cancer surveillance programs. In contrast, the risk of colonic cancer in adolescents and young adults with either form of colitis is less well recognized, and the need for dysplasia and cancer screening in this population has not been systematically evaluated. We therefore report the prospective results of colonoscopic cancer screening in such a young population. METHODS: Thirty-five adolescents and young adults with long-standing colitis (18 UC, 17 CD; 21 +/- 3 yr old, 11 +/- 3 yr colitis duration) underwent colonoscopic cancer screening. All had multiple biopsies for flow cytometry and light microscopy. RESULTS: Seven subjects had aneuploidy (3/18 UC, 4/17 CD). Of these seven, only two had dysplasia [one high grade (UC), one low grade (CD)]. One additional subject had indefinite dysplasia with normal flow cytometry. The remaining 27 subjects had both normal flow cytometry and light microscopy. Five of the seven aneuploid subjects underwent surgery within 1 yr of screening. Four, including both subjects with dysplasia, had no evidence of colon cancer at surgery. However, a 24-yr-old female with a 14 yr history of UC and no evidence of dysplasia or cancer at screening had a Dukes C adenocarcinoma. CONCLUSIONS: Adolescents and young adults with childhood onset UC or CD are at risk for aneuploidy, dysplasia, and colon cancer. Aneuploidy can be evident 10 yr after the onset of colitis and in patients as young as 16 yr of age. Therefore, the risk for colon cancer in patients with childhood onset colitis must be based on the duration of the illness, not on their chronological age. Incorporation of flow cytometry into an endoscopic screening protocol appears to enhance the ability to identify individuals at highest risk for colon cancer. PMID- 9362181 TI - Features of symptomatic gastroesophageal reflux disease in elderly patients. AB - OBJECTIVES: Gastroesophageal reflux disease (GERD) is considered common in the elderly and may present with various symptoms, such as heartburn, regurgitation, dysphagia, or chest pain. In this study, we evaluated the patterns of symptomatic GERD and the spectrum of disease activity in the elderly. METHODS: We prospectively studied 476 predominantly male veterans who were referred for upper endoscopy because of symptoms or signs suggestive of upper gastrointestinal disease. All patients were interviewed immediately before the procedure by a physician who used a standardized symptom questionnaire. Endoscopic findings were categorized and graded according to their extent and severity. The prevalence, nature, and severity of esophageal symptoms and their relationship to endoscopic disease severity were then analyzed. Comparisons were made between two age groups, the young (age less than 65 yr old, mean age 55 yr, age range 30-65 yr), and the elderly (more than 66 yr old, mean age 72 yr, age range 66-90 yr). RESULTS: Heartburn without esophagitis was noted in 28% of young and 24% of elderly patients. Hiatal hernia without esophagitis was noted in 15 % of young and 18% of the elderly. The prevalence of various stages of GERD was similar in the two groups (p > 0.1, chi2 test; odds ratio: 0.983; 95% CI: 0.651-1.48). Quantitative esophageal symptom analysis revealed remarkably similar symptom severity scores for both groups for GERD stages I-IV, as well as for symptomatic controls. However, elderly patients with Barrett's esophagus were significantly less symptomatic than the young (symptom index 2.4 +/- 0.6 vs. 4.88 +/- 1.01, p < 0.02). CONCLUSIONS: Among symptomatic adults undergoing upper endoscopy, the elderly appear to have prevalence rates, patterns, and features of symptomatic GERD that are generally similar to those of their younger counterparts. Nevertheless, the severity of symptoms in the subgroup of elderly with Barrett's esophagus is significantly less than in the young and may contribute to poor or delayed recognition of disease. PMID- 9362182 TI - Dysplasia in short-segment Barrett's esophagus: a prospective 3-year follow-up. AB - OBJECTIVE: Short segments of intestinal metaplasia in the distal esophagus are being recognized with increasing frequency. Both long and short segments of Barrett's esophagus can progress to dysplasia and cancer. However, the risk of short-segment Barrett's esophagus (SSBE) for the development of dysplasia and adenocarcinoma of the esophagus is not yet known. Our purpose, therefore, was to determine the frequency with which dysplasia occurs in patients with SSBE. METHODS: Patients with SSBE were followed prospectively for the development of dysplasia. SSBE was defined as <3 cm of Barrett's-appearing epithelium above the gastroesophageal junction at endoscopy, with intestinal metaplasia on biopsy as documented by alcian blue stain at pH 2.5 on at least two endoscopic biopsies 6 months apart. Patients had interval upper endoscopy with systematic biopsy of the Barrett's segment. RESULTS: Fifty-nine SSBE patients were identified. The mean length of Barrett's mucosa was 1.5 +/- 0.1 cm; the mean age of the patients was 63.1 +/- 1.3 yr. Five patients had low-grade dysplasia (LGD) at initial endoscopy, for a prevalence of 8.5%; none had high grade dysplasia (HGD). Thirty two patients had follow-up endoscopy over a mean period of 36.9 +/- 5.4 months. Five of these patients developed dysplasia on follow-up, three with LGD and two with HGD, the incidence of any dysplasia being 5.7% per year. One patient with HGD that developed during surveillance progressed to adenocarcinoma of the esophagus over a 2-yr period. The other patient with HGD had LGD on follow-up endoscopy. Six patients with initial LGD had no evidence of dysplasia on follow up. CONCLUSIONS: The prevalence of dysplasia was 8.5% with an incidence of 5.7% per year in this group of SSBE patients, followed prospectively. Although dysplastic changes may not be identified on follow-up examination, some patients progress to adenocarcinoma. Therefore, we recommend surveillance endoscopy and biopsy in patients with SSBE just as in those with long-segment Barrett's esophagus. PMID- 9362183 TI - Immediate eradication of Helicobacter pylori in patients with previously documented peptic ulcer disease: clinical and economic effects. AB - OBJECTIVES: The clinical and economic benefits of Helicobacter pylori eradication for patients with newly diagnosed peptic ulcer disease are widely accepted. The objective of this study was to estimate the cost-effectiveness of H. pylori eradication in the large cohort of asymptomatic patients receiving maintenance antisecretory therapy for a previously documented peptic ulcer disease. METHODS: A decision analytic model estimated the clinical and economic effects of two management strategies for asymptomatic patients receiving maintenance antisecretory therapy for a previously documented peptic ulcer: strategy 1 immediate H. pylori eradication therapy and cessation of maintenance therapy, and strategy 2-continued-maintenance antisecretory therapy, with H. pylori eradication therapy reserved for the first symptom recurrence. RESULTS: At 1 yr, the model estimated that immediate H. pylori eradication therapy (strategy 1) led to 22% fewer months with ulcers (28.7 vs. 36.8 ulcer months/100 patient years), 10% fewer months with ulcer symptoms (21.0 vs. 23.1 symptom months/100 patient years), and 24% lower per-patient expenditures ($587 vs. $767/patient year) than maintenance antisecretory therapy and symptom-based H. pylori eradication (strategy 2). Immediate H. pylori eradication, however, resulted in 14% more months with upper gastrointestinal symptoms from all causes (37.9 vs. 33.2 symptom months/100 patient years) than strategy 2, because maintenance antisecretory therapy was effective in treating symptoms due to causes other than peptic ulcer disease. CONCLUSIONS: Ulcer-related outcomes of asymptomatic patients receiving maintenance antisecretory agents for peptic ulcer disease can be improved with immediate H. pylori eradication at reduced cost. Therefore, H. pylori eradication should be aggressively pursued in all patients-symptomatic or not-with previously documented peptic ulcers, who are receiving maintenance antisecretory therapy. PMID- 9362184 TI - Helicobacter pylori recurrence after successful eradication: 5-year follow-up in the United States. AB - OBJECTIVES: We previously reported a 3.4% posttreatment Helicobacter pylori recurrence rate over 18 months. We undertook to establish the rate of reinfection in our United States cohort up to 80 months after successful therapy. METHODS: Previously studied patients who had successful triple therapy for H. pylori during 1989-92 were identified. Baseline infection had been established by the presence of H. pylori on antral biopsies as well as positive [13C]urea breath tests. Eradication of H. pylori had been confirmed by repeat endoscopy and breath test 4 wk after therapy. Three of four subjects reported that H. pylori recurrences had occurred in the first year after therapy. Patients remaining free of infection were invited back for follow-up breath test in 1995-1996. RESULTS: One hundred fourteen patients were identified: 56 were unavailable or were using medications that would interfere with H. pylori testing. The remaining 58 patients (50.9%) included 32 M/26 F, mean age 62.9 yr. The mean follow-up period was 58 months, range 34-80 months. Positive breath tests occurred in 2/58 patients (3.4%) at 54 and 70 months after therapy. Both patients reported recurrent epigastric symptoms. The H. pylori recurrence rate for our group was 3.4% over the 4 yr since their last evaluation, or 0.85% recurrence per year. Defining recurrence as reinfection occurring after 1 yr, the total recurrence rate for the group over the 5 yr since treatment was 3/59 patients (5.1%), or 1.0% H. pylori recurrence per year posttreatment. CONCLUSIONS: The rate of H. pylori reinfection after successful therapy is low in the United States and approximates 1% per year. PMID- 9362185 TI - Omeprazole plus clarithromycin and either tinidazole or tetracycline for Helicobacter pylori infection: a randomized prospective study. AB - OBJECTIVE: Helicobacter pylori has begun to show resistance to imidazoles and could result in the low efficacy of short-term triple therapy. The aim of this study was to assess whether administration of tetracycline instead of tinidazole in short-term low-dose triple therapy could increase the H. pylori eradication rate. METHODS: In a prospective study, 113 patients with peptic ulcer (n = 36) or non-ulcer dyspepsia (n = 77) were randomized to receive 1-wk treatment, composed of omeprazole 20 mg b.i.d., clarithromycin 250 mg b.i.d., and either tinidazole 500 mg b.i.d. (n = 57) or tetracycline 500 mg b.i.d. (n = 56), upon detection of H. pylori infection at endoscopy. RESULTS: H. pylori eradication, defined as a negative bacterial finding in a rapid urease test and upon histologic assessment at least 4 wk after cessation of therapy, was achieved in 86% (49 of 57; 95% confidence interval = 76.9-95) of patients in the first group and in 71.4% (40 of 56; 95% confidence interval = 59.6-83.3) in the second group (p = not significant). Side effects occurred in 28% of patients from the tinidazole-based group and in 12.5% from the tetracycline group (p = not significant). Two patients in the tinidazole group discontinued therapy at 5 and 6 days because of side effects. CONCLUSIONS: The administration of tetracycline instead of tinidazole in short-term triple therapy yielded disappointing results in H. pylori eradication. PMID- 9362186 TI - Does pancreatic enzyme supplementation reduce pain in patients with chronic pancreatitis: a meta-analysis. AB - OBJECTIVE: Pancreatic enzyme therapy is widely used in the treatment of pain in chronic pancreatitis. The aim of our study was to perform a meta-analysis to determine whether pancreatic enzyme supplementation significantly decreases abdominal pain in patients with chronic pancreatitis. METHODS: From a MEDLINE search, we identified, evaluated, and subjected to a meta-analysis, six randomized, double-blind, placebo-controlled trials. Important features of data extraction included the method of subject inclusion, definition of disease, enzyme preparation, response to pancreatic enzyme therapy versus placebo, and modality for measuring response. RESULTS: In the meta-analysis, the pooled estimate of the percentage of patients per study who preferred enzymes relative to placebo was 52% (95% confidence interval, 45-60%). A test of homogeneity indicated that there was no statistically significant heterogeneity across studies in the percentage of patients preferring enzymes. CONCLUSION: Statistical analysis demonstrates no significant benefit of supplemental pancreatic enzyme therapy to relieve pain associated with chronic pancreatitis. PMID- 9362187 TI - Five-year follow-up of asymptomatic patients with negative fecal occult blood test results in whom clinically significant colorectal pathology was detected. AB - OBJECTIVES: To determine from a 5-yr longitudinal study (a) rate of compliance with follow-up, (b) number of new clinically significant colorectal lesions discovered by sigmoidoscopy or colonoscopy at later examination, (c) number and causes of deaths, and (d) rate of diagnosis of new cancers among 36 asymptomatic patients with negative fecal occult blood tests in whom clinically significant colorectal lesions were found initially by 60-cm flexible sigmoidoscope. METHODS: For the 36 patients, medical records were reviewed throughout the 5-yr study period. These records included pathology reports, results from 60-cm sigmoidoscopy and colonoscopy examinations, and notations from visits to health facilities for reasons other than colorectal examinations. RESULTS: Seventy-one clinically significant lesions were removed during the 5-yr period; 58 were discovered by sigmoidoscopy and 13 by colonoscopy. Also, during the 5-yr period, noncolorectal cancer was diagnosed in six patients, and two patients died of cardiac disease. CONCLUSIONS: Patients who have clinically significant colorectal pathology found by 60-cm sigmoidoscope have a high prevalence of lesions beyond the view of this instrument. Therefore, colonoscopy should be performed when sigmoidoscopy shows clinically significant pathology. Because subsequent examinations show a high incidence of new lesions, rescreening is indicated. PMID- 9362188 TI - Reduced chemoreceptor sensitivity in patients with Barrett's esophagus may be related to age and not to the presence of Barrett's epithelium. AB - BACKGROUND: Patients with Barrett's esophagus have demonstrated reduced chemo- and mechanoreceptor sensitivity to acid infusion and balloon distension, respectively. However, Barrett's esophagus is mainly a disease of the elderly, making age the possible underlying mechanism for altered pain perception in this patient population. OBJECTIVES: To determine perception thresholds to acid infusion in elderly (>65 yr) versus younger (< or =50 yr) patients with Barrett's esophagus. METHODS: Twelve elderly and 10 younger patients, matched by length of Barrett's mucosa, were recruited into the study. All patients participated in our Barrett's esophagus surveillance program. The patients were treated with omeprazole 20 to 60 mg/day and were symptom free. Chemosensitivity was determined by a modified acid perfusion test, in which acid perception thresholds were quantified by the lag time to initial typical symptom perception, sensory intensity rating, and an acid perfusion sensory score. RESULTS: Five of the elderly patients with Barrett's esophagus had a negative test, whereas all younger patients with Barrett's esophagus experienced typical symptom perception during acid infusion. Elderly patients with Barrett's esophagus had significantly longer lag time to initial perception, lower acid perfusion sensory score, and sensory intensity rating in comparison with the younger patients. CONCLUSIONS: Reduced chemoreceptor sensitivity to acid perfusion that has previously been demonstrated in patients with Barrett's esophagus may be related to age and not to the presence of Barrett's epithelium. PMID- 9362189 TI - Study of prevalence, severity, and etiological factors associated with acute pancreatitis in patients infected with human immunodeficiency virus. AB - OBJECTIVES: Patients with the human immunodeficiency virus (HIV) disease can develop pancreatic gland inflammation from HIV infection and related causes, or from factors totally independent of it. The incidence and severity acute pancreatitis in patients with HIV diseases and the frequency of associated etiological factors have not been examined in any detail. The purpose of this study was to (a) determine the prevalence of acute pancreatitis, (b) evaluate severity of pancreatic gland inflammation, (c) identify commonly associated etiological factors with acute pancreatitis, and (d) examine the relationship between CD4 lymphocyte counts and serum pancreatic enzyme levels (amylase and lipase) in patients with HIV disease. METHODS: We examined the medical records of 321 patients with HIV disease seen at Sinai Hospital of Baltimore between July of 1993 to June of 1994. Data collected from these records included clinical, laboratory, and radiologic features of pancreatitis, staging of HIV disease, risk factors, CD4 lymphocyte counts, medications associated with the presence of opportunistic infections, Kaposi's sarcoma, and lymphoma. RESULTS: From 321 patients with HIV disease, 45 patients developed at least one episode of acute pancreatitis as defined by clinical and laboratory criteria during the 1-yr period. A statistically significant negative correlation was found between serum pancreatic enzyme level and the number of CD4 lymphocytes (r = -0.15, p < 0.05 for serum amylase; r = -0.2, p < 0.05 for serum lipase). Furthermore, patients with asymptomatic HIV infection or CD4 lymphocyte count >500 mm3 did not develop asymptomatic hyperamylasemia or acute pancreatitis. Furthermore, the presence of gallstones, active injection drug use, pentamidine therapy, Pneumocystis carinii, Mycobacterium avium intracellulare correlated significantly (p < 0.001) with the diagnosis of acute pancreatitis. CONCLUSIONS: A detailed review of medical records of patients with HIV disease seen in a community hospital in 1 yr (1993 1994) suggests a high incidence (14%) of mild to moderately severe acute pancreatitis. In this group of patients, pancreatic gland inflammation is commonly associated with gallstones, intravenous drug abuse, pentamidine intake, and Pneumocystis carinii and Mycobacterium avium intracellulare infections. In addition, marked reduction in CD4 lymphocyte count is associated with increase in serum pancreatic enzyme levels (amylase, lipase activity) suggesting pancreatic gland inflammation or altered pancreatic enzyme turnover. PMID- 9362190 TI - Effects of bolus volume on oropharyngeal swallowing: an electrophysiologic study in man. AB - OBJECTIVE: Different variables of oropharyngeal swallowing change in response to bolus volume and consistency as determined by manometric/videofluoroscopic studies. But the subject is debatable especially from the physiologic point of view. No electrophysiologic studies are available on human subjects. METHODS: The effects of bolus volume and viscosity on different variables of oropharyngeal swallowing were investigated using electrophysiologic methods. Mechanical upward and downward laryngeal movements and submental electromyographic (SM-EMG) activity of the laryngeal elevator muscles were recorded during dry and 3-, 10-, and 20-ml water swallowing in 14 normal subjects. Cricopharyngeus (CP) muscle was investigated during 3- and 10-ml water swallowing in 10 normal subjects. Semisolid and liquid swallowing were compared in eight normal subjects. RESULTS: The total duration of SM-EMG, time necessary for larynx elevation, CP-EMG pause related with upper esophageal sphincter opening and swallowing variability (jitter) all increased significantly with increasing bolus volume. Laryngeal superior relocation time and CP-EMG pause were shorter for semisolid swallowing compared with swallowing the same amount of liquid. CONCLUSION: The duration of SM-EMG activity, laryngeal upward-downward movements, and CP-EMG pause are affected by sensory inputs such as volume and viscosity of the bolus swallowed. The results indicate that sensory input modifies the central swallowing pattern although basic events remain the same in normal human subjects. PMID- 9362191 TI - Functional measurement of nonfibrotic hepatic mass in cirrhotic patients. AB - OBJECTIVES: We have postulated that the perfused hepatic mass (PHM) can be estimated by quantitative (volumetric) liver spleen scan (QLSS) using single photon emission computed tomography assessment of sulfur colloid distribution between liver, spleen, and bone marrow. Thus, this parameter should correlate with the amount of functioning tissue in the liver. As a "gold standard" estimate of the nonfibrotic functioning hepatic mass, the weight of the liver at autopsy or transplant was corrected for the amount of scar tissue present. QLSS parameters were correlated with functional hepatic mass in 13 patients with advanced liver disease with liver available at transplant (8 patients) or autopsy (5 patients) who had prior QLSS. METHODS: Greater than 1000 mm2 of a liver tissue was assessed histologically in all patients and from more than 2 regions of the liver in 9 of 13 patients. The total fibrosis score (TFS) (range, 0-17.5) was calculated as a semiquantitative estimate of hepatic fibrosis. The ratio of functioning tissue was calculated as (1 - TFS/20) and the amount of functioning tissue as the nonfibrotic weight (NFW): NFW = liver weight x (1--TFS/20). QLSS parameters were measured postprandially and 30 min after injection of 5 mCi of technetium Tc 99m sulfur colloid. Pixel and total counts from the liver, spleen, and bone marrow as well as organ length were measured. Liver/bone marrow index and liver/spleen index were calculated. The perfused hepatic mass (PHM) was defined as the mean of the liver/bone marrow index and liver/spleen index. RESULTS: All patients had cirrhosis: alcoholic (1 patient), alcoholic with alcoholic hepatitis (1 patient), hepatitis B (3 patients), hepatitis C (6 patients), hepatitis C with hepatocellular carcinoma (1 patient), and primary sclerosing cholangitis (n = 1). The ratio of functioning tissue was 0.54 +/- 0.07; liver weight 1215 +/- 317 g; and NFW = 658 +/- 193 g. The PHM = 55 +/- 14. The PHM calculated from the QLSS correlated strongly with the NFW (functioning tissue) at autopsy/transplant: NFW = 13 PHM - 55; r = 0.9505; p < 0.0001). CONCLUSIONS: In cirrhotic patients (a) we have confirmed that the sulfur colloid distribution by QLSS is determined by the perfused hepatic mass, and (b) the amount of functioning tissue can be precisely estimated by QLSS parameters. PMID- 9362192 TI - Plasma vitamin K1 level is decreased in primary biliary cirrhosis. AB - OBJECTIVE: To measure directly plasma vitamin K1 in patients with primary biliary cirrhosis (PBC) and to examine the relationship between vitamin K1 level, prothrombin time, other fat-soluble vitamin levels, and severity of cholestasis. METHODS: We directly measured levels of vitamin K1 (phylloquinone) in the plasma of 77 patients with PBC using reverse-phase high-performance liquid chromatography, along with serum levels of vitamins A, E, and 25-OH vitamin D. RESULTS: Median plasma vitamin K1 level was significantly lower in PBC patients compared with 255 normal subjects (0.65 nmol/L; range, 0.05-4.13, vs 0.95 nmol/L; range, 0.2-4.92; p < 0.0001). Of 77 PBC patients, 18 (23%) patients had levels below the normal range for plasma vitamin K1 (<0.3 nmol/L). Only 1 of the 18 patients with decreased vitamin K1 had a prolonged prothrombin time. There was no correlation between vitamin K1 level and prothrombin time in the PBC patients (p = 0.75); there was also no difference in prothrombin time between PBC patients with low vitamin K1 level and PBC patients with normal vitamin K1 level (10.3 vs 10.0 seconds; p = 0.28). PBC patients with decreased vitamin K1 levels had significantly lower vitamin A and vitamin E levels, and significantly higher serum bilirubin levels than those with normal vitamin K1 levels. CONCLUSION: Decreased plasma vitamin K1 level is common in PBC, and is associated with decreased serum levels of vitamins A and E. However, the majority of PBC patients with decreased plasma vitamin K1 levels have normal prothrombin times. Although the prothrombin time is an insensitive marker of vitamin K1 status in PBC patients, clinically important vitamin K deficiency seems uncommon. PMID- 9362194 TI - Risk factors for gallbladder polyps in the Chinese population. AB - OBJECTIVES: To assess the prevalence of and risk factors for gallbladder (GB) polyps in the Chinese population. METHODS: A prospective ultrasonographic study of GB polyps was conducted in 3647 Chinese subjects who received a paid physical checkup at this hospital. Their demographic characteristics and biochemical parameters were recorded. Ultrasonographic diagnosis revealed a normal GB in 2946 subjects (1838 men, 1108 women), polyps in 243 (174 men, 69 women), gallstones in 286 (196 men, 90 women), a history of cholecystectomy in 100 (56 men, 44 women), mixed gallstones/GB polyps in 17 (10 men, seven women), and miscellaneous results in 35. RESULTS: Excluding subjects with cholecystectomy and mixed gallstones/GB polyps, the overall prevalence of GB polyps in the study group was 6.9%. The studied risk factors manifesting an increased odds ratio (OR) for the development of GB polyps were glucose intolerance (OR 1.506, p < 0.05) and male gender (OR 1.723, p < 0.05) in multivariate analysis. Other demographic characteristics and biochemical parameters, such as age, body mass index, cigarette smoking, alcohol consumption, blood pressure, lipid profile, hepatitis B virus carrier, liver function, and parity, did not exhibit any correlation to GB polyps. CONCLUSIONS: Among Chinese of higher socioeconomic status, men and individuals with glucose intolerance tend to have a high risk for developing GB polyps. PMID- 9362193 TI - Ileal carcinoid tumors stimulating Crohn's disease: incidence among 176 consecutive cases of ileal carcinoid. AB - OBJECTIVE: There are seven published cases of ileal carcinoid tumor misdiagnosed and treated as Crohn's disease. We evaluated 176 consecutive ileal carcinoid patients to determine the frequency with which this occurs. Clinical, hormonal, and radiographic data of those patients misdiagnosed were also analyzed to determine whether there were clinical lessons to be learned. METHODS: Records of 176 patients with ileal carcinoid tumors were retrospectively reviewed. It was determined whether patients were diagnosed and treated for Crohn's before the diagnosis of carcinoid was established. Radiographic, hormonal, and clinical data were reviewed and comparison was made to those who were correctly diagnosed as having carcinoid. RESULTS: Of 176 ileal carcinoid patients, 4 were initially diagnosed and treated as having Crohn's; their mean age was 51.5 +/- 8.9 yr. The hormonal data of patients treated as Crohn's was indistinguishable from patients with known carcinoid. Two of four patients had colonoscopy performed, neither had terminal ileal intubation. None responded to medical therapy and all required surgery for diagnosis. The mean time from symptom onset to the establishment of the correct diagnosis was 24 +/- 6.9 months with a range of 6 to 45 months. CONCLUSIONS: Although rare, ileal carcinoid tumors may be misdiagnosed as Crohn's disease. In our study approximately 2.3% of patients with ileal carcinoid were initially diagnosed and treated as having Crohn's disease. The presence of disease refractory to medical therapy should alert clinicians to this possibility and urinary 5-HIAA levels should be obtained as a screening test. PMID- 9362195 TI - F2-isoprostane and 4-hydroxynonenal excretion in human bile of patients with biliary tract and pancreatic disorders. AB - OBJECTIVE: To assess parameters of lipid peroxidation in bile of patients with hepatobiliary and pancreatic diseases. METHODS: F2-isoprostanes (F2-IPs) and 4 hydroxynonenal (4-HNE) were measured in bile collected during 31 ERCP procedures using gas chromatography/mass spectrometry. RESULTS: In 11 subjects with normal ERCP (controls), bile contained significant amounts of F2-IPs (188 +/- 27 pg/ml) and 4-HNE (37.5 +/- 8.0 ng/ml). In 10 individuals with bile duct stones, there was a 3-fold increase of F2-IPs (523 +/- 129 pg/ml; p < 0.05) and a 2.5-fold increase of 4-HNE (89.6 +/- 18.0 ng/ml; p < 0.05). In 10 patients with various pancreatic diseases, bile F2-IPs were also enhanced (545 +/- 112 pg/ml; p < 0.01). There was no significant change in alpha-tocopherol, whereas beta-carotene was decreased in biliary tract and pancreatic diseases (p < 0.05). Results of serum liver tests were normal with the exception of bilirubin, which was increased together with alkaline phosphatase. Concentrations of total lipids, phospholipids, and cholesterol did not differ significantly between the three groups. CONCLUSIONS: These data provide the first evidence in humans supporting the role of oxidative stress in the pathogenesis of biliary and pancreatic disease. PMID- 9362196 TI - Pharmacological modulation of rectal tone alters perception of distention in humans. AB - OBJECTIVE: Drugs can alter perception of balloon distention of the GI tract. It has been proposed that the mechanism by which this occurs is through effects on visceral afferent pathways. Our hypothesis was that modulation of rectal tone will also influence the perception of rectal balloon distention. METHODS: Fasting and postprandial rectal tone, compliance, and perception of rectal distention were measured in 25 healthy subjects, using a five-armed, parallel, single blinded study design. Each subject received either glucagon, nitroglycerin, clonidine, yohimbine, or saline. RESULTS: Rectal tone, but not compliance, influenced perception as measured by balloon distention of the rectum (r = 0.6, p = 0.002). Glucagon, nitroglycerin, and clonidine reduced and yohimbine increased fasting tone compared with saline. Compliance and postprandial tone were similar in all groups. Yohimbine increased rectal perception of distention. CONCLUSIONS: Tone is one of the factors that influences the sensory perception of balloon distention in the human rectum. Alpha2-adrenergic agents, a nitric oxide donor, and glucagon altered fasting rectal tone, but postprandial tone was similar after administration of each agent. PMID- 9362197 TI - Plasma substance P levels in patients with liver cirrhosis: relationship to systemic and portal hemodynamics. AB - OBJECTIVES: Nitric oxide has been proposed as being responsible for the hyperdynamic circulation observed in portal hypertensive states. Substance P, a neuropeptide partly cleared by liver, induces vasodilation through the activation of the endothelial nitric oxide pathway. This study investigated the plasma levels of substance P in cirrhotic patients and the relationship of these levels to systemic and portal hemodynamics. METHODS: Sixty-four patients with cirrhosis and 53 healthy controls had blood samples taken for determining plasma values of substance P by ELISA. Systemic and portal hemodynamics were measured on the same day of blood sampling using a Swan-Ganz catheterization and thermodilution technique. RESULTS: Plasma levels of substance P were higher in cirrhotic patients than in healthy controls (45.7 +/- 2.0 vs 32.9 +/- 1.0 pg/ml, p < 0.001) and directly correlated with Child-Pugh's score (r = 0.52, p < 0.0001). Compared with compensated cirrhotic patients, decompensated cirrhotic patients had higher plasma levels of substance P accompanied by a lower systemic vascular resistance and higher hepatic venous pressure gradient. There was no significant correlation between plasma levels of substance P and systemic vascular resistance and hepatic venous pressure gradient. In addition, no significant difference in plasma levels of substance P was observed between cirrhotic patients with and cirrhotic patients without a hepatic venous pressure gradient > 12 mm Hg or between patients with and patients without large esophageal varices. CONCLUSIONS: Plasma levels of substance P are increased in patients with cirrhosis and may contribute to the pathogenesis and/or maintenance of hyperdynamic circulation in decompensated patients. The severity of cirrhosis is more important than portal hypertension and the severity of esophageal varices for the development of increased plasma substance P levels. PMID- 9362198 TI - Splanchnic hemodynamic pattern and liver function in patients with cirrhosis and esophageal or gastric varices. AB - OBJECTIVES: This study was designed to characterize the splanchnic hemodynamic pattern and liver function in patients with cirrhosis and esophageal or gastric varices. METHODS: Forty control subjects and 112 patients with cirrhosis were studied. Portal inflow (the sum of superior mesenteric arterial and splenic arterial flows), portal venous flow, and collateral flow (the difference between portal inflow and portal venous flow) were measured using duplex ultrasonography. Endoscopic examination showed that 45 patients had no varices or small esophageal or gastric varices, 49 had large esophageal varices, and 18 had large gastric varices. Liver function was assessed by Pugh-Child score. RESULTS: Portal inflow was significantly greater in patients with large esophageal varices or large gastric varices than in control subjects and patients with no varices or small esophageal or gastric varices. Portal venous flow was significantly lower in patients with large gastric varices than in the other three groups. Collateral flow was significantly greater in patients with large gastric varices than in patients with large esophageal varices. The Pugh-Child score was significantly higher in patients with large gastric varices than in patients with large esophageal varices. The Pugh-Child score was also inversely correlated with portal venous flow (r = -0.35, p < 0.01) and directly correlated with collateral flow (r = 0.59, p < 0.01). CONCLUSIONS: Both patients with esophageal varices and those with gastric varices have increased portal inflow. However, patients with gastric varices, in contrast to patients with esophageal varices, have a reduced portal venous flow associated with an increased collateral flow. Such a portal outflow pattern may contribute to the worse liver function seen in patients with gastric varices. PMID- 9362199 TI - Factors responsible for computed electrogastrographic parameters in humans. AB - OBJECTIVES: Clinical knowledge about myoelectrical frequency is well known, but the factors responsible for recorded myoelectrical amplitude remain less clear. METHODS: We assembled an electrogastrographic system that could automatically compute the dominant myoelectrical frequency and power and power ratio. We enrolled 50 healthy volunteers (25 men and 25 women) to study their myoelectrical characteristics. Three surface electrodes were placed in the fundic, stomach body, and antral positions for two 30-min recordings in the fasting and postprandial states. RESULTS: The three different electrodes recorded similar dominant frequencies of about 3 cpm before and after a meal. The fasting dominant powers from these electrodes were 52.9 +/- 14.7, 44.6 +/- 11.5, and 50.1 +/- 15.1 dB, respectively (p < 0.01), whereas the postprandial dominant powers were 61.6 +/- 28.8, 54.3 +/- 26.6, and 61.9 +/- 27.8 dB, respectively (p < 0.01). Meal ingestion did increase the power (p < 0.05). Women had a lower dominant power than men (p < 0.001). Moreover, the dominant powers of each electrode were significantly correlated with body mass index (r = 0.3-0.36, p < 0.05) regardless of meal ingestion. The postprandial power ratio was not influenced by electrode position, gender, or body mass index. CONCLUSIONS: Myoelectrical dominant frequencies and power ratios are similar throughout the whole stomach area, whereas a lower power area exists on the stomach body. Gender-related variation in dominant power seems to be an effect of body size. The power ratio is the only reliable parameter for expressing myoelectrical amplitude. PMID- 9362200 TI - Conservative management of small adenomata in ulcerative colitis. AB - OBJECTIVE AND METHODS: Patients with chronic ulcerative colitis may develop colitis-related dysplasia and/or sporadic adenomata. Differentiating between these two processes is important because they may dictate different therapeutic approaches. Although distinguishing features of sporadic adenomata versus colitis related dysplasia have been suggested previously on an a priori basis, they have never been verified by follow-up analysis. We have identified six chronic ulcerative colitis patients whose discrete adenomata were managed conservatively, with subsequent continuation in their surveillance programs. RESULTS: Mean patient age was 69 yr with a mean 21.3 yr of ulcerative colitis. Surveillance endoscopy of 63 patient-yr duration yielded 24 adenomata. A mean follow-up after the initial adenoma diagnosis was 7.2 yr with no carcinoma identified (including the examination of one prophylactic colectomy specimen). One patient, with a 34 yr history of ulcerative colitis and a single sporadic adenoma subsequently developed dysplasia of flat mucosa 14 months later. CONCLUSIONS: Our findings concur with previous reports and indicate that small, discrete adenomata with morphology identical to those seen in the general population occur in patients with ulcerative colitis. Such lesions in patients older than 45 yr, with tubular or tubulovillous architecture and low-grade dysplasia, are effectively treated by polypectomy only and are not necessarily an indication for colectomy. However, sporadic adenomata and colitis-related dysplasia can develop metachronously. It is suggested that subsequent to a diagnosis of sporadic adenoma in a patient with chronic ulcerative colitis, surveillance should increase to colonoscopic examination every 6 to 12 months. PMID- 9362202 TI - Aeromonas sobria-associated left-sided segmental colitis. AB - Aeromonas species, once thought pathogenic only in immunocompromised hosts, have more recently been found to be associated with many different infections in previously healthy individuals. The most common site of these infections is the gastrointestinal tract. We describe a 67-yr-old woman who presented with abdominal pain and bloody diarrhea and was diagnosed with left-sided, segmental colitis due to Aeromonas sobria, which was proven by stool culture. Extensive work-up for ischemic colitis was unremarkable, and after treatment with antibiotics, the patient's symptoms resolved, and follow-up colonoscopy failed to reveal any evidence of residual colitis or inflammatory bowel disease. Our report supports the view that Aeromonas species need to be considered in the differential diagnosis of colitis, and we believe it to be the first report of left-sided, segmental colitis secondary to Aeromonas sobria infection. PMID- 9362203 TI - Effect of octreotide on gastrostomy, duodenostomy, and cholecystostomy effluents: a physiologic study of fluid and electrolyte balance. AB - OBJECTIVES: Octreotide, a somatostatin analog, reduces stool and fistula outputs by a mechanism that is not completely understood. Our aim was to study its effect on gastrostomy, duodenostomy, and cholecystostomy effluents in a patient with colorectal cancer. METHODS: Effluents of gastrostomy, duodenostomy, and cholecystostomy were collected in three separate shifts over 24-h periods beginning 3 days before octreotide therapy and continuing for 15 treatment days. Fifty-four samples were tested for volume, pH, acid, and bicarbonate production, and biochemical profiles. RESULTS: A positive fluid balance was achieved immediately with octreotide therapy. Significant decreases in gastrostomy and duodenostomy outputs and in gastric acid production were observed (1433.33 +/- 33.33 ml/24 h to 535.71 +/- 55.31 ml/24 h,p < 0.0001; 2066.67 +/- 66.67 ml/24 h to 247.14 +/- 36.04 ml/24 h, p < 0.0001; and 67.50 +/- 3.20 mEq/h to 13.00 +/- 1.50 mEq/h, p < 0.0001; respectively). Gastrostomy tachyphylaxis was observed after 6 days of treatment. Remarkable dose-dependent increases were found in cholesterol and bilirubin concentrations in the cholecystostomy effluent. CONCLUSIONS: Octreotide's primary effect is a decrease in gastric and pancreatic secretions. The increased concentrations of cholesterol and bilirubin may explain the occurrence of gallstones in patients treated with octreotide. PMID- 9362201 TI - Large particle biopsy by the "band-snare" technique. PMID- 9362204 TI - Fulminant pseudomembranous colitis caused by clindamycin phosphate vaginal cream. PMID- 9362205 TI - Terlipressin may influence the outcome of hepatorenal syndrome complicating alcoholic hepatitis. AB - Hepatorenal syndrome is a frequent complication associated with extremely short survival in cirrhotic patients with alcoholic hepatitis. Vasopressin analogs have been reported to induce transient regression of hepatorenal syndrome in patients with cirrhosis. However, treatment withdrawal was followed by early recurrences in every case. We report the case of a 68-yr-old woman with severe alcoholic hepatitis complicated by hepatorenal syndrome. Terlipressin induced a prolonged recovery of renal function that was associated with improvement in hepatic function. PMID- 9362206 TI - A case of Meckel's diverticulum complicated by stenosis of the colon. AB - Meckel's diverticulum is a common anomaly of the GI tract that is known to cause small intestinal obstruction. A 17-yr-old male who had no history of previous surgery was admitted with intermittent abdominal pain. A barium enema showed extraintestinal compression of the ascending colon, suggesting the existence of a congenital band. Laparoscopy revealed that the ascending colon was lifted up and compressed by the intestinal end of a Meckel's diverticulum with a fibrous band connecting to the umbilicus. The portion of the ileum including the Meckel's diverticulum was resected. This is the first case of stenosis of the colon caused by a Meckel's diverticulum. PMID- 9362207 TI - Gastritis secondary to herpes simplex virus. AB - Gastric infection with herpes simplex virus is rare, with only two cases previously reported. At the time of the previous reports, the virus could not be cultured, and the diagnosis was based on histological findings. Two cases of culture positive herpes simplex virus gastritis are presented, emphasizing the importance of routine gastric biopsies and viral cultures in immunodeficient patients with dyspeptic symptoms. PMID- 9362208 TI - A case of alveolar echinococcosis restricted to the pancreas. PMID- 9362209 TI - Carcinoid tumor associated with vascular malformation as a cause of massive gastric bleeding. AB - Massive gastric bleeding in a 28-yr-old woman requiring emergency surgical treatment was found to originate from a polypoid carcinoid tumor 1.3 cm in diameter. Histologically, the tumor was found to be associated with a complex vascular malformation apparently originating from the underlying submucosa, crossing the tumor and ending in large mucosal sinusoids that opened on the mucosal surface. A similar clinical presentation was reported in three previous cases of small gastric carcinoids, one of which revealed an anomalous intratumoral bleeding artery. We recommend that in the absence of more common causative lesions of gastric bleeding, gastric carcinoid be considered in cases of focal massive hemorrhage requiring emergency treatment. PMID- 9362210 TI - Acute pancreatitis occurring in gastric aberrant pancreas accompanied by paralytic ileus. PMID- 9362211 TI - Isolated common bile duct tuberculosis mimicking malignant obstruction. PMID- 9362212 TI - Ulcerative colitis presenting with bronchiolitis obliterans organizing pneumonia in a pediatric patient. PMID- 9362213 TI - Weber-Christian syndrome after endoscopic retrograde pancreatography. PMID- 9362214 TI - Lymphocytic colitis in a pediatric patient: a possible adverse reaction to carbamazepine. PMID- 9362216 TI - TIPS for patients with refractory hepatic hydrothorax: what is the take-home message? PMID- 9362215 TI - Antiphospholipid antibody syndrome presenting as acute acalculous cholecystitis. PMID- 9362217 TI - Cutting through to the chafe of the problem? PMID- 9362218 TI - Is the only good H. pylori a dead H. pylori? PMID- 9362219 TI - Is endoscopic common bile duct stenting useful in patients with suspected sphincter of Oddi dysfunction? PMID- 9362220 TI - Onset of ulcerative colitis during immunosuppressive therapy for liver transplantation. PMID- 9362221 TI - Could there be an aspirin good to your stomach? PMID- 9362222 TI - Re: Yousfi et al. comparing the agar gel (CLOtest) to a reagent strip (PyloriTek) rapid urease test. PMID- 9362223 TI - Does selective intra-arterial injection of calcium stimulate insulin secretion in all insulinoma cases? PMID- 9362224 TI - Effect of vasoactive drugs on carotid diameter in humans. AB - We studied whether vasoactive drugs used to determine baroreflex sensitivity influence baroreceptor firing by affecting carotid sinus smooth muscle or simply by stretching the sinus wall through changes in pressure. In six young healthy subjects, the diameter of the carotid artery and its change with arterial pulse were measured with ultrasonography. Blood pressure was measured by Finapres. Phenylephrine and nitroglycerin doses were injected intravenously to raise and lower pressure by approximately 15-25 mmHg. Carotid dimensions increased in all subjects during the phenylephrine-induced rise and decreased during the nitroglycerin-induced fall in pressure. Diastolic diameter changed more than systolic diameter; changes were significantly different from the control value (assessed by single-factor analysis of variance and Scheffe's post hoc test). The systolic pressure-diameter relationship appeared to be nonlinear, with a steeper slope above than below baseline, and contributed significantly to the nonlinearity of the R-R interval-systolic pressure relationship. It is concluded that during drug-induced changes in blood pressure, baroreceptor activity in humans is influenced more by passive stretch than by local smooth muscle contraction. PMID- 9362225 TI - Priming effect of adenosine on K(ATP) currents in intact ventricular myocytes: implications for preconditioning. AB - Activation of protein kinase C (PKC) by the phorbol ester phorbol 12-myristate 13 acetate (PMA) has been shown to shorten the time to turn on ATP-sensitive potassium currents (I(K,ATP)) during metabolic inhibition (MI) but only when adenosine (Ado) is included. In the present study we tested whether pretreatment with Ado could mimic the effect of PMA in isolated rabbit ventricular myocytes. When I(K,ATP) was measured by conventional whole cell clamp, pretreatment with 100 microM Ado did not alter the time to I(K,ATP) activation: 13.5 +/- 2.1 vs. 12.4 +/- 1.9 min with Ado during MI. We repeated the experiment using the perforated patch technique. Consistent with the previous results in conventional whole cell patch recordings, the time to turn on I(K,ATP) during MI (with Ado included) was shortened from 27.1 +/- 2.2 to 12.6 +/- 2.4 min (P < 0.01) when cells were pretreated with PMA and Ado was included during MI. In contrast to conventional whole cell recordings, Ado pretreatment also abbreviated the time for I(K,ATP) activation during MI (with Ado included) to 16.4 +/- 1.8 min. This effect was partially eliminated by simultaneous administration of an Ado receptor blocker or a PKC inhibitor during Ado pretreatment, suggesting that pretreatment with Ado stimulates PKC by activating Ado receptors. Our results demonstrate that Ado can prime I(K,ATP) during subsequent MI in the presence of Ado. This priming effect appears to be mediated by PKC upregulation of the channel. These results support the notion that Ado plays a dual role to initiate and to mediate ischemic preconditioning and links the roles of Ado receptors, PKC, and I(K,ATP) in ischemic preconditioning. PMID- 9362226 TI - Endothelium-dependent vasodilation in the brachial artery is impaired in smokers: effect of vitamin C. AB - Cigarette smoking has been shown to cause endothelial dysfunction. To examine the effects of vitamin C and cigarette smoking on endothelium-dependent vasodilation, we measured the lumen diameter and flow velocity of the brachial arteries at rest, during reactive hyperemia following transient arterial occlusion, and after sublingual nitroglycerin (0.3 mg) in smokers (n = 20) and nonsmokers (n = 20) with high-resolution ultrasound after infusion of saline or saline plus vitamin C (10 mg/min for 20 min). We also performed the same study in smokers (n = 15) before and 10 min after cigarette smoking. In addition, we measured the serum levels of vitamin C and the plasma levels of thiobarbituric acid-reactive substances (TBARS) as an index of lipid peroxidation. The smokers had lower vitamin C levels, higher TBARS levels, and showed impairment of flow-dependent vasodilation (5.3 +/- 1.9 vs. 9.2 +/- 1.5%, P < 0.0001) compared with nonsmokers. Vitamin C administration improved the impairment of flow-dependent vasodilation (5.3 +/- 1.9 to 9.0 +/- 3.2%, P < 0.001) and decreased TBARS in smokers but not in nonsmokers. Furthermore, cigarette smoking acutely worsened the impairment of flow-dependent vasodilation (5.4 +/- 1.8 to 1.5 +/- 1.3%, P < 0.01) and increased TBARS. We conclude that 1) endothelium-dependent vasodilation in the brachial arteries is impaired in smokers and this impairment is improved by vitamin C administration in association with a decrease in TBARS and 2) cigarette smoking produces acute impairment of endothelium-dependent vasodilation in smokers in association with an increase in TBARS. PMID- 9362227 TI - Late preconditioning against stunning is not mediated by increased antioxidant defenses in conscious pigs. AB - Previous studies in conscious pigs have demonstrated that a sequence of ten 2-min coronary occlusion/2-min reperfusion cycles renders the heart relatively resistant to myocardial stunning 24 h later [late preconditioning (PC) against stunning] by an unknown mechanism. Since oxygen radicals contribute importantly to myocardial stunning and since antioxidant enzymes have been reported to be upregulated 24 h after PC in dogs and rabbits, we tested the hypothesis that late PC against stunning is related to an increase in endogenous antioxidant defenses. Chronically instrumented conscious pigs underwent a sequence of ten 2-min coronary occlusion/2-min reperfusion cycles (preconditioned group, n = 11) or received no intervention (control group, n = 5). Twenty-four hours later, pigs were killed and the myocardial levels of Mn superoxide dismutase (SOD), Cu-Zn SOD, catalase, glutathione (GSH) peroxidase, GSH reductase, GSH, GSH disulfide, alpha-tocopherol, and ascorbate were measured. There were no differences in any of the enzymatic or nonenzymatic antioxidants between the ischemic and nonischemic regions in the preconditioned group or between the control and the preconditioned group. Thus, when a marked protection against stunning was present (24 h after PC), no alteration in antioxidant defenses was observed. These results indicate that, in conscious pigs, late PC against myocardial stunning is not mediated by increased endogenous antioxidant defenses, thereby refuting one of the major current hypotheses regarding this phenomenon. PMID- 9362228 TI - Mechanism of atrioventricular nodal facilitation in rabbit heart: role of proximal AV node. AB - The phenomenon of atrioventricular (AV) nodal "facilitation," described in traditional "black box"-functional studies, implies enhanced AV nodal dromotropic function. We investigated the role of atrial prematurities in the modulation of the nodal cellular responses in the mechanism of AV nodal facilitation. Atrial and His (H) bundle electrograms and microelectrode recordings from proximal AV nodal cells were analyzed in 15 superfused rabbit AV node preparations. The pacing protocol consisted of 30 basic beats (S1; coupling interval S1-S1 = 300 ms) followed by a facilitating prematurity (S2; coupling intervals S1-S2 of 300, 200, 150, and 130 ms) followed by the test beat (S3; coupling interval S2-S3 scanned in 5-ms steps). Conduction curves (S2-H2 vs. S1-S2, S3-H3 vs. S2-S3, and S3-H3 vs. H2-S3) were constructed. Facilitation (i.e., shortening of S3-H3 when S1-S2 was shortened) was demonstrated in all preparations using the H2-S3 (P < 0.001) but not the S2-S3 format. Microelectrode recordings revealed a causal relationship between the improved proximal AV nodal cellular responses in facilitation and the prolonged S2-S3 interval. There was no evidence for enhanced nodal dromotropic function directly resulting from the introduction of the facilitating beats. Thus facilitation is based on inherent cycle-length-dependent properties of the AV node during application of a complex pacing protocol and primarily reflects the uncontrolled modulation of the proximal cellular response. PMID- 9362229 TI - Role of beta1- and beta2-adrenergic receptors in regulation of Cl- and Ca2+ channels in guinea pig ventricular myocytes. AB - The role of beta1- and beta2-adrenergic receptor stimulation in modulating adenosine 3',5'-cyclic monophosphate (cAMP)-regulated Cl- and Ca2+ currents was investigated with use of guinea pig ventricular myocytes. Activation of the Cl- current by the nonselective beta-receptor agonist isoproterenol (Iso) was not affected by the beta2-receptor antagonist ICI-118,551 (ICI), but it was blocked by the beta1-receptor antagonist atenolol. The inability of beta2-receptor stimulation to activate the Cl- current was confirmed by the lack of response to the selective beta2-receptor agonists salbutamol and zinterol. Responses to beta2 adrenergic receptor stimulation were also looked for in pertussis toxin (PTX) treated myocytes because PTX increases the sensitivity of responses to Iso, and PTX has been reported to increase the responsiveness to beta2- but not beta1 receptor stimulation. PTX treatment increased the sensitivity of the Cl- current to activation by Iso in the presence of ICI, indicating that PTX increases beta1 receptor responsiveness. PTX treatment also resulted in the ability of salbutamol to activate the Cl- current. However, the response to salbutamol was blocked by atenolol but not by appropriate concentrations of ICI, suggesting that salbutamol was activating beta1-receptors. These results indicate that PTX treatment increases the sensitivity to beta1-receptor stimulation, without affecting beta2 responsiveness. To verify that the lack of response to beta2-receptor stimulation was not unique to the Cl- current, the effects of beta2-receptor agonists on the L-type Ca2+ current were also examined. The Ca2+ current was only affected by high concentrations of zinterol or salbutamol, and such responses were blocked by atenolol, but not by ICI, suggesting that activation of beta1-receptors was involved. These results indicate that beta1- but not beta2-adrenergic receptor stimulation plays an important role in modulating the cAMP-regulated Cl- and Ca2+ currents in guinea pig ventricular myocytes. PMID- 9362230 TI - Adenosine inhibition of neutrophil damage during reperfusion does not involve K(ATP)-channel activation. AB - This study tests the hypothesis that cardioprotection exerted by adenosine A2 receptor activation and neutrophil-related events involves stimulation of ATP sensitive potassium (K(ATP)) channels on neutrophils during reperfusion. The adenosine A2 agonist CGS-21680 (CGS) inhibited superoxide radical generation from isolated rabbit polymorphonuclear neutrophils (PMNs) in a dose-dependent manner from 17.7 +/- 2.1 to 7.4 +/- 1.3 nmol/5 x 10(6) PMNs (P < 0.05). Pinacidil, a K(ATP)-channel opener, partially inhibited superoxide radical production, which was completely reversed by glibenclamide (Glib). Incremental doses of Glib in combination with CGS (1 microM) did not alter CGS-induced inhibition of superoxide radical generation. CGS significantly reduced PMN adherence to the endothelial surface of aortic segments in a dose-dependent manner from 189 +/- 8 to 50 +/- 6 PMNs/mm2 (P < 0.05), which was also not altered by incremental doses of Glib. Infusion of CGS (0.025 mg/kg) before reperfusion reduced infarct size from 29 +/- 2% in the Vehicle group to 15 +/- 1% in rabbits undergoing 30 min of ischemia and 120 min of reperfusion (P < 0.05). Glib (0.3 mg/kg) did not change the infarct size (28 +/- 2%) vs. the Vehicle group and did not attenuate infarct size reduction by CGS (16 +/- 1%). Glib did not change blood glucose levels. Cardiac myeloperoxidase activity was decreased in the ischemic tissue of the CGS group (0.15 +/- 0.03 U/100 mg tissue) compared with the Vehicle group (0.37 +/- 0.05 U/100 mg tissue; P < 0.05). We conclude that adenosine A2 activation before reperfusion partially reduces infarct size by inhibiting neutrophil activity and that this effect does not involve K(ATP)-channel stimulation. PMID- 9362231 TI - MCI-154, a Ca2+ sensitizer, decreases the oxygen cost of contractility in isolated canine hearts. AB - An increase in the responsiveness of the contractile machinery to Ca2+ could theoretically enhance the mechanoenergetics of the heart. To clarify this unresolved issue, we studied the effects of MCI-154, a Ca2+ sensitizer, on the mechanoenergetics in terms of the left ventricular contractility index [slope of end-systolic pressure-volume relationship (Emax)] and the relationship between myocardial oxygen consumption (VO2) and left ventricular pressure-volume area in excised cross-circulated canine hearts. MCI-154 increased Emax by 42 +/- 31% (SD), although the slope of the VO2-PVA relationship (an indicator of contractile efficiency) was unchanged by MCI-154. Despite equal increases in Emax, the relative increase in unloaded VO2 (delta VO2/delta Emax) during infusion of MCI 154 was, however, significantly less than that during CaCl2 infusion (0.0016 +/- 0.0018 vs. 0.0059 +/- 0.0054; P < 0.05). By contrast, delta VO2/delta Emax for milrinone was the same as that for CaCl2 (0.0043 +/- 0.0041 vs. 0.0039 +/- 0.0045; P > 0.05). Basal metabolism in KCl-arrested hearts was unchanged by MCI 154, indicating that MCI-154 consumes less energy than CaCl2 for excitation contraction coupling. These findings suggest that MCI-154 acts energetically as a Ca2+ sensitizer in beating canine whole hearts. PMID- 9362232 TI - Stimulation of left stellate ganglion prolongs Q-T interval in patients with palmar hyperhidrosis. AB - With the advent of transthoracic video-assisted endoscopic electrocautery of the second and the third sympathetic ganglia for the treatment of palmar hyperhidrosis, it is possible to approach the stellate ganglia with ease. To see whether stimulation of stellate ganglia in humans is similar to the case in dogs, we stimulated the sympathetic ganglia in 18 palmar hyperhidrosis patients with a coagulation power of 5 W at a frequency of three times every 2 s. We found that left stellate stimulation prolongs the Q-T interval and increases the heart rate, whereas right stellate stimulation affects the Q-T interval and heart rate insignificantly, just like the case in dogs in which the left stellate ganglion predominates the right one in determining the Q-T interval. Left stellate stimulation after destruction of the left second and third ganglia also prolongs the Q-T interval, suggesting that the left stellate ganglion is more important in determining the Q-T interval. PMID- 9362233 TI - Structural properties of rat mesenteric small arteries after 4-wk exposure to elevated or reduced blood flow. AB - We determined the structure of mesenteric small arteries after chronic elevation and chronic reduction of blood flow. In 6-wk-old rats, we ligated second-order side branches of every other first-order side branch of the superior mesenteric artery. This persistently reduced blood flow (-90%) in the vessels feeding into the ligated trees and elevated blood flow (+80%) in the nonligated mesenteric artery side branches. Four weeks after surgery, vessels that had been exposed to high blood flow (HF) or low blood flow (LF) and vessels from sham-operated rats (Sham) were isolated and mounted in a pressure myograph system. At an intraluminal pressure of 100 mmHg, the internal diameter at rest was larger in HF (533 +/- 23 microm) and smaller in LF (262 +/- 14 microm) than in Sham vessels (427 +/- 15 microm). Also, wall and media cross-sectional areas were larger in HF and smaller in LF than in Sham vessels (media: 22 +/- 1, 11 +/- 2, and 16 +/- 1 x 10(3) microm2, respectively), but circumferential wall stress did not differ among groups. DNA content was significantly increased in HF vessels (+100%) and was not modified in LF vessels. Maximal vasoconstrictions elicited by high potassium or norepinephrine were slightly increased in HF vessels but were reduced by 50% in LF vessels. Thus chronic changes in blood flow give rise to structural changes that normalize circumferential wall stress. Elevated blood flow resulted in outward hypertrophic remodeling involving hyperplasia. Reduced blood flow resulted in inward hypotrophic remodeling accompanied by hyporeactivity of the arterial smooth muscle. PMID- 9362234 TI - Limb ischemia preconditions the heart against reperfusion tachyarrhythmia. AB - We investigated the hypothesis that a cardioprotective, antiarrhythmic effect might be obtained by brief ischemia of a remote part of the body before ischemia of the heart. Regional ischemia (RI) was induced in isolated Langendorff-perfused rat hearts: group I, 30-min RI and reperfusion (control hearts; n = 18); group II, 5-min RI before 30-min RI (a reference group of "classic" ischemic preconditioning; n = 12); and group III, ischemic preconditioning with in vivo 10 min limb ischemia (LI) before 30-min RI in the perfused heart (n = 20). A significant decrease in reperfusion arrhythmia was found in groups II and III compared with group I (P < 0.02). Release of norepinephrine (NE) and prostacyclin was higher in hearts from animals pretreated with LI (P < 0.05). Prostacyclin increased in all groups at minute 1 of reperfusion, but there was no correlation to the antiarrhythmic effect. NE increased at the beginning of reperfusion after 30 min of ischemia; this release was significantly diminished after preconditioning with LI (P < 0.05). We further investigated the role of NE in preconditioning with LI using drug interventions. Pretreatment with exogenous NE protected against tachyarrhythmia. Reserpine given 24 h before LI partially abolished the antiarrhythmic effect of LI preconditioning. However, the alpha1 adrenoreceptor blocker prazosin did not prevent the effect of LI preconditioning on either ischemic or reperfusion tachyarrhythmia. Therefore, brief ischemia of an extremity protects against reperfusion tachyarrhythmia. One of the humoral mediators involved in this response appears to be NE; others remain to be identified. PMID- 9362235 TI - Beta-adrenoceptors in vascular capacitance responses to unloading of carotid baroreceptors in anesthetized dogs. AB - The role of beta- and alpha-adrenoceptors in the total vascular capacitance responses to changing pressure in vascularly isolated carotid sinuses of anesthetized and atropinized dogs was investigated. A change in vascular capacitance was determined by measuring the shift of blood in and out of a reservoir that was connected to the aorta and maintained at a constant pressure. Changes in carotid sinus pressure from 135 to 57 mmHg and back to 137 mmHg resulted in a rapid vascular capacitance response of approximately 30 ml in the absence of adrenoceptor antagonists. Administration of a beta2-adrenoceptor antagonist (ICI-118551) caused a significant enhancement of the capacitance responses to similar decreases and increases in carotid sinus pressure (approximately 130%). Administration of a beta1-adrenoceptor antagonist (CGP 20712A) did not cause any further enhancement of the responses. However, an alpha blocker (phentolamine) reduced the responses by 75%. The results suggest that in the presence of a beta2-adrenoceptor antagonist vascular capacitance responses to loading and unloading of baroreceptors are greatly enhanced and that patients suffering from orthostatic syncope may benefit from this kind of drug. PMID- 9362236 TI - PDGF-BB decreases systolic blood pressure through an increase in macrovascular compliance in rats. AB - The cardiovascular roles of platelet-derived growth factor (PDGF) were examined in anesthetized rats by monitoring blood pressure and in isolated blood vessels and heart preparations. Intravenous injection of PDGF-BB lowered blood pressure. The decrease in systolic pressure was greater than that in diastolic pressure, so the pulse pressure decreased. PDGF-AA and -AB, other isoforms of PDGF, did not have any effect on blood pressure. Pretreatment of rats with N(omega)-nitro-L arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) synthase, shortened duration of the hypotensive effect of PDGF-BB. The administration of L arginine with L-NAME partially prevented the effect of L-NAME. PDGF-BB relaxed aortic rings precontracted with phenylephrine with a 50% effective concentration of 3 ng/ml. In contrast, in isolated mesenteric vascular preparations, the vasodilating activity of PDGF-BB was observed only at a high concentration (>12.5 ng/ml). In isolated heart preparations, PDGF-BB had no effect on the beat rate or contractile activity. These results suggest a new role of PDGF-BB that may contribute to the regulation in circulation through the increase in macrovascular compliance mediated by NO. PMID- 9362237 TI - Transient, isopeptide-specific induction of myocardial endothelin-1 mRNA in congestive heart failure in rats. AB - Increased myocardial expression of preproendothelin-1 (ppET-1) mRNA has been associated with congestive heart failure (CHF) in rats. However, the time course and isoform pattern of ppET mRNA induction and the cellular localization of ET in failing hearts are unknown. Thus our aim was to investigate myocardial ppET mRNA expression in CHF rats during the first 6 wk after induction of myocardial infarction. Furthermore, performing immunohistochemical analysis, we also investigated the origin and localization of immunoreactive endothelin (ET) in different regions of the failing heart. Ribonuclease protection assays revealed a marked increase in ppET-1 mRNA levels in rat myocardial tissues during CHF. The induction of ppET-1 mRNA was isopeptide specific and transient. The most substantial upregulation was observed in the infarcted area, where maximal expression of ppET-1 mRNA was observed after 7 days (25-fold increase, P < 0.05). However, a marked and statistically significant induction of ppET-1 mRNA was also observed in the nonischemic myocardium. Immunohistochemical analysis revealed ET 1-like immunoreactivity in cardiomyocytes, vascular endothelial cells, macrophages, and proliferating fibroblasts. Thus immunohistochemistry revealed the structural basis for the dramatic upregulation of the myocardial ET system in the infarcted region, suggesting a role for ET in the healing process after myocardial infarction. However, the global upregulation of ppET-1 mRNA in the heart also suggests an autocrine/paracrine regulatory mechanism in the nonischemic myocardium during CHF. PMID- 9362238 TI - Autoreceptor-induced inhibition of neuropeptide Y release from PC-12 cells is mediated by Y2 receptors. AB - Pheochromocytoma (PC)-12 cells express Y1, Y2, and Y3 neuropeptide Y (NPY) receptors when differentiated with nerve growth factor (NGF). The present work evaluated NGF-differentiated PC-12 cells as a model system to study modulation of NPY release by NPY autoreceptors. We demonstrated that both K+ and nicotine stimulated concomitant release of NPY and dopamine from differentiated PC-12 cells. We also showed in this study that NPY release from PC-12 cells was attenuated in a concentration-dependent manner by peptide YY (PYY)-(13-36), a selective agonist for the Y2 type of NPY receptors. This result demonstrated that NPY release could be modulated by NPY autoreceptors of the Y2 subtype. The inhibitory action of PYY-(13-36) may be mediated at least in part by inhibition of N-type Ca2+ channels, because PYY-(13-36) could not produce further inhibitory effects in the presence of a maximum effective concentration of omega-conotoxin, an N-type Ca2+-channel blocker. The inhibition by PYY-(13-36) could be blocked by pretreatment of cells with pertussis toxin, suggesting that an inhibitory GTP binding protein was involved. Furthermore, the function of NPY autoreceptors could be modulated by other receptors such as beta-adrenergic and ATP receptors. The evoked release of NPY was also attenuated by ATP and adenosine, which have been shown to be colocalized and coreleased with NPY from sympathetic nerve terminals. These results suggest that PC-12 cells differentiated with NGF may be an ideal model to study regulatory mechanisms of NPY release and that autoreceptor-mediated regulation of NPY release appears to act through the Y2 subtype of the NPY receptor. PMID- 9362239 TI - Dual effects of endothelins on the muscarinic K+ current in guinea pig atrial cells. AB - Effects of endothelins (ETs) on the acetylcholine receptor-operated K+ current (I(KACh)) were examined in isolated guinea pig atrial cells using patch-clamp techniques. ET-1 or ET-3 produced a transient activation of I(KACh) in atrial cells held at -40 mV. When I(KACh) was preactivated by 1 microM carbachol, however, both ETs produced a transient potentiation followed by a sustained inhibition of the current. When I(KACh) was maximally activated by 10 microM carbachol or 100 microM adenosine, these ETs produced only a sustained inhibition of the I(KACh). Their inhibitory effects on the preactivated I(KACh) were concentration dependent, and the half-maximal effective concentrations were 314 pM for ET-1 and 1.13 nM for ET-3. The inhibitory effect of ET-1 was antagonized by BQ-485, a specific ET(A) receptor antagonist, but not by BQ-788, a specific ET(B) receptor antagonist, indicating that the ET-1 effect is mediated by ET(A) receptors. On the other hand, the inhibitory effect of ET-3 was antagonized by BQ 788 and more effectively by BQ-485, suggesting the involvement of "atypical" ET receptors. Both ETs partly reversed the carbachol-induced shortening of the action potential recorded in the current-clamp mode. Inhibitory effects of ET-1 and ET-3 on the preactivated I(KACh) may contribute to the positive inotropic and chronotropic effects of ETs in atrial tissues. PMID- 9362240 TI - Incidence of arrhythmias and heart rate variability in wild-type rats exposed to social stress. AB - Psychological stressors of different natures can induce different shifts of autonomic control on cardiac electrical activity, with either a sympathetic or a parasympathetic prevalence. Arrhythmia occurrence, R-R interval variability, and plasma catecholamine elevations were measured in male wild-type rats exposed to either a social stressor (defeat) or a nonsocial challenge (restraint). Electrocardiograms were telemetrically recorded, and blood samples were withdrawn through jugular vein catheters from normal, freely moving animals. Defeat produced a much higher incidence of arrhythmias (mostly ventricular premature beats), which were mainly observed in the 60-s time periods after attacks. The social challenge also induced a much stronger reduction of average R-R interval, a lower R-R interval variability (as estimated by the time-domain parameters standard deviation of mean R-R interval duration, coefficient of variance, and root mean square of successive differences in R-R interval duration), and higher elevations of venous plasma catecholamines compared with restraint. These autonomic and/or neuroendocrine data indicate that a social stressor such as defeat is characterized by both a higher sympathetic activation and a lower parasympathetic antagonism compared with a nonsocial restraint challenge, which results in a higher risk for ventricular arrhythmias. PMID- 9362241 TI - Sleep and circadian influences on cardiac autonomic nervous system activity. AB - To assess the separate contributions of the sleep and circadian systems to changes in cardiac autonomic nervous system (ANS) activity, 12 supine subjects participated in two 26-h constant routines, which were counterbalanced and separated by 1 wk. One routine did not permit sleep, whereas the second allowed the subjects to sleep during their normal sleep phase. Parasympathetic nervous system activity was assessed with respiratory sinus arrhythmia as measured from the spectral analysis of cardiac beat-to-beat intervals. Sympathetic nervous system activity was primarily assessed with the preejection period as estimated from impedance cardiography, although the 0.1-Hz peak from the spectral analysis of cardiac beat-to-beat intervals, the amplitude of the T wave in the electrocardiogram, and heart rate were also measured. Respiratory sinus arrhythymia showed a 24-h rhythm independent of sleep, whereas preejection period only showed a 24-h rhythm if sleep occurred. Thus the findings indicate that parasympathetic nervous system activity is mostly influenced by the circadian system, whereas sympathetic nervous system activity is mostly influenced by the sleep system. PMID- 9362242 TI - Angiotensin II formation from ACE and chymase in human and animal hearts: methods and species considerations. AB - The current study examined the contributions of angiotensin-converting enzyme (ACE) vs. chymase to angiotensin II (ANG II) generation in membrane preparations from left ventricles of humans, dogs, rabbits, and rats and from total heart of mice. ACE and chymase activity were measured in membrane preparations extracted with low or high detergent (LD and HD, respectively) concentrations. We hypothesized that ACE, which is membrane bound in vivo, would be preferentially localized to the HD preparation, whereas chymase, which is localized to the cytoplasm and cardiac interstitium, would be localized to the LD preparation. In human heart, ACE activity was 16-fold higher in the HD than in the LD preparation, whereas chymase activity was 15-fold higher in the LD than in the HD preparation. Total ANG II formation was greater in human heart [15.8 +/- 3.4 (SE) micromol ANG II x g(-1) x min(-1)] than in dog, rat, rabbit, and mouse hearts (3.90 +/- 0.35, 0.41 +/- 0.02, 0.61 +/- 0.07, and 1.16 +/- 0.08 micromol ANG II x g(-1) x min(-1), respectively, P < 0.05, by analysis of variance). ANG II formation from ACE was higher in mouse heart (1.09 +/- 0.05 micromol ANG II x g( 1) x min(-1), p < 0.001) than in rabbit, human, dog, and rat hearts (0.55 +/- 0.06, 0.34 +/- 0.01, 0.32 +/- 0.06, and 0.31 +/- 0.02 micromol ANG II x g(-1) x min(-1), respectively). In contrast, chymase activity was higher in human heart (15.3 +/- 3.4 micromol ANG II x g(-1) x min(-1)) than in dog, rat, rabbit, and mouse hearts (3.59 +/- 0.29, 0.10 +/- 0.01, 0.06 +/- 0.01, and 0.07 +/- 0.01 micromol ANG II x g(-1) x min(-1), respectively). Our results demonstrate important species differences in the pathways of intracardiac ANG II generation. Chymase predominated over ACE activity in human heart, accounting for extremely high total ANG II formation in human heart compared with dog, rat, rabbit, and mouse hearts. PMID- 9362243 TI - Modulation of Kv4 channels, key components of rat ventricular transient outward K+ current, by PKC. AB - Current evidence suggests that members of the Kv4 subfamily may encode native cardiac transient outward current (I(to)). Antisense hybrid-arrest with oligonucleotides targeted to Kv4 mRNAs specifically inhibited rat ventricular I(to), supporting this hypothesis. To determine whether protein kinase C (PKC) affects I(to) by an action on these molecular components, we compared the effects of PKC activation on Kv4.2 and Kv4.3 currents expressed in Xenopus oocytes and rat ventricular I(to). Phorbol 12-myristate 13-acetate (PMA) suppressed both Kv4.2 and Kv4.3 currents as well as native I(to), but not after preincubation with PKC inhibitors (e.g., chelerythrine). An inactive stereoisomer of PMA had no effect. Phenylephrine or carbachol inhibited Kv4 currents only when coexpressed, respectively, with alpha1C-adrenergic or M1 muscarinic receptors (this inhibition was also prevented by chelerythrine). The voltage dependence and inactivation kinetics of Kv4.2 were unchanged by PKC, but small effects on the rates of inactivation and recovery from inactivation of native I(to) were observed. Thus Kv4.2 and Kv4.3 proteins are important subunits of native rat ventricular I(to), and PKC appears to reduce this current by affecting the molecular components of the channels mediating I(to). PMID- 9362244 TI - Cardiovascular responses to dynamic exercise with acute anemia in humans. AB - We hypothesized that reducing arterial O2 content (CaO2) by lowering the hemoglobin concentration ([Hb]) would result in a higher blood flow, as observed with a low PO2, and maintenance of O2 delivery. Seven young healthy men were studied twice, at rest and during two-legged submaximal and peak dynamic knee extensor exercise in a control condition (mean control [Hb] 144 g/l) and after 1 1.5 liters of whole blood had been withdrawn and replaced with albumin [mean drop in [Hb] 29 g/l (range 19-38 g/l); low [Hb]]. Limb blood flow (LBF) was higher (P < 0.01) with low [Hb] during submaximal exercise (i.e., at 30 W, LBF was 2.5 +/- 0.1 and 3.0 +/- 0.1 l/min for control [Hb] and low [Hb], respectively; P < 0.01), resulting in a maintained O2 delivery and O2 uptake for a given workload. However, at peak exercise, LBF was unaltered (6.5 +/- 0.4 and 6.6 +/- 0.6 l/min for control [Hb] and low [Hb], respectively), which resulted in an 18% reduction in O2 delivery (P < 0.01). This occurred despite peak cardiac output in neither condition reaching >75% of maximal cardiac output (approximately 26 l/min). It is concluded that a low CaO2 induces an elevation in submaximal muscle blood flow and that O2 delivery to contracting muscles is tightly regulated. PMID- 9362245 TI - Blood pressure and heart rate variability in early pregnancy in rats. AB - Changes in the autonomic control of the circulation may contribute to the maternal hemodynamic adaptation to early pregnancy. To evaluate this, we studied mean arterial pressure (MAP) and heart rate (HR) in chronically instrumented, conscious rats in early (days 4, 6, 8, and 10) and late (day 18) pregnancy (n = 8) and in nonpregnant rats (n = 9). MAP and HR were recorded on a beat-to-beat basis and analyzed by spectral analysis. Spectral density power was calculated in low- (0.047-0.305 Hz), mid- (0.305-0.598 Hz), and high-frequency (0.598-1.494 Hz) bands, which contain oscillations that are among others related to myogenic-, sympathetic/vagal-, and vagal/respiration-related influences, respectively. In addition, baroreceptor reflex sensitivity was determined from spontaneous variations in MAP and HR by a sequential time series method and by calculating the transfer gain between MAP and HR in the midfrequency band. Mean values of HR and MAP did not differ between the two groups on day 4. In the pregnant group, MAP fell gradually over days, whereas HR had significantly increased only on day 18. Overall variability in MAP and HR (expressed as coefficients of variation) did not change during pregnancy. Baroreceptor reflex sensitivity did not differ between the groups and did not change with advancing pregnancy. Spontaneous oscillations of MAP and HR at low, mid, and high frequencies were not different between pregnant and nonpregnant rats on days 4 to 10. On day 18, spectral density power of MAP, but not of HR, in the high-frequency band had significantly increased in pregnant rats only, most likely reflecting the increased impact of breathing on MAP fluctuations. We conclude that, with the methods employed, we could not discern any changes in baroreflex sensitivity and MAP and HR variability in pregnancy. This would imply that changes in autonomic activity do not contribute appreciably to the hemodynamic adaptations in early rat pregnancy. PMID- 9362246 TI - Parasympathetic inhibition of sympathetic effects on atrioventricular conduction in anesthetized dogs. AB - To investigate the selective parasympathetic control of atrioventricular (AV) conduction during sympathetic activation, we studied the effects of cervical vagus nerve stimulation on the positive dromotropic responses to sympathetic interventions before and after surgical dissection of dual fatty tissues at the junction of the inferior vena cava and inferior left atrium and at the right atrial side of the atrial junctions of the right pulmonary veins in open-chest anesthetized dogs. In atrial-paced hearts, vagus stimulation at low frequencies prolonged atrio-His (A-H) interval and at high frequencies induced second- and third-degree AV blocks. Vagus stimulation additively prolonged A-H interval shortened by stimulation of the ansae subclaviae or isoproterenol infusion. After dissection of dual fatty tissues, vagus stimulation prolonged A-H interval by only 7%. However, during sympathetic stimulation but not during isoproterenol infusion, vagus stimulation prolonged the shortened A-H interval. Atropine abolished the responses to vagus stimulation. These results suggest that even during sympathetic activation, regional vagus inputs selectively control A-H interval, and even after denervation of the regional parasympathetic nerves, presynaptic parasympathetic inhibition of the positive cardiac responses to sympathetic activation works in the heart in situ. PMID- 9362247 TI - Role of neuronal NO synthase in relationship between NO and opioids in hypoxia induced pial artery dilation. AB - Nitric oxide (NO) contributes to hypoxia-induced pial artery dilation, at least in part, via the formation of guanosine 3',5'-cyclic monophosphate (cGMP) and subsequent release of Met-enkephalin and Leu-enkephalin in the newborn pig. In separate studies, these opioids were also observed to elicit NO-dependent pial dilation. The present study was designed to investigate the role of the neuronal isoform of NO synthase (NOS) in hypoxic pial dilation, associated opioid release, and opioid dilation in piglets equipped with a closed cranial window. Tetrodotoxin (10(-6) M) attenuated the dilation resulting from hypoxia (PO2 approximately 35 mmHg; 25 +/- 1 vs. 14 +/- 1%). Similarly, 7-nitroindazole, sodium salt (7-NINA, 10(-6) M), a purported neuronal NOS inhibitor, attenuated hypoxic pial dilation (26 +/- 1 vs. 14 +/- 2%). Hypoxic dilation was accompanied by elevated cerebrospinal (CSF) cGMP, which was blocked by 7-NINA (433 +/- 19 and 983 +/- 36 vs. 432 +/- 19 and 441 +/- 19 fmol/ml for control and hypoxia in absence and presence of 7-NINA, respectively). Additionally, hypoxic dilation was also accompanied by elevated CSF Met-enkephalin, which was attenuated by 7-NINA (1,027 +/- 47 and 2,871 +/- 134 vs. 779 +/- 78 and 1,551 +/- 42 pg/ml for control and hypoxia in absence and presence of 7-NINA, respectively). In contrast, Met enkephalin (10(-10), 10(-8), and 10(-6) M) induced dilation that was unchanged by 7-NINA (7 +/- 1, 12 +/- 1, and 18 +/- 1 vs. 6 +/- 1, 10 +/- 1, and 17 +/- 1%, respectively). N-methyl-D-aspartate (NMDA, 10(-8) and 10(-6) M), an activator of neuronal NOS, induced pial dilation that was blocked by 7-NINA (10 +/- 1 and 20 +/- 2 vs. 1 +/- 1 and 2 +/- 1%, respectively). However, sodium nitroprusside induced dilation was unchanged by 7-NINA. These data indicate that neuronal NOS contributes to hypoxic pial artery dilation but not to opioid-induced dilation. Furthermore, these data suggest that neuronally derived NO contributes to hypoxic dilation, at least in part, via formation of cGMP and the subsequent release of opioids. PMID- 9362248 TI - Endogenous nitric oxide on arterial hemodynamics: a comparison between normotensive and hypertensive rats. AB - Endogenous nitric oxide (NO) plays an important role in maintaining a vasodilator tone. In the present study, we compared the effects of NO blockade on the steady and pulsatile components of arterial hemodynamics between spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto strain (WKY), 22-26 wk of age. In the first series of experiments, various doses (1-30 mg/kg i.v.) of N(G) nitro-L-arginine methyl ester (L-NAME) were administered to block the NO release in anesthetized WKY and SHR. In both WKY and SHR, L-NAME caused a dose-dependent increase in arterial pressure (AP) with a decrease in heart rate (HR). The maximal effects of L-NAME on AP and HR occurred at a dose of 10 mg/kg. Both the AP increase and HR decrease were higher in SHR (AP, +38 +/- 4 mmHg; HR, -49 +/- 5 beats/min) than WKY (AP, +22 +/- 3 mmHg; HR, -33 +/- 5 beat/min). In other series, the technique of impedance spectral analysis was employed to investigate the effects of L-NAME (10 mg/kg i.v.) on the arterial hemodynamics. The aortic pressure and flow waves were recorded and subjected to Fourier transform for the analysis of impedance spectra. Both in WKY (n = 12) and in SHR (n = 12), L-NAME significantly increased AP and total peripheral resistance (TPR). The pulsatile and frequency-dependent hemodynamics including characteristic impedance, wave reflection, and ventricular work were only slightly altered. Despite higher resting values of AP and TPR in SHR (mean AP, 154 +/- 7 mmHg; mean TPR, 204 +/- 17 x 10(3) dyn x s x cm(-5)) than WKY (mean AP, 94 +/- 6 mmHg; mean TPR, 98 +/- 12 x 10(3) dyn x s x cm(-5)), the magnitudes of AP and TPR increments after NO blockade were significantly higher in SHR (AP, +37 +/- 3 mmHg; TPR, +124 +/- 16 x 10(3) dyn x s x cm(-5)) than in WKY (AP, +24 +/- 3 mmHg; TPR, +45 +/- 7 x 10(3) dyn x s x cm(-5)). The continuous formation of endogenous NO affects predominantly the AP and peripheral resistance in both WKY and SHR. The windkessel functions, such as impedance spectra, pulse-wave reflection, and ventricular work, are less affected after NO blockade. In addition, the effects of NO release on the AP and TPR appear to be enhanced in rats with established hypertension. PMID- 9362250 TI - Cytoskeleton modulates coupling between availability and activation of cardiac sodium channel. AB - The aim of this study was to investigate modulation of voltage-dependent steady state activation and availability from inactivation of the cardiac Na+ channel by the cytoskeleton. As an experimental approach, we used long-lasting monitoring [63 +/- 5 (SE) min] of the half-point potentials of the steady-state availability curve (V(1/2A)) and normalized conductance curve (V(1/2G)) in 116 rat ventricular cardiomyocytes by whole cell patch clamp at 22-24 degrees C. Both half-point potentials shifted in the negative direction with time as an exponentially saturating change, with the shift of V(1/2G) being smaller and faster. An F-actin disrupter, cytochalasin D (Cyto-D, 20 microM), accelerated the rate of the V(1/2A) shift but decreased the range of the V(1/2G) shift. An F-actin stabilizer, phalloidin (100 microM), temporarily (for 28.2 +/- 2.2 min, n = 15) prevented the V(1/2A) shift but did not influence the V(1/2G) shift. The best fit for the V(1/2G)-V(1/2A) relationship in untreated cells (1,021 data points measured in 51 cells) was a second-degree (2.06) power function. Cytoskeleton directed agents modified the relationship. In Cyto-D-treated cells, the V(1/2G) V(1/2A) relationship was shifted (by 2.5 mV) toward positive V(1/2G). On the contrary, a microtubule stabilizer, taxol (100 microM), shifted the relationship toward negative V(1/2G) (by 12.2 mV). We conclude that coupling between availability and activation is modulated by F-actin-based and microtubular cytoskeleton. PMID- 9362249 TI - Dose-dependent effect of ANG II-receptor antagonist on myocyte remodeling in rat cardiac hypertrophy. AB - The goal of this study was to examine the effect of an angiotensin II type 1 (AT1)-receptor antagonist (TCV-116) on left ventricular (LV) geometry and function during the development of pressure-overload LV hypertrophy. A low (LD; 0.3 mg x kg(-1) x day(-1)) or a high (HD; 3.0 mg x kg(-1) x day(-1)) dose of TCV 116 was administered to abdominal aortic-banded rats over 4 wk, and hemodynamics and morphology were then evaluated. In both LD and HD groups, peak LV pressures were decreased to a similar extent compared with the vehicle-treated group but stayed at higher levels than in the sham-operated group. In the LD group, both end-diastolic wall thickness (3.08 +/- 0.14 mm) and myocyte width (13.3 +/- 0.1 microm) decreased compared with those in the vehicle-treated group (3.67 +/- 0.19 mm and 15.3 +/- 0.1 microm, respectively; both P < 0.05). In the HD group, myocyte length was further decreased (HD: 82.6 +/- 2.6, LD: 94.1 +/- 2.9 microm; P < 0.05) in association with a reduction in LV midwall radius (HD: 3.36 +/- 0.12, LD: 3.60 +/- 0.14 mm; P < 0.05) and peak midwall fiber stress (HD: 69 +/- 8, LD: 83 +/- 10 x 10(3) dyn/cm2; P < 0.05). There was no significant difference in cardiac output among all groups. The AT1-receptor antagonist TCV-116 induced an inhibition of the development of pressure-overload hypertrophy. Morphologically, not only the width but also the length of myocytes was attenuated with TCV-116, leading to a reduction of midwall radius and hence wall stress, which in turn may contribute to a preservation of cardiac output. PMID- 9362251 TI - Estimating a cardiac age by means of heart rate variability. AB - A data set of R-R intervals recorded for at least 15 min in 141 healthy individuals of different ages and under two different conditions ("resting" and "tilted" states) has been considered. The data have been subjected to spectral analysis by fast Fourier transform methods and considered in view of the possibility to work out a model in which the chronological and cardiac age could be compared. Understanding the results was greatly facilitated by 1) working out a number of derived variables from the original ones to highlight the presence of small but conceptually important variability factors; 2) extraction of the principal components from the original as well as from the derived variables to exclude redundancies and correlation effects; and 3) automatic clustering of the subjects in age classes, which allowed removal of individual variability within each class. The main conclusion is that, within the examined individuals, cardiac and chronological ages do not match for ages higher than approximately 50 years; this could reflect the presence of subtle (and difficult-to-envisage) biases in the data analysis or a real discrepancy. The latter hypothesis should be confirmed by similar observations in different systemic contexts. The use of a simple equation relating chronological and cardiac age, derived from a careful regression analysis on our data set and of general use for screening purposes, is demonstrated. PMID- 9362252 TI - Components of acetylcholine-induced dilation in isolated rat arterioles. AB - Acetylcholine-induced dilation was studied in cannulated resistance arteries of rat cremaster muscle. Pressurized arteriolar segments (internal diameter: 175 +/- 2 microm) developed spontaneous tone (90 +/- 2 microm). Application of acetylcholine (0.1 and 0.3 microM) resulted in a transient dilation followed by a steady-state dilatory response. In the presence of N(G)-nitro-L-arginine (L-NNA) approximately 70% of the transient dilation was resistant to nitric oxide inhibition, whereas the steady-state response was abolished. Further experiments using 0.1 microM acetylcholine (no L-NNA present) were aimed to inhibit synthesis or action of the mediator of the transient component (amplitude: 39 +/- 2.8 microm). A high-potassium buffer (30-50 mM) abolished this transient dilation (1.3 +/- 1.3 microm), suggesting that the dilation is mediated by an endothelium derived hyperpolarizing factor (EDHF). This putative EDHF-mediated dilation is strongly reduced by cytochrome P-450 inhibitors miconazole (11 +/- 1.3 microm) and SKF-525a (4.8 +/- 4.5 microm). The transient component is inhibited by tetraethylammonium but not by glibenclamide, indicating it is mediated by opening of Ca2+-activated K+ channels. Interestingly, inhibition of the transient component was followed by a subsequent decrease of the nitric oxide-mediated part of the response to acetylcholine. Thus a transient dilation, mediated by a cytochrome P-450 metabolite, precedes and possibly stimulates nitric oxide mediated dilation in acetylcholine-induced dilation. PMID- 9362253 TI - Cyclooxygenase inhibition decreases nitric oxide synthase activity in human platelets. AB - Activity of both nitric oxide (NO) synthase (NOS) and cyclooxygenase (COX) plays an important role in the regulation of platelet function. NO has been shown to directly activate COX. This study was designed to determine whether products of the COX pathway in turn regulate NOS activity. Human platelets were incubated with aspirin, indomethacin, the selective thromboxane A2 synthase inhibitor U 63557A, or the prostaglandin H2-thromboxane A2-receptor blocker SQ-29548 for 1 h at 37 degrees C. Multiple indexes of the activity of the L-arginine-NO pathway and changes in cytosolic Ca2+ concentration ([Ca2+]i) were measured in platelets. Both aspirin and indomethacin decreased NOS activity, measured as the conversion of L-arginine to L-citrulline and nitrite (+nitrate) formation, in platelets in a concentration-dependent fashion. Aspirin also decreased guanosine 3',5'-cyclic monophosphate accumulation in platelets. The NOS inhibitory effects of these aspirin and indomethacin effects were reversed by coincubation with the thromboxane A2 analog U-46619 or an excess of CaCl2. Incubation of COX inhibitors with platelets was associated with significant reductions in basal as well as thrombin-stimulated [Ca2+]i, and the reduction in [Ca2+]i was reversed by U 46619. Incubation of platelets with U-63557A and SQ-29548 resulted in inhibitory effects on NOS activity qualitatively similar to those of COX inhibitors. The effects of COX inhibitors or U-63557A were not associated with a change in NOS protein expression in platelets. These data suggest that NOS activity in human platelets is inhibited by COX inhibitors, mediated, at least in part, via suppression of thromboxane A2 and [Ca2+]i mobilization in platelets. PMID- 9362254 TI - Ischemic preconditioning triggers phospholipase D signaling in rat heart. AB - Recent studies have indicated that repeated brief episodes of ischemia and reperfusion render the myocardium more tolerant to subsequent lethal ischemic injury. In view of the previous observations that ischemia-reperfusion potentiates phospholipase D signaling and that such signaling is beneficial for the heart, we investigated whether a similar phospholipase D signaling is responsible for the beneficial effects associated with repeated ischemia and reperfusion. Using an isolated perfused working rat heart model, we demonstrated that four brief episodes of 5 min of ischemia and 10 min of reperfusion reduced the incidence of ventricular arrhythmias, enhanced the postischemic ventricular performance, and decreased the release of creatine kinase from the reperfused heart, with simultaneous activation of phospholipase D generating the second messengers diacylglycerol and phosphatidic acid and leading to the translocation and activation of protein kinase C. The specific antiphospholipase D antibody blocked the activation of phospholipase D and attenuated the generation of diacylglycerol and phosphatidic acid and activation of protein kinase C. In concert, phospholipase D inhibition increased the incidence of ventricular arrhythmias, blocked the beneficial effects of preconditioning on the ventricular performance, and increased the amount of creatine kinase release from the coronary effluent. The results of this study indicate that repeated brief episodes of ischemia and reperfusion exert beneficial effects on the intact rat heart by triggering the activation of a phospholipase D signaling mechanism. PMID- 9362255 TI - Synchronous and baroceptor-sensitive oscillations in skin microcirculation: evidence for central autonomic control. AB - To determine whether skin blood flow is local or takes part in general regulatory mechanisms, we recorded laser-Doppler flowmetry (LDF; left and right index fingers), blood pressure, muscle sympathetic nerve activity (MSNA), R-R interval, and respiration in 10 healthy volunteers and 3 subjects after sympathectomy. We evaluated 1) the synchronism of LDF fluctuations in two index fingers, 2) the relationship with autonomically mediated fluctuations in other signals, and 3) the LDF ability to respond to arterial baroreflex stimulation (by neck suction at frequencies from 0.02 to 0.20 Hz), using spectral analysis (autoregressive uni- and bivariate, time-variant algorithms). Synchronous LDF fluctuations were observed in the index fingers of healthy subjects but not in sympathectomized patients. LDF fluctuations were coherent with those obtained for blood pressure, MSNA, and R-R interval. LDF fluctuations were leading blood pressure in the low frequency (LF; 0.1 Hz) band and lagging in the respiratory, high-frequency (HF; approximately 0.25 Hz) band, suggesting passive "downstream" transmission only for HF and "upstream" transmission for LF from the microvessels. LDF fluctuations were responsive to sinusoidal neck suction up to 0.1 Hz, indicating response to sympathetic modulation. Skin blood flow thus reflects modifications determined by autonomic activity, detectable by frequency analysis of spontaneous fluctuations. PMID- 9362256 TI - Altered reactivity of coronary arteries located distal to a chronic coronary occlusion. AB - The coronary vasculature located distal to a chronic occlusion (collateral dependent) has been shown to exhibit altered reactivity to vasoactive agonists. Thus we evaluated effects of chronic coronary artery occlusion on vasomotor responsiveness of collateral-dependent arteries isolated from a canine model of Ameroid occlusion of the left circumflex (LCX) coronary artery. We compared in vitro responses of large (approximately 1.3- to 1.4-mm-ID) and small (approximately 0.6-mm-ID) LCX arteries located distal to an occlusion with responses of similar-sized segments of the unoccluded left anterior descending (LAD) coronary artery. Alpha-adrenergic receptor-mediated contractile responses to norepinephrine (10(-9)-10(-4) M) and phenylephine (10(-9)-10(-4) M) in the presence of propranolol were markedly enhanced in large LCX arteries compared with LAD arteries (P < 0.001). Prazosin (1 microM), an alpha1-adrenergic receptor antagonist, abolished contractile responses of LCX and LAD arteries to norepinephrine. Inhibition of nitric oxide synthesis with N(omega)-nitro-L arginine methyl ester (100 microM) enhanced norepinephrine-induced contractions of LAD arteries to a greater extent than contractions of LCX arteries. We simultaneously measured myoplasmic free Ca2+ (fura 2 fluorescence ratio) and contractile responses in LCX and LAD arteries denuded of endothelium; norepinephrine-induced increases in myoplasmic free Ca2+ and contractile tension were significantly enhanced in LCX arteries compared with LAD arteries. In addition, large and small LCX arteries exhibited impaired relaxation in response to adenosine (10(-8)-10(-3) M) compared with LAD arteries (P < 0.05). In contrast, relaxation in response to the beta-adrenergic agonist isoproterenol (10(-9)-10(-4) M) and sodium nitroprusside (10(-10)-10(-4) M) was not significantly different in LCX and LAD arteries. Thus collateral-dependent coronary arteries exhibit enhanced alpha-adrenergic vasoconstriction and impaired vasorelaxation in response to adenosine. The enhanced alpha-adrenergic contractile responsiveness involves at least two mechanisms: 1) enhanced alpha1 adrenergic reactivity of smooth muscle and 2) decreased alpha-adrenergic-induced synthesis of nitric oxide by the endothelium. PMID- 9362257 TI - Diabetes with and without ketoacidosis on right atrial pacemaker rate and autonomic responsiveness. AB - Experiments were designed to determine whether insulin-dependent diabetes mellitus (IDDM) alters direct chronotropic effects of adrenergic and cholinergic agonists and whether the observed changes are associated with hyperglycemia or combined hyperglycemia and ketoacidosis. Diabetes was induced by intravenous administration of 45, 50, or 65 mg/kg streptozotocin (STZ). Rats treated with 65 mg/kg STZ had higher levels of blood glucose and ketones compared with the levels of the other groups. Right atria were isolated 12 wk after administration of STZ and bathed in Krebs-Henseleit solution. Basal spontaneous pacemaker rate was diminished in preparations isolated from diabetic rats. The maximum pacemaker rate observed during exposure to isoproterenol or norepinephrine was also depressed in preparations from diabetic animals; however, the increase in rate and half-maximal effective concentration values for each agent were not affected. The sensitivity to the negative chronotropic action of acetylcholine was enhanced by IDDM, whereas the response to carbachol (a cholinergic agonist not readily metabolized by acetylcholinesterase) was not changed. No significant differences were observed when we compared preparations isolated from diabetic animals with and without ketoacidosis. In summary, these data suggest 1) that IDDM is associated with a diminished basal spontaneous pacemaker without changes in the responsiveness to adrenergic and cholinergic receptor activation and 2) that ketoacidosis does not play a role in the observed alterations. PMID- 9362259 TI - Endothelial cell adhesion molecule expression in gene-targeted mice. AB - Gene-targeted mice are now routinely employed as tools for defining the contribution of different leukocyte and endothelial cell adhesion molecules to the leukocyte recruitment and tissue injury associated with acute and chronic inflammation. The objective of this study was to determine whether gene-targeted mice that are deficient in CD11/CD18, intracellular adhesion molecule-1 (ICAM-1), or P-selectin exhibit an altered constitutive or induced expression of the endothelial cell adhesion molecules E- and P-selectin. The gene-targeted mice were all developed in the 129Sv mouse strain and backcrossed into C57B1/6J mice. The number of backcrosses ranged between 8 (P-selectin) and 10 (CD18 and ICAM-1) generations. The dual-radiolabeled monoclonal antibody technique was used to quantify E- and P-selectin expression in different vascular beds. In the unstimulated state, E-selectin expression was significantly elevated (relative to wild-type mice) in the stomach, large intestine, and brain of mutants deficient in ICAM-1. In general, constitutive expression of P-selectin did not differ between wild-type, ICAM-1-deficient, and CD11/CD18-deficient mutants. In CD11/CD18-deficient mice, tumor necrosis factor-alpha (TNF-alpha) administration elicited a more profound upregulation of P-selectin in several vascular beds, compared with wild-type and ICAM-1-deficient mice. E-selectin expression in brain of TNF-alpha-stimulated, ICAM-1-deficient, and P-selectin-deficient mice was attenuated compared with wild-type mice. These findings indicate that chronic deficiency of some of the adhesion glycoproteins that mediate leukocyte recruitment alters basal and induced surface expression of other adhesion molecules on endothelial cells. PMID- 9362258 TI - LPS induces late cardiac functional protection against ischemia independent of cardiac and circulating TNF-alpha. AB - Lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-alpha independently induce cardioprotection against ischemia in the rat at 24 h after administration, suggesting that endogenously synthesized TNF-alpha may play a role in LPS-induced protection. The purposes of this study were 1) to delineate the time course of LPS-induced cardiac functional protection against ischemia and its relation with myocardial and circulating TNF-alpha profile, 2) to examine whether prior protein synthesis inhibition abrogates the protection, and 3) to assess the effects of TNF-alpha inhibition and neutralization on the protection. Rats were treated with LPS (0.5 mg/kg i.p.). Cardiac functional resistance to normothermic global ischemia-reperfusion was examined at sequential time points after LPS treatment in isolated hearts by the Langendorff technique. Myocardial and circulating TNF alpha was determined by enzyme-linked immunosorbent assay at 1-24 h after LPS treatment. Protection was apparent at 24 h, 3 days, and 7 days but not at 2 or 12 h. Maximal protection at 3 days was abolished by cycloheximide pretreatment (0.5 mg/kg i.p. 3 h before LPS treatment). Increases in myocardial and circulating TNF alpha preceded the acquisition of protection. Dexamethasone pretreatment (4.0 or 8.0 mg/kg i.p. 30 min before LPS treatment) abolished peak increase in myocardial TNF-alpha and substantially suppressed circulating TNF-alpha (54.3 and 85.9% inhibition, respectively) without an influence on the maximal protection. Similarly, maximal protection was not affected by TNF binding protein (40 or 80 microg/kg i.v. immediately after LPS treatment). The results suggest that LPS induced cardiac functional protection against ischemia is a delayed and long lasting protective response that may involve de novo protein synthesis. Although LPS-induced increase in myocardial and circulating TNF-alpha precedes the delayed protection, it may not be required for the delayed protection. PMID- 9362260 TI - Pontine neurons are elements of the network responsible for the 10-Hz rhythm in sympathetic nerve discharge. AB - The current study was designed to test the hypothesis that pontine neurons are elements of the network responsible for the 10-Hz rhythm in sympathetic nerve discharge (SND). The first series of experiments tested whether chemical inactivation of neurons in the rostral dorsolateral pons (RDLP) or caudal ventrolateral pons (CVLP) affected inferior cardiac postganglionic SND of urethan anesthetized cats. Muscimol microinjections into either region eliminated the 10 Hz rhythm in SND, supporting the view that pontine neurons are involved in the expression of this rhythm. Additional experiments were designed to determine if pontine neurons have activity correlated to the 10-Hz rhythm in SND or whether they merely provide a tonic (nonrhythmic) driving input to the rhythm generator. Coherence analysis revealed that local field potentials recorded from the RDLP or CVLP had a 10-Hz component that was significantly correlated to SND. Also, spike triggered averaging and coherence analysis showed that the naturally occuring discharges of individual RDLP or CVLP neurons were correlated to the 10-Hz rhythm in SND. Taken together, these data support the hypothesis that RDLP and CVLP neurons are essential for the expression of the 10-Hz rhythm in SND and that they are elements of or receive input from the rhythm generator. PMID- 9362261 TI - c-Ha-rasEJ transfection in vascular smooth muscle cells circumvents PKC requirement during mitogenic signaling. AB - In view of the prominent role of protein kinase C (PKC) in the regulation of vascular smooth muscle cell (VSMC) growth and differentiation, the present studies were conducted to assess the impact of c-Ha-rasEJ transfection on PKC dependent growth programming. PKC activity was elevated in the cytosolic and particulate compartments of c-Ha-rasEJ VSMC, relative to naive or pSV2neo vector controls. Constitutive and 12-O-tetradecanoyl phorbol 13-acetate (TPA)-inducible binding to a TPA-responsive element (TRE) was also enhanced in c-Ha-rasEJ VSMC. Fetal bovine serum (FBS) did not increase TRE-binding activity in serum-starved c Ha-rasEJ VSMC but increased TRE-binding activity in pSV2neo VSMC. FBS-mediated TRE-binding activity was dramatically decreased in serum-starved pSV2neo VSMC pretreated with 100 ng/ml TPA for 24 h to downregulate PKC activity. c-Ha-rasEJ VSMC exhibited a marked proliferative advantage over controls under both restrictive and growth-permissive serum conditions. PKC downregulation did not influence the mitogenic response to serum in c-Ha-rasEJ VSMC but ablated [3H]thymidine incorporation into DNA in naive or pSV2neo vector counterparts. Western blot analysis demonstrated increased expression of extracellular signal regulated kinase 2 (ERK2), but not ERK1, in c-Ha-rasEJ VSMC, relative to pSV2neo control. Immunoblots of serum-starved and PKC-depleted c-Ha-rasEJ VSMC demonstrated a dramatic increase in the phosphorylated form of ERK2, relative to pSV2neo controls. These data suggest that oncogenic c-Ha-rasEJ circumvents a requirement for a TPA-responsive PKC isoform(s) during mitogenic stimulation of VSMC. PMID- 9362263 TI - Positive chronotropic and inotropic effects of C-type natriuretic peptide in dogs. AB - We have recently reported that C-type natriuretic peptide (CNP) has a positive chronotropic effect in dogs. We further investigated the effect of CNP on canine cardiac functions: 1) in situ, by exploring the effects of isoproterenol (10 microg), angiotensin II (ANG II, 5 microg), and CNP (40 microg) injections (n = 8) on computerized epicardial mapping of atrial activation to detect a shift in pacemaker location; 2) by examining the presence of natriuretic peptide receptor (NPR)-A and -B mRNAs in atrial and nodal tissues using semiquantitative reverse transcription polymerase chain reaction; 3) in vitro, using spontaneously beating right atrial preparations (n = 6), by recording the transmembrane potentials of sinoatrial node (SAN) cells before and after injection of CNP (25 microg); and 4) by observing the effects of CNP (25 microg) on contractile force of paced isolated right atrial preparations (n = 6). The results indicate that 1) the site of earliest extracellular electrical activation in the SAN remains mostly unchanged in response to CNP, whereas it shifts to the superior region of the SAN after isoproterenol and ANG II injections; 2) NPR-A and -B mRNAs are present in atrial and nodal tissues; 3) CNP significantly increases the maximal rate of diastolic depolarization and decreases the action potential duration at 75 and 90% of repolarization; and 4) CNP significantly increases atrial contractile force. These results suggest that CNP modifies cardiac ionic currents to produce positive chronotropic and inotropic effects by stimulation of NPR-B receptors, located in the SAN region, and that CNP plays a role in the modulation of cardiac function. PMID- 9362262 TI - Role of AVP in pressor responses during activation of central TxA2/PGH2 receptors. AB - Administration of thromboxane A2/prostaglandin H2 (TxA2/PGH2)-receptor agonist U 46619 (2.86 nmol/kg i.v.) to conscious rats increased mean arterial pressure (MAP) by 17 +/- 2 mmHg (n = 6; P < 0.001) and plasma arginine vasopressin (AVP) by 3.5 +/- 1.1 IU/ml (n = 6; P < 0.001). Ifetroban (TxA2/PGH2 antagonist; intracerebroventricularly) prevented both responses. Intracerebroventricular U 46619 increased MAP in Long-Evans rats (n = 6) more than in AVP-deficient Brattleboro rats. AVP V1-receptor antagonist d(CH2)5Tyr(Me)AVP (3 microg/kg i.v.) blocked 67 +/- 5% and 69 +/- 7% of pressor response to intravenous AVP and intracerebroventricular U-46619, respectively. AVP (10 ng/kg i.v.) increased AVP by 4.7 +/- 0.5 pg/ml, comparable to the increase of 3.5 +/- 1.2 pg/ml with intracerebroventricular U-46619 (2.86 nmol/kg), but the rise in MAP was only one half as great (+8 +/- 3 mmHg for AVP vs. +17 +/- 2 mmHg for U-46619; P < 0.05). In conclusion, U-46619 raises blood pressure and releases AVP by activating brain receptors. AVP explains approximately one-half of the pressor response. PMID- 9362264 TI - Circulating and cellular markers of endothelial dysfunction with aging in rats. AB - The influence of age on endothelial functional markers was investigated in rats. Angiotensin I converting enzyme (ACE) activity and nitric oxide synthase (NOS) mRNA expressions were examined in the lung and aorta of 10-, 20-, and 30-mo-old normotensive rats. These data were extended by the measurement of circulating endothelial cells. ACE activity was significantly decreased in plasma (P < 0.01) and lungs (P < 0.01) at 30 mo, whereas it was significantly increased in the aorta (P < 0.001) at this age. Conversely, ACE mRNA levels decreased with age in the lung (P < 0.05). The level of constitutive endothelial NOS (eNOS) mRNA was significantly reduced in the aorta of 30-mo-old rats (P < 0.05), but no changes were observed in the lungs. The level of inducible NOS (iNOS) mRNA in the aorta was significantly decreased in 20- and 30-mo-old rats (P < 0.01), whereas it was significantly increased in the lung at 30 mo (P < 0.01). Interestingly, eNOS was expressed approximately 30 times more (P < 0.001) in the aorta than iNOS, whereas in the lung it was only slightly higher than iNOS (35%; P < 0.001). Neuronal NOS mRNA expression was not modified with aging. In the aorta, guanosine 3',5'-cyclic monophosphate concentration followed NOS expressions and showed a significant decrease at 30 mo (P < 0.001). An increase in the number of circulating endothelial cells was observed in the oldest rats, possibly reflecting an increase in endothelial cell turnover with aging. The present results demonstrate that aging modifies the expression of endothelial markers implicated in the regulation of vasomotor tone. This age-dependent impairment of endothelial functions could contribute to the increased risk of pathological processes within the arterial wall associated with aging. PMID- 9362266 TI - Taurine depletion, a novel mechanism for cardioprotection from regional ischemia. AB - Three processes that have been implicated in ischemic injury are impaired Ca2+ movement, altered osmoregulation, and membrane remodeling. Because the amino acid, taurine, affects all three processes, it seemed logical that changes in the myocardial content of taurine might affect ischemic injury. To test this hypothesis, infarct size and areas at risk were compared in isolated hearts from control and taurine-depleted rats after a 45-min ligation of the left anterior descending coronary artery and 2 h of reperfusion. Hearts of rats treated for 4 wk with the taurine inhibitor, beta-alanine, exhibited a 57% reduction in the infarct size-to-risk area ratio. The degree of cardioprotection was found to correlate (r = 0.85) with the extent of taurine depletion, the latter dependent on the length of beta-alanine feeding. When the taurine-depleted rats were fed taurine, myocardial taurine levels were restored and the cardioprotection was lost. However, addition of neither beta-alanine (3%) nor taurine (20 mM) to the perfusion medium altered infarct size. We conclude that taurine depletion renders the heart resistant to injury caused by regional ischemia. PMID- 9362265 TI - cGMP level that reduces cardiac myocyte O2 consumption is altered in renal hypertension. AB - We tested the hypothesis that cardiac myocytes from hypertensive (one kidney, one clip; 1K,1C) cardiac-hypertrophied rabbits require higher guanosine 3',5'-cyclic monophosphate (cGMP) to similarly lower O2 consumption than control myocytes and that this effect is caused by differences in guanylate cyclase activity. Using isolated myocytes from control and 1K,1C New Zealand White rabbits, we obtained O2 consumption (nl O2 x min(-1) x 10(5) cells) and cGMP (fmol/10(5) cells) levels after stimulation of guanylate cyclase with nitroprusside, CO, or guanylin (10( 8)-10(-5) M). Soluble guanylate cyclase activity was also determined. Basal cGMP was elevated in 1K,1C vs. control (176 +/- 28 vs. 85 +/- 13) myocytes. cGMP increased in 1K,1C and control myocytes after stimulation with nitroprusside, CO, and guanylin. Guanylate cyclase activity in 1K,1C vs. control myocytes was not statistically different. Basal O2 consumption in 1K,1C vs. control myocytes was comparable (307 +/- 1 vs. 299 +/- 22). O2 consumption was similarly decreased when guanylate cyclase was stimulated. Control regression equations correlating cGMP and O2 consumption were O2 consumption = -1.46 x [cGMP] + 444.65 (r = 0.96) for CO, O2 consumption = -0.58 x [cGMP] + 328.48 (r = 0.82) for nitroprusside, and O2 consumption = -1.25 x [cGMP] + 389.15 (r = 0.88) for guanylin. The 1K,1C regression equations were O2 consumption = -1.36 x [cGMP] + 537.81 (r = 0.97) for CO, O2 consumption = -0.23 x [cGMP] + 307.30 (r = 0.88) for nitroprusside, and O2 consumption = -1.27 x [cGMP] + 502.91 (r = 0.89) for guanylin. These data indicate that 1K,1C hypertrophic myocytes had higher cGMP than controls at every level of O2 consumption. This effect was not caused by differences in basal or maximal guanylate cyclase activity. PMID- 9362267 TI - Gender and transcriptional regulation of NO synthase and ET-1 in porcine aortic endothelial cells. AB - Experiments were designed to determine whether normal fluctuations in sex steroid hormones alter gene transcription for endothelial nitric oxide synthase (NOS) and preproendothelin-1 (prepro-ET-1). Aortic endothelial cells were removed from adult, gonadally intact male and female or ovariectomized Yorkshire pigs. Endothelial cells were prepared for Northern blot analysis, Western blot analysis or enzyme activity. Nitric oxide products (NOx) and endothelin-1 (ET-1) in plasma were measured by chemiluminescence and radioimmunoassay, respectively. Northern blot analysis identified single bands corresponding to endothelial NOS and prepro ET-1. Quantification of the blots showed an increase in expression of mRNA for both endothelial NOS and prepro-ET-1 in ovariectomized pigs compared with gonadally intact male and female pigs. There were no differences in amount of endothelial NOS protein identified by Western blot analysis among groups. On the contrary, plasma concentrations of NOx were significantly decreased in ovariectomized pigs, and there were no differences either in the concentrations of ET-1 in the plasma or extracts from the coronary arteries. These results suggest that expression of endothelial NOS and prepro-ET-1 may be regulated at transcriptional level by ovarian hormones. In addition, the ovarian hormones may regulate production of these endothelium-derived factors at the posttranscriptional level. PMID- 9362269 TI - Expression of adenine nucleotide translocator parallels maturation of respiratory control in heart in vivo. AB - Changes in the relationship between myocardial high-energy phosphates and oxygen consumption in vivo occur during development, implying that the mode of respiratory control undergoes maturation. We hypothesized that these maturational changes in sheep heart are paralleled by alterations in the adenine nucleotide translocator (ANT), which are in turn related to changes in the expression of this gene. Increases in myocardial oxygen consumption (MVO2) were induced by epinephrine infusion in newborn (0-32 h, n = 6) and mature sheep (30-32 days, n = 6), and high-energy phosphates were monitored with 31P nuclear magnetic resonance. Western blot analyses for the ANT1 and the beta-subunit of F1 adenosinetriphosphatase (ATPase) were performed in these hearts and additional (n = 9 total per group) as well as in fetal hearts (130-132 days of gestation, n = 5). Northern blot analyses were performed to assess for changes in steady-state RNA transcripts for these two genes. Kinetic analyses for the 31P spectra data revealed that the ADP-MVO2 relationship for the newborns conformed to a Michaelis Menten model but that the mature data did not conform to first- or second-order kinetic control of respiration through ANT. Maturation from fetal to mature was accompanied by a 2.5-fold increase in ANT protein (by Western blot), with no detectable change in beta-F1-ATPase. Northern blot data show that steady-state mRNA levels for ANT and beta-F1-ATPase increased approximately 2.5-fold from fetal to mature. These data indicate that 1) respiratory control pattern in the newborn is consistent with a kinetic type regulation through ANT, 2) maturational decreases in control through ANT are paralleled by specific increases in ANT content, and 3) regulation of these changes in ANT may be related to increases in steady-state transcript levels for its gene. PMID- 9362268 TI - Three-dimensional residual strain in midanterior canine left ventricle. AB - All previous studies of residual strain in the ventricular wall have been based on one- or two-dimensional measurements. Transmural distributions of three dimensional (3-D) residual strains were measured by biplane radiography of columns of lead beads implanted in the midanterior free wall of the canine left ventricle (LV). 3-D bead coordinates were reconstructed with the isolated arrested LV in the zero-pressure state and again after local residual stress had been relieved by excising a transmural block of tissue. Nonhomogeneous 3-D residual strains were computed by finite element analysis. Mean +/- SD (n = 8) circumferential residual strain indicated that the intact unloaded myocardium was prestretched at the epicardium (0.07 +/- 0.06) and compressed in the subendocardium (-0.04 +/- 0.05). Small but significant longitudinal shortening and torsional shear residual strains were also measured. Residual fiber strain was tensile at the epicardium (0.05 +/- 0.06) and compressive in the subendocardium (-0.01 +/- 0.04), with residual extension and shortening, respectively, along structural axes parallel and perpendicular to the laminar myocardial sheets. Relatively small residual shear strains with respect to the myofiber sheets suggest that prestretching in the plane of the myocardial laminae may be a primary mechanism of residual stress in the LV. PMID- 9362270 TI - Carbachol promotes Na+ entry and augments Na/Ca exchange current in guinea pig ventricular myocytes. AB - The effect of carbachol (CCh) on the Na/Ca exchange current (I(Na/Ca)) was studied in voltage-clamped ventricular myocytes isolated from guinea pig hearts and superfused with Tyrode solution at 35 degrees C. CCh (100 microM) increased outward current during depolarizations (10-200 ms) from -45 mV and tail current amplitude on repolarization; CCh had no effect on the L-type Ca2+ current. Amplitudes of the outward and tail currents declined with increasing duration of the depolarizing clamp pulse. Ouabain produced similar current changes that are suppressed by intrapipette ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N' tetraacetic acid and are characteristic of I(Na/Ca). Depolarization from -80 to 30 mV elicited the rapid Na+ current followed by a slowly decaying inward I(Na/Ca) (J. C. Gilbert, T. Shirayama, and A. J. Pappano. Circ. Res. 69: 1632 1639, 1991.) that was reversibly increased by CCh. Atropine (1-3 microM) prevented the CCh effect. All procedures that suppressed I(Na/Ca) also suppressed the CCh effect. Sarcoplasmic reticulum (SR) Ca2+ release participated in generating I(Na/Ca) because 10 mM caffeine or 1 microM ryanodine blocked I(Na/Ca) and the effect of CCh. Rapid superfusion of 10 mM caffeine induced inward I(Na/Ca) at -75 mV; a caffeine-induced charge transfer gives an SR Ca2+ content of 67 microM. CCh increased caffeine-induced current; SR Ca2+ content rose to 98 microM. CCh also augmented the amplitude of steady-state intracellular Ca2+ transients and contractions during a train of voltage-clamp pulses (-75 to 30 mV for 200 ms) at 1 Hz. CCh elevated intracellular Na+ (M. Korth and V. Kuhlkamp. Pflugers Arch. 403: 266-272, 1985) by inducing a background Na+ current [K. Matsumoto and A. J. Pappano. J. Physiol. (Lond.) 415: 487-502, 1989]. Together with these data, the present results are consistent with the hypothesis that CCh, via muscarinic receptors, eventually promotes I(Na/Ca) at the sarcolemma through a mechanism that requires the SR and that this action accounts for the increased contractions. PMID- 9362271 TI - NO contributes to neurohypophysial but not other regional cerebral fluorocarbon induced hyperemia in cats. AB - The large increase in cerebral blood flow (CBF) after fluorocarbon (FC)-exchange transfusion is thought to be caused by low oxygen content, decreased viscosity, or direct vasodilatory effect of the FC perfusate. The aim of this study was to determine whether nitric oxide (NO)-mediated vasorelaxation is increased in FC perfused hemoglobin (Hb)-free cats because NO is not scavenged by Hb. We measured regional CBF with radiolabeled microspheres in three groups of anesthetized mechanically ventilated cats. The first group [FC + N(omega)-nitro-L-arginine methyl ester (L-NAME), n = 7] underwent a complete FC-exchange transfusion with FC-43 and subsequent nitric oxide synthase (NOS) inhibition with L-NAME (10 mg/kg i.v.) followed by L-arginine (100 mg/kg i.v.). A second group (FC + saline; n = 6) underwent an identical protocol, but NOS was not antagonized (saline i.v.). In a third group (blood + L-NAME; n = 7), cats were not FC exchanged but NOS was inhibited. In a separate cohort of four FC-perfused cats, NOS activity in brain tissue samples was reduced to 26% of control after NOS inhibition. FC-exchange transfusion nearly doubled hemispheric blood flow in both FC-exchanged groups, whereas it was constant in the blood + L-NAME group. These increases in regional CBF (hemispheres, brain stem, cerebellum, thalamus, and white matter) were not reversed by inhibition of NOS, except in the neurohypophysis, where L-NAME reduced blood flow to levels comparable to values in the blood + L-NAME group. In summary, increases in regional CBF after total FC-exchange transfusion are not caused by a lack of NO scavenging, with the exception of neurohypophysis. These findings suggest an increased vasorelaxation in neurohypophysis of FC-perfused and Hb-free cats caused by unscavenged NO, but this mechanism does not play a major role in FC-related CBF increases in the rest of the cerebral circulation. PMID- 9362272 TI - Cerebral circulatory responses of near-term ovine fetuses during sustained fetal placental embolization. AB - To test the hypothesis that, in response to an increase in placental vascular resistance and progressive fetal asphyxia, the changes in external carotid blood flow waveforms are directly related to changes in external carotid vascular resistance, we embolized the fetal side of the placenta in pregnant sheep and measured cerebral and external carotid artery circulatory changes in relation to changes in external carotid artery flow waveforms. Chronically catheterized fetal sheep at 0.85 of gestation were embolized (n = 11) in the descending aorta for 6 h, until fetal arterial pH fell to approximately 6.90. Fetuses became rapidly hypoxemic (P < 0.0001) and developed a mixed respiratory and metabolic acidosis (P < 0.0001 for PCO2, pH, and base excess). There was a transient 40% increase in external carotid blood flow at pH approximately 7.25 and a parallel 32% increase in fetal arterial blood pressure (both (P < 0.01), whereas the external vascular resistance remained unaltered. Cerebral blood flow increased by 130% (P < 0.0001), and cerebral vascular resistance decreased by 125% (P < 0.0001) throughout the study. The external carotid resistance index (RI) decreased by 32% (P < 0.0001) at the time external carotid vascular resistance remained unchanged. This fall in external carotid RI was due almost entirely to a 110% increase in external carotid fundamental impedance (P < 0.001). We conclude that the poor relationship between the changes in external carotid vascular resistance and RI indicated that other hemodynamic factors such as vascular impedance to pulsatile flow must be measured for correct interpretation of changes in flow waveform shape under hypoxic conditions. In addition, changes in external carotid blood flow were not proportional to changes in cerebral blood flow in this model. PMID- 9362273 TI - Regulation of endometrial blood flow in ovariectomized rats: assessment of the role of nitric oxide. AB - The purpose of this study was to evaluate the role of nitric oxide (NO) in the maintenance of basal endometrial blood flow of ovariectomized rats and in the increase of endometrial blood flow after administration of estradiol 17beta (E2beta). Endometrial blood flow was repeatedly measured with the H2 gas clearance technique in ovariectomized rats. N(omega)-nitro-L-arginine methyl ester (L-NAME) dose dependently reduced basal endometrial blood flow and increased mean arterial blood pressure and endometrial vascular resistance. E2beta (1 microg/kg i.v.) increased endometrial blood flow and reduced endometrial vascular resistance, which peaked by 2 h after the injection. The vasoconstrictive activity of L-NAME (an inhibitor for NO synthesis) was compared with that of phenylephrine (PE, an alpha-receptor agonist acting through an NO independent mechanism). Doses of L-NAME (1 and 3 mg/kg i.v.) were matched with those of PE (3.2 and 6.4 mg x kg(-1) x h(-1) i.v.), as they induced an approximately equivalent percent increase in basal endometrial vascular resistance. The percent increases of endometrial vascular resistance in E2beta treated animals by the two agents in matched doses were also of a similar magnitude. When animals were first treated with L-NAME or PE, E2beta lost the ability to reduce endometrial vascular resistance. Enzyme activity and gene expression of NO synthase in the rat uterine tissue were also examined after E2beta treatment, and no significant changes were observed. These data raise doubts about the role of NO in the regulation of endometrial blood flow after acute administration of E2beta and suggest that other mechanisms may be involved. PMID- 9362274 TI - Echocardiographic changes after myocardial infarction in a model of left ventricular diastolic dysfunction. AB - To determine the early and late effects of myocardial infarction on left ventricular (LV) diastolic function in the rabbit postinfarction model, male New Zealand White rabbits were randomly assigned to ligation of the circumflex artery or sham operation. Serial echocardiographic and Doppler studies were performed on both groups of animals at baseline and 1 h and 3 wk after surgery (n = 10 for each group) after verification of the reproducibility and repeatability of the measurements. At 1 h postinfarction, decreases in early mitral inflow velocity (E wave) and mitral inflow velocity with atrial contraction (A wave) and increases in the mean pulmonary venous systolic-to-diastolic ratio and A wave reversal velocities were observed, without changes in LV geometry. By 3 wk postinfarction, increases in the mitral E-to-A ratio (1.1 +/- 0.3 vs. 2.9 +/- 0.9, P < 0.001) and left atrial area (131 +/- 23 vs. 510 +/- 72 mm2, P < 0.001) and decreases in the pulmonary venous systolic-to-diastolic ratio (0.56 +/- 0.20 vs. 0.79 +/- 0.14, P = 0.008) were consistent with severe diastolic abnormalities (restricted physiology). The findings of this study demonstrate that coronary artery ligation in the rabbit provides a reproducible echocardiographic and Doppler model of LV diastolic dysfunction that is consistent with abnormalities found in humans with previous myocardial infarction, symptoms of heart failure, and preserved LV systolic function. PMID- 9362275 TI - Vessel growth and collapsible pressure-area relationship. AB - The role that the pattern of vessel wall growth plays in determining pressure lumen area (P-A) and pressure-compliance curves was examined. A P-A vessel model was developed that encompasses the complete range of pressure, including negative values, and accounts for size given the fixed length, nonlinear elastic wall properties, constant wall area, and collapse. Data were obtained from excised canine carotid and femoral arteries, jugular veins, and elastic tubing. The mean error of estimate was 8 mmHg for all vessels studied and 2 mmHg for blood vessels. The P-A model was employed to examine two patterns of arterial wall thickening, outward growth and remodeling (constant wall area), under the assumption of constant wall properties. The model predicted that only outward wall growth resets compliance such that it increases at a given arterial pressure, explaining previously contradictory data. In addition, it was found that outward wall growth increases the lumen area between normal and high pressures. Remodeling resulted in lumen narrowing and a decrease in compliance for positive pressures. PMID- 9362276 TI - Left ventricular pressure response to small-amplitude, sinusoidal volume changes in isolated rabbit heart. AB - The objective was to determine the dynamics of contractile processes from pressure responses to small-amplitude, sinusoidal volume changes in the left ventricle of the beating heart. Hearts were isolated from 14 anesthetized rabbits and paced at 1 beats/s. Volume was perturbed sinusoidally at four frequencies (f) (25, 50, 76.9, and 100 Hz) and five amplitudes (0.50, 0.75, 1.00, 1.25, and 1.50% of baseline volume). A prominent component of the pressure response occurred at the f of perturbation [infrequency response, delta Pf(t)]. A model, based on cross-bridge mechanisms and containing both pre- and postpower stroke states, was constructed to interpret delta Pf(t). Model predictions were that delta Pf(t) consisted of two parts: a part with an amplitude rising and falling in proportion to the pressure around that which delta Pf(t) occurred [Pr(t)], and a part with an amplitude rising and falling in proportion to the derivative of Pr(t) with time. Statistical analysis revealed that both parts were significant. Additional model predictions concerning response amplitude and phase were also confirmed statistically. The model was further validated by fitting simultaneously to all delta Pf(t) over the full range of f and delta V in a given heart. Residual errors from fitting were small (R2 = 0.978) and were not systematically distributed. Elaborations of the model to include noncontractile series elastance and distortion-dependent cross-bridge detachment did not improve the ability to represent the data. We concluded that the model could be used to identify cross bridge rate constants in the whole heart from responses to 25- to 100-Hz sinusoidal volume perturbations. PMID- 9362277 TI - Modeling the myocardial dilution curve of a pure intravascular indicator. AB - The dispersion and dilution of contrast medium through the myocardial vasculature is examined first with a serial model comprised of arterial, capillary, and venous components in series to determine their time-concentration curves (TCC) and the myocardial dilution curve (MDC). Analysis of general characteristics shows that the first moment of the MDC, adjusted for that of the aortic TCC and mean transit time (MTT) from the aorta to the first intramyocardial artery, is one-half the MTT of the myocardial vasculature and that the ratio of the area of the MDC and aortic TCC is the fractional myocardial blood volume (MBV). The use of known coronary vascular morphometry and a set of transport functions indicates that the temporal change in MDC is primarily controlled by the MTT. An analysis of several models with heterogeneous flow distributions justifies the procedures to calculate MTT and MBV from the measured MDC. Compared with previously described models, the present model is more general and provides a physical basis for the effects of flow dispersion and heterogeneity on the characteristics of the MDC. PMID- 9362278 TI - Involvement of interleukin-1 receptor mechanisms in development of arterial hypotension in rat heatstroke. AB - Rats, under urethan anesthesia, were exposed to a high ambient temperature (42 degrees C) to induce heatstroke and to assess the hemodynamic changes associated with heatstroke. Compared with normothermic controls, rats with heatstroke showed higher values of colonic temperature, heart rate, and plasma levels of interleukin (IL)-1 but lower values of R wave amplitude, P-R and Q-T intervals, systolic wave amplitude, diastolic and dicrotic wave duration, mean arterial pressure, stroke volume, and cardiac output. Animals injected intravenously with an IL-1-receptor antagonist at the time of heatstroke induction were protected from some of the cardiovascular effects of heatstroke, such as depressed ventricular depolarization, decreased stroke volume, decreased cardiac output, and arterial hypotension. The hemodynamic changes associated with heatstroke could be mimicked by IL-1beta administration. Other cardiovascular parameters such as total peripheral vascular resistance were unaffected by heatstroke induction or IL-1beta treatment. The results indicate that a selective decline in stroke volume or ventricular depolarization resulting from increased plasma levels of IL-1 may be an important mechanism signaling arterial hypotension or circulatory failure in rat heatstroke. PMID- 9362279 TI - Transesophageal echocardiography in rats using an intravascular ultrasound catheter. AB - In vivo assessment of cardiac structure and function in small animals is an important experimental goal, but currently available techniques have significant limitations. A commercially available intravascular ultrasound (IVUS) system was adapted to perform transesophageal echocardiography (TEE) in rats. Twelve Sprague Dawley rats (270-370 g) were anesthetized with intraperitoneal pentobarbital sodium. A 4.3-Fr, 30-MHz or an 8-Fr, 20-MHz IVUS catheter was inserted into the esophagus to obtain long-axis views of the aortic arch, short-axis views of the ascending aorta, and long-axis views of the pulmonary artery. A preshaped, 8-Fr, 20-MHz catheter was used to obtain short-axis images of the left ventricle (LV) at the midpapillary muscle level, which were used to measure LV diastolic and systolic dimensions (diameters) and to calculate LV mass and fractional shortening. Measurements by TEE were compared with those obtained by transthoracic echocardiography in 6 of 12 rats. Postmortem, the LV was weighed to determine actual LV mass. The correlation coefficients between TEE- and transthoracic echocardiography-calculated LV mass and actual LV mass were 0.94 and 0.88, respectively, and had a good agreement with actual LV mass. Inter- and intraobserver variability of TEE measurements was <10%. IVUS instrumentation may offer an alternative technique for the accurate, serial assessment of LV dimensions, mass, and systolic function and a means of imaging the great vessels in small laboratory animals. PMID- 9362280 TI - Heterogeneity of L-type calcium current density in coronary smooth muscle. AB - Heterogeneity of vascular responses to physiological and pharmacological stimuli has been demonstrated throughout the coronary circulation. Typically, this heterogeneity is based on vessel size. Although the cellular mechanisms for this heterogeneity are unknown, one plausible factor may be heterogeneous distribution of ion channels important in regulation of vascular tone. Because of the importance of voltage-gated Ca2+ channels in regulation of vascular tone, we hypothesized that these channels would be unequally distributed throughout the coronary arterial bed. To test this hypothesis, voltage-gated Ca2+ current was measured in smooth muscle from conduit arteries (>1.0 mm), small arteries (200 250 microm), and large arterioles (75-125 microm) of miniature swine using whole cell voltage-clamp techniques. With 2 mM Ca2+ or 10 mM Ba2+ as charge carrier, voltage-gated Ca2+ current density was inversely related to arterial diameter, i.e., large arterioles > small arteries > conduit. Peak inward currents (10 mM Ba2+) were increased approximately 2.5- and approximately 1.5-fold in large arterioles and small arteries, respectively, compared with conduit arteries ( 5.58 +/- 0.53, -3.54 +/- 0.34, and -2.26 +/- 0.31 pA/pF, respectively). In physiological Ca2+ (2 mM), small arteries demonstrated increased inward current at membrane potentials within the physiological range for vascular smooth muscle (as negative as -40 mV) compared with conduit arteries. In addition, cells from large arterioles showed a negative shift in the membrane potential for half maximal activation compared with small and conduit arteries (-13.23 +/- 0.88, 6.22 +/- 1.35, and -8.62 +/- 0.81 mV, respectively; P < 0.05). Voltage characteristics and dihydropyridine sensitivity identified this Ca2+ current as predominantly L-type current in all arterial sizes. We conclude that L-type Ca2+ current density is inversely related to arterial diameter within the coronary arterial vasculature. This heterogeneity of Ca2+ current density may provide, in part, the basis for functional heterogeneity within the coronary circulation. PMID- 9362281 TI - Spectrum analysis of cardiovascular time series. AB - The demand for noninvasive assessment of cardiovascular control parameters has promoted the use of spectrum analysis. These techniques have been applied on a broad basis; however, because of the abstract mathematical approach, spectrum analysis in physiology is still not fully accepted by some circles in the scientific community. Thus it is the goal of the following review to focus on the rationale for applying spectrum analysis in different fields of circulation research, which range from determining arterial baroreceptor reflex sensitivity to the early detection of heart allograft rejection. Within this scope, major findings regarding the physiological and pathophysiological regulation of the cardiovascular system are discussed. In addition, inherent limitations of these methods are made clear. Toward the end of this survey, a perspective is provided for the general readership. PMID- 9362282 TI - Carbohydrate utilization in rat soleus muscle is influenced by carbonic anhydrase III activity. AB - Inhibition of carbonic anhydrase III (CA III; EC 4.2.1.1) activity in type I muscle can influence resistance to fatigue and glycogen utilization. Our aim was to determine if CA III inhibition could influence muscle pH and glycolytic rate. Muscle pH, hexosemonophosphates (HMP), glycolytic intermediates, ATP, and creatine phosphate (CP) were measured at rest and during a fatigue protocol in rat soleus muscles in vitro with or without CA inhibitors (CAI). In resting muscles, CAI resulted in a significant drop in pH (7.11 vs. 7.06, P < 0.05) and in a two- to threefold increase in HMP content compared with control muscles. Measurements of HMP and glycolytic intermediates during the fatigue protocol suggested, however, that the glycolytic flux was not influenced. Globally, muscles incubated with CAI showed larger perturbations of their CP and ATP content than control muscles. The accumulation of HMP induced by the CAI was found to be totally dependent on the combined presence of external glucose and contractile activity, suggesting that inhibiting CA III may augment the responsitivity of the contraction-induced glucose uptake process. PMID- 9362283 TI - Carotid baroreflex control of heart rate during acute exposure to simulated altitudes of 3,800 m and 4,300 m. AB - To examine the baroreflex response in humans during acute high-altitude exposure, the carotid baroreflex cardiac responsiveness was studied using a neck chamber in seven unacclimatized male subjects. Measurements were made in a high-altitude chamber on separate days at sea level and during 1-h exposure at two different altitudes of 3,800 m [partial pressure of oxygen in inspired air (PI(O2)) = 90 mmHg] and 4,300 m (PI(O2) = 82 mmHg). R-R intervals were plotted against neck chamber pressures, and the baroreceptor response was analyzed by applying a four parameter sigmoidal logistic function. The baroreceptor response curve shifted downward in either altitude, reflecting a tachycardic response at high altitude, and the magnitude of the shift was greater at 4,300 m than at 3,800 m. There was no change in the sigmoidal parameters at 3,800 m compared with sea level except for a reduction (P < 0.05) of the minimum R-R interval. At 4,300 m the maximal R R range, slope coefficient, minimum R-R interval, and maximal gain of the curve decreased significantly (P < 0.05) compared with sea level values, whereas the centering point of the curve remained unchanged. These results suggest that hypoxia (PI(O2) = 82 mmHg) reduces the sensitivity of carotid baroreflex cardiac response. PMID- 9362285 TI - Preference conditioning alters taste responses in the nucleus of the solitary tract of the rat. AB - Aversive conditioning has an impact on the neural signal for the gustatory conditioned stimulus (CS). Here, we determined whether the code is also affected by preference conditioning. We paired the taste of MgCl2 (CS+) with intragastric nutrients in some rats (MG), and citric acid (CS+) with nutrients in others (CI). A control group (Control) experienced both tastants without nutrients. Preferences (>90%) developed for each CS+. We recorded responses to 16 taste stimuli in the nucleus of the solitary tract. Responsiveness of acid-oriented neurons to MgCl2 in MG rats was lower than in Controls, and its profile was more distinct from those of acidic and bitter stimuli. Total activity to citric acid was unchanged in CI rats. However, its temporal profile showed a decreased phasic component, making citric acid temporally distinct from nonsugars. Therefore, the responses to both CS+ were modified, each in its own manner, to be more distinct from those of aversive stimuli. The effects of preference conditioning, however, were weaker than those of aversive conditioning. PMID- 9362284 TI - Regulation of type 1 ANG II receptor in vascular tissue: role of alpha1 adrenoreceptor. AB - Angiotensin II (ANG II) and norepinephrine (NE) are important regulators of vascular function and structure. Recent studies showed that there are multiple interactions between these two potent vasoconstrictor agents. The present experiment was designed to investigate the effect of NE on the expression of the type 1 ANG II receptor (AT1) in the aorta and cultured vascular smooth muscle cells (VSMC) of rats. Rats were subcutaneously infused with either NE (0.5 microg x kg(-1) x min(-1), n = 6) or the alpha1-adrenoreceptor antagonist prazosin (3.5 microg x kg(-1) x min(-1), n = 6) for 2 wk. Body weight and tail cuff systolic blood pressure were not modified compared with the vehicle control (P > 0.05). Northern blot analysis showed that AT1 mRNA levels in aorta were decreased by 38% in NE-treated rats and increased 117% in prazosin-treated rats (P < 0.05) compared with control. To determine whether NE directly regulates expression of vascular AT1 mRNA and AT1 receptor density, Northern blot analysis and radioligand binding experiments were performed in cultured VSMC. Incubation of VSMC with NE (10(-7) M) led to 44% decrease in AT1 mRNA levels (P < 0.05) and 39% decrease in AT1 receptor density (P < 0.05). Prazosin, but not the alpha2 adrenoreceptor antagonist yohimbine, prevented NE-induced decrease in AT1 mRNA and AT1 receptor density in these cells. Taken together, our results indicate that vascular AT1 gene expression and receptor protein are regulated by ambient NE levels, and NE-induced downregulation of AT1 mRNA and receptor protein is mediated, at least in part, by activating alpha1-adrenoreceptors. PMID- 9362286 TI - Dietary NaCl and KCl do not regulate renal density of the thiazide diuretic receptor. AB - We tested the postulate that the renal density of the thiazide-inhibitable Na-Cl cotransporter or thiazide receptor (TZR) is modulated as part of the renal homeostatic response to changes in dietary intake of NaCl or KCl. Renal excretion of NaCl or KCl varied > 10-fold in response to alterations in oral intake. Renal TZR density was quantitated by binding of [3H]metolazone to renal membranes. Renal TZR density was not altered by sodium deficit (with increased plasma aldosterone concentration), by sodium surfeit (8% NaCl content of diet), by potassium deficit (with hypokalemia), or by potassium surfeit (drinking 1% KCl solution). Unexpectedly, we conclude that regulation of the renal density of TZR is not part of the renal homeostatic responses that adjust excretion of NaCl and KCl to changes in dietary intake of NaCl or KCl. PMID- 9362287 TI - Subdiaphragmatic vagotomy blocks the sleep- and fever-promoting effects of interleukin-1beta. AB - The mechanism by which peripheral cytokines signal the central nervous system to elicit central manifestations of the acute phase response remains unknown. Recent evidence suggests that cytokines may signal the brain via the vagus nerve. To test this possibility, we examined sleep-wake activity and brain temperature (Tbr) after the intraperitoneal administration of saline or three doses (0.1, 0.5, and 2.5 microg/kg) of interleukin-1beta (IL-1beta) in subdiaphragmatically vagotomized (Vx) and sham-operated (Sham) rats. The lowest dose of IL-1beta (0.1 microg/kg) increased non-rapid eye movement sleep (NREMS) and slightly elevated Tbr in Sham rats; both responses were blocked in Vx animals. The middle dose tested (0.5 microg/kg) increased NREMS and Tbr in Sham animals; however, in Vx rats, the increase in NREMS was attenuated and the increase in Tbr was blocked. The highest dose of IL-1beta used (2.5 microg/kg) induced increases in NREMS, decreases in rapid eye movement sleep, and a hypothermic response followed by a biphasic fever; these responses were similar in both Sham and Vx rats. These data provide strong evidence that the subdiaphragmatic vagus plays an important role in communicating both sleep and fever signals to the brain. However, there is clearly an alternative pathway by which IL-1 can signal the brain; whether it occurs through activation of other vagal afferents or through direct or indirect actions on the brain remains unknown. PMID- 9362288 TI - Methotrexate potentiates bradykinin-induced increase in macromolecular efflux from the hamster oral mucosa. AB - The purpose of this study was to determine whether methotrexate modulates bradykinin-induced increase in macromolecular efflux from the in situ oral mucosa and whether this response is mediated by the L-arginine/nitric oxide biosynthetic pathway. Using intravital microscopy, we found that suffusion of methotrexate alone onto the hamster cheek pouch had no significant effects on leaky site formation and increase in clearance of fluorescein isothiocyanate-labeled dextran (molecular mass, 70 kDa). However, methotrexate significantly potentiated bradykinin-induced responses (P < 0.05). These effects were associated with significant increases in nitrites concentration and guanosine 3',5'-cyclic monophosphate-like immunoreactivity in the suffusate and were abrogated by N(G) nitro-L-arginine methyl ester (L-NAME) but not N(G)-nitro-D-arginine methyl ester (D-NAME). L-Arginine, but not D-arginine, abolished L-NAME-induced responses. ZnCI2 and indomethacin had no significant effects on methotrexate-induced responses. Methotrexate had no significant effects on adenosine- and ionomycin induced increases in macromolecular efflux. Collectively, these data indicate that methotrexate amplifies bradykinin-induced increase in macromolecular efflux from the in situ oral mucosa in a specific, receptor- and L-arginine/nitric oxide biosynthetic pathway-dependent fashion. PMID- 9362289 TI - Effect of oral versus gastric delivery on gastric emptying of corn oil emulsions. AB - Several studies have shown that fluids delivered to the stomach tend to empty more rapidly than when ingested by mouth. To better characterize the "delivery route effect" for corn oil, rats received intragastric or intraoral infusions matched for concentration and for the rate and duration of stimulus delivery. We showed, first, that more than twice as much oil emptied by the end of 12-min intragastric versus intraoral infusions but that the emptying curves remained roughly parallel for 1 h after infusion offset. Remaining experiments therefore focused on stimulus parameters of relevance to emptying control during stomach fill. Emptying during intragastric infusions approximately doubled with doublings of oil concentration (25-50%), infusion duration (6-12 and 12-24 min), and infusion rate (0.5-1.0 ml/min). Emptying during intraoral infusions, by contrast, was entirely unaffected by these manipulations. Unlike oil emptying, glucose emptying did not vary as a function of delivery route. The nutrient specificity of the delivery route effect cannot be explained in terms of energy density, as the effect was obtained for oil but not for glucose when their energy densities were equated (50% glucose, 25% corn oil). In discussion, we suggest that the oral influence on corn oil emptying during stomach fill is a gating factor that enables the expression of inhibition derived from postgastric nutrient stimulation. PMID- 9362290 TI - Modulation of exercise tachycardia by vasopressin in the nucleus tractus solitarii. AB - Our objective was to study the role of vasopressinergic synapses at the nucleus tractus solitarii (NTS) in the modulation of exercise-induced tachycardia. We evaluated the effect of NTS administration of vasopressin (AVP) or vasopressin antagonist (AVP(ant)) on heart rate (HR) and mean arterial pressure (MAP) responses during dynamic exercise in male rats with chronic arterial and NTS cannulas. Sedentary (S) and trained (T) animals were tested at three or four exercise levels (from 0.4 up to 1.4 km/h) after NTS injection of AVP or AVP(ant) 20-30 min before treadmill exercise. Plasma and regional brain levels of AVP were measured in separate groups of S and T rats at rest and immediately after acute exercise. When administered into the NTS, exogenous AVP (20 pmol) caused a small but significant decrease in baseline HR and potentiated the tachycardiac response to mild to moderate exercise intensities (on average, increases of 35-46 beats/min over control tachycardic response). The potentiation of exercise tachycardia by AVP was long lasting and more pronounced in T than in S rats. Even 2 days after NTS AVP injection, there was evidence for an alteration in the HR response to exercise. Mediation by V1 receptors was supported by the blunted tachycardiac response to exercise after administration of a V1 antagonist d(CH2)5Tyr MeAVP into the NTS in both T and S rats (average reductions of 23-34 and 13-19 beats/min below control tachycardia, respectively). No changes were observed in baseline MAP or the exercise-induced pressor responses. There were specific changes in brain stem AVP levels that were related to the exercise treatment. T rats showed a marked increase in dorsal and ventral brain stem AVP content after acute exercise. There were no changes in hypothalamus, median eminence, posterior pituitary, or plasma AVP. These data indicate that vasopressinergic synapses and V1 receptors in the NTS are involved in the potentiation of tachycardic response to exercise. The vasopressinergic mechanism operates in both S and T rats, but training alters the sensitization of V1 receptors by AVP. PMID- 9362291 TI - Key role for cyclooxygenase-2 in PGE2 and PGF2alpha receptor regulation and cerebral blood flow of the newborn. AB - Ibuprofen, a cyclooxygenase (COX) inhibitor nonselective for either COX-1 or COX 2 isoform, upregulates cerebrovascular prostaglandin E2 (PGE2) and PGF2alpha receptors in newborn pigs. COX-2 was shown to be the predominant form of COX and the main catalyst of prostaglandin synthesis in the newborn brain. We proceeded to establish direct evidence that COX-2-generated prostaglandins govern PGE2 and PGF2alpha receptor density and function in the cerebral vasculature of the newborn. Hence, we determined PGE2 and PGF2alpha receptor density and functions in brain vasculature by using newborn pigs treated with saline, ibuprofen, COX-1 inhibitor (valerylsalicylate), or COX-2 inhibitors (DUP-697 and NS-398). Newborn brain PGE2 and PGF2alpha concentrations were significantly reduced by ibuprofen, DUP-697, and NS-398 but not by valerylsalicylate. In newborn pigs treated with DUP-697, NS-398, and ibuprofen, PGE2 and PGF2alpha receptor densities in brain microvessels were increased to adult levels; there was also a significant increase in inositol 1,4,5-trisphosphate (IP3) production and cerebral vasoconstrictor effects of 17-phenyl trinor PGE2 (EP1 receptor agonist), M&B 28767 (EP3 receptor agonist), PGF2alpha, and fenprostalene (PGF2alpha analog). Treatment with ibuprofen or DUP-697 also increased the upper blood pressure limit of cerebral cortex and periventricular blood flow autoregulation from 85 to > or = 125 mmHg (uppermost blood pressure studied). However, valerylsalicylate treatment did not affect cerebrovascular PGE2 and PGF2alpha receptors, IP3 production, or vasoconstrictor effects in newborn animals. These in vivo and in vitro observations indicate that COX-2 is mainly responsible for the regulation of PGE2 and PGF2alpha receptors and their functions in the newborn cerebral vasculature. PMID- 9362292 TI - Serotonergic modulation of hippocampal pyramidal cells in euthermic, cold acclimated, and hibernating hamsters. AB - Serotonergic fibers project to the hippocampus, a brain area previously shown to have distinctive changes in electroencephalograph (EEG) activity during entrance into and arousal from hibernation. The EEG activity is generated by pyramidal cells in both hibernating and nonhibernating species. Using the brain slice preparation, we characterized serotonergic responses of these CA1 pyramidal cells in euthermic, cold-acclimated, and hibernating Syrian hamsters. Stimulation of Shaffer-collateral/commissural fibers evoked fast synaptic excitation of CA1 pyramidal cells, a response monitored by recording population spikes (the synchronous generation of action potentials). Neuromodulation by serotonin (5-HT) decreased population spike amplitude by 54% in cold-acclimated animals, 80% in hibernating hamsters, and 63% in euthermic animals. The depression was significantly greater in slices from hibernators than from cold-acclimated animals. In slices from euthermic animals, changes in extracellular K+ concentration between 2.5 and 5.0 mM did not significantly alter serotonergic responses. The 5-HT1A agonist 8-hydroxy-2(di-n-propylamino)tetralin mimicked serotonergic inhibition in euthermic hamsters. Results show that 5-HT is a robust neuromodulator not only in euthermic animals but also in cold-acclimated and hibernating hamsters. PMID- 9362293 TI - Differential effects of dorsomedial medulla lesion size on ingestive behavior in rats. AB - Previous studies indicate that rats with lesions centered on the area postrema (AP) drink more saline and consume abnormally large amounts of water after treatment with subcutaneous isoproterenol (Iso) angiotensin II. In addition, lesioned rats lose a significant amount of body weight immediately after surgery. Nonetheless, there are disparate reports on the effects of lesions of the AP on fluid intake and body weight. These reports suggest that the adjacent nucleus of the solitary tract (NTS) may play a role in the effects observed subsequent to the lesion. In this study we evaluated the effects of varying lesion size on body weight, fluid intake, and the baroreflex. As the lesion included more of the NTS, the effect on body weight was reduced. Moreover, water intake induced by Iso increased as more NTS was involved in the lesion. Conversely, 3-h ad libitum saline intake and saline intake after sodium depletion decreased with more involvement of the NTS in the lesion. These data suggest that the neural population in the NTS bordering the AP may play a critical role in the control of water and saline intake as well as the regulation of body weight. PMID- 9362294 TI - Targets for SMR1-pentapeptide suggest a link between the circulating peptide and mineral transport. AB - The submandibular rat 1 protein (SMR1) is selectively processed at pairs of basic amino acid residues in a tissue- and sex-specific manner. We have mapped peripheral targets for the final secretory maturation product of SMR1, the pentapeptide QHNPR, by examining in vivo the tissue distribution of the radiolabeled peptide using beta-radio imager whole body autoradiography. The characteristics of tissue uptake allowed specific binding sites at physiological peptide concentrations to be identified within the renal outer medulla, bone and dental tissue, glandular gastric mucosa, and pancreatic lobules. Direct evidence that pentapeptide binding sites are localized in selective portions of the male rat nephron, within the S3, S2, and S1 segments of the proximal tubules, was obtained. In bone tissue the pentapeptide exclusively accumulates within the trabecular bone remodeling unit, and in dental tissue it concentrates within the tubules of the dentinal rat incisor. In relation to male rat-specific behavioral characteristics, our data suggest that the circulating androgen-regulated SMR1 derived pentapeptide is primarily involved in the modulation of mineral balance between at least four systems: kidney, bone, tooth, and circulation. PMID- 9362295 TI - Organization of circadian rhythmicity and suprachiasmatic nuclei in malnourished rats. AB - The present study was aimed at characterizing the effects of low-protein malnutrition (6% casein) on the circadian rhythm of drinking behavior and on suprachiasmatic nuclei immunohistochemistry in Sprague-Dawley rats. Recordings were started at 30 days of age under a 12:12-h light-dark (LD) cycle. At age 150 days, recordings were continued under constant dim red light, and finally the latency to entrain to complete and skeleton photoperiods was established. At the end of the recordings rats were processed for histological analysis. Compared with their controls, malnournished rats exhibited 1) splitting of rhythmicity under LD that 2) condensed to one component in constant dim red light, 3) delayed entrainment to skeleton photoperiod, and 4) precocious entrainment under complete photoperiod. Immunohistochemical analysis showed mainly a decrease in the immunohistochemical detection of vasoactive intestinal polypeptide and glial fibrillar acid protein cells in malnourished animals. These results indicate that in malnourished rats there is a decrease 1) in the coupling force among the oscillators and 2) in the strength of the phase lock between the oscillators and the light-dark cycle. PMID- 9362296 TI - Long-term effects of maternal deprivation on the corticosterone response to stress in rats. AB - Twenty-four hours of maternal deprivation result in activation of the infant rat's adrenocortical axis. In the present study we examined the long-term effects of maternal deprivation on the corticosterone (Cort) response to stress. Pups were maternally deprived (Dep) on postnatal day (PND) 11 and tested immediately (PND 12) or returned to their mothers and tested at later ages. Testing consisted of a time course of the Cort response to a saline injection (5, 15, 30, and 60 min). At PND 12, the response of Dep pups was higher than that of nondeprived (non-Dep) pups. No group differences were observed at PND 16 and 22. On PND 30, Dep rats showed lower Cort levels than non-Dep pups at 0, 5, and 30 min after saline. At PND 60, non-Dep females showed higher Cort levels than males at 5, 15, and 30 min. This gender difference for Dep pups was observed only at 5 min. Male and female Dep animals presented lower Cort levels than non-Dep counterparts at 60 and 30 min after saline, respectively. These findings indicate that maternal deprivation effects on Cort secretion are long lasting. Dep rats showed a smaller adrenal response to stress at PND 30, whereas as adults the stress response was similar but the turnoff was different. PMID- 9362297 TI - Role of L-type Ca2+ channel in PACAP-induced adrenal catecholamine release in vivo. AB - The aim of the present study was to investigate whether the dihydropyridine sensitive L-type Ca2+ channel is operative in adrenal catecholamine (CA) secretion induced by a novel neuropeptide, pituitary adenylate cyclase-activating polypeptide (PACAP), in anesthetized dogs. Plasma CA concentrations in adrenal venous and aortic blood were determined by a high-performance liquid chromatography method. All drugs tested were locally infused into the left adrenal gland via the left adrenolumbar artery. PACAP, with the isoform consisting of 27 (PACAP-27) and 38 (PACAP-38) amino acid residues, significantly increased CA output in a dose-dependent manner, with doses ranging from 5 to 500 ng and 7 to 700 ng, respectively. However, the amplitude of epinephrine response to PACAP-27 was three times greater than that obtained with PACAP-38 at the highest dose tested. In a separate group, a single dose of PACAP-27 (50 ng) induced highly reproducible CA responses when the same dose was repeated with an interval of 35 min. In dogs treated with nifedipine (50 microg), 5 min before the second administration of PACAP-27, the net CA response was significantly inhibited by approximately 50% compared with that obtained in the presence of vehicle. A similar CA response to BAY K 8644 (5 microg) was completely abolished by the same dose of nifedipine. The present results indicate that both PACAP-27 and PACAP-38 have the direct local secretagogue effect on the adrenal medulla in vivo and that CA responses to PACAP-27 were greater than those observed with PACAP-38 at equivalent mole doses. The study suggests that the dihydropyridine sensitive L-type Ca2+ channel is functionally involved in PACAP-induced adrenal CA secretion in the canine adrenal medulla in vivo. PMID- 9362298 TI - Insulin-like growth factor I is suppressed in socially subordinate male baboons. AB - Insulin-like growth factor (IGF) I is a potent growth-promoting and anabolic hormone with major roles in cellular growth and differentiation, protein metabolism and muscle physiology, wound healing, erythropoiesis, and immune stimulation. Few, if any, studies have examined social or psychological factors that could give rise to individual differences in IGF-I levels. As part of a long term psychoendocrine study of a population of male baboons living freely in a national reserve in East Africa, we examined the relationship between social rank and IGF-I concentrations. We observed that social subordinance was associated with a relative suppression of IGF-I concentrations; no rank-related differences in concentrations of IGF-II or IGF-binding protein were observed. Extensive psychoendocrine literature suggests that the individual differences in IGF-I profiles were a consequence, rather than a cause, of the rank difference. We were able to rule out a number of possible proximal explanations for the rank-IGF-I correlation: 1) the correlation was not a function of age (which involves both an adolescent spurt in IGF-I concentrations as well as a decline in concentrations in aged individuals); 2) the IGF-I suppression in subordinate individuals could not be explained by the basal hypercortisolism typical of such subordinate animals; and 3) neither differences in the quality or quantity of food consumed, in basal testosterone concentrations, nor in genetics could explain the rank difference. Although the mediating mechanisms responsible for this rank difference were not discernible in this study, the magnitude of difference in IGF I levels among baboons of differing ranks might be of physiological significance. PMID- 9362299 TI - Lack of locomotor-cardiac coupling in trotting dogs. AB - Coupling of locomotor and cardiac cycles has been suggested to facilitate effective arterial delivery and venous return during vigorous exercise. In an attempt to document locomotor-cardiac coupling, we ran five dogs on a motorized treadmill while monitoring heart activity with surface electrocardiogram electrodes and locomotor events with high-speed video and an accelerometer mounted on the dog's back. Analysis of the cardiac and locomotor frequencies revealed that heart rate was usually slightly greater than stride frequency. Hence the timing of the cardiac cycles varied with respect to the phase of the locomotor cycles, and therefore consistent coupling of the locomotor and cardiac cycles was not observed in any of the dogs. However, the period of the cardiac cycle sometimes varied in a rhythmic way that caused brief periods of transient coupling of the locomotor and cardiac cycles in three of the five dogs. These brief periods of coupling (5-20 heartbeats) occurred at approximately the same phase relationship in each of the three dogs. We hypothesize that the variation in cardiac period and the resulting transient coupling are a function of locomotor and ventilatory influences on venous return and/or ventricular ejection. Because venous return and ejection fraction are likely to vary in an unpredictable manner when animals run in a complex environment, we suggest that reflex control of heart rate will be important during locomotion and strict integer coupling of the locomotor and cardiac cycles is unlikely to evolve. PMID- 9362300 TI - Cardiovascular responses to vaginocervical stimulation in the spinal cord transected rat. AB - The present study ascertained whether increases in heart rate (HR) and systolic blood pressure (SBP) produced by vaginocervical stimulation (VS; 500 g force) persist in the unanesthetized rat after chronic spinal cord transection at selected levels. Three groups were used: spinal cord transection at T7 (n = 10) or L5 (n = 10) or a sham-operated control group (Sh, n = 10). In the Sh group, VS increased significantly both HR, by 95 +/- 14.3 beats/min (bpm) (22 +/- 3.7% above baseline), and BP, by 37 +/- 5.7 mmHg (37 +/- 7.7% above baseline), confirming earlier findings. In the T7 group, VS significantly decreased HR by 107 +/- 21.4 bpm (27 +/- 4.1% below baseline) and increased BP by 41.3 +/- 12.9 mmHg (32 +/- 8.3% above baseline). In response to VS, HR increased in every rat in the Sh group and decreased in every rat in the T7 group. In the L5 group, VS failed to significantly affect HR or BP. In the present study, specific levels of spinal cord transection produced differential HR and BP responses to VS in the rat. A model is presented addressing the component responses of autonomic dysreflexia that can occur, contingent on the level of spinal cord injury, in women during parturition or sexual intercourse. PMID- 9362301 TI - Maturation alters cerebral NOS kinetics in the spontaneously hypertensive rat. AB - Using 14C-labeled arginine to 14C-labeled citrulline conversion assays in brain homogenates from 14- to 18-day-old and adult spontaneously hypertensive rats, we tested the hypotheses that maturation increases neuronal nitric oxide synthase (nNOS) activity and that this increase involves changes in cofactor availability and/or nNOS kinetics. nNOS activity (in pmol x mg(-1) x min(-1)) was 46% higher in adults (19 +/- 2) than in pups (13 +/- 1). The addition of 264 microM calmodulin (CaM), 3 microM FAD, 3 microM flavin adenine mononucleotide (FMN), and 10 microM tetrahydrobiopterin (BH4) increased NOS activity by 3, 46, 45, and 88% in pups and by 19, 40, 36, and 102% in adults, respectively. All cofactor effects were significant except for CaM in the pup homogenates. Cofactor effects were not significantly different between pup and adult homogenates, except for BH4, which increased absolute NOS activity more in adults than in pups. Values of maximal enzyme velocity (Vmax) for nNOS in the absence of added cofactors were greater in adults than in pups (104 +/- 5 vs. 53 +/- 3, P < 0.05). Addition of 3 microM FAD or 3 microM FMN increased pup Vmax values to 68 +/- 2 and 99 +/- 5, respectively, but had no effect in adults. BH4 did not affect Vmax in either group. Control values of the Michaelis-Menten constant (Km) for L-arginine were greater (P < 0.05) in pups (5.7 +/- 0.4 microM) than in adults (4.3 +/- 0.2 microM) and were significantly reduced by 10 microM BH4 to 3.8 +/- 0.2 and 2.9 +/- 0.1 microM, respectively. Neither FAD nor FMN affected Km values in either group. The results indicate that endogenous nNOS cofactor levels are not saturating in either pups or adults, changes in cofactor levels differentially affect NOS kinetics in pups and adults, and age-related differences in NOS activity result from fundamental differences in NOS kinetics. These findings support the general hypothesis that the increased vulnerability to ischemic stroke associated with maturation is due in part to corresponding increases in the capacity for nitric oxide synthesis. PMID- 9362302 TI - A1 adenosine receptors potently regulate heart rate in mammalian embryos. AB - A1 adenosine receptors (A1ARs) have been recently shown to be expressed in rodent embryonic hearts at very early stages of development. To determine the functional significance of fetal cardiac A1AR expression during embryogenesis, murine fetal heart preparations were studied between postconceptual days 9 and 12. Dose response curves generated using a variety of adenosine agonists revealed that A1AR activation potently regulated fetal heart rates. The A1AR agonist, N6 cyclopentyladenosine, inhibited heart rates in a dose-dependent manner (half maximal effective concentration = 3.6 x 10(-8) M) and stopped fetal cardiac contractions in 63% of preparations. In contrast, A2a and A2b receptor activation did not alter heart rates, and activation of A3 receptors produced modest declines in heart rates. Endogenous adenosine also acted tonically to suppress fetal heart rates, as demonstrated by the A1AR antagonist 1,3-dipropyl-8 cyclopentylxanthine, increasing heart rates, whereas the adenosine reuptake blocker dipyridamole lowered fetal heart rates. Pertussis toxin treatment blocked A1AR action, showing that A1AR action was G protein mediated. Using drugs that alter cAMP levels and ion channel action, we were able to show that A1AR action involves events mediated by cAMP, ATP-dependent K, L-type calcium, sodium, and chloride channels, and the pacemaker current. These data show that adenosine and A1ARs potently regulate mammalian heart rates via multiple effector systems at very early stages of prenatal development. PMID- 9362303 TI - Repeated sodium depletion affects gustatory neural responses in the nucleus of the solitary tract of rats. AB - Furosemide sodium depletions were induced repeatedly to determine the effects on gustatory neural responses in the nucleus of the solitary tract (NST) of chronically prepared, but lightly anesthetized, rats. Sodium-replete and sodium deplete conditions were alternated four times in each rat. When rats were under depleted conditions, the responses to NaCl were significantly greater than in sodium-replete conditions. This effect was attributable primarily to an increase in the magnitude of response of those neurons that responded better to NaCl than to the other standard stimuli (sucrose, citric acid, and quinine hydrochloride). In addition, the largest change in responsiveness of the NaCl-best neurons occurred during the third and fourth sodium depletions. These results are essentially opposite to those reported for NST neurons when sodium appetite is induced by dietary sodium restriction. This suggests that the coding of intensity in the gustatory system is dependent not only on the animal's deprivation condition, but also the method through which the deprivation is produced. PMID- 9362304 TI - Adrenomedullin in experimental congestive heart failure: cardiorenal activation. AB - Adrenomedullin (ADM) is a new member of a family of vasodilating and natriuretic peptides that plays an important role in cardiorenal regulation. This study was designed to establish the plasma, urinary, cardiac, and renal tissue concentrations and immunohistochemical localizations of ADM in normal dogs and dogs with experimental congestive heart failure (CHF) produced by rapid ventricular pacing. Plasma ADM concentration was 5.6 +/- 0.4 pg/ml in normal dogs and significantly increased to 14.5 +/- 2.5 pg/ml in CHF dogs (P < 0.05). Ventricular and renal tissue ADM were significantly increased in CHF dogs compared with normals. Immunohistochemical examination revealed positive ADM immunostaining within the myocytes, and ventricular ADM immunoreactivity was significantly more intense in CHF dogs than in normals. ADM immunoreactivity was also observed in the glomerulus, distal tubules, and medullary collecting duct cells in the kidney, and the intensities of ADM immunoreactivity in these sites were increased in CHF dogs compared with normals. In addition, ventricular ADM was a powerful marker for left ventricular mass, and circulating ADM correlated positively with left ventricular end-diastolic pressure and inversely with cardiac output and ejection fraction. Despite an increase in renal tissue ADM, urinary ADM did not increase in CHF dogs. The current study demonstrates that plasma concentration of ADM is increased in experimental CHF and that ventricular and renal ADM is activated in the progression of CHF. Tissue and circulating ADM also are markers for the alterations in myocardial structure and function. This study supports a potential role for ADM in the neurohumoral activation in experimental CHF. PMID- 9362305 TI - Role of guanylyl cyclase receptors for CNP in salt secretion by shark rectal gland. AB - The role of C-type natriuretic peptide (CNP) and its guanylyl cyclase-linked receptors in mediating salt secretion by the rectal gland of the spiny dogfish shark (Squalus acanthias) was investigated using HS-142-1, a competitive inhibitor of the binding of natriuretic peptides to their guanylyl cyclase receptors. CNP binds to receptors and activates guanylyl cyclase in rectal gland membranes in a way that is inhibited by HS-142-1. Guanylyl cyclase activation in rectal gland membranes is far more sensitive to CNP than to atrial natriuretic peptide, whereas the reverse is true for membranes derived from mammalian (rabbit) renal collecting duct cells. HS-142-1 inhibited the stimulatory effect of CNP on ouabain-inhibitable oxygen consumption by rectal gland tubules. In explanted rectal glands continuously perfused with blood from intact donor sharks, HS-142-1 inhibited the increase in salt secretion normally provoked by infusing isotonic saline solutions into the donor animal. These results strongly support the view that CNP released into the systemic circulation in response to volume expansion mediates the secretion of chloride by the rectal gland via receptors linked to guanylyl cyclase. PMID- 9362306 TI - Aging alters feed-forward and feedback linkages between LH and testosterone in healthy men. AB - To discern the effect of aging on coordinate luteinizing hormone (LH) and testosterone secretion, we sampled healthy older men (age 62-74 yr, n = 11) and young controls (age 21-34 yr, n = 13) every 2.5 min overnight. Deconvolution analysis and cross-correlation were used to relate serum LH concentrations to calculated testosterone secretion rates (feed-forward stimulation), as well as serum testosterone concentrations to computed LH secretion rates (feedback inhibition). Despite statistically similar mean serum LH and testosterone concentrations in the young and older men, older individuals had diminished feed forward stimulation of LH concentrations on calculated testosterone secretion rates, as well as delayed feedback inhibition of testosterone concentrations on computed LH secretion rates. PMID- 9362307 TI - Reduced proximal reabsorption resets tubuloglomerular feedback in euvolemic rats. AB - Inhibition of renal carbonic anhydrase reduces proximal reabsorption and activates tubuloglomerular feedback (TGF). The TGF response is saturable, with highest gain focused near the natural flow rate. Therefore, any large change imposed on ambient tubular flow should reduce the TGF response to subequent flow perturbations. However, TGF tends to align with ambient flow regardless of the rate of ambient flow, suggesting that TGF resets to accommodate changes in flow while maintaining feedback efficiency. We used micropuncture and videometric flow velocitometry to test for TGF resetting in free-flowing nephrons during systemic infusion of the carbonic anhydrase inhibitor benzolamide (BNZ, 5 mg x kg(-1) x h( 1)) in euvolemic rats. Late proximal flow (V(LP)) and the fractional compensation (C) of TGF for perturbations in V(LP) were assessed repeatedly before and during BNZ. Early on, BNZ reduced C, consistent with TGF saturation. Over the next 45-60 min, V(LP) increased gradually by approximately 5 nl/min as C recovered to pre BNZ levels. BNZ also increased V(LP) by approximately 5 nl/min when TGF was rendered inoperative by intratubular wax block, but this increase occurred rapidly. These data demonstrate rightward resetting of TGF during reduced proximal reabsorption. PMID- 9362308 TI - Renal adaptation to dietary sodium restriction and loading in rats treated neonatally with enalapril. AB - Neonatal treatment of rats with angiotensin-converting enzyme inhibitors or the angiotensin II type 1 receptor antagonist losartan induces irreversible renal histological abnormalities, mainly papillary atrophy, in association with an impairment in urinary concentrating ability. In the present study, sodium and potassium balance were assessed during high and low sodium intake and dietary potassium restriction in adult Wistar rats treated neonatally with enalapril (10 mg x kg(-1) x day(-1)) from 3 to 24 days of age. During balance studies, neonatally enalapril-treated rats showed 1) normal adaptation to dietary sodium restriction, 2) sodium retention during dietary sodium loading, and 3) a transient, modest, renal potassium wastage during dietary potassium restriction. Renal clearance determinations under pentobarbital anesthesia showed elevated fractional excretions of sodium and potassium and osmolar clearance without changes in glomerular filtration rate or effective renal plasma flow in enalapril treated compared with vehicle-treated rats. Thus, in addition to the impaired urinary concentrating ability, adult rats treated neonatally with enalapril demonstrated alterations in renal sodium and potassium handling, which may be related to the prevailing papillary atrophy. PMID- 9362309 TI - cAMP and protein kinase A modulate cholinergic rapid eye movement sleep generation. AB - Cholinergic neurotransmission in the medial pontine reticular formation (mPRF) modulates rapid eye movement (REM) sleep generation. Microinjection of cholinergic agonists and acetylcholinesterase inhibitors into the mPRF induces a REM sleep-like state, and microdialysis data reveal increased mPRF levels of acetylcholine during REM sleep. Muscarinic cholinergic receptors (mAChRs) participate in REM sleep generation, and data suggest that mAChRs of a non-M1 subtype modulate REM sleep generation. The signal transduction pathway activated by m2 and m4 mAChRs involves a pertussis toxin-sensitive G protein, adenylate cyclase (AC), adenosine 3',5'-cyclic monophosphate (cAMP), and protein kinase A (PKA). Therefore, the present study tested the hypothesis that cAMP and PKA within the mPRF modulate the carbachol-induced REM sleep-like state. To test this hypothesis, the mPRF was microinjected with compounds known to facilitate the effects of cAMP (dibutyryl cAMP and 8-bromo-cAMP), stimulate PKA (Sp-cAMP[S]), and inhibit PKA (Rp-cAMP[S]). The results showed that compounds that fostered the intracellular effects of cAMP significantly decreased cholinergic REM sleep, while having no effect on spontaneously occurring REM sleep. These data are consistent with the recent finding that within the mPRF, AC and a pertussis toxin sensitive G protein modulate cholinergic REM sleep generation. These new data suggest a modulatory role for pontine cAMP and PKA in cholinergic REM sleep regulation. PMID- 9362310 TI - Aging and fluid homeostasis in rats. AB - The capacity of aging rats to defend body fluid homeostasis in response to a variety of dipsogenic and natriorexigenic stimuli was assessed. Male and female rats of both the Fischer 344 (FR) and Sprague-Dawley (SD) strains were used and tested at target ages of approximately 5, 10, 15, and 20 mo in both longitudinal and cross-sectional studies. There were no consistent age-related declines in water intake in response to water deprivation or acute administration of hypertonic NaCl; angiotensin (ANG) I, II, III; or isoproterenol. Likewise, there were no major impairments in either urinary excretion of the hypertonic NaCl load or excretion of water or hypotonic NaCl loads, although the latter were excreted more slowly in the older cohorts. The preference/aversion functions for NaCl solutions differed between SD and FR rats, but did not change with age except in male FR rats that lost their aversion to dilute NaCl at 20 mo of age. Intake of hypotonic NaCl solution after acute sodium depletion (furosemide treatment) showed a partial decline with age, and the older rats sustained larger estimated sodium deficits after a 6-h repletion period. A more complete age-related decline was observed in the intake of hypertonic NaCl stimulated by chronic dietary administration of a kininase II inhibitor (ramipril). Male rats of 15-20 mo of age showed no ramipril-induced sodium appetite. Brain ANG II receptor density, determined by autoradiography, declined by almost 50% in the paraventricular nucleus at 20 mo of age and declined slightly in the organum vasculosum laminae terminalis but did not decline in either the supraoptic nucleus or subfornical organ. Thus the major deficits in fluid intake in aging rats are related to salt appetite; the mechanism was not identified definitively. PMID- 9362311 TI - Use of feces to estimate isotopic abundance in doubly labeled water studies in reindeer in summer and winter. AB - The reliance on samples of blood or urine to estimate isotopic abundance in studies of energy metabolism using the doubly labeled water method has restricted application of the technique to animals that are either tame or easy to catch. This is generally not the case with large, free-ranging wild mammals. The use of feces as a source of body water in which to measure the concentration of isotopic markers was investigated in four female reindeer in summer and in winter. (2)H2O and H2(18)O were injected to approximately 160 parts per million excess. Samples of plasma and feces were then collected simultaneously for up to 456 h. Both isotopes were equilibrated with body water at 8 h postdose. There were no significant differences by animal between dilution spaces, rate constants, rates of CO2 production, and total energy expenditure (TEE) calculated based on samples of plasma or feces in any trial. Mean TEE was 3.557 W/kg (SD 0.907, n = 4) in summer and 1.865 W/kg (SD 0.166, n = 4) in winter. PMID- 9362312 TI - Renal and vascular effects of C-type and atrial natriuretic peptides in humans. AB - C-type natriuretic peptide (CNP) may affect renal and vascular functions differently from atrial natriuretic peptide (ANP). The objective of this study was to compare the renal and vascular actions of CNP to those of ANP in normal men. CNP or ANP (0.005, 0.01, and 0.05 microg x kg(-1) x min(-1)) were given by infusion to eight healthy volunteers. CNP caused dose-dependent increases in natriuresis (U(Na)) and in the fractional excretion of sodium (FE(Na)) with no effect on diuresis (UV), renal plasma flow, and glomerular filtration rate (GFR). Fraction of filtration (FF) increased only with the 0.05 microg x kg(-1) x min( 1) CNP dose. ANP caused larger increases in U(Na), FE(Na), and FF than CNP and also increased UV at 0.01 and 0.05 microg x kg(-1) x min(-1) and GFR at 0.05 microg x kg(-1) x min(-1). Although the ANP and CNP infusions produced similar elevation in the respective peptides plasma levels, urinary and nephrogenous guanosine 3',5'-cyclic monophosphate increased less in response to CNP than to ANP. Blood pressure, forearm blood flow, plasma renin activity, and aldosterone remained unaffected during the peptides infusion. Plasma ANP increased slightly during CNP infusion. Our data indicate a higher threshold of renal response to CNP than to ANP. In contrast to ANP, CNP probably may not act as an endocrine factor in humans. PMID- 9362313 TI - Effects of active vasoconstriction and total flow on perfusion distribution in the rabbit lung. AB - We analyzed the effects of hypoxic vasoconstriction and total flow on the distribution of pulmonary perfusion in 38 isolated left rabbit lungs perfused under zone 3 conditions. Lungs were suspended in an upright position, oriented to the apicobasal line. Distributions of regional perfusion rates (RPR) along the vertical and horizontal axes were determined using nonradioactive microspheres labeled with heavy metal elements, which were detectable with X-ray fluorescence spectrometry. Changing the O2 concentration of a respirator and an extracorporeal membrane oxygenator independently, respective influences of active vasoconstriction induced by alveolar hypoxia and pulmonary artery hypoxia (PA hypoxia) on the RPR distribution were examined at a flow rate of 0.4 ml x min(-1) x g wet lung tissue(-1). To analyze the effects of changes in total flow, we investigated the RPR distribution at a perfusion rate of 1.2 ml x min(-1) x g wet lung tissue(-1). The RPR distribution in the absence of hypoxia was inhomogeneous and was augmented in the lower lung fields, whereas alveolar hypoxia shifted the RPR upward and significantly diminished the RPR in the lung base. RPR distributions along the horizontal axes under alveolar hypoxia conditions demonstrated that remarkable hypoxic pulmonary vasoconstriction (HPV) takes place in medial regions at the lung base. PA hypoxia altered the RPR distribution in qualitatively the same manner as alveolar hypoxia. Increased flow rate augmented the RPR in the lung, except in the dorsobasal region. These results suggest that the occurrence of HPV and the vascular conductance are not uniform throughout the lung. PMID- 9362314 TI - Decreases in arterial pressure activate oxytocin neurons in conscious rats. AB - Hemorrhage and nonhypotensive hypovolemia are known to increase plasma levels of oxytocin (OT) and vasopressin (VP) in rats. The present experiments demonstrated that secretion of OT and VP also are stimulated by acute drug-induced hypotension. Injection of hydralazine abruptly decreased arterial blood pressure in conscious rats and induced Fos expression, a marker of neuronal activation, within OT and VP neurons in the hypothalamus. Hydralazine also elicited substantial increases in plasma levels of both OT and VP. Injection of chlorisondamine similarly elicited acute hypotension and increased plasma levels of OT and VP. Furthermore, when the hypotensive effect of chlorisondamine was blunted by coinfusion of phenylephrine, the induced increases in OT and VP were markedly attenuated. Across all treatments, arterial blood pressure was inversely related to plasma levels of OT and VP. Plasma osmolality was not increased by hydralazine, nor was there evidence of gastric malaise, two known stimuli for OT secretion in rats. These results suggest that arterial hypotension increases neurohypophysial release of OT and VP in conscious rats. PMID- 9362315 TI - Changes in rat sleep after single and repeated injections of the long-acting somatostatin analog octreotide. AB - Somnogenic activity is attributed to both growth hormone (GH) and GH-releasing hormone (GHRH). The aim of our experiments was to study sleep after suppression of the somatotropic axis by means of administration of a long-lasting somatostatin analog, octreotide. Rats received subcutaneous injections of physiological saline (baseline), octreotide (1, 10, and 200 microg/kg), or a control solution just before light onset, and sleep-wake activity and cortical brain temperature were recorded for 23 h. Each dose of octreotide slightly promoted rapid eye movement sleep (REMS) during the 12-h light period. Non-REM sleep (NREMS) was strongly suppressed for 1 h in response to 10 and 200 microg/kg octreotide. This was followed by slight increases in NREMS time and significant enhancements in electroencephalogram slow-wave activity during NREMS after 200 microg/kg octreotide. The octreotide-induced inhibition of the somatotropic axis, as determined by plasma GH levels, vanished by the time sleep increased. Another group of rats received 10 microg/kg octreotide twice a day for 5 days. This treatment elicited persistent decreases in both NREMS time and NREMS intensity. The results support the previously reported REMS-promoting activity of somatostatin in rats. The decreases in sleep after repeated injections of octreotide are attributed to a withdrawal of the normal sleep-promoting activity of GH. The role of GHRH-GH in octreotide-induced acute suppression of NREMS is currently not clear. Other mechanisms, such as mimicking central transmitter functions of somatostatin by octreotide, should also be considered. PMID- 9362317 TI - Angiotensin AT1 receptor blockade fails to attenuate pressure-overload cardiac hypertrophy in fetal sheep. AB - We examined the hypothesis that endogenous angiotensin II and angiotensin type 1 (AT1) receptors participate in the development of fetal right ventricular hypertrophy by studying the effects of AT1 receptor blockade on cardiac growth in fetal sheep subjected to constrictive banding of the pulmonary artery (PA). Seven pairs of twin fetuses were studied beginning at 126 +/- 1 days gestation (term = 145 days). One twin was given losartan (10 mg kg(-1) x day(-1) i.v.) for 7 consecutive days after PA banding, and the other twin served as a saline-treated, PA-banded control. Four additional pairs of twins served as sham-operated controls. Fetal heart rate (HR) and mean arterial blood pressure (MABP) were similar in the two groups of PA-banded animals before treatment and remained unchanged in the PA-banded control group. Losartan resulted in a significant decrease (P < 0.05) in MABP between days 0 and 7, whereas HR was not affected. Total body weight of the losartan-treated animals was significantly less (P < 0.05) than twin PA-banded controls and nonbanded fetuses. Right ventricle weight to-body weight ratios were similar in saline (2.29 +/- 0.34 g/kg) and losartan treated (2.11 +/- 0.15 g/kg) PA-banded animals and significantly greater than that in nonbanded fetuses (1.52 +/- 0.07 g/kg). Similar differences were seen in the right ventricle weight-to-left ventricle weight ratios. Right and left ventricle AT1 receptor mRNA and protein expression were also similar among the three groups, as were AT2 receptor mRNA levels. These data suggest that endogenous angiotensin II does not contribute to the development of pressure overload-induced right ventricular hypertrophy during fetal life and that expression of angiotensin receptors is not altered by increased afterload in the ovine fetus. PMID- 9362316 TI - Lateral hypothalamic injection of GABA(A) antagonist induces gastric vagus mediated hypocalcemia in the rat. AB - The involvement of lateral hypothalamic area (LHA) neurons in the regulation of blood calcium homeostasis was investigated in unanesthetized rats. The microinjection of the gamma-aminobutyric acid A receptor antagonist bicuculline methiodide (BM, 4-40 ng x 0.5 microl(-1) x 5 min(-1)) into the LHA decreased the blood concentration of ionized calcium. Total serum calcium also decreased after the BM injection. This hypocalcemic effect was eliminated by a bilateral vagotomy of the gastric branches. An intravenous injection of atropine methyl bromide (a muscarinic antagonist), nadolol (a beta-adrenergic blocker), or ranitidine (a histamine H2 blocker) suppressed the BM-induced hypocalcemia, whereas phenoxybenzamine (an alpha-adrenergic blocker) proved to be ineffective. Although the intra-LHA injection of BM increased the serum gastrin, which is known to have a hypocalcemic effect, neither secretin nor somatostatin (gastrin-release inhibitors) blocked the hypocalcemic response. These results suggest that the hypocalcemia observed after the excitation of LHA neurons was mediated by muscarinic, beta-adrenergic, and histamine H2 receptors through the gastric vagus. PMID- 9362318 TI - Spontaneously hypertensive rat: cholera toxin converts suppression to immunity through a Th2 cell-IL-4 pathway. AB - The spontaneously hypertensive rat (SHR) exhibits a number of T cell dysfunctions that develop concurrently with elevated blood pressure. Studies have shown a mitogen-induced lymphocyte suppression mediated in part by the production of interferon-gamma (IFN-gamma), which stimulated NO production by macrophages. To assess whether this immune suppression is reversible, SHR were immunized with diphtheria toxoid (DT) with or without cholera toxin (CT) as adjuvant. SHR immunized with DT only displayed weak serum immunoglobulin G (IgG) anti-DT titers, tenfold less than similarly treated normotensive Wistar-Kyoto rats (WKYR). SHR CD4+ T cells failed to proliferate upon in vitro stimulation with DT. In contrast, SHR coimmunized with DT and CT showed serum IgG antibody titers similar to WKYR and Brown Norway rats. Coimmunization with CT rescued SHR CD4+ T cells from suppression and supported DT- or B subunit of CT-specific proliferative responses, and these cells produced more interleukin-4 (IL-4) than IFN-gamma, and anti-IFN-gamma antibody treatment enhanced IL-4 production. Exogenous IL-4 increased the proliferation of antigen-specific CD4+ T cells, whereas IFN-gamma was inhibitory. This study shows that the adjuvant CT induces T helper 2-type responses, reversing the T cell dysfunction in the SHR. PMID- 9362320 TI - Lack of cross tolerance between LPS and muramyl dipeptide in induction of circulating TNF-alpha and IL-6 in guinea pigs. AB - In guinea pigs, lipopolysaccharide (LPS) from gram-negative bacteria and muramyl dipeptide (MDP) from gram-positive bacteria are potent inducers of systemic production of proinflammatory cytokines and fever. However, there is a striking difference between these two bacterial pyrogens in so far as repeated administration of LPS, but not of MDP, in short-term intervals induces tolerance by a progressive downregulation of the systemic cytokine network. In the present study, we investigated MDP-induced fever and the systemic release of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in LPS-tolerant guinea pigs in comparison with naive animals. Endotoxin tolerance was induced by repeated intramuscular injections of 20 microg/kg LPS at intervals of 3 days. In response to the last of five injections with LPS, systemic production of TNF alpha and IL-6 as well as the development of a febrile response was abrogated almost completely. Those guinea pigs that had developed an LPS tolerance could, however, produce the same amounts of TNF-alpha and IL-6 as naive animals in response to a challenge with MDP. Also, MDP-induced fever was identical in LPS tolerant and naive guinea pigs. These results provide evidence for a lack of cross tolerance between LPS and MDP in induction of circulating cytokines and fever in guinea pigs. PMID- 9362319 TI - Microvillous membrane potential (Em) in villi from first trimester human placenta: comparison to Em at term. AB - The microvillous membrane (MVM) potential (Em) of first trimester human placental villi was measured and compared with that in villi from term human placentas. The median Em in first trimester villi (-28 mV) was significantly more negative than that at term (-21 mV; P < 0.001). The median Em measured in villi from early (weeks 6-11) first trimester (-32 mV) was significantly more negative than that in late (weeks 12 and 13) first trimester villi (-24 mV; P < 0.001). Elevating extracellular KCl concentration induced a significant depolarization of Em in both first trimester and term villi (P < 0.05 and P < 0.001, respectively). The magnitude of this depolarization was greater in first trimester than at term, indicating that the ion conductance of the MVM changes with gestation. Exposure to ouabain induced a significant depolarization of Em (3 mV: P < 0.05) in first trimester villi but had little effect at term. These results suggest that microvillous membrane electrophysiology changes with placental development. An alteration in the relative K+:Cl- conductance of the MVM is likely to be a major contributor to the change in the magnitude of Em. PMID- 9362321 TI - Fat accretion and the regulation of insulin-mediated glycogen synthesis after puberty in rats. AB - Peripheral insulin sensitivity decreases after puberty in both humans and rodents and can be explained mostly by a reduction in insulin-mediated glycogen synthesis. We tested the hypothesis that the increase in postpubertal fat mass (FM), reflecting an alternative energy store, regulates a decrease in the capacity to store muscle glycogen. We studied Sprague-Dawley rats (n = 21) before puberty (Pre) or after puberty (at 4 mo of age) in groups that were either ad libitum fed (Post) or moderately caloric restricted (CR). FM (by 3H2O isotope dilution technique) was decreased by >40% in CR compared with Post. Glucose uptake (Rd, by 18 mU x kg(-1) x min(-1) hyperinsulinemic clamp) was 63 +/- 8 mg x kg(-1) x min(-1) in Pre and decreased to 39 +/- 2 mg x kg(-1) x min(-1) in Post (P < 0.001). However, it increased in CR to 53 +/- 2 mg x kg(-1) x min(-1) (P < 0.001 vs. Post). This increase in Rd was mainly accounted for by an increase in glycogen synthesis (Rd glycolysis determined by the rate of conversion of 3H labeled glucose to 3H2O) from 23 +/- 2 in Post to 33 +/- 2 mg x kg(-1) x min(-1) in CR (P < 0.001; 38 +/- 7 mg x kg(-1) x min(-1) in Pre). Correction of glycogen synthesis in CR to near-prepubertal levels was further supported by directly assayed muscle glycogen content after insulin stimulation that was 45% higher and by a 35% enhanced accumulation of [3H]glucose into glycogen. No changes in the enzyme kinetics of glycogen synthase or phosphorylase were observed. An additional group of 2-mo-old postpubertal ad libitum-fed rats was matched with CR for lean body mass but had more FM. This group demonstrated 25% lower rates of insulin-mediated glycogen synthesis compared with CR, further supporting the notion that a moderate reduction of FM prevents the decline in insulin responsiveness and glycogen synthesis occurring after puberty. These data suggest a cause-effect relationship between the increased deposition of fat and the reduced ability to store glucose in skeletal muscle after puberty. PMID- 9362322 TI - Melatonin attenuates photic disruption of circadian rhythms in Siberian hamsters. AB - Body temperature (Tb) was recorded via a biotelemetry system from 28 adult male Siberian hamsters maintained in a light-dark (LD) cycle of 16 h light/day for several months. After Tb was recorded for 3 wk, the LD cycle was phase delayed by extending the light phase by 5 h for 1 day; animals remained on a 16:8 LD cycle for the remainder of the experiment. Hamsters were injected daily with melatonin or vehicle solution for several weeks, beginning either 2 mo after (experiment 1) or on the day of (experiment 2) the phase shift; injections occurred within 30 min of dark onset. In experiment 1, 75% of animals free ran with circadian periods >24 h, beginning on the day of the phase shift, and never reentrained to the LD cycle; no hamsters unambiguously entrained to daily injections. In contrast, 78% of animals in experiment 2 entrained to melatonin injections, and 71% of those animals subsequently reentrained to the photocycle when the injection regimen ended. No vehicle-treated animals entrained to the injection schedule. Melatonin had no effect on daily mean Tb and Tb rhythm amplitude in either experiment; however, melatonin doubled the duration of a hyperthermic response that occurred after each injection. Thus melatonin can prevent loss of entrainment induced by a phase shift of the LD cycle but cannot restore entrainment to free-running animals. Failure to reentrain in the presence of two appropriately coordinated entraining agents also suggests that a phase shift of the photocycle can diminish the sensitivity of the circadian system to both photic and nonphotic input. PMID- 9362323 TI - Relations between functional, inflammatory, and degenerative parameters during adjuvant arthritis in rats. AB - We assessed the time-course of adjuvant arthritis (AA) in Lewis rats, using biotelemetry to monitor the rat's spontaneous locomotor activity and body temperature, and studied the evolution of the arthritic index, circulating concentrations of inflammation-promoting cytokines, cartilage proteoglycan synthesis, and the effect of indomethacin as a cyclooxygenase inhibitor to evaluate prostaglandin (PG) contribution in AA. The injection of complete Freund's adjuvant on day 0 (D0) induced a marked, transient loss of locomotor activity (D1-D4; initial phase) and then a second phase of hypomobility peaking on D15 and thereafter irreversible (D16-D20; arthritic phase). Fever peaked first on D1 and again between D13 and D17. The primary hyperthermia was associated with increases in plasma interleukin-6 and tumor necrosis factor-alpha concentrations and seemed to be partly PG dependent. Proteoglycan synthesis inhibition in the patellar cartilage increased gradually, spreading from the injected paw to the contralateral paw. It was corrected on D20 by preventive and curative indomethacin treatments. Indomethacin also greatly relieved hypomobility during the systemic phase of AA (D10-D15). The combination of information about cartilage metabolism, body temperature, locomotor activity, and cytokine in this study permits analysis of analgesic, antipyretic, anti-inflammatory, and chondroprotective properties of drugs in the various phases of AA. Thus, using a new methodology, we have discriminated the different phases of the disease and confirmed the symptomatic and systemic inhibitory effect of indomethacin on fever, activity, and cartilage metabolism. PMID- 9362324 TI - Increase in muscle IGF-I protein but not IGF-I mRNA after 5 days of endurance training in young rats. AB - Five days of treadmill training in rats leads to increased muscle size and running time. This was used to examine the effect of exercise on circulating insulin-like growth factor I [IGF-I; radioimmunoassay (RIA)], local muscle (hindlimb) IGF-I (by RIA), and muscle IGF-I mRNA (by ribonuclease protection assay). Eight-week-old female Sprague-Dawley rats were divided into three groups: control (n = 10); single-exercise test (n = 10), untrained but with one maximal exercise test at the end of the study; and training (n = 16), trained for 5 days and one maximal exercise test on day 6. There were no differences among the groups with respect to circulating IGF-I. Muscle IGF-I protein in trained rats (4.2 +/- 1.5 ng/g of muscle tissue) was significantly greater than both control (0.27 +/- 0.1 ng/g) and single-exercise test (0.62 +/- 0.19 ng/g, P < 0.05 by analysis of variance). There was no difference among the groups in IGF-I mRNA gene expression. These data suggest that there is an early, marked, local muscle increase in IGF-I protein in response to exercise. This increase, however, may not be related to increased muscle IGF-I gene expression. Moreover, the IGF-I response was probably local in nature since it was not matched by any increase in circulating IGF-I. PMID- 9362325 TI - Lysosomal proteolysis in distally or proximally denervated rat soleus muscle. AB - We examined the mechanism of accelerated proteolysis in denervated rat soleus muscles. The soleus was denervated by severing either the tibial nerve (proximal, short stump) or sciatic nerve (distal, long stump) at 24, 48, 72, or 96 h before excision. Twenty-four hours after denervation, the extent of atrophy was similar for proximal and distal denervation, although lysosomal latency declined in both groups. After 48 and 72 h, denervation resulted in a decline in protein content, an increase in in vitro protein degradation, and a decline in lysosomal latency, all of which were greater in proximally denervated than in contralateral distally denervated muscles. These differences between acute responses of proximally and distally denervated muscles suggest the retention of some factor in the longer nerve stump that attenuates atrophy. After 96 h, total protein loss, protein degradation, and lysosomal latency were similar for proximal and distal denervation, suggesting the loss of axoplasmic flow from the long nerve stump. PMID- 9362326 TI - Positional cloning of the PEX gene: new insights into the pathophysiology of X linked hypophosphatemic rickets. AB - X-linked hypophosphatemic rickets (HYP) is the most common form of hereditary renal phosphate wasting. The hallmarks of this disease are isolated renal phosphate wasting with inappropriately normal calcitriol concentrations and a mineralization defect in bone. Studies in the Hyp mouse, one of the murine models of the human disease, suggest that there is an approximately 50% decrease in both message and protein of NPT-2, the predominant sodium-phosphate cotransporter in the proximal tubule. However, human NPT-2 maps to chromosome 5q35, indicating that it is not the disease gene. Positional cloning studies have led to the identification of a gene, PEX, which is responsible for the disorder. Further studies have led to identification of the murine Pex gene, which is mutated in the murine models of the disorder. These studies, in concert with other studies, have led to improved understanding of the pathophysiology of HYP and a new appreciation for the complexity of normal phosphate homeostasis. PMID- 9362327 TI - Differential activities of H+ extrusion systems in MDCK cells due to extracellular osmolality and pH. AB - The aim of the present study was to obtain detailed information on MDCK cell proton secretion characteristics under various growth conditions. Confluent monolayers cultured on glass coverslips were adapted over 48 h to media with different osmolality and pH (200 mosmol/kgH2O, pH 7.4; 300 mosmol/kgH2O, pH 7.4; and 600 mosmol/kgH2O, pH 6.8) corresponding to the luminal fluid composition of the collecting duct segments found in the in renal cortex, the outer stripe of outer medulla and inner medulla. Proton fluxes were determined from the recovery of intracellular pH following an acid load induced by an NH4Cl pulse times the corresponding intrinsic buffering power (beta(i)). The intracellular buffering power was found to change only with culture medium osmolality but not with culture medium pH. In addition to an amiloride and Hoe-694-sensitive Na+/H+ exchange, Madin-Darby canine kidney (MDCK) cells possess a Sch-28080-sensitive, K+-dependent H+ extrusion mechanism that is increased upon adaptation of monolayers to hyperosmotic-acidic culture conditions. A significant contribution of the bafilomycin A1-sensitive vacuolar H+-ATPase could be found only in cells adapted to hyposmotic culture conditions. Exposure of MDCK cells to 10(-5) or 10( 7) M aldosterone for either 1 or 18 h did not alter the H+ extrusion characteristics significantly. The results obtained show that different extracellular osmolality and pH induce different MDCK phenotypes with respect to their H+-secreting systems. PMID- 9362328 TI - PGE2-mediated cytoprotection in renal epithelial cells: evidence for a pharmacologically distinct receptor. AB - Although the exact mechanism of prostaglandin E2 (PGE2)-mediated cytoprotection has not been elucidated, its ability to induce cytoprotection in cell culture suggests this action occurs at the cellular level. The present studies were conducted to determine whether PGE2 induces protection against 2,3,5 (trisglutathion-S-yl)-hydroquinone [2,3,5-(trisglutathion-S-yl)-HQ]-mediated cytotoxicity in a renal proximal tubule epithelial cell line (LLC-PK1) and to delineate the cellular and molecular mechanisms associated with this response. Pretreatment of LLC-PK1 cells with 0.01-40 microM PGE2 for 24 h fully protects against a moderately toxic concentration of 2,3,5-(trisglutathion-S-yl)-HQ. PGE2 mediated cytoprotection is observed in cells pretreated at pH 7.4 but not at pH 7.8. However, cytoprotection is observed in LLC-PK1 cells pretreated with the PGE2 analog, 11-deoxy-16,16-dimethyl PGE2 (DDM-PGE2) but not with the PGE2 receptor [E-prostanoid (EP)] agonists 17-phenyltrinor PGE2 (EP1), 11-deoxy PGE1 (EP2/EP4), sulprostone (EP1/EP3), PGE1, or PGA2. 12-O-tetradecanoylphorbol-13 acetate (TPA), a potent activator of protein kinase C (PKC), also induces cytoprotection, supporting a role for this pathway in the cytoprotective response. PGE2, DDM-PGE2, and TPA all induce the binding of nuclear proteins to a TPA responsive element (TRE), whereas analogs that did not induce cytoprotection (PGE1, 17-phenyltrinor PGE2, sulprostone) were without effect. DDM-PGE2- and TPA mediated cytoprotection and TRE binding activity are inhibited by N-(2[[3-(4 bromophenyl)-2-propenyl]-amino]-ethyl)-5-isoquinolinesulfonam ide (H-89), a PKC inhibitor. These data suggest that cytoprotection by PGE2 and DDM-PGE2 in LLC-PK1 cells is mediated by a PKC-coupled receptor, which is pharmacologically distinct from the presently classified EP receptor subtypes. PMID- 9362329 TI - A conserved cytoplasmic region of ROMK modulates pH sensitivity, conductance, and gating. AB - ROMK channels play a key role in overall K balance by controlling K secretion across the apical membrane of mammalian cortical collecting tubule. In contrast to the family of strong inward rectifiers (IRKs), ROMK channels are markedly sensitive to intracellular pH. Using Xenopus oocytes, we have confirmed this pH sensitivity at both the single-channel and whole cell level. Reduction of oocyte pH from 6.8 to 6.4 (using a permeant acetate buffer) reduced channel open probability from 0.76 +/- 0.02 to near zero (n = 8), without altering single channel conductance. This was due to the appearance of a long-lived closed state at low internal pH. We have confirmed that a lysine residue (K61 on ROMK2; K80 on ROMK1), NH2 terminal to the first putative transmembrane segment (M1), is primarily responsible for conferring a steep pH sensitivity to ROMK (B. Fakler, J. Schultz, J. Yang, U. Schulte, U. Braandle, H. P. Zenner, L. Y. Jan, and J. P. Ruppersberg. EMBO J. 15: 4093-4099, 1996). However, the apparent pKa of ROMK also depends on another residue in a highly conserved, mildly hydrophobic area: T51 on ROMK2 (T70 on ROMK1). Replacing this neutral threonine (T51) with a negatively charged glutamate shifted the apparent pKa for inward conductance from 6.5 +/- 0.01 (n = 8, wild type) to 7.0 +/- 0.02 (n = 5, T51E). On the other hand, replacing T51 with a positively charged lysine shifted the apparent pKa in the opposite direction, from 6.5 +/- 0.01 (n = 8, wild type) to 6.0 +/- 0.02 (n = 9, T51K). The opposite effects of the glutamate and lysine substitutions at position 51 (ROMK2) are consistent with a model in which T51 is physically close to K61 and alters either the local pH or the apparent pKa via an electrostatic mechanism. In addition to its effects on pH sensitivity, the mutation T51E also decreased single-channel conductance from 34.0 +/- 1.0 pS (n = 8, wild type) to 17.4 +/- 1 pS (n = 9, T51E), reversed the voltage gating of the channel, and significantly increased open-channel noise. These effects on single-channel currents suggest that the T51 residue, located in a mildly hydrophobic area of ROMK2, also interacts with the hydrophobic region of the permeation pathway. PMID- 9362330 TI - Heat shock-induced protection and enhancement of Na+-glucose cotransport by LLC PK1 monolayers. AB - Monolayers of the porcine-derived renal epithelial cell line, LLC-PK1, were used to characterize the effects of heat stress on Na+-glucose cotransport. Transepithelial current dependent on 5 mM glucose (I(Glc)), phloridzin-sensitive current (I(phz)), and total transepithelial current (I(total)) were measured as indicators of Na+-glucose cotransport. Severe heat shock (SHS; 45 degrees C for 1 h, then 37 degrees C for measurements) decreased transepithelial electrical resistance (TER), I(Glc), I(phz), and I(total) 50-70%. Mild heat shock (MHS; 42 degrees C for 3 h, then 37 degrees C for 12 h) induced accumulation of 72-kDa heat shock protein (HSP-72), decreased damage to TER from SHS, and prevented damage to I(Glc), I(phz), and I(total). Kinetic analysis showed that SHS damaged and MHS protected total Na+-glucose transport capacity (Vmax of I(Glc)). MHS alone increased TER (50%), I(Glc) (20%), I(total) (20%), and Vmax of I(Glc) (25%). On enhancement of the Na+ gradient by depletion of intracellular Na+, MHS increased I(Glc) 50% and had no effect on transepithelial Na+-dependent sulfate reabsorptive flux measured concurrently or in Na+-replete tissues. These effects of MHS were not reflected in effects on cell survival or luminal membrane surface area as indicated by lactate dehydrogenase or alkaline phosphatase release. In conclusion, HSP-72-inducing heat treatment both protected and enhanced Na+ glucose cotransport independently of the luminal membrane Na+ gradient and selectively with respect to effects on TER, reabsorptive sulfate transport, cell survival, and luminal membrane surface area. PMID- 9362331 TI - Cyclooxygenase-2 is expressed in bladder during fetal development and stimulated by outlet obstruction. AB - Studies were undertaken to assess expression of inducible cyclooxygenase (COX)-2 in bladder during fetal development and COX-1 and COX-2 expression after outlet obstruction. Bladder tissue or bladder progenitor tissue was harvested from CD-1 murine embryos at embryonic days 11.5 (E11.5), E14.5, E17.5, E20.5 (newborn), and from adult. Bladder obstruction was created in adult female mice by ligating the urethra, and bladders were harvested after 3-24 h of obstruction. Gene expression was assessed by semiquantitative reverse transcription-polymerase chain reaction and Western blotting. COX-2 was highly expressed at the early stages of bladder development and declined progressively throughout gestation. In adult bladder, both COX-1 and COX-2 were detectable at low levels under basal conditions. An approximately 30-fold increase in COX-2 mRNA was seen after 24 h of obstruction. In contrast, COX-1 did not change with obstruction. COX-2 mRNA levels peaked at 6 h of obstruction. In regional bladder-distention models, COX-2 induction was confined to the area of distention. Bladder outlet obstruction stimulates COX-2 expression dramatically, reactivating a gene that is highly expressed during fetal development. PMID- 9362332 TI - Peptide YY receptor distribution and subtype in the kidney: effect on renal hemodynamics and function in rats. AB - This study characterizes the location and subtype of peptide YY (PYY) receptors in rat and rabbit kidney and the effect of PYY on renal function and renal hemodynamics in rats. Receptor autoradiography performed on kidney sections revealed a dense concentration of specific high-affinity binding sites [dissociation constant (Kd) = 0.7 +/- 0.1 nM] in the papilla of the rat, as well as cortical and papillary binding in the rabbit (papilla, Kd = 1.6 +/- 0.6 nM) and some medullary binding in both species. In the rat papilla, neuropeptide Y (NPY) and the Y1 agonist [Leu31,Pro34]NPY competed with PYY for binding (Kd = 1.1 +/- 0.4 nM and 1.6 +/- 0.5 nM, respectively), but NPY-(13-36) (Y2 agonist) and pancreatic polypeptide (PP, Y4 agonist) were without effect, demonstrating that the PYY receptor in the rat papilla is of the Y1 subtype. In the rabbit papilla, NPY and NPY-(13-36) competed with PYY (Kd = 0.5 +/- 0.1 and 3.1 +/- 0.6 nM, respectively), but [Leu31,Pro34]NPY and PP were without effect, evidence that the PYY receptor in the rabbit papilla is of the Y2 subtype. Infusion of PYY into rats (47 pmol x kg(-1) x min[-1]) increased mean arterial pressure (103 +/- 6 to 123 +/- 8 mmHg) and decreased renal plasma flow (13 +/- 1.8 to 8.4 +/- 2.1 ml/min) but produced no significant change in glomerular filtration rate or sodium excretion. Injection of PYY or angiotensin II directly into the renal artery caused a dose-related vasoconstriction, which was less intense but of longer duration for PYY than for angiotensin II. These results show that receptors for PYY are widely distributed in the kidney and that exogenously administered PYY causes renal vasoconstriction and may influence renal sodium excretion. PMID- 9362333 TI - Apical ANG II-stimulated PLA2 activity and Na+ flux: a potential role for Ca2+ independent PLA2. AB - Type 1 angiotensin II (ANG II) receptors (AT1R), which mediate proximal tubule (PT) salt and water reabsorption, undergo endocytosis and recycling. Prior studies in a PT-like model (LLC-PKcl4 cells expressing rabbit AT1R) (LLC-PK-AT1R cells) determined that quinacrine, a nonspecific phospholipase A2 (PLA2) inhibitor, and the haloenol lactone suicide substrate (HELSS), a Ca2+-independent PLA2 inhibitor, attenuated apical (AP) AT1R recycling. Further studies were undertaken to examine the association between AT1R endocytotic movement and PLA2 activity in this model. AP ANG II (100 nM) increased [3H]arachidonic acid ([3H]AA) release 4.4 +/- 0.38-fold in LLC-PK-AT1R cells cultured on permeable supports. Basolateral (BL) ANG II had no significant effect. Reversed-phase high performance liquid chromatography confirmed that AP ANG II stimulated free [3H]AA release. Quinacrine, HELSS, and palmitoyl trifluoromethyl ketone, another Ca2+ independent PLA2 inhibitor, inhibited AP ANG II-stimulated [3H]AA release, as did inhibiting AP AT1R internalization with phenylarsine oxide. The role of HELSS inhibitable AA release in ANG II-mediated 22Na flux was examined, given the effects of AT1R-mediated PLA2 activity on salt and water reabsorption. AP ANG II (100 nM) stimulated 22Na flux (AP--> BL), a response inhibited by HELSS. Thus, in this model, AP AT1R activated PLA2 with concomitant 22Na flux (AP --> BL), suggesting a link between AP AT1R endocytotic movement, AT1R-stimulated PLA2 activity, and 22Na flux in this model. The effects of HELSS suggest that Ca2+ independent PLA2 activity may be involved in this AP ANG II response. PMID- 9362335 TI - Lysophosphatidic acid: a novel growth and survival factor for renal proximal tubular cells. AB - Lysophosphatidic acid (LPA) is the smallest and structurally simplest of all glycerophospholipids. LPA is a normal constituent of serum and binds with high affinity to albumin while retaining its biological activity. The effects of LPA are pleiotropic and range from mitogenesis to stress fiber formation. In this report, we demonstrate two novel functions for LPA. LPA acts as a survival factor to inhibit apoptosis of primary cultures of mouse renal proximal tubular (MPT) cells. LPA also acts as a potent mitogen for MPT cells. The ability of LPA to act as both a survival factor and a mitogen is mediated by the lipid kinase phosphatidylinositol 3-kinase (PI3K), since these activities were completely blocked by wortmannin or LY-294002, two structurally dissimilar inhibitors of PI3K. The identification of LPA as a proliferative and anti-apoptotic factor suggests a potential role for this lipid mediator during the injury and/or recovery phases following tubular damage. PMID- 9362334 TI - Early role of Fsp1 in epithelial-mesenchymal transformation. AB - A seamless plasticity exists among cells shifting between epithelial and mesenchymal phenotypes during early development and again later, in adult tissues, following wound repair or organ remodeling in response to injury. Fsp1, a gene encoding a fibroblast-specific protein associated with mesenchymal cell morphology and motility, is expressed during epithelial-mesenchymal transformations (EMT) in vivo. In the current study, we identified several cytokines that induce Fsp1 in cultured epithelial cells. A combination of these factors, however, was most efficacious at completing the process of EMT. The optimal combination identified were two of the cytokines classically associated with fibrosis, i.e., transforming growth factor-beta1 (TGF-beta1) and epidermal growth factor (EGF). To confirm that it was the induction of Fsp1 by these cytokines mediating EMT, we used antisense oligomers to block Fsp1 production and subsequently measured cell motility and markers of EMT phenotype. The antisense oligomers suppressed Fsp1 expresison and epithelial transformation; therefore, we conclude that the appearance of Fsp1 is an important early event in the pathway toward EMT. PMID- 9362336 TI - Endothelin-1 increases rat distal tubule acidification in vivo. AB - Because endothelin receptor inhibition blunts increased distal tubule acidification induced by dietary acid, we examined whether endothelin-1 (ET-1) increases acidification of in vivo perfused distal tubules of anesthetized rats. ET-1 was infused intraaortically (1.4 pmol x kg(-1) x min[-1]) into control animals and into those with increased distal tubule HCO3 secretion induced by drinking 80 mM NaHCO3 solution for 7-10 days. ET-1 increased distal tubule acidification in both control and NaHCO3 animals. Increased acidification in control animals was mediated by increased distal tubule H+ secretion (23.7+/-2.2 vs. 18.7 +/- 1.7 pmol x mm(-1) x min(-1), P < 0.05) with no changes in HCO3 secretion. By contrast, ET-1 increased distal tubule acidification in NaHCO3 animals predominantly by decreasing HCO3 secretion (-9.5 +/- 1.0 vs. -18.7 +/-1.8 pmol x mm(-1) x min(-1), P < 0.001) with less influence on H+ secretion. When indomethacin was infused (83 microg x kg(-1) x min[-1]) to inhibit synthesis of prostacyclin, an agent previously shown to increase HCO3 secretion in the distal tubule, ET-1 increased distal tubule H+ secretion in both control (24.3 +/-2.2 vs. 15.7 +/- 1.6 pmol x mm(-1) x min(-1), P < 0.02) and NaHCO3 (20.0 +/- 2.0 vs. 13.6 +/- 1.4 pmol x mm(-1) x min(-1), P < 0.05) without affecting HCO3 secretion. The data show that ET-1 increases distal tubule acidification in vivo and can do so by increasing H+ secretion and by decreasing HCO3 secretion when the latter is augmented by dietary NaHCO3. PMID- 9362337 TI - Effect of luminal angiotensin II on rabbit proximal convoluted tubule bicarbonate absorption. AB - The present in vitro microperfusion study examined the effect of luminal angiotensin II on proximal convoluted tubule (PCT) volume absorption and bicarbonate transport. Neither 10(-11) M, 10(-10) M, nor 2 x 10(-8) M luminal angiotensin II significantly affected PCT transport. When tubules were first perfused with enalaprilat to inhibit endogenous angiotensin II production, addition of 10(-10) M luminal angiotensin II increased volume absorption (0.72 +/ 0.08 vs. 0.86 +/- 0.07 nl x mm(-1) xmin(-1), P < 0.01) and bicarbonate transport (52.3 +/- 3.7 vs. 67.9 +/- 4.2 pmol x mm(-1) min(-1), P < 0.01). Addition of 10( 6) M losartan, an AT1 inhibitor, to the luminal perfusate inhibited volume absorption (0.95 +/- 0.14 vs. 0.72 +/- 0.11 nl x mm(-1) x min(-1), P < 0.05) and bicarbonate transport (65.0 +/- 7.3 vs. 54.7 +/- 9.2 pmol x mm(-1) x min(-1), P < 0.05). Addition of 10(-4) M luminal PD-123319, an AT2 inhibitor, was without effect. In tubules perfused with 10(-4) M luminal enalaprilat and 10(-4) M luminal PD-123319, addition of 10(-10) M luminal angiotensin II in the experimental period resulted in a stimulation in volume absorption (0.61 +/- 0.08 vs. 0.81 +/- 0.10 nl x mm(-1) x min(-1), P < 0.01) and bicarbonate transport (49.9 +/- 6.3 vs. 77.4 +/- 14.3 pmol x mm(-1) x min(-1), P < 0.01). In tubules perfused with 10(-6) M losartan and 10(-4) M enalaprilat, addition of luminal 10( 10) M angiotensin II resulted in no change in transport. These data are consistent with endogenous angiotensin II affecting PCT bicarbonate transport in vitro via luminal AT1 receptors. PMID- 9362338 TI - Immunolocalization of AE2 anion exchanger in rat kidney. AB - The cellular and subcellular localizations of the AE2 anion exchanger in rat kidney have remained elusive despite detection of moderately abundant AE2 mRNA and AE2 polypeptide in all kidney regions. In this report a simple epitope unmasking technique has allowed the immunolocalization of AE2 antigenic sites in basolateral membranes of several rat kidney tubular epithelial cells. AE2 immunostaining was faint or absent in the glomerulus and proximal tubule, present in descending and ascending thin limbs, and stronger in the medullary thick ascending limb (MTAL). A lower staining intensity was found in cortical thick ascending limbs and even less in the distal convoluted tubule. In contrast, there was an enhanced staining in the macula densa. In principal cells (PC) of the connecting segment, AE2 was undetectable but gradually increased in intensity along the collecting duct, with strongest staining in inner medullary collecting duct (IMCD) PC. A sodium dodecyl sulfate-sensitive AE2-related Golgi epitope was also detected in some interstitial and endothelial cells of the inner medulla and in epithelial cells of IMCD and MTAL. Colchicine treatment of the intact animal altered the distribution of this Golgi-associated epitope but left plasmalemmal AE2 undisturbed. Reverse transcription-polymerase chain reaction detected AE2a, AE2b, and AE2c2 but not AE2cl transcripts in rat kidney mRNA. The results suggest a widespread occurrence of the AE2 protein in several renal epithelial cell types. PMID- 9362340 TI - Nonlinear filter properties of the thick ascending limb. AB - A mathematical model was used to investigate the filter properties of the thick ascending limb (TAL), that is, the response of TAL luminal NaCl concentration to oscillations in tubular fluid flow. For the special case of no transtubular NaCl backleak and for spatially homogeneous transport parameters, the model predicts that NaCl concentration in intratubular fluid at each location along the TAL depends only on the fluid transit time up the TAL to that location. This exact mathematical result has four important consequences: 1) when a sinusoidal component is added to steady-state TAL flow, the NaCl concentration at the macula densa (MD) undergoes oscillations that are bounded by a range interval envelope with magnitude that decreases as a function of oscillatory frequency; 2) the frequency response within the range envelope exhibits nodes at those frequencies where the oscillatory flow has a transit time to the MD that equals the steady state fluid transit time (this nodal structure arises from the establishment of standing waves in luminal concentration, relative to the steady-state concentration profile, along the length of the TAL); 3) for any dynamically changing but positive TAL flow rate, the luminal TAL NaCl concentration profile along the TAL decreases monotonically as a function of TAL length; and 4) sinusoidal oscillations in TAL flow, except at nodal frequencies, result in nonsinusoidal oscillations in NaCl concentration at the MD. Numerical calculations that include NaCl backleak exhibit solutions with these same four properties. For parameters in the physiological range, the first few nodes in the frequency response curve are separated by antinodes of significant amplitude, and the nodes arise at frequencies well below the frequency of respiration in rat. Therefore, the nodal structure and nonsinusoidal oscillations should be detectable in experiments, and they may influence the dynamic behavior of the tubuloglomerular feedback system. PMID- 9362339 TI - Cloning and characterization of maxi K+ channel alpha-subunit in rabbit kidney. AB - We have identified in rabbit renal cells two alternatively spliced transcripts of the alpha-subunit rbslo1 and rbslo2. Rbslo1 has a novel "in-frame" 174-bp insertion immediately after the predicted S8 transmembrane segment, whereas rbslo2 has a 104-bp deletion between S9 and S10, creating a frameshift and a premature termination codon. Amino acid identity between mouse maxi K- channel alpha-subunit (mslo) and rbslol was 99%. Two transcript sizes of 4.2 and 7.5 kb were detected in brain, kidney, stomach, testis, and lung. Rbslo is expressed in glomeruli, thin limbs of Henle's loop, medullary and cortical thick ascending limbs of Henle's loop, and cortical, outer, and inner medullary collecting ducts; however, it was rarely detected in proximal convoluted tubules. Rbslo1 is most abundant in inner medulla. Expressed in Xenopus oocytes, rbslo1 generates depolarization-activated, outwardly rectifying K+ currents. Rbslo1 expressed in Chinese hamster ovary cells could be activated by depolarization and Ca2+. These data suggest that rbslo transcripts are expressed in multiple nephron segments and that the magnitude of mRNA expression varies among different nephron segments. PMID- 9362341 TI - Spectral properties of the tubuloglomerular feedback system. AB - A simple mathematical model was used to investigate the spectral properties of the tubuloglomerular feedback (TGF) system. A perturbation, consisting of small amplitude broad-band forcing, was applied to simulated thick ascending limb (TAL) flow, and the resulting spectral response of the TGF pathway was assessed by computing a power spectrum from resulting TGF-regulated TAL flow. Power spectra were computed for both open- and closed-feedback-loop cases. Open-feedback-loop power spectra are consistent with a mathematical analysis that predicts a nodal pattern in TAL frequency response, with nodes corresponding to frequencies where oscillatory flow has a TAL transit time that equals the steady-state fluid transit time. Closed-feedback-loop spectra are dominated by the open-loop spectral response, provided that gamma, the magnitude of feedback gain, is less than the critical value gamma c required for emergence of a sustained TGF mediated oscillation. For gamma exceeding gamma c, closed-loop spectra have peaks corresponding to the fundamental frequency of the TGF-mediated oscillation and its harmonics. The harmonics, expressed in a nonsinusoidal waveform for tubular flow, are introduced by nonlinear elements of the TGF pathway, notably TAL transit time and the TGF response curve. The effect of transit time on the flow waveform leads to crests that are broader than troughs and to an asymmetry in the magnitudes of increasing and decreasing slopes. For feedback gain magnitude that is sufficiently large, the TGF response curve tends to give a square waveshape to the waveform. Published waveforms and power spectra of in vivo TGF oscillations have features consistent with the predictions of this analysis. PMID- 9362342 TI - A simplified method for isolation of large numbers of defined nephron segments. AB - We describe a simplified method for the isolation of large numbers of nephron segments from rat and rabbit kidneys. In contrast to most previous protocols, the kidneys are not perfused. After removal from the animal, the kidney is sliced and torn in pieces that are subsequently digested in culture medium containing 0.5 mg/ml of collagenase at 37 degrees C. If the preparation is agitated only very gently and infrequently, then the tissue gradually falls apart into a suspension containing long nephron fragments, often consisting of multiple connected segments. These are easily sorted into homogeneous segment populations that can be used for enzyme assays, protein extraction for immunoblotting, and RNA extraction for reverse transcription-polymerase chain reaction, all of which have been done successfully in our laboratory. For comparison, we have also examined cortical collecting tubule segments and cells prepared by the more rigorous protocol described previously (E. Schlatter, U. Frobe, and R. Greger. Pflugers Arch. 421: 381-387, 1992). Even after the isolation of single cells in a Ca2+ free medium, the cells maintain their normal architecture and a distinct separation of apical and basolateral membranes. PMID- 9362343 TI - Simultaneous recording of tissue ion content and blood flow in rat renal medulla: evidence on interdependence. AB - The relationship of renal medullary tissue ion concentration and medullary blood flow (MBF) has never been closely evaluated because of limitations of available measuring methods. In an attempt to overcome this difficulty, an integrated probe was developed for simultaneous recording in rat renal medulla of tissue electrical admittance (Y), an index of interstitial ion concentration, and tissue perfusion with blood (laser-Doppler method). During spontaneous-selective MBF variations tissue Y showed inverse changes (r = -0.77, P < 0.001). The inverse correlation of the two variables was also seen after MBF has been reduced (-43%) by indomethacin, 5 mg/kg body wt iv (r = -0.77, P < 0.01). A modest selective MBF reduction (15%) induced by glibenclamide, an inhibitor of ATP-dependent K channels, did not alter medullary tissue admittance. The data support experimentally the concept that the rate of medullary tissue perfusion with blood is one determinant of interstitial solute concentration; however, changes in the latter were demonstrable only with major alterations of the MBF. PMID- 9362344 TI - Cloning and localization of a double-pore K channel, KCNK1: exclusive expression in distal nephron segments. AB - The K-selective channel, TOK1, recently identified in yeast, displays the unusual structural feature of having two putative pore regions, in contrast to all previously cloned K channels. Using the TOK1 pore regions as probes, we identified a human kidney cDNA encoding a 337-amino acid protein (hKCNK1) with four transmembrane segments and two pore regions containing the signature sequence of K channels. Amino acid identity to TOK1 is only 15% overall but 40% at the pores. Northern analysis indicates high expression of a 1.9-kb message in brain > kidney >> heart. Nephron segment localization, carried out in rabbit by reverse transcription-polymerase chain reaction, reveals that KCNK1 is expressed in cortical thick ascending limb, connecting tubule, and cortical collecting duct. It was not detected in the proximal tubule, medullary thick ascending limb, distal convoluted tubule, and glomerulus. We conclude that KCNK1 is a unique, double-pore, mammalian K channel, distantly related to the yeast channel TOK1, that is expressed in distal tubule and is a candidate to participate in renal K homeostasis. PMID- 9362345 TI - Aquaporin water channels in liver: their significance in bile formation. PMID- 9362346 TI - Extrahepatic biliary obstruction impairs microvascular perfusion and increases leukocyte adhesion in rat liver. AB - To determine if disturbances of the liver microcirculation may be of pathophysiological relevance for liver damage during acute biliary obstruction, we studied the effects of bile duct ligation (BDL) on hepatic microhemodynamics and leukocyte adhesion in rat liver in vivo. Male Wistar rats were subjected to BDL for 3 days and 7 days, respectively. Sham-operated controls underwent laparotomy without BDL. After 3 days, intravital fluorescence microscopy (IVM) and hydrogen gas (H2) clearance were performed to study hepatic microvascular perfusion. Furthermore, leukocyte-endothelial cell interactions were assessed by IVM. Intercellular adhesion molecule 1 (ICAM-1) protein expression was studied by Western blot analysis and tissue immunofluorescence after 3 and 7 days, respectively. Analysis of microvascular perfusion by IVM revealed a marked impairment of sinusoidal perfusion after 3 days. Assessment of H2 clearance confirmed that overall hepatic microvascular perfusion was decreased. In addition, increased leukocyte adhesion in sinusoids and venules could be observed. A concomitant increase of ICAM-1 expression in liver tissue was also noted within the first week after BDL. Our results show that BDL is followed by a marked depression of the hepatic microcirculation and increased leukocyte adhesion in vivo within 3 to 7 days. Together, these findings suggest that deficits in microvascular perfusion and increased neutrophil infiltration may represent a potential source of liver injury during acute biliary obstruction. PMID- 9362347 TI - Human hepatocyte growth factor in bile: an indicator of posthepatectomy liver function in patients with biliary tract carcinoma. AB - We measured the concentration of hepatocyte growth factor (HGF) in bile obtained from patients after hepatectomy. The HGF concentrations in the bile samples were quantified using an enzyme-linked immunosorbent assay (ELISA). By immunoblotting, using a monoclonal antibody raised against the HGF alpha-subunit, the bile HGF, which was purified on a Heparin-Sepharose column, showed a band of the same size as the recombinant HGF alpha-subunit (69 kd). Bile samples were obtained from 24 patients with biliary tract disease before and after hepatectomy by means of biliary drainage. Before surgery, the bile HGF concentrations were minimal (0.8 +/- 0.1 ng/mL); however, after hepatectomy on postoperative day 1 in patients without posthepatectomy liver failure (20 of 24), they increased severalfold (4.1 +/- 0.4 ng/mL, P < .05). The patients with posthepatectomy liver failure (4 of 24) showed no significant increase in bile HGF after hepatectomy (less than 2 ng/mL on postoperative day 1). The volume of the remnant liver correlated positively with the bile HGF concentration. The bile HGF concentration on postoperative day 1 exhibited a significant negative correlation with the maximum concentration of serum total bilirubin after hepatectomy. The concentration of bile HGF was generally higher than that in serum (2.1-fold). Thus, the bile HGF concentration after hepatectomy may be useful for the early assessment of posthepatectomy liver function. PMID- 9362348 TI - Balance between oxidative damage and proliferative potential in an experimental rat model of CCl4-induced cirrhosis: protective role of adenosine administration. AB - Oxidative stress and its consequent lipid peroxidation (LP) exert harmful effects, which have been currently involved in the generation of carbon tetrachloride-induced cirrhosis. However, the recent report that "physiological" LP can be associated with liver regeneration (LR) makes it necessary to discriminate between oxidative stress-induced and LR-associated LP. In rats rendered cirrhotic by continuous CCl4 administration for 4 weeks, moderate cell necrosis and fine fatty infiltration were found. The histological abnormalities were accompanied by increased LP, mainly accounted for by the microsomal and cytosolic fractions and evidence of oxidative stress (decreased hepatic glutathione content and changes in xanthine oxidase and pentose phosphate pathway activities). After 8 weeks, a micronodular cirrhosis developed, but oxidative stress was greatly attenuated, only persisting in the enhanced LP confined to microsomes. Simultaneous administration of adenosine, a reliable hepatoprotector that readily prevents the onset of liver fibrosis, was able to block the oxidative stress induced by the long-term CCl4 treatment but elicited a selective subcellular distribution of increased LP, similar to that found during LR. The adenosine-induced changes in liver LP (mainly in the nuclear fraction) correlated with an increased activity of thymidine kinase. Therefore, data suggest that adenosine-mediated preservation of energy availability and mitochondrial function could participate in preventing the onset of oxidative stress in cirrhotic rats. The latter could induce a successful liver recovery, curtailing the sequence of events leading to fibrogenesis. PMID- 9362349 TI - Human liver transplant perfusate: an abundant source of donor liver-associated leukocytes. AB - In vitro studies designed to examine the mechanisms of immune tolerance after liver transplantation in humans have been hampered by the difficulty in obtaining sufficient numbers of donor liver-associated leukocytes (LALs). We have investigated whether the ex vivo perfusion of donor livers releases a population of LALs that can be readily retrieved from the waste fluid. The mean number of cells recovered after Ficoll-Hypaque density-gradient separation was 2.6 +/- 0.5 x 10(8) cells, with a viability of 94% +/- 2%. The perfusate lymphocytes comprised mainly T cells (39% +/- 2%) with a very low CD4/CD8 ratio and natural killer (NK) cells (56% +/- 6%) with an increase in the proportion of the CD3 CD56+CD16- subset. The activation marker CD69 was present on the majority of the perfusate lymphocytes. These are the phenotypic characteristics that have been previously reported for lymphocytes isolated from hepatic sinusoids. In mixed lymphocyte reactions, the perfusate cells showed a marked increase in the ability to stimulate allogeneic responder cells, resulting in 353% +/- 78% (P = .003) greater incorporation of [3H]thymidine in responder cells when compared with stimulation by donor peripheral blood mononuclear cells. The results show that large numbers of viable donor lymphocytes can be readily isolated from the liver perfusate solution. These cells have the characteristics of liver-associated lymphocytes with a predominance of activated NK and CD8+ T cells. This population can now be used in in vitro assays to elucidate the influence of donor leukocytes on the development of graft acceptance. PMID- 9362350 TI - A randomized trial comparing transjugular intrahepatic portosystemic stent-shunt with variceal band ligation in the prevention of rebleeding from esophageal varices. AB - The aim of this study was to compare transjugular intrahepatic portosystemic stent-shunt (TIPSS) with variceal band ligation (VBL) in the secondary prophylaxis of esophageal variceal hemorrhage in patients with cirrhosis. Fifty eight patients with cirrhosis who presented with the first episode of esophageal variceal hemorrhage were randomized to TIPSS (31) or VBL (27), 24 hours after control of bleeding. Shunt function was assessed after 1 month and then at 6 monthly intervals thereafter. VBL was performed weekly until variceal eradication, and then at 3 months, 6 months, and yearly thereafter. Mean follow up in the TIPSS group was 15.7 (+/-10.2) months; in the VBL group, it was 16.8 (+/-10.9) months. Results for rebleeding and mortality were analyzed on an intention-to-treat basis and using the Kaplan-Meier method. The frequency and the severity of variceal rebleeding was significantly lower in the TIPSS group (9.8%), compared with the VBL group (51.9%) (P < .0006). Although mortality rates were not significantly different, 8 of the patients who rebled in the VBL group required TIPSS therapy for uncontrolled bleeding. No significant differences were found in the frequency of other complications such as encephalopathy and sepsis. Patients in the VBL group required significantly greater time in the intensive care unit during the period of this study (<0.03). The total direct cost of treatment incurred was pound sterling 1,373 ($2,200) per patient, the cost being less in the patients treated with TIPSS compared with VBL. The results of this study show that TIPSS is superior to VBL for the secondary prophylaxis of variceal hemorrhage in patients with cirrhosis. PMID- 9362351 TI - Prevalence, kinetics, and therapeutic modulation of autoantibodies against Sp100 and promyelocytic leukemia protein in a large cohort of patients with primary biliary cirrhosis. AB - Antinuclear antibodies (ANA) staining nuclear dot structures predominantly occur in primary biliary cirrhosis (PBC) patients and recognize the Sp100 and promyelocytic leukemia protein (PML). From retrospective analysis of sera from a clinically well-defined Canadian series of 170 PBC patients included into a 24 month therapeutic trial of ursodeoxycholic acid (UDCA), we report the prevalence of these ANA and their dynamics in the course of the disease. Using an enzyme linked immunosorbent assay (ELISA), anti-Sp100 autoantibodies were shown in 35 (21%) patients. Thirty-three patients (19%) had autoantibodies against PML as determined by indirect immunostaining of cells overexpressing PML. Altogether, anti-nuclear dot autoantibodies were present in 25% of the 170 PBC patients. Their occurrence correlated with an unfavorable disease course, because these patients progressed significantly more frequently from early stages (I/II) to late stages (III/IV) within the 24-month observation period (P < .05). During the course of the disease, the autoantibody levels against the Sp100 full-length protein remained nearly constant in all 35 positive patients. However, 9 patients showed remarkable changes in Sp100 epitope recognition as revealed by ELISA and immunoblotting. When the occurrence of these changes and the treatment of the patients were compared retrospectively, it became evident that 8 of the 9 patients had received UDCA (42% of all Sp100-positive patients treated with UDCA). These findings indicate subtle changes of the Sp100 epitope recognition pattern during the natural course of the disease and its induction or acceleration by UDCA treatment. This implies that UDCA can modulate immunoglobulin (Ig) expression not only quantitatively, but also qualitatively. PMID- 9362352 TI - Evidence of functional and structural cardiac abnormalities in cirrhotic patients with and without ascites. AB - Cirrhosis is associated with cardiovascular abnormalities. Scanty information is available as to whether these include left ventricle diastolic dysfunction and wall thickness increase. To this aim in 27 cirrhotic patients with tense ascites, 17 cirrhotic patients with previous episodes of ascites (not actual), and 11 controls we investigated by echocardiography and echocolor Doppler left ventricle diastolic function (E wave, A wave, E/A ratio, deceleration time of E wave), systolic function (ejection fraction), and wall thickness (left ventricle posterior wall thickness + interventricular septum thickness) along with neurohumoral variables. All measurements (supine position) were repeated after total paracentesis (10.7 +/- 0.6 L of ascites) in ascitic patients. Both in patients with and without ascites E/A ratio was reduced as compared with controls (0.93 +/- 0.07 and 0.97 +/- 0.06 vs. 1.18 +/- 0.08, P < .05) while left ventricle wall thickness was increased (18.6 +/- 0.6 and 20.1 +/- 0.8 vs. 17.2 +/- 0.7, P < .05 and P < .01, respectively), irrespective of the postviral or alcoholic cause of liver disease. In all cirrhotics both right and left atrial and right ventricle diameters were significantly greater. Ejection fraction was slightly but significantly (P < .01) reduced in ascitic patients. Paracentesis induced a reduction of the highly increased basal plasma renin activity, aldosterone, norepinephrine (P < .01), and epinephrine (P < .05) and improved diastolic function (E/A, P < .05). Systolic function was unaffected. Thus, irrespective of ascites and cause, advanced cirrhosis is associated with left ventricle diastolic dysfunction and wall thickness increase. We can speculate that neurohumoral overactivity, known to stimulate cardiac tissue growth, may challenge the heart, promoting fibrosis and exerting a further hindrance to ventricular relaxation in patients with cirrhosis experiencing episodes of ascites. PMID- 9362353 TI - Hepatocellular carcinoma in primary biliary cirrhosis and its impact on outcomes. AB - In this study we have determined the incidence of hepatocellular carcinoma (HCC) development in primary biliary cirrhosis (PBC) and its effects on patient survival. Six hundred and sixty seven patients with liver histology compatible with or diagnostic of PBC were seen over a 20-year period. Two hundred and seventy three patients who had stage III or IV disease on their last biopsy and who had been followed up for at least 1 year following that biopsy (total follow up with advanced disease 2,010 patient years) were identified (243 female, 30 male). Patients who developed HCC were identified and their confounding risk factors were excluded. Mayo risk scores were calculated for each clinic attendance and expected survival for each time point was compared with subsequent actual survival. Sixteen cases of HCC were seen in the patients with stage III or IV disease on last biopsy, providing an overall incidence of 5.9% in this group. Fourteen of these patients had died of HCC related causes, and 2 patients were alive at the census point. The incidence of HCC was significantly higher in males with stage III/IV disease than in females (20% vs. 4.1%, P < .005). Nine of one hundred and eight (8.3%) total female deaths in this group was attributable to HCC compared with 5 of 11 (45.5%, P < .05) male deaths. HCC was not seen in any of the 394 patients with stage I and II PBC followed-up over the same time period. Throughout the disease course of all PBC patients with HCC, the Mayo prognostic model over-predicted survival. Whereas it is a relatively rare complication of cirrhotic PBC in women, HCC is a relatively common cause of death in male PBC patients with cirrhosis. HCC typically develops several years after the onset of cirrhosis, and is poorly predicted by prognostic models. In view of these findings, consideration should be given to careful screening for HCC in male PBC patients with cirrhosis. The risk of HCC development may be an additional reason to consider earlier transplantation in these patients. PMID- 9362354 TI - The prophylactic effect of aprotinin on intraoperative bleeding in liver transplantation: a randomized clinical study. AB - Fibrinolysis has been recognized as an important cause of intraoperative bleeding during orthotopic liver transplantation (OLT). Several investigators have used prophylactic administration of aprotinin in patients to inhibit fibrinolysis and to decrease transfusion requirements, morbidity, and mortality. Nevertheless, the role of aprotinin in this situation is not yet clear. The goal of this study was to determine the effects of prophylactic administration of aprotinin on intraoperative bleeding and blood requirements, and on hemostatic changes during OLT. Eighty consecutive patients were included in a double-blind, prospective study and were randomized in two groups. In group A (n = 39), an initial dose of 2 x 10(6) kallikrein inactivator units (KIU) of aprotinin was administered in the induction of anesthesia followed by infusion of 5 x 10(5) KIU/h until the end of the procedure. The control group (n = 41) received an identical volume of saline solution. The majority of the operations were performed with vena cava preservation (piggy-back technique) without venovenous bypass. During the anhepatic phase, a significant increase in levels of tissue plasminogen activator, thrombin-antithrombin complexes (TAT) and D-dimers (DD) was noted in both groups. A significant increment of TAT was observed in group A during reperfusion. The remaining hemostatic parameters were similar in both groups. Intraoperative requirements of packed red cells, fresh-frozen plasma (FFP), platelets, and cryoprecipitate were similar in the two groups. Our results suggest that prophylactic administration of aprotinin is not useful in reducing bleeding and blood product requirements during OLT. PMID- 9362355 TI - Urinary sodium balance in patients with cirrhosis: relationship to quantitative parameters of liver function. AB - The relationship between the impairment in hepatic and renal function in cirrhosis has not been well established. This study investigated urinary sodium excretion in comparison with quantitative parameters of liver function in 75 patients with various degrees of cirrhosis kept on a constant salt diet of 120 mmol/d for 5 days before the start of the study. The aminopyrine breath test (ABT), indocyanine green (ICG) elimination, galactose elimination capacity (GEC), and hepatic sorbitol elimination (HSE) served as quantitative parameters of liver function. Results for the quantitative tests were compared with those for the Child-Pugh score. Urinary sodium excretion showed a significant nonlinear relationship to ABT (r = .70; P < .0001). Less-significant correlations were observed for ICG (r = .60), the Child-Pugh score (r = -.57), GEC (r = .44), and HSE (r = .34). Because a number of significant correlations were observed between the different liver function tests, multivariate analysis was used to further elucidate the relationship between hepatic function and sodium excretion. Only one independent predictor of urinary sodium excretion could be identified, and that was the ABT (P < .02). More than half of the nonascitic patients showed a urinary sodium excretion of less than 80% of dietary sodium intake, indicating impaired renal sodium handling in preascitic cirrhosis. Based on the 95% confidence interval (CI) for ABT of nonascitic patients with normal (mean ABT 0.56% dose x kg/mmol CO2; 95% CI: 0.44 to 0.69) and reduced urinary sodium excretion (mean ABT 0.26% dose x kg/mmol CO2; 95% CI: 0.18 to 0.35), a threshold level of ABT of about 0.4 (% dose x kg/mmol CO2) for conservation of normal urinary sodium excretion in cirrhosis can be defined. This ABT value reflects an approximate 50% reduction in function compared with the mean of cirrhotic patients with normal liver and kidney function (0.81% dose x kg/mmol CO2). The presence of ascites was also associated with a reduction in ABT to below 0.4 (% dose x kg/mmol CO2), while, for all other parameters, either the cut-off point was close to the lower limit of normal or no cut-off level could be detected. In conclusion, the results of the present study provide further evidence that the impairment in urinary sodium excretion in cirrhosis is related to hepatic function. The data suggest a nonlinear relationship. Because ABT has been shown to reflect functional hepatocellular mass, the occurrence of sodium retention and ascites appears to be related to a threshold of an approximate 50% reduction in functional liver cell mass. PMID- 9362356 TI - Prospective randomized trial of chemoembolization versus intra-arterial injection of 131I-labeled-iodized oil in the treatment of hepatocellular carcinoma. AB - Intra-arterial injection of radioactive Lipiodol has shown promising results in patients with hepatocellular carcinoma (HCC) and portal obstruction. The aim of this prospective, randomized trial was to compare the efficacy and tolerance of 131I-labeled Lipiodol and chemoembolization for the treatment of patients with HCC. From September 1990 to September 1993, 142 patients (135 men, 7 women; age: 65 +/- 6.6 years) were randomly assigned to treatment groups and given either intra-arterial injections of 131I-labeled Lipiodol (60 mCi; 2.2 GBq) (n = 73) or chemoembolization (70 mg cisplatin) (n = 69). Subsequent injections were given at 2, 5, 8, 12, and 18 months. Tumor response was assessed on the basis of tumor size and serum alpha-fetoprotein levels. Patient tolerance was assessed clinically and angiographically. Survival rate was the main end-point. A total of 129 patients (65 in the 131I-labeled Lipiodol group and 64 in the chemoembolization group) were available for analysis; 13 were excluded, mainly because of portal vein thrombosis. The two groups were comparable. Actuarial survival curves were not significantly different between the two groups. Overall survival rates at 6 months, 1, 2, 3, and 4 years were 69%, 38%, 22%, 14%, and 10%, and 66%, 42%, 22%, 3%, and 0% in the 131I-labeled Lipiodol and chemoembolization groups, respectively. Reduction in tumor size was similar for the two groups, with complete response in 1 and 0 patients and partial response in 15 and 16 patients in the 131I-labeled Lipiodol and chemoembolization groups, respectively. Tolerance was significantly better in the 131I-labeled Lipiodol group both clinically (3 severe side effects vs. 29 in the chemoembolization group; P < .001) and angiographically (1 arterial thrombosis vs. 10 in the chemoembolization group; P < .01). In terms of patient survival and tumor response, radioactive 131I-labeled Lipiodol and chemoembolization were equally effective in the treatment of HCC, but tolerance to 131I-labeled Lipiodol was significantly better. PMID- 9362357 TI - Fate of the human liver after hemihepatic portal vein embolization: cell kinetic and morphometric study. AB - The favorable therapeutic effect of preoperative portal vein embolization (PVE) was analyzed by assessing various volumetric, cell kinetic and morphometric parameters and examining histologically the embolized and nonembolized lobes of 15 patients who underwent extended right lobectomy 2 to 3 weeks after PVE. Each lobar volume was calculated from computed tomography (CT) images, hepatocyte proliferation was evaluated by assessing proliferative cell nuclear antigen (PCNA) expression and mitosis, hepatocyte apoptosis was evaluated by the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and the hepatocyte numerical density as well as the sinusoidal volumetric ratio (Vvs) and the mean hepatocyte volume (Cv) were calculated using morphometric methods. PVE induced hepatocyte apoptosis and atrophy of the embolized lobe (from 798 +/- 213 to 708 +/- 222 cm3; P < .05). The increased sinusoidal volume in this lobe (17.7% +/- 4.5% and 21.7% +/- 5.7%, periportal and pericentral area, respectively) may have been attributable to hepatocyte deletion. Cells in the nonembolized lobe entered a highly active phase of proliferation within 2 weeks after PVE. Further evidence of cellular proliferation was provided by the increased nonembolized lobar volume (from 379 +/- 132 to 545 +/- 130 cm3; P < .01) and numerical density of hepatocyte nuclei (Nv) (5.38 +/- 1.26 vs. 3.11 +/- 0.85 x 10(5)/mm3; P < .01, nonembolized vs. embolized lobe, respectively). In conclusion, these results indicate that the favorable effect of PVE is attributable to a net gain of functional hepatocyte mass and/or early induction of hepatocyte proliferation following hepatectomy. PMID- 9362358 TI - Circulating albumin messenger RNA in hepatocellular carcinoma: results of a multicenter prospective study. AB - The presence of circulating tumor cells might be an indicator of hematogenous spread of tumor cells leading to extrahepatic metastasis. Messenger RNA (mRNA) expression of human albumin, as a liver specific cell marker, has been proposed for this purpose in hepatocellular carcinoma. We conducted a multicenter prospective study in 101 patients with biopsy-proven hepatocellular carcinoma followed-up every 3 months for 1 year or until death. At entry into the study, albumin mRNA was detected in the blood by reverse transcription-polymerase chain reaction (RT-PCR). At entry into the study, 45% of the patients had a positive albumin mRNA test, 53% a single tumor, 16% a portal or venous hepatic thrombosis, and 16% had proven metastasis. After 1 year, there was no significant difference in survival of patients with positive or negative albumin mRNA at entry (P = .16, log-rank test). When patients with metastasis at entry were excluded, again survival did not differ between the two groups (P = .20). Independent prognostic factors of survival were radical therapeutic procedures, metastasis, number of tumors, Child-Pugh score, and thrombosis, but not the albumin mRNA test. Taking the presence of metastasis as a reference, the specificity of the test was 56%, its sensitivity 50%, and its negative predictive value 85%. The present study shows that circulating albumin mRNA detected by means of RT-PCR fails to provide significant information in the diagnosis and prognosis of hepatocellular carcinoma. Further studies are needed to determine whether the use of specific tumor markers could have clinical relevance in this setting. PMID- 9362359 TI - Measurement of liver volume and hepatic functional reserve as a guide to decision making in resectional surgery for hepatic tumors. AB - The respective volumes of hepatic tumors and nontumorous parenchyma of 50 patients requiring hepatectomy of more than one segment of Healey for tumor removal were measured using computed tomography (Vol-CT). The volume estimated by Vol-CT was found to correlate with the real weight resected (P < .0001) with a mean absolute error of 64.9 mL. The ratio of the nontumorous parenchymal volume of the resected liver to that of the whole liver (R2) in 15 patients who underwent right or extended right hepatic lobectomy was 43% +/- 15%. Eight of 15 patients with R2s < 60% underwent the procedures without right portal vein embolization (PE). The other seven with R2s exceeding 60% or an indocyanine green retention rate after 15 minutes (ICG15) of 10% to 20% underwent PE: in six of seven, the nontumorous parenchyma of the right hepatic lobe became atrophic and in all seven, the volume of the remaining left hepatic lobe increased with a decrease in the mean R2 from 62% +/- 14% to 55% +/- 8% (P = .0006). In the remaining 35 who underwent other hepatectomy procedures, R2s also remained <60%. Overall, at surgery, in 27 with normal liver function (ICG15 < 10%), R2s exceeded 60% in one, remained at 50% to 60% in five, and <50% in 21, whereas 23 patients except for one with an ICG15 exceeding 10%, had R2s of <50%. The postoperative serum total bilirubin levels in 84% of the patients remained within the normal range and there was no surgery-related mortality. In conclusion, 1) Vol-CT can accurately assess the extent of liver resection, 2) individuals with normal liver function can undergo resection of up to 60% of the nontumorous parenchyma without the need for PE, and 3) PE can be used to reduce the size of the resected tissue and increase the volume of the remnant liver to approximate the target limits in individuals with large tumors or minimally abnormal liver function. PMID- 9362360 TI - The monoethylglycinexylidide test does not correctly evaluate lidocaine metabolism after ischemic liver injury in the rat. AB - Although the monoethylglycinexylidide (MEGX) test defined as a single determination of MEGX plasma concentration after lidocaine injection has been proposed as a liver function test, some discrepancies appeared in assessing the quality of liver donor for transplantation as well as the severity of liver disease. The present study used a severe ischemia-reperfusion liver injury (IRI) in rat to evaluate the various factors able to influence the level of MEGX. The metabolism of lidocaine was studied on microsomes isolated from intact rats and from rats submitted to this liver injury. A significant reduction of the various pathways transforming lidocaine but also MEGX was demonstrated. Lidocaine inhibited the MEGX transformation both in intact and injured liver microsomes. In vivo, plasma MEGX concentrations, determined by high-performance liquid chromatography (HPLC), were lower in IRI than in controls up to 80 minutes after lidocaine injection but not later. By contrast, using the usual commercial fluorescence polarization immunoassay (FPIA), MEGX concentrations were paradoxically higher in IRI than in controls. Moreover, MEGX values obtained using FPIA were threefold higher in controls and ninefold higher in IRI than with HPLC. It was shown that these differences were related to the detection by FPIA of free and mainly of conjugated hydroxy-MEGX that accumulated in plasma from rats submitted to an IRI. These data emphasize the complexity of factors influencing the appearance and disappearance of MEGX because of delayed MEGX formation with liver injury but also to inhibition of its further metabolization. The choice of the sampling time for MEGX determination is critical and has to be optimized in every type of liver injury. Moreover, a specific technique, such as HPLC, will avoid cross-reactivity with other metabolites, which may be particularly abundant when the biliary excretion is impaired. PMID- 9362361 TI - Alterations in guanine nucleotide regulatory protein expression and activity in human hepatocellular carcinoma. AB - Alterations in the expression and activity of guanine nucleotide regulatory proteins (G proteins) have been linked to the growth of several human tumors. We hypothesized that the expression and activity of G proteins are altered in human hepatocellular carcinoma (HCC). The expression of Gi and Gs proteins was determined in six human tumors and six normal controls (adjacent nonneoplastic liver) by Western blotting using specific antisera raised against the alpha subunit of G proteins Gi1, Gi1-2, Gi3, and Gs. Differences in G-protein expression were quantified by densitometry and expressed as percentage change from normal controls. The expression of Gi alpha1 was significantly increased in 80% of tumors (Gi alpha1, 284% +/- 77%; P < .05 percent of normal tissue), whereas Gi alpha1-2 and Gi alpha3 expression was increased in 67% of tumors (Gi alpha1-2, 218% +/- 21%; Gi alpha3, 154% +/- 6%; P < .05 percent of normal tissue). The functional activity of Gi alpha proteins as determined by pertussis toxin-catalyzed adenosine diphosphate (ADP)-ribosylation was also significantly increased in these tumors. In contrast, Gs alpha-protein expression was significantly reduced in all tumors examined (74% +/- 8% of normal tissue, P < .05). The functional activity of Gs alpha, as determined by adenylyl cyclase (AC) activity, was significantly decreased in tumor as compared to normal liver under both basal and agonist stimulated (guanosine triphosphate gamma S and forskolin) conditions. In summary, these data show for the first time a significant alteration in G-protein expression and functional activity in human HCC tissue. These alterations indicate a down-regulation of the AC-linked enzyme effector system in HCC that may be of critical importance to the formation and progression of human hepatocellular carcinoma. PMID- 9362362 TI - Effect of a xanthine analog on human hepatocellular carcinoma cells (Alexander) in culture and in xenografts in SCID mice. AB - Hepatocellular carcinoma (HCC) frequently overexpresses the MDR1 gene and is resistant to drugs transported by the multidrug-resistance efflux pump. A xanthine analog, 1-(11-dodecylamino-10-hydroxyundecyl)-3,7-dimethylxanthine (CT 2584,CTI), is cytotoxic to many tumors in culture and was four times more effective than verapamil in inhibiting Rhodamine 123 secretion in MDR1 overexpressing Chinese hamster ovary cells. However, studies using PRF/PLC/5 (Alexander) cells revealed that CT-2584 is cytotoxic by another mechanism not involving inhibition of MDR1 function. Alexander cells have integrated the hepatitis B surface antigen (HBsAg) gene and quantitatively secrete HBsAg. The parent cell line, Alex 0, has low MDR1 expression and is drug-sensitive, whereas a derived line, Alex 0.5, is drug-resistant and overexpresses MDR1 100 times. Both cell lines were similarly killed within 24 or 48 hours by CT-2584. Freshly isolated rat and human hepatocytes were considerably more resistant to killing by CT-2584. In vivo, CT-2584 significantly reduced tumor growth in SCID mice bearing Alex 0 or 0.5 xenografts as determined by serial measurements of HBsAg. Hepatic parenchyma was normal, whereas apoptosis and cellular loss were observed in xenografts. The xenograft model is useful for testing pharmacological therapy of HCC. PMID- 9362363 TI - Central thyrotropin-releasing hormone stimulates hepatic DNA synthesis in rats. AB - Central neuropeptides play a role as physiological regulators in the autonomic nervous system. One of these neuropeptides, thyrotropin-releasing hormone (TRH), is distributed throughout the central nervous system (CNS) and acts as a neurotransmitter to regulate gastric functions through the vagus nerve. However, the autonomic nervous system is also involved in hepatic regeneration, but the effect of TRH is unknown. Therefore, the CNS's effect of TRH on hepatic DNA synthesis was studied in rats. Hepatic DNA synthesis was assessed by [Methyl 3H]thymidine incorporation 6, 12, 24, 48, and 72 hours after intracisternal injection of the TRH analog, RX 77368 (1, 5, 10, and 100 ng), and by 5-bromo-2' deoxyuridine (BrdU) labeling of the liver section. Hepatic DNA synthesis was stimulated by intracisternal TRH analog (10 ng), with a peak response at 24 hours after peptide injection, and returned to baseline by 72 hours. This stimulatory effect by central TRH analog on hepatic DNA synthesis was dose-related, ranging from 1 ng to 10 ng (dpm/microg DNA at 24 hours [mean +/- SE]: saline, 95 +/- 6; 1 ng, 114 +/- 14; 5 ng, 318 +/- 57; 10 ng, 693 +/- 78; 100 ng, 710 +/- 135). Hepatocytes were randomly labeled by BrdU 24 hours after intracisternal TRH analog (10 ng). Intravenous TRH analog (10 ng) did not influence hepatic DNA synthesis. The stimulatory effect of TRH analog was blocked by hepatic branch vagotomy and atropine, but not by hepatic sympathectomy, 6-hydroxydopamine, insulin antibody, or hypophysectomy. These results indicate that TRH acts in the CNS to stimulate hepatic DNA synthesis through vagal and cholinergic mechanisms, and that TRH may be the chemical messenger involved in brain regulation of hepatic proliferation. PMID- 9362364 TI - Morphological study of vascular dissemination in a metastatic hepatocellular carcinoma model in the monkey. AB - In this report we describe a metastatic monkey hepatocellular carcinoma (HCC) model in which intravascular metastatic development is clearly evident. The tumor bearing livers contained intravenous tumor thrombi at different stages of progression within the small branches of the portal vein. These ranged from mural tumor thrombi lined with CD31-positive endothelial cells to tumor thrombi that had completely occluded the vascular lumen. Intravenous tumor expansion was frequently accompanied by the appearance of CD31-positive microvessels within the tumor thrombi and fibrous perivascular thickening, giving rise to isolated tumor nodules within the portal areas. Intravascular expansion of disseminating HCC was also evident within small branches of the pulmonary arteries in the lungs. These findings indicate that metastases of HCC can become established while still at an intravascular stage, suggesting that the direct interaction between tumor cells and parenchymal cells predicted from experimental rodent metastasis models is not a prerequisite for the metastatic development of these tumors. PMID- 9362365 TI - Quantitation of sinusoid-like vessels in hepatocellular carcinoma: its clinical and prognostic significance. AB - Angiogenesis is crucial for tumor growth and metastasis. Hepatocellular carcinoma (HCC) is a typical hypervascular tumor. However, the relationship between tumor vascularity and the outcome of patients with HCC has not been evaluated. To clarify whether tumor angiogenesis is related to the prognosis of patients, immunohistochemical staining, using anti-von Willebrand factor (vWF) and anti CD34, was applied in resected specimens from 43 cases of HCC. In nonmalignant tissue, staining was confined to vessels in the portal tract and to a few periportal sinusoids with both of the endothelial markers applied. In tumor tissue, however, sinusoid-like vessels reacted intensively with anti-CD34 but not with anti-vWF. The intratumor microvessel density (MVD) highlighted by anti-CD34 was 297 +/- 88 (per 0.74 mm2), which was significantly higher than that highlighted by anti-vWF (4 +/- 7). When only the MVD highlighted by anti-CD34 was analyzed, tumor diameter larger than 2 cm, poor differentiation (Edmondson's II to IV), and portal invasion were significantly related to the subgroup with MVD > or = 290. Overall survival curves of patients with MVD < 290 were better, and these patients were more likely to remain tumor free. Cox hazards model revealed intratumor MVD and Edmondson's grade to be independent prognostic factors for the overall survival of patients. These results demonstrated for the first time that tumor angiogenesis assessed by anti-CD34 was correlated with the outcome of patients with HCC, suggesting a potential role for anti-CD34 in the diagnosis and treatment of HCC. PMID- 9362366 TI - The application of image analysis and neural network technology to the study of large-cell liver-cell dysplasia and hepatocellular carcinoma. AB - Liver cell dysplasia (LCD) is considered a preneoplastic lesion, whose characterization and differentiation from hepatocellular carcinoma (HCC) and from the reactive changes seen in cirrhosis has been controversial. We studied 12 cases of LCD (large cell type) with image analysis techniques (IA) and compared the findings with those of HCC (n = 40), and a spectrum of non-neoplastic hepatic lesions including normal liver and cirrhosis (n = 49). A minimum of 200 Feulgen stained nuclei were measured from each lesion with the CAS 200 image analysis system. The data were collected with the aid of CellSheet software. Thirty-four variables were measured, including geometric, textural, and photometric nuclear features and DNA ploidy. The data were analyzed with multivariate statistics and a backpropagation neural network (NN). Stepwise statistical analysis selected 22 variables that were statistically significant in the three groups with P values <.05. Various NN architectures were developed using these variables. The best NN architecture included a sigmoidal transfer function, 14 input, 16 hidden, and 3 output neurons. It trained to completion after 8,887 runs using 90% of the lesions. This NN yielded a 100% cross-validation rate for unknown cases. These data support the concept of LCD (large cell type) as a lesion that can be objectively distinguished from HCC and non-neoplastic liver. Our study also demonstrates the potential usefulness of IA for the evaluation of difficult histopathological problems. PMID- 9362367 TI - Paracrine interaction between hepatocytes and macrophages after extrathyroidal proteolysis of thyroglobulin. AB - Thyroglobulin (Tg), the precursor of the thyroid hormones triiodothyronine (T3) and thyroxine (T4), is known to derive from thyroid epithelial cells. Part of Tg reaches the circulation as an intact molecule by transcytosis across the epithelial wall of thyroid follicles. Circulating Tg is a potential ligand for the asialoglycoprotein receptor of hepatocytes. In this report we show, however, that clearance of circulating Tg occurred exclusively by endocytosis in liver macrophages, whereas hepatocytes did not participate in this process. The biological significance of this Tg uptake by the macrophages might consist in an increase of thyroid hormones in close proximity to the macrophages, thereby affecting the hepatocyte metabolism. To test this hypothesis, co-cultures of hepatocytes and macrophages were incubated with Tg, which resulted in the release of thyroid hormones and in a significant increase in the activity of lipogenesis and of hepatocellular key enzymes of the hexose monophosphate shunt. This effect of Tg could be mimicked by equivalent amounts of T3 or T4 exclusively in the co cultures. When hepatocytes were incubated with thyroid hormones in the absence of macrophages, no or only little effect was observed, indicating that the interaction of macrophages and hepatocytes was a prerequisite for the stimulation of the hepatocellular metabolism. We conclude that the paracrine effect on HepG2 cells results from the degradation of Tg in J774 cells. Apparently, this process is not confined to the release of thyroid hormones, but it requires the interaction of both cell types, possibly mediated by an additional, as yet unknown stimulus. PMID- 9362368 TI - Protective action of hepatocyte growth factor for acute liver injury caused by D galactosamine in transgenic mice. AB - Hepatocyte growth factor (HGF) has been reported to be a potent mitogen for hepatocytes in vivo and in vitro. Recent reports have shown that HGF has cytoprotective actions in acute liver injury models, but its mechanisms remain to be resolved. In the present study, we investigated whether HGF could work as an anti-hepatitis agent for acute liver injury caused by D-galactosamine (D-GalN) using transgenic (TG) mice expressing HGF in hepatocytes, compared with wild-type (WT) mice of their siblings. After administration of 3 g/kg body weight of D GalN, elevated serum transaminase levels and severe liver damage that were observed in WT mice were significantly improved in TG mice. In TG mice, the percentage of proliferating cell nuclear antigen (PCNA)-positive hepatocytes was high at 0 hours after D-GalN treatment, and increased at 24 hours. The percentage of PCNA-positive cells in WT mice was very low at 0 hours and 24 hours after treatment, but increased at 48 hours. To clarify the mechanisms via which HGF acts, we measured hepatic HGF and prostaglandin E2 (PGE2) contents after D-GalN administration by an enzyme immunoassay. Total hepatic HGF contents, which were composed of murine (endogeneous) and human (derived from transgene) HGF, in TG mice were higher than those in WT mice at 0, 12, and 24 hours after administration of 3 g/kg body weight of D-GalN. Hepatic PGE2 contents in TG mice were also significantly higher than those in WT mice. Hepatic PGE2 contents had a positive correlation with total HGF contents at both 12 hours and 24 hours after the treatment. Moreover, an administration of 0.5 microg of anti-HGF antibody into the portal vein suppressed hepatic PGE2 contents of mice, compared with saline-injected mice in acute liver injury. Anti-PGE2 antibody administration caused more severe liver damage than saline solution. A survival rate of TG mice that were given 6 g/kg body weight of D-GalN-a lethal dose of D-GalN-was improved compared with WT mice. These results provided direct evidences that HGF worked as an anti-hepatitis agent against acute liver injury caused by D-GalN, and that this action might be exerted through accelerated hepatic PGE2 production. PMID- 9362369 TI - Effects of blockade of Kupffer cells by gadolinium chloride on hepatobiliary function in cold ischemia-reperfusion injury of rat liver. AB - The mechanisms of liver injury from cold storage and reperfusion are not completely understood. The aim of the present study was to investigate: 1) whether the inactivation of Kupffer cells (KCs) by gadolinium chloride (GadCl) modulates cold ischemia-reperfusion injury of rat liver; and 2) whether cold storage of rat liver involves injury to biliary epithelial cells (BECs). Hepatobiliary function was assessed using an isolated perfused rat liver model. Compared with control livers, in livers subjected to cold storage at 4 degrees C in Euro-Collins solution (EC) for 18 hours or in University of Wisconsin solution (UW) for 48 hours, portal flow was lower and resistance significantly higher, taurocholate (TC) and bromosulfophthalein (BSP) elimination were markedly impaired, bile flow was reduced, and lactate dehydrogenase (LDH) leakage into the perfusate was increased. Pretreatment of rats with GadCl, a selective KC toxicant, abrogated disturbances of the microcirculation in both models, but it did not influence viability and functional parameters of the liver. Most of the parameters studied in livers stored in UW solution for 18 hours were not significantly different from those found in control livers. As to biliary activity of gamma-glutamyl transferase (GGT), as an index of BEC integrity, it was increased with increasing time of cold storage. The reabsorption of glucose from the bile decreased with longer storage time. The results suggest the following: 1) that cold ischemia-reperfusion injury of rat liver is mediated by KC-dependent (hepatic microcirculation) and -independent (parenchymal cell function) mechanisms; and 2) that cold storage of rat liver induces functional impairment of BECs. PMID- 9362370 TI - Maternal and perinatal outcome in severe pregnancy-related liver disease. AB - Acute fatty liver of pregnancy (AFLP) and the syndrome of hemolysis, elevated liver enzyme levels, and low platelet count (HELLP) are rare but major disorders of the third trimester of pregnancy. Over a 10-year period, 46 women (median age, 30 years; range, 17-41 years) developed hepatic dysfunction severe enough to require transfer to our Liver Failure Unit. Three quarters of the women were nulliparous, and 5 had twin pregnancies; the median gestational age was 35 weeks (range, 24-40 weeks). At admission, 32 patients (70%) were preeclamptic and 21 (46%) were encephalopathic and/or ventilated. Thirty-two patients (70%) had clinical features and laboratory values consistent with AFLP, and 7 (15%) had HELLP syndrome. One patient had preeclamptic liver rupture requiring liver transplantation. In 6 other patients, causes of severe liver dysfunction unrelated to pregnancy were found. Infectious complications occurred in 17 of the patients with AFLP (53%) and in 2 of those with HELLP syndrome (29%). Major intra abdominal bleeding occurred in 12 women (10 with AFLP), 9 of whom required laparotomies for clot evacuation. Four patients with AFLP (12.5%) had a fatal outcome, with a corresponding perinatal mortality rate of 9%. There were no maternal or perinatal deaths associated with HELLP syndrome. In contrast to results of many previous studies, the results of this large series suggest a relatively favorable maternal and perinatal outcome in severe AFLP and HELLP syndrome. Further improvements in outcome are likely to be achieved through the prevention of the bleeding and infectious complications associated with these disorders. PMID- 9362371 TI - Fluorescent bile acid derivatives: relationship between chemical structure and hepatic and intestinal transport in the rat. AB - Studies were performed to characterize hepatic and intestinal transport, as well as biotransformation during transport, of a spectrum of fluorescent bile acids containing a fluorophore attached to the side chain. The following two classes of compounds were studied: 1) aminofluorescein (amF) coupled directly to the carboxylic group of a bile acid which was cholic, ursodeoxycholic, or cholylglycine; and 2) nitrobenzoxadiazolyl (NBD) coupled to the epsilon-amino group of a lysine conjugated bile acid, which was cholic or ursodeoxycholic. Fluorescein, a cholephilic organic anion, was studied as a control. Fluorescent bile acids were synthesized and their structures confirmed by nuclear magnetic resonance and mass spectrometry. Using the biliary fistula rat, hepatic transport, biotransformation, and choleretic activity were defined; intestinal absorption was assessed by jejunal or ileal perfusion studies. All fluorescent bile acids had hepatic transport maxima about one-sixth that reported for cholyltaurine, but derivatives of cholylglycine were transported best. Bile acids underwent little (<5%) biotransformation during hepatocyte transport. Only the amF conjugate of cholylglycine had normal choleretic activity; other compounds were hypocholeretic or cholestatic. In contrast, fluorescein was well transported, was partly glucuronidated, and had normal choleretic activity. NBD tagged, but not amF-tagged, bile acids were actively transported by the intestine (ileum > jejunum), and no fluorescent bile acid had passive intestinal permeability; NBD-tagged bile acids were biotransformed during intestinal transport (jejunum > ileum). We conclude that the structure of the fluorophore as well as that of the bile acid influences transport by the hepatocyte and enterocyte. These fluorescent bile acids differ from fluorescein in being impermeable to cell membranes and undergoing little biotransformation during hepatocyte transport. Of these fluorescent bile acids, cholylglycylamF has hepatocyte transport and choleretic properties most closely resembling those of a natural bile acid. PMID- 9362372 TI - Bile acid-independent bile flow is differently regulated by glucagon and secretin in humans after orthotopic liver transplantation. AB - The present study characterizes recovery of bile secretion after orthotopic liver transplantation (OLT) in humans with special regard to hormonal regulation of bile acid-independent bile flow by glucagon and secretin. Sixty-seven patients with an uncomplicated postoperative course were studied during the first 3 weeks after OLT to determine normalization of bile flow. A group of 7 and 10 patients, respectively, underwent a biliary stimulation test by either glucagon at days 7, 14, and 21 after OLT or by secretin at days 2, 10, and 21 after OLT. Secretin tests were similarly performed in patients with acute severe rejection during the first 10 days after OLT, while glucagon tests were performed in patients with acute allograft rejection occurring 2 weeks after OLT. Furthermore, hormone effects were studied in nontransplanted patients after cholecystectomy with indwelling biliary T tube. After OLT, bile secretory function recovered and stabilized within 14 days after surgery by reconstitution of both bile acid dependent and -independent bile flow. Two weeks after OLT, bile secretion was comparable with nontransplanted patients after cholecystectomy. Glucagon and secretin stimulated bile acid-independent bile flow in transplanted and nontransplanted patients significantly, yet secretin choleresis, unlike glucagon choleresis, had already occurred during the first days after OLT and was unaffected by acute allograft rejection. These results allow the speculation that, in humans, glucagon and secretin exert their choleretic activity by different mechanisms and/or at different anatomical sites in the liver. Assuming that secretin acts at the bile duct cells, its secretory capacity was not altered by the transplantation procedure and during moderate or severe rejection episodes, as opposed to glucagon choleresis, which most likely originates in the hepatocytes and requires an entirely reconstituted canalicular transport system after OLT. PMID- 9362373 TI - Postmenopausal estrogen therapy selectively stimulates hepatic enlargement in women with autosomal dominant polycystic kidney disease. AB - The goal of this study was to determine whether use of postmenopausal estrogen (Premarin, Wyeth-Ayerst, Philadelphia, PA) in women with autosomal dominant polycystic kidney disease (ADPKD) increases liver, hepatic cyst, or kidney volume. We also determined whether clinical symptoms correlated with the volume of either the liver or kidneys. Eight women off estrogen (control, C) and 11 others on estrogen (Premarin, E) were studied basally and after 1 year. The two groups were similar in age, weight, age at menarche, and gravida. Volumes of total liver, hepatic cysts, hepatic parenchyma, and total kidney were measured by a validated computed tomography (CT) technique. Estrogen treatment was associated with a selective increase in total liver volume (E vs. C: delta = 7% +/- 12% vs. 2% +/- 8%, P < .03) and no change in kidney volume (E vs. C: delta = 0% +/- 6% vs. -2% +/- 6%, P = NS). Symptoms were common, regardless of estrogen treatment (abdominal pain 60%, shortness of breath 40%, or both 35%). Patients with symptoms of abdominal pain and shortness of breath had significantly increased hepatic volumes (P < .03) but similar kidney volume compared with patients without symptoms. We conclude that estrogen treatment of postmenopausal ADPKD women is associated with selective liver enlargement and that abdominal symptoms in ADPKD patients may be because of extensive hepatic cystic disease. PMID- 9362374 TI - Mechanisms of intrathymic tolerance induction to isolated rat hepatocyte allografts. AB - Intrathymic injection of alloantigen in young adult rats is capable of mediating long-lived transplantation tolerance. In this study, we use a well-defined model of isolated hepatocyte transplantation to define the mechanisms of intrathymic induced tolerance. The recipient rats are Nagase analbuminemic rats (NAR) that are deficient in albumin, to allow for following transplant acceptance using metabolic and genetic markers. Tolerance to allogeneic hepatocyte transplants could be mediated by intrathymic injection of live allogeneic splenocytes, lethally irradiated splenocytes, or isolated hepatocytes. Intrathymic injection of live allogeneic splenocytes, but not of hepatocytes or irradiated splenocytes, resulted in donor microchimerism in peripheral lymphoid organs, with preferential expansion of CD4-positive T cells in the recipient spleens. Tolerance could be adoptively transferred from tolerant animals to naive recipients, but only from those animals that had been inoculated with intrathymic donor splenocytes. We conclude that donor microchimerism is found after intrathymic inoculation of live splenocytes, but is not required for tolerance induction and that microchimerism is not an absolute requirement for the generation of regulatory cells. PMID- 9362375 TI - The effect of N-methyl-N'-nitro-N-nitrosoguanidine on cultured dog gallbladder epithelial cells. AB - Normal dog gallbladder epithelial cells in long-term culture were used as a model to study the morphologic, genetic, and secretory processes associated with the progression to cancer formation. Dog gallbladder epithelial cells cultured on collagen-coated plates grew into polarized monolayers, could be passaged repeatedly, and showed the typical morphological profile of well-differentiated columnar epithelial cells. After cells were exposed to N-methyl-N'-nitro-N nitrosoguanidine (MNNG) at 10(-5) mol/L for 48 hours, the treated cells grew on plastic and could be cloned. Flow cytometry revealed emergence of an aneuploid cell subpopulation. In organotypic culture, treated cells showed a pseudostratified appearance, with cellular and nuclear pleomorphism. Large and hyperchromatic nuclei were present as well as increased mitotic rate. The proteins of MNNG-treated dog gallbladder epithelial cells showed increased phosphorylation of tyrosine residues. Treated cells showed a decrease in mucin secretion in response to prostaglandin E2, manifesting an altered pattern of mucin secretion. Transforming growth factor-beta failed to inhibit cell proliferation in the MNNG-treated cells compared with the prominent inhibition in normal cells. Together, the data reflected changes representing preliminary steps on the pathway to develop cancer cells. Our results indicate that carcinogenic chemicals can cause measurable chromosomal and cellular modifications to normal biliary epithelial cells in vitro. This model may be useful in understanding the sequential steps in carcinogenesis and affords an opportunity to study chromosomal damage, cytokinetics, changes in molecular genetic markers, and expression, as well as cell biological function during cellular transformation. PMID- 9362376 TI - Cluster mannosides can inhibit mannose receptor-mediated tissue-type plasminogen activator degradation by both rat and human cells. AB - Recently, we developed a series of cluster mannosides that were able to inhibit tissue-type plasminogen activator (t-PA) binding to the isolated mannose receptor. The mannoside with the highest affinity was able to inhibit t-PA clearance by the liver in the rat. To test whether these mannosides would also be efficient inhibitors in humans, we studied the expression of the mannose receptor in the human liver and determined the efficacy of the mannosides to inhibit mannose receptor-mediated t-PA degradation by both rat and human cells. Immunohistochemistry indicates that, like the rat, human liver endothelial cells and human Kupffer cells do express the mannose receptor. The mannosides do inhibit mannose receptor-mediated t-PA binding, association, and degradation by isolated rat liver endothelial cells and t-PA association and degradation by cultured human macrophages at similar concentrations. The cluster mannoside with six mannose residues connected with a backbone of five lysine groups (M6L5) was, like unlabeled t-PA, able to inhibit 125I-t-PA degradation in the nmol/L range, while the mannoside M5L4 inhibited 125I-t-PA degradation in the micromol/L range. The concentrations of mannoside necessary to inhibit 125I-t-PA degradation in vitro were comparable with the concentrations necessary to inhibit mannose receptor-mediated 125I-t-PA clearance in vivo. We conclude that there is no species difference between rat and humans with respect to the distribution of the mannose receptor in the liver and the affinity of the cluster mannosides, establishing the relevance of the inhibition of mannose receptor-mediated t-PA clearance by M6L5 as observed in the rat, for the human situation. PMID- 9362377 TI - The precore sequence of hepatitis B virus is required for nuclear localization of the core protein. AB - The cellular localization of the precore/core and core proteins was studied by immunofluorescence following transfection of 143 thymidine kinase-negative (TK ) and Hep-G2 cells with expression constructs containing wild-type (hepatitis B e antigen [HBeAg]-positive) and precore mutant (HBeAg-negative) sequences. Precore/core constructs with the wild-type phenotype result in strong nuclear staining, while, in contrast, constructs expressing core antigen alone have strong cytoplasmic staining. These differences in the pattern of immunofluorescence staining may be caused by expression of the precore/core protein, some of which may be translocated into the nucleus, following removal of the signal peptide. In vitro translation experiments showed that the main protein products obtained in the presence of microsomal membranes were the precore/core protein and a truncated product representing the same protein without its signal peptide. Core protein expression from the precore mutant constructs was very much reduced, indicating that translational re-initiation was not very efficient. The significance of the precore/core protein being present in the nucleus is not clear, but suggests that it may be important in the replicative cycle of the virus. Finally, HBeAg produced by some of the constructs could not be detected because amino acid substitutions affected antibody-binding epitopes. PMID- 9362378 TI - A pilot study of recombinant interleukin-2 for treatment of chronic hepatitis C. AB - The optimal and safer interleukin-2 (IL-2) dose for treatment of chronic hepatitis C virus (HCV) infection has been studied in 33 HCV-RNA positive patients with chronic hepatitis C. Patients were randomly allocated to receive 5 days per week during 12 weeks IL-2 doses of: 0.9 MIU (n = 10), 1.8 MIU (n = 10), or 3.6 MIU (n = 13). After 12 weeks, responder patients stopped treatment, whereas nonresponders received 12 additional weeks of IL-2 at the next higher dose: 1.8, 3.6, or 5.4 MIU. As a whole, after the first 12 weeks of IL-2 alanine aminotransferase (ALT) levels significantly decreased (P < .001) with respect to the baseline values (140 +/- 63 vs. 70 +/- 30 IU/L). At the end of treatment (24 weeks), the mean ALT level (80 +/- 50 IU/L) continued significantly lower (P < .001) than the baseline one, and 24% of patients normalized ALT levels; according to dosage, ALT normalization was: 0% for 0.9 MIU, 25% for 1.8 MIU, 5% for 3.6 MIU, and 18% for 5.4 MIU. HCV-RNA levels decreased during treatment, but in none of the patients became undetectable. All patients had a local reaction at the injection site with induration, erythema, and swelling, which was dose-related. The dose of 5.4 MIU was poorly tolerated and was reduced to 3.6 MIU in 4 of 11 patients. No changes in hematological parameters were observed. At the end of follow-up (6 months) four of eight responder patients continued with normal ALT. In conclusion, IL-2 treatment for chronic hepatitis C induced a biochemical response in 8 of 33 (24%) patients at the end of therapy while at the end of follow-up, 4 of 33 (8%) patients remained with normal ALT. The dose of 1.8 MIU is well tolerated and seems to be the most efficacious. PMID- 9362379 TI - Hepatitis C and G co-infection: response to interferon therapy and quantitative changes in serum HGV-RNA. AB - Hepatitis G virus (HGV), a positive sense RNA virus, is distantly related to hepatitis C virus (HCV): its genetic organization and identity are consistent with the Flaviviridae family. Coinfection with HGV occurs in 10% to 20% of HCV infected subjects. These similarities raise two theoretical questions. First, could HGV coinfection play any role in the response of HCV to antiviral therapy and second, would this coinfected population have changes in serum HGV-RNA induced by interferon. To address these questions, 98 patients with documented chronic HCV underwent interferon therapy (3 million units three times a week) for 6 months. Response to therapy was categorized using standard biochemical criteria. Changes in HGV-RNA levels were evaluated before, during, and after interferon therapy by a quantitative branched DNA amplification research-based assay. Eleven of 98 (11%) patients with HCV infection had detectable serum HGV RNA. There was no difference between the groups (HGV+ vs. HGV-) when baseline alanine aminotransferase (ALT) values, HCV-RNA levels, HCV genotype, histological severity, or other demographic features were analyzed. Interferon response was similar in both groups and HGV was not associated with outcome following therapy. Antiviral therapy appeared to induce a reduction in HGV-RNA load in five of nine patients coinfected with HCV serially tested. In two patients, the fall in serum HGV-RNA correlated with biochemical response, independent of changes in HCV-RNA. These observations indicate that a larger study of an HGV population is required to more clearly define the relationship between HCV and HGV coinfection and their response to antiviral therapy. PMID- 9362380 TI - Molecular characterization and dynamics of hepatitis C virus replication in human fetal hepatocytes infected in vitro. AB - The molecular features of hepatitis C virus (HCV) replication in human fetal hepatocytes (HFHs) were addressed in this study. Using a competitive reverse transcription polymerase chain reaction (RT-PCR) assay for the quantitation of HCV-RNA molecules, the highest level of viral replication was detected 30 days' postinfection. At this time point, viral particles of 41 to 45 nm in diameter accumulated in the cell cytoplasm. Their density in cell extracts and culture medium was distributed between heavy (1.180-1.360 g/cm3) and light fractions (1.105-1.050 g/cm3) of a sucrose gradient, while, in the serum inoculum, they had a positive fraction at 1.180 g/cm3. In infected HFHs, minus-strand HCV RNA was observed in fractions displaying a sedimentation coefficient of 28 S to 18 S, while plus-strand HCV RNA showed a peak restricted to the 21 S fraction; the HCV RNA of serum inoculum had a sedimentation coefficient of 38 to 40 S, which revealed the presence of HCV RNA of unique positive polarity. The 21 S RNA fraction of cell extracts was resistant to 20 minutes of RNase I digestion, while the same incubation time totally inactivated a comparable amount of HCV RNA purified from the serum inoculum, revealing the presence of completely and/or partially double-stranded HCV-RNA molecules in the infected cells. Detection in HFHs of replicative forms and replicative intermediates suggests that the dynamic profile of HCV replication in these cells is similar to that described in other flaviviruses. PMID- 9362381 TI - Long-term outcome of hepatitis B e antigen-positive patients with compensated cirrhosis treated with interferon alfa. European Concerted Action on Viral Hepatitis (EUROHEP). AB - The aim of this study was to evaluate whether interferon alfa (IFN-alpha) treatment-associated virological and biochemical remission improves survival in a cohort of 90 white patients with compensated cirrhosis caused by hepatitis B (Child A) followed for a mean period of 7 years. Inclusion criteria were biopsy proven cirrhosis, hepatitis B e antigen (HBeAg) positivity, abnormal serum aminotransferase levels, exclusion of hepatitis delta virus, and absence of complications of cirrhosis. Of the 40 IFN-treated patients, 27 (67%) showed sustained HBeAg loss with alanine aminotransferase (ALT) normalization. Of the 50 untreated patients, 30 (60%) cleared HBeAg, but only 21 (42%) normalized ALT after HBeAg loss. Compared with the untreated patients, IFN-treated patients had similar cumulative rates of HBeAg clearance (P = .48), but higher rates of ALT normalization (P = .016) and of HBsAg loss (P = .028). During follow-up, liver related death occurred in 8 treated patients, caused by liver failure in 5 and hepatocellular carcinoma (HCC) in 3; all 8 had continued to be HBeAg-positive with elevated ALT. None of the treated patients undergoing remission developed liver-related complications. At univariate analysis, life expectancy was longer in treated patients showing sustained remission than in those who did not (5-year survival: 100% vs. 81%; P = .048). Fourteen untreated patients died (from liver failure in 10 and HCC in 4); all but 3 had continued to be HBeAg-positive with elevated ALT. Cox's model identified age and ALT normalization as the only significant predictors of survival. In conclusion, in patients with HBeAg positive compensated cirrhosis, virological and biochemical remission following IFN therapy is associated with improved survival. PMID- 9362382 TI - Long-term longitudinal study of intrahepatic hepatitis C virus replication after liver transplantation. AB - Recurrence of hepatitis C after liver transplantation is common and can lead to severe liver diseases. Although immunosuppression and high levels of viremia suggest a direct pathogenicity of hepatitis C virus (HCV), the relations between viral replication and long-term histological course are still unknown. Thirty three patients with a mean histological follow-up of 3.5 years (3 months - 8.6 years) were analyzed. Nineteen patients were infected by genotype 1b. Liver HCV RNA was determined in parallel with the quantitation of an internal control (28S ribosomal RNA) by competitive polymerase chain reaction (PCR). Lobular hepatitis (LH) and chronic active hepatitis (CAH) occurred in 27 and 19 patients, respectively. Levels of liver HCV RNA determined in 84 biopsies were higher in cases of LH than in the other patterns (82 +/- 123 vs. 19 +/- 38; P < .01) and were unrelated to the genotype. Progression from LH to CAH was associated with a highly significant decrease of liver HCV RNA (P = .006), which was not observed in patients with stable histology. Among patients with CAH, those infected by genotype 1b had more severe liver damage and lower levels of liver HCV RNA than others (P = .04). Multivariate analysis showed that high levels of liver HCV RNA at the time of the first posttransplantation biopsy was an independent predictor of CAH (P = .01). After liver transplantation, the progression to CAH together with a decrease of liver HCV RNA suggests that a host's response is involved in the long-term viral pathogenicity. This response may be stronger and liver disease more severe in patients with high levels of replication at the time of LH and in those infected by genotype 1b. PMID- 9362383 TI - Inhibition of hepatocellular carcinoma development in hepatitis B virus transfected mice by low dietary casein. AB - In a comprehensive human ecological study, primary liver cancer has been shown to be highly significantly associated with 1) the prevalence of persistent infection with hepatitis B virus (HBV) and 2) plasma cholesterol concentrations that are, in turn, associated with the consumption of animal based foods. In rat studies, aflatoxin-induced hepatocellular carcinoma is substantially prevented by decreasing the intake of animal based protein (casein), a hypercholesterolemic nutrient. Thus the development of primary liver cancer associated with persistent HBV infection or with aflatoxin exposure may be controlled by reduced intake of animal-based proteins. Transgenic mice transfected with an HBV gene fragment containing the viral transactivator of hepatis B virus, HBx, which induces the formation of hepatocellular carcinoma, were used to examine the ability of dietary casein to modify tumor formation. Reducing the concentration of dietary casein to 6% from the traditional level of 22% markedly inhibited (by 75%) hepatic tumor formation in these transgenic mice. Tumor development also was substantially altered by interchanging dietary casein concentration well after tumor development had begun (at 8 months), increasing by 173% from the expected yield when casein intake was increased and decreasing by 99% when casein was reduced. These findings suggest that the development of liver tumor formation among individuals persistently infected with HBV may be controlled by minimizing or eliminating the intake of animal protein-based foods. PMID- 9362384 TI - Liver and biliary disease research supported by the National Institutes of Health. PMID- 9362385 TI - TIPSS trials: design determines outcome. PMID- 9362386 TI - Genetic hemochromatosis in alpha1-antitrypsin-deficient liver disease. PMID- 9362387 TI - Dose-finding study of interferon alfa-n3 in hepatitis C. PMID- 9362388 TI - Galactosamine-induced fulminant hepatic failure. PMID- 9362389 TI - Mutations in the calcium-sensing receptor and their clinical implications. AB - Specialized cells (i.e., parathyroid chief cells) that sense changes in the extracellular calcium concentration are a key element in mineral ion homeostasis. The Ca2+o-sensing receptor (CaR) originally cloned from bovine parathyroid is also present in multiple nephron segments involved in Ca2+o homeostasis as well as in other sites that are not, such as brain, lung, large and small intestine. The physiological relevance of the CaR has been established by identifying hyper- and hypocalcemic disorders resulting from CaR mutations: familial hypocalciuric hypercalcemia (FHH) and neonatal severe hyperparathyroidism result from inactivating CaR mutations, while an autosomal dominant form ofhypocalcemia is caused by activating mutations. In addition to sensing Ca2+o and Mg2+o abnormally (the latter suggesting the CaR acts as an Mg2+o-sensing receptor), persons with FHH have alterations in their handling of water, supporting a role for the CaR in integrating mineral ion and water metabolism. Drugs that activate the CaR ('calcimimetics') are currently undergoing clinical trials and will permit pharmacological manipulation of the receptor when it functions abnormally (e.g., in primary hyperparathyroidism). PMID- 9362391 TI - Immunohistochemical detection of the melanocortin 1 receptor in human testis, ovary and placenta using specific monoclonal antibody. AB - We describe the immunohistochemical detection of the melanocortin 1 receptor (MC1R) protein in human gonadal tissues using a specific monoclonal antibody. The MC1R was found to be present in Leydig's cells in testis, in lutein cells in the corpus luteum and in the nucleus of the trophoblastic cells of the placenta. Though it has been speculated earlier that MC1R is present in gonadal tissues, this is the first report demonstrating the presence of MC1R protein in these cells. PMID- 9362390 TI - Incidence of dysthyroidism during interferon therapy in chronic hepatitis C. AB - Seventy-nine patients (40 males, 39 females) were enrolled in a prospective study of lymphoblastoid interferon-alpha (IFN), 3-5 MU three times weekly. They were randomly assigned to receive either 12 months of IFN therapy, or to 6 months of observation followed by 6 months of IFN therapy. The thyroid functional and immunological status was checked every other month during and after treatment. Before treatment, antithyroid antibodies were found in 6 patients (7.5%). Two were hypothyroid and were excluded from the study before starting IFN therapy. Seventy-seven patients received IFN therapy. Of these, thyroid abnormalities appeared in 6 (7.5%). Hyperthyroidism was observed in 3 patients. Two recovered within a few months, but 1 developed subsequent hypothyroidism. Hypothyroidism was observed in 2 patients. TSH blood values were persistently abnormal, but thyroid antibody levels remained increased and fluctuating. Thyroid function usually recovered within a few months; but 2 patients required hormonal therapy and 1 was treated with carbimazole. In 1 patient, a small thyroid papillary carcinoma was observed, but no evidence of relationship with the liver disease or with IFN therapy was found. In a patient with chronic hepatitis C, systematic thyroid assessment should be performed before initiating IFN therapy, including clinical examination, and measurement of TSH and anti-thyroperoxidase antibodies (TPO Ab). During treatment, a TSH assay every other month appears to be necessary and sufficient. PMID- 9362392 TI - Pubertal changes in insulin secretion and peripheral insulin sensitivity. AB - Using a simple and standardized method we estimated both insulin secretion and insulin sensitivity in peripheral tissues in relation to Tanner pubertal stages. Early insulin response, mean blood glucose (MBG), mean serum insulin (MSI), glucose uptake rate in peripheral tissues and insulin sensitivity index (SI) in response to the standard oral glucose tolerance test were evaluated in 73 normal girls. Study subjects were divided into 4 groups: group 1 (Tanner stage I, n = 20); group 2 (Tanner stage II, n = 14); group 3 (Tanner stages III and IV, n = 15), and group 4 (Tanner stage V, n = 24). Steroid levels and insulin-like growth factors were determined to characterize clinical pubertal development. MBG was similar in all groups but MSI increased at stage II and retained similar values throughout puberty, with those of group I being statistically lower than in the other groups (p < 0.001). When MSI values were adjusted per kilogram of body weight, a significant increase was observed in group II (p < 0.05). The MSI adjusted values were: group 1, 1.0 +/- 0.4; group 2, 1.4 +/- 0.4; group 3, 1.0 +/ 0.3, and group 4, 1.0 +/- 0.4 mU/l/kg. SI values were similar in groups 1 and 2 and significantly lower than in groups 3 and 4 (p < 0.001). Our results confirm both that insulin secretion is related to age and that an insulin-resistant state occurs during puberty. Thus, the insulin-resistant state coincides with Tanner stage II. In conclusion, this mathematical approach is considered to be a simple and reliable method for analyzing the possible alterations in insulin secretion and action in children and adolescents in whom more sophisticated procedures must be limited in this early period of life for ethical reasons. PMID- 9362393 TI - Hypoxia-induced changes in insulin-like growth factors and their binding proteins in pregnant rats. AB - Pregnancy is associated with important changes in the insulin-like growth factor (IGF)-insulin-like growth factor binding protein (IGFBP) axis, but the importance of these growth factors for fetal growth is not well understood. We have recently established a maternal hypoxia model that results in significant intrauterine growth retardation in the fetus, and characterized the IGF-IGFBP axis in growth retarded fetuses. To determine if maternal IGFs and their binding proteins are similarly regulated by hypoxia, we examined their expression in 6 hypoxic dams (13% oxygen, days 14-21 of gestation) and 6 control dams (21% oxygen). There was no significant difference in the food intake between the groups. The mean body weight of hypoxic dams, however, was 20% less than that of controls. Of all the organs, the lungs were most affected by hypoxia, weighing 17% more in the hypoxic dams than in the control dams; placental weight was reduced by 10% in the hypoxic dams. Liver and brain weights were not changed significantly by hypoxia. The mean concentration ofimmunoreactive IGF-I was 123 +/- 11 ng/ml in the hypoxic dams and 130 +/- 18 ng/ml in the control dams (nonsignificant). Similarly, there was no significant difference in hepatic IGF-I mRNA levels determined by solution hybridization nuclease-protection assay. An increase in IGFBP-1, IGFBP-2 and IGFBP-4 concentrations, however, could be observed by Western ligand blotting of the sera of hypoxic dams, compared to control dams. As assessed by Northern blot analysis, there was a 2.8-fold increase in IGFBP-1 mRNA expression in the livers of hypoxic dams compared to controls. Hepatic IGFBP-4 expression was also slightly increased (1.25-fold) in the hypoxic dams. No difference in hepatic IGFBP-2 or IGFBP-3 mRNA was found. Our results show parallel patterns in fetal and maternal IGF and IGFBP responses to hypoxia. This suggests that hypoxia may inhibit fetal growth by both directly affecting the fetus and via inhibition of placental growth. PMID- 9362394 TI - Long-term outcome of male-limited gonadotropin-independent precocious puberty. AB - Long-term outcome of five new cases of male-limited precocious puberty (MPP) is reported. Three patients had positive family history. One patient was untreated; 2 boys received cyproterone acetate (2.0-3.6 mg/kg/daily) without clinical effects. Two patients were treated with ketoconazole (600 mg/daily); in 1, GnRH analogue therapy (Buserelin, 1,600 microg/day) was added after 6 months of effective ketoconazole treatment for development of central precocious puberty. The other patient did not develop central puberty under ketoconazole treatment and improved his predicted adult height from 172.4 to 181.1 cm. Four patients reached final height [B.A. (therapy cyproterone acetate): age 22.0 years, -2.0 SDS; B.G. (untreated): age 15.5 years, -1.7 SDS; M.M. (therapy cyproterone acetate): age 19.5 years, -1.6 SDS; M.F. (therapy ketoconazole plus GnRH analogue): age 21.3 years, -2.2 SDS]; three had reduced testicular volume (B.A.: 1.6/-1.6 SDS; B.G.: -2.1/-2.1 SDS; M.F.: -2.4/-1.9 SDS); one (M.F.) showed oligospermia. We concluded that in MPP cyproterone acetate treatment did not improve final height; ketoconazole was effective in reducing testosterone secretion, but its real effect on final height cannot be determined; the timing of central puberty may be precocious, suggesting that an adjunctive GnRH analogue treatment may be needed. In some patients, testicular impairment may be present in young adulthood. PMID- 9362395 TI - Where are all the women with heart failure? AB - In recent clinical trials of medical therapy for heart failure, only approximately 20% of patients enrolled were women. The reasons for the low enrollment of women have not been clear. Although the incidence of heart failure is higher in men than in women, the prevalence is equal. When men and women with heart failure and a low left ventricular ejection fraction are compared, the women are more symptomatic and have a similarly poor outcome. Because mortality is worse in men than in women in large populations of patients with heart failure, there may be important pathophysiologic differences. Substantial data suggest that women may have diastolic dysfunction more often than men. This difference would explain differences in mortality and the difficulty in enrolling women in studies of medical therapy for heart failure with underlying systolic dysfunction. PMID- 9362396 TI - Long-term angiographic follow-up of coronary balloon angioplasty in patients with diabetes mellitus: a clue to the explanation of the results of the BARI study. Balloon Angioplasty Revascularization Investigation. AB - OBJECTIVES: We sought to compare the angiographic outcome of diabetic patients (treated with insulin or oral hypoglycemic agents) after successful coronary angioplasty with that in nondiabetic patients. The analysis included the outcome of the dilated (restenosis) and nondilated narrowings (disease progression). BACKGROUND: Recent data have confirmed that diabetes mellitus is an important risk factor for long-term adverse events. These adverse events are more common after balloon angioplasty than after bypass surgery (Bypass Angioplasty Revascularization Investigation [BARI]). METHODS: We examined retrospectively 353 coronary angiograms of 248 patients (55 diabetic, 193 nondiabetic) who were referred for diagnostic angiography >1 month after successful angioplasty (1.4 +/ 0.6 [mean +/- SD] repeat angiograms/patient). Restenosis and disease progression/regression were compared between groups by means of quantitative angiography. RESULTS: Baseline clinical and angiographic characteristics were similar in both groups. There was a nonsignificant trend for a higher restenosis rate of dilated narrowings in diabetic patients. There were no significant changes between diabetic and nondiabetic patients in the rates of progression and regression of narrowings that were not dilated during the initial angioplasty. The main difference was in the rate of appearance of new narrowings: There was a 22% increase in the number of narrowings on the follow-up angiogram in diabetic patients (38 new, 174 preexisting narrowings) compared with 12% (86 new, 734 preexisting narrowings) in nondiabetic patients (p < 0.004). Diabetes mellitus and the performance of angioplasty in the artery had an additive risk for development of new narrowings, which were identified in 15 (16.9%) of 89 arteries with and 16 (13.2%) of 121 without angioplasty in diabetic patients and in 42 (12.7%) of 331 arteries with and 38 (7.3%) of 518 without angioplasty in nondiabetic patients (p = 0.009). CONCLUSIONS: The combination of diabetes mellitus and an artery that was instrumented during balloon angioplasty is additive and increases the risk of formation of new narrowing in that artery. This finding may explain the high adverse event rates observed in diabetic patients in the angioplasty arm of the BARI study, most of whom had angioplasty performed in at least two arteries. PMID- 9362397 TI - Trying to understand BARI. Balloon Angioplasty Revascularization Investigation. PMID- 9362398 TI - Predictive factors of restenosis after coronary stent placement. AB - OBJECTIVES: The objective of this study was to identify clinical, lesional and procedural factors that can predict restenosis after coronary stent placement. BACKGROUND: Coronary stent placement reduces the restenosis rate compared with that after percutaneous transluminal coronary angioplasty (PTCA). However, restenosis remains an unresolved issue, and identification of its predictive factors may allow further insight into the underlying process. METHODS: All patients with successful coronary stent placement were eligible for this study unless they had had a major adverse cardiac event during the 1st 30 days after the procedure. Of the 1,349 eligible patients (1,753 lesions), follow-up angiography at 6 months was performed in 80.4% (1,084 patients, 1,399 lesions). Demographic, clinical, lesional and procedural data were prospectively recorded and analyzed for any predictive power for the occurrence of late restenosis after stenting. Restenosis was evaluated by using three outcomes at follow-up: binary restenosis as a diameter stenosis > or =50%, late lumen loss as lumen diameter reduction and target lesion revascularization (TLR) as any repeat PTCA or coronary artery bypass surgery involving the stented lesion. RESULTS: Multivariate analysis demonstrated that diabetes mellitus, placement of multiple stents and minimal lumen diameter (MLD) immediately after stenting were the strongest predictors of restenosis. Diabetes increased the risk of binary restenosis with an odds ratio (OR) [95% confidence interval] of 1.86 [1.56 to 2.16] and the risk of TLR with an OR of 1.45 [1.11 to 1.80]. Multiple stents increased the risk of binary restenosis with an OR of 1.81 [1.55 to 2.06] and that of TLR with an OR of 1.94 [1.66 to 2.22]. An MLD <3 mm at the end of the procedure augmented the risk of binary restenosis with an OR of 1.81 [1.55 to 2.06] and that of TLR with an OR of 2.05 [1.77 to 2.34]. Classification and regression tree analysis demonstrated that the incidence of restenosis may be as low as 16% for a lesion without any of these risk factors and as high as 59% for a lesion with a combination of these risk factors. CONCLUSIONS: Diabetes, multiple stents and smaller final MLD are strong predictors of restenosis after coronary stent placement. Achieving an optimal result with a minimal number of stents during the procedure may significantly reduce this risk even in patients with adverse clinical characteristics such as diabetes. PMID- 9362399 TI - Intravascular ultrasound findings after successful primary angioplasty for acute myocardial infarction: predictors of abrupt occlusion. AB - OBJECTIVES: This study sought to evaluate the intravascular structure as depicted by intravascular ultrasound after successful primary angioplasty (i.e., without thrombolytic therapy) for acute myocardial infarction and to investigate the related predictors of acute coronary occlusion. BACKGROUND: The usefulness of primary angioplasty for acute myocardial infarction is still limited by early reocclusion. There are few data regarding the intravascular ultrasound findings after primary angioplasty. METHODS: Intravascular ultrasound was performed in 27 patients after successful primary angioplasty. Repeat coronary angiography was performed 15 min later, on the following day and 1 month after angioplasty. RESULTS: Abrupt occlusion occurred in 8 of 27 patients. Angiographic variables in patients with versus those without abrupt occlusion were not significantly different. Intravascular ultrasound disclosed a significantly smaller lumen area ([mean +/- SD] 2.49 +/- 0.72 vs. 5.06 +/- 1.52 mm2, p < 0.001) and a significantly greater percent plaque area (80.5 +/- 9.1% vs. 63.7 +/- 7.8%, p < 0.001) in patients with abrupt occlusion. There was no significant difference in external elastic membrane cross-sectional area. We classified the ultrasound appearance of the intravascular structure as smooth, irregular or filled. Abrupt occlusion occurred in none of 6 patients with a smooth intravascular structure, 24% of 17 patients with an irregular structure and in all 4 with a filled structure (p < 0.05). In the latter group, the lumen was filled with bright speckled or low echogenic material, although angiography revealed excellent coronary dilation in all these arteries. CONCLUSIONS: Intravascular ultrasound revealed a narrow lumen in coronary arteries showing abrupt occlusion after successful primary angioplasty, even though angiography disclosed successful dilation. Arteries with a lumen filled with bright speckled or low echogenic material frequently develop abrupt occlusion. PMID- 9362400 TI - Renal artery stent placement: utility in lesions difficult to treat with balloon angioplasty. AB - OBJECTIVES: We assessed the safety and efficacy of stent placement in patients with poorly controlled hypertension and renal artery stenoses, which are difficult to treat with balloon angioplasty alone. BACKGROUND: Preliminary experience with stent placement suggests improved results over balloon angioplasty alone in patients with atherosclerotic renal artery stenosis. METHODS: Balloon-expandable stents were placed in 100 consecutive patients (133 renal arteries) with hypertension and renal artery stenosis. Sixty-seven of the patients had unilateral renal artery stenosis treated and 33 had bilateral renal artery stenoses treated with stents placed in both renal arteries. RESULTS: Angiographic success, as determined by quantitative angiography, was obtained in 132 (99%) of 133 lesions. Early clinical success was achieved in 76% of the patients. Six months after stent placement, the systolic blood pressure was reduced from 173 +/- 25 to 147 +/- 23 mm Hg (p < 0.001); the diastolic pressure from 88 +/- 17 to 76 +/- 12 mm Hg (p < 0.001); and the mean number of antihypertensive medications per patient from 2.6 +/- 1 to 2.0 +/- 0.9 (p < 0.001). Angiographic follow-up at a mean of 8.7 +/- 5.0 months in 67 patients revealed restenosis (>50% diameter narrowing) in 15 (19%) of 80 stented vessels. CONCLUSIONS: Renal artery stenting is an effective treatment for renovascular hypertension, with a low angiographic restenosis rate. Stent placement appears to be a very attractive therapy in patients with lesions difficult to treat with balloon angioplasty such as renal aorto-ostial lesions and restenotic lesions, as well as after a suboptimal balloon angioplasty result. PMID- 9362401 TI - Accuracy of currently available techniques for prediction of functional recovery after revascularization in patients with left ventricular dysfunction due to chronic coronary artery disease: comparison of pooled data. AB - OBJECTIVES: This study evaluated the relative merits of the most frequently used techniques for predicting improvement in regional contractile function after coronary revascularization in patients with left ventricular dysfunction due to chronic coronary artery disease. BACKGROUND: Several techniques have been proposed for predicting improvement in regional contractile function after revascularization, including thallium-201 (Tl-201) stress-redistribution reinjection, Tl-201 rest-redistribution, fluorine-18 fluorodeoxyglucose with positron emission tomography, technetium-99m sestamibi imaging and low dose dobutamine echocardiography (LDDE). METHODS: A systematic review of all reports on prediction of functional recovery after revascularization in patients with chronic coronary artery disease (published between 1980 and March 1997) revealed 37 with sufficient details for calculating the sensitivity and specificity of each imaging modality. From the pooled data, 95% and 99% confidence intervals were also calculated. RESULTS: Sensitivity for predicting regional functional recovery after revascularization was high for all techniques. The specificity of both Tl-201 protocols was significantly lower (p < 0.05) and LDDE significantly higher (p < 0.01) than that of the other techniques. CONCLUSIONS: Pooled analysis of 37 studies showed that although all techniques accurately identify segments with improved contractile function after revascularization, the Tl-201 protocols may overestimate functional recovery. The evidence available thus far indicates that LDDE appears to have the highest predictive accuracy. PMID- 9362402 TI - Ischemic preconditioning in unstable coronary syndromes: evidence for time dependence. AB - OBJECTIVES: We hypothesized a time-dependent relation between angina occurring spontaneously before percutaneous transluminal coronary angioplasty (PTCA) and the likelihood of an ischemic response during initial balloon occlusion. We further hypothesized that the ability to elicit the "classic" mode of PTCA related preconditioning would vary with the interval from clinical angina to PTCA. BACKGROUND: Antecedent angina represents a potential for myocardial preconditioning in unstable ischemic coronary syndromes. METHODS: We studied 67 patients with Braunwald class III unstable coronary syndromes undergoing PTCA. The interval between the last spontaneous episode of angina preceding PTCA and initial balloon inflation was categorized as follows: 0 to 6 h; 6 to 12 h; 12 to 24 h; and >24 h. RESULTS: Across the various intervals, there was a significant difference (p = 0.004) in the proportion of patients with an absent ischemic response during the first balloon inflation (0 to 6 h, 50%; 6 to 12 h, 35%; 12 to 24 h, 23%; and >24 h, 4%). There was, however, no difference between the first and second inflations in the proportion of patients with a diminished ischemic response until 6 to 12 h (p = 0.017) had elapsed since the last spontaneous episode of angina. Patients whose angina last occurred >24 h before the first inflation showed the greatest inducibility of PTCA-related preconditioning. CONCLUSIONS: Strong evidence exists for the occurrence of ischemic preconditioning in unstable coronary syndromes. Although the protective effect of spontaneous angina appears to wane beyond 6 h, recovery of preconditioning occurs from 6 to 12 h. Thus, preconditioning can be reinduced during PTCA with a marked potentiation of the effect at 24 h. This suggests an underlying time-dependent mechanism with a physiologic "half-life" of 6 to 12 h. PMID- 9362404 TI - Reduced myocardial flow reserve in non-insulin-dependent diabetes mellitus. AB - OBJECTIVES: We analyzed myocardial flow reserve (MFR) in patients with non insulin-dependent (type II) diabetes mellitus (NIDDM) without symptoms and signs of ischemia. BACKGROUND: Diminished MFR in diabetes has been suggested. However, it remains controversial whether MFR is related to glycemic control, mode of therapy or gender in NIDDM. METHODS: Myocardial blood flow (MBF) was measured at baseline and during dipyridamole loading in 25 asymptomatic, normotensive, normocholesterolemic patients with NIDDM and 12 age-matched control subjects by means of positron emission tomography and nitrogen-13 ammonia, after which MFR was calculated. RESULTS: Baseline MBF in patients with NIDDM ([mean +/- SD] 74.0 +/- 24.0 ml/min per 100 g body weight) was comparable to that in control subjects (73.0 +/- 17.0 ml/min per 100 g). However, MBF during dipyridamole loading was significantly lower in patients with NIDDM (184 +/- 99.0 ml/min per 100 g, p < 0.01) than in control subjects (262 +/- 120 ml/min per 100 g), as was MFR (NIDDM: 2.77 +/- 0.85; control subjects: 3.8 +/- 1.0, p < 0.01). A significantly decreased MFR was seen in men (2.35 +/- 0.84) compared with women with NIDDM (3.18 +/- 0.79, p < 0.05); however, no significant differences were found in terms of age, hemoglobin a1c and baseline MBF. MFR was comparable between the diet (2.78 +/- 0.80) and medication therapy groups (2.76 +/- 0.77) and was inversely correlated with average hemoglobin A1c for 5 years (r = -0.55, p < 0.01) and fasting plasma glucose concentration (r = -0.57, p < 0.01) but not age or lipid fractions. CONCLUSIONS: Glycemic control and gender, rather than mode of therapy, is related to MFR in NIDDM. PMID- 9362403 TI - Short-term estrogen administration ameliorates dobutamine-induced myocardial ischemia in postmenopausal women with coronary artery disease. AB - OBJECTIVES: This study was designed to examine whether short-term estrogen administration ameliorates dobutamine-induced myocardial ischemia in postmenopausal women with coronary artery disease (CAD). BACKGROUND: Estrogen replacement therapy in postmenopausal women is associated with a marked reduction in the risk of CAD. Estrogen has been reported to have both short- and long-term effects on the cardiovascular system. However, it remains to be examined whether short-term estrogen administration ameliorates myocardial ischemia caused by increased myocardial oxygen demand in postmenopausal women with CAD. METHODS: Eight postmenopausal women with proved CAD underwent dobutamine stress echocardiography (DSE). DSE was performed three times in a placebo-controlled, double-blind manner: 1) 30 min after intravenous administration of saline solution (placebo) and after 2) a low dose (1.25 mg) and 3) a high dose (10 mg) of conjugated estrogen. The effects of estrogen were compared at the maximal comparable stage of DSE, which was the maximal DSE level that the same patient achieved in all three examinations. RESULTS: Estrogen dose-dependently ameliorated the dobutamine-induced worsening of symptoms (prolonging time to onset of symptoms by 52% [low dose] and 72% [high dose]), electrocardiographic findings (decreasing the magnitude of summed ST segment changes by 36% [low dose] and 76% [high dose]) and left ventricular wall motion (reducing the wall motion score index by 50% [low dose] and 77% [high dose], all p < 0.01 by analysis of variance). There was no significant difference in blood pressure, heart rate or rate-pressure product among the three examinations at the maximal comparable stage of DSE. CONCLUSIONS: Estrogen has short-term anti-ischemic effects on the myocardial ischemia induced by increased myocardial oxygen demand in postmenopausal women with CAD. PMID- 9362405 TI - Comparative prognostic significance of simultaneous versus independent resolution of ST segment depression relative to ST segment elevation during acute myocardial infarction. AB - OBJECTIVES: We sought to determine the prognostic significance of simultaneous versus independent resolution of ST segment depression that occurs concomitant with ST segment elevation during acute myocardial infarction (AMI). BACKGROUND: ST segment depression in leads other than those showing ST segment elevation during AMI is a common phenomenon. Whether this indicates adverse outcomes remains controversial. We hypothesized that the timing of ST segment depression resolution relative to ST segment elevation resolution might differentiate between a high risk group and a low risk group of patients. METHODS: Continuous 12-lead ST segment monitoring was performed after thrombolytic therapy for AMI in 413 patients, 261 of whom met technical criteria for analysis. Blinded analysis of ST segment depression resolution patterns was used to group patients as follows: 1) no ST segment depression at any time (control group); 2) ST segment depression resolving simultaneously with ST segment elevation (simultaneous group); and 3) ST segment depression persisting after ST segment elevation resolution (independent group). These patterns were correlated with the outcomes recurrent angina, reinfarction, heart failure and death-using chi-square analysis and the Fisher exact test for categoric variables and the Wilcoxon rank-sum test for continuous variables. RESULTS: The incidence of recurrent angina, reinfarction and heart failure was similar among the three groups. In-hospital mortality, however, was significantly higher in the independent group (13%) than either the simultaneous group (1%, p < 0.001) or the control group (0%, p = 0.002). CONCLUSIONS: Continuous analysis of ST segment resolution identifies, among patients with AMI with concomitantly occurring ST segment elevation and depression, a subgroup with increased in-hospital mortality. The pathogenic mechanism of increased mortality is not currently known. PMID- 9362406 TI - Incidence and mortality from early stroke associated with acute myocardial infarction in the prethrombolytic and thrombolytic eras. Secondary Prevention Reinfarction Israeli Nifedipine Trial (SPRINT) and Israeli Thrombolytic Survey Groups. AB - OBJECTIVES: This study sought to compare the incidence of early cerebrovascular events and subsequent mortality in two cohorts of consecutive patients with acute myocardial infarction (AMI), admitted to coronary care units (CCUs) in Israel, in the prethrombolytic and thrombolytic eras. BACKGROUND: During the past decade, substantial changes have occurred in the medical treatment of AMI, and important new therapies have been introduced that could all affect stroke risk and type by diverse mechanisms. Yet the overall impact of these new therapeutic modalities on the incidence of stroke complicating AMI is not clear. METHODS: We compared the incidence and mortality rates of cerebrovascular events complicating AMI within CCUs among 5,839 consecutive patients admitted in the period 1981 to 1983 versus 2,012 patients from two prospective nationwide surveys conducted in all CCUs operating in Israel in 1992 and 1994. RESULTS: The demographic and clinical characteristics of patients with AMI in both periods were comparable. Patients admitted in the period 1981 to 1983 did not receive thrombolysis and reperfusion therapy; those admitted in 1992 and 1994 received thrombolysis (45%) and coronary angioplasty or coronary artery bypass graft surgery (14%), and antiplatelet and anticoagulant treatments were more frequently used. The incidence of early cerebrovascular events was 0.74% (43 of 5,839) in 1981 to 1983 versus 0.75% (15 of 2,012) in the 1992 to 1994 cohort. Patients with an AMI who experienced a cerebrovascular event were somewhat older in both groups and had a high rate of previous cerebrovascular events, congestive heart failure and atrial and ventricular arrhythmias during the hospital period. Mortality declined by one third between the two periods. However, the mortality rate of patients with AMI who sustained a cerebrovascular event remained high (> or =40% for 30 days, 60% for 1 year). CONCLUSIONS: The overall incidence of early cerebrovascular events complicating AMI remained similar (0.75%) in the prethrombolytic and thrombolytic eras. Mortality rates of patients with an AMI but no cerebrovascular events decreased substantially over the past decade but not in patients with AMI with a cerebrovascular event. PMID- 9362407 TI - Modulation of lipoprotein(a) atherogenicity by high density lipoprotein cholesterol levels in middle-aged men with symptomatic coronary artery disease and normal to moderately elevated serum cholesterol. Regression Growth Evaluation Statin Study (REGRESS) Study Group. AB - OBJECTIVES: This study sought to examine whether lipoprotein(a) levels predict coronary artery lumen changes in patients with symptomatic coronary artery disease (CAD) and normal to moderate hypercholesterolemia. BACKGROUND: Recent conflicting reports have confirmed or refuted the association of lipoprotein(a) with clinical events or angiographically verified disease progression. METHODS: The association between serum lipoprotein(a) and changes in coronary artery lumen was studied in 704 men entered into the Regression Growth Evaluation Statin Study (REGRESS), a double-blind, placebo-controlled, quantitative angiographic study that assessed the effect of 2 years of pravastatin treatment. The primary end points were changes in average mean segment diameter (MSD) and average minimal obstruction diameter (MOD). Pravastatin- and placebo-treated patients were classified as having progressing, regressing or stable CAD, and median lipoprotein(a) concentrations were compared. Bivariate and multivariate regression analyses were performed in the overall patient group and in high risk subgroups. RESULTS: Pravastatin treatment did not affect serum apolipoprotein(a) levels. Median in-trial (sampled at 24 months) apolipoprotein(a) levels for regressing, stable and progressing CAD were, respectively, 130, 162 and 251 U/liter in placebo-treated patients and 143, 224 and 306 U/liter in pravastatin treated patients. Predictors of MSD and MOD changes were baseline MSD and MOD, in trial apolipoprotein(a), in-trial high density lipoprotein (HDL) cholesterol and baseline use of long-acting nitrates. The multivariate models predicted 14% of MSD changes and 12% of MOD changes; apolipoprotein(a) predicted only 2.6% and 4.8%, respectively. However, in patients with in-trial HDL cholesterol levels <0.7 mmol/liter, apolipoprotein(a) predicted up to 37% of the arteriographic changes. CONCLUSIONS: Serum lipoprotein(a) levels predict coronary artery lumen changes in normal to moderately hypercholesterolemic white men with CAD; its atherogenicity is marked in the presence of concomitant hypoalphalipoproteinemia. PMID- 9362408 TI - Out-of-hospital cardiac arrest in the 1990's: a population-based study in the Maastricht area on incidence, characteristics and survival. AB - OBJECTIVES: We sought to describe the incidence, characteristics and survival of out-of-hospital sudden cardiac arrest (SCA) in the Maastricht area of The Netherlands. BACKGROUND: Incidence and survival rates of out-of-hospital SCA in different communities are often based on the number of victims resuscitated by the emergency medical services. Our population-based study in the Maastricht area allows information on all victims of witnessed and unwitnessed SCA occurring outside the hospital. METHODS: Incidence, patient characteristics and survival rates were determined by prospectively collecting information on all cases of SCA occurring in the age group 20 to 75 years between January 1, 1991 and December 31, 1994. Survival rates were related to the site of the event (at home vs. outside the home) and the presence or absence of a witness and rhythm at the time of the resuscitation attempt in out-of-hospital SCA. RESULTS: Five hundred fifteen patients were included (72% men, 28% women). In 44% of men and 53% of women, SCA was most likely the first manifestation of heart disease. In patients known to have had a previous myocardial infarction (MI), the mean interval between the MI and SCA was 6.5 years, with >50% having a left ventricular ejection fraction >30%. The mean yearly incidence of SCA was 1 in 1,000 inhabitants. Of all deaths in the age groups studied, 18.5% were sudden. Nearly 80% of SCAs occurred at home. In 60% of all cases of SCA a witness was present. Cardiac resuscitation, which was attempted in 51% of all subjects, resulted overall in 32 (6%) of 515 patients being discharged alive from the hospital. Survival rates for witnessed SCA were 8% (16 of 208 subjects) at home and 18% (15 of 85 subjects) outside the home (95% confidence interval 1% to 18.8%). CONCLUSIONS: The majority of victims of SCA cannot be identified before the event. Sudden cardiac arrest usually occurs at home, and the survival of those with a witnessed SCA at home was low compared with that outside the home, indicating the necessity of optimizing out-of-hospital resuscitation, especially in the at-home situation. PMID- 9362409 TI - Thromboembolism in chronic atrial flutter: is the risk underestimated? AB - OBJECTIVES: We sought to evaluate the risk of thromboembolic events in the presence of chronic atrial flutter and to determine the impact of anticoagulation therapy, if any, on this risk. BACKGROUND: Thromboembolic events are thought to be rare after cardioversion of atrial flutter. METHODS: This study was a retrospective analysis of 110 consecutive patients referred to the electrophysiology laboratory for cardioversion of chronic atrial flutter from 1986 to 1996. Atrial flutter was present for at least 6 months. Of the 110 patients reviewed, 100 had adequate information available regarding the effectiveness of anticoagulation (mean age 64 years, range 27 to 86; 75 men, 25 women; mean left ventricular ejection fraction 42%). RESULTS: Thirteen patients (13%) had a thromboembolic event. Of these, seven were attributable to causes other than atrial flutter. In the remaining six patients (6%), thromboembolic events occurred during a rhythm of atrial flutter or after cardioversion to sinus rhythm. Other causes of thromboembolism were excluded. Effective anticoagulation was associated with a decreased risk of thromboembolism (p = 0.026). CONCLUSIONS: Patients with chronic atrial flutter are at an increased risk of thromboembolic events. Effective anticoagulation may decrease this risk. PMID- 9362410 TI - Spectrum of clinicopathologic manifestations of arrhythmogenic right ventricular cardiomyopathy/dysplasia: a multicenter study. AB - OBJECTIVES: The aim of the present investigation was to redefine the clinicopathologic profile of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC), with special reference to disease progression and left ventricular (LV) involvement. BACKGROUND: Long-term follow-up data from clinical studies indicate that ARVC is a progressive heart muscle disease that with time may lead to more diffuse right ventricular (RV) involvement and LV abnormalities and culminate in heart failure. METHODS: Forty-two patients (27 male, 15 female; 9 to 65 years old, mean [+/-SD] age 29.6 +/- 18) from six collaborative medical centers, with a pathologic diagnosis of ARVC at autopsy or heart transplantation, and with the whole heart available, were studied according to a specific clinicomorphologic protocol. RESULTS: Thirty-four patients died suddenly (16 during effort); 4 underwent heart transplantation; 2 died as a result of advanced heart failure; and 2 died of other causes. Sudden death was the first sign of disease in 12 patients; the other 30 had palpitations, with syncope in 11, heart failure in 8 and stroke in 3. Twenty-seven patients experienced ventricular arrhythmias (ventricular tachycardia in 17), and 5 received a pacemaker. Ten patients had isolated RV involvement (group A); the remaining 32 (76%) also had fibrofatty LV involvement that was observed histologically only in 15 (group B) and histologically and macroscopically in 17 (group C). Patients in group C were significantly older than those in groups A and B (39 +/- 15 years vs. 20 +/- 8.8 and 25 +/- 9.7 years, respectively), had significantly longer clinical follow-up (9.3 +/- 7.3 years vs. 1.2 +/- 2.1 and 3.4 +/- 2.2 years, respectively) and developed heart failure significantly more often (47% vs. 0 and 0, respectively). Patients in groups B and C had warning symptoms (80% and 87%, respectively, vs. 30%) and clinical ventricular arrhythmias (73% and 82%, respectively, vs. 20%) significantly more often than patients in group A. Hearts from patients in group C weighed significantly more than those from patients in groups A and B (500 +/- 150 g vs. 328 +/- 40 and 380 +/- 95 g, respectively), whereas hearts from both group B and C patients had severe RV thinning (87% and 71%, respectively, vs. 20%) and inflammatory infiltrates (73% and 88%, respectively, vs. 30%) significantly more often than those from group A patients. CONCLUSIONS: LV involvement was found in 76% of hearts with ARVC, was age dependent and was associated with clinical arrhythmic events, more severe cardiomegaly, inflammatory infiltrates and heart failure. ARVC can no longer be regarded as an isolated disease of the right ventricle. PMID- 9362411 TI - Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. Consensus Conference on Prosthetic Valve Thrombosis. AB - OBJECTIVES: We sought to form a consensus recommendation for management of prosthetic valve thrombosis (PVT) from previous case and uncontrolled reports from a consensus of international specialists. BACKGROUND: PVT and thromboembolism relate to inadequate anticoagulation and valve type and location. PVT is suspected by history (dyspnea) and auscultation (muffled valve sounds or new murmurs) and confirmed by Doppler echocardiography showing a marked valve gradient. METHODS: A consensus conference was held to recommend management of left-sided PVT. RESULTS: Transesophageal Doppler echocardiography is used to visualize abnormal leaflet motion and the size, location and mobility of thrombus. Thrombolysis is used for high risk surgical candidates with left-sided PVT (New York Heart Association functional class III or IV) because cerebral thromboembolism may occur in 12% of patients. Duration of thrombolysis depends on resolution of pressure gradients and valve areas to near normal by Doppler echocardiography performed every few hours. Lysis is stopped after 72 or 24 h if there is no hemodynamic improvement (operation indicated). Heparin infusion with frequent measurement of activated partial thromboplastin time (aPTT) begins when aPTT is more than twice control levels and can be converted to warfarin (international normalized ratio [INR] 2.5 to 3.5) plus aspirin (81 to 100 mg/day). Patients in functional class I or II have lower surgical mortality, and those with large immobile thrombi on the prosthetic valve or left atrium have responded to endogenous lysis with combined subcutaneous heparin every 12 h (aPTT 55 to 80 s) plus warfarin (INR 2.5 to 3.5) for 1 to 6 months. Operation is advised for nonresponders or patients with mobile thrombi. CONCLUSIONS: Thrombolysis, followed by heparin, warfarin and aspirin, is advised for high risk surgical candidates with left-sided PVT. PMID- 9362412 TI - Doppler tissue imaging: a noninvasive technique for evaluation of left ventricular relaxation and estimation of filling pressures. AB - OBJECTIVES: This investigation was designed 1) to assess whether the early diastolic velocity of the mitral annulus (Ea) obtained with Doppler tissue imaging (DTI) behaves as a preload-independent index of left ventricular (LV) relaxation; and 2) to evaluate the relation of the mitral E/Ea ratio to LV filling pressures. BACKGROUND: Recent observations suggest that Ea is an index of LV relaxation that is less influenced by LV filling pressures. METHODS: One hundred twenty-five study subjects were classified into three groups according to mitral E/A ratio, LV ejection fraction (LVEF) and clinical symptoms: 34 asymptomatic subjects with a normal LVEF and an E/A ratio > or =1; 40 with a normal LVEF, an E/A ratio <1 and no heart failure symptoms (impaired relaxation [IR]); and 51 with heart failure symptoms and an E/A ratio >1 (pseudonormal [PN]). Ea was derived from the lateral border of the annulus. A subset of 60 patients had invasive measurement of pulmonary capillary wedge pressure (PCWP) simultaneous with Doppler echocardiographic DTI. RESULTS: Ea was reduced in the IR and PN groups compared with the group of normal subjects: 5.8 +/- 1.5 and 5.2 +/- 1.4 vs. 12 +/- 2.8 cm/s, respectively (p < 0.001). Mean PCWP (20 +/- 8 mm Hg) related weakly to mitral E (r = 0.68) but not to Ea. The E/Ea ratio related well to PCWP (r = 0.87; PCWP = 1.24 [E/Ea] + 1.9), with a difference between Doppler and catheter measurements of 0.1 +/- 3.8 mm Hg. CONCLUSIONS: Ea behaves as a preload-independent index of LV relaxation. Mitral E velocity, corrected for the influence of relaxation (i.e., the E/Ea ratio), relates well to mean PCWP and may be used to estimate LV filling pressures. PMID- 9362413 TI - Echocardiographic assessment of left ventricular remodeling: are left ventricular diameters suitable tools? AB - OBJECTIVES: We sought to analyze the value of echocardiographic left ventricular (LV) diameters in assessing LV remodeling. BACKGROUND: LV diameters are easily measured and commonly used as a substitute for volumetric analysis to evaluate LV remodeling caused by ventricular overload or dysfunction. However, the impact of these measurements on outcome is disputed, suggesting that they may not adequately assess LV remodeling. METHODS: M-mode echocardiographically measured LV dimensions and the derived LV ejection fraction and end-systolic wall stress were compared with LV volumes and the derived LV ejection fraction and wall stress using the biplane Simpson rule. These measurements were made prospectively and simultaneously in 463 patients (289 men, 174 women; mean [+/-SD] age 62 +/- 15 years), including 46 normal subjects, 52 with aortic regurgitation, 253 with mitral regurgitation and 112 with LV dysfunction. RESULTS: The correlation between diameter and volume was good at end-systole (r = 0.91, p < 0.0001) and end-diastole (r = 0.86, p < 0.0001). However, the relation was exponential, and the 95% confidence interval increased with increasing diameter. The calculated LV ejection fraction and wall stress using LV diameter and volume correlated linearly with a limited range of error (r = 0.96, SEE = 5%, p < 0.0001 and r = 0.95, SEE = 20 g/cm2, p < 0.0001, respectively). CONCLUSIONS: For assessing LV remodeling, LV diameters measured by M-mode echocardiography allow acceptable estimation of LV ejection fraction and wall stress and correlate significantly with LV volumes but are hindered by a wide range of error for assessment of LV size, especially for enlarged ventricles, suggesting that measurement of LV volume should be the preferred method of echocardiographically assessing LV remodeling. PMID- 9362415 TI - Conditions with right ventricular pressure and volume overload, and a small left ventricle: "hypoplastic" left ventricle or simply a squashed ventricle? AB - OBJECTIVES: We modeled the utility of preoperative potential left ventricular (LV) volume in predicting postoperative volume in conditions causing LV compression. BACKGROUND: With right ventricular (RV) overload lesions, LV "hypoplasia" may be primarily due to compression by reverse septal bowing. If so, preoperative potential LV volume should correspond 1:1 with postoperative volume. The potential volume for a given endocardial circumference can be calculated from the maximal potential cross-sectional area (where A = circumference(2)/4pi) and LV length. METHODS: We studied echocardiographic variables from 22 patients with RV overload lesions perioperatively. RESULTS: Preoperative LV volume was 15.0 +/- 7.1 ml/m2 (59% of patients had a volume <15 ml/m2); potential volume was 20.0 +/- 9.8 ml/m2. Postoperative volume increased to 28.2 +/- 8.6 ml/m2 (100% of patients had a volume >15 ml/m2). Preoperative potential volume correlated well with, but generally underestimated, postoperative volume (r = 0.75, p < 0.0001). Postoperative increases in both LV circumference and length contributed to this discrepancy. CONCLUSIONS: In RV overload lesions, LV "hypoplasia" is primarily due not to compression; rather it is due to underfilling. Even "hypoplastic" ventricles can achieve an adequate cavity after operation normalizes loading conditions. Both true and potential preoperative volume can predict postoperative volume well. However, potential volume, which is less prone to underestimating ventricular adequacy, may better help to determine suitability for biventricular repair in lesions of RV overload associated with a "hypoplastic" LV. PMID- 9362414 TI - One- to ten-year follow-up results of balloon angioplasty of native coarctation of the aorta in adolescents and adults. AB - OBJECTIVES: We attempted to evaluate the role of balloon angioplasty in the treatment of discrete coarctation of the aorta in adolescents and adults, with special emphasis on long-term results. BACKGROUND: Controversy persists over the use of balloon dilation for the treatment of native coarctation of the aorta. METHODS: Between July 1986 and January 1997, 43 consecutive adolescent and adult patients with discrete coarctation of the aorta underwent balloon angioplasty. One- to 10-year follow-up data of 37 patients, including results of cardiac catheterization and magnetic resonance imaging (MRI), form the basis of this study. RESULTS: No early or late deaths occurred. Balloon angioplasty produced a reduction in the peak to peak coarctation gradient from a mean +/- SD of 69 +/- 24 mm Hg (95% confidence interval [CI] 61 to 76) to 12 +/- 8 mm Hg (95% CI 10 to 14.8) (p < 0.001). Follow-up catheterization 12 months later (37 patients) revealed a residual gradient of 6.7 +/- 6 mm Hg (95% CI 4.6 to 8.9); 3 (7%) of 43 patients had suboptimal results with development of recoarctation, defined as peak gradient >20 mm Hg, with successful repeat angioplasty. A small aneurysm developed at the site of dilation in 3 (7%) of the 43 patients. MRI follow-up data 1 to 10.8 years (mean 5.2 +/- 2.7) after angioplasty (37 patients) revealed no new aneurysm or appreciable change in the size of the preexisting aneurysm in the three patients. The blood pressure had normalized without medication in 27 (73%) of 37 patients at follow-up examination. CONCLUSIONS: Balloon angioplasty is safe and effective and should be considered a viable alternative to operation for treatment of discrete coarctation of the aorta in adolescents and adults. PMID- 9362416 TI - Anti-tumor necrosis factor-alpha improves myocardial recovery after ischemia and reperfusion. AB - OBJECTIVES: This study sought to assess the importance of locally released or paracrine myocardial tumor necrosis factor-alpha (TNF-alpha) in the evolution of postischemic myocardial dysfunction and to use immunohistochemical studies to localize TNF-alpha within the myocardium. BACKGROUND: TNF-alpha is implicated as a systemic mediator in the development of myocardial ischemia-reperfusion injury by promoting leukocyte myocardial infiltration, and it has been shown to originate from noncardiac peripheral mononuclear cells. We have recently documented in a blood-free environment the release of TNF-alpha from the ischemic reperfused myocardium. METHODS: Isolated rat hearts undergoing 1 h of global cardioplegia-induced ischemia and 30 min of reperfusion were investigated with use of the modified Langendorff model. Hearts were randomly divided into three subgroups: group A, control group; and groups B and C, isolated hearts receiving cardioplegic solution containing monoclonal hamster antimurine TNF-alpha antibodies (group B) or hamster IgG (group C). RESULTS: Significant amounts of TNF-alpha were detected in group A and group C effluent on 1 min of reperfusion (752 +/- 212 and 958 +/- 409 pmol/ml, respectively). However, in group B, TNF alpha was below detectable levels. In this group, postischemic left ventricular peak systolic pressures, first derivative of the rise in left ventricular pressure (dP/dtmax), pressure-time integral, coronary flow and O2 consumption improved (analysis of variance [ANOVA] p < 0.0001 for all variables) compared with values in groups A and C; creatine kinase levels decreased (p < 0.005); and myocardial structure was preserved. Immunohistochemical staining localized TNF alpha to cardiac myocytes and to endothelial cells. CONCLUSIONS: Anti-TNF-alpha neutralizes local TNF-alpha release from cardiac myocytes after ischemia and improves myocardial recovery during reperfusion, indicating that postischemic paracrine TNF-alpha release plays an active role in myocardial dysfunction. PMID- 9362417 TI - Hemodynamic determinants of Doppler pulmonary venous flow velocity components: new insights from studies in lightly sedated normal dogs. AB - OBJECTIVES: We sought to define the hemodynamic determinants of pulmonary venous (PV) flow velocities to assess how these are affected by respiration, heart rate and loading conditions. BACKGROUND: Pulmonary venous flow velocity (PVFV) recorded with pulsed wave Doppler technique is currently used in the noninvasive evaluation of left ventricular (LV) diastolic function and filling pressures. Although previous studies in both animals and humans have shown that PV flow is pulsatile, the hemodynamic determinants of the individual components of this flow remain controversial. Understanding the physiologic mechanisms should help to better define the clinical utility of these Doppler techniques. METHODS: PV flow velocities obtained with transesophageal pulsed wave Doppler imaging were recorded together with PV, left atrial (LA) and LV pressures in 10 sedated, spontaneously breathing normal dogs. PVFV and hemodynamic data were analyzed during apnea, inspiration and expiration, at atrial paced heart rates of 60, 80, 100 and 120 beats/min and mean LA pressures of 6, 12, 18 and 24 mm Hg. RESULTS: The data showed that 1) PV pressure varied depending on recording site, resembling pulmonary artery pressure closer to the pulmonary capillary bed and LA pressure closer to the venoatrial junction; 2) PVFV qualitatively followed changes in the PV-LA pressure gradient; 3) four PVFV components exist under normal conditions-three of which follow phasic changes in LA pressure and one of which (the late systolic component) is more influenced by RV stroke volume and the compliance of the pulmonary veins and left atrium; 4) normal respiration and changes in heart rate significantly alter PVFV variables--in particular, reverse flow velocity at atrial contraction; and 5) increasing LA pressure results in larger PV A wave and PV early systolic flow velocities, as well as an earlier peak in PV late systolic flow velocity and a more prominent velocity minimum before PV diastolic flow. CONCLUSIONS: Using transesophageal pulsed wave Doppler technique, four PVFV components are identifiable and determined by PV-LA hemodynamic pressure gradients. These gradients appear to be influenced by a combination of physiologic events that include RV stroke volume, the compliance of the pulmonary vasculature and left atrium and phasic changes in LA pressure. PV flow velocity components are significantly influenced by heart rate, respiration and LA pressure. These findings have implications for the interpretation of LV diastolic function and filling pressures by current Doppler echocardiographic techniques but require further clinical investigation. PMID- 9362418 TI - Further observations to elucidate the role of interventricular dispersion of repolarization and early afterdepolarizations in the genesis of acquired torsade de pointes arrhythmias: a comparison between almokalant and d-sotalol using the dog as its own control. AB - OBJECTIVES: We sought to further elucidate the role of early afterdepolarizations (EADs) and interventricular dispersion of repolarization (deltaAPD) in the genesis of acquired torsade de pointes (TdP) arrhythmias. BACKGROUND: Administration of class III agents can be associated with TdP. We developed a dog model in which TdP can be reproducibly induced by pacing after d-sotalol. This model shows reproducible results over weeks. METHODS: In 14 anesthetized dogs with chronic complete atrioventricular block, two separate experiments were performed in which d-sotalol (2 mg/kg body weight) or almokalant (0.12 mg/kg) was administered. Monophasic action potentials were simultaneously recorded from the endocardium of the right and left ventricle to register EADs and to measure the action potential duration (APD). DeltaAPD was defined as the APD of the left ventricle minus that of the right ventricle. RESULTS: Baseline conditions were identical in the serially performed experiments. The cycle length and QT time increased by 16% and 26% after d-sotalol and by 15% and 31% after almokalant, respectively. After both drugs the action potential of the left ventricle prolonged more than that of the right ventricle, thereby increasing deltaAPD (almokalant [mean +/- SD]: 110 +/- 60 ms; d-sotalol: 80 +/- 45 ms, p < 0.05). The incidence of EADs (18 of 22 vs. 11 of 24, p < 0.05) and single ectopic beats (EBs) (1.5 +/- 2 vs. 24 +/- 32, p < 0.01) was more frequently observed after almokalant than after d-sotalol. Moreover, multiple EBs only occurred after almokalant. These beats interfered with the basic rhythm, leading to dynamic changes in left ventricular APD and to additional increases in deltaAPD. Spontaneous TdP was observed in 9 of 14 dogs after almokalant and could be increased to 12 of 14 with programmed electrical stimulation. After d-sotalol, TdP could only be induced by programmed electrical stimulation (5 of 14, p < 0.05). CONCLUSIONS: In the same dog, almokalant induced more delay in repolarization, more EADs, multiple EBs and more ventricular inhomogeneity in APD than d-sotalol. These changes were related to a higher incidence of TdP and thereby confirm a strong association of the occurrence of EADs, multiple EBs and deltaAPD in the genesis of TdP. These findings also show the possible value of our model for evaluating the proarrhythmic potential of different drugs. PMID- 9362419 TI - General mechanisms of metastasis. AB - In the present article, the steps involved in the process of tumor metastasis are discussed. Several events are required for malignant cells to leave the primary tumor and proliferate at a distant site: vessel formation (angiogenesis), cell attachment, invasion (matrix degradation, cell motility), and cell proliferation. Molecular mechanisms underlying each of these steps are described. Based on blocking these processes, new anti-metastasis therapies are being developed. PMID- 9362420 TI - Bone turnover and biochemical markers in malignancy. AB - There are three principal disturbances in bone remodelling that occur in neoplasia affecting the skeleton. The first is an increase in bone turnover that in solid tumors may be confined to sites of metastases or be a generalized phenomenon, most likely related to the secretion of parathyroid hormone-related protein. In the bone remodelling sequence, bone resorption precedes formation, so that increases in turnover result in substantial skeletal deficits more marked at cancellous than cortical bone sites. The second abnormality in bone remodelling is an imbalance between the amount resorbed and that formed at each remodelling site. This is a conspicuous feature of myelomatosis with moderate grades of plasma cell infiltration. The third phenomenon is the process of uncoupling. In osteolytic disease this is associated with the creation of erosion cavities that are never subsequently repaired. Progressive waves of bone resorption result in the destruction of skeletal elements and focal osteolysis. Osteosclerotic metastases formed by uncoupled bone formation represent the deposition of new bone either on quiescent bone surfaces or arising from stromal condensations within the marrow cavity. In solid tumors biopsy evidence suggests that uncoupled bone resorption and formation occur within the same metastases and that the radiographic expression (osteosclerosis, osteolysis) depends on the predominant component. The understanding that abnormalities of skeletal metabolism are mediated by authentic bone cells raises the possibility that skeletal specific markers of bone turnover might be utilized for the diagnosis of metastases, to assess the skeletal prognosis, or to monitor treatment. A variety of skeletal markers have been assessed. The pyridinium crosslinks currently provide the markers of greatest predictive value. Although they have high specificity, their sensitivity is low (< 30%). This indicates that many individuals with skeletal metastases would be missed. In contrast, skeletal markers have proven invaluable in the assessment of the natural history of the disease and response to intervention. They have been particularly useful in assessing the pharmacodynamics of bisphosphonate treatment. However, their day-to-day precision is sufficiently low that they are of limited value in the monitoring of individuals. PMID- 9362421 TI - Mechanisms of bone metastasis. AB - Solid cancers metastasize to bone by a multistep process that involves interactions between tumor cells and normal host cells. Some tumors, most notably breast and prostate carcinomas, grow avidly in bone because the bone microenvironment provides a favorable soil. In the case of breast carcinoma, the final step in bone metastasis (namely bone destruction) is mediated by osteoclasts that are stimulated by local production of the tumor peptide parathyroid hormone-related peptide (PTH-rP), whereas prostate carcinomas stimulate osteoblasts to make new bone. Production of PTH-rP by breast carcinoma cells in bone is enhanced by growth factors produced as a consequence of normal bone remodeling, particularly activated transforming growth factor-beta (TGF beta). Thus, a vicious cycle exists in bone between production by the tumor cells of mediators such as PTH-rP and subsequent production by bone of growth factors such as TGF-beta, which enhance PTH-rP production. The metastatic process can be interrupted either by neutralization of PTH-rP or by rendering the tumor cells unresponsive to TGF-beta, both of which can be accomplished experimentally. The osteoclast is another available site for therapeutic intervention in the bone metastatic process. Osteoclasts can be inhibited by drugs such as the new generation bisphosphonates; as a consequence of this inhibition, there is a marked reduction in the skeletal events associated with metastatic cancer to bone, such as pain, fracture, and hypercalcemia. However and possibly even more importantly, there is also a reduction of tumor burden in bone. In experimental situations, this has clearly been shown to affect not only morbidity but also survival. The precise mechanism by which bisphosphonates inhibit osteoclasts is still unclear and may represent a combination of inhibition of osteoclast formation as well as increased apoptosis in mature osteoclasts. However, studies with potent bisphosphonates such as ibandronate, pamidronate, and risedronate have clearly documented that reduction of bone turnover and osteoclast activity leads to beneficial effects not only on skeletal complications associated with metastatic cancer, but also on tumor burden in bone. PMID- 9362422 TI - Mechanisms of bone lesions in multiple myeloma and lymphoma. AB - BACKGROUND: Bone lesions and hypercalcemia occur rarely in patients with hematologic malignancies, except those patients with multiple myeloma and adult T cell leukemia/lymphoma (ATL) associated with the human T-cell leukemia/lymphoma virus-1 (HTLV-1) virus. The primary mechanism for bone destruction in patients with myeloma and lymphoma is increased osteoclastic bone resorption. In patients with multiple myeloma, new bone formation is also inhibited. Mediators including lymphotoxin, interleukin-1beta, parathyroid hormone related protein (PTHrP), and interleukin-6, produced by the myeloma cells or by marrow stromal cells in response to myeloma cells, have been implicated as osteoclast-activating factors (OAF) in multiple myeloma. However, most studies to identify OAF produced by myeloma cells have been inconclusive. METHODS: To try to identify the OAF produced by myeloma cells, we developed an in vivo model of human myeloma bone disease using the ARH-77 myeloma cell line transplanted into severe combined immunodeficiency mice. RESULTS: We found that a novel cytokine(s) may be responsible for bone destruction. Interleukin-1 and PTHrP mediate bone destruction in patients with ATL. These factors can be detected in media conditioned by ATL cells or by lymphocytes infected with HTLV-1. Furthermore, serum PTHrP levels are increased in ATL patients. In patients with Hodgkin's disease or other types of non-Hodgkin's lymphoma, 1,25-(OH)2D3 or PTHrP is produced by the lymphoma cells and mediates bone destruction. Chemotherapy or resection of the lymphoma decreases 1,25-(OH)2D3 levels and hypercalcemia in these patients. CONCLUSION: Thus, OAF produced locally by the tumor or the marrow microenvironment play an important role in the bone destruction seen in patients with hematologic malignancies. PMID- 9362423 TI - Parathyroid hormone-related protein and hypercalcemia. AB - The discovery of parathyroid hormone-related protein (PTH-rP) arose from interest in the mechanisms by which certain cancers cause hypercalcemia without necessarily metastasizing to bone. The humoral hypercalcemia of malignancy (HHM) had for a long time been ascribed to inappropriate production of parathyroid hormone (PTH) by cancers. The amino-terminal portions of PTH-rP and PTH have essentially identical actions through a common receptor for PTH/PTH-rP: to elevate plasma calcium by promoting bone resorption and decreasing calcium excretion. Assays for plasma PTH-rP fail to detect protein convincingly in normal plasma, but measurable levels have been found in up to 100% of patients with HHM, in 75% of patients with breast carcinoma metastatic to bone, and in some hypercalcemic patients with miscellaneous cancers. Whereas PTH-rP clearly functions as a hormone in those cancers in which it is produced in excess, in normal circumstances it is produced locally in many tissues in which it is a paracrine effector. There appears to be little doubt that PTH-rP is the major mediator of hypercalcemia in patients with HHM, although it is possible that other factors (e.g., bone resorbing cytokines) also could contribute in some patients. In the case of breast carcinoma, another possible role arises for PTH rP. The high incidence of PTH-rP production by primary breast carcinomas, elevated plasma levels in 60% of those with hypercalcemia and lytic metastases, and higher incidence of PTH-rP production in skeletal versus those with nonskeletal metastases have led to the hypothesis that PTH-rP might contribute to breast carcinoma growth in bone. Experimental evidence currently is available to support this hypothesis. The discovery of PTH-rP has contributed greatly to current understanding of the skeletal complications of cancer. PMID- 9362424 TI - Parathyroid hormone-related protein and bone metastases. AB - Parathyroid hormone-related protein (PTH-rP) was purified and cloned 10 years ago as a factor responsible for the hypercalcemia associated with malignancy. Clinical evidence supports another important role for PTH-rP in malignancy as a mediator of the bone destruction associated with osteolytic metastasis. Patients with PTH-rP positive breast carcinoma are more likely to develop bone metastasis. In addition, breast carcinoma metastatic to bone expresses PTH-rP in >90% of cases, compared with only 17% of metastasis to nonbone sites. These observations suggest that PTH-rP expression by breast carcinoma cells may provide a selective growth advantage in bone due to its ability to stimulate osteoclastic bone resorption. Furthermore, growth factors such as transforming growth factor-beta (TGF-beta), which are abundant in bone matrix, are released and activated by osteoclastic bone resorption and may enhance PTH-rP expression and tumor cell growth. To investigate the role of PTH-rP in the pathophysiology of breast carcinoma metastasis to bone, the human breast carcinoma cell line MDA-MB-231 was studied in a murine model of human breast carcinoma metastasis to bone. A series of experiments were performed in which 1) PTH-rP secretion was altered, 2) the effects of PTH-rP were neutralized, or 3) the responsiveness to TGF-beta was abolished in MDA-MB-231 cells. Cultured MDA-MB-231 cells secreted low amounts of PTH-rP that increased fivefold in response to TGF-beta. Tumor cells inoculated into the left cardiac ventricle of nude mice caused osteolytic metastasis similar to that observed in humans with breast carcinoma. When PTH-rP was overexpressed in the tumor cells, bone metastases were increased. MDA-MB-231 cells transfected with the cDNA for human preproPTH-rP secreted a tenfold greater amount of PTH-rP and caused significantly greater bone metastases when inoculated into the left cardiac ventricle of female nude mice compared with parental cells. In contrast, when the biologic effects of PTH-rP were neutralized or its production was suppressed, such metastases were decreased. Treatment of mice with a neutralizing monoclonal antibody to human PTH-rP resulted in a decrease in the development and progression of bone metastasis due to the parental MDA-MB-231 cells. Similar results were observed when mice were treated with dexamethasone, a potent glucocorticoid that suppresses production of PTH-rP by the MDA-MB-231 cells in vitro. The role of bone-derived TGF-beta in the development and progression of bone metastasis was studied by transfecting MDA-MB-231 cells with a cDNA encoding a TGF-beta type II receptor lacking a cytoplasmic domain, which acts as a dominant negative to block the cellular response to TGF-beta. Stable clones expressing this mutant receptor (MDA/TbetaRIIdeltacyt) did not increase PTH-rP secretion in response to TGF-beta stimulation compared with controls of untransfected MDA-MB-231 or those transfected with the empty vector. Mice inoculated into the left cardiac ventricle with MDA/TbetaRIIdeltacyt had fewer and smaller bone metastases as assessed radiographically and histomorphometrically compared with controls. Taken together, these data suggest that PTH-rP expression by breast carcinoma cells enhance the development and progression of breast carcinoma metastasis to bone. Furthermore, TGF-beta responsiveness of breast carcinoma cells may be important for the expression of PTH-rP in bone and the development of osteolytic bone metastasis in vivo. These interactions define a critical feedback loop between breast carcinoma cells and the bone microenvironment that may be responsible for the alacrity with which breast carcinoma grows in bone. PMID- 9362425 TI - Mechanisms of the development of osteoblastic metastases. AB - Although several neoplasms may produce osteoblastic metastases, carcinoma of the prostate is by far the most common. Biochemical and histologic studies indicate that osteolysis also is a manifestation of prostate carcinoma. Furthermore, factors such as parathyroid hormone-related peptide, which mediate osteolysis in other cancers, also appear to be operative in the bone breakdown induced by prostate carcinoma. However, the most unique skeletal effect of this tumor is its consistent capacity to stimulate osteoblasts to deposit new bone. Several bone growth factors have been detected in prostatic tissue and may contribute to this process. These include transforming growth factor-beta, fibroblast growth factor, and bone morphogenetic proteins. The author isolated an amino-terminal fragment (ATF) of the protease urokinase (uPA) from the conditioned medium of the prostate carcinoma cell line PC-3 and demonstrated that this fragment has mitogenic activity for osteoblastic cells. The activity appears to reside in an epidermal growth factor-like growth factor domain (GFD) within the ATF. Subsequently, the author cloned the rat uPA receptor (uPAR). uPAR is known to bind the ATF and can permit the uPA molecule to exhibit focal proteolysis. It was shown that the ATF also can induce c-myc, c-jun, and c-fos in osteoblastic cells. This effect of ATF can be mimicked by the GFD and suggests that this signalling pathway in osteoblasts is via the uPAR. Consequently, the uPA molecule may contribute to growth factor effects in osteoblasts via the NH2-terminal fragment and to tumor invasiveness via its COOH-terminal proteolytic domain. This scenario is supported by results from studies with uPA-overexpressing prostate carcinoma cells in rats. Additional studies will be required to further define the mechanisms of interaction of prostate carcinoma and other cancers with bone but each site of molecular interaction may provide a therapeutic window for curtailing the effects of these tumors on the skeleton. PMID- 9362426 TI - Skeletal complications of malignancy. AB - The skeleton is the most common organ to be affected by metastatic cancer, and tumors arising from the breast, prostate, thyroid, lung, and kidney possess a special propensity to spread to bone. Breast carcinoma, the most prevalent malignancy, causes the greatest morbidity. Of great clinical importance is the observation that metastatic bone disease may remain confined to the skeleton. In these patients, the decline in quality of life and eventual death is due almost entirely to skeletal complications and their subsequent treatment. Bone pain is the most common complication of metastatic bone disease, resulting from structural damage, periosteal irritation, and nerve entrapment. Recent evidence suggests that pain caused by bone metastasis may also be related to the rate of bone resorption. Hypercalcemia occurs in 5-10% of all patients with advanced cancer but is most common in patients with breast carcinoma, multiple myeloma, and squamous carcinomas of the lung and other primary sites. Pathologic fractures are a relatively late complication of bone involvement. The clinical courses of breast and prostate carcinoma are relatively long, with a median survival of 2-3 years. For patients with breast carcinoma, good prognostic factors for survival after the development of bone metastases are good histologic grade, positive estrogen receptor status, bone disease at initial presentation, a long disease free interval, and increasing age. In addition, patients with disease that remains confined to the skeleton have a better prognosis than those with subsequent visceral involvement. For patients with prostate carcinoma, adverse prognostic features include poor performance status, involvement of the appendicular skeleton and visceral involvement, whereas for patients with multiple myeloma, the levels of serum beta2-microglobulin and lactate dehydrogenase and the immunologic phenotype are the most important factors. These prognostic factors may be useful in planning the rational use of bisphosphonates in the treatment of advanced cancer. PMID- 9362427 TI - Radiologic diagnosis of bone metastases. AB - Metastatic cancer often involves the skeleton. Tumor most often reaches the bones by hematogenous spread; however, direct extension from the primary tumor or from another site of metastasis, as well as lymphatic dissemination, may occur. Clinical features depend on the affected sites and the extent of disease. The radioisotope bone scan has been the preferred imaging screening modality. Magnetic resonance imaging is probably more sensitive in the detection of axial lesions, but additional development is needed before it can replace the isotope scan in evaluation of the long bones. For patients presenting with metastatic disease, the appearance of the lesions may help to guide the search for a primary. Some helpful patterns include lytic and sclerotic lesions, "expanded" lesions, "pseudosarcomatous" lesions, acral lesions, and soft tissue ossification. Evaluation of response to therapy is problematic. Progressive sclerosis of a lytic focus generally indicates a positive response. Pitfalls in the evaluation of response include the "flare" phenomenon, which has been observed on radioisotope scans early in the course of therapy. PMID- 9362428 TI - Mechanisms and management of bone pain. PMID- 9362429 TI - Orthopedic surgical management of skeletal complications of malignancy. AB - Coincident with improved overall cancer palliation during the past 2 decades has been an increasing incidence of clinically apparent bone metastases, and from these metastases subsequent pathologic fractures of the long bones, spine, and pelvis. Current techniques for surgical management of these fractures are extremely effective in alleviating pain and allowing patients to resume an ambulatory status, often without the need of external support. This, in turn, has significantly improved the quality of the remaining months or years of these individuals' lives. In fact, the long term survival of patients after their first long bone pathologic fracture from malignancy has more than tripled for the most common cancers (breast carcinoma, prostate carcinoma, lymphomas, and myelomas) during the past 25 years. Surgical techniques for stabilizing pathologic or impending fractures must be individualized for the area of involvement, the particular qualities of the bone involved, and the potential for involvement of adjacent soft tissue structures. Long bone fractures most commonly occur in the femur and humerus and are typically internally fixed by intramedullary devices that control impaction, distraction, and torquing stresses by the use of proximal and distal interlocking fixation. Such fixation must be able to withstand weight bearing stresses on lower extremity long bones. Upper extremity pathologic fractures are often subjected to distractive forces inherent in lifting and pulling, but they are also subjected to heavy compressive forces, particularly in patients who require crutches or other devices to assist them in walking. Fixation of upper or lower extremity long bone fractures ordinarily may be accomplished with minimal blood loss or morbidity. In contrast, fractures or impending fractures involving the acetabulum necessitate extensive joint reconstruction, with inherent increased potential for morbidity and complications. For this reason, the anticipated prognosis for survival and mobility should be greater preoperatively for patients with acetabular fractures than for patients with fractures of either upper or lower extremity long bones. Most spinal metastases can be managed conservatively. Those requiring surgical intervention present with progressive neurologic compromise, which requires decompression, or spinal instability, which requires stabilization. Constructs for internal stabilization of the spine must not be adversely affected by local postoperative irradiation. Ninety-six percent of patients experience good or excellent relief of pain after internal fixation of pathologic malignant long bone fractures. Eighty-four percent of patients with acetabular fractures experience good or excellent relief of pain after joint reconstruction. Eighty two percent of patients with neurologic compromise secondary to vertebral malignancy improve at least one functional grade after decompression and stabilization, and 88% experience good or excellent relief of spinal pain with restoration of walking ability. Thirty-two percent survived for more than 2 years after spinal decompression and stabilization. Patients with pathologic fractures from metastatic carcinoma of the breast had a mean survival of 24.6 months after surgical management of their fractures. There was a similarly encouraging improvement in the survival statistics for patients with other primary tumor types. Most malignant pathologic fractures of the pelvis, long bones, or spine are amenable to effective stabilization by the techniques described in this article. These techniques allow resumption of weight-bearing ambulation in all but a few patients, good or excellent relief of pain in the vast majority, and an enhanced anticipation of survival and improvement in quality of life. PMID- 9362430 TI - Radiation for bone metastases: conventional techniques and the role of systemic radiopharmaceuticals. AB - Pain management often is difficult in patients with bone metastases. Metastatic disease represents >40% of oncologic practice, and >70% of patients with metastatic disease have uncontrolled cancer-related pain. Significant morbidity caused by pathologic fracture and spinal cord compression can result from untreated bone metastases. Representing both a manifestation of systemic disease as well as causing localized symptoms, bone metastases require a multidisciplinary therapeutic approach. Radiation therapy provides both localized and systemic treatment options in addition to chemohormonal therapies and surgery. External beam irradiation provides palliation in >70% of patients through tumor regression of a localized lesion. Systemic radiopharmaceuticals treat multifocal disease either alone or as an adjuvant to external beam irradiation. Efficient and comprehensive management of bone metastases is imperative because of the associated symptoms, prior therapies, complex underlying medical problems, and clinical presentations that often require emergent interventions. Intensification of pain may be observed with hormonal therapy and systemic radiopharmaceuticals. Symptomatic relief from antineoplastic therapies generally requires 4-12 weeks and may be related to reossification. Symptoms, occurring due to the disease and/or while awaiting response to therapy, must be aggressively managed. Persistent or recurrent pain after therapy may be due to bony instability or fracture before reossification occurs. An Interdisciplinary Bone Metastases Clinic, with representatives from Diagnostic Radiology, Medical Oncology, Nuclear Medicine, Orthopedic Surgery, Pain and Symptom Management, Physical Medicine and Rehabilitation, and Radiation Oncology, was developed that allows coordinated evaluation, treatment, and symptom management of these complex clinical presentations. PMID- 9362431 TI - Issues concerning the role of chemotherapy and hormonal therapy of bone metastases from breast carcinoma. AB - A significant percentage (50-70%) of patients with metastatic breast carcinoma (MBC) will have disease involving the bony skeleton. Clonal selection mediated by parathyroid hormone-related protein and other factors may explain the high incidence of osseous metastases in MBC. The presence of specific growth factors and cytokines in the microenvironment of bone may contribute to the successful establishment and growth of metastatic lesions and also might determine response or resistance of these lesions to chemotherapy or hormonal therapy. Osteolytic bone lesions in MBC frequently give rise to serious clinical problems including bone pain, pathologic fracture, hypercalcemia, and neurologic complications. MBC often is treated with systemic chemotherapy or hormonal therapy. The purpose of this article was to review the recent published literature describing the impact of systemic chemotherapy and hormonal therapy of MBC on the response of bone lesions and their clinical course and complications. Evaluating the response of bone lesions can be problematic and may be complicated by the phenomenon of "tumor flare" that may be observed with either chemotherapy or hormonal therapy. Use of the International Union Against Cancer criteria for the response of bone lesions is recommended. Several studies report objective responses (20-60%) of lytic bone metastases to standard combination chemotherapy regimens such as cyclophosphamide, methotrexate, and 5-fluorouracil and cyclophosphamide, doxorubicin, and 5-fluorouracil, mitoxantrone and 5-FU, newer combinations, and single agents including paclitaxel and docitaxel but responses to vinorelbine may be less frequent. Complete responses of bone lesions to chemotherapy are rare but partial responses and disease stabilization can lead to long term patient benefit. A series from the M. D. Anderson Cancer Center of patients with bone metastases treated with 5-FU, doxorubicin, and cyclophosphamide chemotherapy reported a median duration of response of 14 months. In a recent multicenter study of 195 patients with lytic lesions from MBC treated with chemotherapy, the objective response rate (complete response + partial response) in bone was 18% and 65% of the patients developed at least 1 morbid skeletal event with a median onset of 7.0 months from the start of chemotherapy. Hormone-dependent breast carcinoma has a proclivity to metastasize to bone. In earlier studies comparing aminoglutethimide or medroxyprogesterone acetate with tamoxifen, a higher response rate of bone metastases was observed for the first two agents. However, in more recent studies comparing newer aromatase inhibitors, such as anastrozole, fadrozole, and letrozole, with megestrol acetate, there were no significant differences in rates of response in bone. Patients with MBC with bony lesions respond to both chemotherapy and hormonal therapy and can have a prolonged survival. Therefore such patients are in a more favorable position to benefit from adjunctive supportive therapy such as bisphosphonates intended to reduce skeletal morbidity. PMID- 9362432 TI - Overview of bisphosphonates. PMID- 9362433 TI - Bisphosphonates in multiple myeloma. AB - The major clinical manifestations of multiple myeloma are related to enhanced bone destruction resulting in osteolytic lesions, osteoporosis, and pathologic fractures in most patients as well as hypercalcemia and spinal cord compression in many individuals. These patients frequently require radiation therapy or surgery. In an attempt to reduce these complications, bisphosphonates have been evaluated in several large randomized trials in patients also receiving chemotherapy. Oral etidronate given daily showed no clinical benefit, whereas the use of oral clodronate daily did reduce the development of new osteolytic lesions but did not significantly affect bone pain or rates of pathologic fractures. A large, randomized, double-blind study was conducted in which Stage III multiple myeloma patients received either pamidronate (90 mg) or placebo as a 4-hour infusion every 4 weeks for 21 cycles in addition to antimyeloma chemotherapy. The proportion of patients with at least one skeletal complication was significantly reduced in the pamidronate group compared with the placebo group. Although survival was not different between the pamidronate and placebo groups overall, patients in whom first-line chemotherapy had failed when they entered the trial lived longer with pamidronate treatment than those receiving placebo. Patients who received pamidronate had significant decreases in bone pain, had less analgesic drug use, and had better Eastern Cooperative Oncology Group performance status than patients receiving placebo. Pamidronate was safe and well tolerated during the trial. PMID- 9362435 TI - Bisphosphonates in prostate carcinoma. AB - The majority of the patients with advanced prostate carcinoma have painful skeletal metastases, which are responsible for significant skeletal morbidity and disability. Most of these metastases are osteosclerotic, but it has been shown that the abnormal osteoblastic bone formation within metastases is preceded by osteoclastic activation, which appears to be associated with bone pain. This provides the rationale for using bisphosphonates, which are powerful and selective inhibitors of osteoclastic bone resorption. Several bisphosphonates have been shown to be clinically useful for the treatment of several conditions characterized by abnormal osteoclastic bone resorption, including Paget's disease, primary hyperparathyroidism, myelomatosis, and skeletal metastases. Its efficacy in relieving pain in patients with skeletal metastases due to prostate carcinoma has been confirmed in a few studies. The bisphosphonate clodronate was extensively investigated in the study unit. When infused intravenously i.v. (300 mg/day) relief of bone pain become appreciable within 3 days, sometimes preceded by a transient pain flare. These clinical results are very consistent and the residual pain usually is of extraosseous origin. Thus, with regard to pain of strictly bone origin, unresponsive patients are quite rare. Oral administration also is effective, but due to its limited intestinal absorption the effective dose is on the order of 1600-3200 mg/day. These doses usually are well tolerated, but they may be a problem for severely ill patients. Furthermore, the efficacy of treatment becomes apparent only after a few days. Thus, oral clodronate usually is adopted as a continuation of an i.v. course. The duration of the i.v. therapy should be individualized, but usually the more prolonged the treatment the longer the duration of the effect. For practical reasons, clodronate is infused daily for 5 days (Monday-Friday) and the treatment course is repeated at the time of any significant recurrence. The oral continuation prevents or delays the recurrence of bone pain in most patients, but in some patients this therapy has to be integrated occasionally with i.v. infusion. The duration of the effect for the same bioavailable dose is somewhat related to the degree of malignancy of the primary tumor. In an uncontrolled study, the author also evaluated the effectiveness of alendronate given either i.v. or orally. A single infusion of 5 mg alendronate i.v. produces roughly the symptomatic effect of 5 i.v. infusions of 300 mg clodronate. Alendronate, 40 mg orally/day, was effective in reducing bone pain in 11 of 12 patients with bone metastases due to prostate carcinoma but who were not confined to bed. In some patients with prostate carcinoma and a diffuse metastatic invasion of the skeleton, there is indirect biochemical and histologic evidence of osteomalacia. This can be aggravated by bisphosphonate administration because of the transient striking prevalence of osteoblastic activity over bone resorption, which also occasionally causes the appearance of symptomatic hypocalcemia. Therefore, the use of large oral supplements of calcium is recommended, particularly at the start of therapy. It is conceivable that these calcium supplements also may be able to improve the final clinical outcome of the bisphosphonate therapy. In conclusion, administration of large doses of bisphosphonates is one of the most cost-effective palliation treatments for patients with prostate carcinoma with bone metastases, both as first-line therapy and in the long term. With appropriate doses, a large proportion of patients can be maintained free of bone pain until death. Studies of the ability of lower doses to prevent skeletal morbidity in patients without metastases or with asymptomatic bone lesions are warranted. PMID- 9362434 TI - Bisphosphonates and breast carcinoma. AB - The skeleton is a common site of breast carcinoma metastasis; 75% of patients with breast carcinoma demonstrate bone metastases at autopsy. The lytic destruction of bone in these patients is due to excessive osteoclastic activity. By reducing osteoclastic activity, bisphosphonates inhibit bone resorption. Initial studies of breast carcinoma patients were performed with clodronate, a first-generation bisphosphonate. Studies with small cohorts suggested reduction of pain, analgesic requirement, and development of hypercalcemia. A larger randomized, double-blind, placebo-controlled trial of oral clodronate 1600 mg/day demonstrated a significant reduction of the combined rate of all morbid skeletal events (significant reduction of the incidence of vertebral fractures, rate of vertebral deformity, and hypercalcemic episodes). Trends were observed that favored clodronate for the treatment of nonvertebral fractures and radiotherapy for relief of bone pain. There was no survival difference between the clodronate and placebo groups (Paterson et al., J Clin Oncol 1993;11:59-65). Pamidronate is a second-generation aminobisphosphonate that is a much more potent inhibitor of osteoclastic activity. Phase II studies again suggested an improvement in many of the skeletal complications of breast carcinoma. Two large Phase III studies have recently been completed. Women with Stage IV breast carcinoma who were receiving cytotoxic chemotherapy (380 patients) or endocrine therapy (371 patients) and had at least 1 lytic bone lesion were given either pamidronate 90 mg as a 2-hour infusion monthly for 2 years or a placebo infusion. After the two studies were pooled, 367 patients treated with pamidronate and 384 patients given placebo were available for analysis. The median time to first complication (pathologic fracture, vertebral collapse, spinal cord compression, or treatment of bone with radiation or surgery) was 12.7 months for the pamidronate patients and 7.0 months for placebo patients (P = 0.001). The time to first fracture was 25.2 months for pamidronate patients and 12.8 months for placebo patients (P = 0.003). The proportion of patients with fracture was 40% for pamidronate vs. 52% for placebo (P = 0.002); the proportion with radiation administered to bone was 29% for pamidronate vs. 43% for placebo (P = 0.001); and the proportion with any skeletal event was 51% for pamidronate vs. 64% for placebo (P = 0.001). The skeletal morbidity rate (the number of complications per year) at 24 months was 2.4 for the pamidronate group and 3.7 for placebo (P = 0.001). Pain and analgesic use was decreased among the pamidronate patients. There was no difference in survival between the groups. Not all patients responded to the same dose of bisphosphonate. Recent data suggests that patients who have a normalization of their urinary excretion of N-telopeptide have a reduced risk of progression of disease in bone and fracture. In summary, the addition of pamidronate to standard chemotherapy or endocrine therapy produces a sustained reduction in skeletal complications in breast carcinoma patients with osteolytic bone metastases. PMID- 9362436 TI - Gallium nitrate for the treatment of bone metastases. AB - Gallium nitrate was originally developed as an antineoplastic agent; however, further studies have revealed that this drug has extremely potent effects on turnover of bone, and that low doses can be used to reduce bone resorption. Like the bisphosphonates, gallium nitrate has been studied in both malignant and in nonmalignant conditions. The results of randomized double blind studies have suggested that this drug has superior clinical efficacy relative to etidronate, calcitonin, and pamidronate for the acute control of cancer-related hypercalcemia. In patients with Paget's disease, low doses of gallium nitrate reduce biochemical parameters of accelerated bone turnover, including urinary excretion of calcium, hydroxyproline, and urinary collagen cross-linked N telopeptides. Preliminary studies showed similar effects in patients with bone involvement from a wide variety of tumor types. Based on this high degree of clinical potency revealed in clinical studies, two randomized Phase III studies have been initiated in patients with bone metastases from breast carcinoma and bone involvement due to multiple myeloma. Both studies employ cyclic therapy with low dose gallium nitrate (i.e., 40 mg administered as a subcutaneous injection once daily for 2 weeks, followed by 2 weeks off treatment, recycled monthly). The endpoints of both studies are to document reductions in time to "morbid skeletal events," such as palliative skeletal radiotherapy, stabilizing orthopedic surgery, or pathologic fractures, as well as decreases in pain and analgesic requirements and improvements in mobility and other aspects of quality of life. These trials should provide definitive evidence of whether this agent is safe and effective as a treatment for bone metastases. PMID- 9362437 TI - High dose pamidronate: clinical and biochemical effects in metastatic bone disease. AB - Eighty-six patients with heavily pretreated progressive bone metastases (52 with breast carcinoma, 17 with prostate carcinoma, and 17 others) were included in 2 studies designed to assess the clinical and biochemical effects of a single 120 mg, 2-hour infusion of pamidronate. No other systemic anticancer treatment or radiotherapy were administered. Pamidronate had a significant beneficial effect, with a reduction in a symptom score measuring pain, World Health Organization performance status, and analgesic consumption and improvement in quality of life when compared with a placebo infusion. Symptomatic improvement corresponded with changes in the rate of bone resorption as indicated by the concentrations of pyridinoline crosslinks in the urine. In patients with the highest rates of bone resorption (N-terminal peptide-bound portion of the collagen crosslink or crosslaps excretion > or = twice that of normal) clinical response or normalization of the rate of bone resorption were rarely observed, with all clinical responses occuring in those patients with bone resorption rates of < twice that of normal. Intriguingly, symptomatic response also correlated with a modest (> 10%) fall in tumor marker levels, suggesting a possible effect of bisphosphonates on tumor activity. PMID- 9362438 TI - Clodronate. AB - Clodronate is a second-generation bisphosphonate of intermediate potency between etidronate and aminobisphosphonates. It is an effective inhibitor of bone resorption, but unlike etidronate does not impair the mineralization of bone. Unlike pamidronate, it can be given both intravenously and orally. There is wide experience in the use of clodronate in the management of patients of hypercalcemia. The most widely used therapeutic regimen is 300 mg intravenously repeated for 5 days or a single infusion of 1500 mg. Efficacy is nearly complete in patients with myelomatosis, less complete in solid tumors with hypercalcemia but without skeletal metastases, and intermediate in patients with solid tumors in the presence of skeletal metastases. Variations in effect appear to be due to differences in renal tubular reabsorption of calcium between the three disorders. Placebo-controlled studies examining the effects of clodronate on bone pain in the absence of hypercalcemia have shown significant decreases in the severity of bone pain. These findings, coupled with the knowledge that suppression of bone resorption persists for the duration of treatment, has led to the long term use of oral doses of clodronate to decrease the incidence of complications of osteolytic bone disease. The long term control of bone resorption with oral clodronate has been demonstrated by double blind histologic studies. The ultimate arbiter of the value of clodronate is whether it decreases the skeletal morbidity associated with osteolysis. Double blind prospective controlled studies suggest that the incidence of bone pain, fracture, and hypercalcemia can be decreased significantly in patients with breast carcinoma. In addition, the use of long term clodronate in patients with myelomatosis significantly decreases the progression of osteolytic bone lesions, the risk of fractures, and the incidence of hypercalcemia. These studies have raised the possibility that bone disease might be prevented in individuals at high risk. Double blind prospective studies in women with recurrent breast carcinoma but no evidence of skeletal metastases showed a small effect of clodronate in decreasing the proportion of women developing metastatic disease. However, there was a large and significant decrease in the number of skeletal metastases associated with a decrease in skeletal morbidity. These observations suggest that clodronate may modify the natural history of the expression of skeletal disease, and thereby significantly improve the quality of life of affected patients. PMID- 9362439 TI - Ibandronate in oncology. PMID- 9362440 TI - Clinical research update: zoledronate. AB - The prolonged administration of bisphosphonates can reduce the frequency of morbid skeletal events in patients with metastatic breast carcinoma or multiple myeloma. The development of more potent bisphosphonates will simplify current therapeutic schemes and could improve the therapeutic effectiveness of bisphosphonate therapy. Zoledronate (CGP-42446) is the most potent of the clinically tested compounds. It is a cyclic third-generation bisphosphonate that is 100-850 times more active than pamidronate in several in vivo and in vitro pharmacological test systems. The first therapeutic trial with zoledronate has been performed in patients with tumor-induced hypercalcemia (corrected calcium [Ca] > 2.75 mmol/L after rehydration). In a Phase I multicenter trial, it was shown that a single infusion was already effective at dose levels of 0.02 and 0.04 mg of zoledronate/kg bodyweight, thus 1.2 and 2.4 mg total dose for an average 60-kg individual. Five of 5 patients became normocalcemic after a dose of 0.02 mg/kg, and 14 of 15 (93%) after a dose of 0.04 mg/kg. The median time to normalization of serum Ca was 2 days and the median duration of action was 33 days, suggesting that zoledronate has a faster onset and a longer duration of action than other clinically tested bisphosphonates. Zoledronate was well tolerated; the only side effect was an increase in body temperature in 30% of the cases, which was probably not drug-related in many patients. A Phase I trial also has been initiated in patients with lytic bone metastases. Zoledronate was given as monthly short infusions (5-30 minutes) at doses between 0.1-8.0 mg. There was an analgesic effect and even at low doses (2 mg and above), the effects on the biochemical markers of bone resorption appeared to be greater than after 90-mg pamidronate infusions. These initial human data suggest that zoledronate can be administered as convenient short intravenous infusions and lead to a more marked and a more prolonged inhibition of bone resorption than is currently possible with available compounds. Future trials will have to determine whether prolonged treatment with this extremely potent bisphosphonate also can have a greater effect on the morbidity of bone metastases. PMID- 9362441 TI - Mitosis specific serine phosphorylation and downregulation of one of the focal adhesion protein, paxillin. AB - Mitotic cells typically lack well-formed focal adhesions. As an approach to explore the dynamic process regulating the focal adhesion assembly, we examined states of focal adhesion proteins during mitosis of the cell cycle. We found that the amount of paxillin was significantly reduced during mitosis of the cell cycle, whereas other focal adhesion proteins including talin, vinculin and Focal Adhesion Kinase did not. Proteolytic degradation appeared to be involved in the mitotic reduction, but transcriptional and/or translational controls of the mRNA were not essential for this downregulation. Moreover, concurrent with the decreased protein level, phosphorylation status of paxillin altered during mitosis; mitotic paxillin was phosphorylated primarily on serine and dephosphorylated on tyrosine while interphase one was phosphorylated both on serine and tyrosine. We found that mitotic phosphorylation created an electrophoretically slow-migrating population of paxillin which was barely detected in interphase cells. This mitotic specific modification occurred with both alpha and beta isoforms of paxillin. We also examined the fate of paxillin protein by changing its protein amount. We found that majority of paxillin overexpressed was subjected to the specific modification but not to the downregulation in the mitotic arrested cells. On the other hand, paxillin exogenously expressed at a moderate level was subjected to both the mitotic modification and downregulation. Collectively, we concluded that paxillin's specific serine phosphorylation together with the proteolytic downregulation of a limited fraction of paxillin is taken place during the mitosis of the cell cycle. PMID- 9362442 TI - Caspase-dependent apoptosis of COS-7 cells induced by Bax overexpression: differential effects of Bcl-2 and Bcl-xL on Bax-induced caspase activation and apoptosis. AB - Bcl-2 family proteins and ICE/CED-3 family proteases (caspases) are regarded as the basic regulators of apoptotic cell death. They are evolutionarily conserved and implicated in a variety of apoptosis. However, the precise mechanism by which these two families interact to regulate cell death is not yet known. In this study, we found that the overexpression of the Bcl-2 family member Bax induced apoptotic cell death in COS-7 cells through the activation of CPP32 (caspase-3) like proteases that cleaved the DEVD tetrapeptide. This apoptotic cell death was suppressed by the viral proteins CrmA and p35, as well as by the chemically synthesized caspase inhibitors Z-Asp-CH2-DCB and zVAD-fmk. We also found that the Bax-induced apoptosis of COS-7 cells was suppressed by Bcl-xL and Bcl-2, though both Bcl-xL and Bcl-2 similarly prevented etoposide-induced apoptosis in COS-7 cells. In addition, Bcl-xL inhibited the activation of caspase-3-like proteases accompanying Bax-induced COS-7 cell death but Bcl-2 did not. These results indicate that the caspase activation is essential for Bax-induced apoptosis, and that the ability of Bcl-2 and Bcl-xL to prevent the Bax-induced caspase activation and apoptosis in COS-7 cells could be differentially regulated. Our results also suggest that Bcl-2 family proteins function upstream of caspase activation and control apoptosis through the regulation of caspase activity. PMID- 9362443 TI - Novel BRCA1 mutations and more frequent intron-20 alteration found among 236 women from Western Poland. AB - Three different novel BRCA1 mutations, five independent cases of the same 12 bp insertion-duplication in intron-20 and two novel rare BRCA1 sequence variants were identified among 122 Polish women with positive, in most cases moderate family history of breast and/or ovarian cancer, 80 controls and 34 unselected breast cancer tissue specimens. All mutations and variants were germline. The 4153 delA frameshift mutation, the Tyr105Cys missense mutation and two cases of the alteration in intron-20 were found in the group of healthy women with positive family history. Two other cases of the intronic insertion were found in unselected controls. Their carriers had no family history of breast or ovarian cancer but other cancers occurred in their families. The 1782 Trp/STOP nonsense mutation and one case of the insertion in intron-20 were first found in tissue specimens of breast cancer patient and breast/ovarian cancer patient, respectively. Their carriers also had no family history of breast or ovarian cancer. The distribution of the insertion in intron-20 in analysed groups and results of RT-PCR experiments suggest a less prominent role for this variant considered earlier a splicing mutation. This study shows also, that more population-oriented research is needed, involving women with less profound or even no family history of breast and ovarian cancer, to better understand the role and significance of different BRCA1 variants and mutations. PMID- 9362444 TI - Developmentally-regulated expression of murine K-ras isoforms. AB - The products (p21) of the three mammalian H-, N- and K-ras genes play important roles in intracellular signal transduction, linking membrane receptor kinases to the nuclear pathway through raf and mitogen activated protein kinase. They are involved in the regulation of proliferation and differentiation, and activating mutations of these genes are commonly associated with human cancers. Two p21 proteins are encoded by the K-ras gene (p21K-rasA and p21K-rasB) due to alternative splicing of the last exon. While the four p21ras proteins are highly homologous, their sequences diverge significantly at the C-termini, to which distinct biochemical and perhaps even functional differences may be ascribed. However, H-, N- and K-rasB appear to be ubiquitously expressed, with little evidence of tissue-specific or developmental regulation. In contrast, we now demonstrate that the expression of K-rasA is strikingly different. K-rasA is induced during differentiation of pluripotent embryonal stem cells in vitro. Its expression during early embryogenesis is limited temporally and spatially in a tissue-specific distribution which is largely maintained as an adult. This suggests a distinct biological role for p21K-rasA. PMID- 9362445 TI - Overexpression of Bcl-2 inhibits alveolar cell apoptosis during involution and accelerates c-myc-induced tumorigenesis of the mammary gland in transgenic mice. AB - Expression of the apoptosis-inhibitory protein Bcl-2 has frequently been detected in human cancer including mammary carcinoma. The functional significance of its expression has been well established in experimental tumors of the lymphoid system, however, remains to be elucidated for epithelial tumors. In order to assess the role of Bcl-2 in mammary tumorigenesis we have generated WAP-bcl-2 transgenic mice. The strong overexpression of Bcl-2 in lactating mammary glands was preserved during early postlactational involution and apoptosis of alveolar epithelial cells was prevented without influencing the dedifferentiation of the milk-producing epithelium. Although Bcl-2 overexpression was not sufficient to induce spontaneous tumors it, however, led to an accelerated development of MMTV myc transgene-induced mammary tumors. In the mammary glands of MMTV myc transgenic mice, a high proportion of apoptotic cells was detected which was significantly reduced in the mammary glands of WAP-bcl-2/ MMTV myc double transgenic mice. Taken together, these results suggest that Bcl-2 contributes to mammary tumorigenesis by inhibiting apoptosis. PMID- 9362446 TI - The tetratricopeptide repeat containing Tg737 gene is a liver neoplasia tumor suppressor gene. AB - The Tg737 gene was investigated for gross alterations in a series of rodent/human liver tumors and human tumorigenic cell lines. The Tg737 gene was found to be altered in approximately 40% of the rodent chemically-induced liver tumors, 40% of the human liver tumors, and in liver, kidney and pancreatic human tumor cell lines. Ectopic re-expression of the Tg737 gene in a Tg737 deleted mouse liver tumor cell line resulted in suppression of tumorigenic growth, without altering in vitro cell culture growth. Treatment of mice which are either homozygous normal or heterozygous deleted at the Tg737 locus with the carcinogen diethylnitrosamine resulted in an increase in preneoplastic foci formation in the Tg737 heterozygous deleted mice. Ectopic expression of the Tg737 gene results in multinucleated cells, loss of Tg737 gene expression results in the proliferation of liver stem cells (oval cells) without concomitant differentiation, and reexpression of the Tg737 gene reestablished responsiveness to external differentiation factors. We believe this is the first report demonstrating tumor suppression activity for a tetratricopeptide repeat gene family member and provides insights into the function of this family of genes in mammalian cells. PMID- 9362447 TI - Distinct sensitivity of neuroblastoma cells for retinoid receptor agonists: evidence for functional receptor heterodimers. AB - Retinoic acid (RA) plays a major role in embryogenesis of the nervous system and has been reported to induce differentiation in neuroblastoma cell lines. To identify RA signaling pathways involved in such differentiation processes, two RA sensitive neuroblastoma cell lines (LA-N-5 and SH-SY5Y) were extensively studied. Northern blot experiments determined that of the three RAR mRNAs, only RARalpha was significantly expressed, with respectively weak or undetectable levels of RARgamma and RARbeta. RXRs (alpha and beta) receptors were weakly expressed. Western blotting analysis confirmed the constitutive expression of RARalpha and absence of RARbeta and weak levels of RXRalpha. Treatment with all-trans-RA up regulated RARalpha and induced a drastic increase of RARbeta (both at the RNA and protein level). To further characterize the function of RARalpha, RARbeta and RXRalpha in NB cells, nuclear extracts from LA-N-5 cells were analysed by EMSA studies. Three specific retarded complexes were observed which were significantly decreased or shifted in the presence of monoclonal antibodies to RARalpha, RARbeta and RXRalpha. RA treatment dramatically induced a DR5-binding RXRalpha RARbeta heterodimer. Treatment with combinations of RARalpha or RARbeta agonists with a RXRalpha agonist or with a RARalpha agonist alone, induced neurite outgrowth supporting the probability that both RXRalpha-RARalpha or RXRalpha RARbeta heterodimers are involved in RA-mediated differentiation of NB cells. The availability of novel synthetic RA-specific receptor ligands should provide the possibility of tissue specific therapeutic regimes. PMID- 9362448 TI - Differential effects of BCL-2 on survival and proliferation of human B-lymphoma cells following gamma-irradiation. AB - Bcl-2 can inhibit apoptosis induced by a variety of stimuli, including radiation and its presence in tumour cells would be expected to indicate poor prognosis. Bcl-2-expressing tumours, however, are often low-grade and highly responsive to therapy. To investigate this apparent paradox, we analysed in vitro the responses of Burkitt lymphoma (BL) cells to gamma-irradiation in the presence and absence of Bcl-2. High-level expression of Bcl-2 was shown to promote BL cell survival following irradiation. However, a significant proportion of Bcl-2-rescued cells subsequently underwent apoptosis after an extended period in culture. In addition, in different BL lines, Bcl-2 was found either to promote or to inhibit long-term proliferative activity following gamma-irradiation. This differential regulation of proliferation correlated both with differential effects of Bcl-2 on the cell cycle and with differences in p53 status. Thus, by one week after irradiation, BL cells expressing only wild-type p53 (wt/wt) had arrested in G1, whereas those with a mutant allele (wt/mu) were arrested in all phases of the cell cycle. The proportion of Bcl-2-rescued cells that subsequently underwent apoptosis was reduced by ligation of CD40 at the time of irradiation in wt/wt BL cells, but not in wt/mu cells. CD40-ligation reduced both G1-arrest and apoptosis in parallel. These results indicate that, whilst Bcl-2 can delay apoptosis in BL cells following gamma-irradiation, the protein can also cause growth-arrest and thereby promote apoptosis. Long-term survival following Bcl-2-mediated rescue of gamma-irradiated cells may depend on p53 status and require additional death repressing or growth-promoting signals. PMID- 9362449 TI - Induced direct binding of the adapter protein Nck to the GTPase-activating protein-associated protein p62 by epidermal growth factor. AB - The SH3-SH3-SH3-SH2 adapter protein Nck links receptor tyrosine kinases, such as EGF and PDGF receptors, to downstream signaling pathways, among which p21cdc42/rac-activated kinase cascade, Sos-activated Ras signaling and the human Wiskott-Aldrich Syndrome protein (WASp)-mediated actin cytoskeleton changes, have been implicated. In EGF stimulated cells, Nck co-immunoprecipitates with a number of phosphotyrosine proteins including the EGF receptor (Li et al., 1992 Mol. Cell. Biol. 12: 5824-2833). To identify the phosphotyrosine protein(s) that directly interacts with Nck and to distinguish it from indirectly associated proteins, preexisting phosphoytrosine protein complexes in the cell lysate were dissociated by heat and SDS prior to the test for binding to Nck. We found that Nck does not directly bind to EGF receptor, instead it binds via its SH2 domain to a 62 kDa phosphotyrosine protein. We present evidence demonstrating that the Nck-bound p62 is related to the previously identified GTPase-activating protein (GAP)-associated phosphotyrosine protein p62. (1) The Nck-bound and the GAP-bound p62 proteins co-migrate with each other in SDS-PAGE. (2) SH2 domains from Nck and GAP compete for binding to p62 in vitro. (3) Purified GST-Nck-SH2 binds directly to the GAP-associated p62. Under these conditions, SH2 domains from PLCgamma, PI 3 kinase, SHC, and Grb2 did not bind p62. (4) Tryptic phosphopeptide maps of the Nck- and the GAP-associated p62 proteins are identical. However, Nck and GAP do not co-immunoprecipitate with each other and apparently bind to different pools of p62. This study suggests that the GAP-associated p62 acts as an SH2 domain docking protein and mediates the interaction between Nck and EGF receptor in response to EGF stimulation. PMID- 9362450 TI - Roles of the Pas1 and Par2 genes in determination of the unique, intermediate susceptibility of BALB/cByJ mice to urethane-induction of lung carcinogenesis: differential effects on tumor multiplicity, size and Kras2 mutations. AB - The C3H/HeJ (C3H), A/J and BALB/cByJ (BALB) mouse strains are respectively resistant, sensitive and intermediate regarding the induction of lung tumors by urethane. The phenotypic difference between C3H and A/J is largely determined by the Pas1 (Pulmonary adenoma susceptibility 1) gene on chromosome 6, the A/J allele of which dominantly increases the tumor burden. We recently found that BALB mice possess a unique lung tumor resistance gene on chromosome 18, designated Par2 (Pulmonary adenoma resistance 2), which partially, but dominantly suppresses the sensitive phenotype of A/J mice (Oncogene 13: 1599-1604, 1996). It has, however, remained unclear why BALB mice carrying the Par2 gene are significantly more sensitive to urethane-induced lung carcinogenesis than C3H mice that have no dominant lung tumor resistance genes. In the present study, using (C3H x BALB)F1 x C3H backcross mice treated with urethane, we demonstrated that BALB mice possess the disease allele of the Pas1 gene despite their 15-fold more resistance relative to A/J mice (LOD = 22.6). The BALB Par2 allele only significantly reduced the mean lung tumor multiplicity (LOD = 4.4) in the backcross population carrying the BALB allele of Pas1, indicating that the intermediate BALB phenotype may at least in part be the result of interactions between these two dominant genes. While the BALB Pas1 allele increased both the mean multiplicity and size of lung tumors, the BALB Par2 allele affected only the mean tumor multiplicity, implying that they are involved in different stages of multi-step lung carcinogenesis. In addition, we found that 68% of lung tumors from the BALB Pas1-positive backcross mice contained activating point mutations of the Kras2 oncogene, tightly linked to the Pas1 locus, whereas these genetic alterations were absent in tumors from BALB Pas1-negative mice. The Par2 genotype exhibited no effect on this parameter. Since the activating point mutations were observed exclusively in the BALB allele as already reported with lung tumors in (C57BL/6J x BALB/cJ)F1 mice, BALB Pas1 or possibly Kras2 itself may confer selective growth advantage on the affected urethane-initiated lung lesions. PMID- 9362451 TI - The carboxy-terminus of I kappaB alpha determines susceptibility to degradation by the catalytic core of the proteasome. AB - The Rel/NF-kappaB family of transcription factors controls the expression of a wide variety of genes that are implicated in immune and inflammatory responses and cellular proliferation. Disregulation of NF-kappaB is associated with cellular transformation and the maintenance of a high anti-apoptotic threshold in transformed cells. NF-kappaB activity is in turn regulated by its sequestration in the cytoplasm by the inhibitor I kappaB. I kappaB alpha, the most abundant and well-characterized member of the I kappaB multiprotein family, is rapidly degraded in response to multiple physiologic stimuli. In the present study we show that not only the amino-terminus, but also the carboxy-terminus of I kappaB alpha contain transferable signals that must be simultaneously present in an unrelated protein to render it susceptible to activation-induced, proteasome mediated degradation. We show here that I kappaB alpha amino-terminal modifications occur independently of the carboxy-terminus. Moreover, we present evidence indicating a critical role for the carboxy-terminal region in facilitating proteolysis by the catalytic core of the proteasome. When incubated with 20S proteasome extracted from rat liver, I kappaB alpha was quickly degraded while a deletion mutant lacking the carboxy-terminus was resistant to proteolysis. Likewise, chimeric proteins of beta-galactosidase with the I kappaB alpha carboxy-terminus were degraded in vitro independently of the presence of the I kappaB alpha amino-terminus, whereas chimeric proteins lacking the I kappaB alpha carboxy-terminus were stable. Our results identify the carboxy-terminus of I kappaB alpha as a domain critical for degradation through interaction with an as yet unidentified component of the proteasome. PMID- 9362452 TI - Epstein-Barr virus latent membrane protein-1 (LMP1) C-terminus activation region 2 (CTAR2) maps to the far C-terminus and requires oligomerisation for NF-kappaB activation. AB - The Epstein-Barr virus Latent Membrane Protein-1 (LMP1) has structural features and functions consistent with it being a constitutively active cell surface receptor. The known association of LMP1 with members of the TRAF family of proteins suggests that LMP1 transduces signals similarly to the Tumour Necrosis Factor Receptor (TNFR) family of cell surface receptors that signal by forming dimers or trimers in response to binding of extracellular ligands. However, interactions between LMP1 and the TRAFs have so far only been described for the C terminal activation region 1 (CTAR1) of LMP1 and no direct interactions of the TRAFs with the second NF-kappaB activation domain (CTAR2) have been reported. We have now mapped the NF-kappaB activation domain of CTAR2 to a highly conserved stretch of 6 amino acids at the far C-terminus (codons 379 to 384 in B95.8 LMP1). In addition, we constructed chimeric receptor molecules which contain the ligand binding extracellular domain and the transmembrane domain of rat CD2 fused to the C-terminus of LMP1 encoding the CTAR1 and/or the CTAR2 domain. Interestingly, the function of a chimera encoding CTAR2 alone, as well as the function of a chimera encoding both CTAR1 and CTAR2 was found to be inducible upon antibody-mediated crosslinking. These inducible chimeric proteins also allowed us to demonstrate that LMP1 mediated NF-kappaB activation is an immediate event following activation of LMP1. PMID- 9362453 TI - cAMP-induced NF-kappaB (p50/relB) binding to a c-myb intronic enhancer correlates with c-myb up-regulation and inhibition of erythroleukemia cell differentiation. AB - During hexamethylene bisactamide (HMBA)-induced differentiation of murine erythroleukemia (MEL) cells erythroid genes are transcriptionally activated while c-myb and several other nuclear proto-oncogenes are down-regulated. Differentiation is inhibited by cAMP analogues and the adenyl cyclase-stimulating agent forskolin. We found that these drugs prevented the late down-regulation of c-myb which is known to be critical for MEL cell differentiation. Since the increase in c-myb mRNA levels was due to increased mRNA transcription, we examined the transcription factors NF-kappaB and AP-1 which have been implicated in the regulation of c-myb expression. Binding of MEL cell nuclear proteins to a NF-kappaB recognition sequence in c-myb intron I was strongly induced by 8-Br cAMP or forskolin; induction was delayed and correlated with the up-regulation of c-myb. The cAMP-induced NF-kappaB complex contained p50 and RelB; in co transfection assays, p50 and RelB transactivated a reporter construct containing the c-myb intronic NF-kappaB site upstream of a minimal promoter. 8-Br-cAMP and forskolin also increased the DNA binding activity of AP-1 complexes containing JunB, JunD and c-Fos in MEL cells which could cooperate with NF-kappaB. We conclude that inhibition of MEL cell differentiation by pharmacological doses of cAMP can be explained by the up-regulation of c-myb which is mediated, at least in part, by NF-kappaB p50/RelB heterodimers. PMID- 9362454 TI - Bak can accelerate chemotherapy-induced cell death independently of its heterodimerization with Bcl-XL and Bcl-2. AB - Bak has been shown to both promote apoptosis and to inhibit cell death while two other members of the Bcl-2 family of proteins, Bcl-XL and Bcl-2 delay apoptosis induced by various stimuli including chemotherapeutic agents. We generated clones with stable expression of Bak wild-type (wt) and Bak with its BH3 (delta78-86) domain deleted (deltaBH3) in FL5.12 cells or FL5.12 cells expressing either Bcl XL or Bcl-2 to determine if Bak could accelerate apoptosis and antagonize the death repressor activity of Bcl-XL and Bcl-2 during chemotherapy-induced apoptosis. We found that Bak accelerated cell death in FL5.12 cells treated with etoposide, fluorouracil or taxol. In FL5.12 cells expressing Bcl-XL and Bak wt or Bak deltaBH3, both Bak wt or Bak deltaBH3 were able to antagonize the protective effect of Bcl-XL when treated with etoposide or fluorouracil. Bak wt or Bak deltaBH3 were also able to abrogate the protective effect of Bcl-2 in cells expressing Bcl-2 and Bak wt or Bak deltaBH3 when challenged by etoposide or fluorouracil. Immunoprecipitation studies revealed that deletion of BH3 disrupted heterodimerization between Bak and Bcl-XL and that both Bak wt and Bak deltaBH3 failed to interact with Bcl-2. These results demonstrate that Bak does not require its BH3 domain to promote apoptosis in stably transfected cells. Furthermore, Bak can accelerate chemotherapy-induced cell death independently of its heterodimerization with Bcl-XL and Bcl-2. PMID- 9362455 TI - The Drosophila toucan (toc) gene is required in germline cells for the somatic cell patterning during oogenesis. AB - We have characterized a new gene, called toucan, that is expressed and required in germline cells to promote proper differentiation of the somatic follicle cells. toucan mutant ovaries are defective in (i) the enclosure of newly formed germline cysts by the follicle cells, (ii) the formation of interfollicular stalks, (iii) the migration of the follicle cells over the oocyte and (iv) the formation of the eggshell. Overexpression of a toucan cDNA in the germline leads to the production of longer interfollicular stalks than wild-type ovaries, a phenotype that is the exact opposite of the toucan mutant phenotype. This observation shows that the formation of the interfollicular stalks depends not only on interactions among the somatic cells but also requires a germline signal. Moreover, dominant interactions have been observed between toucan and certain alleles of the daughterless, Notch and Delta genes, each of which is required in the somatic cells for the formation of egg chambers. toucan encodes for a large protein with a coiled-coil domain but has no other homology with known proteins. We propose that toucan participates in the production or localization of a germline-specific signal(s) that is required for the patterning of the follicular epithelium. PMID- 9362456 TI - Oocyte determination and the origin of polarity in Drosophila: the role of the spindle genes. AB - The two main body axes in Drosophila become polarised as a result of a series of symmetry-breaking steps during oogenesis. Two of the sixteen germline cells in each egg chamber develop as pro-oocytes, and the first asymmetry arises when one of these cells is selected to become the oocyte. Anterior-posterior polarity originates when the oocyte then comes to lie posterior to the nurse cells and signals through the Gurken/Egfr pathway to induce the adjacent follicle cells to adopt a posterior fate. This directs the movement of the germinal vesicle and associated gurken mRNA from the posterior to an anterior corner of the oocyte, where Gurken protein signals for a second time to induce the dorsal follicle cells, thereby polarising the dorsal-ventral axis. Here we describe a group of five genes, the spindle loci, which are required for each of these polarising events. spindle mutants inhibit the induction of both the posterior and dorsal follicle cells by disrupting the localisation and translation of gurken mRNA. Moreover, the oocyte often fails to reach the posterior of mutant egg chambers and differentiates abnormally. Finally, double mutants cause both pro-oocytes to develop as oocytes, by delaying the choice between these two cells. Thus, these mutants reveal a novel link between oocyte selection, oocyte positioning and axis formation in Drosophila, leading us to propose that the spindle genes act in a process that is common to several of these events. PMID- 9362457 TI - FIGalpha, a germ cell specific transcription factor involved in the coordinate expression of the zona pellucida genes. AB - The mouse zona pellucida is composed of three glycoproteins, ZP1, ZP2 and ZP3, encoded by single-copy genes whose expression is temporally and spatially restricted to oocytes. All three proteins are required for the formation of the extracellular zona matrix and female mice with a single disrupted zona gene lack a zona and are infertile. An E-box (CANNTG), located approximately 200 bp upstream of the transcription start sites of Zp1, Zp2 and Zp3, forms a protein DNA complex present in oocytes and, to a much lesser extent, in testes. It has been previously shown that the integrity of this E-box in Zp2 and Zp3 promoters is required for expression of luciferase reporter genes microinjected into growing oocytes. The presence of the ubiquitous transcription factor E12 in the complex was used to identify a novel basic helix-loop-helix protein, FIGalpha (Factor In the Germline alpha) whose expression was limited to oocytes within the ovary. The ability of FIGalpha to transactivate reporter genes coupled to each of the three mouse zona promoters in heterologous 10T(1/2) embryonic fibroblasts suggests a role in coordinating the expression of the three zona pellucida genes during oogenesis. PMID- 9362458 TI - CNS midline cells in Drosophila induce the differentiation of lateral neural cells. AB - Cells located at the midline of the developing central nervous system perform a number of conserved functions during the establishment of the lateral CNS. The midline cells of the Drosophila CNS were previously shown to be required for correct pattern formation in the ventral ectoderm and for the induction of specific mesodermal cells. Here we investigated whether the midline cells are required for the correct development of lateral CNS cells as well. Embryos that lack midline cells through genetic ablation show a 15% reduction in the number of cortical CNS cells. A similar thinning of the ventral nerve cord can be observed following mechanical ablation of the midline cells. We have identified a number of specific neuronal and glial cell markers that are reduced in CNS midline-less embryos (in single-minded embryos, in early heat-shocked Notch(ts1) embryos or in embryos where we mechanically ablated the midline cells). Genetic data suggest that both neuronal and glial midline cell lineages are required for differentiation of lateral CNS cells. We could rescue the lateral CNS phenotype of single-minded mutant embryos by transplantation of midline cells as well as by homotopic expression of single-minded, the master gene for midline development. Furthermore, ectopic midline cells are able to induce enhanced expression of some lateral CNS cell markers. We thus conclude that the CNS midline plays an important role in the differentiation or maintenance of the lateral CNS cortex. PMID- 9362459 TI - Early specification and autonomous development of cortical fields in the mouse hippocampus. AB - Studies of the specification of distinct areas in the developing cerebral cortex have until now focused mainly on neocortex. We demonstrate that the hippocampus, an archicortical structure, offers an elegant, alternative system in which to explore cortical area specification. Individual hippocampal areas, called CA fields, display striking molecular differences in maturity. We use these distinct patterns of gene expression as markers of CA field identity, and show that the two major hippocampal fields, CA1 and CA3, are specified early in hippocampal development, during the period of neurogenesis. Two field-specific markers display consistent patterns of expression from the embryo to the adult. Presumptive CA1 and CA3 fields (Pca1, Pca3) can therefore be identified between embryonic days 14.5 and 15.5 in the mouse, a week before the fields are morphologically distinct. No other individual cortical areas have been detected by gene expression as early in development. Indeed, other features that distinguish between the CA fields appear after birth, indicating that mature CA field identity is acquired over at least 3 weeks. To determine if Pca1 and Pca3 are already specified to acquire mature CA field identities, the embryonic fields were isolated from further potential specification cues by maintaining them in slice culture. CA field development proceeds in slices of the entire embryonic hippocampus. More strikingly, slices restricted to Pca1 or Pca3 alone also develop appropriate mature features of CA1 or CA3. Pca1 and Pca3 are therefore able to develop complex characteristics of mature CA field identity autonomously, that is, without contact or innervation from other fields or other parts of the brain. Because Pca1 and Pca3 can be identified before major afferents grow into the hippocampus, innervation may also be unnecessary for the initial division of the hippocampus into separate fields. Providing a clue to the source of the true specifying signals, the earliest field markers appear first at the poles of the hippocampus, then progress inwards. General hippocampal development does not follow this pronounced pattern. We suggest that the sources of signals that specify hippocampal field identity lie close to the hippocampal poles, and that the signals operate first on cells at the poles, then move inwards. PMID- 9362460 TI - Emergence of determined myotome precursor cells in the somite. AB - Myotome and sclerotome precursor cells are derived, respectively, from cells in the dorsomedial and ventromedial regions of the somite. To assay changes in the specification of myotomal precursor cells during somite maturation, we implanted dorsomedial quadrant fragments, from staged quail somites, next to the notochords of host chick embryos, and superimposed two additional notochords on these implants. In this notochord signalling environment, dorsomedial quadrant cells that are developmentally plastic are expected to differentiate as cartilage, while cells determined to a myogenic fate are expected to differentiate as skeletal muscle. Large numbers of differentiated chondrocytes developed from dorsomedial quadrant grafts of all stages of paraxial mesoderm development tested, indicating that persistent chondrogenic potential in cells fated to form muscle and dermis can be elicited by notochord signals. Differentiated myocytes, however, appeared in two somite-stage-dependent phases. In the first phase, dorsomedial quadrants from segmental plate and early stage somites (II and IV) form small, disorganized clusters of individual myocytes. The frequency of first phase myocluster formation increases as myogenic factor expression begins in the dorsomedial quadrant, indicating that myogenic determination assayed by this method is closely linked to the expression of myogenic factors in the dorsomedial quadrant. In the second phase, dorsomedial quadrants from somite stages XI-XIII consistently form morphologically organized muscle tissue containing large numbers of parallel-oriented, multinucleated myotubes. Mitotic labelling demonstrated that muscle precursors were determined to the muscle phenotype prior to withdrawal from the cell cycle. Thus, myogenic determination in cells of the dorsomedial quadrant is acquired at earlier stages of somite maturation than the ability to proliferate and form muscle tissue. These results are consistent with the hypothesis that successive lineages of myotome precursor cells with different mitotic and morphogenetic properties arise in the dorsomedial quadrant during somite maturation. PMID- 9362462 TI - Two copies of a subelement from the Vg1 RNA localization sequence are sufficient to direct vegetal localization in Xenopus oocytes. AB - Localization of mRNA has emerged as a fundamental mechanism for generating polarity during development. In vertebrates, one example of this phenomenon is Vg1 RNA, which is localized to the vegetal cortex of Xenopus oocytes. Vegetal localization of Vg1 RNA is directed by a 340-nt sequence element contained within its 3' untranslated region. To investigate how such cis-acting elements function in the localization process, we have undertaken a detailed analysis of the precise sequence requirements for vegetal localization within the 340-nt localization element. We present evidence for considerable redundancy within the localization element and demonstrate that critical sequences lie at the ends of the element. Importantly, we show that a subelement from the 5' end of the Vg1 localization element is, when duplicated, sufficient to direct vegetal localization. We suggest that the Vg1 localization element is composed of smaller, redundant sequence motifs and identify one such 6-nt motif as essential for localization. These results allow insight into what constitutes an RNA localization signal and how RNA sequence elements may act in the localization process. PMID- 9362461 TI - ErbB3 is required for normal cerebellar and cardiac development: a comparison with ErbB2-and heregulin-deficient mice. AB - Heregulins bind directly to ErbB3 and ErbB4 receptors, leading to multiple dimerization possibilities including heterodimerization with the ErbB2 receptor. We have generated ErbB3-, ErbB2- and heregulin-deficient mice to assess their roles in development and differentiation. Heregulin(-/-) and ErbB2(-/-) embryos died on E10.5 due to a lack of cardiac ventricular myocyte differentiation; ErbB3(-/-) embryos survived until E13.5 exhibiting cardiac cushion abnormalities leading to blood reflux through defective valves. In ErbB3(-/-) embryos, the midbrain/hindbrain region was strikingly affected, with little differentiation of the cerebellar plate. Cranial ganglia defects, while present in all three nulls, were less severe in ErbB3(-/-) embryos. The cranial ganglia defects, along with a dramatic reduction in Schwann cells, enteric ganglia and adrenal chromaffin cells, suggests a generalized effect on the neural crest. Numerous organs, including the stomach and pancreas also exhibited anomalous development. PMID- 9362464 TI - A role for netrin-1 in the guidance of cortical efferents. AB - An intermediate target for axons leaving the cerebral cortex in embryonic mammals is the ganglionic eminence (GE), the embryonic precursor of the basal ganglia. The cues that direct these axons over the initial portion of their trajectory are not well understood, but could include both short-range and long-range attractants and repellents. In the present study, we provide evidence that corticofugal axons might be guided at least partly by a diffusible factor or factors originating in the lateral GE and the sulcus between the lateral and medial ridges of the GE (ISS), as well as evidence implicating the axonal chemoattractant netrin-1 in mediating these effects. Explants of lateral GE and ISS obtained from E12.5 and E13.5 mouse forebrain have a strong effect on both the outgrowth and orientation of corticofugal axons when cultured at a distance with explants of embryonic cortex in collagen gels. Netrin-1 mRNA is detected in these target tissues by in situ hybridization, and both netrin-1 protein and heterologous cells secreting netrin-1 can mimic the outgrowth-promoting effect of these target tissues in vitro. Furthermore, the growth of corticofugal axons is oriented toward an ectopic source of netrin-1 in vitro, and a function blocking anti-netrin-1 antiserum specifically abolishes the cortical axon outgrowth elicited by explants of lateral GE and the ISS in collagen gel cocultures. Taken together, these results suggest a role for netrin-1 in the attraction at a distance of early cortical axons by the GE. Thus in mammals -- as is also observed in nematodes -- the development of non-commissural projections in anterior regions of the embryo might be directed by mechanisms similar to those involved in directing the development of commissural projections in more posterior regions of the central nervous system. PMID- 9362463 TI - Novel regulatory interactions revealed by studies of murine limb pattern in Wnt 7a and En-1 mutants. AB - Classical embryological experiments have demonstrated that dorsal-ventral patterning of the vertebrate limb is dependent upon ectodermal signals. One such factor is Wnt-7a, a member of the Wnt family of secreted proteins, which is expressed in the dorsal ectoderm. Loss of Wnt-7a results in the appearance of ventral characteristics in the dorsal half of the distal limb. Conversely, En-1, a homeodomain transcription factor, is expressed exclusively in the ventral ectoderm, where it represses Wnt-7a. En-1 mutants have dorsal characteristics in the ventral half of the distal limb. Experiments in the chick suggest that the dorsalizing activity of Wnt-7a in the mesenchyme is mediated through the regulation of the LIM-homeodomain transcription factor Lmx-1. Here we have examined the relationship between Wnt-7a, En-1 and Lmx-1b, a mouse homolog of chick Lmx-1, in patterning the mammalian limb. We find that Wnt-7a is required for Lmx-1b expression in distal limb mesenchyme, and that Lmx-1b activation in the ventral mesenchyme of En-1 mutants requires Wnt-7a. Consistent with Lmx-1b playing a primary role in dorsalization of the limb, we find a direct correlation between regions of the anterior distal limb in which Lmx-lb is misregulated during limb development and the localization of dorsal-ventral patterning defects in Wnt-7a and En-1 mutant adults. Thus, ectopic Wnt-7a expression and Lmx-1b activation underlie the dorsalized En-1 phenotype, although our analysis also reveals a Wnt-7a-independent activity for En-1 in the repression of pigmentation in the ventral epidermis. Finally, we demonstrate that ectopic expression of Wnt 7a in the ventral limb ectoderm of En-1 mutants results in the formation of a second, ventral apical ectodermal ridge (AER) at the junction between Wnt-7a expressing and nonexpressing ectoderm. Unlike the normal AER, ectopic AER formation is dependent upon Wnt-7a activity, indicating that distinct genetic mechanisms may be involved in primary and secondary AER formation. PMID- 9362465 TI - Deficient development and maintenance of postsynaptic specializations in mutant mice lacking an 'adult' acetylcholine receptor subunit. AB - At many synapses, 'fetal' neurotransmitter receptor subunits are replaced by 'adult' subunits as development proceeds. To assess the significance of such transitions, we deleted the gene encoding the adult acetylcholine receptor (AChR) epsilon subunit, which replaces its fetal counterpart, the gamma subunit, at the skeletal neuromuscular junction during early postnatal life. Several aspects of postnatal maturation, including synapse elimination, proceeded normally in the absence of the adult AChR, but structural development of the endplate was compromised. Later, inadequate compensation by the gamma subunit led to severely reduced AChR density in mutant endplates relative to controls. This decreased density led to a profound reorganization of AChR-associated components of the postsynaptic membrane and cytoskeleton. Together, these results suggest novel roles for AChRs in assembly of the postsynaptic apparatus. PMID- 9362467 TI - Sectors expressing the homeobox gene liguleless3 implicate a time-dependent mechanism for cell fate acquisition along the proximal-distal axis of the maize leaf. AB - The longitudinal axis of the maize leaf is composed of, in proximal to distal order, sheath, ligule, auricle and blade. The semidominant Liguleless3-O (Lg3-O) mutation disrupts leaf development at the ligular region of the leaf midrib by transforming blade to sheath. In a previous study, we showed that leaf sectors of Lg3 mutant activity are cell nonautonomous in the transverse dimension and can confer several alternative developmental fates (Fowler, Muehlbauer and Freeling (1996) Genetics 143, 489-503). In our present study we identify five Lg3 sector types in the leaf: sheath-like with displaced ligule (sheath-like), sheath-like with ectopic ligule (ectopic ligule), auricle-like, macro-hairless blade and wild type blade. The acquisition of a specific sector fate depends on the timing of Lg3 expression. Early Lg3 expression results in adoption of the sheath-like phenotype at the ligule position (a proximal cell fate), whereas later Lg3 expression at the same position results in one of the more distal cell fates. Furthermore, sheath-like Lg3 sectors exhibit a graded continuum of phenotypes in the transformed blade region from the most proximal (sheath) to the most distal (wild-type blade), suggesting that cell fate acquisition is a gradual process. We propose a model for leaf cell fate acquisition based on a timing mechanism whereby cells of the leaf primordium progress through a maturation schedule of competency stages which eventually specify the cell types along the proximal to distal axis of the leaf. In addition, the lateral borders between Lg3 'on' sectors and wild-type leaf sometimes provide evidence of no spreading of the transformed phenotype. In these cases, competency stages are inherited somatically. PMID- 9362466 TI - Determination of the migratory capacity of embryonic cortical cells lacking the transcription factor Pax-6. AB - The cerebral cortex forms by the orderly migration and subsequent differentiation of neuronal precursors generated in the proliferative ventricular zone. We studied the role of the transcription factor Pax-6, which is expressed in the ventricular zone, in cortical development. Embryos homozygous for a mutation of Pax-6 (Small eye; Sey) had abnormalities suggesting defective migration of late born cortical precursors. When late-born Sey/Sey precursors were transplanted into wild-type embryonic rat cortex, they showed similar integrative, migrational and differentiative abilities to those of transplanted wild-type mouse precursors. These results suggest that postmitotic cortical cells do not need Pax 6 to acquire the capacity to migrate and differentiate, but that Pax-6 generates a cortical environment that permits later-born precursors to express their full developmental potential. PMID- 9362468 TI - Analysis of the mechanism(s) of metaphase I arrest in strain LT mouse oocytes: participation of MOS. AB - Oocytes of almost all vertebrates become arrested at metaphase II to await fertilization. Arrest is achieved with the participation of a protein complex known as cytostatic factor (CSF) that stabilizes histone H1 kinase activity. MOS and mitogen-activated protein kinase (MAPK) are important components of CSF. Strain LT/Sv mice, and strains related to LT/Sv, produce a high percentage of atypical oocytes that are arrested at metaphase I when normal oocytes have progressed to metaphase II. The potential role of MOS in metaphase I arrest was investigated using strain LT/Sv and LT-related recombinant inbred strains, LTXBO and CX8-4. MOS and MAPK are produced and functional in maturing LT oocytes. Two experimental paradigms were used to reduce or delete MOS in LT oocytes and assess effects on metaphase I arrest. First, sense and antisense Mos oligonucleotides were microinjected into metaphase I-arrested oocytes. Antisense, but not sense, Mos oligonucleotides promoted the activation of metaphase I-arrested oocytes. Second, mice carrying a Mos null mutation were crossed with LT mice, the null mutation was backcrossed three times to LT mice, and Mos(+/-) N3 mice were intercrossed to produce Mos(-/-), Mos(+/-) and Mos(+/+) N3F1 mice. Oocytes of all three Mos genotypes of N3F1 mice sustained meiotic arrest for 17 hours indicating that metaphase I arrest is not initiated by a MOS-dependent mechanism. However, unlike Mos(+/+) and Mos(+/-) CX8-4 N3F1 oocytes, metaphase I arrest of Mos(-/-) CX8-4 N3F1 oocytes was not sustained after 17 hours and became reversed gradually. These results, like the antisense Mos oligonucleotide microinjection experiments, suggest that MOS participates in sustaining metaphase I arrest in LT oocytes. PMID- 9362469 TI - Cellular and axonal migrations are misguided along both body axes in the maternal effect mau-2 mutants of Caenorhabditis elegans. AB - We have characterized the mau-2 mutants of Caenorhabditis elegans and found that migrating cells and axons are mispositioned along both the antero-posterior and dorsoventral body axes. This is in contrast to previously characterized guidance mutations in Caenorhabditis and in Drosophila, which have been found to be axis specific. Two observations suggest that mau-2 acts very early during development: most behavioral phenotypes of mau-2 can be rescued by a maternal effect, and variations in expressivity involve an entire body side at a time. The possibility that mau-2 is involved in the spatial organization of guidance cues encoded by other genes is discussed. PMID- 9362470 TI - Misexpression of chick Vg1 in the marginal zone induces primitive streak formation. AB - In the chick embryo, the primitive streak is the first axial structure to develop. The initiation of primitive streak formation in the posterior area pellucida is influenced by the adjacent posterior marginal zone (PMZ). We show here that chick Vg1 (cVg1), a member of the TGFbeta family of signalling molecules whose homolog in Xenopus is implicated in mesoderm induction, is expressed in the PMZ of prestreak embryos. Ectopic expression of cVg1 protein in the marginal zone chick blastoderms directs the formation of a secondary primitive streak, which subsequently develops into an ectopic embryo. We have used cell marking techniques to show that cells that contribute to the ectopic primitive streak change fate, acquiring two distinct properties of primitive streak cells, defined by gene expression and cell movements. Furthermore, naive epiblast explants exposed to cVg1 protein in vitro acquire axial mesodermal properties. Together, these results show that cVg1 can mediate ectopic axis formation in the chick by inducing new cell fates and they permit the analysis of distinct events that occur during primitive streak formation. PMID- 9362471 TI - Vitronectin is expressed in the ventral region of the neural tube and promotes the differentiation of motor neurons. AB - The extracellular matrix protein vitronectin and its mRNA are present in the embryonic chick notochord, floor plate and in the ventral neural tube at the time position of motor neuron generation. When added to cultures of neural tube explants of developmental stage 9, vitronectin promotes the generation of motor neurons in the absence of either notochord or exogenously added Sonic hedgehog. Conversely, the neutralisation of endogenous vitronectin with antibodies inhibits over 90% motor neuron differentiation in co-cultured neural tube/notochord explants, neural tube explants cultured in the presence of Sonic hedgehog, and in committed (stage 13) neural tube explants. Furthermore, treatment of embryos with anti-vitronectin antibodies results in a substantial and specific reduction in the number of motor neurons generated in vivo. These results demonstrate that vitronectin stimulates the differentiation of motor neurons in vitro and in vivo. Since the treatment of stage 9 neural tube explants with Sonic hedgehog resulted in induction of vitronectin mRNA expression before the expression of floor plate markers, we conclude that vitronectin may act either as a downstream effector in the signalling cascade induced by Sonic hedgehog, or as a synergistic factor that increases Shh-induced motor neuron differentiation. PMID- 9362472 TI - Functional analysis of an ascidian homologue of vertebrate Bmp-2/Bmp-4 suggests its role in the inhibition of neural fate specification. AB - The ascidian tadpole larva is thought to be close to a prototype of the ancestral chordate. The vertebrate body plan is established by a series of inductive cellular interactions, whereas ascidians show a highly determinate mode of development. Recent studies however, suggest some roles of cell-cell interaction during ascidian embryogenesis. To elucidate the signaling molecules responsible for the cellular interaction, we isolated HrBMPb, an ascidian homologue of the vertebrate bone morphogenetic protein (BMP) gene, from Halocynthia roretzi. The amino acid sequence of HrBMPb closely resembled those of vertebrate BMP-2 and BMP 4 and of Drosophila Decapentaplegic (DPP). In addition to the sequence similarity, HrBMPb overexpression induced the ventralization of Xenopus embryos, suggesting functional conservation. The zygotic expression of HrBMPb was first detected around gastrulation. HrBMPb expression was maintained in some cells at the lateral edges of the neural plate through gastrulation to neurulation, although that in the presumptive muscle cells was downregulated. HrBMPb was not expressed in the presumptive epidermis during gastrulation. When HrBMPb mRNA was injected into fertilized Halocynthia eggs, cells that normally give rise to the neural tissue differentiated into epidermis, causing a loss of anterior neural tissue in the larva. In addition, HrBMPb might function synergistically with HrBMPa, an ascidian homologue of BMPs-5 to 8. However, HrBMPb overexpression did not affect differentiation of the notochord and muscle cells. These results suggest that HrBMPb functions as a neural inhibitor and as an epidermal inducer but not as a ventralizing agent in ascidian development. PMID- 9362473 TI - Regulation of the twist target gene tinman by modular cis-regulatory elements during early mesoderm development. AB - The Drosophila tinman homeobox gene has a major role in early mesoderm patterning and determines the formation of visceral mesoderm, heart progenitors, specific somatic muscle precursors and glia-like mesodermal cells. These functions of tinman are reflected in its dynamic pattern of expression, which is characterized by initial widespread expression in the trunk mesoderm, then refinement to a broad dorsal mesodermal domain, and finally restricted expression in heart progenitors. Here we show that each of these phases of expression is driven by a discrete enhancer element, the first being active in the early mesoderm, the second in the dorsal mesoderm and the third in cardioblasts. We provide evidence that the early-active enhancer element is a direct target of twist, a gene encoding a basic helix-loop-helix (bHLH) protein, which is necessary for tinman activation. This 180 bp enhancer includes three E-box sequences which bind Twist protein in vitro and are essential for enhancer activity in vivo. Ectodermal misexpression of twist causes ectopic activation of this enhancer in ectodermal cells, indicating that twist is the only mesoderm-specific activator of early tinman expression. We further show that the 180 bp enhancer also includes negatively acting sequences. Binding of Even-skipped to these sequences appears to reduce twist-dependent activation in a periodic fashion, thus producing a striped tinman pattern in the early mesoderm. In addition, these sequences prevent activation of tinman by twist in a defined portion of the head mesoderm that gives rise to hemocytes. We find that this repression requires the function of buttonhead, a head-patterning gene, and that buttonhead is necessary for normal activation of the hematopoietic differentiation gene serpent in the same area. Together, our results show that tinman is controlled by an array of discrete enhancer elements that are activated successively by differential genetic inputs, as well as by closely linked activator and repressor binding sites within an early-acting enhancer, which restrict twist activity to specific areas within the twist expression domain. PMID- 9362474 TI - Induction of female Sex-lethal RNA splicing in male germ cells: implications for Drosophila germline sex determination. AB - With a focus on Sex-lethal (Sxl), the master regulator of Drosophila somatic sex determination, we compare the sex determination mechanism that operates in the germline with that in the soma. In both cell types, Sxl is functional in females (2X2A) and nonfunctional in males (1X2A). Somatic cell sex is determined initially by a dose effect of X:A numerator genes on Sxl transcription. Once initiated, the active state of SXL is maintained by a positive autoregulatory feedback loop in which Sxl protein insures its continued synthesis by binding to Sxl pre-mRNA and thereby imposing the productive (female) splicing mode. The gene splicing-necessary factor (snf), which encodes a component of U1 and U2 snRNPs, participates in this RNA splicing control. Here we show that an increase in the dose of snf+ can trigger the female Sxl RNA splicing mode in male germ cells and can feminize triploid intersex (2X3A) germ cells. These snf+ dose effects are as dramatic as those of X:A numerator genes on Sxl in the soma and qualify snf as a numerator element of the X:A signal for Sxl in the germline. We also show that female-specific regulation of Sxl in the germline involves a positive autoregulatory feedback loop on RNA splicing, as it does in the soma. Neither a phenotypically female gonadal soma nor a female dose of X chromosomes in the germline is essential for the operation of this feedback loop, although a female X-chromosome dose in the germline may facilitate it. Engagement of the Sxl splicing feedback loop in somatic cells invariably imposes female development. In contrast, engagement of the Sxl feedback loop in male germ cells does not invariably disrupt spermatogenesis; nevertheless, it is premature to conclude that Sxl is not a switch gene in germ cells for at least some sex-specific aspects of their differentiation. Ironically, the testis may be an excellent organ in which to study the interactions among regulatory genes such as Sxl, snf, ovo and otu which control female-specific processes in the ovary. PMID- 9362475 TI - Genetic characterization of the role of the two HOX proteins, Proboscipedia and Sex Combs Reduced, in determination of adult antennal, tarsal, maxillary palp and proboscis identities in Drosophila melanogaster. AB - Both Proboscipedia (PB) and Sex Combs Reduced (SCR) activities are required for determination of proboscis identity. Here we show that simultaneous removal of PB and SCR activity results in a proboscis-to-antenna transformation. Dominant negative PB molecules inhibit the activity of SCR indicating that PB and SCR interact in a multimeric protein complex in determination of proboscis identity. These data suggest that the expression pattern of PB and SCR and the ability of PB and SCR to interact in a multimeric complex control the determination of four adult structures. The absence of PB and SCR expression leads to antennal identity; expression of only PB leads to maxillary palp identity; expression of only SCR leads to tarsus identity; and expression of both PB and SCR, which results in the formation of a PB-SCR-containing complex, leads to proboscis identity. However, the PB-SCR interaction is not detectable in vitro and is not detectable genetically in the head region during embryogenesis, indicating the PB SCR interaction may be regulated and indirect. This regulation may also explain why ectopic expression of SCR(Q50K) and SCR do not result in the expected transformation of the maxillary palp to an antennae and proboscis, respectively. Previous analysis of the requirements of SCR activity for adult pattern formation has shown that ectopic expression of SCR results in an antenna-to-tarsus transformation, but removal of SCR activity in a clone of cells does not result in a tarsus-to-arista transformation. Here we show in five independent assays the reason for this apparent contradictory requirement of SCR activity in tarsus determination. SCR activity is required cell nonautonomously for tarsus determination. Specifically, we propose that SCR activity is required in the mesodermal adepithelial cells of all leg imaginal discs at late second/early third instar larval stage for the synthesis of a mesoderm-specific, tarsus inducing, signaling factor, which after secretion from the adepithelial cells acts on the overlaying ectodermal cells determining tarsus identity. This study characterizes a combinatorial interaction between two HOX proteins; a mechanism that may have a major role in patterning the anterior-posterior axis of other animals. PMID- 9362476 TI - Kv2.1/Kv9.3, a novel ATP-dependent delayed-rectifier K+ channel in oxygen sensitive pulmonary artery myocytes. AB - The molecular structure of oxygen-sensitive delayed-rectifier K+ channels which are involved in hypoxic pulmonary artery (PA) vasoconstriction has yet to be elucidated. To address this problem, we identified the Shab K+ channel Kv2.1 and a novel Shab-like subunit Kv9.3, in rat PA myocytes. Kv9.3 encodes an electrically silent subunit which associates with Kv2.1 and modulates its biophysical properties. The Kv2.1/9.3 heteromultimer, unlike Kv2.1, opens in the voltage range of the resting membrane potential of PA myocytes. Moreover, we demonstrate that the activity of Kv2.1/Kv9.3 is tightly controlled by internal ATP and is reversibly inhibited by hypoxia. In conclusion, we propose that metabolic regulation of the Kv2.1/Kv9.3 heteromultimer may play an important role in hypoxic PA vasoconstriction and in the possible development of PA hypertension. PMID- 9362477 TI - Converting blood coagulation factor IXa into factor Xa: dramatic increase in amidolytic activity identifies important active site determinants. AB - The coagulation factors IXa (fIXa) and Xa (fXa) share extensive structural and functional homology; both cleave natural substrates effectively only with a cofactor at a phospholipid surface. However, the amidolytic activity of fIXa is 10(4)-fold lower than that of fXa. To identify determinants of this poor reactivity, we expressed variants of truncated fIXa (rf9a) and fXa (rf10a) in Escherichia coli. The crystal structures of fIXa and fXa revealed four characteristic active site components which were subsequently exchanged between rf9a and rf10a. Exchanging Glu219 by Gly or exchanging the 148 loop did not increase activity of rf9a, whereas corresponding mutations abolished reactivity of rf10a. Exchanging Ile213 by Val only moderately increased reactivity of rf9a. Exchanging the 99 loop, however, dramatically increased reactivity. Furthermore, combining all four mutations essentially introduced fXa properties into rf9a: the amidolytic activity was increased 130-fold with fXa substrate selectivity. The results suggest a 2-fold origin of fIXa's poor reactivity. A narrowed S3/S4 subsite disfavours interaction with substrate P3/P4 residues, while a distorted S1 subsite disfavours effective cleavage of the scissile bond. Both defects could be repaired by introducing fXa residues. Such engineered coagulation enzymes will be useful in diagnostics and in the development of therapeutics. PMID- 9362478 TI - Signal peptide fragments of preprolactin and HIV-1 p-gp160 interact with calmodulin. AB - Secretory proteins and most membrane proteins are synthesized with a signal sequence that is usually cleaved from the nascent polypeptide during transport into the lumen of the endoplasmic reticulum. Using site-specific photo crosslinking we have followed the fate of the signal sequence of preprolactin in a cell-free system. This signal sequence has an unusually long hydrophilic n region containing several positively charged amino acid residues. We found that after cleavage by signal peptidase the signal sequence is in contact with lipids and subunits of the signal peptidase complex. The cleaved signal sequence is processed further and an N-terminal fragment is released into the cytosol. This signal peptide fragment was found to interact efficiently with calmodulin. Similar to preprolactin, the signal sequence of the HIV-1 envelope protein p gp160 has the characteristic feature for calmodulin binding in its n-region. We found that a signal peptide fragment of p-gp160 was released into the cytosol and interacts with calmodulin. Our results suggest that signal peptide fragments of some cellular and viral proteins can interact with cytosolic target molecules. The functional consequences of such interactions remain to be established. However, our data suggest that signal sequences may be functionally more versatile than anticipated up to now. PMID- 9362479 TI - The crystal structure of a phosphorylase kinase peptide substrate complex: kinase substrate recognition. AB - The structure of a truncated form of the gamma-subunit of phosphorylase kinase (PHKgammat) has been solved in a ternary complex with a non-hydrolysable ATP analogue (adenylyl imidodiphosphate, AMPPNP) and a heptapeptide substrate related in sequence to both the natural substrate and to the optimal peptide substrate. Kinetic characterization of the phosphotransfer reaction confirms the peptide to be a good substrate, and the structure allows identification of key features responsible for its high affinity. Unexpectedly, the substrate peptide forms a short anti-parallel beta-sheet with the kinase activation segment, the region which in other kinases plays an important role in regulation of enzyme activity. This anchoring of the main chain of the substrate peptide at a fixed distance from the gamma-phosphate of ATP explains the selectivity of PHK for serine/threonine over tyrosine as a substrate. The catalytic core of PHK exists as a dimer in crystals of the ternary complex, and the relevance of this phenomenon to its in vivo recognition of dimeric glycogen phosphorylase b is considered. PMID- 9362480 TI - Solution structure of the transforming growth factor beta-binding protein-like module, a domain associated with matrix fibrils. AB - Here we describe the high resolution nuclear magnetic resonance (NMR) structure of a transforming growth factor beta (TGF-beta)-binding protein-like (TB) domain, which comes from human fibrillin-1, the protein defective in the Marfan syndrome (MFS). This domain is found in fibrillins and latent TGF-beta-binding proteins (LTBPs) which are localized to fibrillar structures in the extracellular matrix. The TB domain manifests a novel fold which is globular and comprises six antiparallel beta-strands and two alpha-helices. An unusual cysteine triplet conserved in the sequences of TB domains is localized to the hydrophobic core, at the C-terminus of an alpha-helix. The structure is stabilized by four disulfide bonds which pair in a 1-3, 2-6, 4-7, 5-8 pattern, two of which are solvent exposed. Analyses of MFS-causing mutations and the fibrillin-1 cell-binding RGD site provide the first clues to the surface specificity of TB domain interactions. Modelling of a homologous TB domain from LTBP-1 (residues 1018 1080) suggests that hydrophobic contacts may play a role in its interaction with the TGF-beta1 latency-associated peptide. PMID- 9362481 TI - Parasite and mammalian GPI biosynthetic pathways can be distinguished using synthetic substrate analogues. AB - Glycosylphosphatidylinositol (GPI) structures are attached to many cell surface glycoproteins in lower and higher eukaryotes. GPI structures are particularly abundant in trypanosomatid parasites where they can be found attached to complex phosphosaccharides, as well as to glycoproteins, and as mature surface glycolipids. The high density of GPI structures at all life-cycle stages of African trypanosomes and Leishmania suggests that the GPI biosynthetic pathway might be a reasonable target for the development of anti-parasite drugs. In this paper we show that synthetic analogues of early GPI intermediates having the 2 hydroxyl group of the D-myo-inositol residue methylated are recognized and mannosylated by the GPI biosynthetic pathways of Trypanosoma brucei and Leishmania major but not by that of human (HeLa) cells. These findings suggest that the discovery and development of specific inhibitors of parasite GPI biosynthesis are attainable goals. Moreover, they demonstrate that inositol acylation is required for mannosylation in the HeLa cell GPI biosynthetic pathway, whereas it is required for ethanolamine phosphate addition in the T.brucei GPI biosynthetic pathway. PMID- 9362482 TI - Domain structure and intramolecular regulation of dynamin GTPase. AB - Dynamin is a 100 kDa GTPase required for receptor-mediated endocytosis, functioning as the key regulator of the late stages of clathrin-coated vesicle budding. It is specifically targeted to clathrin-coated pits where it self assembles into 'collars' required for detachment of coated vesicles from the plasma membrane. Self-assembly stimulates dynamin GTPase activity. Thus, dynamin dynamin interactions are critical in regulating its cellular function. We show by crosslinking and analytical ultracentrifugation that dynamin is a tetramer. Using limited proteolysis, we have defined structural domains of dynamin and evaluated the domain interactions and requirements for self-assembly and GTP binding and hydrolysis. We show that dynamin's C-terminal proline- and arginine-rich domain (PRD) and dynamin's pleckstrin homology (PH) domain are, respectively, positive and negative regulators of self-assembly and GTP hydrolysis. Importantly, we have discovered that the alpha-helical domain interposed between the PH domain and the PRD interacts with the N-terminal GTPase domain to stimulate GTP hydrolysis. We term this region the GTPase effector domain (GED) of dynamin. PMID- 9362483 TI - Several cooperating binding sites mediate the interaction of a lysosomal enzyme with phosphotransferase. AB - Lysosomal targeting of soluble lysosomal hydrolases is mediated by mannose 6 phosphate receptors, which recognize and bind mannose 6-phosphate residues in the oligosaccharide chains of proteins destined for delivery to lysosomes. This recognition marker is generated by the sequential action of two enzymes, the first of which, UDP-N-acetylglucosamine phosphotransferase, recognizes lysosomal enzymes on the basis of a structural determinant in their polypeptide chains. This recognition event is a key step in lysosomal targeting of soluble proteins, but the exact nature of the recognition determinant is not well understood. In this study we have characterized the phosphotransferase recognition signals of human lysosomal aspartylglucosaminidase (AGA) using transient expression of polypeptides carrying targeted amino acid substitutions. We found that three lysine residues and a tyrosine residing in three spatially distinct regions of the AGA polypeptide are necessary for phosphorylation of the oligosaccharides. Two of the lysines are especially important for the lysosomal targeting efficiency of AGA, which seems to be mostly dictated by the degree of phosphorylation of the alpha subunit oligosaccharide. On the basis of the results of this and previous studies we suggest a general model for recognition of lysosomal enzymes by the phosphotransferase. PMID- 9362484 TI - The C-propeptide domain of procollagen can be replaced with a transmembrane domain without affecting trimer formation or collagen triple helix folding during biosynthesis. AB - The folding and assembly of procollagen occurs within the cell through a series of discrete steps leading to the formation of a stable trimer consisting of three distinct domains: the N-propeptide, the C-propeptide and the collagen triple helix flanked at either end by short telopeptides. We have established a semi permeabilized cell system which allows us to study the initial stages in the folding and assembly of procollagen as they would occur in the intact cell. By studying the folding and assembly of the C-propeptide domain in isolation, and a procollagen molecule which lacks the C-propeptide, we have shown that this domain directs the initial association event and is required to allow triple helix formation. However, the essential function of this domain does not include triple helix nucleation or alignment, since this can occur when the C-propeptide is substituted with a single transmembrane domain. Also the telopeptide region is not involved in triple helix nucleation; however, a minimum of two hydroxyproline containing Gly-X-Y triplets at the C-terminal end of the triple helix are required for nucleation to occur. Thus, the C-propeptide is required solely to ensure association of the monomeric chains; once these are brought together, the triple helix is able to nucleate and fold to form a correctly aligned triple helix. PMID- 9362485 TI - Assembly of human prolyl 4-hydroxylase and type III collagen in the yeast pichia pastoris: formation of a stable enzyme tetramer requires coexpression with collagen and assembly of a stable collagen requires coexpression with prolyl 4 hydroxylase. AB - Prolyl 4-hydroxylase, the key enzyme of collagen synthesis, is an alpha2beta2 tetramer, the beta subunit of which is protein disulfide isomerase (PDI). Coexpression of the human alpha subunit and PDI in Pichia produced trace amounts of an active tetramer. A much higher, although still low, assembly level was obtained using a Saccharomyces pre-pro sequence in PDI. Coexpression with human type III procollagen unexpectedly increased the assembly level 10-fold, with no increase in the total amounts of the subunits. The recombinant enzyme was active not only in Pichia extracts but also inside the yeast cell, indicating that Pichia must have a system for transporting all the cosubstrates needed by the enzyme into the lumen of the endoplasmic reticulum. The 4-hydroxyproline containing procollagen polypeptide chains were of full length and formed molecules with stable triple helices even though Pichia probably has no Hsp47 like protein. The data indicate that collagen synthesis in Pichia, and probably also in other cells, involves a highly unusual control mechanism, in that production of a stable prolyl 4-hydroxylase requires collagen expression while assembly of a stable collagen requires enzyme expression. This Pichia system seems ideal for the high-level production of various recombinant collagens for numerous scientific and medical purposes. PMID- 9362486 TI - Disruption of the plastid ycf10 open reading frame affects uptake of inorganic carbon in the chloroplast of Chlamydomonas. AB - The product of the chloroplast ycf10 gene has been localized in the inner chloroplast envelope membrane (Sasaki et al., 1993) and found to display sequence homology with the cyanobacterial CotA product which is altered in mutants defective in CO2 transport and proton extrusion (Katoh et al., 1996a,b). In Chlamydomonas reinhardtii, ycf10, located between the psbI and atpH genes, encodes a putative hydrophobic protein of 500 residues, which is considerably larger than its higher plant homologue because of a long insertion that separates the conserved N and C termini. Using biolistic transformation, we have disrupted ycf10 with the chloroplast aadA expression cassette and examined the phenotype of the homoplasmic transformants. These were found to grow both photoheterotrophically and photoautotrophically under low light, thereby revealing that the Ycf10 product is not essential for the photosynthetic reactions. However, under high light these transformants did not grow photoautotrophically and barely photoheterotrophically. The increased light sensitivity of the transformants appears to result from a limitation in photochemical energy utilization and/or dissipation which correlates with a greatly diminished photosynthetic response to exogenous (CO2 + HCO3-), especially under conditions where the chloroplast inorganic carbon transport system is not induced. Mass spectrometric measurements with either whole cells or isolated chloroplasts from the transformants revealed that the CO2 and HCO3- uptake systems have a reduced affinity for their substrates. The results suggest the existence of a ycf10-dependent system within the plastid envelope which promotes efficient inorganic carbon (Ci) uptake into chloroplasts. PMID- 9362487 TI - Active unfolding of precursor proteins during mitochondrial protein import. AB - Precursor proteins made in the cytoplasm must be in an unfolded conformation during import into mitochondria. Some precursor proteins have tightly folded domains but are imported faster than they unfold spontaneously, implying that mitochondria can unfold proteins. We measured the import rates of artificial precursors containing presequences of varying length fused to either mouse dihydrofolate reductase or bacterial barnase, and found that unfolding of a precursor at the mitochondrial surface is dramatically accelerated when its presequence is long enough to span both membranes and to interact with mhsp70 in the mitochondrial matrix. If the presequence is too short, import is slow but can be strongly accelerated by urea-induced unfolding, suggesting that import of these 'short' precursors is limited by spontaneous unfolding at the mitochondrial surface. With precursors that have sufficiently long presequences, unfolding by the inner membrane import machinery can be orders of magnitude faster than spontaneous unfolding, suggesting that mhsp70 can act as an ATP-driven force generating motor during protein import. PMID- 9362488 TI - Agonists induce conformational changes in transmembrane domains III and VI of the beta2 adrenoceptor. AB - Agonist binding to G protein-coupled receptors is believed to promote a conformational change that leads to the formation of the active receptor state. However, the character of this conformational change which provides the important link between agonist binding and G protein coupling is not known. Here we report evidence that agonist binding to the beta2 adrenoceptor induces a conformational change around 125Cys in transmembrane domain (TM) III and around 285Cys in TM VI. A series of mutant beta2 adrenoceptors with a limited number of cysteines available for chemical derivatization were purified, site-selectively labeled with the conformationally sensitive, cysteine-reactive fluorophore IANBD and analyzed by fluorescence spectroscopy. Like the wild-type receptor, mutant receptors containing 125Cys and/or 285Cys showed an agonist-induced decrease in fluorescence, while no agonist-induced response was observed in a receptor where these two cysteines were mutated. These data suggest that IANBD bound to 125Cys and 285Cys are exposed to a more polar environment upon agonist binding, and indicate that movements of transmembrane segments III and VI are involved in activation of G protein-coupled receptors. PMID- 9362489 TI - Stimulation of gene induction and cell growth by the Ras effector Rlf. AB - Rlf is a ubiquitously expressed distinct relative of RalGDS that interacts with active Ras in vitro. We now demonstrate that Rlf, when co-expressed with Ras mutants, associates in vivo with RasV12 and the effector-domain mutant RasV12G37, but not with RasV12E38 or RasV12C40. Rlf exhibits guanine nucleotide exchange activity towards the small GTPase Ral and, importantly, Rlf-induced Ral activation is stimulated by active Ras. In addition, RasV12 and RasV12G37 synergize with Rlf in the transcriptional activation of the c-fos promoter. Rlf, when targeted to the plasma membrane using the Ras farnesyl attachment site (Rlf CAAX), is constitutively active, inducing both Ral activation and c-fos promoter activity. Rlf-CAAX-induced gene expression is insensitive to dominant negative Ras and the MEK inhibitor PD98059, and involves activation of the serum response element. Furthermore, expression of Rlf-CAAX is sufficient to induce proliferation of NIH 3T3 cells under low-serum conditions. These data demonstrate that Rlf is an effector of Ras which functions as an exchange factor for Ral. Rlf mediates a distinct Ras-induced signalling pathway to gene induction. Finally, a constitutively active form of Rlf can stimulate transcriptional activation and cell growth. PMID- 9362490 TI - The DBP gene is expressed according to a circadian rhythm in the suprachiasmatic nucleus and influences circadian behavior. AB - DBP, a PAR leucine zipper transcription factor, accumulates according to a robust circadian rhythm in liver and several other tissues of mouse and rat. Here we report that DBP mRNA levels also oscillate strongly in the suprachiasmatic nucleus (SCN) of the hypothalamus, believed to harbor the central mammalian pacemaker. However, peak and minimum levels of DBP mRNA are reached about 4 h earlier in the SCN than in liver, suggesting that circadian DBP expression is controlled by different mechanisms in SCN and in peripheral tissues. Mice homozygous for a DBP-null allele display less locomotor activity and free-run with a shorter period than otherwise isogenic wild-type animals. The altered locomotor activity in DBP mutant mice and the highly rhythmic expression of the DBP gene in SCN neurons suggest that DBP is involved in controlling circadian behavior. However, since DBP-/- mice are still rhythmic and since DBP protein is not required for the circadian expression of its own gene, dbp is more likely to be a component of the circadian output pathway than a master gene of the clock. PMID- 9362491 TI - Catalytic activity of the yeast SWI/SNF complex on reconstituted nucleosome arrays. AB - A novel, quantitative nucleosome array assay has been developed that couples the activity of a nucleosome 'remodeling' activity to restriction endonuclease activity. This assay has been used to determine the kinetic parameters of ATP dependent nucleosome disruption by the yeast SWI/SNF complex. Our results support a catalytic mode of action for SWI/SNF in the absence of nucleosome targeting. In this quantitative assay SWI/SNF and ATP lead to a 100-fold increase in nucleosomal DNA accessibility, and initial rate measurements indicate that the complex can remodel one nucleosome every 4.5 min on an 11mer nucleosome array. In contrast to SWI/SNF action on mononucleosomes, we find that the SWI/SNF remodeling reaction on a nucleosome array is a highly reversible process. This result suggests that recovery from SWI/SNF action involves interactions among nucleosomes. The biophysical properties of model nucleosome arrays, coupled with the ease with which homogeneous arrays can be reconstituted and the DNA accessibility analyzed, makes the described array system generally applicable for functional analysis of other nucleosome remodeling enzymes, including histone acetyltransferases. PMID- 9362492 TI - Nuclear import of U snRNPs requires importin beta. AB - Macromolecules that are imported into the nucleus can be divided into classes according to their nuclear import signals. The best characterized class consists of proteins which carry a basic nuclear localization signal (NLS), whose transport requires the importin alpha/beta heterodimer. U snRNP import depends on both the trimethylguanosine cap of the snRNA and a signal formed when the Sm core proteins bind the RNA. Here, factor requirements for U snRNP nuclear import are studied using an in vitro system. Depletion of importin alpha, the importin subunit that binds the NLS, is found to stimulate rather than inhibit U snRNP import. This stimulation is shown to be due to a common requirement for importin beta in both U snRNP and NLS protein import. Saturation of importin beta-mediated transport with the importin beta-binding domain of importin alpha blocks U snRNP import both in vitro and in vivo. Immunodepletion of importin beta inhibits both NLS-mediated and U snRNP import. While the former requires re-addition of both importin alpha and importin beta, re-addition of importin beta alone to immunodepleted extracts was sufficient to restore efficient U snRNP import. Thus importin beta is required for U snRNP import, and it functions in this process without the NLS-specific importin alpha. PMID- 9362493 TI - Alternatively spliced insertions in the paired domain restrict the DNA sequence specificity of Pax6 and Pax8. AB - Transcription factors of the Pax family bind to their target genes via the paired domain which is known to be composed of two subdomains each recognizing distinct half-sites in adjacent major grooves of the DNA helix. We now demonstrate that the mammalian Pax8 gene gives rise, by alternative mRNA splicing, to a protein isoform containing an extra serine residue in the recognition alpha-helix 3 of the paired domain. This Pax8(S) protein does not interact with bipartite paired domain-binding sites, indicating that inactivation of the N-terminal DNA-binding motif severely restricts the sequence specificity of the paired domain. However, the Pax8(S) protein binds in vitro and in vivo to the 5aCON sequence which was previously identified as a high-affinity binding site for the Pax6(5a) splice variant carrying a 14-amino-acid insertion in the paired domain. The 5aCON sequence is shown to consist of four interdigitated 5' half-sites of the bipartite consensus sequence and is thus bound by four Pax8(S) molecules via the intact C-terminal DNA-binding motif of the paired domain. Together these data suggest that inactivation of the N-terminal region of the paired domain by alternative splicing is used in vivo to selectively target Pax transcription factors to gene regulatory regions containing highly specialized 5aCON-like sequences. PMID- 9362494 TI - Both RNA editing and RNA cleavage are required for translation of tobacco chloroplast ndhD mRNA: a possible regulatory mechanism for the expression of a chloroplast operon consisting of functionally unrelated genes. AB - Tobacco chloroplast genes encoding a photosystem I component (psaC) and a NADH dehydrogenase subunit (ndhD) are transcribed as a dicistronic pre-mRNA which is then cleaved into short mRNAs. An RNA protection assay revealed that the cleavage occurs at multiple sites in the intercistronic region. There are two possible initiation codons in the tobacco ndhD mRNA: the upstream AUG and the AUG created by RNA editing from the in-frame ACG located 25 nt downstream. Using the chloroplast in vitro translation system, we found that translation begins only from the edited AUG. The extent of ACG to AUG editing is partial and depends on developmental and environmental conditions. In addition, the in vitro assay showed that the psaC/ndhD dicistronic mRNA is not functional and that the intercistronic cleavage is a prerequisite for both ndhD and psaC translation. Using a series of mutant mRNAs, we showed that an intramolecular interaction between an 8 nt sequence in the psaC coding region and its complementary 8 nt sequence in the 5' ndhD UTR is the negative element for translation of the dicistronic mRNA. A possible mechanism in which the differential expression of the chloroplast operon consists of functionally unrelated genes is discussed. PMID- 9362495 TI - Identification of partners of TIF34, a component of the yeast eIF3 complex, required for cell proliferation and translation initiation. AB - Eukaryotic initiation factor-3 (eIF3) in the yeast Saccharomyces cerevisiae plays a central role in initiation of translation. The eIF3 complex contains at least eight different proteins, but, as yet, little is known about the function of the individual proteins. In this study we have characterized the role of TIF34 (eIF3 p39), a recently identified WD-40 domain-containing protein of 39 kDa, in the eIF3 complex. Using temperature-sensitive mutants of TIF34 we show that this protein is required for cell cycle progression and for mating and plays an essential role in initiation of protein synthesis. By two-hybrid screening we have identified two partners that directly associate with TIF34: PRT1, a previously characterized eIF3 subunit, and a novel protein of 33 kDa (eIF3-p33) which is part of the eIF3 complex and has an RNA binding domain. TIF34 and p33 interact with each other and overexpression of p33 complements the growth defect of a tif34-ts mutant. Our results provide support for both physical and functional interactions between three subunits, TIF34, PRT1 and p33, in the eIF3 complex. PMID- 9362496 TI - Avoiding self: two Tn7-encoded proteins mediate target immunity in Tn7 transposition. AB - The bacterial transposon Tn7 exhibits target immunity, a process that prevents Tn7 from transposing into target DNAs that already contain a copy of the transposon. This work investigates the mechanism of target immunity in vitro. We demonstrate that two Tn7-encoded proteins_TnsB, which binds specifically to the ends of Tn7, and TnsC, the ATP-dependent DNA binding protein_act as a molecular switch to impose immunity on target DNAs containing Tn7 (or just Tn7 ends). TnsC binds to target DNA molecules and communicates with the Tn7 transposition machinery; here we show that target DNAs containing Tn7 ends are also bound and subsequently inactivated by TnsB. Protein-protein interactions between TnsB and TnsC appear to be responsible for this inactivation; the target DNA promotes these interactions by tethering TnsB and TnsC in high local concentration. An attractive model that emerges from this work is that TnsB triggers the dissociation of TnsC from the Tn7 end-containing target DNA; that dissociation depends on TnsC's ability to hydrolyze ATP. We propose that these interactions between TnsB and TnsC not only prevent Tn7 from inserting into itself, but also facilitate the selection of preferred target sites that is the hallmark of Tn7 transposition. PMID- 9362497 TI - Group II intron endonucleases use both RNA and protein subunits for recognition of specific sequences in double-stranded DNA. AB - Group II introns use intron-encoded reverse transcriptase, maturase and DNA endonuclease activities for site-specific insertion into DNA. Remarkably, the endonucleases are ribonucleoprotein complexes in which the excised intron RNA cleaves the sense strand of the recipient DNA by reverse splicing, while the intron-encoded protein cleaves the antisense strand. Here, studies with the yeast group II intron aI2 indicate that both the RNA and protein components of the endonuclease contribute to recognition of an approximately 30 bp DNA target site. Our results lead to a model in which the protein component first recognizes specific nucleotides in the most distal 5' exon region of the DNA target site (E2 21 to -11). Binding of the protein then leads to DNA unwinding, enabling the intron RNA to base pair to a 13 nucleotide DNA sequence (E2-12 to E3+1) for reverse splicing. Antisense-strand cleavage requires additional interactions of the protein with the 3' exon DNA (E3+1 to +10). Our results show how enzymes can use RNA and protein subunits cooperatively to recognize specific sequences in double-stranded DNA. PMID- 9362498 TI - Critical contacts between HIV-1 integrase and viral DNA identified by structure based analysis and photo-crosslinking. AB - Analysis of the crystal structure of HIV-1 integrase reveals a cluster of lysine residues near the active site. Using site-directed mutagenesis and photo crosslinking we find that Lys156 and Lys159 are critical for the functional interaction of integrase with viral DNA. Mutation of Lys156 or Lys159 to glutamate led to a loss of both 3' processing and strand transfer activities in vitro while maintaining the ability to interact with nonspecific DNA and support disintegration. However, mutation of both residues to glutamate produced a synergistic effect eliminating nearly all nonspecific DNA interaction and disintegration activity. In addition, virus containing either of these changes was replication-defective at the step of integration. Photo-crosslinking, using 5 iododeoxyuracil-substituted oligonucleotides, suggests that Lys159 interacts at the N7 position of the conserved deoxyadenosine adjacent to the scissile phosphodiester bond of viral DNA. Sequence conservation throughout retroviral integrases and certain bacterial transposases (e.g. Tn10/IS10) supports the premise that within those families of polynucleotidyl transferases, these residues are strategic for DNA interaction. PMID- 9362499 TI - The transactivation region of the fis protein that controls site-specific DNA inversion contains extended mobile beta-hairpin arms. AB - The Fis protein regulates site-specific DNA inversion catalyzed by a family of DNA invertases when bound to a cis-acting recombinational enhancer. As is often found for transactivation domains, previous crystal structures have failed to resolve the conformation of the N-terminal inversion activation region within the Fis dimer. A new crystal form of a mutant Fis protein now reveals that the activation region contains two beta-hairpin arms that protrude over 20 A from the protein core. Saturation mutagenesis identified the regulatory and structurally important amino acids. The most critical activating residues are located near the tips of the beta-arms. Disulfide cross-linking between the beta-arms demonstrated that they are highly flexible in solution and that efficient inversion activation can occur when the beta-arms are covalently linked together. The emerging picture for this regulatory motif is that contacts with the recombinase at the tip of the mobile beta-arms activate the DNA invertase in the context of an invertasome complex. PMID- 9362500 TI - Double-strand break repair by Ku70 requires heterodimerization with Ku80 and DNA binding functions. AB - Heterodimers of the 70 and 80 kDa Ku autoantigens (Ku70 and Ku80) activate the DNA-dependent protein kinase (DNA-PK). Mutations in any of the three subunits of this protein kinase (Ku70, Ku80 and DNA-PKcs) lead to sensitivity to ionizing radiation (IR) and to DNA double-strand breaks, and V(D)J recombination product formation defects. Here we show that the IR repair, DNA end binding and DNA-PK defects in Ku70-/- embryonic stem cells can be counteracted by introducing epitope-tagged wild-type Ku70 cDNA. Truncations and chimeras of Ku70 were used to identify the regions necessary for DNA end binding and IR repair. Site-specific mutational analysis revealed a core region of Ku70 responsible for DNA end binding and heterodimerization. The propensity for Ku70 to associate with Ku80 and to bind DNA correlates with the ability to activate DNA-PK, although two mutants showed that the roles of Ku70 in DNA-PK activation and IR repair are separate. Mutation of DNA-PK autophosphorylation sites and other structural motifs in Ku70 showed that these sites are not necessary for IR repair in vivo. These studies reveal Ku70 features required for double-strand break repair. PMID- 9362501 TI - The phiX174-type primosome promotes replisome assembly at the site of recombination in bacteriophage Mu transposition. AB - Initiation of Escherichia coli DNA synthesis primed by homologous recombination is believed to require the phiX174-type primosome, a mobile priming apparatus assembled without the initiator protein DnaA. We show that this primosome plays an essential role in bacteriophage Mu DNA replication by transposition. Upon promoting transfer of Mu ends to target DNA, the Mu transpososome undergoes transition to a pre-replisome that permits initiation of DNA synthesis only in the presence of primosome assembly proteins PriA, DnaT, DnaB and DnaC. These assembly proteins promote the engagement of primase and DNA polymerase III holoenzyme, initiating semi-discontinuous replication preferentially at the Mu left end. The results indicate that these proteins play a crucial role in promoting replisome assembly on a recombination intermediate. PMID- 9362502 TI - Neocentromere-mediated chromosome movement in maize. AB - Neocentromere activity is a classic example of nonkinetochore chromosome movement. In maize, neocentromeres are induced by a gene or genes on Abnormal chromosome 10 (Ab10) which causes heterochromatic knobs to move poleward at meiotic anaphase. Here we describe experiments that test how neocentromere activity affects the function of linked centromere/kinetochores (kinetochores) and whether neocentromeres and kinetochores are mobilized on the spindle by the same mechanism. Using a newly developed system for observing meiotic chromosome congression and segregation in living maize cells, we show that neocentromeres are active from prometaphase through anaphase. During mid-anaphase, normal chromosomes move on the spindle at an average rate of 0.79 micron/min. The presence of Ab10 does not affect the rate of normal chromosome movement but propels neocentromeres poleward at rates as high as 1.4 micron/min. Kinetochore mediated chromosome movement is only marginally affected by the activity of a linked neocentromere. Combined in situ hybridization/immunocytochemistry is used to demonstrate that unlike kinetochores, neocentromeres associate laterally with microtubules and that neocentromere movement is correlated with knob size. These data suggest that microtubule depolymerization is not required for neocentromere motility. We argue that neocentromeres are mobilized on microtubules by the activity of minus end-directed motor proteins that interact either directly or indirectly with knob DNA sequences. PMID- 9362503 TI - Ran-unassisted nuclear migration of a 97-kD component of nuclear pore-targeting complex. AB - A 97-kD component of nuclear pore-targeting complex (the beta-subunit of nuclear pore-targeting complex [PTAC]/importin/karyopherin) mediates the import of nuclear localization signal (NLS)-containing proteins by anchoring the NLS receptor protein (the alpha-subunit of PTAC/importin/karyopherin) to the nuclear pore complex (NPC). The import requires a small GTPase Ran, which interacts directly with the beta-subunit. The present study describes an examination of the behavior of the beta-subunit in living cells and in digitonin-permeabilized cells. In living cells, cytoplasmically injected beta-subunit rapidly migrates into the nucleus. The use of deletion mutants reveals that nuclear migration of the beta-subunit requires neither Ran- nor alpha-subunit-binding but only the NPC binding domain of this molecule, which is also involved in NLS-mediated import. Furthermore, unlike NLS-mediated import, a dominant-negative Ran, defective in GTP-hydrolysis, did not inhibit nuclear migration of the beta-subunit. In the digitonin-permeabilized cell-free import assay, the beta-subunit transits rapidly through the NPC into the nucleus in a saturating manner in the absence of exogenous addition of soluble factors. These results show that the beta-subunit undergoes translocation at the NPC in a Ran-unassisted manner when it does not carry alpha-subunit/NLS substrate. Therefore, a requirement for Ran arises only when the beta-subunit undergoes a translocation reaction together with the alpha subunit/NLS substrate. The results provide an insight to the yet unsolved question regarding the mechanism by which proteins are directionally transported through the NPC, and the role of Ran in this process. PMID- 9362504 TI - Glypican and biglycan in the nuclei of neurons and glioma cells: presence of functional nuclear localization signals and dynamic changes in glypican during the cell cycle. AB - We have investigated the expression patterns and subcellular localization in nervous tissue of glypican, a major glycosylphosphatidylinositol-anchored heparan sulfate proteoglycan that is predominantly synthesized by neurons, and of biglycan, a small, leucine-rich chondroitin sulfate proteoglycan. By laser scanning confocal microscopy of rat central nervous tissue and C6 glioma cells, we found that a significant portion of the glypican and biglycan immunoreactivity colocalized with nuclear staining by propidium iodide and was also seen in isolated nuclei. In certain regions, staining was selective, insofar as glypican and biglycan immunoreactivity in the nucleus was seen predominantly in a subpopulation of large spinal cord neurons. The amino acid sequences of both proteoglycans contain potential nuclear localization signals, and these were demonstrated to be functional based on their ability to target beta-galactosidase fusion proteins to the nuclei of transfected 293 cells. Nuclear localization of glypican beta-galactosidase or Fc fusion proteins in transfected 293 cells and C6 glioma cells was greatly reduced or abolished after mutation of the basic amino acids or deletion of the sequence containing the nuclear localization signal, and no nuclear staining was seen in the case of heparan sulfate and chondroitin sulfate proteoglycans that do not possess a nuclear localization signal, such as syndecan-3 or decorin (which is closely related in structure to biglycan). Transfection of COS-1 cells with an epitope-tagged glypican cDNA demonstrated transport of the full-length proteoglycan to the nucleus, and there are also dynamic changes in the pattern of glypican immunoreactivity in the nucleus of C6 cells both during cell division and correlated with different phases of the cell cycle. Our data therefore suggest that in certain cells and central nervous system regions, glypican and biglycan may be involved in the regulation of cell division and survival by directly participating in nuclear processes. PMID- 9362505 TI - The testicular antiviral defense system: localization, expression, and regulation of 2'5' oligoadenylate synthetase, double-stranded RNA-activated protein kinase, and Mx proteins in the rat seminiferous tubule. AB - Although the involvement of viruses in alterations of testicular function and in sexually transmitted diseases is well known, paradoxically, the testicular antiviral defense system has virtually not been studied. The well known antiviral activity of interferons (IFNs) occurs via the action of several IFN-induced proteins, among which the 2'5' oligoadenylate synthetase (2'5' A synthetase), the double-stranded RNA-activated protein kinase (PKR), and the Mx proteins are the best known. To explore the antiviral capacity of the testis and to study the testicular action of IFNs, we looked for the presence and regulation of these three proteins in isolated seminiferous tubule cells, cultured in the presence or in the absence of IFN alpha, IFN gamma, or Sendai virus. In all conditions tested, the meiotic pachytene spermatocytes and the post-meiotic early spermatids lacked 2'5' A synthetase, PKR, and Mx mRNAs and proteins. In contrast, Sertoli cells constitutively expressed these mRNAs and proteins, and their levels were greatly increased after IFN alpha or Sendai virus exposure. While peritubular cells were also able to markedly express 2'5' A synthetase, PKR, and Mx mRNA and proteins after IFN alpha or viral exposure, only PKR was constitutively present in these cells. Interestingly, IFN gamma had no effect on peritubular cells' 2'5' A synthetase and Mx production but it enhanced Mx proteins in Sertoli cells. In conclusion, this study reveals that the seminiferous tubules are particularly well equipped to react to a virus attack. The fact that the two key tubular elements of the blood-testis barrier, namely, Sertoli and peritubular cells, were found to assume this protection allows the extension of the concept of blood testis barrier to the testicular antiviral defense. PMID- 9362506 TI - Stimulation of NSF ATPase activity by alpha-SNAP is required for SNARE complex disassembly and exocytosis. AB - N-ethylmaleimide-sensitive fusion protein (NSF) and alpha-SNAP play key roles in vesicular traffic through the secretory pathway. In this study, NH2- and COOH terminal truncation mutants of alpha-SNAP were assayed for ability to bind NSF and stimulate its ATPase activity. Deletion of up to 160 NH2-terminal amino acids had little effect on the ability of alpha-SNAP to stimulate the ATPase activity of NSF. However, deletion of as few as 10 COOH-terminal amino acids resulted in a marked decrease. Both NH2-terminal (1-160) and COOH-terminal (160-295) fragments of alpha-SNAP were able to bind to NSF, suggesting that alpha-SNAP contains distinct NH2- and COOH-terminal binding sites for NSF. Sequence alignment of known SNAPs revealed only leucine 294 to be conserved in the final 10 amino acids of alpha-SNAP. Mutation of leucine 294 to alanine (alpha-SNAP(L294A)) resulted in a decrease in the ability to stimulate NSF ATPase activity but had no effect on the ability of this mutant to bind NSF. alpha-SNAP (1-285) and alpha-SNAP (L294A) were unable to stimulate Ca2+-dependent exocytosis in permeabilized chromaffin cells. In addition, alpha-SNAP (1-285), and alpha-SNAP (L294A) were able to inhibit the stimulation of exocytosis by exogenous alpha-SNAP. alpha-SNAP, alpha SNAP (1-285), and alpha-SNAP (L294A) were all able to become incorporated into a 20S complex and recruit NSF. In the presence of MgATP, alpha-SNAP (1-285) and alpha-SNAP (L294A) were unable to fully disassemble the 20S complex and did not allow vesicle-associated membrane protein dissociation to any greater level than seen in control incubations. These findings imply that alpha-SNAP stimulation of NSF ATPase activity may be required for 20S complex disassembly and for the alpha SNAP stimulation of exocytosis. PMID- 9362507 TI - Multiple forms of endocytosis in bovine adrenal chromaffin cells. AB - We studied endocytosis in chromaffin cells with both perforated patch and whole cell configurations of the patch clamp technique using cell capacitance measurements in combination with amperometric catecholamine detection. We found that chromaffin cells exhibit two relatively rapid, kinetically distinct forms of stimulus-coupled endocytosis. A more prevalent "compensatory" retrieval occurs reproducibly after stimulation, recovering an approximately equivalent amount of membrane as added through the immediately preceding exocytosis. Membrane is retrieved through compensatory endocytosis at an initial rate of approximately 6 fF/s. Compensatory endocytotic activity vanishes within a few minutes in the whole cell configuration. A second form of triggered membrane retrieval, termed "excess" retrieval, occurs only above a certain stimulus threshold and proceeds at a faster initial rate of approximately 248 fF/s. It typically undershoots the capacitance value preceding the stimulus, and its magnitude has no clear relationship to the amount of membrane added through the immediately preceding exocytotic event. Excess endocytotic activity persists in the whole cell configuration. Thus, two kinetically distinct forms of endocytosis coexist in intact cells during perforated patch recording. Both are fast enough to retrieve membrane after exocytosis within a few seconds. We argue that the slower one, termed compensatory endocytosis, exhibits properties that make it the most likely mechanism for membrane recycling during normal secretory activity. PMID- 9362508 TI - Functional expression cloning and characterization of SFT, a stimulator of Fe transport. AB - A stimulator of Fe transport (SFT) was identified by functional expression cloning in Xenopus oocytes. SFT-mediated transport has properties defined for transferrin-independent Fe uptake, but its cytolocalization in recycling endosomes and the observed stimulation of transferrin-bound Fe assimilation indicate a key role in intracellular Fe membrane transport as well. SFT has six predicted transmembranous domains and a functionally important RExxE motif that resembles domains involved in yeast Fe transport and Fe-binding by ferritin L chains. The observation that SFT oligomerizes, along with other structural and mechanistic features, suggests it may be a member of either the ATP-binding cassette or cation diffusion facilitator families. The 3' untranslated region of SFT contains a translation inhibitory element and inhibition of SFT expression in Xenopus oocytes was found to be relieved by coinjection of transcripts from other defined cDNAs that are also described in this report. SFT is the first component of the mammalian Fe membrane transport machinery to be identified. PMID- 9362509 TI - Differential localization of vesicular acetylcholine and monoamine transporters in PC12 cells but not CHO cells. AB - Previous studies have indicated that neuro-endocrine cells store monoamines and acetylcholine (ACh) in different secretory vesicles, suggesting that the transport proteins responsible for packaging these neurotransmitters sort to distinct vesicular compartments. Molecular cloning has recently demonstrated that the vesicular transporters for monoamines and ACh show strong sequence similarity, and studies of the vesicular monoamine transporters (VMATs) indicate preferential localization to large dense core vesicles (LDCVs) rather than synaptic-like microvesicles (SLMVs) in rat pheochromocytoma PC12 cells. We now report the localization of the closely related vesicular ACh transporter (VAChT). In PC12 cells, VAChT differs from the VMATs by immunofluorescence and fractionates almost exclusively to SLMVs and endosomes by equilibrium sedimentation. Immunoisolation further demonstrates colocalization with synaptophysin on SLMVs as well as other compartments. However, small amounts of VAChT also occur on LDCVs. Thus, VAChT differs in localization from the VMATs, which sort predominantly to LDCVs. In addition, we demonstrate ACh transport activity in stable PC12 transformants overexpressing VAChT. Since previous work has suggested that VAChT expression confers little if any transport activity in non-neural cells, we also determined its localization in transfected CHO fibroblasts. In CHO cells, VAChT localizes to the same endosomal compartment as the VMATs by immunofluorescence, density gradient fractionation, and immunoisolation with an antibody to the transferrin receptor. We have also detected ACh transport activity in the transfected CHO cells, indicating that localization to SLMVs is not required for function. In summary, VAChT differs in localization from the VMATs in PC12 cells but not CHO cells. PMID- 9362510 TI - Targeting of the synaptic vesicle protein synaptobrevin in the axon of cultured hippocampal neurons: evidence for two distinct sorting steps. AB - Synaptic vesicles are concentrated in the distal axon, far from the site of protein synthesis. Integral membrane proteins destined for this organelle must therefore make complex targeting decisions. Short amino acid sequences have been shown to act as targeting signals directing proteins to a variety of intracellular locations. To identify synaptic vesicle targeting sequences and to follow the path that proteins travel en route to the synaptic vesicle, we have used a defective herpes virus amplicon expression system to study the targeting of a synaptobrevin-transferrin receptor (SB-TfR) chimera in cultured hippocampal neurons. Addition of the cytoplasmic domain of synaptobrevin onto human transferrin receptor was sufficient to retarget the transferrin receptor from the dendrites to presynaptic sites in the axon. At the synapse, the SB-TfR chimera did not localize to synaptic vesicles, but was instead found in an organelle with biochemical and functional characteristics of an endosome. The chimera recycled in parallel with synaptic vesicle proteins demonstrating that the nerve terminal efficiently sorts transmembrane proteins into different pathways. The synaptobrevin sequence that controls targeting to the presynaptic endosome was not localized to a single, 10- amino acid region of the molecule, indicating that this targeting signal may be encoded by a more distributed structural conformation. However, the chimera could be shifted to synaptic vesicles by deletion of amino acids 61-70 in synaptobrevin, suggesting that separate signals encode the localization of synaptobrevin to the synapse and to the synaptic vesicle. PMID- 9362511 TI - The O-glycosylated stalk domain is required for apical sorting of neurotrophin receptors in polarized MDCK cells. AB - Delivery of newly synthesized membrane-spanning proteins to the apical plasma membrane domain of polarized MDCK epithelial cells is dependent on yet unidentified sorting signals present in the luminal domains of these proteins. In this report we show that structural information for apical sorting of transmembrane neurotrophin receptors (p75(NTR)) is localized to a juxtamembrane region of the extracellular domain that is rich in O-glycosylated serine/threonine residues. An internal deletion of 50 amino acids that removes this stalk domain from p75(NTR) causes the protein to be sorted exclusively of the basolateral plasma membrane. Basolateral sorting stalk-minus p75(NTR) does not occur by default, but requires sequences present in the cytoplasmic domain. The stalk domain is also required for apical secretion of a soluble form of p75(NTR), providing the first demonstration that the same domain can mediate apical sorting of both a membrane-anchored as well as secreted protein. However, the single N-glycan present on p75(NTR) is not required for apical sorting of either transmembrane or secreted forms. PMID- 9362512 TI - The effect of apical and basolateral lipids on the function of the band 3 anion exchange protein. AB - Although many polarized proteins are sorted to the same membrane domain in all epithelial tissues, there are some that exhibit a cell type-specific polarity. We recently found that band 3 (the anion exchanger AE1) was present in the apical membrane of a renal intercalated cell line when these cells were seeded at low density, but its targeting was reversed to the basolateral membrane under the influence of an extracellular matrix protein secreted when the cells were seeded at high density. Because apical and basolateral lipids differ in epithelia, we asked what effect might these lipids have on band 3 function. This question is especially interesting since apical anion exchange in these cells is resistant to disulfonic stilbene inhibitors while basolateral anion exchange is quite sensitive. Furthermore, the apical anion exchanger cannot be stained by antibodies that readily identify the basolateral protein. We used short chain sphingolipid analogues and found that sphingomyelin was preferentially targeted to the basolateral domain in the intercalated cell line. The ganglioside GM1 (Gal 1beta1, 3GalNAcbeta1, 4Gal-NeuAcalpha2, 3Galbeta1, 4Glc ceramide) was confined to the apical membrane as visualized by confocal microscopy after addition of fluorescent cholera toxin to filter grown cells. We reconstituted erythrocyte band 3 into liposomes using apical and basolateral types of lipids and examined the inhibitory potency of 4, 4'-dinitorsostilbene-2,2'-disulfonic acid (DNDS; a reversible stilbene) on 35SO4/SO4 exchange. Although anion exchange in sphingomyelin liposomes was sensitive to inhibition, the addition of increasing amounts of the ganglioside GM1 reduced the potency of the inhibitor drastically. Because these polarized lipids are present in the exofacial surface of the bilayer, we propose that the lipid structure might influence the packing of the transmembrane domains of band 3 in that region, altering the binding of the stilbenes to these chains. These results highlight the role of polarized lipids in changing the function of unpolarized proteins or of proteins whose locations differ in different epithelia. PMID- 9362513 TI - Neurabin: a novel neural tissue-specific actin filament-binding protein involved in neurite formation. AB - We purified from rat brain a novel actin filament (F-actin)-binding protein of approximately 180 kD (p180), which was specifically expressed in neural tissue. We named p180 neurabin (neural tissue-specific F-actin- binding protein). We moreover cloned the cDNA of neurabin from a rat brain cDNA library and characterized native and recombinant proteins. Neurabin was a protein of 1,095 amino acids with a calculated molecular mass of 122,729. Neurabin had one F-actin binding domain at the NH2-terminal region, one PSD-95, DlgA, ZO-1-like domain at the middle region, a domain known to interact with transmembrane proteins, and domains predicted to form coiled-coil structures at the COOH-terminal region. Neurabin bound along the sides of F-actin and showed F-actin-cross-linking activity. Immunofluorescence microscopic analysis revealed that neurabin was highly concentrated in the synapse of the developed neurons. Neurabin was also concentrated in the lamellipodia of the growth cone during the development of neurons. Moreover, a study on suppression of endogenous neurabin in primary cultured rat hippocampal neurons by treatment with an antisense oligonucleotide showed that neurabin was involved in the neurite formation. Neurabin is a candidate for key molecules in the synapse formation and function. PMID- 9362514 TI - Microtubule stabilization in pressure overload cardiac hypertrophy. AB - Increased microtubule density, for which microtubule stabilization is one potential mechanism, causes contractile dysfunction in cardiac hypertrophy. After microtubule assembly, alpha-tubulin undergoes two, likely sequential, time dependent posttranslational changes: reversible carboxy-terminal detyrosination (Tyr-tubulin left and right arrow Glu-tubulin) and then irreversible deglutamination (Glu-tubulin --> Delta2-tubulin), such that Glu- and Delta2 tubulin are markers for long-lived, stable microtubules. Therefore, we generated antibodies for Tyr-, Glu-, and Delta2-tubulin and used them for staining of right and left ventricular cardiocytes from control cats and cats with right ventricular hypertrophy. Tyr- tubulin microtubule staining was equal in right and left ventricular cardiocytes of control cats, but Glu-tubulin and Delta2-tubulin staining were insignificant, i.e., the microtubules were labile. However, Glu- and Delta2-tubulin were conspicuous in microtubules of right ventricular cardiocytes from pressure overloaded cats, i.e., the microtubules were stable. This finding was confirmed in terms of increased microtubule drug and cold stability in the hypertrophied cells. In further studies, we found an increase in a microtubule binding protein, microtubule-associated protein 4, on both mRNA and protein levels in pressure-hypertrophied myocardium. Thus, microtubule stabilization, likely facilitated by binding of a microtubule-associated protein, may be a mechanism for the increased microtubule density characteristic of pressure overload cardiac hypertrophy. PMID- 9362516 TI - Astral microtubule dynamics in yeast: a microtubule-based searching mechanism for spindle orientation and nuclear migration into the bud. AB - Localization of dynein-green fluorescent protein (GFP) to cytoplasmic microtubules allowed us to obtain one of the first views of the dynamic properties of astral microtubules in live budding yeast. Several novel aspects of microtubule function were revealed by time-lapse, three-dimensional fluorescence microscopy. Astral microtubules, about four to six in number for each pole, exhibited asynchronous dynamic instability throughout the cell cycle, growing at approximately 0.3-1.5 micron/min toward the cell surface then switching to shortening at similar velocities back to the spindle pole body (SPB). During interphase, a conical array of microtubules trailed the SPB as the nucleus traversed the cytoplasm. Microtubule disassembly by nocodozole inhibited these movements, indicating that the nucleus was pushed around the interior of the cell via dynamic astral microtubules. These forays were evident in unbudded G1 cells, as well as in late telophase cells after spindle disassembly. Nuclear movement and orientation to the bud neck in S/G2 or G2/M was dependent on dynamic astral microtubules growing into the bud. The SPB and nucleus were then pulled toward the bud neck, and further microtubule growth from that SPB was mainly oriented toward the bud. After SPB separation and central spindle formation, a temporal delay in the acquisition of cytoplasmic dynein at one of the spindle poles was evident. Stable microtubule interactions with the cell cortex were rarely observed during anaphase, and did not appear to contribute significantly to spindle alignment or elongation into the bud. Alterations of microtubule dynamics, as observed in cells overexpressing dynein-GFP, resulted in eventual spindle misalignment. These studies provide the first mechanistic basis for understanding how spindle orientation and nuclear positioning are established and are indicative of a microtubule-based searching mechanism that requires dynamic microtubules for nuclear migration into the bud. PMID- 9362515 TI - XMAP310: a Xenopus rescue-promoting factor localized to the mitotic spindle. AB - To understand the role of microtubule-associated proteins (MAPs) in the regulation of microtubule (MT) dynamics we have characterized MAPs prepared from Xenopus laevis eggs (Andersen, S.S.L., B. Buendia, J.E. Dominguez, A. Sawyer, and E. Karsenti. 1994. J. Cell Biol. 127:1289-1299). Here we report on the purification and characterization of a 310-kD MAP (XMAP310) that localizes to the nucleus in interphase and to mitotic spindle MTs in mitosis. XMAP310 is present in eggs, oocytes, a Xenopus tissue culture cell line, testis, and brain. We have purified XMAP310 to homogeneity from egg extracts. The purified protein cross links pure MTs. Analysis of the effect of this protein on MT dynamics by time lapse video microscopy has shown that it increases the rescue frequency 5-10-fold and decreases the shrinkage rate twofold. It has no effect on the growth rate or the catastrophe frequency. Microsequencing data suggest that XMAP230 and XMAP310 are novel MAPs. Although the three Xenopus MAPs characterized so far, XMAP215 (Vasquez, R.J., D.L. Gard, and L. Cassimeris. 1994. J. Cell Biol. 127:985-993), XMAP230, and XMAP310 are localized to the mitotic spindle, they have distinct effects on MT dynamics. While XMAP215 promotes rapid MT growth, XMAP230 decreases the catastrophe frequency and XMAP310 increases the rescue frequency. This may have important implications for the regulation of MT dynamics during spindle morphogenesis and chromosome segregation. PMID- 9362517 TI - Constitutive proteolysis of the ErbB-4 receptor tyrosine kinase by a unique, sequential mechanism. AB - The heregulin receptor tyrosine kinase ErbB-4 is constitutively cleaved, in the presence or absence of ligand, by an exofacial proteolytic activity producing a membrane-anchored cytoplasmic domain fragment of 80 kD. Based on selective sensitivity to inhibitors, the proteolytic activity is identified as that of a metalloprotease. The 80-kD product is tyrosine phosphorylated and retains tyrosine kinase activity. Importantly, the levels of this fragment are controlled by proteasome function. When proteasome activity is inhibited for 6 h, the kinase active 80-kD ErbB-4 fragment accumulates to a level equivalent to 60% of the initial amount of native ErbB-4 (approximately 10(6) receptors per cell). Hence, proteasome activity is essential to prevent the accumulation of a significant level of ligand-independent, active ErbB-4 tyrosine kinase generated by metalloprotease activity. Proteasome activity, however, does not act on the native ErbB-4 receptor before the metalloprotease-mediated cleavage, as no ErbB-4 fragments accumulate when metalloprotease activity is blocked. Although no ubiquitination of the native ErbB-4 is detected, the 80-kD fragment is polyubiquitinated. The data, therefore, describe a unique pathway for the processing of growth factor receptors, which involves the sequential function of an exofacial metalloprotease and the cytoplasmic proteasome. PMID- 9362518 TI - Fas induces cytoplasmic apoptotic responses and activation of the MKK7-JNK/SAPK and MKK6-p38 pathways independent of CPP32-like proteases. AB - IL-1beta converting enzyme (ICE) family cysteine proteases are subdivided into three groups; ICE-, CPP32-, and Ich-1-like proteases. In Fas-induced apoptosis, activation of ICE-like proteases is followed by activation of CPP32-like proteases which is thought to be essential for execution of the cell death. It was recently reported that two subfamily members of the mitogen-activated protein kinase superfamily, JNK/SAPK and p38, are activated during Fas-induced apoptosis. Here, we have shown that MKK7, but not SEK1/ MKK4, is activated by Fas as an activator for JNK/ SAPK and that MKK6 is a major activator for p38 in Fas signaling. Then, to dissect various cellular responses induced by Fas, we used several peptide inhibitors for ICE family proteases in Fas-treated Jurkat cells and KB cells. While Z-VAD-FK which inhibited almost all the Fas-induced cellular responses blocked the activation of JNK/SAPK and p38, Ac-DEVD-CHO and Z-DEVD-FK, specific inhibitors for CPP32-like proteases, which inhibited the Fas-induced chromatin condensation and DNA fragmentation did not block the activation of JNK/SAPK and p38. Interestingly, these DEVD-type inhibitors did not block the Fas induced morphological changes (cell shrinkage and surface blebbing), induction of Apo2.7 antigen, or the cell death (as assessed by the dye exclusion ability). These results suggest that the Fas-induced activation of the JNK/SAPK and p38 signaling pathways does not require CPP32-like proteases and that CPP32-like proteases, although essential for apoptotic nuclear events (such as chromatin condensation and DNA fragmentation), are not required for other apoptotic events in the cytoplasm or the cell death itself. Thus, the Fas signaling pathway diverges into multiple, separate processes, each of which may be responsible for part of the apoptotic cellular responses. PMID- 9362519 TI - Lack of correlation between activation of Jun-NH2-terminal kinase and induction of apoptosis after detachment of epithelial cells. AB - Detachment of epithelial cells from the extracellular matrix leads to induction of programmed cell death, a process that has been termed "anoikis." It has been reported recently that detachment of MDCK cells from matrix results in activation of Jun-NH2-terminal kinases (JNKs) and speculated that these stress activated protein kinases play a causal role in the induction of anoikis (Frisch, S.M., K. Vuori, D. Kelaita, and S. Sicks. 1996. J. Cell Biol. 135:1377-1382). We report here that although JNK is activated by detachment of normal MDCK cells, study of cell lines expressing activated signaling proteins usually controlled by Ras shows that stimulation of JNK fails to correlate with induction of anoikis. Activated phosphoinositide 3-OH kinase and activated PKB/Akt protect MDCK cells from detachment-induced apoptosis without suppressing JNK activation. Conversely, activated Raf and dominant negative SEK1, a JNK kinase, attenuate detachment induced JNK activation without protecting from apoptosis. zVAD-fmk, a peptide inhibitor of caspases, prevents MDCK cell anoikis without affecting JNK activation. p38, a related stress-activated kinase, is also stimulated by detachment from matrix, but inhibition of this kinase with SB 203580 does not protect from anoikis. It is therefore unlikely that either JNK or p38 play a direct role in detachment-induced programmed cell death in epithelial cells. PMID- 9362520 TI - Precocious mammary gland development in P-cadherin-deficient mice. AB - To investigate the functions of P-cadherin in vivo, we have mutated the gene encoding this cell adhesion receptor in mice. In contrast to E- and N-cadherin- deficient mice, mice homozygous for the P-cadherin mutation are viable. Although P-cadherin is expressed at high levels in the placenta, P-cadherin-null females are fertile. P-cadherin expression is localized to the myoepithelial cells surrounding the lumenal epithelial cells of the mammary gland. The role of the myoepithelium as a contractile tissue necessary for milk secretion is clear, but its function in the nonpregnant animal is unknown. The ability of the P-cadherin mutant female to nurse and maintain her litter indicates that the contractile function of the myoepithelium is not dependent on the cell adhesion molecule P cadherin. The virgin P-cadherin-null females display precocious differentiation of the mammary gland. The alveolar-like buds in virgins resemble the glands of an early pregnant animal morphologically and biochemically (i.e., milk protein synthesis). The P-cadherin mutant mice develop hyperplasia and dysplasia of the mammary epithelium with age. In addition, abnormal lymphocyte infiltration was observed in the mammary glands of the mutant animals. These results indicate that P-cadherin-mediated adhesion and/or signals derived from cell-cell interactions are important determinants in negative growth control in the mammary gland. Furthermore, the loss of P-cadherin from the myoepithelium has uncovered a novel function for this tissue in maintaining the undifferentiated state of the underlying secretory epithelium. PMID- 9362521 TI - Antagonism of cell adhesion by an alpha-catenin mutant, and of the Wnt-signaling pathway by alpha-catenin in Xenopus embryos. AB - In Xenopus laevis development, beta-catenin plays an important role in the Wnt signaling pathway by establishing the Nieuwkoop center, which in turn leads to specification of the dorsoventral axis. Cadherins are essential for embryonic morphogenesis since they mediate calcium-dependent cell-cell adhesion and can modulate beta-catenin signaling. alpha-catenin links beta-catenin to the actin based cytoskeleton. To study the role of endogenous alpha-catenin in early development, we have made deletion mutants of alphaN-catenin. The binding domain of beta-catenin has been mapped to the NH2-terminal 210 amino acids of alphaN catenin. Overexpression of mutants lacking the COOH-terminal 230 amino acids causes severe developmental defects that reflect impaired calcium-dependent blastomere adhesion. Lack of normal adhesive interactions results in a loss of the blastocoel in early embryos and ripping of the ectodermal layer during gastrulation. The phenotypes of the dominant-negative mutants can be rescued by coexpressing full-length alphaN-catenin or a mutant of beta-catenin that lacks the internal armadillo repeats. We next show that coexpression of alphaN-catenin antagonizes the dorsalizing effects of beta-catenin and Xwnt-8. This can be seen phenotypically, or by studying the effects of expression on the downstream homeobox gene Siamois. Thus, alpha-catenin is essential for proper morphogenesis of the embryo and may act as a regulator of the intracellular beta-catenin signaling pathway in vivo. PMID- 9362522 TI - Regulation of cell-cell adhesion by rac and rho small G proteins in MDCK cells. AB - The Rho small G protein family, consisting of the Rho, Rac, and Cdc42 subfamilies, regulates various cell functions, such as cell shape change, cell motility, and cytokinesis, through reorganization of the actin cytoskeleton. We show here that the Rac and Rho subfamilies furthermore regulate cell-cell adhesion. We prepared MDCK cell lines stably expressing each of dominant active mutants of RhoA (sMDCK-RhoDA), Rac1 (sMDCK-RacDA), and Cdc42 (sMDCK-Cdc42DA) and dominant negative mutants of Rac1 (sMDCK-RacDN) and Cdc42 (sMDCK-Cdc42DN) and analyzed cell adhesion in these cell lines. The actin filaments at the cell-cell adhesion sites markedly increased in sMDCK-RacDA cells, whereas they apparently decreased in sMDCK-RacDN cells, compared with those in wild-type MDCK cells. Both E-cadherin and beta-catenin, adherens junctional proteins, at the cell-cell adhesion sites also increased in sMDCK-RacDA cells, whereas both of them decreased in sMDCK-RacDN cells. The detergent solubility assay indicated that the amount of detergent-insoluble E-cadherin increased in sMDCK-RacDA cells, whereas it slightly decreased in sMDCK-RacDN cells, compared with that in wild-type MDCK cells. In sMDCK-RhoDA, -Cdc42DA, and -Cdc42DN cells, neither of these proteins at the cell-cell adhesion sites was apparently affected. ZO-1, a tight junctional protein, was not apparently affected in any of the transformant cell lines. Electron microscopic analysis revealed that sMDCK-RacDA cells tightly made contact with each other throughout the lateral membranes, whereas wild-type MDCK and sMDCK-RacDN cells tightly and linearly made contact at the apical area of the lateral membranes. These results suggest that the Rac subfamily regulates the formation of the cadherin-based cell- cell adhesion. Microinjection of C3 into wild-type MDCK cells inhibited the formation of both the cadherin-based cell-cell adhesion and the tight junction, but microinjection of C3 into sMDCK-RacDA cells showed little effect on the localization of the actin filaments and E-cadherin at the cell-cell adhesion sites. These results suggest that the Rho subfamily is necessary for the formation of both the cadherin-based cell- cell adhesion and the tight junction, but not essential for the Rac subfamily-regulated, cadherin based cell- cell adhesion. PMID- 9362523 TI - CpG oligodeoxynucleotides act as adjuvants that switch on T helper 1 (Th1) immunity. AB - Synthetic oligodeoxynucleotides (ODN) that contain unmethylated CpG motifs (CpG ODN) induce macrophages to secrete IL-12, which induces interferon (IFN)-gamma secretion by natural killer (NK) cells. Since these cytokines can induce T helper 1 (Th1) differentiation, we examined the effects of coadministered CpG ODN on the differentiation of Th responses to hen egg lysozyme (HEL). In both BALB/c (Th2 biased) and B10.D2 (Th1-biased) mice, immunization with HEL in incomplete Freund's adjuvant (IFA) resulted in Th2-dominated immune responses characterized by HEL-specific secretion of IL-5 but not IFN-gamma. In contrast, immunization with IFA-HEL plus CpG ODN switched the immune response to a Th1-dominated cytokine pattern, with high levels of HEL-specific IFN-gamma secretion and decreased HEL-specific IL-5 production. IFA-HEL plus CpG ODN also induced anti HEL IgG2a (a Th1-associated isotype), which was not induced by IFA-HEL alone. Control non-CpG ODN did not induce IFN-gamma or IgG2a, excepting lesser increases in B10.D2 (Th1-biased) mice. Thus, CpG ODN provide a signal to switch on Th1 dominated responses to coadministered antigen and are potential adjuvants for human vaccines to elicit protective Th1 immunity. PMID- 9362524 TI - Regulation of the phosphorylation of human pharyngeal cell proteins by group A streptococcal surface dehydrogenase: signal transduction between streptococci and pharyngeal cells. AB - Whether cell-to-cell communication results when group A streptococci interact with their target cells is unknown. Here, we report that upon contact with cultured human pharyngeal cells, both whole streptococci and purified streptococcal surface dehydrogenase (SDH) activate pharyngeal cell protein tyrosine kinase as well as protein kinase C, thus regulating the phosphorylation of cellular proteins. SDH, a major surface protein of group A streptococci, has both glyceraldehyde-3-phosphate dehydrogenase and ADP-ribosylating enzyme activities that may relate to early stages of streptococcal infection. Intact streptococci and purified SDH induce a similar protein phosphorylation pattern with the de novo tyrosine phosphorylation of a 17-kD protein found in the membrane/particulate fraction of the pharyngeal cells. However, this phosphorylation required the presence of cytosolic components. NH2-terminal amino acid sequence analysis identified the 17-kD protein as nuclear core histone H3. Both phosphotyrosine and phosphoserine-specific monoclonal antibodies reacted with the 17-kD protein by Western blot, suggesting that the binding of SDH to these pharyngeal cells elicits a novel signaling pathway that ultimately leads to activation of histone H3-specific kinases. Genistein-inhibitable phosphorylation of histone H3 indicates that tyrosine kinase plays a key role in this event. Treatment of pharyngeal cells with protein kinase inhibitors such as genistein and staurosporine significantly inhibited streptococcal invasion of pharyngeal cells. Therefore, these data indicated that streptococci/SDH-mediated phosphorylation plays a critical role in bacterial entry into the host cell. To identify the membrane receptor that elicits these signaling events, we found that SDH bound specifically to 30- and 32-kD membrane proteins in a direct ligand binding assay. These findings clearly suggest that SDH plays an important role in cellular communication between streptococci and pharyngeal cells that may be important in host cell gene transcription, and hence in the pathogenesis of streptococcal infection. PMID- 9362525 TI - Cytotoxic T lymphocyte antigen 4 (CTLA-4) interferes with extracellular signal regulated kinase (ERK) and Jun NH2-terminal kinase (JNK) activation, but does not affect phosphorylation of T cell receptor zeta and ZAP70. AB - Cytotoxic T lymphocyte antigen 4 (CTLA-4) is an important regulator of T cell homeostasis. Ligation of this receptor leads to prominent downregulation of T cell proliferation, mainly as a consequence of interference with IL-2 production. We here report that CTLA-4 engagement strikingly selectively shuts off activation of downstream T cell receptor (TCR)/CD28 signaling events, i.e., activation of the microtubule-associated protein kinase (MAPKs) ERK and JNK. In sharp contrast, proximal TCR signaling events such as ZAP70 and TCR-zeta chain phosphorylation are not affected by CTLA-4 engagement on activated T cells. Since activation of the ERK and JNK kinases is required for stimulation of interleukin (IL)-2 transcription, these data provide a molecular explanation for the block in IL-2 production imposed by CTLA-4. PMID- 9362526 TI - Murine transporter associated with antigen presentation (TAP) preferences influence class I-restricted T cell responses. AB - The transporter associated with antigen presentation (TAP) complex shuttles cytosolic peptides into the exocytic compartment for association with nascent major histocompatibility complex class I molecules. Biochemical studies of murine and human TAP have established that substrate length and COOH-terminal residue identity are strong determinants of transport efficiency. However, the existence of these specificities in the intact cell and their influences on T cell responses have not been demonstrated. We have devised a method for studying TAP- mediated transport in intact cells, using T cell activation as a readout. The approach makes use of a panel of recombinant vaccinia viruses expressing peptides containing the Kd-restricted nonamer influenza nucleoprotein residues 147-155. The COOH terminus of each construct was appended with a dipeptide composed of an internal threonine residue followed by a varying amino acid. Synthetic peptide versions of these 11-mers exhibit vastly different transport capabilities in streptolysin O-permeabilized cells, in accordance with the predicted influence of the COOH-terminal residues. Presentation of the endogenously expressed version of each construct requires TAP-mediated transport and cooexpression with a vac encoded exocytic COOH-terminal dipeptidase, angiotensin converting enzyme, to allow liberation of the minimal epitope. Recognition by epitope-specific CTLs therefore signifies TAP-mediated transport of a complete 11-mer within the target cell. Under normal assay conditions no influences of the COOH-terminal residue were revealed. However, when T cell recognition was limited, either by blocking CD8 coreceptor interactions or by decreasing the amount of transport substrate synthesized, significant COOH-terminal effects were revealed. Under such conditions, those peptides that transported poorly in biochemical assays were less efficiently presented. Therefore, TAP specificity operates in the intact cell, appears to reflect previously defined rules with regard to the influence of the COOH-terminal residue, and can strongly influence T cell responses. PMID- 9362527 TI - Spontaneous autoimmune diabetes in monoclonal T cell nonobese diabetic mice. AB - It has been established that insulin-dependent diabetes mellitus (IDDM) in nonobese diabetic (NOD) mice results from a CD4+ and CD8+ T cell-dependent autoimmune process directed against the pancreatic beta cells. The precise roles that beta cell-reactive CD8+ and CD4+ T cells play in the disease process, however, remain ill defined. Here we have investigated whether naive beta cell specific CD8+ and CD4+ T cells can spontaneously accumulate in pancreatic islets, differentiate into effector cells, and destroy beta cells in the absence of other T cell specificities. This was done by introducing Kd- or I-Ag7-restricted beta cell-specific T cell receptor (TCR) transgenes that are highly diabetogenic in NOD mice (8.3- and 4.1-TCR, respectively), into recombination-activating gene (RAG)-2-deficient NOD mice, which cannot rearrange endogenous TCR genes and thus bear monoclonal TCR repertoires. We show that while RAG-2(-/-) 4.1-NOD mice, which only bear beta cell-specific CD4+ T cells, develop diabetes as early and as frequently as RAG-2+ 4.1-NOD mice, RAG-2(-/-) 8.3-NOD mice, which only bear beta cell-specific CD8+ T cells, develop diabetes less frequently and significantly later than RAG-2(+) 8.3-NOD mice. The monoclonal CD8+ T cells of RAG-2(-/-) 8.3 NOD mice mature properly, proliferate vigorously in response to antigenic stimulation in vitro, and can differentiate into beta cell-cytotoxic T cells in vivo, but do not efficiently accumulate in islets in the absence of a CD4+ T cell derived signal, which can be provided by splenic CD4+ T cells from nontransgenic NOD mice. These results demonstrate that naive beta cell- specific CD8+ and CD4+ T cells can trigger diabetes in the absence of other T or B cell specificities, but suggest that efficient recruitment of naive diabetogenic beta cell-reactive CD8+ T cells to islets requires the assistance of beta cell-reactive CD4+ T cells. PMID- 9362528 TI - Regulation of experimental autoimmune encephalomyelitis by natural killer (NK) cells. AB - In this report, we establish a regulatory role of natural killer (NK) cells in experimental autoimmune encephalomyelitis (EAE), a prototype T helper cell type 1 (Th1)-mediated disease. Active sensitization of C57BL/6 (B6) mice with the myelin oligodendrocyte glycoprotein (MOG)35-55 peptide induces a mild form of monophasic EAE. When mice were deprived of NK cells by antibody treatment before immunization, they developed a more serious form of EAE associated with relapse. Aggravation of EAE by NK cell deletion was also seen in beta 2-microglobulin-/- (beta 2m-/-) mice, indicating that NK cells can play a regulatory role in a manner independent of CD8+ T cells or NK1.1+ T cells (NK-T cells). The disease enhancement was associated with augmentation of T cell proliferation and production of Th1 cytokines in response to MOG35-55. EAE passively induced by the MOG35-55-specific T cell line was also enhanced by NK cell deletion in B6, beta 2m-/-, and recombination activation gene 2 (RAG-2)-/- mice, indicating that the regulation by NK cells can be independent of T, B, or NK-T cells. We further showed that NK cells inhibit T cell proliferation triggered by antigen or cytokine stimulation. Taken together, we conclude that NK cells are an important regulator for EAE in both induction and effector phases. PMID- 9362529 TI - Antibodies that inhibit malaria merozoite surface protein-1 processing and erythrocyte invasion are blocked by naturally acquired human antibodies. AB - Merozoite surface protein-1 (MSP-1) of the human malaria parasite Plasmodium falciparum undergoes at least two endoproteolytic cleavage events during merozoite maturation and release, and erythrocyte invasion. We have previously demonstrated that mAbs which inhibit erythrocyte invasion and are specific for epitopes within a membrane-proximal, COOH-terminal domain of MSP-1 (MSP-119) prevent the critical secondary processing step which occurs on the surface of the extracellular merozoite at around the time of erythrocyte invasion. Certain other anti-MSP-119 mAbs, which themselves inhibit neither erythrocyte invasion nor MSP 1 secondary processing, block the processing-inhibitory activity of the first group of antibodies and are termed blocking antibodies. We have now directly quantitated antibody-mediated inhibition of MSP-1 secondary processing and invasion, and the effects on this of blocking antibodies. We show that blocking antibodies function by competing with the binding of processing-inhibitory antibodies to their epitopes on the merozoite. Polyclonal rabbit antibodies specific for certain MSP-1 sequences outside of MSP-119 also act as blocking antibodies. Most significantly, affinity-purified, naturally acquired human antibodies specific for epitopes within the NH2-terminal 83-kD domain of MSP-1 very effectively block the processing-inhibitory activity of the anti-MSP-119 mAb 12.8. The presence of these blocking antibodies also completely abrogates the inhibitory effect of mAb 12.8 on erythrocyte invasion by the parasite in vitro. Blocking antibodies therefore (a) are part of the human response to malarial infection; (b) can be induced by MSP-1 structures unrelated to the MSP-119 target of processing-inhibitory antibodies; and (c) have the potential to abolish protection mediated by anti-MSP-119 antibodies. Our results suggest that an effective MSP-119-based falciparum malaria vaccine should aim to induce an antibody response that prevents MSP-1 processing on the merozoite surface. PMID- 9362530 TI - Characterization of an adhesion molecule that mediates leukocyte rolling on 24 h cytokine- or lipopolysaccharide-stimulated bovine endothelial cells under flow conditions. AB - Bovine gamma/delta T cells and neutrophils roll on 24 h cytokine- or lipopolysaccharide-stimulated bovine fetal umbilical cord endothelial cells in assays done under physiological flow. An antibody directed against E- and L selectin has minimal blocking effect on this rolling interaction. mAbs were raised against the stimulated bovine endothelial cells and screened for inhibition of gamma/delta T cell rolling. One mAb (GR113) was identified that recognizes an antigen (GR antigen) selectively expressed by stimulated bovine endothelial cells isolated from fetal umbilical cord, mesenteric lymph nodes, and aorta. GR113 blocked bovine gamma/delta T cell as well as neutrophil rolling on the 24 h-activated endothelial cells. The GR antigen was constitutively expressed at low levels on the cell surface of platelets and its expression was not upregulated after stimulation of these cells with thrombin or phorbol myristate acetate. However, stimulated platelets released a soluble, functionally active form of the molecule that selectively bound in solution to gamma/delta T cells in a mixed lymphocyte preparation. GR113 mAb blocked the binding of the soluble platelet molecule to the gamma/delta T cells. Soluble GR antigen also bound a subset of human lymphocytes. Cutaneous lymphocyte-associated antigen (CLA) bright human lymphocytes exhibited the greatest capacity to bind the GR antigen, though CLA was not required for binding. Subsets of both human CD4 and CD8 T cells bound the GR antigen. Immunoprecipitation experiments showed the GR antigen to be 110 120 kD Mr. The binding of soluble GR antigen was inhibited by EDTA and O sialoglycoprotease, but not neuraminidase treatment of the target cells. PMID- 9362531 TI - Regulation of ZAP-70 intracellular localization: visualization with the green fluorescent protein. AB - To investigate the cellular dynamics of ZAP-70, we have studied the distribution and regulation of its intracellular location using a ZAP-70 green fluorescent protein chimera. Initial experiments in epithelial cells indicated that ZAP-70 is diffusely located throughout the quiescent cell, and accumulates at the plasma membrane upon cellular activation, a phenotype enhanced by the coexpression of Lck and the initiation of ZAP-70 kinase activity. Subsequent studies in T cells confirmed this phenotype. Intriguingly, a large amount of ZAP-70, both chimeric and endogenous, resides in the nucleus of quiescent and activated cells. Nuclear ZAP-70 becomes tyrosine phosphorylated upon stimulation via the T cell receptor, indicating that it may have an important biologic function. PMID- 9362533 TI - Induction of airway mucus production By T helper 2 (Th2) cells: a critical role for interleukin 4 in cell recruitment but not mucus production. AB - Airway inflammation is believed to stimulate mucus production in asthmatic patients. Increased mucus secretion is an important clinical symptom and contributes to airway obstruction in asthma. Activated CD4 Th1 and Th2 cells have both been identified in airway biopsies of asthmatics but their role in mucus production is not clear. Using CD4 T cells from mice transgenic for the OVA specific TCR, we studied the role of Th1 and Th2 cells in airway inflammation and mucus production. Airway inflammation induced by Th2 cells was comprised of eosinophils and lymphocytes; features found in asthmatic patients. Additionally, there was a marked increase in mucus production in mice that received Th2 cells and inhaled OVA, but not in mice that received Th1 cells. However, OVA-specific Th2 cells from IL-4-deficient mice were not recruited to the lung and did not induce mucus production. When this defect in homing was overcome by administration of TNF-alpha, IL-4 -/- Th2 cells induced mucus as effectively as IL-4 +/+ Th2 cells. These studies establish a role for Th2 cells in mucus production and dissect the effector functions of IL-4 in these processes. These data suggest that IL-4 is crucial for Th2 cell recruitment to the lung and for induction of inflammation, but has no direct role in mucus production. PMID- 9362532 TI - Alpha 6 integrins are required for Langerhans cell migration from the epidermis. AB - Topical exposure of mice to chemical allergens results in the migration of epidermal Langerhans cells (LCs) from the skin and their accumulation as immunostimulatory dendritic cells (DCs) in draining lymph nodes. Epidermal cell derived cytokines have been implicated in the maturation and migration of LCs, but the adhesion molecules that regulate LC migration have not been studied. We hypothesized that integrin-mediated interactions with extracellular matrix components of the skin and lymph node may regulate LC/DC migration. We found that alpha 6 integrins and alpha 4 integrins were differentially expressed by epidermal LCs and lymph node DCs. A majority of LCs (70%) expressed the alpha 6 integrin subunit, whereas DCs did not express alpha 6 integrins. In contrast, the alpha 4 integrin subunit was expressed at high levels on DCs but at much lower levels on LCs. The anti-alpha 6 integrin antibody, GoH3, which blocks binding to laminin, completely prevented the spontaneous migration of LCs from skin explants in vitro and the rapid migration of LCs from mouse ear skin induced after intradermal administration of TNF-alpha in vivo. GoH3 also reduced the accumulation of DCs in draining lymph nodes by a maximum of 70% after topical administration of the chemical allergen oxazolone. LCs remaining in the epidermis in the presence of GoH3 adopted a rounded morphology, rather than the interdigitating appearance typical of LCs in naive skin, suggesting that the cells had detached from neighboring keratinocytes and withdrawn cellular processes in preparation for migration, but were unable to leave the epidermis. The anti-alpha 4 integrin antibody PS/2, which blocks binding to fibronectin, had no effect on LC migration from the epidermis either in vitro or in vivo, or on the accumulation of DCs in draining lymph nodes after oxazolone application. RGD containing peptides were also without effect on LC migration from skin explants. These results identify an important role for alpha 6 integrins in the migration of LC from the epidermis to the draining lymph node by regulating access across the epidermal basement membrane. In contrast, alpha 4 integrins, or other integrin-dependent interactions with fibronectin that are mediated by the RGD recognition sequence, did not influence LC migration from the epidermis. In addition, alpha 4 integrins did not affect the accumulation of LCs as DCs in draining lymph nodes. PMID- 9362535 TI - Defects in macrophage recruitment and host defense in mice lacking the CCR2 chemokine receptor. AB - Chemokines are a structurally related family of cytokines that are important for leukocyte trafficking. The C-C chemokine monocyte chemoattractant protein-1 (MCP 1) is a potent monocyte activator in vitro and has been associated with monocytic infiltration in several inflammatory diseases. One C-C chemokine receptor, CCR2, has been identified that mediates in vitro responses to MCP-1 and its close structural homologues. CCR2 has also recently been demonstrated to be a fusion cofactor for several HIV isolates. To investigate the normal physiological function of CCR2, we generated mice with a targeted disruption of the ccr2 gene. Mice deficient for CCR2 developed normally and had no hematopoietic abnormalities. However, ccr2(-/-) mice failed to recruit macrophages in an experimental peritoneal inflammation model. In addition, these mice were unable to clear infection by the intracellular bacteria, Listeria monocytogenes. These results suggest that CCR2 has a nonredundant role as a major mediator of macrophage recruitment and host defense against bacterial pathogens and that MCP 1 and other CCR2 ligands are effectors of those functions. PMID- 9362536 TI - Evidence that singlet oxygen-induced human T helper cell apoptosis is the basic mechanism of ultraviolet-A radiation phototherapy. AB - Ultraviolet A (UVA) irradiation is effectively used to treat patients with atopic dermatitis and other T cell mediated, inflammatory skin diseases. In the present study, successful phototherapy of atopic dermatitis was found to result from UVA radiation-induced apoptosis in skin-infiltrating T helper cells, leading to T cell depletion from eczematous skin. In vitro, UVA radiation-induced human T helper cell apoptosis was mediated through the FAS/FAS-ligand system, which was activated in irradiated T cells as a consequence of singlet oxygen generation. These studies demonstrate that singlet oxygen is a potent trigger for the induction of human T cell apoptosis. They also identify singlet oxygen generation as a fundamental mechanism of action operative in phototherapy. PMID- 9362534 TI - Suppressive role of B cells in chronic colitis of T cell receptor alpha mutant mice. AB - The role of antibodies (Abs) in the development of chronic colitis in T cell receptor (TCR)-alpha-/- mice was explored by creating double mutant mice (TCR alpha-/- x immunoglobulin (Ig)mu-/-), which lack B cells. TCR-alpha-/- x Ig mu-/- mice spontaneously developed colitis at an earlier age, and the colitis was more severe than in TCR-alpha-/- mice. Colitis was induced in recombination-activating gene-1 (RAG-1-/-) mice by the transfer of mesenteric lymph node (MLN) cells from TCR-alpha-/- x Ig mu-/- mice. When purified B cells from TCR-alpha-/- mice were mixed with MLN cells before cell transfer, colitis did not develop in RAG-1-/- mice. Administration of the purified Ig from TCR-alpha-/- mice and a mixture of monoclonal autoAbs reactive with colonic epithelial cells led to attenuation of colitis in TCR-alpha-/- x Ig mu-/- mice. Apoptotic cells were increased in the colon, MLN, and spleen of TCR-alpha-/- x Ig mu-/- mice as compared to Ig mu-/- mice and TCR-alpha-/- mice. Administration of the purified Ig from TCR-alpha-/- mice into TCR-alpha-/- x Ig mu-/- mice led to decrease in the number of apoptotic cells. These findings suggest that although B cells are not required for the initiation of colitis, B cells and Igs (autoAbs) can suppress colitis, presumably by affecting the clearance of apoptotic cells. PMID- 9362537 TI - Major histocompatibility complex class I molecules modulate activation threshold and early signaling of T cell antigen receptor-gamma/delta stimulated by nonpeptidic ligands. AB - Killer cell inhibitory receptors and CD94-NKG2-A/B heterodimers are major histocompatibility complex class I-specific inhibitory receptors expressed by natural killer cells, T cell antigen receptor (TCR)-gamma/delta cells, and a subset of TCR-alpha/beta cells. We studied the functional interaction between TCR gamma/delta and CD94, this inhibitory receptor being expressed on the majority of gamma/delta T cells. When engaged by human histocompatibility leukocyte antigen class I molecules, CD94 downmodulates activation of human TCR-gamma/delta by phosphorylated ligands. CD94-mediated inhibition is more effective at low than at high doses of TCR ligand, which may focus T cell responses towards antigen presenting cells presenting high amounts of antigen. CD94 engagement has major effects on TCR signaling cascade. It facilitates recruitment of SHP-1 phosphatase to TCR-CD3 complex and affects phosphorylation of Lck and ZAP-70 kinase, but not of CD3 zeta chain upon TCR triggering. These events may cause abortion of proximal TCR-mediated signaling and set a higher TCR activation threshold. PMID- 9362538 TI - Quantitative contribution of CD4 and CD8 to T cell antigen receptor serial triggering. AB - CD4 and CD8 are thought to function as coreceptors by binding to the cognate major histocompatibility complex (MHC) molecules recognized by the T cell antigen receptor (TCR) and initiating the signal transduction cascade. We report that during T cell-antigen-presenting cell interaction, triggered TCRs and coreceptors are downregulated and degraded with identical kinetics. This coordinated disappearance takes place whenever the TCR is triggered, even when the coreceptor does not engage the cognate MHC molecule and is the consequence of binding of the coreceptor-associated Lck to ZAP-70. The interaction of coreceptor and cognate MHC molecules is dispensable when T cells are stimulated by optimal ligands, but becomes crucial when suboptimal ligands are used. In the latter case the coreceptor increases the efficiency of TCR triggering without changing the activation threshold or the quality of the T cell response. PMID- 9362539 TI - In vitro- and ex vivo-derived cytolytic leukocytes from granzyme A x B double knockout mice are defective in granule-mediated apoptosis but not lysis of target cells. AB - Granzyme (gzm) A and gzmB have been implicated in Fas-independent nucleolytic and cytolytic processes exerted by cytotoxic T (Tc) cells, but the underlying mechanism(s) remains unclear. In this study, we compare the potential of Tc and natural killer (NK) cells of mice deficient in both gzmA and B (gzmAxB-/-) with those from single knockout mice deficient in gzmA (-/-), gzmB (-/-), or perforin (-/-) to induce nuclear damage and lysis in target cells. With the exception of perforin-/-, all in vitro- and ex vivo-derived Tc and NK cell populations from the mutant strains induced 51Cr-release in target cells at levels and with kinetics similar to those of normal mice. This contrasts with their capacity to induce apoptotic nuclear damage in target cells. In gzmAxB-/- mice, Tc/NK mediated target cell DNA fragmentation was not observed, even after extended incubation periods (10 h), but was normal in gzmA-deficient and only impaired in gzmB-deficient mice in short-term (2-4 h), but not long-term (4-10 h), nucleolytic assays. This suggests that gzmA and B are critical for Tc/NK granule- mediated nucleolysis, with gzmB being the main contributor, while target cell lysis is due solely to perforin and independent of both proteases. PMID- 9362540 TI - Costimulation by B7 modulates specificity of cytotoxic T lymphocytes: a missing link that explains some bystander T cell activation. AB - It has been proposed that some bystander T cell activation may in fact be due to T cell antigen receptor (TCR) cross-reactivity that is too low to be detected by the effector cytotoxic T lymphocyte (CTL). However, this hypothesis is not supported by direct evidence since no TCR ligand is known to induce T cell proliferation and differentiation without being recognized by the effector CTL. Here we report that transgenic T cells expressing a T cell receptor to influenza virus A/NT/68 nucleoprotein (NP) 366-374:Db complexes clonally expand and become effector CTLs in response to homologous peptides from either A/PR8/34 (H1N1), A/AA/60 (H2N2), or A/NT/68 (H3N2). However, the effector T cells induced by each of the three peptides kill target cells pulsed with NP peptides from the H3N2 and H2N2 viruses, but not from the H1N1 virus. Thus, NP366-374 from influenza virus H1N1 is the first TCR ligand that can induce T cell proliferation and differentiation without being recognized by CTLs. Since induction of T cell proliferation was mediated by antigen-presenting cells that express costimulatory molecules such as B7, we investigated if cytolysis of H1N1 NP peptide-pulsed targets can be restored by expressing B7-1 on the target cells. Our results revealed that this is the case. These data demonstrated that costimulatory molecule B7 modulates antigen specificity of CTLs, and provides a missing link that explains some of the bystander T cell activation. PMID- 9362541 TI - Signal transduction due to HIV-1 envelope interactions with chemokine receptors CXCR4 or CCR5. AB - Infection with HIV-1 requires expression of CD4 and the chemokine receptors CXCR4 or CCR5 at the target cell surface. Engagement of these receptors by the HIV-1 envelope glycoprotein is essential for membrane fusion, but may additionally activate intracellular signaling pathways. In this study, we demonstrate that chemokines and HIV-1 envelope glycoproteins from both T-tropic and macrophage tropic strains rapidly induce tyrosine phosphorylation of the protein tyrosine kinase Pyk2. The response requires CXCR4 and CCR5 to be accessible on the cell surface. The results presented here provide the first evidence for activation of an intracellular signaling event that can initiate multiple signaling pathways as a consequence of contact between HIV-1 and chemokine receptors. PMID- 9362542 TI - The localization of histone H3.3 in germ line chromatin of Drosophila males as established with a histone H3.3-specific antiserum. AB - A rabbit antiserum, specific for the histone H3.3 replacement variant, was raised with the aid of a histone H3.3-specific peptide. Immuno blot experiments demonstrated the specificity of this polyclonal antiserum. In addition, we showed on immuno blots that two monoclonal antibodies isolated from mice with systemic lupus erythematosus (SLE) display strong reactivity with the H3.3 histone, but not with its replication-dependent counterparts. Our observations indicate that histone H3.3 might play a role as autoantigen in SLE. We used the histone H3.3 specific antiserum to characterize the germ line chromatin in cytological preparations of Drosophila testes, because our previous studies had shown that a histone H3.3-encoding gene is strongly expressed in the germ line of Drosophila males. The antiserum reacted with some of the lampbrush loops in spermatocytes and with chromatin of the postmeiotic germ cells of males. Our data indicate that histone H3.3 is not evenly distributed throughout the chromatin of germ cells, but is concentrated in distinct regions. Histone H3.3 disappears from the spermatid nuclei, along with the other core histones, during the late stages of spermatogenesis. In Drosophila polytene chromosomes, however, a rather uniform distribution of the histone H3.3 was observed. The possible role of histone H3.3 is discussed. PMID- 9362543 TI - Mitosis-specific phosphorylation of histone H3 initiates primarily within pericentromeric heterochromatin during G2 and spreads in an ordered fashion coincident with mitotic chromosome condensation. AB - We have generated and characterized a novel site-specific antibody highly specific for the phosphorylated form of the amino-terminus of histone H3 (Ser10). In this study, we used this antibody to examine in detail the relationship between H3 phosphorylation and mitotic chromosome condensation in mammalian cells. Our results extend previous biochemical studies by demonstrating that mitotic phosphorylation of H3 initiates nonrandomly in pericentromeric heterochromatin in late G2 interphase cells. Following initiation, H3 phosphorylation appears to spread throughout the condensing chromatin and is complete in most cell lines just prior to the formation of prophase chromosomes, in which a phosphorylated, but nonmitotic, chromosomal organization is observed. In general, there is a precise spatial and temporal correlation between H3 phosphorylation and initial stages of chromatin condensation. Dephosphorylation of H3 begins in anaphase and is complete immediately prior to detectable chromosome decondensation in telophase cells. We propose that the singular phosphorylation of the amino-terminus of histone H3 may be involved in facilitating two key functions during mitosis: (1) regulate protein-protein interactions to promote binding of trans-acting factors that "drive" chromatin condensation as cells enter M-phase and (2) coordinate chromatin decondensation associated with M-phase. PMID- 9362544 TI - Complex alterations of the ribosomal gene spacers in mutant sc8 of Drosophila melanogaster. AB - Extreme changes in the proportions of the rDNA intergenic spacers (IGSs) have previously been demonstrated by us in the X-chromosomal rDNA array of the Drosophila melanogaster mutant sc8, where nearly all IGSs were found to be reduced in size. We have cloned different structural variants of the Xsc8 ribosomal units and mapped their spacers by restriction endonuclease analysis. Most of the IGSs exhibited complex rearrangements within the subrepeated region at their 5' terminus. The sequence data revealed the presence of an additional 100 bp subrepeat. In addition, extended deletions/substitutions down to the 18S gene were also found. Examination of the Ysc8 IGS polymorphism indicates that some of the X-chromosomal IGS variants are probably the result of X-Y interchanges. The rarity of alternative recombination products implies that the overabundant deleted spacers in sc8 are generated by nonreciprocal recombination. Our results demonstrate nonrandom distribution of deletional breakpoints within the "1900" region in sc8 and show that the deletions do not truncate the internal IGS subregions at either breakpoint but eliminate them as discrete blocks. PMID- 9362545 TI - NTRS, a new family of highly repetitive DNAs specific for the T1 chromosome of tobacco. AB - Species-specific repeated DNAs are important for identifying genomic components of hybrid organisms in plant breeding and in taxonomic studies, and we have previously described the HRS60 and GRS families of highly repetitive DNA sequences in tobacco. Here we describe a new family of highly repetitive DNA sequences termed NTRS (SspI family) that we have isolated from Nicotiana tomentosiformis (Goodspeed) and characterized and that is specific for the genomes of several species of the subgenus Tabacum. In situ hybridization showed that NTRS sequences are present in three pairs of chromosomes of N. tomentosiformis, six pairs of chromosomes of N. kawakamii, and only one pair of chromosomes of N. tabacum at an intercalary site. The NTRS family is not present in the N. otophora genome. The majority of NTRS sequences appeared to be organized in tandem arrays in which local DNA structures sensitive to single strand-specific chemical probes, potassium permanganate, and osmium tetroxide complexed with pyridine revealed a periodicity of 220 bp, equal to the length of the repeat unit. The inner cytosine in CCGG and CC(A/T)GG sequences of the NTRS family is frequently methylated. Cloned and sequenced NTRS monomeric units are 212-219 bp in length and show 83.5%-95% mutual homology. They exhibit properties characteristic for molecules that possess stable intrinsic curvature, but there are differences among individual monomers in the degree of curvature. NTRS sequences like HRS60 and GRS sequences, were found to specify nucleosome positions. PMID- 9362546 TI - Genomic organization of the yeast Yarrowia lipolytica. AB - We produced electrophoretic karyotypes of the reference strain E150 and of seven other isolates from different geographical origins to study the genomic organization of the dimorphic yeast Yarrowia lipolytica. These karyotypes differed in the number and size of the chromosomal bands. The karyotype of the reference stain E150 consisted of five bands of between 2.6 and 4.9 Mb in size. This strain contained at least five rDNA clusters, from 190 to 620 kb in size, which were scattered over most of the chromosomes. The assignment of 43 markers, including rRNA genes and three centromeres, to the E150 bands defined five linkage groups. Hybridization to the karyotypes of other isolates with pools of markers of each linkage group showed that linkage groups I, II, IV and V were conserved in the strains tested whereas group III was not and was split between at least two chromosomes in most strains. Use of a meganuclease I-SceI site targeted to one locus of E150 linkage group III showed that two chromosomes actually comigrated in band III of this strain. Our results are compatible with six chromosomes defining the haploid complement of strains of Y. lipolytica and that, despite an unprecedented chromosome length polymorphism, the overall structure of the genome is conserved in different isolates. PMID- 9362547 TI - Localization of chromosome breakpoints induced by DNase I in Chinese hamster ovary (CHO) cells. AB - DNase I was electroporated into S-phase CHO cells and induced chromosome breakpoints were localized in G-banded metaphases. More than 75% of breakpoints mapped to Giemsa-light bands, 18% to Giemsa-dark bands and about 7% to band junctions. Chromosome breakpoint clusters produced by DNase I colocalized with chromosome breakpoints induced by the restriction endonucleases AluI and BamHI in the G1- and S-phases of the cell cycle in CHO cells. Digestion of metaphase spreads with AluI, BamHI and DNase I produced G-bands, indicating that G-light bands are more sensitive to endonuclease action. The possible role of nuclease sensitive sites in active chromatin as selective targets for the induction of chromosome breakpoints by these endonucleases is discussed. PMID- 9362548 TI - Expression of three rare fragile sites: chromosomal truncation, amplification of distal segment and telomeric renewal. AB - Fluorescence in situ hybridization with a telomeric probe was used to monitor telomeric renewal following breakage induced by the rare fragile sites FRA10A, FRA12A and FRA16B. Interstitial telomere-like sequences were detected only at the break sites of FRA10A. PMID- 9362549 TI - DNA replication asynchrony between the paternal and maternal alleles of imprinted genes does not straddle the R/G transition. AB - Imprinted autosomal loci apparently reside in very large chromosomal domains that exhibit asynchrony in replication of homologous alleles during the DNA synthesis phase. Replication asynchrony can be cytogenetically visualized by a replication banding discordance between homologous bands of a given pair of chromosomal homologs. The replication time of a chromosomal band at high resolution can be determined by blocking DNA synthesis at the R/G-band transition and using replication banding. The R/G transition reflects the transition from early (R-) to late (G- and C-) band DNA replication. We studied discordance between two groups of homologous chromosomal bands: (a) four bands, 6q26-27, 11p13, 11p15.5 and 15q11.2-12, each containing at least one imprinted gene; and (b) nine bands containing no known imprinted genes. Fifty pairs of chromosomes were analyzed at high resolution after R/G transition blocking and late 5-bromo-2'-deoxyuridine incorporation. The rate of discordance was the same for bands containing imprinted genes and for control bands. Both homologous bands of a pair replicate either before or after the R/G transition and do not straddle the R/G transition. Repression associated with imprinting does not appear to involve late replication at the band level of resolution. Tissue-specific inactivation is associated with DNA methylation and late replication, whereas allele-specific inactivation is associated with DNA methylation but not with delayed or late replication. PMID- 9362550 TI - Total synthesis of (+/-)-monomorine I and (+/-)-indolizidine 195B by an aza-[2,3] Wittig rearrangement of a vinylaziridine. AB - A novel synthesis of (+/-)-monomorine I (1) and (+/-)-indolizidine 195B (2) is described in which the key step is the highly efficient aza-[2,3]-Wittig rearrangement of vinylaziridine 12 into tetrahydropyridine 13. Functional group manipulation then gave ketone 16 which could be converted into the target alkaloids by reductive amination (1:2 1.5:1). PMID- 9362551 TI - endo and exo isomers of isodicyclopentadienyltrichlorotitanium. AB - The diastereomeric endo and exo isomers of the title complex, [TiCl3(C10H11)], have been synthesized by electrophilic attack of TiCl4 on the exo- or endo trimethylsilyl derivative of isodiCp (isodiCp = isodicyclopentadiene). This reaction proceeds with net inversion of configuration to give exclusively either the endo- or exo-(isodiCp)TiCl3 compound. Although the two isomers have similar unit-cell constants, they crystallize in different space groups. The endo complex, (2), is in Pbcm with a crystallographic mirror plane, while the exo complex, (4), is in Pca2(1) with pseudo-mirror symmetry. Both molecules display a distorted tetrahedral geometry about the Ti atom. Each Ti atom is bonded in a eta(5) manner to the Cp ring of the isodiCp ligand, with Ti--ring centroid distances of 2.031 (2) and 2.013 (2) A for (2) and (4), respectively. A slight bending of the isodiCp ligand about the bond shared by the Cp ring and the norbornane fragment is observed in both structures. The determination of the absolute structure of (4) defines the directionality of the packing along the polar c axis. PMID- 9362552 TI - 1,4-dimethoxy-2-naphthoic acid. AB - The title compound, C13H12O4, crystallized in the centrosymmetric space group P2(1)/c and exhibits cyclic dimer hydrogen bonding about a center of symmetry. The carboxylic H atom is modeled as disordered over two half-occupancy sites. Overall, the hydrogen bonding is little affected by the methoxyl groups and is very similar to that in 2-naphthoic acid. PMID- 9362553 TI - 2-Aminonicotinic acid. AB - 2-Aminonicotinic acid, C6H6N2O2, crystallized in the centrosymmetric space group P2(1)/c in the zwitterionic form. Intermolecular N--H...O hydrogen bonds with N...O distances of 2.652 (2) and 2.807 (2) A link molecules into two sets of zigzag chains propagating along the b axis. The two sets of chains are crosslinked by C--H...O interactions. The dihedral angle between the planes of adjacent molecules in a chain is 9.77 (7) degrees. An intramolecular N--H...O hydrogen bond is also present. PMID- 9362554 TI - Tyrosinium-D-tetrahydroisoquinoline-3-carboxylate 1.5-hydrate and tyrosyl-D tetrahydroisoquinoline-3-carboxamide hydrate. AB - Crystals of the two dipeptide title compounds, Tyr-D-Tic, C19H20N2O4.1.5H2O, and Tyr-D-Tic-NH2, C19H21N3O3.H2O, were prepared by the sitting-drop method. Tyr-D Tic is orthorhombic (P2(1)2(1)2(1)) and crystallizes as a zwitterion. The asymmetric unit contains two peptide molecules and three molecules of water. Tyr D-Tic-NH2 crystals are monoclinic (P2(1)), the asymmetric unit containing one peptide molecule and one molecule of water. Despite some differences in packing, the conformation of the two dipeptides is almost identical (r.m.s. deviation for non-H atoms is approximately 0.18 A). PMID- 9362555 TI - Relative and absolute configuration of aloperine. AB - The relative and absolute configuration of the title compound, (6R,7R,9R,11S) 16,17-didehydro-9-de-2-piperidinylormosanine, C15H24N2, has been elucidated. Two X-ray structures, one of the free base of the alkaloid and the second of its dihydrochloride monohydrate salt, C15H26N2(2+).2Cl-.H2O, have been determined to unequivocally establish the stereochemistry of aloperine, the parent member of a rare family of lupinine alkaloids. PMID- 9362556 TI - Graphs in sequence spaces: a review of statistical geometry. AB - Statistical geometry is a method of comparative sequence analysis of genes. Based on the concept of the sequence space of nucleic acids it computes the geometries of sequence sets, mainly quartets, by combining both the vertical and horizontal information content of the sequences. The geometries can be used to deduce, for example, the degree of tree-likeness of the data set without any a priori assumption of an evolution model. Furthermore, statistical geometry allows to detect varying positional substitution rates in sequences. Applications of the method to tRNA sequences have provided an assessment for the age of the genetic code. Furthermore, applications of statistical geometry to homeoboxes as well as different virus families have helped to assign reliable kinship relationships. In addition, a lower bound for the age of the common ancestor of the human and simian immunodeficiency viruses has been established. PMID- 9362557 TI - Spatially resolved in vitro molecular ecology. AB - Sensitive CCD-based fluorescence detection has made spatially resolved studies of evolving cell-free molecular systems possible. In recent years our attention has focussed on making the transition to open and interacting spatially-resolved amplification systems using silicon microreactor technology and on providing a hardware platform for individual based simulation of such systems. Significant progress has been achieved in this direction. Open microflow reactors have been realized in zero (well-mixed), one and two dimensions with volumes small enough to allow long-time studies with limited biochemical materials. The primer directed 3SR reaction (amplifying DNA and RNA) has been used as a basis for constructing interacting model systems with both predator-prey and cooperative amplification character. Theoretical work has demonstrated the need for individual based modeling of such systems: a significant fraction of the population consists of distinct sequence polymers in any case. A massively parallel processor-configurable computer NGEN has been designed and constructed which allows the high speed simulation in hardware of relatively large populations of locally interacting individual strings of chosen length (e.g. up to 2000*2000 for 64 bases), in addition to its application as an evolvable hardware machine. Simulations show self-replicating spots to stabilize the cooperative amplification in evolving systems (a mechanism proposed by the author in 1994). Both oscillatory kinetics and pattern formation are expected in the experimental model systems under investigation which profoundly affect the course of evolution. Such in vitro model systems serve both to test current theories of cooperative evolution and provide clues for optimisation strategies in molecular biotechnology. PMID- 9362558 TI - Principles and methods of evolutionary biotechnology. AB - Evolutionary biotechnology applies the principles of molecular evolution to biotechnology, leading to novel techniques for the creation of biomolecules with a great variety of functions for technical and medical purposes. Several basic principles for the application of evolutionary strategies can be derived from a comprehensive theory of molecular evolution. Prerequisites for evolutionary biotechnology are summarized with respect to the different classes of biomolecules and a few, selected applications are described in detail. Concepts for the technical implementation of evolutionary strategies are presented which allow automatized, high throughput processes. PMID- 9362559 TI - Molecular evolution of RNA in vitro. AB - Experimental studies of RNA evolution in vitro are reviewed in the context of Eigen's 1971 theory and its subsequent extensions. Current research activity and future prospects for using automated molecular biology techniques for in vitro evolution experiments are surveyed. PMID- 9362560 TI - Kinetic investigations by fluorescence correlation spectroscopy: the analytical and diagnostic potential of diffusion studies. AB - This review demonstrates the large analytical and diagnostic potential of fluorescence correlation spectroscopy applied to freely diffusing biomolecules in solution. All applications discussed here in detail are based on changes in the diffusion characteristics of fluorescenctly labeled complementary strands of nucleic acids when they associate. However, the principle of the measurement can be extended to many different reactions with characteristic association times between several minutes up to several hours. If the reaction significantly affects the diffusion constants of at least one partner, single-color auto correlation analysis is sufficient to extract kinetic parameters. If the observed binding process has only a moderate effect on diffusion coefficients, the detection selectivity and sensitivity can be improved by dual-color cross correlation analysis. Finally, we show that diffusional analysis on the single molecule level even opens up diagnostic applications, such as the detection of minute amounts of infectious agents like HIV-1 viruses in blood. PMID- 9362561 TI - Prions and their biophysical background. PMID- 9362563 TI - Expression systems. PMID- 9362562 TI - Erythrocyte pyruvate kinase- and glucose phosphate isomerase deficiency: perturbation of glycolysis by structural defects and functional alterations of defective enzymes and its relation to the clinical severity of chronic hemolytic anemia. AB - The pathogenesis of two metabolic disorders caused by enzyme defects in the red blood cell leading to hemolytic anemia, and in some cases of glucose phosphate isomerase (GPI) deficiency additionally to neurological impairment was investigated. Rheological studies were performed to determine the influence of a shortage of energy on the deformability of the erythrocytes. The functions of the enzymes were determined by studying the enzyme kinetics, the temperature dependence of the enzyme activity and the migration of the proteins in an electric field. A detailed molecular genetic analysis of the gene encoding for the given protein allowed the detection of mutations involving amino acid exchanges which cause alterations of the protein structure. For both enzyme deficiencies, a good correlation was found between the structural changes (usually caused by single point mutations in the gene), the altered function of the enzymes and the severity of the clinical picture. The exchange of amino acids close to either the active site or the regulatory domain results in a decreased turnover as well as an alteration of the regulatory properties of the enzymes; this usually leads to an increased severity of the disease. Increased concentrations of glucose-6-phosphate (G-6-P), found in all red blood cells of patients suffering from hemolytic anemia caused by pyruvate kinase (PK) and GPI deficiency, correlate well with the severity of the clinical picture, apparently reflecting the degree of the perturbation of glycolysis. This results in a lack of the energy donor adenosine triphosphate (ATP); this leads then to a destabilization of the red cell membrane which causes earlier lysis of the red blood cell, which in turn gives rise to hemolytic anemia of variable degrees. One patient with neurological symptoms has been studied so far biochemically and at the molecular genetic level. The point mutations found in this patient's GPI gene support the idea that GPI may have a neurological function in addition to its role in the carbohydrate metabolism; this is due to the presence of a monomeric sequence analogue called neuroleukin (NLK). The mutations apparently lead to the incorrect folding of this neurotrophic factor, and thus destroy the neurological activity. PMID- 9362564 TI - Abscisic acid inhibits germination of mature Arabidopsis seeds by limiting the availability of energy and nutrients. AB - The addition of abscisic acid (ABA) to mature non-dormant seeds inhibits their germination. This effect of ABA might be related to its natural function as an endogenous inhibitor of precocious germination during seed formation. In this work, we studied how ABA affects the germination of mature seeds and the growth of nascent seedlings of Arabidopsis thaliana (L.) Heynh. Our findings were as follows: (i) inhibition by ABA was gradual, dose-dependent, and did not disappear after germination; (ii) inhibition of germination was relieved by the addition of metabolizable sugars or amino acids to the plating media; (iii) the effect of sugars and amino acids was cooperative, indicating that these two groups of metabolites relieve different deficiencies; (iv) ABA caused appreciable alterations in energy and nitrogen metabolism; and (v) ABA prevented the degradation of the seed storage proteins. In summary, ABA appears to inhibit seed germination by restricting the availability of energy and metabolites. This mechanism seems consistent with other known effects of ABA. PMID- 9362565 TI - Purification of an elicitor-induced glucan synthase (callose synthase) from suspension cultures of French bean (Phaseolus vulgaris L.): purification and immunolocation of a probable M(r)-65,000 subunit of the enzyme. AB - Membrane preparations from suspension-cultured cells of French bean (Phaseolus vulgaris L.) contained callose synthase (EC 2.4.1.34) activity which was preserved upon solubilisation. Following elicitor treatment of cell cultures, increased activity could be extracted and this increase was maintained during purification. The enzyme was purified by high-pressure liquid chromatography and active fractions showed a variable association of two polypeptides of relative molecular masses (M(r)) 55,000 and 65,000, the latter being in excess. The M(r) 65,000 polypeptide was purified to homogeneity and an antibody raised to it. This antibody showed complex effects on callose synthase activity when incubated with membrane and soluble extracts. In comparison with other systems, the M(r)-55,000 subunit is likely to represent the catalytic subunit while the M(r)-65,000 polypeptide is a possible regulatory subunit. The M(r)-65,000 polypeptide was immunolocated in membranes at sites of callose synthesis in the plant, in cell plates, in sieve plates, at the plasma membrane-wall interface of wounded cells and in papillae in infected cells. PMID- 9362566 TI - Cardosin A, an abundant aspartic proteinase, accumulates in protein storage vacuoles in the stigmatic papillae of Cynara cardunculus L. AB - The function of aspartic proteinases (EC 3.4.23) present in flowers of Cynara species is still unknown. Cardosin A, as a highly abundant aspartic proteinase from Cynara cardunculus L., a relative of the artichoke, is synthesised as a zymogen and subsequently undergoes proteolytic processing, yielding the mature and active enzyme. Here we report the study of the expression and localization of cardosin A, as a first approach to address the question of its physiological relevance. A polyclonal antibody specific for cardosin A was raised against a synthetic peptide corresponding to an amino acid sequence of the enzyme. This antibody was used to study the organ-specific, tissue-specific and subcellular localization of cardosin A by immunoblotting, tissue printing and immunogold electron microscopy. The results showed that expression of cardosin A is highly restricted to the pistils, and that the enzyme accumulates mainly in protein storage vacuoles of the stigmatic papillae. Cardosin A is also present, although much less abundantly, in the vacuoles of the cells of the epidermis of the style. In view of these results, the possible physiological roles of cardosin A are discussed, namely an involvement in defense mechanisms or pollen-pistil interaction, as well as in flower senescence. PMID- 9362567 TI - Substratum adhesion and gliding in a diatom are mediated by extracellular proteoglycans. AB - Diatoms are unicellular microalgae encased in a siliceous cell wall, or frustule. Pennate diatoms, which possess bilateral symmetry, attach to the substratum at a slit in the frustule called the raphe. These diatoms not only adhere, but glide across surfaces whilst maintaining their attachment, secreting a sticky mucilage that forms a trail behind the gliding cells. We have raised monoclonal antibodies to the major cell surface proteoglycans of the marine raphid diatom Stauroneis decipiens Hustedt. The antibody StF.H4 binds to the cell surface, in the raphe and to adhesive trails and inhibits the ability of living diatoms to adhere to the substratum and to glide. Moreover, StF.H4 binds to a periodate-insensitive epitope on four frustule-associated proteoglycans (relative molecular masses 87, 112, and > 200 kDa). Another monoclonal antibody, StF.D5, binds to a carbohydrate epitope on the same set of proteoglycans, although the antibody binds only to the outer surface of the frustule and does not inhibit cell motility and adhesion. PMID- 9362568 TI - Kinetics of high-affinity K+ uptake in plants, derived from K(+)-induced changes in current-voltage relationships. A modelling approach to the analysis of carrier mediated transport. AB - To investigate coupled, charge-translocating transport, it is imperative that the specific transporter current-voltage (IV) relationship of the transporter is separated from the overall membrane IV relationship. We report here a case study in which the currents mediated by the K(+)-H+ symporter, responsible for high affinity K+ uptake in Arabidopsis thaliana (L.) Heynh. cv. Columbia roots, are analyzed with an enzyme kinetic reaction scheme. The model explicitly incorporates changes in membrane voltage and external substrate, and enables the derivation of the underlying symport IV relationships from the experimentally obtained difference IV data. Data obtained for high-affinity K+ transport in A. thaliana root protoplasts were best described by a 1:1 coupled K(+)-H+ symport mediated current with a parallel, outward non-linear K+ pathway. Furthermore, the large predictive value of the model was used to describe symport behaviour as a function of the external K+ concentration and the cytoplasmic K+ concentration. Symport activity is a complex function of the external K+ concentration, with first-order saturating kinetics in the micromolar range and a strong activity reduction when external K+ is in the millimolar range and the membrane depolarises. High cytoplasmic K+ levels inhibit symport activity. These responses are suggested to be part of the feedback mechanisms to maintain cellular K+ homeostasis. The general suitability of the model for analysis of carrier mediated transport is discussed. PMID- 9362569 TI - A vegetative storage protein homolog is expressed in the growing shoot apex of hybrid poplar. AB - The ability of poplars (Populus deltoides Bartr. ex Marsh., and Populus trichocarpa Torr. and Gray) to sequester nitrogen in stems in preparation for winter has been associated with the massive accumulation of protein bodies in the bark and xylem ray parenchyma. These protein bodies contain a bark storage protein (BSP) that can account for up to 30% of the total soluble bark protein during the winter months. Perhaps the plant's ability to efficiently cycle nitrogen through BSP is an important aspect of its growth potential. Sequence analysis of BSP led to the identification of a leaf-associated homolog, win4, which was initially isolated because its transcript increased in abundance upon mechanical wounding. The goal of this work was to characterize this putative leaf associated vegetative storage protein, and determine whether it might perform a storage role in vivo. Antibodies, produced against protein synthesized upon over expression of the win4 coding region in Escherichia coli, were used to examine the relative abundance of WIN4 protein in response to supplemental nitrogen, and during development. The transcript and protein were most abundant in the youngest leaves and also increased with nitrogen fertilization. Immunolocalization of the protein was performed and showed that WIN4 was associated with cells surrounding the vasculature, and cells of the lower epidermis and stipules of immature leaves. Under moderate nitrogen fertilization regimes, WIN4 accounted for only about 2% of total soluble leaf protein; however, given the cellular specificity and enhancement with nitrogen, the protein is regulated in a manner similar to other vegetative storage proteins. Since poplar is amenable to DNA transformation and regeneration, it is now possible to ask direct questions about the role these proteins play in nitrogen storage in rapidly expanding or in dormant tissue. This type of analysis could determine whether these proteins mainly ameliorate the toxic effects of excess nitrogen, if they are instrumental in controlling nitrogen allocation or if they simply represent an efficient method for sequestering this valuable nutrient. PMID- 9362570 TI - Assessment of pressure ulcer healing. PMID- 9362571 TI - Pressure ulcer classification: what do we have? What do we need? AB - This paper will lay the foundation for subsequent papers by: summarizing the limitations of the current pressure ulcer classification system exploring methods to monitor the dynamic process of pressure ulcer healing establishing common criteria for evaluating various methods of monitoring pressure ulcer healing. PMID- 9362572 TI - Draft definition of stage I pressure ulcers: inclusion of persons with darkly pigmented skin. NPUAP Task Force on Stage I Definition and Darkly Pigmented Skin. AB - The National Pressure Ulcer Advisory Panel appointed a task force to review the definition of Stage I pressure ulcers, specifically to assess its adequacy in people with darkly pigmented skin. The process used by the task force to draft a new definition is described in this preliminary report of their work. The proposed definition and initial critique of it are given. PMID- 9362573 TI - Pressure ulcer healing: what is it? What influences it? How is it measured? AB - Defining healing requires a set of measurements that quantify the physical factors that change during healing. Such a list of measures gives a de facto definition of what constitutes pressure ulcer healing and what influences it. This paper attempts to answer a more specific question: Which measurements are strong candidates for inclusion in a tool for monitoring pressure ulcer healing? Three sets of clinical measurements are analyzed--the assessment proposed by the Agency for Health Care Policy and Research Guideline Development Panel for the Treatment of Pressure Ulcers; the recommendations of the Wound Healing Society; and the Pressure Sore Status Tool. The validity of the 11 clinical measures common across these assessment methods is examined using empiric evidence from studies of wound healing. PMID- 9362574 TI - Will all pressure ulcers heal? AB - Clinicians today are faced with the need to justify their care through outcomes data. However, this is difficult with chronic, nonhealing wounds or pressure ulcers, which do not follow the expected trajectory of wound healing. Therefore, outcomes are unpredictable. This paper discusses the phases of wound healing and progress toward identifying outcomes for chronic wounds, as well as future directions in research. PMID- 9362575 TI - Policy implications of using reverse staging to monitor pressure ulcer status. AB - In 1995, the National Pressure Ulcer Advisory Panel held its Fourth National Conference, "Pressure Ulcer Healing: Controversy to Consensus, Assessment Methods and Outcomes." At that time, agreement was reached on uses and misuses of the current pressure ulcer staging system. Participants agreed that pressure ulcer staging definitions should not be used in reverse order to measure improvement in an ulcer. Negative outcomes of reverse staging were seen as (1) denial of acute or skilled care after Stage IV ulcers were restaged as Stage II ulcers; (2) withdrawal of pressure-reducing support surfaces when ulcers "healed" from Stage III or Stage IV to Stage II; and (3) lower fees paid to extended-care facilities for care of patients with healing Stage III and Stage IV ulcers that were reclassified as Stage II or Stage I pressure ulcers. PMID- 9362576 TI - The federal effort to eliminate fraud and ensure quality care. AB - In 1996, the United States filed a lawsuit against a nursing home that it alleged was providing inadequate nutrition and wound care to residents, despite the fact that the facility had submitted claims to Medicare and Medicaid for payment for nutrition services. The lawsuit alleged that these submissions for payment violated the False Claims Act. This was the first time the False Claims Act was used to enforce quality-of-care standards set by Congress in the Nursing Home Reform Act. A federal prosecutor involved in the case discusses the steps leading up to the lawsuit and the details of the settlement. PMID- 9362577 TI - Session II. Monitoring pressure ulcer healing. PMID- 9362578 TI - Tracking outcomes: the rehab professional's perspective. AB - Rehabilitation professionals contributing to the plan of care for a patient with a wound must be aware of and follow the rules promulgated by regulators, surveyors, and payers. Certain regulations are of particular importance. When establishing functional outcomes, the rehabilitation professional should ask whether the outcomes are meaningful, practical, and sustainable. By becoming part of the multidisciplinary team, rehabilitation professionals can help to improve cost-effectiveness of wound care and patient outcomes. PMID- 9362579 TI - What do surveyors need to track outcomes and compliance? AB - Sections 1819 and 1919 of the Social Security Act provide the statutory basis for the federal regulations identifying requirements long-term-care facilities must meet in caring for residents with pressure ulcers. Crucial to those requirements are the concepts of "highest practicable," "each resident", and "professional standards of quality." Combined with the requirements for a standardized assessment and care plan, these concepts form the basis for survey procedures and interpretive guidelines that systematically review information needed to determine compliance with the requirements at 42 Code of Federal Regulations, section 483.25(c)(1)(2). PMID- 9362580 TI - Liability under the False Claims Act for inadequate care of nursing facility residents. AB - The False Claims Act (FCA) was invoked recently to sue the owners of a long-term care facility for inadequate care of facility residents. The theory is simple: Medicare and Medicaid provider certification agreements require compliance with all federal and state laws applicable to the services provided. Submitting claims for reimbursement while providing inadequate care and, thus, failing to comply with the extensive nursing home quality-of-care federal and state laws, constitutes fraud on the government, actionable under the FCA. No court considered the government's theory in this case, as parties settled early in the litigation. Nevertheless, owners of facilities should not expect to rely on written patient records and case notes to avoid liability for false claims if the records are inconsistent with the physical condition of the residents. PMID- 9362581 TI - Management of pressure ulcers in long-term care. AB - Regulations governing long-term care and the associated potential for litigation make pressure ulcer management an important issue for long-term-care facilities. In response, many facilities have developed dedicated wound care programs to care for the increasing number of residents with pressure ulcers. These programs promote an enhanced awareness among the staff and instill preventive measures as part of the daily routine. To monitor pressure ulcer healing efficiently, staff at long-term-care facilities need: clear definitions of parameters that indicate healing and readily available, disposable tools for measuring these parameters simple, easily completed documentation forms that link treatment interventions and outcomes and meet regulatory requirements coordination of data and forms between multiple sites through a clearinghouse, allowing all participants to learn from the experiences of the whole. PMID- 9362582 TI - Monitoring wound healing in the home health arena. AB - To determine the type and quality of documentation in home health care agencies in the United States, a 15-question survey was sent to 500 agencies. The returned surveys revealed the following: (1) narrative notes were the most consistently used documentation tool; (2) 74% of agencies take photographs of the wound as part of their documentation; (3) 87% of agencies stage pressure ulcers according to the National Pressure Ulcer Advisory Panel (NPUAP) staging system; (4) 7% use reverse staging to document improvement in wounds; (5) 32% use standard protocols to treat different types of wounds; (6) 96% to 98% monitored healing by measuring length times width, as well as drainage and wound bed changes. The results indicate that most home health care agencies use the NPUAP staging system but do not track healing in a consistent way. They do not follow a consistent documentation standard, nor do their wound assessments bring together all the monitored factors indicative of healing progress. PMID- 9362583 TI - What is needed to monitor healing in the outpatient clinic setting? AB - To monitor healing in the outpatient setting, clinicians need: easily usable tools to collect data, whether a checklist or software program real-time analysis (or at least timely analysis) of the data relative to a treatment protocol a method of analysis that allows manipulation of the data for multiple purposes communication of the analysis; future actions should be based on this analysis. The result will be a dynamic, cyclical monitoring system, most meaningful when it is not retrospective and static, but fluid so that adjustments can be made as needed. PMID- 9362584 TI - The Pressure Sore Status Tool a few thousand assessments later. AB - Although the Pressure Sore Status Tool (PSST) was developed using expert panelists and its reliability has been previously reported, the patterns that seem to be forming based on the first few thousand PSST assessments have not been reported yet. This paper will focus on analyses of a subset of PSST assessments that were collected as a by-product of testing a computerized assessment and decision support system. Changes in wound characteristics that appear to serve as "lead indicators" of healing, preliminary factor analysis data, and a correlation of total PSST scores with recorded stage will be discussed. Due to the sample size and variability within the data, it is premature to draw firm conclusions from the data. However, analyses of the first few thousand assessments and over 100 healed pressure ulcers show promise in confirming some prior speculations about wound healing. The data also appear to suggest the possibility of surprises that are not necessarily part of current understanding of wound healing in pressure ulcers. PMID- 9362585 TI - Utility of the Sussman Wound Healing Tool in predicting wound healing outcomes in physical therapy. PMID- 9362586 TI - The Sessing Scale for measurement of pressure ulcer healing. AB - Measurement of healing is an essential aspect of pressure ulcer management. This paper provides a review of the Sessing Scale for measurement of pressure ulcer healing. The Sessing Scale is a seven-point observational scale anchored by verbal descriptions of wound healing. It is a simple, easy-to-use instrument with demonstrated validity and reliability for the measurement of healing. Findings indicate that with descriptions of granulation tissue, infection, necrosis, and eschar, the instrument measures an important domain of healing independent of wound size or depth. PMID- 9362587 TI - Wound Healing Scale, version 1.0: a proposal. AB - The Wound Healing Scale is a user-friendly, descriptive scale for assessing healing in all types of wounds, both acute and chronic. The scale consists of eight alphabetic modifiers that can be combined with the score from a number of different existing scales that assess wounding. The WHS can be utilized with large and small data sets and resolves the problem of reverse staging posed by regular reassessments using the Health Care Financing Administration's Minimum Data Set, version 2.0. PMID- 9362588 TI - Existing tools: are they meeting the challenges of pressure ulcer healing? AB - The measure of a chronic wound's progress (or lack of progress) toward healing is difficult. An instrument designed to measure healing in pressure ulcers must conform to two statistical concepts: validity and reliability. Existing tools are examined, based on this conceptual statistical framework. A model for the perfect wound healing instrument can be described. PMID- 9362589 TI - Presenting a draft pressure ulcer scale to monitor healing. AB - The PUSH Tool, a scientifically derived and validated tool for measuring and monitoring pressure ulcer healing, has been introduced. Input has been received from a multidisciplinary audience of participants in a collegial atmosphere conducive to the exchange of ideas. The audience represented many different care settings and included clinicians, educators, researchers, and policy makers. Steps have begun to refine the characteristics and utility of the PUSH Tool. The PUSH Task Force will continue a validation and development process that will include participation from the wound care community. PMID- 9362590 TI - Using principal component analysis to describe wound status. AB - Principal component (PC) analysis was used to assess the status of pressure ulcers over time in 37 subjects. Content validity was established by literature review and expert opinion. The primary variables in the wound healing model are ulcer surface area, exudate amount, and surface appearance. A linear function based on PC analysis of these values was established at each time point with an appropriate weighting of 2:3:3. This function explained 55% to 65% of the variation in the data. Other variables were considered in the model as well. However, because of the correlation of these variables with the original three, the modeling was not improved. A decreasing function from week 0 to week 8 established a good linear fit to the data and reasonable discrimination between time points, given the limitations of the sample size. There is good discrimination among the time points, at least for the earlier times compared with the later times. The procedure, although promising, requires validation with a larger data set. PMID- 9362591 TI - Pressure ulcer scale for healing: derivation and validation of the PUSH tool. The PUSH Task Force. AB - Measuring progress toward healing is fundamental to the management of pressure ulcers. A method to assess progress of an individual ulcer over time is lacking. Given the limitations of currently available instruments and the need for a precise and practical method of monitoring healing in clinical practice, the National Pressure Ulcer Advisory Panel initiated the development of a new tool for measuring pressure ulcer healing. The key elements in developing an instrument include simplicity of use in clinical settings, validity for measuring whether ulcers are improving or worsening, and sensitivity to changes in the ulcer between observations. A new tool incorporating surface area, exudate amount, and surface appearance is proposed. Content validity, correlation validity, prospective validity, and sensitivity to change can be met by the proposed Pressure Ulcer Scale for Healing instrument. PMID- 9362592 TI - PUSH Tool reality check: audience response. Pressure Ulcer Scale for Healing. AB - Following presentation of the Pressure Ulcer Scale for Healing (PUSH), conference participants broke into small discussion groups according to their practice settings: acute care, long-term care, and home care/outpatient care. Questions were posed to participants regarding the reality of using the PUSH Tool in their practice settings. These questions were structured to elicit comments about: (1) the characteristics of the PUSH Tool; (2) the validity, reliability, and practicality of the PUSH Tool; and (3) education and implementation requirements prior to use of the PUSH Tool. This article summarizes their comments, which will be used in refining the PUSH Tool. PMID- 9362593 TI - Revision of the PUSH Tool using an expanded database. Pressure Ulcer Scale for Healing. AB - The National Pressure Ulcer Advisory Panel's Pressure Ulcer Scale for Healing has been introduced and is undergoing retrospective refinement through testing on a larger data set. Sites for the National Demonstration Project, a prospective study, are being sought. PMID- 9362594 TI - Education, self-care, and outcomes of rheumatic diseases: further challenges to the "biomedical model" paradigm. PMID- 9362595 TI - Comparison of general internists, family physicians, and rheumatologists managing patients with symptoms of osteoarthritis of the knee. AB - OBJECTIVE: To evaluate the nature, risks, and benefits of osteoarthritis (OA) management by primary care physicians and rheumatologists. METHODS: Subjects were 419 patients followed for symptoms of knee OA by either a specialist in family medicine (FM) or general internal medicine (GIM) or by a rheumatologist (RH). Management practices were characterized by in-home documentation by a visiting nurse of drugs taken to relieve OA pain or to prevent gastrointestinal side effects of nonsteroidal anti-inflammatory drugs (NSAIDs) and by patient report (self-administered survey) of nonpharmacologic treatments. Changes in outcomes (knee pain and physical function) over 6 months were measured with the Western Ontario and McMaster Universities Osteoarthritis Index. RESULTS: Patients of RHs were 2-3 years older (P = 0.035) and tended to exhibit greater radiographic severity of OA (P = 0.064) and poorer physical function (P = 0.076) at baseline than the other 2 groups. In all 3 groups, knee pain and physical function improved slightly over 6 months; however, between-group differences were not significant. Compared to drug management of knee pain by FMs or RHs, that by the GIMs was distinguished by greater utilization of acetaminophen and nonacetylated salicylates (P = 0.008), lower prescribed doses of NSAIDs (P = 0.007), and, therefore, lower risk of iatrogenic gastroenteropathy (P < 0.001). In contrast, patients of RHs were more likely than those of FMs and GIMs to report that they had been instructed in use of isometric quadriceps and range-of-motion exercises (P < or = 0.001), application of heat (P = 0.051) and cold (P < 0.001) packs, and in the principles of joint protection (P = 0.016). Neither physician specialty nor specific management practices accounted for variations in patient outcomes. CONCLUSION: This observational study identified specialty-related variability in key aspects of the management of knee OA in the community (i.e., frequency and dosing of NSAIDs, use of nonpharmacologic modalities) that bear strong implications for long-term safety and cost. However, changes in knee pain and function over 6 months were unrelated to variations in management practices. PMID- 9362596 TI - In vivo hip pressures during cane and load-carrying gait. AB - OBJECTIVE: To test the hypotheses that carrying a load reduces hip contact pressure ipsilateral to the load and that using a cane when carrying a load further reduces hip contact pressure. METHODS: A Moore-type endoprosthesis with 13 femoral-head pressure transducers was implanted in a human subject following a Garden III fracture. Hip contact pressures were measured during unaided, cane aided, and load-carrying gait over two years. RESULTS: Relative to unloaded gait, contact pressures increased significantly when ipsilateral to the carried load. Using a contralateral cane when carrying the load reduced ipsilateral posterior superior contact pressure; however, the hip contralateral to the load experienced significantly higher than normal pressures. CONCLUSIONS: Ipsilaterally carried loads may not always provide stress protection of the arthritic hip. Using a cane opposite to the load may aid in restoring normal pressures to the ipsilateral hip, but may expose the contralateral hip to a significant stress burden. PMID- 9362597 TI - Acetabular pressures during hip arthritis exercises. AB - OBJECTIVE: To examine in vivo maximum acetabular contact pressures during gait and hip arthritis exercises recommended by clinicians and the Arthritis Foundation. METHODS: Acetabular contact pressure data were collected for 2.5 years, at 3-4-month intervals, from an instrumented endoprosthesis implanted in an 84-year-old male who had sustained a left hip fracture. Maximum pressure data were compared for each activity. RESULTS: Mean pressures ranged from 9.0 +/- 2.3 megapascals (MPa) during maximum isometric hip abduction, 9.0 +/- 0.8 MPa during standing right hip abduction, and 8.9 +/- 2.8 MPa during standing left hip abduction to 1.2 +/- 0.3 MPa during quiet standing. Free-speed gait pressure averaged 5.6 +/- 0.9 MPa. The maximum mean pressure during side-lying hip abduction and straight leg raise at 30 degrees/second were less than the same activities at 60 degrees/second. CONCLUSIONS: These in vivo hip pressure measurements challenge traditional protocols for patients with hip osteoarthritis and provide quantitative data as a framework for designing exercise programs. Maximum isometric hip exercise and standing exercise generated much higher hip pressures, and are therefore probably more stressful to acetabular cartilage, than gait or stationary cycling. Clinicians must consider exercise velocity because of its direct correlation with hip contact pressure. Walking generated lower pressure than most activities studied and, given its other benefits, is therefore probably beneficial for patients with hip osteoarthritis. PMID- 9362598 TI - Patient education and disease activity: a study among rheumatoid arthritis patients. AB - OBJECTIVE: To determine whether patients experiencing high disease activity derive more benefit from patient education than those experiencing low disease activity. METHODS: Data from a randomized study on the effects of a program of patient education were analyzed retrospectively. Four subgroups were studied: the high disease activity subgroup of patients who had participated in the educational program, the complementary low disease activity subgroup, the high disease activity subgroup of controls, and its low disease activity complement. Patients with erythrocyte sedimentation rate > 28 mm/first hour were classified as having high disease activity. Effects on frequency of physical exercises, endurance exercises, and relaxation exercises and effects on health status (Modified Health Assessment Questionnaire, Dutch Arthritis Impact Measurement Scales [AIMS]) were measured. RESULTS: There were no significant differences between the adherence parameters of the various pairs of groups. Four months after the educational program began, anxiety and depression scores on the Dutch AIMS had increased among participating patients who were experiencing high disease activity and decreased among those who were experiencing low disease activity. CONCLUSIONS: Patients experiencing high disease activity did not derive more benefit from patient education than those experiencing low disease activity. On the contrary, an increase of anxiety and depression is found in these patients. Further study is needed to confirm our findings. PMID- 9362599 TI - A problem-based education program for patients with rheumatoid arthritis: evaluation after three and twelve months. AB - OBJECTIVE: To develop and evaluate the effect of a new arthritis education program based on a previous study. METHODS: One hundred individuals with established rheumatoid arthritis randomized to an intervention group or a control group completed self-report questionnaires. RESULTS: Three months after the education program the patients in the intervention group had increased their knowledge about their disease. They reported increased practice of exercise and joint protection and reduction of disability and pain. After 12 months, increased knowledge and practice of joint protection was maintained. However, there was no longer any difference between the intervention group and the control group regarding reported pain, disability, and practice of exercise. At both intervals the individuals in the intervention group reported an increased ability to handle their pain and a reduction of problems with their disease. The control group remained stable except for a slight increase in pain. CONCLUSION: A structured patient education program had positive impact for 3 months, and some improvements were maintained for 12 months. We suggest that patient education should become an integrated part of the total management of rheumatoid arthritis. PMID- 9362600 TI - Mixed connective tissue disease. PMID- 9362601 TI - Determining the cost of a clinical intervention through the use of shadow pricing. PMID- 9362602 TI - Shifting toward systems of healing. PMID- 9362603 TI - Sentinel event review, Part II: A new spirit of inquiry. PMID- 9362604 TI - Food for thought. PMID- 9362605 TI - Can you create a professional practice model in a unionized setting? PMID- 9362606 TI - 'Do it for the nurses'--resource allocation under devolved management structures. PMID- 9362607 TI - Issues of death and dying: the perspective of critical care nurses. AB - A major shift in the care of terminally ill people, due to advances in technology, and the development of legislation regarding patient self determination and autonomy, has occurred over recent years. Critical care nurses (CCNs) are involved daily in issues of death and dying and are very aware of the needs, fears and psychosocial issues of patients and their families. Professional associations see a legitimate role for nurses in assisting the dying to achieve a dignified death. For legislation, policies and guidelines surrounding end-of-life issues to be effective, and to assist nursing staff with these sensitive, often difficult concerns, it is important that data on the opinions and perspectives of CCNs be objectively obtained. In a study by the Department of Social and Preventive Medicine at the University of Queensland, questionnaires were sent to 1100 randomly sampled community members and almost 1200 health professionals (nurses, general practitioners and specialists), including 299 CCNs. The response rate of CCNs to a 30-page postal questionnaire was 79 per cent (n = 231), indicating those nurses' high levels of interest in and/or concern regarding this area. CCNs supported the use of advance directives, the appointment of proxies and the need for doctors and nurses to give sufficient medication to relieve pain, even if this hastened the death of the patient. In addition, CCNs, more than any other professional group, supported the right of the terminally ill patient to physician-assisted suicide or euthanasia, their responses being very similar to those of community members. CCNs clearly face issues which, from legal, medical and ethical viewpoints, cause them concern. In sharing their personal experiences, CCNs stressed the need for more communication between doctors and patients, as well as between doctors and nurses. In addition, CCNs saw a clear role for themselves as advocates for patients/families in the decision-making process. PMID- 9362608 TI - Chest X-ray quiz. Complete left lung atelectasis. PMID- 9362609 TI - Sedation of adult critically ill ventilated patients in intensive care units: a national survey. AB - The aim of this survey was to review the practice of sedation for adult artificially ventilated patients in Australian intensive care units. In particular, the survey sought to investigate the drugs used, how they were administered, who was responsible for the administration, how sedation was assessed, and if, in the opinion of charge nurses, complications were occurring as a result of their practice. Questionnaires were sent by post to the clinical nurse consultants (CNCs) in charge of 72 units containing five or more beds, as identified in the Hospital Health Services Yearbook. By June 1996, 65 questionnaires had been returned (a 90 per cent response rate). Results showed that the most common form of sedation is a combination of benzodiazepines and narcotics (88 per cent); in particular, morphia (92 per cent) and midazolam (94 per cent). In 79 per cent of units, these drugs are administered by continuous infusion. Neuromuscular blocking agents are no longer commonly used in conjunction with sedation, with the majority of units (88 per cent) indicating occasional use only. Also in the majority of units (94 per cent), nurses are responsible for titrating and administering sedation. The experience of these nurses varied; in 61 per cent of units it ranged from first year post-graduation to the holding of a critical care certificate. In most units (63 per cent), the aim is to lightly sedate patients. Methods of assessing sedation vary, with few units using sedation scales (17 per cent). Twenty six CNCs (40 per cent) reported that, in their opinion, there were no complications related to their practice of sedation. The most common complication reported (by 21 CNCs or 32 per cent) was over-sedation. It appears that there is no consistent method of assessing the level of sedation in critically ill ventilated patients and that over-sedation is common. Therefore, it is recommended that clinicians investigate the possibility of introducing sedation scales in their units. However, the efficacy of such scales in ensuring a more appropriate level of sedation needs to be researched. PMID- 9362610 TI - Internet--information super-highway. PMID- 9362611 TI - A report on the 'National Review of Specialist Nurse Education'. PMID- 9362612 TI - UHC operations improvement: adult ICU benchmarking project summary. University HealthSystem Consortium. AB - The editors are providing this Executive Summary by the University HealthSystem Consortium of their Adult ICU Benchmarking Project. The report has been reviewed by the participating members listed at the end of the summary. The summary report provides both an interesting account of how a benchmarking project of considerable magnitude can be accomplished but also indicates how important comparative data can be used to improve individual programs. PMID- 9362613 TI - Benchmarking for best practice in critical care medicine: can it realistically be done? AB - An individual program's viewpoint on the overall benchmarking process for critical care medicine and how this process can provide a conceptual understanding of how benchmarking can be beneficial. PMID- 9362614 TI - The impact of managed care on hospital nursing. AB - There is a significant but different role for hospital staff nurses within a managed care environment. This article describes the role and reviews major areas where the staff nurse is critical in achieving positive patient outcomes that are cost-effective and efficient. PMID- 9362615 TI - Benchmarking retirement: a best practices decision. AB - Making the decision to retire from active practice is a complex process with very strong psychological overtones. Successful retirement demands preplanning, and financial preplanning must begin very early in the career to achieve the time value of money. Psychological preparation requires recognition that retirement is inevitable, and an avenue of change for yourself and your spouse should be identified, anticipated, and refined over time. PMID- 9362616 TI - Standardized patients: a new method to assess the clinical skills of physicians. AB - A growing concern about the deterioration of the clinical skills of physicians has stimulated a renewed interest in the teaching and assessment of these skills. Standardized patients can be an effective means to teach or assess a physician's competence in clinical skills, such as history taking, physical examination, and patient-physician interaction skills. This article will describe this new method and delineate its emerging role in medical school education, residency training, and its potential role in continuing education and quality assurance for practicing physicians within a managed care setting. PMID- 9362617 TI - Opportunities for potential cost saving in the management of acute myocardial infarction. AB - BACKGROUND: The total expense associated with acute myocardial infarction in the United States is substantial because of the combination of high volume and high cost per case. The aim of this study was to identify potential cost-saving strategies for the management of acute myocardial infarction. METHODS: Information was gathered through professional interviews combined with an extensive literature review. RESULTS: Numerous opportunities for cost savings were identified and classified into six categories: pharmaceuticals, changing the work within steps, corporate philosophy and clinical decision making, continuous physician education and involvement, preventive measures and systems of care, and additional resources. CONCLUSIONS: Although there are many possible areas healthcare providers could consider for cost saving in acute myocardial infarction, the situation at each site will need to be considered carefully before areas are selected. It is of vital importance that the quality of care not be compromised in the effort to reduce cost. PMID- 9362618 TI - What makes a nurse competent to prescribe? PMID- 9362619 TI - Should we reshape nurse education yet again? PMID- 9362620 TI - Notes on the pathogenesis of serious pressure sores. AB - It is often assumed that pressure sores are caused by the flattening of blood capillaries, resulting in tissue ischaemia. However, the available evidence, especially that from animal experiments, indicates that microvascular trauma has a significant part to play. Published curves showing the relationship between level of pressure and duration of application also show that simple ischaemia is an inadequate explanation of pressure sore pathogenesis. The crucial pressure (tissue pressure) is normally estimated from interface pressure measurements. However, the relationship between tissue pressure and interface pressure is more complex than is generally realized. Other factors, such as shearing and static friction, are discussed briefly, and recommendations are made for clinical practice and further research. PMID- 9362621 TI - Perceptions of environmental stressors in the neonatal unit. AB - The purpose of this study was to explore maternal and infant stress within the neonatal intensive care unit (NICU) environment and to assess the perceptions of neonatal nurses in relation to these stressors. Using both qualitative and quantitative methods, 12 mothers and 12 nurses were interviewed. Within the framework of the Roy Adaptation Model, the interview schedules were structured to include an 18-item stress scale. Results reflected a lower maternal stress level than was perceived by nurses, with mothers of very low birthweight babies reporting higher stress levels than mothers of low birthweight babies. Nurses' perceptions of the elements of the environment that caused most maternal stress differed from those reported by mothers. The highest reported stressor in the maternal group was the heat intensity; however, the nursing sample perceived the highest maternal stressor to be the monitors attached to the baby. This study highlights the need for increased awareness of stress in both the technological and psychosocial environment of the NICU. The promotion of individualized developmental care is also emphasized, with the aim of modifying and controlling environmental stress for both the mother and the neonate. PMID- 9362622 TI - Formulating a risk management strategy. PMID- 9362623 TI - Is advanced nursing practice a post or a person? AB - While the nursing profession is making progress in clarifying its position within the healthcare setting, the recent proliferation of now nursing roles is potentially clouding the issue. Roles such as expert practitioner, advanced practitioner and specialist practitioner are not clearly defined which causes confusion both within and out with the profession. In the UK, the nursing profession's educational and national registration bodies have been struggling to develop a consensus on what these roles should entail and what part education should play in their development. The latest definitive position statement from the UKCC states that there are 'neither agreed definitions of advanced practice nor criteria against which standards can be set' (UKCC, 1997a). It is, therefore, proposed that the profession re-examines the use of the term 'advanced nursing practice' and accepts that this term describes characteristics that are not dependent on academic levels of education. PMID- 9362624 TI - Advanced nursing practice in the USA: new directions for NPs. AB - The demand for nurse practitioners (NPs) continues to increase in the USA and, as a result, the NP role is expanding. Originally, NPs were primarily based in the primary care arena; however, they are now filtering into secondary and tertiary healthcare settings, bringing with them advanced clinical skills. This has led to many clinical nurse specialists undertaking NP programmes. American nurses are now calling for a merger of these two roles and for changes in NP training programmes that will prepare practitioners for work in secondary and tertiary care environments as well as primary care settings. British nurses continue to examine the perimeters of advanced nursing practice; however, the realms of secondary and tertiary care should not be neglected, but rather incorporated into these developing roles and educational preparations. PMID- 9362625 TI - Just 'doing the observations': reflective practice in nursing. AB - The first part of this article explores the development, definition, and design of reflective practice. In the second part the author relates an 'ordinary nursing' story--'10 minutes with Mr Kandinski'--and uses an existentialist framework for reflective analysis. Reflection on personal experience can expose something of the interrelationship of theory and practice, perhaps helping practitioners to improve their work. More importantly, reflective practice provides a means for nurses to reveal a more complete picture of the reality of nursing work to others. PMID- 9362626 TI - Nurse occupational stress research 3: a model of stress for research. AB - The second article in this series (Vol 6(12):710-13) explored definitions of stress and emphasized the need for suitable models of nurse stress for research purposes. This article, the third in the series, examines models of stress, and identifies those which may be suitable for future nurse stress research. The author's model of nurse stress for use in carrying out research and stress management is outlined and discussed. PMID- 9362628 TI - Lessons to be learned from a nation in mourning. PMID- 9362627 TI - The Vicair Academy and Liberty range of pressure-reducing seating. AB - Many patients can be sitting in a chair for between 3 and 14 hours each day, consequently the type of cushion they are sitting on is of the utmost importance. These patients are often at high risk of developing pressure sores--possibly more so than bed-bound patients. Vicair, whose UK distributor is Gerald Simonds Healthcare, has developed two types of pressure-reducing cushions: the Vicair Academy and Liberty Fluid-Air. These cushions offer pressure reduction in a system that is user-friendly and particularly lightweight. This product focus highlights the problems associated with seating and explains how the Vicair range of cushions attempts to address them. PMID- 9362629 TI - Different government: improved pay award? PMID- 9362630 TI - Qualitative research in nursing: a quest for quality. PMID- 9362631 TI - Lower limb amputation. 1: indications and treatment. AB - Lower limb amputation is performed predominantly to alleviate acute and chronic limb ischaemia caused by vascular disease, poorly controlled diabetes or, occasionally, infection. Atherosclerosis is the primary cause of chronic arterial ischaemia and the most common reason for amputation. The vascular nurse has an important role in reducing the need for amputation, by providing information on health promotion and illness prevention to patients with vascular insufficiency to halt progression to amputation. This is the first of four articles focusing on lower limb amputation. It examines the indications for lower limb amputation in detail, and briefly outlines other treatment options including revascularization techniques. PMID- 9362632 TI - Taking a sexual health history: the role of the practice nurse. AB - Nurses working in general practice (GP) settings are generally multiskilled and competent practitioners who come into contact with a huge cross-section of patients. These patients frequently present with a combination of health problems/needs. The practice nurse is often the first person with whom the patient comes into contact and/or consults. Practice nurses therefore have an important role to play in promoting health, including sexual health. This article examines the conclusions of Jewitt's (1995) work which explored the development of sexual history taking in GP settings. The pivotal role of the practice nurse is highlighted and the importance of taking a sexual health history is discussed. The obstacles and barriers faced by practice nurses when taking a sexual health history are outlined. Recommendations for practice are discussed, and a check list is presented that will enable practice nurses to consider their invaluable input into the holistic care of patients in more detail. PMID- 9362633 TI - Use of EMDR to treat morbid jealousy: a case study. AB - Eye movement desensitization and reprocessing (EMDR) is a relatively new psychological intervention which has mainly been utilized to treat post-traumatic stress disorder symptoms. The following case study of a 75-year-old World War II veteran, however, illustrates that such symptoms can present in less obvious ways. During his incarceration, the soldier had been subjected to systematic taunting by his Japanese captives. The resultant traumatic memories had been triggered in a range of social situations over the next 50 years, leaving a legacy of morbid jealousy which was quickly and effectively treated. Potential areas for research are indicated. PMID- 9362634 TI - Venous leg ulcers: short-stretch bandage compression therapy. AB - Graduated compression therapy is rapidly becoming the treatment of choice for venous leg ulcers; it is cost-effective and offers faster healing rates than without compression. Holistic assessment of the patient along with education of the practitioner leads to the safe application of compression bandages. This article looks at the assessment of venous ulcers and how application of short stretch bandages can achieve graduated compression, leading to rapid healing. As with any new skill, compression bandaging requires the practitioner to have received research-based education and practice and to have a clear understanding of how the technique achieves the objective. PMID- 9362635 TI - Dressing selection: use of combinations of wound dressings. AB - There are many wound dressing products available. In certain circumstances they are used in combination. In order to protect the patient, the use of dressing combinations should have a clear purpose and the support of the manufactures. Inappropriate combinations are costly and ineffective and serve only to perpetuate practice that does not have a sound research base. This article highlights the issues surrounding dressing selection and offers guidance on appropriate dressing combinations. PMID- 9362636 TI - Interdisciplinary teamwork: consideration of the challenges. AB - Most services currently provided by the NHS involve a considerable amount of interdisciplinary team working. The effectiveness of team structures and team functioning is variable, ranging from effective to fragmented service coordination. Despite major developments in establishing productive multidisciplinary team working over the past decade, several key challenges still need to be overcome. This article outlines a definition of and the rationale for successful interdisciplinary teamwork. It considers key organizational, professional and interpersonal challenges that need to be addressed if the present level of teamwork is to be enhanced. PMID- 9362638 TI - Impact of Dearing on the future of nurse education. PMID- 9362637 TI - Expanded role of the nurse: accountability confusion. AB - Nurses are increasingly taking over the clinical activities once carried out by doctors. In some areas it has now become difficult to distinguish the boundaries between nursing and medical health care. These changes raise important legal issues which will need to be considered by a court when dealing with clinical negligence cases involving the expanded role of the nurse. PMID- 9362639 TI - You're so clever--you should be a doctor! PMID- 9362640 TI - Female circumcision genital mutilation and childbirth--a mother and child tragedy. PMID- 9362641 TI - Operating department staffing--a business manager's perspective. PMID- 9362642 TI - Termination of pregnancy--a nurse's right to choose. AB - If the conflict between pro- and anti-abortionists in nursing persists, perhaps a solution might be the establishment of specialised treatment centres designed specifically for termination procedures. Staff in these centres could be selected on the basis of their suitability and empathy with the women in their care. However, the establishment of such centres would fall into the category of an ideal solution and are highly unlikely to be adopted in practice. It is the responsibility of every nurse to clarify in their own mind exactly where they stand on such issues as termination of pregnancy before they accept a post where such procedures are likely to be carried out. Once a nurse has committed his or herself to assisting in theatre, then they should be prepared to collaborate fully with the work of the surgical team. Education can ensure that nurses are aware of all the issues and are able to make their own decision based on real experience. Abortions will always be carried out whether inside or outside the law; it is far better that women receive the best possible care and counselling and it is the duty of the nursing profession to provide that care. PMID- 9362643 TI - Pain in the elderly. PMID- 9362644 TI - NATN on the web--how to get there! PMID- 9362645 TI - This is ... the UKCC. PMID- 9362646 TI - Sacred cows and sound practice. PMID- 9362648 TI - That was then. This is now. PMID- 9362647 TI - The design and introduction of videos and leaflets. AB - This article describes how the staff within the theatre department at Neath General Hospital, Glan-y-Mor NHS Trust, South Wales, developed patient information videos and leaflets for adults and children which will be used to support their pre-operative visiting programme. PMID- 9362649 TI - Genetic research: every nurse's new frontier. PMID- 9362650 TI - A family affected by mitochondrial encephalomyopathy: a nursing protocol. AB - Mitochondrial encephalomyopathies are rare genetic diseases that affect organs and tissues with high oxidative activity, such as the brain, striated muscles, and heart. Although these conditions have received attention in the medical literature, there is an absence of published information on this topic in the nursing literature. The purpose of this article is twofold: (1) to provide an overview of mitochondrial encephalomyopathies and (2) to present a protocol to guide nursing practice. Protocol development is based on a case history and guided by Dungan's model of dynamic integration. The protocol addresses perceived family needs, nursing interventions, and outcomes of care. PMID- 9362651 TI - The transformative effects of illness. AB - In "The Soft Core" Arturo Vivante examines the bonds between a middle-aged son and his aging father. Years of habit that had solidified into accustomed but uncomfortable ways of behaving and interacting with each other are altered when the father's stroke evokes a tumultuous range of emotions in the son, leading him, in the end, to feel compassion, not just for his father but also for himself. Vivante shows the reader that illness has the ability to transform an individual who is willing to reexamine and reevaluate the meaning he or she gives to life. This process, however, is not an easy one, as it is often undertaken as in the story, when the individual fears the death of self or of a loved one. The suffering, though, can transform. The self-awareness gained leads to a more gentler way of being, and compassion results. This compassion is borne of understanding, recognition, and appreciation that the frailties of human nature exist in each of us. Recognizing and applying this to all manner of relationships in our lives is the wisdom that compassion gives to our existence. PMID- 9362652 TI - An international look at expert nursing practice. PMID- 9362653 TI - Barriers and facilitators to the utilization of nursing research. AB - The nurse in clinical practice must demonstrate a scientific base for practice grounded in research findings. The purpose of this study was to explore the nurse's perception of the barriers and facilitators to using research findings in nursing practice. A survey methodology was used, and a sample of 356 practicing registered nurses responded. Data were collected using a scale that rated the barriers and facilitators to research utilization. The greatest barriers were insufficient time on the job to implement new ideas, lack of knowledge of nursing research findings, and inaccessibility of relevant literature. The advanced practice nurse is in a pivotal position to decrease the barriers to research utilization. PMID- 9362654 TI - The challenges of clinical nursing research: strategies for successful conduct. AB - Although the literature is replete with stringent methodological guidelines for designing experimental and quasi-experimental studies, there is a paucity of literature addressing the challenges of conducting these studies in the "real world" of the clinical setting. This article describes the challenges experienced by a team of researchers conducting a study in the acute care setting, including those associated with navigating organizational restructuring and managing within a climate of uncertainty. The study focused on the evaluation of a nurse delivered smoking cessation intervention for hospitalized cardiac patients. As each particular challenge emerged, strategies were developed. By explicating these challenges and strategies, we hope to help clinical researchers deal with challenges proactively rather than reactively. PMID- 9362655 TI - Determining and discerning expert practice: a review of the literature. AB - Although the nature and characteristics of expert practice have been described in the literature, the description is incomplete. How expertise is gained is not fully understood, and definitions of expert competencies have yet to be developed. Essential issues for education arise from the demand for knowledge for expert practice. Because expertise is gained in the context of practice, expertise cannot be achieved out of context or taught as an academic exercise. A clear picture of the practice of expert nurses is necessary so that those in the profession can know and articulate expert practice and direct it to the community. PMID- 9362656 TI - Nursing of aggregates versus individuals. PMID- 9362657 TI - Caring for the community: development of the advanced practice nurse role. AB - In a collaborative effort with a large metropolitan hospital in Boston, a community assessment was conducted to determine ways in which an advanced practice nurse (APN) could enhance delivery to a nearby small urban community. The authors attended healthcare delivery meetings, interviewed community leaders, visited various community sites, and became familiar with the community and its residents. The assessment included evaluation with proposed intervention strategies, development of a model for enhancing delivery of care based on Orem's Self-Care Theory, and a role description for an APN that incorporated collaboration between the APN and the community health nurse. A community assessment enabled the APN to become a vital healthcare leader. PMID- 9362658 TI - States legislative and regulatory forum. PMID- 9362659 TI - To gain "new" knowledge. PMID- 9362660 TI - Nursing standard of practice protocol: depression in elderly patients. NICHE faculty. AB - Depression is a highly prevalent but underrecognized and undertreated mental health problem in community-dwelling, medically ill, and institutionalized older adults. Untreated depression is associated with serious negative consequences for the elderly patient. Nurses in various practice settings can reduce the negative effects of depression through early recognition, intervention, and referral of patients with depression. This article presents an overview of depression in late life with emphasis on age-related assessment considerations, clinical decision making, and nursing intervention strategies for elders with depression. A standard of practice protocol for use by nurses in a variety of practice settings is also presented. PMID- 9362661 TI - Perception of hearing loss and hearing handicap on hearing aid use by nursing home residents. AB - The purpose of this study was to examine the perception of hearing loss and self assessed hearing handicap on hearing aid use by nursing home residents. Sixty elderly individuals who had a hearing loss and wore hearing aids were given the Nursing Home Hearing Handicap Index and were asked specific questions related to hearing aid use. The overall results indicated that there was a moderate correlation among all three variables. It was determined that nursing home residents consistently use their hearing aids. However, amplification does not address all the communication needs of the nursing home resident. Assistive listening devices and environmental modification would improve communication ability and the quality of life of the nursing home resident. PMID- 9362662 TI - Care of the traumatized older adult. AB - Older adults are experiencing excellent health and maintaining active lifestyles. They continue to engage in the activities they have enjoyed throughout their lives, but as they grow older they are at increased risk for injury related to these activities. Older adults suffer injuries of equivalent severity as those of younger patients; however, the consequences are much more severe. The older adult presents a unique and complex scenario that requires nurses to understand the normal physiological changes of aging and the effects of chronic disease. This article provides guidelines for the emergency care of the older adult patient with trauma and emphasizes areas that require special considerations. PMID- 9362663 TI - Assessment of function: critically important to acute care of elders. The NICHE Faculty. AB - Assessment of functional status in hospitalized elders provides essential information that can assist maintenance or restoration of self-care. Nurses in acute care settings are in a pivotal position to assess function and target interventions to prevent loss of function and maintain an individual's self-care ability. This article discusses critical issues in the functional assessment of hospitalized elders and provides a clinical practice protocol that includes nursing care strategies to prevent functional decline during hospitalization and assist with discharge planning. PMID- 9362664 TI - A life care community from three perspectives. AB - Changing societal supports, family structures, and an increasing number of affluent elders have altered the caring giving and receiving patterns for many middle-aged and older adults in the United States. Life care communities have been available for several decades, but only in the last two decades have they begun to flourish. The following report exemplifies some of the benefits and the concerns encountered in a life care community. PMID- 9362665 TI - Mary Opal Wolanin: a life worth living ... a life of giving. Interview by Dianne Thomas. AB - This is the first of two articles related to the conversation that the board had with Mary Opal Wolanin that evening. In Part I, she tells of her life, education, and nursing and geriatric nursing experiences. In Part II, Mrs. Wolanin presents challenges to nurses and shares her dreams for the future of nursing. PMID- 9362666 TI - Memories of Mary Opal Wolanin: geriatric nurse, mentor, friend. PMID- 9362667 TI - Vitamin E--for elderly? PMID- 9362668 TI - Management of aged in home care with suicidal thoughts or potential for self harm. PMID- 9362669 TI - What's new in treating and preventing Alzheimer's disease. PMID- 9362670 TI - Pain management: it's easier than you think. PMID- 9362671 TI - Workplace violence: nurses respond to challenge. PMID- 9362672 TI - Parish nursing and home care. PMID- 9362675 TI - Caring for the patient with a gastrostomy/jejunostomy tube. AB - A gastrostomy or jejunostomy (G or J) tube is useful for feeding malnourished patients and is preferred to prolonged use of total parenteral nutrition. Because enteral feeding has become commonplace in both the hospital and home setting, it is vital that health care workers instruct caregivers on the treatment of individuals with G tubes and/or J tubes. Many problems can be prevented when caregivers know how to care for the patient and troubleshoot potential concerns. PMID- 9362674 TI - Common phobias. AB - Mrs. Brown, a 65-year-old woman, was terrified of being alone at night and suffered from nyctophobia. Her husband had been dead for several years, and her 40-year-old son lived in another state with his family. She often called him in the middle of the night in a state of panic, and he felt helpless about her situation. She lived in a senior housing community that never had any problems with crime. Nonetheless, she lived in a continual stage of anxiety. PMID- 9362673 TI - Assisted suicide for the terminally ill: why we must have a choice. AB - As someone who believes in assisted suicide (AS) for terminally ill patients, I find the American Nurses Association and National Hospice Organization's official opposition a cause of profound concern. One of the arguments used by these organizations is that the lack of good palliative care is a major reason people request aid in dying. The assumption is that symptoms can be controlled adequately at all times. To me, such beliefs represent an ideology of a certain kind of death--a good death--espoused in such statements. This essay is an opportunity to express a different reality. PMID- 9362676 TI - Ministry of healing: a unique nursing role. AB - "I had felt a deep calling for a long period while I was working on the cardiology floor in the local hospital," remarks Kathy Ford, RN. "When I happened to come across a picture of parish nurse ministries and, after a telephone conversation with one of the nurses who told me what parish nursing was all about, I just knew that was what I was supposed to be doing." PMID- 9362677 TI - Influenza--it's that time again. AB - Influenza virus infections regularly increase serious morbidity and mortality in the United States. From 1972 to 1985, between 10,000 and 40,000 deaths were attributed to influenza each year. More than 90% of these deaths were individuals 65 years or older. PMID- 9362678 TI - What is the role of the pharmacist in home care? AB - Pharmacists provide a wide range of medications, along with health and convalescent aids, for patients at home. Traditionally community pharmacists have been viewed as providers of prescription and nonprescription medications administered orally. Today pharmacists in community and hospital pharmacies across the country have expanded their services for the homebound patient and provide a variety of sophisticated products and services in the patient's home. PMID- 9362679 TI - Major Medicare changes for home health industry. PMID- 9362680 TI - Patient satisfaction with home care after early postpartum hospital discharge. AB - The purpose of this descriptive study was to measure patient satisfaction with home care after early postpartum discharge. A convenience sample of 126 insured women was used in this study. A 25-item questionnaire measured patient satisfaction. Selected demographics were analyzed. The results of this investigation found that 87.3% (n = 110) of the participants were satisfied with home care provided after early postpartum discharge. PMID- 9362681 TI - What is the condition? Popliteal venous thrombosis. PMID- 9362682 TI - Parish nursing. Opportunities in community health. AB - Health care trends during the past decade, such as managed care and reduced hospital length of stay, have made home health a growing opportunity for professional nurses. The shift of persons with chronic illness from institutions to homes and communities has required community level approaches to support these clients and their caregivers. Health and social problems, such as teen pregnancy, HIV infection, and violence, have resulted in health education and health promotion efforts that target vulnerable populations. At the same time, limits on resources and reimbursement have restricted service delivery in many communities, both for long-term care of the chronically ill and to support health education and promotion programs. PMID- 9362684 TI - Finding your way through performance measures. PMID- 9362683 TI - Constipation. Diagnosis and treatment. AB - Chronic constipation, the number one gastrointestinal complaint in the United States, is a serious condition that affects patient quality of life and accounts for the annual expenditure of millions of dollars by affected individuals, many of whom attempt to self-manage their condition. Because constipation has varied etiologies and treatment modes, it is imperative for the family nurse practitioner to know options for patients. Constipation complaints can indicate multiple diseases, and such patients can be among the most difficult diagnostic and therapeutic problems in clinical practice. Two of the primary care provider's duties to these patients are to educate them about bowel habits and to explain how different medications may either aid or exacerbate their symptoms. Constipation is a universal affliction of Western civilization. In the United States, this malady accounts for more than 2.5 million physician visits per year, is among the most frequent reasons for self-medication, and is particularly troublesome in the elderly population. Americans spend more than $725 million annually on over-the-counter (OTC) laxatives in an attempt to self-treat the most common gastrointestinal complaint in the country. PMID- 9362685 TI - The future of home care accreditation. PMID- 9362686 TI - Who are rehabilitation technology suppliers? PMID- 9362687 TI - [Women and depression]. PMID- 9362688 TI - [Nurses' awareness of female mental health]. PMID- 9362689 TI - [A husband-wife jointly participated labor and delivery model]. PMID- 9362690 TI - [Promotion of women's health from the traditional Chinese medicine perspective]. PMID- 9362691 TI - [Behavior change of a primipara with cesarean section during early postpartum period]. AB - The focus of this study was to understand the process of behavior change in a cesarean section primipara during her early postpartum period. The study was conducted by the field method with the researcher as the subject's primary nurse. Content analysis was employed to analyze and categorize the 6 sections of the behavioral process record, which were taken down in narrative form by the researcher during the nursing process. Three stages of behavior change were identified: (1) Lack of confidence and uncertainty about self care and newborn care. (2) Actively intending to explore and learn about self care and newborn care. (3) Adjusting caring methods and planning for the future. In this study, the researcher provided information and caring to the subject individually. It assisted the new mother in becoming a competent mother. PMID- 9362692 TI - [Informational needs and information-seeking behaviors of recently diagnosed HIV seropositive gay man]. AB - In recent years, substantial changes in doctor-patient relations and consumer oriented attitudes have occurred. Many patients need more information regarding their diagnosis and treatment for developing positive coping strategies to face their disease. This case report uses an informational needs theoretical framework to present the informational needs and information-seeking behaviors of a recently diagnosed HIV seropositive gay man. The data was collected through continuous contacts with the patient during October 1994 to January 1995. This report's findings indicated that need for information after diagnosis fall into eight categories of concern: process in hospitalization, physical symptoms related to HIV/AIDS, side effects of anti-viral drugs, death, insurance, future planning, self care and how to disclose to others. Information seeking behaviors included actively or passively gathering information, asking others' experience and counseling with caregiver. Non-judgmental and supportive attitudes were significant factors for reducing the effects of social stigmatization as an obstacle to the patient during the information seeking process. PMID- 9362693 TI - [Nursing experience of bladder function reconstruction in a patient with neobladder surgery]. PMID- 9362694 TI - [Prevention of infections related to intravascular pressure monitoring system]. PMID- 9362695 TI - [Sodium and water restriction in patients with congestive heart failure]. PMID- 9362696 TI - [The nursing field also requires sex education: discussion on how to avoid the influence of gender role stereotypes on male nursing students]. PMID- 9362697 TI - [Application and perspective issues of sexual counseling]. PMID- 9362698 TI - [Nursing management of urinary incontinence]. PMID- 9362699 TI - [The clinical application of forced expiration technique in patients with mucus hypersecretion]. PMID- 9362700 TI - [Nursing care of lung transplant patients]. PMID- 9362701 TI - [Heart transplantation and the nursing care of transplant patient]. PMID- 9362702 TI - New graduate nurse preceptor program. PMID- 9362703 TI - Todd Collins. Interview by Kimberly Allen. PMID- 9362704 TI - Patient Safety Act of 1997 (H.R. 1165). PMID- 9362705 TI - Questions & answers about database searching. AB - Bibliographic databases such as RNdex, CINAHL, and MEDLINE help you find current clinical practice information beyond what is available in textbooks and reference manuals. There are many options for accessing these information resources, including some that are convenient and affordable for students. By learning basic search principles and techniques for searching these databases, you can save yourself time and be more successful in locating the information you need. Important search skills include being able to identify the component parts of your search topic, locate relevant subject headings in a database thesaurus, and use logical connectors to combine topic components. The better your skills at searching for information, the easier your study and research assignments will be. The information seeking skills you learn now will be applicable in the future too, as information resources evolve and as your learning needs change. Developing competence in database searching will help prepare you for a rich life of learning as you pursue your career as a nursing professional. PMID- 9362706 TI - Juggling nursing school and family. PMID- 9362708 TI - Strategies for taking lecture notes. PMID- 9362707 TI - Top ten strategies for working with nursing instructors. PMID- 9362709 TI - A student returns to teach. PMID- 9362710 TI - 1997 publishers directory. Resource books for nursing students. PMID- 9362711 TI - A study in caring. PMID- 9362712 TI - Mental health beliefs, practices, and knowledge of Chinese American immigrant women. AB - The purpose of this study was to describe the mental health beliefs and practices of Chinese American immigrant women. A two-part design using both qualitative and quantitative techniques was employed. The first step utilized focus group (n = 14) and key informant (n = 2) interviews to discover the beliefs, practices, and knowledge about mental health of this population. Content analysis was used to examine and condense the qualitative data. After completion of the qualitative component, 72 women were recruited to complete a set of questionnaires, which included a demographic questionnaire, culture and work subscale, and the mental health portion of the Health Behavior Scale of the Survey of Chinese American Mental Health (NRCAAMH, 1993). Pearson product-moment correlations and regression analysis were used to analyze the quantitative data. Content analysis found that the cultural value placed on the avoidance of shame, pragmatism that results in the use of both Western and traditional Chinese practitioners and treatments, and the inadequacy of Western-type services to meet the needs of the Chinese American immigrant population act as barriers to utilization of these services. These results are cross-validated by the quantitative findings. The importance of culture in determining the pathway to care was supported by the finding that higher levels of acculturation are related to greater use of mental health services. PMID- 9362713 TI - Family interventions with "troubled" Mexican American teens: an extrapolation from a review of the literature. AB - This article discusses therapeutic guidelines for family interventions with troubled Mexican American (MA) teenagers based on reports informing on MA teens and MA families. The typical MA teenager does not exist, and little is known about the complex variations in this population. What is known about some groups of MA teens is alarming and significant enough to provide some direction for serving this population. Existing data regarding teen social class levels, school performance, substance abuse, pregnancy and parenthood, and suicide are presented. Because knowledge about MA families is essential to guide interventions with MA teens in distress, the known traditional MA family is described, and the troubles that confront some MA families today are included. Findings from family cohesion studies, including those not involving MA teens in particular, are summarized to lend support to the guidelines presented. Associations found between family cohesion and various physical and psychiatric problems are noted to support the importance of the concept of cohesion in working with troubled teenagers and their families. PMID- 9362714 TI - Resourcefulness, appraisals, and coping efforts of family caregivers. AB - Despite the large body of literature on caregiver stress, there has been a relative dearth of investigation of the experience of caregiving among African Americans. African Americans are currently the largest minority group in the United States and a rapidly growing segment of the American elderly population. Increasing evidence demonstrates the stressfulness of, as well as the variability in adaptation to, caregiving in this population. There are differences in individuals' psychological resources and coping with the caregiving experience, which to date are not well understood. This descriptive study examined similarities and differences in appraisals of behavior problems, resourcefulness, and coping efforts between 25 African American and 25 Anglo-American caregivers of relatives diagnosed with probable Alzheimer's disease. African American caregivers were found to have higher scores in resourcefulness than Anglo American caregivers, and they reported benign appraisal of disruptive behavior in the impaired elders. No differences were found in caregivers' coping efforts. PMID- 9362715 TI - Minority adolescent mothers who reported childhood sexual abuse and those who did not: perceptions of themselves and their relationships. AB - Perceptions of two groups of minority adolescent mothers (those who reported childhood sexual abuse and those who did not) were examined by analyzing their responses to four open-ended questions. Responses of sexually abused (SA) and non sexually abused (NSA) respondents were studied, and themes that emerged from the data were derived. The responses from the groups were compared, and major thematic differences between the two groups identified. Distinct differences between the SA (n = 51) and NSA groups (n = 60) were detected in their responses to questions that related to their perceptions of themselves, their sexuality, and their relationships with men. Both SA and NSA groups had positive feelings about being parents, although the SA group expressed feelings of anxiety about the safety of their children. PMID- 9362716 TI - The development of a nurse stress checklist from English to Chinese version. AB - Work stress has been identified as a relevant problem in the field of professional nursing. Many instruments measuring nurse work stress have already been developed in the United States. The Nurse Stress Checklist (NSC), a Likert type questionnaire with 47 items, was selected for adaptation into the Chinese language from among these instruments, following a literature review and a comparison with the author's personal nursing experiences. The processes of developing the validity of an NSC Chinese version--content validity, concurrent validity, and construct validity--were conducted. In this pilot study, 13 Chinese nurses who had previously worked in the United States and who were fluent in both Chinese and English filled out the NSC in both the Chinese and English versions. Pearson's correlation was performed to build up concurrent validity. Next, 138 Chinese nurses were randomly selected from three medical centers in Taiwan to be participants in the major study. They filled out the NSC in the Chinese version, and a factor analysis was used to build up construct validity. Four factors were extracted: nonproductive reactions, satisfactory responses, professional concerns, and falling behind. A comparison was made of these four factors with the five factors of the NSC in the English version. PMID- 9362717 TI - Psychiatric nursing with Australia's multicultural patients. AB - Despite Australia's officially acknowledged multicultural society, its health care system is monocultural; Anglo-Celtic and non-English-speaking background (NESB) clients are disadvantaged in terms of access and quality of service. To address this problem, current services need to be developed in a way that enables the system to be accessible and sensitive to the needs of NESB clients. One of the factors essential to the achievement of this goal is the education of psychiatric nurses. This article looks at the multicultural society, government policy and initiatives, and the education of psychiatric nurses to provide care to NESB clients in Australia. PMID- 9362718 TI - The cultural context of mental health nursing. AB - Culture includes the values, norms, and behaviors of a group. This article broadens the view of culture from that of a group of persons with common race or ethnicity and a shared belief system to include the clinical specialty of psychiatric-mental health nursing. Through a review of the American Nurses Association's (ANA, 1994), document A Statement on Psychiatric-Mental Health Clinical Nursing Practice and Standards of Psychiatric-Mental Health Clinical Practice, the values espoused by the leaders in the field are illuminated and compared with societal values reported in the literature. The implications of these values for nursing practice, education, and research are discussed. PMID- 9362719 TI - Intersecting race and gender in feminist theories of women's psychological development. AB - Although self-in-relation theory is the predominant feminist position on women's psychological development in the nursing literature, other voices and views, particularly from feminists of color, have challenged the thinking about the psychology of women. This article explores the intersectionality of race and gender in feminist theories of women's psychological development and mental health. It begins with a brief review of psychoanalytic feminism, focusing primarily on the work of Chodorow and what is labeled "self-in-relation" theory as it has been applied in (primarily mental health) nursing. This is followed by a discussion of the perspectives of several feminists of color concerning women's psychological development, perspectives that both challenge and concur with the views of psychoanalytic feminists. The final section presents the implications of these various feminist perspectives (and their challenges to each other) for feminist work in mental health nursing. PMID- 9362720 TI - Women's experiences of victimizing sexualization, Part I: Responses related to abuse and home and family environment. AB - Qualitative, interpretive research was conducted with ten adult women who felt that their experiences of learning about themselves as female and sexual had been harmful. The term "victimizing sexualization" was developed to identify this experience, and a thematic description of these women's experiences was derived. Components of their experiences were described within four major categories, including perceptions and descriptions directly related to abuse experiences, home and family environments, community and cultural characteristics, and longer term personal impacts. This article reports on two of the major thematic categories: perceptions and descriptions related to abuse experiences and home and family environment. Findings of this study establish "victimizing sexualization" as a meaningful women's health construct with important connections to feminist perspectives on women's lives. PMID- 9362721 TI - Women's experiences of victimizing sexualization, Part II: Community and longer term personal impacts. AB - This is the second of a two-part article describing the results of a qualitative study on women's experiences of victimizing sexualization. Ten adult women described their experiences of harmful learning about themselves as female and sexual. A four-part thematic description of women's experiences of victimizing sexualization was derived. This article reports on two of the major categories: community and cultural characteristics and longer term personal impacts. Findings of the study support the feminist position that the enactment of gender itself at social and cultural levels sometimes places women at risk for victimization. PMID- 9362722 TI - The experience of terminating an abusive relationship from an Anglo and African American perspective: a qualitative descriptive study. AB - A common question asked about abused women is, "Why don't they leave?" This qualitative study explored the experiences of 15 African American and 15 Anglo American women who had terminated abusive relationships. The constant comparative method of analysis of audiotaped interviews revealed a 3-phase process of leaving: being in, getting out, and going on. Participants endured abuse until they could relinquish the fantasy of a happy relationship. Differences in relationship power and public response to abuse distinguished the experiences of Anglo and African American participants. Findings support the notion of leaving as a social process with similarities across both groups. However, critical differences in responses suggest that leaving is a culture-bound experience. PMID- 9362723 TI - Providing sanctuary for battered women: Nicaragua's casas de la mujer. AB - A combination of participant observation and in-depth interviews (10 with key informants; 21 with battered women) was used to investigate wife battering in Nicaragua and the casas de la mujer, or women's centers, that have been established to help abused women. The results are presented within the context of the historical and structural realities of women's lives in Nicaragua and the sanctions and sanctuary framework of cultural analysis of wife battering. Nicaraguan wife battering is exacerbated in the context of cultural traditions of acceptance of wife beating, machismo, and the recent history of warfare. Findings about the relationship context and intervention outcomes were similar to those found in studies of battered women and shelters in the United States. The results were generally supportive of the framework, demonstrating the importance of women's solidarity groups, community sanctions against domestic violence, and sanctuary for battered women. PMID- 9362724 TI - Narrative interaction: creating a space for therapeutic communication. AB - This theoretical article explores the impact of ethnic appearance on the nurse client encounter from the perspective of Chicanas, women of Mexican descent. The issues raised for Chicanas, however, are applicable for members of many other ethnic groups, individuals whose identity is often constructed from the stereotypes and myths their appearance evokes. Ethnic minority women often experience a feeling of double jeopardy, enduring the consequences of living in a society that devalues both women and members of specific racial or ethnic groups. Research from nursing, counseling psychology, and sociology provide the bases for an examination of the mental health consequences of this double jeopardy. Narrative interaction, the sharing of personal stories, is offered as a therapeutic form of communication. Through narrative interactions, nurses may begin to understand the context of women's lives and learn what is meaningful for them, from their perspective. It is from the women themselves that nurses will begin to learn new meanings for their appearance and gain some understanding of their world. PMID- 9362725 TI - Nursing practice with incarcerated women: caring within mandated (sic) alienation. AB - The number of incarcerated women in the United States is increasing at an alarming rate. Incarcerated women often come from environments that are significant for violence, drug abuse, and a kind of chronic chaos. Many enter the penal system with acute and chronic physical problems along with mental health issues that have long gone unaddressed. From a critical hermeneutical perspective, professional and personal experience and dialogical engagement with other prison nurses are combined to examine the structure and development of caring practices behind prison walls. Analysis to date reveals the distorting and perverting effect prison systems have on the practice of nursing, a situation in which personal relationships are forbidden. In substantive ways, nurses are ordered not to care. PMID- 9362726 TI - A feminist analysis of women's depression during the childbearing year. AB - This article proposes a set of questions about difference, location, power, and representation that nurses can use to critique qualitative and quantitative studies for the utility of their findings in specific practice settings. It then uses these questions to conduct a feminist postmodern critique of a brief report of a longitudinal study about women's depression patterns throughout the childbearing year. PMID- 9362727 TI - Applying a feminist analysis model to selected nursing studies of women with HIV. AB - Women's mental health has been linked to oppression and to oppressive practices in health care. Feminist approaches to health care delivery and research have been suggested as a remedy for the subtle and overt oppression faced by women, and many nurses have used feminist principles to conduct and report their research and to critique existing studies. Though nursing authors have identified useful feminist guides for conducting and reporting research, few examples of the practice of feminist critiques of research are available in the nursing literature. This analysis synthesizes and adapts feminist principles from nursing literature and presents a feminist model to review selected nursing research reports of women with human immunodeficiency virus (HIV). A convenience sample of eight articles from nursing journals was examined for statements or implications that the author(s) (a) perceived the purposes of the study as benefiting women, (b) demonstrated an awareness of the structures and policies that oppress women, (c) were sensitive to issues of diversity, (d) were committed to social change, and (e) recognized the female participants' strengths. The selected articles were found to meet many of the feminist criteria, although these principles were not always explicitly addressed in the articles. PMID- 9362728 TI - Patient-driven interdisciplinary care planning (one year after implementation). PMID- 9362729 TI - Peer review unmasked. PMID- 9362730 TI - The science and technology of dialysis: new post-graduate program at Georgian College, Barrie, Ontario. PMID- 9362731 TI - Case study: a special need. PMID- 9362733 TI - Robin's place. PMID- 9362732 TI - When the system gets sick. Personality disorders in the church. PMID- 9362734 TI - AIDS overseas. Personal glimpses of a worldwide epidemic. PMID- 9362735 TI - Beyond broken dreams. A mother's journey through AIDS. PMID- 9362736 TI - AIDS other victims: a story of courage and faith. PMID- 9362737 TI - Christie Hinds's personal crusade fighting AIDS with faith, facts & friendship. Interview by Karen Schmidt. PMID- 9362738 TI - An unlikely lesson. PMID- 9362739 TI - When things go bump in the night. A story of forgiveness. PMID- 9362741 TI - Jim & Cindy Cooke-Dew from affluence to influence. PMID- 9362740 TI - Baby LUV. Resource moms mentor pregnant teens. PMID- 9362742 TI - Respite care lightening the caregiver's load. PMID- 9362743 TI - A lily for a nurse. PMID- 9362744 TI - Heavenly sunlight. PMID- 9362745 TI - Do I belong in women's health? PMID- 9362746 TI - Can a Christian thrive in women's health? PMID- 9362747 TI - Sexual assault: caring for survivors. PMID- 9362748 TI - Spousal abuse. Does anyone care? PMID- 9362749 TI - Violence on the job. Deescalating tensions before they explode. PMID- 9362750 TI - Handling harassment. PMID- 9362752 TI - When the Gypsies come. An insider's view into a mysterious culture. Interview by Jeanne M. Burger. PMID- 9362751 TI - Confessions of a night nurse. PMID- 9362753 TI - Stretched to my limits. PMID- 9362754 TI - Lessons from Garizim. PMID- 9362755 TI - Mourning for Mohousy. PMID- 9362756 TI - A nurse's spin on the potter's wheel. PMID- 9362757 TI - Forging ahead. Interview by Karen Schmidt. PMID- 9362758 TI - A missionary's prayer: the worth of a woman. PMID- 9362759 TI - Northern exposure. Interview by Sylvia Bjorkman. PMID- 9362760 TI - A family for Josue: pediatric practitioner Maureen Horsley faces a transcultural ethical dilemma. PMID- 9362761 TI - The flying hospital. Interview by Adriana Clare. PMID- 9362762 TI - Nursing in Zimbabwe. Walking a tightrope without a net. PMID- 9362764 TI - Chicken bones & beef hearts: creative teaching at Tenwek. Interview by Betty M. Hockett. PMID- 9362763 TI - Soybeans & the kingdom of God. PMID- 9362765 TI - A day in the life of Genese Kudiangela. Interview by Glen E. Miller. PMID- 9362766 TI - Working toward shalom. PMID- 9362767 TI - The caring congregation. A healing place. PMID- 9362768 TI - An unexpected healing. PMID- 9362769 TI - Answering God's call. Interview by Karen Schmidt. PMID- 9362770 TI - A long-term relationship with NCF. PMID- 9362772 TI - Loving hands. PMID- 9362771 TI - What does a parish nurse do? PMID- 9362773 TI - Nursing through the lens of faith. A conceptual model. PMID- 9362774 TI - Getting started. Parish nursing in a rural community. PMID- 9362775 TI - Pastor at risk. PMID- 9362776 TI - A profile of parish nurses. PMID- 9362777 TI - What should the church do about health? PMID- 9362778 TI - Congregational nurse practitioner: an idea whose time has come. PMID- 9362779 TI - Out of the earthquake. Coping with cataclysmic change. PMID- 9362780 TI - Nursing's walking wounded. PMID- 9362781 TI - Finding Hope. When everything's up for grabs. PMID- 9362782 TI - Suddenly single. When you lose a mate. PMID- 9362783 TI - Walking through the five. Fostering faith in times of loss. PMID- 9362784 TI - Surprised by tears. PMID- 9362785 TI - American milk mama. PMID- 9362787 TI - Where was God? PMID- 9362786 TI - A cure for wringing hands. PMID- 9362788 TI - Aaron Golding's gift of grace. PMID- 9362789 TI - Nursing from the heart. PMID- 9362790 TI - Claiming our heritage. Bridge to a lasting future. PMID- 9362791 TI - Fabiola. From arrogance to charity. PMID- 9362793 TI - Hildegard of Bingen. A woman of vision. PMID- 9362794 TI - Kaiserswerth revisited. Putting the care back into health care. PMID- 9362792 TI - Charlotte Aikens. An altered call. PMID- 9362795 TI - A heart of compassion. How nursing started in Norway. PMID- 9362797 TI - A light in the darkness. NCF in Estonia. PMID- 9362796 TI - The NCF story. Making Christ known in nursing. PMID- 9362799 TI - Remembering nursing in the '20s. PMID- 9362798 TI - Nursing ethics. Growing beyond rules of conduct. PMID- 9362800 TI - The capping ceremony that refused to die. PMID- 9362801 TI - The nursing pin. PMID- 9362802 TI - Hospital train number 58: nursing at the front. Interview by Barbara Craig. PMID- 9362803 TI - Spiritual care documentation: where is it? PMID- 9362804 TI - Documenting congregational nursing care: a model. PMID- 9362805 TI - "Why I love nursing?". PMID- 9362806 TI - Therapeutic touch: healing science or metaphysical fraud? PMID- 9362807 TI - A new age for nursing. PMID- 9362808 TI - A brief history of theosophy. PMID- 9362809 TI - Reconciling with a new age colleague. PMID- 9362810 TI - Reconciling with God in a new age unit. PMID- 9362811 TI - 5 ways to build lasting interracial friendships. PMID- 9362812 TI - Moving beyond burnout. PMID- 9362813 TI - Healing. Ted's break with God. PMID- 9362814 TI - I believe in miracles! PMID- 9362815 TI - To live until I die. PMID- 9362816 TI - Opportunity lost. PMID- 9362817 TI - Dad's link to survival. PMID- 9362818 TI - Living with a secret disease: OCD. PMID- 9362819 TI - Keeping body & soul together. PMID- 9362820 TI - The integration of unlicensed assistive personnel using an "Expanding Our Skills" workshop. AB - Emphasis on cost containment in health care is forcing healthcare institutions to implement skill-mix changes in patient care staffing. Research has shown that education for the nursing staff is imperative for successful implementation of such changes. In this article, the author describes the education program used to successfully facilitate the use of obstetric technicians in a large labor and delivery unit. Role clarification and education regarding delegation skills are key factors discussed. PMID- 9362821 TI - Teaching strategies and knowledge retention. AB - This project compared nurses' knowledge retention after completion of either a competency-based, written self-learning module or a competency-based, didactic lecture module. Using a pretest/posttest quasiexperimental design, a convenient sample was selected from a group of registered nurses who attended a mandatory yearly review of standards from the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) and the Occupational Safety and Health Association (OSHA). The 67 subjects were given pretests, the same content material using the two types of presentations, and posttests. An analysis of covariance was used to determine posttest differences between the groups, controlling for pretest scores. Results indicated no significant differences among posttest scores of the treatment group and the control group; alpha level was 0.05. Knowledge retention essentially was the same, regardless of the antecedent teaching methodology. The advantages of one teaching method versus another may be in the flexibility afforded the staff educator. After desired outcomes are identified, a teaching method can be determined based on the staff educators' requirements, the resources available, and the learners' needs. PMID- 9362822 TI - Educating the ethics committee. AB - Ethics committees are being formed in all types of institutions. Education is the foundation of a functioning committee. The purpose of the education is to prepare the multidisciplinary committee members to deal with difficult ethical issues in a changing healthcare environment. In this article, the authors address different methodologies that can be used for educating ethics committees. PMID- 9362823 TI - The effects of an aggressive behavior management program on nurses' levels of knowledge, confidence, and safety. AB - Violence in the workplace is increasing, and unfortunately, hospitals are not exempt from the problem. Nurses are the primary caregivers in hospitals and are more likely to encounter violence because of the amount of time spent in direct patient care. Many nurses have not been trained to manage explosive situations. This project was developed to provide a program titled, "Managing Aggressive Behavior," to nurses and to measure and compare the differences in levels of knowledge and feelings of safety and confidence among nurses who attended the workshop versus a group who did not. The data revealed a significant difference in knowledge in the program group (P < 0.001) but no significant changes in safety (P = 0.367) or confidence (P = 0.440). No significant changes were found among the variables in the treatment group. Suggestions for further research and teaching are given. PMID- 9362824 TI - The development of an acute care case manager orientation. AB - The authors describe the development of an inpatient acute care case manager orientation in a community hospital. Benner's application of the Dreyfus model of skill acquisition provides the basis for the orientation program. The candidates for the case manager position were expert clinicians. Because of the role change it was projected that they would function as advanced beginners. It was also predicted that, as the case managers progressed within the role, the educational process would need to be adapted to facilitate progression of skills to the proficient level. Feedback from participants reinforced that the model supported the case manager in the role transition. In addition, the model provided a predictive framework for ongoing educational activities. PMID- 9362825 TI - The relationship between critical thinking and self-concept in staff nurses and the influence of these characteristics on nursing practice. AB - Thirty-five nurse managers were interviewed, and 100 staff nurses were tested using the California Critical Thinking Skills Test (CCTST) and the Tennessee Self Concept Scale (TSCS) to determine if a relationship existed between critical thinking and self-concept. Correlations (Pearson r) showed no statistically significant relationship (r = 0.1097, P > 0.05). Comparison of the results of the California Critical Thinking Skills Test between groups with differing levels of nursing education indicated that scores for nurses with a baccalaureate were statistically and significantly higher than the scores of nurses with an associate/diploma degree (ANOVA F = 3.03, P = 0.03). Implications for nursing education and practice are discussed. PMID- 9362826 TI - Redesigning the role of the centralized educator. PMID- 9362828 TI - Where are we now? Evaluating two decades of group interventions with adult cancer patients. AB - Substantial evidence suggests that psychosocial interventions are effective in reducing the psychological distress associated with cancer. As the requirement for more cost-effective health care becomes a global concern, considerable focus has been directed towards group interventions with cancer patients. This review examines the literature of intervention groups provided across a wide range of approaches used and illustrates the mental health benefits seen from these studies. Methodological limitations in previous work are examined and ways towards improving research using cancer intervention groups are suggested. PMID- 9362827 TI - Mental illness and criminal behaviour: a literature review. AB - The purpose of this paper is to review the current literature in relation to mental illness and criminal behaviour. The material presented for discussion was selected from forensic and general psychiatric literature. However, a number of important publications, policy documents and independent reports were used to explore the debate surrounding this subject. Contemporary studies of prison populations in the UK and abroad illustrated the difficulty in relating mental illness to crime. Papers presenting research in the UK revealed important implications for mental health policy and the way in which the penal system deals with mentally disordered offenders. The literature reviewed provided arguments for and against an association between mental illness and criminal behaviour. Methodological problems associated with criminological and psychiatric research were addressed in relation to the exploration of whether people suffering from a mental illness are more dangerous or violent than other people. Research papers focusing on public reaction to mentally ill people living in the community provided important considerations when addressing mental illness and criminal behaviour in the context of care in the community policy. This paper will be of interest to a broad range of mental health professionals, particularly those working with individuals who have a history of mental illness and violent behaviour, or mental health professionals working with mentally disordered offenders. PMID- 9362829 TI - Understanding the psychological impact of rape and serious sexual assault of men: a literature review. AB - Until recently, very little attention has been paid to male victims of sexual abuse in childhood and male victims of rape and sexual assault in adulthood. Increasingly, researchers and clinicians are turning their attention to the particular problems encountered by male victims of abuse and sexual assault. Recent changes in British Law have acknowledged the existence of rape of male victims and have highlighted the need to identify the number of male victims of sexual assault and plan appropriate clinical services. A review of the literature reveals very little British empirical research on the psychological impact of rape upon male victims, although the studies that have been carried out provide clear evidence of a wide range of psychological consequences, both in the immediate period following the assault and in the long-term. Differences and similarities with female victims of rape are discussed. The particular problems encountered by male victims mean that they are even less likely than female victims to report an assault; when they do seek help the most pervasive themes that emerge from the literature concern their problems in reconciling their masculine identity with their experience of being a sexual victim. Issues concerning treatment of male victims are also discussed. PMID- 9362830 TI - Schizophrenia: revisited. AB - Schizophrenia is a devastating illness for the affected individuals and their families. Health care providers and researchers are also challenged by the clinical heterogeneity of this disorder. The goal of the present paper is to offer an updated overview of the aetiology, definition, clinical manifestations and pharmacological and psychosocial treatments of schizophrenia. Finally, some future directions for psychiatric nursing will be suggested in light of the existing knowledge of schizophrenia. PMID- 9362831 TI - Case management: a week in the life of a clinical case management team. AB - This paper describes the work of a clinical case management core team (four nurses and an occupational therapist) during the course of a week. Information was gathered through non-participant observation of the team by two independent researchers. Transcripts produced from the data recorded were examined. From this, seven categories of activity were identified: planned client contact; unplanned client contact; family/carer contact; liaison; administration; team information sharing and supervision, training and personal development. These categories were felt to encompass the range of activities practised by the team. The amount of time that case managers spent engaged in these core functions was calculated. Detailed examples are presented. Results are discussed with reference to Kanter's components and principles of clinical case management. PMID- 9362832 TI - The nursing process in crisis-oriented psychiatric home care. AB - Crisis-oriented psychiatric home care is a recent development in the Dutch mental health care system. Because of the difference between psychiatric care in the home and in the hospital, an action research project was initiated. This project was directed at the nursing process and the nurses' role and skills in psychiatric home care. The main goal of the project was to describe and to standardize nursing diagnoses and interventions used in crisis-oriented and long term psychiatric home care. The development of supporting methods of assessment and intervention were also important aspects of this project. In this article a crisis-oriented psychiatric home care programme and the first developmental research activities within this programme are described. To support the nursing process, the development of a nursing record and an assessment-format, based on Gordon's Functional Health Patterns (FHP), took place. By means of content analysis of 61 nursing records, the most frequently stated nursing diagnoses, based upon the North American Nursing Diagnosis Association (NANDA) taxonomy, were identified. The psychiatric diagnostic categories of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) were also collected. The most common categories found were those of mood disorders and schizophrenia or psychotic disorders. Seventy-five per cent of the nursing diagnoses showed up within four FHP: role-relationship, coping-stress tolerance, self-perception/self concept and activity-exercise. The nursing diagnosis of 'ineffective individual coping' was stated most frequently. This is not surprising because of the similarities in the definitions of this nursing diagnosis and the concept of 'crisis' to which the psychiatric home care programme is oriented. Further research activities will be focused on standardization of nursing diagnosis and the interventions that nurses undertake in this type of care. PMID- 9362833 TI - A model for analysis of the nurse-patient interactive process (MAIP). AB - A model for analysis of the nurse-patient interactive process (MAIP), based on the analysis of the content of that interaction, is proposed as a method for determining appropriate psychosocial nursing diagnoses for the patient. The model focuses on the qualitative aspects of the phenomenon of interaction. The MAIP permits a systematic analysis of the nurse-patient interaction, and in turn will provide guidance for the professional in their actions in the interactive process. PMID- 9362834 TI - Madness in her method: creating a 'survivor frame' for mental health research. PMID- 9362835 TI - Postmodernity and psychiatric nursing: a commentary. PMID- 9362836 TI - Postmodernity and psychiatric nursing--take two. PMID- 9362837 TI - Endovascular grafting of abdominal aortic aneurysms. AB - Abdominal aortic aneurysm (AAA) is a common condition that vascular nurses see daily in their practice. Ruptured AAA is the thirteenth leading cause of death in the United States. Increasingly, vascular surgeons are facing older patients with severe comorbid conditions and an AAA. These factors have led to the development of less invasive techniques for repairing AAAs. Endovascular grafting is a technique currently being performed on selected patients. Benefits of this procedure include a small femoral incision, fewer cardiopulmonary risks than the traditional surgery, rapid recovery, short hospital stay, and a decrease in overall cost. Nurses are responsible for patient education, assessment, and evaluation of patients undergoing this procedure. PMID- 9362838 TI - Dissection of the aorta: a clinical update. AB - Aortic dissection is a catastrophic condition that occurs precipitously and is most commonly associated with a history of hypertension or cystic medial necrosis. Although the clinical presentation is quite variable, the heralding symptom is almost always severe chest or back pain. Aortic dissection is categorized as Type A if it involves the ascending thoracic aorta and Type B if it involves only the aorta distal to the left subclavian artery. During the first 48 hours, acute Type A dissection has a mortality of greater than 1% per hour; it is treated as a surgical emergency. Surgical repair for Type B dissection is generally reserved for patients who have persistent pain, intractable hypertension, or evidence of dissection progression. In all patients with aortic dissection, pharmacologic antihypertensive and negative inotropic therapy is essential to control extension of the dissection process. Vigilant monitoring of blood pressure and serial assessment to detect dissection progression are the key components of nursing management. PMID- 9362839 TI - Low-molecular-weight heparin. AB - Traditionally unfractionated heparin is given in the hospital and then followed with 3 to 6 months of oral anticoagulant therapy. Hospitalization is expensive, intravenous administration of heparin limits mobility, and the patient is exposed to iatrogenic infections. Depolymerization of heparin results in low-molecular weight heparin (LMWH), which has advantages over unfractionated heparin. The advantages are better bioavailability, a longer half life, and more predictable anticoagulant activity. Because of these characteristics it can be given subcutaneously, without laboratory monitoring, in a dose that is calculated by the patient's body weight alone. Studies have shown that LMWH is as effective as unfractionated heparin at preventing clot extension and pulmonary emboli. and is possibly safer. There are a number of LMWH preparations available worldwide, and clinical trials have been conducted in a number of countries. This article will review the clinical properties, uses, complications, and nursing implications associated with LMWH. PMID- 9362840 TI - Treatment and prevention of varicose veins. AB - Many factors predispose human beings to venous disease of the lower extremities, and this condition affects approximately eighty million Americans. Its manifestations may appear to be little more than a cosmetic nuisance, yet may be an indication of a more serious underlying problem undetected by visual inspection. Venous disease is also capable of producing a plethora of uncomfortable symptoms, and left untreated, may progress to cutaneous pigmentation, dermatitis, ulceration, hemorrhage, or superficial thrombophlebitis. Although uncomplicated cases of the disease are more common, venous disease should not be taken lightly. Steps to retard disease expression and progression should be implemented whenever possible. The purpose of this article is to aid the nurse in providing accurate information to patients about the disease process, treatment options, and interventions for its prevention. PMID- 9362841 TI - Embolization of a lacerated artery after percutaneous drainage of a pelvic abscess. PMID- 9362842 TI - [Understanding of environmental impact with inpatients based on structural modeling]. AB - This study examined how inpatients perceive environmental impacts using the ISM(Interpretive Structural Modeling)method. 18 new items among inpatients perceiving the environmental impacts were selected through a discussion with three researchers, two nurses, and six patients. This was applied to two inpatients who were not in the same ambulatory state in order to establish the validity of the structural models. As a result, the structuring models showed the difference depending on each patient. Therefore the structuring model is effective to assess the environmental impacts on individuals. PMID- 9362843 TI - [Quality of life for patients with intractable diseases. Subjective satisfaction of patients with Parkinson's disease]. AB - More than 20 years have passed since policies for dealing with intractable diseases have been instituted in Japan. This study was carried out to clarify which factors tend to promote a patient's subjective satisfaction with his or her quality of life. The subjects were 62 male and 51 female patients with Parkinson's disease. Their average age was 68.8 years. The results were as follows: 1. Patients placed more importance on trying to understand the pathophysiology of the disease than trying to improve their better-life with the disease. 2. Most male patients received care from a family member, whereas most female patients received care from a non-family member. 3. Multiple logistic regression analysis indicated that a) patients who understand how to improve their better-life with Parkinson's Disease are four times more satisfied(on-a subjective basis)than patients who do not understand how to improve their better life, and b) patients who have a supportive caregiver are twice as satisfied as those who do not. These findings suggest that, in order to increase the subjective satisfaction of Parkinson's disease patients, it is important for them to have a supportive caregiver and to help them understand how to improve their better-life. PMID- 9362844 TI - [The relationship between professional autonomy and demographic and psychological variables in nursing]. AB - The purpose of this study is to investigate the relationships of professional autonomy in nursing with demographic and psychological variables. The measure of professional autonomy in nursing is constructed by five factors, "Cognition", "Performance", "Concrete judgement", "Abstract judgment" and "Independent judgment", respectively and interpreted to represent the professional work abilities of nursing. Age, years of experience of nursing, arrangement of work place in the hospital, position level and educational background of nursing are selected as demographic variables. Psychological variables used in this study were intention to continue at work as a nurse, work satisfaction and motivation, self confidence and self evaluated aptitude toward nursing. Three-hundred and seventy professional nurses in the public hospital were administered a questionnaire including the five-point scale for professional autonomy in nursing and several demographic and psychological variables. The main results were as follows: (1) Each of the sub-scale scores of professional autonomy in nursing had significant and positive correlations with age, years of experience, work satisfaction and motivation, self confidence and aptitude toward nursing. (2) Nurses worked at the intensive care unit and operation room were significantly higher scores of professional autonomy in nursing than the nurses at the ward and the outpatient clinic. (3) Professional autonomy in nursing was totally increasing with the increase of nurse's position and years of experience. (4) Self confidence, position level and the kind of nursing license were the most explicable variables of professional autonomy in nursing. PMID- 9362845 TI - [Transmission of methicillin-resistant Staphylococcus aureus in a hospital for aged and chronically ill inpatients]. AB - When we tested bacterial contamination in the linens of aged or chronically ill inpatients in a general hospital (114 beds), 11 out of 60 patients were found to have methicillin-resistant Staphylococcus aureus (MRSA). Two of these were MRSA infections. Furthermore, 6 patients mostly elderly and with chronic diseases, were newly infected with MRSA after this surveillance period. So as to clarify the transmission route of MRSA in the hospital, we classified 12 MRSA strains into 4 types by several criteria such as types of coagulase, enterotoxin, toxic shock syndrome toxin, sensitivity to antibiotics, plasmid contents, and restriction endonuclease digestion patterns of chromosomal DNAs. At the same time, we followed up the movement of patients in wards and conditions of patient contact with medical staff in the hospital. The data obtained revealed a specific correlation between one of the MRSA strains and a doctor, suggesting a contribution from medical staff to the transmission of MRSA in the hospital. It is necessary, therefore, to practice more careful protection procedures against bacterial infection especially in hospitals for aged and chronically ill patients who are vulnerable to various infectious agents. PMID- 9362846 TI - [Effects of cancer in children on siblings and their siblingship]. AB - The purpose of this study was to describe the relationships between children with cancer and their siblings. Eighteen children with cancer and twenty-two of their siblings completed the questionnaire which included the 22 items related to the siblingship. Eighteen mothers answered the semi-structure interview, which asked the mother's recognitions of their family life during staying in hospital, the siblingships between patients and siblings, and the effects of childhood cancer on siblings. To determine their siblingship, responses of patients and siblings were compared with the criterion data using means and standard deviations of each item. In addition each item of mothers' data was calculated percentages to determine the effects on siblingships. It was suggested that the siblingships between patients and their siblings were similar to siblingship between healthy children. However, both children with cancer and their siblings had more positive feelings and less negative feelings each other. On the other hand, it was suggested that the effects of changes of their family life due to staying in hospital on siblings were severe. PMID- 9362847 TI - [Family assessment: anxieties experienced by mothers staying with their hospitalized sick children]. PMID- 9362849 TI - [Survey and research (10). Steps in the survey research process for nursing practice: statistics (4)]. PMID- 9362848 TI - [Basic study on blood pressure measurements with a digital sphygmomanometers]. AB - In the present study, digital sphygmomanometer (SMmeter)(Omuron Digital 709 Fuzzy and Digital 806F)for family use and 24 hour ambulatory SMmeter were checked in terms of reproducibility (CV%) of blood pressure(BP) measured and comparison of measured BP with Digital SMmeter with those measured with mercury SMmeter, the golden standard. Reproducibility of BP measured with Hg-SMmeter was less than 4%, with each Digital SMmeter less than 9%. Inter-unit reproducibility was less than 5% in each SMmeter. Systolic BP measured with 24 hour ambulatory SMmeter were higher by 2-4% than BP measured with Hg-SMmeter, diastolic BP higher by 4-9%. Systolic BP measured with Digital 709 Fuzzy were higher by 5-10% than Hg-SMmeter in lower range of systolic BP to be actually measured, in 130-170 mmHg both values almost coincident, in more than 170 mmHg Digital 709 Fuzzy lower by 2-7%. Diastolic BP measured with Digital 709 Fuzzy were higher by 10-15% than Hg SMmeter in lower range of diastolic BP to be actually measured. In more than 80 mmHg both values were almost coincident. Systolic BP with Digital 806F were higher by 1.5-7%, diastolic BP higher by about 10% than the value with Hg SMmeter. In conclusion, by taking account of different reproducibilities and characteristics of SMmeter, home BP monitoring can be performed by patient or/and his family. PMID- 9362850 TI - Midwifery in Australia and surrounding regions. PMID- 9362851 TI - Midwifery education for safe motherhood. AB - OBJECTIVE: To determine the useability (relevance, clarity and quality of content), applicability (ease of use) and accessibility (structure and form) of a series of new safe motherhood midwifery education modules. DESIGN: Questionnaire survey and focus group discussions, preceded by a two week clinical skills course and an eight day orientation to using the modules. SETTING: Nursing and midwifery education institutions, regional training centres, acute-care hospital facilities and community settings in Ethiopia, Fiji, Lesotho, Mozambique and Nepal. PARTICIPANTS: Thirty-six teachers, 82 midwives, nurse-midwives and auxiliary nurse-midwives from practice settings, and 60 post basic midwifery students. KEY FINDINGS: Overall it was found that the introductory information and the technical content of the modules were easy to understand and use as were the instructions for both teachers and students. The presentation of the material was orderly and easy to follow; the language was comprehensible; and the illustrations were appropriate, clear and facilitated teaching. The teachers found that they were able to use most of the teaching/learning methods, teach most of the skills in the modules, and use the guidelines for assessing competence. The main difficulties encountered included adherence to the recommended time frame for some of the classroom sessions; the limited availability of clinical cases for teaching the specific skills in the modules and time limitations in the clinical area for practising the skills; and the provision of transport for community visits, data to complete community profiles, and time to complete other planned community activities. The students identified the need for a set of learning materials which they could take with them for future reference, and both teachers and students expressed concern about resources to support, and legislation to cover, the application of the skills taught/learned. KEY CONCLUSIONS: The modules have the potential to strengthen and support the education of midwives in developing countries, enabling them to make motherhood safer and contribute to a reduction in maternal mortality by providing better midwifery care. PMID- 9362852 TI - Routine care of women experiencing normal deliveries in Zambian maternity wards: a pilot study. AB - OBJECTIVE: To describe the routine care of women during normal labour and delivery, and the immediate care of newborn babies in Zambia at different levels of health care. DESIGN: A descriptive survey carried out between July 1994 and January 1995. SETTING: Eleven maternity facilities, one University teaching hospital, two urban health centres and eight rural hospitals in one province in Zambia. PARTICIPANTS: Eighty-four women in normal childbirth and their babies studied from admission to the labour ward until time of discharge from the labour ward. MEASUREMENTS AND FINDINGS: Observations related to the care of the women during normal labour and delivery, and the immediate care of the baby. The findings show that women were confined to bed during the whole labour and delivery period, food and drinks were withheld, and no gowns were provided. None of the women were allowed to have a companion present during labour. Fetal monitoring was inconsistent and the partograph was either not used or partly lacking. All women were delivered in a lithotomy position and primiparae were fixed in stirrups during the second and third stages of labour. There was general lack of support for early mother/baby contact, prevention of hypothermia in the babies and early initiation of breast feeding. IMPLICATIONS FOR PRACTICE: Based on our findings we suggest that many present maternity ward routines, both physiological and psychological, should be carefully studied. It is also suggested that the midwives reorient their caring practices to more culturally and evidenced-based maternity care. Refresher courses for midwives who have been working for many years are recommended. PMID- 9362853 TI - Whose welfare in the labour room? A discussion of the increasing trend of fathers' birth attendance. AB - OBJECTIVE: To review the key literature on fathers' birth attendance, discussing: factors contributing to the increasing trend in men's birth attendance; the different roles and responsibilities men may adopt in the labour room and the implications; and, particularly, the education needs of both the expectant fathers and the professionals. LITERATURE SEARCH: The literature reported here is part of a larger longitudinal ethnographic study of men's experiences of pregnancy and birth, which to date has generated 190 relevant articles. The literature was identified using: the Midwifery Information Resource Service (MIDIRS), PsychLit, Cinahl, Medline, and the Cochrane Pregnancy and Childbirth Database. Keywords were: men, fathers, pregnancy, birth, and birth supporters. Literature was also identified using references quoted in papers and hand searching of journals. KEY CONCLUSIONS: Changing cultural and professional attitudes have encouraged fathers' birth attendance, reflected in an increasing volume of research. This research concentrates almost exclusively on labour coaching roles, neglecting exploration of any independent needs men may have. IMPLICATIONS FOR PRACTICE: A greater awareness of men's experiences will inform midwives and childbirth educators to effectively provide for men's needs during pregnancy and birth. PMID- 9362854 TI - Too much like school: social class, age, marital status and attendance/non attendance at antenatal classes. AB - OBJECTIVE: To investigate patterns of attendance and non-attendance at National Health Service antenatal classes of first-time mothers in the indigenous white population of a large northern city of the UK. DESIGN: Survey using questionnaires, and selected participants were then given an in-depth interview. SETTING: Five maternity wards in two large northern hospitals in the UK. In-depth interviews took place in the respondents' homes. PARTICIPANTS: Fifty newly delivered women were surveyed of whom 18 took part in the follow-up interviews. FINDINGS: There was a clear hierarchy in attendance and non-attendance based on social class, with middle class women being the most regular attenders, closely followed by older, married, working class women. However, overall social class differences were found to be accounted for by the overwhelming non attendance of young, unmarried, working class women. Older, married, working class women were found to have attendance patterns which were close to their middle class counterparts, and what differences there were seemed to be based on material factors. KEY CONCLUSIONS: The majority of women felt that antenatal classes were too technical and did not address emotional and psychological issues. However, young, single unmarried women perceived the classes most negatively. If midwives are to attract such young women, their fears and their need for peer support will have to be recognised. PMID- 9362855 TI - Early or late bath during the first stage of labour: a randomised study of 200 women. AB - OBJECTIVE: To compare obstetric outcome after a bath offered to women on two different occasions during the first stage of labour. The aim of the study was to determine whether an early bath affected the progress of labour and the use of analgesia when compared with a late bath during the first stage of labour. DESIGN: A randomised prospective pilot-study. SETTING: The delivery ward at Ostra Hospital in Goteborg. PARTICIPANTS: Two hundred women, at low obstetric risk. INTERVENTIONS: The women were randomised to either the 'early bath group' or the 'late bath group'. The women in the 'early bath group' had a bath before a cervical dilatation of 5 cm, while the women in the 'late bath group' had a bath after the cervix was 5 cm dilated. MEASUREMENTS AND FINDINGS: The women in the 'early bath group' had a longer time period from established labour to delivery (9.8 hours) compared to the 'late bath group' (8.5 hours) (p < 0.004). A higher proportion of women in the 'early bath group' needed oxytocin administration (57%) compared to the 'late bath group' (30%) (p < 0.01). Epidural analgesia was used by 27% of the women in the 'early bath group' and by 9% in the 'late bath group' (p < 0.001). One baby in the 'early bath group' had clinical signs of infection and required antibiotic treatment. No cases of amnionitis or endometritis were present in the women. KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: The findings suggest that a bath during the first stage of labour should preferably be used after a cervical dilatation of 5 cm to avoid prolonged labour, and an increased use of oxytocin and epidural analgesia. PMID- 9362856 TI - Knowledge of and preference for the DOMINO delivery option. AB - OBJECTIVE: To examine women's knowledge of and preference for the DOMINO (Domiciliary In and Out) delivery option in order to explain why uptake is lower than might be expected. DESIGN: Descriptive study using a self completion postal questionnaire. SETTING: Mid Staffordshire Health Authority (now part of South Staffordshire Health Authority). SUBJECTS: A systematic random sample of 1568 women aged 16-44 drawn from the Staffordshire Family Health Services Authority register of patients registered with a general practitioner. All women were included, regardless of childbirth experience. MAIN OUTCOME MEASURES: Preference and knowledge levels for this delivery option. MAIN FINDINGS: The response rate was 74%. Thirty-nine per cent had heard of the DOMINO option prior to receiving the questionnaire. Sixteen per cent expressed a preference for this option (95% CI 11.1-21.9). Some women who expressed a preference were excluded owing to high risk factors, giving an adjusted preference of 11% (95% CI 5.2-16.4). Preference was not related to either age, pregnancy experience or previous knowledge. CONCLUSIONS: More women expressed a preference for the option than would be expected from examination of national and local uptake figures. Lack of knowledge appears to be an important factor in explaining the low uptake. Purchasers, therefore, need to set contracts reflecting more realistic preferences and ensure that women have information on all options available to them, so that at the beginning of pregnancy women are enabled to make a shared decision on the choice of delivery. Both purchasers and providers need to monitor uptake and levels of knowledge. PMID- 9362857 TI - The Internet as a marketing tool for LNCs. PMID- 9362858 TI - Learn to play the court room game. PMID- 9362859 TI - A consulting lesson from the road. PMID- 9362860 TI - Competitive marketing strategies. PMID- 9362861 TI - Anesthesia standards. PMID- 9362862 TI - Spotting red flags in workers' compensation cases. PMID- 9362863 TI - Stress management takes work. PMID- 9362864 TI - Whose needs are being met? PMID- 9362865 TI - Impact of leadership development on competencies. AB - Managed care has changed role expectations for front-line nurses. Roles now include outcome management, team coordination, and guardianship of patient's continuity along the continuum. Organizations are investing in leadership development training for non-management nurses in hopes that such competencies will enhance their value-added competitive edge, but data are needed to validate the value of such training to the organization. Authors report the self-perceived competencies in leadership understanding and ability (in a study of 87 participants) before and after leadership development training that focused on: planned change, communication, conflict, group dynamics, systems theory, and oppressed group behavior. Significant increases were reported in both understanding and ability to perform stated competencies both immediately after and 3 months after 3 days of training. Self-perceptions of both leadership understanding and ability before leadership training were higher for those with advanced degrees and/or those in management positions. However, some of these differences became insignificant after training. PMID- 9362866 TI - Family caregiving: who provides the care, and at what cost? AB - Today, there are an estimated 1.6 million people over 65 years of age who require assistance with two or more daily activities. This number is projected to rise to 2.1 million by 2001, with fewer family caregivers expected to be available to provide this informal care. Seventy-two percent of unpaid family caregivers are women, the majority of whom are mid-life daughters or daughters in law. Uncompensated care to the frail elderly requires an average of 28 to 39.9 hours per week of custodial care. The financial impact on informal caregivers includes: 9% of family caregivers who leave the labor force to provide care, 29.4% who adjust their work schedules, and 18.1% who take time off without pay. The estimated annual value of uncompensated kin care in 1990 was $18 billion. Thirty two percent of all family caregivers are categorized as poor or near-poor at incomes that are less than 125% of the federal poverty level. PMID- 9362867 TI - An academic nursing clinic's financial survival. AB - The authors suggest that academic institutions build business-oriented policies and practices into the development of any nurse-run clinic to set the stage for financial independence when special or development funding ends. One university affiliated program that provides 4,000 to 5,000 annual visits drastically changed its strategies when threatened with closure after free rent and other subsidies were withdrawn. The growing emphasis on ambulatory care roles for nurses at all levels makes such clinics critical to the success of the broad-based curricula of nursing education programs, as well as the clinic's value to communities they serve. Funding difficulties frequently threaten the existence of such nurse-run clinics once the initial grant funding is no longer available. This has caused a new emphasis on running such clinics in a business-wise manner. Among the strategies initiated were: direct full-pay at the time of service; a realistic business management plan; aggressive planned marketing; contracts and agreements with other agencies; obtaining provider status with selected HMOs. PMID- 9362868 TI - Differentiated nursing practice: assessing the state-of-the-science. AB - The authors present their findings following an exhaustive literature review of research on differentiated nursing practice (DNP) that used a number of tools to measure various aspects of DNP that are applicable across the health care delivery continuum. Issues related to DNP include: optimal nursing care, matching patient needs with nurse competencies, effective use of nursing resources, equitable compensation, career satisfaction, loyalty to employers, and enhanced prestige of the nursing profession. One 1992 Massachusetts study of a three-role oncology unit project (including patient care manager, clinical nurse, and patient care technician), showed positive change in five criteria including: standards of nursing care, actual care hours, average labor costs, job satisfaction and patient satisfaction. A 1990 Arizona study that included unit assistants concluded that DNP supported a decline in the use of supplemental staff and staff overtime which led to cost savings, and increases in the actual hours of care and nurse satisfaction. PMID- 9362869 TI - Development of a nurse intrapreneurial role: patient care manager. PMID- 9362870 TI - Development of telephone nursing practice standards. PMID- 9362871 TI - Am I working too hard or too long? PMID- 9362872 TI - HCFA's challenge: quality programs, happy voters. PMID- 9362874 TI - Leadership: when success leads to failure. PMID- 9362873 TI - Balanced Budget Act of 1997 becomes a reality: brings major changes to health care. PMID- 9362875 TI - The extinction of the nursing species. PMID- 9362876 TI - Dehydration and hydration in the terminally ill: care considerations. AB - Debate continues about whether to withhold or withdraw intravenous, subcutaneous, or nasogastric hydration in the terminally ill. Nurses may be confronted with situations where the terminally ill patient or family must make a decision regarding hydration. Therefore, nurses must be knowledgeable about terminal dehydration literature and research. This article is a review of the literature on terminal dehydration. The focus is on the definition of terminal dehydration, physiological benefits and disadvantages of terminal dehydration, rationale for hydrating, review of research in terminal dehydration, physiological basis for comfort in the terminally dehydrated, and suggestions for research and practice. PMID- 9362877 TI - Academic dishonesty among nursing students. AB - Student cheating on college campuses is believed to be a common occurrence, but academic dishonesty among nursing students is a source of legitimate concern to nursing faculty members because of its potential effect on present and future professional practice. Strategies are outlined that can promote academic honesty in the nursing program through moral and character development of nursing students, teaching moral decision-making skills, role-modeling of honest academic behavior, and developing and enforcing an appropriate academic integrity policy. PMID- 9362878 TI - Stigma and ageism: compounding influences in making an accurate mental health assessment. AB - Stigma and ageism are two phenomena that greatly affect the accurate assessment of mentally ill elderly and, ultimately, their health care. Healthcare providers, doctors, nurses and others, including mental-healthcare providers, would benefit from awareness of stigma and ageism and their impact on psychiatric care for the elderly, many of whom also have physical problems. Understanding these influences may assist providers to make more accurate diagnoses and a more appropriate plan of care. This paper defines stigma and ageism and their potential and actual influences on assessment and interventions for the mentally ill elderly. Strategies for overcoming the impact of stigma and ageism are presented to assist healthcare providers to advocate for geropsychiatric clients. PMID- 9362879 TI - Health care in the new Russia: a western perspective. AB - With the end of the Cold War and establishment of relations with Russia, the opportunity for nurses to meet their Russian colleagues is now available. The authors, with an international group of nurses, visited Russia to learn about their healthcare system and nursing practice. The authors found Russian healthcare system severely lacking in the technology and resources available in other industraialized nations. Within this system, the nurse's role is significantly different from nursing in the American healthcare system. Nurses practice within a system of severe shortages and provide nursing care dependent upon physicians. PMID- 9362880 TI - Perinatal loss: bridging tragedy with hope. PMID- 9362881 TI - Saudi murder case. PMID- 9362882 TI - A challenge to the counselling culture. Interview by Kay Smith. PMID- 9362884 TI - Body talk. PMID- 9362885 TI - Mind the gap. Interview by Roger Bushby. PMID- 9362883 TI - Staying power. PMID- 9362886 TI - Quicker, better, cheaper. PMID- 9362887 TI - A chance to say goodbye. PMID- 9362888 TI - Future developments in nursing practice. PMID- 9362889 TI - Developing excellence in nursing practice and care. AB - In this article, change, innovation and excellence in nursing practice are discussed. The author argues that nurses must take control of the systems they use to deliver patient care before they can successfully implement change and improve practice. PMID- 9362890 TI - Achieving interprofessional working in mental health. AB - Interprofessional collaboration in health care has been high on the political agenda in recent years. However, despite several government reports, progress has been relatively slow. Several structural and organisational challenges need to be addressed, alongside the development of valid research in this field, to accelerate the pace of change. This article describes how interprofessional education, in conjunction with service initiatives, offers a way forward for the development of collaborative practice based on users' and carers' needs. PMID- 9362891 TI - Paediatric benchmarking: a review of its development. AB - In this article the author explains how a benchmarking network for paediatric services was developed. The principles are described and the process for topic selection is discussed. PMID- 9362892 TI - Hepatitis: exploding the myths. AB - This article outlines the foundations of hepatitis infectivity and discusses preventive measures for avoiding cross-infection. The purpose of this article is to enable nurses to be well informed so that patients, their families and social contacts are appropriately advised and any perceived myths associated with the disease are dispelled. PMID- 9362893 TI - To catch a thief, abuser, killer. PMID- 9362894 TI - Pay 1998--nursing shortfall in sight. PMID- 9362895 TI - Pay 1998--down to the nitty-gritty. PMID- 9362896 TI - Broke and bewildered. PMID- 9362897 TI - Putting the issue straight over HIV and breast milk. PMID- 9362898 TI - Sacred spaces. PMID- 9362899 TI - Pay 1998--what do you pay to work? PMID- 9362900 TI - Humane decisions. PMID- 9362901 TI - Rationing: a dangerous game. PMID- 9362902 TI - Balanced mix. PMID- 9362903 TI - Day surgery--home economics. Interview by Barbara Millar. PMID- 9362905 TI - Nurse or midwife? PMID- 9362904 TI - Blood pressure measurement equipment. PMID- 9362906 TI - Assessing pain: a vital part of nursing care. AB - Adequate pain relief cannot be achieved without professionals understanding how the pain affects the individuals concerned. This second of six weekly articles looks at how to deal effectively with pain. It considers issues of assessment and proposes a three-part model: always believe the patient, assess pain accurately using a reliable tool, and ask patients how they understand their pain. Next week's article will examine how patients' characteristics influence pain assessment. PMID- 9362907 TI - Providing children with health information. PMID- 9362908 TI - A successful bladder retraining program. PMID- 9362909 TI - Diabetes in Asian communities. PMID- 9362910 TI - Students--do we fail those who fail? PMID- 9362911 TI - Students--the big squeeze. PMID- 9362912 TI - Students--speaking out. PMID- 9362914 TI - Loss is a powerful teacher. PMID- 9362913 TI - Students--power of the union. PMID- 9362915 TI - Take steps to assess the quality of cancer information on the Internet. PMID- 9362916 TI - Pain assessment. AB - Pain assessment is fundamental to planning pain relief and is an area of nursing accountability. It allows diagnosis of the cause of pain, accurately evaluates the effect of analgesia and provides a framework for the setting of standards. Pain assessment should be a collaborative process involving the patient. PMID- 9362917 TI - A pharmacological approach to acute pain. AB - A wide variety of analgesic drugs and techniques is available for the management of acute pain. Nurses are frequently expected to make choices in analgesic therapy. A good understanding of the actions of available drugs is needed by nursing and medical staff to provide optimum pharmacological pain relief. Education of health professionals is essential to promote the effective management of acute pain. PMID- 9362918 TI - A non-pharmacological approach to chronic pain. AB - Non-pharmacological methods are often used in chronic pain. Research on non pharmacological techniques is often poorly designed. PMID- 9362919 TI - [Genetic testing--the possible outcomes]. PMID- 9362920 TI - [Pension fund for nurses--no to ethical regulation clause. Interview by Martin Vestergaard]. PMID- 9362921 TI - [Consumer research--the patient's perspective is closed territory. Interview by Susan Bloch Kjeldsen]. PMID- 9362922 TI - [Locked-in syndrome--wrote a book with his left eye]. PMID- 9362923 TI - [Patient complaint tribunal--61 complaints about nurses]. PMID- 9362924 TI - [Nursing care--when the dying are close to you]. PMID- 9362925 TI - [Health administration--current report on preventive health system for children and youth]. PMID- 9362926 TI - [Romania--a system in a world of difference]. PMID- 9362927 TI - [Romania--a squeeze sector]. PMID- 9362928 TI - [Romania--they pay the price. Interview by Dorthe Nerving]. PMID- 9362929 TI - [Romania--they promote the profession. Interview by Dorthe Nerving]. PMID- 9362930 TI - [Explanation of the mustine saga]. PMID- 9362931 TI - [Psychiatry--more money for the mentally ill]. PMID- 9362933 TI - [Budgets--more money to hospitals]. PMID- 9362932 TI - [Budgets--improved control of economics]. PMID- 9362934 TI - [Psychiatric report--reform for 4 billion krone per year?]. PMID- 9362936 TI - [Viewpoint from the foot therapist. Interview by Marit Fonn]. PMID- 9362935 TI - [Subcutaneous injections--not for nursing assistants. Interview by Kjell Arne Bakke]. PMID- 9362937 TI - [Cancer--it is good to talk it out!. Interview by Erik Dahl]. PMID- 9362938 TI - [Spotlight on cancer care]. PMID- 9362939 TI - [Close-up of: Chim Kong--an innocent victim. Interview by Kari Anne Aase]. PMID- 9362940 TI - [Education--more study places are needed. Interview by Tone Kristiansen]. PMID- 9362941 TI - [Education--finally finished!. Interview by Kari Anne Aase]. PMID- 9362942 TI - [My workplace: Orthopedic Department Vestfold Central Hospital, Tonsberg--among hips, knees and prostheses. Interview by Erik Dale]. PMID- 9362943 TI - [The job is more important than wages. Interview by Kjell Arne Bakke]. PMID- 9362944 TI - [From bygone days--examination questions]. PMID- 9362945 TI - [Neurofibromatosis--easy to see, easy to overlook. Interview by Kjell Arne Bakke]. PMID- 9362947 TI - [Drugs--team work in patient discharge]. PMID- 9362946 TI - [Health policy--lines gathered in action plan. Interview by Kari Anne Aase]. PMID- 9362948 TI - [Education--nurse and therapist. Interview by Erik Dale]. PMID- 9362949 TI - [Bosnia--a year in NATO service]. PMID- 9362950 TI - [Professional Ethics Council--spiritual dimension in nursing services]. PMID- 9362951 TI - [Education--basic work and care should come first]. PMID- 9362952 TI - [Education--an informative and challenging instruction method]. PMID- 9362953 TI - [Care for the aged--many elderly get assistance and care]. PMID- 9362954 TI - [Children and health--health visitors' challenges in a multicultural society]. PMID- 9362955 TI - [The fight against tuberculosis begins in the laboratory. Multiresistant bacteria grow there. Interview by Elisabet Forslind]. PMID- 9362956 TI - [3 million die from tuberculosis every year]. PMID- 9362957 TI - [Does coughing mean tuberculosis?]. PMID- 9362958 TI - [An older well-known Efva returns with power--from nursing to industrial inspection. Interview by Kalle Norberg]. PMID- 9362959 TI - [Our knowledge is not sufficient in practice--immigrant nurses fail test. Interview by Anders Olsson]. PMID- 9362960 TI - [This is an absurd situation--new regulations for certification gets criticism. Interview by Anders Olsson]. PMID- 9362961 TI - [Survey learns nothing from dissatisfaction with health care. Interview by Anders Olsson]. PMID- 9362962 TI - [Equipped for the new jobs?]. PMID- 9362963 TI - [Doctor Gormander jokes about health care research]. PMID- 9362964 TI - [More "dream team" in health care]. PMID- 9362966 TI - [Jyoti weaves a web of contacts among EU's leaders. Interview by Kaj Nyman]. PMID- 9362965 TI - [Norwegian emergency medic first at place of accident. Interview by Tomas Nilsson]. PMID- 9362968 TI - [Talk about a picture. Interview by Christina Fagerstrom]. PMID- 9362967 TI - [Patient drowned--nurse acquited]. PMID- 9362969 TI - [Care in child and adolescent psychiatry. The salutary perspective emphasizes health factors]. PMID- 9362970 TI - [Instrument helps patient to put pain into words. Interview by Birgitta Dalenstam]. PMID- 9362971 TI - [Insulin pen is not good for everyone. Interview by Brit-Infer Nord]. PMID- 9362972 TI - [Health care is not only a nurse's subject. Interview by Anders Olsson]. PMID- 9362974 TI - Controlled clinical trials of anything in myasthenia gravis. PMID- 9362973 TI - Creutzfeldt-Jakob disease in a prolific blood donor. PMID- 9362975 TI - Subcortical reflex myoclonus? PMID- 9362976 TI - The quality of neurological care, 1997. PMID- 9362977 TI - Measuring quality of care in neurology. AB - Neurologists are being asked to incorporate methods into daily practice that measure quality of care. Standards of care are increasingly being defined using evidence-based assessments of neurological literature. To evaluate quality of care, a widely accepted and useful model considers the structure, process, and outcomes of care. Outcomes, the impact of care on patients' health, should include measures of mortality, morbidity, disability, patient functioning and well-being (health-related quality of life), and patient satisfaction with care. A variety of private organizations and government programs exist to encourage documentation and promotion of high quality of care. This explosion in quality information is not yet standardized, so that much confusion exists about appropriate data elements to be measured. The challenge is to collect, summarize, and disseminate practical data useful to neurologists and the purchasers and consumers of our services. PMID- 9362978 TI - Quality of care in academic neurology departments. AB - In striving to improve the quality of patient care, today's academic neurology department faces special problems. Factors that are inherent in the department's broader academic mission and in the organization of a major teaching hospital can compromise practice efficiency, reduce ease of access, and undermine cost competitiveness. However, the same environment also provides the opportunity to exploit areas of unique clinical expertise, create value-added services, and develop regional approaches to service-line integration and disease management strategies. A major challenge for the academic department is to validate the quality and efficiency of its current services while assuming a leadership role in the development of new approaches to quality improvement. This challenge must be met without losing sight of the department's equally important parallel commitments to research and education. PMID- 9362979 TI - Quality of neurological care. Balancing cost control and ethics. AB - As the quality of neurological care becomes a mutual objective of physicians, patients, and health planners, increased demands on cost savings will create conflicts that could threaten the ethical basis of medical practice. Physicians will see increasing ethical conflicts between their fiduciary duties to make treatment decisions in the best interest of their patients and their justice based duties to conserve societal resources. These conflicts can be best mitigated if physicians maintain their orientation as patient advocates but practice cost-conscious clinical behaviors that consider the cost-effectiveness of tests and treatments and do not squander society's finite resources by ordering medical tests and treatments of zero or marginal utility. Health system planners should resolve their conflicting objectives of quality and cost control by rigorously defining and measuring quality through physician leadership and by implementing cost-control measures that enhance the quality of medical care. Managed care organizations voluntarily should forsake financially successful but blatantly unethical cost-saving schemes, such as gag clauses and end-of-year kickback payments to physicians, because these schemes diminish patients' trust in physicians and degrade the integrity of the patient-physician relationship. State and federal laws should prudently regulate these unethical cost-saving schemes to the same extent as they have for the harmful conflicts in fee-for service medicine. PMID- 9362981 TI - Assessing quality of care. The limitation imposed by Condorcet paradox. AB - Condorcet paradox can be used to illustrate the mathematical impossibility of consistently ranking societal choices that are based on individual values. Quality-of-care measures reflect the values and interests of individuals (for example, physicians, patients, and payers) with differing perspectives of health care. Accordingly, appropriate decision making, technical performance, patient satisfaction, outcome, and cost-effectiveness are all valid examples of quality measures. Any attempt to prioritize or combine quality measures should be resisted if Condorcet paradox is to be avoided. The most consistent strategy is to strive to increase quality in each and every facet of its assessment. PMID- 9362980 TI - Managed care and the survival of neurology referral centers. A commitment to centers of excellence. AB - Since the collapse of federal health system reform legislation in 1994, there has been a growing concern with the quality of care provided within managed care systems. Just as physicians practicing under a traditional fee-for-service payment base have financial incentives to do as much as possible for each patient (doing well by doing good), physicians working for managed care plans are sometimes given perverse incentives to do as little as possible. A major quality related concern among patients and payers (often referred to jointly and ambiguously as consumers of care) is the much larger role assigned to primary care physicians in managed care plans than is usually the case with traditional indemnity insurance. PMID- 9362982 TI - Early cognitive and motor symptoms in identified carriers of the gene for Huntington disease. AB - OBJECTIVE: To study early motor and cognitive symptoms in Huntington disease. DESIGN: A follow-up cohort study after a DNA test procedure in which gene carriers and noncarriers were identified among people genetically at risk for Huntington disease. SETTING: Leiden University Medical Center, Department of Neurology, Leiden, the Netherlands, in cooperation with the Clinical Genetics Center Leiden and the Department of Medical Psychology and Psychotherapy, Erasmus University Rotterdam, Rotterdam, the Netherlands. PARTICIPANTS: Thirty-three individuals: 9 unaffected gene carriers, 6 gene carriers with motor symptoms, and 18 noncarriers of the gene for Huntington disease. MAIN OUTCOME MEASURES: A neuropsychologic examination covering a broad area of cognitive functioning, reaction time procedures, and motor tasks. RESULTS: The neuropsychologic assessment showed no significant differences between presymptomatic gene carriers and noncarriers. Three motor tasks differentiated between these 2 groups on a liberal .05 P level (analysis of variance followed by the Student test). The affected gene carriers performed less well than the presymptomatic gene carriers and the noncarriers in 10 motor tasks and 7 cognitive tasks. These differences were significant at P < .05. CONCLUSION: Motor symptoms play a more prominent and unequivocal role than cognitive symptoms in early stages of Huntington disease. PMID- 9362983 TI - Prognostic significance of coexistent bulky metastatic central nervous system disease in patients with leptomeningeal metastases. AB - OBJECTIVE: To assess the clinical significance of bulky metastatic central nervous system disease in patients with leptomeningeal metastases. PATIENTS AND METHODS: Forty patients (24 women and 16 men) ranging in age from 32 to 74 years (median, 56.5 years) with cytologically documented leptomeningeal metastases were demonstrated by cranial or spinal magnetic resonance imaging to have either no bulky central nervous system metastatic disease (group A; 20 patients) or bulky central nervous system metastatic disease (group B; 20 patients). Twenty-nine patients were treated with involved-field radiotherapy, and all patients were treated with sequential intraventricular chemotherapy. RESULTS: Median survival was 7 months in group A (range, 5-12 months) as compared with 4 months in group B (range, 2-12 months) (P < .01; Mantel-Cox log rank analysis). Cause of death was similar in both patient groups. CONCLUSIONS: In patients with leptomeningeal metastases, neuroradiographic demonstration of bulky metastatic central nervous system disease independently predicts survival and is useful in determining which patients are candidates for intraventricular chemotherapy. PMID- 9362984 TI - Does daily aspirin diminish severity of first-ever stroke? AB - BACKGROUND: There are still uncertainties about aspirin efficacy in first-ever ischemic stroke prevention. Also it is unknown whether the severity of first ischemic stroke can be modified by aspirin pretreatment. OBJECTIVE: To analyze a series of patients who had their first ischemic stroke while taking aspirin to evaluate the ability of aspirin prophylaxis to diminish the severity of first ever ischemic stroke. DESIGN: Case-control study. SETTING: Tertiary medical center to which patients were referred. PATIENTS: All consecutive patients admitted to the Tel Aviv Medical Center, Tel Aviv, Israel, from May 1988 through May 1994 because of first-ever ischemic stroke were divided into 2 groups according to aspirin use before stroke: aspirin-treated and non-aspirin-treated groups. MAIN OUTCOME MEASURES: Stroke severity was defined according to activities of daily living within 24 hours after admission: (1) mild stroke, with independence in activities of daily living; (2) moderate stroke, with partial dependency; and (3) severe stroke, with complete dependency. Using chi 2 test, stroke severity was compared between patients taking aspirin before their stroke and non-aspirin-treated patients. RESULTS: Among 2113 consecutive patients with first-ever ischemic stroke, 125 patients had already been taking 100 to 500 mg of aspirin daily. Aspirin-treated and non-aspirin-treated patients did not differ in stroke severity. Mortality was lower in aspirin-treated patients (7.9%) than in non-aspirin-treated patients (12%), but this difference was not statistically significant (P = 17). CONCLUSIONS: We conclude that aspirin as primary prevention treatment has no significant protective effect on severity of first-ever ischemic stroke. The diminution of mortality after first ischemic stroke in patients who had used aspirin should be investigated further. PMID- 9362985 TI - Post-Lyme syndrome and chronic fatigue syndrome. Neuropsychiatric similarities and differences. AB - BACKGROUND: Patients with chronic fatigue syndrome (CFS) and post-Lyme syndrome (PLS) share many features, including symptoms of severe fatigue and cognitive difficulty. OBJECTIVE: To examine the neuropsychiatric differences in these disorders to enhance understanding of how mood, fatigue, and cognitive performance interrelate in chronic illness. METHODS: Twenty-five patients with CFS, 38 patients with PLS, and 56 healthy controls participated in the study. Patients with CFS met 1994 criteria for CFS and lacked histories suggestive of Lyme disease. Patients with PLS were seropositive for Lyme disease, had met the Centers for Disease Control and Prevention criteria, or had histories strongly suggestive of Lyme disease and were experiencing severe fatigue that continued 6 months or more following completion of antibiotic treatment for Lyme disease. All subjects completed self-report measures of somatic symptoms and mood disturbance and underwent neuropsychological testing. All patients also underwent a structured psychiatric interview. RESULTS: Patients with CFS and PLS were similar in several somatic symptoms and in psychiatric profile. Patients with CFS reported more flulike symptoms than patients with PLS. Patients with PLS but not patients with CFS performed significantly worse than controls on tests of attention, verbal memory, verbal fluency, and motor speed. Patients with PLS without a premorbid history of psychiatric illness did relatively worse on cognitive tests than patients with PLS with premorbid psychiatric illness compared with healthy controls. CONCLUSIONS: Despite symptom overlap, patients with PLS show greater cognitive deficits than patients with CFS compared with healthy controls. This is particularly apparent among patients with PLS who lack premorbid psychiatric illness. PMID- 9362987 TI - Characteristics and determinants of sumatriptan-associated chest pain. AB - BACKGROUND: Serious cardiac adverse reactions, including myocardial infarction, have been attributed to the antimigraine drug sumatriptan succinate. Chest pain is considered to be a relatively common adverse reaction to sumatriptan. DESIGN: Postmarketing study. PATIENTS AND METHODS: The study was a part of a national cohort study on adverse reactions to sumatriptan, which was performed with the assistance of drug-dispensing general practitioners in the Netherlands. After data were collected on observed adverse reactions, the patients received a second questionnaire, with specific questions regarding the adverse event, and questions regarding medical history, other health complaints, and smoking habits. Furthermore, they had a physical examination and a blood cholesterol measurement. RESULTS: A total of 137 patients with chest pain associated with intake of sumatriptan were identified and compared with 229 consumers of sumatriptan without this adverse reaction. After multivariate analysis, young age, hypertension, general complaints of abdominal pain, and a family history of myocardial infarction were associated with an increased risk of chest pain attributed to sumatriptan. Hypertension in particular was a risk factor for sumatriptan-induced chest pain in men (relative risk, 8.0; 95% confidence interval, 1.8-40) compared with hypertension as a risk factor in women (relative risk, 1.63; 95% confidence interval, 0.9-3.1). CONCLUSIONS: Young age, hypertension, general complaints of abdominal pain, and a family history of myocardial infarction are associated with an increased risk of chest pain attributed to sumatriptan. Sex is an effective modifier of risk factors of sumatriptan-induced chest pain. In particular, hypertension is a strong risk factor in men. PMID- 9362986 TI - Persistent vegetative state in Alzheimer disease. Does it exist? AB - OBJECTIVE: To determine if the published criteria for diagnosis of the persistent vegetative state could be applied to patients suffering from Alzheimer disease. DESIGN AND METHODS: Eighty-eight institutionalized patients with a diagnosis of possible or probable Alzheimer disease were evaluated for the presence of persistent vegetative state. Initial screening excluded patients who were able to do any of the following: feed themselves, respond to command, walk, or maintain continence of bowel and bladder. A sample of 12 of 28 patients unable to perform any of these functions was examined independently by 3 of us. RESULTS: During the first examination, 2 patients were diagnosed as being in a vegetative state by 2 of us and 3 additional patients by 1 of us. One of us did not diagnose any patient as being in a vegetative state. A second evaluation of the same patients was performed 2 months later, after holding a consensus meeting to standardize the evaluation procedure. During the second evaluation, the vegetative state was diagnosed in 6 patients but only by 1 of us. CONCLUSION: The diagnostic disagreement between the neurologists indicate that Alzheimer disease may only rarely progress to the persistent vegetative state. PMID- 9362988 TI - Exclusion of elderly subjects from clinical trials for Parkinson disease. AB - OBJECTIVES: To determine whether subjects older than 75 years are included in the randomized controlled trials of antiparkinsonian medications conducted during the last 30 years and to identify study characteristics that are associated with the exclusion of patients of advanced age. METHODS: A systematic search was conducted on MEDLINE from January 1966 until September 1996 of all randomized controlled trials of drugs used to treat the motor symptoms of Parkinson disease. Articles were abstracted for the age of subjects date of publication, geographic location, drug class studied, stage of Parkinson disease of subjects, and the number of subjects in each trial. RESULTS: One hundred twelve articles met the inclusion criteria. The weighted mean (+/- SD) age for subjects in all trials was 62.2 +/- 3.9 years. Forty-two studies (37.5%) included subjects older than 75 years. However, in 31 articles (27.7%) it could not be determined if subjects older than 75 years were included. Among the 8 studies that provided the actual number of subjects within specific age groups, only 8 (5.5%) of 145 subjects were older than 75 years. Publication in the last decade was significantly associated with a decreased likelihood of including subjects older than 75 years (odds ratio, 0.19; 95% confidence interval, 0.06-0.62). CONCLUSIONS: The relatively small number of subjects older than 75 years included in controlled trials of antiparkinsonian drugs seriously impedes our understanding of the efficacy and safety of these drugs in a large subgroup of frail patients for whom these products are prescribed. The tendency to exclude subjects of advanced age is highest in the most recently published articles that study new advances in pharmacotherapy. There is inadequate reporting of the age characteristics of subjects in clinical trials. This limitation hinders the synthesis of data regarding drug efficacy and toxicity relevant to older age groups. PMID- 9362989 TI - Education and other measures of socioeconomic status and risk of incident Alzheimer disease in a defined population of older persons. AB - OBJECTIVE: To assess the relations of 3 measures of socioeconomic status (education, occupational prestige, and income) to risk of incident clinically diagnosed Alzheimer disease (AD). DESIGN: Cohort study with an average observation of 4.3 years. SETTING: East Boston, Mass. a geographically defined community. PARTICIPANTS: A stratified random sample of 642 community residents 65 years of age and older who were free of AD at baseline. MAIN OUTCOME MEASURE: Clinical diagnosis of probable AD according to standard criteria, using structured uniform evaluation. RESULTS: The relations of the 3 measures of socioeconomic status to risk of disease were assessed using logistic regression analyses. In individual analyses, fewer years of formal schooling, lower income, and lower occupational status each predicted risk of incident AD; risk of disease decreased by approximately 17% for each year of education. In an analysis including all 3 measures, the effect of education on risk for disease remained approximately the same, but the effects of the other 2 measures were somewhat less and did not attain formal statistical significance, compared with separate analysis of each measure. CONCLUSIONS: Markers of lower socioeconomic status predict risk of developing incident AD. The mechanism of this relation is uncertain, but the possibility that it reflects unidentified and potentially reversible risk factors for the disease deserves careful investigation. PMID- 9362990 TI - An update on primary drug therapies for Alzheimer disease. AB - Propelled by remarkable advances in the understanding of the pathological characteristics of Alzheimer disease (AD), the prospects for the treatment of the clinical disorder have brightened considerably in the past decade. Primary treatment is aimed at the core elements of AD: memory and other cognitive loss at the symptomatic level and the pathological characteristics of molecular, cellular, and neural systems at the biological level. Behavioral features, such as depression, delusions, anxiety, disordered sleep, and agitation, are considered secondary manifestations of AD, although these features have a major impact on the quality of life, functional effectiveness, and caregiver burden. The focus of this review is on recent developments in the primary therapy for AD. PMID- 9362991 TI - Brain magnetic resonance diffusion abnormalities in Creutzfeldt-Jakob disease. AB - BACKGROUND: Magnetic resonance imaging of the brain has been of limited usefulness in the diagnosis of Creutzfeldt-Jakob disease. Abnormalities on T2 weighted images have been described, but these are neither highly sensitive nor specific. OBJECTIVE: To determine whether diffusion-weighted magnetic resonance images might be useful in the evaluation of Creutzfeldt-Jakob disease. CASE PRESENTATION: A 61-year-old woman with rapidly progressive dementia was referred for cranial magnetic resonance imaging. Diffusion-weighted images were obtained as part of the examination. Brain biopsy confirmed the diagnosis of Creutzfeldt Jakob disease histologically. FINDINGS AND CONCLUSIONS: The diffusion-weighted magnetic resonance brain images demonstrated bilaterally symmetrical marked increase in signal intensity in the caudate nuclei, putamina, thalami, cingulate gyri, and right inferior frontal cortex. The apparent diffusion coefficient map showed abnormally low diffusion in these regions (as low as 40% of normal in the caudate head). This suggests that there is restricted diffusion in these regions. The T2-weighted images demonstrated slightly increased signal bilaterally in the caudate nuclei and putamina. These findings indicate that diffusion magnetic resonance imaging might be a sensitive means of imaging the abnormalities seen in Creutzfeldt-Jakob disease. PMID- 9362992 TI - Hemiparetic acute myopathy of intensive care progressing to triplegia. AB - OBJECTIVE: To describe a unique case of acute asymmetrical myopathy following high-dose intravenous use of corticosteroids that initially mimicked a stroke and then evolved into a picture suggestive of myelopathy. DESIGN: Case report. SETTING: Tertiary hospital. PATIENTS: A 71-year-old woman treated with high-dose steroids for an acute asthmatic exacerbation developed acute hemiparesis that progressed to triplegia without evidence of central nervous system involvement. RESULTS: Nerve conduction studies, electromyography, and muscle biopsy revealed the typical features of necrotizing myopathy with loss of thick filaments. CONCLUSIONS: This case demonstrates that high-dose corticosteroid therapy can induce asymmetrical myopathic weakness. Hemiplegia evolving to triplegia in a setting of corticosteroid treatment could potentially misdirect the diagnosis toward a lesion of the brain or spinal cord. When a central nervous system abnormality cannot be demonstrated a search for a peripheral abnormality, such as myopathy, is warranted. PMID- 9362993 TI - Frontotemporal degeneration, Pick disease, and corticobasal degeneration. One entity or 3? 3. PMID- 9362994 TI - Frontotemporal dementia, Pick disease, and corticobasal degeneration. One entity or 3? 1. PMID- 9362995 TI - Frontotemporal degeneration, Pick disease, and corticobasal degeneration. Three entities or 1? PMID- 9362996 TI - Motor unit action potentials recorded with concentric electrodes: physiologic implications. AB - Computer simulations of concentric needle electrode recording characteristics assume a hemisphere spatial recording territory for the electrode's core with the cannula shielding electrical activity arising from those muscle fibers located behind the cannula with respect to the electrode's core. It is also believed that the motor unit action potential's (MUAP) duration is generated by the number of muscle fibers within the electrode's hemispherical recording territory. This presumption suggests that rotating the needle will necessarily alter the number of muscle fibers within the hemispherical recording territory and hence lead to an alteration in MUAP duration. Comparisons were performed for different needle orientations with documentation of no statistically significant alteration in MUAP duration. Additionally, referential recording montages with the concentric needle electrode revealed that the electrode's core records MUAPs with durations comparable to those detected by the cannula. These findings strongly suggest that the recording territory of the concentric needle electrode, with respect to MUAP duration, is not a hemisphere but a sphere encompassing most if not all of the MUAP's muscle fibers in a manner similar to that of a monopolar needle. These findings have significant implications regarding presently used MUAP simulation techniques and require a reconceptualization of how the concentric needle electrode records electrical activity within a volume conductor. PMID- 9362997 TI - Stimulus/response curves as a method of measuring motor cortical excitability in man. AB - We investigated whether input/output curves of human motor cortex could provide similar information to cortical mapping under two conditions where the motor maps are known to change dramatically: ischaemic anaesthesia and amputation. Stimulus/response curves were constructed by recording the size of EMG responses evoked in arm muscles with transcranial magnetic stimulation at a single site using a range of intensities. Changes in the slope of this relationship during ischaemic anaesthesia (6 normal subjects) or amputation (two patients) were compared to changes in cortical motor maps produced by stimulating different sites at the same intensity. At rest both interventions increased map areas, as well as the slope of the stimulus/response curves. During voluntary activity they had no effect. We conclude that stimulus/response curves can detect changes in cortical motor maps, and discuss potential mechanisms for this effect. PMID- 9362998 TI - Topographic mapping of trans-cranial magnetic stimulation data on surface rendered MR images of the brain. AB - We present a method for the coregistration and topographic mapping of trans cranial magnetic stimulation (TCMS) data on surface rendered images of the cortex, derived from Magnetic Resonance Images (MRI). We describe the TCMS procedure and the methods used to locate the TCM stimulation sites in the MRI coordinate system, and the algorithms needed to depict the TCMS distribution as a pseudocolour contour map on the cortical surface. The methods are validated using TCMS data from the hand (thenar) and leg (tibialis muscle). The methods used correctly depict the expected motor representations of each of these areas and we therefore propose that this technique may be used as a functional imaging tool in the investigation of cortical function in both normals and patients. PMID- 9362999 TI - Post-exercise depression of motor evoked potentials as a function of exercise duration. AB - Post-exercise facilitation and post-exercise depression are phenomena described in motor evoked potentials (MEPs) elicited to transcranial magnetic stimulation. Brief, non-fatiguing muscle activation produces post-exercise facilitation, and prolonged fatiguing muscle activation produces post-exercise depression. We studied 12 normal subjects to determine whether post-exercise depression occurs before fatigue is reached. We recorded MEPs from the resting extensor carpi radialis muscle after increasing the duration of isometric wrist extension, at 50% of maximum voluntary contraction, until the muscle fatigued. Fatigue was defined as the inability to maintain that force. The mean exercise duration before the muscle fatigued was 130 s, and post-exercise depression occurred only beyond 90 s of exercise. We conclude that post-exercise depression is detectable only after prolonged muscle activation. PMID- 9363000 TI - Facilitation of motor evoked potentials after repetitive voluntary hand movements depends on the type of motor activity. AB - Recent neurophysiological studies suggest that repetitive execution of identical movements is crucial for motor learning. During and after repetitive motor action, changes in motor cortical excitability have been demonstrated by means of transcranial magnetic stimulation. Nevertheless, the frequency and intensity of movement repetition that are necessary to achieve an optimal improvement in motor function are unknown. Fourteen healthy volunteers participated in the present study, which deals with the post-exercise facilitatory and/or inhibitory effects of 5 different motor conditions, including repetitive isotonic contractions at the wrist at two different velocities and two different forearm positions, a sustained isometric hand extension and repetitive hand extensions at the wrist induced by means of transcutaneous electrical muscle stimulation. The modification of muscular response potentials in the extensor carpi radialis muscle was measured following the various motor tasks and the electrical muscle stimulation. The only statistically significant facilitatory effect was observed following an extension-relaxation task at low frequency. Furthermore, the duration of transcranially induced silent periods showed a significant reduction after this motor task. PMID- 9363001 TI - The volitional unit: a functional concept in cortico-motoneuronal connections in humans. AB - We used the EMG precision decomposition technique to resolve complex EMG signals and derive information about the firing times of a family of motor units (MUs) and the force they produce. The active units shared a common behavior among their firing rates, a concept described by DeLuca et al. and termed the 'common drive'. This 'common' behavior was extracted as the average of the firing rates of MUs and found to track the subject's force trajectory. In this paper, we propose the existence of functional cortico-motoneuronal connections which provide for a large number of combinations between affector cortical motoneurons (CMNs) and effector spinal motoneurons (SMNs) for the generation of a purposeful movement. We argue that these connections provide the essential link between volition and movement and function as a 'volitional unit' which consists of the CMNs, the SMNs and the anatomical and interneuronal connections between them. PMID- 9363002 TI - Concentric/monopolar needle electrode modeling: spatial recording territory and physiologic implications. AB - Scaled 20:1 physical models of monopolar and standard concentric needle electrodes are investigated with a constant current bipolar generator to determine the amplitude versus radial distance characteristics of these two electrodes. Each model is examined at three scaled and simulated tissue penetration depths (4, 10 and 20 mm) with measurements documented from 20 to 9000 microns radially in front and behind the models. The monopolar compared to concentric electrode has a smaller response to a standardized stimuli but a flatter response curve at distances of less than 1500 microns. The cannula of the concentric needle also has a flatter response than that of its core. When compared to a remote reference such as that at scaled depths of tissue penetration approximating 4 mm or less the cannula-to-remote reference potential exceeds the amplitude of the core-to-remote reference, recording a net negative potential at 6500 microns in front and 3500 microns behind the core. This study offers an explanation for the clinically observed larger magnitude potentials detected with monopolar compared to concentric electrodes resulting from a larger recording cross-sectional area with more fibers contributing to the potential even though the magnitude of potential at any one location is comparatively smaller in magnitude than that for the concentric electrode. Additionally, the physiologic duration of a motor unit is anticipated to be considerably longer than presently measured clinically with automated methods because of the electrodes' ability to detect such small signals from a large region of the volume conductor. PMID- 9363003 TI - Peak-ratio interference pattern analysis in the detection of neuromuscular disorders. AB - Peak-ratio interference pattern analysis (peak-ratio method) is said to have a high sensitivity and to be independent of sex and age. This study was carried out to prove or disprove these findings. The peak-ratio method and qualitative motor unit action potential (MUAP) analysis were applied to the right brachial biceps and anterior tibial muscles of 44 healthy subjects, aged 23-87 years, 25 neuropathy patients, aged 21-83 years, and 29 myopathy patients, aged 19-70 years. Peak-ratio parameters were independent of sex and age. They tended to be lower in the anterior tibial muscle than in the brachial biceps muscle. Neuropathy patients typically showed decreased peak-ratio, short time intervals and increased amplitude/turn. Myopathy patients typically showed increased peak ratio, turns/s and short time intervals. The sensitivity of the peak-ratio method was 72% for neuropathy patients and 59% for myopathy patients. The sensitivity of the peak-ratio method was similar to that of the MUAP analysis in neuropathy patients and higher than that of the MUAP analysis in myopathy patients. The specificity of the peak-ratio method was 80%. The peak-ratio method proved to be a valuable, supplementary electromyographic tool for the detection of neuromuscular disorders. PMID- 9363004 TI - The influence of active electrode placement on CMAP amplitude. AB - The compound muscle action potential (CMAP) is a measure of the number of axons in a nerve. Placement of the active recording electrode over the motor point of a muscle is thought to give the maximal response, but there is considerable variation in amplitude among initially negative CMAP wave forms. Ten examiners of varied training backgrounds and experience placed the active electrode as they usually do over the thenar, hypothenar, abductor hallucis, and extensor digitorum brevis muscles in the same normal subject. There was variability of the CMAP amplitude recorded over each muscle; the lowest value recorded from a muscle was 57% of the maximum value, and the lowest median value was 77%. There was no relation between examiner background or level of training and recording the maximal response. Higher amplitude CMAPs were associated with steeper wave form slopes, but the range of correlations between amplitude and slope was 0.42 to 0.92. We conclude that when it is important to record the maximal CMAP response, empirical assessment by moving the active electrode is necessary. PMID- 9363005 TI - Cortical mechanism underlying externally cued gait initiation studied by contingent negative variation. AB - In order to clarify the cortical mechanism underlying gait initiation, we examined the scalp distribution of the contingent negative variation (CNV) preceding externally cued gait initiation in a simple reaction-time paradigm in 10 healthy right-handed men, and compared the results with the CNV preceding simple foot dorsiflexion. A pair of auditory stimuli was given with an interstimulus (S1-S2) interval of 2 s and gait consisting of at least 3 steps was initiated with the right footstep as fast as possible in response to S2. Brisk dorsiflexion of the right foot was employed as a control task. It was found that the late CNV in the gait initiation task started about 1 s before S2, and was largest at Cz (-9.3 +/- 3.1 microV) without clear asymmetry over the scalp. However, it was ill defined in the parietal area. In the foot dorsiflexion task, the late CNV was maximal at Cz (-7.1 +/- 2.9 microV), and clearly seen also over the parietal area. The late CNV at Cz was significantly (P < 0.01) larger in the gait initiation than in the simple foot dorsiflexion. The amplitude of the late CNV preceding the foot dorsiflexion task was not significantly different between the sitting and the standing posture. In view of the results of previous invasive studies in both humans and animals which showed some frontal areas, including the supplementary motor area (SMA) and the primary motor cortex, as the generators of the late CNV, it is suggested that the cerebral cortex is active in initiation of externally triggered gait in a different way from the simple foot movement, and that bilateral SMAs may play a more important role in gait initiation than in simple foot movement. PMID- 9363006 TI - Leg muscle activation during gait in Parkinson's disease: influence of body unloading. AB - The effect of body unloading (75, 50 and 25% of body weight) on upper and lower leg muscle activation during stepping on a treadmill was investigated in groups of patients with Parkinson's disease and age-matched healthy subjects. The aim of the study was to test the hypothesis that impaired extensor load receptor function exists in the patients. A strong load sensitivity was found for the gastrocnemius (GM) electromyographic (EMG) activity (i.e. EMG amplitude decreased with unloading during stepping in both groups of subjects). The change in the EMG amplitude of the rectus femoris was less dependent upon the load but was observed to be more pronounced in the patients. Upper and lower leg flexor muscles were relatively load-insensitive. The absolute GM EMG amplitude during the stance phase of stepping with normal body loading was significantly smaller in the patients than in the healthy subjects. It is suggested that the latter observation is due to a change in the threshold or bias of the extensor load reflex mechanism in the patients. The slope or gain of this reflex appears to be preserved. PMID- 9363007 TI - Importance of soft tissue inhomogeneity in magnetic peripheral nerve stimulation. AB - In magnetic peripheral nerve stimulation with a figure-of-eight coil, a 'tangential-edge' coil orientation (the nerve is beneath the coil intersection and perpendicular to the coil wings) is ideal theoretically. However, some experimental results show that strong muscle responses are elicited with a 'symmetrical-tangential' coil orientation (the nerve is beneath the coil intersection and parallel to the coil wings), which is inconsistent with the cable theory. We hypothesized that the 10:1 conductivity difference between muscle and fat would cause inconsistent results during magnetic median nerve stimulation in the elbow, which was verified using an inhomogeneous volume conductor model. The induced electric fields were measured in a model composed of saline solutions of different concentrations divided by a cellophane sheet. A nerve was imagined along the boundary between the two solutions, and the coil was held in a 'symmetrical-tangential' position. Virtual cathodes, which were off the nerve in the homogeneous model, were on the nerve in the inhomogeneous model. The previous inconsistent results were explained by considering soft tissue inhomogeneity without any modification of the assumption in the cable theory that only the induced electric field component parallel to the nerve is responsible for nerve excitation. PMID- 9363009 TI - Incidence and clinical symptoms of Aeromonas-associated travellers' diarrhoea in Tokyo. AB - In a survey examining the causes of travellers' diarrhoea treated in Tokyo between July 1986 and December 1995, Aeromonas species were isolated from 1265 (5.5%) of 23,215 travellers returning from developing countries. Aeromonas species were the fourth most frequent enteropathogen isolated, following enterotoxigenic E. coli (8.5%), Salmonella spp. (7.6%) and Plesiomonas shigelloides (5.6%). Aeromonas species were found in 1191 (5.6%) of 21,257 patients with diarrhoea and in 74 (3.8%) of 1958 healthy individuals without diarrhoea. Mixed infection was observed in 512 (40.5%) cases. No significant difference in the prevalence of Aeromonas by year, season, age distributions, or sex was observed, but a slight difference was noted depending on the country where the travellers visited. Of the 1265 Aeromonas isolates, 893 strains (70.6%) were A. veronii biovar sobria, 330 (26.1%) were A. hydrophila, and 42 (3.3%) were A. caviae. The clinical symptoms of patients from whom Aeromonas species was isolated as the only potential enteric pathogen were almost similar, which were watery diarrhoea (about 60%), abdominal cramps (43%), fever (around 15%), and nausea or vomiting (13%). Although the severity of illness was milder than that of enterotoxigenic E. coli alone, these data suggest that Aeromonas species are important enteric pathogens in travellers' diarrhoea. PMID- 9363008 TI - An outbreak of infection due to verocytotoxin-producing Escherichia coli O157 in four families: the influence of laboratory methods on the outcome of the investigation. AB - Three members of family A, who had diarrhoea on 20 October, lived on a small arable farm which had 10 cattle. Manure from the animals was used to fertilize the ground for growing potatoes which were then offered for retail sale, unwashed, directly from the farm. The mother from family B bought potatoes, which were covered with manure, from family A in early November and over the subsequent 10 days she became ill with diarrhoea and her daughter and son both became ill with bloody diarrhoea. The mother from family C visited family B while the daughter from the latter family was symptomatic; the mother developed diarrhoea several days later. The mother and two sons from family D visited family B while the son from the latter family was symptomatic; the first son developed bloody diarrhoea 6 days later which progressed to development of haemolytic-uraemic syndrome. Direct culture of faecal samples onto cefixime rhamnose sorbitol MacConkey agar failed to isolate E. coli O157 from any of the symptomatic patients, and direct culture onto cefixime tellurite sorbitol MacConkey agar isolated the organism from only one patient. In contrast, a combination of isolation of E. coli O157 by immunomagnetic separation and detection of E. coli O157-specific secretory IgA, suggested E. coli O157 infection in all eight symptomatic patients, but not in any of the family members who were not ill. Two children who excreted the organism for 60 and 89 days respectively were the only two patients who did not develop a secretory IgA response. E. coli O157 was not isolated from potatoes from the farm and faecal samples from the farm animals were not available for examination. The study illustrates the need to use the most sensitive methods available during the investigation and follow up of cases of E. coli O157 infection. PMID- 9363010 TI - Incomplete sanitation of a meat grinder and ingestion of raw ground beef: contributing factors to a large outbreak of Salmonella typhimurium infection. AB - Consumers in the United States continue to eat raw or undercooked foods of animal origin despite public health warnings following several well-publicized outbreaks. We investigated an outbreak of Salmonella serotype Typhimurium infection in 158 patients in Wisconsin during the 1994 Christmas holiday period. To determine the vehicle and source of the outbreak, we conducted cohort and case control studies, and environmental investigations in butcher shop A. Eating raw ground beef purchased from butcher shop A was the only item significantly associated with illness [cohort study: relative risk = 5.8, 95% confidence interval (CI) = 1.5-21.8; case control study: odds ratio = 46.2, 95% CI = 3.8 2751]. Inadequate cleaning and sanitization of the meat grinder in butcher shop A likely resulted in sustained contamination of ground beef during an 8-day interval. Consumer education, coupled with hazard reduction efforts at multiple stages in the food processing chain, will continue to play an important role in the control of foodborne illness. PMID- 9363011 TI - Klebsiella meningitis in Taiwan: an overview. AB - Klebsiella infection has been considered to be an uncommon cause of meningitis. To determine its incidence and clinical features, we reviewed the microbiologic records of cerebrospinal fluid (CSF) and blood cultures and the medical records of patients with bacterial meningitis admitted between 1981 and 1995. Klebsiella meningitis was diagnosed in 79 patients with 83 episodes. All patients had klebsiella isolated from CSF and/or blood and typical symptoms and signs of acute bacterial meningitis. Of these, 74 were over 16 years of age and 2 of the 5 children were infants. There was an increased prevalence rate of klebsiella meningitis after 1986. Of the 83 episodes, only 9 occurred between 1981 and 1986, accounting for 7.8% of 115 cases with CSF and/or blood culture-proven acute bacterial meningitis, whereas in 1987-95, there were 74 episodes accounting for 17.7% of 419 bacteriologically proven cases. K. pneumoniae accounted for 69 episodes, K. oxytoca, 11 episodes and K. ozaenae, 3 episodes. Male gender, diabetes mellitus and liver cirrhosis were commonly associated with K. pneumoniae meningitis. Neurosurgical procedures were frequently associated with K. oxytoca meningitis. All three patients with K. ozaenae meningitis had a primary disease of the nasopharyngeal pathway. The mortality rate due to K. pneumoniae was 48.5%, K. oxytoca, 10% and K. ozaenae, 0%. In patients with K. pneumoniae meningitis, poor prognostic factors included age over 60 years, diabetes mellitus, bacteremia and severe neurological deficits on the first day of treatment. PMID- 9363012 TI - Vibrio furnissii isolated from humans in Peru: a possible human pathogen? AB - During a cholera surveillance programme, Vibrio furnissii was isolated in late January and early February 1994 from stool samples collected from 14 persons of whom six had diarrhoea. The remaining eight persons were healthy family members or neighbours to cholera cases. No common source of infection was found. Strains isolated from stool samples each showed typical biochemical reactions of V. furnissii including gas production. Each isolate, except one, agglutinated O antisera yielding a total of eight different serotypes. Most isolates were sensitive to 10 antibiotics tested, except to ampicillin and the vibriostatic agent O/129 (10 micrograms). Eight of 14 (57%) strains carried plasmids in the size range 2.6-88 kb, however, no correlation was found between antibiotic susceptibility patterns and plasmid content. Altogether, seven closely related HindIII ribotypes were observed among the 14 V. furnissii isolates studied. V. furnissii strains isolated from family members and other persons living close together often showed different ribotypes suggesting that the isolation was not associated with neighbourhood. Serotyping, plasmid profiling and ribotyping revealed a high strain diversity within V. furnissii, however, the importance of V. furnissii as an enteric pathogen remains to be elucidated. PMID- 9363013 TI - Helicobacter pylori in out-patients of a general practitioner: prevalence and determinants of current infection. AB - Data on prevalence and determinants of Helicobacter pylori infection in well defined populations are scarce. We investigated the prevalence and determinants of active H. pylori infection in a population of out-patients attending a general practitioner in Southern Germany. Infection status was determined by [13C]urea breath test. In addition, information on potential risk factors and medical history was collected. Five hundred and one of the 531 eligible patients participated in the study (response rate of 94.4%). In total, 117 of the 501 patients had a positive [13C]urea breath test (23.4%). Prevalence of H. pylori infection increased with age from 10.8% (95% CI 5.7-18.1%) in the age group 15-29 years to 30.8% (95% CI 22.1-40.6%) in the age group 60-79 years and was 20.3%, 30.4% and 28.2% for the age groups 30-39, 40-49 and 50-59 years, respectively. Education and childhood living conditions, especially the number of siblings, were identified as additional independent determinants of infection. PMID- 9363014 TI - Molecular epidemiology of glycopeptide-resistant Enterococcus faecium on a renal unit. AB - The clinical and molecular epidemiology of glycopeptide-resistant Enterococcus faecium was investigated during an outbreak on a renal unit. Forty-nine patients were colonized or infected during a 15-month period. Sites of colonization included faeces, urine, intravenous (IV) catheter tips and wound swabs. Ten patients had infections, which included five bacteraemias and three episodes of peritonitis. Pulsed-field gel electrophoresis of 43 patient isolates of glycopeptide-resistant E. faecium identified seven strains during the first 7 months of the outbreak. Three of these strains affected five or more patients. One strain accounted for 17/43 isolates. Isolates that were possibly related to another renal unit strain were cultured from patients at two other Manchester hospitals. These isolates were epidemiologically-related, and may represent a single Manchester epidemic strain. Of five patients who had multiple isolates of glycopeptide-resistant E. faecium, three had isolates representing a single strain and two were colonized or infected by more than one strain. PMID- 9363015 TI - Antibody levels against Streptococcus pneumoniae and Haemophilus influenzae type b in a population of splenectomized individuals with varying vaccination status. AB - In order to determine antibody levels against Streptococcus pneumoniae (pneumococcus) and Haemophilus influenzae type b (Hib) in a population of splenectomized subjects, 561 persons in a Danish county, splenectomized between 1984 and 1993 were identified. Two hundred and thirty-five were alive and 149 participated in the study. Each person donated a blood sample for antibody determination by ELISA. Though vaccine coverage among the 149 persons was 91% only 52% had 'protective' levels of pneumococcal antibodies. Despite recommendations for regular follow-up on pneumococcal antibody levels this had only been carried out in 4% of the subjects. Splenectomized subjects who needed pneumococcal revaccination were significantly more likely to have received their initial vaccination less than 14 days before or after splenectomy, as recommended, than those not requiring revaccination. Therefore, the timing of initial pneumococcal vaccination in relation to splenectomy seems to be important. All persons had Hib antibody levels higher than 0.15 microgram/ml and 60% had levels higher than 1 microgram/ml, which are the levels thought to provide short term and long term protection, respectively. In total, 37% of the 149 persons tested had pneumococcal and Hib antibody levels thought to correlate with protection from serious infections. PMID- 9363017 TI - The natural history of tuberculosis: the implications of age-dependent risks of disease and the role of reinfection. AB - Many aspects of the natural history of tuberculosis are poorly understood. Though it is recognized that clinical tuberculosis may follow shortly after initial infection ('primary' disease), or many years thereafter through either endogenous reactivation or after reinfection, the relative importance of these mechanisms is often disputed. The issue is complicated by the fact that the risks of developing disease are age-dependent, and reflect infection risks which may change over time. This paper estimates the age-dependent risks of developing tuberculosis using an age-structured deterministic model of the dynamics of tuberculous infection and disease in England and Wales since 1900. The work extends the classical studies of Sutherland and colleagues. The best estimates of the risks of developing 'primary' disease (within 5 years of initial infection) were approximately 4%, 9% and 14% for individuals infected at ages 0-10, 15 years and over 20 years respectively, and a previous infection appeared to impart little protection against (further) reinfection, but 16-41% protection against disease subsequent to reinfection for adolescents and adults. We also provide evidence that reinfection made an important contribution to tuberculous morbidity in the past, as (i) exclusion of exogenous disease from the model considerably worsened the fit to observed notification rates, and (ii) the dramatic decline in the risk of tuberculous infection from 1950 in England and Wales accelerated the decline in morbidity among all individuals, even among the older age groups with a high prevalence of tuberculous infection. We conclude that the risk of infection is the single most important factor affecting the magnitude of the tuberculous morbidity in a population, as it determines both the age pattern of initial infection (and hence the risk of developing disease) and the risk of reinfection. PMID- 9363016 TI - In vitro susceptibility studies and detection of vancomycin resistance genes in clinical isolates of enterococci in Nagasaki, Japan. AB - Glycopeptide resistance in enterococci is now a cause of clinical concern in the United States and Europe. However, details of vancomycin resistance in enterococci in Japan have been unknown. We measured minimum inhibitory concentrations (MICs) of various antimicrobial agents for a total of 218 clinical strains of enterococci isolated in our hospital in 1995-6 in addition to 15 strains with known genotypic markers of resistance. We also screened vancomycin resistance genes using a single step multiplex-PCR. In clinical isolates, only two strains of Enterococcus gallinarum were of intermediate resistance to vancomycin (MIC, 8 micrograms/ml), while the others were all susceptible. Glycopeptides (vancomycin and teicoplanin) and streptogramins (RP 58500 and RPR 106972) showed potent antimicrobial effects for the isolates. In addition, ampicillin was also potent for Enterococcus faecalis, while ampicillin, minocycline and gentamicin were potent for Enterococcus avium. No vanA or vanB genes were detected, while vanC1 and vanC23 genes were detected from two and four strains, respectively. Our results suggest that incidence of VRE in Japan may be estimated as still very low at this time. PMID- 9363018 TI - Immunity to diphtheria in Siena. AB - The aim of this study, carried out in 1993, was to evaluate diphtheria immunity in Siena. Diphtheria antitoxin levels were measured by means of the immunoenzymatic test (ELISA) in serum samples of 602 apparently healthy subjects (239 males and 363 females) of all ages residing in Siena. According to widely used criteria, 6% of the total population were susceptible to diphtheria (antibody levels < 0.01 IU/ml), 71% had basic protection (0.01-0.09 IU/ml) and 23% were fully protected (> or = 0.1 IU/ml). The results suggested that a high proportion of young population had a protective level of immunity against diphtheria, that susceptibility increased with age and a smaller proportion of males (2.9%) than females (8.3%) were unprotected; this difference was statistically significant. Our results suggest that it may be useful to revaccinate adults with low levels of diphtheria toxoid so that the percentage that remains unprotected does not put the community at risk of an outbreak of diphtheria. PMID- 9363019 TI - An economic analysis of varicella vaccination for health care workers. AB - A simulation model was constructed to assess the relative costs and cost effectiveness of different screening and vaccination strategies for dealing with hospital incidents of varicella exposure, compared with current policies, using data from published sources and a hospital survey. The mean number of incidents per hospital year was 3.9, and the mean annual cost of managing these incidents was pounds 5170. Vaccination of all staff would reduce annual incidents to 2.2 at a net cost of pounds 48,900 per incident averted. Screening all staff for previous varicella, testing those who are uncertain or report no previous varicella, and vaccinating those who test negative for VZV antibodies, reduces annual incidents to 2.3 and gives net savings of pounds 440 per incident averted. Sensitivity analyses do not greatly alter the ranking of the options. Some form of VZV vaccination strategy for health care workers may well prove a cost effective use of health care resources. PMID- 9363020 TI - The prevalence of hepatitis B in Sweden; a statistical serosurvey of 3381 Swedish inhabitants. AB - The prevalence of hepatitis B virus markers in the adult Swedish population was investigated according to age, sex, origin and demographic stratum. Sera were collected from 3382 persons in 1990-1. The sera were selected on a statistical basis considered to be representative of the Swedish population from adults aged > or = 18 years. Two of the sera (0.06%) were found to be hepatitis B surface antigen positive. The two hepatitis B carriers were of non-Scandinavian origin as were (8.9%) of those tested. A total of 90 persons had a marker of previous, hepatitis B virus infection, i.e. antibodies against hepatitis B core antigen. Of these, 66 (2.0%) were of Scandinavian origin and 24 (18.1%) from highly endemic areas. The overall hepatitis B virus marker prevalence was 2.7%. The highest age specific prevalence of hepatitis B markers in those of Scandinavian origin was in those born in 1939 and earlier. In this age-group, women had a significantly higher prevalence (3.6%) than males (1.9%). The lowest prevalence was found in those born in 1970 and later. No significant, age-related differences between younger or older persons, or between men and women, could be found in persons of non-Scandinavian origin. The results showed significant differences in exposure to hepatitis B virus among the indigenous population, compared with those of non Scandinavian extraction. The results do not support the proposal to include hepatitis B vaccination in the Swedish immunization schedule. PMID- 9363022 TI - Risk factors for human cysticercosis morbidity: a population-based case-control study. AB - A population-based case-control study to determine social and behavioural risk factors for Taenia solium cysticercosis in humans was carried out in a rural area. Shandong province, China. Forty-eight cases with cysticercosis were ascertained through a prevalence survey conducted among 7281 persons in 1993. For each case, four controls residing in the same village and matched for age and sex were randomly selected. Information regarding demographic, social and behavioural factors was collected during house visits through interviews and direct observation. Risk factors strongly associated with human cysticercosis included poor personal hygiene, being unable to recognize cysticerci-containing meat, poor pig-raising practices and a history of passing tapeworm proglottides. The results indicate that health education in combination with chemotherapy for taeniasis is required for the control of cysticercosis in humans. PMID- 9363021 TI - Rotavirus, astrovirus and adenovirus associated with an outbreak of gastroenteritis in a South African child care centre. AB - An outbreak of gastroenteritis in the infant-toddler unit of a child care centre (CCC) in Pretoria, South Africa, was investigated for possible viral enteropathogens. Rotavirus was found in association with seven (70%) diarrhoeal episodes. Co-infection with rotavirus and human astrovirus (HAstV) was demonstrated in two of these episodes, and rotavirus, HAstV and enteric adenovirus (EAd) co-infection in another. Rotavirus occurred alone in four of the diarrhoeal episodes, while HAstV and EAd were each detected alone in one episode. Two HAstV and one rotavirus asymptomatic infection episodes also occurred. Overall, 8 of 10 children had rotavirus infections, of which 7 were symptomatic, 6 of 10 children had HAstV infections (4 symptomatic), and 2 of 10 children had EAd infection, both symptomatic. These results highlight the diversity of viral enteropathogens that may be associated with a diarrhoeal outbreak in a CCC and emphasize the need to investigate the possibility that multiple enteropathogens may simultaneously cause a single outbreak of diarrhoea. PMID- 9363023 TI - Prevalence of Salmonella in finishing swine raised in different production systems in North Carolina, USA. AB - We compared the prevalence of salmonella in faecal samples from finishing pigs and in feed samples from swine herds in North Carolina, USA. Farms were either finishing sites using all-in/all-out management of buildings in multiple-site systems (14 farms) or farrow-to-finish systems using continuous flow management of finishing barns (15 farms). The two groups of herds differed with respect to several management variables. Salmonella were isolated from 565 of 2288 (24.6%) faecal samples and from at least 1 faecal sample on 24 of 29 (83%) farms. Predominant serotypes were S. derby, S. typhimurium (including copenhagen), S. heidelberg, S. worthington and S. mbandaka. Fewer farrow-to-finish farms were detected as positive compared with all-in/all-out farms. Prevalence was lower for pigs raised on slotted floors compared with all other floor types, and was highest for pigs raised on dirt lots. Modern methods of raising pigs in multiple site production systems, using all-in/all-out management of finishing pigs, appear to have no benefit in reducing the prevalence of salmonella compared with conventional farrow-to-finish systems. PMID- 9363024 TI - A 1-year study of Escherichia coli O157 in cattle, sheep, pigs and poultry. AB - Samples of rectal faeces were collected immediately after slaughter from 400 cattle each month for a 1-year period and from 1000 each of sheep, pigs and poultry over the same period. Samples were examined for Escherichia coli O157 by enrichment culture in buffered peptone water with vancomycin, cefixime and cefsulodin followed by immunomagnetic separation and culture of magnetic particles onto cefixime tellurite sorbitol MacConkey agar. E. coli O157 was isolated from 752 (15.7%) of 4800 cattle, 22 (2.2%) of 1000 sheep and from 4 (0.4%) of 1000 pigs, but not from any of 1000 chickens. Of the cattle sampled. 1840 (38.4%) were prime beef animals, 1661 (34.6%) were dairy animals being culled and the status could not be determined for the other 1299 (27%) animals. E. coli O157 was found in 246 (13.4%) of the 1840 beef cattle and 268 (16.1%) of the 1661 dairy cattle. The monthly prevalence of E. coli O157 in cattle was 4.8 36.8% and was at its highest in spring and late summer. Seventeen of the 22 isolates from sheep were also made over the summer period. All E. coli O157 isolates from sheep and 749 (99.6%) of the 752 E. coli O157 isolates from cattle were verocytotoxigenic as determined by Vero cell assay and DNA hybridization, eaeA gene positive, contained a 92 kb plasmid and were thus typical of strains causing infections in man. In contrast isolates from pigs were non-toxigenic, eaeA gene negative and did not contain a 92 kb plasmid and would, therefore, be unlikely to be a source of infection for man. PMID- 9363025 TI - Persistence of Escherichia coli O157:H7 in dairy cattle and the dairy farm environment. AB - The persistence of Escherichia coli O157:H7 in cattle and the farm environment was investigated on eight Ontario dairy farms positive for E. coli O157:H7 in a longitudinal study commenced one year previously. Faecal samples from cows, calves, humans, cats, rodents, wild birds, a composite fly sample and numerous composite and individual environmental samples were cultured and tested for verotoxin-producing E. coli (VTEC). VTEC isolates were serotyped and E. coli O157:H7 isolates were phage typed. E. coli O157:H7 phage type 34 was isolated from one calf on each of two farms. The same phage type had been isolated on one of these farms 12 months earlier. Most E. coli O157:H7-positive animals and farms became culture-negative within 2 and 3 months, respectively. E. coli O157:H7 was not isolated from any environmental samples, although evidence of VTEC was found in composite samples from calf feeders (19.1%), calf barn surfaces (18%), cow feeders (14.9%), flies (12.5%), cow barn surfaces (11.3%), and individual milk filters (12.5%). VTEC belonging to 21 non-O157 serotypes were isolated from 24 cows (8.2%), 21 calves (18.3%), 2 cow feeder samples (3.0%), and 1 calf feeder sample (4.8%). Shedding of E. coli O157:H7 by infected dairy cattle appears to be transient and persistence of E. coli O157:H7 was not demonstrated from the farm environment sites tested. PMID- 9363026 TI - Fine-structure molecular epidemiological analysis of Staphylococcus aureus recovered from cows. AB - Sixty-three Staphylococcus aureus isolates recovered from bovine sources in the USA and the Republic of Ireland were characterized by multilocus enzyme electrophoresis (MLEE), ribotyping, and random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) typing at two separate laboratories. The S. aureus isolates were assigned by MLEE to 10 electrophoretic types (ETs) (Index of Discrimination, D = 0.779). In contrast, the same isolates were assigned to 13 ribotypes (D = 0.888), and to 12 RAPD types (D = 0.898). A common clone, ET3, of worldwide distribution, was represented by six distinct combinations of ribotypes and RAPD types. S. aureus clones recovered from cows in Ireland were also associated with mastitis in dairy cows in the USA. These findings are consistent with the hypothesis that only a few specialized clones of S. aureus are responsible for the majority of cases of bovine mastitis, and that these clones have a broad geographic distribution. PMID- 9363027 TI - Human hydatidosis in Dalmatia, Croatia. AB - Human echinococcosis remains a very serious public health problem worldwide, although a decline in incidence has been observed in some endemic areas during the last decades. However, in some non-endemic areas an increase in new cases and new foci of animal echinococcosis were registered during the same time. In Dalmatia, a well known endemic area of hydatidosis in the most Mediterranean part of Croatia, from the mid-1950s until present a decrease of incidence of over 70% has been registered. Age, sex and occupational category specific incidence as well as lethality rate have remained the same as before. Migrations from rural to urban regions seem to be the most important parameter in the changing epidemiology of human hydatidosis in Dalmatia. PMID- 9363028 TI - Changing prevalence of antibody to Dengue virus in paired sera in the two years following an epidemic in Taiwan. AB - To elucidate the epidemic pattern of a dengue outbreak in southern Taiwan during 1987-8, antibody prevalence rates were investigated in paired sera collected in both epidemic (Kaohsiung) and non-epidemic (Tainan) areas. In Kaohsiung, the IgG prevalence rate in 1989 was significantly higher (9.23%) than that in 1988 (5.29%) suggesting that new infections continuously appeared after the first bleeding in 1988. Although IgG antibody persisted in most infected blood samples, waning of antibody occurred in 6/355 (1.69%) of Kaohsiung sera. IgM antibody was only detected in Kaohsiung sera, suggesting that Tainan was not involved in the outbreak. Because IgG antibody was present in some samples collected in 1989, but not in 1988, from the non-epidemic area, sporadic infections perhaps occurred. Additionally, 4/355 (1.13%) of Kaohsiung sera showed IgM antibody positive in both 1988 and 1989. In turn, secondary infections may have occurred because of circulation of multiple-types of the virus. The possible relationship between low levels of dengue haemorrhagic fever (DHF) and the loss of IgG antibodies over time is also discussed. PMID- 9363029 TI - The declining HBsAg carriage rate in pregnant women in Hong Kong. AB - The HBsAg status and demographic data of 2480 pregnant women who attended antenatal clinics at Maternal and Child Health Centres in Hong Kong were collected by means of a self-administered questionnaire over a 1-week period in July 1996, to explore the underlying reason of a higher than expected HBsAg prevalence. Local women constituted 49.2% of the sample, mainland Chinese 39.7% and others 11.1%. The overall HBsAg prevalence was 10.0%. When related to place of birth, those born in Hong Kong had a prevalence of 8.4% whereas the prevalence of those born in mainland China was 13.1% (P < 0.001). The overall HBsAg carriage rate is high because of a higher rate in immigrants in the community. It is apparent that the HBsAg prevalence of local people in Hong Kong has been decreasing in the past decade. Overall, the current HBsAg carriage rate in the local adult population is estimated to have declined to about 8%. PMID- 9363030 TI - Risk factors for methicillin-resistant Staphylococcus aureus (MRSA) infection in a Japanese elderly care nursing home. PMID- 9363031 TI - The unstable medical research paper. PMID- 9363032 TI - Does admission to a medical department improve patient life expectancy? AB - Doubts about the effectiveness of medical care in improving patient health have been raised by epidemiological studies and by studies of geographical variation and inappropriate use of health care. To investigate this problem, the life expectancy gain (LEG) from consecutive admissions to a department of internal medicine during a six-week period was assessed by two expert panels, each consisting of an internist, a surgeon, and a general practitioner. The mean LEG for all admissions was 2.25 years (n = 422). Sixty-one percent had a LEG of 0.10 years or less, while 5% had a LEG of more than 9.98 years. In a probabilistic sensitivity analysis, the mean LEG remained greater than zero under assumptions of overestimated positive LEG and underestimated negative LEG. We conclude that the life expectancy of the majority of the patients was not influenced by the admission, but that a minority had substantial gains, resulting in a high overall mean LEG. PMID- 9363033 TI - Factors affecting the comparability of meta-analyses and largest trials results in perinatology. AB - The objective of this report is to provide a new methodology for evaluating the performance of meta-analysis (MA) in corroborating results of large trials (LT) and to identify factors that could explain lack of similarity in the results. We used two criteria to judge the degree of similarity between a MA and the LT: (a) the ratio of the relative risk of the MA to the relative risk of the LT; and (b) the 95% confidence interval about this ratio. Furthermore, this degree of similarity was cross-tabulated with the presence or not of evidence of selective inclusion of positive studies (e.g., publication bias) as judged from "funnel plots" and statistical indicators. Depending on which of our two criteria was used, we found that between 20% and 53% of the 30 MAs studied have high or very high degree of similarity with the LT. We also found strong evidence that factors influencing asymmetrical funnel plots of MA, such as publication bias, may play an important role in this degree of similarity. There was a sizeable proportion of meta-analyses that did not agree with large trial results. We recommend that funnel plots be used as a tool for identifying which MAs can mislead. However, the statistical indicators at hand are unlikely to be of use in many area of medicine considering the regrettably small number of randomized controlled trials per topic available. PMID- 9363034 TI - Cardiovascular risk factors prior to the development of non-insulin-dependent diabetes mellitus in persons with impaired glucose tolerance: the Hoorn Study. AB - The aim of the study was to analyze cardiovascular risk factors as predictors for developing non-insulin-dependent diabetes mellitus (NIDDM) in people with impaired glucose tolerance. A cross-sectional survey of glucose tolerance was conducted in people, aged 50-74, who were randomly selected from the registry of the middle-sized town Hoorn (The Netherlands). Based on the mean values of two oral glucose tolerance tests, people were classified in glucose tolerance categories according to the WHO criteria. The mean follow-up time was 36 months (range 13-55 months). The cumulative incidence of NIDDM was 34% (95% CI 16.9 45.1). In multiple logistic regression analysis, cardiovascular risk factors at baseline did not predict the conversion from impaired glucose tolerance to NIDDM, in contrast with the two-hour plasma glucose level (odds ratio 3.56, p < 0.001) and the fasting proinsulin level, as one of the determinants of beta-cell dysfunction (Odds ratio 2.1, p < 0.05). The baseline HDL-cholesterol level, one of the components of the insulin resistance syndrome, was associated with the conversion from impaired glucose tolerance to normal glucose tolerance (Odds ratio 1.58, p < 0.05). The results of our study seem to support the hypothesis that conversion from impaired glucose tolerance to normal glucose tolerance depends on insulin resistance and the development of NIDDM from impaired glucose tolerance depends on beta-cell dysfunction. PMID- 9363035 TI - Reliability of a comorbidity measure: the Index of Co-Existent Disease (ICED). AB - The reliability of an established comorbidity index (the Index of Co-Existent Disease) was tested using retrospective data from the case notes of elderly patients who had undergone total hip replacement. Inter-rater reliability was examined twice, first with two raters (n = 39) and then with three (n = 49). Intra-rater reliability was assessed using one rater (n = 45). Reasons for any lack of reliability were explored. The inter-rater reliability of the ICED was moderate (kappa 0.5-0.6). While the Functional Severity index performed well (kappa 0.6-1.0), the Index of Disease Severity subindex was less reliable (kappa 0.4-0.5). Differences between raters had an impact on the observed association between comorbidity and serious post-operative complications. Intra-rater reliability was excellent (kappa 0.9). Several reasons why inter-rater reliability was only moderate were identified, mostly related to uncertainties in applying the ICED. The reliability of the ICED needs to be improved before it is used more widely with retrospective data. This might be achieved by further clarification of the instructions for its use. PMID- 9363036 TI - Validation of a cerebral palsy register. AB - OBJECTIVES: To analyse completeness and validity of data in the Cerebral Palsy Register in Denmark, 1979-1982. METHODS: Completeness has been assessed by comparing data from The Danish National Patient Register (DNPR) with the cases included in the Cerebral Palsy Register (CPR). Agreement between 12 variables in the CPR and obstetrical medical records has been analysed using kappa-statistics. RESULTS: Of 468 children in the DNPR, only 237 fulfilled the inclusion criteria of the CPR; and 35 (15%) of these cases had not been reported to the CPR. Data agreement was generally good, but gestational age was subject to a systematic error, and urinary infections in pregnancy (kappa = 0.43) and placental abruption (kappa = 0.52) were seriously under-reported in the CPR. CONCLUSIONS: Completeness of the Cerebral Palsy Register in Denmark, 1979-1982, has been assessed to maximal 85%, emphasizing the impact of using supplementary case ascertainment sources in the future. Validity of data varied according to definition and significance of the specific variable. PMID- 9363037 TI - Low education is a genuine risk factor for accelerated memory decline and dementia. AB - A relatively high prevalence and incidence of dementia have been found in population strata with low levels of education in comparison to population strata with high levels of education. However, doubt remains whether this may be an artifact of education bias in the screening tests used. To investigate this matter, we analyzed results of two Dutch population surveys in which unbiased measures of memory decline were used. In the Longitudinal Aging Study Amsterdam (n = 1774) the percentage of words retained in a verbal learning test was found to be disproportionately low in the oldest age cohort (80-85 years) with less than 11 years of education. The Amsterdam Study of the Elderly (n = 4051) found a "dose-response" relationship between education and dementia prevalence. Cross sectional and longitudinal results showed that, in less educated people, memory decline is faster and sets in at an earlier age. These findings indicate that the relationship between dementia and education is not just an artifact of case detection methods. PMID- 9363039 TI - Serum LP(a) levels in African aboriginal Pygmies and Bantus, compared with Caucasian and Asian population samples. AB - Serum lipoprotein(a) (Lp(a)) and its correlates were studied in African Aboriginal Pygmies (n = 146) and Bantus (n = 208) from Cameroon. Geometric mean Lp(a) levels were 274 and 289 mg/l in Bantu males and females, respectively, and 220 and 299 mg/l in Pygmy males and females, the gender difference being significant in Pygmies (p = 0.024). In Pygmies 41% and 52% of the males and females, respectively, had Lp(a) levels above 300 mg/l, compared with 47% and 55% in Bantus. Overall, Lp(a) levels did not significantly differ between Pygmies and Bantus, and did not correlate with age, body mass index (BMI), systolic and diastolic blood pressure. Compared with healthy Asian and Caucasian population samples, age- and BMI-adjusted geometric Lp(a) means were 2.3- to 5.0-fold higher in Pygmy and Bantu males, and 2.9- to 3.6-fold higher in Pygmy and Bantu females (p < or = 0.05). Across the population samples studied ethnicity predicted 12% and 17% of serum Lp(a) variance in males and females, respectively. PMID- 9363040 TI - The International Continence Society (ICS) incontinence definition: is the social and hygienic aspect appropriate for etiologic research? AB - OBJECTIVE: To investigate the effect of applying a problem assessment versus a pure symptom urinary incontinence (UI) caseness definition in etiologic research. SUBJECTS: A random population sample of 2613 women aged 30-59 years, who responded to a postal questionnaire. MAIN PARAMETERS: One-year period prevalence of the symptom of stress UI; UI assessed by the woman to be a social and/or hygienic problem; childbirth and history of abdominal, gynecological, obstetric or urologic surgery. RESULTS: Among the 388 women (14.8% of the population sample) who reported stress UI, 62.6% considered it a social or hygienic problem, and 21.9% had ever abstained socially because of UI. Applying a problem assessment caseness definition caused under-estimation of the role of childbirth, as compared with analyses including a pure symptom caseness definition. CONCLUSION: The International Continence Society (ICS) incontinence definition presents intrinsic logical problems that invalidates its use in biomedical, if not in sociomedical, research. As definition and medical decision are different concepts, this does not necessarily affect the potential utility of the problem assessment aspect when used in everyday clinical practice as a basis for the decision whether to treat women with UI or not. PMID- 9363038 TI - Differences in quality of life among patients receiving dialysis replacement therapy at seven medical centers. AB - The purpose of this study is to investigate the variations in quality of life (QOL) among patients with end-stage renal disease (ESRD) who are receiving replacement therapy in several dialysis centers. This observational study includes interviews with nurses and data extraction from medical charts for all 680 adults who had been on dialysis therapy for more than 4 weeks in seven dialysis centers. By using multivariate analysis, we generated a model to explain the variance in QOL as measured by the QL index score (developed by Spitzer et al., J Chronic Dis 1981; 34:585-597) among patients pooled from all centers. The expected mean QL index score and 95% confidence interval were computed for each dialysis center. Centers with observed mean QL index scores outside of the expected confidence range were marked as possible outliers. We found the following patient attributes to be independently associated with QOL: age, education, occupation, and certain comorbidities (e.g., diabetes, stroke). After adjustment for case mix, we could identify four outlier centers. After further adjustment for albumin in serum, a possible process indicator, two centers were no longer considered as outliers. These findings indicate that the variance in QOL of ESRD patients at different centers is not entirely explained by known case mix factors. Further research should explore whether such variations are related to dissimilarity in the process of care at different centers. PMID- 9363042 TI - The clinical presentation of generalized anxiety in primary-care settings: practical concepts of classification and management. AB - On the basis of our long-term experience in treating family-practice patients and conducting clinical research with them, we propose a practical clinical nosology that takes into account the subsyndromal spectrum of generalized anxiety, as well as patterns of illness, particularly for the family-practice setting. We present an alternative proposal of how to conceptualize generalized anxiety disorders clinically into acute anxiety, subacute anxiety, chronic anxiety, and double anxiety. This is followed by a discussion of the implications for choosing from among the various anxiolytic treatment options available to the family physician and of the importance of the therapeutic context in which treatment is provided. Anxiolytics are not a panacea, but only tools to allow the patient to help himself or herself. Irrespective of which anxiolytic is chosen, and irrespective of the chronicity of the anxiety, short-term (2 to 6 weeks) anxiolytic therapy- if necessary provided more than once on an intermittent basis--should be the treatment approach of first choice. Data are presented to suggest that 50% of all chronically ill patients who have generalized anxiety disorder could benefit from such a treatment approach. PMID- 9363041 TI - Dispensing epilepsy medication: a method of determining the frequency of symptomatic individuals with seizures. AB - We estimated the prevalence and incidence of epilepsy in The Netherlands using drug-dispensing information from the PHARMO database, containing medication histories of nearly 300,000 individuals. An algorithm based on antiepileptic drug prescription records was used to identify patients with epilepsy requiring medication for seizure control. The algorithm was validated by comparing positive algorithm identifications to medical diagnoses from general practitioners and hospital records. In 1990-1991, the algorithm revealed 1158 patients with "certain" epilepsy, and 451 patients with "probable" epilepsy. Epilepsy was present in 93% of patients on polytherapy, and 58% on monotherapy. Clonazepam monotherapy was non-specific for epilepsy. The use of carbamazepine monotherapy for epilepsy was age-dependent. After correcting the algorithm for these drugs, and standardizing to the Dutch population, the point prevalence of epilepsy was 4.8/1000 (95% CI: 4.5-5.0). The incidence rate was 0.72/1000 person-years (95% CI: 0.65-0.79). Using drug-dispensing data for epilepsy medication, it is possible to make valid estimations of the number of epilepsy patients requiring drug therapy. PMID- 9363043 TI - A double-blind evaluation of the safety and efficacy of abecarnil, alprazolam, and placebo in outpatients with generalized anxiety disorder. Abecarnil Work Group. AB - In a placebo-controlled, multicenter study, 180 male and female outpatients, ages 18-65, with DSM-III-R generalized anxiety disorder, were treated with abecarnil (a partial benzodiazepine agonist), alprazolam, or placebo for 4 weeks. This was followed by a rapid (1-week) taper, during which patients were assessed for any taper-related symptoms. All patients were identified via a structured clinical interview for DSM-III-R and randomly assigned to one of the three treatment groups. More than 70% of each treatment group completed the study. In the acute treatment phase, both abecarnil and alprazolam showed evidence for efficacy that was significantly better than that of placebo. Both active agents were tolerated well. After the swift taper, a significantly greater number of taper-related symptoms occurred in the alprazolam-treated group than in the abecarnil-treated group, which was not different than in the placebo-treated group. Additionally, less residual improvement followed the taper in the alprazolam-treated and the placebo-treated groups. These data indicate that the partial benzodiazepine agonist abecarnil may be useful as a safe, effective, short-term treatment for anxiety. Theoretical and practical implications of these findings are discussed. PMID- 9363044 TI - Abecarnil for the treatment of generalized anxiety disorder: a placebo-controlled comparison of two dosage ranges of abecarnil and buspirone. AB - BACKGROUND: The development of effective and well-tolerated anxiolytic agents is an area of critical clinical importance. Abecarnil, a beta carboline, is a partial benzodiazepine-receptor agonist that has demonstrated promise as an anxiolytic agent. In this study, we examine the efficacy, safety, and discontinuation-related effects of abecarnil, buspirone, and placebo in the acute and long-term treatment of patients who have generalized anxiety disorder. METHOD: This is a double-blind, placebo-controlled study of two dosages of abecarnil and buspirone. In total, 464 patients were randomized. After a placebo run-in week, patients entered a 6-week double-blind treatment period, followed by an optional 18-week maintenance period for treatment responders. After abrupt discontinuation of the acute or maintenance treatment, patients entered a 3-week placebo-substitution follow-up period. Treatment response was assessed with the Hamilton Rating Scale for Anxiety and the Clinical Global Impressions (CGI) Scale. RESULTS: Compared with placebo, abecarnil showed significant anxiolytic activity early in the treatment period, particularly in the high-dosage group, though these differences did not maintain statistical significance at the end of the trial. Buspirone was associated with a slower onset of action and better symptom relief than placebo after 6 weeks of therapy. Withdrawal symptoms emerged in patients who abruptly discontinued abecarnil (particularly at the higher dosage) only in those receiving a longer duration of treatment. CONCLUSION: The results of this study need to be understood in the context of a high placebo response rate, which hampers the ability to demonstrate significant drug-placebo differences. This study suggests that abecarnil may be an effective anxiolytic agent; further attention is warranted to assess its spectrum of clinical effectiveness. PMID- 9363046 TI - Placebo response in generalized anxiety: its effect on the outcome of clinical trials. AB - The development of new treatments for generalized anxiety disorder increasingly has been sabotaged by a high placebo-response rate. As a consequence, and in contrast to the surge of approvals for new antidepressants, only one new anxiolytic has been approved by the U.S. Food and Drug Administration in the past 15 years. This article presents a brief review of factors that contribute to the placebo response in treatment studies of generalized anxiety. Since anxiety is a normal emotion that is sensitive to a variety of life stresses, it is particularly difficult to achieve the primary goal of a clinical trial, which is to extract the "signal" of a drug effect from the "noise" of background fluctuations in symptoms. Data from the published literature and from the authors' research unit concerning placebo-response trends are reviewed. PMID- 9363045 TI - Double-blind, placebo-controlled trial of two doses of abecarnil for geriatric anxiety. AB - We studied the tolerability and efficacy of abecarnil, a new partial benzodiazepine agonist, for short-term relief of anxiety in geriatric patients. After a 1-week placebo lead-in, 182 outpatients (mean +/- SD age = 68.3 +/- 5.8; range, 59-85 years) were randomly assigned in a double-blind, parallel-group design to high-dosage abecarnil (7.5-17.5 mg daily), low-dosage abecarnil (3.0 7.0 mg daily), or placebo for 6 weeks of acute treatment followed by abrupt discontinuation and a 2-week follow-up. During the acute treatment period, the discontinuation rate from adverse events was greater for the group treated with high-dosage abecarnil (44%) than for the groups treated with low-dosage abecarnil (14%) or placebo (12%). The most frequently reported side effects associated with abecarnil were drowsiness and insomnia. For the acute treatment period, low dosage abecarnil was superior to placebo in reducing anxiety at Weeks 2-4 and 6, and was statistically significantly superior to high-dosage abecarnil at Weeks 4 6. More than half of the placebo group showed at least moderate global improvement at Weeks 3 and 6. One week after abrupt discontinuation of abecarnil, the placebo-treated group had less anxiety than did both groups treated with high dosage and low-dosage abecarnil. The most commonly reported symptoms of withdrawal were headache and insomnia. These data indicate that abecarnil, at dosages ranging from 3.0 to 7.0 mg daily, is better tolerated and more efficacious for the short-term treatment of anxiety in geriatric patients than are higher dosages of 7.5 to 17.5 mg daily. Abrupt discontinuation of abecarnil at either dosage range causes definite rebound symptoms within the first week after withdrawal. These data also suggest that treatment with placebo offers at least moderate relief of anxiety in many elderly patients. PMID- 9363047 TI - Respiratory infections in the 1990s. AB - Respiratory infections occur in a variety of settings, affecting patients who live in the community, those who are hospitalized, as well as residents of chronic care facilities. Management of pneumonia and bronchitis is continually changing as the nature of the infecting pathogens, the susceptibility of microbes to antibiotics, and the nature of the host at risk for infection are evolving. Advances in the understanding of disease pathogenesis have led to new approaches for therapy and prevention, using a variety of techniques ranging from immunization to the manipulation of cytokines. One inevitable consequence of this ever-changing field is that our incomplete foundation of knowledge leads to disagreements among experts about the most efficient approach to disease management. In this review, a number of these controversies are examined, with a particular emphasis on the diagnostic approach to pneumonia arising in both the community and the hospital. In addition, a number of pathogenetic and epidemiologic principles are examined, which may have bearing on the prevention of pneumonia in the elderly and the mechanically ventilated patient. PMID- 9363048 TI - Pathogenesis and host defense in pulmonary infections. AB - The development of pneumonia typically results from an overwhelming bacterial inoculum or a breakdown in the integrity of the host's pulmonary defense mechanisms. Augmentation of pulmonary defenses is one means of reducing the incidence, morbidity, and mortality from pneumonia. Strategies to enhance pulmonary or systemic defenses are actively being investigated. Selected established and investigational measures enhancing host defense mechanisms against various pathogens are reviewed. PMID- 9363049 TI - Unusual pathogens for respiratory infections. AB - There are a large number of unusual pathogens for respiratory tract infections. The list of such pathogens is continuously changing because of changes in our environment, changes in the host (especially immunosuppression), and advances in medical technology, which allow minimally or otherwise nonpathogenic microorganisms to cause respiratory tract infections. Changes may also occur in common microorganisms such as penicillin-resistant pneumococci or multidrug resistant Mycobacterium tuberculosis. Finally, usual pathogens may result in unusual manifestations. PMID- 9363050 TI - Bronchitis. AB - Acute bronchitis in previously fit individuals is a common condition that is usually mild and self limiting. Chronic bronchitis remains a common cause of morbidity and mortality, and the cost to the nation due to lost working days and to health services is enormous. Cigarette smoking is the major etiologic factor, although exacerbations may be caused by viruses, environmental pollutants, allergic responses, and bacterial infections. New insights into the underlying basic mechanisms of bronchial inflammation are being made. Antibiotics are commonly used to treat exacerbations, although evidence of efficacy is sometimes lacking. Some patients may be prone to recurrent exacerbations and this influences their chance of recovery. Clinical trials must include an assessment of the severity of the exacerbation, and protocols would be improved by increased definition of the type of patient being enrolled and by inclusion of more detailed measures of benefit. Influenza and pneumococcal vaccination should be encouraged in appropriate patients. PMID- 9363051 TI - Community-acquired pneumonia. AB - In the past year, community-acquired pneumonia has continued to represent an important area of interest in the literature. Some reports improved our knowledge of epidemiology and outcome. New developments in the technology of molecular biology may soon be incorporated into the laboratory routine to obtain an earlier diagnosis of certain etiologies in individuals with severe episodes. However, the majority of reports on community-acquired pneumonia focus on treatment. New approaches to improve management are directed to reduce costs while maintaining equivalent clinical efficacy. Despite these advances, many areas need further research in the future. PMID- 9363052 TI - Nosocomial pneumonia in the noncritical care setting. AB - The optimal approach to the recognition, management, and prevention of nosocomial pneumonia is evolving. A broad spectrum of potential pathogens is recognized in the hospital setting, and more invasive procedures have been developed in attempts to improve diagnostic accuracy. Newer, broad spectrum antimicrobial agents are continually introduced, yet the presence of resistant organisms is increasingly recognized. The reports released in the past year show physicians are making advances toward gaining a better understanding of this common infection. PMID- 9363053 TI - Nosocomial pneumonia. AB - Despite many advances in infection control measures, nosocomial pneumonia remains a frequent complication in ventilator-dependent patients cared for in the intensive care unit. During the past year in review, many important articles have been published dealing with critical issues for the optimal management of such patients. Nasal cannulation for endotracheal and gastric intubation has been recognized as a major risk factor for nosocomial infection in patients requiring mechanical ventilation. Although selective digestive decontamination remains highly controversial due to the risk of selecting for multi-resistant microorganisms, the potential benefit of using sucralfate for prevention of late onset pneumonia appears promising. There has been relatively little progress made regarding the optimal management strategy to use in patients with suspected pneumonia, except that protected specimen brush and bronchoalveolar lavage techniques were both qualitatively and quantitatively demonstrated to reliably identify microorganisms present in the lung, even when the infection develops as a superinfection in a patient already receiving antimicrobial therapy. Antibiotic treatment of nosocomial pneumonia remains a complex undertaking, and further trials will be ultimately needed to clarify in which circumstances monotherapy can be safely used. PMID- 9363054 TI - Pulmonary infections in immunosuppressed patients. AB - Pulmonary infections continue to be a significant problem in patients immunosuppressed by cancer or by drugs given for malignancy, or rheumatologic or dermatologic problems. For the neutropenic patient, single-drug rather than combination antibiotic therapy is being increasingly used. The role of growth factors is also being defined. The availability of the new azoles and of alternative forms of amphotericin B have increased treatment options, particularly for invasive pulmonary aspergillosis. Pneumocystis carinii pneumonia continues to be a problem in this population, and controversy remains about the mode of transmission and the mechanism of disease caused by this infection. Exogenous infection rather than reactivation may play a small role. Appreciation of the role of community and opportunistic viruses in causing respiratory infection or other complications in the immunosuppressed population is also being further detailed. PMID- 9363056 TI - Respiratory infections in patients with HIV. AB - Pneumocystis carinii pneumonia has long been considered the predominant pulmonary disease in patients with HIV, but several factors are changing this perception. The population infected with HIV is increasingly composed of injection drug users, and racial and ethnic minorities, which represent groups that have a high incidence of bacterial pneumonia and tuberculosis. The increased longevity attributed to antiretroviral therapy and P. carinii pneumonia prophylaxis is accompanied by more profound immunosuppression, rendering patients susceptible to Pseudomonas, Aspergillus, and other opportunistic pneumonias. Trimetrexate and atovaquone are now available for the treatment of P. carinii pneumonia. Both are less effective than standard regimens of trimethoprim-sulfamethoxazole, but have fewer adverse effects. The diagnosis of respiratory infections complicating HIV usually depends on isolation of the pathogen. The routine use of transbronchial biopsy during bronchoscopy is controversial because the prevalence of P. carinii pneumonia is high in most centers caring for patients with AIDS, and bronchoalveolar lavage is usually diagnostic in this disease. However, biopsy enhances the yield of bronchoscopy, especially in the diagnosis of noninfectious pulmonary disorders and infections other than P. carinii pneumonia. PMID- 9363055 TI - Respiratory infections following organ transplantation. AB - Successful organ transplantation often is limited by infection. The early transplant period is predominated by bacterial and fungal infections related to surgery and neutropenia, whereas opportunistic infections occur later due to long term immunosuppression therapy. Despite technical differences between various types of organ transplants, the diagnostic approaches to lung disease are similar and rely largely on fiberoptic bronchoscopy. Whereas better antibacterial prophylaxis is available, fungal infections are emerging as significant problems. Lipid suspension formulations of amphotericin B and itraconazole offer new treatment options for fungal pulmonary infection. These formulations appear to have improved pharmacologic safety, but relative efficacy is unclear. Cytomegalovirus infections continue to plague transplant recipients. Improved understanding of the risk factors (especially the role of screened blood products) and improved prophylactic strategies with ganciclovir and immunoglobulin are decreasing the incidence of fatal infection. Surveillance for viremia and antigenemia now permit early identification of patients at significant risk for clinical disease, and responses to prompt administration of ganciclovir are encouraging, especially among solid organ recipients. PMID- 9363057 TI - The noninfectious respiratory complications of infection with HIV. AB - Infection with HIV was first recognized through a clustering of unusual respiratory infections. The lung has been a major target manifesting many of the infectious complications of the immunodeficiency. Noninfectious pulmonary complications in HIV-infected individuals are also common and have been recognized since the advent of the AIDS epidemic. Malignancies involving the respiratory system, specifically Kaposi's sarcoma and non-Hodgkin's lymphoma, are epidemiologically linked to infection with HIV. Although other cancers have been identified in patients with HIV, these malignancies have a relationship to HIV infection that is unknown. Nonetheless, all cancers in the HIV-infected individual appear to follow a very deadly course. Interstitial pneumonitis and an alveolitis are also seen in individuals infected with HIV. Their relationship to the virus is unknown but may involve the lung's immune response to HIV. Pneumothorax and bullous lung disease are the sequela of pulmonary infections in the HIV-infected host. Pulmonary hypertension has been reported in HIV-infected patients, and like the other noninfectious respiratory complications, the link between the disease process and HIV is unknown. Bronchiectasis is now commonly recognized in AIDS patients who have survived prolonged immunosuppression and infection. Bronchoscopists have accumulated a collection of endobronchial lesions uncommonly seen in non-HIV-related pulmonary consultation. In the following review, we discuss the epidemiology, pathology, pathogenesis, clinical features, diagnostic findings, prognosis, and therapeutic options available for each noninfectious pulmonary complication. As the life expectancy for HIV-infected patients increases, the incidence of noninfectious pulmonary complications will rise. PMID- 9363058 TI - Tuberculosis: a survey and review of current literature. AB - Despite being a treatable and preventable disease, tuberculosis will kill an estimated 30 million people during the current decade. Tuberculosis is a global problem, and increases in case rates are occurring not only in the developing countries of the world but also in several industrialized nations, such as the United States. Coincident with the resurgence of tuberculosis in the United States, there has also been an alarming increase in the number and proportion of cases caused by strains of Mycobacterium tuberculosis that are resistant to multiple first-line drugs. The increase in multiple-drug resistant tuberculosis has re-taught physicians about the importance of pursuing and ensuring treatment until cure. The HIV epidemic is playing a pivotal and permissive role in the resurgence of tuberculosis morbidity and mortality in those populations where tuberculosis and HIV are prevalent and overlap. Co-infection with HIV distorts the natural history and clinical expression of tuberculosis. Molecular biology has yielded important insights into the mechanisms of drug resistance and provided powerful tools for the rapid diagnosis and epidemiologic study of this disease. PMID- 9363059 TI - Infectious diseases. PMID- 9363060 TI - Dilemmas and controversies surrounding bronchogenic carcinoma. PMID- 9363061 TI - Tests for diagnosis and staging of bronchogenic carcinoma. AB - Bronchogenic carcinoma continues to be a significant cause of both morbidity and mortality. Despite the attempts to reduce exposure to known causative agents, such as tobacco, the incidence of lung cancer continues to rise. New methods are being developed to aid in the early detection and localization of lung cancer in hopes that overall survival can be improved. More accurate staging may prevent patients who have advanced disease from encountering the morbidity associated with thoracotomy. This review summarizes some of the new methods being evaluated to assist in the early diagnosis and staging of bronchogenic carcinoma. PMID- 9363062 TI - Treatment of bronchogenic carcinoma. AB - Progress in the treatment of bronchogenic carcinoma, the leading cause of cancer death in men and women in the United States, has been slow throughout the past few years, and no major breakthroughs have occurred in the past 12 months. Significant developments in monoclonal antibody techniques and tissue cellular markers offer hope for improved diagnosis and are useful in staging and following disease response to treatment. Advances in patient selection and staging have been primarily responsible for improved surgical outcomes, but some new surgical alternatives like video-assisted thoracoscopy and other tissue-sparing procedures may offer reasonable outcomes with a lower morbidity. New drugs and new drug combinations are being evaluated with hematopoietic growth factors in the management of small cell lung cancer. Neoadjuvant chemotherapy and radiotherapy are finding a definite role in the management of non-small cell lung cancer. The optimal parameters for radiotherapy in the management of small cell lung cancer are being defined. The use of immunotoxins, adjuvant immunotherapy, and monoclonal antibodies offers major theoretical promise, but are as yet in the early stages of development. Ancillary techniques for palliation of local airway obstruction, including both laser and endobronchial stents, are proving beneficial in selected patients. PMID- 9363063 TI - Intrathoracic neoplasms other than bronchogenic carcinoma. AB - Intrathoracic neoplasms other than lung cancer represent a diverse group of diseases. This review focuses on the recent literature addressing mediastinal neoplasms, unusual primary lung neoplasms, and pulmonary metastases from other locations. Advances in classification, imaging, diagnosis, surgical issues, and treatment issues shown in case series and individual case reports are presented and discussed. PMID- 9363064 TI - The biology of lung cancer. AB - Lung cancer remains the major cancer killer worldwide. Although advances have been achieved in the past 20 years in understanding the important clinical and prognostic factors for both small cell lung cancer and non-small cell lung cancer, with few exceptions no significant advances have been made in therapeutic results. For patients who have small cell lung cancer, the hope for prolonged survival relates to the sensitivity of the tumor to chemotherapy, with or without radiation therapy. For patients who have non-small cell lung cancer, the only hope for survival is whether the tumor can be surgically excised. Despite only modest advances and responses to systemic treatment for lung cancer, there have been major advances in our understanding of the biologic properties of lung cancer throughout the past decade and a half. The development of numerous cell lines of both major cell subtypes of lung cancer has allowed an in-depth study of its biologic and molecular properties. This paper reviews recent developments in the biology of lung cancer and how these advances may impact on the treatment of patients who have this disease. PMID- 9363065 TI - Pulmonary vascular disease. PMID- 9363066 TI - Objective tests for the diagnosis of deep leg vein thrombosis. AB - The concept that deep vein thrombosis and pulmonary embolism are one clinical entity has only recently established itself. Hence, the term venous thromboembolism should be used. The diagnosis of pulmonary embolism has been notoriously difficult, and pulmonary angiography via the reference method has played a prominent role. More recently, the use of less invasive or noninvasive diagnostic tools for patients who have inconclusive lung scan reports has been advocated. This option is based on observations that deep vein thrombosis is present in a substantial number of patients who have proven pulmonary emboli. The authors have reviewed the literature for available data on the use of objective tests for deep vein thrombosis in the management of patients who have clinically suspected pulmonary embolism. Although several clinical studies have shown promising results, no diagnostic strategy has been sufficiently evaluated to warrant the use of such tests for routine clinical practice. PMID- 9363067 TI - Anticoagulants and thrombolysis in the treatment of pulmonary embolism. AB - Intravenous heparin followed by oral warfarin sodium is effective for preventing recurrent thromboembolism in patients who have pulmonary embolism or proximal vein thrombosis. The effectiveness of intravenous heparin depends on obtaining an adequate anticoagulant response early during therapy. A validated heparin protocol should be used to ensure that an adequate anticoagulant response is obtained as soon as possible. Low molecular weight heparin has the practical advantage that it does not require monitoring and dose finding. If thrombolytic therapy is indicated, it is safer for many patients to base management on the noninvasive diagnosis rather than performing pulmonary angiography. In patients suspected to have pulmonary embolism who have nondiagnostic lung scan and adequate cardiorespiratory reserve, serial noninvasive leg testing is a practical approach that avoids pulmonary angiography, identifies patients who have proximal vein thrombosis requiring treatment, and avoids the risks of anticoagulant treatment in the majority of patients. PMID- 9363068 TI - Embolectomy, catheter extraction, or disruption of pulmonary emboli: editorial review. AB - Hippocrates said, "For extreme illness, extreme measures are warranted." Massive pulmonary embolism is an uncommon clinical problem for which extreme measures, such as surgical embolectomy, appear warranted. Since the application of cardiopulmonary bypass to surgical embolectomy in 1961, a number of uncontrolled retrospective case series suggest that nearly one half of patients survive when they undergo emergent embolectomy, in spite of preoperative cardiac arrest. Transvenous catheter embolectomy or catheter disruption of thrombi offers alternatives for hypotensive patients who do not require cardiopulmonary resuscitation. In addition, pulmonary artery stent placement can improve pulmonary artery flow for selected patients who have massive pulmonary embolism. PMID- 9363069 TI - Pulmonary hypertension and cor pulmonale. AB - An ever-expanding body of information has provided new insights into the pathophysiologic mechanisms contributing to pulmonary hypertensive disease. The pulmonary endothelial cell has been shown to have a central role in both the maintenance of normal vascular tone and in the pathogenesis of small vessel changes. The relationship between endothelium-derived mediators such as nitric oxide, prostacyclin, and endothelin-1 is likely to be important in the development of abnormal vasomotor tone and structure in the pulmonary vascular bed. Stimulated by this evolving understanding of pulmonary vascular physiology, recent literature abounds with references to novel therapeutic strategies in the care of patients who have both primary and secondary forms of pulmonary hypertension. Advances in surgical technologies have also expanded the therapeutic options for selected groups of pulmonary hypertensive patients. This article highlights recent developments in the understanding of pulmonary vascular pathophysiology and examines strategies for evaluation and treatment of pulmonary hypertension and cor pulmonale. PMID- 9363070 TI - Diseases of the pleura. AB - In this review, three aspects of pleural disease are discussed. Although it was thought for many years that the origin of pleural fluid was the capillaries in the parietal or visceral pleura, recent evidence suggests that in many cases the origin of pleural fluid is the interstitial space of the lung. The interstitial space of the lung appears to be the source of the pleural fluid in patients who have congestive heart failure, parapneumonic effusions, pulmonary embolism, and lung transplants. The Hantavirus pulmonary syndrome is characterized by rapidly progressive, noncardiogenic pulmonary edema in relatively young, previously healthy individuals. The mortality rate with this syndrome is approximately 60%, and at autopsy most patients have large pleural effusions. Patients after lung transplantation frequently have profuse drainage from their chest tubes because most of the fluid that enters the lung must exit through the pleural space. The incidence of pleural effusion is very high in patients who have a complication of their lung transplantation, but the pleural fluid findings in patients after lung transplantation have not been well studied. Similarly, virtually all patients who undergo liver transplantation have a right-sided pleural effusion. The effusion usually reaches its maximum size around the third postoperative day. If the effusion increases in size after this time, serious complications should be suspected. The approach to pleural diseases has been altered with the advent of videothoracoscopy. Videothoracoscopy should be considered in patients who have undiagnosed pleural effusions and are not improving; in patients who have had recurrent pneumothorax, or a spontaneous pneumothorax with a persistent airleak or unexpanded lung; or in patients who have a traumatic hemothorax with clotted blood. PMID- 9363071 TI - Pleuritis and pleural effusions. AB - A variety of diseases either directly or indirectly affect the pleura, resulting in the accumulation of pleural fluid. A pleural effusion develops whenever the influx of fluid into the pleural space is greater than the efflux. It is now clear that the parietal pleura has the primary role in the reabsorption of pleural fluid normally and during pathologic conditions. Recently, models of experimental pleuritis have demonstrated the importance of inflammatory cytokines in the pathogenesis of both asbestos- and endotoxin-induced pleural effusions. PMID- 9363072 TI - Pleural diagnostic techniques. AB - An etiologic diagnosis of a pleural effusion is made presumptively in approximately 50% of patients and definitively in an additional 25%. The cause of the effusion in the remaining patients usually is ascertained by observation with or without repeat pleural fluid analysis, specialized testing of the pleural fluid, or invasive procedures. However, a small number of patients defy a precise etiologic diagnosis even after invasive procedure. Investigators have sought various biochemical and immunologic markers in pleural fluid that would increase diagnostic certainty. Thoracoscopy, a less invasive procedure than open thoracotomy, is excellent for the diagnosis of malignancy but is of minimal benefit in the diagnosis of benign pleural disease. PMID- 9363073 TI - The etiology and treatment of spontaneous pneumothorax. AB - In the past year, studies on spontaneous pneumothorax have focused on etiology and treatment. Chronic obstructive pulmonary disease remains the most common cause of secondary spontaneous pneumothorax. However, Pneumocystis carinii infections in patients who have AIDS have become the leading cause of spontaneous pneumothorax in a population where its prevalence is high. One of the treatment modalities of spontaneous pneumothorax is tube thoracostomy with the instillation of tetracycline as the sclerosing agent. Tetracycline is no longer available. Fortunately, its derivatives doxycycline and minocycline are equally effective. Talc in slurry or insufflated appears to be more effective than tetracycline derivatives. Experience with talc in slurry for the treatment of spontaneous pneumothorax is still limited. Another treatment modality for spontaneous pneumothorax is thoracoscopy, more recently termed video-assisted thoracic surgery, and it has warranted renewed interest due to the advent of improved endoscopic technology. In the treatment of spontaneous pneumothorax, video assisted thoracic surgery is nearly as effective as thoracotomy. PMID- 9363075 TI - Neoplasms of the lungs. PMID- 9363074 TI - Pleural malignancies including mesothelioma. AB - Malignant mesothelioma is caused almost exclusively by occupational exposure to asbestos. During the past few years, however, increasing evidence has mounted that background exposure to asbestos could be sufficient to cause mesothelioma. Treatment of malignant mesothelioma remains a big problem. Some new approaches are on their way, and the most exciting ones are local immunotherapy in very early cases. Some success has been reported with local interferon treatment. As for treatment of metastatic pleural disease, the main purpose is symptomatic relief of dyspnea caused by fluid accumulation. The best way to achieve a lasting palliation is pleurodesis, and the most common way to do this, is by chemical means. The drug of choice in the United States has for many years been tetracycline, but since injectable tetracycline is no longer available, some substitute must be found. The substance that will "win" is not yet clear, but the two leading contestants are talc and doxycycline. Bleomycin also has its supporters, and a dark horse is quinacrine, which although not easily available in the United States, has been used in many European centers for decades. PMID- 9363077 TI - Diseases of the pleura. PMID- 9363076 TI - Disorders of pulmonary circulation. PMID- 9363078 TI - Cystic fibrosis. AB - Cystic fibrosis has only been recognized as a distinct clinical entity for less than 60 years. In that period of time, the median survival has improved from a few months to 29 years. This editorial review outlines the clinical multiorgan involvement of cystic fibrosis and current management strategies and introduces the comprehensive articles by the contributing authors of this section on the most rapidly evolving areas in cystic fibrosis. The discussion includes how the cystic fibrosis gene product, the cystic fibrosis transmembrane conductance regulator, produces lung disease; the relationship between genotype and phenotype; the factors that determine prognosis in cystic fibrosis; new treatment modalities for cystic fibrosis; lung transplantation; and the prospects for gene therapy in cystic fibrosis. With rapid advances in our clinical and genetic understanding of cystic fibrosis, it is projected that individuals born with cystic fibrosis today will live into their 40s. PMID- 9363079 TI - How do cystic fibrosis transmembrane conductance regulator mutations produce lung disease? AB - In recent years, several functions of the cystic fibrosis transmembrane conductance regulator have been discovered, yet the pathophysiology of the pulmonary disease in cystic fibrosis remains unclear. At the cellular level, functions of this protein include regulation of chloride and sodium transport at the cell membrane and in intracellular organelles, regulation of protein trafficking, and posttranslational processing of glycoconjugates. Elucidation of these functions has led to several hypotheses to account for how defects in the cystic fibrosis transmembrane conductance regulator produce pulmonary disease, but a clear understanding of the pathophysiologic links between the cellular functions of the cystic fibrosis transmembrane conductance regulator and organ dysfunction has been hampered by the lack of ideal model systems. Current evidence suggests that defects in the cystic fibrosis transmembrane conductance regulator lead to alterations in periciliary fluid homeostasis, mucus hydration, mucin secretion, and apical membrane protein structure. In turn, these alterations impair mucociliary clearance and promote bacterial infection, which then leads to chronic airway inflammation and the development of bronchiectasis. PMID- 9363080 TI - Prognosis in cystic fibrosis. AB - Prognosis for patients with cystic fibrosis has improved dramatically over the past three decades. In the United States, median survival age is now 28.9 years. Although genotype predicts exocrine pancreatic function, it does not correlate with pulmonary status or overall clinical outcome. However, there are a number of parameters, such as exocrine pancreatic sufficiency, male gender, absence of colonization with mucoid Pseudomonas aeruginosa, presentation with predominantly gastrointestinal symptoms, balanced family functioning and coping, and compliance with treatment regimens, that predict a more favorable outcome. The impact of early diagnosis and treatment is still controversial. Although nonblinded studies indicate decreased morbidity in the first 2 to 4 years of life among patients diagnosed by newborn screening, no data support long-term benefit in terms of pulmonary function or survival. With increased longevity, there is now evidence of a small but significantly increased risk of gastrointestinal tract cancer among patients with cystic fibrosis. PMID- 9363081 TI - The relationship between genotype and phenotype in cystic fibrosis. AB - Cystic fibrosis is characterized by a wide variability of clinical expression. The cloning of the cystic fibrosis transmembrane conductance regulator gene and the identification of its mutations has promoted extensive research into the association between genotype and phenotype. Several studies showed that there are mutations, such as delta F508 (the most common mutation worldwide), that are associated with a severe phenotype: early age at diagnosis, pancreatic insufficiency, poor nutritional status, high incidence of meconium ileus, and high sweat chloride levels; lung disease, however, is variable. The milder mutation is dominant over the severe mutation causing a milder phenotype. In vitro studies of cystic fibrosis transmembrane conductance regulator function suggested that different mutations cause different defects of protein production and function. Five mechanisms by which mutations disrupt cystic fibrosis transmembrane conductance regulator function have been suggested: class I mutations cause defective protein production, class II mutations are associated with defective protein processing, class III mutations are associated with defective regulation, class IV mutations are associated with defective conductance, and class V mutations include mutations affecting the level of normal messenger RNA transcript and protein required for normal function. This class might include mutations affecting correct splicing of pre-messenger RNA transcripts by either exon skipping or by inclusion of extra cryptic exons. PMID- 9363082 TI - New treatment modalities for cystic fibrosis. AB - Refinements in standard therapy for cystic fibrosis have led to dramatic increases in survival and quality of life over the past three decades. Standard therapy has consisted of oral and intravenous antibiotics, chest percussion with postural drainage, and aerosol bronchodilator therapy. The discovery of the cystic fibrosis gene and elucidation of the underlying biochemical defect have broadened our understanding of the pathophysiology of cystic fibrosis and provided a rationale for many new and innovative therapies. Modulation of airway epithelial ion transport may improve mucociliary clearance and delay colonization by infective organisms. Anti-inflammatory therapy may decrease lung injury that results from the host's attempt to limit airway infection. Supplementation of airway antiproteases may limit the destructive effects of unopposed proteases on pulmonary architecture. Genetic biotechnology has already produced agents that preserve pulmonary function and decrease infectious exacerbations by altering the viscoelastic properties of sputum from patients with cystic fibrosis. Both active and passive immunotherapy are currently being investigated as a measure to delay or combat endobronchial infection with Pseudomonas spp. Aerosolized aminoglycoside antibiotics are being increasingly employed to control pulmonary infection while minimizing systemic toxicity. These treatment modalities, combined with the prospects for gene therapy, provide a brighter outlook for the patient with cystic fibrosis than ever before. PMID- 9363083 TI - Lung transplantation in cystic fibrosis. AB - Since the mid-1980s, more than 500 isolated lung and more than 240 heart-lung transplantations have been performed in patients with cystic fibrosis and end stage disease. Survival data in these patients are now comparable to those of the general transplantation population as physicians have learned to deal successfully with many issues unique to patients with cystic fibrosis. Resistant infections and bronchiolitis obliterans remain significant obstacles to overcome in order to improve patients outcomes and enhance posttransplant quality of life. PMID- 9363084 TI - The prospects for gene therapy in cystic fibrosis. AB - Gene therapy provides the best prospect of a fundamental new treatment for cystic fibrosis. The lungs are the most important target, because this organ is the most severely affected by the disease and is also accessible for topical treatment. Advances in this field have been very rapid, and the prospects remain good although a number of problems need to be overcome. The two main approaches to gene transfer, namely adenoviruses and liposomes, are efficient in vitro, but early clinical trials have shown that they work less well in vivo. A number of proof of concept studies have shown that gene transfer is possible, but full functional correction of the cystic fibrosis defect has not yet been achieved. Adenoviruses have provoked an inflammatory response, and new viral vectors are being developed to overcome this. Existing lipids are relatively inefficient, but new liposomes are being developed to enhance gene transfer. Much work needs to be done to improve safety and efficacy of gene transfer before materials are ready for large scale clinical trials. However, progress is very rapid, and there is a real prospect of developing an effective gene therapy for cystic fibrosis within the next decade. PMID- 9363085 TI - Developing a strategy for care of sleep-disordered breathing. PMID- 9363086 TI - Epidemiology of obstructive sleep apnea syndrome. AB - Obstructive sleep apnea syndrome is the most common organic sleep disorder resulting in excessive daytime somnolence. It is almost as common as asthma. According to recent epidemiologic studies, the prevalence of obstructive sleep apnea syndrome is probably about 2% in women and somewhere around 4% in adult men in general. Many elderly people have the syndrome, and it is very common among patients who are morbidly obese, acromegalic, asthmatic; patients with arterial hypertension and heart disease, those with adult onset diabetes; and among patients with craniofacial abnormalities. In those groups, more than 30% or 40% of patients may have obstructive sleep apnea syndrome. Even more patients may have sleep apnea without daytime symptoms or partial upper airway obstruction during sleep. Among children, symptoms such as snoring and apneic episodes are relatively rare, but a high proportion of children with these symptoms have hypoxic respiratory events. Some recent methodologic issues and use of questionnaires are discussed. PMID- 9363087 TI - Hypersomnolence and neurocognitive performance in sleep apnea. AB - Two symptom clusters are prominent obstructive sleep apnea syndrome: excessive daytime sleepiness and neurocognitive difficulties. This article reviews studies that have attempted to determine the etiology and interrelation of these two symptom clusters. The research has clearly determined that the cause of the daytime sleepiness of obstructive sleep apnea syndrome is the fragmentation of sleep by the brief arousals that terminate each apneic event rather than the nocturnal hypoxemia that also occurs in obstructive sleep apnea syndrome. However, the daytime sleepiness and nocturnal hypoxemia appear to both contribute to the neurocognitive impairments of obstructive sleep apnea syndrome, and each seems to affect specific aspects of neurocognitive performance. The extent to which treatment reverses the neurocognitive impairments of obstructive sleep apnea syndrome is yet to be fully determined. The initial study suggests that the impairments are not completely reversed with treatment. PMID- 9363088 TI - Mechanisms of apnea. AB - Instabilities in breathing pattern are a common feature of sleep, giving rise to a variety of syndromes that vary in the magnitude of respiratory disturbance but that all lead to frequent arousals and sleep fragmentation. Although these syndromes vary in intensity of respiratory disturbance, the underlying mechanism of each is determined to a large extent on the neural processes that promote periodicities in net respiratory output. This review focuses on recent publications that have evaluated central brainstem processes for their involvement in the initiation and resolution of an apneic episode. In particular, this review focuses on several neural processes that can play an important role in promoting respiratory instability. These include spontaneous oscillations within the respiratory network, instability in the chemical control system due to increased gain in the feedback controller, differences in the controller gains of the upper airway and pump muscle effectors, state-dependent instabilities, and loss of stabilizing processes (eg, poststimulus potentiation.) PMID- 9363089 TI - Medical treatment of sleep apnea. AB - Obstructive sleep apnea is a common disorder. Since 1981 the treatment of choice has shifted from tracheostomy or weight loss to uvulopalatopharyngoplasty and then to continuous positive airway pressure. This review encompasses the most recent literature, focusing mainly on current treatment options and other potential and experimental modes of therapy. We review in detail continuous positive airway pressure therapy, including unwanted effects; compliance and possible ways to improve it; and ways to deal with the difficult patient. We also review dental appliances, electrical stimulation, and potential hormonal and nicotine treatment. PMID- 9363090 TI - Update on upper airway surgery for obstructive sleep apnea. AB - Uvulopalatopharyngoplasty has limited efficacy in treating obstructive sleep apnea, with excellent results achieved in fewer than half of patients who undergo this procedure. Attempting to select patients who have only retropalatal collapse of the pharynx increases the likelihood of a successful outcome. Although this type of patient selection has been attempted with various techniques, the validity of these approaches is not documented. Objective studies of the airway of awake and asleep patients with obstructive sleep apnea using fiberoptic flexible pharnygoscopy and manometry points to the disparity between observations and complexity of adequate assessment of the mechanism and pattern of pharyngeal collapse. Various approaches to treating the patient with obstructive sleep apnea surgically include uvulopalatopharyngoplasty, genioglossal advancement and hyoid myotomy and suspension, and maxillomandibular advancement. Results of these procedures vary in different reports, possibly due to variation in patient populations or surgical technique. Optimal treatment requires careful consideration of many patient variables and involves the use of a protocol that includes several surgical procedures. Laser-assisted uvulopalatoplasty lacks documentation of efficacy for patients with obstructive sleep apnea. The efficacy of this procedure is likely to prove very limited. Until its proper place in the surgical armamentarium is known, caution is warranted. PMID- 9363091 TI - Cardiovascular disease and sleep apnea. AB - A number of novel and important observations have recently arisen that emphasize the interaction between sleep apnea and cardiovascular function. New evidence of a role for obstructive sleep apnea as an independent factor in the genesis of hypertension and nocturnal myocardial ischemia has been described. Advances have been made in the understanding of the acute impact of sleep-disordered breathing on hemodynamic function, and a better understanding of the interaction between sleep-disordered breathing and congestive heart failure is now emerging. There is now strong evidence that reversal of sleep-related breathing disorders by nasal continuous positive airway pressure leads to improvements in markers of cardiovascular outcome in selected patients with congestive heart failure. These findings augur well for the development of new diagnostic approaches and treatment strategies for patients with sleep apnea and coexisting cardiovascular disease. PMID- 9363092 TI - Cystic fibrosis. PMID- 9363093 TI - Sleep and respiratory neurobiology. PMID- 9363094 TI - Interstitial lung disease. PMID- 9363095 TI - High-resolution computed tomography, magnetic resonance imaging, and positron emission tomography in interstitial lung disease. AB - In patients who have interstitial lung disease, chest radiography remains the primary imaging technique for both initial diagnosis and follow-up. For further investigation of selected patients the imaging modality of choice is currently high-resolution computed tomography. Magnetic resonance imaging and positron emission tomography have great potential in this field, particularly with respect to disease activity, but are still largely experimental and are not routinely employed. PMID- 9363096 TI - Current concepts in and modes for measurement of activity in interstitial lung disease. AB - Activity in interstitial lung disease is indicated by the progression of illness, but is neither an estimate of total disease nor can it be equated with the outcome or need for therapy. There is no unifying concept of activity or progression of disease that will fit the decision processes for all of interstitial lung disease. Great effort has been directed to identifying clinical indices, serum markers, bronchoalveolar lavage findings, and imaging techniques that predict activity or progression from single observations at the time of diagnosis, and thus allowing early recognition of patients who have differing natural history of disease. The past year has seen special emphasis on patient symptoms, initial results of pulmonary function tests, and especially high resolution computed tomography imaging at the time of diagnosis and the relation these factors have to disease progression, response to therapy, and survival. PMID- 9363097 TI - Wegener's granulomatosis. AB - Since its first description by Wegener in 1936, Wegener's granulomatosis has undergone significant changes in terms of clinical scope, diagnosis, and treatment. It is no longer tenable to insist on the fulfillment of the Wegener's triad to make the diagnosis. The wide range of clinical presentations is encompassed by the ELK (ear, nose, and throat; lung; kidney) classification in which any combination or singular involvement of the major sites can be considered within the Wegener's spectrum if supported by the appropriate pathologic findings or the presence of a cytoplasmic antineutrophil cytoplasmic antibody pattern. Treatment is based on the extent of involvement and clinical tempo. Trimethoprim-sulfamethoxazole may be used for patients with localized disease. Systemic disease, including involvement of the kidney, mononeuritis multiplex, and skin vasculitis, is treated with systemic glucocorticoids and cyclophosphamide. Research into the antineutrophil cytoplasmic antibody phenomenon is yielding new insights into possible pathogenic mechanisms. PMID- 9363098 TI - Pulmonary involvement in systemic lupus erythematosus. AB - Pulmonary disorders in systemic lupus erythematosus involve a variety of clinical presentations and pathologic patterns, which can be difficult to diagnose due to systemic dysfunction, infection, or complications of therapy. The causes of dyspnea in systemic lupus erythematosus are multifactorial, and the clinical manifestations of lung disease widely vary. Biopsy is frequently relied on to evaluate and diagnose pulmonary disease in systemic lupus erythematosus. The patient who has systemic lupus erythematosus-associated lung disease is effectively treated with various immunosuppressive drugs, in conjunction with careful evaluation of the patient's systemic involvement, drug-induced complications, and the ever-present threat of infection. PMID- 9363099 TI - Needle, transbronchial, thoracoscopic, or open lung biopsy in interstitial lung disease. AB - The specific diagnosis of interstitial lung disease has conventionally been determined by lung biopsy. Lung biopsy also is useful for assessing disease activity and prognosis, and is sometimes useful in deciding on the necessity of therapy. The availability of newer biopsy techniques and the interaction of these techniques with current generation imaging modalities has changed the role of biopsy in interstitial lung disease. This review reports on the indications, techniques, and limitations of biopsy procedures and places them in the context of the use of current imaging methods, as reflected in recent literature. PMID- 9363100 TI - HIV-related interstitial lung disease. AB - The progressive breakdown of the cell-mediated immunity, which characterizes the natural history of HIV infection, invariably leads to the development of miscellaneous opportunistic infections or neoplasms involving a number of tissues, including the respiratory tract. In particular, given the extent and the severity of most infectious complications, it is not surprising that respiratory failure is a common finding in patients who have AIDS-related interstitial lung disease. Extensive knowledge of the sequence of events that starts with HIV infection of CD4+ cells and leads to the development of respiratory complications has been recently achieved. The present understanding of the pathogenesis of AIDS related interstitial lung disease comes from the evaluation of cell populations retrieved from bronchoalveolar lavage fluid. In particular, the information gained from bronchoalveolar lavage studies led to the realization that HIV strains are present in the respiratory tract of HIV-seropositive subjects at all stages of infection. Furthermore, the characterization of bronchoalveolar lavage fluid cells proved to be central in evaluating the striking local immunologic reactions that can be detected in the lungs of these patients. Bronchoalveolar lavage studies have also demonstrated that local protective mechanisms may cause the shift toward accelerated progression to AIDS and the development of respiratory failure. This reviews briefly examines clinical aspects and cellular patterns of HIV infection in the respiratory tract. We will also consider data showing that HIV infection evokes an inflammatory response, initiated and sustained by cytotoxic T lymphocytes and macrophages and mediated by a number of cytokines that amplify host defenses as well as facilitate the spread of the retrovirus throughout the lower respiratory tract. PMID- 9363101 TI - Diagnosis, pathogenesis, and treatment of sarcoidosis. AB - Sarcoidosis is a commonplace multisystem disorder characterized by the presence of noncaseating granulomas. Although the clinical syndrome of the disease is recognized throughout the world, the pragmatic understanding of its diagnosis and management remains poorly understood and controversial. Much of the frustration experienced in elucidating its pathogenesis is directly related to our inability to find the cause of the disease. This review provides a brief and practical discussion of the diagnosis, pathogenesis, and concept of disease activity. It also recommends guidelines for management based on available clinical, immunologic, and radiologic information enhanced by our experience at the University of Southern California during the past 30 years. PMID- 9363102 TI - Lung transplantation in interstitial lung disease. AB - A discussion of transplantation as an optional therapeutic modality for patients with end-stage interstitial lung disease follows. Single lung transplantation for pulmonary fibrosis has been shown to be a successful modality with good survival rates. A limited cadaveric donor pool has affected the number of patients who can undergo transplantation. Selection criteria have been established to identify the most appropriate candidates. Transplantation of lung lobes obtained from living related donors has recently been performed successfully in a patient suffering from pulmonary fibrosis. Living-related donors can potentially increase the donor pool. Successful transplantation of sarcoidosis patients is clearly possible. Recurrence of sarcoidosis in the lung allograft has been recognized but the clinical significance is not yet clear. PMID- 9363103 TI - Pulmonary Langerhans cell granulomatosis. AB - Pulmonary Langerhans cell granulomatosis (LCG), also called histiocytosis X, is characterized by the presence of destructive granulomas containing large numbers of Langerhans cells. The lesions are almost exclusively centered on distal bronchioles, and it may be more accurate to consider the disease as a bronchiolitis. Isolated pulmonary LCG is an uncommon disease that usually affects young adult smokers. Multifocal or diffuse involvement can also occur, though more often in infants or children. High-resolution computed tomography has proved to be useful in the diagnosis of the disease by allowing the identification of characteristic cystic lesions associated with nodules. Bronchoalveolar lavage strongly supports the diagnosis in only the occasional patient. The pathogenesis of pulmonary LCG remains unknown, although several arguments suggest that, at least in adults, it may result from an uncontrolled immune response initiated by Langerhans cells. Granulocyte macrophage colony-stimulating factor could be one of the factors responsible for the local accumulation of Langerhans cells in early lesions. Recently, evidence that lesional Langerhans cells are of clonal origin has been reported in patients who have various forms of the disease, but this finding has not yet been shown for pulmonary LCG. Further studies are needed to determine whether the pathogenetic mechanisms are different in patients who have localized or diffuse forms of the disease. PMID- 9363104 TI - Lymphangioleiomyomatosis. AB - Pulmonary lymphangioleiomyomatosis is an uncommon chronic debilitating disorder of unknown etiology afflicting women of childbearing age, characterized histologically by proliferation of atypical smooth muscle cells in the lung. The clinical features of lymphangioleiomyomatosis can be typical, with airflow limitation, diffuse pulmonary infiltrates on chest radiograph, and numerous lung cysts on computed tomogram of the chest. Diagnosis has been made by open lung biopsy often in connection with pneumothorax. Recently, histologic diagnosis was confirmed by transbronchial biopsy results. Hormonal manipulation therapy had beneficial effects on chylothorax or chylous ascites, whereas pulmonary parenchymal changes appeared to be stationary or progressive. Several prognostic factors were reported among pulmonary function data and histologic findings of open lung biopsy specimens. PMID- 9363105 TI - Interstitial lung disease. PMID- 9363106 TI - Transplantation. PMID- 9363107 TI - Granulomatosis and vasculitides of the respiratory tract. PMID- 9363108 TI - Recent advances in the treatment of asthma. PMID- 9363109 TI - The epidemiology of asthma. AB - There are wide variations in the prevalence of asthma among different countries, but the epidemiologic evidence suggests that most variations are due to environmental and not genetic factors. In recent years, major advances have been made toward quantifying the risk associated with certain environmental factors, particularly allergen exposure, diet, and indoor and outdoor air pollutants, and with genetic factors, i.e., gender and a parental history of allergic disease, that are involved in causing asthma. It is hoped that this knowledge will be helpful in the design of interventions to reduce the incidence of asthma in the next generation of children. In the meantime, it is encouraging that advances in measuring allergen levels are now leading to the documentation of the clinically important sources of allergens and the effectiveness of avoidance measures. PMID- 9363110 TI - Self-management and other behavioral aspects of asthma. AB - We review recently published literature on behavioral aspects of asthma, including program descriptions, reviews, and original research reports. Most of the literature on behavioral aspects of asthma has been in the area of self management, including education, medication use, and peak flow monitoring. Recent studies of these factors have shown promising trends in reducing morbidity and in improving health care utilization outcomes. Medication adherence continues to be problematic, and its complexity is increased when comparing inhaled with oral medications and bronchodilators with anti-inflammatory agents. Psychobiologic factors that have been recently studied include perceptions of airway changes and the role of emotional responses in asthma self-management. Because the behavioral aspects of asthma play such a significant role in asthma treatment, further study is needed to determine how changes in patient behavior can improve patient quality of life. PMID- 9363111 TI - Mechanisms of asthma. AB - In recent years, our understanding of basic mechanisms of asthma has increased significantly. This article reviews three specific areas that have been the focus of current asthma research: the role of nitric oxide in the control of airway tone and inflammation, mechanisms of exercise-induced asthma, and current studies in the genetics of asthma. Recent advances in each of these areas have contributed to a better understanding of the pathophysiologic mechanisms in asthma and are important in the diagnosis and therapy of this disease. PMID- 9363112 TI - The role of allergy and atopy in asthma. AB - Asthma has become a very common disease and despite new treatments continues to cause very large numbers of hospital admissions, school absences and so on. Recent evidence from many parts of the world has established that the single most important risk factor for perennial asthma is sensitization to one of the major indoor allergens: dust mite, cat, dog, or cockroach. However, there is also striking evidence about the role of rhinoviruses and ozone as enhancers of the immune response. Over the past 2 years, the ways in which these enhancers interact with the primary immune response both to cause asthma and to influence the severity of the disease have started to become clear. PMID- 9363113 TI - New developments in bronchodilator therapy. AB - Generally favorable literature was published regarding the contributions of bronchodilators to asthma therapy. Analysis of asthma mortality data suggested that the risk of death from asthma was primarily associated with the use of fenoterol rather than beta-adrenergic bronchodilators as a class, or reflected the severity of the underlying asthma, which resulted in increasing beta-agonist use. Salmeterol was shown to outperform oral beta-adrenergic agonists and individual dose-titrated theophylline in controlling asthma symptoms while causing fewer adverse effects. When salmeterol was added to low-dose inhaled corticosteroids, the combination outperformed moderate-dose inhaled corticosteroids alone. Regular use of salmeterol, but not albuterol, improved the quality of life for patients with asthma to a clinically significant degree. Finally, theophylline, at relatively low blood levels, was clearly shown to improve asthma control, even in patients receiving moderately high-dose inhaled corticosteroids. More importantly, this symptomatic response was accompanied by decreases in activated lymphocytes, eosinophils, and proinflammatory cytokines in bronchial biopsy results. PMID- 9363114 TI - Clinical aspects of anti-inflammatory therapy in asthma. AB - Anti-inflammatory therapy is now considered first-line treatment for mild to moderate asthma. Corticosteroids remain the most potent anti-inflammatory therapy available (although their mode of action is not clearly understood), and recent investigations suggest that earlier institution of anti-inflammatory therapy may be more beneficial than delayed therapy in newly diagnosed asthmatic patients. Inhaled corticosteroids have far fewer adverse effects than their oral counterparts; however, their risks must be carefully considered before use in mild asthma. These drugs can cause alterations in the hypothalamic-pituitary adrenal axis, alter bone metabolism, and suppress growth in children. The potential long-term risk of these alterations remains the topic of much debate. PMID- 9363116 TI - Clinical aspects of asthma. AB - Asthma, one of the most common medical conditions during pregnancy, provides health care workers with an opportunity to diagnose, educate, and treat these patients. With proper fetal and maternal monitoring, outcome is good both for the mother and the baby. Elderly patients constitute a special group for whom asthma is underdiagnosed and undertreated. Exercise is a common trigger for asthma. The three factors determining exercise-induced asthma are minute ventilation, climatic conditions, and bronchial hyperreactivity. In vocal cord dysfunction, abnormal adduction of vocal cords causes airway obstruction. Vocal cord dysfunction can occur by itself or along with asthma and can be mistaken for asthma. PMID- 9363115 TI - Nocturnal asthma: physiologic determinants and current therapeutic approaches. AB - Asthma has a tendency to destabilize at night in patients that are diurnaly active and try to sleep at night. As asthma worsens, the expression of this disease seems to increase at night. Additionally, nocturnal asthmatics have increased airway hyperresponsiveness and likely more active inflammation at night as compared with the daytime. Although the cause of nocturnal asthma cannot be completely explained, there do appear to be a variety of internal body circadian rhythms that play a role in this disease. Also, noncircadian rhythmic influences such as sleep, supine posture, snoring, and gastroesophageal reflux cannot be dismissed. Directing therapy, perhaps in unique ways, may be essential for the control of nocturnal asthma. Patients on inhaled corticosteroid therapy or nonsteroidal anti-inflammatory agents often persist in asthmatic disease expression at night. Long-acting bronchodilator therapy, either by inhalation or with sustained-release tablets, is often added to inhaled anti-inflammatory therapy for more complete 24-hour disease control. Using existing therapies but employing chronotherapeutic strategies is likely to improve the overall asthma management. By focusing on nocturnal asthma, we may be able to improve our understanding of this disease and more effectively control it over each 24-hour period. PMID- 9363117 TI - Emergency treatment of asthma. AB - Rapid and directed evaluation of the acutely ill patient with asthma allows for the assessment of severity of obstruction. Aggressive therapy with inhaled beta agonists, corticosteroids, and supplemental oxygen remains the cornerstone of therapy for patients presenting to the hospital. Patients demonstrating an incomplete response to inhaled beta-agonists will require inhaled anticholinergics and may benefit from subcutaneous epinephrine or terbutaline. Theophylline should be continued in all patients who are chronically maintained on this medication and may benefit patients admitted to the hospital for a serious exacerbation. Deterioration or failure to improve despite optimal treatment identifies those patients who are likely to require mechanical ventilation and who should be closely observed in the intensive care unit. PMID- 9363118 TI - Assessment of peak expiratory flow in asthma. AB - Assessment of peak expiratory flow is a test of airway caliber that is simple, inexpensive, and easily performed on an outpatient basis. Because asthma is characterized by fluctuations in airway caliber, such a test can be useful in the diagnosis and assessment of the condition's severity. Although this approach is useful, it has several pitfalls: peak expiratory flow is less sensitive than forced expiratory volume in 1 second in the assessment of airway caliber; compliance with daily assessment on a long-term basis is generally not satisfactory; and daily monitoring of airway caliber may not be more sensitive than symptoms recorded in a diary to identify flare-ups. Peak expiratory flow may be a useful means of asthma assessment for subjects who either under- or over estimate their symptoms, if the tests are conducted over short intervals of monitoring, and specifically in the investigation of occupational asthma. PMID- 9363119 TI - Asthma. PMID- 9363120 TI - The Lung Health Study. PMID- 9363121 TI - The worldwide epidemiology of chronic obstructive pulmonary disease. AB - Chronic obstructive pulmonary disease (COPD) is common and increasing in prevalence in North America and other industrialized areas. The worldwide epidemiology is multifactorial and complex. Smoking is by far the most important and correctable risk factor. Heredity and environmental risks also relate to the pathogenesis of COPD. Early stages of COPD can only be identified by spirometry. Smoking cessation can retard the progress of the disease and improve prognosis. Reduction or elimination of environmental risks may also be helpful. PMID- 9363122 TI - Bullous emphysema. AB - Bullae are usually associated with varying degrees of emphysema, and bullous emphysema may be an appropriate term for bullous diseases. Recent advances in high-resolution computed tomography and thoracoscopic surgery allow us to improve both our knowledge of as well as the surgical outcomes for bullous emphysema. However, the etiology and pathogenesis of bullae and their association with emphysema are not yet elucidated. Further investigation, including animal studies, may be helpful in solving the questions from the perspectives of etiology, pathology, and function in bullous emphysema. PMID- 9363123 TI - Lung reduction surgery for emphysema. AB - Lung reduction surgery, a procedure that entails removal of portions of the most diseased lung tissue in patients with diffuse emphysema, has been resurrected based on advances in surgical technique, radiographic imaging, and pulmonary physiologic assessment. We outline potential mechanisms for improvement in pulmonary mechanics, gas exchange, pulmonary vascular function, and exercise tolerance following surgery. Available literature is reviewed, and patterns that are beginning to emerge with respect to optimal surgical approach and patient selection criteria are presented. Early results suggest that this procedure offers real hope to our patients; however, long-term follow-up studies will be necessary to define its ultimate utility. PMID- 9363124 TI - Reactive airways dysfunction syndrome. AB - Two types of occupational asthma have been identified and are distinguished by whether they appear after a latency period. Asthma without a latency period is best illustrated by irritant-induced asthma. The reactive airways dysfunction syndrome is a subset of irritant-induced asthma. Although case reports appeared in the literature before 1985, the term reactive airways dysfunction syndrome was coined in 1985. Since that report a number of case reports of asthma-like illnesses developing as the direct consequence of massive toxic inhalation exposure have been published. Not all experts, however, are certain that reactive airways dysfunction syndrome is a real and distinct clinical entity. Most studies and reviews, although acknowledging the current gap in our knowledge of the epidemiology, pathogenesis, and pathologic findings, conclude that the available scientific evidence supports the conclusion that reactive airways dysfunction syndrome and irritant-induced asthma are valid disorders. PMID- 9363125 TI - Acute respiratory failure in chronic obstructive pulmonary disease. AB - Clinically significant chronic obstructive pulmonary disease is a common and important disorder in the United States. As many as 15 million individuals suffer from chronic obstructive pulmonary disease, many of whom have disease requiring hospital or ICU admission. Acute respiratory failure in patients with chronic obstructive pulmonary disease is one of the most common causes of admission to the ICU for this patient population. In this article I address common issues regarding diagnosis and management of acute respiratory failure in chronic obstructive pulmonary disease. Acute respiratory failure will be defined as well as the common and unusual etiologies of acute respiratory failure. Pharmacologic and nonpharmacologic treatment will be addressed, especially the ventilatory treatment of the intubated patient with chronic obstructive pulmonary disease. Special attention has been made to included the most recent investigations regarding diagnosis and treatment of the patient with chronic obstructive pulmonary disease and respiratory failure. PMID- 9363126 TI - The pneumoconioses. AB - The stringent industrial hygiene regulations that have been introduced in North America, Europe, and Australasia have led to a decline in the incidence and prevalence of silicosis, coal workers' pneumoconiosis, and asbestosis. Although new cases of asbestosis are not occurring, an appreciable number of mesotheliomata are still being diagnosed, and there has yet been little, if any, decline in the latter tumor. These new cases are nearly entirely due to exposure to amphiboles in the 1940s and 1950s. It is expected that by about the year 2000 the incidence of mesothelioma will begin to decrease in the United States and Canada. Meanwhile there is an undue preoccupation with more and more sensitive methods of detecting asbestosis, silicosis, and coal workers' pneumoconiosis, eg, magnetic resonance imaging, bronchoalveolar lavage, and so forth. Much effort is being made in trying to detect disease in groups of workers with extremely low exposures and no symptoms. Smaller and smaller effects are being detected, with the ultimate aim appearing to be detecting nothing at all. Efforts should be made at surveying other populations exposed to agents that have recently been introduced and that could conceivably have long-term effects. PMID- 9363127 TI - An update on air pollution. AB - Air pollution is associated with adverse health effects. Much of the recent literature, which is the focus of this review, has concentrated on identifying individuals at risk and on the health effects of mixed pollutants. For indoor air, new analyses continue to support the notion that the risk of residential radon exposure is low and that environmental tobacco smoke may cause respiratory symptoms and dysfunction in adults, especially asthmatic adults, as well as in children. For outdoor air, the long-term effects of ozone exposure remain unclear, despite evidence of inflammation and small airway dysfunction after acute exposure. Ozone may increase the sensitivity of asthmatic patients to allergens. Increased morbidity in association with increasing particulate matter levels gives coherence to the argument that the relationship between particulate matter and mortality is causal. However, other investigators note the tight associations among outdoor pollutants and consider particulate matter a marker of air pollution levels. PMID- 9363128 TI - The respiratory effects of passive tobacco smoking. AB - Smokers not only increase their own risk of pulmonary disease, but contribute to the health risk of nonsmokers through the production of environmental tobacco smoke. Evidence continues to build regarding the positive association between passive smoking and increased risk of respiratory symptoms and lung diseases. Environmental tobacco smoke exposure has been implicated in both the development and worsening of airway hyperresponsiveness and wheezing. Pulmonary function reduction has been documented in children with both prenatal and postnatal exposure, but the presence of increased airway obstruction and its long-term significance is unclear in adults. There is growing concern about the risk of lung cancer, particularly among female never-smokers exposed to tobacco smoke in the home and workplace. Environmental tobacco smoke is a major component of indoor air pollution and a major public health threat. Most importantly, it is a preventable risk and efforts to control and eliminate exposure need to be encouraged. PMID- 9363129 TI - Bronchiolar disorders with airflow obstruction. AB - Bronchiolar lesions continue to be increasingly recognized as a cause of airflow obstruction. Thus, it is important to have a current update of the current clinical, radiographic, and immunologic perspective of these disorders. Diffuse panbronchiolitis has been reported to occur in the United States and Europe, and the anti-inflammatory action of erythromycin appears to be effective in management. Idiopathic bronchiolitis obliterans, post-fume or post-infectious, or connective tissue disorder bronchiolitis obliterans continues to be rare and often has a poor prognosis. Lung transplantation bronchiolitis obliterans continues to be the major complication and cause of mortality in transplant recipients. Risk factors of this form of chronic rejection include more frequent and more severe acute rejection and the coexistence of organizing pneumonia. The recognition of the distinctive differences among the bronchiolar airflow disorders continues to be essential for improved patient care, greater understanding of the pathogenesis, and development of therapeutic advances. PMID- 9363130 TI - Management of chronic obstructive pulmonary disease. AB - Chronic obstructive pulmonary disease is the fourth leading cause of death in the United States, affecting approximately 10% of all adults. Several articles published during the past year contributed significantly to our understanding of the complicated management of this disease. New information concerning bronchodilators, antibiotic therapy, mechanical ventilation, pulmonary rehabilitation, nutrition, and lung transplantation will help physicians further refine the care delivered to these patients. PMID- 9363131 TI - Diagnosis of chronic obstructive pulmonary disease and differentiation from asthma. AB - In the primary care setting, asthma and chronic obstructive pulmonary disease are common clinical challenges, which together affect approximately 25,000,000 Americans. As our therapeutic strategies for these two diseases diverge, it becomes important to distinguish between them. Although this may be relatively easy at the extremes of age using a combination of history and physical examination, this review focuses on additional information that may allow diagnostic distinctions to be made in the troublesome middle ground. PMID- 9363132 TI - Lung disease due to alpha 1-antitrypsin deficiency. AB - The association between alpha 1-antitrypsin deficiency and heritable emphysema was discovered in 1963. Subsequent epidemiologic evidence suggested that a serum alpha 1-antitrypsin level of 11 mumol/L (about 80 mg/dL by the still-used "commercial standard"), which is about 35% of the normal level, represents a "threshold" value, below which the risk of developing emphysema is increased and above which the emphysema risk is not increased. Recently, the ability to isolate and purify the alpha 1-antitrypsin protein from human blood has made "specific" augmentation therapy possible. Intravenous infusion of alpha 1-antitrypsin raises serum and alveolar levels above the putative thresholds, but clinical efficacy (i.e., decreased rate of decline in lung function and/or improved survival) remains presumptive. Based on available evidence, the American Thoracic Society recommends augmentation therapy for individuals with both a documented severe deficiency of alpha 1-antitrypsin and fixed airflow obstruction. PMID- 9363133 TI - Obstructive, occupational, and environmental diseases. PMID- 9363134 TI - Guidelines for the management of respiratory infection: why do we need them, how should they be developed, and can they be useful? AB - The management of respiratory infections is a complex and dynamic process, with many areas of controversy and numerous unresolved questions. In an apparent effort to deal with these issues, guidelines for care are being developed for a variety of infections including bronchitis, community-acquired pneumonia, hospital-acquired pneumonia, tuberculosis, HIV infection, and viral illness in immune-compromised patients. As the era of managed care approaches, guidelines will continue to emerge, and several questions about their utility must be answered. In this discussion, the rationale for the popularity of guidelines is examined, along with a review of the processes by which they are developed. Although evidence-based medicine has been suggested as a basis for this process, there are several problems with this approach. Most importantly, evidence-based medicine does not adequately allow for the incorporation of local experience, which is so vital in the management of respiratory infection because of the variability in bacteriology and antimicrobial susceptibilities in different practice settings. If a guideline is developed by a consensus of experts, and viewed as an hypothesis that can be modified based on local data collection, then it can be very useful and can lead to a number of potential benefits for patients with respiratory tract infection. PMID- 9363135 TI - Pathogenesis of respiratory infections and host defenses. AB - At the cellular level, the respiratory tract has a variety of defense mechanisms to prevent bacterial infection. Recent data have demonstrated that the respiratory epithelium plays a very active role in host defense. In this review we start by examining the respiratory epithelia and its function in mucociliary clearance, and extend our review to include its role in the secretion and regulation of inflammatory cytokines and production of antimicrobial factors. Furthermore, we examine how recent advances in understanding cystic fibrosis have provided useful insights into the pathogenesis of lower respiratory tract infection. In addition, we examine how two common respiratory pathogens, Streptococcus pneumoniae and Pseudomonas aeruginosa, subvert the defense mechanisms at the cellular level. Finally, we attempt to identify new or potential therapeutic approaches that have arisen from some of the insights into the pathogenesis of lower respiratory tract infections. PMID- 9363137 TI - Infective pathogenesis and outcomes in chronic bronchitis. AB - Bacterial infection is an important cause of exacerbations of chronic bronchitis, which can precipitate both direct toxic and host-mediated inflammatory bronchial epithelial damage. Repeated episodes, especially when caused by Haemophilus influenzae (the major pathogen) may be associated with more rapid deterioration in respiratory function. Criteria to identify patients with more severe disease and those who require either hospitalization or intensive care have been developed and can improve mortality. Antibiotic therapy has an accepted place in management, and predictors of the outcome of exacerbations have now been developed that allow severity staging of individual episodes. Nevertheless, despite the recognition of excessive failure rates due to increasing bacterial resistance and poor respiratory kinetics, many patients continue to receive empiric therapy with amoxicillin and other oral beta-lactams. Less empiric management guidelines, produced in Europe and North America and based on such criteria, now provide a framework for rational prescribing. Perhaps more importantly, it is now possible to design and perform placebo- and comparator controlled studies of new antibacterials, such as the fluoroquinolones and azalides, with improved potency and kinetic properties. This will enable both an assessment of their place in the management of exacerbations in at-risk patients with severe disease and an evaluation of their longer-term role in the prevention of a decline in respiratory function consequent upon repeated and ineffectively treated exacerbations. PMID- 9363136 TI - New pathogens for respiratory infections. AB - The emergence of new pathogens and the increasing antimicrobial resistance patterns of old pathogens are contributing factors to the high epidemiologic impact of lower respiratory tract infections. Hantaviruses, Chlamydia pneumoniae, and penicillin-resistant Streptococcus pneumoniae have recently gained most of the attention of international researchers. Hantavirus pulmonary syndrome has been confirmed in 100 cases with a very high mortality (52%). Risk factors for infection are peridomestic cleaning, agricultural activities, and an increased number of small rodents like deer mouse, mainly Peromyscus maniculatus. Pulmonary capillary leak and multiorgan involvement characterise Hantavirus pulmonary syndrome. Most recent reports rank C. pneumoniae among the three most common etiologic agents in community-acquired pneumonia, but it is also involved in chronic diseases such as chronic obstructive pulmonary disease and asthma. Several recent reports indicate the striking increase of penicillin-resistant S. pneumoniae strains. These data emphasize the crucial need for new therapeutic agents and more effective prevention programs. PMID- 9363138 TI - Severe community-acquired pneumonia. AB - Community-acquired pneumonia is an important public health concern and a recent focus of clinical practice guidelines. What has become clear from this renewed focus of attention is that a subgroup of patients with community-acquired pneumonia have severe disease with a differing spectrum of pathogens and prognosis. This article reviews the definition, bacteriology, diagnostic approach, and treatment of patients categorized as having severe community acquired pneumonia. Although some of what is discussed is controversial and the literature in this area continues to expand, we focus on an evidence-based approach to this clinical problem. PMID- 9363139 TI - Pneumonia in the elderly. AB - The incidence of pneumonia for elderly persons living in the community is 14 cases/1000 persons/y, whereas 33/1000 nursing home residents require hospitalization for pneumonia each year. Premorbid health status is more important than age in determining outcome from pneumonia in this age group. Two studies of mortality in the 2 years following pneumonia gave conflicting results. One study showed that the mortality rate was twice that which was expected. Both the clinical and radiographic diagnosis of pneumonia may be difficult in the elderly especially if there is co-existing congestive heart failure. Aspiration is an under-diagnosed cause of pneumonia in the elderly. Data from three randomized clinical trials indicate that intravenous antibiotic therapy can be changed to oral therapy when the patient has been afebrile (< 37.5 degrees C) for 16 hours, can take antibiotics by mouth, and has a leukocyte count returning towards normal. Adjunctive therapy with nutritional supplements and vitamin C may improve outcome in this group of patients. Yearly immunization with influenza A and B virus vaccine will reduce both the incidence of pneumonia and the rate of hospitalization for this infection. A discussion of pneumonia in the elderly is often divided into community-acquired pneumonia, which is treated at home or in a nursing home, or community-acquired pneumonia requiring hospitalization and nosocomial pneumonia. The latter is not described in this review. PMID- 9363140 TI - Diagnosis and management of thoracic empyemas. AB - Parapneumonic effusions are frequent complications of bacterial pneumonia. Depending on the severity of the underlying pneumonia, the promptness of antibiotic therapy, and the virulence of the infecting organism, 5% to 50% of patients will require pleural fluid drainage to prevent progression to an empyema. The decision to drain the pleural space depends on multiple clinical, laboratory, and radiographic factors. Delayed drainage results in pleural loculations, prolonged hospitalizations, and increased mortality. Image-guided percutaneous chest catheters provided an effective method for draining both free flowing and loculated effusions. Fibrinolytic agents are gaining wider acceptance for promoting drainage of loculated, viscous pleural fluid although randomized studies do not exist. Patients failing a chest tube drainage method should undergo early evaluation for an open surgical procedure. PMID- 9363141 TI - Nosocomial pneumonia. AB - Nosocomial pneumonia remains a major cause of morbidity, mortality, and significant hospital cost despite continued refinements in antimicrobial treatment, improved methods for diagnosis, and better supportive and preventive measures. While clinical experience is considerable, appreciation of the epidemiologic and pathogenic factors responsible for NP development and pathogen selection are limited, and consensus regarding optimal prevention and diagnostic and therapeutic strategies is lacking. This article reviews the recent literature with an emphasis on significance, pathogenesis, etiology, and therapy of nosocomial pneumonia. PMID- 9363142 TI - Diagnosis of pneumonia. AB - The multitude of studies on the diagnosis of pneumonia published in the past year testifies to the fact that the best diagnostic strategy remains undefined. For community-acquired pneumonia, the etiologic agent can be diagnosed in a high percentage of patients if extensive serologic testing is used. Unfortunately, standard diagnostic tools, including blood cultures, have a low yield. Newer diagnostic techniques offer some hope for an etiologic diagnosis at a time when therapeutic decisions can be made. For nosocomial pneumonia in the nonventilated patient, transthoracic needle aspiration appears to have good accuracy with a low complication rate. For ventilator-associated pneumonia, research on diagnostic methods has yielded important insights into the disease process itself. Unfortunately, consensus regarding the most appropriate diagnostic tool has not been achieved. PMID- 9363143 TI - Antimicrobial approaches to therapy for pneumonia. AB - Pneumonia remains a serious illness with significant associated morbidity and mortality. Parallelling our increased understanding of the etiology, epidemiology, and pathogenesis of pneumonia and the development of new antibiotics has been the frightening increase in the rate and extent of bacterial resistance. The prevalence of resistance has reached unprecedented levels in many countries, and we are facing the specter of infection by pathogens for which we have no effective treatment. To better understand some of the newer developments in this field, the discussion centers around the interactive triad of the host, pathogen, and drug. Pertinent developments relevant to each of these three areas are considered, along with a discussion of their clinical impact. PMID- 9363144 TI - Prevention of community-acquired and nosocomial pneumonia. AB - Pneumonia is an important cause of morbidity and mortality in the United States. The provision of effective prophylaxis for pneumonia has become a major goal for both public health officials and individual physicians. Prophylaxis for community acquired pneumonia is pathogen-specific and is directed toward the most common microorganisms that cause it. The 23-valent pneumococcal polysaccharide vaccine; the trivalent influenza vaccine; the Haemophilus b conjugate vaccine; and either trimethoprim-sulfamethoxazole, dapsone, or aerosolized pentamidine are recommended to prevent Streptococcus pneumoniae, influenza viruses, H. influenzae type b, and Pneumocystis carinii respectively. Except for the microorganisms listed above, the prevention of nosocomial pneumonia is not pathogen-specific. Rather, prevention of nosocomial pneumonia requires the use of infection control procedures, including patient and staff education; isolation of patients with highly contagious respiratory pathogens; vigorous hand washing; cleaning and sterilizaton of respiratory equipment; and use of sterile water in nebulizers and humidifiers. It also requires procedures to limit pooling and aspiration of secretions, such as positioning and rotation of the bed-bound patient; frequent suctioning of respiratory secretions using gloves and sterile suction catheters; and limiting enteral alimentation. Finally, selective decontamination of the digestive tract may be considered for intubated patients. PMID- 9363145 TI - Tuberculosis reemerges: the captain remains aboard. AB - The resurgence of tuberculosis and the emergence of multidrug resistant tuberculosis have led to renewed interest in this ancient disease. Advances in the field of molecular biology have increased our understanding of the epidemiology and transmission of infection. This has had a particular impact on the documentation of, and the subsequent development of guidelines to prevent, the nosocomial transmission of tuberculosis. Molecular techniques have dominated the efforts of investigators to improve diagnostic methods and therapeutic options. Recent information regarding the mechanism of developing protective immunity to tuberculosis may lead to the development of more effective vaccines and a role for immunotherapy in treatment. National and international organizations have formulated guidelines for the diagnosis and treatment of disease and infection. The development of a global response to the problem of tuberculosis in order to ensure the establishment of long-lasting control is needed. PMID- 9363146 TI - Respiratory infections in patients with HIV infection. AB - Changes in epidemiology have influenced the spectrum of pulmonary diseases in HIV infected populations. The increasing proportion of patients with AIDS who are intravenous drug users and members of racial or ethnic minorities correlate with increasing cases of bacterial pneumonia and tuberculosis. Both of these infections also occur more frequently with advanced immunosuppression. Antipneumocystis prophylaxis is also reducing the incidence and mortality rate from this infection, but when respiratory failure occurs with Pneumocystis carinii pneumonia, the mortality rate is high. Immunosuppression due to HIV causes active tuberculosis in many, and tuberculosis appears to accelerate the course of HIV disease. Directly observed therapy of tuberculosis has made a major impact on the incidence and cure rates of tuberculosis in areas of high prevalence. Pulmonary disease has been a major cause of illness and death in patients with HIV infection since the beginning of the AIDS epidemic. Early in the epidemic, P. carinii pneumonia was considered the predominant pulmonary disorder. However, epidemiologic shifts and advances in treatment have broadened our perspective on the diseases that patients with HIV infection develop. PMID- 9363148 TI - Infectious diseases. PMID- 9363147 TI - Respiratory infections in HIV-negative immunocompromised patients. AB - The number of immunosuppressed patients is increasing, with many being managed by community physicians. Encouraging success in vaccinating some patients with Hodgkin's disease against encapsulated organisms has been reported. The significance of and management of tuberculosis in solid organ transplants is being defined. Fungal infection remains a problem, but pathogenesis and treatment are being clarified. The overall incidence of Pneumocystis carinii pneumonia is low, but it is being seen in patients without malignant disease, especially those with Wegener's granulomatosis. Many authors have tried to establish risk factors that will allow development of clear indications for prophylaxis in these patients. New approaches to cytomegalovirus infection are discussed as well as the role of community-acquired viruses in causing disease in the immunosuppressed population. PMID- 9363149 TI - Predicaments in and prospects for lung cancer. PMID- 9363150 TI - Imaging in lung cancer. AB - The diagnosis, staging, and follow-up of lung cancer is a clinical and therapeutic challenge. Recent radiographic advances are critical to the management of patients with lung cancer. This review focuses on state-of-the-art chest imaging modalities, including plain radiography, computed tomography; magnetic resonance imaging, as well as the newest technique, positron-emission tomography, and discusses the current literature. PMID- 9363151 TI - Bronchoscopic, photodynamic, and laser diagnosis and therapy of lung neoplasms. AB - The use of lasers in the diagnosis and treatment of lung neoplasms has just surpassed a 20-year experience. This paper reviews recent developments in the use of lasers in the palliative treatment of advanced tracheobronchial tumors and pleural mesothelioma. The role of bronchoscopic laser therapy relative to other endobronchial treatment modalities such as stent placement and brachytherapy is presented. Finally, the potential use of lasers in photodetection and curative treatment of early lung cancer is discussed. PMID- 9363153 TI - Recent advances in chemotherapy for lung cancer. AB - Chemotherapy has produced only modest survival benefits in patients with advanced non-small cell lung cancer. Several new chemotherapeutic agents developed in the past few years have shown promising activity in non-small cell lung cancer. It is likely that these agents, used alone or in combination, will further improve the outcome for patients with advanced non-small cell lung cancer. Chemotherapy has made a much stronger impact in small cell lung cancer, but the majority of patients still die from disease. The new chemotherapeutic agents may also contribute to improved survival of patients with small cell lung cancer, especially when used in combination with thoracic radiotherapy in those who present with limited disease. PMID- 9363152 TI - Surgical aspects of non-small cell lung carcinoma. AB - Lung cancer is the leading cause of cancer death in both men and women in the United States. Although lung cancer has been treated aggressively by surgery, radiation therapy, and chemotherapy, alone or in combination, survival is still in the 12% to 15% range at 5 years. All curative treatment plans for patients with non-small cell lung cancer include resectional surgery. Despite the dismal outlook there is hope, because improvements in outcome for patients undergoing surgical treatment have been realized. Definite progress has been made in reducing operative mortality and morbidity, helping to increase long-term survival. Advances that have contributed to these successes include improved preoperative evaluation in staging and patient selection criteria, the use of newer techniques such as video-assisted or open limited resections in selected instances, and the use of neoadjuvant therapy. These topics are addressed here, as are techniques for locally advanced tumors and options for palliation. PMID- 9363154 TI - Pulmonary vascular disease. PMID- 9363155 TI - Diagnosis of pulmonary embolism. AB - Present opinion combines the diagnosis and management of deep venous thrombosis and pulmonary embolism. Regarding deep venous thrombosis, clinical assessment based on major and minor diagnostic points in combination with ultrasound of the lower extremities showed useful positive predictive values when the clinical assessments and ultrasound were concordant. Subtle calf asymmetry may call attention to the possibility of thromboembolic disease. The prevalence of acute pulmonary embolism at a general hospital was evaluated. Importantly, the prevalence of unrecognized pulmonary embolism at autopsy has not changed in three decades. Further evaluation was made of the alveolar arterial oxygen difference in the diagnosis of acute pulmonary embolism. As with the partial pressure of oxygen in arterial blood, the alveolar arterial oxygen difference is usually abnormal, but a normal value does not exclude pulmonary embolism. The criteria used for a low probability interpretation of ventilation-perfusion lung scans in the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) were modified. Criteria for a very low probability assessment (< 10% positive predictive value) were also determined. Progress was made with helical CT and contrast-enhanced electron-beam CT, but with present technology their roles are limited. Selective digital subtraction angiography with a flow-directed catheter was useful in some patients. A strategy for diagnosis of thromboembolic disease that uses serial noninvasive leg tests was described. This strategy reduces the number of pulmonary angiograms required. PMID- 9363156 TI - Low molecular weight heparin for the prevention of deep vein thrombosis following orthopedic surgery. AB - Prophylaxis of postoperative thromboembolism is widely used because it has been shown to save lives and money. However, some surgeons are still reluctant to use general prophylaxis in high-risk orthopedic surgery. In total hip and total knee replacement the best method of prophylaxis is currently low molecular weight heparin started preoperatively and continued for 7 to 14 days or until the patient is fully ambulatory. A shorter prophylaxis period failed to be effective in an English study. At present there is an ongoing debate on the length of the period of risk, and whether there is a need for prophylaxis after discharge. Oral anticoagulation has been used for extended prophylaxis, but studies show that anticoagulant levels need to be monitored by repeated measurements by international normalized ratio. An alternative method would be to continue low molecular weight heparin injections for 4 to 5 weeks after surgery. No studies so far have evaluated the efficacy and safety of prolonged prophylaxis with low molecular weight heparin after discharge. PMID- 9363158 TI - Pleural disease. PMID- 9363157 TI - Low molecular weight heparin for the prevention and treatment of venous thromboembolism. AB - Low molecular weight heparin is effective for the prevention and treatment of venous thromboembolism. Low molecular weight heparin has the practical advantage that it does not require anticoagulant monitoring and dose adjustment. The simplified therapy provided by low molecular weight heparin will allow many patients with venous thromboembolism to be cared for in an outpatient setting, with a potential for major savings in health care costs. For preventing venous thromboembolism after hip or knee replacement, and after general abdominal surgery, further cost effectiveness studies are required to determine the ultimate clinical role of low molecular weight heparin. PMID- 9363159 TI - Thoracoscopy: current status. AB - This article presents the current status of thoracoscopy in clinical practice. Aspects of its use in diagnostic, staging, and therapeutic areas are reviewed as regards diseases of the pleura, lung, and mediastinum. Controversies and evolving applications are identified. PMID- 9363160 TI - Parapneumonic effusions and empyema. AB - Thoracic empyema remains a significant medical problem in 1996. Patients in whom empyema develops suffer significant morbidity, frequently require prolonged hospitalizations, and are at an increased risk of death. In this review of parapneumonic effusions and empyema, four topics are discussed: diagnosis of empyema, the organisms responsible for empyema, the methods used for treatment, and the results from animal models of empyema. PMID- 9363161 TI - Pleural tuberculosis: incidence, pathogenesis, diagnosis, and treatment. AB - Recent studies in populations with a high prevalence of tuberculosis and HIV infection report that tuberculous pleurisy occurs in approximately 30% of patients with tuberculosis. However, the fraction of patients with tuberculosis who have tuberculous pleurisy is comparable in HIV-positive and HIV-negative individuals. It appears that tuberculous pleurisy mostly develops in patients with HIV who have CD4 counts above 200/microL. Primary tuberculous pleurisy is thought to occur as a result of a delayed hypersensitivity reaction to mycobacterial antigens. Recent studies highlight the way in which pleural cells become activated and produce cytokines as a response to mycobacteria. Intramacrophage and direct cytotoxic elimination of mycobacteria, granuloma formation, and fibrosis are the main facets of this reaction. Many studies have investigated the usefulness of measuring different parameters in pleural fluid for an early diagnosis of tuberculous pleurisy. It has been shown that the most useful diagnostic tests are the levels of adenosine deaminase and interferon gamma in the pleural fluid. Elevation of either of these compounds in lymphocytic pleural effusions is virtually diagnostic of tuberculous pleurisy. Although theoretically, detection of mycobacterial DNA in the pleural fluid by the polymerase chain reaction would appear to be useful, the usefulness of this test still needs further demonstration. Patients with tuberculous pleurisy must receive antituberculous treatment. The current recommendation for immunocompetent patients is a 6-month regimen of isoniazid and rifampin supplemented in the first 2 months by pyrazinamide. HIV-infected patients should be treated with this same regimen for a longer time period. Serial thoracentesis or corticosteroid treatment are not warranted for the majority of patients. PMID- 9363163 TI - Neoplasms of the lungs. PMID- 9363162 TI - Pleural malignancies. AB - Carcinoma of the lung, metastatic breast carcinoma, and lymphoma are responsible for approximately 75% of all malignant pleural effusions. The presence of malignant cells in the pleural fluid or in the parietal pleura confirms the diagnosis. Recently, several authors have proposed the combination of morphometric procedures and quantitative analysis of nucleolar organizer regions stained by silver nitrate. Videothoracoscopy is recommended for patients suspected of having a malignant pleural effusion in whom the diagnosis is not established after two cytologic studies of the fluid and one needle biopsy. The standard treatment is the intrapleural instillation of a chemical agent to produce a pleurodesis. The recommended sclerosant is talc, a tetracycline derivative, or Corynebacterium parvum where it is available. When a patient is not an ideal candidate for chemical pleurodesis, the options include symptomatic treatment, serial thoracentesis, implantation of a pleuroperitoneal shunt, and pleurectomy. PMID- 9363164 TI - Disorders of pulmonary circulation. PMID- 9363165 TI - Diseases of the pleura. PMID- 9363166 TI - Idiopathic pulmonary fibrosis. AB - Idiopathic pulmonary fibrosis (IPF), or cryptogenic fibrosing alveolitis as it is known in the United Kingdom and Europe, is perhaps one of the most complex and frustrating pulmonary disorders. The cause of this illness is unknown. Treatment often founders in a mire of discontent, dissatisfaction, and failure. In fact, the philosophic homily "If you do not know where you are going, then any road will take you there" in a curious way sums up the trials and tribulations of treating idiopathic interstitial fibrosis. PMID- 9363167 TI - Congenital and pediatric interstitial disease. AB - Congenital and pediatric interstitial lung disease (ILD) is set in the context of the maturing lung and immune system, and thus differs completely from its adult equivalents in presentation, therapy, and outcome. We first establish the background by briefly reviewing normal maturational changes and then describe recent advances in diagnosis. We then highlight three specific topics: drugs and the lung (treatment and iatrogenic ILD); the histiocytic disorders of the lung; and congenital ILD (specifically congenital surfactant protein deficiency). PMID- 9363168 TI - A pathologist's approach to interstitial lung disease. AB - In this review, we outline how each cellular lung component participates in the multiple entities that constitute the pathological spectrum of interstitial lung diseases (ILD). It is our intent to highlight the clinically important differential diagnoses. In addition, we discuss the new concepts of the pathogenesis of ILD as they relate to the morphologic presentation of the lung diseases that target the interstitium. The interaction of inflammatory cells such as macrophages, lymphocytes, and mast cells with lung epithelial cells and fibroblasts results in destruction of the lung parenchyma. These cells participate in the disease entities that comprise ILD. They are sources of growth factors and cytokines that allow intercellular communication to occur. Thus, they play a significant role in the process of lung disease. PMID- 9363169 TI - Immunology of idiopathic pulmonary fibrosis. AB - Idiopathic pulmonary fibrosis (IPF) is an immunomediated disorder characterized by a chronic inflammation of the lower respiratory tract, type I epithelial cell damage, accumulation of connective tissue components, fibroblast proliferation, and deposition of matrix proteins. The past few years have seen remarkable advances in the understanding of the immunopathogenesis of IPF. It is becoming clear that, although normal inflammatory reaction in the lung generally resolves, the rapidity and efficiency with which inflammatory constituents are removed from alveolar airspaces is altered in patients with IPF. The loss of the balance between events that mediate resolution or perpetuation of inflammatory responses sets the stage for severe lung injury, tissue remodelling, and the irreversible development of pulmonary fibrosis. This review outlines the complexity of cellular signalling processes taking place in fibrotic lung, providing a bridge between basic research and clinical relevance in the treatment of these patients. PMID- 9363170 TI - Pulmonary physiology in interstitial lung disease: recent developments in diagnostic and prognostic implications. AB - Pulmonary function changes in interstitial lung disease are characterized by loss of lung volume, increase in ratio of forced expiratory volume in 1 second to forced vital capacity, and decrease in carbon monoxide diffusion capacity. Recent developments in the assessment of respiratory mechanics in infiltrative lung disease have elucidated volume and flow dependence of lung and total respiratory resistance and elastance related to the viscoelastic properties of the respiratory system. A new, simple test of applying negative expiratory pressure at the mouth during tidal expiration can be used to generate expiratory flow volume curves to detect flow limitation in patients with restrictive as well as obstructive disorders. This method is useful in patients who are weak, uncoordinated, or who cough during forced maneuvers. Poor prognostic signs in interstitial lung disease include male gender, paucity of lymphocytes on bronchoalveolar lavage, extensive radiographic infiltration, absence of cellular histologic findings on lung biopsy, presence of right-axis deviation, persistent or progressive decrease in lung volumes, and diffusion capacity of carbon monoxide. PMID- 9363171 TI - Radionuclide imaging in interstitial lung disease. AB - The use of radionuclides to evaluate interstitial lung disease (ILD) has a long history. In the mid- and late 1970 s, it was appreciated that gallium uptake was seen in the lungs of patients with sarcoidosis or idiopathic pulmonary fibrosis. In both of these conditions, the amount of uptake seemed to correlate with other measures of inflammation in the lung. Gallium uptake was shown to predict response to therapy and persistent disease. However, several limitations to gallium scanning soon became apparent. The procedure is costly, it requires 48 to 72 hours for proper interpretation, and the uptake reverses quickly during corticosteroid therapy. The use of aerosol scanning with 99mTc-pentetic acid (DTPA) has also been shown to be useful in ILD. The clearance of 99mTc-DTPA aerosol is markedly increased in both sarcoidosis and other inflammatory lung diseases. However, the limitations of 99mTc-DTPA include the fact that cigarette smoking will also cause increased clearance. Therefore, the value of 99mTc-DTPA scanning value seems to be limited to nonsmokers. Several recent papers published on these and other techniques are reviewed here. PMID- 9363172 TI - The pulmonary infiltration with eosinophilia syndrome. AB - The term eosinophilia denotes an absolute eosinophil count above 500 cells/microL. Eosinophilia has been noted in various inflammatory disorders: skin conditions (eczema, dermatitis, generalized drug reactions), malignancies (Hodgkin's disease and lung cancer), chronic granulomatous disorders (tuberculosis, sarcoidosis), fungal diseases (coccidioidomycosis, aspergillosis), drug- and chemical--related conditions, and idiopathic pulmonary infiltrate and eosinophilia syndromes. The incidence of pulmonary infiltration with eosinophilia is on the rise. Idiopathic pulmonary eosinophilia should be distinguished from the eosinophilic myeloproliferative syndrome. The diagnosis can usually be secured with the help of a good history and physical examination enhanced by simple laboratory tests on blood and sputum and a chest radiogram. The therapy is then directed to correct the initial injury. PMID- 9363173 TI - Effects of radiation on the lung. AB - Since the beginning of the twentieth century, radiation has been employed as a tool to cure or palliate malignancy. Unfortunately, soon after its discovery, the harmful effects of radiation were recognized as well. As our understanding of the physiologic responses to radiation increases, we can refine the routes of delivery and dosages of radiation administered. The use of three-dimensional treatment planning and the manipulation of the biochemical response with drugs and synthesized cytokines offers promise in curtailing the undesirable effects of irradiation. Side effects will be minimized and benefits maximized with further technologic developments that will more accurately control the delivery of and response to radiation. PMID- 9363174 TI - Drug-induced interstitial lung disease. AB - Drugs can have multiple different adverse effects on the lungs, airways, pleura, mediastinum, and the interstitium. Their appearance can mimic other interstitial lung diseases and, for the most part, drug-induced interstitial lung disease is a condition of exclusion rather than a specific entity that can be diagnosed with imaging studies or histology. It is important to be aware of all the potential adverse effects of drugs on the lung in order to recognize the condition and to discontinue the drug as soon as possible, as death will result in many of the situations discussed here if appropriate measures are not taken. PMID- 9363175 TI - Uncommon causes of occupational interstitial lung diseases. AB - Uncommon causes of occupational interstitial lung disease, or pneumoconiosis, are being increasingly recognized and diagnosed. The fibrogenic potential of numerous types of respirable inorganic particles remains poorly understood but is significantly determined by lung deposition and clearance, the agent's size and solubility, host susceptibility, and other factors. Microanalytic techniques have improved the identification of uncommon or unusual biopersistent particles or elements in fibrotic lung tissue. Recent findings in workers exposed to manmade vitreous fibers, silicon carbide, talc, titanium, cerium, and polyvinyl chloride provide new clinical insights into not only their specific fibrogenic capabilities but also in the broader appreciation that many cases of unexplained interstitial lung disease may be caused by occupational exposures to one or more uncommon airborne substances. PMID- 9363176 TI - Noninfectious pulmonary complications after organ transplantation. AB - Organ transplantation is a successful and recognized option for patients with end stage pulmonary, cardiac, hepatic, renal, and hematologic disease. As with any new technology, however, a set of complications has developed in the form of lung injury after transplantation as a result of ischemic, chemotherapeutic, radiation induced, and immunologic damage to the lungs. Interstitial changes soon after transplantation are typically due to pulmonary edema, the adult respiratory distress syndrome, and reperfusion injury or allograft rejection (in the case of lung transplantation). Late pulmonary injury presents as obliterative bronchiolitis and lymphoproliferative disease. Bone marrow transplant recipients are unique because they develop the idiopathic pneumonia syndrome, diffuse alveolar hemorrhage, pulmonary venoocclusive disease, and graft-versus-host disease. New insights about these interstitial syndromes are the subject of this review. PMID- 9363177 TI - Bronchiolitis obliterans with organizing pneumonia. AB - In 1955, Epler and Colby first described idiopathic bronchiolitis obliterans with organizing pneumonia. Davison and colleagues termed the entity cryptogenic organizing pneumonia. Clinically, the disease resembles a flu-like syndrome of acute or subacute onset. Other features include crackles, patchy infiltrates on chest radiograph, restrictive function, and decrease in diffusing capacity. Most cases of idiopathic bronchiolitis obliterans with organizing pneumonia (BOOP) respond dramatically to corticosteroids. However, some patients deteriorate rapidly. Differences between idiopathic or secondary BOOP and other interstitial lung diseases are vast. CT findings and bronchoalveolar lavage fluid lymphocytosis are helpful in differentiating BOOP from idiopathic pulmonary fibrosis. PMID- 9363178 TI - Pulmonary involvement in primary Sjogren's syndrome. AB - Interstitial pulmonary fibrosis and tracheobronchial sicca are the most common presentation of pulmonary involvement in primary Sjogren's syndrome. There is wide spectrum of less common manifestations, including pulmonary arterial hypertension, pseudolymphoma, pulmonary lymphoma, lymphocytic interstitial pneumonitis, amyloidosis, and pleurisy. Pulmonary function test abnormalities showing a restrictive pattern and cellular abnormalities in bronchoalveolar lavage fluid for prevalent in patients without respiratory complaints and normal chest radiographs. Long-term prospective controlled studies are needed to determine the clinical course and significance of these findings. PMID- 9363180 TI - Interstitial lung disease. PMID- 9363179 TI - Update on lymphoid interstitial pneumonitis. AB - Lymphoid interstitial pneumonitis (LIP) involves a clinicopathologic pattern of pulmonary disease characterized by diffuse interstitial reactive lymphoid infiltrates. In adults, it occurs most commonly in autoimmune diseases, such as Sjogren's syndrome (0.9% of these patients) and primary biliary cirrhosis, whereas in children it is usually seen in HIV infection. Dysproteinemias (hyper- and hypogammaglobulinemia) are found in more than 60% of patients. Children can show CD8-lymphocytosis in bronchoalveolar lavage fluid, lung tissue, peripheral blood, and salivary gland, associated with HLA-DR5 haplotype. Radiographically, most patients with LIP have reticulonodular infiltrates, with or without patchy areas of consolidation. CT scans can show both small nodular and ground glass patterns, patterns that are diagnostically nonspecific. Reduced lung volumes and diffusing capacities are consistent and sensitive indicators of disease in LIP. In an experimental model, diffusing capacity was the single most sensitive functional index of disease progression. Microscopically, LIP is part of a spectrum of pulmonary lymphoid proliferations, ranging from follicular bronchitis bronchiolitis and pulmonary lymphoid hyperplasia (the latter in AIDS patients), proliferations largely limited to airways, to low-grade malignant lymphoma. These patterns may be difficult to differentiate from each other. It appears that LIP sometimes evolves to lymphoma; the frequency of this evolution is probably low but is difficult to assess because low-grade lymphomas may mimic LIP. A relatively high frequency of LIP patients have Epstein-Barr virus DNA in their lungs but not all patients with LIP show this finding, suggesting other possible etiologies. PMID- 9363181 TI - Cystic fibrosis. PMID- 9363182 TI - Antibiotic use in cystic fibrosis. AB - Antibiotic administration is the mainstay of therapy for pulmonary disease in patients with cystic fibrosis (CF). The progressive nature of the pulmonary disease in CF shortens survival. New and potent antibiotics, more aggressive antibiotic therapy, and multiple routes of administration have contributed to improved survival among CF patients. Pseudomonas aeruginosa is the predominant bacterial pathogen in the lower airways of CF patients. Most of the efforts in treating the chronic pulmonary infection are directed toward this organism. Aerosol aminoglycoside delivery provides a safe and effective alternative method to parenteral administration for treating patients who require chronic antibiotic therapy. This article reviews strategies for choosing antibiotics and current opinions regarding antibiotic therapy for patients with CF. PMID- 9363183 TI - Airway clearance techniques in the treatment of cystic fibrosis. AB - Airway clearance is a major component of the management of cystic fibrosis. In North America, the airway clearance technique of choice has been physiotherapy using postural drainage combined with chest percussion, deep breathing and vibration. The disadvantages of this technique, the introduction of newer airway clearance techniques, and a greater emphasis on exercise has sparked a growing trend to prescribing individualized programs combining exercise with strategies adapted to the needs of each patient. PMID- 9363186 TI - Pulmonary function during pregnancy in cystic fibrosis: implications for counseling. AB - The median survival for patients with cystic fibrosis (CF) has increased from 1 year in the 1940s to nearly 30 years today, and one third of the CF population is over the age of 16 years. As women with CF attain adulthood they are necessarily confronted with issues related to their reproductive potential. In the past, pregnancy in these woman has been considered risky. Recent data suggest that pregnancy may be a viable option for patients with mild disease. The purpose of a study from the Cystic Fibrosis Foundation National Patient Registry is to identify specific indices for quantitating risks related to pregnancy for women with CF so that their physicians, with these data in hand, will be better able to counsel them. PMID- 9363185 TI - The interrelationship of nutrition and pulmonary function in patients with cystic fibrosis. AB - This paper reviews recent publications on the interrelationship of nutrition and pulmonary function in patients with cystic fibrosis. It is unclear whether low weight is a cause or an effect of declining pulmonary status in patients with cystic fibrosis. Epidemiologic studies suggest that low weight may be an independent predictor of mortality. Elevations in energy expenditure are not seen in presymptomatic infants. The elevations in energy expenditure seen in those with lung disease are not totally explained by increased oxygen cost of breathing and can be decreased by improving lung function. Although circulating levels of natural antioxidants and inflammation-modulating nutrients are low in patients with cystic fibrosis and can be increased with supplements, there are no recent data on their clinical effects. Nutritional intervention for patients with chronic illness needs to take into account psychosocial and adherence factors as well as nutritional prescriptions. Pancreatic enzyme supplementation should be limited to no greater than 2500 lipase units per kilogram per meal to decrease the risk of developing dose-related fibrosing colonopathy. PMID- 9363184 TI - Treatment of airway inflammation in cystic fibrosis. AB - Airway inflammation is now recognized as a major factor in the pathogenesis of cystic fibrosis (CF) lung disease. Therapies aimed at decreasing the inflammatory response represent a new strategy for treatment, and attention has focused primarily on the therapeutic potential of corticosteroids and nonsteroidal anti inflammatory drugs (NSAIDs). Alternate-day prednisone (1 mg/kg) may be beneficial; however, unacceptable adverse effects limit long-term use. Inhaled corticosteroids are under investigation as a safer alternative. High-dose ibuprofen (approximately 20-30 mg/kg twice daily) has been shown to decrease the progression of CF lung disease, particularly in children with mild lung disease, and it is without significant toxicity. Other NSAIDs (piroxicam) are under consideration, as well as pentoxifylline and fish oil. The rationale for all of these agents lies in their potential to decrease neutrophil influx into the lung. Because of the large burden and deleterious effects of uninhibited neutrophil elastase and oxidants in the CF airway, antiproteases and antioxidants are also being studied. To optimize anti-inflammatory therapy, it is necessary to understand the mechanism of action of these agents in the CF lung, to determine which of these agents would provide the most benefit to patients with CF, and to determine which therapies should be initiated at what age or stage of lung disease. It is hoped that adding anti-inflammatory therapy to an already comprehensive treatment program will decrease morbidity and improve the quality of life for patients with CF. PMID- 9363187 TI - Is gene therapy in cystic fibrosis a realistic expectation? AB - To date there are 11 human protocols either ongoing or approved for gene therapy for cystic fibrosis (CF) in the United States. There are also two protocols in the United Kingdom and one in France. Of these, results have been published in four. The protocols vary in the cells targeted, the vectors used, and the frequency of administration, but despite these differences all have contributed toward answering the key questions that will determine the future of gene therapy for CF: the questions of efficacy and safety. These studies have demonstrated that it is feasible to transfer the normal human CF transmembrane conductance regulator complementary DNA to the respiratory epithelium and that this will lead to production of normal CF transmembrane conductance regulator protein and in some cases to a physiologic response. The most frequently used vector is the adenovirus. Obstacles to be overcome with this system include the need for improved and prolonged expression, efficacy on repeat administration, and decreased inflammation. Recent work on the immune response to adenoviral vectors may help achieve these goals. The cationic lipid method of gene delivery is less likely than adenovirus to cause inflammation, at least in the nose, but improved efficacy of gene transfer is necessary as well as improved complex stability. Furthermore, this system has yet to be tested in the lungs of individuals with CF. Finally, the adeno-associated virus, the other vector approved for human gene therapy studies in CF, has shown some promise in preclinical studies but remains to be tested in humans. The results of these studies give some cause for guarded optimism, but point out a number of problems that must be overcome before gene therapy for CF delivers on the promise of a safe effective treatment for this condition. PMID- 9363188 TI - Reticular modulation of breathing during sleep and anesthesia. AB - Although sleep and anesthesia are distinctly different states of consciousness, they manifest some common physiologic traits, including respiratory depression. Support is lacking for the concept of any unitary mechanism causing the loss of wakefulness and the respiratory depression associated with sleep or anesthesia. A recently emerging view is that brain mechanisms, which have evolved to generate naturally occurring states of consciousness, are preferentially involved in generating traits characterizing some anesthetic states. The brain stem reticular formation mediates four functions of direct relevance for sleep and anesthesia. Recent work is selectively reviewed showing that brain stem cholinergic and monoaminergic neurons alter breathing while modulating behavioral states, muscle tone, cardiopulmonary control, and pain sensation. The ability of these four functions to influence breathing also makes clear their potential to serve as confounding variables in experimental models from which they are ignored or systematically excluded. PMID- 9363189 TI - Perspectives in narcolepsy research and therapy. AB - Narcolepsy with associated cataplexy is a disabling sleep disorder that affects 0.05% of the general population. Whereas narcolepsy-cataplexy is largely considered as etiologically homogeneous, hypersomnias without cataplexy represent a very heterogeneous group of clinical entities that must be thoroughly explored before final diagnosis of narcolepsy is given. A typical treatment for narcolepsy cataplexy associates amphetamine-like stimulants for sleepiness and antidepressant therapy for abnormal rapid eye movement sleep (cataplexy, sleep paralysis, and hypnagogic hallucinations). This treatment is purely symptomatic and involves activation of central dopaminergic and adrenergic activity respectively. Genetic research indicates a role for the immune system rather than abnormalities in monoaminergic or cholinergic systems as the primary cause for narcolepsy. Human narcolepsy is tightly associated with HLA-DQB1*0602; canine narcolepsy is linked with a DNA segment with high homology with the human immunoglobulin mu-switch segment, and the onset of canine narcolepsy is associated with increased microglial expression of major histocompatibility complex DQ and DR molecules. Taken together with the lack of direct evidence for an autoimmune process in narcolepsy, these results may suggest the existence of novel neuroimmune interactions in narcolepsy and open new perspectives in the treatment of this disabling disorder. PMID- 9363190 TI - Sleepiness and human behavior. AB - The 24-hour properties of sleepiness affect behavior by reducing performance and increasing the likelihood of accidents. This is important to pulmonary physicians who diagnose and treat sleep apnea, because diagnoses of sleep apnea and narcolepsy are associated with as much as a sevenfold increase in the risk of having a motor vehicle accident. Human abilities throughout the 24-hour day have noticeable ups and downs and are probably causally linked to the same control mechanisms that produce the early morning and midafternoon peaks in the tendency to fall asleep. An important characteristic of this pattern is that increased sleep tendency, regardless of how the increase comes about, does not alter the timing of the peaks. In California, and perhaps other states, current laws can be interpreted as requiring clinicians to report all patients with conditions such as sleep apnea and narcolepsy to the county health officer. Although this policy is at variance with recommendations of the American Thoracic Society, attorneys have advised that, in California, a policy of uniformly reporting all patients with disorders of excessive somnolence is proper. Because ignorance of the law is not a valid defense, it is important for physicians to be aware of all state laws relevant to their patients who may be impaired by sleepiness. PMID- 9363191 TI - Developmental aspects of sleep and breathing. AB - The developmental aspects of sleep and breathing are rarely treated as one subject. This report attempts to link the fields of sleep research and developmental pulmonology in a comprehensive description of development and control of sleep and breathing from gestation to adulthood. Unfortunately, much of the investigation in this area is basic physiology and was done some time ago. Although this subject matter need not be updated, some of these references are older; however, this may be new information for the pulmonologist. The second part of this report details the pathophysiologic mechanisms behind the development of sleep-disordered breathing in children and adults. In fact, developmental abnormalities that occur in childhood may recrudesce in adulthood. We conclude with a discussion of the familial and genetic aspects of sleep disordered breathing and consider the place of sudden infant death syndrome in the spectrum of these disorders. PMID- 9363192 TI - Sleep-wake cycles and the management of respiratory failure. AB - Sleep is characterized by many changes in the respiratory system, including a reduction in respiratory motor output associated with the loss of wakefulness, increased upper airway resistance, and blunted protective reflexes (such as load compensation), that result in reduced alveolar ventilation. The development of carbon dioxide retention appears to be linked to the exaggeration of sleep related changes on ventilation by coexistent respiratory system disorders. Sleep disordered breathing is becoming increasingly recognized in subjects with neuromuscular diseases, who may be prone to nocturnal respiratory events due to diaphragm and bulbar muscle weakness, abnormal central respiratory control, obesity, and sleep position restrictions. Nocturnal gas exchange deterioration may occur in patients with chronic obstructive pulmonary disease, particularly during rapid eye movement sleep when activity of the respiratory muscles other than the diaphragm is inhibited. Concurrent obstructive sleep apnea syndrome may further compromise nocturnal ventilation, thereby contributing to the development of acute or chronic respiratory failure. The use of noninvasive nocturnal ventilation at night has resulted in significant improvements in symptoms of hypoventilation and daytime carbon dioxide retention in various clinical settings, yet important questions remain about implementation of this modality. PMID- 9363193 TI - Sleep disorders and outpatient treatment of patients with pulmonary disease. AB - Patients with chronic obstructive pulmonary disease, kyphoscoliosis, and neuromuscular disorders frequently desaturate in rapid eye movement sleep. This can lead to polycythemia, pulmonary hypertension, and respiratory failure. In addition, these patients as well as those with asthma may have unsuspected coexistent obstructive sleep apnea. The detection of hypoventilation, oxygen desaturation, and obstructive sleep apnea may lead to more effective treatment of these patients. PMID- 9363194 TI - Cystic fibrosis. PMID- 9363195 TI - Sleep and respiratory neurobiology. PMID- 9363196 TI - Cell adhesion, cell adhesion molecules and their functional role in the human endometrium. AB - In summary, cadherins are important determinants of tissue morphology. They play a major role in the maintenance of intercellular junctions in normal epithelial cells in most organs. Cadherin expression is found to be perturbed in human invasive carcinoma. Cadherins are probably crucial for many other morphogenetic processes which involve selective cell adhesion or detachment. Expression of integrins allows binding of endometrial cells to various ligands (fibronectin, laminin, collagens) and hence adds to the preservation of the architectural integrity of endometrium. Regulation of adhesion-molecule expression probably contributes to the invasive behavior of cytotrophoblast, both in physiological and pathophysiological conditions. The integrin expression by the endometrium seems to be a dynamic process, many details of which still remain to be elucidated. PMID- 9363197 TI - A meta-analysis of perinatal complications of maternal diabetes. Can they be prevented? PMID- 9363199 TI - Differential effects of plasma from normal and ectopic gestation on lymphocyte proliferation. AB - This study investigated immunoregulatory differences as a result of anatomical changes in the fetomaternal interface. Thirty-one female subjects were recruited from a military tertiary-care facility. Ten subjects were non-pregnant while 21 were pregnant (nine normal and 12 ectopic gestations). Immune tests included one way mixed lymphocyte cultures with and without maternal plasma, phytohemagglutinin stimulation and lymphocyte phenotypes. Basic statistics and a one-way ANOVA using Tuckey's HSD model were employed. Autologous plasma significantly enhanced the allogeneic responses of first-trimester pregnant females with normal gestations to spouses as well as to control male lymphocytes. This enhancement was not observed in either ectopically-pregnant or non-pregnant subjects. Mitogen stimulation and lymphocyte populations were similar in all three groups. The first trimester of normal pregnancy is characterized by the presence of soluble intrauterine pregnancy-specific lymphocyte-enhancing factors. Ectopic gestation lacks this phenomenon. PMID- 9363198 TI - Localization of leukemia inhibitory factor in human endometrium during the menstrual cycle. AB - Leukemia inhibitory factor (LIF) has been shown to be imperative for the implantation of mouse blastocysts. The objective of this study was to examine the pattern of LIF protein in the human endometrium during the menstrual cycle. A low level of LIF was detected in endometrial glands during the proliferative phase. During the luteal phase, LIF staining in the glands appeared stronger in the mid- and late luteal phase than immediately after ovulation. However, a low level of LIF was detected in the stromal cells during the early and midproliferative phase, while only a minimal level was observed during the late proliferative and luteal phases. PMID- 9363201 TI - Comparison of production of choriogonadotropin inhibitory protein, prolactin and insulin-like growth factor binding protein-1 by human decidua in vitro. AB - We have previously demonstrated that human decidua produces a protein (decidual choriogonadotropin inhibitory protein, DCIP) that inhibits human chorionic gonadotropin (hCG) secretion from primary trophoblasts and JEG-3 choriocarcinoma cells. The present study was undertaken to examine the relationship of DCIP production to that of cell protein, prolactin (PRL) and insulin-like growth factor binding protein-1 (IGFBP-1). Term decidual cells, isolated from placental membranes by enzyme digestion and density gradient centrifugation, were incubated for 12 days in serum-free CMRL-1066 medium which was changed daily. At the end of each experiment the DCIP in the decidual culture medium was measured by bioassay: the percentage reduction, from control, of hCG production by JEG-3 cells exposed to 30% DCIP-containing decidual culture medium. Prolactin, IGFBP-1 and hCG were measured by radioimmunoassay. The DCIP activity was maximal during the first 3 days in culture. The bioactivity of decidual culture medium collected after the 5th day of culture gradually decreased and medium obtained from the final day of culture actually stimulated hCG secretion in the bioassay. Decidual cell protein gradually declined from 100% on day 1 to 56% on the last day of culture. The concentrations of protein, PRL and IGFBP-1 in the decidual culture medium gradually decreased during the first 4-6 days, followed by a rise. In contrast, glucose increased with time in culture. Production of PRL, IGFBP-1 and decidual culture medium protein exhibited a significant quadratic effect over the 12 days in culture. There was a negative relationship between decidual cell protein and glucose (r = -0.95) and a positive correlation between cell protein and protein in the decidual culture medium (r = 0.58). The DCIP activity was related to cell protein (r = 0.39), protein concentration in decidual culture medium (r = 0.36), and inversely related to the glucose level (r = -0.41). There was no relationship between DCIP activity and PRL or IGFBP-1. These results indicate that maximal DCIP production occurs during the first several days in short-term culture of decidual cells and is related to decidual-cell viability. As decidual-cell viability decreases, there is less glucose consumption in the decidual culture medium and the higher glucose levels may be responsible for the stimulatory effect of medium collected at the end of the study on JEG-3 hCG secretion. PMID- 9363200 TI - Comparative responsiveness to prolonged hyperinsulinemia between adipose-tissue and mammary-gland lipoprotein lipase activities in pregnant rats. AB - The present study was addressed to determining the comparative responsiveness of lipoprotein lipase (LPL) activity, in white adipose tissue and mammary gland, to a prolonged hyperinsulinemic stimulus, in pregnant and virgin rats. Pregnant rats at the 17th day of gestation and virgin animals were subjected, under conscious and unrestrained conditions, to a continuous infusion with either 50% glucose or double-distilled water (controls) (35 ml/day) for 72 h through a catheter in the jugular vein. The basal plasma-glucose levels were lower in pregnant than in virgin rats. After the glucose infusion plasma-glucose levels remained unchanged but plasma-insulin levels were much higher, and this effect was greater in pregnant than in virgin rats. Whereas LPL activity in white adipose tissue in the controls was lower in pregnant than in virgin rats, in rats receiving the glucose infusion it increased more in pregnant than in virgin rats. However, LPL activity in the mammary gland was already higher in control pregnant rats than in virgin controls and the glucose infusion caused a similar increase in both groups. Although there was a linear correlation when individual values, from all the studied rats, for LPL activity in both tissues were plotted against plasma insulin levels, the correlation coefficient was much higher for mammary-gland LPL activity than for adipose-tissue LPL activity. Plasma-triglyceride levels were higher in pregnant than in virgin rats. The glucose infusion did not modify this parameter, probably because of the changes in LPL activity in other tissues which are known to occur in the opposite direction to those observed in this study for adipose tissue and mammary gland. The present results support the notion that the insulin resistant condition which normally occurs during late gestation is responsible for the decreased LPL activity in adipose tissue, but that the mammary gland remains sensitive to insulin and so maternal hyperinsulinemia would contribute to the induction of LPL activity in this organ prior to parturition. PMID- 9363202 TI - Current progress in early pregnancy investigation. PMID- 9363203 TI - Pregnancy and antiphospholipid syndrome. A report and relevant abstracts from the 4th International Conference on Systemic Lupus Erythematosis, Jerusalem, March 1995. PMID- 9363204 TI - Reflections on early pregnancy: organizing chaos or organized chaos? PMID- 9363205 TI - Spontaneous and habitual abortion--a pathologist's point of view. PMID- 9363206 TI - Pitfalls in interpreting therapy for early pregnancy. PMID- 9363207 TI - Altered expression of the tumor suppressor/oncoprotein p53 in SV40 Tag transformed human placental trophoblast and malignant trophoblast cell lines. AB - The expression of the tumor suppressor/oncoprotein p53 has been investigated in normal human placental villous trophoblast, in vitro propagated invasive extravillous trophoblast, SV40 tumor antigen (Tag)-immortalized extravillous trophoblast, human cytomegalovirus (hCMV)-infected syncytiotrophoblast and malignant trophoblast (choriocarcinoma) cell lines (JAR, JEG-3 and BeWo) using quantitative enzyme-linked immunosorbent assay (ELISA) and Western immunoblot methods using monoclonal antibodies specific for wild-type and mutant p53. The normal villous and extravillous trophoblast cells expressed low levels of the wild-type p53 protein, whereas normal terminally differentiated multinucleated syncytiotrophoblast cells, as well as hCMV-infected syncytiotrophoblast, showed a higher expression of the wild-type p53 protein. SV40 Tag-immortalized invasive trophoblast cells also showed a high expression of the wild-type p53 protein which remained complexed with the Tag protein. All the choriocarcinoma cell lines over expressed the mutant form of the p53 protein. The increased expression of p53 protein in the SV40 Tag-immortalized invasive trophoblast and choriocarcinoma cells paralleled with increased expression of the mouse double minute 2 (mdm2) oncogenic protein. Transforming growth factor (TGF)-beta inhibited proliferation of normal extravillous trophoblast cells. The antiproliferative effects of TGF beta were reduced in SV40 Tag-immortalized cells and non-detectable in choriocarcinoma cell lines JAR, BeWo and JEG-3. The inactivation of p53 owing to complexing with Tag in the immortalized premalignant trophoblast and p53 mutation in the malignant trophoblast may be responsible for their aberrant proliferation and refractoriness to antiproliferative effects of TGF-beta observed in these cells as compared to the normal trophoblast. These results may suggest the role of p53 protein in trophoblast differentiation, transformation and tumorigenesis. PMID- 9363208 TI - Relationship of estradiol and progesterone levels to uterine blood flow during early pregnancy. AB - The purpose of this study was to examine the relationship of uterine blood flow to serum estradiol and progesterone during early pregnancy. Recumbent uterine artery average velocity, diameter, blood flow volume and uterine and spiral artery resistance were measured using vaginal Doppler ultrasound 118 times in 43 patients during gestational (postmenstrual) weeks 5 to 16. Relationships to serum progesterone and estrogen were analyzed before and after week 10, when intervillous circulation begins, by multiple linear regression analysis and analysis of covariance (ANCOVA) to correct for the effect of gestational age. After correction for gestational age, estradiol was negatively related to uterine artery flow volume (p < 0.05), diameter (p < 0.05), pulsatility index (p < 0.05) and resistance index (p < 0.01) for weeks 5-16 and to diameter (p < 0.05) after week 9. Progesterone was positively related to volume (p < 0.05) and velocity (p < 0.01) for weeks 5-16 and to volume (p < 0.05) for weeks 5 to 9. Spiral artery indices of resistance were unrelated to hormone levels. These results indicate that before the 10th gestational week, uterine blood flow volume is related to progesterone, but not estradiol levels, and suggest that high estradiol levels during and after the 10th week may be associated with decreased uterine blood flow volume. PMID- 9363209 TI - Advances in the understanding of diabetic embryopathy: signal transduction. AB - Evidence supports the theory that in diabetic pregnant women, it is the degree of metabolic imbalance present during the crucial time of organogenesis that determines the organogenetic congenital defects. The precise mechanism responsible for abnormal fetal organogenesis is unclear, but fuels such as sugars (glucose, galactose, mannose), ketones, fuel-related principles such as somatomedin inhibitors, insulin, trace elements and, lately, myoinositol, arachidonic acid and free oxygen radicals have all been implicated. The plasma membrane lipids, in addition to serving as barriers that separate intracellular from extracellular fluid, are the actual sources of signal molecules. In one case, the signal molecule (diphosphoinositol) is derived from a variant of a common membrane lipid. This is similar to the situation in which a hormone, or similar extracellular messenger, binds to its membrane receptor and activates an enzyme that hydrolyzes plasma-membrane phospholipids to liberate arachidonic acid, which is a precursor of signal molecules, including the prostaglandins. Disruption of these delicate processes by various agents (metabolites) could result in deficiencies in phosphoinositol turnover or arachidonic acid metabolism, thus leading to congenital anomalies. PMID- 9363210 TI - Prostaglandin metabolism in the yolk sacs of normal and diabetic pregnancies. AB - The malformations commonly found in fetuses of diabetic mothers occur before the 7th week of pregnancy, when fetal nutritional needs are met largely by the yolk sac. The diabetic milieu has been hypothesized to cause a disruption in the metabolism of arachidonic acid and phosphatidylinositol turnover, leading to a reduction in prostaglandin levels. In this study we evaluated how the diabetic milieu affects yolk-sac prostaglandin levels. We used ultrasound to characterize and guide aspiration of the yolk sacs of eight diabetic and 12 healthy women prior to elective abortion. In addition, we studied the yolk sacs of two healthy women in whom pregnancy termination was carried out by hysterectomy. All fetuses were between 8 and 10 weeks gestational age at the time of pregnancy termination. The yolk-sac prostaglandin E2 levels were measured using radioimmunoassay. We found that the yolk-sac diameters of diabetic women were 1.2 mm larger than those of normal women. Furthermore, the mean prostaglandin E2 level in healthy women was 3605 pg/ml, whereas prostaglandin was undetected in all the yolk sacs of diabetic women (p < 0.001). While this study suggests that defective yolk-sac metabolism of prostaglandins is one of the mechanisms responsible for diabetic embryopathy, further research is necessary to place yolk-sac enlargement and the role of prostaglandins in perspective. PMID- 9363212 TI - Current progress in early pregnancy investigation. PMID- 9363211 TI - Developing biotechnological and pharmacotherapeutic advances in early pregnancy. PMID- 9363213 TI - Sonography in the first trimester screening of trisomy 21 and other fetal aneuploidies. PMID- 9363214 TI - Ontogeny of glucose transport systems in the placenta and its progenitor tissues. AB - Glucose is the primary substrate for placental and fetal metabolism, however, it can be synthesized in the fetus from placentally transferred substrates at best in minimal amounts. Therefore, the growing glucose requirements of the fetus throughout pregnancy must be met by increases in placental transport capacity. Results reviewed here indicate that the GLUT1 isoform represents the major glucose transporter species in human, and very likely in all mammalian, placentae as well as in fetal membranes and its progenitor tissues. This isoform is abundant in all placental cell populations including those fronting to the maternal and fetal circulation independent of anatomical differences of the placentae. The developmental changes of GLUT1 mRNA are controversial but the amount of GLUT1 protein tends to increase during pregnancy until term. GLUT1 seems also to play the predominant role in glucose uptake in the oocytes and preimplantation cleavage stages of rodents. Its mRNA and protein levels increased during preimplantation development. Furthermore, GLUT1 was demonstrated in the trophectoderm of mouse blastocysts, the direct progenitor tissue of the placenta. GLUT2 is generally not detected in the chorioallantoic placenta. If present at all, GLUT3 seems to be the only candidate for complementing GLUT1 in placental glucose uptake and transport function. The absence of the insulin-sensitive GLUT4 in the placenta is in line with the current consensus of insulin-independent glucose transport. The fructose transporter GLUT5 was only detected in human spermatozoa. All data available at present underline the paramount importance of GLUT1 for glucose transfer in the developing fetoplacental unit. PMID- 9363215 TI - Evidence favoring human chorionic gonadotropin as the physiological 'rescuer' of the corpus luteum during early pregnancy. PMID- 9363216 TI - Elevation of cyclic AMP levels in mouse embryonic stem cells by insulin related peptides. AB - The preimplantation mammalian embryo has been shown to respond to exogenous insulin-like growth factors and insulin itself, however, the most quantitatively important source of these peptides and the receptors through which they exert their effects are unclear. Whilst the type 1 insulin-like growth factor (IGF) receptor is believed to act primarily through tyrosine phosphorylation of the substrate protein alpha IRS-1, evidence for a signalling role for the type 2 receptor is disputed, some evidence pointing to mediation through G protein dependent calcium ion flux. We have examined the response of murine embryonic stem cells, as a model for the cells of the preimplantation embryo, to IGF-I, IGF II, insulin and analogs of IGF-II: R6 IGF-II and des (1-6) IGF-II. In response to all of these peptides, except R6 IGF-II, elevation of intracellular cyclic AMP occurs. As R6 IGF-II binds with higher affinity to the type 2 receptor than canonical IGF-II or IGF-I, and insulin fails to interact, this suggests that the elevation of cyclic AMP in response to the other insulin related peptides (IRPs) is not through the type 2 receptor. We conclude that either the type 1 receptor has a previously uncharacterized direct or indirect effect on intracellular cyclic AMP levels, or that there is a further, as yet uncharacterized, receptor active in embryonic stem cells. PMID- 9363217 TI - Microalbuminuria in early pregnancy in normal and high-risk patients. AB - The albumin excretion rate (AER) is elevated in normal pregnant women in the third trimester of pregnancy, compared to the second and first trimesters, and to the non-pregnant state. The effect of early pregnancy on AER values was tested in normal and high-risk pregnant patients using radioimmunoassay. All pregnant patients demonstrated significantly higher AER values as compared to non-pregnant women, and the results were in correlation with higher urinary creatinine clearance values. The appearance of microalbuminuria in the first trimester can indicate underlying renal damage in patients at high risk of hypertensive complications. PMID- 9363218 TI - Variations in human placental 11 beta-dehydrogenase and 11-oxoreductase activities of 11 beta-hydroxysteroid dehydrogenase enzyme during pregnancy. AB - Human placental 11 beta-hydroxysteroid dehydrogenase enzyme has an important role in controlling glucocorticoids reaching the fetus. Excess glucocorticoids impair fetal growth. Recent investigations show that the placenta is rich in NAD- and NADP-dependent 11 beta-hydroxysteroid dehydrogenase activity. Elucidation of the activities of both these isoforms is necessary to understand placental glucocorticoid metabolism. Hence we determined both NAD- and NADP-dependent 11 beta-hydroxysteroid dehydrogenase activities throughout pregnancy. 11 beta dehydrogenase (oxidative) and 11-oxoreductase (reductive) activities of 11 beta hydroxysteroid dehydrogenase were determined in 16 first-trimester (9-12 weeks) and 14 second-trimester (13-22 weeks) and 17 term (38-42 weeks) placentae. Both NAD- and NADP-dependent activities increased with pregnancy. The second-trimester NAD-dependent activity was higher than the first-trimester activity (p = 0.02). At term this activity was higher than during the second (p = 0.05) and first (p = 0.0002) trimesters. A similar increase was obtained with NADP isoform except that the difference between first and second trimesters was not significantly different at p = 0.05. The NADH-dependent 11-oxoreductase activity was also detected throughout the pregnancy. However, the activity at term was significantly higher than during the second (p = 0.005) and first (p = 0.001) trimesters. This increase may result in a concomitant increase of cortisol reaching fetus, thus helping fetal lung maturation. PMID- 9363219 TI - Current progress in early pregnancy investigation. PMID- 9363220 TI - Implantation and early pregnancy loss. A report and relevant abstracts from a conference held in Paris, February 1996. PMID- 9363221 TI - Management of threatened abortion. AB - Threatened abortion is associated with bleeding and/or uterine cramping while the cervix is closed. This stage of abortion may progress to spontaneous incomplete or complete abortion. While this event may be considered a part of the quality control process in human reproduction, it is important to know the possible etiologies and when therapy might prevent pregnancy loss. The World Health Organization estimated that 15% of all clinically recognizable pregnancies and in spontaneous abortion, 50-60% of which are due to chromosomal abnormalities. Apart from the fetal factors, several maternal and probably paternal factors contribute to the causes of spontaneous abortion. The maternal factors that may be responsible for abortion include both local and systemic conditions such as infections, maternal disease states, genital tract abnormalities, endocrine factors and other miscellaneous causes (antiphospholipid antibodies, maternal fetal histocompatibility, excessive smoking and other environmental toxicants, etc.). This review focuses on the management of threatened abortion, but it should be emphasized that the management to maintain pregnancy is reasonable only in those cases, in which the fetus is not seriously affected. It would not be beneficial to provide treatment that would permit chromosomally and anatomically abnormal embryos to survive to term. Treatment is feasible first of all in cases with maternal factors. Surgical procedures may precede pregnancy (correction of septate uterus, removal of a submucous leiomyomata) or may be performed usually in the second trimester (cervical cerclage). Maternal general diseases (diabetes, hypothyroidism) and infections should be treated accordingly. The most common entity to be treated in this category is luteal phase deficiency. Progesterone is the most important hormone for the maintenance of an early human pregnancy. Besides progesterone administration, human chorionic gonadotropin (hCG) also is the logical endocrine treatment of choice. In the pregnant woman hCG stimulates and optimizes hormonal production in the corpus luteum and may also influence the fetoplacental unit. The contribution of environmental, physical and chemical agents to the incidence of spontaneous abortion is controversial. They may be abortifacient even if they are not teratogenic. Exposure to environmental toxicants should be avoided. Paternal leukocyte immunotherapy has been associated with successful outcome in patients with unexplained repeated spontaneous abortion. This therapeutic approach is considered experimental, as there may be some significant risks. Associating maternal antiphospholipid antibodies with reproductive failure is a rapidly developing field. Administration of corticosteroids with low doses of aspirin has resulted in fetal salvage in women in whom antiphospholipid antibodies are present. PMID- 9363222 TI - A stroll across the epigenetic landscape: bringing Waddington's ideas into molecular biology. PMID- 9363223 TI - The novel role of 3',5'-guanosine monophosphate (cGMP) on the differentiation of trophoblasts: comparison with the effects of 3',5'-adenosine monophosphate (cAMP). AB - We investigated the effects of 3',5'-guanosine monophosphate (cGMP) on the differentiation of human trophoblasts. Isolated cytotrophoblasts were cultured with 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP) or 8-bromoadenosine 3'5-cyclic monophosphate (8-Br-cAMP) and then stained immunocytochemically with anti-human chorionic gonadotropin (anti-hCG) antibody to identify hCG expression as an index of differentiation. Concurrently, morphological changes from cytotrophoblasts to syncytiotrophoblasts were analyzed. Both 8-Br-cGMP and 8-Br cAMP enhanced the expression of hCG in cultured cytotrophoblasts with the differentiation of cytotrophoblasts to syncytiotrophoblasts dose-dependently. With regard to trophoblast proliferation, 8-Br-cAMP but not 8-Br-cGMP enhanced [3H]thymidine uptake by these cells. hCG, a trophoblast-specific glycoprotein hormone has been identified as a potent growth factor for trophoblasts, also increased [3H]thymidine uptake and the intracellular 3',5'-adenosine monophosphate (cAMP) concentration. However, in this study, hCG did not increase the concentration of intracellular cGMP. We also showed that sodium nitroprusside (SNP), which is a donor of nitric oxide (NO), enhanced intracellular cGMP concentration. These results suggest that cGMP enhances trophoblast differentiation without affecting their proliferation, while cAMP enhances both differentiation and proliferation. We conclude that an alternative pathway mediated through cGMP is responsible for the differentiation of trophoblasts. NO may be involved in trophoblast differentiation with an increase in cellular cGMP level. PMID- 9363224 TI - Induction of connexin 32 expression by potential embryonic signals in rabbit uterine epithelium. AB - Connexin 32 induction is found in rabbit uterine epithelium as a response to embryo recognition. Here we have chosen this connexin 32 expression as a cell biological marker to define the type of a locally acting embryonic signal. 17 beta-estradiol, onapristone, catechol estrogen (4-hydroxy-estradiol), prostaglandins E2 and F2 alpha, db-cAMP, and glass beads as mechanical stimuli were given to pseudopregnant animals on day 4, 5 or 6 posthuman chorionic gonadotropin (hCG). The induction of connexin 32 corresponded to the time of implantation at days 6-8 post-hCG by immunohistochemistry and Northern blot analysis. Untreated pseudopregnant animals started to express connexin 32 on day 8 post-hCG. In animals treated with 4-hydroxy-estradiol, 17 beta-estradiol or prostaglandins, connexin 32 expression started 1 day earlier (day 7 post-hCG) and led to an enhanced connexin 32 expression on day 8 post-hCG compared to control animals. The antigestagen, onapristone, as well as cAMP did not alter the endogenous program. Mechanical stimuli led to a high expression of connexin 32 starting at day 7 post-hCG whereas in pregnancy the blastocyst induces connexin 32 expression from day 6 postcoitum onwards. Combination of mechanical stimuli with 17 beta-estrogen advanced the induction to day 6 post-hCG. We conclude that a mechanical stimulus in combination with 17 beta-estradiol induces connexin 32 synthesis in a similar manner as compared to the blastocyst during pregnancy. PMID- 9363225 TI - Influence of uterine growth factors on blastocyst expansion and trophoblast knob formation in the rabbit. AB - The effects of insulin-like growth factors (IGF-1 and IGF-2) on blastocyst expansion, and of basic fibroblast growth (FGF-2) on trophoblast knob formation were studied by in vitro culture of rabbit blastocysts. Both growth factors are present in the uterine secretions. Embryo culture was carried out in Ham's F10 supplemented with polyvinylpyrrolidone in the presence or absence of human recombinant growth factors in concentrations ranging from 1 to 100 ng/ml. IGF-1 stimulated expansion of late preimplantation blastocysts to levels found in vivo; after addition of 10 ng/ml, day-6.0 blastocysts increased their diameter within 24 h to 103% of that of day-7.0 blastocysts expanded in vivo (in comparison to 84% without growth factor), and day-7.0 blastocysts expanded to 108% (in comparison to 76% without growth factor). IGF-1 suppressed the synthesis of a pH 6.3/35-kDa protein. Addition of IGF-2 had no effects. FGF-2 effected formation of trophoblast knobs in day-7.0 blastocysts. After addition of 10 ng/ml, the trophoblast knobs appeared within 12 h of culture. The controls without FGF-2 were negative. The striking increase of FGF-2 concentration in the uterine secretion at day 7.0 is perhaps connected with the formation of trophoblast knobs in vivo. FGF receptor-1 was localized in the trophoblast knobs of day-7.5 blastocysts by the use of immunostaining. PMID- 9363226 TI - Human first-trimester placenta intra-arterial trophoblast cells express the neural cell adhesion molecule. AB - The supposed influence of endometrial natural killer (NK) cells on the trophoblast invasion activities especially on intravasation of uteroplacental arteries in the non-pathogenic human first-trimester placenta was studied by means of immunohistochemistry. To identify extravillous trophoblast cells, smooth muscle cells, endothelia, endometrial glands, decidual stroma cells and endometrial NK cells, antibodies against cytokeratins, vimentin, smooth muscle cells, epithelium specific antigen and endothelial cells were employed. Furthermore, the immunohistochemical distribution patterns of CD56, CD57 and CD94 were studied and compared with the localization of invading trophoblast cells. Remodelling and dilatation of uteroplacental arteries starts before trophoblast cells can be found in the vicinity of the vessels. Nevertheless, subsequent trophoblast invasion of the arterial wall will lead to media destruction and intravasation only on focally restricted areas. This process is accompanied by the disappearance of endothelial cells and the immediate expression of the neural cell adhesion molecule (N-CAM, CD56) by intra-arterial trophoblast cells, which are eventually beginning to form intraluminal plugs. These findings led us to the conclusion that in the human pregnancy-induced physiological changes of the uteroplacental blood flow and the peripheral blood NK cell activity is not only, but also, due to the effect of CD56 expression by intra-arterial trophoblast cells. PMID- 9363227 TI - Current progress in early pregnancy investigation. PMID- 9363228 TI - Developing biotechnological and pharmacotherapeutic advances in early pregnancy. PMID- 9363229 TI - New frontiers in early pregnancy investigation. PMID- 9363230 TI - Will PAPP-A be a biochemical marker for screening of Down's syndrome in the first trimester? PMID- 9363231 TI - Immunotherapy for recurrent spontaneous abortion. AB - Recurrent pregnancy loss is a healthcare concern. Safe and effective treatments are necessary. Since women experiencing recurrent pregnancy loss are a heterogeneous population, specific markers are necessary to identify those who will respond to various treatments. The presence of antiphospholipid antibodies identifies women with recurrent pregnancy loss who are most likely to respond to heparin and aspirin treatment. An elevated concentration of NK cells in maternal blood and a loss of karyotypically normal embryos after detection of cardiac activity on ultrasonographic examination identify women who are most likely to respond to IVIg treatment. An obstetric history of recurrent primary abortion with an absence of maternal antipaternal lymphocytotoxic antibodies and anti phospholipid antibodies predicts women who are most likely to respond to allogeneic leukocyte immunization. However, the treatment effect is low, with a livebirth rate of 60% which represents an enhancement over no treatment in the range of 8-10%. The difference in livebirth rates between women receiving IVIg therapy as compared to placebo was 28%. Women experiencing recurrent spontaneous abortion who have high, as opposed to low levels of leukocyte antibody do not respond to leukocyte immunization therapy. They do, however, respond to treatment with IVIg--the overall success rate of IVIg being 70%. It is important to be able to identify women likely to respond to various forms of immunotherapy. Chromosomal abnormalities are evident in 60% of recurrent aborters. Women experiencing recurrent aneuploidy in their abortus would not be expected to respond to immunotherapy. At the present time, the only way to identify such women is to have the results of chromosome analysis of previous pregnancy losses available. Having access to this information will require a change in current obstetric practice regarding obtaining karyotyping of all pregnancy losses. The cost-effectiveness of chromosome studies from abortuses is apparent when costs of evaluation and treatment are considered. PMID- 9363232 TI - The correlation of the embryo implantation rate with uterine arterial impedance in in vitro fertilization and embryo transfer. AB - The influence of uterine blood flow impedance on embryo implantation rate was investigated by transvaginal color Doppler sonography examination before embryo transfer. A total of 108 women undergoing in vitro fertilization (IVF) procedures and who had at least one good quality embryo for transfer to the uterus received Doppler evaluation before embryo transfer. Color flow imaging with blood flow waveform analysis from bilateral uterine arteries was obtained to calculate the mean pulsatility index (PI). The correlations between mean PI with the pregnancy rate and the embryo implantation rate (number of embryos implanted/number of embryos transferred) were analyzed. Patients were grouped according to the mean PI value, and the pregnancy rate and embryo implantation rate were 25% (5/20) and 10.7% (9/84), respectively, with a PI < 2.0 (n = 20); 27.5% (14/51) and 12.2% (12/109), respectively, with a PI = 2.00-2.49 (n = 51); 9.5% (2/21) and 3.5% (2/57), respectively, with a PI = 2.50-2.99 (n = 21); and 6.3% (1/16) and 4.3% (2/47), respectively, with a PI [symbol: see text] 3.0 (n = 16). There were no significant differences in either pregnancy rate or embryo implantation rate between the groups with mean PI values less than 2.00 and between 2.00 and 2.49. If a mean PI value of 2.50 was used as the cut-off value, both the pregnancy rate and embryo implantation rate were significantly higher in patients with a mean PI less than 2.50 (p < 0.05). The uterine arterial impedance measured by the Doppler sonographic examination is a non-invasive method for evaluating the endometrial response and a mean uterine PI value of 2.5 can be used as a cut-off value to identify optimal uterine receptivity before embryo transfer. PMID- 9363233 TI - Effect of seminal plasma on implantation rates. AB - The objective of this study was to evaluate the effect of seminal plasma on implantation rates. A prospective randomized placebo-controlled clinical trial was designed, and carried out at the Center for Reproduction and Transplantation Immunology. Eighty-seven women experiencing unexplained infertility and/or recurrent spontaneous abortion were recruited into the study and were randomized into groups using vaginal capsules containing seminal plasma or placebo (lubrication jelly). Implantation rates documented by the appearance of an intrauterine gestational sac visible on transvaginal ultrasonographic examination by the 6th week of gestation were compared between women receiving either seminal plasma or placebo. The results obtained from this study demonstrated that, of the 87 women participating in the study, 23 (26%) did not achieve pregnancy within 1 year. Nine of these infertile women received seminal plasma and 14 received placebo. Implantation rates were higher among women receiving seminal plasma (35/44, 80%) compared to placebo (29/43, 67%). The conclusions drawn from this study suggest that vaginal capsules containing seminal plasma appear to enhance implantation. They, therefore, may be useful in the treatment of couples undergoing assisted reproductive technologies or with unexplained infertility. PMID- 9363234 TI - Possible existence of luteinizing hormone/chorionic gonadotropin receptors in human corpora lutea during early pregnancy. AB - In order to evaluate the possible existence of receptors for luteinizing hormone (LH)/chorionic gonadotropin (CG) in human corpora lutea of pregnancy, the specific binding of [125I]hLH to luteal pellets of 6-7 weeks' gestation and the effect of neuraminidase pretreatment on [125I]hLH binding were investigated. A relatively low capacity of hLH binding to luteal tissue of pregnancy was observed. In addition, the specific binding of hLH to luteal pellets significantly increased following neuraminidase pretreatment. The results obtained in this study suggest the possible existence of LH/CG receptors in human corpora lutea of pregnancy. PMID- 9363235 TI - Human trophoblast interferons: production and possible roles in early pregnancy. AB - Human villous and extravillous trophoblast populations were isolated from first- and third-trimester placentae and were stimulated with viral and non-viral inducers to produce interferons (IFNs). Polyriboinosinic/polyribocytidylic acid [poly(I:C)] induced exclusively IFN-beta in trophoblast cultures, whereas viruses induced mixtures of IFN-alpha subtypes and -beta. The level of IFN production was dependent on the trophoblast population, type of inducer and the stage of differentiation of the trophoblast. First-trimester extravillous trophoblast cultures produced greater than five-fold more IFN than third-trimester villous trophoblast on a per cell basis, whereas term syncytiotrophoblast produced twice as much IFN as term mononuclear villous trophoblast when stimulated with the same inducer. Pretreatment of trophoblast cultures with platelet-derived growth factor and granulocyte/macrophage-colony stimulating factor (GM-CSF) increased the trophoblast IFN production. Tandem high-performance affinity chromatography of the virus-induced trophoblast IFNs resulted in the isolation of trophoblast IFN alpha and -beta with specific antiviral activities of 0.75-2.73 x 10(8) IU/ml protein. The trophoblast-induced IFNs have antiproliferative and immunosuppressive properties, and, furthermore, activated natural killer cell activity. These data may suggest the possible roles of these IFNs during embryonic development with regard to protection of the fetus against viral infection and maternal immunity. PMID- 9363236 TI - Insulin-like growth factor-I as a local regulator of proliferation and differentiated function of the human trophoblast in early pregnancy. AB - In order to elucidate the role of insulin-like growth factor-I (IGF-I) in human placental growth and function, the effects of IGF-I on the proliferation and differentiation of trophoblasts were investigated using an organ culture system of early placental tissues. Explants of trophoblastic tissues obtained from 4-5 week or 6-12-week placentae were, respectively, cultured with or without IGF-I, in a serum-free condition. The effect of IGF-I on the proliferative activity of trophoblasts was examined by immunocytochemical techniques with a monoclonal antibody to proliferating cell nuclear antigen (PCNA), while the effect of IGF-I on the differentiated function of trophoblasts was assessed by determining the ability to secrete human chorionic gonadotropin (hCG) and human placental lactogen (hPL). In 4-5-week placentae, IGF-I and IGF-I receptor were almost exclusively localized in cytotrophoblasts and IGF-I augmented the proliferative activity of cytotrophoblasts without affecting the ability to secrete hCG and hPL. By contrast, in 6-12-week placentae, IGF-I and IGF-I receptor were localized in both cytotrophoblasts and syncytiotrophoblasts and IGF-I stimulated the secretion of hCG and hPL following the enhancement of the proliferative activity of trophoblasts. In column chromatography of the serum-free medium obtained following 5-day culture of early placental tissues, an elution peak of immunoreactive IGF-I was found in the fractions similar to the elution region of [125I]IGF-I. These findings suggest that IGF-I acts as an autocrine/paracrine factor in regulating early placental growth and function. PMID- 9363237 TI - Sources of inhibin in early pregnancy. AB - Inhibin is a glycoprotein which suppresses the release of follicle stimulating hormone (FSH) from the pituitary. Plasma immunoreactive inhibin levels during pregnancy have been reported to be higher than those during the normal menstrual cycle. In the present study, we investigated the cellular localization of inhibin alpha-, beta A-, and beta B-subunits in the human corpus luteum and placenta during early pregnancy. Luteal cells and theca luteal cells in the corpus luteum of pregnancy exhibited positive staining for all three inhibin subunits. We also observed positive staining with antisera against each inhibin subunit in the syncytiotrophoblast, but not in the cytotrophoblast, in the villi during early pregnancy. The staining with antisera against inhibin alpha- and beta A-subunits was clearly observed, whereas the staining for the beta B-subunit was faint. These results suggest that the gestational corpus luteum and the villous tissue may be major sources of inhibin during early pregnancy. PMID- 9363238 TI - A non-trophoblastic tumor co-existing with a triploid fetus. AB - Non-trophoblastic neoplasms are the most frequent, benign tumors of the placenta, occurring in approximately 1% of all placentas examined. A case is described of a 24-year-old woman who presented with severe, early-onset pre-eclampsia, high human chorionic gonadotropin (hCG) levels, and a triploid fetus and who was found to have a small choriohemangioma. The woman, gravida 2 para 1, was referred to our hospital for perinatal evaluation. The fetus, gestational age 18 weeks 3 days, had fetal growth restriction with multiple congenital anomalies. The fetal karyotype was 69,XXY. Compared with the normal range for this gestational age, the beta-hCG level was significantly elevated (1,054,000 mIU/ml) as was the maternal serum alpha-feto-protein measurement (539.1 ng/ml). Sonographically, the placenta appeared hydropic, irregularly shaped, and gelatinous. A suction dilatation and evacuation under sonographic guidance was performed. Histological examination of placental tissue revealed hydropic degeneration of the chorionic villi. The specific histological features of a partial molar pregnancy were not present. However, there were changes consistent with a choriohemangioma. Flow cytometric DNA analysis performed on formalin-fixed, paraffin-embedded tissue blocks of placenta showed triploidy. Immunohistochemical staining with human placental alkaline phosphatase was consistent with a hydropic degeneration pattern. We conclude, first, that triploidy does not always imply the presence of a partial mole. Second, the dictum, that pre-eclampsia, if it occurs under 20 weeks' gestation, must be associated with a molar pregnancy, may not hold when placental aneuploidy is present. Although the findings in this pregnancy could have been incidental, there may be an association between a choriohemangioma and polyploidy. PMID- 9363239 TI - Current progress in early pregnancy investigation. PMID- 9363240 TI - Fecundity in autoimmune diseases. PMID- 9363241 TI - Biochemical and sonographic evaluation of the very early intrauterine pregnancy. PMID- 9363242 TI - Regulation of placental prorenin secretion from the early human placenta in vitro. AB - The presence of all components of the renin-angiotensin system within the human placenta appears to be well established, but their function and regulation remain obscure. In order to approach this question, placental tissue explants (50 mg) from early human placenta (9-12 weeks of gestation) were cultured in Medium 199. Prorenin was measured by direct immunoradiometric assay in the daily replaced culture medium. In a further series of experiments, progesterone, a progesterone antagonist (ZK 98,299) or estradiol was added to the medium at final concentrations of 10(-4)-10(-8) mol/l. Prorenin was detectable in the culture medium of early human placental explants, and prorenin values were decreased by progesterone in a dose-dependent manner. Progesterone antagonist and estradiol could also inhibit prorenin secretion, but the inhibition was less prominent. When progesterone and progesterone antagonist were co-administered at equimolar concentration, a decrease in prorenin secretion occurred, but it could not reach the inhibitory effect of progesterone given alone. It is concluded that prorenin activity is present in the early human placenta, and prorenin secretion may be influenced by progesterone and estradiol. Regulation of prorenin secretion by steroid hormones is partly similar to that of human chorionic gonadotropin, but its physiological significance awaits further exploration. PMID- 9363243 TI - Production of superoxide dismutase, beta 2-microglobulin and ubiquitin by human term decidua in vitro. AB - In order to study decidual proteins produced during pregnancy, decidual cells were isolated from term placental membranes by collagenase digestion and Percoll gradient centrifugation. Serum-free CMRL-1066 medium, conditioned for 148 h with the purified decidual cells, was collected and concentrated by ultrafiltration and applied to a Sephadex G-50 column. The protein-containing fractions from the column were concentrated, dialyzed, lyophilized, applied to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and transferred to a polyvinylidene difluoride membrane, followed by sequencing. Superoxide dismutase and two new members of the decidual protein family, beta 2-microglobulin precursor and ubiquitin, were identified by 100% N-terminal sequence homology, and similarities of molecular weights and residue contents. PMID- 9363244 TI - Does occupational nuclear power plant radiation affect conception and pregnancy? AB - OBJECTIVES: To determine the effect of occupational exposure in a nuclear power plant in Griefswald, Germany on male and female fecundity. METHODS: The frequency of men and women exposed to ionizing radiation through work in a nuclear power plant among 270 infertile couples was retrospectively compared to a control fertile population using a pair-matched analysis. The total cumulative equivalent radiation dose was determined. In addition, the spermiograms of the male partners in both groups were compared and correlated to the degree of exposure. RESULTS: No differences were noted in the frequency of nuclear power plant exposure between sterile and fertile groups. There was a higher rate of anomalous spermiograms in nuclear power plant workers. However, abnormalities were temporary. No correlation was found between the cumulative equivalent radiation dose and abnormal spermiograms. CONCLUSION: The data suggest that occupational exposure due to ionizing radiation should be investigated as a possible cause for involuntary temporary sterility and as a risk factor for early pregnancy disorders. PMID- 9363245 TI - Production of endometrial placental protein 14 and prolactin by cultured endometrial explants after collagenase and freeze/thaw treatment, and in response to progesterone. AB - OBJECTIVE: Investigation of methods for maintaining functional endometrial explants in culture after cryopreservation with or without previous enzymatic dispersion of stromal cells and epithelial glands. Such a standardized culture system is a requirement for the development of a non-invasive bioassay for embryo quality in in vitro fertilization programs, a method that will eventually measure endometrial response to embryo conditioned media. METHOD: Culture of mid-luteal phase endometrial biopsies, in the presence of [35S]methionine, with or without prior collagenase treatment and/or storage in liquid nitrogen in the presence of dimethyl sulfoxide. Determination of released de novo synthesized total protein by trichloroacetic acid precipitation of culture media. Measurement, after culture in absence and presence of progesterone, of prolactin and placental protein 14 (PP14) production by sensitive non-isotopic immunoassays. RESULTS: Production of prolactin, but not PP14, was increased by 200 nmol/l progesterone, 2-8-fold after 4 days and 1.5-700-fold after 7 days in culture. After limited collagenase treatment (but without separation of stromal cells from glands), both marker protein productions were similar compared to untreated explants; however, there was no significant stimulation of prolactin by progesterone. After freezing and thawing, production was markedly reduced, particularly from explants frozen following collagenase treatment. CONCLUSIONS: Both stromal and glandular viability are maintained after collagenase treatment but the response to progesterone is lost. Cryopreservation reduced prolactin and PP14 production in subsequent culture. Therefore, novel freezing protocols should be developed which preserve both endometrial structure and function. PMID- 9363247 TI - Current progress in early pregnancy investigation. PMID- 9363246 TI - Peroxidase activity and glutathione content in the human first-trimester placenta and decidua. AB - OBJECTIVE: Recently, a novel pathway of xenobiotic oxidation by peroxidase in the placenta at term was described. Herein, we aim to determine the potential of the first-trimester placenta and decidua to activate carcinogens and mutagens by peroxidase and to scavenge free radicals by glutathione. METHODS: Placental and decidual peroxidase activity was measured using a sensitive, quantitative colorimetric kinetic assay, with O-phenylenediamine dihydrochloride (OPD) as substrate and H2O2 as co-substrate. Glutathione levels were measured using a colorimetric assay. RESULTS: Peroxidase activity in cytosolic and CaCl2-extracted (membrane-bound) fractions was inhibited by a specific inhibitor, NaN3. The membrane-bound peroxidase activity was maximal at 12 weeks of gestation while cytosolic peroxidase activity did not change. Placental glutathione content remained unchanged during the first trimester. Decidual and placental peroxidase activities were similar; however decidual glutathione content was 15-fold lower, resulting in a higher decidual peroxidase activity/glutathione ratio (p < 0.03). CONCLUSIONS: We report for the first time that peroxidase may be an important pathway for xenobiotic activation at the maternal-embryonal interface. It remains to be established whether the low glutathione content limits the ability of the decidua but not placenta to protect against genomic damage induced through xenobiotic oxidation. PMID- 9363248 TI - Abortion rate in assisted reproduction--true increase? AB - Pregnancies achieved by assisted reproduction were considered to carry an increased risk for spontaneous abortion, and ectopic and heterotopic pregnancies. In order to examine the validity of this hypothesis we compared the outcomes of spontaneous pregnancies and assisted reproduction pregnancies using the published reports in the world literature during the last decade. We also studied the outcome of 53,928 in vitro fertilization (IVF) pregnancies reported during the years 1985-91. The reported loss rates in spontaneous pregnancies (abortions and ectopic pregnancies) compared to pregnancies achieved by assisted reproduction were 19% and 30%, respectively. The differences in loss rates between spontaneous and assisted reproduction pregnancies are not completely understood and may originate from predisposing factors such as tubal disease, uterine disorders, corpus luteum dysfunction, and endometriosis that are more frequent in patients suffering from infertility. Increasing maternal age correlates with a higher risk of fetal chromosomal anomalies which results in an increased rate of abortions. PMID- 9363249 TI - A novel perspective on the role of human chorionic gonadotropin during pregnancy and in gestational trophoblastic disease. AB - We have discussed recent new findings on the presence and function of hCG/LH receptors in non-gonadal tissues with particular emphasis on the placenta. These findings support the hypothesis that hCG plays a broader role throughout pregnancy than previously believed. Since hCG is widely used in reproductive medicine, the possible impact of hCG treatment on non-gonadal tissues must be considered. In addition, the possible consequences of a relative excess or deficiency in hCG production or possible structural and functional defects in hCG and/or in its hCG receptors during pregnancy should be realized. PMID- 9363251 TI - The effect of short- vs. long-term platelet-activating factor exposure on mouse preimplantation embryo development. AB - Preimplantation mouse embryos (n = 1540) were cultured in the presence of platelet-activating factor (PAF) (10(-7)- 10(-14) mol/l) to the hatched blastocyst stage. A dose-dependent negative correlation (-0.75783) relationship between blastocysts and the concentration of PAF was statistically significantly different (p < 0.001). Long-term but not short-term PAF exposure is detrimental to preimplantation Swiss Webster mouse embryos. Short-term PAF (10(-9) mol/l) exposure was found significantly (p < 0.05) to reduce blastocoel diameter. The effect of PAF during preimplantation development may be genotype dependent and be affected by the culture conditions. PMID- 9363250 TI - Endothelins inhibit FSH-mediated function via ETA receptors in cultured human granulosa-lutein cells. AB - Endothelins (ETs) are a family of vasoactive peptides involved in granulosa and luteal cell function in some animal species. However, the potential relevance of ETs in ovarian physiology remains unclear, and the direct action of the peptides in the human ovary has not been studied to date. Experiments were conducted to determine whether ET-1 and ET-3 could regulate the follicle stimulating hormone (FSH)-induced cell response in human granulosa-lutein cells in culture. The FSH mediated cell rounding process was used as an indicator of cell response, as previously described (Lawrence et al., 1979). Forskolin, cholera toxin, 8-Br cyclic AMP, isobutylmethylxanthine (IBMX), rolipram and FSH all stimulated similar cell morphological changes, indicating that the cell rounding process was mediated by cyclic AMP. Although ET-1 and ET-3 alone failed to alter cell shape, the FSH-induced cell response was totally inhibited by treatment with ET-1 (10( 10) mol/l) and ET-3 (10(-7) mol/l). In addition, treatment of the cells with BQ123, an antagonist of ET binding on ETA receptor subtype, totally prevented the inhibitory effects of ET-1 and ET-3 on the FSH-induced response. The data presented here show that human granulosalutein cells are a site of ET reception and action. Endothelins inhibit cyclic AMP-dependent FSH-mediated function and the ET(A) receptor participates in this effect. PMID- 9363252 TI - Interleukin-1 alpha in the rabbit uterus during early pregnancy. AB - Immunoreactive (ir) interleukin-1 alpha (IL-alpha) was present in the endometrium and myometrium of the rabbit uterus during early pregnancy. Interleukin-1 alpha was at a high level in endometrial epithelium from days 3 to 6 of pregnancy. A similar level of IL-1 alpha was detected on day 6 of pseudopregnancy. Interleukin 1 alpha declined rapidly on day 7 at both the implantation and non-implantation areas. Our results suggest that IL-1 alpha may play a role in rabbit blastocyst implantation. PMID- 9363253 TI - The relationship of corpus luteum volume to relaxin, estradiol, progesterone, 17 hydroxyprogesterone and human chorionic gonadotropin levels in early normal pregnancy. AB - Our purpose was to characterize the growth pattern of the corpus luteum of early normal human pregnancy and correlate this growth with the corpus luteum hormone products: relaxin, progesterone, estradiol and 17-hydroxyprogesterone. A prospective study of seven patients was initiated at a mean gestational age of 4 weeks and 2 days. Corpus luteum volume and hormone concentrations were determined for each study patient every 48 h for a period of 2 weeks. Transvaginal imaging of the corpus luteum was performed by a single observer. Corpus luteum volume was calculated using the formula for an ellipsoid (4/3 pi abc/8). Correlation between corpus luteum volume and hormone concentrations was tested using Pearson's r. There was a mean three-fold increase in corpus luteum volume between 4 and 6 weeks' gestational age. Concomitantly, relaxin and estradiol concentrations increased, 17-hydroxyprogesterone declined slightly, progesterone remained stable and human chorionic gonadotropin (hCG) increased exponentially. Mean positive correlations were shown between corpus luteum volume and relaxin (r = 0.72), corpus luteum volume and hCG (r = 0.68), and hCG and relaxin (r = 0.82). However, there was a lack of correlation between corpus luteum volume and estradiol, progesterone and 17-hydroxyprogesterone. We have shown that a rapid increase in the corpus luteum volume occurs in early normal human pregnancy without a parallel rise in the classic corpus luteum steroid products. We interpret these findings to suggest that growth of the corpus luteum in early human pregnancy is largely derived from the proliferation of non-steroid secreting cells. The precise role of these cells in controlling steroidogenesis in this gland has yet to be defined. PMID- 9363254 TI - Current progress in early pregnancy investigation. PMID- 9363255 TI - Use, risks and complications of amniocentesis and chorionic villous sampling for prenatal diagnosis in early pregnancy. PMID- 9363256 TI - Ethical implications for early pregnancy of the fetus as patient: a basic ethical concept in fetal medicine. AB - The viable fetus is a patient. The previable fetus, including the in vitro embryo and the near-viable fetus, is a patient solely as a function of the exercise of the woman's autonomy. Directive counseling of the pregnant woman for fetal benefit is appropriate only when the fetus is a patient and must take account of the presence and severity of anomalies, extreme prematurity and beneficence-based and autonomy-based obligations to the pregnant woman. PMID- 9363257 TI - Suspected ectopic pregnancy: expectant management in patients with negative sonographic findings and low serum hCG concentrations. AB - Between July 1989 and December 1994, we performed a prospective study in 265 patients with suspected ectopic pregnancy to assess the value of expectant management in patients with negative transvaginal sonographic findings and low serum human chorionic gonadotropin (hCG) concentrations. All patients had serum hCG concentrations < 1500 IU/l. Eventually, ectopic pregnancy was diagnosed in 68 patients (25.6%), intrauterine pregnancy in 81 patients (30.6%) and trophoblast in regression in 116 patients (43.8%). Test results of our diagnostic strategy, that integrated the results of serial transvaginal sonography, serum hCG monitoring and expectant management, were good: sensitivity 90%, specificity 98%, likelihood ratio of a positive test result 45 and likelihood ratio of a negative test result 0.1. Expectant management in patients with suspected ectopic pregnancy and low serum hCG concentrations proved to be safe, and it enabled us to avoid untimely invasive interventions in patients with an early intrauterine pregnancy or with trophoblast in regression. PMID- 9363258 TI - Importance of matrix metalloproteinases in human trophoblast invasion. AB - Human cytotrophoblast cells are invasive by virtue of their ability to secrete metalloproteinases (MMP) capable of digesting the extracellular matrix of the endometrium. It is the aim of the present study to determine which of the known MMP is responsible for this invasive behavior and to see to what extent endometrial secretions can modulate this enzymatic activity. Under our experimental conditions, first-trimester cytotrophoblast cells invade matrigel; this invasive behavior is inhibited by phenanthroline (an inhibitor of MMP) and by a polyclonal antibody to the 92-kDa gelatinase but not to other MMP. Since cytotrophoblast cells cultured in vitro secrete the 92-kDa gelatinase, and since adhesion to a substrate increases their gelatinolytic activity, it is believed that cytotrophoblast cells invade their surrounding matrix by binding to it and by increasing their secretion of 92-kDa gelatinase which then digests the collagen type IV of their micro-environment. This process of invasion is controlled by secretions from decidual cells (but not from non-decidualized stromal cells) since conditioned medium from decidual cells inhibits the activity of the 92-kDa gelatinase released from cytotrophoblast cells. PMID- 9363259 TI - Culture of first-trimester and full-term human chorionic villus explants: role of human chorionic gonadotropin and human placental lactogen as a viability index. AB - In long-term cultures of human chorionic villus explants, the viability of the tissue must be controlled to ensure the reliability of functional studies. Ionic levels (pH), gas concentrations (pO2, pCO2) and metabolic markers (glucose, lactate) in the culture medium are often utilized. Analyses of hormone, enzyme and protein levels are also frequently used to estimate viability. The purpose of this study was to evaluate whether in vitro release and immunoreactivity of human chorionic gonadotropin (hCG) and human placental lactogen (hPL) were correlated with the viability of first-trimester and full-term chorionic villus explants as determined by histopathology. Villus explants of first-trimester and full-term pregnancies were incubated in 6-well plates of RPMI medium which was supplemented with 10% fetal calf serum. Incubations were performed for 10 days, and the plates were kept at 37 degrees C under a water-saturated atmosphere containing 5% CO2 and 95% O2. The medium was replaced every day and samples of supernatant were frozen for later testing of hCG (first trimester) or hPL (full term), glucose consumption and lactate production. The tissue was also fixed and embedded for light-microscopic examination and immunocytochemistry. The hCG release remained stable during 6-7 days at a high level before decreasing, whereas hPL release decreased during the first 5-6 days then stabilized at a relatively low level. Only hCG kinetics were significantly different between tissue incubated with and without cycloheximide or iodoacetic acid. Both hCG and hPL immunoreactivity were not significantly different between tissue cultures with, and without, addition of cycloheximide or iodoacetic acid and even with morphological evidence of trophoblast and endothelial necrosis. The immunoreactivity for both hormones remains highly positive when the significant release has stopped, and does not reflect the tissue viability. PMID- 9363261 TI - Urine pregnancy tests from antiquity to the present. PMID- 9363260 TI - Active corpus luteum function at pre-, peri- and postimplantation is essential for a viable pregnancy. AB - Luteal-phase estrogen and progesterone concentrations were measured every other day and used to monitor the corpus luteum activity. The patterns of estrogen and progesterone concentrations were compared relative to the day of endogenous human chorionic gonadotropin (hCG) detection (defined as the day of implantation). The relationship between estrogen and progesterone and hCG concentrations was studied in 71 viable pregnancies, 12 clinical abortions, five preclinical abortions and 84 non-pregnant cycles after IVF/ET. Although all patients received luteal-phase progesterone support (25-50 mg/ml), low late luteal-phase progesterone concentrations of < 30 ng/ml from day + 11 to day + 15 were found in 64 patients (17% of viable pregnancies, 33.3% of clinical abortions, 60% of preclinical abortions and 53.6% of non-pregnant cycles) day + 1 was the day of retrieval). Implantation always occurred before or on day + 13 and 86% of pregnant cycles implanted on day + 8 to day + 11. Viable pregnancies had significantly higher mean progesterone concentrations on day + 3 to day + 7 (pre-implantation) and on day + 9 to day + 15 (postimplantation) than those of non-pregnant cycles or abortions. On the day of implantation, the mean +/- standard of deviation of estrogen (pg/ml) and progesterone (ng/ml) levels for viable pregnancies, clinical abortion and preclinical abortions were 314 +/- 210, 40.5 +/- 25; 226.7 +/- 246, 48.7 +/- 31; and 39.6 +/- 24.5, 28.6 +/- 24.5, respectively. On the same day, 73.2% of viable pregnancies, 41.7% of clinical abortions, and 20% preclinical abortions had a progesterone concentration > 30 ng/ml; 73.2% of viable pregnancies, 41.7% of clinical abortions and 20% of preclinical abortions had an estrogen concentration > 100 pg/ml. Although not precluding implantation completely, late luteal-phase hormonal deficiencies may impair endometrial growth and might ultimately lead to failure or abnormal implantation. A viable pregnancy requires not only a functional corpus luteum in the early luteal phase to develop a receptive endometrium, but also a responsive corpus luteum in the late luteal phase to support pregnancy. The time of implantation is critical. Implantation that occurs before the demise of the corpus luteum will facilitate a normal pregnancy. PMID- 9363262 TI - Current progress in early pregnancy investigation. PMID- 9363263 TI - Helicobacter pylori in recently-diagnosed versus chronic duodenal ulcer. AB - Helicobacter pylori is one of the main causes of type B gastritis and is frequently found in the gastric antrum or in areas of gastric metaplasia in duodenal ulcer patients. The aim of this study was to evaluate Helicobacter pylori and gastric metaplasia prevalence in duodenal ulcer patients within their first diagnosed episode compared to those with chronic ulcer disease. Eighty three patients were prospectively studied in a 2-year period, they were divided into 3 groups: Group I, control, included 29 patients; Group II, 17 patients, included patients with first diagnosed duodenal ulcer episode; and Group III, 37 patients, with chronic ulcer disease. Helicobacter pylori prevalence in duodenum was significatively lower in Group II versus Group III and controls (67.5%, 0% and 3.2% respectively) (p < 0.001). In the antrum Hp prevalence was also lower in Group II compared to Group III and I (41%, 78.3% and 24.1%) with a significative difference (p < 0.001). Gastric metaplasia was significantly higher in Group III versus Group II and controls. These results suggest that Helicobacter pylori plays an important but not exclusive role in the pathogenesis of these disease together with other factors. PMID- 9363264 TI - [Comparison of quinfamide vs etofamide in the Mexican population with intestinal amebiasis]. AB - An open comparative, prospective and randomized study was carried out to evaluate the efficacy and safety of quinfamide and etofamide in the treatment of intestinal amebiasis. This study evaluate two populations: children (1-16 years) and adults (17-80 years). The drugs used were quinfamide at doses of 4.3 mg/kg b.i.d. in children, and 100 mg t.i.d. adults both for one day; and etofamide at doses of 200 mg t.i.d. in children and 500 mg b.i.d. in adults both for three days. A total of 110 patients were included, 54 in the quinfamide group and 56 in the etofamide group. No significant difference between groups in baseline demographics characteristics were observed. Global healing rate for quinfamide group was 87% and for etofamife group was 76.8% (p = 0.0696). This difference was similar considering both group of populations. It is concluded that the therapeutical response was better for the quinfamide group than for the etofamide group. Both drugs have the same safety profile. PMID- 9363265 TI - [Elimination of Helicobacter pylori in patients with recurrent abdominal pain with simultaneous administration of ranitidine, bismuth subsalicylate and clarithromycin]. AB - OBJECTIVE: Elimination of Helicobacter pylori with Chlaritromicin, Bismuth subsalicylate and Ranitidine; and improvement of recurrent abdominal pain. ANTECEDENT: Different antibiotics, antagonist H2 and others has been used for elimination and, or eradication of Helicobacter pylori. METHOD: 22 children with recurrent abdominal pain associated to gastritis and histologic identification of Helicobacter pylori were studied under a period of 18 months (january 1992 to june 1993), at Instituto Nacional de Pediatria, Mexico, D:F: All children were treated simultaneously with: Chlaritromicin, 15 days, Plus ranitidine and bismuth subsalicylate for one month. RESULTS: Helicobacter pylori was eliminate in 14 of 22 children studied. All these children had an important improvement of recurrent abdominal pain. CONCLUSION: Elimination of Helicobacter pylori and clinical improvement was present in 14 of 22 children studied (63.7%). PMID- 9363267 TI - [History of the gastroenterology service at the Alejandro Posadas Hospital]. PMID- 9363266 TI - [Electrogastrography and gastric emptying in non organic dyspepsia]. AB - Electrogastrography allows to determinate the dominant frequency of gastric E.C.A. (electrical control activity). The aim was to investigate the gastric E.C.A. in a population of patients suffering from non-organic dispepsia (N.O.D.). Eighteen controls (9 males, 9 females, mean age 46.4 years old, SEM 3.72, range 24-72) and 52 dyspeptic patients (18 males, 34 females, mean age 54.19 years old, SEM 2.38, range 17-86) were studied. Two skin surface electrodes Ag-2ClAg were placed on epigastric area following a probabilistic antral axe. Reference electrode was placed on the right quadrant skin. In 5 patients, recordings with needle and cutaneous electrode were compared. Analogic waves were filtered, digitalized and processed. Signals were analyzed using F.F.T. (Fast Fourier Transformated) Only the predominant frequency in each block was considered, and percentage of total abnormalities on total recording time lesser than 2 c.p.m. or more than 4 c.p.m. was accepted. Recording were taken in fast time during 30 minutes, and 30 minutes after a meal containing 230 Cal. Running spectral analysis with F.F.T. In 43 non-selected patients the gastric emptying time of a mixed meal marked with 99 Tc in the solid phase was studied. RESULTS: 60.45% showed delayed gastric emptying. Mean of fast E.C.A. was 2.99 c.p.m. in controls, Vs 3.34 c.p.m. in dispeptic patients (p > 0.001). In the post-prandial period, mean of E.C.A. was 3.53 c.p.m. in N.O.D., and these differences were not significatives ("t", NS). 22% of controls showed isolated periods of tachygastria, but never more than 8% of the total recording time. It was seen seven six and forty five percent of arrhythmias were observed (71.15% tachygastria, 4.76% bradygastria, and 19.23% mixed) during post prandial recording in N.O.D. 48% of tachygastrias were between the range 30-60% of the time recording. Ninety six and one percent of patients with abnormal gastric emptying had gastric arrhythmias (0.05 > p > 0.02) Vs 50% in patients with normal gastric emptying. Needle recording increased about 200-300% the signal power. It would be the better choice in cases of hairy abdominal skin. CONCLUSIONS: a) More than 76% of patients with N.O.D. had abnormal recording of E.C.A. beyond these observed in controls; b) tachygastria was the more frequent abnormality observed; c) the more severe clinical cases were associated with bradygastria; d) No association between symptoms and abnormal gastric emptying was found; e) E.G.G. abnormalities were seen in 96% of patients with abnormal gastric emptying, Vs 50% in normal gastric emptying; f) Needle electrodes let a better recording of E.G.G. signal; g) No association was found between abnormalities in gastric emptying and/or E.G.G., and clinical subtypes of Dyspepsia. PMID- 9363268 TI - [Prevalence of antibodies against hepatitis C virus (HCV) in a population of Mexican children]. AB - We studied 450 healthy children between 3 months old and 17 years old who were seen at the Instituto Nacional de Pediatria during a period of one year (September 1992 June 1993). The EUSA test was positive in 4/450, 0.9%. The RIBA test was positive in these four children. PMID- 9363269 TI - [Esophageal stenosis in children. Complications of esophageal dilatations (Part III)]. PMID- 9363270 TI - [Brain metastases in cancer of the anal canal: a case report]. AB - One to two per cent of the GI tract cancers have its origin in the anal canal. The purpose of this publication, is to report a case of a patient with the unusual complication of brain and bone metastases which is believed to be due to hematogenous spreading. PMID- 9363271 TI - [Non-ulcer dyspepsia or gastric dyskinesia dyspepsia]. AB - The non ulcer dyspepsia (N.U.D) syndrome is a functional disease; according with new concepts obtained from pharmacology and sustented by therapy, the anti H2 drugs (not the antacids one) has an prokinetic action upon the stomach and control the gastric distention which is the cause of the pain, and not the increase of the gastric acidity. For these reasons and by observing the good response to therapy, the author proposed the name of Gastric Dyskinesia Dyspepsia. PMID- 9363272 TI - [Clinical remission of colonic endometriosis with danazol: case report and bibliographic considerations]. AB - A case of a 42 years-old woman suffering from lower abdominal pain, constipation and rectal bleeding during menses is reported. A barium enema showed an extrinsic filling defect on the rectosigmoid junction. Laparoscopy confirmed the clinical suspicion of endometrosis. She received danazol for a 6-month period during which she developed adverse effects that disappeared when the drug was discontinued. The patient remained asymptomatic after two years of follow up. Data from literature concerning diagnostic and treatment techniques are discussed. PMID- 9363273 TI - [Hepatitis C in pediatrics]. PMID- 9363274 TI - [The 100th birthday anniversary of Doctor Marcelo R. Royer]. PMID- 9363276 TI - How to use low-flow techniques for new inhalation agents? PMID- 9363275 TI - Inhalation anesthesia. What to learn from modelisation? AB - Models describing pharmacokinetics of inhalational anesthetic agents have been developed, usually on Mapleson's description of the body as a collection of tissues characterised by their volume, local blood flow and anesthetic solubility. Such models are very useful to understand the use of inhalation agents and circle circuit, to compare consumption of different agents in different anesthetic practices, and to prepare the anesthetist to administer new products safely. PMID- 9363277 TI - Sevoflurane mask induction in adults: comparison of two inhalation techniques. AB - The efficacy and safety of two inhalation techniques for mask induction using high concentrations of sevoflurane (8%) were compared in female patients planned for short gynecological procedures in an out-patient setting. One group (n = 20) received single breath vital capacity rapid inhalation induction (VCRII), the other group (n = 20) multiple deep breaths inhalation induction (DBI). The induction time was short and comparable in both groups (70 +/- 4 and 62 +/- 3 seconds respectively). The respiratory and hemodynamic side effects were also similar. The appreciation of the induction technique was comparable in both groups and most patients agreed to the same inhalation technique with a mask in future anesthetics. PMID- 9363278 TI - Cost containment in inhalation anesthesia: the best way. PMID- 9363279 TI - Inhalation versus TIVA in short duration anaesthesia. PMID- 9363280 TI - New approaches to anesthesia for day case surgery. AB - Anesthesia for day case or ambulatory surgery must be specifically tailored to meet its specialized goals, and the use of sevoflurane helps to meet these goals. Maintenance of sevoflurane anesthesia is associated with good titratability and short early recovery times. The rapidity and quality of recovery after sevoflurane anesthesia are as good or better than other available agents. Clinically more important are the new inhalation induction options possible with sevoflurane. These include vital capacity induction of general anesthesia in adult patients, intubation without neuromuscular blocking drugs, and management of selected patients with difficult airways. Anesthesia by facemask or LMA is easily performed without agent-related irritative side effects. The cost of induction with sevoflurane is significantly less than the standard agent propofol, and is even less when sevoflurane is used for both induction and intubation. The costs of maintenance with sevoflurane are more than isoflurane but less than propofol, and can be reduced to low money amounts by the use of N2O and low fresh gas flows, as well as elimination of the anesthetic adjuvant drugs. These new, cost effective anesthetic techniques are useful additions to the spectrum of anesthetic choices for ambulatory surgery. PMID- 9363281 TI - An attempt to withdraw coverage by the insurance company in the event of gross negligence. Costs totalling US $ 4.5 million. AB - In its judgement of 11 June 1993, the Court of Appeal of Brussels upheld the personal liability of a trainee and the in solidum liability of the hospital in a case where an erroneous spinal injection caused permanent paraplegia and incontinence. Although the attempt of withdrawal coverage by the insurance company on base of the concept of gross negligence, did not succeed in this case, it is clear that under the new insurance law of 25 June 1992, several risks will not be covered by the insurance companies in the future. The exemplary list of gross negligence cases, which may be used by the insurance companies, involves predominantly anesthesiology practice. The coverage of several insurance contracts exclude e.g., damages resulting from simultaneous anesthesia, or from the absence of an anesthesiologist during the full course of the surgery and damages resulting from anesthesia in the absence of necessary monitoring and reanimation equipment. PMID- 9363282 TI - Historical note. PMID- 9363283 TI - Dorothy and The Wizard. Intergenerational issues in mental health and aging. PMID- 9363284 TI - "Mixed dementia": adequate or antiquated? A critical review. AB - Despite its importance and widespread usage, the term mixed dementia, referring to the coexistence of Alzheimer's disease (AD) and vascular dementia (VsD), has been ill-defined and poorly conceptualized. The authors review the use of the term mixed dementia in neuropathological and clinical research. As a result of recent developments in the categorization of dementias, they recommend discarding the term mixed dementia in favor of a more precise terminology based on AD and VsD concurrently meeting established criteria for each diagnosis. PMID- 9363285 TI - Clinically oriented basic science. Emerging opportunities for research in late life mental disorders. PMID- 9363286 TI - Survivors. A review of the late-life effects of prior psychological trauma. AB - The author reviews the literature on the epidemiology, symptom picture, and treatment of elderly patients who have encountered serious psychological trauma earlier in life. Data are predominantly derived from studies of aging Holocaust survivors and combat veterans from World War II, the Korean Conflict, and Vietnam, Survivor syndromes persist into old age, but patterns of expression vary. Holocaust survivors appear to have adapted well to instrumental aspects of life, whereas combat warriors may show less functional life-adaptation. Persisting symptoms in all groups include marked disruptions of sleep and dreaming, intrusive memories, impairment of trust, avoidance of stressors, and heightened vulnerability to various types of age-associated retraumatization. There is a deficiency of controlled treatment studies of traumatized elderly patients, but successful group, individual, and family clinical interventions have been described. PMID- 9363287 TI - Nondementia nonpraecox dementia praecox? Late-onset schizophrenia. AB - Schizophrenia has traditionally been viewed as a psychotic disorder with onset in adolescence or early adulthood and a deteriorating course. Over the past decade, the authors have been studying patients meeting DSM-III-R as well as specified research criteria for late-onset schizophrenia (onset after age 45) and several comparison groups with psychiatric, neurologic, neuropsychologic, brain-imaging, psychophysiological, and psychosocial assessments. Results to date suggest a number of similarities and differences between late-onset schizophrenia and comparison groups of other older patients with psychoses (including earlier-onset schizophrenia). Later-onset schizophrenia is probably a neurobiologically distinct subtype of schizophrenia. Differential involvement of cortico-striato pallido-thalamic circuitry may explain differences in age at onset. The authors propose a new conceptual model for level of functioning at different stages of life in late-onset schizophrenia. PMID- 9363288 TI - Minor physical anomalies in older patients with late-onset schizophrenia, early onset schizophrenia, depression, and Alzheimer's disease. AB - The authors assessed five groups of older subjects (age > 45) for evidence of minor physical anomalies. The groups were patients with early-onset schizophrenia (onset at age < 45; n = 15), late-onset schizophrenia (onset at age > 45; n = 8), Alzheimer's disease (AD; n = 11), and unipolar depression (n = 11), and normal comparison (NC) subjects (n = 15). Patients with late- and early-onset schizophrenia, and unipolar depression were found to have significantly more anomalies than NC subjects. Patients with AD did not have significantly more anomalies than NC subjects, although the patients with AD were significantly older than the NC subjects. The authors discuss implications of these findings on the pathophysiology of schizophrenia. PMID- 9363289 TI - Naltrexone as an adjunctive treatment for older patients with alcohol dependence. AB - The authors examined the efficacy of naltrexone as an adjunctive treatment for alcohol dependence in older adults. Forty-four veterans over 50 years of age were enrolled in a 12-week, double-blind, placebo-controlled efficacy study of naltrexone (the equivalent of 50 mg per day). There were no differences in the frequency of any self-reported adverse effects or in liver enzyme values between the placebo- and naltrexone-treated groups. There were no differences between the treatment groups in the number of subjects remaining abstinent or in the number of subjects who relapsed. However, all placebo-treated subjects relapsed after sampling alcohol, whereas only three of six naltrexone-treated subjects met relapse criteria after alcohol exposure (P = 0.024). The authors conclude that naltrexone was well tolerated and efficacious in preventing relapse in subjects who drank. PMID- 9363290 TI - Comparison of cultural bias in two cognitive screening instruments in elderly Hispanic patients in New Mexico. AB - The authors compared the Mini-Mental State Examination (MMSE) and the Fuld Object Memory Exam (FULD) in a Hispanic non-immigrant population in New Mexico. Results demonstrated that performance on the MMSE was affected by lower education and income levels. Performance on the FULD was not affected by these variables. Among persons with limited education and lower income, the FULD may provide a better means of screening for cognitive deficit than measures such as the MMSE. PMID- 9363292 TI - An open trial of valproate for agitation in geriatric neuropsychiatric disorders. AB - The authors assessed the efficacy, tolerability and safety of open valproate administration in a group of elderly patients with agitation and neuropsychiatric disorders (N = 13), most of whom had dementia (n = 12). Dosing was individualized according to the response of target symptoms and side effects. Clinical Global Impression of Change (vs. baseline) measured efficacy. This open treatment suggested that valproate reduced agitated behaviors in some patients, and is well tolerated; thus, results warrant a larger, randomized, placebo-controlled study. PMID- 9363291 TI - The association between Apo E genotype and depressive symptoms in elderly African American subjects. AB - In this study of 138 elderly subjects (112 without and 26 with dementia) obtained from a community sample of elderly African-American subjects, there were no significant differences in mean Geriatric Depression Scale scores by Apo E epsilon 4 status for dementia or nondementia subjects. Three subjects received a diagnosis of major depressive disorder. None of these subjects were Apo E epsilon 4-positive. These results do not support an association between depressive symptoms and Apo E allele status in this elderly African-American population. PMID- 9363293 TI - Ninety-three--and washing. PMID- 9363294 TI - n-3 polyunsaturated fatty acids and cytokine production in health and disease. AB - Arachidonic-acid-derived eicosanoids modulate the production of pro-inflammatory and immunoregulatory cytokines. Overproduction of these cytokines is associated with both septic shock and chronic inflammatory diseases. The n-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid, which are found in fish oils, suppress the production of arachidonic-acid-derived eicosanoids and EPA is a substrate for the synthesis of an alternative family of eicosanoids. Thus, dietary fats which are rich in n-3 PUFAs have the potential to alter cytokine production. Animal studies have provided a great deal of evidence that feeding plant or fish oils rich in n-3 PUFAs does alter the ex vivo production of tumour necrosis factor (TNF), interleukin 1 (IL-1), IL-6 and IL-2, but many contradictory observations have been made; it is most likely that the discrepancies in the literature result from differences in the cell types and experimental protocols used. Human studies provide more consistent data: several studies have shown that supplementation of the diet of healthy volunteers results in reduced ex vivo production of IL-1, IL-6, TNF and IL-2 by peripheral blood mononuclear cells. Similar findings have been made in patients with rheumatoid arthritis and multiple sclerosis. Animal studies indicate that dietary fish oil reduces the response to endotoxin and to pro-inflammatory cytokines, resulting in increased survival; such diets have been beneficial in some models of bacterial challenge, chronic inflammation and auto-immunity. These beneficial effects of dietary n-3 PUFAs may be of use as a therapy for acute and chronic inflammation and for disorders which involve an inappropriately activated immune response. PMID- 9363295 TI - Docosahexaenoic and arachidonic acid absorption in preterm infants fed LCP-free or LCP-supplemented formula in comparison to infants fed fortified breast milk. AB - The absorption of long-chain polyunsaturated fatty acids (LCP) with particular respect to docosahexaenoic (DHA) and arachidonic acid (AA) has been studied in 39 very-low-birth-weight infants appropriate for gestational age after a 10-day feeding period. The infants were fed either a LCP-supplemented formula (n = 11), or a LCP-free formula (n = 11) or breast milk fortified with protein and carbohydrates to have similar protein and energy intakes as in the formula-fed infants (n = 17). Total fat content and fatty acid profile were measured in the human milk, the two formulas, and in the stool samples. After a 10-day feeding period, the fecal excretions of total fat, DHA and AA were measured during a 3 day balance period. The total fat apparent absorption rates were similar in all groups (84.1, 82.1 and 80.6% of intake, respectively). The DHA and AA intakes were significantly (p < 0.01) higher in the group fed the fortified breast milk than in the group fed the LCP-supplemented formula (DHA: 75.5 +/- 12.4 vs. 50.2 +/- 4.2 mg/72 h; AA: 45.5 +/- 5.8 vs. 30.2 +/- 2.7 mg/72 h). There was a tendency for lower apparent absorption rates for both LCPs studied in the group fed fortified breast milk when compared to the group fed LCP-supplemented formula (AA: 70.6 +/- 10.9 vs. 73.0 +/- 8.7% of intake, DHA: 69.0 +/- 10.6 vs. 74.2 +/- 9.5% of intakes, but the differences were not significant. As consequence of the different intakes, the net absorption of the two studied LCP fatty acids were significantly (p < 0.01) higher in the breast milk group than in the group fed the LCP-supplemented formula (DHA: 52.6 +/- 6.1 vs. 36.8 +/- 4.5 mg/72 h; AA: 31.4 +/- 3.1 vs. 22.4 +/- 2.3 mg/72 h). The data demonstrate that DHA and AA are absorbed from the studied LCP-supplemented formula at least as effectively as from human milk. The net absorption of these LCP depend on the amount of dietary intake, and seems to be influenced by the dietary LCP source. PMID- 9363296 TI - Fasting during Ramadan induces a marked increase in high-density lipoprotein cholesterol and decrease in low-density lipoprotein cholesterol. AB - We demonstrated for the first time in a Moroccan population that fasting during Ramadan, the ninth lunar month of the Muslims' year, affected lipid and lipoprotein metabolism in a group of 32 healthy adult male volunteers. This investigation was conducted to study the changes in serum total cholesterol, triglycerides, cholesterol in high-density lipoprotein (HDL) and low-density lipoprotein (LDL), glucose, and body weight during Ramadan. The results showed a significant decrease (7.9%, p < 0.001) in serum total cholesterol concentration during Ramadan as compared with the prefasting period. Also, we obtained a significant decrease of serum triglyceride concentration (30%, p < 0.001) during Ramadan fasting as compared to the period before Ramadan. The reduction of both serum triglycerides and total cholesterol was maintained 1 month after Ramadan. By the end of Ramadan, serum HDL cholesterol had markedly increased (14.3%, p < 0.001) and remained elevated 1 month after Ramadan in contrast to LDL cholesterol which showed a significant decrease (11.7%, p < 0.0001) also maintained 1 month after Ramadan. Mean body weight declined by 2.6% (p < 0.01) on day 29 of Ramadan, whereas during Ramadan, the diet pattern used by our subjects showed an increase of total energy intake due to carbohydrates (+ 1.4% of total energy), proteins (+ 0.4% of total energy) but not fat (-0.7% of total energy) compared to a usual diet used throughout the rest of the year. Moreover, the fat diet is high in monounsaturated (p < 0.05) and polyunsaturated fatty acid in contrast to saturated fatty acid which significantly (p < 0.05) decreased during Ramadan. These findings suggest that feeding behavior that occurs during Ramadan beneficially affects plasma lipids and lipoproteins. PMID- 9363297 TI - Pregnancy-related changes in fat mass and total DDT in breast milk and maternal adipose tissue. AB - BACKGROUND: Changes in body fat mass during pregnancy and its effects on total DDT concentration i.e. the, sum of pp'-DDT (pp'-dichlorodiphenyltrichloroethane), and pp'-DDE (pp'-dichlorophenyldichloroethylene), in maternal milk and abdominal fat were studied in humans. METHODS: Forty mothers that delivered by Caesarean section and chose to breast feed consented in providing samples (abdominal fat and breast milk) for determination of organochlorine pesticides. Constitutional variables, such as the number of children, and estimators of body fat mass, based on height and body weight (before and after pregnancy), were measured. RESULTS: Body mass index before and after pregnancy, as well as percent change in body weight, showed no significant difference in total DDT concentration in abdominal fat or breast milk. The only variable to significantly affect either body load of pesticides (abdominal fat) or its excretion (milk fat) was the number of children (p = 0.0117 and p = 0.0324, respectively). Correlation coefficients between DDT (in adipose tissue and milk fat) and variables related to body fatness (body mass index) were low and not significant. However, a close relationship was found between total DDT in adipose tissue and milk fat (r = 0.709; p = 0.0001). PMID- 9363298 TI - Effects of pectin on jejunal and ileal morphology and ultrastructure in adult mice. AB - The effects of pectin on jejunal and ileal morphology and ultrastructure were studied using adult male mice fed a semisynthetic diet containing 8% (w/w) cellulose or pectin for 30 days. No significant differences in the jejunal villus height between the 2 groups were found, but the jejunal crypt depth, and both the ileal villus height and crypt depth of the mice fed the pectin diet were significantly greater than those of the mice fed the cellulose diet. There were evident ultrastructural differences in the jejunal absorptive cells between 2 dietary groups: numerous intercellular spaces were observed in the jejunal absorptive cells of the mice fed the pectin diet, but not the cellulose diet. Moreover, the ileal absorptive cells of the mice fed the pectin diet contained numerous peroxisomes, whereas there were few in these cells of mice fed the cellulose diet. The functional characteristics of the ileum of the mice fed the pectin diet might be different from those fed the cellulose diet. PMID- 9363299 TI - Dietary fat quantity and composition induce changes in proliferation and membrane lipids in rat colon cells. AB - We have previously observed changes in colon cell proliferation in growing rats fed different levels of dietary fat as beef tallow or corn oil. Here we measured cellular proliferation at 18 and 30 weeks in the colon of rats fed beef tallow or corn oil and treated with the chemical carcinogen azoxymethane. Additionally, we assessed colon cell membrane lipid composition after 18 weeks on the defined diets and tumor incidence at 30 weeks. Dietary fat type and quantity significantly affected colon cell proliferation. Membrane phospholipids and free fatty acids were significantly affected by fat type. Tumor incidence was not affected by diet type. We conclude that dietary fat induces changes in cell membrane lipid composition and proliferation in the colon and these changes may be related to the development of tumors. PMID- 9363300 TI - Intimal hyperplasia following thrombectomy versus thrombolysis in occluded vein grafts. AB - Although the histologic effects of balloon catheter thromboembolectomy in arteries are well described, little is known about its effects on arterialized vein grafts. A chronic canine model was used to compare the intimal hyperplasia that develops following balloon catheter thrombectomy versus thrombolytic therapy when each treatment was used to open experimentally occluded reversed autogenous vein grafts. Eleven of 12 dogs survived to the time of graft thrombosis and treatment. Ten grafts in one group of animals were treated with shear force controlled balloon catheter thrombectomy, and eleven grafts in another group of animals were treated with infusion of urokinase (average 355, 833 IU/graft). Explantation and histologic evaluation was performed 5 weeks after treatment. Data were evaluated at comparable anatomic locations. These studies demonstrated the development of intimal hyperplasia in both groups with no statistically significant differences in the intimal thickening between the two treatment groups. It is hypothesized that vessel wall damage occurs at the time of thrombosis with the adherence of thrombus to the wall, and that this may be as important in producing intimal hyperplasia as the effects of carefully performed balloon thrombectomy or lytic therapy. PMID- 9363301 TI - Intraarterial urokinase for acute native arterial occlusion of the limbs. AB - Since 1988, 49 limbs of 47 patients underwent intraarterial urokinase infusion for acute native artery occlusion. The time from the onset of ischemic symptoms ranged from 1 to 45 days (mean = 17.5). The arterial sectors involved were femoropopliteal in 32 cases, followed by aortoiliac in 13 cases, distal in three cases, and subclavian in one case. Treatment consisted of placing a catheter in the clot and the infusion of 4400 U/kg in 20', followed by a series of 4400 U/kg weight/hour during 6 hours. Clinical evaluation, hemodynamic and coagulation parameters, and angiographical changes were assessed periodically. Infusion time ranged from 6 to 24 hours (mean = 13.2 hours). Improvement of ischemic was achieved in 43 (87.75%) patients. In five patients (12.25%) there was no improvement. Total immediate lysis was achieved in 35 cases (71.5%), and among them, 13 patients (26%) required no associated treatment, 16 (48%) underwent PTA, and four (12%) had surgery of underlying peripheral aneurysms revealed after thrombolysis. Partial lysis was achieved in 13 cases (26.5%), that was enough in four of them, but the remaining nine required further treatment (four PTA, and five arterial surgery). In one case no lysis was achieved, and arterial surgery was carried out. No mortality was recorded, and major complications included one upper gastrointestinal bleeding, and one cerebral hematoma. Late follow-up of successfully treated patients who did not require further surgery shows a cumulative patency rate of 81% at 24 months. PMID- 9363302 TI - Should balloon angioplasty and stents have any role in operative intervention for lower extremity ischemia? AB - Balloon angioplasty has been combined with open vascular surgery to treat lower extremity ischemia due to multilevel occlusive disease. The purposes of this study were: (1) to compare staged and simultaneous approaches to determine the optimal method for combining endovascular and open techniques and; (2) to assess the role of stents in intraoperative balloon angioplasty. Among 274 patients undergoing lower extremity revascularization over 30 months, 38 (13.9%) required a combination of endovascular and open techniques; 17 were staged (endovascular followed at an interval by distal open surgery) and 21 were simultaneous (intraoperative balloon angioplasty with or without stent placement at the time of open surgery). Groups were similar with respect to demographics, lesions treated with endovascular intervention, incidence and location of stent placement, and results of surgery. Additional operating time required for intraoperative endovascular intervention was 41.0 +/- 30.7 min., fluoroscopic time was 3.9 +/- 2.4 min. and contrast administered was 58.8 +/- 28.1 ml. There was no perioperative mortality. Length of stay was longer in the staged than in the simultaneous group (p < 0.01). Cumulative combined primary patency at 1 year by life-table methods was 82 +/- 10% in the staged group and 83 +/- 9% in the simultaneous group (p = 0.79). Mean follow-up was 13 +/- 6 months. There is a role for balloon angioplasty and stent placement in operative revascularization of ischemic limbs in selected patients: patency was similar to that produced with the staged approach while the length of stay was shorter. Intraoperative balloon angioplasty is safe and effective and stents permit a measure of control in assuring an optimal intraoperative postangioplasty result. PMID- 9363303 TI - Inhibition of intimal hyperplasia by an antisense oligonucleotide of farnesyl transferase delivered endoluminally during iliac angioplasty in a rabbit model. AB - The major complication of vascular recanalization is intimal hyperplasia which is due mainly to proliferation and migration of smooth muscle cells (SMC). Activation of SMC results from stimulation of protooncogens (c-myb, c-myc, c-fos) by growth factors induced by activated ras-proteins. Ras-proteins become activated after receiving a farnesyl group in a reaction catalyzed by famesyl transferase. The purpose of this study was to test the effectiveness in preventing intimal hyperplasia of an antisense oligonucleotide of the alpha subunit of farnesyl-transferase delivered endoluminally during angioplasty of the common iliac artery in rabbit model. Twenty-one male New Zealand rabbits with a mean weight of 3.3 kg fed a high cholesterol diet underwent bilateral angioplasty of the common iliac artery using hydrogel-coated balloon catheters. On the right side three types of treatment were randomly performed by adding one of the following three oligonucleotides to the hydrogel precoating:antisense oligonucleotide of farnesyl transferase (n = 7), mismatch oligonucleotide (n = 7), and scramble oligonucleotide (n = 7). On the left side hydrogel was used with saline so that each animal served as its own control. Animals were killed 6 weeks after angioplasty and arteries were studied. The thickness and mean surface of the neointima (MTI and MSI) and the ratio (R) of the neointima to neointima + media were calculated. In the scramble and mismatch groups there was no difference between the treated and control arteries with regard to MTI, MSI, or R. In the antisense group mean all three values were significantly lower on the treated side than the control side (EMI: p < 0.02, SMI: p < 0.02, and R: p < 0.01). Treated arteries in the antisense group presented significantly lower EMI (p < 0.02), SMI (p < 0.02), and R (p < 0.01) than treated arteries in the other groups whereas the thickness and mean surface of the media were comparable. Endoluminal administration of an antisense oligonucleotide against the alpha subunit of farneysyl transferase inhibited intimal hyperplasia in our model. PMID- 9363304 TI - Albumin-impregnated prosthetic graft for infrarenal aortic replacement: effects on the incidence and volume of perioperative blood transfusion. AB - We retrospectively reviewed 290 cases in which an albumin-impregnated polyester prosthetic graft was used for surgical management of aortic bifurcation disease between November 1987 and December 1990. The purpose of this review was to determine the incidence and volume of blood transfusion and to evaluate the rate of patency and the incidence of infection achieved using this type of prosthesis. The indication for surgery was abdominal aortic aneurysm (AAA) in 218 cases (190 elective procedures and 28 emergency procedures) and occlusive disease of the aortic bifurcation (ODAB) in 72 cases. Mean follow-up was 25.5 +/- 13.4 months (range: 1 and 50 months). The incidence of blood transfusion for elective AAA and ODAB surgery was 30.2% and 32.3% intraoperatively, 21.3% and 12.9% postoperatively, and 40.4% and 42.6% overall. The mean number of red cell packs transfused for elective AAA and ODAB surgery was respectively 1 and 0.8 intraoperatively, 0.4 and 0.6 postoperatively, and 1.4 and 1 overall. No immediate or late graft infection prosthesis was observed in any patient in this series. Primary and secondary patency was 95.5% and 97.5% at 6 months with no graft thrombosis during further follow-up. The fact that use of an impregnated graft in management of aortic bifurcation disease was accompanied by a high incidence and volume of blood transfusion suggests that these grafts do not reduce perioperative blood loss. Use of an impregnated prosthesis had no effect on the rate of patency and the incidence infection. PMID- 9363305 TI - Prospective randomized study of carbon-impregnated polytetrafluoroethylene grafts for below-knee popliteal and distal bypass: results at 2 years. The Association Universitaire de Recherche en Chirurgie. AB - The purpose of this prospective randomized multicenter study is to compare patency for a new carbon-impregnated polytetrafluoroethylene (PTFE) graft and standard PTFE grafts. One hundred and sixty patients presenting severe chronic ischemia of the lower extremity were recruited at 17 centers of the French Association Universitaire de Recherche en Chirurgie. Eighty-one carbon impregnated graft and 79 standard grafts were implanted. The procedure consisted of below-knee femoropopliteal bypass in 83 cases and femorodistal bypass in 77 cases. The minimum duration of the follow-up period was 2 years. Twenty-four patients died during the study. The actuarial primary patency rate, actuarial secondary patency rate, and limb salvage rate were 45%, 53%, and 57% respectively in the carbon-impregnated PTFE group and 35%, 36%, and 47% respectively in the standard PTFE group. The carbon-impregnated graft appeared to achieve better patency than the standard graft but the difference was not statistically significant. Since there was no difference up to 12 months, the study will be continued to determine if further follow-up confirms these findings. In this study we also assessed factors contributing to patency of below-knee prosthetic bypass grafts. Only two factors had a significant influence on patency, i.e., ankle/arm pressure difference greater than 0.25 as opposed to ankle/arm pressure difference less than 0.25 (p < 0.01) and below-knee femoropopliteal bypass as opposed to femorodistal bypass (p < 0.001). PMID- 9363306 TI - Early presence of endothelial-like cells on the flow surface of porous arterial prostheses implanted in the descending thoracic aorta of the dog. AB - The purpose of this study was to investigate early arterial graft healing and its sources in porous Dacron prostheses after very short implantation periods in the dog, using extensive histologic examination of serial sections. Preclotted Dacron prostheses 6 cm long and 8 mm in diameter were implanted in the descending thoracic aorta (DTA) of 14 dogs, and retrieved at 7 days (n = 6), 10 days (n = 4), and 14 days (n = 4). The flow surface was assessed for thrombus coverage, endothelial-like cell (ELC) coverage, and the number of microvessel ostia. Where an ELC island was identified under the stereomicroscope, full-wall longitudinal tissue samples were taken, and embedded in resin for light microscopy study of 6 microns, H&E-stained serial sections to determine general healing and interstitial tissue presence. If there was more than one ELC island, another full wall sample was taken and embedded in paraffin for staining with laminin, collagen IV, and smooth muscle alpha-actin antibodies, and PTAH. All grafts were patent with very little thrombus. Islands of endothelial-like cells were found for each time period, and on all 14-day grafts. Endothelial-like cell coverage was highest at 14 days. On 7- and 10-day grafts, cells proved to be endothelium were found in the middle of the flow surface, unconnected to either pannus or perigraft tissue ingrowth. Healing occurs as early as 7 days in porous knitted Dacron grafts. The source at periods earlier than 10 days appears to be cells from the blood stream. PMID- 9363307 TI - Coronary bypass in vascular patients: a relatively high-risk procedure. AB - A premise of cardiac risk stratification is that the added risk of coronary artery bypass grafting (CABG) is offset by the improved safety of subsequent vascular reconstruction (VR). We questioned if elective CABG is patients with severe peripheral vascular disease (PVD) is a relatively high-risk procedure. A cohort study of 680 elective CABG patients from January 1993 to December 1994 was performed using three mutually exclusive outcomes of complication-free survival, morbidity, and mortality. Patient characteristic, operative, and outcome data were prospectively collected. Retrospective review determined that 58 patients had either a standard indication for or a history of VR. Overall CABG mortality was 2.5%, with statistically similar but relatively higher rates for PVD as compared to non-PVD patients. In contrast, major morbidity occurred at rates 3.6 fold higher in PVD patients (39.7%) than in disease-free patients (16.7%) after adjustment for the effects of patient and operative variables (odds ratio [OR] 3.67, 95% confidence interval [CI] 1.93-6.99). CABG morbidity in the PVD patient was most likely in those patients with aortoiliac (OR 9.51, CI 3.20-28.27) and aortic aneurysmal (OR 5.24, CI 1.28-21.41) disease types. CABG in PVD patients is associated with significant major morbidity. Such morbidity may preclude or alter the timing of subsequent VR. PMID- 9363309 TI - Screening for major deep vein thrombosis in seriously injured patients: a prospective study. AB - The purpose of the study is to determine the prevalence of acute deep venous thrombosis (DVT) in severely injured trauma patients, to investigate the cost effectiveness of a noninvasive surveillance program, and to assess the merit of current methods of prophylaxis against DVT. One hundred and forty-eight patients (295 limbs) with a mean age of 36.5 years, mean trauma score of 13.3, mean injury severity score of 22.4 with predominantly blunt injuries (88.5%), were part of the study. The mean length of stay was 17.6 days. Venous duplex scans (VDS) were performed on inpatients on days 2-5, day 11, and day 30 following admission. Sequential compression device and/or subcutaneous heparin was used in 99% of patients with compliance being monitored by trauma nurse clinicians. A total of 272 VDS were performed with total charges of $111,520. DVT was found by VDS or venography in eight limbs (2.7%) of six patients (4%), our of the limbs being symptomatic. Two additional patients had pulmonary embolism, both with normal VDS. Routine serial VDS in severely injured patients who undergo aggressive prophylaxis against DVT is not cost effective and therefore not justified. PMID- 9363308 TI - The limits of generalized cardiac screening tests for predicting cardiac complications after infrainguinal arterial reconstruction. AB - We examined the relative efficacies of different cardiac screening strategies for infrainguinal arterial bypass. The outcomes of 205 elective leg bypass procedures over a 10-year period, including myocardial infarction (MI), total cardiac complications, and mortality were tallied. Clinical risk factors popularized by Goldman and Eagle, and the results of dipyridamole thallium myocardial imaging (DThal) were recorded. The overall mortality rate was 3.4%, with a 3.4% incidence of MI and a 5.4% total cardiac complication rate. Both abnormal DThal (p = 0.011) and Goldman class II-IV (p = 0.030) were significant predictors of MI and cardiac death, but both suffered from poor specificity and positive predictive value. Because logistic regression analysis identified a correlation between angina, CHF, and an abnormal DThal, a customized screening strategy was developed to include the presence of angina, CHF and an abnormal DThal. Eighty-eight percent of patients suffering MI or death met these criteria, while only 11% of the complication-free group did. This screening strategy provided a superior sensitivity of 88%, specificity of 89%, positive predictive value of 25%, and 99% negative predictive value. A customized screening strategy (angina, CHF, abnormal DThal), developed from a 10-year experience with a single patient group, provided better predictive accuracy than any generalized screening formula. PMID- 9363310 TI - Carotid artery pseudoaneurysm as a complication of ECMO. AB - Any pulsatile neck mass after extracorporeal membrane oxygenation (ECMO) must be viewed as a pseudoaneurysm of the carotid artery until proven otherwise. Prompt diagnosis is necessary utilizing ultrasound. Angiography may not be necessary. Carotid artery pseudoaneurysm requires urgent surgical intervention to prevent catastrophic hemorrhage. The utilization of cardiopulmonary bypass may facilitate safe repair. PMID- 9363311 TI - Mycotic aneurysm of the extracranial carotid artery: an uncommon complication of bacterial endocarditis. AB - This report describes a case involving mycotic aneurysm of the extracranial internal carotid artery occurring as a complication of staphylococcal endocarditis in a patient with systemic lupus erythematosus. Three main points are emphasized: (1) this complication occurred in an immunodepressed patient; (2) surgical treatment consisted of aneurysmorraphy using absorbable suture; (3) the outcome was successful with a follow-up of 24 months. PMID- 9363312 TI - Abdominal aortic aneurysm in a child with tuberous sclerosis. AB - Tuberous sclerosis is known to be associated with neurologic, renal and cardiac lesions. We report a case involving a child with tuberous sclerosis who developed infrarenal abdominal aortic aneurysm. Surgical therapy was successful. Although aortic aneurysm is uncommon in children with tuberous sclerosis, routine screening is necessary due to the high risk of death by rupture. Surgical treatment must be performed immediately. PMID- 9363313 TI - Sequential configuration for aorto-celiac-mesenteric bypass. PMID- 9363314 TI - Upper extremity revascularization proximal to the wrist. PMID- 9363315 TI - Effects of elements on blood pressure. AB - This article present a comprehensive review of all known elements involved in blood pressure control. Data source was by computerized literature searches. A total of 28 elements have been documented as being involved in blood pressure control. The individual elements react directly and indirectly in a variety of metabolic and structural activities known to participate in blood pressure regulation. Reports from both experimental animal and human subjects are presented. The role of certain elements in blood pressure control is controversial. Conversely, important established functions of dosage, absorption, storage, and excretion of individual elements are known and are described in relation to blood pressure control. Some elements are pressor, whereas others are depressor in action, and this article demonstrates the important role elements play in the control of blood pressure. PMID- 9363316 TI - Lead transport in IEC-6 intestinal epithelial cells. AB - This study evaluated the use of IEC-6 cells as a model for studying lead (Pb) transport by intestinal epithelial cells (IECs) and examined potential transport mechanisms for Pb uptake and extrusion. Pb accumulation in IEC-6 cells exposed to 5 and 10 microM Pb for up to 60 min was time- and dose-dependent. Reduction of incubation temperature significantly reduced the total cellular Pb content of IEC 6 cells. Simultaneous exposed of cells to zinc (Zn) and Pb resulted in decreased total cellular Pb contents compared to total cellular Pb contents of cells exposed to Pb only. IEC-6 cells treated with ouabain (1 mM) or sodium azide (1 mM) and 5 microM Pb accumulated more Pb than cells exposed to Pb only. Cells treated with p-chloromercuribenzensulfonic acid (50 microM), p chloromercuribenzoic acid (50 microM), or iodoacetimide (50 microM) accumulated less Pb than cells treated with Pb only. We conclude that Pb uptake by IEC-6 cells depends on the extracellular Pb concentration. Our data suggest that the mechanism of Pb uptake by IECs is complex, and that Pb transport in IEC-6 cells is time- and temperature-dependent, involves sulfhydryl groups, and is decreased by the presence of Zn. Extrusion of Pb is at least partially dependent on metabolic energy. PMID- 9363317 TI - Dietary nickel and folic acid interact to affect folate and methionine metabolism in the rat. AB - A previous experiment using rats indicated that dietary nickel (Ni), folic acid, and their interaction affected variables associated with one-carbon metabolism. That study used diets that produced only mild folate deficiency. Thus, an experiment was performed to determine the effect of a severe folate deficiency on nickel deprivation in rats. A 2 x 2 factorially arranged experiment used groups of six weanling Sprague-Dawley rats. Dietary variables were nickel, as NiCl2 6H2O, 0 or 1 microgram/g and folic acid, 0 or 4 mg/kg. All diets contained 10 g succinylsulfathiazole/kg to suppress microbial folate synthesis. The basal diet contained < 20 ng Ni/g. After 58 d, an interaction between nickel and folate affected the urinary excretion of formiminoglutamic acid (FIGLU) and the liver concentration of S-adenosylmethionine (SAM). Because of this, it is proposed that the physiological function of nickel is related to the common metabolism shared by SAM and FIGLU. Possibly the physiological function of nickel could be related to the tissue concentration of 5-methyltetrahydrofolate (MTHF) or tetrahydrofolate (THF). PMID- 9363318 TI - Adding zinc reduces bone strength of rats fed a low-calcium diet. AB - This experiment examined skeletal effects of moderate zinc (Zn) supplementation of a low-calcium diet. Male weanling rats were fed experimental diets for about 4 wk. One diet was adequate (control), whereas two others were calcium-deficient, but otherwise adequate. One of the low-calcium (Ca) diets was supplemented with Zn. Dimensions, weight, mineral content, and mechanical properties of femurs were measured. Ca deficiency reduced bone mineral content and strength markedly. Adding Zn to the low-Ca diet further reduced bone strength and elasticity, compared with the unsupplemented low-Ca diet. When the Ca intake is low, possible benefits of Zn supplements should be weighted against risk of deterioration of mechanical properties of bone. PMID- 9363319 TI - Bioavailability of selenium from veal, chicken, beef, pork, lamb, flounder, tuna, selenomethionine, and sodium selenite assessed in selenium-deficient rats. AB - The bioavailability of selenium (Se) from veal, chicken, beef, pork, lamb, flounder, tuna, selenomethionine (SeMet), and sodium selenite was assessed in Se deficient Fischer-344 rats. Se as veal, chicken, beef, pork, lamb, flounder, tuna, SeMet, and sodium selenite was added to torula yeast (TY) basal diets to comprise Se-inadequate (0.05 mg Se/kg) diets. Se as sodium selenite was added to a TY basal diet to comprise a Se-adequate (0.10 mg Se/kg), Se-control diet. The experimental diets were fed to weanling Fischer-344 rats that had been subjected to dietary Se depletion for 6 wk. After 9 wk of the dietary Se repletion, relative activity of liver glutathione peroxidase (GSHPx) from the different dietary groups compared with control rats (100%) was: flounder 106%, tuna 101%, pork 86%, sodium selenite 81%, SeMet 80%, beef 80%, chicken 77%, veal 77%, and lamb 58%. Se from flounder was the most efficient at restoring Se concentrations in the liver and skeletal muscle. Se from sodium selenite, SeMet, beef, veal, chicken, pork, lamb, and tuna was not dietarily sufficient to restore liver and muscle Se after 9 wk of recovery following a 6-wk period of Se depletion. PMID- 9363320 TI - Diffusibility of selenate, selenite, seleno-methionine, and seleno-cystine during simulated gastrointestinal digestion. AB - The present study was undertaken to evaluate the in vitro availability of chemically varying forms of selenium (Se), supplemented in cow's milk. Two inorganic (selenite and selenate) and two organic (seleno-methionine [Se-Met] and seleno-cystine [Se-Cys]) Se sources were evaluated. The in vitro availability was estimated by the diffusibility of Se during simulated gastrointestinal digestion. First, the diffusibility was compared after adding a constant amount of Se as either selenate, selenite, seleno-methionine, or Se-Cys in milk samples. Se-Met and selenate were found to be significantly more diffusible than seleno-cystine and selenite under the simulated gastrointestinal conditions. The tendency for superior in vitro availability of selenate and Se-Met compared to selenite and Se Cys was confirmed for a supplementation range of 5-40 ng/g of Se. This study suggests that the high diffusibility of selenate and Se-Met in a simulated gastrointestinal environment may contribute to their high absorption in vivo. PMID- 9363321 TI - The possible role of zinc and metallothionein in the liver on the therapeutic effect of IFN-alpha to hepatitis C patients. AB - We have studies zinc deficiency in hepatitis C patients (complete responder [CR] 22, nonresponder [NR] 25) with relation to the therapeutic effect of interferon alpha (IFN-alpha). Circadian variations in serum zinc levels were high in the morning (basal level) and then gradually decreased during the day in both chronic hepatitis C patients and healthy controls. Basal zinc levels in serum were significantly lower in chronic hepatitis C patients (73 +/- 3 micrograms/dL, n = 12) than in controls (93 +/- 5 micrograms/dL). An injection of 10 MU of IFN-alpha to hepatitis C patients augmented the serum zinc reductions, up to 40% in 8 h. Serum cortisol levels were significantly elevated 8 h (25.6 +/- 2.3 micrograms/dL) after IFN-alpha dose. Forty-seven chronic hepatitis C patients were treated with IFN-alpha for 24 wk, and serum zinc and copper levels were determined 12 and 24 wk during and after the completion of IFN-alpha therapy. Serum zinc levels and zinc/copper ratio were higher in CRs than in NRs to IFN therapy at each time-point. Hepatic metallothionein staining became prominent after IFN therapy in most of CRs, whereas it diminished NRs. These data suggest that nutritional status of zinc influences the effect of IFN on hepatitis C patients. PMID- 9363322 TI - Tissue platinum after clinical treatment with cisplatin or carboplatin in tumor bearing patients. AB - Tissue platinum (Pt) levels were measured in tumor-bearing patients treated with either cisplatin or carboplatin. Cisplatin was given by intra-arterial, intraperitoneal, and intravenous (iv) administrations. After death, vertebrae and intervertebral disks were removed from eight human subjects, and livers and kidneys were removed from the half of them. When cisplatin was administered intraperitoneally, Pt of the liver was higher than that of the kidney, and a high content of Pt was detected in the vertebra by comparing with the other administration methods. At the intra-arterial administration of cisplatin, Pt was mainly accumulated in the kidney. At the iv administration of cisplatin, a high level of Pt was found in the vertebra and intervertebral disk, especially at the highest value at 10.31 micrograms/g in the intervertebral disk of one case, whereas a low level of Pt was detected in the liver. On the contrary, it was found that the iv administration of carboplatin did not result in high accumulations of Pt in the liver, kidney, intervertebral disk, and vertebra. Therefore, Pt is accumulated in different organs, depending on the way cisplatin is administered, but Pt is accumulated least in them by the administration of carboplatin. PMID- 9363323 TI - Plasma glutathione peroxidase activity and selenium levels of newborns with jaundice. AB - The plasma glutathione peroxidase (GSH-Px) and selenium (Se) levels were determined in 31 newborns affected by jaundice (NWJ). The GSH-Px levels of both full-term and premature newborns exhibiting jaundice and having a birthweight lower than 2000 g were significantly low (p < 0.05) when compared to controls. No significant differences were found in the corresponding Se levels, which were similar in all groups and independent of the pregnancy period and birthweight. PMID- 9363324 TI - Effects of lithium deficiency in some insulin-sensitive tissues of diabetic Chinese hamsters. AB - In this work, we report the effect of low-dose lithium carbonate on blood glucose levels and tissue lithium content in hereditary spontaneous diabetic Chinese hamsters (HSDCHs). Hepatic lithium levels are significantly lower in diabetic hamsters when compared to healthy controls: 2.05 +/- 0.26 and 3.04 +/- 0.11 micrograms/g, respectively. The same trend was observed in kidney and muscle: 18.26 +/- 0.24 vs 20.23 +/- 1.10 micrograms/g and 4.66 +/- 0.17 vs 5.95 +/- 0.67 micrograms/g, respectively. The significance level was p < 0.05 in all cases. Supplementation with lithium carbonate eliminated tissue lithium deficiency, and had a normalizing effect on blood glucose and glycosylated serum protein levels. The insulin sensitivity index (ISI) increased, thus reducing insulin resistance. Our results suggest that lithium deficiency in certain insulin-sensitive tissues may be associated with blood glucose imbalance resulting from insulin resistance. PMID- 9363325 TI - Daily magnesium supplementation on serum and urinary magnesium changes in rats during prolonged restriction of motor activity. AB - The objective of this investigation was to determine whether a plentiful magnesium (Mg2+) supplementation might be used to normalize or prevent Mg deficiency. This is manifested by increased rather than decreased serum Mg2+ concentration as is observed during prolonged hospitalization, which is developed during prolonged hypokinesia (HK) (decreased motor activity). Eighty male Wistar rats with an initial body weight of 370-390 g were used to perform the studies: They were equally divided into four groups: 1. Unsupplemented control animals (UCA); 2. Supplemented control animals (SCA); 3. Unsupplemented hypokinetic animals (UHA); and 4. Supplemented hypokinetic animals (SHA). For the simulation of the hypokinetic effect, the hypokinetic animals were kept in small individual cages made of wood which restricted their movements in all directions without hindering food and water intake. The control and hypokinetic supplemental animals receive 0.9 mg/mL Mg sulfate daily with their drinking water. Prior to and during the experimental period, urinary excretions of Mg, calcium, and phosphate along with their concentrations in serum, water intake, and urine excretion, and body weight were determined in the control and hypokinetic animals. In the supplemental and unsupplemental hypokinetic rats, urinary excretions and serum concentrations of electrolytes increased significantly, whereas serum concentration and urinary excretion thereof remained unchanged in the supplemented and unsupplemented control animals. It was concluded that a daily intake of large amounts of Mg supplementation cannot be used to prevent or normalize Mg deficiency in rats during prolonged exposure to HK. PMID- 9363326 TI - Serum and hair zinc levels in epileptic children taking valproic acid. AB - This study was performed to investigate the serum and hair zinc levels in patients epilepsy diagnoses who were intended to be put on valproic acid (VA) monotherapy and had never ingested antiepileptics before. A total of 16 patients having normal growth, development and nutrition was selected as Group 1, and Group 2 was made up of 10 patients who had received VA monotherapy for 2 yrs or more and had normal growth, development, and nutrition characteristics. A control group (Group 3) was formed of 15 subjects who applied to the hospital for upper respiratory tract disorders. Serum and hair samples were taken for zinc assays from the Group 1 patients on the d 0, 15, 30, 45, 60, 75, and 180. Groups 2 and 3 were sampled only once, and zinc levels were determined. We found that both serum and hair zinc levels in Group 1 were higher than those of Group 2 and control group before the beginning of VA therapy, but they returned to normal during VA treatment. There was no zinc deficiency, and zinc replacement treatment may therefore be considered as unnecessary. PMID- 9363327 TI - Serum selenium concentration of a healthy northwest Spanish population. AB - Selenium (Se) is an essential element, cofactor for glutathione peroxidase (GSHPx) activity, whose deficiency may induce modifications in the cellular antioxidative status and induce the appearance of different diseases. Current views suggest that a serum Se concentration inferior to 45 micrograms/L may correlate with an increased risk of coronary hearth diseases, coronary atherosclerosis and cancer. Since the Se concentration in human blood varies between geographical areas, we initiated a study to evaluate the Se status in the general healthy population of Barcelona. Serum Se concentration was investigated in a random sample of 150 subjects (age range 18-70 yr) by graphite furnace atomic spectrometry (FLAAS). L'vov platform, Zeeman background correction, and other specifications of stabilized temperature platform furnace (STPF) concept were followed. The results show that in the general population of Barcelona, Se serum concentration ranges between 60 and 106 micrograms/L (X = 80.7 +/- 10 micrograms/L). These values can be considered within the safe limits, since no subject was found with a concentration lower than the threshold of 45 micrograms/L. PMID- 9363329 TI - Antioxidant enzymes and trace elements in hemodialyzed patients. AB - Antioxidant enzymes together with trace elements in 26 patients with chronic renal failure treated with hemodialysis and 25 healthy subjects were investigated. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSHPx) in plasma and erythrocytes were examined immediately before and after hemodialysis. The results are summarized as follows: 1. A significant decrease in plasma SOD, CAT, and GSHPx and erythrocyte GSHPx were found in patients before hemodialysis. 2. Erythrocyte CAT and GSHPx were significantly lower in the patients after hemodialysis than in the controls. 3. Plasma GSHPx was significantly higher after a single hemodialysis than before hemodialysis. 4. A good correlation between erythrocyte SOD and copper (Cu) in patients before hemodialysis was found. 5. A good correlation of GSHPx in erythrocytes and plasma was found before hemodialysis, whereas an even better correlation was found after hemodialysis. 6. Abnormalities of trace elements were found in hemodialyzed patients. 7. There is indirect evidence for increased oxidizing stress in uremic patients with hemodialysis. Dialysis treatment may improve some abnormalities (e.g., Hb, P), but may also induce some deleterious effects of free radicals or lipid peroxidation. PMID- 9363328 TI - Adding Zn2+ induces DNA fragmentation and cell condensation in cultured human Chang liver cells. AB - Zinc (Zn) is a trace element in human cells and regarded as an essential nutrient with established deficiency states affecting multiple organs in the body. However, it has been reported that Zn uptake is associated with some serious harmful effects, such as inhibition of DNA synthesis and enhanced toxicity from reactive oxygen species. We have previously shown that in vivo administration of Zn2+ in C57/6J mice induces weight loss and massive hair loss where the normal course hair becomes replaced by fine vello hair, simulating the side effects from cancer chemotherapy where oxidative free radical damage is implicated in association with DNA fragmentation and programmed cell death (PCD). Here, in vitro flow cytometric studies on human Chang liver showed Zn2+ causing cell condensation with DNA fragmentation that occurred in a dose-dependent manner, an effect replicated by micrococcal nuclease digestion. Specific terminal deoxynucleotidyl transferase-(TdT) mediated labeling of 3'-OH ends of DNA nicks corroborated the flow cytometric profiles of propidium iodide-DNA binding where degradation of both 2 and 4 N genomic DNA resulted in a solitary 1N peak presentation. DNA degradation concomitant with cell condensation is seen as an established hallmark of PCD. We further showed that Zn2+ could enhance the generation of hydroxyl free radicals (OH.) by the transition metal vanadium. Glutathione, the cell's main reducing agent, underwent corresponding reduction. The results suggested that Zn supplementation could induce features resembling PCD. PMID- 9363330 TI - Effect of acute administration of mercuric chloride on the disposition of copper, zinc, and iron in the rat. AB - The present study was designed to investigate the effect of mercuric chloride administration on copper, zinc, and iron concentrations in the liver, kidney, lung, heart, spleen, and muscle of rats. The results showed that after dose and time exposure to mercuric chloride, the concentration of mercury in the six tissues was significantly elevated. Data showed that there were no interaction between mercury and tissue iron. There was a considerable elevation of the content of copper in the kidney and liver. The most significant changes in the copper concentration took place in the kidneys. About a twofold increase in the copper content of the kidney was noted after exposure to mercuric chloride (3 mg and 5 mg/kg). Only slight elevations in the copper content occurred in the liver especially in high dose and longer exposure time. In the remaining organs, the copper content was not changed significantly (p > 0.05). The most significant changes in the zinc concentration took place in liver, kidney, lung and heart (5 mg/kg). Marked changes in kidney zinc concentrations were observed at any of the specified doses. Zinc concentrations were significantly increased in kidney of rats sacrificed 9-48 h after s.c. injection of HgCl2 (5 mg/kg); in liver obtained from rats at 18, 24 or 48 h after injection; and in lung after 24 or 48 h of treatment. The heart and spleen zinc concentrations were elevated at 24 and 48 h after injection of HgCl2 (5 mg/kg), respectively. The results of this study implicate that effects on copper and zinc concentrations of the target tissues of mercury may play an important role in the pathogenesis of acute mercuric chloride intoxication. PMID- 9363331 TI - Elastic properties of human cortical and trabecular lamellar bone measured by nanoindentation. AB - An experimental investigation was undertaken to measure the intrinsic elastic properties of several of the microstructural components of human vertebral trabecular bone and tibial cortical bone by the nanoindentation method. Specimens from two thoracic vertebrae (T-12) and two tibiae were obtained from frozen, unembalmed human male cadavers aged 57 and 61 years. After drying and mounting in epoxy resin nanoindentation tests were conducted to measure Young's modulus and the hardness of individual trabeculae in the vertebrae and single osteons, and interstitial lamellae in the tibiae. Measurements on the vertebral trabeculae were made in the transverse direction, and the average Young's modulus was found to be 13.5 +/- 2.0 GPa. The tibial specimens were tested in the longitudinal direction, yielding moduli of 22.5 +/- 1.3 GPa for the osteons and 25.8 +/- 0.7 GPa for the interstitial lamellae. Analysis of variance showed that the differences in the measured moduli are statistically significant. Hardness differences among the various microstructural components were also observed. PMID- 9363332 TI - Structural characterization of pulsed laser-deposited hydroxyapatite film on titanium substrate. AB - Pure, crystalline hydroxyapatite (HA) films with thicknesses of roughly 10 microns have been deposited on titanium substrate using the pulsed laser deposition (PLD) technique. Experimental results indicate that the structure and properties of the PLD-HA films varied with deposition parameters. The PLD process used in the present study did not induce significant amounts of calcium phosphate phases other than apatite, or significant changes in the behaviour of hydroxyl or phosphate functional groups. Broad face scanning electron microscopy showed that HA coating was comprised of numerous essentially spheroidal-shaped particles of different sizes, while the lateral morphology indicated that columnar and dome shaped structures both existed in the film. Many pinholes and crevices observed on coating surfaces were linked to the original substrate surface crevices/craters. The adhesion strength of the coating, mostly in the range of 30 40 MPa, was found to be closely related to the fractography of the tested specimen. The fracture surfaces of specimens with higher bond strengths were usually accompanied by a higher degree of deformation and coating-substrate debonding, while the fracture of specimens with lower bond strengths occurred more frequently within HA coatings in a more brittle manner. The energy dispersive spectroscopy-determined Ca/P ratios of raw HA powder (1.78) and sintered HA target for PLD (1.79) were very close, indicating that the sintering process used in the present study essentially did not change the Ca/P ratio of HA. After the PLD process, the Ca/P ratio of the HA film increased to 1.99. Cross sectional scanning electron microscopy-energy dispersive spectroscopy point analysis indicated that the value of the Ca/P ratio was significantly higher in the region near the surface, particularly near the coating-substrate interface, than in the coating interior. PMID- 9363334 TI - Pulsed blue laser curing of hybrid composite resins. AB - Clinical performance of light-curing composite restorations is greatly influenced by the quality of the curing-light. Currently used photopolymerization units have some important drawbacks, such as decreasing light output with time and distance, which results in a relatively low degree of conversion and shallow depth of cure, particularly of darker shades. Experiments with continuous argon laser polymerization showed overheating of the composite sample, as well as increased shrinkage of the material. In this study a pulsed laser, set at 468 nm (the maximum of the camphorquinone absorption coefficient), with 20-ns pulse duration, repetition rate of 10 Hz and energy of 10 mJ per pulse, was used as a light source. The aim of the study was to evaluate the effect of polymerization of light and dark shades of three different hybrid composites cured by pulsed laser at the surface and at 3.0 mm depth. The degree of conversion was measured by Fourier transform infrared spectroscopy (FTIR). Applying pulsed blue laser, significantly better results were obtained for both shades compared to standard polymerization values. Very weak dependence of the degree of conversion, between the surface measurements and those at 3.0 mm, were observed in the case of pulsed laser polymerization due to the piercing nanopulses and the monochromatic light at 468 nm. PMID- 9363333 TI - Morphological evaluation of osteoblasts cultured on different calcium phosphate ceramics. AB - The objective of these investigations was to develop an in vitro test system for evaluating novel rapidly resorbable calcium phosphate ceramics of varying composition. Rat bone marrow cells were cultured on the disc-shaped test substrates for 14 days. Five calcium phosphates were examined: R1 CaNaPO4; R1/M2, composed of CaNaPO4 and MgNaPO4; R1/2, composed of CaNaPO4 and Mg2SiO4; R1 + 9% SiO2 consisting of CaNaPO4 and 9% SiO2 (wt%) and R17, Ca2KNa(PO4)2. Two studies were performed. In study I cultures were re-fed every two to three days. In study II the medium was changed daily, and calcium and phosphate concentrations of the medium were determined daily. Specimens were prepared for light microscopy and morphometric evaluation of the cell-covered substrate area, scanning electron microscopy and energy-dispersive X-ray analysis. With all materials tested except for R1/2, an increase of cellular growth was observed after changing the medium daily. Of the different calcium phosphate ceramics tested, R17 and R1/M2 facilitated osteoblast growth and elaboration of extracellular matrix to the highest degree. The inhibition of cell growth encountered with R1 in study I and R1/2 in both studies seemed to be related to a high phosphate-ion release from these materials. PMID- 9363335 TI - Hydrogels in endovascular embolization. VI. Toxicity tests of poly(2-hydroxyethyl methacrylate) particles on cell cultures. AB - Cytotoxicity of poly(2-hydroxyethyl methacrylate) [poly(HEMA)] hydrogel spherical particles, prepared by radical suspension polymerization and designed for endovascular occlusion, was studied in vitro on cell cultures. Testing methods included a direct contact test and extraction test. No inhibition of growth of cells surrounding the poly(HEMA) beads and a very low inhibition of cell viability, only in concentrated extracts in long-term contact, were observed. As a result, poly(HEMA) beads can be considered non-toxic. PMID- 9363336 TI - Development of methods for quantitative characterization of network morphology in pharmaceutical hydrogels. AB - We have employed a variety of methods which satisfactorily characterize the structure of polymeric hydrogels beyond the level of information provided by a single swelling test. We applied these techniques to gels which have potential for use as pharmaceuticals for the control of elevated phosphorous levels in patients suffering from chronic kidney failure. These 'fingerprinting' techniques help us understand the effects of various processing parameters on the gel morphology. Wide-angle X-ray diffraction experiments verified the structure and reproducibility across synthesized hydrogel batches. Measurements of the temperature- and frequency-dependent dielectric relaxation provided information on the network topology. Real-time diffusion experiments were performed using inductively coupled plasma atomic emission spectroscopy. Spherical gel particles (510 microns diameter) were used to measure equilibrium phosphate loadings of 4.5 mmoles g-1 from direct measurement of the decrease in phosphate ion concentration in aqueous solutions. PMID- 9363337 TI - Expression of intercellular adhesion molecule-1 on macrophages in vitro as a marker of activation. AB - Macrophage activation is a major component of wound healing. It also determines the extent of inflammatory reactions and the response of the body to implanted materials. We have previously shown, using an in vitro model, that the extent of spreading of macrophages on different materials is a marker of activation, and that a soluble inducer has a dose-response effect on the secretion of cytokines in the culture medium. This work investigates the expression of three different cell surface markers [macrophages MAC-1, MAC-3 and intercellular adhesion molecule-1 (ICAM-1)] on macrophages in vitro using confocal microscopy and shows that ICAM-1 is also a marker of macrophage activation in this model. We observed increased amounts of ICAM-1 on activated macrophages compared to unactivated macrophages, whereas MAC-1 and MAC-3 were either expressed constitutively or demonstrated no quantitative change in expression after activation under the same experimental conditions. We also tested the expression of ICAM-1 with various concentrations of soluble inducers (lipopolysaccharide, 0.001, 0.01, 0.1, 1 and 10 micrograms ml-1. S-27609, 0.1, 0.25, 0.5, 1, 2 and 3 micrograms ml-1 and on a sheet of polylactic acid alone or in combination with soluble inducers. All doses of soluble inducers induced the expression of ICAM-1 on cells grown in glass chamber slides. The induction was not dose related but seemed to work rather in an on-off manner. There was no effect of material on ICAM-1 expression on the cell surface when no soluble inducer was added. This was similar to cytokine secretion, which was not induced by our material alone. When either lipopolysaccharide or S-27609 was used in combination with the material, there was an increase in the average measured intensity of ICAM-1. In this in vitro model, ICAM-1 staining as measured by confocal microscopy is a marker for macrophage activation. Our results suggest that the extent of macrophage activation as measured by ICAM-1 and by cytokine secretion is more sensitive to soluble inducers than to the action of the flat sheet of polylactic acid. PMID- 9363338 TI - Mechanical performance of polyurethane ureteral stents in vitro and ex vivo. AB - A serious problem associated with the use of ureteral stents is fracture in situ. Following clinical observations of fracture of polyurethane stents in vivo, this study examined the mechanical properties of 17 polyurethane stents (double-J containing drainage holes) retrieved from patients over a 24-week period of insertion. In addition, stents were immersed in human and artificial urine in an in vitro model at 37 degrees C to determine their general propensity to fracture. Mechanical properties of ureteral stents were examined using the standard ASTM D 412 tensile test and by the novel application of dynamic mechanical analysis (DMA). The ultimate tensile strength and elongation at break (but not the Young's modulus) of unused polyurethane stent sections containing side-drainage holes were greater than stent sections devoid of side-drainage holes. No correlations were observed between increased or decreased Young's modulus, ultimate tensile strength or elongation at break of polyurethane stents and their time of immersion in either human urine or artificial urine in simulated upper urinary tract conditions of 37 degrees C and 5% CO2. Similarly, no correlations were observed between Young's modulus, ultimate tensile strength or elongation of polyurethane stents and stent dwell time in situ. DMA of retrieved stents revealed that their tan delta value and storage modulus did not differ significantly from unused stents following dwell times in situ of up to 24 weeks. No changes in the glass transition temperatures were observed in retrieved stents. Although patient variation was observed, the results indicate that the polyurethane stents examined in vitro and following removal from patients did not exhibit any greater propensity to fracture than their unused counterparts. Fracture of retrieved polyurethane stents, arising in vivo and also during subsequent tensile testing, was observed to occur along the drainage holes, suggesting that elimination of these holes will reduce the incidence of polyurethane ureteral stent fracture in use. PMID- 9363339 TI - Mightomycin. PMID- 9363340 TI - N-methyl-D-aspartate-induced excitotoxicity causes myopia in hatched chicks. AB - OBJECTIVE: To characterize the effect of the amacrine cell-selective toxin N methyl-D-aspartate (NMDA) on ocular growth in chicks. DESIGN: Single injections of NMDA in doses ranging from 20 to 2000 nmol in 20 microL of sterile saline were made into the vitreous chamber of one eye of 7-day-old white leghorn chicks (six chicks per group); the contralateral (control) eye was injected with saline. Six NMDA-treated eyes were also deprived of form vision by applying a translucent goggle 7 days after treatment, to determine whether myopia could still be induced or enhanced in NMDA-treated eyes. OUTCOME MEASURES: Axial length, equatorial diameter and refractive error, measured immediately after and 7, 14, 21, 28 and 35 days after treatment. RESULTS: NMDA-treated eyes became myopic within 7 days of treatment and remained so until at least 35 days after treatment. During this time the eyes continued to grow but could not be induced to become more myopic by depriving them of patterned images. The half-maximal effective dose of NMDA was calculated to be 670 nmol, 7 days after treatment. CONCLUSIONS: NMDA-induced excitotoxicity destroys retinal pathways by which patterned visual stimuli restrain ocular growth in the chick. PMID- 9363341 TI - Immunohistochemical expression of S-100 beta in choroidal melanomas. AB - OBJECTIVE: To investigate the expressivity of S-100 beta antibodies in choroidal melanomas and to compare it with that of S-100 protein and HMB-45. DESIGN: Twenty seven choroidal melanoma specimens obtained from the McGill University Ophthalmic Pathology Registry were classified as spindle cell, epithelioid cell or mixed cell type. Immunohistochemistry was performed using the standard peroxidase antiperoxidase technique with monoclonal HMB-45, polyclonal S-100, polyclonal S 100 beta and monoclonal S-100 alpha beta antibodies in formalin-fixed, paraffin embedded sections. OUTCOME MEASURE: Intensity of immunoreaction. The result was considered positive when at least five focal areas of stained cells were observed within the tumour. RESULTS: All 27 tumours were positive for HMB-45, 19 (70%) for S-100, 23 (85%) for S-100 beta, and 21 (78%) for S-100 alpha beta. No correlation was found between the intensity of the immunoreaction and cell classification. CONCLUSIONS: HMB-45 is the most reliable marker for choroidal melanomas. S-100 beta is a more sensitive marker than S-100 for choroidal melanomas regardless of cell type. Contrary to previous reports, S-100 beta should not be considered a useful immunomarker to differentiate between primary choroidal melanoma and cutaneous melanoma metastatic to the choroid. PMID- 9363342 TI - ROC analysis of Heidelberg Retina Tomograph optic disc shape measures in glaucoma. AB - OBJECTIVE: To determine the capacity of the Heidelberg Retina Tomograph (HRT) optic disc shape measures to detect glaucomatous damage. DESIGN: Prospective study. SETTING: Department of ophthalmology at a university-affiliated hospital in Vancouver. PATIENTS: Ninety-seven consecutive patients from the glaucoma centre and 129 healthy subjects selected from volunteers and employees of the department. One eye of each subject was chosen randomly. OUTCOME MEASURES: Visual fields, as assessed with the Humphrey perimeter, program 30-2, and 12 HRT shape characteristics: disc area, cup area cup/disc area ratio, rim area, cup volume, rim volume, mean cup depth, maximum cup depth, cup shape measure, height variation contour, mean retinal nerve fibre layer thickness and retinal nerve fiber layer cross-section area. ROC (receiver operating characteristic) curves were used to analyse the capacity of each HRT characteristic to detect glaucoma. RESULTS: Statistically significant difference were found between the control and glaucoma groups in age, cup area, cup/disc ratio, rim area, cup volume, rim volume, mean cup depth, cup shape measure, mean retinal nerve fibre layer thickness and retinal nerve fibre layer cross-section area (p < or = 0.003, t test). The largest (i.e., best) ROC curve area was found for cup shape measure (area = 0.812), rim area (0.809), cup/disc area ratio (0.804) and rim volume (0.768). The mean reference height was 0.31 mm (standard deviation [SD] 0.14 mm) for the control group and 0.29 mm (SD 0.12 mm) for the glaucoma group, a nonsignificant difference. CONCLUSIONS: Cup shape measure was the most predictive HRT shape characteristic. PMID- 9363344 TI - Spontaneous regression of juvenile retinoschisis. PMID- 9363343 TI - Acute angle-closure glaucoma in giant cell arteritis. PMID- 9363345 TI - Necrobiotic xanthogranuloma without dermatologic involvement. PMID- 9363346 TI - An enhancing optic nerve lesion: malignant glioma of adulthood. PMID- 9363347 TI - Economic evaluation of dorzolamide vs. pilocarpine for primary open-angle glaucoma. PMID- 9363348 TI - Oral irritant effects of nicotine: psychophysical evidence for decreased sensation following repeated application and lack of cross-desensitization to capsaicin. AB - Psychophysical methods were used to assess changes in the intensity of irritant sensations elicited by repeated application of capsaicin and nicotine delivered unilaterally to the tongue of human subjects. Whereas capsaicin (0.5 or 3 p.p.m.; repeated at 1 min intervals over 10 min) evoked progressively stronger ratings of irritation (sensitization), there was a significant decrement in irritation ratings (desensitization) to repeated application of nicotine (0.1%). A two alternative forced-choice (2-AFC) procedure was additionally used to test for self- and cross-desensitization. After the subjects had received either repeated capsaicin or nicotine, a rest period ensued followed by the 2-AFC procedure. Either capsaicin or nicotine was delivered bilaterally to the tongue and subjects were asked to choose which side yielded a stronger sensation. Following capsaicin pretreatment, subjects reported that capsaicin evoked a stronger sensation on the previously untreated side (capsaicin self-desensitization). Similar self desensitization was observed with nicotine. Furthermore, nicotine evoked a significantly weaker sensation on the side of the tongue pretreated with capsaicin (cross-desensitization). In contrast, capsaicin did not consistently evoke a weaker sensation on the nicotine-pretreated side, indicating an absence of cross-desensitization. These results are discussed in terms of physiological mechanisms that might underlie the contrasting sensory effects of nicotine versus capsaicin. PMID- 9363349 TI - Multiple olfactory activity in the human neocortex identified by magnetic source imaging. AB - To date, cortical regions activated by olfactory stimulation have not been identified precisely in humans. In this study we used magnetic source imaging to localize neuronal activity following olfactory stimulation with two odorants, hydrogen sulphide and vanillin. Peak latencies of the olfactory event-related magnetic fields corresponded to the ascending and descending slopes of the major deflections of the olfactory event-related potentials (OERP). At these latencies we obtained consistent activation of the anterior-central parts of the insula (agranular-periallocortical and dysgranular regions) the parainsular cortex and the superior temporal sulcus. No reproducible equivalent current dipoles were found in other brain areas, including the orbitofrontal cortex. For the first time, brain areas were identified that generate most components of olfactory bioresponses (OERPs) in humans. PMID- 9363350 TI - Heterogeneity of odorant-binding proteins in the antennae of Bombyx mori. AB - Different odorant-binding proteins (OBPs) were isolated from total antennal homogenates of male and female Bombyx mori. Proteins were separated according to their isoelectric point by using preparative fast-flow isoelectrofocusing. Odorant-binding proteins were identified in immunoblots by antisera raised against the pheromone-binding protein (anti-PBP) and the general odorant-binding protein (anti-GOBP2) of Antheraea polyphemus. Four proteins cross-reacting with anti-PBP were detected in males and two in females, while three proteins cross reacting with anti-GOBP2 were found in males and five in females. Both anti-PBP and anti-GOBP2 cross-reacting proteins had an apparent molecular weight of 15-16 kDa. In parallel, the same two antisera were used in immunocytochemical studies in order to determine the distribution of these proteins within the various subtypes of olfactory sensilla. The presence of multiple odorant-binding proteins within one moth species as well as their complex distribution pattern support the suggestion that soluble OBPs might have a function in odorant discrimination. PMID- 9363351 TI - Neural interaction between cortical taste neurons in rats: a cross-correlation analysis. AB - In the rat cortical taste area (CTA), we recorded 31 pairs of taste neurons and seven pairs of taste and non-taste neurons, with single or double electrodes. By using a cross-correlogram (CCG) in a stationary state, we examined the functional interaction between neurons of the pairs while activating them by taste stimulation. Though only 14.3% of the taste and non-taste neuron pairs were correlated, 54.8% of the taste neuron pairs showed correlated activities, 41.9% of them showing common inputs, including one with an additional excitatory connection. The remainder (12.9%) showed excitatory connections with a time lag of 1-3 ms. When pairs were recorded using single or double electrodes with an intertip distance of < 50 microns in a dorsoventral direction, a larger fraction had correlated activities than when the intertip distance was > 50 microns. Whereas pairs of neurons showed correlated activities in area DI whatever the vertical intertip distance was, most of the pairs having correlated activities in area GI were found within 50 microns of the vertical intertip distance. The taste profiles of common inputs to the pair were estimated on the basis of peak at time 0 in CCGs for various taste stimuli. The efficacy contribution of the source to target neurons tended to be larger when both had the same best stimulus. This tendency held true for pairs showing excitatory connections. Interlayer excitatory connections were also evident. It is concluded that a functional column with a diameter of 50 microns may present in the CTA in rats, and that information flow is larger between pairs of neurons with the same best stimulus. PMID- 9363352 TI - Detection of a target taste in a complex masker. AB - Detection thresholds for sodium chloride were compared in aqueous solution, in mixture with a sucrose masker, in mixture with a citric acid masker, and in mixture with both of these maskers together. Separately the two maskers raised the threshold of sodium chloride by three to four times, and together by over nine times, a result consistent with independence (additivity) of the two masking effects. To achieve comparable masking with either sucrose alone or with citric acid alone would require increasing their masking concentrations by about ten times. Hence multiple masking can be a far more efficient means of concealing a taste, whether an unpleasant one (e.g. the bitter taste of medicine) or a pleasant one (e.g. a salty or sweet condiment). Multiple masking has dietary and culinary significance, especially for middle aged and elderly persons concerned about salt intake, because their thresholds for NaCl, whether with or without maskers, are typically two or three times higher than those of youthful persons. PMID- 9363353 TI - Taste disks are induced in the lingual epithelium of salamanders during metamorphosis. AB - Morphological changes of oral cavity during metamorphosis with special reference to the taste organ were examined in Ezo salamanders (Hynobius retardatus) and axolotis (Ambystoma mexicanum), and compared with those in bullfrogs (Rana catesbeiana). The non-distensible tongue of salamanders changed the structure progressively during metamorphosis: a small area of the rostrum protruded and developed caudally with recession of the flat area of the tongue. The protrusion that developed on the tongue had numerous papillae, as seen in the frog tongue. The apical region of the papillae occasionally had a cell mass similar to the taste disk of frogs (termed a taste disk-like cell mass). On the flat area of the tongue, the barrel-shaped taste buds of larval salamanders were transformed into taste buds with a wider receptor area. The barrel-shaped taste buds decreased progressively during metamorphosis, while taste disk-like cell masses increased. Neuronal labeling with an antibody to neuron-specific enolase and fluorescent carbocyanine dye showed that the taste disk-like cell masses in metamorphosed salamanders were innervated by the glossopharyngeal nerve (nerve IX). Nerve IX responded to taste stimulation as well as mechanical stimulation applied to the rostral tongue. During metamorphosis the salamanders undergo transformation and rearrangement of taste organs on the tongue possibly as an adaptation to the terrestrial environment. PMID- 9363354 TI - Distribution of non-tasters for phenylthiocarbamide and high sensitivity to quinine hydrochloride of the non-tasters in Japanese. AB - The percentage of non-tasters for phenylthiocarbamide in 915 Japanese students was 9.4%. The thresholds of the edge and back of the tongue to quinine hydrochloride were significantly smaller in the non-tasters than in the tasters. The thresholds of any tongue portions to NaCl, acetic acid or sucrose did not differ between the tasters and the non-tasters. PMID- 9363355 TI - Concentration and membrane fluidity dependence of odor discrimination in the turtle olfactory system. AB - In the present study, we examined the concentration dependence of odor discrimination in turtle olfactory bulbar responses using the cross-adaptation technique. In the odorant pairs with diverse molecular structures, the degree of discrimination was unchanged or only slightly decreased with an increase in odorant concentrations, suggesting that odorants are well discriminated even at high concentrations. In the odorant pairs with closely related molecular structures, the degree of discrimination was decreased with an increase in odorant concentrations. An increase in the temperature of turtle olfactory epithelium also decreased the ability to discriminate these odorants. There was a good correlation between changes in the odor discriminating ability induced by an increase in odor concentrations and those induced by a temperature increase. The liposomes were made of lipids extracted from the turtle olfactory epithelia and changes of their membrane fluidity induced by adsorption of odorants were monitored with DPH. There was a good correlation between a decrease in odor discriminating ability and the membrane fluidity changes induced by odorants. We suggest that decreases in odor discriminating ability induced either by an increase in odor concentration or by a temperature increase are ultimately caused by changes in the membrane fluidity. PMID- 9363356 TI - Studies of human olfaction from the University of Pennsylvania Smell and Taste Center. AB - This paper, presented in part as an invited lecture on the occasion of Professor E.P. Koster's retirement from Utrecht University, summarizes a large body of human studies performed at the University of Pennsylvania Smell and Taste Center during the last 17 years. Details of the development of standardized olfactory tests are provided, including their validation and application in a wide variety of clinical and laboratory settings. Included are studies related to transduction mechanisms in olfactory coding and factors that adversely influence olfactory function (e.g. age, gender, smoking, exposure to environmental chemicals, numerous diseases). A brief discussion of the strengths and weaknesses of the olfactory vector hypothesis for neurodegenerative diseases is also presented. PMID- 9363357 TI - G-protein beta gamma subunit genes expressed in olfactory receptor neurons. AB - The expression of genes encoding G-protein beta gamma subunits was investigated in isolated olfactory receptor neurons from channel catfish. DNA sequencing of PCR products showed that the beta 1, beta 2, gamma 2 and gamma 3 genes were expressed in the neurons. Western blotting showed that at least three of these subunit proteins were expressed. This first analysis of the expression of beta gamma genes in olfactory receptor neurons suggests that these subunits may be involved in a variety of transduction events in these cells. PMID- 9363359 TI - Sympathetic burst activity: characteristics and significance. AB - 1. The activity recorded from mammalian sympathetic nerves comes in bursts, which result from large numbers of fibres firing synchronously. 2. Human sympathetic nerve activity behaves similarly to that in animals, although burst rates may be lower. 3. Vasomotor, cardiac and sudomotor nerve fibres all fire in bursts. Whether other sympathetic pathways do so is unknown. 4. Sympathetic activity is intrinsically 'bursty' but not intrinsically regular. 5. Bursting is a population phenomenon, not usually evident in the firing of individual neurons. 6. Bursts in post-ganglionic nerves are driven by synchronously firing preganglionic neurons. 7. The origin of bursts remains controversial. Preganglionic neuron properties are likely to be important in at least shaping bursts. 8. Burst amplitude, which reflects the number of fibres firing together, and burst probability are controlled independently. 9. Baroreceptors affect burst probability over a wide range, but have less effect on mean burst amplitude. How they affect burst timing within the cardiac cycle is discussed. 10. Burst probability is determined 'downstream' of the rostral ventrolateral medulla, implicating either the spinal cord or recurrent brainstem connections in burst generation. 11. Neuroeffector responses are too slow to follow individual bursts. However, bursting will promote spatial facilitation at both ganglionic and effector levels, which may increase the dynamic range of neural control. PMID- 9363358 TI - Chronobiology of nasal chemosensitivity: do odor or trigeminal pain thresholds follow a circadian rhythm? AB - Odor and trigeminal pain thresholds were studied four times each at 24:00, 04:00, 08:00, 12:00, 16:00 and 20:00 h in randomized order on different days in five healthy male volunteers. No circadian rhythm of olfactory or trigeminal thresholds were observed. However, the variability of odor, but not pain thresholds, increased from 04:00 h (thresholds between 0.4 and 1.2 p.p.m.) to 16:00 h (thresholds between 0.1 and 2 p.p.m.). It is hypothesized that environmental influences contribute to this increase in variance. PMID- 9363360 TI - Effects of locally administered argatroban on restenosis after balloon angioplasty: experimental and clinical study. AB - 1. This study was undertaken to evaluate the preventive effects of locally administered argatroban, a competitive inhibitor of thrombin-induced platelet activation, on restenosis after balloon angioplasty. 2. A hydrogel-coated balloon catheter was immersed three times in argatroban/saline solution (1 mg/mL) for 60 s, inflated to a pressure of 606 kPa and left in the rabbit common carotid artery for 1 min. The same procedure was performed, without drug, as a control. The pharmacokinetics of delivered argatroban in the arterial wall were assessed using [14C]-argatroban. Platelet deposition 2 h after balloon injury was quantified by fluorescence studies using antiplatelet antibody. Vascular smooth muscle cell (VSMC) proliferation 3 days after balloon injury was assessed by immunohistochemical staining for proliferative cell nuclear antigen (PCNA). In a clinical study, we divided 50 elective patients into two groups: argatroban and control. 3. In the experimental study, the mean quantities of argatroban at 0, 2 and 6 h after deflation were 24.63, 0.49 and 0.11 nmol/g wet weight of artery, respectively. Argatroban was undetected 24 h after deflation. Two hours after deflation, argatroban-treated arteries showed less platelet adhesion than saline treated controls. The mean number of PCNA-positive cells was 16.9 and 43.8% in the argatroban and control groups, respectively (P < 0.01). In the clinical study, the mean late gain loss was 8.2 and 27.3% in the argatroban and control groups, respectively (P < 0.05). The mean late restenosis rate was 11.1 and 41.4% in the argatroban and control groups, respectively (P < 0.05). 4. These data suggest that blood coagulation plays a significant role in VSMC proliferation after balloon injury and that locally administered argatroban using hydrogel coated balloon catheter may prevent post-percutaneous transluminal coronary angioplasty restenosis. PMID- 9363361 TI - Comparison of the effects of ouabain and brain natriuretic peptide in saline loaded sheep. AB - 1. It has been claimed that ouabain is an endogenous hormone that may be pivotal in the pathogenesis of some forms of hypertension and may exaggerate natriuresis in situations characterized by volume overload. We compared the haemodynamic, renal and endocrine effects of ouabain (at approximately 187 ng/kg per min for 2 h) with those of brain natriuretic peptide (BNP; at 5 pmol/kg per min for 2 h) in nine saline-loaded sheep in a balanced, randomized, single-blind, placebo controlled crossover study. 2. Brain natriuretic peptide infusion reduced mean arterial pressure whereas ouabain infusion caused no change. Haematocrit rose steadily during BNP infusion but fell during ouabain infusion. Neither ouabain nor BNP affected urine volume, sodium, potassium or creatinine excretion. Mean heart rate declined during the ouabain and placebo infusions, but was not altered during BNP infusion. Endogenous ouabain concentrations were not detectable at baseline or during BNP or placebo infusions, but rose to concentrations of 11 +/- 1.3 nmol/L during the ouabain infusion. 3. These results suggest that ouabain is not an endogenous hormone present at physiologically relevant concentrations. Furthermore, ouabain does not cause natriuresis during saline-loading in sheep and is therefore unlikely to be responsible for the exaggerated natriuresis seen in some forms of hypertension. PMID- 9363362 TI - Effect of dietary salt loading and high-calcium diet on vascular smooth muscle responses and endothelium function in rats. AB - 1. The present study examined the effects of concurrent manipulation of dietary calcium and salt on contractile responses of vascular smooth muscle (VSM) and endothelial function of aortic rings from Sprague-Dawley rats. 2. Salt loading enhanced the contractile response of the aortic rings to noradrenaline (NA), an effect that was blunted by a high calcium intake. 3. Removal of the endothelium and incubation of aortic rings in physiological salt solution containing methylene blue increased the sensitivity of the rings to NA. 4. The increase in the sensitivity of aortic rings induced by endothelium removal was more pronounced in aortic rings from salt-loaded rats. 5. Acetylcholine caused similar degrees of relaxation in all experimental groups, but the relaxation to histamine was smaller (P < 0.05) in salt-loaded rats than in other groups of rats; however, after removal of the endothelium, the contractile response to histamine was higher in salt-loaded rats. 6. The results indicate that the hypersensitivity of isolated aortic rings to agonists, as observed in salt-loaded rats, is due to altered responses of the VSM and not as a result of changes in the endothelium. In addition, salt loading tends to increase the synthesis of endothelium dependent relaxing factor. The ability of salt loading to enhance the contractile responses of VSM to agonists can be prevented by supplementing the diet with high calcium. PMID- 9363364 TI - Effects of AE0047 on cerebral ischaemia and oedema after middle cerebral artery occlusion in cats. AB - 1. AE0047 is a new dihydropyridine calcium antagonist with protective effects against cerebral ischaemia and the occurrence of stroke in several animal models. 2. In the present study we investigated whether AE0047 would improve the reduced cerebral blood flow (CBF) and oedema formation in cats subjected to middle cerebral artery (MCA) occlusion and compared it for efficacy with other dihydropyridine calcium antagonists with different moieties, such as nilvadipine and nicardipine. 3. Middle cerebral artery occlusion reduced local CBF (ICBF), as measured by the hydrogen clearance method, while dry weight measurement showed that water content in the cortical tissues surrounding each ICBF measurement electrode had increased after 4 h ischaemia. 4. Both AE0047 (10 micrograms/kg) and nilvadipine (30 micrograms/kg), given intravenously 20 min after MCA occlusion, produced an approximate 10% hypotensive response and significantly increased ICBF in severely and moderately ischaemic regions, grouped according to the initial reduced flow values. However, nicardipine (5 micrograms/kg bolus followed by infusion of 3 micrograms/kg per min for 60 min) failed to mitigate the reduction in ICBF despite an increase in the ICBF of the contralateral cortex. In addition, AE0047 tended to prevent an increase in cortical water content in severely ischaemic regions, whereas water content in both nilvadipine- and nicardipine-treated groups tended to increase. 5. These results suggest that dihydropyridine calcium antagonists act differently on cerebral ischaemia and oedema formation in a manner dependent on their side-chain structures and that AE0047 effectively attenuates ischaemic brain damage without aggravating oedema. PMID- 9363363 TI - Effects of intracellular Ca2+ chelating on noradrenaline release in normoxic and anoxic hearts. AB - 1. Ischaemia and anoxia induce excessive noradrenaline (NA) release in the heart by a mechanism independent of both nerve activity and extracellular Ca2+. The present study was designed to examine the potential role of intracellular Ca2+ mobilization in anoxic NA release in the heart by chelating intracellular free Ca2+. 2. In normoxic hearts, preloading with an intracellular free Ca2+ chelator (BAPTA) reduced neuronal NA release by 65%, confirming the effectiveness of the loading protocol. Release of NA independent of nerve activity occurred in hearts subjected to a 40 min period of anoxic, substrate-free and nominal Ca(2+)-free perfusion. Loading hearts with BAPTA prior to anoxia failed to reduce NA overflow (1561 +/- 147 vs 1496 +/- 206 pmol/g over 40 min). Infusion with BAPTA (20 mumol/L) during the first 25 min of the anoxic period reduced the quantity of anoxic NA release by approximately 25% from 2013 +/- 124 to 1476 +/- 207 pmol/g (P < 0.05). 3. Our results confirm that anoxic NA release is predominantly a Ca(2+)-independent process with Ca2+ mobilization from endogenous storage playing only a minor contributing role. PMID- 9363365 TI - Preventative and therapeutic effects of AE0047 on renal injury in stroke-prone spontaneously hypertensive rats. AB - 1. The present study was designed to investigate the preventative and therapeutic effects of AE0047 on renal injury compared with those of nitrendipine in stroke prone spontaneously hypertensive rats (SHRSP). 2. In the preventative study, drug administration was started before the appearance of renal injury, such as proteinuria. Treatment for 6 weeks with AE0047 (1 and 3 mg/kg, p.o.) led to a dose-related reduction in systolic blood pressure (SBP). Nitrendipine, at doses of 10 and 30 mg/kg, also lowered SBP to a similar degree to that seen with AE0047 at 1 and 3 mg/kg, respectively. 3. In the vehicle-administered SHRSP group, urinary excretion of protein (Uprotein V) increased progressively from 14 weeks of age for another 6 weeks. AE0047 at both doses maintained Uprotein V within normal levels throughout the experimental period. However, the elevation of Uprotein V was only inhibited in the 30 mg/kg nitrendipine-treated group. Urinary N-acetyl-beta-D-glucosaminide (NAG) activity in the vehicle-treated SHRSP group was elevated. Urinary NAG activity remained at a low level only in AE0047-treated groups. 4. Histopathological examination revealed severe lesions (i.e. fibrinoid necrosis, proliferative vasculitis and glomerular lesions) of the kidney in SHRSP. AE0047 treatment at each dose attenuated the development of renal lesions in SHRSP. In contrast, nitrendipine, at 10 mg/kg, was ineffective against the development of renal lesions. Although nitrendipine at 30 mg/kg suppressed the development of renal lesions, this effect was still weaker than that seen with AE0047 at 1 mg/kg. 5. In the therapeutic study, drugs were administered to 17 week-old SHRSP with moderate renal damage for 10 days. Treatment with AE0047 (1 and 3 mg/kg) produced dose-dependent decreases in Uprotein V. In the nitrendipine treated group, Uprotein V tended to decrease but the changes were not significant. 6. Histopathological studies revealed that 3 mg/kg AE0047 improved renal lesions, such as fibrinoid necrosis, proliferative vasculitis and glomerular lesions, whereas 30 mg/kg nitrendipine did not. 7. Taken together, the results indicate that AE0047 is capable of preventing proteinuria as well as renal lesions, in part via a mechanism independent of its depressor action on SBP. Furthermore, AE0047 improves proteinuria and renal lesions in proteinuria established SHRSP. Thus, AE0047 may have therapeutic potential in suppressing either the development or the progression of renal disease in hypertensive patients. PMID- 9363366 TI - Inhibition of K+ transport in human sickle cell erythrocytes by okadaic acid and sodium fluoride. AB - 1. The effect of okadaic acid and sodium fluoride on swelling- and N ethylmaleimide (NEM)-stimulated KCl cotransport was examined in blood cells from homozygote sickle cell anaemia patients. 2. Blood was drawn into heparin or EDTA by vein puncture from sickle cell patients previously diagnosed in the haematology clinics of Princess Badee'a Teaching Hospital. A standard method for measuring flux by using radioactive rubidium was used. 3. Okadaic acid strongly inhibited swelling-stimulated KCl cotransport if added before swelling. Okadaic acid and sodium fluoride added before NEM inhibited the activation of transport by NEM. Okadaic acid added after NEM did not inhibit transport. 4. The inhibition of the effects of NEM by okadaic acid and sodium fluoride indicates that activation of the flux by NEM requires the action of phosphatase. PMID- 9363367 TI - Relationship between gastric mucus synthesis, secretion and surface gel erosion measured in amphibian stomach in vitro. AB - 1. The layer of adherent mucus that protects the surface of the stomach reflects a dynamic balance between biosynthesis of glycoprotein, secretion of preformed mucus and erosion of the adherent gel layer. The present study is the first in which all these processes have been measured concomitantly and was undertaken to define interrelationships between the three parameters. 2. A chambered sac preparation of amphibian gastric mucosa is described. Biosynthesis was determined by specific incorporation of radiolabelled sugars into purified glycoprotein. Mucus secretion was determined by measuring the thickness of the adherent gel and erosion of the surface layer was assessed from the appearance of soluble mucin in the luminal solution. 3. 16,16-Dimethyl-prostaglandin (PG) E2 stimulated glucosamine incorporation by 10-fold, but did not alter the rate of incorporation of galactose. There was a rapid two-fold increase in the thickness of the adherent mucus layer but no change in the rate of erosion. Dibutyryl-cAMP also stimulated mucus release but, unlike PG, increased glycoprotein labelling by galactose. 4. Both distention or the application of a cholinergic agonist increased adherent mucus thickness. Stimulation of mucus release in response to carbachol was accompanied by a decrease in glycoprotein labelling by galactose. In contrast, the adrenergic agent noradrenaline decreased secretion but did not influence labelling. 5. These results indicate that biosynthesis and secretion of gastric mucus are subject to differential regulation. Moreover, the profile of incorporation of sugars in response to secretagogues also differs, indicating the need for caution when interpreting effects on glycoprotein biosynthesis. PMID- 9363368 TI - Adrenalectomy overcomes the blunted natriuretic response to atrial natriuretic peptide during hypocapnia in rats. AB - 1. Hypocapnia has been shown to blunt the natriuretic effect of atrial natriuretic peptide (ANP) independently of the renal nerves. In order to examine whether the adrenal glands are a limiting factor for the natriuretic effect of ANP, we evaluated the natriuretic responses of adrenalectomized rats to ANP infusion during hypocapnia. 2. Rats subjected to total adrenalectomy (ADX) or sham-operation (sham) were divided into hypocapnic and normocapnic groups depending on their arterial PCO2 levels. 3. In sham rats, ANP infusion at a rate of 12 micrograms/kg per h resulted in a smaller increase in the fractional excretion of sodium during hypocapnia (mean +/- SEM: 1.02 +/- 0.40%, n = 10) than normocapnia (3.95 +/- 0.64%, n = 9; P < 0.001). The level of fractional excretion of sodium with ANP infusion during hypocapnia was not significantly different from the level in saline-infused hypocapnic sham rats (0.93 +/- 0.62%, n = 10). In hypocapnic ADX rats (n = 11), ANP induced greater increases in the fractional excretion of sodium (5.59 +/- 1.35%) than did saline infusion (1.04 +/- 1.02%, n = 10; P < 0.002). In the absence of adrenal glands, the magnitude of natriuresis after ANP infusion during hypocapnia and normocapnia (3.32 +/- 1.07%, n = 9) were the same. 4. We conclude that the natriuretic effect of ANP is blunted during hypocapnia in the presence, but not in the absence, of adrenal glands. Our data suggest that the adrenal glands have an important role in limiting the natriuretic effect of ANP. PMID- 9363369 TI - Function in neurotoxicity: index of effect and also determinant of vulnerability. AB - 1. In neurotoxicity, functional indices may be the only available measures of effect, as many potent neurotoxic agents produce no morphological change. Examples of these are strychnine, dieldrin and pyrethroids, which produce excitation but no pathology, and barbiturates, xylene and lithium, which produce depression but no pathology. 2. In other cases where both functional and morphological effects are seen, functional measures often produce the most convenient, if not always the most specific, indices of toxicity. Appropriate functional measures can be highly sensitive, both in humans and in experimental animals, and can also give vital mechanistic information. However, it is essential that functional measures are reproducible and interpretable (some behavioural measures are not) and also provide a reasonably exacting test of function (passive observation of resting behaviour can miss many effects). 3. In addition to their use as an index of toxicity, changes in function, even within the normal range, can themselves influence susceptibility to toxins. Tissue perfusion can determine delivered dose and is influenced by function, while metabolic transformation is modified by nutritional state. Nutritional state can also influence absorption, with anaemia enhancing manganese toxicity and calcium deficiency enhancing lead toxicity. Functional activity can influence target susceptibility directly: thus, noise exposure enhances the ototoxicity of carbon monoxide, toluene or aminoglycoside antibiotics; noise, motor activity or anaesthesia all influence the central neurotoxicity of dinitrobenzene or metronidazole; motor activity enhances the peripheral nerve toxicity of lead or thallium; and nerve regeneration enhances the toxicity of hexane. These functional factors can be very important in determining individual susceptibility. PMID- 9363370 TI - A study of neurokinins and other oedema-inducing mediators and mechanisms in thermal injury. AB - 1. Mechanisms involved in the plasma extravasation observed following thermal injury of rat dorsal skin were investigated. 2. Heat applied to the dorsal skin of anaesthetized rats by a temperature-controlled skin heater (1 cm diameter) for 5 min induced temperature-dependent plasma protein extravasation at 48-48.5 degrees C, measured for up to 4 h following initiation of heat. 3. A tachykinin NK1 receptor antagonist (SR140333), a bradykinin B2 receptor antagonist (HOE 140) and a cyclo-oxygenase inhibitor (indomethacin), when given as cotreatments prior to the selected measurement period, markedly suppressed oedema formation observed over 0-1 h (P < 0.05) but not that observed over 3-4 h after injury. 4. These results indicate that although neurokinins, bradykinin and cyclo-oxygenase products may be important for the early response to thermal injury, they do not appear to play an important role in the ongoing oedema response. 5. Neutrophils accumulate at the inflammatory site by 4 h after thermal injury. Therefore, the effect of depletion of circulating neutrophils by a rat anti-neutrophil antiserum on oedema formation over the 0-4 h period was investigated. The results show that oedema formation was similar in control and anti-neutrophil-treated rats. 6. In conclusion, the data from the present study indicate that neuropeptides as well as other vasoactive mediators play a role in the acute plasma extravasation observed after thermal injury, but not in the ongoing inflammatory injury. Neutrophils, despite their presence at sites of thermal injury, do not appear to be involved in mediating the oedema formation observed up to 4 h after thermal injury. PMID- 9363371 TI - Effects of drugs on uteroplacental blood flow and the health of the foetus. AB - 1. The placental vascular bed is normally fully dilated. Therefore, changes in vascular resistance elsewhere in the body can affect uteroplacental blood flow (UBF). For example, antihypertensive drugs, such as diazoxide, hydralazine and the angiotensin-converting enzyme inhibitor captopril, cause falls in arterial pressure and, hence, in UBF. 2. Angiotensin II (AngII), prostacyclin and nitric oxide (NO) all influence uteroplacental vascular tone. Angiotensin II in a pharmacological dose (62.5 micrograms/h) had a biphasic effect on UBF in the sheep. Initially, there was a rise in UBF as pressure rose; however, by 16-24 h, UBF had fallen. The AngII-induced fall in UBF caused severe foetal hypoxia and hypercapnia. 3. Prostacyclin may protect the uteroplacental circulation from vasoconstrictors such as AngII, as the vasoconstrictor effect of AngII in the uteroplacental circulation is enhanced following indomethacin. 4. Oestrogen induced uterine artery vasodilation is nitrergic dependent. As well, nitrergic nerves alter the responsiveness of pregnant uterine arteries to noradrenaline. 5. Thus, both systemic and local factors are important in the control of UBF and in promoting foetal health and growth. PMID- 9363372 TI - Drug disposition in mother and foetus. AB - 1. In pregnancy, plasma protein binding of certain drugs is reduced due to a reduction in serum albumin concentration. Due to an increase in cardiac output in pregnancy there is a 50% increase of effective renal plasma flow, glomerular filtration rate and creatinine clearance. This results in a corresponding increase in renal drug clearance. 2. Placental transfer of small lipophilic molecules from the mother to the foetus is efficient because the placental membrane is a very thin lipophilic membrane, with a large surface area for exchange and high maternal and foetal placental blood flow rates. Nevertheless, placental transfer of relatively hydrophilic molecules is slow and this may limit foetal exposure to the drug where a single maternal dose is concerned. 3. Once a drug has crossed the placenta it passes via the umbilical vein to the foetal liver and then to the systemic circulation of the foetus, which creates a potential foetal hepatic first-pass effect. The activity of most foetal hepatic drug-metabolizing enzymes studied is much less than the adult activity and some enzymes do not appear to be expressed at all. The circulation of the foetal liver is unique because 30-70% of umbilical vein flow is shunted via the ductus venosus. There is also a difference in oxygenation and enzyme content between the left and right lobes of the foetal liver. 4. The foetal kidney is not a very effective route of elimination because renally excreted drug enters the amniotic fluid and recirculates via foetal swallowing. Moreover, foetal renal blood flow is only 3% of cardiac output, compared with 25% in the adult, and renal tubular anion secretion is absent. In conclusion, the extent of foetal exposure of maternally administered drug depends on numerous factors, in particular maternal and foetal elimination mechanisms and placental permeability. PMID- 9363373 TI - Targeted drug delivery to the skin and deeper tissues: role of physiology, solute structure and disease. AB - 1. Drug delivery through the skin has been used to target the epidermis, dermis and deeper tissues and for systemic delivery. The major barrier for the transport of drugs through the skin is the stratum corneum, with most transport occurring through the intercellular region. The polarity of the intercellular region appears to be similar to butanol, with the diffusion of solutes being hindered by saturable hydrogen bonding to the polar head groups of the ceramides, fatty acids and other intercellular lipids. Accordingly, the permeability of the more lipophilic solutes is greatest from aqueous solutions, whereas polar solute permeability is favoured by hydrocarbon-based vehicles. 2. The skin is capable of metabolizing many substances and, through its microvasculature, limits the transport of most substances into regions below the dermis. 3. Although the flux of solutes through the skin should be identical for different vehicles when the solute exists as a saturated solution, the fluxes vary in accordance with the skin penetration enhancement properties of the vehicle. It is therefore desirable that the regulatory standards required for the bioequivalence of topical products include skin studies. 4. Deep tissue penetration can be related to solute protein binding, solute molecular size and dermal blood flow. 5. Iontophoresis is a promising area of skin drug delivery, especially for ionized solutes and when a rapid effect is required. 6. In general, psoriasis and other skin diseases facilitate drug delivery through the skin. 7. It is concluded that the variability in skin permeability remains an obstacle in optimizing drug delivery by this route. PMID- 9363374 TI - Peroxynitrite: a mediator of increased microvascular permeability? AB - 1. Increased expression of inducible nitric oxide synthase (iNOS) and subsequent elevation of nitric oxide (NO) levels at inflammatory sites have led to the suggestion that peroxynitrite (the reaction product of superoxide and NO) is involved in pro-inflammatory processes. The present study has investigated the ability of peroxynitrite to induce oedema formation in the rat cutaneous microvasculature. 2. Peroxynitrite was synthesized from hydrogen peroxide and acidified nitrite. Spectrophotometry was used to measure the concentration and breakdown of peroxynitrite. It was also used to determine maximum amounts of hydrogen peroxide and sodium nitrite remaining after synthesis. 3. Oedema formation in response to intradermally (i.d.) injected peroxynitrite, hydrogen peroxide and sodium nitrite was measured by the extravascular accumulation of i.v. [125I]-albumin in the anaesthetized rat. 4. Peroxynitrite (40, 100 and 200 nmol/site) acted in a dose-dependent manner to cause a mean (+/- SEM) increase in plasma extravasation of 24 +/- 2, 55 +/- 5 and 69 +/- 6 microL, respectively (n = 4), with resulting inflammatory oedema. Peroxynitrite induced significantly larger plasma extravasation than equivalent vehicle controls at doses of 100 (P > 0.05) and 200 nmol (P > 0.001). This increased extravasation appears to be a direct microvascular response to peroxynitrite administration and not due to either a raised pH, necessary to stabilize the peroxynitrite, or contaminating concentrations of hydrogen peroxide or sodium nitrite from which peroxynitrite is formed. 5. These results suggest that peroxynitrite acts to increase microvascular permeability and oedema formation. Therefore, peroxynitrite may mediate vascular pro-inflammatory effects in addition to its direct cytotoxic activity. PMID- 9363375 TI - Sympathetic modulation of sensory nerve activity with age: human and rodent skin models. AB - 1. Sensory nerves serve an afferent role and mediate neurogenic components of inflammation and tissue repair via an axon reflex release of sensory peptides at sites of injury. Dysfunction of these nerves with age could contribute to delayed tissue healing. 2. Complementary animal and human skin models were used in the present studies to investigate changes in the modulation of sensory nerve function by sympathetic efferents during ageing. Laser Doppler flowmetry was used to monitor neurogenic skin vascular responses. 3. The animal model used skin of the hind footpad of anaesthetized rats combined with electrical stimulation of the sciatic nerve, while the human model comprised capsaicin electrophoresis to the volar surface of the forearm. Sympathetic modulation was effected by systemic phentolamine pretreatment in animals and local application in the human model. 4. The results obtained from the human model confirmed the reported decline in sensory nerve function and showed no change in sympathetic modulation with age. The results from the animal model confirm and expand results obtained from the human model. 5. The use of low (5 Hz) and high (15 Hz) frequency electrical stimulation (20 V, 2 ms for 1 min) revealed a preferential response of aged sensory nerves to low-frequency electrical stimulation parameters with differential sympathetic modulation that is dependent on the frequency of stimulation. PMID- 9363376 TI - Current issues in exercise metabolism: the crossover concept. AB - 1. Since ancient times, athletes have consumed proteins because of the belief they were the necessary substrate for optimal performance. Even though this concept was proven to be incorrect before the beginning of the 19th century, the practice continued until several decades ago. 2. By 1939, careful metabolic investigations on the changes in the respiratory exchange ratio had demonstrated that the metabolic transformations of lipids and carbohydrates were the primary sources of energy for muscular exercise. 3. Metabolic investigations on the profile of energy transformations during exercise have indicated that aspects related to exercise intensity, state of training, the availability of circulating free fatty acids, the activity of the sympathetic nervous system, resting levels of muscle and liver glycogen and muscle triglyceride concentrations have to be considered to explain a specific response. 4. In 1994, Brooks and Mercier introduced the concept of 'crossover' in their review manuscript to explain the shift in substrate utilization from lipids to carbohydrates by trained subjects when the power output was increased. In addition, the concept was advanced to reconcile divergent results by different investigators. 5. In 1995, Coggan and associates investigated the glucose kinetics of non-trained and trained subjects performing power outputs equal to 80% VO2max and concluded that the crossover concept was unable to explain their metabolic results from trained subjects. 6. Because of the importance of the topic to exercise physiologists and the uncertainties the controversy has created for teachers and researchers, the American Physiological Society Section on Environmental and Exercise Physiology scheduled a Point-Counterpoint forum at the 1997 Experimental Biology Meeting. The subsequent manuscripts of Brooks and Coggan are a result of that forum. PMID- 9363377 TI - Importance of the 'crossover' concept in exercise metabolism. AB - 1. The 'crossover' concept is a model of substrate supply during exercise which makes the following predictions. 2. Lipid is the major fuel (approximately 60%) for non-contracting skeletal muscle and the body at rest. 3. Energy flux, as determined by exercise intensity, is the major factor in determining the balance of substrate utilization during exercise. Thus, moderate and greater exercise intensities increase contraction-induced muscle glycogenolysis and glycolysis, increase recruitment of fast-twitch muscle fibres, increase sympathetic nervous system activity and down-regulate mitochondrial fatty acid uptake. 4. Glycogen and glucose utilization scales exponentially to relative exercise power output with a greater gain in glycogen than in glucose use at high power. The relationship between free fatty acid flux and power output is an inverted hyperbola. Consequently, at high power outputs, the role of lipid oxidation is diminished. 5. Factors such as endurance training, energy supply, as influenced by dietary manipulation, and prior exercise play secondary roles in determining the balance of substrate utilization during exercise. 6. Comparisons of the metabolic responses in subjects engaged in activities requiring vastly different metabolic rates or comparisons of subjects of different gender, age or training status require normalization of data to total energy flux. PMID- 9363378 TI - The glucose crossover concept is not an important new concept in exercise metabolism. AB - 1. The basic premise of the 'crossover' concept (i.e. that the balance of carbohydrate (CHO) and fat utilization during exercise depends on the interaction between exercise intensity and the individual's endurance training status) has been accepted since at least the 1930s. 2. The crossover concept differs from earlier perspectives mostly in its greater emphasis on the absolute exercise intensity as an important determinant of substrate selection during exercise. Because of this emphasis, it is argued that while trained subjects may utilize less CHO than their untrained counterparts during low- or moderate-intensity exercise, this is not true during high-intensity exercise, because during such exercise even trained persons must 'crossover' to CHO dependency. In fact, the crossover concept predicts that utilization of at least one CHO source (i.e. plasma-borne glucose) should be greater in trained subjects during intense exercise. This increase in glucose utilization is hypothesized to be supported by an enhanced rate of gluconeogenesis. 3. In direct contradiction of the crossover concept, the literature consistently shows that, compared with untrained individuals, trained subjects rely less on CHO for fuel, even during high intensity exercise. In particular, it has been shown that the rate of glucose utilization is lower in trained subjects under these conditions. Recent data from Dr Brooks' own laboratory support this conclusion and also show that this reduction in glucose use is associated with a decrease in the rate of gluconeogenesis. These recent observations confirm prior studies of moderate intensity exercise. 4. Based on the above, it is clear that the crossover concept cannot be considered an important new concept in exercise metabolism. Instead, the crossover concept actually serves to hinder understanding in this area. PMID- 9363379 TI - Effect of dietary fat reduction and increased aerobic exercise on cardiovascular risk factors. AB - 1. The combined effect of dietary fat reduction and increased aerobic exercise on coronary heart disease (CHD) risk factors was investigated in healthy, normolipidaemic, normotensive, sedentary individuals. 2. After a baseline period of 2 weeks, 21 subjects were randomly allocated to one of two intervention groups (low fat exercise (LFEX) or low fat control (LFC)) for 8 weeks. Both groups were counselled to reduce their dietary fat intake to 20-25% energy from fat. The LFEX group was also required to commence an aerobic exercise programme (4 x 45 min per week). 3. In both groups, the falls in total cholesterol seen at week 4 were not maintained at the end of the study; however, the LFEX group maintained a fall in low-density lipoprotein (LDL) of 0.21 +/- 0.11 mmol/L. At the end of the study, the LFC group experienced a fall in high-density lipoprotein (HDL)-cholesterol of 0.16 +/- 0.05 mmol/L, due to a 0.19 +/- 0.07 mmol/L fall in the HDL2 subfraction. The LFEX group experienced no change in HDL (-0.09 +/- 0.06 mmol/L) or HDL2 ( 0.09 +/- 0.05 mmol/L). 4. At the end of the study the LFEX and LFC groups experienced a 7 +/- 3 and 5 +/- 1 mmHg fall in systolic blood pressure, respectively, while the LFEX group also observed a 4 +/- 2 mmHg fall in diastolic blood pressure. 5. The benefits of a low-fat diet combined with aerobic exercise include a reduction in LDL and blood pressure, while maintaining HDL through the HDL2 subfraction. PMID- 9363380 TI - Early dynamic SPECT acquisition for the imaging of hepatic hemangiomas utilizing Tc-99m labeled red blood cells. AB - PURPOSE: To determine whether rapid, dynamic SPECT imaging with Tc-99m labeled red blood cells was technically feasible and of value in the detection of cavernous hemangiomas of the liver. MATERIALS AND METHODS: The acquisition protocol for Tc-99m labeled red blood cell imaging of hepatic hemangiomas was modified with six sequential 3-minute SPECT images replacing the planar flow phase. Delayed 20-minute SPECT of the liver was then performed 2 hours later. RESULTS: The authors present examples of pathologically proven positive and negative cases and retrospectively review their patient series. Examination of 19 patients with 41 lesions revealed no evidence of a false-positive examination results and only one false-negative result. Only one lesion seen to be positive with a 2-hour delayed study was not seen within 18 minutes. Lesions as small as 1.0 cm could be detected with a 3-minute SPECT. CONCLUSIONS: Rapid, dynamic early SPECT hemangioma imaging is feasible, provides images with relatively good quality, and can replace the planar flow phase. PMID- 9363381 TI - Effectiveness of Tc-99m sestamibi compared to Ga-67 in patients with pulmonary sarcoidosis. AB - The authors evaluated the suitability of Tc-99m MIBI to be used as an alternative to Ga-67 in pulmonary sarcoidosis imaging. Studies were performed on 21 patients. Eleven patients (group I) had been on corticosteroid treatment before the study, while 10 patients (group II) had received no treatment. Activity of sarcoidosis was assessed from clinical manifestations of the disease, pulmonary function tests, bronchoalveolar lavage, high-resolution computed tomography, and serum biochemistry. Ga-67 imaging results were abnormal in 73% of patients of group I (n = 8) and 90% of patients of group II (n = 9). Tc-99m MIBI imaging results were abnormal in 0% of patients of group I (n = 0) and 40% of patients of group II (n = 4). The lymph nodes were better demonstrated with Ga-67. Abnormal results of Ga 67 imaging were 100% sensitive to clinically active sarcoidosis, but had a relatively low specificity (33%). In contrast, abnormal MIBI imaging had very low sensitivity (11%). The authors conclude that planar Tc-99m MIBI scintigraphic images are not sensitive for the diagnosis of pulmonary sarcoidosis. PMID- 9363382 TI - Thallium-201 SPECT in differentiating bone infarction from metastatic lesions in osteosarcoma. AB - The authors present a case of bone infarction in the proximal epiphysis of the right tibia, which was caused by preoperative intraarterial chemotherapy for osteosarcoma. MR imaging revealed that suspected metastases had inhomogeneous signal intensity similar to that of the primary tumor, which made a metastatic lesion difficult to exclude. On TI-201 SPECT, no accumulation was found in the lesions, confirming that they were not osseous metastases. Consequently, this enabled limb salvage surgery to be performed with joint preservation. Intraoperative biopsy revealed no viable tumor cells in the lesion, and bone infarction was suspected. TI-201 SPECT was very useful, not only in differentiating bone infarction from tumor progression, including metastatic lesions, but also in the determination of the operative technique. PMID- 9363383 TI - False-positive uptake of TI-201 by an intracranial inflammatory pseudotumor. AB - A 28-year-old man had recurrent episodes of headache, ophthalmoplegia, and ptosis. MR imaging showed a mass within the sphenoid sinus. TI-201 imaging showed intense uptake in the region of the sphenoid sinus and right middle fossa with moderate retention of activity, suggesting the diagnosis of a viable tumor. A biopsy specimen from the sphenoid sinus revealed dense inflammatory infiltrate dominated by plasma cells, consistent with inflammatory pseudotumor. After radiation therapy, the mass showed no significant change on MR imaging, but regressed in size and uptake on the follow-up TI-201 scan. TI-201 may accumulate in nonmalignant inflammatory lesions and could mimic a viable tumor. It is, therefore, suggested that before surgery and histologic diagnosis, any abnormal intracranial accumulation of TI-201 should be interpreted with caution. PMID- 9363384 TI - Spontaneous perforation of the gallbladder during infancy diagnosed on hepatobiliary imaging. AB - Spontaneous gallbladder perforation is a very rare condition in infants. Most gallbladder perforations occur in adults, frequently due to trauma. Ultrasound, peritoneal lavage, and retrograde cholangiography may give indirect evidence of the possibility of this condition. There is no definitive diagnostic modality that can definitely determine the diagnosis in such cases. A case of gallbladder perforation with localized biliary ascites detected on radionuclide hepatobiliary imaging is presented. PMID- 9363385 TI - Hepatic uptake of Tc-99m MDP on bone scintigraphy from intravenous iron therapy (Blutal). AB - Two patients with hypochromic microcystic anemia received intravenous iron therapy (Blutal, Yuham Co., An Yang, Korea). These patients demonstrated diffuse hepatic uptake of Tc-99m MDP on bone scintigraphy, which was performed for evaluation of lower back pain in one patient and to rule out skeletal metastases from gastric cancer in the other patient. Blutal is an iron colloid chondroitin sulfate complex and is used to treat iron deficiency anemia in Korea. Phagocytized iron colloid within the hepatic reticuloendothelial system is responsible for the hepatic uptake of Tc-99m phosphate in the two presented cases. PMID- 9363387 TI - In-111 DTPA to evaluate the patency of an implanted intrathecal infusion pump. AB - In-111 DTPA cisternography confirmed placement and patency of a slow flow, implanted, programmable, intrathecal morphine infusion pump system. Other radiologic methods failed and were impractical. PMID- 9363386 TI - Scintigraphic detection of an occult bleed into a retroperitoneal mass using Tc 99m labeled red blood cells. AB - A 45-year-old man with chronic lymphocytic leukemia and a retroperitoneal mass underwent Tc-99m labeled red blood cell bleeding imaging to localize a bleeding source. The bleeding scan showed a linear accumulation of radiotracer obliquely oriented along the left upper epigastrium to the right midepigastrium. This area of uptake increased in intensity and assumed a more globular appearance throughout the study, but did not change in location. This is the pattern of a retroperitoneal bleed resulting from active hemorrhage into the retroperitoneal mass. PMID- 9363389 TI - Detection of left ventricular pseudoaneurysm during radionuclide ventriculography. PMID- 9363388 TI - Imaging of Hand-Schuller-Christian syndrome by a monoclonal antibody. AB - PURPOSE: Multifocal eosinophilic granuloma (Hand-Schuller-Christian syndrome) consists of localized lesions of histiocytosis X originating from proliferating Langerhans' cells involving male children and young adults. MATERIALS: The authors present the first case of multifocal eosinophilic granuloma that was imaged by Tc-99m monoclonal antibody BW250/183 recognizing NCA-95 antigen on granulocytes. A 30-year-old man had a diagnosis of histiocytosis X for 16 years. RESULTS: All active known lesions were visualized. The previous radiotherapy fields were also accurately demonstrated as areas with no antibody accumulation. Bone marrow biopsy taken 30 hours after injection showed no infiltrations, but mild hypoplasia suggesting chronic disease was demonstrated. Retrospectively, the authors performed digital autoradiography from tissue samples and found specific targeting with the same BW250/183 antibody. CONCLUSION: Their results indicate that antibody targeting is possible in multifocal eosinophilic granuloma, probably even allowing radioimmunotherapy. PMID- 9363390 TI - Complementary scintigraphy in tuberculous osteomyelitis. PMID- 9363391 TI - CT, MR imaging, and radionuclide imaging in a patient with hepatic involvement in primary amyloidosis. PMID- 9363392 TI - In-111 pentetreotide SPECT imaging of carcinoid tumor of the duodenum. PMID- 9363393 TI - Cerebral infarction due to traumatic internal carotid artery dissection. PMID- 9363394 TI - Adrenal mass and renal vessels mimicking intestinal bleeding on Tc-99m red blood cell scintigraphy. PMID- 9363395 TI - An unusual configuration of recanalized periumbilical veins mimicking gastrointestinal hemorrhage. PMID- 9363396 TI - Psoas muscle abscess causing fever of unknown origin: the value of Tc-99m (V) DMS imaging. PMID- 9363397 TI - Bone scintigraphy in a patient with progressive diaphyseal dysplasia. PMID- 9363398 TI - Intrauterine accumulation of F-18 FDG during menstruation. PMID- 9363399 TI - Chronic frontal sinusitis showing a ring-like accumulation demonstrated by Tc-99m HMDP bone imaging. PMID- 9363400 TI - Four and 24-hour imaging of mesoblastic nephroma with Tc-99m DMSA. PMID- 9363401 TI - Sestamibi uptake in brown tumor simulating a lung mass. PMID- 9363402 TI - Detection of pseudoaneurysm after heminephrectomy with Tc-99m labeled red blood cell bleeding study. PMID- 9363403 TI - Somatostatin receptor scintigraphy in a patient with an epigastric mass and multiple liver metastases. PMID- 9363404 TI - Detection of a cecal hemangioma with Tc-99m labeled red blood cell scintigraphy. PMID- 9363405 TI - Conduct disorder and HIV risk behaviors among runaway and homeless adolescents. AB - This study was designed to assess the prevalence of conduct disorder (CD) among runaway and homeless adolescents and to investigate associations between CD and HIV risk behaviors. The Diagnostic Interview Schedule for Children and a standardized HIV risk assessment questionnaire were administered to 219 runaway and homeless adolescents recruited from a drop-in center serving high-risk youth. One-half of the males and 60% of the females were diagnosed with CD. In multivariate analyses, CD was the strongest predictor of lifetime use of heroin and/or cocaine and exchanging sex for money, drugs, food or shelter, as well as the number of drugs used and the number of sex partners in the 3 months preceding the interview. The high rate of CD in this population, and the association between CD and both drug and sex-related HIV risk behaviors, indicate a need for interventions that consider the influence of this psychiatric diagnosis on high risk behaviors. PMID- 9363406 TI - Evaluation of the discriminative stimulus and reinforcing effects of dihydroetorphine. AB - These experiments examined whether dihydroetorphine (DHE) could serve as a reinforcer in rhesus monkeys and evoke the discriminative stimulus effects of heroin (HER) in rats, two procedures useful in predicting the overall abuse potential of compounds. Rhesus monkeys were trained to self-administer i.v. HER (10 micrograms/kg for monkeys M-BA, M-NI, and M-HO; 3 micrograms/kg for monkey M PO) during daily; 2-h experimental sessions under FR 10 Timeout 4 min schedules. VEH and doses of HER (1-30 micrograms/kg), codeine (COD; 30-1000 micrograms/kg), and DHE (1-100 ng/kg) were then substituted for the HER maintenance doses. Results indicated that DHE served as a reinforcer. The dose of DHE that maintained peak numbers of infusions was 171 and 8571 times smaller than those maintaining peak numbers of infusions of heroin and codeine, respectively. Additionally, male Sprague-Dawley rats were trained to discriminate 0.3 mg/kg HER s.c. from vehicle (VEH) in an FR 10 (fixed-ratio 10), food-reinforced, operant procedure. During tests, HER, morphine (MOR), and DHE dose-dependently evoked heroin-lever responding with ED50s of 0.055, 0.74, and 0.00033 mg/kg, respectively. These results indicate that DHE is self-administered by rhesus monkeys, and potently produces the discriminative stimulus effects of HER in rats, and suggest that DHE would have a substantial potential for abuse. PMID- 9363407 TI - Effects of information on the reinforcing, subjective, and psychomotor effects of nitrous oxide in healthy volunteers. AB - The purpose of this study was to characterize the reinforcing, subjective, and psychomotor effects of nitrous oxide (N2O) in healthy volunteers who were given different amounts of information regarding the drugs they were being administered in the experiment. A choice procedure was used in which subjects first sampled a placebo and a given concentration of N2O and then chose between the two. N2O concentration varied across the four-session experiment from 10-40%. Besides choice, subjective and psychomotor effects served as dependent measures. In the INFORMED group (n = 11), subjects were told at the beginning of each sampling trial what concentration of N2O they were inhaling or whether they were inhaling 100% oxygen (placebo). They were also informed about the prototypic effects of N2O (e.g. tingling or numbing, euphoria, dysphoria) and oxygen (e.g. no discernible effects). In the NON-INFORMED group (n = 11), subjects were only told at the beginning of each sampling trial that the drugs they would be inhaling came from one of six classes of drugs. Thirty percent N2O was chosen by a significantly higher proportion of subjects than expected by chance in the INFORMED group, but not in the NON-INFORMED group. Further, the probability of choosing 20-40% N2O was higher in the INFORMED group than in the NON-INFORMED group. Subjective effects of N2O were not affected by the information manipulation. Psychomotor performance at the highest N2O concentration tested (40%) was impaired to a greater extent in the NON-INFORMED than in the INFORMED group. We conclude that the reinforcing effects of N2O, and perhaps the impairing effects, can be modulated by telling subjects beforehand that they are inhaling N2O and what effects they might be expected to experience from the drug. PMID- 9363410 TI - The applicability of the dependence syndrome to amphetamine. AB - While current psychiatric taxonomies recognise a classification of amphetamine dependence, derived from the notion of an alcohol dependence syndrome, little research has validated that such a condition exists for this drug. Current amphetamine users (N = 331), were interviewed using the World Health Organization operationalisation of DSM-III-R substance dependence criteria, and a measure of the psychological components of dependence. Structural analyses indicated that a unidimensional dependence syndrome as assessed by DSM-III-R and DSM-IV criteria exists for amphetamine, and that physiological, psychological and behavioural indicators were all important in accounting for the variance in responses. It was demonstrated that the concept of a dependence syndrome is applicable to amphetamine, and that the inclusion of the amphetamine dependence syndrome in DSM III-R and DSM-IV is valid. PMID- 9363409 TI - Dopamine neurotoxicity in cortical neurons. AB - Dopamine (DA), at concentrations greater than 100 microM, has previously been demonstrated to be toxic to mesencephalic, striatal and dorsal root ganglion cell cultures. Pharmacological experiments suggest that DA also may play a role in the cortical neurotoxicity caused by systemic administration of N-methyl-D-aspartate receptor antagonists such as phencyclidine and MK-801. In this study, the potential toxicity of DA in primary cortical cell cultures was determined in vitro. Using calcein and ethidium homodimer fluorescence as a marker for live and dead cells, respectively, we observed that a 24 h treatment with 10-100 microM DA produced a concentration-dependent increase in the number of ethidium homodimer labelled cells. The cell death induced by 10 microM DA was dramatically reduced by co-administration of either superoxide dismutase and catalase or deferoxamine mesylate, an iron chelator. To verify this observation, the effects of 10 microM DA on the release of cytoplasmic lactate dehydrogenase (LDH) was measured. DA increased LDH release in a manner that was inhibited by both superoxide dismutase/catalase and deferoxamine. Nomifensine potentiated the effect of DA on LDH release, suggesting a protective role for DA uptake in this system. On the other hand, neither D1 nor D2 antagonists were able to prevent DA-induced LDH release. These data suggest that relatively low concentrations of DA can be injurious to cortical neurons through a mechanism that likely involves DA autooxidation and the formation of reactive oxygen species such as superoxide anion and hydroxyl radical. This mechanism may be important in the toxic effects of psychomotor stimulants such as amphetamine. However, the failure of DA receptor antagonists to affect DA-induced injury argues that the effect of DA on cortical neurons in culture does not model the toxic effect of phencyclidine and MK-801 observed in vivo. PMID- 9363408 TI - Carbohydrate deficient transferrin in detecting relapse in alcohol dependence. AB - Patients reports together with findings at clinical examination and information from an informant such as a relative were used to categorise patients as relapsed or not relapsed during a 6 month period of out-patient treatment at an alcohol problems clinic. At each fortnightly visit, blood was taken for measurement of serum gamma-glutamyl transferase and carbohydrate deficient transferrin (Pharmacia method). A total of 53 patients attended for at least one follow-up visit. Mean CDT differentiated relapsers from non-relapsers at seven of the 11 visits (P < 0.05), but at no visit did mean GGT differentiate. CDT tended to become elevated after a relapse more quickly than GGT. However, whether using upper limit of normal (ULN), or defining a 'positive test' as > last test and either > 20% above lowest previous test or > ULN, specificity (averaged over the 11 visits) was greater for GGT than CDT. Some of the false positive results for CDT were in patients who, shortly after having a positive test, relapsed, suggesting that a rising CDT can herald a relapse admitted by the patient. This could not be shown for false positive GGT results. Inspection of individual trajectories of alcohol consumption and blood test results shows that for some patients GGT is the more effective marker of relapse, whilst for others CDT operates better. PMID- 9363411 TI - Psychiatric severity and treatment response in a comprehensive methadone maintenance treatment program. AB - The purpose of this study was to investigate the influence of the severity of concomitant psychiatric symptomatology on some selected measures of methadone maintenance treatment efficacy in a comprehensive methadone maintenance treatment program (MMTP). The cohort studied included 267 patients who entered a maintenance program in the years 1991-92. Two groups of patients differing in the severity of psychiatric symptomatology were obtained on the bases of the referral to the psychiatrist and the ascertainment of a current disorder. These two groups were compared for retention in treatment, urine tests positive for morphine while in treatment and methadone dose during an observation period of 2 years. The outcome of the study suggests that on these outcome parameters, patients on MMTP who are more psychiatrically ill can perform as well as the other patients. PMID- 9363412 TI - Double-blind randomised controlled trial of lofexidine versus clonidine in the treatment of heroin withdrawal. AB - Lofexidine is an analogue of clonidine, an agonist at the alpha 2 noradrenergic receptor. Reports from preliminary open studies have suggested that it may be at least as effective as clonidine in the management of opiate withdrawal, and without the same limitation of postural hypotension. We report on a randomised double-blind comparison of lofexidine versus clonidine in the treatment of heroin withdrawal. A total of 80 hospitalized heroin addicts were randomly assigned to treatment with lofexidine or clonidine during in-patient opiate withdrawal. Maximum daily doses were 1.6 mg for lofexidine and 0.6 mg for clonidine. There was marked diurnal variation of withdrawal symptoms with severity being greatest at the daytime reading at 16.00 h and being markedly less at the night-time reading (recorded at 08.00 h). Lofexidine and clonidine were equally effective in treating the withdrawal syndrome. However, significantly more problems relating to hypotension were encountered with subjects on clonidine, with twice as many instances of withholding medication due to hypotension in the clonidine group. Better treatment retention rates were seen in the lofexidine group, although no difference was found in the proportion who had reached minimal symptom severity by the time of their discharge. We conclude that lofexidine and clonidine are equally effective, but with significantly fewer hypotensive problems with lofexidine. Further benefit from lofexidine may be possible with revised dosing regimens. Outpatient studies of lofexidine are now indicated. PMID- 9363413 TI - Polydrug dependence and psychiatric comorbidity among heroin injectors. AB - The prevalence of diagnoses of substance dependence, anxiety disorders and depressive disorders were estimated in a sample of 222 heroin injectors, using the Composite International Diagnostic Interview. Subjects had a median of three lifetime substance diagnoses and two current diagnoses. A total of 60% met the criteria for a lifetime anxiety disorder, and 51% had a current anxiety disorder. A depressive disorder was diagnosed in 41% of subjects, with 30% having a current diagnosis. There were significant positive correlations between the number of lifetime drug dependence diagnoses and the number of lifetime anxiety and affective disorders (r = 0.41), and the number of current drug dependence diagnoses and the number of current comorbid diagnoses (r = 0.32). After controlling for other variables, the only significant independent predictor of the number of lifetime and current dependence diagnoses was the number of comorbid diagnoses. PMID- 9363415 TI - Properties of human milk and their relationship with maternal nutrition. AB - The composition of human milk varies over the course of lactation and in each individual. The volume of breast milk produced is related to the weight of the infant. Human milk is markedly different from cows' milk, both in terms of macronutrients and micronutrients. This includes the types of fatty acids present and factors affecting their absorption. The types of proteins present and their relative proportions and both qualitative and quantitative differences in the non protein nitrogen fraction. There is much less lactose in cows' milk than breast milk and the oligosaccharide fraction is very different. Their are major differences in content and absorption rates of vitamins and minerals from breast milk compared to cows' milk or formula milk. Vitamin D and vitamin K status are possible problems for the breast-fed infant in certain circumstances. The nutritional status of the mother appears to influence fat concentration and thus the energy content of breast milk as well as its fatty acid composition and immunological properties. There is no coherent evidence, however, that the protein or lactose concentrations are greatly affected. There is some evidence that the concentration of vitamins in the breast milk are influenced by the mother's intake. Minerals are less variable, with the exception of selenium. The response of the infant to human and formula milk differs with respect to endocrine function, stool motility, immune function and renal function. Infant formula milks are designed to mimic human milk as much as possible, but this is unlikely to ever be completely successful. A number of important compositional differences between human milk and formula milk remain. This includes the types and proportions of fatty acids present (which may be of developmental importance), the nature of the non-protein nitrogen component (also possible developmental importance) and the presence of immunoglobulins and fibronectin (which may protect the infant against infection). PMID- 9363414 TI - Breast feeding: benefits and hazards. Methodology and summary of results. PMID- 9363416 TI - Unnatural constituents of breast milk--medication, lifestyle, pollutants, viruses. AB - It is well recognised that although nutritionally breast milk is the optimal food for babies, there are a number of caveats to this, based on the consequences of the modern lifestyle. Here we have considered ways in which the young breast fed child may be exposed to various environmental and medical contaminants which might cause adverse reactions and to which he/she may not otherwise be exposed. These substances are divided into four different areas: (i) medication taken by the mother; (ii) exposure to possibly addictive drugs taken by the mother; (iii) exposure to pollutants mainly from the maternal diet or as the result of her occupation; (iv) viruses. The infant who consumes breast milk may be exposed to a variety of chemicals which may have untoward effects on his/her immediate health and temperament and future development. Potentially hazardous substances ingested by the breast fed infant include medicaments (or their metabolites) that may have been ingested by the mother, potentially addictive common neurotoxicants such as nicotine, caffeine and alcohol, illicit drugs such as heroin and cocaine, and pollutants such as polychlorinated biphenyls and dichlorodiphenyltrichloroethane (DDT). There is a paucity of good information on which to base reliable estimates of the harm that this may cause the child. Although breast feeding is known to protect against bacterial infection, a number of viruses are excreted in the breast milk which may infect the child asymptomatically (e.g. cytomegalovirus, Epstein-Barr virus) and which are not known to be harmful, as well as human immunodeficiency virus (HIV) excretion which, in contrast, does appear to increase the risk of the child becoming infected. Balancing the risk of infection to the child born to an HIV infected mother, results in the proposition that known HIV positive women in developing countries (where the risk of gastrointestinal infection is high) should continue to breast feed but those in the developed world (where the risk of gastrointestinal infection is lower) are better advised to bottle feed. PMID- 9363417 TI - The incidence and duration of breast feeding. AB - Information obtained from a variety of sources shows different rates of initiation and duration of breast feeding and different supplementation strategies. Among populations of developing countries, in general, the mothers resident in rural-areas are more likely to breast feed than those in urban areas; in addition the better off or more highly educated are less likely to breast feed. In contrast in the developed countries, the better educated and the higher social class mothers are more likely to breast feed. There is some evidence that delay in initiation of breast feeding, lack of professional support, conflicting advice from health professionals and the presence of free samples of artificial milk (whether or not given to the mother) can result in a mother failing to establish breast feeding. Additionally, mothers who smoke cigarettes are less likely to breast feed successfully. Whilst breast feeding is almost universal in a number of developing countries, many also commonly use complementary feeds. In some countries, particularly in Asia, it is still commonplace for a child not to be given the mother's colostrum, and therefore for the first breast feed to occur well after the first 24 h. PMID- 9363418 TI - Relactation. AB - Relactation may be useful in the developing world either if the child has been ill and unable to feed for a time or the mother is ill or has died. Relactation appears to be easier with a younger infant and in women who have lactated previously. However, with appropriate care, support and motivation even some women who have never been pregnant or who have been pregnant but never lactated may be able to start lactation. PMID- 9363419 TI - Gastroenteritis, diarrhoea and breast feeding. AB - In this paper we review the literature in regard to possible relationships between breast feeding and diarrhoea or gastroenteritis. We show that in the developed as well as the developing world, there is consistent evidence of a protective effect of exclusive breast feeding in the first 4-6 months of life. The odds ratios were generally in excess of 3.0 for non-breast milk feeds. The relationship was not consistent for rotavirus infections but was consistently strong for non-viral pathogens. There are a number of indicators that suggest biological plausibility, in both the developing and developed world. The triple indicators of consistency and strength of the epidemiological associations, together with biological plausibility are major arguments for believing that there is a causal sequence involved. PMID- 9363420 TI - Does breast feeding protect against non-gastric infections? AB - There is convincing evidence that breast-feeding is protective against gastro enteritis and diarrhoea, but for other infections the situation is less clear cut. There is evidence that breast-fed infants are at increased risk of one infection (infant botulism). They are probably not significantly protected from upper respiratory tract infections (other than otitis media.), but they may be at a decreased risk of lower respiratory tract infections, particularly those associated with respiratory syncytial virus. There is strong evidence that Haemophilus influenzae B infection is more likely in the bottle-fed infant, and consistent evidence of protection of young children from chronic otitis media with prolonged breast-feeding. PMID- 9363421 TI - Eczema, asthma and allergy. AB - The literature in relation to the development of atopic and allergic disorders has been reviewed, in order to assess the claim that prolonged and exclusive breast feeding protects against the development of such disorders. The data in the literature show little consistent evidence to identify any protective association between breast feeding and either eczema, wheezing/asthma or other types of atopy or allergic response. PMID- 9363422 TI - Does breast feeding have any impact on non-infectious, non-allergic disorders? AB - Feeding of breast milk in the first weeks of life appears to have a strong protective effect against necrotising enterocolitis. Nevertheless breast milk also seems to be positively linked to the development of jaundice and to late haemorrhagic disease in infants who have not received vitamin K supplements. There is no consistent evidence that other childhood conditions such as insulin dependent diabetes or cancer are less prevalent among children who have been breast fed. Among adult conditions suggested to be less prevalent in the breast fed, only single reports of significant findings for multiple sclerosis and breast cancer exist and convincing corroboration is not available. There are a number of studies that indicate a relationship between breast feeding and later cholesterol levels--and one that has considered the mortality of ischaemic heart disease among adult males. There is some suggestion that breast feeding (during the first year of life) is the optimal protection against future raised lipid levels and mortality from coronary heart disease, but the evidence is far from conclusive. The major health advantage of breast feeding that has been clearly demonstrated remains in the protection of the infant from certain infections in early life. If there are other long-term health advantages they have yet to be fully elucidated and confirmed. PMID- 9363423 TI - Breast feeding and infant mortality. AB - The evidence linking bottle feeding to infant and early childhood mortality has been reviewed. Ecological studies of national time trends in infant mortality do not parallel breast feeding trends in those countries, and indicate that falling death rates are more likely to be related to better health care facilities and social conditions. Direct studies of deaths provide some contradictory findings; meta-analyses are not informative because of the many differences in statistical and sample methodology. The methodology exhibited in most studies is more likely to have over- rather than under-estimated a relationship between bottle feeding and infant mortality. Retrospective analyses must take account of changes in feeding pattern due to early signs of illness. Prospective population studies able to account for large numbers of potential confounders provide the best estimates, especially if proportional hazards models are used. Two such studies have been carried out--both showed protective effects of breast feeding. PMID- 9363424 TI - The growth and nutritional status of the breast-fed infant. AB - The literature on the relationship between early infant feeding and growth shows that after the first 3 or 4 months, breast-fed infants in the developed world are lighter than formula-fed infants with markedly lower adiposity. There is some evidence of a slightly lower rate of linear growth over the first year or so. These differences in weight and length do not apparently persist beyond the first few years of life. In the developing world the situation is very different. The growth curves of breast-fed infants of malnourished mothers may falter between the third and sixth month of life. However, the generally poor quality of the supplementary foods offered in the developing world and the increased risk of diarrhoeal infections mean that supplementary feeding before the age of 6 months is unlikely to lead to a growth advantage and may well lead to growth faltering. PMID- 9363425 TI - Association between breast feeding, child development and behaviour. AB - Consistent data are available to suggest that children who have been breast fed are, on average, intellectually more able than their formula-fed contemporaries. This has been shown in eight of 10 population studies and all three studies of low birthweight infants. In general, the longer the child has been breast fed the more pronounced the effect. There is evidence that breast milk that has been pasteurised before feeding does not have this effect, but that fresh breast milk is effective whether the milk is delivered by tube or by the breast. However no studies have been able to have both sufficient statistical power and the ability to allow for other confounders such as parental ability, parental IQ and other factors that might explain these findings. Additional data from studies of visual acuity show an association between breast feeding and enhanced vision which is hypothesised to be due to the unique fatty acid composition of breast milk. The differences in intellectual development might also be related to these fatty acids. Alternative explanations for the effect on intellectual development concern the possible consequences of early infections, particularly gastroenteritis, which are more common in bottle-fed babies. In contrast with the many publications on cognitive function and breast feeding, there was only one on neurological dysfunction (showing a protective effect of breast feeding) and one on childhood behaviour (using the teacher's assessment no relationship with breast feeding was found). Further research is needed in both areas. PMID- 9363426 TI - Lactation and fertility. AB - Breastfeeding suppresses ovarian activity resulting in amenorrhea and infertility. The frequency of breastfeeds and their duration appear to be important in maintaining amenorrhea--and night-time sucking appears to be particularly crucial. Supplementary feeding may affect fertility by altering suckling behaviour, but the evidence is confusing as to whether feeding supplements reduces the duration of amenorrhea and increases the risk of conception. Mothers who are better nourished tend to have a shorter period of amenorrhea than the malnourished, possibly because the infant has to suckle for a shorter period to obtain the nourishment needed. Lactation has an important effect on fertility at the population level. However, it cannot be considered a reliable contraceptive at an individual level. PMID- 9363427 TI - The effects of lactation on the mother. AB - Undernourished mothers are likely to have limited fat reserves to draw on during lactation. In order to supply nutrition to her child the mother may therefore become more malnourished and suffer from bone resorption. Repeated or overlapping pregnancies with lactation are likely to compound the issue. Little research has been carried out into the health of mothers while breast feeding, or subsequently. There are theoretical reasons to think that the malnourished mother in the developing world may be particularly vulnerable, but no studies appear to have been undertaken. Investigations in the developed world have concentrated on cancers of the reproductive organs and shown consistent evidence in large case control studies for a reduced risk of pre-menopausal breast cancer in mothers with a history of prolonged breast feeding. In contrast there have been a number of studies in the developed world concerned with emotional well-being with some indications that mothers who breast feed are more likely to be depressed and are less likely to be positive about their baby. PMID- 9363428 TI - Sialic acids--why always alpha-linked? PMID- 9363429 TI - Designing glycoconjugate biosynthesis for an insidious intent: phosphoglycan assembly in Leishmania parasites. PMID- 9363430 TI - A sequencing strategy for the localization of O-glycosylation sites of MUC1 tandem repeats by PSD-MALDI mass spectrometry. AB - It is demonstrated with glycopeptides of the polymorphic epithelial mucin (MUC1) that post-source decay matrix-assisted laser desorption ionization (PSD-MALDI) is a fast, highly sensitive, and reproducible method for the localization of O glycosylation sites by reflectron time-of-flight (TOF) mass spectrometry. We have analyzed GalNAc-carrying peptides of up to 25 amino acids, and could distinguish even neighboring glycosylation sites. This method was also able to localize and characterize disaccharides (e.g., the Thomsen-Friedenreich disaccharide) on MUC1 derived peptides. PSD-MALDI-MS fragment ion patterns were recorded in the positive ion mode from the synthetic peptide TAP25 [(T1aAPPAHGVT9S10APDT14RPAPGS20) T1bAPPA], an overlapping sequence of MUC1 tandem repeats, which was glycosylated with GaINAc in vitro. The glycosylation sites found were either Thr9 or Thr1b in the monoglycosylated, Thr9 and Thr1b in the diglycosylated, and Thr9, Thr1b, and Ser20 in the triglycosylated peptide. A single PSD-MALDI-MS spectrum of the underivatized and uncleaved di- or triglycosylated TAP25 peptide was sufficient to identify the glycosylation sites, thereby distinguishing six potential, partly adjacent, glycosylation sites. The monoglycosylated fraction was found to consist of a mixture of two glycosylated species with the same molecular weight. This was shown by the analysis of proteolytic digests. PSD-MALDI-MS of the resulting peptides right out of the digestion probe was sufficient to identify the Gal-NAc-glycosylation sites as either Thr9 or Thr1b, respectively. Beyond the methodical aspects the results revealed that in vitro glycosylation of the TAP25 peptide with a transferase system from human milk differs from that obtained with a breast cancer cell transferase system. PMID- 9363431 TI - Isolation and characterization of dolichol-linked oligosaccharides from Haloferax volcanii. AB - Biosynthesis of procaryotic glycoproteins has been studied in some detail only in the extreme halophile Halobacterium halobium. To extend these studies for a moderate halophile, dolichol phosphate-linked oligosaccharides were isolated and characterized from Haloferax volcanii. Mannosyl (beta 1-->4)galactosyl phosphodolichol could be characterized as a main component by GC/MS permethylation analysis, mass spectrometry and 1H-NMR-spectroscopy. Furthermore, two additional components, present in lower quantities, were partially characterized and identified as a tetrasaccharyl phosphodolichol containing mannose, galactose, and rhamnose in the ratio of 2:1:1 as well as another dihexosyl phosphodolichol. Both the latter compounds contain an additional charged group. All these oligosaccharides were found to be linked to a dolichol consisting of 11 or 12 isoprene units including a saturated omega-terminal isoprene residue. PMID- 9363432 TI - Characterization of serum beta-glucuronyltransferase involved in chondroitin sulfate biosynthesis. AB - We studied a glucuronyltransferase involved in chondroitin sulfate (CS) biosynthesis in a preparation obtained from fetal bovine serum by heparin Sepharose affinity chromatography. This enzyme transferred GlcA from UDP-GlcA to the nonreducing GalNAc residues of polymeric chondroitin. It required Mn2+ for maximal activity and showed a sharp pH optimum between pH 5.5 and 6.0. The apparent Km value of the glucuronyltransferase for UDP-GlcA was 51 microM. The specificity was investigated using structurally defined acceptor substrates, which consisted of chemically synthesized tri-, penta-, and heptasaccharide serines and various odd-numbered oligosaccharides with a GalNAc residue at the nonreducing terminus, prepared from chondroitin and CS by chondroitinase ABC digestion followed by mercuric acetate treatment. The enzyme utilized a heptasaccharide-serine GalNAc beta 1-4GlcA beta 1-3GalNAc beta 1-4GlcA beta 1 3Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser and a pentasaccharide-serine GalNAc beta 1-4GlcA beta 1-3Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser as acceptors. In contrast, neither a trisaccharide-serine Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser nor an alpha-GalNAc-capped pentasaccharide-serine GalNAc alpha 1-4GlcA beta 1 3Gal beta 1-3Gal beta 1-4Xyl beta 1-O-Ser that is a model compound of the reaction product formed by the action of the alpha-GalNAc transferase recently demonstrated in fetal bovine serum (Kitagawa et al., J. Biol. Chem., 270, 22190 22195, 1995) was utilized as an acceptor. Besides, all nonsulfated odd-numbered oligosaccharides except for the trisaccharide GalNAc beta 1-4GlcA beta 1-3GalNAc served as acceptors and the transfer rates roughly increased with increasing chain length. Moreover, 6-O-sulfation of nonreducing terminal GalNAc markedly enhanced GlcA transfer, whereas 4-O-sulfation had little effect on it. These results indicated that at least two glucuronyltransferases are involved in the biosynthesis of CS and that sulfation reactions may play important roles in chain elongation. PMID- 9363434 TI - Acceptor specificity of GDP-Fuc:Gal beta 1-->4GlcNAc-R alpha 3-fucosyltransferase VI (FucT VI) expressed in insect cells as soluble, secreted enzyme. AB - As an extension of previous study (de Vries et al., 1995, J. Biol. Chem., 270, 8712-8722) the acceptor specificity of recombinant FucT VI, expressed in insect cells as soluble enzyme, and purified from the growth medium by affinity chromatography, was analyzed toward a broad panel of oligosaccharide and glycoprotein substrates. It was found that FucT VI effectively utilizes any type 2-chain based structure (Gal beta 1-->4GlcNAc-R). Neutral as well as sialylated structures are fucosylated with high efficiency. To identify polar groups on acceptors that function in enzyme binding, deoxygenated substrate analogs were tested as acceptors. FucT VI had an absolute requirement for a hydroxyl at C-6 of galactose in addition to the accepting hydroxyl at C-3. Thus, FucT VI, although different from FucT III, IV, and V in acceptor properties, seems to bind the acceptor in a similar way. PMID- 9363433 TI - Complex N-glycans in Mgat1 null preimplantation embryos arise from maternal Mgat1 RNA. AB - Mice with a null mutation in the Mgat1 gene lack N-acetyl-glucosaminyltransferase I (GlcNAc-TI; EC 2.4.1.101), and die at mid-gestation. This result suggested that development of Mgat1-/- blastocysts and their implantation could occur in the absence of complex and hybrid N-glycans. However, inner cell mass of all blastocysts from several Mgat1 +/- heterozygous crosses bind the lectin E-PHA, indicating that Mgat1 null mutant blastocysts are able to synthesize complex N glycans (Campbell et al., (1995) Glycobiology, 5, 535-543). In order to directly test this hypothesis, Mgat1-/- blastocysts were positively identified by polymerase chain reaction (PCR) of genomic DNA. Reverse transcriptase PCR (RT PCR) of RNA isolated from the same blastocysts, and restriction analysis of the PCR products, revealed that Mgat1 null blastocysts contained Mgat1 RNA derived from the wild-type Mgat1 gene. Consistent with this, all 3.5 day blastocysts from five heterozygous crosses bound the lectin L-PHA, a lectin previously shown not to bind to E8.5 or E9.5 Mgat1-/- embryos that lack complex N-glycans (Ioffe and Stanley (1994) Proc. Natl. Acad. Sci., USA, 91, 728-732). Blastocysts of 4.5 days postcoitum (dpc) obtained by culturing 3.5 dpc blastocysts also bound L-PHA. However, mutant embryos that did not bind L-PHA were present among progeny from E5.5 onward. Therefore, the effects of the Mgat1 null mutation are not operative until sometime between implantation and E5.5, due to the continued presence of maternally derived Mgat1 mRNA in preimplantation embryos. PMID- 9363435 TI - Structural aspects of glucans formed in solution and on the surface of hydroxyapatite. AB - Streptococcus mutans glucosyltransferases (GtfB, -C, and -D) and their products formed from sucrose, glucans, play an essential role in the pathogenesis of dental caries. Enzymatically active Gtf is found in whole human saliva (solution), and incorporated into the salivary pellicle that is formed on teeth in vivo (surface). GtfB glucans are predominantly 1,3-linked; however, surface formed glucans from GtfB contain greater amounts of 3-linked glucose than glucans formed in solution. In contrast, the major linkage of glucans formed on the surface by GtfB in the presence of sucrose and starch hydrolysates in 4-linked glucose. GtfC-derived glucans in solution have a major linkage of 6-linked glucose, while surface-formed glucans from the same enzyme have 3-linked glucose as the major linkage. GtfD glucans formed either in solution or on the surface are predominantly 1,6-linked; however, surface-formed glucans contain more 6 linked glucose than solution-formed glucans. Digestion with the glucanohydrolases mutanase and dextranase shows differences in susceptibility among glucans formed either in solution or on the surface by each of the Gtf enzymes, and differences are also seen in the soluble end products from these digestions. Our results show that the same Gtf enzyme can form structurally distinct glucans in solution and on a surface. These observations are important in the study of naturally occurring microbial films. PMID- 9363436 TI - Digalactosyl diacylglycerols, plant glycolipids rarely found in bacteria, are major membrane components of bacteroid forms of Bradyrhizobium japonicum. AB - The membrane lipids of free living and bacteroid forms of Bradyrhizobium japonicum, obtained from nodules occupied by both typed and untyped bacteria, were isolated and characterized by a combination of NMR spectroscopy, mass spectrometry, and other chemical and physical methods. These studies indicated that both the free living and bacteroid forms of this organism contain glycolipids almost exclusively of the type found in plant cells. In the bacteroid forms, there was a dramatic shift towards the synthesis of digalactosyl diacylglycerol as the major lipid. This glycolipid has rarely been found outside of the plant kingdom and photosynthetic bacteria, and its occurrence in the bacteroid form of a plant symbiont is therefore remarkable. The presence of plant cell and organelle contaminants in the bacteroid preparations was ruled out by scanning electron microscopy, Southern blot analyses for plant DNA using specific gene probes, and chemical analyses for plant marker steroids, steroid glycosides, and cerebrosides. Digalactosyl diacylglycerol is not found in the plasma membrane of plant cells (of which the peribacteroid membrane is an extension) but is thought to be restricted to plastids. This result follows our earlier finding that the other predominant plant glycolipid, sulfoquinivosyl diacylglycerol, is a membrane component of fast growing Rhizobia and is found even when cells are cultivated in free culture where there is no question of plant contamination. The near absence of these lipids in the membranes of bacteria outside of this special group of organisms and photosynthetic bacteria suggests that the trait could have been passed on through gene transfer from plants to the bacteria at some point during the development of their symbiotic relationship. In the case of digalactosyl diacylglycerol, there is also the possibility that some common biosynthetic intermediates are used by both the plant and the bacteria. This is a striking parallel with some host-pathogen interactions. PMID- 9363437 TI - Biochemical and enzymatic characterization of blood group ABH and related histo blood group glycosphingolipids in the epithelial cells of porcine small intestine. AB - Non-acid glycosphingolipids were isolated from small intestinal epithelial cells of a single blood group A pig. One very predominant blood group compound was obtained chemically pure upon HPLC fractionation. It was characterized by mass spectrometry and 1H NMR spectroscopy to be the type 1 chain blood group A hexaglycosylceramide. Support for the presence of minute amounts of additional A glycolipids was obtained by mass spectrometry and immunostaining of TLC plates with anti-A antibodies specific for A type 2 chain, A type 3 and 4 chain, and the ALe(b) determinant. Among precursor chains, globoside (type 4) and lactotetraosylceramide (type 1) were immunologically identified, whereas no neolactotetraosylceramide (type 2) and gangliotetraosylceramide reactivities were detected. We addressed the question whether the predominant expression of type 1 chain based A glycolipids reflects a restricted glycolipid precursor chain specificity of the alpha 1-2 fucosyl- and/or the alpha 1-3 N acetylgalactosaminyltransferases, or if the biosynthesis of the precursor chains themselves is regulated. All precursor core saccharides, lacto- (type 1), neolacto-(type 2), and gangliotetraosylceramide as well as globopentaosylceramide (type 4), could serve as acceptors for fucose in vitro when a crude microsomal fraction obtained from mechanically released, porcine intestinal epithelial cells was used as an enzyme source. Under the same conditions an N-acetylgalactosamine residue could be transferred to the blood group H structures based on these core saccharide chains. Lactotriaosylceramide, but not gangliotriaosylceramide, could serve as an acceptor for UDP-galactose. When the product was digested with beta galactosidase (EC 3.2.1.23) from S.pneumoniae, under conditions where it specifically cleaves Gal beta 1-4 residues, approximately 40% of the radioactivity was cleaved off, indicating that a substantial amount of neolactotetraosylceramide was made in vitro, as opposed to the predominance of lactotetraosylceramide-based structures found in vivo. PMID- 9363438 TI - Generation of constitutive and inducible trans-sialylation dominant-negative phenotypes in Trypanosoma brucei and Trypanosoma cruzi. AB - Trans-sialylation is a unique enzymatic process that is restricted to some trypanosome species. By expressing developmentally regulated trans-sialidases, these protozoan parasites cleave sialic acids from host glycoconjugates and transfer them to acceptors on their own cell surfaces. The biological function of this process is not understood, but trans-sialylation is expected to be important in the invasion of mammalian cells by Trypanosoma cruzi and the survival of Trypanosoma brucei within its insect vector. Since a conventional gene knockout approach was precluded, we developed a dominant-negative strategy, in which fusion proteins consisting of a bacterial sialidase and trypanosome proteins were expressed in T.brucei and T.cruzi. The strong recombinant sialidase activity shifted the reaction equilibrium from sialic acid transfer to hydrolysis, in this way creating a sialic-acid-negative phenotype. Taking advantage of a recently introduced inducible expression system, we were able to control the expression of sialidase fusion proteins in T.brucei. Reversion of the sialic-acid-negative state to wild-type sialylation was accomplished by selective inhibition of the foreign sialidase, leaving the parasite trans-sialidase unaffected. Both desialylation and resialylation of trypanosomes was rapidly achieved. Our results show that neither T.brucei nor T.cruzi require sialic acids for survival in vitro, ruling out the involvement of sialylation in cell surface integrity. The versatile system introduced here will allow a detailed in vivo study of the role of trans-sialylation during the trypanosome infection cycle. Furthermore, cell surface sialic acids are implicated in a multitude of (patho-) biochemical processes in other organisms. The quantitative and qualitative manipulation of cell surface sialic acids, by expressing of counteracting enzymes, constitutes a novel approach with potentially broad applications in glycobiology. PMID- 9363439 TI - Molecular characterization of a major high molecular weight mucin from human sublingual gland. AB - Human submandibular/sublingual gland secretions contain a multimeric high molecular weight mucin (MG1) and a monomeric low molecular weight mucin (MG2). MG2 is the product of the MUC7 gene, whereas the gene for MG1 has not been identified. Previously, we isolated a clone (pSM2-1) from a human sublingual gland cDNA expression library using an antibody against deglycosylated MG1 (Troxler et al., Biochem. Biophys. Res Commun., 217, 1112-1119, 1995). In order to identify the mucin gene from which pPM2-1 was derived, Northern blots of human submandibular and sublingual gland RNA were hybridized with a series of probes for tandem repeats found in the high molecular weight secreted mucins MUC2, MUC3, MUC4, MUC5AC, MUC5B, and MUC6. The only known mucin expressed at high levels in sublingual gland was MUC5B, and no known mucin was expressed at high levels in submandibular gland. A series of overlapping clones was obtained by rescreening the sublingual gland cDNA library and by reverse transcriptase-polymerase chain reaction. The resulting clones connected pSM2-1 to a series of MUC5B tandem repeats at the 3' end of the repeat domain and provided the complete nucleotide and deduced amino sequence of the carboxyl terminal region of MG1. This region is enriched with respect to cysteine (approximately 10 mol %) and contained a D domain and a carboxyl terminal domain that could be aligned with the corresponding domains in human intestinal MUC2, human tracheobronchial MUC5AC, and human von Willebrand factor. The limited expression of known mucin genes, together with the considerable mucin synthesizing capacity of submandibular gland, suggests that a novel (previously not described) mucin gene is expressed in this gland and constitutes a portion of MG1 in salivary secretions. PMID- 9363440 TI - Cloning and characterization of a sialidase from the murine histocompatibility-2 complex: low levels of mRNA and a single amino acid mutation are responsible for reduced sialidase activity in mice carrying the Neu1a allele. AB - The Neu1 locus, in the S region of the murine histocompatibility-2 complex, regulates the sialic acid content of several liver lysosomal enzymes. Three alleles, Neu1a, Neu1b, and Neu1c, have been described on the basis of differential sialylation of the enzyme liver acid phosphatase. The Neu1a allele occurs in a small number of mouse strains, e.g., SM/J and is associated with sialidase deficiency. We recently described G9, a sialidase gene in the human major histocompatibility complex (Milner et al. (1997) J. Biol. Chem., 272, 4549 4558), and we now report the characterization of the equivalent gene in mouse. The protein product of the murine G9 gene is 409 amino acids in length and is 83% identical to its human orthologue. Expression of the murine G9 protein in insect cells has confirmed that it is a sialidase, with optimal activity at pH 5. To elucidate the basis of sialidase deficiency in mouse strains carrying the Neu1a allele, we have sequenced the G9 coding regions from mice carrying the three Neu1 alleles and hence defined the amino acid sequence characteristic of each allotype. Of particular interest is a Leu-209 to Ile mutation that is unique to the Neu1a allotype and is associated with reductions in sialidase activity of approximately 68% and approximately 88% compared to the Neu1b and Neu1c allotypes, respectively, when these three protein variants are expressed in insect cells. Additional factors, such as differential expression, may also influence the activities of the Neu1 allotypes in vivo. We have observed that the level of G9 mRNA is substantially reduced in mice carrying the Neu1a allele compared to the Neu1b (85-95% reduction) and Neu1c (approximately 70% reduction) alleles. PMID- 9363441 TI - Beta 1,4 N-acetylgalactosaminyltransferase (GM2/GD2/GA2 synthase) forms homodimers in the endoplasmic reticulum: a strategy to test for dimerization of Golgi membrane proteins. AB - Many Golgi membrane-bound glycosyltransferases exist as intermolecular disulfide bonded species, some of which have been demonstrated to be homodimers. Evidence for homodimer formation has come primarily from radiation inactivation experiments. We utilized an alternative strategy to test for homodimer formation of the cloned beta 1,4 N-acetylgalactosaminyltransferase (GalNAcT) responsible for synthesis of the glycosphingolipids GM2, GD2, and GA2. We stably transfected CHO cells with myc epitopetagged GalNAcT, which localizes primarily to the Golgi, and a hemagglutinin (HA) epitope-tagged GalNAcT fusion protein in which the cytoplasmic domain of GalNAcT was replaced by an ER retention signal. We then sought evidence for dimer formation between the two forms of GalNAcT. Immunoprecipitation with anti-myc or anti-HA co-immunoprecipitated the HA-tagged form or the myc-tagged form, respectively, providing evidence for the physical association of the two forms of GalNAcT. As a result of this association, GalNAcT/myc increased in the ER as demonstrated by Western blots and immunofluorescence. The rapid formation of dimers provided further evidence for dimer formation occurring in the ER. In summary, these results demonstrate that GalNAcT forms homodimers as a result of intermolecular disulfide bond formation in the ER. Furthermore, this ER motif strategy is potentially useful for demonstrating homodimer formation of other Golgi enzymes. PMID- 9363442 TI - The yeast CWH41 gene encodes glucosidase I. AB - N-Glycosylation in the yeast Saccharomyces cerevisiae entails the synthesis of a Glc3Man9GlcNAc2 oligosaccharide precursor which is subsequently transferred to suitable protein acceptors, a process which is conserved among all eukaryotes. Processing of the oligosaccharide occurs immediately following this transfer, the first step being the removal of the terminal alpha-1,2-linked glucose by glucosidase I in the endoplasmic reticulum. Although yeast glucosidase I has been isolated, the yeast gene encoding this enzyme has not yet been identified. In the present work, it is shown that Cwh41p, a yeast endoplasmic reticulum protein previously identified as being required for normal cell wall beta-1,6-glucan synthesis (Jiang, Sheraton, Ram, Dijkgraaf, Klis, and Bussey (1996) J. Bacteriol., 178, 1162-1171), has significant amino acid similarity to the product of the human glucosidase I cDNA. Tetrad analysis for glucosidase I activity in vitro and in vivo was done on the progeny from the spores obtained from the heterozygous diploid, cwh41 delta::HIS3. It is shown that, unlike CWH41 cells, cell extracts obtained from cwh41 delta null mutants are unable to release glucose residues from the synthetic trisaccharide substrate alpha-D-Glc 1-->2 alpha-D-Glc 1-->3 alpha-D-Glc-O(CH2)8 COOCH3 in vitro. Following 1 h labeling of cells with [3H]mannose, analysis by high pressure liquid chromatography of the labeled N-linked oligosaccharides, combined with treatment with jack bean alpha mannosidase and yeast glucosidase I, shows that the oligosaccharides isolated form a cwh41 delta null mutant are fully glucosylated, retaining the three terminal glucose residues, whereas the oligosaccharides from CWH41 cells do not have any glucose residues. These results showing a lack of glucosidase I activity in cwh41 delta null mutants both in vitro and in vivo are consistent with the structural evidence that CWH41 encodes the yeast glucosidase I. PMID- 9363443 TI - Can HPV typing predict the behaviour of cervical epithelial neoplasia? PMID- 9363444 TI - Comparison of A and B-type lamin expression in reactive lymph nodes and nodular sclerosing Hodgkin's disease. AB - AIMS: In order to clarify the differentiation and proliferation status of the Reed-Sternberg and Hodgkin cells we studied A and B-type lamin expression with specific monoclonal antibodies in nodular sclerosing Hodgkin's disease. Its normal counterpart, the reactive lymph node, was also examined for lamin subtype expression. METHODS AND RESULTS: The CD20 positive centrocytes and centroblasts of the follicle centre in the reactive lymph nodes expressed lamin B1, but were not or only very weakly positive for lamin B2 or A-type lamin antibodies. Mantle zone lymphocytes displayed lamins B1 and B2, but were negative for A-type lamins. Furthermore, CD3- and CD20-positive lymphocytes in the medulla and paracortex lacked A-type lamins, but were positive for both B-type lamins. Finally, the proliferation marker Ki67 was mainly detected in the centroblasts, but also in a fraction of the A-type lamin negative cells in the paracortex and medulla. In Hodgkin's disease, all cells expressed lamins B1 and B2, whereas A-type lamins were primarily observed in CD30-positive Reed-Sternberg and Hodgkin cells. About 20% of the Reed-Sternberg and Hodgkin cells expressed Ki67, with co-expression of lamin A in most of these cells. CONCLUSIONS: Ki67 and A-type lamin staining were in general mutually exclusive in lymph nodes, indicating that A-type lamin positive cells are not proliferative. This suggests also that the A-type lamin expression in Reed-Sternberg and Hodgkin cells is correlated with a relatively mature phenotype of these malignant cells. However, some of these differentiated malignant cells still have a capacity to proliferate as indicated by Ki67 positivity. Our observation that lamin B2 expression in the follicle centre cells of the reactive lymph node is low or absent indicates that this lamin subtype is not always expressed in nucleated cells, which is in clear contrast to the results obtained in previous studies in other diseases and in normal tissues. Absence of lamin B2 expression may be associated with the follicle centre stage of B-cells. PMID- 9363445 TI - Enteropathy-associated T-cell lymphomas have a cytotoxic T-cell phenotype. AB - AIMS: Enteropathy-associated T-cell lymphoma (EATCL) is a rare complication of coeliac disease. We investigated whether EATCLs are the neoplastic counterparts of activated cytotoxic T-cells (CTLs). METHODS AND RESULTS: Eight cases, clinically and histologically defined, were stained with monoclonal antibodies against components of the cytotoxic granules of CTLs, granzyme B and T-cell restricted intracellular antigen (TIA-1). It was found that all cases had a cytotoxic phenotype, i.e. expression of TIA-1 in most of the tumour cells, whereas granzyme B was found in six of eight cases, mostly in a smaller number of tumour cells compared to TIA-1. Since TIA-1 and granzyme B are expressed at different stages of activation of CTLs it is hypothesized that differences in expression between granzyme B and TIA-1 in EATCL represent different stages of activation in which the tumour cells are arrested. Clinically, seven of the eight patients died within 10 months after diagnosis of EATCL. CONCLUSIONS: EATCL is a clinicopathological entity with a grim prognosis and with tumour cells representing a unique neoplastic equivalent of CTLs arrested in varying stages of activation. PMID- 9363446 TI - Gastrointestinal tumour masses due to multiple myeloma: a pathological mimic of malignant lymphoma. AB - AIMS: To describe and evaluate two cases of gastrointestinal involvement by multiple myeloma. METHODS AND RESULTS: Clinical details were obtained from patients records and routine histopathological sections were correlated with haematological and immunohistochemical investigations. As shown in the accompanying illustrations, myeloma manifests as large, atypical, non-cohesive cells which may mimic high-grade lymphoma. CONCLUSIONS: Extraskeletal spread of multiple myeloma occurs more frequently than is currently recognized, but clinical involvement of gut is rarely reported. Gut involvement may occur soon after initial diagnosis of myeloma and may be of serious clinical consequence. Histologically, it may mimic high-grade lymphoma. Failure to recognize myelomatous involvement of gut may result in inappropriate surgery or oncological therapy. PMID- 9363447 TI - Hepatic stem-like cells in hepatoblastoma: expression of cytokeratin 7, albumin and oval cell associated antigens detected by OV-1 and OV-6. AB - AIMS: In a recent study we described a population of small epithelial cells (SEC) in human hepatoblastoma that exhibit ultrastructural features of the oval cell of rodents. Both SEC and oval cells are immunoreactive for cytokeratin 7, a marker of biliary differentiation, and it was postulated that SEC, like oval cells, are closely related to hepatic stem cells. This study was undertaken to investigate whether SEC also exhibit immunolabelling for albumin, a marker of hepatocytic differentiation, and to determine whether other antigens typical of oval cells are detectable in hepatoblastoma. METHODS AND RESULTS: Hepatoblastomas of various subtypes were investigated by electron microscopy, and by immunohistochemistry with the monoclonal antibodies OV-1 and OV-6, which recognize antigens associated with oval cells. Double-labelling for cytokeratin 7 and albumin was carried out by immuno-electron microscopy. OV-1 stained scattered cells in seven of 12 tumours investigated and OV-6 in nine. On immunoelectron-microscopic investigation, SEC exhibited labelling for both cytokeratin 7 and albumin. CONCLUSIONS: The results demonstrate that antigens associated with oval cells are found in certain cells in hepatoblastoma. SEC, like oval cells, co-express markers for hepatocytic and biliary differentiation. The findings further support the hypothesis that SEC are closely related to the putative bipotent hepatic stem cell, which, by definition, gives rise to both hepatocytes and biliary epithelial cells. PMID- 9363448 TI - Expression of stratified epithelial-type cytokeratins in hyalinizing trabecular adenomas supports their relationship with papillary carcinomas of the thyroid. AB - AIM: To evaluate the cytokeratin pattern of expression of hyalinizing trabecular adenomas and to verify whether or not these tumours, that share morphological features with papillary carcinomas, present the stratified epithelial-type cytokeratins commonly found in ordinary papillary carcinomas. METHODS AND RESULTS: This study consisted of the immunohistochemical detection of simple and stratified epithelial type cytokeratin filaments in a series of six hyalinizing trabecular adenomas, three papillary carcinomas with a trabecular growth pattern and two carcinomas combining hyalinizing trabecular and papillary patterns. Simple epithelial-type cytokeratins 7, 8, 18 and 19 were found in every case. Expression of the stratified epithelial-type cytokeratins 1, 5/6 and/or 13 was detected in four hyalinizing trabecular adenomas. CONCLUSION: Based on this, as well as on the cytological features and on the frequent co-occurrence of hyalinizing trabecular adenoma and papillary carcinoma, we suggest that the former lesion may be considered a peculiar encapsulated variant of papillary carcinoma. PMID- 9363449 TI - Clinicopathological and interphase cytogenetic analysis of desmoid tumours. AB - AIMS: Recurrence of desmoid tumours is difficult to predict from only histological findings. In this study, immunohistochemistry for counting stromal blood vessels and proliferative activity, DNA flow cytometry, and interphase cytogenetic analysis of chromosome 8 by fluorescence in-situ hybridization (FISH) were performed to assess the correlation between their parameters and the recurrence of desmoid tumours. METHODS AND RESULTS: The cases examined included 16 extra-abdominal desmoid and eight abdominal desmoids, comprising 14 recurrent and 10 non-recurrent cases. Eleven (69%) of the 16 extra-abdominal desmoids and three (38%) of the eight abdominal desmoids recurred. Patients with recurrent lesions (mean age, 20 years) were younger than those with non-recurrent tumours (34 years). Histologically, tumours with hypervascular areas frequently recurred after surgery in comparison with those with hypovascularity. There was no significant correlation between tumour size, the labelling index of the proliferating cell nuclear antigen (PCNA) and the recurrence. In flow cytometric analysis, all the cases examined showed a diploid pattern. The FISH study revealed that the incidence of trisomy 8 was significantly higher in the recurrent (72.7%) than in the non-recurrent cases (12.5%). CONCLUSIONS: These results suggest that a subgroup of desmoid tumours at risk of recurrence may be hypervascular lesions associated with trisomy 8. PMID- 9363450 TI - Down-regulation of CD95 (Fas/Apo-1) in the epithelia of adenovirus-infected appendices. AB - AIMS: Adenoviral inclusions are commonly seen in appendices from infants with intussusception. They are associated with focal epithelial budding and less frequently with epithelial shedding. These morphological changes could depend on the opposing effects of adenoviral gene products on CD95-mediated apoptosis. METHODS AND RESULTS: Appendices from intussusceptions with viral inclusions (n = 4) and normal appendices (n = 10) were studied by immunochemistry with anti adenovirus, anti-CD95 and anti-HLA-DR antibodies. Apoptosis was studied by the TUNEL method. The mucosa of normal appendices contained no adenoviral protein. CD95 was present in all epithelial cells except Paneth cells. HLA-DR was absent in epithelial cells and apoptosis was seen only in germinal centres and in a few surface epithelial cells. The epithelium of appendices from intussusceptions contained nuclear inclusions labelled with anti-adenovirus antibody, always found in the epithelial buds. The epithelial CD95 pattern was drastically altered in adenovirus-infected appendices. CD95 was absent from the budding foci. In these foci, HLA-DR was overexpressed. There was also increased epithelial apoptosis in areas remote from those lacking CD95 antigen. CONCLUSIONS: The appearance of epithelial budding or shedding in appendices from intussusception could be due to focal in situ differences in the expression of adenoviral genes. PMID- 9363451 TI - The extent of apoptosis is inversely associated with bcl-2 expression in premalignant and malignant breast lesions. AB - AIMS: In this study we investigated the extent of apoptosis in benign, premalignant and malignant breast lesions and its association with the immunohistochemical expression of bcl-2 oncoprotein. METHODS AND RESULTS: In order to detect apoptotic cells and bodies in tissue sections, the 3'-end DNA labelling method was used. Immunohistochemical staining was performed by using the avidin-biotin-peroxidase complex technique. A monoclonal antibody against bcl 2 oncoprotein was used and the specificity of the antibody was confirmed by immunoblot analysis. According to the results the extent of apoptosis, as determined by the apoptotic index, was lowest in benign ductal hyperplasias and sclerosing adenoses (0.15% and 0.07%, respectively). It was moderately elevated in atypical hyperplasias and in-situ carcinomas (0.20% and 0.40%, respectively) and highest in invasive carcinomas (0.76%). In ductal invasive carcinomas, grade I lesions showed a lower apoptotic index (0.52%) than grade II (0.72%) and grade III (1.17%) carcinomas. The apoptotic index was not significantly lower in lobular (0.82%) than in ductal invasive carcinomas (0.85%). bcl-2 immunohistochemistry was inversely related to the apoptotic index. In all cases studied the inverse association was very strong (P = 0.0004) but it was also present when only carcinomas were analysed (P = 0.01). In benign and atypical hyperplasias, bcl-2 positivity was observed in all cases, but such cases were less frequent in in-situ lesions and in invasive carcinomas. CONCLUSIONS: The results show that there is an inverse relationship between the extent of apoptosis and bcl-2 expression in breast lesions suggesting that its expression affects the regulation of apoptosis in them. PMID- 9363452 TI - Clinicopathological characteristics of peripheral primitive neuroectodermal tumour of skin and subcutaneous tissue. AB - AIMS: To study the clinical and pathological features of primary malignant peripheral primitive neuroectodermal tumours (PNETs) of the skin and subcutaneous tissue, to discuss the differential diagnosis, and to review the existing literature on these tumours. METHODS AND RESULTS: Eight cases of PNETs presenting in the skin and subcutaneous tissue were identified from the pathology records of the Christie Hospital, Manchester. Detailed immunohistochemical studies were performed on all cases and seven tumours were subjected to electron microscopic examination. Detailed clinical and follow-up information was obtained on seven cases. Six tumours occurred in children and adolescents and two were seen in young adults (age range, 8-36 years). No sex or site predilection was observed. Five tumours occupied the dermis and subcutis and three were entirely located in the subcutaneous tissue. Microscopically, they were composed of small round cells and seven tumours contained glycogen. Only one tumour focally exhibited Home Wright rosettes and neuropil. Two tumours contained rhabdoid or plasmacytoid cells in places and all cases showed microcystic and pseudovascular spaces. Immunostains revealed MIC2 (8/8), NSE (7/8), PGP9.5 (7/8), beta 2 microglobulin (7/8), neurofilament protein (6/8), S100 protein (3/8), synaptophysin (2/8) and Leu-7 (1/8) positivity. Anomalous cytokeratin (4/8), desmin (2/8), myoglobin (2/8), NKIC3 (4/8) and GFAP (1/8) staining was also noted. Ultrastructurally, neuroendocrine granules were detected in five cases and one case exhibited microtubules in processes. Adequate follow-up information was available in four cases. One patient died of metastatic disease. One child developed axillary lymph node metastasis but is alive with no evidence of disease 96 months after treatment. Two other patients are alive with no residual or recurrent disease 44 and 52 months after excision and radio/chemotherapy. CONCLUSION: PNETs are rare malignant small round cell tumours of the skin and subcutaneous tissue which are probably underdiagnosed. A correct diagnosis can be made on light microscopic features, demonstration of neuroendocrine granules on electron microscopy and a combination of MIC2, beta 2 microglobulin, and more than one neural marker positivity. These neoplasms should be differentiated from other cutaneous neoplasms composed of small round cells. The number of cases of cutaneous PNETs studied so far is rather small, and no firm conclusion can be drawn about their behaviour but long-term survival is possible in some cases. PMID- 9363454 TI - Adenomyoepithelioma of the skin: a case report with immunohistochemical and ultrastructural observations. AB - AIMS: The histological, immunohistochemical and electron microscopic features of a primary adenomyoepithelioma of skin, a rare sweat gland tumour, are reported. METHODS AND RESULTS: The tumour occurred on the back of a 92-year-old woman. It was composed of well-formed tubules lined by epithelial cells surrounded by clear or spindled myoepithelial cells. Immunohistochemically, the epithelial cells exhibited strong cytokeratin (CAM5.2) and weak carcinoembryonic antigen positivity. The myoepithelial cells showed diffuse positivity for smooth muscle actin and focal positivity for S100 protein. Ultrastructurally, the myoepithelial cells contained myofilaments with focal densities and hemidesmosomes. They were limited by well-formed basal lamina. The tumour was associated with a small eccrine spiradenoma. CONCLUSION: We predict that the tumour will behave in a benign fashion. There is no evidence of recurrence or metastasis 28 months later. PMID- 9363453 TI - Erythrophagocytic tumour cells in melanoma and squamous cell carcinoma of the skin. AB - AIMS: Erythrophagocytosis is a characteristic feature of tumour cells in malignant histiocytosis, some leukaemias, lymphomas, and also reactive histiocytes in the haemophagocytic syndrome associated with a variety of infections and neoplasms. It has also been found exceptionally in metastatic malignant epithelial cells in bone marrow and lymph nodes. We present two cases, a cutaneous malignant melanoma and an acantholytic squamous cell carcinoma, in which erythrophagocytosis by tumour cells was demonstrable by both light and electron microscopy. METHODS AND RESULTS: The melanocytic and squamous nature of these cells was supported by the immunohistochemical detection of HMB45, S100, and NKI-C3 in the former, and cytokeratin and EMA in the latter, and at ultrastructural level by the presence of melanosomes and tonofilaments, respectively. CONCLUSIONS: This is, to our knowledge, the first documented report of erythrophagocytic tumour cells in human melanomas and primary carcinomas. Biological considerations apart, this unusual feature can prove to be of value to avoid a misdiagnosis of a variety of haematopoietic malignancies. PMID- 9363455 TI - Pancreatic tissue in a lateral cervical cyst attached to the thyroid gland--a presumed foregut remnant. AB - AIM: To report the previously undescribed occurrence of a lateral neck cyst, attached to the thyroid gland, containing pancreatic tissue. METHODS AND RESULTS: A 41-year-old man presented with a recurrent cystic lesion of the thyroid. At thyroidectomy cystic masses containing mucinous material were present in the neck, and there was a nodular lesion attached to the lower pole of the thyroid. Histological examination of the latter lesion revealed an epithelial lined cyst, with pancreatic tissue (exocrine and endocrine) in addition to fat, fibrous tissue, muscle and cartilage in the wall. CONCLUSIONS: The possible origin of this structure is discussed, with the conclusion being that it most likely represents a foregut remnant. PMID- 9363456 TI - Multinucleated stromal giant cells of testis. AB - AIMS: This study documents the frequency of multinucleated stromal giant cells within the interstitium of the testis and looks for possible aetiological reasons for this occurrence. MATERIALS AND METHODS: We examined sections of testes from 150 unselected autopsy cases finding stromal giant cells in 43%. An aetiological association between the occurrence of multinucleated stromal giant cells in this site and hormonal or other pathogenetic influences could not be established. CONCLUSIONS: In many instances, this occurrence appears to be an age related phenomenon. PMID- 9363457 TI - Perianal Paget's disease associated with anal canal adenocarcinoma and rectal villous adenoma. PMID- 9363458 TI - Eosinophilic angiocentric fibrosis of the upper respiratory tract: a postscript. PMID- 9363459 TI - Choroid plexus papilloma with chondroid metaplasia. PMID- 9363460 TI - Pseudosarcomatous myofibroblastic proliferation of the spermatic cord (proliferative funiculitis) PMID- 9363461 TI - Tumour angiogenesis and prognosis. PMID- 9363462 TI - Langerhans cell histiocytosis and metastatic lymphoepithelioma-like carcinoma of the parotid. PMID- 9363463 TI - Heterotopic bone (osteohamartoma) in the lung. PMID- 9363464 TI - [Recent progress in surgical management for urogenital cancers--improvement of patients' QOL following surgery]. AB - We report our experience of urinary reconstruction with ileal neobladder, and nerves-paring radical cystoprostatectomy or radical prostatectomy in an attempt to improve quality of life (QOL) in patients following surgery. While the ileal neobladder is not always indicated for patients who require cystectomy for invasive bladder carcinoma, voiding through the urethra in this urinary reconstruction contributes to improvement of post-cystectomy QOL. Daytime continence is achieved in 90% of patients. However, nighttime incontinence was found in 30%, which indicates a need for further refinement of the operative procedures or more investigations into the mechanism of continence in this condition. Recovery of erectile function following nerve-sparing radical cystoprostatectomy or prostatectomy was found in 50% of the patients who received this procedure. Subjective and objective erectile capacity before operation partly determine post-operative erectile function. Several patients whose post operative erectile function was recovered had not had sexual intercourse after surgery. Anxiety about the disease, still inadequate penile rigidity and a non cooperative attitude of the sexual partner were involved in the results, suggesting that more careful care and counseling before and after operation are required. PMID- 9363465 TI - [Autoantibodies and thrombosis]. AB - During late seventies it became apparent that the appearance of antiphospholipid antibodies is associated with thromboembolic manifestations, such as cerebral or myocardial infarction, pulmonary thromboembolism, deep vein thrombosis, intrauterine fetal losses and thrombocytopenia. The term antiphospholipid syndrome has been used to define this set of pathologic features. Recognition of this syndrome has spread worldwide as its clinical implications have become appreciated. Recent studies showed that cofactor, beta 2-glycoprotein I (beta 2 GPI) is required for binding of anticardiolipin antibodies (aCL) raised in the patients with SLE and related other autoimmune disorders. However, this finding has generated considerable controversy. Four different hypotheses have been proposed to explain the specificity of aCL: (1) CL is directly recognized by aCL; (2) the beta 2-GPI-CL complex is the structure recognized by aCL; (3) the beta 2 GPI is the actual target antigen for aCL but is cryptic in the absence of CL; and (4) the actual epitope for aCL appears on the native structure of beta 2-GPI. We showed that aCL bound to beta 2-GPI interacting with poly-oxygenated plates and in the absence of CL, an interaction which depends on introduction of oxygen atoms on the polystyrene surface. We also showed that the beta 2-GPI bound to CL via a particular region on the fifth domain, namely C281KNKEKKC288, and the tertiary structure of the region is involved in binding to phospholipid. Several mechanisms to explain the vascular injury and thrombosis associated with aCL have been proposed, primarily based on their phospholipid reactivity to activated platelets. Whether aCL-through binding to complex of beta 2-GPI and negatively charged phospholipid in the phospholipid-dependent coagulation reactions of hemostasis contribute to the increased risk of thrombosis in patients with aCL is an important question in need of an answer. We have demonstrated the possibility that not only activated platelets but also oxidized lipoproteins, e.g., low density lipoprotein (LDL), may be thrombogenic targets of aCL which recognize the altered beta 2-GPI structure. PMID- 9363466 TI - [Experimental studies concerning about the effects of the portal arterialization 4 weeks after ligation of hepatic artery under the optimal arterio-portal shunt blood flow]. AB - The changes of hepatic hemodynamics and hepatic oxygen metabolism after portal arterialization (APS) were studied. Beagle dogs were used for the experiments. Dogs were grouped as follows: group I (n = 6) had 2 days of APS, group II (n = 6) had 1 week of APS, group III (n = 6) had 4 weeks of APS. Portal arterialization performed by the anastomosis between the end of the hepatic artery and the hepatic portion of the side of the portal vein following ligation of the hepatic artery, the gastro-duodenal artery and the right gastric artery. It has been confirmed that arterio-portal shunt flow of this experimental model is the optimal arterio-portal shunt flow by the basic study. In all groups, total hepatic blood flow increased more than about 120% of its initial value, and was controlled after 2 days, 1, or 4 weeks, there were no significant variation with the first postoperative determination. Portal vein pressure, portal vein resistance did not present significant changes compared with the preoperative determination. Hepatic oxygen delivery, hepatic oxygen consumption and hepatic oxygen extraction ratio presented no significant changes compared with the preoperative determination in all groups. Concentration levels of serum GOT, GPT, total bile acid elevated significantly in group I, but in group II and III, there was no significant difference compared with the preoperative level. AKBR and mGOT were not significantly different compared with the preoperative level in all groups. Histologically, the liver structure, common bile duct and portal vein showed no ischemic change compared with the control biopsy in all groups. In conclusion, this study showed portal arterialization under the optimal arterio portal shunt flow has beneficial effects on liver under hepatic arterial obstruction for 4 weeks. PMID- 9363467 TI - [Contribution of L-arginine-derived nitric oxide to the structural integrity of coronary artery and cardiac interstitium, and to the regulation of sympathetic nerve activity: assessment using a rat model produced by chronic nitric oxide inhibition]. AB - A chronic model of hypertension, induced by continuous inhibition of nitric oxide synthase (NOS), was used to examine whether chronic NOS inhibition is associated with the heightened sympathetic activity and how nitric oxide (NO) produced by NOS contributes to maintain structural integrity of coronary artery and myocardial interstitium. Osmotic pumps were implanted intraperitoneally for 4 or 8 weeks to male Wistar rats. Solution in the osmotic pumps contained 0.2 M L-NG nitroarginine methylester (LNAME) [low dose (LD)] or 1 M LNAME [high dose (HD)], or saline (SA). Sproke-prone spontaneous hypertensive rats (SHRSP) served as hypertensive controls. After 4 weeks the pumps in some rats were exchanged to the ones containing same solution (SA-SA, LD-LD, and HD-HD), or LNAME was discontinued and replaced by SA (LD-SA, and HD-SA). After 4 weeks, blood pressure (BP) of the LNAME-treated rats gradually rose from 112 to 142 (LD) and 180 (HD) mmHg. When the LNAME treatment was continued for the next 4 weeks, BP remained high (140 mmHg) in LD-LD. When LNAME was discontinued, BP returned to control levels (LD-SA: 110 mmHg; HD-SA: 122 mmHg). Heart rate (HR) decreased soon after initiation of the LNAME treatment, and remained lower in LD and LD-LD for 8 weeks, while it was gradually elevated and reached to the control level in HD. Discontinuation of the LNAME treatment normalized HR (LD-SA and HD-SA). Plasma dopamine levels were lower in the LNAME-treated rats and the withdrawal of LNAME normalized them. Plasma norepinephrine levels were significantly higher in HD than SA and LD, and it returned to control level in 8 weeks. Plasma renin concentrations were unchanged throughout the study. Microscopic examination (ME) revealed more severe thickening of coronary arterioles and fibrosis of myocardial interstitium in HD than in SHRSP. ME also revealed severe histiocyte infiltration in HD rats, while no kidney damages. These results suggest that, in the chronic model of hypertension induced by sustained LNAME administration, not only NO derived from endothelial NOS (NOS-3), but also the heightened sympathetic drive caused by central NOS (NOS-1) inhibition modifies progression of the disease. Furthermore, NOS-2 induced by histiocyte infiltration and its inhibition by LNAME may have resulted in the severe structural changes in the lesions. Thus, various NOSs may take part in maintaining cardiovascular integrity. PMID- 9363468 TI - [A study on mechanisms of thymic selection by intrathymic administration of antigenic peptides]. AB - In the process of T cell differentiation thymocytes undergo positive and negative selections. The positive and negative selections result from interactions between the T cell antigen receptor (TCR) and self peptides presented by the major histocompatibility complex (MHC) molecules. Positive selection generates functional T cells restricted to the self-MHC. Negative selection eliminates or anergies T cells bearing self reactive TCR with high affinity to self peptides plus MHC. In this study, differentiation and selection of thymocytes were analyzed using bone marrow chimeras. It was demonstrated that differentiation of CD4+CD8+ thymocytes to CD4+ or CD8+ mature thymocytes occurred between 12 and 16 days post bone marrow transplantation. When pigeon cytochrome c 43-58 related peptide antigens were injected intrathymically 13 days after bone marrow transplantation, various changes were observed in resultant T cell repertoire. Intrathymic injection of peptides with high affinity to the MHC class II resulted in specific inhibition of T cell responses to the peptides, whereas injection of peptides with low affinity to the MHC induced no alteration. Furthermore, no modification of T cell responses was observed, when these peptides were administered after 14 days post BMT. The present findings demonstrate that when peptides with high affinity to the MHC class II molecules are administered intrathymically at a critical stage of thymocyte differentiation, negative selection is induced in a manner of one peptide vs one T cell clone. PMID- 9363469 TI - [Immunological analysis of HTLV-I env-pX transgenic rat with various collagen vascular diseases]. AB - Human T lymphocyte virus type-I (HTLV-I) is an etiologic agent of not only adult T cell leukemia but also HTLV-I associated myelopathy/tropical spastic paraparesis, HTLV-I associated arthropathy and other immunological disorders, such as Sjogren syndrome, dermatitis, polymyositis, and uveitis. We recently reported that a wide spectrum of collagen vascular diseases, including inflammatory arthropathy resembling rheumatoid arthritis, myocarditis, dermatitis, necrotizing arteritis, myositis and sialoadenitis similar to Sjogren's syndrome, developed in the transgenic rat carrying HTLV-I env-pX region under the control of its own long terminal repeat (env-pX rat). To investigate the pathogenetic role of these diseases, cell surface molecules and functions of lymphocytes from env-pX rats were examined in this study. In env-pX rats with diseases, not only infiltrating lymphocytes in the inflammatory sites but also peripheral lymphocytes expressed a large number of co-stimulating molecules such as CD80/86 and ICAM-1, compared with those of normal rats or rats with adjuvant induced arthritis or myosin-induced myocarditis. Moreover, the expression of CD80/86 and ICAM-1 was already up-regulated on the surface of peripheral lymphocytes in env-pX rat before developing any diseases. Lymphocytes, taken from env-pX rats immunized with myosin in vivo, showed significantly higher cellular response against myosin in vitro than those of normal rats. Lymphocytes from env pX rats also showed the hyper-reactivity to the stimulation by super-antigens, but no significant difference of the usage of T cell receptor V beta was found compared with those of normal rats. These results suggest that the env-pX transgene may induce the high expression of CD80/86 and ICAM-1 on the lymphocytes and the resulting hyper-immune responsiveness in env-pX rats. PMID- 9363470 TI - [Development of thymic tumor in HTLV-I transgenic rats under control of a lymphoid tissue specific promoter]. AB - The p40tax protein of Human T lymphocyte virus type I (HTLV-I) is known to be a transactivator not only for the own viral gene but also for the various cellular genes (host genes), including a number of cytokine genes and genes for cell proliferation. Its tumorigenicity was also reported in vivo, such as developments of mesenchymal tumor, neurofibroma, mammary carcinoma and large granular lymphocytic leukemia, using the transgenic technique. To investigate the tumorigenicity in lymphoid tissues, a series of HTLV-I pX transgenic rats (lck-pX rats) which expressed the pX gene under control of lymphocyte specific protein tyrosine kinase (p56 lck) gene type 1 promoter was produced. In some lines of lck pX rats, pX mRNA was expressed selectively in the thymus, lymph nodes and spleen as expected. However, pX mRNA expression was also detected in other tissues from other lines of lck-pX rats. Thymic tumor with epithelial markers developed in lck pX rats as early as 8 weeks of age and high expression of pX mRNA was detected in the tumor tissue. This is the demonstration that HTLV-I pX gene causes thymic tumor in the transgenic rat and an lck-pX rat may be a suitable animal model for elucidating pathogenetic role of HTLV-I pX gene in lymphoid tissue neoplasia. PMID- 9363471 TI - Transgenerational effect of a single neonatal benzpyrene treatment (imprinting) on the sexual behavior of adult female rats. AB - Male and female rats were neonatally treated with a single dose of benzpyrene. The adult animals were mated inter se, forming control-control, benzpyrene (female)-control, benzpyrene (male)-control, and benzpyrene-benzpyrene treated couples. In the F1 and F2 generations (without any further treatment) the females's sexual behavior was tested to Meyerson index and lordosis quotient after ovariectomy and hormone treatment, using experienced males. In the F1 generation both indices were significantly reduced in the maternally treated, paternally untreated groups, however this reduction was not present in the group where the treatment was maternal and paternal alike. In the F2 generation, beside the more expressed reduction in the grandmaternally treated group, a moderate reduction in the sexual activity of progenies having treated grandfather or two treated grandparents were observed. The experiment call attention to the transgenerational sexual behavioral effect of a dangerous environment pollutant, benzpyrene. PMID- 9363472 TI - Chelation in metal intoxication LI: efficacy of amphipathic dithiocarbamates in mobilization of lead in the rat. AB - N-benzyl-D-glucamine dithiocarbamate (BG.DTC) and its analog, N-(4-methoxybenzyl) D-glucamine dithiocarbamate (MeO-BG.DTC) which are effective chelators of cadmium were investigated for their efficacy to induce excretion of lead, to reduce tissue burden of lead and to reverse certain lead sensitive biochemical alterations in lead pre-exposed rats. These were quite effective in reducing hepatic and renal but not brain lead levels as reflected by the enhanced urinary and fecal excretion of lead and in partially restoring lead inhibited blood delta aminolevulinic acid dehydratase activity. The introduction of a methoxy group at para-position of benzyl ring, unlike in case of cadmium, did not improve the lead chelating ability of the compound. The treatment with BG.DTC and MeO-BG.DTC caused depletion of endogenous essential elements such as zinc, copper and calcium as evidenced by their enhanced excretion and decreased tissue contents which were more marked in animals treated with the latter. PMID- 9363473 TI - Effect of Panpal pretreatment and antidotal treatment (HI-6 plus benactyzine) on respiratory and circulatory function in soman-poisoned rats. AB - 1 The effect of pharmacological pretreatment (pyridostigmine, benactyzine and trihexyphenidyle), designated Panpal, and antidotal treatment (the oxime HI-6 plus benactyzine) in soman poisoning was investigated in a rat model with on-line monitoring of respiratory and circulatory parameters. 2 Soman poisoning caused a high decrease in respiratory rate as well as minute respiratory volume and an increase in mean arterial pressure from 30-120 min following soman challenge. Soman at sublethal dose also significantly inhibited acetylcholinesterase activity in diaphragm and various brain parts. 3 Panpal pretreatment as well as antidotal treatment were effective in improving the respiratory and circulatory function disturbed by soman without the ability to increase significantly soman inhibited acetylcholinesterase activity in all brain parts studied. 4 The efficacy of combined Panpal pretreatment and antidotal treatment against sublethal soman poisoning was not different from the efficacy of Panpal pretreatment or antidotal treatment alone. 5 The results of this investigation suggest that Panpal pretreatment as well as antidotal treatment are able to restore respiratory and circulatory function in soman-poisoned rats without significant reactivation of brain acetylcholinesterase. PMID- 9363474 TI - The myelotoxicity of chloramphenicol: in vitro and in vivo studies: I. In vitro effects on cells in culture. AB - 1 Chloramphenicol is used extensively in non-industrialized countries for the treatment of life-threatening infections because it is cheap and effective, despite its known hemotoxicity and linkage to fatal aplastic anaemia. It is important to define the mechanism of toxicity so that means can be devised to ameliorate the toxic effects in order to produce safer usage. 2 Chloramphenicol, at concentrations from 5 mM to 2 mM initiated apoptosis in dividing cells from a monkey kidney-derived cell line and in haematopoietic progenitor cells from human neonatal cord blood. 3 Growth of progenitor cells was suppressed at concentrations of chloramphenicol which would be considered less than therapeutic during patient treatment. 4 These effects could be ameliorated in progenitor cells by co-culture with the antioxidant mercaptoethylamine and in monkey kidney cells by co-culture with vitamin C. 5 This is the first report of apoptosis in chloramphenicol toxicity and suggests a possible link between a metabolic event i.e. the production of free radicals; a morphological effect, apoptosis; and a clinical effect, bone marrow suppression and aplastic anaemia. PMID- 9363475 TI - Differential inhibition of inflammatory cytokine release from cultured alveolar macrophages from smokers and non-smokers by NO2. AB - Human alveolar macrophages (AMs) obtained from smokers and non-smokers by bronchoalveolar lavage (BAL) were subjected to various concentrations of NO2 in an inverted monolayer exposure model. Culture supernatants were collected 4 h after the exposure and assayed for secreted TNF-alpha, IL-1 beta, IL-8 and MIP-1 alpha. The steady state levels of the mRNAs for these cytokines were also analysed in the cells. The adherence of BAL cells to plastic prior to exposure to the gas elevated the steady state mRNA levels of all four cytokines tested in smoker's cells and that of TNF-alpha and IL-1 beta, but not IL-8 (MIP-1 alpha not tested), in non-smoker's cells. Interestingly, adherent cells from non-smokers released circa 15-, 3-, 1.5- and 3-fold the amounts of IL-1 beta, IL-8, TNF-alpha and MIP-1 alpha, respectively, than smoker's cells during control incubation or exposure to air. A 20 min exposure to NO2 (5 or 20 p.p.m.) did not increase the secretion of any of the cytokines from either cell type. In contrast, NO2 caused a concentration-dependent inhibition of the secretion of all cytokines except IL 1 beta from smoker's cells. Additionally, NO2 greatly diminished the release of all cytokines in response to further treatment with lipopolysaccharide (LPS). In contrast, only the secretion of TNF-alpha from non-smoker's cells was inhibited by the gas in a concentration-dependent manner, whilst LPS-induced secretion of the cytokines was not affected by the gas. The steady state levels of the respective mRNAs for each of the cytokines were not significantly affected in smoker's cells by exposure to NO2, except for a negative, dose-dependent trend in the case of TNF-alpha. Nitrogen dioxide also failed to elevate the levels of the mRNAs in non-smoker's cells but, again, tended to diminish the levels, particularly of IL-1 beta mRNA. However, exposure to the gas inhibited LPS induced accumulation of cytokine mRNAs in smoker's cells only. The data suggest that macrophage-derived cytokine mediators of the sepsis response may not play a role in the generation of NO2-induced inflammation in the human lung. Conversely, the gas seems to non-specifically inhibit the release and/or production of cytokines, particularly from smoker's cells, at the post-transcriptional level, and impairs the ability of the cells to increase the transcription and release of the cytokines in response to bacterial LPS. The fact that NO2 seriously impaired the already diminished capacity of smoker's cells to release several important pro-inflammatory cytokines, both under control conditions and in response to LPS, strongly suggest that the inhalation of NO2 in cigarette smoke may contribute to impairing host defence against infection in the lung. PMID- 9363476 TI - Environmental exposure to polycyclic aromatic hydrocarbons in Czech Republic. AB - 1 Objectives of this study were (1) to compare concentrations of individual polycyclic aromatic hydrocarbons (PAH) in air of polluted and nonpolluted area of Czech Republic during winter and summer periods and (2) to verify if urinary 1 hydroxypyrene (1-OHP), as supposed practical biological marker, permits the assessment of spacial and temporal variations in environmental PAH exposure. 2 The study population consisted of three groups: (1) a group of 22 physical exercise students who regularly train outside, from the university situated in a polluted town, spending 14 days in winter and 14 days in summer in 'non-polluted' mountains; (2) a control group of 22 residents from the town and (3) a control group of 18 residents from the mountains. 3 The total PAH concentrations (sum of 13 individual PAH) were 19.3 and 104.6 ng/m3 in town and in mountains, respectively, during summer and 86.6 and 261 ng/m3 during winter. 4 Median 1-OHP levels ranged between 0.03 and 0.13 mumol/mol creatinine for controls and between 0.04 and 0.12 mumol/mol creatinine for students. No relationship was found between pyrene levels in air and group means of urinary 1-OHP. Our results show that other factors (probably PAH in food) contribute in masking air pollution influence on urinary 1-OHP levels in subjects non-occupationally exposed to PAH. PMID- 9363477 TI - Laryngeal survey in glyphosate intoxication: a pathophysiological investigation. AB - Respiratory aspiration is a serious potential complication of glyphosate surfactant herbicide intoxication. From October 1, 1992 to June 30, 1996, we performed laryngeal evaluations in 53 cases to investigate the possible pathophysiological mechanism of glyphosate intoxication. There were 36 cases with significant laryngeal injury. The blood WBC count were significantly higher and the hospital stays were significantly longer in patients with laryngeal injury, when compared with patients with no laryngeal injury (Student t-test, P < 0.005). Laryngeal injury was strongly correlated with aspiration pneumonitis (mean 2 = 4.449, P < 0.05). We concluded that laryngeal injury may be the major cause of aspiration that leads to some degree of morbidity and mortality, following concentrated glyphosate-surfactant herbicide intoxication. Laryngeal survey may be indicated in cases of glyphosate-surfactant intoxication, to evaluate the severity of mucosal injury, and to apply adequate supportive management as early as possible to prevent from aspiration complications and even mortality. PMID- 9363478 TI - An unusual poisoning with the unusual pesticide amitraz. AB - Amitraz, 1,5 di-(2,4-dimethylphenyl)-3-methyl-1,3,5-triaza-penta-1,4-diene, a formamidine pesticide, is used worldwide. It causes side-effects in animals that resemble those caused by pure alpha 2-adrenergic agonist drugs such as clonidine. Data on poisonings in humans are scanty. We report on a case of human poisoning with amitraz with typical signs of alpha 2-adrenoreceptor stimulation. PMID- 9363479 TI - Immunotoxicotherapy: successes, disappointments and hopes. PMID- 9363480 TI - Antimalarial drugs and the mosquito transmission of Plasmodium. AB - It is well-known that whenever possible, the treatment of patients with malaria should include measures to prevent them transmitting the infection to others. This is particularly important for P. falciparum, where the gametocytes can survive for a much longer period than the asexual stages. Not all antimalarials are gametocytocidal or sporontocidal and those that are may have particular disadvantages or lose their effectiveness because of resistance. Even drugs that have no obvious gametocytocidal or sporontocidal activity may have other effects. These include the possibility of increasing transmission, either by affecting the parasite within an individual host or by selection for parasite strains with increased potential for infecting the mosquito vector. This review summarises the available information on the properties of antimalarials in relation to mosquito transmission and highlights the need for more attention to be paid to this aspect of drug action. PMID- 9363481 TI - Continuous culture of Plasmodium falciparum: its impact on malaria research. AB - The methods developed by us in 1976 for the continuous culture of the erythrocytic stages of Plasmodium falciparum make this organism available to a large variety of scientists. As a result, much has been learned about P. falciparum during the past 20 years. Here we attempt to emphasize recent developments in the diverse aspects for which the culture method has been particularly useful: chemotherapy; drug resistance; vaccine development; pathogenesis; export of proteins into the host cell; cell biology, the mitochondrion and the plastid; innate resistance involving mutant human erythrocytes; gametocytogenesis; genetics, transfection; molecular biology; biochemistry; extracellular cultivation. PMID- 9363482 TI - Plasmodium falciparum: an electronmicroscopy study of caveolae and trafficking between the parasite and the extracellular medium. AB - Caveolae containing grape-like tubulovesicular structures were observed in the cytoplasm and in the parasitophorous vacuole of ring- and trophozoite-stage Plasmodium falciparum parasites. In applique-forms intact caveolae and free vesicles were also seen to bud off the surface of infected erythrocytes directly from the parasitophorous vacuole where the parasite was in close vicinity to the host cell membrane. The mean vesicle diameter was 0.08-0.1 micron. No such structure was observed in schizonts, segmenters or in the cytoplasm of infected or uninfected erythrocytes. These structures may represent morphological evidence in P. falciparum of a "window" through which the parasite would have direct access to the extracellular milieu. They may constitute carrier vesicles containing parasite membrane transport molecules possibly involved in malaria pathogenesis and/or immunity. PMID- 9363483 TI - Remarks on the phylogeny and structure of fatty acid binding proteins from parasitic platyhelminths. AB - Four fatty acid binding proteins (FABPs) have been described in 4 parasitic platyhelminths: Schistosoma mansoni, Schistosoma japonicum, Fasciola hepatica and Echinococcus granulosus. FABPs form a multigenic family of cytosolic proteins widely distributed in metazoan tissues, the function of which is still poorly understood. These helminth proteins have recently received attention, since there are reports to indicate that S. mansoni and F. hepatica FABPs may be protective antigens. In addition, these proteins could play a major role in the parasites' life-cycles because platyhelminths are unable to synthesize de novo most of their lipids. We have undertaken phylogenetic and structural analyses of platyhelminth FABPs in an attempt to characterize features of biological relevance. Phylogenetically, these FABPs appear to be more closely related to those of vertebrate heart, mammary gland, muscle, retina, skin, brain and myelin, although no clear functional relationships were established between them. We describe several conserved motifs characteristic of specific groups of FABPs. Hydrophilicity, flexibility and accessibility analyses revealed several major putative epitopes for the E. granulosus FABP, EgDf1, that appear to be centred in loops of the EgDf1 3-dimensional structure modelled by molecular replacement. PMID- 9363484 TI - Effect of Fasciola hepatica excretory-secretory products on the metabolic burst of sheep and human neutrophils. AB - F. hepatica excretory-secretory (ES) products were found to inhibit superoxide output in phorbol myristate acetate (PMA)-stimulated sheep and human neutrophils as measured by spectrophotometry. Luminol-enhanced chemiluminescence by PMA stimulated neutrophils from both species was again inhibited. However, nitric oxide output by PMA-stimulated human neutrophils was significantly increased in the presence of ES products, whilst in sheep it was inhibited. No major effects were noted using resting neutrophils. The results are discussed in relation to the evolution of parasite defence mechanisms. PMID- 9363485 TI - Stage-specific serine and metallo-proteinase release by adult and larval Trichostrongylus vitrinus. AB - Proteinases were released in a stage-specific manner during in vitro culture by 4th larval stage and adult Trichostrongylus vitrinus. Substrate gel analyses and inhibitor studies revealed the presence of serine and metallo-proteinases, active over a broad pH range, which degraded proteins such as fibrinogen, plasminogen and fibronectin but not immunoglobulin. The adult proteinases were partially inhibited (43%) by immunoglobulin from immune lamb lymph compared to controls, indicating their relevance to parasite immunobiology in vivo. PMID- 9363486 TI - Characterization of haemolytic activity from adult Haemonchus contortus. AB - Adult Haemonchus contortus contain a detergent-soluble factor that haemolyses sheep red blood cells in a time- and concentration-dependent manner. This factor had comparable haemolytic activity at pH 5.0 and 8.0; activity was lower at pH 6.0 and 7.0. The activity was heat-stable, unaffected by proteolytic inhibitors, and inhibited by 20 mM polyethyleneglycol. Haemolytic activity was associated with the particulate fraction of the isolated intestine, suggesting an essential role for this activity in the acquisition of nutrients by disrupting host red blood cells. The data are consistent with the hypothesis that the mechanism of action of the haemolytic factor is as a pore-forming agent. PMID- 9363487 TI - A revision of Neoheterocotyle (Monogenea:Monocotylidae) with descriptions of the larvae of N. rhinobatis and N. rhynchobatis from Heron Island, Great Barrier Reef, Australia. AB - Rhinobatos typus and Rhynchobatus djiddensis were collected from Heron Island, Australia and examined for monocotylid parasites. Specimens of Neoheterocotyle rhinobatidis (Young, 1967) Chisholm, 1994 and N. rhynchobatis (Tripathi, 1959) Chisholm, 1994 were collected from the gills of Rhinobatos typus. This represents both a new host and new locality record for N. rhynchobatis. Neoheterocotyle bychowskyi (Timofeeva, 1981) Chisholm, 1994, N. nagibinae (Timofeeva, 1981) Chisholm, 1994 and N. rhinobatis (Pillai & Pillai, 1976) n. comb. were identified from the gills of Rhynchobatus djiddensis from Australia and are all new locality records. We consider N. djiddensis (Pillai & Pillai, 1976) n. comb. a species inquirenda and synonymise N. trilobata Timofeeva, 1981 with N. rhinobatis. Therefore, there are 7 valid species in the genus, including N. bychowskyi, N. forficata, N. inpristi, N. nagibinae, N. rhinobatidis, N. rhinobatis and N. rhynchobatis. The larvae of N. rhinobatis and N. rhynchobatis are described and the anterior glands of the larvae are related to those of the adults. The development of the male copulatory organ of N. rhinobatidis is described. Host specificity and geographic range of the genus are also discussed and a key to species is provided. PMID- 9363488 TI - Mosquitoes as vectors of Setaria labiatopapillosa. AB - An infected bovine-baited trap was utilised in summer 1994 to catch possible intermediate hosts of S. labiatopapillosa in northeastern Italy. Collections were made for 21 nights from 8.00 p.m. to 6.00 a.m. every 2 h and, after 12 September, every 30 min. Among the 16,159 mosquitoes sampled, 11,052 were freshly blood-fed. Most of the unfed females and a representative sample of those which had fed were identified as follows: Culex pipiens, Aedes caspius, A. vexans, Culiseta annulata, Anopheles maculipennis s.l., A. claviger and Coquillettidia richiardii. In spite of having the highest relative density, C. pipiens is the species which fed the least frequently and showed lower susceptibility and efficiency. The 2 Aedes species appear to act as vectors, particularly A. caspius, which proved to be the most efficient vector (K.I. = 0.8). A. claviger and A. maculipennis contribute to S. labiatopapillosa transmission, but their scarce presence reduces their epidemiological relevance. The other species identified showed a complete refractoriness to the infection. The risks for veterinary and medical health are discussed. PMID- 9363489 TI - Differentiation and ultrastructure of oncospheral and uterine envelopes in the nematotaeniid cestode, Nematotaenia dispar (Goeze, 1782). AB - The oncospheral envelopes of infective eggs in Nematotaenia dispar include the outer envelope with 2 sublayers, the inner envelope with a fibrillar embryophore and 2 cytoplasmic sublayers, and the oncospheral membrane. They differentiate from 3 primary embryonic envelopes, capsule, outer and inner envelope. The uterine envelopes are formed around the early embryos by processes of uterine epithelial cells, which surround the capsules. They degenerate rapidly in later stages; however, some structural components of the uterine envelopes were still visible in gravid proglottids as flattened perikarya with pyknotic, lobate nuclei, residual membranous structures and cellular debris situated usually between eggs. The following ultrastructural features of oncospheral envelopes differentiation appear to be characteristic for N. dispar: (1) lack of the outer capsule or shell in the fully mature eggs; (2) bi-layered structure of the outer envelope and tri-layered structure of the inner envelope; (3) absence of hook region membrane resulting probably from its early disintegration; (4) presence of small vesicles or "pits" incorporated into the inner envelope plasma membrane; (5) presence of densely packed microtubules in the external layer of the inner envelope; (6) changes in number of mitochondria and free ribosomes in the external and internal layers of inner envelope during egg maturation; and (7) probable "passage" of mitochondria and free ribosomes through the embryophoral pores in the developing eggs. PMID- 9363490 TI - Histological analysis of the egg capsule of the ovoviviparous polystomatid monogenean, Pseudodiplorchis americanus. AB - Transmission of Pseudodiplorchis americanus is restricted to the brief period when its host, a desert toad, enters water to spawn. The parasite accumulates its entire annual reproductive output within an elongated uterus during the 10-11 month period of host hibernation. Embryos of P. americanus, at all stages of development, are retained within the uterus which eventually becomes packed with around 150 encapsulated infective larvae. Recently formed eggs, which comprise a fertilized ovum and 2-3 vitelline cells, are closely surrounded by a primary eggshell which stains positively for acidic proteins and keratin. Initially, during passage along the proximal uterus, the egg capsule is only 60 microns in diameter, but as it passes to the distal uterus it expands to 800 microns in diameter to accommodate the growing larva. Due to chemical alterations or complete replacement of the shell, the final (secondary) egg capsule is a large sac-like structure composed of elastin. The flexible nature of this shell maximizes the numbers of infective larvae which can be stored in utero. TEM studies have revealed this capsule to be composed of multi-laminate membranes with a specialized cytoplasmic lining involved in a unique mechanism for embryo nutrition. This is the first report of an elastin-type eggshell within the Monogenea. PMID- 9363491 TI - The effect of feed intake level on the pharmacokinetic disposition of closantel in sheep. AB - Closantel (CLS), containing a trace of [14C]CLS, was administered intraruminally to sheep whose feed intake was maintained at either 800 or 400 g day-1. The kinetic disposition of [14C]metabolites was determined in rumen and abomasal fluid and particulate digesta and of CLS per se in plasma. The slower digesta flow rate in the sheep on low, compared with high, feed intake resulted in the proportion of the dose passing through the abomasum being reduced from 60 to 45%. Increased absorption of CLS from the rumen of sheep on low feed intake resulted in both higher maximum CLS concentration and greater area under CLS plasma concentration versus time curve, although the elimination half-life was independent of feed intake. Not only are the higher plasma CLS concentrations likely to increase efficacy against Haemonchus contortus, the threshold concentrations that are considered to inhibit the establishment of ingested H. contortus larvae were extended by 10-14 days. The extended CLS presence after reduced feeding, when integrated with parasite treatment programmes, provides an opportunity to reduce the impact of H. contortus infection. PMID- 9363492 TI - Preliminary characterisation of an Onchocerca volvulus aspartic protease. AB - PCR using 1 primer specific for aspartic proteases and 1 primer annealing to the vector allowed amplification of a 377 bp fragment encoding part of an aspartic protease from an Onchocerca volvulus cDNA library. Use of this fragment as a probe allowed the isolation of a larger cDNA clone. In common with 2 other nematode aspartic proteases, the O. volvulus predicted protein has several of the general characteristics of this class of proteins, but lacks specific determinants of lysosomal localisation. PMID- 9363493 TI - Parasite faunas of freshwater fish: the relationship between richness and the specificity of parasites. AB - The relationship between the host specificity of parasites and the richness of the assemblages in which they occur was examined among the parasite faunas of Canadian freshwater fishes. The prediction tested was that rich faunas would consist of both generalist and specialist parasites, whereas poor faunas would include only generalists, a pattern known as nestedness. An index of nestedness was computed for parasite faunas of fish species in 5 large families (Salmonidae, Cyprinidae, Catostomidae, Centrarchidae and Percidae) and compared with the value expected if parasite faunas are random assemblages of parasites. There was no evidence of nested patterns among any of the 5 families of fish hosts. However, since both measures of host range of parasites (i.e. number of known host species) and richness of parasite faunas are affected by how intensely the different parasites and hosts have been studied, tests of nestedness may be flawed. After correcting both variables for study effort, negative correlations were found between the mean host range of parasites and the richness of the faunas to which they belong. In other words, parasites in rich faunas occurred on average in fewer host species, because of the many specialists, than parasites in poor faunas, which are mainly generalists. This relationship was apparent in all fish but the Salmonidae; fish species in this family have been introduced to new areas much more frequently than other fish, and their parasite faunas have thus had a distinct recent history. The general trend observed in non-salmonid fish suggests that parasite colonization and speciation may have been facilitated in some fish species, but not in others. PMID- 9363494 TI - Eosinophilia in nude rats and nude mice after infection with Fasciola hepatica or injection with its E/S antigens. AB - Peripheral blood and bone marrow eosinophilia occurred in nude rats and nude mice following F. hepatica infection, with the magnitude of the response in nude rats greater than that in nude mice. Injection of E/S antigens induced eosinophilia in nude rats and a limited eosinophilia in nude mice. Bone marrow eosinophilia was greatly enhanced in Fasciola-infected nude rats, particularly 14 days after infection and later. In nude mice, bone marrow eosinophilia developed soon after infection and persisted for the duration of the experiment, but was not as marked as in nude rats. Bone marrow eosinophils in antigen-injected animals were also elevated, and again this was more marked in nude rats. The number of colonies formed in agar culture from bone marrow cells of both nude rats and nude mice also increased following infection and remained significantly elevated throughout the experiment. Bone marrow colonies in antigen-injected nude rats increased on day 8, while in injected nude mice, the number of colonies rose rapidly following injection with antigens. Thus, nude rats and nude mice develop T-cell-independent eosinophilia, which appears to originate in the bone marrow. The magnitude of eosinophilia is greater in nude rats and it has yet to be determined whether these effects have any relevance to the ability of rats, but not mice, to develop resistance to reinfection with F. hepatica. PMID- 9363495 TI - Expression of acquired immunity to Heligmosomoides polygyrus in mice concurrently infected with Trypanosoma congolense. AB - The effects of concurrent Heligmosomoides polygyrus and Trypanosoma congolense infection on the expression of acquired resistance to homologous nematode challenge were studied in female outbred TO mice. Mice were infected with 500 infective larvae (L3) of H. polygyrus and the infection was terminated by anthelminthic treatment on Day 12, when the worms were adults. Eight days later sub-groups of these pre-exposed mice, and of similar mice which had not experienced the previous infection with H. polygyrus, were either simultaneously infected with 500 L3 of H. polygyrus and 10(4) bloodstream forms of T. congolense, or with only one of these parasites, or were not infected. The experiment was monitored by routine parasitological and immunological techniques, including quantitative assessment of worm burden, trypanosome parasitaemia, growth of nematodes and measurement of the parameters reflecting pathological and antibody responses for 30 days after immunization. Concurrent H. polygyrus and T. congolense infection resulted in abrogation of the partial immunity against challenge infection with H. polygyrus in the pre-exposed mice, and in depressed humoral antibody responses following infection. Mortality was greatly reduced in pre-exposed mice infected with T. congolense alone compared to naive mice. The growth of male H. polygyrus worms was not affected by either the immune or infection status of their host. Although the increased size of the female worms from pre-exposed and then concurrently infected mice compared to similar mice infected only with H. polygyrus was significant, the egg production per worm was not affected. PMID- 9363496 TI - Cardiac potassium currents and channels. Part II: Implications for clinical practice and therapy. PMID- 9363497 TI - Coronary stenting of unprotected left main stem stenoses in elderly patients unsuitable for coronary surgery. AB - We describe five patients with severe unstable angina refractory to medical management in whom coronary angiography demonstrated a severe stenosis of the left main stem. Due to severe co-existing illnesses bypass surgery was deemed inappropriate. Angioplasty to the left main stem stenosis followed by stent deployment was performed. All five patients were successfully discharged from hospital. PMID- 9363498 TI - Percutaneous transvenous mitral commissurotomy using an Inoue balloon in children with rheumatic mitral stenosis. AB - Percutaneous transvenous mitral commissurotomy (PTMC) using the Inoue technique was performed in 557 patients with rheumatic mitral stenosis. Of these, 107 were children aged 10-18 years (mean +/- SD 14.5 +/- 2.3). All patients were symptomatic New York Heart Association (NYHA) Class II (n = 78) and Class III (n = 29). All were in sinus rhythm. Following PTMC, the mitral valve area (MVA) increased from 0.73 +/- 0.18 to 1.7 +/- 0.53 cm2 (P < 0.001). There was a significant fall in mean transmitral gradient from 15.6 +/- 5.2 to 5.1 +/- 2.3 mmHg, and in mean pulmonary artery pressure from 41 +/- 15 to 28.4 +/- 10 (P < 0.001). Cardiac tamponade developed in one patient. One patient developed severe mitral regurgitation requiring emergency mitral valve replacement. Five patients (4.7%) developed moderate mitral regurgitation. There was no mortality or cerebral embolism in any of the children. Four patients (3.7%) had oximetry evidence of atrial septal defect. Mean mitral valve area and transmitral gradient at 14 months mean follow up was 1.68 +/- 0.4 cm2 and 6 +/- 3.5 mmHg, respectively, and were comparable to the immediate post-PTMC results. Two patients (1.8%) developed restenosis. The immediate haemodynamic results in children were compared to 450 adult patients who underwent PTMC in the same period. The outcome was similar in both groups. Children were found to have significantly higher pulmonary artery pressure compared to adults. We found that PTMC using an Inoue balloon is very effective and safe in children, and consider that it should be the procedure of choice for young patients with symptomatic rheumatic mitral stenosis. PMID- 9363499 TI - Myocardial ventricular mass related to coronary artery distribution in human hearts. AB - This prospective study of 120 autopsy collected human hearts correlates the "Right Ventricle/Left Ventricle" free walls mass ratio and the ventricular mass fraction supplied by the right coronary ("Right Coronary/Ventricular Weight"). Different coloured gel injected through both coronary artery's capillary beds allowed ventricular myocardium separation to obtain the weights. In hearts without hypertrophy, mean +/- standard deviation of the "Right Ventricle/Left Ventricle" mass ratio was 0.54 +/- 0.09 for males and 0.62 +/- 0.23 for females; "Right Coronary/Ventricular Weight" mass ratios were 0.39 +/- 0.08 and 0.39 +/- 0.04, respectively. Mean +/- standard deviation of the "Right Ventricle/Left Ventricle" and "Right Coronary/Ventricular Weight" ratios were 0.37 +/- 0.05 and 0.36 +/- 0.10, respectively in hearts with "Left Ventricle Hypertrophy"; 0.56 +/- 0.07 and 0.38 +/- 0.11 in hearts "Without Hypertrophy"; 0.54 +/- 0.08 and 0.39 +/ 0.08 in hearts with "Biventricular Hypertrophy"; 0.89 +/- 0.16 and 0.49 +/- 0.06 in hearts with "Right Ventricle Hypertrophy". Means and variances are narrower for the "Right Coronary/Ventricular Weight" than that observed for the "Right Ventricle/Left Ventricle" mass ratio. It is due to the special double coronary arrangement in which every artery irrigates both ventricles. These results suggest that the usual pattern of the human coronary arteries' anatomy acts as a buffer for the ventricular mass distribution to be irrigated by both arteries in hypertrophy. PMID- 9363500 TI - Should general practitioners use the electrocardiogram to select patients with suspected heart failure for echocardiography? AB - Patient referrals from general practice for suspected heart failure are increasing the demand for echocardiograms, many of which are normal. We investigated whether general practitioners could be more selective by referring only patients with abnormal electrocardiograms for echocardiography. The electrocardiograms of 200 patients attending a heart failure clinic were analysed by a consultant cardiologist and two general practitioners. All three assessors examined the electrocardiograms independently and unaware of the echocardiography results. The correlation between abnormal electrocardiograms and left ventricular systolic dysfunction on echocardiography was assessed, together with the concordance between the assessors in their electrocardiogram interpretations. One hundred and sixty-five patients had echocardiographic evidence of left ventricular systolic dysfunction. When interpreted by a cardiologist, the electrocardiogram had a sensitivity of 89.1% and a specificity of 45.7% in predicting left ventricular systolic dysfunction. The general practitioners' results were comparable to the cardiologist's. We estimate that using the electrocardiogram to select patients could reduce the number of open access echocardiograms performed for suspected heart failure by up to 43% but would miss 10% of those with significant left ventricular systolic dysfunction. We therefore do not recommend selecting patients for open access echocardiography on the basis of electrocardiographic abnormalities. PMID- 9363501 TI - Overdrive atrial stimulation during transesophageal electrophysiological study: usefulness of post-pacing VA interval analysis in differentiating supraventricular tachycardias with 1:1 atrio-ventricular relationship. AB - We evaluated the feasibility and usefulness of overdrive atrial pacing to identify the relationship between atrial and ventricular activation in supraventricular tachycardias with a stable 1:1 atrio-ventricular (AV) conduction ratio during a transesophageal electrophysiological investigation. Overdrive atrial stimulation was performed in 42 consecutive patients (11 males and 31 females; mean age 49 +/- 17 years) during AV junctional reentrant tachycardia, orthodromic AV reentrant tachycardia and ectopic atrial tachycardia (22, 13 and seven subjects, respectively). Trains of 12 stimuli at a constant rate were introduced starting at a cycle length 10 ms shorter than the tachycardia cycle length; stimulation was repeated with a 10-ms decrement in pacing cycle length at each step until tachycardia terminated and/or second-degree AV block occurred. The difference between the VA interval duration at baseline and in the first post pacing tachycardia beat was measured at each step and provided identification of the AV relationship. At least one post-pacing VA interval was evaluable in 90% of the cases and measured 2 +/- 4 and 1 +/- 3 ms in AV junctional and AV reentrant tachycardia groups, respectively, and 83 +/- 42 ms in the ectopic atrial tachycardia group (P < 0.0000001 ectopic atrial tachycardia group vs. others). When three or more post-pacing VA intervals were obtained during the same tachycardia, a curve was constructed by plotting their values against the corresponding pacing cycle lengths. A curve could be constructed in 36% of the cases and was flat in all patients with AV junctional and AV reentry, while it was completely irregular in the ectopic atrial tachycardia group (P < 0.003). The analysis of post-pacing VA interval behaviour in response to overdrive atrial stimulation provides a rapid and reliable differentiation between supraventricular tachycardias with 1:1 AV conduction ratio during a transesophageal electrophysiological study. PMID- 9363502 TI - Population-based epidemiological study on characteristics of risk factors of hypercholesterolemia in Saudi Arabia. AB - OBJECTIVES: To study the characteristics of risk factors for hypercholesterolemia among the Saudi population. DESIGN: Population-based cross-sectional national epidemiological randomized household survey. SUBJECT: 4548 Saudi subjects, aged 15 years and above. Sample was representative and in accordance with the national population distribution with respect to age, gender, regional and residency, urban vs. rural, population distribution. MEASUREMENT: Height and weight with calculation of body mass index, blood samples were drawn and assayed for glucose and total cholesterol concentration. Hypercholesterolemia (HC) was defined: borderline high HC (5.2-6.2 mmol l-1) and high HC (> 6.2 mmol l-1). Univariate, multivariate, simple logistic, multiple logistic, odd ratio and chi-square were employed in the statistical analysis. RESULTS: The risk of developing HC increased with age by 2% and 1% for each year increase in age for borderline high HC and high HC. The risk of developing HC was significantly higher among female subjects. There was no significant relation between the spectrum of BMI group, underweight to obesity, with risk of developing borderline high or high HC. There was a significant increase in the risk of developing HC among residents of urban communities. There was no significant regional variation for risk of borderline high HC, however, there was a significant increase in the risk of developing high HC among residents of Central and Eastern regions, compared with other regions. CONCLUSION: The characteristics of risk factors for HC among the Saudi population differ in many respects from other populations. Overweight and obesity are not significant risk factors for HC. Rural communities are more at risk of HC than urban communities. The population of the Eastern and Central regions were at significantly higher risk of developing HC. The relatively recent urbanization may account for the low prevalence of HC. It may partially explain the dissociation between obesity and HC. Food habits, both in quantity and quality in rural communities in genetically predisposed homogenous populations may account for the increase in the prevalence of HC in rural communities. There is a need to propagate information about the potential health hazard of obesity and HC among Saudi communities, at large, and specifically in the Eastern and Central regions. There is a need to study the food patterns of rural communities which may explain partially the relative increase in the prevalence of HC in rural communities. PMID- 9363503 TI - Dobutamine stress echocardiography in the detection of coronary artery disease in a clinical practice setting. AB - In this prospective study, patients referred for coronary angiography for detection of disease underwent dobutamine stress echocardiography to define its value in a clinical practice setting. RESULTS: Of 219 patients studied, 170 (78%) had significant coronary artery disease. The overall sensitivity and specificity of dobutamine stress echocardiography for coronary artery disease were 82 and 65%, respectively. The sensitivity was 88% for detection of triple-vessel disease, 83% for double-vessel disease, and 74% for single-vessel disease. Positive and negative predictive values for coronary artery disease were 89 and 51%, respectively. Dobutamine stress echocardiography correctly identified only 72 of 138 patients with significant stenosis of the left anterior descending coronary artery. In 219 patients, 345 of 657 major epicardial vessels had significant disease. Dobutamine stress echocardiography could only correctly identify the vessel involved in 188. Triple-vessel disease was present in 65 patients. Dobutamine stress echocardiography correctly categorised 18% (n = 12) of these. The remainder were incorrectly classified as having double-vessel disease or single-vessel disease (n = 45), or no disease at all (n = 8). CONCLUSION: Dobutamine stress echocardiography performs well. However, lower specificity may lead to unwarranted referrals for coronary angiography, and the low NPV give false reassurance as to the absence of disease. PMID- 9363504 TI - Right ventricular cardiomyopathy: diffuse dilatation, focal dysplasia or biventricular disease. AB - Non-coronary ventricular tachyarrhythmias originating from the right ventricle are frequent events associated in many cases with structural and functional abnormalities of the right ventricle. Primary right ventricular affections such as arrhythmogenic right ventricular dysplasia and secondary right ventricular involvements such as in dilated cardiomyopathy must be distinguished. The value of conventional diagnostic procedures is undetermined. A total of 73 patients (41 males, mean age 40.6 +/- 11.4 years) with left bundle branch block ventricular arrhythmias and angiographic aspects of right ventricular outpouchings or aneurysms were divided into three groups: Group 1: diffuse right ventricular dilatation without left ventricular affection, Group 2: focal right ventricular abnormalities (dysplasia) Group 3: biventricular disease. The results of standard ECG, angiography and programmed ventricular stimulation were analysed retrospectively. Clinical monomorphic ventricular tachycardia was more often in diffuse dilatation (82%) and focal dysplasia (57%). In these two groups programmed ventricular stimulation was able to induce clinical tachycardias at a high degree (57-82%). In cases of biventricular disease cardiac arrest as the primary event without inducibility of monomorphic ventricular tachycardia was the predominant feature (44%). Standard ECG disclosed localised right precordial QRS prolongation in 'normal' QRS morphology, incomplete and complete right bundle branch block in 66 patients in all three subgroups. Other ECG findings such as left ventricular hypertrophy in four patients with heart failure and single premature beats and left bundle branch block in a patient with rapid ventricular tachycardia and ventricular fibrillation was found only in group 3 supposed to be the most heterogeneous group. In summary, angiographic classification used in this study demonstrates different morphological aspects of right ventricular cardiomyopathy with ventricular tachyarrhythmias as the major clinical aspect. High risk patients with diffuse dilatation or biventricular disease can be identified. Only patients with the angiographic aspect of focal dysplasia seem to be possible candidates for catheter ablation techniques. PMID- 9363505 TI - Percutaneous transluminal recanalization for an occluded modified Potts shunt. AB - We performed percutaneous transluminal recanalization successfully for an occluded modified Potts shunt in a 35-year-old man with pulmonary atresia and ventricular septal defect. Percutaneous transluminal recanalization deserves to be considered for occluded shunts if the duration of obstruction is short. PMID- 9363506 TI - Left atrial myxoma presenting with myocardial infarction. Case report and review of the literature. AB - Coronary artery embolization is an extremely rare and potentially lethal complication of atrial myxomas. We present a case report and a literature review of this clinical association. A 53-year-old woman presented with an acute infero lateral myocardial infarction. Coronary angiography performed 1 h after the onset of pain disclosed an abrupt stop and multiple embolization of the peripheral right coronary artery (RCA). A transthoracic echocardiographic study revealed the presence in the left atrium of an echogenic, mobile mass, compatible with myxoma. The tumour was successfully removed surgically 2 weeks later and the patient is doing well one year post operatively. PMID- 9363507 TI - Occurrence of the same peroxidative compounds in low density lipoprotein and in atherosclerotic lesions from a homozygous familial hypercholesterolemic patient: a case report. AB - Oxidative modification of low density lipoprotein (LDL) and its byproducts may play a fundamental role in atherosclerosis. We report an in vitro analysis of LDL peroxidative compounds in an homozygous familial hypercholesterolemic (HFH) patient who subsequently died. During the autopsy, we analyzed lipids extracted directly from different atherosclerotic plaques, and we also provided an immunocytochemical analysis using the specific monoclonal antibody MDA2 (directed against malondialdeyde-lysine epitopes of oxidized LDL). The results showed that the same species of peroxidative compounds were present both in LDL in vitro and in lipids extracted directly from atherosclerotic lesions. Moreover, the immunocytochemistry analysis revealed a positive staining of atherosclerotic plaques, confirming the presence of LDL oxidation-specific epitopes. Although observation of a single case is necessarily limited, our findings are consistent with the hypothesis that oxidative modification of LDL is involved in human atherogenesis. PMID- 9363508 TI - Failure of low dosage thrombolytic therapy with streptokinase to treat heparin induced thrombocytopenic-thrombotic syndrome. AB - We report the case of a 58-year-old man affected by thrombocytopenic-thrombotic syndrome induced by therapy with subcutaneous unfractionated heparin for superficial phlebitis of the left inferior limb. Thrombolytic therapy with low dosage streptokinase, reported as successful in a previous case described by other authors, was inefficacious and the patient's outcome was unfavourable. Thrombocytopenic-thrombotic syndrome may be a dreadful and often deadly consequence of heparin therapy, and its treatment needs investigation, owing to currently broadening use of anticoagulant treatment with both unfractionated and low molecular weight heparins. PMID- 9363509 TI - Epicardial pacing using a pacemaker with Autocapture algorithm in an infant. PMID- 9363510 TI - Breast cancer risk and alcohol consumption: results from a large case-control study. AB - BACKGROUND: Alcohol use is associated with breast cancer in many epidemiological studies. Most, however, have measured risk from recent consumption patterns, and only a few include analyses for duration of drinking or age that a woman started to drink. The authors studied the effect of these variables, as well as of recent alcohol consumption patterns, on breast cancer risk. METHODS: Data from a large case-control study conducted in Long Island, New York from 1 January 1984 to 31 December 1986 were used. A total of 1214 women aged 20-79 years with incident breast cancer were interviewed. A control was selected for each case from driver's license files, and matched on age and county of residence. Alcohol consumption was measured as: ever versus never, grams of alcohol per day, age started drinking, and total years drinking. RESULTS: After adjustment for breast cancer risk factors, the odds ratio for ever versus never drinking was 1.40 (95% confidence interval [CI] 1.09-1.79); odds ratios for > 0-5 and > or = 5 grams of alcohol use per day, as compared to nondrinkers, were 1.29 (95% CI: 1.00-1.65) and 1.46 (95% CI: 1.13-1.89), respectively. Age when drinking began was not related to breast cancer risk, but the greater the total years of drinking, up to 40 years (odds ratio 1.48, 95% CI: 1.13-1.93), the greater the risk. However, when grams per day and duration of drinking were simultaneously included in the multivariate model, duration was not important as a risk factor. This suggests that intensity of drinking may be the important factor for breast cancer risk. After covariate adjustment, risk from alcohol intake did not differ between pre- and postmenopausal women. PMID- 9363511 TI - Estimation and projections of colorectal cancer trends in Italy. AB - BACKGROUND: Occurrence of and prognosis for tumours of the colon and rectum are thought to be changing rapidly due to simultaneous changes in risk factor prevalence, early diagnosis and treatment. In this paper time trends of morbidity, survival and mortality for colorectal cancer during the period 1970 1990 are estimated and analysed. METHODS: Mortality trends were obtained from official death certificates. Relative survival rates were computed from population-based cancer registries. Incidence and prevalence rates were estimated from mortality and survival data. RESULTS: Incidence rates were increasing during the period considered, with a lower rate of increase for the youngest birth cohorts. Relative survival rates of both colon and rectum cancers were higher for women, and for younger age groups, and were positively associated with period of diagnosis. No significant survival difference among the cancer registries used was found. A total of about 155,000 prevalent cases, 40% of which had been diagnosed > or = 7 years before, were estimated in the Italian population for the year 1990. Mortality rates were slightly increasing for men and stable for women. Projections of colorectal cancer trends to the year 2000 indicate major expected rises in both incidence and prevalence. CONCLUSION: Colorectal cancer represents a problem of growing impact for health services in Italy. This conclusion can probably be extended to many developed countries. PMID- 9363513 TI - Non-smoker lung cancer deaths attributable to exposure to spouse's environmental tobacco smoke. AB - BACKGROUND: The causal relationship between environmental tobacco smoke (ETS) and lung cancer is established; however, the magnitude of the risk is not known. Therefore, it is conceivable that ETS is responsible for a number of lung cancer deaths because of the large number of smokers and the widespread presence of ETS. We estimated the number of lung cancer deaths occurring in 1990 in the European Union (EU), attributable to ETS generated by a spouse. METHODS: In each country and for each sex, we used the proportion of smokers and of married people in 1970 to estimate the number of lung cancer deaths not attributable to tobacco smoking occurring in married people, assuming a relative risk (RR) for active smoking equal to 10. We then assumed a prevalence of smoking among these deaths equal to the population at large, and estimated the number of deaths attributable to ETS based on an RR for ETS of 1.3. Additional analyses were carried out assuming different values of RR for smoking and exposure to spouse's ETS. RESULTS: Based on our best assumptions, we calculated that 1146 (839 females, 307 males) lung cancer deaths were attributable to exposure to spouse's ETS in the EU in 1990. All the hypotheses tested resulted in not less than several hundred deaths. CONCLUSION: Regardless of the limitations of this exercise, our results suggest that exposure to spouse's ETS represents a relatively important public health problem in the EU. PMID- 9363512 TI - Vasectomy and prostate cancer: a case-control study in India. AB - BACKGROUND: The role of vasectomy in the development of prostate cancer remains controversial. In particular, there has been concern about detection bias and confounding in the previously published epidemiological studies examining this hypothesis. With the goal of minimizing detection bias, we have evaluated the relation between vasectomy and prostate cancer in a population without routine prostate cancer screening. METHODS: A case-control study consisting of 175 prostate cancer cases and 978 controls with cancer diagnoses other than prostate cancer was conducted at hospitals covered by the Bombay Cancer Registry in Bombay, India. History of vasectomy, demographic, and lifestyle factors were obtained by structured interview. Multiple logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Standardizing by age, 8.7% of cases and 8.3% of controls had had a vasectomy. The OR for prostate cancer comparing men who had had a vasectomy to those who did not was 1.48 (95% CI: 0.80-2.72) controlling for age at diagnosis, smoking status, alcohol drinking, and other demographic and lifestyle factors. Risk of prostate cancer associated with vasectomy appeared to be higher among men who underwent vasectomy at least two decades prior to cancer diagnosis or who were at least 40 years old at vasectomy. CONCLUSIONS: Although not statistically significant, the results of this hospital-based case-control study are consistent with the hypothesis of a positive association between vasectomy and prostate cancer. Because routine prostate cancer screening is not common in this population, detection bias was unlikely to account for this association. PMID- 9363515 TI - Comparing dietary recall data for mothers and children obtained on two occasions in a case-control study of environmental factors and childhood brain tumours. AB - BACKGROUND: Food frequency questionnaires (FFQ) have been widely used in epidemiological studies of dietary factors, despite persistent questions about the quality of the data they generate. To address concerns about the influence of disease status on dietary recall, we examined the temporal consistency of dietary recall data obtained in a case-control study of environmental factors and childhood brain tumours. METHODS: On two occasions separated by approximately 4.5 years, the mothers of children with brain tumours and healthy matched controls were asked about their diets during pregnancy and their children's diets prior to diagnosis. Forty-five case and 60 control mothers completed both FFQ for themselves and/or their children. Daily dietary intakes of substances related to dietary N-nitroso compounds were estimated from the responses to each of the questionnaires and compared. The dietary intakes of the cases were also compared to their matched controls. RESULTS: The changes in estimated dietary intakes from the first to the second questionnaire administration were similar in both groups of mothers, indicating negligible case-control differences in healthy individuals recalling their own diets. Control mothers reported for their children a higher intake of the index foods on the second questionnaire than on the first while estimated intakes for the case children were lower the second time compared to the first. Significant case-control differences among the children were seen for the majority of dietary components examined. CONCLUSIONS: The results suggest that the magnitude and direction of errors in dietary recall data can vary by disease status, and further suggest that reliance on retrospective reports of children's diets may be inappropriate in a case-control study. PMID- 9363514 TI - Non-Hodgkin's lymphoma: time trends for incidence and survival in Cote-d'Or, France. AB - BACKGROUND: A generally reported increased incidence of non-Hodgkin's lymphomas (NHL) and a recent evolution in treatment strategies, as well as several clinical trials suggesting improved survival, have prompted this study to evaluate time trends in incidence and prognosis of NHL. METHOD: NHL recorded by the population based Registry of Hematopoietic Malignancies in Cote-d'Or (France) were considered over three 4-year periods from 1980 to 1992. A multivariate survival analysis was carried out in terms of both crude and relative survivals. RESULTS: Overall incidence, increased over the 12 years considered, by an average of 6.8% per annum (P < 0.05). Only two cases of AIDS-related NHL were registered during this period. NHL incidence has increased slightly more for males than for females, further widening the gap in incidence between the sexes. In terms of histological grade the increase in incidence was more pronounced for low-grade and high-grade NHL than for intermediate-grade NHL. The overall 5-year relative survival rate was 69.3%. In multivariate relative survival analysis, neither sex, age, period of diagnosis nor place of hospitalization were significant prognostic factors. Only place of residence, with RR 2.2 (1.41-3.42) for people living in rural areas compared to urban areas and histological type, according to the working formulation with RR 3.8 (2.22-6.61) for high-grade tumours compared to low-grade tumours, remained informative for prognosis. CONCLUSIONS: Although incidence of NHL has increased in Cote-d'Or, this trend has remained independent of the AIDS epidemic. Contrary to the findings of clinical trials, the patients' survival in this population-based series has not been shown to have improved over the study period. PMID- 9363516 TI - Twelve-year results of the Coronary Risk Factor Study (CORIS). AB - BACKGROUND: After 4 years a coronary heart disease risk factor intervention programme produced equally large and significantly reduced risk profiles in two intervention towns compared with a control town. Intervention effects through community participation were assessed after cessation of the active intervention programme. The impact of secular trends was assessed in the control town and in two previously unstudied towns. METHODS: Cross-sectional surveys were done in a random sample of 1620 participants aged 15-64 years in the three original towns 12 years after the initial quasi-experimental study. Two years later 327 subjects, aged 35-44 years, were studied in the original control town and in two non-intervention towns. Risk factor knowledge, smoking and medical histories were determined by questionnaire. Blood pressure, anthropometry and blood lipids were recorded. Data were compared across towns, and with previous surveys. RESULTS: At 12 years the low intensity intervention town maintained a significantly better risk factor profile than the control town, while the high intensity intervention town now matched the control town. No differences in risk factor profiles were found between the control town and the two new towns. Deaths from coronary heart disease and strokes showed a downward trend in the study area. CONCLUSIONS: Outcome suggests large ongoing secular trends during the study could have overtaken the intervention effects in the high intensity town, but not in the low intensity intervention town, which showed an advantage over the control town. These results support the effectiveness of media-based, long term health promotion strategies to reduce cardiovascular disease risk profiles. PMID- 9363517 TI - Cigarette smoking and thyroid hormone levels in males. AB - BACKGROUND: Cigarette smoking has been linked to thyroid disease, although studies of this problem have not shown consistent affects, with some studies linking smoking to increased thyroid hormone levels, and others to decreased thyroid hormone levels. METHODS: We performed a secondary analysis of information collected from 4462 Vietnam-era male US Army veterans aged 31-49 years who participated in the Vietnam Experience Study in 1985-1986. The study group consisted of 1962 current smokers and 2406 current non-smokers who had no thyroid abnormalities on physical examination, no current use of thyroid medicine, and no history of thyroid disease. RESULTS: We found that current smokers have higher thyroxine levels and lower thyroid stimulating hormone levels than never smokers and former smokers. The higher thyroxine levels that we detected in smokers, compared to non-smokers, diminished when we controlled for thyroxine-binding globulin and testosterone. We also found that heavy smokers had a smaller increase in thyroxine levels than did light smokers, when compared to non smokers. CONCLUSIONS: Our findings suggest at least two distinct mechanisms for the effect of tobacco smoke on thyroid function; one related to higher levels of thyroxine-binding globulin and testosterone among smokers compared to non-smokers and another related to higher levels of thyrotoxins in tobacco smoke in heavy smokers compared to light and moderate smokers. PMID- 9363518 TI - Maternal smoking during pregnancy, urine cotinine concentrations, and birth outcomes. A prospective cohort study. AB - BACKGROUND: Most studies of the reproductive consequences of cigarette smoking base exposure on self-reported smoking habits. This study examines the relationship of birth outcomes to the timing and intensity of maternal active and passive smoking estimated both from self-reports and from cotinine concentration in maternal urine during early, middle, and late gestation. METHOD: This cohort study included 740 white and Hispanic women who obtained antenatal care at the East Boston Neighborhood Health Center between 1986 and 1992. At each antenatal visit, information on maternal active and passive smoking was obtained by a detailed questionnaire, and by measurement of urine cotinine concentrations. Infant birth outcomes were obtained from hospital records. Multiple linear regression was used to evaluate antenatal smoking variables on birth outcomes, with adjustment for maternal demographic characteristics, reproductive history, alcohol use, maternal weight and height, and infant gender. RESULTS: The percentage of mothers who ever smoked cigarettes during pregnancy was 55.5% for white and 10.2% for Hispanic women. A significant inverse exposure-response relationship between cotinine concentration in maternal urine and infant size at birth was demonstrated. However, the relationship was less clear between maternal self-reported smoking status and these outcomes. For the entire gestation, a 1000 ng increase in mean urine cotinine concentration was associated with a 59 +/- 9 g reduction in birthweight, a 0.25 +/- 0.05 cm reduction in length, and a 0.12 +/- 0.03 cm reduction in head circumference, respectively. For maternal passive smoking, the much smaller magnitude of effect precludes firm conclusions. CONCLUSIONS: These data suggest that preventing and reducing active maternal smoking during pregnancy may have a beneficial impact on infant size at birth. PMID- 9363519 TI - Stroke morbidity in professional drivers in Denmark 1981-1990. AB - BACKGROUND: Little has been published on the possible associations between professional driving and stroke although it is well documented from several countries that professional drivers have an increased risk of coronary heart disease. There are common aetiologic factors for coronary heart disease and stroke. The aim of the present study is to estimate the risk of stroke among professional drivers in 13 male and 4 female groups defined by employment status and industry. METHODS: Cohorts of all gainfully employed 20-59 year old Danes were formed to compare Standardized Hospitalization Ratios (SHR) for stroke between occupational groups. The follow-up period was 10 years. RESULTS: A consistent pattern of high risk was found for all groups of male drivers except removal men. The group 'All drivers' had an increased risk of stroke SHR = 130 for men (95% confidence interval [CI]: 123.6-137.5) and SHR = 148 for women (95% CI: 113.9-191.4). Standardization for employment status reduced the risks but they were still found to be statistically significantly increased: SHR = 114 for men (95% CI: 108.2-120.4) and SHR = 130 for women (95% CI: 100.0-168.0). CONCLUSIONS: Professional driving is associated with an increased risk of stroke morbidity. PMID- 9363520 TI - Prevalence of chronic diseases in older Italians: comparing self-reported and clinical diagnoses. The Italian Longitudinal Study on Aging Working Group. AB - BACKGROUND: The Italian Longitudinal Study on Aging (ILSA) evaluates the rates of diabetes, cardiovascular and neurological disorders in a random sample of 5632 Italians aged 65-84 years. METHODS: The ILSA has two components: a first screening phase administered to all participants, that includes a personal interview, physician examination, laboratory and diagnostic tests, and a second phase, consisting of the clinical confirmation of suspected cases by a specialist. RESULTS: Prevalence rates were significantly higher among men for myocardial infarction (10.7% versus 4.8%), cardiac arrhythmia (25.1% versus 20.3%) and peripheral artery disease (8.1% versus 5.2%), and among women for hypertension (67.3% versus 59.4%), heart failure (7.3% versus 5.4%) and dementia (7.2% versus 5.3%). No gender difference was found for stroke, angina, diabetes, Parkinsonism and distal symmetric neuropathy. Unreported diagnoses accounted for 85% of cases of distal symmetric neuropathy, for more than half the cases of cardiac failure, for 40% of cases of angina, and for more than one-third of cases arrhythmia, myocardial infarction, peripheral artery disease, hypertension, Parkinsonism. Data from the phase 1 interview showed substantial overreporting for myocardial infarction, peripheral artery disease, diabetes, and stroke. CONCLUSIONS: The authors conclude that self-reported information would lead to inaccurate estimates of prevalence rates suggesting the need for including the clinical ascertainment in any population-based epidemiological study. PMID- 9363521 TI - Change in incidence of Crohn's disease and ulcerative colitis in Denmark. A study based on the National Registry of Patients, 1981-1992. AB - BACKGROUND: The incidence of inflammatory bowel disease (IBD) in Denmark is considered to be among the highest in Europe. However, the diseases are relatively rare and therefore it would be useful if existing registers could replace ad hoc examination in the surveillance of IBD. METHODS: The present study used the Danish National Registry of Patients to estimate incidence rates, 1981 1992. RESULTS: A total of 2806 patients with Crohn's disease (CD) and 8125 with ulcerative colitis (UC) were identified. The mean incidence for CD was 4.6 (5.4 for women and 3.7 for men) per 100,000 per year, with a peak incidence in younger women. The incidence increased in most age groups with the highest increase in older women. The mean incidence for UC was 13.2 (13.4 for women and 13.0 for men) per 100,000 per year, with the highest incidence in older men. A decreasing tendency in the incidence was present in most age groups. CONCLUSIONS: The present study found an increasing incidence for CD and a stable incidence with a tendency to decrease for UC. Comparison with ad hoc studies indicates that it is possible to use the Danish National Registry of Patients in the surveillance of IBD, especially for CD. PMID- 9363523 TI - Stressful life events and risk of symptomatic kidney stones. AB - BACKGROUND: It has been reported that a substantial proportion of cases of hypercalciuria and nephrolithiasis are idiopathic. Several studies suggested that stressful life events increase lithogenic urinary constituents (calcium, oxalate and uric acid). OBJECTIVE: To test the hypothesis that there is an association between stressful life events and symptomatic kidney stone. METHODS: A case control study of 200 symptomatic kidney stone cases and 200 matched controls was designed to test the hypothesis. In this study, the stressors include those life events that the subjects perceived as highly stressful and inflicted upon them an intense emotional impact with apprehension and distress for at least one week in duration. RESULTS: Ten of eleven (91%) categories and 41 of 60 (68%) subcategories of stressful events occurred more frequently among cases than controls. Eighteen stressful events had odds ratios of 1.5 or greater. Of the seven significant (P < 0.05) variables that were entered into a multivariate logistic regression model, the following three remained statistically significant between cases and controls: annual family income (lower for cases); stressful morgage problems; and emotional life events. CONCLUSION: The overall prevalence rate of stressful life events was significantly (P < 0.00001) higher among cases than controls. The data support the hypothesis that there is an association between stressful life event(s) and symptomatic kidney stones. PMID- 9363522 TI - Comparison of information on occupation and lifestyle habits obtained from European man-made vitreous fibre production workers and their relatives. AB - BACKGROUND: Studies of the aetiology of fatal diseases often rely on data obtained from relatives, which can cause loss of precision and introduce bias. We assessed the quality of such information on demographics, occupation, smoking and alcohol habits. METHODS: We compared contemporary interviews, based on a structured questionnaire, with male workers from the man-made vitreous fibre production industry in four European countries and their relatives. The participation rate was 63% (74 pairs of workers and relatives). RESULTS: Only minor differences in the ability to answer the questions appeared among workers and relatives, except for specific occupational questions. There was moderate to excellent agreement for demographics, residential and work history (kappa or intraclass correlation range: 0.44-0.98). For smoking habits, beer and wine consumption the agreement was good to excellent (range: 0.59-0.99). In particular, number of different residential areas, jobs, industries, and duration of wine drinking were significantly underreported by the relatives. No general determinant for reduced agreement appeared. CONCLUSIONS: In general, the quality of information obtained from relatives appeared good. However, information on specific occupational exposures may be improved by supplementing the information from relatives with details obtained from colleagues, occupational hygiene experts or occupation-exposure matrices. PMID- 9363524 TI - Differential features of motor neuron disease mortality in Spain. AB - BACKGROUND: The objective of this study was to describe the temporal and spatial patterns of motor neuron disease (MND) in Spain. METHODS: We studied data where MND was stated as the principal cause of death in official statistics from Spain. Time trends were analysed for age-, sex-specific and age-adjusted rates for the period 1951-1990. Age-adjusted mortality and relative risk, obtained by Poisson regression adjusting for age, were calculated for each province from deaths during the period 1975-1988. Maps were constructed using log transformed rates. Statistical significance of spatial aggregation was assessed using the Ohno et al. test. RESULTS: The 1951-1990 mortality rate, age- and sex-adjusted to the European population, for the population aged > or = 40 years was 1.49 per 100,000; 1.90 and 1.21 for males and females respectively. In general, mortality increased with age. Age-adjusted rates rose until 1960, dropped by 70% during the 1960s and declined slightly over the 1951-1990 period as a whole. From 1970 onwards MND mortality rose evenly, particularly in the 60-69 age group. A North South gradient was suggested for both sexes with statistically significant clustering in the Northern coastal regions and--for males alone--in the Midwest provinces. CONCLUSIONS: Mortality from MND in Spain displayed a magnitude and recently rising temporal trend similar to that described in several other countries. Specific traits were: a decrease during the 1960s, which has been described for Japan only, as well as spatial heterogeneity and a predominant recent increase among the 60-69 age group. The determinants of these unusual MND mortality patterns are unknown. PMID- 9363525 TI - Injuries in a problematic socioeconomic context: a population-based study in Reunion, Indian Ocean, 1993-1994. GEAR. Groupement d'Etude sur les Accidents a la Reunion. AB - BACKGROUND: This study was designed to estimate the incidence and describe the characteristics of injuries during a one-year period in the French island of Reunion, Indian Ocean, a defined geographic population with socioeconomic problems. METHODS: Cases were injuries from accidents (unintentional injuries), self-inflicted injuries (suicides and attempted suicides), or injuries purposely inflicted by other people, that resulted in hospital admission or death. Patients and injury characteristics were recorded prospectively, alternately every other week, in all emergency rooms on the island; all death certificates were studied. RESULTS: The overall annual incidence of injuries was 1578 per 100,000 residents. The three main causes of injury were (i) falls on the same level (23.6%), (ii) poisoning (23.0%) and (iii) traffic accidents (21.5%). Of the traffic accident cases, 44% were motorcyclists (mostly mopeds) and more than half of the cases were 15-25 years old. Suicides and attempted suicides accounted for 80.9% of poisonings, 35.5% of immediately fatal injuries, and 19.6% of non-fatal injuries. Homicides and assaults accounted for 8.3% of all injuries. The employment rate was lower for injured patients than in the total Reunion population (standardized ratio for males: 74; P < 0.001). Half of the injured hospitalized patients had an Injury Severity Score < 5 and 8 days after hospitalization, 83.5% of patients had returned home. CONCLUSION: Injury epidemiology may be affected by different demographic, socioeconomic, cultural and geographical factors. Targeted studies are therefore necessary to guide injury prevention measures. PMID- 9363526 TI - Sampling designs for xerophthalmia prevalence surveys. AB - BACKGROUND: The purpose of this study was to estimate the bias and design effects associated with the Expanded Program on Immunization's (EPI) sampling design when estimating xerophthalmia prevalence, and to estimate the savings associated with EPI in terms of distance travelled within selected clusters. METHODS: Computer simulation of the EPI sampling strategy was done using maps from a xerophthalmia survey of 40 wards in Sarlahi district, Nepal. Samples of fixed cluster sizes of 7, 10, 15, 20 and 25 were compared. The estimated prevalence using the EPI design was compared with the true prevalence in the 40 wards to estimate the bias. The design effect was estimated by taking the ratio of the variance under EPI sampling to that of stratified random sampling (SRS) with fixed cluster sizes. The EPI was also modified by increasing the distance between selected houses from nearest neighbour to skipping 1-4 houses between selected ones. The difference between the distance travelled within clusters using SRS compared with EPI was weighed against the bias and increased variance. RESULTS: The prevalence of xerophthalmia was 2.8%. The EPI design overestimated xerophthalmia prevalence by between 0.27% and 1.16%. The design effects of EPI cluster sampling within wards varied between 0.73 and 1.35. Neither the bias nor the design effect was related to distance between households or cluster size. Distance travelled within wards was always less for EPI designs with cluster sizes of 7 or 10. There was no saving in terms of distance travelled for designs with cluster sizes from 15 to 25 if there were two or more houses between selected ones. For fixed cluster sizes of 15 or fewer, the EPI sampling design using nearest or next nearest neighbours is a better choice than SRS in terms of minimizing the distance travelled and the mean square error. CONCLUSIONS: The choice of an optimum method would need to account for the density of clusters and difficulty of travel between clusters, as well as the costs of travel within clusters. Based on certain assumptions, EPI with 15 children per cluster would be favoured over examining all children in selected wards unless the travel time between wards was more than 2 days. PMID- 9363527 TI - Rapid assessment of prevalence of cataract blindness at district level. AB - AIM: To find an optimal cluster size and number of clusters for a reasonable estimate of the prevalence of cataract blindness in people aged > or = 50 years in 19 rural districts of a state in India. MATERIALS: Cluster sampling methodology was used in 19 rural districts of Karnataka State, India. In each district, 15 clusters were randomly selected and 90 people aged > or = 50 years were examined in each cluster. As a result the visual acuity and lens status of a total of 22,218 people were assessed. METHODS: For each district, the design effect for cluster size ranging from 20 to 90 was calculated and the optimal cluster size and the required number of clusters to achieve an accuracy of 1% errors and 80% confidence was assessed. RESULTS: The age and gender adjusted prevalence of cataract blindness varied from 1.58% to 7.24%, which justifies district level surveys. The design effect is nearly 1.5 for clusters of sizes 30 and 40. With an average prevalence of 4.93% with 1% error and 80% confidence level, the optimal number of clusters is 37 and 28 for a cluster size of 30 and 40 respectively and the average sample size for a district around 1100. CONCLUSIONS: Rapid assessments for cataract blindness in those aged > or = 50 years can be conducted at district level in India with existing resources and at affordable costs. These provide reliable data, essential for effective monitoring and planning. Other parameters, for instance, surgical coverage can also be assessed. The availability of standardized software for data entry and analysis and strict adherence to survey procedures is essential. PMID- 9363528 TI - Characteristics of non-responders and the impact of non-response on prevalence estimates of dementia. AB - BACKGROUND: Differential distributions of sociodemographic characteristics and cognitive impairment in responders and non-responders may result in a biased prevalence estimate of dementia based on responders only. METHODS: Responders (n = 2191) to a cross-sectional, two-stage community study were compared with regard to sociodemographic characteristics and cognition with three subgroups of non responders: (A) subjects who refused to participate (n = 369), (B) subjects who were too ill or who had died prior to the screening (n = 72) and (C) subjects who had moved out of the study region or were not traceable (n = 23). Prevalence estimates specific for age and housing situation in responders and physicians' ratings of cognitive impairment were used to estimate the prevalence of dementia among non-responders. RESULTS: Group A differed from responders in age and housing situation, group B in age, housing and cognition, and group C only in age. Separate prevalence estimates of dementia based on age, housing and cognition yielded figures for group A between 4.9% and 7.2%, for group B between 13.1% and 19.1%, and for group C between 2.6% and 4.2%. Joined with the prevalence rate among responders (6.5%) the best possible point estimate of the prevalence of dementia in the target population lies between 6.4% and 6.9%, i.e. within the 95% confidence interval (CI) of the prevalence among responders (5.4 7.5%). CONCLUSIONS: Although in this study non-response had no important influence on the overall prevalence, the findings among the distinct non-response subgroups point to the importance of describing non-response sociodemographically as well as in terms of the study objective. The authors recommend that non responders are categorized into distinct groups based on the reason for non response. PMID- 9363529 TI - Does psychological distress predict disability? AB - STUDY OBJECTIVE: To evaluate psychological distress as a predictor of disability due to common chronic disorders. STUDY POPULATION AND METHODS: A 10-year follow up study was carried out among a representative cohort (N = 8655) of 18-64 year old Finnish farmers, who had participated in a health survey in 1979 and were able to work at baseline. A record linkage with the nationwide register of the Social Insurance Institution was made to identify disability pensions granted between 1980 and 1990 in the cohort. The medical certificates of 1004 (11.6%) prematurely retired farmers were reviewed to confirm and classify disabling conditions. A sum score based on self-reports of 11 symptoms at the baseline was used as a measure of psychological distress. RESULTS: After adjustment for age, sex, smoking and body mass index, the cause-specific relative risks (RR) (95% confidence intervals [CI]) of disability in the highest quartile of the psychological distress score as compared with the lowest quartile were for myocardial infarction 2.34 (95% CI: 1.17-4.69), for depression 2.50 (95% CI: 1.09 5.72), for neck-shoulder disorders 1.98 (95% CI: 1.26-3.11), for unspecified low back disorders 1.76 (95% CI: 1.24-2.49), for knee osteoarthritis 1.55 (95% CI: 0.91-2.63) and for trip osteoarthritis 0.89 (95% CI: 0.42-1.85). The corresponding RR for overall disability was 1.76 (95% CI: 1.44-2.14) in the highest quartile of psychological distress score as compared with the lowest quartile. CONCLUSIONS: Psychological distress is an independent risk factor for disability. Its predictive significance varies between disorders leading to functional deterioration. The association mechanisms are likely to vary from one disorder to another. PMID- 9363530 TI - Bias in diet assessment methods--consequences of collinearity and measurement errors on power and observed relative risks. AB - BACKGROUND: If several risk factors for disease are considered in a regression model and these factors are affected by measurement errors, the observed relative risk will be attenuated. In nutritional epidemiology, several nutrient variables show strong correlation, described as collinearity. The observed relative risk will then depend not only on the validity of the chosen diet assessment method but also on collinearity between variables in the model. METHODS: The validity of different diet assessment methods are compared. The correlation coefficients between common nutrients and foods are given using data from the Malmo Food Study. Intake of nutrients and foods were assessed with a modified diet history method, combining a 2-week food record for beverages and lunch/dinner meals and a food frequency questionnaire for other foods. The study population comprised 165 men and women aged 50-65 years. A multivariate logistic regression model is used to illustrate the effect of collinearity on observed relative risk (RRo). RESULTS: A moderate to high correlation between risk factors will substantially influence RRo even when using diet assessment methods with high validity. Methods with low validity might even give inverse RRo. CONCLUSION: It is stressed that caution must be exercised and only a selected number of variables should be included in the model, especially when they are highly intercorrelated, since RRo might be severely biased. PMID- 9363531 TI - A review of data-derived methods for assigning causes of death from verbal autopsy data. AB - BACKGROUND: Verbal autopsy (VA) is an indirect method for estimating cause specific mortality. In most previous studies, cause of death has been assigned from verbal autopsy data using expert algorithms or by physician review. Both of these methods may have poor validity. In addition, physician review is time consuming and has to be carried out by doctors. A range of methods exist for deriving classification rules from data. Such rules are quick and simple to apply and in many situations perform as well as experts. METHODS: This paper has two aims. First, it considers the advantages and disadvantages of the three main methods for deriving classification rules empirically; (a) linear and other discriminant techniques, (b) probability density estimation and (c) decision trees and rule-based methods. Second, it reviews the factors which need to be taken into account when choosing a classification method for assigning cause of death from VA data. RESULTS: Four main factors influence the choice of classification method: (a) the purpose for which a classifier is being developed, (b) the number of validated causes of death assigned to each case, (c) the characteristics of the VA data and (d) the need for a classifier to be comprehensible. When the objective is to estimate mortality from a single cause of death, logistic regression should be used. When the objective is to determine patterns of mortality, the choice of method will depend on the above factors in ways which are elaborated in the paper. CONCLUSION: Choice of classification method for assigning cause of death needs to be considered when designing a VA validation study. Comparison of the performance of classifiers derived using different methods requires a large VA dataset, which is not currently available. PMID- 9363532 TI - The effect of misclassification error on reported cause-specific mortality fractions from verbal autopsy. AB - BACKGROUND: Verbal autopsy (VA) studies are important for measuring cause specific mortality in areas where medical certification of cause of death is uncommon. This paper explores the effects of misclassification errors on the results of verbal autopsy studies, and recommends ways to take misclassification errors into account in the interpretation of results. METHODS: Mathematical formulae are derived for determining the size and direction of the error in cause specific mortality estimates based on VA studies caused by misclassification. The levels of sensitivity and specificity found in currently available validation studies for childhood VA are examined. RESULTS: There can be substantial errors in the estimates of the cause-specific mortality fraction derived from VA studies. The cause-specific mortality fraction itself has an important influence on the size of the error for given levels of sensitivity and specificity, and when the cause-specific mortality fraction is small, the size of the error depends more on specificity than on sensitivity. CONCLUSION: Despite its drawbacks VA seems to be the most promising way of establishing cause of death when most deaths take place at home without medical attention. However, more validation studies on standardized instruments are required in order to collect information about sensitivity and specificity and subsequently improve the design of the instrument. At the same time, analysts need to take misclassification errors into consideration in ways outlined in this paper. PMID- 9363533 TI - The effect of different sensitivity, specificity and cause-specific mortality fractions on the estimation of differences in cause-specific mortality rates in children from studies using verbal autopsies. AB - BACKGROUND: Verbal autopsies (VA) are increasingly being used in developing countries to determine causes of death, but little attention is generally given to the misclassification effects of the VA. This paper considers the effect of misclassification on the estimation of differences in cause-specific mortality rates between two populations. METHODS: The bias in the percentage difference in cause-specific mortality between two populations has been explored under two different models: i) assuming that mortality from all other causes does not differ between the two populations; ii) allowing for a difference in mortality from all other causes. The bias is described in terms of the sensitivity and specificity of the VA diagnosis and the proportion of mortality due to the cause of interest. Methods for adjustment of sample size and adjusting the estimate of effect are also explored. RESULTS: The results are illustrated for a range of plausible values for these parameters. The bias is more extreme as both sensitivity and specificity fall, and is particularly affected even by a small loss of specificity. The bias also increases as the proportion of all deaths due to the cause of interest decreases, and is affected by the size of the true change in mortality due to the cause of interest relative to the change in mortality from other causes. Calculations from existing data suggest prohibitively large sample sizes may often be required to detect important differences in cause-specific mortality rates in studies using existing VA. CONCLUSIONS: Highly specific VA tools are needed before observed differences in cause-specific mortality can be interpreted. Loss of power due to misclassification may obscure real differences in cause-specific mortality. PMID- 9363534 TI - Multiple imputation method for estimating incidence of HIV infection. The Multicenter Prospective HIV Study. AB - BACKGROUND: CD4+ T-lymphocyte (CD4) and platelet counts are good predictors of the 'maturity' of HIV infection and can be used to impute the date of infection/seroconversion in individuals for whom this date is unknown. METHODS: Data from the Italian Seroconversion Study were used to develop a Weibull regression model for time since seroconversion as a function of the haematologic markers. The model was used to impute time since HIV infection/seroconversion in individuals from a prevalent cohort, recruited through the Lazio regional HIV surveillance system. RESULTS: The range of the imputed calendar times of infection/seroconversion in 2599 HIV prevalent individuals was 1972-1992; the earliest seroconversions occurred among injecting drug users (IDU). The peak of incidence was reached in 1986 with 340 seroconversions. Among males, the estimated median time from seroconversion to HIV diagnosis was shorter in IDU (30 months) as compared to non-IDU (36 months). This difference was smaller for females (26.6 versus 28.4 in IDU and non-IDU, respectively). CONCLUSIONS: This method permits the estimation of population-based curves of HIV incidence, using data from surveillance. The results support the hypotheses of an early spread of the epidemic among IDU in the Lazio region, and of shorter lead times in this population. PMID- 9363536 TI - Objective assessment of risk maps of tick-borne encephalitis and Lyme borreliosis based on spatial patterns of located cases. AB - BACKGROUND: Clusters of infection can indicate the underlying risk pattern of an endemic disease. Retrospective epidemiological data have been used to map the risk of tick-borne encephalitis (TBE) and Lyme borreliosis (LB) in the Central Bohemian region of the Czech Republic. METHODS: Both reported places of infection and patients' residences were entered in a geographical information system; their distance distribution and census data were used to model density of the population at risk. Point-pattern analysis and non-parametric kernel smoothing of points of infection were applied to compute the risk maps. Tick flagging and direct immunofluorescence assay were used to probe true LB-risk in the field. RESULTS: Tick-borne encephalitis infections proved to be more clustered than those of LB which was widespread; however, the most prominent clusters of both diseases largely correspond to each other. The estimated LB risk correlated well with tangible disease challenge as assessed from the tick abundance and Borrelia infection rates at 15 selected localities surveyed annually. CONCLUSION: The risk of LB is widely and smoothly distributed over the area studied, apparently following tick habitats wherever they occur, while TBE is confined to a subset of these locations. PMID- 9363535 TI - Risk factors for the development of non-response to first-line treatment for tuberculosis in southern Vietnam. AB - BACKGROUND: Acquired resistance to standard chemotherapy for tuberculosis (TB) is an increasing problem worldwide. Vietnam has one of the highest incidences of TB and also has a large population of potential migrants to other countries. Since 1979 the International Organisation for Migration (IOM) has been running a supervised programme of TB treatment for intending migrants from Vietnam where few facilities for bacteriological culture and sensitivity testing exist. This study aimed to assess the most important factors for predicting non-response to first-line treatment as treatment starts and whether any further indicators occur during the course of treatment which may enable more accurate prediction of non response. METHODS: In all, 130 subjects failing to respond to first-line therapy (cases) between 1990 and 1995 were compared with 673 subjects who responded to therapy (controls) on various demographic and clinical characteristics using logistic regression to create a prognostic index. Variables analysed included the patient history of past TB treatment, weight, age, sex and radiological and bacteriological findings. All subjects also tested negative for HIV status. RESULTS: The chief markers of successful response were x-ray signs and degree of sputum smear positivity. These markers provided a prognostic index with an optimal cutoff providing about 70% sensitivity and 80% specificity. Incorporating further measures obtained through the first 3 months of treatment improved the sensitivity to 80%. CONCLUSION: While this study enabled prediction of the majority of subjects failing to respond to first-line therapy, other factors need to be assessed before recommendations for altering treatment regimens can be made. The prognostic index could be useful in assessing subjects for closer supervision. PMID- 9363537 TI - Mercury toxicity associated with a beauty lotion, New Mexico. PMID- 9363538 TI - Measuring outcomes in genitourinary medicine: an introduction. PMID- 9363540 TI - The oral manifestations of HIV infection. PMID- 9363539 TI - Key issues in outcomes measurement. AB - Exploring and monitoring outcomes within routine clinical practice is central to high quality patient care. It is however a complex and challenging task. Multiple interests in outcomes information are apparent and different perspectives on what counts as an 'effective' intervention or 'successful' outcome. The paper provides insight into ways to explore and monitor the desired outcomes of key participants to the health care process. In particular, it outlines the approach of the outcomes grid, and applies this to services for genitourinary medicine. PMID- 9363541 TI - The prevalence of serological markers for syphilis amongst a sample of Spanish prostitutes. AB - The results of a multicentre study of 1668 Spanish prostitutes are described with regard to syphilis infection. For those women who permitted serological tests (n = 1095), 30.59% (confidence interval (CI): 30.55%-30.63%) were positive for markers indicating current or prior infection. After adjustment was made for other variables, a significant association with syphilis infection was observed for periods of exposure (i.e. age and years working as a prostitute). No significant associations were detected for either intravenous drug use, or educational attainment. The results of this study are similar to those of some other investigations into the prevalence of syphilis amongst prostitutes. PMID- 9363542 TI - Improvement in AIDS knowledge, perceptions and risk behaviours over a short period in a rural community of Senegal. AB - The objective of this paper is to assess knowledge, perceptions and behavioural changes in response to AIDS in a rural community in the south of Senegal, comparing 2 cross-sectional surveys using standardized questionnaires and performed in 1990-1992 and 1994. An AIDS-related knowledge score was built using 4 questions about routes of HIV transmission, ranging from 0 to 4. The score increased between the 2 surveys from 1.6 to 2.1 for men (P = 0.006) and from 0.8 to 2.6 for women (P < 10(-4)). The proportion of those who responded 'I don't know' to the 4 questions dealing with routes of AIDS transmission decreased from 24% to 14% on the average for men and from 66% to 20% on the average for women. The proportion of men who declared casual sex partners in the past 12 months decreased from 39% to 21% (P = 0.01). However, the proportion remained stable for women (from 15% to 18%). These results show that despite a relatively low level of HIV infection (0.8% of all adults), AIDS-related knowledge increased and at risk behaviour decreased in a rural area of west Africa. PMID- 9363543 TI - Awareness of sexually transmitted disease among women and service providers in rural Bangladesh. AB - Sexually transmitted disease (STD) in rural Bangladesh is currently a topic of great concern. To date, little information is available in the literature regarding its prevalence. It is now known, however, that the current level of STD awareness among the rural population with regard to modes of transmission and means of prevention is inadequate. In 1994, the MCH-FP Extension Project (Rural) of ICDDR, B surveyed 8674 married women of reproductive age (MWRA) in 4 rural thanas to examine their awareness of STDs. The association between socio demographic and programmatic factors (variables which affect STD information availability) and awareness of STDs was examined by both bivariate and multivariate analyses. Seven focus group discussions were conducted among groups of government health and family planning workers and paramedics to assess their knowledge of STDs and attitudes about their prevention. Only 12% of the original group had even a basic understanding about STDs and how to protect themselves from them. Twenty-five per cent of the women surveyed had ever heard of either syphilis or gonorrhoea. Of these women, less than half could mention specific mechanisms involved in the transmission of these diseases. Seven per cent reported that syphilis and gonorrhoea are transmitted through sexual intercourse. Thirteen per cent reported that the infections are transmitted from spouses to their partners. Four per cent reported that STDs can be spread by having multiple sexual partners. The results of logistic regression analysis indicate that awareness of STDs was higher among relatively older women than among younger women. Awareness of STDs was most strongly and positively associated with the education of both the women and their husbands. Awareness of STDs was also found to be higher among women who were more socially mobile (e.g. those who frequent cinemas or mothers' clubs). The findings of focus group discussions indicate that family planning and health care service providers have a moderate level of STD awareness. Modes of transmission and means of prevention, however, were areas of weakness. It will, therefore, be necessary, whether to prevent a potential STD epidemic or to combat current STD prevalence, to implement culturally acceptable and affordable means of disseminating knowledge in rural areas of Bangladesh. Training of health care providers will be an essential first step. PMID- 9363544 TI - Infection by hepatitis B and C virus in female and transsexual Greek prostitutes with serological evidence of active syphilis. AB - Two hundred and thirty female and 43 male-to-female transsexual Greek prostitutes were screened for serological evidence of active syphilis as judged by positivity in both rapid plasma reagin (RPR) test and treponemal (FTA-ABS and TPHA) tests. The rate of active syphilis was 20.9% in the male-to-female transsexual prostitutes and 4.3% in the female ones (P < 0.001, odds ratio = 5.82). In the former group 65.1% had evidence of hepatitis B virus (HBV) infection, and 4.7% of hepatitis C virus (HCV) infection while the respective rates among the latter group were 50.4% and 3.9%. There was no correlation of viral hepatitis marker prevalence with positive syphilis serology. PMID- 9363545 TI - Indirect calorimetry, body composition and small bowel function in asymptomatic HIV-seropositive women. AB - Extrapolation of data from energy balance studies in HIV-seropositive men to HIV seropositive women may be inaccurate due to gender differences in body composition, hormones and metabolism. If women have a different metabolic response to the human immunodeficiency virus (HIV), nutritional advice may differ from HIV-seropositive men. Ten asymptomatic HIV-seropositive women were matched with 10 heterosexual female controls from low-risk groups. Subjects and controls had assessment of energy and protein intake, resting energy expenditure (REE) and substrate oxidation, small bowel absorption and permeability and body composition. There were no significant differences in REE, substrate oxidation and body composition. Energy and protein intake and small bowel permeability were increased and sugar absorption decreased in HIV-seropositive women (all P < 0.05). Unlike asymptomatic HIV-seropositive men, asymptomatic HIV-seropositive women do not have significant alterations in metabolism or body composition. Therefore, nutritional advice may need to vary according to the gender of the asymptomatic HIV-seropositive subject. PMID- 9363546 TI - Prolonged survival with HIV-1 related nasal non-Hodgkin's lymphoma. PMID- 9363547 TI - Anaphylactoid reaction to ciprofloxacin. PMID- 9363548 TI - Is there a role for positron emission tomography scanning in HIV-positive patients with Kaposi's sarcoma and lymphadenopathy: two case reports. PMID- 9363549 TI - Acceptability of genitourinary medicine services in Middlesbrough, England. PMID- 9363550 TI - Moritz Kaposi (1837-1902). AB - Today, Kaposi is remembered for giving the first description of the angiosarcoma which bears his name. During his lifetime, he was acknowledged as one of the great masters of the Vienna School of Dermatology, a superb clinician and renowned teacher. PMID- 9363551 TI - Attitudes towards HIV testing of patients attending hospital. PMID- 9363552 TI - Heterosexual gonorrhoea and sexual behaviour. PMID- 9363553 TI - Histopathologic comparison of conventional radial keratotomy and minimally invasive radial keratotomy in rabbits. AB - The aim of the present study was to compare conventional radial keratotomy (RK) with minimally invasive RK (mini-RK) in terms of achieved incisional depth as well as the histopathologic changes in the rabbit corneal structures. Four conventional RK incisions were performed on the right eye and four mini-RK incisions were performed on the left eye of 12 Island rabbits using a centripetal cutting technique. The corneas were excised 20 days after the procedure and examined by light microscopy. Histopathologic examination showed that the mean achieved incisional depth (73.47%) in conventional RK was consistent with the intended incisional depth (80%). However, the mean achieved incisional depth (47.28%) was far from the intended incisional depth (80%) in eyes receiving mini RK. The difference between achieved incisional depth of the two surgical techniques was statistically significant (t = 10.70, P < 0.05). Corneal structural changes and epithelial plug formations were less in eyes in mini-RK than in conventional RK. These findings suggested that the refractive results in mini-RK may be less effective than conventional RK. On the other hand, in the mini-RK group, less epithelial plug formation and limited histopathologic structural alterations may have an important role in preventing long-term overcorrection and corneal rupture after ocular trauma demonstrated in conventional RK technique. PMID- 9363554 TI - Pentosidine and autofluorescence in lenses of diabetic patients. AB - Pentosidine, an advanced glycation endproduct, may cause the increased fluorescence found in the lenses of diabetic patients. We measured the autofluorescence in human lenses, in vitro, and quantified the pentosidine to examine its relationship to the autofluorescence. Lens autofluorescence was higher in diabetic than non-diabetic subjects; pentosidine quantities were significantly higher in the diabetic than the non-diabetic group indicating that pentosidine was involved in the greater intensity of autofluorescence in the lenses of patients with diabetes mellitus. PMID- 9363555 TI - Histological study of intraocular changes in rabbits after intravitreal gas injection. AB - To study the effects of different intravitreal gases on intraocular tissues, adult pigmented rabbits were given 0.4 mL intravitreal injections of air, 50% sulfur hexafluoride (SF6) and air, 100% SF6, 50% perfluoropropane (C3F8), or 100% C3F8. On postinjection days 1, 4, 7, and 14, the eyes were removed and the iris, ciliary body and retina processed for light and electron microscopy. Histopathological examination found no abnormalities in eyes that received air and none in the irises of gas-injected eyes. Eyes that received 50% or 100% SF6, or 50% C3F8 had vacuolar changes in the ciliary body and retina after maximum gas expansion; these changes were transient, returning to normal as the gas was absorbed. Eyes that received 100% C3F8 suffered irreversible damage to the ciliary body and retina, in both the superior and inferior portions. These observations indicate that expansion of some intravitreal gases can cause both reversible and irreversible changes in intraocular tissues. The degree of damage is affected by the duration of exposure and the gas concentration. Highly concentrated, long-lasting gases can cause irreversible changes resulting in breakdown of the blood-ocular barrier and impaired retinal function. PMID- 9363556 TI - Comparison of indocyanine green and fluorescein angiography of choroidal neovascularization. AB - We compared indocyanine green (ICG) and fluorescein angiography for evaluation of choroidal neovascularization (CNV). Cast preparations of CNV induced in monkey eyes by laser photocoagulation were correlated with ICG and fluorescein angiographies of the same CNV formations. Fluorescein angiography was more effective, in general, than ICG angiography in detecting CNV; however, CNVs with subretinal hemorrhage (2 of 35 sites) were visible only with ICG angiography. In early phase ICG angiography, CNV formations that casts showed to be dense or composed of thick vessels were seen, but less dense areas were not visible. Lesions that ICG angiography revealed as leaking were not differentiated morphologically from non-leaking areas by the CNV casts. This study confirms that only ICG angiography can identify CNV hidden by subretinal hemorrhage, although fluorescein angiography is otherwise superior. Indocyanine green angiography is indicated as a valuable complement to fluorescein angiography for evaluation of CNV. PMID- 9363557 TI - Effect of topical timolol on tissue circulation in optic nerve head. AB - The effects of topical 0.5% timolol on tissue circulation in the albino rabbit optic nerve head (ONH) were investigated using a laser speckle tissue circulation analyzer. In the first experiment, the normalized blur (NB) value, a quantitative index of tissue blood flow velocity in the ONH, intraocular pressure (IOP), blood pressure, and pulse rate were measured under general anesthesia before, and 30, 60, 90, and 120 minutes after a 20 microL instillation of timolol in one eye and the vehicle in the other eye in a masked, randomized manner. In the second experiment, one eye of a rabbit received timolol twice daily for 20 days and the fellow eye received the vehicle in a masked, randomized manner. Every 5 days IOP was measured and the NB in the ONH and IOP were measured before treatment and 2 hours after the last instillation on the 20th day. After a single instillation of timolol, PR showed a maximum reduction of 12% and IOP in the timolol-treated eyes showed a maximum decrease in 25%. NB in the ONH and BP did not show any significant change during the experiment. After a 20-day treatment with timolol, IOP showed a maximum decrease of 25% in the timolol-treated eyes and 16% in the vehicle-treated eyes. The NB in the timolol-treated eyes increased significantly by 16% (P < 0.01), whereas that in the vehicle-treated eyes showed no significant change. It was suggested that long-term topical timolol with a normal drug regimen caused a significant increase in the peripheral blood velocity in the ONH only in the timolol-treated eyes, at least partly, by local penetration of the drug. Ocular penetration of topically applied timolol is thought to be similar between rabbit and human eyes. Therefore, the present results may have clinical implications. PMID- 9363558 TI - Impression cytology, tear film break up, and Schirmer test in patients with inactive trachoma. AB - Schirmer I and tear film break up time (BUT) test were used to determine cytological changes and conjunctival surface epithelial morphology was investigated using impression cytology in patients with inactive trachoma; patients with mild and severe scarring, and control subjects, were compared. Schirmer I, BUT, and goblet cell populations were significantly lower whereas the grade of squamous metaplasia was significantly higher in patients with inactive trachoma. There was a close correlation between our findings and the clinical severity of trachoma. PMID- 9363559 TI - Genome analysis of adenovirus type 4 strains isolated from acute conjunctivitis in Japan. AB - Strains of adenovirus type 4 (Ad4) isolated from patients with acute conjunctivitis were studied by DNA restriction analysis. The strains were isolated between July and December 1990 in Japan. All 63 isolates of Ad4 were identified as the genome type Ad4a. This study showed that the same Ad4 genome type, Ad4a, caused acute viral conjunctivitis, even in different areas of Japan. PMID- 9363560 TI - Augmented expression of CD44 splice variants in lymphoproliferative disorder of the lacrimal gland in Sjogren's syndrome. AB - We explored the involvement of CD44 isoforms in lymphoproliferative disorder (LPD) of the lacrimal gland of a Sjogren's syndrome patient with unilateral LPD. The CD44 variant with the v6 exon was selectively detected from infiltrating lymphocytes in the gland with LPD, but not from infiltrating lymphocytes in the normal lacrimal gland, suggesting that the CD44 v6 variant exon may be closely associated with the development of LPD in Sjogren's syndrome. PMID- 9363561 TI - Long-term prognosis of extracapsular cataract extraction and intraocular lens implantation in diabetic patients. AB - Although cataract extraction with intraocular lens implantation (IOL) is being used for increasing numbers of patients, there is still insufficient information regarding the long-term outcome for these patients. In this retrospective study of 140 eyes of 102 patients, 97 eyes (69%) achieved a best visual acuity of 20/40 or better. After a minimum 6-month postoperative period, 26 eyes (19%) had developed retinopathy: eight eyes progressed from nonproliferative to proliferative retinopathy. Glycosylated hemoglobin levels and fasting blood glucose were significantly higher at time of surgery in the eight that progressed than in those who did not (P = 0.002, P = 0.034). There were 65 unilateral IOL implantations; in 10 (15%) of these eyes, retinopathy progressed. Retinopathy also progressed in 70% of the fellow eyes of these patients. In patients whose retinopathy did not progress, 95% of the fellow eyes also showed no progression. Also, patients with progression in the pseudophakic eye frequently had progression in the fellow unoperated eye. Postoperative progression was symmetrical (P = 0.0001). Our analysis suggests that progression of diabetic retinopathy following IOL implantation can be correlated to diabetic control at the time of surgery. PMID- 9363562 TI - Abnormal vitreous structure in optic nerve pit. AB - A 37-year-old man presented with an optic nerve pit and serous macular detachment of the left eye. Scanning laser ophthalmoscopy revealed a cyst-like structure terminating at the pit in the premacular vitreous. During ocular movement, this structure moved vigorously and seemed to exert traction on the pit. We believe that it is part of an anomalous Cloquet's canal, and that traction on the pit may be a significant factor in the development of serous macular detachment in this patient. PMID- 9363563 TI - Vascular optic neuropathy in diabetes mellitus. AB - A retrospective analysis of clinical profiles of 20 patients with anterior and posterior ischemic optic neuropathy and diabetic papillopathy was used to evaluate optic neuropathy in diabetes. We found that vascular optic neuropathy in diabetic patients resulted from microangiopathy, macroangiopathy, and certain structural factors in the optic nerve head. PMID- 9363564 TI - Treatment of full-thickness macular holes with autologous serum. AB - A total of 28 patients (29 eyes) with stage 2-4 idiopathic full-thickness macular holes were treated with the use of autologous serum. Autologous serum (20-30 microL) was placed over each macular hole followed by injection of 16% perfluoropropane gas. Postoperatively, 28 eyes (97%) had flattening of the macular hole, and the hole could not be detected in 27 eyes (93%). Twenty-two eyes (76%) showed visual acuity improvement by at least two lines or more. Preoperative factors such as good visual acuity, earlier stage, and younger age were correlated with postoperative good visual acuity. These results suggest that autologous serum is beneficial in the treatment of full-thickness macular holes. PMID- 9363565 TI - Extracts of rhinoceros horn are not antipyretic in rabbits. AB - We administered extracts of the horn of the African Black rhinoceros intragastrically to 7 rabbits, at the same time as injecting bacterial lipopolysaccharide (LPS) intravenously into the rabbits to produce fever. At a dose of horn (50 mg/kg) similar to that allegedly used to reduce human fever, and at ten times that dose, the fever response to LPS was not significantly different (P > 0.05, t-test) to the response to LPS injection when boiled water was administered instead of horn extract. The known antipyretic indomethacin, however, at a dose of 10 mg/kg significantly reduced the response to LPS. PMID- 9363566 TI - Segmental difference of water and electrolyte transport in rat colon in vivo. AB - The segmental difference of water and electrolyte transport in the rat colon was studied in vivo. The proximal and distal colon segments were perfused separately but simultaneously at a constant rate with physiological solution, and net movements of water, sodium and chloride were determined. The effects of osmolality and sodium concentration of perfusate were assessed. The effect of a sodium channel blocker on the net transport of water and electrolytes was also studied in each colon segment. The net absorption of water, sodium and chloride correlated with the sodium concentration and osmolality of the perfusion solution in both colon segments and were dominant in the distal colon segment in each condition, compared with that in the proximal colon segment. The concentrations of three electrolytes in the collected fluid were almost the same as those of the perfusion solutions in both segments and these results indicated that water was transported isotonically through the colon lumen. Benzamil, a specific sodium ion channel blocker, inhibited net water and sodium absorption by 58.8% and 63.1% in the proximal colon segment and by 52.0% and 43.6% in the distal colon segment, respectively. These results suggest the existence of an electrogenic sodium transport mechanism and a paracellular pathway in normal (i.e., not treated with corticosteroids or sodium-depleted food) rats which has not been detected in in vitro studies with both apical and basolateral membrane vesicles. PMID- 9363567 TI - Protective effect of antioxidant vitamins on red blood cell lipoperoxidation induced by SO2 inhalation. AB - The aim of this research was to determine whether administration of antioxidant vitamins can reduce oxidant damage in erythrocytes induced by sulfur dioxide (SO2) inhalation. Meth- and sulfhemoglobin ratios, malonyldialdehyde (MDA) levels, osmotic fragility ratios and hematological parameters of a total of 28 rats were compared. SO2 was given at 10 ppm, 1 hour daily, for 45 days in a specially designed chamber. DL-alpha-Tocopherol acetate (40 mg/kg) and Na ascorbate (200 mg/kg) treatments, initiated 3 days before SO2 exposures, were applied intraperitoneally 3 times a week for 45 days. Meth- and sulfhemoglobin ratios, MDA levels and osmotic fragility ratios were significantly higher in the SO2-treated group (p < 0.05). Significant decreases in MDA levels and osmotic fragility ratios were observed in the antioxidant-treated group (p < 0.05). SO2 inhalation resulted in higher MDA levels and osmotic fragility ratios, which can be reduced by vitamin E + C combination. PMID- 9363568 TI - A chemiluminescence assay detecting the antioxidative effects of glutathione and uric acid on erythrocytes and hemolysates exposed to t-butyl hydroperoxide. AB - The aim of this study was to compare the antioxidative effects of glutathione (GSH) and uric acid (UA) on erythrocytes and hemolysates exposed to t-butyl hydroperoxide, by using a chemiluminescence (CL) technique. CL formation was induced by t-butyl hydroperoxide in an experimental system consisting of erythrocytes and hemolysates in Tris-HCl buffer (pH 7.4). GSH or UA was added as an antioxidant. In erythrocytes, 10 microM and 50 microM concentrations of either GSH or UA reduced the maximum chemiluminescence values (MCVs) significantly when compared to those of controls. In erythrocytes, MCVs observed in the 50 microM GSH group were significantly lower than those of the 50 microM UA group. In hemolysates, while 10 microM concentration of GSH or UA did not alter MCVs, 50 microM concentration of either GSH or UA reduced MCVs. The reduction of MCVs observed in the 50 microM GSH group was greater than that of the 50 microM UA group. When the effects of equimolar concentrations of GSH or UA on erythrocytes and hemolysates were compared, the MCVs of hemolysates were lower than those of erythrocytes. These results can be attributed to the fact that antioxidant agents react much more easily in the hemolysate medium. PMID- 9363569 TI - Microscopic analysis of pressure ejection of drugs from micropipettes. AB - Ejection of drugs from micropipettes by pressure is widely used for chemical stimulation of cells in electrophysiological experiments, but little is known about the dynamics of the processes involved. Several aspects of the formation of liquid droplets were studied by photographing them under a microscope using brief light flashes. The observations led to the following conclusions: 1. The characteristics of the micropipette tip strongly influence both the amount of liquid and the shape of the droplet. Micropipettes were divided according to their tip diameter. Those with a 3-8 microns diameter tip produce small droplets that remain near the tip; those with a tip diameter of 9-15 microns produce conical droplets that extent some distance from the tip; droplets ejected from micropipettes with tip diameter greater than 15 microns are mushroom-shaped and reach distances several hundred microns from the tip. 2. Back-flow of the bath medium, due to capillary force, diminishes the amount of the drug ejected from the micropipette. This effect is very prominent when brief (< 100 ms) pressure pulses are used, and to overcome it priming of the micropipettes several seconds before use is required. 3. Flow of the bath medium can divert the droplet from the expected trajectory. This point was verified during intracellular recordings of responses to pressure-ejected substance P in myenteric neurons. The recommended parameters for optimal use of pressure ejection are: tip diameter of 10-15 microns, pressure of 80-100 kPa, pulse pressure duration over 100 ms and priming by pressure pulse of 1-2 s duration; liquid column of about 5 cm can minimize back-flow. PMID- 9363570 TI - Quantification of ofloxacin in biological fluids by high-performance liquid chromatography. AB - A simple HPLC assay was evaluated for analysis of ofloxacin in biological fluids. Mobile phase contained methanol (40%) and phosphate buffer (pH 3.5, 60 mmol/l) and a common C18 column was used. Detection was set at 280 nm (UV). Biological fluids (50 microliters) were prepared for assay by protein precipitation with acetonitrile (1/1, vol/vol). The assay is linear from 2000 to 10 ng/ml and sensitive to 10 ng/ml. The mean recovery of ofloxacin from serum was 99.4%. The coefficient of variation was < or = 4.0% for same-day precision and < or = 6.8% for assay-to-assay precision. Because the assay requires only small specimens volumes and minimal sample preparation, this assay provides a simple to use, sensitive and specific method for quantification of ofloxacin in biological fluids. PMID- 9363571 TI - Induction of calcium-dependent action potentials by 4-aminopyridine in potassium depolarized guinea-pig papillary muscle. AB - Exposure of guinea-pig papillary muscle to 22 mM K+ resulted in loss of electromechanical excitability accompanied by an elevation of mean electrical threshold by 8.96 V and a membrane depolarization of about 47.3 mV. After setting the threshold to a new sensitive level for stimulation, 4-AP (1.25-5 x 10(-3) M) could restore both the propagated action potentials typical for Ca2+ (e.g. resting potential: -46 mV; action potential amplitude: 74.25 mV; upstroke velocity: 11.4 V/sec; abolition by Ca(2+)-channel blokers) and contractions to papillary muscle cells, with further elevation of resting potential from -51.2 mV to -46 mV. Restoration of electromechanical activity by 4-AP was dose-dependent and susceptible to blockade with D600 (5 x 10(-7) M). From these data, it was concluded that 4-AP restored electrical and mechanical excitability by increasing membrane conductance to Ca2+ (gCa2+). PMID- 9363572 TI - Effect of hypothermia on the survival of the immature pig in a confined atmosphere. AB - The rat has an optimal body temperature (TB = 20 degrees C) for hypoxic survival in a confined space. The general applicability of this finding and the influence of body size was studied in immature pigs (27 kg). The pig consumed oxygen in a sealed chamber until it reached the terminal state. We measured blood pressure, inspired O2 and CO2, minute ventilation, ECG, ambient and body temperatures, and PO2, PCO2, O2-content and pH in arterial and venous blood. Four different cooling procedures produced a terminal TB of 26 +/- 3.1 degrees C, 30.1 +/- 2.9 degrees C, 30.0 +/- 2.8 degrees C and 22.6 +/- 2.1 degrees C and a terminal PIO2 of 28.0 +/- 10.2 torr, 30.8 +/- 7.6 torr, 31.5 +/- 5.6 torr and 41.7 +/- 15.4 torr respectively (mean +/- SD). Oxygen consumption, minute ventilation and cardiac output increased from baseline values of 0.5 l.h-1.kg-1, 10 l.min-1, and 6 l.min 1 respectively at the start of cold exposure, and declined moderately as a function of PIO2 below 60 torr. With respect to the relation between terminal body temperature and terminal PIO2 (but not PaO2), we found an optimal body temperature (26 degrees C) at which the animal can survive to the lowest PIO2. Using the allometric approach, i.e. linear extrapolation of temperature as a function of logarithm body mass, the optimal body temperature for man would be 27.5 degrees C. The advantage of hypothermia in the hypoxic survival of the whole animal is its effect on the reduction of the inspired-arterial O2 difference. PMID- 9363573 TI - Annotation: correspondence analysis. AB - Correspondence analysis is a useful technique in the investigation of relationships between categorical variables. By displaying these relationships graphically, correspondence analysis solutions may allow investigators to obtain insights into the structure of their data more readily than would be obtained by simply studying tables of numerical values and examining associated chi-squared statistics. Some experience of using correspondence analysis solutions in practice is generally necessary to appreciate the method's usefulness fully. An interesting application of the method in a longitudinal study of cognitive development is given in Lautrey and Cibois (1992), and some suggestions as to how best to combine correspondence analysis with a more formal method such as log linear modelling are given in Van der Heyden and de Leeuw (1985). PMID- 9363574 TI - Annotation: on the grandmothers' role in the adjustment and maladjustment of grandchildren. AB - The present annotation explores the impact of grandmother involvement on their grandchildren's adjustment. A review of relevant research suggests that the impact of such involvement is conditional on a range of factors, including (a) the level of need experienced by the mother and child, (b) the mother-grandmother relationship history, (c) the developmental stage and life circumstances of the grandmother, (d) the levels of disagreement between mother and grandmother over child-related issues, and (e) the perceived appropriateness of involvement in cultural and interpersonal terms. Under most circumstances grandmother involvement is not a pre-requisite for grandchild adjustment. Where a genuine need for support exists and the support offered is tailored to meet that need, then grandmother involvement can represent a protective feature of the family environment. However, in situations where no such need exists, or the grandmother mother relationship history precludes a harmonious relationship, then grandmother involvement can represent a risk factor and have a negative effect on family functioning and child adjustment. PMID- 9363575 TI - Practitioner review: the pharmacotherapy of adolescent depression. AB - This paper is a review of the pharmacotherapy of adolescent depression. It begins with a brief discussion regarding the nature of adolescent depression and then critically evaluates the available evidence regarding the efficacy and tolerability of psychotropic intervention as it has, to date, been reported. As the available evidence suggests that tricyclic antidepressants have failed to show efficacy, yet demonstrate significant problems with tolerability and safety, the remainder of the article describes how clinicians should prescribe antidepressants using the serotonin reuptake inhibitors. Areas covered include assessment, treatment initiation, dosing, outcome evaluation, adverse events, and combinations. The review concludes with a discussion of long-term therapy with antidepressant medications. PMID- 9363576 TI - Behavioural development in children of divorce and remarriage. AB - We employed an autoregressive modelling technique with data from the Quebec Longitudinal Study to prospectively examine the developmental impact of family transition on behaviour while controlling for predivorce and preremarriage effects. Teachers rated children's anxious, hyperactive, physically aggressive, oppositional, and prosocial behaviour every 2 years from kindergarten through to the end of elementary school. Once individual and parental characteristics and antecedent family events were controlled, children who experienced parental divorce before age 6 exhibited comparatively more behavioural disturbance than their peers whose parents divorced later. With the exception of a protective effect on hyperactive behaviour, remarriage did not have a significant impact on children's behaviour when the legacy of divorce was controlled. Although the results suggest that children of divorced parents show difficulty in many areas of functioning, the effects of family transition on behavioural development were dependent on the child's age and the specific behavioural dimension assessed. Compared to other points in development, early childhood divorce was associated with long-term increases in anxious, hyperactive, and oppositional behaviour during later childhood. The effects of divorce on children's fighting were short lived. Unlike previous prospective studies that suggest predivorce effects, we did not observe behavioural disturbance prior to divorce or remarriage. PMID- 9363577 TI - Children raised in fatherless families from infancy: family relationships and the socioemotional development of children of lesbian and single heterosexual mothers. AB - The aim of the study was to investigate family functioning and the psychological development of children raised in fatherless families from their first year of life. Thirty lesbian mother families and 42 families headed by a single heterosexual mother were compared with 41 two-parent heterosexual families using standardised interview and questionnaire measures of the quality of parenting and the socioemotional development of the child. The results show that children raised in fatherless families from infancy experienced greater warmth and interaction with their mother, and were more securely attached to her, although they perceived themselves to be less cognitively and physically competent than their peers from father-present families. No differences were identified between families headed by lesbian and single heterosexual mothers, except for greater mother-child interaction in lesbian mother families. PMID- 9363578 TI - Communication between parents and deaf children: implications for social emotional development. AB - Parent-child communication plays a central role in social growth, as it does in other domains of development. Over 90% of deaf children, however, have hearing parents who frequently do not have a fully effective means of communicating with them. This paper examines the role of effective parent-child communication in the social and emotional development of deaf children. Evidence concerning relations between early communication and social-emotional development of deaf children is reviewed, and superficial differences in the ways that parents interact with deaf versus hearing children are distinguished from differences that may have more significant and enduring effects. Hearing parents and their deaf children are found to develop alternative, often nonverbal, interaction strategies. Of primary interest is the extent to which those strategies have impact comparable to the strategies of hearing parents with hearing children or deaf parents with deaf children. PMID- 9363579 TI - Temperament in late talkers. AB - This study examines the temperamental characteristics of children who were identified at age two as being slow in expressive language development, and those of peers with normal language history. When the children were in first grade (approximately age six), parents and clinicians rated subjects' temperamental characteristics, using a standardized temperament assessment instrument. Subjects with a history of slow expressive language development were rated significantly lower on Approach/Withdrawal--indicating shyness, aloofness, or reduced outgoingness--than peers with normal language history. Approach/Withdrawal scores were significantly correlated with average sentence length in spontaneous speech, and this measure also predicted Approach/Withdrawal scores in regression analyses. The clinical and theoretical implications of these findings for early language delay are discussed. PMID- 9363580 TI - Another advanced test of theory of mind: evidence from very high functioning adults with autism or asperger syndrome. AB - Previous studies have found a subgroup of people with autism or Asperger Syndrome who pass second-order tests of theory of mind. However, such tests have a ceiling in developmental terms corresponding to a mental age of about 6 years. It is therefore impossible to say if such individuals are intact or impaired in their theory of mind skills. We report the performance of very high functioning adults with autism or Asperger Syndrome on an adult test of theory of mind ability. The task involved inferring the mental state of a person just from the information in photographs of a person's eyes. Relative to age-matched normal controls and a clinical control group (adults with Tourette Syndrome), the group with autism and Asperger Syndrome were significantly impaired on this task. The autism and Asperger Syndrome sample was also impaired on Happe's strange stories tasks. In contrast, they were unimpaired on two control tasks: recognising gender from the eye region of the face, and recognising basic emotions from the whole face. This provides evidence for subtle mindreading deficits in very high functioning individuals on the autistic continuum. PMID- 9363581 TI - The impact of childhood non-malignant life-threatening illness on parents: gender differences and predictors of parental adjustment. AB - Mental health, family functioning, effects on employment and relationships, coping style, and perceptions of prognosis were assessed in 93 mothers and 78 fathers of children with a life-threatening non-malignant condition. Results indicated high levels of psychological distress, significant effects upon employment and relationships, and a family environment characterised by low expressiveness, cohesion, and high conflict. Differences between mothers and fathers were found on a number of variables. Length of time since diagnosis, level of family cohesion, and sex of parent significantly predicted parental mental health. PMID- 9363582 TI - Sleep problems in children of affectively ill mothers. AB - The objective of the study was to determine whether the frequency and severity of sleep problems were greater in children of affectively ill mothers than in children of control mothers. Sleep problems were studied in children of mothers with a diagnosis of unipolar (N = 38) and bipolar (N = 23) affective illness and children of mothers with no current or past psychiatric diagnosis (N = 24). Mothers' reports on the Child Behavior Checklist (CBCL) were obtained three times, 4 years apart, on sibling pairs (ages 1.5-3.5 and 5-8 years, respectively, at first assessment). In addition, on the third assessment, the Diagnostic Interview for Children and Adolescents was filled out by mothers and children. In both siblings, sleep problems, as assessed through the CBCL, were more frequent and severe in children of affectively ill mothers. In younger siblings, the persistence of sleep problems was more frequent in children of affectively ill mothers. Co-occurrence of sleep problems among siblings was more frequent in children of affectively ill mothers than in those of control mothers. PMID- 9363583 TI - Developmental outcome of infants born with biological and psychosocial risks. AB - The significance of prenatal and perinatal complications (biological risk) and of family adversity (psychosocial risk) on early child development was examined in a prospective study. Developmental outcome of 350 infants was assessed by measures of motor, cognitive, and social-emotional functioning at 3, 24, and 54 months. Results indicated a differential impact of risk factors on specific outcomes. Whereas psychosocial risks became more prominent with growing age and were related to poorer child outcome in all areas of functioning, biological risks decreased in influence and predominantly resulted in poorer motor development. The contributions of biological and psychosocial risks on outcomes were additive. A number of individual risk factors emerged as significant predictors of later maladaptation. PMID- 9363584 TI - Emotional and semantic priming as a measure of information processing in young people with school refusal: a research note. AB - We investigated semantic and emotional priming of lexical decision-making in 20 school refusers and 20 attenders aged 11-16 years, matched for sex and reading ability. We hypothesised that: semantic and emotional priming would be demonstrable in both samples; and that the school refusers would show emotional priming of school-related words to aversive primes. Both samples showed semantic priming; emotional priming was shown by the attenders and 11 school refusers without a history of depression. School-refusing children did not show emotional priming for school-related words. Nine school-refusing children with either current or past depression showed a general reduction in their priming. These results show that both semantic and emotional priming can be detected in this age range. They do not support school refusal being typically associated with anxiety about school. The reduction in priming in those with a depressive history is similar to inhibition in information processing in depressed adults. Priming is therefore sensitive to at least some psychiatrically relevant states or traits in this age-range. It is concluded that priming could be a useful measure of information processing in this age-group, and further research is warranted. PMID- 9363585 TI - Depressive symptoms in children and adolescents: etiological links between normality and abnormality: a research note. AB - This research note considers whether normal and abnormal depressive symptoms are caused by the same or differing etiologies. The comparison of the heritability of individual differences with extreme group heritability, along with the use of multiple cut-offs to define abnormal groups, can be used to answer this question and to bridge the gap between dimensional and categorical approaches to developmental psychopathology. Depressive symptoms from 395 same-sex child twin pairs were analysed in this way. Genetic factors contributed to a similar extent both to individual differences (h2 = .48) and to extreme group membership using multiple cut-offs (hg2 = 2.0-2.3). The common environment did not contribute significantly in any of the analyses but showed a trend for a greater role in extreme group membership. These results are in good agreement with previous data. PMID- 9363586 TI - Parental divorce and adult psychological distress: evidence from a national birth cohort: a research note. AB - An association was found between childhood parental divorce and adult psychological distress in a British national birth cohort at ages 23 and 33. No moderating effects were found for gender, age at separation, or remarriage of the custodial parent. Participants who were young adults when their parents divorced also showed increased levels of symptomatology, whereas those who experienced parental death in childhood showed no increased risk. An interaction between parental divorce and own divorce in women, giving particularly high symptom levels, arose from a selection process in those from divorced families of origin only, with high 23-year scores predicting subsequent divorce. Own divorce was associated with an increase in distress between age 23 and 33, but this was irrespective of family of origin. PMID- 9363587 TI - Characterization of human platelet IgG Fc receptor associated with membrane glycoprotein. AB - Human platelets express IgG Fc receptors (Fc gamma R). Previously we reported that circulating immune complexes (CIC) inhibited fibrinogen binding to platelet glycoprotein IIb/IIIa complex (GPIIb/IIIa) and that isolated Fc gamma R were recognized by monoclonal antibodies (mAb's) to GPIIb and GPIIIa (J.Lab. Clin. Med. 117:209-217, 1991). In this study, we further characterized the properties of the Fc gamma R and the activity associated with GPIIb/IIIa. Binding of Fc portion of human IgG (Fc) to the platelet Fc gamma R associated with GPIIb/IIIa complex, unlike fibrinogen receptor, did not require divalent cations. The Fc gamma R bound to immobilized immune complex were recognized by mAb's to GPIIb, GPIIIa, GPIIb/IIIa. Preincubation of platelet extract with fibrinogen inhibited the binding of heat-aggregated IgG (HAG) to the extract. Flow cytometry of whole platelets revealed inhibition of mAb binding to GPIIb/IIIa, when platelets were incubated with Fc fragments or HAG. Using platelet extract coated to microtiter plates, similar findings were noted with Fc and HAG. The dissociation of GPIIb/IIIa complex by incubating platelet extract at 37 degrees C in the presence of EDTA caused a marked decrease in the binding of GPIIb and GPIIIa to the immobilized immune complex. Activation of intact platelets with ADP resulted in an increased binding of HAG to the platelets, indicating that an augmented Fc gamma R activity is associated with the activation of GPIIb/IIIa. These results suggest a close relationship of the Fc gamma R activity to the fibrinogen binding site (GPIIb/IIIa complex). PMID- 9363588 TI - The effect of Padma-28, a traditional Tibetan herbal preparation, on human neutrophil function. AB - Human neutrophils were studied in vitro in the presence of the herbal preparation Padma-28. At concentrations higher than 0.3 mg/ml, the Padma-28 induced O2- production in unstimulated neutrophils. At lower concentrations, O2- production was inhibited in phorbol myristate acetate (PMA) stimulated cells. Lysozyme release by PMA and opsonized zymosan-stimulated cells was inhibited by Padma-28 at a concentration dependent manner. On the other hand, random and directed migration and adhesion to nylon fibers were not affected. These results suggest that Padma-28 may have anti-inflammatory activity whose mechanism remains to be elucidated. PMID- 9363589 TI - Human platelet Fc receptors: binding kinetics of Fc derivatives to the receptors. AB - Human platelets are known to carry Fc receptors (Fc R), but the binding characteristics between ligands and Fc gamma R has not been well elucidated. In this study, we investigated the binding kinetics of IgG Fc fragments (Fc) to Fc R, the association and dissociation characteristics of the ligands to and from Fc gamma R using enzymatically modified Fc fragment derivatives. Approximately 60 minutes and 90 minutes were needed at 37 degrees C and 22 degrees C, respectively, for complete saturation of the Fc binding sites with horseradish peroxidase-conjugated Fc (HPO-Fc). Heat aggregated IgG (HAG) had a greater affinity for the Fc gamma R than Fc monomers. Additional binding of HAG was observed even after the binding sites were saturated with Fc monomers. This could be explained by different binding sites available only for immune complexes or by the partial dissociation of binding sites saturated with Fc by HAG. Further, we noted partial dissociation of HPO-Fc, when HAG was added after saturation of the binding sites with HPO-Fc. In a subsequent experiment, we compared the relative affinities of chemically or enzymatically modified Fc derivatives for Fc gamma R. HAG, which was used as a model for CIC, had a greater affinity for platelet Fc gamma R than IgG monomer and Fc derivatives. Pepsin-digestion of Fc caused a total loss of its affinity for the Fc gamma R, whereas b-mercaptoethanol-treated Fc fragments demonstrated substantial binding to the Fc gamma R. These results indicate that the pepsin digestion affects the Fc portion and causes a disruption in the area of the Fc which is essential for the recognition by the platelet Fc gamma R. On the other hand, cleavage of disulfide bridges by beta-mercaptoethanol resulted in a marked increase in affinity for the Fc gamma R. On the other hand, enzymatic cleavage of the carbohydrate moieties of Fc did not alter the affinity of Fc fragments for the Fc gamma R, indicating that the carbohydrates play an insignificant role or are not involved in their binding to the Fc gamma R. PMID- 9363591 TI - Hematopoietic growth factors stimulate paraprotein isotype production by bone marrow mononuclear cells in an aggressive case of multiple myeloma. AB - We describe a patient with multiple myeloma (MM), whose bone marrow (BM) cells were capable of spontaneous paraprotein isotype secretion, which could be strongly stimulated by hematopoietic growth factors (GFs), such as interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), G-CSF and IL 3. Ig production by BM cells from another five MM patients and four control patients with non-malignant hematological diseases could not be stimulated by these GFs. The results indicate that GFs, at least in some instances, can activate tumoral plasma cells in patients with MM. This possibility should be taken into account when the utility and effectiveness of GFs in the treatment of MM is evaluated. PMID- 9363590 TI - T cell activation in vivo by dengue virus infection. AB - It is accepted that T cells play a critical role during virus infections; however, T cell responses in vivo in acute stage of virus infection are not understood. We examined T cell activation in vivo in two volunteers who developed dengue fever in response to vaccination with a candidate live dengue vaccine. Serial plasma collected from the volunteers from day 0 (before infection) to day 17 after infection were examined for levels of soluble interleukin-2 receptor (sIL-2R), soluble CD4 (sCD4), soluble CD8 (sCD8), interleukin-2 (IL-2) and interferon gamma (INF gamma). Elevation of the levels of sIL-2R, IFN gamma, sCD4 and IL-2 became obvious during the period of viremia and was followed by a later increase in the level of sCD8. The levels of IFN gamma and sIL-2R declined after the end of the period of viremia. These results indicate that i. T cells are activated in vivo by dengue virus infection ii. activation of CD4+ T cells occurs during the period of viremia iii. activation of CD8+ T cells follows CD4+ T cell activation. These results suggest that activation of T cells in vivo may contribute to controlling acute dengue virus infections. PMID- 9363592 TI - Mapping 28 erythrocyte antigen, plasma protein and enzyme polymorphisms using an efficient genomic scan of the porcine genome. AB - One hundred and fifty-four microsatellite markers were selected for genomic scanning of the porcine genome and were grouped into amplification sets to reduce the cost and labour required. Thirty amplification sets had two markers (duplex), 20 sets had three markers (triplex) and five sets had four markers (quadruplex) while 14 markers were analysed separately. The selection criteria for microsatellites were: ease of scoring, level of polymorphism, genetic location and ability to be genotyped in a multiplexed polymerase chain reaction (PCR). The selected microsatellites were chosen to span the entire genome flanked by the porcine linkage map with intervals between adjacent markers of 15-20 cM where possible. The utility of this set of markers was demonstrated by linkage analyses with loci controlling blood plasma protein and red cell enzyme polymorphisms (n = 13), erythrocyte antigens (n = 15), the S blood group, coat colour and ryanodine receptor from 174 backcross Meishan-White Composite pigs. These loci displayed various forms of inheritance and most (24 loci) have been placed in linkage groups. Significant two-point linkages (lod > 3.0) were detected for each polymorphic marker. These results provide the first linkage assignments for phosphoglucomutase (PGM2) and erythrocyte antigen F (EAF) to SSC8; and serum amylase (AMY) and erythrocyte antigen I (EAI) to SSC18. All of the remaining polymorphic loci (n = 24) mapped to previously identified regions confirming earlier results. Most of the markers used in this study should be useful in resource populations of various breed crosses as the number of alleles detected in a multibreed reference population was one of the selection criteria. PMID- 9363593 TI - Non-association between Rfp-Y major histocompatibility complex-like genes and susceptibility to Marek's disease virus-induced tumours in 6(3) x 7(2) F2 intercross chickens. AB - Marek's disease (MD) is a lymphoproliferative disease caused by a member of the herpesvirus family, and the best understood genetic resistance to MD involves the chicken major histocompatibility complex (MHC) B-complex. Preliminary observations have suggested that MHC-like Rfp-Y genes might also influence the incidence of MD. This study describes the differentiation and definition of unique Rfp-Y genes in inbred lines 6(3) and 7(2), lines that possess identical B complex genes, but that are resistant or susceptible to MD, respectively. To assess if Rfp-Y genes affect susceptibility to MD, 265 6(3) x 7(2) F2 chickens were challenged with the JM strain of MD virus at 1 week of age and were evaluated for MD lesions at up to 10 weeks of age. Genotyping of the F2 chickens for Rfp-Y haplotypes was performed by restriction fragment length polymorphism analysis of genomic DNA using TaqI and a B-FIV probe. Analysis of variance and interval mapping procedures were used to determine association between the Rfp-Y haplotypes and the phenotypic MD values of the F2 chickens. The cosegregation analysis of 265 F2 chickens indicated that there was no association between Rfp-Y haplotypes and MD susceptibility. Furthermore, the fact that the Rfp-Y haplotypes fit the 1:2:1 segregation ratio and the Rfp-Y allele frequencies did not differ significantly from 0.5 in the full population or in selected subpopulations (of either 40 MD-resistant or 39 MD-susceptible chickens) also indicated that Rfp-Y haplotypes do not significantly influence MD susceptibility. We conclude that Rfp Y haplotypes do not play a major role in determining the genetic susceptibility to MD in 6(3) x 7(2) F2 White Leghorn chickens. PMID- 9363594 TI - Analysis of genetic relationships between 10 cattle breeds with 17 microsatellites. AB - To guide genetic conservation programmes with objective criteria, general genetic variability has to be taken into account. This study was conducted to determine the genetic variation between 10 cattle breeds by using 17 microsatellite loci and 13 biochemical markers (11 blood groups, the transferrin and beta-casein loci). Microsatellite loci were amplified in 31-50 unrelated individuals from 10 cattle breeds: Charolais, Limousin, Breton Black Pied, Parthenais, Montbeliard, Vosgien, Maine-Anjou, Normande, Jersey and Holstein. Neighbor-joining trees were calculated from genetic distance estimates. The robustness of tree topology was obtained by bootstrap resampling of loci. A total of 210 alleles of the 17 microsatellites were detected in this study and average heterozygosities ranged from 0.53 in the Jersey breed to 0.66 in the Parthenais breed. In general, low bootstrap values were obtained: with the 17 microsatellites, the highest bootstrap values concerned the Holstein/Maine-Anjou grouping with an occurrence of 74%; with the biochemical markers, this node had an occurrence of 79% and the Charolais/Limousin grouping appeared with an occurrence of 74%; when microsatellites and biochemical polymorphism were analysed together, the occurrence of the Holstein/Maine-Anjou grouping was 90% and that of the Charolais/Limousin grouping was 42%. These results suggest that 30 microsatellites, a number currently considered as sufficient to distinguish closely related breeds is, in fact, probably insufficient. PMID- 9363595 TI - Isolation and mapping of two chicken POU family genes and the identification of a syntenic group with human and mouse. AB - Two partial chicken POU domain genes were isolated by genomic library screening and reverse transcriptase-polymerase chain reaction (RT-PCR). A cDNA clone encoding the POU domain of Brn-3a, which showed near identity to the human Brn-3a sequence (100% amino acid identity), was isolated and mapped to chicken linkage group E48. A Skn-1/Epoc-1/Oct-11 genomic clone was identified and mapped to chicken linkage group E49. This mapping identified a syntenic group in chicken linkage group E49 that was conserved with human chromosome 11q23 and mouse chromosome 9. PMID- 9363596 TI - Mapping of growth hormone releasing hormone receptor to swine chromosome 18. AB - The growth hormone releasing hormone receptor (GHRHR) was mapped in the pig for study as a potential candidate gene in controlling pig quantitative growth and carcass characteristics. Primers were designed from the pig GHRHR sequence to amplify a 1.65-kb intronic fragment between exons 6 and 7. By using a pig-rodent somatic cell hybrid panel, GHRHR was mapped to pig chromosome 18 (SSC18) with 100% concordance, and the regional assignment was SSC18q24 with 89% concordance. The polymerase chain reaction-restriction fragment length polymorphisms (PCR RFLPs) with MseI and TaqI were developed to confirm this assignment with linkage analysis by using the European Pig Gene Mapping Project (PiGMaP) reference families. Pig GHRHR was mapped with strong linkage to SSC18 markers S0062 and S0120 (lod > 8). The GHRHR and IGFBP3 were found to map near to each other on human chromosome 7 (HSA7), and the pig IGFBP3 gene has been mapped to SSC18 by others. Our mapping of pig GHRHR increases the comparative information available on the SSC18 maps and further confirms the synteny conservation between HSA7 and SSC18. PMID- 9363597 TI - Isolation, characterization and chromosomal localization of the porcine ciliary neurotrophic factor (CNTF) gene. AB - In the mouse, ciliary neurotrophic factor (CNTF) maintains embryonic stem cells in an undifferentiated state; yet, the heterologous protein has no similar effects on porcine embryonic stem (ES) cells. Consequently, we cloned and sequenced the porcine CNTF gene and assigned it to chromosome 2. The CNTF gene was found to contain two exons, which encoded a deduced polypeptide of 200 amino acids in length with 83%, 82%, 82% and 81% amino acid similarity when compared to known sequences in the rabbit, rat, human and mouse, respectively. Eight non conservative amino acid changes were identified in the porcine protein when compared with other species. Comparison of the 5' region of the porcine CNTF and other mammalian cytokines indicated the presence of several conserved transcription-factor binding motifs, suggesting their importance for controlling the specific expression of these proteins. In addition, CNTF was localized to porcine chromosomes by fluorescence in situ hybridization (FISH). Chromosome arm length ratios were calculated for 40 early metaphase chromosomes and 32 (80%) indicated that the pig CNTF gene is located on chromosome 2p1.6. This was confirmed by aligning R-banded FISH-labelled chromosomes to the standard porcine ideogram. PMID- 9363598 TI - Aldolase C polymorphism in the laboratory opossum, Monodelphis domestica. AB - A two-allele polymorphism in aldolase C was identified in brain extracts of grey short-tailed opposums, Monodelphis domestica, by electrophoresis in starch or cellulose acetate gels. Pedigree data were consistent with autosomal codominant inheritance. The polymorphism was present in two of the six genetically distinct laboratory populations that have been established for this species. PMID- 9363599 TI - A medium density microsatellite map of BTA10: reassignment of INRA69. AB - We have developed a genetic map of BTA10 based on 8952 informative meioses for 13 microsatellite markers and the erythrocyte antigen Z. With the exception of OarAE64, the support for the order of all loci in the map exceeded a LOD > 3.0. The length of the BTA10 genetic map was 87.0 centimorgans (cM). The 14-marker, sex-average map in Kosambi cM was: CSSM38-8.9-BM1237-5.2-HH8A-2.6- INRA69-10.6 TGLA378-0.8-BM6305-17.2- TGLA102-17.9-INRA96-0.3-CSRM60-9.2- DIK20-3.0-EAZ-6.7 CSSM46-3.7-SRCRSP3-1.0-OarA E64 with an average interval of 6.70 cM. The microsatellite INRA69 was recently assigned to the pseudoautosomal region of the bovine X chromosome by linkage analysis. However, we found that twopoint support for linkage between INRA69 and 15 X-linked bovine microsatellites was LOD < 0.50 in 529 reciprocal backcross and F2 fullsib progeny. We performed twopoint analyses of INRA69 against 275 markers distributed throughout the bovine genome and found significant associations with a LOD > 3.0 only between INRA69 and eight BTA10 microsatellite loci. Consequently, we excluded INRA69 from the genetic map of the X chromosome and reassign this microsatellite to BTA10. PMID- 9363600 TI - Isolation of microsatellites from a bovine YAC clone harbouring the SOD1 gene. AB - A bovine yeast artificial chromosome (YAC) clone containing the superoxide dismutase 1 (SOD1) gene was used as a template for polymerase chain reaction (PCR) amplification using a conserved short interspersed nuclear element (SINE) primer. Two highly polymorphic microsatellites with nine and eight alleles were isolated and mapped by linkage analysis to the centromeric region of BTA1. These microsatellites will be used in the construction of a genetic and physical map of the SOD1 region towards positional cloning of the polled gene. PMID- 9363601 TI - Polymorphic sequence of Korean Native goat lactoferrin exhibiting greater antibacterial activity. AB - Lactoferrin, which exhibits antibacterial activity to protect infants from infectious disease, is a major component of colostrum and milk. Lactoferrin was purified from the colostrum of Korean Native goat, and the cDNA from the mammary gland mRNA of the animal was cloned and sequenced. The nucleotide sequence of the lactoferrin gene of Korean Native goat was found to differ in 15 sites from that of the goat lactoferrin gene reported earlier. This difference in nucleotide sequence resulted in six amino acid substitutions: five in the N-lobe and one in the C-lobe. The antibacterial activity of Korean Native goat lactoferrin was found to be greater than that of Sannen goat lactoferrin. PMID- 9363602 TI - A polymorphic (TTTA)n tandem repeat in an intron of the canine factor IX gene. PMID- 9363603 TI - Nine equine dinucleotide repeats at microsatellite loci UCDEQ136, UCDEQ405, UCDEQ412, UCDEQ425, UCDEQ437, UCDEQ467, UCDEQ487, UCDEQ502 and UCDEQ505. PMID- 9363604 TI - A HinfI PCR-RFLP at the porcine leptin (LEP) gene. PMID- 9363605 TI - The microsatellite marker (BFRO 002) characteristic for different geographically remote brown trout, Salmo trutta L., populations. PMID- 9363606 TI - Polymorphism identification in the ACADM, AT3, IL10, MYOG and TSHB genes of cattle. PMID- 9363607 TI - The gene encoding the peroxisome proliferator-activated receptor (PPARA) maps to chromosome 5 in cattle. PMID- 9363608 TI - Microsatellite (TTCC)n polymorphism in intron 6 of the canine rod photoreceptor cGMP-gated cation channel alpha-subunit gene. PMID- 9363609 TI - A novel polymorphism in the bovine insulin-like growth factor binding protein-3 (IGFBP3) gene. PMID- 9363610 TI - A polymorphic microsatellite in the bovine leptin gene. PMID- 9363611 TI - Three cDNA-derived bovine dinucleotide repeat polymorphisms: CSSME069, CSSME070 and CSSME076. PMID- 9363613 TI - Equine dinucleotide repeat loci LEX049-LEX063. PMID- 9363612 TI - UW54 and UW63, two polymorphic bovine microsatellites on chromosomes 6 and 8q18, respectively. PMID- 9363614 TI - Bovine beta-lactoglobulin I is identified by amplification created restriction site using SmaI. PMID- 9363615 TI - A trinucleotide repeat polymorphism is present in bovine CSN1S1. PMID- 9363616 TI - Microsatellite (CA)n polymorphism in intron 2 of the canine rod photoreceptor cGMP-phosphodiesterase alpha-subunit gene. PMID- 9363617 TI - Caprine microsatellite dinucleotide repeat polymorphisms at the SR-CRSP21, SR CRSP22, SR-CRSP23, SR-CRSP24, SR-CRSP25, SR-CRSP26 and SR-CRSP27 loci. PMID- 9363618 TI - Equine dinucleotide repeat microsatellites at the NVHEQ5, NVHEQ7, NVHEQ11, NVHEQ18 and NVHEQ24 loci. PMID- 9363619 TI - Characterization of the COXP1 gene polymorphisms and estimation of allele frequencies in the Lower Saxony Holstein population. PMID- 9363620 TI - Identification of immune inhibitor from Pseudomonas aeruginosa of inducible cell free antibacterial activity in insects. AB - Insect-pathogenic strains of Pseudomonas aeruginosa produce specific proteinase which selectively degrades the cecropin-based defence system of insects. This was demonstrated by the disappearance of the Galleria cecropin and purified Hyalophora cecropin B peptide PAGE bands, but not the lysozyme band, upon exposure to infected extracts and a similar abrogation of antibacterial activity using an agar diffusion assay. In addition, the proteolytic activity of infected extracts produced by high and low virulence Pseudomonas strains was shown to be correlated with cecropin-inhibitory activity. This indicated that the bacterial proteinase was responsible for the ability of bacteria to establish infections and strain virulence. PMID- 9363621 TI - Up-regulation of reactive astrogliosis in the rat glioma 9L cell line by combined mechanical and chemical injuries. AB - The 9L rat glioma cells grown in culture, when subjected to a mechanical injury (scratch wound) and/or a chemical injury (CdCl2) manifest changes which are characteristic of an astrocyte reaction (astrogliosis) in the central nervous system. Such changes include cell hypertrophy and an increase in immunostaining for the astrocytic marker proteins, glial fibrillary acidic protein and J1-31 antigen. Mitochondria also increase in size and number, and the endoplasmic reticulum expands in area. These mechanical and chemical injuries are coordinated, and act synergistically to induce a considerably more intense astroglial reaction by 9L cells than can be elicited with either injurious agent alone, and this occurs without any interactions with microglia, neurons or oligodendroglia. The phenomenon suggests that more than one transcriptional mechanism is involved in the activation of astrocytes, and that mechanical and CdCl2-induced injuries, respectively, probably affect different receptors and second- and third-messenger pathways. There are a number of questions concerning the molecular biology of reactive astrocytes which can be addressed through the use of the 9L rat glioma cell model. This model offers certain advantages over primary cultures of astrocytes, namely a low basal level of reactivity (because the cells are not subjected to mechanical injury prior to experimentation), an absence of contaminating microglial cells, greater ease of reproducibility of results, lower costs and avoidance of the use of animals. PMID- 9363622 TI - Evidence for the reproductive isolation of Dermacentor marginatus and Dermacentor reticulatus (Acari: Ixodidae) ticks based on cross-breeding, morphology and molecular studies. AB - The species status of Dermacentor marginatus and Dermacentor reticulatus was evaluated by scanning electron microscope (SEM) examination of adult ticks, cross breeding experiments and molecular biological analysis of eggs derived from transspecific pairings. The SEM investigations including the morphometric quantification of phenotypic features resulted in an unequivocal differentiation of adult D. marginatus and D. reticulatus ticks. The cross-breeding experiments demonstrated that irrespective of whether female ticks of both species were applied with con- or transspecific male ticks or without males to sheep, they engorged and laid eggs. The larvae, however, developed only in eggs which originated from conspecific matings. A nested polymerase chain reaction (PCR) of the second internal transcribed spacer (ITS2) using the DNA of eggs from transspecific pairings and sequencing of the PCR products revealed two different genotypes. The genotypes of eggs originating from D. marginatus and D. reticulatus females of these pairings differed. However, the eggs deposited by D. marginatus always possessed the same two genotypes as did the eggs produced by D. reticulatus. These results argue for a strict reproductive isolation of D. marginatus and D. reticulatus and, therefore, for a separate species status. PMID- 9363624 TI - Postmortem skeletal lesions. AB - Postmortem bone alterations are very frequent and can raise the issue of their nature (antemortem, perimortem or postmortem defects). The aim of this work is to study various aspects of defects which were not assessed as perimortem trauma, from a series of 50 defects examined, resulting from 24 forensic cases. This study emphasizes the variability of size, shape and number of postmortem defects. Usually the diagnosis of antemortem defects is helped by a careful examination of some characteristics as the edges of the defects, the areas of discoloration of the edges and of the whole bone. Elsewhere it appears very difficult to know the true nature (antemortem, postmortem, or perimortem alterations) of the bone. PMID- 9363623 TI - Myocardial sarcoidosis as a rare cause of sudden cardiac death. AB - Two relatively young women died suddenly due to myocardial sarcoidosis. Necropsy in both cases revealed compact infiltration of the ventricular septum by fibrous tissue. Histologic sections elucidated extensive granulomatous degeneration and giant cells of the Langhans' and foreign body type without central necrosis of the granulomas. Both women had been entirely free of symptoms, but in the second case of a 35-year-old, who had been 6 months pregnant, an ultrasound sonography of the heart had documented a suspicious area in the ventricular septum interpreted as a scar. Further investigations had been postponed until delivery. Isolated myocardial sarcoidosis should be taken into account as one possible cause of sudden death, especially in young people. PMID- 9363625 TI - Prison suicide in Finland, 1969-1992. AB - BACKGROUND: All prisoners' suicides in Finland during 1969-1992 (n = 184) were studied. METHOD: The data were collected from official documents. RESULTS: Of all prisoners' deaths, 47% were suicides. The rate of suicide among male prisoners was three-fold compared to the normal adult Finnish male population. More than half of those committing suicide had a psychiatric disturbance and one half of them had visited the prison health services because of a psychiatric problem not more than one week before the suicide. Almost one third of the suicides were committed in isolation rooms. Contrary to the findings of many previous studies, there was no concentration of suicides at weekends, on religious holidays, in different seasons nor at the beginning of the confinement. CONCLUSIONS: The most important finding of this study was the common use of health care facilities in the prison just before the suicide. It is important to try to develop the means to recognize suicidal ideation among all prisoners seeking psychiatric care. The surveillance of prisoners in isolation cells needs to tighten up and should probably be continuous. PMID- 9363626 TI - Review of active compression-decompression cardiopulmonary resuscitation (ACD CPR). Analysis of iatrogenic complications and their biomechanical explanation. AB - Our review takes a critical look at the active compression-decompression technique (ACD) for cardiopulmonary resuscitation (CPR). ACD-CPR was developed following a report of successful resuscitation performed by a medical amateur using a household plunger. The efficacy of the principle of active decompression has been demonstrated by animal and human studies. Potential iatrogenic complications from the CardioPump were evaluated only when large clinical trials were already underway. Our prospective analysis of autopsy patients and systematic randomised studies in corpses prove that ACD-CPR using the CardioPump considerably increases the rate of iatrogenic complications and especially of sternum fractures. The experimental use of the CardioPump in corpses and the analysis of a variety of different parameters, especially of the rubber cushion pads mounted in the silicone cup to prevent skin abrasions, revealed a statistically significant correlation between sternum fractures and female sex (P < 0.01) and usage of the rubber cushion pad (P = 0.045). Biomechanical studies showed that the transmission of forces from the CardioPump is greatly dependent on chest shape. The lower the sternum is sunken compared with the surrounding structures, the higher the force which is transmitted via the central area of the device onto the sternum. The rubber cushion pad shortens the distance between CardioPump and sternum by 5 mm and therefore increases the sternal loading. Sex differences in the shape of the sternum and especially the thickness may account for the significant correlation between sternum fractures and female sex. PMID- 9363627 TI - Development of guidelines to designate alleles using an STR multiplex system. AB - We have carried out extensive validation of a multiplex system of 6 STR loci and the Amelogenin sex test to investigate the following characteristics: relative peak areas of heterozygote peaks; non-specific artefacts; stutters caused by slippage of the Taq enzyme; pull-up (an electronic artefact often associated with software). The purpose of this paper is to demonstrate how interpretation guidelines can be formulated by experimentation and analysis using casework samples. Automation allows data relating to band position (in base pairs), peak area and peak height to be easily collected and manipulated in spreadsheets or computer programs. This paves the way to designing expert systems to carry out the interpretative process. PMID- 9363628 TI - A D5S43 (MS8) allele with an internal Hae III restriction site. AB - An allele with internal Hae III restriction site has been found in the D5S43 locus. A three-fragment pattern was detected in a child and its "putative father". Hinf I and Mbo I cleavage revealed only two fragments. It is the first published three-fragment D5S43/Hae III phenotype. PMID- 9363629 TI - The discrimination between overt and non-overt self-inflicted lesions. AB - Injuries following autoaggressive behaviour are found in patients examined in forensic medicine as well as in psychiatric clinics. Self-mutilation often is combined with a borderline personality disorder in psychiatric patients. Our investigation compares injuries and wounds in psychiatric patients and those in persons examined in the Institute for Forensic Medicine after referral by the police. Our intention was to show evident differences and/or conformities in both of these groups. Additionally we describe a 'third group' of patients which has not yet been mentioned. These women showed, at the same time, characteristics of patients with overt self-injuries and of those with non-overt self-injuries. In this 'third group' we can often find a mixture of reality and fantasy/imagination. PMID- 9363630 TI - Combination of fatal digoxin poisoning with endocardial fibroelastosis. AB - This is the first report in the forensic literature of a combination of fatal digoxin poisoning with endocardial fibroelastosis (EFE). Typical morphological features of EFE as the cause of clinically diagnosed cardiomyopathy were present in the autopsy of a 3-year-old girl, including cardiac hypertrophy and marked thickening of the left-sided endocardium, consisting of numerous elastic and collagenic fibres. After exclusion of cardiac and cerebral causes of death, accidental digoxin intoxication was proved. Postmortem toxicological analyses by fluorescence polarization immunoassay (FPIA) disclosed digoxin levels of 71 micrograms/kg (femoral vein blood), 77 micrograms/kg (cardiac blood), 255 and 221 micrograms/kg (cardiac muscle of the right and left chamber), 163 micrograms/kg (psoas muscle), 91 micrograms/kg (lung), 222 micrograms/kg (liver) and 520 micrograms/kg (kidney). The results are compared with the antemortem digoxin concentration of 39 ng/ml serum. The case is discussed from its unusual morphological and toxicological aspects, with special consideration of possible medical malpractice. PMID- 9363631 TI - Protein kinase CK2. AB - Protein kinase CK2 is a ubiquitous protein kinase responsible for the phosphorylation of Ser and Thr residues specified by acidic side chains in many proteins, including several key enzymes, growth factor receptors, transcription factors and cytoskeletal proteins. The holoenzyme is composed of two catalytic and two regulatory subunits, the latter having antagonistic roles. CK2 is constitutively active and its targeting seems to be modulated through association with a variety of cellular proteins (e.g. heat shock protein 90 and p53). CK2 is abnormally elevated in proliferating and neoplastic tissues and recent studies suggest that mice overexpressing CK2 develop leukemia. Specific inhibitors of CK2, currently being developed, may have therapeutic potential. PMID- 9363632 TI - Collagen IX. AB - Collagen IX was identified as a distinct component of cartilage about 10 years ago. Composed of three polypeptide chains, its heterotrimeric molecules are located on the surface of type II collagen fibrils in cartilage. The interaction between collagens II and IX is stabilized by covalent crosslinks. The location of collagen IX molecules on fibril surfaces suggests that they represent macromolecular bridges between fibrils and other matrix components in cartilage, and that collagen IX is important for the cohesive and compressive properties of cartilage. Transgenic mice with mutations in a type IX gene develop normally, but show degenerative changes in articular cartilage after birth. Additional evidence for the importance of collagen IX in human articular cartilage comes from the recent finding that a mutation in one of the collagen IX genes causes multiple epiphyseal dysplasia. The mild complaints in affected individuals with the mutation suggest that mutations in type IX collagen genes may represent genetic risk factors for late onset osteoarthritis. PMID- 9363633 TI - Regulation of CDK/cyclin complexes during the cell cycle. AB - The eukaryotic cell cycle is regulated by the temporal activation of different cyclin-dependent kinase (CDK)/cyclin complexes. Whilst the level of the catalytic subunit of the complex, the CDK, remains relatively constant through the cycle, the level of the cyclin subunit generally oscillates. Cyclins are synthesized, bind and activate the CDK and are then destroyed. In this review, we summarize the current knowledge of the regulation of the cell cycle by CDK/cyclin complexes with special emphasis on new developments in cyclin biosynthesis and destruction, the structural analysis of the CDK/cyclin complexes and the role of a set of inhibitors of CDK/cyclin complexes that are important for the coordination of the different stages of the cell cycle. PMID- 9363634 TI - Ascorbate-dependent expression of ubiquitin genes in guinea pigs. AB - In an attempt to characterize a gene(s), of which the expression is ascorbate dependent, a cDNA fragment encoding ubiquitin was isolated from a subtracted cDNA library constructed from spleen RNAs of ascorbate-deficient or -replete guinea pigs. On Northern blot analysis, three transcripts (1.8 kb ubiX, 1.3 kb ubiY and 0.7 kb ubiZ) were detected. The ubiY encodes four direct repeats of the 76 amino acid ubiquitin sequence with seven additional amino acids, V-Y-A-S-P-I-F, at the C-terminus. The transcript ubiX appears to comprise more than five repeats of the ubiquitin-encoding unit. The ubiZ encodes a ubiquitin monomer fused to an 80 amino acid extension exhibiting 100% amino acid sequence identity to the human homolog, HUMUBA80R. The ubiX gene was expressed animal-dependently. The ubiY mRNA levels decreased under ascorbate-deficient conditions, and increased under ascorbate-replete conditions, whereas ubiZ mRNA remained unaltered at low levels under the feeding conditions used here. PMID- 9363635 TI - Antibodies against high-density lipoprotein binding proteins enhance high-density lipoprotein uptake but do not affect cholesterol efflux from rat hepatoma cells. AB - High-density lipoprotein plays a key role in the reverse cholesterol transport pathway as well as in the delivery of cholesterol to the liver and steroidogenic tissues. Metabolism of high-density lipoprotein is determined by one of its apolipoproteins, apolipoprotein A-I; however, the identity and function of cellular protein which binds high-density lipoprotein remains unclear. The effect of antibodies against rat high-density lipoprotein binding proteins, HB1 and HB2, on high-density lipoprotein metabolism in a rat hepatoma cell line were studied. Cells were preincubated with the antibodies and 125I-labeled high-density lipoprotein binding and uptake as well as cholesterol biosynthesis and cholesterol efflux to human plasma or isolated high-density lipoprotein were studied. Both antibodies reacted specifically with HB1 and HB2 on the ligand and Western blots, but their binding was not blocked by high-density lipoprotein. Both antibodies inhibited 125I-labeled high-density lipoprotein binding to cells by 20-40%, but stimulated 125I-labeled high-density lipoprotein uptake by up to 2.5-fold. The antibodies had no effect on cholesterol efflux or on cholesterol synthesis. It is concluded that high-density lipoprotein binding proteins, HB1 and HB2, may be involved in high-density lipoprotein uptake in the liver rather than in mediating cholesterol efflux. PMID- 9363636 TI - Partial inactivation of chorismate mutase-prephenate dehydrogenase from Escherichia coli in the presence of analogues of chorismate. AB - Chorismate-5,6-epoxide, chorismate-5,6-diol, various adamantane derivatives and 2 hydroxy-phenyl acetate are structural analogues of chorismate that act as competitive inhibitors of both the chorismate mutase and prephenate dehydrogenase activities of the bifunctional enzyme, hydroxyphenylpyruvate synthase. The interactions of these chorismate analogues with both activities of the synthase are investigated further. Chorismate mutase and prephenate dehydrogenase activities were assayed spectrophotometrically at 290 and 340 nm, respectively. Data were fit by non-linear regression to appropriate equations describing the time-dependent formation of product or decay of enzymic activity. In the presence of these chorismate analogues, both the mutase and dehydrogenase activities undergo a time-dependent partial inactivation. Progress curves for synthesis of product by the mutase or dehydrogenase in the presence of chorismate-5,6-epoxide, chorismate-5,6-diol or adamantane-1,3-diacetate resemble time-courses characteristic of slow-binding inhibition. However, if the bifunctional enzyme was preincubated with a chorismate analogue prior to addition of substrate, only a minor proportion of enzymic activity was recovered, excluding the possibility of reversible, slow-binding inhibition. When hydroxyphenylpyruvate synthase binds certain chorismate analogues to form an EI complex, there is a slow conformational transition to an ET complex, which may be susceptible to oxidation leading to partial inactivation. Some protection against this inactivation is provided by high concentrations of dithiothreitol (20 mM), suggesting that the inactivation may be due to chemical oxidation. PMID- 9363637 TI - Purification and partial characterization of an ostrich alpha 1-antichymotrypsin like serum inhibitor. AB - alpha 1-Antichymotrypsin, a member of the serpins, is the predominant plasma inhibitor of neutrophil cathepsin G. The aim of this study was to purify ostrich alpha 1-antichymotrypsin and to compare its biochemical properties with those of other species. Ostrich alpha 1-antichymotrypsin was purified from serum by ammonium sulphate fractionation, QAE-Sephadex C-50 and phenyl-Toyopearl chromatography. N-terminal sequence, amino acid composition, molecular mass, isoelectric point and reaction with cathepsin G, elastase and chymotrypsin were determined. SDS-PAGE revealed a M, of 55,000 for ostrich alpha 1-antichymotrypsin and pI values of 6.8 and 4.1-4.3 were obtained. The amino acid composition revealed 444 residues and the N-terminal sequence of the first 20 residues revealed a homology of 30% when compared with several other alpha 1 antichymotrypsin sequences. Total inhibition of cathepsin G by ostrich alpha 1 antichymotrypsin was found at a 4:1 molar ratio of inhibitor to enzyme which was similar to that found for commercial alpha 1-antichymotrypsin. Immunological studies highlighted the lack of cross-reactivity between ostrich and human alpha 1-antichymotrypsin. The study indicated that ostrich alpha 1-antichymotrypsin like molecule exhibited similar properties to human alpha 1-antichymotrypsin although there were notable differences. PMID- 9363638 TI - Putrescine uptake in rat type II pneumocytes correlates with gamma glutamyltransferase activity. AB - gamma-Glutamyltransferase (gamma GT) is a key enzyme in glutathione metabolism and it is thought also to play a role in the uptake of polyamines such as putrescine. The aim of our study was to investigate if changes in gamma GT activity would alter total putrescine uptake [P(up)(tot)], as well as more specific uptake via the gamma GT pathway [P(up)(gamma GT)]. Forty-eight hours after their isolation, rat type II cells were exposed to 30, 60 or 125 microM L buthionine-[SR]-sulfoximine (BSO) for 3 hr; 200 or 800 microM tertiary butylhydroperoxide (t-BOOH) for 40 min; 10, 100 or 1000 microM paraquat (PQ) for 1 hr; and 60 or 85% O2 for 48 hr. The gamma GT activity, P(up)(tot) and P(up)(gamma GT) (assessed by inhibiting gamma GT) were measured immediately after the exposure to hyperoxia, or 24 hr after treatment with BSO, t-BOOH or PQ. From previous studies, it is known that these experimental conditions increased (BSO, 200 microM t-BOOH) or decreased (800 microM t-BOOH, PQ, hyperoxia) gamma GT activity. There was a strong correlation between the changes in gamma GT activity and the changes in P(up)(gamma GT) (r = 0.81, p < 0.001). These findings support the hypothesis that gamma GT partly regulates the uptake of putrescine, one of the polyamines required for cell growth and differentiation. PMID- 9363639 TI - Purification and characterization of proteasome from ostrich liver. AB - The proteasome (EC 3.4.99.46) is a high molecular mass (approximately 700 kDa) multisubunit enzyme complex which is the focus of worldwide research in order to identify the structure, mechanism of action and specificity of the complex. The purpose of the present study was to investigate the tryptic, chymotryptic and peptidylglutamyl-peptide hydrolysing (PGPH) activities of ostrich liver proteasome. The proteasome was purified from ostrich liver by employing ammonium sulphate fractionation, followed by three sequential chromatographic steps on Toyopearl Super Q-650 S, Sephadex G-150 and phenyl-Toyopearl columns. Temperature and pH optima were examined and the effect of inhibitors, detergents, fatty acids and cations on the peptidase activities was determined. Ostrich proteasome exhibited a relative M(r) of approximately 665,000 using non-denaturing gradient PAGE and dissociated into the characteristic "ladder" associated with the proteasome subunits during SDS-PAGE. The pH optima for the peptidase activities were found to be slightly alkaline (tryptic activity) and neutral (chymotryptic like and PGPH activities). Ostrich liver proteasome was found to be activated in terms of the PGPH activity by fatty acids and SDS, whereas the chymotryptic and tryptic-like activities were differentially inhibited. Ostrich proteasome, in its inhibition by monovalent cations, was similar to the proteasomes extracted from other sources. The specificity of the proteasome appears to be very broad, although it lacks aminopeptidase activity. The yield compared favourably with similar extraction procedures which have been reported. On the basis of the physicochemical and kinetic properties which ostrich liver proteasome exhibited, it can be safely concluded that it corresponds well with the proteasomes isolated from many other sources. PMID- 9363640 TI - Effect of glutathione deficiency on the adipocyte Mg(2+)-dependent phosphatidate phosphohydrolase. AB - Previous studies from this laboratory [Jamdar S. C. and Cao W. F. (1994) Biochem. J. 301, 793-799] show that the adipocyte Mg(2+)-dependent phosphatidate phosphohydrolase (MGPPH), a major regulatory enzyme in adipose triacylglycerol metabolism, requires an active thiol group for its activity and perturbation of this group results in the loss of enzyme activity. Since glutathione (GSH) is important in maintaining the intracellular thiol state, we have used GSH deficient animals and adipocytes to test the possibility that intracellular GSH concentration is critical in controlling the MGPPH activity. The MGPPH was measured in the presence of aqueous dispersed phosphatidate, and the release of P1 was taken as a measure of enzyme activity. The GSH deficiency in animals and isolated adipocytes was produced in the presence of diethylmaleate (DEM) or buthionine sulfoximine (BSO). Intraperitoneal administration of BSO into animals (3 mmoles/kg) showed 10-25% reduction in the blood and adipose GSH and 25% decline in the adipose MGPPH activity. However, DEM (0.3 ml/kg) was more effective and caused over 70% reduction of the blood and adipose tissue GSH content and 75% decline in the adipose MGPPH activity within 4 hr of drug administration. After 24 hr, these values returned to normal. Adipocytes incubated with 2.5 mM DEM for 60 min at 37 degrees C also showed a significant reduction in the GSH content and the MGPPH activity present in the cytosol and membrane fractions. The loss of membrane MGPPH was associated with decreased rates of triacylglycerol formation from [14C]palmitate. Pre-incubation of adipocyte homogenates with 1 mM DEM also resulted in > 90% decline in the MGPPH activity, which was preventable in the presence of GSH and dithiothreitol. Therefore, these studies suggest that the sulfhydryl environment offered by glutathione is critical for the maintenance of adipocyte MGPPH activity. PMID- 9363641 TI - The role of the Src homology-2 domain in the lethal effect of Src expression in the yeast Saccharomyces cerevisiae. AB - Expression of the retroviral transforming gene v-src arrests the proliferation of the yeast Saccharomyces cerevisiae. A functional Src SH2 (Src homology 2) domain is required for this arrest. To examine the mechanism by which Src blocks yeast cell proliferation, and to determine the role of the Src SH2 domain in the growth arrest, src variants were expressed in yeast under the control of the galactose inducible GAL1 promoter. Following galactose induction of Src expression, phosphotyrosyl-proteins were isolated by immunoprecipitation with beads coupled to either anti-phosphotyrosine antibody or to a recombinant fusion protein containing the Src SH2 domain. A group of SH2-binding phosphotyrosyl proteins was detected in cells expressing toxic forms of Src, but were not detected in cells expressing non-toxic variants. This group of phosphotyrosyl-proteins represents a minor subset of the proteins phosphorylated by v-Src. The lethality of v-Src and the phosphorylation of SH2-binding proteins were co-ordinately affected by alterations in phosphotyrosine-phosphatase activity. These observations indicate that the lethality of Src is correlated with the phosphorylation of proteins that bind to the Src SH2 domain. The role of the SH2 domain in determining the lethal effects of Src in yeast may be similar to its role in targeting Src to substrates necessary for its biological effects in vertebrate cells. PMID- 9363642 TI - Immunologic and autoradiographic localisation of the Na+, K(+)-ATPase in articular cartilage: upregulation in response to changes in extracellular Na+ concentration. AB - The maintenance of a relatively low intracellular Na+:K+ ratio is essential for the functioning of a wide range of cellular processes, and is achieved principally by the activity of the membrane-bound Na+, K(+)-ATPase. Chondrocytes, the cells of articular cartilage, exist in an ionic environment where the free extracellular [Na+] is higher (250-400 mM) than that of most other tissues (approximately 140 mM) owing to the fixed negative charges on glycosaminoglycans in the extracellular matrix. This can increase further during static joint loading when fluid expression occurs. To determine aspects of how chondrocytes regulate their ionic composition, in this study, the in situ distribution, pattern of isoform expression and density of the Na+, K(+)-ATPase within cartilage has been investigated. The density of the Na+, K(+)-ATPase was found to be high in the mid-zone, but lower in the surface and deep zones. Immunofluorescence microscopy using monoclonal antibodies to the catalytic alpha subunits of the Na+, K(+)-ATPase revealed the expression of isoforms alpha 1 and alpha 3. Alterations to the extracellular [Na+] (from 80-220 mM, or 120-220 mM) significantly elevated Na+, K(+)-ATPase density of in situ chondrocytes. The results indicate that the Na+, K(+)-ATPase is abundantly expressed in articular chondrocytes and its density is sensitive to the extracellular [Na+]. The expression of the alpha 3 isoform is surprising for a non-neuronal cell, and may indicate a physiological adaptation to the unusually high extracellular [Na+] to which chondrocytes are exposed in the extracellular matrix of cartilage. PMID- 9363643 TI - Unusual effect of clusters of rare arginine (AGG) codons on the expression of human interferon alpha 1 gene in Escherichia coli. AB - The human interferon (hIFN alpha 1) gene contains 11 arginine (Arg) codons AGG or AGA, which are extremely rare for bacteria, four of which are organized in tandems. The two AGG tandems (corresponding to Arg12 Arg13 and Arg163 Arg164) are known to inhibit the translation of hIFN alpha 1 mRNA and therefore they are considered to be responsible for the poor expression of hIFN alpha 1 gene in bacterial cells. To study the effect of these two tandems on the expression of hIFN alpha 1 in E. coli, four new gene variants were designed to contain preferential Arg codons (CGT) substituted for the rare AGG codons in either the first, the second or both AGG tandems. We found that, whereas the yield of hIFN alpha 1 protein per cell remained unchanged, the level of hIFN alpha 1 mRNA decreased gradually (by a factor of two) with the consecutive substitution of the first, second and both AGG tandems. These results indicated, first, that the AGG clusters might have a stabilizing effect on the mRNA, and second, that mRNAs devoid of such clusters were translated at a higher rate in vivo. The protein products of the four genes (having the same amino acid sequence) showed different specific antiviral activity. The most active was the product of gene hIFN alpha 1(c) in which the second AGG tandem (corresponding to Arg163, Arg164) was preserved while the least active was the protein of gene hIFN alpha 1(d) (devoid of both AGG clusters). The role of the AGG tandems in folding of the gene product is discussed. PMID- 9363644 TI - Interleukin-1 beta and interleukin-6 stimulate 2-methylaminoisobutyric acid uptake in HepG2 cells. AB - The metabolic response to inflammation involves an increased uptake of amino acids in the liver. It has been suggested that cytokines, such as interleukin-1 beta and interleukin-6, could be involved in this increased amino acid uptake. We investigated the role of these two inflammatory cytokines in regulating hepatic amino acid transport systems in the human hepatoma cell line, HepG2. Uptake of methylaminoisobutyric acid, the most specific known substrate of system A, and of glutamine, both transported by other sodium-dependent transport systems ASC and N, was assayed after incubation of the cells for various times with cytokines, using the cluster-tray method. Interleukin-1 beta and interleukin-6 (1000 U/ml) stimulated methylaminoisobutyric acid uptake by 36 +/- 6 and 41 +/- 4%, respectively (per cent +/- SD, n > or = 6). Under our experimental conditions, these cytokines had no effect on glutamine uptake. The stimulatory effect on methylaminoisobutyric acid uptake was not increased by combining the cytokines or by the presence of dexamethasone. The cytokine effect was abolished by cycloheximide, suggesting the involvement of de novo protein synthesis in this activation of transport system A. These data demonstrate that, in our culture conditions, interleukin-1 beta and interleukin-6 indirectly exert a stimulatory effect on methylaminoisobutyric acid transport in HepG2 cells. PMID- 9363645 TI - Methacrylate uptake by isolated hepatocytes and perfused rat liver. AB - I showed recently (Int. J. Biochem. Cell Biol. 27, 1311-1316, 1995) that methacrylate formed in vivo from methyl methacrylate (a basic component of polymer used in medicine and industry) is very efficiently removed from the blood. To resolve whether the liver is responsible for methacrylate elimination from the blood, methacrylate uptake by isolated hepatocytes and by perfused liver was investigated. For comparative purposes methacrylate uptake by perfused heart was also examined. It has been found that methacrylate is eliminated efficiently both by isolated hepatocytes and by perfused liver. The whole liver eliminated more than 100-fold of this compound compared to the whole heart. If the rate of methacrylate uptake was calculated per gram of tissue, the liver was 10 times more effective than the heart. KCN (2 mM) addition inhibited methacrylate uptake both by the liver and the heart by approximately 40% at 20 min of perfusion. Pretreatment of rats with galactosamine, which causes liver damage, resulted in a significant inhibition of methacrylate uptake. The data presented in this paper suggest that the liver plays a central role in the methacrylate elimination from the blood. From the results published recently and presented in this paper one can conclude that the relatively low toxicity of orally administered methyl methacrylate is the consequence of a rapid ester hydrolysis with the subsequent elimination of methacrylate by the liver. The toxicity of methacrylate (especially towards organs other than the liver) could be increased under conditions leading to liver damage. PMID- 9363646 TI - Opossum kidney (OK) cells in culture synthesize and degrade the natriuretic hormone dopamine: a comparison with rat renal tubular cells. AB - To explore further the usefulness of opossum kidney (OK) cells in the study of renal dopaminergic physiology, we have undertaken the study of aromatic L-amino acid decarboxylase (AAAD), catechol-O-methyltransferase (COMT) and type A and B monoamine oxidase (MAO-A and MAO-B), the main enzymes involved in the synthesis and degradation of dopamine. The Vmax values for AAAD, using L-DOPA as the substrate, in rat renal tubular cells were found to be significantly (P < 0.01) higher (120-fold) than in OK cells. However, K(m) values in OK cells (1.1 mM [0.3, 1.9]) were similar to those observed in rat renal tubular cells (K(m) = 1.0 mM [0.8, 1.2]). The Vmax values for COMT (in nmol/mg protein/30 min) in OK cells (2.1 +/- 0.2) were similar to those in the rat renal tubular cells (1.6 +/- 0.1), whereas K(m) values in OK cells (2.3 microM [0.1, 4.5]) differ considerably (4.8 fold, P < 0.01) from those in rat renal tubular cells (11.2 microM [9.2, 13.1]). The Vmax values (in nmol/mg protein/20 min) for deamination of [3H]-5 hydroxytryptamine, the specific MAO-A substrate, was similar in rat renal tubular cells (12.4 +/- 1.0) and OK cells (12.9 +/- 1.1); K(m) values also did not differ between these two preparations. In contrast to rat renal tubular cells, deamination of [14C]-beta-phenylethylamine, the substrate for MAO-B, in OK cells was found to be non-saturable and to represent less than 10% of that observed in homogenates of rat tubular cells. In conclusion, OK cells in culture are endowed with the synthetic and metabolic machinery needed to form and degrade dopamine. The amounts of the enzymes AAAD, COMT and MAO-A found in this cell line are likely to be sufficient to reproduce, under in vitro conditions, the environment in which the renal dopaminergic system normally operates. PMID- 9363647 TI - Kinetics and role of alpha 1-acid glycoprotein-dependent osmotic transport of water and ions in palmitoyl-L-oleoyl phosphatidylcholine liposomes. AB - alpha 1-Acid glycoprotein isolated from human blood plasma is known to influence cell permeability, although the mechanisms of this process are unclear. Here, the glycoprotein effects on the permeability of osmotically stressed phospholipid liposomes are studied as a model of membrane permeability. Liposomes containing glycoprotein were found to be osmotically sensitive to water and chloride salts of some monovalent (Na+, K+) and bivalent (Mg2+, Ca2+) ions. The permeations of these substances were determined by light-scattering measurements of the volume changes in liposomes after mixing with hyperosmotic solutions of chloride salts. The time courses of scattered light were recorded by means of stopped-flow spectrophotometry. Two processes were studied: the fast water outflow from liposomes and slower ion permeations through the lipid membrane. The second order permeation rate constants were determined at different glycoprotein concentrations for both processes. Values from 66 to 250 x 10(3) for water outflow and 2-500 M-1 sec-1 for the different ion permeations were obtained in order to characterize the permeations of solutes across the lipid membrane. The apparent activation energies also were calculated between 18 and 33 degrees C. The mercurial sulphydryl reagent pCMBS inhibited the ion permeations in the slow phase. When pCMBS was present in this phase, higher activation energies were obtained, indicating more difficult permeations. An interpretation of these results is that membrane permeability is mediated by aqueous pores. Membrane selectivity to monovalent metal ions also was demonstrated, but no correlation was observed between the ion radius of the corresponding metal cation and permeation rate constants. The discovery of non-specific pores in liposomes containing glycoprotein shows that they can serve as vehicles for the water and ions in the processes of passive transport through lipid membranes. PMID- 9363648 TI - In vitro tissue-digesting properties of krill enzymes compared with fibrinolysin/DNAse, papain and placebo. AB - Wound debridement, the removal of necrotic tissue, can be achieved with proteolytic enzymes. Recently, a new multi-enzyme preparation, krill enzyme, isolated from Antarctic shrimp-like organisms (Euphausia superba), was reported to possess powerful proteolytic activity towards protein substrates. In this paper, we study the in vitro digestive properties of krill enzymes towards whole tissue, compared with placebo, papain, and fibrinolysin/DNAse. Freshly obtained skin specimens were exposed for 3 days to krill enzymes (3; 0.6 and 0.06 U/ml), papain (120; 60; 6 and 0.6 U/ml), fibrinolysin/DNAse (2.5/1500 E and 1/600 E), and phosphate-buffered saline control solution. Tissue digestion was estimated by measuring wet wt, dry wt, and histological examination. After 72 hr of exposure to 3 U/ml krill enzymes, the dry wt of the specimens was reduced to 2.7% +/- 1.9 (SEM, n = 5), compared with 31.0% +/- 2.7 for placebo, 25.7% +/- 2.5 for 120 U/ml papain, and 24.5% +/- 3.3 for 2.5/1500 E/ml fibrinolysin/DNAse. The differences between krill enzymes and fibrinolysin/DNAse, papain, and control solution were statistically significant (p < 0.007). These data suggest that krill enzymes are more active than other commonly available proteolytic agents used for wound debridement. PMID- 9363649 TI - Nasopharyngeal colonization with Haemophilus influenzae type b among infants and children in Japan. AB - Healthy carriers of Haemophilus influenzae type b (Hib) play an important role in the spread of invasive Hib disease. The aim of the present study was to estimate Hib colonization among infants and children in Japan. Specimens from throat and nasopharyngeal cultures were obtained by thorough swabbing of both tonsils and the posterior pharynx. Specimens were inoculated on Hib antiserum agar. This was prepared with Levinthal base and Hib antiserum. Conventional methods were used concomitantly. Four of 474 infants from 1-48 months of age (0.84%) had Hib cultured from their nasopharynx. The carriage rate in 1-12 months old infants was 0.62% (2/322 cases), and that in 13-48 month old children was 1.32% (2/152 cases). Five of 167 (3.0%) 13-year-old children, and five of 154 (3.2%) 9-year old children were asymptomatic carriers. Thirty-five of 104 household contacts of a patient with invasive Hib disease (33.6%) had Hib colonization. The carriage rate in healthy Japanese children may not be different from that in the USA prior to the availability of the conjugate Hib vaccine. The Hib carriage rate in household contacts of patients with invasive Hib disease was higher than in healthy children (P < 0.005). Our results suggest the possibility of an outbreak of invasive Hib disease in Japan. PMID- 9363650 TI - Minimization of the number of pregnant women to be treated with preventive procedure against GBS infection by means of antibody measurement. GBS Infection Group. AB - To study preventive strategies, it is essential to screen pregnant women having group B Streptococcus (GBS) infection in the birth canal. For the purpose of studying preventive measures against this infection, nationwide multicenter research was performed in GBS-carrying pregnant women. Of a total of 10,267 pregnant women, 1860 cases (18.1%) had GBS. The most common serotypes of detected GBS were type NT6 and JM9, followed by type III, type Ia and then type Ib. Type specific antibody titer was below the cut-off point of 10 units/mL in 30.9% of Ia carriers, 58.5% of Ib carriers, 45.9% of II carriers and 32.9% of III carriers. Fortunately, no neonatal GBS infection occurred during this research. We concluded that 18.1% of studied pregnant women were GBS carriers and one-third of these GBS carriers required preventive procedures with antibody measurement. PMID- 9363651 TI - Second generation hepatitis C virus antibody-positive rate in children: investigation of the route of hepatitis C virus infection in children with no history of transfusion. AB - Hepatitis C virus (HCV) antibody and HCV-RNA screening was undertaken in 1864 children, aged from 0 to 15 years who did not have a history of transfusion. Anti HCV was tested by the second generation enzyme-linked immunosorbent assay (ELISA). HCV RNA was examined by reverse transcriptase-nested polymerase chain reaction (PCR). Two of the 1864 children were positive for serum HCV RNA. They had no history of transfusion, no episodes of horizontal transmission, but the mother in each case was positive for serum HCV RNA, implying mother-to-infant infection. Eleven children who were positive for HCV antibody with low values and negative for serum HCV RNA were classified as belonging to the high bovine milk (composed primarily of casein)-specific IgG4 value group. This suggested that many of the children who were falsely positive for HCV antibody using ELISA had antibodies to casein. PMID- 9363652 TI - Interferon therapy for Japanese hemophiliacs with chronic hepatitis C. AB - Eight Japanese hemophiliacs with chronic hepatitis C (CHC) received interferon (IFN) therapy and four of them (50%) responded completely. Non-responders included 3 double-infected patients: 1 with hepatitis B virus (HBV) and 2 with human immunodeficiency virus-1 (HIV-1). In one of the patients with HIV-1 double infection, the absolute number of CD4+ lymphocytes decreased during IFN therapy. These findings suggest that hemophiliac patients with CHC can respond well to IFN therapy, but in patients who are double-infected with HBV and HIV-1, the indication of IFN therapy should be considered seriously. PMID- 9363653 TI - Problems on the diagnosis of sudden infant death syndrome. AB - Various autopsy cases of sudden unexpected death (SUD) in infancy were examined at the Tokyo Medical Examiner's Office between 1985 and 1994. More than half of the SUD were diagnosed as sudden infant death syndrome (SIDS), but a number of other causes, such as mechanical asphyxia, were also diagnosed. SIDS is diagnosed by autopsy, but there are no clear diagnostic criteria differentiating SIDS from other causes of SUD. SUD is diagnosed as SIDS when other causes are excluded, but it is difficult to distinguish between SIDS and mechanical asphyxia. There was not a large difference in autopsy findings, or in death scene or statistical data, between SIDS and non-SIDS cases. In their estimation of the diagnostic ratio of SIDS to other causes of death, medical examiners might be divided into three groups: 'SIDS tolerationist' examiners think that SUD should be positively diagnosed as SIDS, insofar as another cause of death is not proved clearly. A second group of examiners might be regarded as 'SIDS exclusionist': these consider microscopic findings or peculiar death scenes as important contributing factors leading to death. The third group represents a middle stance somewhere between these two. We thought that (forensic) pathologists as well as medical examiners in Japan might have differing stances on SIDS diagnosis. The statistical analysis of SIDS in certain research areas may be affected by the diagnostic 'preference' of pathologists belonging to a certain institute. PMID- 9363654 TI - Platelet activation in congenital heart diseases. AB - The research presented here investigated platelet activation in cyanotic and acyanotic congenital heart diseases (CHD). Children with cyanotic CHD are prone to both thrombosis and hemorrhage. However, patients with acyanotic CHD may also have a mild bleeding disorder. The platelet activation in CHD was investigated in support of a hypothesis that platelet activation may play a role in the hemostatic abnormalities reported in these patients. Platelet activation was determined by using flow cytometry with anti-CD62 monoclonal antibody (mAb), which has been shown to be a specific marker of platelet activation. Thirteen children with cyanotic CHD, 33 children with acyanotic CHD and 17 healthy children serving as controls were studied. Platelet activation was significantly higher in the cyanotic group and also in the acyanotic group compared with the healthy children (P = 0.0000 and P = 0.019, respectively). In the cyanotic group, platelet activation showed a direct correlation with arterial O2 saturation (SaO2) (P = 0.014). There was no correlation between platelet activation and erythrocyte related parameters in either group. Platelet activation occurs in CHD, particularly in patients with cyanotic CHD (even in patients with no evidence of clinical thrombosis) and it may play a role in the pathogenesis of thrombotic disorders seen in these patients. PMID- 9363655 TI - Role of adenosine in the diagnosis and treatment of tachyarrhythmias in pediatric patients. AB - Tachyarrhythmias are common rhythm disturbances in infants and children. Despite the availability of diagnostic criteria arrhythmias are sometimes commonly misdiagnosed. Recent reports suggest that an endogenous purine nucleoside, adenosine, has a diagnostic effect in narrow QRS complex tachycardias, in addition to terminating supraventricular tachycardia involving the atrioventricular node. This report reviews the authors' experience with the use of adenosine for diagnosis of narrow and wide complex tachyarrhythmias in children. Adenosine was administered to 43 patients with several types of tachyarrhythmias (mean age, 8.3 +/- 5.24 years). Nineteen patients had structural or acquired heart disease. Of the 43 patients there were 28 (65%) several different types of narrow QRS complex tachycardia and 14 (33%) ventricular arrhythmias. One patient (2%) had long QT. Adenosine terminated supraventricular tachycardia, in 11 of 12 patients (92%), ventricular tachycardia in five of eight patients (63%), and transiently terminated premature ventricular contractions in two of six patients (33%). The diagnostic ability of adenosine was perfect in eight supraventricular tachycardia. In these eight cases the tachycardia mechanism was unclear before the administration of adenosine, which demonstrated three cases of sinus tachycardia, three of atrial flutter, one of atrial fibrillation and one of atrial fibrilloflutter. Confirmation of the primary diagnosis by adenosine was perfect in five tachyarrhythmias including three cases of atrial flutter, one of atrial fibrillation and one of ectopic atrial tachycardia. The average effective dose of adenosine was 212 micrograms/kg (range, 100-400 micrograms/kg). There were no serious side-effects except transient dyspnea, chest pain and flushing. These findings demonstrate adenosine to be helpful and safe in the diagnosis of tachyarrhythmias. PMID- 9363656 TI - Comparison of synchronized and conventional intermittent mandatory ventilation in neonates. AB - Between October 1993 and April 1995, a total of 77 neonates requiring mechanical ventilation were enrolled in this study and were randomly divided into two groups. Group A consisted of 31 premature infants (mean birthweight 1.36 +/- 0.29 kg) with respiratory distress syndrome (RDS) and seven neonates (mean birthweight 3.2 +/- 0.5 kg) with meconium aspiration syndrome (MAS). Group B consisted of 31 premature infants (mean birthweight 1.31 +/- 0.3 kg) with RDS and eight neonates (mean birthweight 3.3 +/- 0.5 kg) with MAS. Infants in group A received synchronized intermittent mandatory ventilation (SIMV) and infants in group B received conventional intermittent mandatory ventilation (CIMV) therapy. In premature infants with RDS, our data showed: (i) the duration of ventilation was significantly shorter (P < 0.05) in the synchronized group (156 +/- 122 h) compared to the conventional group (242 +/- 175 h); (ii) significantly fewer (P < 0.05) patients required reintubation in the synchronized group than in the conventional group (three vs 11 patients); (iii) incidence of severe intraventricular hemorrhage (grades 3 and 4) was significantly lower (P < 0.05) in the synchronized group compared to the conventional group (one vs seven patients); (iv) incidence of bronchopulmonary dysplasia was significantly lower (P < 0.05) in the synchronized group than in the control group (one vs seven patients). In neonates with MAS, our data showed no significant difference (P < 0.05) on duration of ventilation, incidence of reintubation, incidence of pneumothorax or mortality rate between synchronized and control groups. PMID- 9363657 TI - Correlation between deletion patterns of SMN and NAIP genes and the clinical features of spinal muscular atrophy in Japanese patients. AB - We conducted molecular analysis of two candidate genes for spinal muscular atrophy (SMA), the survival motor neuron gene (SMN) and the neuronal apoptosis inhibitory protein gene (NAIP), in 16 Japanese patients with SMA and compared the phenotypic features of SMA in these patients with the corresponding genotypes. Exons 7 and/or 8 of SMN were homozygously deleted in 11 SMA type I (Werdnig Hoffmann disease) patients, two SMA type II patients and one SMA type III patient. Exons 5 and 6 of NAIP were homozygously deleted in six SMA type I patients. No patient had a deletion in NAIP without a deletion in SMN. Mechanical ventilation was required during the first 7 months of life in the SMA type I patients who had a deletion in both SMN and NAIP. Ventilatory support was initiated within 2 years after birth in patients who had a deletion in SMN but not in NAIP. We detected homozygous deletion of exon 5 of NAIP in the unaffected mothers of two SMA type I patients. In these families, the patients exhibited a deletion in both SMN and NAIP. The parents and unaffected siblings of these patients did not have a deletion in SMN. The present findings support the hypothesis that SMN deletion plays an important role in the development of SMA and suggest that combined deletion of both SMN and NAIP may be relevant for determining the disease severity. PMID- 9363658 TI - p21 (WAF1/Cip1/Sdi1/Pic1) mRNA is expressed in neuroblastoma cell lines but not in Ewing's sarcoma and primitive neuroectodermal tumor cell lines. AB - The p21 protein inhibits the activity of cyclin-Cdk complexes and suppresses cell cycle progression. Wild type p53 can induce p21, but mutated p53 cannot. Previous studies have demonstrated that mutation of p53 is absent in neuroblastoma (NB). These reports prompted us to examine whether p53 induced p21 in NB. We examined the expression of p21 and p53 mRNA in eight NB, two Ewing's sarcoma (ES) and two primitive neuroectodermal tumor (PNET) cell lines by Northern blot analysis, and sequenced p53 cDNA of these cells. Although p53 mRNA was detected in all analyzed cell lines by Northern blot analysis, p21 mRNA was detected in six NB but not in two NB, two ES and two PNET cell lines. We detected the point mutation of p53 at codon 273 (CGT to TGT) in one NB and two ES cell lines. The non-transforming substitution at codon 72 (CCC to CGC) was detected in all analyzed cell lines. One PNET cell line had a large deletion of p53 cDNA. These results showed that p21 mRNA was usually expressed in NB but not in ES and PNET. This may suggest that the down stream of the p53 signal transduction pathway in NB is different from that of the closely related tumors of ES and PNET. PMID- 9363659 TI - Extrahepatic portal venous obstruction in childhood: etiology, clinical and laboratory findings and prognosis of 34 patients. AB - Extrahepatic obstruction of the portal vein is a well known cause of portal hypertension in childhood, that causes severe morbidity. We evaluated 34 children (24 boys, 10 girls, age 4.5 months to 12 years, mean 5.5 +/- 3.8 years) with this diagnosis, to define the clinical picture, laboratory changes, diagnostic tools and therapeutic modalities. Gastrointestinal bleeding was the commonest mode of presentation (64.7%), with the second being splenomegaly. The cause of the obstruction could be determined in 38.2% (13/34) of the subjects. At the beginning of the study the main diagnostic procedure was splenoportography although in more recent years pulsed duplex Doppler ultrasonography has been used. The follow up period was median of 5 years (range 1-11 years). The mean number of bleeding episodes was 4.7 +/- 5.9 (range 1-26), while nine patients never bled. There was no mortality. Ten patients underwent surgery, while sclerotherapy was performed on 10. Twenty-one patients received beta-blocker drugs. No difference was found among these therapeutic modalities. It is well established that the major risk for children with extrahepatic portal vein obstruction is gastrointestinal bleeding which is tolerated quite well. Surgery should be indicated only in children where bleeding cannot be controlled by medical means including sclerotherapy. PMID- 9363660 TI - Genetic analysis of isolated persistent hypermethioninemia with dominant inheritance. AB - We describe a type of mild hypermethioninemia due to a point mutation in the MATA1 gene, which was inherited dominantly in a family. Three patients coming from the same family pedigree were detected by the presence of isolated hypermethioninemia on a mass-screening program. The measurement of methionine adenosyltransferase (MAT) activity in a patient's liver revealed a partial deficiency of hepatic MAT with a reduction in the Km for methionine. Single strand conformation polymorphism (SSCP) analysis and direct sequencing of the patients' genomic DNA revealed a G to A mutation at nucleotide 791 that converts Arg-264 to His (R264H) in one allele of MATA1 gene. The other allele was normal in all the patients examined. Gene tracking in the family revealed that the hypermethioninemia is associated with heterozygosity for the R264H mutation in the MATA1 gene. PMID- 9363662 TI - Transient erythrophagocytosis in Diamond-Blackfan anemia. AB - We report on a 4-month-old Japanese infant girl with Diamond-Blackfan anemia (DBA) as shown by congenital macrocytic pure red cell hypoplasia with marked reduction of erythroid precursors in bone marrow, reticulocytopenia, increased fetal hemoglobin, and elevated adenosine deaminase activity in peripheral blood. She responded poorly to conventional doses of corticosteroids, however, with high dose corticosteroids she responded with reticulocytosis and an elevation of hemoglobin level above 12 g/dL. Erythrophagocytosis was noted during the tapering period of prednisone when her hemoglobin level declined to 7.6 g/dL and reticulocyte level to 0.4%. At that time, the erythrophagocytosis was noted in about 60% of marrow histiocytes. These findings were not observed prior to or during the high dose prednisone therapy. We speculate that one of the causes of pure red cell aplasia and reticulocytopenia in DBA is mediated by erythrophagocytosis. PMID- 9363661 TI - Magnetic resonance imaging of the cauda equina in two patients with Guillain Barre syndrome. AB - The results are presented of magnetic resonance imaging (MRI) of the spine in two cases of childhood Guillain-Barre syndrome. After injection of gadolinium diethylenetriamine pentaacetic acid, MRI showed enhancement of the cauda equina in these patients. These MRI observations may help confirm the diagnosis of Guillain-Barre syndrome. The nerve root enhancement resolved as the clinical symptoms improved. Serial imaging may be useful in monitoring the response to therapy and assessing new treatment regimens. It may also yield a better understanding of the disease process. PMID- 9363663 TI - A case of X-linked alpha-thalassemia/mental retardation syndrome: analysis of hemoglobin by an automated glycated hemoglobin analyzer. AB - A 5-year-old male patient with X-linked alpha-thalassemia/mental retardation syndrome is reported. He showed multiple minor anomalies including characteristic facial abnormalities, alpha-thalassemia, severe mental retardation, and hypogonadism. Analysis of his hemoglobin by high performance liquid chromatography using an automated glycated hemoglobin analyzer revealed an abnormal peak. Identification of an abnormal peak by an automated glycated hemoglobin analyzer will aid in the diagnosis of patients with X-linked alpha thalassemia/mental retardation syndrome. PMID- 9363664 TI - Acute disseminated encephalomyelitis exacerbated by varicella. AB - The actual incidence of central nervous system complications with varicella ranges from 0.1 to 0.7% in several series and the time interval between the rash and the type of neurological manifestation varies widely. Cerebellar ataxia and hypotonia are the most common neurological abnormalities associated with varicella. We present a report on a 6-year-old girl with an unusual course of disease finally presenting a probable diagnosis of acute disseminated encephalitis. PMID- 9363665 TI - Imipenem for treatment of relapsing Salmonella meningitis in a newborn infant. AB - Salmonella meningitis is a rare clinical entity that occurs mainly during early infancy. Treatment of Salmonella infections may be complicated by the bacteria's growing resistance to clinically important antimicrobial agents, especially third generation cephalosporins. A report is presented of a newborn infant with Salmonella meningitis who relapsed after 4 weeks of cefotaxime treatment and was cured completely with imipenem cilastatin therapy. PMID- 9363666 TI - Enalapril-induced anemia in a renal transplant patient. AB - Side-effects of angiotensin converting enzyme (ACE) inhibitors, such as a slight decrease in hematocrit, are increasingly being reported. A 14-year-old renal transplant patient on enalapril therapy developed anemia with reticulocytosis. She was investigated for other causes of anemia and enalapril therapy was ceased. Her hemoglobin level increased and reticulocyte count decreased after cessation of therapy. No other cause of anemia was found. Although anemia in patients receiving ACE inhibitors such as enalapril has previously been reported, this is the first reported patient who developed anemia associated with mild reticulocytosis and macrocytosis. PMID- 9363667 TI - Ganglioneuroma of left adrenal gland in a patient with Turner syndrome during growth hormone therapy. AB - We report on a Japanese girl with Turner syndrome (45,XO) who developed ganglioneuroma of the left adrenal gland during growth hormone (GH) therapy. She had received GH replacement therapy from the age of 6.8 years. At the age of 10.3 years, abdominal ultrasonography revealed a mass which occupied the upper area of her left kidney. Computed tomography and magnetic resonance imaging of the abdomen showed a low density mass with a smooth surface located between the upper portion of the left renal vein and the pancreas. Microscopic examination resulted in a diagnosis of ganglioneuroma of the left adrenal gland. At present we cannot conclude that patients who have received GH replacement therapy are at higher risk for developing tumors compared to those without GH replacement therapy. PMID- 9363668 TI - A case of ambiguous genitalia with unilateral amelia and unilateral peromelia of the upper limbs. AB - A 7-year-old patient is reported with a 46,XY karyotype, ambiguous genitalia and unilateral amelia and unilateral peromelia of the upper limbs. The external genitalia had essentially a female configuration with labia majora, large clitoris, and narrow vaginal opening. Gonadal tissue was not palpable on either side. The levels of 17-OH progesterone dehydroepiandrosterone sulfate (DHEA-S), androstenedione and luteinizing hormone (LH) were normal, but the level of follicle stimulating hormone (FSH) was elevated minimally. Abdominal ultrasonography (USG) was normal. On pelvic USG, neither uterus nor ovaries were seen. Genitography showed a blind vagina. Gonads, Mullerian and/or Wolffian structures were not observed at laparotomy. Clitoral recession and cut-back vaginoplasty were performed. The occurrence of these findings suggests embryonic testicular regression syndrome with bilateral transverse defect of the upper limbs. The case has been presented because the pattern of the birth defects, including both ambiguous genitalia and unilateral amelia on one side of the upper limbs and unilateral peromelia on the other, have not been described previously. PMID- 9363669 TI - Familial atrial septal defect with prolonged atrioventricular conduction. AB - A family is described in which a mother, her two children and another two relatives all had atrial septal defect of the ostium secundum type. The index case and her mother also had prolonged atrioventricular conduction. It is considered that the defect is the familial type and inherited as a mendelian dominant trait. PMID- 9363670 TI - An unusual complication in releasing the detachable PDA coll. PMID- 9363671 TI - Action for health systems research in Bangladesh. PMID- 9363672 TI - Correlation of anthropometric measurements of mothers and their newborns. AB - This cross-sectional study was designed to assess the influence of the nutritional status of the mother upon the anthropometric measures of their babies. It was conducted at three different hospitals of Dhaka city during a short period of 5 weeks in 1992. One hundred and fifty mothers with their newborns were studied to correlate their anthropometric measurements. Weight, height/length and mid-arm-circumference were measured. The study showed that the correlation between weight of mother and weight of her newborn was stronger than that between heights (length) and mid-arm-circumferences of the mothers and the newborn. Correlation between mid-arm-circumference of mother and newborn was statistically insignificant whereas correlations of other variables were statistically significant. Height of mother and length of newborn daughter were less well correlated than height of mother and length of newborn son which showed relatively significant correlation (p < 0.05). The study indicates that the anthropometric measures of the newborn babies might be an outcome of the nutritional status of the mother. PMID- 9363673 TI - Etiology and clinical profile of hepatocellular carcinoma in Bangladesh. AB - Sixty-four consecutive subjects with hepatocellular carcinoma were prospectively studied in the department of Hepatology, IPGMR, Dhaka. Their mean age was 50.11 years. Fifty-two were male and 12 female. Cirrhosis was present in 12 (18.75%) subjects. Thirty subjects (46.88%) had HBsAg in their sera. Seven (58.33% of females) patients gave history of use of oral contraceptives. Cirrhosis, HBV infection, male sex, middle age, and probably the use of oral contraceptives in females appeared to be important risk factors for development of HCC in Bangladesh. Majority of patients presented with upper abdominal pain, weight loss and anorexia. Hepatomegaly was invariably present. Alpha fetoprotein was significantly higher in cirrhotic HCC patients than in non-cirrhotic ones. Median survival was two months. None of the clinical or laboratory features predicted the prognosis. PMID- 9363674 TI - IgA nephropathy in teaching hospitals of Dhaka. AB - A light and immunofluorescence microscopic study on renal biopsies were performed on 42 patients. Nephrotic syndrome with accompanying microhematuria and recurrent hematuria (Macroscopic/microscopic) with or without renal failure were the commonest indications for renal biopsy. Primary IgA nephropathy was diagnosed in five cases. Among the IgA nephropathy patients, the commonest light microscopic finding was mesangial proliferative glomerulonephritis. Macroscopic hematuria with proteinuria was the commonest feature. Three of the patients had hypertension at the time of renal biopsy. The age of the patients ranged from 19 38 years with a mean of 26 years. The high frequency of hypertension, degree of proteinuria and associated renal failure in one patient that it is a progressive disease. This preliminary study revealed that IgA nephropathy exists in Bangladesh. Larger samples need to be studied with a view to find out its prevalence and its peculiarities in this part of the world. PMID- 9363675 TI - Lung function parameters of Bangladeshi male subjects in different living conditions. AB - The "standard" values of pulmonary function tests obtained from Western populations do not agree with that of people of Bangladesh. The present survey was conducted with a view to determining the values of three lung functions parameters, viz., vital capacity, forced vital capacity, and forced expiratory volume in healthy Bangladeshi male population. 250 non-smoker male subjects of age 20-40 years were selected for the study. Of these 150 were university students and employees and 100 were low income group slum dwellers. All three values correlated positively with height and weight and negatively with age. There was a definite effect of aging on the lung function showing a declining trend from age 35 years onwards. The slum dwellers showed lower values (-12.5% in young adults) of lung functions than the university students and employees. The difference decreased with age. Prediction equations were set up using height, weight, and age as parameters. In general the lung function values were found to be 80% of the European Standards. PMID- 9363676 TI - Epidemiological study of endemic cretinism in a hyperendemic area. AB - A cross sectional survey was carried out to detect prevalence of cretinism in two rural areas of Bangladesh (one hyperendemic and the other non-endemic area). The size of the study population was four thousand five hundred and nine, the age ranged from 2 to 45 years. The prevalence of cretinism was 0.6% in the hyperendemic area, while there were no case of cretinism in the non-endemic zone. Of the 27 cretins, 18 (67%) were of the neurological type and 9 (33%) of mixed type. Males were more likely to be affected than females (p < 0.05). Cretinism was more prevalent in the 2-9 years age group. The hyperendemic area was deficient of iodine in food and the cretins were underweight. These observations call for a need for coordinated public health actions to control this serious problem. PMID- 9363677 TI - p57KIP2 targeted disruption and Beckwith-Wiedemann syndrome: is the inhibitor just a contributor? AB - Beckwith-Wiedemann syndrome is a human congenital disorder characterized by a wide variety of growth abnormalities, including developmental defects and predisposition to certain tumors. Genetic evidence has suggested a role for p57KIP2, a member of a family of cell cycle inhibitory genes, in Beckwith Wiedemann syndrome. Two independent groups have reported the generation and characterization of mice lacking functional p57KIP2. These mice demonstrate a number of abnormal phenotypes which overlap with, although do not completely recapitulate, Beckwith-Wiedemann syndrome. These findings advance the molecular characterization of a human disorder, and provide insight into the interplay between regulation of cell division and development. PMID- 9363678 TI - Ion channel targeting in neurons. AB - Electrical signaling by neurons depends on the precisely ordered distribution of a wide variety of ion channels on the neuronal surface. The mechanisms underlying the targeting of particular classes of ion channels to specific subcellular sites are poorly understood. Recent studies have identified a new class of protein protein interaction mediated by PDZ domains, protein binding modules that recognize specific sequences at the C terminus of membrane proteins. The PDZ domains of a family of synaptic cytoskeleton-associated proteins, typified by PSD 95, bind to the intracellular C-terminal tails of NMDA receptors and Shaker-type K+ channels. This interaction appears to be important in the clustering and localization of these ion channels at synaptic sites. Recognition of specific C terminal peptide sequences by different PDZ domain-containing proteins may be a general mechanism for differential targeting of proteins to a variety of subcellular locations. PMID- 9363679 TI - Vertebrate head induction by anterior primitive endoderm. AB - In vertebrates the antero-posterior organization of the embryonic body axis is thought to result from the activity of two separate centers, the head organizer and the trunk organizer, as operationally defined by Spemann in the 1920s. Current molecular studies have supported the existence of a trunk organizer activity while the presence of a distinct head inducing center has remained elusive. Mainly based on analyses of headless mutants in mice, it has been proposed that the anterior axial mesoderm plays a determining role in head induction. Recent gain- and loss-of-function studies in various organisms, however, provide compelling evidence that a largely ignored region, the anterior primitive endoderm, specifies rostral identity. In this review we discuss the emerging concept that the anterior primitive endoderm, rather than the prechordal plate mesoderm, induces head development in the vertebrate embryo. PMID- 9363680 TI - Molecular events in neutrophil transepithelial migration. AB - Neutrophil transepithelial migration is a central component of many inflammatory diseases of the gastrointestinal, respiratory and urinary tracts, and correlates with disease symptoms. In vitro modeling with polarized intestinal epithelial monolayers has shown that neutrophil transepithelial migration can influence crucial epithelial functions, ranging from barrier maintenance to electrolyte secretion. Studies have also demonstrated a dynamic involvement of the epithelium in modulating neutrophil transepithelial migration. Characterization of the molecular interactions between neutrophils and epithelial cells has revealed that transepithelial migration is dependent on the neutrophil beta 2 integrin CD11b/CD18, and does not appear to involve adhesive interactions with the selectins or intercellular adhesion molecule-1. Recent studies have implicated another transmembrane glycoprotein, CD47, as a crucial component of the transepithelial migration response. While the precise function of CD47 is not known, current evidence suggests that CD47-dependent events occur after CD11b/CD18-mediated neutrophil adhesion to the epithelium. This review will highlight key features of the current understanding of the molecular events important in neutrophil migration across epithelial surfaces. PMID- 9363681 TI - Growth and development of the mammalian oocyte. AB - The oocyte is not only the rarest and the largest cell in the body, but it also has one of the most remarkable life histories. Formed in the fetal ovary and suspended at diplotene of meiosis, it may wait for years before beginning to grow, and not until this process is complete can it resume meiosis and undergo fertilisation. Major changes in the number, morphology and distribution of cytoplasmic organelles occur during growth, and a molecular program for embryogenesis is formed. Specific yolk proteins are absent and much of the RNA and some of the protein are degraded by the cleavage stage. The zona pellucida has been intensively studied, but knowledge of oocyte-specific genes is otherwise surprisingly patchy given the significance of this cell type and the expansion of reproductive technology. Finally, it is now clear that oocytes are not mere passengers which depend on granulosa cells for nutrition and regulation but actively promote the growth and differentiation of their follicles. PMID- 9363682 TI - Tyrosine phosphorylation and cadherin/catenin function. AB - Cadherin-mediated cell-cell adhesion is perturbed in protein tyrosine kinase (PTK)-transformed cells. While cadherins themselves appear to be poor PTK substrates, their cytoplasmic binding partners, the Arm catenins, are excellent PTK substrates and therefore good candidates for mediating PTK-induced changes in cadherin behavior. These proteins, p120ctn, beta-catenin and plakoglobin, bind to the cytoplasmic region of classical cadherins and function to modulate adhesion and/or bridge cadherins to the actin cytoskeleton. In addition, as demonstrated recently for beta-catenin, these proteins also have crucial signaling roles that may or may not be related to their effects on cell-cell adhesion. Tyrosine phosphorylation of cadherin complexes is well documented and widely believed to modulate cell adhesiveness. The data to date, however, is largely correlative and the mechanism of action remains unresolved. In this review, we discuss the current literature and suggest models whereby tyrosine phosphorylation of Arm catenins contribute to regulation or perturbation of cadherin function. PMID- 9363683 TI - Mammalian DNA ligases. AB - DNA joining enzymes play an essential role in the maintenance of genomic integrity and stability. Three mammalian genes encoding DNA ligases, LIG1, LIG3 and LIG4, have been identified. Since DNA ligase II appears to be derived from DNA ligase III by a proteolytic mechanism, the three LIG genes can account for the four biochemically distinct DNA ligase activities, DNA ligases I, II, III and IV, that have been purified from mammalian cell extracts. It is probable that the specific cellular roles of these enzymes are determined by the proteins with which they interact. The specific involvement of DNA ligase I in DNA replication is mediated by the non-catalytic amino-terminal domain of this enzyme. Furthermore, DNA ligase I participates in DNA base excision repair as a component of a multiprotein complex. Two forms of DNA ligase III are produced by an alternative splicing mechanism. The ubiqitously expressed DNA ligase III-alpha forms a complex with the DNA single-strand break repair protein XRCC1. In contrast, DNA ligase III-beta, which does not interact with XRCC1, is only expressed in male meiotic germ cells, suggesting a role for this isoform in meiotic recombination. At present, there is very little information about the cellular functions of DNA ligase IV. PMID- 9363684 TI - Multifunctional proteins suggest connections between transcriptional and post transcriptional processes. AB - Recent findings indicate that substantial cross-talk may exist between transcriptional and post-transcriptional processes. Firstly, there are suggestions that specific promoters influence the post-transcriptional fate of transcripts, pointing to communication between protein complexes assembled on DNA and nascent pre-mRNA. Secondly, an increasing number of proteins appear to be multifunctional, participating in transcriptional and post-transcriptional events. The classic example is TFIIIA, required for both the transcription of 5S rRNA genes and the packaging of 5S rRNA. TFIIIA is now joined by the Y-box proteins, which bind DNA (transcription activation and repression) and RNA (mRNA packaging). Furthermore, the tumour suppressor WT1, at first thought to be a typical transcription factor, may also be involved in splicing; conversely, hnRNP K, a bona fide pre-mRNA-binding protein, appears to be a transcription factor. Other examples of multifunctional proteins are mentioned: notably PTB, Sxl, La and PU.1. It is now reasonable to assert that some proteins, which were first identified as transcription factors, could just as easily have been identified as splicing factors, hnRNP, mRNP proteins and vice versa. It is no longer appropriate to view gene expression as a series of compartmentalised processes; instead, multifunctional proteins are likely to co-ordinate different steps of gene expression. PMID- 9363685 TI - Ataxia-telangiectasia: is ATM a sensor of oxidative damage and stress? AB - Ataxia-telangiectasia (A-T) is a pleiotropic recessive disorder characterized by cerebellar ataxia, immunodeficiency, specific developmental defects, profound predisposition to cancer and acute radiosensitivity. Functional inactivation of a single gene product, ATM, accounts for this compound phenotype. We suggest that ATM acts as a sensor of reactive oxygen species and/or oxidative damage of cellular macromolecules, including DNA. In turn, ATM induces signalling through multiple pathways, thereby coordinating acute phase stress responses with cell cycle checkpoint control and repair of oxidative damage. Absence of ATM is proposed to limit the repair of insidious oxidative damage that can occur under normal physiological conditions, ultimately leading to apoptosis of particularly sensitive cells, such as neurons and thymocytes. PMID- 9363687 TI - Meiotin-1: the meiosis readiness factor? AB - Meiotin-1 is a protein found in developing microsporocytes of Lilium longiflorum, and immunological assays indicate that cognates exist in both mono- and dicotyledonous plants. Its temporal and spatial expression pattern, coupled with its unusual distribution in chromatin and the properties it shares with histone H1, encourages speculation that it is involved in regulating meiotic chromatin structure. Molecular analyses provide support for the hypothesis that meiotin-1 arose from histone H1 by an exon shuffling mechanism, as meiotin-1 is an H1-like protein that lacks the amino-terminal domain shared by H1 molecules. We have proposed that meiotin-1 serves to limit chromatin condensation in order to foster the unique cytological and molecular events which occur during meiotic prophase. As such, meiotin-1 fits the role of a 'meiosis readiness factor', and its accumulation to a threshold level may commit mitotically dividing progenitor cells to differentiate into meiocytes. PMID- 9363686 TI - L-selectin: a novel receptor for lipopolysaccharide and its potential role in bacterial sepsis. AB - The activation of leukocytes by bacterial cell wall lipopolysaccharide (LPS) contributes to the pathogenesis of septic shock. It is well established that, in the presence of plasma LPS-binding protein (LBP), LPS binds with high affinity to CD14. The binding of LPS to CD14 has been associated with the activation of cells, although available evidence indicates that CD14 itself does not transduce intracellular signalling. The physiological function of this interaction is to promote host defense mechanisms of cells to combat the infection and clear LPS from the circulation. At higher concentrations of LPS, however, the activation of cells can take place in the absence of LBP and CD14, presumably through a distinct low-affinity signalling LPS receptor. On the evidence published by us and others, we propose that in neutrophils, and possibly other leukocytes, L selectin can act as a low-affinity LPS receptor. PMID- 9363688 TI - Epigenetics. PMID- 9363689 TI - On the origin of headaches. AB - Headache is one of the most common types of pain, but its causes remain poorly understood. The long-standing idea that some headaches, particularly migraine, might be caused by cerebral or cranial vasodilation has failed to find support in recent studies. Alternative hypotheses have focused on other processes that might be capable of activating or sensitizing sensory nerve fibres that innervate the blood vessels of the intracranial meninges. PMID- 9363690 TI - The evolution of insect societies. AB - The organization and evolution of insect societies has amazed natural historians since Aristotle. Charles Darwin considered social insects to be a major difficulty for his theory of evolution by natural selection because they demonstrate a rich diversity of adaptation among sterile workers leading to a complex division of labour, something that should not occur if variation in individual reproductive success is the grist for the mill of natural selection. This article shows how division of labour can self-organize from groups of cohabiting individuals without the necessity of a past history of natural selection for co-operative behaviour. It then explores how more complex social systems may evolve. PMID- 9363691 TI - Payments to gamete donors: position of the human fertilisation and embryology authority. PMID- 9363692 TI - The internal coherence of donor insemination practice: attracting the right type of donor without paying. PMID- 9363693 TI - Reproductive prohibition: restricting donor payment will lead to medical tourism. PMID- 9363694 TI - Payment or altruism? The motivation behind gamete donation. PMID- 9363695 TI - Clinical research evidence and clinical practice. AB - An informal survey among colleagues turns up the far-from surprising information that the average patient contact involves at least three or four judgements and decisions: judgements about aetiology and prognosis, decisions about diagnosis and therapy, and sometimes discussions about costs and side-effects. And so it goes: 20 patients a day, 60 decisions; 100 patients a week, 300 decisions. Who makes these decisions, the doctor or the patient? What factors govern the final choice in each case? Evidence-based medicine (EBM) is the factor getting a lot of attention these days, but clinical decisions depend on many different elements. Good doctors have always made use of experience and judgement as well as the best available evidence. PMID- 9363696 TI - Risk of endometrial cancer in relation to use of combined oral contraceptives. A practitioner's guide to meta-analysis. PMID- 9363697 TI - The effectiveness of ovulation induction and intrauterine insemination in the treatment of persistent infertility: a meta-analysis. AB - A systematic review was conducted to evaluate the effectiveness of intrauterine insemination (IUI) with or without ovarian stimulation using gonadotrophin in the treatment of persistent infertility. Relevant randomized controlled trials were identified by a diverse strategy including a hand search of 43 core journals from 1966 to the present. Two approaches to meta-analysis were used to summarize data. First, using a standard Mantel-Haenszel approach, eight trials comparing FSH/IUI with FSH/timed intercourse for unexplained infertility were combined. The common odds ratio for pregnancy was 2.37 [95% confidence interval (CI), 1.43, 3.90], suggesting a significant improvement with IUI following ovulation induction in this patient group. Although the data were statistically homogeneous, clinically important heterogeneity was present. Second, across all diagnostic groups, the independent effects of treatment with follicle stimulating hormone (FSH), clomiphene citrate, IUI, as well as the diagnoses of male factor and endometriosis were assessed using stepwise logistic regression. Based on 5214 cycles reported in 22 trials, the odds ratio for pregnancy associated with FSH use was 2.35 (95% CI, 1.87, 2.94) for IUI, 2.82 (95% CI, 2.18, 3.66) for male factor, 0.48 (95% CI, 0.37, 0.61), and for endometriosis 0.45 (95% CI, 0.27, 0.76). This summary of the best available evidence may prove useful in counselling couples who are considering FSH and/or IUI therapy. PMID- 9363698 TI - Assessment of embryonic anatomy at 6-8 weeks of gestation by intrauterine and transvaginal sonography. AB - Our purpose was to compare the ultrasound visualization of the early first trimester embryo using transvaginal and intrauterine sonography. In all, 32 women about to undergo therapeutic abortion at 6-8.9 weeks gestation were studied using a specially developed catheter-based, high-resolution, real-time miniature (2.4 mm outer diameter) ultrasonography transducer (20 MHz). Before the intrauterine sonographic procedure was performed, transvaginal sonographic assessment of the embryo was conducted. The parameters evaluated included the ability to visualize anatomical structures and a subjective assessment of the overall image clarity. The ability to view most organs was better with intrauterine sonography compared to transvaginal sonography, and this was especially true for the brain, spine, heart, liver, midgut herniation, extremities, and sacral tail. Moreover, it was possible to obtain finer image quality of very small embryonic structures with intrauterine sonography than with transvaginal sonography. Stomach, spleen, kidney, and bladder could not be depicted with both techniques. One cystic hygroma was diagnosed at 7 weeks 6 days using intrauterine sonography, but not with transvaginal sonography. Intrauterine sonography may provide additional information on the visualization of anatomical structures of the embryo in the early first trimester of pregnancy. In this limited series, one case of cystic hygroma was demonstrated and, thus, there is a potential for its use in the early detection of embryonic malformation. These results suggest that intrauterine sonography may be a valuable tool in imaging the early first-trimester embryo, complementing and not replacing transvaginal sonography in high-risk pregnancies. PMID- 9363699 TI - Initiation of periovulatory events in gonadotrophin-stimulated macaques with varying doses of recombinant human chorionic gonadotrophin. AB - During in-vitro fertilization (IVF) cycles, a large bolus of human chorionic gonadotrophin (HCG) is used to induce periovulatory events, but the efficacy of lower doses is undefined. Following follicular stimulation in rhesus monkeys, oocyte nuclear maturation, IVF, granulosa cell luteinization and corpus luteum function were compared after injection of 100, 300 or 1000 IU recombinant HCG or 1000 IU urinary HCG. Bioactive HCG rose to peak concentrations within 2 h that were proportional to the dose administered (100 < 300 < 1000 IU, recombinant HCG = urinary HCG). The duration of surge values (>100 ng/ml) was also dose-dependent (0 h, 100 IU; 24 h, 300 IU; >48 h, 1000 IU, recombinant and urinary HCG). While the proportions of oocytes resuming meiosis and undergoing IVF were similar among groups, fewer animals yielded fertilizable oocytes following 100 and 300 IU (five of nine) compared to 1000 IU recombinant and urinary HCG (nine of 10). Peak values of serum progesterone in the luteal phase were similar, but declined 2 days earlier after 100 and 300 IU relative to 1000 IU recombinant and urinary HCG. Thus, 3-10 fold lower doses of HCG elicit low amplitude surges of short duration that induce periovulatory events such as re-initiation of oocyte meiosis and granulosa cell luteinization. However, oocyte fertilization and luteal function may optimally require surges of higher amplitude and longer duration similar to those produced by standard doses of 1000 IU recombinant or urinary HCG. PMID- 9363700 TI - Improved oocyte quality is obtained with follicle stimulating hormone alone than with follicle stimulating hormone/human menopausal gonadotrophin combination. AB - The aim of this study was to compare the efficacy of pure follicle stimulating hormone (FSH) with that of FSH/human menopausal gonadotrophin (HMG) combination in downregulated cycles. A total of 357 patients was evaluated retrospectively. Sixty percent of patients in the FSH group and 55% in the FSH/HMG group were new; the others were repeat patients. Ovulation was suppressed with leuprolide acetate in all patients, followed by either FSH (n = 218) or FSH/HMG (n = 119). There was no difference in patients' age, infertility factors, number of ampoules used, length of stimulation, oestradiol levels on day of human chorionic gonadotrophin (HCG) administration, number of oocytes recovered or the number of embryos transferred. Also, nuclear maturity at aspiration and fertilization rates were not different between the two groups. FSH stimulation resulted in a significantly higher percentage of mature oocytes that showed the typical 'mature' morphological characteristics (P < 0.0001). The clinical pregnancy rates per transfer were 40 and 28% in patients stimulated with pure FSH and FSH/HMG respectively (P < 0.05). The significantly higher number of immature oocytes matured in vitro in the FSH/HMG group (P = 0.001) suggests a possible effect on in-vitro maturation, due to luteinizing hormone present in HMG. The difference in mature oocyte quality may be an important determinant in the higher pregnancy rates for the FSH-stimulated patients. PMID- 9363701 TI - Further evidence of increased aromatase activity in granulosa luteal cells from polycystic ovary. AB - This study evaluated the effect of atamestane (a competitive inhibitor of P-450 aromatase) on granulosa luteal cells from polycystic and normal ovaries. Treatment with atamestane (10 micromol/l) determined a strong inhibition of basal aromatase activity in both types of cells; however, its effect was markedly more pronounced in granulosa cells from normal ovary than in granulosa cells from polycystic ovaries (PCO; P < 0.01). Concomitant treatment with insulin (25 microg/ml) and increasing doses of atamestane (0.01-10 micromol/l) caused a dose dependent inhibition of insulin-stimulated aromatase activity, but again with marked differences between the two types of cells. In granulosa cells from PCO, the minimal effective dose of atamestane was 1 micromol/l and it had an EC50 of 2.23 +/- 0.4 micromol/l and a maximal inhibitory effect of 75%; in granulosa cells from normal ovary, the minimal effective dose of atamestane was 0.01 micromol/l, the EC50 was 0.4 +/- 0.07 micromol/l, and the maximal inhibitory effect was 94%. Significant differences were observed between the different cells at all the studied dose points. Reversibility studies showed that resumption of aromatase activity in granulosa cells from PCO is basally greater and more inducible with insulin treatment. This study provides further evidence of an increased in-vitro function of the aromatase complex in granulosa cells from PCO, that could be induced by an altered cellular autoregulation. PMID- 9363702 TI - Heterogeneity in beta cell activity, hepatic insulin clearance and peripheral insulin sensitivity in women with polycystic ovary syndrome. AB - The aim of this study was to evaluate the impact of reduced peripheral insulin sensitivity, beta cell hypersecretion and reduced hepatic insulin clearance in the hyper-insulinaemia of lean and obese PCOS patients. A total of 35 women with polycystic ovary syndrome (PCOS) and 10 lean normo-ovulatory controls underwent an oral glucose tolerance test and an euglycaemic-hyper-insulinaemic clamp study. PCOS patients were classified into four groups according to their BMI and insulin secretion (normo-lean; normo-obese; hyper-lean; hyper-obese), and results were compared between groups and with the controls. All the PCOS groups showed significantly higher insulin secretion than controls; there were no differences in insulin response to glucose load between lean and obese normo- and hyper insulinaemic patients. Secretion of c-peptide was greater in PCOS groups than controls. All the hyper-insulinaemic PCOS patients had lower values of hepatic insulin clearance, independent of BMI, when compared either with controls (P < 0.001) or with PCOS normo-insulinaemic women (P < 0.01). Normo- and hyper insulinaemic obese patients had similar total body glucose utilization (M value), which was lower than in lean PCOS subjects and controls. Our results suggest that evaluation of insulin resistance alone does not fully characterize the PCOS population; differences in liver metabolism of insulin are present in obese insulin resistant subjects and in lean patients with normal insulin sensitivity when divided into normo- and hyper-insulinaemic subgroups. Insulin resistance and hyper-insulinaemia may represent two distinct features of the insulin disorder in PCOS: the former appear to reflect the presence of obesity, while the latter may be a primary feature of PCOS. PMID- 9363703 TI - Stimulation of cyclic AMP, 17beta-oestradiol and protein synthesis by human chorionic gonadotrophin in human endometrial cells. AB - Human endometrial tissue was collected from 30-37 year old ovulatory women and enzymatically dispersed and processed to obtain endometrial stromal cells. Cells (2 x 10(4)/well) were incubated in vitro in the absence (control) or presence of human chorionic gonadotrophin (HCG) (10 IU/well) either for 1 h (to determine cAMP) or for 4 h (to estimate protein synthesis, 17beta-oestradiol and aromatase activity). HCG significantly stimulated cellular cAMP content and release in comparison to control. Both cellular accumulation and release of cAMP reached the peak at 10 min and then sharply declined in the absence of phosphodiesterase (PDE) inhibitor or remained steady for 1 h in the presence of PDE inhibitor. Content and release of 17beta-oestradiol from stromal cells steeply increased from 30 min to 1 h and then slowly increased for 4 h in response to HCG. Incubation of cells with HCG significantly stimulated (P < 0.01) cellular aromatase activity in comparison to control. HCG stimulated protein synthesis of the cells in two phases, initially at 15 min which remained steady for 1 h and then significantly increased (P < 0.01) between 1 and 2 h. The initial phase of protein synthesis appears to be the direct effect of HCG while the later phase was due to the higher concentration of oestradiol caused by HCG. The initial phase of protein synthesis was inhibited by cycloheximide but not by actinomycin D, whereas the later phase of protein synthesis was inhibited both by cycloheximide and actinomycin D. Results therefore indicate a probable mechanism of HCG action on stromal cells and demonstrate the physiological relevance of gonadotrophin receptor in human endometrial cells reported earlier from this laboratory. PMID- 9363704 TI - Relevance of genetic counselling in couples prior to intracytoplasmic sperm injection. AB - Since the first reports of successful pregnancies after treatment with intracytoplasmic sperm injection (ICSI) in humans numerous attempts have been made to assess the genetic risks of this highly invasive technique. During the study period (February 1995-November 96), 142 couples were referred to our genetic counselling unit prior to ICSI. In three couples, genetic counselling revealed a high recurrence risk for a monogenic disease (myotonic dystrophy, hereditary ataxia and polycystic kidney disease). In nine out of 128 men (7%) an abnormal karyotype was identified, including three Robertsonian translocations, two reciprocal translocations, three sex chromosome aberrations and one case with centric fission of chromosome no. 7. A total of 14 men refused chromosomal analysis. Only one of the 122 women examined had an abnormal karyotype (47, XXX). Five out of six men with congenital bilateral absence of the vas deferens (CBAVD) had at least one mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Three had mutations in both CFTR alleles, including one case in which the second mutation was the 5T allele. One patient with CBAVD and a single Delta F508 CFTR mutation also had left renal agenesis. In conclusion, we strongly recommend that genetic counselling, chromosomal analysis and, in the case of CBAVD, screening for CFTR mutations should be offered to all couples with a diagnosis of male or idiopathic infertility. PMID- 9363705 TI - Intracytoplasmic sperm injection pregnancy with fetal trisomy 9p resulting from a balanced paternal translocation. AB - Infertile men who carry a chromosomal translocation can be successfully treated with intracytoplasmic sperm injection (ICSI). However, such treatment carries a risk that a pregnancy with an abnormal karyotype will be induced. While in all previously published cases the outcome was favourable, we here report the first instance of a parental reciprocal translocation leading to a chromosomally unbalanced ICSI pregnancy. The fetus, one of a pair of dizygotic twins, was found to have trisomy for the short arm of chromosome 9. The parents opted for selective abortion of the affected twin. PMID- 9363706 TI - Induction of messenger RNA for the 70 kDa heat shock protein in HeLa cells and the human endocervix following exposure to semen: implications for antisperm antibody production and susceptibility to sexually transmitted infections. AB - The 70 kDa heat shock protein (HSP70) is induced in cells exposed to chemical or physical stress. HSP70 facilitates cell survival by preventing protein denaturation and incorrect assembly of polypeptides. Induction of HSP70 messenger RNA (mRNA) synthesis also inhibits transcription of genes coding for pro inflammatory cytokines. We analyzed whether HSP70 mRNA was expressed in a cultured human cervical cell line (HeLa cells) following exposure to human semen, or in cells obtained from the endocervices of sexually active women. HeLa cells were co-cultured with a 1:50 dilution of semen from four men, with purified spermatozoa, or with cell-free seminal fluid. Endocervical swabs were obtained at mid-cycle from 53 women. HSP70 mRNA was detected in HeLa cells by a reverse transcriptase-polymerase chain reaction (RT-PCR) and analysis on agarose gels. HSP70 mRNA in cervical cells was measured by RT-PCR followed by hybridization with an HSP70-specific internal probe and detection by ELISA. Cervical IgA antibodies to HSP70 were measured by ELISA. HeLa cell-semen co-culture led in each case to induction of HSP70 mRNA. Cell-free seminal fluid and isolated motile spermatozoa also induced HSP70 mRNA when incubated individually with HeLa cells. HSP70 mRNA was detected in 28 (52.8%) of 53 endocervical cell samples obtained from women at varying times after sexual intercourse. The percentage of samples expressing HSP70 mRNA was 37.5% at <10 h, 64.3% at 10 h, 70.0% at 11 h and between 36 and 50% at later times after semen exposure. Cervical IgA antibodies to HSP70 were also detected in some women and their occurrence was highly correlated with HSP70 gene transcription (P < 0.0001). The data demonstrate that exposure to semen induces HSP70 mRNA in endocervical cells. PMID- 9363707 TI - Efficiency of sex pre-selection of spermatozoa by albumin separation method evaluated by double-labelled fluorescence in-situ hybridization. AB - To evaluate the separation efficiency of Ericsson's two- and three-layer albumin separation methods, semen samples from 21 healthy males were studied. Seven patients already had two or more sons, another seven had two or more daughters and the other seven had primary infertility due to female factors. The semen samples were divided into three aliquots: one remained unprocessed initially, the other two aliquots went through two- and three-layer albumin separation methods respectively. All samples were then stained with X-Y double staining probes. In each group, four or five samples were processed at room temperature, and two or three at body temperature (37 degrees C). The labelling efficiency of X-Y double staining probe was over 99%. The X:Y sperm ratios were even in the original samples. The ratios of the X and Y spermatozoa were altered slightly but significantly after the two-layer (P < or = 0.05) or the three-layer (P < or = 0.005) separation. The alterations occurred only at room temperature. The X spermatozoa increased and the Y spermatozoa decreased, both to a small degree of difference (1.4-3.5%). Double fluorescence in-situ hybridization analysis therefore showed that albumin separation methods do not enrich Y spermatozoa. PMID- 9363708 TI - Laparoscopic myomectomy: indications, surgical technique and complications. AB - The indications and complications of laparoscopic myomectomy were evaluated with regard to its limitations, benefits and feasibility. Surgical technique with related difficulty was also reported. From a population of 89 patients, a total of 104 myomas were removed laparoscopically. A retrospective study was carried out of 54 patients with myomas >3 cm. Indications for surgery were pain or abnormal bleeding (37%), increase in size of the myoma in infertile patients (48.1%) and infertility requiring assisted reproductive technology (14.9%). A total of 57 myomas >3 cm were removed from these patients. The number of myomas per patient varied from 1 to 4. The myomas were intramural (n = 34), subserosal (n = 19) and submucosal (n = 4). The size of the dominant myoma ranged from 3-8 cm (mean 4.16). In all cases the uterine wall was sutured either in one (n = 42) or two planes (n = 15) depending on the depth of the myometrial defect. The laparotomy conversion rate was 1.8% (n = 1); mean blood loss was 84 ml; average hospital stay was 2.09 days and the overall complication rate was 1.8%. Five patients went on to conceive; the pregnancy was uneventful and proceeded to Caesarean section at 38 weeks. No adhesions at myomectomy sites were observed in these patients. At 6 months follow-up, 18 out of 20 patients with pain or haemorrhagic disorders prior to surgery showed remission of their complaints. Our study confirms the feasibility of laparoscopic myomectomy as a technique leading to a low complication rate and remission of symptoms. At the present time, statistically significant data concerning post-surgical adhesion formation or pregnancy outcome are not available. PMID- 9363709 TI - Fertility after laparoscopic myomectomy: preliminary results. AB - We report the limits, complications, subsequent fertility and outcome of pregnancies after laparoscopic myomectomy. From January 1990 to October 1995, 143 patients underwent a first laparoscopic approach to myomectomy. A total of 41 patients (28.7%) had a laparoconversion (12 cases for a number of myomata >5, 15 cases for myoma diameter >7 cm, 12 cases for peroperative haemorrhage and two cases for adenomyosis). Seventy patients (49%) wished to conceive: 26 had undergone laparoconversion and 44 laparoscopic myomectomy. A total of 19 pregnancies were obtained in 17 patients after laparoscopic myomectomy (38.6%): eight vaginal deliveries, three Caesarean sections, four miscarriages, two abortions, one ectopic pregnancy and one therapeutic abortion. The pregnancy rate in patients with unexplained infertility and with multifactorial infertility was 48.2% and 20% respectively. The mean delay to conception was 11.3 months. No uterine rupture was noted. Pelvic adhesions were found in the four patients who underwent second-look procedure. Our preliminary results indicate that laparoscopic myomectomy is a useful technique. PMID- 9363710 TI - Postoperative adhesion formation and reproductive outcome using Interceed after ovarian surgery: a randomized trial in the rabbit model. AB - The efficacy of an oxidized regenerated cellulose barrier (Interceed) in reducing postoperative adhesion formation and improving reproductive outcome after ovarian surgery was evaluated in a prospective randomized trial. Twenty-nine New Zealand White female rabbits were submitted to a mid-line laparotomy and a standardized surgical incision was made on both ovaries. At random, one ovary was entirely wrapped in a sheet of Interceed, whereas the contralateral ovary was left uncovered. Four weeks following surgery, the rabbits were mated with a male of proven fertility. Two weeks later, a second-look laparotomy was performed by a blinded observer who evaluated the incidence and score of adhesions, the number of corpora lutea in each ovary, the number of embryos in the ipsilateral uterine horn and also calculated the nidation index for each side. Adhesions were observed in 66% of Interceed-covered and in 97% of control ovaries (P < 0.0001). The adhesion score on the Interceed side was significantly lower than on the control side. The nidation index for the Interceed side was significantly higher than for the control side. The authors conclude that, in the rabbit model, Interceed significantly reduces the incidence and score of postoperative ovarian adhesions and significantly improves reproductive outcome. PMID- 9363711 TI - Cumulative pregnancy rates in couples with anovulatory infertility compared with unexplained infertility in an ovulation induction programme. AB - Using a retrospective analysis, we compared cumulative pregnancy rates, early pregnancy failure rates and multiple pregnancy rates in couples with polycystic ovarian syndrome (PCOS) (n = 148), hypogonadotrophic or eugonadotrophic hypogonadism (n = 91) and unexplained infertility (n = 117), who were treated in an ovulation induction clinic between January 1991 and December 1995. The women were treated with either human menopausal gonadotrophin (HMG) or purified follicle stimulating hormone (FSH). The cumulative pregnancy rate (derived from life-table analysis) after four ovulatory treatment cycles was 70% in the PCOS group, 74% in the hypogonadism group and 38% in the unexplained infertility group. The cumulative pregnancy rate in the unexplained infertility group was significantly lower than the other groups (P < 0.001) but there was no significant difference between PCOS and hypogonadism using the log rank test. The early pregnancy failure rate was 25% in the PCOS group, 27% in the hypogonadism group and 26% in the unexplained infertility group (chi(2) = 0.132, not significant). The multiple pregnancy rate was 20% in the PCOS group, 30% in the hypogonadism group and 17% in the unexplained infertility group (chi(2) = 2.105, not significant). Treatment of anovulatory infertility using HMG or FSH is effective irrespective of the cause. Couples with unexplained infertility are less successfully treated using HMG: correction of unexplained infertility may involve more than simple correction of possible subtle ovulatory defects. PMID- 9363712 TI - A prospective, randomized, cross-over comparison of two methods of artificial insemination by donor on the incidence of conception: intracervical insemination by straw versus cervical cap. AB - In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina. PMID- 9363713 TI - Hyaluronic acid substantially increases the retention of motility in cryopreserved/thawed human spermatozoa. AB - We have demonstrated previously that hyaluronic acid (HA) improves the velocity and the retention of motility in freshly ejaculated human spermatozoa. In the present work, we examined the effect of HA on cryopreserved/ thawed spermatozoa in four paradigms: (i) effect of HA on sperm motility and velocity in semen; (ii) stabilizing effect of HA after 4 h of incubation when the decline of sperm motility is already detectable; (iii) the duration of improved motility after the separation of spermatozoa from HA by Percoll gradient centrifugation; and (iv) motility of sperm cryopreserved in the presence of HA. HA improved the retention of sperm motility in thawed spermatozoa. Indeed, the motility values after 30 h were approximately 100% higher in the HA compared with the control samples. This effect of HA was also evident in the stabilization of spermatozoa with already declining motility. After removal of the HA from the incubation medium, significantly increased motility in the HA-exposed spermatozoa was still detectable for at least 4 h. Cryopreservation of spermatozoa in the presence of HA did not improve the recovery of motility. The data indicate that HA improves the retention of motility of cryopreserved/thawed spermatozoa, even after the removal of HA from the incubation medium. The utilization of HA will probably prove beneficial in assisted reproduction: in intrauterine insemination and in in vitro fertilization (IVF), the extended sperm motility and velocity will enhance the fertilizing efficiency; in intracytoplasmic sperm injection (ICSI), the improved motility will facilitate the identification of viable spermatozoa. Because HA is a physiological component of the cumulus and of the female and male reproductive tracts, administration of HA should not cause ethical concerns. PMID- 9363714 TI - The effect of follicle stimulating hormone therapy on human sperm structure (Notulae seminologicae 11). AB - The effects of follicle stimulating hormone (FSH) treatment on the quality of human spermatozoa were assessed by examining the ultrastructure and the function of infertile human spermatozoa using a previously-defined formula. Using the spermatozoa as an andrological monitor shows that the therapeutic effect of FSH depends on the type of sperm defect. The response to FSH is, in many cases, positive and can be evaluated by examining the state of the ejaculated spermatozoa. From an initial group of 81 patients, 15 were placebo-treated controls, and 19 were non-responders (mainly with microbially infected semen). Out of 47 responders, after therapy nine achieved improved sperm quality which approached the natural fertility threshold. These responders all had spermatozoa affected by immaturity or apoptosis (n = 27). The 20 microbially-infected responders also had immature spermatozoa and never achieved the quality level of natural fertility. Thus, a natural fertility level was only achieved by nine responders out of 27 (three with immature spermatozoa, and six with apoptotic spermatozoa). Using our method of sperm analysis, these patients' spermatozoa were clearly categorized before treatment as either immature or apoptotic. In consequence, the success of the therapy was predictable. The response of individual organelles to therapy was examined. Certain qualities of the acrosome, the chromatin, the mitochondria, and the axoneme appear to be sensitive to FSH. Most of the previous conflicting results reported in the literature may be due to a lack of relevant discrimination between the different defects present in the spermatozoa of the patients, without assessing the likelihood of their response. PMID- 9363715 TI - A sperm survival test and in-vitro fertilization outcome in the presence of male factor infertility. AB - Several tests based on semen variables have been proposed to predict the fertilization rate in the presence of male factor infertility, but their significance remains unclear. We investigated the utility of a screening test based on sperm survival (SST) to predict the outcome of in-vitro fertilization (IVF) cycles in the presence of male factor infertility. The SST was considered normal when the percentage of motile spermatozoa 24 h after oocyte insemination was > or =50%. The sperm survival test yielded abnormal results in <90% of cycles which were unsuccessful. The sensitivity of the SST was 87% and specificity 65% with a positive predictive value of 90% in the male factor group. We believe that the SST may be a useful predictor of the IVF cycle outcome and we propose its introduction into the routine preliminary evaluation of semen samples in cases of male factor infertility. PMID- 9363716 TI - Intracytoplasmic sperm injection in obstructive and non-obstructive azoospermia. AB - We compared the results of intracytoplasmic sperm injection (ICSI) in: (i) obstructive versus non-obstructive azoospermia, (ii) obstructive azoospermia using epididymal versus testicular spermatozoa and (iii) acquired versus congenital obstructive azoospermia due to congenital absence of the vas deferens (CAVD). A retrospective analysis was done of 241 consecutive ICSI cycles done in 103 patients with non-obstructive azoospermia and 119 patients with obstructive azoospermia. In the obstructive group, 135 ICSI cycles were performed. Epididymal spermatozoa were used in 44 cycles and testicular spermatozoa in 91 cycles. In the non-obstructive group, 106 cycles were performed. The fertilization and pregnancy per cycle rates were 59.5 and 27.3% respectively using epididymal spermatozoa, 54.4 and 31.9% respectively using testicular spermatozoa in obstructive cases, and 39 and 11.3% respectively in non-obstructive cases. The fertilization and pregnancy per cycle rates were 56.6 and 37% respectively in acquired obstructive cases, and 55.2 and 20.4% respectively in CAVD. In conclusion, ICSI using spermatozoa from patients with acquired obstructive azoospermia resulted in significantly higher fertilization and pregnancy rates as compared to CAVD and non-obstructive cases. PMID- 9363717 TI - Percoll gradient centrifugation can be omitted in sperm preparation for intracytoplasmic sperm injection. AB - Prior to intracytoplasmic sperm injection (ICSI), seminal fluid is currently washed out from the ejaculated semen and further sperm selection is carried out by a discontinuous Percoll gradient. Possible deleterious effects from the sperm separating substance Percoll on sperm function or embryo cleavage after in-vitro fertilization (IVF) have, to our knowledge, not yet been reported and the use of Percoll has been widely accepted in IVF. In this study, we examined whether the omission of the Percoll step in the sperm preparation has any influence on the outcome of the ICSI procedure. Two methods of sperm preparation for ICSI were compared in a controlled study on sibling oocytes: washing the semen sample once, followed by a Percoll gradient centrifugation versus washing the sperm sample twice without a Percoll gradient centrifugation. The mean fertilization rates were similar for the two sperm preparation methods: 78.2 +/- 21.4 and 75.0 +/- 24.1% respectively of the intact oocytes displaying two pronuclei. Cleavage rates did not differ statistically between the two groups. Whereas in both groups similar percentages of excellent, good and poor quality embryos were obtained, the percentage of fair quality embryos was significantly higher in the group without Percoll (16.3 +/- 20.1 versus 9.1 +/- 15.7%). However, no statistical differences were observed in either the percentage of transferable embryos or in the percentage of embryos actually transferred or frozen in the two groups. In conclusion, spermatozoa from ejaculates that are washed out from the seminal fluid without any further selection can be used for ICSI without any adverse effect on fertilization and embryo cleavage. PMID- 9363718 TI - Greater numbers of human spermatozoa associate with endosalpingeal cells derived from the isthmus compared with those from the ampulla. AB - A simple co-culture bioassay system was used to investigate whether or not the anatomical origin affected the ability of epithelial cells from the human uterine (Fallopian) tube to 'bind' spermatozoa. This study was also used to identify some of the factors which may be involved in the regulation of sperm-epithelial interactions in vitro by comparing different tissue culture models and assessing the effect of oestradiol concentration. Epithelial explants harvested from different regions of human uterine tubes were co-incubated with a known concentration of motile donor spermatozoa. All results were adjusted to reflect a standard sperm concentration of 5 x 10(6)/ml. More spermatozoa associated per field of isthmic compared to ampullary epithelium [isthmus 9.5 +/- 0.9, ampulla 7.1 +/- 0.7 (mean +/- SEM); n = 36, P < 0.05, ANOVA] and cells from post menopausal patients had an apparently reduced ability to bind spermatozoa [isthmus 5.5 +/- 2.0, ampulla 4.3 +/- 1.4 (mean +/- SEM); n = 4]. Neither menstrual cycle stage nor addition of mid-cycle concentrations of 17beta oestradiol (750 pmol/l) affected the number of spermatozoa which bound to epithelium from either tubal region. In addition, the number of spermatozoa which bound per field of polarized explants was greater (P < 0.05) than that bound to dissociated primary and passaged epithelial cell monolayers. This report is the first to provide evidence suggestive of a role for sperm-epithelial binding in the formation of an isthmic sperm reservoir in the human uterine tube. Results also indicate that oestrogen is not involved in the regulation of these interactions, and that cell polarity is an important factor for such associations in vitro. PMID- 9363719 TI - Initiation of growth of baboon primordial follicles in vitro. AB - Factors that cause some primordial follicles to enter the growth phase while the others remain quiescent are unknown. The hypothesis was tested that primate primordial follicles can survive and initiate growth in vitro in serum-free medium. Superficial pieces of ovarian cortex, containing mostly primordial follicles, were obtained from baboon fetuses during late gestation and cultured for 0, 2, 4, 7, 10 or 20 days in Waymouth MB 752/1 medium supplemented with insulin, transferrin, selenium, linoleic acid, and bovine serum albumin (ITS +). Histological examination of cortical pieces revealed that after 2 and 4 days in culture, the total number of primordial follicles had decreased by 55 and 76% (P < 0.01) respectively, relative to day 0 of culture. This was associated with a sustained, 5- to 8-fold increase in total primary follicles (P < 0.01) beginning on day 2 of culture. There was also a gradual increase in the total number of early secondary and secondary follicles. The average diameter of follicles and oocytes increased gradually throughout culture for all follicular categories (P < 0.01), except secondary follicles and oocytes. Immunohistochemical localization of proliferating cell nuclear antigen (PCNA), a marker for cell proliferation and growth, showed that PCNA was generally absent in primordial follicles on day 0, but was observed after 2 or 4 days in culture in both granulosa cells and oocytes of most growing follicles. Comparison of cortical pieces cultured for 10 or 20 days with ITS + versus 10% fetal bovine serum (FBS) showed a more pronounced decrease in the numbers of primordial follicles and more primary, early secondary and secondary follicles in ITS + compared to FBS-treated cortical pieces (P < 0.01 at 20 days). These results show that primordial follicles from non-human primates can survive and develop to the secondary stage in vitro in serum-free conditions. PMID- 9363720 TI - Relationship of human follicular diameter with oocyte fertilization and development after in-vitro fertilization or intracytoplasmic sperm injection. AB - The aim of this work was to evaluate the relationship between follicular size at the time of oocyte retrieval, and the subsequent oocyte competence to be fertilized and to develop in vitro. All the obtained oocytes were classified according to the corresponding volume of aspirated follicular fluid. Aspirated volume of follicular fluid <2 ml corresponded to a follicular diameter <16 mm and constituted the small size group. Volume of follicular fluid from 2 to 6 ml corresponded to a diameter from 16 to 23 mm and constituted the medium size group. The large size group contained follicles with diameter >23 mm and corresponded to an aspirated volume of follicular fluid of >6 ml. A progressive and significant increase in the rates of oocytes with a first polar body was observed from the small size group to the other groups and from the medium to the large size group: 75.3, 85.9 and 95.3% respectively. After classical in-vitro fertilization (IVF), significantly better rates of fertilization and development were obtained in the medium size group compared to the two other groups. Moreover, a positive relationship was observed between follicular diameter and rates of embryos scored as 'good' when oocytes were fertilized by intracytoplasmic sperm injection (ICSI). These results demonstrated that follicular size is positively related to the oocyte ability to be fertilized and to develop. Although oocytes from small follicles gave lower percentages of development probably due to partial oocyte incompetence, they allowed an increase in the total number of embryos scored as 'good'. PMID- 9363721 TI - Viability of partially damaged human embryos after cryopreservation. AB - In our centre, embryos are judged to have survived cryopreservation if at least half of the initial number of blastomeres remain intact. Therefore both fully intact and partially damaged embryos are transferred. The aim of this study was to investigate the viability of partially damaged human embryos after cryopreservation. We retrospectively analysed the implantation and in-vivo development of embryos which were either fully intact or had lost some blastomeres after cryopreservation. Oocytes were collected following stimulation with the gonadotrophin-releasing hormone (GnRH)-agonist Buserelin and human menopausal gonadotrophin. Supernumerary multicellular embryos with not more than 20% of their volume filled with anucleate fragments were frozen on day 2 or day 3 of the cycle using a slow cooling procedure with dimethylsulphoxide as the cryoprotectant. Following slow thawing, 431 fully intact embryos were transferred in 314 embryo transfer procedures and 488 partially damaged embryos were transferred in 327 such procedures. The percentage of gestational sacs with fetal heartbeat obtained after transfer of fully intact embryos was almost three times higher than that after transfer of partially damaged embryos (11.4 versus 3.5%). Forty-five children (birth rate 10% per embryo transfer) were born after transfer of fully intact embryos and 14 after transfer of embryos from which some blastomeres had been lost following cryopreservation. In conclusion, although children have been delivered after transfer of partially damaged embryos, the aim of a cryopreservation programme must be to obtain fully intact embryos after thawing. PMID- 9363722 TI - Analysis of unfertilized oocytes subjected to intracytoplasmic sperm injection using two rounds of fluorescence in-situ hybridization and probes to five chromosomes. AB - Chromosomal aberrations are the major cause of pre- and post-implantation embryo wastage and some studies suggest that half of all human conception have a chromosomal abnormality. Analysis of gametes provides information on the origin of these chromosomal aberrations. The purpose of this study was to develop a reliable multi-probe fluorescence in-situ hybridization (FISH) procedure that would enable us to investigate aneuploidy in unfertilized oocytes subjected to intracytoplasmic sperm injection (ICSI). Oocytes were spread with HCl and Tween 20 solution, and then two rounds of triple-probe FISH were performed on each oocyte using directly-labelled centromeric probes: chromosomes 1, 7, 15 (overnight hybridization); chromosomes 1, X, Y (2 h hybridization). After the first round, the slides were counterstained and evaluated, and the positions of FISH signals were recorded. For the second round, the counterstain was removed and the second probe cocktail was applied. The chromosome 1 probe was an internal control for the two hybridization procedures, while the Y chromosome probe was used to detect sperm DNA. To evaluate the method, a total of 79 oocytes from 27 patients were studied. Of these, 67 (84.8%) were successfully spread and 97% of these oocytes exhibited discernible FISH signals. Upon lysis, oocytes exhibited one or more DNA fragments (mean 1.9, range 1-3). Of the 65 analysable oocytes, 17 (26.2%) displayed a normal haploid chromosome constitution with paired spots for the two chromatids. A further 23 oocytes (35.4%) showed an ambiguous chromosome complement due to an abnormal number of DNA fragments which may have resulted from loss of DNA during spreading or to an abnormal oocyte, while 25 oocytes (38.4%) displayed aneuploidy for one or more of the chromosomes studied. In conclusion, this new approach is a quick and efficient method with which numerical chromosomal abnormalities in human oocytes can be studied; interpretation of the patterns of DNA fragments and FISH signals requires further clarification. PMID- 9363723 TI - Carrier-specific breakpoint-spanning DNA probes: an approach to preimplantation genetic diagnosis in interphase cells. AB - Carriers of chromosomal inversions or other balanced rearrangements represent a significant fraction of patients in in-vitro fertilization (IVF) programmes due to recurrent reproductive problems. In most cases, chromosomal imbalance in fertilized oocytes is incompatible with embryo survival leading to increased rates of spontaneous abortions. Assuming that a fraction of the germ cells is karyotypically normal, these patients would greatly benefit from efficient procedures for generation and use of breakpoint-specific DNA hybridization probes in preconception and preimplantation genetic diagnosis (PGD). We describe the generation of such patient-specific probes to discriminate between normal and aberrant chromosomes in interphase cells. First, a large insert DNA library was screened for probes that bind adjacent to the chromosomal breakpoints or span them. Then, probe and hybridization parameters were optimized using white blood cells from the carrier to increase in hybridization signal intensity and contrast. Finally, the probes were tested on target cells (typically polar bodies or blastomeres) and a decision about the colour labelling scheme was made, before the probes can be used for preconception or preimplantation genetic analysis. Thus, it was demonstrated that cells with known structural abnormalities could be detected, based on hybridization of breakpoint spanning yeast artificial chromosome (YAC) DNA probes in interphase cells. PMID- 9363724 TI - Treatment of uterine leiomyomas with luteinizing hormone-releasing hormone antagonist Cetrorelix. AB - The efficacy of the luteinizing hormone-releasing hormone antagonist Cetrorelix (SB-75) in the medical management of uterine leiomyomas (fibromas) was evaluated. Cetrorelix was administered to 18 pre-menopausal women with myomas with a mean age of 33.3 years, who had been candidates for hysterectomy. The initial dose of Cetrorelix was 5 mg twice daily s.c. for the first 2 days and thereafter 0.8 mg was given twice daily s.c. for at least 3 months. The mean duration of the treatment was 4.4 months. Before the therapy with Cetrorelix, the mean uterine volume, measured by ultrasonography, was 395.4 +/- 69.2 ml (range 89-1166). Sixteen patients showed a progressive reduction in uterine volume from 410.4 +/- 77.1 to a mean of 230.8 +/- 52.6 ml at 3 months. All patients became amenorrhoeic and had hot flushes. After treatment with Cetrorelix, a surgical myomectomy was performed in 12 women. One of the patients subjected to myomectomy after therapy with Cetrorelix became pregnant. These patients have been followed for up to 25 months and only in one case has the uterine volume increased after therapy. Three patients had good responses to therapy with Cetrorelix and it was decided to follow them only by observation. One patient became pregnant 2 months later. In the other patient, the uterine volume remained unchanged for the duration of the follow-up of 2 years and the third patient showed an increase after 21 months. In three patients, it was necessary to perform total hysterectomy. In 14 patients, serum concentrations of luteinizing hormone, follicle stimulating hormone and oestradiol decreased after the administration of the first dose of Cetrorelix and continued at subnormal values throughout therapy. In 15 patients who were not subjected to total hysterectomy, menstrual function returned at 1 month after cessation of treatment. Overall results support the use of Cetrorelix for the management of uterine leiomyomas. PMID- 9363725 TI - Endothelin and neutral endopeptidase in the endometrium of women with menorrhagia. AB - The mechanisms underlying excessive menstrual bleeding or menorrhagia are not understood. In view of its potent vasoconstrictor and growth factor properties, endothelin has been proposed to have a potential paracrine role in the regulation of uterine blood flow and therefore could be a factor in menorrhagia. We compared the cellular localization of endothelin and its metabolizing enzyme, neutral endopeptidase, in endometrial biopsies from women with documented menorrhagia and in those with a normal menstrual cycle. Menorrhagia was documented by measurement of menstrual blood loss, 146 +/- 141 ml (median +/- SD). Endothelin and neutral endopeptidase were localized by immunohistochemistry, and the staining intensity was graded. Their immunostaining patterns were found to differ in menorrhagia compared to the normal menstrual cycle. Endothelin was reduced in glandular epithelium in menorrhagia and did not vary cyclically, while neutral endopeptidase was increased in the glandular epithelium. In menorrhagia, stromal endothelin immunoreactivity was not different from the normal cycle and although neutral endopeptidase immunostaining in stroma was similar to the secretory phase of normal endometrium, cyclical variation was absent. The potential for increased metabolism of endothelin could be an explanation for the decreased endothelin immunostaining in the glandular epithelium. PMID- 9363726 TI - Endometrial assessment procedures: an audit of current practice in Scotland. AB - The objective was to determine, in relation to endometrial assessment procedures, the extent to which the current practice of gynaecologists in Scotland (as assessed both by questionnaire survey of clinicians and review of hospital records) accords with recommendations in recent evidence-based guidelines. All 132 consultant gynaecologists in Scotland were surveyed and 123 (93%) responded. In addition, the case records of 1199 consecutive women undergoing endometrial assessment procedures in 12 representative hospitals were reviewed. Over two thirds of consultants agreed that endometrial assessment procedures are seldom indicated in women aged under 40 years and over 80% agreed that when such procedures are indicated, outpatient endometrial biopsy represents the method of choice. However, the review of case records showed that 23% of the women who underwent endometrial assessment were aged under 40 years and only 44% of the procedures undertaken were out-patient endometrial biopsies. We conclude that some Scottish women may be undergoing endometrial assessment procedures unnecessarily and that, in some centres, traditional dilatation and curettage is being replaced by hysteroscopy under general anaesthetic in theatre although there is no evidence that this procedure provides more clinically useful information than out-patient endometrial biopsy. PMID- 9363727 TI - Pentoxifylline versus placebo in the treatment of infertility associated with minimal or mild endometriosis: a pilot randomized clinical trial. AB - The present study is the first prospective randomized controlled trial of the effect of pentoxifylline on future fertility in infertile women with asymptomatic minimal or mild endometriosis. After completion of a basic infertility workup and laparoscopy, patients were entered into the study and randomly allocated to receive either a 12 month course of oral pentoxifylline (800 mg/day) (n = 30) or an oral placebo (n = 30). Those patients with other infertility factors were included in the study only if the factors were correctable and ultimately determined to be non-contributory. Life-table analysis was used to compare pregnancy rates between the two groups over a 12 month period that started immediately after laparoscopy. The 12 month actuarial overall pregnancy rates were 31 and 18.5% in the pentoxifylline and placebo groups respectively. However, this difference was not statistically significant by the chi(2)-test. Similarly, the Cox regression method showed no differences between the hazard of pregnancy in the two groups studied (odds ratio, 0.56; 95% confidence interval, 0.18-1.67). Therefore, there is no evidence from this study that immunomodulation with pentoxifylline aids fertility in those women with minimal or mild endometriosis. Further studies including more infertile patients with endometriosis are desirable in order to confirm our results. PMID- 9363728 TI - Localization of fibrillin-1 in human endometrium and decidua during the menstrual cycle and pregnancy. AB - We have examined the existence and distribution of fibrillin-1 within the endometrium and decidua to ascertain the effect of decidualization upon its synthesis, and its relationship to other extracellular matrix proteins. Formalin fixed, paraffin-embedded tissues were stained using monoclonal antibodies to collagen IV, elastin, fibrillin-1 and laminin, by immunocytochemistry. Fibrillin 1 was present throughout the menstrual cycle and appeared to be cell-associated. Similar staining for fibrillin-1 was detected within the Fallopian tube of ectopic pregnancy material. In first trimester, second trimester and term decidua, staining for fibrillin-1 was more intense than that during the menstrual cycle and was detected as a thick layer encapsulating decidual cells, but also in fibrillar form inter-connecting these cells. In comparison with the association of collagen IV and laminin with all basal laminae, fibrillin-1 was absent from the vascular and glandular elements of pregnancy endometrium. Elastin was absent in all tissues examined. Hence, fibrillin-1 exists within the uterus in association with basal lamina components rather than with elastin-containing fibrils, where its presence in the endometrium and decidua could be of functional significance. PMID- 9363729 TI - An android body fat distribution in females impairs the pregnancy rate of in vitro fertilization-embryo transfer. AB - To assess if the waist:hip ratio (WHR) is associated with the pregnancy rate (PR) in in-vitro fertilization (IVF) and embryo transfer, waist and hip girths, in addition to height, weight, body mass index (BMI), indications for IVF, PR and other related variables, were measured in 220 women undergoing IVF-embryo transfer. Three variables were significantly negatively associated with PR; high age, smoking and WHR >0.80. Women with WHR between 0.70-0.79 had a PR of 29.9% as compared to 15.9% in women with WHR >0.80 [odds ratio 0.42, 95% confidence interval (CI) 0.2-0.9, P = 0.03]. There were no correlations between BMI and PR, nor were there any significant differences for the indications for IVF-embryo transfer, number of oocytes or oocyte fertilization rate, cleavage rate and number of embryos transferred. The association between a low PR and WHR >0.80 remained unchanged after adjustment for age, BMI, smoking, indication for IVF, parity and number of embryos transferred. In IVF-embryo transfer, fertilization is a laboratory and clinically controlled process, until the embryo is transferred to the uterus. Possible reasons for our finding of a decreased PR in women with an android body fat distribution include a different endocrinological and biochemical milieu for the oocyte in the growing follicle, oocytes of poor quality, or endometrial changes due to hormonal dysfunction. PMID- 9363730 TI - Heparin and low-dose aspirin restore placental human chorionic gonadotrophin secretion abolished by antiphospholipid antibody-containing sera. AB - This study was conducted to determine whether drugs used for conventional treatments of pregnant women with antiphosholipid syndrome might be able to restore the gonadotrophin-releasing hormone (GnRH)-induced secretion of placental human chorionic gonadotrophin (HCG) in vitro. We tested this hypothesis using a modified enzyme-linked immunosorbent assay (ELISA) and an in-vitro placental culture system. Pharmacological dose of low molecular weight heparin (20 IU/ml) significantly (P < 0.02) reduced the antiphospholipid antibody (aPL) binding in the ELISA and was able to restore GnRH-induced HCG secretion (P < 0.05) in presence of aPL-containing sera. Low-dose aspirin (0.03 M) did not modify aPL binding in the ELISA, but partially restored HCG secretion (P < 0.05). These observations may help to explain the role of these treatments in antiphospholipid syndrome. PMID- 9363731 TI - Spontaneous rupture of an unscarred gravid uterus at 32 weeks gestation. PMID- 9363732 TI - Evidence-based ethics and the regulation of reproduction. PMID- 9363733 TI - Convention for the protection of human rights and dignity of the human being with regard to the application of biology and medicine: convention on human rights and biomedicine (adopted by the Committee of Ministers on 19 November 1996). Council of Europe Convention of Biomedicine. PMID- 9363734 TI - Ultrasound guided embryo transfer does not prevent ectopic pregnancies after in vitro fertilization. PMID- 9363735 TI - Chronic genital inflammation in the male--an easily missed diagnosis. PMID- 9363736 TI - Coital rates and sex ratios. PMID- 9363737 TI - Cardiac potassium currents and channels--part I: basic science aspects. PMID- 9363738 TI - The effect of age on cardiovascular risk factors in Chinese women. AB - Chinese women traditionally have a low incidence of coronary heart disease. However, information on cardiovascular risk factors in this population are relatively scarce. We examined these risk factors in 601 Hong Kong Chinese women (age+/-SEM, 38.5+/-0.4 years; range, 18-66 years) stratified into four age groups (group 1, < or =30 years; group 2, 31-40 years; group 3, 41-50 years; group 4, > or =51 years). Increasing age in Chinese women was associated with increased body mass index, waist-to-hip ratio, systolic and diastolic blood pressure, fasting plasma total cholesterol, triglyceride, low-density lipoprotein, apolipoprotein B, fasting and 2-h plasma glucose, glycated haemoglobin, fasting plasma insulin and urate concentrations. After adjustment for body mass index, waist-to-hip ratio and smoking, all these age-related associations remained statistically significant except for fasting plasma insulin concentration. There was a progressive increase with age in the prevalence of glucose intolerance, hypertension, dyslipidaemia and obesity. These prevalence rates further increased in subjects aged 51 years (the mean menopausal age in Asian women) or above. These findings suggest that age had an important and independent effect on cardiovascular risk in Chinese women and that, as in Caucasians, the onset of menopause might further increase this risk. PMID- 9363739 TI - Priming of neutrophils after elective percutaneous transluminal coronary angioplasty is unrelated to accompanying brief myocardial ischemia. AB - OBJECTIVE: The purpose of this study was to investigate the effect of brief myocardial ischemia and vascular trauma induced by elective percutaneous transluminal coronary angioplasty on in vivo 'priming' and activation of neutrophils. PATIENTS AND METHODS: We studied 16 patients undergoing elective coronary angioplasty for symptomatic coronary artery disease and a control group of seven patients undergoing diagnostic cardiac catheterization. Free radical production from purified neutrophils (Ficoll-Hypaque density gradient method) was measured indirectly by the chemiluminescence method. Myocardial ischemia during balloon inflation was assessed by serial lactate determinations from coronary sinus and arterial blood. The degree of transient angioplasty-related myocardial ischemia was related to the oxidative response of activated neutrophils. RESULTS: Mean (+/-S.E.M.) oxidative response, i.e. the lucigenin- and luminol-enhanced chemiluminescence (counts per minute) of neutrophils sampled from the coronary sinus increased significantly after percutaneous transluminal coronary angioplasty (Lucigenin-chemiluminescence: pre-angioplasty 3.69+/-0.64x10(5) vs. post-angioplasty 7.08+/-1.2x10(5), P<0.01; Luminol-chemiluminescence: pre angioplasty 2.81+/-0.67x10(6) vs. post-angioplasty 5.2+/-0.92x10(6), P<0.01). Twelve of 16 patients developed transient cardiac lactate production (mean coronary sinus lactate excess: +0.12 mmol/l) and three disclosed a lactate extraction ratio <10%, both suggestive of myocardial ischemia. However, there was no correlation between the cardiac lactate production and the increased oxidative response after coronary angioplasty (r2 (Lucigenin-chemiluminescence)=0.02, n.s.; r2 (Luminol-chemiluminescence)=0.06, n.s.). CONCLUSION: 'Priming' of neutrophils, as reflected by increased oxidative response, is likely to occur after coronary angioplasty, but not after the angiographic procedure itself. However, 'priming' seems to be unrelated to the transient brief period of myocardial ischemia and rather depends on an alternative mechanism. PMID- 9363740 TI - Effect of ST segment measurement point on performance of exercise ECG analysis. AB - To evaluate the effect of ST-segment measurement point on diagnostic performance of the ST-segment/heart rate (ST/HR) hysteresis, the ST/HR index, and the end exercise ST-segment depression in the detection of coronary artery disease, we analysed the exercise electrocardiograms of 347 patients using ST-segment depression measured at 0, 20, 40, 60 and 80 ms after the J-point. Of these patients, 127 had and 13 had no significant coronary artery disease according to angiography, 18 had no myocardial perfusion defect according to technetium-99m sestamibi single-photon emission computed tomography, and 189 were clinically 'normal' having low likelihood of coronary artery disease. Comparison of areas under the receiver operating characteristic curves showed that the discriminative capacity of the above diagnostic variables improved systematically up to the ST segment measurement point of 60 ms after the J-point. As compared to analysis at the J-point (0 ms), the areas based on the 60-ms point were 89 vs. 84% (p=0.0001) for the ST/HR hysteresis, 83 vs. 76% (p<0.0001) for the ST/HR index, and 76 vs. 61% (p<0.0001) for the end-exercise ST depression. These findings suggest that the ST-segment measurement at 60 ms after the J-point is the most reasonable point of choice in terms of discriminative capacity of both the simple and the heart rate-adjusted indices of ST depression. Moreover, the ST/HR hysteresis had the best discriminative capacity independently of the ST-segment measurement point, the observation thus giving further support to clinical utility of this new method in the detection of coronary artery disease. PMID- 9363741 TI - Effect of oximetry error on the diagnostic value of the Qp/Qs ratio. AB - As a quantitative assessment of the magnitude of shunting, the ratio of pulmonary to systemic blood flow (Qp/Qs) plays an important role not only in the oximetric diagnosis of intracardiac and great-vessel shunts but also in the treatment of the patient. However, the oxygen saturation measurements used to compute the Qp/Qs ratio contain errors due to physiological variability and measurement error of the oximeter used to analyze the blood samples. We have developed a mathematical model to describe the variability that oximetry errors contribute to the uncertainty in the Qp/Qs ratio. Using this model, we compute the probability of making an inappropriate recommendation regarding corrective surgery when a particular value of the ratio is the criterion for surgery, e.g. a Qp/Qs ratio >2. This report also contains a spreadsheet that readers can use to analyze their own oximetry data by computing confidence intervals for the Qp/Qs ratio. The results presented here support the following conclusions. First, because the Qp/Qs ratio is calculated from saturation measurements at four different sites, oximetry errors make the Qp/Qs ratio less effective at detecting the presence of a shunt than the conventional step-up method that depends on samples from only two sites. Second, although oximetry errors are equally likely to cause the calculated Qp/Qs ratio to overestimate the true Qp/Qs ratio as to underestimate it, the overestimations on average have greater magnitudes than the underestimations. Third, in comparison with an oximeter that has 2.5% measurement error, using an oximeter with 1% or less error greatly reduces the uncertainty in the Qp/Qs ratio and thus increases the probability of reaching the right decision regarding corrective surgery. Fourth, the variability in apparent Qp/Qs ratios is also greatly diminished by taking multiple blood samples from each of the four requisite sites and averaging them before calculating the Qp/Qs ratio. Although increasing the number of blood samples from each site can compensate for the error of an oximeter, this approach can be impractical, particularly if the oximeter error is 2.5% or greater. PMID- 9363742 TI - Ischemic versus idiopathic cardiomyopathy: differing neurohumoral profiles despite comparable peak oxygen uptake. AB - OBJECTIVE: We tested the hypothesis that neurohormonal and immunological activation differs in ischemic and idiopathic dilated cardiomyopathy since recent intervention trials indicate that ischemic cardiomyopathy seems to carry a worse prognosis than idiopathic cardiomyopathy of comparable clinical severity. METHODS: In ten patients with ischemic cardiomyopathy undergoing spiroergometric evaluation venous levels of norepinephrine, epinephrine, renin, angiotensin, atrial natriuretic peptide as well as soluble interleukin-2-receptor were determined before, during and 10 min after exercise. Results were compared to sixteen patients with idiopathic cardiomyopathy with similar peak oxygen uptake (13.3+/-3 vs. 13.6+/-3 ml/kg/min; P=ns). RESULTS: In ischemic patients, norepinephrine, angiotensin, and interleukin-2 receptor levels were significantly higher before, during and after exercise. Interleukin-2-receptor levels correlated with angiotensin. CONCLUSIONS: We conclude that in ischemic as compared to idiopathic cardiomyopathy, a more pronounced activation of the sympathetic, renin-angiotensin and T-cell immune system is present at rest, during and after exercise. These data may contribute to explain differences in response to intervention and in prognosis. They warrant further investigation. PMID- 9363743 TI - Multiplane transoesophageal echocardiographic detection of thoracic aortic plaque is a marker for coronary artery disease in women. AB - OBJECTIVE: This study was conducted to examine if the multiplane transoesophageal echocardiographic detection of atherosclerotic plaque in the thoracic aorta could predict the absence or the presence and the severity of significant coronary artery disease in women. Its association with coronary disease is attractive and may have great influence on foregoing routine preoperative cardiac catheterization in patients with valvular heart disease but no data are available in women. METHODS: Clinical and angiographic features and transoesophageal echocardiographic findings were prospectively analysed in 111 women. RESULTS: In 24 women with significant coronary disease, 20 had thoracic aortic plaque on transoesophageal echocardiographic studies. In contrast, aortic plaque existed in only 12 of the remaining 87 women with normal or mildly abnormal coronary arteries. Therefore, the presence of aortic plaque had a sensitivity of 83%, a specificity of 86%, a positive and negative predictive values of 62% and 95%, respectively for the detection of significant coronary disease. There was a significant relation between the severity and the extent of atherosclerotic lesions and the angiographic coronary score (P<0.0001). Multivariate logistic regression analysis revealed that aortic plaque was the most significant independent marker of coronary disease (odds ratio=27.9; 95% confidence interval=5.5-131.6; P<0.0001). CONCLUSIONS: This prospective study indicates that multiplane transoesophageal echocardiographic examination of thoracic atherosclerotic plaque is a marker for coronary disease in women and especially a powerful predictor of absence of significant coronary artery disease. Transoesophageal echocardiographic aortic examination might be used with risk factors and angina symptoms to discuss the need for preoperative coronary angiography in women with valvular heart disease. PMID- 9363744 TI - Indium-111 antimyosin scintigraphy before and after coronary bypass surgery: unexpected preoperative myocardial uptakes. AB - The present study was designed to evaluate 111In-antimyosin scintigraphy in detecting pre- and post-operative myocardial infarction in patients undergoing coronary artery bypass surgery. Fab antimyosin scintigraphy has been shown to be sensitive and specific in detecting myocardial necrosis and to be potentially valuable in situations where other criteria are not reliable. In a previous study, postoperative antimyosin uptakes occurred in 82% of the studied patients. Sixteen consecutive patients with an indication of coronary artery surgery were assessed by preoperative coronary angiography, serial electrocardiograms, and myocardial scanning with 111Indium-labeled antimyosin antibodies performed before and after operation. In four patients, a recent myocardial infarction (1 to 3 months) was detected with an accurate localization when compared to the classic criteria of myocardial infarction. One more patient with a 21-year old myocardial infarction showed an intense uptake whereas there was no recent acute coronary event. Four other patients had an unexpected preoperative uptake, since there were no acute coronary events in their medical history. All preoperative scintigraphic uptakes were still present on the second scan performed postoperatively in these nine patients. Only one patient showed a new postoperative uptake when compared to the preoperative scan which was normal; this postoperative septal infarct was confirmed by a postoperative coronary angiography. Extracardiac uptakes (sternum and ribs) were frequently observed after operation and might hamper the interpretation of postoperative scintigrams. Unexpected preoperative uptakes may be related to non diagnosed small necrosis. A preoperative reference scan is required for an accurate interpretation of a postoperative 111In-antimyosin uptake. Moreover, extracardiac uptakes may limit the interpretation of perioperative cardiac damage. PMID- 9363745 TI - Hypertensive crisis associated with cerebellar embolization due to left atrial myxoma. AB - In this article, we present an unusual case of hypertensive crisis associated with nonhemorrhagic cerebellar infarction due to embolization of loose tumor fragments of left atrial myxoma. PMID- 9363746 TI - Differential splicing of pre-messenger RNA produces multiple forms of mature caprine alpha(s1)-casein. AB - The identity of multiple forms of caprine alpha(s1)-casein in variants A, B, and C has been determined by structural characterisation using mass spectrometry, automated Edman degradation and peptide mapping. Mature goat alpha(s1)-casein exists as a mixture of at least four molecular species which differ in peptide chain length. The main component corresponds to the 199-residues form already described. The other three, in lesser amounts, were shorter forms of alpha(s1) casein and differed for the deleted peptides 141-148, as shown previously for ovine alpha(s1)-casein, peptide 110-117, or Gln78. Analysis of alpha(s1)-casein mRNA from milk somatic cells demonstrated that these forms originated from skipping events at the level of exon 13 (codifying for peptide 110-117) and 16 (codifying for peptide 141-148) and from the presence of a cryptic splice site within exon 11 (whose first CAG triplet encodes Gln78) during primary transcript processing. The finding of these splicing abnormalities in the three common variants A, B, and C suggests that this is a general feature of alpha(s1)-casein in goat. A further source of heterogeneity of caprine alpha(s1)-casein was identified in the discrete phosphorylation of seryl residues. Eight serine residues (at positions 44, 46, 64 to 68 and 75) are fully phosphorylated (except in variant A because of the replacement Glu77-->Gln which prevents phosphorylation of Ser75). Conversely, Ser115 and Ser41 are phosphorylated only to about 50% and 20%, respectively. Ser12, although located in a consensus triplet, is never phosphorylated, similarly to the ovine alpha(s1)-casein variants. These results confirm that there are stabilised mechanisms of simultaneous synthesis of alpha(s1)-casein at different length and of post translational modification in both caprine and ovine species. PMID- 9363747 TI - Apoptotic cell death and caspase 3 (CPP32) activation induced by calcium ionophore at low concentrations and their prevention by nerve growth factor in PC12 cells. AB - A23187 (a calcium ionophore) at low concentration (0.1 microM) induced apoptotic cell death (chromatin condensation and DNA fragmentation) accompanied by the activation of caspase-3 (CPP32), a member of the interleukin-1beta-converting enzyme protease. On the other hand, A23187 at high concentration (2 microM) induced necrotic cell death not accompanied by the activation of CPP32. Nerve growth factor inhibited the cell death and CPP32 activation induced by 0.1 microM A23187, but not the cell death induced by 2 microM A23187. Acylaspartyl-glutamyl valyl-aspartyl-aldehyde, an inhibitor of CPP32, reduced the cell death induced by 0.1 microM A23187. These results suggest that calcium-ion-induced apoptotic cell death was mediated by CPP32 activation in PC12 cells. PMID- 9363748 TI - Cell-growth regulation of the hamster dihydrofolate reductase gene promoter by transcription factor Sp1. AB - The dihydrofolate reductase (DHFR) gene (dhfr) promoter contains cis-acting elements for the transcription factors Sp1 and E2F. Given the ability of Sp1 to activate the dhfr promoter, we have evaluated the contribution of Sp1 to the cell growth regulation of the dhfr gene. Using gel-mobility assays performed with DNA probes from the minimal promoter of the hamster dhfr gene and nuclear extracts from cultured hamster cells (CHO K1) we show that the binding of Sp1 to the dhfr promoter is cell-growth-phase regulated. Accordingly, dhfr transcription and mRNA levels in K1 cells increase upon serum stimulation. Cytological detection of Sp1 by immunofluorescence reveals a decrease of this protein in the process leading to the G0 state, and an increase upon serum stimulation of quiescent cells. These results were confirmed by western blot analysis. It is concluded that Sp1 progressively binds to the hamster dhfr promoter after stimulation of cell proliferation, which can account for the transcriptional regulation of the dhfr gene during the cell cycle. The role of Sp1 in the specific control of dhfr during the cell cycle was confirmed in vivo using cell lines derived from dhfr negative cells transfected with dhfr plasmids carrying either the wild-type or mutated Sp1-binding or E2F-binding sites in the dhfr minimal promoter. PMID- 9363749 TI - Use of anti-(beta2 microglobulin) mAb to study formation of amyloid fibrils. AB - Three mAbs, IgG1k 1F11, 7B6 and 14H3, were raised against in vitro-self aggregated beta2-microglobulin. They recognize the native and unfolded forms of the protein and bind its fibrillar form that is present in amyloid tissue. When assayed in fibrillogenesis tests in vitro, mAb 14H3 inhibited fibril formation from beta2-microglobulin. This mAb recognizes a sequential epitope corresponding to the C-terminal octapeptide, residues 92-99, of beta2-microglobulin. By using synthetic peptides it has been found that the integrity of the sequence is essential for the formation of the immunocomplex: the binding affinity is lowered by one order of magnitude (Kd from 10(-7) M to 10(-6) M) by removal of Met99 and completely abolished when both Asp98 and Met99 are lost or Arg98 is substituted with Lys. The other two mAbs, 1F11 and 7B6, which bind sequences 20-41 and 63-75, respectively, are without effect on beta2-microglobulin fibrillogenesis. These two mAbs recognize beta2-microglobulin bound to the heavy chain in the major histocompatibility complex of type I located in the cell membrane, a property which is not shared by mAb 14H3. PMID- 9363750 TI - Involvement of laser photo-CIDNP (chemically induced dynamic nuclear polarization)-reactive amino acid side chains in ligand binding by galactoside specific lectins in solution. AB - For proteins in solution the validity of certain crystallographic parameters can be ascertained by a combination of molecular-dynamics (MD) simulations and NMR spectroscopy. Using the laser photo-CIDNP (chemically induced dynamic nuclear polarization) technique as a measure for surface accessibility of histidine, tyrosine and tryptophan, the spectra of bovine galectin-1 and Erythrina corallodendron lectin (EcorL) are readily reconcilable with the crystallographic data for these two proteins. The results emphasise the role of Trp68/Trp69 for carbohydrate binding in bovine galectin-1/chicken galectins and of Trp194 in murine galectin-3. This feature derived from the crystal structure of bovine galectin-1 is maintained in solution for the prototype human homologue, two avian galectins and the chimera-type murine galectin-3, as the spectra corroborate the CIDNP-inferable spatial parameters of the four calculated models for binding-site architecture. In EcorL, Tyr106/Tyr108 are constituents of the extended combining pocket, which can be shielded in solution by ligand presence. Discrepancies between results from modelling and CIDNP measurements concern primarily the lack of reactivity of histidine residues for human and avian prototype galectins and of Tyr82/Tyr229 of the plant lectin. Site-directed mutagenesis of EcorL is assumed to provide information on the role of a certain residue for functional aspects. When single-site mutants of EcorL ([Ala106]EcorL, [Ala108]EcorL, [Ala229]EcorL) were subjected to molecular-dynamics (MD) simulations, the apparent surface accessibilities even of spatially separated amino acid side chains could non-uniformly be affected. This conclusion is supported by the assessment of the spectra for the mutant proteins. On the basis of these CIDNP results modelling of the binding-site architecture of the lectin indicates the occurrence of notable alterations in the orientation of Tyr106/Tyr108 phenyl rings. The implied potential effect of single-site mutations on conformational features of a protein will deserve attention for the interpretation of studies comparing wild-type and mutant proteins. PMID- 9363751 TI - Chemical characterization of the predominant proteins secreted by mouse seminal vesicles. AB - Mouse seminal vesicles secrete four major protein components with estimated molecular masses of 95, 38, 17, and 16 kDa. Amino acid sequencing revealed that the 95-kDa component represents a protein with an unknown structure, while the 38 kDa component was identified as semenoclotin, the 17-kDa component as seminal vesicle-secreted protein IV, and the 16-kDa component as seminal-vesicle-secreted protein V. Semenoclotin and the 95-kDa component were readily cross-linked by transglutaminase, suggesting that the two proteins are involved in the formation of the mouse copulatory plug. Treatment of mouse seminal vesicle fluid with human prostate-specific antigen rapidly degraded semenoclotin, indicating a structural resemblance of this protein to human semenogelins, despite the vast difference in primary structure. As previously reported for other seminal-vesicle-secreted proteins, the semenoclotin transcripts are shown to be under androgen control. PMID- 9363752 TI - Anthocyanin 5-aromatic acyltransferase from Gentiana triflora. Purification, characterization and its role in anthocyanin biosynthesis. AB - Acylation with hydroxycinnamic acids stabilizes anthocyanins and makes their colour bluer (bathochromic shift). We purified to homogeneity one acylation enzyme, hydroxycinnamoyl-CoA:anthocyanidin 3,5-diglucoside 5-O-glucoside-6"'-O hydroxycinnamoyltransferase, from blue petals of Gentiana triflora. It is a single polypeptide protein of 52 kDa with a pI of 4.6. It catalyzes the transfer of the p-coumaric acid and caffeic acid from their CoA esters to the 5-glucosyl moiety of anthocyanidin 3,5-diglucosides but could not use malonyl-CoA as an acyl donor. Neither anthocyanidin 3-monoglucoside nor anthocyanins aromatically acylated at the 3-glucosyl moiety could be acylated by this enzyme. Aromatic acylation of anthocyanidin 3,5-diglucoside by this enzyme caused a bathochromic shift and increased pigment stability in neutral to weakly basic pH. Other anthocyanins from the petals of G. triflora were isolated and their structures were determined by fast-atom-bombardment MS and NMR. The biosynthetic pathway of gentiodelphin, a diacylated anthocyanin accumulating in G. triflora petals, is proposed on the basis of these results. PMID- 9363753 TI - SP-22 is a thioredoxin-dependent peroxide reductase in mitochondria. AB - SP-22 is a mitochondrial antioxidant protein in bovine adrenal cortex. The protein is homologous to thioredoxin peroxidase and other antioxidant proteins. It protects radical-sensitive enzymes from oxidative damage by a radical generating system (Fe2+/dithiothreitol) in the presence of a small amount of serum. In this study we purified a second mitochondrial protein with Mr 11,777, which cooperates with SP-22 to protect glutamine synthetase and other proteins from Fe2+/dithiothreitol-mediated damage. Without SP-22, the protein had no protecting activity. We determined amino acid and nucleotide sequences of the protein and its cDNA, respectively, and found that it was a protein of the thioredoxin family. The protein, designated as mt-Trx (mitochondrial thioredoxin), had a presequence composed of 59 amino acids that seemed to be a mitochondrial targeting signal. Mitochondrial extract prepared from adrenal cortex contained NADPH-dependent 5,5'dithiobis(2-nitrobenzoic acid) (Nbs2) reductase activity. The enzyme was thought to have thioredoxin reductase activity, since the Nbs2-reducing activity was stimulated by mt-Trx. We partially purified the Nbs2 reductase from bovine adrenocortical mitochondria. In the presence of the partially purified reductase, mt-Trx, and NADPH, SP-22 showed the activity to protect oxyhemoglobin against ascorbate-induced damage. Furthermore, with the three protein components (Nbs2 reductase, mt-Trx, and SP-22) NADPH was oxidized in the presence of hydrogen peroxide or tert-butyl hydroperoxide. The oxidation of NADPH was concomitant with the disappearance of an equimolar amount of hydrogen peroxide. Without any one of the protein components no hemoglobin protecting and peroxide-dependent NADPH-oxidizing activities were observed. From these results we concluded that SP-22 is thioredoxin-dependent peroxide reductase or so-called thioredoxin peroxidase in mitochondria from the adrenal cortex. PMID- 9363754 TI - Cloning and characterization of the Arabidopsis thaliana SQS1 gene encoding squalene synthase--involvement of the C-terminal region of the enzyme in the channeling of squalene through the sterol pathway. AB - Squalene synthase (SQS) catalyzes the first committed step of the sterol biosynthetic pathway. A full-length Arabidopsis thaliana SQS cDNA has been isolated by combining library screening and PCR-based approaches. Arabidopsis SQS is encoded by a small gene family of two genes (SQS1 and SQS2) which are organized in a tandem array. SQS1 and SQS2 have an identical organization with regard to intron positions and exon sizes and encode SQS isoforms showing a high level of sequence conservation (79% identity and 88% similarity). The isolated cDNA has been assigned to the SQS1 gene product, SQS1. RNA blot analysis has shown that the 1.6-kb SQS1 mRNA is detected in all plant tissues analyzed (inflorescenses, leaves, stems and roots) although the transcript is especially abundant in roots. Arabidopsis SQS1 isoform is unable to complement the SQS defective Saccharomyces cerevisiae strain 5302, although SQS activity was detected in the microsomal fraction of the transformed yeast strain. However, a chimeric SQS resulting from the replacement of the 66 C-terminal residues of the Arabidopsis enzyme by the 111 C-terminal residues of the Schizosaccharomyces pombe enzyme was able to confer ergosterol prototrophy to strain 5302. Labeling studies using [3H]farnesyl-P2 and microsomal fractions obtained from yeast strains expressing either Arabidopsis SQS1 or chimeric Arabidopsis/S. pombe SQS derivatives indicated that the C-terminal region of the enzyme is involved in the channeling of squalene through the yeast sterol pathway. PMID- 9363755 TI - The recombinant product of the Chryptomonas phi plastid gene hlpA is an architectural HU-like protein that promotes the assembly of complex nucleoprotein structures. AB - The HlpA protein which is encoded by the hlpA gene in the plastid genome of the cryptomonad alga Chryptomonas phi is structurally related to the non-sequence specific DNA-binding and DNA-bending HU family of chromatin-associated proteins. The expression of the HlpA protein complements the mutant phenotype of Bacillus subtilis cells impaired in the Hbsu protein (B. subtilis HU), as measured by the resistance of the cells to methylmethane sulphonate. To analyse the interactions of HlpA with DNA, we expressed the protein in Escherichia coli and purified it to homogeneity. HlpA interacts preferentially with four-way junction DNA or DNA minicircles, when compared with linear DNA, recognising DNA structure. HlpA and E. coli HU display comparable affinities for all types of DNA tested; however, HlpA exhibits a stronger tendency to self-associate in the presence of DNA. Accordingly, HlpA oligomerises more readily than HU in protein crosslinking experiments. In the presence of topoisomerase I, HlpA constrains negative superhelical turns in closed circular plasmid DNA. The HlpA protein mediates the joining of distant recombination sites into a complex nucleoprotein structure, as judged by beta-mediated site-specific recombination. The results presented provide evidence that HlpA is a functional plastid equivalent of nuclear and mitochondrial HMG1-like proteins and bacterial HU proteins. PMID- 9363756 TI - Complex regulation of transferrin receptors during erythropoietin-induced differentiation of J2E erythroid cells--elevated transcription and mRNA stabilisation produce only a modest rise in protein content. AB - The regulation of transferrin-receptor synthesis was studied in J2E erythroid cells induced to differentiate with erythropoietin. Nuclear run-on assays demonstrated that transcription of the transferrin-receptor gene rose markedly after erythropoietin treatment. In addition, transferrin-receptor mRNA was stabilised and this was associated with an increase in the activity of the RNA binding protein IRP (iron regulatory protein). As a result of increased transcription and mRNA stabilisation, steady-state RNA levels increased 10-20 fold. However, despite these large increases in mRNA, translation only doubled; consequently, modest increases in total protein and surface transferrin receptors were observed. Moreover, this rise in transferrin receptors was transient, and correlated with a burst of proliferation shortly after erythropoietin treatment. The expected inverse relationship between transferrin receptors and ferritin did not occur during J2E maturation as translation of both ferritin subunits increased when transferrin-receptor mRNA levels rose. Analysis of mutant J2E clones incapable of synthesising haemoglobin revealed that surface transferrin receptor levels were only 15-25% that of the parental erythroid line. We propose that the surface expression of transferrin receptors in J2E cells is governed by three factors: basal levels essential for normal growth in culture; elevated levels needed for haemoglobin synthesis; and a transient erythropoietin-induced increase that is required for the final burst of proliferation. It was concluded that the regulation of transferrin-receptor production in erythropoietin stimulated J2E cells is complex and that there are several sites of control. PMID- 9363757 TI - The BH3 domain of Bax is sufficient for interaction of Bax with itself and with other family members and it is required for induction of apoptosis. AB - bax is an apoptosis-inducing member of the bcl-2 multigene family. We have studied interactions of human Bax with itself, and with the apoptosis-preventing members Bcl-2 and Bcl-xL using a yeast two-hybrid system. Exhaustive Bax truncations were constructed and their interactions with full-length family members studied. Bax interacted similarly with itself as with the apoptosis suppressing family members Bcl-2 and Bcl-xL in quantitative two-hybrid studies. A region of 41 amino acids covering the recently discovered BH3 domain of Bax was found to be necessary and sufficient for all interactions of Bax. Bax truncations containing BH3, but lacking BH1 and BH2 homology domains, interacted with the other family members markedly more strongly than full-length Bax, which may reflect conformational changes required for the interactions of full-length Bax. The minimum requirements for Bax homodimerization were found to be the BH3 domain from one Bax molecule and a region covering BH3 plus BH1 from another. We also studied the apoptosis-inducing activity of the Bax truncations upon microinjection of expression plasmids into rat fibroblasts. The BH3 region was required for the apoptosis-inducing activity of Bax, whereas BH1, BH2 and the N terminus of Bax were dispensable. PMID- 9363758 TI - Okadaic acid interferes with phorbol-ester-mediated down-regulation of protein kinase C-alpha, C-delta and C-epsilon. AB - A prolonged cell exposure of all examined cell types to tumour-promoting phorbol esters leads to a substantial inactivation and degradation of protein kinase C (PKC), a phenomenon known as down-regulation. With a combination of one- and two dimensional immunoblot analyses we have previously shown the existence in PC12 cells of distinct PKC-alpha forms that differentially respond to cell treatment with phorbol ester [Gatti, A. & Robinson, P. J. (1996) J. Biol. Chem. 271, 31 718 31722]. Using the same experimental model, in the present study we investigated a possible relationship between PKC-alpha phosphorylation and its down-regulation. The exposure of PC12 cells to okadaic acid, a potent inhibitor of biologically relevant protein phosphatases, was found to partially protect PKC-alpha against phorbol-ester-mediated down-regulation. Further, a similar protective effect of okadaic acid was observed for PKC-delta and PKC-epsilon, which are also expressed in PC12 cells. These results indicate that the tumour-promoting activity of okadaic acid itself may be due to a sustained phosphorylation of PKC. PMID- 9363759 TI - Protein phosphatase beta, a putative type-2A protein phosphatase from the human malaria parasite Plasmodium falciparum. AB - Protein phosphatases play a critical role in the regulation of the eukaryotic cell cycle and signal transduction. A putative protein serine/threonine phosphatase gene has been isolated from the human malaria parasite Plasmodium falciparum. The gene has an unusual intron that contains four repeats of 32 nucleotides and displays a high degree of size polymorphism among different strains of P. falciparum. The open reading frame reconstituted by removal of the intron encodes a protein of 466 amino acids with a predicted molecular mass of approximately 53.7 kDa. The encoded protein, termed protein phosphatase beta (PP beta), is composed of two distinct domains. The C-terminal domain comprises 315 amino acids and exhibits a striking similarity to the catalytic subunits of the type-2A protein phosphatases. Database searches revealed that the catalytic domain has the highest similarity to Schizosaccharomyces pombe Ppa1 (58% identity and 73% similarity). However, it contains a hydrophilic insert consisting of five amino acids. The N-terminal domain comprises 151 amino acid residues and exhibits several striking features, including high levels of charged amino acids and asparagine, and multiple consensus phosphorylation sites for a number of protein kinases. An overall structural comparison of PP-beta with other members of the protein phosphatase 2A group revealed that PP-beta is more closely related to Saccharomyces cerevisiae PPH22. Southern blots of genomic DNA digests and chromosomal separations showed that PP-beta is a single-copy gene and is located on chromosome 9. A 2800-nucleotide transcript of this gene is expressed specifically in the sexual erythrocytic stage (gametocytes). The results indicate that PP-beta may be involved in sexual stage development. PMID- 9363760 TI - Purification and characterization of transcription factor IIIA from higher plants. AB - Transcription factor IIIA (TF IIIA) binds and specifically activates transcription of eukaryotic 5S rRNA genes. It also forms a 7S ribonucleoprotein complex with mature 5S rRNA. Here, we describe the purification and properties of pTF IIIA from higher plants. The purified protein from tulip (Tulipa whittalii) has a molecular mass of about 40 kDa and also binds 5S rRNA and 5S rRNA genes. pTF IIIA also facilitates the transcription of a 5S rRNA gene in a HeLa cell extract. PMID- 9363761 TI - Differential stimulation by CCAAT/enhancer-binding protein alpha isoforms of the estrogen-activated promoter of the very-low-density apolipoprotein II gene. AB - The transcription factors CCAAT/enhancer-binding proteins alpha and beta (C/EBP alpha and C/EBP beta) are highly expressed in liver and are believed to function in maintaining the differentiated state of the hepatocytes. C/EBP alpha appears to be a critical regulator of genes involved in metabolic processes. We are interested in the roles of C/EBP in the expression of the very-low-density apolipoprotein II (apoVLDL II) gene. This gene encodes an avian yolk protein, is induced by estrogens and is only expressed in liver. To examine the role of C/EBP in apoVLDL II expression, footprinting and electromobility-shift analysis were performed. For three of the protein-binding sites in the apoVLDL II promoter region, C/EBP alpha and C/EBP beta were identified as the major DNA-binding activities. For one of the C/EBP genes, C/EBP alpha, the effect of the gene products on apoVLDL II transcription was examined. From transfection experiments we conclude that maximal estrogen-dependent activity of the apoVLDL II promoter requires the dual action of the estrogen receptor and C/EBP. The level of activity is different depending on the nature of the C/EBP alpha translational isoform transfected, the full-length C/EBP alpha polypeptide being the most active isoform and the N-terminally truncated isoform being moderately active. The present results suggest a role of C/EBP alpha translational isoform ratio in the modulation of expression of C/EBP target genes, such as those involved in metabolic processes. PMID- 9363762 TI - Role of protein-phosphorylation events in the anoxia signal-transduction pathway leading to the inhibition of total protein synthesis in isolated hepatocytes. AB - Incubation of isolated hepatocytes under N2/CO2 (no O2) produced a rapid and strong inhibition of overall polypeptide biosynthesis, which was neither related to cell death nor to the appearance of specific stress proteins. Treatment of the cells with the tyrosine-kinase inhibitor genistein or with the serine/threonine protein-kinase inhibitor H7 did not modify the impairment of protein synthesis induced by oxygen deprivation, indicating that such signal-transduction pathways are probably not involved in the anoxia-mediated effect. Okadaic acid (100 nM) and Na3VO4 (1 mM) reduced the incorporation of [14C]Leu into proteins of hepatocytes maintained under aerobic conditions (93.3 kPa O2). The effects of oxygen deprivation and okadaic acid were additive, whereas sodium vanadate did not enhance the impairment of protein synthesis induced by anoxia. This observation suggests that a common mechanism, involving the net phosphorylation of protein tyrosine residues, that is insensitive to genistein might participate in the negative control of the translation induced by oxygen deprivation. The effect of anoxia on the synthesis of proteins was fully and rapidly reversible upon the restoration of oxygen supply, thus indicating that hepatocytes are able to sense O2. Although high concentrations of cobalt chloride partially mimic the effect of oxygen deprivation on protein biosynthesis, the nature of such an oxygen sensor remains unknown, and appears unlikely to be a part of a classic haem protein. PMID- 9363763 TI - Interaction of the recombinant S100A1 protein with twitchin kinase, and comparison with other Ca2+-binding proteins. AB - The giant myosin-associated twitchin kinase, a member of the Ca2+-regulated protein kinase superfamily, is activated by the EF-hand protein S100A1 in a Ca2+ dependent and Zn2+-enhanced manner. We used recombinant S100A1 to further characterize the interaction between the two proteins. Zn2+ enhanced the binding of Ca2+/S100A1 to twitchin kinase fragments (Kd < 50 nM) in assays using a BIAcore biosensor by reducing the S100A1 off rate. Other Ca2+-binding proteins (S100A6, calmodulin, and the calmodulin-like domain of Ca2+-dependent protein kinase alpha) bound to the kinase but did not activate it. These results indicate that binding of Ca2+-binding proteins alone is insufficient to trigger the intramolecular rearrangement of kinase autoinhibitory contacts required for twitchin kinase activation that is specifically elicited by the S100A1 protein. Kinase fragments that contained only the autoinhibited catalytic sequence or an additional immunoglobulin-like domain had very similar properties, indicating that the tethered immunoglobulin-like domain does not modulate kinase regulation. PMID- 9363765 TI - Peptide fragments of DNA topoisomerase II with helix-forming and coiled-coil forming properties act as inhibitors of the enzyme. AB - We have previously shown that a synthetic peptide (dL) consisting of amino acids 1013-1056 of human alpha topoisomerase II adopted an alpha-helix structure and formed a stable dimer coiled-coil in solution [Frere, V., Sourgen. F., Monnot, M., Troalen, F. & Fermandjian, S. (1995) J. Biol. Chem. 270, 17502-17507]. Here we studied two peptides, dP and dLshort, which are related to dL but which have a double substitution Leu1026-->Pro, Leu1037-->Pro and a deletion of the 15 C terminal residues, respectively. The peptides were studied for their ability to form alpha-helix structures, coiled coils, and to inhibit topoisomerase II activity. In combining circular dichroism spectra with AGADIR prediction for helix structures, we demonstrated that the dLshort peptide, like its parent dL peptide, adopts an alpha-helix structure and can autoassociate into coiled-coils, while dP is completely devoid of such properties. Remarkably, only the dL and dLshort peptides act as good inhibitors of topoisomerase II in various in vitro assays. However, the dLshort peptide has a stronger helix potential and behaves as a much more potent inhibitor (5 microM versus 200 microM) compared to the dL peptide. All these data strongly suggest that the greater inhibitory effect demonstrated by the dLshort peptide is related to its higher ability to form a stable amphiphilic helix, which in turn better recognizes its homologous helical segment in topoisomerase II. Finally, we propose that the dL and the dLshort peptides could interfere with the enzymatic activity of topoisomersase II in modifying its autoassociation or translocation properties. Such peptides may serve as useful models for developing simpler and more specific inhibitors of topoisomerase II. PMID- 9363764 TI - Cross-linking of chloroplast F0F1-ATPase subunit epsilon to gamma without effect on activity. Epsilon and gamma are parts of the rotor. AB - Cys residues were directed into positions 17, 28, 41 and 85 of a Cys6-->Ser mutant of subunit epsilon of spinach chloroplast F0F1 ATP synthase. Wild-type and engineered epsilon were expressed in Escherichia coli, purified in the presence of urea, refolded and reassembled with spinach chloroplast F1 lacking the epsilon subunit [F1(-epsilon)]. Cys-containing epsilon variants were modified with a sulfhydryl-reactive photolabile cross-linker. Photocross-linking of epsilon to F1(-epsilon) yielded the same SDS gel pattern of cross-link products independent of the presence or absence of Mg2+ x ADP, phosphate and Mg2+ x ATP. Epsilon (wild type) [Ser6,Cys28]epsilon and [Ser6,Cys41]epsilon were cross-linked with subunit gamma. With chloroplast F0F1 the same cross-link pattern was obtained, except for one extra cross-link, probably between [Ser6,Cys28]epsilon and F0 subunit III. [Ser6,Cys17]epsilon and [Ser6,Cys85]epsilon did not produce cross-links. Cross linking of epsilon, [Ser6,Cys28]epsilon, [Ser6,Cys41]epsilon to gamma in soluble chloroplast F1 impaired the ability of epsilon to inhibit Ca2+-ATPase activity. The Mg2+-ATPase activity of soluble F1 (measured in the presence of 30% MeOH) was not affected by cross-linking epsilon with gamma. Functional reconstitution of photophosphorylation in F1-depleted thylakoids was observed with F1 in which gamma was cross-linked to [Ser6,Cys28]epsilon or [Ser6,Cys41]epsilon but not with wild-type epsilon. In view of the intersubunit rotation of gamma relative to (alphabeta)3, which is driven by ATP hydrolysis, gamma and epsilon would seem to act concertedly as parts of the 'rotor' relative to the 'stator' (alphabeta)3. PMID- 9363766 TI - Transferrin--interactions of lactoferrin with hydrogen carbonate. AB - The interaction of apolactoferrin with hydrogen carbonate (bicarbonate) has been investigated in the pH range 6.5-9.2. In the absence of bicarbonate apolactoferrin loses a single proton with pK1a of 8.10. This proton loss is independent of the interaction with the synergistic anion. The C-site of apolactoferrin interacts with bicarbonate with a very low affinity (K(-1)C = 3.2 M(-1)). This process is accompanied by a proton loss, which is probably provided by the bicarbonate in interaction with the protein. This proton loss can possibly be the result of a shift in the proton dissociation constant, pKa, of the bicarbonate/carbonate acid/base equilibrium, which would decrease from pKa 10.35 to pK2a 6.90 in the bicarbonate-lactoferrin adduct. The N-site of the protein interacts with bicarbonate with an extremely low affinity, which excludes the presence of the N-site-synergistic anion adduct in neutral physiological media. Contrary to serum transferrin, the concentration of the apolactoferrin in interaction with bicarbonate is pH dependent. Between pH 7.4 and pH 9 with [HCO3 ] about 20 mM, the concentration of the serum transferrin-bicarbonate adduct is always about 30%, whereas that of the apolactoferrin-synergistic anion adduct varies from 25% at pH 7.5 to 90% at pH 9. This implies that, despite an affinity for bicarbonate two orders of magnitude lower than that of serum transferrin, lactoferrin interacts better with the synergistic anion. This can be explained by the possible interaction of lactoferrin with carbonate in neutral media, whereas transferrin only interacts with bicarbonate. PMID- 9363767 TI - Phorbol-ester-activated protein kinase C-alpha lacking phosphorylation at Ser657 is down-regulated by a mechanism involving dephosphorylation. AB - Protein kinase C (PKC) is a key enzyme in the intracellular signaling network. Upon activation by 12-O-tetradecanoylphorbol 13-acetate, the alpha-isoform of PKC translocates to the detergent-soluble and the detergent-insoluble fractions. Besides cofactors, the activity and stability of this protein is critically regulated by multisite phosphorylations. At least three distinct sites, Thr497, Thr638 and Ser657, are involved. We have previously shown that the replacement of Ser657 by alanine leads to a premature down-regulation in the detergent soluble compartment of LLC-PK1 cells [Gysin, S. & Imber, R. (1996) Eur. J. Biochem. 240, 747-750]. More detailed analysis revealed that, in contrast to the wild-type molecule, the down-regulation of the mutant protein is in vivo preceded by a rapid dephosphorylation after phorbol-ester-induced translocation to both the detergent-soluble and insoluble compartments. The [Ala657]PKC-alpha mutant protein molecule showed in vitro a strongly increased sensitivity towards protein phosphatase 2A whereas its overall proteolytic sensitivity remained unchanged when compared to wild type. The in vitro studies led to the suggestion that further dephosphorylation of the mutant protein is a prerequisite in order to become proteolytically down-regulated. Therefore phosphorylation of Ser657 controls the duration of activation of this PKC isozyme upon agonist-induced translocation by preventing premature proteolytic down-regulation via protecting the protein from dephosphorylation. PMID- 9363768 TI - Purification and characterization of two isoforms of isopentenyl-diphosphate isomerase from elicitor-treated Cinchona robusta cells. AB - In Cinchona robusta (Rubiaceae) cell suspension cultures, the activity of the enzyme isopentenyl-diphosphate isomerase (isopentenyl-POP isomerase) is transiently induced after addition of a homogenate of the phytopathogenic fungus Phytophthora cinnamomi. The enzyme catalyses the interconversion of isopentenyl POP and dimethylallyl diphosphate (dimethylallyl-POP) and may be involved in the biosynthesis of anthraquinone phytoalexins that accumulate rapidly after elicitation of Cinchona cells. From elicitor-treated C. robusta cells, two isoforms of isopentenyl-POP isomerase have been purified to apparent homogeneity in four chromatographic steps. The purified forms are monomeric enzymes of 34 kDa (isoform I) and 29 kDa (isoform II), with Km values for isopentenyl-POP of 5.1 microM and 1.0 microM, respectively. Both isoforms require Mn2+ or Mg2+ as cofactor, isoform II showing a preference for Mn2+ with maximum activity at 1.5-2 mM. Isoform I was most active in the presence of 0.5-1.5 mM Mg2+ or in the presence of 0.5 mM Mn2+. A pH optimum of 7-7.8 was found for both forms and both were competitively inhibited by geranyl diphosphate (Ki 96 microM for isoform I) and the transition state analogue 2-(dimethylamino)ethyl diphosphate. Rechromatography of purified isoforms did not indicate any interconversion of both forms. Western blot analysis, using antibodies raised against isopentenyl POP isomerase purified from Capsicum annuum, showed the presence of both isoforms in the crude protein extracts from C. robusta cells. Isoform II was specifically induced by elicitation, non-treated cells contained low activity of this isoform. The possible role of isopentenyl-POP isomerase in the biosynthesis of anthraquinones is discussed. PMID- 9363769 TI - Substrate specificity of cathepsins D and E determined by N-terminal and C terminal sequencing of peptide pools. AB - Degradation of protein antigens by cellular proteases is a crucial step in the initiation of a T-cell-mediated immune response. But still little is known about the enzymes responsible for the processing of antigens, including their specificity. In this paper, we show that the combination of automated N-terminal sequencing with a newly developed method for C-terminal sequencing of peptide pools generated by the aspartic proteases cathepsins D and E is a fast and easy method to obtain detailed information of the substrate specificity of these endopeptidases. Using a 15-residue synthetic peptide library and a native protein as substrates, we confirm and extend the knowledge about the cleavage motif of cathepsin E where positions P1 and P1' of the substrate must be occupied exclusively by hydrophobic amino acids with aromatic or aliphatic side chains. However, Val and Ile residues are not allowed at position P1. Position P2' accepts a broad range of amino acids, including charged and polar ones. Additional requirements concerning the substrate positions P3' and P4' were also defined by pool sequencing. Furthermore, pool sequencing analysis of melittin digests with the aspartic proteases cathepsin D and E provided evidence that both enzymes share the same cleavage motif, identical to the one derived from the peptide library and the native protein. Therefore, pool sequencing analysis is a valuable and fast tool to determine the substrate specificity of any endopeptidase. PMID- 9363770 TI - Further insights into the mechanism of action of methylmalonyl-CoA mutase by electron paramagnetic resonance studies. AB - Novel analogues of methylmalonyl-CoA and succinyl-CoA have been prepared and used for mechanistic investigations on the coenzyme-B12-dependent methylmalonyl-CoA mutase. 1-Carboxyethyl-CoA (1) and 2-carboxyethyl-CoA (2) as well as their sulphoxides (3 and 4) were moderately good inhibitors with Ki values 4-20 times higher than the Km for succinyl-CoA. 2-Carboxyethyl-CoA (2) and its sulphoxide 4 induced EPR signals when bound to the enzyme-coenzyme-B12 complex. The EPR spectrum of 2 and its sulphoxide 4 differed very much from those induced by the other substrates. In the case of 2 the EPR spectrum of the holoenzyme/inhibitor complex showed the presence of an organic radical coupled to cobal(II)amin. The same experiment with 4 leads to the formation of enzyme-bound cobal(II)amin with no detectable organic radical. The analogues 1 and 3 exhibited higher Ki values and did not induce EPR signals binding to the enzyme-coenzyme-B12 complex. Formyl CoA and acrylate inhibited the enzyme synergistically but were unable to induce EPR signals and to form the product. Ethylmalonyl-CoA, known as a poor substrate, induced a similar but less intense EPR signal than the natural substrate methylmalonyl-CoA. The results are discussed in terms of the mechanism of the methylmalonyl-CoA mutase reaction. PMID- 9363771 TI - Characterization of a recombinant Neisseria meningitidis alpha-2,3 sialyltransferase and its acceptor specificity. AB - The structure and specificity of the recombinant alpha-2,3-sialyltransferase from Neisseria meninigitidis are reported. This enzyme showed an unusual acceptor specificity in that it could use alpha-terminal and beta-terminal Gal residues as acceptors. In addition (beta1-->4)-linked and (beta1-->3)-linked terminal Gal served as acceptors. These properties distinguish the bacterial enzyme from the more widely investigated mammalian equivalents. The protein was expressed as a membrane-associated protein in Escherichia coli at a level of 750 U/l (approximately 250 mg/l). The protein could be extracted with buffers containing 0.2% Triton X-100 and purified to homogeneity using immobilized-metal-affinity chromatography. Electrospray-ionization mass spectrometry of peptides obtained by cleavage with cyanogen bromide and trypsin confirmed over 95% of the deduced amino acid sequence. When used for enzymatic synthesis in coupled reactions with recombinant CMP-Neu5Ac synthetase, the alpha-2,3-sialyltransferase could sialylate fluorescent derivatives of N-acetyllactosamine with N-acetylneuraminic acid, N-propionylneuraminic acid and N-glycoloylneuraminic acid. PMID- 9363772 TI - Primary structure of 21 novel monoantennary and diantennary N-linked carbohydrate chains from alphaD-hemocyanin of Helix pomatia. AB - The primary structures of 21 novel monoantennary and diantennary N-glycans of the glycoprotein alphaD-hemocyanin (alphaD-Hc) of Helix pomatia have been determined. Outer oligosaccharide fragments (antennae) were released from the glycoprotein by Smith degradation of an alphaD-Hc pronase digest. The major antenna, obtained following HPLC fractionation on Lichrosorb-NH2, was characterized using 1H-NMR spectroscopy, fast-atom-bombardment mass spectrometry, and linkage analysis, and corresponds to a pentasaccharide fragment. The intact carbohydrate chains of alphaD-Hc were released with peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase-F digestion, separated from the protein on Bio-Gel P-100, and subfractionated on Bio-Gel P-4. A portion of subfractions was reduced with sodium borodeuteride, and the non-reduced and reduced samples were further fractionated on CarboPac PA-1, Lichrosorb-NH2/Lichrosphere-NH2, and/or Lichrosphere-C18. Purified oligosaccharides and oligosaccharide-alditols were analyzed using 500/600-MHz 1H-NMR spectroscopy. In total, four novel types of antenna were identified, namely, [structures: see text] which are all attached to O-2 of alphaMan residues of the trimannosyl-N,N'-diacetylchitobiose core element, which is generally beta-1,2-xylosylated and alpha-1,6-fucosylated, Man(alpha1 6)[Man(alpha1-3)][+/-Xyl(beta1-2)]Man(beta1-4)GlcNAc(beta1-4) [+/-Fuc(alpha1 6)]GlcNAc. PMID- 9363773 TI - Dependence of the lytic activity of the N-terminal domain of human perforin on membrane lipid composition--implications for T-cell self-preservation. AB - The kinetics and thermodynamics of pore formation by the 22-residue N-terminal domain of human perforin-(1-22)-peptide have been studied for a variety of model phospholipid membranes. Peptide binding and aggregation, and cell lysis were monitored through the change in the fluorescence of Trp, or vesicle-encapsulated carboxyfluorescein, respectively. Peptide binding was analyzed in terms of a model that incorporates non-ideal interactions and aggregation in a membrane bilayer. The minimum number of peptide monomers required to form an active pore averaged from four to six, according to the lipid composition of the vesicle. This combined kinetic and thermodynamic approach has provided quantitative information that allows a direct comparison of the binding behavior of the perforin-(1-22)-peptide in different lipid vesicles and affords molecular insight on the factors controlling pore formation. Pore formation is most favorable in thinner membranes with low melting temperatures. No significant difference in activity is observed for different zwitterionic headgroups. Rather, the gel state of the lipid chain, which diminishes the incorporation and aggregation of the perforin-(1-22)-peptide shows the strongest influence. This effect is observed in both the thermodynamic (incorporation isotherm) and kinetic (carboxyfluorescein release) studies. Insertion and aggregation are more facile in membranes with less densely packed lipids. The dependence of pore-forming activity on lipid composition provides important clues to understanding the self-protection mechanism employed by cytotoxic T lymphocytes (CTL) against perforin-mediated lysis. PMID- 9363774 TI - Ordered cell cycle phase perturbations in Chinese hamster ovary cells treated with an S-adenosylmethionine decarboxylase inhibitor. AB - The polyamines putrescine, spermidine, and spermine are needed for normal cell cycle progression and polyamine-depleted cells cease to proliferate. We have investigated cell cycle perturbations in Chinese hamster ovary cells seeded in the presence of 4-amidinoindan-1-one 2'-amidinohydrazone (CGP 48664), a potent inhibitor of S-adenosylmethionine decarboxylase, an enzyme which is essential for the synthesis of spermidine and spermine. At 9 h and at 1, 2, and 3 days after seeding, cells were labelled with the thymidine analog bromodeoxyuridine (BrdUrd) for 30 min, after which the BrdUrd-containing medium was removed and the cells were allowed to progress through the cell cycle in BrdUrd-free medium before sampling (post-labelling time). Using flow cytometry, coupled with an indirect immunofluorenscence technique, utilizing monoclonal anti-BrdUrd and secondary fluorescein-isothiocyanate-conjugated antibodies, and the DNA stain propidium iodide, cellular BrdUrd and DNA contents were quantified. By investigating the movement of BrdUrd-nonlabelled G1 cells into S phase during the post-labelling time, a measure of the G1/S transition was obtained. The time of appearence in G1 of BrdUrd-labelled cells which had divided was used to monitor the length of the G2+M phase. A measure of the S phase length (DNA synthesis time) was obtained by monitoring the progression of BrdUrd-labelled cells through S phase. CGP 48664 induced spermine depletion significantly increased the length of the S phase already 9 h after seeding cells in the presence of the inhibitor. No effects on the G1/S transition or on the length of the G2+M phase were observed until 2 days after seeding. PMID- 9363775 TI - Human and murine serine-palmitoyl-CoA transferase--cloning, expression and characterization of the key enzyme in sphingolipid synthesis. AB - Serine palmitoyltransferase (SPT, EC 2.3.1.50) is the key enzyme in sphingolipid biosynthesis. It catalyzes the pyridoxal-5'-phosphate-dependent condensation of L serine and palmitoyl-CoA to 3-oxosphinganine. Human expressed-sequence-tag (EST) clones are similar to the two yeast genes for synthesis of long-chain bases, LCB1 and LCB2, which are believed to encode two subunits of SPT [Buede, R., Pinto, W. J., Lester, R. L. & Dickson, R. C. (1991) J. Bacteriol. 173, 4325-5332; Nagiec, M. M., Baltisberger, J. A., Wells, G. B., Lester, R. L. & Dickson, R. C. (1994) Proc. Natl Acad. Sci. USA 91, 7899-7902]. We have cloned and characterized two complete human and murine cDNA sequences named hLCB1 & mLCB1 and hLCB2 & mLCB2, respectively, similar to the yeast LCB1 and LCB2 genes. Human embryonic kidney cells (HEK 293) transfected with murine sequences of LCB1 (mLCB1) and LCB2 (mLCB2) independently and in coexpression showed an overexpression of the transcripts on the mRNA and protein level. The enzymatic activity of cells expressing mLCB2 alone or coexpressed with mLCB1 was three times higher than the activity of untransfected HEK cells. mLCB1 expression was not required for the synthesis of 3-oxo-sphinganine in mammalian cells. Transcription/translation in vitro yielded mLCB1 (53 kDa) and mLCB2 (63 kDa). The two proteins do not contain a signal peptide nor are they glycosylated. The endogenous and overexpressed SPT activity were both sensitive to common SPT inhibitors. Labeling studies with [1 (14)C]palmitic acid indicated that cell lines transfected with mLCB2 preferentially use the excess sphingoid bases for glucocerebroside and galactocerebroside synthesis. Our results provide conclusive genetic and biochemical evidence that the human and murine LCB2 genes described here encode serine palmitoyltransferase. Further studies will be required to unravel the function of the LCB1 gene in mammalian cells. PMID- 9363776 TI - Influence of mutations in hexose-transporter genes on glucose repression in Kluyveromyces lactis. AB - The variability of Kluyveromyces lactis strains in sensitivity to glucose is correlated with genetic differences in Kluyveromyces hexose transporter (KHT) genes. The glucose sensitive strain JA6 was shown to contain an additional gene, KHT2, not found in strains that are less sensitive. KHT2 is tandemly arranged with KHT1 which is identical to the low-affinity transporter gene RAG1, except for the C-terminus. Sequence analysis indicated that most of KHT2 had been lost by a recombination event between KHT1 and KHT2 generating the chimeric gene RAG1. Recombination between KHT1 and KHT2 was also found in mutants of JA6 selected as 2-deoxyglucose resistant colonies. These mutants, like kht1 kht2 double mutants were unable to grow on glucose when respiration was blocked (Rag- phenotype) and glucose repression was strongly reduced. kht1 or kht2 single mutants of JA6 were Rag+ but still an influence of the kht mutations on glucose repression was detectable. Repression was not affected in a Rag- mutant deleted for the phosphoglucose isomerase gene suggesting that the influence of transporter genes on repression is not caused by a reduction of the glycolytic flux. The data rather suggest that sensitivity to glucose repression is dependent on the rate of glucose uptake. PMID- 9363777 TI - Molecular cloning and expression of an interferon-inducible protein encoded by gene 203 from the gene 200 cluster. AB - We report here the complete coding sequence of a 203 cDNA, a member of the interferon-inducible Ifi 200 gene family. By combining reverse-transcriptase PCR and rapid amplification of cDNA ends (RACE) techniques we have obtained a 3.8-kb cDNA corresponding to a 203 mRNA. When used as a probe in northern analysis, its 3' segment hybridized to a 3.8-kb interferon-inducible mRNA, whereas the 5'-end additionally hybridized to a less abundant interferon-inducible 1.8-kb mRNA. Nucleotide sequence analysis revealed that the two mRNAs share the 5' untranslated region and the same open reading frame, which encodes a hydrophilic protein composed of 408 amino acids. The difference between them is due to a 3' untranslated region extended by alternative polyadenylation site selection. Furthermore, 203 mRNA was found to be inducible by interferon-alpha in various murine cell lines. Using polyclonal antibodies raised against a segment specific for the 203 protein, we established that p203 protein levels increase on treatment with interferon-alpha in murine fibroblasts and that p203 is located in the nucleus. PMID- 9363778 TI - The mechanism of tubulin-colchicine recognition--a kinetic study of the binding of a bicyclic colchicine analogue with a minor modification of the A ring. AB - 2-Methoxy-5-(2',3',4'-trimethoxy)-2,4,6-cycloheptatrien-1-one (MTC) is a colchicine analogue that lacks the B ring. 2-Methoxy-5-(2',4'-dimethoxyphenyl) 2,4,6-cycloheptatrien-1-one (MD) is an A-ring analogue of MTC, in which one methoxy group is replaced by a hydrogen atom. This paper describes the kinetic features of MDC binding to tubulin, and compares its behaviour with MTC to analyse the effect of the A-ring modification on the recognition process by tubulin. Binding is accompanied by a strong enhancement of MDC fluorescence and quenching of protein fluorescence. The kinetic and thermodynamic parameters were obtained from fluorescence stopped-flow measurements. The kinetics are described by a single exponential, indicating that this drug does not discriminate between the different tubulin isotypes. The observed pseudo-first-order rate constant of the fluorescence increase upon binding increases in a non-linear way, indicating that this ligand binds with a similar overall mechanism as colchicine and MTC, consisting of a fast initial binding of low affinity followed by a slower isomerisation step leading to full affinity. The K1 and k2 values for MDC at 25 degrees C were 540 +/- 65 M(-1) and 70 +/- 6 s(-1) respectively. From the temperature dependence, a reaction enthalpy change (deltaH(o)1) of the initial binding of 49 +/- 11 kJ/mol(-1) and an activation energy for the second step of 28 +/- 9 kJ/mol(-1) were calculated. Displacement experiments of bound MDC by MTC allowed the determination of a rate constant of reverse isomerisation of 0.60 +/- 0.07 s(-1) at 25 degrees C and the activation energy of 81 +/- 6 kJ/mol(-1). The overall binding constant was (6.3 +/- 0.2) x 10(4) M(-1) at 25 degrees C. Combination of these results with the kinetic parameters for association gives a full characterisation of the enthalpy pathway for the binding of MDC. The pathway of MDC is shown to differ considerably from that of MTC binding. Since its structural difference is located in ring A, this result indicates the use of ring A in the first step. The kinetics of the binding of MDC in the presence of some A ring colchicine analogues (podophyllotoxin, 3',4',5'-trimethoxyacetophenone and N acetylmescaline) and a C-ring analogue (tropolone methyl ether) suggest that the A and C rings are involved in the binding of MDC. PMID- 9363779 TI - Solution structure of reduced microsomal rat cytochrome b5. AB - The solution structure of the major form of the reduced soluble fragment of rat microsomal cytochrome b5 has been solved through 1H-NMR spectroscopy. The protein contains 98 amino acids. Proton assignment was available for residues 1-94, except 90 [Guiles, R. D., Basus, V. J., Kuntz, I. D. & Waskell, L. (1992) Biochemistry 31, 11,365-11,375] and has been confirmed. From 1722 NOEs, of which 1203 were found to be meaningful, a family of 40 energy-minimized structures has been obtained with average backbone rmsd (for residues 5-89) of 0.078 +/- 0.018 nm and average target function of 0.0045 nm2, no distance violations being larger than 0.029 nm. The structure has been compared with the X-ray structure of the oxidized rat mitochondrial isoenzyme and with that of the highly similar bovine microsomal isoenzyme in the oxidized form. The analysis of the elements of secondary structure is instructive in terms of their stability and of their occurrence in related structures, and of the capability of NMR and X-ray spectroscopy to observe them. Some detailed structural variations are noticed among the solved structures of the various isoenzymes and between solid and solution. The structural features in solution of the residues proposed to be involved in protein-protein recognition are found to be largely conserved with respect to the solid state. PMID- 9363780 TI - Methanol:coenzyme M methyltransferase from Methanosarcina barkeri. Zinc dependence and thermodynamics of the methanol:cob(I)alamin methyltransferase reaction. AB - In Methanosarcina barkeri, methanogenesis from methanol is initiated by the formation of methyl-coenzyme M from methanol and coenzyme M. This methyl transfer reaction is catalyzed by two enzymes, designated methyltransferases 1 (MT1) and 2 (MT2). Transferase MT1, which is composed of a 50-kDa subunit, MtaB, and a 27-kDa corrinoid-harbouring subunit, MtaC, has been shown recently to catalyze the methylation of free cob(I)alamin with methanol [Sauer, K., Harms, U. & Thauer, R. K. (1997) Eur. J. Biochem. 243, 670-677]. We report here that this reaction is catalyzed by subunit MtaB overproduced in Escherichia coli. MtaB also catalyzed the formation of methanol from methylcobalamin and H2O, the hydrolysis being associated with a free-energy change deltaG(o)' of approximately +7.0 kJ/mol. MtaB was found to contain 1 mol zinc, and its activity to be zinc dependent (pK(Zn2+) = 9.3). The zinc dependence of the MT2 (MtaA)-catalyzed reaction is also described (pK(Zn2+) = 9.6). PMID- 9363781 TI - The action of alpha-mannosidase from Oerskovia sp. on the mannose-rich O-linked sugar chains of glycoproteins. AB - Alpha-mannosidase was isolated from the culture liquid of Oerskovia sp. The purified enzyme had a molecular mass of 480 kDa and comprises four identical subunits. The enzyme cleaves bonds in side chains of yeast mannan (Km = 0.08 mM, k(cat) = 1.02 micromol x min(-1) x mg(-1)) and reveals a low activity towards p nitrophenyl alpha-D-mannopyranoside. The alpha-mannosidase is a Ca2+-dependent enzyme and is inhibited by EDTA. The enzyme possess no endo-mannosidase activity releasing only mannose in the reaction with the inversion of anomeric configuration and could be classified as exo-alpha-mannanase. The enzyme revealed a high deglycosylating activity towards the short mannose-rich O-linked carbohydrate chains of glycoproteins. PMID- 9363782 TI - Guanine-nucleotide binding and hydrolyzing kinetics of ORrab2, a rice small GTP binding protein expressed in Escherichia coli. AB - The ORrab2 gene encodes a GTP-binding protein of 23.169 kDa. The deduced amino acid sequence shows that ORrab2 has the motifs conserved among small GTP-binding proteins in plants and that it shares sequence identity with Atrab2 (93.0%), Hrab2 (85.2%), Hrab4 (51.9%), Hrab1 (46.2%), YPT (40.7%), Hrab3B (40.0%), Hrab3A (38.1%), SEC4 (38.1%), Hrab5 (34.3%) and Hrab6 (32.4%). To analyze the biochemical properties of this protein, an ORrab2 cDNA was overexpressed in Escherichia coli and the protein purified by Ni2+-nitrilotriacetic acid agarose and hydroxyapatite column chromatography. The molecular mass of the protein bearing a His-tag is approximately 28.2 kDa. The guanine-nucleotide binding and hydrolyzing activity of ORrab2 increased with non-ionic C12E10 (polyoxyethylene 10-lauryl ether) and ionic Chaps detergent treatment. ORrab2 bound maximally 1.03 mol of [gamma-35S]GTP[S]/mol of protein with a Kd value of 56.83 nM. The ratios k(off GDP)/k(off GTP) of ORrab2 were 3.63 for the control, 3.7 in the presence of C12E10, and 3.83 with Chaps, indicating that ORrab2 has a higher affinity for GTP than GDP. The rate (k(cat)) of Pi release against [gamma-32P]GTP bound ORrab2 in a steady state and the rate of hydrolysis of [gamma-32P]GTP (kGTPase) were calculated to be 432 x 10(-4) +/- 8 x 10(-4) min(-1) and 172 x 10(-4) +/- 2 x 10( 4) min(-1), respectively, in the presence of 0.1% C12E10 and 1 mM MgSO4. PMID- 9363783 TI - Fluoresceinyl-ethylenediamine-ouabain detects an acidic environment in the cardiac glycoside binding site of Na+/K+-ATPase. AB - To probe the pH value in the microenvironment of the cardiac glycoside-binding site of Na+/K+-ATPase, pH-sensitive fluorescent derivatives of ouabain were synthesized. The fluoresceinyl derivative of ethylenediamino-ouabain (FEDO) had a pKs of 6.0 and showed a H+-dependent fluorescence change, when its ratio of excitation at 490 nm/450 nm was recorded at 530 nm. Binding of FEDO inactivated Na+/K+-ATPase at 37 degrees C and pH 7.25 in a slow time-dependent process under the conditions of backdoor phosphorylation with k(on) of 891 s(-1) M(-1). The complex dissociated with k(on) of 0.35 x 10(-3) s(-1) resulting in a Kd value of 0.4 microM for the FEDO x enzyme complex. Binding of FEDO was associated with a decrease of the excitatory fluorescence ratio at 490 nm/450 nm which could be used to convert this change into a pH value. A pH value of 5.1 +/- 0.2 was calculated to exist in the microenvironment of the FEDO x enzyme complex. This pH value was independent of the pH of the incubation medium used to form the FEDO x enzyme complex. Analysis of the accessibility of the fluorophore in the FEDO x enzyme complex to the dynamic quencher potassium iodide detected a decrease of the Stern-Volmer constant from 6.2 mM(-1) (free FEDO) to 1.5 mM(-1) (FEDO x enzyme complex) indicating thereby a limited accessibility of the fluorophore to anions. Analysis of the microenvironment of the fluorescein residue of the FEDO x enzyme complex by measurements of the anisotropy and the fluorescence half-life time revealed that both processes differed significantly when H2O was replaced by D2O. We conclude, therefore, that a pH of 5.1 +/- 0.2 exists in the vicinity of ouabain that is hidden in the depth of the receptor site when the ouabain receptor complex has been formed. PMID- 9363785 TI - The TATA-box-binding protein (TBP) of Halobacterium salinarum. Cloning of the tbp gene, heterologous production of TBP and folding of TBP into a native conformation. AB - The TATA-box binding protein (TBP) is a basal transcription factor involved in transcription initiation in Eucarya and Archaea. Using a tbp-specific probe, a 4.5-kbp genomic fragment from Halobacterium salinarum was cloned and sequenced. It contained the tbp gene and the 5'-ends of two additional open reading frames, but surprisingly, 70% of the cloned fragment (3.2 kbp) was devoid of coding capacity or similarity to database sequences. The deduced halobacterial TBP exhibits sequence similarities to other archaeal (41-43%) as well as to eucaryal (27-38%) TBP. A comparative analysis showed that the archaeal and eucaryal TBP form two related monophylic protein families, and the archaeal TBP possess features which separate them from eucaryal TBP. Compared with the other TBP, the halobacterial TBP is unique in having a high excess of negatively charged residues. A histidine-tagged version of the halobacterial TBP was produced in Escherichia coli in a denatured conformation and purified by means of Ni chelating chromatography. CD spectroscopy was used to monitor TBP secondary structure and the conditions necessary for folding it into a native conformation. In the absence of denaturating agents, the folded as well as the unfolded state were found to be stable over a wide range of salt concentrations. Properly folded TBP was shown to bind to a halobacterial TATA-box-containing DNA fragment, indicating that the fusion protein can be used to characterize DNA recognition by the halobacterial TBP. PMID- 9363784 TI - Purification and nucleic-acid-binding properties of a Saccharomyces cerevisiae protein involved in the control of ploidy. AB - Scp160p (Saccharomyces cerevisiae protein involved in the control of ploidy), a polypeptide with a molecular mass of around 160 kDa, is associated with the nuclear envelope and the endoplasmic reticulum. The most noteworthy phenotype of SCP160 deletion mutants is a decrease in viability and an increased number of chromosomes in the surviving cells [Wintersberger, U., Kuhne, C. & Karwan, A. (1995) Yeast 11, 929-944]. Scp160p contains 14 KH domains, conserved motifs that have lately been identified in a variety of RNA-binding proteins. In this report, we demonstrate that the Scp160p sequence shows nearly perfect colinearity with the putative gene product of C08H9.2 from the nematode Caenorhabditis elegans as well as with the vigilins, vertebrate RNA-binding proteins with a cellular location similar to that of Scp160p. Moreover, we found that Scp160p contains a potential nuclear-export signal (NES) near its N-terminus and a potential nuclear localization signal (NLS) between KH domains 3 and 4. To determine whether the protein is able to bind to RNA, we purified Scp160p from yeast cell extract by DNA-cellulose and anti-Scp160p affinity chromatography. In northwestern blotting experiments, the electrophoretically homogeneous protein bound to ribohomopolymers and ribosomal RNA as well as to single-stranded and double stranded DNA. Subcellular fractionation studies revealed that the major part of Scp160p is membrane associated via ionic interactions and can be released from the membrane fraction under conditions that lead to a dissociation of ribosomes. Together, our findings suggest that Scp160p is the yeast homologue of the vigilins, and point to a role for Scp160p in nuclear RNA export or in RNA transport within the cytoplasm. PMID- 9363786 TI - A monoclonal antibody induces opening of a coiled coil. Global protection of amide protons from H/D exchange decreases by up to 1000-fold in antibody-bound triple-stranded coiled coil. AB - Antibody specificity is limited, and different antigens may cross-react to varying degrees with the same antibody. An example is monoclonal antibody 42PF elicited against a 29-residue random-coil peptide. 42PF cross-reacts with a triple-stranded coiled coil of related amino acid sequence, and there was circumstantial evidence for an antibody-induced opening of the coiled coil [Leder, L., Berger, C., Bornhauser, S., Wendt, H., Ackermann, F., Jelesarov, I. & Bosshard, H. R. (1995) Biochemistry 34, 16,509-16,518]. To reveal in a direct way that antibody 42PF induces the opening of the coiled coil, we have compared the rates of H/D exchange of amide protons in the free and in the antibody-bound coiled-coil peptide using electrospray-ionization mass spectrometry for the analysis of deuterium incorporation. Complete H/D exchange lasted several days in the tightly folded coiled-coil conformation while in the presence of antibody 42PF the overall exchange took only minutes, corresponding to a thousand-fold decrease of protection of the most slowly exchanging amide hydrogens of the folded coiled coil. This demonstrates that the antibody induced a considerable opening of the coiled coil. PMID- 9363787 TI - Rescue of a mutant G-protein by substrate-assisted catalysis. AB - Signaling by guanine-nucleotide-binding proteins (G-proteins) occurs when they are charged with GTP, while hydrolysis of the bound nucleotide turns the signaling off. Despite a wealth of biochemical and structural information, the mechanism of GTP hydrolysis by G-proteins remains controversial. We have employed substrate-assisted catalysis as a novel approach to study catalysis by G proteins. In these studies, we have used diaminobenzophenone-phosphonoamidate GTP, a unique GTP analog bearing the functional groups that are missing in the GTPase-deficient [Leu227]G(s alpha) mutant. This mutant, found in various human tumors, fails to hydrolyze GTP for an extended period. In contrast, the GTP analog is hydrolyzed by this mutant and by the wild-type enzyme at the same rate. On the other hand, modification of G(s alpha) by cholera toxin, which catalyses ADP-ribosylation of Arg201 of G(s alpha), decreased the rates of hydrolysis of both GTP and its analog by 95%. These results attest to the specificity of the GTP analog as a unique substrate for the [Leu227]G(s alpha) mutant and to the essential role of Gln227 in GTP hydrolysis. Furthermore, the finding that the GTP analog was hydrolyzed at the same rate as GTP by the wild-type enzyme, favors a model in which formation of a pentavalent transition state intermediate, presumably stabilized by the catalytic glutamine, is not the rate-limiting step of the GTPase reaction. PMID- 9363788 TI - Expression, reconstitution and characterization of prolixin-S as a vasodilator--a salivary gland nitric-oxide-binding hemoprotein of Rhodnius prolixus. AB - Prolixin-S, an anticoagulant from the salivary gland of the blood-sucking insect Rhodnius prolixus is also one of the members of salivary gland hemoproteins. We produced recombinant protein using a baculovirus-insect cell expression system, reconstituted the hemoprotein and made some characterization of it as a nitric oxide carrier. The reconstituted protein exhibited the absorption spectrum of a high-spin ferric hemoprotein with a Soret absorption peak at 400 nm. By binding nitric oxide (NO-prolixin-S), the Soret band shifted from 400 nm to 420 nm and two sharp bands (Q bands, at 535 nm and 565 nm) also appeared in the visible region. In a bioassay with aortic smooth muscle, NO-prolixin-S showed strong relaxation activity in a dose-dependent manner, which demonstrated that prolixin S really acts as an NO carrier. A Soret absorption change also indicated that nitric oxide was gradually released under these conditions (pH 7.4 and 37 degrees C). However, at low temperature (20 degrees C) and/or low pH (pH 6), which mimic those in the insect's salivary glands, the releasing became very slow. These different NO-binding properties would enable prolixin-S to reserve nitric oxide in the salivary glands and release it in the host's blood vessels. PMID- 9363789 TI - Identification and analysis of a static culture-specific cell wall protein, Tir1p/Srp1p in Saccharomyces cerevisiae. AB - A 100-kDa protein was found to be a major cell wall protein in Saccharomyces cerevisiae cells cultured without shaking, but was not present in cells cultured with shaking. The amino acid sequence of this protein was identical to the sequence of Tir1p/Srp1p. TIR1/SRP1 has previously been identified as a gene induced by glucose, cold shock or anaerobiosis and was believed to be a cell membrane protein but not a cell wall protein. However, we found that beta-1,3 glucanase solubilized Tir1p/Srp1p from the cell wall and the purified Tir1p/Srp1p reacted with antiserum to beta-1,6-glucan and contained glucose. These results suggest that Tir1p/Srp1p is a major structural cell wall protein in the static cultured yeast cells and is bound to the cell wall through beta-1,6-glucan. TIR1/SRP1 mRNA was transcribed only in the static culture and its transcription was regulated by the ROX1 repressor. PMID- 9363790 TI - Cell respiration is controlled by ATP, an allosteric inhibitor of cytochrome-c oxidase. AB - The activity of cytochrome-c oxidase, the terminal enzyme of the mitochondrial respiratory chain, is known to be regulated by the substrate pressure, i.e. the ferro-/ferricytochrome c ratio, by the oxygen concentration, and by the electrochemical proton gradient delta muH+ across the inner mitochondrial membrane. Here we describe a further mechanism of 'respiratory control' via allosteric inhibition of cytochrome-c oxidase by ATP, which binds to the matrix domain, of subunit IV. The cooperativity between cytochrome-c-binding sites in the dimeric enzyme complex is mediated by cardiolipin, which is essential for cooperativity of the enzyme within the lipid membrane. PMID- 9363791 TI - 8OHdG levels in brain do not indicate oxidative DNA damage in Alzheimer's disease. AB - Accumulation of oxidative DNA damage has been proposed to underlie aging and neurodegenerative diseases such as Alzheimer's Disease (AD). The DNA adduct 8 hydroxy-2'-deoxyguanosine (8OHdG) is considered a good indicator of oxidative DNA damage. To investigate whether this type of DNA damage is involved in AD etiology, 8OHdG levels were determined in postmortem human brain tissue of controls and AD patients (in frontal, occipital, and temporal cortex and in hippocampal tissue). Parametric studies in rat revealed no influences of postmortem delay, repeated freezing/thawing or storage time. In human brain, approximately two 8OHdG molecules were present per 10(5) 2'-deoxyguanosines. In AD patients and controls, 8OHdG-levels were not related to age, sex, or brain region. Also, no differences were found between controls and AD patients. It was concluded that 8OHdG in nuclear DNA, although present throughout the brain in fairly high amounts, does not accumulate with age, nor does it appear to be involved in AD. More detailed studies are required to extend this conclusion to other types of oxidative damage. PMID- 9363792 TI - Mitochondrial DNA deletions are rare in the free radical-rich retinal environment. AB - We measured the levels of a somatic, 4977 bp deletion of mitochondrial DNA (mtDNA4977) in paired neural retinal and optic nerve tissues from 14 adults and 1 infant using a quantitative PCR assay. MtDNA is prone to free radical damage, and areas in the brain that are exposed to high levels of free radicals are observed to accumulate higher levels of the mtDNA4977 deletion. The levels of mtDNA deletions also increase with age in many tissues. Despite the presence of a free radical rich environment, mtDNA from the neural retina possessed extremely low mtDNA4977 levels (0.0001-0.001%). Deletion levels were always lower than those in the optic nerve from the same eye and do not appear to increase with age. Our results suggest that antioxidant defenses in the neural retina are effective in protecting mtDNA against oxidative damage. PMID- 9363793 TI - Aging is associated with divergent effects on Nf-L and GFAP transcription in rat brain. AB - We studied the effects of advancing age on the expression of several proteins important in the structure and function of the nervous system. Brains of young (3 month), middle-aged (13 month), and old (29 month) male Fischer 344 rats were examined. Run-on transcription and Northern blot hybridizations were used to determine gene-specific transcription rates and mRNA levels, respectively. With advancing age, there was a decrement in the transcription rate and mRNA levels for neurofilament-light subunit (Nf-L), but an increment in the transcription rate and mRNA levels for glial fibrillary acidic protein (GFAP). Proteolipid protein (PLP) mRNA levels were attenuated between 3 and 13 months of age, whereas amyloid precursor protein (APP) mRNA levels were attenuated in the middle-aged but not the old animals. Transcription rates for alpha-actin and fos, and mRNA levels for alpha-actin, were unaffected. These observations indicate divergent transcriptional regulation of several genes, notably Nf-L and GFAP, in the aging mammalian forebrain. PMID- 9363794 TI - Cytochrome c oxidase defects of the human substantia nigra in normal aging. AB - Based on morphological, biochemical, and molecular biologic analyses, degeneration of the dopaminergic nigrostriatal system has been reported to occur with normal aging. In the present study, the substantia nigra of 36 human brains with normal aging was investigated by means of morphometry and immunohistochemistry. The anteromedial (Am), anterointermediolateral (Ail), posteromedial (Pm), and posterolateral (Pl) nuclei of the substantia nigra were analyzed using antibodies directed against the subunits II/III of cytochrome c oxidase (COX), the complex IV of the respiratory chain. The numerical density of melanin-positive neurons with COX defects was significantly increased in the four investigated nuclei, namely Am, Ail, Pm, and Pl. These cells did not show any histologic signs of degeneration. The numerical density of melanin-positive neurons without COX defects was decreased with aging. The data of the present study indicate that complex IV defects of neurons in the substantia nigra might be one cause of neuronal dysfunction occurring during aging. PMID- 9363795 TI - Effect of TAK-147, a novel AChE inhibitor, on cerebral energy metabolism. AB - Effect of TAK-147, a novel acetylcholinesterase (AChE) inhibitor, on cerebral energy metabolism was investigated using an in vivo 31P-magnetic resonance spectroscopy (31P-MRS) technique and the autoradiographic 2-deoxy-[14C]-D-glucose method in aged Fischer 344 rats. We revealed that high-energy phosphate metabolites, phosphocreatine (PCr) and ATP, in the brain decreased gradually with aging and that significant decrement of cerebral PCr and ATP was observed from 13 and 8.5-month-old in comparison with those of 2.5-month-old rats, respectively. Daily oral administration of TAK-147 (1 mg/kg) for 40 days increased PCr and ATP levels in aged rats (29-month-old). To determine the site at which TAK-147 acts to increase high-energy phosphate metabolism, we investigated the rate of local cerebral glucose utilization (LCGU) in various brain regions. The rate of LCGU decreased in almost all brain regions in aged rats (28 months of age), and the decrease was significant in 29 out of the 35 regions. When TAK-147 was administered orally to the aged rats, the levels were dose dependently increased, especially in the auditory cortex. These results indicate that TAK-147 increases cerebral energy metabolism in aged rats. PMID- 9363797 TI - Binding of platelet-activating factor to platelets of Alzheimer's disease and multiinfarct dementia patients. AB - The binding of 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine (platelet activating factor, PAF) to platelets was studied in 22 patients with probable Alzheimer's disease (AD), 11 with multi-infarct dementia (MID), 22 age-matched normal old controls, and 20 young subjects. The results showed a significantly lower degree of PAF binding to platelets of AD and MID patients than in those of the old controls and young subjects (133.3 +/- 8.5, and 123.4 +/- 16.5 vs. 202.3 +/- 11.6 and 206.7 +/- 17.3 receptors/cell, respectively; p < 0.01). These differences were due to reduced Bmax, while Kd remained unchanged. No significant difference was observed between the PAF binding to platelets of AD and MID patients nor between that of old and young controls. No correlation was found between age and binding in the various elderly groups. However, a significant correlation was found between PAF binding and degree of cognitive impairment in the AD patients. This is the first evidence to support a possible involvement of PAF in dementing disorders. PMID- 9363796 TI - Stress-induced changes in brain-derived neurotrophic factor expression are attenuated in aged Fischer 344/N rats. AB - Aging and stress can sometimes result in a decline in brain function. We addressed the question whether changes in the expression of neurotrophic factors, which are necessary for the survival and maintenance of neurons, might occur during aging and stress. Therefore, we used in situ hybridization to investigate the effects of aging and stress on neurotrophic factor expression in young (3-4 month) and old (24 month) male Fischer 344/N rats. The ability of acute immobilization stress (2 h) to modulate BDNF mRNA levels in old rats was significantly reduced both in the hippocampus (a smaller decrease in BDNF) and the PVN (a smaller increase in BDNF) compared to young rats. In contrast, the induction of nerve growth factor and neurotrophin 3 (NT-3) by stress was not influenced by age. The diminished BDNF responses to stress in aged rats may be relevant to difficulties in adaptation to stress encountered during old age. PMID- 9363798 TI - The lipid compositions of different regions of rat brain during development and aging. AB - The lipid contents in different regions of the rat brain were analyzed from birth to the age of 2 years. The total brain phospholipid content increased threefold during the first 20 postnatal days. The cholesterol content elevated extensively during the first 2 months of life and, after this period, remained unchanged. The level of dolichol increased almost 100-fold during the first 10 months of life and continued to increase thereafter. Some modifications in the dolichol isoprenoid pattern were also observed. An increase in the brain ubiquinone level occurred during the first few months of life, but no further change was observed after this period. Ubiquinone-9 and -10 constituted 70 and 30%, respectively, of the total ubiquinone in all regions and all subcellular fractions. The alpha tocopherol content increased during the first 3 weeks of life and was unchanged thereafter. These results demonstrate characteristic changes in the lipid contents of various regions of rat brain during development and aging. PMID- 9363799 TI - Decline in striatal dopamine D1 and D2 receptor activation in aged F344 rats. AB - Aging differentially affects receptor function. In the present electrophysiological study we compared neuronal responsiveness to locally applied dopamine D1 and D2 receptor agonist in the striatum of female Fischer 344 rats aged 3 and 26-27 months. In a subgroup of the old rats, the nigrostriatal dopamine bundle was destroyed unilaterally with 6-hydroxydopamine (6-OHDA) to assess receptor plasticity in response to denervation. Spontaneous firing rate of striatal neurons was higher in aged compared to young rats. Higher doses of the D1 agonist SKF 38393 or the D2 agonist quinpirole were required to elicit a 50% change in firing rate in aged compared to young rats. No difference with SKF 38393 or quinpirole was detected between 6-OHDA denervated and control (nonlesioned) striatum in aged rats. Supersensitivity to D2 agonists has been reported following 6-OHDA lesions in young rats. These observations suggest that D2 receptors in aged rat striatum might not be as plastic as in younger rats. PMID- 9363800 TI - Advancing age alters intracellular calcium buffering in rat adrenergic nerves. AB - There is a marked increase with advancing age of stimulation-evoked neurotransmitter release from vascular adrenergic nerves in the rat, an effect correlated with increased levels of plasma norepinephrine. This increase in norepinephrine release could not be accounted for by an alteration in neuronal and extraneuronal uptake of norepinephrine or a decline in feedback inhibition of release by prejunctional alpha2-adrenergic receptors. Measurement of intracellular calcium in fura-2-labeled superior cervical ganglion cells revealed elevated K+-evoked calcium transients in old compared to young neurons. Blockade of mitochondrial calcium uptake with dinitrophenol resulted in increased calcium transients in old neurons only. Furthermore, following blockade of mitochondrial calcium uptake the rate of return of calcium to resting levels was reduced to a greater degree in old cells as compared to young cells. The effects of dinitrophenol in old cells were attenuated when extracellular calcium was reduced. These findings suggest that older cells are more dependent on mitochondrial calcium buffering, perhaps due to changes in ATP dependent calcium uptake. Increased calcium transients as a result of altered intracellular calcium buffering offer a reasonable explanation for our previous observation of increased stimulation evoked norepinephrine release. PMID- 9363801 TI - Local and distant histopathological effects of unilateral amyloid-beta 25-35 injections into the amygdala of young F344 rats. AB - To determine if amyloid-beta (A beta) induces tau-immunoreactivity (IR) and reactive astrocytosis in vivo, we injected A beta 25-35 (5.0 nmol) into the right amygdala of rats. At 8 days postinjection, the peptide induced tau-2 IR in neuronal cell bodies and processes ipsilaterally in the amygdala, cingulate cortex, and hippocampus. At 32 days postinjection, the intensity of tau-2 IR was greater than at 8 days in the amygdala and hippocampus, but not in the cingulate cortex. Induction of Alz-50 IR also was progressive but the morphology and distribution was different from tau-2 IR. Beaded fibers with occasional neuronal perikarya were visualized with Alz-50, and the IR was primarily observed in the ipsilateral amygdala. In addition, amygdaloid injections of A beta 25-35 induced reactive astrocytosis, particularly in the ipsilateral hippocampus at 32 days postoperatively. To our knowledge, this is the first study to show that in vivo injections of A beta 25-35 induce progressive transsynaptic cytoskeletal and astrogliotic reactions, that gradually spread from the area of injection to brain regions that have prominent efferent connections with that area. These findings also suggest a direct association between plaque and tangle formation in Alzheimer's disease. PMID- 9363802 TI - A beta40 is a major form of beta-amyloid in nonhuman primates. AB - Because aged nonhuman primates show beta-amyloid (A beta) deposition in senile plaques and blood vessels similar to that seen in human aging and AD, we used C terminal specific antibodies to A beta40 and A beta42 to investigate A beta peptide length in the brains of 11 aged rhesus monkeys and a 59-year-old chimpanzee. In contrast to AD, where the earliest and most prominent form of A beta in senile plaques is A beta42, in the monkey, A beta40-positive plaques predominated. The ratio of A beta40:A beta42-positive plaques averaged 2.08 in the monkey, as compared to a mean ratio of 0.37 in 68 human AD subjects (p < 0.001). A beta40 was also more prominent in the chimpanzee than in humans. Possible explanations for these findings include species differences in the cleavage of A beta from the amyloid precursor protein or in the activity of a putative carboxy peptidase forming A beta40 from A beta42 in situ. PMID- 9363803 TI - Neurofibrillary pathology--correlation with hippocampal formation atrophy in Alzheimer disease. AB - The three-dimensionally reconstructed hippocampal formations in three patients with very severe, immobile Alzheimer disease (AD) and three age-matched nondemented individuals were examined for a correlation between atrophy of hippocampal formation subdivisions and neurofibrillary changes, neuronal loss, and extent of amyloid deposition in plaques and vessels. In AD, a similar severe volume loss was observed in both cellular layers and layers composed of fibers. A strong correlation between the decrease in the volume of hippocampal formation subdivisions and the decrease in the total number of neurons suggests a causative role for neuronal loss in hippocampal formation volumetric loss. Strong regional correlations between the relative decreases in the total number of neurons and the relative increases in the total number of neurofibrillary tangles implicates neurofibrillary pathology as a possible etiologic proximate factor in neuronal and volumetric loss in the hippocampal formation of AD patients. PMID- 9363804 TI - Beta-amyloid deposition and other measures of neuropathology predict cognitive status in Alzheimer's disease. AB - The relationship between progressive cognitive decline and underlying neuropathology associated with Alzheimer s disease (AD) is a key issue in defining the mechanisms responsible for functional loss. This has been a subject of much controversy, with separate studies comparing various clinical and neuropathological indices in AD. Further, it is difficult to compare studies with differences in histochemical staining protocols, brain regions examined, and data quantification criteria. There are many difficulties in designing a clinical pathological correlative study involving AD patients. It is necessary to control for several key parameters. For example, a broad range of cognitively impaired subjects is needed, as well as short postmortem delays, brief intervals between cognitive testing and death, and the most sensitive detection and quantification techniques. In this study, we carefully controlled for each of these parameters to determine if there is a relationship between global cognitive dysfunction and multiple neuropathological indices. We selected 20 individuals representing a broad range of cognitive ability from normal to severely impaired based on the MMSE, Blessed IMC, and CDR. We counted plaque number, NFT number, dystrophic neurite number, and the relative extent of thioflavine positive plaques and neuritic involvement within plaques. We also quantified cortical area occupied by beta-amyloid immunoreactivity (A beta Load) and PHF-1 positive neuropil threads and tangles (PHF Load) using computer-based image analysis. Interestingly, we found that most pathologic measures correlated highly with the severity of dementia. However, the strongest predictor of premortem cognitive dysfunction on all three cognitive measures was the relative area of entorhinal cortex occupied by beta-amyloid deposition. In conclusion, our data show that in a carefully controlled correlative study, a variety of neuropathological variables are strongly correlated with cognitive impairment. Plaque related variables may be as strongly related to cognitive dysfunction as other established measures, including synapse loss, cell death and tau hyperphosphorylation, although no correlative study can demonstrate causality. PMID- 9363805 TI - Disentangling a complex pattern of interrelationships among multiple measures of Alzheimer neuropathology and clinical status: comments on Cummings, Pike, Shankle, and Cotman. PMID- 9363806 TI - Senile cerebral amyloidosis (pathological aging) and cognitive status predictions: a neuropathology perspective. PMID- 9363808 TI - Neuropathological markers of impaired cognition in the entorhinal cortex. PMID- 9363807 TI - Alzheimer's disease pathogenesis: the challenge of establishing dynamic biological processes from static measurements. PMID- 9363809 TI - The cellular and molecular correlates of cognitive impairments in the Alzheimer's disease brain. PMID- 9363810 TI - On keys and correlations in Alzheimer's disease. PMID- 9363812 TI - Is syncope the same thing as sudden death except that you wake up? PMID- 9363811 TI - Implantable cardioverter defibrillator utilization among device recipients presenting exclusively with syncope or near-syncope. AB - INTRODUCTION: Implantable cardioverter defibrillators (ICDs) are occasionally used in presumed high-risk patients with electrocardiographically undocumented syncope, although the incidence of ventricular tachyarrhythmias in this population is not well defined. METHODS AND RESULTS: We studied 33 consecutive patients receiving an ICD (67% nonthoracotomy and 70% tiered therapy) after electrophysiologic testing for unmonitored "syncope" (n = 29) or "near-syncope" (n = 4). Atherosclerotic heart disease was present in 24 (73%); mean left ventricular ejection fraction (LVEF) was 0.39 +/- 0.15; and sustained monomorphic ventricular tachycardia (SMVT) was inducible in 18 (55%). Over a median follow-up of 17 months (range 4 to 61), 12 patients (36%) received > or = 1 appropriate ICD discharge triggered by SMVT (cycle length 230 to 375 msec) in 10 and ventricular flutter or fibrillation in 2--without concomitant antiarrhythmic medication in 8 of 12 cases. Inducible SMVT and LVEF < or = 0.35 were statistically significant, independent predictors of an appropriate ICD discharge (P < 0.02 and P < 0.03, respectively). Estimated 1-year cumulative survival free of appropriate discharge was 34% versus 87%, respectively, in patients with versus without inducible SMVT (P < 0.02), and 18% versus 56%, respectively, in patients with LVEF < or = 0.35 versus LVEF > 0.35 (P < 0.03). CONCLUSION: In this highly select, multicenter population of ICD recipients with electrocardiographically undocumented syncope, a substantial incidence of appropriate device discharges was observed, particularly in patients with inducible SMVT and LVEF < or = 0.35. These findings support the notion that, in patients with LV dysfunction and inducible SMVT, ventricular tachyarrhythmias are likely to account for episodes of syncope or near-syncope. PMID- 9363813 TI - Influence of epinephrine, propranolol, and atrial pacing on spatial distribution of recovery time measured by body surface mapping in congenital long QT syndrome. AB - INTRODUCTION: Sympathetic stimulation plays an important role in the genesis of QT(U) prolongation and ventricular arrhythmias in congenital long QT syndrome (LQTS). Permanent pacemaker as well as beta blockers are reported to be effective in the management of this syndrome. The purpose of this study was to examine influence of epinephrine (alpha- and beta-adrenergic stimulation), propranolol (beta blocker), and atrial pacing on the spatial distribution of repolarization using body surface recovery time (RT) in congenital LQTS. METHODS AND RESULTS: Body surface mapping was recorded in 16 patients with congenital LQTS and 20 control patients before and after epinephrine infusion (0.1 microg/kg per min), oral propranolol (1 to 2 mg/kg per day), addition of epinephrine during oral propranolol, atrial pacing at a cycle length of 600 or 750 msec, and addition of epinephrine during atrial pacing. The RT, that is, the interval between the QRS onset and the maximum dV/dt point in the ST-T segment, was measured automatically by a computer from each of the 87 mapping leads, and the corrected RT (RTc) was calculated using Bazett's method. In patients with congenital LQTS, epinephrine markedly changed the T(U) wave morphology and spatial distribution of RT, especially the distribution of maximum RT of the left anterior chest and back. Epinephrine prolonged the maximum RTc and the minimum RTc in 87 leads and increased the RTc dispersion (difference between maximum and minimum RTc in each patient). Neither propranolol nor atrial pacing changed the T(U) wave morphology, spatial distribution of RT, or any RTc parameters at rest. Propranolol prevented the influences of epinephrine on the T(U) wave morphology, spatial distribution of RT, and RTc parameters, whereas atrial pacing did not. In control patients, marked changes of the T(U) wave morphology and RTc parameters were not recognized during the entire protocol. CONCLUSIONS: Our results indicate that epinephrine markedly changes the spatial distribution of repolarization and increases the dispersion of repolarization, which probably are linked to arrhythmogenesis in congenital LQTS. The data suggest that propranolol but not atrial pacing are effective to suppress repolarization abnormalities during sympathetic stimulation. PMID- 9363814 TI - Mode of onset of malignant ventricular arrhythmias in idiopathic ventricular fibrillation. AB - INTRODUCTION: The mode of onset of malignant ventricular arrhythmias (ventricular tachycardia [VT] or ventricular fibrillation [VF]) has been well described in patients with organic heart disease and in patients with the long QT syndromes. Less is known about the mode of onset of VF in patients with out-of-hospital VF who have no evidence of organic heart disease or identifiable etiology. METHODS AND RESULTS: We reviewed the ECGs of all our patients with idiopathic VF. Documentation of the onset of spontaneous arrhythmias was available for 22 VF episodes in 9 patients (6 men and 3 women; age 41 +/- 16 years). In all instances, spontaneous VF followed a rapid polymorphic VT, which was initiated by premature ventricular complexes (PVCs) with very short coupling intervals. The PVC initiating VF had a coupling interval of 302 +/- 52 msec and a prematurity index of 0.4 +/- 0.07. These PVCs occurred within 40 msec of the peak of the preceding T wave. Pause-dependent arrhythmias were never observed. CONCLUSION: Cardiac arrest among patients with idiopathic VF has a very distinctive mode of onset. Documentation of a polymorphic VT that is not pause dependent is of diagnostic value. PMID- 9363815 TI - Use of only a regular diagnostic His-bundle catheter for both fast and reproducible "para-Hisian pacing" and stable right ventricular pacing. AB - INTRODUCTION: Para-Hisian pacing, i.e., pacing the anteroseptal right ventricle (RV) with or without direct capture of the His bundle (HB), allows the differentiation of VA conduction over the AV node from conduction over an accessory pathway. Classically, it is performed by maneuvering a separate pacing catheter around the HB catheter, which may be difficult and time-consuming. METHODS AND RESULTS: This study prospectively evaluated the use of a single standard octapolar HB catheter with 2-mm interelectrode spacing for simultaneous (para-Hisian) pacing from the distal bipole and recording from the three proximal bipoles in 148 consecutive patients. Para-Hisian pacing was successful in 146 of 148 patients, performed within a median of only 10 seconds, and easily repeated several times during the course of an electrophysiologic study. Retrograde HB activation could be recorded in 132 of 146 patients; a clearly different surface ECG configuration confirmed the presence or absence of HB capture in all other patients. Interestingly, stable RV pacing could be performed from the HB catheter for the rest of the electrophysiologic study in 138 of 142 patients in whom this was tried. RV pacing from this site also led to better interpretation of retrograde conduction, due to clear visualization of retrograde HB activation. CONCLUSION: Pacing from the distal bipole of a regular diagnostic HB catheter provides a fast and reliable way to perform para-Hisian pacing. Therefore, it may be advocated as a routine diagnostic protocol during electrophysiologic procedures. Moreover, pacing from this site obviates the need for a separate RV pacing catheter in most patients. PMID- 9363816 TI - Relation of the atrial input sites to the dual atrioventricular nodal pathways: crossing of conduction curves generated with posterior and anterior pacing. AB - INTRODUCTION: The usually accepted definition of the dual pathway electrophysiology requires the presence of conduction curves with a discontinuity ("jump"). However, AV nodal reentrant tachycardia has been observed in patients with "smooth" conduction curves, whereas discontinuity of the conduction curve does not guarantee induction of stable reentry. We hypothesize that the duality of AV nodal conduction can be revealed by careful choice of stimulation sites during the generation of AV nodal conduction curves. METHODS AND RESULTS: In 21 rabbit heart atrial-AV nodal preparations, programmed electrical stimulation with S1-S2-S3 pacing protocol was applied either posteriorly at the crista terminalis input site (CrT) or anteriorly at the lower interatrial septum input site (IAS), or (in 8 preparations with surgically divided input sites) at both. We found that in intact preparations with "smooth" conduction curves, pacing at long coupling intervals produced shorter AV nodal conduction times from the IAS (56 +/- 9.8 msec vs 69 +/- 10.1 msec; P < 0.01). At short coupling intervals, in contrast, shorter conduction times were obtained from the CrT (173 +/- 21.8 msec vs 188 +/- 22.8 msec; P < 0.01). This resulted in a characteristic crossing of the superimposed IAS and CrT conduction curves. After division of the inputs, the IAS site had rapid conduction to the His bundle but a longer refractory period, whereas the CrT site had long conduction times and shorter refractory periods. Wavefronts entering the AV node from these two inputs can summate, resulting in improved conduction. CONCLUSION: Pacing protocols designed to accentuate the asymmetry between the AV nodal inputs can help to reveal the functional difference between the dual pathways and thus to better assess the properties of AV nodal conduction. PMID- 9363817 TI - Redefining dual AV nodal physiology. PMID- 9363818 TI - Electrophysiologic features of torsades de pointes: insights from a new isolated rabbit heart model. AB - INTRODUCTION: The exact electrophysiologic mechanism of torsades de pointes (TdP) is under intense investigation. No isolated animal heart model of this particular arrhythmia exists. METHODS AND RESULTS: In isolated rabbit hearts, TdP was induced by means of bradycardia in the presence of a high concentration of d sotalol (10(-4) M) and shortly after lowering the concentration of potassium and magnesium in the perfusate. Multiple simultaneous epicardial and endocardial monophasic action potentials (MAPs) and volume-conducted 12-lead ECGs were recorded. d-Sotalol prolonged repolarization and increased dispersion of ventricular repolarization compared to baseline recordings. With the onset of low potassium and magnesium concentrations, repolarization was further prolonged and dispersion of repolarization was further increased followed by the occurrence of early afterdepolarizations (EADs) in the majority of MAP recordings, i.e., at both endocardial and epicardial locations of both ventricles. Upon increase of EAD amplitude, triggered arrhythmias with TdP of up to 42 beats ensued in 10 of 11 hearts studied. MAP duration at 90% repolarization (APD90), dispersion of APD90, and the incidence of EADs as well as dispersion of the QT interval and T wave area were significantly higher in beats triggering bigemini, couplets, or runs of TdP. CONCLUSION: TdP observed in this new isolated heart model was associated with markedly increased dispersion of ventricular repolarization and the occurrence of EADs in multiple locations of the heart. TdP is initiated when the amplitude of an EAD reaches threshold for initiation of the first beat of an episode. PMID- 9363819 TI - Animal models of the long QT syndrome: relation to clinical features. PMID- 9363820 TI - Ablation of ventricular tachycardia due to a postinfarct ventricular septal defect: identification and transection of a broad reentry loop. AB - INTRODUCTION: Ventricular tachycardia (VT) after postinfarct ventricular septal defect (VSD) repair has not been well characterized. METHODS AND RESULTS: A 55 year-old man developed refractory VT after inferior wall infarction and VSD repair. Entrainment demonstrated a broad reentry circuit path (outer loop) between the tricuspid annulus and VSD patch. A series of radiofrequency (RF) lesions transected this path, abolishing VT and producing conduction block between the inferior and superior aspects of the basal right ventricular septum. CONCLUSION: Some VTs have broad reentry loops requiring ablation by a series of RF lesions across the path to create a line of block. This approach is analogous to that for atrial flutter. PMID- 9363821 TI - Inappropriate discharge of an implantable cardioverter defibrillator during atrial flutter and intermittent ventricular antibradycardia pacing. AB - INTRODUCTION: Inappropriate discharges of an implantable cardioverter defibrillator (ICD) are troublesome to the patient and sometimes a difficult task for the physician trying to identify and treat the cause. METHODS AND RESULTS: For the first time, we report a mechanism of inappropriate ICD discharges during episodes of atrial flutter with a slow ventricular response and intermittent antibradycardia pacing. The episodes occurred in two patients and were triggered by the unique sensing algorithm of the Ventritex Cadence V-100 in combination with the tripolar CPI Endotak 072 transvenous defibrillation lead, which provides integrated bipolar sensing. CONCLUSION: Besides treatment of the underlying arrhythmia, reprogramming of the device, an electrode position far away from the atria, and true bipolar sensing will enhance the performance of ICD systems with respect to the episodes described here. In addition, more flexible sensing algorithms may, in the future, prevent this overall rare complication. PMID- 9363822 TI - Antiarrhythmic drug therapy in the management of atrial fibrillation. AB - Antiarrhythmic drugs have been used for the acute conversion of atrial fibrillation to sinus rhythm, as well as for the long-term maintenance of sinus rhythm. In recent years, concerns regarding antiarrhythmic drug efficacy as well as safety have prompted a re-examination of the indications for antiarrhythmic therapy in patients with atrial fibrillation. This review will focus on the safety and efficacy of antiarrhythmic therapy in the acute and chronic management of patients with atrial fibrillation. PMID- 9363823 TI - Newer clinical applications of pacing. AB - For many years, the indications for permanent cardiac pacing consisted primarily of AV block and sinus node dysfunction. In recent years, the indications for pacing have expanded considerably. This article details recent advances in the application of permanent pacing and the use of permanent pacing for patients with hypertrophic cardiomyopathy, dilated cardiomyopathy, prevention of atrial fibrillation, and pacing in the long QT syndrome. Pacing is now an accepted therapeutic modality in hypertrophic cardiomyopathy and has rapidly gained acceptance in the United States, although there are still many unknowns about selection of patients and long-term benefits. Even less is known about pacing for dilated cardiomyopathy. Certain patients do respond with definite subjective improvement and improved quality of life, although there are no data to date to suggest improved longevity. Pacing for long QT syndrome is now a well-accepted indication for this relatively small subset of patients. Pacing for the prevention of atrial fibrillation is still in the very early stages of development. Multiple methods have been tried with the current method of choice being dual site atrial pacing. However, it is too early to predict the long-term success of this modality. PMID- 9363824 TI - A wide QRS complex, long RP tachycardia: what is the tachycardia mechanism? PMID- 9363825 TI - The bipolar pacing threshold of the right ventricle before and after biphasic waveform ventricular defibrillation shocks in 67 patients. PMID- 9363826 TI - Acute ischemic stroke therapy. A clinical overview. AB - Acute ischemic stroke therapy has two basic therapies, dissolving the intravascular occlusion by thrombolytic therapy and protecting the brain from the harmfull cellular, and metabolic consequences ofischemic injury by neuroprotective therapy. It seems most likely that the methods that will be used to treat the acute ischemic stroke patient will be multiple, likely a combination of thrombolytic therapy for early reperfusion and neuroprotective therapy for maintaining vitality. In the last decade, a number of advances in the field of imaging and pharmacology have been made which should provide meaningful improvement for the management of acute ischemic stroke patients in the near future. This update summarizes recent clinical trials and emphasizes the question of risk versus benefit for the acute ischemic stroke therapies being developed. PMID- 9363827 TI - Acute and critical care in neurology. AB - The diagnostic and therapeutic management of selected neurological diseases requiring intensive treatment is summarized with special regard for current standards and new developments in therapy. Ischemic stroke is an emergency since the outcome can be improved by immediate and adequate general supporting as well as specific (thrombolytic) therapy in specialized stroke units. Surgical evacuation of supratentorial intracerebral hemorrhage is still controversial. We give an overview of conditions in which surgical therapy such as cerebellar hemorrhage and large, nondominant ganglionic hemorrhage might be advisable. Cerebral venous thrombosis is treated with full-dose intravenous heparin even if hemorrhage is present. In acute bacterial meningitis, early treatment of foci and empiric antibiotic therapy is crucial in order to prevent complications. The outcome of herpes simplex encephalitis can be favorably influenced by treatment with aciclovir and aggressive therapy of elevated ICP and seizures. Acute Guillain-Barre syndrome requires daily monitoring of vital functions in order to recognize the need for intensive care; intravenous immunoglobulins and plasmapheresis are equally recommended for clinical and financial reasons. PMID- 9363828 TI - Emerging treatments in headache. AB - Recent PET studies performed in humans during migraine attacks revealed a 'spreading depression-like' oligemia in the occipital cortex during the aura phase and a region of increased blood flow in the brainstem during the headache phase. Animal models were established to test new migraine drugs. A number of 5 HT agonists, the so-called 'triptans', will be available in future besides sumatriptan to treat acute migraine attacks. Migraine prophylaxis is still hampered by the fact that we do not understand the action of drugs used for this purpose and do not have an animal model. Nevertheless, new substances were introduced recently into the prophylaxis of migraine. PMID- 9363829 TI - Emerging treatments in Parkinson's disease. AB - This paper provides a critical review on the most recent developments in the treatment of Parkinson's disease. New symptomatic therapies include the use of catechol-O-methyltransferase (COMT) inhibitors, new dopamine agonists and of surgical treatments (such as pallidotomy or deep brain stimulation). Protective strategies include the use of COMT and monoamine oxidase B inhibitors, of dopamine agonists and of trophic factors. The main preclinical premises, on which the usage of newly developed therapies is based, are discussed. Symptomatic therapy has been greatly refined in recent years and has gradually become a polytherapeutic approach. Protective therapy, which will attract the interest of fundamental and clinical research in the field of Parkinson's disease, is the real future challenge. PMID- 9363830 TI - Emerging treatments in dementia. AB - Dementia is one of the most common organic mental syndromes, usually caused by Alzheimer's disease (AD) or vascular dementia (VD) or both. Regarding AD we review the state or the art of the cholinergic approach and discuss some future options regarding preventive and nonsymptomatic strategies. Therapy for VD will consist mainly in influencing and preventing cerebrovascular pathology, because operational criteria for the diagnosis have only recently been proposed and are being discussed widely. One of the crucial problems here lies in the distinction between VD and AD and the recognition that the two disorders may be coexistent more often than assumed; the role of white matter changes seems to be particularly important. The same goes for the recognition that AD ist not a single entity. The question of heterogeneity may be solved when different therapeutic strategies are found for different subtypes. The focus of future plans should be on preventive strategies combined with an early diagnosis. PMID- 9363831 TI - Motor disorders in sleep. AB - Sleep is normally a time of motor quiescence. Motor disorders may, however, arise during the different phases of sleep. Nocturnal myoclonus or periodic leg movements in sleep usually occur during light sleep and may be considered the motor accompaniment of the cyclic fluctuations in excitability typical of such stages. Nocturnal frontal lobe epilepsy also occurs during NREM sleep and may be misdiagnosed as parasomnia. REM behavior disorders are instead dissociated episodes of REM sleep without atonia, often associated with or even heralding Parkinson's disease or multiple system atrophy. PMID- 9363832 TI - Epilepsy: advances in management. AB - Principal advances in several areas of epileptology are reviewed. Many of these currently impact upon management of patients with epilepsy. Others hold promise for future therapeutic innovations. All reflect a growing interest in this field by basic scientists and clinicians. PMID- 9363833 TI - Pain and its treatments. AB - Among many relevant topics concerning pain and its treatments, the following will be considered: (1) definition of pain; (2) physiopathology; (3) methodology for clinical trials in pain research (4) use of drugs and surgical management of pain, and (5) future directions. The definition of pain as an unpleasant subjective, sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage, does not apply to living people incapable of self-report. Thus, nonverbal behavioral information is often needed and used for pain assessment. Major landmarks concerning physiopathology were: the liberation of substance P and other neuropeptides both at the spinal and peripheral endings, the anatomical and functional analysis of the nociceptive pathways, the characterization of endomorphins ligands and receptors. The difference between 'windup' and central sensitization were emphasized. Models of neuropathic pain have advanced our understanding of its specific pathophysiology. Sensoridiscriminative aspects of pain involve lateral thalamic nuclei and corresponding somesthetic cortices, whereas medial thalamic nuclei encode nociceptive stimuli during attention-directed tasks. Their cortical connections, namely anterior cingular cortex and insular cortex, support the postulate of a role in the affective-motivational dimensions of pain. An impressive increase in the number and quality of randomised clinical trials has been observed since 1950. The use of analgesics, opioids, antidepressants and other drugs is addressed, as well as new aspects concerning surgery or new drugs. PMID- 9363834 TI - Emerging treatments in multiple sclerosis. AB - Currently used and developing therapies for multiple sclerosis (MS) are dealing with the treatment of acute exacerbations, the prevention of relapses and of the progression of neurological handicap, the treatment of symptoms, and the repair of demyelinated lesions. New insights into the treatment of acute relapses as well as recent immunomodulatory and immunosuppressive agents tested in MS are exposed in this brief review. Interferon-beta (1a and 1b), copolymer 1 and new immunosuppressive therapies are particularly discussed with emphasis on their potential to alter the course of MS. PMID- 9363836 TI - Future developments in the treatment of immune-mediated polyneuropathies. AB - The Guillain-Barre syndrome and chronic inflammatory demyelinating polyneuropathy are the most extensively studied immune-mediated neuropathies. Randomized treatment studies have been performed with corticosteroids, plasma exchange and more recently with high-dose immunoglobulins. In the future treatment may be more individualized based on specific immunological mechanisms. More immune-modulating treatments will become available also with recombinant DNA technology. This will offer new possibilities, but prior to the effective introduction of these new molecules in the clinical setting, careful consideration and clinical trials are required. PMID- 9363835 TI - Emerging treatments in myopathies. AB - Outstanding improvement has been made in the molecular understanding of several muscle diseases with the application of molecular biological techniques to the investigation of human disorders. The identification of genetic mutations has improved considerably the diagnostic approach to muscular dystrophies, mitochondrial myopathies and ion channel disorders. Important results have been achieved in the field of inflammatory myopathies. With a few exceptions, therapies available are nonspecific and rarely represent a cure for the disease. Molecular medicine offers an opportunity to design new therapeutic strategies based on the pathogenic mechanisms underlying each disease. PMID- 9363837 TI - Management of malignant brain tumors. AB - This review is made up of two parts. The first section describes techniques and methods used in the treatment of malignant brain tumors, stressing the most recent developments. The second part reviews the therapeutic modalities in malignant gliomas, where an attempt is made to consider separately glioblastomas, anaplastic astrocytomas and oligodendrogliomas, low-grade glioma, medulloblastoma, primary brain lymphoma, and brain metastases. A decision making algorithm is suggested for each tumor type. PMID- 9363839 TI - L-2-Chloropropionic acid metabolism and disposition in male rats: relevance to cerebellar injury. AB - L-2-Chloropropionic acid (L-CPA) produces selective necrosis to the granule cell layer of the rat cerebellum. As part of a study to understand the mechanism of selective toxicity we have investigated the metabolism and disposition of [2 14C]L-CPA in the rat, with particular emphasis on the brain. Following a single oral non-toxic dose of 250 mg/kg or a neurotoxic dose of 750 mg/kg or 250 mg/kg per day for 3 days, L-CPA is very rapidly absorbed from the gastrointestinal tract into the blood stream. Peak plasma concentrations of 2 mM (250 mg/kg) and 6 mM (750 mg/kg) L-CPA occurred within 1 h of dosing, and the compound was readily cleared from the plasma with a half-life of 2.6 h. The only metabolite detected in the plasma was 2-S-cysteinylpropanoic acid, presumably derived from the glutathione conjugate. About 60% of the dose is excreted in the urine in the first 24 h as unchanged L-CPA, with a smaller amount excreted as the mercapturate, 2-S-N-acetylcysteinylpropanoic acid. Little radiolabel from L-CPA is excreted in the faeces; however, approximately 18% of a 250 mg/kg dose of L CPA is eliminated as carbon dioxide. The radiolabel from [2-14C]L-CPA present in the cerebellum, forebrain and liver at all time intervals examined was L-CPA. There was some indication of retention of L-CPA in the brain relative to the plasma with a small but consistently higher concentration found in the cerebellum. Whole body autoradiography studies indicated some selective retention of radiolabel in the cerebellum after the third dose of 250 mg/kg [2-14C]L-CPA. Our findings indicate that the initial insult to the cerebellum following L-CPA administration is probably due to the parent compound however, the prolonged presence of 2-S-cysteinylpropanoic acid in the plasma and concomitant depletion of glutathione in the cerebellum may also play a role in the toxicity. The relevance of the slightly greater retention of L-CPA in the cerebellum to the selective neurotoxicity of L-CPA requires further study. PMID- 9363838 TI - UDP-GT involvement in the enhancement of cell proliferation in thyroid follicular cell proliferative lesions in rats treated with thiourea and vitamin A. AB - The mechanisms underlying enhanced cell proliferation in thyroid proliferative lesions of rats simultaneously treated with large amounts of vitamin A (VA) and thiourea (TU) were investigated. Male F344 animals were initiated with N-bis(2 hydroxypropyl)nitrosamine (2800 mg/kg body weight, single s.c. injection). Starting 1 week later, groups received water containing 0.2% TU (TU group), diet containing 0.1% VA (VA group), both 0.2% TU and 0.1% VA (TU + VA group) or tap water/basal diet without supplement (control group) for 10 weeks. The serum levels of triiodothyronine (T3) and thyroxine (T4) were decreased and the thyroid stimulating hormone (TSH) levels were elevated in the TU and TU + VA groups, with the degree of change being significantly greater in the combined treatment group. The induction of P450 isoenzymes by TU was not enhanced by VA supplementation, but uridine diphosphate glucuronosyltransferase (UDP-GT) activity in the liver was significantly increased in the TU + VA group compared to the TU group. Thyroid weights were increased in both the TU and TU + VA groups, this being more pronounced with VA supplementation. Thyroid follicular cell hyperplasias and neoplasias were induced to similar extents in both TU treated groups, but their cell proliferation appeared to be increased by the VA supplementation. The results of the present study suggest that enhanced cell proliferation is due to increased TSH stimulation, resulting from the decrease in serum T3/T4 levels brought about by induction of liver UDP-GT activity with the combined action of TU + VA as well as inhibition by TU of thyroid hormone synthesis in the thyroid. PMID- 9363840 TI - Protective effects of vitamin E and C on cisplatin nephrotoxicity in developing rats. AB - The kinetics of vitamin E was followed in serum, liver and kidney of 10- and 55 day-old rats after the administration of a single i.m. dose of 100 mg alpha tocopherol acetate/100 g body wt. The basal levels without vitamin E administration were significantly higher in serum and liver of 10- than 55-day old rats. The effect of vitamin E on cisplatin (CP; 0.6 mg/100 g body wt., i.p.) nephrotoxicity was investigated by determining urinary volume and protein excretion, as well as the concentration of blood urea nitrogen (BUN) and lipid peroxides in renal tissue (LPO). Previously described age differences in CP nephrotoxicity were confirmed. The administration of vitamin E, 12 h prior to CP, diminished the toxic effect of CP in young and adult rats. This effect could not be enhanced by a second administration of vitamin E. The simultaneous administration of vitamin E and C 12 h prior to CP intensified the protective effect of a single administration of vitamin E in 10- and 55-day-old rats without influencing the concentration of platinum in renal tissue. PMID- 9363842 TI - Absence of a differential induction of cytochrome P450 2E1 by different alcoholic beverages in rats: implications for the aetiology of human oesophageal cancer. AB - Alcohol is an important risk factor for human oesophageal cancer. There is evidence from epidemiological studies that some specific alcoholic drinks, e.g. Calvados apple brandy, are associated with a greater risk than others. Alcohol induces cytochrome P450 2E1 (CYP2E1) and the hypothesis was tested that different alcoholic beverages, containing a variety of alcoholic compounds, could differentially induce expression of cytochrome P450 enzymes. Twelve groups of five rats each were treated for 3 days with different alcoholic beverages (ethanol alone, whisky, farm-produced or commercial Calvados brandy, beer, cider, wine) adjusted to 4, 10 or 20% of ethanol in drinking water. Immunoblotting using a monoclonal antibody specific for rat CYP2E1 revealed a single protein band in liver microsomes. Densitometric quantitation of microsomal proteins demonstrated a significant two-, three- and sixfold increase in band intensity after treatment with ethanol concentrations of 4, 10 and 20% respectively, compared to control rats drinking water alone. There was a dose-dependent increase in liver microsomal metabolism of CYP2E1 substrates (para-nitrophenol and dimethyl nitrosamine) in ethanol-treated rats. However, there were no significant differences in the level of CYP2E1 protein or enzymatic activity between the different alcoholic beverages at the same ethanol concentration. There was a slight increase in hepatic CYP1A-related enzymatic activities in the alcohol treated rats compared to the controls, but no difference between the treated groups either with dose of ethanol or type of beverage. These data show that induction of CYP2E1 with acute alcohol treatment is predominantly determined by the ethanol content of the beverage. PMID- 9363841 TI - Undernutrition during hyperoxic exposure induces CYP2E1 in rat liver. AB - Induction of cytochrome P450 2E1 (CYP2E1) has been shown to occur through two distinct mechanisms. The first is seen by treatment of rats with acetone, pyrazole, and 4-methyl-pyrazole, which induces CYP2E1 protein without affecting the mRNA level. The second is observed in starvation, diabetes, and obesity, in which an increase of CYP2E1 protein is associated with an increase of the CYP2E1 mRNA. It has been reported by (Tindberg and Ingelman-Sundberg 1989) that hyperoxic exposure (95% O2) induced a several-fold increase of CYP2E1 protein in both the liver and lung of exposed rats without affecting the level of CYP2E1 mRNA. During the course of our previous study which demonstrated hyperoxia induced specific pretranslational induction of CYP1A1/2 in the liver and CYP1A1 in the lung, we observed a progressive increase of hepatic CYP2E1 mRNA in animals of the hyperoxia group. Hyperoxia is accompanied by some degree of starvation and our earlier experiments were conducted with rats of significantly greater body weight than those used by Tindberg and Ingelman-Sundberg (260 vs 150 g). Thus we reevaluated the changes of CYP2E1 in the current study with the use of food restricted control, and by utilizing rats of comparable weight (approximately 150 g) to that utilized by Tindberg and Ingelman-Sundberg. The results obtained in the present study showed that there was a significant increase in the levels of hepatic CYP2E1 mRNA, protein, and p-nitrophenol hydroxylase activity in the food restricted control group compared to the untreated controls. Rats from the hyperoxia group also demonstrated a similar increase of these three parameters in their livers but showed no significant difference compared with the results of the food-restricted control group. Rats weighing approximately 260 g were also examined with similar food restriction and hyperoxia, and the results were essentially similar to those obtained with the younger rats. The lungs of rats from food-restricted control and hyperoxia groups showed no increase of any of the CYP2E1 parameters. The results obtained in the current study, therefore, indicate that hyperoxia has no effect on CYP2E1 expression in both the liver and lung. Increased CYP2E1 mRNA, protein, and p-nitrophenol hydroxylase activity seen in the liver of rats, but not in the lungs, are consistent with the notion that undernutrition during hyperoxia is the underlying mechanism for this induction. PMID- 9363843 TI - Age dependent differential effects of cigarette smoke on hepatic and pulmonary xenobiotic metabolizing enzymes in rats. AB - The effects of cigarette smoke (CS) on hepatic and pulmonary monooxygenase (MO) activities (aniline 4-hydroxylase, AH; aminopyrine N-demethylase, AMND; 7 ethoxyresorufin O-deethylase, EROD; p-nitroanisole O-demethylase, p-NAOD), lipid peroxidation (LP), and reduced glutathione (GSH) levels and glutathione S transferase (GST) activities toward several substrates (1-chloro-2,4 dinitrobenzene, CDNB; 1,2-dichloro-4-nitrobenzene, DCNB; ethacrynic acid, EAA; 1,2-epoxy-3-(p-nitrophenoxy)-propane, ENPP) were determined in 20-, 90- and 360 day-old male rats. The animals were exposed to CS five times a day, with 1 h intervals, for 3 days in a chamber supplied alternatively with smoke and fresh air, and were killed 16 h after the last treatments. The hepatic AH activity increased significantly in 20-day-old rats and remained unaltered in older age groups. The hepatic AMND activity unaltered, significantly increased and decreased in 20-, 90- and 360-day-old rats, respectively. The pulmonary AH activity increased significantly in 20- and 90-day-old rats whereas no alteration was noted in 360-day-old rats. CS was ineffective on pulmonary AMND activity at all ages. CS increased hepatic and pulmonary EROD and p-NAOD activities significantly in all age groups compared to controls. In liver, LP level was significantly increased, decreased, and unaltered in 20-, 90- and 360-day-old rats, respectively. CS increased hepatic GSH level significantly in 90-day-old rats but was not effective in the other age groups. In lung, LP level was increased in 90- and 360-day-old rats and unaltered in 20-day-old rats. CS increased pulmonary GSH level significantly in 90-day-old rats and did not have any effect in the other age groups. The hepatic GST activities toward CDNB and DCNB decreased significantly in 360-day-old rats and were unaltered in the younger age groups. The hepatic GST activity toward EAA was unaltered, significantly increased and decreased in 20-, 90- and 360-day-old rats, respectively. The hepatic GST activity toward ENPP decreased significantly in 20- and 90-day-old rats but was unaltered in the oldest group of rats. In 20-day-old rats, the pulmonary GST activity toward ENPP increased significantly whereas the other GST activities did not alter. In 90-day-old rats, however, CS significantly decreased all the pulmonary GST activities studied. Unaltered DCNB GST, significant increase in EAA GST and decrease in CDNB and ENPP GST activities of lung were noted in 360-day-old rats. These results reveal that the regulation in rats of hepatic and pulmonary MO and GST activities are differentially influenced by CS as a function of age. PMID- 9363844 TI - Distribution studies in CD-1 mice administered [14C]muconaldehyde. AB - Trans,trans-muconaldehyde (muconaldehyde, MUC), a microsomal hematotoxic ring opened metabolite of benzene, has been proposed to play a role in benzene hematotoxicity. In the present study, [14C]muconaldehyde was administered to CD-1 mice and the distribution of [14C]muconaldehyde equivalents was investigated. The study was carried out to evaluate whether [14C]muconaldehyde equivalents could reach the bone marrow. [14C]Muconaldehyde at a dose of 2 mg/kg was administered intraperitoneally (3.4 microCi/mouse) and by intravenous injection (2.7 microCi/mouse). The amount of [14C]muconaldehyde equivalents was measured in the bone marrow, blood, liver, lung, kidney and spleen at 0.25, 0.5, 1, 2, 4, and 24 h after [14C]MUC administration. The results indicate that 0.044% or 0.018% of the total dose administered when given i.v. or i.p., respectively, reached the bone marrow. The elimination of the radioactivity in all organs had at least two phases. The bone marrow, kidney, and lung had a rapid first phase (t1/2 0.5-1.2 h) and a slower second phase (t1/2 2.8-15.7 h). In the liver, a slow first phase (t1/2 3.7 h) was followed by a more rapid second phase (t1/2 1.5 h). The level of radioactivity in blood and bone marrow was significantly higher when [14C]muconaldehyde was administered intravenously compared with intraperitoneally, demonstrating that the route of administration affects the distribution of [14C]muconaldehyde equivalents. PMID- 9363846 TI - Direct reaction of oximes with sarin, soman, or tabun in vitro. AB - The direct reaction of seven pyridinium oximes with the nerve agents sarin, soman, and tabun was followed by a spectrophotometric method. The half-lives (t1/2) of the oximes, the first- and second-order rate constants (k1, k2), and the maximal reaction velocity (vmax) were calculated according to changes in the absorbance of the zwitterion (betaine) peak. In all cases the reaction velocity of the nerve agents with any of the oximes was highest with tabun, followed by sarin and then soman. Comparing the reaction rates of three therapeutically used oximes with the same nerve agent, the highest rate was obtained for soman with obidoxime, for sarin with 2-PAM, and for tabun with HI 6. The maximal reaction velocities reveal that the detoxification of the nerve agents by direct reaction with oximes and the subsequent decomposition of the phosphonyl oxime in vivo do not substantially contribute to the therapeutic effect of these antidotes. PMID- 9363845 TI - Effects of ochratoxin A on DNA repair in cultures of rat hepatocytes and porcine urinary bladder epithelial cells. AB - In cultured rat hepatocytes the mycotoxin ochratoxin A (OTA) induced unscheduled DNA synthesis (UDS) only in a narrow concentration range. Using a culture medium supplemented with 1% fetal calf serum, at 750 nM OTA a weak induction and at 1 microM OTA a marked induction of DNA repair was observed (15 +/- 11 and 38 +/- 24% cells in repair, respectively). Concentrations > 1 microM OTA were cytotoxic, and <750 nM no induction occurred. In cultures of cells from the urinary bladder (porcine urinary bladder epithelial cells; PUBEC), a target organ of the mycotoxin, OTA induced UDS in a concentration-dependent manner. To inhibit the proliferation of the cultured epithelial cells, which would counteract the detection of DNA repair, epidermal growth factor was omitted and an arginine deficient medium (ADM) was used. Under these serum-free culture conditions the amount of cells undergoing DNA repair in PUBEC control cultures was approximately 7 +/- 4%, a value also comparable to those of control cultures of rat hepatocytes. At concentrations between 250 nM and 1 microM OTA a concentration dependent increase of cells in repair was observed. Above 1 microM OTA was cytotoxic. At this concentration a maximum of approximately 61 +/- 9% of the cells undergo DNA repair. This amount is comparable to control cultures incubated with 5 or 10 mM ethylmethane-sulphonate (EMS) (49 +/- 9 and 69 +/- 10% cells in repair, respectively), used as a positive control. These results show that in cultured rat hepatocytes induction of UDS is relatively weak whereas in urothelial cells this effect was significant. Whether this effect is due to OTA metabolites formed locally in the urothelium cannot be excluded since PUBEC have been shown to be able to metabolize xenobiotics independently from the liver. PMID- 9363847 TI - A note on the physiological background of the ethylene oxide adduct 7-(2 hydroxyethyl)guanine in DNA from human blood. AB - A newly developed high-performance liquid chromatography (HPLC) method involves derivatization with phenylglyoxal and fluorescence detection, using 7 methylguanine as internal standard. The physiological background of the adduct 7 (2-hydroxyethyl)guanine in DNA isolated from human blood was determined by this method. In five persons the range of the adduct was between 2.1 and 5.8 pmol/mg DNA (mean 3.2). This finding is consistent with previous data obtained by others, using different analytical methods, and points to an intrinsic carcinogenic risk due to endogenous ethylene oxide. PMID- 9363848 TI - Effects of single exposure to toluene vapor on the expression of immediate early genes and GFAP gene in the mouse brain. PMID- 9363849 TI - VIP -- a 'very important peptide' in the sympathetic nervous system? AB - Vasoactive intestinal peptide (VIP) is involved in the control of smooth muscle activity, blood flow and exo- as well as endocrine secretion. More recent work has elucidated the effects of this peptide on central and peripheral neurons. These studies suggest that VIP is an important modulator of cell growth, differentiation and neuronal survival during development of the sympathetic nervous system. VIP is also expressed in a subset of adult postganglionic sympathetic neurons. Furthermore, VIP is induced in an additional neuronal subpopulation of the rat superior cervical ganglion after axotomy. The mechanisms leading to increased VIP expression and its possible role during sympathetic nerve regeneration are currently being elucidated. This review summarizes the distribution, regulation and functions of VIP in cervical sympathetic ganglia of higher vertebrates. PMID- 9363850 TI - Loss of primary afferent nerve terminals in the brainstem after peripheral nerve transection: an anatomical study in monkeys. AB - In order to investigate the changes in the somatosensory organization that occur after a peripheral nerve injury, a purely sensory nerve (radial nerve - superficial branch) was divided in adult monkeys (Macaca fascicularis). The nerve ends were immediately rejoined by an epineural suturing technique. After 6-21 months the nerve investigated was exposed to an intra-axonal nerve tracer (horseradish peroxidase conjugate) in order to label the primary afferent terminals within the cuneate nucleus of the brainstem. The non-transected nerve on the contralateral side was similarly exposed and served as a control. Terminal labelling was seen throughout the cuneate nucleus, mainly in the middle of its rostro-caudal extension, and in this part it showed a patchy appearance superimposed on cell clusters within the pars rotunda. This pattern of distribution was seen both on the experimental and control sides. On the experimental side there was an obvious loss of terminal labelling within the terminal field as estimated using an image-analysing system: Compared with the contralateral side the median loss (peroxidase activity) was 83% and between 6 and 21 months only minor restoration of the terminal intensity was observed. These results in the primate confirm earlier results in the cat that transection and microsurgical repair of a sensory nerve causes a considerable loss of neurons capable of intraaxonal transport. PMID- 9363851 TI - Localization of types I, II and X collagen and osteocalcin in intramembranous, endochondral and chondroid bone of rats. AB - Chondroid bone is a unique calcified tissue intermediate between bone and cartilage. To clarify its characteristics, we examined the distributions of the ECMs associated with chondrogenic differentiation and matrix calcification in the chondroid bone of the rat glenoid fossa, and compared them to those in two typical bone tissues, alveolar bone of the maxilla (intramembranous bone) and the growth plate of long bone (endochrondral bone), using immunofluorescence techniques. Morphologically, the glenoid fossa consisted of the fibrous, progenitor and cartilaginous cell layers and the cartilaginous cell layer was further divided into the superficial non-hypertrophic layers (secondary cartilage) and the deep hypertrophic cell layers (chondroid bone). The co distribution of type I and type II collagens was observed in secondary cartilage and chondroid bone, whereas type X collagen was restricted to the pericellular matrix of hypertrophied cells (chondroid bone). Osteocalcin, which was absent from the calcified cartilage of endochondral bone formation, was also present in the ECM of the chondroid bone, but not in cells. These results demonstrate that chondroid bone of rats, which is adjacent to secondary-type cartilage in the glenoid fossa, has phenotypic expressions associated with both hypertrophied chondrocytes and osteocytes. PMID- 9363853 TI - Genetic background effects on dental and other craniofacial abnormalities in homozygous small eye (Pax6Sey/Pax6Sey) mice. AB - Small eye (Pax6Sey) is a semi-dominant mutation affecting development of the eyes, brain and nasal structures. The mutant phenotype arises from defects within the Pax6 gene and several mutant alleles have been identified. A previous study reported that Pax6Sey/Pax6Sey homozygotes, in a random-bred stock, had a median cartilaginous rod-like structure in the nasal region and 80% had supernumerary upper incisor teeth. In this study we show that supernumerary upper incisor teeth and a previously unreported nasal capsule-derived cartilaginous 'spur' occur in compound heterozygous Pax6Sey-Neu/Pax6Sey and homozygous Pax6Sey/Pax6Sey fetuses from several strains of mice. The frequencies of the abnormal phenotypes were not related to allele type but showed variable penetrance, which was dependent on genetic background. The median nasal cartilaginous rod-like structure was present in all homozygous small eye fetuses. The Pax6Sey/Pax6Sey homozygote may provide insight into the complex gene interactions involved in eye, nasal and craniofacial morphogenesis. PMID- 9363852 TI - Sphincters of canine hepatic sublobular veins respond to endothelin-1 and 3. AB - The dog has been used repeatedly as a model in liver transplantation research. The microcirculation and its regulatory mechanisms play a crucial role during ischemia and reperfusion. Little is known about the role of venous sphincters in regulating blood flow in the dog liver. Hence, we performed this study to elucidate their potential role in regulating local blood flow. In 14 dogs mean systemic (MSP) and mean portal venous pressure (MPP) were measured. Light and electron microscopy (scanning and transmission) of tissue sections and vascular corrosion casts were used to elucidate the microvascular morphology. Immunocytochemistry was applied to identify smooth muscle cells and the innervation of venous sphincters. Endothelins 1 and 3 were injected to find whether the hepatic venous sphincters are sensitive to these vasoactive agents. Tufts of smooth muscle cells were found in the sublobular veins (SLV; 100 to 250 microm in diameter), that reduced the luminal diameters of veins by 34%. Nerve endings were not observed close to these venous sphincters. The MSP and MPP were 75.3+/-2.4 mmHg and 8.9+/-0.95 mmHg, respectively. Treatment with 1.0 microg/kg of endothelin-1 (ET-1) significantly increased the MSP, the MPP and the percentage of focal venous sphincter contraction by 39% (105+/-4.7 mmHg), 43% (12.8+/-1.7 mmHg) and 57% (53.5+/-4.7), respectively (P <0.01). Treatment with ET 3 caused a significant (P <0.01) decrease in the MSP, the MPP and the percentage of sphincter contraction by 19% (61.0+/-2.2 mmHg), 39% (5.8+/-2.9 mmHg) and 38% (20.9%+/-3.15). Sinusoids did not contain sphincters. Hepatic arterioles and central veins were not affected by ET-treatment. The contraction of SLV sphincters correlated with increases in MPP (r=0.81, P <0.01) and was related to the MSP (r=0.67, P <0.01). These data show that the smooth muscle sphincters in SLV of the dog liver are involved in the local regulation of blood flow and that these sphincters are stimulated by non-neurogenic mechanisms. These sphincters contract in response to ET-1 and relax in response to ET-3. Since ET-1 is released during and/or causes inflammation, e.g., during ischemia and reperfusion, its antagonists might be of benefit during transplantation reperfusion of liver. PMID- 9363854 TI - Crural Herbst corpuscles in chicken and quail: numbers and structure. AB - Herbst corpuscles were studied in the crural region of perinatal and adult chicken and quail in order to find out their number and dimensions and to learn more about their structure, especially in relation to size. Crural corpuscles are arrayed in an encapsulated string between tibia and fibula. They are closely packed together; a small number of corpuscles is found apart from the string, often attached to the periost. The strings of corpuscles are approximately 40 mm long in adult chicken and 20 mm long in the quail. The crural region of the chicken contains 382.8 +/- 90.9 (mean +/- SD) corpuscles, the numbers ranging from 301 to 582; in the quail, the mean number is 119.2 +/- 27.9, with a range from 83 to 167 corpuscles. In the chicken, one axon supplies an average of 1.60 corpuscles; in the quail, the relation of axons to corpuscles is approximately 0.92. In both species, final numbers of crural corpuscles are already attained before hatching and no difference is found in the mean number and range of corpuscles between perinatal and adult birds. In both chicken and quail, individual strings contain corpuscles of various sizes, from large to very small. The chicken corpuscles are generally twice as large in diameter and often longer than those of the quail. The corpuscles are composed of an axon terminal that projects two rows of axonal spines into the clefts of the inner core and ends with an ultraterminal bulb; the terminal is surrounded with a bilaterally symmetrical inner core, amorphous inner space containing collagen fibrils of various thickness, and a capsule. Large chicken corpuscles contain inner cores composed of up to 100 lamellae, while quail inner cores have half that number at the most. The capsules are usually composed of 8 to 10 lamellar layers in both species, but they are thicker in the chicken than in the quail. The possible functional significance of individual structural components of Herbst corpuscles is discussed. PMID- 9363855 TI - Immunolocalization and heart levels of GRP94 in the mouse during post implantation development. AB - Glucose-regulated proteins (GRPs), which belong to the highly conserved family of stress proteins, are resident to the endoplasmic reticulum and function as molecular chaperones. Heat shock proteins have been shown to be developmentally regulated, but little work has been done to investigate the expression of GRPs during embryogenesis. Therefore, this study examined the distribution of GRP94 within mouse embryos during the period of organogenesis and characterized levels of GRP94 within the developing heart during organogenesis and late fetal stages. Our results demonstrate that the GRP94 protein is constitutively expressed within mouse embryos during early stages of organogenesis and is localized particularly within the developing heart, neuroepithelium, and surface ectoderm tissues. Positive staining for GRP94 remains within developing heart tissues throughout organogenesis and is found primarily within the atrial and ventricular myocardial cells. Western blot analysis of GRP94 expression demonstrates a significantly higher level of GRP94 in embryonic hearts during early stages of organogenesis than in later stages of organogenesis or the fetal period. These results demonstrate that the stress protein GRP94 is constitutively expressed within specific tissues during post-implantation mouse development and suggest that GRPs may play an important role in the process of myocardial cell differentiation and heart development. PMID- 9363856 TI - Three-dimensional structure of the human cerebellar dentate nucleus: a computerized reconstruction study. AB - To explore the regional differences in neuronal cytoarchitecture of human dentate nucleus, we examined first the three-dimensional structure of this nucleus with a computerized reconstruction technique, after making serial sections of the brain in seven fetuses aged from 20 to 39 weeks of gestation (WG), an infant (1-month old) and two adults (22- and 85-year-old). The surface was broadly smooth at 20 22 weeks, but primary gyri or fissures were noticed in the rostral half of the lateral surface, earliest in its dorsal region. A small cavity (the hilus nuclei dentati) was situated in the middle of the medial surface, with four distinct margins. A great progress in gyration was noted after 22 weeks: gyri were observed over the entire surface by 28-29 weeks. Gyri were thicker in the caudal half than the rostral half both in the lateral and the medial surfaces. At this stage, the rostral margin of the hilus was partially cut off and the hilus was elongated toward the rostral tip, but its relative size appeared to be grossly equal to that at 22 weeks. The hilus began to open wider and wider after 30 weeks. Subdivision of the human dentate nucleus into two different parts (the smaller microgyric rostral part and the larger macrogyric caudal part) was accomplished by 35 weeks. We have previously, using morphometric approaches, reported that a vulnerable (or critical) period may exist during 20-30 weeks in the fetal development of the dentate nucleus. It is possible that this special ten weeks of mid-gestation may be coincident with the time of extensive growth in gyration for this nucleus. It will be necessary to sample the neurons independently from at least two different parts, as described above, to design further microscopic studies on the regional differences or on other cytological investigations. PMID- 9363857 TI - "Cancer defeated": not if, but when--introducing the Biology of Neoplasia series. PMID- 9363858 TI - Chemotherapy for advanced gastric cancer: where do we stand? PMID- 9363859 TI - Role of the retinoblastoma protein in the pathogenesis of human cancer. AB - The retinoblastoma gene (RB-1) was originally identified as the gene involved in hereditary retinoblastoma. However, RB-1 mutations are found in a number of common mesenchymal and epithelial malignancies. The retinoblastoma protein (pRB) acts as a transcriptional regulator of genes involved in DNA synthesis and cell cycle control. In this regard, the functional interaction between pRB and the E2F transcription factor family appears to be critical. The pRB-E2F interaction is, in turn, regulated by a pathway that includes cyclin D1, cdk4, and p16. Mutations that affect this pathway have been documented in nearly every type of adult cancer. Thus, perturbation of pRB function may be required for the development of cancer. Insights into the biochemical functions of pRB, and its upstream regulators, may form the basis for the development of novel antineoplastic agents. PMID- 9363860 TI - Intensive weekly chemotherapy for advanced gastric cancer using fluorouracil, cisplatin, epi-doxorubicin, 6S-leucovorin, glutathione, and filgrastim: a report from the Italian Group for the Study of Digestive Tract Cancer. AB - PURPOSE: A multiinstitutional trial was performed to confirm the clinical activity, in terms of response rate and toxicity (primary objectives) and duration of responses and survival (secondary objectives), of an intensive weekly regimen in advanced gastric cancer. PATIENTS AND METHODS: Patients with measurable unresectable and/or metastatic gastric carcinoma received 1-day per week administration of cisplatin (CDDP) 40 mg/m2, fluorouracil (5FU) 500 mg/m2, epi-doxorubicin (epi-ADR) 35 mg/m2, 6S-stereoisomer of leucovorin 250 mg/m2, and glutathione 1.5 g/m2. On the other days, filgrastim was administered by subcutaneous injection at a dose of 5 mg/kg. One cycle of therapy consisted of eight 1-week treatments. Patients who showed a response or stable disease received a further 6 weeks of therapy. RESULTS: Of 105 enrolled patients, 11 had locally advanced unresectable disease only; 33 had primary nonresected and metastatic disease; 48 had metastatic disease and primary tumor resected; 10 had locoregional recurrence and metastatic disease; and three had locoregional recurrence only. After one cycle, 18 complete responses (CRs) and 47 partial responses (PRs) were achieved, for an overall response rate of 62% (95% confidence interval [CI], 53% to 71%). Twenty patients had stable disease and 20 progressed on therapy. The median survival duration of all 105 patients was 11 months, with 1- and 2-year survival rates of 42% and 5%, respectively. World Health Organization (WHO) grade III to IV toxicity, in terms of anemia, neutropenia, thrombocytopenia, and mucositis, was experienced by 40 patients (38%). There were no treatment-related deaths. CONCLUSION: These data support the results of the pilot study and confirmed the high activity of the regimen, with acceptable toxicity. This schedule deserves evaluation in the adjuvant setting. PMID- 9363861 TI - Prospectively randomized North Central Cancer Treatment Group trial of intensive course fluorouracil combined with the l-isomer of intravenous leucovorin, oral leucovorin, or intravenous leucovorin for the treatment of advanced colorectal cancer. AB - PURPOSE: A three-arm randomized phase III trial in advanced colorectal cancer patients was designed to test whether substitution of an equivalent dose of (1) l leucovorin or (2) oral leucovorin would more effectively potentiate fluorouracil (5-FU) than standard intravenous (I.V.) (d,l)-leucovorin. PATIENTS AND METHODS: A total of 926 chemotherapy-naive patients participated. Patients received one of three treatments: (A) intensive-course 5-FU plus l-leucovorin with I.V. leucovorin (Immunex Corp, Seattle, WA) at 100 mg/m2 and I.V. 5-FU at 370 mg/m2; (B) intensive-course 5-FU plus oral (d,l)-leucovorin with oral leucovarin at 125 mg/m2 on hours 0, 1, 2, and 3 (total dose, 500 mg/m2) followed by 5-FU 370 mg/m2 on hour 4; or (C) intensive-course 5-FU plus I.V. (d,l)-leucovorin with I.V. leucovorin 200 mg/m2 and 5-FU 370 mg/m2. Drugs were administered daily for 5 consecutive days. Courses were repeated at 4 and 8 weeks, and every 5 weeks thereafter. Dosage was reduced for neutropenia, thrombocytopenia, diarrhea, stomatitis, and dermatitis. RESULTS: Of 926 eligible patients, 756 have died. The overall response rate for patients with measurable disease was 32% (165 of 514). There were no differences between regimens in response rates (arm A, 28% [47 of 140]; arm B, 34% [60 of 174]; and arm C, 34% [58 of 170]) or in survival. There have been nine possible chemotherapy-related fatalities. Grade III to IV toxic effects did not differ appreciably by arm and included stomatitis (12% to 14%), diarrhea (15% to 19%), nausea (7% to 9%), and vomiting (6% to 8%). CONCLUSION: There was no difference in response, survival, or toxicity between these three different leucovorin formulations combined with 5-FU. PMID- 9363862 TI - Phase I trial and pharmacokinetic study of all-trans-retinoic acid administered on an intermittent schedule in combination with interferon-alpha2a in pediatric patients with refractory cancer. AB - PURPOSE: To determine the maximum-tolerated dose (MTD) of all-trans-retinoic acid (ATRA) administered on an intermittent oral schedule with interferon-alpha2a (IFN alpha2a) in children with refractory cancer, and whether the marked reduction in plasma ATRA concentrations observed with chronic daily oral dosing could be circumvented with an intermittent dosing schedule. PATIENTS AND METHODS: Thirty three children with refractory cancer (stratified by age, < or = 12 and > 12 years) were treated with ATRA 3 consecutive days per week and IFN-alpha2a 3 x 10(6) U/m2 5 consecutive days per week, both repeated weekly. The starting dose of ATRA was 60 mg/m2/d divided into three doses, with planned escalations to 90 and 120 mg/m2/d. Because severe headaches have been noted to occur on the initial day of ATRA administration, only two of three doses of ATRA were administered on day 1 of each week. RESULTS: Pseudotumor cerebri or dose-limiting headache was observed in two of five patients older than 12 years treated at the 120-mg/m2/d dose level and in one of six < or = 12 years at the 90-mg/m2/d level. Other non dose-limiting toxicities of ATRA included reversible elevations in hepatic transaminases and triglycerides, dry skin, cheilitis, and nausea/vomiting. One child with recurrent neuroblastoma had an objective response of 6 months' duration, and one with recurrent Wilms' tumor had histologic maturation of multiple tumors. This intermittent schedule allowed for exposure to relatively high plasma concentrations of ATRA on a repetitive basis. Following 30-mg/m2 doses, the ATRA area under the concentration-time curve (AUC) decreased from 96 +/- 14 micromol/L/min on day 1 to 26 +/- 24 micromol/L/min by day 3 of drug administration, but on day 1 of the fourth consecutive week of therapy, the AUC averaged 110 +/- 16 micromol/L/min. The recommended pediatric phase II dose of ATRA administered on this schedule is 90 mg/m2/d. CONCLUSION: An intermittent schedule of ATRA administration appears to circumvent the low plasma drug exposure that is a result of the sustained upregulation of metabolism when this drug is administered on a chronic daily schedule. Based on the results of this trial, a phase II trial of ATRA/IFN-alpha2a in neuroblastoma and Wilms' tumor using this schedule is in progress. PMID- 9363863 TI - Alternating MOPP and ABVD chemotherapy plus mantle-field radiation therapy in patients with massive mediastinal Hodgkin's disease. AB - PURPOSE: To evaluate the efficacy and toxicity of mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy plus mantle-field radiation therapy in the treatment of patients with massive mediastinal Hodgkin's disease of any stage. PATIENTS AND METHODS: Eighty patients presented with Hodgkin's disease and a mediastinal mass greater than one third the greatest chest diameter on chest radiograph. Patients were staged and treated with MOPP alternated with ABVD chemotherapy for a total of six cycles. Patients then received 10 Gy mantle-field radiation therapy delivered to the original extent of disease followed by 25 to 35 Gy to the residual abnormalities. RESULTS: The complete response (CR) rate was 89%. With a median follow-up duration of 10 years, disease-free survival of the complete responders is 78% at 15 years and overall survival is 75% at 15 years. For patients with stage I or II disease, disease-free survival was 76% at 15 years and overall survival was 79%; for those with stage III or IV disease, disease-free survival was 82% at 15 years and overall survival was 64%. Age, stage, sex, B symptoms, number of extranodal sites, lactate dehydrogenase (LDH) levels, erythrocyte sedimentation rate, and platelet count did not influence treatment outcome. Treatment-related pneumonitis was noted in 16% of patients (fatal in one), mainly in those older than age 35 years who received total doses of radiation therapy greater than 42 Gy. Fertility is more often preserved with MOPP/ABVD therapy than with MOPP chemotherapy and there appears to be less pulmonary and cardiac disease than with ABVD chemotherapy. Two patients have developed second solid tumors within radiation ports and one relapsed patient developed acute leukemia after MOPP salvage therapy. CONCLUSION: MOPP/ABVD followed by mantle-field radiation therapy is an effective treatment for all stages of Hodgkin's disease that present with a large mediastinal mass. Our data suggest that the large mediastinal mass is a more dominant determinant of prognosis than Ann Arbor stage or other clinical prognostic factors. PMID- 9363864 TI - Successful pregnancy after allogeneic bone marrow transplant with embryos isolated before transplant. AB - METHODS AND RESULTS: Autologous embryos from in vitro-fertilized ova were successfully implanted in a 29-year-old woman, 2 years after successful allogeneic bone marrow transplant (BMT) for chronic myeloid leukemia (CML). A second pregnancy, similarly initiated, is in progress at 4 years posttransplant. CONCLUSION: Our experience offers a fertility-salvaging technique to some women after cytotoxic therapy, where time permits ovarian hyperstimulation before the need for definitive myeloblative therapy of their malignancy, and where the risk of subsequent infertility is high. PMID- 9363865 TI - Use of octreotide in the symptomatic management of diarrhea induced by graft versus-host disease in patients with hematologic malignancies. AB - PURPOSE: Diarrhea associated with acute gastrointestinal (GI) graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT) can result in severe morbidity and mortality. A pilot study was conducted to evaluate the efficacy and toxicity of octreotide in the management of diarrhea in patients with GVHD after allogeneic BMT. PATIENTS AND METHODS: Twenty-one patients entered the study. Patients received either peripheral-blood stem cells (n = 13) or bone marrow (n = 8). Seven patients had grade 4, 13 grade 3, and one grade 2 GVHD. Intravenous (I.V.) octreotide 500 microg every 8 hours for 7 days was administered. Octreotide treatment was discontinued if no response was observed after 7 days or for grade 4 toxicity. RESULTS: Fifteen (71%) of 21 treated patients had a complete response within 7 days of the initiation of octreotide; three (14%) had a partial response and three (14%) failed to respond to treatment. Toxicities were minimal; hyperglycemia was seen in four patients and one patient developed a partial ileus. Octreotide was discontinued and the ileus resolved within 48 hours. CONCLUSION: If initiated early in the course of GI GVHD, octreotide appears to be an effective, well-tolerated agent in reducing severe voluminous diarrhea. Octreotide should be discontinued within 24 hours after the resolution of diarrhea to avoid the development of ileus. Because no additional reduction in the volume of diarrhea occurred after 7 days of therapy, continuation of the drug beyond this time is not cost effective. PMID- 9363866 TI - CD30 ligand in lymphoma patients with CD30+ tumors. AB - PURPOSE: CD30 ligand (CD30L), which is expressed on resting B and activated T lymphocytes, can induce cell death in several CD30+ cell lines. Patients with CD30+ tumors (Hodgkin's disease and Ki-1+ non-Hodgkin's lymphoma) frequently have elevated soluble CD30 (sCD30) levels in their serum, which correlates with a poor prognosis. The role of sCD30 in protecting tumor cells from CD30L-mediated cell death and the pattern of CD30L expression on human peripheral-blood lymphocytes (PBLs) of normal donors and patients with CD30+ tumors are investigated. MATERIALS AND METHODS: CD30L surface protein expression was determined by two color flow cytometry on PBLs of patients with CD30+ tumors and normal individuals. CD30L levels were determined on subsets of PBLs before and after stimulation with phytohemagglutinin (PHA), anti-CD3 antibody, or CD40L. sCD30 was measured by enzyme-linked immunosorbent assay (ELISA). The apoptotic activity of membrane-bound CD30L was tested in a CD30+ cell line by the annexin V-binding method. RESULTS: Unstimulated T lymphocytes of normal donors and patients with lymphoma rarely expressed CD30L surface protein, but were able to express it after stimulation with PHA or anti-CD3 antibody. Resting B cells of patients with CD30+ tumors had lower levels of detectable surface CD30L compared with normal donors (mean, 55% and 80.6%, respectively; P = .0008). Patients with high levels of serum sCD30 had lower detectable levels of CD30L on their PBLs (R2 = .72, P = .0008) and exogenous sCD30 blocked membrane-bound CD30L-mediated apoptosis in a CD30+ cell line. CONCLUSION: In patients with CD30+ tumors, sCD30 can decrease the availability of CD30L on PBLs. Blocking the apoptosis-inducing activity of CD30L by its soluble receptor may explain how CD30+ tumors escape immunosurveillance and may be related to the reported poor prognosis of patients who have elevated sCD30 levels. PMID- 9363868 TI - Randomized placebo-controlled study of recombinant human interleukin-11 to prevent chemotherapy-induced thrombocytopenia in patients with breast cancer receiving dose-intensive cyclophosphamide and doxorubicin. AB - PURPOSE: Thrombocytopenia may compromise cancer treatment, causing chemotherapy dose reductions, schedule alterations, or the need for platelet transfusions. We evaluated the efficacy and safety of recombinant human interleukin-11 (rhIL-11; Neumega, Genetics Institute, Inc, Cambridge, MA), a novel thrombopoietic growth factor, in reducing the need for platelet transfusions in patients who undergo dose-intensive chemotherapy. PATIENTS AND METHODS: Women with advanced breast cancer received cyclophosphamide (3,200 mg/m2) and doxorubicin (75 mg/m2) plus granulocyte colony-stimulating factor (G-CSF; 5 microg/kg/d). Patients were randomized to blinded treatment with placebo or 50 microg/kg/d rhIL-11 subcutaneously for 10 or 17 days after the first two chemotherapy cycles. RESULTS: Seventy-seven patients were randomized and constitute the intent-to treat (ITT) population. Sixty-seven patients (the assessable subgroup) either completed both cycles without a major protocol violation (n = 62) or received a platelet transfusion before treatment was discontinued after the first cycle. In the ITT population, rhIL-11 significantly decreased the requirement for platelet transfusions; 27 of 40 (68%) patients who received rhIL-11 did not require transfusions, compared with 15 of 37 (41%) in the placebo group (P = .04). Treatment with rhIL-11 significantly reduced the total number of platelet transfusions required in the assessable subgroup (P = .03) and the time to platelet recovery to more than 50,000/microL in the second cycle (P = .01). Most adverse events associated with rhIL-11 were reversible, mild to moderate in severity, and likely related to fluid retention. CONCLUSION: rhIL-11 is safe and effective in reducing treatment-associated thrombocytopenia and the need for platelet transfusions in patients who undergo dose-intensive chemotherapy, and thus may permit chemotherapy to be administered as planned at intended doses and thereby maximize the potential for a successful outcome. PMID- 9363867 TI - High-titer HER-2/neu protein-specific antibody can be detected in patients with early-stage breast cancer. AB - PURPOSE: To evaluate HER-2/neu-specific antibody immunity in patients with breast cancer, to determine the rate of occurrence of serum antibodies to HER-2/neu in patients with breast cancer, and to relate the presence of specific immunity to overexpression of HER-2/neu protein in primary tumor. METHODS: The antibody response to HER-2/neu protein was analyzed in 107 newly diagnosed breast cancer patients. Sera was analyzed for the presence of HER-2/neu-specific antibodies with a capture enzyme-linked immunosorbent assay (ELISA) and verified by Western blot. Sera from 200 volunteer blood donors was used as a control population. RESULTS: The presence of antibodies to HER-2/neu correlated with the presence of breast cancer. HER-2/neu antibodies at titers of > or = 1:100 were detected in 12 of 107 (11%) breast cancer patients versus none of 200 (0%) normal controls (P < .01). The presence of antibodies to HER-2/neu also correlated to overexpression of HER-2/neu protein in the patient's primary tumor. Nine of 44 (20%) patients with HER-2/neu-positive tumors had HER-2/neu-specific antibodies, whereas three of 63 (5%) patients with HER-2/neu-negative tumors had antibodies (P = .03). The antibody responses could be substantial. Titers of greater than 1:5,000 were detected in five of 107 (5%). CONCLUSION: The presence of HER-2/neu antibodies in breast cancer patients and the correlation with HER-2/neu-positive cancer implies that immunity to HER-2/neu develops as a result of exposure of patients to HER 2/neu protein expressed by their own cancer. These findings should stimulate further studies to develop the detection of immunity to oncogenic proteins as tumor markers, as well as the development and testing of vaccine strategies to induce and augment immunity to HER-2/neu for the treatment of breast cancer or prevention of recurrent disease. PMID- 9363870 TI - Lung cancer metastatic cells detected in blood by reverse transcriptase polymerase chain reaction and dot-blot analysis. AB - PURPOSE: We analyzed the blood of patients with lung cancer at different stages of presentation for the presence of carcinoembryonic antigen (CEA) mRNA detected by reverse transcriptase-polymerase chain reaction (RT-PCR) combined with the dot blot procedure as an indicator of micrometastatic malignant cells. PATIENTS AND METHODS: We studied 24 lung cancer patients (10 with distant metastases and 14 with no evidence of distant metastases), eight age- and sex-matched patients affected by nonneoplastic respiratory diseases (four smokers), and eight healthy subjects. We used immunohistochemistry and RT-PCR dot-blot analysis to evaluate CEA expression in the neoplastic tissue, and the RT-PCR dot-blot procedure to analyze CEA mRNA in circulating cells. RESULTS: The RT-PCR dot-blot procedure was highly sensitive aspecific: it detected CEA mRNA in samples of RNA from lung cancer diluted 10(6)-fold with RNA extracted from normal blood cells, and sequence analysis confirmed that the amplified product was CEA. CEA mRNA was found in circulating cells from eight of 10 lung cancer patients with distant metastases (diagnostic sensitivity, 80%) and in four of 14 patients with no evidence of distant metastases. Two of the latter had distant metastases within 6 months of analysis. Thus, the diagnostic specificity of the analysis toward lung cancer without distant metastases was 86%. The analysis was negative in the eight nonneoplastic patients and in the eight healthy controls. CONCLUSION: The RT-PCR dot-blot analysis of CEA mRNA in blood cells seems to be a promising tool for the early detection of micrometastatic circulating cells in patients with lung cancer. PMID- 9363869 TI - Randomized trial of chemotherapy and radiation therapy with or without warfarin for limited-stage small-cell lung cancer: a Cancer and Leukemia Group B study. AB - PURPOSE: Studies by the Veterans Administration Cooperative Studies Program and Cancer and Leukemia Group B (CALGB) suggested that the addition of warfarin to chemotherapy might enhance response and/or survival in small-cell lung cancer (SCLC). This randomized study evaluated the effect of warfarin with chemotherapy and radiation therapy in limited-stage SCLC. PATIENTS AND METHODS: Patients were randomized to receive warfarin or no warfarin. All patients received three cycles of doxorubicin, cyclophosphamide, and etoposide (ACE). Cycles 4 and 5 (cisplatin, cyclophosphamide, and etoposide [PCE]) were given concurrently with radiation therapy. Three cycles of ACE were given after chemoradiation therapy, but were discontinued due to a high rate of pulmonary toxicity. RESULTS: There were no significant differences in response rates, survival, failure-free survival, disease-free survival, or patterns of relapse between the warfarin-treated and control groups. In patients treated according to the initial design, an increase in failure-free survival seen with warfarin treatment approached significance (P = .07). Preamendment results, while not significant, did not have superimposable treatment survival curves. A landmark analysis at 8 months showed a median survival time after the landmark for complete responders of 33 months with warfarin treatment compared with < or = 13.75 months for complete or partial responders not treated with warfarin (P = .05). Differences between the complete responders in this preamendment population were not significant (P = .103). CONCLUSION: Warfarin does not appear to improve outcome significantly in limited stage SCLC. However, the differences in some variables between populations before the protocol amendment correspond to the favorable effects of anticoagulants observed in previous studies. PMID- 9363871 TI - Phase II study of single-agent gemcitabine in previously untreated patients with metastatic urothelial cancer. AB - PURPOSE: To determine the activity of single-agent gemcitabine in previously untreated patients with metastatic transitional cell cancer. METHODS: Forty patients with measurable disease and a Karnofsky performance status > or = 60% were enrolled at five institutions between March 1994 and October 1995. Treatment consisted of gemcitabine (1,200 mg/m2) administered weekly times three on a 4 week cycle. One patient was ineligible for response evaluation because pathology review showed a metastatic melanoma. Responses were confirmed by all investigators and an independent radiologist and were maintained for at least 4 weeks. RESULTS: There were four complete and seven partial responses, for an overall response rate of 28%. Responses were seen at all sites, including liver. Median progression-free and overall survival times were 20 and 54 weeks, respectively. Toxicity was mild, with only two grade 4 toxicities. Twenty-five percent of patients experienced grade 3 neutropenia or thrombocytopenia that was rapidly reversible. CONCLUSION: Gemcitabine exhibits significant activity in metastatic transitional cell cancer with minimal toxicity, but survival remains short. Trials of gemcitabine in combination with other active agents are thus suggested. PMID- 9363872 TI - Comparison of toxicity and survival following intraperitoneal recombinant interleukin-2 for persistent ovarian cancer after platinum: twenty-four-hour versus 7-day infusion. AB - PURPOSE: To compare the toxicity, pharmacokinetics, and efficacy seen in ovarian cancer patients treated with escalating doses of intraperitoneal (I.P.) interleukin-2 (IL-2) by two different infusion schedules. PATIENTS AND METHODS: Forty-five patients were sequentially entered onto a phase I/II study in groups of four at fixed dosage tiers of 6 x 10(4), 6 x 10(5), 6 x 10(6), and 3 x 10(7) IU/m2/d in either of two schedules: (A) intermittent weekly infusions of 24 hours' duration; or (B) alternating continuous 7-day infusions followed by 7-day intervals without therapy. Eligibility criteria included > or = six courses of prior platinum-based chemotherapy and laparotomy-confirmed persistent or recurrent ovarian cancer. RESULTS: Forty-one eligible patients received I.P. IL-2 and were assessable for toxicity, but six patients were not assessable for response, which left 35 patients assessable for response. Significant locoregional dose-limiting toxicity was seen with the 7-day infusions (including bowel perforation), with 600,000 IU/m2 as the maximum-tolerated dose (MTD), but catheter infection was the only significant complication seen with the 24-hour infusions, for which an MTD was not established. Among 35 assessable patients, there were six laparotomy-confirmed complete responses (CRs) and three partial responses, for an overall response rate of 25.7% (nine of 35). The median survival time of the cohort was 13.7 months and the overall 5-year survival probability was 13.9%. For the nine patients who demonstrated responses (six on the 24-hour infusion and three on the 7-day infusion), the median survival time has not been reached (range, 27 to 90+ months). CONCLUSION: I.P. IL-2 is better tolerated as a weekly infusion as compared with a 7-day infusion and demonstrates evidence of possible long-term efficacy in a modest number of patients. A randomized trial is indicated to determine if the prolonged survival seen in this study is a due to I.P. IL-2 therapy or other factors that cannot be controlled for in a single-arm study. PMID- 9363873 TI - Patterns of care for women with ovarian cancer in the United States. AB - PURPOSE: To characterize treatments for ovarian cancer, to determine if recommended staging and treatment were provided, and to determine factors that influence receipt of recommended staging and treatment. METHODS: A total of 785 women diagnosed with ovarian cancer in 1991 were selected from the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) program. Type and receipt of recommended staging and treatment were examined using data on surgery and physician-verified chemotherapy. RESULTS: Most women with presumptive stage I and II ovarian cancer were treated with surgery alone (58%), while women with stage III or IV disease were treated with surgery plus platinum-based chemotherapy (75% stage III, 56% stage IV). Approximately 10% of women with presumptive stage I and II, 71% with stage III, and 53% with stage IV disease received recommended staging and treatment. The absence of lymphadenectomy and assignment of histologic grade were the primary reasons women with presumptive stage I and II cancer did not receive recommended staging and treatment, whereas for stages III and IV, it was due to older women not receiving surgery plus platinum-based adjuvant chemotherapy. Age, stage, comorbidity, "other" race/ethnicity, and treatment at a facility with an approved residency training program were associated with whether recommended staging and therapy were received. CONCLUSION: Older women with late-stage disease did not receive recommended treatment. The majority of women with early-stage disease did not receive recommended staging and treatment. PMID- 9363874 TI - Criteria for facilities and personnel for the administration of parenteral systemic antineoplastic therapy. Adopted on July 21, 1997 by the American Society of Clinical Oncology. PMID- 9363875 TI - Pancreatic panniculitis. PMID- 9363876 TI - Intensity of surveillance after breast conservation. PMID- 9363877 TI - Salvage treatment of ovarian cancer. PMID- 9363879 TI - Critics claim US inquiry was 'irreparably flawed'. PMID- 9363878 TI - Admission on Gulf War vaccines spurs debate on medical records. PMID- 9363880 TI - Monsanto links up with Millenium on genome research. PMID- 9363881 TI - NIH heads for 7.1 per cent budget growth. PMID- 9363882 TI - Institutes top UK science league table. PMID- 9363884 TI - Ageing. New mice for old questions. PMID- 9363883 TI - How integrins are activated. PMID- 9363885 TI - Evolutionary biology. Sex and synergism. PMID- 9363886 TI - Galileo at Jupiter--meetings with remarkable moons. PMID- 9363887 TI - Of fingers, toes and penises. PMID- 9363888 TI - Chaperoning extended life. PMID- 9363889 TI - Probabilities of conspecificity. PMID- 9363890 TI - Mutation of the mouse klotho gene leads to a syndrome resembling ageing. AB - A new gene, termed klotho, has been identified that is involved in the suppression of several ageing phenotypes. A defect in klotho gene expression in the mouse results in a syndrome that resembles human ageing, including a short lifespan, infertility, arteriosclerosis, skin atrophy, osteoporosis and emphysema. The gene encodes a membrane protein that shares sequence similarity with the beta-glucosidase enzymes. The klotho gene product may function as part of a signalling pathway that regulates ageing in vivo and morbidity in age related diseases. PMID- 9363891 TI - Impaired odour discrimination on desynchronization of odour-encoding neural assemblies. AB - Stimulus-evoked oscillatory synchronization of neural assemblies has been described in the olfactory and visual systems of several vertebrates and invertebrates. In locusts, information about odour identity is contained in the timing of action potentials in an oscillatory population response, suggesting that oscillations may reflect a common reference for messages encoded in time. Although the stimulus-evoked oscillatory phenomenon is reliable, its roles in sensation, perception, memory formation and pattern recognition remain to be demonstrated--a task requiring a behavioural paradigm. Using honeybees, we now demonstrate that odour encoding involves, as it does in locusts, the oscillatory synchronization of assemblies of projection neurons and that this synchronization is also selectively abolished by picrotoxin, an antagonist of the GABA(A) (gamma aminobutyric acid) receptor. By using a behavioural learning paradigm, we show that picrotoxin-induced desynchronization impairs the discrimination of molecularly similar odorants, but not that of dissimilar odorants. It appears, therefore, that oscillatory synchronization of neuronal assemblies is functionally relevant, and essential for fine sensory discrimination. This suggests that oscillatory synchronization and the kind of temporal encoding it affords provide an additional dimension by which the brain could segment spatially overlapping stimulus representations. PMID- 9363892 TI - Prion (PrPSc)-specific epitope defined by a monoclonal antibody. AB - Prions are infectious particles causing transmissible spongiform encephalopathies (TSEs). They consist, at least in part, of an isoform (PrPSc) of the ubiquitous cellular prion protein (PrPC). Conformational differences between PrPC and PrPSc are evident from increased beta-sheet content and protease resistance in PrPSc. Here we describe a monoclonal antibody, 15B3, that can discriminate between the normal and disease-specific forms of PrP. Such an antibody has been long sought as it should be invaluable for characterizing the infectious particle as well as for diagnosis of TSEs such as bovine spongiform encephalopathy (BSE) or Creutzfeldt-Jakob disease (CJD) in humans. 15B3 specifically precipitates bovine, murine or human PrPSc, but not PrPC, suggesting that it recognizes an epitope common to prions from different species. Using immobilized synthetic peptides, we mapped three polypeptide segments in PrP as the 15B3 epitope. In the NMR structure of recombinant mouse PrP, segments 2 and 3 of the 15B3 epitope are near neighbours in space, and segment 1 is located in a different part of the molecule. We discuss models for the PrPSc-specific epitope that ensure close spatial proximity of all three 15B3 segments, either by intermolecular contacts in oligomeric forms of the prion protein or by intramolecular rearrangement. PMID- 9363893 TI - The prostaglandin receptor EP4 triggers remodelling of the cardiovascular system at birth. AB - Survival of newborn placental mammals depends on closure of the ductus arteriosus (DA), an arterial connection in the fetus which directs blood away from the pulmonary circulation and towards the placenta where oxygenation occurs. Here we show that morphological changes resulting in closure of the DA in mice are virtually identical to those observed in larger mammals, including humans, and that maintenance of the DA in the open, or patent, state in fetal mice is dependent on prostaglandin synthesis. This requirement is absent in mice lacking the prostaglandin E2 EP4 receptor (EP4(-/-) mice). In EP4(-/-) mice of the 129 strain, remodelling of the DA fails to occur after birth, resulting in a left-to right shunt of blood and subsequently in death. This suggests that the neonatal drop in prostaglandin E2 that triggers ductal closure is sensed through the EP4 receptor. In contrast, 5% of EP4(-/-) mice of mixed genetic background survive, and selective breeding of these mice leads to a 21% survival rate, suggesting that alleles at other loci can provide an alternative mechanism for ductal closure. PMID- 9363894 TI - Complementation of dominant suppression implicates CD98 in integrin activation. AB - The integrin family of adhesion receptors are involved in cell growth, migration and tumour metastasis. Integrins are heterodimeric proteins composed of an alpha and a beta subunit, each with a large extracellular, a single transmembrane, and a short cytoplasmic domain. The dynamic regulation of integrin affinity for ligands in response to cellular signals is central to integrin function. This process is energy dependent and is mediated through integrin cytoplasmic domains. However, the cellular machinery regulating integrin affinity remains poorly understood. Here we describe a genetic strategy to disentangle integrin signalling pathways. Dominant suppression occurs when overexpression of isolated integrin beta1 cytoplasmic domains blocks integrin activation. Proteins involved in integrin signalling were identified by their capacity to complement dominant suppression in an expression cloning scheme. CD98, an early T-cell activation antigen that associates with functional integrins, was found to regulate integrin activation. Furthermore, antibody-mediated crosslinking of CD98 stimulated beta1 integrin-dependent cell adhesion. These data indicate that CD98 is involved in regulating integrin affinity, and validate an unbiased genetic approach to analysing integrin signalling pathways. PMID- 9363895 TI - Inhibitory and activating functions for MAPK Kss1 in the S. cerevisiae filamentous-growth signalling pathway. AB - Mitogen-activated protein kinase (MAPK) cascades are conserved signalling modules that regulate responses to diverse extracellular stimuli, developmental cues and environmental stresses. A MAPK is phosphorylated and activated by a MAPK kinase (MAPKK), which is activated by an upstream protein kinase, such as Raf, Mos or a MAPKK kinase. Ste7, a MAPKK in the yeast Saccharomyces cerevisiae, is required for two developmental pathways: mating and invasive (filamentous) growth. Kss1 and Fus3, the MAPK targets of Ste7, are required for mating, but their role in invasive growth has been unclear. Because no other S. cerevisiae MAPK has been shown to function in invasive growth, it was proposed that Ste7 may have non-MAPK targets. We show instead that Kss1 is the principal target of Ste7 in the invasive-growth response in both haploids and diploids. We demonstrate further that Kss1 in its inactive form is a potent negative regulator of invasive growth. Ste7 acts to relieve this negative regulation by switching Kss1 from an inhibitor to an activator. These results indicate that this MAPK has a physiologically important function in its unactivated state. Comparison of normal and MAPK deficient cells indicates that nitrogen starvation and activated Ras stimulate filamentous growth through both MAPK-independent and MAPK-dependent means. PMID- 9363896 TI - Switching of the coupling of the beta2-adrenergic receptor to different G proteins by protein kinase A. AB - Many of the G-protein-coupled receptors for hormones that bind to the cell surface can signal to the interior of the cell through several different classes of G protein. For example, although most of the actions of the prototype beta2 adrenergic receptor are mediated through Gs proteins and the cyclic-AMP-dependent protein kinase (PKA) system, beta-adrenergic receptors can also couple to Gi proteins. Here we investigate the mechanism that controls the specificity of this coupling. We show that in HEK293 cells, stimulation of mitogen-activated protein (MAP) kinase by the beta2-adrenergic receptor is mediated by the betagamma subunits of pertussis-toxin-sensitive G proteins through a pathway involving the non-receptor tyrosine kinase c-Src and the G protein Ras. Activation of this pathway by the beta2-adrenergic receptor requires that the receptor be phosphorylated by PKA because it is blocked by H-89, an inhibitor of PKA. Additionally, a mutant of the receptor, which lacks the sites normally phosphorylated by PKA, can activate adenylyl cyclase, the enzyme that generates cAMP, but not MAP kinase. Our results demonstrate that a mechanism previously shown to mediate uncoupling of the beta2-adrenergic receptor from Gs and thus heterologous desensitization (PKA-mediated receptor phosphorylation), also serves to 'switch' coupling of this receptor from Gs to Gi and initiate a new set of signalling events. PMID- 9363898 TI - Peptide bond formation by in vitro selected ribozymes. AB - An attractive solution to the problem of the origin of protein synthesis in an evolving 'RNA world' involves catalysis by nucleic acid without assistance from proteins. Indeed, even the modern ribosome has been considered to be fundamentally an RNA machine, and the large ribosomal subunit can carry out peptidyl transfer in the absence of most of its protein subunits. Successive cycles of in vitro selection and amplification have been used to find RNAs that perform many biochemical reactions, including transfer of an RNA-linked amino acid to their own 5'-amino-modified terminus. Here we demonstrate the in vitro selection of ribozymes (196 nucleotides) that perform the same peptidyl transferase reaction as the ribosome: that is, they can join amino acids by a peptide bond. Like ribosome substrates, one amino acid (N-blocked methionine) is esterified to the 3'(2')-O of adenosine, whereas the acceptor amino acid (phenylalanine) has a free amino group. Our best characterized ribozyme recognizes the amino-acid ester substrate by binding its adenosine moiety, and is therefore capable of utilizing Leu- and Phe- as well as Met-derived substrates. Such lack of specificity with respect to the amino acid is a feature necessary for a generalized protein-synthesizing enzyme. PMID- 9363897 TI - Tyrosine phosphorylation of the EGF receptor by the kinase Jak2 is induced by growth hormone. AB - When growth hormone binds to its receptor, which belongs to the cytokine receptor superfamily, it activates the Janus kinase Jak2 which has tyrosine-kinase activity and initiates an activation of several key intracellular proteins (for example, mitogen-activated protein (MAP) kinases) that eventually execute the biological actions induced by growth hormone, including the expression of particular genes. In contrast to receptors that themselves have tyrosine kinase activity, the signalling pathways leading to MAP kinase activation that are triggered by growth hormone are poorly understood, but appear to be mediated by the proteins Grb2 and Shc. We now show that growth hormone stimulates tyrosine phosphorylation of the receptor for epidermal growth factor (EGFR) and its association with Grb2 and at the same time stimulates MAP kinase activity in liver, an important target tissue of growth hormone. Expression of EGFR and its mutants revealed that growth-hormone-induced activation of MAP kinase and expression of the transcription factor c-fos requires phosphorylation of tyrosines on EGFR, but not its own intrinsic tyrosine-kinase activity. Moreover, tyrosine at residue 1,068 of the EGFR is proposed to be one of the principal phosphorylation sites and Grb2-binding sites stimulated by growth hormone via Jak2. Our results indicate that the role of EGFR in signalling by growth hormone is to be phosphorylated by Jak2, thereby providing docking sites for Grb2 and activating MAP kinases and gene expression, independently of the intrinsic tyrosine kinase activity of EGFR. This may represent a novel cross-talk pathway between the cytokine receptor superfamily and growth factor receptor. PMID- 9363899 TI - High levels of genetic change in rodents of Chernobyl. PMID- 9363901 TI - Human helper and memory lymphocytes exhibit an inducible elastin-laminin receptor. AB - We showed recently that human activated lymphocytes express the elastin-laminin receptor. In this study, we were interested in the kinetics of the induction of this receptor on human activated lymphocytes in vitro and in the quantification of its expression on different human lymphocyte subsets. It appears that the expression of the elastin-laminin receptor is a general property of most activated human lymphocytes but strongly dependent on the lymphocyte subsets. It appeared that the helper (CD4+) and memory (CD45RO+) lymphocytes exhibited the strongest increase of elastin-laminin receptor expression when cultured for 72 h in the presence of 2 microg/ml elastin peptides (2.7x10[-8] M) as compared to control cells. Activation of this receptor by elastin peptides triggers the stimulation of biosynthesis and release of a PMN-like elastase. Activated T lymphocytes (mostly helper and memory T cells) are present from early stages of the atherosclerotic process and this release could contribute to the progression of the lesion by engaging a vicious circle with more elastin peptides released attracting more mononuclear cells and increasing their elastase production. PMID- 9363900 TI - Molecular and cellular biology of mast cells and basophils. AB - In all mammalian species investigated so far, mast cells and basophils are the only cells that synthesize histamine and express plasma membrane receptors that bind IgE with high affinity (Fc epsilonRI). Human basophils and mast cells derive from distinct precursors that originate in the bone marrow and fetal liver and probably circulate in peripheral blood. There is extensive evidence that mast cells and basophils and their mediators are primary effectors of allergic inflammation. Immunologically activated human basophils release two cytokines: IL 4 and IL-13. Expression of several cytokines has been documented in a number of experimental models of human and rodent mast cells. However, to date few studies have analyzed the mechanisms of gene expression in human Fc epsilonRI+ cells. Some of these studies imply a role for NFAT and GATA family members in the IgE mediated activation of cytokine gene transcription in basophils and mast cells. Studies of human basophils and mast cells isolated from different anatomic sites have established the different profiles of eicosanoids released by these cells. Recently, the characterization of arachidonic acid pools and the identification of novel enzymes involved in arachidonate remodeling and mobilization clarified in part how eicosanoid productions is regulated in mast cells and basophils. In addition to histamine, human mast cell secretory granules contain the neutral proteases tryptase, chymase and carboxypeptidase that possess several biochemical properties. In particular, tryptase may play a role as a fibrogenic factor and chymase might convert angiotensin I to angiotensin II. Mast cells are present in human heart and in human coronary arteries raising the possibility that local activation of cardiac mast cells might contribute to certain cardiovascular diseases. Recent evidence also suggests that mast cells and basophils can play a role during viral and bacterial infections. It is now evident that in man these two cells not only participate in inflammation associated with allergic disease, but also in chronic and fibrotic disorders affecting several organs and in host defense against bacterial and viral infections. PMID- 9363902 TI - Streptococcal erythrogenic toxins induce tryptophan degradation in human peripheral blood mononuclear cells. AB - BACKGROUND: In various cells including monocytes the cytokine interferon-gamma as well as lipopolysaccharide induce indoleamine 2,3-dioxygenase which degrades tryptophan to form L-kynurenine. We addressed the question of whether the exposure of human peripheral mononuclear cells to superantigens derived from streptococci is associated with tryptophan degradation in vitro. METHODS: Peripheral blood mononuclear cells were exposed to streptococcal erythrogenic toxins A and B and a streptococcal-derived mitogen named BX. In addition, the myelomonocytic cell line THP-1 was treated with these toxin preparations. RESULTS: In peripheral blood mononuclear cells all three toxins induced tryptophan degradation. In parallel, production of interferon-gamma was found, and the tryptophan degradation could be blocked by antihuman interferon-gamma antibodies. Tryptophan degradation was not induced when the human myelocytoma cell line THP-1 was stimulated with these toxins, but there was a costimulatoty effect to interferon-gamma. CONCLUSIONS: In peripheral blood mononuclear cell culture streptococcal erythrogenic toxins are able to stimulate tryptophan degradation in humans via the induction of interferon-gamma production. There seems to be no direct effect on myelomonocytic THP-1 cells. Because some of the degradation products of tryptophan, such as quinolinic acid and kynurenic acid, are toxic, superantigen-driven degradation oftryptophan may play a role for example in the development of the toxic-shock-like syndrome associated with severe group A streptococcal infections. PMID- 9363903 TI - Molecular cloning and expression of cynomolgus monkey interferon-gamma cDNA. AB - Since the discovery of its involvement in the pathogenesis of simian immunodeficiency virus infection, the role of macaque monkey interferon-gamma (IFNgamma) has been a focus of particular interest. The purpose of this study was to express bioactive recombinant monkey IFNgamma, as well as clone cynomolgus monkey IFNgamma cDNA. The isolation of a cDNA encoding cynomolgus monkey IFNgamma was performed using a reverse transcriptase polymerase chain reaction-based strategy with activated monkey lymphocyte cDNA as templates. Cynomolgus monkey IFNgamma consists of 165 amino acids including a putative signal sequence and has 94, 60 and 39% identity to human, bovine and murine homolgues, respectively. Monkey IFNgamma cDNA was highly expressed as three distinct secreted proteins by a recombinant baculovirus system. The secreted proteins were revealed to have antiviral activity up to 10(8) units/ml characteristic of authentic IFNgamma by a bioassay of a cytopathic effect reduction assay. PMID- 9363904 TI - IL-4 and IL-6 production of bone marrow-derived mast cells is enhanced by treatment with environmental pollutants. AB - To examine the potential effects of environmental pollutants on the production of cytokines in mast cells, mouse bone marrow-derived mast cells (BMMC) were cultured at various concentrations of diesel exhaust particulates (DEP) or formaldeyhde. Proliferation of BMMC at 0.8, 2 and 4 microg/ml of DEP and 0.5 and 1 microg/ml of formaldehyde did not differ significantly from that of the controls (0 microg/ml) after 72 h culture, with the exception of a significant decrease in proliferation at 5 microg/ml of formaldehyde. Treatment with DEP or formaldehyde alone did not induce interleukin-4 (IL-4) or IL-6 production by BMMC. IL-4 and IL-6 production in BMMC stimulated with A23187 was higher in BMMC treated with low concentrations of DEP than in controls, but no increase was seen in BMMC treated with high DEP. IL-4 and IL-6 production in A23187-stimulated BMMC was significantly increased at 0.5 and 1 microg/ml formaldehyde but decreased at 5 microg/ml formaldehyde. After pretreatment with low DEP or formaldehyde alone for 24h, IL-4 production of BMMC stimulated with A23187 was lower in BMMC treated with low DEP or formaldehyde than in controls. Antigen-induced IL-4 production significantly increased in BMMC treated with 0.4 or 0.8 microg/ml DEP or 0.5 microg/ml formaldehyde, but antigen-induced IL-6 production in BMMC did not increase at low DEP or formaldehyde. Although the enhancement of IL-4 production of BMMC stimulated with A23187 plus DEP was not completely inhibited by 5x10(-4) M 2-mercaptoethanol (2-ME), treatment with 10(-7) M dexamethasone inhibited further IL-4 production. Cytokine production of mast cells is thus shown here for the first time to be modulated by treatment with DEP or formaldehyde. Environmental pollutants such as DEP and formaldehyde may thus affect the immune response via the modulation of cytokine production in mast cells. PMID- 9363905 TI - Salivary anti-hsp65 antibodies as a diagnostic marker for gingivitis and a possible link to atherosclerosis. AB - Levels of specific salivary IgA antibodies against mycobacterial heat shock protein (hsp) 65 are significantly increased in patients with gingivitis when compared to clinically healthy subjects. The process of identifying the hsp65 epitopes recognized by the salivary antibodies, binding to overlapping 15-mer hsp65 peptides, was assessed. Time-resolved fluorescence immunoassays using 15 mer overlapping peptides spanning the whole hsp65 molecule revealed six distinct sequences recognized by anti-hsp65 IgA antibodies. Due to the high degree of sequence homology between mycobacterial hsp65, cognates of the hsp60 family of oral bacterial flora and human hsp60, these six epitopes may serve as cross reactive autoantigens in certain circumstances in vivo and could incite an autoimmune response that contributes to the initiation of gingivitis. PMID- 9363906 TI - Immunobiochemical characterization of Putranjiva roxburghii pollen extract and cross-reactivity with Ricinus communis. AB - Putranjiva roxburghii (PR) pollen has been found to be an important aeroallergen for type I hypersensitivity. In the present study, the IgE binding proteins of PR pollen have been characterized and compared with pollen allergens of Ricinus communis (RC) belonging to family Euphorbiaceae. On isoelectric focusing, PR pollen extract resolved into 35 bands (pI 3-9), whereas SDS-PAGE separated it into 18 protein components (MW 14-100 kD). Pooled patient's sera (ID +ve to PR) recognized 12 allergenic proteins in Putranjiva and five of them (MWs 92, 80, 55, 43 and 30 kD) showed immunologic reactivity to most of the sera samples tested individually by immunoblot. A number of shared allergenic proteins (MWs 92, 80, 66, 50, 43 and 14 kD) were observed between PR and RC pollen extracts on immunoblot using Putranjiva allergic serum pool. Inhibition in the binding for most of PR pollen allergenic proteins was obtained with higher concentration of RC extract than PR itself, depicting the presence of cross-reacting allergens in both. Putranjiva pollen extract was fractionated by a combination of DEAE Sephadex-A 50 and Sephadex-G 200 column chromatography. Periodate deglycosylation of western blotted PR extract and Put I fraction indicated the involvement of carbohydrate moieties in the allergenic activity. Of the two fractions from Put I (Ia and Ib), Put Ib was found to be the most allergenic protein by ELISA inhibition. Dot blot analysis with individual patients sera identified it as a major allergen of PR. PMID- 9363907 TI - Using monoclonal antibodies to characterize a sequential epitope on the group I allergen of Bermuda grass pollen. AB - BACKGROUND: Cyn d 1, the group I allergen of Bermuda grass pollen, had been purified and characterized. METHODS: A sequential B cell epitope on Cyn d 1 was studied with monoclonal antibodies (MoAbs). Cyn d 1 was cleaved by Achromobacter protease I into fragments, and the resulting peptides were fractionated on reversed-phase columns before being reacted with anti-Cyn d 1 MoAbs in a radioimmunoassay. A Cyn d 1 fragment recognized by its MoAb was selected for Edman degradation. A synthetic peptide was constructed according to the determined sequence. RESULTS: The epitope on Cyn d 1 recognized by MoAb 18-53 was found to be conformation independent, since its activity was not changed after sodium periodate, guanidine or urea treatment. The enzyme-cleaved fragment containing this epitope was determined to be DVDKPPFDGMTACGNEPIF which corresponds to the N-terminal 46-64 residues of Cyn d 1. The presence of this sequence in the epitope recognized by MoAb 18-53 was demonstrated by enzyme immunoassay and further confirmed by inhibition of binding enzyme immunoassay with synthetic peptides. Some cross-reactivity with the N-terminal 45-63 residues of Lol p 1 was also found. CONCLUSIONS: The primary structure of a sequential epitope on Cyn d 1 was determined, and its activity was confirmed with peptides synthesized according to the determined sequence. PMID- 9363908 TI - Identification of a Ca2+ binding protein as a new Bermuda grass pollen allergen Cyn d 7: IgE cross-reactivity with oilseed rape pollen allergen Bra r 1. AB - cDNA clones encoding two isoforms of an allergen from pollen of Bermuda grass (Cynodon dactylon) have been isolated using IgE from allergic patients. Homologous transcripts are present in pollen of 15 other grasses tested. This allergen, tentatively designated as Cyn d 7, contains two calcium binding domains and shows significant sequence similarity with other Ca2+ binding pollen allergens, namely Bet v 4 from birch and Bra r 1 from oilseed rape. Approximately 10% of allergic sera tested showed IgE reactivity to this allergen. IgE cross reactivity was observed between this allergen and Bra r 1 of oilseed rape. IgE reactivity of this allergen requires protein-bound Ca2+. Using IgE affinity purified from the recombinant allergen to probe Western blots of pollen extracts Cyn d 7 has been identified as a 12 kDA protein. PMID- 9363909 TI - Heterogeneity in the polyclonal T cell response to birch pollen allergens. AB - BACKGROUND: Immunodominant epitopes of Bet v 1a had been identified before, using recombinant (r) Bet v 1a-reactive T cell clones generated from peripheral blood mononuclear cells of patients allergic to birch pollen. This study aimed at evaluating the T cell-stimulating capacity of immunodominant Bet v 1a-derived peptides in a polyclonal system corresponding more closely to the situation in patients. METHODS: Short-term T cell lines (TCL) were established in presence of a protein extract of birch pollen (BP extract). TCL proliferation induced by the BP extract, by natural Bet v 1, rBet v 1a, rBet v 2 or 5 selected immunodominant Bet v 1a-derived peptides was determined. RESULTS: Consistent with the knowledge that Bet v 1 is the major IgE-binding allergen of birch pollen, we found comparable T cell reactivity to natural Bet v 1 and the BP extract within the majority of the TCL. Accordingly, the response to rBet v 2 was low compared with the reactivity to the BP extract. The response of the TCL to rBet v 1a proved to be highly heterogeneous. Furthermore, the TCL response to the 5 immunodominant Bet v 1a-derived peptides showed considerable diversity. The proliferative responses of most TCL (with one exception) following stimulation by these peptides were low, in relation to the expansion induced by the BP extract. CONCLUSION: These findings argue against the use of selected peptides derived from Bet v 1a in specific immunotherapy of patients with birch allergy. PMID- 9363910 TI - Measurement of airborne flour exposure with a monoclonal antibody-based immunoassay. AB - BACKGROUND: The development of simple and standardised methods to measure airborne levels of workplace biological allergens is an important step in reducing the incidence of occupational asthma. Such a method would be useful for measuring wheat flour allergens which cause asthma in bakers. Measurement of allergen per se rather than total dust enables exposure to be better defined. METHODS: Monoclonal antibodies were produced, their specificity analysed by immunoblotting and then used to affinity-purify a putative flour allergen. The importance of this protein as an allergen was tested by RAST using sera from allergic bakers and it was identified by N-terminal sequencing. Suitable monoclonal antibodies were chosen to develop an enzyme-linked immunosorbent assay. Commercial baking flours and personal airborne dust samples were analysed using the immunoassay. RESULTS: A sensitive and specific monoclonal antibody based enzyme-linked immunosorbent assay was developed to measure a wheat alpha amylase inhibitor. The wheat alpha-amylase inhibitor content of bulk wheat flours was 0.124% (95% confidence limits 0.083-0.164%) and airborne levels in bakeries had a geometric mean of 744 ng/m3 (95% confidence limits 371-1,496 ng/m3). CONCLUSION: This assay is suitable for widespread use as the monoclonal antibodies and standards are well defined and potentially infinitely available. The assay therefore offers distinct advantages over those exposure assessment methods currently in use. Comparable results would be obtained by different investigators over a prolonged time period. The assessment of flour allergen exposure and the relationship with clinical response could then be investigated using a multi-centered approach. PMID- 9363911 TI - The effect of azelastine on the infiltration of inflammatory cells into the bronchial mucosa and clinical changes in patients with bronchial asthma. AB - BACKGROUND: Azelastine is an oral antiallergic compound but there is no direct evidence of its anti-inflammatory actions in bronchial asthma. We examined the effect of azelastine on inflammatory cells infiltrating the bronchial mucosa and clinical symptoms in atopic asthma in a double-blind, parallel, randomized study. METHODS: The study was completed by 13 subjects in the azelastine (4 mg/day) group and 11 subjects in the placebo group. Treatments were randomly administered for 3 months. Each subject recorded daily asthma symptoms and peak expiratory flow (PEF). Lung function and bronchial responsiveness to methacholine were measured before and after treatment. Fiberoptic bronchoscopy was performed and bronchial biopsies taken from segmental carinae before and after treatment with azelastine or placebo. Using each monoclonal antibody for eosinophils, mast cells, macrophages, and T lymphocytes we performed immunohistological staining on biopsy specimens. RESULTS: Compared with the placebo-treated group, the azelastine-treated group exhibited significant improvement of asthma symptoms (p<0.01), PEF (p<0.01), PEF diurnal variation (p<0.001), excluding forced expiratory volume in 1 s or airway responsiveness. This was accompanied by a reduction of EG2(+) eosinophils (p<0.01), CD3(+) (p<0.001), CD4(+) (p<0.05), CD8(+) (p<0.05) T lymphocytes, and CD25(+)-activated T lymphocytes (p<0.001) in the bronchial mucosa. Significant correlations were found between clinical data and immunohistochemical parameters. CONCLUSION: These results demonstrated that the beneficial effects ofazelastine in bronchial asthma may result from modulation of local bronchial inflammatory cell infiltration. PMID- 9363912 TI - Protection against verocytotoxin in mice induced by liposome-coupled verocytotoxin. AB - Purified verocytotoxins (VTs), VT1 and VT2, were coupled to liposomes via glutaraldehyde. During the coupling procedure, both VT1 and VT2 were detoxified. Intraperitoneal injection in BALB/c mice with either VT1-liposome or VT2-liposome induced a substantial amount of anti-VT1 or anti-VT2 IgG antibody production, respectively. Mice immunized with VT2-liposome were protected against intravenous challenge with a lethal dose of VT2 and the degree of protection correlated well with the amount of IgG induced against VT2. Although VT1-liposome failed to induce protection against VT1, the decrease of the body weight observed after the toxin challenge correlated inversely with the amount of anti-VT1 IgG induced, suggesting that VT1 neutralizing antibody was present in VT1-liposome-immune mice. In addition, VT-liposome conjugate induced no detectable anti-VT IgE antibody production. These results demonstrate the potential ability of VT liposome conjugates for the production of VT vaccine which induces protection against VTs. PMID- 9363913 TI - Contact allergy to henna. AB - Vegetable dyes can be recommended to patients sensitized to oxidative dyes due to their low allergenic power. The most important of these is henna which is used as a reddishbrown hair dye in some parts of the world. Different pathologies have been described caused by henna but the incidence of contact dermatitis appears to be extremely rare. In the present paper, we describe the case of a 30-year-old woman who developed allergic contact dermatitis following application of henna, but who did not work with the dye professionally. PMID- 9363914 TI - FK506 enhances IL-13 production by T cells activated through CD3/CD28. PMID- 9363915 TI - Induction of eosinophil chemotactic factor production from human peripheral blood mononuclear cells by solubilized BALL-1, a B cell lymphoma line. AB - We have previously shown that irradiated BALL-1, a B lymphoma line, stimulates OKT4 T cells to produce a unique eosinophil chemotactic factor (ECF) which suppresses the respiratory burst of eosinophils. In the present experiments, we found that solubilized BALL-1 also stimulated peripheral blood mononuclear cells (PBMC) to produce ECF activity in a dose-dependent manner. PBMC treated with solubilized BALL-1 produced ECF within 24 h. ECF production-inducing factor (ECF IF) had affinity with lentil lectin beads, suggesting that ECF-IF has glucose or mannose as carbohydrate moieties. Furthermore, we found that ECF-IF activity was comprised of at least four ECF-IF with different isoelectric points (pI): ECF-IF1 had a pI of 4-5, ECF-IF2 a pI of about 6, ECF-IF3 a pI of about 7, and ECF-IF4 a pI of about 8. ECF-IF1 stimulated PBMC to produce mainly an ECF with a pI of about 7-8, whereas the rest of ECF-IF induced an ECF with a different pI. The present results suggest that the membrane glycoproteins of some tumors, at least, partly contribute to tissue eosinophilia in the stroma of the malignant tumor by inducing ECF production from PBMC. PMID- 9363916 TI - Effects of IL-4 on antigen-induced production of eosinophil chemotactic activity from human mononuclear leukocytes. AB - The effect of IL-4 on antigen-induced production of eosinophil chemotactic factors (ECF) from human peripheral blood mononuclear cells (PBMC) was examined. Antigen-induced ECF production was enhanced in a dose-dependent manner when PBMC were pretreated with IL-4. The most potent enhancement was induced by IL-4 at a concentration of 30 U in tuberculin-sensitive PBMC, and 3 U in Dermatophagoides farinae (Df)-sensitive PBMC. A short period of pretreatment (30 min to 3 h) was sufficient for the enhancement, whereas a longer period of treatment was less effective. IL-4 pretreatment suppressed PPD-induced IFNgamma and IL-5 production but enhanced ECF production. Furthermore, we found that Df induced IL-5 but not IFNgamma production from PBMC, and that IL-5 production was not affected by pretreatment with IL-4. Next, experiments were done to clarify whether the ECF produced by PPD-stimulated PBMC was different from that produced by Df-stimulated PBMC. It was thus found that the pI of both ECF was at about pH 7.0 and that unlike chemokines such as RANTES and eotaxin, they had no affinity for heparin. PMID- 9363917 TI - Development of lung eosinophilic inflammation by the infusion of IL-5-producing T cell clones. AB - To delineate the critical role of T cells on asthma, we tested whether eosinophilic inflammation of the bronchial mucosa is induced by transfer of IL-5 producing T cell clones, in the absence of antigen-specific immunoglobulins (IgE, A and G). Ovalbumin-specific T cell clone, FI5, that produced IL-5 upon challenge with relevant antigen was established. Eosinophilic inflammation of the lung occurred when unprimed mice were transferred with FI5 and challenged by the inhaled antigen. Eosinophil infiltration was completely suppressed by the administration of anti-IL-5 neutralizing antibody, indicating the essential role of IL-5. We concluded that the existence of IL-5-producing helper T cells is sufficient for the development of airway eosinophilic inflammation. PMID- 9363918 TI - Role of tyrosine kinases in human eosinophil degranulation. AB - Degranulation of eosinophils and subsequent release of toxic granule proteins play a key role in allergic diseases such as bronchial asthma. However, little is known about the intracellular signaling mechanism of eosinophil degranulation. In this report, we investigated the role of protein tyrosine kinases (PTK) in the degranulation of human peripheral blood eosinophils. Stimulation of eosinophils with Sepharose beads coated with secretory IgA (sIgA) or IgG triggered the phosphorylation of tyrosine residues in several proteins, including 50-65, 73, 78, 100, 105 and 113 kD. In addition, IgG-coated beads induced a rapid increase in the tyrosine kinase activity of src-like PTK, Fgr. The tyrosine kinase inhibitors, genistein and herbimycin A, inhibited both the tyrosine phosphorylation and degranulation responses of eosinophils induced by sIgA- or IgG-coated beads. In contrast, eosinophil degranulation induced by phorbol myristate acetate was not affected by genistein. These findings suggest that a PTK-dependent signaling pathway plays an important role in triggering the eosinophil degranulation induced by immobilized immunoglobulin. PMID- 9363919 TI - 65-kilodalton protein phosphorylation in human peripheral blood eosinophils. AB - To evaluate the presence of protein phosphorylation in peripheral blood eosinophils, venous blood was drawn from normal healthy volunteers. Eosinophils were isolated on a Percoll gradient and were incubated with [gamma32P]ATP in the presence of Mg2+. After stopping the reaction, SDS-PAGE was performed and autoradiographs were prepared to determine the incorporation of 32P into proteins. Eosinophils developed at least 24 protein bands below 116.25 kD by SDS PAGE. In the autoradiographs, one distinct radioactive band was observed with a molecular weight of 65 kD. 32P incorporation into the 65-kD band was dependent on Mg2+ concentration and maximal response was observed at concentrations of 2-6 mM MgCl2. 32P incorporation into the band was dependent on the reaction time and temperature of the reaction system. Acid hydrolysis showed that [32P]phosphate radioactivity in the cells was present primarily as phosphoserine, indicating the presence of 65-kD protein phosphorylation in human peripheral blood eosinophils. PMID- 9363920 TI - The activation of the JAK2/STAT5 pathway is commonly involved in signaling through the human IL-5 receptor. AB - The JAK (Janus kinase) family of protein tyrosine kinases and the STATs (signal transducers and activators of transcription) have been shown to be activated in response to a number of cytokines and growth factors. In this study, we evaluated the activation of JAK/STAT pathway upon human interleukin-5 (hIL-5) stimulation of two different hIL-5-responsive cell lines, hIL-5 receptor alpha-subunit (hIL 5R alpha) cDNA-transfected TF-1 (TF-h5R alpha) and butyric-acid-treated YY-1 (YY Bu), and peripheral eosinophils. Immunoprecipitation and electrophoretic mobility shift analysis revealed that tyrosine phosphorylation of JAK2 and activation of STAT5 were induced upon stimulation with hIL-5 in all three cell types, while STAT1 activation was only observed in eosinophils. These results indicate that JAK2/STAT5 activation is a common JAK/STAT pathway for hIL-5-mediated signal in these cells. PMID- 9363922 TI - Expression of mRNA for RANTES in human eosinophils. AB - RANTES has been considered to play an important role in various immune and allergic disorders since RANTES is a potent chemoattractant for various important inflammatory cells such as eosinophils. Eosinophils, on the other hand, are considered to be the major inflammatory cells in bronchial asthma since eosinophil-specific granule proteins can damage bronchial mucosal cells. The recent demonstration that eosinophils themselves could synthesize some cytokines such as IL-5 indicates the role of these cytokines not only in paracrine but also in autocrine regulation of eosinophil production, differentiation and activation. Therefore, in this study, we examined mRNA for RANTES and release of RANTES by human eosinophils. The present findings revealed that eosinophils obtained from asthmatic patients could express and release RANTES. Taken together, these findings suggest that eosinophils play a crucial role in the pathogenesis, particularly in eosinophil and T lymphocyte recruitment into the inflamed sites in asthma through RANTES production. PMID- 9363921 TI - Enhanced production of RANTES, an eosinophil chemoattractant factor, by cytokine stimulated epidermal keratinocytes. AB - In allergic skin diseases such as atopic dermatitis (AD), eosinophils migrate from the circulation to the skin. We investigated the mechanisms of eosinophil chemotaxis in atopic dermatitis by examining the effect of stimulation of epidermal keratinocytes (KC) by inflammatory cytokines, interferon-gamma (IFNgamma) and/or tumor necrosis factor-alpha (TNF alpha) on the production of eosinophil chemotactic factors. Simultaneous addition of IFNgamma and TNF alpha to culture KC synergistically increased eosinophil chemotaxis and the expression of RANTES mRNA and protein level on these cells. Anti-RANTES antibody blocked eosinophil chemotaxis by IFNgamma- and TNF alpha-stimulated KC. Our results indicate that the production of RANTES by KC may help to explain eosinophil infiltration into the skin in AD. PMID- 9363923 TI - Production of IL-8 and release of eosinophil-derived neurotoxin by normal peripheral blood eosinophils. AB - To study the regulation of IL-8 production and release of eosinophil-derived neurotoxin (EDN) by normal blood eosinophils, we isolated eosinophils from healthy individuals and stimulated them with immobilized secretory IgA with or without exogenous IL-5 for 3, 12, and 24 h, and with different concentrations of ionomycin for 24 h. Eosinophils cultured with secretory IgA for 3 and 12 h showed strong expression of mRNA for IL-8 by reverse transcription polymerase chain reaction. Exogenous IL-5 enhanced mRNA for IL-8 expression by eosinophils after 24 h of incubation. IL-8 secretion increased in a time-dependent manner throughout the 24 h of observation; in contrast, EDN release reached a plateau value after 12 h. Furthermore, at least 2 microM ionomycin was necessary for induction of IL-8 secretion, whereas 0.5 microM induced detectable EDN release by eosinophils. These results suggest that the mechanism of eosinophil degranulation may be different from those of cytokine secretion. PMID- 9363924 TI - Comparative studies on schistosomulicidal activity of mouse and rat eosinophils. AB - Eosinophils from interleukin (IL)-5 transgenic mice were shown to have antibody dependent killing activity against the larvae of Schistosoma japonicum. However, in comparison with rat eosinophils, the schistosomulicidal activity of mouse eosinophils was lower. Flow cytometric analysis of the cells binding to mouse immunoglobulins demonstrated that rat cells were superior to mouse cells in the binding of mouse IgG. However, the adherence and schistosomulicidal activity of mouse cells were inhibited by rat anti-mouse Fcgamma receptor monoclonal antibody. These results suggest that the mechanism of killing by mouse eosinophils is mediated by IgG antibodies. PMID- 9363925 TI - Protective roles of eosinophils in Nippostrongylus brasiliensis infection. AB - Nippostrongylus brasiliensis infection is characterized by blood and tissue eosinophilia induced by interleukin (IL)-5 secreted from CD4+ T cells. However, it is still obscure whether eosinophils play an important role in the protection against N. brasiliensis infection. In this study we attempted to determine whether the in vivo environment of IL-5 transgenic mice, characterized by high eosinophil production, could affect the worm burden after N. brasiliensis infection. Kinetic studies on the infection demonstrated a significantly lower worm recovery from the intestine of IL-5 transgenic mice compared to age-matched background controls. This tendency was also observed at the lung stage of the infection. Furthermore, with respect to elevation of the serum IgE concentration, the peak level was observed at 2 weeks after infection in infected background control mice with four times higher concentrations than those of uninfected mice. In contrast, the increase of IgE concentration in IL-5 transgenic mice was very limited and low. The adoptive transfer of eosinophils from IL-5 transgenic mice into background control animals resulted in the reduction of worm recovery from the lungs, suggesting that eosinophils play a key role in the protection against migrating larvae of N. brasiliensis. These results indicate that the innate high level of eosinophils due to constitutive production of IL-5 augments immunity against N. brasiliensis infection. PMID- 9363926 TI - Steroid-induced changes of eosinophils in atopic dermatitis. AB - We investigated whether apoptosis of eosinophils is specific to atopic dermatitis (AD), or also occurs in other diseases with eosinophilia. We examined the survival of eosinophils cultured with corticosteroids: (1) Clinically, steroid administration significantly decreased high peripheral blood eosinophil cell counts in patients with AD. (2) Treatment with recombinant human (rh) IL-5 prolonged the life span of eosinophils derived from patients with AD and of those derived from non-AD patients with eosinophilia. However, there were differences in the survival rates in the presence of rhIL-5: the eosinophils from non-AD patients showed 1.4-fold higher survival rates than those from AD patients at 24 h. In the presence of steroids, the eosinophils from non-AD patients showed a survival rate double that of those from AD patients at 24 h. (3) In eosinophils from patients with AD, the survival rate decreased significantly in a time- and steroid-concentration-dependent manner. Steroid administration significantly inhibited the survival rate of eosinophils from patients with AD compared to those of monocytes and neutrophils. These findings suggest that apoptosis induced by steroids decreases the eosinophil count in vivo in patients with AD. There may be a difference in the incidence of steroid-induced apoptosis between eosinophil cells from patients with AD and those from patients with eosinophilia due to other underlying diseases. PMID- 9363927 TI - Serum levels of eosinophil cationic protein and IL-5 in patients with asthma without systemic corticosteroids. AB - We measured the serum levels of eosinophil cationic protein (ECP) and interleukin 5 (IL-5) in 39 patients with asthma (symptomatic 12, asymtomatic 27) without systemic corticosteroids and 49 healthy subjects. There were significant differences in serum levels in both ECP and IL-5 between symptomatic and asymptomatic asthma, and healthy subjects. A significant positive correlation was found between serum levels of ECP and IL-5. No significant correlation was found between %FEV1 and serum level of ECP or IL-5, however, when the analysis was restricted to patients of less than 60 years of age, the correlations were significant. These results suggest that IL-5 is one of the factors that activate eosinophils even in peripheral blood, and that measurement of serum levels of ECP and IL-5 is useful for in vitro monitoring of asthma. PMID- 9363928 TI - Comparison of platelet-activating factor receptor mRNA levels in peripheral blood eosinophils from normal subjects and atopic asthmatic patients. AB - Platelet-activating factor (PAF) modulates the functions of eosinophils, which play an important role in allergic inflammation, through a specific receptor(s) expressed on the cell surface. We compared expression levels of mRNA for the PAF receptor (PAF-R) in peripheral blood eosinophils from atopic asthmatic patients with those from normal healthy subjects using a relative quantification method based on the reverse transcription-polymerase chain reaction (RT-PCR). We found that the levels of PAF-R mRNA in eosinophils from the patients were significantly higher than those in normal subjects. These results suggest that the increased expression of PAF-R in eosinophils may be relevant to the pathogenesis of atopic asthma. PMID- 9363929 TI - Expression of apoptosis-related antigen on eosinophils in chronic eosinophilic pneumonia. AB - We examined the expression of apoptosis-related antigens Fas and bcl-2 on eosinophils from peripheral blood (PB) and bronchoalveolar lavage (BAL) in patients with chronic eosinophilic pneumonia (CEP). The expression of those antigens was assessed before and after culture with or without eosinophil chemotactic factors derived from an established T-cell line (STO-2-derived ECFs; ECF-PI5, 6, 7, 8, and 9), granulocyte-macrophage colony stimulating factor, and interleukin 5 (IL-5). We found that the expression of these antigens on eosinophils from PB increased after 24 h culture without any stimulation. In contrast, little or no change was observed even after 24 h culture in eosinophils from BAL. All STO2-derived ECFs and IL-5 suppressed Fas expression on eosinophils from PB. Furthermore, we found that eosinophils which were attracted by ECF-PI9 expressed Fas and bcl-2 more highly than those attracted by other ECFs and IL-5. Such a heterogeneous response of eosinophils to respective ECFs suggests the possibility of a heterogeneous population of eosinophils in patients with CEP. PMID- 9363930 TI - CD44 expression on blood eosinophils is a novel marker of bronchial asthma. AB - Bronchial asthma is characterized by infiltration of the respiratory tracts by eosinophils. A wide variety of adhesion molecules expressed by eosinophils have been proposed to be involved in binding of eosinophils to the vascular endothelium and subsequent transmigration from the circulation to the airways, while little is known about CD44 expression on eosinophils. We introduced a novel staining combination with which surface markers on eosinophils could be analyzed without purification prior to staining, and examined the expression of CD44 on eosinophils. Staining of eosinophils with anti-CD 16 and anti-VLA-4 mAbs enabled us to delineate eosinophils as VLA-4high CD 16- cells from any other leukocyte populations in the whole blood. CD44 was found to be constitutively expressed on resting eosinophils, and expression increased upon cytokine-mediated activation. In all bronchial asthma patients examined, CD44high eosinophils were enriched in sputum relative to peripheral blood, indicating that eosinophils in sputum were more activated than those in blood. By comparing the extent of CD44 expression on blood eosinophils from poorly controlled and well-controlled asthma patients, we unexpectedly found that the density of CD44 expression is higher on blood eosinophils from the well-controlled group. Thus, the extent of CD44 expression on blood eosinophils is a novel marker indicative of the mangement of bronchial asthma. Deterioration of the asthma management with a concomitant decrease in CD44 expression on peripheral eosinophils implies that CD44 may play an important role in facilitating the transmigration of activated, CD44high eosinophils from the circulation to the respiratory tracts. PMID- 9363931 TI - Identification of surface molecules on eosinophils and lymphocytes in blood from patients with eosinophilia. AB - Surface molecules on eosinophils and lymphocytes in blood from patients with hypereosinophilic syndrome (HES), Kimura's disease and normal volunteers were examined. In all 3 patients with HES, CD54-positive eosinophils were increased and in some patients with HES and Kimura's disease HLA-DR-positive eosinophils were increased. Additionally, CD11b-positive, CD16-positive, CD25-positive, CD54 positive, CD69-positive and HLA-DR-positive lymphocytes were increased in some of these patients. PMID- 9363933 TI - Synergistic activation of eosinophil superoxide anion generation by VCAM-1 and GM CSF. Involvement of tyrosine kinase and protein kinase C. AB - During the development of allergic inflammation of asthma, eosinophils (EOS) are likely to interact with endothelial adhesion molecules, such as VCAM-1 and inflammatory cytokines, such as GM-CSF. To determine whether VCAM-1 and GM-CSF can interact to modify EOS superoxide anion (O2-) generation, peripheral blood EOS were incubated in either recombinant human (rh)-VCAM-1 or buffer (control) coated 96-well plates in the presence or absence of 100 pM GM-CSF. VCAM-1 and GM CSF acted synergistically to stimulate O2- generation which was significantly inhibited by either genistein, a tyrosine kinase inhibitor, or staurosporine, a protein kinase C inhibitor. These results indicate that interaction between VCAM 1 and GM-CSF can stimulate EOS function and its eventual contribution to the allergic inflammation process. Furthermore, our results demonstrate the involvement of tyrosine kinase and protein kinase C in this specific EOS activation. PMID- 9363932 TI - Activation of eosinophils with cytokines produced by lung mast cells. AB - Here we show that the supernatant from activated lung mast cells induced the release of eosinophil cationic protein (ECP) from eosinophils. Lung mast cells were purified using affinity magnetic selection with monoclonal antibody (mAb) YB5.B8 to achieve a final mast cell purity of 93-99%. Eosinophils were purified by immunomagnetic negative selection (>98.0% pure). The supernatant was obtained from lung mast cells activated for 24 h with 1 microg/ml anti-IgE and 50 ng/ml stem cell factor (SCF). Human eosinophils were incubated with various concentrations of the supernatants for 4 h and ECP released was measured by RIA. Using 4 different donors' supernatant from mast cells, each donor's supernatant caused a dose-dependent release of ECP from eosinophils. The dilutant of 1:2 (v/v) of the supernatant induced 657.5 +/- 55.6 ng/10(6) eosinophils of ECP which is statistically significant (p = 0.008, n = 4) compared with the culture medium alone. Anti-interleukin (IL-5 neutralizing mAb, 10 microg/ml, and anti-tumor necrosis factor-alpha (TNF alpha) neutralizing mAb, 10 microg/ml, significantly inhibited the supernatant-induced ECP release in 79.3 +/- 9.4 and 68.2 +/- 14.1% (mean +/- SEM, n = 6, p < 0.005), respectively. Anti-granulocyte/macrophage colony-stimulating factor (GM-CSF) neutralizing mAb, 50 microg/ml, caused 68.0 +/ 6.1% of inhibition (p = 0.002). The isotype negative control had no measurable inhibitory or stimulatory effect for the stimuli. We confirmed that mast cells produce IL-5, GM-CSF and TNF alpha in response to IgE-dependent stimulation by using RT-PCR, in situ hybridization, ELISA and immunocytochemistry. A million of lung mast cells generated 41.4 pg (7.0-273.6) (median with range) of TNF alpha, 252.6 pg (158.7-3,652) of GM-CSF and 735 pg (< 10-2,750) of IL-5 24 h after activation with SCF and anti-IgE. These findings indicate that the human mast cells may contribute to the chronicity of tissue inflammation. PMID- 9363934 TI - IL-5 as a strong secretagogue for human eosinophils. AB - The ability of IL-5 to induce eosinophil degranulation was investigated. Peripheral blood eosinophils from patients with mildly allergic individuals were isolated with CD16- selection method. Eosinophils were then incubated with interleukin-5 (IL-5) (0.1-100 ng/ml) for 1-48 h and EPX in the supernatants were measured with RIA. We found that IL-5 induced significant amount of eosinophil protein X in a concentration-dependent manner at 24 h. Eosinophil viability was about 90% either in the presence or absence of IL-5 at 24 h. Eosinophils stimulated with IL-5 adhered to the plate. Anti-CD18 mAb blocked adhesion and degranulation induced by IL-5. Dexamethasone and TGFbeta significantly inhibited degranulation in a concentration-dependent manner. These results suggest that IL 5 may be a strong secretagogue for eosinophils, that adhesion via beta2 integrin is a requisite for degranulation, and that the anti-inflammatory effect of corticosteroids and TGFbeta may be exerted at least in part, through the inhibition of eosinophil degranulation. PMID- 9363935 TI - Induction of apoptosis in human eosinophilic leukemic cell line (EOL-1). AB - Exposure of human eosinophilic leukemic EOL-1 cells to H2O2, ascorbic acid derivatives, actinomycin D, low-molecular-weight polyphenols, UV irradiation, or hyperthermia resulted in nuclear fragmentation, but failed to induce internucleosomal DNA cleavage. The findings suggest that internucleosomal DNA fragmentation is not a universal biochemical hallmark of apoptosis. Removal of Ca2+ ions from the culture medium significantly reduced the cytotoxic activity of sodium ascorbate, but not that of H2O2. H2O2 significantly elevated the intracellular Ca2+ concentration, with or without Ca2+ in the culture medium. This suggests that sodium ascorbate and H2O2 initiate cell death by different mechanisms. Induction of apoptosis in in vitro systems might be useful in studying the pathogenesis of allergy or asthma. PMID- 9363936 TI - Compartmentalization of eukaryotic gene expression: causes and effects. PMID- 9363937 TI - Innate immunity: the virtues of a nonclonal system of recognition. PMID- 9363938 TI - NF-kappaB activation: the I kappaB kinase revealed? PMID- 9363939 TI - The cell center at 100. PMID- 9363940 TI - Association of the origin recognition complex with heterochromatin and HP1 in higher eukaryotes. AB - The origin recognition complex (ORC) is required to initiate eukaryotic DNA replication and also engages in transcriptional silencing in S. cerevisiae. We observed a striking preferential but not exclusive association of Drosophila ORC2 with heterochromatin on interphase and mitotic chromosomes. HP1, a heterochromatin-localized protein required for position effect variegation (PEV), colocalized with DmORC2 at these sites. Consistent with this localization, intact DmORC and HP1 were found in physical complex. The association was shown biochemically to require the chromodomain and shadow domains of HP1. The amino terminus of DmORC1 contained a strong HP1-binding site, mirroring an interaction found independently in Xenopus by a yeast two-hybrid screen. Finally, heterozygous DmORC2 recessive lethal mutations resulted in a suppression of PEV. These results indicate that ORC may play a widespread role in packaging chromosomal domains through interactions with heterochromatin-organizing factors. PMID- 9363941 TI - DNA damage-induced phosphorylation of p53 alleviates inhibition by MDM2. AB - DNA-damaging agents signal to p53 through as yet unidentified posttranscriptional mechanisms. Here we show that phosphorylation of human p53 at serine 15 occurs after DNA damage and that this leads to reduced interaction of p53 with its negative regulator, the oncoprotein MDM2, in vivo and in vitro. Furthermore, using purified DNA-dependent protein kinase (DNA-PK), we demonstrate that phosphorylation of p53 at serines 15 and 37 impairs the ability of MDM2 to inhibit p53-dependent transactivation. We present evidence that these effects are most likely due to a conformational change induced upon phosphorylation of p53. Our studies provide a plausible mechanism by which the induction of p53 can be modulated by DNA-PK (or other protein kinases with similar specificity) in response to DNA damage. PMID- 9363942 TI - Crystal structure of the delta' subunit of the clamp-loader complex of E. coli DNA polymerase III. AB - The crystal structure of the delta' subunit of the clamp-loader complex of E. coli DNA polymerase III has been determined. Three consecutive domains in the structure are arranged in a C-shaped architecture. The N-terminal domain contains a nonfunctional nucleotide binding site. The catalytic component of the clamp loader complex is the gamma subunit, which is homologous to delta'. A sequence structure alignment suggests that nucleotides bind to gamma at an interdomain interface within the inner surface of the "C." The alignment is extended to other clamp-loader complexes and to the RuvB family of DNA helicases, and suggests that each of these is assembled from C-shaped components that can open and close the jaws of the "C" in response to ATP binding and hydrolysis. PMID- 9363943 TI - Recombinational DNA repair: the RecF and RecR proteins limit the extension of RecA filaments beyond single-strand DNA gaps. AB - In the presence of both the RecF and RecR proteins, RecA filament extension from a single strand gap into adjoining duplex DNA is attenuated. RecR protein alone has no effect, and RecF protein alone has a reduced activity. The RecFR complexes bind randomly, primarily to the duplex regions of the DNA, and the extension of the RecA filament is halted at the first complex encountered. A very slow lengthening of RecA filaments observed in the presence of RecFR is virtually eliminated when RecF is replaced with an RecF mutant protein that does not hydrolyze ATP. These observations are incorporated into an expanded model for the functions of RecF, RecO, and RecR proteins in the early stages of postreplication DNA repair. PMID- 9363944 TI - CENP-E is a plus end-directed kinetochore motor required for metaphase chromosome alignment. AB - Mitosis requires dynamic attachment of chromosomes to spindle microtubules. This interaction is mediated largely by kinetochores. During prometaphase, forces exerted at kinetochores, in combination with polar ejection forces, drive congression of chromosomes to the metaphase plate. A major question has been whether kinetochore-associated microtubule motors play an important role in congression. Using immunodepletion from and antibody addition to Xenopus egg extracts, we show that the kinetochore-associated kinesin-like motor protein CENP E is essential for positioning chromosomes at the metaphase plate. We further demonstrate that CENP-E powers movement toward microtubule plus ends in vitro. These findings support a model in which CENP-E functions in congression to tether kinetochores to dynamic microtubule plus ends. PMID- 9363945 TI - Cooking with calcium: the recipes for composing global signals from elementary events. AB - Recent studies have suggested that global intracellular Ca2+ signals arise from the summation and coordination of subcellular elementary release events (e.g., "Ca2+ puffs"), although the modes of recruitment of such signals are unknown. In order to understand how cells utilize elementary Ca2+ release events, we imaged Ca2+ transients evoked through the phosphoinositide pathway in HeLa cells using confocal microscopy. During the pacemaker phase leading to the global Ca2+ signal, elementary Ca2+ release events were recruited in (1) frequency, (2) amplitude, and (3) spatial domains. Since each digital elementary event contributes to a small change of the analog cytosolic Ca2+ concentration, the net effect of the advancement in the three domains is to drive the ambient Ca2+ concentration toward a threshold where the signal becomes regenerative, resulting in a global Ca2+ wave. PMID- 9363947 TI - Transcytosis and surface presentation of IL-8 by venular endothelial cells. AB - Chemokines have been convincingly implicated in actuating inflammatory leukocyte emigration. To affect the circulating leukocytes, tissue-derived chemokines have to traverse the endothelial cells (ECs). This was thought to be accomplished by chemokine diffusion through the intercellular gaps. On the contrary, we show by electron microscopy that the prototype chemokine IL-8 is internalized by venular ECs abluminally and transcytosed to the luminal surface. Here, it is presented to the adherent leukocytes on the EC membrane, predominantly in association with the EC projections. The intact C terminus of IL-8, the molecule's "immobilization" domain, is required for the EC binding, transcytosis, and consequently, the in vivo proemigratory activity of IL-8, indicating that the described subcellular interactions of IL-8 with the ECs are functionally relevant. PMID- 9363946 TI - Calmodulin regulation of Drosophila light-activated channels and receptor function mediates termination of the light response in vivo. AB - Calmodulin (CAM) participates in a variety of intracellular transduction processes by modulating signaling molecules in response to calcium changes. We report the characterization of Drosophila Cam mutants and the role of CAM in photoreceptor cell function. Contrary to current models of excitation and TRP channel function, we demonstrate that the transient phenotype of trp mutants can be explained by CAM regulation of the TRPL channel rather than by the loss of a store-operated conductance leading to depletion of the internal stores. We also analyzed light responses in a variety of mutant and transgenic backgrounds and demonstrate the importance of calmodulin in mediating calcium-dependent negative regulation of phototransduction. Our results show that CAM coordinates termination of the light response by modulating receptor and ion channel activity. PMID- 9363948 TI - Xsox17alpha and -beta mediate endoderm formation in Xenopus. AB - We have isolated two Xenopus relatives of murine Sox17 expressed in gastrula presumptive endoderm. Xsox17alpha and -beta expression can be induced in animal caps by activin, but not by FGF. Ectopic expression of these genes in animal caps induces the expression of endoderm markers; this induction is blocked by overexpression of a fusion of the Xsox17beta HMG domain to the Drosophila Engrailed repressor domain, as is induction of endoderm markers by activin and the expression of endodermal markers in whole embryos and isolated vegetal poles. These experiments, as well as the effects of the mRNAs on embryo phenotypes, suggest that the Xsox17 genes mediate an activin-induced endoderm differentiation pathway in animal caps and are involved in normal endoderm differentiation in embryos. PMID- 9363950 TI - Production of a DPP activity gradient in the early Drosophila embryo through the opposing actions of the SOG and TLD proteins. AB - During early Drosophila embryogenesis, several zygotic gene products act to establish a posttranscriptional activity gradient of the morphogen DPP. Among these molecules, Tolloid, a putative metalloprotease related to BMP-1, enhances DPP function, while SOG, an ortholog of the Xenopus organizer Chordin, inhibits DPP function. Using epistasis tests and a Xenopus secondary axis induction assay, we show that TLD negates the inhibitory effects of SOG/CHD on DPP/BMP-type ligands. In transient transfection assays, we demonstrate that TLD cleaves SOG and that cleavage is stimulated by DPP. We propose that formation of the embryonic DPP activity gradient involves the opposing effects of SOG inhibiting DPP and TLD processing SOG to release DPP from the inhibitory complex. PMID- 9363951 TI - A piece of my mind. Facing the future. PMID- 9363952 TI - Stem cells hold vision for the future. PMID- 9363949 TI - Cleavage of Chordin by Xolloid metalloprotease suggests a role for proteolytic processing in the regulation of Spemann organizer activity. AB - The Xolloid secreted metalloprotease, a tolloid-related protein, was found to cleave Chordin and Chordin/BMP-4 complexes at two specific sites in biochemical experiments Xolloid mRNA blocks secondary axes caused by chordin, but not by noggin, follistatin, or dominant-negative BMP receptor, mRNA injection. Xolloid treated Chordin protein was unable to antagonize BMP activity. Furthermore, Xolloid digestion released biologically active BMPs from Chordin/BMP inactive complexes. Injection of dominant-negative Xolloid mRNA indicated that the in vivo function of Xolloid is to limit the extent of Spemann's organizer field. We propose that Xolloid regulates organizer function by a novel proteolytic mechanism involving a double inhibition pathway required to pattern the dorsoventral axis: [formula in text]. PMID- 9363953 TI - Nobel Prize to Stanley Prusiner for prion discovery. PMID- 9363955 TI - 'Fresh produce initiative' for imports proposed. PMID- 9363954 TI - Novel therapies to prevent diabetic retinopathy. PMID- 9363956 TI - From the Centers for Disease Control and Prevention. Update: influenza activity- worldwide, March-August 1997. PMID- 9363957 TI - From the Centers for Disease Control and Prevention. Update: trends in AIDS incidence--United States, 1996. PMID- 9363958 TI - From the Centers for Disease Control and Prevention. Poisonings associated with illegal use of aldicarb as a rodenticide--New York City, 1994-1997. PMID- 9363959 TI - Cataract extraction rates and insurance status. PMID- 9363960 TI - Cataract extraction rates and insurance status. PMID- 9363961 TI - Cataract extraction rates and insurance status. PMID- 9363962 TI - Cataract extraction rates and insurance status. PMID- 9363963 TI - The National Council on Patient Information and Education. PMID- 9363964 TI - Physician-assisted suicide: the Dutch case. PMID- 9363965 TI - More on prenatal magnesium sulfate and risk of cerebral palsy. PMID- 9363966 TI - Physiatry and care of patients with neurofibromatosis. PMID- 9363967 TI - Moral medicine and universal health care. PMID- 9363968 TI - Postlicensure effectiveness of varicella vaccine during an outbreak in a child care center. AB - CONTEXT: Because lyophilized varicella vaccine must be stored frozen at -15 degrees C or less (> or = 5 degrees F) and administered within 30 minutes after reconstitution, the potential exists for decreased vaccine effectiveness when the vaccine is used under field conditions. OBJECTIVES: To describe an outbreak of varicella in a child care center and to determine postlicensure effectiveness of varicella vaccine. DESIGN: Retrospective cohort study. SETTING: A child care center in DeKalb County, Georgia, in 1996. PARTICIPANTS: Of the 184 children registered in the child care center, 148 were eligible for the study based on absence of history of varicella before January 1, 1996. MAIN OUTCOME MEASURES: Data on disease status, severity and impact of disease, and risk factors for varicella and for vaccine failure were obtained from parents and their children's pediatricians. Varicella vaccine effectiveness was calculated among children aged 12 months or older (eligible for vaccination) using the cohort method. RESULTS: The outbreak started on January 17, 1996, and lasted 15 weeks. Of the 148 eligible children, 81 (55%) developed varicella. Cases among children younger than 12 months (n =7) were more severe than cases among older children. Varicella occurred in 9 (14%) of 66 vaccinated children and 72 (88%) of 82 unvaccinated children. Varicella was less severe and resulted in fewer days of absence from the child care center among vaccinated compared with unvaccinated cases. Varicella vaccine effectiveness against all forms of disease was 86% (95% confidence interval [CI], 73%-92%), and against moderate-to-severe varicella disease it was 100% (95% CI, 96%-100%). Vaccinated children with asthma or other reactive airway diseases were 7.1 times more likely to have varicella than were vaccinated children without reactive airway diseases (95% CI, 2.4-21.3). CONCLUSIONS: Varicella vaccine administered under routine conditions in physicians' offices was highly effective in preventing varicella in an outbreak characterized by intense exposure. The role of asthma and other reactive airway diseases as risk factors for varicella disease and vaccine failure deserves to be investigated further. PMID- 9363969 TI - Early health effects of the emerging tobacco epidemic in China. A 16-year prospective study. AB - CONTEXT: In recent decades, there has been a rapid and substantial increase in tobacco consumption in China, particularly by men, but little is known from local epidemiologic studies about the pattern of smoking-related deaths. OBJECTIVE: To assess the current health effects of cigarette smoking in Shanghai, China. DESIGN: Prospective observational study of mortality in relation to cigarette smoking. SETTING: Eleven factories in urban Shanghai. SUBJECTS: A total of 9351 adults (6494 men and 2857 women) aged 35 to 64 years at baseline survey during the 1970s. OUTCOME MEASURES: All-cause and cause-specific mortality. RESULTS: During an average follow-up of 16 years, 881 men and 207 women died. Among men, 61% had described themselves as current cigarette smokers at baseline, and their overall mortality was significantly greater than that of nonsmokers (relative risk [RR], 1.4; 95% confidence interval [CI], 1.2-1.7; P<.001). The excess was almost twice as great (RR, 1.8; 95% CI, 1.5-2.2 [corrected]; P<.001) among the men who had begun smoking before the age of 25 years and was significantly associated with the number of cigarettes smoked (P<.001 for trend) after adjustment for other major risk factors. The chief sources of the excess were lung cancer (RR, 3.8; 95% CI, 2.1-6.8; P<.001), esophageal cancer (RR, 3.6; 95% CI, 1.2-10.5; P=.02), liver cancer (RR, 2.0; 95% CI, 1.1-3.7; P=.03), coronary heart disease (RR, 1.8; 95% CI, 1.0-3.2; P=.04), and chronic obstructive pulmonary disease (RR, 2.5; 95% CI, 1.4-4.4; P<.01). Among the men in this Chinese population, about 20% (95% CI, 12%-29%) of all deaths during the study period could be attributed to cigarette smoking. Of these deaths, one third involved lung cancer, one third involved other cancers, and one third involved other diseases. Only 7% of women described themselves as current cigarette smokers at baseline, but among them there was also a statistically significant excess of overall mortality (RR, 1.7; 95% CI, 1.2-2.5; P<.01). CONCLUSIONS: Cigarette smoking is already a major cause of death in China, and among middle aged Shanghai men, about 20% of all deaths during the 1980s were due to smoking. The excess was greatest among men who began smoking before the age of 25 years, about 47% of whom would, at 1987 mortality rates, die between the ages of 35 and 69 years (compared with only 29% of nonsmokers). These estimates reflect the consequences of past smoking patterns. The future health effects of current smoking patterns are likely to be greater because of the recent large increase in cigarette consumption, particularly at younger ages, in China. PMID- 9363970 TI - Mortality attributable to cigarette smoking in China. AB - CONTEXT: The few published prospective studies of smoking and mortality in China have reported low relative risks, but the durations of follow-up were short. OBJECTIVE: To assess the mortality of ever- and never-smokers in a cohort after 20 years of follow-up. DESIGN, SETTING, AND SUBJECTS: A cohort analytic study in a machinery factory in Xi'an, China, involving 1696 people aged 35 years or older (1124 men and 572 women) examined in May 1976. MAIN OUTCOME MEASURES: All-cause and tobacco-associated mortality. RESULTS: A total of 56% of the men and 12% of the women were ever-smokers at baseline. Through August 31, 1996, 218 persons (173 men and 45 women) had died. The relative risks (95% confidence intervals [CIs]) for ever smoking (after adjusting for age, marital status, occupation, education, diastolic blood pressure, and triglyceride and cholesterol levels) for deaths resulting from all causes, all cancer, and coronary heart disease were, respectively, 2.42 (95% CI, 1.72-3.42), 2.50 (95% CI, 1.41-4.43), and 3.61 (95% CI, 1.35-9.67) in men and 2.32 (95% CI, 1.18-4.56), 1.98 (95% CI, 0.50-7.92), and 4.67 (95% CI, 0.78-27.8) in women. CONCLUSIONS: Previous prospective studies of smoking-related mortality in China tended to underestimate the risks, probably because of short durations of follow-up. We have demonstrated that smoking is a major cause of death in China, and the risks are similar to those seen in the United States and the United Kingdom. Thus, about half of the 300 million smokers in China will eventually die of smoking-related diseases if urgent tobacco control measures are not instituted to prevent this growing epidemic. PMID- 9363971 TI - Long-term cholesterol-lowering effects of 4 fat-restricted diets in hypercholesterolemic and combined hyperlipidemic men. The Dietary Alternatives Study. AB - CONTEXT: The long-term effect of aggressively vs moderately fat-restricted diets has not been studied extensively in free-living subjects with different types of hyperlipidemia. OBJECTIVE: To compare the cholesterol-lowering effects of 4 levels of dietary fat intake restriction after 1 year. DESIGN: Randomized, parallel, comparison trial. SETTING: Male employees of a large industry. PARTICIPANTS: A total of 444 men had low-density lipoprotein cholesterol (LDL-C) levels above the 75th age-specific percentile. Subjects with triglyceride (TG) levels less than the 75th age-specific percentile were defined as hypercholesterolemic (HC) and those with TG levels at or above the 75th age specific percentile were defined as combined hyperlipidemic (CHL). INTERVENTIONS: Hypercholesterolemic subjects were randomized to diets 1, 2, 3, and 4 taught to contain 30%, 26%, 22%, and 18% fat, and the CHL subjects were randomized to diets 1, 2, and 3. All 4 diets were taught to subjects and spouses or partners in 8 weekly 2-hour classes. MAIN OUTCOME MEASURES: Plasma lipoprotein levels after 1 year. RESULTS: Fat intake after 1 year declined from a mean of 34% to 36% of energy to 27%, 26%, 25%, and 22% in the 4 HC diet groups and 28%, 26%, and 25% in the 3 CHL diet groups. Mean+/-SD percent LDL-C reductions were 5.3%+/-16.2%, 13.4%+/-12.6%, 8.4%+/-11.2%, and 13.0%+/-15.7% in the HC diet groups and 7.0%+/ 16.2%, 2.8%+/-15.8%, and 4.6%+/-13.5% in the CHL diet groups (P<.01 in all but 1 instance). Apoprotein B levels decreased 8.6%, 10.7%, 4.3%, and 5.3% in the HC groups and 14.6%, 11.4%, and 9.9% in the CHL groups (P<.05-.01 in each instance). Triglyceride levels increased significantly in subjects following HC diets 3 and 4, 21.7% and 38.7% (P<.05 and .01), but not in any CHL subjects. High-density lipoprotein cholesterol decreased 2.8% and 3.2% in subjects on HC diets 3 and 4, respectively (P<.05 in both cases). CONCLUSIONS: After 1 year, moderate restriction of dietary fat intake attains meaningful and sustained LDL-C reductions in HC subjects and apoprotein B reductions in both HC and CHL subjects. More extreme restriction of fat intake offers little further advantage in HC or CHL subjects and potentially undesirable effects in HC subjects. PMID- 9363972 TI - Early detection of prostate cancer. Serendipity strikes again. AB - An underappreciated characteristic of prostate cancer screening is that it may detect some prostate cancers solely by serendipity or chance. Serendipity, previously described in the detection of colonic neoplasms, could affect prostate cancer detection when a screening test result is abnormal for reasons other than the presence of prostate cancer, but prostate cancer is coincidentally detected during the subsequent evaluation of the abnormal screening result. We reviewed published articles about prostate cancer screening, searching for evidence of serendipity. We defined serendipity in digital rectal examination (DRE) screening as the discovery of a prostate cancer by the random biopsy of an area of the prostate gland other than the palpable suspicious area that prompted the biopsy. We defined serendipity in prostate-specific antigen (PSA) screening as the discovery of a prostate cancer by the random biopsy of a nonpalpable (stage T1c) prostate cancer less than 1.0 cm3 in volume, since tumors less than 1.0 cm3 are generally too small to cause elevated PSA levels. We found that serendipity may be responsible for the detection of more than one quarter of apparently DRE detected prostate cancers and up to one quarter of apparently PSA-detected cancers. Additionally, serendipity played a larger role in the detection of smaller tumors that are common but of uncertain clinical significance. We conclude that serendipity-detected prostate cancers contribute to an overestimation of the true information value of DRE and PSA screening. Whether serendipity is advantageous in prostate cancer screening depends on the as yet uncertain outcomes for men with smaller prostate cancers. However, given our estimates of the potential magnitude of the impact of serendipity, the currently popular DRE- and PSA-based screening strategy may not be optimal. If smaller prostate cancers are important, then we are not finding enough; if they are unimportant, then we are finding too many that we may feel compelled to treat aggressively. PMID- 9363973 TI - Reliability of a history of previous varicella infection in adults. AB - CONTEXT: Apparent second episodes of varicella are reported in immunocompetent hosts, but laboratory confirmation of prior immune status has rarely been possible. OBJECTIVE: To evaluate adult patients with varicella who claimed to have had previous varicella to determine whether they had true second episodes or primary cases with inaccurate clinical histories. DESIGN: Adult subjects with varicella who enrolled in an antiviral treatment trial were interviewed about a history of varicella. The clinical course of varicella was documented prospectively in all subjects. Serum samples that predated the acute illness were obtained from the US Navy's central serum storage facility for subjects who reported a previous episode of varicella. These stored samples were tested in parallel by enzyme-linked immunosorbent assay, latex agglutination, and Western blot for IgG antibodies to varicella-zoster virus (VZV). PARTICIPANTS: Twenty military personnel with varicella and a history of the disease. SETTING: A military hospital in San Diego, Calif. MAIN OUTCOME MEASURE: Presence or absence of antibodies to VZV. RESULTS: Twenty (10.8%) of 184 adults with serologically confirmed acute varicella reported a prior history of varicella. The clinical course of these 20 patients did not differ from those with no history of varicella. Serum samples that had been collected a mean of 12.4 months (median, 12 months; range, 3 days to 34 months) before the incident episode were available for 19 subjects. All 19 serum samples lacked IgG antibodies to VZV. CONCLUSION: A history of previous varicella infection in adults with varicella may not be reliable. True second episodes of varicella are probably rare in immunocompetent adults. PMID- 9363974 TI - Deciding life and death in the courtroom. From Quinlan to Cruzan, Glucksberg, and Vacco--a brief history and analysis of constitutional protection of the 'right to die'. AB - This article analyzes judicial determinations on the "right to die" from Quinlan to Cruzan, Glucksberg, and Vacco. The body of law known as right-to-die cases extends ordinary treatment refusal doctrine to end-of-life decisions. The courts, having affirmed a right to refuse life-sustaining treatment, held that certain categorical distinctions that had been drawn lacked a rational basis. No rational distinction could be made between competent vs incompetent patients, withholding vs withdrawing treatment, and ordinary vs extraordinary treatment. The courts, however, had persistently affirmed one categorical distinction: between withdrawing life-sustaining treament on the one hand and active euthanasia or physician-assisted dying on the other. In Washington v Glucksberg and Vacco v Quill, the Supreme Court unanimously held that physician-assisted suicide is not a fundamental liberty interest protected by the Constitution. Notably, five members of the Court wrote or joined in concurring opinions that took a more liberal view. The Court powerfully approved aggressive palliation of pain. The Supreme Court, hinting that it would find state legalization of physician assisted suicide constitutional, invited the nation to pursue an earnest debate on physician assistance in the dying process. PMID- 9363975 TI - Vaccination for varicella--just do it! PMID- 9363977 TI - How expensive is unlimited mental health care coverage under managed care? AB - OBJECTIVES: To study costs, access, and intensity of mental health care under managed care carve-out plans with generous coverage; compare with assumptions used in policy debates; and simulate the consequences of removing coverage limits for mental health care as required by the Mental Health Parity Act. DESIGN: Claims data from 1995 and 1996 for 24 managed care carve-out plans; all plans offered unlimited mental health coverage with minimal co-payments. OUTCOME MEASURES: Probability of care, intensity of care, and total costs broken down by service type and type of enrollee. RESULTS: Assumptions used in last year's policy debate overstate actual managed care costs by a factor of 4 to 8. In the plans studied, costs are lower owing to reduced hospitalization rates, a relative shift to outpatient care, and reduced payments per service. However, access to mental health specialty care increased (7.0% of enrollees) compared with the preceding fee-for-service plans (6.5%) or free care in the RAND Health Insurance Experiment (5.0%). Removing an annual limit of $25000 for mental health care, which is the average among plans currently imposing limits, will increase insurance payments only by about $1 per enrollee per year. Children are the main beneficiaries of expanded benefits. CONCLUSIONS: Concerns about costs have stifled many health system reform proposals. However, policy decisions were often based on incorrect assumptions and outdated data that led to dramatic overestimates. For mental health care, the cost consequences of improved coverage under managed care, which by now accounts for most private insurance, are relatively minor. PMID- 9363976 TI - Beyond the clouds--tobacco smoking in China. PMID- 9363978 TI - Modification of cardiac actions of RO 05-4864 by PK 11195 and flumazenil in the perfused rat heart. AB - The benzodiazepine analogue Ro 05-4864 [chlorodiazepam] (2.10[-5] to 4.10[-4] M) induced a concentration-dependent increase of coronary flow rate (Emax 82.4% [+/- 2.2 SEM]) and an increase of contraction force (Emax 68.3% [+/- 4.7 SEM]) of the retrograde perfused, isolated Langendorff rat heart. The influence of PK 11195, antagonist of the peripheral type benzodiazepine receptor, and flumazenil (Anexate), antagonist of the central type benzodiazepine receptor, on these responses to Ro 5-4864 was studied. In concentrations of 10(-7) to 5.10(-5) M, PK 11195 significantly reduced both the increase of coronary flow rate and of contraction force, without affecting these functions by itself; the positive inotropic response produced by Ro 05-4864 was even abolished in the presence of 5.10(-5) M PK 11195. The Emax values of Ro 05-4864 on both coronary flow and inotropy were reduced significantly by PK 11195. In the presence of flumazenil, 10(-7) to 10(-5) M, both the vasodilatory and the positive inotropic response induced by Ro 05-4864 were significantly counteracted as well. The Emax values of Ro 05-4864 were reduced significantly. In conclusion, the results support earlier suggestions that it is tempting to involve peripheral type benzodiazepine receptors in cardiac actions of benzodiazepines. The finding that the centrally acting benzodiazepine antagonist flumazenil reduced the cardiac actions of Ro 05 4864 is as yet difficult to explain. On the other hand concentrations of both agonist and antagonist employed are so-much high that interference of other receptors than benzodiazepine receptors must be considered as well. PMID- 9363979 TI - Expression of luteinizing hormone-releasing hormone and its receptor in porcine immune tissues. AB - Luteinizing hormone-releasing hormone (LHRH) is the primary regulator of pituitary LH release. However, LHRH has also been identified in extrahypothalamic sites including immune tissues. Accordingly, immunomodulatory properties for LHRH have been suggested. We wanted to determine whether LHRH and its receptor are produced by immune tissues in the pig. First, a cDNA was cloned and sequenced from the porcine hypothalamus that showed 87.5% homology with the human LHRH gene. Internal primers were identified from this sequence for amplifying a 268 bp product by PCR. In addition to the hypothalamus, PCR products reflecting LHRH mRNA were amplified in porcine spleen, thymus, and peripheral blood lymphocyte (PBL) cDNA. LHRH mRNA was not detected in liver, cerebral cortex, or pituitary tissue samples. Primers were designed to amplify a 360 bp fragment of LHRH receptor cDNA. PCR products reflecting LHRH-receptor mRNA were amplified in pig hypothalamus, pituitary, thymus, spleen and PBL cDNA samples. No such products were amplified in cortex and liver samples. In summary, we report the sequence of a cDNA coding for LHRH and Gonadotropin-RH associated peptide (GAP) in the pig hypothalamus. Additionally, we provide evidence that LHRH and its receptor are synthesized in porcine immune tissues. This leads us to speculate that LHRH may have local, immunomodulatory functions in pigs. PMID- 9363980 TI - Hematological changes in rats exposed to weak electromagnetic fields. AB - A number of experimental studies report that biological systems can be affected by in vivo exposure to low frequency and extremely low frequency electromagnetic fields. However, attempts to independently replicate some of these studies have shown the reported effects to be elusive. The difficulty in replicating results could be due to unidentified physical and/or biological parameters which may affect the response of a sample to electromagnetic fields. The present paper reports a failure to independently replicate a study showing that in vivo exposure to a pulsed magnetic field of 1.5 mT caused significant changes on plasma proteins in rats. Although the possibility has to be considered that the results from the seminal work were artifactual, substantial differences in levels of plasma proteins were observed between the control groups of the two studies indicating that the animals in the first study had an infectious illness. This observation supports the hypothesis that the state of physiological equilibrium of a biological system is crucial to its response to a potentially effective electromagnetic field. PMID- 9363981 TI - (Stearyl, Norleucine17)VIP hybrid antagonizes VIP receptors on non-small cell lung cancer cells. AB - The effects of VIP receptor antagonists were investigated using non-small cell lung cancer (NSCLC) cells. By Northern blot and RT-PCR, VIP1 receptors were detected on NSCLC cell line NCI-H1299. VIPhybrid,(N-Stearyl-Norleucine17) VIPhybrid ((SN) VIPhybrid) and PTC4495 inhibited 125I-VIP binding to NCI-H1299 cells with IC50 values of 500, 30 and 5000 nM respectively. (SN) VIPhybrid (1 microM) had no effect on basal cAMP but strongly inhibited the increase in cAMP caused by 10 nM VIP. The order of peptide potency to inhibit cAMP was (SN) VIPhybrid > VIPhybrid > PTC4495. (SN) VIPhybrid was more potent than VIPhybrid at inhibiting NCI-H1299 colony formation. Also, (SN) VIPhybrid was more potent than VIPhybrid at inhibiting NCI-H1299 xenograft formation in nude mice. These data suggest that (SN) VIPhybrid antagonizes VIP1 receptors on NSCLC cells. PMID- 9363982 TI - Substitution of 15(S)hydroxyeicosatetraenoic acid in phosphatidylinositol alters the growth of liver epithelial cells. AB - We investigated the substitution of 15(S)-hydroxyeicosatetraenoic acid (15(S)HETE) in phospholipid signaling pathways and its consequences on the growth of non-transformed (NT-) and spontaneously transformed (T-) rat liver epithelia cells (RLEC). 15(S)HETE was selectively incorporated into the sn-2 position of phosphatidylinositol (PI) and at a higher rate into T-RLEC. RLEC rapidly mobilized the resulting 15(S)HETE-containing PI (15(S)HETE-PI) and produced 1 acyl,2-[1(S)HETE]-glycerol. Although total diacylglycerol levels were similar in both cell types, the ratio 1-acyl,2-[15(S)HETE]-glycerol / 15(S)HETE-PI was higher in NT-RLEC, suggesting a lower mobilization of 15(S)HETE-PI in T-RLEC. Using rat brain protein kinase C, 1-stearoyl,2-[15(S)HETE]-glycerol was as potent an in vitro protein kinase C activator as 1-stearoyl,2-arachidonoyl-glycerol. Finally, selective substitution of 15(S)HETE in PI altered DNA synthesis in T RLEC: whereas low concentrations of 15(S)HETE (1 nM and 10 nM) in these cells were mitogenic, higher concentrations resulted in a 30% inhibition of DNA synthesis. PMID- 9363983 TI - Extracellular adenosine 5'-triphosphate induces Ca2+ efflux from freshly isolated adult rat cardiomyocytes: possible involvement of Na+/Ca2+ exchange mechanism. AB - In the present study, we examined the effect of extracellular adenosine 5' triphosphate (ATP) on Ca2+ efflux from freshly isolated adult rat cardiomyocytes. ATP at 1 mM caused a release of 3.6+/-0.08% of the total cellular content. The 45Ca2+ efflux from the cells was also stimulated by adenosine-5'-O-(3 thiotriphosphate) (ATP-gamma s), alpha, beta-methylene-ATP and adenosine 5' diphosphate (ADP), but not by adenosine 5'-monophosphate (AMP) or adenosine. The effect of ATP was inhibited by a known purinergic P2-receptor antagonist, but not by a P1-receptor antagonist. From these results, it is conceivable that the effect of ATP on Ca2+ efflux from cardiomyocytes is mediated through P2 purinoceptors. It was also observed that ATP caused a rise in [Ca2+]i to almost 200 nM. The ATP-stimulated 45Ca2+ efflux was not affected by removal of extracellular Ca2+, but was dependent on the presence of extracellular Na+. Moreover, ATP caused a 22Na+ influx into the cells of about 2.0-fold over the basal value. These result suggest that ATP stimulates extracellular Na+-dependent 45Ca2+ efflux from freshly isolated adult rat cardiomyocytes, probably through its stimulatory effect on plasma membrane P2-purinoceptors which may couple to Na+/Ca2+ exchange. PMID- 9363984 TI - Nutritional supplementation of nucleotides restores opioid CNS-mediated phenomena in mice. AB - Previous experiments have demonstrated that suppression of immune function by either cyclosporin A or by a nucleotide free (NF) diet results in attenuation of morphine withdrawal symptoms in mice suggesting that immune status impacts CNS opioid-related phenomena. The present study elaborates on these initial findings by examining the effects of repletion of the NF diet with nucleotides or their precursors on opiate withdrawal. Female Balb/c mice were divided into six groups: a control group (C) given a standard lab chow diet and five experimental groups each given one of the following diets: a nucleotide free diet (NF); the NF supplemented with 0.25% RNA (NFR 0.25); the NF supplemented with 2.5% RNA (NFR 2.5) the NF supplemented with 0.06% uracil (NFU 0.06); the NF supplemented with 0.6% uracil (NFU 0.6). The mice were made morphine dependent by subcutaneous implantation of morphine pellets. Seventy-two hours after morphine pellet implantation, withdrawal was precipitated with naloxone (2 mg/kg). The mice were then observed and two indicators of withdrawal scored: jumping and diarrhea. The NF, NFR 0.25, NFR 2.5 and NFU 0.06 groups demonstrated significantly attenuation of the withdrawal signs relative to control animals. The NFU 0.6 group, however, had withdrawal scores restored to near control levels for both jumping and diarrhea. This suggests that nucleotides, particularly uracil, may play an important role in the immune-to-brain signaling pathway. PMID- 9363985 TI - The ATP-depleting reagent iodoacetamide induces the degradation of protein kinase C alpha (PKC alpha) in LLC-PK1 pig kidney cells. AB - The alkylating reagent iodoacetamide, a potent inhibitor of sulfhydryl proteases, was found to stimulate the selective degradation of protein kinase C alpha (PKC alpha) isoform (80 KDa). Treatment of LLC-PK1 cells with iodoacetamide (0.5-15 mM) for 30-90 minutes at room temperature allowed by western blotting on total cell homogenate, revealed the appearance of an 50 KDa band that was still recognized with the antibody. However, iodoacetamide (15 mM) resulted in the total disappearance of the 80 KDa protein. Serine protease inhibitors, metalloprotease inhibitors and leupeptin failed to prevent the degradation of PKC alpha. The degradation persisted at 4 degrees C and in the absence of Ca2+. Iodoacetamide had no direct effect on purified PKC alpha. PKC activities in iodoacetamide-treated cells were also inhibited. In conclusion, the degradation of PKC alpha is a novel phenomenon. The degradation process could not be prevented by known protease inhibitors or in the absence of Ca2+ or by incubation at 4 degrees C and appears to involve interactions with unknown cellular intermediates. PMID- 9363986 TI - Effects of acute metabolic stress on plasma progesterone and testosterone in male subjects: relationship to pituitary-adrenocortical axis activation. AB - Stress effects on progesterone and testosterone as well as the relationship of these effects to the hypothalamic-pituitary-adrenal (HPA) axis activation have been extensively investigated in laboratory animals. There is less information about the impact of stress on sex steroids in humans. The purpose of the present study was to examine the influence of acute arterial levels of progesterone, testosterone, adrenocorticotropic hormone (ACTH), cortisol, gonadotropins and sex hormone binding globulin (SHBG) in healthy male subjects. The stressor used was glucoprivation induced by pharmacological doses of 2-deoxy-D-glucose (2DG) (40mg/kg). This stress resulted in increases in progesterone, decreases in testosterone and no significant change in gonadotropins or SHBG. ACTH and cortisol were robustly elevated and these elevations related significantly to changes in progesterone but not testosterone. The implications of these data for the understanding of the role of sex steroids in the stress response is discussed. PMID- 9363987 TI - Functional evidence linking potassium channels and afferent nerve-mediated mucosal protection in rat stomach. AB - Adenosine triphosphate-dependent potassium (K+ATP) channels in several types of vascular smooth muscles mediate the vasodilation induced by calcitonin gene related peptide (CGRP). Upon stimulation, primary afferent nerve terminals in the gastric mucosa release CGRP which mediates a protective hyperemia. We tested the hypothesis that a potassium channel blocker aggravates gastric mucosal injury by impairing afferent nerve-mediated hyperemia in the gastric mucosa. Rats were treated with K+ATP channel blocker, glybenclamide (20 mg/kg intravenously). Intragastric added ethanol (0.15 N HCl, 15% ethanol) and intragastric capsaicin (160 microM) were also administered. Glybenclamide aggravated the acidified ethanol-induced mucosal injury, and attenuated the mucosal hyperemia (hydrogen gas clearance) induced by intragastric acidified ethanol and intragastric capsaicin. These findings suggest for the first time that K+ATP channels modulate primary afferent nerve-mediated mucosal defense mechanisms in the gastric mucosa. PMID- 9363988 TI - Corticosterone levels during extinction of runway response in rats. AB - This investigation examined whether the hypothalamic-pituitary-adrenocortical axis would activate during extinction of a straight runway response. Four groups of rats were trained to run in a straight runway for 3 (for 3S and 3L groups) or 10 (for 10S and 10L groups) food pellets as a reward for either 15 (for 3S and 10S groups) or 25 (for 3L and 10L groups) acquisition days followed by 3 extinction days. Blood samples for determination of serum corticosterone concentration were taken from all animals under 5 different situations: 10 min after entering the experimental room, after the 24th acquisition day, after the first and third extinction days and under the deprivation control. Running speed of 10S and 10L groups in extinction days were reduced more quickly than that of 3S and 3L groups. After the third extinction day, serum corticosterone concentrations were significantly elevated in 10S and 10L, but not in 3S and 3L groups. These results indicate that the amount of reward in the acquisition phase influences not only the running speed, but also the corticosterone concentration in the extinction phase. PMID- 9363989 TI - Hemodynamic effects of the intravenous administration of cyclovirobuxine D [correction of cyclorirobuxine D] in anesthetized pigs. AB - The present study was undertaken in anesthetized pigs to determine the primary effects of cyclovirobuxine D [corrected] given intravenously on hemodynamic variables. In eight pigs, the administration of 1.5 mg/kg of cyclovirobuxine D [corrected] caused a small increase in aortic blood pressure. When this response was prevented, a decrease in heart rate was obtained in each of the eight pigs. When this response was also prevented, an increase in the maximum rate of change of left ventricular systolic pressure (left ventricular dP/dtmax) was observed. In four pigs, the decrease in heart rate and the increase in left ventricular dP/dtmax were progressively augmented by graded increases in the dose of cyclovirobuxine D [corrected]. In six pigs, the responses of hemodynamic variables to cyclovirobuxine D [corrected] were not affected by blockade of cholinergic and adrenergic receptors. In a further six pigs, blockade of nitric oxide synthase with N omega-nitro-L-arginine methyl ester did not affect the decrease in heart rate caused by the drug, but abolished the increases in left ventricular dP/dtmax and aortic blood pressure. The present study showed that intravenous administration of cyclovirobuxine D [corrected] primarily caused a decrease in heart rate and an increase in left ventricular inotropic state, which secondarily determined an increase in aortic blood pressure, and suggested that the response of heart rate involved a direct effect of the drug on the heart, while the response of left ventricular contractility was related to mechanisms dependent on the release of nitric oxide. PMID- 9363990 TI - Endotoxin induced increases in rat plasma pituitary-adrenocortical hormones are better reflected by alterations in tumor necrosis factor alpha than interleukin 1beta. AB - In order to assess the relative cytokine contribution to endotoxin stimulation of pituitary-adrenocortical hormone secretion, we measured plasma levels of interleukin-1beta (IL-1beta), tumor necrosis factor (TNF alpha), adrenocorticotropin (ACTH) and corticosterone following lipopolysaccharide (LPS) challenge in rats. LPS administration induced robust increases in both plasma ACTH and corticosterone levels at 3 h after i.p. injection; while ACTH decreased towards control levels, corticosterone remained at peak concentrations at 6 h after LPS injection. Basal levels of plasma IL-1beta were below the sensitivity of the ELISA and basal levels of plasma TNF alpha were 0.25+/-0.12 pM. Small but highly variable non-significant increases in plasma IL-1beta levels were seen at 3 h and 6 h after injection of LPS. The lack of functional consequences of the small increases in IL-1beta levels was demonstrated by unchanged levels of [125I]IL-1alpha binding in liver at 3 h after LPS injection. In contrast, dramatic increases in plasma TNF alpha concentrations were observed at 3 h and decreased to non-injected control levels at 6 h after LPS injection. There was a significant positive correlation between ACTH and TNF alpha after LPS injection, while no correlation was seen between ACTH and IL-1beta. These data demonstrate differential regulation of IL-1beta and TNF alpha by endotoxin treatment and suggest that TNF alpha may be a more potent mediator of LPS-induced ACTH secretion in rat. PMID- 9363991 TI - Suppression of intestinal polyp development by low-fat and high-fiber diet in Apc(delta716) knockout mice. AB - Most epidemiological and animal studies show a positive correlation of the dietary intake of fat with the incidence of colon cancer, whereas an inverse correlation of the dietary intake of fiber. In rats fed a diet low in fat and high in wheat bran fiber and calcium, a significant decrease was reported in the number of azoxymethane-induced aberrant crypt foci compared with those fed a high fat, low-fiber and low-calcium diet. Mutations in the human APC gene play a key role, not only in familial adenomatous polyposis, but also in many sporadic cancers of the entire digestive tract. We previously constructed a mouse strain Apc(delta716), carrying a truncation mutation at codon 716 of the Apc gene, the homolog of human APC (10). The heterozygous mice developed numerous intestinal polyps, and all microadenomas dissected from the earliest polyps had already lost the wild-type allele, indicating the loss of heterozygosity. Using these Apc(delta716) knockout mice, we have investigated the effect of a low-fat and high-fiber diet (LRD for 'low-risk' diet) on intestinal polyposis, and compared it with that of a high-fat and low-fiber diet (HRD for 'high-risk' diet). The mice were fed either diet for 7 weeks, and the number and size of intestinal polyps were scored. The LRD-fed mice had fewer polyps than the HRD-fed mice, by 36% in the small intestine and by 64% in the colon. As for the polyp size distribution, there was no significant difference between the HRD- and LRD-fed mice. These results indicate that LRD can suppress intestinal polyposis compared with HRD which does not, and suggest that its suppression is at the initiation of polyp formation. This is likely to be due to a decreased frequency of loss of heterozygosity, rather than a retarded growth of the polyp adenomas. PMID- 9363992 TI - Transforming growth factor beta type I receptor acts as a potent tumor suppressor in rat bladder carcinoma. AB - Transforming growth factor beta1 (TGFbeta1) is a potent growth inhibitor for most cells, including neoplastic cells. However, there are several types of malignant cells that are resistant to its growth-inhibitory effect. LMC19, a highly malignant rat urothelial cell line, lacks TGFbeta1 receptor (TbetaRI) and is insensitive to the growth-suppresive effect of TGFbeta1. We transfected an expression vector containing human TbetaRI into this cell line. In control cells transfected with the neo gene alone, no inhibitory effect on growth was observed in vitro by the addition of anti-TGFbeta1 antibody or recombinant TGFbeta1 into serum-free medium. In contrast, the growth of all transfectants tested was inhibited significantly under serum-free conditions because of their endogenous TGFbeta synthesis. The growth was reduced further by the addition of recombinant TGFbeta1. This response pattern is consistent with TGFbeta1 mediating its effects by an autocrine and paracrine mechanism. The tumorigenicity of the cells was tested in a heterotopically transplanted urinary bladder system, which was generated as an orthotopic test site in athymic nude mice. All nine mice tested receiving control cells formed deeply invasive, undifferentiated-cell carcinomas and multiple metastatic foci in the lungs. In contrast, none of the mice receiving transfectants of TbetaRI formed bladder tumors or metastases. Taken together, these observations indicate that TbetaRI exhibits a potent tumor suppressor effect in bladder carcinoma. PMID- 9363993 TI - Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon. AB - We have examined whether dietary polyamines influence the formation and initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in rat colon. Effects of a combination of dietary polyamines at three dose levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g; spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied in animals in two different experimental situations: animals treated with AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a specific inhibitor of endogenous polyamine synthesis. In both experimental situations, dietary polyamines enhanced the growth of ACF, expressed as the number of large ACF (foci with three or more aberrant crypts, ACF > or = 3), whereas the formation of ACF, expressed as the number of ACF, was apparently not altered. In animals treated with AOM alone, maximal growth enhancing effect on ACF was nearly obtained with the median level of dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of DFMO was counteracted by dietary polyamines in a dose-dependent manner, and it was abolished at the highest level of polyamines. In conclusion, it was demonstrated that dietary polyamines are able to enhance the growth of AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused inhibition of ACF growth, probably by compensating for the DFMO-reduced endogenous polyamine synthesis. PMID- 9363994 TI - Genetic instability and p53 mutations in metastatic foci of mouse urinary bladder carcinomas induced by N-butyl-N-(4-hydroxybutyl)nitrosamine. AB - In a variety of human malignancies, alteration of the p53 tumour suppressor gene is known as a significant indicator of late progression events including invasion and metastasis, with a possible close relationship to genetic instability. Mutational analysis of the p53 and H-ras genes was performed for 10 pairs of N butyl-N-(4-hydroxybutyl)nitrosamine-induced invasive mouse urinary bladder carcinomas and metastatic foci. p53 Mutations were found in nine of 10 (90%) primary carcinomas and seven of 10 (70%) metastatic foci. A total of eight p53 mutations in primary carcinomas were common in metastatic foci in six pairs. Additional p53 or H-ras mutations which were not identified in the primary carcinomas were found in three metastatic foci. Evaluation of the allelic distribution of the p53 mutations using RT-PCR, PCR and subcloning, further indicated possible intra-tumour genomic heterogeneity or excess copy numbers of the p53 gene due to genetic instability. Overall, p53 alterations were frequent in mouse urinary bladder carcinomas demonstrating progression. The results suggest that genetic instability might underlie generation of additional genetic alterations in this animal model. PMID- 9363995 TI - Bacterial and mammalian DNA alkyltransferases sensitize Escherichia coli to the lethal and mutagenic effects of dibromoalkanes. AB - Here we confirm and extend our previous studies demonstrating that the mutagenic potency of 1,2-dibromoethane (DBE) and dibromomethane (DBM) is markedly enhanced (not prevented) in bacteria expressing the O6-alkylguanine-DNA alkyltransferase (ATase) encoded by the Escherichia coli ogt gene. We demonstrate that, in close parallel with mutagenesis, the Ogt ATase sensitizes the bacteria to the lethal effects of these carcinogens, suggesting that one or more of the potentially mutagenic lesions induced by DBE and DBM in the presence of Ogt has additional lethal capacity. We further demonstrate that the sensitization to both lethality and mutagenesis by DBE and DBM is a property shared by other DNA alkyltransferases. This objective was accomplished by quantifying the induction of mutations and lethal events in ogt- ada- E. coli expressing an exogenous bacterial or mammalian ATase from a multicopy plasmid. Mammalian recombinant ATases enhanced the lethal and mutagenic actions of DBE and suppressed the lack of sensitivity of the vector-transformed bacteria to DBM. In most cases the order of effectiveness of the ATases ranked: murine > human > Ogt > rat. Further comparisons included the full-length Ada ATase from E. coli and a truncated Ada version (T-ada) that retains the O6-methylguanine binding domain of the protein. The full-length Ada ATase was effective in enhancing the lethality but not the mutagenicity induced by DBE and DBM. The T-ada ATase provided less sensitization than Ada to lethality by DBE, but of the three bacterial ATases T-ada yielded the highest sensitization to mutagenesis by this compound. T-ada and Ada ATases were in general less effective than the mammalian versions, with the exception of the rat recombinant ATase. The effectiveness of the different mammalian and bacterial ATases in promoting the deleterious actions of dibromoalkanes was compared with the effectiveness of these proteins in suppressing the lethal and mutagenic effects induced by N-nitroso-N-methylurea. The ability to sensitize E. coli to the lethal and mutagenic effects of DBE and DBM seems restricted to DNA alkyltransferase, since overexpression of thioredoxin (Trx) or glutaredoxin (Grx1) in ogt- ada- cells showed no effect, in spite of the reported potential of bioactive dihaloethane-derived species to alkylate Trx. PMID- 9363996 TI - O6-methylguanine-DNA methyltransferase activity in human buccal mucosal tissue and cell cultures. Complex mixtures related to habitual use of tobacco and betel quid inhibit the activity in vitro. AB - Extracts prepared from tissue specimens of normal, non-tumourous human buccal mucosa, and cultured buccal epithelial cells and fibroblasts, exhibited O6 methylguanine-DNA methyltransferase (MGMT) activity by catalysing the repair of the premutagenic O6-methylguanine lesion in isolated DNA with rates of 0.2 to 0.3 pmol/mg protein. An SV40 T antigen-immortalized buccal epithelial cell line termed SVpgC2a and a buccal squamous carcinoma line termed SqCC/Y1, both of which lack normal tumour suppressor gene p53 function, exhibited about 50 and 10% of the MGMT activity of normal cells, respectively. The normal, experimentally transformed and tumourous buccal cell types showed MGMT mRNA levels which correlated with their respective levels of MGMT activity. Exposure of buccal cell cultures to various organic or water-based extracts of products related to the use of tobacco and betel quid, decreased both cell survival (measured by reduction of tetrazolium dye) and MGMT activity (measured subsequently to the exposures in cellular extracts). Organic extracts of bidi smoke condensate and betel leaf showed higher potency than those of tobacco and snuff. An aqueous snuff extract also decreased both parameters, whereas an aqueous areca nut extract was without effect. The well-established sulph-hydryl-reactive agent Hg2+, a corrosion product of dental amalgam, served as a positive control and decreased MGMT activity following treatment of cells within a range of 1-10 microM. Taken together, significant MGMT activities were demonstrated in buccal tissue specimens and in the major buccal mucosal cell types in vitro. Lower than normal MGMT activity in two transformed buccal epithelial cell lines correlated with decreased MGMT mRNA and lack of functional p53. Finally, in vitro experiments suggested the potential inhibition of buccal mucosal MGMT activity by complex mixtures present in the saliva of tobacco and betel nut chewers. PMID- 9363997 TI - Evidence that changes in Se-glutathione peroxidase levels affect the sensitivity of human tumour cell lines to n-3 fatty acids. AB - The human lung adenocarcinoma cell line A-427 is significantly more sensitive to cytotoxic lipid peroxidation products of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) than the human lung adenocarcinoma cell line SK-LU-1, and the glioblastoma cell lines A-172 and U-87 MG. The cytotoxic effect as well as lipid peroxidation were abolished by vitamin E. The differential sensitivities of the cell lines were not correlated to the levels of lipid peroxidation products (measured as the end product malondialdehyde), indicating differences in sensitivities to products of lipid peroxidation. The high sensitivity of A-427 is apparently due to a low level of selenium-dependent glutathione peroxidase (GSH Px), because pretreatment with sodium selenite (250 nM) increased the GSH-Px activity 3- to 4-fold and protected the cells almost completely against the growth inhibitory effect of DHA. Furthermore, 2-phenyl-1,2-benzisoselenazol-3(2H) one (ebselen) a seleno-organic GSH-Px mimic, suppressed the cytotoxic action of DHA to A-427 in a dose dependent manner. Northern analysis demonstrated that pretreatment with sodium selenite (250 nM) was accompanied by an increased level of GSH-Px mRNA (1.8-fold) in A-427 cells, while the level remained unchanged under the same conditions in DHA/EPA-resistant A-172 cells. In addition, the level of selenophosphate synthetase mRNA (SelD), a key intermediate in tRNA(Sec) formation, increased 1.2- to 1.7-fold in A-427 and A-172 cells after pretreatment with sodium selenite. These results indicate that upregulation of GSH-Px activity by sodium selenite in the EPA/DHA sensitive cell line A-427 may be due to an increase in mRNAs for GSH-Px and a precursor important for formation of tRNA(Sec) which is required for incorporation of selenocysteine in GSH-Px during translation. These results demonstrate an important role for GSH-Px in the cellular defence against cytotoxic lipid peroxidation products. Furthermore, measurement of GSH-Px activities in tumour cells may be one useful biochemical predictor for their sensitivities to polyunsaturated fatty acids. PMID- 9363998 TI - A fish oil derived concentrate enriched in eicosapentaenoic and docosahexaenoic acid as ethyl ester suppresses the formation and growth of intestinal polyps in the Min mouse. AB - We examined whether the n-3 polyunsaturated fatty acid ethyl ester enriched fish oil K85 (54.4% of eicosapentaenoic acid and 30.3% of docosahexaenoic acid as ethyl esters) could inhibit the intestinal tumorigenesis in Min mice, a murine model of familial adenomatous polyposis (FAP). Min mice that are heterozygous for a nonsense mutation in the Apc gene, develop spontaneously multiple intestinal neoplasms, primarily in the small intestine. K85 was dissolved in corn oil (vehicle) and mixed into the AIN-76A diet. The total oil content (K85 + corn oil) was 12% in all diets. The various experimental diets contained 0 (vehicle control), 0.4, 1.25 or 2.5% of K85. In the small intestine, the mean number of tumors/mouse was 105 +/- 18 (SEM) in control males and 70 +/- 11 in control females. Dietary K85 treatment reduced the number of small intestinal tumors: in males, the maximum reduction was 66% (P = 0.002) with 0.4% of K85; and in females, the maximum reduction was 48% (P = 0.043) with 2.5% of K85, but the inhibition was only slightly increased from 0.4% to 2.5% of K85. The mean tumor diameter was 1.33 +/- 0.08 mm in control males and 1.06 +/- 0.08 in control females, and the diameter ranged from <0.1 mm (monocryptal adenomas) to 4 mm. The small intestinal tumor diameter was reduced by K85 in a dose-dependent manner: in males, with a maximum reduction of 26% (r = -0.64, P = 0.004); and in females, with a maximum reduction of 38% (r = -0.61, P < 0.004). In the large intestine, the mean number of tumors/mouse was 1.0 +/- 0.5 in males and 0.8 +/- 0.2 in females. Although K85 treatment tended to reduce the number and diameter of the large intestinal tumors, these effects did not reach statistical significance. Aberrant crypt foci not elevated from the flat mucosa (ACF(Min)) occurring in the colon of Min mice were also scored. The mean number of ACF(Min)/colon (3.8 +/- 0.9) and the crypt multiplicity (1.49 +/- 0.28) in females were reduced by 73% (P = 0.03) and 60% (P = 0.048) with 2.5% of K85, respectively, whereas no significant effect could be observed in the males. PMID- 9363999 TI - Inhibition of phorbol ester tumor promoter 12-O-tetradecanoylphorbol-13-acetate caused inflammatory responses in SENCAR mouse skin by black tea polyphenols. AB - Over the past 10 years many studies from several laboratories defined anticarcinogenic and anti-inflammatory effects of tea, a widely consumed beverage by the human population. Much of such work has been conducted with green tea or its polyphenolic constituents. Regarding black tea, studies have shown that its water extract affords protection against tumor promotion caused by chemical carcinogens or ultraviolet B radiation in murine skin carcinogenesis models. Several studies have shown that topical application of chemical tumor promoters to murine skin results in the induction of epidermal edema, hyperplasia and ornithine decarboxylase (ODC) and cyclo-oxygenase activities, and interleukin-1 alpha (IL-1alpha) and ODC mRNA expression. In this study, we assessed whether topical application of polyphenols isolated from black tea leaves (hereafter referred to as BTP) mainly consisting of theaflavine gallates and (-) epigallocatechin-3-gallate, inhibits phorbol ester tumor promoter 12-O tetradecanoylphorbol-13-acetate (TPA)-caused induction of these markers of inflammatory responses in murine skin. Topical application of BTP (6 mg in 0.2 ml acetone/animal) 30 min prior to TPA application on to the mouse skin resulted in significant inhibition against TPA-caused induction of epidermal edema (40%, P < 0.01), hyperplasia (57%, P < 0.005), leukocytes infiltration (50%), and induction of epidermal ODC (57%) and pro-inflammatory cytokine IL-1alpha mRNA expression (69%). Pre-application of BTP to that of TPA also resulted in significant inhibition of TPA-caused induction of epidermal ODC (23-73%, P < 0.005-0.0001), and cyclo-oxygenase, in terms of prostaglandins metabolites formation (38-65%, P < 0.01-0.0005), enzyme activities. Our data indicate that the inhibition of TPA caused changes in these markers of inflammatory responses in murine skin by BTP may be one of the possible mechanisms of chemopreventive effects associated with black tea against tumorigenesis. The results of this study suggest that black tea, specifically polyphenols present therein, may be useful against cutaneous inflammatory responses in human population. PMID- 9364000 TI - Association of chromosome 12p genetic polymorphisms with lung adenocarcinoma risk and prognosis. AB - The mapping near Kras2 of pulmonary adenoma susceptibility 1 (Pas1), a major locus affecting inherited predisposition to lung cancer in mice prompted us to test the homologous human region (12p12) for association with lung adenocarcinoma, by a population-based study. We genotyped 213 lung adenocarcinoma patients and 219 healthy blood donor subjects for five polymorphic markers mapping in the putative region of interest. Three marker polymorphisms, located in a region spanning approximately 700 kb, were significantly associated with lung adenocarcinoma risk. Furthermore, polymorphisms in KRAS2 and PTHLH loci were also associated with tumor prognosis. These results suggest the existence of a human Pas1 homologous locus on chromosome 12p12. PMID- 9364001 TI - Inhibition by piroxicam of oxidative DNA damage, liver cirrhosis and development of enzyme-altered nodules caused by a choline-deficient, L-amino acid-defined diet in rats. AB - Previously, we have reported that aspirin, a cyclooxygenase (COX) inhibitor, can prevent the fibrosis, cirrhosis and generation of oxidative DNA damage, and the associated development of glutathione-S-transferase placental form (GST-P) positive preneoplastic liver nodules, caused by a choline-deficient, L-amino acid defined (CDAA) diet in rats. In the present study, in order to elucidate the role of COX pathway in liver lesion-induction by a CDAA diet, the modulatory effects of other distinct chemical classes of COX inhibitors were examined. A long-acting example, piroxicam (PIRO) (at doses of 0.01, 0.02, 0.04 and 0.06%) and the short acting ibuprofen (IBU) (at doses of 0.02, 0.04 and 0.06%) and indomethacin (IND) (at doses of 0.005 and 0.008%) were administered in the CDAA diet to male F344 rats, and animals were killed after 12 and 30 weeks. In another experiment, IND was given in drinking water at doses of 0.001, 0.002 and 0.004%. None of the inhibitors affected the development of fatty liver caused by a CDAA diet, but PIRO at doses higher than 0.04%, strongly inhibited the development of GST-P positive and neoplastic nodules as well as fibrosis, cirrhosis and formation of 8 hydroxydeoxyguanosine (8-OHdG) adducts. IBU at the highest dose also exhibited similar but much less pronounced inhibitory effects. With IND, there was only a tendency for inhibition with no clear dose-dependence. The results together with our previous findings, indicate that relatively strong COX inhibitors, acting irreversibly like aspirin or for extended periods like PIRO, can prevent the endogenous hepatocarcinogenesis associated with a CDAA diet, although not the development of a fatty liver, suggesting that an augmented COX pathway might play key roles in the causation of liver lesions in this model. PMID- 9364002 TI - Assessment of the human exposure to heterocyclic amines. AB - Heterocyclic amines are possible human carcinogens and fried meat is an important source of exposure in the Western diet. To study the effect of heterocyclic amines in humans, accurate assessment of individual food consumption is essential. Parameters influencing the intake include the amount and type of meat ingested, frequency of consumption, cooking method, cooking temperature and the duration of cooking. The aim of the present study was to develop a practical method for assessing individual intakes of specific heterocyclic amines in a large sample of people. This has been done by combining information on food consumption and laboratory findings of heterocyclic amines in food products. Diet was assessed using a semi-quantitative food frequency questionnaire including photos of fried meat and, in all, 22 dishes were cooked and chemically analyzed. The method was employed in an elderly population in Stockholm to estimate the daily mean intake of the five heterocyclic amines 2-amino-3-methylimidazo[4,5 f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8 dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5 f]quinoxaline (DiMeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). The total daily intake ranged from none to 1816 ng, with a mean intake of 160 ng, which is well below estimates reported previously. Highest amounts ingested were of PhIP (mean 72, range 0-865 ng/day) and MeIQx (mean 72, range 0 1388 ng/day), followed by DiMeIQx (mean 16, range 0-171 ng/day), while MeIQ and IQ were ingested only in very small amounts (mean <1 ng/day). PMID- 9364003 TI - Reduction in formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) induced aberrant crypt foci in the rat colon by docosahexaenoic acid (DHA). AB - Docosahexaenoic acid (DHA), a major component of fish oil, suppresses the formation and growth of aberrant crypt foci induced by 1,2-dimethylhydrazine and azoxymethane. In the present study we examined the effects of intragastric gavage administration of DHA on the yield of rat colonic aberrant crypt foci due to treatment with a heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo[4,5 b]pyridine (PhIP), which induces colon cancer in male F344 rats and is considered to be a possible human colon carcinogen. Male F344 rats were given a standard diet (AIN-76A) and received 10 doses of PhIP (75 mg/kg body wt, by intragastric intubation, on days 1-5 and 8-12) with or without intragastric application of 1 ml DHA 4 h prior to each carcinogen treatment, followed by further DHA dosing. The numbers of PhIP-induced aberrant crypt foci per colon after 4 and 12 weeks DHA administration were significantly reduced to 47 and 38% respectively of the values obtained when PhIP alone was used. The mean number of aberrant crypts per focus was also decreased by DHA treatment. At week 4 the PhIP-DNA adduct levels in the colon of rats from the PhIP+DHA group were approximately two thirds of the PhIP group value. The results thus suggest that DHA exerts a preventive effect on PhIP-induced colon carcinogenesis. PMID- 9364004 TI - Feeding mice palm carotene prevents DNA damage in bone marrow and reduction of peripheral leukocyte counts, and enhances survival following X-ray irradiation. AB - This study examined the effects of palm carotene feeding on DNA damage of bone marrow, recovery of peripheral leukocyte counts, and the survival of mice that received whole-body X-ray irradiation. The palm carotene was composed of alpha- and beta-carotene in a ratio of 1:3. Mice were fed either a basal diet or a carotene diet (50 mg carotene/100 g diet) for 2 weeks, then irradiated. The carotene diet was prepared by the dietary protocol that markedly enhanced the accumulation of carotene in tissues (J. Nutr. 125, 3081, 1995). DNA damage in bone marrow was evaluated by micronucleus assay using peripheral blood. When mice received X-ray (1.5 Gy), marked DNA damage in bone marrow and reduction of peripheral leukocyte count were observed. These changes were significantly attenuated in mice fed the carotene diet. In addition, X-ray (6.5 Gy)-induced survival of mice fed the carotene diet was higher than those fed the basal diet. In mice fed the carotene diet, alpha- and beta-carotene were detected in bone marrow and liver, and concentration of vitamin A in liver was about four times higher compared with that in mice fed the basal diet. These findings suggest that feeding mice palm carotene prevents radiation-induced damages by way of its antioxidant activity and/or vitamin A activity. PMID- 9364005 TI - Identification of tamoxifen-DNA adducts formed by 4-hydroxytamoxifen quinone methide. AB - Tamoxifen is a liver carcinogen in rats and has been shown to increase the risk of endometrial cancer in women. Recent reports of DNA adducts in leucocyte and endometrial samples from women treated with tamoxifen indicate that it may be genotoxic to humans. One of the proposed pathways for the metabolic activation of tamoxifen involves oxidation to 4-hydroxytamoxifen, which may be further oxidized to an electrophilic quinone methide. In the present study we show that 4 hydroxytamoxifen quinone methide reacts with DNA to form covalent adducts. The major products, which result from 1,8-addition of the exocyclic nitrogen of deoxyguanosine to the conjugated system of 4-hydroxytamoxifen quinone methide, are characterized as (E)- and (Z)-alpha-(deoxyguanosin-N2-yl)-4-hydroxytamoxifen. PMID- 9364006 TI - Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung. AB - Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic hydrocarbon, is the most potent carcinogen ever tested in mouse skin and rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction, tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in strain A/J mouse lung. Groups of mice received a single i.p. injection of 0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment, DNA adducts were measured at times between 1 and 28 days, while tumors were counted at 250 days and analyzed for the occurrence of point mutations in codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung induced six major and four minor DNA adducts. Maximal levels of adduction occurred between 5 and 10 days after injection followed by a gradual decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti- and syn-11,12-dihydroxy-13,14-epoxy- 11,12,13,14 tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed by cochromatography. The major adduct was identified as a product of the reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced significant numbers of lung adenomas in a dose dependent manner, with the highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based on the administered dose, DB[a,l]P was more active than other environmental carcinogens including benzo[a]pyrene. As a function of time-integrated DNA adduct levels, DB[a,l]P induced lung adenomas with about the same potency as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar in carcinogenic potency to other PAHs in the strain A/J mouse lung model. Analysis of the Ki-ras mutation spectrum in DB[a,l]P-induced lung tumors revealed the predominant mutations to be G-->T transversions in the first base of codon 12, A-->G transitions in the second base of codon 12, and A-->T transversions in the second or third base of codon 61, concordant with the DNA adduct profile. PMID- 9364008 TI - Comparison of the morphological transforming activities of dibenzo[a,l]pyrene and benzo[a]pyrene in C3H10T1/2CL8 cells and characterization of the dibenzo[a,l]pyrene-DNA adducts. AB - C3H10T1/2CL8 (C3H10T1/2) mouse embryo fibroblasts were used to study the in vitro carcinogenic activities of dibenzo[a,l]pyrene (DB[a,l]P) and benzo[a]pyrene (B[a]P). The morphological transforming activities of these rodent carcinogens were compared using replicate concentration-response studies. In concentration ranges where both polycyclic aromatic hydrocarbons (PAHs) were active, DB[a,l]P proved to be four to 12 times as potent as B[a]P based on concentration. At lower concentrations DB[a,l]P was active at 0.10 and 0.20 microM, concentrations where B[a]P was inactive. This makes DB[a,l]P the most potent non-methylated PAH evaluated to date in C3H10T1/2 cells. DNA adducts of DB[a,l]P in C3H10T1/2 cells were analyzed by both TLC and TLC/HPLC 32P-postlabeling methods using mononucleotide 3'-phosphate adduct standards derived from the reactions of anti DB[a,l]P-11,12-diol-13,14-epoxide (anti-DB[a,l]PDE) and syn-DB[a,l]P-11,12-diol 13,14-epoxide (syn-DB[a,l]PDE) with deoxyadenosine 3'-monophosphate and deoxyguanosine 3'-monophosphate. All of the DNA adducts observed in C3H10T1/2 cells treated with DB[a,l]P were identified as being derived from the metabolism of DB[a,l]P to its fjord region diol epoxides through DB[a,l]P-11,12-diol. The predominant adduct was identified as an anti-DB[a,l]PDE-deoxyadenosine adduct. Other major adducts were anti-DB[a,l]PDE-deoxyguanosine and syn-DB[a,l]PDE deoxyadenosine adducts with minor amounts of syn-DB[a,l]PDE-deoxyguanosine adducts. These DNA adduct data are consistent with similar findings of DB[a,l]PDE deoxyadenosine adducts in mouse skin studies and human mammary cells in culture. PMID- 9364007 TI - Computerized image analysis of morphologically transformed and nontransformed Syrian hamster embryo (SHE) cell colonies: application to objective SHE cell transformation assay scoring. AB - We have developed an automated image analysis system that provides comparable classification of morphologically transformed SHE cell colonies to the current visual classification method used in the in vitro SHE cell transformation assay. Visual classification of morphologic transformation in this assay has been shown to accurately predict the carcinogenic potential of chemical, biological and physical agents. The image analysis system is quantitative, based on measuring features of colony color, texture and growth patterns. A linear combination of feature measurements produces a classification process that agrees with visual assessment 93% of the time. All identifiable sources of error are explored and the method is found to be robust in analyzing nearly 500 colonies from a variety of studies performed over a one year period. The high degree of correlation between the visual classification and the objective measurements of the image analysis system validates the reproducibility of the visual scoring process and serves as a basis for automation of the assay. PMID- 9364009 TI - Absence of metabolism of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) by flavin-containing monooxygenase (FMO). AB - The N-nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent lung carcinogen present in tobacco and tobacco smoke. Carbonyl reduction, alpha-carbon hydroxylation (activation) and N-oxidation of the pyridyl ring (detoxification) are the three main pathways of metabolism of NNK. In this study, metabolism of NNK was studied with lung and liver microsomes from F344 rats, Syrian golden hamsters and pigs and cloned flavin-containing monooxygenases (FMOs) from human and rabbit liver. Thermal inactivation at 45 degrees C for 2 min reduced FMO S-oxygenating activity but did not affect N-oxidation of NNK, leading to the conclusion that FMOs are not implicated in the detoxification of NNK. Detoxification of NNK was not increased by n-octylamine or by incubation at pH 8.4, supporting the conclusion that FMOs are not involved in the metabolism of NNK. SKF-525A (1 mM) significantly reduced N-oxidation and alpha-carbon hydroxylation, suggesting that these two pathways were catalyzed by cytochromes P450. Metabolism of NNK was lower with lung microsomes than with liver microsomes. Inhibition of metabolism of NNK by SKF-525A was also observed with rat lung microsomes, leading to the conclusion that cytochromes P450 are involved in pulmonary metabolism of NNK. Cloned FMOs did not metabolize NNK. In conclusion, cytochromes P450 rather than FMOs are involved in N-oxidation of NNK. The high capacity of hamster liver microsomes to activate NNK does not correlate with the resistance of this tissue to NNK-induced hepatocarcinogenesis. PMID- 9364010 TI - Marmoset CYP1A2: primary structure and constitutive expression in livers. AB - Complementary DNA of marmoset CYP1A2 was isolated by means of screening the cDNA library and reverse-transcriptase polymerase chain reaction. The deduced amino acid sequence of marmoset CYP1A2 consisted of 516 residues and showed 88.2 and 90.0% identities to corresponding forms in human and cynomolgus monkey, respectively. S1 nuclease protection assay demonstrated that CYP1A2 mRNA was expressed constitutively in the liver, but not in the lung, kidney and small intestine. The level of CYP1A2 mRNA in the liver was increased by treatment with 3-methylcholanthrene and polychlorinated biphenyls. Marmoset CYP1A2 expressed in recombinant yeast activated 2-amino-3-methylimidazo [4,5-f]quinoline (IQ) and 2 amino-3,8-dimethylimidazo [4,5-f]quinoxaline (MeIQx) efficiently, and also activated 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP), but at a relatively lower rate in the umu mutagenicity test. Marmoset CYP1A2 also showed ethoxyresorufin O-de-ethylase activity. Based on these results, we demonstrate that marmosets constitutively express CYP1A2 in the liver as in humans. PMID- 9364011 TI - Characterization of four N-3-thymidine adducts formed in vitro by the reaction of thymidine and butadiene monoxide. AB - Four products were characterized from the reaction of thymidine with butadiene monoxide (BM), a known human mutagen and possible human carcinogen. These products were purified by HPLC and characterized as diastereomeric pairs of N-3 (1-hydroxy-3-buten-2-yl)thymidine and N-3-(2-hydroxy-3-buten-1-yl)thymidine based upon their UV spectra, 1H NMR and fast atom bombardment mass spectra. Incubation of thymidine with an excess of BM at pH 7.4 and 37 degrees C allowed calculation of the pseudo-first-order kinetic rate constants for the adduct formation, but when these rate constants were compared with the rates we previously determined with guanosine, adenosine and deoxycytidine, the results suggested a lower reactivity with thymidine in comparison with the other nucleosides. When incubations were carried out at lower BM concentrations, the formation of adducts appeared to be linearly dependent on BM concentration. The four thymidine adducts were completely stable for 1 week when incubated at 37 degrees C in pH 7.4 phosphate buffer. These results suggest that the interactions of BM with thymidine may play a role in the molecular mechanisms of mutagenesis and carcinogenesis of BM. PMID- 9364012 TI - Microsome-mediated bioactivation of dibenzo[a,l]pyrene and identification of DNA adducts by 32P-postlabeling. AB - Dibenzo[a,l]pyrene (DBP) is one of the most potent bacterial mutagen and mammary carcinogens. When DBP (50 microM) was incubated with calf thymus DNA (300 microg/ml) in the presence of liver microsomes from beta-naphthoflavone (beta-NF) or Aroclor 1254-treated rats, at least eight adduct spots were detected as analyzed by nuclease P1-enhanced 32P-postlabeling assay. DNA adduction was enhanced by nearly 20- and 60-fold with beta-NF- and Aroclor 1254-induced microsomes, respectively, as compared with uninduced microsomes, suggesting a possible involvement of CYP1A family in DBP activation. Inclusion of the selective P4501A1 inhibitor, alpha-naphthoflavone (50 microM) in the activation reaction almost completely (>98%) abolished adduct formation further supporting involvement of P4501A in DBP activation. Analysis of DNA and 2'-deoxynucleosides 3'-mononucleotide reacted with anti- and syn-DBP-11,12-diol-13,14-epoxides (DBPDEs) and co-chromatography analyses in multiple solvents showed that the microsomal DBP-DNA adducts were derived by interaction of both anti- and syn DBPDEs with adenine and guanine in DNA in the following order: anti-DBPDE-dA approximately syn-DBPDE-dG >> anti-DBPDE-dG approximately syn-DBPDE-dA. It is concluded that (i) most or all DBP adducts were P4501A-mediated; (ii) both the anti- and syn-stereoisomers were involved in the DNA adduct formation; and (iii) both adenine and guanine in the DNA contributed equally to the formation of the major and minor adducts. PMID- 9364013 TI - Proliferative lesions of oviduct and uterus in CD-1 mice exposed prenatally to tamoxifen. AB - Tamoxifen (TAM) is widely used as adjuvant breast cancer therapy after surgery and as a chemopreventive agent in women of child-bearing age. However, TAM therapy has been shown to result in an increased incidence of endometrial carcinoma in women. The present study was designed to investigate the effects of TAM (5 mg/kg and 7.5 mg/kg body wt) given i.g. to pregnant CD-1 mice (1x/day, days 12 through 18 of gestation) on their female offspring. Progressive proliferative hyperplasia of the oviduct was frequently seen in TAM-exposed offspring, reaching 100% incidence by 52 weeks in both treatment groups. These females also developed progressive proliferative uterine lesions, including moderate/severe cystic endometrial hyperplasia (34-50%) and polypoid adenomas (27 30%) between 53 and 78 weeks. Deciduomas (15%) occurred at young ages (12 and 24 weeks) while leiomyomas (14%), a malignant leiomyosarcoma, and ovarian granulosa cell tumors (14%), were found between 72 and 78 weeks. Our findings thus suggest a strong association between transplacental TAM and reproductive tract abnormalities in female CD-1 mice. PMID- 9364014 TI - Studies of chemopreventive effects of budenoside on benzo[a]pyrene-induced neoplasia of the lung of female A/J mice. AB - The objective of the present investigation was to determine conditions under which the synthetic glucocorticoid, budenoside, will inhibit benzo[a]pyrene (BaP) induced pulmonary carcinogenesis when administered in the post-initiation period. For this purpose, female A/J mice were employed. The animals were given three administrations of 2 mg of BaP by oral intubation during a 1-week period. Budenoside was fed in the diet subsequent to the last dose of BaP. Using this format, two experiments were carried out to determine the effects of varying the time of administration of budenoside on the magnitude of the inhibition obtained. In both experiments, one group of mice was fed budenoside (1.5 mg/kg of diet) from 1 week after the last dose of BaP until the termination of the experiment, 15 weeks later. The reduction of pulmonary tumor formation under these conditions was 89% in the first experiment and 78% in the second (average 84%). In the first experiment the effects of feeding budenoside only during weeks 1-5 after BaP administration was studied. Under these conditions, inhibition of pulmonary tumor formation was 35%. In the second experiment, the effects of postponing the start of feeding budenoside was determined. In mice in which the budenoside feeding was delayed until 5 weeks after the last dose of BaP and then continued for the duration of the protocol, a 67% inhibition of tumor formation was found. The data obtained indicate that budenoside will produce inhibition of pulmonary adenoma formation when fed either early or late in the post-initiation stage of carcinogenesis, and that feeding throughout the entire post-initiation period gives maximum inhibition. PMID- 9364015 TI - Simple identification of dominant p53 mutants by a yeast functional assay. AB - Analysis of families with germline p53 mutations shows that the mutant p53 allele behaves as a dominant oncogene at the genetic level, although it behaves as a recessive oncogene at the cellular level, since tumours invariably show mutation or loss of both wild-type alleles. At the biochemical level it is possible that some clinically important mutant p53 proteins may be carcinogenic through a dominant mechanism. We show that p53 mutants can be readily classified according to their dominant potential using a simple yeast functional assay. Wild-type p53 is constitutively expressed from a TRP1 vector, p53 mutants are expressed from an otherwise identical LEU2 vector and net transcriptional activity is scored using an ADE2-based reporter. Twenty seven p53 mutants were tested: 19 were recessive, i.e. gave white colonies, and eight showed dominant activity, i.e. gave pink/red colonies. This simple assay should facilitate studies on p53 dominance. PMID- 9364017 TI - Diving and swimming performance of white whales, Delphinapterus leucas: an assessment of plasma lactate and blood gas levels and respiratory rates. AB - The white whale Delphinapterus leucas is an exceptional diver, yet we know little about the physiology that enables this species to make prolonged dives. We studied trained white whales with the specific goal of assessing their diving and swimming performance. Two adult whales performed dives to a test platform suspended at depths of 5-300 m. Behavior was monitored for 457 dives with durations of 2.2-13.3 min. Descent rates were generally less than 2 m s-1 and ascent rates averaged 2.2-3 m s-1. Post-dive plasma lactate concentration increased to as much as 3.4 mmol l-1 (4-5 times the resting level) after dives of 11 min. Mixed venous PO2 measured during voluntary breath-holds decreased from 79 to 20 mmHg within 10 min; however, maximum breath-hold duration was 17 min. Swimming performance was examined by training the whales to follow a boat at speeds of 1.4-4.2 m s-1. Respiratory rates ranged from 1.6 breaths min-1 at rest to 5.5 breaths min-1 during exercise and decreased with increasing swim speed. Post-exercise plasma lactate level increased to 1.8 mmol l-1 (2-3 times the resting level) following 10 min exercise sessions at swimming speeds of 2.5-2.8 m s-1. The results of this study are consistent with the calculated aerobic dive limit (O2 store/metabolic rate) of 9-10 min. In addition, white whales are not well adapted for high-speed swimming compared with other small cetaceans. PMID- 9364016 TI - Interactive suppression of aberrant crypt foci induced by azoxymethane in rat colon by phytic acid and green tea. AB - Several epidemiological studies point to a strong correlation between nutrient composition of the diet and cancer of the colon. Phytic acid, present in grains, has been credited with reducing the risk of cancer of the colon. A number of reports are available indicating the benefits of green tea consumption in reducing the risk of stomach, lung and skin cancer, but little data are available on the effect of green tea in reducing the risk of colon cancer. Also, there are no studies on the combined effect of these compounds on colon tumorigenesis. Thus the primary objective of this investigation was to elucidate the combined effects of green tea and phytic acid on colonic preneoplastic lesions and the Phase II enzyme glutathione S-transferase. Fisher 344 male weanling rats were divided into nine groups of 15 rats each and fed the experimental diet for 13 weeks. Rats received two s.c. injections of azoxymethane in saline at 16 mg/kg body wt at 7 and 8 weeks of age. Rats received three levels (0, 1 and 2%) of phytic acid with three levels (0, 1 and 2%) of green tea within each phytic acid level in a 3 x 3 factorial experiment. Results indicate that while green tea had a marginal effect (P < 0.14), phytic acid significantly reduced the incidence of aberrant crypt foci (P < 0.008). The interaction between green tea and phytic acid was significant (P < 0.029 for distal and < 0.0168 for entire colon) and positive, pointing to a synergistic effect of green tea and phytic acid. PMID- 9364018 TI - In vivo performance of trunk muscles in tree frogs during calling. AB - We used high-speed video and electromyography (EMG) to measure in vivo performance of the trunk muscles (external obliques) in two related species of North American gray tree frogs, Hyla versicolor and Hyla chrysoscelis. Both species produce trilled calls with high sound intensity, but the sound pulse frequency within calls in H. chrysoscelis is twice that in H. versicolor. In both species, sound pulse frequency is directly correlated with the active contractions of the trunk muscles. The length trajectory during contraction and relaxation displays a saw-tooth pattern with a longer shortening phase compared with the lengthening phase. The longer time spent shortening may enhance power production, because the shortening phase is the active part of the cycle during which the muscle produces positive work. A similar total strain (approximately 21 % and approximately 19 % in H. versicolor and H. chrysoscelis respectively) is achieved in the first few pulses, and during subsequent pulses the muscle cycles with a reduced pulse strain (approximately 12 % and approximately 7.3 % in H. versicolor and H. chrysoscelis respectively). The higher pulse frequencies of H. chrysoscelis are thus associated with lower pulse strains. The EMG pattern is different in the two species. A single EMG stimulus occurs for each cycle in H. chrysoscelis, but two stimuli per cycle are found in H. versicolor. Indirect evidence suggests that the initial phase of shortening during a pulse is partly due to elastic recoil of the trunk. PMID- 9364019 TI - Endocardial endothelium in the avascular heart of the frog: morphology and role of nitric oxide. AB - Endocardial endothelial morphology and the physiological modulatory role of nitric oxide (NO) were studied in an in vitro preparation of the working intact heart of the frog Rana esculenta, which lacks coronary vasculature and is thus devoid of a coronary vascular endothelium. En face confocal scanning laser microscopy of samples of perfused fixed hearts demonstrated the presence of NO synthase as a cytoplasmic constituent of the endocardial endothelial cells. Stroke volume (as a measure of performance in paced frog hearts) and stroke work (as an index of systolic function) increased by approximately 5 % after inhibition of the NO-cGMP pathway with 10(-4 )mol l-1 NG-nitro-l-arginine methyl ester and by approximately 8 % after inhibition with 10(-6 )mol l-1 Methylene Blue. In contrast, stroke volume and stroke work decreased by approximately 22 % after activation of the NO-cGMP pathway with sodium nitroprusside (10(-4 )mol l 1), while 3-morpholinosydnonimine (5x10(-8) to 10(-5 )mol l-1) caused a decrease of between 15 and 30 % and 8-bromo-cGMP (10(-6 )mol l-1) a decrease of approximately 8 %. These responses were significantly attenuated after exposure of the ventricular luminal to Triton X-100 (0.05 %, 0.1 ml), which itself increased performance (by over 10 %) without detectable morphological changes. These results show that the endocardial endothelium of Rana esculenta produces amounts of NO sufficient to modulate ventricular performance. PMID- 9364020 TI - The effects of length trajectory on the mechanical power output of mouse skeletal muscles. AB - The effects of length trajectory on the mechanical power output of mouse soleus and extensor digitorum longus (EDL) muscles were investigated using the work loop technique in vitro at 37 degrees C. Muscles were subjected to sinusoidal and sawtooth cycles of lengthening and shortening; for the sawtooth cycles, the proportion of the cycle spent shortening was varied. For each cycle frequency examined, the timing and duration of stimulation and the strain amplitude were optimized to yield the maximum power output. During sawtooth length trajectories, power increased as the proportion of the cycle spent shortening increased. The increase in power was attributable to more complete activation of the muscle due to the longer stimulation duration, to a more rapid rise in force resulting from increased stretch velocity and to an increase in the optimal strain amplitude. The power produced during symmetrical sawtooth cycles was 5-10 % higher than during sinusoidal work loops. Maximum power outputs of 92 W kg-1 (soleus) and 247 W kg-1 (EDL) were obtained by manipulating the length trajectory. For each muscle, this was approximately 70 % of the maximum power output estimated from the isotonic force-velocity relationship. We have found a number of examples suggesting that animals exploit prolonging the shortening phase during activities requiring a high power output, such as flying, jet-propulsion swimming and vocalization. In an evolutionary context, increasing the relative shortening duration provides an alternative to increasing the maximum shortening velocity (Vmax) as a way to increase power output. PMID- 9364021 TI - Effects of vagal stimulation on swimbladder blood flow in the european eel Anguilla anguilla. AB - The influence of the vagus nerve on swimbladder blood flow in the European eel (Anguilla anguilla) was characterized by recording the changes in blood flow rate and blood pressure following stimulation of the vagus nerve. After electrical stimulation, blood flow in the swimbladder artery increased from 0.9 ml min-1 to 2.1 ml min-1. Video recordings of small vessels on the caudal side of the rete mirabile revealed an increase in erythrocyte velocity combined with a small vasodilation. This effect could not be blocked by injection of the -adrenergic antagonist phentolamine, the ss-adrenergic antagonist propranolol or the muscarinic cholinoceptor antagonist atropine. In all preparations with a high initial flow rate (>1.9 ml min-1), vagotomy resulted in a marked decrease in blood flow (by approximately 80 %). This effect was not observed in preparations with a low initial swimbladder blood flow. Stimulation of the vagus nerve produced a decrease, and vagotomy produced an increase, in perfusion pressure in blood-perfused swimbladder preparations. Histological studies revealed the presence of a ganglion in the vagus nerve located on the anterior part of the resorbing section of the swimbladder close to the origin of the ductus pneumaticus, which is probably associated with swimbladder function. These results suggest that swimbladder blood flow, at least to some extent, is under vagal tonic control. The effects do not, however, appear to involve the classical - and ss-adrenergic or muscarinic cholinoceptor functions. PMID- 9364022 TI - Flow and flexibility. I. Effects Of size, shape and stiffness in determining wave forces on the stipitate kelps eisenia arborea and pterygophora californica AB - Wave action on exposed rocky coasts can be severe, generating large hydrodynamic forces that have been proposed to constrain the size of intertidal animals and plants. In contrast, flows subtidally are more benign, and organisms, particularly seaweeds, may grow quite large. The large dimensions of these flexible macroalgae allow them to move during much or most of a passing wave cycle, reducing relative water velocities and modifying the forces the plants must endure. The consequences of such wave-induced motion are explored for the stipitate understory kelps Eisenia arborea and Pterygophora californica using a numerical model that approximates these seaweeds as vertically oriented cantilever beams subjected to lateral hydrodynamic forces acting at their stipe tips. Bending moments and peak stresses induced in the stipes of these species during the passage of waves are calculated as functions of plant size and shape and of water depth and sea state. Model predictions for a subset of conditions are validated against real-time measurements of bending moments acting on a Pterygophora individual in the field. The results suggest that the allometric patterns of growth exhibited by Eisenia and Pterygophora can greatly reduce the stresses generated in the stipes of these plants relative to isometric growth. Low stipe stiffness acts as a general, particularly effective, stress-lowering mechanism. The dynamic swaying associated with this low stiffness can also modulate the magnitudes of peak stresses induced in the stipes of these kelps. In particular, in shallow water under large waves, dynamic loading can substantially increase induced stress, suggesting that plant motion is an important factor affecting the loading regime encountered by these organisms. PMID- 9364023 TI - Flow and flexibility. II. The roles of size and shape in determining wave forces on the bull kelp nereocystis luetkeana AB - Giant kelps (which may reach lengths of 45 m) are a prominent exception to the general rule that wave-swept organisms are small. The ability of these kelps to maintain their large size in the presence of ocean waves has been attributed to their extreme flexibility and the concomitant tendency to 'go with the flow', a tendency that reduces the hydrodynamic forces imposed on the plant. However, the flexibility of giant kelps carries with it the potential for the organism to apply an inertial load to its own structure if the blade mass reaches the end of its tether. Here, we examine the complex trade-off between flexibility and inertial loading using a simple computational model of the bull kelp Nereocystis luetkeana. In field and laboratory tests, the model accurately predicts the forces and motions imposed on flexible structures in wave-induced flows. Subsequent predictions from the model suggest that mature N. luetkeana can indeed benefit from moving with the flow, but that the forces imposed on juveniles are actually increased by the plant's flexibility. Furthermore, the benefit accrued from going with the flow is sensitive to the shape of the plant. If the bull kelp were to grow while maintaining a juvenile shape, the stress placed on its stipe would be drastically increased by dynamic loading, and these inappropriately shaped plants would be subjected to a high risk of breakage. For certain combinations of wave height, wave period and stipe length, the increased stress in hypothetical 'small'-shaped plants may be associated with chaotic motion of the blade mass. PMID- 9364024 TI - The effects of walls, paternity and ageing on sperm motility. AB - The measurement of sperm motility is critical when studying fertilization kinetics and chemotaxis. Analysis of motility has traditionally been carried out on cells in small fluid volumes on microscope slides. Several theoretical treatments suggest that drag forces significantly affect flagellar motion within 10 sperm body lengths of the slide surface. Understanding how sperm move in the absence of surface drag is crucial when considering natural locomotory patterns. To examine the effects of solid surfaces, motile sperm from sea urchins (Arbacia punctulata) were placed in a Plexiglas chamber (69 mmx45 mmx15.5 mm; length x width x height). A system was constructed to minimize convective flow by limiting temperature differences within the chamber to less than 0.1 degrees C. The movement of sperm was video-recorded at two levels: (3/4)100 micron (3 body lengths) and 5 mm (150 body lengths) below the chamber lid. When swimming speeds were measured using a computerized video motion-analysis system, a highly significant difference (P<0. 0001) between cells at the two depths was found. Cells nearest the lid swam at 174.6+/-5.9 micron s-1 (mean +/- s.e.m.), whereas those farther away slowed to only 111.1+/-9.9 micron s-1 (mean +/- s.e.m.). Swimming speed was also found to be significantly (P<0.01) affected by paternity, but not by sperm age. We conclude that viscous wall effects must be carefully considered in studies of sperm motility and chemotaxis. The analysis of sperm on a microscope slide may substantially exaggerate swimming speed. PMID- 9364025 TI - The effect of reduced gravity on the kinematics of human walking: a test of the dynamic similarity hypothesis for locomotion. AB - To gain insight into the basic principles that govern the biomechanics of locomotion, we investigated the effect of reduced gravity on walking kinematics. We hypothesized that humans walk in a dynamically similar fashion at combinations of speed and simulated gravity that provide equal values of the Froude number, v2/gLleg, where v is forward speed, g is gravitational acceleration and Lleg is leg length. The Froude number has been used to predict the kinematics and kinetics of legged locomotion over a wide range of animal sizes and speeds, and thus provides a potentially unifying theory for the combined effects of speed, size and gravity on locomotion biomechanics. The occurrence of dynamic similarity at equal Froude numbers has been attributed previously to the importance of gravitational forces in determining locomotion mechanics. We simulated reduced gravity using a device that applies a nearly constant upward force to the torso while subjects walked on a treadmill. We found that at equal Froude numbers, under different levels of gravity (0.25g-1.0g), the subjects walked with nearly the same duty factor (ratio of contact time to stride time), but with relative stride lengths (Ls/Lleg, where Ls is stride length) that differed by as much as 67 %, resulting in the rejection of our hypothesis. To understand the separate effects of speed and gravity further, we compared the mechanics of walking at the same absolute speed at different levels of gravity (0.25g-1.0g). In lower gravity, subjects walked with lower duty factors (10 %) and shorter relative stride lengths (16 %). These modest changes in response to the fourfold change in gravity indicate that factors other than gravitational forces are the primary determinants of walking biomechanics. PMID- 9364026 TI - Renal function and plasma levels of arginine vasotocin during free flight in pigeons. AB - We examined urinary water loss and plasma levels of arginine vasotocin (AVT) in free-flying, tippler pigeons trained to fly continuously for up to 5 h. First, we used [3H]polyethyleneglycol ([3H]PEG) as a glomerular filtration marker by implanting an osmotic minipump into each bird. In two flights (10 birds in winter at an ambient temperature of 13-15 degrees C and seven in summer at 23 degrees C), we measured pre-flight (hydrated, resting control birds) and post-flight [3H]PEG activity and osmolality in blood and ureteral urine. For comparison, we measured these variables in 10 birds in winter before and after controlled dehydration (24 h at 25 or 30 degrees C). Second, we measured plasma levels of AVT in 6-8 birds before and immediately after each of three different summer flights. Urine osmolality increased significantly by up to three times the control level in both post-flight and dehydrated pigeons; urine:plasma osmolality ratios did not exceed 2. Compared with controls, glomerular filtration rate (GFR) was significantly lower after flight in summer, but did not change in either post flight or dehydrated winter pigeons. In winter, mean post-flight urine flow rate (UFR) decreased significantly to less than half the control level, while in summer, post-flight UFR did not differ from control levels. In general, mean filtered water reabsorption (FrH2O) increased from 95 % in controls to 98 % in post-flight and dehydrated birds. Plasma levels of AVT increased after flight to between three and eight times the preflight levels. The data from this first study of kidney function during flight are consistent with previous studies of dehydration in birds and exercise in mammals in which both increased FrH2O and decreased GFR contribute to renal conservation of water. PMID- 9364027 TI - Migration and bidirectional phototaxis in Dictyostelium discoideum slugs lacking the actin cross-linking 120 kDa gelation factor. AB - Three mutant strains of Dictyostelium discoideum, lacking different actin-binding proteins, were tested for behavioural deficits in the multicellular pseudoplasmodium (slug) stage. Two strains, defective in the production of either -actinin (an actin cross-linker) or severin (an actin capping and severing protein), did not show changes in slug behaviour. Slugs of the mutant lacking another actin cross-linker, the 120 kDa gelation factor (ABP-120), however, migrated shorter distances in darkness as well as in horizontally directed light. More remarkably, they migrated at an angle of approximately 45 degrees to the left or right of the incident light, whereas wild-type slugs migrated on fairly straight paths towards the light. We discuss the hypothesis that this bidirectional oblique-angle phototaxis is due to changes in the optical properties of the pseudoplasmodia. Normally, in wild-type slugs, a lens effect causes stronger stimulation on the side distal to the incident light. We propose that in the mutant the lens quality is reduced, so that at small angles between the slug axis and the rays of light the proximal side is stimulated more intensely. As a result, the intended symmetrical stimulation is achieved at a certain angle to the left or right of the incident light. We assume that the absence of ABP-120 alters the shape of the lens and/or enhances internal light scattering via degradation of intercellular coherence; however, intracellular attenuation of light remains an additional or alternative possibility. PMID- 9364028 TI - FMRFamide-like peptides in the crayfish (Procambarus clarkii) stomatogastric nervous system: distribution and effects on the pyloric motor pattern. AB - Whole-mount immunocytochemistry was used to map the location of FMRFamide-like peptides in the crayfish (Procambarus clarkii) stomatogastric nervous system. This system contains the pyloric and gastric mill central pattern generators, which receive modulatory inputs from projection neurons with somata located primarily in other ganglia of the stomatogastric nervous system. Our studies revealed stained somata in the commissural and esophageal ganglia. A pair of stained somata was located in the inferior ventricular nerve, and another pair of somata was located in the stomatogastric nerve where it is joined by the two superior esophageal nerves. The stomatogastric ganglion contained no stained somata, but the neuropil was brightly stained and 2-4 axons projected laterally in small nerves directly from the ganglion. These results indicate that FMRFamide or related peptides may act as neuromodulators in the crayfish stomatogastric nervous system. To test this hypothesis, we studied the effects of FMRFamide and four related peptides (DF2, NF1, F1 and LMS) on the pyloric motor pattern. DF2, NF1 and F1 all excited certain pyloric cells, especially the lateral pyloric (LP) and ventricular dilator (VD) neurons, and enhanced pyloric cycling frequency in most actively rhythmic preparations. FMRFamide had no detectable effects on pyloric cells, and LMS had inhibitory effects, causing disruption of the pyloric rhythm in actively cycling preparations and reducing tonic activity in non rhythmic preparations. PMID- 9364029 TI - MeV-ion microprobe analyses of whole Drosophila suggest that zinc and copper accumulation is regulated storage not deposit excretion. AB - We examined Drosophila spp. using a penetrative ion microprobe technique that allows us to quantify element contents in whole organs and organisms. Comparatively non-penetrative techniques, such as electron microscopy, could not have been used to make many of these measurements because material is lost during sectioning. We found that zinc was accumulated predominantly within a single organ: in the main segments of both the anterior and posterior Malpighian tubules. In contrast to zinc, iron and copper were more generally distributed throughout the body. Zinc concentrations as high as 2.8 % of dry mass were measured in cell-sized volumes of the Malpighian tubules. The large quantities of zinc (approximately 2x10(-8) g in 8-day-old male adults) were sequestered by an unidentified mechanism. We found less than 1 % of the estimated amount of consumed zinc and copper in the abdomen of flies fed food containing several hundred parts per million dry mass of these metals. Our results are inconsistent with the detoxification hypothesis that predicts that a large proportion of the heavy metals passing through the gut are absorbed and stored permanently. We found for both zinc and copper that the quantity in the abdomen was not proportional to the concentration of these metals in the consumed food but was, instead, relatively invariant. For these reasons, we suggest that regulated biological availability, not detoxification, may be the primary benefit of zinc and copper storage. PMID- 9364030 TI - Regulation of ecdysis-triggering hormone release by eclosion hormone. AB - Ecdysis behavior in the tobacco hornworm Manduca sexta (Lepidoptera: Sphingidae) is triggered through reciprocal peptide signaling between the central nervous system and the epitracheal endocrine system. Recent evidence indicates that eclosion hormone may initiate endocrine events leading to ecdysis through its action on epitracheal glands to cause the release of ecdysis-triggering hormone (ETH). Here, we report that direct exposure of epitracheal glands to eclosion hormone in vitro leads to secretion of ETH. The threshold concentration of eclosion hormone needed to evoke release of ETH is approximately 3 pmol l-1. Eclosion hormone also induces elevation of cyclic GMP, but not cAMP, concentration in epitracheal glands at concentrations similar to those causing release of ETH. Both cGMP and 8-Br-cGMP mimic the secretory action of eclosion hormone. The sensitivity of the secretory response to eclosion hormone occurs during a narrow window of development, beginning approximately 8 h prior to pupal ecdysis. However, eclosion hormone can cause elevation of cGMP levels in epitracheal glands long before they acquire competence to release ETH, showing that the initial portion of the signal transduction cascade is in place early in development, but that the absence of a downstream step in the cascade prevents secretion. Measurements of cGMP levels in epitracheal glands during the ecdysis sequence show a sudden elevation some 30 min after the onset of pre-ecdysis, well after ETH secretion has been initiated. ETH secretion can therefore be viewed as a two-step process, beginning at pre-ecdysis when cGMP levels are relatively low, followed by a massive release resulting from a logarithmic elevation of cGMP levels. PMID- 9364031 TI - Low density lipoproteins (LDL) heterogeneity and intravenous fat in neonates. AB - BACKGROUND: The properties of iv-fat emulsions are similar to those of triglyceride-rich plasma lipoproteins and rapidly hydrolyzed by lipoprotein lipase. Neonates frequently do not tolerate iv-fat because of low levels of the key enzymes for fat metabolism. PURPOSE OF THE STUDY: We examined the effect of iv-fat therapy on LDL subclass distribution of 20 neonates unable to tolerate enteral feeding. METHODS: Particle size was determined by non-denaturing gradient gel electrophoresis. RESULTS: The LDL size distribution profiles at baseline showed unexpected diversity in the position of the major lipoprotein peak with three different profiles identified by peak position; profile I with a major peak of large-sized LDL (26.3-28.2 nm), profile II with a major peak at 25.2-26.7 nm and profile III with a major peak of small-sized particles (24.9-25.6 nm). None of the profiles fit the classical LDL pattern A or B found in adult plasma since the skewness associated with the adult pattern was not present. With iv fat feeding and enteral nutrition, no major shift in peak position was observed, even though plasma triglyceride and apo B concentrations increased suggesting that there was an increased number of LDL particles rather than an increase in the size of particles. CONCLUSION: The constancy of the LDL peak position in the face of increases in plasma triglyceride and apo B concentrations during iv fat and the onset of enteral nutrition in neonates suggests that other metabolic events, such as hormone status and lipid and transfer protein activities need to be considered. PMID- 9364032 TI - Aerosol production and aerosol droplet size distribution during mechanical ventilation (IPPV) with a new ultrasonic nebulizer. AB - Administration of drugs via the airway is increasingly practiced in ICU- and surgical patients. For this purpose, aerosols may be produced by either jet nebulization or ultrasonic droplet generation. In mechanically ventilated patients, aerosol delivery is often insufficient. The influence of the ventilatory pattern on nebulizer efficacy is poorly understood. In the present in vitro study we determined the efficacy of a new ultrasonic nebulizer in delivering aerosolized epoprostenol using defined ventilator settings. We determined aerosol delivery rates, the aerosol droplet size distribution and the impact of the connection tubing on drug delivery, applying adult and infant ventilation patterns. Aerosol production rates ranged from 0.28 to 0.57 ml per minute. Using an adult ventilator setting volume controlled ventilation (CMV) led to a higher aerosol production rate than pressure controlled ventilation (PCV) at identical tidal volumes and mean airway pressures (0.57 ml/min,CMV vs 0.39 ml/min, PCV). With an infant ventilator setting, nebulizer rates were lower than those found for the adult ventilator setting, but did not differ substantially between CMV and PCV mode (0.29 ml/min, CMV vs 0.28 ml/min, PCV). Aerosol delivery rates distal to the endotracheal tube changed according to aerosol production rates (adult mode: 0.18 ml/min, CMV vs 0.10 ml/min, PCV; infant mode: 0.03 ml/min, both CMV and PCV). In the infant ventilation mode, a higher percentage of the aerosol was trapped in the catheter mount as compared to the adult ventilation mode. Mass median droplet diameters for each of the four ventilator settings were almost identical (4.63 to 5.09 micron) and smaller than indicated in the product specifications (8 micron). Delivery rates and sizes of droplets delivered by the new ultrasonic nebulizer SUN 345(R) agree well with previously reported data from comparable settings using diverse nebulizer devices. PMID- 9364033 TI - High intensity transient signals (HITS) in patients with carotid artery disease. AB - Interest in the Doppler ultrasound phenomenon of "High Intensity Transient Signals" (HITS) is based on the, thus far, unproven hypothesis, that these signals may to some extent represent silent cerebral microembolism ahead of a TIA/stroke and hence identify patients at risk for stroke. We prospectively investigated 80 patients with 102 moderate/severe internal carotid artery lesions. Patients with additional potential sources of cerebral ischemia were excluded. Bilateral transcranial Doppler monitorings of the middle cerebral arteries (MCA) were performed for =>30 min. HITS occurred more often in patients with completed stroke (21.9%) than in patients with transient ischemic deficits (12.5%), but significantly less in asymptomatic subjects (4.3%) (p<0.05). The incidence was maximal in patients examined within the first week after the onset of stroke. HITS were significantly more often associated with severe (> 70%) (23.5%) than with moderate (50 - 70%) internal carotid artery stenosis (3.4%) (p<0.05). These figures are closely related to annual stroke risk estimates recently reported about patients evaluated in multi-centre trials for carotid endarterectomy, and support the concept that HITS associated with carotid disease represent an important individual risk predictor. PMID- 9364034 TI - Procalcitonin in diagnosis of severe infections. AB - Increased serum concentration of procalcitonin (PCT) in limited number of paediatric patients with acute severe bacterial infections has been described previously. In a prospective study in 337 hospitalised adult patients fulfilling the SIRS-criteria, serum PCT was determined on admission and up to 9 days thereafter. Patients with microbiologically documented infection showed peak values of 30 ng/ml at day 3, which rapidly decreased to normal levels. Patients without sepsis revealed baseline values (0.1 ng/ml or lower). The validity criteria were calculated for several breakpoints of PCT. We detected an interval from 0.1 to 0.5 ng/ml under which a severe microbial infection is unlikely (sensitivity 91%, specificity 25%, positive predictive value 39%, negative predictive value 86%). An infection is most likely above 0.5 ng/ml (sensitivity 60%, specificity 79%, positive predictive value 61%, negative predictive value 78%). Between these two points an infection can neither be confirmed nor excluded. The excellent specificity and negative predictive value at a cut-off point of 0.5 ng/ml suggests that this test might be a useful parameter in the management of infectious diseases. PMID- 9364035 TI - Intermittent edema of the upper and lower extremities and the abdominal wall caused by membranous stenosis of the superior vena cava and membranous obstruction of the inferior vena cava. AB - We report on a 38-year-old patient with intermittent edema of the lower legs, arms and abdominal wall. The cause for his tendency to develop edema was a membranous obstruction of the inferior vena cava and a membranous stenosis of the superior vena cava. The etiology of these anomalies of the vena cava suggests a congenital malformation. In consideration of the cases of inferior and/or superior vena cava-anomalies published to date the patient received an anticoagulant therapy (coumarin) and treatment with graduated compression stockings. He now complains from time to time of a sensation tension in the lower legs after prolonged standing or sitting. Edema of the upper and lower extremities and the abdominal wall have disappeared. PMID- 9364036 TI - Enhancement of 5-fluorouracil cytotoxicity by folinic acid in different cell lines of human renal cell carcinoma. AB - Results of cytotoxic chemotherapy in metastatic renal cell carcinoma are not impressive. Remission rates range between 0 and 20%. One of the substances which show a marginal effect is 5-fluorouracil (5-FU). The cytotoxicity of 5-FU can be modulated by combination with folinic acid as shown in various cell lines and clinical trials. We were interested to see whether such a biomodulation also occurs in renal cell cancer. The antiproliferative effect of 5-fluorouracil on two human cell lines of RCC and its potentiation by folinic acid was investigated in a monolayer proliferation assay. It could be shown that folinic acid enhanced the cytotoxic potential of 5-FU 6-8-fold. Our results indicate that the combination of these two drugs in the treatment of metastatic renal cell cancer might lead to better response rates. PMID- 9364037 TI - Late pulmonary impairment following allogeneic bone marrow transplantation. AB - The pulmonary function of 88 consecutive leukemic patients who had undergone allogeneic bone marrow transplantation (BMT) was studied beforehand, at 3 months, at 6 months, and annually thereafter until 5 years after grafting. The parameters for function which are indicative for obstructive and restrictive lung disease deteriorated in all patient groups during the first 3 to 6 months after BMT but partially recovered within one year. Long-term decline in lung function was similar in all patient groups, and neither the onset nor the magnitude of pulmonary dysfunction was related to the occurrence of pulmonary impairment within 6 months after grafting. Multivariate analysis was then employed to assess predictors for long-term pulmonary disease. Despite the obvious effect of chronic graft versus host disease on the course of lung function, it was in itself not a significant predictor of long-term pulmonary outcome. Rather, the conditioning regimen turned out to be indicative; compared with busulfan, fractionated total body irradiation was demonstrated to be clearly superior with a lower incidence of both restrictive and obstructive long-term lung impairment. Our data indicate a previously unknown long-term side effect of busulfan conditioning. PMID- 9364038 TI - A novel cell cycle-dependent antinuclear antibody in a patient with a monoclonal gammopathy of unknown significance. AB - A patient with a monoclonal gammopathy, an erosive polyarthritis and a spastic paraparesis of both legs revealed a high titer of antinuclear antibodies with an immunofluorescence pattern hitherto unknown. A pleomorphic staining pattern of unsynchronized cells suggested a cell cycle-dependent autoantigen. Cell cycle dependency of the antigen was confirmed by staining tissue sections, serum starvation of tissue culture cells and mitogen-stimulation of peripheral blood lymphocytes. The antinuclear antibody does not belong to the paraprotein fraction of the serum immunoglobulins. PMID- 9364039 TI - Effect of dietary fatty acids on jejunal and ileal oleic acid uptake by rat brush border membrane vesicles. AB - To test the effect of dietary fatty acids on fatty acid uptake, the influx kinetics of a representative long-chain fatty acid, 3H-oleic acid, in both the jejunum and ileum of rats has been studied using brush border membrane vesicles (BBMV). Animals were fed with semipurified diets containing 5 g fat/100 g diet, as corn oil (control group), safflower oil (unsaturated group) and coconut oil hydrogenated (saturated group). With increasing unbound oleate concentration in the medium, the three dietary groups showed saturable kinetics in both jejunal and ileal BBMV (controls: Vmax = 0.15 +/- 0.01 nmol x mg protein-1 x 5 min-1 and Km = 136 +/- 29.1 nmol for jejunum, and Vmax = 0.23 +/- 0.03 nmol x mg protein-1 x 5 min-1 and Km = 196 +/- 50.3 nmol for ileum; unsaturated: Vmax = 0.28 +/- 0.05 nmol x mg protein-1 x 5 min-1 and Km = 242.7 +/- 91.8 nmol for jejunum, and Vmax = 1.29 +/- 0.06 nmol x mg protein-1 x 5 min-1 and Km = 509.8 +/- 97.5 nmol for ileum; saturated: Vmax = 0.03 +/- 0.01 nmol x mg protein-1 x 5 min-1 and Km = 124.5 +/- 72.6 nmol for jejunum, and Vmax = 0.04 +/- 0.01 nmol x mg protein -1.5 min-1 and Km = 205.6 +/- 85.3 nmol for ileum). These results support the theory that feeding an isocaloric diet containing only unsaturated fatty acids enhanced oleic acid uptake, and feeding an isocaloric diet containing only saturated fatty acids decreased oleic acid uptake. The results obtained in the present work also show the adaptative ability of jejunum and ileum to the type of dietary fat. PMID- 9364040 TI - Knock-out mice reveal a critical antiepileptic role for neuropeptide Y. AB - Neuropeptide Y (NPY) inhibits excitatory synaptic transmission in the hippocampus and is implicated in control of limbic seizures. In the present study, we examined hippocampal function and the response to pharmacologically induced seizures in mutant mice lacking this peptide. In slice electrophysiology studies, no change in normal hippocampal function was observed in NPY-deficient mice compared with normal wild-type littermates. Kainic acid (KA) produced limbic seizures at a comparable latency and concentration in NPY-deficient mice compared with littermates. However, KA-induced seizures progressed uncontrollably and ultimately produced death in 93% of NPY-deficient mice, whereas death was rarely observed in wild-type littermates. Intracerebroventricular NPY infusion, before KA administration, prevented death in NPY-deficient mice. These results suggest a critical role for endogenous NPY in seizure control. PMID- 9364041 TI - Epsilon subunit-containing acetylcholine receptors in myotubes belong to the slowly degrading population. AB - Two types of muscle acetylcholine receptors (AChRs) can be distinguished on the basis of their degradation rates and sensitivities to innervation, muscle activity, and agents elevating intracellular cAMP. The first type (Rs), is present in a stable form (degradation t1/2 = approximately 10 d) at the adult innervated neuromuscular junctions (NMJs). Rs can also exist in a less stable form (called accelerated Rs; t1/2 = approximately 3-5 d) at denervated NMJs and in aneurally cultured myotubes; agents that increase intracellular cAMP reversibly modulate Rs stability. The second type of AChR is a rapidly degrading receptor (Rr) expressed only in embryonic and noninnervated muscles. Rr can be stabilized by ATP and not by cAMP. This study tested the hypothesis that the degradation properties unique to the Rs are attributable to the presence of the epsilon subunit. Immunoprecipitation and Western blot analysis of AChRs extracted from rat muscle cells in tissue culture showed that AChRs recognized by antibodies against the epsilon subunit degraded as a single population with a half-life similar to that of the slow component, Rs, in these cells. In addition, as for Rs receptors in denervated NMJs and cultured muscle cell, the degradation rate of these epsilon-containing AChRs was stabilized by dibutyryl-cAMP. The data indicate that the epsilon-containing AChRs behave like Rs. Thus, the presence of the epsilon subunit is sufficient for selecting an AChR molecule to the Rs pool. PMID- 9364042 TI - Metabotropic glutamate receptor-mediated suppression of an inward rectifier current is linked via a cGMP cascade. AB - Glutamate, the neurotransmitter released by photoreceptors, excites horizontal cells and OFF-type bipolar cells by activating ionotropic receptors. This study investigated an additional action of glutamate in which it modulates a voltage gated ion channel in horizontal cells. We find that glutamate and APB (2-amino-4 phosphonobutyrate) produce a delayed and moderately prolonged suppression of an inward rectifier current (IRK+). This effect is proposed to occur via an APB sensitive metabotropic glutamate receptor (mGluR) because common agonists for the ionotropic or APB-insensitive mGluRs are ineffective and the APB-insensitive receptor antagonist alpha-methyl-4-carboxyphenylglycine (MCPG) does not block the actions of glutamate or APB. 8-Br-cGMP, 1-methyl-3-isobutylxanthine (IBMX), and atrial natriuretic peptide (ANP) but not 8-Br-cAMP mimic the suppression of IRK+. The effects of glutamate and APB are blocked by protein kinase inhibitors including Rp-8-pCPT-cGMPS, H-8, and H-7 as well as by ATPgammaS. We hypothesize that the APB receptor suppresses IRK+ via upregulation of cGMP and subsequent activation of a cGMP-dependent protein kinase. This pathway is likely regulated by an ATP-dependent phosphorylation. This is a novel signaling pathway for mGluRs and indicates that at least two distinct APB-activated pathways exist in the retina. Functionally, this APB receptor-mediated action found in horizontal cells would provide a means by which spatially restricted changes of glutamate, produced by local illumination of photoreceptors, could regulate IRK+ and consequently the response properties of these neurons. This would serve to adapt selectively retinal regions stimulated by small regions of the visual world. PMID- 9364043 TI - Inhibition of axonal growth by brefeldin A in hippocampal neurons in culture. AB - The outgrowth of neuronal processes involves a great increase in the surface area of the cell. The supply of membrane material necessarily must be coordinated with the demands for neurite growth. The selective growth of only one or two neurites at any given time during the development of polarity raises the possibility that the production of materials by the soma is limiting for growth (Dotti and Banker, 1987; Dotti et al., Goslin and Banker, 1990). To examine the role of the availability of membrane components during the development of polarity and axonal elongation, we treated neurons with brefeldin A, an antibiotic that disrupts the trafficking of vesicles from the Golgi complex to the plasma membrane. Treatment with brefeldin A (1 microg/ml) inhibited axonal growth within 0.5 hr; in unpolarized cells it prevented the formation of an axon. These results indicate that the availability of membrane components of Golgi-derived vesicles is required for axonal growth and hence the development of polarity. Inhibitors of protein and RNA synthesis also blocked axonal growth and the development of polarity, but over a much slower time course. This suggests that the full complement of proteins and mRNAs required for the initial development of polarity is present for several hours before polarity is actually established. PMID- 9364044 TI - Expression of voltage-gated potassium channels decreases cellular protein tyrosine phosphorylation. AB - Protein tyrosine phosphorylation by endogenous and expressed tyrosine kinases is reduced markedly by the expression of functional voltage-gated potassium (Kv) channels. The levels of tyrosine kinase protein and cellular protein substrates are unaffected, consistent with a reduction in tyrosine phosphorylation that results from inhibition of protein tyrosine kinase activity. The attenuation of protein tyrosine phosphorylation is correlated with the gating properties of expressed wild-type and mutant Kv channels. Furthermore, cellular protein tyrosine phosphorylation is reduced within minutes by acute treatment with the electrogenic potassium ionophore valinomycin. Because tyrosine phosphorylation in turn influences Kv channel activity, these results suggest that reciprocal modulatory interactions occur between Kv channel and protein tyrosine phosphorylation signaling pathways. PMID- 9364045 TI - Cyclin dependent kinase inhibitors and dominant negative cyclin dependent kinase 4 and 6 promote survival of NGF-deprived sympathetic neurons. AB - Neuronal apoptosis plays a critical role in both normal development and disease. However, the precise molecular events controlling neuronal apoptosis are not well understood. Previously, we hypothesized that cell cycle regulatory molecules function in controlling the apoptotic pathways of trophic factor-deprived neurons. To test this hypothesis, we used the RNA alphavirus Sindbis to express three known cyclin dependent kinase inhibitors (CKIs), p16(ink4), p21(waf/cip), and p27(kip1), and dominant negative mutant forms of four known G1 cyclin dependent kinases (CDKs), Cdk2, Cdk3, Cdk4, and Cdk6, in primary cultured rat superior cervical ganglion sympathetic neurons. We demonstrate that expression of each of the CKIs protects the postmitotic cultured neurons from apoptotic death evoked by withdrawal of NGF. In addition, we show that expression of dominant negative forms of Cdk4 or Cdk6, but not Cdk2 or Cdk3, protects NGF-deprived sympathetic neurons from death. Such findings suggest the participation of several CDKs and their cognate cyclins in a neuronal apoptotic pathway. PMID- 9364046 TI - Expression of neuroserpin, an inhibitor of tissue plasminogen activator, in the developing and adult nervous system of the mouse. AB - Neuroserpin is a serine protease inhibitor of the serpin family that has been identified as an axonally secreted glycoprotein in neuronal cultures of chicken dorsal root ganglia. To obtain an indication for possible functions of neuroserpin, we analyzed its expression in the developing and the adult CNS of the mouse. In the adult CNS, neuroserpin was most strongly expressed in the neocortex, the hippocampal formation, the olfactory bulb, and the amygdala. In contrast, most thalamic nuclei, the caudate putamen, and the cerebellar granule cells were devoid of neuroserpin mRNA. During embryonic development, neuroserpin mRNA was not detectable in neuroepithelia, but it was expressed in the differentiating fields of most CNS regions concurrent with their appearance. In the cerebellum, the granule cells and a subgroup of Purkinje cells were neuroserpin-positive during postnatal development. As a further step toward the elucidation of neuroserpin function, we performed a study to identify potential target proteases. In vitro, neuroserpin formed SDS-stable complexes and inhibited the amidolytic activity of tissue plasminogen activator, urokinase, and plasmin. In contrast, no complex formation with or inhibition of thrombin was found. Expression pattern and inhibitory specificity implicate neuroserpin as a candidate regulator of plasminogen activators, which have been suggested to participate in the modulation or reorganization of synaptic connections in the adult. During development, neuroserpin may attenuate extracellular proteolysis related to processes such as neuronal migration, axogenesis, or the formation of mature synaptic connections. PMID- 9364047 TI - Development of intrinsic and synaptic properties in a forebrain nucleus essential to avian song learning. AB - In male zebra finches, the lateral magnocellular nucleus of the anterior neostriatum (LMAN) is necessary for the development of learned song but is not required for the production of acoustically stereotyped (crystallized) adult song. One hypothesis is that the physiological properties of LMAN neurons change over development and thus limit the ability of LMAN to affect song. To test this idea, we used in vitro intracellular recordings to characterize the intrinsic and synaptic properties of LMAN neurons in fledgling [posthatch days (PHD) 22-32] and juvenile zebra finches (PHD 40-51) when LMAN lesions disrupt normal song development, and in adults (>PHD 90) when LMAN lesions are without effect. In fledglings, depolarizing currents caused LMAN projection neurons to fire bursts of action potentials because of a putative low-threshold calcium spike (LTS). In contrast, juvenile and adult LMAN projection neurons fired accommodating trains of action potentials when depolarized but did not exhibit the burst mode of firing. Electrical stimulation of thalamic afferents elicited both monosynaptic EPSPs mediated by AMPA and NMDA receptors and polysynaptic IPSPs mediated by GABAA receptors from LMAN neurons at all ages studied here. In whole-cell voltage clamp recordings, the EPSCs (NMDA-EPSCs) consisted of fast and slow components. Unlike juvenile and adult NMDA-EPSCs, those in fledglings were dominated by the slower component. Thus, both the intrinsic and synaptic properties of LMAN neurons change markedly during early song development (PHD 22-40) and achieve several adult-like properties during early sensorimotor learning and well before the time when LMAN lesions no longer disrupt song development. PMID- 9364048 TI - Short-term changes in the Ca2+-exocytosis relationship during repetitive pulse protocols in bovine adrenal chromaffin cells. AB - Stimulus-secretion coupling was monitored with capacitance detection in bovine chromaffin cells recorded in perforated patch mode and stimulated with trains of depolarizing pulses. A subset of stimulus trains evoked a response with a Ca2+ exocytosis relationship identical to that obtained for single depolarizing pulses (Engisch and Nowycky, 1996). Other trains evoked responses with enhanced or diminished Ca2+ efficacy relative to this input-output function. The probability of obtaining a particular Ca2+-exocytosis relationship was correlated with the amount of Ca2+ entry per pulse, such that shorter pulses or smaller currents were associated with the greatest efficacy, and longer pulses and larger currents with the lowest efficacy. Apparent enhancements in Ca2+ efficacy were not caused by residual Ca2+ summing between pulses, because decreasing the interval between pulses usually reduced efficacy in the same cell; conversely, increasing the interval between pulses did not prevent an enhanced Ca2+-exocytosis relationship. Apparent decreases in Ca2+ efficacy were not caused by depletion of an available pool of release-ready vesicles, because an equivalent amount of total Ca2+ entry during a single long depolarizing pulse usually evoked a much larger secretory response in the same cell. Finally, there were no striking differences in global Ca2+ levels monitored with the fluorescent indicator Fura Red that could account for apparent changes in Ca2+ efficacy during repetitive stimulus protocols. It appears that in chromaffin cells, the Ca2+-exocytosis relationship is subject to activity-dependent changes during a stimulus train and can be modulated up or down from a basal state accessed by single pulse stimulations. PMID- 9364049 TI - Dendroaxonal transcytosis of transferrin in cultured hippocampal and sympathetic neurons. AB - Previous studies using overexpressed polymeric immunoglobulin receptor in cultured neurons have suggested that these cells may use a dendroaxonal transcytotic pathway (Ikonen et al., 1993; de Hoop et al., 1995). By using a combination of semiquantitative light microscopy, video microscopy, and a biochemical assay, we show that this pathway is used by the endogenous ligand transferrin (Tf) and its receptor. Labeled Tf added to fully mature hippocampal neurons changes the intracellular distribution of its receptor from preferentially dendritic shortly after addition to dendritic and axonal at longer times. Incubation of living neurons with (caged)FITC-Tf followed by uncaging in the dendrites results in the later appearance of fluorescence in the axon of the same cell. In "chambered" sympathetic neurons in culture, 125I-Tf or iron as 55Fe Tf added to the cell body/dendrite chamber is recovered in the axonal chamber, showing that internalized ligand from the cell body-dendrite area is released at the axonal end. Finally, we show that excitatory neurotransmitters increase Tf receptor transcytosis, whereas inhibitory neurotransmitters reduce it. The dendritic uptake, transcytotic transport, and axonal release of physiologically active Tf demonstrated here could be envisioned for other trophic factors and therefore have important consequences for neuronal anterograde target maturation. Moreover, the changes in transcytosis after neurotransmitter addition may be important in the cellular responses that follow electrical activation. PMID- 9364050 TI - Mutation causing autosomal dominant nocturnal frontal lobe epilepsy alters Ca2+ permeability, conductance, and gating of human alpha4beta2 nicotinic acetylcholine receptors. AB - A mutation (S247F) in the channel-lining domain (M2) of the alpha4 nicotinic acetylcholine receptor (AChR) subunit has previously been linked genetically to autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE). To better understand the functional significance of this mutation, we characterized the properties of mutant and wild-type human alpha4beta2 AChRs expressed in Xenopus oocytes. Both had similar expression levels and EC50 values for ACh and nicotine. Substantial use-dependent functional upregulation was found for mutant alpha4beta2 AChRs, but not for wild type. Mutant AChR responses showed faster desensitization, slower recovery from desensitization, less inward rectification, and virtually no Ca2+ permeability as compared with wild-type alpha4beta2 AChRs. Addition of the alpha5 subunit restored Ca2+ permeability to the mutant alpha4beta2alpha5 AChRs. At -80 mV, wild-type alpha4beta2 AChR single channel currents exhibited two conductances, each with two mean open times (gamma1 = 17 pS, tau1 = 3.7 msec, and tau2 = 23.4 msec; gamma2 = 28 pS, tau1 = 1.9 msec, and tau2 = 8.1 msec). In contrast, mutant AChRs exhibited only one conductance of 11 pS, with tau1 = 1.9 msec and tau2 = 4.1 msec. The net effect of the mutation is to reduce AChR function. This could result in the hyperexcitability characteristic of epilepsy if the mutant AChRs were part of an inhibitory circuit, e.g., presynaptically regulating the release of GABA. In the minority of AChRs containing the alpha5 subunit, the overall functionality of these AChRs could be maintained despite the mutation in the alpha4 subunit. PMID- 9364051 TI - Mechanism and kinetics of heterosynaptic depression at a cerebellar synapse. AB - High levels of activity at a synapse can lead to spillover of neurotransmitter from the synaptic cleft. This extrasynaptic neurotransmitter can diffuse to neighboring synapses and modulate transmission via presynaptic receptors. We studied such modulation at the synapse between granule cells and Purkinje cells in rat cerebellar slices. Brief tetanic stimulation of granule cell parallel fibers activated inhibitory neurons, leading to a transient elevation of extracellular GABA, which in turn caused a short-lived heterosynaptic depression of the parallel fiber to Purkinje cell EPSC. Fluorometric calcium measurements revealed that this synaptic inhibition was associated with a decrease in presynaptic calcium influx. Heterosynaptic inhibition of synaptic currents and calcium influx was eliminated by antagonists of the GABAB receptor. The magnitude and time course of the depression of calcium influx were mimicked by the rapid release of an estimated 10 microM GABA using the technique of flash photolysis. We found that inhibition of presynaptic calcium influx peaked within 300 msec and decayed in <3 sec at 32 degrees C. These results indicate that presynaptic GABAB receptors can sense extrasynaptic GABA increases of several micromolar and that they rapidly regulate the release of neurotransmitter primarily by modulating voltage-gated calcium channels. PMID- 9364052 TI - Pyruvate protects neurons against hydrogen peroxide-induced toxicity. AB - Hydrogen peroxide (H2O2) is suspected to be involved in numerous brain pathologies such as neurodegenerative diseases or in acute injury such as ischemia or trauma. In this study, we examined the ability of pyruvate to improve the survival of cultured striatal neurons exposed for 30 min to H2O2, as estimated 24 hr later by the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazoliumbromide assay. Pyruvate strongly protected neurons against both H2O2 added to the external medium and H2O2 endogenously produced through the redox cycling of the experimental quinone menadione. The neuroprotective effect of pyruvate appeared to result rather from the ability of alpha-ketoacids to undergo nonenzymatic decarboxylation in the presence of H2O2 than from an improvement of energy metabolism. Indeed, several other alpha-ketoacids, including alpha-ketobutyrate, which is not an energy substrate, reproduced the neuroprotective effect of pyruvate. In contrast, lactate, a neuronal energy substrate, did not protect neurons from H2O2. Optimal neuroprotection was achieved with relatively low concentrations of pyruvate (=1 mM), whereas at high concentration (10 mM) pyruvate was ineffective. This paradox could result from the cytosolic acidification induced by the cotransport of pyruvate and protons into neurons. Indeed, cytosolic acidification both enhanced the H2O2 induced neurotoxicity and decreased the rate of pyruvate decarboxylation by H2O2. Together, these results indicate that pyruvate efficiently protects neurons against both exogenous and endogenous H2O2. Its low toxicity and its capacity to cross the blood-brain barrier open a new therapeutic perspective in brain pathologies in which H2O2 is involved. PMID- 9364053 TI - Modulation of rod photoreceptor cyclic nucleotide-gated channels by tyrosine phosphorylation. AB - Cyclic nucleotide-gated (CNG) channels in vertebrate photoreceptors are crucial for transducing light-induced changes in cGMP concentration into electrical signals. In this study, we show that both native and exogenously expressed CNG channels from rods are modulated by tyrosine phosphorylation. The cGMP sensitivity of CNG channels, composed of rod alpha-subunits expressed in Xenopus oocytes, gradually increases after excision of inside-out patches from the oocyte membrane. This increase in sensitivity is inhibited by a protein tyrosine phosphatase (PTP) inhibitor and is unaffected by three different Ser/Thr phosphatase inhibitors. Moreover, it is suppressed or reversed by application of ATP but not by a nonhydrolyzable ATP analog. Application of protein tyrosine kinase (PTK) inhibitors causes an increase in cGMP sensitivity, but only in the presence of ATP. Taken together, these results suggest that CNG channels expressed in oocytes are associated with active PTK(s) and PTP(s) that regulate their cGMP sensitivity by changing phosphorylation state. The cGMP sensitivity of native CNG channels from salamander rod outer segments also increases and decreases after incubation with inhibitors of PTP(s) and PTK(s), respectively. These results suggest that rod CNG channels are modulated by tyrosine phosphorylation, which may function as a novel mechanism for regulating the sensitivity of rods to light. PMID- 9364054 TI - Altered trafficking of mutant connexin32. AB - We examined the cellular localization of nine different connexin32 (Cx32) mutants associated with X-linked Charcot-Marie-Tooth disease (CMTX) in communication incompetent mammalian cells. Cx32 mRNA was made, but little or no protein was detected in one class of mutants. In another class of mutants, Cx32 protein was detectable in the cytoplasm and at the cell surface, where it appeared as plaques and punctate staining. Cx32 immunoreactivity in a third class of mutants was restricted to the cytoplasm, where it often colocalized with the Golgi apparatus. Our studies suggest that CMTX mutations have a predominant effect on the trafficking of Cx32 protein, resulting in a potentially toxic cytoplasmic accumulation of Cx32 in these cells. These results and evidence of cytoplasmic accumulation of other mutated myelin proteins suggest that diseases affecting myelinating cells may share a common pathophysiology. PMID- 9364055 TI - In vitro ischemia promotes glutamate-mediated free radical generation and intracellular calcium accumulation in hippocampal pyramidal neurons. AB - Ischemia-induced cell damage studies have revealed a complex mechanism that is thought to involve glutamate excitotoxicity, intracellular calcium increase, and free radical production. We provide direct evidence that free radical generation occurs in rat CA1 pyramidal neurons of organotypic slices subjected to a hypoxic hypoglycemic insult. The production of free radicals is temporally correlated with intracellular calcium elevation, as measured by injection of fluo-3 in individual pyramidal cells, using patch electrodes. Free radical production (measured as changes in the fluorescence emission of dihydrorhodamine 123) peaked during reoxygenation and paralleled rising intracellular calcium. Electrophysiological whole-cell recordings revealed membrane potential depolarization and decreased input resistance during the ischemic insult. Glutamate receptor blockade resulted in decreased free radical production and markedly diminished intracellular calcium accumulation, and prevented neuronal depolarization and input resistance decrease during the ischemic episode. These results provide evidence for a direct involvement of glutamate in oxidative damage resulting from ischemic episodes. PMID- 9364056 TI - Phosphodiesterase I, a novel adhesion molecule and/or cytokine involved in oligodendrocyte function. AB - One of the more complex developmental processes occurring postnatally in the CNS is the formation of the myelin sheath by oligodendrocytes. To examine the molecular events that take place during myelination, we isolated oligodendrocyte derived cDNA clones, one of which (p421.HB) represents a putative alternatively spliced isoform of rat brain-specific phosphodiesterase I (PD-Ialpha) and a species homolog of the human cytokine autotaxin. Analysis of the structural composition of the p421.HB/PD-Ialpha protein suggests a transmembrane-bound ectoenzyme, which, in addition to the phosphodiesterase-active site contains presumed cell recognition and Ca2+-binding domains. Consequently, it may be involved in extracellular signaling events. Expression of p421.HB/PD-Ialpha is enriched in brain and spinal cord, where its mRNA can be detected in oligodendrocytes and in cells of the choroid plexus. Expression in the brain increases during development with an intermediate peak of expression around the time of active myelination and maximal expression in the adult. We have identified four presumably alternatively spliced isoforms, two of which appear to be CNS-specific. Decreased levels of p421.HB/PD-Ialpha mRNA in the dysmyelinating mouse mutant jimpy, but not shiverer, suggest a role for p421.HB/PD-Ialpha during active myelination and/or late stages of oligodendrocyte differentiation. Furthermore, p421.HB/PD-Ialpha mRNA levels were reduced in the CNS at onset of clinical symptoms in experimental autoimmune encephalomyelitis. These data together implicate the importance of p421.HB/PD-Ialpha in oligodendrocyte function, possibly through cell-cell and/or cell-extracellular matrix recognition. PMID- 9364057 TI - Developmental regulation of basket/stellate cell-->Purkinje cell synapses in the cerebellum. AB - We used paired recordings to study the development of synaptic transmission between inhibitory interneurons of the molecular layer and Purkinje cells in the cerebellar cortex of the rat. The electrophysiological data were combined with a morphological study of the recorded cells using biocytin or Lucifer yellow staining. Thirty-one interneuron-Purkinje cell pairs were obtained, and 11 of them were recovered morphologically. The age of the rats ranged from 11 to 31 d after birth. During this period synaptic maturation resulted in an 11-fold decrease in the average current evoked in a Purkinje cell by a spike in a presynaptic interneuron. Unitary IPSCs in younger animals exhibited paired-pulse depression, whereas paired-pulse facilitation was found in more mature animals. These data suggest that reduction in transmitter release probability contributed to the developmental decrease of unitary IPSCs. However, additional mechanisms at both presynaptic and postsynaptic loci should also be considered. The decrease of the average synaptic current evoked in a Purkinje cell by an action potential in a single interneuron suggests that as development proceeds interneuron activities must be coordinated to inhibit efficiently Purkinje cells. PMID- 9364058 TI - Absence of sensory neurons before target innervation in brain-derived neurotrophic factor-, neurotrophin 3-, and TrkC-deficient embryonic mice. AB - Gene-targeting experiments of Trk receptors and neurotrophins has confirmed the expectation that embryonic sensory and sympathetic neurons require neurotrophin function for survival. They have further revealed correlation between a specific neurotrophin requirement and eventual sensory modality. We have analyzed embryonic and neonatal mice with mutations in the BDNF, neurotrophin 3 (NT-3), and TrkC genes. Our data confirm an unexpectedly high proportion of sensory neuron losses in NT-3 (>70%), BDNF (>20%), and TrkC (>30%) mutants, which encompass populations thought to be NGF-dependent. Direct comparison of TrkC and NT-3 mutants indicates that only a subset of the NT-3-dependent neurons also requires TrkC. The observed losses in our TrkC mutant, which is null for all proteins encoded by the gene, are more severe than those previously reported for the kinase-negative TrkC mutation, implicating additional and important functions for the truncated receptors. Our data further indicate that mature NGF-requiring neurons undergo precocious and transitory requirements for NT-3 and/or BDNF. We suggest that neurotrophins may function in creating early heterogeneity that would enable ganglia to compensate for diverse modality requirements before the period of naturally occurring death. PMID- 9364059 TI - Transplanted oligodendrocyte progenitor cells expressing a dominant-negative FGF receptor transgene fail to migrate in vivo. AB - The proliferation, migration, survival, and differentiation of oligodendrocyte progenitor cells, precursors to myelin-forming oligodendrocytes in the CNS, are controlled by a number of polypeptide growth factors in vitro. The requirement and roles for individual factors in vivo, however, are primarily unknown. We have used a cell transplantation approach to examine the role of fibroblast growth factor (FGF) in oligodendrocyte development in vivo. A dominant-negative version of the FGF receptor-1 transgene was introduced into oligodendrocyte progenitors in vitro, generating cells that were nonresponsive to FGF but responsive to other mitogens. When transplanted into the brains of neonatal rats, mutant cells were unable to migrate and remained within the ventricles. These results suggest a role for FGF signaling in establishing a motile phenotype for oligodendrocyte progenitor cell migration in vivo and illustrate the utility of a somatic cell mutagenesis approach for the study of gene function during CNS development in vivo. PMID- 9364060 TI - Release sites and calcium channels in hair cells of the chick's cochlea. AB - Rapid transmitter release at synapses depends on the close proximity of voltage gated calcium channels (VGCCs). In mechanosensory hair cells of the vertebrate inner ear, dihydropyridine-sensitive VGCCs may be preferentially expressed at release sites to support transmitter release. In support of this hypothesis we have found that whole-cell current through VGCCs covaried with afferent innervation density among hair cells of the chick's basilar papilla (the avian analog of the mammalian Organ of Corti). The size as well as number of presynaptic dense bodies (PDBs) around which transmitter vesicles cluster varied systematically among equivalent populations of hair cells examined with electron microscopy. The total number of VGCCs was correlated with total release area (PDB cross-sectional area x the number of PDBs) among neurally located (tall) hair cells. Abneural, short hair cells with little or no afferent contact expressed a low number of VGCCs independent of release area. The implication is that hair cells augment calcium channel expression by adding release sites and by making release sites larger. This suggests further that aspects of hair cell excitability, such as electrical tuning, could depend on the synaptic architecture of each cell. PMID- 9364061 TI - Estradiol enhances prostaglandin E2 receptor gene expression in luteinizing hormone-releasing hormone (LHRH) neurons and facilitates the LHRH response to PGE2 by activating a glia-to-neuron signaling pathway. AB - Prostaglandin E2 (PGE2) mediates the stimulatory effect of norepinephrine (NE) on the secretion of luteinizing hormone-releasing hormone (LHRH), the neuropeptide controlling reproductive function. In rodents, this facilitatory effect requires previous exposure to estradiol, suggesting that the steroid affects downstream components in the cascade that leads to PGE2-induced LHRH release. Because astroglia are the predominant cell type contacting LHRH-secreting nerve terminals, we investigated the involvement of hypothalamic astrocytes in the estradiol facilitation of PGE2-induced LHRH release. A subpopulation of LHRH neurons was found to express the mRNA encoding the PGE2 receptor subtype EP1-R, which is coupled to calcium mobilization. The LHRH-producing cell line GT1-1 also contains EP1-R mRNA and, to a lesser extent, the three alternatively spliced forms of EP3-R mRNA (alpha, beta, and gamma) that encode receptors linked to inhibition and stimulation of cAMP formation. Hypothalamic astrocytes treated with estradiol produced a conditioned medium that when applied to GT1-1 cells resulted in a selective upregulation of EP1-R and EP3gamma-R mRNAs. The conditioned medium also enhanced the LHRH response to EP1-R and EP3-R agonists and the cAMP response to EP3-R activation. Thus, one mechanism by which estradiol facilitates the effect of neurotransmitters acting via PGE2 to stimulate LHRH release is by enhancing the glial production of substances that upregulate PGE2 receptors on LHRH neurons. The existence of such a mechanism underscores the emerging importance of glial-neuronal communication in the control of brain neurosecretory activity. PMID- 9364062 TI - Delayed reduction of ischemic brain injury and neurological deficits in mice lacking the inducible nitric oxide synthase gene. AB - Inducible nitric oxide synthase (iNOS), an enzyme that produces toxic amounts of nitric oxide, is expressed in a number of brain pathologies, including cerebral ischemia. We used mice with a null mutation of the iNOS gene to study the role of iNOS in ischemic brain damage. Focal cerebral ischemia was produced by occlusion of the middle cerebral artery (MCA). In wild-type mice, iNOS mRNA expression in the post-ischemic brain begun between 24 and 48 hr peaked at 96 hr and subsided 7 d after MCA occlusion. iNOS mRNA induction was associated with expression of iNOS protein and enzymatic activity. In contrast, mice lacking the iNOS gene did not express iNOS message or protein after MCA occlusion. The infarct and the motor deficits produced by MCA occlusion were smaller in iNOS knockouts than in wild type mice (p < 0.05). Such reduction in ischemic damage and neurological deficits was observed 96 hr after ischemia but not at 24 hr, when iNOS is not yet expressed in wild-type mice. The decreased susceptibility to cerebral ischemia in iNOS knockouts could not be attributed to differences in the degree of ischemia or vascular reactivity between wild-type and knockout mice. These findings indicate that iNOS expression is one of the factors contributing to the expansion of the brain damage that occurs in the post-ischemic period. iNOS inhibition may provide a novel therapeutic strategy targeted specifically at the secondary progression of ischemic brain injury. PMID- 9364063 TI - Mice deficient in the alpha7 neuronal nicotinic acetylcholine receptor lack alpha bungarotoxin binding sites and hippocampal fast nicotinic currents. AB - The alpha7 subunit of the neuronal nicotinic acetylcholine receptor (nAChR) is abundantly expressed in hippocampus and is implicated in modulating neurotransmitter release and in binding alpha-bungarotoxin (alpha-BGT). A null mutation for the alpha7 subunit was prepared by deleting the last three exons of the gene. Mice homozygous for the null mutation lack detectable mRNA, but the mice are viable and anatomically normal. Neuropathological examination of the brain revealed normal structure and cell layering, including normal cortical barrel fields; histochemical assessment of the hippocampus was also normal. Autoradiography with [3H]nicotine revealed no detectable abnormalities of high affinity nicotine binding sites, but there was an absence of high-affinity [125I]alpha-BGT sites. Null mice also lack rapidly desensitizing, methyllycaconitine-sensitive, nicotinic currents that are present in hippocampal neurons. The results of this study indicate that the alpha-BGT binding sites are equivalent to the alpha7-containing nAChRs that mediate fast, desensitizing nicotinic currents in the hippocampus. These mice demonstrate that the alpha7 subunit is not essential for normal development or for apparently normal neurological function, but the mice may prove to have subtle phenotypic abnormalities and will be valuable in defining the functional role of this gene product in vivo. PMID- 9364064 TI - Apoptosis-suppressor gene bcl-2 expression after traumatic brain injury in rats. AB - Neuronal death after experimental traumatic brain injury (TBI) has features of both apoptosis and necrosis. Neurons in the peritrauma cortex, hippocampus, and dentate gyrus are particularly vulnerable. The apoptosis-suppressor gene bcl-2 is induced in brain after ischemia and epilepsy-induced injury and may serve to regulate neuronal death. We studied expression of bcl-2 mRNA and protein after experimental TBI in rats. To determine whether bcl-2 protein expression occurred in cells with evidence of apoptosis, triple-labeling studies were performed using (1) antibody against bcl-2, (2) bis-benzimide dye to examine gross nuclear morphology, and (3) terminal deoxynucleotidyl transferase-mediated biotin-dUTP nick-end labeling (TUNEL) to assess for DNA fragmentation. At 6 and 24 hr, bcl-2 mRNA was induced in ipsilateral peritrauma cortex, hippocampus, and dentate gyrus. By 72 hr the increase in bcl-2 mRNA was detected only in cortex. bcl-2 protein was induced at 8, 24, 72, and 168 hr in ipsilateral cortex and hippocampus. Cells expressing bcl-2 protein included neurons in the peritrauma cortex, hippocampus, hilus, and dentate gyrus. The gross nuclear morphology of neurons expressing bcl-2 appeared normal. Furthermore, biochemical evidence of DNA fragmentation, in a pattern characteristic of either apoptosis or necrosis, was seldom seen in neurons expressing bcl-2 protein (bcl-2 colocalized with TUNEL in 0-2% of TUNEL-positive cells observed). These data suggest that bcl-2 may play an important role in the regulation of neuronal death after TBI, and they support a role for bcl-2 as an inducible neuroprotective gene. PMID- 9364065 TI - Neuronal and non-neuronal collapsin-1 binding sites in developing chick are distinct from other semaphorin binding sites. AB - The collapsin and semaphorin family of extracellular proteins contributes to axonal path finding by repulsing axons and collapsing growth cones. To explore the mechanism of collapsin-1 action, we expressed and purified a truncated collapsin-1-alkaline phosphatase fusion protein (CAP-4). This protein retains biological activity as a DRG growth cone collapsing agent and saturably binds to DRG neurons with low nanomolar affinity. Specific CAP-4 binding sites are present on DRG neurons, sympathetic neurons, and motoneurons, but not on retinal, cortical, or brainstem neurons. Outside the nervous system, high levels of CAP-4 binding sites are present in the mesenchyme surrounding major blood vessels and developing bone and in lung. These sites provide a substrate for the collapsin-1 dependent patterning of non-neuronal tissues perturbed in sema III (-/-) mice. The staining patterns for mouse semaphorin D/III and chick collapsin-1 fusion proteins are indistinguishable from one another but quite separate from that for semaphorin B and M-semaphorin F fusion proteins. These data imply that a family of high-affinity semaphorin binding sites similar in complexity to the semaphorin ligand family exists. PMID- 9364066 TI - A short-range signal restricts cell movement between telencephalic proliferative zones. AB - During telencephalic development, a boundary develops that restricts cell movement between the dorsal cortical and basal striatal proliferative zones. In this study, the appearance of this boundary and the mechanism by which cell movement is restricted were examined through a number of approaches. The general pattern of neuronal dispersion was examined both with an early neuronal marker and through the focal application of DiI to telencephalic explants. Both methods revealed that, although tangential neuronal dispersion is present throughout much of the telencephalon, it is restricted within the boundary region separating dorsal and ventral telencephalic proliferative zones. To examine the cellular mechanism underlying this boundary restriction, dissociated cells from the striatum were placed within both areas of the boundary, where dispersion is limited, and areas within the cortex, where significant cellular dispersion occurs. Cells placed within the boundary region remain round and extend only thin processes, whereas progenitors placed onto the cortical ventricular zone away from this boundary are able to migrate extensively. This suggests that the boundary inhibits directly the migration of cells. To examine whether the signal inhibiting dispersion within the boundary region acts as a long- or short-range cue, we apposed explants of boundary and nonboundary regions in vitro. Within these explants we found that migration was neither inhibited in nonboundary regions nor induced in boundary regions. This suggests that the boundary between dorsal and ventral telencephalon isolates these respective environments through either a contact-dependent or a short-range diffusible mechanism. PMID- 9364067 TI - Birthdate and cell marker analysis of scrambler: a novel mutation affecting cortical development with a reeler-like phenotype. AB - The reeler mutation in mice produces an especially well characterized disorder, with systematically abnormal migration of cerebral cortical neurons. The reeler gene encodes a large protein, termed Reelin, that in the cortex is synthesized and secreted exclusively in the Cajal-Retzius neurons of the cortical marginal zone (D'Arcangelo et al., 1995). In reeler mutant mice, loss of Reelin protein is associated with a systematic loss of the normal, "inside-out" sequence of neurogenesis in the cortex: neurons are formed in the normal sequence but become localized in the cortex in a somewhat inverted, although relatively disorganized "outside-in" pattern. Here we show that the scrambler mutant mouse exhibits a loss of lamination in the cortex and hippocampus that is indistinguishable from that seen in the reeler mouse. We use BrdU birthdating studies to show that scrambler cortex shows a somewhat inverted "outside-in" sequence of birthdates for cortical neurons that is similar to that previously described in reeler cortex. Finally, we perform staining with the CR-50 monoclonal antibody (Ogawa et al., 1995), which recognizes the Reelin protein (D'Arcangelo et al., 1997). We show that Reelin immunoreactivity is present in the scrambler cortex in a normal pattern, suggesting that Reelin is synthesized and released normally. Our data suggest that scrambler is a mutation in the same gene pathway as the reeler gene (Relnrl) and is most likely downstream of Relnrl. PMID- 9364068 TI - Glutamate transporter GLAST is expressed in the radial glia-astrocyte lineage of developing mouse spinal cord. AB - The glutamate transporter GLAST is localized on the cell membrane of mature astrocytes and is also expressed in the ventricular zone of developing brains. To characterize and follow the GLAST-expressing cells during development, we examined the mouse spinal cord by in situ hybridization and immunohistochemistry. At embryonic day (E) 11 and E13, cells expressing GLAST mRNA were present only in the ventricular zone, where GLAST immunoreactivity was associated with most of the cell bodies of neuroepithelial cells. In addition, GLAST immunoreactivity was detected in radial processes running through the mantle and marginal zones. From this characteristic cytology, GLAST-expressing cells at early stages were judged to be radial glia cells. At E15, cells expressing GLAST mRNA first appeared in the mantle zone, and GLAST-immunopositive punctate or reticular protrusions were formed along the radial processes. From E18 to postnatal day (P) 7, GLAST mRNA or its immunoreactivity gradually decreased from the ventricular zone and disappeared from radial processes, whereas cells with GLAST mRNA spread all over the mantle zone and GLAST-immunopositive punctate/reticular protrusions predominated in the neuropils. At P7, GLAST-expressing cells were immunopositive for glial fibrillary acidic protein, an intermediate filament specific to astrocytes. Therefore, the glutamate transporter GLAST is expressed from radial glia through astrocytes during spinal cord development. Furthermore, the distinct changes in the cell position and morphology suggest that both the migration and transformation of radial glia cells begin in the spinal cord between E13 and E15, when the active stage of neuronal migration is over. PMID- 9364069 TI - Differential effects of abnormal tactile experience on shaping representation patterns in developing and adult motor cortex. AB - This study investigates the influence of early somatosensory experience on shaping movement representation patterns in motor cortex. Electrical microstimulation was used to map bilaterally the motor cortices of adult rats subjected to altered tactile experience by unilateral vibrissa trimming from birth (birth-trimmed group) or for comparable periods that began in adulthood (adult-trimmed group). Findings demonstrated that (1) vibrissa trimming from birth, but not when initiated in adulthood, led to a significantly smaller-sized primary motor cortex (M1) vibrissa representation in the hemisphere contralateral to the trimmed vibrissae, with no evidence for concomitant changes in size of the adjacent forelimb representation or the representation of the intact vibrissae in the opposite (ipsilateral) hemisphere; (2) in the contralateral hemispheres of the birth-trimmed group, an abnormal pattern of evoked vibrissa movement was evident in which bilateral or ipsilateral (intact) vibrissa movement predominated; (3) in both hemispheres of the birth-trimmed group, current thresholds for eliciting movement of the trimmed vibrissa were significantly lower than normal; and (4) in the adult-trimmed group, but not in the birth trimmed group, there was a decrease bilaterally in the relative frequency of dual forelimb-vibrissa sites that form the common border between these representations. These results show that sensory experience early in life exerts a significant influence in sculpting motor representation patterns in M1. The mature motor cortex is more resistant to the type and magnitude of influence that tactile experience has on developing M1, which may indicate that such an influence is constrained by a developmentally regulated critical period. PMID- 9364070 TI - Subcortical input to the smooth and saccadic eye movement subregions of the frontal eye field in Cebus monkey. AB - We have recently identified two functional subregions in the frontal eye field (FEF) of the Cebus monkey, a smooth eye movement subregion (FEFsem) and a saccadic subregion (FEFsac). The thalamic input to these two subregions was studied and quantified to gain more information about the influence of the cerebellum and basal ganglia on the oculomotor control mechanisms of the cerebral cortex. A recent study using transneuronal transport of virus demonstrated that there are neurons in the basal ganglia and cerebellum that project to the FEFsac with only a single intervening synapse (Lunch et al., 1994). In the present study, we concentrated on the thalamic input to the FEFsem to define possible basal ganglia-thalamus-cortex and cerebellum-thalamus-cortex channels of information flow to the FEFsem. We localized the functional subregions using low threshold microstimulation, and retrogradely transported fluorescent tracers were then placed into the FEFsem and FEFsac. The neurons that project to the FEFsem are distributed in (1) the rostral portion of the ventral lateral nucleus, pars caudalis, (2) the caudal portion of the ventral lateral nucleus, pars caudalis, (3) the mediodorsal nucleus, (4) the ventral anterior nucleus, pars parvocellularis, and (5) the ventral anterior nucleus, pars magnocellularis. In contrast, the large majority of neurons that project to the FEFsac are located in the paralaminar region of the mediodorsal nucleus. The FEFsac and FEFsem thus each receive neural input from both basal ganglia-receiving and cerebellar receiving cell groups in the thalamus, but each receives input from a unique combination of thalamic nuclei. PMID- 9364071 TI - Synchronization of neuronal activity during stimulus expectation in a direction discrimination task. AB - The dorsal pathway of the primate brain, especially the middle temporal area (MT or V5) and the superior middle temporal area (MST or V5a), is strongly involved in motion detection. The relation between neural firing rates and psychophysical performance has led to the assumption that the neural code used by these areas consists of the relative discharge rates of neuronal populations. As an additional neural code, temporal correlation of neural activity has been suggested. Our study addresses the involvement of such a code in awake monkeys performing a motion discrimination task. We found significant temporal correlations between simultaneously recorded pairs of units in areas MT and MST and other extrastriate cortical areas. Units recorded from the same electrode were more frequently synchronized than units recorded from different electrodes placed within the same or different cortical areas. Activity synchronization was present in the expectation period before stimulus presentation and could not be induced de novo by the stimulus. Rather, we found a contrast-dependent reduction of correlation strength on stimulus onset. Correlation strength did not vary systematically with stimulus directions. We conclude that under the conditions of this study, temporal decorrelation of MT and MST neurons could be used to detect the stimulus, but synchronization does not convey specific information about its direction of motion and therefore is unlikely to contribute to performance in our direction discrimination task. Activity synchronization in the period before stimulus onset could be related to attentive expectation. PMID- 9364072 TI - Partial hippocampal kindling decreases efficacy of presynaptic GABAB autoreceptors in CA1. AB - The effect of partial hippocampal kindling, a model of temporal lobe seizure, on monosynaptic inhibition mediated by GABA was studied. Kindled rats were given 15 nonconvulsive hippocampal afterdischarges, and control rats were given low frequency or no stimulations. At 1-2 d after kindling, paired-pulse depression (PPD) of the IPSCs recorded in CA1 neurons in vitro was significantly smaller in kindled as compared with control rats. The difference in PPD persisted for at least 21 d after kindling. The decrease in PPD of the IPSCs after partial hippocampal kindling was likely caused by a reduced GABA autoinhibition after downregulation of presynaptic GABAB receptors. The GABAB antagonist CGP35348 (1 mM) suppressed PPD of the IPSCs more strongly in control than in kindled rats. Direct activation of the presynaptic GABAB receptors by baclofen suppressed the monosynaptic IPSCs significantly more in control than in kindled rats. The decay rate of a single-pulse IPSC was faster in kindled than in control rats on day 1 or day 21 after partial kindling. The difference in IPSC decay between kindled and control rats was found with or without a GABAB receptor antagonist. The low efficacy of the presynaptic GABAB receptors in kindled rats may provide compensatory stabilization of the postsynaptic membrane against further seizures or plasticity. PMID- 9364073 TI - Spatial relationships among three columnar systems in cat area 17. AB - In the primary visual cortex, neurons with similar response properties are arranged in columns. As more and more columnar systems are discovered it becomes increasingly important to establish the rules that govern the geometric relationships between different columns. As a first step to examine this issue we investigated the spatial relationships between the orientation, ocular dominance, and spatial frequency domains in cat area 17. Using optical imaging of intrinsic signals we obtained high resolution maps for each of these stimulus features from the same cortical regions. We found clear relationships between orientation and ocular dominance columns: many iso-orientation lines intersected the borders between ocular dominance borders at right angles, and orientation singularities were concentrated in the center regions of the ocular dominance columns. Similar, albeit weaker geometric relationships were observed between the orientation and spatial frequency domains. The ocular dominance and spatial frequency maps were also found to be spatially related: there was a tendency for the low spatial frequency domains to avoid the border regions of the ocular dominance columns. This specific arrangement of the different columnar systems might ensure that all possible combinations of stimulus features are represented at least once in any given region of the visual cortex, thus avoiding the occurrence of functional blind spots for a particular stimulus attribute in the visual field. PMID- 9364074 TI - Dissociable forms of inhibitory control within prefrontal cortex with an analog of the Wisconsin Card Sort Test: restriction to novel situations and independence from "on-line" processing. AB - Attentional set-shifting and discrimination reversal are sensitive to prefrontal damage in the marmoset in a manner qualitatively similar to that seen in man and Old World monkeys, respectively (Dias et al., 1996b). Preliminary findings have demonstrated that although lateral but not orbital prefrontal cortex is the critical locus in shifting an attentional set between perceptual dimensions, orbital but not lateral prefrontal cortex is the critical locus in reversing a stimulus-reward association within a particular perceptual dimension (Dias et al., 1996a). The present study presents this analysis in full and extends the results in three main ways by demonstrating that (1) mechanisms of inhibitory control and "on-line" processing are independent within the prefrontal cortex, (2) impairments in inhibitory control induced by prefrontal damage are restricted to novel situations, and (3) those prefrontal areas involved in the suppression of previously established response sets are not involved in the acquisition of such response sets. These findings suggest that inhibitory control is a general process that operates across functionally distinct regions within the prefrontal cortex. Although damage to lateral prefrontal cortex causes a loss of inhibitory control in attentional selection, damage to orbitofrontal cortex causes a loss of inhibitory control in affective processing. These findings provide an explanation for the apparent discrepancy between human and nonhuman primate studies in which disinhibition as measured on the Wisconsin Card Sort Test is associated with dorsolateral prefrontal damage, whereas disinhibition as measured on discrimination reversal is associated with orbitofrontal damage. PMID- 9364075 TI - Selective synaptic distribution of kainate receptor subunits in the two plexiform layers of the rat retina. AB - The synaptic localization of the kainate receptor subunits GluR6/7 and KA2 and of the ionotropic glutamate receptor subunits delta1/2 was studied in the rat retina using receptor-specific antisera. GluR6/7 and KA2 were present in both synaptic layers of the retina: the inner plexiform layer (IPL) and the outer plexiform layer (OPL). The localization of delta1/2 was restricted to the IPL. Detailed ultrastructural examination showed that in the OPL GluR6/7 was localized in horizontal cell processes postsynaptic to both rod spherules and cone pedicles. It was always only one of the two invaginating horizontal cell processes at the photoreceptor synapses labeled for GluR6/7. KA2 in the OPL was found only postsynaptic to cone pedicles and never postsynaptic to rod spherules. The KA2 labeled processes made flat contacts with the cone pedicles, suggesting they are the dendrites of OFF bipolar cells. In the IPL the different receptor subunits were localized postsynaptically to ribbon synapses of both rod and cone bipolar cells. As a rule, only one of the two postsynaptic elements at the bipolar cell dyad was stained for each of the receptor subunits examined. The selective and heterogeneous distribution of these receptors at the ribbon synapses of the OPL and IPL suggests a high degree of differential processing of the glutamatergic signals. PMID- 9364076 TI - CA3-driven hippocampal-entorhinal loop controls rather than sustains in vitro limbic seizures. AB - Continuous application of 4-aminopyridine (4-AP, 50 microM) to combined slices of hippocampus-entorhinal cortex obtained from adult mice induces (1) interictal discharges that initiate in the CA3 area and propagate via the hippocampal regions CA1 and subiculum to the entorhinal cortex and return to the hippocampus through the dentate gyrus; and (2) ictal discharges that originate in the entorhinal cortex and propagate via the dentate gyrus to the hippocampus proper. Ictal discharges disappear over time, whereas synchronous interictal discharges continue to occur throughout the experiment. Lesioning the Schaffer collaterals abolishes interictal discharges in CA1, entorhinal cortex, and dentate gyrus and discloses entorhinal ictal discharges that propagate, via the dentate gyrus, to the CA3 subfield. Interictal discharges originating in CA3 also prevent the occurrence of ictal events generated in the entorhinal cortex during application of Mg2+-free medium. In both models, ictal discharge generation recorded in the entorhinal cortex after Schaffer collateral cut is prevented by mimicking CA3 neuronal activity through rhythmic electrical stimulation (0.25-1.5 Hz) of the CA1 hippocampal output region. Our findings demonstrate that interictal discharges of hippocampal origin control the expression of ictal epileptiform activity in the entorhinal cortex. Sectioning the Schaffer collaterals may model the chronic epileptic condition in which cell damage in the CA3 subfield results in loss of CA3 control over the entorhinal cortex. Hence, we propose that the functional integrity of hippocampal output neurons may represent a critical control point in temporal lobe epileptogenesis. PMID- 9364078 TI - Detectability index measures of binaural masking level difference across populations of inferior colliculus neurons. AB - In everyday life we continually need to detect signals against a background of interfering noise (the "cocktail party effect"): a task that is much easier to accomplish using two ears. The binaural masking level difference (BMLD) measures the ability of listeners to use a difference in binaural attributes to segregate sound sources and thus improve their discriminability against interfering noises. By computing the detectability of tones from rate-versus-level functions in the presence of a suprathreshold noise, we previously demonstrated that individual low-frequency delay-sensitive neurons in the inferior colliculus are able to show BMLDs. Here we consider the responses of a population of such neurons when the noise level is held constant (as conventionally in psychophysical paradigms). We have sampled the responses of 121 units in the inferior colliculi of five guinea pigs to identical noise and 500 Hz tones at both ears (NoSo) and to identical noise but with the 500 Hz tone at one ear inverted (NoSpi). The result suggests that the neurons subserving detection of So tones in No (identical noise at the two ears) noise are those neurons with best frequencies (BFs) close to 500 Hz that respond to So tones with an increase in their discharge rate from that attributable to the noise. The detection of the inverted (Spi) signal is also attributable to neurons with BFs close to 500 Hz. However, among these neurons, the presence of the Spi tone was indicated by an increased discharge rate in some neurons and by a decreased discharge rate in others. PMID- 9364077 TI - Interaction between the postsubiculum and anterior thalamus in the generation of head direction cell activity. AB - Previous research has identified neurons in the postsubiculum (PoS) and anterior dorsal thalamic nucleus (AD) of the rat that discharge as a function of the animal's head direction. In addition, anatomical studies have shown that the AD and PoS are reciprocally connected with one another. The current study examined whether head direction (HD) cells in each of the two areas is dependent on input from the other structure. After both electrolytic or neurotoxic lesions of the AD, no cells were identified with direction-specific discharge in the PoS. In contrast, AD HD cell activity was still present after neurotoxic lesions to the PoS. However, AD HD cells in PoS-lesioned rats exhibited three important differences compared with AD HD cells in intact animals: (1) their directional firing range was significantly larger, (2) their firing predicted the animal's future head direction by a larger amount, and (3) their preferred firing direction was substantially less influenced by a prominent visual landmark within the recording environment. These results indicate that information critical for HD cell activity is conveyed in both directions between the AD and the PoS; whereas the AD is necessary for the presence of HD cell activity in the PoS, the PoS appears important in allowing visual landmarks to exert control over the preferred firing direction of AD HD cells. These findings have implications for several computational models that propose to account for the generation of the HD cell signal. PMID- 9364079 TI - Differential brainstem Fos-like immunoreactivity after laryngeal-induced coughing and its reduction by codeine. AB - We used the expression of the immediate-early gene c-fos, a marker of neuronal activation, to localize brainstem neuronal populations functionally related to fictive cough (FC). In decerebrate, paralyzed, and ventilated cats, the level of Fos-like immunoreactivity (FLI) was examined in five groups of animals: (1) controls, sham-operated unstimulated animals; (2) coughing cats, including both animals in which FC was elicited by unilateral electrical stimulation of the superior laryngeal nerve (SLN) and (3) those in which FC was elicited by bilateral SLN stimulation; (4) stimulated-treated cats, in which bilateral SLN stimulation was applied after selective blockade of FC by codeine; and (5) codeine controls, sham-operated unstimulated cats subjected to administration of codeine. Fifteen brainstem structures were compared for numbers of labeled cells. Because codeine selectively blocks FC, brainstem nuclei activated specifically during FC were identified as regions showing increased FLI after FC and significant reductions in FLI after FC suppression by codeine in stimulated treated cats. In coughing animals, we observed a selective immunoreactivity in the interstitial and ventrolateral subdivisions of the nucleus of the tractus solitarius, the medial part of the lateral tegmental field, the internal division of the lateral reticular nucleus, the nucleus retroambiguus, the para-ambigual region, the retrofacial nucleus, and the medial parabrachial nucleus. FLI in all these nuclei was significantly reduced in stimulated-treated cats. Our results are consistent with the involvement of neurons overlapping the main brainstem respiratory-related regions as well as the lateral tegmental field and the lateral reticular nucleus in the neural processing of laryngeal-induced FC. PMID- 9364080 TI - Evidence of contextual fear after lesions of the hippocampus: a disruption of freezing but not fear-potentiated startle. AB - The roles of the dorsal hippocampus and the central nucleus of the amygdala in the expression of contextual fear were assessed using two measures of conditioned fear: freezing and fear-potentiated startle. A discriminable context conditioning paradigm was developed that demonstrated both conditioned freezing and fear potentiated startle in a context paired previously with foot shock, relative to a context in which foot shock had never been presented. Post-training lesions of the central nucleus of the amygdala completely blocked both contextual freezing and fear-potentiated startle. Post-training lesions of the dorsal hippocampus attenuated contextual freezing, consistent with previous reports in the literature; however, these same lesions had no effect on fear-potentiated startle, suggesting preserved contextual fear. These results suggest that lesions of the hippocampus disrupt the freezing response but not contextual fear itself. PMID- 9364081 TI - Extracellular serotonin in the lateral hypothalamic area is increased during the postejaculatory interval and impairs copulation in male rats. AB - Serotonin (5-HT) is generally inhibitory to masculine sexual behavior. It has been suggested that 5-HT released after ejaculation may promote the sexual quiescence of the postejaculatory interval (PEI). The following experiments were conducted to test (1) whether extracellular 5-HT increases in either the anterior lateral hypothalamic area (LHAA) or the medial preoptic area (MPOA) of male rats after ejaculation; (2) whether increasing 5-HT in these sites, by microinjecting the selective serotonin reuptake inhibitor alaproclate, could inhibit copulatory abilities; and (3) whether copulation deficits produced by alaproclate were attributable to locomotor impairments. The effects of local application of alaproclate on extracellular 5-HT levels in the LHAA and the MPOA were also tested. Extracellular serotonin was measured in all experiments using in vivo microdialysis. Ejaculation was correlated with enhanced 5-HT release from the LHAA; no 5-HT increases were observed before ejaculation, and levels were decreased toward basal values during a subsequent copulatory series. Elevating 5 HT in the LHAA by microinjecting alaproclate inhibited copulation by increasing the latency to mount, intromit, and ejaculate. This inhibition did not result from nonspecific locomotor impairments. In the MPOA, 5-HT release remained stable throughout copulation, and microinjecting alaproclate into this site did not significantly alter sexual behavior. These data support the large body of evidence suggesting that 5-HT is inhibitory to masculine sexual behavior. Furthermore, the LHAA, but not the MPOA, may be one site responsible for serotonergic inhibition of copulation during the PEI. PMID- 9364082 TI - Interaction of GABA and excitatory amino acids in the basolateral amygdala: role in cardiovascular regulation. AB - Activation of the amygdala in rats produces cardiovascular changes that include increases in heart rate and arterial pressure as well as behavioral changes characteristic of emotional arousal. The objective of the present study was to examine the interaction of GABA and excitatory amino acid (EAA) receptors in the basolateral amygdala (BLA) in regulating cardiovascular function. Microinjection of the GABAA receptor antagonist bicuculline methiodide (BMI) or the E A A receptor agonists NMDA or AMPA into the same region of the BLA of conscious rats produced dose-related increases in heart rate and arterial pressure. Injection of the nonselective EAA receptor antagonist kynurenic acid into the BLA prevented or reversed the cardiovascular changes caused by local injection of BMI or the noncompetitive GABA antagonist picrotoxin. Conversely, local pretreatment with the glutamate reuptake inhibitor L-trans-pyrrolidine-2,4-dicarboxylic acid enhanced the effects of intra-amygdalar injection of BMI. The cardiovascular effects of BMI were also attenuated by injection of either the NMDA antagonist 3 (2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP) or the AMPA receptor antagonist 1,2,3,4-tetrahydro-6-nitro-2, 3-dioxo-benzo[f]quinoxaline-7 sulfonamide (NBQX). When these two EAA receptor antagonists were combined, their ability to suppress BMI-induced tachycardic and pressor responses was additive. These findings indicate that the cardiovascular effects caused by blockade of GABAergic inhibition in the BLA of the rat are dependent on activation of local NMDA and AMPA receptors. PMID- 9364083 TI - Double dissociation between the involvement of the bed nucleus of the stria terminalis and the central nucleus of the amygdala in startle increases produced by conditioned versus unconditioned fear. AB - The amplitude of the acoustic startle response is reliably enhanced when elicited in the presence of bright light (light-enhanced startle) or in the presence of cues previously paired with shock (fear-potentiated startle). Light-enhanced startle appears to reflect an unconditioned response to an anxiogenic stimulus, whereas fear-potentiated startle reflects a conditioned response to a fear eliciting stimulus. We examine the involvement of the basolateral nucleus of the amygdala, the central nucleus of the amygdala, and the bed nucleus of the stria terminalis in both phenomena. Immediately before light-enhanced or fear potentiated startle testing, rats received intracranial infusions of the AMPA receptor antagonist 2, 3-dihydroxy-6-nitro-7-sulphamoylbenzo(F)-quinoxaline (3 microg) or PBS. Infusions into the central nucleus of the amygdala blocked fear potentiated but not light-enhanced startle, and infusions into the bed nucleus of the stria terminalis blocked light-enhanced but not fear-potentiated startle. Infusions into the basolateral amygdala disrupted both phenomena. These findings indicate that the neuroanatomical substrates of fear-potentiated and light enhanced startle, and perhaps more generally of conditioned and unconditioned fear, may be anatomically dissociated. PMID- 9364084 TI - CaM kinase II and visual input modulate memory formation in the neuronal circuit controlling courtship conditioning. AB - In Drosophila, calcium/calmodulin-dependent protein kinase II (CaM kinase) has been shown to be important in the expression of both learning and memory for the associative behavior courtship conditioning. In this study we examine the role of visual input in producing this behavior and the effects of modifying visual input on CaM kinase-dependent memory formation. Inhibition of CaM kinase blocked apparent learning regardless of visual input. Visual input selectively affected the memory phase of courtship conditioning: normal visual input masked the memory effects of inhibition of CaM kinase resulting in generation of memory without apparent learning, whereas disruption of visual input revealed the CaM kinase dependence of memory. Visual input was found to be important only during the training period, which implies that vision and CaM kinase are interacting in the formation rather than the retrieval of memory. Our results suggest a model for courtship conditioning in which multiple sensory inputs are integrated at a CaM kinase-dependent neuronal switch to modulate courtship behavior. PMID- 9364085 TI - Paradigm busters. PMID- 9364086 TI - A look at Bodies Corporate. AB - One of the most exclusive clubs in the dental world comprises the 27 members who can call themselves Dental Bodies Corporate (DBCs). Among this elite are well known names such as Dental World, Dencare, Whitecross, Benedent and also Oakley, which is owned by Denplan. In the UK only dentists and DBCs are permitted to carry on the business of dentistry. DBCs are simply companies whose directors (the majority of whom must be dentists) are protected by the laws of limited liability, with the purpose of encouraging investment by shareholders (who need not be dentists). This article outlines the story of how this select band of Corporate Bodies gained their exclusive status which goes back to the very earliest days of our profession. PMID- 9364087 TI - How clinical research changed the habit of a lifetime. PMID- 9364088 TI - An unusual case of trauma. PMID- 9364089 TI - An unusual case of trauma. PMID- 9364090 TI - Use of calcium hydroxide for apical barrier formation and healing in non-vital immature permanent teeth: a review. AB - OBJECTIVE: To review the use of calcium hydroxide for induction of apical barrier formation and healing in immature permanent teeth. INTRODUCTION: Pulp necrosis is a frequent complication of dental trauma in immature permanent teeth. Endodontic treatment of these teeth is often complicated. The walls of the root canals are frequently divergent and the apices immature, making debridement and obturation difficult. The aim of treatment is induction of apical healing which may be defined as apical closure through formation of mineralised tissue and repair of the periapical tissues. Calcium hydroxide is the material of choice for apical barrier formation and healing. RESULTS: The use of calcium hydroxide for apical barrier formation is successful in 74-100% of cases irrespective of the proprietary brand used. The average length of time for apical barrier formation is approximately 5 to 20 months. Control of infection and adequate cleaning of the root canal are very important for apical healing. CONCLUSIONS: While the success rate of apical barrier formation using calcium hydroxide is high, long term follow-up of these teeth is necessary. Problems such as failure to control infection, recurrence of infection and cervical root fracture may occur. The latter is more frequent in immature luxated teeth with the least root development. PMID- 9364091 TI - The pattern of splint usage in the management of two common temporomandibular disorders. Part II: The stabilisation splint in the treatment of pain dysfunction syndrome. AB - OBJECTIVE: To examine whether the stabilisation splint is a suitable treatment for pain dysfunction syndrome and to determine the most appropriate pattern of usage. DESIGN: Prospective random control clinical trial. SETTING: Dental school clinic unit. SUBJECTS: 70 patients diagnosed with pain dysfunction syndrome were treated with a stabilisation splint for 3 months. Group 1 (23 patients) wore the splint 24 hours/day. Group 2 (19 patients) wore the splint only during the day. Group 3 (28 patients) wore the splint only at night. RESULTS: There was no statistically significant advantage to any pattern of splint usage; all groups showed a marked improvement by subjective and objective assessment. CONCLUSIONS: Patients being treated for pain dysfunction syndrome by a stabilisation splint need wear the splint only at night. PMID- 9364092 TI - Oral health care in the lives of Gypsy Travellers in east Hertfordshire. AB - OBJECTIVE: To explore Gypsy Travellers' perceptions of dental health and dental service use within the context of culture, environment and the use of other services. SETTING: The author was a community dental officer and the study formed part of a MSc dissertation in dental public health. SUBJECTS AND METHODS: Information was obtained from semi-structured interviews with 43 Gypsy Travellers supplemented by a questionnaire and clinical screening of 72 Travellers. MAIN OUTCOME MEASURES: Place of residence, registration with GMP and GDP, school attendance, caries, normative and perceived barriers to care. RESULTS: The Travellers in the study had a high level of unmet need, low dental registration and very little use of preventive services. Travellers have no cultural barriers to dental care. Control of their travelling was the major factor determining access to education and health services. CONCLUSIONS: There is inequity of dental health and dental service use with more disadvantage being experienced by Travellers on unauthorized and transit sites. PMID- 9364093 TI - Glove selection. PMID- 9364094 TI - Giant cell arteritis--a case report. AB - Giant cell arteritis is a serious condition, requiring immediate treatment. A case illustrating the difficulties of diagnosis is presented, together with a discussion of the management. PMID- 9364095 TI - A matter of minutes--a history of The Hospitals Group 1947-1997. AB - As The Hospitals Group of the BDA reach their 50th anniversary their history has become more than a matter of minutes but spans a considerable number of years of impressive achievements and sheer determination. The following account of the Group's history has been extracted from the minutes of their meetings at the BDA and reflects issues that are still prevalent today. PMID- 9364096 TI - Clusters of meningococcal disease in university students. PMID- 9364098 TI - [The medico-legal examination of death as it should be in Japan]. PMID- 9364097 TI - Sexually transmitted diseases quarterly report: genital Chlamydia trachomatis infection in England and Wales. PMID- 9364100 TI - Evidence suggesting increasing health damage in Scotland related to alcohol. AB - General hospitals in Scotland have experienced a steep rise in discharge rates for alcohol-related diagnoses. This cannot fully be explained by changes in drinking in the general population, a cohort of heavy drinkers, changes in diagnostic practice, or the closure of beds in psychiatric hospitals. Moreover, there has been an increase in deaths from alcoholic liver disease, not easily explained by change in diagnostic practice or a putative cohort of polysubstance abusers with viral hepatitis. Changes in society such as greater income disparity and greater social isolation may contribute and have not been off-set by improvements in availability or outcome of treatment. PMID- 9364099 TI - A case of successfully treated giardiasis in pancreas. AB - We report a case of giardiasis in the pancreas in a patient with diabetes mellitus. The patient is interesting in the following: 1) Giardia lamblia was found only in the pancreas and not in the gall bladder by cytology on endoscopic retrograde cholangiopancreaticography (ERCP) and by cerulein-secretin test (CST). 2) ERCP revealed multiple small cysts scattered throughout the pancreas. 3) Decreased pancreatic exocrine function was recovered by treatment with metronidazole. PMID- 9364101 TI - Laboratory techniques for semen analysis: a Scottish survey. AB - OBJECTIVE: To survey the techniques used by Scottish laboratories to undertake semen analysis in the context of the investigation of infertility. DESIGN: A telephone survey. SETTING/SUBJECTS: Laboratories in Scotland performing semen analysis. RESULTS: Thirty-one laboratories reported performing semen analysis for infertility. There was a lack of consistency in the instructions given to patients in several areas, including the period of abstinence prior to producing the specimen and the delivery of the specimen to the laboratory within an appropriate time after ejaculation. Only 19% of laboratories reported using a positive displacement pipette in the dilution of semen and only 26% used phase contrast microscopy for routine semen analysis. The minimum normal values quoted by laboratories for sperm concentration ranged from 20 x 10(6)/ml to greater than 50 x 10(6)/ml. The normal values quoted for sperm morphology ranged from at least 30% normal forms to at least 88% normal forms. Only 13% of laboratories participated in any form of internal or external quality control for semen analysis. CONCLUSIONS: Semen analysis is fundamental to the clinical work up of the infertile couple but, unlike most other laboratory investigations, it is not a standardised test in Scotland. Factors which are known to influence the results such as the advice given to patients about collecting specimens and the methods and equipment used by technicians vary widely. There is not even a consensus on the normal values quoted. This has implications for clinical decisions based on semen analysis and for future accreditation of laboratories. PMID- 9364103 TI - An audit of in-patients aged 18-65 in acute psychiatric wards who are inappropriately placed three months after admission. AB - OBJECTIVE: To identify acute psychiatric patients considered inappropriately placed three months after admission and expedite a more suitable placement by improving liaison with social work. DESIGN: A survey established the point prevalence of inappropriately placed patients. Changes in usual practice were implemented with the identification of a named social worker for each ward and the introduction of a 'contact sheet' which updated the progress of these patients monthly. A repeat survey one year later assessed the impact of these changes. SETTING: Gartnavel Royal Hospital, Greater Glasgow Community and Mental Health NHS Trust. SUBJECTS: Patients aged 18-65 in the acute psychiatric wards who were resident beyond three months. RESULTS: Use of the contact sheet and improved liaison with a named social worker did not shorten the length of stay of the inappropriately placed patients. Conversely, their mean value for in-patient weeks on the dates surveyed increased from 41.8 in 1994 to 64.7 in 1995. (p = 0.05, 95% confidence intervals from -1 to 42. The length of stay of patients who were still considered to be appropriately placed beyond three months after admission decreased from a mean of 47.7 to 31.9 weeks. (p > 0.5, 95% confidence intervals from -16 to 16). By 1995 the mean length of stay was significantly greater for inappropriately placed patients (p = 0.008, 95% confidence intervals from 10 to 47). CONCLUSIONS: Improved liaison with social work at an operational level was not sufficient to solve the problem of inappropriately placed patients on acute wards. Additional factors such as limited access to rehabilitation placements and patients having complex physical or behavioural problems made placement elsewhere difficult. Such patients with unmet needs place increasing strain on acute psychiatric beds. A reappraisal of current services is required. PMID- 9364102 TI - Does participation in distance learning and audit improve the care of patients with acute asthma attacks? The General Practitioners in Asthma Group. AB - OBJECTIVE: To test whether general practitioners who completed an audit cycle encompassing a data recording exercise, distance learning programme and personalized feedback changed their management of patients with acute asthma attacks. DESIGN, SETTING AND SUBJECTS: Practice and patient details from two national correspondence surveys of the management of acute asthma attacks in the United Kingdom in 1991-92 and 1992-93 were compared. Main outcome measures were use of nebulised bronchodilators, systemic steroids during an asthma attack, and increased use of prophylactic therapy after attacks. RESULTS: Ninety-one general practitioners completed an audit cycle and reported data on 782 patients with asthma attacks in 1991-92 and 669 in 1992-93. There were no significant changes in practice resources during this time. Management changed in line with recommended guidelines and audit feedback suggestions leading to more use of nebulised bronchodilators [272 (35%) before, 268 (40%) after, Odds Ratio (OR) 0.80, 95% Confidence Intervals (CI) 0.64-0.99], systemic steroids [563 (72%) before, 506 (76%) after, OR 0.83, CI 0.65-1.06], and 'step-up' in preventative therapy [402 (51%) before, 382 (57%) after, OR 0.79, CI 0.64-0.98]. CONCLUSION: General Practitioners who completed an audit cycle showed changes in the management of acute asthma attacks in line with guidelines which may have been caused by participation in distance learning and clinical audit. However, general practitioners motivated to change clinical management may be similarly motivated to take part in audit. Audit may be the catalyst for change rather than the cause of change. PMID- 9364105 TI - Beds occupied by emergency patients: long-term trends in patterns of short-term fluctuation in Scotland. PMID- 9364104 TI - Patterns of acute medical receiving in Scotland. AB - The study reviews the patterns of acute medical receiving in Scottish hospitals. Physicians from hospitals with an accident and emergency department and more than 3,000 medical discharges per year were questioned on consultant working behaviour, acute bed usage, the presence of triage and type of geriatric liaison service. The situation as of October 1996 in 26 hospitals is described. In six Trusts consultants have time off other duties to help with acute admissions. In five there is consultant responsibility for acute patients for more than 24 hours, up to a week. Six units have a policy of triage to specialty wards. Eighteen of the 26 units have an Acute Admission Unit (AAU). The needs related geriatric service predominates, but many geriatricians now visit the medical AAU daily. Acute medical receiving systems have been stressed by competing demands and the rise in medical admissions. Most medical units in Scotland have developed new ways of working or are looking at adaptations of their receiving systems. PMID- 9364106 TI - Coping with the inexorable rise in medical admissions: evaluating a radical reorganisation of acute medical care in a Scottish district general hospital. AB - OBJECTIVE: To describe radical changes in acute medical care in a district general hospital and assess their impact on staff and patients. DESIGN: A before and after comparison of structure, process and outcome indicators in the year preceding and following reorganisation. SETTING: The Adult Medicine Clinical Directorate of the Royal Alexandra Hospital in Paisley, Scotland. SUBJECTS: Staff in the Medical Directorate and a random sample of 400 patients. INTERVENTIONS: The main stimulus for reorganisation was the pressure caused by a relatively steep rise in admissions. In response, the six existing general medical wards were converted into a 38-bed Medical Admissions Unit and five more specialised wards. A new acute receiving rota allowed each consultant to concentrate almost exclusively on acute receiving for one week at a time. RESULTS: The boarding of patients in non-medical wards was eliminated through improved bed management. The needs of patients became better matched to the specialism of their consultant. The cardiologist's share of in-patients with cardiological problems rose from 34% of 2,877 cases to 58% of 3,085 cases (p < 0.001) and the respiratory physicians' share of respiratory in-patients grew from 53% of 1,281 cases to 67% of 1,287 cases (p < 0.001). After the reorganisation, medical staff had significantly fewer concerns about losing track of patients (p < 0.01) or about boarding (p < 0.01), however, concern about 'blocked beds' became greater (p < 0.05). Nurses reported more time for health promotion (p < 0.01) but also a rise in stress (p < 0.05). More patients reported that staff had time to explain their treatment (85/109 (79%) before, 93/105 (89%) after, p < 0.05) and a higher proportion felt ready for discharge (91/108 (84%) before, 99/106 (93%) after, p < 0.05). CONCLUSIONS: Radical reorganisation of medical care in response to rising acute medical admissions is achievable and may lead to improvements in care. PMID- 9364107 TI - The Chief Scientist reports... A controlled investigation of changes following a programme of community living, skills training and the validation of these changes through relocation. AB - Fifty-seven adults with mild to moderate learning disabilities served as subjects in a community living skills training project. Twenty-nine subjects were trained using in vivo techniques, 13 were taught using classroom techniques and 15 subjects acted as a no-treatment control group. The effects of the training programme were assessed using videotaped assessments rated by independent observers and the in vivo techniques were found to be significantly superior to the teaching and no-treatment control conditions. These effects were still evident at one year and two year follow-up assessments. Two years after the final follow-up, eventual relocation was examined and the in vivo group were found to have significantly more independent living circumstances than either of the two control groups. PMID- 9364108 TI - Policy-relevant program evaluation in a national substance abuse treatment system. AB - This article discusses recent trends in public and private substance abuse services and offers suggestions on how the evaluation of such services can inform clinical practice and policy making. This analysis focuses particularly on the Department of Veterans Affairs (VA), which operates the largest substance abuse treatment system in the United States. In recent years, there has been an erosion of services for substance abuse outside the VA. In contrast, due to increased funding from the U.S. Congress, the VA significantly expanded substance abuse treatment from 1990 to 1994. However, efforts to "reinvent" and downsize government initiated a reversal of this growth trend in 1994, and VA services may shrink further as the system becomes more decentralized and adopts managed care strategies from the private sector. Drawing from the VA Program Evaluation and Resource Center's (PERC) experience of evaluating the VA system and working with federal policy makers, this article presents examples and suggestions for making evaluations of substance abuse treatment systems more useful in policy discussions and in day-to-day clinical practice. PMID- 9364109 TI - State health care reforms: how they affect children and adolescents with emotional disorders and their families. AB - This article reports on the Health Care Reform Tracking Project, a national study designed to describe and analyze state health care reforms and their impact on children and adolescents with emotional disorders and their families. It summarizes the results of the baseline survey of states conducted in 1995, exploring the nature and extent of the reforms in which states are engaged, most of which involve applying managed care technologies to their Medicaid programs. Trends across states are identified with respect to mental health service delivery, particularly with respect to children and adolescents. The article concludes with a discussion of issues and concerns related not only to mental health service delivery for children and adolescents with emotional disorders and their families but also to the systems of care that have been developing over the past decade to serve them. Some of these concerns include the lack of pilots or demonstrations, limited mental health coverage in some reforms, the lack of integration between mental health and substance abuse systems, the lack of special provisions for children, the need for more reliable bases for deriving capitation rates, the limited incorporation of systems of care, the need to incorporate interagency treatment planning and service delivery approaches, the lack of outcome measures specific to and appropriate for children, and the need for greater family involvement in the planning and implementation of these reforms. PMID- 9364110 TI - The transition to adulthood for youth who have serious emotional disturbance: developmental transition and young adult outcomes. AB - This article reviews studies that depict the developmental transition from adolescence to young adulthood of persons who have experienced serious emotional disturbance (SED) as children or adolescents. The literature demonstrates that their plight in young adulthood is grave. Youth with SED enter the transition phase delayed in their developmental maturation and face additional challenges relative to their nondisabled peers. As a group, they are undereducated, underemployed, and have limited social supports. Homelessness, criminal activity, and drug use are prevalent. This article defines the transitional youth population, describes the developmental tasks of transition, and summarizes the results of longitudinal studies that have tracked functional outcomes of transitional youth into young adulthood. The discussion focuses on the relevance of these findings to service provision. PMID- 9364111 TI - Risk of juvenile justice systems referral among children in a public mental health system. AB - This study established the risk of police referral among a cohort of children who were recipients of public mental health services. Investigators used secondary data to calculate the incidence of criminal referral among 645 children, ages 10 to 17, who entered community-based public mental health programs in King County, Washington. Children receiving public mental health services were nearly three times more likely to be referred to the juvenile justice system compared to children of similar age and gender in the general population. Relative risks were particularly high for younger children (10-13 years) and for children of Hispanic, Native American, and Caucasian origin. Understanding the characteristics and experiences of children who use multiple-service systems has important implications for services delivery. In addressing the needs of youth who have both mental illness and criminal involvement, age- and culturally specific interventions and advocacy efforts are warranted. PMID- 9364112 TI - Risk factors for juvenile justice system referral among children in a public mental health system. AB - The objective of this study is to identify, through the use of secondary data, risk factors for juvenile justice system involvement among children entering a public mental health system. Data-sharing agreements between juvenile justice and mental health systems enabled investigators to examine criminal referrals among 645 children between the ages of 10 to 17 who entered community-based public mental health programs in King County, Washington, over the course of a single year. Univariate and logistic regression analyses were performed. Adjusting for age, gender, and ethnicity, children involved in the public mental health system who had juvenile justice referrals were more likely than children involved in the mental health system without juvenile justice referrals to have parents with a history of incarceration, to abuse drugs and/or alcohol, and to have experienced physical abuse. The study shows that some children who receive public mental health services are at particular risk of having an encounter with the juvenile justice system. Understanding the characteristics and experiences of youth who use multiple service systems has important implications for children's mental health services delivery. PMID- 9364113 TI - Program environments of self-help agencies for persons with mental disabilities. AB - Leaders of self-help agencies (SHAs) aspire to develop program environments that are different from community mental health agencies (CMHAs). This article addresses two questions. Do consumers' perceptions of SHAs approximate the characteristics leaders think ought to typify such agencies? Do SHA and CMHA consumers differ in their program perceptions? Using the Community-Oriented Program Environment Scale, leader expectations of ideal SHA environments were obtained from a national survey of 189 consumer-run agency heads, perceptions of actual environments from interviews with 310 SHA consumers, and perceptions of CMHAs from questionnaire responses of 779 consumers in 54 programs. SHA reality conforms to ideology in offering opportunities for consumers to experience involvement, support, and autonomy in the receipt of needed service. While showing only modest differences from CMHAs on relationship and treatment characteristics, SHA consumers differ in their perceived control over program rules, a fact previously found significant in promoting positive outcomes. PMID- 9364114 TI - Children's mental health in a continuum of care: clinical outcomes at 18 months for the Fort Bragg demonstration. AB - This article uses data collected at 18 months from the evaluation of the continuum of mental health services of the Fort Bragg Child and Adolescent Mental Health Demonstration Project (the Demonstration) to address the hypotheses that longer term follow-up (beyond 12 months) will show that the Demonstration is more effective and more successful for children with serious emotional disturbance (SED). The effects of the Demonstration are examined in comparison to those of traditional care by analyzing 12 key mental health outcomes with a random regression model, and the potential impact of attrition on results is explored. Results show neither hypothesis is supported, and the attrition analysis showed that the influence of missing data on the outcome analyses is negligible. Implications of these results for mental health policy are discussed. PMID- 9364115 TI - Comment on Belcher and DeForge's "The appropriate role for the state hospital system". PMID- 9364116 TI - Comparison of pregnancy outcome between treated and untreated women with chlamydial cervicitis. AB - BACKGROUND: Maternal, fetal, neonatal, and infant outcome in treated versus untreated pregnant women with positive endocervical cultures for Chlamydia trachomatis is controversial. METHODS: One thousand three hundred fifty pregnant women registering consecutively on the staff clinic service were screened for chlamydia. The results of the antigen, but not the culture tests, were available for clinical management. RESULTS: Eighty one patients had positive chlamydia cultures, a prevalence rate of 5.1%. Fifty eight patients were not treated, 44 because of false-negative direct antigen tests. Twenty three patients were treated. Maternal complications including abortion, preterm rupture of membranes, preterm delivery, chorioamnionitis, and endometritis were similar in the two groups. Similarly, neonatal and infant complications including prematurity, conjunctivitis, and pneumonia were similar in the two groups. CONCLUSIONS: Our findings suggest that further prospective, controlled culture based studies are needed before recommending routine screening for chlamydia even in high risk populations. PMID- 9364117 TI - General management of acute poisonings. PMID- 9364118 TI - Coding concepts. PMID- 9364119 TI - Inappropriate use of DEA numbers. PMID- 9364120 TI - Physicians should recommend flu immunization. PMID- 9364121 TI - The urban child's health and environment. PMID- 9364122 TI - The effect of child survival on fertility in Zimbabwe: a micro-macro level analysis. AB - The literature on the effect of fertility on child survival is extensive especially since the accumulation of data from the World Fertility, and Demographic and Health Surveys. Comparatively, empirical studies examining the other side of the relationship--the effect of child survival on fertility--are sparse although theoretical considerations suggest the interdependence of child survival and fertility. Furthermore, the relationship of child survival and fertility is often examined at the micro-level. There is growing recognition, however, that this relationship may be also influenced by macro-level factors. This study attempts to measure the effect of child survival on birth intervals in Zimbabwe using a micro-macro analytical approach based on the individual and community data from the 1988 Zimbabwe Demographic and Health Survey, and the 1989/1990 Zimbabwe Service Availability Survey, respectively. The multivariate analysis showed that there is a replacement effect in the relationship between child survival and fertility independent of individual characteristics of women in Zimbabwe. The analysis also showed that health interventions as measured by coverage and visit by a mobile family planning clinic, and access to a health service have differential impact on fertility in Zimbabwe controlling for the survival status of the previous to the last child and individual characteristics of the women. PMID- 9364123 TI - Further characterization of field strains of rotavirus from Nigeria VP4 genotype P6 most frequently identified among symptomatically infected children. AB - Polymerase chain reaction was utilized to characterize the VP4 types of 39 Rotavirus field isolates from symptomatically infected children in Nigeria. Genotype P6 was identified most frequently, occurring in 41.03 per cent of the typed specimens. Genotype P8 was identified as the next most prevalent (33.3% per cent). Genotype p6 was widespread (68.75 per cent) among infected neonates in Southern Nigeria, but mix infection was more prevalent (70 per cent) among Northern Nigerian children. Four distinct strains were identified with four different P genotypes. Overall strain G1P8 predominated (22.22 per cent) followed by G3P6 (17.8 per cent). Strain G1P8 was most prevalent (70 per cent) among infants aged 3.1-9 months, but strain G3P6 was most frequently identified among neonates < or = 3 months (50 per cent). While strain G1P8 was circulating across the country at this time, strain G3P6 was regionally most identified (77.8 per cent) in Southern Nigeria. The presence of untypeable VP4 gene in Nigeria was demonstrated. The occurance of mix infection genotype demonstrates the potential for reassortment events among different rotavirus genogroups in Nigeria. The epidemiological implications of these findings for rotavirus vaccine development and application in the country were discussed. PMID- 9364124 TI - Transplacental dilution of tetanus antitoxins in Delhi. AB - Maternal blood-cord samples from 171 women of middle socio-economic status who had been administered at least two doses of tetanus toxoid (TT), were assayed for tetanus antitoxins by passive haemagglutination (PHA) test. All the mother as well as cord samples had antitoxin titres > or = 0.015IU/ml, the generally accepted minimal protective level; 98 per cent of the mothers and 97 per cent of the newborns had levels > or = 0.125IU/ml. Transplacental dilution was observed in 45 per cent of the samples; the cord/maternal antitoxin ratio (C/M) of geometric mean titre (GMT) was found to be 0.72. The C/M ratio was not affected by the maternal age, parity, birth weight, and number of TT doses administered to mother. The study showed that tetanus antitoxins were diluted on the fetal side of circulation, but the protective levels of antitoxins were achieved in all the newborns as the mothers had received at least two doses of TT before delivery. PMID- 9364125 TI - Septicaemia in paediatric cancer patients: a 5-year surveillance study in university hospital, Kuala Lumpur, Malaysia. AB - Infectious complications are the major cause of morbidity and mortality in children with malignancy. Empirical antimicrobial therapy in the management of fever of unknown origin should be tailored to local bacteriological data and antibiotic sensitivity patterns. Five-hundred-and-fifty-nine cases of culture proven septicaemia occurring in pediatric cancer patients between 1990 and 1994 were retrospectively analysed and compared with a similar study done in our centre between 1976 and 1979. A wide spectrum of organisms was isolated. Staphylococcus epidermidis, Staphylococcus aureus, and Klebsiella pneumoniae were the most common and consistent bacteria isolated during the 5 year period. More than 70 per cent of the staphylococci were sensitive to methicillin and universally sensitive to vancomycin. However, a worrying trend of ceftazidime resistance amongst gram-negative organisms was found. In these situations, the use of imipenem is recommended as resistance to this antimicrobial agent was exceedingly rare. PMID- 9364126 TI - Cryptosporidium infection in children in urban Bangladesh. AB - We reviewed data during 1991-94 from a systematic 4 per cent subsample of all patients who presented with diarrhoea to our facility, in which there were 1949 cases of acute diarrhoea in children between the ages of birth to 59 months. Cryptosporidia oocysts were detected in the stools of 68 (3.5 per cent) of these children. A case-control study was designed using surveillance data which included the 68 children with stool positive for Cryptosporidium as cases. Two hundred and four children who did not have Cryptosporidium were randomly selected to serve as controls. The most common presentations were watery diarrhoea (91 per cent), dehydration (81 per cent), and vomiting (71 per cent), and Cryptosporidium was detected throughout the year, but was most frequently isolated during April to October. Lowest rates of detection were observed in the months of November, December, and January. Age below 2 years, non-breastfeeding, and stunting were significantly associated with Cryptosporidium infection. In multivariate analysis of our study we found that only stunted (P = 0.031) and non-breastfed children (P = 0.022) had a greater risk of having Cryptosporidium infection. PMID- 9364127 TI - Breastfeeding at 6 weeks and predictive factors. AB - Despite the numerous changes made in accordance with the Baby Friendly Hospital Initiative at the University Hospital, Kuala Lumpur, the low rates of breastfeeding have persisted. This study aims to examine the current trend in infant feeding, and the influences of some perinatal and sociodemographic factors on breastfeeding. Five-hundred mothers with singleton pregnancies and healthy infants were interviewed at 6 weeks post-partum. Only 124 (25 per cent) mothers were practising exclusive breastfeeding (EBF), and 132 (26 per cent) mothers were using exclusive infant formula feeding (EIF). On logistic regression analyses, mothers who followed EBF were more likely to have had antenatal plans to breastfeed (Odds ratio 2.44, 95 per cent confidence interval 1.75-3.45), not in paid employment post-natally (OR 1.76, 95 per cent CI 1.31-2.36), of older age group (> 27 years) (OR 1.48, 95 per cent CI 1.13-1.93), had female infants (OR 1.38, 95 per cent CI 1.05-1.80) and of Indian ethnicity (compared to Chinese) (OR 3.87, 95 per cent CI 2.16-6.89). Breastfeeding difficulties were associated with decreased odds of EBF (OR 0.21, 95 per cent CI 0.13-0.34). Parental education, fathers' ages and incomes, primigravida status, Caesarean section, present of episiotomy, late first breastfeed, phototherapy, and length of hospital stay were not significant predictors of failure of EBF. In comparison, predictive factors for increased use of EIF were mothers who have had breastfeeding difficulties, < or = 9 years of schooling, and of Chinese descent. In conclusions, the overall rate of EBF by 6 weeks of age in infants born in this urban hospital had remained poor. The adverse factors for EBF identified in this study warrant further in depth studies to determine effective ways of improving EBF rates. PMID- 9364128 TI - Long-term prospects of malnourished children after rehabilitation at the Nutrition Rehabilitation Centre of St Mary's Hospital, Mumias, Kenya. AB - The growth and survival of children was studied after rehabilitation for malnutrition at the Nutrition Rehabilitation Centre (NRC) of St Mary's Hospital on average 1.5 year after discharge. The findings are intended partly to provide descriptive information on later progress in the community of these children and also to identify specific risk factors. Of 50 children eligible for follow-up, 39 (78 per cent) could be traced. Overall mortality was 36 per cent, 28 per cent were found to be underweight, and 36 per cent were in good condition with satisfactory catch up in weight. Mortality was determined by age, duration of stay in hospital and centre, and nutritional status. Most literature on the subject implies that the long-term effectiveness of the NRC is affected by limiting factors at home and in the centre itself. Our data suggest that the poor results are mainly due to improper use of the NRC. The NRC was called in too early by the hospital and children were discharged too soon from the NRC. As evidenced by the frequent presence of infectious symptoms, the severity of nutritional status, inadequate weight gain, and short duration of stay in the hospital and the NRC. PMID- 9364129 TI - Heights and weights of primary school children of different social background in Ankara, Turkey. AB - A cross-sectional anthropometric survey was carried out in a low socio-economic and high socio-economic region of Ankara, Turkey, to measure the weights and heights of school children. The study group consisted of 5289 children between the ages of 5 and 11 years. Both boys and girls from the high socio-economic group had superior body measurements compared to those of the low socio-economic group. The difference between the mean weight for age values of two groups was statistically significant (P < 0.05), whereas no statistically significant difference was found on the basis of height for age values among all age groups. To make a comparison both with National Centre for Health Statistics and World Health Organisation (NCHS-WHO) standards and Turkish standards we used the data from high socio-economic group only. Our results showed that the mean height and weight values of boys and girls were higher than the 50th centile height and weight values of NCHS-WHO standards. Almost 25 years have passed since the measurements of Turkish standards were taken. The height differences were in the range of 0.24-1.51 cm/decade, with a mean value of 0.96 cm/ decade. These results led us to conclude that, local/regional standards for height and weight are needed, and repeated assessments are useful for follow-up of populations. PMID- 9364130 TI - Breastfeeding and supplemental feeding for neonates in Al-Ain, United Arab Emirates. AB - A prospective cohort study was carried out to determine the factors affecting initiation of breastfeeding, and describe patterns of breastfeeding and supplemental feeding in the multiethnically and culturally diverse population of Al Ain, UAE. Two-hundred-and-twenty-one infants completed the 4 weeks of follow up. None of the mothers opted not to breastfeed, but only 4 per cent of them practiced exclusive breastfeeding during the first month of the infants' life; 51 per cent of them initiated breastfeeding on the first day of life. Factors associated with delayed initiation of breastfeeding beyond the first day of life included low birth weight, complicated delivery, ignorance of the advantages of colostrum, and young maternal age. Non-milk supplements fed to babies included water, tea, juice, yansun, and babunj (local herbal drinks). The preferred method of feeding the supplements was the feeding bottle. There were significant associations between the use of these supplements and the mother's nationality and education. PMID- 9364131 TI - Evaluation of Teknaf Enteric Agar (TEA): A modified MacConkey's Agar for the isolation of Shigella dysenteriae type 1 and Shigella flexneri. AB - To develop a better and selective medium for the isolation of Shigella spp., MacConkey's Agar (MAC) was modified by adding potassium tellurite (K2TeO3) at a concentration of 1 microgram/ml. The formulation designated Teknaf Enteric Agar (TEA) was studied for the inhibitory effect of potassium tellurite on the growth of different enteric bacteria, and as a medium for isolating Shigella spp. from clinical stool samples (n = 3125). We observed that the growth of E. coli was effectively inhibited on TEA with no effect on the growth of S. dysenteriae type 1 and S. flexneri. A total of 2019 Shigellae were isolated through the combined use of TEA, MAC, and Salmonella-Shigella Agar (SS). On TEA, 1921 S. dysenteriae type 1 and S. flexneri were isolated as compared to 1765 from the combined use of MAC and SS. A total of 194 of S. dysenteriae type 1 and S. flexneri were exclusively isolated from TEA as compared to 38 which were only made from MAC and SS. We conclude that TEA significantly increased the overall isolation rate of Shigella spp. as compared to the combined use of MAC and SS (P < 0.0001), although it is not suitable for the isolation of S. sonnei. PMID- 9364132 TI - Peripheral gangrene in children at the Jos University Teaching Hospital. PMID- 9364133 TI - The utility of using a distended abdomen to predict intestinal parasites in asymptomatic children. PMID- 9364134 TI - Alcaptonuria in a Turkish baby. PMID- 9364135 TI - The influenza conundrum. PMID- 9364136 TI - The current status of acellular pertussis vaccines. PMID- 9364137 TI - Production and characterisation of monoclonal antibodies to heat-shock protein 60 of Helicobacter pylori. AB - Two monoclonal antibodies (MAbs), designated as H9 (IgG2a) and H20 (IgM), directed against heat-shock protein 60 (HSP60) of Helicobacter pylori strain TK1029 were established. Affinity-purified antigens cross-reacted in immunoblots with MAb H9 and MAb H20 respectively. These antigens also reacted with the 3C8 MAb previously established in this laboratory, which recognised Yersinia enterocolitica HSP60. By amino-acid sequence analysis, the N-terminal amino-acid sequence of the protein recognised by both H9 and H20 MAbs was confirmed as the amino-acid sequence of H. pylori HSP60 reported previously. Both MAbs reacted with nine strains of H. pylori in enzyme-linked immunosorbent assay (ELISA) and immunoblot analysis. In addition, MAb H9 reacted with extracts of other bacteria including H. mustelae, Pseudomonas aeruginosa, Vibrio cholerae, Serratia marcescens, Proteus mirabilis, Escherichia coli and Shigella sonnei. In contrast, MAb H20 reacted only with strains H. pylori. These results suggest that both the species-specific epitope recognised by MAb H20 and the common epitope recognised by MAb H9 exist on HSP60 of the bacterial cell. Both MAbs also reacted with the 60-kDa protein in the lysate of human gastric carcinoma (MKN45) cells. It was shown by immunohistochemical staining that gastric epithelial cells of four out of six biopsy specimens examined stained positively with MAb H20. These results suggest that there is a common epitope in H. pylori HSP60 and human gastric epithelial cells. PMID- 9364138 TI - Heat-shock protein 60 homologue of Helicobacter pylori is associated with adhesion of H. pylori to human gastric epithelial cells. AB - A previous study reported a relationship between the expression of heat-shock protein 60 (HSP60) by Helicobacter pylori and its adhesion to human gastric carcinoma (MKN45) cells. To examine whether the HSP60 homologue of H. pylori is associated with the adhesion of H. pylori to human gastric epithelial cells, an inhibition assay of adhesion of H. pylori to MKN45 cells was performed by flow cytometric analysis with monoclonal antibody (MAb) designated as H20 recognising HSP60 of H. pylori. The rate of adhesion of H. pylori pretreated with MAbH20 to MKN45 cells was lower than that of untreated H. pylori. Primary human gastric epithelial cells from a patient with gastric cancer were also prepared for comparison in the inhibition assay with MAbH20. H. pylori adhered to the primary human gastric epithelial cells, and this adhesion was significantly inhibited by MAbH20. These results suggest that the H. pylori HSP60 homologue recognised by MAbH20 might be associated with the adhesion of H. pylori to primary human gastric epithelial cells as well as to cultured gastric cancer cells. PMID- 9364139 TI - Influence of iron, growth temperature and plasmids on siderophore production in Aeromonas hydrophila. AB - Aeromonas hydrophila strains obtained from diarrhoeal samples of human patients (19 isolates) and freshwater ponds (11 isolates) were analysed for siderophore production. Both clinical and environmental isolates showed significantly increased siderophore production under iron-limiting conditions both at 28 degrees C and at 37 degrees C. Clinical isolates consistently produced higher levels of siderophores than did the environmental isolates. The role of plasmids in moderating siderophore production was studied after curing with acridine orange. Treatment with acridine orange for 24 h removed the larger plasmids but the smaller plasmids (< 5 MDa), more common in the environmental isolates, were resistant to curing. As found in the untreated isolates, the cured clinical isolates produced higher mean levels of siderophores than the cured environmental isolates. Siderophore production in A. hydrophila was significantly influenced by iron-limiting cultural conditions and the source of isolates, but plasmid content and growth temperature at 28 degrees C or 37 degrees C had little effect on production. The basis for the greater production of siderophores in clinical isolates than in environmental isolates needs further study. PMID- 9364140 TI - Rickettsia rickettsii growth and temperature-inducible protein expression in embryonic tick cell lines. AB - Rickettsia rickettsii has limited adverse effects on its arthropod vector, but causes severe disease in man. To model differences in host-parasite interaction, R. rickettsii growth and protein expression were examined at temperatures reflective of host environment in the tick cell lines DALBE3 and IDE2, the human endothelial cell line ECV304, and the African green monkey kidney cell line Vero76. At low multiplicities of infection, rickettsial titres increased 10(2) 10(3)-fold in all cell lines after incubation for 3 days at 34 degrees C. At higher multiplicities and with extended incubation, R. rickettsii showed enhanced survival in tick versus mammalian cells. No difference in rickettsial ultrastructure or protein profiles was detected between different host cell types. Rickettsial proteins of 42, 43, 48, 75 and 100 kDa are induced in tick cells shifted from 28 degrees to 34 degrees C, but not in cells maintained at 28 degrees C. This temperature response may be associated with expression of rickettsial determinants that are pathogenic to mammalian hosts. PMID- 9364142 TI - Evaluation of human hydatid disease before and after surgery and chemotherapy by demonstration of hydatid antigens and antibodies in serum. AB - This study was performed to differentiate serologically between patients with hydatid disease which is active, and which has been successfully cured. A total of 18 cases was included. Pre-treatment serum samples were collected before surgery or chemotherapy. Post-treatment serum samples were collected at various intervals (3 days, 7 days, 1 month, 6 months, 1 year and 2 years) after surgery or chemotherapy. These sera were tested for the presence of circulating hydatid antigen (CAg) by bacterial co-agglutination (Co-A) and counter-current immunoelectrophoresis (CIEP) tests, and for circulating hydatid antibodies (CAb) by indirect haemagglutination assay (IHA). Ten and eight sera, respectively, were positive out of 11 pre-operative and pre-chemotherapeutic sera tested for CAg by the Co-A and CIEP tests. Post-operative sera collected from these cases did not show any CAg by the CIEP test. However, CAg was detected by Co-A in three and four serum samples collected on the third and seventh day, respectively, after surgical removal of the cyst. However, the CAg levels in these post-operative sera showed a gradual decline by the seventh day and were completely absent in the serum specimens collected 1 month after surgery and 6 months after chemotherapy. All the post-operative serum samples except two, collected 2 years after surgical removal of the cyst, in seven cases of old hydatid disease, were negative for CAg by both the CIEP and Co-A tests. Unlike the CAg profile, no marked differences were noted between the CAb profile of the pre- and post treatment sera, as shown by the IHA test. Even 1 year after surgery or chemotherapy, two sera showed a marginal decrease in their CAb titre. CAb at varying titres was still detectable in all seven serum samples from old cases of hydatid disease, even 2 years after surgical removal of the cyst. This study shows the value of serial pre- and post-operative or chemotherapy estimation of CAg by Co-A and CIEP as an index of cure or of continuing hydatid infection. PMID- 9364141 TI - Genome and MIC stability in Mycobacterium tuberculosis and indications for continuation of use of isoniazid in multidrug-resistant tuberculosis. AB - Mycobacterium tuberculosis strains resistant to two or more of the first line antituberculosis drugs (MDR) are a serious threat to successful tuberculosis control programmes. For this retrospective study, 85 follow-up drug resistant isolates from 23 patients residing in a community with a high incidence of tuberculosis were collected and the level of in-vitro resistance to antibiotics determined quantitatively. PCR-SSCP and sequencing techniques were used to screen for gene mutations associated with resistance in 31 follow-up samples from a smaller group of eight patients. DNA fingerprint analysis was done on sequential isolates to confirm identity. Although treatment had a profound effect on changes in drug resistance patterns, the MIC for a particular agent remained constant in follow-up isolates. DNA fingerprinting and mutational analysis (14 different loci) showed that the genome of MDR strains of M. tuberculosis is relatively stable during the course of therapy. The rpoB gene was the most frequently mutated structural gene involved in drug resistance and a novel C to T mutation upstream of open reading frame (ORF)1 of the inhA operon was detected. No evidence was found of the presence of strain W (New York) in this group of MDR strains. The results stress the importance of confirming individuality of strains for the accurate calculation of frequencies of particular mutations associated with drug resistance, particularly in a high incidence area. Approximately one half (47.8%) of the patients had isolates resistant to concentrations just above the critical concentration for isoniazid (MICs of 0.2-5 mg/L). Therefore, these patients and their contacts who develop primary drug-resistant tuberculosis may respond to higher dosages of treatment which could have a considerable impact on the cost and the ease of management of resistant tuberculosis. PMID- 9364143 TI - A comparative study of Fusobacterium necrophorum strains from human and animal sources by phenotypic reactions, pyrolysis mass spectrometry and SDS-PAGE. AB - Fusobacterium necrophorum strains from human infection (21) were compared with strains from animals (17 biotype A, 2 biotype AB, 4 biotype B, 1 biotype unknown), and the type strain NCTC 10575 in conventional tests reaction patterns (CTRPs), SDS-PAGE and pyrolysis mass spectrometry (PMS). Classifications from the three approaches showed one major consensus group comprising all human strains, and another comprising animal biotype A strains. Animal biotype B strains and one animal strain, designated with some doubt to biotype A, were outliers of the consensus 'human strain' group. Again, animal biotype AB strains were outliers of the consensus 'animal biotype A group', as was the type strain, which was clearly atypical in conventional tests and PMS. Colonial and microscopic characters showed good discrimination between the major consensus groups. However, only haemagglutination and the API-ZYM leucine arylamidase of the biochemical tests discriminated well between these groups. The 'animal biotype A group' clearly corresponds to F. necrophorum subsp. necrophorum, but synonymy of F. necrophorum subsp. funduliforme with the group of human strains was less certain. The latter subspecies was described solely on the basis of animal strains, all of biotype B, but each of four animal biotype B strains in this study was an outlier of the 'human strain group' in one or more of the characterisation approaches. Strains of F. necrophorum causing human infection were clearly distinct from the biotype A strains commonly found in animal infection. This has implications for the validity of animal models of human necrobacillosis. In view of these differences, it would be useful to have a validated designation for strains causing human infection. However, it would be premature to assume that the definition of F. necrophorum subsp. funduliforme encompasses the human strains in the absence of confirmatory DNA-homology and 16S rRNA-sequencing studies. PMID- 9364144 TI - Phenotypic characteristics and lipopolysaccharides of human and animal isolates of Fusobacterium necrophorum. AB - As part of a collaborative study, six culture collection isolates and 50 coded isolates of Fusobacterium necrophorum were examined for the types of lipopolysaccharides (LPS) they contained, and to see if this related to their reactions in a range of phenotypic tests and their susceptibility to a panel of six antimicrobial compounds. The biotype B type strain, putative biotype B isolates and human isolates were predominantly coccobacillary, had rough type LPS and some of these isolates (8 of 26) required incubation for > 2 days to demonstrate lipase activity. The biotype A type strain, putative biotype AB isolates and most putative biotype A isolates (16 of 18) were predominantly rod shaped, had either smooth LPS or low M(r) rough type LPS and all demonstrated lipase activity within 2 days. The other two putative biotype A isolates were coccobacillary and had rough type LPS, and one of these required incubation for > 2 days to demonstrate lipase activity. The results of these latter two isolates more closely resembled biotype B. A few isolates were asaccharolytic, but most fermented one or more of glucose, fructose, maltose and galactose. There was no correlation between fermentation pattern and LPS type, biotype or source of isolate (animal or human) but, with the exception of two abberant isolates, there was good correlation between cellular morphology, type of growth in liquid media and LPS type. PMID- 9364145 TI - Classification of human and animal strains of Fusobacterium necrophorum by their pathogenic effects in mice. AB - Forty-six strains of Fusobacterium necrophorum, 24 from animals and 22 of human origin, were examined by pathogenicity tests in mice, while the same strains were being examined in laboratories elsewhere by other methods. The pathogenicity tests consisted of (1) subcutaneous inoculation with a large dose of a pure culture, (2) subcutaneous inoculation with a small dose of F. necrophorum mixed with a large but relatively harmless dose of Staphylococcus aureus, and (3) intravenous inoculation with a large dose of a pure culture. Fourteen strains, all of animal origin, showed the characteristic behaviour of biotype A. Twenty eight strains, 10 of animal origin and 18 from man, were classified as biotype B. The remaining four strains, all from man, produced a distinct type of infection in mice; these strains were referred to as 'A2433-like' because of their resemblance to a strain described in an earlier study. It would appear that biotype A strains, responsible for classical necrobacillosis in animals, do not infect man; that biotype B strains occur in both man and animals; and that 'A2433 like' strains are probably confined to man. PMID- 9364146 TI - Cefsulodin chocolate blood agar: a selective medium for the recovery of Haemophilus influenzae from the respiratory secretions of patients with cystic fibrosis. AB - A modified chocolate blood agar medium incorporating cefsulodin, a semi-synthetic cephalosporin, was developed and compared with non-selective chocolate blood agar and selective haemin-bacitracin blood agar for the routine isolation of Haemophilus influenzae from the respiratory secretions of patients with cystic fibrosis. The results showed that cefsulodin chocolate blood agar improved the recovery rate of H. influenzae in this group of patients. The medium was stable on storage for 10 days at 4 degrees C. PMID- 9364147 TI - A novel mechanism of antibiotic resistance in plague. PMID- 9364148 TI - Application of pulsed-field gel electrophoresis in an outbreak of infection due to Klebsiella oxytoca. PMID- 9364149 TI - Diagnosis of ventilator-associated pneumonia. PMID- 9364150 TI - Making the health care system work better for older people. PMID- 9364151 TI - Hip fractures and osteoporosis in men. PMID- 9364153 TI - Preventing falls by dealing with the causes. PMID- 9364152 TI - Driving and dementia: balancing personal independence and public safety. PMID- 9364154 TI - Positive ageing: facts and opportunities. PMID- 9364156 TI - Urinary incontinence in elderly patients with acute stroke and hip fracture. PMID- 9364155 TI - Hip fracture in elderly men: prognostic factors and outcomes. AB - OBJECTIVE: To examine prognostic factors and outcomes after hip fracture in men aged 60 years and older. DESIGN AND SETTING: Cohort study of all men presenting to St George Hospital (a 650-bed tertiary care centre) with hip fractures in 1995, recruited retrospectively from medical records and evaluated prospectively at six and 12 months after fracture. PATIENTS: 51 men aged 60 years or more (and, for comparison, 51 age-matched women) who presented with hip fracture not caused by high impact injuries or local bone disease. MAIN OUTCOME MEASURES: Prognostic factors (such as pre-existing illness and osteoporotic risk factors) and outcome data (such as fracture-related complications, mortality, and level of function as measured by the Barthel index of activities of daily living at six and 12 months postfracture). RESULTS: Median age of the 51 men was 80 years (interquartile range, 74-86 years); four were aged under 70 years. Outcome assessment was possible for 41 men (80%). Similar proportions of men and women came from institutions (32% v. 28%), and similar additional proportions required institutionalisation after discharge (18% v. 14%). Fracture-related complications affected similar proportions of men and women (30% v. 32%), and mean length of hospital stay was similar. Fourteen per cent of men died in hospital compared with only 6% of women (P = 0.06). Men had more risk factors for osteoporosis (P < 0.01). Physical functioning (measured by the Barthel index) deteriorated significantly in men from 14.9 at baseline to 13.4 at six months (P < 0.05) and 12.4 at 12 months (P < 0.05) after fracture. CONCLUSION: Compared with women, elderly men presenting with hip fracture have higher mortality and have more risk factors for osteoporosis. Like women with hip fracture, men are usually fragile, with pre-existing medical illness and fracture-related complications contributing to their overall poor outcomes. PMID- 9364157 TI - Visual impairment and depression in residential care. PMID- 9364158 TI - Community follow-up for patients discharged from an acute psychiatry unit. PMID- 9364159 TI - Use of inpatient hospital services by people aged 90-99 years. AB - OBJECTIVE: To examine the use of inpatient hospital services by people aged 90-99 years. DESIGN: Retrospective case note review. SETTING: Flinders Medical Centre, a 516-bed university teaching hospital in Adelaide, South Australia. PATIENTS: All patients aged 90-99 years on the separation register for 1995. MAIN OUTCOME MEASURES: Patient demographic characteristics, principal diagnosis, length of hospital stay and outcome, including destination at discharge. RESULTS: In 1995, 317 separations involved 214 patients aged 90-99 years; 148 patients (69%) were admitted to hospital once, 43 (20%) twice and 23 (11%) three times or more. In 54% of separations, patients came from the community, and these were less likely to be emergency admissions (72%) than were admissions from hostels (87%) and nursing homes (93%). Patients had a wide range of acute medical and surgical problems and a median of five documented comorbidities. Patients survived to leave hospital in 290 separations (91%) and returned directly to their previous living circumstances in 212 (67%). Median hospital stay was 5.0 days, and in 25% of separations stay was one day or less. Patients admitted under the care of geriatricians had more emergency admissions (98%) and longer mean hospital stays (8.9 days) than those admitted under surgeons (69%; 5.9 days) or other physicians (66%; 5.0 days). CONCLUSION: Despite the acute nature of their illnesses and their multiple medical problems, most hospitalised nonagenarians in this study returned directly to their previous living circumstances after short hospital stays. PMID- 9364160 TI - Acopia--a new DRG? PMID- 9364161 TI - Health promotion and older people: a qualitative study of general practitioners' views. AB - OBJECTIVES: To explore general practitioners' (GPs') beliefs about health promotion for older people and attitudes towards educational strategies likely to improve practice in this area. DESIGN AND SETTING: Four discussion groups, each lasting one and a half hours, completed in Melbourne, Australia in August and September 1995. Interviews were transcribed verbatim and analysed for major themes. PARTICIPANTS: A convenience sample of 20 GPs took part; 11 university affiliates, four participant contacts and five GPs from telephone book listings. RESULTS: GPs' perceptions of their health promotion practice varied from "integrated into all medical care", to "something separate from usual practice". Positive views of older people contrasted with ageist views, with a few GPs expressing a nihilistic approach to medical care of older people. Regardless of the GPs' attitudes, lack of time and reimbursement disincentives were perceived to limit preventive practice and the potential impact of health promotion interventions. GPs felt overwhelmed with their workloads, and initial reactions to the idea of any "new" program were negative. Reactions to educational strategies varied, with choice and relevance to ease of practice being important for GP participation. CONCLUSIONS: GPs differ in their views of health promotion and in their approaches to its delivery for older people. Educational programs are often viewed negatively, but if they offer the opportunity to save time, increased participation may be more likely. PMID- 9364162 TI - Neurodegenerative and other chronic disorders among people aged 75 years and over in the community. AB - OBJECTIVES: To assess age-related disease patterns in the older population in the community, especially the prevalence of neurodegenerative disorders and their association with systemic and vascular diseases. DESIGN: Cross-sectional, community-based study. SETTING: Area served by the Central Sydney Area Health Service, August 1991 to March 1994. SUBJECTS: 647 people aged 75 years or over, living in the community; 537 (83%) underwent medical assessment. OUTCOME MEASURES: Clinician diagnoses of chronic disease, including neurodegenerative disorders (cognitive and visual impairment, gait ataxia and slowing, dementia and Parkinson's disease); arteriopathy score; age-related trends; and correlations among diagnoses and arteriopathy score. RESULTS: Subjects had mean age of 81.0 years (range, 75-97). The most common diagnosis was arthritis (women, 73%; men, 68%), while the most common neurodegenerative diagnoses were gait ataxia (women, 57%; men, 42%), visual impairment (women, 40%; men, 45%) and cognitive impairment (women, 39%; men, 36%). Neurodegenerative diagnoses increased significantly in prevalence with increasing age, while most systemic diseases tended to decrease, although not significantly. Dementia was diagnosed in 92 subjects (17%), with Alzheimer's disease being the most common cause, but many having multiple causes. Significant correlations were found between neurodegenerative diagnoses and between the arteriopathy score and stroke, but not neurodegenerative diagnoses. CONCLUSIONS: The increase in comorbidities in the older population arises from an age-related increase in neurodegenerative disorders. These form a cluster suggesting a common aetiologic process which is not arteriopathic. PMID- 9364163 TI - Validation of an automated up-timer for measurement of mobility in older adults. AB - OBJECTIVE: To test the reliability, validity and utility of an "up-timer", an automated device to measure time spent standing and walking. DESIGN: Repeat measurement of mobility one week apart in a convenience sample. SETTING: Hostel and nursing homes in Melbourne. PARTICIPANTS: 26 hostel and 24 nursing home residents (aged 70-99 years) participated. They were mobile, with or without the use of walking aids or personal assistance. OUTCOME MEASURES: "Up-time" (measured with the up-timer); functional activity (measured with the Barthel Index, Functional Independence Measure, Timed Up & Go, and Human Activity Profile); and disability (measured by the Rapid Disability Rating Scale). RESULTS: The test retest reliability of the up-timer was high (Pearson's r = 0.84; P < 0.001). Pearson's correlation between the up-timer results and results of functional and disability measures ranged from r = 0.47 to r = 0.55. The functional measures correlated more highly among themselves (r = 0.79 to r = 0.92). The performance based Timed Up & Go test had moderate levels of correlation with both the up timer and the functional measures. Use of the device was well accepted by both participants and staff. CONCLUSIONS: The up-timer is a practical, objective and reliable means of measuring mobility. The useful information it provides is different from, but overlaps with, that obtained from subjective observation or self report. It will complement existing subjective and performance-based measures of activity and mobility. PMID- 9364164 TI - Recruitment strategies for randomised clinical trials in elderly Australians. PMID- 9364166 TI - Recruiting older people for clinical trials and health promotion programs. PMID- 9364165 TI - Recruiting older people to a home safety program. PMID- 9364168 TI - Drugs for the prevention and treatment of Alzheimer's disease. AB - Alzheimer's disease affects up to 100,000 people in Australia, but pharmacological treatment has only been available in recent years. Currently available drugs provide modest relief of symptoms for varying periods of time but have no proven preventive action against the disease. PMID- 9364167 TI - Alzheimer's disease: risk and protection. AB - Only four risk factors for Alzheimer's disease can be regarded as confirmed--old age, family history of dementia, apo-E genotype and Down syndrome. Other disputed risk factors with some supporting evidence include ethnic group, head trauma and aluminium in drinking water. Possible protection factors, such as anti inflammatory drugs, oestrogen replacement therapy and a high education level, are of great interest because they suggest possible preventive action. PMID- 9364169 TI - Driving and dementia: a cause for concern. PMID- 9364170 TI - The Resident Classification Scale. PMID- 9364171 TI - GPs and geriatricians working together. PMID- 9364172 TI - Undernutrition in older hospitalised patients. PMID- 9364173 TI - Influenza vaccination among the elderly in South Australia. PMID- 9364174 TI - p53: from clinical significance to significance in the clinic? PMID- 9364175 TI - An audit of the assessment and management of adults admitted to Christchurch Hospital with community acquired pneumonia. AB - AIMS: To audit the management of adult patients admitted with community acquired pneumonia including the standards of clinical assessment, use of modified British Thoracic Society prognostic criteria and antibiotic therapy. METHODS: A prospective, 16 week, study of consecutive patients admitted to Christchurch Hospital with community acquired pneumonia. RESULTS: Ninety-six patients met the inclusion criteria. The median age was 70 years. A pathogen was identified in 28 (26%) patients. Forty two patients fulfilled the modified British Thoracic Society criteria for severe disease and all 9 deaths occurred in that subgroup. The management guidelines were followed without exception in only 15% of cases. Documentation of the prognostic criteria was often incomplete and therefore only 33% of those patients with severe disease were correctly identified. Seventy one percent of those with severe disease were treated with only one antibiotic and there was significant delay in administering the first dose in 44% of cases. A follow up chest radiograph was performed in 43 (51%) of those discharged. CONCLUSIONS: There was poor compliance with the management guidelines. There was a lack of awareness of the severity criteria leading to inadequate treatment in many cases. Further educational initiatives are indicated. PMID- 9364176 TI - Tuberculosis in those with HIV infection. AB - AIMS: To determine the incidence, demography, clinical features, treatments and outcome for patients with tuberculosis and human immunodeficiency virus (HIV) infection in Auckland. METHODS: We reviewed the notes of all patients with HIV infection and tuberculosis seen by the Infectious Disease Unit, at Auckland Hospital since the onset of the HIV epidemic in New Zealand in 1984 until 31 December 1995. RESULTS: Eleven patients have had HIV infection and tuberculosis, 2.4% of all those with HIV infection cared for by this unit. Ten were male and eight homosexual. The median age was 30 years (range 24-57). The incidence in Pakeha was 1.2% (3 of 234), in Maori 20% (5 of 25) and in African 27% (3 of 11). Until 1990 we saw one case every two years and since then one or two cases per year. Six patients had normal chest x-rays and five had abnormal chest x-rays; of the latter, three were typical of tuberculosis and two atypical. Ten of the eleven strains of Mycobacterium tuberculosis cultured were fully sensitive but one was resistant to both rifampicin and isoniazid. Conventional treatment regimens were used. Seven patients have died of HIV infection, three continue treatment and one returned to Africa. One patient relapsed with fully sensitive tuberculosis. Three patients had major side effects to rifampicin necessitating alternative treatment. CONCLUSIONS: Tuberculosis is uncommon amongst those with HIV infection in Auckland but the incidence has risen in recent years. The risks amongst Maori and Africans are high. Multidrug resistant tuberculosis is uncommon. Those caring for patients with tuberculosis need to be mindful of HIV infection: those caring for patients with HIV infection need to be increasingly alert for tuberculosis. PMID- 9364177 TI - Acute gastroenteritis diagnostic practices of New Zealand general practitioners. AB - AIMS: A sample of New Zealand general practitioners was surveyed to determine the laboratory referral practices of general practitioners for patients with acute gastroenteritis, with particular reference to viral gastroenteritis. METHODS: A mail questionnaire was sent to 209 general practitioners throughout New Zealand. RESULTS: The most important criteria for laboratory referral of a diarrhoeal specimen were prolonged duration of illness, presence of blood in the stool, a recent history of overseas travel, tramping or camping, shellfish consumption, or if the patient worked in the food, child care, or health care industries. Most general practitioners reported that they would refer diarrhoeal specimens from less than 25% of their patients with acute gastroenteritis. Requests for testing for viruses other than rotavirus were rare. CONCLUSION: The viral agents causing acute gastroenteritis were less likely to receive laboratory confirmation than other causes of gastroenteritis. On the basis of current laboratory investigation practices of general practitioners, foodborne viral gastroenteritis outbreaks are unlikely to be identified as such in New Zealand. PMID- 9364178 TI - A trial of two methods of taking cervical smears: the Aylesbury spatula plus cytology brush compared to the Cervex broom. AB - AIMS: To compare the adequacy of cervical smear taking, using the Aylesbury spatula plus cytology brush with the Cervex broom. METHODS: Two cervical smears were taken at the same visit, the women acting as their own controls. In Group 1 comprising 81 women, the first smear was taken using the Cervex broom. In Group 2 comprising 97 women, the first smear was taken using the Aylesbury spatula followed by the cytology brush. The tips of the samplers were sent to the laboratory in a cytology container with 30% ethyl alcohol in saline, for analysis of residual cells. RESULTS: It took experienced staff two or three smears before they were adept at taking an adequate Cervex broom sample as defined by the presence of endocervical cells. Both techniques were equally good at detecting significant abnormalities. When the Cervex broom was used first there were more smears with no blood present but when bleeding occurred there was no significant difference between the two groups. Both techniques were well accepted by the women. CONCLUSIONS: Although it is more expensive than the Aylesbury spatula and the cytology brush the Cervex broom has the advantage of allowing a simple one step procedure, thereby reducing the potential for air drying. PMID- 9364179 TI - Hand and lower arm injuries among New Zealand meat workers and use of protective clothing. AB - AIM: To characterise work related hand and lower arm injuries among New Zealand meat processors and to identify practices used for protecting the hands of this group of workers. METHODS: These involved identifying and describing, from Department of Health national data, hand and lower arm injuries sustained by meat workers in New Zealand which resulted in hospitalisation during the period 1979 88, examining injury case records from selected meat processing plants for the period 1987-93 and identifying protective clothing practices in the meat processing industry. RESULTS: A significant increase in the hospitalisation rate for the period 1979-88 was identified (3.3 per 1000 to 5.3 per 1000; chi(2) = 33.14, df = 1, p < 0.001) with cutting and piercing being the most common injury event. Reported use of protective gloves and covers for the lower arm by meat workers was high (93% and 66% respectively) and also probably increased. CONCLUSION: Why injury rates rose during a period in which use of protective gloves reportedly increased is unclear. Possible explanations are discussed. PMID- 9364180 TI - Relevance in health research funding: reality or myth? PMID- 9364181 TI - Failure to obtain informed consent for breast surgery. PMID- 9364182 TI - The management of rectal cancer. PMID- 9364183 TI - The efficacy of inhaled corticosteroids in the management of non asthmatic chronic airflow obstruction. AB - AIMS: The aims of this investigation were to evaluate the efficacy of regular inhaled beclomethasone in the control of symptoms and lung function with non asthmatic smoking related obstructive pulmonary disease and to evaluate the relationship between clinical responses to a short course of oral prednisone and longer term outcomes using inhaled steroid. METHODS: The study was a randomised, double blind, placebo controlled, crossover investigation in 18 patients. The active treatment was inhaled beclomethasone 1000 micrograms given twice daily for three months by metered dose inhaler. At the end of each treatment period, patients received oral prednisone 30 mg/day for ten days. The two treatment phases were separated by a one month washout interval. Peak flow rates, symptom scores and "rescue" bronchodilator use were recorded twice daily. Lung function (FEV1, FVC and lung volumes) and bronchial hyperresponsiveness (PC20 methacholine) were measured at monthly visits. The number of exacerbations requiring intervention therapy were also recorded. RESULTS: There were no consistent benefits attributable to beclomethasone. Lung function was not significantly better as a result of active treatment. Sputum production improved but other symptom scores were similar during active and placebo therapy. Three patients exhibited an increase in FEV1 of 15% or more during active treatment but did not do so when oral prednisone was administered immediately after the period of placebo treatment. A further three patients showed an improvement in FEV1 of 15% or more with oral prednisone but failed to improve during treatment with inhaled beclomethasone. The predictive value of the "trial of steroid" was 0% and 81.3% for positive and negative outcomes respectively. CONCLUSIONS: Our results indicate that in non-asthmatic chronic obstructive pulmonary disease inhaled corticosteroid fails to achieve significant improvements in either lung function or symptoms. The response to a "trial of steroid" using oral prednisone is not clinically helpful in selecting the small number of patients who may subsequently benefit from this form of therapy. PMID- 9364185 TI - Trainee interns in general practices. AB - AIM: To determine the impact of trainee interns (sixth year medical students) on general practices involved in medical student teaching. METHOD: Postal questionnaires were sent to general practitioners, nurses and receptionists in each of 30 general practices throughout New Zealand. Questionnaires were also sent to patients in practices where a trainee intern was present during the study period. RESULTS: Nearly all of the general practitioners, receptionists and nurses found advantages in having trainee interns. Advantages included enjoyment of teaching and personal satisfaction from student involvement in the practice. Two thirds felt that the advantages would increase if the attachment duration was extended. General practitioners reported an increased level of stress and decrease in productivity, with greater hours at work per week. Remuneration was considered inadequate by a third of the general practitioners. Patients found trainee intern involvement advantageous, with improvement in quality of both care and communication. Disadvantages included longer waiting time and longer appointment time. Younger patients were more likely to find disadvantages than older patients. CONCLUSION: Trainee interns in general practices can have a beneficial impact on the quality of primary care. There are disadvantages for health care professionals and patients, and appropriate compensation (in money or time) is important for community undergraduate medical education to continue to be acceptable. PMID- 9364186 TI - Serology testing for measles: a survey of general practitioners in Southland and Otago. PMID- 9364184 TI - Old paint removal and blood lead levels in children. AB - AIM: To identify risk factors, particularly paint removal and clean up practices, for elevated blood lead levels in children, 12 to 24 months old, living in Wellington city. METHODS: Children living in residences more than 50 years old, where residential paint removal had taken place in the last two years, were recruited. Care givers were interviewed, a blood sample was taken from the child's arm and a dust wipe sample was collected from the kitchen floor. Blood and dust samples were analysed for lead content. RESULTS: Data were collected for 141 children (75% of those eligible). The mean blood lead level was 0.24 mumol/L (5.06 micrograms/dL). Higher blood levels were associated with lower income of the main family earner, playing outside, eating dirt and parental hobbies involving lead use. Children receiving regular medical treatment were at lower risk of lead absorption. With the exception of paint removal involving blow torches, none of the paint removal, clean up, or disposal practices was more strongly associated than the other methods with elevated blood lead levels in children living in the household. Dust wipes from the kitchen floor had little predictive value for blood lead level. CONCLUSIONS: High temperature methods of paint removal and parental hobbies involving lead are associated with higher lead levels in children. Given the availability of alternative means of paint removal, continuing use of high temperature methods is unnecessary. Further work is needed to assess lead absorption risks associated with hobbies involving lead. PMID- 9364187 TI - Increased requests for help by problem gamblers: data from a gambling crisis telephone hotline. AB - AIM: A report on the rate and profile of calls received by a national gambling telephone hotline for a twelve month period covering six month periods before and after the opening of New Zealand's second casino located in Auckland. METHODS: Data collected by the hotline for normal counselling purposes during the year ended July 31, 1996 were collated and analysed for trends, gambler profiles and reported problem gambling modes. RESULTS: New first time callers accessing the hotline service during the period comprised 732 problem gamblers and 604 significant others of problem gamblers ( 1,336 new callers in total). Numbers of these new callers contacting the service increased from 510 in the first six months to 826 for the second similar period. Problem gamblers and significant others of problem gamblers reported relatively specific problem modes, rather than generalised problem gambling behaviour. Reported problem modes were track (horse and dog) racing comprising 25% of problem modes, video gambling machines ('poker' machines) 49%, casinos 24% and other modes 2%. New callers increased by 62% in the second half of the year. Casinos increased from 7% of reported problems in the six months prior to the opening of the Auckland casino, to 34% of reported problems for the six months following. Seventy three percent of problem gambler callers were forty years of age or younger, with 15% under 25 years of age. Most problem gambler callers were male (70%), while most significant other callers were male (77%). Maori problem gambler callers comprised 24% of all gamblers and 35% of female problem gambler callers. CONCLUSIONS: Increased use of the gambling crisis hotline by new callers coincided with increased availability of gambling opportunities, particularly gambling machines and a casino, and increased gambling turnover figures. Gambling machines appear to be over represented in reported problems, while reported casino gambling problems increased quickly with availability of the second casino. Maori callers, particularly female Maori, are high users of the gambling crisis hotline. PMID- 9364188 TI - National Centre for Adverse Reactions Monitoring report for the period 1 July, 1994 to 3 June, 1996. PMID- 9364189 TI - The destabilisation of total parenteral nutrition by heparin. How real is the problem? PMID- 9364190 TI - Drug use in dependent opioid users. PMID- 9364191 TI - Collagen-induced arthritis, an animal model of autoimmunity. AB - Collagen induced arthritis (CIA) is an autoimmune model that in many ways resembles rheumatoid arthritis (RA). Immunization of genetically susceptible strains of rodents and primates with type II collagen (CII) leads to the development of a severe polyarticular arthritis that is mediated by an autoimmune response. Like RA, synovitis and erosions of cartilage and bone are hallmarks of CIA, and susceptibility to both RA and CIA is linked to the expression of specific MHC class II molecules. Although not identical to RA, CIA clearly establishes the biological plausibility that an autoimmune reaction to a cartilage component can lead to a chronic, destructive, polyarthritis. Although it is induced in susceptible animals by immunization with heterologous CII, it is the autoreactive component of the immune response that leads to disease. A wealth of evidence indicates that synovitis is initiated by the production of pathogenic autoreactive antibodies capable of fixing and activating complement. The elucidation of the specific amino acid sequences of collagen that are recognized by the MHC molecules has enabled at least two approaches to specific immunotherapy to be considered. Firstly, small synthetic peptides representing dominant epitopes have been used as effectively as the original antigen as a tolerogen. The rather fastidious physicochemical properties of collagen that make it difficult for its routine use in therapy are thereby circumvented by the use of oligopeptides. Secondly, analysis of the specific amino acid side chains that are involved in MHC contact and TCR recognition enables analog peptides to be devised which can specifically and exquisitely inhibit the response to CII, preventing the onset of arthritis. Further investigations involving this model may contribute to the development of specific immunotherapies in the human disorder. PMID- 9364193 TI - Inhibition of nitric oxide synthases enhances the effect of ACTH in hemorrhagic shock. AB - In a model of volume-controlled hemorrhagic shock in rats, invariably leading to death within 30 min of bleeding termination, the intravenous (i.v.) bolus injection of ACTH-(1-24) at the dose of 0.16 mg/kg restored cardiovascular and respiratory functions and greatly prolonged survival. I.v. or intracerebroventricular (i.c.v.) treatment with NG-nitro-L-arginine methylester (L-NAME), a non-isoform-selective inhibitor of nitric oxide synthases (NOSs), at the doses of 2.5-10 mg/kg i.v. or 0.015-0.135 mg/kg i.c.v., as well as i.v. treatment with S-methylisothiourea (SMT), a selective inhibitor of the inducible isoform of NOS, at the doses of 0.001-3 mg/kg, dose-dependently improved cardiovascular and respiratory functions and potentiated the effect of a subthreshold dose (0.02 mg/kg) of ACTH-(1-24). On the other hand, either intraperitoneal or i.c.v. pretreatment with L-arginine, the substrate of NOSs, prevented the effect of ACTH-(1-24). These data suggest that inhibition of NO overproduction is involved in the mechanism of action of ACTH-(1-24) in shock reversal. PMID- 9364192 TI - Stereospecific activity and nature of metabolizing esterases for propranolol prodrug in hairless mouse skin, liver and plasma. AB - Cutaneous stereoselective hydrolyses of ten ester prodrugs of propranolol in hairless mouse were compared to those in liver and plasma. On the basis of protein content, the hydrolysis rate was greatest with liver homogenate followed by plasma and skin homogenate. The buffer showed the slowest and non stereoselective hydrolysis. However, skin showed very high stereoselectivity (R/S ratio: 6.7-18.4) as compared with liver (0.7-2.0) and plasma (1.7-4.7). The microsomal esterase activity was higher than cytosolic esterase in liver, while an opposite relation was observed in skin. The smaller Km and larger Vmax values of the (R) isomer than those of the (S) isomer of caproyl- and/or butyryl propranolol were found in skin and plasma, while Km was the same between (R) and (S) isomers in liver. Enzyme inhibition studies indicated that the carboxylesterases were primarily involved in prodrug hydrolysis in liver. On the other hand, skin and plasma were found to be rich in both carboxylesterases and cholinesterases. Interestingly, the (R) isomer was more sensitive towards butylcholinesterase in skin and plasma, while (S) isomer was more sensitive towards carboxylesterase in plasma. Moreover, no stereoselective inhibition was observed in liver. These data indicated that the hydrolyzing nature of skin esterases responsible for propranolol prodrug was sensitive against stereochemical configuration and more similar to those in plasma esterases than liver esterases. PMID- 9364194 TI - Evidence for participation of gliostatin/platelet-derived endothelial cell growth factor in gastric ulcer healing. AB - Gliostatin (GLS)/Platelet-derived endothelial cell growth factor (PD-ECGF) is a protein factor that has angiogenic and thymidine phosphorylase activity. It has been recently demonstrated to be related to disease activity in rheumatoid arthritis. However, its physiological role in the gastric mucosa is unknown. In the present study, concentrations of this protein in human gastric mucosa and plasma were evaluated. Further, the effect of purified human GLS/PD-ECGF on experimental ulcer healing was investigated in the rat. The human plasma concentration of GLS/PD-ECGF was significantly higher in patients with intractable gastric ulcer than in patients with significant resolution. The tissue content was significantly higher at the gastric ulcer edge than in either the fundic or pyloric region. GLS/PD-ECGF infusion delayed ulcer healing in a dose-dependent manner. These results suggest that gastric tissue and/or circulating GLS/PD-ECGF may participate in pathology and etiology of gastric ulcers and that this mechanism may relate to the pathogenesis of RA. PMID- 9364195 TI - Polyenylphosphatidylcholine decreases alcoholic hyperlipemia without affecting the alcohol-induced rise of HDL-cholesterol. AB - In ethanol-fed rats, supplementation of the diet with soybean polyenylphosphatidylcholine (3 g/liter for 21 days) markedly decreased postprandial VLDL-triglycerides and both VLDL- and LDL-cholesterol levels, whereas it maintained high levels of HDL-cholesterol, compared to an equivalent intake of choline and polyunsaturated fatty acids. By contrast, there were no changes in the serum lipoproteins of the pair-fed controls. The prevention of alcoholic hypertriglyceridemia was associated with marked attenuation of the alcoholic fatty liver and it occurred despite a slight increase in fat absorption. Thus, the administration of polyenylphosphatidylcholine not only attenuates the hepatotoxicity of ethanol, but also increases the HDL/LDL cholesterol ratio, which may be beneficial for the prevention of atherosclerosis and coronary heart disease. PMID- 9364196 TI - Visualization of gene expression of prolactin receptors (PRL-R) by in situ hybridization, in Typhlonectes compressicaudus, a gymnophionan amphibian. AB - The expression of the short and long forms of prolactin receptors (PRL-R) mRNA was studied in various types of tissue from Typhlonectes compressicaudus, an amphibian, by quantitative in situ hybridization. Both forms were expressed in all the types of tissues studied. In the liver, small intestine and hypophysis, the mRNA coding for the short form of PRL-R was more strongly expressed than the mRNA coding for the long form and vice-versa for the stomach, spleen and kidneys. In the female liver, quantification showed a higher value of mRNA expression mid way through pregnancy than during the sexual inactivity period. This result was found to be correlated with the reserve function of the liver. In the kidney and small intestine, the presence of PRL-R was correlated with the hydromineral function. A comparison with certain mammals was also established. These results confirm the ubiquity of PRL effects on metabolic regulation, and suggest a phylogenic conservation of its receptors. PMID- 9364197 TI - Deep cervical lymph flow following the infusion of mannitol in rabbits. AB - Jugular lymph flow of anesthetized rabbits in response to infusion of mannitol solutions differing in osmolarity were measured. Either an isotonic (310 mosmol), hypotonic (100 mosmol), or hypertonic (605 mosmol) mannitol solution was infused into either the internal carotid artery (ICA) or the right lateral ventricle (RLV). Lymph was collected continuously and measured over a 60 min preinfusion period, as well as during mannitol infusion and intermittent recovery periods. The mean peak flow rates of hypertonic infusion for the first 30 min via ICA and RLV were 2.2 +/- 0.4 (12% decrease) and 5.0 +/- 1.0 microliter/min (72% increase), over those of isotonic infusates which were 2.5 +/- 0.3 microliters/min (via ICA) and 2.9 +/- 0.5 microliters/min (via RLV), respectively. In contrast, lymph flow rates of hypotonic infusate for the first 30 min via ICA and RLV were 3.9 +/- 0.8 microliters/min and 2.3 +/- 0.4 microliters/min, respectively. A decrease both in intracranial pressure and in lymph flow following hypertonic mannitol infusion via ICA were observed. However, intracranial pressure and lymph formation were increased following hypertonic infusion via RLV. The results indicate that the changes in jugular lymph flow could be affected by the changing in osmolarity of mannitol infusate. PMID- 9364198 TI - Investigation of the effects of 50 Hz magnetic fields on purified human hematopoietic progenitors. AB - Epidemiological reports suggest a possible association between exposure to extremely low frequency electromagnetic fields (ELF-EMFs) and the frequency of leukemia in men working in the field of electricity or in children living near power lines. At present, there is no experimental evidence for such an association. In this study we investigated the effects of 50 Hz EMFs (sinusoidal EMF of 10 microT or 1 mT) on human purified hematopoietic progenitor cells which are the first targets of a leukemogenic process. The results failed to reveal any significant changes in cell proliferation, cell kinetics, ultrastructure or clonogenic potential of these progenitors which could be related to a leukemogenic effect. PMID- 9364199 TI - Effects of nitric oxide on leukotriene D4 decreased bile secretion in the perfused rat liver. AB - Nitric oxide (NO) and leukotrienes are potent vasoactive agents that are involved in the control of portal blood flow. The present study investigated the role of leukotriene D4 and NO in a non-recirculating constant pressure rat liver perfusion model to analyse their interchanges on portal flow and bile secretion. The addition of leukotriene D4 (20 nM) to the perfusate for 5 minutes resulted in a decrease in portal blood flow (-55.3%), in bile flow (-24.4%) as well as bile acid release (-35.2%). In parallel, leukotriene D4 increased glucose output. The administration of a lower dose of leukotriene D4 (5 nM) reduced the respective parameters to a lesser degree, indicating dose-dependence. The addition of NO via the infusion of sodium nitroprusside (0.05 mM, 1 mM) reduced the effect of leukotriene D4 on portal flow, bile flow and bile acid secretion whereas the leukotriene D4 effects on hepatic glucose output remained unaffected. Correlation coefficient between decrease in portal flow and reduction of bile flow by infusing leukotriene D4 was R = 0.91, while in the presence of sodium nitroprusside R = 0.85. These results suggest that the leukotriene D4-induced cholestasis is dependent on portal flow. In contrast, hepatic vasoconstriction does not contribute to glycogenolysis stimulated by leukotriene D4 in the perfused liver. PMID- 9364200 TI - Quantification of singlet oxygen from hematoporphyrin derivative by electron spin resonance. AB - The mechanism of the generation and the quantitative analysis of singlet oxygen (1O2) formed by the exposure of a hematoporphyrin derivative (HpD) to light was re-evaluated by electron spin resonance (ESR) combined with 2,2,6,6,-tetramethyl 4-piperidine (TMPD). The change from TMPD to 2,2,6,6,-tetramethyl-4-piperidine-N oxide (TAN) has been reported to depend on singlet oxygen. However, we confirmed that this reagent also react with superoxide anion (O2-) and hydroxyl radicals (OH). Therefore, the reactions between TMPD and 1O2, O2- and OH were re-examined using a kinetic approach. We found that the generation of TAN was proportional to the concentration of TMPD and HpD, as well as to the duration and strength of the illumination. The generation of TAN was not inhibited by dimethyl-sulfoxide (DMSO) or superoxide dismutase (SOD). The reaction rate between TMPD and 1O2 was determined to be 5.0 x 10(-7) M min-1. The generation of 1O2 from HpD was 2.7 x 10(-7) M min-1 under our conditions. The competitive reaction observed between 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and TMPD for O2- or OH shows that TMPD reacts with both forms of active oxygen, but gave no ESR signal. The second-order reaction rate constant of TMPD between O2- and OH was calculated as 73 M-1 s-1 and 1.5 x 10(9) M-1 s-1, respectively. The photochemical generation of 1O2 from methylene blue, another sensitizer, was also demonstrated by this method. These results show that ESR signal of TAN can be used for the highly selective monitoring of 1O2. PMID- 9364201 TI - In vitro and in vivo protective effect of honokiol on rat liver from peroxidative injury. AB - Honokiol, a compound extracted from the Chinese medicinal herb Magnolia officinalis, has a strong antioxidant effect on the inhibition of lipid peroxidation in rat heart mitochondria. To investigate the protective effect of honokiol on hepatocytes from peroxidative injury, oxygen consumption and malondialdehyde formation for in vitro iron-induced lipid peroxidation were assayed, and the mitochondrial respiratory function for in vivo ischemia reperfusion injury were evaluated in rat liver, respectively. The inhibitory effect of honokiol on oxygen consumption and malondialdehyde formation during iron-induced lipid peroxidation in liver mitochondria showed obvious dose dependent responses with a concentration of 50% inhibition being 2.3 x 10(-7) M and 4.96 x 10(-7) M, respectively, that is, 550 times and 680 times more potent than alpha-tocopherol, respectively. When rat livers were introduced with ischemia 60 min followed by reperfusion for 60 min, and then pretreated with honokiol (10 micrograms/kg BW), the mitochondrial respiratory control ratio (the quotient of the respiration rate of State 3 to that of State 4) and ADP/O ratio from the honokiol-treated livers were significantly higher than those of non treated livers during reperfusion. The dose-dependent protective effect of honokiol on ischemia-reperfusion injury was 10 microgram-100 micrograms/Kg body weight. We conclude that honokiol is a strong antioxidant and shed insight into clinical implications for protection of hepatocytes from ischemia-reperfusion injury. PMID- 9364202 TI - Chronic imipramine treatment downregulates IR1-imidazoline receptors in rat brainstem. AB - One subtype of imidazoline receptors (IR1) is similar to alpha 2-adrenoceptors (alpha 2 AR) based on their high affinity for clonidine and related imidazoline compounds. On the other hand, IR1 possess low affinity for norepinephrine (NE) and other catecholamines. Imidazoline receptors have also been found to be over expressed in plasma membranes from platelets and brain tissues of depressed patients. Over-expression of IR1 in platelet membranes of depressed patients became normalized after various antidepressant treatment to the patients. Herein, the prototypic antidepressant, imipramine (IMI), has been studied in regard to its treatment effects on [125I]p-iodoclonidine binding to both alpha 2 AR and IR1 in rat brainstem membranes. No effects of chronic IMI treatment were found on brainstem alpha 2 AR binding sites (Bmax and/or KD parameters unchanged) after 25 days of daily injections (i.p. IMI 20 mg/kg/day). However, IMI induced a decrease in the density (Bmax measured under NE mask) of brainstem IR1 sites, with no change in KD. Downregulation of IR1 sites was dose-dependent (minimal effective dose of i.p. IMI was 10 mg/kg/day) and time-dependent (> 16 days of treatment). These results implicate brainstem IR1 in the chronic effects of antidepressants. PMID- 9364203 TI - Omega-3 polyunsaturated fatty acids inhibit migration of human vascular smooth muscle cells in vitro. AB - Arterial smooth muscle cell migration from the media to the intima is a crucial process in the pathogenesis of atherosclerosis. Platelet-derived growth factor (PDGF) has been proposed to play a key role in the development of advanced atherosclerotic lesions by stimulating the migration and proliferation of vascular smooth muscle cells. Polyunsaturated fatty acids (PUFA) of the omega-3 series, extracted from fish oil has been shown to have beneficial effects on atherosclerosis. In this study, we evaluated the effects of omega-3 PUFA on the migration of human aortic smooth muscle cell (hASMC) in vitro. The migration assay was performed according to the Capsoni's method using transwell culture plates. PDGF, fibrinogen or 10% FCS significantly stimulated hASMC migration, however, omega-3 PUFA significantly inhibited PDGF-induced migration of hASMC. These results suggest that the inhibitory effect of omega-3 PUFA on cell migration may be an important aspect by which omega-3 PUFA exerts its antiatherosclerotic influence. PMID- 9364204 TI - Intratumoral differences in methotrexate levels within human osteosarcoma xenografts studied by microdialysis. AB - A central tenet in oncology is the assumed relationship between drug concentration and cytotoxicity. Determinations of drug levels in tumor tissues are, however, generally not undertaken. Microdialysis is a method where continuous drug monitoring may be achieved by sampling of low molecular weight substances from the extracellular space. By employing this technique it is possible to observe variable drug levels within tissues, including tumors, over time. Herein, we present results from a nude rat model where subcutaneous human osteosarcoma xenografts were established prior to the administration of the antifolate methotrexate as an intravenous infusion. Significant differences in drug exposure within single tumors were evident. Generally, peak drug concentrations were lower and drug efflux slower from the center of the tumors as compared to the periphery. The use of microdialysis could be an important tool for optimizing current strategies in anticancer chemotherapy. PMID- 9364205 TI - Association of a murine chromosome 9 locus (Psl1) with susceptibility to mouse skin tumor promotion by 12-O-tetradecanoylphorbol-13-acetate. AB - It has been known for many years that there are dramatic differences in the susceptibility of mouse stocks and strains to two-stage skin carcinogenesis and that these differences are due the animals' responsiveness to tumor-promoting agents. In earlier studies using several inbred mouse strains, we found that susceptibility to skin tumor promotion by phorbol esters such as 12-O tetradecanoylphorbol-13-acetate (TPA) is a multigenic trait. To extend this work, we conducted a genome scan of (C57BL/6 x DBA/2)F1 x C57BL/6 mice previously scored for sensitivity to skin tumor promotion by TPA. As a result of this scan, we now report an association of increased TPA promotion susceptibility with inheritance of the DBA/2 alleles of markers on the distal portion of mouse chromosome 9. Additional linkage analyses using (C57BL/6 x DBA/2)F2 and B x D recombinant inbred mice confirmed this association and suggested that a TPA promotion susceptibility locus maps near D9Mit51 (LODw = 4.1). We designated this locus promotion susceptibility locus 1 (Ps/1). PMID- 9364206 TI - Reduced p53 dosage associated with mammary tumor metastases in C3(1)/TAG transgenic mice. AB - Transgenic mice expressing the simian virus 40 large T-antigen (TAG) under the regulatory control of the rat prostatic steroid binding protein C3(1) gene develop mammary carcinomas (in females) and prostate carcinomas (in males). The development of carcinomas occurs several months after the appearance of dysplastic lesions, suggesting that TAG is necessary but insufficient for tumor formation and that other genetic events are involved in this process. TAG is known to bind to p53 and to result in its functional inactivation, which is believed to be a critical step in TAG-induced transformation. We investigated whether the TAG-p53 interaction is rate limiting in the development of phenotypic changes in these transgenic mice by crossing C3(1)/TAG transgenics with mice carrying null mutations of the p53 gene. TAG-expressing animals with a p53+/- genotype developed much more aggressive mammary tumors, as evidenced by increased numbers and size of metastases, than did TAG-expressing animals carrying two wild type p53 alleles. While p53 was expressed in primary tumors, p53 expression appeared to be reduced or lost in many metastases in mice carrying either the p53+/+ or p53+/- genotypes. The tumorigenic process did not appear to be due to the loss of the second wild-type p53 allele or the gain of dominant oncogenic mutations in p53, as no mutations were detected in either primary or metastatic tumors by polymerase chain reaction--single-strand conformation polymorphism analyses. These findings suggest that despite the presence of TAG, p53 levels influence the characteristics of the late stages of mammary tumor growth and accelerate metastases. Functional loss of p53 and not p53 mutations participates in TAG-induced mammary carcinoma development and progression. PMID- 9364207 TI - Morphological transformation caused by a partial sequence of U5 small nuclear RNA. AB - My colleagues and I have reported that a small nuclear RNA, U5, can cause transformation of and chromosomal aberrations in rat fibroblast 3Y1 cells. In the study described here, I found that a partial U5 sequence, the 3' half of the first stem structure (designated RNA3S), transformed the cells morphologically at a high frequency when expressed with a poly(A) tail (RNA3S+). The transformation critically depended upon a polypurine sequence in RNA3S+. The expressed RNA3S+ was associated with polysomes. The transformed cells did not exhibit significant frequencies of chromosome aberrations when compared with control cells, suggesting that the transformation occurs without significant induction of chromosome damage. Heterogeneous subcolonies emerged in monolayers when the morphologically transformed cells were subcultured and maintained at postconfluence. Cells from subcolonies acquired the ability to form small colonies in soft agar and tumors in nude mice, suggesting that RNA3S+ can drive the cells into the neoplastic stage. RNA3S+ also conferred morphological alterations and a growth advantage and decreased levels of fibronectin protein synthesis in human HeLa cells, confirming the transforming potential of the RNA. RNA3S+ transformation may therefore be a useful model system for studying a transformation process. PMID- 9364208 TI - Role of the H19 gene in Syrian hamster embryo cell tumorigenicity. AB - Carcinogen-induced transformation in Syrian hamster embryo (SHE) cells is a multistage process characterized by specific genetic alterations at each stage in the transformation process. Loss of H19 gene expression is one of the earliest events observed, occurring in approximately 75% of the morphologically transformed cells and the subsequently derived tumorigenic cells. To investigate the effect the loss of H19 expression has on SHE cell tumorigenicity, H19 expression was reestablished in a tumorigenic SHE cell lineage that lacked H19 expression. H19 reexpression had little effect on cellular growth in vitro but did retard tumor growth in nude mice. Analysis of the tumors that did develop from cells containing the H19 gene indicated that loss of exogenous H19 gene expression was probably due to changes in DNA methylation. These results demonstrate that alterations in H19 gene expression play an important role in SHE cell tumorigenicity. PMID- 9364209 TI - Alterations in the Ha-ras-1 and the p53 pathway genes in the progression of N methyl-N-nitrosourea-induced rat mammary tumors. AB - Well-differentiated mammary carcinomas carrying mutated Ha-ras-1 oncogenes arise frequently in pubescent rats exposed to the direct-acting methylating agent N methyl-N-nitrosourea (MNU). When these tumors are serially transplanted, they acquire more aggressive phenotypes. To determine the genetic alterations underlying local invasion, hormone independence, and metastasis, we studied alterations in the Ha-ras-1, p53, and mdm2 genes in successive generations of tumors passaged in intact or ovariectomized rats. Although previous studies have shown that selective amplification of the mutant Ha-ras-1 allele correlates strongly with the acquisition of hormone independence, we found that the acquisition of an invasive phenotype did not depend on mutational activation or amplification of Ha-ras-1. Mutations in the p53 gene were rare. Of a total of 120 primary, locally invasive, hormone-independent, and metastatic tumors tested for mutations in exons 4-9 of the p53 gene, only one mutation was detected in the later passages of an invasive tumor line. No gross gene alteration or amplification was seen in mdm2, a negative regulator of p53 transcription. Thus, the p53 gene is an infrequent mutational target, and amplification of the mdm2 gene does not appear to play a role in initiation or progression of rat mammary tumorigenesis. PMID- 9364210 TI - Gene expression changes associated with chemically induced rat mammary carcinogenesis. AB - Experimentally induced models of breast carcinogenesis in the rat are widely used for studying the biology of breast cancer and for developing and evaluating cancer prevention and control strategies. However, very little is known about gene expression changes that are associated with experimentally induced mammary carcinogenesis. This paper reports the identification, by differential display of mRNA and molecular cloning, of seven cDNA fragments of gene transcripts overexpressed in mammary carcinomas induced by 1-methyl-1-nitrosourea. These genes included the rat homologues of human galectin-7 gene, the human/mouse melanoma inhibitory activity/bovine chondrocyte-derived retinoic acid sensitive protein gene, the mouse stearoyl-CoA desaturase-2 gene, and the mouse endo B cytokeratin/human cytokeratin-18 gene. Although each of these genes has been implicated in some aspect of carcinogenesis in other organs, this paper is the first report of their overexpression in chemically induced mammary carcinomas. Two previously uncharacterized gene transcripts were also identified. A comparison of the expression levels of several genes in mammary carcinomas with those in the normal mammary gland tissue of virgin rats, mid-stage pregnant rats, and of day 1 postpartum lactating dams indicated that the overexpression of several genes observed in mammary carcinomas could not be accounted for by either a difference in the mammary epithelial content between mammary carcinoma and normal mammary tissue or by mammary epithelium-specific proliferation associated with pregnancy. Several genes were also overexpressed in rat mammary carcinomas induced by 7,12-dimethylbenz[a]anthracene but not in azoxymethane-induced rat colon adenocarcinomas. The genes identified in this study may therefore represent mammary carcinoma-specific molecular markers that may be helpful in investigations of mammary carcinogenesis and its prevention. PMID- 9364211 TI - High-affinity binding of the cell cycle-regulated transcription factors E2F1 and E2F4 to benzo[a]pyrene diol epoxide-DNA adducts. AB - Previous studies indicated that DNA adducts formed by a carcinogenic diol epoxide, 7r,8t-dihydroxy-9t, 10t-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), can increase the affinity of the transcription factor Sp1 for DNA sequences that are not normally specific binding sites. It was suggested that adduct-induced bends in the DNA were responsible for this behavior. The cell cycle-regulated transcription factor E2F is also known to bend DNA upon binding. When partially purified E2F was tested in a gel mobility-shift assay, binding to a target DNA containing two consensus E2F-binding sites was enhanced by prior modification of the DNA with BPDE. Recombinant human E2F1, E2F4, and DP1 fusion proteins were affinity purified from bacteria expressing these genes. A combination of either E2F1 or E2F4 with their dimerization partner, DP1, gave preparations that exhibited binding to the E2F site-containing DNA fragment. In both cases, the proteins exhibited much higher apparent affinity for BPDE-modified DNA than for unmodified DNA. In addition, BPDE-modified DNA was a better competitor for the binding than unmodified DNA. Heterologous DNA that contained no consensus E2F binding motifs also competed well for E2F binding when modified with BPDE. In contrast, transcription factor that does not bend DNA appreciably (GAL4) did not show enhanced affinity for BPDE-modified DNA. These findings suggest that numerous transcription factors that bend DNA may bind with anomalously high affinity to sequences that contain carcinogen-DNA adducts. PMID- 9364212 TI - Detection of mRNA encoding xenobiotic-metabolizing cytochrome P450s in human bronchoalveolar macrophages and peripheral blood lymphocytes. AB - Human pulmonary tissue are known to contain enzymes mediating procarcinogen activation. Peripheral blood lymphocytes and bronchoalveolar macrophages (BAMs) have been used as surrogates for the lung in studies involving cytochrome P450 (CYP) parameters, including CYP1A1 inducibility in relation to susceptibility to lung cancer. In this study, a comprehensive view of the expression patterns of xenobiotic-metabolizing CYP forms in human BAMs and peripheral blood lymphocytes was obtained by using gene-specific reverse transcriptase-polymerase chain reaction analysis. These patterns were compared with that in the whole lung. mRNAs of CYP2B6/7, CYP2C, CYP2E1, CYP2F1, CYP3A5, and CYP4B1 were detected in all seven BAM samples studied; however, only the mRNA of CYP2E1 was found consistently in all eight lymphocyte samples. The amounts of amplification products of CYP2B6/7, CYP2C, CYP3A5, and CYP4B1 were low and inconsistent, indicating low levels of expression in lymphocytes. Consistent with previous knowledge, mRNAs of CYP1A1, CYP2B6/7, CYP2E1, CYP2F1, CYP3A5, and CYP4B1 were detected in whole-lung tissue. These results give an overall picture of the expression of CYP genes in the xenobiotic-metabolizing families CYP1, CYP2, and CYP3 in BAMs, peripheral blood lymphocytes, and whole-lung tissue and will aid in directing future studies on the respective protein products. The differences in the CYP gene expression patterns between lung and lymphocytes cast additional doubt on the use of lymphocytes as a surrogate for the lung. PMID- 9364213 TI - bcl-2 enhancement of malignant transformation in mouse epidermal JB6 cells. AB - Increased bcl-2 expression is a common feature of many types of human malignancies, which implies that bcl-2 plays an important role in tumorigenesis. To better understand the molecular mechanisms of bcl-2-induced oncogenesis, we examined the effects of bcl-2 expression on transformation of mouse epidermal JB6 cells induced by the tumor promoter 12-O-tetradecanoylphorbol-13 acetate (TPA). Promotion-sensitive JB6 clone41 cells were transfected with the bcl-2-containing expression vector pD5-neo/bcl-2, and the soft agar growth of bcl-2-transfected cells and control cells were compared. bcl-2 overexpression in JB6 clone41 cells caused a TPA-induced soft-agar growth fivefold greater than the growth of nontransfected or vector-transfected (neo control) cells. bcl-2 expression in the absence of TPA did not lead to colony formation in soft agar. Because the level of the transcription factor activator protein 1 (AP-1) has been shown to be critical for the responsiveness of JB6 cells to TPA-induced transformation, we compared c-jun and c-fos expression as well as the AP-1-binding activity and the AP-1-mediated transactivation of the reporter construct TRE-CAT between bcl-2 expressing cells and control cells. When compared with control cells, bcl-2 transfected cells expressed significantly more c-fos but not c-jun after TPA treatment. Furthermore, the levels of AP-1 and AP-1-induced transactivation of TRE-CAT were greater in bcl-2-transfected cells than in control cells after TPA treatment. These results showed that bcl-2 cooperates with a tumor promoter such as TPA in the induction of malignant transformation in mouse epidermal cells and that bcl-2 enhances soft-agar growth by stimulating signaling pathways that led to increased AP-1 expression. PMID- 9364214 TI - Neoplastic transformation of the endocervix associated with downregulation of lactoferrin expression. AB - The incidence of cervical adenocarcinomas in young women over the last two decades has increased. Even with increasing knowledge of the role of human papillomavirus in the etiology of adenocarcinoma of the cervix, there is a paucity of data concerning the genetic and epigenetic factors that contribute to the histologic features and biologic behaviors of these tumors. Lactoferrin is a basic glycoprotein found in human milk, secondary granules of neutrophils, and many body secretions, and it has been associated with carcinogenesis of the endometrium, breast, and lymphoid systems. In this study, we examined the expression of lactoferrin in normal human endocervical epithelium and in cervical adenocarcinomas in relation to proliferative index, steroid receptor status, p53 protein expression, and apoptosis. Immunohistochemical and in situ studies demonstrated that lactoferrin protein and mRNA were strikingly downregulated upon neoplastic transformation of the endocervix as early as in adenocarcinoma in situ when compared with the prominent expression exhibited by the normal cervical epithelium. Furthermore, neoplastic transformation of endocervical epithelial cells was accompanied by a pronounced stimulation of proliferation and a substantial reduction in the expression of the estrogen and progesterone receptors and p53 but little or no change in the number of apoptotic cells. In conclusion, we identified lactoferrin as a novel cancer-specific marker of endocervical adenocarcinomas that may be useful in the early detection of the disease, prediction of prognosis, and the development of new therapeutic modalities. PMID- 9364215 TI - Suppression of Ki-ras p21 levels leading to growth inhibition of pancreatic cancer cell lines with Ki-ras mutation but not those without Ki-ras mutation. AB - Ki-ras point mutation characteristically occurs frequently in human pancreatic cancer. To clarify the effect of antisense Ki-ras RNA on various pancreatic cancer cell lines, a plasmid expressing an antisense Ki-ras gene fragment (AS-K ras-LNSX) was transduced into seven human pancreatic cancer cell lines (AsPC-1, MIA PaCa-2, PANC-1, PSN-1, BxPC-3, Hs 700T, and Hs 766T) by liposome-mediated transfection. Western blot analysis showed that transfection of AS-K-ras-LNSX led to a significant reduction in the amounts of Ki-ras p21 protein in all the pancreatic cancer cell lines except BxPC-3. The growth of pancreatic cancer cell lines having Ki-ras point mutations (AsPC-1, MIA PaCa-2, PANC-1, and PSN-1) was suppressed after transduction of AS-K-ras-LNSX, whereas the effect of the antisense construct on the growth was not significant in cell lines with a wild type Ki-ras gene (BxPC-3, Hs 700T, and Hs 766T). These results suggest that the pancreatic cancer cells with activated Ki-ras depend heavily on a Ki-ras p21 mediated growth signal pathway for their growth because they were far more susceptible to the suppression of the Ki-ras p21 protein than the cells with wild type Ki-ras. The remarkably increased dependence of the cancer-cell growth circuitry on one or a few crucial regulatory molecules may thus be a common feature of the cancer cells and implies a novel rationale for the targeting of cancer therapy. PMID- 9364216 TI - Early phosphorylation of the retinoblastoma gene product regulates protein binding to the c-fos retinoblastoma control element during T cell activation. AB - Function of the retinoblastoma tumor suppressor protein [pRb] is regulated by phosphorylation during the G1 and S phases of the cell cycle. pRb regulates transcription of several genes, including c-fos. However, since c-fos is regulated during exit from G0, it has remained unclear how pRb participates in c fos regulation. We have identified a protein complex, the retinoblastoma control factor A [RCF-A] which binds to the c-fos retinoblastoma control element [RCE] and is regulated by pRb within 10 min after T cell activation. We demonstrate that pRb control of RCF-A is dependent upon the state of phosphorylation of pRb. pRb becomes hyperphosphorylated on specific peptides at 10 min after mitogenic stimulation and pRb is dephosphorylated by 30 min. This time course coincides with RCF-A DNA binding. RCF-A binds RCE DNA longer when cells are treated with okadaic acid, and okadaic acid prevents pRb dephosphorylation. Dephosphorylated pRb inhibits RCF-A binding in vitro but phosphorylated pRb does not. Thus, in addition to the described G1/S regulation of pRb, transient inactivation by phosphorylation of pRb in T cells may also be important as resting cells leave G0. PMID- 9364218 TI - The inactivation of the XP-C gene does not affect somatic hypermutation or class switch recombination of immunoglobulin genes. AB - The mechanism of somatic hypermutation of immunoglobulin genes is not known, but appears to be linked to transcription and perhaps DNA repair. In order to determine if global DNA repair or the repair of the nontranscribed DNA strand is required for somatic mutation, we have analysed mice whose XP-C gene was inactivated by homologous recombination. Our study shows that hypermutation occurs in XP-C knockout mice with a normal frequency, suggesting that the XP-C gene product is not required for somatic hypermutation. Furthermore, we found that Ig gene switch recombination also is normal in these mice. PMID- 9364217 TI - Decreased IgG-Fc gamma RII dissociation kinetics in the presence of a protein antigen. AB - Total internal reflection fluorescence microscopy has been used to examine the interaction of a mouse monoclonal IgG2b, in the absence and presence of its protein antigen, with mouse Fc gamma RII in substrate-supported planar membranes. Equilibrium association and kinetic dissociation constants were measured for the antibody S6-34.11, which is specific for bovine prothrombin fragment 1 (BF1). These measurements showed that BF1 induces a statistically significant decrease (30-40%) in the IgG-Fc gamma RII dissociation kinetics. A corresponding increase in the equilibrium association constant was not observed, perhaps because the statistical accuracy of the equilibrium measurements is lower than that for the kinetic measurements. The consequences of these results for understanding the mechanism by which macrophages recognize and ingest opsonized targets are discussed. PMID- 9364219 TI - Is celiac disease due to molecular mimicry between gliadin peptide-HLA class II molecule-T cell interactions and those of some unidentified superantigen? AB - This paper presents a new hypothesis for the etiology and pathogenesis of celiac disease (CD). It is our contention that CD is triggered by the binding of one or more gliadin peptides to CD-associated HLA class II molecules. Furthermore, we propose that these putative CD peptides bind to oligosaccharide residues on HLA class II molecules distal to the peptide-binding groove invoking recognition and binding by specialized subsets of gamma delta T cell receptor-bearing lymphocytes. The binding of these gamma delta T cells serves as a signal for abrogation of oral tolerance to ingested proteins setting in motion a series of immune responses directed against the small intestinal epithelium of CD patients. CD patients are victimized by this self-distructed immune response because of inheritance of certain combinations of HLA-DQ and DR haplotypes. Dimers encoded by HLA-DR haplotypes may be the primary restriction elements for lectin-like, gliadin peptides while the degree of immune suppression (or lack thereof) to ingested gliadins is governed by inherited HLA-DQ haplotypes. Finally, we speculate that molecular mimicry between one or more gliadin peptides and some, as yet unidentified, bacterial or viral superantigen plays a role in disease pathogenesis. PMID- 9364220 TI - Antigenic determinants reacting with rheumatoid factor: epitopes with different primary sequences share similar conformation. AB - Polyclonal or monoclonal human IgM rheumatoid factors (RF) react with eight antigenic sites on the CH3 IgG domain, four sites on CH2 and two on human beta 2 microglobulin. All 14 of these RF-reactive epitopes are linear 7-11 amino acid peptides with different primary sequence. We questioned whether RF reactivity with such a variety of epitopes showing no obvious sequence homology might result from conformational similarities shared by various RF-reactive regions. Strong support for this concept was obtained using rabbit antisera as well as mouse mAbs to individual CH3, CH2 or beta 2m RF-reactive peptides. Major cross-reactivity was demonstrated between most of the 14 different CH3, CH2, or beta 2m RF reactive peptides using individual anti-epitope antibodies. Molecular modelling studies of these peptides showed striking similarities in three-dimensional shape among many RF-reactive peptides. Main-chain atoms rather than side chains seemed to contribute most directly to conformational similarity. Molecular simulation studies on control peptides showed no conformational similarities with RF reactive peptides. Our studies indicate that autoantibodies such as RF recognize main-chain conformations of reactive epitopes and react with a number of antigenic determinants of quite different primary sequence but similar main chain conformations. PMID- 9364221 TI - Structural differences among serum IgA proteins of chimpanzee, rhesus monkey and rat origin. AB - Asparagine-linked sugar chains were quantitatively released from chimpanzee, Rhesus monkey and rat IgA proteins as oligosaccharides by hydrazinolysis, converted to radioactive oligosaccharides by reduction with NaB3H4, and separated into neutral and two acidic fractions by paper electrophoresis. The acidic oligosaccharides were converted to neutral ones by sialidase digestion, indicating that they are sialyl derivatives. However, the content of N-acetyl and N-glycolyl neuraminic acids was different among three species. The neutral and sialidase-treated acidic oligosaccharides were fractionated by Bio-Gel P-4 column chromatography in combination with linkage-specific sequential exoglycosidase digestion. Although IgA molecules from these species have mainly biantennary complex-type sugar chains, the contents of fucose and bisecting N acetylglucosamine residues displayed marked species differences. In addition to these sugar chains, a small amount of the high mannose-type sugar chains was detected in chimpanzee and rat, but not in Rhesus monkey IgA. These results indicated that the processing of asparagine-linked sugar chains of IgA is different in each species. PMID- 9364222 TI - Disturbed by study of renal failure in dogs. PMID- 9364223 TI - What is your diagnosis? Multiple nodular mural filling defects in the mucosa of the distal portion of the colon and rectum. PMID- 9364224 TI - ECG of the month. Sinus arrhythmia in a dog. PMID- 9364225 TI - Habit as a defense in a veterinary malpractice suit. PMID- 9364226 TI - Antibodies to Ehrlichia equi in dogs from the northeastern United States. AB - OBJECTIVE: To determine whether dogs living in tickinfested areas of the northeastern United States had been exposed to Ehrlichia equi, an etiologic agent of granulocytic ehrlichiosis. DESIGN: Analyses of dog sera. ANIMALS: 106 ill dogs and 12 clinically normal dogs. PROCEDURE: Antibodies to E equi were detected by indirect fluorescent antibody staining methods and western blot analyses. RESULTS: 10 of 106 (9.4%) sera tested from ill, privately owned dogs living in tick-infested areas of Connecticut and New York state had antibodies to E equi, a member of the E phagocytophila genogroup. Titration end points ranged from 1:80 to 1:1,280. Immunoblots revealed antibodies to proteins of E equi having molecular masses of predominantly 29, 40, 44, 105, 120, and 160 kd. There was good agreement between results of serologic testing methods, but use of the human isolate (NCH-1 strain) in western blot analyses detected 2 additional seropositive dogs found to be negative by indirect fluorescent antibody staining methods with the MRK strain. CLINICAL IMPLICATIONS: Dogs living in areas where ixodes scapularis is abundant may be exposed to multiple pathogens, such as E equi or Borrelia burgdorferi. Although mild or subclinical infections with E equi may develop, dogs with marked leukopenia, thrombocytopenia, or anemia should be viewed as possibly having ehrlichiosis. Laboratory diagnosis should include examinations for morulae in granulocytes or monocytes in addition to serologic analyses. PMID- 9364227 TI - Electrocardiographic characteristics of endurance-trained Alaskan sled dogs. AB - OBJECTIVE: To determine electrocardiographic characteristics of endurance-trained Alaskan sled dogs. DESIGN: Case series. ANIMALS: 319 Alaskan sled dogs entered to compete in the 1994 Iditarod Trail Sled Dog Race. PROCEDURE: ECG were recorded while dogs were standing and were analyzed digitally. RESULTS: Amplitudes of P waves (median, 0.40 mV; fifth to 95th percentile range, 0.11 to 0.61 mV) and R waves in lead II (median, 3.02 mV; fifth to 95th percentile range, 1.49 to 4.40 mV) were high; durations of P waves in lead II (median, 61 milliseconds; fifth to 95th percentile range, 36 to 96 milliseconds), QRS complexes (median, 64 milliseconds; fifth to 95th percentile range, 52 to 80 milliseconds), and QT intervals (median, 236 milliseconds; fifth to 95th percentile range, 208 to 277 milliseconds) were prolonged. Median value for mean axis of ventricular depolarization was 57 degrees (fifth to 95th percentile range, 19 to 90 degrees). Atrial and ventricular premature depolarizations were observed in 3 (0.9%) and 4 (1.3%) of 319 dogs, respectively, and paroxysmal ventricular tachycardia was detected in 1 (0.3%). CLINICAL IMPLICATIONS: Results suggest that electrocardiographic characteristics of endurance-trained Alaskan sled dogs differ from those reported for nonsled dogs, probably as a result of effects of endurance training on heart size. Some of these characteristics could be mistaken as evidence of pathologic cardiac hypertrophy. PMID- 9364228 TI - Reliability of early radiographic evaluations for canine hip dysplasia obtained from the standard ventrodorsal radiographic projection. AB - OBJECTIVE: To determine reliability of preliminary evaluations for canine hip dysplasia (CHD) performed by the Orthopedic Foundation for Animals on dogs between 3 and 18 months of age. DESIGN: Retrospective analysis of data from the Orthopedic Foundation for Animals database. ANIMALS: 2,332 Golden Retrievers, Labrador Retrievers, German Shepherd Dogs, and Rottweilers for which preliminary evaluation had been performed between 3 and 18 months of age and for which results of a definitive evaluation performed after 24 months of age were available. PROCEDURE: Each radiograph was evaluated, and hip joint status was graded as excellent, good, fair, or borderline phenotype or mild, moderate, or severe dysplasia. Preliminary evaluations were performed by 1 radiologist; definitive evaluations were the consensus of 3 radiologists. Reliability of preliminary evaluations was calculated as the percentage of definitive evaluations (normal vs dysplastic) that were unchanged from preliminary evaluations. RESULTS: Reliability of a preliminary evaluation of normal hip joint phenotype decreased significantly as the preliminary evaluation changed from excellent (100%) to good (97.9%) to fair (76.9%) phenotype. Reliability of a preliminary evaluation of CHD increased significantly as the preliminary evaluation changed from mild (84.4%) to moderate (97.4%) CHD. Reliability of preliminary evaluations increased significantly as age at the time of preliminary evaluation increased, regardless of whether dogs received a preliminary evaluation of normal phenotype or CHD. CLINICAL IMPLICATIONS: Results suggest that preliminary evaluations of hip joint status in dogs are generally reliable. However, dogs that receive a preliminary evaluation of fair phenotype of mild CHD should be reevaluated after 24 months of age. PMID- 9364229 TI - Prognostic factors for surgical treatment of soft-tissue sarcomas in dogs: 75 cases (1986-1996). AB - OBJECTIVE: To determine results of surgery for treatment of soft-tissue sarcomas in dogs and to identify prognostic variables that can be used to predict outcome. DESIGN: Retrospective case series. ANIMALS: Dogs with soft-tissue sarcomas that had surgical treatment only. PROCEDURE: Records were examined for clinically relevant data. Histologic samples were reviewed. Follow-up information was obtained by physical examination or telephone conversations with referring veterinarians or owners. RESULTS: 75 dogs with soft-tissue sarcomas of the trunk and extremities were identified. Median age was 10.6 years. Malignant peripheral nerve sheath tumors were of a significantly lower grade than other tumors. Tumors recurred locally in 11 of 75 (15%) dogs. Evaluation for lack of tumor cells at surgical margins was prognostic for local recurrence. Metastatic disease developed in 13 of 75 (17%) dogs. Tumor mitotic rate was prognostic for development of metastasis. Twenty-five of 75 (33%) dogs died of tumor-related causes. Percentage of tumor necrosis and tumor mitotic rate were prognostic for survival time. Median survival time was 1,416 days. CLINICAL IMPLICATIONS: On the basis of a low local recurrence rate and high median survival time, wide excision of tumor margins or radical surgery appeared to be an effective means for managing soft-tissue sarcomas of the trunk and extremities. Analysis of histologic characteristics for prognosis supported use of preoperative biopsy. Surgical margins should be evaluated, and early use of aggressive surgery is indicated in the management of soft-tissue sarcomas in dogs. PMID- 9364230 TI - Ovarian torsion associated with granulosa-theca cell tumor in a mare. AB - A 12-year-old Morgan mare was examined because of stallion-like behavior of 45 days' duration. Palpation per rectum and transrectal ultrasonographic examination revealed a large left ovary with multiple cystic areas and crepitus. A granulosa theca cell tumor was suspected. During hospitalization for further evaluation of the affected ovary, the mare developed signs of abdominal pain. Exploratory surgery revealed a large left ovary, which was black with a necrotic and friable surface, and a 720 degrees clock-wise torsion of the ovarian pedicle. Torsion was corrected, and oophorectomy was performed. The mare recovered satisfactorily from surgery. Histologic diagnosis was granulosatheca cell tumor with marked diffuse necrosis. To our knowledge, torsion of the ovarian pedicle has not been reported in the veterinary literature. However, it is not uncommon in women. Ovarian torsion seems to develop in association with neoplasia, cysts, and ovarian hyperstimulation syndrome. Ovarian torsion should be considered as a differential diagnosis for mares with a known ovarian pathologic change such as neoplasia or abscess if signs of abdominal pain are evident. PMID- 9364231 TI - Use of full cortical allograft to repair a metatarsal fracture in a foal. AB - A 4-month-old Quarter Horse colt was admitted for repair of an open, comminuted fracture of the proximal portions of the diaphyses of the left second, third, and fourth metatarsal bones. Initial repair included internal fixation and cancellous bone graft. However, the third metatarsal bone became infected and failed to heal. After removal of infected portions of the bone, a 5-cm, fullthickness cortical allograft was placed in the defect. Rigid internal fixation provided stability for the allograft and remaining fracture fragments so that the horse was able to bear weight on the second and fourth metatarsal bones. The allograft was ultimately resorbed; however, appositional bone growth permitted a massive, functional metatarsal bone to form that incorporated the second, third, and fourth metatarsal bones. The colt went on to compete successfully, long term, as a show horse. PMID- 9364232 TI - Evaluation of exploratory laparotomy in young horses: 102 cases (1987-1992). AB - OBJECTIVE: To determine, in a population of young horses, whether a variation exists among neonates, sucklings, weanlings, and yearlings regarding recovery from anesthesia, short- and long-term survival rates, and postoperative adhesion formation following exploratory laparotomy. DESIGN: Retrospective study. ANIMALS: 102 horses < 25 months old that underwent exploratory laparotomy. PROCEDURE: Pre , intra-, and postoperative information was retrieved from medical records, conversations with referring veterinarians, owners, or trainers, and race records. Survival rates (recovery from anesthesia and short- and long-term survival) were compared with age, lesion type, lesion location, surgical procedure, and development of clinically important postoperative intestinal adhesions. RESULTS: Of the 73 horses that recovered from anesthesia, 69 were available for follow-up. Of the 69 horses, 7 (10%) died of complications associated with formation of intestinal adhesions. Age did not affect incidence of adhesion formation, lesion type, lesion location, or surgical procedure performed. Long-term survival rate after surgery for correction of a small intestinal lesion was 34%, whereas that after surgery for correction of a large intestinal lesion was 65%. CLINICAL IMPLICATIONS: Surgical treatment of colic in young horses resulted in survival rates that are similar to those reported for mature horses. The incidence of clinically important postoperative adhesions was greater than that found for young horses in earlier studies. This may be the result of the younger age of our study population. Alternatively, improvements in operative techniques and postoperative management may allow a larger percentage of horses to survive long term and develop complications such as adhesion formation. PMID- 9364233 TI - Use of age and serum gamma-glutamyltransferase activity to assess passive transfer status in lambs. AB - OBJECTIVE: To develop an algorithm for predicting passive transfer status of lambs of various ages, using the lamb's age and serum gamma-glutamyltransferase (GGT) activity. DESIGN: Prospective study. ANIMALS: 51 Suffolk, Columbia, and crossbred lambs from 1 to 16 days old. PROCEDURE: Serum was obtained from all lambs. Serum GGT activity was measured, using a commercially available kit. Serum IgG concentration was determined by use of radial immunodiffusion. Day-1 serum IgG concentration was estimated from sample IgG concentration, lamb age, and the published 14-day half-life of IgG in lambs. Stepwise multivariate regression models were developed to estimate day-1 serum IgG concentration as a function of the natural logarithm of serum GGT activity (In[GGT]) and natural logarithm of lamb age (In[age]) at the time of sampling. These regression models were then used to calculate serum GGT activities that were equivalent to various day-1 IgG concentrations in lambs of various ages. RESULTS: In(GGT) and In(age) were significantly associated with estimated day-1 IgG concentration. Day-1 serum IgG concentration could be predicted using the formula: IgG = -7,686 + 1,366(In[GGT]) + 1,199(In[age]). The model was moderately accurate in predicting serum IgG concentration (R2 = 0.52). CLINICAL IMPLICATIONS: Serum GGT activity can be used to assess passive transfer status of lambs. PMID- 9364234 TI - Evaluation of serum gamma-glutamyltransferase activity as a predictor of passive transfer status in crias. AB - OBJECTIVE: To determine the relationship between serum gamma-glutamyltransferase (GGT) activity and serum IgG concentration in neonatal crias. DESIGN: Prospective observational study. ANIMALS: 21 llama and 4 alpaca crias from 0 to 5 days old. PROCEDURE: Serum GGT activity was measured, using a commercially available kit. Serum IgG concentration was determined by use of radial immunodiffusion. With a serum IgG concentration of 1,000 mg/dl (considered adequate passive transfer), specificity and sensitivity of serum GGT activity in the detection of failure of passive transfer were determined. Regression models were developed to determine the relationship between serum GGT activity and serum IgG concentration. RESULTS: Sensitivity ranged from 0.56 to 0.89, and specificity ranged from 0.88 to 0.31, depending on the value of serum GGT activity chosen as a threshold. Proportion of crias correctly classified ranged from 0.76 to 0.52. Regression models failed to demonstrate a significant relationship between serum GGT activity and serum IgG concentration. CLINICAL IMPLICATIONS: Passive transfer status in crias cannot be accurately predicted on the basis of serum GGT activity. PMID- 9364235 TI - Neurochemical development of the degenerating rat retina. AB - The Royal College of Surgeons' (RCS) rat is an experimental model for a group of hereditary retinal diseases commonly called retinitis pigmentosa. We used postembedding immunocytochemistry to determine the localisation of glutamate, gamma-aminobutyric acid (GABA), glycine, aspartate, glutamine, taurine, and arginine in the RCS rat retina during postnatal development. In addition, we evaluated the uptake characteristics for the three dominant amino acid neurotransmitters, glutamate, GABA, and glycine. Whereas, cellular localisation of all amino acids was similar to control retinas, there were major changes in the level of immunoreactivity, even before eye opening, and well before the onset of visibly detectable photoreceptor degeneration. Two major patterns emerged. First, neurochemical changes evident before degeneration, involving the amino acids glutamate, GABA, aspartate, glutamine, and arginine. Second, neurochemical changes that become evident during photoreceptor degeneration involving the amino acids taurine and glycine. Anomalies in uptake characteristics also become evident during the degeneration phase and are likely to reflect changes in cellular function as a consequence of the degeneration process. Neurochemical changes evident before photoreceptor degeneration involve both glutamate and GABA manufacturing pathways. Muller's cells displayed elevated levels of glutamine and arginine from an early age, and the neuroblastic layer in the RCS retina showed high glutamate levels. Modified aspartate immunoreactivity began at postnatal day 11 and is consistent with altered metabolic activity. These results suggest that amino acid neurochemistry is different in the RCS rat retina from an early age, which may indicate an underlying metabolic defect affecting multiple cell classes. PMID- 9364236 TI - Botzinger neurons project towards bulbospinal neurons in the rostral ventrolateral medulla of the rat. AB - Sympathetic nerve activity often fluctuates with the respiratory cycle, but the central neurons that impose this respiratory modulation have not been conclusively identified. In the present study, we used intracellular recording and dye-filling to identify expiratory neurons in the Botzinger complex. Our aim was to see if Botzinger neurons project towards putative cardiovascular neurons in the rostral ventrolateral medulla. In the first series of experiments, histochemistry and immunohistochemistry were used to reveal the labelled Botzinger neurons and neurons immunoreactive for tyrosine hydroxylase. Two out of four Botzinger neurons had axon varicosities that were closely apposed to tyrosine hydroxylase-immunoreactive neurons with cell bodies located within 0.6 mm caudal to the facial nucleus (three and five close appositions, respectively). In a second series of studies, rats were injected with cholera toxin B into the intermediolateral cell column of the spinal cord 4-7 days before the electrophysiological recording. Eight of the fourteen labelled Botzinger neurons had a direct projection towards cholera toxin B-labelled neurons in the rostral ventrolateral medulla. Close appositions were found on both somata and proximal dendrites (5 +/- 2 close appositions/neuron, n = 8). The present study supports the idea that a direct projection from Botzinger neurons to presympathetic neurons in the rostral medulla plays a role in the respiratory modulation of sympathetic nerve activity. PMID- 9364237 TI - Nasotemporal asymmetries in V1: ocular dominance columns of infant, adult, and strabismic macaque monkeys. AB - To quantify asymmetries of input from the two eyes into each cerebral hemisphere, we measured ocular dominance column (ODC) widths and areas in the striate visual cortex (area V1) of macaque monkeys. Ocular dominance stripes in layer 4C were labeled by using transneuronal transport of intraocularly injected wheat germ agglutinin-horseradish peroxidase (WGA-HRP) or cytochrome oxidase (CO) histochemistry, after deafferentation of one eye or even by leaving afferent input intact. In infant monkey aged 4 and 8 weeks, ocular dominance stripes labeled by WGA-HRP appeared adultlike with smooth, sharply defined borders. In normal infant and normal adult macaque, ocular dominance stripes driven by the nasal retina (i.e., contralateral eye) were consistently wider than stripes driven by the temporal retina (i.e., ipsilateral eye). Asymmetries in the percentage of area V1 driven by nasal vs. temporal ODCs showed a similar "nasal bias": in infant macaque, approximately 58% of ODCs in V1 were driven by nasal retina, and in adult macaque approximately 57%. The asymmetries tended to be slightly smaller in opercular V1 and greater in calcarine V1. "Spontaneous" ocular dominance stripes were revealed by CO staining of V1 in a naturally strabismic monkey and in a monkey made strabismic by early postnatal alternating monocular occlusion. In these animals, ocular dominance stripes and CO blobs corresponding to the nasal retina stained more intensely for CO in both the right and left V1. ODC spacing and the nasotemporal asymmetry in ODC width and area were similar in strabismic and normal monkeys. Our results in normal monkeys extend the observations of previous investigators and verify that nasotemporal inputs to opercular and calcarine V1 are unequal, with a consistent bias favoring inputs from the nasal retina. The CO results in strabismic macaque suggest that the nasal ODC bias promotes interocular suppression when activity in neighboring ODCs is decorrelated by abnormal binocular experience in infancy. PMID- 9364238 TI - Migration and synaptogenesis of cone photoreceptors in the developing mouse retina. AB - Mouse retinal photoreceptor cell generation and morphogenesis take place in a well-characterized temporal sequence. Both rod and cone photoreceptor differentiation and synaptogenesis occur postnatally, but the relative timing of these events has been difficult to document due to the paucity of cell-specific markers. We have found that antibodies to neuron-specific enolase (NSE) preferentially label a subpopulation of photoreceptors in the outer nuclear layer (ONL) of the mouse retina in addition to labeling ganglion, amacrine, bipolar, and horizontal cells within the inner layers of the retina. The appearance of NSE immunoreactivity in the different classes of retinal neurons during development showed a close temporal relationship to the onset of expression of the synaptic vesicle-associated protein SV2 and clearly preceded the sequential development of synaptic connections in both inner and outer synaptic layers. The NSE immunoreactive photoreceptors were identified as cones by dual labeling of their inner segments with the lectin peanut agglutinin or by colabeling with antisera to cone photopigments. Axonal extensions of NSE-labeled cone cells were shown to interact with those of differentiating horizontal cells as early as postnatal day 3 (P3). Colocalization of NSE with SV2 indicated that cone cells began to make synaptic contacts with horizontal cell processes several days prior to the development of rod synaptic terminals. Between P4 and P11, cone photoreceptor cell nuclei were observed to be scattered at various levels throughout the ONL and thus appeared to have become displaced from their previous position directly beneath the outer limiting membrane (OLM). By P12, the cone nuclei had migrated sclerad once again and were now observed to be neatly aligned adjacent to the OLM. In the rd mouse mutant, this migratory process was delayed, so that, at P12, positioning of the cone cell nuclei within the ONL was still quite irregular. Thus, we have identified a late migratory phase for cone photoreceptors during the second week after birth that correlates with the timing of maturation of the rod synaptic terminals just prior to eye opening. The types of cues used by maturing cone cells for their eventual sclerad location remain to be elucidated. PMID- 9364239 TI - Distribution of parvalbumin-, calretinin-, and calbindin-D28k-immunoreactive neurons and fibers in the human entorhinal cortex. AB - Parvalbumin, calretinin, and calbindin-D28k are calcium-binding proteins that are located in largely nonoverlapping neuronal populations in the brain. The authors studied the distribution of parvalbumin-, calretinin-, and calbindin-D28k immunoreactive (ir) cells, fibers, terminals, and neuropil in the eight subfields of the human entorhinal cortex. The distribution of each of the three calcium binding proteins largely followed the cytoarchitectonic borders of the eight entorhinal subfields, although the regional and laminar distributions of the three proteins were segregated rather than overlapping. The highest density of parvalbumin-ir neurons and terminals was found in the caudal and lateral subfields of the entorhinal cortex. Calretinin and calbindin-D28k immunoreactivities were high rostromedially, although a large number of calretinin and calbindin-D28k neurons were also found in the caudal subfields. All parvalbumin-ir cells had a morphological appearance of nonpyramidal neurons. Parvalbumin-ir terminals formed basket-like formations around unstained somata and cartridges, suggesting that parvalbumin neurons compose a subpopulation of gamma-aminobutyric acid (GABA)ergic basket cells and chandelier cells, respectively. Although calretinin and calbindin-D28k were also found in numerous nonpyramidal neurons, both were also located in pyramidal-shaped neurons in layers V and VI (calretinin) and in layers II and III (calbindin) of the entorhinal cortex, suggesting that they play roles in projection neurons as well. Moreover, the high density of nonpyramidal neurons containing calcium-binding proteins in layers II and III of the entorhinal cortex suggests that they form an integral component of a network that controls the entorhinal outputs to the hippocampus. Furthermore, the largely nonoverlapping distributions of the parvalbumin-, calretinin-, and calbindin-ir neuronal populations in the entorhinal cortex indicate that each of them may modulate a different subset of topographically organized entorhinal outputs. PMID- 9364240 TI - Nitric oxide synthase in the adult and developing thalamus: histochemical and immunohistochemical study in the rat. AB - The distribution of neuronal elements that express nitric oxide synthase (NOS), the synthetic enzyme of the free radical nitric oxide, was investigated in the adult and developing rat thalamus by means of NADPH-diaphorase (NADPH-d) histochemistry, which is a marker of NOS. Immunocytochemistry was also used to confirm the equivalence between the histochemical pattern of staining and the distribution of the expression of the neuronal NOS isoform. In the adult thalamus, NADPH-d-positive and NOS-immunoreactive perikarya were selectively concentrated along the midline (in the paraventricular, rhomboid, and central medial nuclei) and in the dorsal and ventral lateral geniculate nuclei. Isolated clusters of stained neurons were also observed in the lateral posterior nucleus, in the dorsal part of the medial geniculate nucleus, and in the ventromedial nucleus. Positive perikarya were either absent or very sparse in the other thalamic nuclei. Many thalamic domains were, however, characterized by distinct patterns of NADPH-d-positive fibers, preterminal and terminal-like elements. The highest density of stained neuropil was observed in the anteroventral and anteromedial nuclei, in several of the midline nuclei, in the anterior intralaminar nuclei, and in the lateral and medial geniculate nuclei. Although histochemical reactivity was observed in the thalamus at birth, the intensity and the pattern of distribution of staining observed in adulthood was not achieved until the end of the third postnatal week. The NADPH-d histochemical positivity followed discrete developmental schedules in various thalamic domains, and different areas reached a mature pattern at different ages. In addition, populations of transiently stained neuronal cell bodies were observed in the medial thalamus during the first two postnatal weeks. These results show discrete patterns of expression of NOS in the adult and developing thalamus and suggest that nitric oxide may be involved in selected physiological and developmental roles in different thalamic domains. PMID- 9364241 TI - Exaggerated astrocyte reactivity after nigrostriatal deafferentation in the aged rat. AB - Although clinical experience suggests that brain injury in the aged is associated with a poor prognosis, little research has examined this phenomenon at a cellular or molecular level. Unilateral 6-hydroxydopamine lesions of the nigrostriatal system were produced in 6-, 15- or 24-month-old rats. In the deafferented neostriatum, the time-dependent induction of glial fibrillary acidic protein (GFAP) was larger and persisted longer in the aged rats. The response of middle aged rats was intermediate. In contrast, no induction of S-100 or glutamine synthetase was observed in any age group. In a second series of rats with stab wounds in the neostriatum, there were substantially larger GFAP inductions than after deafferentation, but fewer effects of age. However, in both lesion paradigms, GFAP staining increased in the contralateral striatum of old rats, but not in young rats. These data support and extend our earlier work describing larger GFAP RNA inductions after fornix transections in aged mouse hippocampus. The consistency of this exaggerated glial reactivity in the aged brain after modest injury suggests the following: 1) aged astrocytes are more sensitive to gliotrophic factors released by terminal degeneration, 2) larger quantities of such factors are produced after injury, 3) clearance of these factors is delayed in old rodents, and/or 4) aged astrocytes are less able to terminate GFAP inductions after activation. Given the potential role of inflammatory reactions as pathogenic mechanisms in Alzheimer's dementia, these data suggest that age related glial hypersensitivity may independently increase the risk for some degenerative diseases. PMID- 9364242 TI - Distribution of neurons immunoreactive for parvalbumin and calbindin in the somatosensory thalamus of the raccoon. AB - The aim of this study was to assess the distribution of neurons immunoreactive for parvalbumin (PV), calbindin (CaBP), glutamic acid decarboxylase (GAD), and gamma-aminobutyric acid (GABA) in the somatosensory thalamus of the raccoon and to compare these features to those of other species, especially primates. Immunohistochemistry was used to study the location of these neurons in the ventroposterior nucleus (VP), ventroposterior inferior nucleus (VPI), posterior group of nuclei (Po), and reticular nucleus (Rt). A consistent differential pattern of PV-positive (PV+) and CaBP-positive (CaBP+) cells was found in the somatosensory thalamus. Many PV+ neurons were observed in VP and Rt, but very few were found in VPI or Po. In contrast, CaBP+ neurons were distributed throughout VP, VPI, and Po but were very sparse or absent in Rt. In the VP nucleus, PV+ cells were distributed in clusters separated by interclusteral regions with a sparse distribution of PV+ cell bodies. The distributions of PV+ and CaBP+ cells tended to be complementary to each other in VP; regions with a high density of PV+ neurons had a low density of CaBP+ cell bodies. Double-labeling experiments revealed very few neurons in which PV and CaBP immunoreactivities were colocalized. Cells immunoreactive for GAD or GABA were found in PV-dense clusters of VP; fewer GABAergic neurons were present in the CaBP-dense interclusteral regions of VP and in VPI and Po. GAD+ and GABA+ neurons were most prominently distributed in Rt. We conclude that the distributions of PV+ and CaBP+ cell bodies in the raccoon somatosensory thalamus are very similar to those in primates. The density of GABAergic neurons in the somatosensory thalamus of the raccoon is less than that in the cat and monkey, but the relative distribution of GABAergic neurons in the different somatosensory nuclei is very similar to that in the cat and monkey. These results are discussed in relation to findings in other species and are related to the functions of lemniscal and nonlemniscal somatosensory pathways. PMID- 9364243 TI - Distribution of muscarinic cholinergic receptor proteins m1 to m4 in area 17 of normal and monocularly deprived rhesus monkeys. AB - Antibodies to muscarinic cholinergic receptor proteins m1 to m4 were used in striate cortex tissue of normal rhesus monkeys to determine the laminar distribution of these proteins with special attention to geniculorecipient layers. The normal patterns were compared to those of monkeys whose ocular dominance system had been altered by visual deprivation. In normal monkeys, immunoreactivity of all four proteins was localized in complex laminar patterns; m1 was densest in layers 2, 3, and 6, followed by layer 5. In contrast, m2 reactivity was densest in lower layer 4C and in 4A; the latter exhibited a honeycomb pattern. Layers 2 and 3 displayed alternating dense and light regions; this pattern was complementary to that of cytochrome oxidase (CytOx). Laminar immunoreactivity for the m3 receptor was similar to the CytOx pattern, including a honeycomb in 4A and a pattern of alternating darker and lighter patches in layers 2/3. Antibody to m4 reacted most densely with layers 1, 2, 3, and 5, layers 2 and 3 exhibited alternating dark and light regions, and layer 4A had a faint honeycomb. Layer 4C was the lightest band. The differential distribution of these four muscarinic receptor subtypes suggests distinct roles in cholinergic modulation of visual processing in the primate striate cortex. Furthermore, all four muscarinic receptors appear to be insensitive to elimination of visual input via monocular occlusion from birth, to deprivation of pattern vision in one eye during a specific time period in adulthood, and to long-term retinal injury. PMID- 9364244 TI - Localization of dopamine D1 receptors and dopaminoceptive neurons in the chick forebrain. AB - The distributions of dopamine D1 receptors, dopaminoceptive neurons, and catecholaminergic fibers were investigated in the forebrain of the domestic chick by using D1 receptor autoradiography and immunohistochemical detection of D1 receptor protein (D1rp), the dopamine- and cAMP-regulated phosphoprotein DARPP 32, and tyrosine hydroxylase (TH). Particular attention was paid to two forebrain regions, the mediorostral neostriatum/ hyperstriatum ventrale (MNH) and neostriatum dorsocaudale (Ndc), which have been shown to be crucially involved in filial imprinting. In general, there was a good, but not complete, correlation between the immunohistochemical pattern of DARPP-32 positive perikarya and the distribution of D1 receptors. Both, DARPP-32 positive neurons as well as D1 receptors were highly enriched in the striatal part of the basal ganglia including the lobus parolfactorius (LPO) and paleostriatum augmentatum. High to moderate densities were observed in the outer rind of the pallium. Low to moderate densities were found in the belt regions of primary sensory areas, whereas densities in the respective core regions were generally low. Labeling in the MNH and Ndc was heterogeneous. Whereas the neostriatal part of MNH displayed both, moderate DARPP-32 immunostaining and moderate D1 receptor densities, the hyperstriatal part showed also moderate D1 receptor densities but was only weakly labeled by DARPP-32. The rostral part of the Ndc was among the most intensely DARPP-32 labeled areas of the pallium, its caudal part revealed only moderate DARPP-32 immunostaining. By using D1 receptor autoradiography, a homogeneous labeling throughout the rostrocaudal extension of the Ndc was found. Double labeling experiments with antibodies to DARPP-32 and TH revealed that TH positive fibers in the MNH, Ndc, and LPO were often closely related to DARPP-32 positive perikarya. At the ultrastructural level, both immunoreaction for D1rp and DARPP 32 in the MNH and Ndc were primarily found to be associated with postsynaptic elements. Whereas D1rp immunoreactivity was enriched at postsynaptic densities or in their vicinity, reaction product for DARPP-32 was present throughout the perikaryal cytoplasm, dendrites, and dendritic spines. These results indicate that DARPP-32 as well as D1 receptors in the avian forebrain reveal a distribution that is substantially similar to that of mammals. PMID- 9364245 TI - Long-term effects of octreotide on markers of bone metabolism in acromegaly: evidence of increased serum parathormone concentrations. AB - The effects of octreotide on biochemical markers of bone turnover were evaluated in patients with active acromegaly. Serum GH, IGF-I and serum and urinary markers of bone metabolism were measured before and after 4 months of treatment in 27 patients (short-term treatment) and after 12 and 24 months of treatment in 15 patients (long-term treatment). In the short-term, octreotide significantly decreased the levels of serum GH, IGF-I, calcium, osteocalcin, carboxyterminal propeptide of type I collagen and alkaline phosphatase plus urinary excretion of calcium. Short-term treatment significantly increased serum parathormone levels (before treatment 30.1 +/- 9.57 and at 4 months 46.1 +/- 24.98 ng/L, p < 0.001) and urinary excretion of phosphate; urinary excretion of hydroxyproline was unchanged. The same results were observed during long-term treatment, except that there was no significant difference of serum calcium and alkaline phosphatase levels before and after treatment. Parathormone concentrations were still higher at 24 months compared with those prior to treatment (before treatment 31.9 +/- 9.74 and at 24 months 44.9 +/- 21.18 ng/L, p < 0.05). The changes of most bone markers during octreotide therapy can be explained by the decrease of serum GH and IGF-I concentrations. On the other hand, the rise of parathormone concentrations suggests that octreotide has ulterior and long-standing actions on calcium homeostasis: intestinal malabsorption of calcium due to the octreotide could contribute to this secondary hyperparathyroidism. The clinical consequences of these alterations of bone metabolism need to be further clarified. PMID- 9364246 TI - Puberty influences expression of phospholipid hydroperoxide glutathione peroxidase (GPX4) in rat testis: probable hypophysis regulation of the enzyme in male reproductive tract. AB - Mammalian spermatozoa are unusually rich in polyunsaturated fatty acids, a property that predisposes them to the deleterious effects of oxygen free radicals. Mouse and human spermatozoa utilize glutathione peroxidase, (GPX), to inactivate oxygen free radicals. In the GPX super-family there is the enzyme phospholipid hydroperoxide glutathione peroxidase (GPX4) that specifically protects membrane phospholipids against peroxidation. GPX4 is present, primarily, in testis where its enzymatic activity seems to be present only after puberty. In order to clarify this question we utilized total RNA from rat testis, liver and lung to carry out cDNA synthesis and the following RT-PCR amplification of cDNA products by using specific primers of rat liver sequence. RT-PCR products of the expected size for GPX4 (525 bp) were obtained from the three tissues. At last, these fragments were submitted to sequencing analysis. Here we demonstrate that the sequence analysis of rat testis GPX4 coding region is identical to that of rat liver and lung; however puberty influences the expression pattern of rat testis GPX4. In fact Northern blot analysis of total RNA from normal and pre puberal hypophysectomized rats demonstrates the absence of a specific GPX4 mRNA in total RNA from pre-puberal hypophysectomized rat testis; on the other hand this specific transcript is present in both normal rat testis and liver and in pre-puberal hypophysectomized rat liver. Expression pattern of GPX4 is very low in lung both in post-puberal and pre-puberal hypophysectomized rats. Therefore hypophysis could regulate GPX4 transcript in rat testis. PMID- 9364247 TI - Effects of tamoxifen on GH and IGF-I levels in acromegaly. AB - Tamoxifen (TAM), a non steroid partially competitive antagonist to the estrogen receptors, has been reported to decrease plasma GH and IGF-I levels both in vitro and in vivo. These data prompted us to evaluate GH and IGF-I changes in acromegaly after acute and chronic TAM administration. Nineteen acromegalic patients (6 M, 13 F, aged 30-70 years) were studied in a prospective open study. Acute TAM test (20 mg po) did not induce any significant change in GH and IGF-I levels. Chronic TAM treatment (20 mg/day for a month and 40 mg/day for another month) induced a transient increase in GH levels (from 9 [3-139] micrograms/l [median, range] to 12 [3-188] micrograms/l, p = 0.0025) and a persistent decrease in IGF-I levels (from 785 [500-1200] micrograms/l to 553 [209-1420] micrograms/l, p = 0.0034). Individual IGF-I values decreased in 13 patients and reached the normal range in 4 of them. At TAM withdrawal hormonal levels increased up to pretreatment values. There was no correlation between GH and IGF-I changes and results were not influenced by age, sex or gonadal status. In this setting it is likely that the observed decrease in plasma IGF-I levels is dependent on TAM activity at the hepatic level. PMID- 9364248 TI - Thyroid-stimulating antibody and TSH-binding inhibitor immunoglobulin in 277 Graves' patients and in 686 normal subjects. AB - TSH receptor antibodies (TRAb) are believed to cause hyperthyroidism of Graves' disease. Thyroid-stimulating antibody (TSAb) and TSH-binding inhibitor immunoglobulin (TBII) have been measured as TRAb to diagnose Graves' disease and to follow Graves' patients. We intended to evaluate the clinical value of TRAb (TSAb and TBII) assay in establishing the diagnosis of Graves' disease and in predicting its clinical course. TSAb and TBII were studied in 686 normal subjects and in 277 Graves' patients before antithyroid drug therapy. We followed serial changes of TSAb and TBII in 30 Graves' patients before, during and after antithyroid drug therapy over 3.5-9 yr. We measured TSAb as a stimulator assay and TBII as a receptor assay. Both TSAb and TBII were distributed normally in 686 normal subjects. ROC curves demonstrated that both TSAb and TBII had high sensitivity and specificity for the diagnosis of Graves' disease, and were equally sensitive and specific; 150% was chosen as cut-off value for TSAb and 10% for TBII. Of the 277 untreated Graves' patients, 254 (92%) had positive TSAb and positive TBII. All of the 277 untreated Graves' patients had positive TRAb (TSAb and/or TBII). We followed the serial changes of TSAb and TBII in 30 Graves' patients over 3.5-9 yr. During antithyroid drug therapy, TSAb and TBII activities decreased and disappeared in 27 patients (Group A), but continued to be high in the other 3 (Group B). The former 27 Group A patients achieved remission, but the latter 3 Group B patients continued to have hyperthyroidism. Of the 27 Group A patients, 16 (59%) had parallel decreases of TSAb and TBII activities; in 6, the changes were predominantly observed in either TSAb or TBII, and in 4, complex changes in TSAb and TBII activities were observed. Disappearance of TSAb and appearance of TSBAb was seen in one. The other 3 Group B patients continued to have high TSAb and TBII activities and to have hyperthyroidism. In conclusion, TSAb and TBII are of clinical value in establishing the diagnosis of Graves' disease and in predicting its clinical course. We clearly demonstrated its diagnostic usefulness. Both TSAb and TBII have high sensitivity and specificity. All of the 277 untreated Graves' patients had TRAb (TSAb and/or TBII). Serial changes of TSAb and TBII during therapy differ from one patient to another, and can be classified into several groups. Changes in TSAb and TBII activities reflect the clinical courses of Graves' patients. The simultaneous measurement of both TSAb and TBII is clinically useful, since TSAb and TBII reflect two different aspects of TRAb. TSAb and TBII are different. PMID- 9364249 TI - Hypothalamic-pituitary axis dysfunction in critically ill patients with a low free thyroxine index. AB - The purpose of this study is to investigate the association of hypothalamic pituitary axis abnormalities with the free thyroxine index (FTI) in critically ill patients. Fourteen critically ill patients and twenty healthy volunteers were studied using combined anterior pituitary gland testing with CRF, GHRH, TRH, and GnRH. The subjects were grouped as follows: I-healthy volunteers; II-sick/normal FTI; and III-sick/low FTI. Serial measurements of hormones were performed over a two-hour interval and the following parameters were measured: baseline level, response amplitude and time to maximal response. Response velocities and area under-the-curves (integrated responses) were also computed. Group III had a longer mean ICU duration prior to testing than group II. Urinary cortisol, serum cortisol and serum PRL levels were elevated in groups II and III. However, group III had lower baseline ACTH levels, slower ACTH and TSH response velocities and decreased PRL integrated responses. Cortisol response parameters were similar between groups II and III. There were no differences in LH, FSH or GH response velocities or integrated responses among the 3 groups. These data confirm that critically ill patients develop hyperprolactinemia and hypothalamic-pituitary adrenal axis activation but when a low FTI exists, a plurality of changes occur reflected by attenuated PRL, TSH and ACTH responses despite unaffected adrenal cortisol output. PMID- 9364250 TI - The erythrocyte glutathione levels during oral glucose tolerance test. AB - Erythrocytes glutathione (GSH) levels were measured in erythrocytes from 33 subjects, at baseline and after 2-hour glucose loading in order to investigate the effect of glucose ingestion on the erythrocyte GSH. According to the World Health Organisation criteria 18 subjects had normal glucose tolerance (NGT)(mean age 48 +/- 10 years, 10 women, 8 men), 15 subjects had impaired glucose tolerance (IGT)(mean age 52 +/- 8 years, 9 women, 6 men). After 12-hour fasting, erythrocyte GSH levels were 40.5 +/- 8.06 and 39.27 +/- 10.26 mg/dl hemolisate in subjects with NGT and IGT, respectively (p = N.S). After 2-hour glucose loading, erythrocyte GSH levels decreased to 36.01 +/- 9.4 (p < 0.05) and 32.36 +/- 5.7 (p < 0.005) in subjects with NGT and IGT, respectively. The decrease in erythrocyte GSH levels in subjects with IGT was greater than in NGT individuals (p < 0.001). There was negative correlation between glucose, insulin, C-peptide, and erythrocyte GSH levels after glucose loading (p < 0.005). Our results suggest that glucose loading induce an oxidative stress in all subjects but this oxidative stress is greater in subjects with IGT than with NGT. PMID- 9364251 TI - Blunted cortisol response after administration of corticotropin releasing hormone in endotoxemic dogs. AB - To evaluate the effects of a standard inflammatory challenge on the dynamics of the hypothalamic-pituitary-adrenal (HPA) axis, we studied the effects of low-dose endotoxin (1.0 microgram/kg) on plasma adrenocorticotropic hormone (ACTH) and cortisol concentrations in a saline-controlled study in five awake dogs. Four hours after endotoxin or saline challenge human corticotrophin-releasing hormone (hCRH; 1.0 microgram/kg) was administered. Plasma ACTH and cortisol levels increased considerably in response to endotoxin, from 13 +/- 1 ng/l to 360 +/- 85 ng/l (p < 0.01) and from 60 +/- 20 nmol/l to 710 +/- 80 nmol/l (p < 0.01). Despite a considerable difference in ACTH and cortisol levels prior to CRH administration between both studies (p < 0.01), the absolute increase in ACTH levels induced by hCRH was not different (231 +/ 43 ng/l vs 238 +/- 45 ng/l, control vs endotoxin). Plasma cortisol levels increased significantly in the control study (from 40 +/- 10 nmol/l to 330 +/- 40 nmol/l, p < 0.01), whereas they did not change in the endotoxin study after hCRH administration (from 710 +/ 80 nmol/l to 730 +/- 70 nmol/l, ns). We conclude that the HPA-axis reacts initially to endotoxin in such a way that cortisol, but not ACTH, secretion is maximized. Therefore, a blunted cortisol response to CRH testing is part of the initial response to infection. PMID- 9364252 TI - Fine-needle aspiration biopsy of thyroid nodules: impact on clinical practice. AB - The aim of the present study was to analyze the changes in our clinical practice due to the use of FNAB in the management of nodular thyroid disease. Patients attended the thyroid unit for thyroid nodules. The study comprises three periods: First, from January 1980 to May 1984, 226 patient. Second, from June 1985 to December 1990, 166 patients. Third, from January 1991 to December 1993, 403 patients. DESIGN: retrospective the 1st period and prospective the 2nd and 3rd periods. During the 1st and 2nd periods, decision for surgery was based on clinical parameters together with results of 99Tc radionucleotide scan and B mode ultrasound studies. In the 3rd period surgical decision was based principally on cytologic results. We comparatively studied the frequency of surgical operation and frequency of malignancy in surgical thyroid specimens between the study periods. Determination of sensitivity, specificity and accuracy of the diagnostic methods was done. We observed a decrease in the frequency of patients requiring surgery, 89.9%, 67.8% and 46.6% for the 1st, 2nd and 3rd study periods, X2 = 114.7, p < 0.0001; and an increase in the frequency of malignancy in the surgical specimens, 14.7%, 24.4% and 32.9% for 1st, 2nd and 3rd periods respectively, X2 = 4.5, p < 0.05. The sensitivity 92.5% and 93.5%, the specificity 50.6% and 61.1%, and the accuracy 60.9% and 71.8% of the FNAB for the second and third periods respectively. The rates of false negative cytological specimens were 1.8% and 2.1% for 2nd and 3rd respectively, p > 0.05. Since the introduction of FNAB in the evaluation of our patients around 70% of these had a definitive preoperative diagnosis of either benign or malignant disease. Simplification in management of patients with nodular thyroid disease is the most important impact for the use of FNAB. Furthermore, a decrease in the number of patients requiring surgical treatment and an increase of malignant nodules in the specimens obtained by surgery were also observed. We think that FNAB is the most direct and accurate method in the management of patients with thyroid nodules. PMID- 9364253 TI - Comparison among the effects of arginine, a nitric oxide precursor, isosorbide dinitrate and molsidomine, two nitric oxide donors, on hormonal secretions and blood pressure in man. AB - Arginine has well-known stimulatory effects on GH, PRL and insulin secretion in man but the mechanisms underlying these effects are still unclear. More recently, it has been demonstrated that arginine is the precursor of nitric oxide (NO) which mediates its vasodilatatory effect. Thus, it has been hypothesized that NO could also mediate the hormonal effects of arginine. To clarify this point, in seven normal young volunteers (7 normal male subjects, age 26-35 yr) we compared the effects of arginine hydrochloride (ARG, 0.5 g/kg iv over 30 min) on GH, PRL, insulin and glucose levels as well as on blood pressure, with those of isosorbide dinitrate (ISDN, 5 mg po) and molsidomine (MOLS, 4 mg po), two NO donors which possess well-known vasodilatatory effects. ARG infusion elicited a clear-cut GH increase (peak vs baseline 17.6 +/- 4.7 vs 2.7 +/- 0.8 (g/L, p < 0.01), PRL (20.6 +/- 2.8 vs 6.9 +/- 0.5 (g/L, p < 0.01) and insulin levels (31.4 +/- 5.7 vs 4.5 +/ 2.1 (U/L, p < 0.01) while induced a biphasic variation of plasma glucose levels with early increase (p < 0.01), followed by late decrease below basal values (p < 0.01). On the other hand, blood pressure was decreased by ARG (nadir vs baseline; systolic: 103 +/- 6 vs 112 +/- 3, p < 0.02 and diastolic 61 +/- 4 vs 72 +/- 2 mmHg, p < 0.02, respectively). ISDN and MOLS did not modify basal GH, PRL and insulin as well as glucose levels while induced a clear reduction in blood pressure (ISDN: nadir vs baseline; systolic: 94 +/- 4 vs 112 +/- 2, p < 0.02; diastolic 69 +/- 3 vs 80 +/- 2, p < 0.02; MOLS: systolic: 94 +/- 3 vs 113 +/- 2 p < 0.02; diastolic 63 +/- 4 vs 72 +/- 2, p < 0.02). The lowering effect of both ISDN and MOLS on both systolic and diastolic blood pressure levels was higher than that induced by ARG. The effect of the latter was, in turn, significantly different from that of placebo on diastolic levels only. In conclusion, our present date are against the hypothesis that NO mediates the stimulatory effects of arginine on GH, PRL and insulin secretion. On the other hand, our findings agree with the hypothesis that ARG has NO-mediated vasodilatatory effect able to decrease blood pressure in man. PMID- 9364255 TI - Pituitary apoplexy developed in a patient with androgen insensitivity syndrome. AB - At the age of 18, our patient was diagnosed as complete androgen insensitivity syndrome(AIS) based on androgen receptor studies in cultured genital skin fibroblasts. Compatible with this diagnosis, both testosterone and LH levels in her plasma were elevated as compared to levels in normal females. Later, the patient had been uneventful until she sought medical attention for headache at the age of 38. Magnetic resonance imaging (MRI) of the brain pointed to pituitary apoplexy. Since her symptoms were not alleviated by conservative therapy, neurosurgical decompression via a transsphenoidal approach was performed. A histopathological examination of a surgical specimen revealed that the pituitary hemorrhage occurred in an LH-producing adenoma. It is likely that the adenoma developed from gonadotroph hyperplasia which could exist in the AIS pituitary. It may be worth noting that this patient has never had a chance of receiving hormonal replacement therapy with estrogen and progesterone. Considering the fact that the majority of AIS patients are treated with gonadal steroids and such a treatment reestablishes an appropriate negative feedback on enhanced LH secretion, it is possible that the lack of hormonal therapy in our patient may have served as a precipitating factor for the apoplectic episode. Although we are not aware of any documented case report of pituitary apoplexy developed in AIS, such a pituitary emergency should be born in mind in the long-term follow-up of patients with AIS. In addition, it is also suggested that the hormonal replacement therapy with gonadal steroids may be recommended for AIS patients not only to endow them with physical characteristics as a woman but also to prevent the development of gonadotroph hyperplasia and possibly also of LH-producing adenoma in the pituitary. PMID- 9364254 TI - Gonadotropin-releasing hormone agonists administration in polycystic ovary syndrome. Effects on bone mass. AB - Women with amenorrhea and polycystic ovaries (PCO) seem to present a relative degree of protection against bone loss caused by hypoestrogenism. We treated 20 patients affected by polycystic ovary syndrome (PCOS) with a gonadotropin releasing hormone agonist (GnRH-a) for 6 months. After treatment mean bone mineral density (BMD) significantly decreased. We concluded that patients with PCOS have to be considered at risk of developing osteopenia when treated with GnRH-a. The relative protection against osteoporosis, that is present in amenorrheic patients with PCO, might be attributed to the characteristics of amenorrhea in these patients. PMID- 9364256 TI - Pre-Cushing's syndrome not recognized by conventional dexamethasone suppression tests in an adrenal "incidentaloma" patient. AB - Pre-Cushing's syndrome has been recently diagnosed in 6-12% of patients affected with incidentally discovered adrenal masses. Some of these patients have been described to show transient hypoadrenalism after surgery, similarly to those affected with overt Cushing's syndrome. We studied a 70-year-old male patient with a large left adrenal mass, incidentally discovered, who displayed 24-h urinary free cortisol levels at the upper limit of the normal range, normal dexamethasone overnight and low-dose suppression tests and not suppressed ACTH levels, increased 17-hydroxyprogesterone response to ACTH stimulation and low upright plasma renin activity with normal serum aldosterone levels; furthermore, DHEAS level was low and 75 Selenium-cholesterol scintigraphy showed unilateral uptake concordant with the side of the mass. Soon after left adrenalectomy, he complained of acute hypoadrenalism requiring cortisol replacement therapy: ten months after surgery he is still hypoadrenal. Moreover, stimulated 17 hydroxyprogesterone and plasma renin activity in clino- and orthostatic posture have become normal. We propose that conventional dexamethasone suppression-tests may be not enough sensitive in this kind of patients and that in selected cases the absence of controlateral uptake at scintigraphy may be more reliable in predicting post-surgical hypoadrenalism. PMID- 9364257 TI - National surveillance of hospital-acquired infection--can performance indicators be developed? PMID- 9364258 TI - Epidemiology of vancomycin-resistant enterococci in the community and the relevance of farm animals to human infection. AB - Several reports have documented the presence of vancomycin-resistant enterococci (VRE) in the stools of asymptomatic individuals from the community who have neither recently been in hospital nor received antibiotics. Such findings were contrary to the then existing perception of VRE as a strictly hospital-acquired infection of debilitated and immunocompromised patients on specialized units. Community-acquired infections with VRE are extremely rare but those that do occur may be conspicuous because of their serious nature, for example, endocarditis. If asymptomatic faecal carriage of VRE is present in the community, individuals admitted to hospital and subjected to the selective pressures of antibiotics on the normal gut flora, may act as the source of hospital outbreaks. VRE have also been found in sewage, from stools of healthy farm animals and animal products. Avoparcin, a glycopeptide showing cross-resistance to medically important glycopeptides, has been used in the European Community as a growth promoter in animal feeds. A possible link between the use of avoparcin, the selection of VRE, and humans becoming colonized via the food chain exists. To prove such a link is beset with many difficulties: it is necessary to explain the presence of VRE in the United States where avoparcin is not used, and the predominance of the VanA gene over the VanB gene. It is also proving difficult to show that animal and human strains are identical by means of molecular typing. To date, molecular typing of strains is only suggestive of a link, but epidemiological studies of farms that use avoparcin have shown a significant association with the presence of VRE in animal stools. As long ago as 1969, the Swann report declared that an antibiotic of medical importance should not be used as a growth promoter in animal feeds. The vasy array of antibiotics now being used in animal husbandry and fish-farming, and the cross-resistance of some antibiotics to their medically important counterparts is a real cause for concern. The emergence of multi resistant enterococci causing human infections and the possibility of the transfer of the VanA gene from VRE to methicillin-resistant Staphylococcus aureus (MRSA) emphasizes the importance of this problem. PMID- 9364259 TI - Analysis of risk factors for nosocomial infections--results from the first national prevalence survey in Germany (NIDEP Study, Part 1). AB - An analysis of risk factors for nosocomial infections (NI) was carried out using data from the first national prevalence survey on NI in Germany. Fourteen thousand, nine hundred and sixty-six patients, with a total of 543 NI, were included. Urinary tract infections (UTI), lower respiratory tract infections (LRTI), surgical site infections (SSI) and primary septicaemia (PS) were analysed. UTI were significantly associated with unconsciousness, age, prior operation, hospital size and female sex (P < 0.1). LRTI were significantly associated with chronic airway disease, intensive care units, unconsciousness, polytrauma, prior operation, cardiovascular disease, malignancy and absence of infection on admission. The department, age, diabetes mellitus, male sex and hospital size were risk factors for SSI. The department, prior operation and unconsciousness were significantly associated with PS. An investigator effect was observed for LRTI and PS. Although no final conclusions from a risk factor analysis based on prevalence data can be drawn the results support stratification of NI for routine surveillance. PMID- 9364260 TI - Nosocomial outbreak of multi-resistant Acinetobacter baumannii on a surgical ward: epidemiology and risk factors for acquisition. AB - Between December 1994 and April 1995, a nosocomial outbreak caused by a multi resistant Acinetobacter baumannii, occurred on a surgical ward in our hospital. The organism was isolated from 13 patients, eight of whom were infected whereas the others were colonized. Twelve isolates were compared by cell envelope protein electrophoretic profiles and AFLP, a recently described DNA fingerprinting method. Both methods indicated that this outbreak was caused by spread of a single strain, which was identified as A. baumannii by amplified ribosomal DNA fingerprinting (ARDRA). A case-control comparison was performed to identify risk factors associated with nosocomial acquisition of A. baumannii. Risk factors for cross-colonization were length of stay, surgery, wounds and treatment with broad spectrum antibiotics. Cross-infection with A. baumannii among patients occurred despite implementation of stringent infection control measures. The outbreak was controlled after temporary closure of the surgical ward for disinfection purposes. Patients admitted on a general surgical ward colonized or infected with multi-resistant A. baumannii strains should alert the hospital infection control team, and prompt implementation of strict infection prevention measures to prevent further spread is advised. PMID- 9364261 TI - Genotypic investigation of multidrug-resistant Acinetobacter baumannii infections in a medical intensive care unit. AB - Multi-resistant Acinetobacter baumannii isolates obtained from 13 hospitalized patients over a six-month period were evaluated. One patient had an isolate susceptible only to imipenem; the next three had isolates susceptible to imipenem and ampicillin/sulbactam; the next six patients had isolates which were susceptible to imipenem, amikacin, and ampicillin/sulbactam; while the final three patients had isolates which were susceptible to imipenem and ampicillin/sulbactam. Ten patients died, five within 10 days of a positive culture. Five of six patients with bacteraemia succumbed to the infection. DNA extracted from all isolates was amplified by polymerase chain reaction using four random primers (RAPD). The resulting band patterns were compared and strains identified. In addition, all isolates were biotyped. RAPD analysis and biotyping showed that there were two distinct strains involved. The first four patients were infected with one strain (genotype ?A', biotype 9), the subsequent nine patients were infected with a second strain (genotype ?B', biotype 1). These results suggested that there was patient-to-patient spread of strains. Institution of, and strict adherence to, isolation procedure and other infection control practices controlled the spread of infection. These data emphasize the need for active surveillance for multidrug-resistant organisms in critically ill patients, and the value of molecular typing of strains in a hospital setting to investigate spread of infection. PMID- 9364262 TI - Disinfection of bronchoscopes, contaminated in vitro with Mycobacterium tuberculosis, Mycobacterium avium-intracellulare and Mycobacterium chelonae in sputum, using stabilized, buffered peracetic acid solution ('Nu-Cidex'). AB - The efficacy of 0.35% stabilized buffered peracetic acid solution ('Nu-Cidex') against clinical isolates of Mycobacterium tuberculosis, Mycobacterium avium intracellulare and Mycobacterium chelonae in homogenized sputum was tested. An in use method, using an automated bronchoscope washing machine, showed that over 10 cycles, at a disinfectant contact time of 5 min, M. tuberculosis and M. chelonae were effectively eradicated from the bronchoscope, even in the absence of detergent and pre-cleaning. M. avium-intracellulare was not eradicated in only one of 10 cycles with contact times of 5 and 10 min, but numbers were reduced by > 7 log10 and > 5 log10, respectively. With detergent present, M. avium intracellulare was successfully eradicated in all cycles at a contact time of 5 min or greater. The results demonstrate that peracetic acid is an effective mycobactericidal agent for use in the disinfection of bronchoscopes. PMID- 9364263 TI - Evaluation of chlorhexidine and silver-sulfadiazine impregnated central venous catheters for the prevention of bloodstream infection in leukaemic patients: a randomized controlled trial. AB - It has been suggested that central venous catheters impregnated with antiseptics such as chlohexidine and silver-sulfadiazine reduce the risk of catheter-related bacteraemia in intensive care patients. Patients suffering from haematologic malignancy treated by chemotherapy through a central venous catheter are at even greater risk of catheter-related bacteraemia. A prospective double-blind randomized controlled trial was performed in order to investigate the effectiveness of chlorhexidine and silver-sulfadiazine impregnated catheters (CH SS) in these patients. A total of 680 catheters (13,826 catheter days) were inserted, of which 338 were antiseptic impregnated. Bloodstream infection was observed in 105 cases with an overall risk of 7.6 per 1000 catheter days. Thirty two infections (30.5%) were catheter-related, corresponding to a risk of 2.3 per 1000 catheter days. There was no statistically significant different between the overall rates of bloodstream infection for impregnated and non-impregnated catheters (14.5 vs. 16.3%). The incidence of catheter-related infection was also similar in both groups (5 vs. 4.4%) and there was no difference in the time of the onset of bacteraemia in the two groups. It is concluded that the use of CH-SS catheters in patients with haematologic malignancy reduces neither the overall risk of bloodstream infection, nor the catheter-related infection rate, nor the delay for the occurrence of infection. PMID- 9364264 TI - Chlorhexidine gluconate (CHG) activity against clinical isolates of vancomycin resistant Enterococcus faecium (VREF) and the effects of moisturizing agents on CHG residue accumulation on the skin. AB - The effectiveness of skin decontamination by chlorhexidine gluconate (CHG) in the presence of commonly-used skin moisturizing lotions was evaluated using vancomycin-resistant Enterococcus faecium (VREF) as a representative nosocomial pathogen. Anti-bacterial efficacy was determined in vitro using pigskin preparations inoculated with five VREF clinical isolates to evaluate Calgon Vestal 2 and 4% (by weight) CHG solutions in comparison with Hibiclens Antiseptic Antimicrobial Cleaner (4% CHG solution). Control inocula were determined for each experiment from recovery of VREF harvested directly from the surface of each control piece of skin. These CHG formulations were evaluated in the presence and absence of Calgon Vestal 'Lotion Soft Skin Conditioner' (LSSC) to determine potential interactions of CHG with LSSC, and also with ?Vaseline Intensive Care' lotion as a CHG-deactivating agent. The 2% Calgon Vestal CHG alone reduced VREF 10(2)-10(3)-fold, as well as 10(3)-10(4)-fold when LSSC was present, and was as efficacious as either 4% CHG solution when these were tested in the presence of LSSC. Four percent Calgon Vestal CHG produced reductions of 10(3)-10(5)-fold with or without LSSC present. Conversely, ?Hibiclens' showed similar reductions in the presence of LSSC to that for the Calgon Vestal 4% CHG, but only a 10(1)-10(3) fold reduction without LSSC. ?Vaseline Intensive Care' lotion completely inactivated the VREF-killing effects for all of the CHG formulations tested, while LSSC and ?Vaseline Intensive Care' lotion both showed minimal activity alone against these VREF isolates. These results indicate that the Calgon Vestal 2% CHG solution is as effective against VREF, even in the presence of LSSC, as either the 4% Calgon Vestal or Hibiclens 4% CHG formulations; the use of this lower concentration of CHG may be associated with less irritation, particularly with concomitant use of LSSC. PMID- 9364265 TI - Control of Legionella in a hospital potable water supply. PMID- 9364266 TI - Control of Legionella in a hospital potable water supply. PMID- 9364267 TI - MRSA pathogenicity and bacteraemia. PMID- 9364268 TI - Why are nurses under-recognised in the world of hypertension? PMID- 9364269 TI - The role of nurses in hypertension care and research. PMID- 9364270 TI - Genetics of stroke. AB - Stroke is a very common cause of death and disability. Several lines of evidence point to stroke as a polygenic multifactoral phenotype and there are also a number of well studied single gene Mendelian stroke conditions. Rat models have identified several chromosomal sites linked to stroke, and this together with other background information provides a strategy for both cross-sectional and gene scanning approach to defining the genetics of human stroke. PMID- 9364271 TI - New insights into cardiac excitation-contraction coupling in normal and hypertension/failure animal models. AB - Application of the confocal microscope to enzymatically isolated cardiac myocytes has revealed that excitation-contraction coupling is a ?local control phenomenon'. The whole cell calcium transient is made up of the temporal and spatial summation of a large number of microscopic calcium release events called ?calcium sparks'. The opening of a single calcium channel in the surface membrane can activate a calcium spark and there is a non-linear relationship between the amplitude of the single calcium channel flux and the probability of activating a calcium spark (Ps). Mathematical modelling shows that the relationship between surface membrane calcium channel gating and the activation of calcium release channels in internal stores is very sensitive to the geometric relationship between these channels. Under normal conditions, the gating behaviour of the surface membrane calcium channels may be near optimal (or well ?tuned') for activating calcium sparks which will minimise the requirement for calcium influx into the cell. In the spontaneous hypertensive rat (SHR) model of hypertension, the relationship between the calcium channel activity and calcium release from internal stores is altered in a way that results in a reduced contraction strength. The relationship between the calcium channel current and Ps is restored by beta-adrenergic stimulation in the hypertrophy model but not in hearts which are failing. These results suggest that a novel approach to treating certain types of heart failure could be to modify the gating behaviour of the sarcolemmal calcium channel to ?retune' ability of the sarcolemmal calcium channels to activate calcium release from internal stores, and thereby improve contractility without increasing calcium influx into the cell. PMID- 9364272 TI - Pulmonary hypertension, family and environment. AB - The focus of interest on pulmonary hypertension (PH) has come through recent therapeutic advances which prolong and improve quality of life. From this interest, recent observations form family studies indicate that a gene located on chromosome 2 is associated with PH. Environmental factors, the use of an anorectic agent, dexfenfluramine, has been associated with a risk of developing primary PH. A link with hypoxic induced PH has emerged in that a strain of rat, the fawn-hooded rat (FHR) which has a susceptibility to developing PH with mild hypoxia has an inherited storage defect to serotonin. Dexfenfluramine, by inhibiting the serotonin transporter, produces a similar pattern of disturbance of biogenic amine metabolism. This observation provides some insight into potential mechanisms for this complex disorder. PMID- 9364273 TI - Can hypertension be prevented? PMID- 9364274 TI - Ethnicity and cardiovascular risk: variations in people of African ancestry and South Asian origin. AB - Mortality from coronary heart disease (CHD), stroke and end-stage renal failure are high in South Asian migrants in the UK. This is associated with high prevalence of diabetes and hypertension. These seem to be manifestations of a metabolic syndrome with insulin resistance (hyperinsulinaemia) and central obesity (based on high waist-to-hip ratio rather than on conventional measures of body mass index). This is associated with sedentary lifestyle, high serum triglycerides and low HDL-cholesterol. Mortality from stroke and end-stage renal failure are high in black migrants to the UK (both Caribbeans and West Africans). However, CHD mortality is low in this group. This pattern of mortality is associated with high prevalence of hypertension and diabetes. This group tends to be obese (particularly women) according to conventional measures of body mass index and to have hyperinsulinaemia, low serum triglycerides and high HDL cholesterol. Conventional risk factors such as cigarette smoking and hypercholesterolaemia are less prevalent in ethnic minority populations in the United Kingdom and unlikely to explain the differences seen between groups, although each risk factor is likely to contribute to the variation in vascular disease within each group. There is difficulty in reconciling the results of migration studies (eg, from rural to urban environments) pointing to major environmental influences on the changes in cardiovascular risk factors with the consistent pattern of disease of ethnic groups across the world and in subsequent generations, suggesting a certain degree of genetic susceptibility. Important environment-gene interplays might be underlying some of these processes. The detection and management of hypertension and diabetes are still unsatisfactory in inner city areas and show variations by ethnic origin. Strategies for the control of CHD and stroke adopted in European countries directed mostly to white populations may be inappropriate for ethnic minority populations. PMID- 9364275 TI - Transgenic rats as models for hypertension. PMID- 9364276 TI - Incidence of diabetes and gout in hypertensive patients during 8 years of follow up. The General Practice Hypertension Study Group. AB - Hypertension has been shown to be closely associated with metabolic disorders such as diabetes mellitus and gout. The aim of this study was to establish the incidence of both these diseases in hypertensive patients and their age-matched controls and to assess the risk associated with diuretic treatment. The results refer to the data base of 2295 hypertensive and 2280 controls from the General Practice Hypertension Study Group who were screened for hypertension. The rescreened hypertensive subjects (n = 1190) and their controls (n = 938) were followed for an average of 8 years. The diagnosis of diabetes and gout was made by their general practitioners. After 8 years of follow-up, diabetes mellitus was diagnosed in 5.0% of hypertensive and 1.5% normotensive subjects. The diagnosis of gout was made in 3.1% and 0.9%, respectively. Moreover, diabetes mellitus occurred more frequently in both hypertensive men and women, with diuretic treatment and without (respectively, men given diuretic: relative risk (RR) = 2.74, 95% confidence interval (CI): 0.99, 7.5; and men not given diuretic: RR = 2.25, 95% CI: 1.0, 5.3: women RR = 4.03 95% CI: 1.5, 10.8, and RR = 3.47, 95% CI: 1.4, 8.9) in comparison with their age-matched controls. For gout the excess was confirmed in hypertensive men with and without diuretic treatment (RR = 6.25 (95% CI: 2.4, 16.7) vs 3.93 (95% CI: 1.6, 9.7)). PMID- 9364277 TI - Plasma and urinary nitrate in essential hypertension. PMID- 9364278 TI - Association between abdominal aortic diameter and peripheral vascular disease. AB - Fifty-four elderly people 81.2 years +/- 7.4 (mean age +/- s.d., range 66-98 years) were selected. These included 20 men (78.6 +/- 6.4 years, range 70-91 years) and 34 women (82.2 +/- 7.6 years, range 66-98 years). The relationship between the size of the abdominal aorta and various cardiovascular risk indicators such as calf:-brachial systolic pressure ratio, plasma cholesterol, triglycerides, and random blood glucose were examined. Abdominal aortic diameter correlated well with calf:-brachial systolic ratio measured by Doppler method over the posterior tibial artery and taking the lowest result of the right and left side (r = -0.28, P = 0.04). This correlation tended to be stronger in men (r = -0.55, P = 0.02) compared to women (r = -0.10, P = 0.57). However, the relationship tended to be confined to the systolic pressure in the left leg, raising the hypothesis that left-sided vascular disease is better related to aortic diameter, possibly due to a difference in the effects of reflected waves between the two sides. This needs further investigation. The contrast between the sexes was seen in the absence of any significant difference in resting blood pressure and calf:brachial systolic pressure ratio between the two. This finding suggests that the sex differences in the relationship between the size of the abdominal aorta and calf:brachial systolic pressure ratio are related to intrinsic properties of the arterial wall. PMID- 9364279 TI - Left ventricular geometry in presenting untreated hypertension. AB - In order to investigate the spectrum of geometry in our patient population, 63 untreated hypertensives underwent two-dimensional echocardiography. Left ventricular (LV) mass index and relative wall thickness, a measure of wall thickness in relation to cavity size, were calculated from the M-mode strip. In addition, to assess the sphericity of the left ventricle the ratio of LV minor to major hemiaxis was calculated. The subjects comprised 41 men (17 Caucasian, 22 Afro-Caribbean and two Oriental), and 21 women (five Caucasian, 12 Afro-Caribbean and two Oriental). Concentric hypertrophy was present in 46% of subjects, concentric remodelling in 32% of subjects, eccentric hypertrophy in only 6% of subjects and a normal left ventricular shape in 16% of subjects. The degree of sphericity of the left ventricle was similar among the four groups, suggesting that it does not change in uncomplicated hypertension. In contrast to the previously published combined series from Sassari and New York we had a low proportion of patients with either eccentric hypertrophy or normal left ventricular geometry. This is probably due to the high proportion of Afro Caribbean subjects in our clinic population who are more likely to have left ventricular hypertrophy. PMID- 9364281 TI - Slow vagal inhibition in neurones of the ventrolateral medulla oblongata of the rat: a possible mechanism for tonic, vagally evoked sympatho-inhibition. PMID- 9364280 TI - Left ventricular hypertrophy, blood pressure and ACE genotype in untreated hypertension. AB - It has been suggested that the deletion polymorphism of the angiotensin converting enzyme (ACE) genotype may be important in the development of left ventricular hypertrophy (LVH). In order to test this hypothesis we investigated the interaction between blood pressure (BP), LVH and ACE genotype in 86 previously untreated hypertensive patients. Each underwent two-dimensional and Doppler echocardiography and ACE genotyping. There were no significant differences in BP, the parameters of left ventricular structure (including left ventricular mass index) or diastolic function between the three genotype groups. Additionally, there were no significant differences in the relationship between systolic BP and left ventricular mass index among the three genotype groups (II genotype, r = 0.46, P = 0.02; ID genotype, r = 0.42, P = 0.01; DD genotype, r = 0.34, P = 0.10; F = 0.38). In contrast to some previous studies, we have found in this group of previously untreated hypertensive subjects no evidence to suggest that the deletion polymorphism of the ACE genotype is important in the development of LVH. PMID- 9364283 TI - Adrenomedullin acts as a local mediator of vascular homeostasis through interactions which lead to reduced endothelin-1 synthesis and secretion. PMID- 9364282 TI - Problems associated with using Fura-2 to measure free intracellular calcium concentrations in human red blood cells. PMID- 9364284 TI - Evidence of platelet activation in hypertension. AB - To test the hypothesis that platelet activation is present in hypertension, we measured plasma markers beta thromboglobulin and soluble P-selectin in hypertensive patients and normotensive controls. Both markers were raised in the patients (P < 0.05), and in a subgroup of patients, beta thromboglobulin was reduced with successful treatment of hypertension with the ACE inhibitor quinapril. We suggest that reversible platelet activation is present in hypertension. This may be a contributing factor to the link between this risk factor and the development of thrombotic disease such as stroke. PMID- 9364285 TI - Inhibition of proliferation by heparin and expression of p53 in cultured human vascular smooth muscle cells. AB - Human vascular smooth muscle cells (HVSMC) cultured from restenotic lesions are resistant to inhibition of proliferation by heparin. We examined if altered expression of p53 protein might be related to this phenomenon. HVSMC were cultured from saphenous vein and p53 protein levels examined using immunocytochemistry, and by immunoprecipitation with antibodies specific for wild type or mutant conformations followed by SDS PAGE and immunoblotting. Inhibition of proliferation by heparin was measured in 14-day growth assays. Elevated levels of p53 were found in five out of 41 HVSMC strains. The accumulated p53 protein was not precipitated by a mutant conformation-specific anti-p53 antibody in any of the five strains. In one of the five positive strains there was concomitant human cytomegaloviral infection. No significant difference was found between efficacy of heparin in the p53-positive and -negative strains. Furthermore heparin had no detectable effect on p53 protein levels. Although aberrant levels of p53 are detectable in a minority of HVSMC strains, these data do not support a role for altered p53 expression in resistance to the growth inhibitory effects of heparin in these cells. PMID- 9364286 TI - Trimebutine: mechanism of action, effects on gastrointestinal function and clinical results. AB - The actions of trimebutine [3,4,5-trimethoxybenzoic acid 2-(dimethylamino)-2 phenylbutylester] on the gastrointestinal tract are mediated via (i) an agonist effect on peripheral mu, kappa and delta opiate receptors and (ii) release of gastrointestinal peptides such as motilin and modulation of the release of other peptides, including vasoactive intestinal peptide, gastrin and glucagon. Trimebutine accelerates gastric emptying, induces premature phase III of the migrating motor complex in the intestine and modulates the contractile activity of the colon. Recently, trimebutine has also been shown to decrease reflexes induced by distension of the gut lumen in animals and it may therefore modulate visceral sensitivity. Clinically, trimebutine has proved to be effective in the treatment of both acute and chronic abdominal pain in patients with functional bowel disorders, especially irritable bowel syndrome, at doses ranging from 300 to 600 mg/day. It is also effective in children presenting with abdominal pain. PMID- 9364287 TI - Role of tenascin in human immunoglobulin A nephropathy. AB - Tenascin is a component of the extracellular matrix that responds rapidly to inflammation or injury. The activity index and chronicity index of immunoglobulin A nephropathy are mainly used to decide whether or not steroid therapy is indicated, but are sometimes difficult to evaluate histologically. We investigated whether tenascin staining of the glomeruli was an indicator of the activity or chronicity indices in patients with immunoglobulin A nephropathy. Tenascin staining was evaluated immunohistochemically in 38 renal specimens, including 32 from patients with immunoglobulin A nephropathy and six from control kidneys, and the extent of staining was scored. Tenascin staining was correlated with the chronicity index (r = 0.643, P < 0.0003) but not with the activity index. PMID- 9364288 TI - Effect of keigai-rengyo-to, a Japanese kampo medicine, on neutrophil functions: a possible mechanism of action of keigai-rengyo-to in acne. AB - On the basis of recent reports that keigai-rengyo-to (TJ-50), an oral Japanese Kampo (herb) medicine, is clinically effective in treating acne, and that tetracyclines are effective against acne by acting directly as an antioxidant on infiltrated neutrophils, we investigated the effect of TJ-50 on the generation of reactive oxygen species (ROS), using human neutrophils and a cell-free, xanthine xanthine oxidase system. The species investigated were superoxide radical anion (O2-), hydrogen peroxide (H2O2), and hydroxyl radical (OH.). In addition, neutrophil chemotaxis, phagocytosis and calcium concentration, [Ca2+]i in neutrophils were also assessed. TJ-50 significantly decreased neutrophil generated O2-, H2O2 and OH. in a dose-dependent manner. Three kinds of ROS generated in the cell-free system were also reduced in the presence of TJ-50. On the other hand, the medicine did not markedly affect neutrophil chemotaxis, phagocytosis or [Ca2+]i in neutrophils. Our results indicate that the clinical effectiveness of TJ-50 in the treatment of acne may be due partly to its antioxidant action on infiltrated neutrophils. PMID- 9364289 TI - Efficacy of gamma-linolenic acid in the treatment of patients with atopic dermatitis. AB - Of 60 patients with atopic dermatitis (30 males and 30 females, 15-30 years old) 30 were treated with gamma-linolenic acid of (C18:3 n-6) at a dosage of 274 mg twice a day; the other 30 patients were given placebo. The patients were treated for 12 weeks, during which their symptoms were assessed on a linear scale both by a dermatologist and by themselves every 4 weeks. The patients who received gamma linolenic acid, showed gradual improvements in pruritus, erythema, vesiculation and oozing, which were statistically significant compared with the control group (P < 0.001). Only one patient had presented with scaling at the beginning of the study and this symptom appeared to be less influenced by the effects of gamma linolenic acid. The assessments of symptoms made by the dermatologist were generally consistent with those made by the patients themselves. gamma-linolenic acid was found to be effective and without side-effects for the treatment of atopic dermatitis. PMID- 9364290 TI - Influence of a mineral water on the rheological characteristics of reconstituted infant formulas and diluted cows' milk. AB - A bottled spring water with a low mineral content was compared with tap water in the reconstitution and/or dilution of five different infant formulas and cows' milk. The osmolality, buffering power and renal solute load potential of the formulas reconstituted with the bottled water were all significantly lower than when tap water was used (P < 0.01). When the bottled water was used to dilute cows' milk, the morphology of milk casein precipitates (after addition of rennet) was finer and more dispersed than when tap water was used. For formula reconstitution and milk dilution, a benefit, in terms of solute/electrolyte balance, appears to be conferred on infants by the improved rheological characteristics of modified milks reconstituted or diluted with this bottled mineral water. PMID- 9364291 TI - An open, multicentre, comparative study of the efficacy and safety of azithromycin and co-amoxiclav in the treatment of upper and lower respiratory tract infections in children. The Paediatric Azithromycin Study Group. AB - An open prospective, multicentre, comparative, randomized (2:1) study was conducted in 481 children diagnosed as having mild-to-moderate lower respiratory tract infections. The efficacy and safety of azithromycin suspension (10 mg/kg), dosed orally once daily for 3 days, was compared with that of co-amoxiclav (10 mg/kg in a 4:1 ratio), dosed orally three times daily for 5-10 days. The proportion of evaluable patients (n = 472) showing a cure or improvement was significantly higher in the azithromycin group (96.8%) than in the co-amoxiclav group (91%, P = 0.0199). There were six relapses in both groups, giving an overall response rate of 95% for azithromycin versus 87.1% for co-amoxiclav (P = 0.0025). Adverse events were reported in 10% of the patients treated with azithromycin, and 11.3% of co-amoxiclav patients. Reported and counted compliance was significantly better in the azithromycin group. A 3-day regimen of azithromycin was as effective and as safe as a 5-10 day regimen of co-amoxiclav in the treatment of respiratory tract infections in children, and compliance was improved. PMID- 9364292 TI - Lack of association between vigabatrin and impaired cognition. AB - Of 14 patients with a history of partial epilepsy who received vigabatrin 2 g daily for 6 months, eight were newly diagnosed and received vigabatrin as monotherapy, while the remaining six received vigabatrin in addition to pre existing treatment with phenobarbitone. Neurophysiological and neuropsychological evaluations, done before and after the therapeutic period, included the Luria Nebraska neuropsychological battery (LNNB), electroencephalograms (EEGs) and evoked potentials. The results for each item of the test battery at baseline were compared with those after 6 months' treatment. There were no statistically significant differences on the functional scales of the LNNB, the EEG or the evoked potentials. There was a significant improvement (P = 0.01) in the LNNB topographic scales for the right frontal lobe and the motor-sensory area following treatment. These results indicate that vigabatrin has no detrimental effects on cognitive function and may improve function. PMID- 9364294 TI - Molecular genetics of gynecologic cancer. AB - During the past decades, the expansion of molecular biology has had a pivotal role in understanding the basis of cancer development and progression. In addition, real advances have been made in the application of DNA recombinant technology to cancer therapy and patient management. In gynecologic oncologic fields, there are also many investigations to explore the basic pathogenesis of gynecologic cancer, such as cervical cancer, ovarian cancer, and endometrial cancer. It is now known that specific types of human papilloma virus (HPV) are the principal etiologic agents for both cervical cancer and its precursors. However, the various kinds of alterations in oncogenes and tumor suppressor genes may play additional roles in carcinogenesis of cervical cancer. Although ovarian carcinoma is the most frequent cause of death from gynecologic malignancies, the histogenesis and biological characteristics of these tumors are not well understood. During the last several years, many key observations have been made concerning the genetic alterations associated with ovarian cancer. Recent researches including some dominant oncogenes and tumor suppressor gene mutations common to these malignancies are providing bases to elucidate the mechanisms underlying this cancer. The most important basis of endometrial cancer is that K ras and p53 mutations are also frequently observed. PMID- 9364293 TI - The effects of a fluoroquinolone on the growth and development of infants. AB - Growth and development were monitored for up to 42 months in nine neonates to whom ciprofloxacin, a fluoroquinolone, was given in the neonatal period at a dosage of 20 mg/kg/day. Ciprofloxacin was used only as a ?life-saving' therapy in cases of sepsis produced by bacterial agents resistant to other antibiotics. Two other groups of nine neonates, matched by birth weight and gestational age, were studied as controls: one group with sepsis, which was effectively treated with cefotaxime and a group of healthy neonates. No statistically significant differences in growth and development between the groups were found during follow up for 42 months. No osteoarticular problems or joint deformities were observed in the ciprofloxacin group. Ciprofloxacin appears to provide a therapeutic option as a ?life-saving' therapy for newborns with sepsis produced by multiply resistant organisms. PMID- 9364295 TI - The angiotensin converting enzyme genetic polymorphism in acute coronary syndrome -ACE polymorphism as a risk factor of acute coronary syndrome. AB - The deletion polymorphism of angiotensin converting enzyme (ACE) genotype has been reported as an independent risk factor for the development of myocardial infarction (MI). However there are conflicting data showing no relationship between the ACE genotype and coronary artery disease. The present study was performed to investigate the correlation between ACE genetic polymorphism and acute coronary syndrome by comparing the distribution of ACE genotypes and ACE activities in patients with acute MI and unstable angina with those in control group. The frequency of genotype DD was significantly higher in patients with acute coronary syndrome than in controls. Logistic regression analysis showed that ACE polymorphism affected the development of acute coronary syndrome in recessive pattern of D allele. When we divided the patients into MI and unstable angina groups, the frequencies of genotype DD and D allele were significantly higher in unstable angina group than in MI or control groups. In the patients with MI, the frequency of D allele was significantly higher in patients without previous angina than in those with previous angina. There was no significant difference in ACE genotype or allelic frequency according to the severity of coronary lesions. The ACE genotype was associated with marked differences of ACE activity, but there was no difference between the patient and control groups for each genotype. In conclusion, the genotype DD of ACE gene associated with acute coronary syndrome, but not with the severity of coronary artery lesion. These results showed that the genotype DD of ACE gene might be associated with acute coronary syndrome by another mechanism rather than the coronary atherosclerosis. PMID- 9364296 TI - Proteoglycan in porcine aortic tissue after cryopreservation. AB - This study was to investigate the effects of cryopreservation on proteoglycans of arterial conduit tissue. Proteoglycans from fresh and cryopreserved porcine aorta tissues were extracted with 4 M guanidine hydrochloride (Gdn-HCl) at 4 degrees C in the presence of protease inhibitors. From the tissue extracts, proteoglycans were isolated by cesium chloride (CsCl) isopycnic centrifugation and fractionated by gel filtration. Quantitative analysis of extracted proteoglycans revealed that the content of proteoglycans from cryopreserved tissue, measured as the amount of uronate and protein per unit weight of wet tissue, was similar to that from fresh tissue (0.44 +/- 0.300 versus 0.43 +/- 0.007 mg uronate/g wet tissue and 3.14 +/- 0.039 versus 2.64 +/- 0.015 mg protein/g wet tissue). Gel permeation column chromatography studies suggested that proteoglycans present in three CsCl fractions (I, II, and III) from cryopreserved tissue have approximately the same molecular weights as those from fresh tissue; Kav = 0.13 and 0.47 (I), 0.20 (II), and 0.43 (III) from cryopreserved tissue versus Kav = 0.13 and 0.50 (I), 0.23 (II), and 0.40 (III) from fresh tissue. These studies indicate that there is no significant alteration in the content and molecular size of proteoglycans in properly cryopreserved aortic tissue. PMID- 9364297 TI - Do hematocrit and serum fibrinogen influence transcranial Doppler measurements? AB - To investigate the effect of hematocrit and serum fibrinogen on transcranial Doppler ultrasound (TCD) measurements, we performed, TCD tests and measured hematocrit and serum fibrinogen concentrations in 112 healthy adult volunteers. The mean velocities of the middle cerebral (r = -.37, p < .0001), internal carotid at siphon (r = -.14, p < .05) and cervical level (r = -.14, p < .05), vertebral (r = -.21, p < .005) and the basilar artery (r = -.33, p < .001) were significantly and inversely correlated with hematocrit, while serum fibrinogen weakly affected the mean velocities of the internal carotid artery. The subjects with low hematocrit (< or = 40%) showed significantly higher mean velocities of the middle cerebral, vertebral and basilar arteries than those with high hematocrit (> 40%). Considering the influence of the subject's age and gender, hematocrit is the strongest factor influencing the velocities of the middle cerebral and the basilar artery. These results suggest that hematocrit is an important variable for TCD measurements of the cerebral blood velocities and should be taken into account in TCD application. PMID- 9364298 TI - Doppler flow velocity waveforms of human fetal ductus arteriosus and branch pulmonary artery. AB - Doppler waveforms of the human fetal ductus arteriosus and the branch pulmonary artery are distinct in their shape and might reflect fetal cardiovascular hemodynamics and vessel wall characteristics. The waveform of ductus arteriosus had two peaks, a higher one in systole and a lower one in diastole. Both peaks had slow acceleration and deceleration and looked like two narrow base isosceles triangles. This unique waveform might be due to vessel wall characteristics and an instantaneous pressure gradient between the main pulmonary artery and descending aorta. The waveform of the branch pulmonary artery showed very steep acceleration with the onset of ejection followed by steep decline, then low velocity flow during diastole. The characteristic shape of the branch pulmonary artery might be related to high vascular resistance, decreased capacitance and the earlier reflection wave of pulmonary vessels. PMID- 9364299 TI - Squamous cell carcinoma of the tonsil--clinical features and treatment results. AB - Squamous cell carcinoma of the tonsil has a relatively poor prognosis. Aggressive surgery, radiation therapy and combinations of irradiation and surgery have been employed but there exists some controversy about the efficacy of these treatment modalities. The purpose of this paper is to compare the efficacy of treatment between the surgery followed by radiation therapy and the preoperative radiation therapy followed by surgical resection. The medical records of 33 patients treated for squamous cell carcinoma of the tonsil at the Department of Otolaryngology-Head and Neck Surgery, Korea University Hospital between 1989-1993 were reviewed retrospectively. None of the patients were stage I, but stage II, III, and IV were four, five, and 24 patients, respectively. There were 30 males and three females. The most common histopathology was moderately differentiated squamous cell carcinoma (20/33). The 13 patients treated initially with surgery had an overall three-year survival rate of 38.5%, and the rate for the 20 patients treated initially with radiation was 40%. The main pattern of treatment failure was a local recurrence and neck metastases, and pathologic differentiation thought to be an important prognostic factor. Complications are fewer in patients treated initially with surgery (23.1%) than patients initially treated with radiation (50.0%). There is no difference in the efficacy between the two therapeutic groups. PMID- 9364300 TI - Decreased gastric proliferation of foveolar epithelial cells after the eradication of Helicobacter pylori. AB - Increased epithelial cell proliferation is associated with an increased risk of gastric carcinoma. Helicobacter pylori infection is an established risk factor for gastric cancer and the organism has recently been classified as a group I carcinogen by an IARC working group. In this study, we describe differences in gastric epithelial cell proliferation between a H. pylori eradicated group (n = 21) and a not eradicated group (n = 8) after anti-H. pylori eradication therapy to show that increased cell proliferation is associated with H. pylori infection. H. pylori infection was determined by rapid urease test and immunohistochemical method with anti-H. pylori polyclonal antibody. Gastric epithelial cell proliferation was assessed using immunohistochemical method using Ki-67 monoclonal antibody. Ki-67 positive cells in H. pylori associated chronic active gastritis were observed in the glandular neck and the upper portion of foveolar epithelium. Patients who cleared their H. pylori infections showed a significant decrease of Ki-67 labeling index after therapy (0.73 +/- 0.10 vs. 0.48 +/- 0.08, p < 0.01). By contrast, Ki-67 labeling index before and after treatment in patients who remained positive for H. pylori showed no significant difference (0.78 +/- 0.08 vs 0.74 +/- 0.10, p > 0.05). These results indicate that H. pylori infection increases the proliferation of gastric foveolar epithelium, which is reduced by the eradication therapy. We suggest that anti-H. pylori eradication therapy can prevent mucosal cell proliferation to be closely associated with gastric carcinogenesis. PMID- 9364301 TI - Relationship of transforming growth factor beta 1 to angiogenesis in gastric carcinoma. AB - Transforming growth factor-beta (TGF-beta) comprises a group of multifunctional regulatory proteins, whose effects include angiogenesis. The expression of TGF beta 1 in gastric carcinomas (70 cases) has been determined and related to pathological features and microvessel count by immunohistochemical staining for TGF-beta 1 and Factor VIII related antigen. Prominent reactivity for TGF-beta 1 was associated with the depth of invasion (r = 0.2; p < 0.05) and increased microvessel count (r = 0.5; p < 0.05). Also, the microvessel count had a significant correlation with invasiveness (r = 0.34; p < 0.05) and lymph node metastasis (r = 0.28; p < 0.05). These findings indicate that TGF-beta 1 may have a role in tumor invasion and angiogenesis. PMID- 9364302 TI - Effect of suramin on differentiation of human stomach cancer cell lines. AB - This study was designed to demonstrate that differentiation of stomach cancer cells can be modified by microenvironmental change and to look for a method inducing or promoting tumor cell differentiation. To evaluate the biomorphological characterization of tumor cell differentiation in suramin containing in vitro culture of human stomach cancer cell lines, inverted phase contrast microscopic examination, analysis of growth curves and BrdU-positive S phase fraction, immunocytochemical study, radioimmunoassay for CEA, transmission electron microscopic examination, DNA flow cytometry, and heterotransplantation in SCID mice were performed. Suramin inhibited tumor cell growth. Development of intracytoplasmic lumina and intercellular lumina was noted in suramin-containing culture with formation of numerous microvilli and frequent desmosomes. The amount of CEA released by a cell was increased in suramin-containing culture. Suramin inhibited heterotransplantation, and a transplant from suramin-containing culture revealed a much higher degree of differentiation than that from suramin-absent culture. Suramin induced no change in DNA ploidy pattern. Elimination of suramin from the culture medium did not reverse the tumor cell differentiation. Each stomach cancer cell line showed a different degree of responsiveness to suramin. In conclusion, this study shows that suramin inhibits growth of SNU-5 and SNU-16 cells and that suramin induces differentiation of SNU-16 cells. PMID- 9364303 TI - Cleaved variant of plasmacytoma with myelomonocytic differentiation- immunohistochemical and ultrastructural studies. AB - Although plasma cells are terminally differentiated B cells, neoplastic plasma cells frequently express not only pre-B cell antigen, but also megakaryocytic, myelomonocytic, or erythroid markers. Since morphologic diagnosis of plasmacytoma is based on the recognition of neoplastic cells closely resembling normal plasma cells, unusual morphologic variants of neoplastic cells associated with these aberrant immunohistochemical features frequently cause diagnostic difficulty. The authors report a case of plasmacytoma with cleaved nuclei and myelomonocytic features occurring in the clavicle. The tumor was composed of immature plasma cells showing irregular, cleaved, and multilobated nuclei and abundant cytoplasm with prominent eosinophilic granules. A few tumor cells showing recognizable plasmacytic differentiation were admixed within the tumor. Immunohistochemically, the tumor cells expressed CD45RB, CD68, lysozyme, myeloperoxidase and kappa light chain with focal positivity for lambda chain. Ultrastructurally, the tumor cells contained numerous membrane bound electron dense lysosomal granules, some of them resembling Auer rods, as well as rough endoplasmic reticula arranged in lamellated stacks. Small biopsied nasal mucosal tissue in same patient revealed well differentiated plasmacytoma composed of tumor cells showing round, eccentric nuclei devoid of marked nuclear cleavage and cytoplasmic granularity. Immunohistochemically, these cells were kappa(+), lambda(-), myeloperoxidase(-), lysozyme(-) and CD68(-). PMID- 9364304 TI - Epstein Barr virus associated hemophagocytic syndrome--a case report. AB - Virus associated hemophagocytic syndrome (VAHS) are a heterogeneous group of disorders in which viral infection is associated with a proliferation of hemophagocytic histiocytes through the reticuloendothelial system. We report the case of a 21-year-old Korean man who presented to us with high fever, marked hepatosplenomegaly, severe hepatic dysfunction, coagulopathy, pancytopenia and marked panhypogammaglobulinemia. Bone marrow aspiration and biopsy showed histiocytes proliferation with active phagocytosis of red cells and neutrophils. Primary Epstein-Barr (EB) viral infection at presentation was confirmed by the presence of IgM antibody to viral capsid antigen (VCA) with absence of antibody to EB viral nuclear antigen (EBNA). A liver biopsy performed one month after the presentation showed erythrophagocytic histiocytes within the sinusoids. EB virus was demonstrated in the liver biopsy tissue by DNA PCR method, and EBER mRNA in situ hybridization. PMID- 9364305 TI - Microvillus inclusion disease in two Korean infants. AB - We report two cases of microvillus inclusion disease and these are the first cases in Korea. The two babies (one baby had a sibling who died of diarrhea in the neonatal period) had excreted their stools up to 200 ml/kg per day since several days after birth. Workup's included extensive infectious, immunologic, hormonal and rheumatologic studies, all of which were negative or normal. Diagnosis rested on the ultrastructural finding of intracytoplasmic inclusions that contained intact microvilli on electron microscopy. We tried somatostatin analogue (octreotide, 4 micrograms/kg/day), cholestyramine (up to 4g t.i.d.), steroid (prednisone, 2 mg/kg/day) and intravenous epidermal growth factor (100 ng/kg/hr for 2 weeks), but there was mild improvement with cholestyramine (decrease stool volume) and epidermal growth factor (increase the number of microvilli per cell) but no improvement was noted with the other treatments. Although it is a rare disorder and the prognosis of microvillus inclusion disease is poor, it must be considered if an infant has chronic secretory diarrhea. PMID- 9364306 TI - Intravascular lymphomatosis of the T cell type presenting as interstitial lung disease--a case report. AB - Intravascular lymphomatosis (IL) is a rare and generally fatal disease characterized by proliferation of large lymphoma cells almost exclusively within the lumen of small blood vessels. The skin and central nervous systems are typically affected, but involvement of other organs, such as lung, has been described. Predominant lung involvement without cutaneous and neurologic manifestation is very rare and difficult to diagnose. Originally considered as an endothelial disorder, IL has recently been reclassified as lymphoma. Most of the cases reported are of B cell lineage with a few cases of T cell type. We describe a case of the T-cell type IL manifested clinically as an interstitial lung disease without involvement of skin and central nervous systems. Immunohistochemical studies showed the T-cell nature of the neoplastic cells in open lung biopsy sample. PMID- 9364307 TI - Basal cell adenocarcinoma of the salivary gland--a case report. AB - Basal cell adenocarcinoma of the salivary gland is a very rare disease entity as the malignant counterpart of basal cell adenoma. On the basis of morphologic pattern, basal cell adenoma can be divided into four subtypes; trabecular, solid, tubular, and dermal analogue (membranous). We report a case of basal cell adenocarcinoma in the left parotid gland of a 33-year-old woman. Light microscopically, the tumor cells were composed of relatively uniform, monotonous basaloid cells. The tumor cell nests commonly had peripheral palisadings. The main growth pattern of the tumor cells was tubulotrabecular. However, other portions were similar to dermal analogue monomorphic adenoma and showed cribriform patterns reminiscent of adenoid cystic carcinoma. The tumor had frequent perineural invasions and an infiltrative margin. On immunohistochemistry, only scattered numbers of tumor cells showed irregular positive reaction for S-100 protein, suggesting a few myoepithelial cell components of the tumor compared with most tumor cells derived from epithelial cells. PMID- 9364308 TI - Flat depressed early colon cancer--a case report. AB - A flat depressed early colon cancer (FDEC) is characterized by non-polypoid growth pattern, no association of adenomatous tissues and a tendency of even small lesions toward submucosal invasion and lymph node metastasis. It supports de novo carcinogenesis of colorectal cancer, although most colorectal cancers arise in pre-existing adenoma (adenoma-carcinoma sequence). There have been few reports of small depressed cancers because of the difficulty in colonoscopic detection and the rapid development to ulcerating advanced cancers. We report a case of flat depressed early colon cancer confined to mucosa detected by indigo carmine contrast colonoscopy. PMID- 9364309 TI - Pancreatic endocrine tumor admixed with a diffuse microcystic adenoma--a case report. AB - We report a case of pancreatic endocrine tumor admixed with a diffuse microcystic adenoma in a 67-year-old woman with a six months history of melena. Whipple's operation and near-total pancreatectomy were performed under the impression of a pancreatic cancer with duodenal invasion. The pancreas was enlarged and was entirely replaced by sponge-like tiny cysts, which were lined by a single layer of periodic acid Schiff positive cuboidal cells. Also encountered was a gray white solid area at the head portion which extended to the duodenum with an intraluminal polyp formation. The compact area was composed of solid and acinar structures of tumor cells, which showed a positive reaction for chromogranin A and neuron specific enolase, separated by delicate highly vascularized stroma. To the best of our knowledge, this is the first case report published with immunohistochemical studies to deal with a pancreatic endocrine tumor admixed with a diffuse microcystic adenoma. PMID- 9364310 TI - Intracranial metastasis from clear cell sarcoma of the kidney--a case report. AB - Childhood kidney tumors seldom metastasize into the cranial cavity unless it is a special histological variant. We report a 4-year-old boy with multiple intracranial metastases in the left parietotemporal and right cerebellar area from primary clear cell sarcoma of the kidney without evidence of bony metastases. Metastatic tumor revealed nests of uniformly polygonal cells with clear cytoplasm demarcated by delicate fibrovascular arcades. Tumor cells were positive for vimentin and negative for cytokeratin, S-100 protein, desmin, and myoglobin. Cellular proliferation rate measured by PCNA, and Ki-67 was not significantly different between primary tumor mass and metastatic brain lesion. Expression of p53 oncoprotein was not evident in both lesions. These findings suggested that the relapse and metastasis of clear cell sarcoma of the kidney was probably due to regrowth of micro-metastases which were present at an early stage of disease. PMID- 9364311 TI - Ureteral fibroepithelial polyp associated with ureteropelvic junction obstruction in a child. AB - Ureteral fibroepithelial polyp is an unusual benign tumor of a mesodermal origin. It is very rare in infants and children, and the majority of them, excluding ones secondary to chronic irritation, were presented as a single disease without associated lesion. We report a case of multiple ureteral fibroepithelial polyps associated with ureteropelvic junction obstruction in a 5 year-old boy. PMID- 9364312 TI - Current and future immunosuppressive therapies: impact on chronic allograft dysfunction. PMID- 9364313 TI - Mechanisms of defective hydroosmotic response in chronic renal failure. AB - The kidney's concentrating capacity is impaired in chronic renal failure (CRF) resulting in a relatively large rate of urine formation and nocturia. Normal renal concentrating ability depends on the maintenance of a hypertonic medullary interstitium, a structurally intact countercurrent multiplier system, and normal water permeability of the collecting tubules in response to arginine vasopressin (AVP). Each of these three components may be compromised in the setting of CRF. This review presents current knowledge regarding mechanisms of impaired renal concentrating ability in CRF, from the whole kidney level to the cellular and molecular level. PMID- 9364314 TI - Evaluation of peritoneal membrane integrity. AB - Peritoneal transport studies provide information on the vascular site the peritoneal membrane. The mass transfer area coefficient of creatinine mainly reflects the vascular peritoneal surface area, while the restriction coefficient to macromolecules reveals the intrinsic permeability of the peritoneal membrane. The Na+ dialysate/plasma ratio after a one hour 3.86% glucose dwell can be used as a rough indication of aquaporin-mediated water transport. Dialysate concentrations of cancer antigen 125 reflect the mesothelial cell mass. Ultrafiltration failure is the most frequent transport abnormality in long-term peritoneal dialysis and peritoneal sclerosis. Its association with high mass transfer area coefficients of creatinine suggests an increase in the vascular surface area due to neoangiogenesis, but the aquaporin-mediated water transport may also be disturbed. The decrease in dialysate CA 125 is compatible with a loss of mesothelial cell mass in long-term peritoneal dialysis. A proposal for a peritoneal membrane test is put forward. The main differences with the peritoneal equilibration test are: the use of 3.86% glucose, the determination of the Na+ dialysate/plasma ratio after one hour and of the dialysate CA 125 concentration after four hours. PMID- 9364315 TI - Current indications and limits of pancreatic islet transplantation in diabetic nephropathy. AB - Insulin-dependent diabetes mellitus (IDDM) is a disease caused by a progressive autoimmune destruction of the insulin-producing beta-cells within the pancreas. A major task of diabetes research consists in developing new forms of treatment to delay or prevent the development of the chronic complications associated with the disease. Islet transplantation could become an attractive alternative to whole organ transplantation, since it is a simpler and safer procedure. However, the requirement for long-term immunosuppression has limited the indication of islet transplantation to patients receiving a simultaneous kidney transplant or already bearing one. While the majority of recipients of islet allografts did not become insulin independent, the field has witnessed significant progress and the long term results in patients with even partial graft function are comparable or better than those achievable with intensive insulin therapy. Recent trials of donor bone marrow infusions combined with solid organ transplants are in progress to determine whether donor-specific tolerance can be achieved with the potential to expand the future indications of islet transplantation in diabetes. PMID- 9364316 TI - Hemolytic uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP) complicating adult Still's disease: remission induced with intravenous immunoglobulin G. AB - Coexistence of hemolytic uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP) and adult Still's disease is extremely rare. We describe the case history of a 22-year-old young man who presented with evidence of a thrombotic microangiopathy complicated by dialysis-dependent renal failure, encephalopathy, and an ischemic retinopathy. The most important and novel feature of this case was the dramatic and sustained clinical remission of the TMA induced by intravenous immunoglobulin (IVIg) after failure of plasmapheresis and glucocorticoids to do so. PMID- 9364317 TI - Pseudotumor cerebri in renal transplant recipients: a diagnostic challenge. AB - We describe two patients with renal transplants who developed pseudotumor cerebri (PTC) in the course of their follow-up. They illustrate the diagnostic challenge in such situations. Patients with renal transplants usually have many other associated conditions which may lead to headache, visual disturbances or papilledema. A high index of suspicion is necessary for prompt diagnosis and management of this rare and serious but treatable combination. PMID- 9364318 TI - Effect of exogenous reduced glutathione on the survival of red blood cells in hemodialyzed patients. AB - Reduced glutathione (GSH) is an important scavenger of free radicals in the red blood cell (RBC) membrane, and its deficiency may be a partial cause of increased hemolysis and shortened RBC survival in uremics. In this study we employed exogenous GSH (1200 mg i.v. at the end of each dialysis session for at least nine months) to treat anemia in a group of 28 hemodialyzed patients, 14 of whom were also receiving erythropoietin. RBC survival (51Cr T/2) was calculated before (26 patients) and at the end (15 pts) of GSH therapy. After the first three months anemia (RBC, hemoglobin, hematocrit, reticulocytes) improved significantly in 17 patients (60%), for as long as they were under therapy, but rapidly dropped to pre-treatment values when GSH was discontinued. The 51Cr T/2 increased significantly in responders, but not in those who did not respond. No significant differences were found between responders and non-responders as regards urea KT/V, PTH, serum iron, ferritin, dialysis membrane, dose of erythropoietin and basal 51Cr T/2. These results suggest that exogenous GSH may be a promising drug for the treatment of anemia in most hemodialyzed patients, particularly considering its low cost. PMID- 9364319 TI - Treatment of idiopathic nephrotic syndrome with cyclosporin A in children. AB - Twenty-two children (15 boys, 7 girls), aged from 1 to 9 years (mean 4.6 years) at the onset of idiopathic nephrotic syndrome (INS) received cyclosporin A (CsA) because of steroid toxicity or failure to respond to steroids. CsA was given at an initial dose of 5 mg/kg body weight per day, and adjusted to maintain whole blood trough levels at 60 to 180 ng/ml (HPLC). The duration of treatment ranged between 4 and 33 months. In patients who responded to CsA, treatment was continued for 6-33 months (average 12 months). Treatment was stopped it found to be ineffective after four months. All patients had normal kidney function at the onset of CsA therapy. Of the 22 cases 10 were frequent-relapsing, steroid responsive patients who suffered serious side effects of steroid therapy. Six steroid-responsive patients were dependent on high-dose prednisolone for maintenance of remission. Twelve patients were steroid-resistant (SRT), eight of them with mesangial hypercellularity (MES), three focal segmental glomerulosclerosis (FS-GS), and one minimal change disease (MCD). Seventeen patients (77%) responded favorably to CsA, 13 of them with complete remission, three with partial response (two of whom had MES, and one steroid-resistant FSGS), and one relapsed while on CsA. Only five patients in the whole study group showed no response to CsA, two of them had steroid-resistant FS-GS, both of whom developed renal failure in follow-up, and the other three had MES. In conclusion, therapy with CsA may be helpful in resolving nephrotic syndrome in SRT patients. CsA can be used to maintain remission in frequently relapsing nephrotic children. Patients who respond to CsA may have a lasting remission after the cessation of therapy. PMID- 9364320 TI - Actions of the neurotrophins on calcium uptake. AB - The neurotrophins are important for their long-term effects on the survival and differentiation of many types of neurons during development. They also appear to protect mature neurons from injury caused by nutrient or oxygen deprivation. More recently, the neurotrophins have been implicated in such short-term processes as synaptic plasticity. A great deal of evidence suggests that intracellular calcium levels play a key role in neuronal survival during normal development, in neuronal injury following nutrient or oxygen deprivation, and in synaptic plasticity as well. Maintaining appropriate intracellular levels of calcium is important for proper biological function and it has been shown that one of the actions of the neurotrophins is to modulate intracellular calcium levels in a number of in vivo and in vitro systems. Some information about the mechanism(s) by which this is accomplished is now available. Understanding the mechanisms of neurotrophin action should provide insights into the processes by which the brain functions and, further, provide therapeutic tools for the treatment of neuronal injury and neurodegenerative diseases. PMID- 9364321 TI - GDNF induces the calretinin phenotype in cultures of embryonic striatal neurons. AB - Glial cell line-derived neurotrophic factor (GDNF), a member of the transforming growth factor-beta (TGF-beta) superfamily, is a potent neurotrophic factor for several neuron populations in the central and peripheral nervous system. Members of the neurotrophin, neurokine, and TGF-beta families of growth factors can affect neurons beyond their capacity to promote survival. They can play instructive roles including the determination of a particular transmitter phenotype. Here, we show that GDNF enhances the number of calretinin (CaR) positive neurons in serum-free cultures of striatal cells isolated from embryonic rats. The effect is dose-dependent, can be elicited with concentrations as low as 0.1 ng/ml, and is not accompanied by increased incorporation of 5-bromo-2' desoxyuridine and appearance of glial fibrillary acidic protein-positive cells. Similar, but weaker effects can be elicited by brain-derived neurotrophic factor, neurotrophin-3 and -4, fibroblast growth factor-2. Ciliary neurotrophic factor, nerve growth factor, and TGF-beta 1 do not affect striatal CaR expression. GDNF can augment CaR-positive cells at any time point and with a minimal exposure of 18 hr, suggesting induction of the phenotype rather than increased survival. By reverse transcription polymerase chain reaction (RT-PCR), we show that GDNF is expressed in the E16 striatum and in cultures derived from this tissue. GDNF also protected striatal CaR-positive neurons against glutamate toxicity. We conclude that striatal GDNF, in addition to its retrograde trophic role for nigrostriatal dopaminergic neurons, may also act locally within the striatum (e.g., by inducing the CaR phenotype and protecting these cells against toxic insult). PMID- 9364322 TI - Cyclin-dependent kinase inhibitor p27kip1 is expressed at high levels in cells that express a myelinating phenotype. AB - Terminal cellular differentiation is generally accompanied by exit from the cell cycle but the molecular basis of how the two events are coupled is poorly understood. In the central nervous system (CNS) the terminally differentiated, non-proliferating myelin-synthesizing cells, oligodendrocytes, arise from stem cells that are proliferation competent. To study the molecular mechanisms that link oligodendrocyte differentiation and cell cycle control, the D6P2T cell line has been used. This cell line responds similarly to oligodendrocytes in culture in response to increased cyclic AMP (cAMP). Upon increasing cAMP levels, D6P2T cells increase transcription of the endogenous myelin basic protein (MBP) gene. The increase in MBP gene transcription is accompanied by withdrawal of the cells from the cell cycle. The mechanism of cell cycle withdrawal in response to cAMP was found to involve a dramatic increase in the level of the cyclin-dependent kinase (cdk) inhibitor p27kip1 with little or no change in the levels of the cyclins D1 and E. The increase in p27kip1 is at least partially attributable to an increase in the mRNA levels for p27kip1. A striking increase in the cdk inhibitor p27kip1 was also shown to occur in vivo in oligodendrocytes, the cells responsible for myelination in the CNS. In contrast to D6P2T cells, however, this increase in p27kip1 was accompanied by a decrease in the levels of cyclin E. PMID- 9364323 TI - Expression of CD40 induces neural apoptosis. AB - The tumor necrosis factor receptor superfamily includes 12 members, some of which (e.g., tumor necrosis factor receptor I and FAS) induce cell death triggered by ligand binding. Another member of the superfamily, the neurotrophin receptor p75NTR, induces neural apoptosis, with apoptosis being inhibited by binding of ligand to the receptor. As such, it is a candidate for the mediation of neurotrophin dependence. Here, we show that CD40, a superfamily member that is closely related to p75NTR, also induces neural apoptosis, but apoptosis is inhibited by binding of the G28-5 monoclonal antibody to CD40. These results provide further support for a model in which some members of the tumor necrosis factor receptor superfamily induce apoptosis triggered by ligand binding, whereas other members may, at least under certain conditions, induce apoptosis in the absence of ligand binding, with apoptosis being inhibited by binding of ligand or monoclonal antibody. PMID- 9364324 TI - mu-Opioids activate tyrosine kinase focal adhesion kinase and regulate cortical cytoskeleton proteins cortactin and vinculin in chick embryonic neurons. AB - We have investigated the signal transduction pathway of the G-protein mu-opioid receptor upstream of phospholipase D (PLD) and protein kinase C-epsilon (PKC epsilon) activation in postmitotic E6CH chick embryo cortical neurons. The mu opioid receptor and PLD-PKC-epsilon functional coupling depends on upstream tyrosine kinase activation. We now report that the mu-opioid agonists specifically stimulated tyrosine phosphorylation and activation of the focal adhesion kinase (FAK) in a time-dependent manner. We also demonstrate that met enkephalin, a mu-opioid agonist in E6CH cultures, significantly increases tyrosine phosphorylation of another Src kinase substrate, the cytoskeletal protein cortactin. Tyrosine phosphorylation of cortactin led to drastic changes in subcellular localization, an estimated 2-fold enrichment in the cytosol. Similarly, opioids stimulated a sustained tyrosine phosphorylation of vinculin, a protein enriched in focal adhesion sites. These data provide novel evidence that opioid receptor intracellular signaling engages the specific activation of tyrosine kinase FAK and regulates the neuronal cytoskeleton during central nervous system morphogenesis. PMID- 9364325 TI - Cell death of adult pyramidal CA1 neurons after intraventricular injection of a novel peptide derived from trkA. AB - Members of the nerve growth factor (NGF) family of neurotrophins bind to the second leucine-rich motif (LRM2) within the extracellular domains of their respective receptors (trkA, trkB, trkC). Small LRM2 peptides have been recently demonstrated to selectively bind the neurotrophins revealing similar complex binding characteristics as full-length receptors. We extend our recent findings, showing that the peptides (A and C) do not block nerve fiber outgrowth through high affinity trk receptors in a ganglia bioassay. Since the highest concentration of neurotrophins [NGF, brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3)] is found in the hippocampus, the peptides were injected into the 3rd ventricle of anesthetized adult rats. The (NGF binding) LRM2-A peptide, but not the (BDNF binding) LRM2-B or the (NT-3 binding) LRM2-C peptides, caused severe apoptotic neurodegeneration of hippocampal pyramidal CA1 neurons as revealed by cresyl violet staining and the TUNEL reaction. The degeneration was protected by intrahippocampal injection of NGF-beta and by the non-N-methyl-D aspartate (NMDA) antagonist CNQX (6-cyano-7-nitroquinoxaline-2,3-dione), indicating a glutamatergic mechanism. In situ hybridization revealed that pyramidal CA1 neurons did not express trkA and p75 receptor mRNA in sham and LRM2 A-lesioned animals. It is concluded that the LRM2-A peptide represents a novel peptide with properties to induce apoptotic cell death of pyramidal CA1 neurons and may be useful as an experimental agent. PMID- 9364326 TI - Changes in mitochondrial membrane potential during oxidative stress-induced apoptosis in PC12 cells. AB - We examined the effects of various types of oxidative stress on cell survival and on mitochondrial membrane potential (delta psi m) in PC12 cells transfected with BCL-2. Several types of oxidative stress such as exposure to hydrogen peroxide, 13-L-hydroperoxylinoleic acid, and xanthine + xanthine oxidase triggered apoptotic nuclear condensation and DNA fragmentation in normal PC12 cells. These types of oxidative stress induced significant increases in level of reactive oxygen species (ROS) before cell death. By contrast, BCL-2 prevented the apoptosis induced by these oxidative stresses. However, BCL-2 did not reduce ROS levels, indicating that it functions downstream of ROS generation. We measured delta psi m as a potential target of ROS during oxidative stress-induced cell death. Hydrogen peroxide, 13-L-hydroperoxylinoleic acid, and xanthine + xanthine oxidase induced a significant loss of delta psi m simultaneously with cell death. BCL-2 prevented the decrease in delta psi m as well as apoptosis induced by oxidative stress. These observations suggest that the oxidative stress triggers apoptosis associated with both increased generation of ROS and decreases in level of delta psi m and that BCL-2 prevents cell death as well as delta psi m but not ROS production. PMID- 9364327 TI - Transferrin is an early marker of hepatic differentiation, and its expression correlates with the postnatal development of oligodendrocytes in mice. AB - Transferrin (Tf), the iron transport protein, is essential for the growth and differentiation of cells. Therefore, it provides an excellent model to analyze the regulatory mechanisms controlling the expression of a eukaryotic gene in different cell types and during fetal and adult life. In this study, the tissue specific and developmental regulation of the Tf gene in vivo were analyzed. Human Tf mRNA was detected mainly in fetal and adult liver. A weaker expression was observed in adult and fetal brain and in fetal spleen. By in situ hybridization the presence of mouse Tf mRNA was detected in the hepatic primordia. This is the first observation pointing out Tf as an early marker of hepatic differentiation, prior to the formation of the liver. Thus, TF may be an important tool to follow the hepatic specification of the gut endoderm. Mouse Tf mRNA was also detected in the liver bud and subsequently in the liver throughout fetal life, and in newborn and adult animals. No expression of the Tf gene was observed in the mouse fetal central nervous system (CNS). In contrast, Tf mRNA was detected from the 5th day after birth in the derivatives of the caudal part of the neural tube and subsequently in the derivatives of the rhomboencephalon and that of the prosencephalon. These results indicate that Tf gene expression correlates with the postnatal development of oligodendrocytes in the mouse CNS. To test whether the control elements of the human gene previously found in ex vivo experiments were also active in vivo during fetal and adult life, we fused the -4000/+395' flanking region of the human gene to the coding region of the lacZ gene and generated transgenic mice. The expression of the reporter gene during development was analyzed. PMID- 9364328 TI - Distribution of metabotropic glutamate receptor type 1a in Purkinje cell dendritic spines is independent of the presence of presynaptic parallel fibers. AB - The metabotropic glutamate receptor type 1a (mGluR1a) is expressed at a high level in the molecular layer of the cerebellar cortex, where it is localized mostly in dendritic spines of Purkinje cells, innervated by parallel fibers. Treatment with methylazoxymethanol (MAM) of mouse pups at postnatal days (PND) 0 + 1 or 5 + 6 results in the partial loss of granule cells, the extent of which depends on the age of the animal at the time of injection. As a consequence of hypogranularity, the number of parallel fibers is decreased to such an amount that many of the postsynaptic Purkinje cell dendritic spines are devoid of axonal input, and only a limited number of spines participate in the formation of parallel fiber synapses, or, infrequently, in heterologous or heterotopic synapses with other presynaptic partners. At PND 30, 50% of the spines in the cerebella of mice treated with MAM at PND 0 + 1 was not contacted by any presynaptic element, compared to 5% in controls or 15% in the cerebella of mice treated with MAM at PND 5 + 6. The localization of mGluR1a was visualized by immunocytochemistry on ultrathin sections: approximately 80% of all Purkinje cell dendritic spines were immunopositive in controls and in both groups of MAM treated mice, indicating that mGluR1a was present in Purkinje dendritic spines even when the corresponding synaptic input was absent. This observation indicates that the expression and subcellular distribution of mGluR1a are inherent, genetically determined properties of Purkinje cells. PMID- 9364329 TI - Short-term response of postnatal rat vestibular neurons following brain-derived neurotrophic factor or neurotrophin-3 application. AB - The effects of the application of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) neurotrophins on the intracellular calcium level ([Ca2+]i) were studied in vestibular ganglion neurons (VGNs) from postnatal day 3 (P3) rats cultured for 50 hr. We first assessed the expression of trkB and trkC mRNA receptors in cultured VGNs. Immunobloting and immunocytochemistry confirmed the presence of the neurotrophin receptors on neurons. Both neurotrophins induced transient [Ca2+]i elevations in VGNs: BDNF-treated neurons responded in 65% and NT-3-treated neurons in 56%. The responses could be inhibited by anti-BDNF or anti-NT-3 antibodies. The [Ca2+]i elevation was dependent on extracellular calcium since it was abolished in calcium-free medium but also implicates the release of calcium from intracellular stores as tested by prior depletion with thapsigargin. Our results suggest the implication of a short-term calcium regulation in VGNs, which could reflect specific fast effects of neurotrophins in the early postnatal rat vestibular system. PMID- 9364330 TI - Nitric oxide inhibits the dopamine-induced K+ current via guanylate cyclase in Aplysia neurons. AB - Nitric oxide (NO) is produced by the enzyme nitric oxide synthase (NOS) and has been implicated in inter- and intracellular communication in the nervous system. The present study was undertaken to assess the effects of sodium nitroprusside (SNP) and hydroxylamine (HOA), NO donors, on a dopamine (DA)-induced K+ current in identified Aplysia neurons using voltage-clamp and pressure ejection techniques. Bath-applied SNP (10-25 microM) reduced the DA-induced K+ current without affecting the resting membrane conductance and holding current. The DA induced K+ current also was inhibited by the focal application of 200 microM HOA to the neuron somata. The DA-induced K+ current suppressing effects of SNP and HOA are completely reversible. Pretreatment with 1H-[1,2,4]oxadiazolo[4,3 a]quinoxalin-1-one (ODQ; 1 microM), a specific inhibitor of NO-stimulated guanylate cyclase, and hemoglobin (50 microM), a nitric oxide scavenger, decreased the SNP-induced inhibition of the DA-induced current. In contrast, intracellular injection of 1 mM guanosine 3',5'-cyclic monophosphate (cGMP) or bath-applied 3-isobutyl-1-methylxanthine (IBMX; 50 microM), a non-specific phosphodiesterase inhibitor, inhibited the DA-induced current, mimicking the effect of the NO donors. These results demonstrate that SNP and HOA inhibit the DA-induced K+ current and that the mechanism of NO inhibition of the DA-induced current involves cGMP-dependent protein kinase. PMID- 9364331 TI - Characterization of rat brain kynurenine aminotransferases I and II. AB - The endogenous neuroprotectant kynurenic acid (KYNA) is produced by irreversible transamination of L-kynurenine (KYN). In the brain, two distinct kynurenine aminotransferases (KAT I and KAT II) are responsible for the formation of KYNA. The present experiments were designed to examine the respective roles of the two KATs in the normal rat brain. To this end, the two enzymes were partially purified, and their characteristics were examined. KAT I (identical with glutamine transaminase K) had an optimal pH of 9.5, preferred pyruvate as a cosubstrate and was potently inhibited by glutamine. KAT II (identical with L alpha-aminoadipate transaminase) had a neutral optimal pH, showed no preference for pyruvate, and was essentially insensitive to inhibition by glutamine. KAT II was selectively inhibited by quisqualic acid (IC50: 520 microM). The endogenous substrate 3-hydroxykynurenine had an approximately 10-fold preference for KAT II. The distinct properties of the two enzymes made it possible to measure brain KAT I and KAT II in parallel by using dialyzed tissue homogenate (to remove interfering endogenous amino acids). Under these conditions, both enzymes presented essentially the same apparent Km values as the partially purified enzymes. In lesioned, neurondepleted brain tissue and in brain regions other than the cerebellum, KYNA derived primarily from KAT II at physiologic pH. In summary, the present study describes a simple methodology for the simultaneous determination of the two KYNA-producing enzymes in small rat brain tissue samples and provides baseline values for future work in experimentally challenged animals. PMID- 9364332 TI - Myelin contains neutral sphingomyelinase activity that is stimulated by tumor necrosis factor-alpha. AB - Purified myelin from mouse brain was found to contain two forms of neutral sphingomyelinase, one Mg2+ dependent and the other Mg2+ independent. The former had a pH optimum of 7.5 and Km of 0.35 mM, whereas the corresponding values for the latter were pH 8.0 and Km 3.03 mM. Specific activity of the Mg(2+)-dependent enzyme showed a rostral-caudal gradient, ranging from 75 nmol/mg protein/hr in myelin from cerebral hemispheres to 21 nmol/mg protein/hr in myelin from spinal cord. Relative specific activity was approximately 20% that of brain stem or cerebral hemisphere homogenate. Treatment of myelin with taurocholate or high salt concentration did not significantly reduce activity of the Mg(2+)-dependent enzyme. The activity of that enzyme did not change with time or in the presence or absence of protease inhibitors; by contrast, that of Mg(2+)-independent enzyme decreased sharply in the absence of protease inhibitors but rose in their presence. To test for the effect of tumor necrosis factor-alpha (TNF alpha) on myelin sphingomyelinase, mouse brain myelin was labeled in vivo by intracerebral injection of [3H]acetate into 18-20-day-old mice. After 40 hr, brain stems were removed, minced, and treated with TNF alpha in Krebs-Ringer solution, after which myelin was immediately isolated. Separation and counting of individual lipids revealed TNF alpha treatment to cause increased labeling of myelin ceramide and cholesterol ester with concomitant decrease in myelin sphingomyelin. Western blotting of myelin proteins using antibodies to the two TNF alpha receptors as probes revealed the presence of the p75 receptor. Implications of these findings in relation to possible mechanisms of autoimmune demyelination are discussed. PMID- 9364333 TI - Microglia and astroglia have a common progenitor cell. AB - Disaggregated neopallial cells from newborn C3H/HeJ mice were cloned in Grenier hybridoma tissue culture dishes, and culture wells that contained only one cell were marked. After 8-10 days of culturing, the cultures were fixed and double immunolabeled for microglia with Mac-1 antibody and for astroglia with antibody to GFAP. Each marked well containing a clone was identified as either a microglia, astroglia, mixed microglia-astroglia, or an unlabeled clone. The effect of LM cell line conditioned medium (LM-CM), which contains colony stimulating factor-1, on the development of mixed microglia-astroglia clones was determined. Formation of mixed clones was dose dependent (P < 0.0001). We concluded that microglia and astroglia have a common progenitor cell and that the development of mixed clones is LM-CM dependent. PMID- 9364334 TI - Functional significance of recoverin localization in multiple retina cell types. AB - Knowledge of the cellular localization of recoverin in photoreceptor cells has enabled its interaction with other proteins to be postulated, tested and verified. Recoverin, a calcium sensing protein, is now thought to act by prolongation of the light state through interference with the interaction of arrestin and rhodopsin. Because of the detection of recoverin in multiple cell populations, the specificity of the cellular localization of recoverin was investigated in the retina of the mouse, rat, rabbit, chicken, frog, and chameleon and compared to that for opsin, phosducin, and arrestin. In addition to photoreceptor cell staining, the application of affinity-purified antibodies against recoverin demonstrated immunoreactive cells in the inner nuclear layer and a rare immunopositive cell in the ganglion cell layer of the mouse, rat and rabbit retina. Only photoreceptor cells were stained with recoverin antibodies in the chameleon and frog retina, whereas no cells were recoverin-positive in the chicken retina. In all six species studied, only photoreceptor cells were labelled with antibodies against opsin, phosducin or arrestin. Based on intensity of staining, two distinct populations of anti-recoverin-immunoreactive cells were distinguished in the photoreceptor cell layer of the retinas of the rat and rabbit, with the more darkly stained cells (probably cones) representing about 3% of the photoreceptor cells. The presence of recoverin in cells other than photoreceptors suggests it has an alternative or additional function and indicates the presence of multiple cell type-specific expression signals in the regulatory region of the recoverin gene. PMID- 9364335 TI - Specificity of neurotrophin-3 determined by loss-of-function mutagenesis. AB - Neurotrophin-3 (NT-3) is a member of the family of neurotrophic factors, which also includes nerve growth factor (NGF) and which have specific activities on different subsets of vertebrate neurons. The aim of this study was to determine which residues in NT-3 direct its specificity to the cognate TrkC receptor. It was possible to replace 80% of the residues in NT-3 with NGF residues without loss of specific activity. Residues D72, Y85, R87, W101, S107, and A111, together with either the residues F12, V18, V20, M37, V42, F54, and K57 or the variable regions IV and V, accounted for the specificity of NT-3. It is concluded that NGF and NT-3 use overlapping as well as separated regions for determination of specificities for their cognate receptors TrkA and TrkC, respectively. PMID- 9364336 TI - Evaluation of the clinical utility of the ultrasensitive immunofluometric assay for growth hormone (GH) and of the cortisol secretory pattern in prediction of the linear growth response to treatment with GH. AB - OBJECTIVES: To evaluate the utility of an ultrasensitive IFMA for human 22 kDa GH in assessment of GH secretion and prediction of the linear growth response to exogenous GH. METHODS: Utilizing Delfia reagents supplied by Wallac-OY, an ultrasensitive IFMA for GH was established. Serum GH concentrations from 15 children/adolescents undergoing 24 hour GH secretory profiles with sampling at 20 minute intervals were analyzed by both IFMA and RIA. Cortisol values were also measured. Twelve children were later treated with GH. The 24 hour GH and cortisol secretory profiles were analyzed by the Cluster program and the relationships of these profiles to the linear growth response to exogenous GH determined. RESULTS: The sensitivity of the IFMA for GH relative to a zero standard was 0.005 ng/ml; intra-assay coefficients of variation ranged from 12% at a GH concentration of 0.005 ng/ml to 4% at 0.038 ng/ml; interassay coefficients of variation ranged from 34% at a GH concentration of 0.005 ng/ml to 10.5% at 2.7 ng/ml and to 2.7% at 12.7 ng/ml. Above assay sensitivity, there was good correlation between GH concentrations determined by IFMA and those by IRMA and RIA (r = 0.998 and 0.992 respectively). The number of GH secretory peaks identified by IFMA was significantly greater than that detected by RIA (10.6 +/- 3.2 [SD] vs 6.7 +/- 3.3/24 hours, p = 0.0001 by paired t-test). There were few significant relationships between any parameter of GH secretion measured by RIA or IFMA (peak GH pulse amplitude, percent increase in amplitude, area under the peak, interpeak interval) and the pretreatment growth rate, the growth velocity while receiving GH therapy, or the increment in growth rate during administration of GH. The number of GH secretory peaks determined by RIA correlated weakly with the pretreatment growth rate. There was no meaningful relationship between the serum concentrations of cortisol and GH-IFMA. Peak GH concentrations and nadir cortisol values were exactly coincident in 15.7% (25/159); 42.8% of nadir cortisol values coincided with or were within +/- 20 minutes of peak GH values (68/159). However, there was no relationship between the number of cortisol secretory peaks, the pooled 24 hour and nocturnal concentrations of cortisol and the pretreatment growth velocity, the growth rate or increment in growth velocity during administration of GH. CONCLUSIONS: Despite the increased sensitivity of the IFMA and its ability to detect pulsatile GH secretion heretofore unidentified, data from this GH assay were not useful in predicting first year growth rate during administration of GH. The secretory pattern of cortisol was not helpful in predicting the growth response to GH. PMID- 9364337 TI - Increase in bone density and plasma osteocalcin during growth hormone therapy in growth hormone deficient children. AB - Bone density in growth hormone (GH) deficient children is decreased more than expected for delayed skeletal maturation. Previous studies suggest GH enhances mineral retention and deposition in bone. Seven GH deficient prepubertal children were studied during 2 years of GH therapy to assess the effect on bone density and plasma osteocalcin. Bone density (radiographic photodensitometry) of the phalanges (cortical and trabecular bone) was expressed as the standard deviation score (SDS) of the mean for sex, bone age and chronological age. Relative osteopenia, less pronounced for bone density/bone age (BD/BA) than bone density/chronological age (BD/CA), improved significantly during GH therapy. After 12 months there was increase over pretreatment levels, significant for BD/CA (-1.65 +/- 0.46 vs -1.15 +/- 0.64; mean +/- SD: p = 0.002), but less pronounced for BD/BA. After 24 months increase in both measurements continued, reaching significance also for BD/BA (Pre: -1.02 +/- 0.55 vs -0.41 +/- 0.29; p = 0.011). Plasma osteocalcin levels were low before GH therapy (11.6 +/- 9.9 ng/ml; n = 7; vs control 24.4 +/- 12.5 ng/ml; n = 21; p < 0.05), rose significantly after one week (31.2 +/- 10.5 ng/ml; p < 0.001), with continued upward trend to plateau between 2-6 months, with elevated levels persisting during 2 years of GH therapy. CONCLUSION: The early and sustained rise in plasma osteocalcin and subsequent increase in bone density with continued gain over 24 months of the study suggests that GH therapy in GH deficient children has a significant prolonged effect on bone formation and mineralization in addition to stimulating linear growth. PMID- 9364338 TI - Growth hormone--insulin-like growth factor-I (IGF-I) axis in prepubertal children with chronic renal failure. AB - The hypothalamic-pituitary insulin-like growth factor I (IGF-I) axis was evaluated in 12 children with chronic renal failure (CRF) aged 3.2 to 16.5 yr (mean 9.5) on chronic dialysis, and in 13 renal transplantation patients aged 7.5 to 15.0 yr (mean 11.1). Height standard deviation score (SDS) was -2.8 +/- 0.5 (mean +/- SE) and -3.0 +/- 0.3 SDS (p = NS), and growth velocity was 3.7 +/- 0.4 and 1.5 +/- 0.3 cm/year (p < 0.01), respectively. Mean nocturnal growth hormone (mean GH) and number of pulses > 5 ng/ml in CRF and transplantation children were 4.2 +/- 0.8 vs 2.4 +/- 0.3 ng/ml, p = 0.08 and 1.7 +/- 0.2 vs 1.0 +/- 0.2, p < 0.05, respectively. In transplant children there was a positive correlation between mean GH and growth velocity (p < 0.02). GH peak response and the area under the curve post GH releasing hormone test were significantly higher in CRF and transplant children treated with deflazacort (new steroid derived from prednisolone) vs transplant children treated with methylprednisone. Mean serum IGF-I levels were -0.5 +/- 0.2 SDS for chronological age (CA) in CRF patients and +0.8 +/- 0.2 SDS(CA) in transplant patients, p = NS. In the latter, serum IGF-I values were positively correlated with growth velocity (p < 0.02) and negatively correlated with methylprednisone dose (p < 0.05). CONCLUSIONS: Patients with CRF and growth retardation have a higher number of GH peaks and slightly elevated mean GH levels compared to transplant patients. After renal transplantation GH secretion may be influenced by glucocorticoids as shown by the lower GH response to GHRH which improved with deflazacort and the inverse correlation between methylprednisone dose and IGF-I levels. PMID- 9364339 TI - Factors predictive of response to growth hormone therapy in Turner's syndrome. AB - In Turner's syndrome there is marked heterogeneity of growth response to growth hormone (GH) therapy. The study aim was to identify pretreatment factors that influence response to GH therapy. The 70 subjects recruited were prepubertal, had not received sex steroids and had received 28 units/m2/week of GH for > or = 1 year. Pretreatment variables associated with the greatest improvement in height SDS (r2 = 0.58) were weight for length index (p = 0.0001), target height (p = 0.004), bone age delay (p = 0.008) and age (p = 0.04). In conclusion, during two years of GH therapy the best growth response occurred in girls who were younger, heavier, had a delayed bone age and tall parents. Height SDS as a continuous variable is the most effective measure of growth when considering pretreatment factors that may influence response to GH therapy. PMID- 9364340 TI - Growth hormone release by the novel GH releasing peptide hexarelin in patients with homozygous beta-thalassemia. AB - Patients with beta-thalassemia often present with abnormalities in growth and other endocrine functions. Growth hormone (GH) secretion is controlled via somatostatin and growth hormone releasing hormone (GHRH). Recently, Hexarelin, a new potent GH secretagogue (His-D-2-Methyl-Trp-Ala-Trp-D-Phe-Lys-NH2), was synthesized. Our study was designed to assess and compare its efficacy as a GH secretagogue to GHRH 1-29 in beta-thalassemia. Eighteen patients, regularly transfused and chelated, were studied; 11 were short statured. None had diabetes mellitus, hypothyroidism, hypopara-thyroidism or major organ failure. We measured GH at 0, 30, 60, 90, 120 min after GHRH 1-29 or Hexarelin administration. Hexarelin p.o. or i.v. evoked a brisk rise of serum GH which was significantly higher (p < 0.01) than that induced by GHRH 1-29 i.v. In conclusion, Hexarelin has greater GH releasing capacity than GHRH 1-29 at 1 microgram/kg i.v. and can thus be viewed as a potential therapeutic agent in GH deficient states. PMID- 9364341 TI - Growth hormone treatment in irradiated children with brain tumors. AB - We assessed the efficacy of GH treatment in 25 GH deficient patients irradiated for brain tumors (eight with glioma cranio-irradiated, eleven with medulloblastoma and six with ependymoma craniospinal-irradiated). We administered GH at doses of 0.6-0.9 IU/kg/week for one to three years at least two years after diagnosis of the tumor. We assessed the efficacy of the treatment each year by comparing the values of height velocity over bone age and change in the ratios progression of chronological age/progression of bone age and progression of statural age/progression of bone age. The treatment promoted satisfactory growth; better results were obtained in patients with glioma, who received cranial irradiation only, than in those with medulloblastoma or ependymoma, who received spinal irradiation as well. Moreover, the growth prognosis improved, especially in the cranio-irradiated patients. In our series of patients four presented tumor recurrence; these results did not differ significantly from those in irradiated patients with cerebral tumors who were not treated with GH. PMID- 9364342 TI - Vitamin A and beta carotene levels in constitutional delay of growth and puberty. AB - The objective of this study was to investigate the vitamin A (vit A) status and beta carotene levels of children with constitutional delay of growth and puberty (CDGP). Serum vit A and beta-carotene levels of 26 children with CDGP were measured. 20 age-matched healthy children with normal pubertal development served as controls. Except for the height SDS, which was significantly lower in the CDGP group (p < 0.05), no significant differences were found between chronological ages, weight for height indices and beta-carotene levels of the two groups (p > 0.05). Although serum vit A levels of children in both groups were within normal limits according to WHO criteria, serum vit A levels were significantly lower in the CDGP group than in controls (44.13 +/- 12.25 and 59.60 +/- 19.75 micrograms/dl respectively, p < 0.05). It was concluded that vit A deficiency may play a role in CDGP in developing countries. PMID- 9364343 TI - Mutations of the steroid 21-hydroxylase gene in an Argentinian population of 36 patients with classical congenital adrenal hyperplasia. AB - In several studies carried out in USA and Europe, gene deletions, large gene conversions and six point mutations accounted for over 90% of the mutated alleles reported in classical congenital hyperplasia (CAH). In order to know the relative frequencies of mutations in a Latin-American population, the CYP21 active gene was analyzed in 42 patients with CAH belonging to 36 families attending two Argentinian clinics. The salt wasting form was diagnosed in 24 index cases and the simple virilized form in 12. When available, parents were also studied. DNA was extracted from peripheral blood leukocytes and specific PCR amplification of four different fragments of the CYP21 gene was carried out, followed by electrophoresis of the amplified product. The four fragments include segments of the gene containing the six most frequently reported abnormalities in classical CAH: IN2, EX3, R356W, cluster EX6 and I172N. Point mutations were studied by allelic specific oligonucleotide hybridization; Q318X was studied by digestion of the PCR product with PsT1 restriction enzyme and electrophoresis on 6% non denaturing polyacrylamide gels. Deletions and macroconversions as well as confirmation of homozygote point mutations were studied by Southern blotting. Percentage distribution of abnormalities was as follows: deletion/macroconversion 18, IN2 18, I172N 15.3, Q318X 13.8, R356W 5.5, EX3 2.7, cluster EX6 0, not characterized 26.7. The complete genotype could be determined in 20 families while in 12 additional ones, the mutation was detected in one allele. Deletion/macroconversion, IN2, EX3 and Q318X were detected more frequently in salt wasting patients while I172N and R356W were found in simple virilized patients. However, genotype was not always concordant with phenotype. It is concluded that there are differences in the frequency of several gene mutations and in that of deletion/macroconversion between this Latin-American population and several reported American and European populations. In particular the percentage of deletion/macroconversion, IN2, EX3 and cluster EX6 was lower while I172N was higher in our Latin-American population. Furthermore the frequency of mutations not characterized was larger. This information is useful to delineate appropriate strategies for prenatal diagnosis in this particular population. PMID- 9364344 TI - Maturity-onset diabetes of the young (MODY): three case reports and new perspectives. AB - Maturity-onset diabetes of the young (MODY) is a rare form of juvenile diabetes mellitus that presents with hyperglycaemia in the absence of ketosis. We present three cases of MODY, all of whom had pedigrees with diabetics in multiple generations. All our patients presented in adolescence with evidence of insulin resistance. Two patients were relatively overweight. All three patients were readily controlled on diet alone. None had any clinical evidence of diabetic complications in early adulthood. Recently there has been a marked increase in our understanding of MODY. Genetic linkage and mutational analyses have identified three subtypes (MODY1, 2 and 3) that are all transmitted in an autosomal dominant fashion. The pathophysiology of the MODY subtypes is variable with both increased and decreased insulin levels being seen. A failure to recognise MODY will result in a lack of appropriate therapy and the potential for diabetic complications. PMID- 9364345 TI - Growth hormone deficiency in autoimmune polyglandular syndrome. AB - We describe a boy with autoimmune adrenal failure and compensated hypothyroidism, associated with isolated growth hormone deficiency (GHD). We suggest an autoimmune mechanism as the underlying etiology for the GHD in this case. PMID- 9364346 TI - A case of isolated growth hormone (GH) deficiency with compound heterozygous abnormality at the GH-1 gene locus. AB - We report a Japanese boy with IGHD who is a compound heterozygote at the GH-1 gene locus. The patient and his mother were heterozygous for a 6.7 kb deletion of the GH-1 gene. A T-->C transition at position -123, an A-->G transition at position -6 and an A-->T transition at position -1 in the GH-1 promoter region and the addition of AGAA at base 250 in intron I were observed in one allele of the patient and his father. These results demonstrate that familial IGHD is a heterogeneous disease that perturbs different steps in the expression of the GH-1 gene. PMID- 9364347 TI - Hashimoto's thyroiditis and mixed connective tissue disease in an 11 year-old girl. PMID- 9364348 TI - Long-term diazoxide treatment in persistent hyperinsulinemic hypoglycemia of infancy: a patient report. AB - Long-term diazoxide and somatostatin analogue have been used in the treatment of persistent hyperinsulinemic hypoglycemia of infancy albeit with some side effects. We report a case with persistent hyperinsulinemic hypoglycemia who has been on diazoxide therapy for 4.5 years. Diazoxide treatment maintained normoglycemia without causing any side effects, including hypertrichosis. PMID- 9364349 TI - Genetics of the growth hormone axis. PMID- 9364350 TI - Growth, puberty and endocrine function in beta-thalassaemia major. AB - Although delay in onset of puberty is a common cause of growth failure in adolescent thalassaemic patients, growth retardation could also be due to iron overload, the toxic effects of desferrioxamine, or the development of other endocrinopathies such as GH insufficiency or primary hypothyroidism. Abnormal body proportions with truncal shortening are commonly seen and could be due to the disease itself, iron toxicity, delay in puberty or the toxic effects of desferrioxamine. The absence of a pubertal growth spurt during spontaneous or induced puberty is detrimental to the achievement of a normal final adult height. Low serum IGF-I and normal GH reserve in short thalassaemic children imply that a state of relative GH resistance exists. The rise in IGF-I and improvement in growth with GH therapy suggest that this GH resistance is only partial. Although the results of short-term GH therapy are encouraging, the impact of treatment on final height of non-GH deficient short thalassaemic children remains uncertain. Multiple endocrinopathies, including hypogonadism, hypothyroidism and diabetes mellitus, occur mainly in older patients who tend to have high serum ferritin levels. Prognosis for survival is greatly improved if the serum ferritin is kept below 2000 micrograms/l by regular chelation. Chelation therapy initiated early before the accumulation of a significant iron burden or dosages of desferrioxamine in excess of 50 mg/kg/day should be avoided. Serum ferritin should be checked regularly and the "toxicity index" should be used to monitor chelation therapy. In cases of delayed puberty, sexual development should be induced at an appropriate age. PMID- 9364351 TI - Molecular diagnosis and endocrine evaluation of a patient with a homozygous 7.0 kb deletion of the growth hormone (GH) gene cluster: response to biosynthetic GH therapy. AB - A significant proportion of cases of GH deficiency (5-30%) may be due to genetic causes. At least four Mendelian types of isolated GH deficiency (IGHD) have been delineated based on the mode of inheritance and the degree of GH deficiency, with IGHD type IA being the most severe. A 2 year-old girl, the second child of consanguineous parents, with short stature was diagnosed with IGHD type IA. The analysis of the genomic DNA of this patient, performed by polymerase chain reaction (PCR) amplification of the flanking regions of the GH-1 gene, showed a homozygous deletion of 7.0 kb of sequence including the GH-1 gene. She was treated with biosynthetic GH resulting in long-lasting catch-up growth during at least three years, despite a clinically irrelevant appearance of low binding capacity GH antibodies. Growth hormone-binding protein (GHBP) levels were normal at the time of diagnosis. In addition, GHBP plasma levels did not show any significant change during the three years of therapy with GH. Diagnosis of carrier status in family relatives was done by genotyping GH gene alleles by PCR amplification from blood spots on filter paper. PMID- 9364353 TI - Growth hormone treatment in growth retarded children with end stage renal failure: effect on free/dissociable IGF-I levels. AB - Growth retardation in children with endstage renal disease (ESRD) is associated with normal to slightly low concentrations of insulin-like growth factor (IGF)-I and increased concentrations of IGF-binding proteins (IGFBPs) in serum. Consequently, IGF-I bioactivity is reduced in serum from uremic patients presumably due to a decrease in the concentration of free IGF-I. Improvement of linear growth with growth hormone (GH) treatment of uremic children is thought to be due to increased IGF-I/IGFBP ratio, thus resulting in increased free IGF-I levels during treatment. The purpose of the present study was to determine whether free/dissociable IGF-I levels are in fact low in uremic children and whether increased growth velocity during GH treatment is associated with an increase in the free IGF-I concentration. Serum total and free/dissociable IGF-I concentrations were measured in 5 children with ESRD before and during treatment with GH, and in control children matched for age, pubertal status, and body mass index. Height velocity increased from 3.7 +/- 1.0 cm/yr to 6.5 +/- 1.2 cm/yr with an increment in height SDS at the end of the first year of GH treatment. Free/dissociable IGF-I concentrations tended to be lower in uremic children compared to control children (3.0 +/- 0.3 vs 7.3 +/- 2.1 micrograms/l, respectively). During GH treatment, free/dissociable IGF-I levels increased significantly to 8.5 +/- 1.0 micrograms/l at 3 months and 6.9 +/- 1.4 micrograms/l at 6-24 months, p < 0.05 compared to pretreatment. Total IGF-I levels were 243 +/- 18 micrograms/l in children with ESRD before treatment and these values also increased during GH treatment (740 +/- 114 micrograms/l at 3 months and 442 +/- 44 micrograms/l at 6-24 months, p < 0.05, compared to pretreatment). Total IGF-I concentration in the control group was 439 +/- 114 micrograms/l. These results support the hypothesis that growth retardation in children with chronic renal failure is associated with a reduction in the concentration of free, biologically available IGF-I, and that increased growth velocity during GH treatment of these children is associated with restoration of free IGF-I concentrations. PMID- 9364354 TI - Incidence of insulin dependent diabetes mellitus in Greek Cypriot children and adolescents, 1990-1994. AB - Insulin dependent diabetes mellitus (IDDM) is one of the most common chronic diseases among children and adolescents worldwide. It has been well established that there are marked geographic differences in the incidence of IDDM, which may provide important clues concerning its as yet unknown etiology. The objective of this study was to estimate the incidence of IDDM in the Greek population of Cyprus based on epidemiological data collected during the period 1990-1994. The results of this survey showed that the incidence of IDDM in the Greek population of Cyprus is 10.5/100,000 population under the age of 15 years, which is in agreement with other European countries. There was a slight increase in the number of newly diagnosed patients in 1994. The mean age of onset is 8 years whereas the peak age of onset occurs at 11-12 years. There is a slight overall female predominance but not among children who manifest IDDM before the age of five years in whom males significantly predominate. Distribution by month of onset of IDDM revealed an increased number of cases during autumn and winter as expected. PMID- 9364355 TI - Albumin excretion rate, serum insulin-like growth factor-I and glomerular filtration rate in type I diabetes mellitus at puberty. AB - The albumin excretion rate (AER), insulin-like growth factor-I (IGF-I) levels, glomerular filtration rate (GFR) and glycosylated hemoglobin (HbA1c) levels were studied in 49 diabetic children and 49 controls. The duration of diabetes varied from newly diagnosed to 17.5 years. Diabetics exhibited a wide range of AER values and had significantly higher AER and IGF-I levels compared to controls. At puberty elevated circulating growth hormone (GH) concentrations were found with a parallel increase in the levels of IGF-I. High IGF-I levels were found in 10-12 year-old girls and 15-16 year-old boys in both diabetic and control groups. Positive correlations were found between IGF-I and GFR in girls of both groups (p < 0.05) and in control girls between IGF-I, GFR and microalbuminuria (p < 0.05). The diabetic boys also showed microalbuminuria with respect to controls at high HbA1c levels and when their testis volume exceeded 8 ml (p < 0.05). We concluded that the prominent change in GH release at puberty, reflected by IGF-I, is in pulse amplitude, and that this is increased in diabetes but it is not a very important factor when determining the abnormal levels of urinary albumin excretion. PMID- 9364352 TI - Growth during and 2 years after stopping GH treatment in prepubertal children with idiopathic short stature. AB - Forty-six prepubertal children with idiopathic short stature (ISS), 39 boys and 7 girls, with a mean age of 7.4 +/- 1.8 (SD) years, and mean bone age of 4.5 +/- 1.5 years were treated by human growth hormone (GH) 0.1 U/kg/day s.c. for 30.5 +/ 16.2 months (M +/- SD) (2-5 years range) and were followed for 1-2 years after stopping GH. The mean net gain in height at the end of treatment was 1.03 +/- 0.6 SDS and the bone age SDS was accelerated by 0.95 +/- 1.05. Despite a transitory "catch-down" in growth velocity after stopping GH administration, there was a mean height gain at the end of 2 years follow-up of 0.87 SDS. Children who started treatment before age 6.5 benefited more than older ones. In conclusion, the gain in height observed in children with ISS by GH treatment was maintained during 2 years of follow-up after interruption of treatment. Even if this benefit is transitory and not permanent, it may help short children to achieve self confidence and raise their physical performance at the critical period of school entry. PMID- 9364356 TI - Congenital hypothyroidism and concomitant anomalies. AB - To search for concomitant anomalies among babies with congenital hypothyroidism, 120 newborn babies with confirmed congenital hypothyroidism were studied at the Veterans General Hospital, Taipei. The incidence of concomitant anomalies was estimated to be 11.67% (14/120). Among these anomalies, cardiac and gastrointestinal systems were the most commonly involved, comprising 35.7% (5/14) and 28.6% (4/14) of all anomalies, respectively. The type (i.e. agenesis, ectopia or eutopic goiter) as well as the severity of hypothyroidism were analyzed between groups of babies with or without concomitant anomalies. No differences existed between the two groups of babies regarding these two aspects. PMID- 9364357 TI - Successful intravenous desensitization of growth hormone hypersensitivity. PMID- 9364358 TI - Adrenocortical adenoma--an unusual presentation with hypersecretion of oestradiol, androgens and cortisol. AB - We describe a 6 year-old boy who presented with bilateral gynaecomastia, pseudoprecocious puberty and facial features suggestive of Cushing's syndrome. The underlying pathology was a right adrenocortical adenoma which was secreting oestradiol, androgens and cortisol. All the biochemical abnormalities normalised within one week of right adrenalectomy. To our knowledge this combination of hormones produced by an adrenocortical adenoma is particularly unusual. PMID- 9364359 TI - Combined cabergoline and recombinant human growth hormone treatment of an adolescent with a macroprolactinoma causing GH deficiency. AB - The rare macroprolactinomas seen in childhood frequently cause delayed puberty and GH deficiency. We report the combined use of cabergoline and recombinant human GH (rhGH) therapy in a male adolescent with macroprolactinoma and GH deficiency. Computed tomography and magnetic resonance imaging of the hypothalamic-pituitary region showed a macroadenoma with extrasellar extension. Neither bromocriptine nor dihydroergocryptine therapy was successful in decreasing serum PRL levels. On cabergoline treatment normal serum PRL levels were achieved within 3 months along with a marked shrinkage of the adenoma but growth rate did not increase nor did puberty start. The addition of exogenous rhGH therapy improved the growth rate, but complete pubertal development was obtained only after the administration of exogenous gonadotropins. During the combined treatment no expansion of the macroadenoma was observed. In conclusion, the combined therapy with cabergoline and rhGH seems to be safe and highly effective. Nevertheless, it warrants careful monitoring and on-going evaluation. PMID- 9364360 TI - Recovery from metabolic bone disease in a girl with vitamin D deficiency rickets associated with primary hyperparathyroidism. AB - We describe a 13 year-old Ethiopian girl with vitamin D deficiency rickets. Hypercalcemia, increased serum alkaline phosphatase and PTH levels, together with low serum levels of 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D suggested the co-existence of primary hyperparathyroidism. The surgical removal of a parathyroid adenoma led to bone healing and normalization of blood chemistry. We conclude that vitamin D deficiency masked the hyperparathyroidism and hypercalcemia, while excess PTH secretion delayed the cure of rickets until successful parathyroidectomy had been carried out. PMID- 9364361 TI - Growth hormone treatment of children with chronic renal insufficiency, end-stage renal disease and following renal transplantation--update 1997. AB - 1. Long-term (> 5 years) hGH treatment in children with CRI produces sustained improvement in standardized height. 2. hGH treatment of infants (< 2 1/2 years of age) with CRI is as effective at improving growth velocity as in older children with CRI. 3. Once target height (50th percentile for midparental height) is reached the optimal approach is to pause hGH treatment and observe the patient. If standardized height declines significantly, hGH is effective when re initiated. 4. Neither short-term nor long-term hGH treatment in children with CRI or in pediatric allograft recipients adversely impacts on carbohydrate tolerance; however, hyperinsulinemia develops which has not been associated with any clinical consequences to date. 5. The presence of renal osteodystrophy may blunt the impact of hGH and predispose to development of slipped capital femoral epiphysis and/or avascular necrosis in children with CRI. Pre-treatment radiologic evaluation and radiologic surveillance with clinical symptoms is indicated. 6. hGH is effective during the initial year of treatment; however the response may be blunted during subsequent years of treatment. The precise mechanism of the latter has not been delineated. 7. hGH has been shown to improve growth velocity in patients undergoing both peritoneal and hemodialysis; however, long-term data are lacking and the response may be less than that achieved in patients with CRI. 8. Growth velocity is uniformly improved in growth retarded pediatric renal allograft recipients receiving hGH. 9. Allograft dysfunction occurs following hGH treatment; however, the relationship to hGH treatment requires delineation. 10. The mechanism responsible for early allograft dysfunction which is usually reversible upon discontinuation of hGH is unknown. 11. Risk factors for the development of an acute rejection episode during the course of hGH treatment are > 1 prior rejection episode and the use of alternate day corticosteroid therapy. 12. The potential exists for an accelerated decline in allograft function following hGH treatment in recipients with chronic rejection. 13. The salutary effect of hGH in this patient population is probably related to increasing the bioavailability of ("free") IGF-I. PMID- 9364363 TI - Age-related differences in serum insulin-like growth factor-I (IGF-I) and IGF binding protein-3 levels in congenital hypothyroidism. AB - It is well established that thyroid hormones play a fundamental role in normal growth and development. The complex relationship between thyroid hormone and the growth hormone-insulin-like growth factor axis is not completely understood. We investigated age-related differences in serum insulin-like growth factor-I (IGF I) and insulin-like growth factor binding protein-3 (IGFBP-3) levels in 43 patients with primary congenital hypothyroidism. These patients were classified into five age groups (Group I: 0-1 month, Group II: 1 month-1 year, Group III: 1 5 years, Group IV: 5-9 years, Group V: 9-13 years). Patients diagnosed in the first month of life did not display a significant difference in serum IGF-I and IGFBP-3 levels compared to age-matched controls (p > 0.05). However, in groups II to V, IGF-I and IGFBP-3 levels were significantly lower than in controls (p < 0.05). Thyroid hormone replacement therapy increased serum IGF-I and IGFBP-3 levels significantly in 26 hypothyroid children (p < 0.05). Although serum IGF-I and IGFBP-3 levels increase in an age dependent manner in normal children, this increment was not observed in hypothyroid children. PMID- 9364362 TI - The history of endocrinology in philately. PMID- 9364365 TI - MHC class I antigen expression in patients with IDDM and their siblings. AB - MHC class I antigen expression was found to be low on the lymphocytes of patients with insulin dependent diabetes mellitus (IDDM). Thus, it has been proposed that the defective expression of MHC antigens could lead to faulty immunological responses with the eventual destruction of the pancreatic beta cells. The objective in this study was to compare MHC antigen expression in IDDM patients and their presently healthy siblings. Nineteen children (mean age 10.8 +/- 3.9 years) with diabetes and their 25 siblings (mean age 10.7 +/- 4.6 years) were enrolled in the study. Peripheral blood lymphocytes isolated from venous blood samples were incubated with FITC conjugated monoclonal antibody W6/32. The amount of antibody binding by cell surface MHC class I antigens was assessed by flow cytometry. MHC class I molecule expression did not differ significantly among IDDM patients and their siblings. It was concluded that MHC class I antigen expression did not appear to be indicative of a susceptibility to develop autoimmune diabetes. PMID- 9364364 TI - Subnormal cortisol response to adrenocorticotropin in isolated partial 17,20 lyase deficiency. AB - We describe three male children from a Bedouin clan, two of whom are siblings, who have various degrees of incomplete virilization due to isolated 17,20-lyase deficiency. The patients have low (basal and post ACTH or hCG stimulation) plasma testosterone and androstenedione levels. An abnormally high plasma 17 hydroxyprogesterone concentration was detected. A favorable response following local testosterone administration was seen in two patients. Surprisingly, an unexplained flat cortisol response to ACTH test was also noted. Although no biochemical model can yet adequately explain the impairment in cortisol response to ACTH in these patients, it seems prudent to take this lack of cortisol response into consideration. We therefore recommend hydrocortisone supplement during moderate to severe stress. PMID- 9364366 TI - Diversity of pubertal testosterone changes in boys with constitutional delay in growth and/or adolescence. AB - In a group of 22 boys with constitutional delay in growth and/or adolescence, intermittent testosterone enanthate treatment was employed in a randomized clinical trial at multiple doses ranging from 25-100 mg every two weeks for three month periods extending over 15-21 months. Twelve of the patients displayed a prompt increase in endogenous testosterone levels during the study period, reaching levels in the adult male range (> 250 ng/dl). The remaining 10 boys showed sluggish changes in endogenous testosterone during the investigation, ranging from 35-177 ng/dl. The bone ages and testicular sizes of the two groups at study initiation did not differ though urine LH was significantly less at study entry in the slowly maturing group. The data reveal a great diversity in the pace and pattern of endogenous testosterone changes in the study population. The results also suggest that exogenous sex steroid treatment of such patients does not speed up the central nervous system processes controlling the onset and progression of puberty. Boys with delayed puberty should be followed until endogenous testosterone levels reach the adult male range in order to rule out mild gonadotropin deficits. PMID- 9364367 TI - Androgen effects on bioactive and immunoreactive gonadotrophin levels during puberty in male baboons. AB - The effect of androgens on changes in circulating LH and FSH during pubertal development was examined longitudinally in a 3 year study in male hamadryas baboons. Baboon LH and FSH were measured by a species-specific radioimmunoassay and bioactive LH (B-LH) was measured by the mouse in vitro Leydig cell bioassay. Control baboons (n = 5) progressed normally through puberty. Eight baboons were castrated prepubertally; of these four received testosterone implants at the chronological age (CA) of clinical puberty (4.0 +/- 0.1 yr, mean +/- SEM). The timing of the postcastration rise in B-LH levels ranged between 1 and 15 months later (median 3.5 months) (CA 3.5 +/- 0.2 yr) thus supporting the hypothesis that central activation of gonadotrophins occurs at the time of puberty, independent of gonadal influences. Similar results were seen for immunoreactive-LH (IR-LH) and IR-FSH levels. IR- and B-LH levels continued to rise with age (P < 0.0003) in the untreated castrated baboons, associated with an increased LH B/I ratio. Administration of testosterone resulted in temporary suppression of B-LH, IR-LH and IR-FSH levels; however gonadotrophin levels subsequently rose with age despite increased testosterone levels. Thus the mechanisms initiating puberty involve both gonad-independent events as well as alterations in negative androgenic feedback sensitivity on gonadotrophin secretion. PMID- 9364368 TI - Macroprolactinemia: a cause of hyperprolactinemia in childhood. PMID- 9364369 TI - Structural variants of chromosome 9: a possible association with hypogonadotropic hypogonadism. AB - We report two cases of structural variations of chromosome 9 associated with hypogonadotropic hypogonadism and azoospermia in adolescent boys. One patient also had a partially imperforated urethral meatus. Histological examination revealed that both had hypotrophic and underdeveloped testes. There was no LH and FSH response to LH-RH stimulation nor was there any response to naloxone tests. Basal and HCG stimulated plasma testosterone values were below normal prepubertal levels. As the administration of gonadotrophins did not improve the clinical and hormonal findings, alternative androgen therapy was necessary to achieve secondary sexual characteristics. Although they reached a good level of androgenization, their testes were still very small and azoospermia remained, as confirmed by repeated semen analyses. A possible association between chromosome 9 polymorphisms and hypothalamo-pituitary axis abnormalities is suggested. It is hypothesized that structural variants of chromosome 9 are not unrelated occurrences. Furthermore, and in view of the fact that they can lead to a high risk of azoospermia and infertility, such variants call for clinical investigation. PMID- 9364370 TI - A girl with diabetes and severe combined immunodeficiency from adenosine deaminase deficiency. AB - We present a girl with severe combined immunodeficiency (SCID) from adenosine deaminase (ADA) deficiency who developed insulin dependent diabetes mellitus (IDDM). This combination of features has not been previously reported. Because HLA typing (DQbeta-57 Asp/Asp and DQalpha-52 Ser/Ser) showed no alleles usually associated with IDDM, and ICA were repeatedly negative even after treatment with PEG-ADA and gene transplant, hypotheses on the pathogenesis of diabetes mellitus in this patient are discussed. PMID- 9364371 TI - Pseudohypoaldosteronism with pyloric stenosis--a patient report. AB - A 53 day-old infant was referred for failure to thrive and persistent vomiting with severe dehydration. He had hyponatremia and hyperkalemia. Pyloric stenosis was diagnosed by means of sonography. Poor weight gain, hyponatremia and hyperkalemia were still found after Fredet-Ramsted pyloromyotomy. A urinary tract infection, a high urinary Na+/K+ ratio, and high serum levels of aldosterone and renin were found at the second admission. Rehydration, hydrocortisone and florinef administration failed to correct hyponatremia and hyperkalemia, suggesting pseudohypoaldosteronism. This patient gained weight after treatment of his infection and salt replacement. PMID- 9364372 TI - Transient late neonatal hypocalcemia with high serum parathyroid hormone. AB - We report two patients with transient late neonatal hypocalcemia. Serum examination showed low calcium (Ca), high phosphorus, high parathyroid hormone (PTH), normal 25-hydroxyvitamin D and low or normal 1,25-dihydroxyvitamin D (1,25(OH)2vitD) levels. PTH infusion test revealed normal cyclic AMP production. In these patients, 1,25(OH)2vitD production by PTH, or Ca mobilization from bone and Ca absorption from intestine by PTH and 1,25(OH)2vitD might have been disturbed transiently due to developmental immaturities. This is a new type of transient late neonatal hypocalcemia with high serum PTH levels. PMID- 9364373 TI - Congenital rickets--a patient report. AB - We present a premature newborn with congenital rickets, born to a mother with untreated chronic renal insufficiency. X-ray films showed blurred metaphyseal ends and decreased bone density in the femurs and ribs. With treatment including calcium, phosphate, and vitamin D, her rickets healed and she grew normally. PMID- 9364375 TI - Tumor management. PMID- 9364374 TI - Five year treatment with IGF-I of a patient with Laron syndrome in Slovenia (a follow-up report). AB - This is a follow-up report of a 14 1/2 year-old boy with Laron syndrome, who received twice daily therapy with IGF-I 120 micrograms/kg for 5 years that resulted in a linear growth of 40 cm. Concomitantly he became very obese which is attributed to IGF-I action via the insulin receptors. PMID- 9364376 TI - Microvascularized free fibular grafts for reconstruction of skeletal defects after tumor resection. AB - A microvascularized free fibular graft was used to reconstruct a skeletal defect after tumor reconstruction in 13 consecutive patients. The patients were evaluated at an average follow-up of 53 months (range, 30-71). The status of each graft was evaluated for time to union, hypertrophy, functional evaluation, and complications. The average time to union was 6.5 months, and significant graft hypertrophy occurred in eight of 13 patients. Complications occurred in seven patients. Two of the 13 patients required removal of the microvascularized graft. Functional evaluation according the the Musculoskeletal Tumor Society yielded an average score of 90 (range, 83-97). The results were rated good or excellent in 11 of 13 patients, and two were rated failures. The microvascularized fibular graft provides an attractive option for the reconstruction of skeletal defects after tumor resection. The results of this procedure are especially good in skeletally immature patients. PMID- 9364377 TI - Allogeneic cortical strut for benign lesions of the humerus in adolescents. AB - Allogeneic cortical strut associated with or without cancellous bone grafting for benign adolescent humeral shaft lesions is an alternative management option offering a good chance of stabilization and healing. This study monitored 16 patients who had been treated with this surgical method from 1988 to 1993. There were nine boys and seven girls between the ages of 11 and 16 years (average, 14). Eleven patients had unicameral bone cysts; two had aneurysmal bone cysts; and three had fibrous dysplasia. All 16 patients received fresh-frozen (-70 degrees C) cortical strut inlay grafts in the humeral shaft defect after subtotal excision of the large lesions. No intramedullary rod or plate was used. The follow-up period ranged from 26 to 58 months (average, 41). There were no local recurrences or fractures of the shaft or allograft implants. The radiographs of all humeri revealed the cortical grafts to be well incorporated with new bone formation in the cavity. The overall functional results were good and excellent. This reconstruction with biologically safe and active material provided increased strength and prevented refracture. PMID- 9364378 TI - The technique for growth plate sparing in soft-tissue sarcoma around the knee. AB - Amputation in a growing child should be performed through a joint and not above or below a joint, as is commonly the case in an adult. We describe a technique for performing a through-knee amputation in a situation in which a soft-tissue sarcoma involved a leg, reaching up to the knee joint. Soft-tissue dissection was performed above the knee, leaving a safe zone from the tumor. The distal femur was dissected free of all attachments to the tibia and leg, leaving it intact but protruding from the soft-tissue sleeve of the thigh. To be able to close the stump over the protruding distal femur, the femur was shortened in the metaphysodiaphyseal area. Follow-up over 3 years shows a good through-knee stump, tumor free, and a normal distal growth plate. PMID- 9364379 TI - Embolization in the treatment of aneurysmal bone cysts. AB - Eight patients with aneurysmal bone cysts (ABC) were treated with selective embolization as an adjunct to curettage and bone graft in seven cases and as the definitive procedure in the remaining case. The age range was 5-23 years. Symptoms had been present for an average duration of 6 months. The lesions were located in the femur (three), the shoulder girdle (three), the tibia (one), and the pubis (one). Two patients had recurrent lesions, and six were primary. Average follow-up was 3 years (2-4.6 years). There were no recurrences and no complications related to embolization. All lesions ossified including the pubic lesion, which was treated with embolization alone. One patient with an ABC adjacent to the distal femoral physis had growth disturbance and a second who had an extensive acromial lesion had mild degenerative changes of the acromioclavicular joint. PMID- 9364380 TI - Acute forearm lengthenings. AB - We describe our surgical technique of acute pediatric forearm lengthening and joint leveling for treatment of symptomatic forearm-length discrepancies. A retrospective clinical and radiographic analysis was performed of all patients undergoing acute forearm lengthenings of > 1.0 cm between 1983 and 1993. Twenty four acute forearm lengthenings were reviewed with an average follow-up of 3 years. The diagnosis included osteochondromatosis in 17 patients, growth arrest in four patients, and skeletal dysplasia in three patients. Surgical indications included progressive forearm or wrist deformity, significantly limited or painful forearm rotation, or radial-head subluxation. The average lengthening was 1.5 cm (range, 1.0-2.3), which was 9% of total length (range, 3-20%). The goal for lengthening and wrist-joint leveling was near-neutral ulnar variance and was achieved in all cases. We conclude that the forearm can be lengthened acutely successfully to achieve near-neutral ulnar variance in children with forearm length discrepancies caused by osteochondromas, growth arrests, or bone dysplasias. The surgical technique and the results are described in 24 forearm lengthenings. PMID- 9364381 TI - Management of forearm deformity in multiple hereditary osteochondromatosis. AB - The records of 97 patients with multiple hereditary osteochondromatosis were retrospectively reviewed. Seventy-eight patients had one or more osteochondroma(s) of one or both forearm(s). Fifty-three operations were performed, of which 41 were excisions of symptomatic osteochondromas or dislocated radial heads. All forearm, wrist, and elbow radiographs were reviewed. Four common radiographic parameters were measured: radial articular angle, carpal slip, relative ulnar shortening, and forearm-third metacarpal angle. Thirty-seven of these 78 patients were contacted by telephone questionnaire. The results indicated that skeletally mature patients do well on a functional basis and are comfortable with their appearance, despite deformity. Surgery can improve aesthetic appearance and provide pain relief when done before or after skeletal maturity. Because of these results, we are less aggressive in the early treatment of forearm deformities. PMID- 9364382 TI - Surgical risk for elective excision of benign exostoses. AB - The surgical risk and complication rates for the elective excision of benign osteochondromas and associated surgical procedures is presented. Eighty patients had excision of 285 osteochondromas and underwent 22 other related surgical procedures. There were 10 complications in the group (12.5% per patient population); the most common were peroneal neurapraxias. Other complications included an arterial laceration, a compartment syndrome, and a fibula fracture. The surgical risk for the management of osteochondromas is low and is comparable to the risk of other related, elective procedures. However, osteochondromas should not be routinely excised unless proper indications exist for their removal. PMID- 9364383 TI - Role of MRI in diagnosis of childhood sarcoidosis with fever of unknown origin. AB - Childhood sarcoidosis is a disease with multisystem organ involvement, and initial presentation as fever of unknown origin (FUO) is relatively common. We describe herein three children (aged 9, 7, and 11 years) with sarcoidosis who were seen initially with FUO. Common clinical and laboratory features include fever of > 2 weeks' duration, weight loss, fatigue, leg pain, anemia, increased erythrocyte sedimentation rate, elevated immunoglobulin G level, negative antinuclear antibodies and rheumatoid factor, and negative purified protein derivative and Candida skin tests. Two patients had iridocyclitis, one had hilar adenopathy, and two had angiotensin-converting enzyme serum levels. All three had no evidence of pulmonary infiltrates on chest radiographs. Bone marrow biopsies for all three were normal, and with no evidence of malignancy. Plain radiographs of the lower extremities and bone scan were normal. Magnetic resonance imaging (MRI) of the lower extremities revealed intact bone architecture and multifocal nodular lesions within the marrow. Bone biopsy from the tibia performed on two patients showed normal bone trabeculae and a solitary noncaseating epithelioid cell granuloma. Noncaseating granuloma was found on reevaluation of the bone marrow biopsy in the third patient. All three patients had negative marrow stains and cultures for fungi and mycobacteria. We conclude that MRI was very useful in the diagnosis of sarcoidosis in children with FUO. PMID- 9364384 TI - Salmonella pelvic osteomyelitis in normal children: report of two cases and a review of the literature. AB - We report two cases of salmonella osteomyelitis isolated to the pelvis in white adolescents aged 12 and 16 years. No underlying medical condition predisposed these children to salmonella osteomyelitis, and the clinical course was prolonged before definitive diagnosis. The key to diagnosis and the localization of the site of the pathologic condition was made from radionuclide studies performed 2-3 weeks from the onset of symptoms. Clinicians should be aware of isolated salmonella osteomyelitis of the pelvis in normal children, especially when imaging studies are normal at initial presentation. Technetium-labeled bone scans may be normal < or = 2 weeks from the onset of symptoms. Definitive diagnostic testing should include a gallium scan and computed tomography scan when technetium bone scans are negative. Treatment with antibiotics alone is successful. PMID- 9364385 TI - Acute staphylococcal osteomyelitis of the clavicle. AB - Osteomyelitis of the clavicle is a rare condition that is difficult to diagnose. We have reviewed five cases of acute staphylococcal osteomyelitis of the clavicle that have been collected over a 3-year period in our center. All patients had pain, fever, and swelling over the clavicle. All had a raised erythrocyte sedimentation rate with positive Staphylococcus aureus blood cultures at presentation. Three of our five patients required surgical drainage. Two of these patients had pathologic fracture of the clavicle while receiving treatment and then went on to develop complete resorption of the medial clavicle. Isolated reports of acute staphylococcal osteomyelitis of the clavicle in children occur in the literature. This behaves very differently from chronic sclerosing osteomyelitis and tuberculous osteomyelitis of the clavicle, which are more commonly reported. Our impression is that early treatment with high-dose intravenous antistaphylococcal antibiotics helps avoid the complication of pathologic fracture. The functional result after resorption of the medial clavicle is very good in the short term. PMID- 9364386 TI - Contiguous discitis and osteomyelitis in children. AB - Magnetic resonance imaging of 16 patients with contiguous discitis and osteomyelitis provided a specific diagnosis and defined the anatomic extent of vertebral and soft-tissue involvement. Altered signal changes were evident in the disc, adjacent vertebra in the end plate and metaphyseal equivalent regions, and the anterior prevertebral tissues. Significant posterior spread and disc herniation were not evident. Fourteen patients had lumbar involvement; two had cervical involvement. The patients were followed-up for an average of 4 years 5 months. Scoliosis has developed in one patient, and four continue to have a loss of lumbar lordosis. By comparing serial roentgenograms, the mean decrease of disc space height after the acute episode was 43% (range, 51-61%). There was no restitution of normal disc-space height at the latest follow-up roentgenogram in any of the patients. A 14% (average) narrowing of the vertebral foramina was evident in seven cases. In one patient, a fusion progressively developed 7 years after the acute episode (before full skeletal maturity). However, several patients appear to be progressing toward fusion of adjacent vertebra. A study of histologic specimens elucidated vascular anatomy of the immature vertebra that further explain the disease characteristics. PMID- 9364387 TI - The kinematic patterns of toe-walkers. AB - Children who toe-walk can pose a diagnostic problem. The differential diagnosis includes mild spastic diplegia and idiopathic toe-walking. Clinical differentiation between these two patient groups can be particularly difficult, and there are no objective diagnostic tests to assist the clinician. We assessed 50 children who toe-walk to define the kinematic patterns of lower-limb joint motion in the sagittal plane. There were 23 children with mild spastic diplegia. 22 idiopathic toe-walkers, and five normal children who were asked to toe-walk. We found characteristic patterns of knee and ankle motion that differentiated spastic diplegia from idiopathic toe-walking. Normal children asked to toe-walk had the same pattern as the idiopathic group. Gait analysis is a diagnostic tool that enables the clinician objectively to differentiate mild spastic diplegia from idiopathic toe-walking. PMID- 9364388 TI - Split tibialis posterior tendon transfer in the treatment of spastic equinovarus foot. AB - Sixteen patients with cerebral palsy causing equinovarus deformity were treated surgically. All of these patients underwent preoperative gait analysis by using a CODA-3 motion analyzer. The equinus deformity was assessed by using sagittal kinematics, and in particular, the range of movement of the ankle during stance phase and the maximal dorsiflexion during swing. The varus deformity was assessed by the degree of varus of the foot at prepositioning. The degree of varus was obtained by measuring the angle generated between the plane of progression and a line joining a marker on the heel to a marker on the fifth metatarsal in the transverse plane. All patients underwent split tibialis posterior tendon transfer and, in 13, this was combined with tendo calcaneus lengthening. Clinical assessment and gait analysis repeated 1 year postoperatively confirmed good outcome after split tibialis posterior tendon transfer in combination with gastrocnemius lengthening. This was confirmed by using sagittal kinematic analysis and quantitative assessment of the degree of varus of the foot at the time of prepositioning. PMID- 9364389 TI - Partial wound closure after surgical correction of equinovarus foot deformity. AB - Full correction of severe equinovarus foot deformities is frequently lost at the end of surgical release when the surgeon closes the skin incision. We retrospectively review 31 feet in 22 patients whose medial skin incisions were left open (typically 10 mm) to heal by secondary intention. The criterion to leave a wound open was if primary closure with the foot in full correction might compromise circulation to the skin or if closing the incision would require loss of corrected position. One or two cast changes were performed under outpatient anesthesia at 7- to 14-day intervals for wound care. All wounds except one were healed by week 6 at time of outpatient clinic cast removal. The appearance of the incisions is similar to feet in which primary closure is possible. One foot required split-thickness skin grafting at 3 weeks postoperatively to achieve wound coverage. There were no infections. We conclude that primary skin closure is not essential after surgical correction of equinovarus foot deformity, and that correction need not be compromised to approximate skin. PMID- 9364390 TI - Complete subtalar release in resistant clubfeet: a critical analysis of results in 146 cases. AB - A series of 101 patients (146 feet) with resistant clubfoot corrected by complete subtalar release is presented. A detailed rating system was used to evaluate the results. Minimum follow-up was 2 years. Fourteen feet (9.6%) had undergone additional surgical procedures at the time of review, and 101 feet (69%) had excellent or good functional ratings at that time. The mean total ankle motion was 34.2 degrees (range, 8-56 degrees). The better results occurred in feet without previous surgery. Final ankle range of motion was increased by using a special flexed-knee cast with reserve space above the foot. Longer follow-up is needed to determine the optimal age for surgery. PMID- 9364391 TI - Idiopathic forefoot-adduction deformity: medial capsulotomy and abductor hallucis lengthening for resistant and severe deformities. AB - Between February 1981 and March 1993, 18 children (29 feet) with resistant forefoot adduction underwent medial capsulotomy and abductor hallucis lengthening for correction. There were 12 feet with metatarsus adductus (two simple, 10 complex) and 17 feet with skewfoot (15 simple and two complex). The mean age at the time of operation was 3.6 years (range, 9 months-5.5 years). When seen 3.6 years (range, 1-8) after surgical correction, all of them showed an improved talofirst metatarsal angle. Two children complained of pain in the foot, and one child had persistent difficulty with shoe fitting. We conclude that medial capsulotomy and abductor hallucis lengthening is a simple procedure that is effective in improving metatarsus adductus deformity. PMID- 9364392 TI - Cleft-foot closure: a simplified technique and review of the literature. AB - The purpose of this article is to present a simplified technique to close the cleft in the feet of children affected with congenital clefts. This technique evolved after several frustrating attempts to close the cleft with mediocre results by using triangular flaps. This report concerns nine children with 15 feet. We describe a simplified technique for cleft closure to narrow the feet. One of the children had an associated syndactyly of the foot, and two others had syndactyly of the hands. No other associated anomalies were present in these children. We operated on seven patients with a total of 42 operations. The feet with the clefts that were repaired by rectangular flaps maintained good cosmesis and function. PMID- 9364393 TI - Anterior cruciate ligament tears in children: an analysis of operative versus nonoperative treatment. AB - A 12-year retrospective analysis of 42 children with arthroscopically confirmed anterior cruciate ligament disruption was undertaken to determine (a) the subjective efficacy of treatment, (b) the clinical and biomechanical results of operative and nonoperative management, and (c) the most appropriate long-term outcome measurements. Patients were followed up for a mean of 5.3 years from the time of initial treatment and were between the ages of 5 and 17 years (mean, 14.4) at the time of treatment. The children were treated nonoperatively by primary ligament repair or by intraarticular anterior cruciate ligament reconstruction. In the child, a complete tear of the anterior cruciate ligament was best managed by intraarticular surgical reconstruction. This was confirmed by clinical examination (p < 0.01), by a composite knee score involving a clinical examination and patient questionnaire (p < 0.0005), and by testing with the KT 1000 arthrometer. No significant differences in outcome could be attributed to the patient age or the maturity of the growth plates. In the active child, anterior cruciate reconstruction for complete tears resulted in a more stable and functional knee. PMID- 9364394 TI - Ultrasonography of the patellofemoral joint in diastrophic dysplasia. AB - Plain radiographs do not provide adequate information in diastrophic dysplasia (DD) because of abnormal ossification and severe deformation of the knee joint. Radiographically, the lateral femoral condyle is hypoplastic, and the position of patella is difficult to define. In clinical examination, the patella is inferior and lateral. In this study, the anatomy of the patellofemoral joint in DD is described using ultrasound. Both knees of 13 patients with DD were examined. The alignment of patella, the angle of femoral sulcus, and the size of both femoral condyles were measured. Student's paired t test with two-tailed significance probability was applied for differences in mean values, and their 95% confidence limits were computed. The femoral sulcus angle averaged 129 degrees and was deeper than that (142 degrees) in normal knees. The lateral femoral condyle was smaller than the medial condyle. The patella was aligned lateral to the bottom of femoral sulcus. In 10 degrees knee flexion, the patella remained laterally in the sulcus with no true patellar dislocation. Vertical position of the patella averaged 2.9 mm distal to the femorotibial joint. The study showed that, in patients with DD, the anatomic complex of the femoral condyles and patella deviates laterally, and the patellofemoral joint is deformed with a hypoplastic lateral condyle, a deep femoral groove, and a distally aligned patella. PMID- 9364395 TI - Treatment of patellofemoral instability in childhood with creation of a femoral sulcus. AB - Four patients with six knees with patellofemoral instability and severe trochlear dysplasia were treated with creation of a femoral sulcus. None of the six knees have had recurrent dislocations at 3- to 11-year follow-up. All patients had chromosomal abnormalities and limited motor demands. We recommend this procedure for children with patellar instability refractory to standard treatment methods who have severe trochlear dysplasia and limited motor demands. PMID- 9364396 TI - Radiological study of severe proximal femoral focal deficiency. AB - Twenty-two hips in 20 children, all classified as Amstutz type 3 proximal femoral focal deficiency, were studied by means of plain radiographs, arthrograms (30), ultrasound examination (six), computed tomography (CT) scans (including five arthrographies with CT) and magnetic resonance imaging (MRI; nine). These investigations demonstrated that in 15 hips, the superior femoral epiphysis was mobile in the acetabulum, whereas in six others, it was fixed and fused to the acetabulum. In one case, it was impossible to prove whether the epiphysis was mobile or fixed. The key radiologic and other image features that allow these conclusions to be drawn are described. The therapeutic implications are important, as it would be pointless or harmful to attempt to consolidate the femoral neck or put it into valgus when the epiphysis is spontaneously fixed to the acetabulum. PMID- 9364397 TI - Rotational deformity in congenital hypoplasia of the femur. AB - Congenital shortening of the femur is associated with significant limb-length discrepancy, distal femoral valgus with condylar hypoplasia, anteroposterior knee instability, and an external rotation deformity. This latter deformity has not been described or characterized in the literature. Eight patients with hypoplastic femora were evaluated clinically and radiographically including computed tomography (CT) anteversion studies. The average limb-length inequality at the time of examination was 7.8 cm. All affected extremities had significant retroversion averaging 17.4 degrees, representing a mean difference of 43.1 degrees from the contralateral normal anteversion of 25.7 degrees. Associated limb deformities included deficiency of the fibula in five patients and absent lateral foot rays in two patients. Five of the eight patients have undergone femoral lengthening with correction of angular, length, and rotational abnormalities through two-level osteotomy. The patient with femoral hypoplasia should have evaluation of length and angular abnormalities and rotational deformity as well. PMID- 9364398 TI - Focal fibrocartilaginous dysplasia in the upper extremity. AB - Focal fibrocartilaginous dysplasia is a benign lesion known to cause tibia vara in young children. To date, this lesion has been recognized in only the proximal medial tibia. This study reports two additional cases of focal fibrocartilaginous dysplasia occurring in the long bones of the upper extremity. The clinical presentation, radiographic appearance, histopathology, and natural history of focal fibrocartilaginous dysplasia in the humerus and ulna are analogous to published descriptions involving the tibia. Spontaneous resolution of the lesion and the resultant angular deformity is possible but not entirely predictable. Limb-length discrepancy should be anticipated. PMID- 9364399 TI - Recurrent posterior shoulder dislocation in children: the results of surgical management. AB - Recurrent posterior dislocation of the glenohumeral joint in children is rare. Because very few studies in the literature deal with the surgical management of this problem or guidelines for patient selection for surgery, we reviewed the outcomes of surgical management of six patients aged 9-17 years. Of the seven shoulders repaired, three underwent a posterior bone block and four a glenoplasty, all augmented with a posterior Putti-Platt type capsulorrhaphy. Only one child required reoperation 3.5 years after the initial surgery. All patients had pain-free full use of the affected shoulder, and all shoulders were clinically stable at long-term follow-up averaging 9.4 years. By using the available literature and the results of this study, we developed a series of guidelines for the selection of children with recurrent posterior dislocation of the shoulder for surgical repair. PMID- 9364400 TI - Measurement of molecular association in drug: cyclodextrin inclusion complexes with improved 1H NMR studies. AB - The molecular association of haloperidol with hydroxypropyl-beta-cyclodextrin, expressed by the binding constant of the inclusion complex formed, was calculated from the changes on the 1H NMR spectra of the drug in the presence of the cyclodextrin. The stoichiometry of the complex was calculated by use of the continuous variation method (Job plot), and found to be 1:1. The binding constant for the 1:1 complex was calculated using improved non-linear models, which were solved by non-linear least-squares regression analysis, applying an iteration procedure. Three improved mathematical models for more accurate calculation of binding constants are proposed. The models are free from any assumptions and from practical or theoretical shortcomings. PMID- 9364401 TI - Poly(alkyl cyanoacrylate) nanocapsules as a delivery system in the rat for octreotide, a long-acting somatostatin analogue. AB - Poly(alkyl cyanoacrylate) nanocapsules have been used as biodegradable polymeric drug carriers for subcutaneous and peroral delivery of octreotide, a long-acting somatostatin analogue; their ability to reduce insulin secretion or prolactin secretion in response to oestrogens has been studied in adult male rats. The nanocapsules, prepared by interfacial emulsion polymerization of isobutyl cyanoacrylate, were 260 nm in diameter and incorporated 60% of octreotide. Administered subcutaneously, the octreotide-loaded (20 micrograms kg-1) nanocapsules suppressed the insulinaemia peak induced by intravenous glucose overload and depressed insulin secretion over 48 h, preventing the secretory rebound; however, glycaemia was unaffected. In parallel, the plasma octreotide concentration increased 2.7 times. Administered perorally to oestrogen-treated rats, octreotide-loaded nanocapsules (200 and 1000 micrograms kg-1) significantly improved the reduction of prolactin secretion (by 72 and 88%, respectively, compared with 32 and 54% with free octreotide) and slightly increased plasma octreotide level. Thus nanocapsules could be of interest as a biodegradable drug carrier for the administration of octreotide. PMID- 9364402 TI - Effects of penetration enhancers on the in-vitro percutaneous absorption of progesterone. AB - Because progesterone seems suitable for treatment of premenstrual syndrome, the influence of penetration enhancers such as propylene glycol, urea and laurocapram (Azone) on the percutaneous absorption of progesterone from carbopol hydroalcoholic gels and from poly(ethylene glycol) ointments has been investigated. Skin experiments were performed using excized abdominal rat and porcine skin. Addition of 10% laurocapram was found to be the most efficient enhancer for progesterone from carbopol hydroalcoholic gels, for both rat and porcine skin; the next most efficient enhancer was urea in poly(ethylene glycol) bases. This enhanced the diffusion rates 2.5 fold, compared with pure poly(ethylene glycol) alone. The results show that hydroalcoholic gels and poly(ethylene glycol) ointments are both suitable vehicles for progesterone and that premenstrual syndrome might be treated effectively by use of hydroalcoholic gels containing 10% laurocapram. PMID- 9364403 TI - Nebulized interleukin 2 liposomes: aerosol characteristics and biodistribution. AB - Although interleukin 2 (IL-2) has been associated with modest anti-tumour responses in man, treatment-related toxicity has limited its widespread use. The local delivery of liposomal formulations of interleukin 2 to the lung as aerosols has been demonstrated to be non-toxic, biologically active, and associated with regression of spontaneous pulmonary metastases in dogs. This study was undertaken to evaluate the physical and biological characteristics of nebulized interleukin 2 liposomes. The aerosol droplet size distribution and the physical stability of interleukin 2 liposomes were examined in-vitro using an Andersen cascade impactor and studies of liposome entrapment of interleukin 2 before and after nebulization. The biological stability of interleukin 2 liposomes after nebulization was demonstrated using the CTLL-2 bioassay for interleukin 2. In vivo studies of pulmonary biodistribution and clearance of inhaled technetium (99mTc)-labelled interleukin 2 liposomes were undertaken in a normal dog. Aerosols of free interleukin 2 and of interleukin 2 liposomes were compared in both in-vitro and in-vivo experiments. The mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) of interleukin 2 liposomes were 1.98 microns and 2.02, respectively. Independent analysis of aerosol particle size distribution using the constitutive components of the interleukin 2 liposomes (interleukin 2: lipid:HSA) demonstrated a close correlation of size distributions (r = 0.9445; P < 0.001). The entrapment of interleukin 2 in liposomes was 93 +/- 4.3% before nebulization and 90 +/- 8.9% after. After delivery to an anaesthetized dog, interleukin 2 liposome aerosols were deposited evenly throughout the lung (mean +/- s.d. central lung-to-peripheral lung deposition was 1.12 +/- 0.03). After approximately 24 h inhalation, interleukin 2 liposomes were retained within the lung and were taken up in part by the spleen. The results of this study are indicative of the stability of this interleukin 2 liposome formulation to nebulization. Such nebulization might be an attractive immunotherapeutic strategy for treatment of pulmonary metastases and primary lung cancers. PMID- 9364404 TI - Enhanced anticancer therapy mediated by specialized liposomes. AB - It has been a central aim of experimental and clinical therapeutics to deliver therapeutic agents as close as possible to, or if possible within, a diseased cell. Such targeting achieves two major aims of drug delivery, the maximum dose of therapeutic agent to the diseased cell and avoidance of uptake by and, usually, accompanying side-effects to normal, healthy cells. Conventional liposomes, originally used for studies in membrane biophysics and biochemistry, have been used in therapy for the past two decades. However, when applied to deliver drugs into cells, conventional liposomes proved inefficient and so novel unconventional or specialized liposomes are constantly being prepared to enhance cell-specific delivery in-vivo. One possible way of achieving better targeting is combination of the positive attributes of more than one specialized type of liposome into one vesicle. Although a limited number of studies has examined the combined effect of such dual-specialty liposomes, more studies are warranted using appropriate models. Liposomes are composed of one, a few, or many concentric bilayer membranes which alternate with aqueous spaces. The drugs are encapsulated within the aqueous internal volume if they are hydrophilic or in the lipid bilayers if they are hydrophobic (Kim 1993). Liposomes range in size from 25 nm to more than 20 microns (Sugarman & Perez-Soler 1992). Depending on their solubility and method of formulation antimicrobial, cytotoxic and other conventional drugs, hormones, antigens, enzymes, genetic material, viruses and bacteria can be incorporated in either the aqueous or hydrophobic phase. This review discusses the types and characteristics of non-conventional liposomes used in various modes of cancer therapy, mainly chemotherapy and gene therapy. It concludes with suggestions on improving these novel liposomal to effect better targeting to cancer cells. PMID- 9364405 TI - Effect of application volume and area on the absorption of phenol red, as a model drug, from the liver surface in rats. AB - To determine the influence of the method of administration of a pharmaceutical formulation we have examined the importance of application volume and area in the absorption of phenol red, as a model drug, from the rat-liver surface. When 1 mg phenol red was applied to the rat-liver surface, in-vivo, in three volumes (0.1, 0.2 or 0.334 mL) using a cylindrical glass cell (i.d. 9 mm), the shape of the plasma concentration profile differed greatly, particularly the maximum concentration. These patterns were well fitted by a two-compartment model with first-order absorption, and the absorption-rate constant Ka obtained was inversely proportional to the application volume. The absorption ratio and biliary recovery of phenol red after 6 h increased with glass cell area (i.d. 6, 9 or 14 mm; area 0.28, 0.64 or 1.54 cm2). Furthermore, the permeability coefficient Papp derived from Ka did not depend on application area, indicating no difference in the absorption characteristics of the liver surface. This also implies transport of the drug by passive diffusion from the liver surface. After intraperitoneal administration to the rat-liver surface for clinical application, increasing the application volume resulted in the delayed disappearance of phenol red from the plasma. However, the difference was not as marked as that obtained by use of the glass cell. The assumption that the effective area relating to the absorption changed with the application volume enabled us to estimate Papp. Consequently, we speculate that absorbability can be estimated precisely by consideration of application volume and area. PMID- 9364406 TI - Regional differences in calcium sensitivity in the guinea-pig intestine. AB - The effect of the Ca(2+)-channel antagonist nicardipine on the basal tone of six segments (duodenum, jejunum, ileum, proximal colon, distal colon and rectum) of the guinea-pig intestine has been investigated in muscle preparations. Nicardipine reduced the basal tone of the proximal and distal colon but not of the duodenum, jejunum, ileum and rectum. Similarly, when each segment was incubated in Ca(2+)-free medium, the basal tone of the proximal and distal colon, but not that of the other four segments, was reduced. The reduced basal tone recovered after cumulative addition of Ca2+ in both colon preparations. The basal tone of the distal colon was partly reduced by tetrodotoxin, atropine and clonidine. Conversely, L-type Ca(2+)-channel antagonists (Cd2+, verapamil and nicardipine), but not the T-type Ca(2+)-channel antagonist Ni2+, completely reduced the basal tone of the distal colon. These results indicate that in the regulation of basal tone there are additional regional differences in the effect of Ca2+ influx into the cells from the extracellular fluid which might involve L type-like Ca2+ channels and might partly be because of neuronal factors. PMID- 9364407 TI - Inhibition of potassium (KATP) channels reduces the short-circuit current response of rat colonic mucosa to acetylcholine. AB - Intestinal secretion depends upon electrogenic chloride transport into the gut lumen, which requires maintenance of an electrically negative cell-membrane voltage. We have investigated whether secretory responses of rat colonic mucosa to acetylcholine were sensitive to inhibition of potassium channels and whether selective inhibition could indicate the nature of the channel involved. Rat colonic mucosa was set up in Ussing chambers, short-circuit current responses obtained to acetylcholine, and the sensitivity of such responses to inhibition of potassium channels was investigated. Non-selective potassium-channel blockade by barium induced concentration-dependent inhibition of responses to acetylcholine. Similar inhibitory effects were obtained using 4-aminopyridine and glibenclamide. 5-Hydroxydecanoate and phentolamine also inhibited the increase in short-circuit current. However, a combination of charybdotoxin plus apamin was without effect. We conclude that a basolateral outward movement of potassium ions is required for the secretory action of acetylcholine on rat colonic mucosa. The potassium channel involved seems to be ATP-dependent and calcium-insensitive. PMID- 9364408 TI - Nitric oxide modulates the acute increase of gastrointestinal transit induced by endotoxin in rats: a possible role for tachykinins. AB - Because of the evidence that endogenous nitric oxide (NO) plays an essential role in the physiological regulation of gastrointestinal motility we have investigated, by use of the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), the role of endogenous NO in the acute endotoxin-induced changes of gastrointestinal transit. Pre-treatment with E. coli endotoxin (100 micrograms kg-1, i.v.) induced a significant increase in the gastrointestinal transit of a charcoal suspension in anaesthetized rats. Previous administration of the NO synthase inhibitor, L-NAME (10 mg kg-1, i.v.) significantly prevented the effects of endotoxin. L-arginine (200 mg kg-1, i.v.) and the substance P antagonist [D Pro2, D-Trp7,9]-substance P (SPA), significantly reversed the effects of L-NAME on gastrointestinal transit in rats treated with endotoxin. Pre-treatment with dexamethasone (5 mg kg-1, s.c., twice), an inhibitor of the expression of inducible NO synthase, did not affect the increase in the gastrointestinal transit through constitutive NO synthesis. The results suggest that constitutive nitric oxide is involved in the increase of gastrointestinal transit induced by endotoxin and that the reduction in transit induced by L-NAME in endotoxin treated rats is mediated by endogenous tachykinins. PMID- 9364409 TI - Effects of meloxicam, compared with other NSAIDs, on cartilage proteoglycan metabolism, synovial prostaglandin E2, and production of interleukins 1, 6 and 8, in human and porcine explants in organ culture. AB - Some non-steroidal anti-inflammatory drugs (NSAIDs) can accelerate joint damage in osteoarthritis by enhancing the production of pro-inflammatory cytokines or inhibiting cartilage proteoglycan synthesis. Meloxicam, a new NSAID, was compared with standard NSAIDs for its effect on proteoglycan synthesis and degradation in human and porcine cartilage explants, as well as the production of prostaglandin E2 (PGE2) and interleukins 1 and 6 by human synovial tissue explants in-vitro. Meloxicam at submicromolar concentrations inhibited synovial PGE2 production but, up to therapeutic drug concentrations (< or = 4 microM), did not affect synovial production of the pro-inflammatory cytokine IL-1. In contrast, hydrocortisone, 10 microM, a positive control, inhibited release of this cytokine, and indomethacin, 100 microM, increased its production. The lack of effects of meloxicam were evident irrespective of intrinsic IL-1 bioactivity of the synovia, production of IL-1 inhibitors or time of incubation. Production of the part anti-inflammatory cytokine IL-6, was significantly increased by therapeutic concentrations of meloxicam, as well as by indomethacin. Another major pro-inflammatory cytokine, IL-8, was unaffected by therapeutic concentrations of meloxicam. Meloxicam, 0.1 4.0 microM, did not affect cartilage proteoglycan production whereas indomethacin, 100 microM, significantly reduced synthesis of these macromolecules. Thus meloxicam, at concentrations within the therapeutic range and at which pronounced inhibition of prostaglandin production is evident, affects neither cartilage proteoglycan production nor the production of those cytokines likely to be important in cartilage destruction. PMID- 9364410 TI - Effect of policosanol on circulating endothelial cells in experimental models in Sprague-Dawley rats and in rabbits. AB - The effect of policosanol on circulating endothelial cells has been studied in different experimental models with endothelium damage. Oral administration of 25 mg kg-1 policosanol to Sprague-Dawley rats resulted in significant protection of the endothelial lining against the desquamating effect of citrate. Oral administration of 5 mg kg-1 policosanol to spontaneously hypertensive rats (SHR) resulted in a significant reduction of circulating endothelial cells compared with controls. Moreover, comparison between groups revealed a lower frequency of aortic lesions in policosanol-treated animals than in controls. On the other hand, administration of 5 mg kg-1 policosanol to rabbits with intimal hyperplasia induced by cuff placement in the carotid artery resulted in levels of circulating endothelial cells significantly lower than in controls. These results demonstrate the protective effect of policosanol in different experimental models and suggest its potential for endothelial protection. PMID- 9364411 TI - The effect on plasma glucose, insulin and glucagon levels of treatment of diabetic rats with the medicinal plant Rhazya stricta and with glibenclamide, alone and in combination. AB - Because many diabetic patients in the United Arab Emirates use medicinal plants as a supplement to treatment with insulin or oral hypoglycaemic agents, the effect on plasma glucose, insulin and glucagon concentrations of simultaneous treatment of streptozotocin-diabetic rats with Rhazya stricta extract and glibenclamide has been examined. Treatment of control rats with the extract at oral doses of 0.5, 2.0 and 4.0 g kg-1 did not significantly affect the concentration of glucose, insulin or glucagon for up to 4 h after administration of the extract. The same doses in diabetic rats reduced the glucose level 1 h (2 and 4 g kg-1) and 2 h (4 g kg-1) after administration of the extract. This was accompanied by significant increases in insulin concentration 1, 2 and 4h after administration of the extract at doses of 2 and 4 g kg-1. Glibenclamide (2.5, 5.0 and 10.0 mg kg-1) dose-dependently reduced glucose and glucagon levels, and increased that of insulin in normal and diabetic rats. Simultaneous treatment of normal and diabetic rats with the plant extract (0.5, 2.0 and 5.0 g kg-1) and glibenclamide (5.0 mg kg-1) significantly exacerbated the effects on glucose, insulin and glucagon induced by the extract or by glibenclamide when given separately. When the plant extract was given at doses of 0.5, 2 and 4 g kg-1 per day for 6 consecutive days the glucose level was reduced by approximately 6, 8 and 30%, respectively. No significant effect was seen on the levels of cholesterol or protein. These results imply that co-administration of the extract with glibenclamide might adversely interfere with glycaemic control in diabetic patients. PMID- 9364412 TI - Impulse-response studies on tracer doses of [14C]lignocaine and its multiple metabolites in the perfused rat liver. AB - The outflow-concentration-time profiles for lignocaine (lidocaine) and its metabolites have been measured after bolus impulse administration of [14C]lignocaine into the perfused rat liver. Livers from female Sprague-Dawley rats were perfused in a once-through fashion with red-blood-cell-free Krebs Henseleit buffer containing 0 or 2% bovine serum albumin. Perfusate flow rates of 20 and 30 mL min-1 were used and both normal and retrograde flow directions were employed. Significant amounts of metabolite were detected in the effluent perfusate soon after lignocaine injection. The early appearance of metabolite contributed to bimodal outflow profiles observed for total 14C radioactivity. The lignocaine outflow profiles were well characterized by the two-compartment dispersion model, with efflux rate << influx rate. The profiles for lignocaine metabolites were also characterized in terms of a simplified two-compartment dispersion model. Lignocaine was found to be extensively metabolized under the experimental conditions with the hepatic availability ranging between 0.09 and 0.18. Generally lignocaine and metabolite availability showed no significant change with alterations in perfusate flow rate from 20 to 30 mL min-1 or protein content from 0 to 2%. A significant increase in lignocaine availability occurred when 1200 microM unlabelled lignocaine was added to the perfusate. Solute mean transit times generally decreased with increasing flow rate and with increasing perfusate protein content. The results confirm that lignocaine pharmacokinetics in the liver closely follow the predictions of the wellstirred model. The increase in lignocaine availability when 1200 microM unlabelled lignocaine was added to the perfusate is consistent with saturation of the hydroxylation metabolic pathways of lignocaine metabolism. PMID- 9364413 TI - Effects of two N-arylpiperazinylmethylpyrazolo [1,5-d][1,2,4]triazine derivatives in pain and antidepressant tests in mice. AB - The antinociceptive and antidepressant effects of two pyrazolotriazine derivatives, 2-phenyl-3,3a-dihydro-4-oxo-5-(4-phenylpiperazin-1-yl) methyl pyrazolo[1,5-d][1,2,4]-triazine (SM1) and 2-phenyl-3,3a-dihydro-4-oxo-5-[4-(4 fluorophenyl)piperazin-1-yl] methylpyrazolo[1,5-d][1,2,4] triazine (SM3) have been investigated in mice using classical pharmacological tests. The intraperitoneal LD50 values of SM1 and SM3 were 253.4 and 218.8 mg kg-1 respectively. SM1 and SM3 showed analgesic properties in the phenylbenzoquinone induced abdominal constriction test (ED50 approximately 10-15 mg kg-1, i.p.) and in the hot-plate test. The antinociceptive effects of the triazines were significantly reduced by administration of naloxone (1 and 3.2 mg kg-1, s.c.) and yohimbine (1 mg kg-1, p.o.). Acute intraperitoneal administration of both compounds (1 mg kg-1 SM1 or 1.5 mg kg-1 SM3) potentiated morphine (0.15 mg kg-1, s.c.) analgesia in the phenylbenzoquinone test. Although this synergistic activity was not reversed by methysergide (0.5 mg kg-1, i.p.), the analgesic activity of both compounds was enhanced by administration of 5-hydroxytryptophan (50 mg kg-1, i.p.) in conjunction with carbidopa (25 mg kg-1, i.p.). Furthermore, neither compound (at 100 mg kg-1, i.p.) significantly reduced the duration of immobility of mice in the forced swimming test, and both (at 75 mg kg-1, i.p.) were ineffective at enhancing the toxic effects of yohimbine (30 mg kg-1, s.c.). Only SM3 (ED50 = 74.5 mg kg-1, i.p.) significantly antagonized reserpine (2.5 mg kg-1, i.p.)-induced ptosis. Thus, the results suggest that SM1 and SM3 have antinociceptive properties related to co-involvement of opioidergic and alpha 2 adrenoceptor mechanism without associated antidepressant properties. PMID- 9364414 TI - Interaction between pefloxacin and aminophylline in genetically epilepsy-prone rats. AB - The effects of a chronic treatment with pefloxacin on aminophylline-induced seizures in genetically epilepsy-prone rat have been investigated. Two series of experiments were performed. In the first, animals received pefloxacin orally twice a day for five days, then were administered aminophylline intraperitoneally and the occurrence of seizures was evaluated. In the second series of experiments, theophylline serum concentration was evaluated in rats subject to the same experimental protocol. Pefloxacin significantly, and in a dose-dependent manner, increased the occurrence of seizure phases induced by aminophylline, but did not influence theophylline serum levels measured at different times after the injection of aminophylline. We suggest that additive neurotoxic effects of both pefloxacin and aminophylline might contribute to the increased severity of seizure score. The possible role of GABA-benzodiazepine, excitatory amino acid and purinergic mechanism, and the role of pharmacokinetic factors are discussed. PMID- 9364415 TI - Beneficial effects of clonidine in streptozotocin-induced diabetes and DOCA hypertensive rats. AB - This investigation was undertaken to study the effects of chronic treatment with clonidine on cardiovascular complications in streptozotocin-induced diabetes and DOCA-hypertensive rats. Injection of streptozotocin induced glucosuria, hyperglycaemia, hypoinsulinaemia, hypothyroidism, hypercholesterolaemia, hypertriglyceridaemia, bradycardia and a decrease in left ventricular developed pressure (LVDP). DOCA by itself did not induce any change in blood-glucose levels in non-diabetic animals. However, in diabetic animals DOCA significantly reduced blood-glucose levels. Treatment of diabetic and diabetic hypertensive animals with clonidine (25 micrograms kg-1 every day for six weeks) significantly prevented diabetes-induced loss of body weight, bradycardia, cardiac hypertrophy and hypothyroidism. It also partially, but significantly, prevented diabetes induced hyperglycaemia and hypoinsulinaemia in both diabetic and diabetic hypertensive animals. There was a significant reduction in diabetes-induced elevation of cholesterol and triglyceride levels and an improvement in LVDP at higher filling pressure in diabetic and diabetic hypertensive animals. This investigation shows that chronic treatment with clonidine produces a number of beneficial effects such as prevention of hyperlipidaemia and hypothyroidism and improvement in cardiomyopathy and glycaemic control in diabetic and diabetic hypertensive rats. PMID- 9364416 TI - Synthesis of several substituted phenylpiperazines behaving as mixed D2/5HT1A ligands. AB - Twenty-two different compounds have been synthesized with the aim of creating new, mixed D2/5HT1A ligands. For this purpose 1-substituted phenylpiperazines attached by the N-4 nitrogen to dopaminergic pharmacophores of the 2-(5 benzimidazole)ethyl-, 2-(5-benztriazole)ethyl-, 2-[5-(benzimidazole-2 thione)]ethyl- and 2-[6-(1,4-dihydroquinoxaline-2,3-dione)]ethyl-type were selected according to known structure-affinity requirements of 1-arylpiperazines. All the new compounds were evaluated for in-vitro binding affinity at the dopamine (D1 and D2) and 5-HT1A receptors. Synaptosomal membranes prepared from fresh bovine caudate nuclei and hippocampi were used as a source of dopamine and 5-hydroxytryptamine receptors, respectively. [3H]SCH 23390 (D1 selective), [3H]spiperone (D2 selective) and 8-OH-[3H]DPAT (5-HT1A selective) were employed as the radio-ligands. None of the compounds expressed affinity for binding at D1 dopamine receptors. Compounds 3b and 4b were inactive 8-OH-[3H]DPAT competitors whereas 1b, 2b and 4b were inactive in the [3H]spiperone-binding assay. The other compounds tested showed fair (1c, 1e, 1f, 2c, 2f, 3b, 3c and 4c) to high (1a, 1d, 2a, 1d, 3a, 3d-3f, 4a, and 4d) affinity in the [3H]spiperone-binding assay, the most potent representative being 4-[2-(5-benzimidazole-2-thione)ethyl]-1-(2 methoxyphenyl)piperazine, 3a (Ki = 1.7 nM). In the 8-OH-[3H]DPAT-displacement assay compounds 1b, 1d, 1f, 2b, 2f and 3f behaved as moderate competitors and 1a, 1c, 1e, 2a, 2c, 2d, 3a, 3c-3e, 4a, 4c, 4d and 4f as rather strong competitors; 4 [2-(5-benztriazole)ethyl]-1-(2-methoxyphenyl)piperazine, 2a had the highest binding affinity at the 5-HT1A receptors (Ki = 2.6 nM). Because many antipsychotic and anxiolytic agents behave as mixed dopaminergic and serotonergic ligands, the high affinity of several of these new ligands for binding at both D2 and 5-HT1A receptors make them promising candidates deserving further pharmacological evaluation as antipsychotic or anxiolytic pharmaceuticals. PMID- 9364417 TI - A xanthanolide with potent antibacterial activity against methicillin-resistant Staphylococcus aureus. AB - This study was conducted to find constituents of an annual herb, Xanthium sibiricum Patr er Widd, with effective antibacterial activity against methicillin resistant Staphylococcus aureus (MRSA). By monitoring antibacterial activity against MRSA strains, it was shown that a sesquiterpene lactone, identified as [3aR-(3a alpha, 7 beta,8a beta)]-3,3a,4,7,8,8a-hexahydro-7- methyl-3-methylene-6 (3-oxo-1-butenyl)-2H-cyclohepta[b]furan-2-one, or xanthatin, isolated from leaves of the herb, had outstandingly potent activity against S. aureus species, including MRSA; its activity against MRSA and MSSA strains was similar. Other bacteria, e.g. Staphylococcus epidermidis, Klebsiella pneumoniae, Bacillus cereus, Pseudomonas aeruginosa and Salmonella typhi, were also susceptible at the concentrations tested but the compound had no inhibitory effect on some other bacteria, including Escherichia coli. The results show that xanthatin has outstandingly potent activity against strains of S. aureus but that the activity of the compound is highly species-specific. PMID- 9364418 TI - Assessment of the antitussive efficacy of codeine in cough associated with common cold. AB - Codeine is generally accepted as the standard antitussive against which new antitussive medications are compared. This presents a problem because the support for codeine's antitussive activity comes from studies on cough in animals, and chronic and induced cough models in man, whereas antitussives are almost exclusively used for the treatment of cough associated with acute upper respiratory tract infection (URTI). The aims of this study were twofold. Firstly, to study the antitussive efficacy of codeine in cough associated with URTI and, secondly, to validate a sound meter as tool for quantifying cough. The efficacy of codeine was assessed in a double-blind, stratified, placebo-controlled, parallel-group, clinical trial using three different measures of cough: cough sound-pressure levels (CSPLs) measured on a sound meter; subjective scores of cough severity; and cough frequency recorded by means of a microphone connected to an ink-pen recorder. A group of 82 subjects (51 females and 31 males; mean age 23.5 years, range 18-46 years) with cough owing to acute URTI were included in the study. The study took place on two separate study days. On study day 1 cough measurements were made before and 90 min after treatment with a single dose of either 50 mg codeine or matched placebo in capsule form. The same three measures of cough were repeated 2-5 days later (study day 2). On study day 1 a highly significant (P < 0.0001) decrease in all three measures of cough was found after treatment with both placebo and codeine yet there was no significant difference between the treatment groups. A highly significant (P < 0.0001) decrease in the three measures of cough was also found between days 1 and 2. The results demonstrate that codeine is no more effective than placebo in reducing cough associated with acute URTI, as measured by CSPLs, cough frequency or subjective symptom scores. This result might be explained on the basis of two central pathways for cough; a reflex pathway via the brain-stem which is sensitive to codeine and a voluntary pathway via the cortex which is unaffected by codeine. The results also demonstrate that the sound-level meter appears to be a potentially useful investigative tool for the assessment of cough and antitussive efficacy. PMID- 9364419 TI - Detection of cerebral microembolic signals by transcranial Doppler may be a useful part of the equation in determining stroke risk in patients with antiphospholipid antibody syndrome. PMID- 9364420 TI - Why women? PMID- 9364421 TI - A young woman with SLE: diagnostic and therapeutic challenges. AB - The presence of antiphospholipid antibodies, especially of the IgG isotype and in high titre, is associated with additional complications in patients with SLE. The thrombocytopaenia and cerebral events in the patient described are likely to have been linked to her lupus anticoagulant. However, the antibody and anticardiolipin antibodies are not necessarily synonymous and indeed we did not detect anticardiolipin antibodies in the patient, although her sister had them. It is likely that they represent overlapping sets of immunoglobulins. The production and analysis of further such antibodies, as described in this review, is awaited urgently. Much effort is also being expanded on identifying the precise targets for these antibodies. In a very recent report Horkko et al have shown that these antibodies may be directed against epitopes of oxidized phospholipids. The management of patients with complex disorders such as described here remain a challenge, although in the short term the patient's major locomotor, neurological, dermatological and haematological problems have been controlled. Long-term problems including impaired fertility and osteoporosis remain to be faced. PMID- 9364422 TI - Cerebral microemboli in patients with antiphospholipid syndrome. AB - CNS involvement is one of the hallmarks underlying poor prognosis in SLE and for therapeutic strategies it is difficult to assess which patients are at risk. As detectability of cerebral microembolic signals (MES) using long-term transcranial Doppler ultrasonography (TCD) proved to be predictive of past and future thromboembolic events in patients with carotid artery stenosis, we investigated whether MES might be similarly useful in patients with antiphospholipid syndrome (APS). Our study population consisted of 46 SLE patients and five with primary APS (pAPS). Twelve of the 46 patients with SLE, 10 of them with secondary APS (sAPS), and four of five patients with pAPS had a history of cerebrovascular ischaemia (CVI). MES in the middle cerebral artery were detected in 14 of 16 patients with and in one of 35 without CVI (P < 0.001). Antiphospholipid antibodies (aPL) were positive in 12 of 15 patients with and 18 of 36 without MES, and the rate of MES correlated to the titre of aPL. MES from APS patients resembled in their energy distribution those from patients with symptomatic carotid disease and were significantly different from those associated with artificial heart valves. In conclusion, cerebral MES are detectable in APS patients and correlate with a history of CVI. Whether this innovative method may provide individual risk assessment in APS patients has to be addressed in prospective studies. PMID- 9364423 TI - Anti-intercellular adhesion molecule-1 (ICAM-1) antibody treatment prevents central and peripheral nervous system disease in autoimmune-prone mice. AB - Abnormal neurological functioning similar to that seen in systemic lupus erythematosus (SLE) patients is detectable in an SLE-prone murine strain (MRL/lpr) by 8-10 weeks and is severe by 18 weeks of age. The purpose of this study was to evaluate the effectiveness of murine antiintercellular adhesion molecule-1 (ICAM-1) in suppressing neurological disease in MRL/lpr mice. Beginning at 6 weeks of age, five MRL/lpr mice received 5 weekly intraperitoneal injections of anti-ICAM-1-containing culture supernatant in phosphate-buffered saline (PBS) whereas four animals were treated with non-anti-ICAM-1 containing supernatant in PBS. A decline in neurological functioning began in control mice by 10 weeks, but anti-ICAM-1 treated mice remained normal throughout the study. All control mice had vasculitic skin lesions by 14 weeks of age whereas none of the anti-ICAM-1 treated mice ever developed skin lesions. Nerve conduction studies performed on all mice prior to sacrifice showed sciatic compound motor action potentials of anti-ICAM-1 treated mice that were of higher amplitude and shorter latency than those of controls. Inflammation in the sciatic nerve was more common in control mice. Brain histology revealed a similar degree of choroid plexus inflammation in both groups. Our study demonstrated that anti-ICAM-1 was effective in suppressing neurological abnormalities in MRL/lpr mice and may potentially be useful therapy in human SLE. PMID- 9364424 TI - Elevated anticardiolipin antibodies in autoimmune haemolytic anaemia irrespective of underlying systemic lupus erythematosus. AB - In patients with systemic lupus erythematosus (SLE) and concomitant Coombs positive autoimmune haemolytic anaemia (AIHA) anticardiolipin antibodies (aCL) are found more frequently and at higher titres than in SLE patients without AIHA. In order to assess if aCL elevation is primarily associated with the underlying SLE, or with AIHA itself, we examined AIHA patients with and without underlying SLE for the presence of aCL. aCL (IgG and IgM) were determined by ELISA in 74 SLE patients without AIHA, 22 SLE patients with AIHA, 50 patients with idiopathic AIHA (warm-reactive autoantibodies), 52 patients with idiopathic AIHA (cold reactive autoantibodies) and 50 healthy controls. The mean IgG and IgM aCL titres in SLE patients without AIHA (IgG 37.0 U/ml, IgM 8.9 U/ml) were significantly elevated compared with the values in healthy controls (IgG 9.1 U/ml, IgM 3.2 U/ml; P < 0.005). The mean aCL levels in SLE patients with AIHA (IgG 53.2 U/ml, IgM 28.2 U/ml) were higher than in SLE patients without AIHA (P = 0.09 for IgG, P < 0.005 for IgM). Interestingly, the mean aCL levels of patients with idiopathic AIHA (warm-reactive autoantibody type: IgG 29.2 U/ml, IgM 19.3 U/ml; cold reactive autoantibody type: IgG 27.4 U/ml, IgM 18.9 U/ml) were also significantly elevated compared with healthy controls P < 0.001). As aCL are elevated not only in SLE (with and without concomitant AIHA) but also in idiopathic AIHA it can be speculated that aCL are involved in the pathomechanism of autoantibody-induced erythrocyte destruction per se irrespective of an underlying SLE. PMID- 9364425 TI - Immunogenic properties of synthetic fragments of Sm-D protein in normal and lupus mice. AB - Antibodies against the Sm antigen are characteristic of systemic lupus erythematosus (SLE). They are found in 20-30% of SLE patients and it has been shown previously that up to 70% of SLE sera react with synthetic fragments 1-20 and 44-67 of the Sm-D polypeptide. To determine whether injections of these peptides might be pathogenic both were administered intraperitoneally into normal mouse strains BALB/c (H-2d), B10/brown (H-2k) and C57BL/6 (H-2b) and an autoimmune strain MRL/lpr (H-2k). IgG antibodies against peptide 1-20 were detected by ELISA in the sera of BALB/c and MRL/lpr mice but not in the sera of B10/brown and C57BL/6 mice. IgG antibodies against peptide 44-67 were found in the sera of BALB/c, B10/brown and MRL/lpr mice but not in the sera of C57BL/6 mice. Neither fragment induced a response against the whole Sm-D antigen as detected by Western blotting. Reactivity to synthetic fragments from other nuclear antigens was however detected in the sera of MRL/lpr mice, especially in those mice injected with Sm-D peptide 44-67 emulsified in Freund's adjuvant. Following immunization with Sm-D peptides, antibodies to ssDNA or dsDNA were not detected in the sera of BALB/c, B10/brown and C57BL/6 mice and in the MRL/lpr mice the naturally occurring production of these antibodies was not enhanced. No difference in IgG deposition in the renal glomeruli of the mice injected with the peptides compared with the control groups was observed. These results suggest that the humoral response to the Sm-D fragment is, at least partially, controlled by the MHC haplotype of the recipient mice, is related to dose and type of immunogen, and is also influenced by the presence of Freund's adjuvant. It is evident that although the sera of many SLE patients recognize either or both the 1-20 and 44-67 peptides, these peptides when injected into MRL/lpr mice are not directly pathogenic. PMID- 9364426 TI - Serological characteristics of systemic lupus erythematosus from a hospital-based rheumatology clinic in Kuwait. AB - Thirty-one consecutive patients with SLE were screened for antinuclear antibody (ANA), anti-DNA antibodies, extractable nuclear antigen antibodies (anti-ENAs) including anti-Sm, anti-RNP, anti-SSA (anti-Ro), anti-SSB; (anti-La), anti-Scl 70, rheumatoid factor (RF), C-reactive protein (CRP), C3 and C4 levels, anti cardiolipin antibodies (aCL), biologically false positive serological test for syphilis (BF-STS) using VDRL test and Coombs' test. The age of the patients ranged from 11 to 52 year with a median of 29 year; female to male ratio of 5:1. There were 21 Kuwaitis, four Egyptians, three from the Indian subcontinent, two Filipinos and one Syrian. Main clinical categories of SLE were: mild cutaneous SLE in 12 (38.7%), clinical antiphospholipid syndrome (APS) secondary to SLE in 8 (25.8%), haematological manifestations of SLE in 5 (16.1%), renal lupus in four (12.9%), neuropsychiatric in three (9.7%), others (6.4%). Clinical features overlapped in several patients. ANA was positive in 96.8% (mean value 891.61 units/ml), anti-DNA in 35.5% (mean value 56.4 units) that was lower than expected and could be due to selection bias as the patients were from a rheumatology clinic, anti-ENA in 42%, anti-Sm 13% that was lower than other non-Caucasian populations, anti-RNP 13%, anti-SS-A in 35.5%, anti-SS-B in 19.4%, Scl-70 in 13%, CRP in 71% (moderate 58%, very high 13%); C3 mean 1.52 mg/ml (3.2% low levels), C4 mean 0.35 mg/ml (32% low levels), anticardiolipin mean GPL 35.35 units (high 58%), mean MPL 10.61 units (high 26%), BF-STS in 6%, Coombs' test in 6%, RF positive in 36%. The only significant positive clinical associations observed were those of renal involvement with anti-DNA antibodies (P = 0.042), and clinical antiphospholipid antibody syndrome with aCL antibodies (P = < 0.05). PMID- 9364427 TI - Subclinical multisystemic autoimmunity presenting as a progressive myelopathy. AB - Autoimmunity can manifest clinically in many ways; however, despite the various efforts to classify autoimmune disorders into specific disease entities, the borders between these disorders remain, in many cases, unclear. In this report we describe a young woman with subclinical Sjogren's syndrome and biliary cirrhosis, who presents clinically with symptoms exclusively from the central nervous system. This neurological syndrome is consistent with a progressive myelopathy. Although the patient has a serologically and histologically confirmed multisystemic autoimmune disorder, she fulfills none of the classification criteria for the diagnosis of a specific connective tissue disease. PMID- 9364428 TI - Prevalence of antibodies to lipid A, lipopolysaccharide and lipoteichoic acid in systemic lupus erythematosus patients with antiphospholipid antibodies. PMID- 9364429 TI - Implementation of a patient-centred and physician-oriented healthcare information system. AB - Integration of information has enabled expeditious operation in air transfer, banking, shopping, and stock brokerage, but not in healthcare. Existing health information systems (HIS) are concerned too much with departmental performance and charge billing, and neglect the end users--the patients and the physicians. The resultant HIS then has divergent operation to antagonize the physicians, and has fragmented data to the disadvantage of patients. Recognizing the problems and the trend of HIS, this study proposed and implemented a patient-centred and physician-oriented HIS in a Urology clinic. The proposed HIS had patient care as its core, and accurately coded the patient's diagnoses and therapy information. It also offered a friendly environment and complete function for the physician to administrate medical records and to provide healthcare services. The HIS had client/server structure and an open system to protect the hardware investment and the software implementation. It will be the key to success in complete hospital environments. PMID- 9364430 TI - Computer assisted process management for health care: the IBIS tool. AB - IBIS is a broad range informatics tool, which can provide essential assistance to users during quality development projects in the health care environment. It can be used to set up a preliminary process model and specify variable and their interrelationships; the system propagates various quality related effects through the process structure, in a bottom up fashion, by linking quality indices to outcomes, repetitively, until arriving at the final outcome, at the top. An incorporated interactive browser is used to simulate the running process, to test and evaluate it, though a cause--effect interaction on intermediate or final outcomes. The tool provides guided support throughout the quality development procedure and during the continuous improvement process. At the same time, it constitutes an effective training tool on the principles of quality work. Additionally, IBIS can be used for the quality system's documentation, by means of a multimedia presentation, incorporating descriptive text, images and graphical displays, video sequences and sound. PMID- 9364431 TI - Integrating information systems in medicine: a reference model for middleware. AB - This paper addresses the problem of integrating healthcare information systems, from a technological viewpoint. We propose to take the concept of an ?integration service' as an elementary concept in discussing the problem of integration. We then propose a taxonomy for grouping integration services according to their functionality and their domain specificity. The use of this taxonomy for decomposing an integration problem into (less complex) sub-problems is demonstrated. Finally, a sequence of steps to be taken in solving an integration problem is discussed. PMID- 9364432 TI - Multiparametric time course prognoses by means of case-based reasoning and abstractions of data and time. AB - In this paper we describe an approach to utilize Case-Based Reasoning methods for trend prognoses for medical problems. Since using conventional methods for reasoning over time does not fit for course predictions without medical knowledge of typical course pattern, we have developed abstraction methods suitable for integration into our Case-Based Reasoning system ICONS. These methods combine medical experience with prognoses of multiparametric courses. We have chosen the monitoring of the kidney function in an Intensive Care Unit (ICU) setting as an example for diagnostic problems. On the ICU, the monitoring system NIMON provides a daily report based on current measured and calculated kidney function parameters. We abstract these parameters to a daily kidney function state. Subsequently, we use these states to generate course-characteristic trend descriptions of the renal function over the course of time. Using Case-Based Reasoning retrieval methods, we search in the case base for courses similar to the current trend descriptions. Finally, we present the current course together with similar courses as comparisons and as possible prognoses to the user. PMID- 9364433 TI - Clinical problem solving--the role of expert laboratory systems. AB - The objective was to determine whether or not a laboratory based computer diagnostic program could aid the clinician in solving problems, outside his or her field of expertise, by expertly interpreting ?Emergency Room' haematological and biochemical data and providing a list of possible diagnoses. The program, which uses Fuzzy Sets and pattern recognition as its Inference Mechanism coupled with a data base comprised of haematological and biochemical responses to disease collected over a period of 10 years in a teaching hospital, analysed data published in two leading journals--the 'Clinical Problem-Solving' section of the New England Journal of Medicine and the 'Lesson of the Week' feature of the British Medical Journal. It was found that the computer program often presented diagnoses not thought of by the clinician. With such a system, sometimes as few as three routine investigations suggested the diagnosis. The diagnostic accuracy could be improved with a more structured approach to ?Emergency Room' laboratory investigations. It is concluded that the computer, programmed to recognize a disease by the pattern of its response to routine haematological and biochemical investigations, could contribute significantly to diagnosis. PMID- 9364434 TI - An Expert PArasite IdentificatiON (EPAION) system with multimedia support. AB - Until now computer-assisted parasite identification was based on database applications requiring data specification on an individual basis, thus limiting the ability of the system to handle rule-based knowledge as humans are used to do. A new Expert PArasite IdentificatiON (EPAION: Greek term for expert) system was developed to serve as an interface between the database and the user, where the database is a repository for bionomic and morphological facts about the parasites for the expert system. The system was developed by using a logic-based computer language which allows the definition of rules and facts to assist the creation of queries to the database. The components of the system are the knowledge base, the multimedia data base, the inference mechanism, and the graphical user interface. The operational modules of the system are the Parasite Identifier and the system Utilities. This expert system facilitates knowledge incorporation in a manner simulating the natural mental process, thus allowing the checking of the accuracy of the information that the user feeds to the computer and the creation of intelligent queries to the database. These characteristics accelerate focusing and optimize the parasite identification scheme regardless of the user's profile of competency. PMID- 9364435 TI - Naturally occurring testis-specific histone H3 antisense transcripts in Drosophila. AB - While analysing the transcription of the cluster of cell-cycle regulated histone genes in Drosophila hydei, we have found transcripts spanned both histone H3 and H4 genes and were antisense for histone H3. As the two histone genes are in opposite orientation, these transcripts contained the sense strand of the histone H4 gene. Such transcripts were present in both poly(A)+ and poly(A)- RNA fractions. The polyadenylated molecules contained a poly(A) tail at the 3' end of the stem-loop structure, which is characteristic for cell-cycle regulated histone mRNAs. The antisense RNA of histone H3 is synthesized exclusively in testes. By developing an improved protocol of in situ hybridization to Drosophila testis squashes, we could demonstrate that the antisense transcripts are localized in the nuclei of primary spermatocytes. Possible functions of this RNA are discussed. PMID- 9364436 TI - De novo methylation of the proto-oncogene, c-fos, during development occurs step wise and directionally in the laboratory mouse. AB - We have analyzed the ontogenic initiation and maintenance of methylation of certain Hpall (m), Hhal (H), Hincll (Hc), and Sall (SI)-specific CpG sites in the coding region of the proto-oncogene, c-fos, through testicular cells, sperm, and fetal, neonatal, and adult somatic tissues. The results show that 1) sperm derived methylated sites get demethylated in early development. However, unlike other studied genes, they remain so at least up to day 13.5 post coitum (pc); 2) de novo methylation proceeds unidirectionally in a step-wise, site-specific manner between m5-m3 sites; 3) the mature, tissue-specific, adult methylation pattern is established between day 0 and day 20 of neonatal development; 4) the Hc and SI sites (CGTCGAC), occurring at an interval of one nucleotide, are only partially methylated in all the tissues; and 5) m3 and H1 sites, which occur close to an Sp1 motif, escape methylation in most of the tissues. The present study on the embryonic gene, c-fos, thus provides a novel pattern of de novo methylation in development. Also, it suggests that close proximity of CpGs may prevent methylation. PMID- 9364437 TI - Regionalized expression of CD52 in rat epididymis is related to mRNA poly(A) tail length. AB - The regional pattern of CD52 expression in the rat epididymis was followed by Northern analyses and carbohydrate-labelling of glycoconjugates on Western blots. CD52 mRNA showed a novel aspect of regionalization, namely region-dependent length differences in its poly(A) tail. 'Short' CD52 mRNA molecules were present in all parts of this organ and also in the seminal vesicles. Additionally, the cauda epididymidis contained mRNA molecules with an extended poly(A) tail. Their appearance coincided with the occurrence of the principal M(r) approximately 26 kDa glycopeptide in the cauda region, representing the CD52 product. CD52 expression seemed to be regulated or modulated synergistically by androgens, temperature, and (an) unknown testicular factor(s), depending on the poly(A) tail length of its mRNA. Androgens alone exerted an effect only on molecules with 'short' poly(A) tails. They were down-regulated in castrated animals, and restored to normal levels upon testosterone supplementation. However, 'long' CD52 mRNA molecules were not affected. Only if combined with the exposure of the epididymis to the elevated temperature of the abdomen, castration of animals resulted in a complete loss of the CD52 mRNA, including the 'long' cauda species. Loss of 'long' CD52 mRNA molecules was also observed when the abdominal location was combined with efferent duct ligation. This combination of treatments, however, did not affect 'short' CD52 mRNA levels. Loss of the 'long' CD52 mRNA molecules by any treatment coincided with a loss of the principal M(r) approximately 26 kDa glycopeptide from caudal protein extracts. PMID- 9364438 TI - Paternal transcripts for glucose-6-phosphate dehydrogenase and adenosine deaminase are first detectable in the human preimplantation embryo at the three- to four-cell stage. AB - The transition between dependence on maternal transcripts and proteins inherited in the oocyte and embryonic gene expression in the human preimplantation embryo occurs at the four- to eight-cell stage. Recently, studies using reverse transcriptase polymerase chain reaction (RT-PCR) have detected paternal transcripts for the Y-linked genes, ZFY and SRY, and the myotonic dystrophy associated protein kinase gene, DK, as early as the late pronucleate one-cell stage. However, expression at the protein level has not been demonstrated and its function at these early stages is unknown. Using coding sequence polymorphisms to distinguish maternal and paternal transcripts, we have examined the transcription of two ubiquitously expressed genes: X-linked glucose-6-phosphate dehydrogenase (G6PD) and adenosine deaminase (ADA). Both G6PD and ADA are housekeeping genes with TATA-less promoters which, because of their roles in metabolism and ubiquitous expression, may provide a more reliable indication of the timing of activation of the embryonic genome. They also each have biallelic polymorphisms with a high heterozygosity ratio which can be detected by restriction digestion. Couples undergoing in vitro fertilization (IVF) were screened for these polymorphisms. Individual spare oocytes and embryos at different stages of preimplantation development were analyzed by RT-PCR and appropriate restriction digestion in those cases in which the male partner carried a different allele to the female partner. In addition, since only female embryos inherit the paternal allele of X-linked G6PD, cDNA was also analyzed for ZFX/ZFY transcripts to identify the sex of each embryo. One hundred and twenty three individual oocytes and embryos were analyzed by RT-PCR and restriction digestion to detect the paternal transcripts from the polymorphic alleles. Maternal transcripts for G6PD, ADA, and ZFX were detected in all oocytes and embryos and at all stages. Following restriction digestion, paternal G6PD and ZFY transcripts were first detected at the four-cell stage and paternal ADA transcripts in an embryo at the three-cell stage coinciding with the onset of dependency on transcription from the embryonic genome. This approach should be widely applicable to other genes since similar polymorphisms exist in the coding regions of many genes. PMID- 9364439 TI - Molecular cloning and sequencing of cDNA encoding for a novel testis-specific antigen. AB - cDNA encoding for a sperm antigen, designated NZ-1, was cloned and sequenced from murine testis cDNA-lambda gt11 expression library using antibodies to human sperm surface antigens belonging to 14-18 kD molecular region. These sperm antigens are involved in zona pellucida binding and have tyrosine phyosphorylation activity. Computer generated translation analysis of 1395-bp cDNA yielded an open reading frame (ORF) of 152 aa with first ATG, Met start codon at nt 32 and the stop codon TGA at nt 487. The translated protein has a calculated molecular weight of 17.9 kD and a potential tyrosine phosphorylation site at aa 46-54, besides at least two O-linked glycosylation sites. The hydropathy plot generated from the deduced aa sequence indicated it to be a membrane-anchored peptide with a hydrophobic NH2 terminus that is characteristic of a signal peptide. Extensive computer search in the GenBank, NBRF, and Swiss sequence banks, indicating it to be a novel protein. Northern blot analysis indicated testis-specific expression of NZ-1 antigen. The NZ-1 cDNA was subcloned into pGEX-1 lambda T vector and expressed in glutathione S-transferase gene fusion system to obtain the recombinant protein. The recombinant protein specifically reacted with the original antibodies raised against the native 14-18 kD sperm proteins. These findings suggest that the sperm specific recombinant NZ-1 may find applications in the development of a contraceptive vaccine, and in studying the normal and abnormal sperm function and the signal transduction mechanism. PMID- 9364440 TI - Molecular cloning, structure, and expression of a testicular follitropin receptor with selective alteration in the carboxy terminus that affects signaling function. AB - During the molecular cloning of the ovine testicular follicle-stimulating (FSH) receptor that couples to the Gs-type effector systems, we discovered novel cDNA clones that were highly homologous. Some of these clones contained an insert of 1,584 bp, which consisted of a divergent 3' region spliced with a 5' region that was identical to nucleotides 724-1,924, forming part of the 9th and 10th exons, of the coding region of the ovine FSH receptor gene. The prominence of alternately spliced clone, which suggested important functional implications, prompted this detailed investigation. Screening of the library by polymerase chain reaction and Northern analysis of testicular messenger RNA with a specific ribo-probe directed to the divergent 3' region of this transcript suggested existence of a full-length transcript of roughly 2.4 kb size. The cDNA was assembled and characterized for its structure. The predicted full-length sequence consisting of nucleotides -121-1,924 of the ovine FSH receptor and the novel 3' region (nucleotides 1,925-2,307) encoded a protein of 670 amino acids containing the entire extracellular and transmembrane domains of the ovine FSH receptor. However, a frame-shift in the coding sequence at the point of divergence resulted in a shorter (40 residues vs. 65 for ovine FSH receptor) C-terminus with three cysteine residues and a reduced number of potential phosphorylation sites. Two of the cysteine residues were adjacent and are apparently potential double palmitoylation sites compared to the single site present in the Gs coupled ovine FSH receptor. Stable expression of this novel transcript in human embryonic kidney (HEK 293) cells revealed the complete absence of cyclic AMP inducible functions, but presence of specific hormone binding activity on plasma membranes and prominent cell surface immunostaining by antireceptor antiserum. There was no alteration in hormone binding specificity because the structurally analogous luteinizing hormone (LH) did not bind to the receptor. The loss of cyclic AMP stimulation in the transfected cells was completely opposite to the properties of the cells expressing the active wild-type receptor. When cells expressing active receptors were cotransfected with the altered FSH receptor cDNA, hormone action was inhibited, suggesting that it could be functioning as a dominant negative receptor. The existence of this ovine FSH receptor with an altered carboxyl terminus predicts the utilization of an alternative splicing mechanism for regulation of receptor expression, signalling and gonadal function. Our study reveals that the modular structure of the FSH receptor gene generates motifs that allows coupling to different effectors. This could become a common feature for all glycoprotein hormone receptors. PMID- 9364441 TI - Alternative splicing converts the G-protein coupled follitropin receptor gene into a growth factor type I receptor: implications for pleiotropic actions of the hormone. AB - Pituitary follitropin (FSH) has pleiotropic actions on gonads, but it is not certain if all these events are mediated by a single receptor. A single gene for the FSH receptor undergoes extensive alternate splicing generating multiple transcripts, and several of these have been cloned and characterized from the sheep testis. In this study we have investigated the expression in HEK (human embryonic kidney) 293 cells of a cloned cDNA encoding the first eight exons of the FSH receptor along with a carboxyterminal extension that contributed a hypothetical single transmembrane domain. This cDNA, which lacked the conventional seven transmembrane motif of the full-length 695 residue wild-type receptor protein, was also efficiently expressed on the cell surface and exhibited high affinity and specificity for FSH binding. LH did not compete for FSH binding indicating that these structures contained all the motifs necessary for specific hormone recognition. Following hormone binding and affinity crosslinking the deduced M(r) of the expressed receptor was compatible with dimer formation. The expression of these altered FSH receptors on the cell surface was confirmed by immunohistochemistry, which revealed punctate labeling in a pattern comparable to that shown by cells transfected by wild-type receptor cDNA. Addition of FSH stimulated 3H-thymidine incorporation in transfected cells in a biphasic manner. By performing RT-PCR we could show that similar altered receptor transcripts were present in both the ovary and testis. Our results reveal for the first time that the seven transmembrane structure of FSH-receptor is not absolutely necessary for cell surface expression and hormone binding provided other compensating motifs are present in the protein structure for membrane insertion. Some of these features are typical of growth factor receptors. Our investigations also demonstrate that alternate splicing of the FSH receptor gene provides a mechanism for creating receptor diversity and suggest that multiple receptors could be involved in regulation of hormone action. PMID- 9364442 TI - Characterization of the 5' flanking region and potential control elements of the ovine follitropin receptor gene. AB - In the preceding two reports, we presented evidence for the structure and functional characteristics of two different, yet related variants of the sheep testicular follicle-stimulating hormone receptor (oFSH receptor) cDNA. To shed further light on the structural basis of the formation of such receptor forms with different motifs and the eventual understanding of gene regulation, we initiated studies to clone the gene. An 8 kb EcoR I fragment containing the exon 1 and 5' flanking sequence was cloned and characterized from among the 14 clones that were isolated from the genomic library. Although not all other clones were fully characterized, we believe that the entire gene of 85-100 kb has been secured as we adopted a successive screening strategy to accommodate currently known alternatively spliced variants of the receptor in this species. This has led us to propose a revised model that includes an 11th exon for the oFSH receptor gene. The 11th exon that lies beyond the currently postulated 10th exon contributes important DNA sequence that results in two different structural/functional motifs. One creates a dominant negative receptor and the other leads to the formation of a growth factor type I receptor for the hormone. In the 2.1 kb 5'-upstream region, there are a number of potentially interesting regulatory elements that resemble sites for estrogen response element (ERE-like), CRE, and orphan receptor (SF-1/ NGF I-A) transcription factors among others. Other interesting features include the presence of potential germ cell specific and methylation sites. By performing primer extension with testicular RNA, we could identify a single major transcription start site at -163 relative to +1ATG. The availability of the structure of FSH-receptor gene in this domestically important seasonal breeder could spur investigations into the control of receptor gene expression. PMID- 9364443 TI - Haploid maternal genome derived from early diplotene oocytes can substitute for the female pronucleus in preimplantation mouse development. AB - We describe the preimplantation development of mouse embryos that have received the haploid maternal genome derived from early diplotene nuclei of primordial oocytes (PO). Two generations of recipient egg-cells were used. Induction of two meiotic divisions of the PO nucleus and the reduction of the number of chromosomes to the haploid level were achieved in preovulatory oocytes (primary recipients). The developmental potential of the obtained haploid genome was examined in zygotes (secondary recipients). The nuclei of PO obtained from newborn mice were transferred by cell electrofusion to in vitro maturing (IVM) and enucleated preovulatory mouse oocytes. The reconstructed oocytes which had completed maturation, i.e., reached metaphase II, were artificially activated (8% ethanol + CHX). Activated oocytes were used as donors of haploid pronuclei of PO origin which were transferred (by karyoplast fusion) to partially enucleated zygotes containing only the male pronucleus. Thus, reconstituted zygotes were transplanted to the ligated oviducts of the cycling mice and 27% of them developed to the blastocyst stage. Our experiments demonstrate that 1) the nucleus of PO can be induced to premature meiotic divisions in an IVM enucleated preovulatory oocyte; 2) in the presence of a normal male pronucleus, the haploid pronucleus of PO origin can substitute for a female pronucleus during preimplantation development. PMID- 9364444 TI - Cryopreservation of mouse embryos affects later embryonic development possibly through reduced expression of the glucose transporter GLUT1. AB - In order to study the effects of cryopreservation on later embryonic development, two-cell mouse embryos were frozen, thawed, and then allowed to develop into blastocysts. The percentage of cryopreserved embryos which developed into blastocysts was significantly lower than that of fresh two-cell embryos. The amount of glucose incorporation in terms of 3H-2-deoxyglucose uptake in blastocysts developed in vivo, and in vitro from fresh or frozen-thawed two-cell embryos, was 473 +/- 108, 105 +/- 75, and 43.0 +/- 28.3 fmol per embryo per hour, respectively. Quantification of glucose transporter GLUT1 in these embryos by Western blotting was reflective of the degree of glucose incorporation. The implantation rate of blastocysts developed in vitro from frozen-thawed two-cell embryos (22.0%) was significantly lower than that developed in vivo (41.1%). These data suggest that cryopreservation may have later consequences on embryonic development through a mechanism that involves altered GLUT1 expression. PMID- 9364445 TI - The developmental origin of primordial germ cells and the transmission of the donor-derived gametes in mixed-sex germline chimeras to the offspring in the chicken. AB - A novel system has been developed to determine the origin and development of primordial germ cells (PGCs) in avian embryos directly. Approximately 700 cells were removed from the center of the area pellucida, the outer of the area pellucida, and the area opaca of the stage X blastoderm (Eyal-Giladi and Kochav, 1976; Dev Biol 49:321-337). When the cells were removed from the center of the area pellucida, the mean number of circulating PGCs per 1 microliter of blood was significantly decreased to 13 (P < 0.05) in the embryo at stage 15 (Hamburger and Hamilton, 1951: J Morphol 88:49-92) as compared to intact embryos of 51. When the removed recipient cells from the center of the area pellucida were replenished with 500 donor cells, no reduction in the PGC number was observed. The removal of cells from the outer of area pellucida or from the area opaca had no effect on the number of PGCs. When another set of the manipulated embryos were cultured ex vivo to hatching and reared to sexual maturity, the absence of germ cells and the degeneration of seminiferous tubules were observed in resulting chickens derived from the blastoderm from which the cells were removed from the center of the area pellucida. Chimeric embryos produced by the male donor cells and the female recipient contained the female-derived cells at 97.2% in the whole embryo and 94.3% in the erythrocytes at 5 days of incubation. At 5-7 days of incubation, masculinization was observed in about one half of the mixed-sex embryos. The proportions of the female-derived cells in the whole embryo and in the erythrocytes were 76.5% and 80.2% at 7 days to 55.7% and 62.5% at 10 days of incubation, respectively. When the chimeras reached their sexual maturity, they were test mated to assess donor contribution to their germline. Five of six male chimeras (83%) and three of five female chimeras (60%) from male donor cells and a female recipient embryo from which 700 cells at the center of area pellucida were removed were germline chimeras. Three of the five male germline chimeras (60%) and one of the three female germline chimeras (33%) transmitted exclusively (100%) donor-derived gametes into the offspring. When embryonic cells were removed from the outer of area pellucida or area opaca, regardless of the sex combination of the donor and the recipient, the transmission of the donor-derived gametes was essentially null. The findings in the present studies demonstrated, both in vivo and in vitro, that the PGCs originate in the central part of the area pellucida and that the developmental fate to germ cell (PGCs) had been destined at stage X blastoderm in chickens. PMID- 9364446 TI - Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and electron microscopy for the characterization of the vitelline coat glycoproteins of the polarized egg of Unio elongatulus. AB - The vitelline coat (VC) glycoproteins of the Unio elongatulus egg, purified as previously described (Focarelli and Rosati, 1993: Mol Reprod Dev 35:44-51) and indicated as gp220 and gp180 by virtue of their apparent molecular weights in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), were analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). The analysis confirmed the purity of our preparations and the mass of gp180, but gave a mass of 273,000 for gp220. Intact VCs and purified VC components were then visualized in stereo images of platinum replicas produced by the quick freeze, deep-etch, and rotary shadowing techniques: gp180 revealed a c-like shape and gp273 a rosette-like shape. The intact VCs were found to consist of two layers, the internal one clearly fibrous and the external one compact. Since purified preparations of gp180 spontaneously formed fibrils of similar width to those present in the inner VC layer, this layer presumably consists mainly of this component. The prevalence of gp273 in the outer layer is also suggested and discussed. PMID- 9364447 TI - Localization and role of sulfoglycolipid immobilizing protein 1 on the mouse sperm head. AB - Sulfoglycolipid immobilizing protein 1 (SLIP 1) is an evolutionally conserved sperm head plasma membrane protein (M(r) = 68 kDa) that binds to sulfogalactosylglycerolipid (SGG), the major sulfoglycolipid present in mammalian sperm. The purpose of this study was to characterize the initial localization and the immunoaggregated relocalization of SLIP1 on the mouse sperm head. Direct immunofluorescence (DF) of live sperm using FITC-antiSLIP1 Fab fragments and FITC antiSLIP1 IgG indicated that SLIP1 was present in the postacrosomal region of the sperm head, although the intensity of immunostaining by FITC-antiSLIP1 IgG was greatest at the border between the postacrosomal region and the acrosome. Unlike that observed with FITC-antiSLIP1 Fab, DF using FITC-antiSLIP1 IgG indicated that SLIP1 was also present in the anterior tip of the sperm head convex ridge. Results from electron microscopic studies, using antiSLIP1 IgG followed by protein A-gold on live mouse sperm, were similar to the DF findings. In contrast, indirect immunofluorescence (IIF) of live mouse sperm using antiSLIP1 IgG and FITC-secondary antibody IgG detected SLIP1 in the sperm head convex ridge only. The IIF and DF results strongly suggest that these bivalent antibodies could induce the sperm antigen relocalization on live sperm heads. SLIP1 redistribution may be dependent on availability of excess SGG, the SLIP1 binding ligand, based on the observation that purified exogenous biotinylated SLIP1 bound to live mouse sperm at both the postacrosomal and convex ridge regions of the mouse sperm head. Immunoaggregation induced by the primary antiSLIP1 IgG or antiSLIP1 Fab with secondary antibody IgG did not cause the acrosome reaction, suggesting that SLIP1 is not involved in sperm signal transduction. Furthermore, postacrosomal SLIP1 was shown to be involved in zona binding, since sperm pretreated with antiSLIP1 Fab fragments (100 micrograms/ml) bound to the egg zona pellucida in vitro at approximately 35% of control levels. PMID- 9364448 TI - A fertilization promoting peptide (FPP)-related tripeptide competitively inhibits responses to FPP: a cause of male subfertility? AB - Fertilization promoting peptide (FPP; pGlu-Glu-ProNH2), a tripeptide structurally related to thyrotrophin releasing hormone (TRH; pGlu-His-ProNH2), is present in the prostate gland and seminal plasma of several mammalian species. FPP has been shown not only to stimulate the capacitation and fertilizing ability of epididymal mouse and ejaculated human spermatozoa, but also to inhibit spontaneous acrosome loss in mouse spermatozoa. These results suggest a possible role in vivo for FPP to maximize the fertilizing potential of the few cells that reach the ampulla. In this study we have investigated the effects of FPP-related peptides on mouse sperm capacitation and the acrosome reaction (using chlortetracycline fluorescence) and in vitro fertilizing ability. Deamidated FPP neither stimulated capacitation when tested at 50-200 nM nor interfered with FPP's stimulation of capacitation. Three neutral peptides (pGlu-Phe-ProNH2, MeO FPP, pGlu-Gln-ProNH2) were also evaluated. pGlu-Phe-ProNH2, slightly stimulatory when used alone, had no additive effect when used in combination with FPP and the methyl derivative of FPP had no bioactivity itself and did not inhibit responses to FPP. In marked contrast, pGlu-Gln-ProNH2 (Gln-FPP), which had no bioactivity when added to uncapacitated suspensions at 50-100 nM, significantly inhibited FPP's stimulation of capacitation and fertilizing ability in vitro. Furthermore, when Gln-FPP + FPP were added to capacitated suspensions, Gln-FPP prevented FPP's inhibition of spontaneous acrosome loss. Our recent studies have indicated that FPP and adenosine can elicit similar responses but appear to act at different sites. The fact that Gln-FPP inhibited responses to FPP, but not to adenosine, indicates that Gln-FPP is acting at an FPP-specific site. We, therefore, conclude that the specific structure of the FPP molecule is crucial for biological activity. Removal of the terminal amide group abolishes bioactivity and changes to the central amino acid can have significant functional consequences. Since Gln FPP is a candidate intermediate peptide in the FPP biosynthetic pathway and has been identified in human semen, abnormality in prostate function could lead to release of Gln-FPP along with, or instead of, FPP. Our results suggest that the relative proportions of FPP and related peptides in seminal plasma could have a significant effect on fertility in vivo. PMID- 9364449 TI - Cytokeratin cytoskeleton in the differentiating ovarian follicle of the lizard Podarcis sicula Raf. AB - By immunoblotting and immunocytochemical techniques, we characterized the cytokeratins previously localized by us in the previtellogenic ovarian follicle of Podarcis sicula. Our results show that these cytokeratins correspond to those expressed in the monolayered epithelia. In fact, the immunoblotting analysis showed that the NCL-5D3 antibody, specific for human low molecular weight cytokeratins expressed in monolayered epithelia, reacted with the cytokeratins extracted both from the ovary and from the monolayered intestinal mucosa of Podarcis sicula. Furthermore, this antibody, in this reptile as in humans, clearly immunolabeled sections of corresponding tissues. The organization of the cytokeratin cytoskeleton in the main steps of the ovarian follicle differentiation was also clarified. The reported observations suggest that in Podarcis sicula, the cytokeratin cytoskeleton is absent in the early oocytes. It first appears in the growing oocytes as a thin cortical layer in concomitance with its becoming visible also in the enlarging follicle cells. In the larger follicles, this cytoskeleton appears well organized in intermediate cells and in particular in fully differentiated pyriform cells. In both these cells a cytokeratin network connects the cytoplasm to the oocyte cortex through intercellular bridges. At the end of the previtellogenic oocyte growth, the intense immunolabeling of the apex in the regressing pyriform cells suggests that the cytokeratin, as other cytoplasmic components, may be transferred from these follicle cells to the oocyte. At the end of the oocyte growth, in the larger vitellogenic oocytes surrounded by a monolayer of follicle cells, the cytokeratin constitutes a heavily immunolabeled cortical layer thicker than in the previous stages. PMID- 9364450 TI - Protein tyrosine phosphorylation: implications for synaptic function. AB - The phosphorylation of proteins on tyrosine residues, initially believed to be primarily involved in cell growth and differentiation, is now recognized as having a critical role in regulating the function of mature cells. The brain exhibits one of the highest levels of tyrosine kinase activity in the adult animal and the synaptic region is particularly rich in tyrosine kinases and tyrosine phosphorylated proteins. Recent studies have described the effects of tyrosine phosphorylation on the activities of a number of proteins which are potentially involved in the regulation of synaptic function. Furthermore, it is becoming apparent that tyrosine phosphorylation is involved in the modification of synaptic activity, such as occurs during depolarization, the induction of long term potentiation or long-term depression, and ischemia. Changes in the activities of tyrosine kinases and/or protein tyrosine phosphatases which are associated with synaptic structures may result in altered tyrosine phosphorylation of proteins located at the synapse leading to both short-term and long-lasting changes in synaptic and neuronal function. PMID- 9364451 TI - Phosphorylation of receptors and ion channels and their interaction with structural proteins. PMID- 9364452 TI - A new twist in an old story: the role for crosstalk of neuronal and trophic activity. AB - A number of recent findings suggest a reciprocal interaction between neurotransmitters and neurotrophins functioning at the level of the synapse, which may be relevant not only for plasticity changes in the mature nervous system, but also for the development of synaptic connectivity and for survival or maturation of neurons prior to target contact. Thus, neurotrophin-induced attenuation of frequency-dependent depletion of releasable synaptic vesicle pools of neurotransmitter at synapses may participate in Hebbian and non-Hebbian forms of LTP, as a characteristic of mature synaptic contacts. Subsequent to nerve/target contact, neurotrophins also appear to mediate contact-induced enhancement of neurotransmitter release; this may participate in a developmental improvement of synapse efficacy, stabilization of synaptic contacts, and maturation of "conductive" functional synapses. Coincident with a transmitter induced elevation of cytosolic Ca2+ levels within growth cones, a local neurotrophin-mediated increase in released neurotransmitter occurring subsequent to stabilization of a distinct synaptic contact may then participate in the refinement of synapses with retention of those neurites affected by neurotrophins and withdrawal of those neurites not affected by neurotrophins. Finally, prior to nerve/target contact, Ca2+ channel-generated spontaneous neuronal activity as well as co-expression of neurotrophins and their receptors may play a role in maturational changes. PMID- 9364454 TI - Effect of L-glutamate on cholinergic neurotransmission in various brain regions and during the development of rats, when administered perinatally. AB - Glutamate, as a monosodium salt (MSG) has neurotoxic effects on some brain regions when systemically given to young rats. Few studies have been conducted to establish the mechanisms involved in studying neurotoxicity resulting in neuronal death by glutamate (Glu) and its effects as related to different brain neuropathologies under in-vivo conditions and where the cholinergic system shows vulnerability. Thus, this paper aims to evaluate the binding kinetics of quinuclynidyl benzylate (QNB) to muscarinic receptors for acetylcholine and the activity of choline acetyltransferase (CAT) in rats treated with MSG (4 mg/g on days 1, 3, 5, and 7 after birth) during the rat development stages (days 14, 21, 30, and 60) in different brain regions. The results show that perinatal treatment with MSG significantly decreases the CAT activity and increases the affinity of [3H]-QNB and the number of receptors of the brain cortex during the ages studied. The striatum showed increased CAT activity and BMAX on days 30 and 60 after birth. Affinity and the number of receptors increased in the hippocampus only between days 21 through 60 after birth. NaCl given at MSG equimolar doses only modified the CAT activity but had no effect on the [3H]-QNB binding kinetics in any of the regions studied. The results show that MSG alters cholinergic neurotransmission in the central nervous system (CNS) and induces the development of compensating events suggesting an involvement in neuronal plasticity during the development of rat CNS. PMID- 9364453 TI - Neurotoxin domoic acid produces cytotoxicity via kainate- and AMPA-sensitive receptors in cultured cortical neurones. AB - Domoic acid, a naturally occurring kainoid, has been responsible for several outbreaks of fatal poisoning after shellfish ingestion, and we examined its neurotoxic mechanism in cultured murine cortical neurones. Using observations of neuronal viability and morphology, exposure to domoic acid for 24 h was found to induce substantial concentration-dependent neuronal cell death. Domoic acid mediated neuronal death was attenuated by the non-N-methyl-D-aspartate receptor antagonist 6-cyano-7-nitro-quinoxaline-2,3-dione and the alpha-amino-3-hydroxy-5 methylisoxazole-4-propionate (AMPA) receptor-selective antagonist LY293558 ((3S,4aR,6R,8aR)-6-[2-(1H-tetrazol-5-yl)-ethyl]-1,2,3, 4,4a,5,6,7,8,8a decahydroisoquinoline-3-carboxylic acid), but unaffected by NS-102 (5-nitro 6,7,8,9-tetrahydrobenzo[g]indole-2, 3-dione-3-oxime)--a low-affinity kainate receptor antagonist. Domoic acid was equipotent with (S)-AMPA (EC50 values 3.8 and 3.4 microM respectively); however, (S)-AMPA induced only 50% cell death compared to > 80% cell death induced by domoic acid. Kainate also killed > 80% of cortical neurones; however, domoic acid was about 19 times more potent than kainate (EC50 75 microM). We show the potent neurotoxicity of domoic acid for the first time in a pure neuronal model and indicate that domoic acid acts via high affinity AMPA- and kainate-sensitive glutamate receptors to produce excitotoxic cell death. PMID- 9364456 TI - Increased expression of peripheral benzodiazepine receptors in the facial nucleus following motor neuron axotomy. AB - Peripheral benzodiazepine receptors (PBRs) are expressed in a variety of tissues but are normally found at low levels in the brain. Following various types of nerve injury, a reactive gliosis results that exhibits a high expression of this receptor. To further characterize the expression of PBRs following neuronal injury, we evaluated PBR expression in the facial nucleus following facial nerve axotomy (FNA). Injury to a peripheral nerve results in a complex series of metabolic and morphological changes around the injured neuron. Transections of the facial nerve results in a rapid activation of both astrocytes and microglia around axotomized motor neurons. FNA resulted in an increase in the staining for both astrocytes (glial fibrillary acidic protein) and activated microglia (OX42). There was also a reduction in synaptic contacts with the motor nucleus as evidenced by reduced staining for the synaptic marker, synaptophysin. In sections labeled with [3H]-PK11195, the subsequent autoradiograms displayed marked increases in the labeling for PBRs. This increase was observed at 5, 7 and 10 days after nerve transection. The increase was primarily in the level of expression (Bmax), with no change in the affinity of the ligand (Kd). The increase in PBR expression after FNA supports the hypothesis that PBRs can be used as a sensitive marker for CNS injury. PMID- 9364455 TI - Repeated administration of tacrine to normal rats: effects on cholinergic, glutamatergic, and GABAergic receptor subtypes in rat brain using receptor autoradiography. AB - Tacrine, a potent acetylcholinesterase inhibitor, has been reported to improve cognitive function in patients with Alzheimer's disease. The present investigation was conducted to elucidate in vivo any interaction between tacrine induced cortical cholinergic hyperactivity and glutamatergic and GABAergic neurotransmission, which might influence the therapeutic potential of tacrine. Seven days after a daily dosage of 10 mg/kg tacrine i.p. quantitative receptor autoradiography was performed in coronal sections throughout the brain. Repeated administration of tacrine resulted in decreased binding to high-affinity choline uptake, nicotinic and M2-muscarinic acetylcholine receptor sites in a number of cortical regions, while reductions in M1-muscarinic receptor binding were restricted to the cingulate and entorhinal cortex as well as caudate-putamen. Moreover, tacrine injections decreased cortical AMPA receptor binding throughout the brain, while NMDA, kainate, and GABAA receptor binding remained unchanged. Tacrine administration alters cortical AMPA receptor binding in the opposite direction to that observed in patients with Alzheimer's disease, suggesting that tacrine may exert a reversal in up/down-regulation of cortical glutamate receptor subtypes in Alzheimer patients. However, the drug-induced reductions in cortical high-affinity choline uptake sites as well as in nicotinic and in muscarinic acetylcholine receptor binding might partially counteract the cognition-enhancing effects of tacrine produced by acetylcholinesterase inhibition. PMID- 9364457 TI - Kainate excitotoxicity is mediated by AMPA- but not kainate-preferring receptors in embryonic rat hippocampal cultures. AB - We investigated kainate-induced excitotoxicity in embryonic rat hippocampal cells cultured in a chemically defined medium. Treatment with kainate for 24 h resulted in neuronal death, as assessed by the release of lactate dehydrogenase into the culture media. This neurotoxic effect was kainate dose- and culture age dependent. EC50 of kainate was 127 +/- 11 microM. 2,3-dihydroxy-6-nitro-7 sulfamoylbenzo (f)quinoxaline (NBQX) completely blocked the toxicity, while MK801, an N-methyl-D-aspartate (NMDA) receptor antagonist, also blocked it but not completely. Furthermore, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) attenuated the kainate injury, while the selective and noncompetitive AMPA-preferring receptor antagonist 1-(4-aminophenyl)-4-methyl-7, 8 methylenedioxy-5H-2,3-benzo-diazepine (GYKI 52466) blocked it completely. Concanavalin A (ConA), which potentiates the response to kainate at kainate preferring receptors, had little effect on kainate toxicity. Further, AMPA alone induced little toxicity, but produced remarkable toxicity when cyclothazide was used to block the desensitization of AMPA-preferring receptors. These results indicate that kainate excitotoxicity in hippocampal cultures is mediated by AMPA- but not kainate-preferring receptors, and that it involves NMDA-receptor-mediated toxicity. The non-desensitizing response at AMPA-preferring receptors may play an important role in kainate-induced excitotoxicity. PMID- 9364459 TI - Possible involvement of intracellular Ca2+ in hyposmosis-evoked catecholamine release from adrenal chromaffin cells. AB - The influence of hyposmotic conditions on catecholamine release was studied using cultured adrenal chromaffin cells. Incubation of the cells in hyposmotic solution led to the enhancement of catecholamine release in a manner dependent on the reduction of osmolarity. Hyposmosis-evoked catecholamine release was similarly observed in the presence or absence of extracellular Ca2+, and was not significantly affected by organic and inorganic Ca2+ entry blockers. These results indicated that the hyposmosis-evoked release might be associated with a rise in the intracellular Ca2+ concentration. Further studies showed that neither ryanodine nor thapsigargin caused any significant effect on hyposmosis-evoked catecholamine release, whereas pretreatment of chromaffin cells with carbonyl cyanide m-chlorophenyl hydrazone significantly enhanced the hyposmosis-evoked release. Catecholamine release evoked by exposure to hyposmotic medium is therefore thought to be mediated through intracellular Ca2+, which may be mainly sequestered by the mitochondrial pools. Neither caffeine- nor inositol 1,4,5 trisphosphate-sensitive Ca2+ pools seems likely to be involved in hyposmosis evoked catecholamine release, although the Ca2+ pools that contribute to the elevation of intracellular Ca2+ observed under hyposmotic conditions are not yet completely identified. PMID- 9364458 TI - Ventral and dorsal striatal cholinergic neurons have different sensitivities to kainic acid. AB - The present study was conducted to investigate the sensitivity of the cholinergic elements of ventral and dorsal striatal regions of the rat brain to the neurotoxin kainic acid (KA). Cholinergic activity was assessed by determining choline-acetyltransferase activity (CAT) and by measurements of acetylcholine (Ach) release from slices prelabeled with [3H]-choline. Direct stereotaxic injections of high-dose KA (4 micrograms/2 microliters) into specific brain regions, reduced CAT in caudate putamen (CP) by 91 +/- 1%, in nucleus accumbens (Nac) by 71 +/- 6%, but CAT in the olfactory tubercle (OT) was not affected by KA. The effects of KA on CP CAT were dose- and volume-dependent. In the OT, KA failed to affect CAT at low, moderate or high doses. Slices obtained from CP injected with KA (3 days prior) showed a 90% reduction in the electrically evoked release of [3H]-transmitter release; however, KA had no effect on transmitter release from OT. These results indicate that KA spares the cholinergic elements of the OT, and reveal the existence of marked differences in excitotoxic action of KA between ventral and dorsal striatal regions and among regions of the ventral striatum. Kainic acid preferentially damages neuronal cell bodies, dendrites and terminals intrinsic within the structures injected, with little or no effect on afferent axons and terminal boutons. Therefore, we propose that most of the Ach present in the OT may be within afferent axons and axon terminals. In the CP and NAc, KA lesions reflect loss of intrinsic cholinergic neurons. In addition, variable levels of excitatory inputs and of excitatory receptors, of the mechanisms available to reduce elevated intracellular calcium concentrations and of the levels of free-radical scavenging resources, also could account for the differences in KA neurotoxicity between OT and CP. PMID- 9364460 TI - Selective damage to the cerebellar vermis in chronic alcoholism: a contribution from neurotoxicology to an old problem of selective vulnerability. AB - The curiously consistent localization of cerebellar cortical damage in chronic alcoholism is re-evaluated in the light of selective damage, with a similar topography in the cerebellar vermal region, in superficial siderosis in man and in experimental animals exposed to certain toxic substances. Attention is drawn to the capacity for Purkinje cell dendrites and Bergmann glia to extract materials from the CSF, and to the close anatomical relationships of the susceptible lobules I-II, IX and X to the roof of the IVth ventricle and to the cistern of the great cerebral veins. This restriction of damage to vermis and paravermis may reflect some compartmentalization of CSF flow within leptomeninges, consistently increasing exposure of these cerebellar surfaces to materials circulating in the CSF. In other circumstances when this pattern of damage is encountered it raises the question as to whether other environmental agents, gaining access to the CSF, may be similarly distributed. PMID- 9364461 TI - Acrylamide and 2,5-hexanedione induce collapse of neurofilaments in SH-SY5Y human neuroblastoma cells to form perikaryal inclusion bodies. AB - Neurofilament accumulations are characteristic of a number of neurological conditions including amyotrophic lateral sclerosis, giant axonal neuropathies and several chemically-induced neuropathies. Although the mechanism(s) leading to neurofilament accumulation are unknown, it is possible that similar processes occur both in disease and in chemically-induced neuropathies. Understanding the mechanism(s) of chemically-induced neurofilament accumulation, which is more amenable to experimental manipulation, may give insight into the neurological diseases they mimic. We have compared the effects of two chemically-dissimilar neurotoxins, 2,5-hexanedione and acrylamide, on neurofilaments in the human neuroblastoma cell line, SH-SY5Y. Both undifferentiated and differentiated SH SY5Y cells were exposed to 2,5-hexanedione or acrylamide and changes in cytoskeletal organization examined by immunofluorescence and electron microscopy. Although distinct morphological differences have previously been characterized in the neuropathies induced by 2,5-hexanedione and acrylamide in vivo, we have found that both compounds had similar direct effects on neurofilaments in SH-SY5Y cells, inducing formation of perikaryal inclusion bodies. In addition, differentiated SH-SY5Y cells were more sensitive to both 2,5-hexanedione and acrylamide compared with undifferentiated cells. These similar effects of 2,5 hexanedione and acrylamide lend further support that a common mechanism(s) may lead to neurofilament accumulation in these neuropathies. SH-SY5Y cells provide a useful model to investigate further the biochemical basis of neurofilament accumulation. PMID- 9364462 TI - Effect of changes in the CD44 gene on tumour cell invasion in gliomas. AB - Cell adhesion is a critical factor in the multistep process of tumour invasion. CD44 is one of the cell surface adhesion molecules responsible for interaction with hyaluronic acid, a component of the CNS extracellular matrix. The aim of the present study was to demonstrate whether alterations in the CD44 gene might account for different invasive behaviour. EcoRI restriction analysis by Southern blot hybridization revealed several additional hybridization signals in tissue specimens of two out of 16 patients with glioblastoma, indicating DNA rearrangements or point mutations, respectively, within the region of the CD44 gene. Expression patterns of CD44 isoforms in these two rearranged gliomas and in 28 other patients with malignant gliomas were analysed by RT-PCR. All cases displayed only the splice variant CD44H, which acts as hyaluronic acid receptor in glioma tumour cells. Tumour cell invasion was studied with Boyden chamber assays using hyaluronic acid as ligand and functional CD44H blocking antibody. Invasion of cells derived from those gliomas carrying the rearranged CD44 gene locus was decreased by about 50% compared with gliomas without rearrangement, indicating that the altered hybridization patterns in the two glioma samples influenced CD44H mediated glioma cell invasion through hyaluronic acid in vitro. Our results on CD44 isoform expression suggest that, in contrast to other solid tumours, gliomas seem to express only the CD44 variant. Genetic alterations within the CD44 gene might alter the binding domain of the receptor and thus account for different invasive behaviour in glioblastomas. PMID- 9364463 TI - Human neoplastic Schwann cells: changes in the expression of neurotrophins and their low-affinity receptor p75. AB - Neurotrophins are known to influence Schwann cells during development and to promote peripheral nerve regeneration after axonal damage. In neoplastic conditions. Schwann cells from experimentally-induced schwannomas appear to retain their responsiveness to nerve growth factor (NGF), although the role of neurotrophins in the neoplastic process in poorly understood. In this study, human neoplastic Schwann cells (five cases of acoustic schwannoma and two cases of malignant peripheral nerve sheath tumours [MPNST]) were investigated for the expression in situ of molecules of the neurotrophin system. In particular, we studied the 75 kDa low-affinity receptor (p75) and the mRNA for its ligands, NGF and neurotrophin-3 (NT-3). By immunohistochemistry, the p75 receptor was found to be the present at high levels in Schwann cells from acoustic schwannomas, whereas it was very weak or absent in MPNST. Messenger RNA for NGF and NT-3 was detected by reverse transcriptase in situ polymerase chain reaction technique and showed the same fluctuation of p75, being up-regulated in acoustic schwannomas and very weak or absent in MPNST. In normal non-neoplastic tissue, no detectable amounts of either ligand or receptor were observed. Our results indicate that changes in the expression of neurotrophins and their p75 receptor occurred during the neoplastic transformation of Schwann cells. In benign schwannomas, such changes are likely to reflect the loss of axonal contact, while in MPNST they may be related to a complete derangement of cell machinery in the tumour cells. PMID- 9364464 TI - Peripheral nerve regeneration through nerve guides seeded with adult Schwann cells. AB - This study tested the usefulness of Schwann cells in the repair of a severed nerve with a biosynthetic bridge or guide. Reinforced collagen nerve guides were used to bridge an 18 mm gap in the sciatic nerve of 21 young adult rats. The animals were divided into three groups and the guides were filled with: (i) more than 0.5 x 10(6) cultured syngeneic adult Schwann cells (group L, n = 12); (ii) less than 0.5 x 10(6) Schwann cells (Group S, n = 6); and (iii) phosphate buffered saline (control, n = 3). Schwann cells were pre-labelled with Hoechst dye. Regeneration was assessed functionally and histologically at 1, 2, 3 and 6 + months after surgery. Group L animals showed numerous regenerated axons surrounded by implanted Schwann cells within the first month. The total number of myelinated fibers (12.5 x 10(3)) remained above normal unoperated values (7 x 10(3)) in long-term animals. Regenerated axons were found in Group S in the third month, but no Hoechst labelled cells were found. The number of myelinated fibers (3.9 x 10(3)) remained below normal values in long-term animals. Control guides failed to support axonal regeneration. Functional recovery was evident at week 20 (Group L) and week 30 (Group S) after surgery, with no difference in function between the two groups by the end of the study. Supplementing guides with Schwann cells enhances regeneration of peripheral axons over a distance normally prohibitive. This effect is greatest in the early stages of regeneration (1-3 months) and is dependent on the number of cells implanted. PMID- 9364466 TI - Differential matrix metalloproteinase expression in cases of multiple sclerosis and stroke. AB - Multiple sclerosis (MS) and stroke pathology are characterized blood-brain barrier breakdown, leucocyte emigration, and tissue destruction. Each process is thought to involve the matrix metalloproteinases (MMP), but little is known of their expression. We undertook to investigate whether MMP expression is dependent on the nature of the CNS lesion and whether expression would coincide with the histopathology. MS or cerebral-infarct tissue was examined for the presence of gelatinase-A, gelatinase-B, matrilysin and stromelysin-1. Gelatinases A and B and matrilysin expression was found to be up-regulated in microglia/macrophages within acute MS lesions. In active-chronic MS lesions, matrilysin and gelatinase A expression was pronounced in the active borders. In chronic MS lesions, the expression of matrilysin was confined to macrophages within perivascular cuffs. The pattern of MMP expression in infarct lesions differed considerably. Gelatinase-B was strongly expressed by neutrophils in tissue from patients up to 1 week after an infarct, whereas gelatinase-A and matrilysin staining was much less marked. From 1 week to 5 years, neutrophils were absent and the large number of macrophages present were expressing matrilysin and gelatinase A. Only a low level of gelatinase-A and matrilysin expression was observed in normal brain controls. Thus, MMPs are expressed in inflammatory lesions in the CNS, but their individual expression is dependent on the nature and chronicity of the lesion. However, the general pattern of expression, in perivascular cuffs and in active lesions, supports a role for these enzymes as mediators of blood-brain barrier breakdown and tissue destruction, both in MS and in cerebral ischaemia. PMID- 9364465 TI - The abnormal expression of utrophin in Duchenne and Becker muscular dystrophy is age related. AB - Utrophin is a 395 kDa protein with considerable homology to dystrophin. It is highly expressed in the sarcolemma of normal fetal muscle fibres but is confined to neuromuscular and myotendinous junctions, and blood vessels in adult muscle. Sarcolemmal expression occurs on regenerating fibers, irrespective of the disease, and is also seen on mature fibres in Duchenne and Becker muscular dystrophies (DMD, BMD), and inflammatory myopathies. The reasons for the abnormal expression in DMD and BMD are unclear. We have studied this expression of utrophin immunocytochemically on mature fibres in 42 cases of DMD and BMD, aged 3 months-24 years of age. All cases had some mature fibres, with no detectable fetal myosin, that showed sarcolemmal expression of utrophin. The number of these fibers and the intensity of fluorescence was low in young cases before the age of 2 years and increased with age. The fluorescence was graded on a scale of 0 to ++ ++ and there were significantly more cases under 2 years of age (10/12) with a grading of utrophin of only +, compared with those over 2 years (4/30, P < 0.001). Some revertant fibres, but not all, expressed utrophin and dystrophin. Our data show that the abnormal expression of utrophin on mature muscle fibres in DMD and BMD is not a continuation of the expression that occurs in fetal or regenerating muscle, but is a secondary event caused by unknown factors. The immunocytochemical intensity of utrophin is variable between cases and there is no correlation with clinical severity. As all cases studied had some expression of utrophin on mature fibres, this may be a useful additional tool for distinguishing BMD from other dystrophies, especially in cases with minimal abnormalities in dystrophin expression and/or no detectable mutation in the gene. PMID- 9364467 TI - The human prion diseases: from neuropathology to pathobiology and molecular genetics. Final report of an EU concerted action. PMID- 9364468 TI - The past, present and future of purine nucleotides as signalling molecules. PMID- 9364469 TI - Structure-function analysis of inhibitory adenosine receptor regulation. AB - Pharmacological and molecular cloning studies have revealed the presence of four adenosine receptor (AR) subtypes, termed A1, A2A, A2B and A3. Given that the A1 and A3ARs can both bind adenosine and couple productively to inhibitory G proteins, the significance of the existence of multiple inhibitory AR subtypes remains obscure, although one possibility is that these receptors are regulated in a subtype-specific manner. In this review, we summarize our investigations into the mechanisms underlying the agonist-induced desensitization of inhibitory AR function. The results of this work demonstrate that while the A1AR desensitizes slowly over a time course of several hours, the A3AR desensitizes within minutes of agonist exposure. Molecular biological studies have begun to delineate the structural requirements responsible for these differences, and will provide a basis for future experiments designed to determine whether the ability of an inhibitory AR receptor subtype to 'turn-off' at a specific rate has implications for the physiological role of that receptor. PMID- 9364470 TI - Purines and their roles in apoptosis. AB - Purines are ubiquitous endogenous metabolites, and their roles as signalling molecules, especially in the case of adenosine and ATP, are well documented. The release of purines is increased when cells are highly activated, stressed or damaged, and this is known to have profound effects on various organ systems. Recently, purines like adenosine and ATP have been shown to be cytotoxic. Current evidence suggests that adenosine induces cell death by apoptosis, whereas ATP appears to cause both necrosis and apoptosis. Apoptosis is an important physiological process during normal tissue turnover and in the maturation of the immune system, embryogenesis, metamorphosis, endocrine-dependent tissue atrophy, etc. Recently, many of the key components of the apoptotic cell death cascade have become unravelled. In particular, proteases belonging to the interleukin-1 beta-converting (ICE) enzyme family, also known as caspases, have been shown to act as an intracellular convergence point that orchestrates the morphological and biochemical features of apoptosis. However, little is known about the signalling or the biochemical mechanisms of purine-mediated cell death. Adenosine appears to act through P1 purinoceptors, although the subtype involved remains controversial, whereas ATP may involve both P2X1 and P2X7 purinoceptors. More recent evidence suggests that the intracellular levels of purines, in addition to the cell surface receptor-mediated responses, may also play a critical role by modulating other apoptotic cell death signals. Here, we review our current understanding about purines in mediating cell death and raise a number of questions as to the possible mechanisms involved. PMID- 9364471 TI - Pharmacological characterization of novel A3 adenosine receptor-selective antagonists. AB - The effects of putative A3 adenosine receptor antagonists of three diverse chemical classes (the flavonoid MRS 1067, the 6-phenyl-1,4-dihydropyridines MRS 1097 and MRS 1191, and the triazoloquinazoline MRS 1220) were characterized in receptor binding and functional assays. MRS1067, MRS 1191 and MRS 1220 were found to be competitive in saturation binding studies using the agonist radioligand [125I]AB-MECA (N6-(4-amino-3-iodobenzyl)adenosine-5'-N-methyluronamide) at cloned human brain A3 receptors expressed in HEK-293 cells. Antagonism was demonstrated in functional assays consisting of agonist-induced inhibition of adenylate cyclase and the stimulation of binding of [35S]guanosine 5'-O-(3 thiotriphosphate) ([35S]GTP-gamma-S) to the associated G-proteins. MRS 1220 and MRS 1191, with KB values of 1.7 and 92 nM, respectively, proved to be highly selective for human A3 receptor vs human A1 receptor-mediated effects on adenylate cyclase. In addition, MRS 1220 reversed the effect of A3 agonist elicited inhibition of tumor necrosis factor-alpha formation in the human macrophage U-937 cell line, with an IC50 value of 0.3 microM. PMID- 9364472 TI - Molecular identification of the equilibrative NBMPR-sensitive (es) nucleoside transporter and demonstration of an equilibrative NBMPR-insensitive (ei) transport activity in human erythroleukemia (K562) cells. AB - Equilibrative nucleoside transport processes in mammalian cells are categorized as either nitrobenzylthioinosine (NBMPR)-sensitive (es) or NBMPR-insensitive (ei). Inhibition of the es process arises from binding of NBMPR to a high affinity site(s) on the es transporter that can be identified by photoaffinity labeling with [3H]NBMPR. This study examined the equilibrative nucleoside transport processes of cultured human erythroleukemia (K562) cells. The presence of NBMPR binding sites (4.8 +/- 0.9 x 10(5)/cell, Kd = 0.3 nM), together with the identification of polypeptides by specific photolabeling of membranes with [3H]NBMPR, indicated that K562 cells possess es nucleoside transporters (ca 500,000 copies/cell). The photolabeled polypeptides of K562 cells migrated with lower relative mobility (peak M(r) value, 63,000) than did those of human erythrocytes (peak M(r) value, 53,000). This difference in apparent M(r) was abolished by prolonged treatment of membrane proteins with N-glycosidase F, suggesting that equilibrative nucleoside transport in K562 cells and erythrocytes is mediated by the same, or a closely related, es isoform. A cDNA encoding the es nucleoside transporter of human placenta (termed hENT1) was recently isolated by a strategy based on the N-terminal sequence of the es transporter of human erythrocytes. hENT-like mRNA species were detected in K562 cells, as well as in several other human cell lines of neoplastic origin (A459, G361, HeLa, HL-60, Molt-4, Raji, SW480), by high-stringency northern analysis with a placental hENT1 probe. A cDNA that encoded a protein identical to hENT1 was isolated by reverse transcriptase polymerase chain reaction with primers specific for hENT1. NBMPR inhibited zero-trans influx of 3H-labeled adenosine, uridine and thymidine by 50% (IC50 values) at 0.4-1.0 nM, confirming the presence of an NBMPR-sensitive (es) transport process, which accounted for 80-90% of total transport activity. The remaining component was identified as the equilibrative NBMPR-insensitive (ei) transport process since it: (i) exhibited low (IC50 > 1.0 microM) sensitivity to NBMPR; (ii) was not concentrative; and (iii) was unchanged by elimination of the sodium gradient. The kinetic parameters (determined at 37 degrees C) for the es- and ei-mediated processes differed markedly. Values for transport of uridine by the es- and ei-mediated processes were, respectively: K(m) = 229 +/- 39 and 1077 +/- 220 microM; Vmax, 186 +/- 31 and 40 +/- 5 pmol/microliter cell water/sec. Values for transport of adenosine by the es and ei-mediated processes were, respectively, 61 +/- 9 and 133 +/- 17 microM; Vmax, 70 +/- 5 and 23 +/- 8 pmol/microlitere cell water/sec. The ei-mediated process, although small, was of pharmacologic importance since K562 cells could not be protected by NBMPR (10 microM) from the cytotoxic effects of tubercidin (7-deazaadenosine). PMID- 9364473 TI - HEK293 human embryonic kidney cells endogenously express the P2Y1 and P2Y2 receptors. AB - Adenine and uridine nucleotide-promoted inositol phosphate accumulation was studied in HEK293 cells. Concentration effect curves for ADP, ATP, and 2ClATP were complex and could be resolved by a two-site model into low and high potency components, suggesting the involvement of two receptors. The maximal effect observed for the P2Y1 receptor-selective agonists 2MeSATP and 2MeSADP was 65-70% of that observed with ATP, ADP, or 2ClATP, and the concentration effect curves for these two analogs were consistent with their interaction at a single site. The P2Y1 receptor-selective antagonist PPADS completely blocked 2MeSATP stimulated inositol phosphate accumulation, but only partially antagonized the response to ATP. UTP also was an agonist, but the maximal effect observed was approximately 25% of that observed with ATP or ADP. In the presence of maximally effective concentrations of UTP, the concentration effect curves to 2C1ATP and ADP followed law of mass action interaction at a single site, and their maximal elevation of inositol phosphate accumulation was equivalent to that observed with 2MeSATP and 2MeSADP. The order of potency of adenine nucleotide agonists in the presence of a maximally effective concentration of UTP was consistent with that for interaction with a P2Y1 receptor. Thus, HEK293 cells apparently express two subtypes of P2Y receptors that respond to ADP or ATP in an additive manner: a P2Y1 receptor, which is selectively activated by 2MeSADP, and a P2Y2 receptor, which is selectively activated by UTP. PMID- 9364474 TI - An ecto-ATPase and an ecto-ATP diphosphohydrolase are expressed in rat brain. AB - Extracellular nucleotides acting as signaling molecules are inactivated by hydrolysis catalyzed by ecto-nucleotidases. ATP is sequentially degraded via ADP and AMP to adenosine. Enzymes that can be involved in the extracellular hydrolysis chain are ecto-ATP diphosphohydrolase (ecto-apyrase), ecto-ATPase, ecto-ADPase and 5'-nucleotidase. Mammalian ecto-ATP diphosphohydrolase is a member of a family of apyrases sharing four "apyrase conserved regions" that presumably participate in the formation of the catalytic site. We report the presence of ecto-ATP diphosphohydrolase in rat brain and the primary structure of a new mammalian member of the apyrase family. Expression in CHO cells shows that it represents an ecto-ATPase. As revealed by Northern analysis of rat tissues, the ecto-ATPase is co-expressed with ecto-ATP diphosphohydrolase in heart, kidney, spleen, thymus, lung, skeletal muscle and brain. Signals for both ecto nucleotidases are very weak in liver. mRNAs for both proteins are present in PC12 cells, suggesting that the two nucleotidases may be co-expressed in the same neural cell. Using computer-aided sequence analysis, primary structure and membrane topography are compared with those of other members of the apyrase family. PMID- 9364475 TI - The role of cyclic AMP as a precursor of extracellular adenosine in the rat hippocampus. AB - Extracellular adenosine 3':5'-cyclic monophosphate (cAMP) is a potential source of the inhibitory neuromodulator adenosine in the brain. Previous work has demonstrated that cAMP, which is formed intracellularly, can be transported into the extracellular space and subsequently catabolized to adenosine. However, the physiological conditions under which cAMP release might lead to adenosine formation and activation of adenosine receptors are not well understood. In this study we demonstrate that superfusion of hippocampal slices with cAMP or forskolin led to the formation of extracellular adenosine which activated adenosine receptors in a manner comparable to that seen with adenosine superfusion. In contrast, application of brief pulses of cAMP onto the cell bodies of CA1 pyramidal neurons failed to produce an adenosine receptor-mediated response, while application of brief pulses of adenosine or AMP elicited significant responses. These data suggest that large, prolonged increases in extracellular cAMP levels can result in the formation of extracellular adenosine and the activation of adenosine receptors, but brief increases in cAMP levels in the vicinity of individual neurons cannot. These findings imply that increases in cAMP levels may lead to relatively slow increases in extracellular adenosine, as opposed to the fast, spatially restricted increases that would occur following the release of other adenine nucleotides. PMID- 9364476 TI - G protein coupling of the rat A1-adenosine receptor--partial purification of a protein which stabilizes the receptor-G protein association. AB - A membrane protein identified in cortical brain membranes and termed 'coupling cofactor', modulates G protein-coupling of the A1-adenosine receptor by reducing the catalytic efficiency of the receptor. Coupling cofactor traps the A1 adenosine receptor in the high affinity complex and, thus, is responsible for the resistance of high affinity A1-agonist binding to modulation by guanine nucleotides. In the present work, this effect was used for assaying the activity of coupling cofactor by reconstituting guanine-nucleotide resistant agonist binding to rat A1-adenosine receptors in detergent extracted brain membranes or in membranes from 293 cells after stable transfection with receptor cDNA. Coupling cofactor was partially purified from porcine brain membranes. The specific activity was modestly enriched (approximately 5-fold) after three chromatographic steps (DEAE-Sephacel, AcA34, MonoQ pH 8). Rechromatography of coupling cofactor over MonoQ at pH 7 resulted in a loss in specific activity if membranes of 293 cells but not if brain membranes were used as acceptor membranes. In addition, the molecular mass estimated by gel filtration decreased from > 150 kDa in the initial stage of purification to 40-30 kDa after this fourth chromatographic step. These two observations suggest that coupling cofactor requires an additional component that is present in brain membranes and is lost in later stages of purification. The activity of partially purified preparations of coupling cofactor activity relied also on the abundance of G protein alpha-subunits in the membrane. The activity on reconstitution with brain membranes or pertussis toxin pretreated 293 membranes was supported by addition of Gi alpha (rank order of protency: alpha i1 > alpha i3 > alpha i2) but not of G(o alpha). The selectivity for G protein alpha-subunits suggests that coupling cofactor may provide for an additional level of specificity in organizing receptor-G protein coupling. PMID- 9364477 TI - P2-receptor-mediated inhibition of serotonin release in the rat brain cortex. AB - The possibility of a P2-receptor-mediated modulation of the release of serotonin in the rat brain cortex was investigated in occipito-parietal slices preincubated with [3H]serotonin and then superfused and stimulated electrically (10 pulses, 1 Hz). Adenosine receptor agonists decreased the stimulation-evoked overflow of tritium at best slightly; the selective A1 agonist N6-cyclopentyl-adenosine caused no change. Several nucleotides had more marked effects: ATP (3-1000 microM), adenosine-5'-O-(3-thiotriphosphate) (3-300 microM) and P1,P5 di(adenosine-5')-pentaphosphate (3-300 microM) decreased the evoked overflow by up to ca 35%. AMP, alpha,beta-methylene-ATP and UTP produced smaller decreases and 2-methylthio-ATP and UMP caused no change. The inhibition by ATP was attenuated both by the P1-receptor antagonist 8-(p-sulphophenyl)-theophylline (100 microM) and by the P2-receptor antagonist suramin (300 microM) but was not changed by indomethacin (10 microM) and NG-nitro-L-arginine (10 microM). We conclude that the release of serotonin in the rat brain cortex is inhibited through presynaptic P1-receptors (which are not A1) as well as P2-receptors. Inhibition of release via P2-receptors has been previously shown for noradrenaline (brain cortex and hippocampus) and dopamine (neostriatum) and, hence, may be widespread. Differences between transmitter systems exist, however, in the degree of their sensitivity to presynaptic P2-receptor-mediated modulation. PMID- 9364478 TI - Immunohistochemical study of the P2X2 and P2X3 receptor subunits in rat and monkey sensory neurons and their central terminals. AB - Of the cloned P2X receptor subunits, six are expressed in sensory neurons, suggesting that the native channels may be heteromultimers with diverse composition. It has been proposed that P2X2 and P2X3 form heteromultimers in sensory neurons. We further tested this hypothesis by examining the relationship of P2X2 and P2X3 immunocytochemically. In rat dorsal root and nodose ganglia, P2X2- and P2X3-immunoreactivity (-ir) were highly colocalized, although single labeled cells were also present. In dorsal root ganglia (DRG), in some cases P2X2 ir appeared to be present in satellite cells. In dorsal horn of spinal cord, at low magnification the laminar localization of P2X2- and P2X3-ir overlapped, but at high magnification colocalization was rarely observed. In contrast, in the solitary tract and its nucleus (NTS), colocalization of P2X2- and P2X3-ir was seen at low and high magnification. These results suggest that the relationship of P2X2- and P2X3-ir is different in nodose and dorsal root ganglia and might reflect differences in the targeting of P2X receptors in different sensory neurons. In monkey, P2X2-ir was observed in DRG neurons and satellite cells and in dorsal horn of spinal cord. P2X3-ir was also seen in DRG neurons. However, the presence of P2X2-ir in NTS as well as the presence of P2X3-ir in spinal cord and NTS could not be established definitively. These results suggest species differences, although a more extensive study of primate sensory systems is necessary. PMID- 9364479 TI - Distribution of [35S]dATP alpha S binding sites in the adult rat neuraxis. AB - Highly abundant, saturable and specific binding sites for [35S]2'-deoxyadenosine 5'-O-(1-thio) triphosphate ([35S]dATP alpha S, Kd: 9 +/- 2 nM; Bmax: 39 +/- 8 pmol/mg protein) are present in adult rat brain membranes and have characteristics consistent with those expected for a P2Y1 receptor. The anatomical distribution of these binding sites in the brain and spinal cord was examined using in vitro autoradiography. The [35S]dATP alpha S binding sites showed a widespread distribution throughout the brain and spinal cord. They could be displaced by a large excess (100 microM) of 2-methylthioATP (2MeS-ATP) but not by uridine-5'-triphosphate (UTP) or alpha,beta-methyleneATP (alpha,beta-meATP). Within the cortical regions labelling was of equal medium density. However, discrete structures and nuclei within the olfactory bulb, subcortical telencephalon, hippocampal complex, thalamic regions and mesencephalon displayed a variety of densities. Within the spinal cord, gray matter was labelled at a greater density than the funiculi. The present study clarifies the anatomical distribution of P2Y1 and closely related receptors within the central nervous system of rat and extends the evidence that those receptors are abundant and widely distributed within the neuraxis. PMID- 9364480 TI - Properties of ATP receptor-mediated synaptic transmission in the rat medial habenula. AB - The properties of central ATP-mediated synaptic currents were studied using whole cell patch-clamp recording in rat medial habenula slices. Release was shown to be calcium dependent with a Hill coefficient of approximately 2. The voltage dependence of synaptic current amplitudes was approximately linear. Some reduction of the synaptic current amplitudes was observed at 10 mM extracellular calcium, suggesting calcium block/permeability of the channels. This was confirmed by observation of current-voltage reversal potentials in different calcium concentrations. We estimate that the channels underlying half the synapses showed a negligible calcium permeability. In the other four out of eight synapses the results suggest a very high calcium permeability with an estimated PCa/PCs of > 10. Thus, at -70 mV, in 1 mM calcium, more than 15% of the ATP mediated synaptic current is estimated to be carried by calcium, but only at synapses with calcium-permeable channels. Net current through these synaptic channels is also controlled by the voltage dependence of synaptic current decay time constants (increasing e-fold for 158 mV depolarization) and by a strong dependence of transmitter release on the frequency of stimulation of the presynaptic neurone, with failure rates increasing 3-fold as stimulation rates were increased from 1 to 10 Hz. PMID- 9364481 TI - Mechanically and ATP-induced currents of mouse outer hair cells are independent and differentially blocked by d-tubocurarine. AB - Mechano-electrical transducer channels (MET) and ATP-gated ion channels (P2X receptors) of hair cells have several properties in common: they share the same location at the apex of the cell, both channels are non-selective for cations and blocked by aminoglycosides and pyrazinecarboxamides (amiloride-related compounds). In this study, we test the relationship and possible identity of these two channel types. Using whole-cell patch-clamp recordings of outer hair cells (OHCs) of the cultured neonatal mouse cochlea and a fluid jet to stimulate their hair bundles mechanically, we show that d-tubocurarine, a blocker of P2X2 receptors, blocks MET channels with a half-blocking concentration of 2.3 microM. In contrast, the KD for the P2X2 receptors was 90 microM and 84 microM measured in hair cells and Xenopus oocytes, respectively. When hair bundles of OHCs were simultaneously stimulated with saturating mechanical stimuli and superfused by 100-300 microM ATP, transducer currents and ATP-activated currents were elicited simultaneously. Their amplitudes were additive, however. We conclude that MET- and ATP-activated currents are mediated by two distinct channel populations in hair cells. PMID- 9364482 TI - Tissue distribution of the P2X7 receptor. AB - The P2X7 receptor is a bifunctional molecule. The binding of ATP induces within milliseconds the opening of a channel selective for small cations, and within seconds a larger pore opens which allows permeation by molecules as large as propidium dyes (629 Da). In situ hybridization using a digoxigenin-labelled riboprobe, and immunohistochemistry using an antibody raised against a C-terminal peptide sequence, were used to determine the distribution of the P2X7 receptor mRNA and protein in rat and mouse tissues and cell lines. The brain of newborn rats showed a 6 kb RNA by Northern blotting, but this was not detectable in adult brain. By in situ hybridization and immunohistochemistry, there was heavy labelling of ependymal cells in both newborn and adult brain, but the brain parenchyma showed no labelling. However, P2X7 receptor-immunoreactive cells appeared in the penumbral region around an area of necrosis evoked by prior occlusion of the middle cerebral artery, suggesting expression of the receptor by activated microglia. NTW8 cells, a mouse microglial cell line, strongly expressed the P2X7 receptor mRNA and protein. The P2X7 receptor mRNA and protein were also observed in the majority of bone marrow cells, including those separately identified by their expression of other antigens as granulocytes, monocyte/macrophages and B lymphocytes. The expression of P2X7 receptor by brain macrophages rather than neurons would be consistent with a role in brain repair following inflammation, infarction or immune insult. PMID- 9364483 TI - Effects of divalent cations, protons and calmidazolium at the rat P2X7 receptor. AB - The P2X7 receptor is a uniquely bifunctional molecule through which ATP can open a small cationic channel typical of ionotropic receptors and also induce a large pore permeable to high molecular weight molecules (> 600 Da). Activation of this large pore can lead to cell lysis within 1-2 min. We asked whether pharmacological differences existed between the cationic channel and the cell permeabilizing pore by measuring whole-cell currents and uptake of a propidium dye (YO-PRO; Mw 629) in HEK293 cells stably expressing the rat P2X7 receptor, and comparing the actions of divalent cations and protons in these two assays. Currents in response to 2'-3'-(O)-(4-benzoyl benzoyl) ATP (BzATP, 30 microM) were inhibited by extracellular calcium, magnesium, zinc, copper and protons with half maximal inhibitory concentrations (IC50) of 2.9 mM, 0.5 mM, 11 microM, 0.5 microM and 0.4 microM, respectively. The inhibition was voltage independent in each case. YO-PRO uptake induced by BzATP was also inhibited with similar IC50 values. The rank order of potency of a range of divalents was Cu2+ > Cd2+ = Zn2+ > Ni2+ >> Mg2+ = Co2+ > Mn2+ > Ca2+ = Ba2+ >> Sr2+. These results suggest that these divalent cations and protons all act primarily as allosteric modulators to alter the affinity of ATP binding to the P2X7 receptor. In contrast, extracellular (but not intracellular) calmidazolium inhibited the BzATP-evoked current by up to 90% (IC50 = 15 nM) but had no effect on YO-PRO uptake. Thus, calmidazolium can block activation of the ionic channel but this does not prevent the formation of the large permeabilizing pore. PMID- 9364484 TI - ATP-mediated cytotoxicity in microglial cells. AB - Microglial cells are known to express purinergic receptors for extracellular ATP of both the P2Y and P2X subtypes. Functional studies have shown that both primary mouse microglial cells and the N9 and N13 microglial cell lines express the pore forming P2Z/P2X7 receptor. Here we identify the presence of this receptor in N9 and N13 cells with a specific polyclonal Ab and show that microglial cells expressing the P2Z/P2X7 receptor are exquisitively sensitive to ATP-mediated cytotoxicity while clones selected for the lack of this receptor are resistant. Transfection of HEK293 cells with P2X7 (but not P2X2) receptor cDNA confers susceptibility to ATP-mediated cytotoxicity. Morphological and biochemical analysis suggests that ATP-dependent cell death in microglial cells occurs by apoptosis. Finally, microglial cells release ATP via a non-lytic mechanism when activated by bacterial endotoxin, thus suggesting the operation of a purinergic autocrine/paracrine loop. PMID- 9364485 TI - Desensitization, recovery and Ca(2+)-dependent modulation of ATP-gated P2X receptors in nociceptors. AB - We have shown the presence and activity of ATP-gated ion channels (P2X receptors) in nociceptive nerve endings, supporting the theory that these channels mediate some forms of nociception [Cook S.P., Vulchanova L., Hargreaves K. M., Elde R. and McCleskey E. W. (1997) Distinct ATP receptors on pain-sensing and stretch sensing neurons. Nature 387, 505-508]. The kinetics and pharmacology of ATP-gated currents in nociceptors suggest that the channels are comprised of either homomeric or heteromeric combinations of P2X3 receptors. Consistent with the diverse nature of P2X structure, electrophysiological responses of rat tooth-pulp nociceptors fall into two distinct classes based on desensitization and recovery kinetics. Here, we quantified the dramatic differences in desensitization kinetics of transient and persistent currents. The major component of transient P2X current desensitized with a tau decay = 32 +/- 2 msec, while persistent current desensitized > 100-fold more slowly, tau decay = 4000 +/- 320 msec. Both currents recovered from desensitization in minutes: tau recovery = 4 min for transient current, and tau recovery = 0.7 +/- 0.2 min for persistent current. Persistent current recovery was often accompanied by a current "overrecovery" that averaged ca threefold magnitude prior to desensitization. Comparison of ATP current in elevated Ca2+ext also revealed differences in transient and presistent currents. In 2 mM Ca2+ext medium, decrease of Na+ext resulted in an almost complete reduction of persistent, but not transient, current. Subsequent elevation of Ca2+ext greatly increased the transient, but not persistent, current. Mechanistic explanations for either the increase in transient current magnitude by elevated Ca2+ext, or persistent current overrecovery may reflect endogenous pathways for P2X receptor modulation. PMID- 9364486 TI - Caffeine mimics the effect of a dopamine D2/3 receptor agonist on the expression of immediate early genes in globus pallidus. AB - In order to evaluate the effect of caffeine on striatopallidal neurons we used in situ hybridization to examine the mRNA expression of the immediate early genes (IEGs), c-fos, fos B, c-jun, jun B, NGFI-A and NGFI-B in globus pallidus in rats given single or repeated administration of caffeine. A significant induction of c fos mRNA, but not of any of the other IEGs, was found 2, 4 and 8 hr after a single injection of 50 mg/kg caffeine. Following repeated injections of caffeine for 2 weeks a single challenge with caffeine did not induce the expression of any of the studied genes. The ability of caffeine to increase pallidal c-fos mRNA expression was mimicked by the dopamine D2/3 receptor agonist quinpirole (1 or 3 mg/kg), whereas the dopamine D2/3 receptor antagonist raclopride (2 mg/kg) was ineffective. Caffeine and quinpirole did not have synergistic effects when given together. The caffeine-induced c-fos mRNA expression was not counteracted by concomitant treatment with raclopride. The present data provide evidence that acute treatment with caffeine reduces the activity of the striatopallidal neuron, and since this neuron is inhibitory the result is an increased activity in globus pallidus. The effect of blocking the striatal A2A receptors with caffeine is essentially identical to that observed after activation of dopamine D2 receptors, but is independent of these receptors. The fact that pallidal c-fos mRNA expression decreased upon repeated administration of caffeine may be related to the development of tolerance to locomotion stimulation that occurs following chronic caffeine ingestion. PMID- 9364487 TI - Down-regulation of adenosine A2A receptors upon NGF-induced differentiation of PC12 cells. AB - PC12 cell differentiation was induced by one week of nerve growth factor (NGF) treatment and adenosine A2A receptor expression and activity were analysed. Undifferentiated PC12 cells expressed very high levels of adenosine A2A receptors (approximately equal to 2 pmol/mg) and exhibited strong cyclic AMP (cAMP) responses when stimulated with the selective adenosine A2A receptor agonist 2-[p (2-carbonylethyl) phenylethylamino-5'-N-ethylcarboxamidoadenosine]. NGF-induced differentiation was accompanied by a down-regulation of adenosine A2A receptors: receptor binding decreased to 500 fmol/mg, immunoreactive A2A receptor protein was decreased by about half and cAMP production was reduced by 60%. In situ hybridization experiments demonstrated a heterogenous distribution of A2A receptor mRNA and a decreased number of strongly labelled cells after NGF treatment. Stimulation of the cells with the non-selective adenosine receptor agonist N-ethylcarboxamidoadenosine (NECA) inhibited NGF-induced mitogen activated protein kinase activation. These results thus show that NGF-induced differentiation of PC12 cells is accompanied by a decrease in A2A receptor mediated cAMP accumulation. This might be a way for PC12 cells to counteract an inhibitory effect of A2A receptor activation on some aspects of neurotrophin signalling. PMID- 9364488 TI - Neonatal cerebral hypoxia-ischemia: the effect of adenosine receptor antagonists. AB - The effects of nonselective (theophylline), A1-(DPCPX) or A2A-selective (SCH 58261) adenosine receptor antagonists administered before or after neonatal hypoxia-ischemia (HI) were studied on the extent of brain injury in 7-day-old rats evaluated after 14 days. A possible effect of theophylline (20 mg/kg) on expression of immediate early genes was studied with in situ hybridization. Theophylline (20, 30 or 60 mg/kg) given prior to HI reduced brain damage by 48% (P < 0.001), 36% (P < 0.01) and 34% (P < 0.05), respectively, compared to control rats. This effect was not explained by changes in temperature, cerebral blood flow, blood gas/acid base status or blood glucose during the insult. Theophylline enhanced the upregulation of c-fos and NFGI-A during reperfusion but did not prevent the decrease in adenosine A1 receptor mRNA. Posttreatment with SCH 58261 (0.2 or 2 mg/kg) reduced brain damage by 19% (P < 0.05) and 14% (NS), respectively, compared to control rats which was unrelated to the core temperature. DPCPX (2 or 10 mg/kg) had no effect on the development of brain injury. In conclusion, nonselective and A2A adenosine receptor antagonists reduced brain injury in a model of HI in immature animals. PMID- 9364489 TI - An event-related potential study of memory for words spoken aloud or heard. AB - Subjects made old/new recognition judgements to visually presented words, half of which had been encountered in a prior study phase. For each word judged old, subjects made a subsequent source judgement, indicating whether they had pronounced the word aloud at study (spoken words), or whether they had heard the word spoken to them (heard words). Event-related potentials (ERPs) were compared for three classes of test item; words correctly judged to be new (correct rejections), and spoken and heard words that were correctly assigned to source (spoken hit/hit and heard hit/hit response categories). Consistent with previous findings (Wilding, E. L. and Rugg, M. D., Brain, 1996, 119, 889-905), two temporally and topographically dissociable components, with parietal and frontal maxima respectively, differentiated the ERPs to the hit/hit and correct rejection response categories. In addition, there was some evidence that the frontally distributed component could be decomposed into two distinct components, only one of which differentiated the two classes of hit/hit ERPs. The findings suggest that at least three functionally and neurologically dissociable processes can contribute to successful recovery of source information. PMID- 9364490 TI - The role of the left mesial frontal cortex in fluent speech: evidence from a case of left supplementary motor area hemorrhage. AB - This study reports on a woman who suffered left anterior cerebral artery hemorrhage with a focal lesion undercutting the left supplementary motor area. After almost complete recovery of language the patient was left with dysfluent, halting speech. In a series of four experiments we examined the major factors influencing the patient's articulation. There was a significant effect of lexicality and syllabic length on repetition and articulatory learning (Experiments 1 and 2). The number of syllables was also found to influence, in a simple reaction task, onset latencies, but not inter-response times (Experiment 3). On the contrary, articulatory intricacy had no particular effect on either repetition or vocal reaction (Experiments 1 and 3). While repetition of real words was preserved, single word production in word generation tasks was impaired. Rhyme generation and alliteration, both of which rely on phonological processing, were particularly involved, whereas semantic word generation tasks like verb generation and generation of category members were relatively spared (Experiment 4). Control tasks revealed that the observed phonological processing deficit was confined to the condition of generating spoken language output. These experimental findings suggest that the patient's dysfluent speech could neither be attributed to a deficit of linguistic processing proper, nor to one of motor execution. Her speech disorder rather resulted from an impairment of initiating sequential articulations, particularly in association with the process of downloading temporarily stored multisyllabic strings from an articulatory buffer. This deficit could obviously be overcome in real word repetition through the use of a semantic lexical route. PMID- 9364491 TI - Modulations in cerebral hemodynamics under three response requirements while solving language-based problems: a transcranial Doppler study. AB - This experiment used transcranial Doppler ultrasound to measure blood flow velocity in the middle, anterior or posterior cerebral artery (MCA, ACA and PCA, respectively) while separate groups of college students (each n = 20) solved anagrams and constructed new words using letters of a target word, each while viewing, speaking or writing the responses. The silent viewing requirement affected global velocities only while constructing words: velocities in both the MCA and ACA were faster than in the PCA. Speaking the solutions during both types of problems yielded faster overall velocities in the MCA than in the PCA. Finally, writing the solutions while constructing words led to faster velocities in the MCA compared to both the ACA and PCA. Time-course patterns to velocity changes from the thinking periods showed elevations in MCA velocity at the beginning and end of the periods, while PCA velocity typically slowed below baseline in the middle of the periods. These data show that the kind of language based problem-solving task and the specific response requirement arranged to accomplish a task selectively affected velocity in three cerebral arteries. PMID- 9364493 TI - Unilateral and bilateral temperature comparisons in acallosal and split-brain subjects. AB - Therapeutic section of the corpus callosum in adult epileptic patients typically results in their incapacity to carry out interhemispheric comparisons of lateralized information. The fact that acallosal and early split-brain subjects display few of these symptoms when tested in the tactile modality has led to the suggestion that these patients may use ipsilateral projections of the somatosensory system more effectively. Compensation, however, is limited by the fact that the lemniscal pathway is strongly lateralized, especially for the distal parts of the body, where few ipsilaterally projecting fibres have been demonstrated. The pathway carrying temperature information has a larger ipsilateral component. Bilateral comparisons within the same hemisphere in subjects who are lacking the corpus callosum should be more common and the development of compensatory mechanisms in early-sectioned or acallosal subjects should be more likely. The objective of the present experiment was to evaluate differential thresholds for thermal stimuli applied on a number of regions either on the same side or on corresponding sites on opposite sides of the body. One subject callosotomized as an adult and one split-brain subject who underwent callosotomy in childhood, as well as three acallosal subjects, were compared to IQ-matched and normal-IQ control subjects. The fingers, forearm and trunk were tested. The comparison temperature was 30 degrees C and the other was varied in an ascending or descending fashion using a modified method of limits. Differential thresholds were similar for within- and between-side comparisons, and comparable to those of the IQ-matched subjects. The results indicate that comparisons involving temperature discrimination for stimuli applied to the two sides of the body do not require the integrity of the corpus callosum. PMID- 9364492 TI - Spatial extinction on double asynchronous stimulation. AB - Despite the fact that visual extinction is widely considered a space-based disturbance of selective attention, there has been little theoretical consensus about the nature of its pathogenic mechanism. A specific disruption in the ability to disengage attention from ipsilesional stimuli, or a loss of weight with which contralesional objects compete for visual selection, have been hypothesized to account for the disorder. We tested the merits of these two explanations in a right-hemisphere-lesioned patient, FB, who failed to recognize a contralesional target only when it was shown concurrently to an ipsilesional target (i.e. visual extinction). His task was to report two target letters presented in rapid succession to the left and right of the fixation point. The order of stimulus presentation (Left-First vs Right-First), and the intertarget interval (stimulus onset asynchrony) were varied systematically. We showed that contralesional extinction may occur for successively presented targets, not just for stimuli displayed at the same time. Of most importance, FB was seriously and equally impaired in dealing with a contralesional stimulus when this either preceded the ipsilesional stimulus or followed it by an interval less than about 600 msec. The data appear to contradict the disengagement hypothesis, which predicted a substantial reduction of extinction when a stimulus was displayed first into the lesioned side of space. We suggest that a competitive model of visual selective attention fits the data quite well. PMID- 9364494 TI - A restricted 'spotlight' of attention in visual object recognition. AB - We describe a patient (NJ), with a progressive visual disturbance, who showed an impairment in identifying larger visually-presented objects relative to their smaller counterparts. NJ showed this size effect for line drawings of objects, words and single letters. When presented with large letters comprised of smaller letters and asked to give speeded identification responses to either the large or small letters, NJ was grossly impaired at identifying the large letter. Additionally, when presented with a context meant to bias responding to either the large or small letter, NJ showed faster and more accurate responding in the small direction, but not in the large direction. We interpret these results as indicative of an impaired 'spotlight' of attention, which is deployed across the visual array, and is necessary for providing the selective visual attention responsible for the integration of visual features. PMID- 9364495 TI - The relationship between naming and semantic knowledge for different categories in dementia of Alzheimer's type. AB - We studied the relationship between naming and semantic memory in a group of 10 patients with dementia of Alzheimer's type. In an extension to a previous cross sectional study (Hodges, J. R. et al., Brain and Language, 1996, 54, 302-325), this relationship was investigated at two longitudinal points within each patient's cognitive decline. Two types of naming performance were compared: items that each patient named correctly at the first stage but failed to name at the second stage, as contrasted with items named correctly at both stages (thereby providing a control for cognitive decline in general). Semantic knowledge of the concepts represented by the pictures in the naming test was investigated at each stage using definitions to the spoken object name, scored particularly for the number of sensory and associative/functional features provided by the patient. At stage 2, an analysis of the definitions for named-->unnamed items as contrasted with named-->named objects revealed a significant loss of both sensory and associative information. A comparison between natural kinds (animals and birds) and artefacts (household objects, vehicles, etc.), however, demonstrated a striking interaction between category and type of information contained in the definitions. Specifically, stage 2 definitions of artefacts in the named- >unnamed set showed a disproportionate loss of associative/functional information, while definitions of animal names that patients failed to produce in response to the pictures were notably lacking in sensory features. This pattern supports the notion that successful naming relies on a subset of critical semantic features which vary somewhat across different categories of semantic knowledge. We suggest that these findings are best encompassed by a conception of semantic organization, Weighted Overlappingly Organized Features (WOOF), in which (i) knowledge about all objects is represented by a central, distributed network of features activated by both words and pictures, but (ii) natural kinds and artefacts are differentially weighted in favour of those features that are involved in learning about and experiencing different kinds of objects. PMID- 9364496 TI - The left parietal cortex and motor attention. AB - The posterior parietal cortex, particularly in the right hemisphere, is crucially important for covert orienting; lesions impair the ability to disengage the focus of covert orienting attention from one potential saccade target to another (Posner, M. I. et al., Journal of Neuroscience, 1984, 4, 1863-1874). We have developed a task where precues allow subjects to covertly prepare subsequent cued hand movements, as opposed to an orienting or eye movement. We refer to this process as motor attention to distinguish it from orienting attention. Nine subjects with lesions that included the left parietal cortex and nine subjects with lesions including the right parietal cortex were compared with control subjects on the task. The left hemisphere subjects showed the same ability as controls to engage attention to a movement when they were forewarned by a valid precue. The left hemisphere subjects, however, were impaired in their ability to disengage the focus of motor attention from one movement to another when the precue was incorrect. The results support the existence of two distinct attentional systems allied to the orienting and limb motor systems. Damage to either system causes analogous problems in disengaging from one orienting/movement target to another. The left parietal cortex, particularly the supramarginal gyrus, is associated with motor attention. All the left hemisphere subjects had ideomotor apraxia and had particular problems performing sequences of movements. We suggest that the well documented left hemisphere and apraxic impairment in movement sequencing is the consequence of a difficulty in shifting the focus of motor attention from one movement in a sequence to the next. PMID- 9364497 TI - Haptic processing by the left hemisphere in a split-brain patient. AB - We report the case of a patient who suffered an ischemic accident resulting in damage to the anterior part of the corpus callosum and to the white matter in the posterior right hemisphere. Recognition of two-dimensional haptic stimuli explored with the right hand was severely impaired. The deficit was not specific to the type of stimuli, since letters, digits and geometrical shapes were not correctly recognized. Poor performance was not due to a specific mode of haptic exploration, since deficits were also observed without active manipulation of the stimuli. In contrast, the patient correctly named visual letters presented in the right visual hemifield (left hemisphere), and recognized three-dimensional common objects palpated with the right hand. Comparable results were observed in a surgical split-brain patient tested as a control. We conclude that (i) the construction of spatial representations of haptic stimuli, such as two dimensional stimuli or three-dimensional block letters, cannot be fully realized in the intact left hemisphere, this ability requiring the contribution of both hemispheres, and (ii) tests for correct naming of common objects do not provide sufficient evidence to establish the integrity of the system involved in the identification of haptic information processed by the right hand of split-brain patients. PMID- 9364498 TI - Visual motion perception after brain damage: I. Deficits in global motion perception. AB - We report on the test results of a group of 32 mostly unilaterally brain-damaged patients examined for global visual motion perception. Three of these patients had severely impaired visual motion perception in their contralateral visual half field, a deficit remarkably similar to the perceptual defects found in V5 lesioned monkeys. Two of these three patients had a right-hemisphere lesion; the remaining one had a left-hemisphere lesion. We conclude that both hemispheres of the human brain contain an area, functionally equivalent to V5, which subserves visual motion perception in the contralateral visual half-field. Lesion analysis revealed that this area is located in the posterior medial temporal gyrus. PMID- 9364499 TI - Visual motion perception after brain damage: II. Deficits in form-from-motion perception. AB - We investigated form-from-motion perception (FFM perception) in a sample of 39 patients with acquired brain damage. Pronounced FFM deficits were found in two patients (FM1 and FM2) with biparietal lesions. Both patients were able to identify the relevant figure, when it was not embedded in obstructive texture. Moreover, they could localize the figures in the FFM condition, although they could not reliably identify them. The two patients had normal motion coherence thresholds. Their performance in a static figure-ground task did not differ from that of other patients. These findings imply that the FFM deficits are not caused by impairment of basic visual motion or form perception but are the consequence of damage to a parietal brain structure involved in the combined analysis of visual motion and form information. The nature and functional role of this brain structure as well as the implications of our results for models of FFM perception are discussed. PMID- 9364500 TI - Hemifield-specific visual recognition memory impairments in patients with unilateral temporal lobe removals. AB - Recent evidence on visual neglect suggests that each hemisphere maintains a retinotopically organized representation of the visual world contralateral to the current fixation point and that this representation is based not only on analysis of the current retinal input but, equally importantly, on information retrieved from memory. This idea predicts that unilateral damage to memory systems should produce a lateralized impairment of memory for the retinotopically contralateral visual world. To test this prediction we examined visual recognition memory performance in the left and right visual hemifields of patients who had undergone partial unilateral temporal lobe removals for the relief of epilepsy, either in the left hemisphere (n = 5) or the right (n = 5). The patients were given complex artificial scenes to remember, constructed of independent left and right halves, and were then tested for recognition of the left and the right halves separately. Stimuli were exposed tachistoscopically throughout and fixation was maintained on a central position. Patients made significantly more errors with half-scenes in the hemifield contralateral to their removal than in the ipsilateral hemifield, an increase of 50% in the error rate on average. The effect was seen equally in patients with left and right removals. This finding supports the idea that visual memory retrieval is retinotopically organized. PMID- 9364502 TI - Immunocytochemical expression of human muscle cell p75 neurotrophin receptor is down-regulated by cyclic adenosine 3',5'-monophosphate. AB - To investigate whether the immunocytochemical expression of low affinity neurotrophin receptor (p75) in human muscle is modulated by increased levels of intracellular cyclic adenosine 3',5'-monophosphate (cAMP), human cultured myogenic cells were treated with cAMP analogues dibutyryl cAMP (dbcAMP 0.5-1 mM) and 8-bromo cAMP (1 mM) or the adenylate cyclase activator forskolin (10-100 microM). Cultures were processed for indirect immunofluorescence microscopy using an anti-human p75 mAb. The treatment of cultured muscle cells with cAMP analogues or forskolin for two days induced a decrease of immunoreactivity for p75 and a reduction of both myotube formation and morphological cell differentiation. Removal of cAMP derivatives from the medium resulted in a return of immunoreactive cells to the levels of untreated controls. These data indicate that adenylate cyclase is involved in the regulation of human muscle p75. PMID- 9364501 TI - Gambiertoxin (CTX-4B), purified from wild Gambierdiscus toxicus dinoflagellates, induces Na(+)-dependent swelling of single frog myelinated axons and motor nerve terminals in situ. AB - The effects of gambiertoxin (CTX-4B), purified from the dinoflagellate Gambierdiscus toxicus, were assessed on the morphology of both frog myelinated axons and motor nerve terminals, using confocal laser scanning microscopy. During the action of the toxin (24 and 30 nM), a marked swelling of nodes of Ranvier and motor nerve terminals was observed. The CTX-4B-induced swelling could be prevented by blocking voltage-dependent Na+ channels with tetrodotoxin, and could be partly reversed by an external hyperosmotic solution containing 100 mM D mannitol. The results suggest that CTX-4B, by modifying voltage-dependent Na+ channels, increases internal Na+ concentration of axons and nerve terminals and consequently induces water influx to compensate such an increase. It is suggested that stimulated transmitter release by CTX-4B, as well as by hyperosmotic dmannitol, contribute also to the swelling of the terminals through an increase in their surface area. PMID- 9364503 TI - Ligand binding to porcine ionotropic glutamate receptors with chemically modified arginyl residues. AB - The involvement of arginyl residues in the binding of ligands to different ionotropic glutamate receptors, to the modulatory glycine site in the N-methyl-D aspartate (NMDA) receptor and to the NMDA-governed ionophore was assessed with porcine cortical synaptic membranes. The arginyl residues were covalently modified with phenylglyoxal. The binding and protection experiments showed that arginine residue(s) are directly involved in the binding of ligands to the agonist sites of all ionotropic glutamate receptors and to the modulatory glycine site but not to the ion channel in the NMDA receptor complex. PMID- 9364504 TI - Regulation of galanin in rat sympathetic neurons in vitro. AB - The neuropeptide galanin is induced in sensory and autonomic neurons after peripheral nerve lesion. Leukemia inhibitory factor (LIF) has been suggested to be involved in the up-regulation of galanin. A direct effect of LIF on galanin content in pure sympathetic neuron cultures dissociated from newborn rat superior cervical ganglia was investigated by radioimmunoassay and immunohistochemistry. Galanin increases in sympathetic neurons during a 12 day culture period in the presence of NGF (10 ng/ml). Five days after addition of LIF (10 ng/ml) a 7-fold elevation is observed when compared to control cultures. Furthermore, galanin increases significantly in the presence of non-neuronal cells and in response to potassium-induced depolarization. The proportion of galanin-immunoreactive neurons in mixed cultures is similar to that found in adult rat superior cervical ganglia after transection of the major postganglionic branches. The results corroborate the hypothesis that LIF, presumably released from ganglionic satellite cells, induces galanin in a subpopulation of sympathetic neurons in vivo and in vitro. PMID- 9364505 TI - Evaluation of dextromethorphan and dextrorphan as a preventive treatment of soman toxicity in mice. AB - Phencyclidine-like drugs are effective against convulsions and brain lesions related to soman intoxication but induce severe side effects. The well tolerated antitussive dextromethorphan (DM) and its metabolite dextrorphan (DX) have antiepileptic and neuroprotective properties that we evaluated in mice against 2 LD50 of soman in a three-drug pretreatment (atropine sulfate and oxime HI-6 plus DM: 20-50 mg/kg or DX: 10-40 mg/kg i.p). Neuroprotection was evaluated by measurement of hippocampal omega 3 binding site density. DM and DX have weak anticonvulsant and neuroprotective activities which are counterbalanced at high doses by an increased mortality due to respiratory distress for DM and by ataxia for DX. Thus DM and DX do not appear to be appropriate for the pretreatment of soman intoxication. PMID- 9364506 TI - Nociceptin-like immunoreactivity in autonomic nuclei of the rat spinal cord. AB - Immunohistochemical techniques were used to localize nociceptin-like immunoreactivity (NOCI-LI) in the rat spinal cords. NOCI-LI nerve fibers were distributed in three fairly well-define regions: superficial layers of the dorsal horn, central canal area, and intermediolateral cell column (ILp) of lower cervical, thoracic, upper lumbar, and sacral segments of the spinal cord. A few NOCI-LI somata of small diameter were noted in the dorsal horn; NOCI-LI cell bodies were infrequently observed in the ILp or ventral horn. Concentration of NOCI-LI in nerve fibers of the superficial layers and in fibers projecting into the spinal sympathetic and parasympathetic nuclei suggests that the peptide may participate in sensory as well as autonomic functions. PMID- 9364507 TI - Load compensation tasks evoke tremor in cerebellar patients: the possible role of long latency stretch reflexes. AB - 'Tremor' is one of the clinical signs of cerebellar dysfunction. Its nature remains subject to debate, one hypothesis being that of a predominant role of peripheral afferences in its genesis. This study was designed to study whether load compensating tasks, evoking sudden stretch, and thus stimulation of peripheral afferences induced tremor in cerebellar patients. We study the kinematics and EMG pattern of a load compensating task which consists of maintaining a constant elbow position despite the onset and cessation of a 2 Nm torque loading the elbow flexors in eight cerebellar patients and six controls. Angular position and velocity, and EMG of the biceps and triceps are recorded at a sampling rate of 1 kHz. In normal subjects, trajectories are simple with little overshoot of the aimed position. EMG analysis shows a long latency stretch response (LLSR) which initiates a phasic and then tonic voluntary activity. In cerebellar patients, the two prominent cinematic features are hypermetria and tremor. The stretch response is of the same latency, but the EMG pattern is modified with bursts of activity related to the tremor. These results show severe perturbations of load compensating tasks in cerebellar patients. We discuss the possible role of the exaggeration of LLSR in both hypermetria and tremor. PMID- 9364508 TI - Distribution of NADPH-d positive neurons during postnatal development of the rat somatosensory cortex correlates with gradients of neurogenesis and development. AB - The expression of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH d) was studied in the rat somatosensory cortex during postnatal development from day 6 to 120. Distribution of labeled neurons was quantified in dorso-medial and ventro-lateral aspects of the cortex, and correlated with known tridimensional gradients of histogenetic development and maturation of cortical neurons. NADPH positive neurons were non-pyramidal cells that in all developmental periods were more numerous in infragranular than in supragranular layers of the cortex. Additionally, more labeled cells were found in ventro-lateral than dorso-medial infragranular layers and in anterior than posterior aspects of the cerebral cortex. These patterns of distribution correlate well with the gradients of histogenetic development and with the pattern of maturation of cortical neurons. PMID- 9364510 TI - Experimental hypothyroidism increases immobility in rats in the forced swim paradigm. AB - Effects of severe and mild hypothyroidism on the immobile response to inescapable stress were examined in male Wistar rats using the forced swim paradigm. Rats were exposed to two sessions of inescapable swim stress: pretest (for 15 min) followed by test (for 5 min) 24 h later. Surgically thyroidectomized rats showed a significant increase (by 90%) in immobility during test compared to sham rats. Chronic administration of high (200 micrograms/kg per day) but not low (15 micrograms/kg per day) dose of T4 prevented the increase in immobility in thyroidectomized rats. Normal rats submitted to iodine-free diet for 2 weeks in order to produce a mild hypothyroidism showed a significant increase (by 60%) in immobility time during test compared to control rats. The results indicate that hypothyroid rats are more vulnerable to inescapable stress than normothyroid rats. PMID- 9364509 TI - Regulation of Na+ channel beta 1 and beta 2 subunit mRNA levels in cultured rat astrocytes. AB - Using quantitative competitive reverse transcription-polymerase chain reaction (RT-PCR), we found an increased level of Na+ channel beta 1 (Na beta 1) mRNAs in spinal cord astrocytes and in the B50 neuroblastoma cell line after exposure to 1 mM dibutyryl cAMP. In contrast, the calcium ionophore (1 microM A23187) did not affect Na beta 1 mRNA levels in these cells. Further, we amplified full length coding region of Na+ channel beta 2 (Na beta 2) mRNA from rat optic nerve and cultured astrocytes using RT-PCR. It appeared that the Na beta 2 mRNA level was increased by dibutyryl cAMP, but not by A23187, in spinal cord astrocytes. These findings suggest that the Na beta 1 and Na beta 2 mRNA levels in spinal cord astrocytes are influenced by increased cAMP but not by calcium. PMID- 9364511 TI - Chemical kindling induced by pentylenetetrazol changes cholecystokinin mRNA and peptide levels in rat frontal cortex. AB - Kindling model is useful to study the mechanism of learning and memory. Cholecystokinin (CCK) mRNA and CCK-like immunoreactivity (CCK-LI) levels in the hippocampus and frontal cortex of chemically kindled rats were determined at different time points. In the frontal cortex, chronic treatment with pentylenetetrazol (PTZ) (40 mg/kg per day for 8 days) increased CCK mRNA level at 7 days, and decreased CCK-LI level at 2 and 7 days after the last injection. However, neither CCK mRNA nor CCK-LI levels in the hippocampus changed. These results suggest that PTZ-induced kindling increases CCK mRNA expression and CCK LI release in the frontal cortex. PMID- 9364512 TI - Stimulatory effect of bombesin on phosphoinositide metabolism in the rat pineal gland. AB - The pineal gland is under complex peptidergic nervous control originating from hypothalamic nuclei. The daily rhythm of bombesin-like peptide in the hypothalamus suggests that this neuropeptide, similarly as other neuropeptides, might be involved in modulation of the physiological activity of the pineal gland. In our experiments we studied the mechanism of signal transduction of bombesin in the isolated pineal glands of rats. The phosphoinositide signalling system was examined by measuring 32P-labelling of phosphatidylinositol (PI), phosphatidylinositol phosphate (PIP) and phosphatidylinositol bisphosphate (PIP2), which reflects phosphoinositide cycle activation. Bombesin induced a significant increase in 32P-labelling of PI, PIP and PIP2. The antagonist of this neuropeptide, (D-Phe12-Leu14)-bombesin, suppressed the increase in 32P-labelling of all phosphoinositides. Bombesin was without effect on cAMP dependent protein phosphorylation. The data indicate that bombesin activates the PI signalling system via specific receptors. PMID- 9364513 TI - Thalidomide reduces MPTP-induced decrease in striatal dopamine levels in mice. AB - The effects of thalidomide, a sedative, anti-inflammatory and immunosuppressive agent were studied in the MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) murine model of Parkinson's disease. The striatal levels of dopamine (DA) and of its main metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were measured both in the MPTP control group (3 x 15 mg/kg intraperitoneally) and in the thalidomide groups (repeated treatments at 25 mg/kg or 50 mg/kg postoperatively). For mice treated with thalidomide, a dose-dependent protection was observed against the MPTP-induced decrease in DA. The decrease in HVA levels was totally antagonized by thalidomide at both doses. That thalidomide has activity in this model suggests that an inflammatory process may be involved in the induction of lesions by MPTP in DAergic neurons. PMID- 9364514 TI - p27/kip1 expression in human astrocytic gliomas. AB - In the cell cycle, p27/kip1 acts as an inhibitory protein of cyclin-cdk complexes. p27/kip1 immunohistochemistry was performed in 50 gliomas (15 astrocytomas, 15 anaplastic astrocytomas and 20 glioblastomas) by a polyclonal antiserum. In the same tumours, proliferation marker Ki-67 was studied by MIB-1 antibody. For both, a labelling index (LI) was calculated after counting at least 1000 cells at x1000 magnification. p27 is diffusely and strongly expressed in astrocytomas (LI mean = 44.4%), whereas positive nuclei decrease in number and in staining intensity in anaplastic astrocytomas (LI mean = 5.86%) and glioblastomas (LI mean = 2.1%). An inverse correlation has been found between MIB-1 LI and p27 LI calculated in the same areas. Interestingly, in malignant gliomas the absence of p27 was independent from any histological feature of differentiation or anaplasia. p27 expression is thus reduced in malignant gliomas as in other malignancies. Since mutations of p27/kip1 are extremely rare, posttranslational changes are hypothesised also in astrocytic gliomas. PMID- 9364515 TI - Somatotopic source arrangement of 600 Hz oscillatory magnetic fields at the human primary somatosensory hand cortex. AB - Based on low-noise superconducting quantum interference devices (SQUIDs) magnetoencephalography allows the non-invasive detection of low-amplitude high frequency brain responses evoked about 20 ms after electric hand nerve stimulation. The main spectral energy of these brief oscillatory bursts (near 600 Hz) is in the range typical for rapidly repeated action potentials. Here, the magnetic fields of median and ulnar nerve evoked 600 Hz bursts are shown to exhibit a somatotopic arrangement at the primary somatosensory hand cortex closely resembling that of the concomitant postsynaptic primary cortical response (?N20m'). Two possible burst generators are discussed: (1) repetitive spike volleys conducted along the terminal segments of somatotopically arranged thalamocortical axons, and (2) early intracortical spike activity in nerve specific subterritories of the 3b hand area. PMID- 9364516 TI - Blockers of NMDA receptor restore paired-pulse inhibition in the rat dentate gyrus lesioned by perforant path stimulation. AB - The ?dormant basket cell' hypothesis postulates, that after status epilepticus, inhibitory interneurons in the hippocampus are deafferented from their excitatory inputs. We provide evidence for active suppression of hippocampal inhibition. Status epilepticus-like perforant path stimulation induced loss of interneurons and loss of inhibition in the rat dentate gyrus. This loss was transiently reversed by antagonists acting at three different sites of the N-methyl-d aspartate (NMDA) receptor. Intrahippocampal administration of gamma-aminobutyric acid (GABA) agonists, which were expected to increase inhibition, resulted in the opposite effect. Although the substrate for the observed effects of pharmacological agents cannot be certainly confined to the ?dormant' basket cell, they suggest the expression of hippocampal circuits that actively suppress inhibition through an NMDA synapse. PMID- 9364517 TI - Low level expression of calcium-sensor protein VILIP induces cAMP-dependent differentiation in rat C6 glioma cells. AB - Wild-type visinin-like-protein (VILIP) and a myristoylation-deficient VILIP mutant, when stably expressed at low levels in C6 cells, enhances or reduces the basal cAMP-level, respectively. The morphology of wild-type VILIP-transfected cells resembles that of differentiated astrocytes, whereas the myristoylation mutant shows a phenotype similar to parental cells, but with reduced cell growth. In both parental and myristoylation mutant cells a differentiated phenotype similar to that produced by wild-type VILIP-transfected cells is inducible with 8 bromo-cAMP. The changed morphology parallels an increase in the expression of the astrocytic differentiation marker glial fibrillary acidic protein (GFAP) in wild type VILIP-transfected and cAMP-differentiated cells, but a decrease of GFAP in myristoylation mutant cells. These results suggest that depending on myristoylation, low level ectopic expression of VILIP affects basal cAMP homeostasis differentially, thereby influencing differentiation of C6 model cells. PMID- 9364518 TI - Generalised seizure-induced changes in rat hippocampal glutamate but not GABA release are potentiated by repeated seizures. AB - The effects of repeated or a single generalised seizure on extracellular glutamate and gamma-aminobutyric acid (GABA) levels in the ventral hippocampus of the freely-moving rat were studied using maximal electroshock-induced seizures in conjunction with in vivo microdialysis. A single seizure resulted in three phases of post-ictal changes in glutamate and GABA levels: during phase I, there were transient increases in both glutamate and GABA whilst in phase II, levels of both amino acids were reduced. In phase III, glutamate levels were elevated above basal whilst the decrease in GABA levels was sustained. Following repeated seizures, the phase I rise in glutamate was increased 3-fold and the phase III rise was significantly potentiated, compared with the changes produced by a single seizure. No differences were observed in the post-ictal changes in GABA levels between a single or repeated seizures. PMID- 9364519 TI - The regional pattern of D4 gene expression in human brain. AB - Using a competitive reverse transcription-polymerase chain reaction (RT-PCR) assay levels of D4 gene expression have been determined in 16 regions obtained from a single control brain. Relatively high levels of expression were detected in the prefrontal and temporolimbic structures whilst low levels were detected in striatal regions. This pattern correlates with the reported distribution of the D4 receptor. PMID- 9364520 TI - Cognitive operations in the human caudate nucleus. AB - We have addressed the role of the head of caudate nucleus in taks of lexical decision, semantic categorization, reading aloud, memory retrieval and object naming by recording neuronal activity from depth electrodes in parkinsonism patients. The firing rate of cells was increased within 400-600 ms when semantic processing was required. Phonological differences increased firing from 1000 to 1200 ms. These responses were similar to those described earlier in Broca's area. Both reading aloud and explicit memory retrieval tasks elicited an inhibition in firing of the same cells with an onset around 800 ms. The results confirm earlier lesion and stimulation studies, and provide a basis for relating cellular activity to studies of blood flow and scalp electrical activity in similar cognitive tasks thus helping us to understanding the cellular mechanisms involved in human cognition. PMID- 9364521 TI - Dynamic palmitoylation of neuromodulin (GAP-43) in cultured rat cerebellar neurons and mouse N1E-115 cells. AB - We conducted pulse-chase and metabolic labeling experiments to determine directly whether palmitoylation of neuromodulin in neurons is dynamic, and if acylation is regulated. The rates of turnover of neuromodulin protein and associated palmitoyl groups were quantified using cultured cerebellar granule neurons and the neuronal cell line N1E-115. The half-life of [3H]palmitate bound to neuromodulin was approximately 5 h, whereas the half-life of the [35S]methionine-labeled neuromodulin was greater than 50 h. Metabolic and pulse-chase labeling experiments were carried out in the presence of various activators of cellular signaling pathways. Our data indicate that dynamic acylation and deacylation of neuromodulin in neurons are constitutive and are not regulated by G protein activation or other signals that control growth cone dynamics. PMID- 9364523 TI - The in vivo effect of lipopolysaccharide on Na+,K(+)-ATPase catalytic (alpha) subunit isoforms in rat sciatic nerve. AB - The Na+,K(+)-ATPase catalytic (alpha) subunit in sciatic nerve of lipopolysaccharide (endotoxin, LPS)-treated rat was investigated. Using Western blot to determine subunit isoform polypeptide levels in rat sciatic nerve, we found a substantial reduction in alpha 1 polypeptide, but not that of alpha 2 and alpha 3 polypeptides, after the administration of LPS. Moreover, when rats were treated with polymyxin B (a LPS neutralizer) and NG-nitro-L-arginine (an inhibitor of nitric oxide (NO) synthase), the effects of LPS were reversed. These results implicate a specific marked deficit in alpha 1 subunit isoform of Na+,K(+)-ATPase in the pathogenesis of neuropathy during endotoxemia, through, at least in part, the L-arginine/NO pathway. PMID- 9364522 TI - Developmental changes in integrin beta-subunits in rat cerebral cortex. AB - The present study was carried out to characterize the developmental expression of beta 1-, beta 5- and beta 6-integrin subunits in rat cerebral cortex. Using reverse transcriptase-polymerase chain reaction, mRNA of the three beta-subunits were shown to be present at all developmental stages. Based on immunoblots, beta 1-subunit expression was decreased during cortical development from embryonic stages to adults. beta 6-subunit expression appeared only in adult cortex. beta 5 subunit expression did not change during development. These beta-subunits were expressed in cortical embryonic cells as revealed by immunological studies in vitro. beta 5 and beta 6 were also present in neuronal cells and in oligodendrocytes in adult cortex. Altogether, these results demonstrate that rat cerebral cortex expresses distinct integrin beta-subunits with different developmental profiles. This switch of beta-subunits may be an important mechanism for the regulation of cell behaviour during development. PMID- 9364524 TI - [Recent progress in cancer diagnosis and treatment]. PMID- 9364525 TI - [Progress in diagnostic imaging of the bone and soft tissue tumors]. PMID- 9364526 TI - [Treatment for coxarthrosis]. PMID- 9364527 TI - Renewing the commitment to collaboration: an imperative. PMID- 9364528 TI - Futures research methods. PMID- 9364529 TI - Patients' attitudes toward advance directives and end-of-life treatment decisions. AB - Much of the patient education about advance directives described in the literature involves explaining the purpose of advance directives to patients and guiding them through the process of issuing a directive. However, well over half of the subjects in this study claimed to know enough about the directives to issue one, and almost all subjects expressed a preference for issuing directives when healthy. Although health care agencies that wish to adhere to the PSDA must continue to ask all patients if they have issued an advance directive, aggressive patient education programs that press hospitalized patients to consider issuing an advance directive may be perceived by patients as coercive and uncaring. Patient education may be more likely to achieve the goals of the PSDA if it is provided before hospitalization and if patients are encouraged to discuss their care preferences with family members who would be in a position to speak for them at the end of life. Further study of the few patients who choose to issue an advance directive would be informative. When and why they chose to issue the directive should be explored. Patients who report issuing an advance directive but do not provide their physician or hospital with a copy of the directive upon admission should also be studied to determine if this represents a desire not to activate the directive during the current admission or simply confusion about the disposition of this document. Finally, most studies of advance directives have been cross-sectional. Longitudinal study of patients who issue advance directives are needed to determine the effectiveness of these documents in influencing the end-of-life treatment that patients receive. PMID- 9364531 TI - The National Institute of Nursing Research explores opportunities in genetics research. PMID- 9364530 TI - Assisted suicide: implications for nurses and nursing. AB - Assisted suicide is an issue of great importance to nurses. This issue reflects our values and beliefs as a society, calls for a clear and precise response as a profession, and challenges individual nurses to think about their own moral views. The history of the debate and the compelling moral arguments on both sides attest to the complexity of the issue and also suggest that it will not soon be resolved. The current position of the profession, as expressed in the ANA Code for Nurses and a specific position statement, were reviewed. The dilemma faced by the individual nurse who perceives an obligation to adhere to the guidelines specified by his or her profession's code and yet whose conscience dictates an act in violation of this code has been discussed as an instance of conscientious objection. While this analysis has been necessarily brief, it was intended to illustrate the importance of being clear about one's personal moral views and equally clear about one's duty to fulfil the obligations stemming from the profession's public statements. It is essential that the profession continue to explore the moral issues involved in requests for assistance in dying and provide additional guidelines for practicing nurses, with sound rationale for the profession's position. PMID- 9364532 TI - Revisioning, re-educating, regenerating, and recommitting nursing for the twenty first century. PMID- 9364533 TI - Factors limiting evaluation of health care programs for the homeless. AB - The problem of homelessness and the need for health care by homeless people does not seem to be subsiding. All indications are that current legislation to implement dramatic welfare reform will eventually increase the number of homeless persons. Evaluation to guide, monitor, and select the most effective approaches in the provision of health care will remain a key element in health care delivery. Although barriers regarding evaluation of homeless health care have been reported by previous researchers as similar, the results in this study document findings elicited from administrators in the field. The administrators have the expertise to address some of the more common barriers and reduce them. Ways to approach this endeavor and to support staff in participating in and successfully integrating evaluation activities into health care provision will require attention of funding agencies, program administrators, and inclusion of staff and clients in planning. As the era of managed care becomes the focus of how health care is delivered, evaluation of existing programs will be essential to their survival. The descriptive information obtained in this exploratory study provides useful instruction for considering issues that need to be addressed in planning and implementing evaluation of health care to homeless persons. PMID- 9364534 TI - Nurses' perceptions of consensus reports containing recommendations for practice. PMID- 9364535 TI - Docetaxel: today's results and tomorrow's promises. PMID- 9364536 TI - Docetaxel as neoadjuvant chemotherapy in patients with stage III breast cancer. AB - Optimal management of locally advanced breast cancer (stage III) generally includes a combination of primary chemotherapy followed by surgery (if feasible), and local radiotherapy and adjuvant chemotherapy with or without hormonal therapy. An ongoing phase II study is being performed to evaluate the use of 4 cycles of 100 mg/m2 of docetaxel (Taxotere) administered as a 1-hour intravenous infusion once every 3 weeks followed by surgery, 4 cycles of standard-dose doxorubicin/cyclophosphamide (Cytoxan, Neosar) chemotherapy, and radiation, with and without tamoxifen (Nolvadex) in patients with locally advanced breast cancer. Preliminary results from 33 patients included in this phase II study are reported here. A partial response was achieved in 22 patients (67%), with 6 patients (18%) experiencing a complete response with this regimen. One patient with a complete response was confirmed to have a complete pathologic response at the time of surgery. Febrile neutropenia was noted in 8 patients (24%) and in 8 of the 120 treatment cycles (7%) administered. Future trials aimed at increasing the number of pathologic complete responses in patients with stage III breast cancer may require the use of docetaxel in combination with other active agents or the use of dose-dense scheduling schemes. PMID- 9364537 TI - Docetaxel vs doxorubicin in metastatic breast cancer resistant to alkylating chemotherapy. AB - Single-agent docetaxel (Taxotere) has been shown to be highly active in metastatic breast cancer, with an overall response rate of 47%, median time to progression of 4 months, and survival of 10 months when administered as second line therapy. These data compare favorably with those reported for doxorubicin (Adriamycin), which has been considered the most active single agent in this setting. This nonblinded, multicenter, randomized phase III study compared the median time to progression, response rate, quality of life, toxicity, and survival after treatment with docetaxel or doxorubicin in patients with metastatic breast cancer in whom previous alkylating chemotherapy failed. Patients were randomized to receive an intravenous infusion of either docetaxel, 100 mg/m2, for 1 hour once every 3 weeks or doxorubicin, 75 mg/m2, for 15 to 20 minutes once every 3 weeks. This preliminary analysis presents data on 200 of 326 patients recruited. It was performed after the completion of patient accrual. The median time to progression was greater in the docetaxel group than in the doxorubicin group (29 vs 21 weeks, respectively; P = not significant). Overall response rates were higher with docetaxel (47% vs 27%), and fewer patients in the docetaxel group had progressive disease as their best overall response (10% vs 22%). Both regimens caused the same incidence and severity of neutropenia, yet patients treated with doxorubicin had a higher incidence of infection and febrile neutropenia. In addition, doxorubicin produced a higher incidence of grade 3 to 4 thrombocytopenia. Cardiac toxicity led to discontinuation in 7 patients and death in 2 patients in the doxorubicin group; fluid retention led to discontinuation in 1 patient in the docetaxel group. Based on this preliminary analysis, docetaxel was more active and safer than doxorubicin in patients with metastatic breast cancer in whom previous alkylating chemotherapy failed. PMID- 9364539 TI - Review of docetaxel/doxorubicin combination in metastatic breast cancer. AB - Docetaxel (Taxotere) and doxorubicin (Adriamycin) have each demonstrated significant activity in metastatic breast cancer. Thus, the combination of docetaxel and doxorubicin has been evaluated in phase I trials to establish the dose-limiting toxicity, maximum tolerated dose, recommended dose for future phase II and III studies, and toxicity profile of the two agents used in combination. Results from phase I trials in patients with metastatic breast cancer indicate that the docetaxel/doxorubicin combination is well tolerated. The recommended dose for the combination regimen is either 50 mg/m2 of doxorubicin followed by 75 mg/m2 of docetaxel or 60 mg/m2 of both drugs, without granulocyte colony stimulating factor (G-CSF) support. Febrile neutropenia complicated by grade 3 infection was the dose-limiting effect at the maximum tolerated dose. The response rate at this dose level was 90%. Based on the preliminary results of phase I studies, further phase II and III studies of a docetaxel/doxorubicin combination regimen are warranted. PMID- 9364538 TI - Docetaxel vs mitomycin plus vinblastine in anthracycline-resistant metastatic breast cancer. AB - This nonblinded, multicenter, randomized phase III study compares the median time to progression (primary endpoint), response rate, and quality of life, safety, and survival of docetaxel (Taxotere) vs mitomycin (Mutamycin) plus vinblastine (Velban) in patients with metastatic breast cancer in whom previous anthracycline containing chemotherapy has failed. Patients were randomized to receive an intravenous infusion of either 100 mg/m2 of docetaxel for 1 hour every 3 weeks, or 12 mg/m2 of mitomycin every 6 weeks plus 6 mg/m2 of vinblastine every 3 weeks. This preliminary analysis presents data on 200 patients among 392 patients recruited. Median time to progression was longer in the group treated with docetaxel compared with the mitomycin/vinblastine group (17 vs 9 weeks). The overall response rates were higher with docetaxel (28% vs 13%, respectively), and fewer patients in the docetaxel group had progressive disease as their best overall response (29% vs 48%). As expected, thrombocytopenia was more common in the mitomycin/vinblastine group, and neutropenia occurred more frequently in the docetaxel group. Severe fluid retention in the docetaxel group (8.7%) resulted in treatment discontinuation in 5 patients (5%). Severe thrombocytopenia (12%) and constipation (6%) led to treatment discontinuation in 7 and 3 patients, respectively, in the mitomycin/vinblastine group. Based on this preliminary analysis, docetaxel appears to be equally as safe as and more active than mitomycin/ vinblastine in patients with metastatic breast cancer in whom previous anthracycline-containing chemotherapy has failed. These results are subject to cautious interpretation because this analysis was conducted on the first 200 patients who finished the study treatments, and these preliminary results may underestimate response and overstate treatment discontinuation rates. Thus, the final analysis on the entire patient population is necessary to confirm these preliminary findings. PMID- 9364540 TI - Combination docetaxel/cyclophosphamide in patients with advanced solid tumors. AB - Preclinical studies show that docetaxel (Taxotere) and cyclophosphamide (Cytoxan, Neosar) are synergistic against MA 13/C mammary adenocarcinoma. Both agents are highly active as monotherapy in a number of tumors, including metastatic breast cancer. Therefore, we performed a phase I dose-finding study to determine the maximum tolerated dose of this combination regimen in patients with advanced solid tumors. A total of 45 patients were enrolled and received cyclophosphamide followed by docetaxel, both administered as 1-hour intravenous infusions once every 3 weeks. The dose levels of cyclophosphamide/docetaxel were 600/60 mg/m2 (group 0), 600/75 mg/m2 (group I), 700/75 mg/m2 (group 2), 800/75 mg/m2 (group 3), 800/85 mg/m2 (group 4), 800/75 mg/m2 (group 5), and 800/85 mg/m2 (group 6). Patients with dose-limiting neutropenia in groups 5 and 6 received 300 micrograms of granulocyte colony-stimulating factor (G-CSF) (filgrastim [Neupogen]) support on days 2 through 9 during subsequent cycles of chemotherapy. All patients received premedication with 8 mg of dexamethasone twice daily for 5 days, beginning 1 day prior to chemotherapy. The dose-limiting toxicity was neutropenia fever. The recommended dose for phase II studies of cyclophosphamide/docetaxel is 700/75 mg/m2 in previously treated patients and 800/75 mg/m2 in previously untreated patients. G-CSF support did not allow for further dose escalation. Preliminary results from this phase I trial indicate that the combination of docetaxel and cyclophosphamide produced an objective response rate of 69% in 32 patients with metastatic breast cancer (including 3 patients who achieved complete responses). PMID- 9364541 TI - Docetaxel/doxorubicin/cyclophosphamide in the treatment of metastatic breast cancer. AB - Preliminary results from phase I trials suggest that the use of docetaxel (Taxotere) and doxorubicin (Adriamycin) is a well tolerated and highly active combination regimen for patients with metastatic breast cancer. The maximum tolerated dose of this combination was 50 mg/m2 of doxorubicin given as an intravenous bolus followed 1 hour later with 75 mg/m2 of docetaxel given as a 1 hour intravenous infusion. Because cardiotoxicity was not observed with this combination, we added cyclophosphamide (Cytoxan, Neosar) in a phase II trial to determine the antitumor activity and tolerability of this 3-drug combination as first-line therapy in patients with metastatic breast cancer. Preliminary results from this study indicate that the Taxotere/ Adriamycin/Cyclophosphamide (TAC) combination produces response rates of up to 80%. However, frequent grade 4 neutropenia was seen in 68% of cycles, febrile neutropenia in 5.5% of cycles, and grade 3 to 4 infection in .8% of cycles. Cardiac toxicity was rare, with 1 case of reversible congestive heart failure (2%), which occurred 2 months after completion of chemotherapy. These preliminary data show that TAC is highly active and that docetaxel did not significantly increase the cardiotoxicity of doxorubicin. Phase III studies in both the first-line and adjuvant settings are warranted. PMID- 9364542 TI - Docetaxel in combination with platinums in patients with advanced non-small-cell lung cancer. AB - Docetaxel (Taxotere) is a semisynthetic taxoid that possesses significant activity as a single agent in the treatment of patients with non-small-cell lung cancer. In previously untreated patients with non-small-cell lung cancer, 100 mg/m2 of docetaxel administered as an intravenous infusion over 1 hour once every 3 weeks produced response rates that ranged from 21% to 38% and median survivals of 25.2 to 47.0 weeks. In patients with advanced non-small-cell lung cancer who had previously failed cisplatin (Platinol)-based chemotherapy, docetaxel produced median response rates of 20% to 21% and median survival of 28 to 42 weeks. This review summarizes results from key phase I and II studies demonstrating the antitumor activity and tolerability of docetaxel combined with platinum compounds for patients with advanced non-small-cell lung cancer. Phase I trials determined that 75 mg/m2 of docetaxel and 75 mg/m2 of cisplatin is the recommended dose for phase II and III trials. Overall, response rates with docetaxel and cisplatin have ranged from 21% to 48% and median survival of 8 to 13 months has been achieved in phase II trials. Regarding docetaxel and carboplatin, results from phase I trials in patients with nonhematologic solid tumors indicate that this combination is well tolerated. The maximum tolerated dose of docetaxel in combination with carboplatin (target area under the time-concentration curve of 6 mg/mL.min) is 90 mg/m2 without granulocyte-colony stimulating factor (G-CSF) (filgrastim [Neupogen]) support and 100 mg/m2 with G-CSF support. The combination of docetaxel and carboplatin is presently being evaluated in a multicenter phase II study for patients with advanced non-small-cell lung cancer. PMID- 9364543 TI - Combination docetaxel/vinorelbine for metastatic breast cancer and non-small-cell lung cancer. AB - Docetaxel (Taxotere) and vinorelbine (Navelbine) have both demonstrated activity as single agents for the treatment of patients with metastatic breast cancer and non-small-cell lung cancer. With 100 mg/m2 of docetaxel administered as a 1-hour intravenous infusion once every 3 weeks, projected median survival in previously untreated and treated patients with non-small-cell lung cancer is reported to be approximately 9 months. In addition, response rates have ranged from 23% to 36% and 17% to 21% in these respective patient populations. Preliminary studies indicate that in previously untreated patients with non-small-cell lung cancer, vinorelbine provides a survival benefit that is greater than best supportive care and similar to that of platinum-based chemotherapeutic regimens. Investigation into the use of these agents in combination is supported by synergy shown in preclinical models, nonoverlapping side-effect profiles, and the schedule independence of docetaxel. Preliminary results from phase I and II combination studies are encouraging, and no neurotoxicity has been observed. Based on these data, further study into the combined use of docetaxel and vinorelbine in patients with non-small-cell lung cancer is warranted. PMID- 9364544 TI - Docetaxel in combination with fluorouracil for advanced solid tumors. AB - The results from preclinical studies using murine tumor models show that the combination of docetaxel (Taxotere) and fluorouracil (5-FU) is highly synergistic. Phase I studies in patients with advanced solid tumors indicate that 60 mg/m2 of docetaxel administered as a 1-hour intravenous infusion followed by a daily intravenous bolus of 300 mg/m2 of 5-FU on days 1 through 5 is the recommended dose for phase II studies. Preliminary results from another phase I study using a continuous infusion regimen for 5-FU suggest that 85 mg/m2 of docetaxel administered as a 1-hour intravenous infusion followed by continuous infusion of 750 mg/m2 per day of 5-FU on days 1 through 5 may be the recommended dose for phase II studies. As expected, dose-limiting toxicities included neutropenia and mucositis. Ongoing phase I/II and II studies are investigating the combination of docetaxel with continuous infusion of 5-FU in patients with metastatic breast cancer and with cisplatin (Platinol) and continuous infusion of 5-FU, with and without leucovorin, in patients with head and neck cancer. Preliminary results are encouraging and warrant further study. PMID- 9364545 TI - Two modes of auditory hair cell loss following acoustic overstimulation in the avian inner ear. AB - To determine the type of cell death occurring and how the removal of damaged cells proceeds following overstimulation, we examined chick basilar papillae using an in situ DNA nick end labeling method and transmission electron microscopy. Two distinct modes of hair cell loss were identified. First, hair cells which had not progressed into typical cell death processes, apoptosis or necrosis, were deleted by extrusion from the epithelium just after sound exposure. Second, hair cells manifested degeneration through the process of apoptosis, then further deterioration within the epithelium after the beginning of the process of hair cell regeneration. The latter mode may contribute to the following repair processes. PMID- 9364547 TI - Immunoelectron-microscopic localization of synaptophysin in the organ of Corti of the guinea pig. AB - Synaptophysin has been localized previously in the mammalian cochlea at the light microscopic level and in few reports by electron microscopy using either a preincubation procedure or the avidin-biotin reaction. Here we present results of the electron-microscopic analysis for postembedding immunoreactivity of synaptophysin in the cochlea of the guinea pig of LR-White-embedded samples. Strong synaptophysin immunoreactivity is located in the cytoplasm of the efferent nerve endings at the base of inner and outer hair cells. Besides this, some antibodies to synaptophysin were also identified in the cytoplasm of outer hair cells. To get more information about the cellular content of synaptophysin, the density of the immunoreaction per square micrometer was determined for the outer hair cells of the second turn of the cochlea counting the gold particles in numerous ultrathin sections. The role of synaptophysin identified in the cytoplasm of outer hair cells is discussed. PMID- 9364546 TI - Localization of nitric oxide synthase isoforms (I, II and III) in the endolymphatic sac of the guinea pig. AB - The localization of nitric oxide (NO) synthase (NOS) isoforms was examined in the endolymphatic sac (ES) of the pigmented guinea pig by indirect immunohistochemistry. The cytoplasm of the epithelial cells in the ES showed both NOS-I and -III immunoreactivity, whereas their nuclei appeared negative. NOS-III staining was also observed in the endothelial lining of the blood vessels. These findings support the hypothesis that NO in the epithelial cells may play an important role for the active intracellular transport of the endolymph and ion. NO may also be crucially involved in the regulation of ES blood flow. Immunostaining for NOS II revealed no reactivity in general, while in lipopolysaccharide-inoculated animals, intense reactivity was found in the cytoplasm of the ES epithelial cells as well as macrophages in the lumen. Thus it has been indicated that NO also may play an important role in the immunodefensive mechanisms in the ES. PMID- 9364548 TI - Measurement of [Ca2+]i and [Na+]i in outer hair cells isolated from gerbil cochlea. AB - Outer hair cells (OHCs) become sodium- and calcium-overloaded after being isolated in high-sodium medium. Most of the sodium and calcium leak occurs through 10-15% of the transduction channels that are open at the resting position of the hair bundle. However, [Ca2+]i and [Na+]i in OHCs can vary greatly from cell to cell even though they all appear normal. Different [Ca2+]i and [Na+]i may result from different leak conductance through the transduction channels. The leak was determined by the degree of damage inflicted upon the tip-link of the hair bundle during isolation. Excessive sodium accumulation may explain why OHCs cannot maintain their normal resting membrane potential in some experimental conditions. PMID- 9364549 TI - Evaluation of hyperactive caloric responses in patients with inner ear diseases. AB - Twenty-three patients with various types of inner ear diseases, who showed hyperactive caloric responses (21 patients showed unilateral hyperactive caloric responses, and 2 patients showed bilateral hyperactive caloric responses) were monitored during 2-10 years and underwent caloric tests repeatedly (2-7 times). None of them showed continuous hyperactivity of the labyrinth throughout their clinical courses. It seems that hyperactive caloric responses in patients who suffer from inner ear disease may be a transient phenomenon, caused by fluctuations of the vestibular condition, central compensation, age and/or mental state of the patients. PMID- 9364550 TI - Far-advanced otosclerosis. AB - Patients with 'far-advanced' or 'very far-advanced' otosclerosis have a profound bilateral hearing loss, with apparently no cochlear reserve measured by standard clinical audiometers. These patients have no benefit from a powerful hearing aid, have severe feedback problems and the cochlear implant may be the only solution. A total of 12 stapedotomies were performed in 8 patients with far-advanced or very far-advanced otosclerosis, with satisfactory results, improved air conduction thresholds and improved cochlear function and speech discrimination. Stapedotomy is a useful procedure for patients with far-advanced otosclerosis which improves patient's hearing to levels where they can benefit from less powerful hearing aids with fewer feedback problems, compared to no measurable preoperative hearing aid benefit. It also spares those patients being submitted to cochlear implantation. PMID- 9364552 TI - Castleman's disease: an unusual cause of a neck mass. AB - Castleman's disease is an unusual cause of a neck mass; in only 6% of the cases reported in the literature is the disease primarily located in the neck. We present 2 cases of Castleman's disease restricted to the neck, who underwent successful surgical excision. We discuss the histopathology in the different forms of the disease and review the literature. PMID- 9364551 TI - Perineurioma: an unusual cause of an external auditory canal polyp. AB - A 33-year-old woman presented with pruritus of the right ear and on examination was found to have 1 x 1 cm polypoid lesion in the external auditory canal. This was removed and histological examination revealed a well-circumscribed spindle cell lesion arranged in fascicles and whorls. Immunohistochemistry showed the tumor to be EMA-positive but S-100-, desmin-, actin-, and cytokeratin-negative. Ultrastructural examination confirmed perineurial cell origin. There are several lesions in which perineurial cells are present, but a true perineurioma is composed exclusively of perineurial cells. It has characteristic morphological, immunohistochemical and ultrastructural features that help separate it from other nerve and neuroectodermal lesions. PMID- 9364553 TI - Vaccination against Haemonchus contortus with denatured forms of the protective antigen H11. AB - As part of a systematic examination of the protective epitopes on H11, groups of sheep were vaccinated with preparations of purified H11 used untreated (group A), or progressively denatured (linearized) by incubation with sodium dodecyl sulphate (SDS) (group B) or by boiling with SDS in the presence of dithiothreitol (group C). All the sheep developed antibodies which bound to the untreated H11. When challenged with 10,000 infective larvae of Haemonchus contortus the mean levels of protection relative to the mean values for adjuvant controls were 99.8%, 85% and 79% for faecal egg counts and 95%, 79% and 54% for worm burden at post-mortem for groups A, B and C respectively. The H11-specific antibodies inhibited the microsomal aminopeptidase activity of H11 in vitro up to 80%. The levels of inhibition by sera from individual animals correlated with levels of protection with r2, of 0.69-0.87. PMID- 9364554 TI - Association between cellular response (IL-4) to RESA/Pf155 and protection from clinical malaria among Papua New Guinean children living in a malaria endemic area. AB - A prospective study in 207 children aged 0.5-15 years was carried out to examine the relationship between cellular responses to Plasmodium falciparum ring infected erythrocyte surface antigen (RESA) and malaria infection and morbidity. The prevalence of lymphoproliferative response to RESA was 13%, IFN-gamma prevalence was 40% and IL-4 prevalence was 22%. Only the IFN-gamma, response to RESA increased significantly with age. When proliferation or stimulation of either cytokine was used to assess T-cell activation the overall frequency of responders increased to 55%. The proliferative and IFN-gamma response to RESA were positively associated. Although there was no association between any of the CMI responses to RESA and concurrent morbidity the prevalence of IL-4 response to RESA was significantly lower in children who experienced clinical malaria in the following year. These results coupled with our earlier data showing a negative relationship between humoral responses to RESA and malaria morbidity support the inclusion of RESA in a subunit vaccine against malaria. PMID- 9364555 TI - A comparison of humoral responses to Schistosoma haematobium in areas with low and high levels of infection. AB - Antibody responses to Schistosoma haematobium of 280 Zimbabweans were studied in two areas of differing infection levels. 133 of the subjects came from a low infection area with a prevalence of 33.8% and geometric mean infection intensity of 0.8 eggs per 10ml of urine, while 147 of the subjects came from a high infection area with a prevalence of 62.7% and geometric mean intensity of 3.2 eggs per 10 ml of urine. Both the age-prevalence and age-intensity curves exhibited a peak shift. IgA, IgE, IgG, IgG1, IgG2, IgG3, IgG4, and IgM antibody levels against soluble egg antigen (SEA) and whole worm homogenate (WWH) were assayed by ELISA. Females produced significantly more anti-SEA IgG1, IgG4, IgM, anti-WWH IgE and IgG1. People from the high infection area produced significantly more anti-SEA IgE, IgG3 and anti-WWH IgG3 and significantly lower levels of anti SEA IgA, IgM and anti-WWH IgM when the effects of infection intensity, sex and age had been allowed for. The age profiles of anti-SEA IgA, IgG and anti-WWH IgA and IgM reflected current levels of infection while anti-WWH IgG1, IgG2 and anti SEA IgG1 evolved more slowly with age, and anti-WWH IgE rose with age in both areas. Some antibody responses, anti-SEA/WWH IgM, anti-SEA IgG1 and possibly anti SEA/ WWH IgA showed different age profiles in the two areas, with changes in antibody levels occurring at a younger age in the high infection area suggesting that immune responses are evolving more rapidly in residents of this area. This result clearly demonstrates that antibody levels are not a function of age alone. PMID- 9364556 TI - Sensitivity of Entamoeba histolytica and Entamoeba dispar patient isolates to human complement. AB - Twenty-one Entamoeba histolytica and 56 Entamoeba dispar patient isolates were investigated for their sensitivity to the classical and alternative pathway of human complement, E. histolytica and E. dispar patient isolates were differentiated by polymerase chain reaction and hexokinase isoenzyme typing. It was found that 90.3% (+/- 12.0%) of the trophozoites of E. histolytica were lysed after 30 min by the alternative pathway of complement in the presence of 50% human serum (19 isolates showed lysis rates higher than 80%), whereas E. dispar cells were less susceptible to the alternative pathway as 68.8% (+/- 28.2%) of lysis occurred. However, 23 of the E. dispar isolates were lysed between 100 and 80% (90.9% +/- 9.1%), demonstrating that about half of the tested E. dispar isolates were highly sensitive to complement lysis. Only 11 of the E. dispar isolates were proven to be ?resistant' to the alternative pathway of complement and were lysed less than 40%. These results are in conflict to earlier publications, describing resistance of E. dispar to complement lysis (Hamelmann et al. 1992, 1993). PMID- 9364557 TI - Immune response to the filaria Litomosoides sigmodontis in susceptible and resistant mice. AB - Comparisons were made between the immune responses evoked during the course of chronic and patient infections of Litomosoides sigmodontis in susceptible BALB/c mice and non-patent infections in resistant B10.D2 mice. Early antigen specific responses of spleen cells were weak in both mouse strains. However, by day 58 post infection a strong Th2 response, as determined by production of IL-4, IL-5 and IL-10, was observed in BALB/c mice but not in B10.D2 mice. Antibody responses seemed to appear sooner in B10.D2 than in BALB/c mice, and these differentially recognised two antigens of 15 kD and 80 kD. PMID- 9364558 TI - Identification of a surrogate TSL-1 antigen of Trichinella spiralis from a phage library of random peptides. AB - We sought to find a peptide analogue of an important antigen (TSL-1) of Trichinella spiralis which is recognized by the 7C2C5 antibody. A phage library which displays a short (15-mer) randomly-generated peptide at the filament of the minor coat protein of the virion was used for selection by the 7C2C5 antibody. A peptide thus identified, ICDASGLGCWCWSLSP, was found to be a true surrogate since its binding to the antibody could be blocked by the native antigen and, conversely, an antiserum made to the peptide could recognize the native antigen. In addition, the peptide appeared to detect T. spiralis-infected pigs although it was less discriminatory than the native antigen. PMID- 9364559 TI - Allograft responses can interfere with the development of immunity against Theileria annulata following vaccination with parasite infected cell lines. AB - Theileria annulata macroschizont-infected cell lines are successfully used as vaccines in several countries. The inoculated animals produce a strong allogeneic response against the MHC antigens of the immunizing cell line followed by an anti parasite response. Immunity against the parasite wanes in the absence of challenge and re-immunization is sometimes recommended. However, it is not known if allogeneic responses generated by the first immunization with a T. annulata infected cell line will interfere with the boosting of immunity against the parasite at the time of re-immunization with the same cell line. Animals were primed against MHC antigens by skin grafting, followed by immunization with a T. annulata infected cell line prepared from the skin donor. A strong anti-MHC response was produced. This interfered with parasite transfer and the development of an anti-parasite immune response; the effect was more marked when a low vaccine cell dose was used. There was a negative correlation between the ease of isolating infected cells from the animals after cell line immunization, and the subsequent response to challenge. Where no cell lines could be isolated, the animals were fully susceptible to sporozoite challenge. These observations are of immediate importance in endemic areas where cell lines of T. annulata schizonts are being used as vaccines to control the disease. PMID- 9364560 TI - Phylogenetic taxonomy of Leishmania (Viannia) braziliensis based on isoenzymatic study of 137 isolates. AB - Biochemical characterization of 137 Leishmania braziliensis isolates from South and Central America, and from selected endemic foci in Bolivia, Brazil and Colombia, performed by isoenzymatic electrophoresis using 10 enzymatic systems, showed a high enzymatic polymorphism (44 zymodemes obtained) based on the variation of a small number of enzymes. Cladistic analysis showed close links between the zymodemes within the L. braziliensis s.s. cluster. The position of 2 Colombian zymodemes obtained (MON*204 and MON*205) justify the inclusion of L. peruviana within the L. braziliensis cluster. PMID- 9364561 TI - Genomic DNA repeat from Leishmania (Viannia) braziliensis (Venezuelan strain) containing simple repeats and microsatellites. AB - In this paper the Leishmania (Viannia) braziliensis complex is defined as containing all species of the actual subgenus Viannia. Organisms of the L. (V) braziliensis complex are the causative agents of localized human cutaneous and mucocutaneous leishmaniasis in South America, much of Central America and some ares of North America. In our search for better species and subspecies diagnostic probes we focused our research on repetitive DNA, since it provides a greater number of target sites for hybridization. In this work we report the isolation and sequencing of a 1.8 kb DNA region, LbJ38, which is probably tandemly repeated or dispersed at least 4 times along one chromosome and is naturally present in L. (V) braziliensis genomic DNA. This region contains microsatellites and simple repeat DNA sequences and was isolated by screening a genomic DNA cosmid library with complex- and species-specific probes. No homology was found with other Leishmania microsatellite or repetitive DNA. The utility of this repetitive sequence and primers derived from it in the identification of L. (V) braziliensis is demonstrated. As far as we are aware, this is the first report of sequence characterized repetitive microsatellite and GC rich simple repeat DNA from the nuclear genome of New World Leishmania. PMID- 9364562 TI - A novel role for the peritrophic matrix in protecting Leishmania from the hydrolytic activities of the sand fly midgut. AB - The role of the peritrophic matrix (PM) in the development of Leishmania major infections in a natural vector, Phlebotomus papatasi, was investigated by addition of exogenous chitinase to the bloodmeal, which completely blocked PM formation. Surprisingly, the absence of the PM was associated with the loss of midgut infections. The chitinase was not directly toxic to the parasite, nor were midgut infections lost due to premature expulsion of the bloodmeal. Most parasites were killed in chitinase-treated flies within the first 4 h after feeding. Substantial early killing was also observed in control flies, suggesting that the lack of PM exacerbates lethal conditions which normally exist in the blood-fed midgut. Early parasite mortality was reversed by soybean trypsin inhibitor. Allosamadin, a specific inhibitor of chitinase, led to a thickening of the PM, and also prevented the early parasite mortality seen in infected flies. Susceptibility to gut proteases was extremely high in transitional-stage parasites, while amastigotes and fully transformed promastigotes were relatively resistant. A novel role for the PM in promoting parasite survival is suggested, in which the PM creates a barrier to the rapid diffusion of digestive enzymes, and limits the exposure of parasites to these enzymes during the time when they are especially vulnerable to proteolytic damage. PMID- 9364563 TI - Identification and partial characterization of a 36 kDa surface protein on Neospora caninum tachyzoites. AB - Neospora caninum, the causative agent of neosporosis, is a recently identified apicomplexan parasite which is structurally and biologically closely related to, but antigenically distinct from, Toxoplasma gondii. Molecules associated with the surfaces of N. caninum tachyzoites are likely to participate in the host cell entry process, could be involved in the interaction of the parasite with the immune system, and they could influence the pathogenesis of neosporosis. Isolated N. caninum tachyzoites were extracted with the non-ionic detergent Triton X-114 and were further analysed using a polyclonal anti-N. caninum antiserum. Immunoblots revealed several reactive bands, 1 of which represented a glycoprotein of approximately 36 kDa (Nc-p36). This molecule was present in 2 isolates of Neospora (NC-1 and Liverpool), but was absent in Toxoplasma (RH strain) tachyzoites. Immunofluorescence and pre-embedding immunogold transmission electron microscopy employing affinity-purified anti-Nc-p36 antibodies showed that the Nc-p36 is a cell surface-associated protein. Immunogold on-section labelling of LR-White-embedded parasites, fixed prior and at defined time-points after host cell entry, demonstrated the presence of this molecule on the surface as well as within the dense granules of N. caninum tachyzoites. PMID- 9364564 TI - The effect of salinity on transovarial transmission of a microsporidian infecting Gammarus duebeni. AB - This is an investigation of the impact of salinity on transovarial transmission and burden of a microsporidian sex ratio distorter in the inter-tidal crustacean Gammarus duebeni. Exposure of parasitized mothers to increased salinity during the gonotrophic cycle caused an increase in parasite burden in the follicle cells and a decrease in burden in the oocytes. It appears that salinity impedes parasite transmission from the follicle cells to the oocytes during host oogenesis. A lower proportion of the young were infected in broods from elevated salinity and, in infected offspring, parasite burden was lower than in control embryos. Parasite replication occurred during embryogenesis. However, the pattern of parasite growth did not differ between salinities, indicating that differences in parasite burden could be attributed to a reduction in the initial parasite burden transmitted to the gamete, rather than to a reduction in parasite replication during host embryogenesis. We discuss our findings with respect to parasite/host dynamics and the ecology of the host. PMID- 9364565 TI - Monoclonal antibodies multireactive with parasite antigens produced by hybridomas generated from naive mice. AB - Hybridoma clones producing IgM naturally occurring (natural) antibodies were generated from naive Balb/c mice and characterized for reactivity against parasite antigens. Ascites of mice injected with these hybridomas reacted with Toxoplasma gondii soluble antigen at levels approximately 1000-10,000 times higher than serum pooled from mice used for generating hybridomas as determined by a conventional enzyme-linked immunosorbent assay. Western blot analysis indicated that these monoclonal antibodies reacted with multiple antigen molecules of T. gondii with patterns similar to that of pooled mouse sera. These antibodies also reacted with multiple antigens of Plasmodium yoelii, Entamoeba histolytica, Ascaris lumbricoides, Toxocara canis, Trichuris vulpis, Fasciola hepatica, Schistosoma mansoni, and Dipylidium caninum. When one monoclonal antibody was absorbed with these parasite antigens, its reactivity with T. gondii antigen molecules was consistently reduced, independent of parasite species. These natural antibodies failed to kill T. gondii tachyzoites in vitro or to protect mice from lethal challenge with T. gondii. These results indicate that natural antibodies detected in sera of naive mice are secreted from certain B cell populations and that these antibodies are multireactive with parasite antigens and have low affinity. PMID- 9364566 TI - Molecular characterization of a partial sequence encoding a novel Schistosoma mansoni serine protease. AB - A PCR strategy using degenerate oligonucleotide primers based upon consensus sequences of the active site of serine proteases yielded a 467 bp fragment from genomic DNA from Schistosoma mansoni cercariae. The sequence presented a continuous open reading frame and the deduced amino acid sequence (156 aa) presented homologies with various serine proteases, in particular the highest percentage identity was observed with a mammalian plasma kallikrein. The expression of this serine protease was studied first at the mRNA level and it was only detected by RT-PCR in cercariae and in adult worms. At the protein level we were able to detect it by Western blotting and by using antigen extracts from metabolically radio-isotope labelled worms. The absence of any positive signal in Northern blot and the detection of the protein suggest that the mRNA has a very short half-life, however the protein may be accumulated in the parasite. The significance of identity with mammalian kallikrein was confirmed by cross immunoreactivity with a native porcine pancreatic kallikrein. However, no cross reactivity was observed with S. mansoni elastase, another serine protease. Thus, we suggest that the serine protease described in this paper is a kallikrein-like protease. PMID- 9364567 TI - Classification of plant trypanosomatids (Phytomonas spp.): parity between random primer DNA typing and multilocus enzyme electrophoresis. AB - The genetic polymorphism of 30 isolates of plant trypanosomatids colloquially referred to as plant trypanosomes was assayed by means of RAPD. The principle objectives of this study were to assess the discriminative power of RAPD analysis for studying plant trypanosomes and to determine whether the results obtained were comparable with those from a previous isoenzyme (MLEE) study. The principle groups of plant trypanosomes identified previously by isoenzyme analysis- intraphloemic trypanosomes, intralaticiferous trypanosomes and trypanosomes isolated from fruits--were also clearly separated by the RAPD technique. Moreover, the results showed a fair parity between MLEE and RAPD data (coefficient of correlation = 0.84) and the two techniques have comparable discriminative ability. Most of the separation revealed by the two techniques between the clusters was associated with major biological properties. However, the RAPD technique gave a more coherent separation than MLEE because the intraphloemic isolates, which were biologically similar in terms of their specific localization in the sieve tubes of the plant, were found to be in closer groups by the RAPD. For both techniques, the existence of the main clusters was correlated with the existence of synapomorphic characters, which could be used as powerful tools in taxonomy and epidemiology. PMID- 9364568 TI - Geographical genetic structure within the human lung fluke, Paragonimus westermani, detected from DNA sequences. AB - Nucleotide sequences were obtained for the second internal transcribed spacer of the ribosomal gene repeat and for part of the mitochondrial-cytochrome c oxidase subunit I gene from geographical isolates of Paragonimus westermani from Japan, China, Korea, Taiwan, the Philippines, peninsular Malaysia and Thailand. Sequences were obtained from several other species of Paragonimus for comparative purposes. Two groups were recognized within P. westermani: an NE group (China, Japan, Korea, Taiwan) which was relatively uniform and included both diploid and triploid forms, and a southern group (Malaysia, Thailand, Philippines), members of which were genetically distant from one another. According to both ITS2 and COI data, genetic distances among P. westermani isolates equalled or exceeded those between some distinct species of Paragonimus. The ITS2 sequences were conserved relative to COI sequences. Substitutions among the latter may be approaching saturation within the genus Paragonimus. PMID- 9364569 TI - The coevolutionary potential of a 'generalist' parasite, the hen flea Ceratophyllus gallinae. AB - Hosts exert selection pressures on their parasites and it is often assumed that host-parasite coevolution with each host is less intense in a generalist parasite than for a parasite with a narrow host range. Selection pressure on the parasite, however, is rather determined by host specificity, i.e. the relative importance of each host, than simply by the range of hosts. The determination of host specificity requires an assessment of the prevalence and intensity of parasite infestation within each host's nests, as well as the local abundance of each host species. Since the hen flea, Ceratophyllus gallinae, is a rather generalist parasite of birds it could be concluded that there has been weak coevolution with each of its hosts. By reviewing the literature on the prevalence and intensity of hen flea infestations in bird nests we estimated the number of individuals produced in the nest of each host species. The comparative analysis shows (1) that the prevalence of infestation is highest in hole-nesting avian families, (2) that prevalence and intensity of infestation among bird families are highly correlated, and (3) that hole-nesting Paridae have the highest intensities of infestation and harbour the majority of the flea population. These results underline the fleas' potential for coevolution with Paridae despite their extensive host range. PMID- 9364570 TI - Isolation and characterization of secretions from the plant-parasitic nematode Globodera pallida. AB - Electrophoresis of secretions collected from Globodera pallida revealed a smeared region between 25 and 50 kDa, and a single band of < 20 kDa. The secretions were used to raise an antiserum (LW1). Immunoblotting of parasite homogenates with LW1 differentiated G. pallida from its sibling species G. rostochiensis and revealed differences between different populations of G. pallida and G. rostochiensis. Indirect immunofluorescence studies with LW1 indicated that at least some of the secretions were surface localized and that antibody binding to the nematode surface was periodate sensitive. Periodate sensitivity indicated that these differences could be due to glycosylation differences. Glycosylation differences were also detected by blotting nematode homogenates with the lectin wheat germ agglutinin (WGA), WGA was also able to differentiate between G. rostochiensis which gave 2 bands at 130 kDa and 110 kDa, and G. pallida which produced 2 bands present at 120 kDa and 110 kDa. Further localization studies using immunoelectron microscopy demonstrated that antibody binding could be seen to secretions found in the pump chamber of the metacorpal bulb at the base of the stylet. From further specimens it could be observed that the contents of the subventral glands were heavily labelled, indicating that the material seen in the metacorpal bulb had originated from the subventral glands. PMID- 9364571 TI - Sex-manipulated Ascaris suum infections in pigs: implications for reproduction. AB - In spite of the vast distribution and considerable impact on human and animal health of Ascaris suum and A. lumbricoides, little is known of the sexual biology and reproductive capacity of these intestinal nematodes. By oral transfer of adult female worms to previously parasite-naive pigs we show that in the absence of males the egg production ceases after 2-3 weeks. Such females readily resume egg production a few days after oral transfer of male worms. These observations throw light on an important aspect of Ascaris biology, but also pave the way for possible experimental interbreeding between the human and pig Ascaris species. PMID- 9364572 TI - Experimental Ascaris suum infection in the pig: worm population kinetics following single inoculations with three doses of infective eggs. AB - To study population kinetics during primary Ascaris suum infections, 3 groups of 52 pigs each were inoculated with 100, 1000, or 10,000 infective eggs. In all groups, the majority of larvae was found in the liver on day 3 post inoculation (p.i.) and in the lungs on day 7 p.i. Liver white spots, caused by migrating larvae, were most numerous at day 7 p.i., whereafter they gradually healed, and only low numbers of granulation-tissue type white spots and lymphonodular white spots persisted at days 21-56 p.i. Independent of dose level, 47-58% of the inoculated eggs were recovered as larvae in the small intestine on day 10 p.i., but most larvae were eliminated at days 17-21 p.i. This elimination started earlier and removed a higher percentage of the worms with increasing inoculation dose, resulting in small strongly aggregated worm populations by day 28 p.i. (k of the negative binomial distribution was low: 0.2-0.4) without significant differences between groups. Thus, overdispersion, which is a characteristic of both porcine and human ascarosis, is found here under experimental conditions where aggregation factors like host behaviour, transmission rate, host status etc have been partly or totally controlled. PMID- 9364573 TI - A comparative analysis of parasite species richness of Iberian rodents. AB - Data on parasites of rodents, collected over an 18-year period on the Iberian peninsula, were used to find the determinants of parasite species richness. A total of 77 species of helminth parasites (nematodes, cestodes and digeneans) was identified among 16 species of rodents. Parasites were classified into groups according to their specificity towards their host and their life-cycle. A working phylogeny of the rodents was proposed on the basis of molecular and paleontological data and for each host the following parameters were recorded: sample size, weight, geographical range, longevity, and life-style. Two comparative methods were used, the independent comparisons method of Pagel (1992) and the distance matrix method of Legendre, Lapointe & Casgrain (1995). The second method has the advantage of measuring the relative contribution of phylogeny. Both methods gave similar results. Overall parasite species richness correlated only with host sample size. Host body size does not correlate with any subset of parasite species richness. However, host phylogeny is a good predicator of specific parasites and the species richness of digeneans correlates with host geographical range. A phylogenetic reconstruction of host relations was performed using the parasites belonging to subgroups in which richness is correlated with host phylogeny. These parasite species were treated as Dollo characters, i.e. we made the assumption that the loss of a parasite species is irreversible. The consensus tree obtained reflects the major phylogenetic divisions of the host group. Finally, this study illustrates the relative importance of processes acting at different temporal and spatial scales (evolutionary time and actual geographical range of hosts) in determining the structure of helminth parasite fauna. PMID- 9364574 TI - Platelet prostanoid receptors. AB - Prostaglandins (PGs) and thromboxanes are important modulators of platelet activation, and there is strong evidence to support the existence of distinct thromboxane, prostacyclin, PGD2 and PGE2 receptors on the platelet plasma membrane. In this review, each of these platelet prostanoid receptors is discussed in detail, with respect to their receptor pharmacology, molecular biology and signal transduction, and as to any therapeutic implications of the development of specific agonists and/or antagonists. In addition, it considers the possibility that there are separate vascular receptors for 8-epi PGF2 alpha, which are not present on the platelet. PMID- 9364575 TI - Cerebral vessels in ageing and Alzheimer's disease. AB - The integrity of the cerebral vasculature is crucial to the maintenance of cognitive functions during ageing. Prevailing evidence suggests that cerebrovascular functions decline during normal ageing, with pronounced effects in Alzheimer's disease (AD). The causes of these changes largely remain unknown. While previous studies recorded ageing-related impairments, such as atherosclerosis and loss of innervation in basal surface arteries of the brain, it only recently has been realized that a number of subtle alterations in both the intracranial resistance vessels and the smaller capillaries is apparent in both ageing animals and humans. The dominant changes include alterations in composition of connective tissues and smooth muscle of large vessel walls, thickening of the vascular basement membrane, thinning of the endothelium in some species, loss of endothelial mitochondria and increased pericytes. Some of these attributes appear more affected in AD. Other abnormalities entail profound irregularities in the course of microvessels, unexplained inclusions in the basement membrane and changes in unique proteins and membrane lipids associated with the blood-brain barrier. Brain imaging and permeability studies show no clear functional evidence to support the structural and biochemical anomalies, but it is plausible that focal and transient breach of the blood-brain barrier in ageing, and more notably in AD, occurs. Thus, circumscribed neuronal populations in certain brain regions could become vulnerable. Furthermore, the characteristic deposition of amyloid in vessels in AD may exacerbate the decline in vascular function and promote chronic hypoperfusion. Although not explicit from current studies, it is likely that the brain vasculature is continually modified by growth and repair mechanisms in attempts to maintain perfusion during ageing and disease. PMID- 9364576 TI - Alpha-adrenoceptors and vascular regulation: molecular, pharmacologic and clinical correlates. AB - This manuscript is intended to provide a comprehensive review of the alpha adrenoceptors (ARs) and their role in vascular regulation. The historical development of the concept of receptors and the division of the alpha-ARs into alpha 1 and alpha 2 subtypes is traced. Emphasis will be placed on current understanding of the specific contribution of discrete alpha 1- and alpha 2-AR subtypes in the regulation of the vasculature, selective agonists and antagonists for these receptors, the second messengers utilized by these receptors, the myoplasmic calcium pathways activated to initiate smooth muscle contraction, as well as the clinical uses of agonists and antagonists that work at these receptors. New information is presented that deals with the molecular aspects of ligand interactions with specific subdomains of these receptors, as well as mRNA distribution and the regulation of alpha 1- and alpha 2-AR gene transcription and translation. PMID- 9364577 TI - Potential role of adenosine antagonist therapy in pathological tremor disorders. AB - The continuing lack of effective long-term therapies for Parkinson's disease and other disorders in which a primary symptom is involuntary tremor is leading to a search for alternative pharmacological strategies. Adenosine is a major modulator of neuronal activity and neurotransmitter release in the central nervous system, with A1 receptors inhibiting transmitter release and A2 receptors generally enhancing release of several transmitter systems relevant to the control of movement. The A2a subtype of receptor is especially concentrated in the neostriatum and is co-localised with D2 receptors for dopamine, the affinity of which are reduced by activation of the A2a population. Antagonists of adenosine, such as theophylline, have been reported to improve the tremor in cases of Parkinson's disease and essential tremor, and the development of better and more selective A2a receptor antagonists may prove of value in these disabling disorders. PMID- 9364578 TI - Chronic neuropathic pain and its control by drugs. AB - The medical treatment and some currently known aspects of the aetiology of five neurogenic pain states are discussed. Neurogenic pain can be described as pain resulting from noninflammatory dysfunction of the peripheral or central nervous system without nociceptor stimulation or trauma. The enormity of the field has limited this review to post-herpetic neuralgia, complex regional pain syndromes, phantom pain, trigeminal neuralgia and diabetic neuralgia. Evidence suggests that many neurogenic pain states are not effectively controlled. This may be due in part to a lack of understanding of the aetiology of these conditions and to the lack of high quality studies evaluating existing treatments. A compact review of the literature is presented with some treatment options and possible future directions. Where appropriate surgical management and physical therapy have been discussed; however, a thorough appraisal of nondrug treatments was not the main priority of this review. PMID- 9364580 TI - Molecular genetics of the renin-angiotensin system: implications for angiotensin II receptor blockade. AB - Angiotensin II (Ang II) is the main effector hormone of the renin-angiotensin system (RAS). The pathogenesis of many cardiovascular diseases, including heart failure and hypertension, appear to be related to Ang II production. The generation of Ang II involves angiotensin-converting enzyme (ACE) in circulating and tissue RAS's, as well as non-ACE pathways. ACE and other components of the RAS show natural mutations. In this review, we discuss the molecular genetics of the human RAS in relation to cardiovascular disease, including the clinical effects of known ACE molecular variants and possible pharmacological treatment strategies. PMID- 9364579 TI - Transforming growth factor-beta signaling in epithelial cells. AB - Transforming growth factor (TGF)-beta is a potent growth suppressor of epithelial cells. Resistance to TGF-beta, however, occurs frequently in solid tumors of epithelial origin and contributes to the uncontrolled growth of these tumors. Although mutant receptor proteins contribute to TGF-beta insensitivity, deregulation of TGF-beta signaling cascades represents an equally important mechanism underlying TGF-beta resistance. Identification of abnormal regulation of signaling components in tumor epithelial cells will lead to the development of selective therapeutic approaches to repair the relevant signaling cascade(s) and reverse the growth anomaly. Within the past few years, great strides have been made in defining signaling pathways for TGF-beta. For example, our laboratory has demonstrated a direct correlation between TGF-beta-mediated growth inhibition of epithelial cells and activation of Ras and three members of the mitogen-activated protein kinase (MAPK) superfamily. The TGF-beta signaling events were sustained, dose-dependent, and absent in TGF-beta-resistant cells. Further, up-regulation of both p27Kip1 and p21Cip1, nuclear events important for the growth inhibitory effect of TGF-beta, are completely dependent upon the activation of Ras. However, Ras-independent pathways are also activated simultaneously with the Ras/MAPK pathways to mediate the final TGF-beta growth inhibitory outcome. One such pathway includes the SMAD signaling components that control TGF-beta-mediated gene transcription, currently under active study by a number of laboratories, including our own. Future efforts in this field will focus on defining the significance of these signaling proteins and pathways in mediating specific TGF beta responses. Moreover, additional novel signaling proteins are sure to be identified. PMID- 9364581 TI - In vitro evidence for vascular hyporesponsiveness in clinical and experimental cirrhosis. AB - The mechanisms responsible for vascular hyporesponsiveness in cirrhosis have been investigated extensively using isolated vessel techniques. Increased vasodilator (nitric oxide) production has been implicated in many studies, but there is also evidence of altered receptor/second messenger function and vascular remodelling. Interpretation is hampered by the use of different vessels from a variety of animal models, whilst the relevance of these studies to the condition in humans remains unclear. Additional, more focused investigations, using both human and animal vessels, are required to ascertain the exact cause of the vascular abnormalities associated with hepatic cirrhosis. PMID- 9364582 TI - Matrix metalloproteinase inhibition as a novel anticancer strategy: a review with special focus on batimastat and marimastat. AB - Matrix metalloproteinases (MMPs) are a homologous family of enzymes that are involved in tissue remodeling and morphogenesis. Collectively, these enzymes are capable of degrading all components of the extracellular matrix, and they play an important role in normal physiologic conditions, such as wound healing and other processes involving tissue remodeling. However, increased activity of these enzymes now has been observed in a number of different pathological conditions, and it has been hypothesized that such increased activity of MMPs might play a role in the pathogenesis of these conditions. Cancer is one such condition; extracellular matrices constitute the principal barrier to tumor growth and spread, and there is growing experimental evidence that malignant tumors utilize MMPs to overcome these barriers. Consequently, inhibitors of MMPs represent an attractive target for a new class of anticancer agents. Marimastat and batimastat are potent broad-spectrum inhibitors of all major MMPs and have been shown to prevent or reduce spread and growth of a number of different malignant tumors in numerous animal models. Both agents are now in advanced clinical testing in a number of different solid tumors in North America and Europe. The purpose of this paper is to review available preclinical and emerging clinical data, using batimastat and marimastat as prototype MMP inhibitors in the cancer area. PMID- 9364583 TI - Quantification of mean energy and photon contamination for accurate dosimetry of high-energy electron beams. AB - The scientific background of the standard procedure for determination of the mean electron energy at the phantom surface (E0) from the half-value depth (R50) has been studied. The influence of energy, angular spread and range straggling on the shape of the depth dose distribution and the R50 and Rp ranges is described using the simple Gaussian range straggling model. The relation between the R50 and Rp ranges is derived in terms of the variance of the range straggling distribution. By describing the mean energy imparted by the electrons both as a surface integral over the incident energy fluence and as a volume integral over the associated absorbed dose distribution, the relation between E0 and different range concepts, such as R50 and the maximum dose and the surface dose related mean energy deposition ranges, Rm and R0, is analysed. In particular the influence of multiple electron scatter and phantom generated bremsstrahlung on R50 is derived. A simple analytical expression is derived for the ratio of the incident electron energy to the half-value depth. Also, an analytical expression is derived for the maximum energy deposition in monoenergetic plane-parallel electron beams in water for energies between 2 and 50 MeV. Simple linear relations describing the relative absorbed dose and mass ionization at the depth of the practical range deposited by the bremsstrahlung photons generated in the phantom are derived as a function of the incident electron energy. With these relations and a measurement of the extrapolated photon background at Rp, the treatment head generated bremsstrahlung distribution can be determined. The identification of this photon contamination allows an accurate calculation of the absorbed dose in electron beams with a high bremsstrahlung contamination by accounting for the difference in stopping power ratios between a clean electron beam and the photon contamination. The absorbed dose determined using ionization chambers in heavily photon contaminated (10%) electron beams may be too low--by as much as 1.5%--without correction. PMID- 9364584 TI - Build-up cap materials for measurement of photon head-scatter factors. AB - The suitability of high-Z materials as build-up caps for head-scatter measurements has been investigated. Build-up caps are often used to enable characterization of fields too small for a mini-phantom. We have studied lead and brass build-up caps with sufficiently large wall thicknesses, as compared to the range of contaminating electrons originating in the accelerator head, and compared them with build-up caps made of ionization chamber equivalent materials, i.e. graphite. The results were also compared with measurements taken using square and cylindrical polystyrene mini-phantoms. Field sizes ranging from 3 cm x 3 cm up to 40 cm x 40 cm were studied for nominal photon energies of 4, 6, 10 and 18 MV. The results show that the use of lead and brass build-up caps produces normalized head-scatter data slightly different from graphite build-up caps for large fields at high photon energies. At lower energies, however, no significant differences were found. The intercomparison between the two different plastic mini-phantoms and graphite caps showed no differences. PMID- 9364585 TI - Radiochromic film dosimetry for verification of dose distributions delivered with proton-beam radiosurgery. AB - In this work we studied the feasibility of radiochromic film for dosimetry verification of proton Bragg peak stereotactic radiosurgery with multiple beams. High-sensitivity MD-55 radiochromic film was calibrated for proton beam irradiation and the RIT 113 system was employed for film evaluation. Simulated stereotactic radiosurgery with a special phantom arrangement for film dosimetry was performed, following the same procedure as for a patient undergoing treatment. Five-beam irradiation was developed using a 3D treatment planning system. This plan was then delivered to the phantom in a one-day experiment. Planned and measured composite dose distributions were compared. Spatial accuracy of dose delivery to a region containing a simulated critical structure was evaluated for a single portal. Radiochromic film dosimetry validated the prescribed dose delivery within +/- 5%, one standard deviation, by comparing calculated doses with measured values. The alignment of apertures and boluses, as well as the alignment of the phantom with respect to the isocentre, was confirmed. Spatial accuracy of the method would have been able to detect possible misalignments greater than +/- 2 mm. We have demonstrated how radiochromic film dosimetry can be used to measure complex dose distributions in an irradiated phantom, thus enabling us to verify planned dose delivery of proton Bragg peak stereotactic radiosurgery with multiple beams. We assume that the dosimetric agreement between planned and measured dose distributions for the reported simulations will apply to patient treatments. PMID- 9364586 TI - Alpha-particle dosimetry for the basal layer of the skin and the radon progeny 218-Po and 214-Po. AB - The population average dose to the basal layer of the skin is evaluated, in terms of dose per alpha-particle decay per unit area, for radon progeny 218-Po and 214 Po attached to the skin surface. Account is taken of the variation in basal layer depth between different individuals, and results are presented for several anatomical regions. On the face, for example, the population average dose to the basal layer from 218-Po is of the order of 0.5 microSv/decay/cm2 while that from 214-Po is of the order of 1 microSv/decay/cm2. Radiation induced stochastic effects in the skin are generally assumed to originate from target cells located in the basal layer. Provided this assumption is correct, these results suggest that both 218-Po and 214-Po could be regarded as potential carcinogenic agents for the induction of skin cancer. PMID- 9364587 TI - A Monte Carlo study of the quality dependence of diamond thermoluminescent dosimeters in radiotherapy beams. AB - Monte Carlo simulations with the EGS4 code system have been performed to determine the quality dependence of diamond TLDs in photon beams ranging from 25 kV to 25 MV x-rays and also in megavoltage electron beams. It has been shown that diamond TLDs in the form of discs of thickness 0.3 mm and diameter 5.64 mm show no significant dependence on the incident energy in clinical electron beams when irradiated close to dmax, but require an energy correction factor of 1.050 +/- 0.008 compared with diamond TLDs irradiated in 60Co gamma-rays. The correction factor increases with depth of irradiation and this effect is greater for thicker detectors. The Monte Carlo predicted sensitivity in x-ray beams is constant within 2.5% over the energy range 250 kV to 25 MV. However the sensitivity decreases by about 60% for 25 kV x-rays compared with 60Co gamma-rays. PMID- 9364588 TI - General collection efficiency for liquid isooctane and tetramethylsilane in pulsed radiation. AB - The general collection efficiency in pulsed radiation was studied for isooctane (C8H18) and tetramethylsilane (Si(CH3)4). These two liquids were used as sensitive media in a parallel-plate liquid ionization chamber with a 1 mm sensitive layer. Measurements were carried out using 20 MV photon radiation from a linear accelerator with a pulse repetition frequency of 30 pulses/second and a pulse length of 3.5 microseconds. The general collection efficiency was determined for polarizing voltages in the interval 1000-2000 V for isooctane and 500-2000 V for tetramethylsilane and for pulse doses in the interval 0.06-1.9 mGy/pulse. An air ionization chamber was used as a pulse dose reference monitor. The experimental results were compared with those predicted by the equation for the general collection efficiency for gases in pulsed radiation, using the permittivity of each of the liquids. It was found that for general collection efficiencies down to 80% the differences between the predicted and experimental general collection efficiencies in the two liquids were within +/- 1% at electric field strengths exceeding 10(6) V m-1. PMID- 9364589 TI - A time-scale sensitometric method for evaluating screen-film systems. AB - An x-ray sensitometer is used to measure the characteristic curve of radiographic films exposed with fluorescent intensifying screens. The series of relative exposures, necessary to cover the full density range of the film, can be obtained by either time-scale or intensity-scale sensitometric methods. We have developed a convenient method of exposing film-screen systems for time-scale sensitometry. In this method, during exposure the x-ray kilovoltage, tube current and x-ray intensity remain constant and a geometric series of exposures of the film is modulated by varying the exposure time. This time variation can be obtained when a lead disc with different sector openings is rotated in front of the film system by a stepping motor. The conditions normally used are 70 kVp x-rays, 3.5 mm Al total filtration at the tube, and 2.4 m focal spot-film distance. This exposure latitude gives a complete characteristic curve of film-screen systems. PMID- 9364590 TI - A comparison between the patella and the calcaneus using ultrasound velocity and attenuation as predictors of bone mineral density. AB - The bone mineral density (BMD), ultrasound velocity (UV) and attenuation were examined in sixteen matched sets of human patellae and calcanei. For the sixteen calcanei, BMD was strongly correlated with all ultrasound parameters. Calcaneal UV appeared to be inferior to attenuation in the ability to predict BMD. For the sixteen patellae, the average UV was found to be greater in the superior/inferior direction than in the anterior/posterior and medial/lateral directions. It was found that patella BMD was significantly correlated with each of three directional ultrasound velocities. The relationship between BMD and ultrasound attenuation parameters was not significant in the patella. A comparative study of the two different bone sets demonstrated that the BMDs of the patella and calcaneus were significantly correlated with each other. Ultrasound velocity of calcaneus, measured in the medial/lateral direction, was not significantly associated with any of three directional ultrasound velocities in the patella. Similarly, ultrasound attenuation parameters of calcaneus were not significantly correlated with those of patella. The present study also demonstrated evidence that when predicting BMDs at their respective sites using ultrasound, the calcaneus appeared to be superior to the patella. PMID- 9364591 TI - The determination of the effective attenuation coefficient from effective organ depth and modulation transfer function in gamma camera imaging. AB - Absolute measurement of activity implies a determination of effective depths and effective attenuation coefficients. In order to define restoration filters, it is necessary to measure the transfer function, i.e. position a line source at an effective depth for the specific measurement situation. A phantom was designed which can simulate an organ with a certain thickness at a certain depth. The phantom was used to measure transfer functions and a comparison was made with transfer functions from a line source to determine effective depths. Effective attenuation coefficients were calculated for 99mTc, 111In and 201Tl for different organ thicknesses and depths of simulated organs. The effective attenuation coefficient for 99mTc was found to be 0.124 +/- 0.006 cm-1, in good agreement with previously published values. For 111In, the attenuation coefficient decreased with the depth of an organ due to the use of two energy windows in the measurements and a corresponding change in mean photon energy by depth. For 201Tl, the attenuation coefficient decreased with increasing organ thickness due to the increasing fraction of scattered radiation in the 40% energy window used. Using attenuation coefficients of 0.124, 0.184 and 0.11 cm-1 for 99mTc, 201Tl and 111In respectively, the derived equations can be used to calculate the position of a conventional line source for measurements of transfer functions for a specific organ with a certain thickness at a certain depth for definition of different types of restoration filter. PMID- 9364592 TI - Simultaneous PET and MR imaging. AB - We have developed a prototype PET detector which is compatible with a clinical MRI system to provide simultaneous PET and MR imaging. This single-slice PET system consists of 48 2 x 2 x 10 mm3 LSO crystals in a 38 mm diameter ring configuration that can be placed inside the receiver coil of the MRI system, coupled to three multi-channel photomultipliers housed outside the main magnetic field via 4 m long and 2 mm diameter optical fibres. The PET system exhibits 2 mm spatial resolution, 41% energy resolution at 511 keV and 20 ns timing resolution. Simultaneous PET and MR phantom images were successfully acquired. PMID- 9364593 TI - A solid tissue phantom for photon migration studies. AB - A solid tissue phantom made of agar, Intralipid and black ink is described and characterized. The preparation procedure is fast and easily implemented with standard laboratory equipment. An instrumentation for time-resolved transmittance measurements was used to determine the optical properties of the phantom. The absorption and the reduced scattering coefficients are linear with the ink and Intralipid concentrations, respectively. A systematic decrease of the reduced scattering coefficient dependent on the agar content is observed, but can easily be managed. The phantom is highly homogeneous and shows good repeatability among different preparations. Moreover, agar inclusions can be easily embedded in either solid or liquid matrixes, and no artefacts are caused by the solid-solid or solid-liquid interfaces. This allows one to produce reliable and realistic inhomogeneous phantoms with known optical properties, particularly interesting for studies on optical imaging through turbid media. PMID- 9364594 TI - A fast autofocus unit for fluorescence microscopy. AB - In this paper a fast autofocus unit is introduced for fluorescence microscopy based on image content information. The module, an electronic board with several differentiators and integrators, is designed for high-speed autofocusing and is directly coupled to the output of the video camera. A Leitz MPV II fluorescence microscope with x, y, z stepping motors was used as basic equipment. The microscope images were focused by using an intensified target camera with a following analogue-digital converter and a PC. Thus one obtains a focus value for the current image within one video cycle. Furthermore, it is possible to process three different focus functions (weighted intensity, first derivative and second derivative) simultaneously. The flexibility to select a certain focus function or a combination of these functions allows the use of the analogue detector for various cell types and fluorescent dyes. In order to test the experimental set-up we use three different kinds of biological specimen (lymphocytes, fibroblasts and comet cells) which are distinguished by large differences in their morphological structure. Successful focusing is carried out in more than 95% of cases (investigation of several hundred different cells). The focusing procedure is almost finished after 1-2 s. PMID- 9364595 TI - Application of the zooming method in near-infrared imaging. AB - Images of a tissue simulating phantom are obtained by inverting a limited number of continuous-wave relative transmission measurements. The diffusion approximation to the radiative transfer equation is used as a light propagation model. The inversion procedure is based on a quasi-Newton method and the Levenberg-Marquardt method, and the imaging parameter is the absorption coefficient of the phantom. It is shown that the resolution of the images can be improved using the zooming method. The image indicates the presence of an inhomogeneity in approximately the correct location, but the shape and size of the inhomogeneity in the reconstructed image differs from the shape and size of the actual inhomogeneity. Possible methods for further enhancement of the images are discussed. PMID- 9364596 TI - Oxygen and placental villous development: origins of fetal hypoxia. AB - The increasing practice of preterm delivery in the fetal interest for conditions such as pre-eclampsia or intrauterine growth restriction (IUGR) has provided an opportunity to study placental structure in pregnancies with prenatal evidence of fetal compromise. These data suggest that the origin of fetal hypoxia in IUGR with absent end-diastolic flow in the umbilical arteries is due to a failure of oxygen transport from intervillous space to umbilical vein. Failure of the fetoplacental circulation to extract oxygen from the intervillous space under such circumstances means intervillous PO2 is closer to maternal arterial values than under physiological conditions. Correspondingly the placental villi are chronically exposed to a higher oxygen tension than under normal circumstances- the term ?hyperoxia', relative to normal intraplacental oxygenation, is proposed to describe this situation. Both the trophoblast and villous core react to increased oxygen despite fetal hypoxia. These results challenge the generally accepted concept of ?placental hypoxia' in all circumstances where fetal hypoxia might arise. Therefore three categories are proposed for the origins of fetal hypoxia: (1) preplacental hypoxia; (2) uteroplacental hypoxia; and (3) postplacental hypoxia. Examples for these three disease states are listed in this review and the structural reaction patterns of placental villi to these differences in oxygenation are discussed. PMID- 9364597 TI - Role of the L-arginine nitric oxide pathway in hypoxic fetoplacental vasoconstriction. AB - The role of nitric oxide in hypoxic fetoplacental vasoconstriction (HFPV) was investigated using dually perfused human placental cotyledons. Standard medium (Earle's salt solution with added dextran and L-arginine) was equilibrated with 95 per cent O2 and 5 per cent CO2 (maternal side) and 94 per cent N2 and 6 per cent CO2 (fetal side). Part 1 consisted of perfusion for 1 h, then maternal perfusate equilibrated with a 95 per cent N2 and 5 per cent CO2 for 20 min (hypoxia), and then the original perfusion conditions resumed for 40 min. In part 2, this sequence was repeated with standard medium alone (n = 6), or with added N nitro-L-arginine methyl ester (L-NAME) (n = 6), or L-NAME and nitroglycerin (n = 6). When standard medium was used throughout, basal fetal perfusion pressure (30 +/- 2 mmHg) and the hypoxia-induced increase in perfusion pressure (18 +/- 1 mmHg) did not change significantly between parts 1 and 2. L-NAME increased basal perfusion pressure from 33 +/- 3 to 56 +/- 2 mmHg whereas perfusion pressure remained unchanged with L-NAME and nitroglycerin or nitroglycerin alone. The hypoxic vasoconstriction observed during part 1 in the L-NAME (14 +/- 3 mmHg) and the L-NAME with nitroglycerin groups (18 +/- 2 mmHg) was abolished during part 2 (to - 4 +/- 1 and 0.4 +/- 0.5 mmHg, respectively) whereas nitroglycerin alone significantly blunted the response (21 +/- 3 to 6 +/- 1 mmHg). Results suggest that a reduction in basal NO release mediates hypoxic fetoplacental vasoconstriction in the perfused human placental cotyledon in vitro. PMID- 9364598 TI - Long-chain polyunsaturated fatty acid transport across the perfused human placenta. AB - The role of the placenta in controlling the supply of fatty acids to the fetus was investigated in term placentae (n = 9) from normal pregnancies. The maternal side was perfused ex vivo for 90 min with a modified Krebs Ringer solution containing a physiological mixture of fatty acids and ratio of fatty acid to human albumin. There was no evidence of chain elongation and desaturation of the essential fatty acids. Relative to the value for oleic acid, the rate of transfer to the fetal circulation was: 1.30 +/- 0.02 (P < 0.001) for linoleic acid, 1.61 +/- 0.09 (P = 0.002) for alpha-linolenic acid, 0.67 +/- 0.10 (P = 0.033) for arachidonic acid and 2.10 +/- 0.16 (P = 0.003) for docosahexaenoic acid. For tissue accumulation the values were 1.47 +/- 0.39 (P < 0.001) for linoleic acid, 2.24 +/- 0.37 (P = 0.027) for alpha-linolenic acid, 9.84 +/- 1.03 (P = 0.001) for arachidonic acid, and 3.01 +/- 0.79 (P = 0.064) for docosahexaenoic acid. The order of selectivity for transfer from the maternal to the fetal circulation was docosahexaenoic > alpha-linolenic > linoleic > oleic > arachidonic acid. Such a mechanism would allow the preferential transfer of docosahexaenoic acid and the essential fatty acids to the fetal circulation, thereby protecting the polyunsaturated fatty acid supply to the fetus during a critical period of development. PMID- 9364599 TI - Demonstration of system y+L activity on the basal plasma membrane surface of rat placenta and developmentally regulated expression of 4F2HC mRNA. AB - Na(+)-independent cationic amino acid transport in the rat placenta occurs by leucine-sensitive and leucine-insensitive pathways. The ontogeny of these transport mechanisms within the rat placenta has been described recently. To assign the leucine-inhibitable portion of uptake definitively the uptake of [3H]arginine was studied in the presence of both BCH (to inhibit system Bo,+) and varied concentrations of leucine. Uptake of arginine into basal-enriched membrane vesicles derived from rat placenta was, in the presence of sodium, inhibited by micromolar concentrations of leucine, consistent with assignment of this activity to system y+L. In contrast, the majority of arginine uptake into apical-enriched membrane vesicles was leucine insensitive. Messenger RNA derived from rat placenta at days 14, 16, 18 and 20 of gestation was hybridized with full-length rat cDNA probes against NBAT and 4F2HC (thought to encode proteins associated with system bo,+ and y+L activities, respectively). No NBAT mRNA was detected, whereas 4F2HC mRNA was present at all gestational stages, increasing 12-fold over the last third of gestation. It is concluded that system y+L is present in the basal plasma membrane of the rat placenta syncytium and is subject to developmental regulation by a mechanism that alters the steady content of 4F2HC mRNA. PMID- 9364600 TI - Identification of two leucine-sensitive lysine transport activities in human placental basal membrane. AB - The recent demonstration of multiple high-affinity leucine-sensitive cationic transport systems prompted this investigation of their role in lysine uptake in basal cell membrane. Transport of lysine by basal membrane was saturable at both 22 and 37 degrees C and linear in time to 1 min and 30 sec, respectively. At 22 degrees C, at least two systems were active. The portion of uptake inhibited by the sulphydryl binding reagent N-ethylmaleimide (NEM) but not by leucine in the absence of sodium had a high K(m) and high Vmax and was attributed to system y+. NEM-insensitive uptake was fitted by a one-system model with K(m) (+/- s.e.) of 4 +/- 1 microM and a Vmax of 0.9 +/- 0.1 pmol/mg protein/min. This component was completely inhibited by leucine in the absence of sodium but not by glutamine in the presence of sodium. Therefore, it was attributed to system bo,+. At 37 degrees C, at least three systems were active. For essentially the same reasons as above the NEM inhibitable uptake was attributed to system y+. NEM-insensitive uptake was fitted by a one-system model with K(m) of 26 +/- 7 microM and Vmax of 11.1 +/- 2.8 pmol/mg protein/30 sec. Inhibition studies, however, indicated its heterogeneity. NEM-insensitive saturable uptake was only partially inhibited by either leucine in the absence of sodium (system bo,+) or by glutamine in the presence of sodium (system y+L). It is concluded that the NEM-insensitive portion of lysine uptake at 37 degrees C represents activity of both system bo,+ and the temperature-sensitive system y+L. As a previous investigation indicates, only one of these (system y+L) is present in the more specialized microvillous membrane. The demonstration of functional differences in the high affinity leucine transporters of basal and microvillous membrane in this and our previous investigations suggest that the two membranes possess different transport or modifier proteins. PMID- 9364602 TI - Distribution of cells bearing the HNK-1 epitope in the human placenta. AB - HNK-1 (Leu-7 antigen or CD57) is a unique carbohydrate moiety found in certain glycosphingolipids and several cell adhesion glycoproteins on the cell membrane. Previous studies have suggested that HNK-1 carbohydrates act as adhesive ligands in cell-cell interactions. Using a monoclonal antibody reactive to the HNK-1 moiety and an immunoperoxidase method on formalin-fixed paraffin-embedded tissue, the expression of the HNK-1 epitope in human placentae was confined to the intermediate trophoblast (IT) in trophoblastic columns. The number of HNK-1 immunoreactive IT cells increased from the proximal to the midportion of the trophoblastic column, and then disappeared at the junction of the column with the basal plate where IT infiltrates the endomyometrium and becomes extravillous IT. Neither cytotrophoblast nor syncytiotrophoblast reacted with the HNK-1 antibody. In hydatidiform moles, HNK-1 immunoreactivity was localized to areas that structurally resembled trophoblastic columns. In contrast, placental site trophoblastic tumours which do not contain structures analogous to trophoblastic columns did not express HNK-1 epitope. Expression of HNK-1 was only rarely observed in choriocarcinomas, being present in less than 5 per cent of trophoblastic cells in two of 13 cases. The murine placenta, which lacks trophoblastic columns, was negative for HNK-1. Thin-layer chromatography immunostaining demonstrated the HNK-1 reactive glycosphingolipids in placental lipid extracts, whereas Western blot analysis from placental protein extract failed to reveal detectable glycoproteins that demonstrated HNK-1 immunoreactivity. In conclusion, the specific localization of HNK-1 reactive glycosphingolipids in trophoblastic columns of the human placenta suggests that the HNK-1 moiety may play an important role in maintaining cohesion between intermediate trophoblastic cells in the trophoblastic columns thereby contributing to the structural integrity of the villi that anchor the placenta to the basal plate. PMID- 9364603 TI - Quantitative analysis throughout pregnancy of intraepithelial large granular and non-granular lymphocyte distributions in the synepitheliochorial placenta of the cow. AB - Intraepithelial lymphocytes are a constant feature of ruminant uterine epithelium. Light microscope quantitation on semithin sections of resin embedded perfused material from pregnant and non-pregnant cows shows that although the proportion of large granular lymphocytes to non-granular lymphocytes in interplacentomal areas increases during pregnancy, the total number of lymphocytes in these areas remains at a similar level. However all types of lymphocytes are eliminated from the caruncular uterine epithelium of the cow by 28 days of pregnancy at the initiation of placentomal development. Despite the subsequent enormous growth in area of this region during pregnancy, no lymphocytes are found in the bovine placentomal cellular uterine epithelium. This pattern is similar to that in the ewe and goat although in these species the placentomal uterine epithelium is modified to maternofetal hybrid syncytial plaques. However, in the deer, a similar cellular placentomal epithelium has numerous intraepithelial lymphocytes and large granular lymphocytes are closely associated with fetomaternal hybrid trinucleate cells formed by binucleate cell migration throughout pregnancy. Cow interplacentomal large granular lymphocytes and trinucleate cells show similar apposition but the formation and fate of cow placentomal trinucleate cells does not involve lymphocytes. Since the caruncular (placentomal) area is 10-20 times that of the intercaruncular this suggests a very different function for intraepithelial lymphocytes in the deer compared with the other ruminant species. PMID- 9364601 TI - Vascular endothelial growth factor, placenta growth factor and their receptors in isolated human trophoblast. AB - The expression of the angiogenic growth factors, vascular endothelial cell growth factor (VEGF) and placenta growth factor (PIGF) was demonstrated in isolated human term cytotrophoblast and in vitro differentiated syncytiotrophoblast. RNase protection assays demonstrated VEGF expression in both cytotrophoblast and syncytiotrophoblast while prominent PIGF expression was detected in both types of trophoblast by Northern blot analyses. VEGF expression increased approximately eightfold in trophoblast cultured under hypoxic conditions (1 per cent O2) yet PIGF expression decreased 73 +/- 5.5 per cent in the same trophoblast. These results suggest distinct regulatory mechanisms govern expression of VEGF and PIGF in trophoblast. Characterization of the VEGF/PIGF receptors, KDR and flt-1, revealed the presence of flt-1 mRNA in isolated cytotrophoblast and in vitro differentiated syncytiotrophoblast. KDR was not detected in the isolated trophoblast. Exogenous rhVEGF induced c-Jun N-terminal kinase (JNK) activity in the normal trophoblast indicating that the flt-1 receptors on trophoblast are functional. Trophoblast-derived VEGF/PIGF could act in a paracrine fashion to promote uterine angiogenesis and vascular permeability within the placental bed. In addition, presence of function flt-1 on normal trophoblast suggests that VEGF/PIGF functions in an autocrine manner to perform an as yet undefined role in trophoblast invasion, differentiation, and/or metabolic activity during placentation. PMID- 9364604 TI - Activity of 72-kDa and 92-kDa matrix metalloproteinases in placental tissues of cows with and without retained fetal membranes. AB - This study compared the activity of matrix metalloproteinases (MMP-2 and MMP-9) in retained and non-retained bovine placenta. The activities of MMPs and their zymogens were measured in fetal and maternal placental tissues from control cows (group B) and animals affected with retention of fetal membranes (group A) using a zymography technique on 10 per cent SDS polyacrylamide gels. The activity of proMMP-9 detected only in the maternal part of the placenta was lower in group A than in group B. ProMMP-2 activity was higher in group A than in group B in both tissues. The active forms of MMP-2 were observed in the maternal and fetal part of placenta in group B, but only the 68-kDa form was detected in the placental tissues of group A. The differences in enzyme activity between the groups and the lack of 64- and 60-kDa active forms of MMP-2 in the maternal and fetal parts of the retained placenta may have influenced the hydrolysis of collagen and the proper release of fetal membranes. PMID- 9364605 TI - Environmental pollutants as aetiological agents in female reproductive pathology: placental glycan expression in normal and polychlorinated biphenyl (PCB)-exposed mink (Mustela vison). AB - Polychlorinated biphenyls (PCB) may cause growth retardation or fetal death in mink. Pathological changes in endotheliochorial mink placentae were examined following exposure to PCB during gestation. Placentae from six animals with average fetal crown-rump (C-R) lengths between 16 and 53 mm given 0.65 mg/day Clophen A50 (low dose), and one from five animals with an average fetal C-R length of 14 mm given 1.3 mg/day (high dose), were examined. Mink were treated from 9 to 24 days before mating until killed at day 53. Placentae were formalin fixed with four size-matched controls and embedded in resin. Sections were stained with five biotinylated lectins to detect specific glycans. Both control and treated (low dose) mink showed degenerative changes in maternal endothelium from 13-16 mm, revealed by increased lectin binding, caused probably by high cell turnover during tissue remodelling. Controls of 47 and 50 mm exhibited fewer degenerate maternal endothelial cells. The 31-mm PCB-treated tissue showed separation of the trophoblast from the interstitial layer and, at 53 mm, loss of its normal architecture, increased damage to maternal endothelium and infarction. High-dose PCB was extremely toxic, producing fetal death or extensive placental infarction by 14 mm C-R length. Lectin staining thus revealed the effects of PCB toxicity, shown by increased injury to maternal endothelium and severe trophoblastic damage. PMID- 9364606 TI - Perinatal features associated with placental mesenchymal dysplasia. AB - Six new cases of placental mesenchymal dysplasia are presented and the findings compared to those reported in 16 similar cases published in the literature. Mesenchymal dysplasia was suspected when a placental scan showed a partial mole with a fetus of normal size and normal karyotype. Three fetuses of this series and nine out of 18 cases from the literature review also presented with Beckwith Wiedemann syndrome features. This placental anomaly is more commonly associated with a 46,XX karyotype. Comparable placental histopathological features in cases of mesenchymal dysplasia with or without congenital anomalies diagnostic of Beckwith-Wiedemann syndrome suggest that in some of these cases the overgrowth of specific fetal tissue is limited to the placenta and the fetus remains unaffected. Histological similarity between mesenchymal dysplasia and cellular chorioangioma suggests a common embryologic origin for both these placental abnormalities. Ultrasound/Doppler serial investigations indicate that the circulatory imbalance is due to hypovascularization of the dysplastic lobules, found in mesenchymal dysplasia. This induces the progressive aneurysmal and varicose dilatation of chorionic vessels, however, these anatomical transformations are not associated with a change in resistance to flow in both uterine and umbilical circulations nor with an excess of obstetrical complication when the fetus is anatomically normal. PMID- 9364607 TI - Lipoprotein lipase, LDL receptors and apo-lipoproteins in human fetal membranes at term. AB - Ultrastructurally, all cells of human fetal membranes strongly exhibit a large amount of lipid deposits throughout pregnancy. Their origin and function is still unknown. The aim of this study was to investigate the localization of key components of lipid metabolism in this tissue. Using immunohistochemical techniques, the distribution of lipoprotein lipase (LPL), low density lipoprotein receptors (LDL receptors), and apo-lipoprotein B and E was investigated in 20 human fetal membranes at term. In addition, electron microscopy was used to study the intracellular localization of lipoprotein-sized particles. Amnionic epithelium and trophoblast cells reacted strongly for LPL. LDL receptors and apo lipoproteins were present in amnionic epithelium and fibroblasts of the amnion. In none of the investigated cells were lipoprotein-sized particles identified. Similar results were obtained in all 20 cases. The findings indicate that lipoprotein from the amniotic fluid or from the maternal circulation may serve as substrate for lipids in human fetal membranes. PMID- 9364609 TI - Increased xanthine oxidase during labour--implications for oxidative stress. AB - Xanthine dehydrogenase/oxidase (XDH/XO) produces uric acid. When in the oxidase form, this production is coupled with the generation of free radicals. Hypoxia reperfusion enhances conversion of XDH to XO. Since the placenta is exposed to short periods of hypoxia reperfusion during labour, 17 placentae of pregnancy terminated by elective caesarean section and five placentae of pregnancies terminated by caesarean section during labour were examined for XDH/XO activity. It was found that XO activity was higher in the placentae of labouring women (P = 0.003), which suggests that labour enhances conversion of XDH to XO, facilitating free radical production. PMID- 9364608 TI - The interleukin-1 system in gestational tissues at term: effect of labour. AB - Previous studies suggest that the interleukin-1 (IL-1) system is involved in preterm labour, at least in cases associated with intrauterine infection. To investigate the effect of term labour without infection on the IL-1 system, the messenger ribonucleic acid (mRNA) expression of IL-1 beta, IL-1 receptor type I (IL-1R tI), IL-1 receptor antagonist (IL-1ra), and IL-1 beta converting enzyme (ICE) were examined by Northern blot analysis and by reverse transcriptase polymerase chain reaction (RT-PCR) in paired samples of decidua and placenta obtained from women having spontaneous vaginal delivery (group 1) or elective caesarean section (group 2) at term. In addition, concentrations of IL-1 beta and IL-1ra proteins were measured by ELISA in paired decidual and placental cytosols. In all decidual samples, IL-1 beta mRNA was expressed strongly, and the IL-1 beta concentration was 40- to 50-fold higher than in paired placental samples, in which the signal for IL-1 beta mRNA could be detected by RT-PCR only, and the amount of IL-1 beta protein was undetectable or very low. A comparison between the study groups revealed that the decidual IL-1 beta mRNA level tended to be higher in group 1, and the median IL-1 beta concentration in decidual cytosols was significantly higher in group 1 than in group 2 (P < 0.05). The IL-1R tI mRNA transcript was stronger in decidual than in paired placental samples in both groups. The mRNAs encoding ICE and IL-1ra were detected by RT-PCR in decidual and placental samples from both groups. The IL-1ra concentration tended to be higher in decidual cytosols than in paired placental cytosols, but there was no difference between the study groups. The IL-1ra/IL-1 beta ratio was significantly lower in decidual samples in women with spontaneous labour than in women without labour (P < 0.05). The results of this study confirm that decidua is the major site of IL-1 beta production and action in term gestational tissues. Furthermore, the results show that the major change in decidual/placental IL-1 system during parturition is the increase in decidual IL-1 beta production. Whether the increased IL-1 beta production precedes or is a consequence of labour, remains still unclear. PMID- 9364610 TI - The brain as a symbol-processing machine. AB - The knowledge accumulated about the biochemistry of the synapsis in the last decades completely changes the notion of brain processing founded exclusively over an electrical mechanism, toward that supported by a complex chemical message exchange occurring both locally, at the synaptic site, as well as at other localities, depending on the solubility of the involved chemical substances in the extracellular compartment. These biochemical transactions support a rich symbolic processing of the information both encoded by the genes and provided by actual data collected from the surrounding environment, by means of either special molecular or cellular receptor systems. In this processing, molecules play the role of symbols and chemical affinity shared by them specifies the syntax for symbol manipulation in order to process and to produce chemical messages. In this context, neurons are conceived as message-exchanging agents. Chemical strings are produced and stored at defined places, and ionic currents are used to speed up message delivery. Synaptic transactions can no longer be assumed to correspond to a simple process of propagating numbers powered by a factor measuring the presynaptic capacity to influence the postsynaptic electrical activity, but they must be modeled by more powerful formal tools supporting both numerical and symbolic calculations. It is proposed here that formal language theory is the adequate mathematical tool to handle such symbolic processing. The purpose of the present review is therefore: (a) to discuss the relevant and recent literature about trophic factors, signal transduction mechanisms, neuromodulators and neurotransmitters in order (b) to point out the common features of these correlated processes; and (c) to show how they may be organized into a formal model supported by the theory of fuzzy formal languages (d) to model the brain as a distributed intelligent problem solver. PMID- 9364611 TI - Human neuronal nicotinic receptors. AB - Nicotine is a very widely used drug of abuse, which exerts a number of neurovegetative, behavioural and psychological effects by interacting with neuronal nicotinic acetylcholine receptors (NAChRs). These receptors are distributed widely in human brain and ganglia, and form a family of ACh-gated ion channels of different subtypes, each of which has a specific pharmacology and physiology. As human NAChRs have been implicated in a number of human central nervous system disorders (including the neurodegenerative Alzheimer's disease, schizophrenia and epilepsy), they are suitable potential targets for rational drug therapy. Much of our current knowledge about the structure and function of NAChRs comes from studies carried out in other species, such as rodents and chicks, and information concerning human nicotinic receptors is still incomplete and scattered in the literature. Nevertheless, it is already evident that there are a number of differences in the anatomical distribution, physiology, pharmacology, and expression regulation of certain subtypes between the nicotinic systems of humans and other species. This review will attempt to survey the major achievements reached in the study of the structure and function of NAChRs by examining the molecular basis of their functional diversity viewed mainly from pharmacological and biochemical perspectives. It will also summarize our current knowledge concerning the structure and function of the NAChRs expressed by other species, and the newly discovered drugs used to classify their numerous subtypes. Finally, the role of NAChRs in behaviour and pathology will be considered. PMID- 9364612 TI - Animal models of intractable epilepsy. AB - Twenty to 30% of patients with epilepsy develop chronic or intractable epilepsy, i.e. the seizures persist despite accurate diagnosis and carefully monitored treatment with antiepileptic drugs. It is still not known why and how epilepsy becomes an intractable disorder in such patients, while other patients with seemingly identical seizure types can achieve control of seizures with medication. Experimental epilepsy research has generated new neurophysiological, neurochemical and neuropharmacological approaches but is still hampered by a lack of adequate experimental models of chronic intractable epilepsy. An animal model of epilepsy allowing selection of pharmacoresistant and pharmacosensitive subgroups of animals would be a valuable tool to study mechanisms of intractability and to develop more effective treatment strategies. This review concentrates on identifying animal models that mimic patterns of pharmacological resistance in humans with epilepsy. Two models seem to be interesting in this regard, epileptic dogs with different types of spontaneous recurrent seizures and amygdala-kindled rats. In both models, animals which do not respond to repeated or chronic administration of antiepileptic drugs (non-responders) can be separated from animals in whom antiepileptics are effective (responders). Unfortunately, the dog model has several inherent logistical problems, whereas pharmacoresistant subgroups of kindled rats offer a unique tool to study why seizures become intractable, particularly because pathophysiologically processes in these resistant rats can be compared directly with those of kindled rats which respond to treatment. Furthermore, the new rat model can be used to identify predictors of intractability during onset of treatment with an antiepileptic drug and is a valuable addendum to the battery of animal models used in preclinical evaluation of novel drugs. In addition to pharmacoresistant epileptic dogs and kindled rats, several other potential models of intractable epilepsy are described to stimulate and outline areas for future research. PMID- 9364613 TI - GABA-ergic transmission in deep cerebellar nuclei. AB - gamma-Aminobutyric acid (GABA) is the inhibitory transmitter released at Purkinje cell axon terminals in deep cerebellar nuclei (DCN). Neurons in DCN also receive excitatory glutamatergic inputs from the inferior olive. The output of DCN neurons, which depends on the balance between excitation and inhibition on these cells, is involved in cerebellar control of motor coordination. Plasticity of synaptic transmission observed in other areas of the mammalian central nervous system (CNS) has received wide attention. If GABA-ergic and/or glutamatergic synapses in DCN also undergo plasticity, it would have major implications for cerebellar function. In this review, literature evidence for GABA-ergic synaptic transmission in DCN as well as its plasticity are discussed. Studies indicate that fast inhibitory postsynaptic potentials (IPSPs) and currents (IPSCs) in neurons of DCN are mediated by GABAA receptors. While GABAB receptors are present in DCN, they do not appear to be activated by Purkinje cell axons. The IPSPs undergo paired-pulse, as well as frequency-dependent, depressions. In addition, tetanic stimulation of inputs can induce a long-term depression (LTD) of the IPSPs and IPSCs. Excitatory synapses do not appear to undergo long-term potentiation or LTD. The LTD of the IPSP is not input-specific, as it can be induced heterosynaptically and is associated with a reduced response of DCN neurons to a GABAA receptor agonist. Postsynaptic Ca2+ and protein phosphatases appear to contribute to the LTD. The N-methyl-D-aspartate receptor-gated, as well as the voltage-gated Ca2+ channels are proposed to be sources of the Ca2+. It is suggested that LTD of GABA-ergic transmission, by regulating DCN output, can modulate cerebellar function. PMID- 9364614 TI - Syncytial integration by a network of coupled bipolar cells in the retina. AB - A model system for syncytial integration is the outer vertebrate retina, where graded signals or electrotonic potentials interact laterally via gap junctions to form an integrated response that is relayed by chemical synapses to the next layer of interconnected cells. Morphological and physiological experiments confirm that bipolar cells form quasisyncytial lattices, and so this review will aim to address two important issues: the function of coupling in visual information processing and the construction of a robust mathematical model that can adequately simulate signal spread in the bipolar cell syncytium. It is shown that the role of coupling in bipolar cells differs from that associated in the presynaptic networks, namely, loss in spatial resolution in order to increase the signal-to-noise ratio. The intrinsic membrane properties of bipolar cells which give rise to voltage-dependent currents are inactive over the normal in vivo operating range of membrane potential and may be shunted as a direct result of electrotonic coupling, suppressing any possibility of action potential propagation in the bipolar cell syncytium. It is therefore speculated that the mechanisms underlying processing of information in bipolar networks are dependent on the structure of bipolar cells and in particular, on the presence of gap junctions. It is proposed that a three-dimensional model which incorporates the spatial properties of each bipolar cell in the network in the form of a leaky cable is the most likely model to simulate signal spread in the bipolar cell syncytium in vivo. This is because discrete network models represent each bipolar cell in the syncytium as isopotential units without any spatial structure, and thus are unable to reproduce the temporal characteristics of electrotonic potential spread within the central receptive field of bipolar cells. PMID- 9364615 TI - Slow eye movements. AB - Monkeys and humans are able to perform different types of slow eye movements. The analysis of the eye movement parameters, as well as the investigation of the neuronal activity underlying the execution of slow eye movements, offer an excellent opportunity to study higher brain functions such as motion processing, sensorimotor integration, and predictive mechanisms as well as neuronal plasticity and motor learning. As an example, since there exists a tight connection between the execution of slow eye movements and the processing of any kind of motion, these eye movements can be used as a biological, behavioural probe for the neuronal processing of motion. Global visual motion elicits optokinetic nystagmus, acting as a visual gaze stabilization system. The underlying neuronal substrate consists mainly of the cortico-pretecto-olivo cerebellar pathway. Additionally, another gaze stabilization system depends on the vestibular input known as the vestibulo-ocular reflex. The interactions between the visual and vestibular stabilization system are essential to fulfil the plasticity of the vestibulo-ocular reflex representing a simple form of learning. Local visual motion is a necessary prerequisite for the execution of smooth pursuit eye movements which depend on the cortico-pontino-cerebellar pathway. In the wake of saccades, short-latency eye movements can be elicited by brief movements of the visual scene. Finally, eye movements directed to objects in different planes of depth consist of slow movements also. Although there is some overlap in the neuronal substrates underlying these different types of slow eye movements, there are brain areas whose activity can be associated exclusively with the execution of a special type of slow eye movement. PMID- 9364616 TI - Mechanical responses of the mammalian cochlea. AB - Recent findings in auditory research have significantly changed our views of the processes involved in hearing. Novel techniques and new approaches to investigate the mammalian cochlea have expanded our knowledge about the mechanical events occurring at physiologically relevant stimulus intensities. Experiments performed in the apical, low-frequency regions demonstrate that although there is a change in the mechanical responses along the cochlea, the fundamental characteristics are similar across the frequency range. The mechanical responses to sound stimulation exhibit tuning properties comparable to those measured intracellularly or from nerve fibres. Non-linearities in the mechanical responses have now clearly been observed at all cochlear locations. The mechanics of the cochlea are vulnerable, and dramatic changes are seen especially when the sensory hair cells are affected, for example, following acoustic overstimulation or exposure to ototoxic compounds such as furosemide. The results suggest that there is a sharply tuned and vulnerable response related to the hair cells, superimposed on a more robust, broadly tuned response. Studies of the micromechanical behaviour down to the cellular level have demonstrated significant differences radially across the hearing organ and have provided new information on the important mechanical interactions with the tectorial membrane. There is now ample evidence of reverse transduction in the auditory periphery, i.e. the cochlea does not only receive and detect mechanical stimuli but can itself produce mechanical motion. Hence, it has been shown that electrical stimulation elicits motion within the cochlea very similar to that evoked by sound. In addition, the presence of acoustically-evoked displacements of the hearing organ have now been demonstrated by several laboratories. PMID- 9364617 TI - Regeneration in the developing optic nerve: correlating observations in the opossum to other mammalian systems. AB - Regeneration of severed axons within the central nervous system of adult mammals does not normally occur with any degree of success. During development, however, newly forming projections must send axons to distant sites and form appropriate connections with their targets: successful regeneration has been observed during this critical period. The opossum central nervous system develops during early postnatal life and has provided a useful experimental model to investigate this specialized mode of axonal regeneration in mammals. The presence of a clear decision point at the optic chiasm has also provided a useful site at which to investigate the navigational capacity of retinal ganglion cells regenerating along the optic nerve during this critical period. Regeneration failure occurs as the central nervous system progresses from this permissive, developing state to a mature, non-permissive adult state. Studies into the behaviour of glial and neuronal elements around this transition period can help elucidate some of the factors that need to be overcome if regeneration is ever to become successful in adult mammals. The regeneration characteristics of a lesioned projection are dependent upon its developmental stage and are also related to the proximity of axotomy along its pathway. A system of staging is proposed to correlate observations in the opossum optic nerve to other mammalian systems. PMID- 9364618 TI - Verbal memory after three months of intranasal vasopressin in healthy old humans. AB - In animals, evidence has been accumulated that vasopressin (VP) improves learning and memory. In humans, this effect was not consistently demonstrated, and attempts to restore age-related memory deficits by VP also remained inconsistent. Assuming that in old subjects a beneficial effect on memory occurs only after prolonged treatment with VP, we conducted a study in 26 healthy elderly persons receiving 40 IU of VP for three months through the intranasal route. The trial was randomized, placebo-controlled and held double-blind. Memory was assessed by the Auditory Verbal Learning Test (AVLT) requiring the subject to learn repeatedly presented lists of 15 words. Results demonstrated no general effect of long-term treatment with VP on memory in aged humans. However, recall of an interfering word list was improved, indicating a diminished proactive interference by the peptide. Additionally, VP influenced recall depending on the serial position of an item: it improved the primacy effect (i.e. recall of the first words of a list) and impaired the recency effect. This result may indicate an improved semantic encoding (i.e. a primary effect on processes of attention) after long-term administration of VP. PMID- 9364619 TI - Effects of psychological stress on serum immunoglobulin, complement and acute phase protein concentrations in normal volunteers. AB - The aim of this study was to examine the effects of academic examination stress on serum immunoglobulins (Igs), i.e. IgA, IgG, IgM, complement factors, i.e. C3c and C4, and acute phase proteins, i.e. alpha 1-acid glycoprotein (alpha 1-S), haptoglobin (Hp) and alpha 2-macroglobulin (alpha 2-M). Thirty-seven university students participated in this study. Serum was sampled a few weeks before and after as well as one day before a difficult academic examination. On the same occasions, students completed the Perceived Stress Scale (PSS). Students were divided into two groups, i.e. those with high- and low-stress perception as defined by changes in the PSS score. Academic examination stress induced significant increases in serum IgA, IgG, IgM, and alpha 2-M in students with high stress perception, but not in these with low-stress perception. The stress induced changes in serum IgA, C3c, and alpha 1-S concentrations were significantly higher in students with high-stress perception than in those with a low-stress perception. The stress-induced changes in serum IgA, IgM, C3c, C4, alpha 1-S, Hp and alpha 2-M were normalized a few weeks after the stress condition, whereas IgG showed a trend toward normalization. There were significant positive relationships between the stress-induced changes in the PSS and serum IgA, IgG, IgM and alpha 2-M. These findings suggest that psychological stress is accompanied by an altered secretion of serum Igs, complement factors and some acute phase proteins. PMID- 9364620 TI - Effects of stress and glucocorticoids on CNS oxytocin receptor binding. AB - Oxytocin receptors in several regions of the limbic system are regulated by gonadal steroids and play an important role in the mediation of maternal, sexual and affiliative behaviors. We have previously reported oxytocin receptor regulation by glucocorticoids in hippocampus and subiculum-neuroanatomical regions implicated in memory and stress regulation. In the current study we examined oxytocin receptor regulation by stress and high glucocorticoid concentration in adrenally intact male rats. Single prolonged stress and chronic non-habituating stress were used as experimental conditions in the first study, and chronic non-habituating and high dose corticosterone implants in the second. Oxytocin receptor concentration was assessed using in vitro receptor autoradiography with [125I]OVTA at the approximate KD concentration. Both stress paradigms increased oxytocin receptor binding (F = 3.7, df = 2, p = .03) across brain regions in the first study. Chronic non-habituating stress and corticosterone implants increased oxytocin receptor binding in the ventral hippocampus only (one-way ANOVA, F = 3.88, df = 2, p < .05). The current studies demonstrate that stress increases oxytocin receptor binding in areas of the CNS that are rich in glucocorticoid receptors, such as hippocampus. This suggests differential regulation of oxytocin receptors in CNS, depending upon their functional role in different regions. Oxytocin receptor modulation could mediate some of the long-term effects of stress on memory, and possibly play a role in the regulation of hypothalamo-pituitary-adrenal stress response. The ability of circulating glucocorticoids to up-regulate these receptors suggests a plausible mechanism for this stress-sensitive regulation. PMID- 9364621 TI - Psychological and physiological responses during an exam and their relation to personality characteristics. AB - The aim of the study was to compare emotional and physiological responses to real and control examinations and to assess their relation to personality characteristics. Emotional responses were assessed by state anxiety and perceived stress. The assessment of physiological responses included the activity of the cardiac system (heart periods, vagal tone), the adrenocortical system (cortisol) and the immune system (immune globulin A, sIgA). Emotional and physiological responses of 23 students (12 males, 11 females) were assessed during an oral exam at the end of a basic course in psychology which was a prerequisite for the students' final exams. For the control condition physiological responses were assessed one week before the examination during a memory test. The findings of the study demonstrate different emotional and physiological response patterns to examinations as compared to the control condition. Heightened anxiety was observed only before the exam. Whereas within-situation physiological responses (higher heart periods, cortisol, and sIgA; lower vagal tone) were observed both under the exam and control condition, responses to exam condition indicated pre exam anticipatory activation and post-exam restricted recovery responses. With regard to personality characteristics subjects with high ego-resiliency showed more flexible adaptation than subjects with low ego-resiliency both on the emotional level (anxiety down-regulation after exam) and on the physiological level (situation-specific responses, quick recovery). Subjects with high ego control exhibited a lower physiological reactivity under both conditions, i.e. they seemed to maintain longer their control also on a physiological level independent of the type of situation. PMID- 9364622 TI - Stress-restress: effects on ACTH and fast feedback. AB - Glucocorticoid secretion is tightly regulated by negative feedback. Glucocorticoid feedback has been found to be altered in depression and post traumatic stress disorder (PTSD). While hyposensitive glucocorticoid feedback has been found in depression, hypersensitive or enhanced negative feedback was described in PTSD. Enhanced negative feedback, can be seen as a sensitization of the inhibitory elements of HPA axis, and stress-restress or time dependent sensitization (TDS) model, has been suggested as an animal model for PTSD. We have studied the effects of this model on the HPA axis to determine whether it will produce increased sensitivity to negative feedback as found in PTSD patients. Adult Sprague-Dawley male rats were exposed to a single session of prolonged stress (restraint followed by a forced swim and exposure to ether vapors) and briefly restressed 7 days later. The effects of single prolonged stress on plasma ACTH and corticosterone responses (0, 5, and 30 min) and on glucocorticoid fast feedback (cortisol vs. saline pretreatment) were assessed in two studies. Animals exposed to single prolonged stress showed enhanced negative feedback in comparison to naive animals (F = 4.6371, df = 3, p = .0107), but there was no difference in ACTH or corticosterone responses during the restress. Pretreatment with cortisol, in the first stress session, did not prevent the development of the enhanced fast feedback when restressed. This can be seen as a sensitization of the inhibitory elements of HPA axis, suggesting that stress restress paradigm might serve as a good animal model for HPA abnormalities found in PTSD patients. PMID- 9364623 TI - 1996 Curt P. Richter Award. Effects of viral infection on corticosterone secretion and glucocorticoid receptor binding in immune tissues. AB - During an immune challenge it has been suggested that responding cells secrete cytokines which then stimulate the release of glucocorticoids. Glucocorticoids, in turn, are believed to bind to their receptors in target immune tissues and provide feedback inhibition on evolving immune responses. The foundations for this hypothesis have been drawn primarily from studies on animal models of autoimmune and/or inflammatory processes, and the relevance of these glucocorticoid-immune interactions to viral infections has not been extensively examined. Accordingly, we infected mice with lymphocytic choriomeningitis virus (LCMV) and measured plasma corticosterone and cytosolic glucocorticoid receptor (GR) binding at multiple time points throughout the day and throughout infection (days 3, 5, 7 and 10 post infection). Despite a vigorous immune response to this virus, LCMV infection was associated with minimal and transient increases in corticosterone secretion. Interestingly, however, significant decreases in cytosolic GR were found in immune tissues. Receptor decreases were characterized by a significant decrease in GR binding during the diurnal rise in corticosterone in the spleen and thymus of infected but not uninfected animals on days 5-10 post infection. In addition, in the morning on these days, GR binding in the spleen of infected mice was decreased compared to uninfected control mice. Following an acute injection of corticosterone on day 7 post infection, LCMV-infected animals exhibited a significantly greater decrease in splenic GR binding than uninfected control mice, suggesting an increased sensitivity to corticosterone in infected animals. No changes were found in the affinity (Kd) of the GR during infection, nor was there evidence of an infection-associated decrease in plasma corticosteroid binding globulin. The appearance of significant GR changes in the spleen and thymus, in the absence of significant elevations in corticosterone or decreases in its binding protein, suggests that cytokines and/or other factors produced within the immune tissues during infection either directly influenced GR number and/or function or influenced the local availability of corticosterone. Taken together, the results indicate that interactions between the neuroendocrine and immune systems can be modified at the level of the GR in the context of an ongoing immune response such as during a viral infection. PMID- 9364624 TI - Pulsed dose-rate brachytherapy. PMID- 9364625 TI - Postoperative radiotherapy of spinal and intracranial ependymomas: analysis of prognostic factors. AB - PURPOSE: Postoperative radiation therapy adds significantly to disease control and survival of patients with ependymoma. However, much controversy exists about the radiation treatment policy. We report the long-term results of a cohort of 56 patients with primary intracranial and spinal ependymomas. Special effort has been taken to define prognostic indicators as a basis for future treatment strategies. PATIENTS AND METHODS: Between November 1963 and May 1995, 56 patients with histological proven ependymoma were referred to our clinic for further treatment following surgery. Thirty patients had a high grading tumor and 26 had low grade tumors. Seventeen patients had supratentorial tumors and 24 had infratentorial tumors. Fifteen patients suffered from localized spinal tumors. RESULTS: The mean survival time for all patients was 77 months. Five- and 10-year survival probabilities were 60 and 51%, respectively. The mean progression free survival (PFS) probability for all patients was 67 months with corresponding 5- and 10-year PFS probabilities of 53 and 39%, respectively. On univariate analysis initial performance status, age and tumor grade were significant for survival probability. Concerning PFS radiation dose was significant with improved survival with doses > 45 Gy. On multivariate analysis, tumor grade and initial performance status proved to be the only independent prognostic factors. CONCLUSIONS: Tumor grade, age, initial performance status and radiation dose are significant factors for the clinical course of patients and have to be taken into account for the urgently needed prospective trials. PMID- 9364626 TI - Management of optic pathway and chiasmatic-hypothalamic gliomas in children with radiation therapy. AB - BACKGROUND AND PURPOSE: Optic pathway and chiasmatic-hypothalamic gliomas are rare childhood tumors. This study presents the experience in management of these tumors with radiation therapy. MATERIALS AND METHODS: Thirty-three children with the diagnosis of optic pathway and chiasmatic-hypothalamic gliomas were treated with radiation therapy from 1973 through 1994 in the Department of Radiation Oncology at Ankara University Faculty of Medicine. Twenty-four children had optic pathway gliomas and nine had chiasmatic-hypothalamic gliomas. Evidence of neurofibromatosis was present in six children. Subtotal resection was performed in 22 children and a biopsy in seven. The most common prescription for total tumor dose was 50 Gy, delivered in 2 Gy daily fractions. Follow-up ranged from 0.5 to 16.1 years (mean, 13.6 years). RESULTS: Overall, progression-free and cause-specific survival probabilities for the entire group were 93%, 82% and 93%, respectively, at 5 years and 79%, 77% and 88%, respectively, at 10 years. Differences in overall, progression-free and cause-specific survival probabilities between optic pathway and chiasmatic-hypothalamic gliomas were not statistically significant. Absence of evidence of neurofibromatosis correlated with significantly better progression-free and cause-specific survival probabilities. CONCLUSION: Radiation therapy is effective in stabilization or improvement of vision and prevention of tumor progression in both optic pathway and chiasmatic-hypothalamic gliomas. PMID- 9364627 TI - Accelerated radiotherapy for brain metastases. AB - BACKGROUND AND PURPOSE: Two novel fractionation schedules for whole-brain irradiation were applied to patients with brain metastases. Both schedules were aimed at reduction of treatment time, whereby tumour control should be increasing with the application of a higher total dose (schedule 2). MATERIALS AND METHODS: We applied 2 x 2.5 Gy/day to a total dose of 30 Gy (schedule 1) or 2 x 1.8 Gy/day to a total dose of 50.4 Gy (schedule 2). The interval between daily fractions was 6 h. Treatment was interrupted on weekends. The 30 Gy schedule was also used in adjuvant treatment for resected brain metastases. We compared the results of 15 patients who underwent the 50.4 Gy schedule and 47 patients who were treated up to 30 Gy with those of a historical patient group, treated with one daily fraction of 3 Gy up to 30 Gy (n = 283). RESULTS: Local result, clinical course and survival were similar for the 30 Gy groups, whereby prognostic factors were equally distributed. Despite a favourable patient selection no therapeutic gain was seen for the 50.4 Gy group. Patients treated with the accelerated 30 Gy schedule had a significantly worse progression-free survival and a higher rate of late radiation toxicity than the historical group. In contrast, no severe acute toxicity was observed. CONCLUSIONS: Considering progression-free survival and late toxicity, the accelerated 30 Gy schedule can not be recommended without hesitation. Radiotherapy with a higher total dose (50.4 Gy) showed no advantage. PMID- 9364628 TI - PDR brachytherapy with flexible implants for interstitial boost after breast conserving surgery and external beam radiation therapy. AB - BACKGROUND AND PURPOSE: For radiobiological reasons the new concept of pulsed dose rate (PDR) brachytherapy seems to be suitable to replace traditional CLDR brachytherapy with line sources. PDR brachytherapy using a stepping source seems to be particularly suitable for the interstitial boost of breast carcinoma after breast-conserving surgery and external beam irradiation since in these cases the exact adjustment of the active lengths is essential in order to prevent unwanted skin dose and consequential unfavorable cosmetic results. The purpose of this study was to assess the feasibility and morbidity of a PDR boost with flexible breast implants. MATERIALS AND METHODS: Sixty-five high risk patients were treated with an interstitial PDR boost. The criteria for an interstitial boost were positive margin or close margin, extensive intraductal component (EIC), intralymphatic extension, lobular carcinoma, T2 tumors and high nuclear grade (GIII). Dose calculation and specification were performed following the rules of the Paris system. The dose per pulse was 1 Gy. The pulse pauses were kept constant at 1 h. A geometrically optimized dose distribution was used for all patients. The treatment schedule was 50 Gy external beam to the whole breast and 20 Gy boost. PDR irradiations were carried out with a nominal 37 GBq 192-Ir source. RESULTS: The median follow-up was 30 months (minimum 12 months, maximum 54 months). Sixty percent of the patients judged their cosmetic result as excellent, 27% judged it as good, 11% judged it as fair and 2% judged it as poor. Eighty-six percent of the patients had no radiogenous skin changes in the boost area. In 11% of patients minimal punctiform telangiectasia appeared at single puncture sites. In 3% (2/65) of patients planar telangiectasia appeared on the medial side of the implant. The rate of isolated local recurrence was 1.5%. In most cases geometrical volume optimization (GVO) yields improved dose distributions with respect to homogeneity and compensation of underdosage at the margins of the implant. Only in 9% of patients was the dose distribution impaired by GVO. However, GVO causes a number of substantial changes of the dose distribution which have consequences for its application. CONCLUSIONS: The interstitial CLDR boost of the breast can be replaced by the PDR technique without severe acute and late complications and without deterioration of the cosmetic results. PMID- 9364629 TI - High dose rate endobronchial brachytherapy using a new applicator. AB - BACKGROUND AND PURPOSE: To obtain adequate spatial dose distribution for endobronchial brachytherapy, we applied reference dose points according to the bronchial diameter. For this purpose, we devised a new applicator of which the source transfer tube is contained in the center of the lumen for high dose rate (HDR) brachytherapy. MATERIALS AND METHODS: Thirty-nine patients with endobronchial cancer underwent endobronchial brachytherapy using an HDR afterloading machine with an Ir-192 source. In the nine patients treated with curative intent, treatment consisted of external beam radiotherapy with 40-60 Gy for 4-6 weeks and endobronchial brachytherapy with three fractions of 6 Gy. The 30 patients treated with palliative intent received one fraction of 10 Gy with or without external beam irradiation. The reference dose points were prescribed according to bronchial diameter, which was measured by the applicator's radiopaque wing expansion reflecting the bronchial caliber. RESULTS: The new applicator could be placed at the intended site in 37 lesions. Of 12 lesions which were treated with curative intent, eight (67%) disappeared after brachytherapy. The overall survival at 3 years of all patients and of the patients treated with curative intent was 22 and 64%, respectively. CONCLUSIONS: The source should be positioned in the center of the lumen; this technique is helpful in reducing side-effects caused by inhomogeneous dose distribution of endobronchial brachytherapy. PMID- 9364630 TI - Is pulsed dose rate more damaging to spinal cord of rats than continuous low dose rate? AB - BACKGROUND AND PURPOSE: Theoretical calculations suggest that pulsed dose-rate irradiation (PDR) should have approximately the same effectiveness as continuous low dose-rate (CLDR) when the same total dose is given in the same overall time, unless large doses per pulse (> 2 Gy) are used and/or non-exponential or very short half-times of repair (< 0.5 h) are present in the irradiated tissues. However, few animal experiments have been reported to test this theory, and some of them gave contradictory results. We have carried out experiments to determine whether PDR irradiation of 18 mm of cervical spinal cord in the rat was more or less effective than CLDR at 0.5-1 Gy/h, when the overall average dose rate during each day of PDR was close to the overall CLDR average dose rate. MATERIALS AND METHODS: PDR was simulated at a within-pulse dose rate of 4 Gy/h by filtered 18 MV X-rays from a linear accelerator. Two PDR schedules were used, 0.69 Gy at 1 h repetition (9 pulses per day) and 2 Gy at 3 h repetition (4 pulses per day), with overnight intervals of 16 and 15 h, respectively. The CLDR was delivered from iridium-192 wires in two concentric rings around a collar designed to fit the necks of rats so that they could eat and drink during the 72 h that was always the duration of the CLDR. Dose rate was then proportional to total CLDR dose. A range of doses was used to obtain dose response-curves, with a 15 Gy top-up dose (at 2 Gy/min, HDR) given on the day after the end of the PDR or CLDR irradiations. Animals were observed for at least 9 months to see whether fore limb myelopathy developed. A total of 6-8 rats was irradiated per dose point, in two sets of experiments at an interval of 12 months. RESULTS: A set of 2 Gy fractions (at HDR) given daily, followed by the same top-up dose of 15 Gy at HDR, was available from a previous experiment for planning. Its ED50 was 61.2 Gy. The ED50 values found for the PDR schedules with 2 Gy at 3 h and 0.69 Gy at 1 h were 59.9 and 60.2 Gy, respectively. These were just 2% more effective than the daily HDR fractions, similar to expectations from theory if two components of repair are present. However, the CLDR irradiations resulted in no myelopathy even after doses up to 68 Gy at 0.94 Gy/h.. Thus PDR over 7 days (not at nights) appears to be more effective than CLDR over 3 days, with an effective dose-modifying factor of at least 1.1 to 1.17. DISCUSSION AND CONCLUSIONS: Reasons for this absence of effect with CLDR in these experiments are discussed, the most likely explanation being that a substantial component of repair with very short T1/2 (< 0.5 h) was present in spinal cord of these rats. There is evidence from other experiments elsewhere and in our laboratory for such a fast component of repair. PMID- 9364631 TI - Dose reduction factors when increasing dose rate in LDR or MDR brachytherapy of carcinoma of the cervix. AB - BACKGROUND: The detailed summary of results from Bristol where 270 patients with carcinoma of the cervix were treated with either 75 cGy/h from manually loaded caesium or 150 cGy/h by remote afterloading (Newman, G. Increased morbidity following the introduction of remote afterloading, with increased dose rate, for cancer of the cervix. Radiother. Oncol. 39: 97-103, 1996) can be analysed to study the radiobiological factors that could have contributed to the different outcomes reported. The increases in grade 3 late complications from 4 to 22%, and in grade 2 + 3 from 12 to 32%, in spite of a reduction of 20% in dose, imply a rather large difference in biological effect between the two systems, which might or might not be due to dose rate differences. PURPOSE: The possibility that a significant part of the effect might have been due to the dose rate is investigated, with particular attention to what values of radiobiological parameters might explain it, or can be excluded. A similar set of clinical data from Tilsburg (Rodrigus, P., de Winter, K., Venselaar, J. and Leers, W.H. Evaluation of late morbidity in patients with carcinoma of the uterine cervix following a dose rate change. Radiother. Oncol. 42: 137-141, 1997), where dose rate was doubled from 54 to 107 cGy/h with a dose reduction of 20%, is also considered. METHODS: Linear quadratic modelling is employed to calculate Biologically Effective Doses (or ERDs) corresponding to the clinical protocols used. Repair of sublethal radiation damage at a range of half-times is assumed, both for mono- and bi-exponential components. When the LDR is doubled it is called MDR in the present study. RESULTS: The maximum ratios calculated for the BEDs of 16 Gy at MDR to 20 Gy at LDR were 1.06-1.15, assuming alpha/beta = 4-2 Gy, the latter being an unlikely extreme for rectal or urinary complications. These maxima occurred over a narrow range of t1/2 values from 1.5 to 2.5 h. If t1/2 were as long as 4-7 h or as short as 0.5-0.75 h, the biological effects would have been equal. The theoretically ideal dose reduction factors, calculated using the t1/2 values derived from the clinical data, are in the range of 24-29% instead of 20%. CONCLUSIONS: Somewhat greater dose reduction factors for late complications were suggested by this analysis than the 20% that has been commonly used when the dose rate is increased, both from the Bristol and Tilsburg data. The Bristol data showed no loss of therapeutic ratio on changing from manual to remote afterloading. Due to the close-to-optimum choice of the dose reduction factor which was actually used, some values for the half-time of repair of late complications in gynaecological brachytherapy could be estimated and used to calculate the theoretical dose reduction factors. PMID- 9364632 TI - Kinetics of repair in the spinal cord of the rat. AB - PURPOSE: Split dose experiments were carried out with two 2 Gy fractions per day at intervals ranging from 0.5 to 24 h, in order to investigate both the time to complete repair and the detailed kinetics of repair of sublethal damage in the cervical spine of rats. MATERIALS AND METHODS: Male rats of the WAG/Rij strain were irradiated at 2 Gy/min with 18 MV photons to a length of 18 mm of cervical spinal cord. Four hundred twenty-three rats were irradiated without top-up doses to investigate whether repair was complete by 24 h or whether any slow repair or proliferation occurred up to 50 days after irradiation. Three hundred seventy nine rats were also irradiated in split dose (2 Gy + delta t + 2 Gy each day) experiments, with intervals of 0.5, 1, 2, 4, 8 and 24 h. The split dose irradiations were followed by a single top-up dose of 15 Gy (producing about half the total damage). RESULTS: Repair was complete by 24 h as the ED50 values were the same at 1, 11 and 50 day intervals for two large fractions, and for 10 fractions in 10 or 50 days. A mono-exponential component of repair of T1/2 = 0.25 (95% CI 0.16-0.48) h was determined by direct analysis using all the data and T1/2 = 0.37 (0.28-0.53) h for the split 2 Gy doses with top-up only. A bi exponential analysis did not fit better. The presence of a second component was demonstrated graphically, with T1/2 of about 6.5 h but with a wide confidence interval from near 0 to 13 h. However, the 24 h ED50 was significantly different from all ED50s except the 8 h value. Considering all data together, an upper limit of about 7 h could be placed on any long component, or else repair could not be complete by 24 h. DISCUSSION AND CONCLUSIONS: Two components of repair (0.7 and 3.8 h) have been reported by Ang et al. (Ang, K.K., Jiang, G.L., Guttenberger, R., Thames, H.D., Stephens, L.C., Smith, C.D. and Feng, Y. Impact of spinal cord repair kinetics on the practice of altered fractionation schedules. Radiother. Oncol. 25: 287-294, 1992) in the spinal cord of Sprague Dawley rats. Two components have also been reported by others more recently. The present results could, with its graphical interpretation, agree in principle, but with a shorter fast component and a longer slow component. A slow component of 5.5 h was reported by Ruifrok et al. (Ruifrok, A.C.C., Kleiboer, B.J. and van der Kogel, A.J. Fractionation sensitivity of rat cervical spinal cord during radiation retreatment. Radiother. Oncol. 25: 295-300, 1992) in a related strain of WAG/Rij rats. The possible presence of a slower component than Ang et al.'s 3.8 h might help to explain the four myelopathies observed in the pilot studies for the CHART clinical trial. The presence of the definite fast component (< 0.5 h) could have important consequences when pulsed brachytherapy is used to replace continuous low dose rate irradiation. PMID- 9364633 TI - Potential advantages of protons over conventional radiation beams for paraspinal tumours. AB - BACKGROUND AND PURPOSE: Conformal treatment planning with megavoltage X-rays and protons was studied in an attempt to determine if there are advantage of boost therapy with protons instead of X-rays for a patient with a tumour growing around the cervical spinal cord. MATERIALS AND METHODS: A patient with a Ewing sarcoma was selected for the model study. The proton boost plan was realised with a six beam patched technique. Several X-ray boost techniques were planned, some not yet practically realisable. The techniques giving the best dose distributions and the best tumour control probabilities in the absence of significant late toxicity were looked for. The boost techniques were added to two large lateral X-ray beams covering the planning target volume (PTV) and the main risk organ, the spinal cord. The evaluation was made with two biological models, i.e. the tumour control probability (TCP) model, proposed by Webb and Nahum (Webb, S. and Nahum, A.E. A model for calculating tumour control probability in radiotherapy including the effect of inhomogeneous distributions of dose and clonogenic cell density. Phys. Med. Biol. 38: 653-666, 1993), and the normal tissue complication probability (NTCP) model, first derived by Lyman (Lyman, J.T. Complication probability as assessed from dose-volume histograms. Radiat. Res. 104: s13-s19, 1985). RESULTS: The comparison showed small but clear advantages of protons for the boost. At 1% NTCP in the spinal cord, the calculated TCP was on average 5% higher. However, depending on the values of the parameters chosen in the biological models, the gain for protons varied from 0-10%. The smallest gains were seen in radiosensitive tumours for which the TCP was close to 100% with any of the techniques and in radioresistant tumours for which neither technique resulted in any appreciable probability of local cure. CONCLUSION: Protons appear to have therapeutic advantages over conventional radiotherapy in tumours with relatively high radiosensitivity situated close to the spinal cord. PMID- 9364634 TI - Effect of geometrical optimization on the treatment volumes and the dose homogeneity of biplane interstitial brachytherapy implants. AB - BACKGROUND AND PURPOSE: The isodose distributions of HDR stepping source brachytherapy implants can be modified by changing dwell times and this procedure is called optimization. The purpose of this study is to evaluate the effect of geometrical optimization on the brachytherapy volumes and the dose homogeneity inside the implant and to compare them with non-optimized counterparts. MATERIAL AND METHODS: A set of biplane breast implants consisting of 84 different configurations have been digitized by the planning computer and volumetric analysis was performed for both non-optimized and geometrically optimized implants. Treated length (TL), treated volume (V100), irradiated volume (V50), overdose volume (V200) and quality index (QI) have been calculated for every non optimized implant and compared to its corresponding geometrically optimized implant having a similar configuration and covering the same target length. RESULTS: The mean TL was 74.48% of the active length (AL) for non-optimized implants and was 91.87% for optimized implants (P < 0.001). The mean QI was 1.83 for non-optimized implants and 2.17 for optimized implants (P < 0.001). The mean V50/V100 value was 2.71 for non-optimized implants and 2.65 for optimized implants (P < 0.001) and the mean V200/V100 value was 0.09 for non-optimized implants and 0.10 for optimized implants (P < 0.001). CONCLUSIONS: By performing geometrical optimization it is possible to implant shorter needles for a given tumour to adequately cover the target volume with the reference isodose and thus surgical damage is reduced. The amount of healthy tissues outside the target receiving considerable radiation is significantly reduced due to the decrease in irradiated volume. Dose homogeneity inside the implant is significantly improved. Although there is a slight increase of overdose volume inside the implant, this increase is considered to be negligible in clinical applications. PMID- 9364635 TI - Monte Carlo calculated dose distribution for endovascular HDR brachytherapy with Ir-192. AB - BACKGROUND AND PURPOSE: For endovascular HDR brachytherapy, very thin sources are required and the dose is specified at a short distance to the source centre down to 1.5 mm. The source which is used in the Nucletron HDR Selectron stepping source afterloader is treated by most dose calculation algorithms in clinical use as a point source, although its dimensions are large compared to these dose specification distances. Furthermore, inaccuracies might be introduced because consecutive dwell positions show an overlap of sources if the step size is smaller than the active length of the source. MATERIALS AND METHODS: In order to quantify these inaccuracies, we used the EGS4 Monte Carlo code to generate the dose distribution with 0.5 mm spatial resolution for a single source. From this, translation and superposition were used to calculate dose distributions for multiple dwell positions. The results are compared with those of other Monte Carlo computations and of a commercial brachytherapy planning system. RESULTS AND CONCLUSIONS: Our Monte Carlo calculations showed that secondary electrons have no relevant influence on the dose distribution and that errors up to 25% are made when using the point source approximation for irradiations with a single dwell position. However, when three or more dwell positions are used with equal dwell times, the total error becomes negligibly small because the errors from subsequent dwell positions compensate each other. At distances larger than 5 mm, there is a good match between the Monte Carlo data and those of point source algorithms for all clinical relevant cases. PMID- 9364636 TI - CT simulation in stereotactic brain radiotherapy--analysis of isocenter reproducibility with mask fixation. AB - BACKGROUND AND PURPOSE: CT verification and measurement of isocenter deviation using repeated mask fixation in linac-based stereotactic high dose radiotherapy of brain metastases were performed in this study. MATERIALS AND METHODS: For stereotactic radiotherapy of brain metastases a commercial head mask fixation device based on thermoplastic materials (BrainLAB) was used. A two-step planning treatment procedure was performed. Immediately before treatment the patient was relocated in the mask and a verification CT scan of the radiopaque marked isocenter was performed and if necessary its position was corrected. The verification procedure is described in detail. Twenty-two CT verifications in 16 patients were analyzed. Deviations were measured separately for each direction. A 3D-deviation vector was calculated. Additionally the average amount of deviation in each of the three dimensions was calculated. RESULTS: The mean deviation and standard deviation (SD) of the isocenter was 0.4 mm (SD 1.5 mm) in the longitudinal direction, -0.1 mm (SD 1.8 mm) in the lateral direction and 0.1 mm (SD 1.2 mm) in the anterior-posterior direction. The mean three-dimensional distance (3D-vector) between the verified and the corrected isocenter was 2.4 mm (SD 1.3 mm). The average deviation (without consideration of direction) was 1.1 mm (SD 1.1 mm), 1.3 mm (SD 1.3 mm) and 0.8 mm (SD 0.9 mm) in the longitudinal, lateral and sagittal directions, respectively. No correlation was found between 3D-deviation and the distance of the isocenter from the reference plane nor between deviation and the position of metastases in the brain (central versus peripheral or between different lobes), or the date of treatment. CONCLUSION: Reproducibility of the isocenter using the presented mask fixation is in the range of positioning reproducibility reported for other non-invasive fixation devices for stereotactic brain treatment. Our results underline the importance of CT verification as a quality assurance method in stereotactic radiotherapy. Under the condition of a preceding CT verification the mask can be used for single dose stereotactic radiotherapy. For fractionated stereotactic irradiation of small target volumes we recommend repeated CT verifications to assure reproducibility. PMID- 9364637 TI - A comparison of arc-based and static mini-multileaf collimator-based radiosurgery treatment plans. AB - BACKGROUND: The purpose of this study is to compare arc-based and mini-multileaf collimator (mMLC)-based radiosurgery treatment plans using isodose distributions and dose-volume histograms. METHODS: Of 11 patients who underwent conventional arc-based radiosurgery for intracranial malignancies, four were treated with one isocenter, four were treated with two isocenters and three were treated with three isocenters. The same cases were re-planned using a test version of mMLC based radiosurgery software for multiple static non-coplanar fields. RESULTS AND CONCLUSION: For non-spherical targets, treatment planning is relatively intuitive with mMLC-based radiosurgery, reducing the amount of time required for planning. Moreover, a lower dose of radiation is delivered to normal tissue with mMLC-based radiosurgery than with arc-based radiosurgery, which theoretically should lead to a reduced risk of complications. PMID- 9364638 TI - A new applicator design for endocavitary brachytherapy of cancer in the nasopharynx. AB - INTRODUCTION: In attempting to improve local tumor control by higher doses of radiation, there has been a resurgence of interest in the implementation of brachytherapy in the management of primary and recurrent cancers of the nasopharynx. Brachytherapy with its steep dose fall-off is of particular interest because of the proximity of critical dose limiting structures. Recent developments in brachytherapy, such as the introduction of pulsed-dose-rate and high-dose-rate computerized afterloaders, have encouraged further evolution of brachytherapy techniques. MATERIALS AND METHODS: We have designed an inexpensive, re-usable and flexible silicone applicator, tailored to the shape of the soft tissues of the nasopharynx, which can be used with either low-dose-rate brachytherapy or high (pulsed)-dose-rate remote controlled afterloaders. RESULTS AND CONCLUSIONS: This Rotterdam nasopharynx applicator proved to be easy to introduce, patient friendly and can remain in situ for the duration of the treatment (2-6 days). The design, technique of application and the first consecutive 5 years of clinical experience in using this applicator are presented. PMID- 9364639 TI - Fractionated stereotactic radiotherapy for choroidal melanoma. PMID- 9364640 TI - Histopathologic correlates of a positive bone scan. AB - The accumulation of radioactive tracer is associated with specific histological changes. Awareness of these changes permits a more specific interpretation of a positive bone scan, especially when correlating the radionuclide image with the plain radiographs. Increased uptake in the flow phase of an imaging study usually corresponds to differentiated vascular spaces. In the blood pool phase, tracer accumulation is caused by neovascularity, a feature of reactive granulation tissue or neoplastic angiogenesis. In the delayed phase, tracer uptake is attributable to osteoid production. With plain radiographic correlation, the manner of osteoid deposition--remodeling, endochondral, reactive, or neoplastic- can be determined. The knowledge of these histological features may help the nuclear radiologist make the correct diagnosis. PMID- 9364641 TI - Skeletal system: biomechanical concepts and relationships to normal and abnormal conditions. AB - The human skeleton is a remarkable organ that is uniquely designed to provide structural support and to house the body's hematopoietic system and mineral reservoirs. Seven concepts that will assist the clinician in understanding skeletal function are (1) material properties of bone, (2) stress and strain, (3) bending moments and torsional loads, (4) area moments of inertia, (5) fatigue and catastrophic failure, (6) Wolff's law, and (7) stress risers and open section effect. For example, as the modulus of a bone, a measure of stiffness decreases as in Padget's disease or fibrous dysplasia and the same levels of stress will cause greater deformations. The sum of these principles also explains the torus fracture (ductility), fracture of the olecranon by contracting tricep muscle (tensile loading), osteoporotic compression fracture of the spine, and the other biomechanical lesions that are encountered. Understanding these basic biomechanical principles can help physicians comprehend neoplastic processes and fractures that are the metabolic responses of the skeleton to stress and that appear on the radionuclide bone scan. PMID- 9364642 TI - Technical considerations for optimal orthopedic imaging. AB - Over the past 25 years bone scintigraphy has played an essential role in most Nuclear Medicine departments, accounting for 25% to 60% of the patient volumes. No longer is every bone scan ordered as part of a metastatic workup. Today radionuclide bone imaging (RNBI) is included in most orthopedic diagnostic pathways. It is necessary to optimize the bone scan procedure to be sensitive, to carefully localize abnormal uptake for diagnosis, to correlate the bone scans, plain radiographs, computed tomographic (CT) scans, and magnetic resonance (MR) scans that accompany the patient, and to be precise in reporting a final impression. This can be done through meticulous attention to the image acquisition so that it encompasses not only equipment specifications and acquisition parameters, but also patient history, preparation, imaging protocols, positioning, and image correlation. The importance of these considerations, the rationale to explain them, and suggested guidelines for their implementation will be discussed in this article. PMID- 9364643 TI - Radionuclide imaging in orthopedic infections. AB - In otherwise normal bone, Three Phase Bone Scintigraphy is sensitive and specific for osteomyelitis. In patients with underlying osseous abnormalities the specificity of the study is decreased. The four phase bone scan, bone/gallium scintigraphy, leukocyte imaging, leukocyte/bone and leukocyte/marrow studies have all been reported to increase specificity. The techniques, strategies, and limitations are discussed. No single study is equally useful in all situations. Labeled leukocyte imaging is of little value in vertebral osteomyelitis because this entity often presents as a nonspecific photopenic defect. The preferred technique for the spine is bone/gallium imaging. Intense uptake, on bone scintigraphy, in two adjacent vertebrae with loss of the disc space is highly suggestive of spinal osteomyelitis. Gallium not only enhances the specificity of the diagnosis but provides information about surrounding soft tissue infection. In the diabetic foot, labeled leukocyte imaging alone is sufficient to determine the presence of osteomyelitis in the fore--foot. In the midfoot and hindfoot it may be necessary to combine leukocyte scintigraphy with bone scintigraphy to precisely localize the infection. Labeled leukocytes accumulate in the uninfected neuropathic joint and preliminary data suggest that leukocyte/marrow imaging may be useful to determine the significance of such uptake. For the painful joint replacement, if infection is the primary concern, leukocyte/marrow scintigraphy should be performed initially. If any postoperative complication, regardless of type, is the concern, it is reasonable to begin with bone scintigraphy because a normal study rules strongly against any complication. An abnormal bone scan will require additional studies to more precisely determine the cause of that abnormality. PMID- 9364644 TI - Hip and knee prostheses: evaluation of the natural history of periprosthetic bone changes. AB - This is a review of normal adaptive bone remodeling in response to hip and knee endoprostheses as manifested by changes in regional bone mineral density and radiophosphate uptake as a function of time. The normal evolution of change may vary with the design and composition of the implant. Appreciation of the normal temporal alterations enhances the ability to disclose prosthetic complications, but it is not without its limitations. The literature reports on the efficacy of radiophosphate to detect implant loosening are variable and differ between those that are cemented and not. PMID- 9364645 TI - The role of nuclear medicine in primary bone and soft tissue tumors. AB - Although there is a limited role initially for staging the disease of primary bone and soft tissue tumors and for differentiation of benign from malignant lesions, nuclear medicine studies are recommended before starting treatment. A total body bone scan that includes a three phase study for the involved region helps to outline the vascularity of the lesion and both soft tissue and bony involvement, as well as involvement of other bones. A thallium 201 chloride or technitium 99m methoxy isobutyl isonitrile (SestaMIBI) tumor imaging study is recommended for baseline study and for future reference to evaluate the response to preoperative chemotherapy. This is of special importance to determine whether the patient needs an amputation or a limb-salvaging procedure. A follow-up thallium or 99mTc sesta MIBI study is not recommended early after surgery. A waiting period of at least 2 months is essential to avoid false-positive uptake caused by postoperative changes although this could be differentiated by comparing the ratios of lesion uptake in both early and delayed thallium imaging and with the ratios from the blood pool phase of the bone scan. Persistent thallium uptake in delayed images accompanied by ratios that are higher than the blood pool ratios is highly indicative of early recurrence. In the future, F-18 FDG tumor imaging acquired either on dedicated positron-emission tomography (PET) systems or by using a dual head gamma camera for coincidence detection will replace thallium and 99mTc sesta MIBI in those centers that have access to this technology. This is especially important at sites where thallium and MIBI have limitations because of normal uptake in adjacent organs. PMID- 9364646 TI - Radiosynovectomy's clinical applications and cost effectiveness: a review. AB - It is apparent that from the work of the authors and many others, including the work of Rivard, Sledge, Zuckerman, among others, that radiosynovectomy has an important role to play in providing effective treatment of affected joints associated with rheumatoid arthritis and other forms of arthritis as well as the hemophiliac joint. The treatment offers relief from the effects of recurrent joint effusion with an approximately 60% to 66% favorable response and from recurrent hemarthrosis in the hemophiliac joint with an approximately 75% to 80% favorable response. The impact of providing radiosynovectomy as an alternative to surgical synovectomy is seen, where postoperative side effects such as joint stiffness are avoided, improved quality of life is repeatedly documented, and the cost savings in health care dollars, particularly evident in the hemophiliac joint in this relatively small population, are potentially enormous. With almost two million people in the United States suffering from rheumatoid arthritis, the potential savings in health care dollars is also enormous. As with any use of in vivo radiopharmaceuticals, the potential for radiation-induced damage exists. However, with a 25 plus year record of use, more optimally configured radiopharmaceuticals, and the addition of maneuvers to minimize potential joint leakage, the risk of radiation induced damage appears to be minimal. It appears as though radiosynovectomy is an effective as well as cost-effective alternative to surgical synovectomy and is becoming the procedure of choice particularly in the hemophiliac patient with recurrent hemarthrosis and synovitis who has failed medical therapy. It is also the procedure of choice in patients for whom surgery is contraindicated because of the presence of clotting factor inhibitors. PMID- 9364647 TI - A musculoskeletal radiologist's view of nuclear medicine. AB - The introduction of cross-sectional and multiplanar imaging techniques has not diminished the value of radionuclide bone scanning. Skeletal scintigraphy remains an extremely effective and relatively inexpensive tool for diagnosis of many disorders of bones and joints. The sensitivity of scintigraphy in detecting stress fractures approaches 100%, although it is less specific than plain film radiography. However, radionuclide bone scanning can reveal subtle early changes in bone metabolism. For evaluation of infections, particularly in patients with diabetic foot neuropathy, scintigraphy is the modality of choice, although a combination of imaging techniques may be necessary in previously damaged bone. Radionuclide bone scanning has retained its place in the evaluation of primary bone tumors and metastases, and in screening of patients with metabolic bone disease. The radiologist should be aware that although this modality is generally used as an ancillary technique in conjunction with plain radiography, conventional tomography, computed tomography (CT), and magnetic resonance imaging (MRI), at times it can be used as the primary modality not only for the identification of skeletal lesions but also to provide important information required to make a definite diagnosis. PMID- 9364648 TI - The role of bone imaging in orthopedic practice. AB - Bone scans fill the void left by anatomical imaging by providing a metabolic assessment of change in local bone turnover associated with many common disorders of the skeleton. Bone scanning is valuable in uncovering skeletal lesions that are obscure, the extent of known lesions, and following their natural evolution. Its high sensitivity and relative ease makes it an extremely useful tool in the diagnosis and management of a wide variety of skeletal disorders. PMID- 9364649 TI - A semi-parametric estimate of extra-Poisson variation for vital rates. AB - We introduce a method for estimating overdispersion in Poisson models for vital rates. We assume smoothness conditions on the counts to obtain pointwise variance estimates that we combine to obtain an estimate of the overdispersion parameter. We create confidence intervals about the observed rates using this estimate and an approximation based on the gamma distribution. The advantage of this method is that the estimates of the superpopulation rates do not depend on the smoothness assumption, yet when this assumption is met we obtain approximately unbiased estimates of the overdispersion parameter. Thus, we may calculate confidence intervals for vital rates under an overdispersed Poisson model without making parametric assumptions on the mean rates. PMID- 9364650 TI - Analysis of ectopic pregnancy data using marginal and conditional models. AB - This work is motivated by a longitudinal study of women and their ectopic pregnancy outcomes in Lund, Sweden. In this article, we review and apply the Liang-Zeger methodology to the Lund ectopic pregnancy data set. We further analyse the ectopic pregnancy data using conditional modelling approaches suggested by Rosner and Bonney. From the Lund ectopic pregnancy data, we learned that PID is the strongest predictor of subsequent development of ectopic pregnancy and that there is a monotone relationship between PID severity and ectopic pregnancy. We also learned that the presence of mycoplasma from lower or upper genital tract sites at index laparoscopy is also a strong predictor of ectopic pregnancy. Other correlates of ectopic pregnancy include age at pregnancy and history of gynaecologic surgery. PMID- 9364651 TI - Logistic regression models with missing covariate values for complex survey data. AB - Maximum likelihood methods are used to incorporate partially observed covariate values in fitting logistic regression models. We extend these methods to data collected through complex surveys using the pseudo-likelihood approach. One can obtain parameter estimates of the logistic regression model using standard statistical software and their standard errors by Taylor series expansion or the jackknife method. We apply the approach to data from a two-phase survey screening for dementia in a community sample of African Americans age 65 and older living in Indianapolis. The binary response variable is dementia and the covariate with missing values is a daily functioning score collected from interviews with a relative of the study subject. PMID- 9364652 TI - Local estimation of smooth curves for longitudinal data. AB - Longitudinal data are commonly analysed using mixed-effects models in which the population growth curve and individual subjects' growth curves are assumed to be known functions of time. Frequently, polynomial functions are assumed. In practice, however, polynomials may not fit the data and a mechanistic model that could suggest a non-linear function might not be known. Recent, more flexible approaches to these data approximate the underlying population mean curve or the individual subjects' curves using smoothing splines or kernel-based functions. I apply the local likelihood estimation method of Tibshirani and Hastie and estimate smooth population and individual growth curves by assuming that they are approximately linear or quadratic functions of time within overlapping neighbourhoods. This method requires neither complete data, nor that measurements are made at the same time points for each individual. For descriptive purposes, this approach is easy to implement with standard software. Inference for the resulting curve is facilitated by the theory of estimating equations. I illustrate the methods with data sets containing longitudinal measurements of serum neopterin in an AIDS clinical trial, measurements of ultrafiltration rates of high flux membrane dialysers for haemodialysis, and measurements of the volume of air expelled by individuals. PMID- 9364653 TI - A revised assessment of the HIV/AIDS incubation period, assuming a very short early period of high infectivity and using only San Francisco public health data on prevalence and incidence. AB - A revised assessment of the HIV/AIDS incubation period has been made, based on an updated operational model that includes a very short early period of high infectivity, following recent work by Jacquez et al. and using AIDS incidence data from the San Francisco Department of Public Health, plus data on AIDS incidence and HIV prevalence in a specially recruited cohort from the San Francisco City Clinic. The incubation period has, approximately, a suitably scaled gamma distribution with 14 degrees of freedom and mean 12.8 (SE 0.2) years. This information is essential in interpreting data from other areas and regions where AIDS incidence figures only are available, and is in particular intended for applications to several countries in Europe. PMID- 9364654 TI - Pre-AIDS mortality in the Edinburgh City Hospital HIV cohort. AB - In this paper, we look at the incidence and predictive factors of pre-AIDS mortality among HIV-infected individuals, and injecting drug users (IDUs) in particular, and compare IDUs with non-IDUs. 627 patients (73 per cent IDUs) of the Edinburgh City Hospital HIV Cohort were enrolled pre-AIDS and followed up until September 1994. Analyses were performed using cumulative hazard and cumulative incidence estimators for a competing risks model, the Cox proportional hazards model and the non-parametric hazard estimator of Fusaro et al. (1993). The effects of age and CD4 T-lymphocyte cell count, progressively depleted during HIV progression, were investigated. 60 deaths occurred in AIDS-free patients during follow-up; 25 were drug-related deaths in IDUs. Pre-AIDS mortality was higher among IDUs than non-IDUs (p = 0.07). The cumulative incidences of pre-AIDS death after five years from enrollment were 11 per cent in IDUs and 6 per cent in non-IDUs; the cumulative AIDS incidences were, respectively, 19 per cent and 32 per cent. After eight years, cumulative pre-AIDS death incidence was 15 per cent among IDUs; cumulative AIDS incidence among IDUs was 35 per cent. Both groups had similar risks of medically-related (non-AIDS)-MRNA-death. Age and CD4 count were both individually predictive of MRNA death (relative risks (RRs); 2.1 per decade of life, p < 0.01; and 1.9 for each 100 cells per 100 microliters lost, p < 0.0001), although when used together age was less significant (RR 1.6, p = 0.07). Neither was statistically significant for drug-related mortality, although hazard may be lower in older individuals and may increase with falling CD4 count. The drug-related mortality was 1.1 per cent: 2.3 per cent in the first two years after enrollment, and 0.4 per cent thereafter. We conclude that older HIV infected individuals are at greater risk of medically-related death before AIDS. This risk increases as CD4 count declines. Drug-related hazard may be greater in younger individuals and may increase as CD4 counts fall, but neither effect was formally significant. PMID- 9364655 TI - Construction of hearing percentiles in women with non-constant variance from the linear mixed-effects model. AB - Current age-specific reference standards for adult hearing thresholds are primarily cross-sectional in nature and vary in the degree of screening of the reference sample for noise-induced hearing loss and other hearing problems. We develop methods to construct age-specific percentiles for longitudinal data that have been modelled using the linear mixed-effects model. We apply these methods to construct percentiles of hearing level using data from a carefully screened sample of women from the Baltimore Longitudinal Study of Aging. However, the variation in the residuals and random effects from the linear mixed-effects model does not remain constant with age and frequency of the stimulus tone. In addition, the distribution of the hearing levels is not symmetric about the mean. We develop a number of methods to use the output from the linear mixed-effects model to construct percentiles that do not have constant variance. We use a transformation of the hearing levels to provide for skewness in the final percentile curves. The change in the variation of the residuals and random effects is modelled as a function of beginning age and frequency and we use this variance function to construct the hearing percentiles. We present a number of approaches. First, we use the absolute values of the population residuals to model the total deviation about the mean as a function of beginning age and frequency. Second, we model the standard deviation in the person-specific (cluster) residuals as well as the standard deviation in the estimated random effects. Finally, we use weighted least squares with the regressions on the absolute cluster residuals and absolute estimated random effects where the weights are the reciprocal of the standard deviations of their estimates. PMID- 9364656 TI - Multiple testing to establish superiority/equivalence of a new treatment compared with kappa standard treatments. AB - In this paper we develop multiple hypotheses testing procedures to compare a new treatment with a set of standard treatments in a clinical trial. The aim is to classify the new treatment with respect to each of the standards, by specifying those to which the new treatment is superior, those to which the new treatment is equivalent and those to which one can establish neither superiority nor equivalence. We propose several stepwise procedures and compare them with respect to their familywise error rates and power. The step-down methods SD1 and SD2 test for superiority first, followed by tests for equivalence for those comparisons where we cannot establish superiority. The step-up methods SU1 and SU2 test for equivalence first, followed by tests for superiority for those comparisons where we can establish at least equivalence. The methods SD3 and SU3 apply the tests for superiority and equivalence in pairs. All the methods require that we specify a threshold value delta > 0 in advance for defining equivalence. In applications where it is not possible to specify a value delta, we can use the method SD1 by testing for superiority first, followed by one-sided confidence limits on the efficacy differences for those comparisons where we cannot establish superiority. PMID- 9364657 TI - The molecular genetics of pancreatic cancer. AB - Pancreatic cancer is the fifth leading cause of cancer death in the United States, and despite improvements in the results of surgical treatment for this disease, little impact has been made upon overall mortality. New advances in treatment will depend upon improved adjuvant therapy, early diagnosis, and a better understanding of tumor biology. This article summarizes the results of molecular genetic studies in pancreatic cancer and their potential clinical significance. Familial predisposition to pancreatic cancer, cytogenic studies, DNA ploidy analysis, and examination of specific oncogenes and tumor suppressor genes are reviewed. The most frequent mutations detected have been in the K-ras oncogene, which occur in 80% of pancreatic cancers. These mutations do not correlate with tumor stage or survival, but can be useful in differentiating pancreatic exocrine from endocrine tumors and chronic pancreatitis. Mutations in the p53 gene occur in approximately 50% of tumors, and appear to be an independent prognostic factor for patient survival. Mutations in the CDKN2 gene are frequently seen in sporadic pancreatic cancers, and have been implicated in cases of familial pancreatic cancer. The significance of mutations in APC, MCC, DCC, c-erbB-2, RB-1, and mismatch repair genes in the genesis of pancreatic cancer is less clear. PMID- 9364658 TI - Management strategies for colorectal liver metastases--Part I. AB - Colorectal cancer is a common malignancy and the incidence of this disease is increasing. Approximately 50% of patients with colorectal cancer die from recurrent disease following an apparently curative resection of the primary tumour and the liver is the most frequent site of relapse. Although only a small proportion of patients will benefit from resection of liver metastases, this form of treatment offers the only possibility of cure. In selected patients, 5-year survival rates of 25-35% may be achieved following liver resection. A poor prognosis after resection of hepatic metastases is likely when there are more than three metastatic deposits, involved resection margins often as a result of ?wedge' resections, when there is extrahepatic disease, or when there is nodal involvement at the primary tumour site. Regional hepatic artery infusion chemotherapy may provide palliation and possibly even prolongation of survival for some patients with unresectable metastases. Cytoreductive techniques may also provide palliation in selected patients with hepatic metastases unsuitable for resection; cryotherapy is the most promising of these methods. PMID- 9364659 TI - Management strategies for colorectal liver metastases--Part II. AB - Liver metastases are relatively common in colorectal cancer and a small proportion of patients may benefit from resection of these liver metastases. In a selected subgroup of patients, 5-year survival rates of 25-35% may be achieved following liver resection. These survival figures compare favourably with those of patients with untreated liver secondaries. In the second part of this review the surgical and non-surgical treatment options for treating colorectal liver metastases are examined in detail. PMID- 9364660 TI - Insulinoma: a review of current management. AB - Insulinomas are a relatively rare tumour which occur predominantly in the pancreas. The majority of the tumours are benign, but have profound effects upon the patient. The diagnosis of insulinoma is often elusive, and the management may involve demanding surgery with a significant morbidity. In this review article, all clinical aspects of insulinomas are examined. Particular emphasis is placed on the myriad modes of presentation, and the methods used to localise the tumour pre-operatively. Medical, as well as surgical treatments are discussed and their role in the management of both malignant and benign tumours. Despite potential difficulties encountered in managing patients with this tumour, a large majority may be either cured or achieve useful palliation. PMID- 9364661 TI - Background genes: out of sight, but not out of brain.... PMID- 9364663 TI - Do we need a limbic system? PMID- 9364662 TI - Relevance of 'adaptive' mutations arising in non-dividing cells of microorganisms to age-related changes in mutant phenotypes of neurons. AB - Brattleboro rats do not produce vasopressin (VP) because of a germ-line single base deletion (di) that causes a frame shift downstream from the VP sequences and a loss of a stop codon. The resulting frame-shifted peptide precursor does not enter the secretory pathway in hypothalamic neurons, thereby blocking the neurosecretion of VP and other peptides. Yet, from birth onwards, a subpopulation of neurons in di/di rats slowly accumulates revertant cells with a hemizygous wild-type phenotype. Because the rate of reversion during aging is slowed by vasopressin infusion, it is of interest to consider these phenomena in relation to recent observations on 'adaptive' mutations in single cell bacteria and yeast that enable reversion of mutations that blocked cell division under conditions of nutrient deficits. In considering mechanisms that could produce revertant phenotypes in non-dividing cells of both pro- and eukaryotes, we note the pertinence of transcription-coupled repair and SOS 'error-prone' repair. PMID- 9364664 TI - Do we need a limbic system? PMID- 9364665 TI - Neurulation: coming to closure. AB - Neurulation is a morphogenetic event par excellence. During this highly choreographed four-dimensional process, a flat sheet of ectoderm is transformed into an elongated tubular rudiment, the neural tube, which exhibits rostro-caudal and mediolateral regionalization. Many tissues interact during neurulation to induce and regionalize the neuroectoderm and to produce the morphogenetic forces that drive neurulation. Such forces are generated by fundamental cell behaviors such as changes in cell shape, position and number. In addition, morphoregulatory molecules expressed during neurulation underlie induction and patterning of the forming neuraxis. Despite recent advances in our understanding of neurulation, neural tube defects continue to be a major health care concern. Further research, utilizing a panoply of approaches, is necessary to resolve this issue. Thus, although we are beginning to come to closure in terms of understanding the cellular and molecular mechanisms responsible for normal neural tube formation, 'coming to closure' is exactly the problem that requires resolution to prevent these devastating birth defects. PMID- 9364666 TI - Organization of intra-amygdaloid circuitries in the rat: an emerging framework for understanding functions of the amygdala. AB - The amygdala is located in the medial aspects of the temporal lobe. In spite of the fact that the amygdala has been implicated in a variety of functions, ranging from attention to memory to emotion, it has not attracted neuroscientists to the same extent as its laminated neighbours, in particular the hippocampus and surrounding cortex. However, recently, principles of information processing within the amygdala, particularly in the rat, have begun to emerge from anatomical, physiological and behavioral studies. These findings suggest that after the stimulus enters the amygdala, the highly organized intra-amygdaloid circuitries provide a pathway by which the representation of a stimulus becomes distributed in parallel to various amygdaloid nuclei. As a consequence, the stimulus representation may become modulated by different functional systems, such as those mediating memories from past experience or knowledge about ongoing homeostatic states. The amygdaloid output nuclei, especially the central nucleus, receive convergent information from several other amygdaloid regions and generate behavioral responses that presumably reflect the sum of neuronal activity produced by different amygdaloid nuclei. PMID- 9364667 TI - GABAA, NMDA and AMPA receptors: a developmentally regulated 'menage a trois'. AB - The main ionotropic receptors (GABAA, NMDA and AMPA) display a sequential participation in neuronal excitation in the neonatal hippocampus. GABA, the principal inhibitory transmitter in the adult CNS, acts as an excitatory transmitter in early postnatal stage. Glutamatergic synaptic transmission is first purely NMDA-receptor based and lacks functional AMPA receptors. Therefore, initially glutamatergic synapses are 'silent' at resting membrane potential, NMDA channels being blocked by Mg2+. However, when GABA and glutamatergic synapses are coactivated during the physiological patterns of activity, GABAA receptors can facilitate the activation of NMDA receptors, playing the role conferred to AMPA receptors later on in development. Determining the mechanisms underlying the development of this 'menage a trois' will shed light not only on the wide range of trophic roles of glutamate and GABA in the developing brain, but also on the significance of the transition from neonatal to adult forms of plasticity. PMID- 9364668 TI - Immortalized neural progenitor cells for CNS gene transfer and repair. AB - Immortalized multipotent neural stem and progenitor cells have emerged as a highly convenient source of tissue for genetic manipulation and ex vivo gene transfer to the CNS. Recent studies show that these cells, which can be maintained and genetically transduced as cell lines in culture, can survive, integrate and differentiate into both neurons and glia after transplantation to the intact or damaged brain. Progenitors engineered to secrete trophic factors, or to produce neurotransmitter-related or metabolic enzymes can be made to repopulate diseased or injured brain areas, thus providing a new potential therapeutic tool for the blockade of neurodegenerative processes and reversal of behavioural deficits in animal models of neurodegenerative diseases. With further technical improvements, the use of immortalized neural progenitors may bring us closer to the challenging goal of targeted and effective CNS repair. PMID- 9364669 TI - Analyzing the functional consequences of transmitter complexity. AB - Neurons and other cells are regulated by a great multiplicity of neurotransmitters, modulators, hormones and other chemical messengers, which, through complex networks of extensively diverging and converging pathways, exert a multiplicity of effects. How do we analyze the functioning of such a complex network? If the effects of a transmitter depend on the presence of many other transmitters, how can we predict what they will be? If multiple transmitters act through the same network, how can their actions be specific? If they converge on the same effects, are some of the transmitters redundant? Why are there so many transmitters? Such questions can be addressed using an analytical approach that examines, qualitatively or quantitatively, how the operation of the network globally maps a multidimensional input space of transmitters to a multidimensional output space of effects. PMID- 9364671 TI - Immunization of pregnant women could protect babies from vaccine associated poliomyelitis. PMID- 9364670 TI - OPV vs IPV--could placental immunity reduce the number of vaccine-associated paralytic poliomyelitis? PMID- 9364672 TI - The adjuvant MF59 increases the immunogenicity and protective efficacy of subunit influenza vaccine in mice. AB - The immunogenicity and protective efficacy of influenza vaccine with and without the adjuvant MF59 was determined in mice. The addition of MF59 significantly increased the antibody response to the vaccine antigens over a wide dose range. Equivalent antibody titres were seen using 50- to 200-fold lower antigen concentrations when combined with MF59 compared with vaccine alone. The humoral response was sustained for at least 6 months after immunization. The addition of MF59 increased the protective efficacy of the vaccine: the amount of live virus detectable in the lungs of mice challenged with virus 1-6 months after immunization was reduced and the rate of survival was significantly increased. Influenza vaccine combined with MF59 gave full protection from viral challenge at antigen doses 65- to 80-fold lower than with vaccine alone. PMID- 9364673 TI - Chronic local tissue reactions, long-term immunogenicity and immunologic priming of mice and guinea pigs to tetanus toxoid encapsulated in biodegradable polymer microspheres composed of poly lactide-co-glycolide polymers. AB - Immunogenicity of tetanus toxoid (TT) encapsulated in biodegradable polymer microspheres composed of poly lactide (PLA) or poly lactide-co-glycolide (PLGA) polymers was evaluated in mice and guinea pigs for 1 year. Microsphere formulations made from polymers differing in molecular weight and composition elicited significantly higher IgG antibody levels than soluble TT in mice. The antibody levels elicited by microsphere formulations in mice and guinea pigs were similar to those elicited by a single injection of AlPO4 adsorbed TT. Immunogenicity was not consistently better with a particular polymer composition, molecular weight or microsphere size. However, animals primed with TT-containing microspheres showed significantly higher anamnestic response to a low dose booster 1 year after priming than those primed with AlPO4 adsorbed TT. Microspheres made from low molecular weight PLGA polymer showed a minimal local tissue reaction 1 year after injection. In contrast, aluminum adjuvant formed local granulomas which persisted for 1 year after injection. Microsphere formulations used in this study released a small fraction of antigenic TT during in vitro release studies due to denaturation of TT during encapsulation and hydration of microspheres. Nevertheless, strong priming of immune responses were seen. It remains to be demonstrated whether stabilization of TT would lead to more immunogenic microsphere formulations. PMID- 9364674 TI - Hepatitis B vaccine containing surface antigen and selected preS1 and preS2 sequences. 1. Safety and immunogenicity in young, healthy adults. AB - The safety and immunogenicity of a yeast-derived recombinant hepatitis B virus (HBV) vaccine containing surface antigen (S) and selected preS1 and preS2 sequences (S-L*) were compared with those of a vaccine prepared with S alone (Engerix-B). S-L* consisted of composite particles containing S and L* at a ratio of 70/30. L* encompassed amino acid residues 12-52 of preS1 residues 133-145 of preS2, and the entire S domain. A total of 100 healthy, HBV-seronegative, young adults were randomized to receive 20 micrograms/dose of either S-L* or Engerix-B under double-blind conditions according to a 0-, 1-, 2-, 12-month schedule. In vivo humoral and in vitro lymphoproliferative responses to S and preS regions were monitored. Addition of the selected preS sequences to S did not enhance the in vivo humoral anti-HBs response but improved the in vitro stimulating capacity of the antigen (L*) in S-L* primed subjects. PMID- 9364675 TI - Hepatitis B vaccine containing surface antigen and selected preS1 and preS2 sequences. 2. Immunogenicity in poor responders to hepatitis B vaccines. AB - The immunogenicity of a yeast-derived recombinant hepatitis B virus (HBV) vaccine containing surface antigen (S) and selected preS1 and preS2 sequences (S-L*) was compared with that of a vaccine containing S alone (Engerix-B) in 32 healthy adults with a previous history of poor response (anti-HBs < 10 mIU ml-1) after at least three consecutive monthly doses of hepatitis B vaccines. The poor responders were randomized to receive three additional 20-microgram doses of either S-L* or Engerix-B in a double-blind fashion according to a 0-, 1-, 2-month schedule. In vivo humoral and in vitro lymphoproliferative responses to the S and preS regions were monitored. Although the addition of the selected preS sequences to S did not enhance the in vivo humoral anti-HBs response, the administration of the three additional vaccine doses, irrespective of their preS content, induced seroprotective anti-HBs levels in most vaccinees (29/32, 91%). In vitro proliferative responses to HBV surface antigens were only observed in subjects displaying anti-HBs titers > 1000 mIU ml-1 after the third additional vaccine dose. PMID- 9364676 TI - The immune response to a B-cell epitope delivered by Salmonella is enhanced by prior immunological experience. AB - Attenuated, heterologous strains of Salmonella have shown potential as live, recombinant vaccines against foreign pathogens. Studies in animal models have demonstrated that immunization with these heterologous vaccines is an effective way to induce both cellular and humoral immune responses against Salmonella and the foreign antigen. We studied the consequence of priming mice with Salmonella dublin 3-6 months before intraperitoneal administration with the same strain carrying a model B-cell epitope. Mice primed with the carrier strain demonstrated enhanced serum Ig titres against the foreign antigen. This immune enhancement was observed up to approximately 6 months after priming. These findings suggest that previous immunological experience with Salmonella does not limit the immune response to a foreign antigen carried by the same organism. In fact, prior exposure to Salmonella appears to enhance the response to the foreign antigen. PMID- 9364677 TI - Induction of neutralizing antibody in mice by immunization with recombinant 56 kDa protein of Orientia tsutsugamushi. AB - Anti-oriential antibody inhibits Orientia tsutsugamushi attachment to, and penetration of, host cells. However, O. tsutsugamushi antigens that induce the production of a neutralizing antibody have not been identified. The authors immunized mice and rabbits with the recombinant 56 kDa protein of O. tsutsugamushi fused to the maltose binding protein of Escherichia coli (MBP Bor56) and analysed their effect on O. tsutsugamushi attachment to or penetration of L929 cells. O. tsutsugamushi attachment and penetration were measured by using an indirect immunofluorescent antibody assay (IFA). O. tsutsugamushi growth in L929 cells was determined by [3H]thymidine uptake assay. By IFA, we observed a 96% reduction of attachment or penetration of O. tsutsugamushi treated with rabbit anti-MBP-Bor56 sera. [3H]thymidine uptake showed that mouse anti-MBP-Bor56 sera caused a 91% reduction in O. tsutsugamushi growth, when compared to mouse anti-MBP sera. These results suggest that the 56 kDa protein of O. tsutsugamushi plays an important role in O. tsutsugamushi attachment to or penetration of cells. PMID- 9364678 TI - The muramyl dipeptide analog GMTP-N-DPG preferentially induces cellular immunity to soluble antigens. AB - GMTP-N-DPG (N-acetylglucosaminyl-N-acetylmuramyl-L-alanyl-D-isoglutamyl- L-alanyl dipalmitoylpropylamide) is a lipophilic derivative of the immunologically active compound MDP and has adjuvant properties. GMTP-N-DPG was compared with other adjuvants in model vaccine systems using ovalbumin (OVA) and a synthetic peptide derived from pp89 of murine cytomegalovirus as antigens. When serum from C57/Bl mice immunized with OVA was tested for the presence of anti-OVA antibody, samples from mice immunized with OVA plus GMTP-N-DPG had ELISA optical density (O.D.) readings twice as high as those from mice immunized with antigen alone. In contrast, samples from mice immunized with the liposomal monophosphoryl lipid A (MPL) formulation exhibited ELISA O.D. readings tenfold higher than samples from mice immunized with antigen alone. Relative levels of specific antibody in serum samples from mice immunized with OVA plus the saponin adjuvant QS-21 were equal to the GMTP-N-DPG samples. When spleen cells from immunized mice were tested for their proliferative response to OVA, we found that liposomal MPL was again the optimal adjuvant, whereas the proliferative responses of cells from mice immunized with GMTP-N-DPG or QS-21 were no better than cells from mice immunized with OVA alone. In contrast to the relatively low antibody and proliferation levels, spleen cells from mice immunized with GMTP-N-DPG and OVA demonstrated the highest level of anti-OVA CTL activity. Spleen cells from mice immunized with the pp89 peptide plus GMTP-N-DPG also exhibited CTL activity. Using antibody and complement mediated cytotoxicity it was determined that the CTL were CD8+. Based on these results, we believe that GMTP-N-DPG may be an excellent candidate adjuvant in vaccines for diseases in which a strong cell-mediated response is desired. PMID- 9364679 TI - Effect of IL-4 and IL-12 liposomal formulations on the induction of immune response to bovine herpesvirus type-1 glycoprotein D. AB - Activation of different T-helper (Th) responses following immunisation has profound and specific influences on the development of the immune response and on the ability of a vaccine to confer protection. Since cytokines are capable of influencing the stimulation of distinct T-cell responses, their encapsulation in vaccines should modulate antigen-specific immune responses. Unfortunately, the use of cytokines in vivo is hampered by their rapid clearance and inactivation. One possible solution to this problem is the use of liposomes to entrap both cytokines and antigen. This approach will not only protect the cytokine but will also deliver the two components simultaneously to the same site. The authors examined, therefore, the immune responses elicited by systemic immunisation of mice with liposome formulations containing a truncated form of bovine herpesvirus type-1 glycoprotein D (tgD) together with IL-4 or IL-12. Subcutaneous immunisation with liposomes containing tgD and IL-12 significantly enhanced the induction of antigen-specific cellular and humoral immune responses. These responses were characterised by an increase in IFN-gamma secreting cells and the induction of tgD-specific IgG2a antibodies. In contrast, encapsulation of IL-4 into tgD-liposomes did not enhance the humoral immune response to gD but significantly influenced the development of antigen-specific IL-4 secreting cells. Our results indicated that encapsulation of IL-12 into the liposomes was necessary for the systemic adjuvant effect and demonstrated the feasibility of using liposome technology and cytokines to manipulate the development of different antigen-specific Th subsets in vivo. PMID- 9364680 TI - Colinear synthesis of an antigen-specific B-cell epitope with a 'promiscuous' tetanus toxin T-cell epitope: a synthetic peptide immunocontraceptive. AB - Carrier conjugation is commonly used to provide T-cell help for small, linear peptides containing antigen-specific B-cell epitopes. However, carrier conjugation is expensive, variable and often results in adverse side effects if the conjugate is administered repeatedly. To eliminate the need for carrier conjugation, we examined two synthetic peptides for their ability to elicit sustained antibody titres in female rabbits and baboons. One peptide (hC1-20) was based on the sequence of the sperm-specific isozyme of human lactate dehydrogenase (LDH-C4). This peptide stimulates helper T-cell responses. The other peptide (bC5-19:TT) was a chimera between an LDH-C4 B-cell epitope and a 'promiscuous' T-cell epitope from tetanus toxin which has been shown to bind to and stimulate many different major histocompatibility complex alleles. Both peptides were immunogenic in rabbits and baboons. The chimera elicited consistently high antibody titres and was immunogenic in 19/19 wild-caught female baboons. When 14 bC5-19:TT immunized baboons were mated, their fertility was reduced by 62% compared with controls (P < 0.02). This carrier-free construct can be incorporated into biodegradable microspheres which may provide long-term protection from pregnancy with a single dose. PMID- 9364681 TI - Effect of microencapsulation on immunogenicity of a bovine herpes virus glycoprotein and inactivated influenza virus in mice. AB - We previously found that aqueous-based spermine-alginate or spermine-chondroitin sulfate microcapsules enhanced rotavirus-specific humoral immune responses after intramuscular inoculation of mice. To extend our observations with whole, infectious rotavirus to vaccine strategies which include inactivated virus and purified proteins, we determined the capacity of aqueous-based microcapsules to enhance virus-specific immune responses to bovine herpes virus type 1 glycoprotein D (BHV-1-gD) or ether-treated influenza virus. We found that spermine-alginate microcapsules decreased the quantity of BHV-1-gD necessary to induce protein-specific antibodies about 5000-fold. However, spermine-alginate microcapsules did not enhance influenza virus-specific antibody responses. Microcapsules composed of spermine-chondroitin sulfate did not enhance either BHV 1-gD or influenza virus-specific immune responses. Possible mechanisms of enhancement of virus-specific antibody responses by microencapsulation are discussed. PMID- 9364682 TI - CTL induction using synthetic peptides delivered in emulsions--critical role of the formulation procedure. AB - Emulsions have been used with variable degrees of success to deliver antigen to stimulate immune responses. We have investigated three different ways of incorporating peptide antigen into soybean emulsions to induce CTL responses in mice. Two of these emulsions (oil-in-water, o/w, and water-in-oil-in-water, w/o/w) had peptide incorporated at the formulation stage, while the third had peptide added to a pre-formed o/w emulsion. High levels of CTL activity were induced when peptide was dispersed into the o/w or w/o/w emulsions, in contrast to addition of peptide to the pre-formed o/w emulsion, which did not stimulate a CTL response. Induction of CTL activity was independent of emulsion globule size but was correlated with a negative zeta potential and dispersion of peptide in the oil phase. The ability of peptide in soybean oil emulsion to induce CTL is critically dependent on dispersion of peptide at the time of emulsion formation. PMID- 9364683 TI - Comparative efficacy of a Coxiella burnetii chloroform:methanol residue (CMR) vaccine and a licensed cellular vaccine (Q-Vax) in rodents challenged by aerosol. AB - Q fever is an acute and self-limited febrile illness caused by the obligate intracellular bacterium Coxiella burnetii. While phase I cellular Q fever vaccines are efficacious in humans, vaccination of immune individuals may result in sterile abscesses and granulomas. The chloroform:methanol residue vaccine (CMR) was developed as a safer alternative. The efficacy of a licensed phase I cellular vaccine (Q-Vax) was compared with that of CMR vaccine in A/J mice and Hartley guinea pigs challenged with virulent phase I C. burnetii by aerosol. Both vaccines were efficacious. The CMR vaccine dose required to protect 50% of mice (PD50) against lethal aerosol challenge (11 LD50) was one-third of the Q-Vax dose. However, the PD50 for CMR was four times the Q-Vax dose in guinea pigs challenged by aerosol (60 LD50). It was concluded that CMR is an efficacious alternative to cellular Q fever vaccines for the prevention of Q fever. PMID- 9364684 TI - Effects of frequent intranasal administration of adjuvant-combined influenza vaccine on the protection against virus infection. AB - In previous papers, we have shown that Escherichia coli heat-labile enterotoxin B subunit, supplemented with a trace amount of the holotoxin (LTB*) could be used as a potent adjuvant for a nasal influenza HA (haemagglutinin) vaccine in humans. The present study was designed to determine whether the effectiveness of a combined LTB*-HA vaccine could be limited by preexisting immunity to LTB and how many times the adjuvant-combined vaccine could be administered intranasally without reducing its protective efficacy in BALB/c, C3H and B10 mice. The magnitude of both nasal and serum Ab responses to HA vaccine was correlated with the degree of protection against virus infection. Higher doses of LTB*-combined vaccine were required for inducing high enough levels of anti-HA Ab responses to provide complete protection in low responder mice. Repeated pretreatments with LTB* alone (more than six times), which provided high levels of preexisting Abs to LTB, inhibited the induction of anti-HA Ab responses and reduced the protective efficacy of the adjuvant-combined vaccine. However, the LTB*-combined vaccine could be given repeatedly (about ten times) to mice without reducing the effectiveness of the adjuvant-combined vaccine. These results suggest that the LTB*-combined nasal influenza vaccine can be given to humans once every few years when an epidemic of influenza may occur. PMID- 9364685 TI - Twenty-three-year follow-up study of rubella antibodies after immunization in a closed population, and serological response to revaccination. AB - Twenty-six institutionalized children immunized with a Japanese rubella vaccine, Matsuba strain, have been observed for 23 years and the persistence of vaccine induced rubella immunity documented. All vaccinees were shown to have seroconverted to rubella virus in a haemagglutination inhibition (HI) test, and the geometric mean titre (GMT) of rubella HI antibody rose to 2 5-8 months after vaccination (Ueda et al., Acta Paediatrica Japonica, Overseas Edition 1978, 20, 8 14). The GMT then declined gradually to 2 23 years after inoculation, except in four cases (15.4%) which had reverted to negative. However, three of the four maintained a rubella HI antibody titre of 1:4. Twelve of the 26 vaccinees were revaccinated 24 years after primary vaccination, and all ten cases having initial titres of < or = 1:16 demonstrated secondary responses. Rubella immunity induced by vaccination had persisted, so routine booster immunization did not seem necessary. However, a second immunization programme should be considered to achieve high antibody-positive rates and to protect against primary vaccine failure. PMID- 9364686 TI - Induction of protective immunity to Theileria annulata using two major merozoite surface antigens presented by different delivery systems. AB - Allelic forms (Tams1-1 and Tams1-2) of the major merozoite surface antigen gene of Theileria annulata have recently been expressed in Escherichia coli and in Salmonella typhimurium aroA vaccine strain SL3261. To test the potential of subunit vaccines against T. annulata infection, we immunized four groups of three calves with either recombinant (re-) (Tams1-1 and Tams1-2) proteins or naked DNA encoding these antigens. Group I was immunized intramuscularly with both re proteins incorporated into immunostimulating complexes (ISCOMs). Group II was inoculated intramuscularly with naked plasmid DNA encoding Tams1-1 and Tams1-2. Groups III and IV received S. typhimurium SL3261 [pSTams1-1][pIP5] and SL3261 [pSTams1-2] [pIP5] subcutaneously and orally, respectively. A final group of three animals (Group V) served as an unimmunized control group. Four weeks after the last immunization all calves were challenged with a T. annulata stabilate generated from blood of an infected animal with 30% piroplasm parasitaemia. All calves vaccinated with ISCOMs proved to be protected from T. annulata infection and had generated antibodies against both re-(Tams1-1 and Tams1-2) at the time of challenge. In two of these animals the antibody had a surface binding profile by IFAT. Two of three calves immunized with naked DNA also proved to be protected, but none of the animals had generated any detectable antibodies against the recombinants. Salmonella-based delivery of the recombinants did not induce any protection; two of six animals died of theileriosis and there was no difference between subcutaneous or oral administration. These preliminary results show that re-(Tams1-1 and/or Tams1-2) may elicit protective immune responses in cattle, depending on the antigen delivery system. PMID- 9364687 TI - Human antibodies to the conserved region of the M protein: opsonization of heterologous strains of group A streptococci. AB - A 20-mer peptide (p145) in the carboxyl-terminal region of the M protein of group A streptococci (GAS) has previously been defined as the target of bactericidal antibodies. Sequence analysis of seven field isolates from indigenous Australians living in an area highly endemic for GAS and five laboratory reference strains (encompassing nine unique serotypes plus three nontypeables) demonstrates that this region is highly conserved (sequence identity ranging from 65 to 95%) with six of the 12 sequences being identical to p145. Most of the sequence dissimilarity is contained within the last seven amino acids of p145. Competitive ELISA demonstrates that human antibodies specific for p145 cannot discriminate between p145 and synthetic peptides representing four from four of the variant sequences tested. Ig purified from endemic sera was able to opsonize each of the GAS isolates and free p145 as well as a peptide expressing a minimal conformational epitope within p145 (requiring amino acids between positions 2 and 13 of p145), but not an irrelevant peptide, were able to partially or completely inhibit opsonization of all isolates and reference strains. Thus adult endemic sera contain antibodies which are bactericidal for multiple GAS serotypes and which are specific for a sequence of 12 amino acids contained within the p145 region of the M protein. PMID- 9364688 TI - Prevention and control of hepatitis B in central and eastern Europe and the newly independent states, Siofok, Hungary, 6-9 October 1996. PMID- 9364689 TI - Immunobiological activities of chemically defined lipid A from Helicobacter pylori LPS in comparison with Porphyromonas gingivalis lipid A and Escherichia coli-type synthetic lipid A (compound 506). AB - Helicobacter pylori lipid A, characterised by a glucosamine beta (1-6) disaccharide 1-(2-aminoethyl)phosphate acylated by (R)-3-hydroxyoctadecanoic acid and (R)-3-(octadecanoyloxy)octadecanoic acid at the 2- and 2'-positions, respectively, exhibited no or very low endotoxic activities, i.e. lethal toxicity in galactosamine-loaded mice, pyrogenicity for rabbits and the activity of the Limulus test compared with Escherichia coli-type synthetic lipid A (compound 506), which possesses beta-(1-6)-linked glucosamine disaccharide 1,4' bisphosphate, with two acyloxyacyl groups at the 2'- and 3'-positions and two 3 hydroxytetradecanoyl groups at the 2- and 3-positions. The endotoxic properties of H. pylori lipid A were also a little weaker than those of the low endotoxic lipid A of P. gingivalis, which has 1-phospho beta-(1-6)-linked glucosamine disaccharide with 3-hydroxy-15-methylhexadecanoyl and 3-hexadecanoyloxy-15 methylhexadecanoyl groups at the 2- and 2'-positions, respectively. Further, the mitogenic activity of H. pylori lipid A in murine splenic mononuclear cells was also less than those of P. gingivalis lipid A and compound 506. However, H. pylori lipid A induced comparable production of interleukin-6 (IL-6) by human peripheral blood mononuclear cells (PBMC) compared with P. gingivalis lipid A and compound 506. H. pylori lipid A also increased human natural killer cell activity, and strongly agglutinated rabbit erythrocytes. However, the lipid As of H. pylori and P. gingivalis showed lower activities in inducing tumour necrosis factor alpha (TNF-alpha) production by human PBMC and IL-8 production by human gingival fibroblasts than that of compound 506. The structural feature of H. pylori lipid A may be associated with low endotoxic properties and potent immunobiological activities. PMID- 9364690 TI - A randomized double-blind trial comparing a two-component acellular to a whole cell pertussis vaccine in Senegal. AB - A randomized, double-blind trial comparing a diphtheria-tetanus-acellular pertussis vaccine (DTaP) (pertussis toxoid and filamentous hemagglutinin) with a whole-cell vaccine (DTwP) was conducted. A case-contact study was nested in the trial to estimate absolute efficacy. From 1990 through 1994, 4181 children were randomized to receive one of the vaccines at 2, 4, and 6 months. Severe adverse events were monitored weekly during two visits after vaccination. Fewer serious adverse events were observed after DTaP. Surveillance for cough illnesses persisting more than 7 days, in children under 15 years of age, was made by weekly home visits. Examining physicians, blind to vaccination status, took samples for culture and serologic testing. Pertussis was defined as 21 or more days of cough confirmed by culture, serology, or contact with a culture-confirmed person. Beginning 28 days after the third vaccine dose, the overall ratio of pertussis incidence in the DTaP group relative to the DTwP group (RRac/wc) was 1.54 (95% CI, 1.23-1.93). In children younger than 18 months of age, RRac/wc was 1.16 (95% CI, 0.77-1.73) and 1.76 (95% CI, 1.33-2.33) in children older than 18 months, which suggests a shorter duration of protection with the acellular vaccine (P = 0.090). Absolute efficacy estimates derived from the case-contact study confirmed the lower protection afforded by the acellular vaccine compared with the whole-cell vaccine: 31% (95% CI, 7-49) versus 55% against the protocol case definition, and 85% (95% CI, 66-93) versus 96% for the more severe WHO case definition. Although vaccination with DTaP provided a lower degree of protection than the highly effective DTwP, this difference was less prominent before 18 months of age, the customary age for a fourth dose. The safer DTaP vaccine may prove a valuable substitute for whole-cell vaccines when used in a schedule that includes a booster-dose. PMID- 9364692 TI - An effective intradermal hepatitis B vaccination. AB - Small dose intradermal (i.d.) inoculation methods of hepatitis B vaccine have been reported to be effective and economical. We determined the best method to obtain high antibody levels within a short period of time and for the long-term maintenance of these levels. A total of 173 female students were randomly allocated to seven groups: six i.d. inoculation groups, to which 6-12 micrograms was administered in three or four divided doses (Groups A-F), and a control group (Group G) which received three 10 micrograms intramuscular (i.m.) inoculations. Serum hepatitis B antibody levels were quantified in weeks 4 and 8, and months 4, 7, and 12. Positivities in all groups were not significantly different at each measurement time. In month 4, geometric mean antibody levels in the three i.d. groups (10-12 micrograms in three divided doses; 79.1-107.0 IU l-1) were significantly higher than in Group G, which had received two of three i.m. injections (17.6 IU l-1; P < 0.01, P < 0.05). In the group which received four 2 micrograms i.d. inoculations, the level was higher than in Group G in month 7, but lower in month 12. It was concluded that three i.d. inoculations, each of 4 micrograms, may be used to obtain high antibody levels within a short period of time. However, it is recommended that a 10 micrograms i.m. injection in month 6 is applied as a booster. Consequently, we could not present an economic and effective low-dose intradermal inoculation method. PMID- 9364691 TI - Immunization of seronegative infants with hepatitis A vaccine (HAVRIX; SKB): a comparative study of two dosing schedules. AB - Hepatitis A virus (HAV) infection is of public health significance among infants and diapered children. Although two licensed HAV vaccines are available, they have not been assessed widely in children under the age of 2 years and are not currently licensed for this age group. The purpose of this study was to evaluate the immunogenicity and reactogenicity of HAV vaccine in seronegative infants. Fifty-three healthy infants were immunized with 360 ELISA Units (EL.U.) of an inactivated HAV vaccine at 2, 4, and 6 (Group 1) or 2, 4, and 15 months of age (Group 2). These injections were not received on the same day that participants received their routine childhood immunizations. HAV serum antibodies were detected using a modified radioimmunoassay procedure and concentrations were calculated using a World Health Organization serum anti-HAV reference standard. No serious-systemic or local reactions were noted among the immunized infants. Three months following the third immunization, seroconversion rates were 100% and 93% in groups 1 and 2, respectively. No significant differences were observed in the geometric mean anti-HAV concentrations between the two groups at comparable time points, i.e. 2 months after the second dose, 3 months after the third dose, and 19 months after the first dose. Three infants, not included in the data presented above, had preexisting maternal antibodies; one never responded to the vaccine and the other two did not respond until maternal antibody levels had become reduced. The results indicate that the inactivated HAV vaccine is highly immunogenic in seronegative infants and could be included in the routine harmonized infant immunization schedule. PMID- 9364694 TI - Protection against Schistosoma mansoni infection with a recombinant baculovirus expressed subunit of calpain. AB - Infections by human schistosomes, in particular Schistosoma mansoni, account for significant morbidity and mortality every year in tropical and sub-tropical areas. The eggs of the parasite induce pathological changes in the infected host; in chronic and heavy infections, these changes may lead to death. A well-designed anti-schistosomal vaccine, alone or in concert with existing control measures such as chemotherapy, may prove to be a safe, inexpensive, and effective means of reducing the occurrence of severe disease and death in S. mansoni infection. Previous studies have demonstrated the importance of the syncytial layer containing the apical plasma membrane (APM) of S. mansoni in both the survival of the parasite in the mammalian host and as a potential source of immunogens which may be utilized as vaccine candidates. In this paper, we present evidence for the protective capacity of several schistosomal antigen preparations, including a calcium binding protein of the APM, S. mansoni calpain (GenBank accession no. M74233). We have constructed and characterized expression of a recombinant baculovirus expressing the large subunit of S. mansoni calpain, Sm-p80. This recombinant Sm-p80 is recognized by IgA, IgM, IgG1, and IgG3 isotype antibodies found in S. mansoni-infected human sera and partially-purified recombinant Sm-p80 provided a 29-39% reduction in worm burden in immunized mice challenged with S. mansoni. Our data indicate that Sm-p80 may be a useful vaccine antigen for the reduction of the morbidity associated with S. mansoni infections of mammalian hosts. PMID- 9364693 TI - Ten-year neonatal hepatitis B vaccination program, The Netherlands, 1982-1992: protective efficacy and long-term immunogenicity. AB - From 1982 to 1989, 705 infants born to HBsAg-positive mothers entered the Dutch neonatal hepatitis B vaccination program and received passive-active hepatitis B immunization in three randomized controlled trials testing variations in time of starting active vaccination, dose and type of vaccine, and number of hepatitis B immunoglobulin (HBIg) injections. A meta-analysis of individual patient data of the three randomized trials was performed to determine which independent host and vaccination related factors influence protective efficacy and long-term immunogenicity, and to assess whether hepatitis B vaccination concomitant with standard DKTP vaccination provides optimal protection. Statistical methodology included multivariate logistic regression analysis. Eight infants (1.1%), all born to HBeAg-positive mothers, became HBsAg carriers within the first year of life. The protective efficacy rate (PER) of passive-active immunization at 12 months follow-up was 92% for the total group of children from 114 HBeAg-positive mothers with no significant differences between children starting active immunization at birth or at 3 months of age, between infants starting at 3 months of age receiving one or two doses of HBIg or between those receiving plasma derived or recombinant vaccine. The only factor that affected the PER significantly was the level of maternal HBV DNA; PER was 100% if maternal HBV DNA was < 150 pg ml-1 and 68% for HBV DNA levels > 150 pg ml-1. After 5 years of follow-up, the group that started active immunization at birth had significantly more infants with loss of seroprotection (anti-HBs levels < 10 IU l-1, 15%) than the corresponding group starting at 3 months of age (anti-HBs < 10 IU l-2, 2%). One of 35 children with loss of seroprotection at 2 years became a HBsAg carrier in the fifth year of follow-up. This meta-analysis shows that the protective efficacy of passive-active hepatitis B vaccination is mainly influenced by material HBV DNA levels, and independent of the time of starting active vaccination at birth or at 3 months of age; long-term immunity was enhanced by starting active vaccination concomitant with DKTP vaccination. These findings allow incorporation of hepatitis B vaccine into the standard infant immunization programs for countries with a passive-active immunization strategy for the control of hepatitis B. Additional measures are needed to protect neonates of highly viremic women. PMID- 9364695 TI - Biophysical and antigenic characterization of gonococcal protein I incorporated into liposomes. AB - The major gonococcal outer membrane protein, protein I (Por), was reconstituted into liposomes composed of either 1-palmitoyl, 2-oleoyl phosphatidylcholine (POPC) or POPC:1-palmitoyl, 2-oleoyl phosphatidylethanolamine (POPE) (1:1 weight ratio) and the resulting proteoliposomes characterized with respect to their biophysical and antigenic properties. Isopycnic density gradient centrifugation studies established that essentially all of the protein was reconstituted into the lipid bilayer with no significant differences in incorporation seen as a function of lipid composition. Examination of Por orientation in these proteoliposomes revealed that over 80% of the protein was oriented facing outwards in the same 'hairpin loop' fashion found in the native bacterial membrane. Reconstituted Por proteoliposomes exhibited a mean vesicle diameter of > 0.5 micron but could be reduced by extrusion without significant loss of protein or lipid. These extruded systems were suitable for sterilization by terminal filtration. The antibody binding activities of various Por liposome formulations were determined using both anti-Por monoclonal antibodies and an immunized rabbit sera. No significant differences in antibody binding were observed as a function of proteoliposome lipid composition. However, consistently higher levels of antibody binding were obtained for Por liposomes prepared in this way compared with reconstituted systems prepared as described in earlier publications. PMID- 9364696 TI - Vaccination against hepatitis B virus in Spain: a cost-effectiveness analysis. AB - A cost-effectiveness analysis was made to determine the effectiveness of the following strategies of mass immunization with the new recombinant vaccine against the hepatitis B virus in Spain: vaccination of adolescents, newborns, both populations, and vaccination plus passive immunization of newborns of HBsAg positive mothers. Decision trees supported on Markov models with Monte Carlo simulation have been used for the calculation of costs of the disease, and a mathematical model of differential equations was used for the simulation of the potential effectiveness of vaccination. The costs considered were those associated with the vaccination and travel of subjects, diagnosis, and treatment of the disease. The results are presented as additional cost or saving per case of infection prevented. In all assumptions, results showed that the most effective strategy for mass vaccination was the combination of vaccinating all adolescents together with active and passive immunization of children born to HBsAg positive mothers. PMID- 9364697 TI - A recombinant prime, peptide boost vaccination strategy can focus the immune response on to more than one epitope even though these may not be immunodominant in the complex immunogen. AB - Rhesus monkeys were successfully vaccinated using a strategy of priming with a candidate envelope subunit vaccine and boosting with synthetic peptides. Priming was carried out with recombinant HIV-1 SF2 envelope glycoprotein incorporated into ISCOMs, following the attachment of a lipid tail. Peptides, covalently linked to ISCOMs, representing linear sequences with the V2 and V3 regions, were used to boost functional antibodies-to neutralizing epitopes in both of these regions. Injections with these peptide formulations substantially increased the titre of serum neutralizing antibodies from low or undetectable levels. In addition to completely neutralizing the homologous HIV-1 SF2 strain, these sera also neutralized the escape variant, HIV-1 SF13. However, no antibodies were boosted which could compete with human, neutralizing monoclonal antibodies recognising conformational epitopes. The peptides also boosted antibodies to a peptide whose sequence lies close to the V2 region neutralizing epitope but does not overlap with it. Importantly, the level of antibodies to an unrelated epitope associated with enhancement of HIV-1 SF13 continued to fall after the peptide boost. Successful protection against challenge with chimeric simian immunodeficiency virus expressing HIV-1 SF13 envelope glycoproteins (SHIV SF13) may be due to an increase in the ratio of neutralizing to enhancing antibodies by selectively boosting with peptides to critical neutralizing epitopes. PMID- 9364698 TI - Vaccination of natural reservoir hosts with recombinant lipidated OspA induces a transmission-blocking immunity against Lyme disease spirochaetes associated with high levels of LA-2 equivalent antibodies. AB - As observed in humans, immune responses in naturally infected reservoir hosts of Borrelia burgdorferi sensu lato rarely target the outer surface proteins (Osp) A and B of Lyme disease spirochaetes. The absence of protective immunity in such hosts following tick-borne infection allows them to play an effective role in the maintenance of Lyme borreliosis in nature. Therefore, the question was addressed whether one of the most prominent natural reservoir host species of B. burgdorferi s.l. in Europe, the yellow-necked mouse (Apodemus flavicollis), may lack the ability to elicit transmission-blocking antibodies to Lyme borreliosis spirochaetes. Yellow-necked mice were immunized with a recombinant lipidated OspA from B. burgdorferi sensu stricto or with high numbers of UV-irradiated whole spirochaetes. All immunized mice, but not untreated controls, developed polyclonal humoral immune responses to OspA (31 kDa). Serum antibodies of animals vaccinated with the recombinant OspA contained high levels of antibody to an epitope of OspA, defined by the monoclonal antibody LA-2, whereas only low levels of LA-2 equivalent antibodies could be detected in sera from animals immunized with killed spirochaetes. Ixodes ricinus ticks infected with B. burgdorferi s.s. lost their spirochaete load after feeding on animals with high levels of LA-2 equivalent antibody; ticks feeding on animals which had only low or undetectable serum levels of LA-2 equivalent antibodies retained their spirochaete infection. Furthermore, animals with high levels of LA-2 equivalent antibody were protected against spirochaete infection. Our study shows that natural mouse reservoir hosts are highly competent to generate transmission-blocking antibodies after vaccination with a lipidated recombinant OspA and indicates that antibodies to the LA-2 epitope play a key role in the destruction of B. burgdorferi s.s. within feeding Ixodes ricinus ticks. PMID- 9364699 TI - Immunogenicity of trivalent subunit versus virosome-formulated influenza vaccines in geriatric patients. AB - The safety and immunogenicity of a commercial trivalent subunit influenza vaccine and an experimental virosome-formulated influenza vaccine were evaluated among geriatric patients in a double-blind, randomized manner. The virosome vaccine was produced by incorporating hemagglutinin (HA) into the membrane of liposomes composed of phosphatidylcholine. Both vaccines elicited a significant (P < 0.01) rise in the geometric mean anti-HA antibody titer to all three vaccine components 1 month after immunization. However, significantly (P < 0.005) more subjects vaccinated with the virosome preparation mounted a more than fourfold rise to the A/Singapore and A/Beijing strains compared with those who received subunit vaccine. The percentage of patients who attained protective levels (anti-HA titer > or = 40) of anti-A/Beijing antibody was also significantly (P < 0.005) higher in the virosome group. Subjects who possessed non-protective baseline antibody levels to the A/Singapore and A/Beijing strains were more likely (P < 0.005 0.030) to achieve protective levels after immunization with the virosome vaccine than with the subunit vaccine. Of particular clinical significance was the fact that 68.4% of subjects immunized with the virosome vaccine attained protective levels of antibody to all three vaccine components versus 38% for the subunit vaccine (P = 0.010). PMID- 9364700 TI - Feasibility study of a combined diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HBV) vaccine, and comparison of clinical reactions and immune responses with diphtheria-tetanus-acellular pertussis (DTPa) and hepatitis B vaccines applied as mixed or injected into separate limbs. AB - The feasibility of a combined diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HBV) vaccine was assessed and a comparison made of immunogenicity and reactogenicity to DTPa and HBV vaccines mixed in one syringe and to concomitant but separate injections as a primary vaccination course in three groups of infants at 3, 4.5 and 6 months of age. All subjects attained protective levels of anti-HBs antibodies 1 month after the primary course with higher geometric mean titres (GMTs) in the combined or mixed vaccinations. GMTs for pertussis toxin (PT), filamentous haemagglutinin (FHA) and pertactin (PRN) were as good or better in the groups administered the combined formulation and the extemporaneously mixed vaccines than the separate administration. No serious adverse event related to the vaccination was reported in this study. Neither the combined formulation of DTPa and HBV vaccines nor the extemporaneous mixture increased the incidence or severity of adverse reactions compared with the separate administration of DTPa. This study shows the feasibility of a combined DTPa-HBV vaccine and the data support, in the interim, the mixing of DTPa and HBV vaccines which are tested in clinical trials for infant immunization. PMID- 9364701 TI - DNA vaccination with cytokine fusion constructs biases the immune response to ovalbumin. AB - DNA vaccination may work through direct transfection of antigen presenting cells (APC), or by secretion of the encoded protein by muscle or skin cells for uptake by APC. If cytokines are attached to the antigen, they may influence APC or responding T cells to drive the response toward a Th1 or Th2 direction, and/or potentiate it in an antigen-specific manner. To test this concept, expression vectors were constructed containing the ovalbumin (OVA) gene either alone, or linked to cytokine genes including GM-CSF, IFN-gamma, IL-2, IL-4, IL-12, or a sequence encoding nine amino acids of IL-1 beta. These constructs expressed OVA cytokine fusion proteins in vitro which retained cytokine bioactivity. C57BL/6 mice were injected intramuscularly with the DNA constructs. Little if any OVA specific antibody was produced in response to any of the DNA constructs, except for OVA-IL-4. However, lymphocytes from BALB/c mice vaccinated with OVA-IL-12 and OVA-IL-1 beta constructs produced more IFN-gamma and less IL-4 during in vitro restimulation assays than did other groups. All constructs elicited OVA-specific cytotoxic responses which were maintained or even increased over 16 weeks. The OVA-IL-12 and OVA-IL-1 beta peptide constructs elicited the strongest cytotoxic responses at 2 weeks postinjection. Cytotoxic responses were seen in all animals, even those lacking OVA-specific Ab, and were not related to Ab level. These studies indicate that the humoral, cytokine, and cytotoxic responses to DNA vaccination can be effectively altered by certain cytokine fusion constructs. PMID- 9364702 TI - Free radical induced polymerization of synthetic peptides into polymeric immunogens. AB - Free radical induced polymerization of vinyl monomers such as the acryloyl peptides described here is a facile and rapid reaction used routinely, for example, in the polymerization of acrylamide and bisacrylamide for the assembly of polyacrylamide gels. The technology allows the incorporation of many of the same or different peptide determinants into a single polymer chain. In this study large polymers containing multiple copies of peptides representing T- and B-cell determinants of influenza haemagglutinin were constructed. The determinants retained antigenicity after the polymerization procedure and the polymers were highly immunogenic; the levels of antibody obtained after a single dose of polymeric immunogen were at least as great as those achieved only after repeated doses of the equivalent monomeric peptide. The technology has a wide range of potential applications, not the least significant of which is the construction of designer immunogens for third generation vaccine candidates. PMID- 9364703 TI - Government to assess alternatives to quarantine. PMID- 9364704 TI - Food hygiene--can the profession deliver? PMID- 9364705 TI - Outbreak off canine distemper in vaccinated dogs in Finland. AB - Canine distemper reappeared in dogs in Finland in 1990 after a 16-year absence. In 1994 to 1995 an outbreak occurred in areas with a high density dog population which involved dogs vaccinated against distemper. The estimated total number of cases was at least 5000, and 865 cases were confirmed by indirect fluorescent antibody testing of 3649 epithelial cell samples. The signs recorded by veterinary clinicians ranged from conjunctivitis, pyrexia and anorexia to signs of respiratory and gastrointestinal illness, with an estimated mortality of 30 per cent. Of the confirmed cases 631 (73 per cent) were between three and 24 months of age; 487 of these had been vaccinated at least once and 351 (41 per cent) had a complete vaccination history. Of these 351 fully vaccinated animals the proportion of dogs vaccinated with the most popular vaccine was significantly higher than would have been expected by its market share. In total, 4676 serum samples were collected from healthy vaccinated dogs during the peak and decline of the outbreak and tested for the presence of virus neutralising antibodies. The decrease in the proportion of young dogs with antibody titres < 1/8 coincided with the decline and end of the outbreak during the spring and summer of 1995. It was concluded that a critical decrease in the population's immunity during 1990 to 1994 was a major reason for the outbreak in the summer of 1994 and that the ultimate test for vaccines is an outbreak of disease. PMID- 9364706 TI - Comparative studies of ivermectin and moxidectin in the control of naturally acquired cyathostome infections in horses. AB - The control of naturally acquired cyathostome infections in horses by treatments with ivermectin and moxidectin was evaluated in three field studies. In a first study the efficacy of both drugs was assessed in a faecal egg count reduction test. Both ivermectin and moxidectin demonstrated efficacies greater than 99 per cent for up to 60 days after treatment. In a second study, the period required for strongyle eggs to reappear was estimated in horses treated either with ivermectin or moxidectin. For the horses treated with ivermectin the period varied between 10 and approximately 13 weeks, and for moxidectin between 22 and approximately 24 weeks. With both drugs strongyle eggs started to reappear in the faeces significantly earlier in foals and young horses than in adults. In a third study, two prophylactic dosing schemes involving three ivermectin treatments at intervals of eight weeks, and two moxidectin treatments 12 weeks apart, were found to be highly effective in controlling strongyle infections of horses on pasture. PMID- 9364708 TI - Uterine T cell lymphoma in a mare, with multicentric involvement. PMID- 9364707 TI - Double-labelling immunohistochemical study of megakaryocytes in African swine fever. AB - Bone marrow samples from pigs infected with the highly virulent Malawi'83 or moderately virulent Dominican Republic (DR'78) isolates of African swine fever virus were studied by means of a double labelling immunohistochemical technique which stained the major structural protein VP73 of the virus and megakaryocytes simultaneously. In pigs infected with the highly virulent Malawi'83 isolate, 2.2 per cent of megakaryocytes were VP73+ five days after inoculation, and at six and seven days 2.5 and 9.5 per cent of megakaryocytes were VP73+. Some infected and uninfected megakaryocytes showed pyknosis and karyorrhexis, particularly at seven days after inoculation. However, in comparison with uninfected pigs, the number of megakaryocytes decreased only at seven days after inoculation. In pigs infected with the moderately virulent DR'78 isolate, only 0.2 per cent of megakaryocytes were VP73+ at eight days after inoculation. However, at eight, nine and 10 days after inoculation the total number of megakaryocytes was significantly lower (P < 0.01) than in control uninfected pigs, and the majority of the megakaryocytes showed signs of cell death such as pyknosis and karyorrhexis. The fact that this greater destruction of megakaryocytes was associated with the lower rate of infection of this cell type suggests that indirect damage to megakaryocytes is an additional mechanism of thrombocytopenia in acute and subacute African swine fever. PMID- 9364709 TI - Use of doramectin against experimental infections of cattle with Dictyocaulus viviparus. PMID- 9364710 TI - Use of animals in research. PMID- 9364712 TI - Use of carprofen in racehorses. PMID- 9364713 TI - Lameness and foot lesions in adult British dairy goats. AB - In the first population-based study of lameness and foot lesions in adult goats in the UK, a random sample of 307 adult goats from four large commercial dairy farms was examined. The overall proportion of lame goats was 9.1 per cent (2.6 to 24.4 per cent). The abnormalities detected were horn separation (29.6 per cent), white line lesions (13.0 per cent) slippering (10.1 per cent), abscess of the sole (4.2 per cent), foreign body, and granulomatous lesions (1.0 per cent). Between 83.1 and 95.5 per cent of the goats had overgrown horn on at least one foot. The number of feet of individual goats with horn separation followed a Poisson distribution suggesting that it was associated with environmental rather than genetic or nutritional factors. Horn separation, abscess of the sole and footrot were significantly associated with lameness, but white line lesions, slippering and granulomatous lesions were not. There were differences between the farms in the prevalence of lameness and foot lesions. Routine foot trimming was associated with a lower prevalence of lameness. PMID- 9364714 TI - Lumbar myelography in 79 dogs, using different puncture sites. AB - Lumbar myelography was performed in 79 dogs either before spinal surgery or as part of an investigation of neurological disease. In small dogs the site of the puncture was between L1 and L5, avoiding the lumbosacral intumescence, whereas in large dogs the site was between T13 and L2. It was found that a lumbar puncture cranial to the lumbar intumescence was easier and caused no problems. The lumbar puncture was unsuccessful in three obese dogs. In 72 per cent of the cases the myelogram revealed a lesion, and the main cause of a non-diagnostic myelogram was epidural leakage. PMID- 9364716 TI - Persistent activity of injectable ivermectin against important gastrointestinal nematodes of sheep. PMID- 9364715 TI - Treatment of porcine cysticercosis with oxfendazole: a dose-response trial. AB - Taenia solium cysticercosis is an important public health problem in developing countries. Oxfendazole has been shown to be highly effective against porcine cysticercosis, when given as a single dose at 30 mg/kg bodyweight. This dose, however, was estimated from experience with albendazole. A controlled dose response trial was therefore undertaken to determine the efficacy and safety of three concentrations of oxfendazole. Twenty-four naturally parasitised pigs were divided into four groups and treated with oxfendazole at 10 mg/kg, 20 mg/kg or 30 mg/kg, or left untreated. Eight to 10 weeks later the pigs were killed and the viability of the parasites assessed by evagination. No side-effects of oxfendazole treatment were observed. In the control group more than 90 per cent of the cysts were viable. Viable cysts were found in the muscle and brain of the pigs treated with 10 or 20 mg/kg oxfendazole. At 30 mg/kg there were no viable cysts in any of the tissues examined, indicating that this concentration of oxfendazole provided an effective treatment against porcine cysticercosis. PMID- 9364718 TI - Transmissible gastroenteritis of pigs. PMID- 9364717 TI - Absence of Chlamydia as an aetiological factor in aborting mares. PMID- 9364719 TI - Endogenous opiates in the chick retina and their role in form-deprivation myopia. AB - In this study, the possible role of the retinal enkephalin system in form deprivation myopia (FDM) in the chick eye was investigated. Daily intravitreal injection of the nonspecific opiate antagonist naloxone blocked development of FDM in a dose-dependent manner, while injection of the opiate agonist morphine had no effect at any dose tested. The ED50 for naloxone (calculated maximum concentration in the vitreous) was found to be in the low picomolar range. The results using receptor-subtype-specific drugs were contradictory. Drugs specific for mu and delta receptors had no effect on FDM. The kappa-specific antagonist nor-binaltorphimine (nor-BNI) reduced FDM by about 50% at maximum daily retinal doses ranging between 4 x 10(-10) and 4 x 10(-7) M, while the kappa-specific agonist U50488 blocked FDM in a dose-dependent manner with an ED50 between 5 x 10(-8) and 5 x 10(-7) M. Met-enkephalin immunoreactivity (ME-IR) was localized immunocytochemically to a subset of amacrine cells (ENSLI cells) and their neurites in the inner plexiform layer (IPL). As reported previously, ENSLI cells from untreated chick retinas showed a cyclical pattern of immunoreactivity, with increased immunoreactivity in the light compared to the dark. Form-deprivation did not appear to change this pattern. Amounts of preproenkephalin mRNA from normal or form-deprived eyes were approximately the same under all conditions. Daily injection of naloxone, however, did increase ME-IR in the dark. These results suggest that naloxone may affect release of enkephalin from the ENSLI cells. The results as presented are inconclusive with regards to the role of the enkephalin system in FDM. While the kappa receptor may participate, there is no conclusive evidence here for a direct effect of opiate receptors. The effect of naloxone on form-deprived eyes may be due to its effect on release of peptides from the ENSLI cells. PMID- 9364720 TI - Large retinal ganglion cells in the pipid frog Xenopus laevis form independent, regular mosaics resembling those of teleost fishes. AB - Population-based studies of retinal neurons have helped to reveal their natural types in mammals and teleost fishes. In this, the first such study in a frog, labeled ganglion cells of the mesobatrachian Xenopus laevis were examined in flatmounts. Cells with large somata and thick dendrites could be divided into three mosaic-forming types, each with its own characteristic stratification pattern. These are named alpha a, alpha ab, and alpha c, following a scheme recently used for teleosts. Cells of the alpha a mosaic (approximately 0.4% of all ganglion cells) had very large somata and trees, arborizing diffusely within sublamina a (the most sclerad). Their distal dendrites were sparsely branched but achieved consistent coverage by intersecting those of their neighbors. Displaced and orthotopic cells belonged to the same mosaic, as did cells with symmetric and asymmetric trees. Cells of the alpha ab mosaic (approximately 1.2%) had large somata, somewhat smaller trees that appeared bistratified at low magnification, and dendrites that branched extensively. Their distal dendrites arborized throughout sublamina b and the vitread part of a, tessellating with their neighbors. All were orthotopic; most were symmetric. Cells of the alpha c mosaic (approximately 0.5%) had large somata and very large, sparse, flat, overlapping trees, predominantly in sublamina c. All were orthotopic; some were asymmetric. Nearest-neighbor analyses and spatial correlograms confirmed that each mosaic was regular and independent, and that spacings were reduced in juvenile frogs. Densities, proportions, sizes, and mosaic statistics are tabulated for all three types, which are compared with types defined previously by size and symmetry in Xenopus and potentially homologous mosaic-forming types in teleosts. Our results reveal strong organizational similarities between the large ganglion cells of teleosts and frogs. They also demonstrate the value of introducing mosaic analysis at an early stage to help identify characters that are useful markers for natural types and that distinguish between within-type and between-type variation in neuronal populations. PMID- 9364721 TI - The origin of slow PIII in frog retina: current source density analysis in the eyecup and isolated retina. AB - The objective of this research was to determine the sources and sinks of current underlying the slow PIII component of the electroretinogram. Current source density analysis of the ERG evoked by diffuse light flashes was performed in eyecup and isolated retinas of frog. Blockade of synaptic transmission with aminophosphonobutyric + kynurenic acids simplified the CSD profiles through the retina. In addition to the photoreceptor source/sink pair, there was evidence for a major slow PIII source near the outer limiting membrane, a major sink near the inner limiting membrane, and a small source near the inner plexiform layer. Addition of Ba2+ abolished the slow PIII source/sinks, and it left only the photoreceptor source and sink. The results support the idea that slow PIII originates through K+ spatial buffering by Muller cells. Specifically, the light evoked decrease in [K+]o in the subretinal space causes a primary K+ efflux from Muller cells (current source) and a primary K+ influx at the Muller cell endfeet (current sink). A decrease in [K+]zero in the proximal retina, caused by diffusion of K+ to the subretinal space, results in K+ efflux (the current source) at the inner plexiform layer. PMID- 9364722 TI - Immunohistochemical analysis of the neurotrophins BDNF and NT-3 and their receptors trk B, trk C, and p75 in the developing chick retina. AB - The neurotrophins are trophic and mitogenic factors critical for the development of specific classes of neurons in the central and peripheral nervous systems. In the retina, BDNF and NT-3 have been shown to promote the survival of differentiated ganglion cells (Rodriguez-Tebar et al., 1989; De La Rosa et al., 1994). NT-3 has also been demonstrated to support the survival of amacrine cells and facilitates the differentiation of retinal neurons in culture (De La Rosa et al., 1994). Here, we examine immunohistochemically the expression of BDNF and NT 3 proteins, their cognate receptors, trk B and trk C, respectively, and the p75 neurotrophin receptor in the developing chick retina. At E8, the earliest stage of retinal development examined, all of these proteins exhibit diffuse expression throughout the width of the retina, with the strongest reactivity in the innermost layers. A gradual restriction in expression to ganglion cells and amacrine cells, the staining of which is most prominent at E15, is followed by a downregulation of expression with the strongest immunoreactivity persisting in the ganglion cell layer. Overlapping patterns of expression throughout embryonic development indicate a colocalization of the neurotrophins and their receptors, although NT-3 and p75 alone are present in the inner plexiform layer and only p75 is observed in the outer plexiform layer. Although some of the immunoreactivity for BDNF, NT-3, and their receptors in retina may reflect trophic mechanisms operating in association with the optic tectum and isthmo-optic nucleus, the colocalization of ligands and receptors in retina strengthens the assertion that these neurotrophins function locally during development. PMID- 9364723 TI - A comparison of GABAC and rho subunit receptors from the white perch retina. AB - There is increasing evidence that GABAC receptors are composed of GABA rho subunits. In this study, we compared the properties of native GABAC receptors with those of receptors composed of a GABA rho subunit. A homologue of the GABA rho gene was cloned from a white perch (Roccus americana) retinal cDNA library. The clone (perch-s) has an open reading frame of 1422 nucleotide base pairs and encodes a predicted protein of 473 amino acids. It is highly homologous to GABA rho subunits cloned from human and rat retinas. The receptors (perch-s receptor) expressed by this gene in Xenopus oocytes show properties similar to those of the GABAC receptors present on white perch retinal neurons. GABA induced a sustained response that had a reversal potential of -27.1 +/- 3.6 mV. The EC50 for the response was 1.74 +/- 1.25 microM, a value similar to that reported for GABAC receptors. Pharmacologically, the responses were bicuculline insensitive and not modulated by either diazepam or pentobarbital as is the case for GABAC receptors. There were, however, some distinct differences between native GABAC and perch-s receptors. I4AA acts as a partial agonist on perch-s receptors whereas it is strictly an antagonist on native GABAC receptors. Picrotoxin inhibition is noncompetitive on perch-s receptors, but both competitive and noncompetitive on GABAC receptors. We conclude that GABAC receptors are formed by GABA rho subunits but that native GABAC receptors probably consist of a mixture of GABA rho subunits. PMID- 9364724 TI - Single-neuron activity in the dorsomedial frontal cortex during smooth-pursuit eye movements to predictable target motion. AB - A region of dorsomedial frontal cortex (DMFC) has been implicated in planning and executing saccadic eye movements; hence it has been referred to as a supplementary eye field (SEF). Recently, activity related to executing smooth pursuit eye movements has been recorded from the DMFC, and microstimulation here has been shown to evoke smooth eye movements. This report documents neuronal activity present in smooth-pursuit tasks where the predictability of target motion was manipulated. The activity of many neurons in the DMFC reached a peak when a predictable change in target motion occurred. Furthermore, the peak activity of some cells was systematically shifted by manipulating the duration of the target event, indicating that the network these neurons were in could learn the temporal characteristics of new target motion. Finally, the activity of most neurons tested was greater when target motion was predictable than when it was unpredictable. The results suggest that the DMFC participates in planning smooth pursuit eye movements based on past stimulus history. PMID- 9364725 TI - Specialized neuropeptide Y- and glucagon-like immunoreactive amacrine cells in the peripheral retina of the turtle. AB - There are many regional differences in cell morphology and neurochemistry in the retina. This study examined a specialized population of neuropeptide Y- and glucagon-like immunoreactive amacrine cells in the peripheral retina of the turtle. Some of the dendritic processes from these peptidergic amacrine cells formed a dense circumferentially oriented nerve fiber plexus which ran parallel to the ora serrata. Collaterals from this plexus projected into and innervated the nonpigmented ciliary epithelium in the pars plana region of the ciliary body. Electron microscopy revealed that the neuropeptide Y- and glucagon-like immunoreactive processes in the ciliary epithelium contained many labeled, large dense-cored vesicles. Small crystals of lipid-soluble fluorescent dye were implanted in the retina near the ora serrata in fixed retinal tissue to search for other peripheral retinal specializations. Numerous thick and thin cell processes oriented parallel to the ora serrata were labeled in the retina by the dye. In addition, many dye-labeled somata with circumferentially oriented dendritic arborizations were seen in the extreme periphery of the retina. Many of these dye-labeled cells and processes were clearly not associated with the neuropeptide Y- and glucagon-like immunoreactive cells described above. This study has shown that some peptidergic neurons in the peripheral retina have a unique morphology in comparison to more centrally located cells. The function of these specialized peripheral cells is not established, but the innervation of the ciliary epithelium by peptidergic amacrine cells suggests that they may be involved in control of aqueous inflow. PMID- 9364726 TI - Neuronal responses in extrastriate cortex to objects in optic flow fields. AB - During locomotion, observers respond to objects in the environment that may represent obstacles to avoid or landmarks for navigation. Although much is known about how visual cortical neurons respond to stimulus objects moving against a blank background, nothing is known about their responses when objects are embedded in optic flow fields (the patterns of motion seen during locomotion). We recorded from cells in the lateral suprasylvian visual area (LS) of the cat, an area probably analogous to area MT. In our first experiments, optic flow simulations mimicked the view of a cat trotting across a plain covered with small balls; a black bar lying on the balls served as a target object. In subsequent experiments, optic flow simulations were composed of natural elements, with target objects representing bushes, rocks, and variants of these. Cells did not respond to the target bar in the presence of optic flow backgrounds, although they did respond to it in the absence of a background. However, 273/423 cells responded to at least one of the taller, naturalistic objects embedded in optic flow simulations. These responses might represent a form of image segmentation, in that cells detected objects against a complex background. Surprisingly, the responsiveness of cells to objects in optic flow fields was not correlated with preferred direction as measured with a moving bar or whole-field texture. Because the direction of object motion was determined solely by receptive-field location, it often differed considerably from a cell's preferred direction. About a quarter of the cells responded well to objects in optic flow movies but more weakly or not at all to bars moving in the same direction as the object, suggesting that the optic flow background modified or suppressed direction selectivity. PMID- 9364727 TI - Visual cortex neurons in monkeys and cats: detection, discrimination, and identification. AB - A descriptive function method was used to measure the detection, discrimination, and identification performance of a large population of single neurons recorded from within the primary visual cortex of the monkey and the cat, along six stimulus dimensions: contrast, spatial position, orientation, spatial frequency, temporal frequency, and direction of motion. First, the responses of single neurons were measured along each stimulus dimension, using analysis intervals comparable to a normal fixation interval (200 ms). Second, the measured responses of each neuron were fitted with simple descriptive functions, containing a few free parameters, for each stimulus dimension. These functions were found to account for approximately 90% of the variance in the measured response means and response standard deviations. (A detailed analysis of the relationship between the mean and the variance showed that the variance is proportional to the mean.) Third, the parameters of the best-fitting descriptive functions were utilized in conjunction with Bayesian (optimal) decision theory to determine the detection, discrimination, and identification performance for each neuron, along each stimulus dimension. For some of the cells in monkey, discrimination performance was comparable to behavioral performance; for most of the cells in cat, discrimination performance was better than behavioral performance. The behavioral contrast and spatial-frequency discrimination functions were similar in shape to the envelope of the most sensitive cells; they were also similar to the discrimination functions obtained by optimal pooling of the entire population of cells. The statistics which summarize the parameters of the descriptive functions were used to estimate the response of the visual cortex as a whole to a complex natural image. The analysis suggests that individual cortical neurons can reliably signal precise information about the location, size, and orientation of local image features. PMID- 9364728 TI - Spectral sensitivity of macaque monkeys measured with ERG flicker photometry. AB - Macaque monkeys are widely used as a model species for investigations of the biology of human vision. Previous measurements suggest that the cone-based spectral sensitivity of these two primates is greatly similar, but perhaps not identical. We measured the photopic spectral sensitivity of 42 male macaque monkeys from two species (Macaca mulatta, M. fascicularis) using an objective index, electroretinogram flicker photometry. The variations among individuals and between the two species were very small and there was no evidence for any significant cone pigment polymorphism in this sample. There are small but systematic differences in spectral sensitivity between macaque monkeys and equivalently tested human subjects--the monkeys were slightly more sensitive to short wavelengths (< 520 nm) and slightly less sensitive to wavelengths longer than this value. The results obtained from the curve fitting of standard photopigment absorption spectra to the spectral-sensitivity functions suggest that the difference between human and macaque monkey spectral sensitivity principally reflects differences in the relative proportions of the long- and middle-wavelength cones in the retinas of the two species. PMID- 9364729 TI - Alternating monocular exposure increases the spacing of ocularity domains in area 17 of cats. AB - Goodhill (1993) has recently suggested that the spacing of ocularity domains in visual cortex is not solely an intrinsic property of cortex, but is determined, at least in part, by the degree of correlation in the activity of the two eyes. In support of this model, Lowel (1994) has shown that strabismus, which decorrelates the activity of the two eyes, increases the spacing of ocular dominance columns in area 17, but not area 18, of the cat. As a further test of Goodhill's model, in this paper we examine the effects of another rearing procedure that decorrelates the activity of the two eyes, namely alternating monocular exposure (AME). Cats were reared either normally (9 cats) or with AME (21 cats). We labeled their ocularity domains by one of three methods: ocular dominance columns by 2-deoxyglucose (14 cats), and ocular dominance patches by transneuronal transport (14 cats), or by injections of tracer into single layers of the lateral geniculate nucleus (LGN; 2 cats). The spacing of ocular dominance was 11% greater in the AME cats than in the normal cats (0.976 vs. 0.877 mm). These results are similar to those previously reported for strabismic cats, although the effect is less striking. We thus confirm that decorrelating the activity of the two eyes increases the spacing of cortical ocularity domains. Our results further suggest that the degree of decorrelation affects the extent of that increase. PMID- 9364731 TI - Neuronal responses to edges defined by luminance vs. temporal texture in macaque area V1. AB - We examined the responsivity, orientation selectivity, and direction selectivity of a sample of neurons in cortical area V1 of the macaque using visual stimuli consisting of drifting oriented contours defined by each of two very different figural cues: luminance contrast and temporal texture. Comparisons of orientation and direction tuning elicited by the different cues were made in order to test the hypothesis that the neuronal representations of these parameters are form-cue invariant. The majority of the sampled cells responded to both stimulus types, although responses to temporal texture stimuli were generally weaker than those elicited by luminance-defined stimuli. Of those units exhibiting orientation selectivity when tested with the luminance-defined stimuli, more than half were also selective for the orientation of the temporal texture stimuli. There was close correspondence between the preferred orientations and tuning bandwidths revealed with the two stimulus types. Of those units exhibiting directional selectivity when tested with the luminance-defined stimuli, about two-thirds were also selective for the direction of the temporal texture stimuli. There was close correspondence between the preferred directions revealed with the two stimulus types, although bidirectional responses were somewhat more common when temporal texture stimuli were used. These results indicate that many V1 neurons encode orientation and direction of motion of retinal image features in a manner that is largely independent of whether the feature is defined by luminance or temporal texture contrast. These neurons may contribute to perceptual phenomena in which figural cue identity is disregarded. PMID- 9364732 TI - Intracortical connections are not required for oscillatory activity in the visual cortex. AB - Synchronized oscillatory discharge in the visual cortex has been proposed to underlie the linking of retinotopically disparate features into perceptually coherent objects. These proposals have largely relied on the premise that the oscillations arise from intracortical circuitry. However, strong oscillations within both the retina and the lateral geniculate nucleus (LGN) have been reported recently. To evaluate the possibility that cortical oscillations arise from peripheral pathways, we have developed two plausible models of single cell oscillatory discharge that specifically exclude intracortical networks. In the first model, cortical oscillatory discharge near 50 Hz in frequency arises from the integration of signals from strongly oscillatory cells within the LGN. The model also predicts the incidence of 50-Hz oscillatory cells within the cortex. Oscillatory discharge around 30 Hz is explained in a second model by the presence of intrinsically oscillatory cells within cortical layer 5. Both models generate spike trains whose power spectra and mean firing rates are in close agreement with experimental observations of simple and complex cells. Considered together, the two models can largely account for the nature and incidence of oscillatory discharge in the cat's visual cortex. The validity of these models is consistent with the possibility that oscillations are generated independently of intracortical interactions. Because these models rely on intrinsic stimulus independent oscillators within the retina and cortex, the results further suggest that oscillatory activity within the cortex is not necessarily associated with the processing of high-order visual information. PMID- 9364730 TI - Contributions of GABAA receptors and GABAC receptors to acetylcholine release and directional selectivity in the rabbit retina. AB - GABA is a major inhibitory neurotransmitter in the mammalian retina and it acts at many different sites via a variety of postsynaptic receptors. These include GABAA receptors and bicuculline-resistant GABAC receptors. The release of acetylcholine (ACh) is inhibited by GABA and strongly potentiated by GABA antagonists. In addition, GABA appears to mediate the null inhibition which is responsible for the mechanism of directional selectivity in certain ganglion cells. We have used these two well-known examples of GABA inhibition to compare three GABA antagonists and assess the contributions of GABAA and GABAC receptors. All three GABA antagonists stimulated ACh release by as much as ten-fold. By this measure, the ED50s for SR-95531, bicuculline, and picrotoxin were 0.8, 7.0, and 14 microM, respectively. Muscimol, a potent GABAA agonist, blocked the effects of SR-95531 and bicuculline, but not picrotoxin. This indicates that SR-95531 and bicuculline are competitive antagonists at the GABAA receptor, while picrotoxin blocks GABAA responses by acting at a different, nonreceptor site such as the chloride channel. In the presence of a saturating dose of SR-95531 to completely block GABAA receptors, picrotoxin caused a further increase in the release of ACh. This indicates that picrotoxin potentiates ACh release by a mechanism in addition to the block of GABAA responses, possibly by also blocking GABAC receptors, which have been associated with bipolar cells. All three GABA antagonists abolished directionally selective responses from ON/OFF directional selective (DS) ganglion cells. In this system, the ED50S for SR-95531, bicuculline, and picrotoxin were 0.7 microM, 8 microM, and 94.6 microM, respectively. The results with SR-95531 and bicuculline indicate that GABAA receptors mediate the inhibition responsible for directional selectivity. The addition of picrotoxin to a high dose of SR-95531 caused no further increase in firing rate. The comparatively high dose required for picrotoxin also suggests that GABAC receptors do not contribute to directional selectivity. This in turn suggests that feedforward GABAA inhibition, as opposed to feedback at bipolar terminals, is responsible for the null inhibition underlying directional selectivity. PMID- 9364733 TI - Callosally projecting neurons in the macaque monkey V1/V2 border are enriched in nonphosphorylated neurofilament protein. AB - Previous immunohistochemical studies combined with retrograde tracing in macaque monkeys have demonstrated that corticocortical projections can be differentiated by their content of neurofilament protein. The present study analyzed the distribution of nonphosphorylated neurofilament protein in callosally projecting neurons located at the V1/V2 border. All of the retrogradely labeled neurons were located in layer III at the V1/V2 border and at an immediately adjacent zone of area V2. A quantitative analysis showed that the vast majority (almost 95%) of these interhemispheric projection neurons contain neurofilament protein immunoreactivity. This observation differs from data obtained in other sets of callosal connections, including homotypical interhemispheric projections in the prefrontal, temporal, and parietal association cortices, that were found to contain uniformly low proportions of neurofilament protein-immunoreactive neurons. Comparably, highly variable proportions of neurofilament protein containing neurons have been reported in intrahemispheric corticocortical pathways, including feedforward and feedback visual connections. These results indicate that neurofilament protein is a prominent neurochemical feature that identifies a particular population of interhemispheric projection neurons at the V1/V2 border and suggest that this biochemical attribute may be critical for the function of this subset of callosal neurons. PMID- 9364734 TI - GABAC receptors on ferret retinal bipolar cells: a diversity of subtypes in mammals? AB - The GABAC receptor subtypes on bipolar cells of rats and cold-blooded vertebrates differ in their pharmacological properties and probably have different molecular compositions. With the exception of the rat, native GABAC receptors in mammals had not been studied. In ferret, whole-cell, voltage-clamp recordings were made from bipolar cells in the retinal slice preparation to determine which subtype of GABAC receptor predominated. Puff-evoked GABA currents in bipolar cells were partially reduced by the GABAA receptor antagonist bicuculline, indicating that both GABAA and GABAC receptors mediated the responses. By contrast, GABA currents of ganglion cells were always completely blocked by bicuculline, indicating that GABAA receptors predominated on these cells. Small-amplitude GABA currents of bipolar cells evoked by short-duration puffs were less sensitive to bicuculline than large-amplitude currents evoked by long-duration puffs. This indicates that GABAC receptors mediated proportionately more of the small-amplitude, puff-evoked responses and GABAA receptors mediated more of the large-amplitude, puff-evoked responses. In bipolar cells, the bicuculline-resistant component of the GABA current was entirely blocked by 3-APMPA (3-aminopropyl-(methyl)phosphonic acid), a GABAC receptor antagonist. Picrotoxin, which is relatively ineffective at rat GABAC receptors, completely blocked GABA currents in ferret bipolar cells, indicating that GABAC receptors on ferret bipolar cells resemble those in lower vertebrates rather than those in the rat retina. These results suggest that there may be a diversity of GABAC receptor subtypes on mammalian bipolar cells. PMID- 9364735 TI - Inhibition of phospholipase C by U-73122 blocks one component of the receptor current in Limulus photoreceptor. AB - In the ventral nerve photoreceptor of Limulus a short, intense flash evokes a receptor current consisting of three components. In contrast to other hypotheses, we suggested previously that only the second component of the current is activated by the phospholipase C pathway, which releases calcium from intracellular stores by inositol trisphosphate. The present paper gives further evidence to our suggestion. It is demonstrated that U-73122, a specific inhibitor for the phospholipase C, selectively blocks the second-component. The first and third components are moderately affected and could still be activated after the complete block of the second one. Results support the idea that the first and third components are activated by pathways operating independently of phospholipase C. PMID- 9364736 TI - Identification of cytochrome P4503A as the major enzyme sub-family responsible for the metabolism of 22,23-dihydro-13-O-[(2-methoxyethoxy)methyl]-avermectin B1 aglycone by rat liver microsomes. AB - 1. Metabolism of 22,23-dihydro-13-O-[(2-methoxyethoxy)methyl]-avermectin B1 aglycone (MEM-H2B1), a new avermectin, by rat liver microsomes has been studied. Metabolites identified were formed by demethylation of the methoxyethoxymethoxy (MEM) side chain, loss of the MEM side chain, partial cleavage and further oxidation of the MEM side chain, and oxidation of the aglycone after cleavage of the MEM side chain. 2. The specific cytochrome P450 isoforms involved in the metabolism of MEM-H2B1 were identified through immunoinhibition studies. Among several antibodies prepared against various cytochrome P450s, only anti-rat P4503A IgG inhibited MEM-H2B1 metabolism by liver microsomes from the untreated rat. Moreover, troleandomycin, a selective suicide inhibitor for enzymes of the cytochrome P4503A family, inhibited the total metabolism by > 80%. These results clearly indicate that cytochrome P4503A is primarily responsible for the metabolism of MEM-H2B1. 3. Secondary metabolism was evident in the metabolism of MEM-H2B1 by dexamethasone and phenobarbital induced liver microsomes, where different isoform(s) of cytochrome P4503A could be involved in these multiple step reactions. PMID- 9364737 TI - N-oxidation of irsogladine by the CYP2C subfamily in the rat, dog, monkey and man. AB - 1. The metabolism of irsogladine (ISG) was studied in hepatic microsomes from the rat, dog, monkey and man, and marked species differences were observed in N oxidation of ISG. The rank order of the activity of the N-oxidation was shown to be man < monkey < dog < rat. 2. Anti-NADPH-P450 reductase antibody inhibited the formation of the N-oxidized metabolite of ISG (ISG-N-oxide) in hepatic microsomes from rats by 74%. Anti-CYP2C11 antibody also inhibited the formation of ISG-N oxide in hepatic microsomes from rat by 73%, whereas anti-CYP2E1, 3A2 and 4A1 antibody did not inhibit N-oxidation. Thus, CYP2C11 in the rat is at least partially responsible for the N-oxidation of ISG in the rat. 3. Anti-CYP2C11 antibody also inhibited the formation of ISG-N-oxide in hepatic microsomes from the dog and monkey by 61 and 46% respectively. Therefore, a isoform(s) similar to CYP2C11 partially contributed to the N-oxidation of ISG in the dog and monkey. In contrast, human CYP2C9, a member of the human CYP2C subfamily, did not catalyse the N-oxidation of ISG. 4. These findings show that the marked species difference in the N-oxidation of ISG is caused by the difference in the catalytic properties of CYP2C among the species examined. PMID- 9364738 TI - Localization, depuration, bioaccumulation and impairment of ion regulation associated with cationic polymer exposure in rainbow trout (Oncorhynchus mykiss). AB - 1. Static exposure of rainbow trout, Oncorhynchus mykiss, to three commercial 14C labelled cationic polymers (EDP, epichlorhydrin-dimethylamine; CYT, polyacrylamide ester; and STK, polyacrylamide amide) resulted in 14C being concentrated only in gill tissue. 2. Depuration studies examining the effect of humic acid (HA) on cationic polymer bound in gill tissue indicate that the binding is reversible with exposure to polymer-free water and polymer-free water with HA for each of the three polymers. 3. Analysis of blood pH, Na+, K+, total NH3 and Cl- after static water exposures to EDP (m.w. 50,000) at 7.5 mg EDP/l revealed a treatment related decrease in blood pH, from 7.1 to 6.6, accompanied by an increase in blood NH3 and evidence of severe impairment of ion regulation. 4. Repeated exposure to the cationic polymers did not result in increases in the 14C concentration in gill tissue suggesting that bioaccumulation of the polymers does not occur. 5. These data suggest that the gill is the site of toxicity for these cationic polymers and that their toxic effects involve gill function and ion regulation rather than systemic actions on internal organs. PMID- 9364739 TI - Rifampin and rifabutin and their metabolism by human liver esterases. AB - 1. The main metabolites of rifampin and rifabutin in man are their respective 25 deacetylated derivatives, but the enzyme(s) responsible for these biotransformations are not known. 2. In experiments with human liver slices and human liver microsomes, the 25 deacetylated derivatives of these drugs were the main metabolites observed. Slices and microsomes metabolized rifabutin 3-6-fold faster than rifampin, in agreement with their relative clearance in patients. Rifabutin partitioned into slices more avidly than rifampin. 3. In microsomal incubations, deacetylation did not require NADPH, but the amount of metabolite at the end of incubation was affected by NADPH. With NADPH the amount of 25 deacetyl rifabutin decreased, whereas the amount of 25 deacetyl rifampin increased slightly. A panel of liver microsomes from seven donors showed a 3-4-fold difference in the formation of 25 deacetyl rifabutin or 25 deacetyl rifampin, with strong correlation between the production of the two metabolites (r2 = 0.94). 4. The production of 25 deacetyl rifabutin and 25 deacetyl rifampin by human liver microsomes was not significantly affected by 1 microM 4 chloromercuricbenzoic acid or bis-(4-nitrophenyl) phosphate, but was completely inhibited by 1 microM paraoxon or 1 microM diisopropylfluorophosphate. These results indicate that in man rifampin and rifabutin are deacetylated to their main metabolites by B-esterases. PMID- 9364740 TI - Identification of the cytochrome P450 isoforms involved in the O-demethylation of 4-nitroanisole in human liver microsomes. AB - 1. 4-Nitroanisole is O-demethylated to 4-nitrophenol by human liver microsomes. Kinetic studies indicate that this metabolic route is mediated by two cytochrome P450 isoforms, one with a K(m) = 2.1 microM and the other with a K(m) = 220 microM. 2. Chemical inhibition and correlation studies in human liver microsomes indicate that the low K(m) enzyme is CYP2A6 and the high K(m) enzyme is CYP2E1 suggesting that44-nitroanisole is not a general cytochrome P450 substrate. 3. Studies using expressed recombinant cytochrome P450s indicated that all the cytochrome P450s investigated metabolized 4-nitroanisole but CYP2A6 and CYP2E1 produced the highest rates. Kinetic studies with these two isoforms produced a K(m) for CYP2A6 of 9 microM and 54 microM for CYP2E1. 4. The involvement of these two isoforms in the O-demethylation of 4-nitroanisole can be rationalized in terms of a hydrogen bond interaction with the nitro group and the active site of CYP2A6 and a hydrophobic interaction with the active site of CYP2E1. PMID- 9364741 TI - Metabolism of a bisphosphonate ester (PNU-91638) in rat. AB - 1. Metabolites of the cyclic bisphosphonate ester, 4-[2,2'-bis-(5,5- dimethyl 1,3,2-dioxaphosphorinan-2-yl)] butanoyl-3-fluoro-benzene (PNU-91638) in bile or urine of the male Sprague-Dawley rat were characterized by mass spectrometry. The chronically bile duct/duodenal-cannulated male rats received a single oral dose of 100 mg/kg [13C] [14C]PNU-91638. Bile and urine samples were analysed for radioactivity and profiled by hplc with radiometric and UV detection. 2. The 0-28 h bile and urine accounted for 46.0 and 19.7% of dose respectively. The structures of radioactive peaks were investigated by ionspray and liquid secondary ion mass spectrometry (LSIMS) and LSIMS/MS analysis. 3. Major metabolites in urine included two regioisomeric phenol glucuronides, a gem methyl hydroxylated metabolite of the bisphosphonate heterocycle, a phenol metabolite, parent drug and a benzylic alcohol metabolite. Additional metabolites in bile included an unstable phenol/glutathione adduct (from a putative epoxide intermediate) with several minor isobaric regioisomers, and a carboxylic acid derived from the gem methyl hydroxylated bisphosphonate ring. 4. The structures proposed have not been confirmed by nmr due to discontinuation of the development of PNU-91638. PMID- 9364742 TI - Absorption, distribution, metabolism and excretion of a new, 14C-labelled oxazolidinone MAO-A inhibitor in rat and dog. AB - 1. After oral administration of 14C-labelled (5R)-3-[2-((1S)-3-cyano-1 hydroxypropyl)benzothiazol-6-yl]-5-metho xymethyl -2-oxazolidinone (E2011) at a dose of 1 mg/kg, the blood level of radioactivity reached a maximum concentration (Cmax) of 0.545 microgram eq./ml after 0.25 h in the rat and of 0.900 microgram eq./ml after 0.5 h in the dog. In dog plasma, Cmax for radioactivity and unchanged E2011 were 0.862 microgram eq./ml and 0.650 microgram/ml respectively with corresponding Tmax (time at Cmax) of 0.75 and 0.25 h. The unchanged drug in dog plasma was below the detection limit (5 ng/ml plasma) after 24 h. 2. The tissue levels of radioactivity were measured at 0.25 (Tmax), 6, 24, and 168 h after administration to the rat and at 0.5 (Tmax), 24, and 168 h in the dog. The radioactivity was distributed in all tissues examined at Tmax in the rat and dog. The radioactivity levels of the cerebral cortex in the rat and dog were 26 and 36% of the plasma level at Tmax. The radioactivity in tissues decreased at almost the same rate as that in plasma. Plasma protein binding of the unchanged drug in the rat in vitro were about 70% in the range of 0.1-10 micrograms/ml, and those in the dog were about 45% in the same concentration range. 3. Cumulative excretion of radioactivity in the rat was 74.5% in urine and 22.5% in faeces after 7 days. In the dog, 55.5 and 36.5% of the radioactivity administered were excreted in urine and faeces respectively after 7 days. The biliary excretion of radioactivity in the cannulated rat was 23.0% within 48 h. 4. In tlc analysis of plasma and tissues of the rat and dog, the radioactivity for the unchanged drug was much higher than metabolites. In tlc analysis of urine, the same metabolites were detected in the rat and dog, and the radioactivity of a metabolite, IM1, was the highest in the both animals. Eight metabolites were detected in the plasma, tissues and excreta of the rat, and four metabolites in the dog. 5. In conclusion, the absorption, distribution, metabolism and excretion of 14C labelled E2011 in the rat and dog have been established, and only minor differences were observed between these species. PMID- 9364743 TI - Identification of the metabolites of a new oxazolidinone MAO-A inhibitor in rat. AB - 1. Six metabolites present in rat urine after the oral administration of E2011 ((5R)-3-[2-((1S)-3-cyano-1-hydroxypropyl)benzothiazol-6-yl]-5-meth oxymethyl-2- oxazolidinone) were isolated with an Amberlite XAD-4 column and hplc, and termed HPM-1, HPM-2, HPM-31, HPM-32, HPM-33 and HPM-4. 2. To determine the correspondence of the findings of the metabolites between tlc (which was used in our previous study) and hplc, the six metabolites were isolated from rat urine after the administration of 14C-labelled E2011 with an Amberlite XAD-4 column and hplc, and then analysed by tlc. HPM-1, HPM-2, HPM-31, HPM-32, HPM-33 and HPM-4 were identified as IM7, IM3, IM4, IM2, IM1 and E2011, respectively. 3. The structures of the metabolites were identified with nmr and mass spectrometry. One of the compounds identified, HPM-4, was the unchanged drug, E2011, and HPM-2 was O-desmethyl-E2011. Another metabolite (HPM-33), the main metabolite in the urine, was identified as (4S)-hydroxy-E2011, and the others were (4S)-hydroxy-O desmethyl-E2011 (HPM-1), 2"-hydroxy-E2011 (HPM-31) and (4R)-hydroxy-E2011 (HPM 32). 4. In conclusion, the main metabolic pathway of E2011 in the rat consisted of O-demethylation and hydroxylation. PMID- 9364744 TI - Formation and pharmacokinetics of the active drug candoxatrilat in mouse, rat, rabbit, dog and man following administration of the prodrug candoxatril. AB - 1. Candoxatrilat, an active neutral endopeptidase inhibitor, was released rapidly from the inactive prodrug candoxatril in vivo in mouse, rat, rabbit, dog and man. 2. Oral doses of [14C]-candoxatril were cleared rapidly, mostly by ester hydrolysis to candoxatrilat, in mouse, dog and man. A complementary intravenous study in man with [14C]-candoxatrilat showed that the active drug was virtually completely renally cleared. Neither candoxatril nor candoxatrilat underwent chiral inversion in man. 3. Systemic availability of candoxatrilat from the oral prodrug was estimated to be 88, 53, 42, 17 and 32% in mouse, rat, rabbit, dog and man respectively. Plasma clearance of candoxatril was too rapid to enable pharmacokinetic parameter calculation in mouse and rabbit; for man, the apparent oral clearance was 57.9 ml/min/kg and the elimination half-life was 0.46 h. 4. For intravenous candoxatrilat, total plasma clearance values were 32, 15, 5.5, 5.8 and 1.9 ml/min/kg for mouse, rat, rabbit, dog and man respectively. Renal clearance values were 8.7, 7.2, 2.9 and 1.7 ml/min/kg for mouse, rat, dog and man and these approximate to the respective glomerular filtration rates. Allometric scaling with respect to bodyweight across the species allowed reasonable prediction of the above two clearance parameters in man. PMID- 9364746 TI - Inducible membranes in yeast: relation to the unfolded-protein-response pathway. AB - Overproduction of an endoplasmic reticulum (ER)-resident membrane protein (cytochrome P450 52A3) and of a secretory protein (invertase) was used to study the regulation of the luminal ER protein Kar2p under conditions that lead to ER proliferation and secretory overload, respectively. In both cases we found (i) a significant increase of Kar2 protein and mRNA levels, (ii) a transcriptional regulation based on the the function of the 22 bp unfolded-protein-response element of the KAR2 promoter and (iii) an essential role of the transmembrane kinase Ire1p for upregulation of KAR2 gene expression. These results show that the same mechanism operates when KAR2 induction is triggered by overproduction of cytochrome P450 or invertase and that this mechanism shares the known features of the unfolded-protein-response pathway. Disruption of the IRE1 gene resulted in a marked decrease of the invertase protein levels produced. In contrast, a functional IRE1 gene was not required to reach high-level production of the integral membrane protein cytochrome P450 52A3, Moreover, IRE1 gene disruption did not prevent P450-induced ER proliferation. We suggest that Ire1p-mediated KAR2 induction is, in the case of cytochrome P450 52A3 overproduction, a process which follows on ER proliferation, thereby monitoring the increase of ER size and adjusting the level of Kar2p accordingly. PMID- 9364745 TI - Characterization and regulation of the genes encoding ribosomal proteins L39 and S7 of the human pathogen Candida albicans. AB - Genes encoding the Candida albicans ribosomal proteins L39 and S7 (RPL39, RPS7) were isolated and sequenced. From RPL39 cDNA a single intron interrupting the fifth codon in the genomic sequence could be deduced. Two homologous RPL39 genes in Saccharomyces cerevisiae contain a single intron in a conserved position. In contrast, C. albicans RPS7 was found to lack an intron, while both S. cerevisiae homologs are interrupted by single introns. The deduced L39 and S7 proteins contained 67% and 83% identical residues compared to the S. cerevisiae homologs. During hyphal induction the RPL39, RPS7 and RPL29 transcript levels increased three- to six-fold relative to ribosomal RNA, while ACT1 and RPS33 control transcripts were not regulated extensively. As suggested by unaltered transcript stabilities during hyphal induction, this regulation occurs on the transcriptional level; a conserved 18 bp palindromic sequence (5' TTAGGGCTATAGCCCTAA-3'), which is present in the promoter regions of the RPL39 and RPS7 genes, may be involved in regulation. PMID- 9364747 TI - Molecular characterization of the glyceraldehyde-3-phosphate dehydrogenase gene of Phaffia rhodozyma. AB - The glyceraldehyde-3-phosphate dehydrogenase (GPD; EC1.2.1.12)-encoding gene (gpd) was isolated from a genomic library of Phaffia rhodozyma CBS 6938. Unlike some other eukaryotic organisms the gpd gene is represented by a single copy in P. rhodozyma. The complete nucleotide sequence of the coding, as well as the flanking non-coding regions was determined. The nucleotide sequence of gpd predicted six introns and a polypeptide chain of 339 amino acids. The codon usage in the gpd gene of P. rhodozyma was highly biased and was significantly different from the codon usage in other yeasts. Phylogenetic analysis of different yeasts and filamentous asco- and basidiomycetes gpd sequences indicated that the gpd gene of P. rhodozyma forms a cluster with the corresponding genes of filamentous basidiomycetes. PMID- 9364748 TI - A phylogenetic analysis of Saccharomyces species by the sequence of 18S-28S rRNA spacer regions. AB - Sequences of two internally transcribed spacer regions between 18S and 28S rRNA genes were determined to assess the phylogenetic relationship in the strains belonging to the genus Saccharomyces. The sequences of S. bayanus and S. pastorianus were quite similar, but not identical. Two phylogenetic trees constructed by the neighbor-joining method showed that all the species examined were distinguished from one another. The Saccharomyces sensu stricto species: S. cerevisiae, S. bayanus, S. paradoxus and S. pastorianus, were closely related and far from the Saccharomyces sensu lato species including S. barnetti, S. castellii, S. dairensis, S. exiguus, S. servazzii, S. spencerorum and S. unisporus, and an outlying species, S. kluyveri. PMID- 9364750 TI - Transcriptional regulation of SUP35 and SUP45 in Saccharomyces cerevisiae. AB - SUP35 and SUP45 encode translational release factors in the yeast Saccharomyces cerevisiae. In addition, Sup35p is related to the cytoplasmically inherited prion like phenotype [PSI+]. The vital cellular role of Sup35p and Sup45p prompted us to study the regulation of transcription of the corresponding genes. Since the [PSI] state of the yeast strain affects the abundance of Sup35p and Sup45p, both [PSI+] and [psi-] variants were included in these analyses. It turned out that SUP35 and SUP45 transcript levels are regulated by nutritional changes and stress in a way strikingly similar to those of ribosomal protein genes. The [PSI] state did not influence the respective transcript levels nor their regulation, although HSP12 (as a monitor of general stress-responsive) gene expression appeared to differ in the two variant strains. The transcription activation sites of SUP35 and SUP45 were mapped using deletion analysis of the respective promoter-reporter fusion genes. The UAS in both cases was found to consist of an Abf1p-site and a T rich element. Also in this respect SUP35 and SUP45 show a notable resemblance with ribosomal protein genes. Evidence was found that SUP35 in addition harbors a potential internal promoter element which became active after progressive 5' deletion removing the first of the three in-frame ATGs. PMID- 9364749 TI - Molecular cloning of chromosome I DNA from Saccharomyces cerevisiae: characterization of the 54 kb right terminal CDC15-FLO1-PHO11 region. AB - Gene density near the ends of Saccharomyces cerevisiae chromosomes is much lower than on the rest of the chromosome. Non-functional gene-fragments are common and a high proportion of the sequences are repeated elsewhere in the genome. This sequence arrangement suggests that the ends of chromosomes play a structural rather than a coding role and may be analogous to the highly repeated heterochromatic DNA of higher organisms. In order to evaluate the function of the ends of S. cerevisiae chromosomes, the rightmost 54-kb of DNA from chromosome I was investigated. The region contains 16 open reading frames (ORFs) and two tRNA genes. Gene-disruption studies indicated that none of these genes are essential for growth on rich or minimal medium, mating or sporulation. In contrast to the central region where 80% of the genes are transcribed when cells are grown on rich medium, only seven ORFs and the two tRNA genes appeared to produce transcripts. Six of the transcribed ORFs were from the centromere-proximal part of the region, leaving the rightmost 35-kb with only a single sequence that is transcribed during vegetative growth. Two genes located 3 and 10-kb from the chromosome I telomere are almost identical to two genes located somewhat further from the chromosome VIII telomere. Surprisingly, the chromosome VIII copies were transcribed while the chromosome I genes were not. These results suggest that the chromosome I genes may be repressed by a natural telomere position effect. The low level of transcription, absence of essential genes as well as the repetitive nature of these sequences are consistent with their having a structural role in chromosome function. PMID- 9364752 TI - Current awareness on yeast. PMID- 9364751 TI - Expression profiles of transcripts from 126 open reading frames in the entire chromosome VI of Saccharomyces cerevisiae by systematic northern analyses. AB - Chromosome VI of Saccharomyces cerevisiae contains 126 open reading frames (ORFs), and the functions of proteins encoded by 80 ORFs are still unknown. In this report, we have systematically examined the expression profiles of all 126 ORFs on chromosome VI under five kinds of growth conditions by quantitative Northern hybridization. A series of Northern analyses and reverse transcription polymerase chain reactions have revealed that more than 64 novel ORFs are transcribed. Two ORFs (YFL059w and YFR011c) are specifically expressed in the presence of galactose. Two ORFs (YFL012w and YFR032c) are specifically transcribed in sporulation. Six ORFs (YFL049w, YFL035c, YFL010c, YFR006w, YFR010w and YFR017c) are abundantly expressed in many growth conditions. PMID- 9364753 TI - No one in my group can be below the group's average: a robust positivity bias in favor of anonymous peers. AB - In Studies 1-8, participants judged an anonymous student as better than the average student, as above the group median, and as better than most other students on a variety of desirable traits. This effect was retained when name and age were removed and student ID number was the only individuating feature, when both the average student and the anonymous student were provide with a first name, and when the order of presentation was reversed. However, the effect was reduced when an enriched version of the average student was provided. In Study 9, an anonymous member of a highly disliked out-group was judged as worse than the out-group average member. These results indicate difficulty in comparing a singular target to a generalized target. A singular-target-focused model of comparative judgments is used to describe how people conduct these assessments. PMID- 9364754 TI - The modern face of prejudice and structural features that moderate the effect of cooperation on affect. AB - Facial muscle activity and self-reports were examined for racial bias in 3 studies. In the first 2 experiments, While participants imagined cooperating with a Black or White partner. Experiment 1 manipulated reward structure in the context of cooperating with a deficient partner. Experiment 2 manipulated partner deficiency and willingness to expend compensatory effort. On both facial EMG and self-report measures, joint rewards produced more negative affect than independent rewards. However, all partners were liked more when they were willing to try to compensate for their deficits. In addition, more liking was reported for Black partners, but EMG activity indicated bias against Blacks. Experiment 3 investigated individual differences in prejudice. Again, a greater preference for Blacks than Whites occurred on self-report measures, but in their facial muscle activity, high-prejudiced participants exhibited bias against Blacks. PMID- 9364755 TI - Butch, femme, or straight acting? Partner preferences of gay men and lesbians. AB - On average, gay men are somewhat feminine and lesbians somewhat masculine, but there is variation within each group. The authors examined the consequences of this variation for gay men's and lesbians' desirability as romantic partners. In 2 studies the authors analyzed personal advertisements. Homosexual people were more likely than heterosexual people to mention traits related to sex typicality and more likely to request sex-typical than sex-atypical partners. In 2 studies the authors assessed partner preferences directly. On average, gay men preferred men who described themselves as masculine rather than feminine, but this preference was weaker among men who rated themselves as relatively feminine. Lesbians preferred women who described themselves as feminine looking but did not discriminate against women calling themselves masculine acting. The authors discuss implications of the results for theories of sexual orientation and the adjustment of sex-atypical homosexual people. PMID- 9364756 TI - Target complicity in the confirmation and disconfirmation of erroneous perceiver expectations: immediate and longer-term implications. AB - The authors explored the role of target self-presentational goals in the expectation confirmation process within the context of simulated employment interviews. As predicted, applicants encouraged to be deferential inadvertently succumbed to their interviewers' expectation; applicants encouraged to be challenging, to advance their own agenda, did not. The challenging-motivated applicants succeeded in disconfirming negative expectations by presenting favorable information about themselves even in the face of negatively constraining interviewer questions; other theoretically relevant behaviors were not supported as mediators. Of added interest, the self-fulfilling prophecies observed for the deference-motivated applicants carried over to a 2nd interview because of changes in applicant self-perceptions following the 1st interview. PMID- 9364757 TI - Psychological theory testing versus psychometric nay-saying: comment on Neuberg et al.'s (1997) critique of the need for closure scale. AB - S. L. Neuberg, T. N. Judice, and S. G. West (1997) faulted our work with the Need for Closure Scale (NFCS) on grounds that the NFCS lacks discriminant validity relative to S. L. Neuberg's and J. T. Newsom's (1993) Personal Need for Structure (PNS) Scale and is multidimensional, which, so they claim, renders the use of its total score inadmissible. By contrast, the present authors show that neither of the above assertions is incompatible with the underlying need for closure theory. Relations between NFCS and the PNS are to be expected, as these were designed to operationalize the very same construct (of need for closure). Furthermore, no unidimensionality of the NFCS has been claimed, and none is required to use its total score for testing various theoretically derived predictions. An instrument's ultimate utility hinges on theoretical considerations and empirical evidence rather than on questionable psychometric dogma unrelated to the substantive matters at hand. PMID- 9364758 TI - Expressive writing moderates the relation between intrusive thoughts and depressive symptoms. AB - The author investigated whether expressive writing enhances emotional adaptation to a stressful event (graduate entrance exams) by reducing event-related intrusive thoughts or by desensitizing people to such thoughts. Participants in the experimental group, who were instructed to write their deepest thoughts and feelings about the exam, exhibited a significant decline in depressive symptoms from 1 month (Time 1) to 3 days (Time 2) before the exam. Participants in the control group, who wrote about a trivial topic, maintained a relatively high level of depressive symptoms over this same period. Expressive writing did not affect the frequency of intrusive thoughts, but it moderated the impact of intrusive thoughts on depressive symptoms. Specifically, intrusive thoughts at Time 1 were positively related to depressive symptoms at Time 2 in the control group and were unrelated to symptoms in the expressive writing group. PMID- 9364759 TI - Pancultural explanations for life satisfaction: adding relationship harmony to self-esteem. AB - The first part of the study confirmed an additive effect of the newly proposed construct of relationship harmony to self-esteem in predicting life satisfaction across student samples from the United States and Hong Kong. As predicted from the dynamics of cultural collectivism, the relative importance of relationship harmony to self-esteem was greater in Hong Kong than in the United States. In the second part of the study, the independent and interdependent self-construals (H. R. Markus & S. Kitayama, 1991) and the 5 factors of personality (P. T. Costa & R. R. McCrae, 1992) were advanced to be the culture-general determinants of life satisfaction, acting through the mediating variables of self-esteem and relationship harmony. Both self-construals and the 5 factors of personality were shown to influence life satisfaction through the mediating agency of self-esteem and relationship harmony in equivalent ways across these 2 cultural groups. PMID- 9364761 TI - Individual differences in the memory representation of emotional episodes: exploring the cognitive processes in repression. AB - Two studies investigated the influence of a repressive coping style on the availability and accessibility of emotion memories. In Study 1 participants rated the presence and intensity of emotions in several scenarios and then estimated the frequency of emotions in the scenarios. Repressors did not process the scenarios more superficially. Repressors indicated the presence of unpleasant emotions in the scenarios less frequently, but not less intensely. The frequency differences accounted for most of the repression effects in the latter frequency judgments. In Study 2 participants judged the frequency of emotions twice a day for 2 weeks and then judged the frequency of emotions for the 1st and 2nd week. Repression effects in the frequency judgments did not increase with longer retention intervals. The results indicate that a repressive coping style influences mainly the experience of emotions but not so much the accessibility of emotion memories. PMID- 9364760 TI - Personality differences predict health-risk behaviors in young adulthood: evidence from a longitudinal study. AB - In a longitudinal study of a birth cohort, the authors identified youth involved in each of 4 different health-risk behaviors at age 21: alcohol dependence, violent crime, unsafe sex, and dangerous driving habits. At age 18, the Multidimensional Personality Questionnaire (MPQ) was used to assess 10 distinct personality traits. At age 3, observational measures were used to classify children into distinct temperament groups. Results showed that a similar constellation of adolescent personality traits, with developmental origins in childhood, is linked to different health-risk behaviors at 21. Associations between the same personality traits and different health-risk behaviors were not an artifact of the same people engaging in different health-risk behaviors; rather, these associations implicated the same personality type in different but related behaviors. In planning campaigns, health professionals may need to design programs that appeal to the unique psychological makeup of persons most at risk for health-risk behaviors. PMID- 9364762 TI - Adult attachment and the suppression of unwanted thoughts. AB - Dismissing-avoidant adults are characterized by expressing relatively low levels of attachment-related distress. However, it is unclear whether this reflects a relative absence of covert distress or an attempt to conceal covert distress. Two experiments were conducted to distinguish between these competing explanations. In Experiment 1, participants were instructed to suppression resulted in a decrease in the accessibility of abandonment-related thoughts for dismissing avoidant adults. Experiment 2 demonstrated that attempts to suppress the attachment system resulted in decreases in physiological arousal for dismissing avoidant adults. These experiments indicate that dismissing-avoidant adults are capable of suppressing the latent activation of their attachment system and are not simply concealing latent distress. The discussion focuses on development, cognitive, and social factors that may promote detachment. PMID- 9364763 TI - Adult attachment in a nationally representative sample. AB - The explosion of adult attachment research in the last decade has been limited by its reliance on college student and distressed samples. Using a large nationally representative sample of American adults, the authors examined the relation of sociodemographics, childhood adversity, parental representations, adult psychopathology, and personality traits to adult attachment in an effort to replicate previous findings and extend the theory. Distribution of adult attachment styles was similar to that in prior studies: 59% secure, 25% avoidant, and 11% anxious. Adult attachment was associated with several sociodemographic variables (e.g., income, age, race) not previously studied. Childhood adversities of an interpersonal nature were strongly related to insecure adult attachment. Various types of adult psychopathologies and personality traits were also strongly related to adult attachment. Implications for adult attachment theory and future research are discussed. PMID- 9364764 TI - Regulatory control and adults' stress-related responses to daily life events. AB - In this study, the authors examined the relations of regulatory control to adults' daily stress-related responses. A physiological index of regulatory control (vagal tone) and daily reports of stress and coping were obtained from 92 college students. The results of the study generally confirmed the prediction that individuals who are high in regulatory control were relatively unlikely to experience high levels of negative emotional arousal in response to stressors, but this relation held only for moderate- to high-intensity stressors. Moreover, under conditions of moderate to high stress, highly regulated individuals were likely to cope constructively with the stressor. Mediational analyses suggested that the relation of regulatory control to constructive coping was partially mediated by negative emotional arousal. The results support the conclusion that individual differences in regulatory control interact with situational factors in influencing the prediction of stress-related responses. PMID- 9364765 TI - The cDNA cloning and molecular evolution of reptile and pigeon lactate dehydrogenase isozymes. AB - The cDNAs encoding lactate dehydrogenase isozymes LDH-A (muscle) and LDH-B (heart) from alligator and turtle and LDH-A, LDH-B, and LDH-C (testis) from pigeon were cloned and sequenced. The evolutionary relationships among vertebrate LDH isozymes were analyzed. Contrary to the traditional belief that the turtle lineage branched off before the divergence between the lizard/alligator and bird lineages, the turtle lineage was found to be clustered with either the alligator lineage or the alligator-bird clade, while the lizard lineage was found to have branched off before the divergence between the alligator/turtle and bird lineages. The pigeon testicular LDH-C isozyme was evidently duplicated from LDH-B (heart), so it is not orthologous to the mammalian testicular LDH-C isozymes. PMID- 9364766 TI - Satellite DNA repeat sequence variation is low in three species of burying beetles in the genus Nicrophorus (Coleoptera: Silphidae). AB - Three satellite DNA families were identified in three species of burying beetles, Nicrophorus orbicollis, N. marginatus, and N. americanus. Southern hybridization and nucleotide sequence analysis of individual randomly cloned repeats shows that these satellite DNA families are highly abundant in the genome, are composed of unique repeats, and are species-specific. The repeats do not have identifiable core elements or substructures that are similar in all three families, and most interspecific sequence similarity is confined to homopolymeric runs of A and T. Satellite DNA from N. marginatus and N. americanus show single-base-pair indels among repeats, but single-nucleotide substitutions characterize most of the repeat variability. Although the repeat units are of similar lengths (342, 350, and 354 bp) and A + T composition (65%, 71%, and 71%, respectively), the average nucleotide divergence among sequenced repeats is very low (0.18%, 1.22%, and 0.71%, respectively). Transition/transversion ratios from the consensus sequence are 0.20, 0.69, and 0.70, respectively. PMID- 9364768 TI - A simple method for estimating the parameter of substitution rate variation among sites. AB - When the rate variation among sites is described by a gamma distribution, an important problem is how to estimate the shape parameter alpha, which is an index of the degree of among-site rate variation. The parsimony-based methods for estimating alpha are simple but biased, i.e., alpha tends to be overestimated. On the other hand, the likelihood-based methods are asymptotically unbiased but take a huge amount of computational time. In this paper, we have developed a new method to solve this problem: we first estimate the expected number of substitutions at each site, which is corrected for multiple hits, and then estimate the parameter alpha. Our method is computationally as fast as the parsimony method, and the estimation accuracy is much higher than that of parsimony and similar to that of the likelihood method. PMID- 9364767 TI - Phylogeography and pleistocene evolution in the North American black bear. AB - To determine the extent of phylogeographic structuring in North American black bear (Ursus americanus) populations, we examined mitochondrial DNA sequences (n = 118) and restriction fragment length polymorphism profiles (n = 258) in individuals from 16 localities. Among the bears examined, 19 lineages falling into two highly divergent clades were identified. The clades differ at 5.0% of nucleotide positions, a distance consistent with an origin 1.8 MYA, and have different but overlapping geographical distributions. Areas of clade cooccurrence show that eastern and western populations are currently mixing, but regional differences in lineage distribution suggest that mixing has begun only recently. The long-term population history of black bears appears to be characterized predominantly by long-term regional isolation followed by recent contact and hybridization. Congruence between the pattern of diversity observed in black bears and patterns of forest refuge formation during the Pleistocene supports earlier speculation that Pleistocene forest fragmentations underlie a common pattern in the phylogeography of North American forest taxa. PMID- 9364769 TI - Dynamic genome organization and gene evolution by positive selection in geminivirus (Geminiviridae). AB - Geminiviruses (Geminiviridae) are a diverse group of plant viruses differing from other known plant viruses in possessing circular, single-stranded DNA. Current classification divides the family into three subgroups, defined in part by genome organization, insect vector, and plant host range. Previous phylogenetic assessments of geminiviruses have used DNA and/or amino acid sequences from the replication-associated and coat protein genes and have relied predominantly on distance analyses. We used amino acid and DNA sequence data from the replication associated and coat protein genes from 22 geminivirus types in distance and parsimony analyses. Although the results of our analyses largely agree with those reported previously, we could not always predict viral relationships based on genome organization, plant host, or insect vector. Loss of correlation of these traits with phylogeny is likely due to improved sampling of geminivirus types. Unrooted parsimony trees suggest multiple independent origins for the monopartite genome. genome organization is therefore a dynamic character. Estimates of nonsynonymous and synonymous nucleotide substitutions for extant and inferred ancestral sequences were used to evaluate hypotheses that the replication associated and coat protein sequences evolve to accommodate plant host and insect vector specificities, respectively. Results suggest that plant host specificity does not solely direct replication-associated protein-evolution but that coat protein sequence does evolve in response to insect vector specificity. Genome organization and, possibly, plant host specificity are not reliable taxonomic characters. PMID- 9364770 TI - A graphical method for detecting recombination in phylogenetic data sets. AB - Current phylogenetic tree reconstruction methods assume that there is a single underlying tree topology for all sites along the sequence. The presence of mosaic sequences due to recombination violates this assumption and will cause phylogenetic methods to give misleading results due to the imposition of a single tree topology on all sites. The detection of mosaic sequences caused by recombination is therefore an important first step in phylogenetic analysis. A graphical method for the detection of recombination, based on the least squares method of phylogenetic estimation, is presented here. This method locates putative recombination breakpoints by moving a window along the sequence. The performance of the method is assessed by simulation and by its application to a real data set. PMID- 9364771 TI - P element domestication: a stationary truncated P element may encode a 66-kDa repressor-like protein in the Drosophila montium species subgroup. AB - Functional P transposable elements can be separated into two distinct classes: mobile elements, which present the canonical structure, with transposase and repressor functions, and immobile P sequences truncated in 5' and 3' by loss of the terminal inverted repeats and exon 3, which retain only the repressor function. This second class was first described in some species of the Drosophila obscura group. Here, we describe a new truncated immobile P sequence cloned from one species of the Drosophila montium subgroup (D. tsacasi) that produces a polyadenylated RNA with a coding capacity for a 66-kDa "repressor-like" protein. The results from a number of different comparisons between P-homologous sequences concerning both coding and noncoding regions strongly suggest that the obscura and montium immobile P sequences as well as the T-type P subfamily derive from the same ancestral mobile P element family. Study of the flanking regions of these immobile P sequences shows that the two immobilizations were produced by two independent events. Our results provide evidence that the molecular domestication of a transposable element family may recur in a species lineage. PMID- 9364772 TI - bilbo, a non-LTR retrotransposon of Drosophila subobscura: a clue to the evolution of LINE-like elements in Drosophila. AB - We used the repetitive character of transposable elements to isolate a non-LTR retrotransposon in Drosophila subobscura. bilbo, as we have called it, has homology to TRIM and LOA elements. Sequence analysis showed a 5' untranslated region (UTR), an open reading frame (ORF) with no RNA-binding domains, a downstream ORF that had structural homology to that of the I factor, and, finally, a 3' UTR which ended in several 5-nt repeats. The results of our phylogenetic and structural analyses shed light on the evolution of Drosophila non-LTR retrotransposons and support the hypothesis that an ancestor of these elements was structurally complex. PMID- 9364773 TI - The mitochondrial control region of Cervidae: evolutionary patterns and phylogenetic content. AB - The mitochondrial control region (CR) sequence, also known as the D-loop, has been determined for six Cervidae (Artiodactyla, Ruminantia): the red and fallow deers (subfamily Cervinae), the brocket deer and two roe deers (subfamily Odocoileinae), and the Chinese water deer (Hydropotinae). These new sequences have been aligned with available cervid and bovid orthologues. Comparative analyses indicate that the 5'-peripheral domain exhibits a 75-bp length polymorphism near sequences associated with the termination of the H-strand replication. The New World Odocoileinae possess the longest cervid CR due to the presence of an additional 47-bp tandem repeat, located in the 3'-peripheral domain, downstream of the initiation site for H-strand replication (OH) and the first conserved sequence block (CSB-1). This insertion represents a duplication spanning the OH to CSB-1 region and constitutes an exclusive synapomorphy for New World Odocoileinae. Phylogenetic analyses of the complete CR support the paraphyly of antlered deers due to the nesting of the antlerless Hydropotes within Odocoileinae. Capreolus is the closest relative of Hydropotes, and the divergence of this Old World Odocoileinae clade may have occurred between 8.7 and 10.4 MYA. The conserved central domain of CR can be aligned across ungulates and indicates the Pecora monophyly, their close association with cetaceans, and the earlier emergence of suiformes. PMID- 9364774 TI - Large, rapidly evolving intergenic spacers in the mitochondrial DNA of the salamander family Ambystomatidae (Amphibia: Caudata). AB - We report the presence, in the mitochondrial DNA (mtDNA) of all of the sexual species of the salamander family Ambystomatidae, of a shared 240-bp intergenic spacer between tRNAThr and tRNAPro. We place the intergenic spacer in context by presenting the sequence of 1,746 bp of mtDNA from Ambystoma tigrinum tigrinum, describe the nucleotide composition of the intergenic spacer in all of the species of Ambystomatidae, and compare it to other coding and noncoding regions of Ambystoma and several other vertebrate mtDNAs. The nucleotide substitution rate of the intergenic spacer is approximately three times faster than the substitution rate of the control region, as shown by comparisons among six Ambystoma macrodactylum sequences and eight members of the Ambystoma tigrinum complex. We also found additional inserts within the intergenic spacers of five species that varied from 87-444 bp in length. The presence of the intergenic spacer in all sexual species of Ambystomatidae suggests that it arose at least 20 MYA and has been a stable component of the ambystomatid mtDNA ever since. As such, it represents one of the few examples of a large and persistent intergenic spacer in the mtDNA of any vertebrate clade. PMID- 9364775 TI - RFLP markers show genetic recombination in Botryotinia fuckeliana (Botrytis cinerea) and transposable elements reveal two sympatric species. AB - Molecular markers revealed that Botryotinia fuckeliana (the teleomorph of Botrytis cinerea), a haploid, filamentous, heterothallic ascomycete, contained a large amount of intrapopulation genetic variation. The markers were used to determine the mode of reproduction and the population structure of this fungus. We did not detect any differentiation between isolates from different organs, collection dates, varieties of grape, or locations in the Champagne region of France, but two unexpected sympatric populations were identified. One group of isolates (transposa) contained the transposable elements Boty and Flipper; the other (vacuma) did not. These groups differed from one another for all the other markers. RFLP markers showed that there was genetic recombination in both groups of isolates. We conclude that there are two sympatric populations of B. fuckeliana in Champagne. One species (transposa) seems to be local and well adapted, while the other one (vacuma) is presumably a heterogeneous migrant population. PMID- 9364776 TI - Natural products derived from unusual variants of the shikimate pathway. PMID- 9364777 TI - Secondary metabolites from marine microorganisms: bacteria, protozoa, algae and fungi. Achievements and prospects. PMID- 9364778 TI - Coumarins. PMID- 9364779 TI - Biosynthesis of polyketides. PMID- 9364780 TI - Functional segregation and temporal hierarchy of the visual perceptive systems. AB - In extending our previous work, we addressed the question of whether different visual attributes are perceived separately when they belong to different objects, rather than the same one. Using our earlier psychophysical method, but separating the attributes to be paired in two different halves of the screen, we found that human subjects misbind the colour and the direction of motion, or the colour and the orientation of lines, because colour, form, and motion are perceived separately and at different times. The results therefore show that there is a perceptual temporal hierarchy in vision. PMID- 9364781 TI - Temporal hierarchy of the visual perceptive systems in the Mondrian world. AB - Our earlier psychophysical work has shown that colour and motion are not perceived at the same time, with colour leading motion by about 50-100 ms. In pursuing this work, we thought it would be interesting to use a more complex colour stimulus, one in which the wavelength composition of the light reflected or emitted from surfaces changes continually, without entailing a change in the perceived colour (colour constancy). We therefore used a Mondrian figure--an abstract multi-coloured scene with no recognizable objects--against which squares (either red or green) moved up and down, changing colour from red to green in various phase differences with the change in direction of motion. The red and green squares changed continually in their spectral characteristics, as did every other patch on the Mondrian. The results showed that colour is still perceived before motion, by about 80 ms. PMID- 9364782 TI - The direction of retinal motion facilitates binocular stereopsis. AB - Visual information from binocular disparity and from relative motion provide information about three-dimensional structure and layout of the world. Although the mechanisms that process these cues have typically been studied independently, there is now a substantial body of evidence that suggests that they interact in the visual pathway. This paper investigates one advantage of such an interaction: whether retinal motion can be used as a matching constraint in the binocular correspondence process. Stimuli that contained identical disparity and motion signals but which differed in their fine-scale correlation were created to establish whether the direction, or the speed, of motion could enhance performance in a psychophysical task in which binocular matching is a limiting factor. The results of these experiments provide clear evidence that different directions of motion, but not different speeds, are processed separately in stereopsis. The results fit well with properties of neurons early in the cortical visual pathway which are thought to be involved in determining local matches between features in the two eyes' images. PMID- 9364783 TI - Are faces of different species perceived categorically by human observers? AB - What are the species boundaries of face processing? Using a face-feature morphing algorithm, image series intermediate between human, monkey (macaque), and bovine faces were constructed. Forced-choice judgement of these images showed sharply bounded categories for upright face images of each species. These predicted the perceptual discrimination boundaries for upright monkey-cow and cow-human images, but not human-monkey images. Species categories were also well-judged for inverted face images, but these did not give sharpened discrimination (categorical perception) at the category boundaries. While categorical species judgements are made reliably, only the distinction between primate faces and cow faces appears to be categorically perceived, and only in upright faces. One inference is that humans may judge monkey faces in terms of human characteristics, albeit distinctive ones. PMID- 9364784 TI - Vaccination and the population structure of antigenically diverse pathogens that exchange genetic material. AB - Populations of antigenically diverse pathogens undergoing genetic exchange may be categorized into strains on the basis of a set of principal protective antigens. The extent to which polyvalent vaccines based on these protective antigens can alter the population structure of the pathogen is determined by the degree of cross-protection between strains. In the case where there is no cross-protection, vaccinating against a particular strain will have no effect on the others. As cross-protection increases, the strains containing the antigenic variants included in the vaccine will be diminished in prevalence, and those that do not will increase in prevalence. The rise in prevalence of the latter will become more and more exaggerated as cross-protection increases. However, beyond a critical level of cross-protection, in the absence of vaccination, the steady state of the system is asymmetric in that a certain subset of strains (with non overlapping repertoires of antigenic variants) will dominate over the others in terms of prevalence. Under these circumstances, a vaccine consisting of the most immunogenic combinations of antigenic variants can cause a dramatic increase in frequency of a subset of rare strains. PMID- 9364785 TI - A genetic interpretation of heightened risk of BSE in offspring of affected dams. AB - An analysis is presented of the results of a cohort study designed to test whether or not the aetiological agent of bovine spongiform encephalopathy (BSE) in cattle can be transmitted maternally (vertically) from dam offspring. Various genetic models are fitted to the data under the assumption that the results could be explained entirely by genetic predisposition to disease (as opposed to maternal transmission) given exposure of offspring of diseased and unaffected dams to contaminated cattle feed. The analyses suggest that the results could be explained by the hypothesis of genetic predisposition, provided a large difference exists in the susceptibility of resistant and susceptible hosts, and explore the range of genotypic parameters and frequencies consistent with the limited currently available data. The results presented are broadly robust, even under the scenario that a portion of the observed maternally enhanced risk of BSE is due to a low level of maternal transmission in late incubation stage dams. PMID- 9364786 TI - The effect of cowpox virus infection on fecundity in bank voles and wood mice. AB - Although epidemic infectious diseases are a recognized cause of changes in host population dynamics, there is little direct evidence for the effect of endemic infections on populations. Cowpox virus is an orthopoxvirus which is endemic in bank voles (Clethrionomys glareolus), wood mice (Apodemus sylvaticus) and field voles (Microtus agrestis) in Great Britain. It does not cause obvious signs of disease nor does it affect survival, but in this study we demonstrate experimentally that it can reduce the fecundity of bank voles and wood mice by increasing the time to first litter by 20-30 days. The pathogenic mechanisms causing this effect are at present not known, but this finding suggests that natural subclinical infection could have a considerable effect on the dynamics of wild populations. PMID- 9364787 TI - Body odour preferences in men and women: do they aim for specific MHC combinations or simply heterozygosity? AB - The major histocompatibility complex (MHC) is an immunologically important group of genes that appears to be under natural as well as sexual selection. Several hypotheses suggest that certain MHC-allele combinations (usually heterozygous ones) are superior under selective pressure by pathogens. This could influence mate choice in a way that preferences function to create MHC-heterozygous offspring, or that they function to create specific allele combinations that are beneficial under the current environmental conditions through their complementary or epistatic effects. To test these hypotheses, we asked 121 men and women to score the odours of six T-shirts, worn by two women and four men. Their scorings of pleasantness correlated negatively with the degree of MHC similarity between smeller and T-shirt-wearer in men and women who were not using the contraceptive pill (but not in Pill-users). Depending on the T-shirt-wearer, the amount of variance in the scorings of odour pleasantness that was explained by the degree of MHC similarity (r2) varied between nearly 0 and 23%. There was no apparent effect of gender in this correlation: the highest r2 was actually reached with one of the male odours sniffed by male smellers. Men and women who were reminded of their own mate/ex-mate when sniffing a T-shirt had significantly fewer MHC alleles in common with this T-shirt-wearer than expected by chance. This suggests that the MHC or linked genes influence human mate choice. We found no significant effect when we tested for an influence of the MHC on odour preferences after the degree of similarity between T-shirt-wearer and smeller was statistically controlled for. This suggests that in our study populations the MHC influences body odour preferences mainly, if not exclusively, by the degree of similarity or dissimilarity. The observed preferences would increase heterozygosity in the progeny. They do not seem to aim for more specific MHC combinations. PMID- 9364789 TI - No evidence of sperm selection by female common shrews. AB - There is currently much interest in the suggestion that females are capable of post-copulatory (or cryptic) choice for male genetic compatibility. Here, I investigate this idea using data from mixed-paternity litters of the common shrew (Sorex araneus). Females of this species are highly promiscuous and, in natural populations, regularly incur costs of inbreeding by mating with close relatives. Selection should therefore favour female ability for sperm selection on the basis of male relatedness. No evidence was found in support of this idea. Relative number of offspring sired within mixed paternity litters was not significantly correlated with genetic similarity of males to the female mated. Relative fertilization success was, however, significantly related to male epididymal sperm counts. I conclude that most variation in relative fertilization success of male common shrews can be explained in terms of sperm competition, and that females of this species may not be capable of sperm selection. PMID- 9364788 TI - The bloodstream differentiation-division of Trypanosoma brucei studied using mitochondrial markers. AB - In the bloodstream of its mammalian host, the African trypanosome Trypanosoma brucei undergoes a life cycle stage differentiation from a long, slender form to a short, stumpy form. This involves three known major events: exit from a proliferative cell cycle, morphological change and mitochondrial biogenesis. Previously, models have been proposed accounting for these events (Matthews & Gull 1994a). Refinement of, and discrimination between, these models has been hindered by a lack of stage-regulated antigens useful as markers at the single cell level. We have now evaluated a variety of cytological markers and applied them to investigate the coordination of phenotypic differentiation and cell cycle arrest. Our studies have focused on the differential expression of the mitochondrial enzyme dihydrolipoamide dehydrogenase relative to the differentiation-division of bloodstream trypanosomes. The results implicate a temporal order of events: commitment, division, phenotypic differentiation. PMID- 9364790 TI - Density-related changes in sexual selection in red deer. AB - In sexually dimorphic mammals, high population density is commonly associated with increased mortality of males relative to females and with female-biased adult sex ratios. This paper investigates the consequences of these changes on the distribution of male breeding success, the intensity of competition for females and the opportunity for sexual selection. After the red deer (Cervus elaphus L.) population of the North Block of Rum (Inner Hebrides) was released from culling, female numbers rose and male numbers declined, leading to an adult sex ratio of around one male to two females. This change was the result of increased mortality of males relative to females during the first two years of life; of increased emigration rates by young males; and of reduced immigration by males from outside the study area. The increasing bias in the adult sex ratio affected the timing of breeding as well as the distribution of mating success in males. As the adult sex ratio became increasingly biased towards females, the degree of skew in mating success (calculated across all harem-holders) increased, but mature males defended harems for shorter periods and a higher proportion of males held harems. In addition, a higher proportion of calves were fathered by immigrant males and the proportion fathered by males born in the study area declined. These results support the contention that, where high population density is associated with a female-biased adult sex ratio, competition for mates is likely to decline. PMID- 9364791 TI - Resolution of the phylogenetic position of the Congo peafowl, Afropavo congensis: a biogeographic and evolutionary enigma. AB - Afropavo congensis, the Congo peafowl, has long fascinated ornithologists because of its uncertain phylogenetic position and unusual geographic distribution. While some researchers have placed Afropavo as a sister taxon to the true peafowl, Pavo species, others have suggested relationships with the guineafowl or an Old World partridge, Francolinus. These divergent opinions are due, at least in part, to (i) the unique morphological characteristics, lack of elaborate ornamentation, and monogamous mating system in Afropavo which differentiates it from Pavo; and (ii) the restricted distribution of Afropavo in Zaire, which is far removed from the Asian distribution of all other pheasant species. We obtained complete cytochrome b and partial D-loop sequences of Afropavo and compared them to Pavo, guineafowl, Francolinus and other galliform taxa. Our results strongly support a close relationship between Afropavo and Pavo, and we were able to reject alternative phylogenetic hypotheses. Molecular clock estimates of the divergence time place the separation of Afropavo and Pavo in the late Miocene. We also discuss other relatives of Afropavo and Pavo and use this information to propose hypotheses regarding the evolution of ornamentation and sexual dimorphism within this group of pheasants. PMID- 9364792 TI - Minimizing cationization effects in the analysis of complex mixtures of oligosaccharides. AB - We outline simple methodology for the rapid and selective analysis of 2 aminoacridone (2-AMAC) derivatised oligosaccharides by matrix-assisted laser desorption/ionization mass spectrometry. This involves the addition of small amounts of lithium chloride to the matrix before evaporation of solvent and crystallization. Signals mainly attributed to proton, sodium and potassium adducts are suppressed to a great extent, and a single signal due to (M + Li)+ is observed. This technique is rapid and is most useful for the direct analysis of complex glycan mixtures, after derivatization with 2-aminoacridone and without separation of the individual components. PMID- 9364793 TI - A new technique for decomposition of selected ions in molecule ion reactor coupled with ortho-time-of-flight mass spectrometry. AB - A molecule ion reactor (MIR), i.e. a gas filled radio-frequency only quadrupole with a longitudinal electrical field (RFQLEF), is used as an atmospheric pressure ionization interface for an orthogonal time-of-flight mass spectrometer (O TOFMS). A new phenomenon of selective ion 'heating' in a MIR near Mathieu's instability threshold was found and confirmed by computer simulation. The 'heating' in collisions with buffer gas molecules leads to ion decomposition. In the case of multicharged ions, fragments with an m/z value higher than that of the parent ion have a stable motion and can be analysed by an O-TOFMS. Fragmentation of bradykinin and beta-endorphin molecular ions having a selected charge state is demonstrated. The spectra show clear 'ladder' structure. The phenomenon may be used as an alternative to tandem mass spectrometry (MS/MS) for molecule structure analysis. PMID- 9364794 TI - Detection of single-nucleotide mutations including substitutions and deletions by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. AB - Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was applied to the detection of mutations involving single nucleotides. For detection of a single-nucleotide deletion, a normally 44 bp region of the L1CAM gene was amplified in a 50 microL solution, and measurement was carried out on the DNA sample after phenol extraction and ethanol precipitation. A molecular mass decrease of 300 Da corresponding to a single nucleotide was identified in the amplified product of patient DNA. For detection of a substitution, an amplified product from a 50 bp region of the human beta globin gene was cleaved with restriction endonucleases HaeIII and Bsp12861. Measurement of a mixture of digested fragments, or restriction fragment mass mapping, clearly identified a heterozygous G/C mutation in the molecular ion signals for both sense and antisense single-stranded DNAs. The results indicate that MALTI-TOFMS is feasible for genetic diagnosis of point mutations. PMID- 9364795 TI - Quantification of heterocyclic amine carcinogens in cooked meats using isotope dilution liquid chromatography/atmospheric pressure chemical ionization tandem mass spectrometry. AB - Heterocyclic aromatic amines (HAAs) are formed in cooked meats through pyrolysis reactions of different amino acids in the presence or absence of creatine/creatinine and sugars. HAAs are mutagens, colon/mammary gland carcinogens in rodents, and are suspected in the etiology of human cancers. In this study, cooked meats containing incurred HAAs as well as control (microwave) meat, were spiked with four labeled HAA internal standards (MeIQx, IQ, AAC and PhIP) and extracted using a liquid/liquid cleanup procedure. Isotope dilution measurements were made using on-line liquid chromatography atmosphere pressure chemical ionization tandem mass spectrometry with multiple reaction monitoring to provide the sensitivity and specificity needed for trace analysis in these complex matrices. The procedure was validated using control meat spiked with the four native HAAs at 0-50 ppb. The levels of HAAs found in cooked meats ranged from non-detectable (limit of detection 0.1-1.0 ppb) in microwave-cooked hamburger to 226 ppb PhIP and 104 ppb AAC in well-done grilled chicken. This methodology has the potential to provide accurate data on the consumption of HAAs in the diet for use in human cancer risk assessment. PMID- 9364796 TI - Analysis of radiation induced nucleobase-peptide crosslinks by electrospray ionization mass spectrometry. AB - Upon exposure to ionizing radiation, DNA undergoes a variety of modifications including the production of a covalent bond between the nucleobase thymine and the amino acid tyrosine. These crosslinked lesions, produced in cells exposed to ionizing radiation, if unrepaired are thought to result in cell death. We have used electrospray ionization mass spectrometry (ESI-MS) to study a model system consisting of the peptide angiotensin, a 10 amino acid peptide containing only one tyrosine residue, irradiated in the presence of the nucleobase thymine. The presence of the covalently crosslinked species has been determined by ESI-MS, by the appearance of additional species in the irradiated samples which correspond to the adduction of thymine as well as a hydrated species containing thymine and water (5-hydroxy-6-hydrothymine). The formation of 5-hydroxy-6-hydrothymine adduct is reversible and the relative abundance of the thymine and 5-hydroxy-6 hydrothymine adducts is dependent on the pH of the spray solution. High resolution experiments using Fourier transform ion cyclotron resonance mass spectrometry confirms the presence of the thymine and hydrated thymine adducts. The high resolution nature of these experiments also allows the detection of a 5,6-dihydrothymine adduct. PMID- 9364797 TI - Fragmentation of complex carbohydrates following ionization by matrix-assisted laser desorption with an instrument fitted with time-lag focusing. AB - Matrix-assisted laser desorption/ionization time-of-flight spectra of carbohydrates recorded with an instrument using time-lag focusing (delayed extraction) were found to exhibit fragment ions, whereas, in the non time-lag focusing mode, fragment ions were not observed. Fragment ions consisted both of glycosidic and cross-ring cleavage products whose absolute, but not relative abundance increased with the delay time and indicated that they were formed within the ion source. Only the glycosidic cleavage ions were present in post source decay spectra and their abundance was inversely correlated with the delay time. The results indicated that the cross-ring cleavages were predominately the products of fast reactions whereas the glycosidic cleavages occurred over a longer time frame. PMID- 9364799 TI - Rapid simultaneous analysis of prostaglandin E2, 12-hydroxyeicosatetraenoic acid and arachidonic acid using high performance liquid chromatography/electrospray ionization mass spectrometry. AB - Arachidonic acid (AA) can be metabolized to a variety of lipid mediators including prostaglandins (PGE), and hydroxyeicosatetraenoic acids (HETE) by cyclooxygenase, lipoxygenase and cytochrome P450-dependent monooxygenase enzymatic pathways. Traditional experimental procedures to quantify these lipid mediators require purification, often by high performance liquid chromatography (HPLC), prior to derivatization for gas chromatography/mass spectrometry (GC/MS) analysis. This paper describes a rapid and simple technique for the simultaneous quantitative analysis of PGE2, 12-HETE, and AA by HPLC/electrospray ionization mass spectrometry on cultured human dermal fibroblast supernatants. Extension of the method to analyse 5-HETE and 15-HETE was investigated. The advantages of this method include minimal sample preparation and elimination of the problem associated with thermal stability for GC/MS analysis. A detection limit of 20pg on column for PGE2 and 5pg on column for 12-HETE and AA was determined. PMID- 9364798 TI - Use of a non-porous polyurethane membrane as a sample support for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of peptides and proteins. AB - Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) of proteins and peptides was performed on samples deposited onto non-porous ether-type polyurethane (PU) membranes. Spectra obtained using PU membranes showed that mass resolution and accuracy were equivalent to values observed using a metal target, and superior to those obtained using poly(vinylidene difluoride) (PVDF) membranes. A small apparent increase in the mass of proteins and also loss of resolution were observed at very high laser irradiance due to charging, but were not observed under normal conditions. Analysis of NaCl-doped standards demonstrated that PU membranes yielded better results than a metallic target for salt-containing solutions. Relatively strong hydrophobic interactions between the proteins and peptides and the PU membrane allowed the incorporation of a washing step. This step allowed for the removal of salts and buffer components and thus provided an increase in resolution and mass accuracy. Digestion of citrate synthase (a protein of molecular weight 47,886) with trypsin was performed directly on the surface of the membrane for variable periods of time, and characteristic peptide fragments were observed by MALDI TOFMS. Delayed extraction was used to increase the resolution and to permit more accurate mass assignments for those fragments. The use of PU membranes for MALDI TOFMS analysis of proteins with higher molecular weights is also demonstrated. PMID- 9364800 TI - Lactation-associated and prolactin-responsive changes in protein synthesis in mouse mammary cells. AB - Lactational function in the mammary epithelial cell is subject to complex regulation, most probably involving multiple extracellular and intracellular proteins that act at any of a number of levels. Although some of these proteins have been identified it is likely that additional controllers of lactation exist, but have yet to be discovered. In an effort to identify such proteins, a search was made for non-milk lactation-associated or prolactin-responsive proteins in primary mouse mammary epithelial cells and the mouse mammary epithelial cell line, COMMA-D using two-dimensional electrophoresis on large-format gels. These analyses revealed 12 proteins whose rate of synthesis was dependent on lactation state or on response to prolactin. Two of these (p77 and p63) were lactation associated in primary cells and prolactin-responsive in COMMA-D cells. These two proteins were identified by amino acid sequencing as glucose-regulated protein 78 (GRP78) and protein disulphide isomerase (PDI). The localization of these proteins in the endoplasmic reticulum and their presence in other secretory cell types and tissues suggests that they have a function in the processing or secretion of milk proteins. PMID- 9364801 TI - The development and utility of a defined muscle and fat co-culture system. AB - The utility of co-culture systems in defining the interactions between two different cell types has been well documented in the literature but is a relatively new tool for use in the study of cells derived from normal muscle tissue from meat animals. The majority of myonuclei in postnatal skeletal muscle cells (myofibers) result from satellite cell proliferation, differentiation and fusion with existing myofibers. As such, satellite cell culture systems that mimic postnatal myofibers have great potential for delineating the process of growth and repair of muscle mass. Other ways to simulate the environment of postnatal myofibers might include the development of co-culture systems using satellite cells, or satellite cell-derived myotubes, and other mesodermal cells commonly found associated with muscle tissue in vivo. This brief review describes our initial efforts to develop a defined satellite cell and preadipocyte co culture system. We provide useful information about defined media requirements and requirements for proper cell orientation and growth on two different growth planes. We present summary data to suggest that differences were found between members of the insulin-like growth factor (IGF) and IGF-binding protein (IGFBP) families of polypeptides, when conditioned media samples were analyzed from co cultures composed of 3T3-L1 preadipocytes and satellite cells (with different propensities to undergo morphological fusion to form multinucleated myotubes). We also provide information about potential problems to avoid when initiating and conducting co-culture experiments. Such a co-culture system has application in the study of human obesity and also in the regulation of fat deposition in meat animals. PMID- 9364802 TI - Relationship between expression of integrins and granulosa cell apoptosis in ovarian follicles of the marmoset (Callithrix jacchus). AB - DNA fragmentation (apoptosis) was studied during the follicular, periovulatory and luteal phase in the marmoset monkey ovary by means of terminal transferase mediated in situ nick end labeling, and correlated with immunohistochemical localization of integrins (beta 1, alpha 2 and alpha 6 subunits). For this purpose a double-labeling technique was developed. During all phases, apoptosis of granulosa cells was exclusively restricted to tertiary follicles displaying advanced stages of atresia (as morphologically determined). During early stages of atresia in tertiary follicles, indicated by widened intercellular spaces, no apoptosis was seen. Staining intensities for integrins beta 1 and alpha 6 were strong in intact primordial/primary, secondary and tertiary follicles. Integrin expression of granulosa cells was weak in atretic tertiary follicles but not in atretic primary or secondary follicles. Double labeling revealed that DNA fragmentation was solely found in granulosa cells of tertiary follicles displaying faint or absent staining for both integrin subunits. During the periovulatory and the luteal phase, granulosa cells of atretic tertiary follicles bordering on the basal membrane, which were referred to as luteinizing cells, expressed the beta 1 subunit as well as the alpha 2-integrin subunit whereas granulosa cells neighboring to the antrum were apoptotic and negative for integrin immunoreactivity. In summary, early atresia of tertiary follicles is first characterized by morphological alterations as wide intercellular gaps, without any signs of granulosa cell apoptosis. Advanced stages of atresia, in tertiary follicles however, are accompanied by apoptosis of granulosa cells and a faint or absent staining for integrin subunits beta 1 and alpha 6. According to recent in vitro findings, our results point to a possible relation between granulosa cell apoptosis of tertiary follicles and integrin expression in ovarian marmoset follicles. PMID- 9364803 TI - Shrinkage and distortion of the rabbit corneal endothelial cell mosaic caused by a high osmolality glutaraldehyde-formaldehyde fixative compared to glutaraldehyde. AB - The purpose of this study was to quantitatively compare cell dimensions and cell layer organization of the corneal endothelium after chemical fixation. Rabbit corneas (9-10 weeks of age) were prepared immediately postmortem for transmission electron microscopy (TEM) and scanning electron microscopy (SEM) using either a widely used high osmolality fixative (glutaraldehyde-formaldehyde, after Karnovsky; 1% formaldehyde, 2.5% glutaraldehyde, 0.1 M cacodylate, pH 7.6, 850 mOsm/kg) or a glutaraldehyde fixative (2% glutaraldehyde in 80 mM cacodylate, pH 7.4, 330 mOsm/kg). With the glutaraldehyde-formaldehyde fixative, TEM revealed gross shrinkage (up to 40%) and distortion of the cytoplasm and organelles, while the regions of the cell-cell junctions were not attenuated but included dilated extracellular space. With the glutaraldehyde fixative, TEM also revealed shrinkage but the cytoplasm was less compact than with the high osmolality fixative. The overall cell shrinkage and relative accentuation of the cell-cell borders was confirmed by SEM, which also revealed that the 11 to 20% area shrinkage was also related to the number of cell sides. PMID- 9364804 TI - An immunocytochemical and ultrastructural study of the larval anterior intestine of the frog Rana temporaria, with especial reference to endocrine cells. AB - Endocrine cells of the larval intestine of Rana temporaria tadpoles have been identified by argyrophilic, immunocytochemical and electron-microscopical techniques. Scarce endocrine cells have been found in both the short non absorptive zone immediately following the stomach, and in the rest of the anterior intestine. Endocrine cells are frequently seen to extend a cytoplasmic process towards the lumen. Immunoreactivity for serotonin, somatostatin, bombesin and cholecystokinin-8 has been detected. According to the ultrastructural traits of the endocrine granules, three larval intestinal endocrine populations have been differentiated. PMID- 9364805 TI - Expression of tubulin isoforms during the differentiation of mammalian spermatozoa. AB - Using the GT 335 mAb we have previously demonstrated a differential expression of glutamylated tubulin isoforms during spermatogenesis and in spermatooza of the mouse and human. Moreover, the proximodistal decrease of the immunolabeling and its predominance in doublets 1-5-6, corresponding to the plane of the flagellar wave, suggested that the glutamylated tubulin could be involved in a functional heterogeneity of microtubules in peripheral doublets of the sperm flagellum. In order to characterize further the importance of glutamylated tubulin in the sperm model, we analyzed tubulin isoforms by immunoblotting and quantitative immunogold, using antibodies to the C-terminal domain of both subunits including non-glutamylated and glutamylated epitopes. The unique differential immunolabeling of the glutamylated tubulin was confirmed with three mAbs 406-3, 392-2 and B3, in addition to GT 335. This differential labeling was interpreted as a differential accessibility of tubulin epitopes since it was greatly reduced in human spermatozoa lacking dynein arms and after motility inhibition of normal spermatozoa by azide pretreatment. We suggest that the glutamylated tubulin interacts with other axonemal and/or periaxonemal proteins which could be involved in flagellar beating and its regulation. PMID- 9364806 TI - An ageing-associated decline in force production after repetitive contractions by rat skinned skeletal muscle fibres. AB - Chemically skinned muscle fibre segments were prepared from the extensor digitorum longus (EDL) and soleus muscles of young (5-6 months) and old (24-31 months) male Wistar rats. Muscle fibres were activated repetitively with a buffered calcium solution a total of 50 times, and the force resulting from each activation recorded. Both EDL and soleus fibres showed a substantial decline in maximum force over the series of 50 contractions. The decline in maximum force was significantly higher in old EDL and soleus fibres than in their young counterparts, indicating a difference between the contractile apparatus of skeletal muscle from young and old animals. Normalized tension, defined as force per muscle fibre cross-sectional area, was significantly lower in fibres from the old animals than from the young, giving further evidence of the existence of changes to the contractile apparatus with ageing. PMID- 9364807 TI - The effects of colony-stimulating factor-1 on the number and ultrastructure of osteoclasts in toothless (tl) rats and osteopetrotic (op) mice. AB - The role of colony-stimulating factor-1 (CSF-1 or M-CSF) in osteoclast development is illustrated by observations that administration of exogenous CSF-1 increases osteoclast number and improves the skeletal sclerosis of two osteopetrotic mutations, toothless (tl) in the rat and osteopetrotic (op) in the mouse. We examined the effects of CSF-1 treatment on the number and ultrastructure of osteoclasts in the tibial metaphysis of normal and mutant animals of both stocks to understand the similarities and differences between these two mutations. Osteoclasts from normal animals of both stocks were abundant and possessed the ultrastructural features of active cells. These included apical areas in contact with mineralized surfaces with tightly apposed clear zones, extensive ruffled borders, and a vacuolated cytoplasm with numerous mitochondria. In toothless rats osteoclasts were difficult to locate and those present had poorly defined ruffled borders, fewer cytoplasmic vacuoles, and a basal membrane with both smooth and ruffled areas. Large lipid accumulations were often found near tl osteoclasts. Osteoclasts in op mice were difficult to find, but more numerous than in tl rats. Unlike tl osteoclasts, those of op mice possessed very well developed ruffled borders, small clear zones, and large electron-dense cytoplasmic inclusions. These cells also had unusual basal membranes with both smooth and ruffled regions. CSF-1 treatment increased the number of osteoclasts in both mutant stocks, normalizing the numbers in op mice, but not tl rats. CSF-1 injections caused dramatic changes in the morphology of tl osteoclasts, including increased incidence and size of ruffled borders and cytoplasmic vacuolization. The growth factor had little effect on ruffled borders or clear zones in op mice. Interestingly, mutant osteoclasts of both stocks exhibited a ruffled basal membrane in response to CSF-1 treatment. This increase in membrane ruffling may reflect the ability of CSF-1 to promote rapid formation of osteoclasts from mononuclear precursors in a more permissive microenvironment. Our data indicate that CSF-1 is not required for the development of at least some osteoclasts. The differences in response to CSF-1 treatment which we report lead us to speculate that additional factors may be involved in osteoclastogenesis. PMID- 9364808 TI - Effect of varying noise stress duration on rat adrenal gland: an ultrastructural study. AB - The present study was performed to examine the effect of varying duration of noise exposure on rat adrenal gland. Animals were exposed to noise for 1, 6 and 12 h continuously and the sections obtained from exposed rats were compared to those from corresponding controls. No significant ultrastructural changes were found in the zona glomerulosa, while mitochondria of the zona fasciculata showed matrix dilution and cristolysis after 1 and 12 h of noise stress. At all exposure times examined, the zona reticularis exhibited areas of diluted cytoplasm, disarranged endoplasmic reticulum, membrane vestigia and some altered mitochondria. Diluted cytoplasmic areas appeared in noradrenaline- and adrenaline storing cells after 6 and 12 h of exposure, respectively. Our findings indicate that each zona of the adrenal cortex and the two cell types of adrenal medulla show a differential reaction to noise stress. PMID- 9364809 TI - Visualizing the expression of a human growth hormone (hGH) transgene in the liver: intrahepatic regional and intracellular differences of expression are associated with morphological alterations and hepatocellular proliferation. AB - Growth hormone acts directly on liver cells; it binds to its receptor and induces a multitude of intracellular events leading, for example, to the production of insulin-like growth factor-1 (IGF-1). While much is known about the biochemical side of these events, their structural correlates are less well examined. Here, we examined livers of transgenic mice (TM) expressing human GH, in an attempt to correlate at the cellular level the site of GH gene expression with effects on morphology and mitotic behavior of liver cells within the hepatic architecture. Using in situ hybridization histochemistry we observed a striking expression pattern of the hGH gene in hepatocytes near the periportal spaces. In the same regions, the hGH protein, but no IGF-1 immunoreactive product, was detected using immunohistochemical methods. In the sections of TM livers, 6.8-31.9% of cells were hGH-immunoreactive. However, the cellular hGH staining pattern was not homogeneously distributed in the immunoreactive cells. Two main patterns became obvious. In the majority of the immunoreactive cells a cytoplasmic stain was present. These cells exhibited normal liver cell features and were not enlarged (type I). In the other group (type II), the staining was stronger and concentrated, sometimes punctuate, and often confined to cytoplasmic compartments which were in a perinuclear position. The latter staining pattern was generally seen in morphologically altered cells, which were enlarged and possessed intranuclear inclusions and invaginations. In the the periportal regions, mitotically active hepatocytes were evident, but these cells, as judged from immunocytochemistry, apparently did not express the transgene. In conclusion, different staining patterns for hGH may indicate different levels of transgene expression, which could be associated with difficulties in the cells with regard processing and/or secreting the hormone. In addition to the endocrine actions implied by the high hGH levels in the peripheral circulation of these TM, intracrine actions are also suggested (type II staining pattern), but para- and autocrine loops are possible as well (type I staining pattern). Whether IGF-1 is involved, and the mechanism underlying hepatocyte cell proliferation, remain to be examined. PMID- 9364810 TI - [Relationship between streptomycin susceptibility and rpsL mutations of Mycobacterium tuberculosis strains]. AB - The relationship between streptomycin (SM) susceptibility and rpsL mutations of Mycobacterium tuberculosis strains was studied. Of 18 clinically isolated SM resistant M.tuberculosis strains, mutation was suspected in 9 strains (50%) with SM MICs of > or = 256 micrograms/ml by PCR-single strand conformation polymorphism targeting rpsL gene. On the other hand, using PCR-direct sequence method, amino acid substitution caused by single nucleotide point mutation in rpsL gene was demonstrated in 11 out of 18 strains (61%). The same amino acid substitution at codon 43 (Lys-->Arg) was observed in all 11 strains with SM MICs of > or = 256 micrograms/ml. In addition, PCR products obtained from these 11 strains could not be cut by a restriction enzyme, Mbo II, while H37Rv strain and the other 32 strains with SM MICs of < 256 micrograms/ml were cut into 2 fragments. In conclusion, our results suggest that highly SM-resistant M.tuberculosis strains with MICs of > or = 256 micrograms/ml could be rapidly and easily detected by the restriction enzymatic method. PMID- 9364811 TI - [An autopsy case of severe tuberculosis associated with anal fistula and intestinal perforation]. AB - A 55 year-old man was admitted to the department of the gastroenterology of the hospital because of severe weakness and appetite loss for the past one month. In the last two months, he has been suffering from recurrent fistula of the anus. He left his symptoms without therapy. A gastric ulcer was found out with gastric endoscopy. At the same time, chest X-ray film showed bilateral abnormal shadows, which were suspected of severe pulmonary tuberculosis by a chest physician. After the admission, the patient immediately developed respiratory failure. Both sputa and discharge from anal fistula were positive for acid fast bacillus. Despite of anti-tuberculosis therapy and mechanical ventilation, he died of respiratory failure. At the autopsy, severe pulmonary tuberculosis, tuberculous fistula of the anus, intestinal tuberculosis with perforation, miliary tuberculosis and peptic ulcer of the stomach were defined. We suspected that the extensive disease caused by hematogeneous spread and the late diagnosis of tuberculosis was owing to patient's delay. PMID- 9364812 TI - [Respiratory failure in pulmonary tuberculosis sequelae]. AB - Patients with respiratory failure based on pulmonary tuberculosis sequelae are second in number among some fifty thousand patients receiving home oxygen therapy in Japan. Its 5 year survival rate is 47% in man and 56% in woman. The prognosis is better in woman than in man and may be dependent, at least partially, on younger age in woman. The influence of arterial blood gases on the prognosis is quite different between tuberculosis sequelae and chronic obstructive pulmonary disease: PaO2 scarcely influence the prognosis while higher PaCO2 is beneficial for tuberculosis sequelae. Patients with hypercapnia have better nutrition as estimated by serum albumin and this fact may cause the longer survival. Pulmonary hypertension is more frequently observed but is less strongly related to arterial blood gases and ventilatory function in tuberculosis sequelae than chronic obstructive pulmonary disease. PMID- 9364813 TI - [Biocompatibility of biomaterials used in dentistry]. PMID- 9364814 TI - [Clinical study of occlusal forces on dental implants]. AB - The object of this investigation was to analyze occlusal force in patients applied an implant-supported prosthesis. The occlusal force was measured on four free end saddle patients applied 10 dental implants (F. E.) and two bounded saddle patients 4 dental implants. The pressure sensitive sheet and the image scanner (Dental Prescale 50H type R and Occluzer FPD 703, Fuji Photo Film Co.) were used. The occlusal force (O. F.) occurred in implanted portion was almost the same as that on a natural tooth. O. F. and O. F. bearing rate (B. R.) on the posterior dentitions applied implants tended to increase toward the distal side. The total O. F. had a tendency to increase after applying implant-supported prosthesis, and comparing implanted side with non-implanted (natural teeth) side, B. R. was equilibrium. On the other hand, occlusal contact areas, O. F. and B. R. were decreased at the most distal tooth of residual dentition on the implant side of F. E. PMID- 9364815 TI - [A molecular mechanism of retinoblastoma protein (pRB) in neuronal differentiation of PC12 cells]. AB - In order to investigate the molecular mechanism of the retinoblastoma protein, pRB, in neuronal differentiation, the accumulation of the hypophosphorylated pRB in PC12 cells stimulated by nerve growth factor (NGF) was measured by the western blotting method. NGF induced the accumulation of the hypophosphorylated pRB in 30 min. and maximized the level at 12 h. Viral Ki-ras constitutively induced hypophosphorylation of pRB. A dominant negative form of c-Ha-ras suppressed the induction of the hypophosphorylation of pRB by NGF, but not by cAMP. This result is consistent with the idea that NGF induces hypophosphorylation of pRB through the Ras signaling pathway. The reduction of cdk2 activity caused by increment of p21 inhibitor may be a mechanism for hypophosphorylation of pRB. Furthermore, microinjection of a monoclonal antibody for the hypophosphorylated pRB blocked the neurite outgrowth initiated by NGF. It was also found that Hsc 71 interacted with hypophosphorylated pRB in vitro as well as in vivo in neuronal PC12 cells stimulated by NGF. These results suggested the dual role of pRB in the withdrawal of cells from the cell cycle and neuronal differentiation in PC12 cells. PMID- 9364816 TI - [Study on CAM system for dental model]. AB - The purpose of this study was to introduce our newly-developed CAM system for dental model and to examine the shape reproducibility and measurement reliability of the CAM modelling. The system is composed of a measuring unit, which obtains three-dimensional shape information from the dental model using laser scanning, and an engineering workstation, which creates a three-dimensional graph of the dental model. Output module program which can directly process and output the three-dimensional shape data to the wide use modeling systems was developed as the software of this CAM system. Four different CAM models, that, WAX model, STL model, FDM model, and SL model, were made based on the graph of the dental model taken from a mandibular prognathic patient. The measurement reliability of each CAM model were evaluated using a contact three-dimensional measurement unit. All CAM models except a WAX model demonstrated good shape reproducibility without a blind area, suggesting no problem of the three-dimensional shape data and the output module program. Measurement reliability of each CAM model was 0.12 +/- 0.08 mm in graph, 0.25 +/- 0.05 mm in WAX, 0.28 +/- 0.16 mm in SL, 0.31 +/- 0.15 mm in FDM, and 0.39 +/- 0.18 mm in STL. These results suggested clinical feasibility of this system in accordance with electronic storage of medical information. PMID- 9364817 TI - [Anterior occlusal contact of complete denture during mastication]. AB - The purpose of this study was to measure the actual anterior occlusal contacts in complete denture during mastication and discuss the relation between anterior occlusal contacts and masticatory movements. The actual anterior occlusal contacts were measured electrically with metal occlusal surfaces in five edentulous patients. These metal occlusal surfaces could be removed and changed into two types of occlusion. The masticatory movements were measured by Sirognathograph for seven edentulous patients. The types of anterior and posterior occlusions were changed, and the masticatory movements were analyzed for each of the four types of occlusion. The results were as follows: 1. Anterior occlusal contacts were found during mastication, but not during tapping, in bilateral balanced occlusion. 2. The frequency of anterior occlusal contacts during mastication was increased in non-balanced occlusion. 3. The frequency of occlusal contacts at the canine on the chewing side was increased by continuing of mastication, but was not increased at the canine on non-chewing side. 4. The stability of the denture tended to be lost by eliminating the anterior occlusal contact, judging from the rhythm of masticatory movements. This study suggested that anterior occlusal contacts are necessary for the functional harmony of complete denture during mastication. PMID- 9364818 TI - We need to know what is happening to the incidence of leprosy. PMID- 9364819 TI - Leprosy by the year 2000--what is being eliminated? PMID- 9364820 TI - Women and leprosy: a review. AB - Gender inequalities in health have a significant impact on women's health. In leprosy gender inequalities could be even more serious, as it is a highly stigmatized disease. A review has been made of the most recent literature dealing with gender and leprosy. First some data are presented on gender inequalities in rates of case detection, deformities and reversal reactions among leprosy patients. Then the major factors contributing to those differences are discussed. The paper ends with some recommendations for further research on gender and leprosy. PMID- 9364821 TI - Influence of acetylator phenotype on the haematological and biochemical effects associated with dapsone in leprosy patients. AB - Methaemoglobinaemia and haemolytic anaemia were the principal side-effects observed in 30 leprosy patients undergoing long-term treatment with dapsone as a single drug or as part of multidrug therapy. Hepatic, pancreatic and renal evaluations showed no relevant clinical changes. Since N-acetylation is a major metabolic pathway for dapsone, slow acetylation phenotype may be a risk factor for the development of these reactions. To confirm this hypothesis we correlated acetylator phenotype and the haematological and biochemical effects induced by dapsone. No excess proportion of slow acetylators was found. We conclude that slow acetylators are not at greater risk of developing haematological side effects of dapsone than fast acetylators. PMID- 9364822 TI - Clinical and histopathological activity in paucibacillary leprosy patients after fixed-duration multidrug therapy. AB - In 37 clinically-diagnosed borderline-tuberculoid (BT) leprosy patients skin biopsies were done prior to starting multidrug therapy (MDT) and at the end of 6 months therapy. Clinical and histopathological activity, graded as active, resolving and inactive, were studied at the end of 6 months of MDT. Of the 37 clinically-diagnosed BT patients 24 could be confirmed by histopathology as having BT leprosy, while the other 13 biopsies showed features of indeterminate (I) leprosy. After 6 months of MDT, out of the 24 histopathologically-confirmed BT patients, 4 (17%) showed clinical activity and 8 (33%) showed histopathological activity. Of the 13 histopathologically-diagnosed indeterminate cases all were clinically inactive but histological activity persisted in 3 cases (23%). Out of the 37 clinically-diagnosed BT patients 3 showed both clinical and histopathological activity at the end of MDT. This study emphasizes the importance of performing histopathological examinations on leprosy patients undergoing research studies for the confirmation of diagnosis and for proper classification of the disease. The histopathological activity that outlasts the MDT may be due to the bacillary fragments that persist but clinical activity coupled with histopathological activity seen in 3 patients at the end of 6 months may foreshadow a relapse and these patients and others like them need to be followed up for longer durations. PMID- 9364823 TI - Study on the detection of leprosy reactions and the effect of prednisone on various nerves, Indonesia. AB - This paper presents a retrospective study on the detection of the treatment of leprosy reactions in a field situation, and the effect of prednisone on the various affected nerves. Two patient cohorts were analysed. The leprosy control programme in the testing area is not backed up by a specialized referral leprosy hospital, but patients are treated on an ambulatory basis at peripheral health centres by trained multipurpose health workers supervised by the health centre doctors. For operational purposes the guidelines and procedures for reaction management in the field were adjusted and partially simplified. In both studies it appeared that the time of the occurrence of severe reactions was the same: 80% or more of the severe reactions occurred in the first year of treatment, the majority in the first few months after the start of the multidrug (MDT) treatment. One third of all reaction patients suffered from a silent neuritis. Well-instructed fieldworkers proved to be competent in detecting and treating leprosy reactions. Treatment of severe reactions with prednisone in the field situation can preserve or considerably improve the functions of the affected nerves. It is interesting that often the motor function of a nerve was found to be impaired without any loss in sensibility, which was tested using the ballpoint pen method. PMID- 9364824 TI - Does clofazimine have a prophylactic role against neuritis? AB - A study was undertaken with the aim of testing the usefulness of clofazimine as a prophylactic agent against neuritis and nerve damage. A modified regimen, using initial high doses of clofazimine followed by regular multibacillary multidrug therapy (MB-MDT) WHO regimen, was given to a series of consecutive cases of high risk borderline leprosy patients, fulfilling defined selection criteria (n = 65). These patients were studied for the incidence of neuritis/Type I reaction, over a period of 2 years. Results were compared with a matched series of consecutive cases treated only with regular MB-MDT WHO regimen (n1 = 57). The difference in incidence rates of neuritis between the two groups was significant (p < 0.01), suggesting that clofazimine may have a useful prophylactic role against neuritis/Type I reaction and nerve damage. PMID- 9364825 TI - Excretion of clofazimine in human milk in leprosy patients. AB - Clofazimine is an important and effective constituent of multi drug therapy for leprosy. A study has been conducted to determine the distribution of clofazimine in maternal milk so that the safety of breast-feeding during maternal ingestion of the drug can be ascertained. Eight female leprosy patients (LL/BL) on clofazimine, 50 mg daily or 100 mg on alternate days for 1-18 months, (mean 5.0 +/- 1.81 months; median 3.25 months) and in the early lactating phase were studied. Blood samples and milk specimens were collected 4-6 hr after the last daily dose. Clofazimine was assayed in the milk and plasma samples by HPTLC. Mean plasma and milk clofazimine levels were 0.9 +/- 0.03 micrograms/ml and 1.33 +/- 0.09 micrograms/ml respectively. The ratio of milk to plasma drug concentration ranged from 1.0 to 1.7 with a mean of 1.48 +/- 0.08. The amount of drug ingested by the infants was 0.199 +/- 0.013 mg/kg/day which represented 22.1 +/- 1.9% of the maternal dose. PMID- 9364826 TI - Atypical post-kala-azar dermal leishmaniasis resembling histoid leprosy. AB - An adult male with atypical lesions of post-kala-azar dermal leishmaniasis (PKDL) is described. He had extensive ulcerated noduloplaque lesions on his hands, feet and genitalia. He had been diagnosed and treated for leprosy in the past. He came from an area endemic for kala-azar and leprosy and had a previous history of kala azar. There was an abundance of Leishman Donovan bodies in slitskin smears and in histopathology sections. There was a good therapeutic response to sodium stibogluconate. An ulcerative variant of PKDL has been described but is extremely rare. Extensive lesions with ulceration have not been described before to the best of our knowledge. The epidemiological significance of the case is discussed. PMID- 9364827 TI - Sensory testing of the hands in leprosy. PMID- 9364828 TI - Unrecognized ocular morbidity in leprosy. PMID- 9364829 TI - Silicone breast implants and connective tissue disease: an overview. AB - Silicone breast implants have been implicated in the possible pathogenesis of various connective tissue diseases. These findings have had a major impact not only on the medical and legal communities, but also on the community at large. In this communication, we review the history of the breast implant controversy, and examine the medical evidence regarding the possible link of silicone gel implants with connective tissue disorders such as scleroderma, rheumatoid arthritis, and lupus. Finally, we give a broad overview of the topic and offer some general suggestions regarding the care of patients who have silicone breast implants. PMID- 9364830 TI - The utility of CT scanning in diagnosing dementia. AB - Dementia is an illness that affects an estimated 10% of noninstitutionalized persons older than 65 years of age. Among those older than 85 years of age, dementia is estimated to affect 20 to 50% of the population. The diagnosis of Alzheimer's disease is based on clinical criteria and the exclusion of other causes of dementia. Neuroimaging procedures, mostly CT scans, have been used to exclude other lesions presenting as dementia. The yield of these procedures has been estimated to be about 3%. This article reviews some of the literature on this topic in an effort to establish specific recommendations for neuroimaging procedures in patients who present with dementia. PMID- 9364832 TI - Acute gouty sacroiliitis: a case report and review of the literature. AB - A 45-year-old black woman with an acute attack of severe unilateral sacroiliitis, negative microbiologic studies, is presented. An open biopsy specimen of the sacroiliac joint revealed evidence of tophaceous gout. The unique features of the case, differential diagnosis, and pertinent literature on gouty sacroiliitis are reviewed. Acute gouty sacroiliitis, although it is rare, does occur and should be included in the differential diagnosis of unilateral sacroiliitis in patients with a long-standing history of gout. PMID- 9364831 TI - Antiphospholipid antibody syndrome: an acquired cause of venous and arterial hypercoagulability. AB - Antiphospholipid antibody syndrome is a major acquired cause of both venous and arterial hypercoagulability. Recent advances in the understanding of antiphospholipid antibodies, their detection, clinical presentations, and management are reviewed. PMID- 9364833 TI - Extended-interval dosing of aminoglycosides. AB - Aminoglycosides are efficacious agents. Their use has declined partly because of the development of newer, presumably less toxic agents. Research shows that aminoglycosides can be dosed differently than in the past, maintaining efficacy while reducing aminoglycoside toxicities. Aminoglycosides administered with newer agents may help overcome antibiotic bacterial resistance and thus yield safe and more effective therapy. This study focused on the efficacy and safety of the aminoglycosides extended-interval dosing regimen and was conducted by a search of the literature. Data from The Mount Sinai Hospital regarding bacterial resistance patterns were collected. A nomogram describing the administration of the extended interval dosing regimen is provided. Extended-interval dosing of aminoglycosides is as efficacious as administering these agents every 8 hours and may result in lower rates of toxicities. Extended-interval dosing also may cost less and be easier to administer. Aminoglycosides are less susceptible to bacterial resistance than many of the newer, currently favored antibiotics. Increasing the usage of aminoglycosides is likely to be safe and beneficial in the treatment of certain bacterial infections. PMID- 9364834 TI - Pediatrics at Mount Sinai. AB - The Department of Pediatrics at The Mount Sinai Hospital was founded more than 120 years ago. During the ensuing years it had five outstanding leaders, Drs. Abraham Jacobi, Henry Koplik, Bela Schick, Horace Hodes, and Kurt Hirschhorn. The evolution of its beginning as a "small" clinic to its present position as one of the outstanding pediatric centers in this country reflects its interest in and devotion to the care of children. PMID- 9364835 TI - Current trends in onychomycosis therapy: a literature review. AB - Problems with the use of griseofulvin and ketoconazole in the treatment of onychomycosis have led to studies of three new oral antifungal drugs to treat this disease: fluconazole, itraconazole, and terbinafine. These drugs have been superior in relation to a high rate of cure, shorter duration of treatment, minimal adverse effects, and prolonged duration of remission. Although both fluconazole and itraconazole are structurally related to ketoconazole, their triazole ring is more site-specific than the imidazole ring of ketoconazole, which makes these newer drugs less likely to cause liver toxicity. Terbinafine belongs to a new class of compounds called the allylamines, which are fungicidal rather than fungistatic. Terbinafine has become the first line of therapy in Europe and Canada for onychomycosis, and it has recently been approved in the United States in oral form. Itraconazole and fluconazole are available in the United States, but fluconazole is not yet approved for treatment of onychomycosis. PMID- 9364836 TI - Anemia secondary to low erythropoietin in a patient with normal renal function. AB - Anemia with a relatively low erythropoietin level has been described in several medical conditions associated with chronic inflammatory diseases such as rheumatoid arthritis, cancer, sickle cell disease, chronic renal failure, acquired immunodeficiency syndrome, and severe autonomic nervous system failure. This case report describes the development of anemia with a relatively low erythropoietin level in a 65-year-old man with non-insulin-dependent diabetes mellitus, normal renal function, and negative hematologic, thyroid, and autoimmune disease work-ups. The serum erythropoietin level was 14 mU/mL (N: 10 20 mU/mL). The hemoglobin was 7.5 g/dL and the hematocrit was 24%. The patient was treated with recombinant erythropoietin at 50 U/kg subcutaneously three times weekly. The hemoglobin level increased over a 4-week period. When erythropoietin was stopped, the anemia recurred in 2 months. We conclude that the patient's anemia was caused by a relative lack of endogenous erythropoietin release. The exact mechanism of this anemia is unknown. We recommend including a test for erythropoietin level in the evaluation of any unexplained anemia. PMID- 9364837 TI - Screening for Lyme disease in hospitalized psychiatric patients: prospective serosurvey in an endemic area. AB - BACKGROUND: Nervous system involvement in Lyme disease may mimic certain psychiatric disorders. We studied whether it is worthwhile to conduct routine screening of psychiatric inpatients for serologic evidence of Lyme disease. METHODS: Between March 1988 and June 1989, we prospectively screened sera for Lyme disease from adults admitted to an acute care psychiatric hospital in Westchester County. New York, an area in which this infection is endemic. Of all cases of Lyme disease reported to the U.S. Public Health Service in 1988, 16% originated in Westchester County. The prevalence in healthy blood donors from this area were reported to be 0.7%. Sera were tested by fluorescent immunoassay alone (90%) or fluorescent immunoassay plus enzyme-linked immunosorbent assay (10%). RESULTS: Sera from only 1 of 517 patients demonstrated antibodies to Borrelia burgdorferi, the etiologic agent of Lyme disease (0.2% [95% CI, 0.0% to 1.1%]). This patient had a nonreactive Western blot, which suggested a false positive antibody test. CONCLUSIONS: We cannot presently recommend routine serologic screening for Lyme disease for adult psychiatric inpatients, even in areas of the United States where this illness is endemic. PMID- 9364838 TI - The imperative to heal in traditional Judaism. PMID- 9364840 TI - Lyme disease. PMID- 9364839 TI - Onychomycosis vs psoriasis. PMID- 9364841 TI - Pulmonary and skeletal tuberculosis. PMID- 9364842 TI - [Significance of neoadjuvant therapy for prostate cancer]. PMID- 9364843 TI - [Establishment and characterization of a renal carcinoma cell line producing erythropoietin (effects of cyclic AMP on erythropoietin production in vitro)]. AB - BACKGROUND & METHODS: A cell line obtained from a primary lesion of renal cell carcinoma was newly established and observed to produce erythropoietin (Ep) continuously in vivo as well as in vitro. The histopathological and biological characteristics of this cell line were then analyzed in parallel with a study initiated on the role of cAMP on Ep production. RESULTS: The cells were subsequently serially transplanted into nude mice. The levels of Ep and hematocrit in the mice were found to correlate very closely with the tumor size. The histology of the xenograft was similar to the original tumor cells which constituted a nearly clear cell type and was immunostained positively for Ep. Ultrastructurally, Ep was localized in the perinuclear space, with part of the rough surface of the endoplasmic reticulum. In vitro, the cells grew exponentially with an approximate population doubling time of 2 days. The mRNA of Ep was detected using the RT-PCR method. The number of chromosomes in the cells ranged from 117 to 147 and featured complicated rearrangements and marker chromosomes. Forskolin, a well-known activator of adenylate cyclase which in turn generated the accumulation of cyclic AMP, produced a significant dose-related enhancement of Ep biosynthesis both in the cells and in the spent culture medium. CONCLUSIONS: Based on the results derived from the foregoing analysis of this new cell line, cAMP was found to play a salient role both in Ep biosynthesis as well as in Ep release. PMID- 9364845 TI - [Preoperative localization of enlarged parathyroid glands by 99mTc-MIBI scintigraphy]. AB - BACKGROUND: Recent studies have shown that 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI), a new agent for myocardial perfusion imaging, can be successfully applied to parathyroid imaging. We evaluated the efficacy of 99mTc-MIBI scintigraphy for preoperative localization of enlarged parathyroid glands in patients with hyperparathyroidism. PATIENTS AND METHODS: From June 1994 to September 1996, 24 patients with biochemical confirmation of hyperparathyroidism were studied with 99mTc-MIBI scintigraphy prior to operation. Eleven patients had primary hyperparathyroidism (PHPT) and 13 had secondary hyperparathyroidism (SHPT) associated with chronic renal failure, including one patient with recurrent disease after subtotal parathyroidectomy. A positive 99mTc-MIBI scan for an enlarged gland was defined as an area of persistent focal uptake on the delayed image acquired at 150 min after intravenous injection of 600 MBq of 99mTc MIBI. RESULTS: Of 11 patients with PHPT, 10, were found to have solitary parathyroid adenomas at surgery and one patient had primary hyperplasia. 99mTc MIBI scintigraphy accurately detected 9 of 10 adenomas and 2 of 3 hyperplastic glands with no false positive results. Both of the two glands that were not detected by 99mTc-MIBI weighed 200 mg. The mean weight of the 11 glands that were visualized was 1264 mg (range 300 approximately 4300 mg). The sensitivity and predictive value positive for PHPT were 84.6% and 100%, respectively. In 13 patients with SHPT, all of 49 parathyroid glands were identified during surgery, with 43 hyperplastic glands and 6 normal-size glands. Of 43 hyperplastic glands, 28 were detected by 99mTc-MIBI and there was significant difference between the mean weight of these 28 glands (999 mg, range 290 approximately 2630 mg) and that of the 15 nonimaged hyperplastic glands (283 mg, range 90 approximately 540 mg). None of the six normal glands were imaged with 99mTc-MIBI. One patient had a false positive scan caused by a thyroid nodule. The sensitivity and predictive value positive for SHPT were 65.1% and 96.6%, respectively. CONCLUSION: 99mTc MIBI scintigraphy is an excellent imaging method for localization of enlarged parathyroid glands in patients with hyperparathyroidism, especially with PHPT. However, it has the difficulty to demonstrate enlarged glands smaller than 300 mg in weight. PMID- 9364844 TI - [Maximum increase of penile circumference as a parameter for evaluation of penile erectile capacity]. AB - PURPOSE: Male erectile capacity has been often evaluated with the maximum changes of penile circumference during nocturnal penile tumescence (NPT) by erectometer. However, it has not been fully established that the changes actually reflect penile rigidity. In this paper, we evaluated how the maximum change (the increase in circumference or its rate) of the circumference is related to penile rigidity. PATIENTS AND METHODS: The study included 116 men with or without complaints of sexual dysfunction. The maximum increase (penile circumference on erection-that when flaccid) and increase rate ?(penile circumference on erection-that when flaccid)/penile circumference when flaccid? of penile circumference and penile rigidity were studied during artificial erection induced by intracavernous injection of vasoactivedrugs. RESULTS: When the maximum increase of penile circumference on erection was 21 mm or more, more than 80% of men achieved adequate rigidity of the penile for vaginal penetration. However, if the increase was 10 mm or less, all men had poor rigidity. In men having an increase of 11 mm or more and less than 21 mm, more than 80% did not achieve adequate rigidity if their penile circumference in the flaccid state was less than 95 mm. In contrast, 80% or more of the men showed penile rigidity sufficient for vaginal penetration when the flaccid circumference was 95 mm or more. Studies on the maximum increase rate revealed results similar to those in the study on the maximum increase. These two parameters had a similar diagnostic accuracy for evaluating penile rigidity. CONCLUSIONS: A higher prediction rate for penile rigidity was achieved by adding the parameter of penile circumference in the flaccid state to the maximum increase or increase rate of penile circumference. Thus, evaluation of erectile capacity by maximum changes (the increase in circumference or its rate) of penile circumference with an erectometer can be used for screening of men with sexual dysfunction. PMID- 9364846 TI - [A trial of laparoscopic assisted radical nephrectomy]. AB - BACKGROUND: We tried a new procedure of gas-less laparoscopy assisted radical nephrectomy. METHODS: Prior to insertion of laparoscope, pararectal incision approximately 7 cm in length was made to enter into the intraabdominal cavity. A 12 mm trocar was placed just below the umbilicus and a flexible electroscope was inserted through it. A 10 cm size disposable fan for lifting up the abdominal wall was indwelled through the under space of trocar port. After appropriately lifting up the abdominal wall, a 10 mm trocar for working channel was placed at mid-axillar line. Under laparoscopic and trans-laparotomic views, radical nephrectomy was performed using the combined technique of laparoscopic and open surgery. RESULTS: Seven patients have been successfully treated with this procedure. The mean operating time of this procedure was significantly shorter than that of totally laparoscopic nephrectomy. The recovery time from the operation was as short as usual laparoscopic nephrectomy. CONCLUSION: We thought that this procedure could open a new scope of laparoscopic surgery. PMID- 9364847 TI - [Clinical evaluation of scintigraphy and tumor biopsy for incidentally detected adrenal masses]. AB - PURPOSE: A decision tree in diagnosis of incidentally detected adrenal masses (incidentaloma) was made on the basis of these results. METHODS: The clinical usefulness of adrenal scintigraphy with 131I-adosterol and ultrasonically guided tumor biopsy was investigated in 44 patients. RESULTS: Adrenal scintigraphy was performed in 32 patients, of whom 21 were found to have an increased uptake in the tumor, including 19 cases of cortical adenoma and 2 of hematoma. No abnormal uptake was found in the remaining 11 patients, including 2 of cortical adenoma, 1 of adrenocortical oncocytoma and 8 of non-cortical tumors. Adrenal scintigraphy was thus thought to be useful in the differentiation of cortical tumor from non cortical tumor, showing the sensitivity of 86%, the specificity of 80% and the diagnostic accuracy of 84%. Cytological or histological study on specimens obtained by percutaneous adrenal tumor biopsy was performed in 19 patients, of whom 18 (95%) were correctly diagnosed in terms of the malignancy of incidentaloma. CONCLUSIONS: Taken together, the differential diagnosis and the surgical indication of adrenal incidentaloma could be made successfully based on adrenal scintigraphy and tumor biopsy. PMID- 9364848 TI - [Laparoscopic investigation of 74 cases of nonpalpable testis]. AB - BACKGROUND: The objective of this study is to evaluate the results and advantages of laparoscopic investigation of nonpalpable testis. METHOD: Since March 1986 to May 1996, we performed laparoscopy to investigate 88 nonpalpable testes of 74 cases under general anesthesia. On condition that testis was found intraabdominally, orchiectomy or orchiopexy was performed subsequently. With a finding of vas deferens and/or spermatic vessels entering into internal ring, inguinal canal was explored surgically. If both vas deferens and spermatic vessels were absent or blind-ending intraabdominally, no further examination was performed with a diagnosis of vanishing testis. RESULTS: Location of testes found in this study were as follows. Twenty three (26.1%) testes were found intraabdominally, 36 (40.9%) were intracanalicularly, 13 (14.8%) were distal to external inguinal ring, and 16 (18.2%) were vanishing testes. To those 39 (44.3%) intraabdominal and vanishing cases did not need inguinal exploration. CONCLUSION: In conclusion, a laparoscopic examination for nonpalpable testis is the most effective and less invasive procedure to make sure or preclude the location of the gonad. And in 18% of those who were enrolled in this study, no further surgical interventions were needed. An accurate locating of nonpalpable testis permits site-specific planning of surgical management. PMID- 9364849 TI - [Long-term follow up of patients with spina bifida--a review of 228 cases]. AB - BACKGROUND: The objective of this report is to evaluate the upper urinary tract changes of the patients with spina bifida who have been followed up for more than 10 years. METHODS: We analyzed 228 patients (97 males and 131 females) of spina bifida. Mean patient age was 18.7 years (10 to 51 years) and follow up period ranged from 10 to 27 years (mean 13.4 years). Upper urinary tract deterioration (Hydroureter and/or hydronephrosis), vesicoureteral reflux (VUR) and bladder deformity were investigated by excretory urography and voiding cystourethrography. We compared these 3 parameters in the initial and final examinations. RESULTS: In the initial examinations, upper urinary tract deterioration, VUR and bladder deformity were observed in 32.9%, 33.3% and 40.0%, respectively. During the follow up period, upper urinary tract was improved in 47.3% and VUR in 80.0%. Bladder deformity was disappeared in 14.4%. On the other hand, upper urinary tract was deteriorated in 9.3%. VUR and bladder deformity was newly developed or progressed in 8.0% and 29.3%, respectively. Finally, upper urinary tract deterioration, VUR and bladder deformity were observed in 31.3%, 18.2% and 52.0%, respectively. CONCLUSION: These results revealed that upper urinary tract and VUR were relatively controlled, however, bladder deformity was increased in its frequency. To prevent upper urinary tract deterioration, further analysis of sequential changes of urinary tract conditions should be demanded. PMID- 9364850 TI - [Evaluation of renal cystic mass on ultrasonogram and computed tomogram: usefulness of magnetic resonance imaging and renal angiography--category III by Bosniak: report of 5 cases]. AB - Bosniak classification of renal cystic massesis an extremely useful management tool. Of category I-IV by Bosniak, category III lesion is moderately complicated cyst, which cannot be confidently distinguished from malignancy radiologically. Here, we reviewed the clinical course of 5 patients with pathologically proven category III mass by Bosniak in order to evaluate the usefulness of magnetic resonance imaging (MRI) and renal angiography. Two of the 5 lesions were benign (hemorrhagic cyst) and the other were malignant (RCC). On MRI, the results of 5 lesions were true positive in 1 and false negative in 2. On angiography, the results were true positive in 2 and false negative in 1. MRI has an important role in detection of mass. Angiography is necessary for making a definitive diagnosis of the indeterminate renal cystic masses on US and CT as RCC, but cannot increase enough diagnostic confidence in small cystic renal masses. We experienced indeterminate 2 masses (case 1 and 4) on these four imaging techniques, which were RCC and hemorrhagic cyst, respectively. In category III lesions, if malignant finding was detected by MRI or angiography, we believe that surgical exploration should be performed. But, an absolute decision tree for management of the complicated renal cystic mass has not been published, and further investigation should be required. PMID- 9364851 TI - [Delineation of calf deep veins using 2D-TOF MR venography without contrast media: efficacy of tourniquet and leg-warming]. AB - We evaluated the imaging quality of 2D-TOF MR venography of the lower part of the leg and the efficacy of a tourniquet around the knee and leg-warming. In 8 healthy volunteers, MR venography was carried out under the following four conditions: (a) usual MR venography, (b) MR venography with tourniquet around the knee, (c) MR venography after leg-warming and (d) MR venography with tourniquet after leg-warming. Our results suggested that MR venography with tourniquet after leg-warming is best suited for imaging the veins of the leg. We also compared the diagnostic image quality of MR venography and conventional contrast venography in 7 patients with varices. The results showed no significant differences between the two methods. We conclude that MR venography with tourniquet after leg-warming is a technique that provides reliable information about the veins of the leg. PMID- 9364852 TI - [Retrospective analysis of prognostic factors for survival and intracranial control in postoperative radiotherapy for metastatic brain tumor: examination of localized field irradiation]. AB - To analyze the prognostic factors for postoperative radiotherapy of metastatic brain tumors, we retrospectively analyzed the clinical records of 127 cases that received more than 30 Gy of postoperative radiotherapy. The overall one-year survival rate (SR) was 48.2%, while the intracranial control rate (ICR) was 51.7%. Univariate analysis (UVA) revealed that female sex (p = 0.02), higher radiation dose (p = 0.05), and late onset (p = 0.05) were significantly favorable factors of SR. With multivariate analysis (MVA), the approving factors were higher radiation dose (p = 0.02), small number of metastases (p = 0.004), lesser extracranial metastasis (p = 0.02), and female sex (p = 0.02). In MVA, greater radiation dose (p = 0.004), lung cancer (p = 0.02), and late onset (p = 0.05) were found to be significantly good factors for ICR. Our unique method of localized field radiation as applied to well-resected and solitary metastatic tumors, was significantly correlated with better SR in this study. As long as patients are carefully selected, this technique is though to be useful for both the reduction of late complications and dose escalation in postoperative radiotherapy. PMID- 9364853 TI - [Relationship between redistribution rate (RD rate) of 123I-IMP SPECT and prognosis by Barthel index in cerebral infarction]. AB - A comparative study of RD rate and the Barthel index was performed in 26 patients who had cerebral infarction. On 123I-IMP SPECT, the RD rate was calculated as follows, RD rate = (I-II)/I x 100(%). (I = (B-A)/B, where A is the mean count of the low density area (LDA) on brain CT on the early image and B the mean count of the opposite portion of LDA on the early image. II = (B'-A')/B', where A' is the mean count of the LDA on the delayed image and B' is the mean count of the opposite portion of the LDA on the delayed image. delta Barthel index (delta B. I.) was defined as follows: delta B. I. = B. I. (post-rehabilitation)-B. I. (pre rehabilitation). In the group with B. I. (pre rehabilitation) < 85, the RD rate and delta B. I. were well correlated. In the group with B. I. (pre rehabilitation) > or = 85, the RD rate and delta B. I. were not correlated. This result suggests that the RD rate might be useful in predicting prognosis and selecting the principle of therapy. PMID- 9364854 TI - [Usefulness and limitations of 99mTc-MIBI scintigraphy for detection of parathyroid lesions]. AB - To evaluate the usefulness of MIBI scintigraphy (MIBI) for parathyroid lesions, the detectability of lesions by MIBI was compared with that by Tl-Tc subtraction imaging, ultrasonography, CT and MRI in 56 histologically proved lesions. In neck lesions, ultrasonography (92%) and MIBI (85%) showed better detectability than those by the other three modalities. With MIBI, detectability was decreased for smaller parathyroid lesions that coexisted with thyroid disease. Among the five modalities, MIBI showed the highest detectability (88%) for ectopic or metastatic lesions. The smallest parathyroid lesions detected by MIBI were a parathyroid adenoma weighing 220mg and a parathyroid hyperplasia weighing 200mg. MIBI was thought to be more valuable for ectopic or metastatic parathyroid lesions. PMID- 9364855 TI - [A new mechanically manipulated unit for CT-guided biopsy]. AB - To avoid radiation exposure to the radiologist during biopsy with CT fluoroscopy, we have developed a new system for CT-guided biopsy. The system is composed of three parts, a needle holder, arm and support. The automatic biopsy needle is mechanically remote controlled by flexible shafts with four functions. In the phantom study and the clinical trial, we were able to biopsy nodules under remote control with this equipment, eliminating radiation exposure to the radiologist. Although a few refinements of the system are necessary, it may enable us to perform CT-guided biopsy more safely and easily. PMID- 9364856 TI - [Early HCC and adenomatous hyperplasia: evaluation of arterial and portal blood flow with CTA, CTAP, and pathologic correlation]. AB - In order to analyze the hemodynamic properties of early hepatocellular carcinoma (HCC) and adenomatous hyperplasia (AH), three lesions (two HCCs, one AH) depicted as hypoattenuating at CTA and iso attenuating at CTAP were correlated with the histopathological findings. The number of normal hepatic arteries in the tumor was lower than in the liver. Degeneration and narrowing of the lumens were also seen microscopically. All tumors showed the replacing growth pattern and had similar numbers of the portal tracts in the tumor to the liver. The decreased number of intratumoral normal arteries is suspected to be a characteristic finding of the early stage of HCC. PMID- 9364857 TI - [Dynamic MR hepatocholangiography with the SIP Fast GRE (saturation inversion projection fast gradient echo) method]. AB - The purpose of this study was to assess the utility of dynamic MR hepatocholangiography with the Gd-EOB-DTPA enhanced SIP Fast GRE sequence in the hepatobiliary system. The SIP Fast GRE sequence was used for sequential imaging of the hepatobiliary system with a frame rate of 3 sec in a 256 x 192 matrix. Dynamic sequential acquisition was performed for 51 min before and after the injection of 30 mu mol/kg of Gd-EOB-DTPA in a rabbit. Dynamic images of the hepatobiliary system were obtained in the rabbit study. Dynamic MR hepatocholangiography provides better functional information than conventional MR cholangiography. PMID- 9364858 TI - [A case of ovarian fibrosarcoma]. AB - We report a case of ovarian fibrosarcoma, one of the least common gynecological tumors. The tumor was a well-circumscribed mass extending from the pelvis to the lower abdomen. The greater part of the tumor was composed of fluid consisting of hemorrhage, degeneration and necrosis. This appeared as a very high-intensity area on T2-weighted MR images. There were also solid portions in the tumor that were shown as enhanced lesions on contrast-enhanced CT. It should be noted that fibrosarcoma can appear as an area of high intensity on T2-weighted MR images, although it belongs to the fibroma-thecoma group. PMID- 9364860 TI - [Regional meetings of the Japanese Society of Otolaryngology. 1997. Abstracts]. PMID- 9364859 TI - [Stent-graft placement for saccular aortic aneurysm: case reports]. AB - Stent-graft placement was performed in 2 patients with saccular aortic aneurysm. A Dacron-covered nitinol stent-graft was deployed in the thracoabdominal and infrarenal abdominal aorta. These procedures were successfully performed. The aneurysm disappeared on intraoperative angiogram immediately after deployment. Follow-up CT showed thrombosis or disappearance of aortic aneurysm. Distal embolization occurred in one patient, who required resection of the small bowel on the following day and renal dialysis due to renal infarction. Both patients were still alive one and a half years and one year after the procedure, respectively. Stent-graft placement is a feasible alternative to surgery for aortic aneurysm in selected patients. PMID- 9364861 TI - [Alterations of the p53 gene and clinical features in childhood acute lymphoblastic leukemia]. AB - Correlations between alterations of the p53 gene and clinical features were examined in childhood acute lymphoblastic leukemia (ALL). We analyzed 147 patients and 38 cell lines for p53 mutations within exons 5 to 9 (2 to 11 in some of them) by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing. p53 gene mutations were found in 3 of 62 (5%) patients at diagnosis, 1 of 14 (7%) patients at relapse, and 13 of 20 (65%) cell lines in T-ALL, 2 of 20 (10%) patients at diagnosis, 4 of 4 (100%) patients at relapse, and 4 of 5 (80%) cell lines in t(1;19)-ALL, 1 of 23 (4%) patients at diagnosis, 2 of 22 (9%) patients at relapse, and 5 of 12 (42%) cell lines in common ALL other than t(1;19) or t(9;22)-ALL and 3 of 3 (100%) patients at diagnosis in B-ALL. In t(1;19)-ALL, p53 gene alterations were associated with a poor prognosis. The patients with p53 mutations had a trend towards poor prognosis in childhood ALL without B-ALL. p53 gene mutation is not always associated with the current prognostic factors. This alteration may become one of the important prognostic factors, if the detection of a small number of the leukemic cells with the p53 gene mutation would be possible. PMID- 9364862 TI - [Apoptosis in infectious mononucleosis]. AB - Apoptosis of lymphocytes in infectious mononucleosis (IM) was studied. Apoptotic cells (APCs) were defined by morphological characteristics, such as nuclear fragmentation, undergoing apoptosis. Among 10 of 27 IM patients (37.0%) APCs > or = 3 per 500 peripheral white blood cells were observed on admission, but not in normal individuals. Sequential changes of proportions of both APCs and atypical lymphocytes (examined in 2 cases) showed a similar pattern, although APCs began to appear somewhat later and peak level of APCs were lower in comparison with those of atypical lymphocytes. APCs were positive for both anti-T cell and anti Fas antigen monoclonal antibodies. Fas-positive cells were frequent in the early stage of IM, and returned to the normal range with the decrease of atypical lymphocytes. Sequential analyses of DNA fragmentation, done in one case, revealed that DNA fragmentation appeared with increase of APCs and disappeared with the decrease of APCs. These results suggest that apoptosis of T-cells in IM participates in the reconstitution of a proportion of lymphocytes disturbed by EB virus. PMID- 9364863 TI - [Treatment of acute lymphoblastic leukemia of young adults (15-22 years of age): results of co-operative study with internal medicine and pediatrics]. AB - Ten young adults (15-22 years of age) with acute lymphoblastic leukemia were treated with the protocol of internal medicine and pediatrics co-operative study group since 1989. All patients had complete remission within 5 weeks. Four of 6 patients of low risk group (less than 30,000/microliter of WBC count at diagnosis) and 1 of 4 patients of high risk group have continued the complete remission. Three patients relapsed in bone marrow (BM), and 2 patients in both BM and central nervous system (CNS). All patients could be treated without serious complications except for infection. We obtained the good results of treatment for the low risk group, but did not for the high risk group in this study. Little is known about acute lymphoblastic leukemia in young adults because these individuals are at the borderline age between internal medicine and pediatrics. Taken together with the psychologically distinct age of these patients, it is necessary to establish a closer relationship between internal medicine and pediatrics. PMID- 9364865 TI - [Myelodysplastic syndrome with monosomy 7 following combination therapy with granulocyte colony-stimulating factor, cyclosporin A and danazole in an adult patient with severe aplastic anemia]. AB - We report a case of severe aplastic anemia (SAA) treated with granulocyte colony stimulating factor (G-CSF), cyclosporin A and danazole, in which myelodysplastic syndrome (MDS) with monosomy 7 developed eight months later. A 24-year-old woman was diagnosed as having SAA and was initially treated with G-CSF, cyclosporin A and danazole. At initial presentation, bone marrow aspirate revealed marked hypocellularity with a normal karyotype (46, XX [20]) and no MDS features. Eight months after initial treatment, leukocytosis and reticulocytosis were observed and bone marrow aspirate showed hypercellular marrow with morphological and cytogenetic features (45, XX, -7 [16]/46, XX [4]) characteristic of MDS (refractory anemia). A total of 75 mg (1.25 mg/kg) of G-CSF had been administered during the preceding eight months. Among seven previous reports published in Japan since 1992, in which MDS/acute myelogenous leukemia (AML) developed from SAA treated with G-CSF, six showed monosomy 7. Careful observation for leukemic transformation is therefore indicated in patients with SAA who are treated with G CSF. PMID- 9364866 TI - [Rapidly progressed chronic myelomonocytic leukemia associated with severe skin infiltration]. AB - A 79-year-old man developed nodular skin eruption in his trunk in March 1995. He was diagnosed as CTCL and hospitalized to the department of dermatology and low dose VP-16 therapy was started. 6 months later, he was referred to our department because of severe melena. On admission, marked monocytosis was observed both in the bone marrow (43.6%) and peripheral blood (monocyte > 1,000/microliter). Skin biopsy showed infiltration of large mononuclear cells in the dermis and subcutaneous tissue. Thus a diagnosis of CMML with skin infiltration was made. Skin eruption developed over his entire skin and peripheral monocytes increased over 5,000/microliter. Chemotherapy was started and skin infiltration was slightly improved, but the disease developed into acute phase and he died 3 months after admission. PMID- 9364864 TI - [Prognosis in 75 cases of chronic lymphocytic leukemia and second malignancies]. AB - Clinical prognosis and analysis of causes of death of 75 CLL cases were evaluated. Median survival was 43.7 months. Major causes of death were infection (36%), primary CLL (16%), secondary malignancies (16%), cardiac failure (8%), brain hemorrhage (7%) and so on. There were 10 deaths (13%) with second or double cancers and 2 deaths with malignant lymphomas. In terms of deaths from CLL complicated by cancer, there were 4 deaths from stomach cancer, 3 from lung cancer, 1 from liver, pancreas, or prostata cancer. Cancer risk, which did not vary according to initial treatment category, was also constant across all time intervals after CLL diagnosis. PMID- 9364867 TI - [Diffuse large B-cell lymphoma mainly involving the heart and showing t(8;14) (q24;q32) with c-myc rearrangement]. AB - A 77-year-old man was admitted because of massive pericardial effusion and cardiac tumor. Cytological examination of the effusion and histological examination of a subcutaneous tumor in the chest wall revealed diffuse large B cell lymphoma. The immunophenotype of tumor cells was CD5+ CD20+ CD22+ CD38+ HLA DR+ CD19-. Chromosome analysis revealed complex abnormal karyotypes containing t(8;14) (q24;q32). C-myc gene rearrangement was shown by Southern blotting. Chemotherapy with pirarubicin, cyclophosphamide, vincristin, and prednisolone (THP-COP) was not effective for his lymphoma. He suffered from cardiac tamponade and died at 5 months after diagnosis. Autopsy revealed a large cardiac tumor, extensive epicardial infiltration, tiny tumors in the lung and pancreas, but no lymphadenopathy, the combination of which suggested a primary cardiac lymphoma. Immunohistochemistry for p53 protein showed nuclear staining of more than 50% of the lymphoma cells. In situ hybridization for EBER-1 was negative. Rearrangement of c-myc gene and overexpression of p53 protein are usually observed in Burkitt's lymphoma and some cases of high grade lymphomas including AIDS-associated non Hodgkin lymphomas. In this case the association of these molecular findings and resistance to chemotherapy is suggested. PMID- 9364869 TI - [A neonate born to a mother with acute promyelocytic leukemia treated by all trans retinoic acid]. AB - We report a female neonate delivered in week 32 of gestation by a mother who had acute promyelocytic leukemia (APL) treated by all-trans retinoic acid (ATRA). APL was diagnosed in week 29 of gestation and was treated with ATRA from week 30. Physical examination and laboratory tests showed no abnormalities at birth. The girl has since shown normal development, with no peripheral blood abnormalities at 2 years old. Hypersegmented neutrophils, which often appear during ATRA treatment, were seen in the peripheral blood of the mother and cord blood but not peripheral blood of the neonate on the day of birth. ATRA is known to cross the placenta, and has been revealed to be teratogenic in animal studies. There have been eight neonates born to the mothers with APL who were treated with ATRA during pregnancy. All infants, including this one, have shown normal growth without any complications. PMID- 9364868 TI - [Acute myeloblastic leukemia showing pronounced skin infiltration during administration of low-dose cytarabine and etoposide with granulocyte colony stimulating factor]. AB - A 26-year-old woman was admitted to our hospital for lumbago on November 29, 1995. The white blood cell count was 6,500/microliter with 26.5% myeloblasts and the bone marrow was hyperplastic due to myeloblasts. Myeloblasts were negative for myeloperoxidase and positive for alpha-naphthyl butylate esterase, CD11a (89%), CD11b (38%), CD11c (92%), CD33 (91%) and HLA-DR (58%). Chromosomal abnormalities were recognized: 46, XX, t(9;11) (p22;q23), 45, XX, -7, t(9;11) (p22;q23) and 47, XX, +19, t(9;11) (p22;q23). Acute myeloblastic leukemia (M5a) was diagnosed. Disseminated intravascular coagulation was also present. The patient received induction therapy and achieved remission on January 9, 1996, but myeloblasts increased to 3.6% in bone marrow despite consolidation therapy. Low doses of cytarabine (AraC) and etoposide were instituted on March 7, granulocyte colony-stimulating factor (G-CSF) was started on March 15, and pronounced skin infiltration developed on March 18. The patient received reinduction therapy from April 16 and administration of G-CSF was combined for 2 days, and a marked increment of myeloblasts in the peripheral blood was observed. After discontinuation of G-CSF, myeloblasts decreased and skin infiltration disappeared. However, the patient died of cerebral infiltration on June 30. The response of myeloblasts to G-CSF by in vitro liquid culture was noteworthy. The present case stresses the requirement for great caution to be exercised in the use of G-CSF in patients receiving low dose AraC. PMID- 9364870 TI - [Clonal analysis by fluorescence in situ hybridization in a patient with de nove acute myeloid leukemia with myelodysplasia]. AB - A 12-year-old girl presenting leukocytosis, anemia and thrombocytopenia was diagnosed as de nove acute myeloid leukemia (AML, M2) with concurrent myelodysplastic features in myeloid and erythroid cells. Her karyotype was defined as 47, XX, +8[20]. Though she was treated successfully with multi-drug chemotherapy, she relapsed after 2 years of remission. A bone marrow transplantation from HLA matched her brother was performed to induce hematological remission which persisted for one year. She again relapsed with AML with myelodysplasia, and an abnormal complex karyotype was newly detected. She eventually died without further chemotherapy. We performed FISH on the patient's stained bone marrow smears using DNA probes for chromosome 8 and Y to analyze the clonality. The results showed that the most of blasts and bone marrow cells except lymphoid cells were of trisomy 8 at onset, while in the 1st remission, trisomy 8 clone was slightly detected only in monocytes. At 1st and 2nd relapse, trisomy 8 clone was detected again in most of myeloid cells. Thus, in this case, it was considered that underlying stem cell disorder with trisomy 8 during the entire disease course contributed to leukemogenesis. PMID- 9364871 TI - [CD7+, CD34+, electronmicroscopically peroxidase-negative acute leukemia transformed from polycythemia vera after 12 years follow-up]. AB - We reported a 72-year-old female patient who developed acute leukemia following a long course of polycythemia vera (PV). For 12 years she had been treated with phlebotomy, nimustine, busulfan, hydroxyurea and irradiation on splenomegaly. In November 1995, her peripheral blood smear showed blast of 30%. Bone marrow blasts were microscopically as well as electromicroscopically peroxidase-negative and CD7 and HLA-DR positive. Six months later, the blasts were positive for CD7, CD34 and HLA-DR. On the basis of morphologic, biochemical and immunophenotypic features, the patient was diagnosed acute leukemia, probably arising at a primitive multipotential stem cell level. She failed to respond to the various combination therapy including prednisolone, vincristine, cytarabine, daunorubicin and etoposide. The stem-cell-leukemia transformation in PV occurs rarely and may be refractory to chemotherapy. PMID- 9364872 TI - [Allogeneic peripheral blood stem cell transplantation for multiple myeloma]. AB - We report here with a 46-year-old man with refractory multiple myeloma receiving allogeneic peripheral blood stem cell transplantation from his HLA-matched brother. The preparative regimen consisted of TBI (12Gy), VP16 (15 mg/kg) and cyclophosphamide (120 mg/kg). GVHD prophylaxis consisted of cyclosporin A and short course of methotrexate. The donor received G-CSF at 10 micrograms/kg/day for 5 consecutive days and underwent leukapheresis on days 5 and 6. The neutrophil recovery to 500/microliter and platelet recovery to 20,000/microliter were day 12 and day 15, respectively. The patient is currently well with no GVHD or graft failure and a complete donor's chimerism. PMID- 9364873 TI - [Successful treatment for advanced and refractory chronic lymphocytic leukemia with fludarabine phosphate]. AB - 53-year-old man with chronic lymphocytic leukemia resistant to alkylating agent containing regimens, was treated with fludarabine phosphate. Hematological data before the administration of fludarabine phosphate was as follows: RBC 216 x 10(4)/microliter, Hb 7.7 g/dl, WBC 69,400/microliter (lymphocyte 96%), PLT 0.2 x 10(4)/microliter. Bone marrow was fully occupied with lymphocytes. Red blood cells and platelets transfusions were frequently required. Fludarabine phosphate was administered at a dose of 40 mg (23 mg/m2) intravenously for 5 days every 4 weeks. After the start of the therapy, peripheral lymphocyte counts were markedly decreased and recovery of normal hematopoiesis was observed in bone marrow. Any transfusions were no longer necessary. Fludarabine phosphate may be active even for advanced, refractory and terminal stage chronic lymphocytic leukemia. PMID- 9364874 TI - [The sulfonylurea receptor]. PMID- 9364875 TI - [Structure and function of glucose transporters]. PMID- 9364876 TI - [Drug transporters in renal tubules]. PMID- 9364877 TI - [Primary active transporter responsible for the biliary excretion of xenobiotics]. PMID- 9364878 TI - [UDP galactose transporter]. PMID- 9364879 TI - [A role for GAPDH in neuronal apoptosis]. PMID- 9364880 TI - [Regulation of actin-based cytoskeleton in the neuronal growth cone]. PMID- 9364881 TI - Stillbirths. PMID- 9364882 TI - Optimising management of stillbirths in modern Singapore. AB - OBJECTIVE: To conduct a critical analysis of stillbirths in Kandang Kerbau Hospital with emphasis on epidemiological factors, related causes and investigation strategies. DESIGN: A prospective study. SETTING: Kandang Kerbau Hospital. PATIENTS: Case records containing antenatal and post-partum details of all 136 stillbirths were obtained from the medical records office and reviewed by 3 obstetricians. Epidemiological data, antenatal history, intrapartum progress, post-partum investigation, post-mortem findings (where applicable) were reviewed and recorded. RESULTS: The incidence of stillbirths was 4.48/ 1,000 in 1994. 73.1% of the stillbirths were macerated. Significantly higher stillbirth rates were noted in the Malays and unbooked or late booking cases. The causes of stillbirths were unexplained in 29.4%. Fetal anomalies constituted 18.4%, followed by asphyxia, abruptio, and cord accidents. Maternal obstetrical problems contributed to the rest. CONCLUSION: A comprehensive management strategy to reduce stillbirths include community and patient education, early or shared antenatal care, careful prenatal surveillance, optimum investigations as well as a careful audit with adequate bereavement and counselling. PMID- 9364883 TI - Effect of learning curve on the outcome of external cephalic version. AB - AIM: The aim of this study was to find out the effect of learning curve on the outcome of external cephalic version (ECV) at term, using tocolytics. The effect of various factors affecting the outcome of ECV was also studied in relation to the learning curve. METHODS: This is a prospective longitudinal observational study of 80 consecutive cases of ECV. They were analysed in relation to outcome, parity, type of breech, placental site and birth weight. The cases were divided consecutively into 4 groups of 20 cases each, in order to analyse the effect of learning curve. RESULTS: The learning curve for ECV is very sharp. The success rate of external cephalic version plateau after the first 20 cases from 45% to about 60%. Only parity and type of breech have a significant effect on the outcome. The success rate is lower for primipara and non-flexed breech. This negative effect is strongest in the first 20 cases and again plateaus after the first 20 cases. The high success rate of multipara and primipara flexed breech is obtained even in the first 20 cases and does not improve with further experience. CONCLUSIONS: The learning curve for ECV is sharp and plateaus after the first 20 cases. Outcome of ECV for patients with favourable factors such as multiparity and flexed breech is not affected by learning curve. PMID- 9364884 TI - Efficacy of bronchodilators in the treatment of bronchiolitis. AB - Bronchiolitis is a common respiratory infection affecting young children. Much controversy revolves around the efficacy of bronchodilators in the treatment of bronchiolitis. This study was conducted to address this issue. AIM: To determine the efficacy of bronchodilators in the treatment of bronchiolitis. METHOD: All children less than 2 years old with bronchiolitis were randomly assigned to receive nebulisations of Salbutamol, Ipratropium bromide or normal saline. A fourth group given only humidified oxygen without nebulisation were used as a control. RESULTS: Data were obtained for 120 patients. Fifty-one (42%) had respiratory syncytial virus (RSV) isolated from their nasopharyngeal aspirates. The demographic characteristics of the 4 groups were similar. There was no significant difference between the groups in terms of severity score, number of nebulisations required in the nebulised groups and the outcome as measured by the length of hospitalisation. CONCLUSION: The use of bronchodilators did not alter the course of the disease and is therefore not effective in the treatment of bronchiolitis. PMID- 9364885 TI - Chorda tympani trauma--how much does it affect taste? AB - The chorda tympani nerve runs just beneath the tympanic membrane, and is often traumatised or sacrificed during middle ear surgery. There is varied opinion as to whether surgeons should preserve this nerve, risking trauma to it in the process, or cleanly sacrifice it, which some authors claim produces less trauma and less troubling dysgeusia. We studied 31 patients retrospectively to document their taste change following middle ear surgery, and found that in many instances, taste change caused by the operation recovered in the course of time. However, when the chorda was sacrificed, there was a 31% increased incidence of permanent taste change. PMID- 9364886 TI - Anorexia nervosa and bulimia--a Singapore perspective. AB - OBJECTIVE: To study the clinical characteristics of patients with anorexia nervosa and bulimia. METHOD: Fifty patients presenting to our department from 1991-1996 were identified and studied retrospectively. RESULTS: There was an increase in presentations for anorexia and bulimia over the period studied. The majority exhibited body image disturbance, morbid fear of fatness and compulsive efforts to lose weight, not dissimilar to that described in the Western literature. Significant transcultural differences were not found. Those with significant binge eating were more likely to present at a later age, have a higher BMI, menorrhoea, associated vomiting and/or laxative use, have prominent depressive symptoms and a history of self-harm. Compared to anorexics, bulimics were more likely to have relationship stresses and a history of self-harm. CONCLUSION: The clinical characteristics of anorexics and bulimics are more striking for their similarities rather than differences to that described in the West. PMID- 9364887 TI - Initial experience with clozapine in Woodbridge Hospital. AB - OBJECTIVES: This study was performed to evaluate the efficacy and side-effect profile of the atypical neuroleptic clozapine in local Asian patients with treatment-resistant schizophrenia. METHOD: Patients were treated with 12 weeks of clozapine after undergoing a washout of all previous neuroleptics. They were assessed weekly on the Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression (CGI) and the Simpson-Angus Scale for Extrapyramidal Side-Effects. RESULTS: Clinical improvement (according to criteria established a priori) at study end point was shown in 78.9% of the patients. There was no statistical difference in the incidence of the extrapyramidal side-effects at starting and end points. The mean daily dosage was 356.6 mg. The most common adverse effect was hypersalivation. CONCLUSION: Clozapine is effective and well tolerated in local patients with treatment-resistant schizophrenia. PMID- 9364888 TI - Neuroimaging guidelines in cognitive impairment: lessons from 3 cases of meningiomas presenting as isolated dementia. AB - We report three cases of large intracranial meningiomas who presented with dementia alone and no accompanying focal neurological deficits. The meningiomas were detected solely as a result of a policy of routinely scanning the brains of patients presenting with early dementia. Dramatic improvements in the cognitive functions were noted following the excision of the tumours in two of the patients (the third passed away in the perioperative period). The implications of these cases with regard to deciding when to order a brain scan for patients presenting with isolated dementia are discussed in this article and a brief review of the relevant medical literature on this topic is also presented. PMID- 9364889 TI - Autologous bone marrow transplantation in a child with acute promyelocytic leukemia in second remission. AB - Acute myeloid leukemia (AML) comprises 15%-20% of childhood acute leukemia cases. The long-term disease free survival (DFS) in childhood AML is poor with standard chemotherapy alone. Early intensive chemotherapy is generally regarded to be necessary for achieving high complete remission (CR) rates. Recent experience has shown that incorporation of early intensification with high-dose melphalan conditioning and autologous bone marrow transplantation (BMT) during the first remission significantly improves long-term DFS in children with AML. In this article, we report the use of autologous BMT for treatment of a three-and-half year old child with acute promyelocytic leukemia (APL or M3) in second remission. The patient was conditioned with high-dose melphalan of 180 mg/kg prior to bone marrow reinfusion. A total of 4.0 x 10(7)/kg mononuclear cells and 1.07 x 10(5)/kg granulomonocytic colony forming units (CFU-GM) were infused. Haematopoietic stem cells were enriched by almost 20-fold after the separation and cryopreservation procedures. Haematological recovery was achieved four-and-a half weeks post-BMT. She has remained in complete remission 18 months after transplantation. Our experience in this patient indicates that this procedure can be used in second remission and it may provide a better alternative for the management of childhood AML in Singapore. PMID- 9364890 TI - Use of gallium-67 in the assessment of response to antibiotic therapy in malignant otitis externa--a case report. AB - Malignant Otitis Externa (MOE) can cause considerable morbidity and mortality in affected individuals. The outlook is now much improved with the use of ciprofloxacin, but it is important to ascertain that the infection has been completely eradicated before stopping treatment, as undertreatment may lead to a recurrence which is usually more resistant than the initial infection. Gallium-67 Single Photon Emmision Computerised Tomography (SPECT) is a sensitive and cost effective tool in monitoring the disease activity of MOE, and should be used in the assessment of the response to antibiotic therapy. PMID- 9364891 TI - Clinics in diagnostic imaging (28). AB - A 44-year-old man presented with sudden headache and neck stiffness. Computed tomography (CT) demonstrated subarachnoid haemorrhage. CT and magnetic resonance (MR) angiography showed the cause to be a ruptured anterior communicating artery aneurysm. These findings were confirmed by digital subtraction angiogram and at surgery. The role of imaging in detection of cerebral aneurysms is briefly discussed. PMID- 9364892 TI - What you need to know: weight-for-height reference charts for Singaporeans. PMID- 9364893 TI - A brief introduction to the early history of surgery in Singapore (Part III). PMID- 9364894 TI - History of Koro in Singapore. PMID- 9364895 TI - Critical conceptual and methodological considerations in reading intervention research. AB - Research designed to identify the instructional and ecological conditions that foster the development of literacy skills in children with reading disabilities reflects a complex, multivariate enterprise. In essence, such research must be able to ultimately identify the teacher characteristics and instructional components that are critical for individual children and the interrelationships among these components. The intensity and duration of instruction will differ according to the severity of deficits in either single- or multiple-component reading processes. Moreover, training in any one component may not be sufficient to produce automatic improvements in other reading skills. This article identifies a number of conceptual and methodological issues that should be considered when conducting and interpreting reading intervention research. PMID- 9364896 TI - NCAA college freshmen academic requirements: academic standards or unfair roadblocks for students with learning disabilities? AB - The National Collegiate Athletic Association (NCAA) has implemented sweeping legislation for all high school students who desire to participate in Division I or II freshman college athletics. Cutoff scores have been set by the NCAA in two areas: grade-point average (GPA) in "core" high school courses, and college-bound tests. High schools must obtain approval from the NCAA Initial-Eligibility Clearinghouse when determining core courses. Unfortunately, minimal attention has been given in the professional learning disability literature to the implications of the NCAA's policies, especially with regard to federal antidiscrimination legislation. Issues are raised regarding (a) the use of test score cutoffs, (b) a minimum GPA for core courses, (c) the responsibility of high schools, and (d) the lack of alternative eligibility procedures for accessing the essential elements of the NCAA's program. Options for consideration are provided in the context of meeting the needs of students with learning disabilities. PMID- 9364897 TI - State disparities in the diagnosis and placement of pupils with learning disabilities. AB - We investigated the hypothesis that interstate disparities in the diagnosis of pupils with learning disabilities (LD) are more strongly correlated with demographic and sociopolitical factors than with the biological prevalence of the disability. We also investigated the relationship of these factors to placement practices. Thirteen independent variables representing state characteristics were simultaneously regressed against each of seven static dependent variables, measuring diagnostic and placement practices in 1989, and two dynamic dependent variables, measuring changes in practices between 1976 and 1989. Results of the regression indicated that although demographic and sociopolitical factors explained none of the total prevalence of the four most common physical disabilities (adjusted R2[R2] = 0), they did explain to a moderate degree the state prevalence of LD (R2 ranged from .15 to .28), and were more predictive still depending on measure of LD prevalence. Moreover, these same factors strongly predicted the extent to which states mainstreamed their pupils (R2 = .59) and the size of the nonmainstreamed cognitively disabled (LD and educable mentally retarded) population (R2 = .56). PMID- 9364898 TI - High school graduation requirements for students with disabilities. AB - Although increasing the high school graduation rate is now a national goal, requirements for graduation are not set at the national level. And, although the goal is said to include students in special education programs, what high school graduation means for these students is not clear. We collected documentation from state departments of education to examine high school graduation requirements for students in general, and for students with disabilities. Forty-four states use Carnegie course unit requirements ranging from 10.35 to 24.00 credits. Seventeen states currently have requirements for either a minimum competency test or an exit exam. Local education agencies in several states have the option of establishing more stringent requirements than called for in state guidelines. Exit documents that are awarded to students with disabilities (e.g., standard diplomas, modified diplomas, certificates of attendance) also vary from state to state, with similar requirements sometimes earning different types of exit documents in different states. These inconsistencies in graduation requirements and their implications for students with learning disabilities are discussed. PMID- 9364899 TI - A twin study of mathematics disability. AB - Although results obtained from recent twin and adoption studies suggest that individual differences in mathematics performance are due in part to heritable influences, no genetic analysis of mathematics disability (MD) has been previously reported. In this article we present data from the first twin sample ascertained for mathematics deficits (40 identical and 23 same-sex fraternal twin pairs in which at least one member had MD). When mathematics performance data from these twin pairs were subjected to a multiple regression analysis, evidence for a significant genetic etiology was obtained. However, tests for the differential etiology of MD as a function of reading performance level were nonsignificant. Results of this first twin study of MD indicate that the condition is significantly heritable, but data from additional twin pairs will be required to test hypotheses of differential etiology more rigorously. PMID- 9364900 TI - Cognitive arithmetic and problem solving: a comparison of children with specific and general mathematics difficulties. AB - This study examined problem-solving and number-fact skills in two subgroups of third-grade children with mathematics difficulties (MD): MD-specific (n = 12) and MD-general (n = 12). The MD-specific group had difficulties in mathematics but not in reading, and the MD-general group had difficulties in reading as well as in mathematics. A comparison group of nonimpaired children (n = 24) also was included. The findings showed that on both story and number-fact problems, the MD specific group performed worse than the nonimpaired group in timed conditions but not in untimed conditions. The MD-general group, on the other hand, performed worse than the nonimpaired group, regardless of whether tasks were timed or not. An analysis of children's strategies in untimed conditions showed that both the MD-specific and the MD-general groups relied more on backup strategies than the nonimpaired group. However, children in the MD-specific group executed backup strategies more skillfully than children in the MD-general group, allowing them to achieve parity with children in the nonimpaired group when tasks were not timed. The findings suggest that children with specific MD have circumscribed deficits associated with fact retrieval, whereas children with general MD have more basic delays associated with problem conceptualization and execution of calculation procedures. PMID- 9364901 TI - Academic underachievement in ADHD subtypes. AB - Although a relationship between attention-deficit/hyperactivity disorder (ADHD) and academic underachievement has been widely reported, the nature of this relationship has not been specified. The present investigation addresses this relationship directly by comparing 24 students (20 males and 4 females) with ADHD and 20 students (15 males and 5 females) with attention-deficit disorder without hyperactivity (ADD/noH) referred to a university-based diagnostic clinic for comprehensive neuropsychological assessment. The students ranged in age from 6 years 0 months to 12 years 10 months. Consistent with previous reports, this study found that math achievement test scores for students with ADD/noH were significantly lower than those for students with ADHD. These findings support previous research suggesting the ADD/noH may represent a distinct ADD subtype. It is hypothesized that inattention interferes with students' ability to master abstract symbol systems, especially in the acquisition of basic arithmetic skills in the primary grades. PMID- 9364902 TI - The effect of five proofreading conditions on the spelling performance of college students with learning disabilities. AB - This study investigated the effect of five proofreading conditions on the spelling performance of 12 college students with learning disabilities on a composition activity. The proofreading conditions investigated were handwriting with no additional assistance, handwriting with a conventional print dictionary, handwriting with a handheld spelling checker, word processing with no additional assistance, and word processing with an integrated spelling checker. A repeated measures ANOVA was used to analyze the results, with proofreading condition used as a within-participants factor. Except for handwriting alone, all of the techniques resulted in significant reductions in the number of spelling errors in the students' written work; however, none of the techniques enabled the students to produce compositions with a mean level of spelling accuracy comparable to that of their nondisabled peers. PMID- 9364903 TI - Learning disabilities and adolescent suicide. AB - To investigate the hypothesis that learning disabilities (LD) play a part in adolescent suicide, all available suicide notes (n = 27) from 267 consecutive adolescent suicides were analyzed for spelling and handwriting errors. The suicide notes were dictated to adolescents with LD and adolescent non-LD controls. The results showed that 89% of the 27 adolescents who committed suicide had significant deficits in spelling and handwriting that were similar to those of the adolescents with LD, and they were significantly more impaired than the non-LD adolescents and older adults (65 and older) who had committed suicide in the same time period and in the same geographical area. PMID- 9364904 TI - Correspondences among parent, teacher, and student perceptions of adolescents' learning disabilities. AB - A group of 26 adolescents with learning disabilities (Grades 9 through 12), their parents, and their special education teachers were asked to rate the students' skills in each of 21 specific areas covering general ability, oral language, reading, written language, math, study skills, motivation, social skills, attention, and nonverbal skills. Correspondences in the absolute and relative ratings of parents, teachers, and students across the 21 skill areas were examined. The parents' ratings were consistent with those of the teachers in 16 areas and significantly lower than the teachers in 5 areas. The students' ratings were generally higher than those of their parents and teachers. The student teacher differences were significant in 6 areas, whereas the student-parent differences were significant in 11 areas. Although generally lower in absolute terms than the ratings of their children, the parents' relative ratings were strikingly parallel to their children's ratings across skill areas (r = 80). Differences in the reference groups used for the ratings did not seem to account for the discrepant ratings. Possible implications of the differing perceptions of students' learning disabilities for students' self-esteem and academic progress are discussed. PMID- 9364905 TI - Supported inquiry science: teaching for conceptual change in urban and suburban science classrooms. AB - Science education professionals generally agree that hands-on, inquiry-based science potentially benefits all students, yet there are few specific guidelines for helping students with learning disabilities (LD) achieve success in general education science classrooms. This study compared the effects of two approaches to hands-on science--supported inquiry science (SIS) and activity-based science- in six urban and two suburban fourth-grade general education classrooms. Participants included 172 students, 33 of whom had learning disabilities. The study found that students with and without LD demonstrated greater concept learning in the SIS classrooms, which focused on eliciting and reworking students' misconceptions and co-constructing knowledge under the guidance of a teacher-coach. PMID- 9364906 TI - Cognitive deficits in nonretarded adults with fetal alcohol syndrome. AB - Persons with fetal alcohol syndrome (FAS) who are not mentally retarded often have difficulty qualifying for special educational and vocational services. In this pilot study, 16 nonretarded young adults with FAS were divided into two groups--one with average to above-average IQ and one with borderline to low average IQ. Participants in both groups manifested clear deficits on neuropsychological measures sensitive to complex attention, verbal learning, and executive function. The frequency and severity of cognitive impairment demonstrated in both FAS groups were greater than what would have been predicted on the basis of IQ alone. The implications of these findings for identification and management of cognitive impairment in individuals with FAS are discussed. PMID- 9364907 TI - Molecular mechanisms of Nod factor diversity. AB - The rhizobia-legume symbiosis is highly specific. Major host specificity determinants are the bacterial Nod factor signals that trigger the nodulation programme in a compatible host. Nod factors are lipo-chitooligosaccharides (LCOs) varying in the oligosaccharide chain length, the nature of the fatty acids and substitutions on the oligosaccharide. The nod genotype of rhizobia, which forms the genetic basis for this structural variety, includes a set of nodulation genes encoding the enzymes that synthesize LCOs. Allelic and non-allelic variation in these genes ensures the synthesis of different LCO structures by the different rhizobia. The nod genotypes co-evolved with host plant divergence in contrast to the rhizobia, which followed a different evolution. Horizontal gene transfer probably played an important role during evolution of symbiosis. The nod genotypes are particularly well equipped for horizontal gene transfer because of their location on transmissible plasmids and/or on 'symbiosis islands', which are symbiotic regions associated with movable elements. PMID- 9364908 TI - Contribution of novel choline-binding proteins to adherence, colonization and immunogenicity of Streptococcus pneumoniae. AB - The surface of Streptococcus pneumoniae is decorated with a family of choline binding proteins (CBPs) that are non-covalently bound to the phosphorylcholine of the teichoic acid. Two examples (PspA, a protective antigen, and LytA, the major autolysin) have been well characterized. We identified additional CPBs and characterized a new CBP, CbpA, as an adhesin and a determinant of virulence. Using choline immobilized on a solid matrix, a mixture of proteins from a pspA deficient strain of pneumococcus was eluted in a choline-dependent fashion. Antisera to these proteins passively protected mice challenged in the peritoneum with a lethal dose of pneumococci. The predominant component of this mixture, CbpA, is a 75-kDa surface-exposed protein that reacts with human convalescent antisera. The deduced sequence from the corresponding gene showed a chimeric architecture with a unique N-terminal region and a C-terminal domain consisting of 10 repeated choline-binding domains nearly identical to PspA. A cbpA-deficient mutant showed a >50% reduction in adherence to cytokine-activated human cells and failed to bind to immobilized sialic acid or lacto-N-neotetraose, known pneumococcal ligands on eukaryotic cells. Carriage of this mutant in an animal model of nasopharyngeal colonization was reduced 100-fold. There was no difference between the parent strain and this mutant in an intraperitoneal model of sepsis. These data for CbpA extend the important functions of the CBP family to bacterial adherence and identify a pneumococcal vaccine candidate. PMID- 9364909 TI - Control of virulence gene expression by plant calcium in the phytopathogen Erwinia carotovora. AB - Plant calcium can modulate a particular plant-pathogen interaction and have a decisive role in disease development. Enhanced resistance to the phytopathogenic enterobacterium Erwinia carotovora, the causal agent of bacterial soft rot disease, is observed in high-calcium plants. One of the main virulence determinants of E. carotovora, the PehA endopolygalacturonase, is specifically required in the early stages of the infection. Production of PehA was found to be dependent on the calcium concentration in the bacterial environment. An increase in extracellular calcium to mM concentrations repressed pehA gene expression without reducing or even enhancing expression of other extracellular enzyme encoding genes of this pathogen. An increase in plant calcium levels could be correlated to enhanced resistance to E. carotovora infection and to an inhibition of in planta production of PehA. Ectopic expression of pehA from a calcium insensitive promoter allowed E. carotovora to overcome this calcium-induced resistance. The results imply that plant calcium can constitute an important signal molecule in plant-pathogen interaction, which acts by modulating the expression of virulence genes of the pathogen. PMID- 9364910 TI - Localization of the sporulation protein SpoIIE in Bacillus subtilis is dependent upon the cell division protein FtsZ. AB - SpollE is an integral membrane protein that governs the establishment of cell specific gene transcription during the process of sporulation in Bacillus subtilis. Synthesis of SpollE commences shortly after the onset of sporulation, after which the protein localizes at sites of potential cell division near both ends of the sporangium. We now show that, within the limits of resolution of immunofluorescence microscopy, this bipolar pattern of localization observed in early-sporulating cells was superimposable with the bipolar pattern of localization of the cell division protein FtsZ. The localization of SpollE was dependent upon FtsZ because little or no localization was observed along the length of filaments that were generated by depleting sporulating cells for the cell division protein. In contrast, SpollE and FtsZ were found to co-localize at regularly spaced intervals in filaments generated by the use of a temperature sensitive mutant of the cell division gene divlC. Finally, in cells engineered to synthesize SpollE during growth, SpollE localized at the mid-cell position, coincident with the position of FtsZ, which exhibits a medial pattern of localization in cells undergoing binary fission. These results suggest that the bipolar pattern of localization of SpollE is dictated by the sporulation-induced switch in the position of FtsZ or of other, FtsZ-associated, cell division proteins. Thus, it appears that B. subtilis has co-opted the cell division machinery as a means of localizing a cell fate determinant to the polar septum during sporulation. PMID- 9364911 TI - Assembly of the cell division protein FtsZ into ladder-like structures in the aerial hyphae of Streptomyces coelicolor. AB - In the filamentous bacterium Streptomyces coelicolor, the cell division protein FtsZ is required for the conversion of multinucleoidal aerial hyphae into chains of uninucleoidal spores, although it is not essential for viability. Using immunofluorescence microscopy, we have shown that FtsZ assembles into long, regularly spaced, ladder-like arrays in developing aerial hyphae, with an average spacing of about 1.3 microm. Within individual hyphae, ladder formation was relatively synchronous and extended for distances over 100 microm. These ladders were present only transiently, decreasing in intensity as chromosomes separated into distinct nucleoids and disappearing upon the completion of septum formation. Evidence from the overall intensity of immunofluorescence staining suggested that ladder formation was regulated in part at the level of the accumulation and degradation of FtsZ within individual aerial hyphae. Finally, FtsZ ladder formation was under developmental control in that long arrays of FtsZ rings could not be detected in certain so-called white mutants (whiG, whiH and whiB), which are blocked in spore formation. The assembly of FtsZ into ladders represents the earliest known molecular manifestation of the process of spore formation, and its discovery provides insight into the role of whi genes in the conversion of aerial hyphae into chains of spores. We have also described a novel use of a cell wall staining technique to visualize apical tip growth in vegetatively growing hyphae. PMID- 9364912 TI - Localized reversible frameshift mutation in an adhesin gene confers a phase variable adherence phenotype in mycoplasma. AB - The variable adherence-associated (Vaa) antigen of Mycoplasma hominis is an abundant surface lipoprotein adhesin that may mediate important interactions of this wall-less prokaryotic pathogen with the human host. Extensive mutational variation of Vaa size, as well as sequence and antigenic divergence, has been described previously. Using a series of clonal isolates representing an isogenic lineage of variants oscillating in Vaa expression, Vaa is further shown in this study to undergo high-frequency phase variation in expression, which correlated precisely with the ability of M. hominis to adhere to cultured human cells. Although no DNA rearrangements or sequence differences in the 5' regions flanking vaa alleles were detected between Vaa+ and Vaa variants, intragenic vaa sequences from this lineage revealed an oscillating mutation involving a single nucleotide deletion/insertion in a short tract of adenine residues near the 5' end of the mature Vaa coding sequence, which created a translational frameshift resulting in either a complete Vaa ORF or an in-frame UAG stop codon immediately downstream of the poly-A tract. Evidence for the occurrence of this high-frequency frameshift mutation in vivo was obtained from analysis of PCR-generated vaa sequences amplified from the joint synovial fluid of a patient with M. hominis-associated arthritis, which indicated that Vaa phase variation occurs during M. hominis infection in the natural host. These results identify a distinctive frameshift mutator element in the vaa gene that governs M. hominis adherence and highlight the importance of mutational alteration of primary gene products on the mycoplasma surface as a means of generating and maintaining functional diversity in the host. PMID- 9364913 TI - The Pai-associated leuX specific tRNA5(Leu) affects type 1 fimbriation in pathogenic Escherichia coli by control of FimB recombinase expression. AB - The uropathogenic Escherichia coli strain 536 (06:K15:H31) carries two large chromosomal pathogenicity islands (Pais). Both Pais are flanked by tRNA genes. Spontaneous deletion of Pai II results in truncation of the leuX tRNA5Leu gene. This tRNA is required for the expression of type 1 fimbriae (Fim) and other virulence factors. Transcription of fimA, encoding the major type 1 fimbrial subunit is controlled by an invertable DNA switch. The inversion is catalysed by two recombinases, FimB and FimE. FimB is able to turn the switch on, FimE only off. The fimB gene of strain 536 contains five TTG codons recognized by tRNA5Leu, fimE contains only two. It was proposed that turning on the fim switch requires efficient translation of FimB, in turn requiring tRNA5Leu. Strains in which the TTG codons in fimB were replaced with CTG codons at the wild-type locus were able to produce type 1 fimbriae in the absence of leuX. fimB transcription was influenced by the presence of leuX, but only slightly affected by the presence or absence of leuX codons in fimB. FimB translation was significantly higher from codon-replaced fimB genes than that of wild-type fimB genes in various strain backgrounds. The fim switch was shown to be switched off in leuX-derivatives of E. coli 536, but could be found in the on position when the codon-altered fimB gene was exchanged into the chromosome of these strains. From these data, it is apparent that tRNA5Leu is required for efficient translation of FimB, in turn, leading to type 1 fimbrial expression. PMID- 9364914 TI - Zinc(II) tolerance in Escherichia coli K-12: evidence that the zntA gene (o732) encodes a cation transport ATPase. AB - A transposon (Tn 10dCam) insertion mutant of Escherichia coli K-12 was isolated that exhibited hypersensitivity to zinc(II) and cadmium(II) and, to a lesser extent, cobalt(II) and nickel (II). The mutated gene, located between 75.5 and 76.2 min on the chromosome, is named zntA (for Zn(II) transport or tolerance). The metal-sensitive phenotype was complemented by a genomic DNA clone mapping at 3677.90-3684.60 kb on the physical map. Insertion of a kanamycin resistance (KnR) cassette at a SalI site in a subcloned fragment generated a plasmid that partially complemented the zinc(II)-sensitive phenotype. DNA sequence analysis revealed that the KnR cassette was located within the putative promoter region of an ORF (o732 or yhhO) predicted to encode a protein of 732 amino acids, similar to cation transport P-type ATPases in the Cpx-type family. Inverse PCR and sequence analysis revealed that the Tn 10dCam element was located within o732 in the genome of the zinc(II)-sensitive mutant. The zntA mutant had elevated amounts of intracellular and cell surface-bound Zn(II), consistent with the view that zntA+ encodes a zinc(II) efflux protein. Exposure of the zntA mutant to cobalt(II) and cadmium(II) also resulted in elevated levels of intracellular and cell surface-bound metal ions. PMID- 9364915 TI - A peptidoglycan hydrolase similar to bacteriophage endolysins acts as an autolysin in Neisseria gonorrhoeae. AB - We have identified a gene encoding an autolysin (atlA) from Neisseria gonorrhoeae. The deduced amino acid sequence of AtlA shows significant similarity to the peptidoglycan degrading transglycosylases (endolysins) of bacteriophages lambda and P2, suggesting that the encoded protein also functions in peptidoglycan hydrolysis. An atlA mutant was identical to the wild-type strain in exponential growth rate, but demonstrated reduced lysis and peptidoglycan turnover in the stationary phase of growth. When transferred into a buffer solution, at a pH non-permissive for other gonococcal autolysins, an autolytic activity was detectable in the wild-type strain that was not present in the mutant. The most dramatic phenotype of the mutant occurred after extended time in stationary phase. After approximately 16h in stationary phase, both strains underwent an apparent replication event, after which the wild-type strain died rapidly whereas the atlA mutant survived considerably longer. Even after both the wild-type and mutant cells were dead, many of the mutant cells maintained intact morphology, whereas the wild-type cells were lysed. These results suggest that AtlA is a peptidoglycan transglycosylase related to bacteriophage endolysins and acts as an autolysin in the stationary phase. PMID- 9364916 TI - A secreted effector protein of Salmonella dublin is translocated into eukaryotic cells and mediates inflammation and fluid secretion in infected ileal mucosa. AB - Enteritis induced by non-typhoid pathogenic Salmonella is characterized by fluid secretion and inflammatory responses in the infected ileum. The inflammatory response provoked by Salmonella initially consists largely of a neutrophil (PMN) migration into the intestinal mucosa and the gut lumen. The interactions between Salmonella and intestinal epithelial cells are known to play an essential role in inducing the inflammatory response. Upon interaction with epithelial cells salmonellae are able to elicit transepithelial signalling to neutrophils. This signalling is recognized as a key virulence feature underlying Salmonella-induced enteritis. However, the nature and mechanism of such signalling has not been clarified to date. Here, we characterize SopB, a novel secreted effector protein of Salmonella dublin, and present data implying that SopB is translocated into eukaryotic cells via a sip-dependent pathway to promote fluid secretion and inflammatory responses in the infected ileum. PMID- 9364917 TI - Positive control of the two-component RcsC/B signal transduction network by DjlA: a member of the DnaJ family of molecular chaperones in Escherichia coli. AB - The membrane-anchored DjIA protein represents the third member of the DnaJ 'J domain' family of Escherichia coli that includes DnaJ and CbpA. DjIA possesses a J-domain at its extreme C-terminus but shares no additional homology with DnaJ. Our genetic analysis suggests that DjIA acts in concert with the RcsB/C two component signal transduction system to augment induction of the cps (capsular polysaccharide) operon and synthesis of colanic acid mucoid capsule. The DjIA J domain is essential for the observed stimulation of this pathway as deletion, or introduction of the mutation H233Q, within the highly conserved HPD tripeptide abolished all inducing activity. Deletion of the transmembrane anchor sequence also abolished all inducing activity. djIA is not an essential gene under all conditions tested, nor is it essential for mucoid capsule biosynthesis; however, strong overexpression leads to rapid loss of cell viability suggesting that the gene is normally tightly regulated. Northern analysis revealed that djIA message was extremely unstable but could be induced or stabilized in response to cold shock. The activation of the cps operon by DjIA is dependent upon both DnaK(Hsp70) and GrpE, and therefore we propose a role for DjIA, together with this chaperone machine, as a novel regulator of a two-component histidine kinase signal transduction pathway. PMID- 9364919 TI - Direct evidence for active segregation of oriC regions of the Bacillus subtilis chromosome and co-localization with the SpoOJ partitioning protein. AB - We have developed methods for labelling regions of the Bacillus subtilis chromosome with the nucleotide analogue 5-bromodeoxyuridine (BrdU) and for subcellular visualization of the labelled DNA. Examination of oriC-labelled chromosomes in outgrowing spores has provided direct evidence for active segregation of sister chromosomes. Co-immunodetection of Spo0J and BrdU-labelled DNA has directly confirmed the expected close association between this chromosome partitioning protein and the oriC region of the chromosome. The results provide further support for the notion that bacterial cells use an active mitotic-like mechanism to segregate their chromosomes. PMID- 9364918 TI - Point mutations in the transmembrane domain of DjlA, a membrane-linked DnaJ-like protein, abolish its function in promoting colanic acid production via the Rcs signal transduction pathway. AB - DjIA is a novel DnaJ-like protein localized to the inner membrane of Escherichia coli through the single transmembrane domain (TMD) found at the N-terminus. The overproduction of DjIA activates expression of the cps operon, controlling synthesis and export of the extracellular polysaccharide colanic acid via the Rcs/B two-component signal transduction pathway. We now show that both the TMD and the J-region are essential for the induction of cps expression observed with the overproduction of DjIA. Furthermore, we describe the isolation and characterization of different point mutations in the TMD that completely or partially block the induction of cps expression associated with overproduction of DjIA. These mutations were shown not to affect the localization, stability or topology of the mutant DjIA proteins. We propose that these mutations are affecting specific interactions between the TMD of DjIA and its substrate protein(s), for example RcsC, the membrane sensor kinase partner of the Rcs/B signal transduction pathway. PMID- 9364920 TI - Assembly and interactions of cotJ-encoded proteins, constituents of the inner layers of the Bacillus subtilis spore coat. AB - During Bacillus subtilis endospore formation, a complex protein coat is assembled around the maturing spore. The coat is made up of more than two dozen proteins that form an outer layer, which provides chemical resistance, and an inner layer, which may play a role in the activation of germination. A third, amorphous layer of the coat occupies the space between the inner coat and the cortex, and is referred to as the undercoat. Although several coat proteins have been characterized, little is known about their interactions during assembly of the coat. We show here that at least two open reading frames of the cotJ operon (cotJA and cotJC) encode spore coat proteins. We suggest that CotJC is a component of the undercoat, since we found that its assembly onto the forespore is not prevented by mutations that block both inner and outer coat assembly, and because CotJC is more accessible to antibody staining in spores lacking both of these coat layers. Assembly of CotJC into the coat is dependent upon expression of cotJA. Conversely, CotJA is not detected in the coats of a cotJC insertional mutant. Co-immunoprecipitation was used to demonstrate the formation of complexes containing CotJA and CotJC 6 h after the onset of sporulation. Experiments with the yeast two-hybrid system indicate that CotJC may interact with itself and with CotJA. We suggest that interaction of CotJA with CotJC is required for the assembly of both CotJA and CotJC into the spore coat. PMID- 9364922 TI - Characterization of a ferric-binding protein mutant in Haemophilus influenzae. AB - Ferric-binding proteins (FbpA) have been implicated in the transferrin receptor mediated iron acquisition pathways of Haemophilus influenzae and Neisseria spp. These proteins are believed to function by shuttling iron from outer membrane transferrin receptors to a specific inner membrane permease complex. However, the role of these proteins has not been conclusively resolved, as attempts at creating isogenic mutants in the fbpA genes of both species have been unsuccessful, prompting the hypothesis that FbpA may play a critical role in H. influenzae and Neisseria spp. This study describes the construction and characterization of an H. influenzae isogenic fbpA mutant. It is demonstrated that this mutant is deficient in its ability to use human transferrin as a sole iron source, even though the strain is still competent for binding human transferrin. It is also demonstrated that this mutant is impaired in its ability to use ferric citrate as an iron source, and grows at a reduced rate relative to wild type in broth supplemented with protoporphyrin rather than haemin. PMID- 9364921 TI - Mutational analysis of the RecA protein L1 region identifies this area as a probable part of the co-protease substrate binding site. AB - Previous mutational analysis of the L1 region of the RecA protein suggested that Gly-157 and Glu-158 are 'hot-spots' for the occurrence of constitutive LexA co protease mutants (coprt[c]). In the present study, we clearly establish that position 157 is a hot-spot for the occurrence of such mutants, as 12 of 14 and 10 of 14 substitutions result in this phenotype for UmuD and LexA cleavage respectively. The frequency of such mutations at position 158 is somewhat lower, 8 of 13 and 5 of 13 for UmuD and LexA respectively. Comparison of the UmuD vs. LexA co-protease activity for all single mutants with substitutions at positions 154, 155, 156, 157 and 158 (47 in total) reveals that, although there is good agreement among most mutants regarding their ability to cleave both LexA and UmuD, there are two in particular (Glu-154-->Asp and Glu-154-->Gln) that show a clear preference for cleavage of UmuD. We also show that three second-site mutations that completely suppress coprt(c) activity toward LexA have little or no effect on the coprt(c) activity of the primary mutant toward UmuD. In addition, we observe a high frequency of second-site suppressor mutations, suggesting a functional interaction among side-chains in this region. Together, these results support the idea that the L1 region of RecA makes up part of the co protease substrate-binding site. PMID- 9364923 TI - Identification and characterization of an aliphatic amidase in Helicobacter pylori. AB - We report, for the first time, the presence in Helicobacter pylori of an aliphatic amidase that, like urease, contributes to ammonia production. Aliphatic amidases are cytoplasmic acylamide amidohydrolases (EC 3.5.1.4) hydrolysing short chain aliphatic amides to produce ammonia and the corresponding organic acid. The finding of an aliphatic amidase in H. pylori was unexpected as this enzyme has only previously been described in bacteria of environmental (soil or water) origin. The H. pylori amidase gene amiE (1017 bp) was sequenced, and the deduced amino acid sequence of AmiE (37746Da) is very similar (75% identity) to the other two sequenced aliphatic amidases, one from Pseudomonas aeruginosa and one from Rhodococcus sp. R312. Amidase activity was measured as the release of ammonia by sonicated crude extracts from H. pylori strains and from recombinant Escherichia coli strains overproducing the H. pylori amidase. The substrate specificity was analysed with crude extracts from H. pylori cells grown in vitro; the best substrates were propionamide, acrylamide and acetamide. Polymerase chain reaction (PCR) amplification of an internal amiE sequence was obtained with each of 45 different H. pylori clinical isolates, suggesting that amidase is common to all H. pylori strains. A H. pylori mutant (N6-836) carrying an interrupted amiE gene was constructed by allelic exchange. No amidase activity could be detected in N6 836. In a N6-urease negative mutant, amidase activity was two- to threefold higher than in the parental strain N6. Crude extracts of strain N6 slowly hydrolysed formamide. This activity was affected in neither the amidase negative strain (N6-836) nor a double mutant strain deficient in both amidase and urease activities, suggesting the presence of an independent discrete formamidase in H. pylori. The existence of an aliphatic amidase, a correlation between the urease and amidase activities and the possible presence of a formamidase indicates that H. pylori has a large range of possibilities for intracellular ammonia production. PMID- 9364924 TI - Nuclear RNA accumulations contain released transcripts and exhibit specific distributions with respect to Sm antigen foci. AB - RNA polymerase II transcripts accumulate within mammalian nuclei at distinct sites and exhibit varying morphology. Certain RNA species are organized in elongated structures, whereas others appear as dot-like concentrations. To analyze the status of the RNA within these accumulations, we investigated the composition of accumulations derived from Epstein-Barr virus (EBV) genes, human papilloma virus 18 (HPV18) open reading frames E6 and E7, as well as heat shock protein 89a (hsp89alpha) and 89beta (hsp89beta) genes. No differential distribution of exon and intron sequences within concentrations of EBV RNA could be observed. Whereas accumulations of hsp89alpha and hsp89beta always coincided with Sm antigen foci, the RNA of EBV and HPV18 never co-localized with these foci. This excludes Sm antigen foci as the only sites of splicing and suggests gene-specific variation in the nuclear localization of transcripts. Two sets of experiments were performed to assess whether transcripts in the RNA accumulations are in statu nascendi or products released from a discrete gene locus. Because RNA transcripts derived from EBV genes, which are located on both ends of the genome, were all distributed along the entire length of the RNA signals, they cannot be derived from a highly decondensed genomic DNA extending throughout elongated RNA accumulations. Furthermore, removal of labeled RNA sequences and subsequent visualization of DNA confirmed the confinement of the genomic sequences to a small subregion of the area occupied by accumulated RNA. Therefore, this study supports the view of RNA accumulations as a stream of molecules that delineate a path from a dot-like gene locus toward the nuclear envelope for export into the cytoplasm. PMID- 9364926 TI - Relationship of repair and replicative DNA synthesis to cell cycle in Chinese hamster ovary (CHO-K1) cells. AB - To strengthen the causal association between repair and replicative DNA synthesis, we have simultaneously measured the two types of DNA synthesis in a cell cycle-dependent manner. Synchrony was obtained by counterflow centrifugal elutriation of logarithmic-phase Chinese hamster ovary (CHO) cells kept in suspension cultures. A comparison of cell cycle profiles of ATP-dependent replicative and ATP-independent repair synthesis in permeable cells shows opposite trends. The rates of repair synthesis and replication are inversely correlated. PMID- 9364925 TI - Chromosomal localization, structure, and regulation of the UGT2B17 gene, encoding a C19 steroid metabolizing enzyme. AB - UGT2B17 is a UDP-glucuronosyltransferase enzyme expressed in several extrahepatic steroid target tissues, including the human prostate, where it glucuronidates C19 steroids such as dihydrotestosterone (DHT), androsterone (ADT), and androstane 3alpha, 17beta-diol (3alpha-diol). To determine if UGT2B17 is regulated by physiological effectors of the human prostate, DHT and epidermal growth factor (EGF) were demonstrated to specifically down-regulate the steady-state levels of UGT2B17 transcript and protein in LNCaP cells (Guillemette et al., 1997). These results implicate regulation of UGT2B17 at the level of gene transcription, therefore, a P-1-derived artificial chromosome (PAC) clone of 120 kb containing the entire UGT2B17 gene was isolated. The gene is comprised of six exons spanning approximately 30 kb, and fluorescence in situ hybridization of the UGT2B17 PAC clone to normal human lymphocyte chromosomes, mapped the gene to chromosome 4q13. To determine if the 5'-flanking DNA of the UGT2B17 gene is sufficient to confer gene expression, a 2,942-bp fragment was subcloned into a luciferase reporter plasmid and yielded an activity of 25-fold over background when transfected in LNCaP cells. However, transfection of the construct into HK-293, MCF-7, JEG-3, and HepG2 cells yielded only a moderate activity of two- to five-fold over background. Treatment of transfected LNCaP cells with 10 nM R1881, a nonmetabolizable analog of DHT, and 10 ng/ml EGF decreased the luciferase activity by 60%. This suggests that at least part, if not all, of the inhibitory effect of EGF and DHT on UGT2B17 is at the level of transcription. Progressive 5' deletions of the UGT2B17 5'-flanking region in the luciferase constructs alleviated the inhibition by R1881 and EGF, and revealed several potential responsive elements that may confer the observed regulation of the UGT2B17 gene. This study demonstrates regulation of the UGT2B17 gene by physiological effectors of the human prostate and supports the hypothesis that UGT enzymes are involved in steroid metabolism in extrahepatic tissues. PMID- 9364927 TI - The Srp40 protein plays a dose-sensitive role in preribosome assembly or transport and depends on its carboxy-terminal domain for proper localization to the yeast nucleoskeleton. AB - The yeast SRP40 gene product (Srp40p) is a highly serine-rich protein organized in three distinct domains. The roles of these domains in localizing Srp40p were determined. By indirect immunofluorescence microscopy, Srp40p localizes to punctate, sometimes fibrillar, subnuclear structures that might include the nucleolus. Its amino-terminal and medial domains are similar. They each start with a short basic stretch containing a nuclear localization signal, followed by a long acidic stretch with 76% serines; such acidic stretches are thought to mediate binding to ribosomal proteins in the nucleolus. Either domain is sufficient to determine nuclear localization of Srp40p. The Srp40p carboxy terminal domain shows significant homology to the cognate domain of Nopp140, a mammalian nucleolar phosphoprotein of 140 kD. The carboxy-terminal domain alone, or fused to a reporter protein, displays a punctate localization outside the nucleus. Srp40p and Nopp140 share a highly homologous 39-residue motif within their similar carboxy-terminal domains. Inside or outside the nucleus, this motif is important to prevent Srp40p diffusion or degradation. These observations suggest that the punctate immunoreactive structure is nucleoskeletal and might result from Srp40p self-assembly. SRP40 genetically interacts with four mutants affected in stable RNA synthesis and one mutant blocked in protein translocation to the endoplasmic reticulum. Growth defects, but no translocation or rRNA transcription/maturation phenotypes, were observed upon SRP40 inactivation or strong overexpression. Together, these data point to a dispensable, dosage sensitive, role of Srp40p in preribosome assembly or transport. PMID- 9364929 TI - Feline mucopolysaccharidosis type VI: correction of glycosaminoglycan storage in myoblasts by retrovirus-mediated transfer of the feline N-acetylgalactosamine 4 sulfatase gene. AB - Mucopolysaccharidosis type VI (MPS VI) is an autosomal recessive lysosomal storage disorder characterised by the deficiency of N-acetylgalactosamine 4 sulfatase (4S). MPS VI has also been described in the cat. As an initial step toward muscle-mediated gene therapy in the MPS VI cat, we have made two retroviral constructs (pLf4S and pLf4SSN) that transduce the feline 4S gene. Both constructs were designed to express the feline 4S sequence from the viral long terminal repeat promoter. In addition pLf4SSN expressed the neomycin resistance gene from the SV40 early promoter. Amphotrophic virus was produced for each construct and used to transduce feline MPS VI myoblasts. Lf4S- and Lf4SSN transduced MPS VI feline myoblasts demonstrated correction of glycosaminoglycan storage and contained 55-fold and 3.5-fold elevated levels of 4S activity when compared with normal feline myoblasts respectively. Recombinant feline 4S (rf4S) secreted by Lf4S-transduced MPS VI myoblasts was shown to be endocytosed by MPS VI feline cells via the mannose-6-phosphate receptor system, leading to metabolic correction. The results from this study demonstrate that muscle-mediated gene replacement therapy may be a viable method for achieving circulating levels of recombinant f4S (rf4S) in the MPS VI cat. PMID- 9364928 TI - Convertase PC2 and the neuroendocrine polypeptide 7B2 are co-induced and processed during neuronal differentiation of P19 embryonal carcinoma cells. AB - Convertases of the subtilisin/kexin family are responsible for the biological activation of a variety of pro-proteins, pro-hormones, and pro-trophic factors, and thus can modulate various aspects of embryonic development. We investigated the expression of each convertase by Northern hybridization during cell differentiation in vitro, using the mouse embryonal carcinoma cell line P19 as a model. The neuroendocrine convertase PC2 and 7B2, its specific binding protein, are co-induced during neuronal differentiation of P19 cells with retinoic acid, whereas the other convertases are not or follow different patterns of temporal expression. The mature forms of PC2 and 7B2 proteins are detected together by immunoblotting following induction of mRNA expression, indicating that these proteins are processed early during brain development. These results demonstrate that PC2 and 7B2 gene expression and protein processing are in a close temporal association during neuronal differentiation and point to the value of the P19 cell model to study the significance and the regulation of this relationship in mammalian brain development. PMID- 9364930 TI - Expression and characterization of a novel UDP-glucuronosyltransferase, UGT2B9, from cynomolgus monkey. AB - Uridine diphosphate glucuronosyltransferases (UGTs) are important phase II detoxification enzymes. Despite the expression of UGT proteins in many species, previous results have suggested that simians represent the most appropriate animal model to study the glucuronidation of steroids in extrahepatic steroid target tissues. Northern blot analysis using a pool of human UGT2B cDNA probes demonstrated the expression of homologous UGT2B transcripts in several tissues including the liver, kidney, adrenal, breast, testis, and prostate of the cynomolgus monkey (Macacafascicularis). Western blot analyses using a polyclonal antibody raised against human UGT2B17 protein also demonstrated expression of homologous UGT2B proteins in monkey tissues. cDNA libraries were constructed from monkey liver and prostate mRNA and a novel UGT2B cDNA, UGT2B9, was isolated from both libraries. The UGT2B cDNA from the prostate library is 2,648 bp in length and contains an open reading frame of 1,587 bp encoding a protein of 529 residues. In vitro transcription/translation of the cDNA clone produced a protein of 52 kD. The UGT2B9 cDNA clone was transfected into HK293 cells and a stable cell line expressing UGT2B9 protein was established. The activity of UGT2B9 was tested with over 60 compounds and was demonstrated to be active on C18, C19, and C21 steroids, bile acids, and several xenobiotics including eugenol, 1-naphthol, and p-nitrophenol. Kinetic analysis revealed that UGT2B9 glucuronidates steroids with high affinity and efficiency with Km values of 0.2, 3.2, 0.2, and 1.8 microM for dihydrotestosterone, testosterone, androsterone, and 1,3,5,10-estratrien-3,4 diol-17-one, respectively. It is apparent that this simian UGT2B enzyme is specific for more different classes of steroids than any other UGT enzyme characterized to date, and may be related to the high plasma levels of glucuronidated C19 steroids found in the cynomolgus monkey. PMID- 9364931 TI - Enhancement of the transcription potential of nascent chromatin by chromosomal proteins HMG-14/-17 is coupled to nucleosome assembly and not DNA synthesis. AB - We have previously demonstrated that in Xenopus egg extracts, which support DNA strand synthesis and chromatin assembly, incorporation of chromosomal proteins HMG-14/-17 into nascent nucleosomes increases the transcriptional potential of a chromatin template carrying the Xenopus 5S RNA gene. Here we use the single stranded and double-stranded forms of a plasmid carrying a 5S RNA maxigene, to test whether the effect of HMG-14/-17 on transcription requires DNA synthesis and whether these proteins will affect transcription through a region containing nucleosomes. We find that most of the transcripts were about 350 nucleotides long, suggesting that HMG-14/-17 enhance transcription through a region that could contain nucleosomes. HMG-14/-17 enhance transcription of chromatin templates assembled onto double-stranded DNA, in the absence of DNA synthesis. Single-round transcription assays suggest that HMG-14/-17 increase transcription from templates assembled onto both single- and double-stranded DNA by increasing the specific activity, and not the number, of transcriptionally active templates. We conclude that the effect of HMG-14/-17 on the transcriptional potential of chromatin is linked to nucleosome assembly and is not linked to DNA synthesis. PMID- 9364932 TI - H-ras oncogene activation in invasive UVR-induced corneal sarcomas of the opossum Monodelphis domestica. AB - Chronic exposure to ultraviolet radiation (UVR) induces corneal sarcomas in the South American opossum Monodelphis domestica. Cell lines are readily established from these tumors. Northern blotting of mRNA from six such cell lines revealed high expression of the H-ras oncogene. H-ras cDNA from an eye tumor cell line was cloned and characterized; the germline sequence of codons 12, 13, and 61 was confirmed by examination of H-ras sequences amplified from liver DNA by the polymerase chain reaction. The Monodelphis H-ras coding sequence is 84-89% identical to that of other vertebrates at the nucleotide level, and the predicted 189-amino-acid sequence differs by 2-12 amino acids from that of other vertebrates. Analysis of 12 primary invasive corneal sarcomas induced by chronic UVR exposure revealed no evidence of H-ras gene amplification or rearrangement. One tumor was heterozygous for an activating point mutation in codon 61 of the H ras gene; the tumor was also homozygous for a point mutation at an adjacent site in codon 62. These results provide additional evidence for the functional importance and consequent evolutionary conservation of the ras oncogenes. PMID- 9364933 TI - Analysis of 36-kilodalton protein (PapA) associated with the bacteriophage particle of Bartonella henselae. AB - A library of Bartonella henselae DNA was screened with antibody raised to the bacteriophage particle associated with this organism. A clone was isolated that expresses a 36-kD protein (termed PapA for particle-associated protein) when examined by immunoblot analysis using antibody raised to the particle. Southern blot hybridization indicates that the gene is present on the bacterial chromosome and packaged into the 14-kb particle-associated DNA. A papA-specific probe hybridized to multiple bands of B. henselae genomic DNA digested with several different restriction endonucleases. Thus, the gene is present in multiple copies on the genome or in different arrangements within a given population of B. henselae cells. The gene coding for PapA has been sequenced and codes for a 326 amino-acid protein with a deduced molecular weight of 36,161 daltons. The deduced protein shows 33.3% identity over a 108-amino-acid sequence with the P-min gene product of Escherichia coli. P-min is partially located within the invertible P region of the excisable element e14, found on the E. coli chromosome. Taken together, these results suggest that papA is present on a mobile genetic element of the B. henselae genome and is also packaged into the bacteriophage particle. PMID- 9364934 TI - Intratumoral heterogeneity for hsp90beta mRNA levels in a breast cancer cell line. AB - BC-3A and BC-61 are two breast cancer cell lines that have been cloned from parental 8701-BC cells and exhibit different biosynthetic, proliferative, and invasive properties in vitro. In the attempt to search whether alterations in the profiles of gene expression could be detected, we have submitted both cytotypes to identification of differentially expressed cDNAs. In addition, steroid hormone receptor mRNA arrays and in vivo tumorigenesis of the two lines have been checked. The technique used allowed identification of changes in the expression of the 90-kD heat shock protein-beta (hsp90beta) which is prominently down regulated in BC-61 cells. Because we have also found that these cells, which lack estrogen receptor mRNA synthesis, display a more invasive behavior in vitro and increased tumorigenesis in vivo, we propose that evaluation of hsp903 transcript levels may be taken into consideration for screening as a novel molecular marker of breast cancer progression. PMID- 9364935 TI - Alterations in the chromatin structure of the distal promoter region of the bovine oxytocin gene correlate with ovarian expression. AB - The mechanisms regulating the expression of the neuropeptide hormone gene oxytocin have not yet been elucidated in detail. The binding of the orphan receptor Ad4BP, the bovine homolog of steroidogenic factor-1 (SF-1), which is correlated with in vivo oxytocin transcription in the luteinizing granulosa cells of the bovine corpus luteum, is not sufficient to explain the transcriptional up regulation in these cells. Therefore, we started experiments to identify other regions of the oxytocin locus that are involved in gene activation. The study presented here is the very first investigation of DNA methylation and chromatin structure in the distal promoter region of the bovine oxytocin gene. We show that this region is tissue-specifically hypomethylated in bovine granulosa cells. Upon stimulation of the cells with the adenylate cyclase-activator forskolin, a DNase I-hypersensitive site is induced in the distal promoter region. Additionally, we find binding of a monomeric nuclear orphan receptor directly within the region of inducible DNase I sensitivity; this factor is not identical to Ad4BP/SF-1. This study identifies a region in the bovine oxytocin distal promoter where tissue specific changes in DNA methylation and chromatin structure correlate with high induction of oxytocin gene transcription, and suggests that the binding of transcription factors to this region may be important for the up-regulation of oxytocin gene expression. PMID- 9364936 TI - Cloning, expression, and chromosomal mapping of a novel human CC-chemokine receptor (CCR10) that displays high-affinity binding for MCP-1 and MCP-3. AB - Chemokines mediate their chemotactic, proinflammatory effects by binding to and activating a variety of specific receptors belonging to the G protein-coupled superfamily of seven-transmembrane serpentine receptors. We report the cloning, chromosomal localization, expression, and ligand binding of a novel CC chemokine receptor, CCR10. CCR10 is expressed primarily in placenta and fetal liver, and binds two of the CC chemokines, monocyte chemoattractant protein (MCP)-1 and MCP 3, with highest affinity. The KD for MCP-3 binding was 1 nM, and MCP-1 competed for MCP-3 binding with an IC50 of 1.2 nM. The CC chemokines MCP-4 and RANTES competed for MCP-3 binding with IC50 values of 7.5 and 5.4 nM, respectively. The chromosomal location of CCR10 was determined to coincide with the CC chemokine receptor cluster on chromosome 3 (3p21.31-3p21.32). These results indicate that CCR10 is a novel CC chemokine receptor with a unique expression pattern that would be consistent with a role in placental immunity or hematopoiesis. PMID- 9364937 TI - Specific induction of the hsr omega locus of Drosophila melanogaster by amides. AB - We report here that 3-aminobenzamide and other amides, such as formamide, acetamide and nicotinamide, specifically induce a high rate of transcription at the 93D puff (the hsr omega heat shock gene) in polytene chromosomes of Drosophila melanogaster. Other chemicals, such as benzamide, colchicine, thiamphenicol and paracetamol, that are already known to specifically induce transcription at the hsr omega locus are also identified as amides. In view of the specific induction of the 93D puff by different amides and other data that demonstrate hsr omega transcription in response to benzamide and colchicine etc. to be independent of its heat shock induction, it appears likely that amides induce this locus through distinct regulatory elements that we propose to designate amide response elements (AREs). PMID- 9364938 TI - The STR120 satellite DNA of soybean: organization, evolution and chromosomal specificity. AB - A highly repeated DNA sequence family, STR120, with tandemly arranged repetitive units (monomers) of approximately 120bp, has been identified in soybean [Glycine max (L.) Merr.]. Five related clones showing tandem repeats of a 120-bp-long monomer were isolated from a soybean genomic library. Results of Southern blotting experiments using three of the clones as probes onto genomic DNA digested with different restriction enzymes were in agreement with a tandem arrangement of these sequences in the genome. A total of 12 monomers were sequenced, showing considerable sequence heterogeneity. A consensus sequence of 126 bp was obtained that exhibits an average similarity of 81% to the sequenced units. In three of the clones identified, neighbouring units are significantly more similar to each other than to units from different clones; in the remaining two clones, however, similarity between the two units observed is low (70%), while the overall similarity between the two clones is high (95%). This indicates that in these cases the repetitive unit may be the dimer rather than the monomer. Based on the presence of direct repeats within each monomer, we suggest that the 120-bp monomer may itself have evolved by duplication of an ancestral 60-bp unit. The STR120 family distribution is limited to annual soybeans and is not found, at least at high-copy number, in related perennial soybeans or other members of the tribe Phaseolae. Fluorescence in situ hybridization (FISH) to metaphase chromosomes using four of the clones as probes shows that the number of chromosomal locations differs depending on the stringency conditions and goes from two to eight when the stringency is progressively lowered. The estimated copy number for one of the clones is from 5000 to 10000, but this may just represent a lower boundary for the whole family in consideration of the high sequence divergence observed within the family. FISH and sequence analysis therefore indicate that different subfamilies as well as higher-order repeat units are present in the STR120 family, very much like those in primate alpha satellite DNA, and that some of the subfamilies seem to exhibit divergence on a chromosomal basis. PMID- 9364939 TI - Physical relationship between satellite I and II DNA in centromeric regions of sheep chromosomes. AB - Fluorescence in situ hybridization (FISH) with probes representing sheep satellite I and satellite II DNAs shows a different distribution of the two repetitive DNA families in the centromeric region of most chromosomes. The single signal per chromosome produced by the satellite I probe suggests close proximity of this DNA family to the primary constriction. Satellite II produces two separate signals on the sister chromatids, and large blocks of satellite II DNA constitute most of the short arm of all acrocentric chromosomes. We have isolated and sequenced a phage clone containing a junction between discrete blocks of satellite I and satellite II sequences. The junction is characterized by an abrupt juxtaposition of arrays of the two satellites. The possibility that the peculiar structural features of this junction could have a functional significance is discussed. PMID- 9364940 TI - Cell cycle changes in A-type lamin associations detected in human dermal fibroblasts using monoclonal antibodies. AB - A new panel of anti-A-type lamin monoclonal antibodies was generated. Epitope mapping was performed by immunoblotting against GST-lamin fusion peptides. Epitopes were mapped to four different regions of human lamin A and three different regions of human lamin C. The distribution of A-type lamins was compared with the distribution of the proliferation marker Ki67 in proliferating and quiescent cultures of human dermal fibroblasts (HDFs) using a double indirect immunofluorescence assay. Antibodies that had been mapped to a region of the lamin C tail stained the nuclear envelope of proliferating and quiescent cells equally brightly. In contrast, antibodies recognizing epitopes in the head domain and rod domain of lamins A and C and the tail domain of lamin A stained the nuclear envelope of quiescent cells strongly but reacted poorly or not at all with the nuclear envelope of proliferating cells. Changes in the level of expression of lamins A and C were not detected in immunoblotting assays. However, epitope masking was revealed, and this occurred by two distinct mechanisms. Epitope masking in the head domain of lamins A and C occurred as a result of protein phosphorylation. Epitope masking in the rod domain of lamins A and C and in the tail domain of lamin A occurred through a physical association between the lamin and chromatin and/or other nuclear proteins. The cell cycle timing of epitope masking was investigated in HDFs that had been restimulated after serum starvation. Extensive epitope masking in restimulated cells only occurred after cells had passed through mitosis. These results are consistent with the hypothesis that rearrangement of A-type lamin filaments, as cells progress from a quiescent to a proliferating state, results in altered lamina associations. PMID- 9364941 TI - The distribution of binding sites for centromere protein B (CENP-B) is partly conserved among diverged higher order repeating units of human chromosome 6 specific alphoid DNA. AB - We previously reported the isolation of alphoid satellite clones from a human genomic library using a DNA immunoprecipitation with centromere protein B (CENP B). Here, we have characterized the distribution of CENP-B-binding sites on the 3 kb BamHI repeats of the cos2 clone. Using in situ hybridization, this alphoid satellite was located primarily at the centromeric region of chromosome 6. The functional binding sites were mapped by precipitating the restriction fragments with recombinant CENP-B in vitro. One repeat (2B3-11) consisted of 19 copies of alphoid monomer, eight of which possessed the binding sites, while another (2B3 9) consisted of 18 copies of the monomer, seven of which possessed the binding sites. The distribution of the sites was well conserved between them, except for the terminus. A similar analysis with the remaining 6-kb region suggested the presence of a continuous 1-kb region with regular spacing of EcoRI sites and the CENP-B-binding sites. When the nucleotide sequence of 2B3-11 was compared with that of another chromosome 6-specific alphoid repeat (p308) that had been described previously, this 1-kb region was highly conserved between them. The distribution of the CENP-B binding sites and the order of alphoid monomers might define the folding of alphoid repeats in the centromeric region. PMID- 9364942 TI - High heterochromatin content in somatic chromosomes of two unrelated species of Diplopoda (Myriapoda). AB - For the first time, a conventional analysis of C-banded karyotypes was carried out in two distantly related diplopod species; this revealed an impressive percentage of heterochromatin in both genomes. In Acanthopetalum sicanum (Order Callipodida) (2n = 12), heterochromatin constitutes about 60% of the total DNA in females and 56% in males, whereas in Enologus oxypygum (Order Julida) (2n = 22) it is about 67% in both sexes. Heterochromatin of the two species was found to be similar in base composition (AT rich) and heterochromatin distribution, indicating that it has accumulated in a species-specific manner. Sex-determining mechanisms of the XY type were detected in both A. sicanum and E. oxypygum. In A. sicanum, the Y presented the lowest heterochromatic content of all chromosomes in the karyotype, whereas the X presented the highest. PMID- 9364943 TI - Male-biased distribution of the human Y chromosomal genes SRY and ZFY in the lizard Calotes versicolor, which lacks sex chromosomes and temperature-dependent sex determination. AB - In the present investigation on the lizard Calotes versicolor, which lacks temperature-dependent sex determination, all the conventional cytological techniques used failed to resolve a distinguishable pair of sex chromosomes. However, probing of the genome with the human Y-linked genes SRY and ZFY showed sex-specific bias in their distribution. While the SRY probe hybridized to all the males, more than half of the females examined did not show any hybridization. ZFY hybridized to both the sexes, giving two bands; one was common to all the individuals of both sexes, but the other, of the lower molecular length, occurred in all the males but in less than 50% of females. This predominantly male specific band is named AMF. The SRY-positive females were also positive for the AMF of ZFY. As positive as well as negative females were fertile and none of the males lacked SRY, it appears that SRY is essential for males only and that both the genes are syntenic in this species. This report raises interesting possibilities on the differentiation of the sex chromosomes in C. versicolor and evolution of SRY/ZFY on the Y chromosome of eutherian mammals through the ancestral group(s) that harbour sex-independent SRY- and ZFY-related genes. PMID- 9364944 TI - Extreme axial equalization and wide distribution of recombination nodules in the primitive ZW pair of Rhea americana (Aves, Ratitae). AB - Pachytene oocytes from the ratite bird Rhea americana were used for synaptonemal complex analysis with a surface spreading technique and phosphotungstic acid staining. The ZW bivalent is slightly smaller than the fourth autosomal bivalent and clearly shows unequal W and Z axes only in 27% of the bivalents. Most of the ZW pairs are completely adjusted and thus the W and Z axes are almost equal in length. A sample of 134 recombination nodules (RNs) from 63 ZW pairs showed a striking departure of number and location of these nodules compared with those of carinate birds. The average number of RNs in the ZW pair of R. americana is 2.13, and the average SC length per RN is 4.2 microm. The locations of the RNs along most of the long arms of the Z and W are not random, and the distances between pairs of RNs show interference. Thus, the pattern of RNs in this mostly euchromatic ZW pair is identical to that of autosomes. From the present and previous data, it is concluded that the ZW pair of R. americana is in a primitive stage of chromosomal differentiation, in which recombination is restricted only in the small short arm and in the pericentromeric region. PMID- 9364945 TI - Physical mapping of genetic markers to chromosome 30 using a trisomic horse and evidence for maternal origin of the extra chromosome. PMID- 9364946 TI - Usefulness of MRI for the pre-operative evaluation of the pulmonary arteries in Tetralogy of Fallot. AB - Adequate pre-operative evaluation of patients with Tetralogy of Fallot (TF) includes cine-angiography to delineate the pulmonary vasculature and the coronary artery anatomy and to demonstrate the presence of multiple ventricular septal defects (VSDs). All other information is obtained from color-Doppler echocardiography. Magnetic resonance imaging (MRI), using the spin-echo sequence and cine-angiography was employed on 18 patients with TF, four of whom had aorto pulmonary shunts. Mean age at MRI was 12.9 m (SD 2.3 m) and 14.3 m (SD 2.8 m) at cine-angiography. To compare MRI and cine-angiography we measured the ascending aorta, the main, the left and right pulmonary arteries and each structure at three levels. Diagnostic agreement between the two imaging methods was found if, for each modality, one of the three measurements in one structure differed by more than 40% from the other two measured in case of a local stenosis, and the diameter of the main pulmonary artery was less than 60% of the aorta to diagnose hypoplasia of the main pulmonary artery. There was close agreement between cine angiography and MRI. With regard to the intracardiac anatomy, MRI was superior to color-Doppler-echocardiography in the depiction of aortic override and of right ventricular hypertrophy. In three cases local stenoses in the pulmonary arteries were detected by MRI and cine-angiography. Hypoplasia of the main pulmonary artery was detected by MRI in six patients and by cine-angiography in five patients. Cine-angiography missed one case of hypoplasia. In the remaining 11 patients normal findings were found by MRI and cine-angiography. For the demonstration of shunts, gradient-recalled-echo MRI is expected to give better results than the spin-echo sequence which depicted two out of four shunts in this series. Cine-angiography can be substituted by MRI in delineating the pulmonary arteries. New developments in MRI indicate the feasibility of delineating the coronary arteries. PMID- 9364947 TI - Initial MRI findings of non-traumatic osteonecrosis of the femoral head in renal allograft recipients. AB - Fifty-one renal allograft recipients (15-62 years old, mean: 37 years) were monitored for 2.5-6.5 years (average: 4.3 years) after surgery by using magnetic resonance imaging (MRI) to find (i) initial signs of osteonecrosis of the femoral head (ONF), (ii) the presence of bone marrow edema as an initial sign of ONF, (iii) any changes of MRI patterns, and (iv) the relationship between these MRI findings and prognosis. MRI was performed preoperatively (baseline), and whenever possible during the 6-9th week, 12-16th week, 12th month, and yearly thereafter. T1- and T2-weighted images were obtained by using a spin echo technique. Abnormalities were first detected on MRI of 23 femoral heads in 13 patients between 6 weeks and 12 months. All lesions first showed a low intensity band on T1-weighted images and a high intensity band on T2-weighted images. No symptoms or diffuse patterns, such as bone marrow edema, preceded the appearance of the band pattern. After the 12th month, no new abnormal findings on MRI were detected. The lesions were classified into Type A, B, or C, according to the location. 12 of the 16 Type C femoral head lesions, which extend beyond the medial two thirds of the weight-bearing portion of the acetabulum, became symptomatic 7-14 months after transplantation and then progressed to collapse. Bone marrow edema appeared with radiological collapse and symptoms. With the exception of five lesions in three patients who failed to be MR imaged until 12 months postoperatively, all lesions were first detected on MRI within 16 weeks after transplantation. We therefore postulate that the ischemic event that causes ONF will have occurred within 12 weeks after transplantation, considering the time lag of reparative reaction to the dead bone. PMID- 9364948 TI - Liver positive enhancement after injection of superparamagnetic nanoparticles: respective role of circulating and uptaken particles. AB - Superparamagnetic nanoparticles have both high r1 and r2 relaxivities responsible for positive or negative enhancement properties. The aim of this study was to investigate to what extent perfusion (circulating particles) and uptake (clustered particles) mechanisms contribute to liver positive or negative enhancement using two different particles, superparamagnetic iron oxides (ferumoxides, AMI 25) and ultrasmall superparamagnetic iron oxides (ferumoxtran, AMI-227). Uptake kinetics were studied after intravenous injection of 20 micromol Fe/kg ferumoxtran on a washout liver model. Livers of 82 rats were surgically isolated and washed with saline infusion. Imaging was performed ex vivo at 0.5T with T1- and T2-weighted sequences. Enhancement kinetics of the liver were studied in vivo using MRI up to 180 min post injection of 20 micromol Fe/kg ferumoxtran (time response study) or 10, 20, 40 micromol Fe/kg ferumoxtran and 20 micromol Fe/kg ferumoxides (dose response study.) Particle uptake occurred early and resulted in a negative enhancement of the washed livers 15 min after injection of both T1 and T2 sequences. In vivo, a positive enhancement was only seen during the first five min with the lowest dose of ultrasmall superparamagnetic iron oxides and the T1 sequence. Uptake and clustering of the particles induced a negative liver enhancement. During the first minutes after injection, when uptake has not significantly occurred, perfusion imaging of the liver at a dose of 10 micromol Fe/kg results in a positive enhancement with T1 weighted sequences. PMID- 9364949 TI - Low density barium and bentonite mixture versus high density barium: a comparative study to optimize negative gastrointestinal contrast agents for MRI. AB - The purpose of this study was to compare the patient tolerance and efficacy, as magnetic resonance imaging negative oral contrast agents, of a mixture of clay compound bentonite and low density barium sulfate suspension with that of higher density barium sulfate. Twenty patients were randomized into two groups: 10 patients receiving a mixture of low concentration 60% w/v barium sulfate plus 2.5% w/v bentonite, and 10 patients receiving 220% w/v barium sulfate Liuqid-HD (E-Z-EM, Westbury, NY). Post-contrast Spin-echo (SE) T1- and T2-weighted images (WI) were obtained on a 1.0T magnet. Two independent readers scored the overall intraluminal signal intensity and delineation of the gastrointestinal tract and adjacent organs. Patient acceptance was evaluated via a short questionnaire, by recording spontaneous comments and documenting the quantity of contrast agent ingested. There was greater intraluminal bowel signal reduction and organ delineation with 220% w/v barium than with the barium-bentonite mixture on both SE T1WI (p = 0.03) and SE T2WI (p = 0.42). With both agents there was greater signal reduction on SE T2WI than SE T1WI. Higher scores for organ delineation for both contrast agents were seen with SE T1WI. With 220% w/v barium, there was significantly better delineation of the pancreatic body (p = 0.02) and pancreatic tail (p = 0.02) on T1WI compared with SE T2WI. With the barium-bentonite mixture, SE T1WI showed improved delineation of jejunum compared with SE T2WI (p = 0.03). There were no statistically significant differences between the volume of contrast ingested in the two groups. Abdominal cramps were recorded for one patient in each group. These results suggest that barium-bentonite mixture, although useful as a negative gastro-intestinal contrast agent, is not as effective as 220% w/v barium. Further studies with a larger patient population and concentration optimization studies are needed. PMID- 9364950 TI - Localization of ischemia in canine hearts using tagged rotated long axis MR images, endocardial surface stretch and wall thickening. AB - Tagged magnetic resonance imaging allows the noninvasive measurement of regional systolic myocardial deformations and helps localize ischemic regions in the left ventricle (LV). The objective of this study was to evaluate the potential accuracy of localizing ischemic regions in the LV using endocardial and epicardial data obtained from tagged rotated long axis images. Nine canine hearts with acute ischemia induced by coronary artery ligation were imaged along four long axis planes rotated around the LV long axis, at end diastole and end systole. Each plane was tagged by four parallel lines perpendicular to the LV long axis. Tracing the endocardial and epicardial intersection points of the tag lines, 24 myocardial cuboids were reconstructed for each LV at end diastole and end systole. Endocardial surface stretch and transmural systolic thickening were calculated for each cuboid. The functional data were compared to perfusion data obtained from postmortem monastral blue staining of the heart. The ability of each functional index to discriminate between ischemic and non-ischemic regions was assessed using the "t"-statistic. The potential accuracy in localizing ischemia was evaluated by studying the corresponding sensitivity-specificity curves. The results demonstrate that adequate discrimination and localization can be obtained with both functional indices. However, endocardial surface stretch is advantageous as it uses only endocardial data and can save 50% of the post processing time. PMID- 9364951 TI - The effects of a butanediol treatment on acute focal cerebral ischemia assessed by quantitative diffusion and T2 MR imaging. AB - Increased water T2 values indicates the presence of vasogenic edema. Decreased apparent diffusion coefficient (ADC) maps reveal ischemic areas displaying cytotoxic edema. ADC and T2 abnormalities spread through the middle cerebral artery (MCA) territory up to 24 h after middle cerebral artery occlusion (MCAO). Also, it was found that ADC and T2 contours closely match at 3.5 and 24 h. Since butanediol reduces vasogenic edema and improves energy status in various models of ischemia, we used these two techniques to investigate putative improvements in cytotoxic and vasogenic edema after permanent MCAO performed on rats. Rats were given no treatment (n = 8), or a treatment with 25 mmol/kg intraperitoneal (i.p.) butanediol (n = 5), 30 min before and 2.5 h after MCAO. Quantitative ADC and T2 maps of brain water were obtained, from which the volumes presenting abnormalities were calculated at various time points up to 24 h. Effects of butanediol on the ADC and T2 values in these areas were determined. Butanediol reduced neither the ADC volume nor the initial ADC decline. However, it reduced T2 volumes by 32% at 3.5 h and 15% at 24 h (p < 0.05), and reduced T2 increase in the striatum at 3.5 h post-MCAO. Therefore, our results show for the first time that a pharmacological agent such as butanediol can delay the development of vasogenic edema but does not limit the development of vasogenic edema but does not limit the development of cytotoxic edema. ADC imaging detects areas of severe metabolic disturbance but not moderately ischemic peripheral areas where butanediol is presumed to be more efficacious. PMID- 9364952 TI - Normalisation of metabolite images in 1H NMR spectroscopic imaging. AB - Single slice proton magnetic resonance spectroscopic images were taken from a volume of interest (VOI), which was localised using the point resolved spectroscopy (PRESS) sequence. Non-uniformities in the excitation profile of the VOI within the image plane were accounted for using a uniformity correction image. Metabolite images were divided on a voxel-by-voxel basis with a water image obtained from a VOI of the same spatial dimensions from a phantom acquisition. Normalisation procedures carried out on phantom metabolite images were needed to account for the spatial shift in the excitation profile of the VOI, which varies linearly with the chemical shift of the metabolite. Patient metabolite images were then normalised using a VOI water image from a phantom acquisition, which was spatially shifted according to the metabolite chemical shift. In a study of 14 stroke patients, metabolite maps of the distribution of choline, creatine and N-acetyl aspartate (NAA) were constructed. The spectral signal intensities from these metabolites in the infarcted and in the contralateral region were calculated using the raw maps and secondly with the same maps after the B1 normalisation process. In the initial analysis only the metabolite NAA showed a significant decrease, whilst all three metabolites showed a significant reduction in the normalised analysis. These results confirm that normalisation of PRESS localised images does have a significant bearing upon any quantitative measurements made using such images. PMID- 9364953 TI - Effect of ethanol and fructose on liver metabolism: a dynamic 31Phosphorus magnetic resonance spectroscopy study in normal volunteers. AB - In vivo 31Phosphorus magnetic resonance spectroscopy (31P-MRS) permits evaluation of dynamic changes of individual phosphorus-containing metabolites in the liver parenchyma, such as phosphomonoester (PME), adenosine triphosphate, and inorganic phosphate (Pi). Intravenous fructose load alters phosphorus metabolites and allows assessment of liver function by 31P-MRS. 31P-MRS data obtained in alcoholic liver disease are however inconclusive. To study the hypothesis that fructose load can be used to investigate metabolic effects of ethanol ingestion, the interaction of different metabolites--i.e., fructose and ethanol--were followed in vivo. Using a 1.5 Tesla magnetic resonance system, six healthy volunteers were examined in three sessions each: a session after administration of (a) fructose only (250 mg/kg) was compared with (b) fructose load after ethanol ingestion (0.8 g/kg). A control experiment (c) was done after ethanol only. Spectra were acquired using one-dimensional chemical shift imaging with a temporal resolution of 5 min. Following a fructose load, the concomitant uptake of ethanol showed drastic changes of individual metabolic steps of the hepatic metabolism (averages +/- standard deviation). While the velocity of the net formation of PME (relative increase 0.46 +/- 0.11 without ethanol vs. 0.61 +/- 0.25 with ethanol) and the use of adenosine triphosphate (-0.13 +/- 0.03 vs. 0.16 +/- 0.03) and Pi (-0.022 +/- 0.009 vs. -0.021 +/- 0.004) were not significantly affected by ethanol uptake, a significant (p < 0.01) reduction of PME degradation (31.3 +/- 9.4 vs. 61.9 +/- 16.9 relative total area) and absence of an overshoot for Pi (10.5 +/- 4.9 vs. -7.1 +/- 5.3 relative area 13 min to 43 min) was observed after ethanol administration. Dynamic 31P-MRS allows the observation of individual steps of hepatic metabolism in situ; fructose metabolism in the human liver is slowed down by concomitant ethanol ingestion after the phosphorylation step of fructose. This could be explained by inhibition of aldolase rather than ethanol-induced changes of the hepatic redox state. Fructose load can be used to study effects of alcohol ingestion and might therefore be useful in patients with alcoholic liver disease. PMID- 9364954 TI - Temporal brain imaging by a rapid scan ESR-CT system in rats receiving intraperitoneal injection of a methyl ester nitroxide radical. AB - We performed in vivo ESR-CT (electron spin resonance-computed tomography) on rats' heads, in which the blood-brain barrier-permeable nitroxide radical, 3 methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM) was injected intraperitoneally, using a rapid scan ESR-CT system operating at 700 MHz. In a spatiotemporal study we found that different regions of the brain showed differences in the rate of decay of the radical. Repeated injection of PCAM gave clear ESR-CT images of the brain. We think that the present method is useful for evaluating the capacity to eliminate exogenous free radicals in some parts of the brain. PMID- 9364955 TI - Non-destructive visualisation in three dimensions of freezing events in flowers of blackcurrant (Ribes nigrum L.) using spin-echo NMR microscopy. AB - Flowers of blackcurrant (Ribes nigrum L.) were subjected to freezing stress in vivo, and the resulting damage examined in three dimensions using a spin-echo nuclear magnetic resonance imaging sequence. Increased signal intensity was detected in the damaged flowers, particularly at the base of the style, in T2 weighted images. This is thought to be the result of intracellular freezing, which causes membrane damage and leakage of cellular contents. It is proposed that this represents the main site of damage within the flowers. The imaging of flowers of differing developmental ages showed larger increases in signal from fully open flowers after freezing damage compared with those in the initial stages of bud, suggesting that the enclosed nature of the flower buds may have a protective effect on the sensitive stylar base. The use of three-dimensional nuclear magnetic resonance imaging provides a rapid and effective means for the visualisation of freezing events within floral tissues; the effective resolution of the images enables greater accuracy and clarity in interpretation than hitherto possible in two dimensions. PMID- 9364956 TI - Median nerve hamartoma: MR imaging using chemical shift techniques. AB - Magnetic resonance imaging findings of median nerve hamartoma are presented in three patients with palpable wrist masses and median neuropathy. Fat-suppressed T1-weighted images demonstrated adipose tissue separating the neural and fibrous tissue bundles in two of three patients, which results in the distinctive appearance of these tumors on magnetic resonance imaging. Fibrous tissue appeared as enhancing longitudinal bundles within the tumor on gadolinium enhanced fat suppressed T1-weighted images. PMID- 9364957 TI - Adult intussusception: demonstration by current MR techniques. AB - We describe magnetic resonance findings in three patients with small bowel intussusception from different etiologies including idiopathic, adenomatous polyps, and hamartomatous polyps. Magnetic resonance findings showed a bowel within-bowel appearance in two patients and a coiled-spring appearance in one patient. These findings were best shown on T2-weighted images, and clear definition was present on breathing independent T2-weighted images using half fourier acquisition snap shot turbo spin echo T2-weighted images. PMID- 9364958 TI - Thrombophlebitis of the inferior vena cava involving the retroperitoneum with Crohn's disease: MR demonstration. AB - We present a case of thrombophlebitis of the inferior vena cava (IVC) with Crohn's disease after intestinal perforation and prolonged indwelling of a catheter in the IVC. Magnetic resonance imaging demonstrated abnormal thickening and enhancement of the IVC wall. In addition, IVC thrombus formation was shown. The abnormal enhancement extended from the wall in the pericaval tissue and into the retroperitoneum, and regressed as the Crohn's disease subsided. PMID- 9364959 TI - Post radiation hemorrhagic cystitis: MR findings. AB - We report on the magnetic resonance findings in two patients with hemorrhagic cystitis secondary to radiation therapy. One patient's bladder wall was high in signal intensity on T1-weighted fat-suppressed spoiled gradient echo and low in signal intensity on T2-weighted fat-suppressed spin echo images, findings consistent with intracellular methemoglobin in the setting of subacute intramural hemorrhage. The second patient's bladder wall had regions that were low in signal intensity on T1-weighted fat-suppressed spin echo and high in signal intensity on T2-weighted fat-suppressed spin echo, and other regions that were high in signal intensity on T1-weighted fat suppressed spin echo and on T2-weighted fat suppressed spin echo images, findings that were consistent with active bleeding and late subacute hemorrhage, respectively. Imaging findings correlated with the patients' clinical picture. Our two cases illustrate that magnetic resonance images may demonstrate changes of hemorrhagic cystitis and may permit determination of disease acuity. PMID- 9364960 TI - Pulmonary artery sling diagnosed by magnetic resonance imaging. PMID- 9364961 TI - Large craniopharyngioma extending to the posterior cranial fossa. AB - Craniopharyngiomas are most commonly located extra-axially in the sellar or suprasellar area. They are benign but aggressive neoplasms. This paper reports an 8-year-old girl with a large craniopharyngioma originating from the suprasellar region and extending to the posterior cranial fossa down to the region of the foramen magnum. PMID- 9364962 TI - Evolution of the genus Leishmania revealed by comparison of DNA and RNA polymerase gene sequences. AB - Previous hypotheses of Leishmania evolution are undermined by limitations in the phylogenetic reconstruction method employed or due to the omission of key parasites. In this experiment, sequences of the gene encoding the DNA polymerase alpha catalytic polypeptide (POLA) were analysed phylogenetically in combination with those encoding the RNA polymerase II largest subunit gene (RPOIILS) to infer a comprehensive phylogeny of Leishmania. Nineteen species of parasites were studied, comprising representatives of each Leishmania species-complex (Leishmania Leishmania tropica, Leishmania Leishmania donovani, Leishmania Leishmania mexicana, Leishmania Leishmania hertigi and Leishmania Viannia braziliensis), as well as parasites of questionable taxonomy (Leishmania herreri, Sauroleishmania adleri, Sauroleishmania deanei, Sauroleishmania gymnodactyli and Sauroleishmania tarentolae). The analyses presented here provide strong support for the hypothesis that the Leishmania that infect reptiles (also known as Sauroleishmania) evolved from mammalian Leishmania. One implication of this finding is that the taxonomic definition of Leishmania should be broadened to encompass characteristics of the reptilian parasites. However, this taxonomic revision is complicated in that Leishmania (L.) hertigi, Leishmania (L.) deanei and Leishmania herreri, which exhibit some biological properties of Leishmania, are more closely related to Endotrypanum on the basis of these sequence comparisons. Consequently, the taxonomic discrimination between Leishmania that infect mammals, Leishmania that infect reptiles and Endotrypanum may be more problematic than has been previously thought. Since our resulting phylogenetic hypothesis is supported by the analyses of two different genes, we speculate on the origin and evolutionary expansion of this lineage of kinetoplastid protozoa. PMID- 9364964 TI - Molecular characterization of the heat-inducible LmSTI1 protein of Leishmania major. AB - We have recently isolated a cDNA encoding the Leishmania major homologue of the yeast stress-inducible protein STI1. Southern blot analyses indicate that this protein is encoded by a single copy gene in L. major and that this gene is highly conserved throughout the Leishmania genus. The STI1 gene is constitutively expressed in both L. major promastigotes and amastigotes however, STI1 transcript levels can be upregulated in promastigotes by a shift in culture temperature from 26 to 37 degrees C. Upregulation of transcript was detectable within 5' of heat shock and continued to increase for a further 8 h before returning to constitutive levels. In addition, biosynthetic incorporation of [35S]methionine followed by immunoprecipitation revealed an increase in the level of nascent STI1 protein synthesized when promastigote cultures were shifted from 26 to 37 degrees C. The L. major STI1 protein and the heat shock proteins Hsp83 and Hsp70 form a salt-sensitive complex in L. major promastigotes as evidenced by co immunoprecipitation using an antiserum specific for L. major STI1. Furthermore, this complex can be reconstituted in vitro by adding recombinant STI1 containing an amino-terminal histidine tag to promastigote lysate and subsequent purification using metal chelate affinity chromatography. PMID- 9364963 TI - Resistance to antifolates in Plasmodium falciparum monitored by sequence analysis of dihydropteroate synthetase and dihydrofolate reductase alleles in a large number of field samples of diverse origins. AB - Resistance of Plasmodium falciparum to antifolate chemotherapy is a significant problem where combinations such as Fansidar (pyrimethamine-sulfadoxine; PYR-SDX) are used in the treatment of chloroquine-resistant malaria. Antifolate resistance has been associated with variant sequences of dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS), the targets of PYR and SDX respectively. However, while the nature and distribution of mutations in the dhfr gene are well established, this is not yet the case for dhps. We have thus examined by DNA sequence analysis 141 field samples from several geographical regions with differing Fansidar usage (West and East Africa, the Middle East and Viet Nam) to establish a database of the frequency and repertoire of dhps mutations, which were found in 60% of the samples. We have also simultaneously determined from all samples their dhfr sequences, to better understand the relationship of both types of mutation to Fansidar resistance. Whilst the distribution of mutations was quite different across the regions surveyed, it broadly mirrored our understanding of relative Fansidar usage. In samples taken from individual patients before and after drug treatment, we found an association between the more highly mutated forms of dhps and/or dhfr and parasites that were not cleared by antifolate therapy. We also report a novel mutation in a Pakistani sample at position 16 of DHFR (A16S) that is combined with the familiar C59R mutation, but is wild-type at position 108. This is the first observation in a field sample of a mutant dhfr allele where the 108 codon is unchanged. PMID- 9364965 TI - Characterization of cDNAs encoding serine proteinases from the soybean cyst nematode Heterodera glycines. AB - Three cDNAs encoding serine proteinases (HGSPI-III) were isolated from a cDNA library constructed from feeding females of Heterodera glycines. The library was screened with three separate serine proteinase gene fragments amplified from cDNA of H. glycines using consensus oligonucleotide primers. Each predicted protein contains a secretion signal sequence, a propeptide and a mature protein of 226 296 amino acids. One of the predicted enzymes, HGSP-II has 41% identity to a chymotrypsin-like enzyme from the mollusc, Haliotis rufescens, and analysis of key residues involved in substrate binding also suggests a chymotrypsin-like specificity. HGSP-I and HGSP-III show greatest homology to kallikreins but sequence analysis does not allow prediction of their substrate preferences. Southern blot analysis suggests that HGSP-II and HGSP-III are encoded by single copy genes in contrast to HGSP-I which may have two or more homologues. The regions encoding the mature proteinases were cloned into an expression vector and recombinant protein produced in Escherichia coli. Both HGSP-I and HGSP-II were shown, after refolding, to cleave the synthetic peptide N-CBZ-Phe-Arg-7-amido-4 methylcoumarin, and this activity could be inhibited by the cowpea trypsin inhibitor, CpTI. HGSP-III showed no activity against the synthetic substrates tested. The information gained from these studies indicates that serine proteinases are an important group of enzymes in H. glycines and further characterization will aid the development of a proteinase inhibitor-based approach for transgenic plant resistance to plant parasitic nematodes. PMID- 9364966 TI - The expression of Toxoplasma proteins in Neospora caninum and the identification of a gene encoding a novel rhoptry protein. AB - Genes for the Toxoplasma gondii dense granule and rhoptry proteins nucleoside triphosphate hydrolase 3 and ROP2 were expressed at high levels in the closely related parasite N. caninum. The protein products were processed appropriately and were targeted to their correct secretory organelles. NTPase 3 was secreted into the parasitophorous vacuole. The utility of this system was demonstrated in the analysis of a new open reading frame identified upstream of two identical copies of the ROP2 gene. The unknown open reading frame was introduced into Neospora, and transfected parasites were analyzed by immunoblot with antibodies to known T. gondii rhoptry protein families. The transfected Neospora expressed a novel 52 kDa protein, designated ROP8, which localized in the rhoptries. These results illustrate that transfection of known Toxoplasma genes into N. caninum can be used to study their expression, processing and targeting in an immunologically distinct background. They also illustrate the usefulness of N. caninum transfection in the identification and subcellular distribution of proteins encoded by previously uncharacterized Toxoplasma genes. PMID- 9364967 TI - Purification and properties of a membrane aminopeptidase from Ascaris suum muscle that degrades neuropeptides AF1 and AF2. AB - We have identified on the membranes of the locomotory muscle of Ascaris suum an amastatin-sensitive aminopeptidase that hydrolyses the bioactive neuropeptides AF1 (KNEFIRF-NH2) and AF2 (KHEYLRF-NH2), by cleavage of the Lys1-Asn2 and Lys1 His2 peptide bonds, respectively. AF2 (1.2 nmol of HEYLRF-NH2 formed min[-1] (mg protein[-1])) was hydrolysed at a faster rate compared to AF1 (0.2 nmol of NEFIRF NH2 formed min[-1] (mg protein[-1])). AF1 hydrolysis by the aminopeptidase was inhibited by the amastatin (IC50, 9.0 microM), leuhistin (IC50, 1.25 microM) but was insensitive to puromycin, indicating a similarity to mammalian aminopeptidase N. The enzyme was also inhibited by arphamenine B (IC50, 9.0 microM), (2S, 3R)-3 amino-2-hydroxy-4-(4-nitrophenyl)butanoyl-L-leucine (IC50, 8.0 microM), bestatin (IC50, 15.0 microM) and 1 mM 1-10 bis-phenanthroline. The detergent Triton X-100 solubilised enzyme had a pI of 5.0 and after 1000-fold purification by ion exchange chromatography, appeared to have a Mr of around 240,000 by SDS-PAGE. The purified aminopeptidase had a Km of 534 microM for the hydrolysis of AF1 and cleaved Phe1 from FMRF-NH2, but was unable to hydrolyse DFMRF-NH2 or FDMRF-NH2. The aminopeptidase that we have described in this report might have a role in the extracellular metabolism and inactivation of neuropeptides acting on the locomotory muscle of A. suum. PMID- 9364968 TI - Developmentally regulated expression of pfs16, a marker for sexual differentiation of the human malaria parasite Plasmodium falciparum. AB - Sexual differentiation is essential for the transmission of Plasmodium to mosquitoes and therefore, for the spread of malaria. The molecular mechanisms underlying sexual differentiation are poorly understood but may be elucidated by a detailed study of the regulation of expression of sexual stage specific genes. In the present work we describe the differential expression of the gene encoding the sexual stage specific protein, Pfs16. We have conducted a comparative analysis of pfs16 promoter activity, RNA levels and the rate of de novo protein synthesis during development of Plasmodium falciparum. Furthermore, we have determined the pattern of expression of pfs16 transcripts at the single cell level by in situ hybridisation. We show that the expression of pfs16 is induced immediately following the invasion of a red blood cell in sexually committed ring stage parasites and continues throughout gametocytogenesis and in macrogametes. The expression of pfs16 is regulated at the level of transcription initiation and modulated by a post-transcriptional process. These results demonstrate that the expression of the pfs16 gene is the earliest event in the sexual differentiation process of P. falciparum described to date. PMID- 9364969 TI - Purine nucleobase transport in bloodstream forms of Trypanosoma brucei is mediated by two novel transporters. AB - The mechanism and inhibitor sensitivity of hypoxanthine transport by bloodstream forms of Trypanosoma brucei brucei was investigated. The dose response curve for the inhibition of hypoxanthine transport (1 microM) by guanosine was biphasic; approximately 90% of transport activity was inhibited with a Ki value of 10.8 +/- 1.8 microM, but 10% of the activity remained insensitive to concentrations as high as 2 mM. These two components of hypoxanthine transport are defined as guanosine-sensitive (H2) and guanosine-insensitive (H3). Hypoxanthine influx by both components was saturable, but there was a marked difference in their Km values (123 +/- 15 nM and 4.7 +/- 0.9 microM for H2 and H3, respectively) although the Vmax values (1.1 +/- 0.2 and 1.1 +/- 0.1 pmol (10[7] cells)[-1] s[ 1], n = 3) were similar. Hypoxanthine uptake via the H2 carrier was inhibited by purine bases and analogues as well as by some pyrimidine bases and one nucleoside (guanosine), whereas the H3 transporter was sensitive only to inhibition by purine nucleobases. H2-mediated hypoxanthine uptake was inhibited by ionophores, ion exchangers and the potential H+-ATPase inhibitors, N,N' dicyclohexylcarbodiimide (DCCD) and N-ethylmaleimide (NEM). Measurements of the intracellular pH and membrane potential of bloodstream trypanosomes in the presence and absence of these agents established a linear correlation between protonmotive force and rate of [3H]hypoxanthine (30 nM) uptake. We conclude that hypoxanthine transport in bloodstream forms of T. b. brucei occurs by two transport systems with different affinities and substrate specificities, one of which, H2, appears to function as a H+-/hypoxanthine symporter. PMID- 9364970 TI - Characterization of a variant erythrocyte surface antigen (VESA1) expressed by Babesia bovis during antigenic variation. AB - Babesia bovis, an intraerythrocytic, protozoal parasite of cattle, undergoes clonal antigenic variation (Allred DR, Cinque RM, Lane TJ, Ahrens KP. Infect Immun 1994;62:91-98). This ability could provide a mechanism by which the parasite escapes host immune defenses to establish chronic infection. Previous work identified two parasite-derived antigens of Mr 128,000 and 113,000 that were present on the surface of the infected erythrocyte and appeared to be associated with clonal antigenic variation (Allred DR, Cinque RM, Lane TJ, Ahrens KP. Infect Immun 1994;62:91 98). Two monoclonal antibodies (mAbs), 3F7.1H11 and 4D9.1G1, which recognize the variant erythrocyte surface antigen (VESA1) have been identified. These mAbs react only with the surface of erythrocytes infected with the B. bovis C9.1 clone in live-cell immunofluorescence assays. In both conventional and surface immunoprecipitations, the mAbs precipitate a variant antigen doublet that matches in mass the infected red blood cell (IRBC) surface antigens precipitated with bovine serum. In contrast, Western blot analysis revealed that only the Mr 128,000 polypeptide is recognized by the mAbs. Neither mAb recognizes antigenically variant progenitor or progeny parasite clones in any of the immunoassays, confirming the involvement of this antigen in rapid clonal antigenic variation. Failure to label this antigen with [9,10(n)-3H]myristic acid, [9,10(n)-3H]palmitic acid or D-[6-3H]glucosamine indicates that these polypeptides are neither N-glycosylated nor fatty acylated. Identity of the variant antigen recognized by the mAbs with that putatively identified with immune serum was confirmed by comparison of partial proteolytic digestion products. Unambiguous identification of the VESA1 antigen as a component of antigenic variation will facilitate characterization of the events leading to antigenic variation on the B. bovis-infected erythrocyte surface and its significance to parasite survival during chronic infection. PMID- 9364971 TI - Identification and characterization of SRS1, a Toxoplasma gondii surface antigen upstream of and related to SAG1. AB - Previous investigations of the major surface antigen (SAG1) promoter of Toxoplasma gondii indicated an ability to function bi-directionally in transient transformation assays at least. This suggests there might be another tachyzoite specific gene being divergently transcribed from the SAG1 promoter in its normal chromosomal location. To investigate this possibility we have characterized the region upstream of SAG1 and report here a co-directional transcription unit coding for a probable GPI-anchored surface protein with homology to SAG1 and SAG3. This antigen, which had not previously been identified in surface iodination experiments is given the acronym SRS1, for SAG1-related sequence 1. Genomic organization and sequence of a full-length cDNA of SRS1 are presented. Antisera against a recombinant SRS1 protein produced in Escherichia coli, recognize a specific band of 46 kDa in parasite lysates which corresponds to the largest of the GPI-anchored proteins by Western blot. The possible role of this previously unidentified surface antigen is discussed. PMID- 9364973 TI - A phylogenetic view on the genus Phytomonas. PMID- 9364972 TI - Identification of an endoplasmic reticulum-resident calcium-binding protein with multiple EF-hand motifs in asexual stages of Plasmodium falciparum. AB - An endoplasmic reticulum-located, calcium-binding protein, with an apparent molecular weight (Mr) of approximately 40,000 (PfERC), has been identified in the asexual stages of the malaria parasite, Plasmodium falciparum. This protein appears to be equivalent to a previously described gametocyte protein, Pfs40, which was reported to be expressed on the gametocyte surface (Rawlings DJ, Kaslow DC. J Biol Chem 1992;267:3976-3982). Sequencing of the 3' end of the gene revealed the omission of a single base in the 3' region of the published sequence. The corrected gene sequence encodes a C-terminal IDEL motif, which indicates residency of the 40 kDa protein within the endoplasmic reticulum. The predicted C-terminal region also appears to contain a sixth EF-hand calcium binding domain, which suggests that PfERC is related to previously reported ER localized calcium-binding proteins, namely reticulocalbin and ERC-55 (Ozawa M. J. Biochem. 1995;117:1113-1119; Weis K, Griffiths G, Lamond AI. J. Biol. Chem. 1994;269:19142-19150). The presence of the 40 kDa calcium-binding protein in malaria parasites was confirmed using 45Ca2+-blotting and partial protein sequencing of the corresponding Coomassie blue-stained polypeptide. Confocal immunofluorescence microscopy of asexual stage parasites was used to show that PfERC co-localizes with the known ER-located protein, Pfgrp. Analysis of immunoblots of tightly synchronized parasites showed that expression of PfERC increases with increasing maturity of the parasite. We propose that PfERC is a member of the reticulocalbin family of calcium-binding proteins and may play a role in protein trafficking in the malaria parasite. PMID- 9364974 TI - Cloning and sequence analysis of a gene encoding an erythrocyte binding protein from Plasmodium cynomolgi. PMID- 9364975 TI - The beta-tubulin gene of Cryptosporidium parvum. PMID- 9364976 TI - Characterization of C-terminal merozoite surface protein-1 baculovirus recombinant proteins from Plasmodium vivax and Plasmodium cynomolgi as recognized by the natural anti-parasite immune response. PMID- 9364977 TI - Trypanosoma cruzi: circularization of linear DNA fragments prior to integration during generation of stable transformants. PMID- 9364978 TI - A novel thrombomodulin gene mutation in a patient suffering from sagittal sinus thrombosis. AB - Thrombomodulin is an endothelial cell membrane glycoprotein that promotes protein C activation. It has been clearly demonstrated that the anticoagulant functions of the protein C system are important in the prevention of thromboembolic disease. Patients with protein C or protein S deficiency and/or resistance to activated protein C (APC resistance) are at higher risk for developing thromboembolic disease. The first mutation in the thrombomodulin gene was discovered in an American patient suffering from pulmonary embolism at the age of 45 (Ohlin and Marlar 1995). Here we report a case of sagittal sinus thrombosis in a 42-year-old Swedish woman. She was found to carry a heterozygous point mutation changing G127 to A, predicting an Ala25 to a Thr change in the mature thrombomodulin protein. This mutation was also found in her 16-year-old daughter, who so far has not suffered from any thrombotic events. The patient had no other detectable prothrombotic genetic defects associated with the coagulation system. This case supports the hypothesis of an association between mutations in the thrombomodulin gene and venous thrombosis. PMID- 9364980 TI - Thrombin generation measured ex vivo following microvascular injury is increased in SLE patients with antiphospholipid-protein antibodies. AB - Antiphospholipid-protein antibodies (APA) include lupus-type anticoagulant (LA) and antibodies recognizing complexes of anionic phospholipids (e.g. cardiolipin) and proteins (e.g. prothrombin and beta2-glycoprotein I). The presence of APA is associated with an increased risk of both arterial and venous thrombosis. However, the pathogenic mechanism leading to thrombosis in patients with APA remains unclear. We studied 32 patients with systemic lupus erythematosus (SLE) who were divided into two groups depending on the presence (n = 19) or absence (n = 13) of APA. Healthy volunteers (n = 12) matched by age and sex served as controls. In all subjects LA and IgG class anticardiolipin antibodies (ACA) were determined. Thrombin generation was monitored ex vivo measuring fibrinopeptide A (FPA) and prothrombin fragment F1 + 2 (F1 + 2) in blood emerging from a skin microvasculature injury, collected at 30 second intervals. In subjects with antiphospholipid antibodies mean FPA and F1 + 2 concentrations were significantly higher at most blood sampling times than in controls. In some SLE patients with APA the process of thrombin generation was clearly disturbed and very high concentrations of fibrinopeptide A were detected already in the first samples collected. Two minutes after skin incision SLE patients without APA produced slightly more FPA, but not F1 + 2, as compared to healthy subjects. Mathematical model applied to analyze the thrombin generation kinetics revealed that APA patients generated significantly greater amounts of thrombin than healthy controls (p = 0.02 for either marker). In contrast, in the same patients generation of thrombin in recalcified plasma in vitro was delayed pointing to the role of endothelium in the phenomenon studied. In summary, these data show for the first time that in SLE patients with antiphospholipid-protein antibodies thrombin generation after small blood vessel injury is markedly increased. Enhanced thrombin generation might explain thrombotic tendency observed in these patients. PMID- 9364979 TI - Effects of gemfibrozil and ciprofibrate on plasma levels of tissue-type plasminogen activator, plasminogen activator inhibitor-1 and fibrinogen in hyperlipidaemic patients. AB - Evaluation of fibrate treatment in humans has focused primarily on its anti lipidaemic effects. A potentially favourable haemostasis-modulating activity of fibrates has also been recognized but the data are not consistent. We sought to learn more about this variability by examining the effects of gemfibrozil and ciprofibrate on plasma levels of tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1) and fibrinogen in primary hyperlipidaemic patients after six and twelve weeks of treatment using different assay systems for PAI-1 and fibrinogen. Although both fibrates effectively lowered triglyceride and cholesterol levels, no effect on the elevated baseline antigen levels of t-PA and PAI-1 was observed after fibrate treatment. However, both fibrates influenced plasma fibrinogen levels, albeit in a different way. Fibrinogen antigen levels were elevated by 17.6% (p <0.05) and 24.3% (p <0.001) with gemfibrozil after six and twelve weeks, respectively, whereas with ciprofibrate there was no effect. Using a Clauss functional assay with either a mechanical end point or a turbidity-based end point, no significant change in fibrinogen levels was seen after six weeks of gemfibrozil treatment. However, after twelve weeks, gemfibrozil enhanced functional fibrinogen levels by 7.2% (p <0.05) as assessed by the Clauss mechanical assay, but decreased functional fibrinogen levels by 12.5% (p <0.0001) when a Clauss assay based on turbidity was used. After six or twelve weeks of ciprofibrate treatment, functional fibrinogen levels were decreased by 10.1% (p <0.001) and 10.5% (p <0.0001), respectively on the basis of Clauss mechanical and by 14.2% (p <0.001) and 28.2% (p <0.0001), respectively with the Clauss turbidimetric assay. A remarkable and consistent finding with both fibrates was the decrease in functionality of fibrinogen as assessed by the ratio of functional fibrinogen (determined by either of the two Clauss assays) to fibrinogen antigen. Taken together, our results indicate that at least part of the variability in the effects of fibrates on haemostatic parameters can be explained by intrinsic differences between various fibrates, by differences in treatment period and/or by the different outcomes of various assay systems. Interestingly, the two fibrates tested both reduced the functionality of fibrinogen. PMID- 9364981 TI - High antibody levels to prothrombin imply a risk of deep venous thrombosis and pulmonary embolism in middle-aged men--a nested case-control study. AB - Antibodies against phospholipid-binding plasma proteins, such as beta2 glycoprotein I (beta2-GPI) and prothrombin, are associated with thromboembolic events in patients with systemic lupus erythematosus and also in subjects with no evident underlying diseases. We wanted to examine whether increased levels of antibodies to negatively-charged phospholipids (cardiolipin), to phospholipid binding plasma proteins beta2-GPI and prothrombin and to oxidised low-density lipoprotein (LDL) were associated with risk of deep venous thrombosis or pulmonary embolism in subjects with no previous thrombosis. The antibodies were measured in stored serum samples from 265 cases of deep venous thrombosis of the lower extremity or pulmonary embolism occurring during a median follow-up of about 7 years and from 265 individually matched controls. The study subjects were middle-aged men participating in a cancer prevention trial of alpha-tocopherol and beta-carotene and the cases of thromboembolic events were identified from nationwide Hospital Discharge Register. The risk for thrombotic events was significantly increased only in relation to antiprothrombin antibodies. As adjusted for body mass index, number of daily cigarettes and history of chronic bronchitis, myocardial infarction and heart failure at baseline, the odds ratio per one unit of antibody was 6.56 (95% confidence interval 1.73-25.0). The seven highest individual optical density-unit values of antiprothrombin antibodies were all confined to subjects with thromboembolic episodes. In conclusion, the present nested case-control study showed that high autoantibody levels against prothrombin implied a risk of deep venous thrombosis and pulmonary embolism and could be involved in the development of the thrombotic processes. PMID- 9364982 TI - Risk factors for pregnancy associated venous thromboembolism. AB - In an attempt to reduce the incidence of pregnancy associated venous thromboembolism (PA-VTE), some researchers have advocated screening of all women for the factor V(Leiden) mutation during early pregnancy. We have conducted a large retrospective study (over 72,000 deliveries) to determine if this would be useful. Sixty-two objectively confirmed venous thrombotic events (51 DVT, 11 PE) were recorded at two maternity units in the UK. The incidence of DVT was 0.71 per 1000 deliveries (95% CI 0.5-0.9) with 0.50 occurring in the antenatal period (95% CI 0.34-0.66) and 0.21 in the puerperium (95% CI 0.11-0.31). The incidence of PE was 0.15 per 1000 deliveries (95% CI 0.06-0.24), 0.07 antenatal (95% CI 0.01 0.13) and 0.08 in the puerperium (95% CI 0.02-0.14). Of these 62, 50 attended for follow-up and thrombophilia screening. 28% of all episodes of PA-VTE had no clinical risk factor for thrombosis or an identifiable thrombophilic abnormality. Deficiency of antithrombin was identified in 12% of individuals (95% CI 3-21) and the factor V(Leiden) mutation in 8% (95% CI 0.5-15.5). Based on estimates of the prevalence of the factor V(Leiden) mutation in the population, we estimate that the thrombotic risk for a woman during pregnancy or the puerperium with the defect is approximately 1 in 400-500. This figure would not lend support to the idea of random screening for the mutation in early pregnancy. PMID- 9364983 TI - Bleeding classification in clinical trials: observer variability and clinical relevance. AB - To evaluate the bleeding classification in a recent trial on venous thrombosis treatment, a selection of reported bleeding episodes was adjudicated twice by an independent committee and graded by the treating physician and independent clinical experts on the clinical severity and impact on the patient's life. The kappa values for the dichotomy major bleeding versus minor or no bleeding were 0.79 (95% CI, 0.57-1.0) for the agreement between the two members of the adjudication committee and 0.77 (95% CI, 0.52-1.0) for the agreement between both adjudication sessions. The kappa values for the dichotomy major or minor bleeding versus no bleeding were 0.42 and 0.44. The weighted kappa values for the agreement between the treating physician and the independent experts were 0.76 for the clinical severity and 0.79 for the impact on the patient's life (95% CI, 0.63-0.88 and 0.70-0.89). The association between the adjudication result expressed as major bleeding or minor or no bleeding and the clinical grading by the treating physician resulted in an ROC curve with an area under the curve of 0.98 for the clinical severity and 0.99 for the impact on the patient's life. The dichotomy major or minor bleeding versus no bleeding resulted in areas under the curve of 0.70 and 0.66. In conclusion, the applied criteria for major bleeding are reproducible and clinically relevant. The criteria for minor bleeding are not reproducible and are less associated with the observed clinical relevance. PMID- 9364984 TI - Ultrasensitive fluorogenic substrates for serine proteases. AB - Selective, sensitive assays for the quantitation of serine proteases involved in coagulation and fibrinolysis have been developed employing fluorogenic substrates containing a 6-amino-1-naphthalenesulfonamide leaving group (PNS-substrates). Over one hundred substrates were evaluated for hydrolysis by the serine proteases of blood coagulation and fibrinolysis, and substrate structure-efficiency correlations were examined. PNS-substrates which contain Lys in the P1 position are specific for Lys-plasmin and are either not hydrolyzed or hydrolyzed at a relatively low rate by factor Xa, thrombin, or urokinase-type plasminogen activator (uPA). These substrates allow quantitation of Lys-plasmin at concentrations as low as 1 pM. Eighteen of over 90 substrates tested for factor XIa are hydrolyzed by this enzyme at a relatively high rate reaching a k(cat), value of 170 s(-1) and allowing quantitation of factor XIa at 10 fM. Eighteen of almost 90 PNS-substrates tested display high specificity for thrombin, some exceeding that for factor Xa by >10,000-fold and >100-fold for activated protein C (APC). Seven of these substrates have a k(cat) over 100 s(-1) and three of them have a K(M) below 1 microM. They allow the quantitation of thrombin at concentrations as low as 20 fM. For APC, uPA and the factor VIIa/tissue factor complex, quantitation is feasible at 1 pM concentration. For factor Xa and factor VIIa the limits are 0.4 pM and 40 pM respectively. The PNS-substrates presented in this study may be employed for the development of direct and sensitive serine protease assays. PMID- 9364985 TI - The effect of active site-inhibited factor VIIa on tissue factor-initiated coagulation using platelets before and after aspirin administration. AB - Active site-inactivated factor VIIa has potential as an antithrombotic agent. The effects of D-Phe-L-Phe-L-Arg-chloromethyl ketone-treated factor VIIa (FFR-FVIIa) were evaluated in a cell-based system mimicking in vivo initiation of coagulation. FFR-FVIIa inhibited platelet activation (as measured by expression of P-selectin) and subsequent large-scale thrombin generation in a dose-dependent manner with IC50 values of 1.4 +/- 0.8 nM (n = 8) and 0.9 +/- 0.7 nM (n = 7), respectively. Kd for factor VIIa binding to monocytes and Ki for FFR-FVIIa competing with factor VIIa were similar (11.4 +/- 0.8 pM and 10.6 +/- 1.1 pM, respectively), showing that FFR-FVIIa binds to tissue factor in the tenase complex with the same affinity as factor VIIa. Using platelets from volunteers before and after ingestion of aspirin (1.3 g), there were no significant differences in the IC50 values of FFR-FVIIa [after aspirin ingestion, the IC50 values were 1.7 +/- 0.9 nM (n = 8) for P-selectin expression, p = 0.37, and 1.4 +/- 1.3 nM (n = 7) for thrombin generation, p = 0.38]. This shows that aspirin treatment of platelets does not influence the inhibition of tissue factor initiated coagulation by FFR-FVIIa, probably because thrombin activation of platelets is not entirely dependent upon expression of thromboxane A2. PMID- 9364986 TI - Effects of plasma kallikrein specific inhibitor and active-site blocked factor VIIa on the pulmonary vascular injury induced by endotoxin in rats. AB - The acute respiratory distress syndrome (ARDS) is a serious complication of sepsis. To evaluate the role of the coagulation system in the pathogenesis of ARDS in sepsis, we examined the effects of the administration of a synthetic plasma kallikrein specific inhibitor (PKSI) and of active-site blocked factor VIIa (DEGR-VIIa) on the pulmonary vascular injury induced by E. coli endotoxin (ET) in rats. Administration of PKSI prevented the pulmonary vascular injury induced by ET as well as pulmonary histological changes in animals administered ET, but it did not affect the intravascular coagulation. The opposite effect was seen with DEGR-VIIa, which prevented the intravascular coagulation but not the pulmonary vascular injury. PKSI did not inhibit the activation of the complement system induced by ET leading to the activation of neutrophils. Findings suggest that PKSI may prevent the pulmonary vascular injury induced by ET by inhibiting kallikrein, which activates the neutrophils. The intrinsic pathway of coagulation may be more important than the extrinsic pathway in the pulmonary vascular injury produced by ET. PMID- 9364987 TI - Inhibition of thrombin generation in plasma by inhibitors of factor Xa. AB - A series of inhibitors of factor Xa (FXa) were investigated using the thrombin generation assay to evaluate the potency and specificity needed to efficiently block thrombin generation in activated human plasma. By inhibiting FXa the generation of thrombin in plasma is delayed and decreased. Inhibitor concentrations which cause 50 percent inhibition of thrombin generation (IC50) correlate in principle with the Ki values for inhibition of free FXa. Recombinant tick anticoagulant peptide (r-TAP) is able to inhibit thrombin generation with considerably low IC50 values of 49 nM and 37 nM for extrinsic and intrinsic activation, respectively. However, the potent synthetic, low molecular weight inhibitors of FXa (Ki values of about 20 nM) are less effective in inhibiting the generation of thrombin with IC50 values at micromolar concentrations. The overall effect of inhibitors of FXa in the thrombin generation assay was compared to that of thrombin inhibitors. On the basis of similar Ki values for the inhibition of the respective enzyme, synthetic FXa inhibitors are less effective than thrombin inhibitors. In contrast, the highly potent FXa inhibitor r-TAP causes a stronger reduction of the thrombin activity in plasma than the most potent thrombin inhibitor hirudin. PMID- 9364988 TI - Selection of S18326 as a new potent and selective boronic acid direct thrombin inhibitor. AB - Using enzymatic microassays, the potency of a series of new boroarginine tripeptides was determined versus thrombin and a panel of serine-proteases implicated in the coagulation and fibrinolysis pathways. The inhibition of the serine-protease complement factor I was also studied. Factor I regulates the alternate pathway of the complement and its inhibition appears to be responsible for the toxic effects of the orally available thrombin inhibitor Ac-D-Phe-Pro boroArg (DuP-714). The structure of the new boronic acid derivatives tested was modified from that of DuP-714 by replacing the proline in the P2 position by N cycloalkyl-glycine residues of increasing size (S18989: cyclopropyl; S18563: cyclobutyl; S18326: cyclopentyl; S18229: cyclohexyl). All compounds were found to be slow-tight binding inhibitors of thrombin versus purified human fibrinogen. Replacement of proline by N-cycloalkyl-glycines did not decrease the anti thrombin potency of the substances up to the cyclopentyl size and this result was confirmed by classical coagulation assays with human plasma in vitro. In contrast, the inhibitory activities of the four new boronic acids were found to be lower than those of DuP-714 versus plasmin, urokinase (u-PA), plasmatic kallikrein, activated protein C (aPC) and complement factor I. The cyclopentyl derivative S18326 is a slightly more active inhibitor of thrombin than DuP-714 (initial IC50 values 3.99 +/- 0.18 nM versus 4.73 +/- 0.27 nM, respectively). Moreover S18326 was identified as the most selective compound of the series with relative potencies being 2 to 29 fold higher than that of DuP-714 versus the panel of serine-proteases tested; the rank order of potency versus the other serine-proteases for S18326 was t-PA>kallikrein>aPC>factor I>plasmin>fXa>u-PA. These results indicate that the size of the thrombin hydrophobic pocket S2 is sufficient to accept larger residues than proline in the P2 position of Ac-D-Phe X-boroArg derivatives while this is not the case for other important serine proteases of the fibrinolysis, coagulation and complement pathways. The N cyclopentyl glycine containing derivative S 18326, which is the most potent and the most selective anti-thrombin compound of the series, currently undergoes major preclinical testing. PMID- 9364989 TI - Effect of oxidized low density lipoprotein on thrombomodulin expression by THP-1 cells. AB - We have investigated the effects of oxidized low density lipoproteins (oxidized LDL) on the expression of TM by THP-1 monocytic cells. TM antigen levels and its cofactor activity for thrombin-dependent protein C activation were increased by oxidized LDL and accompanied by an increase in TM mRNA levels. Incubation of THP 1 cells with 300 microg/ml oxidized LDL for 24 h resulted in an 80% increase of cellular TM antigen levels. Native LDL and acetylated LDL did not affect the TM expression by these cells. The resultant aqueous phase after extraction of oxidized LDL by chloroform/methanol increased the TM antigen levels as well as oxidized LDL. Phorbol 12-myristate 13-acetate (PMA) also increased the TM antigen level 2.1 times the control and was accompanied by the adhesion of cells to plastic dishes and increasing macrophage cell surface antigen CD14 levels. In contrast, oxidized LDL did not induce differentiation to the macrophage. The present results indicate that oxidized LDL increases cellular TM antigen without cellular differentiation and that up-regulation of TM by oxidized LDL in monocytes may have some implication in atherosclerosis. PMID- 9364990 TI - A fast and robust dual-label nonradioactive oligonucleotide ligation assay for detection of factor V Leiden. AB - Activated protein C resistance is in almost all cases caused by the factor V Leiden mutation (FV:R506Q). Due to the high prevalence and clinical significance of the mutation reliable methods suited for processing large sets of samples are in demand. We here present the oligonucleotide ligation assay (OLA) with lanthanide labeled oligonucleotides for the detection of FV Leiden. The assay is based on time resolved fluorescence measurement of lanthanide labeled oligonucleotides (DELFIA: Delayed Enhanced Lanthanide Fluorescence Immuno Assay) and on the specificity of T-4 DNA Ligase to join two adjacent oligonucleotides only when the two are complementary to the PCR template at the ligation junction. The Europium/Samarium fluorescence pattern is specific for each of the three genotypes (G/G, G/A, A/A) and clearly separates the three genotypes. By using a wildtype probe (Samarium labeled) and a mutant-specific probe (Europium labeled) simultaneously an internal control of the assay is included in each reaction. The assay is simple to perform, can be partly automated and is ideal for processing large sets of samples. PMID- 9364991 TI - Standardisation of protein S in plasma: calibration of the 1st International Standard. AB - An international collaborative study, involving 16 laboratories, was carried out to calibrate the 1st International Standard Protein S, plasma, for total and free Protein S antigen and for Protein S function. Potency estimates were calculated relative to locally collected fresh normal plasma pools. Estimates of total Protein S antigen showed good agreement between laboratories with inter laboratory geometric coefficient of variation (gcv%) of 8.8% and a mean value of 0.89 IU/ampoule. Estimates of free Protein S antigen calculated relative to total Protein S antigen in the fresh normal pools were more variable (gcv 26.8%) than estimates calculated relative to free Protein S antigen (gcv 15.3%); the latter comparison was used for calibration with a mean value of 0.89 IU/ampoule. Functional Protein S was estimated using commercial kits which gave an overall mean value of 0.92 IU/ampoule (gcv 14.0%). The 1st International Standard Protein S, plasma, (coded 93/590) was established in October 1995 with a single potency of 0.90 IU/ampoule for all three parameters. PMID- 9364992 TI - An in vivo model for the assessment of acute fibrinolytic capacity of the endothelium. AB - The effects on blood flow and plasma fibrinolytic and coagulation parameters of intraarterial substance P, an endothelium dependent vasodilator, and sodium nitroprusside, a control endothelium independent vasodilator, were studied in the human forearm circulation. At subsystemic locally active doses, both substance P (2-8 pmol/min) and sodium nitroprusside (2-8 microg/min) caused dose-dependent vasodilatation (p <0.001 for both) without affecting plasma concentrations of PAI 1, von Willebrand factor antigen or factor VIII:C activity. Substance P caused local increases in t-PA antigen and activity (p <0.001) in the infused arm while sodium nitroprusside did not. At higher doses, substance P increased blood flow and t-PA concentrations in the noninfused arm. We conclude that brief, locally active and subsystemic infusions of intraarterial substance P cause a rapid and substantial local release of t-PA which appear to act via a flow and nitric oxide independent mechanism. This model should provide a useful and selective method of assessing the in vivo capacity of the forearm endothelium to release t-PA acutely. PMID- 9364993 TI - Inhibition of mannose receptor-mediated clearance of tissue-type plasminogen activator (t-PA) by dextran: a new explanation for its antithrombotic effect. AB - Dextran is used during surgery as a prophylactic agent to prevent deep venous thrombosis. Recently it has been shown that dextran increases t-PA plasma concentrations in patients. As dextran is a potential ligand for the mannose receptor, we studied whether this glucose-polymer would be able to inhibit mannose receptor-mediated clearance of t-PA. In this report we show that dextran 40 and dextran 70 were able to inhibit t-PA binding to the isolated human mannose receptor (IC50 14 and 4 mg/ml, respectively). Both glucose-polymers inhibited mannose receptor-mediated t-PA degradation by human monocyte-derived macrophages in vitro (IC50 7 and 2 mg/ml, respectively). The alpha2-macroglobulin receptor/low density lipoprotein receptor-related protein (LRP)-mediated t-PA degradation by the macrophages was not affected by dextran. During and after a 45 min infusion of dextran 70 (Macrodex) in rats, in plasma endogenous t-PA concentrations increased to 162 +/- 33% and 122 +/- 35% respectively. The plasma clearance of a bolus injection of exogenous t-PA was decreased by 33 +/- 9% in the same rats. We conclude that dextran inhibits mannose receptor-mediated t-PA clearance. The inhibition of t-PA clearance during dextran infusion results in increased endogenous t-PA plasma concentrations. Increased t-PA concentrations present during thrombus formation are known to increase thrombus lysability. Thus the inhibition of t-PA clearance can contribute to the antithrombotic effect of dextran. PMID- 9364994 TI - The regulation of platelet aggregation in vitro by interleukin-1beta and tumor necrosis factor-alpha: changes in pregnancy and in pre-eclampsia. AB - Platelet activation occurs in early pregnancy in women at risk of developing pre eclampsia. Cytokines have been implicated in the pathogenesis of pre-eclampsia, so we determined the effects of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) on the in vitro aggregation of human platelets. IL-1beta increased aggregation of platelets from non-pregnant and pre-eclamptic women, and inhibited the aggregation of platelets from normal pregnant women. This latter effect was linked to a diminished P-selectin expression on ADP-stimulated whole blood platelets in normal pregnant women (p = 0.011). Platelet aggregation in response to ADP was found to be inhibited after preincubation with TNF-alpha in non-pregnant (38%, p = 0.01) and in normal pregnant women (54%, p = 0.001) and not affected in pre-eclamptic women. The inhibitory effects of TNF-alpha were mediated through the P75 receptor for TNF-alpha. PMID- 9364995 TI - Sensitive measurement of thrombopoietin by a monoclonal antibody based sandwich enzyme-linked immunosorbent assay. AB - In this report a sensitive enzyme-linked immunosorbent assay (ELISA) for the measurement of plasma thrombopoietin (Tpo) is described that is solely based on monoclonal antibodies (MoAbs). The assay has an intra and inter-assay variance of 5-7% and 7-13%, respectively. Native and recombinant human Tpo (rhTpo) were recognized equally well, no cross reactivity with other cytokines was found and rhTpo added to plasma and serum was completely recovered. With the ELISA, Tpo concentrations in EDTA-anticoagulated plasma of all controls (n = 193) could be determined, since the limit of detection (2 +/- 0.8 A.U./ml, mean +/- sd) was lower than the concentration found in controls (11 +/- 8 A.U./ml, mean +/- sd; 2.5th-97.5th percentile: 4-32 A.U./ml). Tpo levels in serum were on average 3.4 times higher than in plasma. We showed in vivo that Tpo is bound by platelets, as in thrombocytopenic patients (n = 5) a platelet transfusion immediately led to a drop in plasma Tpo level, whereas in patients receiving chemotherapy the induced thrombocytopenia was followed by a rise in plasma Tpo levels. In summary, these results indicate that this ELISA is a reliable tool for Tpo measurements and is applicable for large scale studies. PMID- 9364996 TI - Partial blockade of nitric oxide synthase blunts the exercise-induced increase of von Willebrand factor antigen and of factor VIII in man. AB - BACKGROUND: Until now the effects of beta-adrenergic agonists have largely been ascribed to their ability to induce intracellular formation of cyclic adenosine monophosphate. Recently evidence has been accumulating that at least some beta1 and beta2-adrenoceptor effects may be mediated by nitric oxide (NO). Based on these studies, we hypothesized that the beta-adrenoceptor mediated increase of von Willebrand factor and factor VIII-activity (FVIII:C) in plasma during exercise, is caused by an NO-dependent mechanism. METHODS: Thirteen young healthy subjects finished an exhaustive bicycle exercise protocol while they were infused placebo or the NO-synthase inhibitor N-monomethyl-L-arginine (L-NMMA) on two separate days in a randomized, double blind cross-over design. FINDINGS: During exercise systemic haemodynamic changes were parallel in both treatment periods, but L-NMMA caused a partial inhibition of NO-synthase as evidenced by a 30% decrease in exhaled NO. The workload capacities were not different during L-NMMA or placebo infusion. However, under placebo treatment exercise increased vWF-Ag by a maximum of 61% (CI: 43-84; p = 0.002) and FVIII:C by 44% (CI: 31-59; p = 0.001), which was significantly attenuated when subjects were treated with L-NMMA (p <0.05): under L-NMMA treatment vWF-Ag increased by only 25% (CI: 5-51; p = 0.001) and FVIII:C by 12% (CI: 6-39; p = 0.001). INTERPRETATION: Partial blockade of NO-synthase with L-NMMA blunts the exercise-induced increase in vWF-Ag and FVIII:C. Our trial points to a role of endogenous NO-generation in the beta2 adrenergic increase in vWF/FVIII. Thus, we propose that physiologic processes which are induced by systemic beta2-adrenoceptor stimulation may at least partly be mediated by NO. PMID- 9364997 TI - von Willebrand factor activity detected in a monoclonal antibody-based ELISA: an alternative to the ristocetin cofactor platelet agglutination assay for diagnostic use. AB - The monoclonal antibody RFF-VIII:R/1 recognises an epitope on von Willebrand factor involved in its interaction with GPIb alpha. A two-site, solid phase ELISA has been established using RFF-VIII:R/1 as the solid-phase, capture antibody and an enzyme-conjugated, polyclonal antibody to human VWF, which provides an assay for VWF functional activity with a detection limit of 0.5 U/dl VWF and an interassay %CV < 10. Plasma from 192 VWD patients (48 studied retrospectively; 144 prospectively) showed VWF levels of < 50 U/dl in type 1 patients (n = 156), < 25 U/dl in type 2A (n = 26) and < 35 U/dl in type 2B (n = 8) which, in type 1 and 2A patients, correlated with RiCoF activity (r > or = 0.82). In plasma from patients with type 1 VWD values of VWF in the Mab-based ELISA were similar to levels of VWF:Ag measured in a polyclonal antibody-based ELISA (r > or = 0.87) but were significantly lower than VWF:Ag in type 2A and 2B plasmas (p < or = 0.0005), allowing discrimination of variant VWD. The Mab-based ELISA has advantages of sensitivity and reproducibility over the RiCoF assay to measure VWF activity and can be used to analyse stored samples. In conjunction with an ELISA for VWF:Ag and VWF multimer analysis, it provides a reliable method for the laboratory diagnosis of VWD. PMID- 9364998 TI - Comparison of enoxaparin, hirulog, and heparin as adjunctive antithrombotic therapy during thrombolysis with rtPA in the stenosed canine coronary artery. AB - A canine model of electrolytic injury-induced coronary artery thrombosis and rtPA induced thrombolysis was used to evaluate the relative antithrombotic efficacy of enoxaparin (a low molecular weight heparin), conventional therapy (heparin or heparin plus aspirin), and hirulog (a direct thrombin inhibitor), when used as adjunctive therapy during thrombolysis. After 60 min of clot aging, adjunctive therapy was begun at doses which elevated APTT approximately 2-fold over baseline. Fifteen minutes after the start of adjunctive therapy, recombinant tissue plasminogen activator (rtPA) was administered (100 microg/kg i.v. bolus + 20 microg/kg/min for 60 min). Adjunctive therapy continued for 1 h after termination of rtPA and blood flow was monitored for two additional hours. Enoxaparin (1 mg/kg i.v. bolus + 30 microg/kg/min, n = 10 for each treatment group) was the only adjunctive treatment that significantly increased the total minutes of flow (143 +/- 25 min out of a possible 240 min, vs 54 +/- 25 min for vehicle, p <0.05) and decreased thrombus mass (6.0 +/- 1.3 mg vs 11.8 +/- 3.2 mg for vehicle). Although hirulog (2 mg/kg i.v. bolus + 40 microg/kg/min) did not significantly increase the minutes of flow (120 +/- 27 min, p <0.06) or decrease thrombus mass (8.7 +/- 1.7 mg) compared to vehicle, these values were not significantly different than those measured in the enoxaparin group. However, the results with hirulog were achieved at the expense of a significantly greater increase in template bleeding time than that measured during enoxaparin treatment. Minutes of flow for heparin (50 U/kg i.v. bolus + 0.6 U/kg/min) and heparin plus aspirin (5 mg/kg i.v. bolus) were 69 +/- 20 and 60 +/- 23 min, respectively; thrombus masses were 8.2 +/- 1.3 and 7.3 +/- 1.0 mg, respectively. In summary, enoxaparin was more effective than conventional therapy in this model in terms of vessel patency and thrombus mass, and was as effective as hirulog, at least at a dose of hirulog that only modestly impaired hemostasis. Therefore, enoxaparin may prove to be a safe and effective alternative agent for adjunctive therapy during thrombolysis with rtPA. PMID- 9364999 TI - The importance of enzyme inhibition kinetics for the effect of thrombin inhibitors in a rat model of arterial thrombosis. AB - The relation between the antithrombotic effect in vivo, and the inhibition constant (Ki) and the association rate constant (k(on)) in vitro was investigated for eight different thrombin inhibitors. The carotid arteries of anaesthetized rats were exposed to FeCl3 for 1 h, and the thrombus size was determined from the amount of incorporated 125I-fibrinogen. The thrombin inhibitors were given intravenously, and complete concentration- and/or dose-response curves were constructed. Despite a 50,000-fold difference between the Ki-values comparable plasma concentrations of hirudin and melagatran were needed (0.14 and 0.12 micromol l(-1), respectively) to obtain a 50% antithrombotic effect (IC50) in vivo. In contrast, there was a comparable in vitro (Ki-value) and in vivo (IC50) potency ratio for melagatran and inogatran, respectively. These results can be explained by the concentration of thrombin in the thrombus and improved inhibition by the low-molecular-weight compounds. For all eight thrombin inhibitors tested, there was an inverse relationship between k(on)-values in vitro and the slope of the dose response curves in vivo. Inhibitors with k(on) values of < 1 x 10(7) M(-1) s(-1) gave steep dose response curves with a Hill coefficient > 1. The association time for inhibition of thrombin for slow-binding inhibitors will be too long to give effective antithrombotic effects at low plasma concentrations, but at increasing concentrations the association time will decrease, resulting in a steeper dose-response curve and thereby a more narrow therapeutic interval. PMID- 9365000 TI - Different distribution of the double mutant "T833C/68 bp insertion" in cystathionine beta-synthase gene in Northern and Southern Italian populations. PMID- 9365001 TI - 4G/5G polymorphism in the promoter region of the PAI-1 gene is not a risk factor for familial myocardial infarction in subjects over 45 years. PMID- 9365002 TI - Detection of factor V Leiden using ASO (allele specific oligonucleotide) PMID- 9365003 TI - Prospective evaluation of the prevalence of factor V Leiden mutation in portal or hepatic vein thrombosis. PMID- 9365004 TI - Factor V Leiden mutation in women with idiopathic pulmonary embolism. PMID- 9365006 TI - The clinical utility of a rapid bedside D-dimer assay for screening of deep vein thrombosis following orthopaedic surgery. PMID- 9365005 TI - Double treatment of severe hepatic veno-occlusive disease after allogeneic peripheral blood progenitor cell transplantation with recombinant tissue plasminogen activator. PMID- 9365007 TI - Impaired platelet aggregation and abnormal activation of GPIIb-IIIa. PMID- 9365008 TI - Another variant pattern of intron 22 inversion in the factor VIII gene seen in a severe haemophilia A patient. PMID- 9365009 TI - Acute increases in forebrain blood flow during altering responses in conscious rabbits. AB - We have previously shown that alerting responses (documented by appearance of theta rhythm in the hippocampal EEG) are associated with a characteristically timed acute vasoconstriction in the ear artery bed of the conscious rabbit. We have now determined what happens to forebrain blood flow (Doppler probe chronically implanted around the internal carotid artery) during similar alerting responses in conscious rabbits, comparing forebrain flow to simultaneously measured ear flow. During an alerting response, forebrain flow increased by 31 +/ 8% of baseline (n = 6, P < 0.01), with the increase commencing within 1 s of the stimulus, at approximately the same time as the decrease in ear flow. Arterial pressure increased from 77 +/- 3 to 81 +/- 3 mmHg (P < 0.01), so that internal carotid conductance increased from 0.17 +/- 0.02 to 0.20 +/- 0.02 kHz/mmHg (P < 0.01). During a 1 h continuous recording period in the laboratory there was a negative correlation between forebrain and skin flow, with the Pearson coefficient in individual rabbits ranging from -0.18 to -0.62 (n = 6, all correlations P < 0.01). During this period, forebrain blood flow was just as variable, from second to second, as distal aortic flow, but not as variable as ear blood flow. Our study thus demonstrates that alerting responses in rabbits are associated with rapid increases in cerebral vascular conductance. We believe that this is the first demonstration of this phenomenon in the conscious experimental animal. PMID- 9365010 TI - Evaluation of opioid receptor subtype antagonist effects in the ventral tegmental area upon food intake under deprivation, glucoprivic and palatable conditions. AB - Opioid receptor subtype antagonists differentially alter food intake under deprivation (24 h), glucoprivic (2-deoxy-D-glucose, 500 mg/kg, i.p.) or palatable (10% sucrose) conditions with mu (beta-funaltrexamine) and kappa (nor binaltorphamine), but not delta1 ([D-Ala2,Leu5,Cys6]enkephalin) opioid antagonists reducing each form of intake following ventricular microinjection. Both mu and kappa opioid antagonists microinjected into either the hypothalamic paraventricular nucleus or the nucleus accumbens reduce intake under deprivation and glucoprivic conditions. Palatable intake is reduced by both antagonists in the paraventricular nucleus, but only mu antagonists are active in the accumbens. Food intake is stimulated by mu and delta, but not kappa, opioid agonists microinjected into the ventral tegmental area. The present study examined whether food intake under either deprivation, glucoprivic or palatable conditions was altered by bilateral administration of general (naltrexone), mu, kappa, delta1 or delta2 (naltrindole isothiocyanate) opioid antagonists into the ventral tegmental area. Deprivation (24 h)-induced feeding was significantly reduced by high (50 microg), but not lower (10-20 microg) doses of naltrexone (21%), and by delta2 (4 microg, 19%) antagonism in the ventral tegmental area. 2-Deoxy-D-glucose (500 mg/kg, i.p.)-induced hyperphagia was significantly reduced by high (50 microg), but not lower (20 microg) doses of naltrexone (64%), and by delta2 (4 microg, 27%) antagonism in the ventral tegmental area. Sucrose (10%) intake was significantly reduced by naltrexone (20-50 microg, 25-39%) and delta2 (4 microg, 25%) antagonism in the ventral tegmental area. Neither mu, kappa nor delta1 antagonists were effective in reducing any form of intake following microinjection into the ventral tegmental area. These data indicate that the ventral tegmental area plays a relatively minor role in the elicitation of these forms of food intake, and that delta2, rather than mu, kappa or delta1 opioid receptors appear responsible for mediation of these forms of intake by this nucleus. PMID- 9365011 TI - Progressive impairment of brain oxidative metabolism reversed by reperfusion following middle cerebral artery occlusion in anaesthetized baboons. AB - A better understanding of the temporospatial evolution of ischaemic brain tissue towards necrosis would be of crucial value to establish and validate therapeutic strategies for stroke in man. By means of sequential positron emission tomographic (PET) studies performed through the acute to the chronic stages of infarction, we addressed the question of the effect of 6 h temporary occlusion of the middle cerebral artery (MCAO) on the evolution of the volume of severely hypometabolic tissue in anaesthetized baboons and compared it to that reported previously in permanently occluded baboons. Thirteen anaesthetized baboons underwent serial PET (15O steady-state technique) examinations before and 1, 4, 7, 24-48 h and 15-62 days following transorbital MCAO. Reperfusion, at 6 h post occlusion, was assessed by Doppler sonography and cerebral blood flow (CBF) values after clip removal. In each baboon, the infarct volume was calculated by standard histological procedures 20-91 days after MCAO. The severely hypometabolic tissue volume, as defined by a threshold of oxidative metabolism, showed a progressive increase for up to 24-48 h in a not dissimilar manner to that found in baboons with permanent occlusion. However, these hypometabolic volumes regressed in the chronic stage (p < 0.05). Permanent and temporary occluded baboons, when taken together, showed a highly significant relationship between histological and chronic hypometabolic volumes (r = 0.84; p < 0.001). Moreover, the final hypometabolic volume where cerebral metabolic rate of oxygen (CMRO2) was below 40% of contralateral metabolism corresponded well to that of histological infarction volume. We conclude that, in anaesthetized baboons, restoration of blood flow will reverse (even if not immediately) the progressive derangement of metabolism after MCAO and markedly limit the final volume of consolidated infarction.) PMID- 9365012 TI - The characteristics of basolateral nucleoside transport in the perfused sheep choroid plexus and the effect of nitric oxide inhibition on these processes. AB - The single pass paired dilution technique was used to measure the uptake of nucleosides across the basolateral face of the isolated in situ perfused sheep choroid plexus (CP). The uptake of labelled adenosine and guanosine into the CP was large (approximately 35%) whereas that of thymidine was less (approximately 15%). The addition of 0.5 mM unlabelled adenosine to the perfusate inhibited the uptake of labelled adenosine by 66%, guanosine by 100% and that of thymidine by 50%, whereas the addition of 0.5 mM unlabelled thymidine caused complete self inhibition. The backflux of adenosine was very small which may indicate a high rate of cellular metabolism or a flux into cerebrospinal fluid (CSF). The addition of 0.5 mM unlabelled adenosine did not alter the backflux of adenosine, but increased that of guanosine and thymidine. The entry of radioactivity derived from adenosine across the apical side of the CP cells into the newly formed CSF was determined as a 'CSF uptake index' relative to [14C]butanol and found to be about 25%; however, HPLC analysis revealed that the majority of this activity was hypoxanthine, and not adenosine. The complete inhibition of nitric oxide synthase caused a significant reduction in adenosine uptake into the CP and an increase in backflux for this molecule. It would appear that the uptake for adenosine by the CP is governed by the rate of cellular metabolism and not by the rate of transport into the cells of the choroid plexus whereas for guanosine and thymidine, transport is of greater importance. PMID- 9365013 TI - Tolerance to the neurotoxic effect of methamphetamine in rats behaviorally sensitized to methamphetamine or amphetamine. AB - A series of experiments was conducted to examine whether rats behaviorally sensitized to methamphetamine (MA) would show supersensitivity or tolerance to the MA-induced neurotoxic effects on dopaminergic and serotonergic nerve terminals in the striatum (ST), nucleus accumbens (NA) and medial frontal cortex (MFC). Moderate to high doses of MA (3, 4 and 5 mg HCl salt/kg, s.c., at 2 h intervals, four injections) dose-relatedly decreased the contents of dopamine (DA), dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in ST, and the content of 5-HIAA in NA and that of 5-HT in MFC. These neurotoxic effects in ST were significantly attenuated in rats behaviorally sensitized to MA (4 mg HCl salt/kg, s.c., for 10 days). To examine the possibility that the attenuation in the toxic effects in sensitized rats was due to an accelerated metabolism from MA to amphetamine (AMPH), a high dose of MA (5 mg HCl salt/kg, s.c., at 2 h intervals, four injections) was administered to rats behaviorally sensitized to AMPH (4 mg HCl salt/kg, s.c., for 10 days). It was revealed that the MA-induced decrease in the striatal contents of DOPAC, homovanillic acid (HVA), 5-HT and 5-HIAA were attenuated in rats behaviorally sensitized to AMPH. The MA-induced decrease in the striatal DA content tended to be attenuated in AMPH-sensitized rats. These data suggest that rats behaviorally sensitized to MA or AMPH develop tolerance to MA-induced striatal dopaminergic and serotonergic neurotoxicity. It is speculated that the mechanism of tolerance might be mediated by an altered central response rather than peripheral metabolism. PMID- 9365015 TI - Profile of neuronal excitation following selective activation of the neurokinin-1 receptor in rat deep dorsal horn in vitro. AB - The excitatory actions of the selective neurokinin-1 receptor (NK1R) agonist [Sar9,Met(O2)11]substance P (SP) were tested on a sample (n = 50) of deep dorsal horn neurones in the isolated and hemisected young rat spinal cord. Superfusion of the NK1R agonist (2 microM) elicited a prolonged membrane depolarisation (6.6 +/- 0.5 mV) and an increase in action potential firing in 41/50 (82%) neurones. These [Sar9,Met(O2)11]SP-induced depolarisations were attenuated by the selective NK1R antagonist GR82334 (1 microM). An increased neuronal excitability after [Sar9,Met(O2)11]SP application was indicated by an augmented spike frequency generated in response to long duration, step depolarisations. In order to assess whether a direct excitatory action existed, [Sar9,Met(O2)11]SP was re-tested on a sample of TTX-treated neurones (n = 14). The majority (9/14) retained agonist sensitivity although the amplitude of the depolarisation was reduced to 48% of the control value. A sample of neurones (n = 7) that responded to the NK1R agonist were morphologically characterised after filling with the intracellular dye, biocytin. Dorsal dendrites that clearly penetrated lamina II and that could receive a direct C-afferent input, were identified in only 2/7 neurones. These electrophysiological and neuroanatomical data demonstrate that deep dorsal horn neurones possess functional NK1Rs. The implications of the existence of these NK1Rs in the context of spinal somatosensory systems and SP is considered. PMID- 9365014 TI - Cerebral 6-[18F]fluoro-L-DOPA uptake in rhesus monkey: pharmacological influence of aromatic amino acid decarboxylase (AAAD) and catechol-O-methyltransferase (COMT) inhibition. AB - FDOPA/PET scans were performed in one rhesus monkey to study the influence of three catechol-O-methyltransferase (COMT) inhibitors (CGP 28014, OR-611 and Ro 40 7592) on FDOPA pharmacokinetics. COMT inhibitors were administered in combination with carbidopa, a peripherally acting inhibitor of the aromatic amino acid decarboxylase (AAAD). FDOPA was administered intravenously and its metabolic fate in plasma was determined using an HPLC system with an on-line gamma-gamma coincidence detector. Cerebral tracer uptake was assessed in the striatum and in a non-dopaminergic brain region (occipital cortex). In the periphery, the pharmacokinetic efficiency of FDOPA was increased due to the combined inhibition of COMT and AAAD activity. All three COMT inhibitors reduced the FDOPA methylation rate constant in plasma, with complete suppression obtained in the case of Ro 40-7592. In the brain, specific 18F radioactivity (striatal minus brain reference radioactivity) increased as a result of the increase in FDOPA plasma availability following the administration of COMT and AAAD inhibitors. We established a significant linear correlation between striatal radioactivity and FDOPA plasma levels (r = 0.924 +/- 0.048, P < 0.0001 for total striatal and r = 0.948 +/- 0.054, P < 0.0001 for specific striatal radioactivity). Using plasma FDOPA radioactivity as input, we found that the striatal FDOPA uptake rate constant KiFD was not changed by any of the inhibitors. Thus, the enhancement of striatal radioactivity after application of enzyme inhibitors is a consequence of the increase in plasma FDOPA that becomes available for conversion to fluorodopamine in the striatal dopaminergic nerve terminals. By contrast, using the radioactivity in a non-dopaminergic region (cortex) as input, we found that the striatal FDOPA uptake rate constant Ki(ref) was significantly (P < 0.0001) increased following pretreatment with COMT inhibitors. Our analysis demonstrated that Ki(ref) and the 3-OMFD contribution to the cerebral radioactivity were inversely correlated. PMID- 9365016 TI - Delta9-tetrahydrocannabinol stimulates glucose utilization in C6 glioma cells. AB - The present work was undertaken to study the metabolic response of C6 glioma cells to physiologically relevant doses of delta9-tetrahydrocannabinol (THC), the major active component of marijuana. At those concentrations (i.e. nanomolar range), THC produced a dose-dependent increase in the rates of glucose oxidation to CO2 and glucose incorporation into phospholipids and glycogen. The THC-induced stimulation of glucose utilization was (i) dose-dependent up to 100 nM THC, (ii) mimicked by the synthetic cannabinoid HU-210, and (iii) prevented by pertussis toxin and the CB1 receptor antagonist SR141716A. In contrast to THC, forskolin markedly depressed CO2 production, phospholipid synthesis and glycogen synthesis from glucose. The forskolin-induced inhibition of glucose utilization was (i) mimicked by dibutyryl-cAMP, and (ii) prevented by THC, HU-210 and H-7, an inhibitor of the cAMP-dependent protein kinase. Likewise, THC was able to antagonize in part the forskolin-induced elevation of intracellular cAMP concentration, and this antagonistic effect was prevented by SR141716A. However, THC per se did not affect basal cAMP concentration. Results thus indicate that physiologically relevant doses of THC stimulate glucose metabolism in C6 glioma cells through a cannabinoid receptor-mediated process. Although cannabinoid receptors may be coupled to inhibition of adenylyl cyclase in C6 glioma cells, this does not seem to be the mechanism involved in the THC-induced stimulation of glucose metabolism. PMID- 9365017 TI - Functional characterization of the H-current in SCN neurons in subjective day and night: a whole-cell patch-clamp study in acutely prepared brain slices. AB - Neurons of the rat suprachiasmatic nucleus (SCN) exhibit a circadian rhythm in spontaneous firing rate. In this whole-cell patch-clamp study in slices, we examined the possibility that H-current (IH) contributes to the spontaneous firing rate of SCN neurons. Most of our experiments were performed during the subjective day, because this is the time epoch during which one would expect the largest excitatory effect of IH if it were to fluctuate in a circadian rhythm. Current-clamp experiments showed that blockade of IH by Cs+ (1 mM) did not influence the spontaneous firing rate and resting membrane potential. Voltage clamp experiments revealed that IH, when activated at the resting membrane potential, is probably too small in magnitude and too slow in activation to make a significant contribution to the spontaneous firing rate. Both results suggest that IH does not significantly contribute to the spontaneous firing of SCN neurons. In addition, we investigated whether the kinetics and voltage dependence of IH were modulated in a circadian manner. However, no substantial day-night differences in IH were found. We conclude that IH, as recorded in whole-cell mode, does not contribute significantly to spontaneous firing in most SCN neurons and that this current, is more likely to be involved in 'rescuing' SCN neurons from large and long-lasting hyperpolarizations by depolarizing the membrane. PMID- 9365018 TI - Postischemic accumulation of lipid peroxidation products in the rat brain: immunohistochemical detection of 4-hydroxy-2-nonenal modified proteins. AB - We report an immunohistochemical study on the distribution and alterations of 4 hydroxy-2-nonenal (HNE)-modified proteins, an indicator of lipid peroxidation, in the rat brain after 3 h of middle cerebral artery (MCA) occlusion followed by reperfusion. HNE immunoreactivity was not observed in intact neurons, but it appeared in some shrunken neurons within the infarcted zone at 3 h after reperfusion. The number of HNE-positive neurons increased with the spread of the infarcted area. The pyramidal neurons in the third layer of the frontoparietal cortex were HNE-positive and the intensity of their HNE immunoreactivity was highest at 24 h after reperfusion. At 48 h, HNE-positive neurons were observed in the medial part of the striatum, the lateral side of the frontoparietal cortex, and at the boundary between the infarcted and noninfarcted zones. In addition, strong HNE immunoreactivity was seen in microglia (identified by OX-42 immunostaining). This method seems to be useful to follow the progress of lipid peroxidation at the cellular level after ischemic injury. PMID- 9365019 TI - Source of corticotropin-releasing hormone-like innervation of the adrenal glands of fetal and postnatal sheep. AB - In pre- and postnatal sheep the irregularly shaped adrenal corticomedullary interface is innervated by corticotropin-releasing hormone (CRH)-like beaded fibers. Since CRH-like staining is also seen in the splanchnic nerves, we examined the intermediolateral sympathetic columns (ISC) of the thoracic (T) spinal cords (segments 5-13) of 12 pre- and postnatal sheep for CRH-like immunocytochemical reactivity and in a subset of fetuses, fluorogold immunoreactivity after fluorogold injection to the left adrenal medulla. All animals had CRH-like immunopositive neurons in the ISC from all thoracic segments. The number of CRH-like positive neurons per thoracic segment did not change either from anterior to posterior within groups nor were there differences between groups. Fluorogold immunopositive neurons occurred in the ISC of all injected animals from T5 to T13. Upon double immunostaining, some ISC CRH-like immunopositive neurons also demonstrated fluorogold immunopositivity. Taken together, these studies indicate that there are CRH-like immunopositive neurons in the ISC of pre- and postnatal sheep and that some of these CRH-like immunopositive neurons innervate the adrenal medulla. PMID- 9365021 TI - Spatial properties and interhemispheric differences of the sensory hand cortical representation: a neuromagnetic study. AB - We performed a neuromagnetic investigation of the sensory hand cortical representation in the two hemispheres of 20 healthy volunteers. The localizations within the brain hemispheres of the cortical Equivalent Current Dipoles (ECDs) activated with the shortest latencies (N20 m and P30 m components) by separate stimulation of contralateral median nerve, thumb and little finger were analysed. The ECD spatial coordinates were in agreement with the known somatotopy of the sensory homunculus: little finger more medial and posterior, thumb more lateral and anterior, median nerve in-between. By considering the ECDs to thumb and little finger stimulation the boundaries of the hand cortical representation in primary sensory cortex, the 'hand extension' was evaluated as the distance between the two. This parameter was similar on the two hemispheres, the 'hand extension' being 17 mm and 12 mm for N20 m and P30 m components, respectively, with a standard deviation of 5 mm. We provide for the first time the ECDs localization of left and right median nerve, thumb and little finger, as well as the 'hand extension' values, and their interhemispheric differences as a normative data set describing the organization of primary sensory cortical areas reserved to the hand in the healthy population. This approach permits objective measurements of absolute values, as well as of interhemispheric differences, of the sensory hand area following a monohemispheric lesion as well as to non invasively follow-up its reorganization during clinical recovery. PMID- 9365020 TI - Prostaglandin E2 may induce hyperthermia through EP1 receptor in the anterior wall of the third ventricle and neighboring preoptic regions. AB - We have previously reported that intracerebroventricular injection of prostaglandin E2 (PGE2) induces hyperthermia possibly through EP1 receptors in the rat. In the present study, to determine the sites in the brain where PGE2 induces hyperthermia through EP1 receptors, we microinjected an EP1 receptor agonist, 17-phenyl-omega-trinor PGE2 (17-Ph-PGE2, 100 ng) into different sites in the rat brain and observed the colonic temperature (Tco) for 2 h in a 23 +/- 1 degrees C environment. Responsive sites where 17-Ph-PGE2 (100 ng) produced a rise in the Tco of more than 1.1 degrees C within 60 min after injection were found in the medial preoptic area, the subchiasmatic portion of the median preoptic nucleus, the anterior wall of the third ventricle (A3V) and the ventral portion of the diagonal band of Broca. Among these sites, the A3V was the most responsive. In contrast, microinjection of neither butaprost (an EP2 agonist, 100 ng) nor M&B28767 (an EP3 agonist, 100 ng) into these four sites had any effect on the Tco. Intracerebroventricular pretreatment with SC-19220 (an EP1 antagonist, 100 microg) inhibited the rise in the Tco which was induced by microinjection of PGE2 (50 ng) into the A3V. These results thus suggest that PGE2 induces hyperthermia by stimulating EP1 receptors in the A3V and the neighboring preoptic region. PMID- 9365022 TI - Axon terminals containing PACAP- and VIP-immunoreactivity form synapses with CRF immunoreactive neurons in the dorsolateral division of the bed nucleus of the stria terminalis in the rat. AB - The bed nucleus of the stria terminalis (BST) is a highly heterogeneous forebrain structure, within which the median and lateral BST play distinct functional roles. The medial BST (BSTM) is thought to be related to sexual behavior, while the lateral BST (BSTL) may have a stress-related function. In the human brain, the BST shows marked sexual dimorphism in the distribution of vasoactive intestinal polypeptide (VIP) immunoreactive fibers and also contains a very high concentration of pituitary adenylate cyclase activating polypeptide (PACAP) immunoreactivity (ir). Using immunohistochemistry (IHC) to examine the rat brain, the present study found that both VIP and PACAP containing afferent fibers are abundant in the BSTLd (dorsolateral division of BST), but not in the BSTM. IHC did not reveal any apparent difference between the sexes in the size of distribution of either immunoreactivity. Double staining IHC showed that axonal terminals of both VIP and PACAP neurons were in close proximity to dendrites or perikarya of corticotropin releasing factor (CRF) neurons. At the electron microscopic level IHC revealed the presence of axodendritic or axosomatic synapses between VIP-ir and PACAP-ir axon terminals and CRF-ir neurons. Although the origin of PACAP-ir fibers in the BSTLd remains to be determined, these morphological findings suggest that PACAP and VIP regulate the activity of CRF neurons in the BSTLd as neurotransmitters or neuromodulators. PMID- 9365023 TI - Aldosterone up-regulates mRNA for the alpha3 and beta1 isoforms of (Na,K)-ATPase in several brain regions from adrenalectomized rats. AB - In physiological doses, mineralocorticoids (MC) normalize the high salt intake developed after adrenalectomy. We have studied whether this effect of MC is accompanied by changes in the mRNA of neuronal alpha3 and beta1 subunits of the (Na,K)-ATPase because this enzyme could by a mediator of MC action in target cells. We employed [35S]oligonucleotide probes for the mentioned subunits hybridized to brain sections from adrenalectomized rats and adrenalectomized rats receiving aldosterone (ALDO) during 4 days. Using t-test statistics to measure differences in mean levels of grain density, and the Kolmogorov-Smirnov non parametric test applied to frequency histograms, we showed that ALDO increased the alpha3 subunit mRNA in the septum medialis, preoptic area medialis, caudate putamen, periventricular gray substance, amygdala lateralis, hippocampal subfields CA1 to CA4 and the gyrus dentatus. Significant increases for the beta1 subunit mRNA were found in periventricular gray substance, the CA1-CA4 hippocampal subfields and gyrus dentatus. Therefore, the salt-suppression effect of MC was accompanied by coordinate increases in (Na,K)-ATPase alpha3 and beta1 subunit mRNA in the hippocampus, gyrus dentatus and periventricular gray substance, whereas in other regions the stimulatory effect was exclusive of the alpha3 subunit mRNA only. The results suggest that the enzyme could be a target of ALDO action not only in areas related to salt appetite control (amygdala, preoptic area) but also in brain regions subserving other functions of the MC. PMID- 9365024 TI - Putrescine-modified catalase with preserved enzymatic activity exhibits increased permeability at the blood-nerve and blood-brain barriers. AB - Much evidence exists in support of the hypothesis that free radicals contribute to the pathogenesis of several neurodegenerative disorders and that mechanisms of free radical generation occur both intracellularly and extracellularly. Previous studies in this laboratory have shown that covalent modification of growth factors and antioxidant enzymes with the naturally occurring polyamine, putrescine, increases their permeability at the blood-nerve and blood-brain barriers (BNB and BBB), but does not significantly inhibit bioactivity. Furthermore, putrescine-modified superoxide dismutase (SOD) was shown to reduce neurodegeneration in a rat model of global cerebral ischemia. The purpose of the present study was to modify the antioxidant enzyme, catalase (CAT), with putrescine (PUT) at carboxylic acid groups whose ionization, and hence reactivity, was controlled with pH and investigate the effects on permeability and enzymatic activity. Modification of CAT with PUT increased its permeability 2 3-fold and preserved 67% of its enzymatic activity compared to native CAT and 137% compared to lyophilized CAT. The results of this study indicate that modification of CAT with putrescine increases its permeability while preserving enzymatic activity. PUT-SOD administered in combination with PUT-CAT may eliminate both the superoxide radical and the H2O2 produced from the dismutation of superoxide, respectively, and thus prevent the formation of hydroxyl radicals. This combination may exhibit increased neuroprotective effects, compared to native enzymes, following systemic administration for the treatment of free radical associated neurodegenerative disorders. PMID- 9365025 TI - Prior brain injury protects death from local anaesthetic-induced convulsion. AB - Minor brain injury was inflicted with a small hypodermic needle at four sites from the scalp 7 days before the production of convulsion by i.p. injection of 100 mg/kg lidocaine in mice. The latency to convulsion and survival rate were significantly longer and higher, respectively, in the brain-injured group than in the sham-operated one. Thus, the results suggest that a protective mechanism develops in the injured brain against asphyxia caused by lidocaine convulsion. PMID- 9365026 TI - Amphetamine sensitization augments amphetamine-induced Fos expression in the lateral habenula. AB - Repeated amphetamine (AMPH) administration results in behavioral sensitization. To investigate the neuroanatomical basis of this phenomenon, we examined the effects of AMPH sensitization on AMPH-induced Fos expression in 24 regions of the rat brain. Rats received repeated injections of AMPH (4 mg/kg, intraperitoneally, once every other day, eight times in total) or saline (same schedule as for AMPH). After a 14-day drug abstinence period, rats were challenged with 2 mg/kg AMPH intraperitoneally. As measured by Fos immunohistochemistry, the AMPH sensitization procedure enhanced subsequent AMPH-induced Fos expression in only one structure, the medial part of the lateral habenula. These results indicate that AMPH-induced behavioral sensitization is not accompanied by widespread increases in the ability of AMPH to increase regional Fos expression in the forebrain. The lateral habenula appears to be involved in the possible neural framework that is responsible for the expression of behavioral sensitization. PMID- 9365027 TI - Effects of intrathecal injection of nimodipine, omega-conotoxin GVIA, calmidazolium, and KN-62 on the antinociception induced by cold water swimming stress in the mouse. AB - The present study was designed to determine if spinal calcium channels, calmodulin, and calcium/calmodulin-dependent protein kinase II were involved in the production of antinociception induced by cold water swimming stress (CWSS). The effects of intrathecal (i.t.) injection of nimodipine, omega-conotoxin GVIA, calmidazolium, or (S)-5-isoquinolinesulfonic acid, 4-[2-[(5-isoquinolinyl sulfonyl)methylamino]-3-oxo-3-(4-phenyl-1-piperaz inyl)-propyl]phenyl ester (KN 62) on CWSS-induced antinociception were studied in ICR mice. The antinociception was assessed by the tail-flick test. CWSS produced inhibition of the tail-flick response. Various doses of nimodipine (10-40 ng), omega-conotoxin GVIA (5-40 ng), calmidazolium (10-40 ng), or KN-62 (5-40 ng) injected i.t. alone did not show any antinociceptive effect in the tail-flick test. I.t. pretreatment with omega conotoxin GVIA, calmidazolium, or KN-62 dose dependently attenuated the CWSS induced inhibition of the tail-flick response. However, i.t. pretreatment with nimodipine did not affect the inhibition of the tail-flick response induced by CWSS. Our results suggest that spinal N-type calcium channel, calmodulin and calcium/calmodulin-dependent protein kinase II may be involved in the production of antinociception induced by CWSS. On the other hand, CWSS-induced antinociception appears not to be mediated via the spinal L-type calcium channel. PMID- 9365028 TI - Multiple divisions of macaque precentral motor cortex identified with neurofilament antibody SMI-32. AB - In brain sections stained with monoclonal antibody SMI-32, which recognizes non phosphorylated neurofilament protein, we distinguished separate caudal, intermediate, and rostral subdivisions of gigantocellular precentral cortex (areas 4c, 4i, and 4r) in macaque monkeys. The divisions form bands extending mediolaterally across the major body-region representations of the primary motor cortex (M1). These observations provide additional evidence that primary motor cortex is not a single, structurally homogeneous cortical area. PMID- 9365029 TI - Topographical analysis of cortical neuronal loss associated with disseminated selective neuronal necrosis and infarction after repeated ischemia. AB - A study was carried out of the distribution and density of the neurons remaining in the gerbil cerebral cortex following two 10-min periods of ischemia at either 3-, 5- or 48-h intervals. As the interval between the periods of ischemia increased, the ischemic injury was reduced from severe to milder infarction, and further from more to less intense disseminated selective neuronal necrosis. This model is suitable for studying the mechanisms of transition from selective neuronal necrosis to infarction at the threshold level of infarction. PMID- 9365030 TI - Glutamate excitation of oxytocin neurones in vitro involves predominantly non NMDA receptors. AB - Experiments were undertaken to compare effects of the NMDA and non-NMDA receptor antagonists, AP5 (40 microM) and NBQX (10 microM), on glutamate-induced firing in supraoptic oxytocin (OT) and vasopressin (VP) neurones in vitro. In putative OT neurones NBQX caused a significantly greater reduction in firing than AP5, whilst in putative VP neurones both antagonists reduced activity powerfully and to a similar extent. The relatively small effect of AP5 in putative OT neurones was unaffected by the removal of extracellular magnesium. These results suggest that glutamate-induced firing in putative OT neurones is predominantly controlled by non-NMDA receptors. PMID- 9365031 TI - Melatonin blocks the induction of long-term potentiation in an N-methyl-D aspartate independent manner. AB - Perfusion of 100 microM melatonin had no effect on low frequency synaptic transmission, but prevented the induction of tetanically induced long-term potentiation (LTP) when recorded in the dendritic region of the CA1 in rat hippocampal slices. Perfusion of 100 microM melatonin in this preparation had no effect on the multiple population spikes recorded in Mg2+-free medium, and, in grease-gap recordings from the CA1-subiculum slice, 100 microM melatonin had no effect on depolarisations evoked by N-methyl-D-aspartate (NMDA) or alpha-amino-3 hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). This suggests that melatonin has the ability to prevent the formation of LTP, and that this effect is not mediated by blockade of NMDA receptors. PMID- 9365032 TI - Polyamine-like immunoreactivity in rat neurons. AB - The localization of polyamine (PA) pools in motor, sensory, and autonomic neurons and in the nerve cells of the hypothalamo-hypophysial system of rats was examined by immunocytochemical method using the monoclonal antibody ASPM-29 specific to spermine (Spm) and spermidine (Spd) fixed in situ. Strong PA immunoreactivity was found in the cytoplasm and dendrites of the large perikaryon of motor neurons in the anterior spinal column, in the Purkinje cells of the cerebellum, in the pyramidal cells of the cerebrum, in the nerve cells of the paraventricular and supraoptic nuclei in the hypothalamus, and in the nerve cells of the spinal and autonomic ganglions. No PA immunoreactivity was seen in the nucleus and nerve terminals of the neurons. The PA immunoreactivities in the motor and sensory neurons were characterized by clustered masses and blocks of immunoreactive cells. Irrespective of location, small and medium-sized neurons were weakly PA positive. The glia cells, some stellite cells, and Schwann cells were almost completely PA-negative. These results may suggest that in neurons PAs are not transported axonally, but are located in conjunction with Nissl bodies (the rough endoplasmic reticulum), specified as sites for protein synthesis within cells. PMID- 9365034 TI - Lack of visual suppression in the rabbit lateral geniculate nucleus during blink reflex. AB - Stimulation of the supraorbital branch of the trigeminal nerve (SO) elicited eye blinks in the rabbit, but did not decrease the amplitude of visual cortical evoked potential from stimulation of the optic chiasm (OX). In addition, the SO stimulation neither induced an inhibitory postsynaptic potential (IPSP) in LGN cells, nor activated inhibitory interneurons in the thalamic reticular nucleus (TRN), which proved to mediate both recurrent inhibition and saccadic suppression in the dorsal lateral geniculate nucleus (LGN). All these indicate that there is no visual suppression in the rabbit LGN during blink reflex. PMID- 9365033 TI - Methylphenidate and brain dopamine neurotoxicity. AB - To further evaluate the dopamine (DA) neurotoxic potential of the widely prescribed psychostimulant, methylphenidate, mice were treated with various doses (range: 10-120 mg/kg) and treatment schedules of methylphenidate (every 2 h x 4 or twice daily x 4). Higher doses of methylphenidate produced intense stereotypy, as well as short- (5-day), but not long- (2-week), term depletions of striatal DA axonal markers. By contrast, amphetamine caused not only intense stereotypy, but also profound, long-lasting, dose-related DA deficits. These findings indicate that results of studies of amphetamine neurotoxicity using short (5-day) post drug survival periods are potentially misleading. Further, the present findings confirm and extend previous results indicating that methylphenidate, unlike amphetamine, lacks DA neurotoxic potential, and strongly suggest that DA efflux, although perhaps necessary, is not sufficient for the expression of amphetamine induced DA neurotoxicity. PMID- 9365035 TI - Interferon-alpha therapy in patients dually infected with hepatitis C virus and GB virus C/hepatitis G virus--virological response of HGV and pretreatment HGV viremia level. AB - BACKGROUND/AIMS: The response to interferon-alpha (IFN) therapy of recently isolated GB virus C and hepatitis G virus (HGV) is still unclear. To investigate the biochemical and virological response to IFN therapy in patients with chronic hepatitis C virus (HCV) infection concomitantly infected with HGV, 196 patients with HCV who had received IFN therapy were retrospectively studied. METHODS: HGV and HCV RNA were detected by reverse transcription nested polymerase chain reaction (RT-PCR). Serum HGV RNA levels were quantified by competitive RT-PCR. The HGV genotype was detected by restriction fragment length polymorphism analysis using the PCR products. RESULTS: Of 196 patients, 16 (8.2%) were positive for both HCV and HGV RNA before IFN therapy. There were no significant clinical and virological differences between the patients with dual infection and those with only HCV infection. During the therapy, a decrease or loss of serum HGV RNA level was observed in these patients. Six months after cessation of the therapy, five of 16 patients became negative for HGV RNA by RT-PCR. The pretreatment HGV RNA level of the patients who lost HGV RNA after cessation of IFN was low (median=10(3) copies/ml), compared to the level (median=10(7) copies/ml, p<0.01) in the patients with positive HGV RNA after the therapy. The HGV genotype of these 16 patients was the same type. CONCLUSIONS: These data suggest that: 1) there is no significant difference in response to IFN therapy between patients with dual and single infection; 2) HGV shows sensitivity to IFN therapy; and 3) in the patients who show a low pretreatment HGV RNA level, serum HGV RNA becomes undetectable by RT-PCR after cessation of IFN therapy. PMID- 9365036 TI - Hepatitis G virus and fulminant hepatic failure: evidence for transfusion-related infection. AB - BACKGROUND/AIMS: In the majority of cases of fulminant "viral" hepatitis in Australia, no known aetiological agent can be isolated. We have examined the possible role of the recently discovered hepatitis G virus (HGV) in such cases. METHODS: An HGV specific reverse transcription polymerase chain reaction (RT-PCR) was performed on pre- and post-liver transplant serum from 14 patients who were referred for transplantation at our unit between 1989 and 1995 for unexplained fulminant hepatic failure. Eleven patients successfully underwent transplantation and three died while waiting for a suitable donor organ. Hepatitis viruses A-E were excluded by standard serological and PCR based testing. HGV RT-PCR was also performed on 21 other, randomly selected, liver transplant recipients ("controls"). RESULTS: The 14 fulminant cases were HGV RT-PCR negative prior to transplantation while five of 21 controls were positive. Post-transplant, eight of the 11 fulminant patients were found to be HGV RT-PCR positive and the same five controls remained HGV RT-PCR positive. In three of the eight fulminant patients the HGV infection resolved. CONCLUSIONS: Our data indicate that HGV infection is unlikely to be responsible for fulminant hepatitis and that it is probably acquired from blood and/or blood products during the transplantation process. Furthermore, long-term carriage of HGV post-transplant is not associated with clinically apparent liver disease. PMID- 9365037 TI - Direct detection of Mycobacterium tuberculosis using polymerase chain reaction assay among patients with hepatic granuloma. AB - BACKGROUND: In liver tuberculosis, demonstration of acid bacilli by conventional methods remains futile. Since the definitive diagnosis of liver tuberculosis is based on the histologic evidence of granulomatous process with caseation necrosis, seen in only a third of cases, the diagnosis is made retrospectively by response to empirical anti-tuberculous drug therapy. AIMS: Our objective is to establish a polymerase chain reaction assay for detection of Mycobacterium tuberculosis affecting the liver using the paraffin-embedded liver biopsy specimens obtained from patients with hepatic granulomas. METHODS: As positive control, patients having either "definitive" (n=8) or "presumptive" (n=9) tuberculosis on the basis of clinical, microbiological, histologic data and their positive response to empirical treatment of anti-tuberculous drugs were used. Patients with hepatic granulomas secondary to schistosomiasis (n=6), sarcoidosis (n=2) and other liver diseases (n=10) were used as negative control. RESULTS: Of those patients who were diagnosed as having "definitive" and "presumptive" liver tuberculosis, positivity by one-step polymerase chain reaction was 100% and 44%, respectively. Using the nested polymerase chain reaction, positivity increased to 78% with "presumptive" liver tuberculosis. In contrast, the polymerase chain reaction assays were negative among all patients with hepatic granuloma due to non-tuberculous-in-origin and other liver diseases. CONCLUSIONS: The overall positivity of this polymerase chain reaction assay (88%) compares favorably with that of other conventional methods (12%). Thus, this polymerase chain reaction assay may be a reliable diagnostic tool for liver tuberculosis in a patient population in which the prevalence of diseases associated with hepatic granuloma is common. PMID- 9365038 TI - Ultrastructural sequences during liver iron overload in genetic hemochromatosis. AB - BACKGROUND/AIMS: The pathway through which iron contributes to liver cell damage and cirrhosis in genetic hemochromatosis is not clear. The objective of the present study was to describe the ultrastructural changes in liver biopsies of patients in various stages of this condition and to correlate these with clinical, histopathological and biochemical data. METHODS: Liver biopsies from 20 patients with genetic hemochromatosis were examined by transmission electron microscopy. The use of unstained thin (60 nm) sections facilitated the identification and localization of the electron-opaque compounds ferritin and hemosiderin in various liver cells. Stained thin sections permitted evaluation of the concomitant subcellular damage and collagen deposition. The ultrastructural observations were corroborated with the histopathological findings and biochemical data. RESULTS: All patients had liver iron overload, which was classified as mild, moderate or severe. In the stage of mild overload (hepatic iron concentration HIC 93.5+/-23.3 micromol/g and hepatic iron index HII 2.3+/ 0.7), cytosolic ferritin and scarce pericanalicular lysosomes (siderosomes) were seen in periportal hepatocytes (acinar zone 1), without evidence of organelle damage, and in the absence of sinusoidal cell siderosis. In moderate overload (HIC 190.8+/-41.5 micromol/g and HII 4.3+/-1.9), ferritin was identified in hepatocytes of all acinar zones, and the pericanalicular siderosomes were abundant, especially in acinar zone 1. Single hepatocytes showed organelle damage and occasional sinusoidal cells showed siderosis. In severe overload (HIC 308+/ 49.0 micromol/g and HII 7.5+/-1.7), hepatocytes of all acinar zones were filled with large, hemosiderin-containing siderosomes, and changes in mitochondria, smooth and rough endoplasmic reticulum and nuclei were conspicuous. Marked sinusoidal cell siderosis and collagen deposition were observed predominantly in this stage. CONCLUSIONS: Electron microscopy has shown that during the long, latent stage of "compensated" genetic hemochromatosis, hepatocytes display only minimal subcellular changes, other than iron overload. "Decompensated" overload, characterized by extensive subcellular pathology and focal necrosis, is reached when 1) the hepatocytic siderosis is generalized (i.e. beyond pericanalicular polarization of siderosomes in hepatocytes, and beyond zone 1 in the acinus); and 2) there is evidence of massive siderosis of sinusoidal cells. These findings support the concept of a critical level of hepatic iron concentration beyond which organelle damage is conspicuous and liver cell injury may become irreversible. PMID- 9365040 TI - Effect of therapeutic paracentesis on plasma volume and transvascular escape rate of albumin in patients with cirrhosis. AB - BACKGROUND/AIMS: Circulatory abnormalities with activation of vasoconstrictor systems after large-volume paracentesis are generally considered secondary to an increased extravasation of fluid from the intravascular compartment to the extravascular space with subsequent reduction in plasma volume. To test this hypothesis, plasma volume, the transvascular escape rate of albumin, the absolute escape rate of albumin and the activity of vasoconstrictor systems were measured in 25 cirrhotic patients with ascites in baseline conditions and 2 days after total paracentesis with plasma volume expansion. METHODS: Plasma volume and the transvascular escape rate of albumin, the fraction of albumin passing from the intravascular to the extravascular space per unit of time, were assessed through the plasma disappearance curve of radioiodinated human albumin. The absolute escape rate of albumin, the total flux of albumin from intravascular to extravascular space per unit of time, was also calculated. RESULTS: Eight of the 25 patients (32%) developed marked activation of vasoconstrictor systems after paracentesis. In these patients, plasma renin activity and plasma norepinephrine concentration increased from 6.6+/-2 to 23.4+/-11 ng x ml(-1) x h(-1) and 776+/ 229 to 989+/-258 pg/ml, respectively (p<0.05). No significant changes in these parameters were found in the remaining 17 patients. The activation of vasoconstrictor systems occurred in the absence of changes in plasma volume (3456+/-276 vs 3476+/-264 ml, NS), transvascular escape rate of albumin (10.4+/-1 vs 10.9+/-2%/h, NS) and absolute escape rate of albumin (9.9+/-1.9 vs 10.5+/-0.7 g/h, NS). CONCLUSIONS: These results do not support a contraction of plasma volume as the mechanism responsible for activation of vasoconstrictor systems after paracentesis. Rather, the activation of vasoconstrictor systems in the absence of changes in plasma volume suggests that paracentesis accentuates the impairment of "effective" blood volume present in cirrhotic patients with ascites. PMID- 9365039 TI - Lipoprotein alterations in liver cirrhosis: a possible contribution to changes in plasma oncotic pressure and viscosity. AB - BACKGROUND/AIMS: To investigate whether physicochemical alterations in plasma lipoproteins are associated with changes in plasma oncotic pressure and viscosity in liver cirrhosis. METHODS: The study included 66 patients with cirrhosis (confirmed by liver biopsy) and 58 healthy volunteers. The constituents measured were: the concentration, density and composition of plasma lipoproteins; plasma oncotic pressure and viscosity; and the concentrations of albumin, total protein, haptoglobin, transferrin, immunoglobulin M and alpha2-macroglobulin. RESULTS: Step-wise multiple regression analysis indicated that, in the patients with cirrhosis, plasma oncotic pressure was significantly correlated with plasma albumin+viscosity (r=+0.85; p<0.001) and with plasma total protein+the density of low density lipoprotein (r=+0.74; p<0.001). The inclusion of viscosity and the density of low density lipoprotein in the regression equations significantly improved the observed correlation between albumin and plasma oncotic pressure (r=+0.70; p<0.001). Similarly, plasma viscosity was significantly correlated with the sum of plasma total protein and cholesterol (r=+0.68; p<0.001). The inclusion of cholesterol in the regression equation significantly increased the observed correlation between total protein and plasma viscosity (r=+0.59; p<0.001). CONCLUSIONS: These results suggest that lipoprotein alterations associated with liver cirrhosis may play a role in determining plasma oncotic pressure and viscosity, and thus could influence the progression of the disease. PMID- 9365041 TI - Changes in blood supply in small hepatocellular carcinoma: correlation of angiographic images and immunohistochemical findings. AB - BACKGROUND/AIMS: To assess the changes occurring in blood flow with growth in small hepatocellular carcinomas, we analyzed the angiographic features and immunohistochemical findings in 35 hepatocellular carcinomas less than 2 cm in diameter. METHODS: Hepatocellular carcinomas were evaluated by digital subtraction angiography (DSA), ultrasound angiography with intraarterial CO2 microbubbles (USAG), and computed tomography during arterial portography (CTAP). Immunohistochemically, hepatocellular carcinomas were evaluated using QB-end/10 (QB) monoclonal antibody. RESULTS: All 18 moderately-differentiated hepatocellular carcinomas stained positively with QB antibody. No hepatocellular carcinomas without attenuation on CTAP were positive by immunohistochemistry, and two hepatocellular carcinomas with attenuation on CTAP also lacked staining. We observed four hepatocellular carcinomas without hypervascularity on DSA or USAG, which stained positively with QB antibody; these hepatocellular carcinomas had fatty metamorphosis. CONCLUSIONS: 1. Immunohistochemical findings are closely associated with angiographic findings regarding changes in blood supply. 2. All moderately-differentiated hepatocellular carcinomas have characteristics of hypervascularity, both by angiographic images and by immunohistochemistry. 3. The increase in arterial blood supply occurs later than the decrease in portal perfusion, which may indicate that the decrease in portal perfusion may not be the direct result of replacement by angiogenesis. 4. Some hepatocellular carcinomas with fatty metamorphosis, which are often hypovascular by angiographic evaluation, have hypervascular immunohistochemical characteristics. PMID- 9365042 TI - Prognostic significance of serum anti-p53 antibody in patients with hepatocellular carcinoma. AB - BACKGROUND/AIMS: Abnormalities of the p53 gene can lead to the production of anti p53 antibody in the serum of cancer patients. We evaluated the prognostic significance of anti-p53 antibody in 86 patients with hepatocellular carcinoma (HCC) in comparison with clinicopathological factors: age, sex, etiology, smoking and drinking habits, history of blood transfusion, presence of encephalopathy and ascites, Child classification, Pugh score, bilirubin, albumin, prothrombin time, indocyanine green retention time at 15 min (ICG), underlying liver disease, alpha fetoprotein (AFP), tumor size, number of tumors, differentiation degree of HCC, presence of extrahepatic metastasis and therapy for HCC. METHODS: The serum anti p53 antibody in 86 patients with HCC, 20 with chronic hepatitis (CH) and 20 with liver cirrhosis (LC) was measured by an enzyme-linked immunosorbent assay (ELISA). A single-strand conformation polymorphism-polymerase chain reaction (SSCP-PCR) analysis and loss of heterozygosity (LOH) study of the p53 gene were performed using 8 tissue samples of 8 HCC from four antibody-positive and four antibody-negative patients. The survival probabilities were assessed by the Kaplan-Meier technique, and a Cox regression analysis was used to identify the independent factors for prognosis. RESULTS: Anti-p53 antibody was positive in 32% (28 of 86) of the sera from patients with HCC, but in none of the 20 with CH and 20 with LC. p53 antibody positivity was associated with bilirubin and the number of tumors (p=0.027 and p=0.018, respectively). Overall survival was shorter in the HCC patients with p53 antibody than in those without p53 antibody (p<0.02). Bilirubin, p53 antibody, AFP and ICG were found to be significant prognostic factors by univariate analysis. A Cox multivariate analysis showed that bilirubin and p53 antibody were independent prognostic variables (p<0.0001 and p=0.003, respectively). In four antibody-positive patients, mutation and LOH of the p53 gene were detected in one patient and two patients, respectively. In contrast, only one of four antibody-negative patients exhibited LOH of the p53 gene. CONCLUSIONS: Serum anti-p53 antibody could be a useful prognostic factor in patients with HCC. PMID- 9365043 TI - Association of cumulative allelic losses with tumor aggressiveness in hepatocellular carcinoma. AB - BACKGROUND/AIMS: Loss of heterozygosity on various chromosomal arms has been reported in hepatocellular carcinoma and a multistep accumulation of genetic alteration has become accepted as the mechanism underlying progression of the disease. Although cumulative genetic alterations may imply more malignant tumors with poorer prognosis, the assumption requires further investigation. METHODS: Presence of loss of heterozygosity was analyzed by microsatellite markers at 13 loci on six chromosomal arms in 56 hepatocellular carcinomas. Association with cumulative allelic losses and prognosis of the patient following curative resection was studied. RESULTS: Frequency of allelic losses at each chromosomal arm was 31% on 1p, 20.6% on 4q, 17.5% on 8p, 17.5% on 13q, 25.5% on 16q and 17.4% on 17p. Thirty-three tumors (59%) presented loss of heterozygosity. Tumors with more allelic losses were significantly more likely to be un-infected by hepatitis C virus, and to be histologically poorly differentiated, to have higher alpha feto protein value, to be advanced in T classification and in tumor stage. Patients with more than one loss of heterozygosity revealed poorer 3-year disease free survival than those with one or no (p=0.0004). A multivariate Cox model analysis revealed cumulative loss of heterozygosity as an independent and influential factor for disease recurrence (relative risk, 2.66; 95% confidence interval, 1.23-5.75; p=0.013), followed by tumor stage. CONCLUSIONS: Cumulative loss of heterozygosity reflects the multistep genetic mechanism of progression of hepatocellular carcinoma. The study confirms the potential significance of genetic analysis in the management of the disease. PMID- 9365045 TI - Identification of human liver carboxylesterase as one of the proteins involved in Plasmodium falciparum malaria sporozoite invasion in primary cultures of human hepatocytes. AB - BACKGROUND/AIMS: In a previous study, we have demonstrated that primary human hepatocytes in culture are susceptible for Plasmodium falciparum sporozoite invasion and for development of parasites into exo-erythrocytic forms. In a separate study we demonstrated the involvement of two human liver plasma membrane proteins (55 kD and 20 kD) in the invasion of P. falciparum sporozoites in vitro. In this study, we have unravelled the nature of the 55 kD protein. METHODS: For the identification of this protein, a 53-58 kD membrane protein fraction from human liver was isolated, radioactively labelled, incubated with sporozoites and cross-linked. After reduction of the cross-linker, the released proteins were mixed with unlabelled 53-58 kD protein fraction and separated on two-dimensional SDS-PAGE. Autoradiography showed a single spot corresponding to a protein of 55 kD and pI of 5.7-5.8. RESULTS: Amino acid sequencing revealed the 55 kD protein as carboxylesterase. The biological activity of purified human liver carboxylesterase and of an antiserum against carboxylesterase on sporozoite invasion in vitro was evaluated. Human carboxylesterase as well as a rabbit antiserum against carboxylesterase inhibited the invasion of P. falciparum sporozoites into primary human hepatocytes in culture. A number of carboxylesterase cDNA clones were isolated from a human liver cDNA library. Sequence analysis revealed two different iso-types. Immunoaffinity purified recombinant human carboxylesterase was shown also to inhibit the invasion of sporozoites into primary human hepatocytes. Immunocytochemical analysis of the localisation of carboxylesterase in primary cultures of human hepatocytes using specific antibodies, showed its presence inside the hepatocytes and on the membrane. CONCLUSIONS: Carboxylesterase plays a role in the invasion process of P. falciparum sporozoites into human hepatocytes in vitro. The implications of these findings are further discussed. PMID- 9365044 TI - Basic fibroblast growth factor regulates proliferation and motility of human hepatoma cells by an autocrine mechanism. AB - BACKGROUND/AIMS: Basic fibroblast growth factor has mitogenic and angiogenic properties. In this study, we aimed to evaluate the role of fibroblast growth factor in the development and progression of human hepatocellular carcinoma. METHODS: The expression of basic fibroblast growth factor, fibroblast growth factor receptor-1, and a receptor isoform was investigated by in situ hybridization, immunohistochemistry, reverse transcription-polymerase chain reaction, Western blot analysis and confocal laser-scanning microscopy. The influence of exogenous basic fibroblast growth factor on DNA synthesis and motility of human hepatoma cells were also evaluated. RESULTS: Basic fibroblast growth factor and fibroblast growth factor receptor-1 messenger RNAs were present mainly in tumor cells and less so in hepatocytes from noncancerous liver tissue. Immunoreactive products of basic fibroblast growth factor and fibroblast growth factor receptor-1 were observed in tumor cells. The isoform IIIc was expressed in hepatocellular carcinoma tissue and hepatoma cell lines. Exogenous basic fibroblast growth factor stimulated DNA synthesis and motility of hepatoma cells. The effect was more marked in poorly-differentiated hepatoma cells than in well differentiated hepatoma cells. Fibroblast growth factor-1 expression on hepatoma cells was also more marked in poorly-differentiated hepatoma cells than in well differentiated hepatoma cells. The stimulated motility on basic fibroblast growth factor was suppressed by an anti-fibroblast growth factor receptor-1 antibody. CONCLUSIONS: Basic fibroblast growth factor may play an important role in the development and progression of hepatocellular carcinoma via an autocrine mechanism involving fibroblast growth factor and its receptor. PMID- 9365047 TI - Calcium and the anionic polypeptide fraction (APF) have opposing effects on cholesterol crystallization in model bile. AB - BACKGROUND/AIMS: Cholesterol gallstones contain both calcium and biliary proteins, but their respective roles in gallstone pathogenesis are unknown. We have studied the effects of calcium and a major biliary protein, anionic polypeptide fraction, on the process of cholesterol crystallization in bile. METHODS: Anionic polypeptide fraction was purified from human bile. Model bile composed of cholesterol, egg yolk lecithin and sodium taurocholate was prepared in a lipid concentration (18 mM, 37 mM, and 120 mM, respectively) simulating lithogenic human gallbladder bile. The crystallization process was observed by phase contrast light microscopy, and sequential separation of precipitable cholesterol structures by sucrose density gradient ultracentrifugation. RESULTS: Addition of calcium, or anionic polypeptide fraction alone, or both together did not influence the crystal observation time of bile (the time which elapsed from initiation of supersaturation to the first appearance of crystals). However, the rate and quantity of cholesterol precipitation and crystal formation were affected by both. Calcium increased in a dose-dependent manner the cholesterol monohydrate crystal mass before apparent equilibrium was reached. This effect was inhibited by anionic polypeptide fraction, which increased the amount of cholesterol within precipitable phospholipid vesicles, and decreased the rate of crystal formation. Fluorescence-labeled anionic polypeptide fraction revealed that anionic polypeptide fraction (with and without calcium) was primarily associated with vesicle aggregates. CONCLUSIONS: Our data demonstrate that calcium and anionic polypeptide fraction have opposing effects on the process of cholesterol crystallization and the resultant crystal mass without influencing the crystal observation time of bile. These findings suggest that biliary proteins, in addition to being crystallization effectors by themselves, may further influence cholesterol crystallization and gallstone formation by interacting with calcium and possibly other elements that coexist in bile. PMID- 9365046 TI - Hepatic bile salt flux does not modulate level and activity of the sinusoidal Na+ taurocholate cotransporter (ntcp) in rats. AB - BACKGROUND/AIMS: Efficient uptake at the basolateral plasma membrane of hepatocytes is required for maintenance of the enterohepatic circulation of bile salts. Uptake occurs mainly via a Na+-dependent process mediated by ntcp, a recently cloned and characterized 51 kDa glycoprotein. The aim of this study was to evaluate the role of variations in hepatic bile salt flux through the liver in the regulation of ntcp activity and expression under non-cholestatic conditions. METHODS: We determined the kinetics of Na+-dependent taurocholate transport in isolated basolateral plasma membrane vesicles as well as hepatic ntcp protein and ntcp mRNA levels in long-term (8 days) bile-diverted rats, with a transhepatic bile salt flux of 0, and in streptozotocin-induced diabetic rats with a 2.5-fold increased bile salt flux. RESULTS: We found no changes in the kinetics of taurocholate transport in the absence of transhepatic bile salt flux due to bile diversion. Ntcp protein and ntcp mRNA levels were also unaffected in bile diverted rats. Likewise, no changes in taurocholate transport kinetics, ntcp protein or ntcp mRNA levels were detected in streptozotocin-diabetic rats when compared to non-diabetic controls. Thus, variation in hepatic bile salt flux from 0 to 250% of normal values had no effect on hepatic ntcp expression or taurocholate transport activity in basolateral plasma membrane vesicles in rats. In contrast, 4 days of bile duct ligation resulted in a strong decrease in ntcp mRNA and protein levels, as recently also reported by others. CONCLUSIONS: Our data indicate that ntcp is not regulated by the transhepatic flux of bile acids under non-cholestatic conditions. PMID- 9365048 TI - Unidirectional upregulation of the synthesis of the major iron proteins, transferrin-receptor and ferritin, in HepG2 cells by the acute-phase protein alpha1-antitrypsin. AB - BACKGROUND/AIMS: We have previously shown that the hepatic acute-phase protein alpha1-antitrypsin (alpha1-AT) is an important mediator of changes in iron metabolism in the course of anaemia of chronic disease. Alpha1-AT profoundly reduces growth of erythroid cells by interfering with transferrin-mediated iron uptake. In the present work we investigate the effects of alpha1-AT on hepatic iron metabolism, as the liver plays a central role in body iron metabolism and in metabolic changes during acute-phase response. METHODS: The human hepatoma cell line Hep G2 was cultured in RPMI 1640+10% FCS. The effect of alpha1-AT on transferrin-receptor binding was investigated in equilibrium binding assays with 125I-transferrin. Expression of transferrin receptor was determined by saturation experiments and intracellular ferritin was measured in cell lysates after incubating cells either alone or with alpha1-AT. To determine iron regulatory protein binding activity to iron responsive elements we used gel retardation assays and Northern blot analysis was carried out to investigate transferrin receptor and ferritin mRNA expression. RESULTS: Alpha1-AT completely prevented transferrin from binding to its receptor and internalization of the transferrin transferrin receptor complex on HepG2. In addition, alpha1-AT caused a distinct increase in iron regulatory protein binding activity to iron responsive elements, which is characteristic of iron deprivation. Normally, the synthesis of transferrin receptor and ferritin is regulated bidirectionally, but alpha1-AT promoted a unidirectional regulation. Alpha1-AT increased the synthesis of both transferrin receptor and ferritin and, moreover, increased cellular amounts of transferrin receptor mRNA and ferritin H-chain mRNA. CONCLUSIONS: The effect of alpha1-AT on transferrin receptor synthesis appears to be mediated via activation of iron responsive element binding affinity of iron regulatory protein leading to an increased stability of transferrin receptor mRNA. Changes in ferritin, however, may be related to a transcriptionally mediated, iron-independent pathway which overrides the influence of activated iron regulatory protein. These specific changes in iron metabolism are the very ones seen in the course of anaemia of chronic disease. Our results emphasize the central role of alpha1-AT as a mediator of altered iron metabolism, characteristic of anaemia of chronic disease, not only with respect to erythroid cells but also with respect to liver cells. PMID- 9365049 TI - Therapeutic vaccination of woodchucks against chronic woodchuck hepatitis virus infection. AB - BACKGROUND/AIMS: Therapeutic vaccination is a new approach to treat patients with chronic hepatitis B virus infection. We have used the woodchuck model to examine the efficacy and safety of this approach. METHODS: Seven woodchucks chronically infected with woodchuck hepatitis virus were immunized with surface antigen from this virus, purified from plasma, in conjunction with a peptide named FIS (encompassing amino acids 106-118: FISEAIIHVLHSR from sperm whale myoglobin), which is recognized by T helper lymphocytes. As controls, two woodchucks chronically infected with woodchuck hepatitis virus were immunized: one with FIS only and the other with surface antigen only. RESULTS: Co-immunization with surface antigen and FIS, but not with FIS or surface antigen alone, induced anti surface antibodies in 7/7 immunized woodchucks. In the two woodchucks in which the highest titer of anti-surface antibody was elicited, severe liver damage was observed: one died of fulminant hepatitis and the other became seriously ill with hepatic injury and had to be sacrificed. CONCLUSIONS: Co-immunization of chronically infected woodchucks with surface antigen and a peptide recognized by T helper cells produces a good anti-surface antibody response. However, this strategy needs to be optimized before its implementation in humans. Although our experiments are not strictly comparable to vaccination of chronically hepatitis B virus-infected patients with recombinant or plasma-derived vaccines, we believe that precautions should be taken to avoid the risk of severe liver injury when immunizing hepatitis B virus carriers. PMID- 9365050 TI - Influence of 48 hours of cold storage in University of Wisconsin organ preservation solution on metabolic capacity of rat hepatocytes. AB - BACKGROUND/AIMS: Suspensions of isolated hepatocytes are a valuable tool to study liver functions. For optimal use of the isolated hepatocytes, methods are needed to preserve the hepatocytes while maintaining their viability, metabolic and transport functions. Until now, little has been known about the maintenance of the drug metabolism capacity and energy state, measured by the so-called energy charge (ATP+1/2ADP)/(ATP+ADP+AMP), in hepatocytes after storage in University of Wisconsin cold storage solution (UW). Consequently, we investigated whether UW, originally designed to preserve organs for transplantation, was suitable for preservation of isolated rat hepatocytes with respect to the maintenance of drug metabolism and levels of energy-rich substrates. METHODS: Viability of the isolated rat hepatocytes was determined by trypan blue exclusion, ATP content and energy charge after 24 and 48 h of storage in UW at 0 degrees C. Phase I and II metabolic functions of the cells were studied by measuring the cytochrome P450 content and the metabolic rate of lidocaine and 7-ethoxycoumarin. RESULTS: During 48 h of storage of hepatocytes in UW both phase I and phase II metabolism are preserved at control levels. After storage, the viability of the hepatocytes was not changed significantly, and the cells maintained proper cellular ATP content and overall energy charge. CONCLUSIONS: These results imply that hepatocytes from a single isolation can be stored in UW solution and used for metabolism experiments for 3 consecutive days, allowing a reduction in the use of experimental animals. PMID- 9365051 TI - A novel variant of lysosomal acid lipase in cholesteryl ester storage disease associated with mild phenotype and improvement on lovastatin. AB - Cholesterol ester storage disease (CESD) is a rare congenital disorder of lipid metabolism, with mutation of the lysosomal acid lipase gene, causing chronic liver disease, usually before adolescence. We here describe three adult siblings with CESD diagnosed by light microscopic demonstration of excessive lysosomal storage of lipids with accumulation of foamy cells in liver biopsies and by a decrease in acid lipase activity (2-3% of controls). One patient (male, 46a) had extensive liver fibrosis, another (female, 58a) had cirrhosis of the liver. The third patient had died from variceal haemorrhage (female, 56a). Using sequence analysis of RT-PCR products of LAL mRNA, the patients were identified as compound heterozygotes for a G-->A substitution at position -1 of the exon 8 splice donor site and a point mutation at the second allele, resulting in a His108-->Pro shift. In two patients, therapy with lovastatin was initiated, which led to normalisation of serum cholesterol and triglyceride levels. After 12 months, liver biopsy demonstrated a significant decrease in vacuolisation of hepatocytes, with fewer and smaller droplets. Semi-automated computer-assisted image analysis of electron microscopic sections demonstrated a decrease in the hepatocellular lysosomal area from 20.5+/-7.1% to 11.7+/-6.5% (p<0.05) and 41.7+/-5.1% to 33.4+/ 4.4% (p<0.01). We conclude that in two siblings with a novel LAL variant and mild phenotype of CESD, lovastatin decreased both serum lipid concentrations and hepatocellular lysosomal content. PMID- 9365052 TI - A 12-year-old girl with antimitochondrial antibody-positive autoimmune hepatitis. AB - Autoimmune hepatitis is rare and, in childhood, is typically associated with either the nuclear and/or smooth muscle antibody or with the liver kidney microsomal type 1 antibody. Antimitochondrial antibodies, which are considered diagnostic of primary biliary cirrhosis, have not been described in the paediatric age. We report for the first time a 12-year-old girl with antimitochondrial-antibody-positive autoimmune hepatitis. Antimitochondrial antibody positivity was determined by immunofluorescence and immunoblot. The patient's age, clinical, biochemical and histological features and response to immunosuppressive treatment support the diagnosis of autoimmune hepatitis. PMID- 9365053 TI - Images in hepatology: "cholangitis carcinomatosa". PMID- 9365054 TI - Treatment of hepatocellular carcinoma in patients with cirrhosis. PMID- 9365055 TI - Intrafamilial transmission of hepatitis C virus: sexual and non-sexual contacts. PMID- 9365056 TI - Efficacy of interferon therapy for patients who develop chronic hepatitis C after an acute course of hepatitis. PMID- 9365057 TI - Activation of the endogenous interferon system, expression of interferon-alpha receptors, and response to interferon therapy in chronic hepatitis C. PMID- 9365058 TI - Effect of interferon therapy on viral titers in patients with chronic hepatitis C who are positive for hepatitis GB virus C. PMID- 9365059 TI - Cerebral arteriovenous malformations in childhood: state of the art with special reference to treatment. AB - In this state of the art paper, the clinical and diagnostic features of cerebral arteriovenous malformation (AVM) in childhood are outlined and special attention is paid to the treatment. Several options exists for the treatment of an AVM, consisting of surgery, endovascular embolization, stereotactic radiosurgery, or a combination of these treatments. PMID- 9365060 TI - The role of serotonin re-uptake inhibitors in preventing recurrent unexplained childhood syncope -- a preliminary report. AB - To assess the efficacy of a serotonin re-uptake inhibitor, sertraline hydrochloride, in preventing recurrent neurocardiogenic syncope, we studied 15 patients (10 female; mean age 12.9 +/- 2 years) with positive head-upright tilt test and resistant to standard pharmacotherapy, atenolol or disopyramide. The patients were given 50 mg oral sertraline hydrochloride daily for 6 weeks. Intolerance to the drug was seen in 3 patients and 2 had syncopal episodes during the therapy. A head-upright tilt table test was then repeated in 10 patients. Six were tilt negative and asymptomatic over a mean follow up period of 7 +/- 3 months while four remained tilt positive: two experienced marked hypotension and bradycardia, characterized as mixed type syncope, and two had cardiac asystole, lasting > 10 s, during tilting, thereby exhibiting a cardio-inhibitory response. CONCLUSION: Sertraline hydrochloride may be useful in preventing recurrent neurocardiogenic syncope resistant to standard pharmacotherapy but careful clinical studies are essential before such a treatment strategy can be recommended since serious asystole could develop. PMID- 9365061 TI - Progressive left main coronary artery obstruction leading to myocardial infarction in a child with Williams syndrome. AB - We report a 3-year-old child with Williams syndrome in whom the first vascular feature of the syndrome was a myocardial infarction related to the occlusion of the left main coronary artery trunk. This coronary artery occlusion was not associated with supravalvular aortic stenosis. CONCLUSION: This report emphazises that acute vascular events related to systemic artery anomalies may reveal Williams syndrome. PMID- 9365062 TI - Persistent hyperinsulinaemic hypoglycaemia of infancy: therapy, clinical outcome and mutational analysis. AB - Persistent hyperinsulinaemic hypoglycaemia of infancy (PHHI) is an autosomal recessive disorder characterized by irregular insulin secretion leading to hypoglycaemia. Recently, mutations in the sulphonylurea receptor (SUR) have been described in association with PHHI. We studied clinical symptoms, therapy, long term outcome and mutational analysis in 14 patients with PHHI. In 8 patients subtotal pancreatectomy was performed whereas 6 responded to conservative treatment with diazoxide. Psychomotor retardation was found in 6 patients, most of them after a delayed diagnosis. A G-to-A point mutation in one allele of the SUR gene was detected by loss of a MspI restriction site in only one patient. CONCLUSION: Early diagnosis and therapy in PHHI is essential to prevent brain damage. In one patient mutational analysis suggested compound heterozygosity for a known and an as yet unidentified mutation in the SUR gene. PMID- 9365063 TI - Magnetic resonance images of 91 children with different causes of short stature: pituitary size reflects growth hormone secretion. AB - In order to validate an association between pituitary size and severity of growth hormone deficiency (GHD) we evaluated the magnetic resonance images (MRI) of 107 children with different causes of short stature. Ninety-one MRIs were evaluable (64 male, 27 female; age: 9.1 +/- 3.9 years). The levels of insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3), and tests of GH stimulation and spontaneous secretion, led to the following subgroups: severe isolated GHD (SIGHD) (GH < 7 ng/ml) (n = 21); partial, isolated GHD (GH 7-10 ng/ml) (n = 22); multiple pituitary hormone deficiency (MPHD) (n = 13); neurosecretory dysfunction (n = 10); non-classifiable diagnosis (NC) (n = 13); idiopathic short stature (n = 9); and intra-uterine growth retardation (n = 3). Pituitary height (PHT) was measured and hypoplasia was assumed when PHT was < -2 SDS. An ectopic posterior pituitary with missing stalk and a hypoplastic anterior pituitary was present in 12 (57%) SIGHD cases, 12 (92%) MPHD cases and 1 patient from the NC group. An isolated hypoplastic anterior pituitary was observed in 15%-33% of the other groups. PHT (mm; mean, SD) in MPHD (1.7 +/- 0.5) was lower than in SIGHD (2.7 +/- 1.0, P < 0.05), with PHT of both groups being lower than in all the other groups (3.8 +/- 0.9, P < 0.0001). PHT SDS correlates with IGF-I SDS (r = 0.48, P < 0.0001), IGFBP-3 SDS (r = 0.46, P < 0.0001) and the highest peaks in tests of GH stimulation and GH spontaneous secretion (r = 0.36, P < 0.0001). In contrast to all the other groups, no correlation with age was observed in MPHD and SIGHD. Breech delivery was recorded in up to 26% of patients in all seven groups. Surprisingly, only 1 out of 23 patients with an ectopic posterior pituitary was born by breech delivery, suggesting that ectopia of the posterior lobe is not necessarily related to breech delivery. CONCLUSION: PHT is significantly correlated with GH secretion in several types of short stature. Patients with ectopic posterior pituitary, missing stalk and hypoplastic anterior pituitary either suffer from SIGHD or MPHD, and this anatomical defect is not necessarily related to breech delivery. PMID- 9365064 TI - Growth impairment and growth hormone therapy in children treated for malignant brain tumours. AB - Eighty-two children with malignant brain tumours were treated according to the "8 in 1" chemotherapy protocol in Finland during 1986 to 1993. Thirty-seven with brain tumours not involving the hypothalamic-pituitary region are still alive and tumour-free. The growth and response to growth hormone (GH) therapy in these children was analysed. Children who received craniospinal irradiation had the most severe loss of height SDS, being -1.07 within 3 years of the diagnosis. Even children with no irradiation to the hypothalamic-pituitary axis had a mean change in height SDS of -0.5 after 3 years. Fifteen of 23 children who received craniospinal irradiation and two out of eight children who received cranial irradiation have received GH therapy. A catch-up growth response to the daily GH therapy with the mean dose of 0.7 IU/kg per week was complete in 3 years (+1.87 SDS), irrespective of craniospinal irradiation, in children who were treated at prepubertal age but was seen in none of the children who had reached pubertal age. CONCLUSION: Growth impairment and GH deficiency are common in children treated for malignant brain tumours. The response to GH therapy is good in prepubertal children in terms of increased growth velocity, although the final height is not yet known. PMID- 9365065 TI - Faecal elastase 1 in children with cystic fibrosis. AB - Recently, a new ELISA kit for determination of elastase 1 in faeces has become commercially available. Studies in patients with chronic pancreatitis have indicated that it is a simple and sensitive test of exocrine pancreatic function. The aim of this study was to assess the clinical value of this new test in cystic fibrosis. A total of 72 children were studied: 27 who were healthy, 22 with cystic fibrosis and 23 with non-pancreatic disorders. Oral pancreatic extracts were not discontinued in the children with cystic fibrosis. A small sample of faeces was collected from each subject for elastase 1 concentration and chymotrypsin activity determination. In all of the healthy children and most of those with non-pancreatic disorders (20/23), elastase 1 concentrations were greater than 500 microg/g; in contrast, the vast majority (20/22) of children with cystic fibrosis had very low values (less than 20 microg/g). The differences between children with cystic fibrosis and the other two groups were highly significant (P < 0.001). With a cut-off level of 132 microg/g, the sensitivity and specificity of faecal elastase 1 for the determination of exocrine pancreatic insufficiency were 96% and 100%, respectively. The specificity of faecal chymotrypsin was 96%, but its sensitivity was not calculated since the children with cystic fibrosis continued to take pancreatic extracts during the study. CONCLUSION: The determination of faecal elastase 1 concentration is a simple and reliable means of assessing exocrine pancreatic function in children with cystic fibrosis. Results are not influenced by non-pancreatic disorders or by enzyme supplementation. PMID- 9365067 TI - Short stature and failure of pubertal development in thalassaemia major: evidence for hypothalamic neurosecretory dysfunction of growth hormone secretion and defective pituitary gonadotropin secretion. AB - In patients with beta-thalassaemia major, frequent blood transfusions combined with desferrioxamine chelation therapy lead to an improved rate of survival. Endocrine disorders related to secondary haemosiderosis such as short stature, delayed puberty and hypogonadism are major problems in both adolescent and adult patients. A total of 32 patients with beta-thalassaemia major undergoing treatment at the Children's Hospital, University of Gottingen were examined. Fourteen of these were short in stature. Growth hormone (GH) secretion was investigated in 13 patients exhibiting either a short stature or reduced growth rate. The stimulated GH secretion of 10 patients in this subgroup lay within the normal range. Studies of their spontaneous GH secretion during the night revealed that these patients had a markedly reduced mean GH and reduced amplitudes in their GH peaks. Low insulin-like growth factor (IGF)-I levels were seen in the growth-retarded thalassaemic patients. Eight were subjected to an IGF generation test and showed a strong increase in both IGF-I and insulin-like growth factor binding protein (IGFBP)-3 levels indicating intact IGF-I generation by the liver. Hypogonadotropic hypogonadism was found to be present in both the male and female patients with impaired sexual development. After priming with LH-releasing hormone (GnRH) per pump in 2 female and 5 male patients, no change in either their serum oestradiol or testosterone levels or in LH/FSH response to GnRH was observed suggesting that they were suffering from a severe pituitary gonadotropin insufficiency. Three male patients at the age of puberty but exhibiting short stature. low GH, low IGF-I and hypogonadism received low dose long-acting testosterone. After 3 12 months of therapy there was a marked growth spurt, higher nocturnal GH levels and an increase in both IGF-I and IGFBP-3. CONCLUSION: Reduced GH secretion and low IGF-I in thalassaemic patients are related to a neurosecretory dysfunction due to iron overload rather than to liver damage. Hypogonadotropic hypogonadism is caused by the selective loss of pituitary gonadotropin function. In patients with both GH deficiency and hypogonadism, low dose sexual steroid treatment should be considered either as an alternative or an additional treatment before starting GH therapy. PMID- 9365066 TI - Spontaneous remission of chronic hepatitis C in children. AB - The clinical course of 48 children with chronic hepatitis C (33 boys, 15 girls; mean age: 12.2 years) was monitored for more than 3 years to clarify its natural course. All patients were positive for the second-generation antibody to hepatitis C virus (anti-HCV) and for serum hepatitis C virus (HCV) RNA. All but one patient had a history of blood transfusion. Serum levels of alanine aminotransferase (ALT) had been abnormal for more than 1.5 years. Spontaneous remission defined as a biochemical remission lasting more than 1 year in association with the disappearance of serum HCV RNA, occurred in 4 (8.3%), however, in 25%, HCV RNA was still detectable in the liver even after its disappearance from serum. In this patient, the level of antibody to HCV core antigen (anti-HCV core) did not decrease significantly and serum HCV RNA eventually reappeared. The serum titre of HCV RNA in the 4 children with spontaneous remission was lower than in the remaining 44 children. Spontaneous remission may occur in children with chronic hepatitis C in whom the serum titre of HCV RNA is low and serum level of anti-HCV core decreases significantly. Assessment of the intrahepatic HCV RNA is necessary to confirm complete remission. CONCLUSION: A low serum titre of HCV RNA and a significant decrease in the serum titre of anti-HCV core were associated with spontaneous remission in children with chronic hepatitis C. Intrahepatic HCV RNA assessment is necessary to confirm complete remission. PMID- 9365069 TI - Abdominal ultrasonography in the diagnostic work-up in children with recurrent abdominal pain. AB - We report on our experience with routine abdominal ultrasonography in 120 children (aged 3-15 years) with recurrent abdominal pain, in order to determine the diagnostic value of this investigation. Eight children (7%) revealed sonographic abnormalities: gallbladder stone (n = 2), splenomegaly (n = 1) and urogenital abnormalities (n = 5). The recurrent abdominal pain could be explained by these findings in only two (may be three) cases. CONCLUSION: The diagnostic value of abdominal ultrasonography in unselected children with recurrent abdominal pain is low. However, the direct visualization of the abdominal structures as being normal may be helpful to the parents and the child in their understanding and acceptance of the benign nature of recurrent abdominal pain. PMID- 9365068 TI - Development of a testicular haemangioma after interferon therapy for hepatic haemangiomas: a case report. AB - We report a 2-month-old Japanese boy presenting with large multiple haemangiomas invading his liver. He was treated with daily subcutaneous injection of interferon alfa (IFN-alpha)-2a with progressive reduction of the hepatic haemangioma. He developed a scrotal mass 2 months after discontinuation of IFN, and this mass eventually required surgical management. Resected tumour was a juvenile haemangioma. The escape of this haemangioma from IFN therapy may be correlated to the quite low level of injected IFN in testis. CONCLUSION: IFN therapy may not be curative for testicular haemangioma although it is effective in shrinking haemangiomas of the liver and skin. PMID- 9365070 TI - Cerebral complications in Schimke immuno-osseous dysplasia. AB - Schimke immuno-osseous dysplasia is a multisystem disorder consisting of spondylo epiphysial dysplasia, progressive renal insufficiency due to focal segmental glomerulosclerosis, and immunodeficiency. Cerebrovascular complications have only been described in five patients. Here we report a patient with prominent neurological symptoms most likely caused by transient ischaemic attacks. CONCLUSION: Neurological symptoms consisted of repeated brief spells of hemiparaesthesia, motoric aphasia and diplopia. MRI studies of the CNS revealed progressive white matter lesions. Morphological changes as well as neurological deficits are compatible with cerebral ischaemia. PMID- 9365071 TI - Treatment of osteogenesis imperfecta with the bisphosphonate olpadronate (dimethylaminohydroxypropylidene bisphosphonate). AB - Osteoporosis is an important feature of osteogenesis imperfecta (OI). So far, no effective medical treatment is available. We treated three boys with severe OI type III and vertebral deformities for 5-7 years with continuous oral administration of the bisphosphonate, olpadronate. Treatment resulted in a decreased number of bone fractures, an increased calcification of the long bones and an amelioration of vertebral shape. No side-effects were encountered. CONCLUSION: These preliminary but long-term observations suggest that the bisphosphonate olpadronate may be a useful treatment for patients with OI and vertebral fractures. Bisphosphonates may be promising drugs for children with OI. PMID- 9365072 TI - Carnitine administration ameliorates the changes in energy metabolism caused by short-term pivampicillin medication. AB - Ten children receiving pivampicillin for 8 days were studied. On the first 4 days the drug was given alone (4 x 500 mg/day), and on the last 4 days in combination with carnitine (4 x 1 g/day). Pivampicillin treatment was associated with formation and urinary excretion of pivaloylcarnitine and administration of carnitine aided the elimination of pivalate as its carnitine ester. The resting respiratory quotient increased from 0.86 +/- 0.01 to 0.96 +/- 0.01 on the 4th day of pivampicillin treatment. A shift was observed in the metabolic fuel consumption: a significant decrease was found in the amount of fats oxidized (0.31 +/- 0.17 vs 1.27 +/- 0.17 g x kg[-1] x 24 h[-1]). while the utilization of carbohydrates increased (6.20 +/- 0.51 vs 4.00 +/- 0.50 g kg[-1] x 24 h[-1]). Administration of carnitine decreased the respiratory quotient to 0.90 +/- 0.01 on the 8th day of treatment, consumption of fats increased, and the oxidation of carbohydrates decreased. The resting energy expenditure was not affected by the treatment. CONCLUSION: Pivampicillin treatment results in inhibited oxidation of fats as metabolic fuel. This drug effect was partially reversed by carnitine which promotes the elimination of the pivaloyl moiety from the body. PMID- 9365073 TI - Stridor as the major presenting symptom in riboflavin-responsive multiple acyl CoA dehydrogenation deficiency. AB - Inspiratory stridor of unknown origin was the leading clinical symptom in an 11 month-old boy. The stridor increased over a period of 4 weeks, and assisted ventilation became necessary. Selective urinary screening by gas chromatography/mass spectrometry analysis revealed excretion of ethylmalonic and 3-OH-isovaleric acid and of N-isobutyryl-, N-2-methylbutyryl-, N-isovaleryl-, N hexanoyl- and N-suberylglycine. Neither hypoglycaemia nor metabolic acidosis were noticed. Treatment with 200 mg of riboflavin per day led to a dramatic clinical improvement with restoration of normal respiration and an increase in muscular tone within 2 months. During this period, metabolite excretion in urine completely normalized. Riboflavin-sensitive multiple acyl-CoA dehydrogenation deficiency was confirmed in cultured fibroblasts. With riboflavin supplementation, the development of the child has been favourable, with normal school attendance now at an age of 9 years. CONCLUSION: As respiratory symptoms might precede other symptoms in disorders of mitochondrial oxidation, we propose determination of urinary organic acids in all cases of unexplained laryngeal stridor. PMID- 9365074 TI - Extreme hyperbilirubinaemia in Zimbabwean neonates: neurodevelopmental outcome at 4 months. AB - As part of a prospective study of severely jaundiced Zimbabwean infants, the relationship between maximum total serum bilirubin (TSB) concentration in the neonatal period and neurodevelopmental outcome at the corrected age of 4 months was studied. Fifty infants with a TSB of > 400 micromol/l (23.4 mg/dl) were enrolled and screened with a neonatal neurological examination (NNE). The cause of jaundice was low birth weight in 22 (44%), ABO incompatability in 8 (16%), sepsis in 8 (16%) and congenital syphilis (6%) in 3 infants. In 9 infants a cause could not be determined. At 4 months, 2 infants had died and 3 were lost to follow up, leaving 45 infants for the infant motor screen (IMS) at 4 months of age. Mean TSB in the neonatal period was 485 micromol/l (28.2 mg/dl), and 7 infants received an exchange transfusion. Mean TSB of the infants with an exchange transfusion was 637 micromol/l (37.2 mg/dl) (range 429-865 micromol/l (25-50.3 mg/dl)) and of the infants without transfusion 459 micromol/l (26.8 mg/dl) (range 400 740 micromol/l (23.4-43 mg/dl)) (P < 0.0001). The TSB was not associated with birth weight, gestational age, gender or head circumference of the baby. On the IMS, 6 of 45 (13.3%) infants scored abnormal, 6 (13.3%) suspect and 33 (73%) scored normal. Three of the six (50%) remaining infants who received an exchange transfusion scored abnormal on the IMS while only 3 of the 39 (8%) infants without exchange transfusion were abnormal. CONCLUSION: More than 25% of infants with a TSB of > 400 micromol/l (23.4 mg/dl) scored abnormal or suspect at 4 months of age and half of these infants already showed irreversible neurological symptoms. All infants who scored abnormal or suspect on the IMS with bilirubin levels between 400 and 500 micromol/l (23.4 and 29.2 mg/dl) had haemolytic disease or were premature. PMID- 9365075 TI - Detection of movement artifact in recorded pulse oximeter saturation. AB - Movement artifact (MA) must be detected when analysing recordings of pulse oximeter saturation (SpO2). Visual analysis of individual pulse waveforms is the safest, but also the most tedious, method for this purpose. We wanted to test the reliability of a computer algorithm (Edentec Motion Annotation System), based on a comparison between pulse and heart rate, for MA detection. Ten 12-h recordings of SpO2, pulse waveforms and heart rate from ten preterm infants were analysed for the presence of MA on the pulse waveform signal. These data were used to determine the sensitivity and specificity of the computer algorithm, and of the oximeter itself, in detecting MA. Recordings were divided into segments of 2.5 s duration to compare the movement identification methods. Of the segments 31% +/- 6% (mean +/- SD) contained MA. The computer algorithm identified 95% +/- 3% of these segments, the pulse oximeter only 18% +/- 11%. Specificity was 85% +/- 4% and 99% +/- 0%, respectively. SpO2 was < or =80% in 3% +/- 1% of segments. 88% +/ 7% of the pulse waveform signal showed MA during this time, leaving a significant potential for erroneous identification of hypoxaemia. Recordings of SpO2 do not allow a reliable identification of MA. CONCLUSION: Without additional information about movement artifact, a significant proportion of recording time of pulse oximeter signal may be regarded as demonstrating hypoxaemia which, in fact, simply reflects poor measurement conditions. The computer algorithm used in this study identified periods of movement artifact reliably. PMID- 9365076 TI - Case of the month: a girl with oedema and purpuric eruption. Diagnosis: acute haemorrhagic oedema of infancy. PMID- 9365077 TI - Congenital erythropoietic porphyria, description of a new mutation in two brothers. PMID- 9365078 TI - The Hoyeraal-Hreidarsson syndrome: the presentation of the seventh case. PMID- 9365079 TI - Apoptosis in the rheumatic diseases. PMID- 9365080 TI - The neuroscience and endocrinology of fibromyalgia. PMID- 9365081 TI - Clinical response to nonsteroidal antiinflammatory drugs. PMID- 9365082 TI - Nonsteroidal antiinflammatory drugs in rheumatoid arthritis and osteoarthritis: support for the concept of "responders" and "nonresponders". AB - OBJECTIVE: A range of functional, biochemical, and psychological indicators was used to test the concept of "responders"/"nonresponders" and to seek predictors of response to 2 nonsteroidal antiinflammatory drugs in 9 patients with rheumatoid arthritis (RA) and 11 with osteoarthritis (OA). METHODS: In a balanced, randomized, double-blind, latin-square study design that involved four 4-week treatment periods, patients received ketoprofen or piroxicam (each for 2 of the 4 periods). Clinical and laboratory responses (pain, tenderness, swelling, patient and physician global assessments, acute-phase protein levels, and disability) were assessed in the last 2 weeks of each period. Responders were those who showed >30% improvement in at least 5 of 7 measures of disease activity. Mood was also assessed. RESULTS: At baseline, variables were higher in RA than in OA patients. The drugs produced clear improvements in patients' visual analog scale scores, physicians' overall assessments, and patients' responses to the McGill Pain Questionnaire, as well as plasma prostaglandin concentrations. In patients with either RA or OA, responders could be distinguished from nonresponders; about one-third of patients were unambiguous responders. In RA, there were responder/nonresponder differences in lymphocyte counts, erythrocyte sedimentation rate (ESR), and levels of tumor necrosis factor alpha, but no differences were seen in OA patients. However, caution in interpretation of the data is necessary because of the small number of patients. Responders had improved mood scores compared with nonresponders in both disease groups. Baseline ESR and white blood cell counts were correlated with responder status in RA patients. CONCLUSION: This study provides support for the responder/nonresponder concept. It also indicates that in RA, pretreatment ESR and lymphocyte counts are possibly useful indicators of therapeutic response. PMID- 9365083 TI - Blood transfusion, smoking, and obesity as risk factors for the development of rheumatoid arthritis: results from a primary care-based incident case-control study in Norfolk, England. AB - OBJECTIVE: To examine a range of demographic, social, and clinical risk factors for the development of rheumatoid arthritis (RA). METHODS: Population-based case control study in Norfolk, England, involving adult patients, ages 18-70, with an inflammatory polyarthritis of <12 months' duration who were recruited from the Norfolk Arthritis Register. Controls, matched for sex and date of birth, were selected from the primary care register of the Norwich Health Authority. Both cases and controls completed identical self-administered questionnaires. Matched analysis of the 165 case-control sets was conducted for the whole group and for the subset in which the cases satisfied the 1987 American College of Rheumatology criteria for RA. RESULTS: The controls were of higher socioeconomic status than the cases. This was probably due to response bias. Having a body mass index > or =30 was associated with an adjusted odds ratio (OR) of 3.74 for developing RA (95% confidence interval [95% CI] 1.14-12.27). RA was also associated with a history of blood transfusion (OR 4.83, 95% CI 1.29-18.07). Even after correcting for social class, a history of having ever smoked was associated with a higher risk of developing RA (OR 1.66, 95% CI 0.95-3.06). There was no difference between cases and controls in previous exposure to childhood infections, certain surgical procedures, or reproductive history variables. CONCLUSION: RA has a number of potential environmental triggers, including smoking, obesity, and blood transfusion. PMID- 9365084 TI - Juvenile rheumatoid arthritis in affected sibpairs. AB - OBJECTIVE: To describe the demographics and clinical disease in affected sibpairs (ASPs) with juvenile rheumatoid arthritis (JRA), and to compare JRA as it occurs in ASPs with that from non-ASP JRA populations described in the literature. METHODS: A rare disease research registry was established with a focus on JRA ASPs to facilitate accrual of patients for genetic, epidemiologic, and clinical studies. Physicians likely to care for patients with JRA were made aware of the registry and its goals by a variety of methods and asked to refer patients for entry. RESULTS: To date, 71 ASPs have been registered and complete information has been obtained. These affected sibs differed in age by a mean of 4.1 years (SD 3.4) and in age at disease onset by 2.8 years (SD 3.0). The actual time difference between onset in sib 1 versus sib 2 averaged 4.4 years (SD 4.2). Sixty three percent of the sibpairs were concordant for sex, and 76% for JRA onset type. Onset type within sibpairs did not appear to be random, based upon comparisons with non-ASP populations. Greater than expected concordance was seen among those with pauciarticular-onset and polyarticular-onset JRA. Seventy-nine percent of the pairs were concordant for course type. Seven sets of twins were included (approximately 10% of the total), all were concordant for onset and course type (6 sets with pauciarticular, 1 set with polyarticular), and disease onset was separated by a mean of only 3.3 months. Within the onset and course types, the clinical disease, such as the female:male ratio, age at onset, and serologic findings, in ASPs resembled that which has been described in the literature. CONCLUSION: A higher than expected degree of concordance for onset type of JRA exists between sibpairs, indicating that genetic influences play a role. Affected sibs do not tend to develop their disease at approximately the same point in time, except for the twin sets. Clinical features of the disease within the various subtypes appear similar to those in non-ASP populations. PMID- 9365085 TI - Predictors of total body bone mineral density in non-corticosteroid-treated prepubertal children with juvenile rheumatoid arthritis. AB - OBJECTIVE: To determine the extent of significant osteopenia in prepubertal patients with juvenile rheumatoid arthritis (JRA) not treated with corticosteroids and to identify variables that are highly related to bone mineralization in this population. METHODS: In a cross-sectional study, 48 JRA patients and 25 healthy control subjects ages 4.6-11.0 years were evaluated. Total body bone mineral density (TB BMD) was determined by Hologic dual energy x ray absorptiometry. All patients were prepubertal (Tanner stage I or II) and had never taken corticosteroids. For comparison, JRA patients were divided into "low" TB BMD (Z score < or =-1) or "normal" TB BMD (Z score >-1). RESULTS: The overall mean +/- SD TB BMD scores did not differ between the JRA subjects (0.75 +/- 0.06 gm/cm2) and controls (0.73 +/- 0.07 gm/cm2; P > 0.30). However, 29.2% of the JRA patients had low TB BMD, whereas only 16% would be expected to have low TB BMD based on the standard normal distribution (goodness of fit chi(2) = 4.84, P = 0.01). The mean Z score for the JRA patients with low TB BMD was -1.43, and for those with normal TB BMD, it was 0.32. The JRA subjects with low TB BMD were significantly younger, had more active articular disease, greater physical function limitation, higher erythrocyte sedimentation rate, higher joint count severity score, lower body mass index, lower lean body mass, less participation in organized sports, and more protein and vitamin D in their diet compared with JRA patients with normal TB BMD (all P < 0.05). Using logistic regression, a model including age at JRA onset, Juvenile Arthritis Functional Assessment Report (JAFAR) score, triceps skin-fold percentiles, percentage US recommended daily allowance for dietary magnesium intake, and serum 1,25-dihydroxyvitamin D levels was able to accurately segregate 79.6% of the JRA subjects into either the low or normal TB BMD groups (chi(2) = 20.5, P = 0.001). CONCLUSION: This study demonstrated that in a mildly to moderately ill prepubertal JRA population that had never been exposed to corticosteroids, almost 30% had significantly low TB BMD. The patients with low TB BMD had more active and severe articular disease and greater physical function limitation. Disease-related parameters in JRA appear to exert a negative effect on bone mineralization even in prepubertal children, which can be demonstrated despite the exclusion of corticosteroid treated patients. PMID- 9365086 TI - Development of validated disease activity and damage indices for the juvenile idiopathic inflammatory myopathies: I. Physician, parent, and patient global assessments. Juvenile Dermatomyositis Disease Activity Collaborative Study Group. AB - OBJECTIVE: To determine the reliability, content validity, and responsiveness of physician global assessments of disease activity and damage in the juvenile idiopathic inflammatory myopathies (IIM), and to investigate concordance among physician, parent, and patient global ratings. METHODS: Sixteen pediatric rheumatologists rated 10 juvenile IIM paper patient cases for global disease activity and damage, and assessed the importance of 51 clinical and laboratory parameters in formulating their global assessments. Then, 117 juvenile IIM patients were enrolled in a protocol to examine the relationship between Likert and visual analog scale global assessments, their sensitivity to change, and the comparability of physician, parent, and patient global ratings. RESULTS: Pediatric rheumatologists demonstrated excellent interrater reliability in their global assessments of juvenile IIM disease activity and damage (97.7% and 94.7% agreement among raters, respectively), and agreed on a core set of clinical parameters in formulating their judgments. Likert scale ratings correlated with those on a visual analog scale, and both were comparable in responsiveness (standardized response means -0.56 for disease activity, 0.02 [Likert] and 0.14 [visual analog] for damage, measured over 8 months). Parent global ratings of disease activity correlated with physician assessments, but were not colinear (Spearman's correlation [r] = 0.41-0.45). Patient global disease activity assessments correlated with those done by parents (r = 0.57-0.84) and physicians (r = 0.37-0.63), but demonstrated less responsiveness (standardized response means -0.21 and -0.12, respectively, over 8 months). CONCLUSION: Physician global assessments of juvenile IIM disease activity and damage demonstrated high interrater reliability and were shown to be comprehensive measures. Both physician and parent disease activity assessments should be considered valuable as quantitative measures for evaluating therapeutic responses in juvenile IIM patients. PMID- 9365087 TI - The value of the Health Assessment Questionnaire and special patient-generated scales to demonstrate change in systemic sclerosis patients over time. AB - OBJECTIVE: To determine the validity and usefulness of a modified Health Assessment Questionnaire (HAQ) for measurement of disease status and changes in disease status over time in patients with systemic sclerosis (SSc). METHODS: Since 1985, 1,250 patients attending the University of Pittsburgh Scleroderma Clinic have completed a modified HAQ annually. In addition to the standard HAQ questions about disability, the questionnaire includes visual analog scales (VAS) to evaluate SSc organ system symptoms, Raynaud's phenomenon, gastrointestinal (GI) tract and lung involvement, pain, and overall disease severity. In this study, the disability index (DI) (from the HAQ) and the VAS scores (on a 0-3 scale) were compared with various clinical and laboratory features recorded within 3 months of administration of the HAQ and VAS, using t-tests and Spearman's correlation tests. RESULTS: The HAQ DI correlated directly with skin involvement, scleroderma heart or kidney disease, tendon friction rubs, hand contractures, and proximal muscle strength. Over time, the DI correlated with changes in skin score and was a good predictor of survival. There was a significant improvement in the DI during a 2-year time period in patients treated with D-penicillamine. The VAS for digital ulcers, GI symptoms, and lung symptoms correlated very closely with subjective and objective findings for these organ systems. The presence of new digital ulcers or improvement in digital ulcers showed significant associations with the Vascular scale, new GI symptoms or improvement in GI symptoms and institution of H2-blockers showed appropriate strong correlations with the GI scale, and changes in the forced vital capacity had an excellent correlation with the Lung scale (r = 0.58, P < 0.001). By Cox regression analysis, the HAQ DI was one of the best predictors of survival. CONCLUSION: These data provide convincing evidence that a self-administered questionnaire is an accurate and inexpensive tool to measure disease status changes in SSc. Prospective studies with the HAQ administered at regular intervals, as in controlled trials, should be performed to further assess the benefits and limitations of this instrument. PMID- 9365088 TI - Mediastinal mass and hilar adenopathy: rare thoracic manifestations of Wegener's granulomatosis. AB - OBJECTIVE: To assess the frequency and characteristics of hilar and mediastinal involvement in patients with Wegener's granulomatosis (WG). METHODS: A patient with WG presented with the unusual finding of a mediastinal mass, prompting a comprehensive review of 302 patient records from 2 WG registries to obtain evidence of hilar adenopathy or mediastinal masses. Clinic progress notes and findings of chest imaging studies (routine imaging and computed tomography) were reviewed for the presence of hilar lymphadenopathy, mediastinal masses, or mediastinal lymphadenopathy. All radiographs and surgical pathology specimens from these lesions were reviewed. RESULTS: Six examples of mediastinal or hilar involvement (2.0%) were identified among 302 patients with WG. Three of these 6 patients had mediastinal masses. One patient with a mediastinal mass also had mediastinal lymphadenopathy. Two of the patients with mediastinal masses had lung parenchymal lesions. The remaining 3 patients had enlarged hilar lymph nodes in addition to pulmonary parenchymal lesions. All of the patients were treated with corticosteroids and cytotoxic drugs. Followup information was available on all patients. Two patients died. In the remaining 4 patients, the mediastinal mass or hilar lymphadenopathy decreased in size or resolved after 2 months of immunosuppressive therapy. CONCLUSION: In the past, hilar adenopathy and/or mediastinal mass have been considered unlikely features of WG, and their presence has prompted consideration of an alternative diagnosis. Although this caution remains valuable, the present retrospective review of data from 2 large WG registries illustrates that such findings may rarely be a part of the spectrum of WG chest disease. Because these findings are uncommon, they necessitate consideration of a primary or concurrent infection or malignancy in the diagnostic evaluation. PMID- 9365090 TI - Localization of hepatitis C virus in cutaneous vasculitic lesions in patients with type II cryoglobulinemia. AB - OBJECTIVE: To investigate the role of hepatitis C virus (HCV) in the pathogenesis of the cutaneous vasculitis in patients with type II cryoglobulinemia. METHODS: Using in situ hybridization detection of HCV, we studied 6 test patients and various control subjects. Serum HCV was quantitated, cryoglobulins were analyzed by column chromatography at 37 degrees C, and low-density lipoprotein (LDL) receptors on keratinocytes were detected using LDL labeled with fluorescent dye. RESULTS: In the cutaneous vasculitic lesions from test patients, but not control subjects, the HCV virion was found in association with IgM and IgG. HCV alone was detected in some vessel walls, and in skin and ductal epithelium and vascular endothelium in inflamed, but not normal, skin. Cryoglobulins showed HCV, monomeric IgM, and monomeric IgG, with little or no immune complexes. The extent of the lesions correlated with levels of viremia. Up-regulation of LDL receptors on keratinocytes was detected in inflamed, but not normal, skin. CONCLUSION: HCV was present in the cutaneous vasculitic lesions, most likely in complexes with IgM and IgG formed in situ. These findings and the correlation of the severity of the rash with the level of viremia suggest that HCV plays a major role in the pathogenesis of cutaneous vasculitis in these patients and strengthens the rationale for antiviral drug therapy. The presence of HCV in keratinocytes and ductal epithelial and vascular endothelial cells may be the in vivo manifestation of endocytosis of HCV by the LDL receptors that has recently been demonstrated in vitro. The up-regulation of LDL receptors on keratinocytes in inflamed skin is consistent with this postulation. PMID- 9365089 TI - Anticardiolipin IgG subclasses: association of IgG2 with arterial and/or venous thrombosis. AB - OBJECTIVE: To determine whether the presence of anticardiolipin antibodies (aCL) of a specific IgG subclass is associated with clinical complications of the antiphospholipid antibody syndrome (APS) and whether polymorphisms of Fc receptors for IgG (FcgammaR) with differential binding preferences contribute to an increased risk of thrombotic complications. METHODS: In 60 patients with IgG aCL, we assessed clinical complications of the APS, measured the level of antibody activity, and determined the IgG subclass distribution of aCL by a modified enzyme-linked immunosorbent assay (ELISA) with murine anti-human IgG subclass monoclonal antibodies. Selective IgG subclass adsorption studies were performed to determine the relative contribution of specific IgG subclasses to overall aCL activity. Fcgamma receptor IIA (FcgammaRIIA) genotypes of aCL patients with thrombosis and of non-systemic lupus erythematosus controls were determined by polymerase chain reaction amplification of genomic DNA and allele specific probes. RESULTS: IgG2 aCL, detected in 75% of the patients, was the major subclass of aCL. Selective adsorption studies demonstrated that IgG2, in contrast to IgG1, was the predominant subclass responsible for aCL reactivity. IgG2 aCL was the only subclass associated with clinical complications, specifically, arterial and/or venous thrombosis (P < 0.04). The presence of FcgammaRIIA-H131, a receptor expressed on platelets, monocytes, and endothelial cells and the only human FcgammaR which efficiently recognizes IgG2, was associated with thrombosis in aCL patients. Among 45 high-titer (>40 GPL [IgG phospholipid] units) aCL patients with thrombosis, 40% were homozygous for FcgammaRIIA-H131, compared with 25% of disease-free controls (P = 0.042). CONCLUSION: While all 4 IgG subclasses are found in autoimmune aCL, only the presence of IgG2 is significantly associated with thrombotic complications. Reactivity in aCL ELISA is largely due to the presence of IgG2 in high-titer patients. The presence of IgG2 aCL, particularly in association with FcgammaRIIA H131, may be a useful clinical predictor of increased thrombotic risk in patients with autoimmune IgG aCL. Allelic variants of FcgammaRIIA with distinct capacities to interact with IgG subclasses provide a mechanism for genetic susceptibility to an autoantibody-induced prothrombotic state. PMID- 9365091 TI - Human retrovirus-5 proviral DNA is rarely detected in salivary gland biopsy tissues from patients with Sjogren's syndrome. AB - OBJECTIVE: To examine whether human retrovirus-5 (HRV-5) infection is associated with Sjogren's syndrome. METHODS: Salivary gland DNA was tested by nested polymerase chain reaction (PCR) for HRV-5 proviral DNA. Rigorous precautions were taken to prevent false-positive results from PCR contamination. Positive samples were confirmed by testing with an additional independent set of primers and were then sequenced. RESULTS: Ninety-two samples were examined (55 from Sjogren's syndrome patients, 37 from non-Sjogren's syndrome patients), 2 of which were positive. One was from a patient who had sicca symptoms but who did not satisfy the criteria for a diagnosis of Sjogren's syndrome. The other was from a patient with secondary Sjogren's syndrome. Owing to the extremely low virus load in minor salivary glands, the number of HRV-5-infected patients may be underestimated. In total, 3 different sequences of HRV-5 were identified which were 98% identical to the original sequence but which displayed variations between and within individuals. CONCLUSION: This is the first study to systematically seek a disease association with HRV-5, although with this method, an association with Sjogren's syndrome was not identified. PMID- 9365092 TI - Effects of inflammation and treatment on bone turnover and bone mass in polymyalgia rheumatica. AB - OBJECTIVE: Polymyalgia rheumatica (PMR) has an abrupt onset of inflammatory symptoms, making it a useful model for studying the effects of inflammation in bone. PMR requires corticosteroid treatment, which may itself have a detrimental effect on bone. This study used serially measured biochemical markers of bone turnover and bone density to address the relative contributions of systemic inflammation and corticosteroid therapy to bone loss. METHODS: Fifty untreated patients with PMR were randomized to receive oral prednisolone or intramuscular methylprednisolone. Biochemical bone markers (pyridinoline [PYR], deoxypyridinoline [DPYR], procollagen type I carboxy-terminal peptide [PICP]) and bone mineral density (BMD) were measured at baseline and at 6, 12, and 24 months. RESULTS: The median disease duration at presentation was 12 weeks (range 5-32 weeks). Levels of urinary crosslinks were increased in patients with untreated PMR compared with controls (PYR 74.9 +/- 30.0 nmoles/mmole creatinine, DPYR 14.6 +/- 6.4 nmoles/mmole creatinine [mean +/- SD]; P = 0.0001); the PICP level was normal (115.0 +/- 39.0 microg/liter). With treatment, the crosslinks levels fell and PICP levels rose within 6 months (P = 0.01). Bone resorption (PYR) correlated with untreated disease activity (erythrocyte sedimentation rate [ESR]) (r = 0.5, P = 0.003) and with interleukin-6 levels (r = 0.48, P = 0.05). There was a significant reduction in BMD of both the hip and the spine after 12 months of treatment (P = 0.0002), with no difference between treatment groups. As the steroid dosage was reduced, bone mass improved. Initial ESR influenced the percent change in BMD at 1 year (r = 0.35, P = 0.05), while cumulative steroid dose, mean ESR, and type of steroid used did not. CONCLUSION: Inflammation in PMR increases bone resorption and appears to have a more detrimental effect on bone than does low-dose corticosteroid. If corticosteroids can be tapered and discontinued, bone loss in PMR can be a transient phenomenon. PMID- 9365093 TI - Induction of interleukin-1 and subsequent tissue factor expression by anti proteinase 3 antibodies in human umbilical vein endothelial cells. AB - OBJECTIVE: To assess the ability of anti-proteinase 3 (anti-PR3) classic antineutrophil cytoplasmic antibodies (cANCA) to stimulate endothelial expression of tissue factor (TF), which is the main initiator of the coagulation cascade that can lead to endothelial injury and thrombosis in patients with Wegener's granulomatosis. METHODS: Human umbilical vein endothelial cells (HUVEC) were grown to confluence and stimulated with affinity-purified anti-PR3 antibodies, Igs from healthy subjects, and endotoxin (lipopolysaccharide) as positive control. RESULTS: TF activity was generated in anti-PR3-stimulated cells, as shown by a chromogenic test. This activity was inhibited by specific anti-TF antibodies. TF messenger RNA (mRNA) was found in anti-PR3-stimulated cells, as detected by reverse transcriptase-polymerase chain reaction, but not in cells stimulated with irrelevant human Igs or Igs from normal control sera. TF expression reached maximum levels 12 hours after exposure to the anti-PR3 cANCA, and did not require complement. TF mRNA expression was inhibited by cycloheximide, suggesting a requirement for protein synthesis. When added to the incubation medium, interleukin-1 (IL-1) receptor antagonist inhibited the induced TF mRNA expression, suggesting that cANCA-stimulated cells initiate IL-1 synthesis. Moreover, cANCA induced IL-1alpha mRNA before TF mRNA. CONCLUSION: This study showed that anti-PR3 treatment of HUVEC induces sequential expression of IL-1alpha mRNA and TF mRNA, as well as their corresponding proteins. Both proteins could have pathogenic roles in the vasculitic process, since TF is the main initiator of the coagulation cascade. PMID- 9365094 TI - In vitro induction of proinflammatory cytokine secretion by juvenile rheumatoid arthritis synovial fluid immune complexes. AB - OBJECTIVE: To characterize juvenile rheumatoid arthritis synovial fluid (SF) immune complexes and to examine their interaction with leukocytes. METHODS: SF immunoglobulin-containing fractions were prepared by sequential chromatography on protein A and Sephacryl 300. Fractions were subdivided according to molecular weight, characterized for immunoglobulin and complement content, and incubated with either promonocytic U937 cells or normal human peripheral blood mononuclear cells (PBMC). RESULTS: High molecular weight SF immunoglobulin-containing fractions stimulated the release of interleukin-1beta (IL-1beta) from U937 cells. These same complexes stimulated tumor necrosis factor alpha (TNFalpha), IL-1beta, IL-6, IL-8, and granulocyte-macrophage colony-stimulating factor (GM-CSF) from PBMC. Lower molecular weight material was less efficient in inducing any of the cytokines. TNFalpha and IL-1beta were the earliest of the messenger RNAs examined to be induced by the high molecular weight complexes. However, the secretion of IL-6, IL-8, and GM-CSF stimulated by the complexes was not completely dependent upon the secretion of IL-1beta. Addition of IL-1 receptor antagonist to the cell cultures reduced GM-CSF and IL-6 production by 40% and IL-8 production by 25% in PBMC. CONCLUSION: SF immunoglobulin fractions contain immune complexes that vary in size, composition, and phlogistic potential. High molecular weight complexes are capable of inducing a spectrum of proinflammatory cytokines, all of which have been implicated in the pathogenesis of rheumatic disease. PMID- 9365095 TI - HLA-B27-derived peptides as autoantigens for T lymphocytes in ankylosing spondylitis. AB - OBJECTIVE: To study whether peptides derived from the HLA-B27 molecule sequence can stimulate peripheral blood T lymphocytes (PBL) from patients with HLA-B27 associated spondylarthropathies. METHODS: PBL from 55 HLA-B27+ patients with ankylosing spondylitis (AS), 28 HLA-B27+ patients with other spondylarthropathies, 7 rheumatoid arthritis patients, and 30 HLA-B27+ and 22 HLA B27- healthy controls were tested in lymphocyte proliferation assays with 4 synthetic peptides derived from the HLA-B*2705 molecule. RESULTS: A 13-mer peptide (B27PA) induced significant proliferative responses in 17 of the 55 AS patients (stimulation index [SI] 2.5-17.5), as well as in 3 of the HLA-B27+ healthy controls (SI 2.5-9.8). Another 13-mer peptide (B27PC) induced PBL proliferation (SI 2.7-5.5) in 10 AS patients and in some donors of the control groups. In B27PA-specific T cell lines, an expansion of cells positive for the gamma/delta T cell receptor could be demonstrated. CONCLUSION: These results indicate that HLA-B27-derived peptides can be recognized as autoantigens by PBL of HLA-B27+ AS patients and B27+ healthy controls. Recent infections preceding the manifestation of AS may be involved in this process of anti-self major histocompatibility complex reactivity. PMID- 9365096 TI - Effects of pulse methylprednisolone on bone and marrow tissues: corticosteroid induced osteonecrosis in rabbits. AB - OBJECTIVE: To investigate the effects of pulse methylprednisolone acetate on bone and bone marrow tissues and to clarify the causal factors of corticosteroid induced osteonecrosis (ON) by using an experimental animal model. METHODS: Male adult Japanese white rabbits were injected once with 20 mg/kg of methylprednisolone into the right gluteus medius muscle. Seven rabbits were killed at 4 weeks, 4 at 6 weeks, 4 at 8 weeks, and 6 at 10 weeks. Both histopathologic and hematologic studies were performed every week. RESULTS: By 4 weeks after the steroid injection, 43% of the rabbits studied had developed multifocal ON lesions in the femur and/or humerus. In 1 rabbit, a thrombus was detected in an arteriole adjacent to the necrotic area at 4 weeks. After 6 weeks, there was also progressive histologic evidence of revascularization, with granulation tissue, and osteoblastic repair, with appositional bone formation. Hyperlipemia, fatty liver, and intraosseous fat embolism were observed in conjunction with thrombocytopenia and hypofibrinogenemia. CONCLUSION: A single injection of high-dose corticosteroids was found to be capable of inducing thrombocytopenia, hypofibrinogenemia, and hyperlipemia with multifocal ON in several bones. PMID- 9365098 TI - Correlation of morphologic and biochemical changes in the natural history of spontaneous osteoarthrosis in guinea pigs. AB - OBJECTIVE: To study how the concentrations of proteoglycans (PGs) and collagen change in various parts of tibial articular cartilage during aging, and to evaluate the development of spontaneous osteoarthrosis (OA) in guinea pigs. METHODS: PGs were extracted from guinea pig cartilage samples using 4M guanidine hydrochloride, and the amount of hydroxyproline was determined in the extraction remainder. The molecular size and aggregation of PGs were analyzed by electrophoresis, and the glycosaminoglycan composition was assessed by high performance liquid chromatography. RESULTS: The PG concentration was proportional to the load distribution. However, when OA became histologically manifest, the PG concentration decreased by 50% (from a mean of 44 microg to 22 microg per mg fresh tissue) and the collagen level decreased by 40% (from a mean of 17 microg to 10 microg per mg fresh tissue), while the proportion of water increased by 13% (from a mean of 710 mg to 800 mg per mg fresh tissue). CONCLUSION: Unmineralized cartilage can, within physiologic load limits, respond to increased mechanical demands by increasing the PG and collagen concentrations. Beyond a certain limit, however, the cartilage can no longer compensate for further increases in stress, which results in cartilage degeneration and losses of matrix constituents. These losses seemed to appear earlier in the disease process than has been described in previous animal models of secondary OA. PMID- 9365097 TI - Osteoarthritic lesions: involvement of three different collagenases. AB - OBJECTIVE: To assess the presence of fibroblast collagenase (MMP-1), neutrophil collagenase (MMP-8), and collagenase 3 (MMP-13) in osteoarthritic (OA) cartilage, with particular emphasis on areas of macroscopic cartilage erosion. METHODS: Messenger RNA (mRNA) levels were assessed by reverse transcriptase-polymerase chain reaction (RT-PCR), in situ hybridization, and Northern blot analysis. RESULTS: MMP-1 and MMP-13 were expressed at higher levels by OA chondrocytes than by normal chondrocytes. In addition, mRNA for MMP-8 was present in OA cartilage but not normal cartilage by PCR and Northern blot analyses. Chondrocytes from areas surrounding the OA lesion expressed greater quantities of MMP-1 and MMP-13 compared with normal chondrocytes, suggesting local modulation by mechanical and inflammatory factors. Tumor necrosis factor alpha stimulated the expression of all 3 collagenases. Retinoic acid, an agent which induces autodigestion of cartilage in vitro, stimulated only the expression of MMP-13. CONCLUSION: These findings suggest a key role of MMP-13 and MMP-8, as well as MMP-1 in osteoarthritis. PMID- 9365100 TI - Clostridium difficile-associated diarrhea in rheumatoid arthritis patients who are receiving therapy with low-dose chlorambucil. PMID- 9365101 TI - Laboratory abnormalities and systemic lupus erythematosus flare: comment on the article by Esdaile et al. PMID- 9365099 TI - Molecular diagnosis of Ureaplasma urealyticum in an immunocompetent patient with destructive reactive polyarthritis. AB - Polymerase chain reaction (PCR) amplification, which is a useful method for detecting infectious agents in joints, has potential utility in the molecular diagnosis of venereal-associated arthritis. Among pathogens detected by this technique, Ureaplasma urealyticum, which is primarily associated with reactive arthritis (ReA), is also implicated in septic arthritis in immunocompromised patients. We report here a case of destructive polyarthritis, initially suggestive of septic arthritis, in an immunocompetent patient whose PCR positivity for U. urealyticum DNA in one joint, in conjunction with the disease outcome and histologic findings, led to the diagnosis of destructive ReA. PMID- 9365102 TI - Patient variation in the correlation between laboratory abnormalities and future lupus flares: comment on the article by Esdaile et al. PMID- 9365103 TI - Use of heat inactivation in assays for antibodies to beta2-glycoprotein I and anticardiolipin: comment on the concise communication by Roubey et al. PMID- 9365104 TI - Incidence of antinuclear antibodies in Japanese patients with chronic fatigue syndrome. PMID- 9365105 TI - Uncompensated cervical traction as a possible cause of symptoms in women with breast implants: comment on the article by Buskila et al. PMID- 9365106 TI - 100 years of frontal sinus surgery. AB - The surgical treatment of chronic inflammatory frontal sinus disease over the past century has varied between intranasal and external procedures. There has been constant modification of these techniques; however, a single approach that will lead to relief of symptoms, eradication of disease with preservation of function, and a minimum of deformity has not yet been attained. The functional theory of sinus disease, the evolution of endoscopic techniques, and data provided by the computed tomography scan have renewed our interest in the anatomy of the lateral nasal wall and endonasal surgery. Extensive literature exists concerning the results of ethmoid, maxillary, and sphenoid endoscopic surgery. However, detailed information is not available on the treatment of inflammatory frontal sinusitis. The author presents the results of a retrospective analysis of a series of 101 patients with inflammatory frontal sinusitis who underwent endoscopic surgery that included the frontoethmoid complex. Results for improvement of symptoms as well as endoscopic findings are presented. Relief of symptoms was significant but did not correlate with postoperative endoscopic findings in patients with hyperplastic and polypoid sinusitis. Patients with anterior ethmoid cell encroachment on the frontal sinus outflow tract had a positive correlation between improvement of symptoms and postoperative endoscopic findings. Frontal recess stenosis was associated with a poor outcome. Anatomic obstruction of the frontonasal duct is most consistent with the functional theory of sinusitis. PMID- 9365107 TI - 1997 Dolph Adams Awards. PMID- 9365108 TI - The role of CXC chemokines in the regulation of angiogenesis in non-small cell lung cancer. AB - Angiogenesis is a critical component of tumor biology. In recent years newer techniques of cell and molecular biology have led to important advances in our understanding of this process. The regulation of angiogenesis depends on a balance between the activity of local factors that promote (angiogenic factors) or inhibit (angiostatic factors) neovascularization. Nowhere is this paradigm of a balance more apparent than in the study of tumor-associated angiogenesis. Tumors promote angiogenesis through a combination of overexpression of angiogenic factors and local inhibition of angiostatic factors. This strategy leads to an angiogenic environment that promotes tumor growth and metastases. Our laboratory has focused studies on the role of the CXC chemokine family in the regulation of angiogenesis by non-small cell lung cancer (NSCLC). In this article, we review our findings that the CXC chemokine family is composed of members that are either angiogenic or angiostatic. We have found that in NSCLC an imbalance exists in the expression of these factors that favors tumor-derived angiogenesis, and therefore tumor growth and metastases. Furthermore, when this imbalance is corrected to reduce the presence of angiogenic factors or increase the presence of angiostatic factors, tumor growth and metastases are reduced. PMID- 9365109 TI - Granulocyte chemotactic protein-2 and related CXC chemokines: from gene regulation to receptor usage. AB - Chemokines contribute to the inflammatory response by selective attraction of various leukocytic cell types. Human GCP-2 was originally identified by amino acid sequence analysis as a CXC chemokine co-produced with IL-8 by osteosarcoma cells. Furthermore, the complete coding domain of human GCP-2 was disclosed by means of RT-PCR. Similarly, mouse GCP-2 was isolated from fibroblastoid and epithelial cells and completely identified by sequence analysis. Human and mouse GCP-2 share 61% identical amino acids. Both chemokines occur as multiple NH2 terminally truncated forms. The shorter forms of mouse, but not those of human, GCP-2 showed a higher neutrophil chemotactic potency and gelatinase B releasing capacity. Mouse GCP-2 was a more potent neutrophil activator than human GCP-2, natural mouse KC, and MIP-2. Human GCP-2 was not chemotactic for monocytes, lymphocytes, or eosinophils. Quantitative studies of mRNA expression in diploid fibroblasts revealed GCP-2 induction by IL-1beta. Human GCP-2 induced [Ca2+]i increase in neutrophils, which was reciprocally desensitized by IL-8, GROalpha, and ENA-78. Human GCP-2 induced [Ca2+]i increases and chemotactic responses in both CXCR1- and CXCR2-transfected cells. Finally, GCP-2 provoked neutrophil accumulation and plasma extravasation in rabbit skin. In humans, GCP-2 complements the activity of IL-8 as neutrophil chemoattractant and activator but it constitutes a major neutrophil chemokine in the mouse. GCP-2 induces neutrophil chemotaxis and activation but it might also contribute to detrimental tissue damage in sepsis, acute respiratory distress syndrome, acute hypersensitivity reactions, and autoimmune diseases. It might also influence the invasive capacity of GCP-2-secreting tumor cells. PMID- 9365110 TI - Secreted poxvirus chemokine binding proteins. AB - Poxviruses encode a variety of immunomodulatory proteins that subvert the cytokine networks of infected hosts. Myxoma virus, a poxvirus pathogen of rabbits, expresses two distinct 35- to 40-kDa secreted glycoproteins that bind a broad spectrum of chemokines. The first of these, designated M-T7, is encoded by the T7 gene and is the first example of what is here referred to as type-I chemokine binding protein (CBP-I). M-T7 was initially discovered as a secreted viral homologue of cellular interferon-gamma receptor but binding studies indicate that purified M-T7 protein also interacts with members of the CXC, CC, and C chemokine families through the conserved heparin-binding domains. The second myxoma protein, M-T1, also called CBP-II, is a member of a larger superfamily of poxvirus proteins that includes related secreted 35-kDa proteins encoded by a wide variety of orthopoxviruses. Deletion analysis of either CBP-I or -II genes within recombinant poxvirus constructs revealed profound alterations in the trafficking of infiltrating leukocytes into virus-infected lesions. It is proposed that the interaction of CBP-I with the conserved heparin-binding domains found on most chemokines represents a novel mechanism for altering multiple chemokine functions in vivo. In summary, CBP-I and CBP-II are the first examples of secreted virus proteins that bind to multiple chemokine family members as part of a strategy to prevent the early phase of inflammatory cell migration into virus-infected tissues. PMID- 9365111 TI - In vivo properties of monocyte chemoattractant protein-1. AB - Monocyte chemoattractant protein-1 (MCP-1) attracts monocytes, memory T lymphocytes, and natural killer (NK) cells in vitro. Its expression has been documented in disorders characterized by mononuclear cell infiltrates, suggesting that it may contribute to the inflammatory component of such diseases as atherosclerosis, multiple sclerosis, or rheumatoid arthritis. To prove a causal association, the in vivo properties of MCP-1 must be understood. Several lines of transgenic mice have been constructed to address this question. A transgenic line in which MCP-1 expression is controlled by the MMTV-LTR expressed high levels of MCP-1 in multiple organs but showed no evidence for monocyte infiltration. Instead, these mice were more susceptible to infection by the intracellular pathogens, Listeria monocytogenes and Mycobacterium tuberculosis. These mice had high serum levels of MCP-1, suggesting that their circulating monocytes may have been desensitized or that MCP-1 stimulated a Th2-dominant response. In contrast, another model in which MCP-1 expression was controlled by the insulin promoter demonstrated a monocytic infiltrate in pancreatic islets. These results indicate that MCP-1 expression at low levels in an anatomically confined area results in monocyte infiltration, suggesting that when properly expressed, MCP-1's in vitro properties are reproduced in vivo. This justifies the examination of MCP-1 deficient mice in disease models in order to explore MCP-1's role in pathogenesis. PMID- 9365112 TI - Pivotal role of interleukin-8 in the acute respiratory distress syndrome and cerebral reperfusion injury. AB - Neutrophil recruitment is one of the hallmarks of acute inflammation. A potent neutrophil chemotactic and activating factor, interleukin-8 (IL-8), has been demonstrated to be elevated in body fluids in various human diseases and experimental animal models. Recent investigations on animal disease models using blocking antibodies to IL-8 have revealed the essential involvement of IL-8 in acute inflammation. We previously reported that the administration of a neutralizing antibody against IL-8 prevented the neutrophil infiltration and neutrophil-mediated tissue injury in several animal studies. In addition, we have recently demonstrated that anti-IL-8 treatment is also effective in prevention of two models that are very relevant to clinical situations: cerebral reperfusion injury and endotoxemia-induced acute respiratory distress syndrome-like lung injury. These results further support the hypothesis that IL-8 has a pivotal role and is a novel target for therapeutic intervention in neutrophil-mediated injury. PMID- 9365114 TI - Sequence similarities of a subgroup of CXC chemokines related to murine LIX: implications for the interpretation of evolutionary relationships among chemokines. AB - The murine CXC chemokine LIX has distinctive sequence features that suggest it is a novel chemokine. Among known human chemokines, ENA-78 and GCP-2 are the two most closely related to LIX. We have recently cloned the human GCP-2 gene. Phylogenetic analysis shows that the LIX coding region is more distant from both human GCP-2 and ENA-78 than is porcine AMCF-II, the chemokine with greatest sequence similarity to LIX. Human GCP-2 and ENA-78 have very high nucleotide similarity in non-coding as well as coding sequences, which suggests that these genes are the result of an evolutionarily recent gene duplication event. If this duplication occurred during primate evolution, then non-primate species may have only a single chemokine corresponding to this pair of human genes. This example shows that a one-to-one genetic correspondence does not necessarily exist between all the chemokine genes in two different species. These observations may have important implications for other chemokines that belong to clusters of closely related genes. PMID- 9365113 TI - Mechanism and biological significance of constitutive expression of MGSA/GRO chemokines in malignant melanoma tumor progression. AB - By reverse transcriptase-polymerase chain reaction, enzyme-linked immunosorbent assay, and immunohistochemistry, MGSA-alpha, -beta, -gamma, and CXCR2 mRNA expression and proteins are detected in 7 out of 10 human melanoma lesions. The biological consequence of constitutive expression of the MGSA/GRO chemokine in immortalized melanocytes was tested in SCID and nude mouse models. Continuous expression of MGSA/GRO-alpha, -beta, or -gamma in immortalized melan-a mouse melanocytes results in nearly 100% tumor formation for each of the clones tested, whereas clones expressing only the neomycin resistance vector form tumors <10% of the time. Moreover, antibodies to the MGSA/GRO proteins slow or inhibit the formation of tumors in the SCID mouse model and block the angiogenic response to conditioned medium from the tumor-producing clones. Transcription of the MGSA/GRO chemokines is regulated by an enhancesome-like complex comprised of the nuclear factor-kappaB (NF-kappaB), HMG(I)Y, IUR, and Sp1 elements. In Hs294T melanoma cells the half life of the IKB protein is shortened in comparison to normal retinal epithelial cells, facilitating the endogenous nuclear localization of NF kappaB. We propose that this endogenous nuclear NF-kappaB, working in concert with the 115-kDa IUR-binding factor, promotes constitutive expression of MGSA/GRO genes. PMID- 9365115 TI - Regulation and function of the CXC chemokine ENA-78 in monocytes and its role in disease. AB - Epithelial neutrophil-activating protein 78 (ENA-78) is a member of the CXC chemokines and acts as a potent chemoattractant and activator of neutrophil function. On stimulation in vitro, ENA-78 is highly expressed in many cell types. ENA-78 protein levels are strongly elevated in synovial fluid and blood of patients with rheumatoid arthritis. By in situ hybridization and immunofluorescence staining, ENA-78 has been recognized as a major CXC chemokine expressed in epithelial cells of the intestinal mucosa of patients with Crohn's disease, ulcerative colitis, and acute appendicitis. A high expression of ENA-78 and interleukin-8 (IL-8) was also observed in the exocrine tissue of patients with chronic pancreatitis (CP). It is interesting to note that expression of IP 10, MIP-1alpha, and MCP-1 is high in healthy pancreatic tissue but low in tissue of patients with CP, suggesting a mutually exclusive expression of the ELR-CXC vs. non-ELR-CXC/CC chemokines. High-resolution studies of intracellular chemokines has revealed specific immunoreactivity for ENA-78 associated with the endoplasmic reticulum of many cell types. In contrast, GROalpha immunoreactivity was exclusively localized in the nucleus. Despite their common effects on neutrophil functions, the differential intracellular localization of ENA-78 and GROalpha suggests additional roles for these two chemokines in normal cell biology. PMID- 9365116 TI - Cell-to-cell and cell-to-matrix interactions mediate chemokine expression: an important component of the inflammatory lesion. AB - Although many studies have characterized soluble factors that stimulate or inhibit chemokine secretion, in this review we focus on the event of cellular adhesion as a novel mechanism for stimulating chemokine expression. Recent work has demonstrated chemokine expression following cell-to-cell and cell-to-matrix adhesion. The specificity of this finding was demonstrated utilizing various techniques that illustrate that adhesion, and not a soluble stimulus, is in some cases responsible for initiating or augmenting chemokine expression. For example, co-cultures of peripheral blood monocytes and endothelial cells secreted elevated levels of IL-8 and MCP-1 compared with either cell type alone. When co-cultured in transwells, this effect was significantly attenuated. In other experiments, neutralizing monoclonal antibodies to various adhesion molecules inhibited chemokine expression. The effects of adhesion were not limited to leukocytes. Both immune and non-immune cell types were evaluated as potential sources of adhesion-mediated chemokine expression. Not suprisingly, expression of some chemokines was associated with adhesion, whereas others were not, supporting the notion that adhesion differentially signals chemokine secretion during the inflammatory response. We hypothesize that as a recruited leukocyte encounters different adhesion substrates such as endothelial cells, basement membrane, extracellular matrix, and fibroblasts, the expression of chemokines from both the leukocyte and the substrate may be initiated, inhibited, or augmented. Careful characterization of the contribution of adhesion to regulation of chemokine expression will provide insight into the pathogenesis of many human diseases where chemokines have a central role. PMID- 9365117 TI - Role of the monocyte chemoattractant protein and eotaxin subfamily of chemokines in allergic inflammation. AB - Allergic inflammation is characterized by the tissue accumulation and activation of leukocytes rich in eosinophils. During these responses, there is marked induction of specific chemokines that are involved in regulating the recruitment and activation of these inflammatory cells. A subfamily of CC (or beta) chemokines composed of macrophage chemoattractant proteins (MCP) and eotaxin have emerged as cytokines involved in the recruitment and activation of the cells seen in allergic reactions. We now show that these chemokines are strikingly related in chromosomal location, gene structure, primary protein sequence, biological activity, and receptor usage. We also show that these chemokines are differentially regulated in human and animal models of allergic disease and perform distinct roles in vivo. We propose that this subfamily of chemokines plays a fundamental role in the development of allergic responses. PMID- 9365118 TI - Novel lymphocyte-specific CC chemokines and their receptors. AB - By using a cloning method termed the signal sequence trap as well as by searching for chemokine homologous sequences in the database of expressed sequence tags, cDNA fragments potentially encoding novel CC chemokines were initially identified. Using these sequences, we have cloned five novel human CC chemokines termed TARC, LARC, ELC, SLC, and PARC. These chemokines are constitutively expressed especially in some lymphoid tissues with individually unique expression patterns. The recombinant proteins are all found to be selectively chemotactic for lymphocytes but not for monocytes or neutrophils. Each chemokine appears to interact with a class of receptors on lymphocytes that is not shared by any other chemokines so far tested. Furthermore, we have identified CCR4 as the specific receptor for TARC, GPR-CY4/DRY6/CKR-L3/STRL22 as that for LARC (CCR6), and EBI1/BLR2 as that for ELC (CCR7). Only the gene for PARC is mapped to the traditional CC chemokine gene cluster at chromosome 17q11.2, whereas those for TARC, LARC, ELC, and SLC are localized at different loci. Collectively, these five CC chemokines may constitute a new category of CC chemokines that are involved in trafficking and homing of particular subsets of lymphocytes in particular lymphoid tissue microenvironments. PMID- 9365119 TI - Chemokines in neurological disease models: correlation between chemokine expression patterns and inflammatory pathology. AB - We have recently determined chemokine expression profiles in a variety of models of neural trauma and immune-inflammation. The results indicate the following: (1) Chemokine expression in posttraumatic inflammation is generally restricted to the monocyte chemoattractant MCP-1, and occurs before hematogenous cell entry into neural tissues. Therefore MCP-1 is an excellent candidate for a mediator of leukocyte recruitment in these settings. (2) Chemokine expression in immune inflammation is diverse and includes both alpha- and beta-chemokines. Chemokine production can be attributed to parenchymal and infiltrating cell populations. Early signs of inflammation precede chemokine expression, which is believed to exert the crucial function of amplifying the immune-mediated inflammatory reaction. These observations provide a basis for evaluating model neurological disorders in transgenic mice that express chemokines ectopically or in mice that are deficient in chemokine ligands or receptors as a consequence of gene targeting. Ultimately, a clear definition of roles of chemokines and their receptors in neurological diseases will suggest rational intervention. PMID- 9365120 TI - Regulation of CCR2 chemokine receptor mRNA stability. AB - During inflammatory and immunological responses, leukocytes respond to external stimuli by altering the stability of cytokine and cytokine receptor messages. Change in message stability is an effective mechanism for rapidly regulating steady state levels of mRNA. Cytokine messages containing A-U-rich elements located in the 3' untranslated region (ARE) are the best studied examples of this process. AREs have been shown to act as targeting motifs for degradation of cytokine and transcription factor messages. We have recently observed that the interleukin-8 (IL-8) receptor messages, IL-8RA and B (CXCR1 and CXCR2), also undergo changes in stability in response to the inflammatory stimulator lipopolysaccharide (LPS). To determine whether regulation of message stability is a common mechanism for modulation of chemokine receptor mRNA we explored whether the stability of the CC chemokine receptor message for CCR2 (monocyte chemotactic protein-1 receptor) is also regulated by LPS. We found that LPS induces a rapid loss of steady state levels of CCR2 message through message degradation. Furthermore, LPS stimulated the decay of Poly(A) CCR2 mRNA faster than total CCR2 RNA, indicating that deadenylation is the first step in LPS-induced CCR2 RNA degradation. We conclude from these experiments that LPS stimulates the rapid degradation of CCR2 messages through a two-step process, deadenylation followed by degradation of the message body. In contrast to the results obtained for CCR2 mRNA, macrophage inflammatory protein-1alpha messages, which contain an ARE motif, were stabilized by LPS stimulation, indicating that chemokine and chemokine receptor mRNA stability are regulated by different and opposing mechanisms. PMID- 9365121 TI - Eotaxin influences the development of embryonic hematopoietic progenitors in the mouse. AB - Eotaxin is a potent chemoattractant for eosinophils during inflammation and allergic reactions in the adult, but its role during development has not been studied. We report that eotaxin and its receptor, CCR-3, are expressed by embryonic tissues responsible for blood development, including the yolk sac, fetal liver, and fetal blood. We also found that eotaxin acts synergistically with stem cell factor (SCF) to accelerate the differentiation of embryonic mast cell progenitors and to promote the growth of Mac-1+/Gr-1- cells from progenitors isolated at 10-12 days of gestation. This response is diminished by Pertussis toxin, the Gi alpha inhibitor. These studies suggest that eotaxin is involved in the growth of myeloid cell progenitors and the differentiation of mast cells during embryogenic development. PMID- 9365122 TI - Cloning and functional characterization of a novel human CC chemokine that binds to the CCR3 receptor and activates human eosinophils. AB - Eotaxin has been found to bind exclusively to a single chemokine receptor, CCR3. Using expression sequence tag screening of an activated monocyte library, a second chemokine has been identified; it was expressed and purified from a Drosophila cell culture system and appears to only activate CCR3. Eotaxin-2, MPIF 2, or CKbeta-6, is a human CC chemokine with low amino acid sequence identity to other chemokines. Eotaxin-2 promotes chemotaxis and Ca2+ mobilization in human eosinophils but not in neutrophils or monocytes. Cross-desensitization calcium mobilization experiments using purified eosinophils indicate that eotaxin and MCP 4, but not RANTES, MIP-1alpha, or MCP-3, can completely cross-desensitize the calcium response to eotaxin-2 on these cells, indicating that eotaxin-2 shares the same receptor used by eotaxin and MCP-4. Eotaxin-2 was the most potent eosinophil chemoattractant of all the chemokines tested. Eotaxin-2 also displaced 125I-eotaxin bound to the cloned CCR3 stably expressed in CHO cells (CHO-CCR3) and to freshly isolated human eosinophils with affinities similar to eotaxin and MCP-4. 125I-Eotaxin-2 binds with high affinity to eosinophils and both eotaxin and cold eotaxin-2 displace the ligand with equal affinity. Eotaxin and eotaxin-2 promote a Ca2+ transient in RBL-2H3 cells stably transfected with CCR3 (RBL-2H3 CCR3) and both ligands cross-desensitized the response of the other but not the response to LTD4. The data indicate that eotaxin-2 is a potent eosinophil chemotactic chemokine exerting its activity solely through the CCR3 receptor. PMID- 9365123 TI - Role of MCP-1 and RANTES in inflammation and progression to fibrosis during murine crescentic nephritis. AB - The involvement of chemokines in inflammation is well established but their functional role in disease progression, and particularly in the development of fibrosis, is not yet understood. We have investigated the functional role that the chemokines monocyte chemotactic protein-1 (MCP-1) and RANTES play in inflammation and the progression to fibrosis during crescentic nephritis. During this disease inflammatory infiltrates are observed within glomeruli and interstitium in conjunction with increased expression of MCP-1 and RANTES and a decrease in renal function. Disease progression is marked by formation of glomerular crescents and the deposition of type I collagen. Blocking the function of MCP-1 or RANTES resulted in significant decreases in proteinuria as well as numbers of infiltrating leukocytes, indicating that both MCP-1 and RANTES play an important role in the inflammatory phase of crescentic nephritis. In particular, neutralization of MCP-1, but not RANTES, resulted in a dramatic decrease in glomerular crescent formation and deposition of type I collagen. These results highlight a novel role for MCP-1 in crescent formation and development of interstitial fibrosis and indicate that in addition to recruiting inflammatory cells this chemokine is critically involved in irreversible tissue damage. PMID- 9365124 TI - MIP-1alpha and MCP-1 differentially regulate acute and relapsing autoimmune encephalomyelitis as well as Th1/Th2 lymphocyte differentiation. AB - Chemokines are a family of small-molecular-weight cytokines that induce chemotaxis and chemokinesis of leukocytes. These molecules are ligands for seven transmembrane, G-protein-linked receptors and are known to activate integrins on the surface of leukocytes and other cells as well as induce a number of signaling events. They play a significant role in the migration of leukocytes from blood into tissue during inflammatory processes. We tested the role of chemokines in experimental autoimmune encephalomyelitis (EAE) and found that macrophage inflammatory protein-1alpha (MIP-1alpha) correlated with acute disease development, whereas monocyte chemotactic protein-1 (MCP-1) did not. In contrast, MCP-1 production in the central nervous system correlated with relapsing EAE development. Moreover, anti-MIP-1alpha, but not anti-MCP-1, inhibited development of acute but not relapsing EAE, whereas anti-MCP-1 significantly reduced the severity of relapsing EAE. To test the effects of chemokines on the differentiation of naive T cells, TCR transgenic splenic T cells (Tg+ T cells) from DO11.10 OVA TCR transgenic mice were used as a source of Th0 cells and were stimulated with specific anti-clonotypic monoclonal antibodies in the presence of MIP-1alpha, MCP-1, or controls. MIP-1alpha drove Th0 cells to differentiate to Th1, whereas MCP-1 drove Th0 cells to differentiate to Th2. Similarly, MCP-1, but not MIP-1alpha significantly inhibited the adoptive transfer of EAE when included in in vitro activation cultures, further suggesting a regulatory anti inflammatory property. These results suggest a differential role for CC chemokines in the development and activation of T cells during autoimmune inflammatory diseases. PMID- 9365125 TI - Effect of mast cell deficiency and leukotriene inhibition on the influx of eosinophils induced by eotaxin. AB - Eosinophils are believed to be important cells in the pathogenesis of asthma and allergic disease. Mast cells and leukotrienes may play a role in eosinophil recruitment. Eotaxin was recently described as a specific chemoattractant for eosinophils. Therefore we examined the effects of eotaxin on eosinophil flux in the mast cell-deficient WBB6F1/J-KitW/ KitW-v (W/Wv) mice and in mice treated with zileuton or ABT-761, specific 5-lipoxygenase inhibitors. Mice were injected intraperitoneally with eotaxin and at various times later the peritoneal cavities were lavaged and cell populations determined. Murine recombinant eotaxin induced a dose-dependent increase in eosinophils, which reached a maximum at 1-2 h and subsided at 4 h in both BALB/c and W/WV littermate control mice (no other cell population was altered). However, in eotaxin-injected W/Wv mice, the peak of eosinophil influx was delayed, peaking at 2 h, and a lower number of eosinophils was seen. The specific lipoxygenase inhibitors zileuton and ABT-761 given 30 min before eotaxin caused a 63-79% reduction in the level of eosinophils seen in the lavage fluid. These data suggest that eotaxin may either be activating eosinophils to release leukotrienes or making them more responsive to leukotrienes. In addition, mast cells may be playing a role in the amplification of the eotaxin effect. PMID- 9365126 TI - Small intestinal transplantation for irreversible intestinal failure in children. PMID- 9365127 TI - An atypical presentation for primary sclerosing cholangitis. AB - We describe the clinical course of a group of patients with primary sclerosing cholangitis who at presentation were diagnosed to have autoimmune hepatitis. The history of one such patient is described in detail. We also compare this atypical sclerosing cholangitis (group I) to typical sclerosing cholangitis (group II) and to autoimmune hepatitis with (group III) and without (group IV) cholestasis. At presentation, mean AST in groups I and III was similar and significantly higher than in group II (P < 0.05). Mean ALP was higher in sclerosing cholangitis than in autoimmune hepatitis but not significantly so. Triaditis was present in all patients in groups I, III, and IV. Piecemeal necrosis and multilobular collapse/fibrosis were equally frequent in groups I, III, and IV. Only the response to corticosteroids helped differentiate among groups. Groups III and IV responded by normalizing AST. In group I, AST improved, but never became normal. As ALP became disproportionately abnormal (ALP-predominant pattern), cholangiography was performed, and the diagnosis of primary sclerosing cholangitis was made in all group I patients. We recommend that cholangiography be performed early in patients with suspected autoimmune hepatitis who partially respond to corticosteroids and develop an ALP-predominant pattern. PMID- 9365128 TI - HCV infection in Egyptian patients with acute hepatitis. AB - The diagnostics of community-acquired acute HCV hepatitis in an endemic area was studied in 110 Egyptian patients with acute jaundice. In the first week of the jaundiced period 30 of 110 patients (27.3%) had anti-HCV antibodies. The majority already showed high levels of anti-HCV IgG (25/30), associated with anti-HCV IgM in nine of them. Five patients showed only an HCV IgM reactivity. Seven had also anti-HEV and/or anti-HBV: their jaundice could then be related to an acute infection caused by those viruses. All patients were infected with genotype 4a, in three associated with the 3a. During the follow-up five patients seroconverted for IgG, while their anti-HCV IgM did not show a uniform pattern of reactivity. Patients with positive serology suspected of an acute HCV infection were older than the patients with other acute hepatitis and showed a lower peak of ALT level. Seroconversion during acute hepatitis strongly indicated HCV as the etiologic agent. However, the detection of anti-HCV IgG antibodies in the jaundiced period showed that the majority of patients had already seroconverted to anti-HCV antibodies; in most of them it is possible to hypothesize a reactivation of a chronic HCV infection. PMID- 9365130 TI - Recovery from diclofenac-induced hypersensitive fulminant hepatitis and prostaglandins. PMID- 9365129 TI - High prevalence of Helicobacter pylori in liver cirrhosis: relationship with clinical and endoscopic features and the risk of peptic ulcer. AB - In 153 consecutive patients with cirrhosis we assessed: (1) the prevalence of IgG to Helicobacter pylori and compared it with that found in 1010 blood donors resident in the same area; and (2) the relationships of IgG to Helicobacter pylori with clinical and endoscopic features and with the risk of peptic ulcer. The IgG to Helicobacter pylori prevalence of cirrhotics was significantly higher than in blood donors (76.5% vs 41.8%; P < 0.0005) and was not associated with sex, cirrhosis etiology, Child class, gammaglobulins and hypertensive gastropathy. In both groups, the prevalence of IgG to Helicobacter pylori was significantly higher in subjects over 40. Among patients with cirrhosis a significantly higher prevalence of Helicobacter pylori was found in patients with previous hospital admission (P = 0.02) and/or upper gastrointestinal endoscopy (P = 0.01) and patients with peptic ulcer (P = 0.0004). Multivariate analysis identified increasing age and male sex as risk factors for a positive Helicobacter pylori serology and no independent risk factors for peptic ulcer. The high prevalence of Helicobacter pylori-positive serology found in the present series is related to age and sex and might also be explained by previous hospital admissions and/or upper gastrointestinal endoscopy. Our results do not confirm the role of Helicobacter pylori as risk factor for peptic ulcer in patients with liver cirrhosis. PMID- 9365131 TI - Diagnosis of HCC. PMID- 9365132 TI - Clinical nutrition in pancreatitis. AB - In patients with acute pancreatitis or an acute flare of chronic pancreatitis, a discrepancy exists between increased protein/calorie requirements induced by a hypermetabolic stress state and reduced ingestion/assimilation of exogenous nutrients, which promotes progressive nutritional deterioration. Patients with severe pancreatitis (defined by > or =3 Ranson criteria, an APACHE II score of > or =10, development of major organ failure, and/or presence of pancreatic necrosis) are more likely to require aggressive nutritional support than patients with mild disease. The type of formula and level of the gastrointestinal tract into which nutrients are infused determine the degree to which pancreatic exocrine secretion is stimulated. Animal studies and early prospective randomized controlled trials in humans suggest that total enteral nutrition via jejunal feeding may be the preferred route to parenteral alimentation in this disease setting. PMID- 9365133 TI - Is biliary lithogenesis affected by length and implantation of cystic duct? Study of 270 patients with endoscopic retrograde cholangiopancreatography. AB - The gallbladder seems to play an important role in lithogenesis. Moreover, the morphology and the implantation of the cystic duct may also influence this process. Our purpose was to evaluate if the length and the implantation of the cystic duct may affect the formation of gallstones. Between April 1992 and March 1994, 270 patients who underwent endoscopic retrograde cholangiopancreatography were included in the study, and the radiological length of the cystic duct was carefully recorded. Patients were divided into two groups: I, absence of lithiasis: 113 patients (65 men, 48 women); and II, gallbladder lithiasis or lithiasis in the common bile duct with or without gallbladder lithiasis: 157 patients (73 men, 84 women). A statistically significant difference was observed among the two groups regarding the insertion of the cystic duct: implantation on the left side of the common bile duct represented a risk factor of lithiasis. The length of the cystic duct was not directly implicated. Hypokinesis of the gallbladder is currently recognized as being a major factor in the initial steps of lithogenesis, but the implantation of the cystic duct can play an important role by increasing cystic duct resistance and causing a reduced washout effect of the gallbladder contents, including cholesterol crystals. PMID- 9365134 TI - Endoscopic stenting for palliation of malignant biliary obstruction and formation of bacterial biofilm resulting in stent clogging. PMID- 9365136 TI - Performance characteristics and comparison of two immunochemical and two guaiac fecal occult blood screening tests for colorectal neoplasia. AB - A new immunochemical test for stool Hb, FlexSure OBT, was compared with the immunochemical HemeSelect and guaiac Hemoccult II and Hemoccult SENSA tests. Blinded development of test cards smeared with stools having added human blood showed better analytical sensitivity of FlexSure OBT (0.2 ml blood/100 g feces), than Hemoccult SENSA (> or =0.5 ml) or Hemoccult II (> or =1.0 ml). All four stool tests were prepared by 403 subjects having endoscopic examinations. The guaiac tests and FlexSure OBT were easy to prepare and develop. The positivity rate of Hemoccult SENSA was 8.7%, Hemoccult II 6%, FlexSure OBT 4.2%, and HemeSelect 3.4%. In this mainly asymptomatic (97%) population, 98% were free of clinically significant neoplasia (five had cancers, three had adenomas > or =1.0 cm). Sensitivity for cancers or adenomas > or =1.0 cm was similar for all tests (62.5-86%, NS) and Hemoccult SENSA had the lowest specificity (92% vs 95-98%, P < 0.05); but both Hemoccult II and Hemoccult SENSA had significantly lower predictive positive values (21% and 14%) than either FlexSure OBT (29%) or HemeSelect (50%) (P < 0.05). If both Hemoccult SENSA and FlexSure OBT were positive in the same subjects (1.7%), sensitivity for cancer or adenomas > or =1.0 cm (50%) was not significantly better than guaiac tests, but specificity (99.2%) and predictive positive (57%) values were improved (P < 0.05). In this population, guaiac tests were as sensitive as immunochemical tests for clinically significant colorectal neoplasia, but with significantly lower predictive positive values. A combination of a sensitive guaiac test (Hemoccult SENSA) and a specific confirmatory test for human Hb (FlexSure OBT) provided high specificity, comparable to HemeSelect. PMID- 9365135 TI - Presence of two signaling TGF-beta receptors in human pancreatic cancer correlates with advanced tumor stage. AB - Transforming growth factor-beta (TGF-beta) signal transduction is mediated via specific cell surface signaling TGF-beta receptors, most notably the type I ALK5 (TbetaR-I[ALK5]) and the type II (TbetaR-II). We evaluated TbetaR-I(ALK5) and TbetaR-II expression in 41 human pancreatic cancer tissue samples and correlated these findings with clinical data of the patients. Northern blot analysis indicated that, in comparison with the normal pancreas, pancreatic adenocarcinomas exhibited 8.0-fold and 4.5-fold increases (P < 0.01), respectively, in mRNA levels encoding TbetaR-I(ALK5) and TbetaR-II. In situ hybridization showed that both TbetaR-I(ALK5) and TbetaR-II mRNA were highly expressed in the majority of pancreatic cancer cells. Immunohistochemical analysis of TbetaR-I(ALK5) and TbetaR-II revealed positive immunostaining in 73% and 56% of the tumors, respectively. Both receptors were concomitantly present in 54% of the pancreatic cancer samples. The presence of TbetaR-I(ALK5) or TbetaR-II and the concomitant presence of TbetaR-I(ALK5) and TbetaR-II in the cancer cells was associated with advanced tumor stage (P < 0.01). These findings show that in many human pancreatic cancers, increased levels of the two signaling TbetaRs are present. The presence of the signaling TbetaRs in advanced tumor stages indicates a role in disease progression. PMID- 9365137 TI - Does perioperative blood transfusion influence long-term prognosis of gastric cancer? AB - We analyzed the influence of packed red blood cell (PRBC) transfusions on the prognosis of 163 patients with gastric adenocarcinoma undergoing subtotal gastrectomy with a curative intention. Over a period of 15 years, our department admitted 505 patients with gastric adenocarcinoma, with curative subtotal gastrectomy being performed in 167 cases. Mean age was 62.2 years (range: 30-87); there was a predominance of males (104 cases; 63.8%). Excluding the four patients who died in the immediate postoperative period (first 30 days), the remaining 163 were reviewed twice yearly in our department until either they died or the study ended. Follow-up averaged 49.5 months, with a median of 36 months. Sixty-nine (42.3%) of the 163 patients received transfusions of PRBC. On correlating the variables with the transfusion, we found a statistical significance only between the rate of transfusion and patient age over 63 years (P < 0.01), with an evolution time of less than three months (P < 0.05) and in tumors of >4 cm (P < 0.05). The five-year survival rate of the nontransfusion patients was 56.9% and of the transfusion patients 40%, with statistically significant differences (P = 0.0132). On studying patients according to tumor stage, we found that blood transfusion had a statistically significant influence on prognosis only in patients with tumor stage III (P = 0.0051). In the univariate analysis of the remaining variables collected, the existence of abdominal tumor (P = 0.0307), tumor size (P = 0.00001), degree of involvement of the gastric wall (P = 0.00001), lymph node involvement (P = 0.00001) and tumor stage (P = 0.00001) revealed a statistically significant influence on prognosis. If we apply Cox's regression model to the variables that in the univariate analysis had a statistically significant influence on prognosis, we found that only tumor size and stage were independent predictors of survival. In our experience, PRBC transfusion does not influence the long-term survival of patients with resected gastric adenocarcinoma. PMID- 9365138 TI - Fine needle trucut biopsy of focal liver lesions: a new technique. AB - A series of 77 ultrasound guided biopsies were performed in 72 patients with an ultrasonographically diagnosed focal liver lesion using a new semiautomated biopsy gun (Temno Biopty Gun) with a 21 G trucut needle. The rate of insufficient sampling was very low (1.5%), and more precise identification of malignant as well as benign lesions was possible when compared with the results of other fine needle techniques available in the literature. No higher complication rate was noted. Our results show a sensitivity of 88%, a specificity of 100%, and an overall accuracy of 91% in identifying malignancy. Therefore we conclude that fine-needle trucut biopsy is a safe and accurate procedure combining the safety of the fine needle with the better sample quality of a large-bore needle biopsy technique. PMID- 9365139 TI - MR cholangiopancreatography (MRCP) in diagnosis of afferent loop syndrome presenting as cholangitis. PMID- 9365140 TI - Gastroparesis and small bowel dysmotility in irritable bowel syndrome. AB - Alterations in both gastric emptying (GE) and small bowel motility have been reported in irritable bowel syndrome (IBS); the relationship, however, between these different measures of upper gut motor function in IBS has not been assessed. The aims of this study were therefore: (1) to compare the prevalence and characteristics of altered small bowel motility in IBS patients with and without delayed GE; and (2) to assess the interrelationships between fasting and postprandial small bowel motility in IBS, accounting for delayed GE. Forty-four IBS patients and 25 healthy controls underwent 24 hr ambulant recording of interdigestive and digestive small bowel motility. On a separate occasion the IBS patients had GE of both solids and liquids measured by a dual-isotope scintigraphic technique. Thirty-nine percent of IBS patients had delayed GE. Patients with normal GE had no interdigestive small bowel abnormalities. However, in patients with delayed GE fasting phase II burst frequency was higher than in controls [median 0.21/hr (IQR 0.15-0.34) vs 0.06/hr (0-0,16), P = 0.004]. Postprandially, abnormal phase III-like activity was higher in diarrhea predominant IBS patients (0-0.08/hr vs 0/hr, P = 0.01), than in patients with normal GE or controls. Furthermore, IBS patients with delayed GE did not have the normal correlation between fasting and postprandial motor parameters (percentage occurrence of clustered contractions, postprandial pattern duration vs preceding MMC cycle length). In conclusion, small bowel motor dysfunction occurs more frequently in IBS patients with concomitant gastroparesis than in patients with normal GE. These findings provide further evidence that a neuropathic process may contribute to the pathogenesis of IBS in a subgroup of IBS patients. PMID- 9365141 TI - Gastric dysrhythmias and delayed gastric emptying in patients with functional dyspepsia. AB - An association between dyspepsia, gastric motility disorders, and myoelectrical abnormalities has been noted. The objective of the present study was to investigate both antral myoelectrical activity and gastric emptying in patients with functional dyspepsia (FD). Electrogastrography (EGG) was performed in 25 adult patients with FD, which had been evaluated by score. After an overnight fast, for 1 hr in the pre- and postprandial state (370 kcal liquid-solid test meal) the following EGG parameters were determined: dominant frequency [DF (cpm)], DF (%) in the normal range (2-4 cpm), bradygastria (<2 cpm), tachygastria (4-10 cpm), dominant frequency instability coefficient (DFIC), and postprandial to fasting power ratio (PR). The data were correlated to results obtained in 20 age- and gender-matched controls. In addition, in 17 consecutive patients the EGG data were compared to the gastric retention of radionuclides after 60 min (liquid solid phase labeled with 99mTc colloid). Patients with FD revealed a preprandial increase in tachygastria compared to controls (P < 0.001). Of 17 FD, seven patients exhibited delayed gastric emptying (t60 retention >68%). These patients showed significantly more pre- and postprandial tachygastrias than patients with normal gastric emptying (P < 0.05). The dyspeptic symptomatology and H. pylori status did not correlate with EGG and radioscintigraphy. Patients with FD frequently reveal impaired gastric emptying and increased tachygastria, which may have pathophysiological significance in some of these patients. PMID- 9365142 TI - Gluten-free diet normalizes mouth-to-cecum transit of a caloric meal in adult patients with celiac disease. AB - The mechanisms responsible for bowel disturbances in celiac disease are still relatively unknown. Recent reports suggested that small bowel motor abnormalities may be involved in this pathological condition; however, there are no studies addressing small bowel transit in celiac disease before and after a gluten-free diet. We studied the mouth-to-cecum transit time of a caloric liquid meal in a homogeneous group of celiac patients presenting with clinical and biochemical evidence of malabsorption and complaining of diarrhea. Sixteen patients were recruited and investigated by means of hydrogen breath test through ingestion of 20 g lactulose together with an enteral gluten-free diet formula. A urinary D xylose test was also done in each patient. Both breath tests and D-xylose tests were carried out basally and after a period of gluten-free diet. Twenty healthy volunteers were recruited as a control group and underwent the same breath testing. At the time of the diagnosis, mouth-to-cecum transit time was significantly prolonged in celiacs with respect to controls (243 +/- 10 vs 117 +/ 6 min, P = 0.0001). The D-xylose test was also abnormal (average urinary concentration 2.8 +/- 0.25 g, normal values >4.5). No correlation was found in patients between mouth-to-cecum transit time and urinary D-xylose output (r = 0.22). After the gluten-free diet period, mouth-to-cecum transit time in celiacs was significantly reduced compared to prediet transit (134 +/- 8 vs 243 +/- 10 min, P = 0.0001) and did not show statistical difference when compared to that found in controls (P = 0.1). The D-xylose test reverted to normal in all but two subjects, who were found to be noncompliant with the diet. Mouth-to-cecum transit time is significantly prolonged in patients affected by untreated celiac disease when compared to healthy controls. This alteration might not be correlated to intestinal malabsorption, and the prolonged orocecal transit could be due to impaired small bowel function (deranged motility?). Since intestinal transit returned to normal values after an adequate gluten-free period, a link with severe active mucosal lesions is suggestive. PMID- 9365143 TI - Nitric oxide synthase (NOS) expression in the myenteric plexus of streptozotocin diabetic rats. AB - Nitric oxide (NO) is an important inhibitory neurotransmitter in the gut. Alterations in NO mediated responses have been described in diabetic animals. The presence of nitric oxide synthase (NOS) reflects the potential for NO synthesis and is found in neurons in the myenteric plexus. The aim of this study was to determine changes in nitric oxide synthase (NOS) expression in the myenteric plexus of the gastrointestinal tract of diabetic rats at three months of streptozotocin-induced diabetes, compared to age matched controls, using immunohistochemistry. Diabetic animals showed a decrease in NOS expression in the antrum, with 59.1 +/- 7.3% of neurons being positive for NOS in diabetes compared to 81.2 +/- 4.7% in controls (P < 0.05). NOS expression in duodenum, ileum, and colon of diabetic animals was not statistically different from controls. Decreased expression of NOS in antrum may contribute to altered gastric emptying observed in diabetics. PMID- 9365145 TI - Uses and cautions for use of polymerase chain reaction for detection of Helicobacter pylori. PMID- 9365144 TI - Metronidazole resistance reduces efficacy of triple therapy and leads to secondary clarithromycin resistance. AB - There has been a significant increase in the prevalence of H. pylori resistance to metronidazole in recent years, while clarithromycin resistance is still relatively rare. In this study we assessed: (1) the effect of primary H. pylori resistance to metronidazole and clarithromycin on the clinical efficacy of a one week regimen consisting of omeprazole, metronidazole, and clarithromycin; and (2) the rate of acquisition of secondary antimicrobial resistance after treatment failure. Eighty-seven patients with duodenal ulceration or nonulcer dyspepsia were included in the study. The primary metronidazole and clarithromycin resistance rates were 35.6% and 3.4%, respectively (all three pretreatment clarithromycin resistant strains had concurrent metronidazole resistance). H. pylori was eradicated in 81.6% of patients. The eradication rate for fully sensitive isolates was 98.2% (55/56) but was significantly reduced to 57.1% (16/28) for isolates that were resistant to metronidazole alone and 0% (0/3) in cases of dual resistance (P < 0.001). Secondary resistance to clarithromycin was acquired in 58.3% of cases of treatment failure. In areas of high prevalence of primary metronidazole resistance, this is a significant cause of treatment failure with this triple therapy regimen. This leads to the selection of strains with dual resistance that are difficult to eradicate and may contribute to an increase in the prevalence of clarithromycin resistance. In such areas an alternative first-line treatment should be prescribed. PMID- 9365146 TI - Density of gastric Helicobacter pylori colonization is not associated with occurrence of dyspeptic symptoms. AB - In most studies, the prevalence of Helicobacter pylori infection in patients with dyspeptic symptoms does not clearly differ from the prevalence in asymptomatic controls. However, the degree of H. pylori colonization might play a role for the occurrence and severity of dyspeptic symptoms. Between August 1993 and July 1994, we screened 1500 apparently healthy volunteers (1036 men, 464 women, 42 +/- 12 years) for H. pylori infection using the [13C] urea breath test. The noninvasive urea breath test enables a semiquantitative assessment of the extent of H. pylori colonization in the stomach. Of the 1500 volunteers, 526 (35.1%) complained of occasional or frequent dyspeptic symptoms. No difference was observed in the H. pylori prevalence between asymptomatic subjects (35.5%) and those with dyspeptic symptoms (35.9%; P > 0.95). A high density of H. pylori colonization in the gastric mucosa was not associated with a higher frequency of dyspepsia (P > 0.80). According to these findings, an eradication therapy on the basis of dyspeptic symptoms alone cannot be recommended as H. pylori is not a proven etiology of dyspepsia. PMID- 9365147 TI - Effect of glyceryl trinitrate on gastric accommodation and symptoms in functional dyspepsia. AB - The purpose of this study was to investigate whether sublingual glyceryl trinitrate influences the size of the proximal stomach and postprandial symptoms in patients with functional dyspepsia. Twenty patients with functional dyspepsia were included in a double-blind, placebo-controlled crossover study with sublingual glyceryl trinitrate. All patients were scanned twice on consecutive days, receiving either placebo or 0.5 mg glyceryl trinitrate randomly 5 min prior to ingestion of 500 ml meat soup. Total symptoms, pain, nausea, and bloating were scored on a visual analog scale before and after the meal. Standardized ultrasonograms were obtained 1, 10, and 20 min postprandially of the proximal and distal stomach. The proximal stomach was larger in the sagittal section at 1 min postcibally (26.5 +/- 3.9 vs 24.8 +/- 4.9 cm2, P = 0.036) and 10 min postprandially (22.0 +/- 5.1 vs 19.8 +/- 5.3 cm2, P = 0.009) after administration of glyceryl trinitrate compared with placebo, whereas a tendency was observed after 20 min (18.7 +/- 5.5 vs 17.3 +/- 5.7 cm2, P = 0.076). The corresponding changes in the frontal diameters were 8.3 +/- 1.1 vs 7.8 +/- 1.2 cm (P = 0.067) after 1 min, 7.2 +/- 0.9 vs 6.4 +/- 0.8 cm (P = 0.001) after 10 min, and 6.3 +/- 1.1 vs 5.6 +/- 1.2 cm (P = 0.016) after 20 min. The area of the distal stomach was not different (P > 0.31) in the two groups. After administration of glyceryl trinitrate, the patients reported less pain (P = 0.048) and nausea (P = 0.023) 5 min postprandially, but this effect was reduced 15 min later. Total symptom score was improved by glyceryl trinitrate treatment (P < 0.042). Sublingual glyceryl trinitrate improves accommodation of the proximal stomach to a meal and reduces postprandial symptoms in a group of patients with functional dyspepsia. PMID- 9365148 TI - Initial and chronic gastric acid inhibition by lansoprazole and omeprazole in relation to meal administration. AB - In a placebo-controlled, double-blind, multiple crossover study, the initial and chronic acid-inhibitory effect of lansoprazole 30 mg, orally administered half an hour before breakfast or immediately after breakfast, and of omeprazole 20 mg, administered postprandially, respectively, was investigated in 16 healthy volunteers, using ambulant 24-hr intragastric pH monitoring. On the first day of medication, only preprandially administered lansoprazole reduced acid secretion significantly (median 24-hr pH 3.0; P < 0.05). On day 15, the median 24-hr intragastric pH of lansoprazole preprandial (pH 4.1), lansoprazole postprandial (pH 4.3), and omeprazole postprandial (pH 3.3), respectively, differed significantly (P < 0.05) from placebo (pH 1.2). It is concluded that the interaction between food intake and lansoprazole administration only is important at the start of oral therapy. Lansoprazole taken before breakfast is effective even on the initial day of treatment. PMID- 9365149 TI - Effects of omeprazole versus placebo in treatment of noncardiac chest pain and gastroesophageal reflux. AB - Gastroesophageal reflux (GER) occurs in 22-66% of patients with noncardiac chest pain (NCCP). Although open-label investigations have shown beneficial effects of antireflux therapy in NCCP, no double-blind, prospective, placebo-controlled studies have been conducted. The purpose of this study was to evaluate the effects of omeprazole compared to placebo in a prospective, double-blind, randomized trial of patients with NCCP and GER. Thirty-six consecutive patients with NCCP and GER documented by 24-hr ambulatory pH testing entered this study. The subjects were randomized to omeprazole, 20 mg by mouth twice a day (17 patients), or placebo (19 patients) for eight weeks. Patients on omeprazole obtained significantly more improvement in the fraction of chest pain days (P = 0.006) and severity (P = 0.032) when compared to placebo. More patients in the omeprazole group reported improvement in individual daily pain scores (81% vs 44%, P = 0.03) and individual severity scores (81% vs 50%, P = 0.057). Thirteen (81%) of the subjects in the treatment arm reported overall symptomatic improvement versus one (6%) in the placebo group (P = 0.001). The results of this study indicate that acid suppression with omeprazole effectively improves chest pain in patients with NCCP and GER. PMID- 9365150 TI - Effects of fluoride on structure and function of canine gastric mucosa. AB - These studies were done to determine the effects of fluoride (F) on the structure and function of the canine gastric mucosa and the possible protective effects of 16,16-dimethyl-prostaglandin E2 (dmPGE2). A portion of the stomach with its vascular supply intact was mounted in a two-compartment chamber, one side of which contained a control solution. Minor effects were caused by exposure to 1 mmol/liter F. Both 5 and 10 mmol/liter F caused marked increases in the fluxes of water and Na, K, and H ions; mucus secretion; and tissue swelling and redness. The extent of these changes did not increase appreciably upon exposure to 50 or 100 mmol/liter F. Histological findings included marked thinning of the surface cell layer, reduced uptake of PAS stain, localized exfoliation and necrosis of surface cells, acute gastritis, and edema. It was concluded that: (1) the threshold F concentration for effects on the structure and function of the gastric mucosa was approximately 1 mmol/liter; (2) the maximum or near-maximum effects were caused by 10 mmol/liter F; (3) the effects persisted for at least 6 hr after the exposure; and (4) dmPGE2 (0.5 microg/ml) did not attenuate the effects induced by F. PMID- 9365151 TI - Mucosal ulcerogenic action of monochloramine in rat stomachs: effects of polaprezinc and sucralfate. AB - Effects of a novel zinc compound polaprezinc [N-(3-aminopropionyl)-L histidinatozinc] and sucralfate on the mucosal ulcerogenic responses induced by monochloramine (NH2Cl) were examined in rat stomachs. Oral administration of NH2Cl (>60 mM) produced severe lesions in unanesthetized rat stomachs, with concomitant increase of lipid peroxidation. These lesions were aggravated by sensory deafferentation but not affected by pretreatment with indomethacin or L NAME. The mucosal ulcerogenic response to NH2Cl was significantly inhibited by oral pretreatment with either dmPGE2 (10 microg/kg), capsaicin (30 mg/kg), or NOR 3 (3 mg/kg), the NO donor. Gastric lesions induced by NH2Cl were also inhibited by prior oral administration of polaprezinc (3-30 mg/kg) as well as sucralfate (30 and 100 mg/kg). The protective effect of polaprezinc was not affected by any pretreatments such as indomethacin, L-NAME, or sensory deafferentation, while that of sucralfate was significantly mitigated in the presence of either indomethacin or L-NAME. On the other hand, mucosal exposure to NH4OH (60 mM) caused a marked PD reduction in ex vivo stomachs made ischemic by bleeding from the carotid artery, followed by severe gastric lesions. These ulcerogenic and PD responses caused by NH4OH plus ischemia were also attenuated by prior application of polaprezinc, while dmPGE2 and sucralfate prevented such lesions without affecting the reduced PD response. These results suggest that: (1) NH2Cl generated either exogenously or endogenously damages the gastric mucosa, (2) both polaprezinc and sucralfate protect the stomach against injury caused by NH2Cl, and (3) the mechanisms underlying the protective action of sucralfate may be partly mediated by both endogenous PGs and NO but may be different from those of polaprezinc. PMID- 9365152 TI - New model of colon interposition following distal gastrectomy in rats. AB - An interposed colon segment has been clinically used as a gastric substitute following an esophagogastric resection for benign or malignant esophageal and gastric cardia disease. The purpose of this study is to establish a rat model of colonic interposition following distal gastrectomy and to investigate its serial mucosal changes. About 80% of the glandular stomach was resected, and a 3-cm segment of the transverse colon interposed isoperistaltically between the remnant stomach and duodenum. Epithelial proliferation and aberrant crypt foci in the interposed colon segment were investigated serially. Crypt lengths in the interposed colon increased significantly (P < 0.05) compared to the remnant colon. The number of goblet cells per crypt per 1 mm in the interposed colon also decreased significantly (P < 0.05) compared to the remnant colon. A PCNA labeling index (LI) of the remnant colon was almost 30%. A PCNA LI in the interposed colon at 4, 8, and 12 months after surgery was 30.8%, 31.8%, and 47.8%, respectively. The PCNA LI in the interposed colon increased significantly (P < 0.05) 12 months after surgery compared to the remnant colon at 4, 8, and 12 months after surgery. Aberrant crypt foci were not detected in the interposed colon segment. In conclusion, we established a rat model of colonic interposition following distal gastrectomy. The interposed colon mucosa adapted well. Long-term mucosal changes of the interposed colon segment should now be studied. PMID- 9365153 TI - One-day high-dose combined therapy of Helicobacter pylori infection. PMID- 9365154 TI - Anti-neutrophil cytoplasmic antibodies in inflammatory bowel disease with special attention for IgA-class antibodies. AB - Perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA) of the IgG class have been reported in inflammatory bowel disease, mainly in ulcerative colitis. Since this disease affects the gastrointestinal tract, we determined whether IgA class ANCA were present in inflammatory bowel disease. We used an indirect immunofluorescence assay for IgG and IgA ANCA testing. Sera from 34 patients with Crohn's disease and 29 patients with ulcerative colitis were collected together with clinical and laboratory data. We found IgA class ANCA of a perinuclear type in 52% of patients with ulcerative colitis and in 9% of Crohn's disease patients. There was a significant association between the presence of IgA ANCA and the occurrence of blood in the feces in the ulcerative colitis group (P = 0.03). IgG ANCA was found in 56% of patients with ulcerative colitis and in 7% of patients with Crohn's disease. Because of partial overlap between IgG and IgA ANCA positivity, the sensitivity of ANCA testing in ulcerative colitis increased from 56% up to 78% by combining IgG and IgA assays. In conclusion, IgA ANCA occurs with a high prevalence in ulcerative colitis. Moreover there is a possible relationship between IgA ANCA and disease activity in ulcerative colitis. PMID- 9365155 TI - Salivary epidermal growth factor plays a role in protection of ileal mucosal integrity. AB - The role of salivary epidermal growth factor (EGF) in the maintenance of ileal mucosal integrity was studied by evaluating the effects of sialoadenectomy on luminal EGF levels, ileal tissue resistance (Rt), and unidirectional flux of [51Cr]EDTA. Mice in groups 1 (SLX) and 2 (SLX + EGF) were subjected to sialoadenectomy, while mice in groups 3 (Sham) and 4 (Sham + EGF) underwent a sham procedure. All animals received normal diet and water, except that EGF (100 ng/ml) was added to water for SLX + EGF and Sham + EGF mice. At seven days after surgery, luminal EGF levels in gastrointestinal segments and ileal Rt were significantly reduced by sialoadenectomy, which was prevented by EGF supplementation. Unidirectional flux of [51Cr]EDTA was 6- to 22-fold greater in the ileum of sialoadenectomized mice, which was prevented by EGF administration. Results suggest that salivary EGF may be the major source of intestinal EGF, and it may play a role in maintenance of ileal mucosal integrity. PMID- 9365156 TI - Insulin-like growth factor 1 in relation to prostate cancer and benign prostatic hyperplasia. AB - Blood samples were collected from 52 incident cases of histologically confirmed prostate cancer, an equal number of cases of benign prostatic hyperplasia (BPH) and an equal number of apparently healthy control subjects. The three groups were matched for age and town of residence in the greater Athens area. Steroid hormones, sex hormone-binding globulin, and insulin-like growth factor 1 (IGF-1) were measured in duplicate by radioimmunoassay in a specialized US centre. Statistical analyses were performed using multiple logistical regression. The results for IGF-1 in relation to prostate cancer and BPH were adjusted for demographic and anthropometric factors, as well as for the other measured hormones. There was no relation between IGF-1 and BPH, but increased values of this hormone were associated with increased risk of prostate cancer; an increment of 60 ng ml(-1) corresponded to an odds ratio of 1.91 with a 95% confidence interval of 1.00-3.73. There was also some evidence for an interaction between high levels of testosterone and IGF-1 in relation to prostate cancer. This finding suggests that, in addition to testosterone, IGF-1 may increase the risk of prostate cancer in humans. PMID- 9365157 TI - Molecular analysis of p21 and p27 genes in human pituitary adenomas. AB - Pituitary tumours develop at a high frequency in p27-knockout mice and retinoblastoma gene-knockout mice, which suggests that cell cycle regulatory genes, such as cyclin-dependent kinase inhibitor genes, are involved in the tumorigenesis of pituitary adenoma. Analysis of p21 and p27 gene abnormalities in human pituitary adenoma was performed in 28 pituitary adenomas by polymerase chain reaction-single-strand conformational polymorphism. No point mutations were detected in these genes. As no abnormalities of the p21 and p27genes were observed, and if these genes are indeed inactivated, it is likely to be via transcriptional or translational defects. PMID- 9365158 TI - Hypermethylation of the WT1 and calcitonin gene promoter regions at chromosome 11p in human colorectal cancer. AB - The short arm of the chromosome 11, known to harbour a number of putative and established tumour-suppressor genes, is frequently hypermethylated in various human neoplasms. We subjected the promoter regions of two genes residing at 11p, namely the tumour-suppressor gene WT1 (Wilms' tumour gene) (11p13) and the calcitonin gene (11p15.5), to methylation analysis in human sporadic colorectal cancer using genomic sequencing. Both genes showed significant hypermethylation of CpG sites within their promoter regions in adenomas and carcinomas compared with normal colonic mucosa. Although the WT1 promoter region was significantly hypermethylated, two CpG sites located in Sp1 motifs were unmethylated in the majority of cases (68-74% of carcinomas). The expression of WT1 gene, as revealed by in situ hybridization, showed no differences between normal colonic mucosa and malignant carcinoma. Together with earlier observations, our present results support the view that the short arm of human chromosome 11 is subjected to widespread regional hypermethylation in various human malignancies. PMID- 9365159 TI - E-cadherin inactivation in lobular carcinoma in situ of the breast: an early event in tumorigenesis. AB - In breast cancer, inactivating point mutations in the E-cadherin gene are frequently found in invasive lobular carcinoma (ILC) but never in invasive ductal carcinoma (IDC). Lobular carcinoma in situ (LCIS) adjacent to ILC has previously been shown to lack E-cadherin expression, but whether LCIS without adjacent invasive carcinoma also lacks E-cadherin expression and whether the gene mutations present in ILC are already present in LCIS is not known. We report here that E-cadherin expression is absent in six cases of LCIS and present in 150 cases of ductal carcinoma in situ (DCIS), both without an adjacent invasive component. Furthermore, using mutation analysis, we could demonstrate the presence of the same truncating mutations and loss of heterozygosity (LOH) of the wild-type E-cadherin in the LCIS component and in the adjacent ILC. Our results indicate that E-cadherin is a very early target gene in lobular breast carcinogenesis and plays a tumour-suppressive role, additional to the previously suggested invasion-suppressive role. PMID- 9365160 TI - Can cancer cells transform normal host cells into malignant cells? AB - A human prostate tumour cell line, LNCaP C4-2, when injected into athymic male nude mice, produced tumours containing: (1) only human cancer cells similar to those injected; (2) only murine stromal cells containing abnormal chromosome constitutions; or (3) both human prostate cancer cells similar to those injected and the transformed murine stromal cells with altered chromosome constitutions. Karyotypic analysis of murine metaphases from all the host-derived tumours showed mostly pseudodiploid chromosome constitutions, with multiple copies (amplification) of mouse chromosome 15 and the absence of a typical Y chromosome. Fluorescence in situ hybridization analysis of these murine cells, using a biotin labelled total human DNA painting probe, further demonstrated the absence of human DNA and the presence of only mouse metaphase and interphase cells in these transformed stromal cells. These results suggest that cancer cells are capable of inducing neoplastic transformation in stromal cells of the host organ by some, as yet unknown, epigenetic mechanism(s). PMID- 9365161 TI - Phosphoglycerate mutase, 2,3-bisphosphoglycerate phosphatase and creatine kinase activity and isoenzymes in human brain tumours. AB - The distribution of phosphoglycerate mutase (EC 5.4.2.1, PGM), 2,3 bisphosphoglycerate phosphatase (EC 3.1.3.13, BPGP) and creatine kinase (EC 2.7.3.2, CK) activity and isoenzymes in various regions of adult human brain and in brain tumours (astrocytomas, anaplastic astrocytomas, glioblastomas and meningiomas) has been determined using electrophoresis. PGM and cytosolic CK exist in mammalian tissues as three isoenzymes that result from the homodimeric and heterodimeric combinations of two subunits [types M (muscle) and B (brain)] coded by separated genes. In addition, a dimeric form and an octameric form of mitochondrial CK exist in mammals. Type BB-PGM was the major PGM isoenzyme found in normal brain, although type MB-PGM and type MM-PGM were also detected. All brain tumours possessed lower PGM activity than normal brain, and meningiomas showed higher BPGP activity. In astrocytic tumours, the proportion of type MB- and type MM-PGM decreased, and in meningiomas these isoenzymes were not detected. Type BB-CK and mitochondrial CK were the only CK isoenzymes detected in normal brain. Astrocytomas possessed lower CK activity than anaplastic astrocytomas and glioblastomas and, in addition, tended to possess lower CK content than normal brain. No qualitative changes of the normal CK isoenzyme pattern were observed in the tumours. PMID- 9365162 TI - Absence of methylation of CpG dinucleotides within the promoter of the breast cancer susceptibility gene BRCA2 in normal tissues and in breast and ovarian cancers. AB - Germline mutations of the BRCA2 gene on chromosome 13q12-q13 predispose to the development of early-onset breast cancer and ovarian cancer. Loss of heterozygosity detected using chromosome 13q markers in the vicinity of BRCA2 is observed in most cancers arising in carriers of germline BRCA2 mutations and also in 30-50% of sporadic breast and ovarian cancers. However, somatic mutations of BRCA2 are extremely rare in sporadic cancers. We have examined the hypothesis that expression of the BRCA2 gene may be suppressed in sporadic breast cancers by a mechanism that is associated with increased methylation of cytosine residues in the promoter region. Using a HpaII/MspI digestion-polymerase chain reaction based assay, the presence of 5-methylcytosine in three CpG dinucleotides within the BRCA2 promoter was assessed in 18 breast or ovarian cancer cell lines, in an SV40 large T antigen immortalized cell line derived from normal breast epithelial cells, in 64 primary sporadic breast cancers and peripheral blood leucocytes from these cases and in a number of other normal human tissues. Methylation was not detected in any of the tissues examined, suggesting that this mechanism of transcriptional repression is unlikely to explain the absence of somatic mutations in sporadic cancers. PMID- 9365163 TI - Enhancement by O6-benzyl-N2-acetylguanosine of N'-[2-chloroethyl]-N-[2 (methylsulphonyl)ethyl]-N'-nitrosourea therapeutic index on nude mice bearing resistant human melanoma. AB - The exposure of cells to O6-benzyl-N2-acetylguanosine (BNAG) and several guanine derivatives is known to reduce the activity of O6-alkylguanine-DNA alkyltransferase (MGMT) and to enhance the sensitivity of Mer+ (methyl enzyme repair positive) tumour cells to chloroethylnitrosoureas (CENUs) in vitro and in vivo. High water solubility and the pharmacokinetic properties of BNAG make it a candidate for simultaneous administration with CENUs by the i.v. route in human clinical use. In vivo we have shown previously that BNAG significantly increases the efficiency of N'-[2-chloroethyl]-N-[2-(methylsulphonyl)ethyl]-N'-nitrosourea (cystemustine) against M4Beu melanoma cells (Mer+) through its cytostatic activity by the i.p. route, but also increases its toxicity. To investigate the toxicity of BNAG and cystemustine when administered simultaneously in mice, we compared the maximum tolerated dose and LD50 doses of cystemustine alone or in combination with 40 mg kg(-1) BNAG by the i.p. route. The toxicity of cystemustine was enhanced by a factor of almost 1.44 when combined with BNAG. To compare the therapeutic index of cystemustine alone and the cystemustine/BNAG combination, pharmacological tests were carried out in nude mice bearing Mer+ M4Beu human melanoma cells. Isotoxic doses were calculated using the 1.44 ratio. The treatments were administered three times by the i.v. route on days 1, 5 and 9 after s.c. inoculation of tumour cells. Although the toxicities of the treatments were equal, BNAG strongly enhanced tumour growth inhibition. These results demonstrate the increase of the therapeutic index of cystemustine by BNAG and justify the use of BNAG to enhance nitrosourea efficiency in vivo by i.v. co injection. PMID- 9365165 TI - 5-Ethynyluracil (GW776): effects on the formation of the toxic catabolites of 5 fluorouracil, fluoroacetate and fluorohydroxypropionic acid in the isolated perfused rat liver model. AB - We studied the effects of 5-ethynyluracil (GW776), a potent inactivator of dihydropyrimidine dehydrogenase, on the metabolism of 5-fluorouracil (5-FU), in particular with respect to formation of the toxic compounds fluoroacetate (FAC) and 2-fluoro-3-hydroxypropionic acid (FHPA), using fluorine-19 nuclear magnetic resonance and the isolated perfused rat liver model. Livers were perfused with 5 FU alone at a dose of 15 mg kg(-1) body weight or with 5-FU + GW776 at doses of 15 mg 5-FU kg(-1) body weight and 0.5 mg GW776 kg(-1) body weight injected 1 h before 5-FU. All 5-FU was metabolized in experiments with 5-FU alone whereas unmetabolized 5-FU represented 94% of the fluorinated compounds measured in experiments with 5-FU + GW776. GW776 modulated both the catabolic and the anabolic pathways of 5-FU, the most striking effect being on the degradative pathway. The amount of 5-FU catabolites decreased by a factor of 27 in the presence of GW776. The modulator led to a decrease in alpha-fluoro-beta-alanine (FBAL) formation by a factor of approximately 110, while fluoride ion formation decreased by a factor of approximately 10. By strongly lowering the metabolism of 5-FU into FBAL, GW776 circumvented the transformation of FBAL into toxic FAC and FHPA. 5-FU anabolites increased by a factor of approximately 7 in the presence of GW776. The level of free fluoronucleotides and 5-fluorouridine-5'-diphosphate sugars was increased up to fivefold. No incorporation of 5-FU into RNA could be measured in experiments with 5-FU alone whereas, although low (0.1% of 5-FU injected dose), it was detectable in experiments with 5-FU + GW776. These results suggest that GW776 may be useful for attenuating the not very common but serious cardiotoxic and/or neurotoxic side-effects of 5-FU that are probably due to FBAL metabolites. PMID- 9365164 TI - B7-1 (CD80) as target for immunotoxin therapy for Hodgkin's disease. AB - In this preclinical study, the potential applicability of an anti-B7-1 immunotoxin (IT) for the treatment of Hodgkin's disease (HD) was investigated. Immunohistochemical analysis demonstrated strong expression of B7-1 on Hodgkin and Reed-Sternberg (R-S) cells and clear expression on dendritic cells, macrophages and some B-cells in tissues, but not on other tissue cells. Flow cytometric analysis demonstrated that B7-1 was expressed on a few monocytes, but not on CD34+ cells from bone marrow, resting T- or B-cells from peripheral blood or epithelial and endothelial cell lines. An anti-B7-1 immunotoxin containing the anti-B7-1 monoclonal antibody (MAb) B7-24 and saporin as toxin moiety was constructed and showed an affinity similar to that shown by the native MAb. It exhibited strong cytotoxicity against the B7-1+ B-cell line Raji (IC50 10(-11) M), R-S cell lines HDLM2, KM/H2 and L428 and also against a B7-1-transfected epithelial cell line, A431, whose parental line lacks expression of B7-1. In clonogenic assays with Raji cells or KM/H2 cells, a 3- or 4-log kill, respectively, was observed. No cytotoxicity was found against the B7-1- epithelial and endothelial cell lines or against haematopoietic progenitor cells. In conclusion, an anti-B7-1 immunotoxin was developed that had good cytotoxicity against R-S cell lines and that may be used in the elimination of R-S cells in vivo. A concomitant elimination of activated antigen-presenting cells may avoid development of antitoxin and anti-mouse Ig responses and allow repeated administration. PMID- 9365166 TI - Enhanced oral bioavailability of paclitaxel in mice treated with the P glycoprotein blocker SDZ PSC 833. AB - Inhibition of intestinal P-glycoprotein might enhance the absorption of orally administered P-glycoprotein substrate drugs. We show here a 10-fold increased oral bioavailability of paclitaxel in mice treated with the P-glycoprotein blocker SDZ PSC 833. These results encourage further research on the development of a clinically useful oral formulation of paclitaxel. PMID- 9365167 TI - The independence of intrinsic radiosensitivity as a prognostic factor for patient response to radiotherapy of carcinoma of the cervix. AB - A study was made of the prognostic value of pretreatment measurements of tumour radiosensitivity (surviving fraction at 2 Gy, SF2) in 128 patients with stage I III carcinomas of the uterine cervix undergoing radiotherapy. The median follow up time was 47 months. In a univariate analysis stratifying patients according to the median value, radiosensitivity was a significant prognostic factor for overall survival, local control and metastasis-free survival. The 5-year survival rate for tumours with SF2 values below the median was 81% and was significantly greater than the rate of 51% for those with SF2 values above the median. In bivariate analyses, SF2 was shown to be independent of disease stage, tumour grade, patient age, colony-forming efficiency and tumour diameter. In a multivariate analysis, radiosensitivity was the most important variable and, after allowing for this, only stage was a significant independent predictor of treatment outcome. These data indicate that, in carcinoma of the cervix treated with radiotherapy, pretreatment tumour intrinsic radiosensitivity is an important prognostic parameter and contributes to prognosis independently of other established and putative parameters. PMID- 9365168 TI - Human testicular germ cell tumours express inhibin subunits, activin receptors and follistatin mRNAs. AB - Germ cell development is influenced by activin and inhibin, which are produced by Sertoli cells. Activin also affects differentiation of mouse embryonal carcinoma cells, which, to a certain extent, resemble the embryonal carcinoma component of germ cell tumours. Therefore, the expression of inhibin/activin subunits, of activin receptors and of the activin-binding protein follistatin was studied in testicular germ cell tumours, using RNAase protection assays. Testicular germ cell tumours of adolescents and adults (TGCTs) and spermatocytic seminomas expressed activin type I and type II receptors (ActRI and ActRII respectively). Seminomas expressed significantly lower levels of ActRIIA (P<0.05, Mann-Whitney U test) and higher levels of ActRIA (P<0.05) and ActRIB (P<0.05) compared with non seminomas. All tumours expressed inhibin beta-subunit transcripts, which are a prerequisite for activin synthesis. Non-seminomas contained significantly higher levels of the inhibin betaA subunit (P<0.001) compared with seminomas. No activin betaC subunit transcripts could be demonstrated by RNAase protection. Inhibin alpha-subunit expression was absent in the spermatocytic seminomas, in six out of nine seminomas and in 10 out of 11 non-seminomas. Follistatin was expressed predominantly in non-seminomas and spermatocytic seminomas. This expression of activin type I and type II receptors in combination with expression of inhibin beta-subunits indicates that activin may act as a para- or autocrine factor in the regulation of growth and differentiation of tumours of human germ cells. PMID- 9365169 TI - Overexpression of hepatic prothymosin alpha, a novel marker for human hepatocellular carcinoma. AB - Identification of gene products exclusively or abundantly expressed in cancer may yield novel tumour markers. We recently isolated a number of cDNA clones, including alpha-prothymosin, from rat hepatocellular carcinoma (HCC) using a subtraction-enhanced display technique. Alpha-Prothymosin is involved in cell proliferation and is regulated by the oncogene c-myc in vitro. In the present study, we analysed alpha-prothymosin gene expression and its correlation with c myc in patients with HCC, cirrhosis and adenoma and in normal controls. Hepatic alpha-prothymosin messenger RNA (mRNA) levels were two- to 9.2-fold higher in tumoral tissues than in adjacent non-tumoral tissues in 14 of 17 patients with HCC, regardless of coexisting cirrhosis and viral hepatitis. No marked difference in alpha-prothymosin mRNA levels was present in patients with adenoma and hepatic cirrhosis and in healthy controls. The c-myc mRNA amounts were two- to fivefold increased in 11 of 17 patients with HCC and correlated significantly with those of alpha-prothymosin (P < 0.001). In situ hybridization revealed that increased alpha-prothymosin mRNA was localized in the tumour nodules of the patients with HCC. These data suggest that overexpression of alpha-prothymosin in HCC patients, correlated with c-myc, is possibly involved in the tumorigenic process and may be a novel molecular marker for human HCC. PMID- 9365171 TI - Family anxiety in advanced cancer: a multicentre prospective study in Ireland. AB - Six home care services in Southern Ireland collected data on a total of 757 patients over a 6-month period. Patient and family well-being were measured using the staff-rated Support Team Assessment Schedule and Karnofsky Index. Five hundred and eight patients died while in care, 75% of whom died at home. At referral, 32% of families were rated as having severe or overwhelming anxiety. During the last week of care, anxiety remained severe for 26% of family members. Patient and family well-being were inter-related, and there were significant interactions between family anxiety and patient physical and psychological symptoms, and communication. Discriminant analysis produced two predictive models. In model 1, family anxiety at referral strongly predicts family anxiety in the last week of life. In model 2, family anxiety at referral is excluded from the analysis, and the significant predictor factors at referral for family anxiety in the last 4 weeks of life are patient symptom control, sex of patient, diagnosis and patient age. PMID- 9365170 TI - Effect of continuous regional vasoactive agent infusion on liver metastasis blood flow. AB - Regionally administered vasopressors might increase tumour chemotherapy uptake by differentially constricting normal and tumour blood vessels, leading to a selective increase in blood flow to the tumour. In this study, we compared the effects of the vasopressors angiotensin II, vasopressin and endothelin I and the vasodilator calcitonin gene-related peptide (CGRP) by continuously measuring liver parenchymal and tumour blood flow during a 30-min regional vasoactive infusion in a rat HSN liver metastasis model. Vasopressin and angiotensin II produced a vasoconstriction that decreased despite continued infusion, while endothelin I infusion led to prolonged vasoconstriction with a more gradual onset. CGRP infusion resulted in increased vessel conductance but a reduction in blood flow due to systemic hypotension. The tumour to normal flow ratio (TNR) was transiently increased during infusion of all pressors, but only endothelin I produced sufficient change to result in a rise in average TNR throughout pressor infusion. Continuous liver and tumour blood flow measurement throughout vasoactive infusion demonstrated that the extent and the duration of blood flow change varied with the agents assessed. No vasoactive agent increased tumour blood flow, but endothelin I had the most suitable vasoactive properties for enhancing tumour uptake of continuously infused chemotherapy. PMID- 9365172 TI - Low levels of basic fibroblast growth factor (bFGF) are associated with a poor prognosis in human breast carcinoma. AB - It has been suggested that angiogenesis and angiogenic factors may be strong predictors of relapse in patients with breast carcinoma. We measured the levels of the angiogenic peptide basic fibroblast growth factor (bFGF) in 140 breast tumour cytosols using an immunoassay. There were no significant differences in bFGF levels between breast non-malignant lesions and primary carcinomas. In 124 cases with primary breast cancer, we observed an association of low bFGF levels (< 400 pg mg[-1]) with increasing tumour size (P = 0.023) and stage of disease (P = 0.002). bFGF levels did not correlate with other variables, including axillary nodes, hormone receptors, cathepsin D and the serum tumour markers CA15.3 and CEA. With a median follow-up of 44.0 months, breast cancer patients with low levels of bFGF had a significantly shorter disease-free survival (DFS) than patients with elevated bFGF (log-rank, P < 0.0001). In a multivariate analysis of DFS, only bFGF, T-stage and histological grade showed statistical significance. In a parallel evaluation of circulating bFGF, we did not observe a correlation between the serum and tissue bFGF levels in the 29 selected cases with matched determinations. Our results indicate that low bFGF levels in breast carcinoma are an independent prognostic indicator of poor prognosis and disease recurrence. PMID- 9365173 TI - Expression of vascular endothelial growth factor (VEGF) in epithelial ovarian neoplasms: correlation with clinicopathology and patient survival, and analysis of serum VEGF levels. AB - Vascular endothelial growth factor (VEGF) is known to be produced by various solid tumours and is thought to be involved in microvascular permeability and/or angiogenesis. To examine the relationship between VEGF expression in ovarian neoplasms and clinicopathological factors or patient survival, expression of VEGF was analysed immunohistochemically in 110 epithelial ovarian tumours. In addition, VEGF levels in the tumour fluid (17 patients), ascites (12 patients) and sera (38 patients) were determined using enzyme immunoassay. Positive immunostaining for VEGF was observed in 97% (68 out of 70) of ovarian carcinomas, which was significantly higher than that of tumours of low malignant potential (LMP) (13 out of 25; 52%) and benign cystadenomas (5 out of 15; 33%) (P < 0.01). In ovarian carcinomas, strong VEGF immunostaining was also observed more frequently in tumours of clear cell type (P < 0.05) in the advanced stage of disease (P < 0.05) and with positive peritoneal cytology (P < 0.01). Patients with strong VEGF staining had poorer survival rates than those with weak or no immunostaining for VEGF (P < 0.01). These findings suggest that strong VEGF expression plays an important role in the tumour progression of ovarian carcinoma. The enzyme immunoassay revealed higher serum VEGF levels in carcinoma patients than those in patients with LMP or benign tumours (P < 0.01). Serum VEGF levels decreased after the successful removal of tumours in ovarian cancer patients and, in one patient, the serum VEGF level was re-elevated during relapse. Therefore, serum VEGF could be used as a marker for monitoring the clinical course of ovarian cancer patients. PMID- 9365174 TI - Breast cancer risk estimation in families with history of breast cancer. AB - Among 288 breast cancer patients (118 with bilateral disease and 165 with diagnosis before 40 years of age), we identified 26 families with a history of breast cancer, including a minimum of three first- or second-degree relatives. Complete pedigrees with verified malignancy data from the Finnish cancer registry were constructed for 22 families. The median age at breast cancer diagnosis of the young probands (< 40 years of age) was 35 years and of bilateral probands was 54 years. The relatives of the young probands were diagnosed with breast cancer at a younger age (median age 54 years) than the relatives of the older (bilateral) probands (median age 60 years). Standard life-table methods were used to compare the risk of breast cancer in the family members with that of the general population. Among the relatives of the young probands, the increased breast cancer risk occurred in the early post-menopausal period, whereas the risk estimate for the relatives of the bilateral probands closely followed that of the general population. In both groups, however, those family members reaching the age of 80 years had a cumulative probability of over 50% of developing breast cancer. The standard life-table method proved useful when assessing the age specific risk for familial breast cancer, taking into account numerous family members as well as their age at disease onset. This kind of analysis can be performed in populations for which reliable cancer registry data are available. It provides a useful tool for selecting individuals for imaging and mutation screening, counselling and experimental chemoprevention programmes. PMID- 9365175 TI - Risk of subsequent primary cancers in patients with carcinoma of the Ampulla of Vater. AB - Data were collected on subsequent primary cancers occurring in 194 individuals diagnosed with ampullary carcinoma during 1979-92 in the north western region of England, UK. Four cancers were identified compared with 6.62 expected (relative risk 0.60), suggesting that individuals with ampullary carcinoma are not at increased risk of developing subsequent primary cancers. PMID- 9365176 TI - Invasive lobular carcinoma of the breast has better short- and long-term survival than invasive ductal carcinoma. AB - The outcome and prognostic factors of 217 women with invasive lobular carcinoma (ILC) and those of 1121 women with invasive ductal carcinoma (IDC) of the breast were compared. The patients were followed up for 10-43 years. Women with ILC had axillary nodal metastases less frequently than those with IDC (43% vs 53%, P = 0.02), although there was no difference in the primary tumour size between the groups. ILCs were more frequently of low grade, had lower mitotic counts and had less tumour necrosis. Furthermore, ILCs had lower S-phase fractions and were more often DNA diploid in flow cytometric analysis than IDCs (P < 0.0001 for all comparisons). The 5- and 30-year corrected survival rates of women with ILC were 78% and 50%, respectively, compared with 63% and 37% for women with IDC (P = 0.001). Small pT1NOMO ILCs (n = 41) had 100% 10-year and 83% 20-year corrected survival rates. In a multivariate analysis, a large primary tumour size, the presence of axillary nodal metastases, a high mitotic count and the presence of tumour necrosis all had an independent prognostic value in ILC. We conclude that ILC is associated with better survival than IDC. PMID- 9365178 TI - Statistical modelling of breast cancer incidence and mortality rates in Scotland. AB - The interpretation of time trends in disease rates can be facilitated using estimable contrasts from age-period-cohort models. Cohort and period trends in breast cancer incidence and mortality rates in Scotland were investigated using contrasts that measure the changes in the linear trends. These contrasts were compared with estimates obtained from mortality rates in the USA and Japan. A significant moderation of both breast cancer incidence and mortality rates was observed in Scotland, associated with cohorts of women born after the Second World War compared with women born between the two world wars. The moderation of breast cancer mortality among cohorts born after 1925 compared with cohorts born before 1925 that was observed in the USA and Japan was also observed in this study. This moderation is not present in the incidence rates. The relative decline in the risk of breast cancer seen in younger cohorts seems to be contradictory to the temporal pattern present among breast cancer risk factors. It may well be that the alteration of eating patterns as a result of rationing in the wartime and immediate post-war period, and the subsequent influence on certain breast cancer risk factors probably produced by such changes, may have had some influence on the development of healthier girls and women. Such speculation could be addressed in a well-designed epidemiological study. There have been no changes in the mortality rate trends with period in Scotland, although the changes in the incidence rate trends with period are consistent with an increase in registration coverage. PMID- 9365177 TI - The risk profile of childhood leukaemia in Greece: a nationwide case-control study. AB - The risk profile of childhood leukaemia in Greece was studied through a case control investigation that included all 153 incident cases of the disease, ascertained throughout the country during 1993 and 1994, and two hospital controls for every case matched for gender, age and place of residence. The data were analysed using conditional logistic regression and the associations are expressed in terms of adjusted odds ratios (OR) and their 95% confidence intervals. Cases were born to mothers of a higher standard education, the OR for an increment of four schooling years being 1.48 (1.17-1.87) and had higher birth weight, the OR for an increment of 500g being 1.36 (1.04-1.77). Pet ownership and birth after a pregnancy with anaemia were associated with increased risk, the ORs being 2.18 (1.14-4.16) and 2.60 (1.39-4.86) respectively. From the frequency analyses, indicative inverse associations were found with birth order, household crowding and previous hospitalization with allergic diseases, whereas indicative positive associations were found with diabetes mellitus during pregnancy and with neonatal jaundice. Substantial or significant elevations were not found with respect to maternal smoking and coffee drinking during pregnancy, diagnostic radiography and ultrasonographic examinations or blood transfusions. A significant inverse association with maternal consumption of alcohol could be due to multiple comparisons, but a detrimental effect can probably be excluded. A non significant positive association with total shots of viral vaccinations and a weak non-significant inverse association with breast feeding were also found. We interpret the findings of this study as being compatible with acute childhood leukaemia being linked with delayed development of herd immunity to fairly common infectious agents, in conjunction with accelerated perinatal and early post-natal growth. PMID- 9365179 TI - Binding characteristics of aromatase inhibitors and phytoestrogens to human aromatase. AB - We have evaluated the binding characteristics of three steroidal inhibitors [4 hydroxyandrostenedione (4-OHA), 7alpha-(4'-amino)phenylthio-1,4-androstadiene 3,17-dione (7alpha-APTADD), and bridge (2,19-methyleneoxy) androstene-3,17-dione (MDL 101,003)], four nonsteroidal inhibitors [aminoglutethimide (AG), CGS 20267, ICI D1033, and vorozole (R83842)], and two flavone phytoestrogens (chrysin, and 7,8-dihydroxyflavone) to aromatase through a combination of computer modeling and inhibitory profile studies on the wild-type and six aromatase mutants (I133Y, P308F, D309A, T310S, I395F, and I474Y). We have generated two aromatase models based on the x-ray structures of cytochrome P450-cam and cytochrome P450bm3, respectively. A major difference between the cytochrome P450cam-based and cytochrome P450bm3-based models is in the predicted lengths of helices F and G. In the cytochrome P450cam-based model, helices F and G lie antiparallel and extend across the active-site face of the molecule from one edge to the center, so that the carboxyl-terminal residues of helix F and the N-terminal residues of helix G make a major contribution to the structure of the active site. In the cytochrome P450bm3-based model, both helices are longer and so extend almost all the way across the active-site face of the molecule. Considering the size of the androgen substrate, we evaluated our results mainly based on the cytochrome P450cam model. The mutations involved in this study are thought to be at or near the proposed active site pocket. The inhibitory profile analysis has produced very interesting results and provided a molecular basis as to how seven aromatase inhibitors with different structures bind to the active site of aromatase. Furthermore, the investigation reveals that phytoestrogens bind to the active site of aromatase in a different orientation from that in the estrogen receptor. PMID- 9365180 TI - Diverse function of aromatase and the N-terminal sequence deleted form. AB - The diverse function of human placental aromatase including estradiol 6alpha hydroxylase and cocaine N-demethylase activity are described, and the mechanism for the simultaneous metabolism of estradiol to 2-hydroxy- and 6alpha hydroxyestradiol at the same active site of aromatase is postulated. Comparison of aromatase activity is also made among the wild type and N-terminal sequence deleted forms of human aromatase which are recombinantly expressed in Escherichia coli. Aromatase cytochrome P450 was reconstituted and incubated with [6alpha,7alpha-(3)H2,4-(14)C]estradiol, 7-ethoxycoumarin, and [N-methyl (3)H3]cocaine. 6Alpha-hydroxy[7alpha-(3)H,4-(14)C]estradiol was isolated as the metabolite of estradiol and the 3H-water release method based on the 6alpha-3H label was established. The initial rate kinetics of the 6alpha-hydroxylation gave Km of 4.3 microM, Vmax of 4.02 nmol min(-1) mg(-1), and turnover rate of 0.27 min(-1). Testosterone competed dose-dependently with the 6alpha-hydroxylation and showed the Ki of 0.15 microM, suggesting that they occupy the same binding site of aromatase. The deethylation of 7-ethoxycoumarin showed Km of 200 microM, Vmax of 12.5 nmol min(-1) mg(-1) and turnover rate of 1.06 min(-1). The N demethylation of cocaine was analysed by the 3H-release method, giving Km of 670 microM, Vmax of 4.76 nmol min(-1) mg(-1), and turnover rate of 0.49 min(-1). All activity was dose-responsively suppressed by anti-aromatase P450 monoclonal antibody MAb3-2C2. The N-terminal 38 amino acid residue deleted form of aromatase P450 was expressed in particularly high yield giving a specific activity of 397 +/- 83 pmol min(-1) mg(-1) (n = 12) of crude membrane-bound particulates with a turnover rate of 2.6 min(-1). PMID- 9365181 TI - The impact of aromatase mechanism on other P450s. AB - Experimental findings from a number of laboratories have converged to show that the conversion of androgens into oestrogen, catalysed by aromatase, involves three distinct reactions which occur at a single active site. That each one of these reactions belongs to a different generic type was revealed by chemical consideration, together with our (18)O-experiments. In particular, these findings highlighted the fact that the third reaction in the sequence occurs by a novel process for which a number of plausible mechanisms have been considered. The scrutiny of these mechanisms has involved either studies on aromatase itself, or on related enzymes which catalyse the aromatase type of cleavage reaction as generalized in equation 1: [equation: see text]. The acyl-carbon cleavage reaction of equation 1 is catalysed by sterol 14alpha-demethylases, accounts for several side-chain fission products formed by CYP17 (17alpha-hydroxylase-17,20 lyase), and constitutes a weak property of certain drug metabolizing P450s, when given aliphatic aldehydes as substrates. From cumulative studies on these enzymes, consensus is beginning to emerge that the acyl-carbon fission may be promoted by the FeIII-OOH intermediate, formed during the catalytic cycles of P450s. The precedent for the direct involvement of the FeIII-OOH species in the reaction of equation 1 is influencing our thinking regarding the mechanism of the conventional hydroxylation reaction. The status of knowledge surrounding the current debate on these issues will be reviewed. PMID- 9365182 TI - Endocrine disorders associated with inappropriately high aromatase expression. AB - Aromatase P450 (P450arom) is responsible for conversion of C19 steroids to estrogens in a number of human tissues, such as the placenta, gonads, adipose tissue, skin and the brain. Aromatase expression in human tissues is regulated by use of alternative promoters in the placenta (promoter I.1), adipose tissue (promoters I.4, I.3 and II) and gonads (promoter II). Aromatase expression is absent in the disease-free adult liver, adrenal and uterine tissues. Excessive or inappropriate aromatase expression in adipose fibroblasts and endometriosis derived stromal cells, as well as in testicular, hepatic, adrenal and uterine tumors, is associated with abnormally high circulating estrogen levels and/or with increased local estrogen concentrations in these tissues. Whether systemically delivered or locally produced, elevated estrogen levels will in turn promote the growth of hormone-responsive tissues. We recently studied aromatase expression in testicular tumor and adipose tissue samples from prepubertal boys with gynecomastia, in hepatocellular cancer and adrenocortical tumor samples from adult men with gynecomastia, in breast adipose tissue samples proximal to breast tumors, and in endometrial cancer, leiomyoma and endometriosis tissues. Excessive aromatase activity and P450arom transcript levels were found in these tissue samples or in cultured cells derived from these tissues. In these neoplastic or non-neoplastic tissues or cells, the regulation of aromatase expression was studied in terms of alternative promoter use, both in vivo and in response to various hormonal stimuli. Our results were suggestive of a common metabolic abnormality associated with activation of a cyclic AMP-dependent signalling pathway that gives rise to transcriptional transactivation of aromatase expression via promoters I.3 and II in all of the above tissues. This article describes the common pathophysiological and molecular features of excessive aromatase expression in these disease states. PMID- 9365183 TI - The role of estrogen in bone growth and maturation during childhood and adolescence. AB - Twenty years ago it was believed that pubertal growth was stimulated by testicular androgen in boys and by adrenal androgen in girls. Estrogen, which was used to inhibit growth in excessively tall girls, was not thought to have growth promoting effects. We hypothesized that estrogen has a biphasic effect on epiphyseal growth, with maximal stimulation at low levels. We showed that the administration of low doses of estrogen, corresponding to a serum estradiol level of about 4 pg/ml (15 pmol/l) caused more than a 60% increase over the prepubertal growth rate in both boys and girls. To test the hypothesis that estrogen is the principal mediator of the pubertal growth spurt in boys, we administered the aromatase inhibitor, testolactone, to boys with familial male-limited precocious puberty. Testolactone produced near normalization of both growth velocity and bone maturation, despite levels of serum testosterone that remained within the adult male range. The observation that low levels of estrogen stimulate growth and bone maturation suggested that estrogen might explain the more rapid epiphyseal maturation of prepubertal girls compared to boys. To determine whether prepubertal girls have higher estrogen levels than prepubertal boys, we developed an ultrasensitive recombinant cell bioassay for estrogen with a sensitivity of 0.02 pg/ml (0.07 pmol/l) estradiol equivalents. Prepubertal girls had approximately eight-fold higher levels of serum estradiol than did prepubertal boys (0.6 +/- 0.6 pg/ml (SD) (2.2 +/- 2.2 pmol/l) vs 0.08 +/- 0.2 pg/ml (0.29 +/- 0.73 pmol/l), P < 0.05). We concluded that the pubertal growth spurt of both sexes is driven primarily by estrogen, and that the more rapid epiphyseal maturation of prepubertal girls (vs boys) may be explained by their higher estradiol levels. PMID- 9365184 TI - ARIMIDEX: a potent and selective aromatase inhibitor for the treatment of advanced breast cancer. AB - Aromatase inhibitors have been available for a number of years and their ability to reduce circulating estradiol levels has been shown to produce clinical benefit in women with advanced breast cancer. Until recently, the only commercially available aromatase inhibitor was aminoglutethimide. Although aminoglutethimide has been shown to be efficacious in the treatment of advanced breast cancer, it does cause significant toxicity and requires the use of concomitant hydrocortisone therapy. Anastrozole is one of a new class of potent aromatase inhibitors able to suppress estradiol to the limit of detection of sensitive assays without suppressing adrenal steroidal synthesis. Two large clinical trials (n = 764) conducted in the U.S.A. and in Europe evaluated two doses of anastrozole, 1 and 10 mg a day, compared to megesterol acetate, 40 mg four times a day, in postmenopausal women who had progressed while on tamoxifen. Response rates and time to progression with anastrozole were similar to those of megesterol acetate. Objective responses (CR + PR) were 10.3%, 8.9% and 7.9% in the 1 and 10 mg of anastrozole and megesterol acetate treatment groups, respectively. Another 25.2%, 22.6% and 26.1% had stable disease for over 24 weeks on 1, 10 mg anastrozole and megesterol acetate, respectively. Anastrozole and megesterol acetate were well tolerated; however, more patients had significant weight gain on megesterol acetate than with anastrozole treatment. The weight gain seen with megesterol acetate continued to increase over time. Anastrozole has a better therapeutic index (fewer side-effects) and has recently been approved by the FDA and a number of other regulatory agencies around the world for the treatment of advanced breast cancer. PMID- 9365185 TI - Exemestane experience in breast cancer treatment. AB - Exemestane is a very potent, orally active, selective and long-lasting steroidal irreversible inhibitor of aromatase. It is 150 times more potent than aminoglutethimide (AG) in inhibiting human placental aromatase (Ki of 4.3 and 671 nM, respectively). The compound is presently under phase III evaluation in Europe and the U.S.A. for the treatment of postmenopausal advanced breast cancer (ABC). Clinical pharmacology studies have been carried out with single doses ranging from 0.5 to 800 mg and repeated doses of up to 600 mg a day, in 132 postmenopausal healthy volunteers and in 185 postmenopausal women with ABC. Results obtained using a very specific and sensitive analytical method (high performance liquid chromatography-radioimmunoassay; HPLC-RIA) indicated that exemestane is extremely effective in inhibiting plasma estrogens levels. Estrogen inhibition is clearly evident at 5 mg a day and maximal suppression for E2, E1 and E1S (>85%, >90% and >90%, respectively) is obtained at 10-25 mg a day. Data from non-controlled phase II studies involving more than 400 patients indicated a clear anti-tumour activity in postmenopausal ABC patients failing multiple hormonal treatments. In 62 patients progressing on AG (> or = 500 mg a day) exemestane treatment resulted in an objective response rate of approximately 24%; disease stabilization > or = 24 weeks was observed in an additional 24% of cases. With regard to safety, although daily doses up to 600 mg were administered, the maximal tolerated dose was not achieved; reported symptoms were mainly related to the pharmacological action of the compound and were usually mild to moderate in severity, resulting in the discontinuation of therapy in less than 3% of cases. In conclusion, the available results suggest that exemestane treatment is associated with minimal toxicity, and may be of significant benefit for ABC women who have exhausted conventional therapy. PMID- 9365186 TI - Effect of estrogen deprivation on the reproductive physiology of male and female primates. AB - The availability of CGS 16949A, CGS 20267 and CGP 47645, a series of aromatase inhibitors (AIs) having high specific activity and specificity, made possible this study wherein the need for estrogen (E) for regulating (a) follicular maturation/ovulation, luteal function and pregnancy establishment, and (b) testicular function of the bonnet monkey (Macaca radiata) has been examined. Generally these compounds, used in the range of 500 microg to 2.5 mg/day did not inhibit follicular maturation although they did reduce E levels. Although low doses had no effect on ovulation it appears that relatively high doses of CGS 20267 and CGP 47645 could be inhibiting it. Three oral doses of letrozole (CGS 20267, each dose of 2 mg) during the follicular phase resulted in the formation of multiple follicles in cycling females, and these could be ovulated by exogenous hCG (1000 IU) treatment. Although administration of AI during the early luteal phase had no effect on progesterone (P) production, it prevented pregnancy establishment. Whereas AI administration in the female had no significant effect on luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels (except at high drug dosages), it significantly increased serum testosterone (T) levels in the male. Sustained high levels of T (30-50 ng/ml) could be maintained for 100 days by administering 2.5 mg of CGP 47465 orally once in 5 days. Blockade of E synthesis in the male led to the disruption of testicular germ cell transformation, which in turn resulted in a significant reduction in sperm production. These studies with aromatase inhibitors in the monkey suggest that these compounds have a potential for use as fertility regulating agents in both the male and female primate. PMID- 9365187 TI - Local estradiol metabolism in osteoblast- and osteoclast-like cells. AB - Bone is an estradiol-responsive tissue. Estrogen withdrawal during the menopause causes loss of bone mass and clinically relevant osteoporosis in a third of all women. Sufficient or impaired local production, as well as degradation of estradiol in cells present in the bone microenvironment might be an important mechanism of rescue or might contribute to the development of osteoporosis, respectively. We therefore investigated aromatase and 17beta-hydroxysteroid dehydrogenase type IV (17beta-HSD IV) expression in osteoblast- and osteoclast like cells. Aromatase mRNA was increasingly expressed in myeloid THP 1 cells differentiated along the monocyte/phagocyte pathway exploiting vitamin D and either granulocyte-macrophage-stimulating factor (GMCSF) or macrophage stimulating factor (MCSF). In long-term cultures, when sequentially exposed to vitamin D (days 0-21) and GMCSF (days 5-10) and plated on collagen, the amount of expression of aromatase mRNA steadily increased along with the increasing expression of osteopontin mRNA, alpha(v) integrin mRNA, c-fms (MCSF-receptor) mRNA and multinucleated cells developing. The conversion of estradiol from testosterone (10(-7) M/l) in the supernatants of dishes mirrored changes in aromatase mRNA expression and by day 21 rose to 30,000 ng/10(7) cells/24 h. 17Beta-HSD IV mRNA expression was abundant in undifferentiated THP 1 cells and was decreased to approximately 50% by day 21. Unstimulated SV-40 immortalized fetal osteoblasts did not express aromatase mRNA, but the expression was stimulated by the addition of the phorbol ester phorbol myristate acetate (PMA). Unstimulated osteoblasts from primary cultures did not express aromatase mRNA. Osteoblast-like osteosarcoma cells MG 63 expressed faint levels of aromatase mRNA in contrast to the osteosarcoma cell line HOS 58. 17Beta-HSD IV mRNA was expressed in fetal osteoblasts as well as in osteoblasts from primary culture, MG 63 and HOS 58 cells. In summary, we can show the expression of estradiol metabolizing enzymes in cells which are present in the bone microenvironment. Impaired aromatase expression and/or enhanced expression of 17beta-HSD IV may contribute to the pathogenesis of osteoporosis. PMID- 9365188 TI - Aberrant expression of aromatase in breast cancer tissues. AB - The expression of aromatase is tissue-specifically regulated through the alternative use of multiple exons 1 and promoters. We analysed expression levels of aromatase mRNA, preferential utilization of multiple exon 1 of the human aromatase gene, and transcriptional regulation of their multiple promoters in breast cancer tissues by newly developed fluorometric methods. The expression levels of aromatase mRNA in breast cancer tissues were significantly higher than those in regions distal to tumours or in non-malignant breast tissues. Aromatase mRNA in these non-malignant tissues was transcribed from skin fibroblast/fetal liver-specific exon 1 (exon 1b) of the aromatase gene. However, in half the cases of breast cancer patients, the utilization of multiple exons 1 in the aromatase mRNA changed from exon 1b to ovary-specific exon 1 (exon 1c) in their breast tissues. Aromatase mRNA in HepG2 cells as well as in non-malignant breast tissues was also transcribed from exon 1b. Then, the promoter region responsible for the exon 1b-specific utilization in HepG2 cells was examined by fluorometric promoter assay using a new reporter containing four major alternative exons 1 and promoters. The results suggested that transcriptional elements determining preferential utilization of exon 1b in the cells was located on the promoter region of exon 1b from -255 to -1145. To investigate further the cause of the elevation of aromatase mRNA and the switching from exon 1b to exon 1c in the transcription of the aromatase gene, the effects of various factors on the expression levels and preference of alternative exons 1 were examined in cultured adipose stromal cells from breast tissues. Aromatase mRNA was transcribed from exon 1b in the stromal cells, cultured in the presence of calf serum. However, removal of the serum or the addition of forskolin or phorbol ester (TPA) induced a rapid elevation of aromatase mRNA and the switching of aromatase transcripts to exon 1c in the cells, whereas TGFbeta almost abolished the expression of aromatase mRNA. Because co-culture of cancer cells such as MCF-7 increased aromatase mRNA of the cells cultured in the serum-containing medium, it is possible that cancer cells secret stimulatory factors acting like forskolin or TPA, or consume serum inhibitory factors acting like TGFbeta, consequently causing levels of aromatase mRNA to increase. PMID- 9365189 TI - Control of aromatase activity in breast tumours: the role of the immune system. AB - Cytokines such as interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF alpha), have been identified as important regulators of aromatase activity in fibroblasts derived from normal and malignant breast tissues, and may play an important role in controlling aromatase activity in breast tumours. The major source of such cytokines within breast tumours remains to be established but macrophages and lymphocytes, which can infiltrate tumours, have been identified as a potential source of aromatase stimulatory cytokines. To obtain further insight into the possible role played by the immune system in cancer development, and in particular its ability to regulate aromatase activity via cytokine production, we have obtained peripheral blood monocytes and lymphocytes from an immunosuppressed kidney transplant recipient, receiving cyclosporin A therapy, and a woman with breast cancer. Monocytes and lymphocytes were stimulated with lipopolysaccharide (LPS), and the conditioned medium (CM) collected from these cells was tested for its ability to stimulate aromatase activity in fibroblasts derived from normal breast tissue from a woman undergoing lumpectomy for the removal of a breast tumour. The white blood cell count was lower for the immunosuppressed patient, mainly because of the reduction in the number of monocytes and lymphocytes. The ability of CM from the monocytes and lymphocytes of the immunosuppressed patient to stimulate aromatase activity was significantly reduced (68% and 82% for monocytes and lymphocytes, respectively) compared with that of CM from the cells of the woman with breast cancer. It is possible, therefore, that immunosuppression, which has been found to be associated with a reduction in the incidence of de novo breast cancer in kidney transplant recipients, may exert its effect by inhibiting cytokine production by the cells of the immune system and thus oestrogen synthesis. In contrast to the stimulatory effects that TNF alpha has on aromatase activity in breast fibroblasts, in MCF-7 breast cancer cells, which possess low aromatase activity, it reduced activity. However, the extent of inhibition of aromatase activity in these epithelial cells was much lower than the marked stimulation which it can induce in breast fibroblasts. PMID- 9365190 TI - Regulation of aromatase activity within the breast. AB - Local oestrogen biosynthesis within the breast can be highly variable, in vitro aromatase activity both in breast cancers and mammary adipose tissue displaying over a 40-fold range between the highest and lowest levels. Evidence is presented to show that: (i) transcriptional activity may influence oestrogen biosynthesis within breast cancers in that both aromatase mRNA and STAT nuclear binding are correlated positively to in vitro aromatase activity; (ii) the local presence of cancer may enhance aromatase activity in particulate fractions and primary fibroblast cultures from mammary adipose tissue; (iii) tumour extracts and breast cyst fluids may induce aromatase in cultured fibroblasts, the active principles responsible for these effects being incompletely defined (although the combination of interleukin (IL)-6 and its soluble receptor dramatically enhances aromatase activity, it is unclear whether this particular cytokine system can account for the stimulatory effects of breast extracts and fluids); (iv) the aromatase activities in both breast cancer and adipose tissues are susceptible to classical aromatase inhibitors such as aminoglutethimide and 4 hydroxyandrostenedione (and to newer inhibitors such as CGS16949 and CGS20267 at low nanomolar concentrations) but reduced sensitivity to 4-hydroxyandrostenedione may be observed in certain breast cancers. These findings may have important implications for the development and progression of hormone-dependent cancers within the breast. PMID- 9365192 TI - Cooperative regulation of the human aromatase cytochrome P450 gene transcription by placenta-specific cis-acting elements. AB - Aromatase cytochrome P450 catalyses the reaction to convert androgens to estrogens by coupling with NADPH-cytochrome P450 reductase in the endoplasmic reticulum. The human aromatase cytochrome P450 gene (CYP19) is expressed in a variety of tissues under regulation of tissue-specific promoters. Previously, we localized a cell-type specific transcriptional enhancer element between -242 and 166 relative to the major cap site of the gene, by transient expression analysis in human BeWo choriocarcinoma cells. In the present study, we demonstrate that the enhancer element consists of two subelements, element I (located between -238 and -200), and element II (located between -196 and -176) as analysed by DNase I footprinting using the nuclear extracts of BeWo cells. The gel mobility shift assay shows that each of these subelements binds specific nuclear factor(s). The transient expression of the bacterial chloramphenicol acetyltransferase gene constructs involving the subelements in BeWo cells reveals that the elements activate reporter gene expression synergistically when present together, nevertheless each of the elements by itself also has an enhancer activity. The transient expression analysis further shows that element I is responsible for the transcriptional synergism with the binding site of a nuclear factor-interleukin-6 (NF-IL-6) (also known as CCAAT enhancer/binding protein beta), which is located between -2141 and -2115 relative to the major cap site of the gene. These results suggest that the enhancer element plays important roles in sustaining the high levels of CYP19 expression in placental cells in cooperation with other cis acting transcritional regulatory elements. PMID- 9365191 TI - Transcriptional regulation of CYP19 gene (aromatase) expression in adipose stromal cells in primary culture. AB - Estrogen biosynthesis in adipose tissue increases with age and obesity, and has been implicated in the development of endometrial cancer and breast cancer. In normal human adipose tissue, expression of the CYP19 gene which encodes aromatase P450, the enzyme responsible for estrogen biosynthesis, is regulated by a distal promoter, namely promoter I.4. Stimulation of expression in adipose stromal cells by members of the type 1 cytokine family, i.e. interleukin (IL)-6, IL-11, leukemia inhibitory factor (LIF) and oncostatin M (OSM), is mediated via a Jak STAT3 signaling pathway and a GAS element upstream of promoter I.4. In contrast, aromatase expression in breast adipose tissue proximal to tumor is increased three- to four-fold to the utilization of another promoter, namely promoter II, proximal to the translation initiation site. In the present report, we show that prostaglandin (PG) E2 is the most potent factor which stimulates aromatase expression via cyclic AMP and promoter II. PGE2 acts via EP1 and EP2 receptor subtypes to stimulate both the PKC and PKA pathways. The combined stimulation of both of these pathways results in the maximal expression of promoter II-specific CYP19 transcripts. Because PGE2 is a major secretory product both of breast tumor epithelial cells and fibroblasts, as well as of macrophages infiltrating the tumor site, then this could be the mechanism whereby estrogen biosynthesis is stimulated in breast sites adjacent to a tumor, leading in turn to increased growth and development of the tumor itself. PMID- 9365193 TI - Quantitative evaluation of human placental aromatase in abnormal pregnancy- anencephalus and hydatidiform mole. AB - To determine why estriol (E3) levels in the urine and serum are extremely low in pregnancies with anencephalus or hydatidiform mole, both the aromatase activity and the tissue P450arom concentration in solubilized fractions of placental or mole microsomes was measured. The aromatase activity was measured by tritiated water assay and the tissue P450arom concentration was determined by sandwich enzyme-linked immunosorbent assay (ELISA). Consequently, any tissue P450arom concentration was at a lower level than the regression line for that in normal placenta. The aromatase activity also showed a tendency to be lower than that in normal placenta. These results therefore suggest that a decrease of E3 in these abnormal pregnancies would result mainly in a lower level of tissue P450arom concentration. PMID- 9365195 TI - Differential regulation of aromatase and androgen receptor in granulosa cells. AB - During follicular development, androgen acts in three distinct ways. During the early stage of follicular differentiation, androgen acts as an enhancer of FSH stimulated follicular differentiation. As follicular differentiation progresses, this effect is decreased and androgen is mainly utilized as a substrate for estrogen synthesis under increasing stimulation of FSH and LH. These two events are mediated by androgen receptor (AR) and aromatase (P450arom), respectively. In the rat and marmoset monkey, AR and P450arom are predominantly expressed in granulosa cells, and both are developmentally regulated. The expression of AR is highest in preantral/early antral follicles and gradually decreases as follicles mature, whereas expression of P450arom is increased as follicular differentiation progresses. We propose that differential regulation of these two androgen utilizing factors contributes to the smooth transition of developing follicles from the early stage of differentiation to the fully mature ovulatory status. A failure of this transition due to improper androgen stimulation might result in follicular atresia. PMID- 9365194 TI - Evidence that functional interactions of CREB and SF-1 mediate hormone regulated expression of the aromatase gene in granulosa cells and constitutive expression in R2C cells. AB - The proximal promoter of the rat aromatase CYP19 gene contains two functional domains that can confer hormone/cAMP inducibility in primary cultures of rat granulosa cells and constitutive expression in R2C Leydig cells. Region A contains a hexameric sequence that binds steroidogenic factor-1 (SF-1). Region B contains a CRE-like sequence that binds CREB and two other factors, X and Y. To determine if CRE binding factors X and Y had overlapping functions with CREB, and to determine if the CREB and SF-1 binding sites exhibited functional interactions in the context of the intact promoter, mutations within the CRE and hexameric SF 1 binding site were generated. Mutations within the CRE showed that CREB but not factors X and Y mediated cAMP-dependent activity of chimeric transgenes in primary granulosa cell cultures. Granulosa cells transfected with constructs that bound CREB but not SF-1 (or the converse) resulted in a loss of approximately 50% cAMP-dependent CAT activity. Transgenes that did not bind CREB or SF-1 exhibited no cAMP-dependent CAT activity. When these same constructs where transfected into R2C Leydig cells, mutation of either the CREB or SF-1 binding sites resulted in a greater than 90% loss of CAT activity. Western blot and immunocytochemistry analyses revealed that the amount of phosphorylated CREB increased in response to hormone/cAMP in granulosa cells and was high in R2C Leydig cells, coinciding with expression of the transgenes and endogenous aromatase mRNA in each cell type. Therefore, in both cell types the aromatase promoter is dependent upon a functional CRE and the presence of phosphoCREB. The CREB and SF-1 binding sites interact in an additive manner to mediate cAMP transactivation in granulosa cells, whereas they interact synergistically to confer high basal transactivation in R2C Leydig cells. Taken together, the results indicated that the molecular mechanisms or pathways that activate CREB, SF-1 or their interaction are different in granulosa cells and R2C cells. PMID- 9365196 TI - Clinical use of aromatase inhibitors in the treatment of advanced breast cancer. AB - The aim of endocrine therapy is to reduce the estrogenic stimulus for tumour growth. After failure of tamoxifen--the standard "first-line" hormonotherapy for advanced breast cancer (ABC)--the most frequently prescribed endocrine therapies are progestins and aromatase inhibitors (AIs) ("second-line" hormonotherapy). Estrogen deprivation through AIs provides effective treatment of hormone dependent ABC in postmenopausal (PMP) women. Over the past few years, the goals of our research programme were to develop more potent, more selective and better tolerated AIs than our first AI, aminoglutethimide (AG). Lentaron (4 hydroxyandrostenedione, formestane), a highly selective steroidal compound was the first of the new AIs to be used in clinical trials. It is a substrate analogue, administered as an i.m. injection every 2 weeks. It is effective in the treatment of ABC with an objective response rate (ORR) similar to tamoxifen and megestrol acetate (MA) and is generally well tolerated; rare instances of injection site reactions have been reported. Afema (fadrozole HCl), a non steroidal AI is active orally, and effectively suppresses estrogen levels in PMP women, but it is not completely selective for aromatase when administered at higher than therapeutic doses. At the therapeutic dose of 1 mg twice a day it has an anti-tumour efficacy similar to MA, a good tolerability and no clinically relevant effects on other hormones of the endocrine system. Letrozole is the fourth of our AIs in clinical development. It is a non-steroidal, achiral, orally active, potent and highly selective competitive AI. Clinical endocrine studies have shown that the dose of 0.5 mg a day is the lowest dose achieving maximum estrogen suppression. Over a wide dose range, a lack of clinically relevant effects on other hormones of the endocrine system has confirmed its high selectivity. In four phase Ib/IIa studies in PMP patients with ABC who failed previous therapy, letrozole produced ORRs of 9, 31, 33 and 36%. One phase IIb/III study has been completed and two others are ongoing, comparing two doses of letrozole with MA or AG to confirm the anti-tumour efficacy of letrozole in the treatment of ABC in PMP women after treatment with anti-estrogens. Preliminary results from the completed trial show that letrozole 2.5 mg is superior to 0.5 mg in terms of ORR, time to progression and time to treatment failure, and is superior to the standard dose of MA in terms of ORR and tolerability. Therefore letrozole 2.5 mg can be recommended as a first choice for the treatment of PMP patients with hormone receptor-positive or unknown ABC after anti-estrogen therapy. PMID- 9365197 TI - Biochemistry and pharmacology of 7alpha-substituted androstenediones as aromatase inhibitors. AB - The inhibition of aromatase, the enzyme responsible for converting androgens to estrogens, is therapeutically useful for the endocrine treatment of hormone dependent breast cancer. Research by our laboratory has focused on developing competitive and irreversible steroidal aromatase inhibitors, with an emphasis on synthesis and biochemistry of 7alpha-substituted androstenediones. Numerous 7alpha-thiosubstituted androst-4-ene-3,17-diones are potent competitive inhibitors, and several 1,4-diene analogs, such as 7alpha-(4'-aminophenylthio) androsta-1,4-diene-3,17-di one (7alpha-APTADD), have demonstrated effective enzyme-activated irreversible inhibition of aromatase in microsomal enzyme assays. One focus of current research is to examine the effectiveness and biochemical pharmacology of 7alpha-APTADD in vivo. In the hormone-dependent 7,12 dimethylbenz(a)anthracene (DMBA)-induced rat mammary carcinoma model system, 7alpha-APTADD at a 50 mg/kg/day dose caused an initial decrease in mean tumor volume during the first week, and tumor volume remained unchanged throughout the remaining 5-week treatment period. This agent lowers serum estradiol levels and inhibits ovarian aromatase activity. A second research area has focused on the synthesis of more metabolically stable inhibitors by replacing the thioether linkage at the 7alpha position with a carbon-carbon linkage. Several 7alpha arylaliphatic androst-4-ene-3,17-diones were synthesized by 1,6-conjugate additions of appropriate organocuprates to a protected androst-4,6-diene or by 1,4-conjugate additions to a seco-A-ring steroid intermediate. These compounds were all potent inhibitors of aromatase with apparent Kis ranging between 13 and 19 nM. Extension of the research on these 7alpha-arylaliphatic androgens includes the introduction of a C1-C2 double bond in the A-ring to provide enzyme-activated irreversible inhibitors. The desired 7alpha-arylaliphatic androsta-1,4-diene-3,17 diones were obtained from their corresponding 7alpha-arylaliphatic androst-4-ene 3,17-diones by oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). These inhibitors demonstrated enzyme-mediated inactivation of aromatase with apparent k(inact)s ranging from 4.4 x 10(-4) to 1.90 x 10(-3) s(-1). The best inactivator of the series was 7alpha-phenpropylandrosta-1,4-diene-3,17-dione, which exhibited a T(1/2) of 6.08 min. Aromatase inhibition was also observed in MCF-7 human mammary carcinoma cell cultures and in JAr human choriocarcinoma cell cultures, exhibiting IC50 values of 64-328 nM. The 7alpha-arylaliphatic androgens thus demonstrate potent inhibition of aromatase in both microsomal incubations and in choriocarcinoma cell lines expressing aromatase enzymatic activity. Additionally, the results from these studies provide further evidence for the presence of a hydrophobic binding pocket existing near the 7alpha-position of the steroid in the active site of aromatase. The size of the 7alpha-substituent influences optimal binding of steroidal inhibitors to the active site and affects the extent of enzyme-mediated inactivation observed with androsta-1,4-diene-3,17 dione analogs. PMID- 9365198 TI - Plasma estrogen suppression with aromatase inhibitors evaluated by a novel, sensitive assay for estrone sulphate. AB - Aromatase inhibition is a well-defined treatment option for postmenopausal breast cancer. Although several aromatase inhibitors such as aminoglutethimide, formestane and fadrozole have been found to inhibit in vivo aromatization by >85%, previous studies reported plasma estrogen levels to be sustained at approximately 20-50% of their control level during treatment with these drugs. The discrepancy could be due to lack of sensitivity or non-specific crossreactions in the radioimmunoassay (RIA) methods. Mean plasma levels of estrone (E1) and estradiol (E2) in postmenopausal women are approximately 80 and 20 pmol/l, respectively; on the contrary, mean plasma levels of the estrogen conjugate estrone sulphate (E1S) are approximately 4-500 pmol/l. Most RIA methods for plasma E2 and E1 measurements have sensitivity limits in the range of 2-3 and 7-10 pmol/l, respectively; accordingly, the suppression of plasma estrogens by more than 80-90% will produce hormone values below the sensitivity limit of the method in many patients. Recently, we developed a new method to determine plasma E1S. This assay has a sensitivity limit of 2.7 pmol/l. In theory, this method may allow the determination of plasma E1S levels suppressed to less than 2% of control values in the majority of patients. Using this method, we found different aromatase inhibitors such as formestane, aminoglutethimide, formestane and aminoglutethimide administered in concert or anastrozole to suppress plasma E1S levels down to 24, 13, 7 and 4%, respectively. The suppression of plasma E1S evaluated with this method thus approaches the percentage aromatase inhibition measured with tracer studies. PMID- 9365199 TI - Future uses for aromatase inhibitors in breast cancer. AB - Over recent years highly potent, well-tolerated aromatase inhibitors have been developed, which essentially obliterate peripheral aromatase activity in postmenopausal women. Their role as the optimal second-line agents (post tamoxifen) for the treatment of advanced breast cancer has recently been established in large comparative clinical trials. Their testing as adjuvant therapy is warranted, but their eventual application in this (or the prophylactic) setting will be dependent on the currently unknown effects of profound oestrogen deprivation on the physiology of postmenopausal women as well as on its efficacy. It is also possible that these new compounds could suppress oestrogen synthesis in premenopausal women, but the consequences on ovarian folliculogenesis might prevent their widespread use in this group of patients. PMID- 9365200 TI - Estrogen production via the aromatase enzyme in breast carcinoma: which cell type is responsible? AB - Studies of breast tumor homogenates from women with breast cancer have demonstrated the synthesis of estrogens in situ through the enzyme aromatase. The present series of investigations sought to determine which cell type within the tumor is responsible for local estrogen biosynthesis, and whether or not the amount produced is biologically important. Accordingly, we utilized an indirect immunohistochemical scoring method (H-score) to determine the relative amount of enzyme present in tumor epithelial and stromal cells. This revealed a value of 13 for tumor stromal cells and 4.8 for the epithelial component. Contributing to this difference is the fact that a greater percentage of cells in the tumor were stromal (45%) than epithelial (37%). To obtain direct evidence that tumor stromal cells could synthesize estrogens, we isolated and grew these cells in tissue culture. Stromal cells originating from within the tumor could be stimulated by known enhancers of transcription to produce nearly as much aromatase as is found in placental microsomes. Stromal cells isolated from benign tissue distal to the tumor exhibited properties similar to those of the tumor stroma. Epithelial cells, in contrast, did not respond to these enhancers and had low levels of aromatase basally. To obtain proof of the principle that local estrogen synthesis can be biologically meaningful, we measured tumor tissue estradiol levels and growth rates in aromatase-transfected MCF-7 cells implanted into nude mice. Local synthesis resulted in tumor levels ranging from 300 to 800 pg/g and growth rates substantially higher than in non-aromatase-containing tumors. These data suggest that tumor stromal cells contribute the major portion of estrogen synthesized in tumors, and that this local synthesis can increase tumor estradiol levels and growth rates. PMID- 9365202 TI - Aromatase in the normal breast and breast cancer. AB - Adipose tissue and muscle constitute the larger proportion of body mass, and therefore aromatization in these tissues is the major source of circulating estrogens in postmenopausal women. Although plasma estrogen concentrations are very low, levels in breast cancers from postmenopausal patients are reported to be 10-fold higher than in plasma and normal tissue. Whereas studies on aromatase activity in the tumor suggest that estrogen may be produced locally, the significance of this contribution has been questioned. Using immunocytochemistry (ICC) to an anti-aromatase antibody, a relatively strong immunoreaction was detected in tumor epithelial cells as well as in the terminal ductal lobular units (TDLUs) of the normal breast. Aromatase expression was detected in the cytoplasm of tumor epithelial cells and the surrounding stromal cells of over 50% of tumors in a series of 19 breast cancers. In situ hybridization (ISH) to aromatase mRNA confirmed the immunocytochemical result that the epithelial cells are the primary site of estrogen synthesis in the breast and breast cancers. In the 10 tumors which showed immunoreaction to aromatase, the average aromatase activity measured in cryosections was 286.5 +/- 18.6 fmol estrogen/mg protein/h (SE), whereas in nine tumors with weak aromatase immunoreaction, the enzyme activity was 154.7 +/- 19.3 fmol estrogen/mg protein/h (P < 0.05) (SE). The functional significance of tumor aromatase and locally produced estrogens on the growth of tumors was suggested by the correlation between aromatase activity and proliferating cell nuclear antigen (PCNA), a marker of cell proliferation (P < 0.005). Although intratumoral aromatase activity did not correlate with steroid receptors significantly, there was a trend for estrogen receptor (ER)-positive tumors to express aromatase. In addition, proliferation ([3H]-thymidine incorporation into DNA) during histoculture, was increased by both estradiol and testosterone in tumors with high aromatase activity. Our results suggest that some tumors synthesize sufficient estrogen to stimulate their proliferation. It may thus be important to inhibit tumor aromatase as well as to reduce circulating levels of estrogen for effective breast cancer treatment. PMID- 9365201 TI - Gene regulation studies of aromatase expression in breast cancer and adipose stromal cells. AB - The expression of aromatase in human breast tumors was studied using the reverse transcription-polymerase chain reaction (RT-PCR) method on 70 breast tissue specimens. An RT-PCR analysis using two oligonucleotide primers derived from exon II of the human aromatase gene revealed that aromatase mRNA was detected in all but three tissue specimens. Furthermore, primer-directed RT-PCR was performed to determine the exon I usage in aromatase mRNA in these breast tumor specimens. The analysis revealed that exons I.3 and PII are the two major exons I present in aromatase mRNA isolated from breast tumors, suggesting that promoters I.3 and II are the major promoters driving aromatase expression in breast cancer and surrounding adipose stromal cells (ASCs). Recently, the regulatory properties of a 696-base pair region that contains promoter II, and is situated immediately upstream of exon II of the human aromatase gene, were investigated. Detailed DNase 1 footprinting analysis, DNA mobility shift assays, and chloramphenicol acetyltransferase (CAT) functional studies of this genomic region were performed and led to the identification of a segment (B1) that could act as a promoter (probably promoter I.3) in adipose stromal and breast cancer cells. The study further revealed that the B1 region could be divided into two domains which were designated RE1 and RE2. RE1 was found to have the promoter activity, and RE2 was found to regulate the promoter activity of RE1, but in different manners in MCF-7 cells (as an example of breast cancer cells) and in ASCs. RE2 was found to function as a positive regulatory element in MCF-7 cells and as a negative regulatory element in ASCs, respectively. It was also found that in several breast cancer cell lines, including MCF-7, the promoter activities of both promoter II and promoter I.3 were found to be suppressed by a negative regulatory element, a silencer, present in the 162 bp fragment which is located upstream from promoter II and downstream from promoter I.3. The precise position of the silencer element (termed S1) was localized by deletion mutation and DNase 1 footprinting analysis, and the silencing activity of S1 on promoter I.3 (in B1 fragment) was confirmed by CAT plasmid transfection experiments. UV crosslinking experiments are being performed to examine the regulatory proteins interacting with the silencer element. These studies serve as the basis for the further characterization of the regulatory mechanism of aromatase expression in human breast cancer and ASCs. PMID- 9365203 TI - Product of aromatase activity in intact LNCaP and MCF-7 human cancer cells. AB - We investigated conversion rates of androgens to estrogens in cultured, hormone responsive prostate (LNCaP) and breast (MCF-7) human cancer cells. For this purpose, we adopted an intact cell analysis, whereby cells were incubated for different incubation times in the presence of close-to-physiological (1 nM) or supraphysiological (1 microM) concentrations of labelled androgen precursors, i.e. testosterone (T) and androstenedione (delta4Ad). The aromatase activity, as measured by estrogen formation, was detected in LNCaP cells (0.5 pmol/ml), even though to a significantly lower extent than in MCF-7 cells (5.4 pmol/ml), using 1 microM T after 72 h incubation. Surprisingly, LNCaP cells displayed a much higher aromatase activity when T was used as a substrate with respect to delta4Ad. In either cell line, T transformation to delta4Ad was relatively low, attaining only 2.8% in LNCaP and 7.5% MCF-7 cells. However, T was mostly converted to conjugates (over 95%), glucuronides and some sulphates, in LNCaP cells, whereas it was only partly converted to sulphates (<10%) in MCF-7 cells. Aromatase activity seems to be inconsistent in LNCaP cells, being strongly affected by culture conditions, especially by fetal calf serum (FCS). Further studies should assess the regulation of aromatase expression by serum or growth factors in different human cancer cells, also using anti-aromatase and/or anti-estrogen compounds, in different culture conditions. PMID- 9365204 TI - Aromatase expression and its localization in human breast cancer. AB - Aromatization or in situ estrogen production by aromatase has been considered to play an important role in the development of human breast carcinoma. In the human breast, aromatase overexpression is observed in the stromal or interstitial cells of the carcinoma, especially at the sites of frank invasion and/or adipose tissue. Transplantation experiments in the nude mouse employing MCF-7 and/or SF TY human fibroblast cell lines revealed that aromatase activity and expression were much higher in the tumour with MCF-7 and SF-TY than that with MCF-7 alone. Aromatase overexpression in human breast carcinoma tissue is considered to occur as a result of carcinoma-stromal cell interactions, i.e. paracrine communication between stromal and carcinoma cells. Aromatase overexpression is correlated with the malignant phenotype in the human breast, but not with stage, age, clinical stages, clinical course, or proliferative activity of breast carcinoma. Aromatase overexpression may be correlated with development, rather than the biological behaviour of breast malignancy. Aromatase overexpression is not necessarily correlated with expression of 17beta-hydroxysteroid dehydrogenase type 1, which converts estrone to estradiol and estrogen receptor. Different mechanisms may be involved in the regulation of expression of these two important estrogen metabolizing enzymes and estrogen receptor in human breast cancer. Aromatase overexpression in intratumoral stromal cells was much more frequently detected in male breast cancer than in female counterparts, which confers a growth advantage on cancer cells in a male hormonal environment with low serum estrogen levels. PMID- 9365205 TI - Autonomous expression of aromatase during development of mouse brain is modulated by neurotransmitters. AB - A transient increase in aromatase activity is known to occur in the hypothalamus of rodents in pre- and postnatal periods. The mechanisms regulating such a developmental increase of brain aromatase was studied in fetal mouse diencephalic cells, by measuring aromatase mRNA levels by a quantitative reverse transcription polymerase chain reaction (RT-PCR) method. When slices of diencephalon were cultured on embryonic day (E) 12, E13 and E15, the level of aromatase mRNA continued to increase for the first 2 to 3 days. A time-dependent increase of mRNA was also shown for 3 days in E13 neuronal cells dissociated with papain and cultured in chemically defined medium. However, no significant increase was observed in E10 or E11 brain cells cultured by either method. Aromatase mRNA was detected in neither cerebral cortex neurons nor astrocytes. An alpha1-selective adrenergic agonist, phenylephrine, increased aromatase in the E13 diencephalic neurons in culture, whereas prazosin, an alpha1-antagonist, suppressed the mRNA level. Ligands for alpha2- or beta-adrenergic receptors did not alter the mRNA level. Substance P, cholecystokinin, neurotensin, and brain natriuretic peptide as well as phorbol 12-myristate 13-acetate and dibutyryl-cyclic GMP all increased the mRNA level. We concluded that: (a) the developmental increase of aromatase mRNA in diencephalic neurons is an autonomous event and is perhaps genetically regulated after E12; (b) aromatase mRNA is expressed in a cell type- and region specific manner; and (c) protein kinases C and G activated via receptors of the specific neurotransmitters may be involved in modulation of the developmental expression of aromatase mRNA. PMID- 9365206 TI - Neuroanatomical distribution of aromatase MRNA in the rat brain: indications of regional regulation. AB - Aromatase, the enzyme responsible for the conversion of testosterone to estradiol, is found in the rat brain and is present in regions of the preoptic area, hypothalamus, and limbic system. Gonadal steroid hormones regulate aromatase activity levels in many brain regions, but not all. Using in situ hybridization, we examined the distribution of aromatase mRNA in the adult male forebrain, as well as the levels of aromatase mRNA in the brains of males and females, and the regulation by gonadal steroid hormones. In the adult male, many heavily labelled cells were found in the encapsulated bed nucleus of the stria terminalis (BNST), the medial preoptic nucleus (MPN), the ventromedial nucleus (VMN), the medial amygdala (mAMY) and the cortical amygdala (CoAMY). The regional distribution of aromatase mRNA was similar in males and females, but males tended to have a greater number of aromatase mRNA-expressing cells in each region compared to females. Aromatase mRNA levels in the BNST, MPN, VMN and mAMY tended to be lower in castrated males than in intact males, whereas aromatase mRNA levels were unaltered by castration in the CoAMY. Further analysis of individual cells expressing aromatase mRNA suggests that aromatase mRNA may be regulated by steroid hormones differentially in specific populations of cells in regions where enzyme activity levels are steroid-hormone-dependent. PMID- 9365207 TI - Sex differences in the regulation of embryonic brain aromatase. AB - Oestrogen formed from androgen by aromatization plays a critical role in the sexual differentiation of the male brain and behaviour. A question which has still to be answered is what regulates the gender-specific changes in aromatase activity forming oestrogen during sensitive periods of brain growth. Using a primary cell culture technique and sexed embryos, we have shown that in the fetal mouse brain, oestrogen formation in the male is neuronal rather than glial and aromatase activity is regionally localized, being higher in the hypothalamus than in the cortex. The aromatase activity measured from cells in culture has the same enzyme binding affinity (apparent Km approximately 40 nM) as intact brain samples. Neurones developing in the embryonic male brain (embryonic day (ED) 15) contain higher aromatase activity (Vmax, 895 fmol/h/mg protein) than the female (Vmax, 604). Although a sex difference exists at early stages of embryonic development (ED 13), the embryonic aromatase system is regulated by steroids later in fetal development. The developing aromatase-containing neuroblasts probably form processes which connect to other aromatase neurones. Immunoreactive staining with an aromatase polyclonal antibody identifies an increase in numbers of aromatase-immunoreactive hypothalamic neuronal cell bodies following testosterone treatment. Testosterone treatment also causes both stimulation of neurite growth and branching as well as functional maturation of aromatase neurones. In particular, there is an increase in aromatase activity per neurone as well as a dramatic increase in the number of neurones expressing the enzyme. Both the functional and morphological changes depend on androgen receptor stimulation for several days in vitro. This conclusion is supported by colocalization studies which reveal a high number of fetal hypothalamic aromatase neurones co-expressing androgen receptor. We conclude that testosterone influences the growth of male hypothalamic neurones containing aromatase at a sensitive period of brain development. Endogenous steroid inhibitors of aromatase, probably formed within the neuroglia, also play a role in the control of oestrogen production. An endogenous 5alpha-reduced metabolite of testosterone, 5alpha-androstanedione, is almost as potent in inhibiting neuronal hypothalamic aromatase activity (Ki = 23 nM) as the synthetic non-steroidal inhibitors such as the imidazole, fadrozole, and the triazoles, arimidex and letrozole. It is clear that the oestrogen-forming capacity of the male hypothalamus has the special characteristics and plasticity of regulation which could affect brain differentiation at specific steroid-sensitive stages in ontogeny. PMID- 9365208 TI - Steroid control and sexual differentiation of brain aromatase. AB - Brain aromatase (ARO) activity in the quail is markedly enhanced by testosterone (T). This effect only becomes detectable after several hours and reaches its maximum within a few days, which suggests enzymatic induction at the genomic level. This idea is reinforced by the fact that T also increases the ARO protein, as observed by immunocytochemistry (ICC) and the ARO mRNA, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR). These changes can be mimicked by the administration of estrogens and therefore presumably require T aromatization. In our first test, injection of the non-steroidal ARO inhibitor, R76713 (racemic vorozole), unexpectedly revealed an increase in ARO immunoreactivity in the preoptic area (POA) of treated birds. This property of R76713 was shared by another non-steroidal inhibitor, fadrozole, but not by two steroidal inhibitors, androstatrienedione (ATD) and 4-hydroxy-androstenedione (OHA). These last two compounds markedly decreased the concentration of brain ARO as estimated by ICC. In parallel, ATD and OHA decreased ARO mRNA concentration measured by RT-PCR but vorozole and fadrozole had no effect on these concentrations in the POA, and only caused them to decrease slightly in the posterior hypothalamus. Together, these data indicate that the removal of estrogens caused by steroidal inhibitors decreases the synthesis of ARO, presumably at the transcriptional level. Additional regulatory mechanisms apparently take place after the injection of non-steroidal inhibitors and probably include increased half-life of the protein. The induction of ARO activity by steroids appears to be greater in males than in females, but this difference has been difficult to localize and confirm by assay methods. We therefore analysed by ICC the tridimensional distribution of ARO-ir neurons in the POA of males and females that were sexually mature or gonadectomized and treated with T-filled or control empty implants. Localized sex differences and effects of T were detected in this way. In particular, males had more ARO-ir cells than females in the lateral POA but a difference in the opposite direction was evident in the medial part of this area. These sex differences are largely activational (i.e. caused by the higher T levels in males) but they may also reflect organizational effects of neonatal steroids. Castration decreased ARO-ir cell numbers in the lateral POA, but increased it in the periventricular region. This anatomically specialized control by T may be mediated by three potential mechanisms that are discussed and comparatively evaluated: a migration of ARO neurons towards the ventricle after castration; a differential colocalization of ARO with estrogen receptors or a differential modulation of ARO neurons by catecholaminergic inputs. PMID- 9365209 TI - Definition of the elements required for the activity of the rat aromatase promoter in steroidogenic cell lines. AB - The rate limiting step in estrogen biosynthesis is catalysed by an enzyme complex that includes the aromatase cytochrome P450 (CYP19), and regulation of the synthesis of this steroidogenic P450 is the level at which estrogen synthesis is controlled. In the rat, initiation of aromatase mRNA transcription occurs immediately 5' to the initiator methionine (proximal promoter) in the rat ovary and in two rat Leydig tumor cell lines that express high levels of aromatase (R2C and H540). Although the same site of transcription initiation is employed in both the Leydig tumor cells and in granulosa cells, the patterns of aromatase expression are distinctive. To define the mechanisms controlling aromatase expression in these model cell lines, we have studied the proximal promoter of the rat aromatase using transfection and gel mobility shift assays. These experiments indicate that the SF-1 motif is required for the expression of the reporter gene in each steroidogenic cell line, and that different combinations of CRE-like elements (particularly those located at -169 and -231) are required for full promoter activity in each steroidogenic cell line. In keeping with the results of the functional assays, we were able to demonstrate the binding of nuclear proteins from each of the Leydig tumor cells to the SF-1 motif in mobility shift assays. Nuclear proteins which bind to the CRE-like elements at 169 and -231 were detected in each of the steroidogenic cell lines, but different complexes were observed using extracts from the Leydig tumor cell lines compared to those visualized using extracts prepared from Y1 cells, an adrenocortical tumor cell line that expresses low levels of aromatase activity. Our findings suggest that, in these model steroidogenic cell lines, differences in the proteins that bind to different combinations of elements within the rat aromatase promoter are responsible for the different patterns and levels of aromatase expression which are observed. PMID- 9365210 TI - Aromatase in axonal processes of early postnatal hypothalamic and limbic areas including the cingulate cortex. AB - It has been shown that sexual dimorphic morphology of certain hypothalamic and limbic areas underlie gender-specific sexual behavior and neuroendocrine mechanisms. The key role played by locally formed estrogen in these developmental events has been revealed during a critical perinatal period. In this study, we aimed to document the presence of estrogen-synthetase (aromatase)-immunoreactive elements in the involved limbic system and hypothalamus of the developing rat brain. On postnatal day 5, animals of both sexes were perfusion-fixed, and sections from the forebrain and hypothalamus were immunolabelled for aromatase using an antiserum that was generated against a 20 amino acid sequence of placental aromatase. Aromatase-immunoreactivity was present in neuronal perikarya and axonal processes in the following limbic structures: the central and medial nuclei of the amygdala, stria terminalis, bed nucleus of the stria terminalis (BNST), lateral septum, medial septum, diagonal band of Broca, lateral habenula and all areas of the limbic (cingulate) cortex. In the hypothalamus, the most robust labelling was observed in the medial preoptic area, periventricular regions, ventromedial and arcuate nuclei. The most striking feature of the immunostaining with this antiserum was its intracellular distribution. In contrast to the heavy perikaryal labelling that can be observed with most of the currently available aromatase antisera, in the present experiments, immunoperoxidase was predominantly localized to axons and axon terminals. All the regions with fiber staining corresponded to the projection fields of neuron populations that have previously been found to express perikaryal aromatase. Our results confirm the presence of aromatase-immunoreactivity in developing limbic and hypothalamic areas. The massive expression of aromatase in axonal processes raises the possibility that estrogen formed locally by aromatase may not only regulate the growth, pathfinding and target recognition of its host neuronal processes, but may also exert paracrine actions on structures in close proximity, including the target cells. PMID- 9365211 TI - Sex differences and androgen-dependent regulation of aromatase (CYP19) mRNA expression in the developing and adult rat brain. AB - Sex differences, androgen dependence and asymmetries of aromatase activity have been reported during ontogeny of the rat. It remains to be elucidated, however, whether the changes in aromatase activity are reflected by similar changes in specific mRNA levels. In addition, very little is known regarding mechanism(s) underlying such differential regulation of aromatase expression. To address these questions, we have employed the in situ hybridization (ISH) technique to examine specific mRNA levels in the brain of both male and female rats at selected stages of development. In prenatal stages of development, at gestational day (GD) 18 and 20, aromatase mRNA was detected in several hypothalamic and limbic brain regions. Semiquantitative analysis of aromatase mRNA did not reveal statistically significant sex differences in any of these regions (except in one experiment at GD20, when a sex difference was found in the medial preoptic nucleus). In contrast, clear sex differences were determined at postnatal day (PN) 2; male animals contained significantly more aromatase mRNA in the bed nucleus of the stria terminalis (BST) and the sexually dimorphic nucleus of the preoptic area (SDN) compared to female rats. Four days later in development, at PN6, sex differences of aromatase mRNA signals were observed in the BST, but were no longer detectable in the SDN. At PN15 and in adult animals, no sex differences could be determined. The effect of flutamide treatment (50 mg/kg/day) was investigated in GD20 fetuses as well as in adult rats. No statistically significant changes in aromatase mRNA expression were found in either case. In summary, our results suggest that differential regulation of aromatase mRNA expression during the critical period of sexual differentiation might, in part, account for the establishment of some of the many sexually dimorphic parameters of the rat brain. The role of androgens in the regulation of the sex-specific and developmental expression of aromatase mRNA in the rat brain remains to be clarified. PMID- 9365212 TI - Sex differences in androgen-regulated expression of cytochrome P450 aromatase in the rat brain. AB - The basis of functional gender differences in adult responsiveness to testosterone (T) is not yet understood. Conversion of T to estradiol by cytochrome P450 aromatase in the medial preoptic area is required for the full expression of male sexual behavior in rats. High levels of aromatase are found in the medial preoptic nucleus (MPN) and in an interconnected group of sexually dimorphic nuclei which mediate masculine sexual behavior. Within this neural circuit, aromatase is regulated by T, acting through an androgen receptor (AR) mediated mechanism. This arrangement constitutes a feedforward system because T is both the regulator and the major substrate of aromatase. Preoptic aromatase is thus more active in adult males than in females because of normal sex differences in circulating androgen levels. However, the mechanism of enzyme induction also appears to be sexually dimorphic because equivalent physiological doses of T stimulate aromatase to a greater extent in males than in females. Dose-response studies indicate that the sex difference is apparent over a range of circulating T concentrations and constitute a gender difference in T efficacy, but not potency. Sex differences in aromatase correlate with sex differences in nuclear AR concentrations in most regions of the sexually dimorphic neural circuit, but not in MPN. These results suggest that males may have larger populations of target cells in which aromatase is regulated by androgen, but the lack of a gender difference in AR levels in the MPN suggests that differences in post receptor mechanisms could also be involved. Measurements of aromatase mRNA in androgen-treated gonadectomized rats demonstrate that sex difference in regulation is exerted pretranslationally. Taken together these results demonstrate a sexually dimorphic mechanism that could potentially limit the action of T in females, and may relate to the enhanced expression of T-stimulated sexual behaviors in males. PMID- 9365213 TI - Molecular aspects of brain aromatase cytochrome P450. AB - Aromatase cytochrome P450 (P450arom) enzyme activity catalyses the conversion of androgens to estrogens in specific brain areas. During central nervous system (CNS) development local estrogen formation influences sexual differentiation of neural structures, regulates neuroendocrine functions and sexual behavior. A proposed mechanism (and re-examination) of the sexual differentiation of the rodent brain is presented. The metabolic pathway of androgen metabolism by P450arom was characterized in the medial basal hypothalamic (MBH) tissue from male rats during various prenatal and postnatal developmental intervals. The P450arom enzyme activity was determined using a saturating concentration of [3H]testosterone as the substrate, and the rates were quantified by scintillation counting. The MBH P450arom activity was highest during prenatal development (i.e. 3-6 pmol/h/mg protein), declined to moderate levels in newborns and infantile animals (approximately 1 pmol/h/mg protein) and then continued to decline to low activity rates in adult animals (approximately 80 fmol/h/mg protein). Regulation of the P450arom gene was characterized by a series of molecular biology studies where the controlling mechanism for brain P450arom was determined in MBH and amygdaloid tissue sites. Evidence for brain P450arom-specific mRNA in perinatal rats is presented as well as comparisons with rat ovary, a rat Leydig tumor cell line (R2C) and human fetal brain P450arom. Specifically, P450arom gene expression is driven in perinatal rat brain tissue by a different promoter compared to rat ovarian tissue or a R2C cell line, whereas human fetal brain tissue utilizes an almost identical promoter segment to that observed in the rodent. These findings provide an insight into the regulation of brain P450arom gene expression and suggest that there is an additional level of control for the expression of this gene during perinatal development. However, further study is necessary to understand the molecular basis of this complex developmental pattern of brain P450arom expression. PMID- 9365214 TI - Structure of aromatase mRNA in the rat brain. AB - In order to elucidate the mechanism of the region-specific expression of rat brain aromatase, we investigated the multiple promoter systems in the brain. Total RNA extracted from the amygdala (AMY) was subjected to a reverse transcription-polymerase chain reaction (RT-PCR) with the primers for mouse brain specific exon I (exon I-f). The nucleotide sequence of the RT-PCR product had 89.4% homology to the corresponding region of exon I-f of the human aromatase cDNA. It was first demonstrated that aromatase mRNA with exon I-f was expressed in the rat brain. This type message was expressed in the hypothalamus-preoptic area (HPOA) but not in the cerebral cortex (CC). Furthermore, total RNAs from the HPOA, AMY and CC of the rat brain were analysed by RT-PCR with the primers for rat ovarian type message-specific exon II. Significant levels of the products were generated in the HPOA and AMY with no signals in the CC. Cortical aromatase mRNA seemed to be unique in that the tissue had no exon I-f and ovarian type mRNAs. We thus analysed the 5'-region of aromatase mRNA in the rat CC by 5'-rapid amplification of cDNA ends (RACE) with antisense primers for exon V. The upstream sequence from the 5'-end of exon IV of the aromatase RACE clones was completely different from that of the aromatase mRNA which encoded the full-translated region. These results indicated that the aromatase gene in the rat brain contained at least three promoters: hypothalamus type (exon I-f), ovarian type and cortical type, and that the region-specific expression of the brain aromatase seemed to be regulated, at least in part, by differential promoter usage. PMID- 9365215 TI - Evolutionary and functional significance of two CYP19 genes differentially expressed in brain and ovary of goldfish. AB - Remarkably high levels of cytochrome P450 aromatase (P450arom) enzyme are expressed in the brains of teleost fish when compared to the ovaries of the same fish, or to the brain or ovaries of other vertebrates. Northern analysis using a full-length P450arom cDNA from a goldfish brain library indicates high accumulated levels of CYP19 mRNA in the brain but fails to detect P450arom mRNA in the ovary. The possibility of different brain and ovarian mRNA variants was investigated. Reverse transcription-polymerase chain reaction (RT-PCR) amplification of ovarian RNA using degenerate primers led to the isolation of a 243 bp P450arom cDNA fragment with approximately 20% of nucleotide and amino acid replacements when compared to the brain cDNA. Southern analysis with sequence specific probes indicated two distinct CYP19 loci, and this was confirmed by PCR restriction enzyme analysis of genomic DNA. Corresponding brain- and ovary-type genomic sequences were identified in a second, diploid fish species (zebrafish), evidence that two genes are not caused per se by tetraploidy in goldfish. RT-PCR analysis of different tissues with sequence-specific primers showed high levels of the brain mRNA variant and much lower levels of the ovarian variant in neural tissues with high enzyme activity. In contrast, the ovary expressed low levels of the ovarian mRNA variant exclusively. The data imply that the expression of two CYP19 genes in goldfish is controlled by distinct regulatory mechanisms. Further studies are required to determine whether the two genes lead to functionally distinct isozymes. PMID- 9365216 TI - Expression of cytochrome P450 aromatase in the channel catfish, Ictalurus punctatus. AB - The cDNA encoding the catfish ovarian aromatase has previously been isolated and described (accession number S75715). As demonstrated previously, the predicted amino acid sequence and enzymatic activity of the encoded protein share a significant degree of similarity to the forms of aromatase found in other vertebrates. Analyses utilizing reverse transcription coupled with the polymerase chain reaction (RT-PCR) demonstrate the expression of aromatase mRNA in catfish brain, testis and ovary. In spite of the evidence provided by Northern blot analysis for a single transcript encoding ovarian aromatase, RT-PCR analysis indicated transcript heterogeneity within the ovary, but not the testis or the brain. Although not characterized, PCR analysis indicated that the transcript complexity of ovarian aromatase was within the encoding region. Until this study, the expression of aromatase and its correlation with the reproductive physiology of fish had not been studied at the molecular level. In the catfish, significant changes in ovarian development were evident following elevation of plasma estradiol titers during October and again in February. Seasonal changes in the expression of ovarian aromatase and 3beta-hydroxysteroid dehydrogenase (3beta HSD) mRNA was reflected in estradiol plasma titers. Ovarian expression of 3beta HSD mRNA commenced a month before the message for aromatase was detected. Both transcripts were present from October to April. As the female approached the time of spawning (in May), the abundance of both aromatase and 3beta-HSD transcripts decreased. The aromatase message was not detected in post-spawning females but 3beta-HSD transcripts were evident. These data indicate that the timely synthesis of estradiol in catfish is caused by the regulation of both 3beta-HSD and aromatase. PMID- 9365218 TI - Porcine aromatases: studies on tissue-specific, functionally distinct isozymes from a single gene? AB - Aromatase cytochrome P450 (P450arom) is expressed in a variety of tissues. Pigs express P450arom as bilaminar blastocysts in utero, and thereafter in the gonads, adrenal glands and placenta. Our studies also demonstrate the existence of porcine isozymes of P450arom which differ substantially in their amino acid composition and function. The placental isoform, most similar to P450arom in other mammals, consists of 503 amino acids. The ovarian isoform, expressed in both theca and granulosa cells, is a 501 amino acid protein exhibiting less than 20% of the activity of the placental isozyme. Furthermore, it is inhibited not only by CGS16949A but also by etomidate which does not inhibit the placental P450arom. Partial sequences generated by the rapid amplification of the cDNA ends (RACE) procedure indicate that the expression of a third isoform in the blastocyst is switched to the placental isozyme during differentiation of the fetal membranes. In addition, these transcripts, and others from the theca, granulosa, testes, adrenal glands and placenta demonstrate differences in the 5' untranslated region (putative exon I) suggestive of tissue-specific alternative splicing. An identical 5'-untranslated sequence was obtained from transcripts expressed in the theca and granulosa. Testes and adrenal transcripts also have identical 5' ends, which differ substantially from the ovarian sequence. Blastocyst and placenta 5'-untranslated sequences differ from each other and from those expressed in the gonads and adrenals. Several tissue-specific transcripts thus encode porcine P450arom. Interestingly, distinct 5' sequences exist for ovarian and testes P450arom mRNAs, suggesting different promoters and therefore regulation in the male and female gonads. The molecular origins of the functional isoforms and the tissue-specific transcripts are uncertain, however partial genomic sequence and other genetic analyses suggest the existence of multiple genes. However, sequence alignment of the placental and ovarian isoforms indicates complete conservation of putative exon III, so that complex splicing remains a possibility. Clearly, the regulation of P450arom expression is more complex in the pig than in other vertebrates investigated to date. PMID- 9365217 TI - Regulation of aromatase expression in the ovary and placenta: a comparison between two species. AB - The conversion of C19 steroids to estrogens is catalysed by aromatase P450 (P450arom; product of the CYP19 gene). Tissue sites of expression include the gonads and brain; however, in a small subset of mammals, P450arom is also expressed in the placenta. In humans, gonadal expression employs a promoter proximal to the start site of translation, whereas expression in the placenta relies on a promoter which is distal to this site. We characterized the bovine CYP19 gene in both the ovary (OV) and placenta (PL), to determine if this method of regulation of tissue-specific expression is employed in other species. Both bovine and human species express P450arom in these tissues, however, the pattern of expression is very different. In both humans and cattle, P450arom is expressed in the granulosa cells of the ovary, however, after ovulation only the luteinized granulosa cells of the human continue to express P450arom. There is a high degree of sequence identity (>70%) shared between humans and cattle in the OV-specific 5'-flanking DNA, whereas little identity (<40%) was found between humans and cattle in the PL-specific DNA. Promoters and 5'-flanking regions of human and bovine CYP19 genes were subcloned into a luciferase (LUC) vector. Bovine PL specific constructs transfected into JEG-3 human choriocarcinoma cells failed to express LUC activity. When OV-specific constructs were transfected into luteinized bovine granulosa cells, there was no change in LUC activity in cells transfected with the bovine constructs after treatment with forskolin, whereas all of the corresponding human constructs expressed LUC activity. The bovine 5' flanking DNA lacks a cAMP-responsive element-like sequence (CLS) critical for cAMP-stimulated transcription of P450arom in the human ovary. With the absence of this CLS sequence in the bovine gene, there appears to be little enhancement of transcription by cAMP in the portion of the 5'-flanking region studied so far. When the analogous region of the bovine promoter was mutated to the human CLS, only a partial restoration of LUC activity was observed. An additional element therefore appears to be important in preventing the full expression of the bovine CYP19 gene in luteinized granulosa cells. PMID- 9365219 TI - Temperature-dependent aromatase expression in developing diamondback terrapin (Malaclemys terrapin) embryos. AB - In the diamondback terrapin, Malaclemys terrapin, males hatch at incubation temperatures below 28 degrees C whereas females hatch at temperatures above 30 degrees C. When estrogen is applied to the eggs at male temperatures early in development, females are produced. These data suggest that the enzyme necessary for estrogen synthesis (CYP19, aromatase) in the developing gonad plays a critical role in sex determination in these vertebrates. Accordingly, we have begun an examination of the role and regulation of the aromatase gene in sex determination in the diamond back terrapin, Malaclemys terrapin. We have obtained full-length cDNAs for terrapin ovarian aromatase. Using reverse transcription polymerase chain reaction (RT-PCR) on mRNA from various tissues we have determined that aromatase is expressed in the female brain and ovary, whereas it is only expressed in the brain of the male. Brain expression of aromatase occurs before stage 15, the beginning of the temperature-dependent sex determining period. Ovarian expression occurs sometime later. To quantify expression levels, we have developed a competitive RT-PCR technique to study the ontogeny of aromatase transcript levels throughout development. The sensitivity of our assay (0.001-10 atmol of transcript) permits us to analyse individual embryonic adrenal/kidney/gonadal complexes without pooling samples. Female hatchlings (stage 26) brains express higher aromatase mRNA levels than male brains (381 +/- 80 vs 202 +/- 85 atmol/microg RNA, respectively). Similarly, ovaries express significantly higher aromatase mRNA levels than hatchling testes (352 +/- 117 vs <0.001 atmol/microg RNA, respectively). PMID- 9365220 TI - Subtypes of the muscarinic receptor in smooth muscle. AB - Muscarinic receptors are expressed in smooth muscle throughout the body. In most instances, the muscarinic receptor population in smooth muscle is composed of mainly the M2 and M3 subtypes in an 80% to 20% mixture. The M3 subtype mediates phosphoinositide hydrolysis and calcium mobilization, whereas the M2 subtype mediates an inhibition of cAMP accumulation. In addition, a variety of ionic conductances are elicited by muscarinic receptors. Muscarinic agonists stimulate a nonselective cation conductance that is pertussis toxin-sensitive and dependent on calcium. The pertussis toxin-sensitivity of this response suggests that it is mediated by M2 receptors. Following agonist induced depolarization of smooth muscle, voltage dependent calcium channels are activated to enable an influx of calcium. In some instances, muscarinic agonists enhance this conductance through a mechanism involving protein kinase C, whereas in other instances, muscarinic agonists suppress this calcium conductance. Smooth muscle often contains calcium activated potassium channels that tend to repolarize the membrane following calcium influx. Activation of muscarinic receptors suppresses this potassium conductance in some smooth muscles. Under standard conditions, muscarinic agonists elicit pertussis toxin-insensitive contractions through activation of the M3 receptor. When most of the M3 receptors are inactivated, it is possible to measure a pertussis toxin-sensitive contractile response to muscarinic agonists that is most likely mediated through M2 receptors. M2 receptors also cause an indirect contraction by inhibiting the relaxant effects of agents that increase cAMP (e.g., forskolin and isoproterenol). PMID- 9365221 TI - S15261, a novel agent for the treatment of insulin resistance. Studies on Psammomys obesus. AB - S15261 is a novel compound that has been proposed for the treatment of insulin resistance syndrome. We have studied the effects of this drug in insulin resistant sand rats (Psammomys obesus). When sand rats are transferred from their natural desert environment and placed on a laboratory chow diet, they become overweight, develop hypertriglyceridaemia, hypercholesterolaemia, become insulin resistant, and ultimately diabetic. In the present study glucose intolerant animals, with very mild if any hyperglycaemia were used. Chronic treatment for a month with S15261 normalised plasma levels of triglycerides and cholesterol. The effects on cholesterol were the result of a decrease in LDL- and VLDL-cholesterol without any modification of HDL-cholesterol. In this study only female sand rats showed elevated plasma glucose levels, which were normalised by S15261. The compound also decreased plasma insulin levels both in male and female sand rats. An oral glucose tolerance test showed a major improvement in glucose tolerance in both male and female animals treated with S15261. These data confirm in another animal model the therapeutic benefits of S15261 in insulin resistant states. PMID- 9365222 TI - Inhibition of bacteriocolonic pathway for ethanol oxidation by ciprofloxacin in rats. AB - Many colonic bacteria possess marked alcohol dehydrogenase (ADH) activity and are capable of oxidizing ethanol to acetaldehyde both in vitro and in vivo. We have recently shown that part of ingested ethanol is metabolized to acetaldehyde in the colon during normal alcohol metabolism. To assess the contribution of this bacteriocolonic pathway for ethanol oxidation to total ethanol metabolism, the elimination rate of ethanol, faecal aerobic flora and faecal ADH activity were determined in rats before and after the treatment with ciprofloxacin (200 mg/kg/day) for four days. Ciprofloxacin treatment decreased ethanol elimination rate from 310+/-9 to 282+/-13 mg/kg/h (mean+/-SE; p<0.02), markedly reduced faecal aerobic flora, and also lowered faecal ADH activity from 63+/-17 to 17+/-7 nmol/min/mg faeces (p<0.05). Neither hepatic ADH nor microsomal ethanol oxidizing system activities were affected by the ciprofloxacin treatment. On the contrary, an acute intraperitoneal dose of ciprofloxacin had no effect on the rate of ethanol elimination. These results support the significant role of the bacteriocolonic pathway in total ethanol elimination, and open a new, microbiological, perspective for studies on ethanol metabolism and pathogenesis of alcohol related organ damages. PMID- 9365223 TI - Hypoxia-induced differential electrophysiological changes in rat locus coeruleus neurons. AB - The effects of hypoxia on rat locus coeruleus (LC) neurons were investigated by intracellular recording from in vitro brain slices. In response to a brief exposure to hypoxic medium (2-5 min), equilibrated with 95% N2 - 5% CO2, two populations of cells could be distinguished, type 1 neurons (61%), showing hyperpolarization (9.3 +/- 0.4 mV, n = 125) and cessation of spontaneous action potentials, and type 2 neurons (39%), displaying gradual pure depolarization (6.0 +/- 0.3 mV, n = 80), instead of hypoxic hyperpolarization. Both types of response were associated with a reduction in membrane input resistance (34 +/- 1% for type 1 cells, n = 125, and 21 +/- 2% for type 2 cells, n = 68). While both types of neurons share similar electrophysiological properties, their membrane input resistance differ significantly (type 1 cells: 144 +/- 5 M omega, n = 125; type 2 cells: 183 +/- 9 M omega, n = 80, p < 0.001). These responses were compared to cyanide-induced chemical hypoxia. Cyanide (2 mM) induced the identical membrane response as effected by nitrogen hypoxia. All cells which responded to nitrogen saturated hypoxic medium with a pure depolarizing response gave a similar response to cyanide and all neurons hyperpolarized by cyanide were also hyperpolarized by hypoxic medium. Moreover, the K(ATP) channel opener, diazoxide (1 mM), could mimic the hypoxia-induced hyperpolarization in type 1 neurons (10.6 +/- 0.9 mV, n = 18), but was unable to induce hyperpolarization in type 2 cells (n = 13). In addition, the N2-hypoxia-induced hyperpolarization was completely blocked by tolbutamide (200 microM, n = 8) or glibenclamide (3 microM, n = 9). These results indicate that a brief period of hypoxia evokes two different responses in LC neurons and this may be due to the heterogeneous distribution of K(ATP) channels among different LC neurons. PMID- 9365224 TI - Inhibitory effect of agmatine on naloxone-precipitated abstinence syndrome in morphine dependent rats. AB - Effects of agmatine, which is an endogenous polyamine metabolite formed by decarboxylation of L-arginine, were investigated on the morphine abstinence syndrome in rats. Two pellets containing 75 mg morphine base (total 150 mg) were implanted subcutaneously on the back of rats. Seventy-two hours after morphine implantation, agmatine sulphate (20, 30 and 40 mg/kg) or saline was injected intraperitoneally. Forty-five min later, naloxone (2 mg/kg) was injected intraperitoneally to induce precipitated withdrawal. Immediately after naloxone injection, rats were observed for 15 min, and abstinence syndrome signs, which included jumping, wet dog shake, writhing, defecation, ptosis, teeth chattering and diarrhea were counted or rated. Agmatine attenuated all of the signs of the morphine abstinence syndrome dose dependently and significantly. Our results suggest that agmatine prevents naloxone-precipitated abstinence syndrome in morphine dependent rats; thus, this drug may be beneficial in the treatment of opioid dependence. PMID- 9365225 TI - Deprenyl stimulates the release of luteinizing hormone from the pituitary in vitro. AB - The direct effects of deprenyl on the pituitary were investigated by measuring the release of luteinizing hormone (LH) from the pituitary glands of male Sprague Dawley rats in vitro. Basal release of LH was determined by incubating the pituitaries in Krebs-Ringer Henseleit (KRH) solution with 0, 0.1, 1, or 10 mM of deprenyl for 1 h. In the control group, LH release was not different in pre- and posttreatment periods. In contrast, in the 10 mM group, LH release increased by 436% (p<0.01). Incubation of pituitaries with 0.1 or 1 mM deprenyl did not alter LH release. It is concluded that deprenyl a monoamine oxidase inhibitor, can also act directly on the pituitary. PMID- 9365226 TI - The lack of effects of nonthermal RF electromagnetic fields on the development of rat embryos grown in culture. AB - Rat embryos (9.5 days old) were exposed for up to 36 h to various radio frequency (RF) electric and magnetic fields (modulation frequency: 16, 60, 120 Hz; electric field strength: 60, 600 V/m; magnetic induction: 0.2, 2.0 microT). A resonator technique was used to generate standing waves thus fulfilling three conditions: The site of maximum electric and magnetic oscillations could be separated, the field strengths were known exactly and a high homogeneity over the sample volume was achieved. In each frequency region the transmitter power levels were set to give specific absorption rate (SAR) values spreading from far below to far above the values met in the field of telecommunication (0.2, 1.0 and 5.0 W/kg). The criteria used to examine the embryos on day 11.5 for possible structural effects consisted of a scoring system, photographs, histology using both light and electron microscopy and determination of the protein content. All these data have been taken as sets of different intermediate frequency (IF) amplitude modulation of the RF carriers. Neither the electric nor the magnetic fields tested interfered significantly with the normal growth and differentiation of the embryos in vitro. PMID- 9365227 TI - N-arachidonylethanolamine (anandamide) formation from N arachidonylphosphatidylethanolamine in rat brain membranes. AB - Labeled L-N-arachidonylphosphatidylethanolamine (L-N-arachidonyl PE), a likely precursor of N-arachidonylethanolamine (anandamide), as well as its D-isomer, were synthesized using [14C]arachidonic acid. Anandamide was formed by incubating L-N-arachidonyl PE and rat brain membrane with phenylmethylsulfonyl fluoride (PMSF), an inhibitor of anandamide amidohydrolase. Formation of anandamide from L N-arachidonyl PE was inhibited by p-chloromercuriphenylsulfonic acid (p-CMPS), sulfhydryl reagent, and heat inactivate pre-treatment. D-N-Arachidonyl PE, an unnatural analog for N-arachidonyl PE, did not form anandamide. PMID- 9365228 TI - Studies on vasorelaxation by tetrapentylammonium ions in rat aortic rings. AB - Tetrapentylammonium ions (TPA+) relaxed the isolated rat aortic rings precontracted with phenylephrine and high extracellular K+ in a concentration dependent manner with respective IC50 values of 38.9 +/- 3.9 microM and 40.2 +/- 2.9 microM. Other quaternary ammonium ions with a carbon side chain of varying length did not induce relaxation. The relaxant effect of TPA+ was independent of the presence of the endothelium, and was unaffected by various putative blockers of K+ channels such as iberiotoxin (100 nM), glibenclamide (3 microM) and 4 aminopyridine (1 mM). In addition, tetrodotoxin (3 microM), indomethacin (10 microM) and methylene blue (10 microM) had no effect on the TPA+-induced relaxation. TPA+ (50 microM) and procaine (10 mM) completely abolished the phasic contractile response to caffeine in Ca2+-free solution. In the absence of extracellular Ca2+, phorbol 12,13-diacetate (PDA) evoked a sustained tension and TPA+ concentration-dependently reduced the contraction with IC50 of 30.7 +/- 3.1 microM. TPA+ reduced the sustained tension of the similar magnitude induced by phenylephrine, 60 mM K+ and active phorbol ester with similar potencies. These results indicate that TPA+ could act as a non-selective relaxant in arterial smooth muscle. This vasorelaxant effect is unique for TPA+ since other quaternary ammonium ions did not show the similar action in the rat aorta. PMID- 9365229 TI - Serotonin 5HT2A receptor activation inhibits inducible nitric oxide synthase activity in C6 glioma cells. AB - C6-glioma cells endogenously express both 5HT2A receptors and inducible nitric oxide synthase (iNOS). iNOS can be induced by transcriptional activation to produce nitric oxide (NO) in response to a challenge with lipopolysaccharide (LPS). Experiments were conducted to determine whether 5HT2A receptor activation could modify the production of NO in response to LPS. Incubation of 10 microg/ml LPS with C6-glioma cells for a period of 24 hours resulted in a 2.6 fold increase in nitrite levels, as a measure of NO levels, over vehicle treated controls. Co incubation with the selective 5HT2A receptor partial agonist (+/-)-2,5-dimethoxy 4-iodoamphetamine (DOI) produced a dose-dependent inhibition of the LPS-induced nitrite levels of 22% with an IC50 of 16 nM. The full agonists serotonin (5HT) and alpha-methyl-5HT produced an inhibition of approximately 30% at a concentration of 1 microM. The inhibitory effect of 1 microM DOI was blocked by the 5HT2A receptor antagonists spiperone and ritanserin (10 nM). Inhibition of protein kinase C (PKC) using 100 nM chelerythrine prevented the DOI-mediated decrease in LPS-induced nitrite levels. Addition of DOI to the cells after 1 hr following the LPS addition did not produce a decrease in nitrite levels indicating iNOS was not modified post-translationally. The data demonstrate that iNOS activity can be modulated by serotonin 5HT2A receptor activation, most likely at the initiation of the induction process, via PKC. We therefore suggest that there may be a link between the serotonergic system and NO-mediated immune responses in the brain. PMID- 9365230 TI - Biotransformation in monkey brain: coupling of sulfation to glutathione conjugation. AB - Phenol sulfotransferase (PST, EC 2.8.2.1) and glutathione-S-transferase (GST, EC 2.5.1.18), the phase II biotransformation enzymes inactivate many exo- and endogenous compounds. The effect of PST substrates (catecholamines, simple phenols, selected phenolic drugs) and PST products (phenolic sulfates) on GST activity was investigated to identify possible interactions between sulfation and glutathione conjugation in the brain. Two soluble forms of PST and two forms of GST were isolated from monkey (Rhesus macacus) brain cortex. Catecholamines, hypertensive and hypotensive drugs which are sulfated by monkey brain PSTs slightly inhibit the activity of brain GSTs. The greatest inhibitory effect was observed with neurotoxic compounds such as 6-OHDA and manganese. The commonly used analgesic drugs inhibit both GST forms. These enzymes are also inhibited by phenacetin, the precursor of paracetamol, and prototype salicylates such as sodium salicylate and acetylsalicylic acid. The effect of simple phenols and their sulfated metabolites on GST activity varies. The obtained results point to a possible interaction between sulfation and glutathione conjugation in vivo since many physiologically, therapeutically and toxicologically active compounds which are sulfated by brain phenol sulfotransferases may be bound by brain glutathione-S-transferases. These compounds may lose their activity (on being bound to GST) and expose the brain to the toxic electrophiles (by decreasing GST activity). PMID- 9365232 TI - A morphological study of the enteric mucosal epithelium in the streptozotocin diabetic mouse. AB - In the acutely diabetic rat, the polyphagia-induced increase in the weight of the small intestine is associated with reported increases in mucosal mass. Whereas, some of the individual mucosal components in the rat have been studied, comparable information for the acutely streptozotocin-diabetic mouse is lacking. A detailed morphological comparison of the epithelium of the small intestinal mucosa in control and untreated streptozotocin-diabetic mice was therefore undertaken. Samples from three small intestinal sites were examined by light and scanning electron microscopy and quantitative data obtained from histological sections. Although the morphological appearance of the small intestine in acutely diabetic mice was similar in many respects to literature accounts for the diabetic rat, infestation with filamentous microorganisms was present in the jejunum and ileum. The quantitative data showed that these sites also contained distorted villi, fewer crypt profiles, more goblet and Paneth cell profiles and a smaller epithelial volume in comparison to controls. These findings may represent differences between the rat and mouse models of streptozotocin-induced diabetes mellitus. PMID- 9365231 TI - Nicotinamide inhibits inducible nitric oxide synthase enzyme activity in macrophages by allowing nitric oxide to inhibit its own formation. AB - Nitric oxide (NO) production by macrophages is mainly regulated by induction of nitric oxide synthase (iNOS) by cytokines and microbial products. Nicotinamide (NIC) inhibits NO production by activated macrophages in a dose dependent manner. NIC also inhibits NOS enzyme activity in extracts from activated macrophages. The inhibition was noncompetitive with L-arginine (Ki 13.37 +/- 4.40 mM, n=3), uncompetitive versus NADPH (Ki 3.06 +/- 0.17 mM, n=3) and tetrahydrobiopterin. Finally, the inhibition by nicotinamide was fully reversed by scavenging NO with hemoglobin. We suggest that NIC acts by allowing NO to inhibit its own formation. PMID- 9365233 TI - Simian virus 40, poliovaccines and human tumors: a review of recent developments. AB - Recently, wild-type SV40 and/or DNA sequences indistinguishable from SV40 have been detected in specific types of human tumors: ependymoma and choroid plexus tumors, mesothelioma, osteosarcoma and sarcoma. The same tumor types will develop in hamsters after injection with SV40. These findings are interesting in themselves for they could shed light on the pathogenesis of these tumors. These findings also have public health implications. SV40 was found to have contaminated the poliovaccines and the adenovaccines from 1955 until 1963, therefore resulting in the inadvertent injection of millions of people with this tumor virus. Moreover, our society pays a high cost for asbestos causality, a carcinogen associated with the development of mesothelioma. In addition to asbestos, the potential impact of finding another possible cause for mesothelioma (i.e., SV40), as well as the possible pathogenic role of the contaminated poliovaccines, has generated considerable public interest and concern. To discuss these recent findings, the NIH (National Institutes of Health) and the FDA (Food and Drug Administration), organized an International Conference at the NIH, Bethesda, MD, January 27-28, 1997. The association of SV40 with human mesothelioma was also discussed in a special session at the IV International Mesothelioma Conference that was held at the University of Pennsylvania, Philadelphia, PA, May 13-16, 1997. The purpose of this review is to summarize data, from the discovery of the contaminated poliovaccines, to the most recent findings presented at the meetings in Bethesda and Philadelphia, to discuss technical and other problems associated with this research, and the potential for using these findings to develop new diagnostic and therapeutic approaches for SV40-associated malignancies. PMID- 9365234 TI - Loss of function and p53 protein stabilization. AB - Wild-type (wt) p53 protein is rapidly degraded, has a short half-life and low intracellular levels. Stabilization of wt p53 protein following an appropriate stimulus (for example DNA damage) is a physiological regulation to increase function. In contrast, stabilization of p53 protein in the absence of a stimulus is always a hallmark of loss of function secondary to a mutation, or interaction with viral or cellular oncoproteins. It is generally accepted that stability of p53 protein depends on its intrinsic biochemical properties such as conformation or protein/protein interactions. However, I will discuss evidence that the stability of p53 is not a consequence of its intrinsic properties, but instead is determined by feedback control of its function. In the absence of an appropriate stimulus, a cell needs to keep p53 levels low, since increased levels can lead to apoptosis. To precisely regulate p53 levels, a cell must sense its level; and sensing its transactivating function, is the simplest way to sense p53. Following an appropriate stimulus (for example, DNA damage), the cell senses a state of 'relative' p53 deficiency and adapts by reducing p53 degradation. When the state of p53 deficiency is a consequence of a mutation or interaction with viral oncoproteins, the cell does not sense p53, and again attempts to adapt by reducing p53 degradation. However, in the latter case, the increase in levels does not restore function, and the adaptation continues until degradation of p53 protein is maximally inhibited. In this case, no further inhibition of degradation is possible after DNA-damage or pharmacological inhibition of proteasomes. Thus lack of wt p53 function always results in increased p53 levels and nonregulation. PMID- 9365235 TI - Cytoplasmic retention of the p53 tumor suppressor gene product is observed in the hepatitis B virus X gene-transfected cells. AB - It has been suggested that hepatitis B virus (HBV) X gene activates X gene expression by disrupting the function of p53 tumor suppressor gene (Takada et al., 1996). To find out their connection, effect of X protein expression on the nuclear localization of p53 protein in human hepatoma cells was examined by the immunofluorescent double-staining technique. The location of transiently expressed p53 protein was examined in X gene-transfected cells, where X protein was detected in the cytoplasm. The nuclear location of transiently-expressed p53 protein was changed to the cytoplasm by X protein co-expression. Endogenous p53 protein was also observed in the cytoplasm by X protein expression. The transcriptional activation domain of X protein and the carboxy-terminal region of p53 protein were found mutually responsible for the cytoplasmic retention of p53 protein in X gene-transfected cells. Therefore, the cytoplasmic retention of p53 protein may be closely correlated to the function of X protein expressed in transfected cells. PMID- 9365236 TI - p53 expression overcomes p21WAF1/CIP1-mediated G1 arrest and induces apoptosis in human cancer cells. AB - The p21WAF1/CIP1 gene, which encodes a cyclin-dependent kinase inhibitor, may be critical for tumor suppressor gene p53-induced cell cycle arrest. The p53 gene is known to regulate G1 checkpoint, which can either induce G1 arrest or initiate apoptosis. To directly examine the role of p21WAF1/CIP1 in the control of p53 function, we have introduced human p21WAF1/CIP1 gene into a p53-deficient human non-small cell lung cancer cell line H1299 using a p21WAF1/CIP1-expressing adenoviral vector (AdCMVp21). Infection with AdCMVp21 resulted in high levels of p21WAF1/CIP1 expression and significantly suppressed the growth of H1299 cells through the G1 arrest of the cell cycle. In contrast, transient expression of the wild-type p53 gene by a recombinant adenoviral vector (AdCMVp53) in H1299 cells induced apoptotic cell death and resulted in a rapid loss of cell viability. We then examined the effects of combined infection with AdCMVp21 and AdCMVp53 on H1299 cells to explore the dominant function of these molecules. Interestingly, introduction of exogenous p53 overcame p21WAF1/CIP1-mediated cell cycle arrest at G1 and induced apoptosis, although viral-transduced p21WAF1/CIP1 expression level was unaffected. These observations suggest that p53 expression converts a p21WAF1/CIP1-mediated growth arrest into apoptosis. The result was repeated with two additional human colon adenocarcinoma cell lines with the different p53 status, mutant p53-expressing DLD-1 and wild-type p53-expressing LoVo, suggesting that this phemonenon is a general event among human cancer cells. Thus, p53 mediated apoptotic pathway is dominant over the growth arrest pathway, indicating that p53 may be an essential upstream mediator of p21WAF1/CIP1 in the regulation of a cell process leading either to growth arrest or to apoptotic suicide. PMID- 9365237 TI - Abnormal telomere dynamics of B-lymphoblastoid cell strains from Werner's syndrome patients transformed by Epstein-Barr virus. AB - The characteristics of B-lymphoblastoid cell strains transformed by Epstein-Barr virus (EBV) from normal individuals and Werner's syndrome (WRN) patients were compared. We continuously passaged cell strains from 28 WRN patients and 20 normal individuals for about 2 years corresponding to over 160 population doubling levels (PDLs). First, the WRN mutation significantly suppressed the immortalization: all the 28 cell strains from WRN patients, as well as 15 out of 20 cell strains from normal individuals, died out before 160 PDLs mostly without developing a significant telomerase activity. The remaining five cell strains from normal individuals became moderately/strongly telomerase-positive and, three of them were apparently immortalized with an infinitively proliferating activity. Second, the monitoring of the telomere length of both normal and WRN cell strains during the culture period suggests that the WRN gene mutation causes abnormal dynamics of the telomere: (1) a significant proportion of WRN cell strains showed drastic shortening or lengthening of telomere lengths during cell passages compared with normal cell strains, and (2) WRN cell strains terminated their life span at a wide range of telomere length (between 3.5 and 18.5 Kbp), whereas normal cell strains terminated within a narrow telomere length range (between 5.5 and 9 Kbp). The chromosomal aberration characteristic of WRN cells, including translocation was confirmed in our experiment. We discussed the correlation between the chromosomal instability, abnormal telomere dynamics and inability of immortalization of the WRN B-lymphobloastoid cell strains. PMID- 9365238 TI - Evidence against a functional site for Bcl-2 downstream of caspase cascade in preventing apoptosis. AB - Apoptotic cell death is driven by ICE family proteases (caspases) and negatively regulated by Bcl-2 family proteins. Although it has been shown that Bcl-2 exerts anti-apoptotic activity by blocking a step(s) leading to the activation of caspases, a role for Bcl-2 and Bcl-xL downstream of the caspase cascade has remained unclear. Here, we show that purified active caspase-3 (CPP32/Yama/apopain) and caspase-1 (ICE) induces apoptosis when microinjected into the cytoplasm of cells, confirming our recent observations, and that the apoptosis is not at all prevented by Bcl-2 and Bcl-xL, which are overexpressed more than sufficiently to prevent Fas-mediated and overexpressed procaspase-1 mediated apoptosis. Thus, Bcl-2 and Bcl-xL do not act downstream of the caspase cascade. PMID- 9365239 TI - Regulation of the tyrosine kinase substrate Eps8 expression by growth factors, v Src and terminal differentiation. AB - SH3-containing proteins are involved in signal transduction by a number of growth factor receptors and in the organization of the cytoskeleton. The recently identified Eps8 protein, which contains an SH3 domain, is coupled functionally and physically to the EGFR and is tyrosine phosphorylated by this receptor and other receptors as well. Here, we examined the regulation of eps8 expression in response to mitogenic or differentiative signals. We show that Eps8 is expressed at low levels in resting fibroblasts, but its expression is strongly induced during activation by serum, phorbol esters and the v-src oncogene. Conversely, expression of Eps8, but not of other EGFR substrates such as Shc or Eps15, is virtually extinguished in non-proliferating, terminally differentiated murine myogenic cells. The putative role of Eps8 protein as a v-Src substrate was analysed in murine fibroblasts and in quail myogenic cells expressing a temperature-sensitive variant of the tyrosine kinase. Tyrosine phosphorylation of Eps8 was detected only at the permissive temperature. A non-myristylated, transformation-defective mutant of v-Src did not phosphorylate Eps8, whereas it phosphorylated Shc. Together, these findings indicate that Eps8 may be a critical substrate of v-Src. They further establish Eps8 as an example of a signal transducer whose expression senses the balance between growth and differentiation and might, therefore, be involved in the determination of the phenotype. PMID- 9365240 TI - Autoregulation of the human N-myc oncogene is disrupted in amplified but not single-copy neuroblastoma cell lines. AB - Amplification of the N-myc gene is a significant adverse prognostic factor in neuroblastoma, a common childhood tumor. In non-transformed cells, myc expression is controlled through an autoregulatory circuit, through which elevated Myc protein levels lead to down-regulation of myc transcription. The precise mechanism of myc gene autoregulation is unknown. Loss of c-myc autoregulation has been documented in transformed cells from a number of different lineages, but N myc autoregulation has not yet been investigated. In neuroblastoma, the increased N-Myc protein produced by amplified tumors would be expected to silence N-myc transcription if the autoregulatory loop were intact. To determine whether N-myc autoregulation is operative in human neuroblastoma, and to localize cis-acting elements which mediate N-myc autosuppression, we transfected a series of N-myc 5' promoter constructs into a panel of human neuroblastoma cell lines carrying one or multiple copies of N-myc. The transfected promoter was equally active in single-copy and amplified lines. Significant promoter activity in the presence of abundant Myc protein in amplified neuroblastoma lines indicates that autoregulation is disabled in this subset of tumors. To investigate whether single-copy lines produce insufficient N-Myc protein to trigger autosuppression yet retain an intact autoregulatory circuit, we transfected neuroblastoma lines with 5' promoter constructs in the presence of a c- or N-myc expression vector. Overexpression of c- or N-Myc resulted in diminution of activity of both the transfected promoter and the endogenous N-myc gene in single-copy, but not amplified lines. Using a series of 5' promoter-deletion minigenes, we localized a cis-acting element required for autoregulation close to the transcription start sites. While the precise mechanism of autosuppression remains unknown, we demonstrated that Myc is incapable of silencing the adenovirus major late promoter (AdMLP) in neuroblastoma cells, indicating that Myc suppression of its own promoter and the AdMLP involve distinct components. These studies provide the first systematic investigation of autoregulation in neuroblastoma, and indicate that single-copy neuroblastoma lines produce insufficient N-Myc protein to activate downstream effector(s) of autosuppression; the autoregulatory circuit is otherwise intact. Amplified lines, in contrast, have lost autoregulation. PMID- 9365241 TI - Pro-apoptotic effect of the c-Abl tyrosine kinase in the cellular response to 1 beta-D-arabinofuranosylcytosine. AB - Treatment of cells with the antimetabolite 1-beta-D-arabinofuranosylcytosine (ara C) and other genotoxic agents is associated with activation of the c-Abl protein tyrosine kinase. The functional role of c-Abl in the response to DNA damage, however, remains unclear. The present studies demonstrate that cells expressing a dominant negative, kinase-inactive c-Abl (K-R) are resistant to killing by ara-C. The expression of c-Abl (K-R) blocked ara-C-induced apoptosis by a mechanism that is at least in part independent of the p53 tumor suppressor. Cells null for c-Abl also exhibited resistance to induction of apoptosis. These findings provide support for a pro-apoptotic function of c-Abl in the response to certain genotoxic drugs. PMID- 9365242 TI - Cells transformed by ODC, c-Ha-ras and v-src exhibit MAP kinase/Erk-independent constitutive phosphorylation of Sos, Raf and c-Jun activation domain, and reduced PDGF receptor expression. AB - While it is known that the constitutive activity of a variety of signal transduction molecules leads to cell transformation, a key unresolved question is whether these wirings converge to a common intermediate(s) that dictates transformation. In this study, we investigated whether NIH3T3 and Rat-1 cells transformed by human ornithine decarboxylase (ODC), c-Ha-rasVal12 and temperature sensitive v-src oncogene display common alteration(s) in the components that relay PDGF-mediated signals in normal fibroblasts. The ras- and ODC-transformed cells did not show constitutively elevated tyrosine phosphorylation of the phospholipase Cgamma-1 (PLCgamma-1), RasGTPase-activating protein (GAP), phosphotyrosine phosphatase Syp, Shc proteins, and phosphatidylinositol 3-kinase (PI3-K) or activation of the MAP kinase (Erk1 and Erk2), p70 S6 kinase or the Janus protein tyrosine kinase (JAK) and signal transducer and activator of transcription (STAT) protein-1 pathways. Instead, the Ras nucleotide exchange factor Sos-1 and Raf-1 kinase exhibited constitutive phosphorylations, as deduced from their electrophoretic mobility shifts in polyacrylamide gels. Hence a kinase distinct from Erk1 and Erk2, previously known to feedback phosphorylate Sos-1 and Raf-1, is responsible for the phosphorylation of these molecules in the transformants. We also demonstrate that the ras- and ODC-transformed cells exhibit loss of both the PDGF alpha- and beta-receptors, while the v-Src transformants show a predominant reduction in the beta-receptors. Moreover, all the transformed cell lines were found to display a constitutive increase in phosphorylation of c-Jun on serines 63 and 73, which appears to be governed by an as yet unknown kinase. PMID- 9365244 TI - KSHV ORF K9 (vIRF) is an oncogene which inhibits the interferon signaling pathway. AB - Kaposi's sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus linked to the development of Kaposi's sarcoma and a rare B cell lymphoma, primary effusion lymphoma. The KSHV gene ORF K9 encodes vIRF which is a protein with low but significant homology to members of the interferon (IFN) regulatory factor (IRF) family responsible for regulating intracellular interferon signal transduction (Moore PS, Boshoff C, Weiss RA and Chang Y. (1996). Science, 274, 1739-1744). vIRF inhibits IFN-beta signal transduction as measured using an IFN-responsive ISG54 reporter construct co-transfected with ORF K9 into HeLa and 293 cells. vIRF also suppresses genes under IFN regulatory control as shown by inhibition of the IFN-beta inducibility of p21WAF1/CIP1, however, no direct DNA-binding or protein protein interactions characteristic for IRF repressor proteins were identified. Stable transfectant NIH3T3 clones expressing vIRF grew in soft agar and at low serum concentrations, lost contact inhibition and formed tumors after injection into nude mice indicating that vIRF has the properties of a viral oncogene. Since vIRF is primarily expressed in KSHV-infected B cells, not KS spindle cells, this study suggests that vIRF is a transforming oncogene active in B cell neoplasias that may provide a unique immune escape mechanism for infected cells. This data is consistent with tumor suppressor pathways serving a dual function as host cell antiviral pathways. PMID- 9365243 TI - Cloning and developmental expression of the murine homolog of the acute leukemia proto-oncogene AF4. AB - AF4 is the 4q21 gene involved in the acute lymphoblastic leukemia associated t(4;11)(q21;q23) where it forms a fusion gene with MLL. In order to gain insight into AF4's role in leukemogenesis we have studied its functional domains and expression pattern during murine development. We have cloned the murine homolog, Af4. We have demonstrated that 5' half of Af4 encodes a region with transcriptional transactivation activity which is disrupted by the t(4;11) in human leukemias. We have also localized the murine AF4 protein to the nucleus supporting a role for AF4 in transcription. The developmental expression pattern of Af4 was determined in situ hybridization and suggests Af4 plays an important role in the development of the hematopoietic, cardiovascular, skeletal and central nervous systems. A repeating pattern of Af4 expression in development is down-regulation with differentiation of a tissue. Among the cell types where this pattern of down-regulation is noted are B-lymphocytes. These findings raise the possibility that the disruption of normal AF4 function by the translocation may contribute to leukemogenesis. PMID- 9365245 TI - Expression of the neoplastic phenotype by human thyroid carcinoma cell lines requires NFkappaB p65 protein expression. AB - We have investigated the role of the NFkappaB complex in the process of thyroid carcinogenesis by analysing thyroid carcinoma cell lines. A significant increase in p65 NFkappaB mRNA and protein expression, compared to normal thyroid cultures or tissue, was found in all of the cancer cell lines. Conversely, only a modest increase in the p50 NFkappaB mRNA and protein was found in most, but not all carcinoma cell lines. The block of p65 protein synthesis with specific antisense oligonucleotides greatly reduced the ability of two undifferentiated carcinoma cell lines to form colonies in agar and reduced their growth rate. On the other hand, no effect was observed in the same cell lines when treated with p50 specific antisense oligonucleotides. These inhibitory effects seem to be mediated by the suppression of c-myc gene expression, since treatment with antisense oligonucleotides for p65 gene interfered negatively with c-myc gene expression. Our results indicate that activation of the NFkappaB complex by overexpression of p65 plays a critical role in the process of thyroid cell transformation. PMID- 9365246 TI - Abnormal erythropoietin (Epo) gene expression in the murine erythroleukemia IW32 cells results from a rearrangement between the G-protein beta2 subunit gene and the Epo gene. AB - Abnormal production of erythropoietin (Epo) has been described in several human and murine erythroleukemia. The murine IW32 cell line is derived from an F-MuLV induced erythroleukemia. An autocrine Epo production due to the rearrangement of one Epo allele has been previously described (Beru et al., 1989). However, the exact mechanism leading to the transcriptional activation of the abnormal Epo gene was unknown. In this study, we show that this deregulated expression results from a deletion within chromosome 5. The Epo gene in the abnormal allele is under the control of the G-protein beta2 subunit gene promoter and the expressed mRNA results from the fusion of the non coding exon 1 of the G-protein beta2 subunit gene to a truncated Epo exon 1 gene. This resulting abnormal cDNA allows the expression of a normal Epo protein. PMID- 9365247 TI - Non-canonical sequence elements in the promoter structure. Cluster analysis of promoters recognized by Escherichia coli RNA polymerase. AB - Nucleotide sequences of 441 promoters recognized by Escherichia coli RNA polymerase were subjected to a site-specific cluster analysis based on the hierarchical method of classification. Five regions permitting promoter subgrouping were identified. They are located at -54 +/- 4, -44 +/- 3, -35 +/- 3 (-35 element), -29 +/- 2 and -11 +/-4 (-10 element). Promoters were independently subgrouped on the basis of their sequence homology in each of these regions and typical sequence elements were determined. The putative functional significance of the revealed elements is discussed on the basis of available biochemical data. Those promoters that have a high degree of homology with the revealed sequence elements were selected as representatives of corresponding promoter groups and the presence of other sequence motifs in their structure was examined. Both positive and negative correlations in the presence of particular sequence motifs were observed; however, the degree of these interdependencies was not high in all cases, probably indicating that different combinations of the signal elements may create a promoter. The list of promoter sequences with the presence of different sequence elements is available on request by Email: ozoline@venus.iteb. serpukhov.su. PMID- 9365248 TI - Comparison of chromosomal DNA composing timeless in Drosophila melanogaster and D. virilis suggests a new conserved structure for the TIMELESS protein. AB - Two proteins, TIM and PER, physically interact to control circadian cycles of tim and per transcription in Drosophila melanogaster. In the present study the structure of TIM protein expressed by D. virilis was determined by isolation and sequence analysis of genomic DNA (gDNA) corresponding to the D. virilis tim locus (v tim ). Comparison of v tim and m tim gDNA revealed high conservation of the TIM protein. This contrasts with poor sequence conservation previously observed for the TIM partner protein PER in these species. Inspection of the v tim sequence suggests an alternative structure for most TIM proteins. Sequences forming an intron in a previously characterized D. melanogaster tim cDNA appear to be most often translated to produce a longer TIM protein in both species. The N-terminal sequence of vTIM and sequence analysis of genomic DNA from several strains of D. melanogaster suggest that only one of two possible translation initiation sites found in tim mRNA is sufficient to generate circadian rhythms in D. melanogaster. TIM translation may be affected by multiple AUG codons that appear to have been conserved in sequences composing the 5'-untranslated tim mRNA leader. PMID- 9365249 TI - A spermidine-induced conformational change of long-armed hammerhead ribozymes: ionic requirements for fast cleavage kinetics. AB - The catalytic activity of the trans cleaving hammerhead ribozyme 2as-Rz12, with long antisense flanks of 128 and 278 nt, was tested under a wide range of different reaction conditions for in vitro cleavage of a 422 nt RNA transcript derived from human immunodeficiency virus type 1 (HIV-1). Depending on the reaction conditions, in vitro cleavage rates varied by a factor of approximately 100. Increasing concentrations of magnesium up to 1 M were found to enhance the reaction. Sodium when added simultaneously with magnesium showed an inhibitory effect on the cleavage reaction. Addition of sodium during pre-annealing, however, produced a stimulating effect. It was found that the additional inclusion of spermidine during pre-annealing further increased the reaction rate markedly. In accordance with accelerated cleavage, it was possible to identify a distinct, spermidine-induced conformer of the ribozyme-substrate complex. Under the most favourable conditions cleavage rates of 1/min were obtained, which are in the range of rates obtained for conventional hammerhead ribozymes with short antisense flanks. A comparison of thermodynamic data for short- and long-armed hammerhead ribozymes suggested that the activation entropy became unfavourable when helices I and III formed a long chain ribozyme-substrate complex. We conclude that in the absence of spermidine folding into the active conformation is impaired by increased friction of long helices, resulting in relatively low cleavage rates in vitro. PMID- 9365250 TI - Conformation of the 3'-end of beet necrotic yellow vein benevirus RNA 3 analysed by chemical and enzymatic probing and mutagenesis. AB - Secondary structure-sensitive chemical and enzymatic probes have been used to produce a model for the folding of the last 68 residues of the 3'-non-coding region of beet necrotic yellow vein benevirus RNA 3. The structure consists of two stem-loops separated by a single-stranded region. RNA 3-derived transcripts were produced containing mutations which either disrupted base pairing in the helices or maintained the helices but with alterations in the base pairing scheme. Other mutants contained substitutions in single-stranded regions (loops or bulged sequences). With a few exceptions all three types of mutation abolished RNA 3 replication in vivo, suggesting that both secondary structure and specific sequences are required for efficient recognition of the 3'-terminal region of RNA 3 by viral RNA-dependent RNA polymerase. PMID- 9365251 TI - Homeodomain-DNA interactions of the Pho2 protein are promoter-dependent. AB - The homeodomain (HD) is a conserved sequence-specific DNA-binding motif found in many eukaryotic transcriptional regulatory proteins. Despite the wealth of in vitro data on the mechanism HD proteins use to bind DNA, comparatively little is known about the roles of individual residues in these domains in vivo . The Saccharomyces cerevisiae Pho2 protein contains a HD that shares significant sequence identity with the Drosophila Engrailed protein. We have used the co crystal structure of Engrailed as a model to predict how Pho2 might contact DNA and have examined how individual residues of the Pho2 HD contribute to transcriptional activation in vivo and to DNA binding in vitro. Our results demonstrate that Pho2 and Engrailed share many similar DNA-binding characteristics. However, our results also show that some highly conserved residues, which contact the DNA in many HD structures, make relatively small contributions to the DNA-binding affinity and in vivo activity of the Pho2 protein. We also show that the N-terminal arm of the Pho2 HD is a critical component in determining the DNA-binding specificity of the protein and that the requirements for residues in the N-terminal arm are promoter-dependent for Pho2 transcriptional activation and DNA binding. PMID- 9365252 TI - Human genes encoding U3 snRNA associate with coiled bodies in interphase cells and are clustered on chromosome 17p11.2 in a complex inverted repeat structure. AB - Coiled bodies (CBs) are nuclear organelles whose morphological structure and molecular composition have been conserved from plants to animals. Furthermore, CBs are often found to co-localize with specific DNA loci in both mammalian somatic nuclei and amphibian oocytes. Much as rDNA sequences are called nucleolus organizers, we term these coiled body-associated sequences 'coiled body organizers' (CBORs). The only sequences that have been shown to be CBORs in human cells are the U1, U2 and histone gene loci. We wanted to determine whether other snRNA genes might also act as CBORs. In this paper we show that human U3 genes (the RNU3 locus) preferentially associate with CBs in interphase cells. In addition, we have analyzed the genomic organization of the RNU3 locus by constructing a BAC and P1 clone contig. We found that, unlike the RNU1 and RNU2 loci, U3 genes are not tandemly repeated. Rather, U3 genes are clustered on human chromosome 17p11.2, with evidence for large inverted duplications within the cluster. Thus all of the CBORs identified to date are composed of either tandemly repeated or tightly clustered genes. The evolutionary and cell biological consequences of this type of organization are discussed. PMID- 9365253 TI - An efficient and economic site-specific deuteration strategy for NMR studies of homologous oligonucleotide repeat sequences. AB - We describe herein the use of a 2H-labeling strategy to achieve specific assignments of considerably overlapped cross peaks in the 1H-NMR spectrum of a DNA trinucleotide repeat sequence. Our strategy focuses on site-specific 2H labeling of base moieties to simplify the NMR spectral regions which contain the major portion of the structural information. To achieve efficient preparation of 2H8- or 2H6-labeled DNA and RNA nucleosides and nucleotides, the existing synthetic and purification procedures were significantly improved. Our experiments demonstrate that pyrimidine H6 deuteration reactions may be carried out using non-deuterated base reagents with DMSO-d6 as a 2H donor. These reactions are simple and economic to perform and produce base deuterated nucleosides and nucleotides in high yield. The 2H-labeled residues have been incorporated into oligonucleotides with minor modifications of the existing reaction conditions. Using the homologous CGG repeat sequence, d(CGG)5, as an example, the effectiveness of the site-specific base deuteration strategy is demonstrated. In the otherwise extensively overlapped spectra of d(CGG)5, 2H labeling has permitted unambiguous identification of a sequential connectivity at a central CG step and confirmation of several other NOE assignments. This information is critical for elucidation of the structure and the folding of the CGG repeat sequences and will contribute to the intensive effort to understand the mechanisms of triplet expansion, which has been implicated in the development of a number of hereditary neurodegenerative diseases. In addition to the two dimensional spectral simplification in a key spectral region using site-specific 2H8/2H6-labeling, the potential applications of the prescribed strategy in homonuclear three dimensional experiments are also discussed. PMID- 9365254 TI - Identification and developmental characterization of a novel Y-box protein from Drosophila melanogaster. AB - The Y-box proteins are a family of highly conserved nucleic acid binding proteins which are conserved from bacteria to human. In this report we have identified a new member of this family from Drosophila melanogaster. Degenerate-PCR was used to identify a conserved region within the highly conserved cold-shock domain (CSD) of Y-box proteins. Subsequently, the cDNA for this gene was sequenced, and the identified open reading frame was named ypsilon schachtel (yps). The expression pattern of yps indicates that this gene is expressed throughout development with the highest level of expression found in adult flies. In situ hybridization shows that the yps mRNA is maternally loaded into the egg cytoplasm. In addition, there appears to be expression of yps mRNA in mesodermal tissue during embryogenesis. YPS, while containing a conserved CSD, is novel in that it completely lacks the alternating acidic and basic regions found in the C terminus of the other vertebrate eukaryotic Y-box proteins. The CSD of yps was purified and gel-shift analysis showed that this domain can interact with RNA. We predict that YPS would be an RNA-binding protein due to these results and the motifs which have been identified within the amino acid sequence. PMID- 9365255 TI - Covalent cross-linking of duplex DNA using 4-thio-2'-deoxyuridine as a readily modifiable platform for introduction of reactive functionality into oligonucleotides. AB - Full details of the template-directed covalent cross-linking of duplex oligodeoxynucleotides are presented. 4-Thio-2'-deoxyuridine was incorporated synthetically into a 17mer oligodeoxynucleotide, and the thiocarbonyl group of the modified base was alkylated with a variety of alpha-bromoacetyl-derivatized diamines. Covalent cross-linking was initiated by annealing the electrophilic probe oligomers with their complementary sequences, where a dG base was targeted at the position complementary to the modified 4-thio-2'-deoxyuridine. The sequence selectivity of cross-link formation as a function of tether topology and rigidity was examined, and the thermal stability of the modified duplexes was measured by UV melting experiments. PMID- 9365257 TI - Dynamics in the isomerization of intramolecular DNA triplexes in supercoiled plasmids. AB - We report here kinetic and thermodynamic studies on differential isomerization of intramolecular Pyr*Pur.Pyr triplexes in supercoiled plasmids. Two structural isomers of the triplex exist: one with the 3'-half of the Pyr strand as the third strand (H-y3 form) and the other with the 5'-half as the third strand (H-y5 form). The relative populations of the two triplex isomers was determined using the chemical probe with diethyl pryrocarbonate as a function of incubation time. The results demonstrated that triplexes were formed rapidly after a pH change from pH 8.0 to 5.0 and that the initial population of the two isomers exponentially changed with incubation time to reach true thermodynamic equilibrium with a time constant of 0.6-10 h, depending on temperature and the presence of Mg2+. The results clearly demonstrated that interconversion occurs between the two isomers and that the presence of Mg2+ generally retarded the interconversion rates. Kinetic and thermodynamic analyses of the relative populations of the two isomers revealed that the apparent energy barrier for transition from duplex to the H-y3 form is higher than that to the H-y5 form, but H-y3 is more stable in enthalpy terms than H-y5. Therefore, H-y3 is kinetically inferior but thermodynamically favored at higher supercoil levels in plasmids. The presence of Mg2+ resulted in both a kinetic and a thermodynamic preference for H-y5 formation, relative to the H-y3 form. PMID- 9365258 TI - Information transfer from DNA to peptide nucleic acids by template-directed syntheses. AB - Peptide nucleic acids (PNAs) are analogs of nucleic acids in which the ribose phosphate backbone is replaced by a backbone held together by amide bonds. PNAs are interesting as models of alternative genetic systems because they form potentially informational base paired helical structures. Oligocytidylates have been shown to act as templates for formation of longer oligomers of G from PNA G2 dimers. In this paper we show that information can be transferred from DNA to PNA. DNA C4T2C4 is an efficient template for synthesis of PNA G4A2G4 using G2 and A2 units as substrates. The corresponding synthesis of PNA G4C2G4 on DNA C4G2C4 is less efficient. Incorporation of PNA T2 into PNA products on DNA C4A2C4 is the least efficient of the three reactions. These results, obtained using PNA dimers as substrates, parallel those obtained using monomeric activated nucleotides. PMID- 9365256 TI - The yeast SEN1 gene is required for the processing of diverse RNA classes. AB - A single base change in the helicase superfamily 1 domain of the yeast Saccharomyces cerevisiae SEN1 gene results in a heat-sensitive mutation that alters the cellular abundance of many RNA species. We compared the relative amounts of RNAs between cells that are wild-type and mutant after temperature shift. In the mutant several RNAs were found to either decrease or increase in abundance. The affected RNAs include tRNAs, rRNAs and small nuclear and nucleolar RNAs. Many of the affected RNAs have been positively identified and include end matured precursor tRNAs and the small nuclear and nucleolar RNAs U5 and snR40 and snR45. Several small nucleolar RNAs co-immunoprecipitate with Sen1 but differentially associate with the wild-type and mutant protein. Its inactivation also impairs precursor rRNA maturation, resulting in increased accumulation of 35S and 6S precursor rRNAs and reduced levels of 20S, 23S and 27S rRNA processing intermediates. Thus, Sen1 is required for the biosynthesis of various functionally distinct classes of nuclear RNAs. We propose that Sen1 is an RNA helicase acting on a wide range of RNA classes. Its effects on the targeted RNAs in turn enable ribonuclease activity. PMID- 9365259 TI - Information transfer from peptide nucleic acids to RNA by template-directed syntheses. AB - Peptide nucleic acids (PNAs) are uncharged analogs of DNA and RNA in which the ribose-phosphate backbone is substituted by a backbone held together by amide bonds. PNAs are interesting as models of alternative genetic systems because they form potentially informational base paired helical structures. A PNA C10 oligomer has been shown to act as template for efficient formation of oligoguanylates from activated guanosine ribonucleotides. In a previous paper we used heterosequences of DNA as templates in sequence-dependent polymerization of PNA dimers. In this paper we show that information can be transferred from PNA to RNA. We describe the reactions of activated mononucleotides on heterosequences of PNA. Adenylic, cytidylic and guanylic acids were incorporated into the products opposite their complement on PNA, although less efficiently than on DNA templates. PMID- 9365260 TI - A gene trap approach to isolate mammalian genes involved in the cellular response to genotoxic stress. AB - Treatment of cells with DNA damaging agents leads to induction of a variety of genes involved in different cellular processes. We have applied a lacZ-based gene trap strategy to search for new mammalian genes induced by genotoxic stress. A population of 32 x 10(3) neo r clones stably transfected with a gene trap vector was obtained, stained with fluorescein di-beta-d-galactopyranoside and analyzed by flow activated cell sorting and replica plating. This strategy allowed isolation of 30 neo r 'putative inducible' cell lines expressing lacZ only after a DNA damaging treatment. For three clones the site of integration and the degree of inducibility after UV treatment were determined by Southern blot and beta galactosidase measurement respectively. One cell line (clone VI) showed a single integration site and a reproducible 3-fold induction of beta-galactosidase activity following UV irradiation. Fused transcripts were isolated from induced cells and a portion of the trapped gene was amplified by rapid amplification of cDNA ends. Sequence analysis and comparison with available gene and protein databanks revealed that the gene was novel. PMID- 9365262 TI - Hydration of the dTn.dAn x dTn parallel triple helix: a Fourier transform infrared and gravimetric study correlated with molecular dynamics simulations. AB - We present a comparative analysis of the water organization around the dTn.dAn x dTn triple helix and the Watson-Crick double helix dTn.dAn respectively by means of gravimetric measurements, infrared spectroscopy and molecular dynamics simulations. The hydration per nucleotide determined by gravimetric and spectroscopic methods correlated with the molecular dynamics simulations shows that at high relative humidity (98% RH) the triple helix is less solvated than the duplex (17 +/- 2 water molecules per nucleotide instead of 21 +/-1). The experimental desorption curves are different for both structures and indicate that below 81% RH the triplex becomes more hydrated than the duplex. At this RH the FTIR spectra show the emergence of N-type sugars in the adenosine strand of the triplex. When the third strand is bound in the major groove of the Watson Crick duplex molecular dynamics simulations show the formation of a spine of water molecules between the two thymidine strands. PMID- 9365261 TI - Modification of human U4 RNA requires U6 RNA and multiple pseudouridine synthases. AB - Small nuclear RNAs (snRNA), cofactors in the splicing of pre-mRNA, are highly modified. In this report the modification of human U4 RNA was studied using cell extracts and in vitro synthesized, and therefore unmodified, U4 RNA. The formation of pseudouridine (Psi) at positions 4, 72 and 79 in U4 RNA was dependent on an RNA-containing cofactor, since the activities in the extracts were micrococcal nuclease (MN) sensitive. Extracts were fractionated on glycerol gradients and there was a broad peak of reconstitution activity centered at 14 S. Reconstitution was not due to additional enzymatic activity, since the peak fraction was MN sensitive. Oligodeoxynucleotide-mediated RNase H digestion of U6 RNA in the extracts inhibited formation of Psi in U4 RNA. From glycerol gradient analysis we determined that exogenously added U4 RNA that is associated with U6 RNA (sedimentation velocity 16 S) was significantly higher in Psi content than U4 RNA not associated with U6 RNA (8 S). Competitive inhibitors of Psi synthases, 5 fluorouridine-containing (5-FU) wild-type and mutant U4 RNAs, were used to investigate formation of Psi in U4 RNA. Deletions and point mutations in these 5 FU-containing U4 RNAs affected their ability to inhibit Psi synthase in vitro. With the aid of these potent inhibitors it was determined that at least two separate activities modify the uridines at these positions. PMID- 9365263 TI - Allele identification using immobilized mismatch binding protein: detection and identification of antibiotic-resistant bacteria and determination of sheep susceptibility to scrapie. AB - A novel method for detection and identification of specific alleles has been developed utilizing immobilized mismatch binding protein (IMBP). The assay involves the use of biotin-labeled probes, which are prepared by PCR amplification of cloned fragments with known sequence. The use of probes avoids many of the problems associated with the extreme sensitivity of IMBP assays to errors in PCR amplification. The method can be used to monitor PCR fidelity and to genotype both diploid and haploid organisms and has been used to distinguish rifampicin-sensitive and -resistant strains of Mycobacterium tuberculosis and to detect and distinguish two alleles of the sheep prion protein gene involved in susceptibility to scrapie. PMID- 9365264 TI - Extensive RNA editing and possible double-stranded structures determining editing sites in the atpB transcripts of hornwort chloroplasts. AB - Three nonsense codons and an unusual initiation codon were located within the putative coding region of the atpB gene of chloroplast DNA of the hornwort Anthoceros formosae. Nucleotide sequencing of cDNA prepared from transcripts revealed extensive RNA editing. The unusual initiation codon ACG was changed to AUG and three nonsense codons were converted into sense codons. In total 15 C residues of the genomic DNA were replaced by U residues in the mRNA sequences, while 14 U residues were replaced by C residues. This is the highest number of editing events for a chloroplast mRNA reported so far. Partial editing was also shown in a cDNA clone where 23 sites were edited but six sites remained unedited, representing the existence of premature mRNA. The expected two-dimensional structure of the mRNA shows the existence of a sequence complementary to every editing site, which can produce continuous base pairing longer than 5 bp, suggesting that mispairing in the double strand is the site determinant for RNA editing in Anthoceros chloroplasts. Comparison of the cDNA sequence with other chloroplast genes suggests that the mechanism arose in the first land plants and has been reduced during evolution. PMID- 9365265 TI - An improved divergent synthesis of comb-type branched oligodeoxyribonucleotides (bDNA) containing multiple secondary sequences. AB - The divergent synthesis of branched DNA (bDNA) comb structures is described. This new type of bDNA contains one unique oligonucleotide, the primary sequence, covalently attached through a comb-like branch network to many identical copies of a different oligonucleotide, the secondary sequence. The bDNA comb structures were assembled on a solid support and several synthesis parameters were investigated and optimized. The bDNA comb molecules were characterized by polyacrylamide gel electrophoretic methods and by controlled cleavage at periodate-cleavable moieties incorporated during synthesis. The developed chemistry allows synthesis of bDNA comb molecules containing multiple secondary sequences. In the accompanying article we describe the synthesis and characterization of large bDNA combs containing all four deoxynucleotides for use as signal amplifiers in nucleic acid quantification assays. PMID- 9365266 TI - Chemical synthesis and characterization of branched oligodeoxyribonucleotides (bDNA) for use as signal amplifiers in nucleic acid quantification assays. AB - The divergent synthesis of bDNA structures is described. This new type of branched DNA contains one unique oligonucleotide, the primary sequence, covalently attached through a comb-like branching network to many identical copies of a different oligonucleotide, the secondary sequence. The bDNA comb molecules were assembled on a solid support using parameters optimized for bDNA synthesis. The chemistry was used to synthesize bDNA comb molecules containing 15 secondary sequences. The bDNA comb molecules were elaborated by enzymatic ligation into branched amplification multimers, large bDNA molecules (a total of 1068 nt) containing an average of 36 repeated DNA oligomer sequences, each capable of hybridizing specifically to an alkaline phosphatase-labeled oligonucleotide. The bDNA comb molecules were characterized by electrophoretic methods and by controlled cleavage at periodate-cleavable moieties incorporated during synthesis. The branched amplification multimers have been used as signal amplifiers in nucleic acid quantification assays for detection of viral infection. It is possible to detect as few as 50 molecules with bDNA technology. PMID- 9365267 TI - Synthesis and two-dimensional electrophoretic analysis of mixed populations of circular and linear RNAs. AB - Spontaneous cleavage of the less abundant form of tobacco ringspot virus satellite RNA is readily reversible. Capitalizing on earlier observations by Feldstein and Bruening that small 'mini-monomer' RNAs derived from this molecule and containing little more than covalently attached ribozyme and substrate cleavage products are able to efficiently circularize, we have constructed a series of self-circularizing RNAs of precisely known size. Mixtures of linear and circular RNAs synthesized in vitro and containing 225-1132 nt could be completely resolved using a novel two-dimensional denaturing polyacrylamide gel electrophoresis system. Similar analyses of a complex mixture of coconut cadang cadang viroid RNAs revealed the presence of relatively large amounts of a previously undescribed 'fast-slow' heterodimeric RNA species in infected palms. Only a single DNA template is required to prepare each pair of circular and linear RNA markers. PMID- 9365268 TI - A rapid, quantitative and inexpensive method for detecting apoptosis by flow cytometry in transiently transfected cells. AB - We describe a rapid and quantitative flow cytometric method for determining the apoptotic or anti-apoptotic potential of a gene in various cell types. A plasmid carrying green fluorescent protein (GFP) is co-transfected with an expression vector encoding the gene of interest. Subsequently cells are stained with propidium iodide and, utilising flow cytometry, transfected, GFP-expressing single cells are detected and apoptotic cells in this population are identified by their DNA content of <2 N. The method detects apoptosis as reliably as established methods using in situ nick-end labelling but is faster, easier and less expensive. PMID- 9365269 TI - A novel method to isolate cells with conditional gene expression using fluorescence activated cell sorting. AB - An inducible expression system using control elements of the tetracycline resistance operon has recently shown promise for conditional gene expression of any gene of interest. However, intensive screening of multiple independent clones is often required to find cell lines with optimal induction characteristics. By coupling expression of the gene of interest with a fluorescent marker, we have developed a novel fluorescence activated cell sorting (FACS) based strategy to isolate cells with desirable expression characteristics, thus alleviating the laborious isolation and analysis of multiple independent clones. PMID- 9365270 TI - Post-Golgi biosynthetic trafficking. AB - Eukaryotic cells have developed complex machineries to distribute proteins and lipids from the Golgi complex. Contrary to what has originally been postulated, delivery of proteins to the cell surface is not a simple bulk flow process but involves sorting into distinct pathways from the trans-Golgi network. Here we describe the various routes emerging from the trans-Golgi network in different cell types, and we discuss the mechanisms that mediate sorting into these pathways. While much remains to be learned about these sorting mechanisms, it is apparent that a number of pathways previously believed to be restricted to certain cell types might be used more commonly. PMID- 9365271 TI - Ezrin: a protein requiring conformational activation to link microfilaments to the plasma membrane in the assembly of cell surface structures. AB - The cortical cytoskeleton of eucaryotic cells provides structural support to the plasma membrane and also contributes to dynamic processes such as endocytosis, exocytosis, and transmembrane signaling pathways. The ERM (ezrin-radixin-moesin) family of proteins, of which ezrin is the best studied member, play structural and regulatory roles in the assembly and stabilization of specialized plasma membrane domains. Ezrin and related molecules are concentrated in surface projections such as microvilli and membrane ruffles where they link the microfilaments to the membrane. The present knowledge about ezrin is discussed from an historical perspective. Both biochemical and cell biological studies have revealed that ezrin can exist in a dormant conformation that requires activation to expose otherwise masked association sites. Current results indicate that activated ezrin monomers or head-to-tail oligomers associate directly with F actin through a domain in its C terminus, and with the membrane through its N terminal domain. The association of ezrin with transmembrane proteins can be direct, as in the case of CD44, or indirect through EBP50. Other binding partners, including the regulatory subunit of protein kinase A and rho-GDI, suggest that ezrin is an integral component of these signaling pathways. Although the membrane-cytoskeletal linking function is clear, further studies are necessary to reveal how the activation of ezrin and its association with different binding partners is regulated. PMID- 9365272 TI - Xenopus Ran-binding protein 1: molecular interactions and effects on nuclear assembly in Xenopus egg extracts. AB - Ran is a nuclear GTPase implicated in nucleocytoplasmic transport, the maintenance of nuclear structure, mRNA processing, and cell cycle regulation. By two-hybrid interaction in yeast, we have identified a Xenopus homologue of Ran binding protein 1 (RanBP1). Xenopus RanBP1 interacts specifically with the GTP bound form of Ran and forms complexes in Xenopus egg extracts with Ran, importin beta/karyopherin-beta and importin-alpha/karyopherin-alpha, but not p10, p120/RanBP7, RanBP2 or other nucleoporins. These complexes may play roles in the recycling of Ran and importins/karyopherins during nucleocytoplasmic transport. Increased concentrations of RanBP1 stabilise an interaction between Ran and RCC1 in egg extracts, inhibiting the exchange activity of RCC1 towards Ran. Under these conditions, the assembly of nuclei from chromatin is dramatically affected: the nuclei do not assemble a lamina and become very small with homogeneously condensed chromatin. They fail to actively import proteins and do not undergo DNA replication. By field emission in-lens scanning electron microscopy, we show that these nuclei have an intact nuclear envelope containing pore complexes, but the envelope is highly convoluted. However, RanBP1 does not directly inhibit nuclear protein import in assembled nuclei. These results suggest that RCC1 and/or Ran have a function early in nuclear assembly that is disrupted by RanBP1. PMID- 9365273 TI - A nuclear matrix-associated high molecular mass nuclear antigen, HMNA, of chicken and marked decrease of its immunoreactivity during the progression of S phase. AB - A hnRNP-free nuclear matrix prepared from chicken MSB-1 cells was used to raise monoclonal antibodies. The monoclonal antibodies 2H3 and 3B7 showed identical non homogeneous immunofluorescence staining patterns of nuclei in MSB-1 cells and chicken embryonic fibroblasts. In a synchronized culture of MSB-1 cells, the immunoreactivity of nuclei with 2H3, but not with 3B7, antibody decreased markedly during the progression of S phase, but returned to the normal level at the next G1 phase. When cells were treated with Triton X-100 prior to fixation with paraformaldehyde or cells were fixed in methanol, nuclei were reactive with 2H3 antibody throughout the S phase. Both 2H3 and 3B7 antibodies recognized a high molecular mass nuclear antigen (HMNA) of approximately 550 kDa, which was associated with the nuclear matrix. HMNA was resistant to extraction with 0.5 M NaCl from the nuclei at the G1/S boundary but became extractable by the end of S phase. A cDNA clone, pBHB36, containing a partial sequence for HMNA was isolated by immunoscreening as a double positive clone with 2H3 and 3B7 antibodies. The deduced 1,150 residue-long sequence of pBHB36 shows no homology with any molecules in the nucleotide and protein sequence databases, and contains different epitope regions for 2H3 and 3B7 antibodies. A possibility of hydrophobic association of HMNA with nuclear protein(s) during the progression of S phase is discussed. PMID- 9365274 TI - The AMF-R tubule is a smooth ilimaquinone-sensitive subdomain of the endoplasmic reticulum. AB - Autocrine motility factor receptor (AMF-R) is a marker for a distinct smooth membranous tubule. Ilimaquinone (IQ) is a sea sponge metabolite which induces the complete vesiculation of the Golgi apparatus and we show here that the addition of IQ to MDCK cells also results in the disruption of the AMF-R tubule. By immunofluorescence microscopy, the resultant punctate AMF-R label resembles the products of IQ-mediated vesiculation of the trans-Golgi network, however, the two labels can be distinguished by confocal microscopy. AMF-R tubule fragmentation occurs after nocodazole or taxol treatment of the cells demonstrating that the action of IQ on AMF-R tubules is not related to the ability of IQ to depolymerize microtubules. IQ activity is therefore not Golgi-specific. Electron microscopy of IQ-treated cells reveals that AMF-R is distributed to fenestrated networks of narrow interconnected tubules which are distinguishable from the uniform Golgi derived vesicles and morphologically equivalent to smooth ER. Distinct fenestrations are visible in incompletely fragmented tubules which may represent intermediates in the fragmentation process. Smooth AMF-R labeled tubules exhibit continuity with rough ER cisternae and IQ selectively targets smooth and not rough ER. AMF-R tubules can be distinguished from the intermediate compartment labeled for ERGIC-53 by confocal microscopy and thus constitute a distinct IQ sensitive subdomain of the smooth ER. PMID- 9365275 TI - Overexpression of MAP4 inhibits organelle motility and trafficking in vivo. AB - We previously prepared cell lines that inducibly overexpress MAP4, a microtubule (MT)-associated protein widely expressed in non-neuronal cells. Overexpression of either the full-length MAP4 molecule or its MT-binding domain, MTB, stabilized MTs and retarded cell growth, suggesting that overexpressed MAP4 impacts on MT dependent functions in vivo. To test this hypothesis, we examined MT-based vesicle movements in living cells, using high resolution DIC microscopy. Overexpression of either MAP4 or MTB yielded a dose-dependent reduction in the frequency of MT-dependent organelle movements, relative to control cells. At steady state, both MAP4- and MTB-overexpressing cells showed unusual distributions of transferrin, LDL, dextran, and Golgi elements, as compared to control cells. MAP4 preferentially inhibited receptor-dependent uptake and degradation of LDL, and repositioning of Golgi elements after disruption by the drug, brefeldin A. L-MOCK cells treated with Taxol to stabilize the MTs to an extent equivalent to MAP4 overexpression did not show similar inhibition of vesicle motility or organellar trafficking, suggesting that deficits in organelle movements in vivo represent a direct effect of the presence of MAP4 or MTB, rather than an indirect effect of the stabilization of MTs by overexpressed MAP constructs. Our results show that MAP4 has the capacity to affect transport along MTs in vivo; these findings suggest a potential mechanism by which MAP4 could contribute to polarization or morphogenesis of cells. PMID- 9365276 TI - The location of the transport gate in the nuclear pore complex. AB - Signal-mediated nuclear transport is a gated process that occurs through a central transporter element located within the pore complex. The purpose of this investigation was to identify the region of the transporter that functions as the gate; i.e. the region that restricts passive diffusion of macromolecules through the pores. To accomplish this, small gold particles coated with polyethylene glycol (PEG; total particle diameter 40-70 A) or large PEG-particles (total diameter 110-270 A) were microinjected into the cytoplasm or nucleoplasm of Xenopus oocytes. Since PEG does not contain either nuclear import or export signals, it is assumed that the particles distribute by simple diffusion. The cells were fixed after 5 or 30 minutes and subsequently examined using TEM. The distribution of the particles located adjacent to and within the pore complexes was then mapped. The results obtained at both 5 and 30 minutes after cytoplasmic injections of small gold were basically the same. The particles readily entered the transporter but, on the average, were approximately 11 times more concentrated in the cytoplasmic half of this structure. The opposite distribution was observed following nuclear injections, i.e. the particles that were located in the transporter were approximately 7 times more numerous in the nuclear half. Our data indicate that there is a single transport gate located in the central domain of the transporter that restricts passive diffusion. The large particles that were injected into the cytoplasm migrated to the surface of the pore complex, but entered the transporter less frequently than small gold. Interestingly, the diffusion of large PEG-particles to the surface of the pores following nuclear injection was greatly restricted; however, this was not the case for similar size particles that were coated with protein containing nuclear export signals (NES). The latter results suggest that the NES is not only required for translocation, but also for migration within the nucleoplasm. PMID- 9365277 TI - Cytosolic phox proteins interact with and regulate the assembly of coronin in neutrophils. AB - The NADPH oxidase generates microbicidal superoxide in phagocytes, and when defective it leads to chronic granulomatous disease (CGD). Oxidase specific proteins in the cytosol, p47phox and p67phox, as well as the small GTP binding protein p21rac are important for activation of superoxide production. Because the activity of this oxidase is normally tightly restricted to the phagocytic vacuole, and its temporal and spatial organisation might be regulated by cytoskeletal proteins, we examined the cytosolic phox proteins for interactions with cytoskeletal elements. p67phox copurified with a 57 kDa protein, identified as coronin, an actin binding protein that is important for movement and phagocytosis in Dictyostelium. Binding studies revealed that coronin attaches to the C-terminal half of p40phox, a binding partner of p67phox. The phox proteins and coronin had a similar distribution in the cell, and both accumulated around the phagocytic vacuole. PMA activation of adherent neutrophils resulted in a major rearrangement of these proteins, and of actin, which were lost from the periphery of the cell and condensed around the nucleus. The rearrangement of F actin and coronin in adherent cells, were absent, or markedly diminished, in cells from patients lacking p47phox or p67phox in which an abnormally large proportion of the coronin was present as part of a large complex. The cytosolic phox proteins might play a regulatory role in the reorganisation of the cytoskeleton accompanying superoxide generation. PMID- 9365278 TI - A casein kinase I isoform is required for proper cell cycle progression in the fertilized mouse oocyte. AB - Casein kinase I is a family of serine/threonine protein kinases common to all eukaryotes. In yeast, casein kinase I homologues have been linked to the regulation of growth, DNA repair and cell division. In addition, their subcellular localization to membraneous structures and the nucleus is essential for function. In higher eukaryotes, there exist seven genetically distinct isoforms: (alpha), ss, (gamma)1, (gamma)2, (gamma)3, (delta) and (epsilon). Casein kinase I(alpha) exhibits a cell cycle-dependent subcellular localization including an association with cytosolic vesicular structures and the nucleus during interphase, and the spindle during mitosis. casein kinase I has also been shown to modulate critical regulators of growth and DNA synthesis/repair in mammalian cells such as SV40 large T antigen and p53. These results suggest that casein kinase I may be involved in processes similar to those ascribed to the yeast casein kinase I homologues. To define a role for casein kinase I(alpha) in cell cycle regulation, the mouse oocyte was utilized because of its well-defined cell cycle and ease of micromanipulation. Immunofluorescence studies from meiosis I of maturation to the first zygotic cleavage demonstrated that the kinase was associated with structures similar to those previously reported. Microinjection of casein kinase I(alpha) antibodies at metaphase II-arrest and G2 phase, had no effect on the completion of second meiosis or first division. However, microinjection of these antibodies during the early pronucleate phase prior to S phase onset blocked uptake of the kinase into pronuclei and interfered with proper and timely cell cycle progression to first cleavage. These results suggest that the kinase regulates the progression from interphase to mitosis during the first cell cycle. PMID- 9365279 TI - Rapid, microtubule-dependent fluctuations of the cell margin. AB - Using data automatically acquired by microinterferometry from large numbers of chick fibroblasts, we have detected rapid microfluctuations in the rates of protrusion and retraction of the cell margin which were strongly suppressed by colcemid, nocodazole and taxol. Fluctuations in the rate of retraction of the margin were about twice as powerful as fluctuations in the rate of protrusion. High-frequency fluctuations were also apparent in the cell track and in measures of cell spreading, shape and speed. These rapid fluctuations were also all suppressed by colcemid and nocodazole, sometimes by doses insufficient to disrupt the majority of microtubules. Taxol on the other hand did not suppress fluctuations in direction of the cell track nor fluctuations in the spreading of the cells but it was very effective at suppressing variations in protrusion and retraction and in cell speed and shape. We discovered that much slower, larger scale variations in protrusion, retraction, spreading, shape and speed resulted from the accumulation of these rapid, microtubule-dependent fluctuations of the cell margin. These large-scale variations in cell behaviour were also suppressed by the same drug treatments that were effective in suppressing the corresponding high-frequency fluctuations. We speculate that a function of microtubules is to enhance the fibroblast's responses to its environment by causing microfluctuations of the cell's margin which give rise to large-scale variations in cell behaviour. PMID- 9365280 TI - The Bacillus thuringiensis Cry1Ac toxin-induced permeability change in Manduca sexta midgut brush border membrane vesicles proceeds by more than one mechanism. AB - Aminopeptidase N purified from whole Manduca sexta midgut binds the Cry1Ac insecticidal toxin from Bacillus thuringiensis and this binding is inhibited by N acetylgalactosamine (GalNAc). We have examined the membrane permeabilising activity of the Cry1Ac toxin using brush border membrane vesicles (BBMV) prepared from the anterior (A-BBMV) and posterior (P-BBMV) subregions of the M. sexta midgut. A toxin mixing assay demonstrated a faster rate of toxin activity on P BBMV than on A-BBMV. In the presence of GalNAc this rapid activity on P-BBMV was reduced to the rate seen with A-BBMV. GalNAc had no effect on the rate of A-BBMV permeabilisation by Cry1Ac. Aminopeptidase N assays of A- and P-BBMV demonstrated that this Cry1Ac binding protein is concentrated in the posterior midgut region of M. sexta. It therefore appears that there are two mechanisms by which Cry1Ac permeabilises the M. sexta midgut membrane: a GalNAc-sensitive mechanism restricted to the posterior midgut region, probably involving aminopeptidase N binding, and a previously undetected mechanism found in both the posterior and anterior regions. PMID- 9365281 TI - Direct measurement of clathrin-coated vesicle formation using a cell-free assay. AB - Factors controlling the last stages of clathrin-coated vesicle formation were investigated using an assay allowing direct measurement of the detachment of these vesicles from the plasma membrane. Plasma membranes from cultured cells surface-labelled with 125I-alpha2-macroglobulin (a ligand that preferentially associates with clathrin-coated pits) were isolated by sonication of cells attached to a poly-L-lysine-coated substratum and incubated in the presence of nucleotide(s) +/- cytosol. A significant proportion of the membrane-associated radioactivity was released into the incubation medium in sedimentable form (14x10(6)g). The nucleotide and ligand specificities of this process together with the results of a series of biochemical, morphological and gradient analyses, led to the conclusion that measurement of the released sedimentable radioactivity provides a direct estimate of the formation of clathrin-coated vesicles from clathrin-coated pits. A morphological analysis of quick-frozen replicas of these membranes indicated that only the last stages of clathrin-coated vesicle formation were studied in the assay. Taking advantage of this cell-free system, we demonstrate that membrane-associated cytosolic factors and GTP-binding proteins, noteably dynamin, play a crucial role. Moreover, although these events can occur in the absence of ATP and Ca2+, optimal conditions for the formation of clathrin-coated vesicles require the presence of ATP, GTP and cytosol. PMID- 9365282 TI - The combination of epidermal growth factor and transforming growth factor-beta induces novel phenotypic changes in mouse liver stem cell lines. AB - Mouse liver stem cell (oval cell) lines were investigated in order to determine the role which two families of growth and differentiation factors (GDFs), epidermal growth factor (EGF) family and transforming growth factor beta (TGF beta) family, play in liver regeneration. EGF family members, including EGF, amphiregulin, betacellulin, heparin-binding epidermal growth factor, and TGF alpha, were mitogenic for oval cell lines while TGF-beta family members, including TGF-beta1, TGF-beta2 and TGF-beta3, inhibited mitogenesis and induced apoptosis in oval cell lines. Surprisingly, the combination of EGF family members and TGF-ss family members resulted in neither proliferation nor apoptosis but instead in a novel cellular response, cellular scattering in tissue culture and morphological differentiation in Matrigel. Analysis of the signal transduction pathways activated by exposure of oval cell lines to either EGF, EGF+TGF-beta, or TGF-beta indicated that novel combinations of intracellular signals result following stimulation of the cells with the combination of EGF+TGF-beta. These data reveal that the dynamics of synergistic GDF action following tissue injury and regeneration results in a new level of complexity not obvious from the study of individual GDFs. PMID- 9365283 TI - Occludin dephosphorylation in early development of Xenopus laevis. AB - Using immunoblot and immunofluorescence analysis with a cross-reacting antiserum, we identified Xenopus laevis occludin as a 57-61 kDa antigen colocalized with cingulin in epithelial junctions of embryos. Occludin was completely extracted from unfertilized eggs and embryos with a solution containing 0.1% Triton X-100 and 1% NP40. Maternal occludin in unfertilized eggs migrated by SDS-PAGE as a 61 kDa protein. In fertilized eggs and in early cleavages up to blastula stage 8 it migrated as a series of polypeptides with 57-60 kDa. In gastrulae, neurulae and tailbud stage embryos, it migrated as a 57 kDa polypeptide. The electrophoretic mobility downshift was specifically reproduced by treatment of extracts with acid phosphatase, indicating that it is due to dephosphorylation. The correlation of occludin dephosphorylation with the de novo assembly of tight junction in native epithelia of Xenopus embryos suggests a possible role of occludin dephosphorylation in the events leading to tight junction assembly. To identify kinases which can phosphorylate occludin, recombinant chicken occludin (cytoplasmic domain) was subjected to in vitro phosphorylation. Occludin was phosphorylated on serine and threonine residues by protein kinase CK2 and p34cdc2/cyclin B complex, but was not significantly phosphorylated by mitogen activated protein kinase, protein kinase CK1 and p38Syk tyrosine kinase. We noted that occludin sequences contain a motif matching the activation loop of the cytoplasmic domain of insulin receptor kinase. PMID- 9365284 TI - Passive smoking: history repeats itself. PMID- 9365285 TI - High cost, low volume care: the case of haemophilia. PMID- 9365286 TI - Formula fever: allocating resources in the NHS. PMID- 9365287 TI - Ethics and international research. PMID- 9365288 TI - Hastening slowly: Mr Dobson plays a waiting game. PMID- 9365290 TI - US flight attendants win settlement over passive smoking. PMID- 9365291 TI - Hong Kong issues guidelines to prevent further medical blunders. PMID- 9365292 TI - Conflict over South African attempts to cut drug costs. PMID- 9365293 TI - The prion hypothesis is finally accepted by the establishment. PMID- 9365294 TI - Environmental tobacco smoke exposure and ischaemic heart disease: an evaluation of the evidence. AB - OBJECTIVES: To estimate the risk of ischaemic heart disease caused by exposure to environmental tobacco smoke and to explain why the associated excess risk is almost half that of smoking 20 cigarettes per day when the exposure is only about 1% that of smoking. DESIGN: Meta-analysis of all 19 acceptable published studies of risk of ischaemic heart disease in lifelong non-smokers who live with a smoker and in those who live with a non-smoker, five large prospective studies of smoking and ischaemic heart disease, and studies of platelet aggregation and studies of diet according to exposure to tobacco smoke. RESULTS: The relative risk of ischaemic heart disease associated with exposure to environmental tobacco smoke was 1.30 (95% confidence interval 1.22 to 1.38) at age 65. At the same age the estimated relative risk associated with smoking one cigarette per day was similar (1.39 (1.18 to 1.64)), while for 20 per day it was 1.78 (1.31 to 2.44). Two separate analyses indicated that non-smokers who live with smokers eat a diet that places them at a 6% higher risk of ischaemic heart disease, so the direct effect of environmental tobacco smoke is to increase risk by 23% (14% to 33%), since 1.30/1.06 = 1.23. Platelet aggregation provides a plausible and quantitatively consistent mechanism for the low dose effect. The increase in platelet aggregation produced experimentally by exposure to environmental tobacco smoke would be expected to have acute effects increasing the risk of ischaemic heart disease by 34%. CONCLUSION: Breathing other people's smoke is an important and avoidable cause of ischaemic heart disease, increasing a person's risk by a quarter. PMID- 9365295 TI - The accumulated evidence on lung cancer and environmental tobacco smoke. AB - OBJECTIVE: To estimate the risk of lung cancer in lifelong non-smokers exposed to environmental tobacco smoke. DESIGN: Analysis of 37 published epidemiological studies of the risk of lung cancer (4626 cases) in non-smokers who did and did not live with a smoker. The risk estimate was compared with that from linear extrapolation of the risk in smokers using seven studies of biochemical markers of tobacco smoke intake. MAIN OUTCOME MEASURE: Relative risk of lung cancer in lifelong non-smokers according to whether the spouse currently smoked or had never smoked. RESULTS: The excess risk of lung cancer was 24% (95% confidence interval 13% to 36%) in non-smokers who lived with a smoker (P < 0.001). Adjustment for the effects of bias (positive and negative) and dietary confounding had little overall effect; the adjusted excess risk was 26% (7% to 47%). The dose-response relation of the risk of lung cancer with both the number of cigarettes smoked by the spouse and the duration of exposure was significant. The excess risk derived by linear extrapolation from that in smokers was 19%, similar to the direct estimate of 26%. CONCLUSION: The epidemiological and biochemical evidence on exposure to environmental tobacco smoke, with the supporting evidence of tobacco specific carcinogens in the blood and urine of non smokers exposed to environmental tobacco smoke, provides compelling confirmation that breathing other people's tobacco smoke is a cause of lung cancer. PMID- 9365296 TI - Prevalence of carcinoma in situ of the testis in 207 oligozoospermic men from infertile couples: prospective study of testicular biopsies. AB - OBJECTIVE: To investigate the prevalence of carcinoma in situ of the testis in a group of oligozoospermic men from infertile couples. DESIGN: A consecutive group of oligozoospermic men from infertile couples were offered bilateral testicular biopsy. The observed prevalence of carcinoma in situ was compared with the expected prevalence of testicular cancer in a corresponding age matched population of Danish men, assuming all untreated cases of carcinoma in situ progress to tumour stage. This calculation was based on data from the Danish Cancer Registry. SUBJECTS: 207 men aged 18-50 years who had sperm density below 10 million/ml in two samples within the previous 2 years or sperm density below 20 million/ml in two samples within the previous 2 years and a history of cryptorchidism or one or two atrophic testicles (orchidometer volume less than 15 cm3), or both. INTERVENTIONS: Bilateral testicular biopsies. MAIN OUTCOME MEASURES: Carcinoma in situ in the biopsy specimen. RESULTS: No case of carcinoma in situ was found among the 207 men. The expected number in a normal age matched population of corresponding size was 0.8. CONCLUSIONS: There is no increase in risk of carcinoma in situ of the testis in moderately oligozoospermic men of couples referred because of infertility. PMID- 9365298 TI - Comparison of case fatality in smokers and non-smokers after acute cardiac event. PMID- 9365297 TI - Comparison of two assays for measuring plasma concentrations of paracetamol. PMID- 9365300 TI - Science, medicine, and the future. Obesity treatment. PMID- 9365299 TI - Sociodemographic and morbidity indicators of need in relation to the use of community health services: observational study. AB - OBJECTIVE: To examine whether the sociodemographic and morbidity characteristics of populations influence their use of the following community heath services: district nursing, health visiting, chiropody, community maternity, community mental illness, and the professions allied to medicine. DESIGN: Observational study. SETTING: Nationally representative sample of provider trusts in England. MAIN OUTCOME MEASURES: Activity levels for each service calculated for enumeration districts within the catchment areas of the sample of trusts and standardised to allow for differences in age structure. Regression analysis to determine whether the standardised activity rates for each service could be predicted by a range of socio-demographic and morbidity proxies. RESULTS: Morbidity or deprivation, or both, seemed to influence the use of services in each of the care programmes examined. CONCLUSIONS: The allocation of funds for community health services should allow for differences in the health and socio demographic characteristics of health authorities. PMID- 9365301 TI - Subjective change in ejaculate as symptom of infection with Schistosoma haematobium in travellers. PMID- 9365302 TI - ABC of palliative care. Mouth care, skin care, and lymphoedema. PMID- 9365303 TI - As the health divide widens in Sweden and Britain, what's happening to access to care? PMID- 9365304 TI - Personal paper: the conflict in transferring a cystic fibrosis specialist service between two hospitals in Manchester. PMID- 9365305 TI - Trends in asthma mortality. Data on seasonality of deaths due to asthma were omitted from paper but editorial's author did not know. PMID- 9365306 TI - Trends in asthma mortality. Asthma mortality in United States has risen but is similar to that in England and Wales. PMID- 9365307 TI - Trends in asthma mortality. Death certification in asthma is inaccurate. PMID- 9365308 TI - Trends in asthma mortality. Short-term fluctuations may obscure more meaningful, longer term, changes. PMID- 9365309 TI - Trends in asthma mortality. Asthma mortality is falling in most age groups in Scotland. PMID- 9365310 TI - Trend in occurrence of asthma among children and young adults. Reporting of common respiratory and atopic symptoms has increased. PMID- 9365311 TI - Trend in occurrence of asthma among children and young adults. Labelling of cough alone as asthma may partially explain increase. PMID- 9365312 TI - Helicobacter gastroduodenitis. Routine treatment will lead to extra workload. PMID- 9365313 TI - Adding heat probe treatment to adrenaline injection for spurting haemorrhage of peptic ulcers. Injection of adrenaline and human thrombin is best option. PMID- 9365314 TI - "Clearing house" is needed to match available junior doctors to unfilled SHO posts. PMID- 9365315 TI - Debate over mentally ill patient's caesarean section was too emotional. PMID- 9365316 TI - Insulin dependent diabetes is probably due to environmental effect during childhood. PMID- 9365317 TI - Palliative drugs are not for shortening life. PMID- 9365318 TI - Frequent consumption of red meat is not risk factor for cancer. PMID- 9365319 TI - Incidence of early syphilis acquired in former Soviet Union is increasing. PMID- 9365320 TI - Stroke prevention in atrial fibrillation. Suggested range of international normalised ratio may lead to overanticoagulation. PMID- 9365321 TI - Elimination of firearms. All guns should be banned from homes. PMID- 9365322 TI - Elimination of firearms. Author gave underestimate of deaths due to firearms. PMID- 9365323 TI - Medical advice is available for ships at sea. PMID- 9365324 TI - Defence of cardiologist in misconduct case. Union defence should not always apply. PMID- 9365325 TI - Defence of cardiologist in misconduct case. Members of Medical Defence Union are entitled to help with defamation cases. PMID- 9365326 TI - Delayed diagnosis for breast disease is mostly due to patients. PMID- 9365327 TI - Helicobacter pylori infection in children with abdominal ailments in a developing country. AB - Helicobacter pylori commonly infects children in developing countries. To determine the frequency of this infection and its potential role in specific gastrointestinal entities, all patients requiring upper gastrointestinal endoscopy for the evaluation of abdominal ailments in a gastroenterology practice in Lima, Peru, were evaluated during a 1-year period. Gastric biopsies were obtained for each child and were stained with hematoxylin-eosin and Warthin Starry stains. Of the 107 evaluable patients (mean age 7.4 years, 58% boys), 52 (49%) were infected. The infection rate increased with older patients (P = 0.004). Children with recurrent abdominal pain (P = 0.04), an endoscopic finding of nodular gastritis (P = 0.007), and a histologic finding of chronic active gastritis (P < 0.0001) were infected more commonly. PMID- 9365328 TI - Gastric distention exacerbates ischemia in a rodent model of partial gastric devascularization. AB - Occult ischemia of the mobilized gastric fundus is an important etiologic factor for esophagogastric anastomotic leaks after esophagectomy. Postoperative gastric distention is another possible predisposing factor for anastomotic leakage. We hypothesized that gastric distention could worsen gastric ischemia. To test this hypothesis, gastric tissue perfusion was studied in 20 Sprague-Dawley rats. Baseline serosal gastric tissue perfusion was measured by laser-Doppler flowmetry at a point 10 mm distal to the gastroesophageal junction. Perfusion was measured after left gastric artery occlusion, gastric distention to 20 cm water pressure, and combined left gastric artery occlusion and gastric distention. Gastric tissue perfusion (in tissue perfusion units, TPU) was 64.2 +/- 9.1 TPU at baseline measurement, 18.6 +/- 4.3 TPU after left gastric artery occlusion, 22.0 +/- 4.1 TPU after gastric distention, and 7.8 +/- 1.8 TPU after combined left gastric artery occlusion and gastric distention. Distention (P < 0.0001) and arterial occlusion (P < 0.0001) both reduced gastric tissue perfusion; of the two, arterial occlusion produced the greatest reduction in perfusion (P < 0.021). The combination of distention and arterial occlusion caused greater reduction in gastric perfusion than either factor alone (P < 0.0001). In this model, gastric distention exacerbated the ischemia produced by partial gastric devascularization. In clinical esophageal surgery, postoperative gastric distention may similarly potentiate the ischemic effects of gastric transposition for esophageal reconstruction. PMID- 9365329 TI - Incidental pituitary macroadenoma: a population-based study. AB - Epidemiologic analysis of incidental macroadenoma is limited to autopsy studies and case series. There are no published data about prevalence of incidental pituitary macroadenoma in living patients. The objective of this study was to determine the prevalence of incidental pituitary macroadenoma. It was designed as an observational study of cranial computed tomography reports. An urban department of veterans affairs medical center was used for the setting. The subject group consisted of 3,550 consecutive patients at the Cleveland Department of Veterans Affairs Medical Center from January 1993 to January 1996. Patients with known or suspected pituitary or parasellar disease were excluded. Cranial computed tomography reports were reviewed. Original films and medical charts of all patients with pituitary macroadenoma were reviewed. Seven patients with incidentally discovered pituitary macroadenoma that ranged from 1 cm to 2.5 cm were found; prevalence was 0.20% (95% confidence interval 0.05, 0.35%). Evidence of partial hypopituitarism was found in most patients. All patients had normal visual fields at initial examination despite the size of the tumor, but 1 of 4 had a field cut demonstrated by Goldmann perimetry. These data confirm that, although the prevalence of incidental pituitary macroadenoma is low, screening identified patients to detect deficiency of corticotropin, thyroid-stimulating hormone, and gonadotropins and to detect visual field defects is important. PMID- 9365330 TI - Nephrotoxicity of high-dose ifosfamide/carboplatin/etoposide in adults undergoing autologous stem cell transplantation. AB - The objective of this study was to evaluate nephrotoxicity in adult patients treated with high-dose ifosfamide, carboplatin, and etoposide followed by autologous stem cell transplantation. We conducted a retrospective analysis of clinical and laboratory data from 131 patients with various malignancies who received treatment with escalating doses of ifosfamide, carboplatin, and etoposide followed by autologous stem cell transplantation as part of a phase I/II therapeutic trial. Abnormalities in glomerular filtration were evaluated by measuring peak creatinine levels and tubular dysfunction by the lowest recorded serum levels of potassium, magnesium, and bicarbonate, at different time periods after administration of ifosfamide, carboplatin, and etoposide, and after autologous stem cell transplantation. For the entire group of 131 patients, peak creatinine levels were > 1.5 mg/dL but < 3.0 mg/dL in 37% and levels were > 3.0 mg/dL in 11% at some time during their hospital stay. At the time of discharge, creatinine levels were 1.6 mg/dL to 3.0 mg/dL in 25% of patients and were > 3 mg/dL in 5%. Immediately after high-dose therapy, peak creatinine levels were significantly higher in patients receiving higher doses of ifosfamide compared to those receiving lower doses (P < 0.00001) and those receiving intermediate doses (P < 0.005). There was a dramatic decrease in serum bicarbonate, potassium, and magnesium levels immediately after chemotherapy, and they remained significantly decreased throughout the patient's hospital stay, despite massive replacement efforts (P ranging between < 0.008 and < 0.001). This is the largest adult population study documenting the incidence and severity of ifosfamide/carboplatin/etoposide-associated acute nephrotoxicity. Renal dysfunction was dose related and reversible in the majority of patients. PMID- 9365331 TI - The peripheral intravenous cannula: a cause of venous air embolism. AB - Venous air embolism has been reported as a complication of invasive diagnostic and therapeutic procedures or accidental trauma. Little is known about the incidence of air embolism after minimal intravenous manipulations, such as the insertion of a peripheral intravenous cannula. Small air emboli in the central veins, central arteries, and cardiac chambers can be detected during electron beam computed tomography studies of the chest. Electron-beam computed tomography of the chest was performed on 208 patients after the insertion of a peripheral intravenous cannula. The images were analyzed using a digital workstation. Small air embolism was visible in 10 of 208 (4.8%) patients in the following locations: the pulmonary trunk in 6 patients, the right ventricle in 2, the right atrium in 1, and the left brachiocephalic vein in 1. The embolism was asymptomatic in each patient. Although the potential risks in patients with septal defects and shunts remain unclear, caution should be taken with minimal intravenous manipulations. PMID- 9365332 TI - Inhibition of low-density lipoprotein oxidation by oral herbal mixtures Maharishi Amrit Kalash-4 and Maharishi Amrit Kalash-5 in hyperlipidemic patients. AB - Low-density lipoprotein (LDL) oxidation is central to the pathogenesis of atherosclerosis. We have shown previously that the herbal mixtures Maharishi Amrit Kalash-4 (MAK-4) and Maharishi Amrit Kalash-5 (MAK-5) inhibit LDL oxidation induced by cupric ions (Cu+2) and endothelial cells in vitro and that MAK-4 reduces atherosclerosis in Watanabe heritable hyperlipidemic rabbits that were fed this herbal mixture. This study evaluates the antioxidant activity of MAK-4 and MAK-5 in vivo. Ten hyperlipidemic patients prescribed stable hypolipidemic therapy were treated with MAK-4 and MAK-5 for 18 weeks. Plasma lipoprotein, plasma lipid peroxide, and LDL oxidation studies were performed every 6 weeks. Apolipoprotein A, apolipoprotein B, and lipoprotein (a) levels were measured at baseline and 18 weeks. After 12 weeks of treatment with MAK-4 and MAK-5, a time dependent increase in the lag phase and delay in the propagation phase of oxidation of LDL by Cu+2 and endothelial cells was seen. Lag phases at baseline and after 6, 12, and 18 weeks of MAK-4 and MAK-5 ingestion were 6.66 hours +/- 0.19 (mean +/- standard error of mean), 6.77 hours +/- 0.31, 7.22 hours +/- 0.24, and 18.00 hours +/- 0.73, respectively, for Cu(+2)-catalyzed LDL oxidation. Lag phases were 14.89 hours +/- 0.77, 13.33 hours +/- 0.50, 20.22 hours +/- 0.76, and 20.00 hours +/- 0.79, respectively, for endothelial cell-induced LDL oxidation. The levels of plasma lipid peroxide did not change significantly. No significant changes were seen in the plasma lipoproteins and the levels of apolipoprotein A, apolipoprotein B, and lipoprotein (a). The results show that MAK-4 and MAK-5 inhibit LDL oxidation in patients with hyperlipidemia. Therefore, MAK-4 and MAK-5 may be useful in the prevention and treatment of atherosclerosis. PMID- 9365333 TI - Signal transduction: activation of the guanylate cyclase-cyclic guanosine-3'-5' monophosphate system by hormones and free radicals. AB - Intracellular communication and transmission of messages for many hormones and free radicals occur after the hormones and free radicals bind to their receptors by enhancing the activity of guanylate cyclase, the enzyme that catalyzes the conversion of guanosine triphosphate to the intracellular messenger cyclic guanosine-3'-5' monophosphate (cyclic GMP). The guanylate cyclase-linked receptors exist intracellularly (ie, cytoplasmic) and in membrane-bound forms. Enhancement of guanylate cyclase by hormones or free radicals increases intracellular cyclic GMP, which closes cation channels in the kidney while activating cation channels in the retina and olfactory cilia, either directly or by cyclic GMP-dependent protein kinase. Cyclic GMP also has potent blood pressure lowering properties. Cyclic GMP promotes growth by increasing DNA, RNA, and protein synthesis. Overactivity of this system is observed in Traveler's diarrhea, whereas underactivity occurs in Chediak-Higashi syndrome in which lysosomal enzyme release and chemotaxis are defective and can be corrected in vitro by addition of cyclic GMP. PMID- 9365334 TI - Hypertrophic cardiomyopathy: presentation and pathophysiology. AB - HCM is a heterogeneous disease with various clinical presentations. Recent advances in understanding the genetic abnormalities responsible for ventricular hypertrophy promise to improve our ability to diagnose this condition and to identify subgroups who are at the highest risk of cardiovascular mortality. Numerous difficulties remain in treating patients with HCM, including obtaining relief of symptoms and preventing SCD, but several new treatment options are currently being evaluated. In the future, randomized trials comparing the major treatment options (eg, pharmacologic therapy, myotomy/myectomy, mitral valve replacement, pacemaker implantation, and nonsurgical septal reduction) will be needed to provide guidance concerning the optimal treatment of patients with HCM. PMID- 9365335 TI - Mouth and genital ulcers with inflamed cartilage (MAGIC syndrome): a case report and literature review. AB - A 39-year-old woman had relapsing polychondritis and Behcet's disease, which was described as mouth and genital ulcers with inflamed cartilage syndrome (MAGIC). Serologic human leukocyte antigen analysis showed A24 (9), A31 (19), B56 (22), B62 (15), Cw6, DR4, DR9. Human leukocyte antigen allele analysis revealed DRB1* 0406/0901, DQA1* 0301/0301, DQB1* 0302/0303, DPB1* 0201/0501 through determining the genotype using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Treatment with methotrexate (5 mg/week) and pentoxifylline (300 mg/d) was effective to control oral ulcers, erythema nodosum, and arthritis. PMID- 9365336 TI - Unusual presentations of hypothyroidism. AB - Hypothyroidism is a commonly diagnosed endocrine disorder. Typical signs and symptoms of hypothyroidism include lethargy, cold intolerance, hoarseness, dry skin, constipation, delayed relaxation phase of deep tendon reflexes, and bradycardia. Hypothyroidism, presenting with such classic manifestations, usually is readily recognized and, therefore, easy to diagnose. Occasionally patients have less commonly emphasized symptoms, making the diagnosis less apparent. Such atypical presentations may suggest other diseases as the primary problem and, therefore, the initial focus of attention is on a diagnosis other than hypothyroidism. We have observed patients with hypothyroidism with rare manifestations. The diagnosis of primary hypothyroidism was established in all patients by thyroid function tests, and initiation of thyroid hormone therapy resulted in significant improvement of the presenting symptom. We considered it instructive to report about these patients because it shows the need to be aware of the unusual presentations of hypothyroidism and to consider hypothyroidism when confronted with atypical clinical manifestations. PMID- 9365337 TI - Adrenal myelolipoma associated with endocrine dysfunction: review of the literature. AB - A case of bilateral adrenal myelolipoma in association with congenital adrenal hyperplasia caused by 21-hydroxylase deficiency is presented. The clinical, radiologic, and endocrinologic features of this case are correlated with a review of the literature. PMID- 9365338 TI - Acute myocardial infarction with normal coronary artery: a case report and review of literature. AB - A 17-year-old girl with no risk factors for coronary artery disease had acute myocardial infarction. She received thrombolytic therapy with tissue-type plasminogen activator. An extensive workup for the cause of myocardial infarction revealed protein S deficiency. Angiography showed normal coronary arteries. We speculate that the cause of myocardial infarction was coronary spasm or thrombus formation, which was successfully dissolved by thrombolytic therapy. This is the eighth case report of acute myocardial infarction in a patient with normal coronaries and protein S deficiency. We reviewed the literature concerning myocardial infarction and normal coronaries and protein S deficiency. This case report and review of the literature suggest the need to extend the concept of classic risk factors for coronary artery disease in young patients with myocardial infarction and normal coronary arteries. PMID- 9365339 TI - Sarcoidosis presenting as unilateral alveolar consolidation. AB - Sarcoidosis is a multisystem granulomatous disorder that has variable clinical and radiologic manifestations. We describe a rare case of a 35-year-old black woman who had a nonresolving focal alveolar infiltrate. Her symptoms did not improve with the administration of antibiotics, and a more extensive workup, including fiberoptic bronchoscopy with transbronchial biopsy and a conjunctival biopsy showed noncaseating granulomata. We conclude that sarcoidosis should be included in the differential diagnosis of nonresolving alveolar opacity in populations that have increased incidence. PMID- 9365340 TI - Ritual relieved axial dystonia triggered by gaze-evoked amaurosis. AB - A woman with chronic posttraumatic axial lateropulsion cervical dystonia ("belly dancer's head") found relief of her spontaneous dystonic spasms by the sequential performance of an elaborate motor ritual. During an episode of left optic papillitis caused by central retinal vein occlusion, gaze-evoked amaurosis of the left eye developed, preceded by achromatopsia, during left lateral gaze. Gaze evoked amaurosis triggered axial dystonia, which was followed by her unique, stereotyped, dystonia-relieving ritual that simulated a slow dance. Visual symptoms improved progressively in 1 year. Eventually, she was unable to trigger her dystonia by eye movements. Spontaneous dystonia remained otherwise unchanged from before the episode of papillitis and was still relieved by her unique ritual. PMID- 9365341 TI - Heparin therapy for myocardial infarction: an unusual trigger for pituitary apoplexy. AB - A 68-year-old man with coronary artery disease was admitted for chest pain and ventricular tachycardia. After electric cardioversion, therapeutic heparinization was started for myocardial ischemia and nontransmural infarction. On day 3, headache and fever developed, followed by an altered sensorium and hyponatremia. Infectious etiology for the fever was excluded, and results of computed tomography of the brain were normal. Later magnetic resonance imaging (Day 10) demonstrated a pituitary macroadenoma with hemorrhage. Treatment for panhypopituitarism with stress-dose steroids stabilized the patient, and the fever and hyponatremia resolved. Transsphenoidal resection of the pituitary adenoma was performed without incident. This is the first reported case of pituitary apoplexy after heparin anticoagulation for acute myocardial infarction, although chronic anticoagulation in other settings has been reported as a precipitant of apoplexy. The uncommon presentation of a "central" fever and confusion in a patient with previously undiagnosed adenoma posed a diagnostic challenge. Subtle presentations of panhypopituitarism, knowledge of which should lead to suspicion and early diagnosis of pituitary apoplexy, will prevent anticoagulant-induced central nervous system catastrophes and potential fatalities. PMID- 9365342 TI - Emphysematous pyelonephritis in a nonfunctioning renal allograft of a patient undergoing hemodialysis. AB - A hemodialysis patient with insulin-dependent diabetes mellitus and a non functioning renal allograft in whom fever, low blood pressure, and confusion developed is reported. She underwent extensive evaluation and allograft nephrectomy for emphysematous pyelonephritis that was diagnosed by the presence of air in the collecting system of the transplanted kidney during computerized tomography of the abdomen. In nine patients with emphysematous pyelonephritis in renal allografts reported previously, this is the first instance of emphysematous pyelonephritis in a renal allograft with coagulase-negative staphylococcus. PMID- 9365343 TI - Recovery of ambulation in motor-incomplete tetraplegia. AB - OBJECTIVE: To determine the effect of age and initial neurologic status on recovery of ambulation in patients with motor-incomplete tetraplegia. STUDY DESIGN: Inception cohort study. SETTING: Urban, tertiary care hospital with Regional Spinal Cord Injury Center. PATIENTS: One hundred five patients with American Spinal Injury Association (ASIA) C or D tetraplegia at admission or within 72 hours of injury. MAIN OUTCOME MEASURE: Ambulatory status at time of discharge from inpatient rehabilitation. RESULTS: Ninety-one percent (30/33) of ASIA C patients younger than 50 years of age became ambulatory by discharge, versus 42% (13/31) ASIA C patients age 50 or older (p < .0001). All (41/41) patients initially classified as ASIA D became ambulatory by discharge. CONCLUSION: For patients with ASIA D tetraplegia, prognosis for recovery of independent ambulation is excellent. For patients with ASIA C tetraplegia, recovery of ambulation is significantly less likely if age is 50 years or older. PMID- 9365344 TI - Lipid, lipoprotein, and apolipoprotein profiles in active and sedentary men with tetraplegia. AB - OBJECTIVE: To investigate whether the risk profile of coronary heart disease (CHD) is more favorable in physically active men with tetraplegia compared with sedentary men with tetraplegia. DESIGN: Using a cross-sectional design, the lipid and (apo)lipoprotein concentrations of 11 active and 13 sedentary men with tetraplegia were compared. Regression analysis was applied to investigate the influence of subject characteristics and behavioral factors on the risk profile of CHD. MAIN OUTCOME MEASURES: Total plasma cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides, apolipoprotein-A1 (ApoA1), and apolipoprotein-B (ApoB) concentrations were determined. Low-density lipoprotein cholesterol (LDL-C) and the ratios TC/HDL-C, LDL-C/HDL-C, ApoA1/ApoB, and HDL C/ApoA1 were calculated. RESULTS: A significantly higher HDL-C and ApoA1/ApoB and lower TC/HDL-C were found in the active group. Age and body mass index were important determinants of the lipids and (apo)lipoproteins. Sport activity was the only significant determinant of HDL-C. CONCLUSIONS: Results suggest a positive influence of sport activity on HDL-C in men with tetraplegia, which may reduce the risk of CHD. PMID- 9365345 TI - Clinical experience with paraspinal mapping. I: Neurophysiology of the paraspinal muscles in various spinal disorders. AB - OBJECTIVE: To assess the extent of denervation of the paraspinal muscles in spinal disorders. DESIGN: Nonrandomized prospective trial. SETTING: Electrodiagnostic laboratory of a university spine center and of a private practice in a small community. SUBJECTS: One hundred fourteen consecutive persons referred for electrodiagnosis of spinal or lower extremity disorders. INTERVENTION: The paraspinal mapping (PM) electromyography (EMG) protocol along with codified history, physical examination, extremity EMG, and in 44 cases, radiologic imaging results. MAIN OUTCOME MEASURES: PM scores compared with recently established norms (95% of normal subjects scoring less than < 6), lower extremity (LE) EMG findings, and imaging results. RESULTS: Fifty-eight subjects had normal PM scores; 62 were abnormal. Compared to imaging studies, false positive rate was 8% (1/13). False negative rate (normal PM with definite nerve involvement on imaging) was 33% (6/18), but this decreased to 5% when PM was combined with LE EMG. Four of 4 high lumbar lesions were detected by PM. Of 14 apparent false negatives (13%) compared to LE EMG, 6 had S1 root lesions and 5 had nonspinal lesions. All 7 subjects with isolated S1 radiculopathy had PM scores within normal limits. Occasional polyneuropathies presented with normal PM and abnormal distal findings or with abnormal PM but normal distal findings. No patient with isolated paraspinal findings had evidence of malignancy on follow up. This report also describes the distribution of denervation in the multifidus, longissimus, and iliocostalis in various disorders. CONCLUSIONS: PM related well to imaging studies and LE EMG. It detects uncommon high lumbar root lesions. S1 may not innervate the paraspinal muscles. There are isolated paraspinal findings in persons without malignancy. The effects of specific muscle denervation on biomechanics, rehabilitation exercise, and prognosis are not known. PMID- 9365346 TI - Clinical experience with paraspinal mapping. II: A simplified technique that eliminates three-fourths of needle insertions. AB - OBJECTIVE: To simplify and minimize the quantified needle examination of the paraspinal muscles (paraspinal mapping [PM]) without compromising sensitivity or specificity. DESIGN: Nonrandomized prospective trial. SETTING: Electrodiagnostic laboratory of a university spine center and of a private practice in a small community. SUBJECTS: One hundred fourteen consecutive persons referred for electrodiagnosis of spinal or lower extremity disorders who had PM data and 35 previously reported asymptomatic volunteers. INTERVENTION: Abbreviated PM protocols were simulated by progressively eliminating data from the 45 needle insertions of the original PM. Simulations involving 35, 15, 13, and 5 insertions resulted in different normal values (95% of asymptomatic volunteers) and different scores in patients. The resulting reclassification of patients as normal or abnormal was compared with the original protocol and with clinical data. MAIN OUTCOME MEASURES: False positive and false negative rates of the simulations compared with the original protocol. RESULTS: Abbreviated protocols involving 30, 15, 13, and 5 needle insertions had normal cutoff scores of less than 5, less than 4, less than 3, and less than 2, respectively, with 2%, 2%, 4%, and 8% false positive rates and 3%, 8%, 13%, and 21% false negative rates compared with the original. In many cases clinical information correlated better with the abbreviated test results than the original PM. CONCLUSIONS: The third protocol compared well with the original PM, and in a limited number of patients with imaging studies demonstrated 92% sensitivity and 92% specificity. By eliminating the iliocostalis, longissimus, and lowest multifidus needle explorations, 73% fewer needle insertions were used. We recommend that this new technique, now called "miniPM," be used in most clinical settings. PMID- 9365347 TI - Reversal of antagonists: effect of elbow extension strength and endurance. AB - OBJECTIVE: To evaluate the reversal of elbow antagonists designed to facilitate the extensors relative to agonist-only contractions of the extensors, while using a protocol previously demonstrated to result in an increase in strength through motor learning. DESIGN: Two-group convenience sample composed of healthy subjects. SETTING: Clinic research laboratory. SUBJECTS: Twenty-eight healthy women without a history of upper extremity injury or neurologic disorder. MEASUREMENTS: Elbow extension strength and endurance were measured during maximal effort isometric reversal of the elbow antagonists (experimental group) and elbow extension only (control group) resistance exercise. Biceps brachii short head (BBS), triceps brachii lateral head (TLAT), and triceps brachii long head (TLNG) electromyographic (EMG) activity was measured concurrently. RESULTS: There were no significant differences between groups for either elbow extension strength, BBS, TLAT, or TLNG EMG activity. The experimental and control groups exhibited a significant linear (p < .01) and quadratic (p < .01) increase in baseline strength of 5.2N.m (30.5%). EMG activity from each muscle group increased linearly (p < .01) across all test sessions. Similar results were observed for elbow extension strength and biceps and triceps EMG activity during fatigue testing. CONCLUSIONS: The reversal of antagonists technique was not superior to agonist-only resistance exercise, nor did it interfere with the acquisition of muscular strength or endurance through motor learning. PMID- 9365348 TI - Local heat effect on sympathetic skin responses after pain of electrical stimulus. AB - OBJECTIVE: To investigate the analgesic effort of local superficial heating by studying sympathetic skin responses. DESIGN: Randomized trial. SETTING: Electromyography laboratory in the department of physical therapy and rehabilitation of a university hospital. SUBJECTS: Twenty healthy volunteers participated with informed consent. INTERVENTIONS: Sympathetic skin response (SSR) amplitudes following electrical stimulation of the right peroneal nerve and skin temperatures in both hands were recorded simultaneously. All of the recordings were repeated at 5-minute intervals during local heat application over the right palm and within 15 minutes after heat application was stopped. RESULTS: SSR amplitudes in both hands decreased significantly during local heating (p < .05) and did not return to their initial levels within 15 minutes of the recovery period; the reductions remained statistically significant (p < .05). Amplitude reductions were statistically more significant on the heated hand compared with those on the contralateral hand (p < .05). CONCLUSION: Therapeutic local heat application reduces the sudomotor response to a painful stimulus. This analgesic effect may be due to suppression of cortical pain sensation resulting from increased levels of endorphins, and may also be a result of local inhibition of both afferent and efferent C fibres. PMID- 9365349 TI - Response of pain to static magnetic fields in postpolio patients: a double-blind pilot study. AB - OBJECTIVE: To determine if the chronic pain frequently presented by postpolio patients can be relieved by application of magnetic fields applied directly over an identified pain trigger point. DESIGN: Double-blind randomized clinical trial. SETTING: The postpolio clinic of a large rehabilitation hospital. PATIENTS: Fifty patients with diagnosed postpolio syndrome who reported muscular or arthritic like pain. INTERVENTION: Application of active or placebo 300 to 500 Gauss magnetic devices to the affected area for 45 minutes. MAIN OUTCOME MEASURE: Score on the McGill Pain Questionnaire. RESULTS: Patients who received the active device experienced an average pain score decrease of 4.4 +/- 3.1 (p < .0001) on a 10-point scale. Those with the placebo devices experienced a decrease of 1.1 +/- 1.6 points (p < .005). The proportion of patients in the active-device group who reported a pain score decrease greater than the average placebo effect was 76%, compared with 19% in the placebo-device group (p < .0001). CONCLUSIONS: The application of a device delivering static magnetic fields of 300 to 500 Gauss over a pain trigger point results in significant and prompt relief of pain in postpolio subjects. PMID- 9365350 TI - Kinematics of the elbow during wheelchair propulsion: a comparison of two wheelchairs and two stroking techniques. AB - OBJECTIVE: The kinematics of the elbow joint were studied for two types of wheelchairs and during two types of propulsive strokes. PARTICIPANTS: Ten serially selected healthy volunteers propelled a standard and a lightweight wheelchair on a roller system with both circular and pumping strokes. DESIGN: Kinematic data for the wheelchair and the upper extremity were collected by an optical tracking system. These kinematic descriptors were subsequently time normalized with a spline algorithm to provide a graphic description of the wheelchair strokes. MAIN OUTCOME MEASURES: Thirteen discrete variables were compared for the two chairs and the two propulsive strokes. RESULTS: Total elbow motion ranged from 60.9 degrees of flexion to 5.2 degrees of extension. Maximal elbow flexion velocity ranged from 515.4 degrees to 572.8 degrees per second. Kinematic differences between the two wheelchairs were minimal, with a trend for 8.3 degrees to 5.2 degrees more elbow flexion in the lightweight wheelchair (p < .05), depending on the stroke used. With the use of any one chair, the style of the stroke had no significant effect on elbow kinematics, but the use of a pumping stroke did decrease propulsion arc by 12 degrees to 14 degrees (p < .05). CONCLUSION: No major differences regarding elbow kinematics were seen between the two types of wheelchairs. The pumping-stroke technique resulted in a shortened handrim contact arc. PMID- 9365351 TI - Facet tropism in lumbar motion segments and its significance in disc herniation. AB - OBJECTIVE AND DESIGN: To define facet tropism (FT) for each motion segment of the lower lumbar spine for subjects without disc herniation, and to evaluate the significance of facet tropism in disc herniation. METHODS: Sixty subjects were evaluated by measuring the facet angle (FA) of three lower lumbar motion segments with the use of computed tomography (CT) and a computer program. The subjects were divided into two groups: 33 without disc herniation and 27 with disc herniation at one or more levels of lower lumbar motion segments. The FA was defined as the angle of the facet and midsagittal lines. The difference between the right and left FAs at each motion segment was calculated. FT was defined as an angle difference larger than the mean and one standard deviation of the angle differences between the right and left FAs at each motion segment in the group without disc herniation. OUTCOME MEASUREMENTS: Statistical significance of the bilateral angle difference of each lower lumbar motion segment between the two groups was analyzed by the two-sample t test. Using the defined angle difference for FT, the incidence of FT in the two groups at each motion segment was analyzed by the Fisher's exact test. RESULTS: FT was defined for the 33 subjects without disc herniation on CT scans as an angle difference larger than 12 degrees at L3 L4, 15 degrees at L4-L5, and 12 degrees at L5-S1, approximately. There was no statistical significance in the bilateral FA difference (p > .05) and incidence of FT (p > .05) at each segment between the two groups. CONCLUSION: This study did not show that facet joint tropism plays a significant role in disc herniation in the lower lumbar spine. PMID- 9365352 TI - Head and shoulder posture variations in 160 asymptomatic women and men. AB - OBJECTIVE: To quantitatively describe the postural alignment of the head and shoulders and the surface curvature of the thoracic spine in comfortable erect standing and to examine the effect of age and gender on head and shoulder alignment. DESIGN: Descriptive survey. SETTING: Gait research laboratory. PARTICIPANTS: One hundred sixty asymptomatic volunteers aged between 17 and 83 years. MAIN OUTCOME MEASURES: Five photographic measurements of head and shoulder posture in the coronal and sagittal planes and a photographic measurement of the surface curvature of the thoracic spine in the sagittal plane. RESULTS: Mean values of coronal head tilt, coronal shoulder angle, sagittal head tilt, sagittal C7-tragus angle, and sagittal shoulder-C7 angle were 180.1 degrees, 181 degrees, 172.1 degrees, 131.1 degrees, and 53.7 degrees, respectively. The 95% confidence intervals for the means ranged between 1 degree and 3.8 degrees. For each of the head and shoulder measurements there was no significant gender difference (p = .33 to .99). Of the five measurements, only sagittal C7-tragus angle was significantly correlated with age (r = .44), and none was correlated with surface curvature of the thoracic spine. CONCLUSIONS: Head and shoulder posture was similar between genders. Only one postural description that has been described anecdotally was identified, i.e., that age was related to the position of the head with respect to the trunk in the sagittal plane, although the strength of the association was of questionable clinical significance. In contrast, other longstanding assumptions were not supported, and accordingly, a forward head was not associated with increased thoracic curvature or upper cervical spine extension. PMID- 9365353 TI - Concentric and eccentric isokinetic assessment of flexor-extensor torque ratios at the hip, knee, and ankle in a sample population of healthy subjects. AB - OBJECTIVE: To establish the relationship between the flexor/extensor torque ratios in the hip, knee, and ankle. DESIGN: Case series. SETTING: Laboratory of a university rehabilitation department. PARTICIPANTS: From a group of 158 healthy volunteers, 138 subjects completed all the tests in concentric mode, and 65 in eccentric mode. MAIN OUTCOME MEASURE: The flexor/extensor torque ratios of the hip, knee, and ankle were analyzed by means of isokinetic concentric and eccentric tests. Analysis of variance was carried out to compare the mean values of the ratios obtained between the male and female populations and between the right and left sides, and correlation analysis between the values of the joints. RESULTS: The flexor/extensor torque ratios differed significantly according to sex and angular velocities, but not according to side except for the ankle. No significant relationship was found between the flexor/extensor torque ratios in the hip, knee, and ankle joints. CONCLUSIONS: The flexor-extensor torque ratio of the knee and hip can be used as a reference point during rehabilitation of the contralateral side. Our results demonstrating the absence of correlation between the flexor/extensor torque ratio in each joint of the same limb, however, call for further longitudinal studies to be made under specific circumstances, such as training or immobilization of one joint, to follow the course of agonist/antagonist ratios and the synergistic activity between the joints. PMID- 9365354 TI - Isokinetic strength training of the hemiparetic knee: effects on function and spasticity. AB - PURPOSE: To determine whether isokinetic training can improve the strength of the hemiparetic knee musculature, functional mobility, and physical activity and to evaluate its effect on spasticity in long-term stroke survivors. DESIGN: Nonrandomized self-controlled trial. SUBJECTS: A volunteer sample of 15 community dwelling stroke survivors of at least 6 months. INTERVENTION: A 6-week (3 days/week, 40 minutes/day) program consisting of warm-up, stretches, reciprocal knee extension and flexion isokinetic strengthening, and cool-down for the paretic limb. MAIN OUTCOME MEASURES: Peak isokinetic hamstring and quadriceps torque, quadriceps spasticity, gait velocity, timed Up and Go, timed stair climb, and the Human Activity Profile (HAP) scores were recorded at baseline, after training, and 4 weeks after training cessation (follow-up). RESULTS: Paretic muscle strength improved after training (p < .05) while tone remained consistent (p > .87). Gait velocity increased after training (p < .05) and at follow-up (p < .05). Changes in stair climbing and timed Up and Go were not significant (p > .37; p > .91), although subjects perceived gains in their physical abilities at follow-up (p < .01). CONCLUSIONS: Gains in strength and gait velocity without concomitant increases in muscle tone are possible after a short-term strengthening program for stroke survivors. The psychological benefit associated with physical activity is significant. PMID- 9365355 TI - Systematic home-based physical and functional therapy for older persons after hip fracture. AB - OBJECTIVE: To describe the development, implementation, and results of a home based rehabilitation protocol for older persons after hip fracture. DESIGN: Demonstration study. SETTING: Community. PARTICIPANTS: One hundred forty-eight community-living, nondemented participants at least 65 years of age who underwent repair of a fractured hip at two local hospitals. INTERVENTION: A linked assessment-intervention, home-based rehabilitation strategy. The physical therapy (PT) component of the intervention was designed to identify and ameliorate impairments in balance, strength, transfers, gait, and stair climbing; the functional therapy (FT) component was designed to identify and improve unsafe and/or inefficient performance of specific activities of daily living (ADL). MAIN OUTCOME MEASURES: The percentage of participants able to complete each component and the extent of progress noted in strength, balance, transfers, gait, and daily functioning. RESULTS: A total of 104 of the 148 participants (70%) completed the 6-month PT and FT program; 4 completed only PT and 6 refused both PT and FT. The remaining 32 participants (22%) received partial PT and FT that was terminated by death, hospitalization, or institutionalization. Seventy-seven percent of participants reported performing at least half of the recommended daily exercise sessions. Ninety-four percent and 96% of participants progressed in upper and lower extremity conditioning respectively; 33% progressed to the highest level in the graduated resisted exercise program. All participants progressed in the competency-based graded balance program, with 55% progressing to the fifth (most difficult) level. Similarly, the majority progressed in transfer maneuvers, stair climbing, and outdoor gait. One repetition maximum (RM) elbow extension increased from a mean of 5.8 (SD 4.6) pounds at baseline to 7.2 (SD 3.8) pounds at 6mo (t 2.22; p < .02). One RM knee extension increased from 5.8 (SD 5.8) pounds to 10.8 (SD 5.4) pounds (t = 8.06; p < .0001). The number of gait deviations decreased from 2.1 (SD 1.3) to 0.6 (SD 0.9) (p < .0001), while the mean modified Berg Balance Scale Score increased from 13.0 (SD 4.8) to 20.5 (SD 6.8) (t = 16.6; p < .0001). Finally, the Total ADL Score increased from a mean of 48.2 (SD 15.0) to 77.7 (SD 18.8) (t = 17.03; p = .0001). CONCLUSIONS: This systematic assessment and intervention protocol, targeting impairments and ADL, was feasible, safe, and effective. Protocols such as the one presented should enhance the ability to implement rehabilitation programs for the increasing number of multiply impaired older persons receiving home-based therapy and to document the process and outcomes of this care. PMID- 9365356 TI - Alcohol abuse and traumatic brain injury: effect on event-related potentials. AB - OBJECTIVE: To examine the individual and combined impact that traumatic brain injury (TBI) and heavy social use of alcohol have on electrophysiologic correlates of working memory and evaluation of task-relevant information. DESIGN: Case-control study. SETTING: University hospital brain injury rehabilitation unit. PARTICIPANTS: Forty male volunteers divided into four groups on the basis of their history of TBI and alcohol intake. Subjects with TBI had experienced a severe closed head injury at least 1 year before testing. MAIN OUTCOME MEASURE: Event-related potentials (ERPs) and neuropsychometric tests. RESULTS: Groups showed no significant differences in average age or neuropsychological tests. TBI groups did not differ in time postinjury or on severity measures. Alcohol use measures were significantly greater in the two alcohol groups. N200 latency and P300 amplitude were impaired in heavy social drinkers and in nondrinking subjects with TBI relative to controls, but were significantly impaired in subjects with TBI who were also heavy social drinkers. CONCLUSION: The results indicate that although alcohol use and TBI independently produce mile alterations in some aspects of late ERP components, the ERP changes are significantly greater when alcohol use and TBI are combined. This study provides evidence that heavy social drinking after TBI has a measurable impact on electrophysiologic correlates of cognition. PMID- 9365357 TI - Concordance of patients' and family members' ratings of neurobehavioral functioning after traumatic brain injury. AB - OBJECTIVE: To examine differences in family and patient evaluation of neurobehavioral functioning in adults with traumatic brain injury (TBI). DESIGN: Differences were examined by conducting 70 paired sample t tests on scale items and 6 paired sample t tests on scale scores from a neurobehavioral inventory. SETTING: Medical center outpatient clinic. PARTICIPANTS: Three hundred one consecutive adult patients with TBI and 301 informants, primarily family members, completed the neurobehavioral inventory. MAIN OUTCOME MEASURE: Neurobehavioral Functioning Inventory (NFI) comprised of six scales with items describing symptoms and daily living problems. RESULTS: Paired t test analyses of the six scales indicated that patients reported a significantly greater level of communication problems than did their matched family members. No differences were found for the other five scales. Paired t test analyses of the 70 scale items revealed significant differences in patient and family ratings for only 13 items. In all 13 instances, patients reported greater levels of dysfunction than were reported by their family members. Analysis of variance (ANOVA) indicated a main effect of injury severity for only the Communication and Memory/Attention scales. CONCLUSIONS: Findings indicate general agreement between family members and patients regarding patients' everyday problems. Results do not support contentions that patients tend to underestimate difficulties. Agreement levels appear related to injury severity, item specificity, and item content. More research is needed to identify other variables relating to agreement levels, including age, injury severity, and amount of contact between patients and family members. PMID- 9365359 TI - Total contact casts: pressure reduction at ulcer sites and the effect on the contralateral foot. AB - OBJECTIVE: To compare the effectiveness of total contact casts with a cast boot (TCCB), total contact casts with a cast heel (TCCH), and therapeutic XtraDepth shoes (XDS) to reduce ulcer site pressures and to determine if total contact casts increase contralateral pressures. DESIGN: Repeat measure design with 40 replications nested within each treatment for each patient. METHODS: Peak contralateral foot pressures and ulcer site pressures under the 1st metatarsal (1MET; n = 10), 2nd to 5th metatarsals (2-5MET; n = 10), and great toe (GT; n = 5) were compared using the Novel-Pedar system and three treatments: TCCB, TCCH, and XDS. Baseline pressures were established using canvas oxfords. RESULTS: There was no difference in pressure reduction with TCCH vs. TCCB for 1MET or GT ulcers, but TCCH reduced pressure better for 2-5MET ulcers (p < .001). Contralateral pressures were not elevated in either TCC group. CONCLUSIONS: TCCH were superior to TCCB in reducing 2-5MET ulcer pressures and equivalent to TCCB for 1MET and GT ulcers. Contralateral pressures are not increased by TCC use. PMID- 9365358 TI - Isometric abduction muscle activation in patients with rotator tendinosis of the shoulder. AB - OBJECTIVE: To examine the influence of pain on activation in brief maximal and sustained submaximal isometric abduction in patients with rotator tendinosis of the shoulder. DESIGN: Randomized, controlled experimental trial. PARTICIPANTS: Ten patients with complaints of at least 3 months' duration (median range, 1 to 2 years) and nine healthy controls. INTERVENTION: Patients and controls were randomized into subacromial local anesthetic injection on 2 different days. METHODS: The uninvolved shoulder was tested first, elbow flexed 90 degrees, shoulder abducted 45 degrees. The protocol consisted of three brief maximal voluntary contractions (MVCs), followed by a sustained submaximal contraction until exhaustion and three MVCs during a 20-minute recovery period. Electromyography (EMG) was obtained bilaterally from the supraspinatus, infraspinatus, upper trapezius, and middle deltoid muscles. Pain was scored on a visual analogue scale (0 to 100). RESULTS: Mean pain rating on MVC of the involved side of patients was reduced from 28 to 10 by subacromial injection. Mean MVC force improved from 163N to 184N (95% confidence interval for the difference, 14 to 29N). The accompanying EMG amplitude during MVC increased significantly in three of the four muscles examined. Pain, force, and EMG of the uninvolved side and in controls were unaltered. Endurance time and EMG (given as microV) during the submaximal contraction were not influenced by pain. MVC did not fully recover during the postexhaustive period, while the corresponding EMG amplitudes were comparable to values in unfatigued muscle. CONCLUSION: Pain reduced central motor drive during maximal efforts in the unfatigued state, but no additional reduction was seen after a sustained submaximal contraction. PMID- 9365360 TI - Bruxism after brain injury: successful treatment with botulinum toxin-A. AB - Bruxism, the rhythmic grinding of teeth--usually during sleep--is not an infrequent complication of traumatic brain injury. Its prevalence in the general population is 21%, but its incidence after brain injury is unknown. Untreated, bruxism causes masseter hypertrophy, headache, temporomandibular joint destruction, and total dental wear. We report a case of complete resolution of postanoxic bruxism after treatment with botulinum toxin-A (BTX-A). The patient was a 28-year-old man with no history of bruxism who sustained an anoxic brain injury secondary to cardiac arrest of unknown etiology. On admission to our rehabilitation unit 2 months after the injury, the patient presented with severe bruxism and heavy dental wear. The patient was injected with a total of 200 units of BTX-A to each masseter and temporalis. There was total resolution of bruxism 2 days after injection, with no complications. On follow-up 3 months after injection, the patient remained free of bruxism. We propose that botulinum toxin be considered as a treatment for bruxism secondary to anoxic brain injury. Further studies regarding muscle selection and medication dosage are warranted to elucidate the toxin's efficacy in this condition. PMID- 9365361 TI - Multiple sclerosis presenting as a spinal cord tumor. AB - Multiple sclerosis, a disorder of central nervous system demyelination, is a leading cause of disability in young people. Lesions of the spinal cord are usually less than two vertebral body segments long, peripherally located, and found in the cervical region. A 30-year-old woman had a 2-month history of back pain, urinary incontinence, and bilateral lower extremity weakness. Magnetic resonance imaging (MRI) of the spine showed an intramedullary spinal cord tumor from T4 to T8 with an intramedullary cyst from T1 to T4. After thoracic decompressive surgery, findings from biopsy of the cord lesion were consistent with multiple sclerosis. Postoperatively, the patient required an intensive rehabilitation program. This is the first reported case of histopathologically confirmed spinal cord demyelination presenting as an intramedullary thoracic cord tumor. Physiatrists should be alerted that demyelinating disease can mimic a spinal cord tumor, even on MRI, and must be considered in the differential diagnosis of a symptomatic spinal cord mass. PMID- 9365362 TI - Persisting impairment following Rocky Mountain Spotted Fever: a case report. AB - A patient initially presented in the emergency room with fever, confusion, and a petechial rash. Rocky Mountain Spotted Fever (RMSF) was diagnosed and appropriate treatment was initiated. He subsequently became obtunded and required mechanical ventilation and temporary cardiac pacing. Four weeks later, he presented to our rehabilitation unit with ataxia, hyperreflexia and upper motor neuron signs, dysesthesias, sensorimotor axonopathy demonstrated by electrodiagnostic studies, and a global decrement in cognitive capability. Although he significantly improved in functional mobility and self-care, he exhibited little improvement in his cognitive impairment at 6-month follow-up. An understanding of the natural history of, and long-term impairments associated with, RMSF will be helpful to physiatrists in developing rehabilitation care plans and in assisting such patients with community re-entry. PMID- 9365363 TI - Evidence-based PM&R? PMID- 9365364 TI - Skeletal muscle metabolism in myotonic dystrophy A 31P magnetic resonance spectroscopy study. AB - We have used 31P magnetic resonance spectroscopy to investigate skeletal muscle bioenergetics in a total of 31 patients with myotonic dystrophy. Results from resting flexor digitorum superficialis and calf muscle showed a significant elevation in the concentration ratio of inorganic phosphate to ATP and a significant reduction in the phosphorylation potential. In addition, in resting calf muscle the concentration ratio of phosphocreatine to ATP was reduced, and the resting intracellular pH and calculated free cytosolic ADP concentration were elevated. In general, the abnormalities observed were more marked in those patients who were more severely affected as judged by their ability to exercise. During aerobic exercise in both calf muscle and flexor digitorum superficialis, phosphocreatine was depleted more rapidly in patients than in control subjects but the muscle acidified less and ADP concentrations were higher. Calculated ATP turnover was significantly elevated. Analysis of the recovery kinetics for phosphocreatine following exercise provides evidence for a small but significant reduction in mitochondrial function. Analysis of the response of flexor digitorum superficialis to ischaemic exercise provides evidence of a reduction in the relative utilization of glycogen to produce ATP which may account, in part, for the reduced acidification seen in exercising muscle in myotonic dystrophy. There was no definite evidence of an alteration in proton handling capacity in this condition. PMID- 9365365 TI - Molecular pathology of MELAS and MERRF. The relationship between mutation load and clinical phenotypes. AB - Many patients with inherited mitochondrial encephalopathies have one of two pathogenic mutations of mitochondrial DNA (mtDNA): A3243G or A8344G. Individuals who harbour these mutations carry both mutant and wild-type alleles within each cell (heteroplasmy). Despite clear evidence of a direct relationship between the level of mutation and mitochondrial respiratory chain function in vitro, it has been more difficult to demonstrate a clear correlation between clinical phenotype and the level of mutant mtDNA in vivo. To address this issue, we identified 245 individuals who carry either the A3243G or A8344G mutations, and studied the relationship between the incidence of specific clinical features and the level of mutant mtDNA in blood (for A3243G, n = 73; for A8344G, n = 25) and/or skeletal muscle (for A3234G, n = 111; for A8344G, n = 55). Within this study group, the frequency of key clinical features was significantly different for individuals harbouring the A3243G and A8344G mutations. For both mutations, there was a correlation between the frequency of the more common clinical features and the level of mutant mtDNA in muscle. In contrast, we did not observe a correlation between the frequency of clinical features and the level of mutant mtDNA in blood. Therefore, measurement of the level of the A3243G and A8344G mutations in muscle will allow the identification of individuals who are at risk of developing specific complications, thus improving the prognostic advice that can be given to patients and family members who carry these mutations. PMID- 9365366 TI - Phenotypic heterogeneity in motor neuron disease patients with CuZn-superoxide dismutase mutations in Scandinavia. AB - Four-hundred and fifty-one blood samples from Scandinavian patients with motor neuron disease were analysed for mutations in the CuZn-superoxide dismutase gene. Forty-one (9.6%) of the 427 patients with the amyotrophic lateral sclerosis (ALS) form of the disease were found to have a disease-associated mutation, and 14 of these patients were apparently sporadic cases. A mutation was found in 12 of the 51 families with recognized familial ALS. The five different mutations found (Ala4Val, Val14Gly, Asp76Tyr, Asp90Ala, Gly127insTGGG) have different genetic characteristics and are associated with very variable phenotypes spanning from rapidly progressing disease with only lower motor neuron signs to very slowly progressing disease with both the upper and lower motor neuron systems affected. The patients showed different sites of onset, though the progressive bulbar palsy form of the disease appears to be rare among patients with a CuZn-superoxide dismutase mutation. The progression of motor signs and symptoms followed the same basic pattern in patients with different mutations. Extra-motor system symptoms were frequent among patients with a CuZn-superoxide dismutase mutation. The results suggest that patients with mutations in the CuZn-superoxide dismutase gene constitute one disease entity. The Val14Gly and Asp76Tyr mutations have not been reported before, and the latter is the first mutation to be found in exon 3 of the CuZn-superoxide dismutase gene. PMID- 9365367 TI - Genetic disorders and cerebellar structural abnormalities in childhood. AB - Amongst 78 patients with either unilateral or bilateral (ponto-) cerebellar hypoplasia, atrophy or lesions on neuro-imaging (CT and/or MRI), 16 showed unilateral hypoplasia or lesions, 15 vermis defects, nine pontocerebellar hypoplasia, 10 non-progressive conditions with bilateral cerebellar hemisphere hypoplasia or lesions and 28 progressive cerebellar atrophy. Known genetic conditions did not occur with unilateral cerebellar involvement, whereas a high incidence of mostly autosomal recessively inherited diseases could be diagnosed in more than half of the patients with either pontocerebellar hypoplasia or progressive bilateral cerebellar atrophy. A minority of patients with vermis defects or non-progressive cerebellar hypoplasia suffered from genetic conditions. An overview of the literature is presented describing genetic and non genetic syndromes, or metabolic disorders associated with cerebellar structural abnormalities. From these data, new proposals for improved diagnostic investigations will be presented. PMID- 9365368 TI - Cerebellum and procedural learning: evidence from focal cerebellar lesions. AB - The aim of the present study was to investigate the influence of focal cerebellar lesions on procedural learning. Eight patients with cerebellar lesions and six control subjects were tested in a serial reaction-time task. A four-choice reaction-time task was employed in which the stimuli followed (or not) a sequence repeated 10 times, with the subjects aware (or not) of the item sequence. Learning was manifested by the reduction in response latency over the sequential blocks. Acquisition of declarative knowledge of the sequence was also tested. Reaction times displayed by patients with cerebellar lesions, even though they tended to be longer than those of control subjects in all testing conditions, significantly differed from control subjects only when the stimuli were presented in sequence. The reaction times in sequential trials were still statistically significant when simple motor response times were taken into account. Cerebellar patients were also significantly impaired in detecting and repeating the sequence. On the other hand, when the sequence was learned before testing, motor performances were significantly improved in all subjects. These data indicate that cerebellar lesions induce specific impairment in the procedural learning of a motor sequence and suggest a role of the cerebellar circuitry in detecting and recognizing event sequences. PMID- 9365369 TI - Brain activity during observation of actions. Influence of action content and subject's strategy. AB - PET was used to map brain regions that are associated with the observation of meaningful and meaningless hand actions. Subjects were scanned under four conditions which consisted of visually presented actions. In each of the four experimental conditions, they were instructed to watch the actions with one of two aims: to be able to recognize or to imitate them later. We found that differences in the meaning of the action, irrespective of the strategy used during observation, lead to different patterns of brain activity and clear left/right asymmetries. Meaningful actions strongly engaged the left hemisphere in frontal and temporal regions while meaningless actions involved mainly the right occipitoparietal pathway. Observing with the intent to recognize activated memory-encoding structures. In contrast, observation with the intent to imitate was associated with activation in the regions involved in the planning and in the generation of actions. Thus, the pattern of brain activation during observation of actions is dependent both on the nature of the required executive processing and the type of the extrinsic properties of the action presented. PMID- 9365370 TI - Neural mechanisms involved in the processing of global and local aspects of hierarchically organized visual stimuli. AB - We investigated the functional anatomy involved in sustaining or switching visual attention between different perceptual levels, using functional imaging measures of neural activity. Two experiments were carried out using hierarchically organized letters (i.e. large letters made out of small letters). In a divided attention task, subjects were required to switch attention between local and global levels. The number of successive stimuli for which subjects had to sustain attention to either the global or local level co-varied significantly with temporal-parietal activations bilaterally. Other activations were also observed in the right orbitofrontal cortex, the right dorsolateral prefrontal cortex, and the right middle temporal gyrus. The number of switches between levels co-varied significantly with activations in the left supplementary motor area and the left medial parietal cortex. In the directed-attention task, subjects were required to attend to either the global or local level of the stimuli throughout all trials; attention to the global aspect resulted in significant activation of the right lingual gyrus while attention to the local aspect significantly activated the left inferior occipital cortex. We suggest that left hemisphere activations with increasing numbers of switches between perceptual levels reflect increased demands on an executive attentional system, while sustained attention to either level activates a predominantly right hemispheric network involving temporal parietal and dorsolateral prefrontal regions. Overall, the results provide evidence for relative hemispheric specialization for global and local processing in accordance with previous neuropsychological studies. In addition, the findings demonstrate that early visual processing mechanisms in the prestriate cortex are influenced by an attentional system in temporal-parietal areas. PMID- 9365371 TI - Speechreading in the akinetopsic patient, L.M. AB - Patient L.M. has a well-documented, long-standing and profound deficit in the perception of visual movement, following bilateral lesions of area V5 (visual movement cortex). Speechreading was explored in this patient in order to clarify the extent to which the extraction of dynamic information from facial actions is necessary for speechreading. Since L.M. is able to identify biological motion from point-light displays to whole-body forms and has some limited visual motion capabilities, we expected that some speechreading of faces in action would be possible in this patient. L.M.'s reading of natural speech was severely impaired, despite unimpaired ability to recognize speech-patterns from face photographs and reasonable identification of monosyllables produced in isolation. She was unable to track multisyllabic utterances reliably and was insensitive to vision when incongruent audiovisual speech syllables were shown. Point-light displays of speech were as poorly read as whole face displays. Rate of presentation was critical to her performance. With speech, as with other visual events, including tracking the direction of gaze and of hand-movement sequences, she could report actions that unfolded slowly (approximately one event per 2 s). In line with this, she was poor at reporting whether seen speech rate was normal, fast (double speed) or slow (half-speed). L.M.'s debility is the converse of that reported for a patient with lesions primarily to V4 (H.J.A.), who is unable to speechread photographs of faces but can speechread moving faces. The visual analysis of both form and motion is required for speechreading; the neural systems that support these analyses are discussed. PMID- 9365372 TI - A study of the performance of patients with frontal lobe lesions in a financial planning task. AB - It has long been argued that patients with lesions in the prefrontal cortex have difficulties in decision making and problem solving in real-world, ill-structured situations, particularly problem types involving planning and look-ahead components. Recently, several researchers have questioned our ability to capture and characterize these deficits adequately using just the standard neuropsychological test batteries, and have called for tests that reflect real world task requirements more accurately. We present data from 10 patients with focal lesions to the prefrontal cortex and 10 normal control subjects engaged in a real-world financial planning task. We also introduce a theoretical framework and methodology developed in the cognitive science literature for quantifying and analysing the complex data generated by problem-solving tasks. Our findings indicate that patient performance is impoverished at a global level but not at the local level. Patients have difficulty in organizing and structuring their problem space. Once they begin problem solving, they have difficulty in allocating adequate effort to each problem-solving phase. Patients also have difficulty dealing with the fact that there are no right or wrong answers nor official termination points in real-world planning problems. They also find it problematic to generate their own feedback. They invariably terminate the session before the details are fleshed out and all the goals satisfied. Finally, patients do not take full advantage of the fact that constraints on real-world problems are negotiable. However, it is not necessary to postulate a 'planning' deficit. It is possible to understand the patients' difficulties in real world planning tasks in terms of the following four accepted deficits: inadequate access to 'structured event complexes', difficulty in generalizing from particulars, failure to shift between 'mental sets', and poor judgment regarding adequacy and completeness of a plan. PMID- 9365373 TI - Frontal-striatal cognitive deficits in patients with chronic schizophrenia. AB - Spatial working memory and planning abilities were assessed in 36 hospitalized patients with chronic schizophrenia, using the computerized Cambridge Neuropsychological Test Automated Battery (CANTAB), and compared with those of normal subjects and patients with neurological disorders (frontal lobe lesions; temporal lobe and amygdalohippocampal lesions; Parkinson's disease), matched for age, sex and National Adult Reading Test IQ. The patients in the group with temporal lobe lesions were unimpaired in their performance on these tasks. Patients with schizophrenia were impaired on visuo-spatial memory span compared with all the other groups, while severity of Parkinson's disease was correlated with the degree of impairment on this task. The patients with schizophrenia and those with frontal lobe lesions were impaired on a 'spatial working memory' task, with increased 'between-search errors'. Patients with Parkinson's disease performed this task poorly compared with the younger control subjects. Patients with schizophrenia were unable to develop a systematic strategy to complete this task, relying instead on a limited visuo-spatial memory span. Higher level planning ability was investigated using the CANTAB 'Tower of London'. All groups were equally able to complete the task. However, the groups of patients with schizophrenia and frontal lobe lesions made fewer perfect solutions and required more moves for completion. Movement times were significantly slower in the schizophrenia group, suggesting impairment in the sensorimotor requirements of the task. The patients with schizophrenia were not impaired in their 'initial thinking' (planning) latencies, but had significantly prolonged 'subsequent thinking' (execution) latencies. This pattern resembled that of the group with frontal lobe lesions and contrasted with the prolonged 'initial thinking' time seen in Parkinson's disease. The results of this study are indicative of an overall deficit of executive functioning in schizophrenia, even greater than that seen in patients with frontal lobe lesions. However, the pattern of results in schizophrenia resembled that seen in patients with lesions of the frontal lobe or with basal ganglia dysfunction, providing support for the notion of a disturbance of frontostriatal circuits in schizophrenia. Our findings also indicate that there is a loss of the normal relationships between different domains of executive function in schizophrenia, with implications for impaired functional connectivity between different regions of the neocortex. PMID- 9365374 TI - Contribution of medial versus lateral temporal-lobe structures to human odour identification. AB - To investigate possible distinct contributions of different temporal-lobe structures to odour identification, the University of Pennsylvania Smell Identification Test was administered monorhinally to seizure-free patients who had undergone one of three types of temporal-lobe resection practised in three different institutions for surgical treatment of epilepsy. The resections were neocorticectomy (Dublin), selective amygdalohippocampectomy (Zurich), or anterior temporal-lobe resection with encroachment on amygdala and hippocampus (Montreal). Resections, analysed from MRI scans, showed unexpected encroachment on medial structures in most patients of the neocorticectomy groups, and largest amygdala and hippocampal resections in the amygdalohippocampectomy groups. Impaired odour identification was observed in all patient groups, irrespective of surgical approach, with greatest impairment in the nostril ipsilateral to the resection. The finding of deficits in all three surgical groups suggests that damage in the anterior temporal area, perhaps in piriform cortex, is sufficient to disrupt performance on this task; it may be that function is disrupted in the medial temporal-lobe region by disconnection when the periamygdaloid area is damaged, even when amygdala and hippocampus are left intact. An alternative explanation for our results is that damage in any one of these areas disrupts a complex network involving several distinct temporal-lobe structures. PMID- 9365375 TI - Photophobia and autonomic responses to facial pain in migraine. AB - Subjective and autonomic responses to visual stimulation and facial pain were investigated in 10 migraine sufferers and 21 'non-headache' control subjects. Ratings of glare- and light-induced pain were greater in migraine sufferers than control subjects. In migraine sufferers, glare ratings increased during painful mechanical stimulation of the nasal ala, the side of the nose and the back of the neck. Glare ratings decreased in both groups during painful stimulation of the chin. Light-induced pain increased during painful stimulation of all four sites in migraine sufferers, but not control subjects. Increases in forehead pulse amplitude during painful mechanical stimulation were greater bilaterally in migraine sufferers than in control subjects, consistent with loss of inhibitory influences on vascular reactions in the face. Visual stimulation facilitated lacrimation when the nasal ala was pinched, but visual stimulation coupled with pain elsewhere in the head and neck did not. The lacrimal response to combined nasal ala and visual stimulation was absent on the symptomatic side in patients with unilateral headache, indicating local parasympathetic deficit in migraine. These findings suggest that migraine is associated with loss of inhibitory subcortical processes which normally suppress sensations of glare and light induced pain, and which may also suppress vasodilator responses to facial pain. Loss of inhibitory pain-control mechanisms could interact in a vicious circle with autonomic disturbances during migraine. PMID- 9365376 TI - Regional hippocampal [11C]flumazenil PET in temporal lobe epilepsy with unilateral and bilateral hippocampal sclerosis. AB - Using statistical parametric mapping and [11C]flumazenil (FMZ) PET we have previously shown reduction of central benzodiazepine receptor (cBZR) binding restricted to the hippocampus in mesial temporal lobe epilepsy due to unilateral hippocampal sclerosis. However, bilateral hippocampal pathology can be present in up to 50% of patients with mesial temporal lobe epilepsy. Additionally, the limited spatial resolution of PET results in a partial volume effect that affects quantitative analysis of cBZRs and such an effect can mask hippocampal dysfunction. We analysed changes in the [11C]FMZ volume of distribution (FMZ-Vd) before and after correction for partial volume effect in six patients with refractory mesial temporal lobe epilepsy and a quantitative MRI diagnosis of bilateral hippocampal sclerosis, which appeared either symmetrical on MRI (bilateral symmetrical hippocampal sclerosis; three patients) or bilateral but asymmetrical (asymmetrical hippocampal sclerosis; three patients), and in nine patients with refractory mesial temporal lobe epilepsy and unilateral hippocampal sclerosis on MRI than was subsequently histologically verified. Fifteen healthy controls were also studied for comparison. Before correction for partial volume effects, significant unilateral reductions of FMZ-Vd were found in one of the three patients with bilateral symmetrical hippocampal sclerosis, in one of the three asymmetrical hippocampal sclerosis patients and in six of the nine unilateral hippocampal sclerosis patients. No significant bilateral reductions of hippocampal FMZ-Vd were detected. After correction for partial volume effect, all three patients with bilateral symmetrical hippocampal sclerosis showed significant bilateral reductions of FMZ-Vd, and these were asymmetrical in two. All three patients with asymmetrical hippocampal sclerosis and all nine patients with unilateral hippocampal sclerosis on MRI showed unilateral reductions of FMZ Vd concordant with the side of the EEG focus. In addition one of the three patients with asymmetrical hippocampal sclerosis and three of the nine patients with unilateral hippocampal sclerosis showed significant reductions of FMZ-Vd in the hippocampus contralateral to the side of the EEG focus. Absolute quantification of [11C]FMZ-PET, corrected for partial volume effect, within multiple hippocampal volumes of interest was necessary in order to detect bilateral changes of cBZR in mesial temporal lobe epilepsy due to hippocampal sclerosis with optimal sensitivity. This [11C]FMZ-PET approach was able to demonstrate subtle contralateral abnormalities in one-third of patients thought to have unilateral or bilateral asymmetrical hippocampal sclerosis on MRI. Reduction of cBZR binding was consistently over and above loss of hippocampal volume indicating that atrophy is not the sole determinant of cBZR loss in mesial temporal lobe epilepsy. PMID- 9365377 TI - Distinctive abnormalities of facial reflexes in patients with progressive supranuclear palsy. AB - Spontaneous and voluntary eyelid motility is often abnormal in patients with progressive supranuclear palsy. In contrast, their eyelid reflex responses are relatively preserved, and only those generated by an acoustic startle have been found absent or severely reduced. We hypothesized that, because of their relevant brainstem pathology, patients with progressive supranuclear palsy might have other brainstem reflex abnormalities which, on detection, could help with their neurophysiological characterization. In this study, we examined facial reflex responses in 14 patients with progressive supranuclear palsy, 12 patients with multisystem atrophy, 10 patients with Parkinson's disease, six patients with corticobasal ganglionic degeneration, 11 patients with various non-parkinsonian neurological illnesses and 10 normal subjects. EMG activity was simultaneously recorded from the orbicularis oculi and mentalis muscles following electrical stimulation of the median nerve at the wrist. Mentalis responses were obtained in two normal subjects and in all patients except one with Parkinson's disease, one with progressive supranuclear palsy and one with corticobasal ganglionic degeneration; there were no differences between groups of subjects regarding latency or peak amplitude. Orbicularis oculi responses were always present in control subjects and patients who exhibited mentalis responses, with the significant exception of patients with progressive supranuclear palsy, in whom only the response of mentalis was obtained. Blink-reflex responses to supraorbital nerve electrical stimuli were present at a normal latency and amplitude in all patients. An abnormally enhanced blink-reflex excitability recovery curve to paired stimuli was found in a similar percentage of patients with progressive supranuclear palsy, multisystem atrophy and Parkinson's disease, but in only two patients with corticobasal ganglionic degeneration. Patients with progressive supranuclear palsy have a functional involvement of circuits mediating orbicularis oculi responses to median nerve electrical stimuli, that is a distinctive feature with respect to other parkinsonian syndromes. PMID- 9365378 TI - Power spectrum analysis of heart rate variability in Guillain-Barre syndrome. A longitudinal study. AB - Power spectrum analysis of heart rate variability was repeatedly carried out on 13 patients with Guillain-Barre syndrome for up to 1 year by Fourier analysis of regular beat-to-beat (R-R) intervals which were recorded for 5 min, converted into a continuous function by linear interpolation and resampled at 5 Hz. Low frequency (LF) power (reflecting a mixture of parasympathetic and sympathetic activity) and high-frequency (HF) power (reflecting parasympathetic tone) were calculated by integrating the spectra from 0.04 to 0.15 Hz and from 0.15 to 0.4 Hz, respectively. At the height of the disease, the HF component was significantly decreased. The LF:HF ratio, which has been suggested to be an indicator for sympathetic activity, was increased compared with the follow-up value after 1 year. Both measures returned to normal gradually over time. Pooled data analysis suggested that both HF and LF power were significantly related to the responses of standardized parasympathetic function tests, while the LF:HF ratio was inversely correlated with sympathetic vasomotor activity. In patients presenting with tachycardia, LF and HF power were strikingly decreased compared with patients with normal heart rates, while in patients showing vagal over reactivity, the power of both spectral bands was significantly increased. The results suggest that spectral analysis of heart rate variability is useful for investigating the cardiovascular neural regulation in patients with Guillain Barre syndrome. In this disorder, the sympathovagal balance is clearly shifted to sympathetic predominance at the height of the disease. PMID- 9365379 TI - A combined inhibitor of matrix metalloproteinase activity and tumour necrosis factor-alpha processing attenuates experimental autoimmune neuritis. AB - Matrix metalloproteinases (MMPs) and the cytokine tumour necrosis factor (TNF) alpha are implicated in the pathology of inflammatory demyelinating diseases of the CNS, and may also be involved in peripheral demyelinating diseases such as acute inflammatory demyelinating polyradiculoneuropathy. We have tested an inhibitor of MMP activity and TNF-alpha processing, BB-1101, in experimental autoimmune neuritis (EAN), an animal model of Guillain-Barre syndrome. Treatment with BB-1101 from the time of immunization prevented the development of EAN, and when given from the onset of symptoms, it significantly reduced disease severity. These results indicate that MMPs and/or TNF-alpha are involved in the pathogenesis of EAN, and that drugs of this type may have potential as novel therapeutic agents in the therapy of peripheral nervous system demyelinating diseases. PMID- 9365380 TI - Abnormalities of ocular motility in myotonic dystrophy. PMID- 9365382 TI - The course of cortico-hypoglossal projections in the human brainstem: functional testing using transcranial magnetic stimulation. PMID- 9365383 TI - C-reactive protein--undervalued, underutilized. PMID- 9365381 TI - The course of cortico-hypoglossal projections in the human brainstem: functional testing using transcranial magnetic stimulation. PMID- 9365384 TI - The cloning debates and progress in biotechnology. PMID- 9365385 TI - Molecular diagnostics of infectious diseases. AB - Over the past several years, the development and application of molecular diagnostic techniques has initiated a revolution in the diagnosis and monitoring of infectious diseases. Microbial phenotypic characteristics, such as protein, bacteriophage, and chromatographic profiles, as well as biotyping and susceptibility testing, are used in most routine laboratories for identification and differentiation. Nucleic acid techniques, such as plasmid profiling, various methods for generating restriction fragment length polymorphisms, and the polymerase chain reaction (PCR), are making increasing inroads into clinical laboratories. PCR-based systems to detect the etiologic agents of disease directly from clinical samples, without the need for culture, have been useful in rapid detection of unculturable or fastidious microorganisms. Additionally, sequence analysis of amplified microbial DNA allows for identification and better characterization of the pathogen. Subspecies variation, identified by various techniques, has been shown to be important in the prognosis of certain diseases. Other important advances include the determination of viral load and the direct detection of genes or gene mutations responsible for drug resistance. Increased use of automation and user-friendly software makes these technologies more widely available. In all, the detection of infectious agents at the nucleic acid level represents a true synthesis of clinical chemistry and clinical microbiology techniques. PMID- 9365386 TI - Graphical interpretation of analytical data from comparison of a field method with reference method by use of difference plots. AB - Various viewpoints have been offered regarding the appropriate use of scatter plots or difference plots (bias plots or residual plots) in comparing analytical methods. In many of these discussions it seems the basic concepts of identity (within inherent imprecision) and acceptability based on analytical goals (analytical quality specifications) have been forgotten. With the increasing number of Reference Methods in laboratory medicine, these basic concepts are becoming more important in validation of field methods. Here we describe a simple and effective graphical test of these hypotheses (identity and acceptability) by use of difference plots. These plots display the underlying hypothesis before the measured differences are plotted and allow interpretation of the results according to specific criteria. We further describe simple but effective interpretations of the data, when the hypothesis is not fulfilled, by using two data sets drawn from comparisons of field methods for S-creatinine with a Reference Method for this analyte. The difference plot is a graphical tool with related simple statistics for comparison of a field method with a Reference Method, focusing on (a) identity within the inherent analytical imprecision or (b) acceptability within analytical quality specifications. Calculation of the standard deviation of the differences is an indispensable tool for evaluation of aberrant-sample bias (matrix effects). PMID- 9365388 TI - Direct comparison of performance characteristics of two immunoassays for bone isoform of alkaline phosphatase in serum. AB - A clinical need exists for a sensitive and specific assay for the quantitation of the bone isoform of alkaline phosphatase in serum. The majority of methods do not meet this requirement; however, the recent development of immunoassays for this isoform may provide a solution. In a detailed evaluation of two immunoassays, we found a degree of imprecision that enables the discrimination of changes within the reference range. The cross-reactivity of the liver isoform was found to be between 7.1% and 12.7% when two different methods of assessment were used. The comparison of results with an electrophoretic procedure showed that the immunocapture method recovered less of the bone isoform in samples from children than in samples from patients with Paget disease; no such difference was found with the immunometric method. This suggests that the immunocapture antibody may discriminate between different bone isoforms in children whereas the immunometric assay does not. PMID- 9365387 TI - Improved detection of minor ischemic myocardial injury with measurement of serum cardiac troponin I. AB - This study compared the diagnostic accuracy of the measurement of serum cardiac troponin I (cTnI) with creatine kinase (CK) MB mass in patients with minor myocardial injury whose measured total CK activity did not exceed twice the upper reference limit (300 U/L for men; 200 U/L for women). Forty-eight consecutive patients presenting with chest pain and with in-hospital documentation of myocardial injury were enrolled. Electrocardiogram, echocardiogram, and serial serum CK-MB mass, cTnI, and total CK were measured over 36 h after admission. Peak total CK activity was within normal limits in 28 patients (58%). The mean (+/- SD) peak CK-MB mass and cTnI concentrations were: 16.4 (11.8) micrograms/L and 132 (13.0) micrograms/L; respectively. The peak biochemical marker index (defined as CK-MB or cTnI divided by its respective upper reference limit) was significantly (P < 0.05) higher for cTnI than for CK-MB from 7 to 36 h. The clinical sensitivity for detection of myocardial injury for cTnI was 100% [95% confidence interval (CI): 87.2% to 100%], compared with 81.8% (CI: 67.3% to 91.8%) for CK-MB. Thus, cTnI was more sensitive than CK-MB mass for detection of myocardial injury in patients with small increases of total CK. PMID- 9365389 TI - Evidence that serum NTx (collagen-type I N-telopeptides) can act as an immunochemical marker of bone resorption. AB - Previous studies have shown that immunoassay of urinary NTx (cross-linked N telopeptides of type I collagen) provides a responsive index of human bone resorption. Here we report by a sensitive immunoassay that NTx is present in serum and is suppressed appropriately in patients with Paget disease of bone by bisphosphonate antiresorptive therapy. The monoclonal antibody (1H11) developed against urinary NTx was applied in a sensitive chemiluminescence format. Results for human serum and urine showed parallel inhibition curves. The NTx concentrations in paired serum and urine samples from individual patients correlated well when urinary concentrations were normalized to creatinine concentrations (in premenopausal and postmenopausal women and Paget disease patients, r = 0.90, n = 60). The percentage of NTx suppression from baseline values for Paget disease patients on bisphosphonate therapy was similar for serum and urine. Blood samples drawn from bone marrow at the site of Pagetic lesions in three patients with active disease had as much as 10-fold higher concentrations of NTx than did peripheral blood samples drawn at the same time. The latter finding is consistent with other evidence showing that immunoreactive NTx originates directly during the proteolytic cleavage of bone collagen by osteoclasts rather than, e.g., by degradative processes occurring later in the liver and kidney. PMID- 9365390 TI - Evaluation of a near-patient test for C-reactive protein used in daily routine in primary healthcare by use of difference plots. AB - We have assessed the technical performance and robustness of NycoCard CRP Whole Blood, a near-patient test for C-reactive protein (CRP), when used in realistic daily routine situations in general practice clinics (GPC). Thirteen GPCs participated, five of them with technician staff. From 898 patients, split-sample measurements for CRP were made. Results from GPCs were compared with results from a turbidimetric laboratory method, traceable to international reference preparations (IFCC CRM 470). Results were evaluated in difference plots where the expected distribution, due to an estimated analytical variation, was compared with measured differences. Of all difference points, 91.5% (n = 819) were within a 95% prediction interval based on the imprecision of both methods. Mean bias (95% confidence interval) was -0.3 mg/L (-0.9 to 0.3). No differences in analytic quality were found between GPCs with technician staffs and GPCs without, and between test results obtained within the first and second week, compared with the rest of the study period. We find the test as good when used in GPCs as could be expected from laboratory testing, and consequently robust, which is a necessity for use in routine situations in general practice. General application of difference plots in test evaluations are discussed in detail. PMID- 9365391 TI - Improved purification of human bone sialoprotein and development of a homologous radioimmunoassay. AB - Bone sialoprotein (BSP) is a phosphorylated skeletal glycoprotein. Here we describe a new procedure for the purification of BSP involving wide-pore reversed phase HPLC, and the development of a homologous RIA for human BSP. The immunoassay showed linearity between 3 and 120 micrograms/L, a lower detection limit of 0.7 micrograms/L, and a mean recovery rate of 99.4%. Intraassay variation was 7.0% (mean = 10.9 micrograms/L) and 6.1% (mean = 38.8 micrograms/L), and interassay variation was 9.2% (mean = 11.1 micrograms/L) and 9.4% (mean = 39.0 micrograms/L). No cross-reactivity was detected with osteocalcin, osteonectin, or bone alkaline phosphatase. Preliminary clinical evaluation in healthy controls (n = 90) showed a mean serum BSP concentration on 12.1 +/- 5.0 micrograms/L (+/- SD). BSP was significantly increased in patients with Paget disease of bone, primary and secondary hyperparathyroidism, and also in subjects with renal failure without skeletal involvement. Impairment of hepatic function did not affect serum BSP concentrations. PMID- 9365392 TI - Differentiation between naproxen, naproxen-protein conjugates, and naproxen lysine in plasma via micellar electrokinetic capillary chromatography--a new approach in the bioanalysis of drug targeting preparations. AB - Pharmacotherapy through the targeting of drugs is a promising new approach that requires adequate analytical methods capable of differentiating between the free drug, the drug carrier, and metabolites. Using micellar electrokinetic capillary chromatography (MECC), we report the separation of naproxen (NAP) from NAP covalently coupled to human serum albumin or to mannosylated serum albumin and the metabolite naproxen-lysine. An assay for selective analysis of the different forms of NAP by direct plasma injection was developed with salicylate as internal standard and solute detection by laser-induced fluorescence. Compared with previously applied techniques, including HPLC and total plasma fluorescence, MECC offers the advantage that free and covalently bound NAP can be differentiated in one run and can be accurately monitored in microliter quantities of plasma. Summation of all NAP equivalents determined by MECC revealed data that compare well with those produced by total plasma fluorescence and HPLC. PMID- 9365393 TI - Intramuscular administration of 5 alpha-dihydrotestosterone heptanoate: changes in urinary hormone profile. AB - A recommended confirmatory procedure for detecting 5 alpha-dihydrotestosterone (DHT) doping in male athletes proposed the use of the urinary concentration ratio of DHT to epitestosterone (EpiT) as the primary marker and those of 5 alpha androstane-3 alpha,17 beta-diol (5 alpha-Adiol) to EpiT, luteinizing hormone (LH), and 5 beta-androstane-3 alpha,17 beta-diol (5 beta-Adiol) as secondary markers. Here we investigate the effects on these markers of intramuscular administration of DHT heptanoate (250 mg) to six healthy men. Within 24 h of administration all four markers greatly exceeded the published discrimination limits, remaining above these limits for 10-14 days. All ratios returned to basal values by day 28. In contrast to results after percutaneous administration, 5 beta-Adiol excretion decreased, probably as a consequence of greater suppression of testicular steroidogenesis. Results were largely in agreement with those obtained after percutaneous administration, although probably augmented by the larger dose and the different route of delivery. PMID- 9365394 TI - Clinical evaluation of Toxi.Prep: a semiautomated solid-phase extraction system for screening of drugs in urine. AB - A prototype Toxi.Prep (TP) system that utilizes solid-phase extraction (SPE) has been developed as a method for broad-spectrum drug screening and identification of tetrahydrocannabinol (THC) metabolites in urine. TP can simultaneously extract up to seven specimens while automating the process of sample extraction, washing, and elution onto a chromatogram. TP was compared with the Toxi. Lab A (TL-A) system for extraction of basic drugs only. In a blind study, 33 distinct drugs and metabolites were detected in 55 urines over 13 runs. Of the drug occurrences, 68.8% (141 of 205) were detected on both TP and TL-A. Of the 13 runs, quinidine and quinine, nortriptyline metabolites, and diphenhydramine were noted more frequently on TP than TL-A, whereas nicotine and metabolites, morphine, and methadone metabolites were more frequently noted on TL-A. Twenty specimens were analyzed for THC metabolites. Of the cases positive for THC metabolites, 100% (16 of 16) were positive by both methods. Time and motion studies for all runs proved an overall labor reduction for extraction and spotting by approximately 40%. PMID- 9365395 TI - Rapid diagnosis of MCAD deficiency: quantitative analysis of octanoylcarnitine and other acylcarnitines in newborn blood spots by tandem mass spectrometry. AB - We report the application of tandem mass spectrometry to prospective newborn screening for medium-chain acyl-CoA dehydrogenase (MCAD) deficiency. MCAD deficiency is diagnosed from dried blood spots on filter paper cards from newborns on the basis of the increase of medium chain length acylcarnitines identified by isotope dilution mass spectrometry methods. A robust and accurate semiautomated method for the analysis of medium chain length acylcarnitines as their butyl esters was developed and validated. Quantitative data from the analyses of 113 randomly collected filter paper blood spots from healthy newborns showed low concentrations of medium chain length acylcarnitines such as octanoylcarnitine. The maximum concentration of octanoylcarnitine was 0.22 mumol/L, with the majority being at or below the detection limit. In all 16 blood spots from newborns with confirmed MCAD deficiency, octanoylcarnitine was highly increased [median 8.4 mumol/L (range 3.1-28.3 mumol/L)], allowing easy detection. The concentration of octanoylcarnitine was significantly higher in these 16 newborns (< 3 days of age) than in 16 older patients (ages 8 days to 7 years) with MCAD deficiency (median 1.57 mumol/L, range 0.33-4.4). The combined experience of prospective newborn screening in Pennsylvania and North Carolina has shown a disease frequency for MCAD deficiency of 1 in 17,706. No false positive and no known false-negative results have been found. A validated method now exists for prospective newborn screening for MCAD deficiency. PMID- 9365396 TI - Quantification of c-erbB-2 gene expression in breast cancer by competitive RT PCR. AB - We adapted competitive reverse transcription-polymerase chain reaction (RT-PCR) for quantitative evaluation of c-erbB-2 expression in breast cancer. A fixed amount of cDNA target was coamplified with dilutions of a nonhomologous DNA sequence used as an internal standard (IS). The IS and the target shared the same primer sequences but yielded PCR products of different sizes (348 and 340 bp, respectively). A fluorescent sense primer was used so that the PCR products separated on denaturing polyacrylamide gels could be quantified with an automated DNA sequencer. In human breast cancer cell lines, c-erbB-2 expression was found to range from 0.151 to 652 zmol/microgram total RNA (i.e., 91 to 391,200 molecules/microgram total RNA; 1 zmol = 10(-3) amol), with the two highest values corresponding to the c-erbB-2 overexpressing cell lines MDA-MB-453 and SK-BR-3. In a series of 39 breast cancer biopsies, the concentrations ranged from 0.117 zmol/micrograms to 1.15 amol/microgram total RNA (i.e., 70 to 690,000 molecules/microgram total RNA). The c-erbB-2 oncoprotein (p185) was determined in 30 samples by an enzyme immunoassay. A close correlation was found between c-erbB 2 gene and oncoprotein expression (P = 0.0067). Thus, this competitive RT-PCR method appears to be a reliable way to evaluate the expression of c-erbB-2 in small tumor samples. PMID- 9365397 TI - Rapid detection of 21-hydroxylase deficiency mutations by allele-specific in vitro amplification and capillary zone electrophoresis. AB - A quick diagnosis of the classic form of 21-hydroxylase deficiency (simple virilizing and salt wasting) is of great importance, especially for prenatal diagnosis and treatment in pregnancies at risk. A method for simultaneous detection of common point mutations in the P450c21 B gene is here proposed by combining a nested PCR amplification refractory mutation system (ARMS) with capillary zone electrophoresis (CZE) in sieving liquid polymers. In the first PCR, B genes are selectively amplified. In the nested reaction, ARMS-detected wild-type and mutated alleles are separately pooled and resolved by CZE. CZE is performed in coated capillaries in the presence of 30 g/L hydroxyethyl cellulose in the background electrolyte for size separation of the DNA analytes. For high sensitivity detection the electrophoresis buffer contains the fluorescent dye SYBR Green I. Laser-induced fluorescence detection is obtained by excitation at 488 nm and signal collection at 520 nm. Specificity and reproducibility of the protocols were established by using samples from 75 Italian families with 21 hydroxylase deficiency already genotyped by allele-specific oligonucleotide hybridization or direct sequencing. Whereas dot-blot is time consuming because of the high number of hybridizations with radioactive probes, this present protocol is more rapid, giving sufficient separation on CZE after PCR reactions without preconcentration or desalting of samples. PMID- 9365398 TI - Fiber-optic immunosensor for measurement of myoglobin. AB - A self-contained fiber-optic immunosensor was developed to measure the 16,500-Da protein myoglobin. The sensing element was constructed by entrapment of Cascade Blue-labeled antibody within polyacrylamide gel at the distal face of an optical fiber 300 microns in core diameter. The polyacrylamide gel composition was optimized to allow diffusion of myoglobin but to exclude hemoglobin and higher molecular-mass proteins from the sensing area. The analytical signal was derived from fluorescence energy transfer between Cascade Blue and the heme group of myoglobin. Fluorescence quenching occurred when myoglobin bound to labeled antibody. The total amount of fluorescence quench was dependent on the antibody labeling conditions and the amount of antibody incorporated in the sensor gel matrix. Myoglobin concentrations > 5 nmol/L (83 micrograms/L) were measurable with response times of 15 to 130 min limited by diffusion into the sensing element. This report demonstrates the technical feasibility for a self-contained immunosensor to measure a protein analyte. PMID- 9365399 TI - Capillary isoelectric focusing and high-performance cation-exchange chromatography compared for qualitative and quantitative analysis of hemoglobin variants. AB - We have developed two assays for complete analysis of hemoglobins (Hbs) in the field of hemoglobinopathies: a high-performance cation-exchange liquid chromatography (HPLC) assay on the weak cation-exchanger Poly Cat A and a two step capillary isoelectric focusing (CIEF) assay on the neutral-coated capillary from Beckman in a narrow pH gradient. The resolution was satisfactory for both HPLC and CIEF and allowed separation of normal and common abnormal Hbs, i.e., Hb A, Hb F, Hb A2, Hb S, Hb C, and Hb E; slight differences were shown for the resolution of unusual variants such as Hb C-Harlem and Hb D-Punjab. The reproducibility of retention times was satisfactory as well for HPLC (CV 3.3%) and CIEF (CV 4.9%). The imprecision of quantification of Hb A2, evaluated at two concentrations, and of Hb F and Hb S was < 5%, except for low concentrations of Hb A2 quantified by CIEF. Quantitative data obtained for these three Hb forms were highly correlated between the two assays. These results suggest that the new CIEF assay can be competitive with HPLC for complete routine analysis of Hb variants. PMID- 9365400 TI - Thyroxine, thyrotropin, and age in a euthyroid hospital patient population. AB - The diagnosis of thyroid disease now often can be achieved reliably by measuring thyrotropin (TSH) alone. Thyroxine (T4), triiodothyronine, and other analytes are only needed if TSH and the accompanying clinical condition are discordant. We describe here work that confirms the age independence of TSH in both inpatient and outpatient euthyroid hospital populations between ages 20 and at least 80 years, and demonstrates that although free T4 does vary with age, the range of variation remains within the T4 reference interval. On this basis, TSH-based thyroid diagnostic algorithms can be used reliably in adults without reference to age-related reference intervals. PMID- 9365401 TI - Effect of analytical run length on quality-control (QC) performance and the QC planning process. AB - The performance measure traditionally used in the quality-control (QC) planning process is the probability of rejecting an analytical run when an out-of-control error condition exists. A shortcoming of this performance measure is that it doesn't allow comparison of QC strategies that define analytical runs differently. Accommodating different analytical run definitions is straightforward if QC performance is measured in terms of the average number of patient samples to error detection, or the average number of patient samples containing an analytical error that exceeds total allowable error. By using these performance measures to investigate the impact of different analytical run definitions on QC performance demonstrates that during routine QC monitoring, the length of the interval between QC tests can have a major influence on the expected number of unacceptable results produced during the existence of an out of-control error condition. PMID- 9365402 TI - Disappearance of human chorionic gonadotropin and its alpha- and beta-subunits after term pregnancy. AB - We have used high-specificity and precision immunofluorometric assays to measure the elimination half-times of human chorionic gonadotropin (hCG), hCG alpha, and hCG beta in serum over 21 days after delivery in six women with term pregnancies. Baseline concentrations and half-times were calculated with the use of a curve fitting algorithm for multiexponential decay. In contrast to the two-component model, a three-component exponential function with baseline provided a fit for which predicted values could not be distinguished from the observed values by analysis of variance. Median half-times were 3.6, 18.0, and 53.0 h for hCG; 1.0, 23.4, and 194 h for hCG beta; and 0.6, 6.2, and 21.9 h for hCG alpha. The mean ratio of hCG alpha to hCG decreased rapidly from 36.9% to 3.3% on day 3; thereafter it increased to 64.3% 21 days after delivery because of a higher baseline concentration of hCG alpha. hCG beta had the slowest total elimination rate, and the ratio of hCB beta to hCG in serum increased from 0.8% before delivery to 26.7% after 21 days. If the metabolism of hCG and hCG beta is similar in patients with trophoblastic disease, the ratio of hCG beta to hCG must be evaluated with caution in samples taken several days after initiating therapy. We conclude that the disappearance of hCG beta from plasma is slower than previously recognized and that the ratios of hCG beta or hCG alpha to intact hCG vary as a function of postpartum time. Such information may be important in clinical studies of pregnancy disorders. PMID- 9365403 TI - Comparison of NCEP performance specifications for triglycerides, HDL-, and LDL cholesterol with operating specifications based on NCEP clinical and analytical goals. AB - The National Cholesterol Education Program (NCEP) performance specifications for methods that measure triglycerides, HDL-cholesterol, and LDL-cholesterol have been evaluated by deriving operating specifications from the NCEP analytical total error requirements and the clinical requirements for interpretation of the tests. We determined the maximum imprecision and inaccuracy that would be allowable to control routine methods with commonly used single and multirule quality-control procedures having 2 and 4 control measurements per run, and then compared these estimates with the NCEP guidelines. The NCEP imprecision specifications meet the operating imprecision necessary to assure meeting the NCEP clinical quality requirements for triglycerides and HDL-cholesterol but not for LDL-cholesterol. More importantly, the NCEP imprecision specifications are not adequate to assure meeting the NCEP analytical total error requirements for any of these three tests. Our findings indicate that the NCEP recommendations fail to adequately consider the quality-control requirements necessary to detect medically important systematic errors. PMID- 9365404 TI - Comparison of mean normal prothrombin time (PT) with PT of fresh normal pooled plasma or of a lyophilized control plasma (R82A) as denominator to express PT results: collaborative study of the International Federation of Clinical Chemistry. IFCC Working Group Standardization of Coagulation Tests. AB - The mean normal prothrombin time (MNPT) is currently recommended as the denominator term in the expression of PT ratio or International Normalized Ratio (INR) values. The PT of lyophilized normal control plasmas might also be used in calculating PT ratios, but the overall accuracy of this approach and its dependence on reagents and endpoint detectors have not been evaluated in detail. In an IFCC collaborative study involving 15 expert laboratories and 58 PT systems, the PT ratios of 30 apparently healthy subjects were expressed with the use of the MNPT, the PT of fresh normal pooled plasma (FNPP) obtained from the same apparently healthy subjects, or the PT of plasma R82A--a lyophilized normal pooled plasma prepared by the Verband der Deutschen Gerate-Hersteller for in house calibration of a large amount of control plasma--as the denominator term. The total imprecision of the PT of plasma R82A averaged 2.16%. Mean PT ratios did not differ from 1.00 (mean 1.00, range 1.00-1.01) with the use of the MNPT as the denominator term. Mean PT ratios were > 1.00 with the FNPP-PT as the denominator term (1.02, 0.96-1.05), and differed according to endpoint detectors (P = 0.024). Mean PT ratios with plasma R82A-PT as the denominator term averaged 0.98 (range 0.91-1.06) with plain thromboplastins (n = 11), 1.02 (0.98-1.06) with combined thromboplastins (n = 3), and 0.93 (0.87-0.97) with recombinant thromboplastins (n = 2), but they differed according to the brand of plain or recombinant reagents (P = 0.00001), the endpoint detector (P < 0.0025), and the plasma citrate concentration (P < 0.0025). These findings underline the differences in the PT of lyophilized plasma R82A and the MNPT and PT of FNPP obtained from the same individuals and support the recommendation that the system-specific MNPT should be used as the ideal index of the normal PT in the calculation of INR values. PMID- 9365405 TI - Biological variation of International Normalized Ratio for prothrombin times, and consequences in monitoring oral anticoagulant therapy: computer simulation of serial measurements with goal-setting for analytical quality. AB - Oral anticoagulant therapy (OAT) has a well-established efficacy in prophylaxis and treatment of thromboembolic disorders. Because complications are related to intensity of OAT, optimal control of treatment is mandatory. In studies of OAT, as many as 30% of International Normalized Ratio (INR) measurements for prothrombin times fall outside the therapeutic interval. Preanalytical, analytical, and biological variation all contribute to this. Computer simulations of serial INR measurements were performed for various assumed in-treatment setpoints within the therapeutic interval INR 2.0-3.0 and for an "in-treatment within-subject variation" (CV) of 10.1%. Results are presented in difference plots with therapeutic intervals and critical differences. If the in-treatment setpoint is mid-interval (INR = 2.5), only 5% of simulated INR values fall outside the therapeutic interval. Setpoints deviating from the mid-interval and increases in the in-treatment within-subject variation considerably increase the number of observations outside the therapeutic interval and the critical differences. In conclusion, random variation, biological or analytical, and setpoints (targets) deviating from mid-interval explain a substantial number of the INR values outside therapeutic intervals observed in clinical studies. Analytical imprecision should be kept < 5% and analytical bias < +/- 0.2 INR. PMID- 9365407 TI - Rapid detection of the fibrinogen A alpha 16Arg --> His mutation. PMID- 9365406 TI - Use of the Friedewald formula to estimate LDL-cholesterol in patients with chronic renal failure on dialysis. PMID- 9365408 TI - Urine pyridinium cross-links determinations by Beckman Cross Links Kit. PMID- 9365409 TI - Convenient, rapid test for lead in blood with use of disposable electrodes. PMID- 9365410 TI - Improved therapeutic drug monitoring of tacrolimus (FK506) by tandem mass spectrometry. PMID- 9365411 TI - Optimization of nonisotopic PCR-single-strand conformation polymorphism analysis. PMID- 9365412 TI - Low concentrations of folate in serum and erythrocytes of smokers: methionine loading decreases folate concentrations in serum of smokers and nonsmokers. PMID- 9365413 TI - Rapid identification of angiotensin-converting enzyme genotypes by capillary electrophoresis. PMID- 9365414 TI - Very long chain fatty acid analysis of dried blood spots on filter paper to screen for adrenoleukodystrophy. PMID- 9365415 TI - Serum concentrations of interleukin-6 are increased when sampled through an indwelling venous catheter. PMID- 9365416 TI - Interference of anthracycline derivatives with measurement of proteins with BCA. PMID- 9365417 TI - Stability of a control material suitable for quantitative measurement of urine myoglobin. PMID- 9365418 TI - Rapid identification of HLA DQA1*0501, DQB1*0201 and DRB1*04 alleles in celiac disease by a PCR-based methodology. PMID- 9365419 TI - Model for establishing biological variation in non-healthy situations: renal posttransplantation data. PMID- 9365420 TI - Concurrent determination of second-generation anti-depressants in plasma by using gas chromatography with nitrogen-phosphorus detection. PMID- 9365422 TI - Esophageal cancer. PMID- 9365421 TI - Injury by electrical forces: pathophysiology, manifestations, and therapy. AB - The pathogenesis and pathophysiologic features of electrical injury are more complex than once thought. The relative contributions of thermal and pure electrical damage depend on the duration of electric current passage, the orientation of the cells in the current path, their location, and other factors. If the contact time is brief, nonthermal mechanisms of cell damage will be most important and the damage is relatively restricted to the cell membrane. When contact time is much longer, however, heat damage predominates and the whole cell is affected directly. These parameters also determine the anatomic tissue distribution of injury. Damage by Joule heating is not known to be dependent on cell size, whereas larger cells are more vulnerable to membrane breakdown by electroporation. Cells do survive transient plasma membrane rupture under appropriate circumstances or if therapy is instituted quickly. If membrane permeabilization is the primary cellular pathologic condition, then injured tissue may be salvageable and the challenge for the future is to identify a technique to reseal the damaged membranes promptly. Present standards of care for electrical injury require a fully staffed and well-equipped intensive care unit, available operating suites, and the availability of the full range of medical specialists. Major teaching hospitals with burn centers may be the ideal setting for the treatment of an electrical trauma victim. After the initial resuscitation, efforts are directed primarily towards preventing additional tissue loss mediated through the compartment syndrome, compressive neuropathies, or the presence of necrotic tissue. Renal and cardiac failure caused by the release of intracellular muscle contents into the circulation must be prevented. Attention can then be directed towards maximizing tissue salvage and preventing late skeletal and neuromuscular complications. Reconstructive procedures that transfer healthy tissue from a distance are necessary to optimize the functional value of the remaining tissue. Finally, unless the patient is rehabilitated psychologically, the real benefit from other sophisticated care will not be fully realized. These goals are important throughout the acute care of the patient. In the future, new guidelines for treating electrical trauma will be based on a clearer understanding of the relevant pathophysiologic features. These strategies will rely on improved diagnostic imaging and on reversing the fundamental problem of cell membrane damage. Moreover, complex biochemical and organ system pathophysiologic interactions will require careful management. If successful, research efforts presently underway should improve the prognosis of victims after electrical trauma. PMID- 9365423 TI - Sites of action of gamma-hydroxybutyrate (GHB)--a neuroactive drug with abuse potential. AB - OBJECTIVE: This review highlights the biochemistry, pharmacology, and toxicology of the naturally-occurring fatty acid derivative, gamma-hydroxybutyrate (GHB). GHB is derived from gamma-aminobutyric acid (GABA) and is proposed to function as an inhibitory chemical transmitter in the central nervous system. CONTENT: When administered in pharmacological doses, its powerful central nervous system depressant effects are readily observed. Although some of the neurophysiological actions of GHB could involve alterations in dopaminergic transmission in the basal ganglia, both its physiological and pharmacological actions are probably mediated through specific brain receptors for GHB. In addition, GHB might mediate some of its effects through interaction with the GABA(B) receptor. Experimentally, GHB has been used as a model for petit mal epilepsy; clinically, it has been used as a general anesthetic and as a drug to treat certain sleep disorders and related conditions. Owing to the purported ability of GHB to induce a state of euphoria, recreational use of this substance is popular. Although no deaths or long-term problems have been associated with GHB abuse, symptoms of GHB intoxication can be severe. The continued potential for GHB abuse makes it imperative for clinical toxicologists to be aware of the effects of this agent. Future research on the mechanism of action of GHB is needed to elucidate both its central nervous system depressant properties and its ability to effect a state of well-being. PMID- 9365424 TI - A sudden awakening from a near coma after combined intake of gamma-hydroxybutyric acid (GHB) and ethanol. AB - OBJECTIVE: A case of a sudden awakening from a near coma after combined intake or gamma-hydroxybutyric acid (GHB) (125 micrograms/mL), ethanol (134 mg/dL), and cannabinoids is described. METHODS: GHB was determined by gas chromatography-mass spectrometry after acetonitrile precipitation and derivation with N-methyl-N trimethylsilyltrifluoroacetamide, using valproic acid as the internal standard. CONCLUSION: The described case illustrates the consequences of GHB overdose. GHB overdose should be considered in every case of unexplained sudden coma, i.e., without any evidence of head injury, intake of coma-inducing drugs, or increasing intracranial pressure. GHB overdose will be missed by routine toxicological screening. PMID- 9365426 TI - Pharmaceutical drug abuse in children. PMID- 9365425 TI - Chemical submission: GHB, benzodiazepines, and other knock out drops. PMID- 9365427 TI - Methods used to decrease lithium absorption or enhance elimination. AB - OBJECTIVE: To review current methods, well documented and investigational, being used to decrease lithium absorption or enhance lithium elimination. METHODS: The basic science and clinical literature on lithium were reviewed by a comprehensive Medline search from 1984 to 1996. Additional references were identified by reviewing the reference citations from the results of the Medline search. RESULTS: Prevention of Absorption: Whole bowel irrigation has been demonstrated to be an effective means of enhancing lithium removal from the gastrointestinal tract. Sodium polystyrene sulfonate resin administration has been shown to be effective in binding lithium elimination in animal and human models. However, the lower limits of effective sodium polystyrene sulfonate dosing and the extent of potassium lowering in humans are questions that need to be answered before sodium polystyrene sulfonate resin can be recommended for routine, use. Enhancement of Elimination: Saline or forced diuresis is not effective in enhancing lithium elimination unless the patient is volume or sodium depleted. The use of continuous arteriovenous hemodiafiltration or low dose dopamine to enhance lithium elimination has only been documented in case reports. Intravenous aminophylline (theophylline) is not consistently effective and its risks outweigh possible benefits. The literature supports hemodialysis as a well documented and effective means of enhancing lithium elimination. Controversy exists over the appropriate indications for its initiation. DISCUSSION: Given the wide interpatient variability in lithium pharmacokinetics, single case reports do not provide sufficient evidence of the effectiveness of a given method to enhance PMID- 9365428 TI - Efficacy of ipecac during the first hour after drug ingestion in human volunteers. AB - OBJECTIVE: To determine the decrease of drug absorption when syrup of ipecac is administered at various times within one hour of drug ingestion. METHODS: Ten healthy human volunteers were recruited for a four-limbed randomized crossover study. The three experimental limbs consisted of administration of 30 mL syrup of ipecac, at 5, 30, or 60 minutes after ingestion of 3900 mg acetaminophen as 12 x 325 mg tablets with 250 mL room temperature water. The fourth limb served as control. Blood samples were drawn at 0, 0.5, 1.0, 2.0, 3.0, 4.0, 6.0, and 8.0 hours after analgesic ingestion for serum acetaminophen concentration determination by high-performance liquid chromatography. Repeated measures ANOVA and Tukey's HSD tests were used for group comparisons. RESULTS: The area under the serum concentration vs time curve was (mean +/- SD) 206 +/- 48, 67 +/- 37, 183 +/- 78, and 162 +/- 47 mg/L for control, 5, 30, and 60 minutes, respectively. This corresponds to decreases in bioavailability of 67, 11, and 21%. Only the 5 minute group differed significantly from control (p < 0.05). Sedation was observed as a significant adverse effect of ipecac administration. CONCLUSIONS: Our data do not support benefit from ipecac administration at 30 minutes and beyond. Our data suggest that benefit is lost at some point between 5 and 30 minutes. The sedative effect of ipecac may confound the observation of patients who have ingested sedative hypnotic agents. PMID- 9365429 TI - Toxicokinetics of acute strychnine poisoning. AB - BACKGROUND: Strychnine competes with the inhibitory neurotransmitter glycine producing an excitatory state characterized clinically by hyperreflexia, severe muscle spasms, and convulsions. However, the kinetics after overdose have not been well described. CASE REPORT: A 34 year-old male presented to the emergency department 20 minus after ingesting half of a 250-mL container of 2% strychnine sulfate (2.25 g). The reported lethal dose is 100-120 mg. He was alert and oriented and experiencing muscle spasms. His condition deteriorated prompting sedation, muscle paralysis, and tracheal intubation. He was given activated charcoal 100 g per nasogastric tube. He was admitted to intensive care where he was managed with diazepam, pentobarbital, and pancuronium. Despite mild rhabdomyolysis, he recovered and was extubated on day three. Although receiving prophylactic heparin therapy, a massive fatal pulmonary embolus ensued. Eighteen blood specimens for strychnine analysis were obtained from 20 minutes to 51 hours after ingestion. Serum concentrations were determined with gas chromatography mass spectroscopy. Disappearance followed a first-order process with a t 1/2 of 16 hours (r, = 0.97). DISCUSSION: Our results confirm the findings of an earlier case report of 19 strychnine levels obtained between 4 and 19 hours which described first-order kinetics with a similar t 1/2 of 10 hours. CONCLUSION: Strychnine disappearance in this overdose was well described by a first-order process with a t 1/2 of 10-16 hours. PMID- 9365430 TI - A fatal overdose of arginine hydrochloride. AB - CASE REPORT: Arginine hydrochloride is used both diagnostically to test for growth hormone deficiency and therapeutically for treatment of metabolic alkalosis. We describe a 21-month-old girl who developed cardiopulmonary arrest following an accidental overdose of arginine hydrochloride. The patient developed acute metabolic acidosis and transient, but severe, hyponatremia. Thirty-six hours after successful resuscitation, she developed fatal central pontine and extrapontine myelinolysis. Unlike previous reports of arginine-toxicity, our patient showed no evidence of hyperkalemia. This case illustrates a previously unreported mechanism of arginine hydrochloride toxicity. PMID- 9365431 TI - Viral encephalitis masquerading as a fulminant anticholinergic toxidrome. AB - CASE REPORT: Emergency physicians are well versed in the recognition and management of certain poisonings which present with characteristic toxidromes. We present a case of a young pharmacy student who presented with altered mental status, tachycardia, facial flushing, dilated pupils, and dry skin and mucous membranes presumably due to anticholinergic poisoning. She improved with a combination of benzodiazepines and the acetylcholinesterase inhibitor physostigmine. However, following resolution of her initial symptoms, she became ill again and the subsequent neurologic evaluation revealed a diencephalic lesion consistent with a viral encephalitis. The acute anticholinergic signs and symptoms resulted from this lesion in an area of large cholinergic outflow. Although recognition and management of her acute anticholinergic findings were appropriate, they were not the manifestations of an acute anticholinergic ingestion. PMID- 9365432 TI - Euro bleach: fatal hypernatremia due to 13.3% sodium hypochlorite. PMID- 9365433 TI - Efficacy of two commercial products for altering urine drug test results. AB - OBJECTIVE: We have become aware of several commercial products that, when orally ingested, will purportedly not only eliminate "toxins" from a person's system, but will also correct any urinary imbalances caused by excessive water consumption. METHOD: Unblinded study of one volunteer subject, tested weekly x 4 for 24-hour urine elimination of test drug under conditions of control, control plus 1200 mL water, Quick Flush', and Eliminator. RESULTS: Each of the treatment protocols studied caused reductions of drug or metabolite concentrations as measured by gas chromatography-mass spectrometry in urine specimens collected up to 24 hours after ingestion of amphetamine, 9-carboxy-11-nor-delta-9-THC, benzoylecgonine, or codeine, yet the radioimmunoassay screening results demonstrated very little effect. Water alone was approximately as effective as the two commercial products in reducing the metabolite level. None of the treatment protocols employed in this study altered urinary pH, specific gravity, or creatinine concentration outside the normally accepted physiological range. CONCLUSIONS: Attempts to conceal drug abuse by water dilution are most likely to play a substantial role when concentrations are at or near the detection threshold for a particular assay such as the terminal stages of drug eliminations. PMID- 9365435 TI - Serum aluminium levels of workers in the bauxite mines. AB - BACKGROUND/OBJECTIVE: Aluminium is produced from the mineral bauxite. Occupational exposure is reported during the industrial processing of aluminium and is associated with pulmonary and neurotoxicity. However, data on exposure and toxicity of workers in the open bauxite mining industry do not exist. Therefore, a study was performed to explore aluminium exposure in employees involved in this bauxite mining process in a Surinam mine. METHODS/DESIGN: A group of workers occupationally exposed to aluminium in an open bauxite mine were compared with a group of nonexposed wood processors. Serum aluminium was analyzed using atomic absorption spectrometry Data from the clinical chemistry of the blood and a questionnaire were used to explore determinants for aluminium exposure. RESULTS: No significant difference between serum aluminium in the exposed (4.4 +/- 2.0 micrograms/L, n = 27) and control group (5.1 +/- 1.5 micrograms/L, n = 27) was detected. For the serum concentration of the clinical chemical variables (calcium, citrate, and creatinine), a statistically significant difference was computed (p < or = 0.02) between the exposed and control group. All levels were slightly higher in the exposed group; no statistically significant correlations with serum aluminium were found. CONCLUSIONS: In this study, serum aluminium values were in the normal range, no significant difference between the groups could be detected despite long-term occupational exposure. PMID- 9365434 TI - Breath and blood ethanol following use of a cough-cold preparation. PMID- 9365436 TI - Urinary mercury in twelve cases of cutaneous mercurous chloride (calomel) exposure: effect of sodium 2,3-dimercaptopropane-1-sulfonate (DMPS) therapy. AB - OBJECTIVE: To evaluate clinical symptoms and urinary mercury before and after chelation therapy in subjects with chronic cutaneous mercurous chloride (HgCl; calomel) exposure. SUBJECTS: Twelve women from 19-45 years who had used a facial cream which contained HgCl (5.9%) for 2 to 10 years. DESIGN: Twenty-four hour urine samples were collected for basal urine mercury. All the subjects received a 5-day cycle of oral sodium 2,3 dimercaptopropane-l-sulfonate (Dimaval capsules 100 mg) 200 mg/d on an outpatient basis. The urine mercury excretion was monitored 24 hours after the first dose and 72 hours after the last dose in eight subjects. RESULT: Exanthem and tremor were detected in two of 12 subjects. The range of urine mercury was 180 to 1876 micrograms/g creatinine. A significant increase in the urinary mercury excretion was observed in the first 24 hours after beginning sodium 2,3-dimercaptopropane-1-sulfonate. CONCLUSION: Chronic topical application of 5.9% HgCl cream was associated with clinical mercurialism in two subjects and with high urinary mercury level in all the cases. Sodium 2,3 dimercaptopropane-1-sulfonate was effective in increasing urine mercury. PMID- 9365437 TI - Elevated blood mercury following the ingestion of mercurochrome. PMID- 9365438 TI - Case series of Thermopsis exposures. AB - BACKGROUND: Thermopsis species have been suspected of causing livestock losses. One human case series of Thermopsis poisoning was located in the literature. We report 23 suspected cases of Thermopsis exposures, some resulting in significant toxicity.. METHODS: Retrospective chart review of all calls involving "buffalo beans" received by the Regional Poison Centre from 1990-1995. RESULTS: There was a total of 23 exposures, 21 of which involved children < 12 years of age. Amounts ingested varied as did the plant part ingested. Eighteen of the patients developed symptoms within a few hours and symptoms lasted up to 12 hours. Symptoms included vomiting (14), dizziness (5), abdominal pain (3), drowsiness (2), nausea (2), headache (1), oral irritation (1), tachycardia (1), tremors (1), and other general signs (3). Of the 23 cases, 15 were managed at home but eight were referred to a health care facility, with two requiring admission. In one of the admissions, laboratory data revealed an elevated creatine kinase which remained elevated for 48 hours. Management was symptomatic and included decontamination, fluids, and observation. Plants were not professionally identified, but were referred to by the name "buffalo bean" or "buffalo pea." However, in some cases, relying on the name "buffalo bean" lead to misidentification of the plant and possible underestimation of toxicity. CONCLUSION: Ingestion of Thermopsis can be associated with significant morbidity. Gastric lavage may be of value in large ingestions prior to symptoms but effectiveness of activated charcoal is questionable. Patients should be observed for several hours for symptoms and supportive treatment instituted as required. PMID- 9365439 TI - Acute oleander poisoning after a self-prepared tisane. PMID- 9365441 TI - Around the corner from the backstreets. PMID- 9365440 TI - Unintentional childhood poisoning in athens: a mirror of consumerism? AB - OBJECTIVE: To estimate the incidence of unintentional childhood injuries resulting from accidental poisonings in the Greater Athens area and to ascertain what fraction of this incidence could be linked to specified conditions, amenable to preventive interventions. METHODS: Prospective study over 12 months of 670 children hospitalized 224 hours for accidental poisoning. Site: Two pediatric hospitals and three smaller units in Greater Athens admitting children < or = 15 years old. Information was recorded in a semistructured questionnaire and the data were analyzed through simple stratification by one or more variables. Results Accidental poisoning requiring hospitalization > or = 24 hours was 50% higher among boys than among girls, peaked towards the end of the second year, and declined sharply after the fourth year of life with an estimated incidence of 500 cases per 100,000 among children > or = 5 years old. Cigarettes were the most common agent among infants, whereas medicinal products dominated all other childhood periods. Detergents, petroleum products, and pesticides each contributed about 10% of all poisonings with detergents peaking during the second year of life, petroleum products during the third year, and pesticides remaining constant, in proportional terms, throughout childhood. During the working hours of the day the incidence of poisonings was 80% higher than during the late afternoon and evening hours or the weekends, the times when both parents are usually at home; the excess was statistically significant. The presence of both parents at home in the afternoon hours was associated with an almost 50% reduction of hospitalized poisoning. The accessibility of products with poisoning potential was of major importance. Some specific conditions that led to the incident included storage of potentially poisoning products in the refrigerator, storage of such products in containers of innocuous products, without proper labeling, and parental errors in medication. CONCLUSIONS: Unintentional childhood poisoning further reflects an interaction between inappropriate storage of consumer products and suboptimal supervision during the housekeeping hours of the day. PMID- 9365442 TI - Sentinel lymph-node biopsy in melanoma: is less surgery better? PMID- 9365443 TI - Cervical adenocarcinoma in situ: a persistent clinical dilemma. PMID- 9365444 TI - Phantom limb pain. PMID- 9365445 TI - Calcium-channel blockers in the management of preterm labour. PMID- 9365446 TI - A tale of two worlds in prescribing etidronate for osteoporosis. PMID- 9365447 TI - Short-term improvements in public health from global-climate policies on fossil fuel combustion: an interim report. Working Group on Public Health and Fossil Fuel Combustion. AB - BACKGROUND: Most public-health assessments of climate-control policies have focused on long-term impacts of global change. Our interdisciplinary working group assesses likely short-term impacts on public health. METHODS: We combined models of energy consumption, carbon emissions, and associated atmospheric particulate-matter (PM) concentration under two different forecasts: business-as usual (BAU); and a hypothetical climate-policy scenario, where developed and developing countries undertake significant reductions in carbon emissions. FINDINGS: We predict that by 2020, 700,000 avoidable deaths (90% CI 385,000 1,034,000) will occur annually as a result of additional PM exposure under the BAU forecasts when compared with the climate-policy scenario. From 2000 to 2020, the cumulative impact on public health related to the difference in PM exposure could total 8 million deaths globally (90% CI 4.4-11.9 million). In the USA alone, the avoidable number of annual deaths from PM exposure in 2020 (without climate-change-control policy) would equal in magnitude deaths associated with human immunodeficiency diseases or all liver diseases in 1995. INTERPRETATION: The mortality estimates are indicative of the magnitude of the likely health benefits of the climate-policy scenario examined and are not precise predictions of avoidable deaths. While characterized by considerable uncertainty, the short term public-health impacts of reduced PM exposures associated with greenhouse-gas reductions are likely to be substantial even under the most conservative set of assumptions. PMID- 9365448 TI - Value of natriuretic peptides in assessment of patients with possible new heart failure in primary care. AB - BACKGROUND: The reliability of a clinical diagnosis of heart failure in primary care is poor. Concentrations of natriuretic peptides are high in heart failure. This population-based study examined the predictive value of natriuretic peptides in patients with a new primary-care diagnosis of heart failure. METHODS: Concentrations of plasma atrial (ANP and N-terminal ANP) and B-type (BNP) natriuretic peptides were measured by radioimmunoassay in 122 consecutive patients referred to a rapid-access heart-failure clinic with a new primary-care diagnosis of heart failure. On the basis of clinical assessment, chest radiography, and transthoracic echocardiography, a panel of three cardiologists decided that 35 (29%) patients met the case definition for new heart failure. ANP and NT-ANP results were available for 117 patients (34 with heart failure) and BNP results for 106 (29 with heart failure). FINDINGS: Geometric mean concentrations of natriuretic peptides were much higher in patients with heart failure than in those with other diagnoses (29.2 vs 12.4 pmol/L for ANP; 63.9 vs 13.9 pmol/L for BNP; 1187 vs 410.6 pmol/L for NT-ANP; all p < 0.001). At cut-off values chosen to give negative predictive values for heart failure of 98% (ANP > or = 18.1 pmol/L, NT-ANP > or = 537.6 pmol/L, BNP > or = 22.2 pmol/L), the sensitivity, specificity, and positive predictive value for ANP were 97%, 72%, and 55%; for NT-ANP 97%, 66%, and 54%; and for BNP 97%, 84%, and 70%. Addition of ANP or NT-ANP concentration or both did not improve the predictive power of a logistic regression model containing BNP concentration alone. INTERPRETATION: In patients with symptoms suspected by a general practitioner to be due to heart failure, plasma BNP concentration seems to be a useful indicator of which patients are likely to have heart failure and require further clinical assessment. PMID- 9365450 TI - Randomised trial of oral morphine for painful episodes of sickle-cell disease in children. AB - BACKGROUND: Oral controlled-release morphine can provide effective analgesia through a non-invasive route and may facilitate outpatient management of severe episodes of sickle-cell pain. We compared the clinical efficacy and safety of oral morphine with continuous intravenous morphine in children with severe episodes of sickle-cell pain, by a double-blind, randomised, parallel-group design. METHODS: 56 children aged 5-17 years received loading doses of intravenous morphine of up to 0.15 mg/kg, followed by randomly assigned oral morphine 1.9 mg/kg every 12 h plus intravenous placebo (saline), or intravenous morphine 0.04 mg kg-1 h-1, plus placebo tablet. Breakthrough pain was treated with oral, immediate-release morphine 0.4 mg/kg every 2-3 h as required. Pain was assessed daily at 0900 h, 1300 h, 1700 h, and 2100 h with a picture face scale, a pictorial scale (Oucher), a behavioural-observational scale (CHEOPS), and by an investigator. FINDINGS: 50 children completed the study (28 boys, 22 girls; mean age 11.2 years [SD 3.5]; mean oral morphine dose 2.99 mg/kg daily [0.75]; mean intravenous morphine dose, 0.81 mg/kg daily [0.30]). Mean overall pain scores were similar for oral and intravenous morphine (CHEOPS, 6.3 [1.5] vs 6.4 [1.4], p = 0.8; Oucher, 31.5 [25.4] vs 39.2 [21.7], p = 0.3; Faces, 2.2 [1.4] vs 2.4 [1.3], p = 0.6; clinical rating, 1.7 [0.7] vs 1.9 [0.5], p = 0.3). Opioid analgesia was required for a mean of 4.2 days (1.7) and 5.4 days (2.6), respectively (p = 0.0591). Pain scores from all scales correlated significantly (r = 0.5865-0.8980, p = 0.0001). Frequency of rescue analgesia did not differ significantly between the oral and intravenous morphine groups (0.7 [0.8] vs 0.9 [0.7] doses daily, p = 0.2). Frequency and severity of adverse events did not differ significantly. INTERPRETATION: Oral, controlled-release morphine is a reliable, non-invasive alternative to continuous intravenous morphine for the management of painful episodes of sickle-cell disease in children. PMID- 9365449 TI - Randomised trial of epidural bupivacaine and morphine in prevention of stump and phantom pain in lower-limb amputation. AB - BACKGROUND: Epidural analgesia before limb amputation is commonly used to reduce postamputation pain. But there have been no controlled studies with large numbers of patients to prove such a pre-emptive effect. We investigated whether postamputation stump and phantom pain in the first year is reduced by preoperative epidural blockade with bupivacaine and morphine. METHODS: In a randomised, double-blind trial, 60 patients scheduled for lower-limb amputation were randomly assigned epidural bupivacaine (0.25% 4-7 mL/h) and morphine (0.16 0.28 mg/h) for 18 h before and during the operation (29 patients; blockade group) or epidural saline (4-7 mL/h) and oral or intramuscular morphine (31 patients; control group). All patients had general anaesthesia for the amputation and were asked about stump and phantom pain after 1 week and then after 3, 6, and 12 months by two independent examiners. Study endpoints were rate of stump and phantom pain, intensity of stump and phantom pain, and consumption of opioids. FINDINGS: Two patients in each group were withdrawn before amputation. The groups were well matched in baseline characteristics. Median duration of preoperative saline treatment was 18.5 h (IQR 17-20). Median duration of preoperative epidural blockade in the blockade group was 18 h (15-20.3). The combined median duration of postoperative epidural pain treatment in both groups was 166 h (89.3-308.3). After 1 week, 14 (52%) patients in the blockade group and 15 (56%) in the control group had phantom pain (95% CI - 30.6 to 22.7, p = 0.9). The figures for blockade versus control group were: 14 (82%) vs ten (50%; 4.0 to 60.8, p = 0.09) at 3 months; 13 (81%) vs 11 (55%; -2.7 to 55.3, p = 0.2) at 6 months; and nine (75%) vs 11 (69%; -27.0 to 39.6, p = 1.0) at 12 months. Intensity of stump and phantom pain and consumption of opioids were similar in both groups at all four postoperative interviews. INTERPRETATION: Perioperative epidural blockade started a median of 18 h (15-20.3) before the amputation and continued into the postoperative period does not prevent phantom or stump pain. PMID- 9365452 TI - Non-invasive diagnosis of Pneumocystis carinii pneumonia by PCR on oral washes. PMID- 9365451 TI - A clue in the duodenum. PMID- 9365453 TI - Treatment of classic Kaposi's sarcoma with liposomal encapsulated doxorubicin. PMID- 9365454 TI - No measles in Finland. PMID- 9365455 TI - Pioglitazone-reduced insulin resistance in patient with Werner syndrome. PMID- 9365456 TI - Losartan-associated atypical cutaneous lymphoid hyperplasia. PMID- 9365457 TI - Neonatal shivering and hypothermia after intrapartum amnioinfusion. PMID- 9365458 TI - Can intracranial pressure be measured non-invasively? PMID- 9365459 TI - Alzheimer's disease and DLST genotype. PMID- 9365460 TI - Frequency of intron 8 CFTR polythymidine sequence variant in neonatal blood specimens. PMID- 9365461 TI - Is control at work the key to socioeconomic gradients in mortality? PMID- 9365462 TI - Prevalence of coeliac disease in Northern Ireland. PMID- 9365463 TI - Transmission of HIV-1 and HBV [corrected] by head-butting. PMID- 9365464 TI - HIV case shocks USA. PMID- 9365465 TI - Chronic pancreatitis. PMID- 9365466 TI - Influence of disease burden, public perception, and other factors on new vaccine development, implementation, and continued use. AB - The development, implementation, and continued use of new vaccines depends on several factors. Although disease burden seems like an obvious quantitative measure for setting priorities for new vaccine development and use, resources are not always allocated proportionately. This is particularly evident for diseases that are unique (or largely limited) to people in developing countries. Public pressure based on perceptions of the risks associated with a disease or vaccine, the cost of new vaccines, and the ability to incorporate them into existing vaccination programmes also need to be considered in the decision to introduce new vaccines. Vaccine manufacturers play an important part in development of new vaccines, and therefore, the issues that are important to them, namely, production, intellectual property rights, and product liability, must be addressed. By advocating rational decisions, supported by accurate information, scientists and public-health professionals can have an important role in transforming the potential of new vaccines into the reality of new vaccine preventable diseases. PMID- 9365467 TI - The three-salesmen conundrum in medicine. PMID- 9365468 TI - Police brutality in the USA. PMID- 9365470 TI - Nurses at risk. PMID- 9365469 TI - Health effects of child labour. PMID- 9365471 TI - Randomised trial of fibrin glue versus polidocanol for bleeding peptic ulcer. PMID- 9365473 TI - Provision of intensive care in the UK. PMID- 9365472 TI - Randomised trial of fibrin glue versus polidocanol for bleeding peptic ulcer. PMID- 9365474 TI - Limbic selectivity of clozapine. PMID- 9365475 TI - Cardiac rehabilitation. PMID- 9365476 TI - Cardiac rehabilitation. PMID- 9365477 TI - Fever of unknown origin. PMID- 9365479 TI - Absence of relation between hyponatraemia and hypothyroidism. PMID- 9365478 TI - Intubation during cardiorespiratory arrest. PMID- 9365480 TI - Driving and stroke. PMID- 9365481 TI - Genetic anticipation: fact or artifact, genetics or epigenetics? PMID- 9365483 TI - Contribution of job control to social gradient in coronary heart disease. PMID- 9365482 TI - Molecular evidence for tuberculosis in an ancient Egyptian mummy. PMID- 9365484 TI - Triple-combination antiretroviral therapy in sub-Saharan Africa. PMID- 9365485 TI - "Underpowered" trials. PMID- 9365487 TI - [Ectopic ACTH secretion: a heterogeneous entity]. AB - OBJECTIVES: ACTH-secreting non-pituitary tumors are a rare cause of Cushing's disease. We report the clinical course, prognostic aspects and molecular analysis data in three patients for whom the diagnosis was confirmed but who had variable clinical features and laboratory results. CASE REPORTS: Patient n degree 1 had severe hypercorticism which rapidly progressed to death 13 months after diagnosis. In patient n degree 2, signs of hypercorticism severe, leading to death 5 years after discovery of the causal carcinoid tumor. Patient n degree 3 had moderate hypercorticism and has survived for more than 25 years. DISCUSSION: These 3 ectopic tumors are representative examples of a wide range of possible ACTH-secreting ectopic tumors. In highly malignant poorly-differentiated tumors such as small-cell anaplastic carcinomas, ACTH production is aberrant and poorly controlled, and thus not particularly effective. At the other extreme, typical benign bronchial carcinomas have a high degree of neuroendocrine differentiation and secrete ACTH in a well-controlled manner difficult to distinguish from corticotropic adenomas, further exaggerating the diagnostic pitfalls. PMID- 9365486 TI - [Benefits of early nephrological management in chronic renal failure]. AB - OBJECTIVES: We evaluated whether early nephrological referral of patients with chronic renal failure (CRF) resulted in improved condition of patients at initiation of maintenance dialysis and in better outcome on dialysis. PATIENTS AND METHODS: We prospectively recorded clinical status, laboratory parameters, length of hospital stay and outcome of 900 CRF patients who started maintenance dialysis at Necker hospital between January 1989 and December 1996. We compared patients who benefited regular nephrological follow-up, and patients who were referred in emergency conditions at the ultimate stage of CRF. RESULTS: Among the 900 patients, 731 (81.2%) had regular nephrological follow-up, including 632 (70.2%, group IA) with optimal preparation to dialysis and 99 (11%, group IB) whose clinical course was complicated due to heavy comorbidity, whereas 169 (18.8%, group II) had no previous nephrological management. Over the 8-year observation period, the proportion of the latter group did not decrease. Late referred patients had higher blood pressure level, more frequent fluid overload, higher serum levels of urea, creatinine, uric acid and phosphate, and lower levels of bicarbonate, calcium, albumin and creatinine clearance that did well prepared patients. Mean (+/- SD) hospital stay was 29.7 +/- 15.8 days in the former compared to only 4.8 +/- 3.3 days (p < 0.001) in the latter. Early deaths within 3 months of dialysis initiation were more frequent (7.1 vs 1.6%, p < 0.05) and less patients subsequently were able to be treated out-center (20.1 vs 40.7%, p < 0.05) in group II than in group IA. The overcost induced by late referral may be estimated at 0.25 million French francs per patient. CONCLUSION: An unjustified late nephrological referral of CRF patients still is observed in nearly 20% of cases. Such late referral is detrimental to both patients in terms of altered quality of life and long hospital stay, and to the collectivity due to heavy overcost. Closer cooperation between family physicians and nephrologists is needed to provide optimal management and allow timely preparation to maintenance dialysis of CRF patients. PMID- 9365488 TI - [Renal venous thrombosis: a forgotten complication of acute pyelonephritis]. AB - BACKGROUND: Renal vein thrombosis, long recognized as a classical complication of acute pyelonephritis, has become exceptional since the advent of antibiotics. CASE REPORT: An 85-year-old woman was hospitalized for acute Escherichia coli nephritis. Computed tomography with contrast agent injection was performed due to clinical improvement after an 8-day course of antibiotics and demonstrated purulent urine collection on an obstructive calicial stone as well as homolateral thrombosis of the renal vein. Duplex Doppler confirmed the diagnosis. Pulmonary embolism was evidenced by pulmonary scintigraphy. The clinical course was satisfactory after urine drainage and efficacious antibiotics. CONCLUSION: Renal vein thrombosis remains a severe though uncommon complication of acute pyelonephritis. Computed tomography with iodine, contrast agent or duplex Doppler allows noninvasive diagnosis. PMID- 9365489 TI - [Value of the systematic search of Chlamydia trachomatis by molecular biology in urine during an interview for detecting HIV]. PMID- 9365490 TI - [Misuse of buprenorphine-benzodiazepines combination: 6 deaths]. PMID- 9365491 TI - [Lead poisoning and shooting practice. Experience of the Anti-Poison Center of Marseilles]. PMID- 9365492 TI - [Spontaneous periodic hypothermia. 2 cases]. PMID- 9365493 TI - [Value of early management of patients with chronic renal failure]. AB - The objective of early referral in patients with chronic renal failure is to prevent complications as the disease progresses to the stage where dialysis or transplantation become necessary. Early diagnosis requires a systematic assessment of glomerular function in all patients with signs suggestive of renal disease. Screening programs are also recommended in populations at risk with vascular disease, diabetes, occupational exposure to nephrotoxic substances, or a potentially nephrotoxic treatment. Once stabilized, chronic renal failure usually progresses inevitably to end-stage disease. In France, the estimated annual incidence of chronic renal failure defined as creatininemia > 200 or 300 mumol/l is approximately 200 patients per million inhabitants and that of end-stage disease at 80 per million. Although access to replacement therapy is not limited in France, a certain number of patients are still seen at a late stage of the disease. When dialysis is initiated after the development of severe uremia, patients generally have a poor nutritional status, more severe acidosis and anemia and poorly controlled hypertension; the first dialysis session often occurs in an emergency setting. In this issue of La Presse Medicale, Jungers et al. demonstrate the higher morbidity and increased cost of the first hospitalization in patients without prior follow-up. An optimal treatment aimed at preserving renal function as long as possible can have a beneficial effect on preventing higher morbidity and mortality after beginning substitution therapy. Nephrology referral should be centered on controlling anemia with recombinant human erythropoietin, high blood pressure with appropriate drugs (particularly converting enzyme inhibitors), nutritional status with adapted protein-calorie intake, and renal osteodystrophy with calcium carbonate or recombinant growth hormone in children. Patients must also be prepared for definite dialysis both in terms of medical risk (hepatitis B vaccination) and psychosocial adaptation. PMID- 9365494 TI - [Must we justify our medical decisions?]. AB - To provide an equal or better health care with limited resources, is an inescapable constraint for health care providers. Every physician and clinical decision maker must now account for economical and technical resources that are to be invested in diagnostic and therapeutic procedures, in public as well as in private medical practice. Every medical decision must be endorsed in relation with the expected benefits and risks for the patient and/or the society. Methods and protocols must provide a definite efficiency and rely on a better management of resources allowed to health services and facilities. Words, concepts and basic principles of medical decision analysis are inescapable tools to cope with uncertainty, to evaluate medical decisions according to their expected consequences, objective and subjective, for a definite patient in a bedside situation, as for a larger community. In a context of economic constraint, rational decision analysis is a prerequisite for a better quality of care, optimizing expected results, personal preferences and expenses of financial, technical and human resources in order to save time, risks and suffering. PMID- 9365495 TI - [Parkinson's disease. The parkinsonian patient treated with L. Dopa, the 30th anniversary of a new disease]. PMID- 9365496 TI - [Parkinson disease and parkinsonian syndromes]. PMID- 9365497 TI - [Parkinson disease. Medical treatment]. PMID- 9365498 TI - [Parkinson disease. Role of surgical treatment]. PMID- 9365499 TI - Towards intelligent anticancer drug screening in the post-genome era? PMID- 9365500 TI - The NCI anti-cancer drug screen: a smart screen to identify effectors of novel targets. PMID- 9365501 TI - Uptake of tetraphenylporphycene and its photoeffects on actin and cytokeratin elements of HeLa cells. AB - In the present work we have continued our studies in the photobiological properties of the 2,7,12,17-tetraphenylporphycene (TPPo). In particular, the uptake, the subcellular localization and the photoeffects on two cytoskeletal elements (actin, microfilaments and cytokeratin intermediate filaments) of HeLa cells have been analyzed. The uptake kinetics of TPPo, determined by fluorescence spectroscopy, was initially very rapid, reaching saturation at approximately 6 h of incubation. This porphycene tends to be accumulated mainly in rounded particles distributed throughout the cytoplasm. The morphological comparison of the localization pattern of TPPo and those of acridine orange and rhodamine 123, which are fluorescence markers for lysosomes and mitochondria respectively, allowed us to confirm that this porphycene is mainly accumulated in lysosomal organelles. The results obtained after treatment with TPPo and red light indicated that this compound is very effective in mediating the photodestruction of lysosomes. The photosensitizing effects on the cytoskeletal elements studied depended on both the irradiation time and the elapsed time after treatment. The implications of damage to lysosomes and actin and cytokeratin filaments on the process of cell death is discussed. PMID- 9365502 TI - Synthesis, cytotoxicity, antitumor activity and sequence selective binding of two pyrazole analogs structurally related to the antitumor agents U-71,184 and adozelesin. AB - Two pyrazole analogs structurally related to the antitumor agents adozelesin and U-71,184 respectively were synthesized. By using a polymerase chain reaction approach, both compounds show selective binding to A + T rich sequences exactly as reference compound U-71,184. In in vitro assays, against L1210 cell lines, both derivatives showed cytotoxicity in the pM range, values comparable with the natural target compound (+)-CC-1065. The most active compound showed very high antitumor activity in mice implanted with L1210 cells (ILS% 363). PMID- 9365503 TI - Azelastine hydrochloride (Azeptin) inhibits peplomycin (PLM)-induced pulmonary fibrosis by contradicting the up-regulation of signal transduction. AB - Inhibition of peplomycin (PLM)-induced pulmonary fibrosis by azelastine hydrochloride (Azeptin) was examined using ICR mice, and the effects of both drugs on signal transduction were investigated. Microscopically, Azeptin (a total of 56 mg/kg for 28 days) suppressed pulmonary fibrosis in mice which received an i.p. injection of a total of 60 or 75 mg/kg PLM. In parallel with the microscopic findings, smaller amounts of collagen were synthesized in the lungs of Azeptin injected mice. PLM enhanced the expression of interleukin-1 beta- and transforming growth factor-beta-mRNA in lungs. In contrast, Azeptin suppressed the expression. Compatible with these in vivo results, Azeptin and PLM contradictively regulated protein tyrosine phosphorylation and c-myc mRNA expression in human gingival and mouse pulmonary fibroblasts. In addition, NF kappa B was activated by fibroblast treatment with 5 micrograms/ml PLM for 1 h, but intranuclear NF-kappa B was decreased by cell treatment with 10(-5) M Azeptin. From these results, it is concluded that Azeptin inhibits PLM-induced pulmonary fibrosis by antagonizing the up-regulation of signal transduction. PMID- 9365505 TI - Lucke renal adenocarcinoma, an anuran neoplasm: studies at the interface of pathology, virology, and differentiation competence. AB - The northern leopard frog, Rana pipiens, is vulnerable to a herpesvirus-induced renal tumor. The Lucke renal adenocarcinoma is metastatic as a function of temperature. The cloning procedure of nuclear transplantation has been used to study the differentiation potential of the tumor genome. This paper summarizes current studies of the pathology, virology, and differentiation competence of the Lucke tumor. PMID- 9365504 TI - Synthesis, DNA binding, cytotoxicity and sequence specificity of a series of imidazole-containing analogs of the benzoic acid mustard distamycin derivative tallimustine containing an alkylating group at the C-terminus. AB - In an attempt to produce additional alkylation and crosslinking in the minor groove of DNA, imidazole-containing analogs of distamycin were synthesized with benzoic acid mustard (BAM) and methoxyaziridinyl moieties present at the N- and C termini, respectively. Analogs 1a-c differed in the number of methylene units (2 4 respectively) between the C-terminal carbonyl group and the methoxyaziridinyl moiety. DNA binding affinity to several polynucleotides decreased with increasing linker length, whereas DNA interstrand crosslinking ability, as measured by a plasmid gel based assay, increased. The in vitro cytotoxicity in human chronic myeloid leukemia K562 cells and the panel of human tumor cell lines at the National Cancer Institute decreased with increasing number of methylene units, and no increase in cytotoxicity was observed over compound AR-1-122 which did not contain the methoxyaziridinyl moiety. 1a-c had the same sequence selectivity of alkylation as AR-1-122, showing alkylation only at 5'-TTTTGPu sequences. The relative binding to these sequences decreased with increasing number of methylene units. The addition of a methoxyaziridinyl moiety in this group of imidazole and BAM-containing compounds can, therefore, increase crosslinking ability to naked DNA but this does not result in an increase in cytotoxicity. In contrast the cytotoxicity was related to their ability to produce sequence specific alkylation at 5'-TTTTGPu sequences. PMID- 9365507 TI - Genes, synapses, and long-term memory. PMID- 9365506 TI - Jean Brachet Memorial Lecture to the Ninth International Conference of the International Society of differentiation: genomic potential--Acetabularia to mammals. PMID- 9365508 TI - Cytokine and apoptosis gene networks that control development and cancer. PMID- 9365509 TI - Transcription factors IRF-1 and IRF-2: linking the immune responses and tumor suppression. PMID- 9365510 TI - Differentiation commitment in normal hemopoiesis and leukemic transformation. AB - Differentiation commitment events are essential for the initiation of hemopoiesis and, in one form or another, occur continuously during adult hemopoiesis. The most studied type of differentiation commitment decision a hemopoietic cell can make involves the alternative choice of self-renewal versus the formation of progeny destined for maturation. Aberration in this commitment choice is a key abnormality necessary for the formation of a leukemic population. PMID- 9365512 TI - Human genome project: Italian contribution. Future directions. PMID- 9365511 TI - Intercellular adhesions as determinants of tissue assembly and malignant invasion. PMID- 9365514 TI - Mouse metanephric kidney as a model system for identifying developmentally regulated genes. PMID- 9365513 TI - Characterization and function of Xnf7 during early development of Xenopus. PMID- 9365516 TI - A cascade of transcriptional control leading to axis determination in Drosophila. PMID- 9365515 TI - Induction of epithelial branching tubulogenesis in vitro. PMID- 9365518 TI - Baculovirus interaction with host apoptotic pathways. AB - Baculoviruses possess at least two different classes of anti-apoptotic genes which allow them to block apoptosis of their host cells, thereby increasing the infectivity of the virus and extending the range of cells and hosts that can be efficiently infected. One of these genes, p35, encodes a broadly acting inhibitor of the caspase family of cysteine proteases involved in the induction and execution of apoptotic cell death. The other class of genes, the iaps, are found in higher eukaryotes, as well as baculoviruses, and appear to function at an earlier point in the pathway(s) leading to apoptosis. The IAPs appear to have a more limited role, and the action of at least some of these proteins may be confined to a narrower spectrum of signal transduction pathways. Characterization of the iaps has provided insight into the basis of a prominent human genetic disorder. Both classes of baculovirus inhibitors are proving to be useful in unraveling the molecular pathways governing cellular apoptosis. PMID- 9365517 TI - Effects of HOX homeobox genes in blood cell differentiation. AB - The burgeoning number of articles concerning the role of HOX genes and hematopoiesis ensures that this will continue to be an area of very active research. It seems clear that HOX genes are expressed in stage- and lineage specific patterns during early stages of hematopoietic development and differentiation. Several lines of evidence suggest that multiple genes of the HOXB (B2, B4, B6-B9), HOXC (C6, C8), and HOXA (A5) are involved in erythropoiesis. Similarly, a number of genes of the HOXA, HOXB, and HOXC appear to play a role in lymphoid cells. Furthermore, several genes, such as A9, A10, B3, B7, and B8, may control myelomonocytic differentiation. The question arises as to whether such a multiplicity of HOX genes reflects redundancy or indicates subtlety of the regulatory machinary. A similar complexity has been observed for hematopoietic cytokines, and the current view is that, although multiple molecules may have similar or overlapping effects, each factor has a specific function and regulatory combinations appear to play a critical role in controlling hematopoietic cell processes (99). One challenge for the future is to delineate in more detail the precise expression patterns of these genes in the many distinct subpopulations of blood cells and during fetal development. Overexpression of HOX genes in hematopoietic cells can dramatically perturb the differentiation of various cell lineages and can contribute to leukemogenesis. Future studies may involve the overexpression of alternatively spliced versions of different HOX genes or of truncated versions of HOX genes to ascertain the functional domains of the proteins that mediate the biologic effects. The findings in HOX knockout mice confirm a role for these genes in normal blood cell development. Further work in this area will require careful examination of fetal hematopoiesis and of animals bearing multiple HOX gene knockouts. Involvement of HOX genes in leukemia is just beginning to be appreciated. Establishing the true extent of HOX gene mutations in human disease will require strategies such as comparative genomic hybridization (100) and analysis of high density oligonucleotide arrays (101). The holy grail of homeobox work is to discover the physiologic processes and specific target genes regulated by HOX proteins. Given the broad range of tissues in which HOX genes are expressed, they would appear to be involved in very basic cellular processes, e.g., cell proliferation and death, adhesion, and migration, etc., rather than the direct regulation of tissue specific genes. The search for target genes may be made easier by the further characterization of cooperative DNA binding between HOX proteins and other transcription factors. We speculate that HOX proteins do not behave as conventional transcriptional activators or inhibitors but rather may mark genes for potential future activation, i.e., they may establish competency to execute specific differentiation programs, with the actual activation being accomplished by transcriptional pathways triggered by exogenous signals. This proposed function may be an architectural one, involving changes in the conformation of DNA and/or altering interactions between DNA and histones, thus making areas of the genome more or less accessible to other protein factors (102). If this is the case, we may need to develop new assays to discern the molecular action of HOX proteins. The ease of manipulating the hematopoietic systems would appear to make it a very attractive model for explicating the general functions of this remarkable family of genes. PMID- 9365519 TI - Control of invasive growth by the HGF receptor family. PMID- 9365520 TI - Distinct characteristics of heregulin signals mediated by HER3 or HER4. AB - Members of the epidermal growth-factor-receptor tyrosine-kinase (EGFR) family play important roles both in normal growth regulation/cell differentiation and in the genesis and progression of human neoplasia. In the present study, we analysed distinct heregulin (HRG) signals mediated by the HRG receptors HER3 and HER4. In overexpression cell systems, we demonstrate that HRG-induced transformation by "kinase-impaired" HER3 is dependent on coexpression of kinase active HER2. In cells coexpressing HER2 and HER4, however, both kinases significantly contribute to the HRG-induced mitogenic stimulus. In addition, we show that HER3 is no substrate of HRG-activated HER4. Analysis of EGFR crosstalk in a panel of human carcinoma cell lines revealed mainly HRG-induced activation of HER2/HER3, whereas HER4 activation is also detectable to various extents. Evidence for HRG-induced activation of HER3 and/or HER4 indicates relevance of cell-specific expression patterns of these high- and low-affinity HRG receptors in the modulation of a ligand-induced stimulus. Specific signal modulation and definition can be demonstrated further by distinct time courses of mitogen-activated protein (MAP) kinase (MAPK) activation, which are induced by distinct HRG isotypes via differential binding to HER2/HER3 versus HER2/HER4. In concert, these mechanisms of signal modulation may be decisive for the diverse biological activities of HRG in different cell types. PMID- 9365521 TI - Differential requirement of Grb2 and PI3-kinase in HGF/SF-induced cell motility and tubulogenesis. AB - Hepatocyte growth factor/scatter factor (HGF/SF) is a multifunctional cytokine that induces mitogenesis, motility, invasion, and morphogenesis of several epithelial and endothelial cell lines in culture. The receptor for HGF/SF has been identified as the Met tyrosine kinase. To investigate the signaling pathways that are involved in these events, we have generated chimeric receptors containing the extracellular domain of the colony stimulating factor-1 (CSF-1) receptor fused to the transmembrane and intracellular domains of the Met receptor (MET). Madin-Darby canine kidney (MDCK) epithelial cells, expressing the CSF-MET chimera dissociate, scatter and form branching tubules in response to CSF-1. However, cells expressing a mutant CSF-MET receptor containing a phenylalanine substitution for tyrosine 1356 (Y1356F) are unable to scatter or form branching tubules following stimulation with CSF-1. Tyrosine 1356 is essential for the recruitment of multiple substrates including Grb2, the p85 subunit of PI3-kinase, and PLC gamma. To investigate the role of these signaling pathways, we have generated a mutant receptor that selectively fails to associate with Grb2, and have treated MDCK cells with potent inhibitors of PLC gamma, PI3-kinase, and p70S6K, a downstream target of PI3-kinase. Our results implicate pathways downstream from PI3-kinase in cell dissociation and scatter, whereas pathways downstream from Grb2 are required for branching tubulogenesis in MDCK cells. PMID- 9365522 TI - Cell interactions in the mouse yolk sac: vasculogenesis and hematopoiesis. PMID- 9365524 TI - Vascular endothelial growth factors VEGF-B and VEGF-C. PMID- 9365523 TI - Molecular mechanisms of vasculogenesis and embryonic angiogenesis. PMID- 9365525 TI - Hematopoietic stem cells: embryonic beginnings. PMID- 9365527 TI - Regulatory mechanisms governing FGF-4 gene expression during mouse development. PMID- 9365526 TI - Naturally occurring and therapy-induced antibodies to human granulocyte colony stimulating factor (G-CSF) in human serum. AB - Sera were obtained from two groups of patients. Group A included 7 patients with low-grade non-Hodgkin's lymphoma treated with three or more cycles of standard dose chemotherapy and recombinant human granulocyte-colony stimulating factor (rhG-CSF). The cytokine was administered to half the patients after the first chemotherapy cycle and to the other half after the second according to a randomized design and then to all patients from the third chemotherapy cycle on, until documented hemopoietic reconstitution. Group B included 3 patients with high-grade non-Hodgkin's lymphoma, 1 patient with resistant Hodgkin's disease, and 1 patient with multiple myeloma who received high-dose chemotherapy and rhG CSF. Anti-G-CSF antibodies were detected in the sera of 4 patients. Both immunoglobulin IgM and IgG antibodies were detected at low levels in pretreatment sera from one group A patient. IgG antibody titers increased markedly during the first and second periods of G-CSF administration. IgG class antibodies developed in 3 groups B patients during the first course of rhG-CSF administration. Circulating anti-G-CSF antibodies did not seem to affect hematological recovery. Low levels of anti-G-CSF antibodies were also detected in sera (15/135) from different healthy adults and in sera (5/40) from umbilical cord blood. Saturable antibody binding and competition enzyme-linked immunosorbent assay (ELISA) and immunoblotting confirmed antibody specificity. PMID- 9365528 TI - Role of the Rb/E2F pathway in cell growth control. PMID- 9365529 TI - Structure and function of the human chromosome 15 imprinting center. AB - The Prader-Willi syndrome (PWS) and the Angelman syndrome (AS) are distinct neurogenetic disorders that are caused by a deficiency of paternal (PWS) or maternal (AS) contributions to chromosome 15. The affected genes are located in an imprinted chromosomal domain of 2 Mb, which is controlled by an imprinting center (IC). The IC has been mapped to a 100-kb region including the SNRPN gene and appears to have a bipartite structure. Mutations of the proximal part of the IC block the paternal-->maternal imprint switch during female gametogenesis, whereas mutations of the distal part of the IC block the maternal-->paternal imprint switch during, male gametogenesis. Imprinting involves differential DNA methylation, which appears to be instrumental in the regulation of gene activity and can be used for diagnostic purposes. PMID- 9365530 TI - Developmental consequences of two paternal copies of imprinted chromosome region distal 7 in mice. PMID- 9365531 TI - p53 tumor-suppressor gene: clues to molecular carcinogenesis. AB - The tumor-suppressor gene product p53 is clearly a component in several biochemical pathways, including transcription, DNA repair, genomic stability, cell-cycle control and apoptosis, that are central to human carcinogenesis. The p53 is functionally inactivated by mutational, viral, and cellular mechanisms in the majority of human cancers. Analysis of the spectrum of p53 mutations provides clues to the etiology and molecular pathogenesis of cancer. Recent insight into the p53-mediated biochemical pathways of cell-cycle arrest and apoptosis has provided further understanding of the mechanisms related to p53-mediated tumor suppression. This insight in turn may provide the potential molecular targets for the development of rational multimodality cancer therapy, including chemo-, immuno-, and gene-therapeutic strategies. The convergence of previously parallel lines of basic, clinical, and epidemiologic investigation may provide an opportunity to transfer research findings rapidly from the laboratory to the clinic. PMID- 9365532 TI - Functional evidence for tumor-suppressor activity on chromosome 15 in human skin carcinoma cells and thrombospondin-1 as the potential suppressor. PMID- 9365533 TI - Ovarian carcinogenesis and the biology of ovarian surface epithelium. PMID- 9365534 TI - Telomerase in human development and cancer. AB - A potentially rate-limiting step in cancer progression is the conversion of a normal human cell into one capable of indefinite proliferation. There are at least two different cellular mechanisms that must be overcome before immortalization occurs. The first step generally requires inactivation of the pathways involving two tumor-suppressor genes, p53 and pRB, and the second step almost always involves the reactivation of the ribonucleoprotein enzyme telomerase. Telomerase synthesizes hexameric repeats (TTAGGG) onto telomeric ends, thereby compensating for telomeric losses that in its absence occurs at each cell division. Telomerase is present in human embryonic tissues, is not detected in most adult tissues, but is upregulated or reactivated in almost 90% of all human cancers. In the present article, I review the telomere-telomerase theory of aging and cancer including the roles of telomerase during human development, in differentiation, and in cancer. Research into the regulation of this enzyme may lead to methods to facilitate the accurate diagnosis of cancer and to the development of novel antitelomerase cancer therapeutics. PMID- 9365535 TI - E-cadherin/catenin/cytoskeleton complex: a regulator of cancer invasion. PMID- 9365536 TI - Molecular mechanisms of melanoma metastasis. AB - The molecular changes associated with the transition of melanoma cells from radial growth phase to vertical growth phase (metastatic phenotype) are not very well defined. Expression of the tyrosine-kinase receptor c-KIT progressively decreases during local tumor growth and invasion of human melanomas. To provide direct evidence that c-KIT plays a role in metastasis of human melanoma, we transfected the c-KIT gene into c-KIT-negative, highly metastatic human melanoma cells and subsequently analyzed their tumorigenic and metastatic potential in nude mice. Enforced c-KIT expression significantly inhibited tumor growth and metastasis. Exposure of c-KIT-positive melanoma cells in vitro and in vivo to stem cell factor (SCF), the ligand for c-KIT, triggered apoptosis of these cells but not of normal melanocytes. These results suggest that the loss of c-KIT receptor may allow malignant melanoma cells to escape SCF/c-KIT-mediated apoptosis, thus contributing to tumor growth and eventually metastasis. The expression of c-KIT and other genes associated with malignant melanoma (such as MCAM/MUC18) is highly regulated by the transcription factor AP-2. The AP-2 protein is not expressed in malignant melanoma cells. Therefore, loss of AP-2 expression might be a crucial event in the progression of human melanoma. PMID- 9365538 TI - Differentiation therapy in acute promyelocytic leukemia: European experience. AB - Acute promyelocytic leukemia (APL) is a subset of acute myeloid leukemia characterized by the morphology of the blast cells (M3 type in the FAB nomenclature), and a specific t(15; 17) translocation. APL was further characterized by a specific sensitivity to all-trans retinoic acid's differentiation effect and the production of a fusion gene altering the gene of RAR alpha and a gene called PML. In vivo differentiation therapy with retinoids in APL patients reduces the risk of relapse and increases the chance of long-term survival. PMID- 9365537 TI - Induction of apoptosis in human non-small cell lung carcinoma cells by the novel synthetic retinoid CD437. AB - Retinoids are promising agents for the prevention and treatment of several human malignancies including lung cancer. However, many lung cancer cell lines are resistant to the growth inhibitory effects of all-trans-retinoic acid (ATRA). Recently, we found that a new synthetic retinoid, 6-[3-(1-adamantyl)-4 hydroxyphenyl]-2-naphthalene carboxylic acid (CD437), which binds selectively to nuclear RA receptor gamma, was the most effective inhibitor of the growth of human non-small cell lung carcinoma (NSCLC) cells among 37 retinoids tested. After a 4-day treatment with CD437 the growth of 8 NSCLC cell lines was inhibited with an IC50 ranging from 0.13 to 0.53 microM. In contrast, ATRA failed to inhibit the growth of any of these cell lines by more than 43% after a 7-day treatment even at 10 microM. The presence of detached rounded cells in treated cultures indicated that CD437 may induce apoptosis. Indeed, this was confirmed by the presence of 20-57% cells with a sub-G1 DNA content and by an enzyme-linked immunosorbent assay (ELISA) of apoptosis. Two retinoids, CD2366 and CD2665, which are antagonists of nuclear retinoid receptor activation, failed to inhibit the effect of CD437 on the growth of the NSCLC cell lines. CD437 failed to suppress the transcriptional activation of the activator protein-1 (AP-1) reporter. These results demonstrate that CD437 can induce apoptosis in NSCLC cells that are resistant to ATRA and that this effect is mediated by a mechanism that may be independent of transactivation of retinoid receptors or transrepression of AP-1. PMID- 9365539 TI - Gene rearrangements in the molecular pathogenesis of acute promyelocytic leukemia. AB - Acute Promyelocytic Leukemia (APL) is a distinct subtype of myeloid leukemia that in the USA alone affects more than 3,000 individuals every year. APL is characterized by three distinct and unique features: i) the accumulation in the bone marrow of tumor cells with promyelocytic features; ii) the invariable association with specific translocations which always involve chromosome 17 and the Retinoic Acid Receptor alpha (RAR alpha) locus; iii) the exquisite sensitivity of APL blasts to the differentiating action of Retinoic Acid (RA). These features have led APL to become the paradigm for therapeutic approaches utilizing differentiating agents. The last 5 years have provided crucial insights into the molecular basis of APL. RAR alpha translocates in 99% of cases to a gene located on chromosome 15 that we initially named myl and subsequently has been called PML. In a few cases, RAR alpha variably translocates to chromosome 11 where it fuses to the PLZF gene or to a newly described partner, NuMA. In addition, RAR alpha is also found translocated to chromosome 5 where it fuses to the NPM gene. The cloning of variant translocations in APL and the comparative analysis of their associated products is crucial for the understanding of the molecular etiopathogenesis of the disease. The generation of animal models, i.e., transgenic mice expressing the fusion genes, will be instrumental in determining the precise contribution of these fusion genes to leukemogenesis. In fact, mice harboring a PML/RAR alpha transgene whose expression is specifically targeted to the myeloid-promyelocytic lineage develop acute myeloid leukemia with promyelocytic features. Moreover, the functional analysis of the various fusion proteins, as well as RAR alpha partners, is revealing striking common features beneath a misleading structural heterogeneity which unravels a possible unifying molecular mechanism towards APL leukemogenesis. PMID- 9365540 TI - Retinoic acid downregulates growth, fibronectin and RAR alpha in 3T3 cells: Ha ras blocks this response and RA metabolism. AB - Retinoic acid (RA) reduced growth, fibronectin, and retinoic acid receptor (RAR alpha) in NIH 3T3 cells but not in cells transformed by the Ha-ras oncogene. RA lowered RAR alpha transcript and protein, increased RAR beta transcripts, and had no effect on RAR gamma. H-ras transformation downregulated RAR expression and abolished responsiveness to RA. Ha-ras-transformed cells were as active as normal NIH-3T3 cells in RA uptake but were unable to degrade it to medium oxidation product, so that, paradoxically, the resistant cells accumulated 20-30-fold as much RA as the sensitive cells. RA sensitivity/insensitivity correlated with RA metabolism/lack thereof in 15 cell lines in serum-free medium. These data suggest a relationship between RA inhibition of cell growth and intracellular RA metabolism. PMID- 9365541 TI - Transforming growth factor beta 1 transduced mouse prostate reconstitutions: I. Induction of neuronal phenotypes. AB - BACKGROUND: We previously showed that retroviral transduction of transforming growth factor beta 1 (TGF-beta 1) induces focally hyperplastic lesions resembling benign prostatic hyperplasia (BPH) and an increase in the number of ganglion-like cells in the mouse prostate reconstitution (MPR) model in vivo. In the present study we further characterize the neuronal phenotypes induced by TGF-beta 1 retroviral transduction in MPRs. METHODS: Computer-assisted morphometric analysis was used to evaluate neuronal density. Neuronal cell markers, including neurofilament, neuron-specific enolase, tyrosine hydroxylase, choline acetyltransferase, L-met enkaphaline, and serotonin, were detected by immunostaining. RESULTS: A fourfold increase in neuronal density was observed in TGF-beta 1 retrovirus-transduced MPRs. The relative frequencies of neuronal subtypes remained similar, with catecholaminergic and cholinergic neurons presenting as the most abundant. We found no evidence of infection of neurons; therefore, increased neuronal density was likely due to paracrine activities. CONCLUSIONS: Our results suggest that enforced TGF-beta 1 expression leads to growth and/or survival of both catecholaminergic and cholinergic neuronal cells in mouse prostate reconstitutions. PMID- 9365542 TI - Transforming growth factor beta 1 transduced mouse prostate reconstitutions: II. Induction of apoptosis by doxazosin. AB - BACKGROUND: To study the possible relationship between adrenergic activities and the pathogenesis of benign prostatic hyperplasia (BPH), we tested the effect of doxazosin, an alpha 1-adrenoceptor antagonist, on prostatic growth in vivo using a mouse model for BPH. METHODS: The mouse prostate reconstitution (MPR) model system with retroviral (BabeTGF-beta 1Neo) transduction of transforming growth factor beta 1 (TGF-beta 1) was used to induce focally hyperplastic BPH-like lesions and increase the number of catecholaminergic neurons. The mice were treated with daily intraperitoneal injections of doxazosin (3 mg/kg). RESULTS: Doxazosin caused a significant reduction in the wet weight of BabeTGF-beta 1 infected MPRs. The percent of PCNA-positive epithelial cells was similar in the doxazosin-treated and water only, control groups. There was a significant increase in the number of epithelial cells undergoing programmed cell death, apoptosis, in the doxazosin group (apoptotic index = 4.7 for doxazosin group vs. 3.1 for control group, P < 0.05). The doxazosin-induced apoptosis was more apparent in TGF-beta 1 transduced MPRs than BAG alpha control MPRs, and was not seen in the prostates of the adult male mice into which the MPRs were engrafted. CONCLUSIONS: Our data demonstrate a novel and potentially important biological activity of doxazosin in vivo in this mouse model of BPH. PMID- 9365543 TI - The mouse prostate reconstitution model of prostate diseases. PMID- 9365545 TI - Morphometric analysis of pediatric and nonhyperplastic prostate glands: evidence that BPH is not a unique stromal process. AB - BACKGROUND: Although quantitative morphometry of benign prostatic hyperplasia (BPH) has been described, there is a paucity of information on the morphometry of the nonhyperplastic prostate. This study determines the histologic composition of prostates obtained from males, ages 2 days to 40 years, in order to provide insights into the morphometry of the "normal" gland. METHODS: The histologic composition of 45 prostates was obtained from autopsies of males with age groups stratified to reflect the neonatal, childhood, peripubertal, adolescent, and young adult periods. Double immunoenzymatic staining and computer image analysis were used to determine the mean area densities of the smooth muscle (SM), connective tissue (CT), glandular epithelium (E), and lumen (L). RESULTS: A progressive decrease in SM area density throughout childhood, prepuberty, and puberty was seen. The density of SM significantly increased following puberty and throughout adolescence and early adulthood. There was a concomitant increase in CT from the neonatal period throughout childhood, prepuberty, and puberty, and a decrease after puberty and throughout adolescence and early adulthood. Since the changes in SM and CT were inversely related, the percent contribution of the stromal compartment to the total gland remained constant. CONCLUSIONS: The stromal to epithelial ratio remains constant from birth to age 40 in nonhyperplastic glands and is similar to the ratios in asymptomatic and symptomatic BPH tissues. PMID- 9365544 TI - Evaluation of the tetracycline-repressible transactivator system for inducible gene expression in human prostate cancer cell lines. AB - BACKGROUND: Studies of genes that may inhibit growth or induce death of cells are facilitated greatly by tightly controlled expression of those genes. A promising system for control of transgene expression over a wide range is the tetracycline repressible transactivator (tTA) system developed by Gossen and Bujard [Proc Natl Acad Sci USA 1992;89:5547-5551]. We investigated the effectiveness of this system in three well-established human prostate cancer cell lines. METHODS: LNCaP, PC-3, and Tsu-Pr1 cells were transfected with a vector coding for the tTA protein and/or a luciferase reporter vector, and luciferase activity was measured in the presence and absence of tetracycline or the tTA protein. RESULTS: In the absence of tetracycline, the tTA system yielded high levels of luciferase activity in all three cell lines. Background luciferase activity in the presence of tetracycline was nearly undetectable in LNCaP cells, moderate in Tsu-Pr1 cells, and more than 20-fold higher in PC-3 than in Tsu-Pr1 cells. Similar background activity was observed in Tsu-Pr1 and PC-3 cells, even in the absence of the transactivator protein. CONCLUSIONS: The tTA system should be useful for stable transfection of cytotoxic transgenes in LNCaP cells and for control of transgene expression over a wide range in Tsu-Pr1 and PC-3 cells. PMID- 9365546 TI - Functional property, norepinephrine content and morphometric findings in human hyperplastic prostate. AB - BACKGROUND: Although alpha-adrenergic blockers are widely used as a treatment of benign prostatic hyperplasia (BPH), it is not clear whether contractile property of hyperplastic prostate to alpha-adrenergic agonist depends upon an area of density of smooth muscle within the respective BPH tissue. METHODS: Functional study and quantitative morphometric analysis were performed on human prostatic specimens obtained by transurethral resection from 22 men with symptomatic BPH. Tissue norepinephrine content was also evaluated. RESULTS: There was a linear correlation between the area of density of smooth muscle and maximum response to phenylephrine (r = 0.457, P = 0.0362). Although the area of density of smooth muscle showed a positive correlation with norepinephrine content (r = 0.437, P = 0.0471), norepinephrine content was not correlated with maximum phenylephrine response. CONCLUSIONS: Contractile response to alpha-adrenergic agonist was directly influenced by the area of density of the smooth muscle within an individual prostate. PMID- 9365547 TI - Prostate volume and cancer in screening programs. AB - BACKGROUND: Prostate cancer screening is studied in a randomized trial in Antwerp, Belgium. The case group receives three screening tests (DRE, TRUS, and PSA). Intermediate evaluation shows that only 1/3 of the biopsy results is positive (35/125). The proposed analysis identifies variables that determine the biopsy outcome. METHODS: Multiple logistic regression analysis is used to regress biopsy results (n = 125) by age (60-74), PSA, PSA-D, prostate volume, TRUS, and DRE. Continuous variables are transformed into quartile values. Robustness of the outcome is tested with ROC and sensitivity analysis on age. RESULTS: Biopsy outcomes are best explained (82.3%) by PSA, DRE, and DRE related to volume. Volume is more sensitive than age to explain the biopsy result. PSA-D, instead of PSA, does not procure more precise information when a high PSA cut-off level is used. Restricting the analysis to the 60-70-year-old age group shows that volume is more sensitive. ROC-analysis confirms the findings. CONCLUSIONS: When performing prostate cancer multitest screening among a wide age range, the use of uniform screening criteria is difficult to accept due to differences in prostate volume. Logistic regression analysis is an appropriate method to identify cut-off levels for prostate volume. PMID- 9365548 TI - Cigarette smoking and prostate cancer: no relation with six measures of lifetime smoking habits in a large case-control study among U.S. whites. AB - BACKGROUND: The study was undertaken to describe the association between lifetime cigarette smoking habits and prostate cancer. Whereas most case-control and cohort studies report no association, the positive findings from some large cohort studies are difficult to ignore. The available information on lifetime smoking habits from most studies is limited however. METHODS: In a study of 1,097 prostate cancer cases and 3,250 matched controls, admitted between 1969 and 1991 to U.S. hospitals, several ordinal measures of lifetime smoking were compared to look for dose-response or threshold associations. RESULTS: No association was seen between prostate cancer and former or current smoking, age started smoking, number of years smoked, cigarettes per day smoked, the number of years since quitting, and lifetime tar exposure. CONCLUSIONS: Our data provide the most complete dose-response smoking information to date, and support the findings from the majority of studies that prostate cancer is not associated with cigarette smoking. PMID- 9365550 TI - Serum markers for monitoring of prostatic carcinoma. AB - BACKGROUND: Serum TPS (tissue polypeptide-specific antigen) has been observed to be characteristic of carcinoma proliferation, and increased levels of TPS seem to be closely related to tumor progression. In this study we wanted to evaluate the importance of the tumor-marker TPS in the diagnosis and follow-up of patients with prostatic carcinoma, and to compare it with prostate-specific antigen (PSA). METHODS: We considered 39 patients with clinically confined disease, who underwent neoadjuvant hormonal therapy and thereafter radical prostatectomy, and 45 patients who did not undergo surgery and underwent hormonal adjuvant therapy alone. PSA and TPS were measured at the time of diagnosis and at regular intervals in the follow-up; TPS was measured in a control group of patients as well. RESULTS: We were able to observe that, in untreated patients, PSA correlates with clinical stage, increasing with increasing tumor stage; a similar correlation was not observed when considering TPS. After androgen ablation we observed a decrease in PSA, but the serum values of TPS remained higher, suggesting that activity still exists inside the tumor. The evaluation of TPS appeared to be of particular interest in the follow-up after radical prostatectomy, especially in patients undergoing hormonal therapy; in fact, we were able to observe that relapse of the disease can be suspected early by the increase of TPS in hormonally treated patients. CONCLUSIONS: We assert that TPS can add useful information on the state of neoplastic illness, especially in patients following adjuvant androgen-suppressive hormonal therapy, after radical prostatectomy; serial measurements of this marker could be useful in the early diagnosis of a relapse. PMID- 9365549 TI - Mechanism and role of growth arrest in programmed (apoptotic) death of prostatic cancer cells induced by thapsigargin. AB - BACKGROUND: More than 95% of metastatic androgen independent prostatic cancer cells per day are in a proliferatively quiescent G0 state [Berges et al.: Clin Cancer Res 1:473-480, 1995] limiting their responsiveness to anti-proliferative chemotherapeutic agents. Novel therapeutics capable of activating the programmed (apoptotic) death pathway in these cells without requiring entrance into the proliferative cell cycle are urgently needed. Thapsigargin (TG) treatment of rapidly growing androgen independent prostatic cancer cells arrests such cells in G0 and induces their programmed death. This raises not only the issue of the mechanism for such growth arrest, but also whether this programmed death is simply a response of rapidly growing cells to growth arrest making cytotoxicity still dependent upon the initial rate of cell proliferation. METHODS: To resolve the mechanism of TG induced growth arrest, rat AT3.1 prostatic cancer cells were analyzed for RNA and protein expression of the growth arrest gene, gadd153, intracellular free Ca2+ levels (Cai), and cell cycle distribution on exposure to TG alone and in combination with Ca2+ chelation induced by BAPTA-AM or BAPTA AM/EGTA. To resolve whether growth arrest is required for TG cytotoxicity, primary cultures of proliferatively quiescent, human prostatic cancer cells were exposed to TG. RESULTS: Co-treatment of androgen independent AT-3 rat prostatic cancer cells with the Cai chelator BAPTA plus TG prevented growth arrest, as monitored by DNA flow cytometry, and failure to induce mRNA and protein for gadd153, demonstrating that growth arrest is due to Cai elevation, not depletion of intracellular Ca2+ pools. In addition, proliferatively quiescent G0 primary cultures of human prostatic cancer cells were resistant to anti-proliferative agents, but could be induced to undergo programmed death by TG as documented by morphological criteria and 14C-labeled DNA fragmentation assays. CONCLUSIONS: These results demonstrate that TG with its ability to elevate Cai induces proliferating prostate cancer cells to growth arrest. Such Cai dependent growth arrest is not required, however, since TG can induce the programmed death of proliferatively quiescent G0 prostatic cancer cells without requiring either growth arrest or progression through the proliferative cell cycle. PMID- 9365552 TI - Marginal donors: a viable solution for organ shortage. PMID- 9365551 TI - Chemoprevention of prostate cancer: the Prostate Cancer Prevention Trial. AB - BACKGROUND: A variety of innovative approaches to the prevention of prostate cancer are now available, including selenium, alpha tocopherol, dietary interventions, and vitamin D. Perhaps the most promising opportunity is based upon considerable evidence that cumulative androgen exposure of the prostate contributes to the age-related risk of prostate cancer. METHODS: The Prostate Cancer Prevention Trial has completed randomization of over 18,000 healthy men to either finasteride or placebo. CONCLUSIONS: While the primary objective of this study is to determine whether finasteride can reduce the period prevalence of prostate cancer over a 7-year period, the biologic and data resources of this study will provide multiple opportunities to better understand this most common cancer in U.S. men. PMID- 9365553 TI - Advantages of intraperitoneal placement of renal transplants. PMID- 9365554 TI - Survival rates of parental donor renal allografts are similar to living unrelated donor grafts: is it due to inadequate nephron supply? PMID- 9365555 TI - Living donor nephrectomy: a 28-year experience at Heidelberg University. PMID- 9365557 TI - Effect of first-day graft nonfunction on the short- and long-term graft survival rates in living related and living unrelated donor renal transplants. PMID- 9365556 TI - Living unrelated kidney transplantation. PMID- 9365558 TI - Pregnancy in renal transplant recipients: an Iranian experience with a report of triplet pregnancy. PMID- 9365559 TI - Comparison of glomerular filtration rate and serum creatinine in renal transplant patients. PMID- 9365560 TI - Post-renal transplant monitoring: the value of biological assays. PMID- 9365561 TI - Ideal body weight predicts remaining renal function following donor nephrectomy. PMID- 9365562 TI - Relationship between macrophage infiltration of renal allografts and chronic renal impairment. PMID- 9365563 TI - Clinical course and outcome of pregnancies in recipients of renal allografts. PMID- 9365564 TI - Perioperative monitoring of the cortical microcirculation in clinical renal transplantation by thermodiffusion. PMID- 9365565 TI - Renal transplant fibrosis: histomorphometric assessment of early renal transplant biopsies for markers of chronic rejection. PMID- 9365566 TI - Outcome of children and adolescents with recurrent nephrotic syndrome and focal segmental glomerulosclerosis after renal transplantation. PMID- 9365567 TI - Kidney transplantation and pregnancy. PMID- 9365568 TI - Causes and effects of delayed graft function in cadaveric renal transplantation: a multivariate analysis. PMID- 9365569 TI - Life-span of living-related kidney donors. PMID- 9365570 TI - Transplantation of small pediatric kidneys in adult recipients: a 22-year experience. PMID- 9365571 TI - ATG versus OKT3 in the treatment of steroid-resistant rejection following living related donor renal transplantation. PMID- 9365572 TI - Comparative study of ultrasonogram, renogram, and fine needle aspiration cytology in the diagnosis of acute allograft rejection. PMID- 9365573 TI - Quality of life and long-term follow-up after kidney transplantation: a 30-year clinical study. PMID- 9365574 TI - Tolerance and chimerism in liver transplantation. PMID- 9365575 TI - Cyclosporine A reduction and withdrawal in liver transplantation: a risk-benefit analysis. PMID- 9365577 TI - Is donor age a risk factor for poor graft function after orthotopic liver transplantation? PMID- 9365576 TI - Adhesion molecules during adverse events after human liver transplantation. PMID- 9365578 TI - Determination of alpha- and Pi-glutathione-S-transferase will improve monitoring after liver transplantation. PMID- 9365579 TI - Expanded liver donor age over 60 years for hepatic transplantation. PMID- 9365580 TI - Liver transplantation in patients with polycystic liver disease. PMID- 9365581 TI - Transplantation for unresectable liver tumors in children. PMID- 9365583 TI - Recurrent hepatitis C infection following orthotopic liver transplantation is predicted by posttransplant serum and hepatic allograft viral titers. PMID- 9365582 TI - Analysis of donor criteria and its implications on the outcome of clinical liver transplants. PMID- 9365584 TI - Liver transplantation in HBsAg+ patients with postoperative immunoprophylaxis. PMID- 9365586 TI - Significance of isolated pretransplant hepatitis B anticore antibody. PMID- 9365585 TI - Association between hepatitis and rejection: upregulation of cytokines and extracellular matrix parameters. PMID- 9365587 TI - Role of liver transplantation in the management of liver trauma. PMID- 9365589 TI - Hemodynamics in human liver transplantation with inferior vena cava preservation. PMID- 9365588 TI - Biliary complications after T-tube placement in liver transplant patients. PMID- 9365590 TI - Vascular complications, treatment, and outcome following orthotopic liver transplantation. PMID- 9365591 TI - Management of allograft-replaced right hepatic arteries in liver transplantation: a review of the University of Miami experience and a preferred method of reconstruction. PMID- 9365592 TI - Positive donor cytomegalovirus IgG status as a major risk factor for liver allograft recipient infection. PMID- 9365594 TI - No impairment of hepatic venous outflow after "piggy-back" liver transplantation. PMID- 9365593 TI - Liver transplantation: incidence and management of deep venous thrombosis and pulmonary emboli. PMID- 9365595 TI - Management of portal vein thrombosis in liver transplantation. PMID- 9365596 TI - A 4-year small-center experience in liver transplantation. PMID- 9365598 TI - FK 506 and mycofenolate mofetil rescue for acute steroid-resistant and chronic rejection after liver transplantation. PMID- 9365597 TI - Liver transplantation: experience at King Fahad National Guard Hospital, Riyadh, Saudi Arabia. PMID- 9365600 TI - Flow cytometric DNA analysis of paraffin-embedded hepatocellular carcinoma from patients treated by orthotopic liver transplantation. PMID- 9365599 TI - Hepatitis C recurrence in liver transplant recipients. PMID- 9365601 TI - Indications for mycofenolate mofetil therapy after liver transplantation. PMID- 9365602 TI - Immediate postoperative course and complications of orthotopic liver transplantation: the first 31 adult patients. PMID- 9365603 TI - Heart and lung transplantation: La Pitie experience. PMID- 9365604 TI - Combination treatment effectively intercepts advanced acute cardiac rejection. PMID- 9365605 TI - Bilateral lung transplantation for pulmonary hypertension. PMID- 9365606 TI - Immune monitoring in cardiac transplant recipients. PMID- 9365607 TI - Downsizing of the donor lung: peripheral segmental resections and lobar transplantation. PMID- 9365608 TI - FK 506 in simultaneous pancreas/kidney transplantation: the University of Miami experience. PMID- 9365609 TI - Destruction of rat exocrine pancreatic tissue by photodynamic therapy. PMID- 9365610 TI - Experimental islet cell transplantation in rats. PMID- 9365612 TI - Our experience with pancreatic graft extraperitoneal placement. PMID- 9365611 TI - Urodynamic findings following bladder-drained simultaneous pancreas-kidney transplantation. PMID- 9365613 TI - HLA analysis of kidney transplants performed in member countries of MESOT. Middle East Society for Organ Transplantation. PMID- 9365614 TI - HLA-A, -B, -DR antigens in the Greek Cypriot population. PMID- 9365615 TI - A comparative study of HLA Allele frequency in Lebanese, Arabs, United Arab Emirates, and east Indian populations. PMID- 9365616 TI - Neoral versus Sandimmun in kidney-pancreas transplantation. PMID- 9365617 TI - Long-term experience with mycofenolate mofetil in the prevention of renal allograft rejection. PMID- 9365618 TI - Study of circadian variation of cyclosporine pharmacokinetics. PMID- 9365619 TI - Mycophenolate mofetil (Cellcept) in renal transplantation: the European experience. The European Mycophenolate Mofetil Co-operative Study Group. PMID- 9365620 TI - Mycophenolic acid and mycophenolic acid glucuronide trough levels after renal transplantation. PMID- 9365621 TI - Cyclosporine Neoral in renal transplant recipients: impact on hepatic dysfunction. PMID- 9365623 TI - Long-term experience with Sandimmun Neoral: results in de novo and stable renal transplant patients after 24-month treatment. The German Neoral Study Group. PMID- 9365622 TI - Experience with new cyclosporine formulations: Consupren and Neoral in renal transplant patients. PMID- 9365624 TI - Influence on the long-term outcome of renal allografts by fosfomycin. PMID- 9365625 TI - Immunosuppressive therapy in renal transplant patients according to patient immunological status. PMID- 9365626 TI - Correlation between cyclosporine pharmacokinetics and immunologic parameters in dialyzed patients awaiting transplantation. PMID- 9365627 TI - Long-term results after primary successful FK 506 treatment of steroid- and OKT3 resistant rejection in renal transplant recipients. PMID- 9365628 TI - CD2+, CD3+, and CD19+ depletion after a course of antithymocyte globulin for a steroid-resistant rejection. PMID- 9365629 TI - Donor-specific transfusion under the new cyclosporine A formulation Consupren versus azathioprine, Imuran. PMID- 9365630 TI - Transfusion-induced immunosuppression: abrogation by leucodepletion. PMID- 9365631 TI - Effect of peritransplant FTY720 alone or in combination with posttransplant FK 506 in a rat model of cardiac allotransplantation. PMID- 9365632 TI - A comparative analysis of methyl prednisone pulse versus orthoclone therapy in the management of acute cellular rejection. PMID- 9365633 TI - Mycophenolate mofetil rescue therapy in liver transplant recipients: an extended follow-up. PMID- 9365634 TI - Histocompatibility in live related donor renal transplantation. PMID- 9365635 TI - Flow cytometric analysis of antidonor-specific antibodies in liver transplant. PMID- 9365636 TI - Allograft instability with frequent acute rejections and early chronic transplant glomerulopathy related to suboptimal doses of cyclosporine A. PMID- 9365637 TI - Mass conversion from Sandimmun to Sandimmun Neoral: 1 1/2-year experience. PMID- 9365638 TI - Use of donor-specific bone marrow to facilitate tolerance in clinical solid organ transplantation: old facts and future prospects. PMID- 9365639 TI - Update on the results of non-heart-beating donor kidney transplants. PMID- 9365640 TI - Effect of L-arginine and oligotide on liver ischemia-reperfusion injury. PMID- 9365641 TI - Improved preservation of the small bowel by luminal gas oxygenation: energetic status during ischemia and functional integrity upon reperfusion. PMID- 9365642 TI - Neutrophil elastase activity in hepatic ischemia reperfusion injury. PMID- 9365644 TI - A new model of renal warm ischaemia reperfusion injury. PMID- 9365643 TI - Effect of reperfusion on human allograft ICAM-1 expression and its correlation with histological evidence of reperfusion changes. PMID- 9365645 TI - Long-term effect of cyclooxygenase inhibition with acetylsalicylic acid in cadaveric renal transplants. PMID- 9365646 TI - Some problems related to discordant xenografting. PMID- 9365647 TI - Role of leukocyte adhesion molecules during ex vivo kidney xenoperfusion. PMID- 9365648 TI - Correction of acute liver cell failure disorders through liver xenoperfusion: experimental study. PMID- 9365649 TI - Changes in serum proteins during isolated pig liver xenoperfusion. PMID- 9365650 TI - Plasma amino acid study during discordant liver xenoperfusion. PMID- 9365651 TI - Successful xeno long-term cryopreserved fetal liver fragment transplantation from pig to rat or beagle omentum using immunocapsule. PMID- 9365652 TI - Studies of xeno tissue typing: xeno MLR and Southern blotting using HLA, C4A, Bf, and SLA cDNA probes and TCRV-beta clonotyping. PMID- 9365653 TI - Can fetal xeno whole-organ (heart, lung, kidney, and liver) grafts escape from hyperacute rejection in experimental discordant combinations as compared with adult xenografts? PMID- 9365654 TI - The effect of MX-1 and FOY on survival of discordant cardiac xenograft. PMID- 9365656 TI - Diagnosis and classification of the severity of graft versus host disease after experimental small-bowel transplantation in small animal models. PMID- 9365655 TI - A second native renal allograft of donor origin in a model of chronic rejection demonstrates improved long-term function. PMID- 9365657 TI - Early acute rejection episodes are reversible following retransplantation into a syngeneic donor and do not progress to chronic rejection. PMID- 9365658 TI - alpha-Glutathione-S-transferase is a sensitive marker of hepatocellular damage due to warm or cold ischemia in pig liver transplantation. PMID- 9365659 TI - Renal effects of long-term administration of growth hormone in prepubertal uninephrectomized rats. PMID- 9365660 TI - Organ donation: Transplant Games, the "Island Effect," and other successful methods. AB - We have alluded to data showing that effective organisation has a well-documented effect on organ donation. We have also presented data demonstrating the positive effect of the Transplant Games on public opinion and through positive media influence, producing a very marked increase in organ donation. Attention has also been drawn to the surprising phenomenon we call the "Island Effect," which may endorse the concept of decentralisation and close communication as an effective way of increasing organ donation. Finally, we conclude that, with professional help, both into the organisation of organ donation, and the creation of a positive media effect on public opinion, there is a great scope for increasing human organ donation to levels that are very much higher than that which we now experience. Both the Transplant Games and the "Island Effect" have indicated routes that we can and must explore and use to narrow the vital gap between organ need and organ supply for transplantation. PMID- 9365661 TI - Fluvastatin in renal transplantation. PMID- 9365662 TI - Problems of diagnosis and treatment of tuberculosis following renal transplantation. PMID- 9365664 TI - Clinical and physiological responses to total parathyroidectomy after renal transplantation. PMID- 9365663 TI - Use of rHu GM-CSF in renal-transplant patients developing leukopenia. PMID- 9365665 TI - How to evaluate CMV disease in renal transplantation. PMID- 9365666 TI - Use of intravenous immunoglobulin in organ transplantation for noninfectious indications. PMID- 9365667 TI - Cyprus Bone Marrow Donor Registry. PMID- 9365668 TI - Donor retrieval patterns in a Saudi multiorgan transplant center. PMID- 9365669 TI - Study of malignancy among Egyptian kidney transplant recipients. PMID- 9365671 TI - Surgical management of vesicoureteral reflux following renal transplantation. PMID- 9365670 TI - Results of 144 consecutive renal transplants from living-related donors. PMID- 9365672 TI - Ureteral complications after renal transplantation: review of preventive measures. PMID- 9365673 TI - Pediatric renal transplants in Cyprus. PMID- 9365674 TI - Our experience with pancreatic graft extraperitoneal placement. PMID- 9365675 TI - Utilization of liver allografts from donors older than 60 in Israel: benefits and risks. PMID- 9365677 TI - Relevance of small hospitals for increasing donation rates. PMID- 9365676 TI - Scandiatransplant: organ transplantation in the Nordic countries 1996. AB - The Nordic collaboration in organ transplantation was initiated nearly 30 years ago in the frame of Scandiatransplant. With a recent formalization of its structure, Scandiatransplant has become a modern organ exchange organization. The increasing activities of Scandiatransplant clearly reflect the continuously growing need for a close and firm Nordic collaboration in the transplantation field, for the benefit of the numerous patients waiting for an organ transplant. PMID- 9365678 TI - Information on new transplant legislation: how it was received by the general public and the action that ensued. AB - The information campaign was successful. The leaflet was observed by many and discussed by two-thirds of those who had seen it, most often with relatives. All who have registered with the donor register have taken a stand on the donation of organs and tissues for transplantation or other medical purposes. Many more have probably signed donor cards or told the next of kin. It is suggested that the population has been properly informed. The number of cadaver donors, which has decreased the last number of years, seems to be unaffected. PMID- 9365679 TI - In situ split liver procedures in cadaver and living-related donors. PMID- 9365680 TI - Experience from a single institution: 3000 consecutive kidney transplants during 30 years. PMID- 9365681 TI - Myeloperoxidase in urine: a new marker for distinction between rejection and urinary tract infection after renal transplantation. PMID- 9365682 TI - Influence of matching for HLA-DR in first cadaveric renal transplantation in nonsensitized recipients. PMID- 9365683 TI - Results of donor kidney pairs after local versus HLA-dependent allocation. PMID- 9365684 TI - Early bacterial and fungal infections in liver transplantation after oral selective bowel decontamination. PMID- 9365685 TI - Pretreatment with L-arginine reduces ischemia/reperfusion injury of the liver. PMID- 9365686 TI - Complement membrane attacks complex deposition and decrease in protectin (CD59) expression in liver allografts during acute rejection. PMID- 9365687 TI - Expression of adhesion molecules in liver allografts during acute and chronic rejection. PMID- 9365688 TI - Progressive renal impairment in liver transplant recipients on a cyclosporine based protocol: 5 year follow-up with glomerular filtration rate measurements. PMID- 9365689 TI - A 10-year prospective study of IDDM patients subjected to combined pancreas and kidney transplantation or kidney transplantation alone. PMID- 9365690 TI - Transplant therapy for end-stage diabetic nephropathy in a single centre. PMID- 9365691 TI - Glucose tolerance following segmental and whole-organ pancreas transplantation. PMID- 9365693 TI - Early experience with a long-distance collaborative human islet transplant programme. PMID- 9365692 TI - Prediction of glucose tolerance with glucagon stimulation in pancreas transplanted patients. PMID- 9365694 TI - Noninvasive rejection monitoring after heart transplant. PMID- 9365695 TI - Heart allograft rejection in rats triggered by H2 inhibitors. PMID- 9365696 TI - Transplantation immunology: a brief update. PMID- 9365697 TI - A randomized clinical trial using ATG Fresenius or ATG Merieux as induction therapy in kidney transplantation. PMID- 9365698 TI - Pharmacokinetic cyclosporine A profiles under long-term Neoral treatment in renal transplant recipients: does fat intake still matter? PMID- 9365699 TI - Influence of different CyA formulations and calcium channel blocker phenyhidine regimens on intracellular (erythrocyte) calcium levels after kidney transplantation. PMID- 9365700 TI - Cyclosporine influences liver function as measured by IODIDA clearance rate: a study in liver and kidney transplant patients, and healthy volunteers. PMID- 9365701 TI - Transplantation with unrelated bone marrow in leukemic patients above 40 years of age. PMID- 9365703 TI - Different expression of adhesion molecules ICAM-1 and VCAM-1 and activation markers MHC class II and IL-2R in acute and chronic rejection of rat kidney allografts. PMID- 9365702 TI - Factors affecting risk of relapse and leukemia-free survival in HLA-identical sibling marrow transplant recipients with leukemia. PMID- 9365704 TI - An experimental model of chronic kidney allograft rejection under triple-drug treatment in the rat. PMID- 9365705 TI - Mycophenolate mofetil monotherapy significantly decreases the immune response of acute rejection in rat liver allografts. PMID- 9365706 TI - Effect of immunosuppression on obliterative lesions in a heterotopic large-animal bronchial allograft model. PMID- 9365707 TI - Xenotransplantation of pig organs transgenic for human DAF: an update. PMID- 9365708 TI - In vivo 31P MRS evaluation of the rejection process and differences in anesthetic procedures in a concordant xenotransplantation: mouse heart to rat modell. PMID- 9365709 TI - Effect of FK506 on magnesium homeostasis after renal transplantation. PMID- 9365710 TI - Anamnestic cancer: how long should the cancer-free interval be before renal transplantation? PMID- 9365711 TI - Combined liver and kidney transplantation against a positive cross match in a patient with multispecific HLA-antibodies. PMID- 9365712 TI - [Colorectal cancer: a better known and better treated disease?]. PMID- 9365713 TI - [Role of first-line palliative chemotherapy in metastatic colorectal cancer]. AB - The prognosis of metastatic colorectal cancer remains poor. The 5-year survival rate is indeed 0 to 7%. The median survival duration is 8 months in patients without disease-related symptoms, and 6 months in patients with disease-related symptoms. The true benefit of palliative chemotherapy to increase the overall survival, and the symptom-free survival, has been largely discussed. In patients with disease-related symptoms, combinations of 5 fluoro-uracil (5-FU) and a biomodulator (leucovorin or methotrexate) have demonstrated a benefit on overall survival. In patients with asymptomatic disease, the advantage of systematic chemotherapy is more debatable. Two randomized studies have recently demonstrated that early chemotherapy yielded increased overall survival, disease-free symptom survival, and quality of life. Consequently, in patients with metastatic colorectal cancer, palliative chemotherapy must be performed even at early stages, before the onset of disease-related symptoms. Several regimens can be used as first line chemotherapy. In patients with good general status, and patients in whom a further resection of metastatic tumors could be possible, intensive regimens seem to be more appropriate. In the other patients, 5-FU-based regimens or raltitrexed can be proposed. Generally, the "standard" first line regimen seems to currently be LV5FU2 (bolus and continuous infusion of 5FU and leucovorin). PMID- 9365714 TI - [Role and value of oxaliplatin in metastatic colorectal cancers]. AB - Oxaliplatin is a new cytotoxic drug, with a mechanism of action nearly similar to that of cisplatin. However, in vitro and in vivo studies showed an interesting activity in colorectal cancer. This article summarizes the main data available for patients with advanced colorectal cancer concerning phase I studies, pharmacokinetic, single agent phase II studies, combinations with 5-fluorouracil (5-FU), and tolerance. 10% response rate in second-line therapy, 20 to 25% in first-line, and 26 to 45% in combination with 5-FU in second-line have been reported. The limiting toxicity is a reversible sensitive neuropathy. Oxaliplatin combined with 5-FU should be considered as one of the best therapeutic options in second-line colorectal cancer patients. Further studies will indicate the role of oxaliplatin in less advanced disease, such as metastatic first-line or adjuvant therapy. PMID- 9365715 TI - [Modulation of 5-fluorouracil with folinic acid in advanced colorectal cancers. Groupe d'etude et de recherche sur les cancers de l'ovaire et digestifs (GERCOD)]. AB - The rational of leucovorin modulation of 5-fluorouracil and the clinical results in colorectal cancer are reviewed with special emphasis on the monthly schedule of low dose leucovorin and 5FU bolus for 5 consecutive days (NCCTG-Mayo Clinic regimen) and the bimonthly schedule of high-dose leucovorin and 5FU bolus plus continuous infusion for two consecutive days (LV5FU2) which is now considered as a new standard. PMID- 9365716 TI - [Recent advances in adjuvant chemotherapy in colonic cancers]. AB - Carcinoma of the large bowel is one of the most common malignant disease. In France, 15,000 died each year from the metastatic or locoregional progression of this cancer. In the past, effective surgical adjuvant therapy has been an elusive goal with no evidence of benefit from chemotherapy or immunotherapy. However, a meta-analysis published in 1988 showed that one-year adjuvant chemotherapy using 5-fluorouracil (5-FU) containing regimens may slightly improve survival. Accelerated progress has been made since 1990: in colon cancer with regional nodal metastasis (stage C tumor), therapy with combined 5-FU and levamisole has resulted in a 33% reduction in the death rate. Controlled clinical trials demonstrated improved tumor response rates when the combination of 5-FU and leucovorin was compared with single-agent 5-FU in patients with metastatic colorectal cancer. Recent results indicate that this combination is effective in preventing tumor relapse and improving survival in patients with high risk colon cancer (especially stage C tumor). The comparison of 5-FU and leucovorin to 5-FU and levamisole is ongoing; the preliminary results of these controlled trials showed that 6 months of adjuvant therapy with 5-FU and leucovorin is as effective as the standard 12 months 5-FU and levamisole regimen and less toxic. No clear adjuvant benefit has been established in patients with Dukes' stage B2 colon cancer. The lack of statistical power of the trials and the 80% overall survival rate of these patients may explain these negative results. Almost all the specialists of these tumors considered that it is possible to select patients who are at sufficiently high risk of recurrence so that treatment can be justified. These patients are those who presented initially with tumor perforation or obstruction, adherence to or invasion of adjacent organs, young patients. Clinical trials suggest a survival benefit from the direct portal administration of the 5-FU in the immediate post-operative period, although the magnitude of the effect is less than that seen in the systemic therapy trials. PMID- 9365717 TI - [Colonic cancer: from molecular diagnosis to diagnostic and therapeutic procedure]. AB - Studies of tumour cell genetic alterations have demonstrated the existence of two distinct groups of colorectal cancers. The first one is characterised by the existence of hyperploid tumour cells and frequent loss of heterozygosity. These colorectal cancers are the most common. The second one is characterised by the presence of microsatellite instability. Among the most frequent genetic alterations, the loss of heterozygosity on the short arm of chromosome 17 and the long arm of chromosome 18 seems to be indicators of a pejorative prognosis. In the same way the existence of a p53 mutation in tumour cells has been demonstrated as an independent prognostic factor in colorectal cancer. The indication of an adjuvant chemotherapy on the basis of such genetic alterations remains to be demonstrated by randomised trials. PMID- 9365718 TI - [Precariousness and internal medicine]. PMID- 9365719 TI - [Prevalence of clinical manifestations of allergic reactions in HIV infection. Cross sectional study of 115 subjects]. AB - A cross sectional survey was set up to study the relation between the prevalence of allergic-type reactions during HIV infection course. For each patient, a standardized interview about recent allergic-type manifestations (RATM), skin prick-tests to six common airborne allergens, IgE serum level were done. Among the 115 included patients, the mean CD4 lymphocyte count (CD4) was 214.7/mm3 (range: 0-1328/mm3). RATM were found in 8.8% of patients with CD4 < 50, in 30% of patients with CD4 between 51 and 200, in 36% of patients with CD4 between 201 and 350 and in 11.5% of patients with CD4 < 350 (p = 0.03). The risk of presenting RATM was 4.8 times (95% confidence interval = 1.7-13.5) higher in patients with CD4 between 51 and 350 than in other patients (p = 0.003). The proportion of positive prick-tests did not significantly vary according to the level of CD4. The increased frequency of RATM in patients with CD4 between 51 and 350/mm3 could be due to an allergic predisposition acquired during the course of HIV infection. The mechanisms explaining the reduced frequency of allergic manifestations when immunodeficiency is profound (CD4 < 50/mm3) remain to be explained. PMID- 9365721 TI - [Tobacco smoking and cardiovascular risk]. AB - Cigarette smoking is firmly established as a risk factor for coronary heart disease, stroke and peripheral vascular disease, and is associated with increased cardiovascular mortality. A possible explanation for this relation is that smoking increases the development of atherosclerosis. Indeed, tobacco smoking has been associated with modified lipids levels, decreased fibrinolysis, increased fibrinogen levels and changes in endothelial and platelet functions for instance, which are themselves either known risk factors for or early features of atherosclerosis. Passive smoking, defined as the the involuntary exposure of non smokers to tobacco combustion products in the indoor environment is now convincingly linked to heart disease mortality and morbidity. Stopping smoking works, decreasing cardiovascular mortality and morbidity within 5 years, whatever the age and sex of the previous smoker. PMID- 9365720 TI - [Value and limitations of pulmonary scintigraphy/venous duplex Doppler echography in the management of pulmonary embolism]. AB - PURPOSE: To assess the accuracy of diagnostic strategy of pulmonary embolism (PE) based on clinical examination, lung scan and venous duplex US findings. METHODS: 1,819 patients have been included in a prospective study (mean age: 66, range: 6 102, F 54% H 46%) over a 13 month period. RESULTS: To decide the opportunity of anticoagulant therapy, lung scan alone is decisive in 30.6% of the cases. When taking into account clinical examination, lung scan and venous duplex US findings in a combined diagnostic strategy, a therapeutic decision can be made for 74.2% of the patients. The decisive characteristics of this strategy were influenced by two factor: age (therapeutic decision can be reached for 83% of the patients aged 30 to 50 vs 65% when they are over 85, p < 0.01); history of heart or pulmonary disease (therapeutic decision reached in 62% of the cases with history vs 78% without, p < 0.01). CONCLUSION: Pulmonary angiography seems theoretically necessary in less than 26% of the patients with suspected PE when they have undergone lung scan and venous duplex US. In this case, and when these strategies are not very decisive, it would be important to assess the diagnostic value of spiral CT scanning. PMID- 9365722 TI - [Iodine and thyroid function]. AB - Iodine is a raw material for the thyroid production of hormone which is on the major external control of TSH. The thyroid adaptation to iodine deficiency consists in an increasing iodine concentration from the circulation, an enhancing iodination of the tyrosyl residues in thyroglobulin, a decreasing iodine storage associated to a better recycling of non hormonal iodine and thyroid hyperplasia to provide more synthetic possibilities. Genetic variation and environmental factors explain the wide variation of individuals response to iodine deficiency resulting in a high prevalence of goiter, a mild TSH level increase or overt hypothyroidism. At long term iodine deficiency may have severe pathological consequences and induce neuropsychological deficits in school-children. A policy of iodine supplementation mainly by iodized salt must be undertaken in many areas in the world. Effects of an iodine excess on thyroid function are variable depending upon the underlying thyroid disorder and ambient iodine intake. The most subjects remain euthyroid by mechanisms of autoregulation based on an inhibition of thyroid hormone synthesis and a decrease in the thyroid iodide trap. Euthyroid individuals from high iodine intake areas or those with a history of lymphocytic thyroiditis, treated Graves' disease or subtotal thyroidectomy develop hypothyroidism. On the other hand iodine induced hyperthyroidism is more common in areas of iodine deficiency and in older patients with nodular goiter. PMID- 9365723 TI - [Equilibrium disorders and neuropathy associated with serum anti-Mag activity]. AB - We report the case of a 65 year-old man with a dysglobulinemic neuropathy associated with anti-Mag antibodies. Central (cerebellar) or peripheric (proprioceptive) origin of the gate disorder are discussed. PMID- 9365724 TI - [Bisalbuminemia disclosing primary hyperparathyroidism with fistulized pancreatic false cyst]. AB - Discovery on a protein electrophoregram of a bisalbuminemia can orientate according to its migration fast or slow to an hereditary mutation of an amino acid, or an acquired form by excess of beta lactamines due to renal insufficiency or by the rupture of a pancreatic pseudocyst in the peritoneum. This is this late mechanism that we report in this case of bisalbuminemia related to an opened pancreatic pseudocyst secondary to an adenoma of the parathyroid gland. PMID- 9365725 TI - [Common variable immunodeficiency and total villous atrophy regressive after gluten-free diet]. AB - A patient with a commun variable immunodeficiency (CVID) is hospitalized for chronic symptoms of malabsorption (weigh loss and diarrhea). The duodenal histology show a total villous atrophy. Investigations are negative and a gluten free diet is given. Symptoms of malabsorption disappear and improvement is histologically confirmed. Our observation suggest that the coincidence of gluten sensitive enteropathy and CVID is possible and clinicians should be aware of this association and should consider giving a gluten free diet. The sensitivity of serologic testing in this conditions is unknown. PMID- 9365726 TI - [Rheumatoid purpura and intravenous immunoglobulins]. AB - Henoch-Schonlein purpura is a vasculitis usually with a benign course. Abdominal symptoms occur in 70% of cases, with possible intussusception or intestinal perforation. There is no clear evidence of the efficacy of a treatment in complicated cases of Henoch-Schonlein purpura. Corticosteroids improve abdominal pain but they do not have any effect on renal involvement or prevention of relapses. Intravenous immunoglobulins have been efficient in some cases with recurrent abdominal symptoms or progressive renal lesions. We report the case of a 19-year-old patient with severe abdominal involvement and early renal manifestations of Henoch-Schonlein disease, rapid and sustained improvement was obtained by intravenous immunoglobulins given during 48 hours. PMID- 9365727 TI - [Paralyzing sciatica of central origin]. PMID- 9365729 TI - [Association of primary Gougerot-Sjogren syndrome and Sweet syndrome. Apropos of a case]. PMID- 9365728 TI - [Antiandrogen withdrawal syndrome in hormone refractory metastatic prostate cancer]. PMID- 9365730 TI - [Anicteric cholestasis during Steinert disease]. PMID- 9365731 TI - [Post-partum autoimmune hypophyseal thyroiditis]. PMID- 9365732 TI - [Hematopoietic growth factors, a dilemma for the clinician]. PMID- 9365733 TI - [Venous thromboembolic complications following air travel. Retrospective study of 40 cases recorded in Martinique]. AB - Thromboembolic events following air travel do occur, and have been reported several times in the literature. The authors report a high frequency of these incidence in their geographical region. A retrospective study of 40 cases of phlebitis or pulmonary embolism associated with air travel was conducted over the last 6 years. Cases were analyzed based on the following criteria: sex, age, duration of flight, latency period, diagnostic signs, way of discovery, date of diagnosis and thrombus localisation. The authors analyse these data and underline the main causes of these incidence, with an emphasis on the specific climatic factors in their region. Special attention is placed on the fact that these may occur in young individuals with no previous medical history. The authors conclude by suggesting preventive measures, including general measures and the use of anticoagulants. PMID- 9365734 TI - [Clinical and therapeutic aspects of spontaneous pneumothorax in human immunodeficiency virus infection: 9 cases]. AB - Spontaneous pneumothorax in HIV infected patients are mostly due to a sub-pleural necrotizing pneumonitis most often related to Pneumocystis carinii pneumonia. From our experience of nine patients and a review of the literature, we describe the clinical characteristics and therapeutic management and confirm the frequent failure of simple chest tube drainage and the high morbidity and mortality rate despite treatment. An aggressive stepped-care management of thoracoscopic talc poudrage as initial therapy should be evaluated. PMID- 9365735 TI - [Physiopathology of Raynaud phenomenon: current data]. AB - Despite over a century of investigation, the pathophysiology of Raynaud's phenomenon remains an enigma. The two main theories of the cause of digital artery vasospasm are increased activity of the sympathetic nervous system and a local fault in the digital vasculature. An increased sensitivity and/or concentration of alpha-2 adrenoreceptors is suggested. The activation of serotoninergic receptors may play a role in the maintenance of vasospasm. The recently discovered increase in the vasoconstrictive peptide endothelin-1 and the quantitative deficit in the potent vasodilating calcitonin gene-related peptide may lead to a better understanding of vasospasm mechanisms and open the field for new therapeutical approaches to Raynaud's phenomenon. PMID- 9365736 TI - [Multifocal motor neuropathy: an individualized disease of the peripheral nervous system]. AB - Multifocal motor neuropathy is a peripheral nervous system disease described among chronic inflammatory demyelinating polyneuropathies. It is characterized according to both clinical criteria, including chronic asymmetric and multifocal deficit which starts and remains prominent in the upper limbs, and electrophysiological criteria, including persistent multifocal motor conduction blocks in motor nerves. High titers of serum antiganglioside GM1 antibodies are discovered in nearly 40% of cases. Steroids and plasma exchange are not efficient. High doses of intravenous immunoglobulins (i.v.Ig) improved symptoms in the majority of open and controlled published studies. The quality of the response to i.v.Ig may worsen in some patients after a variable number of infusions, leading to immunosuppressive treatments mainly with oral or intravenous cyclophosphamide. Its etiology is unknown but the frequent presence of anti-GM1 antibody high serum titers, the pathological findings in some rare morphological studies, and the response to i.v.Ig favor the hypothesis of an autoimmune disorder. PMID- 9365737 TI - [Still disease]. AB - Adult onset Still's disease is a systemic disorder of unknown etiology. The diagnosis is difficult and based upon Yamaguchi's criteria after exclusion of infectious diseases, hematologic process or autoimmune diseases. Clinical manifestations are various. Functional prognosis depends essentially on articular involvement. Vital prognosis depends on either hepatic failure or hematological or infectious complications, or amyloidosis. Ferritinemia is an important biological parameter which is not included in current criteria. Treatment is not well codified but steroids represent the most efficient therapy to control fever and systemic manifestations. Search for new treatments and specific markers of adult onset Still's disease are needed. PMID- 9365738 TI - [Horton disease disclosed by a specific inflammatory arteriopathy of the lower limbs]. AB - The authors report the case of a woman aged 67 years who presented an acute ischemia of the lower limbs. A surgical exploration showed no atherosclerosis or thrombus. A biopsy of the femoral artery found an extensive mononuclear cell infiltration of the media and a fragmentation of internal elastic lamina. The diagnosis of Horton disease was considered and confirmed by the presence of clinical signs of polymyalgia rheumatica and inflammatory syndrome (erythrocyte sedimentation rate: 75 mm). Corticosteroid therapy was started with success. A year after discharge there was no recurrence of ischemic manifestations and the erythrocyte sedimentation rate was normal. Involvement of lower limbs in Horton disease is rare and exceptionally proven. But postmortem studies indicate that it is more frequent than previously reported. The diagnosis should be considered in the differential diagnosis of any unexplained case of peripheral vascular disease occurring in the middle-aged or elderly. PMID- 9365739 TI - [Dilated cardiomyopathy and selenium deficiency in AIDS. Apropos of a case]. AB - Cardiac-related death of HIV-positive patients is not rare. The etiology of AIDS associated dilated cardiomyopathies often remains unknown, even at autopsy. We report an observation associated to a severe deficit in selenium. The patient had been diagnosed as HIV-positive 2 years before. He presented Pneumocystis carinii pneumonia then Cryptococcus meningitis. Two months later he was hospitalized for pancreatitis and cachexia. He presented global heart failure that lead to death. No microorganism was found in myocardium at autopsy but plasma selenium was dramatically decreased (24 micrograms/L). The deficit in selenium has been associated to a dilated cardiomyopathy in non-AIDS patients. HIV-positive patients have an early decrease in plasma selenium, this concentration is dramatically decreased in malnourished patients. Selenium deficit might be the cause of some of the AIDS-related dilated cardiomyopathies and selenium supplementation might be useful in these patients. PMID- 9365740 TI - [Neuromeningeal sites of multiple myeloma: 3 cases and review of the literature]. AB - Neurologic manifestations are not unusual in multiple myeloma. Conversely meningeal and cerebral involvement have been very rarely reported. We report here on three patients with multiple myeloma and meningeal or cerebral involvement (two of them with autopsy study): one case of cerebellar involvement associated with secondary plasma cell leukemia and two cases of meningeal involvement. We reviewed the characteristics of 20 cases of meningeal involvement with demonstration of plasma cells at cerebrospinal fluid analysis (18 previously reported cases and our two patients). Meningeal involvement occurs in patients with initially stage III multiple myeloma in 85% of cases and is associated with the occurrence of plasma cell leukemia in 20% of cases. The most frequent neurologic signs are: confusion (60%), altered consciousness (25%), gait disorder (25%), cranial nerve palsy (25%). Meningismus is rarely present. Diagnosis is based on cerebrospinal fluid analysis after lumbar puncture which should be made after cranial magnetic resonance imaging. The diagnosis of intra-cranial haemorrhage and infectious meningitis have to be cautiously ruled out. Despite treatments (systemic and/or intrathecal chemotherapy, radiation therapy), prognosis is very poor: mean time of survival after the occurrence of neurologic signs is about 2 months. PMID- 9365741 TI - [Paraneoplastic intestinal pseudo-occlusion and sensory neuronopathy disclosing small-cell bronchial cancer]. AB - This report describes a case of paraneoplastic neurological syndrome associating a subacute sensory neuronopathy and an intestinal pseudo-obstruction in a 64-year old man with a small cell lung cancer. Various paraneoplastic neurological syndromes have been described in association with small cell lung cancer. In our patient anti-Hu antibodies were identified by indirect immunohistochemistry and western-blot analysis. This antibody constitutes an informative tool in assessing the paraneoplastic origin of neurologic symptoms when the etiological inquiry is negative. Its positivity is important in promoting the search for an underlying malignancy and should lead to repeat investigations if the first investigations are normal. PMID- 9365742 TI - [Haematopoietic growth factors and solid tumors]. AB - Haematopoietic growth factors are glycosylated proteins involved in the differentiation of pluripotent stem cells into committed progenitor cells, which eventually give rise to distinct haematopoietic cell lineages. Three recombinant hematopoietic growth factors--G-CSF, GM-CSF and erythropoietin--are currently commercially available for clinical use. G-CSF and GM-CSF are lineage-specific growth factor that regulate the production and function of granulocytic and monocytic cells. They have been shown to reduce the incidence of febrile neutropenia. Primary prophylactic administration is reserved for patients in which the expected incidence of febrile neutropenia is greater than 40% without haematopoietic growth factor. After a documented occurrence of febrile neutropenia in an earlier cycle, the secondary prophylactic administration of G CSF or GM-CSF may be considered. However, in the absence of clinical data supporting maintenance of chemotherapy dose-intensity, dose reduction should be considered as an alternative to the use of haematopoietic growth factors. G-CSF and GM-CSF also shorten the period of neutropenia in patients undergoing high dose chemotherapy with autologous bone marrow support. Erythropoietin is currently approved for treatment of anemia associated with cisplatin-based chemotherapy with the aim to reduce transfusion requirements. PMID- 9365743 TI - [Economic evaluation of the use of haematopoietic factors in managing malignant hemopathies]. AB - Economic evaluation of haematopoietic growth factors in the treatment of malignant hemopathies was undertaken along with clinical trials or retrospectives studies. The cost of the sole treatment was estimated to be 2,302 US$ per cycle. Cost-minimization analyses compared the cost of a treatment course (chemotherapy, bone marrow transplantation with and without haematopoietetic growth factors), and cost-effectiveness analyses estimated the cost per episode of averted febrile neutropenia. Results appear to be contradictory and do not allow definite conclusions about the existence of extra costs or of cost savings due to the introduction haematopoietetic growth factors, except in the case of filgrastim mobilized peripheral blood progenitor cell transplantation. PMID- 9365744 TI - [Hematopoietic growth factors in the treatment of malignant hemopathies]. AB - The authors analyze the role of G-CSF and GM-CSF in hematological malignancies. These allow correction of drug-induced neutropenias and perhaps more importantly allow the increase of doses of chemotherapy to improve the antitumor effect, and permit the maintenance of full chemotherapy doses in elderly patients. They can also mobilize peripheral blood stem cells for autologous and recent allogeneic transplantation. They can be useful at low doses in correcting the spontaneous neutropenia of bone marrow failures. A specific antitumor effect, on the other hand, is extremely hypothetical. Erythropoietin by contrast has been disappointing in the treatment of anemia in spontaneous bone marrow failures. For the treatment of thrombocytopenias, preliminary results with thrombopoietin are encouraging. Combinations of growth factors will probably improve results obtained with one factor. However, in all cases the cost/benefit of growth factors will have to be strictly established. PMID- 9365745 TI - [A deceptive electrophoresis]. PMID- 9365746 TI - [Apropos of a protein profile]. PMID- 9365747 TI - [Acute pericarditis after vaccination against hepatitis B: a rare effect to be known]. PMID- 9365748 TI - [Systemic scleroderma and sarcoma of the mesentery]. PMID- 9365750 TI - Longitudinal follow-up comparison of educational interventions: multimedia textbook, traditional lecture, and printed textbook. AB - RATIONALE AND OBJECTIVES: The goal of this prospective, interinstitutional study was to compare the long-term instructional effectiveness of a pediatric multimedia textbook (MMTB) to that of a standard lecture and a printed textbook. MATERIALS AND METHODS: A randomized cohort of 89 3rd-year medical students from two institutions were initially evaluated from June 1992 to June 1993 and reevaluated in May 1994. Students were randomly assigned to one of four instructional groups: computer-aided instruction by means of MMTBs (n = 21), traditional lecture (n = 23), printed textbook (n = 19), and a control group (n = 26). After instruction, all groups were tested by means of a multiple choice test at the end of their pediatric clerkship; they were given this same test 11-22 months later. RESULTS: The long-term instructional effectiveness of the MMTB, printed textbook, and lecture were the same as that in the control group, as determined by analysis of variance of mean test scores. CONCLUSION: The educational advantage of MMTBs observed immediately after instruction was not detected 1 year later. Because attrition reduced statistical power, further research is necessary to determine how educational fading affects these instructional formats. PMID- 9365749 TI - Local reactions after injection of iodinated contrast material: detection, management, and outcome. AB - RATIONALE AND OBJECTIVES: The authors assessed the frequency, sequelae, and risk factors of extravasation of intravenously administered iodinated contrast media. MATERIALS AND METHODS: All patients with local reactions after intravenous injection of contrast media between November 1994 and December 1996 were studied. Comparison was made with data obtained from a control group of 100 patients with no local reactions who underwent contrast material-enhanced computed tomography (CT). RESULTS: Local reactions were reported in 56 (0.25%) of 22,254 patients who received intravenous injections of iodinated contrast media. Fifty-one patients experienced extravasation, and five patients experienced local irritation in the absence of clinically detectable extravasation. Extravasation occurred during CT (n = 46), urography (n = 4), and venography (n = 1). Contrast material was nonionic in 37 cases and conventional ionic in 14 cases of extravasation. Extravasated volumes exceeded 30 mL in 22 patients and 100 mL in six patients. Forty-five (80%) of 56 patients with local reactions had complete resolution of symptoms within 24 hours. Only four patients had symptoms for more than 48 hours. No surgery was required. Compared with the control group, patients with extravasation were significantly more likely to have been injected with small bore catheters (21 or 22 gauge) and to have been injected at low or high rates. CONCLUSION: Symptoms of contrast medium extravasation usually resolve quickly. In patients with extravasation, injections are more likely to have been performed with techniques that vary from normal practice. PMID- 9365752 TI - Resident learning and knowledge retention from resident-prepared chest radiology conferences. AB - RATIONALE AND OBJECTIVES: The authors assessed resident learning and retention of knowledge from resident-prepared chest radiology conferences. MATERIALS AND METHODS: Radiology residents presented five chest conferences to their peers during a 5-month interval; the conferences were modeled on a case presentation format. Tests were given 5 minutes before each conference (pretest) and immediately after each conference (posttest). The tests were readministered as a final examination 6 months later, at which time the residents were asked to evaluate the conference format. RESULTS: Conference attendance ranged from six to 11 residents. Mean posttest scores were statistically significantly higher than mean pretest scores (P < .0001). Six-month retention scores were higher than pretest scores (P < .05) but lower than posttest scores (P < .05). On a scale of 1-6, with 1 representing strongly disagree and 6 strongly agree, residents strongly agreed that the conferences provided an excellent learning experience (mean score, 5.27). CONCLUSION: Resident-prepared conferences are effective for teaching residents chest radiology. Resident testing at 6 months demonstrated retention of knowledge above pretest levels but lower than posttest levels. PMID- 9365751 TI - Digital mammography: computer-assisted diagnosis method for mass detection with multiorientation and multiresolution wavelet transforms. AB - RATIONALE AND OBJECTIVES: The authors evaluated a modular computer-assisted diagnosis (CAD) method for mass detection that uses computation of features in three domains (gray level, morphology, and directional texture). Their objectives were to improve the sensitivity of detection and reduce the false-positive (FP) detection rate. MATERIALS AND METHODS: The directional wavelet transform (DWT) method, which uses both multiorientation and multiresolution wavelet transforms to improve image preprocessing and segmentation of suspicious areas and to extract both morphologic and directional texture features, was evaluated with a previously reported image database containing 50 normal and 45 abnormal digitized screen-film mammograms. The mammograms contained all mass types and included 16 minimal cancers. This method was compared with the Markov random field (MRF) method to avoid issues related to case selection criteria. Free-response receiver operating characteristic curves were compared for both DWT and MRF methods. RESULTS: For the DWT method, the sensitivity was 98% and the FP detection rate was 1.8 FP findings per image. For the MRF method, the sensitivity was 90% and the FP detection rate was 2.0 FP findings per image. CONCLUSION: The CAD method applied to the full mammographic image is automatic and independent of mass type. The segmentation of masses as performed with this method may potentially allow visual interpretation according to American College of Radiology criteria. PMID- 9365753 TI - Relationship between contrast enhancement and diagnostic accuracy with the liver specific CT contrast medium FP 736-04 in an experimental model of liver metastases. AB - RATIONALE AND OBJECTIVES: The authors sought to establish the optimal level of liver enhancement at computed tomography (CT) with a hepatocyte-specific contrast medium in an experimental model of liver metastases. MATERIALS AND METHODS: Anesthetized nude rats (n = 18) injected intraportally with cells from human colonic adenocarcinoma and Sprague-Dawley rats (n = 11) without metastases were used. A fractional intravenous infusion of contrast material was given in escalating doses up to a total of 4.0 mL per kilogram of body weight. Mean attenuation of the liver was calculated for each accumulated dose, and the overall detection rate was determined on a lesion-by-lesion basis. Sensitivity, specificity, and positive and negative predictive values were also established for each dose. RESULTS: Liver metastases were diagnosed with increasing reliability for enhancement values of up to 30.0 HU +/- 5.2 (mean +/- standard deviation), which corresponded to a dose of 0.5 mL/kg. CONCLUSION: In this model, optimal reliability in the diagnosis of liver metastases with CT was achieved at an enhancement value of approximately 30 HU. PMID- 9365754 TI - Computer-assisted measurement of lumbar spine radiographs. AB - RATIONALE AND OBJECTIVES: The authors evaluated a method for obtaining reproducible, reliable measurements from standard lumbar spine radiographs for determining the degree of spondylolisthesis, vertebral body height, intervertebral disk space height, disk space angle, and degree of vertebral body wedging. MATERIALS AND METHODS: Four to six easily defined points were identified on each vertebral body on anteroposterior and lateral plain radiographs of the lumbosacral spine of patients. From these points, the degree of spondylolisthesis, the vertebral body height, the intervertebral disk space height, the disk space angle, and the degree of vertebral body wedging were easily calculated by using well-known geometric relationships. This method requires the use of a personal computer and a standard spreadsheet program but does not require the use of any other specialized radiographic equipment, computer hardware, or custom software. RESULTS: Calculations of intra- and interobserver variability for the measurement of spondylolisthesis, disk space height, disk space angle, and vertebral body height measurement showed that the technique is extremely reproducible. CONCLUSION: This technique may prove useful in the prospective evaluation of potential candidates for lumbar spinal stenosis surgery. PMID- 9365755 TI - Educating interventional radiology personnel in nonpharmacologic analgesia: effect on patients' pain perception. AB - RATIONALE AND OBJECTIVES: The purpose was to evaluate the effects on patients' pain perception of educating interventional radiology personnel in nonpharmacologic analgesia. MATERIALS AND METHODS: Ninety-six patients undergoing lower-extremity arteriography or percutaneous nephrostomy were asked to rate the pain they experienced during the procedure on a scale of 0 to 5 (0 = no pain, 1 = mild pain, 2 = moderate pain, 3 = severe pain, 4 = very severe pain, 5 = worst pain possible). Patients were studied at two baseline sessions (baseline 1, December 1993 to August 1994, n = 15; and baseline 2, September 1995 to January 1996, n = 11) and after the staff underwent one of two training sessions (posttraining 1, January 1995 to July 1995, n = 34; posttraining 2, January 1996 to April 1996, n = 36). Training targeted nurses and technologists and included rapport skills, correct use of language and suggestions, distraction, relaxation training, and self-hypnosis. Data were evaluated with analysis of variance for repeated measures. RESULTS: The mean pain scores reported after training were lower (1.48) and matched an "acceptable" pain score of 1.52 more closely than those reported under baseline conditions (2.54, P = .001). There was a tendency toward reduced use of intravenously administered agents for conscious sedation after training. There were no statistically significant differences in the pain scores between patients who underwent arteriography and patients who underwent nephrostomy overall (1.76 and 1.78, respectively), at baseline (2.58 and 2.43, respectively), and after staff training (1.49 and 1.42, respectively). CONCLUSION: Interventional radiology personnel trained in nonpharmacologic analgesia methods can help reduce patients' pain perception during interventional procedures. PMID- 9365756 TI - Assessment of the pulmonary structure-function relationship and clinical outcomes measures: quantitative volumetric CT of the lung. PMID- 9365757 TI - HIV partner notification: taking a new look. PMID- 9365758 TI - Secondary colony formation after long-term bone marrow culture using peripheral blood and bone marrow of HIV-infected patients. AB - OBJECTIVE: To determine if defective bone marrow function in HIV infection is associated with decreased numbers of progenitor cells or defective stromal cell function. DESIGN: Defective bone marrow function may in part be responsible for the cytopenias so frequently seen in patients with AIDS. Although a number of investigators have reported impaired growth of committed hematopoietic progenitor cells in HIV-1-infected patients, few studies have examined the most primitive hematopoietic stem cells. Our study was designed to determine the function and quality of the most immature hematopoietic progenitor and stem cells in the peripheral blood and bone marrow of HIV-1-infected patients and to assess stromal cell function. METHODS: For quantification of these cells we used a modified long term culture-initiating cell (LTCIC) assay in which the number of secondary colony-forming cells after 5 weeks of stromal culture served as a measure of LTCIC. Stromal cells from normal controls and HIV-1-infected patients were used for cross-matching experiments. Normal CD34+ cells or those derived from HIV infected patients were plated and colony growth assessed. RESULTS: We found that HIV-1-infected patients had a mean of 0.8 secondary colony-forming cells/10(5) peripheral blood mononuclear cells (PBMC), whereas normal controls showed 1.2 secondary colony-forming cells/10(5) PBMC (P = not significant) after long-term culture. Asymptomatic patients showed well preserved numbers of secondary colony forming cells after long-term culture of PBMC, but a significant reduction was seen in patients with a history of opportunistic infections (P < 0.01), low CD4+ cell count (< 200 x 10(6)/l; P < 0.05), or leukopenia (P < 0.05). Decreased numbers of secondary colony-forming cells have also been found in bone marrow of HIV-1-infected patients with advanced disease. When normal CD34+ cells were cultured on stromal layers from bone marrow of HIV-1-infected patients or normal controls, no differences in the numbers of surviving progenitor cells were found. CONCLUSIONS: Our data indicate that the hematopoietic defect in HIV-1 infection involves the most immature hematopoietic cells and becomes evident in advanced disease. Stromal function of HIV-infected patients appears normal. PMID- 9365759 TI - Infection of Macaca nemestrina neonates with HIV-1 via different routes of inoculation. AB - OBJECTIVES: Receptive anal intercourse but not orogenital sex has been identified as a major risk factor for transmission of HIV-1. Recent studies using simian immunodeficiency virus (SIV) in rhesus macaques have demonstrated relatively efficient infection following oral administration, indicating that modes of transmission may vary between HIV-1 and SIV. Here, we investigate whether HIV-1 infection of macaques via the oral route is more efficient than via the rectal route. DESIGN: Eleven Macaca nemestrina neonates were exposed to HIV-1 via different routes (four oral, two intravenous, and five rectal). One animal was orally inoculated with a sham inoculum and two control animals were not exposed. METHODS: All animals were followed for virological signs of infection, and for pathogenesis associated with HIV-1 infection by general physical examinations, complete blood cell counts and lymphocyte subset analysis, and full necropsies. RESULTS: Three out of five rectally exposed macaques and both of the intravenously inoculated animals became infected with HIV-1, whereas none of the orally exposed animals showed evidence of HIV-1 infection. Clinical observations following exposure included failure to thrive in the orally inoculated animals and low CD4/CD8 ratios in the rectally exposed macaques. CONCLUSIONS: The finding that, contrary to what has been reported for SIV, transmission of HIV-1 via the oral route is not more efficient than via the rectal route, indicates important biological differences between HIV-1 and SIV, with direct implications for the spread of HIV and associated AIDS, and for development of anti-HIV-1 vaccines. PMID- 9365760 TI - Lymphoproliferative immune function in the Sydney Blood Bank Cohort, infected with natural nef/long terminal repeat mutants, and in other long-term survivors of transfusion-acquired HIV-1 infection. AB - OBJECTIVES: To assess T-helper cell immune function (proliferation) in members of the Sydney Blood Bank Cohort (SBBC) compared with other individuals with transfusion- and sexually acquired HIV-1 infection and with matched HIV-negative controls. DESIGN AND METHODS: Decreasing CD4 counts and T-helper cell function are associated with disease progression. Peripheral blood mononuclear cells (PBMC) from study subjects were assayed for in vitro proliferative responses to HIV-1-derived antigens, recall antigens and alloantigen. T-helper cell function and CD4 counts in members of the SBBC were followed longitudinally. RESULTS: Proliferative responses and CD4 counts from members of the SBBC were similar to or better than those of other transfusion- or sexually-acquired HIV-1-positive long-term non-progressors (LTNP), including the HIV-negative matched SBBC control groups. However, individuals with disease progression had reduced or undetectable proliferative responses to recall antigens but a conserved response to alloantigen; they also had low CD4 counts and low CD4:CD8 ratios. In the SBBC, these immune parameters were usually stable over time. CONCLUSIONS: The unique SBBC with natural nef/long terminal repeat deletions in the HIV-1 genome were genuine LTNP without showing signs of disease progression. They appeared to be a group distinct from the tail-end of the normal distribution of disease progression rates, and may remain asymptomatic indefinitely. The SBBC virus may form the basis of a live attenuated immunotherapeutic or immunoprophylactic HIV vaccine. PMID- 9365761 TI - HIV-1 detection in cervicovaginal secretions during pregnancy. AB - OBJECTIVE: To assess the reproducibility of and factors associated with HIV detection in cervicovaginal secretions (CVS). DESIGN: Longitudinal study of 43 HIV-1-infected pregnant women in Paris. METHODS: HIV DNA was detected in peripheral blood mononuclear cells (PBMC) by Amplicor and gag nested polymerase chain reaction (PCR) assays. The HIV genotype was determined by heteroduplex mobility assay. Amplicor and gag nested PCR assays were performed on serial CVS samples for HIV DNA detection, and the HIV Monitor test was used for HIV RNA detection in plasma and CVS. RESULTS: A total of 144 CVS samples were collected from the women included in the study. HIV-1 DNA was detected in 36 (25%) of the 144 samples, from 16 (37.2%) of the 43 women. Results of HIV-1 DNA detection were concordant in the first two samples in 27 (84.4%) of the 32 women with at least two CVS samples. The last CVS sample collected in each woman was HIV-1 DNA positive in 13 (30.2%) of the 43 women. Three factors were found to be independently associated with HIV-1 DNA detection in CVS: HIV-1 subtype B, absence of zidovudine therapy, and microbial cervicovaginal infection. HIV RNA was detected in CVS from 10 (23.3%) out of 43 women and correlated with DNA detection in the same sample and HIV RNA detection in plasma. CONCLUSIONS: DNA and RNA PCR can be used to detect HIV in cells and supernatants of CVS. These techniques may be useful in cohort studies to investigate HIV transmission and to evaluate the efficacy of antiretroviral drugs to reduce HIV excretion. PMID- 9365762 TI - Pulmonary and extrapulmonary tuberculosis at AIDS diagnosis in Spain: epidemiological differences and implications for control. AB - OBJECTIVE: To ascertain the differential factors associated with pulmonary versus extrapulmonary tuberculosis (TB) at AIDS diagnosis in Spain. DESIGN: Analysis of AIDS surveillance data. METHODS: Data about AIDS patients, aged 12 years and over, diagnosed in 1995 were taken from the Spanish AIDS Register. The respective proportions of cases presenting with pulmonary and extrapulmonary TB at AIDS diagnosis were analysed by gender, age, HIV transmission category, prison record, province, country of origin and CD4+ lymphocyte count. A multivariate analysis was carried out using logistic regression analysis. RESULTS: Of 6161 AIDS cases analysed, 20.1% presented with pulmonary TB and 20.4% with extrapulmonary TB. Overall, TB showed association with men, age under 30 years, injecting drug users (IDU), cases of heterosexual HIV transmission, and concurrent or past stay in prison. Frequency of TB proved no different among foreign-born patients. Pulmonary and extrapulmonary TB showed a similar distribution for most of the variables. Current prison inmates registered a high risk of pulmonary TB [adjusted odds ratio (OR), 4.2; 99% confidence interval (CI), 3.1-5.8] compared with patients without prison record, and ex-prison inmates registered an intermediate risk (OR, 2.3; 99% CI, 1.8-3.0). Among patients with TB at AIDS diagnosis, pulmonary TB was associated with subjects currently in prison (OR, 2.1; 99% CI, 1.5-3.0) and injecting drug use (OR, 1.5; 99% CI, 1.0-2.4). Pulmonary TB presented with higher CD4+ lymphocyte counts than extrapulmonary TB (P < 0.001). CONCLUSIONS: The results suggest the importance that recent transmission of TB may be having among young adults, IDU and prison inmates in particular, and calls for a review of control strategies. PMID- 9365763 TI - Mucosal abnormalities in microsporidiosis. AB - OBJECTIVE: To determine the prevalence of microsporidiosis in HIV-infected patients with and without diarrhoea and to characterize alterations in mucosal architecture and brush border enzyme activities in patients with microsporidiosis. PATIENTS: A total of 259 HIV-infected patients undergoing oesophago-gastroduodenoscopy because of diarrhoea (n = 123) or other symptoms (n = 136) were studied. METHODS: Patients were evaluated for the presence of microsporidia by electron microscopy of duodenal biopsies. Brush border enzyme activities were measured by histochemistry and mucosal architecture was determined by three-dimensional morphometry in biopsies from patients with microsporidiosis and compared with biopsies from a subgroup of HIV-infected patients with or without other enteropathogens. RESULTS: Enterocytozoon bieneusi was detected in 17 patients and Encephalitozoon intestinalis was detected in two patients. Microsporidiosis was significantly more frequent in patients with chronic diarrhoea (19.1%; P < 0.0001) or in patients with acute diarrhoea (7.2%; P = 0.04) than in patients without diarrhoea (1.5%). Microsporidiosis was associated with lactase deficiency (P = 0.03) and a reduced activity of alkaline phosphatase (P = 0.028) and alpha-glucosidase (P = 0.025) at the basal part of the villus compared with brush border enzymes in patients without enteropathogens. Patients with microsporidia had reduced villus height (P = 0.043) and a villus surface reduced by 40% (P = 0.004) compared with patients with enteropathogens other than microsporidia. CONCLUSIONS: Our study confirms the association between microsporidia and diarrhoea. The pathophysiologic mechanism by which microsporidia cause diarrhoea appears in part to be malabsorption, caused by a reduction of absorptive mucosal surface and impairment of enterocyte function. PMID- 9365764 TI - In vitro transendothelial migration of blood T lymphocytes from HIV-infected individuals. AB - OBJECTIVE: We hypothesized that differential extravasation of circulating CD4+ or CD8+ T lymphocytes contributes to HIV-associated CD8+ lymphocytic alveolitis. Differences in T-cell transendothelial migration may be intrinsic or emerge at sites where vascular endothelium is activated by overexpression of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma. DESIGN: We used an in vitro model of lymphocyte extravasation to assess transendothelial migration of peripheral blood mononuclear cells (PBMC) from HIV-positive individuals. We assayed bronchoalveolar lavage (BAL) fluid from HIV-positive and normal individuals to determine if increased levels of TNF-alpha and IFN-gamma were present in the lungs of HIV-infected individuals. METHODS: Transendothelial migration was assessed by determining the number and flow cytometric phenotype of PBMC adherent to or migrating across unstimulated or TNF-alpha and IFN-gamma-activated endothelial cell monolayers. We measured BAL fluid cytokine concentrations using standard antigen-capture enzyme-linked immunosorbent assays for TNF-alpha and IFN gamma. RESULTS: T cells migrating across unactivated endothelial cells were significantly enriched for CD4+ T cells. Cytokine activation of endothelial cells allowed significantly greater transendothelial migration of CD8+ T cells compared to unactivated endothelial cells. TNF-alpha was increased in BAL fluid from HIV positive individuals relative to controls. CONCLUSIONS: These data suggest that, in HIV-positive individuals, CD4+ T cells are migration competent and blood CD8+ T cells do not have enhanced migration competence relative to CD4+ T cells. CD8+ T cell extravasation is aided by TNF-alpha and IFN-gamma-induced endothelial cells activation. PMID- 9365765 TI - Potential efficacy of fumagillin in intestinal microsporidiosis due to Enterocytozoon bieneusi in patients with HIV infection: results of a drug screening study. The French Microsporidiosis Study Group. AB - OBJECTIVE: Intestinal microsporidiosis due to Enterocytozoon bieneusi is a frequent cause of chronic diarrhoea in patients with HIV infection for which there is no available therapy. This study was designed to search for a drug with activity against this organism. DESIGN: Prospective open-labelled Phase II multicentre study. SETTING: University hospitals. PATIENTS: Sixty HIV-infected men with intestinal E. bieneusi infection. INTERVENTIONS: Ten drug regimens were consecutively tested orally for 3 weeks: albendazole plus metronidazole, sulphadiazine plus pyrimethamine, atovaquone, doxycycline plus nifuroxazide, itraconazole, flubendazole, chloroquine, paromomycin, sparfloxacin and fumagillin. Nine evaluable patients per regimen were required, but each patient could be enrolled up to three times in the study. OUTCOME MEASURE: Efficacy was assessed primarily by the clearance of E. bieneusi from stools and intestinal biopsies. The safety of each regimen was also assessed. RESULTS: Only purified fumagillin was able to clear E. bieneusi from stools as well as intestinal biopsies, whereas all other regimens failed to show antiparasitic efficacy. However, only four patients received fumagillin because of drug-induced thrombocytopenia. The four patients who received fumagillin remained free of E. bieneusi infection after a mean follow-up of 10 months. CONCLUSION: Eradication of E. bieneusi from the intestinal tract of patients with HIV infection and persistent immunosuppression is an achievable goal. Our study allowed the identification of oral fumagillin as a potential treatment for intestinal microsporidiosis due to E. bieneusi. PMID- 9365766 TI - Has the rate of progression to AIDS changed in recent years? AB - OBJECTIVES: To investigate whether the rate of progression to AIDS has changed over time by testing an effect of the year of seroconversion on AIDS onset (Centers for Disease Control and Prevention 1987 revised classification), next to an effect of the calendar period of follow-up. DESIGN: French multicentre prospective study of 385 homosexual and heterosexual subjects and 231 subjects from a multicentre study of European injecting drug users (IDU), all with a documented date of HIV-1 seroconversion. METHOD: The effect of the year of seroconversion was compared by the log-rank test. Crude and adjusted relative hazard (ARH) were quantified using the Cox model. Calendar period of follow-up was studied separately for sexual exposure group and IDU and treated as a time dependent variable in a Cox model. RESULTS: In the 616 study subjects the year of seroconversion was not significantly related to AIDS occurrence (n = 108); the ARH was 0.88 [95% confidence interval (CI), 0.56-1.38] for those who seroconverted in 1988-1989, and 1.17 (95% CI, 0.61-2.25) for those who seroconverted after 1989, compared with those who seroconverted before 1988. In the sexual exposure group, a clear trend towards less rapid progression to AIDS was observed in subjects followed in 1991-1992 (ARH, 0.49; 95% CI, 0.24-0.99) and after 1992 (ARH, 0.54; 95% CI; 0.24-1.21), compared with those followed before 1991. This favorable trend was not observed in IDU despite a significant decrease over time of Pneumocystis carinii pneumonia as AIDS-defining illness. Conversely to sexual exposure groups, the frequency of antiretroviral treatment (mainly zidovudine) prescription was still low during the most recent calendar periods in IDU when the CD4 count threshold of 200 x 10(6)/l was reached. CONCLUSIONS: No evidence was found of a change in the rate of progression to AIDS in subjects who seroconverted in recent years. Furthermore, conversely to sexual exposure groups, the lack of favorable trends in IDU users followed in recent years suggest that health-care systems are not always adapted to their lifestyles. PMID- 9365769 TI - Years of potential life lost due to HIV infection in the United States. AB - OBJECTIVE: To compare premature mortality due to HIV infection with that from other causes of death in the United States, so as to provide a basis for allocating public health resources among causes of death that would be more useful than either total or age-specific mortality data. METHODS: Using death certificate data, we calculated years of potential life lost (YPLL) before age 65 years for each cause of death. We defined YPLL for an individual as the difference between 65 years and the age at death if the age was < 65 years, or zero if the age was > or = 65 years. The YPLL in the population was the sum of YPLL for individuals. RESULTS: In 1995, HIV infection was the fourth leading cause of YPLL nationally, accounting for 4.7 YPLL per 1000 population (all under age 65 years; 8.8% of the 53.9 YPLL from all causes per 1000 population). Among males, HIV infection ranked fourth (11.0% of YPLL) nationally and in 1994 was the top cause of YPLL in four states: New York (causing 22.7% of YPLL), Florida (18.1%), New Jersey (17.6%) and Maryland (13.9%); and in 51 cities of > or = 100,000 total population, where it caused 12.6-50.9% of YPLL. In 1995, among females, HIV ranked sixth (4.5% of YPLL) nationally and in 1994 was the leading cause of YPLL in 11 cities (11.6-31.4%). CONCLUSION: HIV infection has become the fourth leading cause of premature mortality, measured in terms of YPLL, in the United States and the leading cause in a sizeable number of United States cities. PMID- 9365767 TI - Risk factors for Kaposi's sarcoma in HIV-positive subjects in Uganda. AB - BACKGROUND: Kaposi's sarcoma (KS) is associated epidemiologically with HIV infection and with human herpesvirus 8 (HHV-8 or KSHV). Both KS and HIV infection are common in Uganda. We conducted a case-control study of 458 HIV-seropositive. Ugandan adults with KS and 568 HIV-seropositive subjects without KS to examine risk factors for HIV-associated KS. METHODS: We recruited newly diagnosed adult KS cases from five hospitals in Kampala, Uganda and controls from a large referral clinic for HIV infection at Mulago Hospital. All cases and controls were counselled and tested for HIV and answered an interviewer-administered questionnaire about their home, socio-economic conditions, lifestyle and sexual behaviour before they became ill. Only HIV-seropositive subjects were included in the analysis. RESULTS: There were 295 males and 163 females with KS and 227 male and 341 female controls. Age distribution was similar but there was a higher proportion of cases (45%) than controls (29%) residing in rural regions of Uganda. KS cases were more likely than controls to have a higher level of education (X2 for trend, 4.8; P = 0.03), to have occupations associated with affluence [chi 2 for heterogeneity, 17.3 on 5 degrees of freedom (df); P = 0.004] and to come from larger settlements [adjusted odds ratio (OR) for settlements of > 1000 versus 10-99 houses, 1.8; 95% confidence interval (CI), 1.1-3.0]. Cases were more likely than controls to have high household income (chi 2 for trend, 32.6; P < 0.001) and other markers of urban or rural wealth such as owning several cows (chi 2 for trend, 9.5; P = 0.002). Cases were more likely to travel away from home (adjusted OR, 1.6; 95% CI, 1.1-2.3) and more likely to have spent increasing time in contact with water (chi 2 for trend, 12.3; P < 0.001). Few indices of sexual behaviour were related to risk of KS, including reported number of sexual partners. Cases were more likely than controls to be married to one rather than several spouses (adjusted OR, 1.6; 95% CI, 1.2-2.2) and to have reported a history of sexually transmitted diseases (STD) (adjusted OR, 1.6; 95% CI, 1.2-2.3). CONCLUSIONS: Among HIV-infected subjects, KS cases are characterized by better education and greater affluence, compared with controls. Urban address, travel away from home, exposure to water, monogamous marriage and self-reported STD were also more frequent among KS cases than controls. The higher socio-economic status of persons with HIV and KS may be a marker for enhanced exposure to a possibly sexually transmitted agent, or for a delayed exposure to a childhood infection. The risk posed by exposure to water among KS cases requires further study. PMID- 9365768 TI - Breastfeeding by HIV-1-infected women and outcome in their infants: a cohort study from Durban, South Africa. AB - BACKGROUND: Women in developing countries have the difficult choice of balancing the risk of transmitting HIV through breast milk against the substantial benefits of breastfeeding. It is not known, however, whether the benefits of breastfeeding are the same when the mother is HIV-infected. Therefore, we examined the impact of breastfeeding on infections, growth and mortality in the infants of HIV-1 infected women. METHODS: Infants of HIV-1-positive women were followed from birth and at each visit they were examined, growth parameters were recorded and notes were made of feeding method, and of current and interim illnesses. RESULTS: Of the 43 HIV-infected and 90 non-infected infants for whom feeding data were available, 36 infants (27%) were exclusively breastfed, 76 (57%) received mixed feeding, and 21 (16%) received formula only. The HIV transmission rate was 39% in those exclusively breastfed, 24% in those fed exclusively on formula and 32% in those receiving mixed feeding [relative risk (RR), 7.39; 95% confidence interval (CI), 1.67-32.6 between the exclusive breast and formula only groups]. There was a stepwise increase in the transmission rate with duration of exclusive breastfeeding of 1, 2 and 3 months (45%, 64%, and 75%, respectively). Of the infected infants, seven (50%) exclusively breastfed, 13 (51%) of those on mixed feeds and none on formula only developed AIDS; exclusively breastfed infants had a slower rate of progression to AIDS (mean age, 7.5 months versus 5.0 months, P = 0.2242) than those on mixed feeds. Mortality (which occurred in the infected infants only) was 19% in the exclusively breastfed infants; 13% in those on mixed feeds and 0% in those exclusively formula-fed. The frequency of failure to thrive and episodes of diarrhoea and pneumonia were not significantly different between the three groups in both the infected and non-infected infants. CONCLUSIONS: Exclusive breastfeeding by HIV-infected women does not appear to protect their infants against common childhood illnesses and failure to thrive, nor does it significantly delay progression to AIDS. The implication of the trend towards differential mortality rates according to feeding groups is uncertain and requires further investigation. PMID- 9365770 TI - Changes in AIDS incidence for men who have sex with men, United States 1990-1995. AB - OBJECTIVES: To describe changes in AIDS incidence for men who have sex with men (MSM) from 1990 to 1995, by demographic and geographic groups. METHODS: We examined national AIDS surveillance data reported up to 30 September 1996, for men who received AIDS diagnoses in the years 1990-1995 and whose only reported risk behavior was sex with men. We evaluated trends in AIDS rates by estimating the incidence of clinical AIDS (AIDS defined by opportunistic illnesses), and report clinical AIDS incidence rates for MSM (AIDS rates) and proportional change in rates from 1990 to 1995. RESULTS: Clinical AIDS rates (MSM per 100,000 men per year) increased by 12% from 25.5% in 1990 to 28.5% in 1995. Significant variations in AIDS rates and 5-year changes in AIDS rates were observed in various subgroups of MSM. Five-year increases in AIDS rates were highest for American-Indian/Alaskan native (53%), black (45%), and Hispanic (23%) MSM; the only decrease occurred for white MSM (-2%). Incidence for black MSM increased from twofold (in 1990) to threefold (in 1995) the rate for white MSM. Large increases in AIDS rates were observed for MSM in rural areas (34%) and areas with 50,000 to 249,999 residents (34%) and for MSM aged over 60 years (32%). CONCLUSIONS: The high national AIDS rate for MSM continued to rise, but more slowly than earlier in the epidemic. Racial/ethnic minority MSM had consistently large increases in AIDS rates; AIDS rates decreased only slightly for white MSM. The AIDS epidemic among MSM is not homogenous, and AIDS rates continue to increase for minority MSM, and MSM living in rural areas. HIV prevention remains a high priority for all MSM, especially black and Hispanic MSM. PMID- 9365771 TI - Investigating temporal changes in the rate of HIV progression: challenges and limitations. PMID- 9365772 TI - HIV-1 neurocognitive disorders and chemokine receptors. PMID- 9365773 TI - Increased hyperglycaemia during cotreatment with pentamidine and corticosteroids in AIDS patients. PMID- 9365774 TI - Complete remission of AIDS-related Kaposi's sarcoma associated with undetectable human herpesvirus-8 sequences during anti-HIV protease therapy. PMID- 9365775 TI - Rapid decay of HIV RNA in the cerebrospinal fluid during antiretroviral combination therapy. PMID- 9365776 TI - Portal vein thrombosis in patients receiving indinavir, an HIV protease inhibitor. PMID- 9365777 TI - Remission of AIDS-associated intestinal microsporidiosis with highly active antiretroviral therapy. PMID- 9365778 TI - Acute cytomegalovirus infection in AIDS patients with CD4 counts above 100 x 10(6) cells/l following combination antiretroviral therapy including protease inhibitors. PMID- 9365779 TI - Acceptability and feasibility of a clinical trial to assess the efficacy of a microbicide-containing vaginal gel to prevent HIV infection among female sex workers in Abidjan, Cote d'Ivoire. PMID- 9365780 TI - AIDS survival in patients contaminated by heterosexual contacts: French Guiana, 1992-1995. PMID- 9365781 TI - HIV-1 transmission across the vaginal epithelium. PMID- 9365782 TI - DNA haplotypes of the complement C6 and C7 genes associated with deficiencies of the seventh component; and a new DNA polymorphism in C7 exon 13. AB - Eight common DNA polymorphisms have been described for the linked C6 and C7 genes. We now describe a ninth polymorphism in C7 exon 13 which is located in a tight cluster with two previously reported markers. We have used all these markers to investigate the heterogeneity of C7 deficiency. Five of the nine C7 deficient probands (resident in Ireland, South Africa, Russia and Israel) are heterozygous for C6/C7 haplotypes. Seven different C7 deficient haplotypes were found for C7 markers alone, but all the four Israelis share one and three out of four Irish haplotypes share another. The markers appear to be a good guide to the heterogeneity of C7 deficiency and have been useful in choosing homozygous subjects for the investigation of molecular defects. PMID- 9365783 TI - Cloning and evaluation of RALGDS as a candidate for the tuberous sclerosis gene TSC1. AB - RALGDS is a 115 kDa protein which was identified by its ability to enhance guanine nucleotide exchange for the ras family member ral. It also binds to activated ras and rap1, and appears to function as part of a signalling complex in downstream events following rap1 activation. Here we report the identification of full-length cDNA clones for human RALGDS, isolated from a brain cDNA library. The predicted protein has strong sequence homology to rat and murine isoforms of RALGDS in the N- and C-terminal regions, but an internal region (aa 250-380) shows relatively high divergence with only 42% identical amino acid residues. The human RALGDS gene is contained within a 30 kb region of 9q34, approximately 200 kb proximal to the ABO gene, within the current critical region for the tuberous sclerosis gene TSC1. Partial genomic structure was determined; it consists of at least 11 exons. Based upon analysis of Southern blots from 110 TSC patients, genomic DNA SSCP analysis, and RT-PCR analysis which demonstrated RNA expression of both alleles in patients from 9q34-linked TSC families using intragenic polymorphisms, we conclude that RALGDS is not likely to be TSC1. PMID- 9365785 TI - Use of siblings as controls in case-control association studies. AB - The transmission disequilibrium test (TDT) is a simple means to detect association which should only be positive if the marker allele is linked to the disease locus, but it cannot be used if parents of affected subjects are unavailable, as can occur when the disease has a late age of onset. Although one can sometimes deduce parental genotypes using the siblings of affected cases, reliance on this procedure can introduce bias and may also result in discarding many families which could provide useful information. Instead, it is shown that the use of unaffected siblings as controls is, like the TDT, robust against bias due to population stratification and other sources, and is expected only to produce positive results when a marker is both associated and linked with the disease locus. The method can have much less power than a case-control study using unrelated controls, but this can be guarded against by seeking unaffected siblings which are genotypically distinct from cases and by focusing only on alleles which are different within pairs of cases and controls. This yields a pair-wise test for association which can be used for multiallelic markers in a manner exactly analogous to the extended TDT (ETDT). The use of siblings as controls is simple, robust, practical and worthy of further consideration. PMID- 9365784 TI - Genetic contribution of the HLA region to the familial clustering of coeliac disease. AB - In order to assess the effect of the HLA region on familiality of coeliac disease (CD), we carried out a study on 121 CD index cases and 325 first degree relatives. The transmission disequilibrium test confirmed the importance of the HLA-DR3 haplotype in CD susceptibility. However, the different distortion found in affected children inheriting maternal or paternal DR3 alleles suggested that the sex of the parent might influence the risk conferred by this haplotype. The increase in risk to siblings of affected individuals relative to the risk in the general population (lambda s) and the contribution of the HLA genes to this clustering (lambda sHLA) have also been estimated. Non-overlapping data from the literature have been collected and combined with our sample to extend such analysis. Then, the percentage contribution of the HLA region to the development of CD among siblings was 36.2%. This result confirms that the HLA genotypes are an important genetic background to CD development but shows that additional susceptibility factors remain to be identified. PMID- 9365786 TI - A likelihood ratio test for detecting patterns of disease-marker association. AB - A likelihood ratio test of disease-marker association is proposed, based on the observation of marker alleles transmitted from parents to affected children. The proposed association test has the advantage of identifying the population pattern of disease-marker association, differentiating between marker alleles that are positively and negatively associated with the disease. The power of the test for detecting association is evaluated and compared with three existing multi-allelic tests for some specific disease-marker association patterns. The power of the parametric tests depends crucially on the pattern of disease-marker association. An over-parameterised association model is less detrimental in terms of power than an under parameterised model. PMID- 9365787 TI - The sib-pair problem. I. Affected pairs with parents. Constant penetrance models. AB - Affected sib pairs with typed but unaffected parents, conveniently termed foursomes, have become a major source of information on genetic susceptibility to common disease. So far most methods of analysis have been based on extensions of the single locus analyses developed, and successfully applied, to the mendelian disorders. However, unifactorial methods are not suited to multifactorial disorders. The power of methods of detecting linkage in the presence of more than one locus with one or more susceptibility alleles is considered. The relevance of familial clustering to predicting the presence of loci with susceptibility or resistance alleles sufficiently frequent and effective to have an appreciable influence on population incidence is discussed. The mathematical problem of clustering due to numerous alleles of small effect was resolved by Pearson in 1901 in relation to claims that the mendelian model of an allele at a single locus determining a distinct phenotype was necessary to explain the familial concentrations that had been observed in several species. The apparent inconsistency between the mendelian and polygenic models was resolved by Fisher's demonstration in 1918 that there was no essential difference between these two extreme forms of phenotypic determination. Although constant penetrance models are unrealistic, and no longer necessary since Pearson's analysis, the assumption is implicit in most recent analyses and has the advantage of simplicity in providing a lower limit on the sample sizes necessary. PMID- 9365788 TI - Linkage of microsatellites to the AGXT gene on chromosome 2q37.3 and their role in prenatal diagnosis of primary hyperoxaluria type 1. AB - Defects in the AGXT gene mapped to chromosome 2q37.3 cause primary hyperoxaluria type 1 (PH1), one of the inherited disorders of endogenous oxalate overproduction. In order to identify diagnostically useful linkage markers in this region of chromosome 2 we have typed three microsatellite loci mapping to the q37 region of chromosome 2 in 192 individuals from 30 families. They were additionally studied for mutations and polymorphisms in the AGXT gene. Maximum lod scores of 29.1, 22.8 and 15.8 were obtained for D2S140, D2S125 and D2S395 respectively at recombination fractions (theta) of 0.001, 0.015 and 0.02. Confidence intervals for recombination as determined by the 'lod-1 rule' were 0.015, 0.05 and 0.06. Three recombinants were identified between AGXT and D2S125/D2S395, whereas no recombination between AGXT and D2S140 was observed. These data allow the calculation of the risk of incorrect prenatal diagnosis of PH1 based solely on linkage analysis with these extragenic markers. PMID- 9365789 TI - Alpha coat protein COPA (HEP-COP): presence of an Alu repeat in cDNA and identity of the amino terminus to xenin. AB - We previously sequenced the 4333-nucleotide cDNA of the COPA (HEP-COP) gene which encodes the human homologue of the alpha-subunit of the coatomer protein complex, involved in intracellular protein transport. Within the 3' untranslated region at nucleotides 4049-4333 was observed an Alu repeat containing conserved A and B block elements, and showing high homology to the human Alu-Sx subfamily consensus sequence. Upstream of the Alu repeat were noted a TATA box, a CAAT motif and two activating transcription factor (ATF)-like binding sites, which represent putative regulatory elements directing Alu transcription. In addition, the 25 and 35 N-terminal amino acid residues of COPA and its bovine homologue were identical to xenin-25 and proxenin, respectively. Xenin-25 is a gastrointestinal hormone that stimulates exocrine pancreatic secretion. This peptide is related to xenopsin, neurotensin and neuromedin N which are bioactive peptides derived from larger precursors via proteolytic cleavage by cathepsin E at processing sites determined by conserved C-terminal sequences, i.e. proline/valine-X-X-hydrophobic amino acid. Given the conformity of the C-terminal residues of xenin-25 (PWIL) and of its progenitor molecule, proxenin (VIQL), it is proposed that these peptides are generated by a similar mechanism of post-translational modification involving a parent precursor represented by the alpha-subunit of coatomer. PMID- 9365790 TI - Assignment of the human cardiac/slow skeletal muscle troponin C gene (TNNC1) between D3S3118 and GCT4B10 on the short arm of chromosome 3 by somatic cell hybrid analysis. AB - We have determined the chromosomal location of the human cardiac/slow skeletal muscle troponin C gene (TNNC1) to the short arm of chromosome 3 using somatic cell hybrids. PCR-based analysis of a 'monochromosomal' hybrid panel identified the presence of the TNNC1 gene on human chromosome 3 and subsequent analysis of the Genebridge4 radiation hybrid panel located the gene between D3S3118 (7.3cR) and GCT4B10 (4.2cR) with a lod score of > 3.0. PMID- 9365792 TI - Pulmonary nodule resection during lung volume reduction surgery. AB - Lung volume reduction surgery (LVRS) and concomitant pulmonary nodule resection can improve the respiratory function of and remove malignant lesions in patients with chronic obstructive pulmonary disease and lung cancer. Previously, using standard selection criteria, some patients with emphysema who also had lung nodules were denied surgery because of the severity of their pulmonary dysfunction. In this article, the authors report improved pulmonary function in 11 patients with severe emphysema who underwent combined LVRS and nodule resection. PMID- 9365793 TI - Responsibilities of the preoperative holding area nurse. AB - The preoperative holding area is an important, but often over-looked, area in the surgical suite. This area, however, is where the majority of surgical patients and their family members have their first direct contact with perioperative staff members. The preoperative holding area can provide the environment for calming, informative interactions that should help patients prepare for their surgical procedures. The preoperative holding area nurse's primary responsibility is to provide information and emotional support for patients and their family members, to ensure that all preoperative data have been accumulated, and to maintain patients' baseline hemodynamic statuses. PMID- 9365794 TI - An alcohol and drug education program for nurses. AB - Alcohol and drug use and abuse present serious problems for health care professionals, both as clinicians and abusers. These topics, however, have not been addressed adequately in nursing curricula. Nurses need to know the effects that alcohol and drug use and abuse have on individuals, families, and society. In this article, the authors outline the framework for a course or presentation that reviews the problems and applies the nursing process to the issues. The course can be adapted to meet the needs of nurses in any discipline, including the perioperative area, as well as for other health care providers and community groups. Course content and teaching strategies are included. PMID- 9365795 TI - Self-efficacy enhanced preoperative instruction. AB - Perioperative nurses traditionally have helped patients cope with the adversities of surgery through preoperative instruction. The authors conducted a study to determine whether an efficacy-enhancing preoperative teaching protocol was effective in increasing preoperative self-efficacy in patients scheduled to undergo laparoscopic cholecystectomy procedures with general anesthesia. The subjects were 60 surgical patients in a 156-bed community hospital located in the midwestern United States. Analysis of covariance indicated there were no significant differences between groups after controlling for preoperative self efficacy. Further research is needed to determine whether an efficacy-enhancing teaching protocol can improve selected short- and long-term outcomes in surgical patients. PMID- 9365796 TI - The risks and challenges of surgical glove failure. AB - The relationship between infection control standards and surgical gloving practices is an important issue in combating infectious disease. For their own and their patients' protection, health care personnel must rely on the barrier qualities of gloves more than ever before. Both surgical and examination gloves fail frequently, which puts health care providers and patients at risk of acquiring fluid-borne pathogens. This paper discusses current guidelines, the risk of infection by viral and bacterial pathogens, controversial issues involving gloving practices, and recommendations to improve infection control practices. PMID- 9365797 TI - Development and implementation of a perioperative assistant training program. AB - Due to health care reform, many institutions have had to examine the way they deliver patient care. This article describes how, in response to this challenge, an interdisciplinary OR team at North Shore University Hospital, Manhasset, NY, developed and implemented the role of perioperative assistant in the OR. The authors describe the education curriculum for program completion, along with specific results. The program's difficulties and challenges are described, as well as what was learned as the program proceeded. The authors stress that program implementation depended on the efforts of all staff members, their willingness to help develop the perioperative assistant role, and their ability to function as a team. PMID- 9365798 TI - Professional collaboration includes recognition of every surgical team member's role. PMID- 9365799 TI - Genetic polymorphism of drug metabolising enzymes in African populations: implications for the use of neuroleptics and antidepressants. AB - Metabolism of most drugs influences their pharmacological and toxicological effects. Drugs particularly affected are those with a narrow therapeutic window and that are subjected to considerable first-pass metabolism. Much of the interindividual and interethnic differences in effects of drugs is now attributable to genetic differences in their metabolism. Genetic polymorphisms have been described for many drug-metabolising enzymes in Caucasian and Oriental populations, the most well-characterised being those for cytochrome P450 2D6, cytochrome P450 2C19, glutathione S-transferases, and N-acetyl transferase 2. African populations have been studied to a lesser extent, but it is apparent that populations within Africa are heterogeneous with respect to these polymorphisms. In addition, although some allelic variants are common to all populations throughout the world (e.g., CYP2D6*5), some allelic variants are specific for an African population (e.g., CYP2D6*17). The polymorphisms give rise to enzymes with changed or no activity towards drug substrates. Two of the most important enzymes for metabolism of neuroleptics and other psychoactive drugs are CYP2D6 and CYP2C19. This article compares the current information on polymorphisms of these two enzymes in African and other populations and discusses the implications of these polymorphisms for neuropharmacotherapy. PMID- 9365800 TI - Evaluation of risk factors for Alzheimer's disease in elderly east Africans. AB - A number of biological risk factors have been implicated for Alzheimer's disease (AD). The investigation of prevalence rates of AD in crosscultural populations has much potential in validating these factors. We previously assessed brain amyloid beta (A beta) protein deposition and other lesions associated with AD as possible markers for preclinical AD in elderly nondemented East Africans. In further analysis, we demonstrate that 17-19% of elderly East African subjects without clinical neurological disease exhibited neocortical A beta deposits and minimal neurofibrillary changes at necropsy that was qualitatively and quantitatively similar to that in an age-matched elderly control sample from Cleveland, OH. A beta deposits varied from numerous diffuse to highly localized neuritic plaques and were predominantly reactive for the longer A beta 42 species. In parallel studies, we evaluated another recently implicated factor in AD, the apolipoprotein E genotype. We found relatively high frequencies of the apolipoprotein E-epsilon 4 allele in elderly nondemented East Africans. The frequencies were comparable to those in other African populations but higher than in subjects from developed countries. Our limited study suggests that elderly East Africans acquire cerebral lesions found in AD subjects but the apolipoprotein E-epsilon 4 allele may not be a highly specific factor for the disease among East Africans. PMID- 9365801 TI - Neurobiology of cerebral malaria and African sleeping sickness. AB - This review is aimed at emphasizing the need for basic neuroscience research on two tropical diseases, malaria and sleeping sickness (African trypanosomiasis), that still represent major health problems and in which severe involvement of the nervous system is frequently the direct cause of death. The life cycles of the two parasites, the protozoan Plasmodium and Trypanosoma brucei, which are the causative agents of malaria and sleeping sickness, respectively, are briefly reviewed. The historical contribution to the pathogenesis and therapy of malaria by a renowned pioneer in neuroscience, Camillo Golgi, is pointed out. The different strategies for survival in the host by the intracellular Plasmodium and the extracellular African trypanosomes are summarized; such strategies include sites favorable for hiding or replication of the parasites in the host, antigenic variation, and interactions with the cytokine network of the host. In particular, tumor necrosis factor-alpha and interferon-gamma may play a role in these infections. The parasites may paradoxically interact with cytokines to their benefit. However, cytokine receptors are expressed on neuronal subsets sensitive to cytokine action, and stimulation of these subsets may cause neuronal dysfunctions during the infections. Finally, the clinical symptoms of cerebral malaria and African trypanosomiasis and research aiming at deciphering their pathogenetic mechanisms that could affect the nervous system at a molecular level are described. The need for neuroscientists in this endeavor is emphasized. PMID- 9365802 TI - Plasma luteinizing hormone levels in response to gonadotropin-releasing hormone agonist and clonidine in Trypanosoma congolense-infected female goats. AB - Trypanosomiasis, a parasitic disease of humans and animals, occurs over a wide area of Africa and imposes a large socioeconomic burden on the people. In the present study, we investigated whether trypanosomiasis-induced reproductive disorders were due to pituitary or hypothalamic dysfunction by determining plasma luteinizing hormone (LH) response to gonadotropin-releasing hormone (GnRH) agonist or clonidine in Trypanosoma congolense-infected female goats. With GnRH agonist administration, the total amount of LH secreted over a 140-min sampling period on day 23 and day 60 postinfection was consistently higher (71 and 21%, respectively) in infected goats compared to controls. In contrast, clonidine administration to infected goats on day 28 and day 69 postinfection failed to significantly alter the LH pulse frequency or the mean LH pulse amplitude over a 80-min sampling period. The results, especially the lack of response to clonidine, indicate that trypanosomiasis impairs GnRH release from the hypothalamus. PMID- 9365803 TI - Localization of M1 muscarinic receptors in rat brain using selective muscarinic toxin-1. AB - Mambas, African snakes of the genus Dendroaspis, produce several types of toxins that are of pharmacological interest. The novel muscarinic toxin-1 (MT-1), from the green mamba Dendroaspis angusticeps, binds specifically to muscarinic M1 receptors in homogenates of rat cerebral cortex. Iodination of the toxin, 125I muscarinic toxin-1 (125I-MT-1), renders the toxin selective for M1 muscarinic receptors. Quantitative measurement of 125I-MT-1 autoradiography in rat brain sections indicated highest labeling in the nucleus accumbens, striatum, and dentate gyrus. High densities of 125I-MT-1 binding sites were located in the CA1 region of the hippocampus, frontal, and parietal cortices. Moderate densities of binding sites were seen in temporal cortex, and hippocampal subregions CA2, CA3, and CA4, whereas low labeling was observed in the cerebellum and spinal cord. PMID- 9365804 TI - Ibogaine and a total alkaloidal extract of Voacanga africana modulate neuronal excitability and synaptic transmission in the rat parabrachial nucleus in vitro. AB - Ibogaine is a natural alkaloid of Voacanga africana that is effective in the treatment of withdrawal symptoms and craving in drug addicts. As the synaptic and cellular basis of ibogaine's actions are not well understood, this study tested the hypothesis that ibogaine and Voacanga africana extract modulate neuronal excitability and synaptic transmission in the parabrachial nucleus using the nystatin perforated patch-recording technique. Ibogaine and Voacanga africana extract dose dependently, reversibly, and consistently attenuate evoked excitatory synaptic currents recorded in parabrachial neurons. The ED50 of ibogaine's effect is 5 microM, while that of Voacanga africana extract is 170 micrograms/ml. At higher concentrations, ibogaine and Voacanga africana extract induce inward currents or depolarization that are accompanied by increases in evoked and spontaneous firing rate. The depolarization or inward current is also accompanied by an increase in input resistance and reverses polarity around 0 mV. The depolarization and synaptic depression were blocked by the dopamine receptor antagonist haloperidol. These results indicate that ibogaine and Voacanga africana extract 1) depolarize parabrachial neurons with increased excitability and firing rate; 2) depress non-NMDA receptor-mediated fast synaptic transmission; 3) involve dopamine receptor activation in their actions. These results further reveal that the Voacanga africana extract has one-hundredth the activity of ibogaine in depressing synaptic responses. Thus, ibogaine and Voacanga africana extract may produce their central effects by altering dopaminergic and glutamatergic processes. PMID- 9365805 TI - Experimental study of the anticonvulsant plants used for treatment of infantile convulsion in Nigeria. AB - In Nigeria, convulsion, especially in children, is managed by traditional healers employing plant decoctions. A number of herbs are used for this purpose. We have carried out some preliminary studies on some of these traditional anticonvulsant plants. The experimental models were pentylenetetrazole- and electroshock-induced convulsions in mice. The acute toxicity (LD50) and the median effective (ED50) doses of the extracts of these plants were determined. Most of these plants exhibited potent anticonvulsant activity. The average onset of convulsion was delayed, while the average duration of convulsion was significantly reduced. Most of the animals showed signs of central nervous system depression. The results indicate that these plants possess anticonvulsant property, and this activity may be linked to their ability to depress the central nervous system. PMID- 9365807 TI - Quantitative and topographical study of retinal ganglion cells in the chameleon (Chameleo chameleon). AB - Chameleons display a number of well-described physiological peculiarities of their visual system, but there is no information on the topography of the retinal ganglion cell layer. In the present study, ganglion cell density of the chameleon retina was constructed from whole mounts of the retina stained with cresyl violet. For the identification of ganglion cells, these latter cells were labelled retrogradely with horseradish peroxidase applied to the optic nerve. Using this criterion, the proportion of ganglion cells was estimated to represent 80% of retinal cells, while glial cells and amacrine cells represented 14 and 6%, respectively, of the total cell population of the retina. As for the main features of the retinal map, first, ganglion cells were distributed inhomogeneously within the ganglion cell layer, and revealed the existence of a putative area centralis. Second, a horizontal visual streak, which showed two peak density areas, was identified. These features point out the degree of specialisation of the chameleon retina and the complexity of its visual system. PMID- 9365806 TI - Characterization of opioid peptides and opioid receptors in the brain of jerboa (Jaculus orientalis), a hibernating rodent. AB - The present study was undertaken to investigate the biochemical characteristics of the opioid receptors and opioid peptides in the jerboa (Jaculus orientalis) brain, a subdesert rodent of Morocco. We have demonstrated the presence of delta, mu, and kappa sites in the jerboa brain. The endogenous opioid peptides methionine-enkephalin, beta-endorphin, and dynorphin were evaluated in different physiological states of the animal (active and hibernating). The circulating methionine-enkephalin in different states of the animal (active, hibernating, exposure to cold conditions, and fasting) was evaluated in the plasma. Our results indicate that the hibernating state the opioid receptors level decreased, whereas the concentration of opioid peptides increased. These findings suggest that both opioid receptors and opioid peptides could be involved in the adaptation of the jerboa to survive under thermal stress. PMID- 9365808 TI - Optic disc and optic nerve of the blind cape mole-rat (Georychus capensis): a proposed model for naturally occurring reactive gliosis. AB - Recent studies of the visual system of animal species that live in a subterranean environment show not only regressive but also progressive morphological features. In this regard the aim of the present investigation is to describe the structural organisation of the eye and optic nerve of the adult Cape mole-rat, with special emphasis on both glial cell population and myelination. The main results are: (a) astrocytes show identical features to those occurring in reactive gliosis; (b) optic fibers vary greatly in diameter; (c) very small axons are myelinated and are often surrounded by a thicker sheath than larger optic fibers; (d) a large onion bulb-like structure composed of optic fibers, glia, and ganglion cells is found within the choriocapillary layer. These results suggest that the Cape mole rat and probably other subterranean rodents may serve as a model to study spontaneous gliosis as well as mechanisms involved in myelination and degenerative processes. PMID- 9365809 TI - Neuropeptidergic organization of the suprachiasmatic nucleus in the blind mole rat (Spalax ehrenbergi). AB - The blind mole rat, Spalax, is a subterranean rodent with atrophied, subcutaneous eyes. Whereas most of the visual system is highly degenerated, the retino hypothalamic pathway in this species has remained intact. Although Spalax is considered to be visually blind, circadian locomotor rhythms are entrained by the light/dark cycle. In the present study we used anterograde tracing techniques to demonstrate retinal afferents to the suprachiasmatic nucleus (SCN) and immunohistochemistry to examine the distribution of neuropeptides that are known to be involved in the regulation or expression of circadian rhythmicity. Based on the localization of retinal afferents and neuropeptides, the SCN can be divided into two subdivisions. The ventral region, which receives retinal afferents, also contains vasoactive intestinal polypeptide (VIP)-containing neurons, and fibers that are immunopositive to neuropeptide Y (NPY) and serotonin (5-HT). The dorsal region contains vasopressinergic neurons, but this latter cell population is extremely sparse compared to that described in other rodents. The dorsal region is also characterized by numerous VIP-immunoreactive fibers. The presence of NPY and 5-HT fibers suggests that the SCN receives afferent projections from the intergeniculate leaflet and from the raphe nuclei, respectively. These neuroanatomical results, together with previous studies of behavior, visual tract tracing, and immediate early gene expression, confirm that an endogenous clock and the capacity for light entrainment of circadian rhythms are conserved in the blind mole rat. PMID- 9365811 TI - Gordin Kaplan Award Lecture. Building a relationship: science and the community. AB - An appreciation for the intrinsic relationship that exists among science, scientists, and the public must be established. Both practitioners of science and the public should be made more aware that science is part of everyday life and that the definition of a scientist should be more encompassing. It is generally accepted that the public supports but often does not understand the goals of the scientific community. This is often due to lack of effective communication. The scientific community has accepted accountability to the public and attempts have been made to improve our image. Programs by groups and individuals to interact with the public, particularly school children, have grown. However, there is still a need to expand this area. It is our responsibility to find our niche in science awareness programs as speakers, mentors, or facilitators. Participation in these programs is an essential part of a professional scientist's career and should be encouraged by administration. Interaction with the public improves our ability to explain science in lay terms and the relevance of our work to the community. End points should be established to measure success: not just numbers of students entering "scientific" careers but also science literacy. Developing this strategy will not only improve the image of the scientific community with the public but also build a lasting relationship where needs and aspirations will be mutually appreciated. PMID- 9365810 TI - The use of seismic signals by fossorial southern African mammals: a neuroethological gold mine. AB - Behavioral adaptations exhibited by two African fossorial mammals for the reception of vibrational signals are discussed. The Namib Desert golden mole (Eremitalpa granti namibensis) is a functionally blind, nocturnal insectivore in the family Chrysochloridae that surface forages nightly in the Namib desert. Both geophone and microphone recordings in the substrate suggest that the golden mole is able to detect termite colonies and other prey items solely using seismic cues. This animal exhibits a hypertrophied malleus, an adaptation favoring detection of low-frequency signals. In a field study of the Cape mole-rat (Georychus capensis), a subterranean rodent in the family Bathyergidae, both seismic and auditory signals were tested for their propagation characteristics. This solitary animal is entirely fossorial and apparently communicates with its conspecifics by drumming its hind legs on the burrow floor. Auditory signals attenuate rapidly in the substrate, whereas vibratory signals generated in one burrow are easily detectable in neighboring burrows. The sensitivity to substrate vibrations in two orders of burrowing mammals suggests that this sense is likely to be widespread within this taxon and may serve as a neuroethological model for understanding the evolution of vibrational communication. Neuroethological implications of these findings are discussed. PMID- 9365812 TI - The 1996 Merck Frosst Award. The voltage-sensitive release mechanism: a new trigger for cardiac contraction. AB - Contraction in mammalian heart is initiated by a rapid rise in intracellular free calcium (Ca2+) triggered by excitation of the sarcolemma. Traditional views of cardiac excitation-contraction coupling have focused on the importance of Ca(2+) induced Ca2+ release from the sarcoplasmic reticulum as a major source for this increase in Ca2+. Influx of Ca2+, primarily through L-type Ca2+ channels and the sodium-calcium (Na(+)-Ca2+) exchanger, is considered to be the main trigger for Ca(2+)-induced Ca2+ release. However, we recently have discovered a new trigger for excitation-contraction coupling in experiments on isolated ventricular myocytes under voltage clamp conditions. This trigger is a voltage-sensitive release mechanism that initiates release of Ca2+ from the sarcoplasmic reticulum. This article reviews the development of the concept of voltage-activated Ca2+ release in heart and discusses the importance of this discovery to the physiology, pathophysiology, and pharmacology of cardiac contraction. PMID- 9365813 TI - Tyrosine kinase inhibitor, genistein, inhibits macroscopic L-type calcium current in rat portal vein smooth muscle cells. AB - The effect of genistein, a specific tyrosine kinase inhibitor, was tested on the slow (L-type) Ca2+ current (ICa(L)) of vascular smooth muscle cells from freshly isolated rat portal vein, using whole-cell voltage clamp. To isolate ICa(L), the pipette contained high Cs+ and the bath contained 140 mM tetraethylammonium (TEA) to block K+ currents. Bath application of genistein decreased ICa(L) in a concentration-dependent manner within 3-6 min. The concentration for half-maximal inhibition (IC50) was 54.9 microM (at a holding potential of -40 mV). At a concentration of 300 microM, genistein produced nearly complete inhibition of ICa(L). The inhibitory effect of genistein was not reversed after washout for up to 5 min. The potential for half-inhibition (V1/2) of the steady-state inactivation curve for ICa(L) was shifted to the left by genistein (10.6 mV at 50 microM), suggesting that genistein exerts a voltage-dependent block. Superfusion with daidzein, an inactive analog of genistein, had no inhibitory effect on ICa(L) at concentrations as high as 300 microM. These results may suggest that the L-type Ca2+ channels in vascular smooth muscle cells are possibly modulated by endogenous tyrosine kinase activity. That is, tonic phosphorylation by tyrosine kinases maintains the Ca2+ channels in an available state for activation by depolarization. Thus, the vascular tone may be controlled by tyrosine kinase activity. PMID- 9365814 TI - Tyrosine kinases modulate the activity of single L-type calcium channels in vascular smooth muscle cells from rat portal vein. AB - In a previous study, we demonstrated that extracellular application of the tyrosine kinase inhibitor genistein produced a dose-dependent inhibition of the macroscopic slow (L-type) Ca2+ currents of vascular smooth muscle (VSM) cells, and that daidzein, an inactive analog of genistein, had no such effect. These results suggested that the L-type Ca2+ channels in VSM cells may be modulated by endogenous tyrosine kinase activity. To confirm and extend those findings, the effect of genistein on the activity of single Ca2+ channels was examined in freshly isolated single VSM cells from rat portal vein, using the cell-attached patch-clamp technique. The pipette solution contained 90 mM Ba2+ as charge carrier and 0.5 microM Bay K 8644 (to enhance basal activity of the channels), and the bath contained 140 mM KCl to "zero" the resting membrane potential. Depolarizing pulses to 0 mV, from a holding potential of -80 mV, elicited inward unitary currents that were blocked by 1 microM nifedipine (n = 6). The slope conductance of the unitary Ca2+ currents gave a value of 21.5 +/- 0.4 pS (n = 9) for the Ca2+ channels. Bath application of genistein (50 microM) did not change the unit amplitude and slope conductance: the conductance in the presence of genistein was 22.2 +/- 0.5 pS (n = 6). However, compared with controls, the activity of single Ca2+ channels was significantly inhibited by genistein in a dose-dependent fashion. The ensemble-averaged currents were decreased by 48.4 +/- 11.2% with 50 microM genistein; 100 microM genistein inhibited the Ca2+ currents by 76.8 +/- 11.8%. The open probability (NPo) was decreased by 50 microM genistein from 0.24 +/- 0.09 to 0.11 +/- 0.07. Single-channel kinetic analysis showed that genistein decreased the mean open time and prolonged the mean closed time. The inhibitory effect of genistein on the Ca2+ channel activity occurred within 3 min, and it could be reversed by washout within 3-5 min. Daidzein, in concentrations up to 300 microM, produced no change in the activity of the single Ca2+ channels. These results demonstrate that genistein inhibits the activity of the L-type Ca2+ channels in VSM cells, suggesting that the availability of the channels for voltage activation may be maintained through tonic tyrosine kinase phosphorylation. PMID- 9365815 TI - Oviduct fluid pH in intact and unilaterally ovariectomized pigs. AB - The pH of the oviduct lumen was measured at different stages of the estrous cycle in the ampulla and ampullary-isthmic junction (AIJ) of intact and unilaterally ovariectomized mated or nonmated pigs. The pH profile consisted of high frequency small peaks superimposed on low frequency large amplitude peaks. One animal examined at midcycle exhibited fluctuations in pH (peak to nadir; delta pH) of 0.3 and 0.7 units in the ampulla and AIJ, respectively, and the frequencies of the large peaks in these regions were 2.6 and 1.6 peaks.min-1, respectively. In six preovulatory unmated pigs, the delta pH (mean +/- SE) was 0.50 +/- 0.04 units in both regions and the large peak frequencies were 0.6 +/- 0.06 peaks.min-1. In one animal that was assessed during ovulation, the pH showed deviations of up to 0.4 pH units, which were probably due to the alkalinity of follicular fluid accompanying the ovulated eggs. In the ampullae of five unilaterally ovariectomized postovulatory-mated pigs, the delta pH in oviducts with and without an ipsilateral ovary was significantly lower than preovulatory (p < 0.05), but the large and the small peak frequencies were not significantly different. By contrast, the delta pH in the AIJ with an ipsilateral ovary (0.11 +/- 0.02 units) was significantly lower than before ovulation (0.54 +/- 0.04 units) and also when compared with the contralateral AIJ (0.36 +/- 0.06 units) (p < 0.05). The ovary also influenced the small peak frequency, which was significantly higher if the ipsilateral ovary was absent (10.7 +/- 1.5 vs. 14.9 +/- 1.6 peaks.min-1, respectively). Thus, oviduct fluid pH is controlled by both systemic and local mechanisms, and the ipsilateral ovary and (or) embryonic factors influence the pH profile of the oviduct. PMID- 9365816 TI - Changes in myocardial density during postinfarction healing: effect on estimation of in vivo left ventricular mass by echocardiographic imaging. AB - To determine whether changes in density (rho) of infarct and noninfarct zones during healing and remodeling after myocardial infarction influence estimates of left ventricular mass and detection of temporal changes by imaging, we measured weights (g) and volumes (mL) of infarct, noninfarct, and mixed tissue in hearts removed 1 to 42 days after anterior infarction in three groups of dogs: nonreperfused infarction treated with placebo or captopril, or infarcts reperfused after 2 h. In vivo mass was calculated from in vivo diastolic myocardial volumes (echocardiograms) and an assumed density of 1.05 g/mL or actual values derived from tissue weights and volumes. Over the 42 days, actual density deviated more from the assumed value of 1.05 in infarct than noninfarct zones, and the overall density was higher for reperfused than nonreperfused ventricles (1.09 vs. 1.06 g/mL, p < 0.01). Correction for density improved the correlation between absolute in vivo and postmortem mass slightly but not the detection of relative changes in mass in control, captopril, or reperfusion groups. These findings suggest that (i) densities of infarct and noninfarct zones differ and change during healing, especially after reperfusion, and (ii) correction for density provides more accurate estimates of volume-derived mass in reperfused hearts. PMID- 9365817 TI - Effects of natriuretic peptides and endothelins on the nerve-evoked release of adenine nucleotides and nucleosides in guinea-pig vas deferens. AB - Two members of the natriuretic peptide family (rANF8-33 and pBNP1-32) and two members of the endothelin family (ET-1 and ET-2) have been studied for their effects on the neurogenically induced overflow of adenosine 5'-triphosphate (ATP), adenosine 5'-diphosphate (ADP), adenosine 5'-monophosphate (AMP), and adenosine (ADO) from the isolated guinea-pig vas deferens. rANF, pBNP, ET-1, and ET-2 each at 10 nM produced a significant increase in the evoked overflow of ATP, by 52, 85, 130, and 115%, respectively. None of the peptides altered the overflow of ADO. ET-1 and ET-2 each caused an increase in the overflow of ADP and AMP by an amount similar to their effects on ATP overflow, so that the ratio ATP:ADP remained 1:1 throughout. Natriuretic peptides, however, affected the overflow of ADP and AMP to a lesser extent than ATP, resulting in an ATP:ADP ratio of 2:1 after rANF and of 1.5:1 after pBNP. In addition, rANF or pBNP, but not ET-1 or ET 2, inhibited ecto-ATPase activity, suggesting that this mechanism may contribute to the facilitatory effect of the natriuretic peptides on the nerve-evoked overflow of ATP in this tissue. PMID- 9365818 TI - Comparison of the cyclooxygenase-1 inhibitory properties of nonsteroidal anti inflammatory drugs (NSAIDs) and selective COX-2 inhibitors, using sensitive microsomal and platelet assays. AB - Two forms of cyclooxygenase (COX) activity are involved in the synthesis of prostaglandins, prostacyclins, and thromboxanes in mammalian cells. There is now convincing evidence, obtained with a number of structurally distinct inhibitors, that selective COX-2 inhibitors possess anti-inflammatory effects with an improved gastrointestinal tolerability compared with conventional nonsteroidal anti-inflammatory drugs (NSAIDs) affecting both COX-1 and COX-2. As more selective COX-2 inhibitors are being developed, assays with a high degree of sensitivity to inhibition are needed to compare the relative effects of compounds on COX-1 activity. In the present report, we describe a sensitive assay for the inhibition of human COX-1 based on the production of prostaglandin E2 by microsomes from U937 cells incubated with a subsaturating concentration of arachidonic acid. More than 45 NSAIDs and selective COX-2 inhibitors were tested in this assay. IC50 values ranged from 1 nM for flunixin and flurbiprofen to about 200-500 microM for salicylate and acetaminophen. Potent and nonselective NSAIDs such as sulindac sulfide, diclofenac, and indomethacin showed IC50 values of < 20 nM. Among the compounds that have been reported to show selectivity for COX-2, the rank order of potency against COX-1 was DuP 697 > SC-58451 > celecoxib > nimesulide-meloxicam-piroxicam-NS-398-RS-57067 > SC-57666 > SC-58125 > flosulide > etodolac > L-745,337 > DFU-T-614, with IC50 values ranging from 7 nM to 17 microM. A good correlation was obtained between the IC50 values for the inhibition of microsomal COX-1 and both the inhibition of TXB2 production by Ca2+ ionophore challenged platelets and the inhibition of prostaglandin E2 production by CHO cells stably expressing human COX-1. However, the microsomal assay was more sensitive to inhibition than cell-based assays and allowed the detection of inhibitory effects on COX-1 for all NSAIDs and selective COX-2 inhibitors examined with discrimination of their potency under conditions of limited availability of arachidonic acid. PMID- 9365819 TI - Activation of the hepatic glycine cleavage enzyme system by glucagon and glucagon related peptides. AB - The hepatic glycine cleavage system (GCS) is the principal route for the catabolism of glycine in mammals. Flux through the glycine cleavage system in isolated rat hepatocytes is stimulated about 100% at 100 nM glucagon, with half maximal stimulation at 4.3 +/- 1.3 nM. Preincubation of the hepatocytes with the glucagon antagonist des-His1-[Glu9]glucagon amide at 10 microM resulted in inhibition of the glucagon-stimulated GCS by approximately 40%, while the antagonist des-His1-[Nle9,Ala11,Ala16]glucagon amide at 10 microM inhibited the glucagon-stimulated GCS by 80%. Oxyntomodulin and glicentin, glucagon-related peptides, were found to stimulate GCS. Oxyntomodulin, 1 microM, and glicentin, 100 nM, stimulated GCS by 100 and 60%, respectively. Glucagon-like peptide 1 (7 36) amide and glucagon (19-29) (10(-10)-10(-7) M) were without effect. Des-His1 [Glu9]glucagon amide at 10 microM inhibited the oxyntomodulin and glicentin stimulated flux through GCS by about 40%. Thus oxyntomodulin and glicentin can activate the GCS in hepatocytes via interaction with the glucagon receptor but with low affinity. PMID- 9365820 TI - Dose-dependent cardiovascular, renal, and endocrine effects of furosemide in conscious lambs. AB - In recent experiments in conscious lambs, we showed that in addition to its well known natriuretic and diuretic effects, i.v. injection of 2 mg/kg of furosemide resulted in a sustained increase in heart rate and an age-dependent increase in plasma renin activity. To determine whether these responses were dose dependent, we measured various parameters of cardiovascular, renal, and endocrine function in six chronically instrumented lambs. Three of seven doses of furosemide were tested at 48-h intervals; the range of doses was 0 to 7.5 mg/kg. A dose-dependent transient pressor response occurred within 20 min of furosemide administration; the duration of this response increased with increasing doses. Heart rate increased 40 min after doses of furosemide > or = 0.25 mg/kg; this response was not dose dependent. Renin increased following all doses; the peak and the duration of the renin response were dose dependent. These data provide new information on the dose-dependent cardiovascular, renal, and endocrine responses to furosemide in conscious newborn lambs. PMID- 9365821 TI - Isoniazid-induced hepatic necrosis and steatosis in rabbits: absence of effect of gender. AB - Isoniazid, a highly effective drug for the chemoprophylaxis and treatment of tuberculosis, is associated with severe hepatotoxicity in 1-2% of individuals. In a rabbit model of isoniazid-induced hepatotoxicity, we have measured hepatic necrosis (quantitated by elevation of plasma argininosuccinic acid lyase (ASAL) activity), hepatic steatosis (quantitated by elevation of hepatic triglyceride content), and elevation in plasma triglyceride concentration in 15 rabbits. Eight of 15 rabbits were male, and 14 of 15 were rapid acetylators of sulfamethazine. Administration of isoniazid to rabbits resulted in a 27-fold increase in plasma ASAL activities, a 7.5-fold increase in hepatic triglyceride content, and a 13 fold increase in plasma triglyceride levels. This study demonstrated no effect of gender on these three pathological changes that occur in this model of isoniazid induced hepatotoxicity in rabbits. PMID- 9365822 TI - In situ lipolysis measured by in vivo microdialysis during acute cold exposure. AB - The lipolytic responsiveness of interscapular white adipose tissue was measured, in male Sprague-Dawley rats (355 +/- 12 g, n = 7), by microdialysis before, during, and after an acute cold exposure (1 h at 4 degrees C). Microdialysis probes were perfused with standard Krebs-Ringer buffer to determine basal and stimulated rates of lipolysis. The concentration of glycerol in the dialysate was measured and considered as the lipolytic index. During the experiment, energy expenditure was measured by indirect calorimetry. Cold exposure at 4 degrees C doubled energy expenditure. At the same time, it resulted in a 2.7-fold increase in glycerol release. The present study shows that microdialysis is a perfectly adapted tool to investigate in vivo regulation of adipose tissue on awake, unrestrained rats. PMID- 9365823 TI - Characterization of delayed rectifier K+ currents in rabbit coronary artery cells near resting membrane potential. AB - Previous studies have suggested that delayed rectifier K+ (Kdr) channels contribute to the control of membrane potential in vascular smooth muscle. To explore this hypothesis further, we investigated the characteristics of Kdr channels in the negative voltage range in the rabbit coronary artery. The Kdr channel blocker 4-aminopyridine (1 mM) contracted intact vessels and depolarized them from -52 to -37 mV, suggesting that these channels significantly contribute to the maintenance of resting membrane potential. In contrast, the ATP-sensitive K+ channel blocker glybenclamide (3 microM) had little effect on resting tone and did not alter the contraction elicited with 4-aminopyridine. K+ currents in isolated cells were then investigated by using whole-cell patch-clamp techniques. Increasing extracellular K+ concentration ([K+]o) from 5 to 135 mM resulted in the appearance of large inward currents at potentials between -60 and 0 mV. The voltage dependence of conductance for inward K+ currents was steeper and shifted toward more negative potentials when compared with outward K+ currents in 5 mM [K+]o solution. Various blockers of Kdr channels, i.e., 4-aminopyridine (3 mM), phencyclidine (0.1 mM), and intracellular tetraethylammonium (10 mM), nearly abolished currents in high [K+]o solution. In contrast, Ba2+ (0.1 mM) was without effect. These results suggest that the inward currents detected at potentials between -60 and 0 mV in high [K+]o solution are Kdr currents. Our results suggest that Kdr channels physiologically contribute to the control of membrane potential in the rabbit coronary artery. PMID- 9365824 TI - Relationship of red blood cell ion transport alterations and serum lipid abnormalities in Lyon genetically hypertensive rats. AB - Alterations of Na+ and K+ transport in erythrocytes of hypertensive humans or animals are often associated with abnormal lipid metabolism. The aim of the present study was to investigate red blood cell ion transport in Lyon inbred strains selected from Sprague-Dawley rats for different blood pressure levels. Lyon strains are characterized by important metabolic changes, including plasma lipid abnormalities. Serum triglycerides, cholesterol, and uric acid as well as red blood cell Na+ and K+ (Rb+) transport mediated by Na(+)-K+ pump or Na(+)-K+ cotransport and cation leaks were studied in hypertensive (LH), normotensive (LN), and low blood pressure (LL) Lyon rats aged 12 weeks. Increased erythrocyte Na+ content (Nai+) and higher levels of serum triglycerides, cholesterol, and uric acid were demonstrated in LH rats compared with LN animals. Nevertheless, at this age serum triglycerides and erythrocyte Nai+ of LL rats were even higher than those of LH animals. There were no significant differences between Lyon strains in either Na(+)-K+ pump activity or bumetanide-resistant (BR) cation leaks. The activity of bumetanide-sensitive (BS) Na(+)-K+ cotransport mediating inward Na+ movement was highest in LL rats and lowest in LH animals. In Lyon rats, Nai+ was positively related to serum triglycerides, whereas blood pressure correlated positively with BR Na+ leak and negatively with BS net Na+ uptake. A similar association of erythrocyte Nai+ with serum triglycerides was also observed in Prague hereditary hypertriglyceridemic rats (HTG) that were selected from Wistar rats for high plasma triglycerides. The major difference of the two forms of genetic hypertension associated with abnormal lipid metabolism was in BS net Na+ uptake, which was enhanced in HTG but reduced in LH rats. This was probably due to differences in plasma cholesterol, which was elevated in LH but not in HTG animals. Our study in Lyon rats confirmed the positive association of blood pressure with Na+ leak as a characteristic feature of genetic hypertension. PMID- 9365825 TI - A voltage-dependent noradrenaline-sensitive intracellular calcium store in smooth muscle cells of the guinea-pig aorta. AB - In this study we investigated the effects of K+ depolarization on the contractile responses of guinea-pig aortic smooth muscle to noradrenaline (NA) and caffeine (CAF) in Ca(2+)-free Krebs solution (CafKS). NA (1 microM) or CAF (10 mM) in regular CafKS induced a (termed first) phasic contraction, but responses to a second NA or CAF stimulation were significantly reduced, suggesting a depletion of the common intracellular (NA/CAF sensitive) store previously reported by investigators. After the depletion of this store (i) neither 105 mM KCl CafKS nor 10 mM CAF in this high K+ solution induced contraction; (ii) NA-induced contractions were enhanced by KCl, increasing dose dependently with KCl ranging from 25 to 105 mM; (iii) in 105 mM KCl CafKS repetitive NA stimulations elicited enhanced and nondecreasing responses equal to or greater than the first contraction, suggesting an efficient recycling of intracellular Ca2+. In the presence of 10 microM cyclopiazonic acid NA-induced contraction was enhanced, but the response to a subsequent NA stimulation in the absence of cyclopiazonic acid was greatly reduced, implying an inhibition of the Ca2+ recycling function; (iv) 2.0 mM EGTA (ethylene glycol bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid) attenuated the NA-induced contractions in regular and 105 mM KCl CafKS. On the basis of the above results we propose that in the smooth muscle cells of guinea pig aorta, there are two intracellular Ca2+ stores: a NA/CAF-sensitive store and a voltage-dependent NA-sensitive store with effective Ca2+ recycling capability. PMID- 9365826 TI - Reduced sensitivity of fa/fa Zucker rats to adrenomedullin. AB - Rat adrenomedullin is a peptide vasodepressor that may be of importance in the pathogenesis of hypertensive disease. Because of the known link between obesity and hypertension, we hypothesized that decreased responsiveness to adrenomedullin might be seen in an obese rodent model. In this study, the in vivo vasodilator actions of exogenous adrenomedullin were compared in anesthetized lean (n = 7) and obese (fa/fa) Zucker rats (n = 8). Adrenomedullin dose dependently lowered mean arterial pressure in both phenotypes, but the half-maximal dose (ID50) was 2 fold higher in fa/fa rats (1.7 +/- 0.22 vs. 0.83 +/- 0.06 nmol/kg). Moreover, the duration of effect was markedly reduced in the fa/fa rats, to 1-2 min from about 5 min in the lean animals. There was no evidence for an increased rate of degradation of adrenomedullin in the fa/fa rats. Although the rats used in this study were not hypertensive, adrenomedullin had reduced sensitivity and duration of action. The evidence suggests possible defects at the target receptor or altered metabolism of adrenomedullin in obesity. PMID- 9365827 TI - Influence of dopamine receptor and adrenoceptor blockade on the hemoconcentrating and hypotensive actions of atrial natriuretic peptide. AB - Atrial natriuretic peptide (ANP) lowers mean arterial pressure (MAP) and increases hematocrit through reduction in plasma volume caused by a transcapillary shift of plasma fluid and protein toward the interstitium. We examined the consequences of blockade of the dopaminergic and adrenergic systems on the hypotensive and hemoconcentrating responses to ANP. Changes in MAP, hematocrit, and plasma protein concentration (PPC) were measured in anesthetized acutely binephrectomized rats, during infusion of ANP alone (1 microgram.kg-1.min 1 for 45 min) or in the presence of haloperidol (20 micrograms.kg-1.min-1), phentolamine (15 micrograms.kg-1.min-1), or propranolol (10 micrograms.kg-1.min 1). Infusion of ANP reduced MAP by 8.6 +/- 1.3% and increased hematocrit by 9.0 +/- 0.6% (both p < 0.005 vs. vehicle). PPC increased (4.4 +/- 0.6%; p < 0.005 vs. vehicle) significantly less than hematocrit, indicating extravasation of proteins. The ANP-evoked reduction in MAP was not affected in haloperidol- or phentolamine-treated rats (-8.8 +/- 2.3 and -10.5 +/- 2.4%, respectively; both p < 0.005 vs. vehicle) but was abolished in propranolol-treated rats (+3.2 +/- 1.3%; p = ns vs. vehicle). The ANP-induced increase in hematocrit was slightly attenuated in haloperidol-, phentolamine-, and propranolol-treated rats (7.5 +/- 0.7, 7.3 +/- 0.8, and 6.0 +/- 1%, respectively). In addition, the coefficient of reflection, an index of the permeability to proteins, was higher in these three groups (0.41 +/- 0.06, 0.49 +/- 0.08, and 0.57 +/- 0.14, respectively) than in control rats infused with ANP (0.27 +/- 0.03), indicating an attenuation of the ANP-induced extravasation of proteins. Thus, in binephrectomized rats, the hypotensive activity of ANP requires a beta-adrenergic component, whereas its hemoconcentrating action is, at least in part, dependent upon dopaminergic and adrenergic activation. PMID- 9365828 TI - Dendritic cells generated from blood precursors of chronic myelogenous leukemia patients carry the Philadelphia translocation and can induce a CML-specific primary cytotoxic T-cell response. AB - Dendritic cells (DC) are professional antigen-presenting cells specialized in the initiation of primary immune responses. We were interested to know whether mature DC can be grown in vitro from peripheral blood mononuclear cells (PBMC) of patients with chronic myelogenous leukemia (CML), and whether they carry the Philadelphia (Ph) translocation. Using a method recently described, DC were generated from PBMC precursors of 12 patients with CML using GM-CSF, IL-4, and monocyte-conditioned medium. DC exhibited the typical morphology with thin cytoplasmatic processes and expressed high levels of MHC class II, CD86, and CD83 typical for mature DC. After sorting with the monoclonal antibody CD83, a cell population of more than 95% CD83 positive cells was obtained. The presence of the Ph translocation was analyzed in these cells, in PBMC, lymphoblastoid cell lines (LCL), and in phytohemagglutinin (PHA)-induced T blasts from the same patients by fluorescence in situ hybridization (FISH). In contrast to all other cells analyzed, the vast majority of DC (95.9 +/- 0.7%) displayed the Ph translocation, irrespective of disease stage or therapy. PBMC were predominantly positive for the Ph chromosome (67.6 +/- 7.3%), whereas only 11.4 +/- 1% of the B cells and 4.4 +/- 1.1% of the PHA blasts carried the Ph translocation. Using such leukemic DC as antigen-presenting cells, a primary CML-directed cytotoxic immune response in vitro was obtained, as shown by the specific recognition of Ph chromosome positive cells. We conclude that DC can be generated from blood progenitors of CML patients in vitro and exhibit, to a large extent, the Ph translocation. Such DC, which in a preliminary experiment have been able to induce a primary CML directed cytotoxic immune response in vitro, might be ideal candidates for adoptive immunotherapy either by direct transfer of DC for in vivo generation of a T-cell response or by in vitro generation of CML-specific cytotoxic autologous or HLA-matched normal T-cell clones for use in vivo. PMID- 9365829 TI - Differential elimination of 3p and retention of 3q segments in human/mouse microcell hybrids during tumor growth. AB - We have previously found that human chromosome 3 was fragmented in the course of in vivo tumor growth of monochromosomal human/mouse (A9 fibrosarcoma parent) microcell hybrids in SCID mice. Marker analysis of tumor cell lines has identified a regularly eliminated 7 cM segment on 3p21.3 referred to as the common eliminated region (CER). The same region is frequently affected by LOH in a variety of human carcinomas. The present study is a comparative chromosome painting, reverse painting, and PCR marker analysis of microcell hybrids (MCHs) that originally contained an intact chromosome 3 from two alternative donors, during and after four passages in SCID mice. We found regular elimination of 3p in parallel with preferential retention of 3q. In addition to CER on 3p, we can now define a common retained region (CRR) on 3q. It includes eight markers between D3S1282 (3q25-q26) and D3S1265 (3q27-qter) and spans approximately 43 cM. These observations are concordant with the frequent loss of corresponding 3p regions and the frequent retention, with occasional amplification, of 3q in several types of human tumors. PMID- 9365831 TI - Relational mapping of MYCN and DDXI in band 2p24 and analysis of amplicon arrays in double minute chromosomes and homogeneously staining regions by use of free chromatin FISH. AB - MYCN amplification has been observed in diverse neuronal tumors including neuroblastoma, retinoblastoma, and small cell carcinoma of the lung, and has been correlated with a poor prognosis in advanced-stage neuroblastomas. Recent studies have shown a co-amplification of DDXI, a DEAD box gene, and MYCN in retinoblastoma and neuroblastoma. DDXI has been mapped to within a megabase of the MYCN gene in band 2p24. In the present study, the relational map of DDXI and MYCN by fluorescence in situ hybridization (FISH) mapping to metaphase cells and extended free chromatin fibers indicated that DDXI is telomeric to MYCN. Dual color FISH analysis of amplicons within arrays of extended chromatin fibers was performed to examine the physical relationship of MYCN and DDXI within double minute chromosomes (dmins) and homogeneously staining regions (hsrs). No regular reiterated amplicon repeat unit was present in the hsrs, but detailed analysis of the configurations of DDXI and MYCN within each array indicated that multiple rearrangements generated a complex hsr amplicon structure. Similarly, analysis of a cell line bearing dmins showed that a composite amplicon structure involving deletions and/or duplications of MYCN and DDXI is a feature of dmin formation. These data are consistent with a molecular mechanism involving many rearrangements during the evolution of gene amplification, resulting in complex amplicon structures with distinct changes in relative gene copy number and considerable variation in intragenic distances between coamplified genes. PMID- 9365830 TI - Loss of heterozygosity at chromosome segment Xq25-26.1 in advanced human ovarian carcinomas. AB - To determine whether a tumor suppressor gene of importance to epithelial ovarian cancer resides on the X chromosome, we examined loss of heterozygosity (LOH) in 123 epithelial ovarian cancer cases. In 54 such cases, we examined LOH at 26 loci on the human X chromosome. In eight cases, we examined LOH in 14 loci and in 61 cases we examined LOH in 13 loci. Matched DNA samples from tumors and corresponding normal tissues were analyzed by polymerase chain reaction (PCR) amplification of microsatellite markers. Frequent losses were found in epithelial carcinomas at the Xq25-26.l region, including DXS1206 (34.5% loss in informative cases), DXS1047 (27.7%), HPRT (24.1%), and DXS1062 (33.3%). The minimum overlapping region of LOH was approximately 5 megabases (Mb), flanked by DXS1206 (Xq25) and HPRT (Xq26.1). The methylation status of the remaining allele of the androgen receptor gene in the tumors exhibiting LOH at the Xq25-26.1 region suggested that the loss was exclusively in the inactive X chromosome. We next determined whether a significant relationship exists between Xq LOH and other parameters, including histologic grade and/or clinical stage of the tumors and LOH at TP53. The Xq LOH had a significant association with grade 2 to 3 tumors at stages II to IV. Sixteen of 18 cases that showed Xq LOH revealed LOH at the TP53 locus, and 45% of tumors exhibiting LOH at TP53 showed Xq LOH. These results suggest that there may be a tumor suppressor gene or genes which escape inactivation of the X chromosome at Xq25-26.1, and that the loss of the gene(s) at Xq25-26.1 is frequently accompanied by loss of the TP53 or loss of another gene on chromosome 17. These losses may contribute to the progression from a well differentiated to a more poorly differentiated state or to metastatic aggressiveness. PMID- 9365832 TI - Hematologic malignancies with the t(10;11) (p13;q21) have the same molecular event and a variety of morphologic or immunologic phenotypes. AB - Previous studies described the t(10;11)(p13-14;q14-21) as a recurring translocation associated with T-cell acute lymphoblastic leukemia (ALL). This translocation has also been reported in monocytic leukemia or ALL with a very early pre-B phenotype. However, whether these cytogenetically similar translocations involve the same molecular breakpoint is unknown. Using fluorescence in situ hybridization (FISH) with a series of probes on 11q, we mapped the 11q breakpoint of the U937 cell line, which was derived from a patient with diffuse histiocytic lymphoma and was shown by FISH to have the t(10;11)(p13 14;q14-21). Subsequently, we identified a yeast artificial chromosome (YAC) clone, y960g8, that included the breakpoint on 11q. From this YAC, we isolated a PI clone, P91B1, that was split by the 10;11 translocation. We studied four patients with a t(10;11), one of whom had acute monocytic leukemia (AMoL), one had acute lymphoblastic leukemia (ALL), one had lymphoblastic lymphoma (LBL), and one had granulocytic sarcoma, by using FISH with y960g8 and P91B1. Y960g8 and P91B1 were split by the translocation in each patient. We showed that P91B1 included a recently identified gene, CALM (Clathrin Assembly Lymphoid Myeloid leukemia gene), and that AF10 was also rearranged in each patient by FISH when we used y807b3, which contains the AF10 gene. These findings indicate that hematologic malignant diseases with fusion of AF10 and CALM show various morphologic and immunologic phenotypes, suggesting that this fusion occurs in multipotential or very early precursor cells. PMID- 9365833 TI - Suppression of transformed phenotype and tumorigenicity after transfer of chromosome 4 into U251 human glioma cells. AB - The development of primary human brain tumors, particularly glioblastoma multiforme (GBM), has been associated with a number of molecular and chromosomal abnormalities. In this study, a novel tumor suppressor locus was identified and localized after the transfer of a human chromosome 4 into U251 human GBM cells. Hybrid clones containing a transferred neomycin-resistance tagged chromosome 4 revealed an inability to form tumors in nude mice and a greatly decreased efficiency of soft agarose colony formation. As a control, clones containing a transferred chromosome 2 were generated, and these retained the tumorigenic phenotype of the parental U251 cells. The presence of the transferred chromosomes was demonstrated by gain of polymorphic loci and FISH analyses. Several suppressed hybrid clones were shown to contain spontaneously reduced versions of the transferred chromosome 4. A common region of the fragmented chromosome 4 was retained among these clones that included the epidermal growth factor locus at 4q24-26 and several adjacent markers. The identification of a common fragment in the suppressed clones suggests the presence of a tumor suppressor gene or genes in this region, involved in glioma oncogenesis. PMID- 9365834 TI - Detailed deletion mapping of chromosome arm 3p in breast cancers: a 2-cM region on 3p14.3-21.1 and a 5-cM region on 3p24.3-25.1 commonly deleted in tumors. AB - Loss of heterozygosity (LOH) on 3p is frequent in human renal cell carcinomas, lung cancers, and breast cancers. To define the region(s) on 3p that harbor presumptive tumor suppressor gene(s) for breast cancer, we examined 196 primary breast tumors for their patterns of LOH at 22 microsatellite marker loci distributed along this chromosome arm. Allelic loss at one or more loci was observed in 101 (52%) of these tumors. Detailed deletion mapping identified two distinct commonly deleted regions; one was localized to a 2-cM interval flanked by D3S1547 and D3S1295 at 3p14.3-21.1, and the other to a 5-cM interval flanked by D3S1286 and D3S1585 at 3p24.3-25.1. The FHIT gene lies in the vicinity of the proximal commonly deleted region. Attempts to correlate LOH on 3p to clinicopathological parameters detected an association with the absence of the progesterone receptor (P = 0.0096). The results suggest that inactivation of unidentified tumor suppressor genes on 3p plays a role in the mechanism whereby hormone dependency is lost in the course of breast carcinogenesis. PMID- 9365835 TI - Phyllodes tumors of the breast analyzed by comparative genomic hybridization and association of increased 1q copy number with stromal overgrowth and recurrence. AB - Phyllodes tumors are rare neoplasms of the breast. Although they contain both epithelial and stromal components they are considered to be stromally derived lesions. The chromosomal copy number changes were determined in 19 well characterized samples from 18 patients using comparative genomic hybridization. Most chromosomes were involved and generally the gains and losses were similar to those found in breast cancer with the exception that the phyllodes tumors showed no evidence of genomic amplification. The one recurrent sample analyzed had the same imbalances as the original tumor. Frequent changes were gain of 1q (7/18) and loss of 3p (6/18), followed by gain of 7q (4/18) and loss of 6q (4/18) and 3q (3/18). Gain of 1q material was significantly associated with histologically defined stromal overgrowth (P = 0.011). In addition, all the cases with gain of 1q material, without 1p gain, had a clinical history of recurrence. Only one case without 1q gain had a recurrence and this had loss of the X chromosome as the sole abnormality. Increased copy number of 1q material in the phyllodes tumors studied, in one case restricted to 1q24-32, was associated with recurrence (P = 0.00365) and might therefore be considered as an indicator of local aggressiveness requiring more radical treatment. PMID- 9365836 TI - dic(5;17): a recurring abnormality in malignant myeloid disorders associated with mutations of TP53. AB - We have identified three unbalanced translocations involving chromosomes 5 and 17, der(5)t(5;17), der(17)t(5;17), and dic(5;17), in the malignant cells from 17 patients with myeloid neoplasms. Six patients had a primary myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) de novo; ten patients had therapy related MDS and/or AML (t-MDS/t-AML), and one patient had chronic myelogenous leukemia in myeloid blast phase. Two of the six patients with MDS or AML de novo had extensive exposure to industrial solvents, and one patient had Seckel syndrome. The primary diagnoses for the ten patients with t-MDS/t-AML were breast carcinoma and Hodgkin's disease in two patients each, and non-Hodgkin's lymphoma, multiple myeloma, chronic lymphocytic leukemia, ovarian carcinoma, thyroid carcinoma, and rhabdomyosarcoma in one patient each. Four patients had received both prior chemotherapy and radiotherapy, four others received prior chemotherapy only, and the remaining two patients only prior radiotherapy. Fluorescence in situ hybridization of centromere-specific probes for chromosomes 5 and 17 revealed that a dicentric rearrangement was the most common (13/16 patients examined). The genetic consequences of these chromosomal rearrangements are partial monosomy for 5q and 17p. Two of six patients examined had point mutations in TP53, suggesting that loss of function of TP53 in addition to loss of a tumor suppressor gene on 5q may be involved in the pathogenesis of the malignant disease in some of these patients. PMID- 9365837 TI - A case of atypical myelodysplastic syndrome with micromegakaryocytes, normal platelet count, and t(3;12)(q21;p13) with inv(3)(q21q26). AB - A 49-year-old woman patient with atypical myelodysplastic syndrome (MDS) showing a der(3)t(3;12)(q21;p13), and der(12)t(3;12)(q21;p13)inv(3)(q21q26) as an acquired chromosomal abnormality in the bone marrow is described. The chromosomal breakpoints of the presented complex aberration with combination of the inv(3)(q21q26) and t(3;12)(q21;p13) were defined by fluorescence in situ hybridization (FISH) with yeast artificial chromosomes (YACs). The inv(3) is a relatively frequent chromosomal rearrangement in patients with myeloid malignancies and dysmegakaryopoiesis and t(3;12)(q26;p13) has also been reported as a recurrent abnormality in MDS and in blast crisis of chronic myelogenous leukemia (CML). Whereas the t(3;12), inv(3), and t(3;3) are associated with a very poor prognosis, our patient surprisingly had a mild clinical course. PMID- 9365838 TI - BCR/ABL-negative chronic myeloid leukemia with ETV6/ABL fusion. AB - A BCR/ABL-negative chronic myeloid leukemia (CML) with t(12;14) (p12;q11-13) as the sole chromosomal abnormality was investigated by fluorescence in situ hybridization (FISH), which disclosed a cryptic insertion of ETV6 (previously called TEL), located at 12p12, into ABL at chromosome band 9q34. ETV6/ABL fusion was confirmed by RT-PCR, revealing that the first five exons of ETV6 were fused in frame with ABL at exon 2. Wild-type ETV6 was expressed, in accordance with the FISH results showing no deletion of the second ETV6 allele. ETV6/ABL chimeric transcripts have previously been reported in acute leukemias, but never before in CML. The present case suggests that ETV6/ABL positivity may constitute a new genetic subgroup of BCR-negative CML. PMID- 9365839 TI - Mechanisms underlying mismatch repair deficiencies in normal cells. AB - Hereditary nonpolyposis colon cancer (HNPCC) is an autosomal dominantly inherited cancer predisposition which is linked to heterozygous mutations in mismatch repair genes. HNPCC tumour cells, in which the remaining wild-type copy of the mismatch repair gene is inactivated, display instability of microsatellite markers reflecting a defect in mismatch repair. Recently, patients carrying either one of two distinct germline mutations in the MLH1 and PMS2 genes were reported to accumulate somatic mutations of microsatellites in untransformed cells. One of the mechanisms that might account for this phenomenon was a dominant negative effect of the mutant allele. To evaluate this possibility, we examined a different family carrying one of the mutations (deletion of codon 618K in the MLH1 gene) which has been suspected to induce genetic instability in untransformed cells. No mutations in dinucleotide repeat markers were observed in a large number of lymphoblast clones derived from a carrier. Evidence for the deletion of the wild-type allele in two different tumours suggested that the inactivation of both gene copies was required for tumour initiation. These results indicate that the MLH1 618K deletion mutation alone does not necessarily cause marked mismatch repair deficiency in the presence of a wild-type allele. PMID- 9365840 TI - Detection of osteopontin as matrix protein in calcium-containing urinary stones. AB - Osteopontin (OPN) has been identified as a matrix protein of calcium oxalate urinary stones by sequencing c-DNA for urinary stone protein. OPN, a phosphoprotein, is susceptible to thrombin digestion and specifically stainable with Stains-All. We examined the matrix in 4 kinds of urinary stones, calcium oxalate dihydrate, calcium phosphate, magnesium ammonium phosphate and uric acid; for the presence of OPN by staining thrombin-digestion and undigested matrix with Stains-All. Matrix was extracted with a 0.1 M ethylenediamine tetraacetic acid (EDTA) solution. Furthermore, the amino acid sequence was determined for the NH2 terminal 20 amino acid residues. OPN was identified in calcium oxalate dihydrate and calcium phosphate stones, but was absent in magnesium ammonium phosphate and uric acid stones. Our findings suggest that OPN, which binds tightly to hydroxyapatite and is related to bone formation as bone matrix, also participates in the formation of calcium-containing urinary stones. PMID- 9365841 TI - [Analysis of induction of MDR1 gene expression by anticancer chemotherapy in bladder cancer]. AB - Using a reverse transcriptase-polymerase chain reaction (RT-PCR)-based quantitative analysis method, we investigated MDR1 mRNA expression levels in 58 bladder cancer specimens to determine whether MDR1 gene expression was induced or enhanced in bladder cancers during chemotherapy. In bladder cancer specimens which were obtained from patients treated with anticancer drugs, significantly higher expression levels of MDR1 mRNA were observed than in those from patients not treated with any anticancer drugs (p = 0.0134, Mann-Whitney U test). From 14 patients who had bladder cancer, clinical specimens were obtained before and after neoadjuvant intra-arterial chemotherapy. The expression levels of MDR1 mRNA were significantly higher in the post-treatment specimens than in the pre treatment specimens (p = 0.0298, Wilcoxon signed-rank test). Of these 14 patients, 7 patients exhibited increased levels of MDR1 mRNA expression after chemotherapy. In 6 patients, there were no changes in the MDR1 mRNA expression levels before and after chemotherapy. Only one patient exhibited decreased levels of MDR1 mRNA expression after chemotherapy. No significant correlations were observed, between MDR1 mRNA expression levels and effect of the chemotherapy determined microscopically, dosage of anticancer drugs, or patient outcome. In conclusion, this study indicates that MDR1 gene expression in bladder cancers is induced and enhanced during chemotherapy. This overexpression of the MDR1 gene may contribute to resistance to anticancer drugs after repeated chemotherapy. PMID- 9365842 TI - [Comparison of side effects caused by intra-arterial and intravenous infusion of M-VAC (methotrexate, vinblastine, adriamycin and cisplatin) for urothelial cancer]. AB - We retrospectively studied the toxic effects in 14 patients with urothelial cancer who had undergone intra-arterial M-VAC chemotherapy (Group A) and 13 patients who had received intravenous M-VAC chemotherapy (Group V) between February 1991 and August 1995. No statistically significant differences were found in the white blood cell count nadir, liver function, renal function or appetite between the groups. While the platelet count nadir for intra-arterial infusion (14.0 x 10(4)/mm3) was larger than for intravenous infusion (9.0 x 10(4)), the median days to nadir for this count was shorter in the intra-arterial group (9.1 days) than in the intravenous group (13.5). In addition, the difference between the beginning hemoglobin level and the nadir level was larger in the intra-arterial infusion group (2.55 g/dl) than in the intravenous infusion group (1.95 g/dl). Additionally peculiar side effects were noted in the intra arterial infusion group which included local erythema and nerve paralysis. Side effects should be managed for intra-arterial M-VAC as well as for intravenous infusion. PMID- 9365843 TI - [Systematic ultrasound guided transrectal core prostate biopsy based on serum level of prostate-specific antigen]. AB - Between August 1995 and June 1996, a total of eighty Japanese men underwent ultrasound guided systematic biopsy of the prostate. Sixty-six men were clinically suspected of having prostatic cancer by elevated serum PSA (Tandem-R kit) value or digital rectal examination (DRE). Overall, 63 of the 80 (78.8%) men had elevated serum PSA with normal DRE and 30 of the 80 men (37.5%) had prostatic cancer. In patients with PSA values of 0 to 4.0 ng/ml, 4.1 to 10.0 ng/ml and 10.1 ng/ml or more, the positive predictive value of PSA was 33.3%, 23.3% and 66.7%, respectively. In patients with PSA levels of 4.1-10.0 ng/ml, the positive predictive values of digital rectal examination, transrectal ultrasonography and PSA density were 30.0%, 28.0% and 31.8%, and the false-negative rates were 20.0%, 0% and 0%, respectively. Along with the findings of transrectal ultrasonography and PSA density, estimation of PSA value and abnormal findings of digital rectal examination may help minimize the number of biopsies in patients with PSA values of 4.1-10.0 ng/ml. Systematic biopsies were performed without major complications. The biopsy missed the cancer in 4.6%. PMID- 9365844 TI - [Two cases of renal cell carcinoma detected by metastasis to another organ]. AB - Two cases of rare metastases from renal cell carcinoma are reported. The first case was in a 44-year-old man presenting with left exophthalmos. Radiological examination revealed left renal tumor with metastases to paraaortic lymph nodes, left orbit, bone and lungs. Radical nephrectomy was performed. Pathological diagnosis was renal cell carcinoma, pT3aN2M1. The patient died of widespread pulmonary metastasis 5 months postoperatively. The second case was in a 59-year old man with a complaint of tongue tumor. Histopathology of the enucleated tumor was suggestive of metastatic renal cell carcinoma. Computed tomographic scan revealed left renal tumor with regional lymph node metastasis. No other metastasis was found. Radical nephrectomy confirmed the pathological diagnosis of renal cell carcinoma, pT3bN1M1. He has been treated with interferon-alpha and has been free of recurrence for 10 months postoperatively. PMID- 9365845 TI - [A case of unilateral and synchronous occurrence of oncocytoma and renal cell carcinoma]. AB - A 45-year-old female, who had undergone an operation for rectal cancer 4 years previously was admitted to our hospital because of a left renal mass found by follow-up ultrasonography. Ultrasonography revealed two high echoic tumors. Enhanced computerized tomography (CT) showed relatively low density tumors measuring 3.8 x 3.8 cm and 0.8 x 0.8 cm in the upper and lower pole, respectively. Renal angiography demonstrated a spoke-wheel appearance in the upper pole. Left radical nephrectomy was performed. Histopathological diagnosis of the tumor in the upper pole was oncocytoma and that in the lower pole was renal cell carcinoma. PMID- 9365846 TI - [Renal artery embolism treated by selective intra-arterial infusion of tissue plasminogen activator: report of 2 cases]. AB - Two cases of renal artery embolism treated by selective intra-arterial infusion of tissue plasminogen activator (t-PA) are reported. A 74-year-old woman with atrial fibrillation presented with left flank pain of 54-hour duration. Selective renal angiography revealed embolic obstruction of multiple segmental arteries in the left kidney. She was treated by one-shot intra-arterial t-PA infusion (8,000,000 units) and intravenous heparinization (25,000 units/3 days). Although fibrinolysis was successful except for most distal arterial branches, complete recovery of renal function was not obtained. A 66-year-old man presented with complete obstruction of left main renal artery. He had hyperthyroidism and atrial fibrillation. At 75 hours after onset of left flank pain, he was treated by one shot intra-arterial t-PA infusion (18,000,000 units) and intravenous heparinization (4,000 units/24 hours). His renal function was recovered completely. Selective intraarterial t-PA infusion is considered an effective treatment for renal artery embolism. PMID- 9365848 TI - [Ureteral cancer producing carbohydrate antigen 19-9: report of a case]. AB - A case of a CA19-9-producing ureteral cancer is reported. A 58-year-old man presented with gross hematuria. Retrograde pyelography showed an irregular filling defect in the right ureter. The serum CA19-9 level was 932 U/ml (normal < 37). Right total nephroureterectomy was performed. The histological diagnosis was grade 3 transitional cell carcinoma. Immunohistochemical analysis showed CA19-9 to be expressed not only in the cancer cells but also in the normal transitional cell epithelium of the renal pelvis. PMID- 9365847 TI - [A case of recurrent IgA nephropathy following renal transplantation under tacrolimus (FK506)]. AB - We report a case of recurrent IgA nephropathy following renal transplantation under tacrolimus (FK506). A 23-year-old female who had been diagnosed with IgA nephropathy was transplanted from her HLA two-mismatched mother under tacrolimus, prednisolone and azathioprine. Two years after transplantation, suddenly she noticed macroscopic hematuria. At that time, functional renal deterioration (serum creatinine: 2.3 mg/dl) and mild proteinuria were observed. Allograft biopsy disclosed acute cellular rejection. She was administered a bolus injection of methylprednisolone, 15-deoxyspergualin and anti-lymphocyte globulin. However, the response to the treatment was poor. A transplant biopsy revealed focal segmental glomerulosclerosis by PAS staining and granular IgA and C3 deposits on immunofluorescence examination. There was no sign of acute rejection and toxicity by tacrolimus. We diagnosed recurrent IgA nephropathy. At the present time, she has normal urinalysis and renal function is stable (serum creatinine: 1.9 mg/dl). No proteinuria was observed after total dosage of immunosuppressants was increased. Although recurrence of IgA nephropathy in renal allograft is frequent, allograft dysfunction is rare. However, IgA nephropathy has several types with different prognosis. For functional renal deterioration after renal transplantation, we should consider not only an acute rejection or the toxicity of immunosuppressants but also recurrent nephropathy. PMID- 9365849 TI - [Congenital mid-ureteral stricture: report of a case]. AB - A rare case of congenital mid-ureteral stricture is reported. A 17-year-old woman was admitted with sudden onset of right flank pain. Intravenous urography demonstrated bilateral small renal calculi, left hydronephrosis and a stricture of the left ureter at the level of the pelvic brim. The diagnosis was determined as congenital mid-ureteral stricture because the ureter tapered smoothly from 25 mm to 5 mm in diameter at the stenotic site. She was successfully treated by partial ureterectomy with end-to-end anastomosis. Histopathologically, no dysplasia of muscular layer was recognized. PMID- 9365850 TI - [A case of sarcomatoid carcinoma of the bladder: immunohistochemical study on histogenesis of sarcomatoid elements]. AB - An 82-year-old man with microhematuria and class V cells in his urinary cytologic specimen was referred to our clinic. Cystoscopy revealed a solid, broad-based tumor of 1 cm in diameter in the bladder diverticulum. A partial cystectomy was performed. The tumor was composed of transitional cell carcinoma (TCC), sarcomatous spindle cells and the area of transition between TCC and spindle cells. The histopathological diagnosis was sarcomatoid carcinoma. Immunohistochemical examination showed that the spindle cells and the area of transition were positive for keratin, cytokeratin, vimentin and muscle actin. The histopathological and immunohistochemical transitions between the TCC and the spindle cells suggested that the sarcomatous elements originated from the TCC during tumor progression. PMID- 9365851 TI - [A case of xanthogranuloma of the urinary bladder following herniorrhaphy]. AB - We report a case of xanthogranuloma of the bladder following herniorrhaphy. The patient complained of urinary frequency, residual feeling, and presented with a solid mass located on the dome of the bladder. He had undergone previous inguinal herniorrhaphy. Transurethral biopsy revealed an inflammatory change. Partial cystectomy was carried out for en bloc removal of the tumor. The histological diagnosis was xanthogranuloma of the bladder. Postoperatively, the symptoms disappeared. This is the sixth case report of xanthogranuloma of the urinary bladder and the first case following herniorrhaphy in the Japanese literature. PMID- 9365853 TI - [Epididymal sarcoidosis: a case report]. AB - A rare case of epididymal sarcoidosis is reported. A 52-year-old man was admitted with a painless mass in the left scrotum. An operation revealed that a 1-cm mass was located at the epididymal head and well demarcated from the testis and the surrounding tissue. Epididymectomy was performed. Histopathological diagnosis was noncaseating granulomas consistent with sarcoidosis. Systemic examination showed bilateral hilar lymphadenopathy and bilateral peripheral anterior synechiae, but these lesions were diagnosed as inactive. Serum level of angiotensin-converting enzyme was normal. PMID- 9365852 TI - [A case of scrotal cancer with inguinal lymph node metastasis treated by multidisciplinary modalities including chemotherapy with methotrexate, bleomycin and cisplatin]. AB - We report a case of scrotum with inguinal lymph node metastasis which was successfully treated by multidisciplinary modalities including combination chemotherapy and radiotherapy. A 60-year-old man was admitted with ulcerative induration of the scrotum and inguinal lymph node swelling. Biopsy of the scrotal skin showed squamous cell carcinoma. He received 4 courses of combination chemotherapy with methotrexate, bleomycin and cisplatin. The primary lesion disappeared macroscopically and metastatic lymphadenopathy showed 50% reduction in size. Both lesions were further treated with radiotherapy (60 Gy). Because the primary lesion became ulcerative 7 months after irradiation, partial resection of the scrotum was performed. He has been free of recurrence 22 months after chemotherapy. PMID- 9365854 TI - [Is coronary spasmodicity unchangeable?: a study with acetylcholine or ergonovine in patients with ischemic heart disease]. AB - Fluctuations of spasmodicity have been reported in affected vessels in patients with vasospastic angina, but the incidence of spasmodicity induced by pharmacologic agents on both vessels with spasm and vessels without induced spasm has not been investigated. Repeated spasm provocation tests by acetylcholine or ergonovine were performed at 13.1 +/- 9.9 month intervals (3-50 months) in 111 vessels of 50 patients with ischemic heart disease, consisting of 19 old myocardial infarction and 31 angina pectoris, who did not undergo angioplasty or have signs of advancing atherosclerosis. Spasm was defined as present when more than 90 percent stenosis was accompanied by the appearance of usual chest pain or significant electrocardiographic changes. Ninety-six vessels (86.5%), 65 without spasm and 31 with spasm, revealed coincident responses and the remaining 15 vessels contrary reacted. The coincidence rate of spasmodicity in patients at intervals of within 24 months (90.2%) was significantly higher (p < 0.05) than that at intervals of over 24 months apart (70.4%). The spasm coincidence rate was 67.3% in the vessels with provoked spasm by either the first or second tests. Only one (0.9%) out of the 111 vessels showed obvious progressive atherosclerosis during this study. The majority of vessels showed identical spasmodicity within 2 years. In conclusion, coronary spasmodicity might remain unchanged for at least 2 years despite medication with calcium channel blockers and isosorbide dinitrate. PMID- 9365855 TI - [Estimation of myocardial viability and clinical significance of reverse redistribution in resting technetium-99m sestamibi myocardial single photon emission computed tomography in patients with acute myocardial infarction]. AB - The clinical significance of reverse redistribution of technetium-99m sestamibi (MIBI) was investigated in 36 patients with acute myocardial infarction and angiographically confirmed single-vessel disease, but without previous infarction using resting MIBI myocardial single photon emission computed tomography (SPECT) and exercise-reinjection thallium-201 (Tl) myocardial SPECT. MIBI myocardial SPECT was performed 90 min and 300 min after injection of MIBI 370 MBq at rest. Four hours after exercise Tl imaging was completed, reinjection imaging was obtained. Wall motion abnormalities on left ventriculograms were analyzed at the onset of infarction and 1 month later. The severity scores on the MIBI early image, MIBI delayed image and Tl reinjection image were 98 +/- 18, 170 +/- 22 and 90 +/- 18, respectively. The reverse redistribution of MIBI was marked in acute infarction. A significant correlation of severity score was found between the MIBI early image and Tl reinjection image (r = 0.89). In 18 patients with significant stenosis of an infarct-related artery, there was a significant correlation between the degree of reverse redistribution and that of Tl redistribution (r = 0.826). A good correlation was found between the severity score on the MIBI early image and wall motion abnormality at 1 month after infarction (r = 0.816). There was a significant correlation between the degree of reverse redistribution and wall motion improvement (r = 0.782). Despite stenosis of the infarct-related artery, the wall motion abnormality was less in 22 patients with marked reverse redistribution (defect score on the MIBI delayed image was double that on the early image) than the other 14 patients. In conclusion, the MIBI early image may reflect myocardial viability and the reverse redistribution of MIBI was observed frequently in patients with acute myocardial infarction. Marked reverse redistribution was observed in patients with preserved left ventricular function. Because of the close correlation of reverse redistribution with Tl redistribution and wall motion improvement, reverse redistribution of MIBI is considered to occur in areas at risk for acute myocardial infarction. PMID- 9365856 TI - [Relationship between iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid washout ratio and oxygen consumption in normal and ischemic myocardium]. AB - The relationship between oxygen consumption and iodine-123-beta-methyl-p iodophenyl-pentadecanoic acid (123I-BMIPP) washout at rest and after exercise was investigated in normal and ischemic myocardium. Sixteen healthy volunteers and 14 patients with ischemic heart disease were examined. After injection of 111MBq of 123I-BMIPP, serial single photon emission computed tomography imaging was performed to evaluate washout ratio after 30 min and 1 hour of rest and after exercise. In the volunteers, the mean washout ratio was 3.3 +/- 3.5% after 1 hour of rest and increased during exercise. The exercise washout ratio showed a better correlation with net pressure rate product (net PRP: cumulative values of PRP during exercise) than with the peak PRP. The exercise washout ratio showed a strong correlation with the net PRP in the range from 180 to 300 x 10(3) mmHg. beat/min and a plateau of 10-15%. In the nine ischemic patients with net PRP > or = 300 x 10(3) mmHg.beat/min, the exercise washout ratio values were significantly elevated in normal segments relative to ischemic segments (10.1 +/- 1.9% vs 4.7 +/- 2.9%, p < 0.001). In the five ischemic patients with net PRP < 300 x 10(3) mmHg.beat/min, washout ratio at rest and after exercise did not differ significantly between normal and ischemic segments. 123I-BMIPP washout ratio increased with increased oxygen consumption during exercise in normal myocardium but not in ischemic myocardium. The patient must exercise before fatty acid metabolism can be compared between normal and ischemic myocardium. PMID- 9365857 TI - Prediction of wall motion improvement after coronary revascularization in patients with postmyocardial infarction: diagnostic value of dobutamine stress echocardiography and myocardial contrast echocardiography. AB - The diagnostic value of dobutamine stress echocardiography, myocardial contrast echocardiography and dipyridamole stress thallium-201 single photon emission computed tomography (SPECT) for predicting recovery of wall motion abnormality after revascularization was evaluated in 13 patients with postmyocardial infarction. Seventeen segments showed severe wall motion abnormalities before revascularization. Nine segments which had relatively good Tl uptake on delayed SPECT images despite severely abnormal wall motion were opacified during myocardial contrast echocardiography, and showed improved wall motion after revascularization. In contrast, three segments which had poor Tl uptake and severely abnormal wall motion were not opacified during myocardial contrast echocardiography, and showed no improvement in wall motion during dobutamine stress echocardiography and after revascularization. The following three findings were assumed to be signs of myocardial viability: 1) good Tl uptake on delayed SPECT images; 2) improved wall motion by dobutamine stress echocardiography; and 3) positive opacification of the myocardium by myocardial contrast echocardiography. Myocardial contrast echocardiography had the highest sensitivity (100%) and negative predictive value (100%). Delayed SPECT images had the highest specificity (100%) and positive predictive value (100%). Dobutamine stress echocardiography had a sensitivity of 83.0%, specificity of 80.0%, positive predictive value of 90.9%, and negative predictive value of 66.7%, respectively. Myocardial contrast echocardiography showed the lowest specificity (60.0%). The techniques of dobutamine stress echocardiography and SPECT, though noninvasive, may underestimate wall motion improvement after revascularization. Further examination by myocardial contrast echocardiography is recommended to assess myocardial viability for determining the indications for coronary revascularization in spite of its invasiveness. PMID- 9365858 TI - [Non-invasive determination of the quantity of pleural effusion and evaluation of the beneficial effect of pleuracentesis in patients with acute exacerbation of chronic congestive heart failure]. AB - A non-invasive method to determine the quantity of pleural effusion and to evaluate the beneficial effect of pleuracentesis in patients with acute exacerbation of chronic congestive heart failure was evaluated. Twenty-three patients with pleural effusion due to acute exacerbation of chronic congestive heart failure were studied. The angle (x) formed by the diaphragm and lung (right side) or pericardium (left side) was measured by ultrasonography in the sitting position using the subscapular approach. Pleuracentesis was then performed in 15 patients, and the quantity of aspirated pleural effusion (y) was measured and compared with the angle x. There was significant relationship between y and x: y = 0.125 x 10(0.017x) (r = 0.77, p < 0.01). The 18 patients with more than 500 ml of estimated one-sided pleural effusion were divided into two groups; the nonpleuracentesis group (n = 8) and the pleuracentesis group (n = 10). The intravenous furosemide dose per increased body weight, and the term of oxygen supply and time to disappearance of edema were compared between the two groups. Intravenous furosemide dose was lower (p < 0.05) and the term of oxygen supply was shorter in the pleuracentesis group than in the nonpleuracentesis group (p < 0.05), whereas time to disappearance of edema was not significantly different. This non-invasive method can estimate the quantity of pleural effusion, and pleuracentesis had beneficial effect on patients with pleural effusion of greater than 500 ml (the angle x > 35 degrees ) in patients with acute exacerbation of chronic congestive heart failure. PMID- 9365859 TI - [Native aortic valve thrombus revealed by routine echocardiography: a case report]. AB - A 75-year-old man presented with palpitations due to atrial flutter. Transthoracic echocardiography revealed a mobile aortic valve mass (17 mm in diameter) attached to the non-coronary cusp of the aortic valve. There was no evidence of hypercoagulative state. Computed tomography showed old cerebral infarction in the territory supplied by the right middle cerebral artery. The mass was surgically resected. The aortic valve was preserved because there were no organic changes in the valve. Histological examination demonstrated an organized thrombus. Only three cases of thrombus attached to the normal native aortic valve have been reported. Native aortic valve thrombus may be important in the differential diagnosis of aortic valve mass. PMID- 9365860 TI - [A 75-year-old man with jaundice and severe leg edema. Idiopathic restrictive cardiomyopathy with severe right-sided heart failure]. PMID- 9365861 TI - Fingerstick blood samples in platelet donor screening: reliability and impact on predict yield programs. AB - Although widely used, the reliability of fingerstick platelet counts for determining donor eligibility and for use with plateletpheresis predict yield programs has not been established. We compared platelet counts obtained from fingerstick vs. venous samples in several aspects of apheresis platelet collection. Analysis of 25 paired fingerstick and venous predonation samples demonstrated a poor correlation between platelet counts (r2 = .43), with fingerstick counts having a 20% lower mean value (P < .05). The effect of using fingerstick vs. venous predonation platelet counts with apheresis instrument predict yield calculations to obtain target yields was determined. Mean yields collected using fingerstick/predict yield were 12% (Fenwal CS3000 PLUS) and 15% (Haemonetics MCS+) higher than venous/predict yield units (P < .05). The coefficients of variation (CV) of fingerstick/predict yield and venous/predict yield collections were comparable (15% vs. 14% [CS3000] and 23% vs. 21% [MCS+], respectively), indicating that possible differences in accuracy between fingerstick and venous platelet counts had little effect on the variability of predict yield collections. A retrospective analysis of the CV of 100 fingerstick/predict yield units vs. 100 units collected by processing standard volumes showed no difference: 22% vs. 20% (F = 0.99, CS3000), and 22% vs. 24% (F = 0.89, MCS+), respectively. We conclude that fingerstick platelet counts are systematically lower and correlate poorly with venous counts, though their use seldom results in false disqualification of donors. We also conclude that fingerstick count/predict yield collections do not produce more consistent yields of platelets than standard volume collections. PMID- 9365862 TI - Cholesterol biosynthesis in normocholesterolemic patients after cholesterol removal by plasmapheresis. AB - Plasmapheresis and low-density lipoprotein (LDL)-apheresis are recognized procedures for the treatment of hyperlipidemia resistant to diet and lipid lowering drugs and provide information on cholesterol synthesis in hypercholesterolemic patients. However, cholesterol synthesis after acute cholesterol removal from plasma has never been investigated in normocholesterolemic patients. In this study, cholesterol synthesis was evaluated in three normocholesterolemic patients by determination of plasma lathosterol, lathosterol-to-cholesterol ratio, and plasma mevalonic acid. In a short-term kinetic study, samples were collected before and after plasmapheresis and every 6 hours during 24 hours. In the second part of the study, cholesterol synthesis was evaluated daily for 3 days. In normocholesterolemic patients, cholesterol returns to basal levels in 3 days. However, cholesterol removal did not result in a significant increase in lathosterol-to-cholesterol ratio or in plasma mevalonic acid, despite a slight increase in lathosterol. In contrast, when repeated plasma exchanges induced a dramatic hypocholesterolemia (< 1 mmol/liter), an acute but transient stimulation of cholesterol synthesis was observed (lathosterol/cholesterol ratio and MVA, respectively, increase from 8.2 to 22.3 and from 28 nmol/liter to 98 nmol/liter). This study shows that cholesterol synthesis is not stimulated by plasmapheresis in normocholesterolemic patients but is enhanced in dramatic hypocholesterolemic patients (< 1 mmol/liter). PMID- 9365863 TI - Characteristics of 73 patients, 1984-1993, treated by plasma exchange for Guillain-Barre syndrome. AB - Acute Guillain-Barre syndrome (GBS) is a demyelinating polyneuropathy which responds readily to plasma exchange (PEX). According to the North American Acute GBS PEX study there is a 50% or more reduction in the recovery time if PEX is initiated early in the course of the disease. Demyelinating antibodies are usually IgM. IgA antibodies require prolonged PEX. Patients with predominant IgG antibodies have chronic inflammatory demyelinating polyneuropathy (CIDP), which requires an even longer course of PEX, over weeks to months or years. We reviewed records of 73 patients with the initial diagnosis of GBS treated with PEX. Among these patients, 55 had classic GBS, three had the Miller-Fisher variant, two had CIDP, and 13 had demyelinating-like polyneuropathies associated with other conditions including malignancy, vaccine-related myelitis, steroid-induced myopathy, polymyositis, botulism, gram-negative sepsis, Sjogren's, and AIDS. Hughes grading system was used. Patients were graded 3 to 5, with grade 3 patients being unable to walk 5 m without support, grade 4 patients being bed or chair bound, and grade 5 patients being ventilator dependent. Of 60 unassociated (GBS) demyelinating cases receiving a mean of 6.5 PEX procedures, 13 (21%) were intubated early in the treatment, with four (6%) remaining ventilator dependent post-PEX. Of 51 non-intubated patients, 15 became ambulatory post-PEX. Patients with the Miller-Fisher variant showed improvement within 6 hours of PEX initiation. We did not investigate correlation of GBS with infection; however, we did observe a rise in CMV titer among 15% of the 58 patients with acute GBS. Considering our results we believe that intensive PEX on a daily basis for a few days is necessary for severely affected individuals. We advise five to nine procedures at consultation unless early, rapid recovery occurs. PMID- 9365864 TI - Loss of red cells from the use of blood warmers during apheresis procedures. AB - In-line blood warmers increase the extracorporeal volume of apheresis procedures. A saline rinse of the blood warmer may be employed to minimize the loss of red blood cells (RBCs) from this extra volume. We measured the amount of RBCs remaining in three different brands of blood warmers at the end of a COBE Spectra rinseback to determine the clinical significance of blood warmer saline rinses. The volume of RBCs removed by a warmer rinse ranged from 15 to 24 ml per procedure and was statistically different among the three brands of warmers. The COBE warmer contained significantly less RBCs than either the Fenwal or Pharmaseal warmers. Patient hematocrit was not highly correlated with the residual RBC volume (r = 0.30). We estimate that 15-20 procedures are required before the equivalent of one unit of packed RBCs is lost to blood warmers. We conclude that the blood warmer saline rinse may be safely omitted for most patients. PMID- 9365865 TI - Collection of platelets and peripheral progenitor cells with the fresenius AS.TEC 204 blood cell separator. AB - The aim of the present study was to clinically evaluate the blood cell separator AS.TEC 204. One hundred fifteen platelet collections were carried out with the dual or single needle procedure. Platelet yield was 3.21 +/- 0.80 x 10(11) (mean +/- standard deviation) and 59.1% of the collections showed platelet counts > or = 3.0 x 10(11). Leukocyte contamination was 1.77 +/- 2.81 x 10(6) and 89.0% of the platelet concentrates had a white blood cell content < 5 x 10(6). Using a dual needle technique with an alternating interface adjustment, all of the products were contaminated with less than 1 x 10(6) leukocytes. Furthermore, 23 peripheral progenitor cell collections were performed in 12 patients and three allogeneic donors. Median numbers of harvested CD 34 antigen expressing cells/kg body weight were 0.78 (range 0-4.7) and 3.67 x 10(6) (range 2.2-5.23), respectively. We conclude that platelet and progenitor cell collections can be carried out with efficient results. The collections were well tolerated by the donors. PMID- 9365866 TI - Rationale, objectives, and interpretation of randomized controlled trials. AB - A randomized controlled trial (RCT) is the most definitive tool for evaluation of the effectiveness of an intervention and can establish a cause-and-effect relationship between an intervention and an improved disease outcome. However, the undertaking of an RCT does not guarantee valid results, and the findings of RCTs of the same intervention are often discrepant. While many reported trials are of high quality, a significant number have deficiencies in design, conduct, analysis, or interpretation of results. Medical practitioners must become familiar with the methodology of RCTs in order to assess the validity of the reported findings and the relevance of the results to their own patients. Trialists must report sufficient information about the methods used so that readers can judge for themselves if the trial worked as planned. PMID- 9365867 TI - Prospects for intravascular gene therapy. AB - The goal of this review is to provide an overview of gene delivery systems and candidate genes currently being evaluated for genetic strategies in vascular gene therapy. We will discuss treatment strategies that have been shown by in vivo model systems to be efficacious in promoting neovascularization of ischemic tissue or limiting post-interventional restenosis by inhibiting smooth muscle cell proliferation and/or encouraging re-endothelialization. PMID- 9365868 TI - Alternatives to albumin: starch replacement for plasma exchange. AB - Today, albumin, or a combination of saline and albumin, is used and widely accepted as a replacement for routine plasma exchange. However, decreased availability (due to market recalls secondary to Creutzfeld-Jacob or bacterial contamination risk) rising costs, recognition of drug interactions with albumin (i.e., ACE inhibitors) and a fear of disease transmission have led several groups to reconsider the use of colloid starches as partial or full replacement for plasma during plasma exchange. There are two hydroxyethyl starches: hetastarch (Hespan and Pentaspan) currently licensed for human use in the United States. While both are approved for granulocyte collection only Hespan is approved as a plasma volume expander. Anecdotal experience and limited reports in the literature with the use of starches as a replacement for plasma exchange suggest that such starch products are a reasonable replacement for albumin as an initial wash-out fluid or in combination with either albumin or saline. Kinetic modeling of the wash-out of starch used as a replacement fluid demonstrate that relatively little residual starch remains compared to the total amount infused. Hydroxyethyl starches are biochemically similar to glycogen, which likely explains the lack of immunogenicity and lack of adverse reactions. Substantial cost savings are associated with the substitution of starch for albumin. It is concluded that HES is well-tolerated and cost-effective as full or partial volume replacement with plasma exchange. It is anticipated that the use of HES will emerge as a standard of care in apheresis. PMID- 9365869 TI - Photopheresis--a possible treatment of multiple sclerosis?: report of two cases. PMID- 9365870 TI - Use of losartan in FH patients during treatment with DSC-LDL apheresis. PMID- 9365871 TI - Decreased cortical bone thickness in spontaneously non-insulin-dependent diabetic GK rats. AB - We studied the occurrence of osteopenia, as reflected by decreased cortical bone thickness, in a nonobese animal model of hereditary non-insulin-dependent diabetes with long duration, i.e., 8-month-old Goto-Kakizaki (GK) rats. In addition, motor nerve-conduction velocity was measured in the GK rats. Age- and weight-matched Wistar rats served as controls. The GK rats displayed marked glucose intolerance, as compared to control rats, in an intraperitoneal glucose tolerance test. Decreased cortical bone thickness by approximately 15%, was evident in X-ray analysis of metatarsal bones (p < 0.001) and humerus (p < 0.05) of the GK rats. Motor nerve-conduction velocity, measured in the sciatic nerve, was also decreased (by 10%) in the GK as compared with the age-matched control rats (p < 0.05). In conclusion, reduction of cortical bone thickness is present in 8-month-old GK rats, which simultaneously demonstrate signs of peripheral neuropathy. Thus, the GK rat appears to be a model of NIDDM suitable for studies of diabetic bone disease in the absence of obesity. PMID- 9365872 TI - Ethnicity and prevalence of scleroderma-like syndrome: a study of Arab and Jewish Israeli insulin-dependent diabetic children. AB - Scleroderma-like syndrome (SLS) may represent the earliest apparent diabetes complication in insulin-dependent diabetic (IDDM) patients. To evaluate the frequency of SLS and its association with other diabetes-related pathology in our diabetic population, we studied 153 (127 Jewish and 26 Arab) IDDM patients and 45 healthy age- and gender-matched controls (25 Jewish, 20 Arab). The mean age and diabetes duration of the patients were 14.09 +/- 5.1 years and 51 +/- 45 months, respectively. While no diabetes-related pathology was found in the controls, SLS was detected in 47% of all patients (skin, 31.4%; arthropathy, 37.9%; both, 22%), and nephropathy, neuropathy, and retinopathy were present in 10.5%, 5.2%, and 4.6%, respectively. Independent of age, SLS directly correlated with diabetes duration (p < 0.01) and with the presence of either nephropathy or neuropathy (p < 0.009 and p < 0.005, respectively). One or more features of systemic diabetic involvement were present in 22% of patients with SLS, compared to only 7.2% in patients without SLS (p < 0.009). When patients were analyzed according to ethnicity, the frequency of skin involvement and neuropathy were found to be higher among Arab patients, particularly males (p < 0.002 and p < 0.005, respectively), and detection of one was significantly associated with the presence of the other (p < 0.001). In conclusion, our results suggest that SLS is the most common diabetic complication among Jewish and Arab IDDM patients, and its presence may reflect an inherited tendency to develop other serious diabetic complications. Ethnicity (Arab) by itself, particularly when associated with male gender, seems to accelerate neurological and dermatological diabetic involvement. PMID- 9365873 TI - Pancreatic polypeptide secretion in diabetic patients with delayed gastric emptying and autonomic neuropathy. AB - Measuring postprandial pancreatic polypeptide (PP) plasma concentration is a sensitive method for autonomic nervous system assessment. Delayed gastric emptying (DGE) often does not correlate clearly with cardiac autonomic neuropathy (CAN). This study was conducted to evaluate whether decreased PP secretion (PPS) accompanies DGE and CAN in diabetes. Fourteen long-standing diabetics with DGE assessed by scintigraphy (group A), 14 well-matched diabetics with normal gastric emptying (NGE) (group B), and 12 healthy controls (group C) were the study subjects. CAN and postprandial PPS at 0, 30, and 60 min after test meal ingestion were examined in all the subjects, and the area under curve of PP secretion was calculated. There was no correlation between DGE and CAN (eight diabetics with CAN in A and six in B). Basal PP values were almost the same in all the patients (mean 77.27 +/- 11.0 pg/mL). The area under curve of PP secretion values (PPAUC) after test meal ingestion were significantly higher in B (211.84 +/- 36.13 pg/mL/h; p < 0.0001) and C (233.68 +/- 23.43 pg/mL/h; p < 0.00001) than in A (147.59 +/- 31.77 pg/mL/h). Diabetics with CAN had lower PPS expressed as PPAUC than those without CAN, which was independent of gastric emptying rate (152.31 +/ 37.18 versus 207.12 +/- 39.21 pg/mL/h; p < 0.001). There were no significant differences between test meal-stimulated PPAUC in diabetics without CAN (207.12 +/- 39.21 pg/mL/h) and controls (233.68 +/- 23.43 pg/mL/h), and this was also independent of gastric emptying rate. In patients with both DGE and CAN, the PPS was completely blunt (PPAUC 124.04 +/- 5.71 versus 233.68 +/- 23.43 pg/mL/h in controls; p < 0.001). The PPS in diabetics with CAN and NGE was significantly lower than in controls (PPAUC 190.0 +/- 37.45 versus 233.68 +/- 23.43 pg/mL/h; p < 0.01). In conclusion, the PPS in diabetics with CAN was decreased significantly and independently of DGE. The PP secretion was very low in diabetics with both CAN and DGE. PMID- 9365874 TI - Smoking habits and painful diabetic neuropathy. AB - In order to assess the relationship between chronic painful diabetic neuropathy and current--or lifetime--smoking habits, the smoking history of 49 diabetic patients was investigated and compared with that of 23 diabetic patients without chronic pain (age 51.0 +/- 1.9 years, mean +/- SEM). Current level of nicotine intake was measured using urinary cotinine (a nicotine metabolite), and expressed as cotinine/creatinine ratio (COT/Cr), and lifetime smoking load by pack years (20 cigarettes per day for 1 year equals 1 pack year). Current pain intensity was evaluated using a visual analogue scale (VAS). The presence of chronic painful diabetic neuropathy was based on clinical history and examination. Of those patients with painful neuropathy, 26% were current smokers (age 54.2 +/- 3.2 years, mean +/- SEM), 31% ex-smokers (age 57.0 +/- 2.9 years), and 43% lifelong nonsmokers (age 58.0 +/- 2.9 years). Pain duration and intensity were similar in all three groups. COT/Cr levels were similar in current diabetic smokers with pain [5.0 (0.2-10.6) micrograms/mg] and the diabetic control group of smokers without pain [6.8 (1.8-13.3) micrograms/mg, NS]. There was no relationship between VAS and either COT/Cr levels or pack years in current smokers, or between duration of pain and pack years in diabetic current or ex-smokers. In conclusion, we found no relationship between current or previous levels of smoking and severity or duration of chronic painful diabetic neuropathy. PMID- 9365875 TI - Effects of advanced glycation endproducts on the generation of macrophage mediated oxidized low-density lipoprotein. AB - Macrophages have a receptor that recognizes advanced glycation endproducts (AGE). In this study, we evaluated the effect of AGEs on the generation of macrophage mediated oxidized low-density lipoprotein (LDL) by measuring the electrophoretic mobilities and lipid hydroperoxide (LHPO) levels of LDL. In the absence of the macrophage monolayer, the differences of the electrophoretic mobilities or LHPO levels of native (n) LDL did not differ significantly between control (c) bovine serum albumin (BSA) and those with AGE-BSA. In the presence of the macrophage monolayer, however, the difference was significant with higher levels after the incubation with AGE-BSA than with c-BSA. In the case of cLDL and glycated (g) LDL, the electrophoretic mobilities and LHPO levels of LDL after 20 h incubation with AGE-BSA in the presence of the macrophage monolayer were significantly higher than those with c-BSA. There were no significant differences, however between the electrophoretic mobilities and LHPO levels of cLDL and of gLDL. These results suggest that AGEs stimulate the generation of macrophage-mediated oxidized LDL, but do not directly stimulate the oxidative modification of gLDL. PMID- 9365876 TI - Prevalence and epidemiology of micro- and macroalbuminuria in Ethiopian diabetic patients. AB - A cross-sectional study was conducted on the prevalence and epidemiology of micro and macroalbuminuria in diabetic outpatients in Gondar, Ethiopia. Microalbuminuria was defined as a mean urinary albumin concentration of 30-299mg L-1 in morning urine of three consecutive visits. The frequency of micro- and macroalbuminuria was 32% and 15% in IDDM patients and 37% and 20% in NIDDM patients, respectively. When only patients with a duration of more than 5 years were considered, micro- and macroalbuminuria were prevalent in 33% and 23% of IDDM, and 36% and 31% of NIDDM patients, respectively. In multiple regression analysis, urinary albumin levels (log) were significantly associated with systolic blood pressure and duration in IDDM patients even when proteinuric patients were excluded from the analysis. In NIDDM patients duration and diastolic blood pressure were significant predictors of urinary albumin concentrations. In order to delay chronic complications, screening for microalbuminuria by stick-testing in urine should be introduced into routine laboratory practice in developing countries. PMID- 9365877 TI - Diabetic cystopathy presenting as primary acute urinary retention in a previously undiagnosed young male diabetic patient. AB - Lower genito-urinary problems are part of the polyneuropathy of diabetes. Cystopathy affects 40%-85% of diabetic patients, although less than half are symptomatic. We report on a 42-year-old patient who was not known to be diabetic, and who presented to the urologists with primary acute urinary retention. His underlaying disease was detected by a test for random blood glucose. More common causes were excluded with careful clinical and radiological examinations. He was managed with insulin and self-catheterization. Diabetes should be considered as a differential diagnosis in relatively young men who present with unexplained acute urinary retention. PMID- 9365879 TI - Options for diabetic patients with chronic heel ulcers. AB - The presence of a heel ulcer in the diabetic patient is usually due to neuropathy, vasculopathy, or both. Diagnostic testing including noninvasive assessment by nerve conduction velocity and Doppler pressure measurements can provide the basis for subsequent treatment. The diagnosis of osteomyelitis is assisted by plain radiographs, isotope definition, and/or magnetic resonance imaging (MRI). The loss of the calcaneus may mean loss of the functioning foot. Reconstructive arterial surgery for heel lesions in the diabetic patient has limited success. Prevention and local wound care, along with patient education, will result in limb salvage and the prevention of disability. PMID- 9365878 TI - Predictors of renal and cardiovascular mortality in patients with non-insulin dependent diabetes: a brief overview of microalbuminuria and insulin resistance. AB - Both microalbuminuria and insulin resistance are present at some stage in the natural history of non-insulin-dependent diabetes mellitus (NIDDM). Microalbuminuria predicts both progression to endstage renal disease and an increase in cardiovascular mortality compared to diabetic patients without microalbuminuria. Conversely, microalbuminuria is not a strong predictor of either renal or cardiovascular mortality in hypertensive nondiabetic subjects. This difference in risk may relate to the presence of glycated albumin in patients with diabetes. Glycation of albumin occurs because of persistent hyperglycemia. Glycated albumin is directly toxic to both renal and vascular tissue through stimulation of reactive oxygen species by both renal and immune protective cells. Blunting the rise in microalbuminuria with either aggressive blood glucose control or angiotensin-converting enzyme (ACE) inhibition, early in the course of the disease, markedly reduces renal mortality. In contrast to microalbuminuria, which is a reflection of renal injury, insulin resistance is a genetically determined problem that directly relates to peripheral glucose utilization. In most cases, insulin resistance is phenotypically expressed as diabetes as a result of environmental factors such as obesity. Insulin resistance is associated with an increased risk for development of both hypertension and NIDDM as well as atherosclerosis. Diabetic or hypertensive subjects with insulin resistance have an increased risk of cardiovascular but not renal mortality. Sustained weight loss is the best way to reduce insulin resistance and arterial pressure. Additionally, alpha blockers, more than other antihypertensive agents reduce insulin resistance. This class of drugs, however, has not been shown to reduce either microalbuminuria or overall cardio-renal mortality. PMID- 9365880 TI - Human papillomavirus type 11 neutralization in the athymic mouse xenograft system: correlation with virus-like particle IgG concentration. AB - Neutralization of virus is likely to be necessary for development of an effective prophylactic vaccine against genital human papillomavirus (HPV) infection. Two New Zealand white rabbits were immunized with purified HPV type 11 (HPV 11) virions in Freund's adjuvant. An enzyme linked immunoassay (ELISA) was used to determine the quantity of IgG which recognized the HPV 11 major capsid protein (L1 protein) virus-like particles (VLPs) in the two anti-HPV 11 sera (serum A and serum B). The concentration of HPV 11 L1 VLP-specific IgG in the A and B sera were determined to be 37 and 90 micrograms per ml, respectively. The A and B sera were used in neutralization experiments in the athymic mouse xenograft system with known quantities of purified HPV 11 virions. The concentration of HPV 11 L1 VLP-specific IgG required to neutralize HPV 11 was determined for each antiserum. This concentration of IgG was approximately 700 to 900 ng per ml. This study demonstrates a positive correlation between the level of HPV 11 L1 VLP-specific IgG in animals immunized with HPV 11 virions and neutralization of HPV 11 in the athymic mouse model. Further studies are needed 1) to determine if sera or genital secretions from other species are neutralizing in the athymic mouse xenograft system, and 2) to determine if the VLP ELISA can be used as a reliable substitute for more cumbersome neutralization assays. PMID- 9365881 TI - Monitoring for cytomegalovirus infection in organ transplant recipients: analysis of pp65 antigen, DNA and late mRNA in peripheral blood leukocytes. AB - The use of sensitive and specific methods for rapid and reliable diagnosis is required due to the considerable impact of human cytomegalovirus (HCMV) in organ transplant recipients. For this purpose the demonstration of the presence of viral antigens in peripheral blood leukocytes (PMNLs) and of viral nucleic acids in the same cells or in sera would seem to be of valid support. The present study was designed to test pp65 antigen, HCMV DNA and HCMV late mRNA in order to provide clinical information for the management of the infection. Fifty solid organ recipients were monitored for six months after transplant. The data obtained from the various tests were analysed from the first evidence of HCMV infection revealed by positive antigenaemia and/or DNA-polymerase chain reaction (PCR). In 3 asymptomatic and in 7 symptomatic patients, PCR became positive 1-2 weeks before antigenaemia but PCR did not discriminate the clinical evolution of HCMV infection. The antigenaemia test well correlated to the development of viral infection being positive in all symptomatics and in 31, 2% of asymptomatics. The antigenic load > 100/2 x 10(5) positive cells was always associated with clinical signs of illness. The detection of late mRNA was more indicative of the virus replicative status in the follow-up of patients treated with ganciclovir. In some cases there was evidence, prior to the other two tests, the block of viral replication due to the antiviral therapy and in others the onset of HCMV infection relapse. PMID- 9365882 TI - Enterovirus heart disease of adults: a persistent, limited organ infection in the presence of neutralizing antibodies. AB - Detection of enterovirus RNA in endomyocardial biopsies (EMB) by reverse transcription/polymerase chain reaction (RT-PCR) is currently the preferred diagnostic procedure in suspected enterovirus heart disease (EHD), which can present clinically as myocarditis, dilated cardiomyopathy (DCM), and arrhythmogenic right ventricular cardiomyopathy (ARVC). EMB and peripheral blood mononuclear cells (PBMC) of 44 patients with suspected EHD were examined by nested RT-PCR to investigate whether the myocardial enterovirus infection is limited to the heart or is generalized. Enterovirus RNA was detected in EMB, but not in PBMC, of 8 patients (3 of these suffered from ARVC), whereas EMB of 16 controls and PBMC of 45 controls were negative. In addition, enterovirus RNA was demonstrated in PBMC, but not in EMB, of a single patient with suspected EHD. A high sequence homology of the amplicons to coxsackievirus B3 was demonstrated in 7 patients, and to coxsackievirus B2 in two patients. In order to evaluate whether the myocardial enterovirus infection was acute or persistent, neutralization and complement fixation tests were performed for antibodies against the serotypes indicated by the nucleic acid sequences. Neutralizing antibodies were detected in the sera of all 9 patients, but complement fixing antibodies were demonstrated only in one EHD patient and in the patient positive for enterovirus RNA in PBMC. In conclusion, the molecular and serological data demonstrate that CVB3 predominates as cardiotropic enterovirus, and that the enterovirus replication is limited to the heart in EHD. Serological results support the hypothesis of myocardial enterovirus RNA persistence in spite of neutralizing antibodies. PMID- 9365883 TI - Identification and typing of molluscum contagiosum virus in clinical specimens by polymerase chain reaction. AB - A polymerase chain reaction (PCR) which enables the detection of molluscum contagiosum virus (MCV) genomes in either fresh or formalin-fixed clinical specimens is described. The primers used were designed to amplify a 167 bp region of the 3.8 kbp HindIII fragment K of the MCV 1 genome. The ability of this PCR to detect three common MCV types (1, 1v and 2) in clinical specimens was confirmed using frozen extracts from 75 molluscum lesions, and digests of single sections of 11 formalin-fixed, paraffin-embedded lesions; all of which had been previously typed by Southern hybridisation. In addition, 2 specimens previously negative by hybridisation were shown to be positive for MCV DNA by PCR. Confirmation of the identity of the PCR products and distinction between the two major MCV types (MCV 1/1v versus MCV 2) was achieved by comparison of the results of cleavage with the restriction endonucleases Hhal and Sacl. Sequencing of the PCR products revealed complete homology between MCV 1 and 1v, but minor nucleotide variations between MCV 1/1v and MCV 2 were identified. As well as providing a highly sensitive means of diagnosis, the technique may also prove useful for investigations into the pathogenesis, epidemiology and natural history of molluscum contagiosum infection. PMID- 9365884 TI - Molecular detection and characterization of yellow fever virus in blood and liver specimens of a non-vaccinated fatal human case. AB - A yellow fever virus of a South American genotype was identified in the liver and blood samples of a non-vaccinated European patient after his return from Brazil. ELISA tests were negative for IgG and positive for IgM against yellow fever. Yellow fever proteins in the formalin-fixed and paraffin-embedded liver biopsy were detected by immunohistochemical procedures. Viral RNA extracted from the liver tissue was also detected using an RT-semi-nested PCR procedure and molecular hybridization. Alignment of the sequence obtained from a gene fragment amplified by RT-semi-nested PCR directly from a blood sample with those of African and South American yellow fever virus strains identified a Brazilian topotype as being responsible for the disease. RT-semi-nested PCR may be used advantageously for clinical specimens for rapid and specific diagnosis, and with archival biopsy material for retrospective studies. PMID- 9365885 TI - Frequencies of GB virus C/hepatitis G virus genomes and of specific antibodies in German risk and non-risk populations. AB - The prevalence of the new flavivirus GB virus C/hepatitis virus G (GBV-C/HGV) in different German populations was investigated by detection of viral genomes and anti-E2 antibodies. While blood donors had an overall prevalence of 10.4% there were increased rates for hemophiliacs (54.7%), hemodialysis patients (30.2%), male homosexuals (30.2%) and intravenous drug users (74.4). Most GBV-C/HGV positive samples were either viral genome positive or antibody positive, exclusively. Samples with the rare constellation "positive for both GBV-C/HGV genome and specific antibody" originated in almost all cases from patients who were additionally infected with HIV or HCV. Probable transmission of GBV-C/HGV by PCR-positive blood transfusions was observed in 5 of 6 cases approximately six months after transfusion. PMID- 9365886 TI - High prevalence of GBV-C hepatitis G virus infection in a rural South African population. AB - A novel virus, GBV-C/hepatitis G virus (GBV-C/HGV), has been cloned and characterised recently. GBV-C/HGV global epidemiology and risk factors for acquisition are currently unclear. We aimed to establish the determinants of this infection in a rural South African (SA) population. The study population included two samples, namely a community-based sample, and consenting persons from a nonspecialist outpatient department in the same district. A questionnaire regarding demographic details and putative risk factors was administered; blood samples were taken on which a polymerase chain reaction (PCR) was performed for both 5'NCR and NS5a regions of GBV-C/HGV using commercially available primers and probes. Two hundred and forty-nine people were studied with a mean GBV-C/HGV prevalence of 10.4%. Outpatient department and community prevalences differed significantly (18.0% and 6.3%, respectively, P = 0.004). GBV-C/HGV infection was associated with excessive alcohol consumption (P = 0.02; OR, 4.18) and a lack of waterborne sewerage (P = 0.04). PCR amplification of the NS5a region of all but two South African GBV-C/HGV positive samples showed poor reactivity. The prevalence of GBV-C/HGV in rural SA appears to be higher than that reported from Europe and North America. Infection appeared to be associated with excess alcohol intake and a history of previous blood transfusion. The discrepant NS5a and 5'NCR PCR sensitivity in this study raises the possibility of genetic differences in southern African GBV-C/HGV. PMID- 9365887 TI - Evidence for persistence of human parvovirus B19 DNA in bone marrow. AB - A nested polymerase chain reaction assay (nPCR) was used to investigate the potential of human parvovirus B19 DNA to persist in blood or bone marrow samples obtained either from blood donors or cadaveric bone donors or from patients presenting with clinical signs of parvovirus B19 infection. The presence of parvovirus B19 specific antibody in blood was tested by enzyme immunoassay (EIA). B19 virus genome was not detected in any blood sample of 115 blood donors, of whom 92 (80%) had anti-B19 IgG antibody only as an indication of past infection. In contrast; B19 virus DNA was detected in the bone marrow of 4 out of 45 bone donors. Each one of the serum samples available for 3 of these 4 individuals contained anti-B19 IgG antibody. Among 84 patients with clinical manifestations of parvovirus B19 infection, 17 (20%) had B19 virus DNA in bone marrow. Eight of the latter patients had anti-B19 IgG antibody in their blood but neither anti-B19 IgG nor B19 virus DNA. These data document the ability of parvovirus B19 DNA to persist in the bone marrow of asymptomatic individuals and patients with parvovirus B19 infection suspected on clinical grounds. PMID- 9365888 TI - Possible transmission of parvovirus B19 from intravenous immune globulin. AB - To look for genetic changes in human parvovirus B19 that might be associated with chronic infection, we sequenced B19 DNA obtained from serum specimens collected over an approximately 1-year period from a patient with systemic vasculitis. A comparison of the nucleotide sequences of the VP1/VP2 gene from four specimens revealed an abrupt change in the B19 genotype that coincided with initiation of intravenous immune globulin (IVIG) therapy. We suspect that one or more of the lots of IVIG administered to the patient were contaminated with B19. If true, this finding suggests that investigators must be careful in linking B19 infection to disease based on detection of B19 DNA in persons who have received multiple unit blood products. PMID- 9365889 TI - Sequence analysis of hepatitis C virus variants producing discrepant results with two different genotyping assays. AB - Methods for identifying the genotype of hepatitis C virus (HCV) in clinical specimens are frequently based upon the direct characterisation of viral RNA sequences by polymerase chain reaction (PCR) amplification, or by serologically based methods, in which the infecting genotype is inferred from the pattern of antibody reactivity to type-specific peptides or recombinant proteins used as antigens in an Enzyme Linked Immunosorbent Assay (ELISA). Although genotyping by direct, PCR-based methods show generally highly concordant results with the genotype inferred from serological typing assays (> 95% agreement), there exist a small number of samples that produce discrepant results. To investigate the underlying reasons for the discrepancies, we obtained eleven samples from haemophiliacs and four samples from patients with chronic hepatitis C that produced discordant results between a PCR based assay (InnoLipa I and II) and a serotyping assay (Murex HC02). Nucleotide sequences in the 5'noncoding region (5'NCR), core, and NS4 region were used to identify the genotype of the circulating virus and to identify amino acid changes in NS4 that might alter antigenicity. In 14 samples, sequence analysis of all three regions was concordant with the results of the InnoLipa assay. There were few if any amino acid substitutions in NS4 that might have accounted for the discrepant serotyping results, which were found predominantly in samples from individuals with a history of multiple exposure to HCV. It remains unclear whether the detection of antibody in such discrepant samples corresponds to previous expression of a different genotype than detected by PCR, or whether the virus population in plasma is more restricted in genotype diversity than the population in the liver or at other sites of viral replication. PMID- 9365890 TI - Non-isotopic detection of hepatitis C virus quasispecies by single strand conformation polymorphism. AB - In patients infected with the hepatitis C virus (HCV), a heterogeneous population of viruses, so-called quasispecies exists in vivo. The hypervariable regions (HVR) within the second envelope gene (HCV-E2) show particularly highly intratypic variability and are considered to be the target of neutralizing antibodies. The aims of the study were to optimize a genotype-independent primer set for amplification of HVR-1 and to establish a sensitive SSCP analysis for rapid and non-isotopic detection of predominant serum HCV quasispecies. Using the optimized SSCP technique, changes of quasispecies composition were investigated in five chronically infected patients with HCV before and during interferon-alpha treatment. HCV genotyping was performed by sequence and phylogenetic analysis. In addition, serial viremia and serum alanine aminotransferase (ALT) levels were determined. The SSCP analysis was performed at two time points before and during interferon-alpha therapy, respectively. Four patients showed an alteration of the SSCP pattern during the first three months of interferon-alpha therapy, whereas in one patient the SSCP pattern changed before therapy and remained stable during treatment with interferon-alpha. The present approach for non-isotopic analysis of single strand conformation polymorphism provides a direct, rapid, and sensitive technique for detection of the heterogeneous population of HCV quasispecies of different genotypes. Using this test procedure, investigations of large cohorts of patients with chronic hepatitis C can be undertaken. PMID- 9365891 TI - Detection of hepatitis C virus genomic sequences in the cerebrospinal fluid of HIV-infected patients. AB - To assess the presence of hepatitis C virus (HCV) in the central nervous system (CNS), HCV-RNA was sought in paired serum and cerebrospinal fluid (CSF) samples of 21 HIV/HCV-positive patients: HCV-RNA was detected in the serum of 19/21 patients (90.4%), and in the CSF of five of the 19 serum-positive patients. The presence of HCV-RNA was confirmed in follow-up CSF samples available for three of these five patients. An identical HCV genotype was found in the paired serum/CSF samples. No correlation was found between the different genotypes and the presence of HCV in CSF of the individual patients. HCV viremia levels measured by branched-DNA and quantitative PCR were not significantly higher in the CSF positive cases than in the CSF-negative cases (P = 0.3, using b-DNA; 0.5, using quantitative PCR). This report shows the presence of HCV in CSF and raises the possibility that the CNS may act as a reservoir site for HCV. PMID- 9365892 TI - Efficacy of immunization of high-risk infants against hepatitis B virus evaluated by polymerase chain reaction. AB - The polymerase chain reaction (PCR) is a rapid and very sensitive method to detect viral genomes. In the present study, the efficacy of immunization against hepatitis B virus (HBV) of high-risk infants was evaluated by PCR. Twenty-nine infants born to 24 HBeAg-positive carrier mothers were given hepatitis B immune globulin (HBIG) at birth and thereafter received repeated inoculations of plasma derived vaccine or HBIG, or both, within 1 year. Serum samples at 1 year following immunization were stored at -40 degrees C for later analysis using PCR to detect HBV-DNA. When HBV genomes were detected in infants, the DNA sequences in the S gene of HBV were determined. Of 29 infants, 2 were positive for HBV-DNA at the 1 year following immunization; one had the HBV containing only the wild type sequence in the S gene and became negative for HBV-DNA during the follow-up period. In contrast, another had the HBV, which contained nucleotide substitutions that altered the expression of the common group-specific determinant "a" of the S gene and resulted in clinical hepatitis with viral persistence. PCR analysis suggests that immunization against HBV prevents effectively high-risk infants from mother-to-child transmission. Even then, however, it is possible that amino acid substitutions in the "a" determinant of the S gene are associated with failure of conventional immunization against HBV. PMID- 9365893 TI - HIV-1 dynamics after transient antiretroviral therapy: implications for pathogenesis and clinical management. AB - Simple models of CD4 lymphocyte interactions with human immunodeficiency virus (HIV) lead to the hypothesis that progression of HIV infection involves an increase in viral replicative capacity, due either to changes in the virus or in the host environment, or both. In order to consider how changes in plasma virus load after transient, potent antiretroviral therapy can be used to test the above hypothesis--a simple mathematical model that encompasses the processes of (1) arrival of new CD4 lymphocytes, (2) death/removal of these cells by HIV independent mechanisms, (3) infection of susceptible CD4 lymphocytes by HIV, and (4) death/removal of infected cells was investigated. This showed that the in vivo rate of increase in plasma virus load immediately after transient therapy provides a measure of the viral replicative capacity. Thus, the hypothesis that progression of HIV infection involves an increase in viral replicative capacity can be tested by measuring this viral growth rate in patients with high CD4 counts and in patients with low CD4 counts. Studies should thus investigate dynamics of changes in virus levels after stopping antiretroviral therapy and, in particular, measure rates of increase in virus in patients at high and low CD4 counts. In practice, such data may assist in therapeutic management of patients with HIV infection. PMID- 9365894 TI - Sequential analyses of the mutations in the core upstream and precore regions of hepatitis B virus genome in anti-HBe positive-carriers developing acute exacerbation. AB - The nucleotide sequences of the core upstream and precore regions (371 nucleotide length, nt. 1604-1974) of hepatitis B virus (HBV) were analysed sequentially in three subjects who were positive serologically for anti-HBe and had acute clinical exacerbation after immunosuppressive treatment. These patients were asymptomatic HBV carriers before therapy. The results revealed that the mutant with an 8-bp deletion (nt. 1768-1775) located in the basic core promoter region was dominant in the asymptomatic HBV carrier phase in two of three subjects. After exacerbation, however, such mutant clones possessing 8-bp deletion disappeared or decreased in number and were replaced by the clones possessing a precore stop codon mutation G to A (nt. 1896) or by the clones possessing additional contiguous point mutations A to T (nt. 1762) and G to A (nt. 1764) and a new point mutation C to T (nt. 1653). Possible relationships between acute exacerbation of liver function accompanied by mutation and the transition of the dominant clones were discussed. PMID- 9365895 TI - Antibodies against enteroviruses in intravenous Ig preparations: great variation in titres and poor correlation with the incidence of circulating serotypes. AB - Antibody titres in immunoglobulin preparations for intravenous use were tested against 24 different enterovirus serotypes and varied between 1:100 and 1:10,000 within a single batch. Differences up to 8-fold were found for homologous titres between two different batches that were prepared 6 years apart. The lowest titre obtained was 1:40. The observed differences within and between the two batches could not be explained by different incidence of serotypes of enteroviruses circulating at the time blood was collected. Differences in titres of up to 18 fold were observed when several strains of the same serotype were tested suggesting that intratypic variation influences antibody titres. It is concluded that immunoglobulin preparations contain antibodies against many enteroviruses, but that titres can be low and cannot be predicted from the incidence of any particular serotype circulating in the community. Because of intratypic variation, selection of a batch for specific treatment should be based on results obtained with the patient's own isolate, and not with a reference strain. PMID- 9365896 TI - Detection rate and intratumoral virus load of human herpesvirus-8 in immunodeficiency-related B-cell lymphoid malignancies. AB - Human herpesvirus-8 (HHV-8), associated with Kaposi's sarcoma, primary effusion lymphoma, and Castleman's disease, has been found in circulating B-cells and might have a causative role in B-cell malignancies associated with immunodeficiency syndromes. We determined the rate of detection and intratumoral virus load of HHV-8 by means of a semiquantitative approach in post-transplant lymphoproliferative diseases (PTLDs), AIDS-related non-Hodgkin's lymphomas (NHLs), including both Burkitt's lymphomas (BLs) and large cell lymphomas (LCLs), as well as in control groups consisting of follicular hyperplasias (FHs) and HIV negative LCLs. HHV-8 sequences were detected at a similar rate in HIV-negative PTLDs (24%), HIV-negative LCLs (22%) and HIV-negative FHs (17%). The detection rate was significantly higher in HIV-positive BLs (73%), HIV-positive LCLs (67%), and HIV-positive FHs (65%) supporting the view of an epidemiological link between HHV-8 and HIV infections. The viral load was 10(2) genome copies per cell in the single case of primary effusion lymphoma included in the LCL group while it was 10(-3) copy per cell (median value; range: 10(-4)-10(-1)) in all the other HHV-8 positive samples. No significant difference of viral load was found according to HIV status. The virus loads of PTLDs and HIV-positive LCLs were significantly higher than those observed in HIV-positive BLs and FHs, suggesting, to some extent, that the degree of immunodeficiency may influence HHV-8 replication. However, with the exception of the single case of primary effusion lymphoma studied, the low intratumoral load of HHV-8 strongly argues against a direct causative agent of the virus in the occurrence of PTLDs and AIDS-related NHLs. PMID- 9365897 TI - Serum HBeAg quantitation during antiviral therapy for chronic hepatitis B. AB - Hepatitis Be antigen (HBeAg) seroconversion is considered the principal short term goal of antiviral therapy in chronic hepatitis B. To test whether the pre- and per-treatment HBeAg quantitation has a higher predictive value than that of hepatitis B virus DNA (HBV-DNA) quantitation for the outcome of antiviral therapy in chronic hepatitis B. A quantitative measurement of HBV-DNA and HBeAg (AxSYM HBe 2.0 Quantitative, Abbott Laboratories) was undertaken in serial serum samples from 30 patients with 16-week interferon-alpha (IFN-alpha) treatment (follow-up 36 weeks; 14 responders) and from 15 patients with 24-week lamivudine treatment (follow-up 24 weeks; 2 responders). In the group of interferon-treated patients, the median pretreatment HBV-DNA level was significantly lower in responders compared to nonresponders (P = 0.02); the difference in median HBeAg level was not significant. However, the percentage of response was significantly related (P = 0.003) to the magnitude of decline in HBeAg level between the start of therapy and week 4. This phenomenon was not observed for HBV-DNA. Using multivariate analysis, it was found that the fall of HBeAg levels between weeks 0 and 4 was the most important independent predictor of response. In the group of lamivudine treated patients, the rapid decline in HBV-DNA (> 90%) in 12 patients at week 4 had no relation to HBeAg seroconversion. In contrast, the fall in HBeAg-level (one patient with > 50% reduction at week 4 seroconverted) appears to be predictive. Quantitation of HBeAg at start and early during therapy may have clinically important predictive value for long-term response to antiviral therapy. PMID- 9365898 TI - Correlation between the detection of viral DNA by the polymerase chain reaction in peripheral blood leukocytes and serological responses to human herpesvirus 6, human herpesvirus 7, and cytomegalovirus in renal allograft recipients. AB - Diagnosis of significant infections by human herpesvirus 6 (HHV6) and 7 (HHV7) in transplant patients has proved difficult because both viruses are ubiquitous and can cause persistent infections in their hosts. The significance of viral DNA detected in peripheral blood leukocytes (PBLs; DNAemia) by PCR is therefore unclear. The interpretation of serological results is complicated by the fact that both primary and secondary infections with other herpesviruses may be associated with a concurrent antibody response to HHV6. Fifty-four renal allograft recipients were studied prospectively and their serological response to HHV6, HHV7 and CMV were compared with the detection of viral DNAemia from the homologous and heterologous viruses. Serum and heparinished blood samples were collected prospectively from 54 renal allograft recipients. DNA was extracted from PBLs and tested for the presence of HHV6, HHV7 and CMV DNA by PCR. Antibodies to HHV6 and HHV7 were measured by an indirect immunofluorescence test and to CMV by an anticomplement immunofluorescence (ACIF) test. CMV IgM antibodies were detected by a commercial enzyme immunoassay. CMV and HHV7 DNAemia were each significantly associated with serological responses to the homologous virus but no such association was found for HHV6 DNAemia. However, patients with consecutively positive DNAemia to any of the viruses (including HHV6) were more likely to have a homologous serological response. Patients who had detectable CMV IgM without a concurrent rise in CMV antibodies were significantly less likely to have CMV DNAemia (odds ratio = 0.16; 95% CI 0.02-0.9). CMV IgM antibodies may be associated with HHV6 or HHV7 DNAemia (odds ratio 2.3; 95% CI 0.5-15). This serological profile may reflect a crossreactive response to HHV6, HHV7 or other herpesviruses. CMV IgM should not be used in isolation for the diagnosis of CMV infection or disease in this group of patients. PMID- 9365899 TI - Human herpesvirus-6 and human herpesvirus-7 infections in bone marrow transplant recipients. AB - Human cytomegalovirus (HCMV), human herpesvirus-6 (HHV-6), and human herpesvirus 7 (HHV-7) DNA in peripheral blood leukocytes (PBL) of 61 bone marrow transplant recipients was monitored weekly during the first 12 weeks post-transplantation by a nested polymerase chain reaction (PCR). Thirty-seven (61%), 17 (28%), and 32 (53%) of patients had one or more PBL specimens positive for HCMV, HHV-6 or HHV-7 DNA, respectively. HHV-7 DNA in PBL during the early post-transplant period was associated with a longer time to neutrophil engraftment (mean 28.8 days vs 19.8 days; P = 0.01). In two patients who failed to engraft, HHV-6 DNA and HHV-7 DNA was detected in plasma and PBL, respectively, early in their post-transplant period. Patients with HCMV disease were more likely to have concurrent HHV-7 DNA in PBL prior to onset of disease than were patients with asymptomatic HCMV infection, suggesting that HHV-7 may be a cofactor in the progression from HCMV infection to HCMV disease. In the 17 patients (179 specimens) in whom viral DNA in plasma was studied (in addition to PBL), a positive result was found only in 3. In each, viral DNA in plasma appeared to correlate with clinically significant disease. HHV-7 DNA in plasma was associated with encephalitis in an allograft recipient. PMID- 9365900 TI - Human herpesvirus-6 (HHV-6)-associated necrotizing encephalitis in Griscelli's syndrome. AB - We report a male caucasian German pediatric patient of no Arab or Mediterranean ancestry with virus associated CNS lesions in Griscelli's syndrome (GS; McKusick No. 214450). The boy presented with recurrent infections, and meningitis with subsequent progressive signs of increased intracranial pressure leading to death at 32 weeks of age. At autopsy, various sites of the CNS revealed necroses in gray and white matter. CNS histology revealed numerous and massive predominantly perivascular CD8 positive lymphohistiocytic infiltrates. These findings were associated strictly with the presence of human herpesvirus-6 (HHV-6) genome or the HHV-6 specific late antigen H-AR 3, found in neurons, oligodendrocytes, and astrocytes. The search for HHV-6 replication dependent antigen, HHV-7 DNA, CMV, adenovirus, Coxsackie B1, B2, and B4-antigens, and mycobacteria was not successful. Detection of viruses was attempted using immunohistochemistry, in situ hybridization or nested polymerase chain reaction, respectively. Lymphocyte typing was carried out immunohistochemically. In GS, virus induced CNS damage does not seem to require necessarily active virus replication. It may also appear as a consequence of an immune reaction triggered by antigen expression. PMID- 9365901 TI - Voltage-dependent interaction between the muscarinic ACh receptor and proteins of the exocytic machinery. AB - 1. Release of neurotransmitter into the synaptic cleft is the last step in the chain of molecular events following the arrival of an action potential at the nerve terminal. The neurotransmitter exerts negative feedback on its own release. This inhibition would be most effective if exerted on the first step in this chain of events, i.e. a step that is mediated by membrane depolarization. Indeed, in numerous studies feedback inhibition was found to be voltage dependent. 2. The purpose of this study is to investigate whether the mechanism underlying feedback inhibition of transmitter release resides in interaction between the presynaptic autoreceptors and the exocytic apparatus, specifically the soluble NSF-attachment protein receptor (SNARE) complex. 3. Using rat synaptosomes we show that the muscarinic ACh autoreceptor (mAChR) is an integral component of the exocytic machinery. It interacts with syntaxin, synaptosomal-associated protein of 25 kDa (SNAP-25), vesicle-associated membrane protein (VAMP) and synaptotagmin as shown using both cross-linking and immunoprecipitation. 4. The interaction between mAChRs and both syntaxin and SNAP-25 is modulated by depolarization levels; binding is maximal at resting potential and disassembly occurs at higher depolarization. 5. This voltage-dependent interaction of mAChRs with the secretory core complex appears suitable for controlling the rapid, synchronous neurotransmitter release at nerve terminals. PMID- 9365902 TI - Inwardly rectifying, voltage-dependent and resting potassium currents in rat pancreatic acinar cells in primary culture. AB - 1. In exocrine pancreatic acinar cells in primary culture an inwardly rectifying, a voltage-dependent and a permanent resting K+ current were characterized. 2. Inwardly rectifying K+ currents could be elicited by elevation of the extracellular K+ concentration. The K+ inward currents were almost completely blocked by 5 mM Ba2+, whereas 10 mM TEA+ had only a partial effect. 3. Depolarizing voltage steps from negative clamp potentials evoked transient activation of a voltage-dependent K+ current. This voltage-dependent current could be blocked by 10 mM TEA+ and 1 mM 4-aminopyridine, but not by 5 mM Ba2+. 4. Neither the K+ inward rectifier nor the voltage-dependent K+ conductance produced a significant negative cell potential. Stable membrane potentials (-38.7 +/- 2.3 mV, n = 38) could only be recorded on cell clusters (> or = 5 cells). 5. Cell clusters, in contrast to single cells, had a permanent resting K+ conductance in addition to the inward rectifier and the voltage-dependent current. This resting K+ conductance was not blocked by TEA+, Ba2+, 4-aminopyridine or by the chromanol 293B. 6. Cytosolic alkalization by addition of NH4Cl to the bath solution decreased the resting K+ current. In parallel, electrical uncoupling of the cells and breakdown of the resting potential could be observed. The same effects could be produced when the cells were uncoupled by 0.2-1.0 mM n-octanol. It can be concluded that cell coupling is essential for maintenance of stable resting membrane potentials in pancreatic acinar cells. PMID- 9365903 TI - Effects of development and thyroid hormone on K+ currents and K+ channel gene expression in rat ventricle. AB - 1. In rat heart, three K+ channel genes that encode inactivating transient outward (ITO)-like currents are expressed. During development the predominant K+ channel mRNA species switches from Kv1.4 to Kv4.2 and Kv4.3. However, no functional correlate of this isoform switch has been reported. We investigated action potential characteristics and ITO in cultured neonatal rat ventricular myocytes and adult rat hearts. We further examined whether the changes in K+ channel gene expression and the associated electrophysiology that occurs during development could be induced by thyroid hormone. 2. In myocytes isolated from right ventricle of adult rat heart, action potential duration was short and independent of rate of stimulation. The density of ITO was 21.5 +/- 1.8 pA pF-1 (n = 21). Recovery from inactivation was best described by a single exponential (tau fast = 31.7 +/- 2.7 ms, n = 13). The current remaining at the end of a 500 ms pulse (ISUS) was 6.2 +/- 0.5 pA pF-1 (n = 19). 3. In contrast to adult cells, action potential duration was prolonged and was markedly rate dependent in cultured neonatal rat ventricular myocytes. The current density of ITO measured in cultured ventricular myocytes from 1- to 2-day-old rats was 10.1 +/- 1.5 pA pF 1 (n = 17). The recovery from inactivation for ITO was best described by the sum of two exponentials (tau fast = 64.3 +/- 8.8 ms, 54.4 +/- 10.2%; tau slow = 8216 +/- 2396 ms, 37.4 +/- 7.9%; n = 5). ISUS was 4.4 +/- 0.6 pA pF-1 (n = 17). Steady state activation and inactivation were similar in adult and neonatal ventricular myocytes. 4. In neonatal myocytes treated with thyroid hormone, tri-iodothyronine (T3, 100 nM), action potential duration was abbreviated and independent of stimulation rate. Whilst T3 did not significantly increase ITO density (24.0 +/- 2.9 pA pF-1; n = 21 in T3 treated cells cf. 20.1 +/- 3.0 pA pF-1; n = 37 in untreated controls), the recovery from inactivation of ITO was accelerated (tau fast = 39.2 +/- 3.6 ms, 82.2 +/- 8.9%, n = 9). T3 did however, increase ISUS current density (4.7 +/- 0.77 pA pF-1; n = 37 and 7.0 +/- 0.7 pA pF-1, n = 21, in control and T3 treated cells, respectively. 5. The effects of T3 (100 nM) were associated with a marked decrease in the expression of Kv1.4 at the mRNA and protein level, and an increase in the expression of Kv4.3 without changes in Kv4.2 mRNA levels. 6. The findings of the present study indicate that postnatal development involves a shortening of action potential duration and an increase in the density of ITO. Furthermore, we show that development is also associated with a loss of action potential rate dependence, and an acceleration in the rate of recovery of ITO. We propose that these functional effects occur as a consequence of the previously reported developmental Kv1.4 to Kv4.2/Kv4.3 isoform switch. In cultured neonatal myocytes, T3 induced many of the electrophysiological and molecular changes that normally occur during postnatal development, suggesting that this hormone may play an important role in postnatal electrophysiological development. PMID- 9365904 TI - Cation permeability of a cloned rat epithelial amiloride-sensitive Na+ channel. AB - 1. Conductance of heterotrimeric rat epithelial Na+ channels (alpha, beta, gamma rENaCs) for Li+ and Na+ in planar lipid bilayers was a non-linear function of ion concentration, with a maximum of 30.4 +/- 2.9 pS and 18.5 +/- 1.9 pS at 1 M Li+ and Na+, respectively. 2. The alpha, beta, gamma-rENaC conductance measured in symmetrical mixtures of Na(+)-Li+ (1 M) exhibited an anomalous mole fraction dependence, with a minimum at 4:1 Li+ to Na+ molar ratio. 3. Permeability ratios PK/PNa and PLi/PNa of the channel calculated from the bionic reversal potentials were dependent on ion concentration: PK/PNa was 0.11 +/- 0.01, and PLi/PNa was 1.6 +/- 0.3 at 50 mM; PK/PNa was 0.04 +/- 0.01 and PLi/PNa was 2.5 +/- 0.4 at 3 M, but differed from the ratios of single-channel conductances in symmetrical Li+, Na+ or K+ solutions. The permeability sequence determined by either method was Li+ > Na+ > K+ >> Rb+ Cs+. 4. Predictions of a model featuring two binding sites and three energy barriers (2S3B), and allowing double occupancy, developed on the basis of single ion current-voltage relationships, are in agreement with the observed conductance maximum in single ion experiments, conductance minimum in the mole fraction experiments, non-linearity of the current-voltage curves in bionic experiments, and the concentration dependence of permeability ratios. 5. Computer simulations using the 2S3B model recreate the ion concentration dependencies of single-channel conductance observed for the immunopurified bovine renal amiloride-sensitive Na+ channel, and short-circuit current in frog skin, thus supporting the hypothesis that ENaCs form a core conduction unit of epithelial Na+ channels. PMID- 9365906 TI - Actions of serum and plasma albumin on intracellular Ca2+ in human endothelial cells. AB - 1. The effects of serum and plasma albumin on [Ca2+]i in human endothelial cells were examined using single-cell Ca2+ imaging. Two types of endothelial cell were used: human umbilical vein endothelial cells (HUVEC) in primary culture, and the endothelial-derived cell line ECV304. 2. Serum albumin caused a large and transient rise in [Ca2+]i, due to Ca2+ release from an IP3-sensitive internal store, followed by a maintained elevation in [Ca2+]i attributable to Ca2+ influx from the external medium. A half-maximal rise in [Ca2+]i was produced by a concentration of serum albumin of about 1 microgram ml-1. 3. The Ca(2+)-releasing action of serum albumin is abolished by methanol extraction and is therefore attributable to an attached polar lipid. A possible candidate is lysophosphatidic acid, known to be released from platelets during blood coagulation, which produced similar effects to those of serum albumin. 4. In HUVEC, plasma albumin caused a sustained decrease in [Ca2+]i from the mean resting level of 114 nM to 58 nM. No effect of plasma albumin was observed in ECV304 cells. 5. The decrease in [Ca2+]i caused by plasma albumin is due to an uptake into intracellular stores. The store loading substantially potentiates the action of Ca(2+) releasing agonists such as histamine. 6. The results show that normal plasma albumin, which carries few lipids, lowers [Ca2+]i and potentiates the actions of Ca(2+)-releasing agonists by promoting Ca2+ uptake into intracellular stores. When converted to the serum form, by binding lysophosphatidic acid released during blood coagulation, albumin has a potent effect in elevating [Ca2+]i. Blood coagulation may therefore play a role in regulating vascular tone and capillary permeability. PMID- 9365905 TI - The role of Na(+)-Ca2+ exchange current in electrical restitution in ferret ventricular cells. AB - 1. The mechanisms underlying electrical restitution (recovery of action potential duration after a preceding beat) were investigated in ferret ventricular cells. The time to 80% recovery (t80) of action potential duration was approximately 204 ms. 2. At a holding potential of -80 mV, the Ca2+ current (ICa) reactivated and the delayed rectifier K+ current (IK) deactivated very rapidly (t80: approximately 32 and approximately 93 ms, respectively). The kinetics of both currents are too fast to account for electrical restitution alone. 3. The putative inward Na(+)-Ca2+ exchange current (INa-Ca) produced by the Na(+)-Ca2+ exchanger in response to the intracellular Ca2+ transient reprimed (t80: 189 ms) with the same time course as mechanical restitution (recovery of contraction) and with a similar time course to electrical restitution. 4. Substantial reduction of inward INa-Ca, by buffering intracellular Ca2+ with the acetyl methyl ester form of BAPTA, shortened the action potential and greatly altered the electrical restitution curve. Subsequent addition of nifedipine (to block ICa) or 4 aminopyridine (4-AP) (to block the transient outward current, ITO) further altered the electrical restitution curve. 5. Any time-dependent current that contributes to the action potential is likely to affect the time course of electrical restitution. Although ICa, IK and ITO were previously thought to be the only currents involved in electrical restitution, we conclude that inward INa Ca also plays an important role. PMID- 9365907 TI - Diadenosine polyphosphates evoke Ca2+ transients in guinea-pig brain via receptors distinct from those for ATP. AB - 1. The ability of diadenosine polyphosphates, namely P1,P2-di(adenosine) pyrophosphate (Ap2A), P1,P3-di(adenosine) triphosphate (Ap3A), P1,P4 di(adenosine) tetraphosphate (Ap4A), P1,P5-di(adenosine) pentaphosphate (Ap5A) and P1,P6-di(adenosine) hexaphosphate (Ap6A) to evoke Ca2+ signals in synaptosomes prepared from three different regions of the guinea-pig brain was examined. 2. In synaptosomal preparations from the paleocortex (cortex), diencephalon/brainstem (midbrain) and cerebellum all the dinucleotides evoked Ca2+ signals that were concentration dependent over the range 1-300 microM. ATP and its synthetic analogues, alpha,beta-methylene ATP, 2-methylthio ATP and adenosine 5'-O-(2-thio)diphosphate (all 100 microM) also evoked Ca2+ signals in these preparations. 3. In the midbrain and cerebellum preparations, responses to ATP and its analogues were attenuated or abolished by the P2 receptor antagonist suramin (100 microM) but responses to the dinucleotides were not. Also, desensitization by a dinucleotide blocked responses to dinucleotides but not mononucleotides, and desensitization by a mononucleotide blocked responses to mononucleotides but not dinucleotides. 4. In cortical preparations, suramin (100 microM) blocked responses to both classes of nucleotides. Furthermore, there was mutual cross-desensitization between the mono- and dinucleotides. 5. The adenosine A1 receptor antagonist, 8-cyclopentyl-1,3-dipropylxanthine, did not affect responses evoked by the dinucleotides, nor did the pyrimidine UTP. 6. It is concluded that there are specific dinucleotide receptors, activated by diadenosine polyphosphates, but not ATP or UTP, on synaptic terminals in guinea pig diencephalon/ brainstem and cerebellum. These receptors bear a similarity to the dinucleotide receptor (P4 receptor) in rat brain. In guinea-pig cerebral cortex synaptosomes, diadenosine polyphosphates appear to act via the same receptor as ATP. PMID- 9365908 TI - Muscarinic Ca2+ responses resistant to muscarinic antagonists at perisynaptic Schwann cells of the frog neuromuscular junction. AB - 1. Acetylcholine causes a rise of intracellular Ca2+ in perisynaptic Schwann cells (PSCs) of the frog neuromuscular junction. The signalling pathway was characterized using the fluorescent Ca2+ indicator fluo-3 and fluorescence microscopy. 2. Nicotinic antagonists had no effect on Ca2+ responses evoked by ACh and no Ca2+ responses were evoked with the nicotinic agonist nicotine. The muscarinic agonists muscarine and oxotremorine-M induced Ca2+ signals in PSCs. 3. Ca2+ responses remained unchanged when extracellular Ca2+ was removed, indicating that they are due to the release of Ca2+ from internal stores. Incubation with pertussis toxin did not alter the Ca2+ signals induced by muscarine, but did block depression of transmitter release induced by adenosine and prevented Ca2+ responses in PSCs induced by adenosine. 4. The general muscarinic antagonists atropine, quinuclidinyl benzilate and N-methyl-scopolamine failed to block Ca2+ responses to muscarinic agonists. Atropine (at 20,000-fold excess concentration) also failed to reduce the proportion of cells responding to a threshold muscarine concentration sufficient to cause responses in less than 50% of cells. Only the allosteric, non-specific blocker, gallamine (1-10 microM) was effective in blocking muscarine-induced Ca2+ responses. 5. In preparations denervated 7 days prior to experiments, low concentrations of atropine reversibly and completely blocked Ca2+ responses to muscarine. 6. The lack of blockade by general muscarinic antagonists in innervated, in situ preparations suggests that muscarinic Ca2+ responses at PSCs are not mediated by any of the five known muscarinic receptors or that post-translational modification prevented antagonist binding. PMID- 9365909 TI - Endothelium-dependent frequency modulation of Ca2+ signalling in individual vascular smooth muscle cells of the rat. AB - 1. We visualized intracellular Ca2+ concentration ([Ca2+]i) changes, using fluo-3 as an indicator, of individual vascular smooth muscle cells and endothelial cells within intact rat tail arteries by confocal microscopy. 2. Using a piezo-driven objective, we focused on endothelial and smooth muscle cell layers alternately to obtain Ca2+ images of their cells. In the presence of 1 microM acetylcholine (ACh), individual endothelial cells responded with intermittent increases in the [Ca2+]i (Ca2+ oscillations). At the same time, the frequency of Ca2+ oscillations in smooth muscle cells induced by electrical stimulation of the perivascular sympathetic nerve was greatly decreased. 3. A [Ca2+]i rise during the oscillations in the endothelial cells propagated in the form of a wave along the long axis of the cells. 4. In the presence of a NO synthase inhibitor, no significant inhibitory effect of ACh on the Ca2+ signalling in the vascular smooth muscle cells was detected, although the Ca2+ oscillations in the endothelial cells persisted. 5. The inhibitory effect of ACh on the frequency of Ca2+ oscillations in the vascular smooth muscle cells was mimicked by 1 microM sodium nitroprusside, a NO donor. 6. These results indicate that Ca2+ waves and oscillations in vascular endothelial cells regulate NO production, which modulates vascular tone by decreasing the frequency of Ca2+ oscillations in smooth muscle cells activated by sympathetic agonists. PMID- 9365910 TI - Action potential propagation into the presynaptic dendrites of rat mitral cells. AB - 1. Dendritic patch-clamp recordings were obtained from mitral cells in rat olfactory bulb slices, up to 350 microns from the soma. Simultaneous dendritic and somatic whole-cell recordings indicated that action potentials (APs) evoked by somatic or dendritic current injection were initiated near the soma. Both the large amplitude (100.7 +/- 1.1 mV) and the short duration (1.38 +/- 0.07 ms) of the AP were maintained as the AP propagated back into the primary mitral cell dendrites. 2. Outside-out patches isolated from mitral cell dendrites contained voltage-gated Na+ channels (peak conductance density, 90 pS micron-2 at -10 mV). When an AP was used as a somatic voltage-clamp command in the presence of 1 microM tetrodotoxin (TTX), the amplitude of the dendritic potential was attenuated to 48 +/- 14 mV. This shows that dendritic Na+ channels support the active back-propagation of APs. 3. Dendritic patches contained voltage-gated K+ channels with high density (conductance density, 513 pS micron-2 at 30 mV). Dendritic K+ currents were reduced to 35% by 1 mM external tetraethylammonium chloride (TEACl). When an AP was used as a somatic voltage-clamp command in the presence of TEACl, the dendritic potential was markedly prolonged. This indicates that dendritic K+ channels mediate the fast repolarization of dendritic APs. 4. We conclude that voltage-gated Na+ and K+ channels support dendritic APs with large amplitudes and short durations that may trigger fast transmitter release at dendrodendritic synapses in the olfactory bulb. PMID- 9365912 TI - Activation of NMDA receptors is necessary for the induction of associative long term potentiation in area CA1 of the rat hippocampal slice. AB - 1. It is commonly assumed that the role of the strongly activated heterosynaptic input during the induction of associative long-term potentiation (LTP) is to relieve the magnesium blockade of NMDA receptors located at the weakly stimulated synapses and thereby allow the weak input to undergo potentiation. We tested this assumption by using a caged form of the NMDA receptor antagonist, D-(-)-2-amino-5 phosphonopentanoic acid (D-AP5) to block the activation of NMDA receptors at the weak input in a conditioning protocol for the induction of associative LTP in area CA1 of the rat hippocampal slice. 2. The effect of releasing D-AP5 by flash photolysis of 100 microM caged D-AP5 (N-[1-(2-nitrophenyl)ethoxycarbonyl]-D-AP5) on pharmacologically isolated NMDA receptor-mediated field EPSPs was examined in area CA1. The slope of the EPSP was reduced by 71% within 50 ms of the initiation of the photolytic reaction when the concentration of released D-AP5 had reached 2.0-2.5 microM and was reduced by 95% within 1 min (10 microM D-AP5 released). 3. Associative LTP was induced by pairing a strong tetanus to one input with a weak tetanus (subthreshold for homosynaptic LTP) to a second input. The strong tetanus preceded the weak by 50 ms. Rapid application of D-AP5, by flash photolysis of caged D-AP5, coincident with the last shock of the strong tetanus, resulted in the blockade of NMDA receptor activation during the period of the weak tetanus. Associative LTP was blocked by photolysis of caged D-AP5 but was normally expressed in experiments using caged L-AP5. 4. We conclude that activation of NMDA receptors at the weakly activated input is an essential requirement for synaptically induced associative LTP. PMID- 9365911 TI - Mechanism underlying corticotropin-releasing hormone (CRH) triggered cytosolic Ca2+ rise in identified rat corticotrophs. AB - 1. The patch-clamp technique was used in conjunction with the fluorescent Ca2+ indicator indo-1 to measure simultaneously cytosolic Ca2+ concentration ([Ca2+]i) and membrane potential in single rat corticotrophs identified with the reverse haemolytic plaque assay. 2. Application of the adrenocorticotropin (ACTH) secretagogue, corticotropin-releasing hormone (CRH), triggered a sustained [Ca2+]i elevation and membrane depolarization. 3. The CRH action was mediated via the cAMP-dependent protein kinase cascade. Both the CRH-induced depolarization and [Ca2+]i elevation could be mimicked by extracellular application of the adenylate cyclase activator forskolin or the membrane-permeable cAMP analogue, 8 (4-chlorophenylthio)-adenosine-3',5'-cyclic monophosphate (8-CPT-cAMP). Intracellular adenosine cyclic 3',5'-(Rp)-phosphothioate (Rp-cAMPS), a protein kinase A inhibitor, abolished the CRH effects. 4. Voltage-clamp studies suggest that the CRH-triggered depolarization was due to the reduction of background K+ conductances. The CRH-sensitive current was Ca2+ independent and was insensitive to the K+ channel blockers tetraethylammonium (TEA) or 4-aminopyridine (4-AP), but could be partially inhibited by Ba2+. 5. The CRH-triggered steady-state depolarization stimulated extracellular Ca2+ entry via voltage-gated Ca2+ channels and raised [Ca2+]i. CRH failed to stimulate [Ca2+]i rise in cells that were voltage clamped at their resting potential. Removal of extracellular Ca2+ or inhibition of Ca2+ channels by Ni2+ abolished the [Ca2+]i rise. 6. Voltage-clamp studies of voltage-gated Ca2+ channels using Ba2+ as charge carrier show that approximately 90% of the channels were available for activation at the resting potential. CRH did not enhance the voltage-gated Ca2+ channels. PMID- 9365913 TI - Multiple modulatory effects of the neuroactive steroid pregnanolone on GABAA receptor in frog pituitary melanotrophs. AB - 1. The effects of the neuroactive steroid pregnanolone (5 beta-pregnan-3 alpha-ol 20-one) on the electrical response to GABA were investigated in cultured frog pituitary melanotrophs using the patch-clamp technique. 2. Low concentrations of pregnanolone (0.01-1 microM) in the extracellular solution enhanced the current evoked by submaximal concentrations of GABAA receptor agonists and prolonged the GABA-induced inhibition of the spontaneous action potentials in a dose-dependent manner. 3. Pregnanolone augmented the opening probability of the single GABA activated channels but did not modify the conductance levels. 4. Pregnanolone (1 microM) shifted the GABA dose-response curve towards the low GABA concentrations, reducing the EC50 from 4.2 to 1.8 microM. 5. Internal cell dialysis with pregnanolone (1 or 10 microM) did not alter the GABA-evoked current. 6. Pregnanolone accelerated the desensitization of both the current and conductance increases caused by GABA. 7. High concentrations of pregnanolone (30 microM) markedly and reversibly diminished the current evoked by 10 microM GABA. 8. At high concentrations (10-30 microM), pregnanolone induced an outward current which reversed at the chloride equilibrium potential. 9. It is concluded that, in frog pituitary melanotrophs, pregnanolone exerts a dual inverse modulation and a direct activation of the GABAA receptor-channel depending on the concentrations of both GABA and steroid. Pregnanolone acts on an extracellular site on the GABAA receptor inducing conformational changes of the receptor-channel complex, resulting in a desensitized less-conducting state. PMID- 9365914 TI - Functional identification of the input-output transforms of motoneurones in the rat and cat. AB - 1. We studied the responses of rat hypoglossal and cat lumbar motoneurones to a variety of excitatory and inhibitory injected current transients during repetitive discharge. The amplitudes and time courses of the transients were comparable to those of the synaptic currents underlying unitary and small compound postsynaptic potentials (PSPs) recorded in these cells. Poisson trains of ten of these excitatory and ten inhibitory current transients were combined with an additional independent, high-frequency random waveform to approximate band limited white noise. The white noise waveform was then superimposed on long duration (39 s) suprathreshold current steps. 2. We measured the effects of each of the current transients on motoneurone discharge by compiling peristimulus time histograms (PSTHs) between the times of occurrence of individual current transients and motoneurone discharges. We estimated the changes in membrane potential associated with each current transient by approximating the passive response of the motoneurone with a simple resistance-capacitance circuit. The relations between the features of these simulated PSPs and those of the PSTHs were similar to those reported previously for real PSPs: the short-latency PSTH peak (or trough) was generally longer than the initial phase of the PSP derivative, but shorter than the time course of the PSP itself. Linear models of the PSP to PSTH transform based on the PSP time course, the time derivative of the PSP, or a linear combination of the two parameters could not reproduce the full range of PSTH profiles observed. 3. We also used the responses of the motoneurones to the white noise stimulus to derive zero-, first- and second-order Wiener kernels, which provide a quantitative description of the relation between injected current and discharge probability. The convolution integral computed for an injected current waveform and the first-order Wiener kernel should provide the best linear prediction of the associated PSTH. This linear model provided good matches to the PSTHs associated with a wide range of current transients. However, for the largest amplitude current transients, a significant improvement in the PSTH match was often achieved by expanding the model to include the convolution of the second-order Wiener kernel with the input. 4. The overall transformation of current inputs into firing rate could be approximated by a second-order Wiener model, i.e. a cascade of a dynamic, linear filter followed by a static non linearity. At a given mean firing rate, the non-linear component of the response of the motoneurone could be described by the square of the linear component multiplied by a constant coefficient. The amplitude of the response of the linear component increased with the average firing rate, whereas the value of the multiplicative coefficient in the non-linear component decreased. As a result, the overall transform could be predicted from the mean firing rate and the linear impulse response, yielding a relatively simple, general description of the motoneurone input-output function. PMID- 9365915 TI - Effect of saponin treatment on the sarcoplasmic reticulum of rat, cane toad and crustacean (yabby) skeletal muscle. AB - 1. Mechanically skinned fibres from skeletal muscles of the rat, toad and yabby were used to investigate the effect of saponin treatment on sarcoplasmic reticulum (SR) Ca2+ loading properties. The SR was loaded submaximally under control conditions before and after treatment with saponin and SR Ca2+ was released with caffeine. 2. Treatment with 10 micrograms ml-1 saponin greatly reduced the SR Ca2+ loading ability of skinned fibres from the extensor digitorum longus muscle of the rat with a rate constant of 0.24 min-1. Saponin concentrations up to 150 micrograms ml-1 and increased exposure time up to 30 min did not further reduce the SR Ca2+ loading ability of the SR, which indicates that the inhibitory action of 10-150 micrograms ml-1 saponin is not dose dependent. The effect of saponin was also not dependent on the state of polarization of the transverse-tubular system. 3. Treatment with saponin at concentrations up to 100 micrograms ml-1 for 30 min did not affect the Ca2+ loading ability of SR in skinned skeletal muscle fibres from the twitch portion of the toad iliofibularis muscle but SR Ca2+ loading ability decreased markedly with a time constant of 0.22 min-1 in the presence of 150 micrograms ml-1 saponin. 4. The saponin dependent increase in permeability could be reversed in both rat and toad fibres by short treatment with 6 microM Ruthenium Red, a potent SR Ca2+ channel blocker, suggesting that saponin does affect the SR Ca2+ channel properties in mammalian and anuran skeletal muscle. 5. Treatment of skinned fibres of long sarcomere length (> 6 microns) from the claw muscle of the yabby (a freshwater decapod crustacean) with 10 micrograms ml-1 saponin for 30 min abolished the ability of the SR to load Ca2+, indicating that saponin affects differently the SR from skeletal muscles of mammals, anurans and crustaceans. 6. It is concluded that at relatively low concentrations, saponin causes inhibition of the skeletal SR Ca2+ loading ability in a species dependent manner, probably by increasing the Ca2+ loss through SR Ca2+ release channels. PMID- 9365916 TI - Functional electrical properties of the endothelium in lymphatic vessels of the guinea-pig mesentery. AB - 1. The resting and agonist-stimulated properties of endothelial cells and electrical communication between the endothelium and smooth muscle were investigated in open segments of guinea-pig mesenteric lymphatic vessels using intracellular microelectrodes. 2. Endothelial cells had a mean resting membrane potential (RMP) of -71.5 +/- 0.5 mV (n = 100) which was significantly different from the value of -60.8 +/- 1.1 mV (n = 75) recorded in smooth muscle. 3. Acetylcholine (ACh, 5-10 microM) generally evoked an initial hyperpolarization followed by depolarization (mean 3.4 +/- 0.5 mV and 15.4 +/- 1.0 mV, respectively, n = 75). 4. Ca(2+)-activated K+ channels were likely to underlie the ACh-induced hyperpolarization as this response exhibited an increased in membrane conductance, was larger in 0.5 mM K+ solution and was blocked by charybdotoxin (50 nM). 5. The endothelium did not exhibit a response to nitric oxide (NO) as the NO-donor sodium nitroprusside did not alter the RMP and the electrical responses to ACh were not affected by the NO-synthase inhibitor N omega-nitro L-arginine at a concentration which markedly inhibited smooth muscle hyperpolarization. 6. Electrical coupling between the endothelium and smooth muscle was not functional as there was extremely limited electrical continuity (1 in 12, endothelial/smooth muscle cell simultaneous recordings) and bradykinin, noradrenaline and isoprenaline caused different electrical responses in the two cell types. 7. These results provide the first description of RMP and electrical responses to various agonists in the lymphatic endothelium and its lack of functional electrical coupling with the smooth muscle. PMID- 9365917 TI - Effect of cardiopulmonary C fibre activation on the firing activity of ventral respiratory group neurones in the rat. AB - 1. Cardiopulmonary C fibre receptor stimulation elicits apnoea and rapid shallow breathing, but the effects on the firing activity of central respiratory neurones are not well understood. This study examined the responses of ventral respiratory group neurones: decrementing expiratory (Edec), augmenting expiratory (Eaug), and inspiratory (I) neurones during cardiopulmonary C fibre receptor-evoked apnoea and rapid shallow breathing. 2. Extracellular neuronal activity, phrenic nerve activity and arterial pressure were recorded in urethane-anaesthetized rats. Cardiopulmonary C fibre receptors were stimulated by right atrial injections of phenylbiguanide. Neurones were tested for antidromic activation from the contra- and ipsilateral ventral respiratory group (VRG), spinal cord and cervical vagus nerve. 3. Edec neurones discharged tonically during cardiopulmonary C fibre evoked apnoea and rapid shallow breathing, displaying increased burst durations, number of impulses per burst, and mean impulse frequencies. Edec neurones recovered either with the phrenic nerve activity (25 s) or much later (3 min). 4. By contrast, the firing activity of Eaug and most I neurones was decreased, featuring decreased burst durations and number of impulses per burst and increased interburst intervals. Eaug activity recovered in approximately 3 min and inspiratory activity in approximately 1 min. 5. The results indicate that cardiopulmonary C fibre receptor stimulation causes tonic firing of Edec neurones and decreases in Eaug and I neuronal activity coincident with apnoea or rapid shallow breathing. PMID- 9365918 TI - Actions of compounds manipulating the nitric oxide system in the cat primary visual cortex. AB - 1. We iontophoretically applied NG-nitro-L-arginine (L-NOArg), an inhibitor of nitric oxide synthase (NOS), to cells (n = 77) in area 17 of anaesthetized and paralysed cats while recording single-unit activity extracellularly. In twenty nine out of seventy-seven cells (38%), compounds altering NO levels affected visual responses. 2. In twenty-five out of twenty-nine cells, L-NOArg non selectively reduced visually elicited responses and spontaneous activity. These effects were reversed by co-application of L-arginine (L-Arg), which was without effect when applied alone. Application of the NO donor diethylamine-nitric oxide (DEA-NO) produced excitation in three out of eleven cells, all three cells showing suppression by L-NOArg. In ten cells the effect of the soluble analogue of cGMP, 8-bromo-cGMP, was tested. In three of those in which L-NOArg application reduced firing, 8-bromo-cGMP had an excitatory effect. In six out of fifteen cells tested, L-NOArg non-selectively reduced responses to NMDA and alpha-amino-3 hydroxy-5-methylisoxasole-4-propionic acid (AMPA). Again, co-application of L-Arg reversed this effect, without enhancing activity beyond control values. 3. In a further subpopulation of ten cells, L-NOArg decreased responses to ACh in five. 4. In four out of twenty-nine cells L-NOArg produced the opposite effect and increased visual responses. This was reversed by co-application of L-Arg. Some cells were also affected by 8-bromo-cGMP and DEA-NO in ways opposite to those described above. It is possible that the variety of effects seen here could also reflect trans-synaptic activation, or changes in local circuit activity. However, the most parsimonious explanation for our data is that NO differentially affects the activity of two populations of cortical cells, in the main causing a non specific excitation. PMID- 9365919 TI - Characterization of vagal pathways mediating gastric accommodation reflex in rats. AB - 1. We investigated the vagal pathways mediating the gastric accommodation reflex in the rat stomach. 2. Gastric distension (6 ml) evoked an increase of 9.0 +/- 1.0 cmH2O of intragastric pressure in vivo. Pretreatment with tetrodotoxin (TTX) caused a significant pressure increase by gastric distension, reaching 17.0 +/- 1.7 cmH2O, suggesting mediation by neural pathways. 3. The pressure increase evoked by gastric distension was significantly enhanced in vivo by acute truncal vagotomy (TV), hexamethonium (C6), and NG-nitro-L-arginine methyl ester (L-NAME), but not by vasoactive intestinal polypeptide (VIP) antiserum, guanethidine, or splanchnicotomy. 4. Gastric distension (6 ml) evoked a much larger intragastric pressure in the denervated, vascularly isolated, perfused rat stomach in vitro. Intra-arterial application of TTX and L-NAME did not cause further pressure increases evoked by gastric distension. 5. The pressure increase evoked by gastric distension remained high 2 weeks after TV in vivo. However, the accommodation reflex was fully restored 4 weeks after TV in vivo. This reflex was antagonized by TTX, C6 and L-NAME, but not by VIP antiserum, guanethidine and splanchnicotomy. 6. Similar to in vivo studies, gastric distension caused a smaller increase in intragastric pressure in response to gastric distension in the denervated, vascularly isolated, perfused stomach obtained from rats 4 weeks after vagotomies in vitro. The pressure increase evoked by gastric distension was significantly enhanced by L-NAME, hexamethonium and TTX. 7. It is suggested that the vago-vagal reflex plays an important role in mediating the accommodation reflex. This involves a vagal efferent pathway that uses nitric oxide as a final neurotransmitter mediating gastric relaxation in intact rats. It is also suggested that the adaptive mechanism mediating the accommodation reflex following vagotomy occurs in the gastric myenteric plexus. PMID- 9365920 TI - Dissociation between lactate and proton exchange in muscle during intense exercise in man. AB - 1. Transport of lactate, H+ and fluid across muscle sarcolemma was studied in contracting muscles under varying blood acid-base conditions. 2. Subjects performed two-legged submaximal knee-extensor exercise for 29-35 min consisting of warming up for 5 min followed by 10 min of leg exercise (L1), leg and arm exercise for 6-10 min (L2 + A) and leg exercise for 10 min (L3). The experimental protocol was performed on two occasions; inspiring air (normoxia, N) or breathing 14% O2 in N2 (hypoxia, H). Leg blood flow was measured and femoral arterial and venous blood was sampled before and during each phase of exercise. 3. Arterial blood lactate concentration increased progressively during exercise to 5.9 +/- 0.8 (N) and 8.2 +/- 0.8 mmol l-1 (H) (P < 0.05) after 5.5 min of L2 + A. Arterial blood pH was higher (P < 0.05) in H than in N, whereas arterial blood HCO3- concentrations were the same. Leg lactate release was higher in H than in N (3.1 +/- 0.7 vs. 2.0 mmol l-1 (P < 0.05) during L1. In L2 + A a net uptake of lactate was observed in both N and H. The concentration of lactate in the red blood cells increased during exercise to 2.3 +/- 0.4 (N) and 4.3 +/- 0.7 mmol l-1 (H) (P < 0.05) after 5.5 min of L2 + A, but no red blood cell femoral arterial-venous lactate difference was observed. 4. Net proton release, estimated from actual base excess (ABE) adjusted for changes in reduced haemoglobin, was significant (P < 0.05) both at rest and during each phase of exercise. Furthermore, the difference between net proton and lactate release was positive throughout exercise and of similar magnitude in N and H. 5. The present data suggest that (1) H+ exchange in muscle during submaximal exercise can to a large extent occur through mechanisms other than via coupling to lactate; (2) muscle transport of H+ is insensitive to changes in blood pH in the range of 0.02-0.08 pH units; (3) transport of lactate across the membrane of red blood cells appears to be of minor importance for lactate release from active muscles. PMID- 9365921 TI - An improved rapid method for selecting monoclonal antibodies with high catalytic activities. AB - Monoclonal antibodies were raised against a beta-naphthyl phosphonate hapten (1) to elicit antibodies capable of catalyzing the hydrolysis of beta-naphthyl acetate (3). After cell fusion, potential catalytic antibody-producing hybridomas were selected, by use of a competitive inhibition assay on the basis of the binding activity for a short transition-state analogue (inhibitor 5), followed by use of high-performance liquid chromatography analysis for the hybridoma supernatants to screen the antibodies processing catalytic activities. It was shown that supernatants of 12 wells had high binding activity with inhibitor and of them, 7 had catalytic activities. After cloning by limiting dilution, we got two hybridoma clones producing monoclonal antibodies which catalyzed the hydrolysis of beta-naphthyl acetate. This combination of competitive inhibition assay with high-performance liquid chromatography analysis represents an improved rapid approach for the screening of potential catalytic antibodies and significantly increases the possibility of obtaining efficient catalytic monoclonal antibodies. Further study of the catalytic antibodies revealed significant rate enhancement (Kcat/K(uncat) approximately 10(6) and specificity. PMID- 9365923 TI - The unusual amino acid triplet Asn-Ile-Cys is a glycosylation consensus site in human alpha-lactalbumin. AB - Human alpha-lactalbumin has not been described as a glycoprotein, despite the fact that several alpha-lactalbumins of both ruminant and nonruminant species are known to be glycosylated. In all these species the glycosylation site is the 45Asn in the usual triplet 45Asn-Gly/Gln-47Ser. We have found that human alpha lactalbumin is glycosylated and the glycosylation site has been determined by protein sequencing and mass spectrometry. We report an unusual glycosylation site at 71Asn in the triplet 71Asn-Ile-73Cys, which is conserved in all known alpha lactalbumins except red-necked wallaby. That a relatively small proportion of the protein is glycosylated (about 1%) may reflect the importance of this region of the protein sequence to the molten globule state of alpha-lactalbumin. PMID- 9365924 TI - Spectroscopic characterization of arrestin interactions with competitive ligands: study of heparin and phytic acid binding. AB - A combination of intrinsic fluorescence and circular dichroic (CD) spectroscopy has been used to characterize the complexes formed between bovine retinal arrestin and heparin or phytic acid, two ligands that are known to mimic the structural changes in arrestin attending receptor binding. No changes in the CD spectra were observed upon ligand binding, nor did the degree of tryptophan fluorescence quenching change significantly in the complexes. These data argue against any large-scale changes in protein secondary or tertiary structure accompanying ligand binding. The change in tyrosine fluorescence intensity was used to determine the dissociation constants for the heparin and phytic acid complexes of arrestin. The only change observed was a saturable diminution of tyrosine fluorescence signal from the protein. For both ligands, the data suggest two distinct binding interactions with the protein--a high--affinity interaction with Kd between 200 and 300 nM, and a lower affinity interaction with Kd between 2 and 8 microM. Study of collisional quenching of tyrosine fluorescence in free arrestin and the ligand-replete complexes indicates that 10 of the 14 tyrosine residues of the protein are solvent-exposed in the free protein; this value drops to between 5 and 6 solvent-exposed residues in the high-affinity complexes of the two ligands. These data suggest that ligand binding leads to direct occlusion of between 4 and 5 tyrosine residues on the solvent-exposed surface of the protein, but not to any large-scale changes in protein structure. The large activation energy previously reported to be associated with arrestin-receptor interactions may therefore reflect localized movements of the N- and C-termini of arrestin, which are proposed to interact in the free protein through electrostatic interactions. Binding of the anionic ligands heparin, phytic acid, or phosphorylated rhodopsin may compete with the C-terminus of arrestin for these electrostatic interactions, thus allowing the C-terminus to swing out of the binding region. PMID- 9365922 TI - Cross-linking of fibronectin to C-terminal fragments of the fibrinogen alpha chain by factor XIIIa. AB - Fibronectin binds specifically to fibrin and is covalently cross-linked to the fibrin alpha chain by activated factor XIII (XIIIa). This reaction is important for wound healing. Here we investigate XIIIa-catalyzed cross-linking of fibronectin and some of its fragments to a recombinant fragment representing the COOH-terminal 30 kDa of the fibrin alpha chain (alpha C30K:His 368-Val 610). Only fibronectin and those fragments containing an intact NH2-terminus were able to form cross-linked complexes. As many as 10 of the 17 lysines in alpha C30K can serve as amine donors in this reaction. Analysis of the rate of XIIIa-catalyzed cross-linking of fibronectin NH2-terminal peptides and fragments with alpha C30K revealed that the presence of the first type I "finger" module accelerates the cross-linking reaction; addition of fingers 2-5 had no further effect. PMID- 9365925 TI - Prediction of the tertiary structure of the complement control protein module. AB - Complement control protein (CCP) modules, or short consensus repeats (SCR), exist in a wide variety of complement and adhesion proteins, principally the selectins. We have predicted the three-dimensional structure of a CCP module based upon secondary structural information derived by two-dimensional NMR [Barlow et al. (1991), Biochemistry 30, 997-1004]. Accordingly, the CCP is predicted to contain seven beta-strands with extensive hydrogen-bonding interactions, and shows a compact, globular structure. Comparison of this model to the X-ray structure of a kringle domain suggests that the CCP unit is more compact than a kringle structure, and that despite their similarities in size and disulfide bond format, the two are not homologous. Although the function of CCP domains is unknown, it is hoped that the structural model presented herein will facilitate further inquiry into how they contribute to so many systems of biological importance. PMID- 9365926 TI - Sequential main-chain proton and carbon resonance assignments for wild-type yeast iso-1 ferrocytochrome c and identification of secondary structural elements. AB - Yeast iso-1 cytochrome c is a naturally occurring protein that possesses an unusually reactive Cys102 that imbues iso-1 with a complicated solution chemistry which includes spontaneous dimerization and poorly characterized redox reactions. For this reason previous studies of this typical member of the c-type cytochromes have been relegated to variant proteins in which the 102 position has been mutated, with most common changes involving serine and threonine. However, we have determined sequential 1H resonance assignments for the wild-type native protein because it is the actual participant in yeast mitochondrial electron transfer processes and because the wild-type native protein should be the fundamental assignment basis. In addition to 1H resonance assignments for 97 of 106 amino acids, we have also provided an extensive database of long-range NOEs. Comparison of these NOEs and a chemical shift index based upon alpha-H resonances has lead to identification of solution secondary structural elements that are consistent with the solid-state crystal structure. Although there is currently no efficient expression system that would facilitate isotope labeling of iso-1 cytochrome c, we tried to assess the usefulness of future heteronuclear experiments by using natural-abundance 1H/13C HMQC experiments to unambiguously assign 35 alpha-C resonances. PMID- 9365927 TI - Covalent structure of botulinum neurotoxin type E: location of sulfhydryl groups, and disulfide bridges and identification of C-termini of light and heavy chains. AB - Botulinum neurotoxin (NT) serotype E is synthesized by Clostridium botulinum as an approximately 150-kDa single-chain polypeptide of 1252 amino acid residues of which 8 are Cys residues [Puolet et al. (1992); Biochem. Biophys. Res. Commun. 183, 107-113]. The posttranslational processing of the gene product removes only the initiating methionine. A very narrow segment of this 1251-residue-long mature protein--at one-third the distance from the N-terminus (between residues Lys 418 and Arg 421)--is highly sensitive to proteases, such as trypsin. The single-chain NT easily undergoes an exogenous posttranslational modification by trypsin; residues 419-421 (Gly-Ile-Arg) are excised. The proteolytically processed NT is a dichain protein in which Pro 1-Lys 418 constitute the approximately 50-kDa light chain, Lys 422-Lys 1251 constitute the approximately 100-kDa heavy chain; Cys 411 Cys 425 and Cys 1196-Cys 1237 form the interchain and intrachain disulfide bonds, respectively; the other four Cys residues at positions 25, 346, 941, and 1035 remain as free sulfhydryl groups. The approximately 150-kDa dichain NT, and separated light and heavy chains, were fragmented with CNBr and endoproteases (pepsin and clostripain); some of these fragments were carboxymethylated with iodoacetamide (with or without 14C label) before and after fragmentation. The fragments were separated and analyzed for amino acid compositions and sequences by Edman degradation to determine the complete covalent structure of the dichain type E NT. A total of 208 amino acid residues, i.e., 16.5% of the entire protein's sequence deduced from nucleotide sequence, was identified. Direct chemical identification of these amino acids was in complete agreement with that deduced from nucleotide sequence. PMID- 9365928 TI - Kinetics of thermal inactivation of lactate dehydrogenase from rabbit muscle. AB - The kinetics of thermal inactivation of rabbit muscle lactate dehydrogenase at different temperatures has been studied using the kinetic method for the substrate reaction during irreversible inhibition of enzyme activity previously described by Tsou [Adv. Enzymol. Relat. Areas Mol. Biol. (1988), 61, 381-436]. The results show that thermal inactivation of the enzyme is an irreversible reaction. Microscopic rate constants were determined for thermal inactivation of the free enzyme and the enzyme-substrate complex. The inactivation rate constant of the free enzyme is much larger than the rate constant of the enzyme-substrate complex. The results suggest that the presence of the substrate has a certain protective effect against thermal inactivation of the enzyme. PMID- 9365929 TI - Purification, properties, and N-terminal amino acid sequence of a kallikrein-like enzyme from the venom of Lachesis muta rhombeata (Bushmaster). AB - Pit viper venoms contain multiple proteinases which cause considerable damage in tissues and systemic effects after envenomation. A proteinase, kallikrein-like enzyme, belonging to the serine group must play a very important role on systemic effects. The corresponding enzyme from Lachesis muta rhombeata venom was purified to homogeneity by a combination of isoelectrofocusing fractionation followed by one step of gel filtration HPLC. The enzyme focused with pI 5.0-6.5, it had a molecular mass of 32 kDa by gel filtration HPLC, had edematogenic activity, and induced a hypotensic effect in anesthetized rats. It exhibited strong N-alpha tosyl-L-Arg methyl esterase (955.38 units/mg) and N-Bz-DL-Arg-pNA amidolytic (233.02 units/mg) activities, hydrolyzed tripeptide nitroanilide derivatives weakly or not at all, and cleaved selectively the A-alpha and B-beta chains of fibrinogen, apparently leaving the Y-chain unaffected. The 30 N-terminal amino acid sequence of the L. m. rhombeata protein showed greatest identity (74% in 26 amino acids) with Crotalus viridis kallikrein-like protein, but significant similarities in sequence were observed with enzymes from other snake venoms and pig pancreatic kallikrein. PMID- 9365930 TI - Assessment of the interaction between urokinase and reactive site mutants of protein C inhibitor. AB - Urokinase-type plasminogen activator (uPA) is a serine protease involved in pericellular proteolysis and tumor cell metastasis via plasmin-mediated degradation of extracellular matrix proteins. Plasma uPA is inhibited by the serine protease inhibitor protein C inhibitor (PCI) by the insertion of PCI's reactive site loop into the active site of the protease. To better understand the structural aspects of this inhibition, 15 reactive-site mutants of recombinant PCI (rPCI) were assayed for differences in uPA inhibition. These assays revealed that substitutions at the P1 Arg354 and P3 Thr352 sites of rPCI were detrimental to inhibitory activity, while P3' Arg357 mutations had little effect upon the inhibition rate. However, replacement of the P2 Phe353 with small residues like Ala and Gly increased the effectiveness of rPCI three- to four fold. To explain these altered rates of inhibition, a computer-derived molecular model of uPA was generated and docked to a model of PCI to simulate complex formation. The changes made by mutagenesis were then recreated in the model of uPA-PCI. In accordance with the kinetic data, the poor performance of P3 variants is primarily attributable to charge repulsion, while alleviation of steric hindrance at P2 produces the observed increase in uPA inhibition. In the model, residues at P3' interact with PCI rather than uPA, consistent with P3' variants demonstrating that little variation from wild-type activity. Ultimately, this combination of mutagenesis and molecular modeling will further refine our understanding of the interaction between PCI and uPA. PMID- 9365931 TI - Protein kinase C regulation of ATP-induced phosphoinositide hydrolysis in bovine aorta endothelial cells. AB - This study investigated the mechanism of protein kinase C-mediated inhibition of ATP-induced phospholipase C activation in cultured bovine aorta endothelial cells (BAEC). In BAEC labeled with 3H-inositol, phorbol myristate acetate (PMA) prevented ATP-induced inositol bisphosphate and inositol trisphosphate formation. In membranes prepared from these PMA-treated cells, Ca(2+)-, sodium fluoride-, GTP gamma S-, and ATP plus GTP gamma S-stimulated inositol bisphosphate, but not inositol trisphosphate, formation was inhibited. Inositol trisphosphate phosphatase activity was not altered in membranes from PMA-treated BAEC. These results suggest that 1) protein kinase C inhibits ATP-induced phospholipase C activation in BAEC through interference with the coupling of phospholipase C with a G-protein and through an effect on phospholipase C itself, and 2) different mechanisms are responsible for the inhibition by protein kinase C of the phospholipase C-mediated hydrolysis of phosphatidylinositol bisphosphate and phosphatidyl-inositol phosphate. PMID- 9365932 TI - Evidence for alternative splicing in hepatic alpha 1B-adrenergic receptor gene expression. AB - The interactions of catecholamines with alpha 1B-adrenergic receptors (alpha 1B AR) located on the surface of many cell types are responsible for physiologic and pathologic functions in mammalian systems. Transcription of the alpha 1B-AR gene leads to the expression of multiple alpha 1B-AR mRNAs that are distributed in a tissue-specific fashion. The purpose of this study was to define the 5' untranslated regions of the multiple alpha 1B-AR gene transcripts. Evidence for a previously unidentified intron in the alpha 1B-AR gene upstream of the receptor open reading frame was obtained via rapid amplification of cDNA ends. A product was amplified and was found to be missing the nucleotide interval from -708 to 194, (+1 is the start of translation). Evidence for tissue-specific alternative intron splicing was obtained from ribonuclease protection assays and RT-PCR experiments. Using an RNA probe extending from -240 to +93 and including 45 nucleotides into the putative intron, a single protected fragment was detected in heart RNA while two protected fragments were detected in liver RNA. RT-PCR amplification of the region spanning the intron resulted in detection of two PCR products in liver RNA and no detectable product in heart RNA. These findings emphasize the complexity of alpha 1B-AR gene regulation and suggest that multiple alpha 1B-AR mRNAs with different 5'-UTRs may play a role in regulating alpha 1B adrenergic responsiveness. PMID- 9365933 TI - Decrease of hormone binding capacity of estrogen receptor by calcium. AB - We have addressed the question as to whether calcium may modify the [3H]estradiol ([3H]E2) binding properties of the estrogen receptor (ER). A human recombinant full length ER (yER) expressed in yeast was used to limit the potential interference of ER-associated proteins and proteases present in the target tissues. Ca++ (0.1-10 mM) always produced an important loss of [3H]E2 binding capacity without any effect on the hormone binding affinity of residual receptors. This loss was reflected in a decrease of immunoreactivity for monoclonal antibodies raised against the hormone binding domain. An ER recombinant expressing solely this domain confirmed that the ion operated at this level. Binding of [125I]Z-17 alpha-(2-iodovinyl)-11 beta-chloromethyl estradiol 17 beta (an compound with very high selectivity for ER) as well as [125I]tamoxifen aziridine were similarly affected. Size-exclusion chromatography failed to reveal the emergence of any ER isoforms of low molecular weight rejecting the hypothesis of a Ca(++)-induced proteolysis. In agreement with this conclusion, EDTA reversed the loss of [3H]E2 binding capacity. Phosphoamino acids (PY, PT and PS) partly antagonized the effect of Ca++ suggesting its interaction with phosphoamino acid residues. Worthy of note, the effect of Ca++ appeared more marked when assessed by DCC than HAP assay. The phosphocalcic nature of the HAP matrix may explain this phenomenon which was observed with cytosolic ER from various origins. PMID- 9365934 TI - A structural rationale for the design of water soluble peptide-derived neurokinin 1 antagonists. AB - Molecular models of a pharmacophore for NK1 neurokinin antagonists and of ligand receptor complexes for the human NK1 G protein-coupled receptor are presented. The models develop a structural rationale for the discovery of the recently described highly potent peptidomimetic NK1 antagonists S18523 and S19752 which were designed to be water soluble. Water solubility was conferred on these compounds by introduction of an anionic butyl-tetrazole substituent on the scaffold of dipeptide-derived NK1 antagonist analogues. The models provide convincing evidence that the anionic butyl-tetrazole moieties of S18523 and S19752 protrude outside the membrane-spanning domain of the receptor and do not interfere significantly with the core of the antagonist binding site. It is emphasized that this result could only be obtained through the combination of the two modelling approaches. The result suggest a general way to modify the transport properties of the peptidomimetic antagonists without altering the receptor-binding interaction, and it outlines the potential of including the combination of pharmacophore models and crude models of receptor-ligand complexes early in the drug design process. PMID- 9365935 TI - Research at zoos and aquariums: regulations and reality. PMID- 9365936 TI - In vitro maturation and fertilization of oocytes recovered from free-ranging Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae). AB - A noninvasive repeatable method to harvest oocytes for in vitro fertilization (IVF) could potentially be used to assist reproduction in endangered equid species. The objectives of this study were to evaluate a specific transvaginal ultrasound-guided oocyte recovery procedure for use in zebra mares and the general applicability of IVF procedures in zebra. Ovaries were collected from Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae) mares at routine culling for Expt. I. Of the 144 oocytes recovered from these ovaries, 70% were of excellent quality. No significant difference in oocyte quality was found between the two zebra species. Zona drilling was performed on in vitro-matured oocytes prior to IVF. Epididymal sperm from culled Burchell's zebra stallions were used for IVF. The sperm either were exposed to calcium ionophore or were not treated and served as a control. In vitro fertilized oocytes were then co-cultured with zebra granulosa cells (ZGC) or with bovine oviduct cells (BOC) for up to 8 days. Overall, a 38% cleavage rate was obtained with 16% of sperm-exposed oocytes developing to the morula or blastocyst stage. All of the embryos that developed to at least the morula stage were cultured on BOC; whereas, none of those cultured on ZGC reached the morula stage during the same interval. Cleavage rates of oocytes inseminated with ionophore-treated or with control sperm were not significantly different, suggesting that ionophore treatment of epididymal sperm for IVF in these zebra species may be redundant. In Expt. II, 10 transvaginal ultrasound-guided oocyte aspiration procedures on five captive Burchell's zebra mares recovered a total of 33 oocytes (6.6 oocytes/female) of which 94% were considered viable. This approach may be an attractive means of producing gametes for assisted reproduction in endangered species. Furthermore, results from this study indicate that IVF may become a means of producing offspring from zebra and other equid species in the future. PMID- 9365938 TI - Observations on the female reproductive cycle of captive giant tortoises (Geochelone spp.) using ultrasound scanning. AB - The reproductive activities of one adult female Galapagos tortoise (Geochelone nigra) and three adult female Aldabra tortoises (Geochelone gigantea) were monitored over 2 yr using ultrasound scanning. A nonrestraining technique of tactile stimulation was used for all examinations. Developing, preovulatory, and atretic ovarian follicles, as well as eggs at various stages of shell deposition, were identified and measured. In G. nigra, follicles became preovulatory at a diameter of 40-42 mm and eggs were laid 34-84 days (mean = 55.6, n = 5) after the thin-shelled eggs were first detected in the oviducts. Geochelone nigra was capable of retaining eggs, with the shell already formed, until the next breeding season. No eggs have been produced by G. gigantea during their stay in Zurich Zoo although follicles of 38-40 mm have been observed frequently in two animals. PMID- 9365937 TI - Treatment of gastritis in cheetahs (Acinonyx jubatus). AB - Three cheetahs (Acinonyx jubatus) had a clinical history of chronic spiral bacteria-associated gastritis and three cheetahs had no clinical history of gastritis. Gastric biopsies were obtained from all six cheetahs prior to treatment for gastritis and 3 wk and 1 yr posttreatment. The cheetahs were treated with tetracycline hydrochloride 500 mg p.o. q.i.d., metronidazole 250 mg p.o. q.i.d., and bismuth subsalicylate 300 mg p.o. q.i.d. Each drug was administered concurrently for 7 days. Following this treatment, each cheetah was maintained on 300 mg bismuth subsalicylate p.o. s.i.d. for 1 yr. The three cheetahs with a history of gastritis were culture positive for Helicobacter acinonyx and remained positive during the entire study. The three cheetahs with no clinical history of gastritis were culture negative for H. acinonyx, but gastric biopsies revealed Gastrospirillum-like bacteria (tentatively named Helicobacter heilmannii) pretreatment. Gastric biopsies were negative for H. heilmannii on subsequent examinations. Although the treatment did not eradicate H. acinonyx, it did provide symptomatic relief from the vomiting, anorexia, and weight loss associated with clinical gastritis. The use of endoscopically guided gastric mucosal biopsies for urease testing and histopathologic examination of Warthin-Starry-stained sections is a sensitive and specific method of diagnosing spiral bacteria-associated gastritis. Treatment of spiral bacteria-associated gastritis in cheetahs should include the rational use of antibiotics (tetracycline or amoxicillin and metronidazole), bismuth compounds, and omeprazole and evaluation of husbandry methods to reduce stress. PMID- 9365939 TI - A comparison of sevoflurane and isoflurane for short-term anesthesia in polecats (Mustela eversmanni). AB - Twenty-four Siberian polecats (Mustela eversmanni) from 12 litters were anesthetized with either inhaled sevoflurane or isoflurane. With 7% delivered sevoflurane and 5% delivered isoflurane, time to loss of righting reflex (mean +/ SE) with sevoflurane (1.9 +/- 0.1 min) was significantly shorter compared with isoflurane (2.6 +/- 0.1 min). During maintenance at a light plane of anesthesia, systolic arterial pressure was significantly higher with sevoflurane (83 +/- 2 mm Hg) compared with isoflurane (66 +/- 2 mm Hg), and heart rate was significantly lower with sevoflurane (191 +/- 3 beats/min) compared with isoflurane (204 +/- 3 beats/min). There was no difference in respiratory rate jugular venous pH, pCO3, HCO3-, base excess, or recovery of righting reflex. Induction of anesthesia is more rapid and blood pressure is better maintained with sevoflurane compared with isoflurane; therefore, sevoflurane may be less stressful and safer. Inhaled sevoflurane should be an appropriate anesthetic for black-footed ferrets (Mustela nigripes) in laboratory and field conditions. PMID- 9365940 TI - Meningoencephalitis in capercaillie (Tetrao urogallus L.) caused by a Sarcocystis like organism. AB - A nonsuppurative meningoencephalitis, previously presumed to be toxoplasmosis, was found in 53 capercaillies (Tetrao urogallus L.) examined at necropsy at the National Veterinary Institute, Uppsala, Sweden, between 1966 and 1985. Pronounced meningitis and encephalitis with perivascular cuffs of mononuclear inflammatory cells as well as focal gliosis were prominent histopathologic findings. Protozoa were frequently associated with these lesions. Ultrastructurally, the protozoa appeared to divide by endopolygeny, and merozoites had no rhoptries. Organisms from all 12 birds subjected to Sarcocystis cruzi immunohistochemical staining reacted positively but did not react to Toxoplasma gondii antiserum. The agent was, therefore, assigned to the family Sarcocystidae and was probably more closely related to species of the genus Sarcocystis than to T. gondii. PMID- 9365941 TI - Suspected neonatal isoerythrolysis in two Baird's tapirs (Tapirus bairdii). AB - Two Baird's tapir (Tapirus bairdii) calves born at the Columbus Zoo from the same sire and dam developed hemolytic anemia that was consistent in history and clinical signs with neonatal isoerythrolysis (NI). One calf developed severe, fatal hemolytic anemia after being fed maternal colostrum, and the other developed moderate hemolytic anemia after being fed equine colostrum. No cross reactivity was demonstrated between sire and dam blood samples, and both tapirs possessed serum antibodies reactive against equine blood group Ca and antigens reactive with several equine blood group D antibodies. Electrophoresis demonstrated significant genetic diversity between tapir and equine blood proteins. Agglutination testing demonstrated strong reactivity between a far greater percentage of equine colostrum samples when tested against sire and dam tapir blood (61% and 65%, respectively) than would be expected for equine blood (2%). These data are suggestive of a diagnosis of NI but are not definitive. Further study is required to determine whether NI occurs in tapirs and whether equine colostrum is harmful to tapir calves. PMID- 9365942 TI - Endoscopic ovariohysterectomy in two lions (Panthera leo). AB - Endoscopic techniques were used to ovariohysterectomize two hybrid Asian lions (Panthera leo) in order to reduce the risk of postoperative wound complications associated with standard surgical techniques. One of the lions was aged, overweight, and considered an anesthetic risk. The animals were anesthetized, intubated, catheterized intravenously, and placed in dorsal recumbency with the head lower (Trendelenburg position). Ventilation was assisted mechanically. Following abdominal insufflation, a surgical trocar was placed in the abdominal cavity. Two additional 12-mm surgical trocars were placed under direct visualization using a videoscope. The ovaries and uterus were removed endoscopically, and the abdominal cavity was inspected for hemorrhage under decreased insufflation pressure before closure. The surgery was complicated by obesity, by uterine enlargement from cystic endometrial hyperplasia and endometrial polyps, and by ovarian enlargement and fragility because of bilateral cystic rete ovarii. The procedure and anesthetic recovery were uneventful. Postsurgical recovery time and convalescence lasted less than 3 days, and the animals were reintroduced to an exhibit mate and placed on exhibit within 8 days. The technique is appropriate for use in lions, even those with pathologic reproductive changes, in zoos. PMID- 9365944 TI - Salmonellosis in captive black rhinoceroses (Diceros bicornis). AB - Salmonellosis caused by Salmonella enterica subspecies arizonae (formerly known as Salmonella arizonae) was diagnosed in three of five captive black rhinoceroses (Diceros bicornis) at the Denver Zoological Gardens. Two of the three animals died despite supportive treatment. The other two rhinoceroses remained asymptomatic and were negative for Salmonella spp. after serial fecal cultures. The source for the salmonellosis was never identified. PMID- 9365943 TI - Mortality in captive wild-caught horned puffin chicks (Fratercula corniculata). AB - Sixteen horned puffin (Fratercula corniculata) and six parakeet auklet (Cyclorrhynchus psittacula) chicks of various prefledging ages were caught in Alaska and transported to the North Carolina Zoological Park (USA) in August 1995. Six of the 16 puffin chicks died within a 5-day period beginning 2 days after their arrival into quarantine at the zoo. The birds that died were collected at a young age, weighed 45.4-65.7 g, and had been fed a diet of thawed frozen ocean silversides (Atherinidae) that was not supplemented with vitamins. Clinical signs were nonspecific, and gross necropsies, insecticide toxicology screens, and bacterial cultures were unremarkable. Microscopic examination of tissues from five of the six birds showed myocardial necrosis and degeneration suggestive of vitamin E deficiency and intestinal protozoa resembling Microsporidia. The mortality pattern and histopathologic lesions observed in this case support the use of selective age capture and vitamin supplementation for wild alcid chick collection. PMID- 9365945 TI - Vaccine-induced canine distemper in European mink, Mustela lutreola. AB - This report describes vaccine-induced canine distemper virus (CDV) infection in four European mink (Mustela lutreola) induced by the administration of a multivalent, avian-origin vaccine. Clinical signs consisting of seizures, ataxia, facial twitching, oculonasal discharge, hyperkeratosis of footpads, and anorexia developed 16-20 days postvaccination. Conjunctival smears from one animal were positive for CDV antigen by direct fluorescent antibody testing, confirming the clinical diagnosis. The four mink died 16-26 days postvaccination. Gross and microscopic lesions that were diagnostic for CDV infection included interstitial pneumonia, lymphoid depletion, nonsuppurative encephalitis, and dermatitis. Vaccine-strain virus was isolated from tissues of three animals. Cases of vaccine induced distemper in mustelids using avian-origin vaccine have seldom been reported. PMID- 9365947 TI - Avian paramyxovirus type 1 infection in houbara bustards (Chlamydotis undulata macqueenii): clinical and pathologic findings. AB - Clinical and pathologic findings of avian paramyxovirus type 1 (PMV-1) in 19 houbara bustards (Chlamydotis undulata macqueenii) imported from Pakistan into the United Arab Emirates and one captive-bred bird are reported. Clinical signs included circling, walking backward, ataxia, opisthotonos, torticollis, recumbency, head tilt, head shaking, head tremor, tucking of head under keel, nasal discharge, conjunctivitis, and diarrhea. The length of time imported birds exhibited clinical signs varied from 4 days to 18 mo after importation. Hemagglutinating antibodies against PMV-1 were detected in the sera of all 17 birds from which blood samples were collected, and PMV-1 was isolated from pooled brain, spleen, and lung tissues from two birds with acute clinical signs. There were no distinctive gross lesions at necropsy, and histologic findings were consistent with but not pathognomonic for PMV-1. All houbara bustards managed in a captive breeding and restoration program established by the National Avian Research Center have been vaccinated against PMV-1 since October 1992, and no case of PMV-1 has been reported in this collection since that time. PMID- 9365946 TI - Hypertrophic osteoarthropathy in a blesbok (Damaliscus dorcas phillipsi). AB - A 4.5-yr-old female blesbok (Damaliscus dorcas phillipsi) was radiographed following the appearance of lameness and swelling of the right front fetlock. Radiographic interpretation at that time was osteoarthritis caused by periosteal proliferation of the right metacarpus with periarticular osteophytes surrounding the fetlock. No treatment was initiated. Gradual abdominal enlargement over several months was interpreted as evidence of pregnancy. Six months after the initial lameness complaint, the blesbok suddenly collapsed and was unable to stand. Physical examination revealed a large firm mass occupying most of the abdomen that was found to be inoperable. Following exploratory laporotomy, the blesbok was euthanized. At necropsy, the mass weighed 17 kg. It had probably caused the animal's collapse. Histologically, the bony lesions of the right metacarpus, seen radiographically at the previous examination, were consistent with hypertrophic osteoarthropathy and may have been a sequela of the intra abdominal mass. PMID- 9365948 TI - Tracheal malformation in a bicephalic Honduran milk snake (Lampropeltis hondurensis) and subsequent fatal Salmonella arizonae infection. AB - A bicephalic Honduran milk snake (Lampropeltis hondurensis) with tracheal duplication and malformation and Salmonella arizonae infection is described. There were atypically wide collapsed tracheal rings with necrotizing tracheitis and abundant necrotic epithelial debris and inflammatory cells obstructing the lumen in one of the duplicate tracheae. Salmonella arizonae was cultured from the malformed duplicate trachea and was considered to be the etiologic agent causing necrosis. PMID- 9365949 TI - Suspected dermatophilosis in an adult orangutan (Pongo pygmaeus pygmaeus). AB - An adult female Bornean orangutan (Pongo pygmaeus pygmaeus) had a pruritic, vesicular skin disease, particularly of the extremities, trunk, and face. Over a 2-yr course, symptoms resolved only transiently after corticosteroid treatment. Antibiotic treatment and withdrawal of all corticosteroids resulted in complete recovery of the animal and return to normal activity patterns. On the basis of the dermal histopathologic lesions, Dermatophilus congolensis was suspected as the causative organism, although subsequent cultivation was not attempted because of the stress additional procedures would have caused to the orangutan. PMID- 9365950 TI - Progressive ascending telangiectasia treated with the 585 nm flashlamp-pumped pulsed dye laser. AB - BACKGROUND AND OBJECTIVE: Progressive ascending telangiectasia (PAT) is a distinct entity with telangiectatic superficial vessels on lower extremities as its main clinical feature. A relationship with occult infections and response to antibiotic and antifungal drugs have been described, although not all cases can be successfully managed with these therapies. Our objective was to treat a woman with PAT that had failed to respond to systemic antibiotic and antifungal drugs. STUDY DESIGN/PATIENTS AND METHODS: A 44-year-old woman with PAT was treated with the flashlamp-pumped pulsed dye laser at 585 nm, with fluences varying from 7 to 7.25 J/cm2. RESULTS: A successful outcome was obtained with this treatment approach, with no relevant adverse effects except for mild pigmentary changes. CONCLUSIONS: Although ectatic vessels on lower extremities are often resistant to dye laser therapy, superficial thin capillaries like those featuring PAT can be eliminated with the pulsed dye laser at 585 nm. Transient pigmentary changes occur on treated areas but they are expected to disappear in 6 to 12 months after treatment. Laser treatment should be considered in PAT despite the extension and location of the lesions. PMID- 9365951 TI - Breast cancer diagnosis using N2 laser excited autofluorescence spectroscopy. AB - BACKGROUND AND OBJECTIVE: This article reports results of an in vitro study involving 63 patients for the evaluation of the diagnostic potential of N2 laser excited autofluorescence spectroscopy of human breast tissues. MATERIALS AND METHODS: The N2 laser-excited spectra were recorded from benign (fibroadenomas, 35 patients), cancerous (ductal carcinomas, 28 patients), and normal (the uninvolved areas of the resected cancerous specimens). A stepwise multivariate linear regression (MVLR) analysis was developed to analyze the diagnostic content of the breast tissue fluorescence spectra. RESULTS: Significant changes were observed in the autofluorescence from normal, benign, and cancerous breast tissues, particularly in the spectrally integrated fluorescence intensity. The ratio of mean spectrally integrated intensity from cancerous tissues to that from benign tumor and normal tissues were 3.2 and 2.8, respectively. A discrimination parameter based on spectrally integrated intensity alone provided a sensitivity and specificity of up to 99.6% over the sample size investigated for discrimination of cancerous breast tissues from benign/normal. CONCLUSION: Our results suggest that a straightforward measurement of the total integrated fluorescence intensity can provide excellent discrimination between cancerous and benign/ normal breast tissues. PMID- 9365952 TI - Cisplatinum and interstitial laser therapy for advanced head and neck cancer: a preclinical study. AB - BACKGROUND AND OBJECTIVE: Direct intratumor injection of cisplatinum (CDDP) and laser therapy were tested for improved treatment of squamous cell carcinoma (SCCA). STUDY DESIGN/MATERIALS AND METHODS: Human SCCA tumors were grown as s.c. transplants in nude mice and injected with CDDP (0.4-1.2 mg/gm) in water or in collagen-based gel carrier with epinephrine (epi-gel), followed by interstitial laser therapy (ILT) via 0.6 mm fiberoptics (532 nm/300 J). RESULTS: Tumors injected with CDDP epi-gel exhibited a partial response with 2-4-fold tumor growth delay, compared to aqueous drug or untreated SCCA transplants during 10 week follow-up. Combined drug and laser therapy significantly decreased tumor volume with recurrence in only 25% (2/8) of animals tested, compared to 66% tumor regrowth (10/15) after ILT alone. CONCLUSION: These initial results suggest laser chemotherapy may become an effective treatment for advanced head and neck cancer. PMID- 9365953 TI - CO2 laser treatment of traumatic pulpal exposures in dogs. AB - BACKGROUND AND OBJECTIVE: Successful non-devitalizing treatment of localized pulpal lesions in mature teeth is not ensured using conventional endodontic techniques. The objective of this study was to evaluate CO2 laser surgical treatment of pulpal exposures in canine patients. STUDY DESIGN/MATERIALS AND METHODS: 17 permanent teeth with pulpal exposures of < or = 48 h duration received localized laser pulp surgery. Laser Parameters: pulse duration: 0.01 s, pulse interval: 1.0 s, spot size: 0.004 cm2, fluence: 276 J/cm2. Exposures were dressed with CaOH and Glass ionomer. Clinical and radiographic evaluations were performed by one blinded clinician 24 and 52 weeks after treatment. RESULTS: 15/17 laser-treated teeth assessed over > or = 1 year post-treatment remained clinically and radiographically healthy. CONCLUSION: These results demonstrate the feasibility of using the CO2 laser for localized pulp surgery. Further studies must optimize laser parameters and identify the range of clinical pathologies which can be treated using this modality. PMID- 9365954 TI - Morphologic changes in collagen fibers after 830 nm diode laser welding. AB - BACKGROUND AND OBJECTIVE: The mechanism of laser tissue welding is elusive, but collagen transitions are somehow involved. Collagen fiber modifications observed after 830 nm diode laser welding are presented in this study. STUDY DESIGN/MATERIALS AND METHODS: A 830 nm diode laser assisted longitudinal aortorrhaphy was performed on 37 Wistar rats, with shots of 0.5 W in power, 8 sec in duration and 250 W/cm2 in irradiance. Energy utilized ranged from 400-550 J/ mm2 for 1 cm-length of anastomosis. After laser welding, histological modifications in collagen fibers were observed through optic, scanning electron, and electron microscopic examination. RESULTS: After laser welding, collagen fibers lost a proportion of birefringence. Under electron microscope, the different changes in collagen fibers were visualized being either fused, "roped," swollen, or dissolved, surrounded by normal ones situated in the same zone. CONCLUSION: These data suggest that diode laser heating denatured part of the collagenic fibers, and that these morphologic changes play an important role in laser welding. PMID- 9365955 TI - Intracranial pressure waves generated by high-energy short laser pulses can cause morphological damage in remote areas: comparison of the effects of 2.1-micron Ho:YAG and 1.06-micron Nd:YAG laser irradiations in the rat brain. AB - BACKGROUND AND OBJECTIVE: Histological effects of 2.1-micron Ho:YAG and 1.06 micron Nd:YAG laser pulses were compared in the rat brain, with special regard to areas remote from the irradiated site. STUDY DESIGN/MATERIALS AND METHODS: Laser pulses were delivered through a 0.6-mm glass fiber, the tip of which was either introduced into the caudate nucleus (application mode I), or held at a 2-mm distance above the exposed intact dura. In the latter case, the space between the dura and the fiber tip was filled either with physiological saline (application mode II) or with air (application mode III). RESULTS: In application modes I and II, but not in application mode III, Ho:YAG laser pulses of 1.5 J and 200 microseconds, but not Nd:YAG laser pulses with the same parameters, immediately caused morphological damage to a considerable number of neurons and axons randomly distributed among apparently normal ones in certain areas remote from the irradiated site. A decrease in the energy and an increase in the length of the pulses lowered the incidence of the remote morphological damage. CONCLUSION: This novel finding may impose limits on the application of Ho:YAG lasers in human endoscopic neurosurgery. PMID- 9365956 TI - Low-energy diode laser irradiation reduced plasminogen activator activity in human periodontal ligament cells. AB - BACKGROUND AND OBJECTIVE: The plasminogen activator (PA)-plasmin proteolytic system is implicated in the degradation of the extracellular matrix in inflammation. Since human periodontal ligament (PDL) cells produced high PA activity in response to mechanical stress, excessive mechanical stress to PDL cells such as occlusal trauma may induce collagen breakdown through activation of the PA-plasmin system. As low-energy laser irradiation has anti-inflammatory effects, we examined the effects of low-energy laser irradiation on the PA plasmin system in stretched PDL cells in vitro. STUDY DESIGN/MATERIALS AND METHODS: Human PDL cells obtained from healthy premolars were mechanically stretched and Ga-Al-As low-energy laser was irradiated (830 nm, 3.95 to 7.90 J/cm2) to the stretched cells. RESULTS: PDL cells showed a marked elevation in PA activity in response to stretching, which was significantly inhibited by a laser irradiation in a dose-dependent manner (55-86%, p < 0.001). This effect could involve transcriptional events of tissue type (t) PA gene. CONCLUSION: These results suggests that laser irradiation may reduce collagen breakdown around the PDL associated with traumatic occlusion. PMID- 9365957 TI - Imaging temperature changes in an interventional 0.5 T magnet: in-vitro results. AB - BACKGROUND AND OBJECTIVE: To evaluate the ability of monitoring laser induced temperature changes in an open, interventional 0.5 T magnet, adopting fast T1 weighted sequences. MATERIALS AND METHODS: A fast gradient echo- (FGRE) and a fast spoiled gradient echo-sequence (FSPGR), both enabling an image update every 2.5 s, were investigated for their ability to visualize laser tissue effects at 5 Watt. Laser induced temperature was fluorooptically measured and correlated with signal intensity (SI) changes depicted by magnetic resonance imaging (MRI). MRI lesions were compared with macroscopic findings. RESULTS: SI changes on FGRE images appeared as early as 15 s following the onset of laser application and were significantly more pronounced than those seen on FSPGR images (p < .0001). A correlation of r = 0.94 (FGRE) and r = 0.92 (FSPGR) between temperature and SI loss was established. Owing to a steeper slope, the FGRE sequence was considered more sensitive to temperature changes. The areas of macroscopic tissue change correlated with those of SI loss, but lesion size was generally underestimated by MRI. CONCLUSION: Laser monitoring is possible with rapid image updates in a midfield (0.5 T) interventional MRI environment using fast gradient echo sequence designs. PMID- 9365958 TI - ArF excimer laser irradiation of human dentin. AB - BACKGROUND AND OBJECTIVE: The use of excimer lasers for treatment of dental hard tissues has considerable potential because the combined characteristics of low wavelength and short pulse result in limited heat diffusion and, therefore, tissue ablation without the problems of collateral damage. To date, there are relatively few published studies concerning the effects of excimer laser irradiation on dental hard tissues. Thus the present study was conducted to examine the morphological changes in tooth dentin subsequent to ArF excimer laser irradiation. STUDY DESIGN/MATERIALS AND METHODS: The morphologic changes induced in normal, nondiseased human dentin following irradiation by an ArF excimer laser at fluences ranging from 1 to 4 J/cm2 and the number of laser pulses ranging from 50 to 1,000 were evaluated by scanning electron microscopy. RESULTS: Two modes of ablation, photochemical at low fluences and thermal at high fluences, were observed. A fluence of 1 J/ cm2 when combined with 50 or 100 pulses produced a uniform ablation of the dentin surface without signs of tissue melting. At fluences > 1.5 J/cm2, the thermal mode of ablation was more efficient at removing intertubular dentin than peritubular dentin. Further, when compared to the lower fluences, the higher settings produced a rougher ablation crater surface. Additionally, the higher fluences produced surface melting with each pulse and sealing of exposed dentinal tubules after irradiation with 100-300 laser pulses. CONCLUSIONS: The photochemical and thermal mechanisms of tooth dentin ablation were identified based on significant differences in tissue morphology following laser irradiation. The rates of tissue ablation and the observed morphologic changes indicate that the ArF excimer laser could be useful for caries removal and sealing of exposed dentinal tubules. PMID- 9365959 TI - Laser's effect on bone and cartilage change induced by joint immobilization: an experiment with animal model. AB - OBJECTIVE: Influence of low-level (810 nm, Ga-Al-As semiconductor) laser on bone and cartilage during joint immobilization was examined with rats' knee model. MATERIALS AND METHODS: The hind limbs of 42 young Wistar rats were operated on in order to immobilize the knee joint. One week after operation they were assigned to three groups; irradiance 3.9 W/cm2, 5.8 W/cm2, and sham treatment. After 6 times of treatment for another 2 weeks both hind legs were prepared for 1) indentation of the articular surface of the knee (stiffness and loss tangent), and for 2) dual energy X-ray absorptiometry (bone mineral density) of the focused regions. RESULTS AND CONCLUSIONS: The indentation test revealed preservation of articular cartilage stiffness with 3.9 and 5.8 W/cm2 therapy. Soft laser treatment has a possibility for prevention of biomechanical changes by immobilization. PMID- 9365960 TI - Nonmonotonic behavior of the dose dependence of the radiation effect on cells in vitro exposed to pulsed laser radiation at lambda = 820 nm. AB - BACKGROUND AND OBJECTIVE: In recent years, clinical low-intensity laser therapy practice has used pulsed radiation, mainly from semiconductor lasers. Experimental works devoted to the study of relationships between biological and clinical effects and parameters of pulsed radiation are practically absent. STUDY DESIGN/MATERIALS AND METHODS: The radiation source was a laser diode emitting at 820 nm (292 and 700 Hz, duty factor 80%; doses from 7 J/m2 to 5 x 10(5) J/m2; intensities 4, 12, 51, 152, 633, and 1,900 W/m2; irradiation time from 1 to 30 s). Four biological models were used: nucleated cells of murine spleen (splenocytes) and bone marrow (karyocytes), murine blood, and HeLa cells cultivated in vitro. The intensity of luminol-amplified chemiluminescence (in case of murine models) and the adhesion of HeLa cell membranes were measured as a function of the irradiation dose. RESULTS: Within the wide exposure dose range used we obtained seven maxima in the dose vs. biological effect curves: at fluences near 20, 1 x 10(2), 3 x 10(2), 8 x 10(2), 3 x 10(3), 1 x 10(4), and 3 x 10(4) J/m2. The peaks coincided for all four models. CONCLUSION: The dose curves obtained with different cellular systems are of the same type and are characterized by seven peaks in the dose interval studied (7 J/m2 to 5 x 10(5) J/m2). PMID- 9365961 TI - Changes in calcium transport in mammalian sperm mitochondria and plasma membranes caused by 780 nm irradiation. AB - BACKGROUND AND OBJECTIVE: Regulation of intracellular Ca2+ concentrations are very important in control of sperm motility and acrosome reaction. It was shown previously that low-power lasers in the visible and near-infrared range alter Ca2+ uptake by sperm cells. In the present work the effect of a 780 nm diode laser on Ca2+ uptake by sperm mitochondria and isolated plasma membrane vesicles is investigated. STUDY DESIGN/MATERIALS AND METHODS: Digitonin-treated spermatozoa and plasma membrane vesicles were irradiated with a 780-nm diode laser at various powers and energy doses, and Ca2+ uptake was measured by the filtration method. RESULTS: It was found that 780-nm irradiation inhibits Ca2+ uptake by the mitochondria but stimulates Ca2+ binding by sperm plasma membrane vesicles. The effect of light on Ca2+ uptake by plasma membrane vesicles in the absence of ATP was much larger than that measured in the presence of ATP. Addition of Ca2+ ionophore decreased the Ca2+ uptake by the irradiated membranes in the presence of ATP but enhanced it significantly in the absence of ATP. CONCLUSION: 780 nm light inhibits Ca2+ uptake by sperm mitochondria and enhances Ca2+ binding to sperm plasma membranes. PMID- 9365962 TI - Effectiveness of the 585nm flashlamp-pulsed tunable dye laser (PTDL) for treatment of plantar verrucae. AB - BACKGROUND AND OBJECTIVE: The objective of this study was to establish the 585 nm flashlamp-pulsed tunable dye laser (PTDL) as a potentially effective modality in the treatment of plantar verrucae. Furthermore, this study attempted to identify if certain regions of the plantar surface yielded a different clearance rate in comparison to others. STUDY DESIGN/MATERIALS AND METHODS: Thirty-three patients were recruited for this case series study, representing a total of 97 plantar warts. Patients were treated using the flashlamp-PTDL with a pulse duration of 450 microseconds, a spot diameter of 5.0 mm, and energy fluences ranging between 8.1 and 8.4 J/cm2. Patients were followed-up an average of 2-24 weeks assessing for recurrence of verrucae. RESULTS: Each patient exhibited one to eight plantar lesions. Of the 97 verrucae treated by the flashlamp-PTDL, 68 (70.1%) resolved with 100% clearance of the lesion. The overall mean clearance of the 97 lesions was 95.1 +/- 16.5%. Of the 97 lesions treated to maximal clearance, 14 lesions recurred after a mean follow-up period of 9.0 weeks. CONCLUSION: Results of this study have established the 585 nm flashlamp-pulsed tunable dye laser as a potentially effective modality treatment of plantar warts. Furthermore, it was determined that there was no significant difference in the clearance rate of warts located at a given plantar site when compared to the clearance rates of the other plantar sites (F3/44 = 0.58, P = 0.634). PMID- 9365963 TI - [Detection and characterization of free radicals, radical scavenging activity, and lipid peroxides in cerebral ischemia-reperfusion injury by electron spin resonance and chemiluminescence high-performance liquid chromatography]. AB - During the ischemia-reperfusion period, the hypoxanthine-xanthine oxidase system simultaneously generates superoxide (O2-). O2- has an extremely short half-life, as it rapidly undergoes Fenton-type reactions in the presence of iron and yields highly cytotoxic hydroxyl radicals (.OH). Oxygen-derived free radicals are induced as a contributing cause of cellular injury in several neurological disorders, including cerebral infarction and aging. Cerebral injury by ischemia reperfusion following middle cerebral artery occlusion could be useful experimental model for studying cerebral injury induced by free radicals. Thiobarbituric acid reactants generally indicate lipid peroxidation associated with cellular damage caused by free radicals. Phosphatidylethanolamine hydroperoxide (PEOOH) is the primary peroxidative product of phosphatidylethanolamine, which is the most important functional lipid in the membrane. Plasma PEOOH levels appear to be a reliable indicator of cerebral damage caused by ischemia-reperfusion and other oxidative stress. Recently, an electron spin resonance (ESR) spectrometer was used in the detection of free radicals, in vivo and in vitro using 5,5'-dimethyl-1-pyrroline-N-oxide (DMPO) as the radical-trapping reagent. Moreover, there are reports the electron spin resonance-computed tomography (ESR-CT) images of the cephalic region of rats for locating regions of pathological change are related to free radicals in the brain. PMID- 9365964 TI - [Neuronal growth-associated proteins in neural plasticity and brain aging]. AB - This review summarizes current issues on neuronal structural plasticity and its molecular marker genes in the aged brain. Neuronal growth-associated proteins (nGAPs) are introduced as potential markers of neuronal structural plasticity in the brain. The expression of genes encoding nGAPs such as GAP-43, SCG10 and stathmin is increased following striatal and hippocampal neuronal deafferentation lesions in the adult rat brain. In aged brains, the magnitude of neuronal plasticity is reduced and nGAP gene induction is limited at least in part, while the kinetics of the response remains unchanged in comparison to young brains. These results suggest that nGAPs serve as molecular markers of neuronal structural plasticity in the aging brain and that neuronal plasticity decreases, at least in certain neuronal circuits, during aging. The expression of genes encoding SCG10, stathmin and GAP-43 is also altered in age-related neurodegenerative conditions such as Alzheimer's disease in humans. Thus, studies of nGAPs are important for the elucidation of the mechanisms of the reduction of neuronal structural plasticity in aged brains. PMID- 9365965 TI - [Histaminergic neuron system and neural plasticity]. AB - The histaminergic neuron system is located in the posterior hypothalamus as a tuberomammillary nucleus (TM) and sends nerve fibers with varicosities to almost all regions of the brain from the olfactory bulb to the spinal cord, suggesting that this neuron system is involved in the control of the activities of the whole brain. We examined the effects of pharmacological manipulations of the histaminergic neuron system on various kinds of invasive stimuli, such as methamphetamine behavioral sensitization (reverse tolerance), neuronal cell death caused by brain ischemia and electroconvulsive shock. Nerve degeneration caused by chemical and physical denervation caused an increase in H3 receptors in the postsynaptic sites. It seems likely that histamine functions in a direction to protect against various stimuli to maintain homeostasis, which is in good agreement with the morphological characteristics described above. PMID- 9365966 TI - Glutamate in opioid dependence. AB - The present review will concentrate on a discussion of recent investigations which implicate a critical linkage of three facets of the central nervous system mediation of opioid dependence, as evidenced by expression of acutely precipitated withdrawal events. These are the kappa-opioid receptor subtype, the glutamatergic neuronal system and a specific brain locus, the locus coeruleus. The impetus for this line of investigation derives from a recognition that opioid analgesics, such as butorphanol (Stadol), exhibit a markedly different profile of activity at opioid receptors than does morphine yet have abuse liability and cause dependence readily. Emphasis will be placed on demonstration of a rodent model in which butorphanol administration induces dependence through a unique (in comparison with morphine) activation of the kappa-opioid receptor. The use of in vivo microdialysis techniques clearly identifies, in this model, that acutely precipitated withdrawal from dependence on butorphanol results in focal increases in extracellular levels of glutamate within the locus coeruleus, and that the withdrawal syndrome can be mimicked by intracerebroventricular administration of exogenous glutamate, acting through the N-methyl-D-aspartate glutamate receptor subtype. The data confirm the participation of glutamate as a general phenomenon in opioid dependence, identify the locus coeruleus as a primary site for glutamatergic mediation of dependence, and suggest novel aspects to the neuropharmacology of opioid dependence with respect to the role of the kappa opioid receptor. PMID- 9365967 TI - Laryngeal damage from tracheal intubation. PMID- 9365968 TI - Haemodynamic responses to sevoflurane compared with halothane during inhalational induction in children. AB - We studied the haemodynamic changes during induction of anaesthesia in 50 ASA I and II children (1-12 yrs) undergoing minor elective surgery. The patients were randomly divided into two groups to receive either halothane (n = 25) or sevoflurane (n = 25) in a mixture of O2 and N2O (40:60) for mask induction of anaesthesia. Induction of anaesthesia was performed with an overpressure technique by administering rapid increases of gas concentrations, in increments of 1% up to 7% for sevoflurane and of 0.5% up to 3% for halothane. Induction was smooth and rapid in both groups but characterized by increases in heart rate and systolic blood pressure up to 20% especially in the sevoflurane group (P < 0.05); these increases in the latter group were significant compared with baseline and the halothane group (P < 0.05). No serious complications were observed. The authors conclude that more children experienced heart rate and blood pressure increases during the early stage of inhalational induction with sevoflurane compared with halothane. PMID- 9365969 TI - The analgesic efficacy of an injectable prodrug of acetaminophen in children after orthopaedic surgery. AB - The analgesic efficacy and safety of propacetamol, an injectable prodrug of acetaminophen, (paracetamol) were studied in 87 children (36 boys, 51 girls; age 6-13; mean age 9.5 years) immediately after limb surgery. Using a double-blind, randomized, parallel group design, the effects of a single IV infusion of 30 mg.kg-1 propacetamol (i.e. 15 mg.kg-1 acetaminophen) were compared with a single injection of placebo (PL). Efficacy was assessed on pain scores rated on a four point verbal scale, a five-point visual scale (faces) and on a four-point relief verbal scale before administration (T0) and 0.25, 0.5, 1, 2, 3, 4, 5, 6 h after administration. At the end the global efficacy was rated by the physician on a five-point verbal scale. Propacetamol was statistically superior to placebo on all assessment criteria. Seven side-effects were recorded: five in the propacetamol group and two in the placebo group. 30 mg.kg-1 propacetamol provided a significantly greater analgesic effect than placebo in children after orthopaedic surgery. PMID- 9365970 TI - Rectal paracetamol dosing regimens: determination by computer simulation. AB - A pharmacokinetic dynamic simulation model was used to predict rectal paracetamol dosing schedules which would maintain steady state plasma concentrations of 10-20 mg.l-1. These plasma concentrations of paracetamol are known to reduce fever. The conventional dosing schedule of 15 mg.kg-1 four hourly was unsatisfactory. Steady state concentrations of 8-12 mg.l-1 were only reached after 16 h. A loading dose of 50 mg.kg-1 followed by 30 mg.kg-1 six hourly achieved plasma concentrations of 9-18 mg.l-1. Paracetamol is a mild analgesic. A higher plasma paracetamol concentration of 25 mg.l-1 is known to give satisfactory analgesia to 60% of children after tonsillectomy. This concentration can be reached after a loading dose of 70 mg.kg-1 and a maintenance dose of 50 mg.kg-1 8 hourly. Doses above 150 mg.kg-1.day-1 have been reported to cause reversible liver toxicity after 2-8 days and should not be sustained. PMID- 9365971 TI - Plasma concentrations after rectal administration of acetaminophen in preterm neonates. AB - Acetaminophen is frequently administered to infants and children for its antipyretic and analgesic properties. Oral administration is the route of choice in daily practice. In some circumstances this is impractical. Rectal administration of acetaminophen is an alternative route. This study measures plasma concentrations following rectal administration of acetaminophen 20 mg.kg-1 (10% Infants' Tylenol Drops, McNeil Consumer Product Co., diluted with an equal volume of sterile water) in five preterm neonates. Serial arterial blood samples were obtained at 0, 15, 30, 60, 120, and 240 min. Pharmacokinetic parameters were (mean +/- SD): Cmax (maximum plasma concentration) of 8.38 +/- 3.92 micrograms.ml 1 and Tmax (time to reach maximum plasma concentration) of 78.0 +/- 40.2 min. Our results show that 20 mg.kg-1 of acetaminophen rectally results in low plasma levels in preterm neonates. PMID- 9365972 TI - Tracheal administration of atropine in children--effect on heart rate. AB - Forty-one ASA I patients, aged 2-6 years, anaesthetized for elective ear, nose and throat surgery, were studied in a double blind and randomized fashion in order to examine the effect of tracheally administered atropine 0.02 mg.kg-1 or saline 0.9% on heart rate. In patients receiving atropine heart rate increased 8.8 beats.min-1 (8.7%) and 16.2 beats.min-1 (16.0%) after 3 and 5 min respectively. No increase in heart rate was seen in the saline group. Because of the late onset of action and only moderate increase in heart rate it is concluded that tracheal administration of atropine 0.02 mg.kg-1 to children is insufficient in emergency situations. PMID- 9365973 TI - Maxillary hypoplasia with unsuspected choanal atresia. AB - Maxillary hypoplasia can pose considerable anaesthetic problems in securing the airway. The presence of concomitant, unsuspected choanal stenosis complicated the anaesthetic management of a 20-day-old baby for tarsorrhaphy. PMID- 9365974 TI - Bilateral continuous paravertebral block used for postoperative analgesia in an infant having bilateral thoracotomy. AB - We describe the successful postoperative pain management in an 11-month-old infant who underwent bilateral thoracotomy, using continuous infusions of bupivacaine into two directly placed paravertebral catheters. Haemodynamic parameters and pain scores were measured 1-2 h for 60 h while the infusions were continued and, intermittently, blood samples were taken for subsequent measurement of serum bupivacaine concentrations. The technique provided effective pain relief and the infant required no other analgesia postoperatively. There were no adverse haemodynamic consequences or complications relating to either catheter placement or drug infusions. Serum concentrations of bupivacaine remained below toxic levels throughout the study period, though accumulation did occur. PMID- 9365975 TI - Hangman's fracture in a paediatric patient: considerations for anaesthesia. AB - Cervical spine injuries are quite uncommon in children. When occurring, these lesions are of particular concern for the anaesthesiologist. This case refers to an hangman's fracture diagnosed in a four-month-old female infant, which probably occurred at birth. We describe the anaesthetic management adopted in this infant undergoing diagnostic procedures and conservative treatment. The problems related to airway control and the anaesthetic management utilized to diagnose and treat this unusual paediatric pathology are highlighted. PMID- 9365976 TI - Costello syndrome. PMID- 9365977 TI - Convulsions and sevoflurane. PMID- 9365979 TI - Paediatric pain management--the next step? PMID- 9365978 TI - Use of Ropivacaine in postoperative infusions. PMID- 9365980 TI - Paediatric intensive care: a developing specialty. PMID- 9365981 TI - Intra-aortic balloon pumping in young children. PMID- 9365982 TI - Report on the 1997 Johns Hopkins Protein Folding meeting. PMID- 9365983 TI - Modeling the paramyxovirus hemagglutinin-neuraminidase protein. AB - The paramyxovirus hemagglutinin-neuraminidase (HN) protein exhibits neuraminidase activity and has an active site functionally similar to that in influenza neuraminidases. Earlier work identified conserved amino acids among HN sequences and proposed similarity between HN and influenza neuraminidase sequences. In this work we identify the three-dimensional fold and develop a more detailed model for the HN protein, in the process we examine a variety of protein structure prediction methods. We use the known structures of viral and bacterial neuraminidases as controls in testing the success of protein structure prediction and modeling methods, including knowledge-based threading, discrete three dimensional environmental profiles, hidden Markov models, neural network secondary structure prediction, pattern matching, and hydropathy plots. The results from threading show that the HN protein sequence has a 6 beta-sheet propellor fold and enable us to assign the locations of the individual beta strands. The three-dimensional environmental profile and hidden Markov model methods were not successful in this work. The model developed in this work helps to understand better the biological function of the HN protein and design inhibitors of the enzyme and serves as an assessment of some protein structure prediction methods, especially after the x-ray crystallographic solution of its structure. PMID- 9365984 TI - Local interactions and the optimization of protein folding. AB - The role of local interactions in protein folding has recently been the subject of some controversy. Here we investigate an extension of Zwanzig's simple and general model of folding in which local and nonlocal interactions are represented by functions of single and multiple conformational degrees of freedom, respectively. The kinetics and thermodynamics of folding are studied for a series of energy functions in which the energy of the native structure is fixed, but the relative contributions of local and nonlocal interactions to this energy are varied over a broad range. For funnel shaped energy landscapes, we find that 1) the rate of folding increases, but the stability of the folded state decreases, as the contribution of local interactions to the energy of the native structure increases, and 2) the amount of native structure in the unfolded state and the transition state vary considerably with the local interaction strength. Simple exponential kinetics and a well-defined free energy barrier separating folded and unfolded states are observed when nonlocal interactions make an appreciable contribution to the energy of the native structure; in such cases a transition state theory type approximation yields reasonably accurate estimates of the folding rate. Bumps in the folding funnel near the native state, which could result from desolvation effects, side chain freezing, or the breaking of nonnative contacts, significantly alter the dependence of the folding rate on the local interaction strength: the rate of folding decreases when the local interaction strength is increased beyond a certain point. A survey of the distribution of strong contacts in the protein structure database suggests that evolutionary optimization has involved both kinetics and thermodynamics: strong contacts are enriched at both very short and very long sequence separations. PMID- 9365985 TI - Short-range conformational energies, secondary structure propensities, and recognition of correct sequence-structure matches. AB - A statistical analysis of known structures is made for an assessment of the utility of short-range energy considerations. For each type of amino acid, the potentials governing (1) the torsions and bond angle changes of virtual C alpha-C alpha bonds and (2) the coupling between torsion and bond angle changes are derived. These contribute approximately -2 RT per residue to the stability of native proteins, approximately half of which is due to coupling effects. The torsional potentials for the alpha-helical states of different residues are verified to be strongly correlated with the free-energy change measurements made upon single-site mutations at solvent-exposed regions. Likewise, a satisfactory correlation is shown between the beta-sheet potentials of different amino acids and the scales from free-energy measurements, despite the role of tertiary context in stabilizing beta-sheets. Furthermore, there is excellent agreement between our residue-specific potentials for alpha-helical state and other thermodynamic based scales. Threading experiments performed by using an inverse folding protocol show that 50 of 62 test structures correctly recognize their native sequence on the basis of short-range potentials. The performance is improved to 55, upon simultaneous consideration of short-range potentials and the nonbonded interaction potentials between sequentially distant residues. Interactions between near residues along the primary structure, i.e., the local or short-range interactions, are known to be insufficient, alone, for understanding the tertiary structural preferences of proteins alone. Yet, knowledge of short-range conformational potentials permits rationalizing the secondary structure propensities and aids in the discrimination between correct and incorrect tertiary folds. PMID- 9365986 TI - Insights into thermal resistance of proteins from the intrinsic stability of their alpha-helices. AB - To investigate the role of alpha helices in protein thermostability, we compared energy characteristics of alpha helices from thermophilic and mesophilic proteins belonging to four protein families of known three-dimensional structure, for at least one member of each family. The changes in intrinsic free energy of alpha helix formation were estimated using the statistical mechanical theory for describing helix/coil transitions in peptide helices [Munoz, V., Serrano, L. Nature Struc. Biol. 1:399-409, 1994; Munoz, V., Serrano, L. J. Mol. Biol. 245:275 296, 1995; Munoz, V., Serrano, L. J. Mol. Biol. 245:297-308, 1995]. Based on known sequences of mesophilic and thermophilic RecA proteins we found that (1) a high stability of alpha helices is necessary but is not a sufficient condition for thermostability of RecA proteins, (2) the total helix stability, rather than that of individual helices, is the factor determining protein thermostability, and (3) two facets of intrahelical interactions, the intrinsic helical propensities of amino acids and the side chain-side chain interactions, are the main contributors to protein thermostability. Similar analysis applied to families of L-lactate dehydrogenases, seryl-tRNA synthetases, and aspartate amino transferases led us to conclude that an enhanced total stability of alpha helices is a general feature of many thermophilic proteins. The magnitude of the observed decrease in intrinsic free energy on alpha-helix formation of several thermoresistant proteins was found to be sufficient to explain the experimentally determined increase of their thermostability. Free energies of intrahelical interactions of different RecA proteins calculated at three temperatures that are thought to be close to its normal environmental conditions were found to be approximately equal. This indicates that certain flexibility of RecA protein structure is an essential factor for protein function. All RecA proteins analyzed fell into three temperature-dependent classes of similar alpha-helix stability (delta G(int) = 45.0 +/- 2.0 kcal/mol). These classes were consistent with the natural origin of the proteins. Based on the sequences of protein alpha helices with optimized arrangement of stabilizing interactions, a natural reserve of RecA protein thermoresistance was estimated to be sufficient for conformational stability of the protein at nearly 200 degrees C. PMID- 9365987 TI - Solution structure of maurotoxin, a scorpion toxin from Scorpio maurus, with high affinity for voltage-gated potassium channels. AB - Maurotoxin (MTX), purified from the scorpionid Scorpio maurus is a potent ligand for potassium channels. It shows a broad specificity as being active on Kv1.1 (Kd = 37 nM), Kv1.2 (Kd = 0.8 nM), Kv1.3 (Kd = 150 nM) voltage-gated potassium channels, as well as on small-conductance calcium-activated potassium channels. It has a unique disulfide pairing among the scorpion toxins family. The solution structure of MTX has been determined by 2D-NMR techniques, which led to the full description of its 3D conformation: a bended helix from residues 6 to 16 connected by a loop to a two-stranded antiparallel beta sheet (residues 23 to 26 and 28 to 31). The interaction of MTX with the pore region of the Kv1.2 potassium channel has been modeled according to their charge anisotropy. The structure of MTX is similar to other short scorpion toxins despite its peculiar disulfide pairing. Its interaction with the Kv1.2 channel involves a dipole moment, which guides and orients the toxin onto the pore, toward the binding site, and which thus is responsible for the specificity. PMID- 9365988 TI - Glucoamylase structural, functional, and evolutionary relationships. AB - To correlate structural features with glucoamylase properties, a structure-based multisequence alignment was constructed using information from catalytic and starch-binding domain models. The catalytic domain is composed of three hydrophobic folding units, the most labile and least hydrophobic of them being missing in the most stable glucoamylase. The role of O-glycosylation in stabilizing the most hydrophobic folding unit, the only one where thermostabilizing mutations with unchanged activity have been made, is described. Differences in both length and composition of interhelical loops are correlated with stability and selectivity characteristics. Two new glucoamylase subfamilies are defined by using homology criteria. Protein parsimony analysis suggests an ancient bacterial origin for the glucoamylase gene. Increases in length of the belt surrounding the active site, degree of O-glycosylation, and length of the linker probably correspond to evolutionary steps that increase stability and secretion levels of Aspergillus-related glucoamylases. PMID- 9365989 TI - Paramagnetic relaxation as a tool for solution structure determination: Clostridium pasteurianum ferredoxin as an example. AB - The possibility of using the relaxation properties of nuclei for solution structure determination of paramagnetic metalloproteins is critically evaluated. First of all, it is theoretically and experimentally demonstrated that magnetization recovery in nonselective inversion recovery experiments can be approximated to an exponential in both diamagnetic and paramagnetic systems. This permits the estimate of the contribution of paramagnetic relaxation when dominant or sizable. Then, it is shown that the averaging of paramagnetic relaxation rates due to cross relaxation is often tolerably small with respect to the use of paramagnetic relaxation rates as constraints for structural determination. Finally, a protocol is proposed to use such paramagnetic relaxation rates, which depend on the sixth power of the metal to resonating nucleus distance, as constraints for solution structure determination of proteins. As an example, the available solution structure of the oxidized ferredoxin from Clostridium pasteurianum has been significantly improved in resolution especially in the proximity of the metal ions by using 69 new constraints based on paramagnetic relaxation. PMID- 9365990 TI - Solution structure of TsKapa, a charybdotoxin-like scorpion toxin from Tityus serrulatus with high affinity for apamin-sensitive Ca(2+)-activated K+ channels. AB - TsKapa (TsK), purified from the Buthidae Tityus serrulatus is a very high potent ligand for small-conductance apamin-sensitive calcium-activated potassium channels (SK). It is able to efficiently compete with apamin for binding on this channel (K0.5 = 0.3 nM) [Legros, C. et al., FEBS Lett. 390:81-84, 1996]. The solution structure of TsK has been determined by 2D-NMR techniques, which led to the full description of its 3D conformation: a short alpha helix from residues 14 to 20 and a three-stranded antiparallel beta sheet (residues 2-3, 27-29, and 32 34). The interaction of TsK with the SK potassium channel has been modeled according to the charge anisotropy of the ligand. The resulting dipole moment orientates TsK so that it presents toward the receptor, a surface, mainly basic, encompassing residues K18 and K19 on one side and R9 and Y8 on the other. Despite its three-dimensional structure that is related with scorpion toxins active on voltage-gated potassium channels such as charybdotoxin, the pharmacological activity and specificity of TsK is related with shorter scorpion toxins (i.e., possessing an only two-stranded beta sheet) such as scyllatoxin (also named leiurotoxin I) or P05. PMID- 9365991 TI - Non-randomness in side-chain packing: the distribution of interplanar angles. AB - We analyze the distributions of interplanar angles between interacting side chains with well-defined planar regions, to see whether these distributions correspond to random packing or alternatively show orientational preferences. We use a non-homologous set of 79 high-resolution protein chain structures to show that the observed distributions are significantly different from the sinusoidal one expected for random packing. Overall, we see a relative excess of small angles and a paucity of large interplanar angles; the difference between the expected and observed distributions can be described as a shift of 5% of the interplanar angles from large (> or = 60 degrees) to small (< 30 degrees) values. By grouping the residue pairs into categories based on chemical similarity, we find that some categories have very non-sinusoidal interplanar angle distributions, whereas other categories have distributions that are close to sinusoidal. For a few categories, observed deviations from a sinusoidal distribution can be explained by the electrostatic anisotropy of the isolated pair potential energy. In other cases, the observed distributions reflect the longer range effects of different possible interaction geometries. In particular, geometries that disrupt external hydrogen bonding are disfavored. PMID- 9365992 TI - Extreme heat- and pressure-resistant 7-kDa protein P2 from the archaeon Sulfolobus solfataricus is dramatically destabilized by a single-point amino acid substitution. AB - This study reports the characterization of the recombinant 7-kDa protein P2 from Sulfolobus solfataricus and the mutants F31A and F31Y with respect to temperature and pressure stability. As observed in the NMR, FTIR, and CD spectra, wild-type protein and mutants showed substantially similar structures under ambient conditions. However, midpoint transition temperatures of the denaturation process were 361, 334, and 347 K for wild type, F31A, and F31Y mutants, respectively: thus, alanine substitution of phenylalanine destabilized the protein by as much as 27 K. Midpoint transition pressures for wild type and F31Y mutant could not be accurately determined because they lay either beyond (wild type) or close to (F31Y) 14 kbar, a pressure at which water undergoes a phase transition. However, a midpoint transition pressure of 4 kbar could be determined for the F31A mutant, implying a shift in transition of at least 10 kbar. The pressure-induced denaturation was fully reversible; in contrast, thermal denaturation of wild type and mutants was only partially reversible. To our knowledge, both the pressure resistance of protein P2 and the dramatic pressure and temperature destabilization of the F31A mutant are unprecedented. These properties may be largely accounted for by the role of an aromatic cluster where Phe31 is found at the core, because interactions among aromatics are believed to be almost pressure insensitive; furthermore, the alanine substitution of phenylalanine should create a cavity with increased compressibility and flexibility, which also involves an impaired pressure and temperature resistance. PMID- 9365993 TI - Prediction of the secondary structure of the nicotinic acetylcholine receptor nontransmembrane regions. AB - A consensus prediction for the secondary structure of the muscle nicotinic acetylcholine receptor (alpha, beta, gamma, and delta subunits) extracellular regions is presented. This protein is a member of the ligand-gated ion channel superfamily, which also encompasses the 5HT3, GABAA, and glycine receptors. The strategy used here is based on the application of six different prediction methods to an alignment of 118 sequences of this superfamily. A consensus prediction was finally produced for each of the four different subunits of the muscle nicotinic receptor nonmembrane regions. The predicted percentages, with respect to the total receptor length, and averaged for the four subunits are as follows: alpha-helix 29.7%, beta-sheet 24.9%, and turn + coil 21.7%. When adding to these values the estimations of the secondary structure reported for the transmembrane region only, the results are in agreement with those obtained experimentally by Yager et al. and Methot et al. The deviations with respect to these experimental estimations are alpha-helix +2.8%, beta-sheet -4/-5% and turn + coil +3/+2%, respectively. Considering the predictions made for individual subunits, the best approximation was obtained for the alpha subunit, with deviations of -0.2% for alpha-helix, -2.5/-1.5% for beta-sheet, and +0.9/+1.9% for turn + coil. The prediction was used to infer the residues involved in forming three helices that presumably flank the ligand-binding pocket and to propose mechanism for transferring the information of the ligand binding to the ion channel. PMID- 9365995 TI - Clinical challenges in the psychopharmacology of schizophrenia. AB - Better pharmacological treatments for schizophrenia have elevated the expectations of patients and families and allow a wider range of therapeutic options for clinicians. At the same time, the treatment of schizophrenia has become more complex, and clinical decisions must often be made in the absence of unambiguous empirical guidelines. Under these circumstances, good patient care is based on clinical judgement informed by available clinical research. This issue of the Schizophrenia Bulletin reviews research in areas that represent major clinical challenges in the psychopharmacology of schizophrenia. PMID- 9365994 TI - At issue: genes, experience, and chance in schizophrenia--positioning for the 21st century. AB - Genetic factors make important contributions to the etiologies of schizophrenia. The mode of familial inheritance remains unknown, but it is highly likely that multiple genes and idiosyncratic environmental factors are involved. Rapidly evolving genetic technologies have been applied in the genetic analysis of schizophrenia, and several genomic regions have been posited as harboring susceptibility genes. Currently, the strongest evidence implicates chromosomes 6 and 8, but these linkages are not yet confirmed. In this article we discuss genetic risk factors, gene-environment interaction, the feasibility of genetic testing, psychiatric genetic counseling, and the dangers of genetic discrimination as they apply to schizophrenia. We also address and correct specific misconceptions about the genetics of schizophrenia held by many in the scientific community and in the media, and discuss a blueprint for future genetic research and informed dissemination of findings to the public and to lawmakers. PMID- 9365996 TI - Neuroleptic intolerance. AB - This article reviews antipsychotic medication side effects, especially those that require the physician to discontinue or the patient to be noncompliant with otherwise useful medication. They include such common problems as extrapyramidal syndromes (dystonia, akathisia, drug-induced Parkinsonism, tardive dyskinesia), sedation, weight gain, and sexual dysfunction, as well as less frequent concerns, such as seizures, neuroleptic malignant syndrome, agranulocytosis, torsade de pointes, hepatitis, and dermatological and ophthalmological syndrome. The adverse events associated with some of the new antipsychotic drugs are included. Available information about individual susceptibility to side effects is addressed by syndrome. PMID- 9365997 TI - Treatment of tardive dyskinesia. AB - Although the new generation of atypical antipsychotic agents could some day eliminate concerns about tardive dyskinesia (TD), this disorder remains a significant clinical problem for both patients and physicians. Fortunately, many, if not most, cases of TD are mild. For patients with mild to moderate TD, therapeutic efforts are primarily directed at minimizing neuroleptic exposure or, when possible, changing to atypical agents. Most cases of TD do not seem to progress, suggesting that the risk of remaining on typical neuroleptics is probably small. Patients with moderate to severe forms of TD present greater challenges. These patients frequently require medication to suppress their dyskinesias. A variety of suppressive agents have been tried with limited success. No treatment strategy has emerged that is clearly superior or even successful in most patients. Increasing doses of typical neuroleptics may be useful for short-term suppression; however, the long-term efficacy and risk of this strategy have not been studied carefully. Data on atypical neuroleptics are scant. Clozapine's short-term suppressive effects seem, at best, weak, but patients may improve with long-term treatment. Medications with relatively few side effects that may have suppressive efficacy for some patients include calcium channel blockers, adrenergic antagonists, and vitamin E. Gamma-amino-butyric acid agonists agents and dopamine depleters are frequently useful, but have troubling side effects of their own. A variety of other medications have been employed, but are not well studied. For patients with tardive dystonia, anticholinergic agents or botulinum toxin has been particularly effective. Efforts to understand the neurobiology of TD may shed light on this persistent clinical conundrum. PMID- 9365998 TI - Seizures and schizophrenia. AB - Patients with epilepsy develop psychosis or schizophrenia at a rate exceeding that expected if the two disorders were independent. Similarly, patients with schizophrenia are more prone to seizures than the general population. This excess vulnerability may be conferred by the neuropathological substrate of schizophrenia itself or by the secondary effects of the illness, including exposure to psychotropic medications that lower the seizure threshold. Neuropathological investigations into the anatomic substrate of seizures in patients with psychosis or schizophrenia are consistent with the notion that there are neurodevelopmental abnormalities involving the mesial temporal lobe. Finally, clinical recommendations for the evaluation and pharmacological management of patients with schizophrenia who have one or more seizures are described. PMID- 9365999 TI - Sexuality, reproduction, and family planning in women with schizophrenia. AB - This article reviews data about how schizophrenia affects sexuality, pregnancy, the puerperium, parenting, and family planning. Women with schizophrenia have high rates of coerced sex, sexual risk behavior, and unwanted pregnancies. High rates of obstetric complications and custody loss increase morbidity for women and their offspring. Since untreated psychosis increases these problems, the risks of withholding pharmacotherapy must be weighed against the risks of prescribing medications during pregnancy. The puerperium is a time when women are especially vulnerable to exacerbations of schizophrenia. Mothers with schizophrenia may have a reduced ability to read children's cues, and they often have weak social support networks. Their children may be more difficult to raise than other children. Parenting rehabilitation can address some of these problems. Often, women with schizophrenia who are sexually active and do not wish to become pregnant do not use contraception. Incorporating family planning measures into mental health care delivery systems may reduce unwanted pregnancies. PMID- 9366000 TI - Determinants of medication compliance in schizophrenia: empirical and clinical findings. AB - Advances in psychopharmacology have produced medications with substantial efficacy in the treatment of positive and negative symptoms of schizophrenia and the prevention of relapse or symptom exacerbation after an acute episode. In the clinical setting, the individual patient's acceptance or rejection of prescribed pharmacological regimens is often the single greatest determinant of these treatments' effectiveness. For this reason, an understanding of factors that impede and promote patient collaboration with prescribed acute and maintenance treatment should inform both pharmacological and psychosocial treatment planning. We review the substantive literature on medication adherence in schizophrenia and describe a modified health belief model within which empirical findings can be understood. In addition to factors intrinsic to schizophrenia psychopathology, medication-related factors, available social support, substance abuse comorbidity, and the quality of the therapeutic alliance each affect adherence and offer potential points of intervention to improve the likelihood of collaboration. Because noncompliance as a clinical problem is multidetermined, an individualized approach to assessment and treatment, which is often best developed in the context of an ongoing physician-patient relationship, is optimal. The differential diagnosis of noncompliance should lead to interventions that target specific causal factors thought to be operative in the individual patient. PMID- 9366001 TI - The evaluation and treatment of first-episode psychosis. AB - A first episode of psychosis is a traumatic experience for patients and families. At the time of initial evaluation, the differential diagnosis should include a broad range of neurological, general medical, and psychiatric conditions. Methodological advances in operationally defining illness onset, "offset," and remission have allowed more careful studies of treatment response in first episode patients. These studies strongly support the efficacy of antipsychotic medication as both acute and maintenance treatment for patients with a first episode of psychosis. The optimal duration of maintenance treatment, however, has not been determined, and patients at low risk for relapse following medication withdrawal cannot be identified with specificity. First-episode psychotic patients typically experience 12 to 24 months of psychosis before receiving treatment, and a long duration of untreated psychosis may be associated with a poorer treatment response. Early intervention may improve outcome in first episode psychosis, and the use of novel antipsychotics with improved efficacy and fewer side effects may improve medication compliance and reduce morbidity associated with repeated relapses. PMID- 9366002 TI - Evaluation of treatment-resistant schizophrenia. AB - A systematic approach to the evaluation and characterization of treatment resistance in schizophrenia has become increasingly important since the introduction of clozapine, risperidone, and olanzapine. The need for accurate evaluation will increase with the introduction of the next generation of antipsychotic medications. People with schizophrenia may manifest a poor response to therapy secondary to intolerance of medication, poor compliance, or inappropriate dosing, as well as true resistance of their illness to antipsychotic drug therapy. Clinicians facing the decision of when to change from one antipsychotic to another must clearly understand the appropriate length of a trial and what target symptoms respond to antipsychotics in order to maximize the response in patients with treatment-resistant schizophrenia. PMID- 9366003 TI - HIV/AIDS risks as a consequence of schizophrenia. AB - Given both the rapid rise in the prevalence of HIV infection among adolescent and adult males (0.6%) and females (0.1%) in the United States from 1984 to 1992 and the associations among HIV, injection drug abuse, homosexuality, and sexual promiscuity, it is important to determine whether individuals diagnosed with schizophrenia are at a higher than average risk of HIV infection. Stereotypes from the recent past about sexuality in both male and female patients were examined as an integral part of a literature review. Data from a dozen or so studies conducted since 1990 confirm and strengthen the impressions that persons with schizophrenia should be considered a group with a much higher than average risk for developing HIV/AIDS and that they have special needs for protection as a public health measure. Mental health service providers need to be aware of these findings. PMID- 9366004 TI - Physical and sexual assault history in women with serious mental illness: prevalence, correlates, treatment, and future research directions. AB - An emerging body of research on the physical and sexual abuse of seriously mentally ill (SMI) women documents a high incidence and prevalence of victimization within this population. While causal links are not well understood, there is convergent evidence that victimization of SMI women is associated with increased symptom levels, HIV-related risk behaviors, and such comorbid conditions as homelessness and substance abuse. These abuse correlates may influence chronicity, service utilization patterns, and treatment alliance. This article reviews the research literature on the prevalence, symptomatic and behavioral correlates, and treatment of abuse among SMI women, particularly women with schizophrenia. Within each topic, we discuss relevant research findings, limitations of available studies, and key questions that remain unanswered. We also discuss mechanisms that may underlie the relationship between trauma and schizophrenia-spectrum disorders. We conclude by outlining directions for future research in this area. PMID- 9366005 TI - First person account: how I cope. AB - The article that follows is part of the Schizophrenia Bulletin's ongoing First Person Account series. We hope that mental health professionals--the Bulletin's primary audience--will take this opportunity to learn about the issues and difficulties confronted by consumers of mental health care. In addition, we hope that these accounts will give patients and families a better sense of not being alone in confronting the problems that can be anticipated by persons with serious emotional difficulties. We welcome other contributions from patients, ex patients, or family members. Our major editorial requirement is that such contributions be clearly written and organized, and that a novel or unique aspect of schizophrenia be described, with special emphasis on points that will be important for professionals. Clinicians who see articulate patients, with experiences they believe should be shared, might encourage these patients to submit their articles to First Person Accounts, Office of Scientific Information, NIMH, 5600 Fishers Lane, Rm. 10-85, Rockville, MD 20857. PMID- 9366007 TI - Postoperative dissociation of blood levels of cortisol and adrenocorticotropin after coronary artery bypass grafting surgery. AB - The regulation of the hypothalamo-pituitary-adrenal (HPA) axis in the operative and perioperative period of major surgical procedures is necessary for successful adaption to surgical stress. We report evidence on an altered response of HPA axis regulation in patients who underwent coronary artery bypass grafting (CABG) surgery. Plasma levels of adrenocorticotropin (ACTH), beta-endorphin, and cortisol were determined with radio-immune assay in 50 males for elective CABG surgery. The patients received general anesthesia using a balanced technique with sufentanil, isoflurane, and midazolam. Pre- and intraoperatively, there was no significant increase in plasma cortisol, ACTH, and beta-endorphin levels. On the evening of surgery, all plasma hormone levels were increased. On the evening of the first and second postoperative day, plasma ACTH and beta-endorphin levels returned to the preoperative baseline values. During the same time interval, plasma cortisol levels were significantly elevated and remained high until the end of the study period (p < 0.001). Our results indicate an altered regulation of the HPA axis in the postoperative period of patients after CABG surgery, as they are compatible with similar results in patients after major abdominal surgery, burned patients, and critically ill patients. Therefore, it is assumed that the finding of a postoperative dissociation between ACTH and cortisol is a result of the severity of perioperative adaptive mechanisms rather than of the specific conditions related to cardiac surgery. PMID- 9366006 TI - Novel estrogens and their radical scavenging effects, iron-chelating, and total antioxidative activities: 17 alpha-substituted analogs of delta 9(11)-dehydro-17 beta-estradiol. AB - Antioxidant effects of N,N-dimethyl-p-toluidine, p-cresol, and p (hydroxy)thioanisol 17 alpha-substituted analogs of 17 beta-estradiol and their delta 9(11)-dehydro homologs were investigated using four different in vitro models: rat synaptosomal lipid peroxidation induced by Fenton's reagent, Fe(II) chelating activities, the formation of superoxide anion radicals, and total antioxidative activity. Whereas the classical estrogen 17 beta-estradiol as well as selected phenolic compounds was only moderately inhibiting iron-dependent lipid peroxidation and stimulating total antioxidative activity, besides delta 9(11)-dehydro-17 beta-estradiol (J 1213), novel estrogens such as C-17-oriented side chain analogs of 17 beta-estradiol (J 843, J 872, and J 897) and delta 9(11) dehydro homologs (J 844, J 864, and J 898) directly altered the iron redox chemistry and diminished the formation of superoxide anion radicals generated by a xanthine/xanthine oxidase-dependent luminescence reaction to a great extent. These results suggest that definite modifications in the chemical structure of 17 beta-estradiol, e.g., the introduction of a delta 9(11)-double bond and/or p cresol as well as p-(hydroxy)thioanisol C-17 substitution, may result in substantial changes in their antioxidant behavior. These compounds may be drug candidates for treating pathologies related to free radical formation. PMID- 9366008 TI - Synthesis of [3 alpha-3H]7-dehydrocholesterol via stable tritiated 4-phenyl-1,2,4 triazoline-3,5-dione derivative. AB - Synthesis of [3 alpha-3H]7-dehydrocholesterol is described via protection of the 5,7-diene system in 7-dehydrocholesterol as the Diels-Alder adduct with 4-phenyl 1,2,4-triazoline-3,5-dione followed by oxidation of the hydroxyl group to give the 3-oxo adduct. Reduction of the keto adduct with [3H]sodium borohydride produced the adduct of [3 alpha-3H]7-dehydrocholesterol from which the radiolabeled sterol was obtained via treatment with lithium aluminum hydride. The advantage of the method is that highly labeled [3 alpha-3H]7-dehydrocholesterol can be prepared. Further, unlike 7-dehydrocholesterol, its adduct with 4-phenyl 1,2,4-triazoline-3,5-dione is stable and can be stored. This allows the preparation of small batches of [3 alpha-3H]7-dehydrocholesterol for immediate use in biological experiments, and losses due to decomposition of excess radiolabeled 7-dehydrocholesterol are minimized. PMID- 9366009 TI - The effect of opioid antagonists in local regulation of testicular response to acute stress in adult rats. AB - The present study examined the effects of naloxone (N) and naltrexone methobromide (NMB; an opioid receptor antagonist that does not cross the blood brain barrier) on testicular steroidogenesis during acute immobilization stress (IMO; 2 h) in adult rats. Unstressed rats as well as IMO rats were treated by unilateral intratesticular injection of N (20 micrograms/testis), NMB (36 micrograms/testis), or vehicle at the beginning of and at 1 h of the IMO period. In IMO rats serum T levels were significantly reduced, while serum luteinizing hormone levels were not affected. N and NMB normalized serum T levels in IMO rats and had no effects in controls. In IMO rats the activities of 3 beta hydroxysteroid dehydrogenase (HSD) and P450(17 alpha, lyase) were significantly reduced, while the activity of 17 beta-HSD was not affected. N and NMB antagonized the inhibitory effect of IMO on 3 beta-HSD and P450(17 alpha, lyase) but did not alter enzyme activity in freely moving rats. Acute IMO decreased basal and human chorionic gonadotropin-stimulated androgen production by hemitestis preparation, but N (10(-4) M) added directly to the incubation medium blocked the decrease and had no effect on testes from freely moving control rats. These results support the conclusion that endogenous opioid peptides are potentially important paracrine regulators of testicular steroidogenesis under stress conditions. PMID- 9366010 TI - The synthesis and in vitro activity of some delta 7,9(11)-lanostadienes. AB - The synthesis of delta 7,9(11)-lanostadiene derivatives functionalized at C(32) starting from 3 beta-acetoxy-7 alpha,32-epoxylanostan-11-one has been presented. The delta 7,9(11) moiety was efficiently introduced in three steps in 71% yield by the regioselective abstraction of allylic 8 beta hydrogen. The formyl group of the key intermediate, 3 beta-benzoyloxylanosta-7,9(11)-dien-32-al, has been stereoselectively alkylated into (32S) derivative, whereas its oxidation unexpectedly afforded 3 beta-benzoyloxy-7-oxolanost-8-ene-32,11 alpha-lactone and not the corresponding acid. delta 7,9(11)-lanostadienes possessing HC(32)=O, C(32) [symbol: see text] N, HC(32S)CH3OH, H2C(32)OH, as well as some 11-keto lanostenes, were tested in vitro against several purified cholesterogenic enzymes showing moderate activity, with most the active aldehyde 16 having IC50 = 86 microM. PMID- 9366011 TI - Expression and hemocyte-targeting of a Campoletis sonorensis polydnavirus cysteine-rich gene in Heliothis virescens larvae. AB - The polydnavirus associated with the parasitic wasp Campoletis sonorensis is injected into the lepidopteran insect, Heliothis virescens, during parasitization, after which viral gene products suppress the cellular immune system of the hosts. Four related cysteine-rich polydnavirus gene have been identified in parasitized H. virescens larvae and grouped into a family. In this study, we investigated the expression and hemocyte targeting of the cysteine-rich VHv1.4 protein. Full-length and truncated VHv1.4 proteins were produced in a bacterial expression system, and the purified proteins were used to raise polyclonal antisera. In immunoblots the VHv1.4 protein was detected in parasitized insects as early as 6 h and throughout the entire course of parasitism. The VHv1.4 protein appeared predominantly in the plasma fraction of hemolymph from parasitized larvae, suggesting that this protein is secreted. The VHv1.4 protein expressed from a recombinant baculovirus was secreted in two lepidopteran cell lines and in larvae injected with the recombinant virus. Digestion with endoglycosidases suggests that the VHv1.4 protein is glycosylated at multiple N-glycosylation sites. Immunofluorescence assays showed that the VHv1.4 protein binds to the hemocytes, most notably the granulocytes, in H. virescens larvae. After binding, the VHv1.4 protein was internalized, probably by endocytosis. Specific binding of the VHv1.4 to granulocytes implies an important function in the suppression of host cellular encapsulation response. PMID- 9366012 TI - Digestion of phosphatidylcholines, absorption, and esterification of lipolytic products by Aeshna cyanea larvae as studied in vivo and in vitro. AB - Digestion and absorption of phosphatidylcholine by Aeshna cyanea larvae were studied in vivo and in vitro with the isolated digestive juice and isolated midgut. The experiments were performed with stable ether analogues (1-alkyl-2 acyl-,1,2-dialkyl phosphatidylcholine, and 1-monoalkyl-lysophosphatidylcholine), with radioactive 1,2-diacylphosphatidylcholine alternatively labelled in the acyl and choline moieties, and with several phosphatidylcholine derivatives (1- [1 14C]acyl- and 1-[3H] alkyl-lysophosphatidylcholine, [1-14C]oleic acid, [2 14C]glycerol, phosphoryl[methyl-14C]choline, and [methyl-14C]choline). Chromatographic analyses of the digestion products revealed that phosphatidylcholine was degraded via two interconnected hydrolytic pathways involving phospholipase C, phospholipase A2, lipase, and alkaline phosphatase. Complete hydrolysis by these pathways yielded the same four end products: free fatty acid, glycerol, choline, and Pi, which were absorbed by the midgut enterocytes. Of the intermediate hydrolysates, lysophosphatidylcholine, monoacylglycerol, and possibly phosphorylcholine were also absorbed. Radiolabelled oleic acid, glycerol, lysophosphatidylcholine and monoacylglycerol (as judged from monoacylglycerol absorption) were incorporated into phospholipids and acylglycerols of the midgut enterocytes and were released into the haemolymph primarily in the form of diacylglycerols. In the case of glycerol ingestion, a small fraction of haemolymph radioactivity was associated with free glycerol and glycerolphosphate. After absorption by the enterocytes, radiolabelled choline was partly oxidized to betaine, partly phosphorylated, and partly incorporated into lyso- and phosphatidylcholine. It was recovered from the haemolymph predominantly as free choline, phosphorylcholine, and betaine. PMID- 9366013 TI - Chymotrypsin inhibitors in mosquitoes: activity profile during development and after blood feeding. AB - Chymotrypsin and trypsin inhibitors persist throughout all developmental instars of Aedes aegypti. After a blood meal, inhibitor activity against chymotrypsin was more than double that of sugar-fed females, but only weak activity was detected in midguts where proteinase inhibitors has been thought to regulate proteinases during blood digestion. A fourfold increase in the ratio of abdominal/thoracic inhibitor activity after the blood meal strongly suggested that fat body, or other abdominal tissues, represent the major source of inhibitor. Chymotrypsin inhibitor activity was deposited in maturing oocytes. Similar results were obtained with blood-fed Anopheles albimanus. Chymotrypsin inhibitor was active against different mosquito proteinases and against bovine alpha-chymotrypsin and trypsin, but not against subtilisin, pancreatic elastase, or fungal proteases; chymotrypsin inhibitors did not interfere with bacterial growth. The hypothesis on the regulation of blood digestion through the action of proteinase inhibitors during the gonotrophic cycle was abandoned and its involvement in the phenoloxidase cascade in the mosquito egg chorion is suggested instead. PMID- 9366014 TI - Native vitellins are modified during ovarian development in the stick insect Carausius morosus (Br.). AB - Vitellins from ovarian follicles and newly laid eggs of the stick insect Carausius morosus were examined by ion exchange chromatography on a HPLC Mono Q column. Under these conditions, vitellins from newly laid eggs resolved as two distinct peaks, referred to as VtA and VtB, that eluted at 8.5 and 12.0 min, respectively. On native gels, both VtA and VtB separated into two different variant forms (VtA' and VtA", VtB' and VtB"). By two-dimensional gel electrophoresis, VtA' and VtA" were shown to contain polypeptides A1, A2 and A3. On the other hand, VtB' and VtB" appeared to comprise polypeptides B1 and B2 and B1, A1, A2, B2 and A3*, respectively. A similar Vt polypeptide composition was also observed by size-exclusion chromatography of vitellins from newly laid eggs. Vitellins from early vitellogenic ovarian follicles resolved into a single chromatographic peak at 7.5 min that coeluted with a major peak from the hemolymph of egg-laying females. Ovarian follicles progressively more advanced in development exhibited a more complex chromatographic profile, consisting of three separate peaks. By two-dimensional gel immunoelectrophoresis, vitellins from ovarian follicles appeared to consist of two closely related, immunologically cross-reacting antigens that gradually shifted apart as ovarian development proceeded to completion. By size-exclusion chromatography, each Vt from ovarian follicles was shown to consist of a unique set of polypeptides different from those listed above. Single ovarian follicles were fractionated into yolk granules and yolk fluid ooplasm and tested by immunoblotting against Mab 12. Under these conditions, VtA variant forms in yolk granules and yolk fluid ooplasm reacted differently. Sections from ovarian follicles in different developmental stages were exposed to Mab 12 and stained with a peroxidase-conjugated, goat anti-mouse antibody. Regardless of the developmental stage attained, staining for peroxidase was restricted to free yolk granules, suggesting that native vitellins in stick insects are structurally modified upon fusion into the yolk fluid ooplasm. PMID- 9366015 TI - A cell-based immunobiosensor with engineered molecular recognition--Part III: Engineering molecular recognition. AB - We have been studying the feasibility of exploiting the recognition and amplification abilities of living immune cells for the development of hybrid immunosensors. Our group has previously reported that cell metabolic activation responses, induced by calcium ionophore A23187, can be directly transduced using calorimetric transducers, and that enzyme systems can be integrated to enhance sensing response time and output. In this study our goal was to determine the feasibility of transducing the thermal activation responses of mast cells molecularly engineered to a specific antigen. Rat peritoneal mast cells were sensitized to the model antigenic analyte dinitrophenylated-albumin (DNP-A), with monoclonal anti-DNP-A IgE, and challenged with antigen at final concentrations of 10 or 100 ng/ml. The addition of antigen resulted in the molecular triggering of cell activation, yielding thermal responses similar to those obtained previously with the ionophore model. A peak thermal response of 1.7 microW/5 x 10(5) cells was obtained within approximately 7 min of addition of antigen. The incorporation of selected amplification enzyme systems increased peak thermal outputs approximately three-fold, and reduced peak thermal response times to less than 3 min. A preliminary regression analysis of these data suggests a quantitative relationship exists between analyte concentration and peak thermal response (R = 0.988). These results support the feasibility and potential versatility of cell based immunobiosensors for the selective detection and quantification of immunological analytes of interest. PMID- 9366016 TI - Quartz crystal microbalances for quantitative biosensing and characterizing protein multilayers. AB - The use of quartz crystal microbalances (QCMs) for quantitative biosensing and characterization of protein multilayers is demonstrated in three case studies. Monolayers of QCM-based affinity biosensors were investigated first. Layers of a thiol-containing synthetic peptide constituting an epitope of the foot-and-mouse disease virus were formed on gold electrodes via self-assembly. The binding of specific antibodies to epitope-modified gold electrodes was detected for different concentrations of antibody solutions. Oligolayers were studied in a second set of experiments. Dextran hydrogels were modified by thrombin inhibitors. The QCM response was used in a competitive binding assay to identify inhibitors for thrombin at different concentrations. Multilayers of proteins formed by self-assembly of a biotin-conjugate and streptavidin were investigated next. The QCM frequency response was monitored as a function of layer thickness up to 20 protein layers. A linear frequency decay was observed with increasing thickness. The decay per layer remained constant, thus indicating perfect mass coupling to the substrate. Frequency changes a factor of four higher were obtained in buffer solution as compared to measurements in dry air. This indicates a significant incorporation of water (75% weight) in the protein layers. This water behaves like a solid concerning the shear mode coupling to the substrate. The outlook discusses briefly the need for controlled molecular engineering of overlayers for subsequent QCM analysis, and the importance of an additional multiparameter analysis with other transducer principles and with additional techniques of interface analysis to characterize the mechanical coupling of overlayers as biosensor coatings. A promising trend concerns the use of QCM-arrays for screening experiments. PMID- 9366017 TI - Photosensitive polyurethanes applied to the development of CHEMFET and ENFET devices for biomedical sensing. AB - Chemical microsensors based on ion-selective field effect transistor (ISFET) transducers with ion-selective and enzymatic membranes have been fabricated. In this case, photolithographically patterned membranes based on acrylated urethanes have been developed and applied onto the gate area of ISFET chips. Aliphatic urethane diacrylate has been used for K+ and NH+4 membranes, while a photocurable hydrogel formulation based on other type of acrylated urethane has been optimized for urea-FET sensors. Resulting potassium and ammonium sensors show similar performances to those found when PVC membranes are employed. An integrated packaging process for ISFET-based sensors has been developed giving the possibility of carrying out most of the encapsulation on wafer level. For this purpose, a photocurable polyurethane encapsulant formulation has been optimized to be microstructured by photolithography. Finally, a preliminary study of biocompatibility of photosensitive formulations containing urethane oligomers has been performed in order to examine future applications in biomedical and clinical analysis. PMID- 9366018 TI - Nucleic-acid immobilization, recognition and detection at chronopotentiometric DNA chips. AB - Wide-scale DNA testing requires the development of fast, small, easy-to-use biosensing devices. Various synthetic oligonucleotides and DNA have thus been immobilized onto microfabricated thick-film carbon transducers for performing several new nucleic-acid assay protocols. These include hybridization detection of nucleic acid sequences, determination of small molecules (drugs, pollutants) based on their collection into the dsDNA layer or via monitoring their effect upon the intrinsic DNA oxidation signal, and direct adsorptive stripping measurements of ultratrace levels of nucleic acids. Transduction of these DNA recognition processes is accomplished by a new highly-sensitive constant-current stripping chronopotentiometric operation. Comparison to traditional electrodes indicates that the biosensing performance is not compromised by the use of mass producible disposable transducers. Such thick-film DNA biosensors have been coupled to a compact, user-friendly, hand-held analyzer. Applicability for the detection of sequences from M. tuberculosis and HIV-1 DNAs is illustrated. Such activity in the author's laboratory, aimed at developing DNA-coated screen printed electrodes, is reviewed. PMID- 9366019 TI - Quartz balance DNA sensor. AB - Single-strand DNA-containing thin films were deposited onto quartz oscillators by the Langmuir-Blodgett technique towards the realization of a device capable of sensing the presence of the complementary DNA sequences which hybridize with the immobilized ones. DNA, once complexed with aliphatic amines, appears as a monolayer in a single-stranded form by X-ray small angle scattering. A quartz nanobalance is then utilized to monitor mass increment related to specific hybridization with a complementary DNA probe. The crystal quartz nanobalance, capable of high sensitivity, indeed appears capable of obtaining a prototype of a device capable of sensing the occurrence of particular genes or sequences in the sample under investigation. The validity of the nanogravimetric assay was confirmed by independent fluorescence measurements utilizing DAPI and a CCD camera. PMID- 9366020 TI - Effects of acetonitrile on horseradish peroxidase (HRP)-anti HRP antibody interaction. AB - The effects of the water-miscible organic solvent acetonitrile on the enzymatic activity of horseradish peroxidase (HRP) and on HRP-anti-HRP binding have been investigated. Results showed that both the catalytic activity of HRP and the binding ability of the antibody were affected on increasing the concentration of the organic solvent. The activity of HRP varied with the organic composition of the solvent, indicating that the conformation of the enzyme was affected. The binding ability of the antibody also decreased significantly with an increase of the organic composition of the solvent, and in absolute acetonitrile, the activity of the antibody is about 500 times lower than that in aqueous medium. Binding reversibility experiments indicated that the antibody was not irreversibly damaged in solutions with acetonitrile composition greater than 80% and below 40%; however, an irreversible decrease in the binding was observed in solutions with an acetonitrile composition between 40 and 80%. The reduction in the binding ability is probably due to the irreversible conformation changes in the antibody. PMID- 9366021 TI - Photochemically-activated electrodes: application in design of reversible immunosensors and antibody patterned interfaces. AB - Antigen monolayers assembled onto Au electrodes associated with a quartz crystal act as electrochemical or microgravimetric quartz-crystal-microbalance (QCM) sensing interfaces for the complementary antibody. Electrochemical analysis of the antibody (Ab) is based on the insulation of the antigen monolayer electrode by the associated Ab towards a redox probe in the electrolyte solution. Ferrocene modified glucose oxidase (Fc-GOx) and glucose are employed as redox probes for the amperometric transduction of the Ab association to the electrode. Bioelectrocatalyzed oxidation of glucose provides an electrochemical route to amplify the antigen-Ab complex formation. Electrochemical analysis of the dinitrophenyl antibody, DNP-Ab, by a dinitrophenyl-lysine monolayer electrode is presented. QCM analysis of the Ab is based on the frequency changes of the quartz crystal resulting from the association of the Ab to the crystal assembly. This method is discussed with the analysis of the fluorescein antibody, Flc-Ab, using a fluorescein monolayer-modified quartz crystal. A novel method to tailor reversible immunosensor devices by the application of photoisomerizable antigen monolayers on electrodes is presented. The antigen is modified by photoactive units exhibiting reversible photoisomerizable properties. In one photoisomer state, the antigen exhibits affinity for the Ab and enables its electrochemical or QCM analysis. Photoisomerization to the complementary state perturbs the antigen structure and the monolayer lacks affinity for the Ab. This enables the washing-off of the Ab and the regeneration of the actively sensing interface by a second illumination process that restores the antigen monolayer-modified surface. This method is exemplified by the development of a reversible DNP-Ab sensing electrode. N-Mercaptobutyl dinitrospiropyran was assembled as a photoisomerizable monolayer on a Au electrode. The dinitrospiropyran monolayer, SP-state, exhibits affinity for the DNP-Ab and enables the amperometric detection of the Ab using Fc GOx and glucose as redox probe. The complementary photoisomerized protonated dinitromerocyanine monolayer, MRH(+)-state, lacks affinity for the DNP-Ab. By photoisomerization of the DNP-Ab associated with the SP-monolayer electrode to the MRH(+)-monolayer state, the DNP-Ab is washed-off, and by a second illumination process, the MRH(+)-monolayer is re-isomerized to the SP-monolayer assembly, which is the active interface for further analysis of the DNP-Ab. Cyclic amperometric detection of the DNP-Ab by the photoisomerizable dinitrospiropyran monolayer is demonstrated. The association of the DNP-Ab to the SP-monolayer electrode and the dissociation of the Ab from the MRH(+)-monolayer electrode are confirmed by QCM experiments using a dinitrospiropyran monolayer modified quartz crystal. The insulating features of an antigen-Ab complex on a conductive surface and the photochemically controlled association of an antibody to a photoisomerizable monolayer assembled onto the surface were used to develop means for micropatterning of surfaces by the antibody. A dinitrospiropyran antigen monolayer was assembled onto conductive ITO glass. A DNP-Ab solution was used as 'ink solution' to pattern the surface. The Ab-pattern was imaged by electrochemical copper deposition onto the Ab-lacking surface domains. The dinitrospiropyran monolayer assembled onto ITO or Pyrex glass surfaces was employed as an active interface for the photolithographic patterning of the surface with the DNP-Ab. (ABSTRACT TRUNCATED) PMID- 9366022 TI - Detection of staphylococcal enterotoxin B employing a piezoelectric crystal immunosensor. AB - This paper reports on a study concerning the development of a biochemical sensor for Staphylococcal Enterotoxin B (SEB), a substance within the bracket of biological warfare. A 20 MHz piezoelectric quartz crystal sensor device was employed in a flow injection system. The assay for SEB is based on a competition scheme using polyclonal antibodies (anti-SEB). Three parameters, i.e. the flow rate in the flow cell, the incubation time and the anti-SEB concentration, were optimized. A detection limit of 0.1 microgram/ml was obtained, whereas at concentrations of SEB of 10 micrograms/ml or higher the sensor response was completely inhibited. The results were compared with a competition enzyme linked immunosorbent assay. PMID- 9366024 TI - Current awareness in biosensors & bioelectronics. PMID- 9366023 TI - Implantation of a refillable glucose monitoring-telemetry device. AB - This study describes the components and short-term in vivo evaluation of an integrated implantable system consisting of an amperometric glucose biosensor, a miniature potentiostat, a FM signal transmitter, and a power supply. The device (dimensions: 5.0 x 7.0 x 1.5 cm) was implanted subcutaneously in healthy mongrel dogs. The biosensor performance was evaluated in vitro prior to implantation using standard solutions simulating the physiological environment. A linear response to glucose concentration was observed throughout the physiological and pathophysiological range (with an upper limit of 25 mM glucose, and a sensitivity of 0.5 microA/mM). The results of short-term subcutaneous implantation of the integrated system demonstrated good agreement between the glucose concentration measured by the biosensor and that obtained using standard glucose determination methods. The delay-time between the tissue glucose level (measured by the biosensor) and the blood glucose level (obtained by standard methodology) was 3-7 min. These results demonstrated the feasibility of data transmission by a telemetry system through the skin of a dog and allowed the commencement of chronic in vivo testing. During the chronic implantation the biosensor was refilled in vivo. A rejuvenation of the sensor's response after refilling was observed suggesting the potential of such sensors for long-term implantation. PMID- 9366025 TI - Stereoselectivity and enantiomer-enantiomer interactions in the binding of ibuprofen to human serum albumin. AB - Binding of ibuprofen (IB) enantiomers to human serum albumin (HSA) was studied using a chiral fluorescent derivatizing reagent, which enabled the measurement of IB enantiomers at a concentration as low 5 x 10(-8) M. Scatchard analyses revealed that there were two classes of binding sites for both enantiomers. For the high affinity site, the number of the binding sites was one for both enantiomers, and the binding constant of R-IB was 2.3-fold greater than that of S IB. The difference in the affinity at the high affinity site may result in the stereoselective binding of IB enantiomers at therapeutic concentrations. It was confirmed that the high affinity site of IB enantiomers is Site II (diazepam binding site) by using site marker ligands. Also, significant enantiomer enantiomer interactions were observed in the binding. The binding data were quantitatively analyzed and a binding model with an assumption of competitive interactions only at the high affinity site simulated the binding characteristics of IB enantiomers fairly well. PMID- 9366026 TI - Species differences for stereoselective hydrolysis of propranolol prodrugs in plasma and liver. AB - Species differences and substrate specificities for the stereoselective hydrolysis of fifteen O-acyl propranolol (PL) prodrugs were investigated in pH 7.4 Tris-HCl buffer and rat and dog plasma and liver subfractions. The (R) isomers were preferentially converted to propranolol (PL) in both rat and dog plasma with the exception of isovaleryl-PL in rat plasma, although the hydrolytic activities of prodrugs in rat plasma were 5-119-fold greater than those in dog plasma. The prodrugs with promoieties (C(=O)CH(R)CH3) based on propionic acid showed marked preference for hydrolysis of the (R)-enantiomers in plasma from both species (R/S ratio 2.5-18.2). On the other hand, the hepatic hydrolytic activities of prodrugs were greater in dog than rat, especially in cytosolic fractions. The hydrolytic activity was predominantly located in microsomes of the liver in rat, while the cytosol also contributed to hepatic hydrolysis in dog. Hepatic microsomal hydrolysis in dog showed a preference for the (R)-isomers except acetyl- and propionyl-PL. Interestingly, in rat liver all types of prodrugs with substituents of small carbon number showed (S)-preference for hydrolysis. The hydrolyses of (R)- and (S)-isomers of straight chain acyl esters in rat liver microsomes were linearly and parabolically related with the carbon number of substituents, respectively, while these relationships were linear for both isomers in dogs. PMID- 9366027 TI - Chirality of the gamma-lactones produced by Sporidiobolus salmonicolor grown in two different media. AB - Sporidiobolus salmonicolor is an aroma-producing yeast which gives a peach-like smell to the culture media. The enantiomeric ratios of the five gamma-lactones produced by this yeast cultivated in two different media were determined by multidimensional gas chromatography (MDGC) on a fused silica capillary column coupled to a modified beta-cyclodextrin column. These ratios remain constant during growth and are not affected by the composition of the medium. The (R) enantiomer is highly predominant (99%) for gamma-decalactone and predominant (68 88%) for gamma-octalactone, gamma-nonalactone, and (Z6)-gamma-dodecenolactone. A ratio close to racemic was found for gamma-dodecalactone. A discussion on the metabolic origin of these lactones is based on the analysis of the enantiomeric ratios obtained. With respect to consumers' preference for products considered as "natural," microbial lactone production may represent a valuable alternative to fruit flavors. The enantiomeric lactone ratios produced by Sporidiobolus salmonicolor are compared with those reported from some fruits. PMID- 9366028 TI - Chiral resolution and absolute configuration of the enantiomers of 5-acetyl-2 methyl-4-methylsulfinyl-6-phenyl-3(2H)-pyridazinone and evaluation of their platelet aggregation inhibitory activity. AB - In a series of 5-acyl-6-phenyl-2,4-substituted-3(2H)-pyridaziones the derivative 1a, with a sulfur stereogenic center, had the most potent activity as human platelet aggregation inhibitor. The resolution of rac-1a was successfully performed by chiral chromatography on Chiralcel OD-R, OD-H, and Chiralpak AD columns and scaled up to a preparative level. The absolute configuration of (-) (S)-1a was determined by X-ray crystallographic analysis. In vitro human platelet aggregation inhibitory activity was evaluated. Both the enantiomers showed IC50 values in the same micromolar range, but the (-)-(S) isomer was slightly more potent [(S)/(R) potency ratio was 4/1]. PMID- 9366029 TI - Steady-state pharmacokinetics of the enantiomers of citalopram and its metabolites in humans. AB - The steady-state pharmacokinetics in serum and urine of the enantiomers of citalopram and its metabolites, demethylcitalopram (DCT) and didemethylcitalopram (DDCT), were investigated after multiple doses of rac-citalopram for 21 consecutive days (40 mg per day) to healthy human subjects who were extensive metabolisers of sparteine and mephenytoin. Comparable pharmacokinetic variability was noted for (+)-(S)-, (-)-(R)- and rac-citalopram. Enantiomeric (S/R) serum concentration ratios for citalopram were always less than unity and were constant during the steady-state dosing interval. A modest, but statistically significant, stereoselectivity in the disposition of citalopram and its two main metabolites was observed. Serum levels of the (+)-(S)-enantiomers of citalopram, DCT, and DDCT throughout the steady-state dosing interval investigated were 37 +/- 6%, 42 +/- 3% and 32 +/- 3%, respectively, of their total racemic serum concentrations. The (+)-(S)-enantiomers of citalopram, DCT, and DDCT were eliminated faster than their antipodes. For (-)-(R)- and (+)-(S)-citalopram, respectively, the serum t1/2 averaged 47 +/- 11 and 35 +/- 4 h and AUCss averaged 4,193 +/- 1,118 h.nmol/l and 2,562 +/- 1,190 h.nmol/l. The observed enantiospecificities were apparently more related to clearance, rather than to distributional mechanisms. PMID- 9366030 TI - Configuration of heptopyranoside and heptofuranoside side chains: 2-anthroate, a powerful chromophore for exciton coupled CD. AB - The absolute configuration of the acyclic side chain of heptopyranosides and heptofuranosides was determined by exciton coupled CD, employing the strongly fluorescent 2-anthroate chromophore. The usage of this chromophore offers significant improvements over previous chemical and spectroscopic procedures since its intense fluorescence greatly facilitates the isolation and HPLC purification at the nanogram scale. The large amplitudes of the bisignate spectra allow CD manipulations in the 1 x 10(-7) M range. PMID- 9366031 TI - Basal secretion of growth hormone in sheep is not influenced by GH feedback. AB - Autoregulation of GH secretion in sheep was examined by intravenous and intracerebroventricular (i.c.v.) administration of human and bovine GH. Intravenous administration of hGH at either 2 mg or 10 mg per sheep failed to alter radioimmunoassayable plasma ovine GH concentrations or plasma somatostatin. Human GH also failed to alter plasma oGH when given at a dose of 50 micrograms i.c.v. Bovine GH (at 50 micrograms or 500 micrograms) i.c.v. did not affect basal plasma oGH or somatostatin, nor did pretreatment with 50 micrograms bGH significantly alter GH response to clonidine stimulation, although the change in plasma GH with stimulation was only half that of controls. These data do not support a major autoregulatory effect on GH secretion in the sheep. PMID- 9366032 TI - Inhibitory effect of sex steroids on guinea-pig airway smooth muscle contractions. AB - We assessed the possible inhibition of airway smooth muscle contraction by progesterone and pregnanolones (5 alpha and 5 beta-reduced). Progesterone and 5 beta-pregnanolone prevented histamine- or carbachol-induced contraction in isolated guinea-pig trachea and potency was related to their respective chemical structure; progesterone was the most potent inhibitor in a concentration dependent manner. The steroids also exhibited calcium antagonist activities in this tissue as assessed by their action on calcium entry in depolarized preparations; this event involved the immediate blockade of the extracellular calcium influx in the muscle cell membrane, indicating a nongenomic action. Classical GABAA antagonists did not block the progesterone response, implying no involvement of the GABAA-receptor complex. Our results suggest a bronchodilating effect induced by sex steroids, and probably by other related compounds, before the genomic mechanisms take place. This nongenomic action of steroids could have potential therapeutic usefulness in the treatment of asthma. PMID- 9366033 TI - Tissue-dependent and developmentally regulated cytosolic thyroid-hormone-binding proteins (CTBPs) in Xenopus. AB - Xenopus cytosolic thyroid-hormone-binding proteins (CTBPs) were examined by a photoaffinity labeling and [125I]T3-binding assay. An affinity-labeled protein of 59 kDa, which was responsible for the major T3-binding activity in adult tissues, was predominant in liver. The 59-kDa CTBP first appeared in significant amounts at the metamorphic climax stage in liver cytosol and continued to be expressed after metamorphosis. Another affinity-labeled CTBP of 38 kDa appeared at the metamorphic climax stage in cytosol from head region, but disappeared after this stage. T3-binding assay using whole cytosol showed that a distinct CTBP, although not photoaffinity-labeled, was present in cytosol from hindlimb bud and gradually disappeared as the hindlimb grew. The cytosol from liver, head region, and hindlimb bud contained high affinity binding sites for T3 with Kd values ranging from 10(-9) to 10(-8) M. These results suggest that there are at least three distinct CTBPs in Xenopus cytosol, which are expressed in a tissue-dependent and developmentally regulated manner. PMID- 9366035 TI - Distribution of tissue kallikreins in lower vertebrates: potential physiological roles for fish kallikreins. AB - Fish skeletal muscle prokallikrein was purified from black sea bass, Centropritis striata, and used for the production of polyclonal antiserum. Tissue proteins from primitive fish and teleosts, an alligator, and an insectivore were resolved by sodium dodecylsulfate-polyacrylamide gel electrophoresis, Western blotted, and probed with fish muscle prokallikrein antiserum. A recurring theme was the presence of approximately 36 and 72 kDa kallikrein-like proteins in skeletal muscle, heart, gill, kidney, and spleen of higher teleosts and in selected tissues of sturgeon, shark, alligator, and mole. The presence of immunoreactive kallikreins in osmoregulatory organs such as the gills of teleosts and the rectal gland of sharks signifies a potential role for these proteins in osmoregulation. Black sea bass, rock bass, and sturgeon contained many immunoreactive kallikreins in their swimbladders, which implicates a role for kallikreins in the regulation of blood flow and vascular permeability to facilitate gas exchange within the bladder. Kallikreins were consistently identified in skeletal muscle and heart of all the species evaluated and may regulate local blood flow, muscle contraction or relaxation, or participate in various transport processes. The antiserum to fish prokallikrein recognized immunoreactive kallikreins from pancreatic tissues from fish and lower vertebrates, but not from the pyloric caecum of sea bass. The wide distribution of tissue kallikrein in lower vertebrates suggests that it may participate in a variety of physiological functions. PMID- 9366034 TI - Purification, characterization and activation of fish muscle prokallikrein. AB - Fish prokallikrein was isolated and characterized from skeletal muscle of the black sea bass, Centropristis striata. The prokallikrein was purified to apparent homogeneity by anion exchange perfusion chromatography and reversed phase high performance liquid chromatography. Initial identification was by its weak immunoreactivity with human tissue kallikrein antiserum. Two-dimensional gel electrophoresis and immunoblotting identified the protein as 36 kDa with a pI of 4.95-5.15. The prokallikrein was trypsin-activated to produce an approximately 36 kDa active enzyme as identified on an SDS-polyacrylamide gel overlayed with a membrane impregnated with the fluorogenic tripeptidyl substrate D-Val-Leu-Arg-7 amino-4-trifluoromethyl-coumarin. A potential dimer at 72 kDa was also enzymatically active. Bass kallikrein cleaved low molecular weight dog kininogen to release kinin peptide as determined by radioimmunoassay. The enzyme's amidolytic activity, with a pH optimum at 9.0, was inhibited by aprotinin, benzamidine, and phenylmethanesulphonyl fluoride, but not by elastatinal, soybean trypsin inhibitor, or limabean trypsin inhibitor. Polyclonal antiserum raised against the purified bass muscle prokallikrein recognized 36 kDa and 72 kDa proteins in bass heart, skeletal muscle, spleen, swimbladder, gill, and kidney by Western blot analyses. The wide distribution of immunoreactive proteins in the tissues suggests a potential physiological role for fish kallikreins in muscle contraction and/or relaxation, the regulation of local blood flow, and in osmoregulation. The detection of fish prokallikrein and its activation leads the way for an evaluation of the impact of kallikreins in fish health and disease processes and for studying the evolution of kallikreins and related serine proteinases. PMID- 9366036 TI - Tricyclic antidepressants suppress spawning and fertilization in the zebra mussel, Dreissena polymorpha. AB - Tricyclic antidepressants (TCAs), which are psychotropic drugs that work in vertebrates by interfering with serotonergic mechanisms, were tested for their effects on the serotonin-elicited spawning behavior of the zebra mussel, Dreissena polymorpha. Exposure of mussels to 10(-4) M imipramine or desipramine for 2 hr prior to serotonin treatment inhibited spawning in male, but not female, zebra mussels (p < 0.05). Clomipramine (10(-4) M) inhibited spawning of both sexes (p < 0.01). Inhibition of spawning was more effective with 2 hr preexposure time than with shorter times (p < 0.0001). Oocytes released in the presence of TCAs had a normal appearance, with no germinal vesicle present; however, fertilization and embryonic development were adversely affected in oocytes released into TCA concentrations as low as 10(-6) M. Oocytes fertilized after TCA treatment rarely developed normally. This is the first report of an inhibitory effect of TCAs on spawning, fertilization, and early embryonic development in any animal. The concentrations that affect embryonic development in zebra mussels are in the same range as therapeutic plasma concentrations in humans. PMID- 9366038 TI - Developmental effects of chronic low-level lead exposure on voltage-gated calcium channels in brain synaptosomes obtained from the neonatal and the adult rats. AB - Effects of chronic low level (1 mg/kg/day) lead exposure were studied on (1) the density and the binding properties of L, N, and P type voltage-gated Ca2+ influx channels (VGCCs), and (2) the depolarization-induced rise in [Ca2+]i in synaptosomes obtained from the brains of the neonatal (postnatal-day-5) and the adult (postnatal-week-20) rats. Lead exposure started prenatally and continued for either up to postnatal-day-5 or up to postnatal-week-20. The KD and the Bmax values for the binding of nifedipine (antagonist of L type channels), omega-CgTx (a specific antagonist of N type channels) and omega-AgaTx (antagonist of P type channels) to VGCCs in the neonatal samples were less then those in the adult samples. Depolarization increased (1) the density and the antagonist binding affinity of VGCCs and (2) increased [Ca2+]i in both the neonatal and the adult samples. The depolarization-induced increase in [Ca2+]i in the neonatal samples was lower than that in the adult samples. Chronic low-level lead exposure decreased the densities of L, N, and P type VGCCs and attenuated the depolarization-induced increase in [Ca2+]i in synaptosomes. Chronic low-level lead exposure, however, did not affect the relative ratio of L, N, and P channels, the affinity of VGCCs for antagonists, and the depolarization-induced increase in antagonist binding to VGCCs in synaptosomes. Thus chronic low-level lead exposure during early development and adulthood may decrease the synthesis of VGCCs but not their antagonist binding-affinity in both the neonatal and the adult rats. PMID- 9366037 TI - Hemolytic action of anionic surfactants of the diacyl lysine type. AB - Amphiphiles induce hemolysis at a given concentration and that would be dependent on their structure. To know this, we have synthesized anionic surfactants derived from lysine and differing in their chain length and we have studied their hemolytic action. The chain length of the surfactants affects their hemolytic behaviour. Surfactants with two chains of 7 or 9 carbons presented biphasic behaviour at a concentration below or above 50 mg/100 ml. However, only the surfactant with two chains of 7 carbons has a protective effect against hypotonic hemolysis. The maximum protection was exerted when the surfactant was added to a 150 mOsmol/L solution. The surfactant is assumed to intercalate into the membrane in an orientated fashion and prevent the hypotonic hemolysis. For this hemolytic behaviour the presence of two chains of 7 carbons seems to be necessary. PMID- 9366039 TI - Effect of 3-amino-1-propanol on the phosphatidylinositol (PI) and glycosyl phosphatidylinositol (GPI) systems of Tetrahymena. AB - 3-Amino-1-propanol (AP), a substance replacing ethanolamine in phosphatidylethanolamine (PE) significantly reduced 32P incorporation to phosphatidylinositol (PI) and glycosyl-phosphatidylinositol (GPI) in the unicellular organism Tetrahymena pyriformis. At 10 mM, AP completely inhibited the incorporation of 32P into PI. 3H-arachidonate incorporation into PI was also inhibited, while that into diacylglycerol (DAG) was high. The experiments indicate the presence and metabolism of inositol phospholipids and GPI in T. pyriformis. PMID- 9366040 TI - Neurotoxic action of six pyrethroid insecticides on the isolated sciatic nerve of a frog (Rana ridibunda). AB - The neurotoxic action of six pyrethroid insecticides, four type II, (flucythrinate, deltamethrin, fenvalerate, fluvalinate) and two type I (cis- and trans-permethrin) was compared on the isolated sciatic nerve of frog. The nerve was exposed to pyrethroids for 30 min and action potentials were recorded for more than 45 hr after exposure. From the plots of the amplitude of the compound action potential vs time, it was possible to estimate, for each compound, the minimum effective concentration, the concentration which is required to reduce the amplitude of the compound action potential to 50% of its control value (mEC50). Flucythrinate was the most toxic compound, while toxicity decreased in the value: deltamethrin > fenvalerate > fluvalinate >> cis-permethrin > trans permethrin. Low neurotoxicity of cis-permethrin and trans-permethrin (type I pyrethroids) was expected. The neurotoxicity of type I pyrethroids is mainly due to an action at the synapse, which are not present in the frog sciatic nerve preparation. The relative potencies of the four type II compounds agree with their acute toxicity estimated using the LD50. PMID- 9366042 TI - Bibliography of Comparative biochemistry and physiology C generated from the Current awareness in biological sciences database. PMID- 9366041 TI - Nitro aryl 1,4-dihydropyridine derivatives: effects on Trypanosoma cruzi. AB - A series of nitro aryl 1,4-dihydropyridine derivatives produced inhibition of both cell growth and oxygen consumption on Tulahuen and LQ strains, and clone Dm 28c of epimastigotes of Trypanosoma cruzi. Nicardipine was found to be the most potent derivative in both growth cell (I50 = 70 microM) and oxygen uptake (I50 = 26 microM in intact parasites, I50 = 325 microM in situ mitochondria). A correlation between the inhibitory effects on the growth cell and the apparent first order kinetic for the uptake of the 1,4-dihypyridine derivatives by T. cruzi epimastigotes was found. Thus, nicardipine, the most potent derivative, exhibited the highest apparent rate constant, ku, (0.043 min-1). On the other hand, no susceptibility differences by strains and clone Dm 28c to the action of these drugs were found. PMID- 9366043 TI - The amiloride-sensitive Na+ channel: from primary structure to function. AB - Three homologous subunits of the amiloride-sensitive Na+ channel, entitled alpha, beta, and gamma, have been cloned either from distal colon of a steroid-treated rat or from human lung. The alpha, beta, and gamma subunits have similarities with degenerins, a family of proteins found in the mechanosensory neurons of the nematode Caenorhabditis elegans. All these proteins are characterized by the presence of a large extracellular domain, located between two transmembrane alpha helices, and by short NH2 and COOH terminal cytoplasmic segments. They constitute the first members of a new gene super-family of ionic channels. The epithelial Na+ channel is specifically expressed at the apical membrane of Na(+)-reabsorbing epithelial cells. Its activity is controlled by several distinct hormones, especially by corticosteroids. These hormones act either transcriptionally (such as aldosterone in distal colon, or glucocorticoids in lung) and/or post transcriptionally (such as aldosterone in kidney). Recent works have provided new insights in the function of that important osmoregulatory system. PMID- 9366044 TI - An aldosterone regulated chicken intestine protein with high affinity to amiloride. AB - The pattern of chicken intestine amiloride-binding proteins was determined using the photoreactive amiloride analogue 2'-methoxy-5'-nitrobenzamil (NMBA) and a polyclonal anti-amiloride antibody. At 10(-7)M, NMBA inhibits approximately 62% of the Na+ channel activity. At this concentration the amiloride analogue labels a number of membrane proteins, and in particular a 40-45 kDa polypeptide denoted ABP40. Incorporation of NMBA into ABP40 could be prevented by a 100-fold excess of benzamil, but not by a 1000-fold excess of 5-(N-ethyl-N-isopropyl)-amiloride. Labeling of ABP40 was intense in membranes derived from salt-deprived chickens and approximately 5-fold weaker in membranes from salt-repleted animals. Because of its small size, ABP40 is not likely to be an avian Na+ channel subunit, yet this amiloride-binding protein could be involved in the response to aldosterone. PMID- 9366045 TI - Ontogeny of Na+ transport in rat colon. AB - To obtain information about whether nutrient and hormonal factors are critical for the developmental pattern of electrogenic amiloride-sensitive Na+ transport (NaSCC) in rat distal colon, we studied the effect of adrenalectomy, high dietary Na+ intake, and hypothyroidism on colonic NaSCC in weanling rats. Adrenalectomy and high dietary Na+ intake inhibited NaSCC, decreased plasma level of aldosterone, and did not influence plasma level of thyroxine. Hypothyroidism inhibited NaSCC without significant changes of plasma aldosterone. These results suggest that the high activity of NaSCC during weaning period reflects the relatively low Na+ intake, and that thyroid hormones have an important permissive role in the developmental changes of NaSCC. PMID- 9366046 TI - Comparative aspects of actions of a short-chain phospholipid on epithelial Na+ channels and tight junction conductance. AB - Ion transport in both the frog skin (a high-resistance epithelium) and the rabbit nasal airway epithelium (a low-resistance epithelium) are dominated by electrogenic Na+ absorption via apical membrane amiloride-sensitive Na+ channels, and short-circuit current (ISC) is essentially a measure of Na+ absorption in both epithelia. In both epithelia, mucosal application of the short-chain phospholipid didecanoyl-L-alpha-phosphatidylcholine (DDPC) dose-dependently inhibited the amiloride-sensitive ISC and caused an initial decrease in epithelial conductance (Gt) followed by an increase in Gt to steady-state values above control level. The effects were reversible. It is concluded that DDPC (a) inhibits epithelial amiloride-sensitive Na+ channels and (b) induces an increase in paracellular tight junction conductance. These effects may involve changes in non-specific lipid-protein interactions at the cell membrane level. PMID- 9366047 TI - Regulation of Ca(2+)-activated K+ channels from rabbit distal colon. AB - Transepithelial transport in the rabbit distal colon surface cells involves the integrated function of amiloride-sensitive Na+ channels in the luminal membrane and the Na, K-pump, together with K+ channels in the basolateral membrane. Incorporation of plasma membrane vesicles from surface cells into planar lipid bilayers shows that a Ca(2+)-activated maxi K+ channel with a single channel conductance of approximately 275 pS is predominant in the basolateral membrane of this cell type. The epithelial Ca(2+)-activated maxi K+ channels are regulated by Ca2+ in the intracellular range of concentration, pH, and membrane potential. The high Ca(2+)-sensitivity of the epithelial maxi K+ channels is dependent on the channel protein being in a phosphorylated state. Dephosphorylated channels can regain their Ca(2+)-sensitivity after phosphorylation catalyzed by a cAMP dependent protein kinase. The extensive regulation of the epithelial maxi K+ channels by intracellular factors suggests that these channels may play an important role in regulation of transepithelial transport and may be one explanation for the apparent tissue to tissue variability in properties for this channel type. PMID- 9366048 TI - Na/D-glucose cotransport and SGLT1 expression in hen colon correlates with dietary Na+. AB - We have tested whether separately varying the content of either Na or Cl in diets causes earlier observed increase in Na-coupled sugar and amino acid transport induced by high NaCl diets in hen colon. A comparison was also made between the dependence of the Na-coupled transport on a pure wheat/barley/soya diet against a diet with supplements of essential amino acids, fatty acids, vitamins, and trace elements, as a test for possible elimination of the cotransporters due to a deficient diet. Na/nutrient-coupled transport was measured as changes in short circuit current. The level of expressed Na/glucose cotransporters, SGLT1, due to dietary alterations was followed by quantitative Western blot and immunodetection of SGLT1 in colon, and the dietary effects on plasma aldosterone were assessed as well. An observed switch in transport from amiloride-sensitive electrodiffusive Na transport to phlorizin-sensitive Na/D-glucose cotransport and Na/amino acid coupled transport is caused solely by increasing Na+ in the diet. Thus, neither dietary Cl- nor the dietary supplements altered the expression of Na(+)-coupled nutrient transport processes. Corroborating these findings, only Na+ in the diet increased the expression of SGLT1 in colon epithelium and suppressed aldosterone level in plasma. PMID- 9366049 TI - Comparative aspects of chloride-dependent amino acid transport across the brush border membrane of mammalian small intestine. AB - Chloride-dependent amino acid transport has been described in several tissues. This article briefly reviews the evidence of cotransport of chloride and amino acids across the brush-border membrane of rabbit distal ileum. On the basis of amino acid carriers described in the rabbit and the surveys of chloride dependence reported, a comparison of amino acid carriers in the mammalian small intestine is performed. Additional characteristics of the carriers in the different species are included in the discussion when necessary. From this comparison the rabbit distal ileum and the pig small intestine emerge as the best models of amino acid transport in the human small intestine. PMID- 9366050 TI - Effect of mucosal amino acids on SCC and Na and Cl fluxes in the porcine small intestine. AB - Most amino acids are, like glucose, co-transported with sodium and are thereby potential additives to oral rehydration solutions for the treatment of diarrhea. In this study the effects of mucosal amino acids on short-circuit current and Na and Cl fluxes in three segments of the porcine small intestine were studied. L alanine, L-leucine, L-lysine, L-proline, L-phenylalanine and L-glutamine were added (chamber concentration of each amino acid was 20 mmol x l-1) to the mucosal side of stripped proximal, mid, and distal small intestine sheets mounted in Ussing chambers in glucose containing (16 mmol x l-1) bathing medium; electrical parameters and unidirectional fluxes were measured. The amino acids induced a significant elevation in mucosa to serosa flux and unaltered serosa to mucosa flux of Na in all three segments, resulting in significant elevation in net Na absorption in proximal (2.4 +/- 0.3 microEq x cm-2 x hr-1 to 3.5 +/- 0.3 microEq x cm-2 x hr-1, P < 0.05), mid (5.9 +/- 0.5 microEq x cm-2 x hr-1 to 8.1 +/- 0.7 microEq x cm-2 x hr-1, P < 0.05) and distal (5.9 +/- 0.6 microEq x cm-2 x hr-1 to 8.3 +/- 0.7 microEq x cm-2 x hr-1, P < 0.05) small intestine. The mucosa to serosa Cl flux was significantly elevated in all three segments (P < 0.01) by amino acids abolishing the net Cl secretion in proximal (2.5 +/- 0.4 microEq x cm 2 x hr-1 to 0.8 +/- 0.6 microEq x cm-2 x hr-1, P < 0.01) and mid (2.2 +/- 0.4 microEq x cm-2 x hr-1 to 0.1 +/- 0.9 microEq x cm-2 x hr-1, P < 0.01) small intestine. The changes in SCC were carried by the electrogen Na absorption. In conclusion, the amino acids, in addition to glucose, stimulate Na absorption by about 1.0 microEq x cm-2 x hr-1 in the proximal part, and 2.5 microEq x cm-2 x hr 1 in the mid and distal part of the small intestine. PMID- 9366051 TI - Correlation of structure and function in the chicken lower intestine (coprodeum): a review. PMID- 9366052 TI - Aldosterone and the control of lower intestinal Na+ absorption and Cl- secretion in chickens. AB - There are several ion-transport systems expressed in the lower intestinal segments of chickens, depending on the level of the salt intake. The aim of this study was to test the hypothesis that aldosterone is the sole regulator of all these ion-transport systems, as had been indicated by our previous results. Chickens were long-term adapted to low salt intake, and then switched to a high salt diet. During the first 5 days of resalination, the birds were injected with aldosterone every 8 hr and then the magnitude and characteristics of the epithelial ion-transport systems in colon and coprodeum were investigated. The results support strongly the hypothesis that aldosterone exerts major control of the amiloride-inhibitable Na(+)-transport system in both colon and coprodeum, as its magnitude was maintained high in spite of the resalination process. Spironolactone counteracted the actions of aldosterone, although not totally. On the other hand, aldosterone is not the sole regulator of the hexose/aminoacid-Na+ cotransport systems in colon, although it can act as their modulator, as the injections did delay the normal increase always seen in these transport systems during resalination. Aldosterone can also modulate the Cl(-)-secretory capacity of colon and coprodeum, but only temporarily. PMID- 9366053 TI - Transport characteristics of the colonic epithelium of the Japanese quail (Coturnix coturnix). AB - The colon of the domestic fowl sustains a reabsorptive Na+ current on both high- and low-sodium diets. However, there is a marked shift in the apical transport step under these two extreme conditions, from amino acid/hexose cotransport on high-salt diets to amiloride-sensitive Na+ channels on low-salt diets. The present experiments were performed to study colonic Na+ transport in another galliform species, the Japanese quail (Coturnix coturnix). Birds were maintained on a commercial game feed containing 0.18% Na+ (78 mumoles/g), an intermediate level of salt intake. Experiments were performed on unstripped colons in standard Ussing chambers with bicarbonate/CO2 buffer solution on both sides. Baseline values (n = 11) for PD (3.13 +/- 0.68 mV) and short circuit current (SCC, 30.87 +/- 7.79 microA/cm2) were lower than those reported for chickens on a similar diet, whereas tissue resistance (76.06 +/- 4.19 omega.cm2) was similar. Addition of amino acids (4 mM leucine + lysine) increased SCC by 10.85 +/- 1.97 microA/cm2. Both phloridzin (1 mM) and amiloride (10(-5) M) decreased SCC, by 7.05 +/- 1.26 and 9.64 +/- 2.68 microA/cm2, respectively. Thus, on this diet the quail colonic epithelium maintains both amino acid/hexose cotransporter activity and amiloride sensitive channel activity. Arginine vasotocin (10(-6) M) caused a small, but consistent decrease in SCC, while acetazolamide increased SCC. Aldosterone (128 micrograms/kg), given 4 hr prior to the experiment (n = 4) significantly reduced the amino acid stimulated SCC. These results confirm, for the Japanese quail, the presence of multiple apical Na+ entry mechanisms in colonic epithelium. Amino acid cotransporter activity, in particular, appears to be highly sensitive to aldosterone suppression. PMID- 9366054 TI - Novel transport properties of colonic crypt cells: fluid absorption and Cl dependent Na-H exchange. AB - Colonic ion transport is heterogeneous including the long-accepted spatial separation of absorptive and secretory processes between surface and crypt cells. We recently described the isolation of individual crypts from the rat distal colon that were studied using microperfusion technology. Na-dependent fluid absorption was consistently demonstrated in these crypts during perfusion with a Ringer-like solution; dibutyryl cyclic AMP, VIP and acetylcholine, when added to the bath solution, all induced net fluid secretion. As several morphologic techniques, including immunocytochemistry, failed to provide evidence for the presence of myofibroblasts in the isolated crypt preparation, we propose that a Na-dependent absorptive process is a constitutive transport mechanism in crypt cells, while secretory processes are regulated by the release of one or more neurohumoral agonists from lamina propria cells including myofibroblasts. The mechanism of Na-dependent fluid movement was also studied by determining [H] gradient stimulation of 22Na uptake in isolated apical membrane vesicles (AMV) from crypt cells. In contrast to Na-H exchange in surface cell AMV, Na-H exchange in crypt cells is Cl-dependent. Intracellular pH determined in crypt cells using video-imaging fluorescence microscopy established that the response to an acid load requires both lumen Na and Cl. As a result, these studies have identified a novel Cl-dependent Na-H exchange in crypt AMV that may mediate apical membrane Na uptake and regulate pHi. PMID- 9366055 TI - The role of K+ channels in colonic Cl- secretion. AB - Cl- secretion in the rat colonic crypt base cell (bc) requires the coordinated (a) opening of Cl- channels in the luminal membrane; (b) activation of the Na+2Cl K+ cotransporter; (c) enhanced conductive K+ exit from the cell; and (d) increased pumping by the (Na+ + K+)-ATPase. In this study we focus on the importance of conductive K+ exit. After stimulation with the cholinergic agonist carbachol (CCH, 0.1-10 mumol/l) bc respond with a marked increase in whole cell (wc) conductance and a hyperpolarization of the membrane voltage (Vm). This is paralleled by a marked increase in the (Cl- secretory) short-circuit current (Isc) in Ussing chamber studies of the intact distal colon. Current evidence favors the view that CCH, via IP3, enhances cytosolic Ca2+ activity, and that Ca2+ increases the open probability of Cl- channels indirectly and that of K+ channels directly. After stimulation with PGE2 bc also enhance the wc conductance, but this is paralleled by a marked depolarization of Vm. Again these effects correspond to a marked increase in (Cl- secretory) Isc. The depolarization and enhanced wc conductance is partly due to the activation of Cl- channels. However, current evidence suggests that these effects on Cl- channels are paralleled by an activation of K+ channels. The chromanol 293B, by inhibiting these K+ channels specifically, abolishes PGE2-induced Cl- secretion completely, but has no effect on basal K+ conductance or on CCH-induced Cl- secretion. CCH apparently activates a Ca(2+)-dependent K+ channel with a conductance of 10-20 pS, whilst PGE2 (or cAMP) activate a much smaller K+ channel. Only the latter K+ channel can be inhibited by 293B in excised patches. Noise analysis suggests that this K+ channel has a conductance of < 3 pS and fast kinetics. The complete 293B induced inhibition of Cl- secretion caused by PGE2 can be explained by the fact that PGE2 induces a marked depolarization and that this depolarization reduces the basal K+ conductance. Current evidence suggests that this inhibition of the basal K+ conductance is caused by a depolarization induced inhibition of Ca2+ entry. PMID- 9366057 TI - Signal transduction pathways for serotonin as an intestinal secretagogue. AB - This review presents a signal transduction pathways for serotonin (5 hydroxytryptamine, 5-HT) as an intestinal secretagogue and some recently published related findings. 5-HT is a secretagogue in the small and large intestine of all studied species including pig and man. 5-HT mediates intestinal secretion through activation of at least the epithelial 5-HT2, and neuronal 5 HT3, and 5-HT4 receptors in the submucosal plexus, including a reflex arc. 5-HT activates both a cholinergic and a non-cholinergic pathway in its secretory response. Intracellular mediators include at least eicosanoids (prostaglandin E2), calcium, phosphoinositols (1,4,5-inositol trisphosphate) and maybe nitric oxide and cyclic nucleotides. Pig small intestine appears to be an appropriate model for the human small intestine with respect to the signal transduction pathways for 5-HT as an intestinal secretagogue. Species and segmental differences in the signal transduction pathways for 5-HT as an intestinal secretagogues are discussed together with related news on 5-HT receptors, 5-HT antagonists in clinical use, the enteric nervous system, and intracellular mediators. PMID- 9366056 TI - Ion transport across the murine intestine in the absence and presence of CFTR. AB - CF mice, i.e., mice without functional CFTR (cystic fibrosis transmembrane conductance regulator) exhibit a very low basal Isc in all regions of the intestinal tract. The low basal Isc in the intestinal epithelia of the CF mice appears to be a result of lack of spontaneous Cl- secretion (and possibly HCO3- secretion) mediated by neurotransmitter release from the enteric nervous system. In contrast to intestinal epithelia from normal mice, the intestinal epithelia of CF mice do not secrete Cl- in response to agents that increase cAMP (forskolin). Furthermore, as in human CF patients, agents that increase intracellular Ca2+ (bethanacol, ionomycin) failed to elicit Cl- secretion in the intestinal epithelia of CF mice. There was no difference in the electrogenic Na(+)-coupled glucose absorption in the CF murine jejuna compared to jejuna from normal mice. However, further studies are warranted to determine whether amiloride-sensitive Na+ absorption is upregulated in the murine CF colon. It was concluded that the intestinal epithelium of the CF mouse model exhibits some striking similarities to its human counterpart, and therefore should be very useful in further characterizing the ion transport defects in this disease. PMID- 9366058 TI - Stimulation of three distinct guanylate cyclases induces mucosal surface alkalinisation in rat small intestine in vitro. AB - The absorptive surface of the small intestine is isolated from bulk pH changes in the luminal contents by a zone of maintained low pH, the acid microclimate. The present study set out to compare the effects of stimulation of each of the three guanylate cyclases (GCs) expressed in the intestinal mucosa on the pH microclimate of rat jejunum in vitro. The tissue was exposed to specific ligands for each of the GCs and mucosal surface pH determinations were made by a miniaturised glass pH electrode. The ligands used were E. coli STa enterotoxin, atrial natriuretic peptide (ANP) and nitric oxide (NO, via the donor sodium nitroprusside (SNP)). Challenge from all three agonists resulted in significant alkalinisation of the jejunal mucosa. The actions of SNP were blocked by the soluble GC inhibitor, methylene blue (MB) whereas those of STa were unaffected by MB. The data are consistent with previous observations that cGMP-induced inhibition of brush border Na+/H+ exchange results in elevation of mucosal surface pH. We conclude that all three of the identified GC pathways in the intestinal mucosa are capable of contributing to the control of mucosal acidification in the upper small intestine. PMID- 9366059 TI - Effect of ondansetron on Salmonella typhimurium-induced net fluid accumulation in the pig jejunum in vivo. AB - Two major pathophysiological mechanisms explaining the diarrhoea induced by Salmonella typhimurium have been suggested to be: (a) invasion of the intestine by the bacteria, and (b) an enterotoxin resembling Vibrio cholerae toxin. Cholera toxin is a potent secretagogue in pig small intestine and induces secretion partly by activating 5-hydroxytryptamine receptors, following release of 5 hydroxytryptamine. Ondansetron is a selective 5-hydroxytryptamine-3 receptor antagonist, which reduces the cholera toxin-evoked fluid accumulation in pig jejunum. The aim of this study was to investigate the effect of ondansetron on Salmonella typhimurium-induced fluid accumulation in ligated loops of pig jejunum in vivo. 10(10) colony-forming units of the bacteria was injected into loops and incubated for 8 hr. 200 mg x kg-1 ondansetron given subcutaneously reduced the Salmonella typhimurium-induced fluid accumulation by about 40%. This results suggests the involvement of 5-hydroxytryptamine and 5-hydroxytryptamine-3 receptors in Salmonella typhimurium-induced diarrhoea. PMID- 9366060 TI - The effect of histamine on ion transport in porcine jejunum. AB - Histamine is present in the gastrointestinal tract, and is an important mediator in gastrointestinal type I hypersensitivity reactions. The effect of histamine on ion transport in "stripped" porcine jejunal preparations was investigated. Histamine caused a transient increase in short-circuit current (SCC), which seemed to be concentration dependent. A maximum response was obtained at 0.1 mM. The histamine response was attenuated (44.8%) by the neuronal conduction blocker, tetrodotoxin (TTX), indicating that enteric neurotransmitters are involved. The neurokinin-1 antagonist, CP 99,994, did not alter the response to histamine (0.1 mM). Thus, tachykinins acting at NK-1 receptors do not seem to be involved in the histamine response. PMID- 9366061 TI - The effect of alpha-trinositol on cholera toxin-induced fluid accumulation in pig (Sus scrofa domesticus) jejunum in vivo. AB - The effect of alpha-trinositol (D-myo-inositol-1,2,6-trisphosphate) on cholera toxin-induced fluid accumulation (i.e., net fluid secretion) was studied in the pig jejunum in vivo. Cholera toxin caused a dose-dependent fluid accumulation in control experiments. Intravenous injection of alpha-trinositol produced a reduction of the response to cholera toxin with a significant maximal inhibition of 36%. However, in high concentrations of alpha-trinositol this inhibition was absent. PMID- 9366062 TI - Regulation of ion transport in the porcine intestinal tract by enteric neurotransmitters and hormones. AB - In the present paper, the mechanisms underlying the neural and hormonal regulation of mucosal ion transport in the pig intestinal tract are reviewed. The active transport of NaCl by isolated sheets of porcine intestinal mucosa is modulated by cholinergic and non-cholinergic neurons of undetermined neurochemical identity that lie in the submucosa. The application of electrical field stimulation to mucosa-submucosa preparations from porcine jejunum, ileum, or colon produces rapid elevations in short-circuit current which are inhibited by tetrodotoxin or omega-conotoxin GVIA, blockers of neuronal Na+ and Ca2+ channels, respectively. In porcine ileum, these elevations in current are mimicked in large part by cholinergic agonists and have been attributed to anion secretion. The majority of classical neurotransmitters and gut peptides that have been examined to date increase active transepithelial anion secretion through interactions with G protein-coupled receptors associated with submucosal neurons or situated on the basolateral membranes of epithelial cells. A small number of neuropeptides interact with neuronal receptors to augment NaCl absorption or decrease anion secretion. Noradrenergic control of intestinal transport differs in the porcine small and large intestines, and displays considerable inter species variability in its cellular underpinnings. Transport regulation by bombesin-like peptides may be mediated by receptors distributed in both the apical and basolateral membrane domains of epithelial cells in porcine colon. The transport process affected by these peptides may be linked to epithelial growth and differentiation. The pig intestinal tract appears to be a useful biological model for resolving the cellular mechanisms by which gut neurotransmitters and hormones act in regulating transepithelial ion fluxes. Its general relevance to human intestinal function is discussed. PMID- 9366063 TI - The enteric nervous system and cholera toxin-induced secretion. AB - This article reviews briefly some general aspects of the enteric nervous system (ENS). Furthermore, the ENS control of epithelial transport is exemplified by a description of the enteric nervous reflexes activated by cholera toxin. PMID- 9366064 TI - Electrophysiology of neurochemically identified submucosal neurones of the guinea pig intestine. AB - A number of electrophysiological studies have shown that neurones in the submucous plexus are endowed with three major types of synaptic potentials in response to nerve stimulation: a fast EPSP, a slow IPSP, and a slow EPSP. Combined electrophysiological and immunohistochemical studies enabled analysis of the types of neurochemically identified neurones which receive each type of synaptic input. This short review briefly summarizes the results obtained from these studies. PMID- 9366065 TI - Structural organization and neuropeptide distribution in the mammalian enteric nervous system, with special attention to those components involved in mucosal reflexes. AB - Gastrointestinal events such as peristalsis and secretion/absorption processes are influenced by the enteric nervous system, which is capable of acting largely independently from other parts of the nervous system. Several approaches have been used to further our understanding of the underlying mechanisms of specific enteric microcircuits. Apart from pharmacological and physiological studies, the deciphering of the chemical coding of distinct morphological and functional enteric neuron classes, together with a detailed analysis of their projections by the application of immunocytochemistry, of tracing, and of denervation techniques, have substantially contributed to our knowledge. In view of existing interspecies and regional differences, it is of major importance to expand our knowledge of the enteric nervous system in mammals other than the guinea-pig, the most commonly used experimental animal in this research area. This will increase our chances of finding a valid model, from which well-founded extrapolations can be made regarding the precise function of distinct enteric neuron types regulating motility and ion transport in the human gastrointestinal tract. PMID- 9366066 TI - Differential effects of inflammatory mediators on ion secretion in the guinea-pig colon. AB - Bi-directional interactions between the enteric nervous system and the immune system play an important role in gut inflammation. We therefore investigated the effects of the inflammatory mediators, prostaglandin (PGD2, PGE2, PGI2, and PGF2 alpha) and leukotriene (LTC4), on guinea-pig colonic secretion and on electrophysiological behaviour of submucosal neurones. In Ussing chambers, all inflammatory mediators evoked a dose-dependent increase in short circuit current (Isc) that represented electrogenic chloride secretion. The secretory response was significantly reduced by tetrodotoxin (TTX) and atropine suggesting involvement of cholinergic submucosal neurones. Long-term application of prostaglandins and LTC4 induced TTX- and atropine-sensitive cyclical chloride secretions. Intracellular recordings revealed activation of submucosal neurones by all inflammatory mediators. This activation consisted of depolarisation of the membrane associated with increased spike discharge. Frequently, prostaglandins and LTC4 induced spontaneous occurrence of cholinergic fast excitatory postsynaptic potentials. Results suggest that the role of the enteric nervous system in neuroimmune interactions consists of a potentiation of the direct epithelial effect of inflammatory mediators by the activation of submucosal neurones. Ongoing nerve-mediated cyclical changes in chloride secretion may be interpreted as the induction of intrinsic alarm programs. The effects of inflammatory mediators may serve as a defense mechanism to dilute noxious substances in the lumen. PMID- 9366067 TI - Electro- and transportphysiological changes in pig proximal colon during parasitic infection. AB - Oesophagostomum dentatum, one of the most common nematodes in pigs, causes the formation of subepithelial granuloma in the large intestine. To investigate possible changes in epithelial function or response during the infection we incubated epithelia of pig proximal colon in Ussing chambers at different days post infectionem (p.i.). Transepithelial conductance, gt, and the Cl flux from serosal to mucosal, JsmCl, were increased on day 2 p.i., when the nematodes penetrate the epithelium of the large intestine, and declined toward control levels thereafter. Histamine, PGE2 and carbachol caused transient increases in short circuit current, Isc, and conductance that could partly be attributed to a higher JsmCl. The Isc responses were highest on the days of nematode penetration in or out of the epithelium (days 2 and 14 p.i.) and did decline on day 7 p.i. during the histotropic development of the parasite. This reduced epithelial reaction on day 7 p.i. might be an adaptation to secretory stimuli released from the inflammatory cells in the intestinal wall or might reflect modulation by the parasite and could be responsible for the absence of marked clinical signs during the infection. PMID- 9366068 TI - Differential response of legumes and creep feeding on gut morphology and faecal composition in weanling pigs. AB - The effects of creep feeding and different levels of soybean meal (SBM) and cowpea meal on the intestinal morphology and faecal characteristics were investigated in weaners. Prior to the feeding trial, one group of piglets was creep-fed and the other noncreep-fed. The two groups of piglets were weaned at 28 days and randomly assigned to four different diets, the main protein sources of which were: T1--skimmed milk power (control); T2--31% soybean meal (high SBM), T3 -15% soybean meal and 12% skimmed milk powder (low SBM), and T4--100% raw cowpea meal. Live weight gain was highest in the control group, and least in cowpea-fed piglets. At weaning, only the noncreep-fed weaners showed villus atrophy and crypt hyperplasia but at 7 days postweaning, these changes were evident in all groups except the control and were more severe in the noncreep SBM and cowpea-fed groups. At 21 days postweaning, only noncreep cowpea-fed pigs showed a reduced villus height when compared to the control group. A mild diarrhoea was generally observed in all noncreep-fed weaners, but its onset was more rapid (P < 0.01) and the duration much longer (P < 0.05) in the high SBM and cowpea-fed pigs than in low SBM and control groups. A lower faecal pH was observed in weaners that had diarrhoea when compared with a pH of 7.1 in pigs with normal faecal moisture. The observations of enteropathology and low growth performance in the cowpea group suggest that feeding raw cowpea to weaners may induce antigenicity in the intestinal mucosa, causing damage and a consequent decrease in productivity. However, the introduction of creep feeding before weaning appears to have some ameliorative effects. PMID- 9366069 TI - Synaptic communication between external and internal submucosal plexus neurones in the jejunum of the newborn pig? AB - Intracellular recordings were made from neurones in the internal submucosal plexus (ISP) of porcine small intestine and synaptic inputs were investigated by focal stimulation of nerve fiber tracts. Nicotinic fast excitatory potentials (e.p.s.p.s) were recorded in all neurones, but slow e.p.s.p.s and slow inhibitory potentials (i.p.s.p.s) were rarely seen. Membrane potential changes similar to those occurring during the slow e.p.s.p. and slow i.p.s.p. could be evoked by exogenous application of neurotransmitters, even in neurones failing to display a nerve-mediated response. We suggest that the predominant source of the slow synaptic inputs to the ISP may be the neurones of the external submucosal plexus (ESP). The failure to record slow e.p.s.p.s and i.p.s.p.s could be a consequence of the anatomical arrangement of the submucosal plexuses whereby interconnecting strands between the ISP and ESP are inaccessible to the focal stimulation. PMID- 9366070 TI - Birth and prematurity influence intestinal function in the newborn pig. AB - Developmental changes in intestinal function occur in the perinatal period of many species. We investigated the hypothesis that gestational age at delivery and the mode of delivery influence intestinal function. Newborn pigs (106-108 or 113 115 days gestation, term = 115 +/- 2 days) were either delivered by caesarean section or born vaginally following induction of parturition with a prostaglandin F2 alpha analogue. The pigs were killed at birth and used for measurements of intestinal ion transport in vitro (using Ussing chambers) or killed at 2 days of age, after being fed porcine colostrum to follow the absorption of intact proteins into plasma. The results indicate that premature birth is associated with increased paracellular permeability to ions. The uptake and net absorption of chloride were higher in the term, vaginally-delivered pigs than in the remaining pigs. Among the newborn pigs, the preterm caesarean-delivered pigs exhibited the lowest chloride secretion in response to the secretagogue, theophylline. The latter pigs also absorbed the lowest amounts of immunoglobulin G and albumin from colostrum. In conclusion, gestational age at delivery and the mode of delivery have significant effects on intestinal transport of ions and intact proteins. However, the observed variation in the magnitude and the direction of responses indicate that (a) prematurity and birth influence the transport of ions and intact proteins through independent regulatory mechanisms and (b) the absorption pathways for ions and intact proteins in the neonatal pig intestine are not closely associated. PMID- 9366071 TI - Electrophysiological classification of submucosal plexus neurones in the jejunum of the newborn pig. AB - Intracellular recordings were made from the internal and external submucosal ganglia of the porcine small intestine and neuronal properties were classified using two existing schemes for guinea-pig enteric neurones. In the first analysis, 77% of cells were designated as Type 4 since they were a heterogeneous population of neurones with the overlapping properties of S/Type 1 and AH/Type 2. The simplicity and usefulness of the second classification scheme was due to its emphasis on a single electrophysiological event, namely, the long-lasting after hyperpolarization (AH) following the action potential. Eighty-eight percent of the cells studied were thus categorized as either AH (with an AH) or S (without an AH). All S neurones displayed fast synaptic potentials in response to stimulation of interganglionic fibre strands. AH neurones were subdivided into two groups dependent on whether they received fast synaptic inputs. Only by employing the second scheme of classification were differences in the neuronal characteristics and synaptic profiles between the two submucosal plexuses detected. It is concluded that the S and AH system of classification is the most appropriate method for the analysis of intracellular recordings from submucosal neurones in the porcine small intestine. PMID- 9366072 TI - SCFA transport in the forestomach of ruminants. AB - Short-chain fatty acids are the main end-products of microbial metabolism in the forestomach of ruminants. SCFA produced by the microorganisms are rapidly absorbed across forestomach epithelia and can cover up to 80% of the energy requirement of the animal. Although there is a great concentration gradient for SCFA between the forestomach content and the blood favoring passive transport, (secondary) active transport mechanisms are likely involved in SCFA permeation across the epithelia. (Secondary) active SCFA transport seems to be mediated by an anionic exchange system. The system interacts with other anions like chloride and bicarbonate. Similar to the large intestine of various species, SCFA can stimulate sodium transport probably by activating a Na+/H+ exchange located in the apical membrane. However, in contrast to the large intestine, SCFA transport itself seems to be independent from sodium. Part of the absorbed SCFA does not reach the blood side in the original form because it is metabolized in the epithelial cell. Metabolism, in turn, influences SCFA transport. PMID- 9366073 TI - Effects of short-chain fatty acids on cell volume regulation and chloride transport in the rat distal colon. AB - Superfusion of isolated crypts from rat colon with sodium butyrate-containing solutions induced an amiloride-sensitive swelling of the cells at the upper one third of the crypt. In HCO3(-)-containing buffer, swelling was followed by regulatory volume decrease, which was inhibited by K+ and C- channel blockers and inhibitors of leukotriene synthesis. Whole-cell patch-clamp recordings revealed that butyrate induced a membrane depolarization, which was dependent on Cl- and was accompanied by an increase in membrane inward current, indicating an increase in Cl- conductance. Membrane outward (K+) current, however, behaved inconsistently, suggesting an activation of swelling-induced K+ currents, but an inhibition of pH-sensitive K+ currents due to the cellular acidification. Cell attached patch-clamp recordings showed an activation of basolateral Cl- channels by butyrate. The lipoxygenase inhibitor, NDGA (nordihydroguaiaretic acid), inhibited the butyrate response and even reversed it into a slight hyperpolarization indicating that the butyrate-induced Cl- channels, but not the K+ channels, are stimulated by a leukotriene. Short-chain fatty acids concentration-dependently decreased short-circuit current (Isc). The decrease in Isc was diminished by a Cl- channel blocker, NPPB (5-nitro-2-[3 phenylpropylamino]-benzoate), and a lipoxygenase inhibitor, NDGA. Butyrate stimulated the mucosa to serosa fluxes (Jms) of Na+ and Cl-. The effect on J(ms)Cl was blocked by NPPB or NDGA. The stimulation of J(ms)Cl correlated with the degree of metabolism of the short-chain fatty acid. Consequently, two factors seem to be responsible for the stimulation of Cl- absorption by short-chain fatty acids: (a) the intracellular production of HCO3- during the oxidation of short chain fatty acids as substrate for the apical Cl-/HCO3- exchanger, and (b) the activation of volume-sensitive basolateral Cl- channels. PMID- 9366074 TI - SCFA and electrolyte absorption in the colon of three rodent species. AB - The effects of nutritional regime on the colonic absorption of electrolytes, water, and short-chain fatty acids (SCFA) were studied in three rodent species (voles, spiny mice, and laboratory mice) differing in their ecological background. The effects of different levels of SCFA, induced by restriction of food intake, on the capacity of the in situ perfused colon to absorb water and electrolytes was studied. In addition, in vitro experiments were carried out to assess the mechanisms related to electrolyte transport in the proximal and distal colon. Water and solutes absorption from the perfused colon in the food restricted voles were significantly lower compared to voles fed ad libitum. No such effect was recorded in the two murid species. In vitro studies, employing Ussing chambers, were conducted to characterize the sodium and chloride transport mechanisms. In the colon of the voles and spiny mice as well as in the distal colon of the laboratory mice, net Na+ flux was not significantly different from that of Cl-, and both were higher than the measured equivalent short circuit current. The results suggest an electroneutral sodium transport mechanism in all three species. A high capacity to adjust the rate of water absorption to the amount of fermentable substance in the intestine was demonstrated only in the vole. PMID- 9366075 TI - Feed-induced changes in transport across the rumen epithelium. AB - The effect of feeding strategy on rumen epithelial growth and transport capacity were studied in sixteen dairy cows. There was a significant effect of feeding strategy on transport of butyrate, sodium and chloride ions, which could not be explained by changes in epithelial surface area, structure or resistance. PMID- 9366076 TI - Absorption and fate of L- and D-lactic acid in ruminants. AB - Lactic acid is produced in significant amounts in the rumen on rations rich in easily digestible carbohydrates such as starch and sugars. If high amounts of concentrates, containing starch and sugars, are fed to high lactating dairy cows, lactic acid concentrations in rumen fluid up to 80 mmol/l can be found. If such high concentrations of lactic acid are consistent during longer periods of time, rumen acidosis may arise, causing disfunction and necrosis of rumen epithelium. PMID- 9366077 TI - Transepithelial SCFA gradients regulate polarized Na/H exchangers and pH microdomains in colonic epithelia. AB - Short chain fatty acids (SCFAs) stimulate electroneutral sodium absorption by activation of apical Na/H exchange in colonocytes. It is often assumed that activation of Na/H exchange is via an intracellular acidification caused by SCFA uptake. These lecture notes review shortcomings in this model of SCFA-stimulated sodium absorption, revealed by recent reports in the literature. This is supplemented by information generated in our laboratory using both a tissue culture model of colonocytes (HT29-C1 cells) and a native tissue preparation (mouse distal colonic mucosa). In both preparations, evidence suggests that physiologic SCFA gradients may generate pH heterogeneity in aqueous microdomains near the plasma membrane of colonocytes. Finally, direct observation of such extracellular microdomains with confocal microscopy is used to support a new model, in which pH microdomains play an important role in regulating both SCFA fluxes and sodium absorption. PMID- 9366079 TI - In vitro studies on transport and metabolism of short-chain fatty acids in pig hindgut. AB - An analytical method based on alkaline freeze drying, ultracentrifugation, and quantitative gas chromatography was established to differentiate between mucosal uptake, tissue accumulation, and serosal release of SCFA in pig hindgut. It was shown that serosal release of SCFA was substantially lower than mucosal uptake and tissue accumulation, indicating substantial degradation and/or metabolism during transepithelial movement. PMID- 9366078 TI - Effect of SCFA on intracellular pH and intracellular pH regulation of guinea-pig caecal and colonic enterocytes and of HT29-19a monolayers. AB - The response of the intracellular pH (pHi, measured with BCECF) of the caecal and distal colonic epithelium of guinea pig and of monolayers of HT29 clone 19a cells on the addition of short-chain fatty acids (SCFA) was assessed. Addition of SCFA to the luminal side of these cells had no major effect on pHi, independent of whether the apical Na+/H+ exchange or the apical K+/H+ ATPase was inhibited or not. Addition of SCFA to the serosal side, on the other hand, caused a marked decrease of pHi, followed by an effective regulation back to basal values, and after removal of the acid, the cells became alkalinized. Intracellular pH is mainly regulated by mechanisms in the basolateral membrane. The basolateral Na+/H+ exchanger and the Cl-/HCO3- exchanger were mainly responsible for pHi regulation. Inhibition studies are consistent with a NHE-1 type Na+/H+ exchanger in the basolateral membranes. The apical Na+/H+ exchanger of caecal enterocytes and in HT29 cells, and the apical K+/H+ ATPase in the apical membrane of the distal colon have no or little influence on pHi regulation. The comparison shows that the HT29-19a cell line is an adequate model for studying pHi phenomena of hind gut epithelial cells. PMID- 9366080 TI - Transepithelial SCFA fluxes link intracellular and extracellular pH regulation of mouse colonocytes. AB - We have studied pH regulation in both intracellular and extracellular compartments of mouse colonic crypts, using distal colonic mucosa with intact epithelial architecture. In this work, we question how transepithelial SCFA gradients affect intracellular pH (pHi) and examine interactions between extracellular pH (pHo) and pHi regulation in crypts of distal colonic epithelium from mouse. We studied pH regulation in three adjacent compartments of distal colonic epithelium (crypt lumen, crypt epithelial cell cytosol, and lamina propria) with SNARF-1 (a pH sensitive fluorescent dye), digital imaging microscopy (for pHi), and confocal microscopy (for pHo). Combining results from the three compartments allows us to find how pHi and pHo are regulated and related under the influence of physiological transepithelial SCFA gradients, and develop a better understanding of pH regulation mechanisms in colonic crypts. Results suggest a complex interdependency between SCFA fluxes and pHo values, which can directly affect how strongly SCFAs acidify colonocytes. PMID- 9366081 TI - Surface pH of the distal colonic epithelium of guinea-pigs. AB - A method for the continuous measurement of proton activity at the luminal surface of the gastro intestinal mucosa was developed. The pH-sensitive fluorescent dye 5 N-hexadecanoyl-amino fluorescein (HAF) was used to monitor the surface pH (pHs). HAF integrates in the apical membrane of the colonic cells because of its amphophilic character. By excitation at two different wavelengths, the ratio of the two fluorescence intensities corresponds to the pHs. pHs in the presence of bicarbonate is relatively independent of the luminal pH. In bicarbonate-free, HEPES-buffered solutions, such a constant "microclimate" was not present. Addition of 113 mmol.l-1 butyrate to the luminal solution caused an increase of the surface pH by 0.14 +/- 0.07 (n = 18) pH units in bicarbonate-containing medium. This increase was not observed in bicarbonate-free medium, indicating that the increase in pHs is due to a gain of bicarbonate during butyrate absorption. PMID- 9366082 TI - Intracellular pH in rat pancreatic ducts. AB - In order to study the mechanism of H+ and HCO3- transport in a HCO3- secreting epithelium, pancreatic ducts, we have measured the intracellular pH (pHi) in this tissue using the pH sensitive probe BCECF. We found that exposures of ducts to solutions containing acetate/acetic acid or NH4+/NH3 buffers (20 mmol/l) led to pHi changes in accordance with entry of lipid-soluble forms of the buffers, followed by back-regulation of pHi by duct cells. In another type of experiment, changes in extracellular pH of solutions containing HEPES or HCO3-/CO2 buffers led to significant changes in pHi that did not seem to be back-regulated efficiently by duct cells. The sensitivity of pHi to the inhibitor HOE 694 and to changes in Na+ gradients, indicate that the Na+/H+ exchanger is present in this epithelium. Similarly, the sensitivity to Cl- and HCO3- gradients indicated the presence of the Cl-/HCO3- exchanger. Under some conditions, these exchangers can be invoked to regulate cell pH. PMID- 9366083 TI - Defensive production of quinoline by a phasmid insect (Oreophoetes peruana). AB - Adults and nymphs of the Peruvian stick insect Oreophoetes peruana (order Phasmatodea) have a pair of thoracic glands from which they discharge a malodorous fluid when disturbed. The secretion contains a single volatile component, quinoline. Quinoline has not been reported previously from an animal source. The compound proved repellent or topically irritant in assays with ants, spiders, cockroaches and frogs. O. peruana nymphs, at molting, do not extricate the shed cuticular lining of the glands, thereby managing not to lose their secretory supply when they cast their skin. They are able, as a consequence, to discharge secretion even while still teneral after molting. PMID- 9366084 TI - Acid-base regulation in tadpoles of Rana catesbeiana exposed to environmental hypercapnia. AB - Tadpoles of Rana catesbeiana were exposed to different levels of environmental hypercapnia. The acid-base regulatory response differed from that in adult amphibians in showing a high degree of pH compensation in the extracellular fluid (65-85%) and complete compensation in the intracellular fluid (tail muscle and liver) within 24 h. Hypercapnia induced a massive transfer of HCO3- equivalents and Ca2+ from the tadpoles to the environment, which lasted some 4-6 h. Bicarbonate accumulated in the body fluids came mainly from internal buffer sources (probably CaCO3 in lime sacs and/or skin deposits). It is suggested that the large bicarbonate efflux from the animal is a consequence of the dissolution of CaCO3 stores and the delayed adjustment of bicarbonate-retaining mechanisms. Re-exposure of tadpoles to hypercapnia after 1-3 weeks of normocapnic recovery only affected transepithelial fluxes of acid-base equivalents marginally, suggesting that mobilisable CaCO3 stores were depleted during the first exposure to hypercapnia and that they were not refilled. The CaCO3 stores may normally be mobilised during the slowly developing internal hypercapnia that occurs during metamorphosis. PMID- 9366085 TI - The effects of artificial lung inflation on pulmonary blood flow and heart rate in the turtle Trachemys scripta. AB - As for most ectothermic vertebrates, the breathing pattern of turtles is episodic, and pulmonary blood flow (Qpul) and heart rate (fH) normally increase several-fold during spontaneous ventilation. While some previous studies suggest that these cardiovascular changes are caused by stimulation of pulmonary stretch receptors (PSRs) during ventilation, it has been noted in other studies that blood flows often change prior to the initiation of breathing. Given the uncertainty regarding the role of PSRs in the regulation of central vascular blood flows, we examined the effect of manipulating lung volume (and therefore PSR stimulation) on blood flows and heart rate in the freshwater turtle Trachemys scripta. Turtles were instrumented with blood flow probes on the left aortic arch and the left pulmonary artery for measurements of blood flow, and catheters were inserted into both lungs for manipulation of lung volume. In both anaesthetized and fully recovered animals, reductions or increases in lung volume by withdrawal of lung gas or injection of air, N2, O2 or 10% CO2 (in room air) had no effect on blood flows. Furthermore, simulations of normal breathing bouts by withdrawal and injection of lung gas did not alter Qpul or fH. We conclude that stimulation of PSRs is not sufficient to elicit cardiovascular changes and that the large increase in Qpul and fH normally observed during spontaneous ventilation are probably caused by a simultaneous feedforward control of central origin. PMID- 9366086 TI - Control of venom production and secretion by sympathetic outflow in the snake Bothrops jararaca. AB - Many studies have examined the morphological and biochemical changes in the secretory epithelium of snake venom glands after a bite or milking. However, the mechanisms of venom production and secretion are not yet well understood. The present study was undertaken to evaluate the role of the sympathetic nervous system in the control of venom production and secretion. Venom glands were obtained from Bothrops jararaca (Viperidae) snakes, either unmilked previously or milked 4, 7 or 15 days before they were killed. Levels of tyrosine-hydroxylase like immunoreactivity were higher in venom glands collected 4 days after milking, coinciding with the maximal synthetic activity of the secretory cells. The only catecholamine detected by high-performance liquid chromatography was noradrenaline, indicating the presence of noradrenergic fibres in these glands. In reserpine-treated milked snakes, no venom could be collected, and electron microscopic analysis showed narrow rough endoplasmic reticulum cisternae, instead of wide cisternae, and less well-developed Golgi apparatus compared with milked untreated snakes, indicating impairment of protein synthesis and secretion. The administration of isoprenaline or phenylephrine (beta- and alpha-adrenoceptor agonists, respectively) to reserpine-treated milked snakes promoted the widening of the rough endoplasmic reticulum and restored venom production, but only phenylephrine restored the development of the Golgi apparatus and the formation of many secretory vesicles. These results provide the first evidence that the sympathetic nervous system plays an important role in venom production and secretion in the venom glands of Bothrops jararaca. Understanding the importance of noradrenergic stimulation in venom production may provide new insights for research into the treatment of snakebites. PMID- 9366087 TI - Intracellular Ca2+ release mediated by metabotropic glutamate receptor activation in the leech giant glial cell. AB - We have investigated the effects of glutamate and glutamate receptor ligands on the intracellular free Ca2+ concentration ([Ca2+]i) and the membrane potential (Em) of single, identified neuropile glial cells in the central nervous system of the leech Hirudo medicinalis. Exposed glial cells of isolated ganglia were filled iontophoretically with the Ca2+ indicator dye Fura-2. Application of glutamate (200-500 mumoll-1) caused biphasic membrane potential shifts and increases in [Ca2+]i, which were only partly reduced by either removing extracellular Ca2+ or blocking ionotropic glutamate receptors with 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 50-100 mumol l-1. Metabotropic glutamate receptor (mGluR) ligands had the following rank of potency in inducing a rise in [Ca2+]i: quisqualate (QQ, 200 mumol l-1) > glutamate (200 mumol l-1) > L(+)2-amino-3-phosphonopropionic acid (L AP3, 200 mumol l-1 > trans-1-aminocyclopentane-1,3-dicarboxylic acid (t-ACPD, 400 mumol l-1). The mGluR-selective antagonist (RS)-alpha-methyl-4 carboxyphenylglycine [(RS)-MCPG, 1 mmol l-1] significantly reduced glutamate evoked increases in [Ca2+]i by 20%. Incubation of the ganglia with the endoplasmic ATPase inhibitor cyclopiazonic acid (CPA, 10 mumol l-1) caused a significant (53%) reduction of glutamate-induced [Ca2+]i transients, while incubation with lithium ions (2 mmol l-1) resulted in a 46% reduction. The effects of depleting the Ca2+ stores with CPA and of CNQX were additive. We conclude that glutamate-induced [Ca2+]i transients were mediated by activation of both Ca(2+)-permeable ionotropic non-NMDA receptors and of metabotropic glutamate receptors leading to Ca2+ release from intracellular Ca2+ stores. PMID- 9366088 TI - Hypoxia and ischaemia in buffer-perfused toad hearts. AB - Previous studies on the effects of ischaemia or hypoxia in ectothermic vertebrate hearts have generally used preparations that were not performing at physiological levels of pressure and flow. The conclusions that ischaemia or hypoxia are not stressful to these organisms were examined in another species, Bufo marinus, in which a buffer-perfused heart was performing physiological levels of work. The in situ preparation demonstrated the Frank-Starling relationship and mechanical characteristics similar to the hearts of intact animals. The hearts recovered from 60 min of ischaemia and reperfusion with no reduction in pressure, flow or heart rate parameters. Hearts exposed to 30 min of hypoxia at physiological filling and diastolic afterload pressures ceased generating a continuous cardiac output during the hypoxia. In most cases, there was a gradual reduction of cardiac output to zero, but in 27% of the hearts studied, intermittent beating was observed. During reoxygenation, the hearts recovered 50-90% of their prehypoxic function and were damaged. Hearts exposed to hypoxia with reduced filling and diastolic afterload continued to develop a cardiac output throughout the hypoxia and demonstrated an overshoot phenomena with the onset of reoxygenation. If demand is in the normal range at the onset of hypoxia, the hearts intrinsically reduce demand either by reducing pressure development or by conversion to intermittent beating. Toad hearts appear not to be damaged by ischaemia, a condition in which demand is low. PMID- 9366089 TI - Effect of nitrogen source on biosynthesis of rapamycin by Streptomyces hygroscopicus. AB - Six non-amino acid nitrogen compounds were examined as nitrogen source for growth of Streptomyces hygroscopicus and biosynthesis of rapamycin. Of the nitrogen sources studied, ammonium sulfate was the best with respect to formation of rapamycin, and supported cell growth comparable to the organic nitrogen sources used in the control chemically defined medium, i.e., aspartate, arginine plus histidine. In the new chemically defined medium, which is buffered with 200 mM 2 (N-morpholino)ethanesulfonic acid to prevent decline of pH during fermentation, an ammonium sulfate concentration of 40 mM was optimal for biosynthesis of rapamycin. Rapamycin production increased by more than 30% on both volumetric and specific bases as compared to the previous medium containing the three amino acids as nitrogen source. PMID- 9366090 TI - Production of recombinant herpes simplex virus protease in 10-L stirred vessels using a baculovirus-insect cell expression system. AB - A gene expression system using recombinant Autographa california nuclear polyhedrosis virus (baculovirus) and Sf-9 cells has been scaled up to the 10-L tank level and shown to be capable of producing herpes simplex virus (HSV) protease in serum-free media. High densities of Spodoptera frugiperda (Sf-9) cells were achieved by modifying two 10-L Biolafitte fermenters specifically for insect cell growth. The existing Rushton impellers were replaced by marine impellers to reduce shear and the aeration system was modified to allow external addition of air/O2 mixtures at low flow rates through either the sparge line or into the head space of the fermenter. To inoculate the tanks, Sf-9 cells were adapted to grow to high cell densities (6-10 x 10(6) cells ml-1) in shake flasks in serum-free media. With these procedures, cell densities of 5 x 10(6) cells ml 1 were routinely achieved in the 10-L tanks. These cells were readily infected with recombinant baculovirus expressing the 247-amino acid catalytic domain of the HSV-1 strain 17 protease UL26 gene as a glutathione-S-transferase (GST) fusion protein (GST-247). Three days after infection at a multiplicity of infection (MOI) of 3 pfu cell-1, the GST-247 fusion protein was purified from a cytoplasmic lysate by Glutathione Sepharose 4-B affinity chromatography with reproducible yields of 11-38 mg L-1 of recombinant protein and > or = 90% purity. Maximum production of this protein was observed at a cell density of 5.0 x 10(6) cells ml-1. PMID- 9366091 TI - Production of xanthan gum by Sphingomonas bacteria carrying genes from Xanthomonas campestris. AB - Twelve genes coding for assembly, acetylation, pyruvylation, polymerization, and secretion of the polysaccharide xanthan gum are clustered together on the chromosome of the bacterium Xanthomonas campestris. These genes (gumBCDEFGHIJKLM) are sufficient for synthesis of xanthan gum when placed in bacteria from a different genus, Sphingomonas. The polysaccharide from the recombinant microorganism is largely indistinguishable, structurally and functionally, from native xanthan gum. These results demonstrate that a complex pathway for biosynthesis of a specific polysaccharide can be acquired by a single inter generic transfer of genes between bacteria. This suggests the biological and commercial feasibility of synthesizing xanthan gum or other polysaccharides in non-native hosts. PMID- 9366092 TI - Microscopic study of migration of microbes in food-packaging paper and board. AB - The microbiological barrier properties of food-packaging paperboards, coated with polyethylene, mineral pigment or a biodegradable polymer and of high-density paper were examined with confocal laser scanning microscopy. The results show that the spatial distribution of microscopically observable bacterial cells was uneven inside the paperboard. The concentration in the interface between the polyethylene coating and the cellulose fibers was 100-200 times higher than inside the cellulose matrix. The bacteria in the interface and the mineral coating layer grew in response to access to food and moisture, whereas no growth was observed inside the fiber web, not even after extended exposure for up to 90 days. The paper and paperboards studied contained soluble nutrients (C:N:P 54:9:1 to 309:3:1) and no measurable antimicrobial activity. The factor limiting growth and migration of bacteria inside the fiber web was most likely limited access to free water, even under conditions of extensive wetting. The studied paperboards functioned as efficient barriers against translocation of microbes. The microbes residing between the paperboard and its polymer coating facing food, was the only potential site from which microbes could leak into food. This emphasizes the need for high hygienic quality of surface-sizing chemicals. Mineral-coating pigments were a source of microbes and their application behind the PE coating facing food is contraindicated. PMID- 9366093 TI - Ethanol increases carotenoid production in Phaffia rhodozyma. AB - Addition of ethanol (0.2%) to cultures of the yeast Phaffia rhodozyma increased the specific rate of carotenoid production [(carotenoid)(cell mass)-1(time)-1]. The incremental increase in carotenoid synthesis with ethanol was highest in carotenoid-hyperproducing strains. Ethanol increased carotenoid production when it was added at various points during the lag and active growth phases. Ethanol increased alcohol dehydrogenase and hydroxy-methylglutaryl-CoA (HMG-CoA) reductase activities. Our results indicate that increased carotenoid production by ethanol is associated with induction of HMG-CoA reductase and possibly activation of oxidative metabolism. PMID- 9366094 TI - Expression of the Bacillus licheniformis PWD-1 keratinase gene in B. subtilis. AB - The kerA gene which encodes the enzyme keratinase was isolated from the feather degrading bacterium Bacillus licheniformis PWD-1. The entire gene, including pre , pro- and mature protein regions, was cloned with Pker, its own promoter, P43, the vegetative growth promoter, or the combination of P43-Pker into plasmid pUB18. Transformation of the protease-deficient strain B. subtilis DB104 with these plasmids generated transformant strains FDB-3, FDB-108 and FDB-29 respectively. All transformants expressed active keratinase in both feather and LB media, in contrast to PWD-1, in which kerA was repressed when grown in LB medium. With P43-Pker upstream of kerA, FDB-29 displayed the highest activity in feather medium. Production of keratinase in PWD-1 and transformants was further characterized when glucose or casamino acids were supplemented into the feather medium. These studies help understand the regulation of kerA expression and, in the long run, can help strain development and medium conditioning for the production of this industrially important keratinase. PMID- 9366095 TI - Comparison of fluorinated polymers against stainless steel, glass and polypropylene in microbial biofilm adherence and removal. AB - Biofilm formation is a long-standing problem in ultrapure water and bioprocess fluid transport lines. The standard materials used in these applications (316L stainless steel, polypropylene and glass) have long been known to be good surfaces for the attachment of bacteria and other biological materials. To compare the relative tenacity of biofilms grown on materials used in manufacturing processes, a model system for biofilm attachment was constructed that approximates the conditions in industrial process systems. New fluorinated polymers were compared to the above materials by evaluating the surface area coverage of bacterial populations on materials before and after mild chemical treatment. In addition, contact angle studies compared the relative hydrophobicity of surfaces to suspensions of bacteria in growth media, and scanning electron microscopy and atomic force microscopy studies were used to characterize surface smoothness and surface defects. Biofilm adherence to polymer based substrata was determined to be a function of both surface finish and surface chemistry. Specifically, materials that are less chemically reactive, as indicated by higher contact angle, can have rougher surface finishes and still be amenable to biofilm removal. PMID- 9366096 TI - Xanthohumols, diacylglycerol acyltransferase inhibitors, from Humulus lupulus. AB - A methanol extract of hops of Humulus lupulus (L.) showed inhibitory activity against rat liver diacylglycerol acyltransferase (DGAT). From DGAT inhibitory activity-guided fractionation, two chalcones were isolated. One was identified as xanthohumol and the other was found to be a new product designated xanthohumol B. The structure of xanthohumol B was shown to be 6-[3,4-dihydro-3,5-dihydroxy-7 methoxy-2,2-dimethyl-2H-benzo[b]pyrano ]- 3-(4-hydroxyphynyl)-2-propen-l-one by spectroscopic studies including various NMR measurements. Xanthohumol and xanthohumol B inhibited DGAT activity with IC50 values of 50.3 and 194 microM in rat liver microsomes, respectively. They showed preferential inhibition of triacylglycerol formation in intact Raji cells, indicating that they inhibit DGAT activity preferentially in living cells. PMID- 9366098 TI - Two new pregnane-type steroidal alkaloids from Sarcococca saligna. AB - Two new preganae-type steroidal alkaloids, (20S, 2'Z)-20- (N,N-dimethylamino)-3 beta-(2-methyl-2Z-butenamido)-pregn-5-en-4-one and (20S, 2'Z)-20-(N,N dimethylamino)-3 beta-(2-methyl-2Z-butenamido)- pregna-5,14-dien-4-one, have been isolated from an ethanolic extract of the roots and stems of Sarcococca saligna, in addition to the two known alkaloids, N-formylchonemorphine and vaganine-A, which have been isolated for the first time from this species. PMID- 9366097 TI - Carbazole alkaloids from Murraya koenigii. AB - Two new alkaloids, 9-carbethoxy-3-methylcarbazole and 9-formyl-3-methylcarbazole, and a known metabolite, 3-methyl-carbazole were isolated from the roots of Murraya koenigii. All three compounds were identified by detailed spectral analyses including 2D NMR studies and their structures confirmed by synthesis. Of the two new metabolites, the 9-formyl compound displayed weak cytotoxicity against both mouse melanoma B16 and adriamycin-resistant P388 mouse leukemia cell lines. PMID- 9366099 TI - [Effects of hormone replacement treatment of menopause on the risk of venous thromboembolic disease]. AB - Post-menopausal hormone replacement therapy increases the risk of venous thrombo embolism 2- to 4-fold. The risk is highest in the beginning of the exposure to hormones and disappears rapidly after interruption of treatment. However, the increased risk remains low in absolute value and has to be weighed against coronary artery disease and post-menopausal osteoporosis. PMID- 9366100 TI - The Eurevie Study: contrasting effect of piretanide and thiazides in mild to moderate hypertension. AB - This study compares the loop diuretic piretanide 6 mg in a slow-release formulation (PIR) with hydrochlorothiazide 25 mg (HCT) and the fixed combination altizide 15 mg-spironolactone 25 mg (ALT-SP) in hypertension. 1105 mild to moderate hypertensive patients entered a three-week placebo wash-out period; 899 were randomized in a 6-month, double-blind, parallel group treatment phase; 800 completed the study. Primary end-points; serum potassium concentration and quality of life at one month; secondary end-points: ionic, renal and metabolic variables; blood pressure (BP) measurements. HCT and ALT-SP were compared only to PIR using Dunnett's or chi 2 tests. RESULTS: No difference was found for the overall quality of life. No change of serum potassium concentration at one month was found in PIR while small decreases were detected with ALT-SP (-0.1 mM) and HCT (-0.26 mM). Serum creatinine concentration increased significantly in ALT-SP when compared to PIR. All the drugs were effective in reducing BP: HCT had a higher rate of responders than PIR with similar mean BP falls and ALT-SP induced greater falls in blood pressure. CONCLUSION: PIR proves to be a potent antihypertensive drug without significant effect on serum electrolytes, plasma glucose and lipids. HCT was slightly more potent but induced a fall in serum potassium concentration with a significant risk of hypokalaemia. The addition of SP to ALT led to a more potent diuretic with a higher level of serum potassium and plasma creatinine disturbances. PMID- 9366101 TI - [Double-blind randomized comparative study of nicergoline naftidrofuryl on the quality of life in chronic obliterative arteriopathy of lower limbs with intermittent claudication]. AB - The functional limitation of patients with obliterative arterial disease, and with intermittent claudication, damages their quality of life. The purpose of this trial was to compare the effects of nicergoline and naftidrofuryl on the quality of life and the functional discomfort of the 131 patients with claudication. It was a multicentre, randomised, double-blind trial with parallel groups. The patients were asked to complete a quality of life questionnaire and a Visual Analogue Scale, and to evaluate the number of steps on flat ground before the pain began. After 6 months of treatment, we observed, for all treatments combined, a significant improvement (p = 0.0001) in the quality of life and in the functional discomfort. Three variables favoured nicergoline: the estimated time before the onset of the pain (p = 0.003), the functional discomfort quantified by the Visual Analogue Scale (p < 0.05), the distance covered on flat ground (p = 0.013). The other variables, and especially the total score on the self-questionnaire, confirmed this impression, without reaching significance (p = 0.136). The data suggest that in terms of quality of life nicergoline is superior. The clinical tolerance is good and comparable between the two treatments. PMID- 9366102 TI - [Demonstration of differences in the effect of 2 antihypertensive agents by self blood pressure measurement: comparison of trandolapril and perindopril]. AB - In this double blind randomized study, blood pressure lowering effects and duration of action of two angiotensin converting enzyme (ACE) inhibitors were compared using home self blood pressure measurement (SBPM). After a two-week placebo run-in period, 128 hypertensive patients received during four weeks a daily morning dose of either perindopril (P) 4 mg or trandoplapril (T) 2 mg. One week of SBPM was planned at the end of both the run-in and the treatment period. Three consecutive measurements, with printed results, were requested in the morning before drug intake and in the evening. Run-in period home systolic (SBP) and diastolic (DBP) blood pressures were comparable in both groups: 149.9 +/- 14.5/97.3 +/- 8.1 mmHg in the P group (n = 63), 148.9 +/- 14.3/96.7 +/- 6.9 mmHg in the T group (n = 65). During the treatment period, evening BP was similar in the 2 groups: 139.1 +/- 14.3/89.9 +/- 9.1 mmHg in P group, 137.5 +/- 15.3/89.4 +/ 9.1 mmHg in T group (NS). On the other hand, morning BP was higher in the P group: 143.1 +/- 16.3/93.8 +/- 9.6 mmHg vs 137.4 +/- 16.7/90.3 +/- 9.7 mmHg (p < 0.05 for SBP and DBP-Student's t test). These results were confirmed by co variance analysis after adjustment on initial BP. Due to standardized conditions of measurement, home SBPM was able to show a difference in BP lowering effects at the end of the inter-dose interval between two ACE inhibitors. PMID- 9366103 TI - [Comparison of antihypertensive and metabolic effects of lisinopril 20 mg/hydrochlorothiazide 12.5 mg fixed combination and captopril 50 mg/hydrochlorothiazide 25 mg fixed combination]. AB - The antihypertensive and metabolic effects of lisinopril 20 mg/hydrochlorothiazide 12.5 mg in fixed combination were compared with those of captopril 50 mg/hydrochlorothiazide 25 mg in fixed combination in a double-blind clinical trial. After a 3-week placebo run-in period, two parallel groups of hypertensive patients (188 patients in total) each received one treatment once a day for 6 weeks. Blood pressure was measured with a mercury sphygmomanometer and on two occasions by 24 h ambulatory blood pressure monitoring (ABPM). Results indicate that both treatments have similar effects on casual blood pressure measurements, while ABPM recordings show that the lisinopril 20 mg/hydrochlorothiazide 12.5 mg combination is more effective during the last period of the dosing interval. Lisinopril 20 mg/hydrochlorothiazide 12.5 mg as combination antihypertensive treatment does not induce alterations in serum potassium and triglycerides. PMID- 9366104 TI - [Comparative study of French drug data banks]. AB - We proposed a set of 9 criteria to evaluate computerized French drug data banks currently available on the Minitel, medical software, or the Web. These criteria are used for testing the scientific quality of the information provided in terms of reliability and completeness. They round off the nine criteria proposed in a previous study for sole drug interactions. None of the drug data banks is better than the others on all the selected dimensions. But the methodology presented should allow a particular user with defined needs to weigh up the criteria and optimize his choice. PMID- 9366105 TI - [Cannabis: toxicokinetic focus and methodology of urinary screening]. AB - Cannabis is the most commonly used illicit drug in the world. The major psychomimetic compound is delta 9-tetrahydrocannabinol. The major effects consist in alterations of sensory perception, cognition, motor coordination and self perception. Procedures designed to detect cannabis use have been developed since 1988. The traditional approach is to screen urine by immunoassay and to submit positive samples for confirmation by gas chromatography and mass spectrometry. There continue to be many difficulties in interpreting the results because of the biotransformations of delta 9-tetrahydrocannabinol. PMID- 9366106 TI - [Non-parametric estimation of pharmacokinetic parameters of amikacin in patients with non-insulin-dependent diabetes mellitus]. AB - To establish a reference for MAP Bayesian adaptive control of amikacin therapy in non-insulin-dependent diabetic patients, 30 patients (age: 63.5 +/- 10.1 years) were studied. Weight (84.2 +/- 15.4 kg) and body mass index (28.0 +/- 4.3 kg/m2 for males and 30.5 +/- 6.4 kg/m2 for females) were stable during treatment. Creatinine clearance (CCr) was 70.3 +/- 27.2 ml/min/1.73 m2 before treatment and 69.6 +/- 24.3 ml/min/1.73 m2 (NS) at the end of treatment (2 to 15 days). 129 serum concentrations were drawn (4.8 +/- 2.6 levels per patient). The one compartment model was parameterized as having Vs (l.kg-1) and Kslope (min/ml.h) for each unit of CCr (Kel = Kintercept + Kslope x CCr). The non-renal Kintercept was fixed at 0.00693 h-1. The NPEM computes the joint probability densities. The mean, median, and SD were respectively: Vs = 0.3574, 0.3654, 0.0825 l.kg-1; Kslope = 0.0026, 0.0027, 0.0007 min/ml.h. For the a priori first doses determination, precision is higher with the new population. No difference in adaptive control was observed. In additive, the full joint density probability should be used to develop stochastic multiple model linear quadratic (MMLQ) adaptive control strategies. PMID- 9366107 TI - Neuroleptic-resistant schizophrenic patients treated by clozapine: clinical evolution, plasma and red blood cell clozapine and desmethylclozapine levels. AB - The aim of this open study was to determine a more rational therapeutic approach for psychotic patients treated with clozapine for several months, using measurement of plasma and red blood cell levels (P, RBC) of clozapine (cloza) and N-desmethylclozapine (descloza), the major metabolite of clozapine, which has been reported to be less active but more toxic (agranulocytosis) than clozapine itself. The RBC concentration may be considered as more representative of the free fraction drug. The study concerned 7 patients suffering from chronic paranoid schizophrenia according to the DSM-IV criteria. All of them were treatment-refractory schizophrenic inpatients (4 men, 3 women, mean age +/- SD: 38.2 +/- 8.4 years; mean duration of illness +/- SD: 14.4 +/- 5.1 years). They had received at least two different neuroleptics, for 6 weeks, before entering the study. Treatment started in our hospitalization unit with clozapine 25 mg up to a maximum of 900 mg/d (mean stabilized daily dose +/- SD: 507 +/- 211 mg and mean daily dose per kg: 6.91 +/- 3.08 mg). Clinical evaluations (Quality of Life Scale: QLS), regular blood monitoring and biological samples were conducted at the same time, weekly for 18 weeks and then monthly (duration of the study: 4 to 38 months; mean +/- SD: 12.9 +/- 11.5 months). Plasma and RBC (after lysis) levels were determined by reversed phase HPLC and UV detection after extraction with hexane. All the patients improved very quickly after the first week of treatment and six were able to leave the hospitalization unit and start outpatient care such as daily hospitalization, returning home or in sheltered accommodation. With the following plasma (P) and RBC levels: mean cloza +/- SD: (P = 294 +/- 146 ng/ml; RBC = 110 +/- 82 ng/ml) and mean descloza +/- SD: (P = 173 +/- 106 ng/ml; RBC = 76 +/- 54 ng/ml); none of the seven patients developed agranulocytosis. The blood levels, ensuring better surveillance, have a predictive value for clinical improvement. A linear pharmacoclinical correlation was only found between RBC cloza concentrations and the evolution of the QLS scores. Clozapine fulfils the criteria for therapeutic drug monitoring, and determination of plasma, and more particularly RBC, cloza and descloza levels may help to find the lowest effective dose with the fewest side effects. PMID- 9366108 TI - [15th consensus conference on intensive care and emergency medicine. Use of catecholamines in septic shock (adults-children)]. PMID- 9366109 TI - [Contribution of molecular biology to the diagnosis of monogenic hereditary nephropathies]. AB - Schematically, gene identification can be achieved by functional cloning, based on preexisting knowledge about the basic biochemical defect, positional cloning, initiated by the mapping of the responsible gene to its correct location on a chromosome, or by a combination of these two approaches called "candidate gene" approach. Genes of numerous monogenic hereditary renal disorders have been identified during the last few years by one of these approaches, particularly, the PKD1 and PKD2 genes involved in autosomal dominant polycystic kidney disease, as well as the genes encoding different type IV collagen alpha chains, responsible for Alport syndrome. This allows novel insights in the understanding of the pathogenesis of hereditary renal diseases and has opened new areas of genetic diagnosis. PMID- 9366110 TI - [Cystic kidney diseases]. AB - Among all inherited cystic kidney diseases, the commonest are polycystic kidney diseases, which include 2 diseases characterized by their pathological characteristics and their mode of inheritance, namely autosomal dominant or recessive. Autosomal dominant polycystic kidney disease is usually diagnosed in adulthood and is related at least to 2 different genes; PKD1 gene on chromosome 16 accounts for 85% of cases. This frequent disease (1 in 1,000 people) leads to end-stage renal failure in most patients at a mean age of 55 years. Renal ultrasonography allows its detection at an early stage, during childhood or adolescence, and even in utero in some cases. Autosomal recessive polycystic kidney disease, related to a single gene mapped to chromosome 6, is a rare disease, usually diagnosed during infancy because of enlarged kidneys and hypertension. The early occurrence of advanced renal failure is uncommon and only 1/3 of patients require renal replacement therapy during childhood. The term "polycystic kidney disease" should be limited to these 2 diseases; however there are many other inherited conditions including renal cysts like tuberous sclerosis or Hippel-Lindau's disease in adults, and several malformative syndromes in children. PMID- 9366111 TI - [Nephronophthisis]. AB - Nephronophthisis is an autosomal recessive tubulointerstitial nephropathy leading to end-stage renal failure during adolescence or early adulthood. Initial symptoms of pitressoresistant polyuria and polydipsia start around 3 years of age, increase over the following years and are often responsible for growth retardation. Renal function declines slowly and end-stage renal failure occurs around 12 years of age in most cases. At ultrasound examination, kidneys have a normal or slightly decreased size, parenchymal echogenicity is increased and the differentiation is reduced. When they are present, medullary cysts are an important feature. Renal biopsy shows atropic or dilated tubules, with irregular thickened basal membranes. Interstitial fibrosis and glomerular sclerosis develop progressively. Various extrarenal abnormalities have been reported in association with nephronophthisis; the most frequent is congenital amaurosis. The most recent advance is the localization of a gene (NPH1) on chromosome 2q13. Deletions in this gene have been shown in about 80% of patients with isolated renal involvement. Such deletions have never been reported when nephronophthisis is associated with congenital amaurosis. The evidence of a deletion in NPH1 gene now allows the diagnosis of nephronophthisis to be performed without renal biopsy. When a delation has been demonstrated in one child, the identification of the deletion in siblings allows to determine those who are affected and those who are not, to propose a reliable prenatal diagnosis. PMID- 9366112 TI - [Familial hematuric nephropathies]. AB - Alport syndrome is a hereditary hematuric nephritis progressing to end-stage renal failure, often associated with hearing loss and specific ocular changes. It is characterized by the presence of thickening and splitting of the glomerular basement membrane. Defects in type IV collagen, the main component of basement membranes, are responsible for the disease. The prevalence rate of Alport syndrome is 1/5,000 and it is the cause of about 2% of end-stage renal failure. The disease is heterogenous both at the clinical and genetic level. In most kindreds, it is transmitted as an X-linked dominant trait: males are severely affected whereas most females have a benign disease. The genes coding the different chains of type IV collagen have been cloned and several mutations have been characterized. Since prenatal counselling is now possible, the recognition of this severe familial under-diagnosed disease is of the upmost importance. PMID- 9366113 TI - [Infantile cystinosis]. AB - Infantile cystinosis is a metabolic lysosomal storage disease of cystine affecting most of the body cells. The first symptoms appear after 5-6 months of life: anorexia, vomiting, polyuria, polydipsia and failure to thrive, associated with the signs of tubular Fanconi syndrome including glycosuria, proteinuria, loss of bicarbonate, phosphate, potassium, sodium, etc. Treatment with cysteamine is effective if started as early as possible. This treatment delays or prevents the spontaneous evolution toward end-stage renal failure, usually between 6 and 12 years of age, and also prevents growth stunting. In the long term, other organs may be involved like eye, thyroid, endocrine pancreas, muscle and central nervous system. The diagnosis is ascertained by leucocytes cystine assay, also useful for the follow up and the adjustment of the treatment. Prenatal diagnosis is available on chorionic sample. The gene of the disease is not yet identified but is known to map to chromosome 17. PMID- 9366114 TI - [Hereditary diseases causing kidney calculi]. AB - Urolithiasis and/or nephrocalcinosis due to hereditary diseases are a rare event which must be kept in mind of physicians who take care of children (10 to 40% of all causes of lithiases) as well as of adults (less than 15% of all causes of lithiases) since a specific management is usually required. The most frequent inborn disorders are idiopathic hypercalciuria, distal tubular acidosis, cystinuria and hyperoxaluria. Stone formation is always secondary to an increased urine concentration of promotors, i.e. calcium, oxalate, phosphate, cystine, xanthine. One of the most informative diagnosis investigation is infrared spectrophotometry which can identify stone composition. When such a technique is not available, biochemical investigations should be adapted to both personal and family history. In addition to high fluid intake (2 to 3 L/m2/24 h) sometimes associated with alcalinisation, the management of hereditary stone disease requires specific procedure. In all cases, the long-term renal prognosis is related to both primary disease and therapeutic compliance. PMID- 9366115 TI - [Non-lithiasic hereditary tubulopathies]. AB - Renal tubular disorders include various clinical conditions wherein the renal tubular reabsorption of an ion or organic solute is significantly decreased. It may concern the renal handling of a single substance, such as glucose or phosphate, a group of substances or a combination of ions and organic substances. Close to this group of diseases, it is also possible to consider two conditions due to renal tubular resistance to vasopressin and parathyroid hormone: congenital nephrogenic diabetes insipidus and pseudohypoparathyroidisms, respectively. Clinically, the urinary loss of these substances may be inapparent, like in familial glucosuria, but in most cases, it may be responsible for characteristic disorders such as failure to thrive, dehydration, rickets, etc. Recently, physiological and molecular cloning studies have brought crucial information for testing candidate genes and understanding the underlying molecular bases of these disorders. PMID- 9366116 TI - [Hereditary kidney diseases in adults]. AB - Inherited kidney diseases are frequently encountered in adults; the diagnosis is often made and they usually progress to renal failure at this age. Autosomal dominant polycystic kidney disease is the most prevalent. It is one of the most common inherited diseases, involving 1 in 400 to 1,000 individuals. Renal cysts growth is responsible for hypertension and renal failure; polycystic kidney disease represents 6 to 7% of the causes of end-stage renal failure in adults. The disease also encompasses extra-renal localisations, i.e. liver cysts and intra-cranial aneurysms. Multiple renal cysts may be found in other inherited disorders, such as tuberons sclerosis and von Hippel-Lindau disease. Alport syndrome is the second most prevalent inherited kidney disease, characterized by various abnormalities of type IV collagen molecules. Molecular diagnosis is possible in some families, which makes genetic counselling more reliable. Finally renal involvement is frequent in a great variety of inherited metabolic (Fabry's disease, glycogen storage disease type 1, hyperuricemic nephropathy) or non metabolic (nail-patella or Bardet-Biedl syndrome) diseases. PMID- 9366118 TI - [Insulin-dependent diabetes. Etiology, physiopathology, diagnosis, complications, prognosis, treatment]. PMID- 9366117 TI - [Cancer of the colon. Epidemiology, pathological anatomy, Dukes' stage, physiopathology, diagnosis, course, principles of treatment and prevention]. PMID- 9366119 TI - [Psychiatric disorders in pregnancy and post-partum. Diagnosis]. PMID- 9366120 TI - [Convulsions in infants. Diagnostic orientation and management in emergency situation with drug posology]. PMID- 9366121 TI - [Addiction to narcotics. Epidemiology, modality of management, complications; diagnosis and treatment of overdose; clinical manifestations of withdrawal syndrome]. PMID- 9366122 TI - [Disorders of acid-base equilibrium. Physiopathology, diagnosis, treatment]. PMID- 9366123 TI - [Cardiomyopathies. Signs, course, treatment]. PMID- 9366124 TI - Acute monarthritis. PMID- 9366126 TI - Chondroprotection in osteoarthritis. PMID- 9366125 TI - Use of sulfasalazine in rheumatic diseases. PMID- 9366128 TI - The efficacy of a university drug education course on factors that influence alcohol use. AB - The purpose of this investigation was to assess the impact that a Drug Education course has on motives, consequences, attitudes, and perceptions regarding alcohol use in a sample of university students, and to discern if these parameters alter substance usage. There were a total of 121 respondents (32 male, 94 female). Following the course, students reported a slight elevation in the motivation to drink alcohol to facilitate studying. However, drinking because they enjoyed the taste, drinking to get drunk, and drinking to celebrate special occasions decreased significantly following the course. No significant differences were noted in patterns of drinking consequences or selected attitudes toward alcohol use. Students did, however, perceive alcohol to be a more dangerous substance in the post-test. No gender differences were observed. PMID- 9366127 TI - Interventions by students in friends' alcohol, tobacco, and drug use. AB - This article investigates self-reported interventions by students in the alcohol, tobacco, illicit drug use, and drinking-driving of their friends. The data came from a study of 1184 students in Ontario schools in grades 7, 9, 11, and 13. We found that about a third of students intervened in friends' illegal drug use and drinking-driving but about half intervened about smoking. Students who intervened were more likely to be older and spend fewer nights at home. They were less likely to use cannabis, but had more friends using cannabis and illegal drugs. Also, they had more exposure to drug education and were more disapproving of drug use. Drug education may give students the knowledge and confidence to intervene in friends' drug use. PMID- 9366129 TI - Attitudes and knowledge about drinking: relationships with drinking behavior among pregnant teenagers. AB - Data were collected on the drinking behavior of 415 pregnant adolescents from 1990 to 1994. The relationships between knowledge and attitudes about drinking and drinking behavior were examined. Knowledge about drinking was not related to average daily volume of alcohol before or during pregnancy. Those with specific knowledge about fetal alcohol effects drank less before pregnancy, and in the first trimester, and were also less likely to drink to intoxication. Among drinkers, general knowledge about drinking was significantly related to a decrease in drinking between pre-pregnancy and first trimester, as well as between first and third trimesters. Those with more intolerant attitudes about drinking drank less before and during pregnancy. They had fewer episodes of binge drinking, intoxication, negative consequences, and problem drinking during pregnancy. They were more likely to decrease drinking from the first to third trimesters. These relationships are relevant to developing effective education programs for the high-risk group of pregnant teenagers who drink. PMID- 9366130 TI - School personnel training for the prevention of tobacco, alcohol, and other drug use: issues and outcomes. AB - The training of inservice school personnel in the prevention of tobacco, alcohol, and other drug use among youth is the focus of this article. The training emphasizes an interdisciplinary, youth development, school team training model, entitled "Enhancing Student Well-Being." The model includes both content and process components. The manuscript describes the model, evaluation procedures, and training issues. Particular attention is given to follow-up assessment and outcome of school-based prevention projects developed during the training and implemented during the school year. Results support the training model as having a positive impact on prevention initiatives in schools. PMID- 9366131 TI - Educators' perceptions of the D.A.R.E. program. AB - This study examines the perceptions of educators about the Drug Abuse Resistance Education (D.A.R.E.) program, based on the results of a statewide survey among 286 fifth and sixth grade teachers and principals. Educators gave their highest ratings to teacher/officer interaction, the role playing exercises, and the graduation ceremony. Ratings of overall program quality and the impact of the program on students were both high. Block regression analysis was used to examine factors predictive of educators' views of D.A.R.E. D.A.R.E. program elements were the most important factors explaining variance in educators' ratings of over-all program quality and program impact on students. Altogether, 54 percent and 38 percent of the variance in both dependent variables were explained. The results are discussed in terms of the important role teachers and principals play as stakeholders in prevention education. PMID- 9366132 TI - The influence of self-esteem on smoking among African-American school children. AB - This study provides some evidence, although not very strong, that self-esteem is associated with the likelihood of smoking among African-American children. In a sample of 1,256 children, those with lowest levels of self-esteem were twice as likely to have ever smoked as those with highest level of self-esteem (95% C.I. = 1.10-7.78). Girls, more so than boys, have an increased risk of smoking at the lowest level of self-esteem. Girls with the lowest level of self-esteem were 2.8 times (95% C.I. = 3.85-16.59) as likely to have smoked when compared to girls with higher self-esteem. The findings suggest preventive interventions that seek to build self-esteem may reduce the likelihood of smoking among girls, although perhaps only modestly. Further study is needed to identify potentially effective methods for reducing the likelihood of smoking among African-American boys. PMID- 9366133 TI - The role of the church in adolescent drug education. AB - Despite drug education and prevention efforts, adolescent substance use is on the rise in the United States. In an exploration of correlates of substance use and components of effective drug education, three dimensions of religiosity- religious proscriptiveness, involvement in church activities, and the importance an individual places on church activities--emerge. Each has previously demonstrated an inverse relationship with adolescent substance use. In the present study, interactions among these three dimensions were evaluated in 238 adolescents. Religious proscriptiveness interacted with church involvement and with church importance in relation to adolescent use of alcohol, cigarettes, marijuana, and other drugs. Additionally, among adolescents who had ever used alcohol, a positive relationship was observed between religious proscriptiveness and binge drinking such that the highest incidence of binge drinking was reported by those affiliated with proscriptive religious groups. The church may be an important vehicle for drug education. Implications for drug education are discussed, and further research is suggested. PMID- 9366134 TI - Conducting psychoeducational interventions with drug abusing clients: the lifestyle model. AB - A psychoeducational model of intervention is proposed for use with drug abusing clients. This model may be particularly helpful during the early stages of intervention in reducing resistance to change because it addresses the eight thinking styles (mollification, cutoff, entitlement, power orientation, sentimentality, superoptimism, cognitive indolence, discontinuity) believed to shield the drug "lifestyle" from forces that would otherwise bring about change. Practical suggestions are offered as to how this information might be shared with clients. PMID- 9366135 TI - Identification of human skin from tissue fragments left in various conditions using an enzyme immunoassay for squamous cell carcinoma-related antigen. AB - We investigated the possibility of identification of human skin left under various conditions using our original enzyme immunoassay (EIA) for squamous cell carcinoma-related (SCC) antigen. The antigen could be detected in specimens under the following conditions : purified or dried at room temperature for at least 12 months, immersed in fresh water at room temperature for 3 weeks and heated at 100 degrees C for 72 h. PMID- 9366136 TI - Suicide by self-stabbing in the city of Tokyo--a review of accumulated data from 1976 to 1995. AB - Accumulated data of suicide by self-stabbing in the city of Tokyo (population: approx. 8.1 million. 1994) between 1976 and 1995 was reviewed. The overall numbers of suicides for each year were similar (min.: 1178, max.: 1620, 1346.9 on average), while the annual number of unusual death cases increased gradually (5399 in 1976 to 9226 in 1995). The annual number of suicides by self-stabbing fluctuated irregularly, but was generally low (2.3-4.7%) among modes of suicide. A significant difference was observed between the sex ratio in suicidal self stabbing and that for all suicide; the male/female ratio is higher in suicidal self-stabbing than in suicides overall. The majority of fatally wounded body sites were in the neck, chest, abdomen, wrists and forearms. Marked differences according to sex were observed in terms of the implements employed for self stabbing; craft knives, swords and recreational knives, fragments of glass, carpenter's tools and surgical knives were used almost exclusively by men, while more than 80% of women used kitchen knives or razors. No influence of psychiatric history on suicide by self-stabbing was proved. PMID- 9366137 TI - [Neuropathological diagnosis of senile dementia of Alzheimer's type in forensic autopsy cases]. AB - Senile dementia of Alzheimer's type is frequently an underlying cause of accidental death of elderly persons. Neuropathological diagnosis of dementia is therefore crucial to assess the contribution of dementia to the cause of accident. The authors applied two conventional neuropathological criteria described by Khachaturian and Mirra, et al. to three forensic autopsy cases of dementia-related accidental death. In all cases, the number of neocortical senile plaque, a hallmark of dementia, could not fulfill both criteria. This result indicates that foregoing neuropathological criteria derived from fully developed dementia are hardly applicable to elderly persons who died in an early stage of dementia in forensic settings. Further investigation will be required to establish a diagnostic criterion of early stage of dementia. PMID- 9366138 TI - Rapid quantitative analysis of oleandrin in human blood by high-performance liquid chromatography. AB - A simple and rapid method for quantitation of oleandrin in human blood has been developed using an Extrelut column and high-performance liquid chromatography (HPLC). Blood samples spiked with oleandrin were mixed with distilled water and applied to an Extrelut column for elution with ethyl acetate before HPLC. The HPLC separation of the compound from endogeneous impurities was generally satisfactory with the use of a reversed-phase column. Oleandrin showed excellent linearity in the range of 0.05-10 micrograms/g and the limit of detection was 0.02 microgram/g for human blood. The recovery of the compound, which had been spiked to human blood, was more than 90%. The present method is simple and more rapid than those so far reported, and seems useful for analysis of oleandrin in the cases of oleander poisoning. PMID- 9366139 TI - An autopsy case of acute chloroform intoxication after intermittent inhalation for years. AB - A 39-year-old female died shortly after inhalation of chloroform by a saturated towel placed over her face by her lover, who also inhaled and became unconscious. They had inhaled chloroform once or twice a month for about seven years. Fatal level of chloroform was detected in the blood and tissues by gas chromatographic/mass spectrometric analysis. The fragmentation and waviness of cardiomyocytes that indicates hypercontraction, along with the edema and hemorrhage of the lung, shows the presence of acute heart failure possibly caused by arrhythmias or cardiac depression. The unusual numbers of lipofuscin pigments in the heart as well as in the liver may be generated by the chronic use of chloroform. PMID- 9366140 TI - [Two cases of personal identification from dental information]. AB - We describe two cases in which unknown bodies were positively identified from dental information and biochemical examination using tooth materials. In one case, a charred body was positively identified with little effort by comparison of antemortem dental records (dental chart and dental X-ray film) with postmortem data. In the other case, although the unknown individual had dental treatment, the police were unable to obtain the antemortem dental records of the victim. We then conducted biochemical analysis of teeth, facilitating personal identification using DNA analysis and age estimation based on aspartic acid racemization. The mutation obtained from the sequence of mtDNA and the genotypes of HLADQ alpha, HPRTB and ABO blood groups including the data for estimated age supported the kinship between the unknown individual and his mother. The data for maternally inherited mtDNA were of great importance in this case, since it was possible to obtain DNA from the mother. Dental identification in one of the most accurate methods of personal identification if suitable antemortem records are available. In the absence of such records, biochemical analysis of teeth also makes it possible to increase the probability of correct personal identification. PMID- 9366141 TI - [Expression of nitric oxide synthase and its effects on heart failure]. PMID- 9366142 TI - [Pain suppressive effect of low power laser irradiation. A quantitative analysis of substance P in the rat spinal dorsal root ganglion]. AB - The influence of low power laser irradiation on pain was studied by the quantification of substance P in the rat spinal dorsal root ganglion (DRG). Forty one Sprague-Dawley rats were divided into three groups: control (n = 12), stimulated group (n = 16), and laser application group (laser group) (n = 13). Under pentobarbital anesthesia, the right sciatic nerve of rats was exposed. The sciatic nerve was stimulated electrically in the stimulated group and the laser group. The laser irradiation was continued during the electrical stimulation in the laser group. Immediately after the electrical stimulation with or without the laser application, DRG of the fourth to sixth lumbar spinal roots were excised. Immunohistochemical substance P staining and substance P-like immunoreactivity (SP-LI) quantification were done in the excised DRG. There was a statistically significant difference of SP-LI between the control group (14.9 +/- 5.02 pg/mg tissue) and the stimulated group (20.9 +/- 7.54 pg/mg tissue) (p < 0.05). There was no statistically significant difference between the control and the laser group (16.2 +/- 4.83 pg/mg tissue). These results suggest that the laser irradiation suppresses the excitation of the unmyelinated C-fibers in the afferent sensory pathway. PMID- 9366143 TI - [Clinical assessment of rotational digital angiography for the diagnosis of hepatocellular carcinoma]. AB - PURPOSE: The purpose of the present study was to investigate whether rotational digital angiography add new diagnostic informations concerning the localization and feeding artery of hepatocellular carcinoma. MATERIALS AND METHODS: Rotational digital angiography was performed in 100 patients with hepatocellular carcinoma. There are 70 males and 30 females, ranging in age from 40 to 81 years. At first, abdominal anterior-posterior digital subtraction angiography was performed in C arm system using 12/9/7 inch I.I.-TV camera. After that, rotational digital angiography was carried out using SF-VA 100 system in all patients. In the processing of images, the pulse modes were taken during 360 degrees transverse rotation of the X-ray system at a speed of 4.8 sec. The pictures were displayed in real time on a CRT screen with high resolution, and 3 D images were observed. RESULTS: New diagnostic informations concerning the localization and the feeding artery of the tumor were added in 20 patients using this rotational digital system. The tumors in segment 7/8 (n = 10) were clearly visualized by -90.0 degrees and 90.0 degrees to 135.0 degrees, while tumors in segment 4 (n = 5) were revealed by -45.0 degrees, 49.0 degrees and 60.0 degrees. On the basis of this information, segmental transcatheter arterial embolization could be performed. CONCLUSION: The device has, therefore, been found to be of great value in diagnosing hepatocellular carcinoma, particularly for the feeding artery and the localization of the tumor. PMID- 9366144 TI - Sonographic appearance of hemorrhagic ovarian cyst with acute abdomen by transvaginal scan. AB - Hemorrhagic ovarian cyst (HOC) which is one of the functional cysts, is often involved in acute abdomen leading to laparatomy intervention. The reason for this mainly lies in the fact that it is easily misdiagnosed as an organic mass because of the presence of lower abdominal pain and the variable appearance of ultrasonographic images at presentation. We analyzed 15 cases of HOC associated with acute abdomen, of which in 2 cases the disease was confirmed by laparotomy. The remaining 13 cases were followed-up clinically and by daily transvaginal sonography (TVS) from the first detection of the cyst until complete resolution. The TVS images showed a variety of changes; however, when the images or their magnified views were observed precisely, important diagnostic characteristics were found which were classified into 3 categories: type 1 images showed mixed hypoechoic and hyperechoic areas, the demarcation line between which appeared as a thin or thick septum-like echo of smooth formation; type 2 images showed hypoechoic background and vertical, horizontal, or lamellar thin or thick thread like echoes with an overall reticular-like or sponge-like pattern; and type 3 images showed an overall hyperechoic and solid pattern. Type 1 and 2 images occurred more frequent (93.3%), and only 1 case had a type 3 image. In all image types, septum-like or thread-like echoes were seen, TVS type 1 and 2 images showed a clear division into hyperechoic and other areas with the passing of time which was finally changed into a cystic pattern and disappeared. Severe lower abdominal pain was present for 1 to 3 hours in 12 cases (80%), 4 to 6 hours in 2 cases (13.3%), and 11 hours in 1 case (6.7%). Other characteristics of HOC may be its most frequent occurrence in the young age group (10 to 20 years old, 80.0%) and in the luteal phase (84.6%). With operative cases, histopathological diagnosis was HOC. The clinical and particularly TVS findings described in the present study are of significant value in differential diagnosis of HOC with acute abdomen from other disorders presenting with acute abdomen. PMID- 9366145 TI - [The effect of FK 506, an immunosuppressant, on cerebral infarction volume in focal cerebral ischemia in rats]. AB - The effect of FK 506, an immunosuppressant which is widely used in the transplantation of liver, kidney and bone marrow, on cerebral infarction volume in transient focal ischemia was investigated. Focal cerebral ischemia was produced by 2 h occlusion of the left middle cerebral artery in rats. FK 506 (0.3 mg/kg body weight) and vehicle were administered intravenously immediately after induction of cerebral ischemia. After 24 h reperfusion the rats were sacrificed and brain infarct volume and edema volume were determined. The FK 506 treatment group showed a significantly reduced infarct volume in the cerebral cortex when it was compared with the vehicle treatment group, but infarct volume was not significantly reduced in the striatum which was the ischemic core in this focal ischemia model. However, FK 506 did not reduce the edema volume significantly. These results suggest that the reduction of infarct volume is a result of the neuroprotective effect of FK 506. This immunosuppressant may be useful in the treatment of cerebral infarction. PMID- 9366146 TI - Effects of maternal infection on prostaglandin production and uterine contraction in late-gestation pregnant goats. AB - The main objective of this study was to evaluate the relationship between maternal infection induced by pyrogen administration and the changes in maternal and fetal plasma levels of prostaglandin E2 (PGE2) and F 2 alpha (PGF 2 alpha) and uterine contraction. We administered one mg of pyrogen (E. coli endotoxin) into the maternal femoral vein; then then the changes in maternal and fetal core temperatures, plasma levels of PGE2, [PGE2] and PGF 2 alpha, [PGF 2 alpha]. pO2, pCO2, pH and maternal uterine contractions were measured in late-gestation pregnant goats (n = 8). Maternal and fetal core temperatures were elevated significantly 30 min after pyrogen administration (p < 0.05), reached their peak levels after 3 hours, and after 5 hours mean core temperatures returned to levels indistinguishable from initial control. Maternal plasma [PGE2] and [PGF 2 alpha] increased to 4318 +/- 321 pg/ml after 1 hour and to 670.8 +/- 58.4 pg/ml after 3 hours respectively (p < 0.05). Fetal plasma [PGF 2 alpha] increased significantly (p < 0.05) to 811.0 +/- 64.0 pg/ml after 1 hour; however, plasma [PGE2] did not change throughout the study. Periodic uterine contractions appeared after 3 hours and disappeared after 5 hours. These results suggest that pyrogen induces the elevation of maternal and fetal core temperatures and prostaglandin production, and that eventually causes uterine contractions. PMID- 9366147 TI - [Measurement of regional cerebral blood flow and glucose utilization in rat brain under chronic hypoperfusion conditions following bilateral carotid artery occlusion. Analyzed by autoradiographical methods]. AB - OBJECTIVE: Although the pathology of chronic hypoperfusion in rat following bilateral carotid artery occlusion has been documented, long term changes in cerebral blood flow and metabolism have not been reported. In this study regional cerebral blood flow (rCBF) and regional glucose utilization (rCGU) were analyzed by autoradiographical methods, pathological observation of the brains was also conducted. METHODS: Male Wistar rats aged 12 weeks were anesthetized and the bilateral carotid arteries were occluded. Physiological parameters, ABG, MABP, and rectal temperature were measured before and through occlusion. After 2 days, 1, 4, and 8 weeks and controls of rCBF (Sakurada) and rCGU. (Sokoloff) were measured (n = 6). Evaluated regions included frontal cortex (Fcor), parietal cortex (Pcor), temporal cortex (Tcor), occipital cortex (Ocor), genu corpus callosum (gCC), corpus callosum (CC), splenium corpus callosum (sCC), caudate putamen (CPu), globus pallidus (GP), internal capsule (IC), thalamus (Thal), hippocampus CA 1 (CA 1), hypothalamus (HypoTh), amygdal (Amygd), and substantia nigra (SNR). In separate animals (n = 3) tissue sections were stained using Kluver-Barrera (KB) and Hematoxylin-Eosin (HE), and pathological changes were observed. RESULTS: After 2 days the rCBF values were significantly reduced to 33 58% of control values in the Fcor. Pcor, Tcor, Ocor, gCC, CC, sCC, CPu, GP, JC, and Amygd. The reductions were observed from the 2nd day to the 1st week. From the 1st week to the 4th week values began to recover to control levels. However, after 4 weeks they were still significantly reduced in the Ocor, gCC, CC, sCC, GP, IC, and SNR (51-63%). After 8 weeks, the rCBF values in the areas except white matter, CPu, GP, and Ocor, etc., recovered to approximately 90% of control levels. However, in the Ocor, gCC, CC, sCC, CPu, GP, and IC, they were still 70 89% of control levels. After 2 days the rCGU values were reduced to 56-95% (except Amygd) in the measured regions, although not as reduced as the rCBF levels. From the 2nd day to the 1st week, the rCGU values were reduced further and after 1 week the rCGU values were significantly reduced to 39-69% in the Fcor, Pcor, Tcor, Ocor, gCC, CC, sCC, CPu, GP, IC (Lt), Thal (Rt), Amygd, and SNR From the 1st week to the 4th week, the values began to recover to control levels. After 4 weeks, rCGU improved to approximately 90-100% of controls, and remained at that level through 8 weeks occlusion. Rarefaction of the myelinated fibers was observed in the white matter from the 1st week to the 4th week in the KB stained sections, while little change in cortex was observed throughout 1st to 8th week. CONCLUSION: In this chronic hypoperfusion model rCBF remained depressed after 8 weeks in the Ocor, white matter, and basal ganglia, and rarefaction of the white matter was observed. These results indicate that this model is suitable for the study of chronic cerebral hypoperfusion. PMID- 9366148 TI - External high-frequency oscillation for hypercapnia after upper abdominal surgery. AB - The purpose of this study was to evaluate the efficacy of external high-frequency oscillation (EHFO) in patients with hypercapnia following upper abdominal surgery. Seven patients were ventilated with EHFO for 2 hr at 60 oscillations/min, with cuirass pressures of 36 cm H2O (-26 to +10), and an inspiratory to expiratory ratio of 1:1. Blood gases and cardiac functional parameters were examined during the 2 hr on EHFO. Pulmonary functional parameters were analyzed prior to the institution and after the termination of EHFO. PaCO2 significantly decreased from 61 +/- 8 mmHg to 48 +/- 7 mmHg after 10 min on EHFO (p < 0.01). PaO2 significantly increased from 74 +/- 10 mmHg 95 +/- 26 mmHg after 1 hr on EHFO (p < 0.01). The heart rate decreased significantly from 108 +/- 27 beats/min to 101 +/- 24 beats/min after 30 min on EHFO (p < 0.05). The FEV1 and FVC significantly increased from 1.09 +/- 0.54 L to 1.50 +/- 0.46 L (p < 0.01) and from 1.90 +/- 0.74 L to 2.18 +/- 0.60 L (p < 0.05), respectively. The other parameters of lung function also significantly improved after the termination of EHFO. The significant changes in all of the pulmonary functional parameters continued for 1 hr after the termination of EHFO. EHFO is an effective method of gas exchange which is associated with earlier return to preoperative lung function. PMID- 9366149 TI - 10-year survival rate in 92 patients with invasive bladder carcinoma treated by bladder sparing methods. AB - The 10-year survival rate was evaluated in 92 patients with invasive bladder cancer (stages T 2 to 4) who were treated between 1966 and 1985 using bladder sparing methods such as intravesical instillation of antineoplastic agents, transurethral resection, partial cystectomy, arterial infusion chemotherapy, radiation and embolization of the internal iliac artery. The overall 5-year and 10-year survival rates were 68.1% and 53.9% respectively at a median follow-up period of 60 months. The 10-year survival rate for patients with clinical stage T 2, T3a, T3b and T 4 were 83.7%, 58.9%, 50.8% and 0%, respectively. Our data were comparable or superior to those following radical cystectomy combined with pre- and post-operative radiation or chemotherapy. In conclusion, our bladder-sparing conservative method is thought to be an alternative treatment for advanced bladder cancer and provides a favorable survival rate as well as an improved quality of life with preservation of bladder function. PMID- 9366150 TI - [Apoptosis and its related diseases. Introduction for the symposium]. PMID- 9366151 TI - [Apoptosis mediated by Fas and its related diseases]. PMID- 9366152 TI - [Mechanism of apoptosis induced by the Bax protein]. PMID- 9366153 TI - [Neurotrophic factor and neuronal apoptosis]. PMID- 9366154 TI - [Neuronal apoptosis inhibitory protein NAIP and its related nerve degenerate disorder]. PMID- 9366155 TI - [Renal injury and apoptosis]. PMID- 9366156 TI - [Helicobacter pylori infection and gastroduodenal diseases. From the point of view of surgery]. PMID- 9366157 TI - [Experience of treatment for giant cell tumor of the upper tibia]. PMID- 9366159 TI - [Clinical and laboratory findings associated with the severity of community acquired pneumonia]. AB - To clarify the clinical features of severe community-acquired pneumonia, we retrospectively studied 121 patients treated at our hospital. We divided the patients into three groups, based on the severity, of their disease. Patients were put in the "mild" group (n = 56) if they recovered after treatment with antimicrobial agents only, they were put in the "moderate" group (n = 34) if the required oxygen therapy and recovered, and they were put in the "severe" group (n = 31) if they required mechanical ventilation. Age and underlying disease were recorded, as well as signs, symptoms, and laboratory data obtained during the first 24 hours after admission. The data indicated that the following nine findings were associated with the severity of disease: age of at least 65 years, an underlying disease of (31) the respiratory or central nervous system, dyspnea, a pulse rate of at least 90 beats per minute, a respiratory rate of at least 25 breaths per minute, an albumin concentration no greater than 3.5 g/dl, a blood urea nitrogen level of at least 20 mg/dl, a PaO2 no greater than 60 mmHg or an SaO2 no greater than 90%, and a high score on a scale of the extent of roentgenographic evidence of pulmonary infiltrates. Patients in whom these are found be managed carefully. PMID- 9366158 TI - [Effects of pimobendan on pulmonary hypertension in patients with chronic pulmonary emphysema]. AB - Pimobendan is a positive inotropic agent that dilates blood vessels and sensitizes the myocardium to calcium. We studied the clinical usefulness of single oral doses of pimobendan (2.5 mg) in 8 patients with pulmonary hypertension caused by chronic pulmonary emphysema. We measured the short-term effects of pimobendan on pulmonary hemodynamics and gas exchange. Pimobendan significantly decreased mean pulmonary artery pressure from 23.4 +/- 3.4 to 18.5 +/- 2.5 mmHg, and total pulmonary resistance from 383 +/- 111 to 281 +/- 81 dyne.sec.cm-5, while oxygen delivery and cardiac output increased significantly (oxygen delivery: from 81.8 +/- 10.2 to 93.5 +/- 16.2 ml O2/min. cardiac output: from 4.98 +/- 0.76 to 5.77 +/- 1.49 l/min, means +/- SD). Systemic vascular resistance was not significantly reduced. The ratio of pulmonary to systemic vascular resistance was reduced, but not significantly. Arterial oxygen tension (PaO2) and arterial carbon dioxide tension (PaCO2) did not change significantly. These results indicate that pimobendan may be useful in the treatment of patients with secondary pulmonary hypertension. PMID- 9366160 TI - [Results of a questionnaire about smoking distributed at the 36th annual meeting of the Japan Society of Chest Diseases]. AB - To gather data about smoking habits among members of the Japan Society of Chest Diseases, a questionnaire was distributed during the 36th annual meeting. A total of 2411 out of 3725 questionnaires were returned (65%). The percentage of smokers was 23%. Smoking was prohibited in the hospitals of 281 respondents (8%). Seventy nine percent reported that patients smoking areas were separated from patients' non-smoking areas, but only 41% reported that physicians' smoking areas were separated from physicians' non-smoking areas. Tobacco was being solid in over 50% of the hospitals represented, either via vending machines or through hospital retail stores. However, 79% of the respondents indicated that hospitals should be smoke-free. Questions of ethics in medicine are highlighted by this questionnaire. The obvious issues involved are whether or nor both patients and physicians should be required to stop smoking in health-care facilities. The larger issue is the degree and method by which the Japan Society of Chest Diseases should involve itself actively in smoking reform for the sake of society in general. PMID- 9366161 TI - [Chronic eosinophilic pneumonia associated with high concentrations of interleukin-5, -6, and granulocyte colony stimulating factor in serum and in pleural fluid]. AB - A 44-year-old Japanese man who had suffered from bronchial asthma since childhood was given the diagnosis of chronic eosinophilic pneumonia because of his symptoms, chest roentgenographic findings, and the results of a transbronchial lung biopsy. At the time of the onset of the disease, the pleural effusion contained 73% eosinophils. Symptoms were relieved and the laboratory findings returned forward normal after a short course of high-dose corticosteroids. The concentrations of IL-5, IL-6, and G-CSF in pleural fluid and in serum were very high; the concentrations of these cytokines were 3 times to 35 times higher in pleural fluid than in serum. In contrast, no IL-3 or GM-CSF was detected in any of these samples. The precise etiology of chronic eosinophilic pneumonia is still unclear, but this case suggests that inappropriate production of IL-5, IL-6 and G CSF in the lung play a pivotal role in this disease. Inhibition of the production of these cytokines may be another therapeutic approach to this disease. PMID- 9366162 TI - [Acute eosinophilic pneumonia associated with aspirin]. AB - A 21-year-old man was admitted to our hospital with acute progressive dyspnea and a high fever. He had started smoking 6 weeks before admission. A chest radiograph showed diffuse infiltrates with Kerley B lines and bilateral pleural effusions. There was no evidence of infection. His condition improved rapidly and without medication. On admission the concentrations of interleukin-5 in bronchoalveolar lavage fluid and in blood were high, but they were normal one week later. Acute eosinophilic pneumonia was diagnosed. A positive result of a lymphocyte stimulation test indicated that the development of symptoms was closely associated with ingestion of aspirin. We know of no previous report of acute eosinophilic pneumonia associated with aspirin. PMID- 9366163 TI - [Mycetoma-forming pulmonary nocardiosis and endobronchial polypoid lesion]. AB - A 46-year-old man was admitted to the hospital for evaluation of a dense infiltrative shadow in the right middle lung field. Bronchoscopic examination revealed a polypoid lesion in the right middle-lobe bronchus (Bb11(5)). Examination of a biopsy specimen showed a lump with many Nocardia asteroides bacteria. The response to chemotherapy, which included sulfomethoxazole, was poor, and therefore a right middle lobectomy was done. Three mycetomas were found inside the ectatic bronchi in the S5 area. Pulmonary Nocardia mycetoma is rare. PMID- 9366164 TI - [A patient with bronchial asthma and mucoid impaction who presented with a high concentration of carcinoembryonic antigen in serum]. AB - We encountered a patient with bronchial asthma and mucoid impaction who presented with a high concentration of carcinoembryonic antigen (CEA) in serum. The patient was a 46-year-old woman. One year after resection of a uterine myoma and an ovarian cyst, examination of serum revealed a high concentration of CEA (24.1 ng/ml). Further examination revealed no evidence of malignant disease, but an abnormal shadow was seen on a chest X-ray film, and was thought to be compatible with mucoid impaction. Fiberoptic bronchoscopy revealed mucoid impaction in the right lower-lobe bronchus. The concentration of CEA in bronchoalveolar lavage fluid was also high (6100 ng/ml). Lavage was done five times and the impaction was removed completely. The concentrations of CEA in serum and in bronchoalveolar lavage fluid decreased to 3.4 ng/ml and 621.9 ng/ml, respectively. PMID- 9366165 TI - [Pulmonary actinomycosis resembling an anterior mediastinal tumor]. AB - A 25-year-old, previously healthy man was referred to us because of fever, left sided chest pain, and an abnormal mass shadow at the left pulmonary hilum on chest X-ray films. Laboratory tests and fiberoptic bronchoscopy revealed no abnormality. Thoracotomy was done because a mediastinal tumor was suspected. Surgery revealed that the left lingula was atelectatic and that the mass was in the left S4, not in the mediastinum. Pathological examination of tissue from the partially resected lung showed sulfur granules, and a diagnosis of pulmonary actinomycosis was made. At least 80 cases of pulmonary actinomycosis were reported in Japan between 1963 and 1995. Pulmonary actinomycosis is most common among men in the fifth and sixth decades of life, and almost all patients have oral disease. Pulmonary actinomycosis is often difficult to distinguish from lung cancer, because both appear as mass shadows on X-ray films, and almost all cases of pulmonary actinomycosis are diagnosed by thoracotomy. PMID- 9366167 TI - [Three cases of thymic hyperplasia associated with hyperthyroidism]. AB - We encountered three cases of thymic hyperplasia associated with hyperthyroidism. Case 1 was in a 35-year-old woman; a chest CT scan showed an anterior mediastinal mass and right-sided pleural effusion, which suggested the presence of a thymoma Case 2 was in a 21-year-old man who complained of palpebral ptosis and also had myasthenia gravis (Osserman type I). Case 3 was in a 47-year-old woman; a chest CT scan showed thymic hyperplasia and mediastinal lymphadenopathy. In all cases, anti-thyroid medication was given first, because of the associations with hyperthyroidism. Moreover, in cases 1 and 2 no tumor was found, and only hyperplasia was detected in the thymus, although both patients underwent extended thymectomy. Furthermore, surgery was not effective against the hyperthyroidism (anti-thyroid medication could not be withdrawn or reduced). In cases 2 and 3, thymic hyperplasia, as seen on chest CT scans, resolved as thyroid function was normalized by anti-thyroid medication. The pretracheal lymphadenopathy seen in case 3 also resolved. Thymic hyperplasia may have been a result, not a cause, of hyperthyroidism. When we encounter patients with thymic masses and hyperthyroidism, we should give anti-thyroid medication and observe the thymus for some time before resorting to surgery. PMID- 9366166 TI - [Use of BiPAP during weaning from mechanical ventilation in a patient with chronic obstructive pulmonary disease and acute respiratory failure]. AB - In a 65-year-old man with chronic obstructive pulmonary disease and acute respiratory failure, bi-level positive airway pressure device (BiPAP) was used as part of weaning from mechanical ventilation. As an outpatient, he had had dyspnea of grade V (Hugh-Jones) and was hypercapnic (PaCO2 of 70 torr) and hypoxemic (PaO2 of 60 torr), while he was receiving oxygen at 2 L/min via nasal cannula. Acute respiratory failure developed due to pneumonia, and mechanical ventilation was begun. However, he could not be weaned with a standard weaning technique (T piece). On the fifth day of mechanical ventilation, he was extubated and treatment with BiPAP was begun. He did not complain of dyspnea even though PaCO2 did not decrease, which indicates that BiPAP reduced the work of breathing. Use of BiPAP might make reintubation unnecessary when acute ventilatory failure develops soon after extubation in patients with COPD. PMID- 9366168 TI - [Necrotizing sarcoid granulomatosis diagnosed by video thoracoscopic lung biopsy]. AB - A 28-year-old woman was admitted to our hospital because of chest pain. A chest roentgenogram and a chest computed tomogram revealed many nodular shadows on both sides. Examinations of specimens obtained by and by transbronchial lung biopsy during fiberoptic bronchoscopy were not diagnostic, and therefore video thoracoscopic lung biopsy was done. The lung lesion was characterized by aggregates of epithelioid cell granulomas, along with granulomatous and necrotizing angitis. We therefore diagnosed necrotizing sarcoid granulomatosis, and began to administer prednisolone. The nodular shadows disappeared within four weeks. In this case video thoracoscopic lung biopsy was useful in the diagnosis of necrotizing sarcoid granulomatosis in the lung. PMID- 9366169 TI - [Primary pulmonary lymphoma presenting as an endobronchial polypoid tumor]. AB - A 58-year-old woman because of coughing and an abnormality on a chest renggenogram was referred to our hospital. A chest X-ray film and a computed tomogram revealed atelectasis of the right lower lobe and a round tumor in the left lower lobe. Fiberoptic bronchoscopy revealed an endobronchial polypoid tumor in the intermediate bronchus, which completely obstructed the orifice of the right lower-lobe bronchus. Microscopical examination revealed B-cell diffuse, large, non-Hodgkin's lymphoma. No extrapulmonary lesion was found, and therefore primary pulmonary non-Hodgkin's lymphoma was diagnosed. Chemotherapy resulted in rapid and complete regression of the tumor, which was confirmed endoscopically and histologically. The patient was still in complete remission 8 months after the end of chemotherapy. There have been no additional interventions. PMID- 9366170 TI - [Microscopic polyangiitis and pulmonary fibrosis in a patient who died of Candida pneumonia and intra-alveolar hemorrhage]. AB - A 74-year-old man was admitted to our hospital because of edema of the lower legs, fever, and increasing fatigue. Laboratory evaluation revealed proteinuria, microhematuria, leukocytosis, thrombocytosis, anemia, a high level of C-reactive protein. A test for myeloperoxidase-antineutrophil cytoplasmic antibodies was highly positive. Microscopic polyarteritis nodosa was diagnosed and therapy with prednisolone was begun. Examination of a renal biopsy sample showed necrotizing crescentic glomerulonephritis. A chest roentgenogram and CT scan disclosed bilateral basilar interstitial changes. Six months later, the patient was admitted again because of disturbance of consciousness, malnutrition, and hyponatremia. After admission, alveolar infiltrates developed in the right lung and the patient died on the 5th hospital day as a result of respiratory failure. An autopsy revealed Candida pneumonia of the right lung and massive intra alveolar hemorrhage, which was believed to have caused the respiratory failure. Other findings were usual interstitial pneumonia, cellular small-vessel angiitis in the lungs, and healed angiitis in the kidneys and liver. In this case of microscopic polyangiitis and chronic interstitial pneumonia, steroid therapy was effective against the angiitis, but the patient died of an opportunistic infection and alveolar hemorrhage. PMID- 9366171 TI - [Two patients with summer-type hypersensitivity pneumonitis in Nagano Prefecture]. AB - We encountered two patients with summer-type hypersensitivity pneumonitis that developed in Nagano Prefecture. Patient 1 was a 61-year-old man who had worked in warm and humid environments as painter. He was referred to our hospital because of fever, coughing and exertional dyspnea. Respiratory symptoms developed during work but were gone within in few weeks. Patient 2 was a 50-year-old housewife who was admitted to our hospital because of persistent coughing and a low-grade fever. In both patients, chest roentgenograms and computed tomograms showed bilateral, small, nodular and reticular shadows. Examination of a specimen obtained from patient 2 by transbronchial lung biopsy revealed alveolitis. In both patients, bronchoalveolar lavage fluid had low CD4/8 ratios, but in patient 1 the lymphocyte fraction was high and in patient 2 the neutrophil fraction was high. A steroid drug was given to patient 1 because of the patients symptoms and prolonged abnormal roentgenographic findings. Patient 2 reacted positively on a provocation test when returned to her house. Serum from both patients contained antibodies to Trichosporon mucoides and T. asahii. We know of no previous reports of summer-type hypersensitivity pneumonitis that developed in Nagano prefecture. PMID- 9366173 TI - [Iodine 123-labeled meta-iodobenzylguanidine myocardial scintigraphy in the cases of idiopathic Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy]. AB - A 20-25% rate of antemortem misdiagnosis of idiopathic Parkinson's disease (PD) suggests that it may be difficult to clinically differentiate PD from other degenerative diseases of the central nervous system, such as progressive supranuclear palsy (PSP) or multiple system atrophy (MSA). Iodine-123 meta iodobenzylguanidine ([123I] MIBG), an analogue of norepinephrine, is a tracer for functioning of sympathetic neurons. To investigate cardiac sympathetic function in PD, MSA, and PSP, [123I] MIBG myocardial scintigraphy was performed in 25 patients with PD, 25 patients with MSA, 14 patients with PSP, and 20 control subjects. In planar imaging studies, the heart-to-mediastinum average count ratio (H/M) was calculated for both early and delayed images. The mean value of H/M in patients with PD was significantly lower than in those with MSA, PSP, or no disease (p < 0.0001). Regardless of disease severity or intensity of anti parkinsonian pharmacotherapy, mean values for H/M were always low in patients with PD. The mean values of H/M in patients with MSA and PSP were significantly lower than in controls (p < 0.01). There was no significant difference between the mean value of H/M in MSA with orthostatic hypotension (OH) and that in MSA without OH, and also there was no significant difference between the mean value of H/M in MSA with striatonigral degeneration and that in MSA with olivopontocerebellar atrophy. Although the mean value of H/M in PSP with amitriptyline treatment was significantly lower than that in PSP patients without amitriptyline treatment (p < 0.005), there was no significant difference between the mean value of H/M in PSP patients without amitriptyline treatment and that in controls. There was no correlation between H/M and disease duration in those three akinetic-rigid disorders that we have studied here. Thus, PD may have an abnormality of cardiac sympathetic function which has not been detected by previous cardiovascular autonomic studies. Particularly in early stages, [123I] MIBG myocardial scintigraphy may help to differentiate PD from MSA and PSP. PMID- 9366172 TI - [Multivariate analysis of the problems of long-term levodopa therapy in Parkinson's disease]. AB - We investigated clinical features of adverse reactions to long-term levodopa therapy by the multivariate analysis. Dyskinesia, wearing off effect, on-off effect, mental symptoms, and frozen gait were noted in 29 (11.2%), 78 (30.0%), 17 (6.5%), 45 (17.7%), and 52 (20.0%), respectively, of 260 patients with Parkinson's disease to whom levodopa had been administered for over one year. In the statistical investigation by the multivariate analysis (quantification method type II), the age of initial levodopa therapy, the duration from the onset to the initiation of levodopa therapy, and the duration of levodopa therapy were not closely related to the development of any adverse reaction, while Hoehn & Yahr's stage and the dosage of levodopa had the most significant influence on the development of adverse reactions. Furthermore, concomitant use of amantadine hydrochloride produced an inhibitory effect on the development of dyskinesia. We conclude that early institution of levodopa therapy in Parkinson's disease may not be an important risk factor of adverse reactions. PMID- 9366174 TI - [A case of multiple sclerosis with galactorrhea-amenorrhea syndrome]. AB - Patients with multiple sclerosis sometimes show subthalamic lesions presenting syndrome of inappropriate secretion of ADH (SIADH), hypothermia, hyperprolactinemia, weight loss, and cachexia. Hyperprolactinemia also has been found in the patients with active systemic lupus erythematosus, because prolactin can be produced from human activated lymphocytes. We described a case of multiple sclerosis showing galactorrhea-amenorrhea syndrome with hyperprolactinemia. A 31 year-old woman showed a high level of prolactin in the serum (79.6 ng/ml) during remission stage 5 months after the onset of multiple sclerosis. She showed galactorrhea-amenorrhea syndrome 3 years later. She showed dysesthesia in her limbs, relapsing monoparesis, visual disturbance and Gd-enhanced plaques in Brain MRI for 6 years. She was admitted to our hospital on November 24, 1995. A neurological examination showed hyporeflexia of the upper extremities, hyperreflexia of the lower extremities, bilateral ankle clonus, truncal ataxia, and neurogenic bladder. Laboratory tests revealed increased level of serum prolactin, exaggerated secretion of serum prolactin after intravenous injection of 500 micrograms TRH, and marked suppression after oral administration of 2.5 mg bromocriptine. Brain MRI showed demyelinating lesions near the lateral ventricle, and cervical MRI (T2 image) showed high signal intensity lesions in the spinal cord from C2 to C5. In the previous case, galactorrhea-amenorrhea syndrome was found during the exacerbation stage of multiple sclerosis. Hyperprolactinemia may be caused from subthalamic lesions or by activated lymphocytes in multiple sclerosis. We considered that hyperprolactinemia and galactorrhea-amenorrhea syndrome in our patient might be caused from subthalamic lesions because lymphocytes were not activated during the remission stage of multiple sclerosis. PMID- 9366175 TI - [Neuropsychological analysis in 2 cases of infarction in the left precentral gyrus--with special reference to apraxia of speech and agraphia]. AB - It remains controversial whether agraphia can coexist in a case with apraxia of speech, and whether an apraxia of speech can be classified into a category of aphasia. We examined the presence of agraphia in 2 right-handed patients of apraxia of speech. Case 1 of mild agraphia showed an infarcted lesion in the left precentral gyrus extending to the neighboring white matter, which involving the arcuate fasciculus on MRI. Positron emission tomography (PET) indicated decrease of cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) in the infarcted lesion, but no decrease of CBF and CMRO2 in the Broca's area. In this case, agraphia was more conspicuous in "kanji" than in "kana" and severity of the agraphia was not correlated to that of speech disturbance on naming test. Case 2 without agraphia showed a small infarcted lesion in the left precentral gyrus, which did not extend to the deep white matter on MRI. Agraphia can coexist with apraxia of speech in a case with the lesion in the left precentral gyrus, in which the cortical lesion is relatively widespread or extends to the deep white matter. However, lack of etiological connection between the agraphia and the apraxia of speech was suggested. We could not confirm the location in the left precentral gyrus which is responsible for the agraphia. PMID- 9366176 TI - [Efficacy of nasal bi-level positive airway pressure ventilation in a patient with olivo-ponto-cerebellar atrophy suffering from sleep apnea syndrome]. AB - Sleep apnea with neuromuscular disorders has been successfully treated with bi level positive airway pressure ventilation (BiPAP), which, unlike continuous positive airway pressure ventilation (CPAP), creates pressure difference between expiratory and inspiratory phases. Hence if the respiration of patients stops longer than a pre-set duration, BiPAP can automatically force them to breath through a nasal mask. We report a 60-year-old woman with olivo-ponto-cerebellar atrophy (OPCA), whose mixed-type sleep apnea was difficult to treat with conventional CPAP. We therefore tried BiPAP on this patient at night. Nocturnal CO2 retention was nearly resolved, and unexpectedly daytime PaCO2 was also corrected with marked improvement of daytime somnolence. BiPAP is totally non invasive, and may be one of the most effective treatments in patients with OPCA suffering from sleep apnea. PMID- 9366177 TI - [A case of dystrophia myotonica with homozygous DM kinase abnormalities]. AB - We report a case of dystrophia myotonica (DM) in a 38-year-old man with homozygous DM kinase abnormality. His distal muscle strength was reduced moderately; muscle biopsy showed type 1 predominance and type 1 fiber atrophy. The patient's WAIS total IQ score was under 60. Since his childhood, his cognitive deficit has been more severe than his muscle weakness. MRI demonstrated many abnormal changes in the brain of this patient, but these changes were mild in comparison to the severity of his reduced cognition and low IQ. The relationship between mental dysfunction and DM kinase abnormalities is quite different from that seen in cases of heterozygous DM kinase abnormalities. This case demonstrated severe mental changes in spite of mild DM kinase abnormalities. We suspect the homozygous DM kinase abnormality to be a cause of the different clinical presentations of this patient. PMID- 9366178 TI - [A case of porencephaly with mirror movements: pathophysiological investigation by using long-latency long-loop reflex and dipole tracing method]. AB - We report a 42-year-old left-handed woman with congenital right hemiparesis and bilateral mirror movements in the hands. She had a porencephaly of the left hemisphere and the brain MRI demonstrated cortical and subcortical defect of the left hemisphere from Brodmann's area 6 to 40 including the left motor cortex. By electrical stimulation of the left median nerve at the wrist, N20 of the somatosensory evoked potential was recorded in the right postcentral gyrus by using the dipole tracing method. Long-loop reflexes from the bilateral thenar muscles were recorded and their latencies were almost the same. The stimulation of the right median nerve did not evoke N20, nor long-loop reflex. These electrophysiological findings suggest that the reorganization of the motor system made the right motor cortex to innervate bilateral hands, and caused bilateral mirror movements. In other words, the mirror movements managed to relieve the paralysis of the right hand though the damage of the left motor cortex was present. In the previous literature we are able to find hypotheses regarding the mechanism of mirror movements in congenital hemiparesis. Here we discussed about the reorganization of the motor system in the damaged brain. PMID- 9366179 TI - [A case of axonal form of Guillain-Barre syndrome associated with anti-GM1b IgG antibody following Penner 4 Campylobacter jejuni infection]. AB - A 41-year-old woman was admitted to the hospital because of diarrhea followed by progressive weakness of all extremities and dysphagia. On neurological examination, she showed facial diplegia, bulbar palsy, flaccid quadriplegia, and absence of all deep tendon reflexes in addition to Lasegue's sign. The Campylobacter jejuni Penner type 4 was isolated from the culture of stool. The test of anti-GM1b antibody (IgG) was positive in the serum. The protein content was elevated in the cerebrospinal fluid without pleocytosis. The studies of motor nerve conduction velocity showed a pattern of the axonal neuropathy. This is a case of Guillain-Barre syndrome presenting with the axonal neuropathy possibly due to the immune response directed to GM1b which is triggered by the Campylobacter jejuni Penner type 4 infection. PMID- 9366180 TI - [Isolated retrograde amnesia following viral encephalitis]. AB - We describe a patient who presented with isolated retrograde amnesia of 2-year duration after recovery from viral encephalitis. The patient was a 29-year-old right-handed male dentist and was admitted to our hospital with a complaint of generalized convulsion. Cerebrospinal fluid (CSF) showed mononuclear pleocytosis. Neuroradiological examinations (X-ray CT, MRI and 123I-IMP SPECT) revealed no significant abnormality. Immunological method showed no specific increase of viral antibody titers. However, with a tentative diagnosis of viral encephalitis, administration of acyclovir was started. After 3 weeks he became comprehensive, and several kinds of neuropsychological tests were performed. His intelligence and immediate memory were normal, and his procedural memory of dentist was intact. On the other hand, he could not recall any information about events, both personal and public, occurred within 2 years before the onset of present illness. His autobiographical memory disorder was also demonstrated using a series of weekly comic. In isolated retrograde amnesia following viral encephalitis like this case, memory of relatively short time duration, acquired prior to the onset of present illness, tend to be disturbed. PMID- 9366181 TI - [Uncoupling of cerebellar blood flow and metabolism in paraneoplastic cerebellar degeneration: report of a case]. AB - We report a 65-year-old woman with paraneoplastic cerebellar degeneration (PCD) who showed reduced cerebellar metabolism with preserved blood flow. She was admitted to Gunma University Hospital because of progressive gait and speech disturbances. Neurologic examination revealed nystagmus, dysphagia, explosive speech, reduced muscle tone in limbs, and marked truncal and limb ataxia, and mild hypesthesia in hands and feet. Cranial MRI demonstrated slight cerebellar atrophy. Laboratory findings disclosed high levels of serum CA19-9 and other tumor markers, and positive anti-Yo antibody, indicating that she had PCD. A specimen obtained from an axillary lymph node revealed metastasis of poorly differentiated adenocarcinoma, although systemic and vigorous checkup failed to find its origin. Cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were measured using positron emission tomography (PET) 15 months after the onset. CMRO2 was clearly decreased in the cerebellum, while CBF was almost normal. Moreover, PET with 2 18F-fluoro-2-deoxy-D-glucose (FDG) revealed that glucose metabolism was also reduced in the cerebellum. Single photon emission tomography using 99mTc-ethyl cysteinate dimer (ECD) showed a normal blood flow pattern in the whole brain. These results indicated that uncoupling of circulation and metabolism in the cerebellum of this patient. There are several reports showing uncoupling of cerebral perfusion and metabolism in ischemic disorders, encephalitis, mitochondrial diseases, brain tumors, epilepsy and Gaucher disease, although its pathophysiology is not elucidated. Because anti-Yo antibody evidently gives a suppressive influence on the cerebellar neurons, understanding the way the autoantibody acts may give a clue to the mechanism of reduced cerebellar metabolism with preserved perfusion in PCD. PMID- 9366182 TI - [A case of Guillain-Barre syndrome treated with plasma exchange and intravenous high-dose immune globulin]. AB - We describe a 69-year-old female with Guillain-Barre syndrome (GBS) whose paresthesia and weakness improved after plasma exchange (PE) and intravenous high dose immune globulin (i.v.I.G.). She felt a paresthesia in her right arm, and 7 days later she noticed right arm weakness followed by gait disturbance within 2 days. She received a series of 6 PEs, but paresthesia and weakness did not improve. Following the last PE trial of this series, she was treated by i.v.I.G. (0.4 g/kg) for 5 days. After i.v.I.G., paresthesia and weakness improved in a few days. After 2nd series of 6 PEs, she was able to walk. In this clinical course, the treatment of i.v.I.G. after PE seemed to be effective. This case raises the possibility that i.v.I.G. might be the treatment in GBS patients with insufficient effect of PE. PMID- 9366183 TI - [A case of progressive supranuclear palsy associated with bilateral vocal cord abductor paralysis]. AB - We report a 65-year-old male with progressive supranuclear palsy (PSP) who developed bilateral vocal cord abductor paralysis (VCAP). The patient was admitted to our hospital because of impaired gait. He was well until two years earlier, when he began to walk unsteadily. During the next two years, dysarthria and dysphagia developed and his gait worsened gradually. On admission, neurological examination showed impaired vertical and incomplete lateral gaze. His speech was slow and monotonous. Contractures were found in the neck muscles and elbows. The deep tendon reflexes were increased in the upper and decreased in the lower extremities. Babinski sign was negative. Snout and forced grasping reflexes were elicited. He showed marked bradykinesia. Magnetic resonance imaging revealed a midbrain tectum atrophy. Single photon emission tomography showed severe hypoper-fusion in the frontal cortex. No improvement was provided by the administration of levodopa-carbidopa, bromocriptine, droxydopa and amitriptyline. One month after admission, inspiratory stridor developed at night. The laryngofiberscopic examination demonstrated VCAP. An emergency tracheostomy relieved his respiratory distress. Although VCAP rarely occurs in neurodegenerative disorders other than multiple system atrophy, attention to VCAP should be required in PSP patients. PMID- 9366184 TI - [A case of malignant lymphoma with a metastasis to the lateral rectus muscle]. AB - We reported a 75-year-old woman with malignant lymphoma who had a metastasis to the right lateral rectus muscle. She was well until two months earlier, when a tumor in the left thigh began to enlarge. Ten days before admission, she noticed medial deviation of the right eyeball. Neurological examination showed the right esotropia with isolated paralysis of the right lateral gaze. She denied double vision. MR imaging demonstrated a swelling of the right lateral rectus muscle. Gallium scanning revealed abnormal accumulation in the right orbit and the left thigh. The tumor in the left thigh was histologically diagnosed as non-Hodgkin's lymphoma, diffuse large cell type. Discrete extraocular muscle metastasis is rare and unreported for malignant lymphoma. Reported cases of breast and thyroid cancers metastatic to the extraocular muscles did not develop diplopia similar to our case. The rapid growth of metastases to the extraocular muscles produces a large visual axes deviation, therefore no diplopia may be elicited. PMID- 9366185 TI - [Multiple solitary lesions in deep white matter in the early stage of Creutzfeldt Jakob disease. A case report]. AB - A 56-year-old housewife was admitted to our hospital because of involuntary movement on her left arm. Her neurological examination on admission showed mild weakness of her left arm and cerebellar ataxia. She developed periodic synchronous discharge on electroencephalogram and her cerebrospinal fluid revealed elevated level of neuron-specific enolase. Thereafter she developed dementia, followed by apallic state and diagnosed as having Creutzfeldt-Jakob disease (CJD). Interestingly, her MRI on admission revealed multiple solitary lesions in deep cerebral white matter, which were detected as high signal intensity by T2 weighed image. A few months later, these lesions tended to extend, and finally fused around the lateral ventricle in parallel with remarkable cortical atrophy. We excluded other diseases such as cerebrovascular disorders. Finally, we concluded the white matter change seen from early stage in this case may be the lesion associated with CJD, and the CJD case with early white matter changes has been seldomely described. PMID- 9366187 TI - [A case of adult-onset neurenteric cyst presenting as chronic progressive muscular atrophy in lower legs]. AB - A 50-year-old man was admitted, because of motor weakness of the lower limbs, dysesthesia of the left lower extremity, and anuresis. He had an episode of pain in his gluteal region 17 years ago, and then, no abnormalities were detected including myelography in a hospital, followed by slowly progressive muscular atrophy of his lower legs. At 50 years of age, dysuria appeared. He was diagnosed as having neurogenic bladder by urologists, and was admitted to our hospital. On admission, abnormal neurologic findings included: severe muscular atrophy in his lower legs, pes cavus, dysesthesia at the left S1 level, and autonomic bladder. Magnetic resonance imaging (MRI) showed mass lesion involving lower conus and cauda equina. After resection, pathological study revealed the mass was a neurenteric cyst. It is said that the neurenteric cyst causes an asymmetrical and sequential loss of specific neurological functions, with a subsequent return of these functions in the reverse order. That mechanism is not clear. However, in our case, the course of the illness was slowly progressive. We speculate that, because of the cyst's adhesion to cauda equina and perforation through the cyst by a nerve root, the cyst was fixed and caused slowly progressive neurological deficits in proportion to increase of the cyst's size. Our report suggests that a neurenteric cyst, involving the lower conus and cauda equina, can produce severe muscular atrophy in the lower legs. PMID- 9366186 TI - [Molecular analysis of a patient with carnitine palmitoyltransferase II deficiency]. AB - Carnitine palmitoyltransferase (CPT), one of the key enzymes of beta-oxidation, translocates long-chain fatty acids from the cytosolic compartment into the mitochondrial matrix to undergo beta-oxidation. Recently, the CPT system has been characterized to consist of two distinct mitochondrial membrane-bound enzymes, CPT I, located on the inner side of the outer mitochondrial membrane, and CPT II, located on the inner mitochondrial membrane. We have investigated a Japanese patient with muscular manifestations who was previously reported as CPT deficiency. Enzymatic analysis of her cultured lymphoblasts revealed that CPT II activity was reduced to 5.8%, indicating that the patient suffered from CPT II deficiency. Molecular analysis identified a missense mutation, a glutamate (174) to-lysine substitution (E174K), in the CPT II cDNA. The patient was homozygous for the mutation. The presence of the mutation was confirmed by PCR-RFLP with a mismatched primer to generate Mbo II recognition sequence at the mutation site. It has been reported that CPT II deficiency manifests as two different clinical phenotypes: a muscular form and a hepatocardiomuscular form. To our knowledge, this is the first case of CPT II deficiency with muscular symptoms to be characterized by molecular analysis in Japan. PMID- 9366188 TI - Expanded Programme on Immunization (EPI). Safety and efficacy of measles vaccine/vitamin A supplementation. PMID- 9366189 TI - [Degradation signal of proteins]. PMID- 9366190 TI - [Post-translational modification by ubiquitin]. PMID- 9366191 TI - [Degradation system for cellular functional molecules]. PMID- 9366192 TI - [Sequence motifs in proteasome subunits and their possible functions]. PMID- 9366194 TI - [Calpain: an approach using Drosophila melanogaster]. PMID- 9366193 TI - [Calpain super family and its interacting-proteins]. PMID- 9366195 TI - [Calpastatin: molecular mechanism of calpain inhibition]. PMID- 9366196 TI - [The endosomal-lysosomal system: new roles in protein degradation]. PMID- 9366197 TI - [Proline specific peptidases]. PMID- 9366198 TI - [Control of cellular functions by ATP-dependent proteases in prokaryotes]. PMID- 9366199 TI - [ATP-dependent protein degradation system in mitochondria]. PMID- 9366200 TI - [Tricorn protease]. PMID- 9366201 TI - [The mechanism of cyclin degradation]. PMID- 9366202 TI - [Problems of proteolysis in the function of Mos]. PMID- 9366203 TI - [The role of ubiquitin ligases in the cell proliferation]. PMID- 9366204 TI - [Regulation of cell cycle by proteasome in yeast]. PMID- 9366205 TI - [Cell adhesion and proteases]. PMID- 9366206 TI - [Proteases participating in the metamorphosis of insects]. PMID- 9366207 TI - [Physiological functions of proteases in oocyte maturation, fertilization and development]. PMID- 9366208 TI - [Cell growth-factor activity of tissue inhibitors of metalloproteinases (TIMPs)]. PMID- 9366209 TI - [Ligand-induced polyubiquitination of receptor tyrosine kinases]. PMID- 9366211 TI - [Death signaling by caspase family protease]. PMID- 9366210 TI - [A novel serine protease responsible for proteolytic activation of hepatocyte growth factor in response to tissue injury]. PMID- 9366212 TI - [Apoptosis in embryogenesis and diseases]. PMID- 9366213 TI - [Cell death and proteases]. PMID- 9366214 TI - [Vacuole as protein degradation system in yeast]. PMID- 9366215 TI - [Vacuolar processing enzymes responsible for regulation of vacuolar function of plants]. PMID- 9366216 TI - [Protein degradation in endoplasmic reticulum]. PMID- 9366217 TI - [Oryzacystatin-oryzain relation: from biological dissection to applications]. PMID- 9366219 TI - [Processing of mitochondrial protein precursors]. PMID- 9366220 TI - [Molecular mechanisms for processing of endogenous antigens]. PMID- 9366218 TI - [Activation of proprotein and kexin-family processing protease]. PMID- 9366221 TI - [MHC class II restricted antigen presentation]. PMID- 9366222 TI - [Processing and presentation of exogenous antigen by cathepsin B]. PMID- 9366223 TI - [The role of matrix metalloproteinases in cancer invasion and metastasis]. PMID- 9366224 TI - [Alzheimer's disease]. PMID- 9366225 TI - [Role of cellular proteases and protease inhibitor in viral infection]. PMID- 9366226 TI - [Neurodegenerative diseases as proteolytic disorders: brain ischemia and Alzheimer's disease]. PMID- 9366227 TI - [Muscular dystrophy]. PMID- 9366228 TI - [Structural and functional characterization of periodontal pathogenic cysteine proteinases from Porphyromonas gingivalis]. PMID- 9366229 TI - [Interaction trap using yeast two-hybrid system]. PMID- 9366230 TI - [Genetic dissection of protease and signal transduction network]. PMID- 9366231 TI - [Structural studies on proteases by protein crystallography]. PMID- 9366232 TI - [Structure and function relationship of cystatin A elucidated by NMR]. PMID- 9366233 TI - [Structural analysis of protease-inhibitor system using graphics]. PMID- 9366234 TI - [New specific inhibitor design by computer-graphics of protease structure]. PMID- 9366243 TI - Cross-talk between secretory phospholipase A2 and cytosolic phospholipase A2 in rat renal mesangial cells. AB - Incubation of rat glomerular mesangial cells with potent proinflammatory cytokines like interleukin 1beta, (IL- 1beta) triggers the expression of a non pancreatic secretory phospholipase A2 (sPLA2) and increases the formation of prostaglandin E2. We show here that sPLA2 acts in an autocrine fashion on mesangial cells and induces a rapid activation of protein kinase C (PKC) isoenzymes delta and epsilon and of p42 mitogen-activated protein kinase (MAPK), two putative activators of cytosolic phospholipase A2 (cPLA2). sPLA2 also activates Raf-1 kinase in mesangial cells which integrates the signals coming from PKC for further processing along the MAPK cascade. Subsequently a phosphorylation and activation of cPLA2 is observed, thus arguing for a cross talk between the two classes of PLA2. Pretreatment of cells with either the highly specific PKC inhibitor Ro-318220 or the highly specific MAPK kinase (MEK) inhibitor PD 98059 completely blocked the sPLA2-induced cPLA2 activation, indicating that both kinases are essential for the cross-talk between the two types of PLA2. The effect of sPLA2 is mimicked by lysophosphatidylcholine (LPC), a reaction product of sPLA2 activity. LPC stimulates PKC-epsilon, Raf-1 kinase and MAPK activation as well as cPLA2 activation with a subsequent increase in arachidonic acid release from mesangial cells. These data suggest that sPLA2 by cleaving membrane phospholipids and generating LPC and other lysophospholipids activates cPLA2 via the PKC/Raf-1/MAPK signalling pathway. Hence a network of interactions between different PLA2s is operative in mesangial cells and may contribute to the progression of glomerular inflammatory processes. PMID- 9366244 TI - Diacylglycerol partitioning and mixing in detergent micelles: relevance to enzyme kinetics. AB - For many of the enzymes that utilize or produce diacylglycerols, detergent mixed micelles are often used in assay systems to solubilize the lipophilic substrates or products. The assumption is often made that the diacylglycerol (DAG) is solubilized and well mixed throughout the population of micelles during the time course of the assay. In the present work the partitioning and exchange dynamics of diacylglycerols (from dihexanoyl-DAG to didecanoyl-DAG) in a variety of detergent micelles have been studied by NMR and fluorescence methods. In all detergents, the longer the DAG chain lengths, the more detergent is required for solubilization. However, efficiency of solubilization varies tremendously with Triton X-100 the most efficient (i.e. the least detergent is required), and deoxycholate the least efficient in solubilizing DAG. The mixing and exchange dynamics of pyrene-labeled DAG molecules in these micelles (measured by stopped flow fluorescence) were fastest for Triton X-100 and slowest with charged bile salt micelles. Of the detergent systems characterized, Triton X-100 appears to be the optimal detergent for use in assays of enzymes that interact with DAG (beta octylglucoside and diheptanoylphosphatidylcholine have good exchange dynamics, but higher amounts of these detergents are needed to solubilize DAG). Bile salt micelles provide the least solubilization and the slowest exchange kinetics (so slow that this could be a significant problem in some enzyme assays). This information on DAG behavior in micelles is discussed with respect to assays of an enzyme that generates DAG as product (phospholipase C) and one that uses DAG as substrate (DAG kinase). Although slow exchange of DAG occurs in some micelle systems, this does not appear to be a rate-limiting step in the kinetics for either of these enzymes. PMID- 9366245 TI - Hepoxilin A3 is oxidized by human neutrophils into its omega-hydroxy metabolite by an activity independent of LTB4 omega-hydroxylase. AB - Hepoxilin A3-methyl ester is taken up by intact human neutrophils where it is first hydrolyzed into the free acid which is subsequently converted into a single major metabolite. The structure of this metabolite was determined through mass spectral analysis of several derivatives, and through identity with an authentic compound prepared by chemical synthesis. The metabolite was identified as omega hydroxy-hepoxilin A3 showing that the epoxide functionality of the parent hepoxilin is not opened during incubation with human neutrophils. All attempts to investigate hepoxilin metabolism in broken cells, despite the presence of protease inhibitors (Aproteinin, PMSF, DFP) and supplementation with NADPH were unsuccessful. Metabolism of hepoxilin A3 required the intact cell, while parallel experiments with LTB4 as substrate demonstrated that this eicosanoid was metabolized into its omega-hydroxy metabolite regardless of whether intact or broken cell preparations were used provided that NADPH was present in the latter. Hepoxilin metabolism in intact cells was inhibited dose-dependently by CCCP (0.01 100 microM), a mitochondrial uncoupler, whereas LTB4 metabolism was unaffected by CCCP. This data suggests that metabolism of hepoxilin A3 occurs in intact human neutrophils through omega-oxidation, is likely located in the mitochondrial compartment of the cell (inhibition by CCCP) and is carried out by an activity that is independent of the well characterized, relatively stable microsomal LTB4 omega-hydroxylase. PMID- 9366246 TI - The apolipoprotein A-I/C-III/A-IV gene cluster: ApoC-III and ApoA-IV expression is regulated by two common enhancers. AB - Genetic, epidemiological and clinical evidence have clearly demonstrated the importance of the human apolipoprotein (apo) A-I/C-III/A-IV gene cluster in lipid metabolism and heart attack. The transcriptional regulation of these genes determines the level of the encoded proteins and therefore influences the concentration of triglycerides and cholesterol. Here, we analyze the existence of transcription control elements in the 6.6 kb apoC-III/A-IV intergenic region and their influence on the expression of both genes. Two main positive common control elements were found to modulate apoC-III and apoA-IV expression in HepG2 and in Caco-2 cells: the previously described apoC-III enhancer, located 0.8 kb upstream from the cap site of the gene, and a newly detected activating region located in the center of the intergenic sequence. The activity of both elements is highly increased by the hepatic and intestinal transcription factor HNF-4. Analysis of a 641 bp fragment containing the central element showed that it has the properties of a tissue-specific enhancer. Liver nuclear proteins interact with seven DNA binding sites present in this enhancer and HNF-4 specifically interacts with one of these sites. A third positive element, situated immediately upstream from the apoA-IV minimal promoter, is also activated by HNF-4; however, this element is not involved in apoC-III expression. In addition, two negative regions were identified, one located near the apoA-IV gene and the other one between the apoC III enhancer and the newly identified central enhancer. In conclusion, negative and positive control elements are located in the apoC-III/A-IV intergenic region, including two enhancers important for the expression of the two genes. These results add new evidence that common regulatory elements for the expression of the apoA-I, apoC-III and apoA-IV genes are interspersed throughout the cluster. PMID- 9366247 TI - Differential effects of sphingomyelinase and cell-permeable ceramide analogs on proliferation of Swiss 3T3 fibroblasts. AB - Metabolites of sphingomyelin, ceramide and sphingosine, have previously been implicated in cell growth regulation. Here we show that cell-permeable ceramide analogs and treatment with sphingomyelinase, which hydrolyzes sphingomyelin located on the outer leaflet of the bilayer, increase the progression of quiescent Swiss 3T3 fibroblasts through the S phase of the cell cycle leading to an increase in cell division. Although both potentiate the mitogenic effects of several growth factors [14], sphingomyelinase treatment antagonized the mitogenic effect of the tumor promoter, 12-O-tetradecanoylphorbol 13-acetate (TPA), while ceramide analogs had no effect, and sphingosine, a further metabolite of ceramide, potentiated the mitogenic effect of TPA. Concomitantly, sphingomyelinase, but not ceramide analogs, blunted the rapid increase in membrane-associated protein kinase C (PKC) activity induced by TPA without affecting the translocation of PKC alpha, delta, epsilon or zeta isoforms. Moreover, in contrast to sphingosine which activates phospholipase D (PLD) leading to an increase in phosphatidic acid levels, sphingomyelinase, but not ceramide analogs, reduced TPA-stimulated PLD activity. Our results suggest that the signaling pathways utilized by sphingomyelinase differ from those of cell permeable ceramide analogs, and both act differently than sphingosine. The differential effects of exogenous short-chain ceramide analogs and sphingomyelinase call for caution in using these analogs as tools to study the role of ceramide in diverse cellular functions. PMID- 9366248 TI - Activation of intestinal mitochondrial phospholipase D by polyamines and monoamines. AB - Intestinal mitochondria have a phospholipase D (PLD) activity which was stimulated by polyamines and monoamines resulting in the formation of phosphatidic acid (PA) from endogenous phospholipids. When stimulated by polyamines, mitochondrial PLD utilized endogenous phosphatidylethanolamine (PE) as substrate whereas stimulated by monoamines, both PE and phosphatidylcholine (PC) were hydrolysed. Stimulation of PA formation by spermine was enhanced by the presence of calcium. Since polyamines are known to alter the calcium transport by mitochondria and PA is known to possess an ionophore effect, stimulation of PA formation in mitochondria by polyamines suggests that polyamine-induced alteration in calcium homeostasis might involve a PA related mechanism. PMID- 9366249 TI - Peroxisome proliferator activated receptors in Atlantic salmon (Salmo salar): effects on PPAR transcription and acyl-CoA oxidase activity in hepatocytes by peroxisome proliferators and fatty acids. AB - A cDNA fragment which encodes salmon peroxisome proliferator activated receptor y (sPPARgamma) was amplified by PCR from the liver of Atlantic salmon (Salmo salar L.). The fragment was 627 bp long. The sequence of the amplified PCR product was similar to the PPARgamma of mouse and hamster. 59% of the bases were identical. Northern blot analysis of salmon liver mRNA showed that the amplified sPPARgamma fragment hybridised to three specific transcripts of lengths 1.6, 2.4 and 3.3 kb. Clofibric acid and bezafibrate, administered to salmon hepatocytes in culture, resulted in a 1.7-fold increase of the 1.6 kb sPPARgamma transcript. The activity of acyl-CoA oxidase also increased approx. 1.7-fold after administration of fibrates. These results indicate that PPAR is an important factor in mediating enzymatic response to fibrates in fish. PMID- 9366250 TI - Manipulation of lipid composition of rat heart myocytes aged in culture and its effect on alpha1-adrenoceptor stimulation. AB - The fatty acid composition of the phosphoinositides was evaluated in cultured neonatal rat cardiomyocytes during the aging-like process in vitro, comparing data obtained from control and gamma-linolenic acid supplemented cardiomyocytes. The response to alpha1 stimulation was evaluated in both control and supplemented cells to verify the relationship between the alterations of the phosphoinositide fatty acid composition concomitant to culture aging and the cell response to exogenous stimuli. Arachidonate level decreased as a function of age in all the phosphoinositides, which appeared to be more saturated as cells aged in culture. Inositol phosphate production in response to alpha1 stimulation decreased as cells aged in culture. Supplementation of culture medium with gamma-linolenic acid caused significant modifications in the fatty acid pattern of the phosphoinositides, which appeared less saturated than the corresponding fractions isolated from unsupplemented cells during the aging-like process. The modifications induced by the supplementation in the phosphoinositide fatty acid composition prevented the age-related reduction of inositol phosphate production upon stimulation. These results clearly indicate a major role for the lipid composition in determining the response to alpha1 stimulation, suggesting a nutritional approach to overcome some of the impairments of molecular events related to the process of aging. PMID- 9366251 TI - Polyunsaturated thia- and oxa-fatty acids: incorporation into cell-lipids and their effects on arachidonic acid- and eicosanoid synthesis. AB - EPA, DHA, C15SCH2COOH (n-3), C15SCH2COOH (n-6) and C18SCH2COOH (n-3) are extensively incorporated into phospholipids and triacylglycerol in rat hepatocytes after 24 h incubation with 80 microM fatty acid/derivative. Only traces of polyunsaturated 3-oxa fatty acids (C15OCH2COOH, C18OCH2COOH) were incorporated. C15-S-butyric acid (n-3) is a stronger inhibitor of delta6 desaturase in rat liver-microsomes than C15SCH2COOH (n-3), C15-S-propionic acid (n-3), EPA and DHA. It inhibits delta5-desaturase in a similar manner to EPA and DHA. Arachidonic acid and C15SCH2COOH, (n-6) are better substrates for PGH synthase than EPA and C15SCH2COOH, (n-3), showing the inhibitory effect of the n 3 bond. The n-3 polyunsaturated fatty acids, including the sulfur-substituted fatty acid derivatives, are poor substrates for PGH-synthase. However, they inactivate the PGH-synthase activity at least as efficiently as arachidonic acid. C15SCH2COOH (n-3), C15S(CH2)2COOH (n-3) and C18SCH2COOH (n-3) induce peroxisomal beta-oxidation more than EPA and DHA. PMID- 9366252 TI - Identification and characterization of a mouse protein kinase that is highly homologous to human integrin-linked kinase. AB - Integrin-linked kinase (ILK) is a recently identified human protein kinase that has been implicated in integrin-mediated signal transduction and tumorigenesis. We have identified a mouse molecule that is highly homologous to human ILK. The mouse ILK homologue protein is readily recognized by antibodies raised against the human ILK protein, and the gene encoding the mouse ILK homologue is widely expressed in mouse tissues. The mouse ILK homologue gene has been mapped to chromosome 7E1 band. A second locus in the mouse chromosome 9E1-3 region has also been detected with a mouse ILK homologue cDNA probe by fluorescence in situ hybridization, suggesting the possible existence of an ILK pseudo-gene or a family of ILK genes in the mouse. PMID- 9366253 TI - Inositol 1,4,5-trisphosphate receptor expression in odontoblast cells. AB - The cellular distribution of inositol 1,4,5-trisphosphate receptors was examined in rodent maxillary incisor teeth. In situ hybridization studies with a transmembrane probe of type I inositol 1,4,5-trisphosphate receptor indicated that this receptor/channel was highly expressed in odontoblast cells of incisor teeth. In contrast, very low labeling was observed in dental pulp. Northern analysis showed a message size of approximately 9.5 kilobases for this receptor, and demonstrated that type III inositol 1,4,5-trisphosphate receptor was expressed in incisor teeth. Immunocytochemical studies confirmed that types I and III inositol 1,4,5-trisphosphate receptors were both highly expressed in odontoblasts while very low expression was detected in dental pulp. Finally, antibodies that recognized alpha subunits of the Gq class of GTP binding proteins also stained odontoblasts. These results indicate that receptor-mediated regulation of calcium release through inositol 1,4,5-trisphosphate receptors may occur in odontoblasts of rat incisor teeth. These findings also suggest that inositol 1,4,5-trisphosphate receptor/channels regulate calcium flux in odontoblasts during mineralization of dentin, or in growth and differentiation of incisor tissue. PMID- 9366254 TI - Fission yeast dihydrolipoamide dehydrogenase gene is involved in G1/S cell cycle progression. AB - Using functional complementation with a Schizosaccharomyces pombe genomic library, we have isolated a clone complementing a G1/S phase progression defective mutant. The newly isolated temperature-sensitive mutant, cyj150, showed elongated morphology at a restrictive temperature of 36 degrees C and DNA content analysis of the mutant indicated a defect in cell cycle progression at the G1/S phase. Sequence analysis of the genomic and cDNA clones complementing this elongated phenotype at 36 degrees C show that it encodes a protein that has 50% amino acid identity with dihydrolipoamide dehydrogenase from Saccharomyces cerevisiae and garden pea. Alignment of the deduced amino acid sequence of S. pombe dihydrolipoamide dehydrogenase (dld1+) with glutathione reductase and mercuric reductase revealed extensive homologies throughout the primary sequence and protein structure, and contained amino acid sequences of the active site region conserved from prokaryote to higher eukaryote. Gene disruption and tetrad analysis showed that dld1+ is an essential gene for cell viability. Northern analysis indicates that transcriptional expression of this gene is not fluctuated according to the cell cycle. However, it is certain that malfunction of this Dld1 protein blocks the progression of cell cycle from G1 to S phase. The sequence of the dld1+ gene is available in EMBL/GenBank under Accession Number L40360. PMID- 9366255 TI - Expansion of the cellular content of ribonucleoside triphosphates induces cell shrinkage and KCl loss in Ehrlich ascites tumor cells and in Chinese hamster ovary cells. AB - The conversion to corresponding triphosphate derivatives of various ribonucleosides has been studied in Ehrlich ascites tumor cells and in Chinese hamster ovary cells under conditions that are optimal for cellular uptake of orthophosphate. The initial cellular uptake of orthophosphate is followed by a cellular loss of Cl- which might be consistent with a H2PO4-/Cl- exchange mechanism. Subsequent addition of ribonucleosides to the medium leads to cellular accumulation of the corresponding triphosphate and to a concomitant loss of KCl and to sustained cell volume reduction. The latter two events are quite unspecific with regard to the nucleobase moiety of the ribonucleoside triphosphate accumulated (adenine, guanine and purine being almost equally effective) and they depend in a rather simple way on the increase of the cellular content of these compounds. The KCl loss seems to depend on opening of the separate K+ and Cl- channels. The pharmacological profile of the putative ion channels could not be identified in spite of experiments with conventional blockers. In the case of purine riboside the accumulation of the corresponding triphosphate and concomitant loss of KCl and cell water may be followed by a regain of cell volume due to a continued purine riboside triphosphate accumulation, which apparently depends on the uptake of orthophosphate by cotransport with Na+ and which for osmotic reasons is accompanied by the uptake of water and hence volume increase. The possibility that the nucleoside triphosphate induced opening of a putative Cl- channel may be due to a direct effect of triphosphate on a channel protein is discussed. PMID- 9366257 TI - Ribonucleases and host defense: identification, localization and gene expression in adherent monocytes in vitro. AB - Several ribonucleases of the RNase A family function as antibacterial, anti parasitic and anti-viral agents. In this work, we have shown that mRNAs encoding five of the six known human ribonucleases of the RNase A family are expressed in cultured human monocytes, and that ribonucleases are released by adherent monocytes in culture. Using a polyclonal antiserum prepared against recombinant protein, we have detected one of these ribonucleases, RNase 4, in lysates of normal human peripheral blood monocytes, but not granulocytes or lymphocytes, by Western blotting. Subcellular localization by immunoelectron microscopy demonstrated the presence of RNase 4 in the cytoplasmic granules of isolated monocytes. Interestingly, mRNA encoding RNase 4 could not be detected in freshly isolated monocytes, emerging only after 16 h in culture, suggesting the possibility of de novo protein synthesis in association with monocyte differentiation. PMID- 9366256 TI - A novel dimeric oxovanadium (IV) species identified in Saccharomyces cerevisiae cells. AB - Saccharomyces cerevisiae cells stored oxovanadium (IV) ions in a dimeric form. In the late stationary phase Saccharomyces cerevisiae cells grown in rich medium containing concentrations of oxovanadium (V), orthovanadate from 12 to 18 mM, causing growth stasis, a dimeric oxovanadium (IV) species was identified by EPR spectroscopy. The EPR spectrum exhibited at 110 K the low-field forbidden deltaMs = +/-2 transition at g around 4 and the half-field deltaMs = +/-1 15-lines feature at g around 2 out of the presence of a triplet state by the coupling of the oxovanadium (IV) ions in a dimeric form. Hyperfine splitting of 75.2 x 10(-4) cm(-1) and an interionic distance of about 4.4 angstroms was calculated. The dimeric species was localized in the cellular cytoplasmic space. PMID- 9366258 TI - High concentrations of phosphatidylinositol-4,5-bisphosphate may promote actin filament growth by three potential mechanisms: inhibiting capping by neutrophil lysates, severing actin filaments and removing capping protein-beta2 from barbed ends. AB - Cell locomotion requires rapid growth of cortical actin filaments whose barbed ends are capped in the resting cell. Phosphatidylinositol-4,5-bisphosphate (PIP2) may play a critical role as an intracellular messenger in cytoskeletal rearrangement after stimulation. We have examined the effects of PIP2 micelles on the Ca2+-independent actin filament capping activity in high speed supernatants of neutrophil lysates which we had previously demonstrated to be almost entirely due to capping protein-beta2, a homologue of cap Z. High concentrations of PIP2 totally prevented the capping of exogenous spectrin-F-actin seeds by dilute supernatants of neutrophil extracts. Capping could also be inhibited, albeit less effectively, by PIP and PI, but not by other phospholipids. When incubated with filaments in the absence of supernatant, PIP2 increased the number of growing ends. PIP2 also uncapped previously capped actin filaments, as demonstrated by incubating supernatant-capped and uncapped seeds with and without PIP2 and then comparing the initial elongation rates after addition of pyrenyl-G-actin. Incubation of capped seeds with high concentrations of PIP2 increased the number of free barbed ends to a level comparable to that of the uncapped seeds exposed to PIP2. PIP2 caused uncapping to occur too quickly to be explained simply by the off-rate of capping protein-beta2, implying that PIP2 interacted directly with capping protein on the filament ends. In fact, PIP2 transiently uncapped capped seeds in the presence of excess free capping protein. From our data, we estimate that millimolar concentrations of PIP2 (almost 100-fold higher than the amount predicted from the effective concentration in purified systems) would be required to inhibit all the capping protein-beta2 in the cytosol. This discrepancy probably results, in large part, from sequestration of PIP2 by other PIP2-binding proteins in the cytoplasm. If PIP2 mediates differential cytoskeletal growth after chemoattractant stimulation in vivo, very high concentrations may be required subjacent to the plasma membrane for regional severing and uncapping of actin filaments to occur quickly near the perturbed membrane. PMID- 9366259 TI - Effects of extracellular Mg2+ concentration on intracellular signalling and acid secretion in rat gastric parietal cells. AB - In the present study, the effects of extracellular magnesium concentration ([Mg2+]ex) on stimulus-secretion coupling processes were investigated in rat gastric parietal cells in vitro. Extracellular magnesium reduction resulted in (1) an increase of basal intracellular free calcium concentration ([Ca2+]in), (2) an enhancement of both carbachol and thapsigargin-induced calcium responses, (3) an improved filling state of intracellular calcium stores, (4) an increase of both basal and carbachol-induced acid secretion, whereas intracellular adenosine 3',5'-cyclic monophosphate (cyclicAMP) levels and histamine stimulated acid secretion were not affected. The effects of high [Mg2+]ex were opposite to the described results, except that high [Mg2+]ex was able to decrease significantly histamine-stimulated cyclicAMP levels and acid secretion. These findings indicate a modulatory role of [Mg2+]ex on the intracellular signalling processes and acid secretory properties in rat parietal cells. These effects seemed to be mediated by regulating (1) calcium loading capacity of intracellular stores, (2) the permeability of the calcium influx pathway, and (3) the formation of cyclicAMP. PMID- 9366260 TI - EGF receptor phosphorylation is affected by ionizing radiation. AB - Eukaryotic cells respond to ionizing radiation with cell cycle arrest, activation of DNA repair mechanisms, and lethality. However, little is known about the molecular mechanisms that constitute these responses. Here we report that ionizing radiation enhances epidermal growth factor (EGF) receptor tyrosine phosphorylation in intact cells as well as in isolated membranes of A431 cells. Phosphoamino acid analysis revealed that ionizing radiation preferentially enhances tyrosine phosphorylation, while EGF enhances the phosphorylation of all three phosphoamino acids (serine, threonine and tyrosine) of the EGF receptor. In addition, radiation reduces the turnover rate of the EGF receptor, while EGF increases the rate of the receptor turnover and down-regulation. Moreover, the confined radiation-induced phosphorylation of tyrosine residues is inhibited by genistein, indicating that this phosphorylation of EGF receptor is due to protein tyrosine kinase activation. These studies provide novel insights into the capacity of radiation to modulate EGF receptor phosphorylation and function. The radiation-induced elevation in the EGF receptor tyrosine phosphorylation and the receptor's slower rate of turnover are discussed in terms of their possible role in cell growth and apoptosis modulation. PMID- 9366261 TI - Vanadate stimulation of 2-deoxyglucose transport is not mediated by PI 3-kinase in human skeletal muscle. AB - Glucose transport in mammalian skeletal muscle is stimulated by insulin, hypoxia and tyrosine protein phosphatase inhibitors such as vanadate. However, it is unknown whether the vanadate signaling mechanism shares a common or separate pathway with insulin or hypoxia. Therefore, experiments were conducted on incubated human muscle strips to compare the effects of vanadate with insulin and hypoxia stimulated 2-deoxyglucose transport (2-DOG). We also used the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor wortmannin to examine whether PI 3-kinase is a common step by which each stimulate glucose transport. Results demonstrate that whereas the effects of vanadate and hypoxia were additive with insulin stimulated glucose transport, the effect of vanadate plus hypoxia was not. In addition, wortmannin significantly (P < 0.05) reduced insulin but not vanadate or hypoxia stimulated 2-DOG transport. Moreover, PI 3-kinase activity was significantly elevated (P < 0.05) in the presence of insulin but not vanadate. In conclusion, these data suggest that vanadate and hypoxia stimulate glucose transport via a similar signaling pathway which is distinct from insulin and that the vanadate signaling pathway is not mediated by PI 3-kinase in human skeletal muscle. PMID- 9366262 TI - Adenylyl cyclase type II is stimulated by PKC via C-terminal phosphorylation. AB - Adenylyl cyclases of the type II family differ from other subforms in that they are conditionally stimulated via alpha(s)/betagamma subunits and regulated by PKC mediated phosphorylation. AC II, stably expressed in HEK 239 cells, was incubated with the PKC activator tetradecanoylphorbol acetate (TPA). Using cells metabolically labeled with [32P]phosphate, TPA caused concerted stimulation of basal and forskolin activated adenylyl cyclase together with incorporation of [32P]phosphate into AC II protein. Enhanced phosphorylation was also indicated by a monoclonal anti-phosphothreonine antibody. Assignment of TPA-induced [32P]phosphate-incorporation to specific sites was achieved by a combination of chemical and immunochemical methods. Three out of five [32P]labeled peptides that were generated by fragmentation with N-chlorosuccinimide were also recognized by the monoclonal antibody BBC-4 [S. Mollner, T. Pfeuffer, Eur. J. Biochem. 171 (1988) 265-271] directed against an epitope 8 kDa from the extreme C-terminus. These findings suggested Ser-871 (consensus sequence ARSLK) and Thr-1057 (CTCR) as acceptor candidates of phorbolester induced phosphoryl transfer. PMID- 9366263 TI - Type of inducing signal regulates transactivation by p53. AB - The tumor suppressor gene p53 is expressed in the contrasting cell fates apoptosis and proliferation. We examined whether the transactivation of the p53 target genes, waf1 and mdm2, is dependent on the cause of p53 induction in human peripheral blood mononuclear cells (PBMC). Both apoptosis triggered by the purine analog 2-chlorodeoxyadenosine (CdA) and growth stimulation by the mitogen phytohemagglutinin (PHA) induced a comparable level and time course of p53 mRNA expression. Both stimuli led also to an increase of p53 protein levels. The cytotoxic agent, but not the mitogen, led to transactivation of waf1 and mdm2 within 18 h. Transactivation was followed by apoptosis of 89% of the PBMC within 48 h. The c-myc oncogene and poly(ADP-ribose)polymerase (PARP), which also have a dual function in proliferation and apoptosis, showed an early induction by both CdA and PHA. These results add further evidence that growth stimulation and DNA damage-induced apoptosis share early gene activation pathways in normal cells. However, since p53 does selectively translate into transactivation of target genes depending on the cause of induction, this function of p53 seems to be regulated by additional factors, which are closely related to the ultimate fate of the cell. PMID- 9366264 TI - Paramagnetic NMR shifts in cyanoferricytochrome c. Investigation of thermal stability and deviations from Curie law behaviour. AB - The paramagnetic shifts of 13C nuclei positioned alpha to the haem in cyanoferricytochrome c are reported and analysed in terms of molecular orbitals based on D4h symmetry with a rhombic perturbation. The temperature dependence of the Fermi contact and dipolar shifts of the haem and axial histidine ligand show deviations from Curie Law behaviour which are explained by a Boltzmann distribution between partially filled 3e(pi) molecular orbitals and the ground and first excited state Kramers doublets. The comprehensive explanation of the temperature dependence of the paramagnetic shifts leads to the conclusion that there is no detectable temperature dependence of the haem orientation or that of the His ligand orientation. This work also provides evidence for the role of the axial His ligand in determining the orientation of the magnetic z-axis. PMID- 9366265 TI - Elucidation of the disulfide-bonding pattern in the factor I modules of the sixth component (C6) of human complement. AB - Complement component C6 is known to contain two factor I modules in tandem at its C-terminus. To localize the disulfide bridges in those domains, native C6 was cleaved with trypsin, followed by subtilisin. The resulting digests were separated by reversed-phase HPLC, and all of the potential cystine-containing fragments were detected by a fluorescence assay and amino acid composition analyses. Final identification of the disulfide bonds was achieved by Edman degradation of the corresponding peptides. From the data gained a 1-3, 2-9, 4-7, 5-10, 6-8 pattern was determined (Cys752-Cys802, Cys763-Cys780, Cys765-Cys816, Cys772-Cys795, Cys841-Cys852, Cys846-Cys898, Cys859-Cys876, Cys861-Cys911, Cys867 Cys891). These findings are compared with the strongly related complement components C7 and factor I. PMID- 9366266 TI - The effect of the metal ion on the folding energetics of azurin: a comparison of the native, zinc and apoprotein. AB - The unfolding by guanidine hydrochloride (GuHCl) and the refolding on dilution of zinc and apoazurin have been monitored by far-UV circular dichroism (CD). With the native protein, the unfolding was followed by CD and optical absorption in the visible spectral region. With the zinc protein, the reversible unfolding has also been followed by tryptophan fluorescence and NMR. The zinc and Cu2+ metal ions remain associated with the protein in the unfolded state. When the unfolding of the native protein is followed by CD, the initial, reversible transition due to unfolding is followed by a slow change associated with the reduction of Cu2+ by the thiol group of the ligand Cys112. The unfolding of apoazurin displays two CD transitions, which evidence suggests represent different folding domains, the least stable one including the metal-binding site and the other one the rest of the beta-sheet structure. Both occur at a lower GuHCl concentration than the unfolding of the native protein. The CD titrations also demonstrate that zinc azurin has a lower stability than the copper protein. Unfolding of zinc azurin followed by tryptophan fluorescence occurs at a much lower GuHCl concentration than the CD changes, and NMR spectra show that there is no loss of secondary and tertiary structure at this concentration, whereas the CD-detected loss of secondary structure correlates with the NMR changes. Thus, the fluorescence change is ascribed to a small local perturbation of the structure around the single tryptophan residue. The differences in stability of the three forms of azurin are discussed in terms of the rack mechanism. A bound metal ion stabilizes the native fold, and this stabilization is larger for Cu(II) than for Zn(II), reflecting the higher affinity of the protein for Cu(II). PMID- 9366267 TI - Partial reconstitution of mammalian phosphoribosylpyrophosphate synthetase in Escherichia coli cells. Coexpression of catalytic subunits with the 39-kDa associated protein leads to formation of soluble multimeric complexes of various compositions. AB - Rat liver phosphoribosylpyrophosphate (PRPP) synthetase exists as complex aggregates composed of 34-kDa catalytic subunits (PRS I and PRS II) and homologous 39- and 41-kDa proteins termed PRPP synthetase-associated proteins (PAPs). While a negative regulatory role was indicated for PAPs, the physiological function of PAPs is less well understood. We attempted to prepare recombinant 39-kDa PAP (PAP39) and to reconstitute the enzyme complex. Free PAP39 was poorly expressed in Escherichia coli, while expression of protein fused with glutathione S-transferase was successful. The purified fusion protein had no PRPP synthetase activity, and bound to dissociated PRS I and PRS II, with a similar affinity. A free form of PAP39 prepared from the fusion protein formed insoluble aggregates. The enzyme complex was then partially reconstituted in situ by coexpression of PAP39 with PRS I or PRS II in E. coli cells. This coexpression led to formation of soluble complexes of various compositions, depending on the conditions. When the relative amount of PAP39 was higher, specific catalytic activities, in terms of the amount of the catalytic subunit, were lowered. PAP39 complexed with PRS I was more readily degraded by proteolysis than seen with PRS II, in vivo and in vitro. These results provide additional, strong evidence for that PAP39 has no catalytic activity in the enzyme complex, but does exert inhibitory effects in an amount-dependent manner, and that composition of the enzyme complex varies, depending on the relative abundance of components present at the site of aggregate formation. PMID- 9366268 TI - A comparative study of the thermal inactivation of cytosolic and mitochondrial aspartate aminotransferases. AB - Rates of irreversible thermal inactivation of cytosolic and mitochondrial aspartate aminotransferases were measured over a large temperature range. Inactivation occurred by different kinetic pathways at high and low temperature with a transition point at about 60 degrees C. This suggests that the isoenzymes exist in different conformations above and below that temperature. Discontinuities in plots of ln(Vmax) against 1/T provided confirmatory evidence for this hypothesis. Activation parameters (deltaH and deltaS) for the thermal inactivation process were calculated in the high and low temperature ranges. At high temperature the greater rate of inactivation of the mitochondrial isoenzyme is determined largely by a high value of deltaS. This more than compensates for the fact that the deltaH is also greater for the mitochondrial isoenzyme indicative of greater intramolecular stabilising interactions compared with the cytosolic form. Thus the relative rates of inactivation are determined by the nature of the transition states rather than by intramolecular interactions in the folded proteins. At lower temperatures the kinetic stabilities of the isoenzymes reverse with the mitochondrial isoenzyme inactivating more slowly. This is largely because of a considerably smaller deltaS at low temperature which no longer compensates for the greater deltaH compared with the cytosolic isoenzyme. PMID- 9366269 TI - On the role of the acidic cluster Glu 92-94 of spinach ferredoxin I. AB - The role of the acidic cluster Glu 92-94 of spinach ferredoxin I in the interaction both with the photosystem I multisubunit complex and the ferredoxin NADP+ reductase, either membrane-bound or purified, was studied by kinetic characterization of site-directed mutants. Three mutants of ferredoxin have been produced to evaluate the effects of elimination of one or two negative charges in the three specific positions of the acidic cluster. Kinetic characterization of the ferredoxin mutants E92A/E93A, E93A and E93A/E94A as electron carriers in the photosynthetic electron transport chain, allowed to establish that the two latter mutants were nearly indistinguishable from the wild-type protein in their ability to be photoreduced by photosystem I and as electron donor to the reductase in the NADP+ photoreduction with thylakoid membranes. The E92A/E93A ferredoxin mutant behaved very similarly to E92 mutants previously characterized. Thus, the elimination of the carboxyl groups adjacent to residue 92 did not further impaired ferredoxin I main function, i.e., as an electron carrier in NADP+ photoreduction. The two double mutants showed a reduced rate in the cross-linking of ferredoxin to the reductase promoted by a soluble carbodiimide, indicating an involvement of the acidic cluster in the formation of the active covalent complex between the two proteins. PMID- 9366270 TI - Purification and characterization of a novel Kazal-type serine proteinase inhibitor of neutrophil elastase from sheep lung. AB - A Kazal-type elastase inhibitor was purified by trichloroacetic acid precipitation of sheep lung lavage fluid followed by chymotrypsin affinity and gel-filtration chromatography of the supernatant. Sheep lung elastase inhibitor (SLEI) is glycosylated. Laser desorption mass spectrometry indicated that SLEI has a molecular mass of 16.8-17.3 kDa. Partial protein sequence of SLEI and of a peptide derived from SLEI showed 31-52% and 51-66% homology at the N-terminus and at the inhibitory site respectively with Kazal-type double-headed proteinase inhibitors (bikazins). SLEI inhibited human leukocyte elastase and porcine pancreatic elastase but not human cathepsin G. It was inactivated by chloramine-T and reactivated when incubated with methionine sulfoxide peptide reductase and dithiothreitol, indicating the presence of a methionine at the active site. The concentration of SLEI in bronchoalveolar lavage fluid (BALF) and lung lymph was 0.28 microM (0.23-0.49); 0.24 microM (0.20-0.31) (median, (range), n = 5), respectively and was undetectable in plasma (< 0.03 microM) suggesting that SLEI is produced in the lung. The median molar ratios of SLEI to alpha1-proteinase inhibitor in BALF and lung lymph were 3.2 to 1 and 0.017 to 1, respectively. These results indicate that SLEI probably makes an important contribution to antielastase defence in epithelial lining liquid. PMID- 9366271 TI - Purification and characterization of a novel poly(U), poly(C) ribonuclease from Saccharomyces cerevisiae. AB - A new ribonuclease from Saccharomyces cerevisiae, specific for poly(U) and poly(C) substrate, was purified near to homogeneity by successive fractionation with DEAE-Sepharose, Heparin-Sepharose and CM-Sepharose chromatography. The purified molecule detected by SDS/polyacrylimide gel electrophoresis has a molecular mass of 29 kDa. The optimum pH for the enzyme activity is 5.5-7 and its isoelectric point is 7.5. The purified enzyme was able to degrade 26S, 18S and 5S rRNAs as well as mRNA obtained from in vitro transcription. No catalytic activity was observed when the RNase was incubated with tRNA and double stranded substrate. Our findings suggest that this novel RNase may play an important role in the processing of RNA in Saccharomyces cerevisiae. PMID- 9366273 TI - N-dibenzylphospho-N'-3-(2,6-dichlorophenyl)propyl-guanidine is a bisubstrate analog for creatine kinase. AB - We describe a new compound, N-dibenzylphospho-N'-3-(2,6-dichlorophenyl) propylguanidine (DPPG), and our study of its interaction with cytosolic CK. To our knowledge, it is the most potent inhibitor known for CK: the Ki value versus ADP was 330 nM and 110 nM for CK-MM and BB respectively. In view of the inhibition pattern, Ki(app) dependencies on the second substrate, and very low Ki values, we conclude that DPPG binds to the active site as a bisubstrate-type analog. This bisubstrate analog confirms different mechanisms for CK-MM and BB: in spite of a more than 80% similarity in amino-acid sequences, both isoenzymes are random at pH 8.6 but CK-BB has an ordered mechanism at pH 6.6. PMID- 9366272 TI - A circular dichroism study of preferential hydration and alcohol effects on a denatured protein, pig calpastatin domain I. AB - Pig calpastatin domain I (CSD1), a proteinase inhibitor that specifically blocks activity of calpain I and II, is a good candidate protein for studying conformational variations in the denatured form of protein. An extensive structural characterization of CSD1 reported in the first part of this work has shown that CSD1 at neutral pH is in an expanded and flexible conformation without secondary and tertiary structures. Next, we further studied cosolvent effects of protein-stabilizers, polyols and sulfate salts, as well as protein-destabilizers, alcohols, on the conformation of CSD1 monitored by far- and near-UV CD spectroscopy. We found that both groups of cosolvents at high concentration induce highly helical structures of CSD1, but without specific tertiary interactions. Based on the results on the polyols and the sulfate salts, we have suggested that the preferential hydration is one of the thermodynamic forces to induce secondary structures in the denatured state of protein. Variations in isodichroic points of changes in far-UV CD spectrum as functions of cosolvent species and their concentration have exhibited complexity of the processes. The present study implies that protein stability in the presence of cosolvents is often determined by free energy difference between the folded and the highly structured denatured state, not between the folded and the random state. PMID- 9366274 TI - The potential role of glycine-160 of human O6-alkylguanine-DNA alkyltransferase in reaction with O6-benzylguanine as determined by site-directed mutagenesis and molecular modelling comparisons. AB - O6-Alkylguanine DNA-alkyltransferase (ATase) repairs toxic, mutagenic and carcinogenic O6-alkylguanine (O6-alkG) lesions in DNA by a highly conserved reaction involving the stoichiometric transfer of the alkyl group to the active centre cysteine residue of the ATase protein. In the Escherichia coli Ada ATase, which is effectively refactory to inhibition by O6-benzylguanine (O6-BzG), the residue corresponding to glycine-160 (G160) for the mammalian proteins of this class is replaced by a tryptophan (W). Therefore, to investigate the potential role of the G160 of the human ATase (hAT) protein in determining sensitivity to O6-BzG, site-directed mutagenesis was used to produce a mutant protein (hATG160W) substituted at position 160 with a W residue. The hATG160W mutant was found to be stably expressed and was 3- and 5-fold more sensitive than hAT to inactivation by O6-BzG, in the absence and presence of additional calf-thymus DNA respectively. A similar, DNA dependent increased sensitivity of the hATG160W mutant relative to wild-type was also found for O6-methylguanine mediated inactivation. The potential role of the W160 residue in stabilising the binding of the O6-alkG to the protein is discussed in terms of a homology model of the structure of hAT. The region occupied by G/W-160 forms the site of a putative hinge that could be important in the conformational change that is likely to occur on DNA binding. Three sequence motifs have been identified in this region which may influence O6 BzG access to the active site; YSGG or YSGGG in mammals (YAGG in E. coli Ogt, YAGS in Dat from Bacillus subtilis), YRWG in E. coli Ada and Salmonella typhimurium (but YKWS in Saccharomyces cerevisiae) or YRGGF in AdaB from B. Subtilis. Finally,conformational and stereoelectronic analysis of the putative transition states for the alkyl transfer from a series of inactivators of hAT, including O6-BzG was undertaken to rationalise the unexpected weak inhibition shown by the alpha-pi-unsaturated electrophiles. PMID- 9366275 TI - Taurocholate-induced dimerization of bovine cholesterol esterase in sodium dodecylsulfate. AB - Purified bovine cholesterol esterase (CE) showed one major band with an apparent molecular mass of 58 kDa on sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In the presence of taurocholate another major band with an apparent molecular mass of 116 kDa, corresponding to the dimer, appeared. Longer heating times and higher concentrations of CE in SDS-sample buffer increased the relative amount of the dimer. Higher SDS concentration in the sample buffer reduced the amount of dimer. Mercaptoethanol concentration had no effect. The dimer did not contain taurocholate and readily reverted to the monomer. It is concluded that taurocholate mediates the dimerization of CE in SDS by facilitating the formation of hydrophobic interactions between monomeric subunits. PMID- 9366276 TI - Introduction: an easy approach to cardiovascular protection. PMID- 9366278 TI - An effective approach for treating elderly patients with isolated systolic hypertension: results of an Italian multicenter study with fosinopril. AB - Cardiovascular diseases are the most common causes of mortality, and hypertension is the most common cardiovascular disease in all ages. The Systolic Hypertension in the Elderly Program (SHEP) trial has shown that the pharmacologic reduction of isolated systolic hypertension can significantly reduce the incidence of cardiovascular complications. The aim of the Italian multicenter study reported here is to compare the efficacy, safety, and tolerability of fosinopril, a novel angiotensin converting enzyme (ACE) inhibitor with a dual route of excretion, with chlorthalidone, the diuretic administered in the SHEP study, in 312 elderly patients with isolated systolic hypertension. Our results show that fosinopril and chlorthalidone produce identical and statistically significant reductions in systolic blood pressure (-23.9 +/- 11.6 mm Hg and -23.7 +/- 10.9 mm Hg, respectively) and, to a lesser extent, in diastolic blood pressure (-7.1 +/- 3.1 mm Hg and -5.2 +/- 2.3 mm Hg, respectively). Only chlorthalidone caused a statistically significant change in uric acid, total cholesterol, blood urea, and serum potassium concentrations. Fosinopril was also somewhat better tolerated than chlorthalidone. In conclusion, the novel ACE inhibitor fosinopril is an effective and well-tolerated antihypertensive agent for use in elderly patients with isolated systolic hypertension and appears to be a suitable alternative for the treatment of isolated systolic hypertension. PMID- 9366277 TI - The hypertensive patient with multiple risk factors: is treatment really so difficult? AB - Multiple risk factors for cardiovascular disease, particularly hypercholesterolemia, are often present in the hypertensive patient. Recent guidelines, ranging from those prepared by the World Health Organization/International Society of Hypertension to those of the three European Societies of Cardiology, Atherosclerosis, and Hypertension, stress the importance of evaluating global risk, based on the presence of all cardiovascular risk factors in an individual or in a group of subjects. It has also been suggested that treatment should aim to correct all modifiable risk factors. This is a reasonable recommendation, but although observational epidemiologic studies have shown that the effects of concomitant risk factors are additive, if not multiplicative, it is surprising that no intervention trial has been undertaken to determine whether the benefits of treating more than one risk factor are also additive. The Plaque Hypertension Lipid-Lowering Italian Study (PHYLLIS) is the first such study. Its aim is to investigate the potential benefit of lowering blood pressure and plasma cholesterol on the progression of carotid plaque in hypertensive patients with elevated plasma cholesterol. Using a factorial design, the antiatherosclerotic effect of two different antihypertensive drugs, the angiotensin-converting enzyme (ACE) inhibitor fosinopril and the diuretic hydrochlorothiazide will be compared. The study aims to confirm animal experiments demonstrating the benefit of ACE inhibitors on experimental atherosclerosis. PHYLLIS will also compare the effects of two lipid-lowering regimens, diet plus placebo and diet plus pravastatin, in the study population. This 3-year, multicenter, double-blind, randomized Italian study, using B-mode ultrasound evaluation of the carotid walls with central reading of the ultrasound scans (Bowman Gray University, Winston-Salem, NC) is now underway and should provide useful evidence about the benefits of multiple risk factor treatment in the hypertensive patient. PMID- 9366279 TI - Treatment of heart failure with fosinopril: an angiotensin converting enzyme inhibitor with a dual and compensatory route of excretion. AB - Congestive heart failure (CHF) is one of the most common and clinically important cardiovascular diseases. This pathologic state is characterized not only by well defined hemodynamic alterations, but also by complex abnormalities involving the sympathetic nervous system, the renin-angiotensin system, and other hormones involved in cardiovascular homeostasis. In addition, there is an abnormality in the homeostatic cardiovascular control exerted by arterial baroreceptors and the viscoelastic properties of medium-size arteries are altered, causing a reduction in arterial compliance. All of these abnormalities can be favorably affected by angiotensin converting enzyme (ACE) inhibitors, which have been shown to improve not only the hemodynamic and neurohumoral profiles of CHF, but also patient survival. CHF is accompanied with a decline or some sort of effect on renal function. An ACE inhibitor with a dual route of excretion, such as fosinopril, may be especially useful in treating patients with CHF. PMID- 9366280 TI - How should we treat hypertensive women with cardiac and renal impairment? AB - Arterial hypertension is the most common chronic medical condition requiring office visits to physicians and is a major contributing factor to the development of myocardial infarction and stroke. Its importance as a cardiovascular risk factor is at least as significant in women as in men; however, the ever-growing literature on hypertension shows surprisingly little data concerning sex differences. Large clinical trials of antihypertensive treatment have not clearly demonstrated gender differences in blood pressure response and outcome, but the majority of patients in these trials were men. Even so, some evidence indicates that white women treated for hypertension obtain less benefit than men. The pathophysiology of hypertension in men and women is similar in many aspects, but important gender differences are now emerging. Studies designed to clarify these differences are required, as a better knowledge of the underlying mechanisms will allow for a more precise stratification of risk and a more accurate approach to both nonpharmacologic and pharmacologic treatment. PMID- 9366281 TI - Post acute myocardial infarction: the Fosinopril in Acute Myocardial Infarction Study (FAMIS). AB - Many studies have clearly documented the beneficial effects of angiotensin converting enzyme (ACE) inhibitors in patients with acute myocardial infarction (AMI). The Fosinopril in Acute Myocardial Infarction Study (FAMIS) was a 2-year randomized, double-blind, placebo-controlled multicenter study investigating the hemodynamic and clinical effects of early (< 9 h from onset of symptoms) administration of fosinopril in 285 patients with anterior AMI undergoing thrombolysis within 6 h of symptom onset. The objective of the study was twofold: 1) to estimate changes in left ventricular (LV) volumes and function over 3 months by a series of echocardiographic evaluations, and 2) to clinically assess mortality and the occurrence of congestive heart failure (CHF) over 2 years. LV volumes measured at baseline (24 to 48 h from symptom onset) were within the normal range in over two-thirds of randomized patients, and the changes in volume were comparable after 3 months of treatment with either fosinopril or placebo. However, fosinopril-treated patients showed a 30% reduction in the 2-year incidence of death or moderate-to-severe CHF (P = .04) despite having a worst prognostic profile at baseline. This benefit of fosinopril was confirmed in the subgroup of patients without CHF on admission, who showed a 34.1% reduction in the 2-year occurrence of CHF (P = .05) and a 29.1% reduction in death or CHF (P = .04). The results of the FAMIS study suggest that early treatment with fosinopril, in conjunction with thrombolysis, can significantly delay the development of CHF in patients with AMI, acting through mechanisms independent of fosinopril's impact on LV remodeling. PMID- 9366282 TI - Treatment of senile hypertension: the Fosinopril in Old Patients Study (FOPS). AB - Data regarding the tolerance of ACE inhibitors in old age are sparse, despite this class of compound being regarded as one of the first-line agents for the treatment of hypertension. In the present trial, the efficacy and tolerance of the ACE inhibitor fosinopril was examined over a period of 12 weeks in an open trial of hypertensive patients aged over 60 years with diastolic hypertension (diastolic blood pressure 95 to 110 mm Hg) and isolated systolic hypertension (ISH; systolic blood pressure 160 to 219 mm Hg, diastolic blood pressure 80 to 94 mm Hg). Fosinopril decreased blood pressure from 174/101 mm Hg to 149/88 mm Hg in patients with diastolic hypertension and from 182/86 mm Hg to 151/80 mm Hg in patients with ISH. Seventy percent of patients did not require any adaptation of the initial fosinopril dose to achieve an adequate therapeutic response. In the patients in whom 20 mg fosinopril did not adequately reduce blood pressure, the addition of 12.5 mg hydrochlorothiazide was found to be slightly more effective than doubling the initial dose of the ACE inhibitor. Fosinopril was well tolerated and the occurrence of drug-dependent side effects was not increased in patients with renal insufficiency. Fosinopril is an excellent therapy for the treatment of hypertension in elderly patients, particularly because, as a consequence of its dual, compensatory excretion, no adaptation of the dose is necessary, even in patients with a physiological reduction in renal function. PMID- 9366283 TI - Management of hypertension: the role of combination therapy. AB - The complementary action of angiotensin converting enzyme inhibitors and diuretics in the treatment of hypertension has been demonstrated in a number of studies of fosinopril and hydrochlorothiazide (HCTZ). The combination provides a clinically significant reduction in blood pressure while minimizing the dose dependent adverse effects of HCTZ, such as hypotension and its metabolic effects on plasma lipoproteins, by keeping the dose of each agent to the minimum. Fosinopril has a unique dual mechanism of elimination and can therefore be used in patients with renal impairment. The efficacy of the combination of fosinopril and hydrochlorothiazide compared with placebo and other agents is reviewed in this article. Studies have demonstrated that the combination is effective in the elderly and in renally impaired patients, regardless of severity. In addition, in non-insulin dependent diabetes, antihypertensive effect is achieved without further affecting carbohydrate and lipid metabolism, which is often the case when thiazide diuretics alone are used. A matrix study was performed to evaluate the optimum dose combination to produce blood pressure normalization and minimize side effects. This study evaluated 17 different dose combinations and demonstrated that the lowest dose combination to produce a clinically significant effect was fosinopril 10 mg and HCTZ 12.5 mg. However, a dose-related antihypertensive effect can be seen, giving the option for the use of 20 mg fosinopril for moderately hypertensive patients. Both combination therapy and fosinopril were significantly more effective than HCTZ alone or placebo. The fosinopril/HCTZ combination has also been shown to have a comparable effect to sustained-release nifedipine and propanolol + HCTZ. The studies reviewed here demonstrate that fosinopril/HCTZ combination treatment has a number of advantages over either agent used alone, providing blood pressure normalization in a broad range of hypertensive patients, including diabetic patients and the elderly. PMID- 9366284 TI - Pharmacoeconomics of angiotensin converting enzyme inhibitors in heart failure. AB - As a result of the increasing cost of health care and the limited resources available, it has become more difficult to allocate resources efficiently and effectively in the health care system. This environment has led to the development of pharmacoeconomic studies, which have been designed in response to the need for assessment of the economic benefits of a product prior to its acceptance in the market. The field of pharmacoeconomics has grown rapidly, especially in relation to the development of new pharmacological products. Economic analysis is now routinely incorporated into many clinical trials, and this type of information, in conjunction with the usual safety and efficacy data, is becoming more important to pharmaceutical companies, regulatory authorities, third party payers, and end-users. The cost-effectiveness of angiotensin converting enzyme (ACE) inhibitors for the treatment of heart failure has been evaluated on the basis of a number of large-scale studies, including the Survival and Ventricular Enlargement (SAVE) study and the Veterans Administration Cooperative Vasodilator Heart Failure Trials (V-HeFT I and II). The cost effectiveness of the ACE inhibitor captopril compares favorably with other cardiac interventions, reducing both mortality and the incidence of congestive heart failure (CHF). Captopril also appears to be cost-effective in the treatment of patients with left ventricular dysfunction after acute myocardial infarction. In addition, analysis of more recent studies of the treatment of fosinopril in patients with mild to moderate CHF have been performed and have proved this newer ACE inhibitor to be cost-saving in these patients. PMID- 9366285 TI - The progression from hypertension to heart failure. AB - Heart failure (HF) still presents a major health problem despite significant understanding of its underlying pathophysiology and recent therapeutic advances. Hypertension is a major risk factor for HF and plays a key role in the evolution of the disease. In an attempt to compensate for the increased peripheral resistance frequently noted in hypertension, the heart may hypertrophy, with the left ventricular enlargement accompanied by fibrosis and resulting in reduced contractility. Ultimately the hypertrophied or fibrosed myocardium is no longer able to maintain normal cardiac output and left ventricular failure occurs. Evidence shows that treating hypertension effectively can have a major beneficial impact on some, but not all, forms of adult cardiovascular disease. For example, the incidence of HF and stroke are clearly reduced; however, until recently, treating hypertension has had relatively little effect on coronary heart disease (CHD) events. The benefits of antihypertensive treatment are, however, clearly underestimated, possibly because many studies are too short and because more subtle benefits of treatment have been overlooked. Also, it must be realized that hypertension is a complex disorder and antihypertensive drugs do indeed differ regarding their effects on associated metabolic derangements often seen in hypertensive patients. Angiotensin converting enzyme (ACE) inhibitors have been shown to be highly efficacious and safe antihypertensive agents, and have additional favorable effects on metabolic parameters, renal functions, and cardiac hypertrophy. ACE inhibitors are now the mainstay of therapy in the patients with heart failure and it is now well recognized that earlier and more aggressive treatment of hypertension may reduce the incidence of HF. ACE inhibitors are an excellent choice as an antihypertensive agent; however, many physicians limit their use of ACE inhibitors due to concern about possible renal side-effects, which accompanied the early use of these agents at very high doses. PMID- 9366286 TI - Treatment of congestive heart failure: experience with fosinopril. AB - The prevalence of congestive heart failure (CHF), a debilitating condition associated with impaired quality of life and markedly shortened life expectancy, is increasing. The goals of therapy for CHF are reducing symptoms, improving functional capacity, and slowing the progression of the condition. In most cases, this is best achieved with a combination of diuretic and vasodilator therapy. Angiotensin-converting enzyme (ACE) inhibitors have several advantages over other vasodilatory agents and are becoming widely used for treating CHF. The most recently introduced ACE inhibitor, fosinopril, is at least as effective as enalapril, and its dual and compensatory route of excretion is particularly advantageous in patients with renal insufficiency. Fosinopril may also have particular benefits in the prevention of CHF, as it has beneficial effects on cardiac function that may help delay the onset of overt cardiac failure. PMID- 9366287 TI - Cancer and the functional status of the elderly. PMID- 9366288 TI - Pesticides and cancer risk. PMID- 9366289 TI - Alterations of p16INK4A and p15INK4B genes in gastric carcinomas. AB - BACKGROUND: It has been suggested that cyclin-dependent kinase inhibitors (CDKIs), including p16 and p15, are tumor suppressor genes. Alterations of CDKIs have been found in most types of cancer. However, little is known about the status of p16 and p15 genes, including methylation of the promoter region, in gastric carcinoma. METHODS: Thirty-six primary gastric tumors and 9 gastric carcinoma cell lines were examined for alterations of the p16 and p15 genes. Deletion of the p16 and p15 genes was assessed by Southern blot analysis, expression by Northern blot analysis, and mutation by polymerase chain reaction single strand conformation polymorphism followed by direct sequencing. The methylation status of the 5' CpG island of the p16 gene was evaluated using methylation-sensitive restriction enzymes, and reversal of the transcriptional block of the p16 gene was determined by Northern blot analysis after treatment with 5-aza-2'-deoxycytidine. RESULTS: Homozygous deletions of the p16 and 15 genes from 2 of 9 gastric carcinoma cell lines were found. In contrast, no deletions were detected in 36 primary gastric tumors, and one primary tumor showed rearrangements of the p16 and p15 genes. Two gastric carcinoma cell lines showed a point mutation and an insertional mutation of the p16 gene, respectively; however, no point mutations were noted for the p16 and p15 genes in any of the primary gastric tumors. Constitutive levels of p16 mRNA expression in gastric carcinoma cell lines were quite heterogeneous; four gastric carcinoma cell lines had no detectable p16 mRNA and 6 gastric carcinoma cell lines had negligible expression of p15 mRNA. Of 10 primary gastric tumors, only 1 tumor expressed p16 mRNA. Furthermore, abnormal DNA methylation patterns of the p16 gene were found in 2 gastric carcinoma cell lines through the use of methylation sensitive restriction enzymes. These cell lines lacked expression of p16 mRNA without deletions of the p16 gene. These transcriptional blocks were reversed by treatment with 5-aza-2'-deoxycytidine. CONCLUSIONS: Deletions or mutations of the p16 and p15 genes are uncommon in primary gastric carcinomas. However, defective mRNA transcription, sometimes by aberrant DNA methylation, might be one of the pathways of inactivation of the p16 gene that leads to the development of gastric carcinoma. PMID- 9366290 TI - Vitamin C inhibits the growth of a bacterial risk factor for gastric carcinoma: Helicobacter pylori. AB - BACKGROUND: Helicobacter pylori infection is a risk factor for gastric carcinogenesis. High dietary vitamin C intake appears to protect against gastric carcinoma. It has been suggested that vitamin C exerts the protective effect by scavenging free radicals that may be enhanced by H. pylori. However, vitamin C has not been investigated in relation to the direct action on H. pylori. In this study, the authors attempted to clarify this possibility both in vitro and in vivo. METHODS: Susceptibility testing of H. pylori (64 strains) was performed by the agar dilution method. Bactericidal actions were determined by a broth cultivation technique. The effect of vitamin C on in vivo H. pylori colonization was evaluated by using the Mongolian gerbil model. RESULTS: At concentrations of 2048, 512, and 128 microg/mL (minimum inhibitory concentrations [MICs]), vitamin C could inhibit the growth of 90% of the bacterial stains incubated at pH values of 7.4, 6.0, and 5.5, respectively. The broth cultures exposed to the MICs of vitamin C displayed a 1.57 approximately 2.5-log decrease in the number of viable bacteria, and the loss of viability was observed in 24 hours at concentrations 8 fold higher than the MICs. In an in vivo experiment, H. pylori colonies decreased significantly in animals treated with vitamin C after oral administration of vitamin C (10 mg/head/day) for 7 days. CONCLUSIONS: High doses of vitamin C inhibit the growth of H. pylori in vitro as well as in vivo. PMID- 9366291 TI - Combined pancreaticoduodenectomy and hepatectomy for patients with locally advanced gallbladder carcinoma: long term results. AB - BACKGROUND: The objective of this study was to evaluate the efficacy of combined pancreaticoduodenectomy and hepatectomy for the treatment of patients with locally advanced gallbladder carcinoma. METHODS: Long term results over 5 years of follow-up were analyzed retrospectively in 17 consecutive patients with gallbladder carcinoma who underwent combined pancreaticoduodenectomy and hepatectomy with radical lymphadenectomy. The indications for pancreaticoduodenectomy were direct invasion of the adjacent organs (stomach, duodenum, or pancreas) and/or the presence of peripancreatic (head only) lymph node metastases. The hepatectomy performed was a nonanatomic resection of the gallbladder bed in 15 patients and an extended right hepatectomy in 2 patients. There was 1 in-hospital death (6%). RESULTS: Overall, 5 patients (29%) survived 5 years after surgery. Of these patients, four had Stage IVB disease with positive peripancreatic lymph nodes. Eight of the 10 patients who underwent a potentially curative resection survived longer than 3 years, whereas none of the 7 patients with residual tumor survived beyond 15 months. The 5-year survival of 50% (median survival: 58.5 months) in those undergoing a potentially curative resection was significantly better than the 5-year survival of 0% (median survival: 8 months) observed in those patients with residual tumor (P = 0.00086). CONCLUSIONS: Combined pancreaticoduodenectomy and hepatectomy is an efficacious treatment for patients with locally advanced gallbladder carcinoma, but only if a potentially curative resection is feasible. The presence of peripancreatic (head only) lymph node disease is not a contraindication for this procedure. PMID- 9366292 TI - Multicentric endobronchial smooth muscle tumors associated with the Epstein-Barr virus in an adult patient with the acquired immunodeficiency syndrome: a case report. AB - BACKGROUND: The incidence of benign and malignant smooth-muscle tumors (leiomyomas and leiomyosarcomas) is increased in children with the acquired immunodeficiency syndrome (AIDS). Epstein-Barr virus (EBV) infection has been implicated in the pathogenesis of these tumors. Smooth muscle tumors in adults with AIDS are extremely rare, with only six cases involving extrapulmonary sites reported in the literature. METHODS: Multifocal smooth walled endobronchial tumors were removed from a 35-year-old man with AIDS using rigid bronchoscopic laser resection. The tumor tissues were processed for routine histology, immunohistochemical stainings, and EBV in situ hybridization using an EBV-encoded RNA- 1 RNA oligonucleotide probe. RESULTS: Histologic features and immunohistochemical profiles were characteristic of smooth muscle tumors. EBV gene expression was detected in > 90% of tumor cell nuclei. Although overt histopathologic evidence of malignancy was lacking, some of the histopathologic findings, along with multifocality of the tumors and the rapid appearance of new tumors, suggested an unfavorable prognosis in this case. CONCLUSIONS: To the authors' knowledge, this is the first reported case of multicentric smooth muscle tumors involving the bronchi and lungs of an adult patient with AIDS. Diffuse EBV gene expression in the tumor tissue supports the hypothesis that EBV infection contributes to the pathogenesis of tumors of smooth muscle origin in immunocompromised hosts. PMID- 9366293 TI - Fibroblastic colony-forming units and levels of tumor necrosis factor and prostaglandin E2 in bone marrow cultures from patients with advanced lung carcinoma. AB - BACKGROUND: Although alterations of the bone marrow (BM) fibroblast colony forming cells are involved in the development of diverse hematologic disorders, these progenitors still have not been well characterized in patients with solid tumors. METHODS: The incidence of fibroblast colony-forming units (CFU-F) was evaluated in the cultures of unseparated and fractionated light density BM mononuclear cells (MC) from 25 consecutive untreated lung carcinoma patients (LCP) and 16 normal controls (NC). Unseparated MC also were cultured in the presence of indomethacin (10[-6] M). Finally, the authors evaluated the spontaneous production of prostaglandin E2 (PGE2) and tumor necrosis factor-alpha (TNF-alpha) in culture conditioned mediums of unseparated MC by radioimmunoassay and enzyme-linked immunoadsorbent assay methodology, respectively. RESULTS: A decreased number of CFU-F was observed in unseparated and fractionated (adherent and nonadherent) light density MC cultures from LCP compared with NC. When unseparated MC of LCP were treated with indomethacin, a slightly increase in the number of CFU-F was found. Adherent MC (stromal cells) achieved confluence only in 44% of LCP primary cultures compared with 100% of NC. Overproduction of PGE2 and TNF-alpha was found in the conditioned mediums of LCP compared with the mean values obtained in NC (P < 0.05 and P < 0.02, respectively). CONCLUSIONS: The lack of confluence and suppression of CFU-F in BM of LCP may be related to the increase production of PGE2 and TNF-alpha. Future investigation will allow the determination of how these modifications influence tumor cell growth and will prove if more alterations of the hematopoietic microenvironment imply a worse prognosis. PMID- 9366294 TI - The stiffness of lymph nodes containing lung carcinoma metastases: a new diagnostic parameter measured by a tactile sensor. AB - BACKGROUND: It is believed that the stiffness or hardness of a lymph node containing a metastasis differs from that of lymph node without a metastasis because of the difference in tissue density, which is derived from the lymph node's histopathologic features. Prior to this study, however, there had been no attempts to quantify the hardness or stiffness of lymph nodes. The authors developed a new tactile sensor and system for measuring the stiffness (g/cm) of lymph nodes accurately, and they studied its utility as a tool for diagnosing lymph node metastases. METHODS: Clinical specimens were obtained from 14 patients who underwent lobectomy or pneumonectomy with hilar and mediastinal lymph node dissection for nonsmall cell lung carcinoma at the University of Tokyo between January and July 1996. With the tactile sensor developed by the authors, 212 resected lymph nodes were measured for their stiffness. RESULTS: Among these 212 resected lymph nodes, 57 were diagnosed as containing metastases (38 from adenocarcinomas and 19 from squamous cell carcinomas). The mean stiffness of the lymph nodes that contained metastases was 3.35 +/- 1.57 g/cm, and that of lymph nodes without metastases was 1.23 +/- 0.50 g/cm (P < 0.001). Receiver operating characteristic analysis revealed that the area under the curve was 0.93, indicating excellent accuracy of the method. When the cutoff was 1.5 g/cm, the sensitivity was 91.2% and the specificity was 78.1% for detection of lymph node metastases. CONCLUSIONS: Measurement of the stiffness of resected lymph nodes was confirmed as an accurate approach to diagnosing lymph node metastases without knowledge of other factors, such as lymph node size or color. PMID- 9366295 TI - Waldenstrom's macroglobulinemia: a clinicopathologic study of 22 cases. AB - BACKGROUND: Waldenstrom's macroglobulinemia (WM) is a rare immunoproliferative disorder, the clinical course of which varies. In related B-cell neoplasms, such as multiple myeloma and chronic lymphocytic leukemia, the histologic features of bone marrow are considered to be of prognostic relevance. METHODS: To assess the prognostic features of WM, the authors reviewed the clinical and pathologic features of 22 patients. Bone marrow aspirates and core biopsies were available for each case. Immunostains for a panel of hematopoietic markers as well as p53 and proliferating cell nuclear antigen (PCNA) were performed. RESULTS: There were 14 males and 8 females, with a mean age of 60 years. At presentation, two histologic subtypes, lymphoplasmacytoid (73%) and lymphoplasmacytic (27%), were observed. Four patterns of bone marrow infiltration were delineated: diffuse (45%), nodular-interstitial (22%), mixed paratrabecular-nodular (20%), and paratrabecular (13%). In 11 patients, the infiltrate occupied greater than 70% of the bone marrow; in 8 patients, 30-70%; and in 3 patients, less than 30%. PCNA reactivity was observed in 58% of cases and p53 reactivity in 21%. Ten patients died of disease with an average survival of 84 months. The remaining 12 patients were alive with disease at last follow-up. The pretreatment parameters that were correlated with shorter survival were hemoglobin, white blood cell count, platelet count, splenomegaly, lymphadenopathy, and serum immunoglobulin M level. CONCLUSIONS: The findings of this study suggest that some pretreatment parameters, such as cytopenia, serum immunoglobulin M level, splenomegaly, and lymphadenopathy, correlate with poor prognosis for patients with WM. In contrast, histologic features and expression of p53 and PCNA did not correlate significantly with survival. PMID- 9366296 TI - Quality of life for adult leukemia survivors treated on clinical trials of Cancer and Leukemia Group B during the period 1971-1988: predictors for later psychologic distress. AB - BACKGROUND: To identify predictors of psychosocial adjustment for survivors of adult acute leukemia, the adaptation of 206 survivors (77% with acute myelogenous leukemia, and 23% with acute lymphocytic leukemia) treated on any of 13 Cancer and Leukemia Group B trials during the period 1971-1988 was examined. METHODS: Survivors (median age, 41 years) who were at least 1 year from completion of all treatment (median, 5 years) were interviewed by telephone about psychologic symptoms; social, sexual, and vocational function; and beliefs about control over health. Standardized psychologic instruments were used to evaluate survivors' responses. RESULTS: Most survivors adapted well; however, 14% were 1.5 standard deviations above normal on the Global Severity Index of the Brief Symptom Inventory. Predictors of greater psychologic distress included less education, younger age, anticipatory distress during chemotherapy treatment, and the combination of more medical problems after treatment with poorer family function. Anticipatory nausea and distress during chemotherapy predicted persistent visceral distress later, which occurred with reminders of treatment. Anticipatory vomiting predicted a greater tendency toward cancer-related intrusive thoughts and avoidance of reminders. CONCLUSIONS: Patients experiencing anticipatory distress during treatment who are younger and less educated should be monitored for depressive syndromes later. PMID- 9366298 TI - The prevalence of familial testicular cancer: an analysis of two patient populations and a review of the literature. AB - BACKGROUND: Undescended testes and antecedent testicular tumor are recognized risk factors for testicular germ cell cancer. It has been suggested that a family history of testicular cancer constitutes another major risk indicator. This postulation is mainly based on clinical observations and on very few systematic investigations. In the current study, the authors analyzed the proportion of familial testicular cancer in their study population and estimated the relative risk created by a family history of the disease. METHODS: The proportion of familial testicular cancer was analyzed in a prospective multicentric study involving 1692 patients. The median ages of patients with and without a family history of the disease were compared. In a different patient population consisting of 518 patients and 531 age-matched controls, the frequency of family history was investigated and the relative risk calculated. In addition, a literature survey was performed to look for previous systematic reports on familial testicular cancer. RESULTS: In the prospective study, 18 patients (1.1%; 95% confidence interval, 0.63-1.68%) had a first-degree relative afflicted with testicular cancer. Age at presentation was not significantly different between patients with a family history and those without. In the retrospective series, the proportion of those with a family history was 1.7% (95% confidence interval [CI], 0.80-3.27%). There was a 3.1-fold increased relative risk (95% CI, 0.77 17.95) for first-degree relatives of patients with testicular cancer. Ten previous reports on familial testicular cancer were identified in the literature. Combining the results of those previous reports and the current study led to a weighted mean prevalence of familial testicular cancer of 1.35% (95% CI, 1.12 1.58%). CONCLUSIONS: The current study underscores that susceptibility to testicular germ cell cancer is influenced by genetic factors. A family history of testicular cancer is encountered in about 1.35% of patients. The relative risk for first-degree relatives of patients with the disease is increased by a factor of 3-10. PMID- 9366297 TI - Vascular permeability factor (vascular endothelial growth factor) expression and angiogenesis in patients with ductal carcinoma in situ of the breast. AB - BACKGROUND: Prior studies have indicated that ductal carcinoma in situ (DCIS) lesions are capable of inducing a vascular stroma. However, the mechanisms responsible for angiogenesis in DCIS currently are not defined. The goal of this study was to determine the relationship between the expression of the angiogenic cytokine vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), and angiogenesis in patients with DCIS. METHODS: Forty-six breast biopsies with DCIS were characterized with regard to histologic features on hematoxylin and eosin stained sections, and microvessel density and distribution using sections immunostained for factor VIII-related antigen. In addition, in situ hybridization was performed on formalin fixed, paraffin embedded sections using 35S labeled riboprobes specific for VPF/VEGF. RESULTS: VPF/VEGF expression by tumor cells in DCIS was greater than that observed in adjacent benign ductal or lobular epithelial cells in 96% of the evaluable cases. Moreover, the degree of VPF/VEGF mRNA expression was significantly associated with the degree of angiogenesis in these lesions. Among 22 cases with strong VPF/VEGF mRNA expression, the median microvessel count was 100 +/- 30.6 vessels/field. In contrast, among 24 cases with low level VPF/VEGF mRNA expression, the median microvessel count was 71 +/- 48.6 vessels/field (P = 0.04). In addition, high grade DCIS lesions more commonly were associated with strong VPF/VEGF mRNA expression than low grade lesions, but the results were not statistically significant. CONCLUSIONS: These findings suggest that VPF/VEGF is an important angiogenic factor in patients with DCIS. PMID- 9366299 TI - Adult Wilms' tumor: a case report. AB - BACKGROUND: Wilms' tumor in an adult is rare and no treatment guidelines have been established, although all authors recommend aggressive therapy based on surgery, radiotherapy, and multiagent chemotherapy. METHODS: The authors describe a case of Wilms' tumor in a 23-year-old woman who developed hepatic and pulmonary metastases after undergoing nephrectomy. Treatment was initiated with carboplatin, etoposide, ifosfamide, and epirubicin combination chemotherapy and irradiation of the tumor bed, lungs, and liver. RESULTS: Metastatic workup was negative 41 months after suspension of chemoradiotherapy. Hematologic toxicity was high, but was manageable with adequate supportive care. CONCLUSIONS: Because this multimodal treatment, which included a chemotherapeutic regimen with single agents generally used in patients with recurrent disease, had impressive activity in this patient with an advanced adult Wilms' tumor, the issue of further investigation of this alternative schedule is raised. PMID- 9366300 TI - Carboplatin-based versus cisplatin-based chemotherapy in the treatment of surgically incurable advanced bladder carcinoma. AB - BACKGROUND: The carboplatin-based chemotherapeutic regimen M-CAVI (methotrexate, carboplatin, and vinblastine) is active against bladder carcinoma and can be administered to patients who are ineligible to receive cisplatin or doxorubicin. The authors designed a randomized study to evaluate whether M-CAVI offers a therapeutic advantage over the cisplatin-based regimen M-VAC (methotrexate, vinblastine, doxorubicin, and cisplatin) in the treatment of patients with surgically incurable advanced bladder carcinoma. METHODS: Patients with surgically incurable advanced bladder carcinoma were enrolled on a randomized trial comparing M-CAVI, which consists of carboplatin (300 mg/m2 on Day 2, adjusted using Calvert's formula for an area under the curve of 5), methotrexate (30 mg/m2 on Days 1, 15, and 22), and vinblastine (3 mg/m2 on Days 2, 15, and 22) administered every 28 days, versus standard M-VAC. The eligibility criteria included histologically proven bladder carcinoma, surgically incurable disease, and no prior chemotherapy. Patients were treated until disease progression or unacceptable toxicity occurred. RESULTS: From January 1989 to January 1994, 47 assessable patients were included. Seventeen patients had lymph node disease and 30 had distant metastatic disease. Twenty-three patients were randomized to receive M-CAVI and 24 to receive M-VAC. Patient characteristics in the two groups were similar. Overall response rates were 39% (95% confidence interval [CI], 20 62%) for M-CAVI and 52% (95% CI, 30-73%) for M-VAC (P = 0.3), with 3 complete responses observed among patients treated with M-VAC and none among those in the M-CAVI group. M-VAC was associated with more gastrointestinal toxicity, stomatitis, alopecia, and Grade 4 neutropenia than M-CAVI. One toxicity-related death occurred in the M-VAC group. There was a statistically significant difference in median disease-related survival time favoring M-VAC (16 months; range, 6 to 22+) versus M-CAVI (9 months; range, 6 to 14+) (P = 0.03). CONCLUSIONS: M-CAVI is less toxic but less active than M-VAC in the treatment of patients with advanced bladder carcinoma. Carboplatin-based regimens in which carboplatin is administered at the dose range used in the current study should be reserved for patients who cannot tolerate cisplatin treatment. Further research is required to assess the impact of high dose carboplatin in the treatment of this disease. PMID- 9366301 TI - The impact of cancer on the physical function of the elderly and their utilization of health care. AB - BACKGROUND: Controversy about whether cancer has an independent impact on patient quality of life led the authors to evaluate the effects of cancer on a range of quality-of-life and health care utilization measures within an elderly population. METHODS: The authors analyzed a nationally representative sample of 9745 elderly community-based Medicare beneficiaries sampled in the 1991 Medicare Current Beneficiary Survey. Of these, 1647 reported being diagnosed by a physician as having a malignancy that was not of the skin. Multiple logistic regression was used to identify the independent predictors of functional limitation, poor health status, health care utilization, and patient satisfaction with medical care. RESULTS: Cancer was reported by 17% of the elderly. Individuals with cancer reported poorer health, more limitations of the activities of daily living (ADLs) and the instrumental activities of daily living (IADLs), and greater health care utilization than individuals without cancer. For individuals with cancer, difficulty walking (38%) and getting out of a chair (21%) were the most commonly reported ADL limitations, whereas difficulty completing heavy housework (34%) and shopping (17%) were the most common IADL limitations. Carcinomas of the lung, prostate, and colon independently predicted poorer health status. Lung carcinoma was independently associated with more ADL limitations. Lung, bladder, and prostate carcinomas predicted increased health care utilization. Overall, cancer patients were at least as satisfied with their medical care as those without cancer. CONCLUSIONS: Cancer increased the use of health care resources and modestly reduced physical function. By identifying specific connections between cancer and physical function, these findings have implications for improving cancer care. PMID- 9366302 TI - The relationship between primary splenic malignant lymphoma and chronic liver disease associated with hepatitis C virus infection. AB - BACKGROUND: An etiologically important role has been suggested for hepatitis C virus (HCV) infection in the development of B-cell non-Hodgkin's lymphoma (NHL). HCV has been recognized as the major cause of non-A, non-B chronic hepatitis throughout the world. Moreover, the occurrence of primary splenic malignant lymphoma (PSML) has been demonstrated in patients with chronic liver disease. METHODS: In this study, the authors describe three patients with PSML. The clinical, histologic, and immunohistochemical features of the lymphomas were studied. Clonal immunoglobulin heavy chain gene rearrangement was investigated by polymerase chain reaction. RESULTS: All three cases of PSML were detected by imaging studies performed in routine follow-up of cases of chronic liver disease associated with HCV infection. Macronodular lesions were found in the three spleens; two of them were of normal weight and another was moderately enlarged. The former two were the smallest PSMLs reported to date. The histology was B-cell NHL in all cases. All 3 patients were alive after splenectomy with an average follow-up of 51.7 months (range, 35-74 months). CONCLUSIONS: HCV infection may play an etiologic role in the development of splenic B-cell lymphoma. The long survival of the patients in this study may have been due to early splenectomy. PMID- 9366303 TI - Dexamethasone, etoposide, ifosfamide, and cisplatin as second-line therapy in patients with aggressive non-Hodgkin's lymphoma. AB - BACKGROUND: This study analyzed the long term results of a combination of dexamethasone, etoposide, ifosfamide, and cisplatin (DVIP) used at the study center as standard second-line combination therapy in patients with aggressive non-Hodgkin's lymphoma (NHL) after prior exposure to doxorubicin. METHODS: All drugs were given intravenously for 4 consecutive days. The maximum daily doses of etoposide, ifosfamide, and cisplatin were 75 mg/m2, 1200 mg/m2, and 20 mg/m2, respectively. The dexamethasone dose was 20 mg twice daily. Cycles were repeated every 3 weeks. RESULTS: Fifty-six patients were included in the study. Partial response was noted in 18 patients (32%) and complete response (CR) in 18 patients (32%). Pretreatment factors that predicted CR were CR with prior therapy (CR in 17 of 34 in patients with a recurrence vs. 1 of 21 in patients with primary refractory NHL) and age (CR in 12 of 25 patients age < or = 65 years vs. 6 of 31 patients age > 65 years). Median time to treatment failure (TTF) and median survival were 11.5 months and 30 months, respectively, for patients with a CR and 3.5 months and 8 months, respectively, for all patients. Five patients (9%) remained disease free for > 24 months. By multivariate analysis, age was the only independent prognostic factor for TTF, whereas age, serum lactate dehydrogenase, and number of extranodal sites were independent predictors for survival. Myelosuppression (median granulocyte nadir and median platelet nadir of 350/mm3 and 77,000/mm3, respectively) was the major toxicity. There was one possible drug related death associated with myelosuppression. CONCLUSIONS: DVIP is a relatively safe salvage combination therapy in patients with aggressive NHL. Response to first-line therapy and age are the most important predictors for prognosis after the administration of DVIP. This regimen is highly active in patients with recurrent NHL, but relatively ineffective in patients with primary refractory NHL. PMID- 9366304 TI - Blindness in children with neuroblastoma. AB - BACKGROUND: Neuroblastoma is the most common extracranial solid tumor among pediatric patients, and orbital metastatic disease is not uncommon in these children. Physical signs as a consequence of orbital metastases, such as proptosis and periorbital ecchymosis, frequently are encountered. However, subsequent blindness is rare. METHODS: A retrospective study was conducted to determine the incidence, related physical findings, treatment, and outcome of children who developed visual loss during treatment for neuroblastoma. Medical records for a 24-year period (1971-1994) were reviewed to identify these patients. The charts, diagnostic imaging studies, and autopsy material of these patients were reviewed. RESULTS: Of the 450 patients treated for neuroblastoma at the study institution during this period, 47 presented with abnormalities in physical examination of the eye. Eight of these 47 patients and 7 others developed visual loss in at least 1 eye during the first week after diagnosis (n = 5), during primary therapy (n = 6), at recurrence (n 2), or after completion of therapy (n = 2). In ten patients the visual loss was a direct consequence of the primary disease process, whereas a direct relationship between loss of vision and neuroblastoma could not be identified in the remaining five patients. Proptosis and periorbital ecchymosis were the most common associated physical findings. Although ten patients received steroids and eight received radiation, visual loss could not be prevented or reversed in these patients. CONCLUSIONS: Early initiation of effective, multiagent chemotherapy remains the primary approach for the treatment of neuroblastoma and its ophthalmologic complications. Radiation therapy and steroids may have benefit but failed to show good effect in this series. The prevention and treatment of blindness is probably most relevant in infants and children age < 2 years because they have the best chance for cure. PMID- 9366305 TI - Hyperbaric oxygen therapy for radiation-induced brain injury in children. AB - BACKGROUND: Radiation-induced necrosis (RIN) of the brain is a complication associated with the use of aggressive focal treatments such as radioactive implants and stereotactic radiosurgery. In an attempt to treat patients with central nervous system (CNS) RIN, ten patients received hyperbaric oxygen treatment (HBOT). METHODS: Patients presented with new or increasing neurologic deficits associated with imaging changes after radiotherapy. Necrosis was proven by biopsy in eight cases. HBOT was comprised of 20-30 sessions at 2.0 to 2.4 atmospheres, for 90 minutes-2 hours. Sites of RIN included the brain stem (n = 2), posterior fossa (n = 1), and supratentorial fossa (n 7). Histologic types included brain stem glioma (n = 2), ependymoma (n = 2), germinoma (n = 2), low grade astrocytoma (n = 1), oligodendroglioma (n = 1), glioblastoma multiforme (n = 1), and arteriovenous malformation (n = 1). RESULTS: Initial improvement or stabilization of symptoms and/or imaging findings were documented in all ten patients studied and no severe HBOT toxicity was observed. Four patients died, with the cause of death attributed to tumor progression. Five of six surviving patients were improved by clinical and imaging criteria; one patient was alive with tumor present at last follow-up. CONCLUSIONS: HBOT may prove to be an important adjunct to surgery and steroid therapy for CNS RIN. PMID- 9366306 TI - p53 mutation as the second event in juvenile chronic myelogenous leukemia in a patient with neurofibromatosis type 1. AB - BACKGROUND: Young patients with neurofibromatosis type 1 (NF1) are at increased risk of developing various malignancies, most of which are myeloid disorders. The observed loss of NF1 allele in the myeloid malignancies of NF1 patients suggests a role of NF1 as a tumor suppressor gene. Loss of 17p was found to be quite frequent in neural crest tumors from patients with NF1, raising the possibility of p53 tumor suppressor gene involvement in other NF1-related tumors. METHODS: The authors studied mutations in the NF1 and p53 genes, using loss of heterozygosity, single strand conformation polymorphism, heteroduplex and sequencing analyses. RESULTS: An NF1 germline mutation was identified in exon 31 of a child who developed juvenile chronic myelogenous leukemia (JCML). The mutation was segregated within the proband's family. A 14bp deletion at exon 6 of the p53 gene was observed when JCML was diagnosed, and the wild-type p53 allele was lost during progression of the disease. No loss of the normal NF1 allele could be detected. CONCLUSIONS: A germline mutation in the NF1 gene and sequential inactivation of p53 alleles in the malignant clone of JCML raise the possibility of a correlation between NF1 and p53 genes in the tumorigenesis of JCML. PMID- 9366307 TI - Report of a panel on the relationship between public exposure to pesticides and cancer. Ad Hoc Panel on Pesticides and Cancer. National Cancer Institute of Canada. AB - BACKGROUND: Pesticides, which by their nature are biologically active compounds, continue to raise public concern regarding their possible role as important etiologic agents in the development of human cancer. METHODS: To examine this potential role, the National Cancer Institute of Canada convened an Ad Hoc Panel on Pesticides and Cancer to examine the possible contribution of pesticide exposure, particularly in the general population, to the development of human cancer. RESULTS: The Panel focused primarily on exposure in the general population and reviewed a range of studies that addressed issues related to dietary exposure as well as incidental home and garden uses. In addition, the Panel examined the regulatory framework that exists to safeguard the public from potentially carcinogenic pesticides and also reviewed some potential benefits of pesticide use, including the availability of an abundant and low cost supply of fresh fruits and vegetables as an important strategy in the overall mitigation of cancer risk. CONCLUSIONS: The Panel concluded that it was not aware of any definitive evidence to suggest that synthetic pesticides contribute significantly to overall cancer mortality. The Panel also concluded that it did not believe that any increased intake of pesticide residues associated with increased intake of fruits and vegetables poses any increased risk of cancer. The Panel further concluded, among other things, that tobacco use continues to be the most important preventable cause of cancer and premature mortality and thus is an appropriate focus for cancer control strategy. PMID- 9366308 TI - Urodynamic effects of various treatment modalities for benign prostatic hyperplasia. AB - PURPOSE: I studied the effects of various treatments for benign prostatic hyperplasia on urethral resistance. MATERIALS AND METHODS: I reviewed the literature on urodynamic effects of treatments for benign prostatic hyperplasia. Articles that reported pretreatment and posttreatment values of relevant urodynamic parameters were analyzed. Average before and after treatment values of maximum flow rate and detrusor pressure at maximal flow rate for every study were plotted on an Abrams-Griffiths nomogram and classified as obstructed, equivocal or nonobstructed. Average values of maximum flow rate and detrusor pressure at maximal flow rate were calculated for the total number of patients treated by a certain modality. RESULTS: Based on this analysis, the rank order of urodynamic efficacy was that open prostatectomy is more effective in reducing urethral resistance than is transurethral prostatectomy. These treatments diminish obstruction better than laser treatment or transurethral incision of the prostate, which again are more effective than balloon dilation, alpha-blockers or transurethral microwave thermotherapy. Finally, androgen deprivation performs better than placebo treatment. CONCLUSIONS: The rank order of urodynamic efficacy as determined in this analysis shows a high level of agreement with reported rank order of symptomatic efficacy of various modalities. After placebo treatment there is no significant change in urethral resistance. This finding indicates that pressure-flow studies are a sensitive way to compare active to placebo treatment and that pressure-flow studies have excellent long-term reproducibility. PMID- 9366309 TI - Effect of long-term oral L-arginine on the nitric oxide synthase pathway in the urine from patients with interstitial cystitis. AB - PURPOSE: We attempted to determine whether oral L-arginine, the substrate for nitric oxide synthase, increases nitric oxide synthase activity and cyclic guanosine monophosphate (cGMP) levels in the urine from interstitial cystitis patients. Nitric oxide and cGMP are decreased in urine from interstitial cystitis patients and both induce smooth muscle relaxation and immunological responses. Increasing urinary nitric oxide and cGMP may ameliorate interstitial cystitis symptoms. MATERIALS AND METHODS: Eight patients with interstitial cystitis were given L-arginine (1,500 mg. a day) orally for 6 months. Before and during treatment nitric oxide synthase activity and inducible nitric oxide synthase protein, cGMP, nitrate plus nitrite and interleukin 8 (IL-8) levels were measured in urine. RESULTS: After 2 weeks to 1 month of oral L-arginine treatment, urinary levels of nitric oxide synthase related enzymes and products increased significantly, while levels of the cytokine IL-8 were not changed significantly. IL-8 was significantly elevated in interstitial cystitis patients with leukocyte esterase positive urine. CONCLUSIONS: Long-term oral administration of L-arginine increases nitric oxide related enzymes and metabolites in the urine of patients with interstitial cystitis, which is associated with a decrease in interstitial cystitis related symptoms. PMID- 9366310 TI - Cleveland Clinic experience with adrenal Cushing's syndrome. AB - PURPOSE: Cushing's syndrome due to adrenal adenoma or adrenocortical carcinoma is rare. To understand better the clinical and biochemical presentation of this disorder, as well as therapy efficacy and patient survival, we conducted a retrospective review. MATERIALS AND METHODS: Between August 1971 and April 1994, 40 patients presented to our institution with adrenal Cushing's syndrome (27 adenomas and 13 carcinomas). These groups were analyzed with respect to clinical signs and symptoms preoperatively and postoperatively, biochemical analysis, length of postoperative steroid replacement therapy, disease recurrence and patient survival. Followup was obtained by chart review and telephone interviews and averaged 59.6 +/- 66.4 and 47.6 +/- 56.2 months for adenoma and carcinoma patients, respectively. RESULTS: Women predominated in both groups (26 of 27 adenomas, 11 of 13 carcinomas), and tumors affected the left adrenal gland more frequently (19 of 27 adenomas, 9 of 13 carcinomas). Adenoma patients were younger than carcinoma patients (39.6 +/- 14.4 versus 51.5 +/- 16.6 years, p = 0.026) and presented with smaller tumors (3.3 +/- 1.0 versus 8.6 +/- 4.5 cm., p = 0.001). There was a trend toward increased incidence of glucose intolerance among carcinoma patients but no significant differences in clinical signs or symptoms between adenoma and carcinoma patients could be made. Similarly, while there was no significant difference in biochemical evaluation of adenoma versus carcinoma patients, 24-hour urinary free cortisol and serum lactate dehydrogenase levels tended to be higher among carcinoma patients. In addition 17-ketosteroid and dehydroepiandrosterone sulfate levels were more elevated in carcinoma than in adenoma patients, and several adenoma patients actually had subnormal levels. Among adenoma patients mean length of steroid replacement therapy was 16.8 +/- 9.1 months. However, 7 adenoma patients (25.9%) required greater than 24 months of exogenous steroids, and only 1 of these patients was subsequently weaned off steroid replacement. There were no recurrences among adenoma patients, although there was 1 perioperative death due to hypoglycemia. Ten (76.9%) carcinoma patients had recurrences at a mean followup of 33 months. The 3 and 5-year survival rates were 41.5 and 31.2%, respectively. CONCLUSIONS: While presenting signs and symptoms and hormonal analysis may suggest benign or malignant disease, only tumor size and patient age are reliable preoperative indicators of adrenal adenoma versus adrenocortical carcinoma among patients with adrenal Cushing's syndrome. Surgery is curative for adenoma patients, but lifelong steroid replacement may be required. Survival remains poor among carcinoma patients. PMID- 9366311 TI - Adrenocortical carcinoma with intracaval extension. AB - PURPOSE: We describe the presenting features, treatment approach and prognosis of adrenocortical carcinoma with intracaval extension of tumor thrombus. MATERIALS AND METHODS: In addition to 3 patients with adrenocortical carcinoma associated tumor thrombus treated at our institution, we reviewed an additional 26 patients described in the literature from 1972 to 1997 with regard to presentation, management and outcome. RESULTS: We identified 23 female and 6 male patients 6 to 77 years old (mean age 41.3). Of the lesions 24 originated in the right adrenal gland. Mean tumor size was 10.1 cm. and 89% of lesions were at least 9 cm. in greatest dimension. Tumor thrombus extended to the atrium in 15 patients, retrohepatic cava in 7 and subhepatic cava in 7. Flank or abdominal discomfort was the most common presenting complaint and abnormal steroid metabolism was documented in 76% of patients. Cardiac bypass techniques were used in 14 patients and none of the 3 intraoperative mortalities, 2 thromboemboli and 1 exsanguination, occurred using this approach. Eight patients received postoperative mitotane, 6 of whom had no evidence of residual disease at the time of case description. CONCLUSIONS: All patients with large adrenal tumors, especially those arising from the right gland, should undergo careful evaluation of the vena cava for thrombus. The best chance for survival is via complete surgical extirpation which is facilitated by the use of cardiac bypass techniques. There is evidence to support the early use of postoperative mitotane if there is a suspicion of residual or recurrent disease. PMID- 9366312 TI - Endoscopic mapping of renal papillae for Randall's plaques in patients with urinary stone disease. AB - PURPOSE: Papillary "Randall's plaques" are theorized to act as nidi for urinary stone formation. The aim of this study was to document the presence, pattern and distribution of Randall's plaques in patients undergoing endoscopic procedures for urinary stone disease. MATERIALS AND METHODS: Patients undergoing either ureteroscopy or percutaneous nephroscopy for removal of urinary stones underwent endoscopic mapping of accessible calices. These patients were compared to a smaller group of patients undergoing endoscopic procedures for conditions unrelated to urinary stone disease. In patients found to have papillary plaques the presence, location and pattern of plaques were recorded. Plaque formation was correlated with patient age and sex, and primary composition of extricated stone. RESULTS: Endoscopic evidence of papillary Randall's plaques was found in 74% of 57 patients having ureteroscopic (21) or percutaneous (36) stone removal. Of 7 patients having endoscopic procedures for conditions unrelated to urinary stone disease 3 (43%) had evidence of papillary plaques. Plaques were found uniformly throughout all calices and most commonly diffusely scattered over the papillary surface. There was no correlation between patient age or sex and the presence of plaques. The incidence of plaques varied with the primary composition of extracted stones, and was 100% for calcium phosphate and uric acid, 88% for calcium oxalate, 33% for cystine and 20% for struvite. The incidence of papillary plaques was significantly more common in patients with calcium oxalate (88 versus 43%, p = 0.023) and calcium phosphate stones (100 versus 43%, p = 0.009) than patients without a history of urinary stone disease. CONCLUSIONS: The endoscopic incidence of papillary Randall's plaques in patients with urolithiasis varies with the primary composition of formed urinary stones. Randall's plaques are found in the majority of patients with calcium urinary stone disease. Our findings suggest that the presence of papillary plaques is associated with calcium nephrolithiasis and may contribute to the pathogenesis of calcium urinary stones. PMID- 9366313 TI - Simultaneous bilateral percutaneous nephrolithotomy. AB - PURPOSE: We evaluate the results of simultaneous bilateral percutaneous nephrolithotomy. MATERIALS AND METHODS: The charts of 52 patients scheduled for simultaneous bilateral percutaneous nephrolithotomy at the Methodist Hospital of Indiana were retrospectively reviewed. The results of the 48 patients who underwent the procedure were tabulated and analyzed. RESULTS: Mean operative time was 269 minutes and mean hospital stay was 5.6 days. Of the patients 45 were rendered stone-free (96.9% of 96 renal units) and 3 had insignificant debris (fragments less than 4 mm.) unilaterally. Complications were infrequent and included hydrothorax in 5 cases, ureteral obstruction by fragment migration in 2, hematuria causing clot retention in 2, blood transfusion in 2 and ureteral perforation with a guide wire in 1. CONCLUSIONS: Simultaneous bilateral percutaneous nephrolithotomy is a well tolerated, safe, cost-effective and expeditious approach to patients with bilateral renal calculi requiring percutaneous nephrolithotomy. PMID- 9366314 TI - Potassium-magnesium citrate is an effective prophylaxis against recurrent calcium oxalate nephrolithiasis. AB - PURPOSE: We examined the efficacy of potassium-magnesium citrate in preventing recurrent calcium oxalate kidney calculi. MATERIALS AND METHODS: We conducted a prospective double-blind study of 64 patients who were randomly assigned to receive placebo or potassium-magnesium citrate (42 mEq. potassium, 21 mEq. magnesium, and 63 mEq. citrate) daily for up to 3 years. RESULTS. New calculi formed in 63.6% of subjects receiving placebo and in 12.9% of subjects receiving potassium-magnesium citrate. When compared with placebo, the relative risk of treatment failure for potassium-magnesium citrate was 0.16 (95% confidence interval 0.05 to 0.46). Potassium-magnesium citrate had a statistically significant effect (relative risk 0.10, 95% confidence interval 0.03 to 0.36) even after adjustment for possible confounders, including age, pretreatment calculous event rate and urinary biochemical abnormalities. CONCLUSIONS: Potassium-magnesium citrate effectively prevents recurrent calcium oxalate stones, and this treatment given for up to 3 years reduces risk of recurrence by 85%. PMID- 9366315 TI - Adjuvant mitomycin C following endoscopic treatment of upper tract transitional cell carcinoma. AB - PURPOSE: A variety of topical agents have been used for transitional cell carcinoma of the upper tract. Mitomycin C has limited systemic absorption when given intravesically because of its high molecular weight. We reviewed our experience with mitomycin C following endoscopic treatment of upper tract transitional cell carcinoma. MATERIALS AND METHODS: Since 1991, 19 patients (21 renal units) have undergone a total of 28 treatments with mitomycin C for high volume, recurrent or multifocal transitional cell carcinoma. Of the 19 patients 12 had an absolute indication for nephron sparing treatment. Following ureteroscopic biopsy and treatment of upper tract transitional cell carcinoma, 40 mg. mitomycin C in 3 divided doses was instilled via a ureteral catheter, which was clamped between doses to give an exposure time of 30 minutes. Eighteen patients have undergone ureteroscopic surveillance following a total of 26 treatments. RESULTS: No systemic side effects occurred during or after treatment with mitomycin C. One patient had a prominent local inflammatory reaction following neodymium:YAG ablation and mitomycin C treatment of a renal pelvic tumor. The average size of the treated tumors was 17 mm. (range 5 to 30). The grade of the tumors (when known) was 1 in 5 patients, 1 to 2 in 2, 2 in 8 and 3 in 4. Most tumors were treated with either neodymium:YAG (6 cases) or holmium:YAG laser (8) or a combination of both (8). Following 1 to 4 treatments with mitomycin C 11 of 19 evaluable renal units (58%) were rendered free of disease. Six of those 11 renal units (54%) had an ipsilateral recurrence after a mean of 30 months of followup, 4 of which were treated endoscopically, and 7 (64%) are now disease-free without extirpative surgery. Four patients have undergone nephroureterectomy for persistent or recurrent disease. No patient has suffered local or distant progression of disease. CONCLUSIONS: Instillation of mitomycin C for upper tract transitional cell carcinoma appears to be safe and can be considered for adjuvant treatment in select cases. More data are necessary to determine its efficacy. PMID- 9366316 TI - Versatility of the adult psoas hitch ureteral reimplantation. AB - PURPOSE: The psoas hitch ureteral reimplant has been described in the literature as an excellent method to restore ureterovesical continuity in patients with ureteral defects of various etiologies. However, long-term data on the durability of this procedure are lacking. We retrospectively reviewed patients who underwent ureteral reconstruction using the psoas hitch reimplantation to determine long term efficacy. MATERIALS AND METHODS: Ureteral reimplantation in the adult is frequently performed in the setting of ureteral tissue loss secondary to resection or injury. The psoas hitch reimplantation is a simple, versatile technique that avoids the inclusion of intestinal segments and can be used in most patients requiring reimplantation. Indications for surgery and the long-term followup were examined in 20 patients undergoing reimplantation using the psoas hitch. RESULTS: The indications for ureteral reconstruction included surgical injury in 13 cases, recurrent pyelonephritis with reflux in 1, obstruction secondary to cancer in 2, trauma in 1, retroperitoneal fibrosis in 1 and ureteral stricture in 2. At followup of 1 to 14 years (mean 6) 17 patients have not required further intervention for urological problems and have retained normal renal function. In the 2 patients with cancer ileal conduit was performed later and in 1 flank pain persisted despite negative urological evaluation. CONCLUSIONS: Psoas hitch ureteral reimplantation can be used successfully for bridging various ureteral defects in difficult clinical situations. Adequate renal and bladder mobilization will allow reconstruction despite long ureteral defects. PMID- 9366317 TI - The role of oxybutynin in spinal cord injured patients with indwelling catheters. AB - PURPOSE: The long-term benefits of oral oxybutynin in spinal cord injured patients with indwelling catheters is unknown. We reviewed our experience with this population of men and present the results of our analysis. MATERIALS AND METHODS: A total of 109 male spinal cord injured patients at the Houston Veterans Affairs Medical Center have been treated with chronic indwelling catheters (80 transurethral and 29 suprapubic). Thirty-eight patients (35%) were identified as using oxybutynin on a regular basis. These patients were compared to those not using oxybutynin with regard to urodynamic parameters and upper tract deterioration. Specifically examined were bladder compliance, bladder leak point pressure, vesicoureteral reflux, hydronephrosis, urolithiasis, febrile urinary tract infections and serum creatinine greater than 2 mg./dl. RESULTS: The mean duration of indwelling catheter use was 11.9 years (12.4 without oxybutynin and 10.9 on oral oxybutynin). Of the 31 patients with normal compliance (greater than 20 ml./cm. water), 24 (77%) were using oxybutynin (p = 0.001). Bladder leak point pressures were abnormal (greater than 35 cm. water) in 5 of 32 patients (16%) on oxybutynin versus 34 of 60 (57%) without it (p <0.001). Hydronephrosis was present in 15 of 66 patients (23%) without oxybutynin versus 1 of 36 (3%) with oxybutynin (p = 0.009). Febrile urinary tract infections occurred in 4 of 35 patients (11%) versus 17 of 62 patients (27%) with or without oxybutynin, respectively (p = 0.077). No significant differences were found between the 2 groups with regard to reflux, renal scars, stones or elevated serum creatinine. CONCLUSIONS: It appears that regular use of oxybutynin may be beneficial in spinal cord injured patients who require chronic indwelling catheters for bladder management. Our analysis reveals that patients who take oxybutynin regularly have better bladder compliance, lower bladder leak point pressures and less hydronephrosis. Until a prospective, randomized trial reveals contradicting outcomes, empiric use of oxybutynin in all spinal cord injured patients requiring chronic indwelling catheters seems justified. PMID- 9366318 TI - Intravesical capsaicin as a treatment for refractory detrusor hyperreflexia: a dual center study with long-term followup. AB - PURPOSE: We described the long-term outcome of intravesical capsaicin instillations in patients with urinary incontinence and compared its efficacy in 2 similar populations of patients with multiple sclerosis in a dual center study. MATERIALS AND METHODS: During 5 years 79 patients with intractable urinary incontinence have been treated with intravesical capsaicin. The majority of patients had spinal cord disease due to multiple sclerosis but 4 were neurologically normal. Cystometry was performed before and 4 to 6 weeks after intravesical instillation of 1 to 2 mmol./l. of capsaicin in 30% ethanol in saline. Instillations of vehicle (30% ethanol in saline) alone were carried out in 5 patients. RESULTS: In patients with phasic detrusor hyperreflexia complete continence was achieved in 44%, satisfactory improvement occurred in 36% and treatment failed in 20%. Clinical benefit from a single instillation lasted 3 to 6 months and was repeated in some patients with similar improvement. Capsaicin was ineffective in patients with poor bladder compliance and in neurologically normal patients with sensory urgency and detrusor instability. There was no clinical or urodynamic improvement in patients treated with vehicle alone. There have been no long-term complications. CONCLUSIONS: Our study shows that repeated instillations of intravesical capsaicin are effective in treatment of patients with detrusor hyperreflexia due to spinal cord disease and that effectiveness of the treatment persists at least 3 to 5 years. PMID- 9366319 TI - Urodynamic effects of intravesical resiniferatoxin in humans: preliminary results in stable and unstable detrusor. AB - PURPOSE: Resiniferatoxin, a substance isolated from some species of euphorbia, a cactus-like plant, presents pharmacological effects similar to those of capsaicin. We studied the urodynamic effects of intravesical resiniferatoxin* in normal subjects and patients with unstable detrusor contraction to provide insight into the action mechanism of the molecule on sensory neurons and possible future pharmacological and clinical use. MATERIALS AND METHODS: A total of 15 subjects with normal (8 patients) or unstable detrusor muscle (1 with detrusor instability and 6 with detrusor hyperreflexia) underwent urodynamic assessment during and after intravesical instillation of resiniferatoxin. Volume required to elicit the first desire to void, maximum bladder capacity and maximum bladder pressure were recorded during instillation of resiniferatoxin at a flow rate of 20 ml. per minute (normal subjects) or 15 minutes after instillation of 30 cc of a saline solution containing 10(-8) M. of resiniferatoxin and kept for 30 minutes in patients with unstable detrusor. The experiment was examined by the analysis of variance for repeated measures and post hoc comparisons were performed by Tukey-Kramer procedure. A p value <0.05 was accepted as significant. RESULTS: Resiniferatoxin did not decrease the volume required to elicit the first desire to void and did not produce warm or burning sensations at the suprapubic/urethral level during infusion in subjects with normal detrusor function. In patients with bladder hyperactivity mean bladder capacity increased from 175.28 ml. plus or minus standard deviation 36.05 to 280.85 ml. plus or minus standard deviation 93.33 (p <0.01) immediately after treatment, and no significant modification of bladder pressure was recorded. Four weeks after treatment, bladder capacity remained increased in 2 patients but mean capacity did not increase significantly from 175.28 ml. plus or minus standard deviation 36.053 to 216.71 plus or minus standard deviation 86.91. The 2 patients with stable increase of bladder capacity reported significant clinical improvement of frequency, nocturia and incontinence 4 weeks later. CONCLUSIONS: Our results suggest that in humans there may be substantial differences in urodynamic effects between resiniferatoxin and capsaicin when the drugs are instilled into the bladder. Further studies, in vitro and in vivo, are necessary to define the pharmacological and clinical effects of resiniferatoxin. Because resiniferatoxin did not produce warm or burning sensations at the suprapubic/urethral level during infusion and seems to have rapid desensitization, it could be an interesting alternative to intravesical capsaicin in the treatment of select cases of bladder hyperactivity. PMID- 9366320 TI - Should we be using chili pepper extracts to treat the overactive bladder? PMID- 9366321 TI - Rapid detection of bladder cancer: a comparative study of point of care tests. AB - PURPOSE: We assessed sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the bladder tumor antigen (Bard BTA), fibrinogen/fibrin degradation products (AuraTek FDP), urinary cytology and hemoglobin dipstick tests in the urine of patients presenting to a urology clinic. MATERIALS AND METHODS: A total of 130 patients (60 with bladder cancer) provided a urine sample, which was divided into appropriate aliquots for each of the tests cited above. The endoscopist, pathologist, cytologist and the person performing the BTA/FDP/hemoglobin dipstick were blinded as to the results of the other tests, and the tests were read independently by a second blinded evaluator. RESULTS: Comparative results demonstrate a clear superiority of FDP in sensitivity (81%) and overall accuracy in bladder cancer detection (p = 0.0001) while cytology and BTA were marginally better than FDP in specificity. CONCLUSIONS: The anticipated lack of specificity of the hemoglobin dipstick was confirmed as well as the inadequacy of urinary cytology, particularly in the well differentiated tumors. Our findings with BTA were disappointing. The superiority of the FDP, first demonstrated here, was particularly striking in its ability to detect even well differentiated tumors. The simplicity and significantly better overall performance of FDP make it a reliable test for detection of transitional cell carcinoma of the bladder and a potential alternative to urinary cytology with important implications for clinical practice and health economics. PMID- 9366323 TI - Data interpretation and integration of new tests into clinical practice. PMID- 9366322 TI - The bladder tumor antigen (BTA) test compared to voided urine cytology in the detection of bladder neoplasms. AB - PURPOSE: Tests to detect recurrent bladder neoplasms are limited and none is consistently accurate. Recent studies suggest that the bladder tumor antigen (BTA) test, an agglutination reaction for basement membrane complexes, is superior to voided urine cytology in clinical practice. We compared BTA and voided urine cytology to bladder washings and cystoscopy, emphasizing diagnostic yield among patients with causes of basement membrane complexes other than bladder cancer. MATERIALS AND METHODS: Random voided urine specimens from 67 patients with a history of bladder neoplasms were collected before cystoscopy and bladder washing. Urine also was obtained from 34 patients with inflammatory bladder conditions including 5 with a history of prostate cancer. Each urine was tested for BTA according to a commercial kit. Positive results were indicated by yellow on a test pad. Blinded to all other results, each urine and each bladder washing were examined microscopically, and a positive test had malignant/suspicious cells. Bladder biopsies were performed when endoscopic lesions were seen. Specimens were grouped into 4 categories: group 1--biopsy proved bladder neoplasm, group 2--history of bladder cancer but not biopsy proved, group 3--history of prostate cancer and group 4--no history of urological cancer. RESULTS: Voided urine cytology was positive in 54% of specimens from patients with biopsy proved bladder neoplasms compared to 29% for BTA. Relative yield for voided urine cytology versus BTA was not changed if all group 2 cases having a positive bladder washing and positive cystoscopy were assumed to have bladder cancer, nor was relative yield altered by subsequent short-term followup. Of voided urine specimens 14% from group 1 patients and 41% from group 2 patients had scant cells. Overall diagnostic yield was superior for bladder washing. False positive BTA occurred in 7 of 34 patients with no history of urological or prostate cancer. There were no false-positive voided urine cytology interpretations in these groups. CONCLUSIONS: BTA is not superior to voided urine cytology in detecting bladder neoplasms and may be limited by false-positive reactions in patients with other causes of basement membrane complexes in urine. Voided urine samples may be limited by high frequency of hypocellularity. Of 34 patients with a hypocellular urine specimen 4 had biopsy proved bladder cancer. Bladder washing yields best results but requires instrumentation. No test, including cystoscopy, is accurate always. PMID- 9366324 TI - Detection of bacillus Calmette-Guerin in the blood by the polymerase chain reaction method of treated bladder cancer patients. AB - PURPOSE: Following intravesical bacillus Calmette-Guerin (BCG) instillation, we attempted to detect BCG in the blood using the polymerase chain reaction (PCR) method and correlate these findings with the occurrence of major complications due to this treatment. MATERIALS AND METHODS: Intravesical BCG immunotherapy was given to 22 consecutive patients with superficial bladder tumors. In 2 patients the BCG instillation had to be discontinued due to serious side effects of therapy. Blood samples (252 aliquots) were obtained from 126 BCG courses in 22 cases, and 2 additional samples (4 aliquots) were obtained from 1 patient 1 and 3 months after cessation of therapy. All blood samples were analyzed by the PCR technique for detection of deoxyribonucleic acid tuberculosis Mycobacterium tuberculosis. RESULTS: Of the 126 blood samples 9 (7.1%) were PCR positive for M. tuberculosis. These 9 positive samples belonged to 3 patients, all of whom were among those 4 patients who had major clinical side effects. CONCLUSIONS: We demonstrated that rapid and sensitive detection of mycobacteremia by PCR correlated with the clinical course of these patients. We also demonstrated that PCR can be used to monitor BCG in the blood after antituberculous therapy. The early, fast and accurate diagnosis of BCG in the blood by PCR may alter the serious clinical course of these patients by initiation of specific treatment early. However, further extensive studies are needed to validate these results. PMID- 9366325 TI - Radical cystectomy in the octogenarian. AB - PURPOSE: We evaluated the morbidity and outcome of cystectomy and urinary diversion in patients 80 years old or older with invasive bladder cancer. MATERIALS AND METHODS: We reviewed the records of all patients older than 80 years who underwent cystectomy during the last 15 years. Of 1,186 cystectomies 44 patients (4%) were identified. Patients were evaluated for complications, mortality and functional status after surgery. RESULTS: The 44 patients had a median age of 81 years (range 80 to 87). Of the patients 78% had significant co morbidity, including 41% with 2 or more medical problems. Median hospital stay was 14 days, with 20% of the patients requiring intensive care for 24 hours. There was a 51% complication rate including 25% due to surgical complications and 26% from underlying medical illness. Operative mortality was 4.5%. Within 6 months of surgery 66% were rehospitalized for medical or surgical reasons. Median survival time was 25 months. Median performance status before and after surgery decreased slightly from 70 to 65. CONCLUSIONS: The results of this study support the use of cystectomy in octogenarians with invasive bladder cancer. Surgery can be accomplished with acceptable morbidity and mortality. Radical cystectomy in this population offers the best opportunity for sustained disease-free quality survival. PMID- 9366326 TI - The effect of nerve sparing cystectomy technique on postoperative continence after orthotopic bladder substitution. AB - PURPOSE: Continence after orthotopic bladder substitution may be influenced by characteristics of the reservoir and of the sphincter mechanism. Autonomic innervation probably contributes to pressure generation by the sphincter mechanism at rest. We therefore examined the effect of nerve sparing cystectomy technique on continence in 165 consecutive men who underwent cystectomy and construction of an ileal low pressure reservoir and were followed regarding continence for at least 3 months postoperatively. MATERIALS AND METHODS: Nerve sparing was attempted bilaterally in 20 men, unilaterally in 96 and not at all in 49. Patients were followed prospectively and completed regular voiding diaries, including details of continence. Postoperative sexual potency was ascertained by questionnaire. The effects of attempted nerve sparing and of age on continence were examined in Kaplan-Meier models and in Cox's proportional hazards models. RESULTS: Median times to continence during the day and at night for all men were 3 and 9 months, respectively. Continence differed significantly between patients with attempted nerve sparing and no attempt at nerve sparing (day, p = 0.003 and night, p = 0.001, log rank test) and between men less than 65 years old and those older than 65 (day, p = 0.037 and night, p = 0.005, log rank test). In the multivariate analysis, attempted nerve sparing was significantly associated with improved continence by day (t = 1.96) and by night (t = 1.98). CONCLUSIONS: These data suggest that attempted nerve sparing is associated with improved urinary continence after orthotopic bladder substitution. PMID- 9366327 TI - Does prostate transitional cell carcinoma preclude orthotopic bladder reconstruction after radical cystoprostatectomy for bladder cancer? AB - PURPOSE: We determined if urethral preservation and orthotopic bladder replacement in patients with transitional cell carcinoma within the prostatic urethra or prostate placed these patients at risk for urethral recurrence or death. MATERIALS AND METHODS: The clinical course of all patients undergoing urethral preservation and orthotopic bladder replacement was reviewed. The urethra was sacrificed only if the distal prostatic urethral margin was positive for transitional cell carcinoma. The pathological T stage and the grade of the primary malignancy, local recurrence, site of recurrence (urethral, pelvic, distant) and death were documented. RESULTS: Of 81 patients 70 were evaluable (June 1996) with a mean followup of 35 months. Of the 70 patients 48 were alive without evidence of disease for a mean of 38 months (range 8 to 107) and 5 died without evidence of disease. Eight of these 53 patients (15%) had prostatic involvement (carcinoma in situ in 6, intraductal carcinoma in 1 and stromal invasive transitional cell carcinoma in 1). Of the 70 patients 17 had disease recurrence (13 died of disease and 4 are alive, 1 of whom had urethral recurrence without initial prostatic transitional cell carcinoma). Of the 17 patients (35%) 6 had transitional cell carcinoma prostatic involvement (carcinoma in situ in 4 and stromal invasion in 2), and 5 of these 6 died, none with or of urethral recurrence but of the primary bladder pathology. Of these 5 patients 1 had stromal invasive transitional cell carcinoma of the prostate and experienced a bulbar urethra recurrence at 1 month and a pelvic recurrence at 3 months, and died at 5 months. Death was not secondary to the urethral recurrence. Thus, of the 14 patients who had prostatic transitional cell carcinoma, only 1 had urethral recurrence (7%), and this recurrence did not present as the cause of death. CONCLUSIONS: The guidelines for urethral resection can be relaxed, increasing the opportunities for orthotopic reconstruction, without placing the patients at increased risk for death of transitional cell carcinoma. PMID- 9366328 TI - Pelvic floor electrical stimulation in the treatment of stress incontinence: an investigational study and a placebo controlled double-blind trial. AB - PURPOSE: We designed an investigational study and a placebo controlled, double blind study to evaluate the usefulness of electrical pelvic stimulation in stress incontinence. MATERIALS AND METHODS: We studied 44 patients with stress incontinence (six men and 38 women, age 63 +/- 13), including 9 patients in the investigational study and 35 in the double-blind study. We used 50 Hz. square waves of 1 ms. pulse duration for stimulation. A vaginal electrode was used in women and an anal electrode in men. Urethral pressure profile before, during and after 15-minute stimulation was measured in the investigational study. In the double-blind trial an active device and a dummy device were used, and efficacy was judged from patient impressions, records in frequency/volume chart, results of 1-hour pad test and urodynamic parameters after 4-week treatment. RESULTS: In the investigational study maximum urethral closure pressure (mean plus or minus standard deviation) before, during and after stimulation was 44.4 +/- 17.5, 64.5 +/- 28.8 and 46.8 +/- 25.6 cm. water, respectively. This parameter significantly increased (p = 0.0275) during stimulation. In the double-blind trial patient impressions were good in 60% of the active device group and 8% of the dummy device group (p = 0.0051). For the pad test significant improvement was noted in the active device group (p = 0.0100). Cure rate was 45% in the active device group and 7.7% in the dummy device group. There were significantly more cured or improved patients for frequency of leakage (p = 0.0196) and pad test (p = 0.0100). CONCLUSIONS: Electrical stimulation is effective for the treatment of stress incontinence. PMID- 9366329 TI - Collagen injection therapy for post-radical retropubic prostatectomy incontinence: role of Valsalva leak point pressure. AB - PURPOSE: We retrospectively evaluated the role of Valsalva leak point pressure as a predictor of successful management of post-radical retropubic prostatectomy incontinence with collagen injection. MATERIALS AND METHODS: Urodynamic studies and Valsalva leak point pressures of 31 men who received retrograde collagen injection for post-radical retropubic prostatectomy incontinence were reviewed. Patients were interviewed before and after treatment to assess pad use and the American Urological Association quality of life index (scale 0 to 6). Parameters for success were postoperative quality of life score 3 or less or 50% or greater decrease in pad use and that the patient would recommend collagen therapy to someone else. RESULTS: Of 31 patients 11 (35%) met the criteria for success, 2 (6%) were completely dry and 9 (29%) were improved. Successfully treated patients had a mean Valsalva leak point pressure of 64.0 cm. water compared to 42.2 cm. water in the failure group (p <0.01). Of patients with Valsalva leak point pressure of 60 cm. water or greater, 70% responded favorably to collagen injection (positive predictive value), while 81% with Valsalva leak point pressure less than 60 cm. water had treatment failure (negative predictive value) (p <0.02). There were no other statistically significant differences between those successfully treated with collagen injection and those in whom treatment failed, including mean age (62.7 to 68.1 years), mean volume of collagen (26.1 to 28.9 ml.), mean number of treatment sessions (2.45 to 2.65), mean followup (14.9 to 15.1 months), preoperative quality of life score (5.1 to 4.9), and preoperative pads per day (4.0 to 3.37). CONCLUSIONS: Our data suggest that collagen injection improves 35% but cures a minority of patients (less than 10%) with post-radical retropubic prostatectomy incontinence. A pretreatment Valsalva leak point pressure of 60 cm. water or greater has high predictive value for a beneficial outcome after collagen injection. We propose a role for Valsalva leak point pressure to select men cost-effectively with post-radical retropubic prostatectomy incontinence for therapy with collagen injection. PMID- 9366331 TI - Inlay-onlay flap urethroplasty for hypospadias and urethral stricture repair. AB - PURPOSE: The absence of a segment of the urethral plate renders the onlay urethroplasty procedure impossible. The plate may be too short (in hypospadias), or scarred after previous repair or due to a dense urethral stricture. A modified approach with restoration of urethral plate continuity is proposed instead of the tubularized island flap associated with higher complication rates. MATERIAL AND METHODS: In 12 of 20 patients with a partially deficient urethral plate the inlay onlay preputial island flap was used. The wider part of the flap is inlaid in place of the missing plate and anastomosed to the residual plate. Formation of the urethra is then completed with standard onlay overlapping of the flap. In another 8 patients the combined (partially tubularized in advance) tube-onlay flap was used. RESULTS: The inlay-onlay flap technique was used in 3 new hypospadias patients, in 4 with a scarred, hair-bearing plate after previous operations and in 5 with virtually no urethral plate because of a dense urethral stricture. No urethral complications were encountered. Of the 8 patients undergoing the combined tube-onlay repair 3 had complications, including meatal stenosis (2) and partial dehiscence (1). CONCLUSIONS: Inlay-onlay flap urethroplasty allows correction of complex cases of hypospadias or urethral stricture with a partially deficient urethral plate in 1 stage with a low complication rate. PMID- 9366330 TI - Preservation of the anterior urethral ligamentous attachments in maintaining post prostatectomy urinary continence: a comparative study. AB - PURPOSE: The impact was determined on post-prostatectomy urinary incontinence of a technique preserving the anterior attachments of the proximal urethra to the posterior pubis by comparison to the results of other surgical methods. MATERIALS AND METHODS: Urinary continence in 51 patients undergoing preservation of the anterior urethral attachments was compared to that of 70 patients undergoing an anatomical prostatectomy with resection of the bladder neck, 55 patients with preservation of the bladder neck and 14 patients undergoing a dorsal vein gathering procedure. Comparisons were made for rate of total continence, time to return of continence, incidence of extra organ disease and operative blood loss. RESULTS: Total continence at 1 year was 84.3%, 89.1%, 85.7% and 100% respectively. Immediate total continence after catheter removal was seen in 25.5% after preservation of the anterior urethral attachments, 80.4% at 3 months compared to 41.4%, 50.9% and 50% at 3 months for anatomical prostatectomy with bladder neck resection, preservation and dorsal vein gathering. Clinical staging with the incidence of specimen confined disease was similar in all groups. Mean operative blood loss was 1,031 ml. for those patients undergoing anatomical prostatectomy compared to 681 ml. for those with preservation of the anterior urethral attachments. CONCLUSIONS: Preservation of the anterior urethral attachments results in improved urinary continence and lower operative blood loss without an increase in positive surgical margins. PMID- 9366332 TI - Phallus preservation for urethral cancer: subcutaneous penectomy. AB - PURPOSE: We present a new alternative to amputating penectomy, subcutaneous penectomy, in the male patient with urethral cancer. MATERIALS AND METHODS: The surgical management and followup of 3 men with squamous cell cancers of the urethra are reviewed. RESULTS: At 22, 9 and 6 months postoperatively all patients were without evidence of local recurrence and were satisfied with phallic appearance. In 1 of 2 patients in whom the dorsal neurovascular bundle was not preserved there was distal glans necrosis and wound separation which resolved after conservative management. One of the 3 patients is contemplating phallus reconstruction. The patient who had pelvic lymph node metastases before penectomy died of metastatic complications without local failure 9 months postoperatively. CONCLUSIONS: Phallus preservation in men with urethral cancer can be accomplished successfully with this type of procedure. The dorsal neurovascular bundle should be preserved when feasible. We contend that the cosmetic and potential reconstructive outcomes are superior to amputation without sacrificing cancer therapy in the appropriately selected patient. PMID- 9366333 TI - A surgical algorithm for the treatment of Peyronie's disease. AB - PURPOSE: When conservative treatment of Peyronie's disease fails, the optimal surgical approach is not well defined. Multiple factors, including penile rigidity, degree of curvature, shaft narrowing with hinge effect and erectile response to vasoactive penile injections, indicate that no single approach is likely to solve the problem in all patients. MATERIALS AND METHODS: A surgical algorithm was developed for the treatment of Peyronie's Disease based on our previous surgical experience, which was used prospectively in 103 consecutive men. Penile straightening without prosthesis was offered to patients with adequate rigidity for coitus. Specifically, for mild to moderate curvature less than 60 degrees without hourglass or hinge effect deformity the less complicated tunica albuginea plication procedure was performed. For those men with more severe, complex curvature greater than 60 degrees and/or significant hourglass or hinge effect deformity plaque incision or partial excision with dermal grafting was offered to limit shaft shortening and to reconstruct a shaft with normal caliber to provide optimal axial support during intromission. For men with poor sexually induced erections and/or inadequate response to intracavernosal pharmacotherapy penile prosthesis placement was recommended to provide adequate straightening and rigidity. RESULTS: Of 22 patients who underwent plication procedures 91% remained potent and the penis remained straight postoperatively. Of 52 patients who underwent an incision or partial excision and grafting procedure, 48 had dermal grafts with the penis remaining straight in 94% and 75% remaining potent postoperatively. A total of 29 patients received a prosthesis with the penis remaining straight in 93% who were sexually active postoperatively. During the follow up period (mean 22.3 months) there have been no mechanical device failures. CONCLUSIONS: Surgical outcome was optimized with this algorithm, which correlates surgical complexity to the underlying severity of the penile deformity and erectile capacity. PMID- 9366334 TI - Reconstruction of deformities resulting from penile enlargement surgery. AB - PURPOSE: More than 30 patients presented for reconstruction of penile deformities secondary to penile enlargement surgery performed by other physicians. Lengthening was performed by releasing the suspensory ligament of the penis and advancing pubic skin with a V-Y advancement flap. Girth was increased by injecting autologous fat. Specific complaints relating to the lengthening procedure involve hypertrophic and/or wide scars, a proximal penile hump from a thick, hair-bearing V-Y flap, and a low hanging penis. Complications relating to autologous fat injections include disappearance of fat, penile lumps and nodules, and shaft deformities. The repair of these deformities is described. MATERIALS AND METHODS: From 1994 through October 1996, 19 men underwent 24 various combinations of reconstructive operations, such as scar revisions, V-Y advancement flap reversal, and removal of fat nodules and asymmetrical fat deposits. RESULTS: Penile appearance and function were improved. Complications include 1 hematoma requiring drainage, minor wound complications and 1 inadequately reversed V-Y flap. CONCLUSIONS: The methods of various repairs are discussed, including reconstructive limitations, timing and staging. Significant improvement can be achieved with proper reconstruction of penile deformities. PMID- 9366335 TI - Mumps orchitis: report of a mini-epidemic. AB - PURPOSE: The incidence of mumps orchitis has declined dramatically since the introduction of vaccination. While in the past cases of mumps have only been seen occasionally at our institution, recently there has been a sharp increase in the number of confirmed cases. MATERIALS AND METHODS: Between June 1995 and April 1996, 11 patients with severe mumps orchitis were hospitalized at our clinic. Medical history, therapeutic measures and clinical outcome were recorded for each patient. RESULTS: All patients showed marked scrotal swelling with a temperature above 38.5 C. Serum C-reactive protein was significantly elevated (mean 140 mg./l.). The vaccination status of 1 of the 11 patients (9%) was unknown. Medical records from the remaining 10 patients indicated that they had not been vaccinated. Nine patients (82%) had a typical mumps parotitis preceding the orchitis. In 2 patients the clinical diagnosis of parotitis was uncertain but mumps serology was positive. None of the patients showed other manifestations of mumps. Antibodies to the mumps virus (IgG and IgM) were determined in 6 patients and positive in all cases. The average interval between parotitis and onset of orchitis was 10 days. All patients were hospitalized for an average of 6 days. Treatment included bed rest with local cooling, scrotal support and systemic treatment with nonsteroidal anti-inflammatory drugs. Ciprofloxacin or clavulanic acid/amoxicillin was administered as bacterial orchitis could not be excluded at initial presentation. The mean time to cessation of fever was 3.6 days (range 3 to 5). Antibiotics were administered for an average of 8.8 days (range 7 to 13) and anti-inflammatory drugs were given an average of 8.6 days (range 7 to 11). One patient required scrotal exploration. CONCLUSIONS: Since the introduction of a vaccine against the mumps virus there is a diminished risk for mumps and its complications. However, in case of scrotal swelling mumps orchitis should still be considered. Despite vaccination mumps has not been erradicated. Therefore, continued vaccination should be considered an important step in minimizing clinical outbreaks and working towards a possible eradication of this disease in the future. PMID- 9366336 TI - Serum free prostate specific antigen and prostate specific antigen density measurements for predicting cancer in men with prior negative prostatic biopsies. AB - PURPOSE: We examined the usefulness of measurements of free prostate specific antigen (PSA) and PSA density for predicting prostate cancer in men who had had a prior negative biopsy, a serum PSA level of 4.1 to 10.0 ng./ml. and benign findings on prostate examination. MATERIALS AND METHODS: We measured percent free serum PSA and PSA density in 163 male volunteers age 50 years or older who were advised to have repeat prostatic biopsies for a serum PSA level of 4.1 to 10.0 ng./ml. RESULTS: Of 99 men who had repeat biopsies 20 (20%) had prostate cancer detected. Prostate cancer was significantly associated with lower free PSA level and higher PSA density, with overlap in 83% of the cases. The use of percent free PSA cutoffs of 28 and 30% would have detected 90 and 95% of cancers, respectively, and avoided 13 and 12% of the biopsies, respectively. PSA density cutoffs of 0.10 and 0.08 would have detected 90 and 95% of cancers, respectively, and avoided 31 and 12% of biopsies, respectively. CONCLUSIONS: Free PSA and PSA density predict prostate cancer in men who have had prior negative prostatic biopsies, serum PSA levels of 4.1 to 10.0 ng./ml. and a benign prostate examination. Both parameters may be used to avoid unnecessary biopsies with an acceptable decrease in sensitivity. Further studies are needed to determine cutoffs to be used in clinical practice. PMID- 9366337 TI - Optimization of prostate biopsy strategy using computer based analysis. AB - PURPOSE: We evaluated and optimized the detection of cancer by prostate biopsies. We developed a stochastic computer simulation model of ultrasound guided biopsies using mathematically reconstructed radical prostatectomy specimens. Use of this technique allows rapid evaluation of a variety of factors for their effect on prostate biopsy results. We used this model to analyze the effectiveness of sextant biopsies, which have been widely adopted in clinical practice. We also analyzed other biopsy schemes. MATERIALS AND METHODS: A total of 607 tumor foci from 180 serially sectioned whole mount radical prostatectomy specimens was mapped and digitized. The cancers had been clinically diagnosed by a variety of biopsy strategies. Simulated parasagittal sextant biopsies were performed for each case. Forty simulation runs (each consisting of a set of 6 biopsies) were performed for each prostate, with realistic random variations in sextant biopsy localization programmed in each run. Cancer detection by biopsy was considered reliable if 90% of the simulation runs for each prostate were positive for cancer. A summary algorithm was used to map the tumor foci. RESULTS: Simulation of sextant biopsies demonstrated reliably detected cancer in only 107 of 147 patients (73%) in whom total tumor volume was greater than 0.5 cc. There was little correlation between total length of cancer in biopsy cores and tumor volume. Change of biopsy angle from 30 to 45 degrees did not result in significantly increased detection rates. Similarly, placing all biopsies more laterally did not increase overall detection rates. When we mapped tumor foci from the 40 cases in which sextant biopsies did not reliably detect tumor, we found that the foci were distributed in areas not biopsied by the sextant method, that is the transition zone, midline peripheral zone and inferior portion of the anterior horn of the peripheral zone. A 10-core biopsy scheme incorporating these areas as well as the posterolateral prostate reliably detected cancer in 141 of 147 patients (96%) with total tumor volumes greater than 0.5 cc. CONCLUSIONS: Prostate cancer of significant volume can be present in areas not sampled by standard sextant biopsies. Biopsies of the transition zone, midline peripheral zone and inferior portion of the anterior horn of the peripheral zone should be considered for re-biopsy strategy after negative sextant biopsies. Sampling of these additional areas also can be incorporated in an initial biopsy scheme to increase overall initial rates of detection of prostate cancer. PMID- 9366338 TI - Prognostic implications of a positive apical margin in radical prostatectomy specimens. AB - PURPOSE: We evaluated the prognostic implication of a positive surgical margin at the prostatic apex to define the risk of failure after radical prostatectomy. MATERIALS AND METHODS: Radical prostatectomy specimens of 590 patients operated on between 1990 and 1994 were reviewed by 2 uropathologists (D. G. and W. S.) to determine the percentage of patients with a positive margin at the apex in the absence of positive margins, extraprostatic extension or involvement of seminal vesicles and pelvic lymph nodes. In this group of 33 patients, the significance of a positive apex could be determined without the influence of any other stage related prognostic factors. Treatment failure was defined as prostate specific antigen greater than 0.4. All 33 patients have been followed between 3.5 and 65.5 months (median 38.7). RESULTS: Among 590 patients 236 (40%) had disease completely confined to the prostate. A total of 217 patients (37%) had either positive surgical margins (M+) or extraprostatic extension and of these, only 33 (5.5%) had an apical positive margin in an otherwise prostate confined tumor. Of 33 apical positive margin patients only 3 in whom surgery failed had progressively detectable prostate specific antigen 3.5 to 65.5 months after surgery. CONCLUSIONS: A positive surgical margin at the prostatic apex in the absence of positive margins or extraprostatic extension elsewhere does not confer a worse prognosis than organ confined disease. In this study the recurrence rate for patients with positive apical margins was the same as for those with confined disease. PMID- 9366339 TI - More data on prostatic cancer--how valuable are they? PMID- 9366340 TI - Stability of serum total and free prostate specific antigen under varying storage intervals and temperatures. AB - PURPOSE: Measurement of total serum prostate specific antigen (PSA) is widely used as an aid to early detection of prostate cancer. Measurement of the ratio of free-to-total PSA (percentage of free PSA) may help increase specificity of PSA testing. We prospectively studied the effects of varying the storage temperature and interval on total and free PSA levels. MATERIALS AND METHODS: We measured the baseline total and free serum PSA levels in 36 volunteers (mean age 66 years) and then retested aliquots of these serum samples after varying storage intervals (24 hours, 2 weeks and 9 months) at 3 different temperatures (4C, -20C and -70C). Volunteers represented a spectrum of prostatic conditions (PSA levels 2.0 to 4.0 ng./ml., PSA levels greater than 4.0 ng./ml. without cancer and PSA levels greater than 2.0 ng./ml. with prostate cancer). We used repeated measures analysis of variance to test for changes in total and free PSA levels as a function of time and temperature. We also evaluated the impact of storage at different temperatures and times on the percentage of free PSA. RESULTS: Across groups total and free serum PSA decreased from the baseline level differentially as a function of longer storage interval and higher temperature (p <0.05). No significant difference was found for change in total PSA at 24 hours, 2 weeks or 9 months for storage temperatures of -20C compared with -70C. A significant change from baseline level was found for free PSA when stored in -20C compared with -70C for 2 weeks but the magnitude of the change was modest. CONCLUSIONS: For storage intervals up to 9 months total PSA is more stable than free PSA under temperature conditions ranging from 4C to -70C. This differential stability has important implications for the clinical evaluation of percentage of free PSA to distinguish between benign and malignant diseases of the prostate. PMID- 9366341 TI - Prostatic volume and ratio of free-to-total prostate specific antigen in patients with prostatic cancer or benign prostatic hyperplasia. AB - PURPOSE: We correlated prostatic volume with the ratio of free-to-total prostate specific antigen (PSA) in serum from patients with prostatic cancer or benign prostatic hyperplasia (BPH) to evaluate how prostatic volume influences the ratio. MATERIALS AND METHODS: We evaluated sera from 395 patients (mean age 65 years, range 45 to 88) with prostate cancer (239) or BPH (156) for total PSA, free PSA and ratio of free-to-total PSA. For detection of total and free PSA we used an Immulite free and total PSA assay. Prostatic volume was determined with transrectal ultrasonography. Prostatic volume in BPH and prostate cancer patients was divided into 10 ml. groups, and mean ratio of free-to-total PSA was calculated for each volume group and both diseases. For statistical analysis Mann Whitney U and Kruskal-Wallis tests were performed in addition to calculation of sensitivity and specificity, and receiver operator curves for prostates 60 ml. or less and greater than 60 ml. RESULTS: For BPH patients the mean ratio of free-to total PSA was 14.64 to 25.14% without a close relation to prostatic volume. In prostate cancer patients a proportional increase from 8.45 to 19.37% in the ratio of free-to-total PSA with volume was found. Mann-Whitney U analysis revealed significant differences in prostate cancer versus BPH only in patients with prostates of 60 ml. or smaller (p = 0.0008 to 0.029). No significant differences were seen when prostate cancer and BPH patients with prostates larger than 60 ml. were compared (p = 0.082 to 0.868). Kruskal-Wallis test confirmed independence of the ratio of free-to-total PSA from prostatic volume in BPH patients (p = 0.285) but dependence in prostate cancer patients (p <0.0001). Sensitivity was higher in patients with prostates 60 ml. or smaller (86.72%) than in patients with prostates larger than 60 ml. (66%), and specificity was lower at 45.78 and 56.16%, respectively. CONCLUSIONS: We have shown that the ratio of free-to-total PSA is influenced by prostatic volume in patients with prostate cancer. The ratio of free-to-total PSA provides useful information for differentiate BPH from prostate cancer in patients with small prostates but it is less useful in patients with larger prostates, probably because of the larger proportion of benign hypertrophic tissue. PMID- 9366342 TI - Prostate specific antigen adjusted for the transition zone volume as an indicator of prostate cancer. AB - PURPOSE: We compared prostate specific antigen (PSA) adjusted for the transition zone volume with PSA and PSA density with regard to value in diagnosing prostate cancer in men with intermediate PSA levels of 4.1 to 10.0 ng./ml. in a community based urology practice. MATERIALS AND METHODS: Between October 1994 and May 1996, PSA transition zone was obtained from 92 of 94 men who underwent systematic sextant biopsies and had a PSA value between 4.1 and 10.0 ng./ml. PSA transition zone, calculated by dividing the PSA value by the volume of the transition zone of the prostate, was compared with PSA and PSA density via the receiver operating characteristic (ROC) curves. RESULTS: Of the 92 men 12 (13.0%) had prostate cancer. ROC curve analysis demonstrated that PSA transition zone and PSA density predicted the biopsy outcome significantly better than PSA (p <0.05 and p <0.01, respectively). In a subset of 59 men with normal digital rectal examination PSA transition zone predicted the biopsy outcome better than PSA density, although without significant difference. With a cutoff value of 0.3 PSA transition zone had a sensitivity of 75% and a specificity of 54%. CONCLUSIONS: PSA transition zone is more specific than PSA in distinguishing benign from malignant disease in men with intermediate PSA levels of 4.1 to 10.0 ng./ml., especially in those with normal digital rectal examination. Further study is necessary to discuss whether PSA transition zone is superior to PSA density. PMID- 9366343 TI - Familial prostate cancer: a different disease? AB - PURPOSE: We analyzed the outcome after radical prostatectomy of patients with familial prostate cancer versus patients with sporadic prostate cancer. MATERIALS AND METHODS: The study included 720 patients with prostate carcinoma who were treated with prostatectomy between 1987 and 1996. Patients were excluded from the study if they had received adjuvant or neoadjuvant treatment, or had no available pretreatment prostatic specific antigen (PSA) level, no available biopsy Gleason score, incomplete pathological information or no available followup PSA levels. The analysis was performed on 529 cases. Patients were considered to have a positive family history for prostate cancer when the index patient confirmed the diagnosis of prostate cancer in a first degree relative (brother or father). The outcomes of interest were biochemical relapse-free survival, local failure and distant metastases. Proportional hazards were used to analyze the effect of family history and confounding variables (that is age, stage, biopsy Gleason score, initial PSA levels, surgical specimen Gleason score, extracapsular extension, lymph node metastasis, seminal vesicle invasion and surgical margin involvement) on treatment outcome. RESULTS: Median followup was 30 months. Of all cases 12% had a positive family history. Younger age was the only factor associated with positive family history, with 18% of patients younger than 65 years having a positive family history versus 6% of older patients (chi-square p <0.001). The 5-year biochemical relapse-free survival rate for the entire group was 64%. The 5-year biochemical relapse-free survival rates for patients with negative family history versus positive history were 66% and 46%, respectively (p = 0.001). A multivariate time-to-failure analysis using the proportional hazards model was performed based on family history, age (less than 65 versus 65 to 69 versus 70 or greater, initial PSA (10 or less versus greater than 10), biopsy Gleason score (6 or less versus 7 or greater), clinical T stage (T1-T2A versus T2B-C), prostatectomy specimen Gleason score (6 or less versus 7 or greater), extracapsular extension, seminal vesicle involvement, surgical margin involvement and lymph node involvement. After adjusting for the potential confounding factors, positive family history remained strongly associated with biochemical failure. The clinical failure rate for the entire group was 14%. The 5-year local failure rate was 7%, with positive surgical margins being the only independent predictor of local failure. The 5-year distant metastasis rate was 8%, with family history and initial PSA levels being independent predictors of distant relapse. CONCLUSIONS: Our study suggests that patients with a familial prostate cancer have a higher likelihood of biochemical failure after radical prostatectomy than patients with sporadic cancer. This effect is independent of pretreatment or pathological factors. Our results suggest that the higher failure rates associated with familial prostate cancer are mainly secondary to higher distant relapse rates, and that familial prostate cancer may be more biologically aggressive than sporadic cancers. PMID- 9366344 TI - Extraperitoneal endoscopic pelvic lymph node dissection: a review of 125 patients. AB - PURPOSE: We evaluated the efficacy of a totally extraperitoneal approach to endoscopic pelvic lymph node dissection. MATERIALS AND METHODS: Extraperitoneal endoscopic pelvic lymphadenectomy was performed in 125 patients with clinically localized prostate cancer. All patients were candidates for brachytherapy, cryotherapy or radical perineal prostatectomy. The first 65 patients underwent lymphadenectomy regardless of local clinical stage, prostate specific antigen (PSA) or tumor grade. The last 60 patients met 2 of 3 selection criteria, consisting of clinical local stage T2b or greater, prostate specific antigen greater than 20 and Gleason score 7 or higher. Patients were evaluated for morbidity and mortality, nodal yield, operative time, conversion rate to transperitoneal laparoscopic or open lymphadenectomy and hospital stay. RESULTS: Mean operative time was 104 minutes, mean length of stay was 2.1 days and mean nodal yield was 10.2. Of the patients 19.2% had positive nodes, and positive nodal yield increased to 32.9% when selection criteria were used. Of the cases 4% were converted to a transabdominal laparoscopic approach and 2.4% to open lymphadenectomy. Symptomatic lymphoceles required percutaneous drainage in 2.4% of the patients. One patient died of massive pulmonary embolism. CONCLUSIONS: This study demonstrates that the extraperitoneal endoscopic pelvic lymph node dissection is an effective and relatively safe method of surgically staging prostate cancer. It compares favorably to other methods of surgical staging. PMID- 9366345 TI - Cryosurgical ablation of prostate cancer: patterns of cancer recurrence. AB - PURPOSE: We determined the rate of biochemical and biopsy failure in relation to the prostate specific antigen (PSA) nadir, the effect of neoadjuvant androgen blockade and the pattern of residual tumor after cryosurgical ablation of prostate cancer. MATERIALS AND METHODS: From July 1993 to April 1996, 134 patients underwent 147 cryosurgical ablation procedures. Of those patients, 110 had adequate followup and did not receive post-treatment androgen deprivation. Followup included PSA determination at 3, 6 and 12 months, and every 6 months thereafter. Biopsies were performed at 6 months or with biochemical failure defined as PSA nadir 0.5 ng./ml. or greater or subsequent biochemical failure (PSA increase 0.2 ng./ml. or greater). Biochemical and biopsy failures were correlated with PSA nadir values following cryosurgery (less than 0.1 ng./ml., 0.1 to 0.4 and or greater 0.5). A total of 68 patients had careful ultrasound guided mapping biopsy preoperatively and postoperatively to define the sites of disease. The likelihood of residual disease was correlated with the initial site(s) of the cancer in an attempt to identify if areas of the prostate and/or seminal vesicles were more likely to be sites of treatment failure. RESULTS: At a mean followup of 17.6 months biochemical failure (subsequent rise in PSA 0.2 ng./ml. or greater) was lowest in those who achieved PSA nadirs less than 0.1 ng./ml. (21%) but it was noted in 48% of patients with nadirs between 0.1 and 0.4 ng./ml. Those patients with PSA nadirs 0.5 or greater had either immediate local failure (46%), subsequent local or biochemical failures (43%) or extremely high PSA nadirs (greater than 30 ng./ml.) necessitating hormonal therapy (11%). Biopsy failure was lowest in those with nadirs less than 0.1 ng./ml. (7%) and those with nadirs 0.1 to 0.4 ng./ml. (22%). In contrast, 60% of the patients with nadir values 0.5 ng./ml. or greater had biopsy failure. Biochemical and biopsy failure tended to occur within the first 18 months after treatment. Neoadjuvant androgen blockade appeared to reduce subsequent biochemical failure in patients with stages T1 and T2 cancers (11% versus 50% in those without androgen deprivation) but not in those with T3 and T4 cancers. Recurrence was more common in cancers at the apex (9.5%) and seminal vesicles (44%), in contrast to those located in the mid gland (4%) and base (0%). CONCLUSIONS: A PSA nadir of 0.4 ng./ml. or less should be achieved following cryotherapy. Higher values are associated with a significant risk of continued PSA elevation and a high likelihood of residual disease detected on prostatic biopsy. Local failure tends to occur at the apex and seminal vesicles. Neoadjuvant androgen blockade reduces the risk of biochemical failure in patients with stages T1 and T2 cancers. PMID- 9366346 TI - Late venous thromboembolic disease after radical prostatectomy: effect of risk factors, warfarin and early discharge. AB - PURPOSE: We determined the incidence of late venous thromboembolic disease after radical prostatectomy, and the influence of risk factors, length of hospital stay and warfarin anticoagulation. MATERIALS AND METHODS: Patients undergoing radical prostatectomy received routine deep vein thrombosis prophylaxis that consisted of intermittent pneumatic compression stockings, early ambulation and warfarin administration during hospitalization with the goal of achieving a prothrombin time international normalized ratio of 1.5 or greater. When patients returned to the hospital for postoperative evaluation, venous duplex ultrasonography of the lower extremities was done. All patients were contacted at 2 months to ensure that they did not suffer a clinical thromboembolic event. RESULTS: One of 158 patients consenting to the study had a symptomatic thromboembolic event for a clinical incidence of 0.6% (95% confidence interval 0.0 to 3.5). Duplex ultrasonography was performed 21.4 +/- 7.8 days postoperatively and 3 of the 106 patients who completed the study had a positive ultrasound for an incidence of 2.8% (95% confidence interval 0.6 to 8.1). None of these patients suffered a symptomatic thromboembolic event. Age, body mass index, length of hospital stay, operative time, estimated blood loss, prostate specific antigen and Gleason score were evaluated for a statistical relationship with thromboembolic events. Only higher body mass index and length of hospitalization approached statistical significance. CONCLUSIONS: Late deep vein thrombosis can occur after radical retropubic prostatectomy. Shorter prophylaxis period, secondary to shorter periods of hospitalization, did not increase the risk of thromboembolic events. The combination of intermittent pneumatic compression stockings and warfarin anticoagulation may be contributing to the relatively low deep vein thrombosis rate in our study compared to previous studies. PMID- 9366347 TI - Teleradiology in urology: comparison of digital image quality with original radiographic films to detect urinary calculi. AB - PURPOSE: Teleradiology systems are now being evaluated as a mechanism to provide rapid, accurate and cost-effective diagnostic radiographs to off-site physicians. Little data are available on the role and safety of teleradiology in urology. To address these issues a personal computer based system was developed to assess the diagnostic accuracy and ease of use of transmitted digital images when evaluating for urinary calculi. MATERIALS AND METHODS: A total of 100 plain abdominal scout films from excretory urograms performed during acute urological referrals was digitized on a laser scanner. The 10 megabyte files were transferred over public telephone lines and written to compact disks. The images were viewed on a 1280 x 1640 resolution monitor using "Imager-3D" software run on a 133 MHz. pentium personal computer with 32 megabytes of random access memory. Two faculty urologists and 2 urology fellows each looked at 50 original radiographs and 50 digital images. Diagnostic interpretations of the presence and location of calculi were recorded, and confidence in the diagnosis, assessment of image quality and diagnostic difficulty were scored using a numerical scale. RESULTS: The accuracy for all readers was 86.5% for plain radiographs and 81.5% for digital images (p >0.2). There was no statistical difference between faculty and fellows. Diagnostic accuracy did not differ between plain films and screen images when the results were assessed with respect to image quality, diagnostic difficulty or the reader confidence in the diagnosis (p >0.1). Compared to plain films, more screen images were classified as lower image quality (60 versus 40%) and the diagnostic confidence was lower (low and medium grade 50 versus 35%), although this did not interfere with diagnostic accuracy. CONCLUSIONS: These data imply that a high quality affordable teleradiology system is effective and accurate compared to plain films for assessing urinary calculi. PMID- 9366348 TI - Geriatric urolithiasis. AB - PURPOSE: We define the differences between geriatric patients with urinary stone disease compared to a younger cohort. MATERIALS AND METHODS: A data base, including serum biochemical profiles, 24-hour urinalyses and standardized questionnaires, was retrospectively evaluated from more than 6,000 consecutive patients with urinary stone disease. RESULTS: Geriatric stone formers comprised 12% (721) of all stone patients. Two-thirds of these elderly patients had aberrant urinary values and 29% had isolated hypocitraturia compared to 17% in the younger group. Of geriatric stone forming patients 76% had recurrent urinary stones (mean 3.5 stone episodes), which was similar to the younger comparable group (77%, mean 3.3 stone episodes). The severity of urinary stone disease was similar between the 2 groups based on the need for urological intervention. Geriatric stone patients, in general, experienced the first stone episode later in life (after age 50 years) compared with younger patients. Elderly patients had an increased incidence of uric acid stones, but had a similar incidence of struvite calculi. Geriatric stone patients underwent parathyroid surgery more frequently (2.7 versus 0.7%). Geriatric stone forming patients rarely had renal failure. CONCLUSIONS: The incidence, recurrence and severity of recurrent urinary stone disease were similar between geriatric and younger stone forming patients. Geriatric stone patients had an increased incidence of isolated hypocitraturia, uric acid calculi and previous parathyroidectomy. The geriatric stone population is not merely an extension of younger stone forming patients presenting at an older age. Rather, geriatric patients commonly experience the first symptomatic stone episode later in life. PMID- 9366349 TI - A simplified method of ureteral stent removal using waterless rigid urethroscopy. PMID- 9366350 TI - Hazards of laparoscopic adrenalectomy in patients with adrenal malignancy. PMID- 9366351 TI - Management of indinavir associated nephrolithiasis. PMID- 9366352 TI - Polycystic horseshoe kidney. PMID- 9366353 TI - Mucormycosis presenting as a renal mass in a patient with the human immunodeficiency virus. PMID- 9366354 TI - Retroperitoneal mucinous cystadenoma presenting as a renal cyst. PMID- 9366355 TI - Intrahepatic tumor thrombectomy through an abdominal diaphragmatic approach. PMID- 9366356 TI - Vaginal ectopic ureter with Gartner's duct cyst. PMID- 9366357 TI - Orthotopic neobladder in a woman after kidney transplantation. PMID- 9366358 TI - Complete phalloplasty with a prelaminated osteocutaneous fibula flap. PMID- 9366359 TI - Vasodilator induced arteriovenous shunt during penile arteriography for impotence. PMID- 9366360 TI - Induction of spermatogenesis and pregnancy after adult orchiopexy. PMID- 9366361 TI - Vasovenous fistula after vasectomy. PMID- 9366362 TI - Splenosis presenting as a mass on digital rectal examination. PMID- 9366364 TI - The perceived need for academic urology positions in the United States. AB - PURPOSE: The goal of this report is to provide information regarding the number of potential academic positions available for newly trained urologists in the United States. MATERIALS AND METHODS: In August 1995 and November 1996, a 5 question survey was mailed to 115 chairs or division heads in the United States, requesting total of faculty hires anticipated during the next 5 years, prerequisite fellowship training, areas of subspecialty expertise, American Urological Association section and estimated protected time for research. RESULTS: Response rate was 86% (98 programs). In 1995 there were 203 anticipated jobs, including 45 positions for oncology, 40 neurourology/female urology, 37 calculus/endourology, 26 general/urology office, 25 infertility/impotence, 23 pediatric, and 7 transplant urology. Of the positions 51% will require at least a clinical fellowship, and 83% of these individuals will be offered 10 to 25% protected time for research. By 1997 there were only 20 less predicted positions and only 11 departments anticipated less hires than 1 year earlier. CONCLUSIONS: The number of near-term urology positions is encouraging for individuals interested in academic urology. Optimistic predictions probably reflect unique service, research and teaching needs for academic programs rather than merely manpower requirements based on projected managed care models. Anticipated faculty positions appear to exceed overall projections pertaining to the need for urologists based solely on patient population demographics. PMID- 9366363 TI - Suramin keratosis: a unique skin eruption in a patient receiving suramin for metastatic prostate cancer. PMID- 9366365 TI - Spontaneous retroperitoneal hemorrhage from a giant adrenal myelolipoma. PMID- 9366366 TI - International conference on Peyronie's disease: advances in basic and clinical research. PMID- 9366367 TI - Vasectomy reversal for treatment of the post-vasectomy pain syndrome. PMID- 9366368 TI - Easy visualization of the membranous urethral stump in radical prostatectomy. PMID- 9366369 TI - Easy visualization of the membranous urethral stump in radical prostatectomy. PMID- 9366370 TI - Wilms tumor and multicystic dysplastic kidney disease. AB - PURPOSE: There is ongoing controversy concerning the management of multicystic dysplastic kidney disease, particularly with regard to the potential for malignant transformation. Our report fuels the debate by adding the 2 youngest patients in whom malignancy was present from birth or developed subsequently. MATERIALS AND METHODS: Two well documented cases of malignancy associated with multicystic dysplastic kidney disease are presented in 2 female infants (5 and 3 months old). The 5-month-old female infant was followed for multicystic dysplastic kidney disease and had no evidence of tumor either antenatally or at birth. The 3-month-old presented with hypertension and interventricular septal defect. A renal tumor was present on initial ultrasound. RESULTS: Even though malignant degeneration is rare in multicystic dysplastic kidney disease, 9 cases have been reported in the literature so far. Of these cases 3 were Wilms tumor, 5 were renal cell carcinomas and 1 mesothelioma. CONCLUSIONS: Our 2 cases lend support to the surgical management of multicystic dysplastic kidney disease, particularly as nephrectomy can now be performed in a day surgery setting with minimal morbidity. Only the risks of coexisting malignancy and possible malignant degeneration transformation are specifically addressed in this article. Other complications of multicystic dysplastic kidney disease such as hypertension, infection, abdominal pain, hematuria and persistent dysplastic renal tissue despite ultrasonographic resolution of multicystic dysplastic kidney disease are additional risk factors to be considered. A recommendation for nephrectomy in all cases of multicystic dysplastic kidney disease cannot be based only on these 2 cases. Several other factors must be weighed before making that decision. PMID- 9366371 TI - Estimating normal bladder capacity in children. AB - PURPOSE: An accurate estimation of normal bladder capacity can be helpful in evaluating the patient with genitourinary disease and in interpreting urodynamic data. Prior studies have provided initial estimates. We propose 2 new equations that are practical, easy to use and more accurate than those previously published. MATERIALS AND METHODS: We retrospectively reviewed the records of more than 5,000 children undergoing radionuclide cystography at our institution. Radionuclide cystography was conducted by instilling (99m)technetium pertechnetate via gravity drip in awake children. Bladder capacity was believed to be achieved when rate of inflow diminished to a minimal rate, initiation of voiding occurred or significant discomfort was indicated. Patients with vesicoureteral reflux, infravesical obstruction, urinary tract infection, dysfunctional voiding or other lower urinary tract pathology were excluded from the study. Linear and nonlinear regression modeling established the relationship between age and bladder capacity. RESULTS: A total of 2,066 children (598 boys and 1,468 girls) had normal radionuclide cystography and were included in the analysis. Analysis of variance demonstrated that increasing age was strongly predictive of bladder capacity (p <0.0001). Because a nonlinear model was the most accurate formula for all ages (4.5 x age(0.40) = capacity [ounces]), 2 practical linear equations were determined: 2 x age (years) + 2 = capacity (ounces) for children less than 2 years old, and age (years) divided by 2 + 6 = capacity (ounces) for those 2 years old or older. Although girls had larger capacities than boys, the rate of increase was not significantly different between them. CONCLUSIONS: The relationship between normal bladder capacity and age in children follows a nonlinear curve. This nonlinear relationship can be approximated by 2 practical linear formulas that are easy to remember and are derived from a larger population than any prior study. These formulas provided accurate estimations of bladder capacity when prospectively applied to normal patients. PMID- 9366372 TI - Primary Ewing's sarcoma of the bladder associated with an elevated antinuclear antibody titer. PMID- 9366373 TI - Desmopressin for nocturnal incontinence in the spina bifida population. AB - PURPOSE: We report our experience with the use of desmopressin in the spina bifida population that is dry during the day but wet at night. MATERIALS AND METHODS: From 1994 to 1996, 18 patients with myelodysplasia were treated with desmopressin for persistent nocturnal enuresis. Initial dose was 40 mcg. before bedtime, decreased by intervals of 10 mcg. every 3 weeks. Patients were kept on the minimum dose required to keep them dry. We reviewed morning catheterized volumes, side effects and dosages needed to stay dry, and compared augmented patients with nonaugmented patients. RESULTS: Of 18 patients 14 (78%) reported marked improvement in nocturnal enuresis. Of 6 augmented patients 5 (83%) are dry compared to 9 of 12 nonaugmented patients (75%). There were no adverse side effects from the use of desmopressin. Average dose to stay dry was 20 mcg. for augmented and 30 mcg. for nonaugmented patients. Of the 4 patients who had persistent nocturnal incontinence despite desmopressin 3 (75%) became dry with a single catheterization in the middle of the night. CONCLUSIONS: Desmopressin is successful in treating nocturnal enuresis in the spina bifida patient with diurnal continence. PMID- 9366374 TI - Surgical repair of urethral circumcision injuries. AB - PURPOSE: The 2 types of urethral injury that can occur during circumcision are urethrocutaneous fistula and urethral distortion secondary to partial glans amputation. We report the surgical repair of these rare injuries. MATERIALS AND METHODS: In 8 patients urethrocutaneous fistulas located on the distal penile shaft or at the coronal margin were managed by splitting the glans and using a Mathieu style skin flap in 4 or vascularized penile skin flap in 4 to bridge the urethral defect. Three patients underwent repair of a hypospadiac deviated urethra secondary to partial glans amputation by 1 cm. of urethral mobilization and repositioning the meatus into a terminal position within the remaining glans tissue. RESULTS: The 8 patients with urethrocutaneous fistulas voided via a terminal meatus without fistula recurrence at a mean followup of 3.2 years (range 1 to 6). The 3 patients with partial glans amputation and urethral deviation repaired by short urethral advancement had functionally acceptable results, defined as a normal urinary stream, although 1 required meatal dilation postoperatively. CONCLUSIONS: The 2 types of urethral injuries that can occur during circumcision are a subcoronal urethrocutaneous fistula and scarred abnormal urethra from partial glans amputation. The urethrocutaneous fistula can be successfully repaired by splitting the glans and forming a neourethra from a vascularized pedicle flap of penile skin. The abnormal urethra after partial glans amputation is more difficult to repair but repositioning the urethra in a more cosmetic location has restored function. PMID- 9366375 TI - Perineal lipoblastoma in a neonate. PMID- 9366376 TI - Combined analysis with Bcl-2 and P53 immunostaining predicts poorer prognosis in prostatic carcinoma. AB - PURPOSE: The objective of the current study is to investigate the relationship between bcl-2 and p53 expression and prognosis in prostatic carcinoma. MATERIALS AND METHODS: One hundred and forty-six needle core biopsy specimens obtained before any treatment were used for immunohistochemical detection of bcl-2 and p53 positivity. The relationship between these proteins was assessed by serial sections. Associations with Gleason score, clinical stage and patient survival were studied. Additionally, multivariate analysis by Cox proportional hazard model was used to determine the prognostic significance of these proteins. RESULTS: Bcl-2 positivity was found in 20% and p53 in 27% of 146 prostatic carcinomas. Both bcl-2 and p53 positivity were found only in 5%. They were expressed almost reciprocally in the tumors. P53 positivity correlated with high Gleason grade tumors. Bcl-2 positivity correlated with high T stage. Both bcl-2 and p53 positivity correlated with poor survival and short progression-free period. Multivariate analysis revealed that bcl-2 positivity was an independent prognostic indicator (p = 0.001). CONCLUSIONS: Bcl-2 and p53 were almost independently expressed in prostatic cancer. Both correlated with malignant phenotypes of prostatic cancer. The combined data from this staining further improved the ability to predict the patient prognosis. PMID- 9366377 TI - An animal model of Peyronie's-like condition associated with an increase of transforming growth factor beta mRNA and protein expression. AB - PURPOSE: Transforming growth factor beta (TGF-beta) is involved in numerous vital processes including tissue fibrosis. Our objective was to study the role of TGF beta in the induction of a Peyronie's-like condition and to produce an animal model for the further study of Peyronie's disease. MATERIALS AND METHODS: Twenty four adult male Sprague-Dawley rats were divided into two groups. Different concentrations of cytomodulin, a synthetic heptopeptide with TGF-beta-like activity, were injected into the tunica of each rat from the first group (n = 18). Rats in the second group (n = 6) received saline injections as a control. The tunical tissues were taken after 3 days, 2 weeks, and 6 weeks and were examined using Hart and Trichrome stains. In the same tissue samples, TGF-beta mRNA and protein expression were studied. RESULTS: Histological alterations were observed in 15 out of 18 cytomodulin-injected rats, especially in tissue examined after 6 weeks. The most prominent changes were chronic cellular infiltration, focal and diffuse elastosis, thickening, disorganization and clumping of the collagen bundles. Results from immunoblot revealed remarkable TGF-beta1 protein expression in all the cytomodulin-injected rats only after 2 and 6 weeks. No remarkable TGF-beta2 or TGF-beta3 protein expression was observed. TGF-beta1 mRNA expression in the cytomodulin-injected rats was noticed in rats injected with higher concentrations after 3 days, while it was expressed in all rats after 2 weeks. There was no expression in the control group after either 3 days or 2 weeks. CONCLUSIONS: Cytomodulin can induce Peyronie's-like condition in the rat penis, which may explain the role of TGF-beta in the pathogenesis of Peyronie's disease. PMID- 9366379 TI - Comparison of the uroprotective efficacy of mesna and HBO treatments in cyclophosphamide-induced hemorrhagic cystitis. AB - The aim of this research was to compare the protective effects of mesna, hyperbaric oxygenation (HBO), and their combination in cyclophosphamide-induced hemorrhagic cystitis in guinea pigs. Following one dose of i.p. 21.5 mg./kg. mesna administration 20 minutes before i.p. 68.1 mg./kg. cyclophosphamide, 3 additional doses of mesna were given every three hours. A total of 8 HBO exposures, 5 of which were applied prophylactically before cyclophosphamide, were performed at 2.8 ATA for 90 minutes 2 times a day. Although mesna or HBO provided significant protection for cyclophosphamide-cystitis in animal bladders, there was also significant damage compared with controls. The combination of mesna and HBO, which act through independent mechanisms, resulted in complete protection, since mean histological scores and hematuria levels in this group were not different from controls (p >0.05). Therefore, this combination may be a useful tool in the prophylaxis and treatment of cyclophosphamide-induced hemorrhagic cystitis. PMID- 9366378 TI - Detection of eubacteria in interstitial cystitis by 16S rDNA amplification. AB - OBJECTIVE: To determine what role non-culturable microorganisms play in the etiology of interstitial cystitis (IC). MATERIALS AND METHODS: Thirty patients fulfilling NIH criteria for the diagnosis of interstitial cystitis and sixteen control patients with culture negative urine gave written informed consent and underwent bladder biopsy. Polymerase chain reaction (PCR) using two sets of universal primers for bacterial 16S rDNA was performed on urine from the cystoscope and on a cold cup bladder biopsy specimen. Of the PCR positive bladder biopsies, three patients with interstitial cystitis and three controls were randomly selected and cloned. Ten clones from each were sequenced and putative taxonomic assignments made. RESULTS: 12/26 (46%) IC and 5/12 (42%) control urine specimens and 16/30 (53%) and 9/15 (60%) bladder biopsies were PCR positive, respectively. The bacterial populations in the two patient groups tested appeared to be different based upon analysis of the 16S rRNA sequences. CONCLUSIONS: Both IC and control patients had non-culturable bacteria in their bladders. A random sampling of the two populations revealed that the bacterial populations are different, suggesting a possible link between one or more bacterial species and IC. PMID- 9366380 TI - Effects of the K+ channel opener, ZD6169, on volume and PGE2-stimulated bladder activity in conscious rats. AB - PURPOSE: To investigate the effects of the new K(ATP) channel opener, ZD6169, shown to have an in vivo selectivity for the bladder, on bladder activity in rats. MATERIALS AND METHODS: ZD6169 was given intra-arterially (i.a., 0.1 and 1 mg./kg.) or orally (3 mg./kg.) to conscious Sprague-Dawley rats undergoing continuous cystometry. Investigations were also performed before and after stimulation of bladder activity by intravesical prostaglandin (PG) E2. RESULTS: Intra-arterial ZD6169 increased residual volume, but caused no changes in other cystometric parameters. In rats receiving oral ZD6169, cystometric parameters were compared (every hour up to five hours) to those recorded in rats receiving oral vehicle. No differences were found, except in threshold pressure, which was significantly increased. Intravesical PGE2 20 microM increased micturition and basal pressures, and decreased bladder capacity and micturition volume. ZD6169 1 mg./kg., given i.a., reduced or completely prevented the activity induced by intravesical PGE2. Three hours after orally administered ZD6169 (3 mg./kg.), intravesical PGE2 20 microM had no effect. Three hours after oral administration of vehicle, the effects of PGE2 were attenuated, but still statistically significant. CONCLUSIONS: ZD6169, given i.a. or orally, increased threshold pressure, but had otherwise little effect on volume-induced micturition. However, the drug markedly reduced or prevented PGE2-induced bladder activity when given i.a.; it was also effective when given orally. If ZD6169 has inhibiting effects on bladder contraction in man without any cardiovascular actions, the drug may represent a novel, promising way of treating bladder overactivity. PMID- 9366381 TI - Renal stone risk assessment during Space Shuttle flights. AB - PURPOSE: The metabolic and environmental factors influencing renal stone formation before, during, and after Space Shuttle flights were assessed. We established the contributing roles of dietary factors in relationship to the urinary risk factors associated with renal stone formation. MATERIALS AND METHODS: 24-hr. urine samples were collected prior to, during space flight, and following landing. Urinary and dietary factors associated with renal stone formation were analyzed and the relative urinary supersaturation of calcium oxalate, calcium phosphate (brushite), sodium urate, struvite and uric acid were calculated. RESULTS: Urinary composition changed during flight to favor the crystallization of calcium-forming salts. Factors that contributed to increased potential for stone formation during space flight were significant reductions in urinary pH and increases in urinary calcium. Urinary output and citrate, a potent inhibitor of calcium-containing stones, were slightly reduced during space flight. Dietary intakes were significantly reduced for a number of variables, including fluid, energy, protein, potassium, phosphorus and magnesium. CONCLUSIONS: This is the first in-flight characterization of the renal stone forming potential in astronauts. With the examination of urinary components and nutritional factors, it was possible to determine the factors that contributed to increased risk or protected from risk. In spite of the protective components, the negative contributions to renal stone risk predominated and resulted in a urinary environment that favored the supersaturation of stone-forming salts. Dietary and pharmacologic therapies need to be assessed to minimize the potential for renal stone formation in astronauts during/after space flight. PMID- 9366382 TI - Pharmacological biocompatibility between intravesical preparations of BCG and interferon-alpha 2B. AB - PURPOSE: To determine if BCG and interferon alpha-2B are mutually compatible as mixed intravesical agents for clinical bladder cancer therapy. MATERIALS AND METHODS: Mutual compatibility was assessed by measuring IFN-alpha's effect on BCG metabolic activity, growth rate, and clumping tendency and conversely by observing BCG's effect on IFN-alpha's anti-viral activity. Optical density at 600 nm. (OD600) was used to estimate the number of colony forming units of BCG in suspension during 3 hours measurements of clumping and 8 days measurements of BCG proliferation. BCG viability was evaluated using a substrate marker, MTT, which correlates with BCG density and metabolic activity. The anti-viral activity of IFN-alpha was determined in a cytopathic protection bioassay using the encephalomyocarditis virus/FS-4 cell system. RESULTS: Continuous shaking of reconstituted BCG for 3 hours at 37C resulted in a marginal (11.3%) drop in OD600 which was minimally altered by inclusion of IFN-alpha at 2 million units (MU)/ml. (12.7% drop). Metabolic activity and growth rate of BCG alone or BCG with IFN alpha were essentially identical. IFN-alpha's antiviral activity was not affected by incubation with BCG. CONCLUSIONS: The inclusion of IFN-alpha into the usual BCG formulation for intravesical administration has no apparent effect on BCG's viability or tendency to form clumps in suspension. Similarly, the physical mixing of IFN-alpha with BCG does not impair its biological activity. Thus, both agents are pharmacologically compatible for future clinical studies involving combination intravesical therapy. PMID- 9366384 TI - Controlled, forced collapse of cavitation bubbles for improved stone fragmentation during shock wave lithotripsy. AB - The feasibility of using controlled, forced collapse of cavitation bubbles for improved stone fragmentation during shock wave lithotripsy was demonstrated using microsecond tandem shockwave pulses. High-speed photography revealed that a secondary shock wave, released in less than 500 microseconds (microsec.) following a lithotripter-generated shock wave, can be used to control and force the collapse of cavitation bubbles toward target concretions. This timely enforced shockwave-bubble interaction was found to greatly enhance the cavitational activity near the stone surface, with a resultant up to 43% increment in stone fragmentation. Since most of the cavitation energy is directed and concentrated toward the target stones and fewer shock waves are needed for successful stone comminution, tissue injury associated with this new lithotripsy procedure may also be reduced. This novel concept of shock wave lithotripsy may be used to improve the treatment efficiency and safety of existing clinical lithotripters, as well as in the design of new shock wave lithotripters. PMID- 9366383 TI - Mizoribine improves renal tubulointerstitial fibrosis in unilateral ureteral obstruction (UUO)-treated rat by inhibiting the infiltration of macrophages and the expression of alpha-smooth muscle actin. AB - PURPOSE: Several lines of evidence suggest that the infiltration of macrophages and the expression of alpha-smooth muscle actin in myofibroblasts play important roles in the pathogenesis of tubulointerstitial fibrosis. However, the temporal sequence of these pathological changes or the dynamics in the expression of this cytoskeletal molecule in the process of tubulointerstitial fibrosis have not been precisely documented. MATERIALS AND METHODS: We investigated the infiltration of macrophages and the expression of alpha-smooth muscle actin in interstitial fibrosis caused by a unilateral ureteral obstruction (UUO) experimental model. RESULTS: The result showed that the macrophages were immobilized at the interstitium and alpha-smooth muscle actin was up-regulated in myofibroblasts of both cortex and medulla at day 3 when interstitial volume start to increase significantly. The highest expression of alpha-smooth muscle actin was detected at day 5 and the most intense infiltration of macrophages was noted at day 14 while the interstitial volume in renal cortex and medulla continued to increase until day 28. Furthermore, we investigated the effect of mizoribine, an immunosuppressive agent, on the interstitial fibrosis induced by UUO, demonstrating that mizoribine, but not prednisolone, significantly improves the tubulointerstitial fibrosis by suppressing the macrophage infiltration and the expression of alpha-smooth muscle actin. CONCLUSIONS: We discuss the pathological roles of macrophages and alpha-smooth muscle actin in tubulointerstitial fibrosis induced by UUO treatment. We also emphasize the pharmacological basis and clinical relevance of mizoribine in the treatment of interstitial fibrosis caused by obstructive nephropathy. PMID- 9366385 TI - Virulence characteristics and DNA fingerprints of Escherichia coli isolated from women with acute uncomplicated pyelonephritis. AB - PURPOSE: Previous studies indicated that acute pyelonephritis in infants is initiated by the dominance of uropathogenic strains in fecal flora. Such pathogenic evidence, however, is still lacking for adult women. In this study, the validity of a fecal-perineal-urethral hypothesis in acute uncomplicated pyelonephritis of adult women was assessed at a genetic level. MATERIALS AND METHODS: A total of 1,200 Escherichia coli isolates from the urine and rectal swab of 12 adult women with acute uncomplicated pyelonephritis were examined. The clonality of the urinary and fecal isolates was evaluated by genotyping of 6 urovirulence determinants and pulsed-field gel electrophoresis. Furthermore, urovirulence genotypes were examined in E. coli isolates from the rectal swab of 30 normal healthy women (mean 26.7 isolates per person). RESULTS: The E. coli strains causing pyelonephritis were present in the rectal swab in 10 of 12 patients and were a predominant fecal clone in 9 cases. Also, P-fimbriated strains dominated in the fecal flora in 10 of 30 normal healthy women. CONCLUSIONS: The clonal identity of the urinary and fecal strains in acute pyelonephritis clearly supports the fecal-perineal-urethral hypothesis. PMID- 9366386 TI - American Association of Immunologists Presidential Address: doing it together: a perspective on the process of experimental science. AB - We are witnessing profound changes in how experimental science is done and the rate at which scientists are discovering nature's secrets. While we are experiencing this phenomenal change, we are also at risk, because along with these changes comes the potential for altering the values by which we do science. I share with everyone in our field an abiding concern that scientists of the next generation embrace the values that have guided my generation and the generations of scientists that have preceded me. Because relationships in science are key to passing on these values, I have focused the first part of this address on the importance that relationships have played in guiding my scientific process. In the second part; Looking Toward Our Future, I discuss how the mentoring relationship can serve as an antidote to pressures that threaten our scientific values. PMID- 9366387 TI - New evidence for two MHC class II-restricted antigen presentation pathways by overexpression of a small G protein. AB - Exogenous Ags may be presented by MHC class II molecules through two distinct pathways distinguished by their sensitivity to drugs that inhibit the protein synthesis. Using this approach, we previously showed that the subunits Ig-alpha and Ig-beta, associated to B cell Ag receptor, targeted Ags either to newly synthesized or to preexisting pools of MHC class II molecules, respectively. To further characterize these two Ag presentation pathways, we altered the intra Golgi transport of newly synthesized MHC class II by stably overexpressing, in B cells, mutants of a small G protein involved in the intra-Golgi transport, Rab6. Overexpression of GTP-bound rab6 (Q72L) mutant proteins reduced the cell surface arrival of MHC class II molecules and consequently slowed down Ag presentation dependent upon newly synthesized class II molecules. In contrast, this mutant had no effect on Ag presentation dependent upon preexisting pools of class II molecules, and the overexpression of an inactive GDP-bound form of rab6 (T27N) did not affect any Ag presentation pathway. MHC class II-restricted Ag presentation pathways can therefore be distinguished by their sensitivity to the overexpression of proteins modifying the intracellular transport of newly synthesized class II molecules. PMID- 9366389 TI - Antigen recognition and allogeneic tumor rejection in CD8+ TCR transgenic/RAG(-/ ) mice. AB - Three sources of help for the development of a CD8+ CTL response have been described: the CD4+ direct and indirect pathways and the CD8+ direct pathway. In an effort to understand the minimal requirements for the development of a CTL response in vivo, we have bred mice transgenic for the 2C TCR onto a RAG(-/-) background. The 2C T cells in this animal are exclusively CD8+ CTLs of a single specificity, and they exhibit altered thymic maturation compared with that of T cells from 2C TCR/RAG(+/+) mice. T cells from 2C TCR/RAG(-/-) mice can be activated to a high level in vivo by administration of a self-MHC-restricted antigenic peptide. The 2C TCR/RAG(-/-) mice are able to reject B7-negative allogeneic tumors bearing the appropriate peptide/MHC ligand p2C/Ld. These mice fail to reject syngeneic tumors, and their RAG(-/-) littermates lacking 2C T cells uniformly succumb to both allogeneic and syngeneic tumors. Moreover, blockade of B7 costimulatory molecules fails to prevent tumor rejection in the 2C TCR/RAG(-/-) mice, suggesting that allorejection is occurring independently of B7 mediated costimulation as well as in the absence of CD4+ T cells. CTLs isolated from the site of the tumor during the period of rejection express the activation marker CD25 and are able to mediate ex vivo cytolysis of tumor cells bearing the appropriate Ag. These results suggest that in this TCR transgenic model with a very high precursor frequency, CTL development can occur in the absence of B7:CD28 costimulation and without CD4+ help. PMID- 9366388 TI - Induction of procoagulant function in porcine endothelial cells by human natural killer cells. AB - NK cells may mediate effector functions other than target cell cytotoxicity. To explore such noncytotoxic effector mechanisms, we tested whether human PBL and purified NK (CD56+) cells might induce expression of tissue factor by cultured porcine aortic endothelial cells. Tissue factor is the major coagulation factor that binds to factor VIIa and initiates coagulation. The addition of freshly isolated NK cells but not T cells to endothelial cells resulted in the induction of tissue factor activity. NK-depleted (CD56-) effector cells did not induce tissue factor activity; however, the combination of CD56+ cells and NK-depleted cells induced tissue factor activity to the same extent as unseparated cells. PBL induced tissue factor mRNA in porcine endothelial cells and NK depletion resulted in a significant decrease of the induction. Induction of tissue factor activity in porcine endothelial cells by human NK cells required direct cell-to-cell contact, as transfer of supernatants from NK-endothelial cell cultures to secondary cultures did not induce tissue factor activity, and anti-LFA-1alpha Abs inhibited the induction of tissue factor activity. Induction of tissue factor activity in endothelial cells by NK cells may represent one of a variety of ways in which NK cells mediate noncytotoxic effects. PMID- 9366390 TI - Transcriptional regulation of the junB gene in B lymphocytes: role of protein kinase A and a membrane Ig-regulated protein phosphatase. AB - We have examined herein whether membrane Ig (mIg) stimulates junB transcription through a protein kinase A (PKA)-dependent or PKA-independent pathway. PKA phosphotransferase activity was not increased following mIg cross-linking of Bal17 B cells. However, junB transcriptional activation was dependent upon PKA activity, as evidenced by inhibition of goat anti-mouse IgM-stimulated junB promoter-chloramphenicol acetyltransferase reporter gene activity in transfected Bal17 B cells treated with the PKA inhibitor H-89. mIg-stimulated junB promoter chloramphenicol acetyltransferase activity was also blocked in B cells expressing a specific PKA inhibitor peptide, whereas in vivo expression of an inactive PKA inhibitor peptide variant was not inhibitory. Expression of a mutant cAMP response element binding protein (CREB) containing an inactivated kinase A phosphoacceptor site at Ser133 reduced mIg-stimulated junB transcription. Okadaic acid increased CREB1 phosphorylation at Ser133 and junB transcriptional activation, suggesting the action of protein phosphatase-1 (PP-1) or -2A (PP-2A). Extracts from unstimulated B cells exhibited phosphatase activity against an in vitro PKA-phosphorylated peptide containing the Ser133 phosphoacceptor site. The involvement of a phosphatase activity in regulating mIg-stimulated junB transcription is supported by our finding that extracts from goat anti-mouse IgM stimulated B cells exhibited a significantly reduced level of Ser133 phosphatase activity. Hence, the level of CREB1 phosphorylation is governed by the balance between PKA and phosphatase activities. junB transcriptional activation results in part from mIg signals that negatively regulate a CREB1-targeted PP-1 or PP-2A activity. PMID- 9366392 TI - Natural processing sites for human cathepsin E and cathepsin D in tetanus toxin: implications for T cell epitope generation. AB - Cathepsin E is an aspartic proteinase that has been implicated frequently in Ag processing for presentation on class II MHC molecules, but no information exists on its cleavage specificity within Ags in relation to known T cell epitopes. We have analyzed the processing by cathepsin E of a large C-terminal domain of tetanus toxin (residues 872-1315), and we have compared the processing products with those liberated by cathepsin D, a related aspartic proteinase also thought to be involved in class II MHC-restricted Ag processing. Processing products were analyzed by N-terminal Edman degradation and mass spectrometry following reverse phase HPLC separation of peptides. A total of 28 cleavage sites was identified, 11 of which were recognized by both cathepsins E and D. Most, although not all, sites were between pairs of hydrophobic residues and were located within the 200 amino-acid C terminal region known to contain several human T cell epitopes. Previously described T cell epitopes, for example, between residues 1273 and 1284, were flanked by cathepsin E and D cleavage sites. These data are consistent with an important role for cathepsins E and/or D in Ag processing in the human immune system. PMID- 9366391 TI - IL-4 prevents insulitis and insulin-dependent diabetes mellitus in nonobese diabetic mice by potentiation of regulatory T helper-2 cell function. AB - Beginning at the time of insulitis, nonobese diabetic (NOD) mice demonstrate a thymocyte and peripheral T cell proliferative hyporesponsiveness induced by TCR cross-linking, which is associated with reduced IL-2 and IL-4 secretion. We previously reported that NOD CD4+ T cell hyporesponsiveness is reversed completely in vitro by exogenous IL-4, and that administration of IL-4 to NOD mice prevents the onset of insulin-dependent diabetes mellitus (IDDM). This result suggested that T cell-mediated destruction of pancreatic islet beta cells may result from a hyporesponsiveness in regulatory Th2 cells favoring a Th1 cell mediated environment in the pancreas. In the present study, we tested this possibility by analysis of the mechanisms of protection from IDDM afforded by IL 4 treatment in NOD mice. We show that IL-4 protects NOD mice from insulitis and IDDM when administered i.p. three times a week for 10 wk beginning at 2 wk of age. This occurs by the modulation of the homing of autoreactive cells to inflammatory sites and the stabilization of a protective Th2-mediated environment in the thymus, spleen, and pancreatic islets. Thus, IL-4 treatment favors the expansion of regulatory CD4+ Th2 cells in vivo and prevents the onset of insulitis and IDDM mediated by autoreactive Th1 cells. PMID- 9366393 TI - Inhibition of CTL induction by rapamycin: IL-2 rescues granzyme B and perforin expression but only partially restores cytotoxic activity. AB - Rapamycin (RAP) is a potent inhibitor of CTL induction. Since RAP is known to block IL-2 signaling through the IL-2R, we hypothesized that RAP may interfere with CTL generation by inhibiting IL-2-induced expression of granzyme (Gzm) B, perforin, and/or Fas ligand (FasL). MHC-unrestricted mouse CTL induced in vitro with anti-CD3 mAb in the presence of RAP (1 ng/ml) exhibited dramatically reduced cellular proliferation and cytotoxicity against P815 tumor target cells. Gzm B mRNA expression and enzymatic activity in RAP-treated CTL were greatly reduced compared with those in control CTL. Perforin mRNA expression was also reduced by RAP. In contrast, RAP failed to inhibit FasL mRNA expression. RAP, therefore, inhibits induction of the perforin/Gzm B cytolytic pathway but spares Fas/FasL mediated cytotoxicity. To determine whether RAP exerts a total blockade of the IL 2R signaling pathway, we induced CTL in the presence of both RAP and exogenous rIL-2 (100 U/ml). Under these conditions, Gzm B and perforin mRNA and protein expression as well as cellular proliferation were restored to at least control levels. Surprisingly, inhibition of cytotoxicity was only partially alleviated when CTL were induced in the presence of RAP plus rIL-2, even though CTL conjugated normally with target cells and had an intact granule secretory pathway. We conclude that 1) the inhibitory effect of RAP at the level of the IL 2R is incomplete; and 2) the suppressive effect of RAP on CTL induction is only partly due to inhibition of Gzm B and perforin gene expression. PMID- 9366394 TI - T cells from Jak3-deficient mice have intact TCR signaling, but increased apoptosis. AB - The Jak family tyrosine kinase, Jak3, is involved in signaling through cytokine receptors utilizing the common gamma-chain (gamma(c)). Mice and humans lacking Jak3 have severe immune deficiencies, including defects in B and T lymphocyte development and function. In particular, Jak3-deficient mice have mature T cells with an activated phenotype, yet these cells are functionally nonresponsive. In this work, we show that Jak3-deficient T cells have no gross defects in early T cell signaling, as measured by TCR-induced tyrosine phosphorylation and calcium mobilization responses. Furthermore, we find that Jak3-deficient mice expressing a transgenic TCR have extremely low numbers of peripheral T cells with a naive phenotype, indicating that both peripheral activation and expansion of Jak3-/- T cells are driven by antigenic signals. We show that, similar to gamma(c) deficient mice, T cells from Jak3-deficient mice have an increased susceptibility to apoptosis. Previously, we showed that when stimulated in vitro by CD3 plus CD28 cross-linking, Jak3-/- T cells secrete greatly reduced amounts of IL-2, and fail to proliferate. However, by measuring intracellular IL-2 levels, we find that Jak3-/- T cells produce amounts of IL-2 similar to activated T cells from control mice, further supporting the notion that there is no defect in TCR signaling in Jak3-/- T cells. PMID- 9366395 TI - Constitutive activation of JAKs and STATs in BCR-Abl-expressing cell lines and peripheral blood cells derived from leukemic patients. AB - An important step in the oncogenic transformation of hemopoietic cells and the subsequent development of leukemia is the proliferation of tumor cells in the absence of exogenous growth factors. In most cases of chronic myelocytic leukemia and in some cases of acute myelocytic leukemia and acute lymphocytic leukemia, the bcr-abl oncogene is involved in this process. Although the BCR-Abl oncoprotein demonstrates enhanced tyrosine kinase activity in leukemic cells, the mechanism by which this leads to growth factor independence remains poorly defined. One proposed mechanism is the activation of cytokine signal transduction pathways, possibly by an autocrine loop involving IL-3 and/or granulocyte macrophage CSF. Examination of several different cell lines expressing BCR-Abl demonstrates that some of these cells have constitutive activation of the JAK/STAT signaling pathway. We have found the constitutive activation of STAT5 in most, but not all, cell lines expressing BCR-Abl. This constitutive activation of STAT5 is variably associated with a corresponding activation of JAK kinases. Ab blocking studies show that the activation of STAT5 in these cell lines cannot be attributed to the activation of an IL-3/granulocyte-macrophage CSF-driven autocrine loop. Interestingly, samples of peripheral blood cells derived from patients with acute myelocytic leukemia and chronic myelocytic leukemia, which express BCR-Abl, demonstrate constitutive activation of STAT family members. These studies suggest that in a variety of leukemic states, BCR-Abl may use a bypass mechanism to activate cytokine signal transduction pathways. PMID- 9366396 TI - Proline-rich tyrosine kinase-2 activation by beta 1 integrin fibronectin receptor cross-linking and association with paxillin in human natural killer cells. AB - Recent evidence indicates that integrin ligation results in activation of focal adhesion kinase (pp125FAK), the prototype of a new subfamily of nonreceptor protein tyrosine kinase (PTK), including FAKB and the proline-rich tyrosine kinase 2 (PYK-2), also termed cell adhesion kinase-beta or related adhesion focal tyrosine kinase. We have previously shown that cross-linking of alpha 4 beta 1 and alpha 5 beta 1 fibronectin receptors on human NK cells stimulates tyrosine phosphorylation of two proteins migrating at 105 and 115 kDa. Here we report that cross-linking of beta 1 integrins on human NK cells stimulates tyrosine phosphorylation and PTK activity of PYK-2. PYK-2 tyrosine phosphorylation was maximal at 1 min and started to decline 20 min after stimulation. Engagement of alpha 4 beta 1 and alpha 5 beta 1 either with specific mAbs or after cell adhesion to fibronectin or its 120- and 40-kDa fragments also triggered PYK-2 tyrosine phosphorylation. Stimulation of PYK-2 tyrosine phosphorylation was inhibited by the tyrosine kinase inhibitor herbimycin A, but not by EGTA, indicating that PYK-2 tyrosine phosphorylation is PTK, but not calcium, dependent. We also demonstrate that PYK-2 is constitutively associated with paxillin, which undergoes tyrosine phosphorylation with the same kinetics of PYK 2 upon beta 1 integrin ligation. PMID- 9366397 TI - Impaired peripheral deletion of activated T cells in mice lacking the common cytokine receptor gamma-chain: defective Fas ligand expression in gamma-chain deficient mice. AB - Mice lacking the common cytokine receptor gamma-chain (gamma c) exhibit severely compromised lymphoid development. T cells that develop in these mice exhibit decreased Bcl-2 levels and accelerated apoptosis; nevertheless, these mice exhibit an age-dependent accumulation of activated CD4+ T cells. To investigate the basis for this accumulation, we analyzed both thymic and peripheral deletion in these mice. Gamma c-deficient mice had increased numbers of V beta 11+ T cells, consistent with a possible defect in Mtv-9-induced deletion; however, the deletion of V beta 5+ T cells by Mtv-9 and that of V beta 6+ T cells by Mls-1a were normal. Moreover, antigenic peptide could induce wild-type levels of deletion of CD4+ CD8+ thymocytes in TCR-transgenic gamma c-deficient mice. In contrast to this relatively normal deletion of thymocytes, bacterial superantigen (staphylococcal enterotoxin B)-induced elimination of peripheral T cells was greatly impaired, suggesting that defective peripheral deletion contributed to the accumulation of activated T cells. Interestingly, despite CD4+ T cell accumulation, these cells exhibited increased sensitivity to Fas-mediated death in vitro. Correction of the defect in Bcl-2 expression by mating to Bcl-2 transgenic mice augmented the splenic T cell accumulation and substantially enhanced the survival of gamma c-deficient T cells; however, these cells still exhibited significant Fas-mediated death, indicating that the increased Fas mediated death was not simply due to diminished Bcl-2 expression. Moreover, these T cells exhibit decreased expression of Fas ligand, suggesting that Fas-bearing cells cannot be effectively eliminated in vivo in gamma c-deficient mice. Thus, gamma c-dependent signals play a role in peripheral T cell deletion, presumably by inducing Fas ligand on activated T cells. PMID- 9366398 TI - The effect of NK cell activation by tumor cells on antigen-specific antibody responses. AB - In addition to mediating direct cytotoxicity, NK cells can exert regulatory effects on specific immune responses. For example, injection of poly (I:C) can alter specific Ab responses, which is attributable to the production of IFN-gamma by NK cells. To test whether direct activation of NK cells can exert the same effect, we have injected, at the same time as Ag challenge, BCL1-C11 tumor cells, which are highly effective inducers of IFN-gamma production by NK cells. The results show a specific enhancement of the IgG2a response, which does not occur with a tumor (70Z/3) that does not induce IFN-gamma production. This enhancement is NK cell and IL-12 dependent. However, BCL1-C11 cells cannot directly induce IL 12 production in peritoneal exudate cells (PECs). On the other hand, PECs from tumor-treated mice produce IL-12 in response to LPS, suggesting that they are primed in vivo. Furthermore, the IL-12 production is NK cell and IFN-gamma dependent. These results indicate that if tumor cells can directly activate NK cells to produce IFN-gamma, this cytokine initiates an amplification loop by activating macrophages to produce IL-12, which in turn activates NK cells further, resulting in the alteration of the isotype distribution of specific Ab responses. Production of the appropriate Ab isotype should enhance Ab-dependent cellular cytotoxicity against targets mediated by NK cells, implicating their role(s) in the specific immune response as well as the initial nonspecific phase. PMID- 9366399 TI - Derivation of HLA-A11/Kb transgenic mice: functional CTL repertoire and recognition of human A11-restricted CTL epitopes. AB - Transgenic mice expressing chimeric human (alpha1 and alpha2 HLA-A11 domains) and murine (alpha3, transmembrane, and cytoplasmic H-2Kb domains) class I molecules were derived. These mice were used as a model system to study the immunogenicity of human CTL epitopes and also to examine the aspects of Ag processing differences of mice vs man. Immunization of these mice with seven known HLA-A11 restricted CTL epitopes emulsified in IFA resulted in vigorous specific CTL responses. A larger panel of 45 A11-binding peptides was used to examine the relationship between immunogenicity in the HLA-A11/Kb transgenic mice and HLA-A11 binding capacity. Twenty-one of 28 (75%) peptides with high binding affinities (50% inhibitory concentration (IC50), 2-50 nM) and 7 of 13 (54%) intermediate binding peptides (IC50, 50-500 nM range) were immunogenic. In parallel, 19 of these peptides were used for in vitro primary immunizations of PBMC derived from HLA-A11 healthy human donors. It was found that 8 of 8 peptides that were able to elicit CTL in primary human in vitro cultures were also immunogenic in HLA-A11/Kb mice. Finally, HLA-A11/Kb transgenic mice were found to generate an A11/Kb restricted CTL response following immunization with influenza virus A/PR/8/34, suggesting that, at least to some extent, A11 epitopes are generated by transgenic mice as a result of natural in vivo processing and presentation. PMID- 9366400 TI - CD4+ CD8+ thymocytes are preferentially induced to die following CD45 cross linking, through a novel apoptotic pathway. AB - Ligation of the protein tyrosine phosphatase CD45 on both mature and immature T cells modulates the amplitude of TCR-mediated signals. In this work, we have evaluated the consequences of CD45 ligation on immature T cells, in the absence of TCR engagement. Cross-linking of CD45 on thymocytes by mAbs led to the induction of cellular death, characterized by a reduction in mitochondrial membrane potential (delta psi(m)), production of reactive oxygen species, loss in membrane asymmetry, exposure of phosphatidylserine residues, and incorporation of vital dyes. In sharp contrast to most stimuli causing thymocyte death, CD45 cross linking did not lead to DNA degradation. Cell death was not blocked by Bcl-2 overexpression or treatment with caspase inhibitor. However, death was inhibited by the addition of scavengers of reactive oxygen species. We also established that susceptibility to CD45-mediated death is acquired during the transition of early CD4- CD8- TCR- T cell precursors into CD4+ CD8+ TCR- thymocytes and is increased with further acquisition of surface TCR on these cells. Moreover, mature thymocytes were much less sensitive to CD45 cross-linking than CD4+ CD8+ cells. We propose that during T cell development, CD45 ligation could induce the death of those immature thymocytes that do not fulfill the requirements for positive selection. PMID- 9366401 TI - Induction of tolerance by IL-10-treated dendritic cells. AB - Dendritic cells (DC) form a specialized system for presenting Ag to naive or quiescent T cells and consequently play a central role in the induction of T and B cell immunity. In this study we used DC generated from peripheral progenitors to analyze the effect of IL-10 on the accessory function of human DC. We demonstrate that immature DC, harvested on days 9 to 11 and exposed to IL-10 for the last 2 days of culture, show a strongly reduced capacity to stimulate a CD4+ T cell response in an allogeneic MLR in a dose-dependent manner. In contrast, fully mature DC are completely resistant to the effects of IL-10. These results were obtained in both an alloantigen-induced MLR and an anti-CD3 mAb-induced response of primed and naive (CD45RA+) CD4+ T cells. FACS analysis revealed inhibition of the up-regulation of the costimulatory molecules CD58 and CD86 and the specific DC marker CD83 in DC pretreated with IL-10. These data suggest that IL-10 inhibited the development of fully mature DC. Furthermore, DC precultured with IL-10, but not controls, induced a state of alloantigen-specific anergy in CD4+ T cells and of peptide-specific anergy in the influenza hemagglutinin specific T cell clone HA1.7. Analysis of the supernatants of these anergic T cells revealed a reduced production of IL-2 and IFN-gamma compared with that in control cells. Collectively, these data suggest that IL-10 converts immature DC into tolerogenic APC, which might be a useful tool in the therapy of patients with autoimmune or allergic diseases. PMID- 9366403 TI - Induction of parasite antigen-specific antibody responses in unsensitized human B cells is dependent on the presence of cytokines after T cell priming. AB - Using two recombinant filarial protein Ags and keyhole limpet hemocyanin, we sensitized T cells from uninfected, nonatopic individuals in such a manner that they were able to provide help for the selective induction of an Ag-specific Ab response. IL-2 and IL-4 were shown to be critical for sensitizing the T cells; once sensitized, these T cells could provide the necessary signals for B cells to produce Ag-specific Abs, provided that IL-4 (or IL-2) was supplied exogenously. Primary exposure of T cells to IFN-gamma, but not to IL-12, prevented the Ag sensitized T cells from helping B cells to produce specific Abs, apart from the IgG2 isotype. These data suggest that Ab-producing B cells of a defined Ag specificity and isotype can be generated differentially after in vitro priming of human T cells by Ag, providing regulatory cytokines are also present. PMID- 9366402 TI - Beta 2-microglobulin-deficient mice are protected from hypergammaglobulinemia and have defective antibody responses because of increased IgG catabolism. AB - The goal of this study was to determine whether class I proteins play an important role in the regulation of Ig and to elucidate the mechanism(s) involved. We analyzed the phenotype imposed by a null allele of beta 2 microglobulin (beta 2m). Serum Ig levels of several mouse strains showed a beta 2m dependence that was most evident in mice genetically predisposed to develop chronic systemic lupus erythematosus, was preferential to IgG isotypes, and was greatly exaggerated in aging mice that normally develop hypergammaglobulinemia. Beta 2m-deficient mice, regardless of genetic background, also displayed a substantial reduction of specific Ab in response to a prototypic T cell-dependent Ag and a prototypic T cell-independent 2 Ag. This reduction could be accounted for by a selective diminution of Abs of the IgG class. Therefore, class I proteins play a considerable role in the regulation of Ig. The beta 2m dependence could not be explained by class I-dependent immunoregulatory cells (CD8+ cells, NK1.1+ T cells, or conventional NK+ cells) or by the transfer of maternal IgG into the prenatal/neonatal mouse made possible by the beta 2m-dependent Fc receptor (FcRn). However, a beta 2m-dependent increase in the half-lives of IgG, presumably conferred by lifelong FcRn expression, was observed in all mice regardless of genetic background and age. We conclude that FcRn-mediated protection of IgG from catabolism is a generic mechanism that best explains the lifelong beta 2m dependence of Ig in both normal and pathologic situations. PMID- 9366404 TI - Expression of a hypoglycosylated form of CD86 (B7-2) on human T cells with altered binding properties to CD28 and CTLA-4. AB - CD80 (B7-1) and CD86 (B7-2) on APC provide a major costimulatory signal through interactions with CD28 on T cells. Absent from resting human T cells, CD86 is up regulated early upon T cell activation, whereas CD80 expression appears later. Whereas T cell expression of CD80 has been implicated in costimulation, the functional significance of CD86 expression on T cells is unclear. We now demonstrate that CD86 expressed on human CD4+ T cell clones does not provide a costimulatory signal for other CD4+ T cell clones. Binding studies using CD28-Ig and CTLA-4-Ig fusion proteins demonstrate that CD86 expressed on T cells has significantly reduced binding affinity for CTLA-4 and no detectable binding to CD28. Biochemical analysis demonstrates that post-translational modifications of CD86 in human T cells are different from those of CD86-transfected Chinese hamster ovary cells or EBV-transformed B cells, in that T cells express a hypoglycosylated form of CD86 on the surface membrane. Thus, our results suggest that while CD86 is expressed on a number of different cell types, its costimulatory function and affinity for its ligands may be regulated by cell type specific post-translational modifications. PMID- 9366406 TI - Pivotal role of endogenous TNF-alpha in the induction of functional inactivation and apoptosis in NK cells. AB - The interaction of purified nonactivated human NK cells with target cells overnight results in functional anergy and apoptosis in NK cells and in a change of the NK phenotype from CD16+ CD56+ CD69- to CD16(dim/-) CD56(+/dim/-) CD69+. These studies suggested that signaling triggered by the FcR CD16 may be implicated in target cell-mediated anergy/apoptosis of NK cells. We hypothesized that triggering CD16 by anti-CD16 Ab should result in NK cells exhibiting functional and phenotypic properties similar to those obtained following triggering of NK cells with target cells. The findings demonstrate that the anti CD16 mAb-treated NK cells acquired the CD16- CD56(+/dim) CD69+ Fas+ phenotype and lost their cytotoxic function, a significant number of the NK cells underwent apoptosis, and a selective induction of TNF-alpha synthesis and secretion was observed. The coaddition of IL-2 to anti-CD16 Ab-treated NK cells resulted in enhanced secretion of TNF-alpha and augmentation of the frequency of cell death. However, a minor subset of NK cells exhibited potent cytotoxic function and proliferated. The anti-CD16-induced effects in NK cells were largely abrogated by the addition of either anti-TNF-alpha Ab or TNF-binding protein in the cultures. There was an enhancement of NK cell killing following the addition of exogenous TNF-alpha into the culture. Cytochalasin B selectively triggered the secretion of TNF-alpha and significantly augmented the frequency of apoptosis of anti-CD16 treated NK cells. These findings demonstrate an important and pivotal role of endogenous TNF-alpha synthesis and secretion by NK cells in the induction of functional anergy and apoptosis in anti-CD16-treated NK cells. PMID- 9366405 TI - Alpha 4 beta 1 integrin-mediated tyrosine phosphorylation in human T cells: characterization of Crk- and Fyn-associated substrates (pp105, pp115, and human enhancer of filamentation-1) and integrin-dependent activation of p59fyn1. AB - Integrin adhesion receptors transduce signals that transmit information from the extracellular environment to the cell interior. Although integrins lack intrinsic tyrosine kinase activity, stimulation of the alpha 4 beta 1 integrin on human H9 T cells results in rapid tyrosine phosphorylation of proteins in the 105 to 115 kDa range. In this study, we report that alpha 4 integrin stimulation of H9 T cells results in tyrosine phosphorylation of three distinct proteins: pp105, pp115, and human enhancer of filamentation 1 (HEF1), all of which associate with the adapter protein c-Crk. However, pp115 can be distinguished from pp105 and HEF1 by its ability to associate with the SH2 domain of the tyrosine kinase p59fyn. Both pp105 and pp115 are antigenically distinct from HEF1, p130Cas, pp125FAK, Pyk2, p120cbl, and the p110 subunit of phosphatidylinositol 3-kinase. The functional significance of pp115 association with p59fyn is suggested by the ability of alpha 4 integrin stimulation to activate Fyn tyrosine kinase activity. These studies show that alpha 4 integrin stimulation of T cells results in the tyrosine phosphorylation of several distinct substrates. The association of these substrates with intracellular signaling intermediates, such as Crk and Fyn, may play a critical role in integrin-mediated regulation of T cell function. PMID- 9366407 TI - Kinase-independent potentiation of B cell antigen receptor-mediated signal transduction by the protein tyrosine kinase Src. AB - Signal transduction mediated by the B cell Ag receptor involves the activation of multiple protein tyrosine kinases that are members of the Src family (i.e., Fyn, Lyn, Blk, Lck). To determine whether members of the Src family possess common physical and/or enzymatic properties that enable them to potentiate signal transduction via the B cell Ag receptor, we expressed the protein tyrosine kinase Src in the B lymphoma cell line K46-17 mu m lambda. Based on coprecipitation analysis and two-color immunofluorescence, this heterologous Src family kinase was observed to physically associate with the B cell Ag receptor. Additional experiments demonstrated that B cell Ag receptor cross-linking results in increased tyrosine phosphorylation and activation of Src. Several parameters of B cell activation, including tyrosine phosphorylation of intracellular substrates, calcium mobilization, and transcription factor activation, were potentiated in cells that expressed Src when compared with control cells. To determine whether potentiation of Ag receptor-mediated signaling by Src was dependent on its catalytic activity, a kinase-deficient form of Src was expressed in K46-17 mu m lambda cells. Transfectants expressing kinase-deficient Src exhibited an enhanced responsiveness to stimulation through the B cell Ag receptor that was comparable with transfectants expressing wild-type Src. Additionally, kinase-deficient Src was observed to associate with the endogenous kinase Lyn in an activation dependent manner. These findings indicate that members of the Src family may potentiate Ag receptor-mediated signaling via a kinase-independent mechanism(s) that involves amplification of kinase recruitment to the Ag receptor activation complex. PMID- 9366408 TI - Bcl-x protects primary B cells against Fas-mediated apoptosis. AB - Primary murine splenic B cells are rendered sensitive or resistant to Fas mediated apoptosis in a receptor-specific fashion. B cells stimulated though CD40 are Fas sensitive unless they also receive a signal though surface Ig that produces a state of resistance to Fas killing. Protection from Fas-mediated apoptosis takes time to develop and requires ongoing macromolecular synthesis; therefore, it appears to involve the induction and accumulation of one or more gene products. The role of Bcl-x was evaluated by examining the expression and function of this gene in primary B cells. bcl-x mRNA was induced by anti-IgM treatment of otherwise sensitive (CD40 ligand-treated) B cells. Bcl-x protein expression was induced by anti-IgM and appeared in a time frame that correlates well with the onset of anti-IgM-induced Fas resistance. Further, B cells from Bcl x Tg mice were found to be resistant to Fas-mediated apoptosis. These results strongly suggest that the protection against Fas killing afforded by cross linking surface Ig is mediated, at least in part, by an increase in Bcl-x. PMID- 9366409 TI - TNF-alpha bifunctionally induces proliferation in primary hepatocytes: role of cell anchorage and spreading. AB - In the absence of a growth factor or an appropriate extracellular matrix (ECM), cells are arrested in the G0/G1 phase. In this report, we demonstrate the evidence that TNF-alpha induced DNA synthesis of primary mouse hepatocytes in vitro by activating two distinct pathways. TNF-alpha induced drastic spreading of hepatocytes on hydrophobic plastic, while the adhesion was not influenced. The effect was time and dose dependent. The cell spreading was accompanied by the phosphorylation of paxillin, indicating the stimulation of focal adhesion molecules. TNF-alpha-induced spreading of hepatocytes was not transient, and kinetic analysis and morphologic observation suggest that the effect was different from epidermal growth factor- or hepatocyte growth factor-induced transient hepatocyte spreading. TNF-alpha-induced hepatocyte spreading was blocked by cytochalasin D, Arg-Gly-Asp peptides, cycloheximide, or anti-integrin beta1 Ab. Results of competitive PCR for ECM proteins demonstrated that TNF-alpha increased the expression of laminin alpha3 and gamma1 chains in hepatocytes. These data suggested that TNF-alpha induced cell anchorage for hepatocytes by up regulating ECM production. More importantly, TNF-alpha, but neither epidermal growth factor nor hepatocyte growth factor, induced DNA synthesis following the spreading in primary hepatocytes on hydrophobic plastic, while mere cell spreading on collagen did not induce DNA synthesis. The DNA synthesis was blocked by the inhibition of either cell spreading or DNA polymerase, demonstrating that TNF-alpha induced DNA synthesis in primary hepatocytes by activating two distinct pathways, i.e., forming the scaffold and inducing growth signals. Taken together, TNF-alpha bifunctionally regulates the proliferation of primary hepatocytes, serving as both an ECM inducer and a growth factor. PMID- 9366410 TI - Expansion of mature thymocyte subsets before emigration to the periphery. AB - A small population of DNA-synthesizing mature thymocytes could be defined by analyzing cell surface markers and 5-bromo-2'-deoxyuridine (BrdUrd) labeling by four-color cytofluorometry. These cells have a completely mature phenotype (CD4- CD8+ or CD4+ CD8- TCR(high), HSA-, Qa-2(high)) and expand only weakly after BrdUrd incorporation. They recovered immediately in total number and in DNA synthesis rate after treatment with the antimitotic drug demecolcin, thus much faster than immature CD4+ CD8+ thymocytes. These data demonstrate the existence of a late intrathymic expansion phase, independent of that of developing CD4+ CD8+ immature cells, and involving phenotypically mature cells renewed each day. In mixed chimeras prepared by transfer of bone marrow and lymph node cells into RAG-2(-/-) mice, all cycling mature thymocytes were bone marrow derived. They are thus produced in situ and do not correspond to peripheral T cells reentering the thymus. Double FITC/BrdUrd detection showed that a high proportion (10-20%) of recent thymic emigrants were BrdUrd+ just postcycling cells and that around 50% of cycling mature thymocytes are just ready to emigrate to the periphery in the few hours after DNA synthesis. The late intrathymic expansion phase demonstrated here increases the daily thymic cell export by at least 30%. It could play a role in the adjustment of the T cell repertoire before emigration and in the regulation of the thymic cell output into the peripheral T cell pool. PMID- 9366411 TI - Activated T helper 1 and T helper 2 cells differentially express the beta-2 adrenergic receptor: a mechanism for selective modulation of T helper 1 cell cytokine production. AB - We recently reported that resting clones of murine Th1 cells, but not resting Th2 cells, expressed a detectable level of the beta-2-adrenergic receptor (beta 2AR). In the present study, we proposed that the level of beta 2AR expression on anti CD3 mAb-activated CD4+ effector Th cells may differ from the level on resting cells, and that a change in receptor expression may alter the functional responsiveness of these cells to either the beta 2AR-selective ligand terbutaline or the sympathetic neurotransmitter norepinephrine. Following anti-CD3 activation, the beta 2AR was expressed on Th1 cells, but not Th2 cells. The number of binding sites on Th1 cells was maintained, with no change in affinity, over a 24-h activation period. When Th clones were exposed to terbutaline following anti-CD3 activation, Th1 cell, but not Th2 cell, cytokine production was modulated. IL-2 production by Th1 cells was decreased, while IFN-gamma production was not significantly altered. The decrease in IL-2 production was concentration dependent and was blocked by an antagonist. In comparison with control supernatants, the lower level of IL-2 present in terbutaline-exposed culture supernatants supported the proliferation of an IL-2-dependent Th1 clone to a lesser degree. Additionally, norepinephrine down-modulates IL-2, but not IFN gamma, production by binding specifically to the beta-adrenergic receptor. Thus, a detectable level of the beta 2AR is expressed on activated Th1 cells, but not activated Th2 cells, thereby providing a mechanism by which IL-2 production is preferentially modulated by an endogenous and therapeutic ligand following Th1 cell activation. PMID- 9366412 TI - Bacterial lipoprotein and lipopolysaccharide act synergistically to induce lethal shock and proinflammatory cytokine production. AB - Septic shock is a major cause of death in the world. Although much is known about the role of LPS in septic shock, little is known about the role of other bacterial components. Lipoprotein (LP) is a major component of bacteria in the family Enterobacteriaceae. LP purified from Escherichia coli was shown to induce TNF-alpha and IL-6 production in peritoneal exudate macrophages obtained from LPS responsive (C3H/HeOuJ) and LPS-nonresponsive (C3H/HeJ) mice. LP and LPS acted synergistically to induce cytokine production not only in C3H/HeOuJ macrophages but also in C3H/HeJ macrophages. These results suggest that LPS can induce cellular signaling in C3H/HeJ macrophages, and that LPS and LP activate macrophages via different receptors and/or signaling pathways. The role LP plays in septic shock was investigated using the mouse D-galactosamine model. LP induced lethal shock and in vivo production of TNF-alpha and IL-6 in both LPS responsive and LPS-nonresponsive mice. LPS failed to induce lethal shock or in vivo cytokine production in C3H/HeJ mice. However, LP and LPS acted synergistically in inducing lethal shock and in vivo cytokine production in both LPS-responsive and LPS-nonresponsive mice. Finally, a heat-killed preparation of an E. coli mutant strain that lacked LP was shown to be less efficient than heat killed wild-type E. coli at inducing lethal shock in C3H/HeJ mice. Collectively, these results suggest that LP and LPS induce cytokine production via different mechanisms and that LP plays an important role in septic shock induced by bacteria in the family Enterobacteriaceae. PMID- 9366413 TI - A gain of novel tissue specificity in the human Ly-6 gene E48. AB - The Ly-6 Ag family consists of glycosyl-phosphatidylinositol-anchored surface proteins with a molecular mass of about 15 kDa. Seven members of the murine family have been characterized, and from five of these the genes have been cloned. Three members of the human family have been characterized: CD59, Ag E48, and the RIG-E or TSA-1/Sca-2 Ag. Most of the genes are expressed on lymphocytes, but some are expressed on other tissues as well. The mapped genes of the murine Ly-6 Ags, as well as of CD59, were shown to have a highly conserved structure, each consisting of four exons. The human E48 Ag was originally identified as a target Ag for radioimmunotherapy of patients with squamous cell carcinoma. The Ag is expressed on keratinocytes, but evidently not on lymphocytes. Molecular cloning of the cDNA encoding the Ag revealed that this Ag is most likely the human homologue of the murine Ly-6 Ag, ThB. In this paper, we describe that, in contrast to all other Ly-6 genes, the gene encoding the human E48 Ag consists of only three exons. Sequences at the 5' end of the transcription start site were shown to drive keratinocyte-associated expression. These data suggest that the functional elimination of an ancestral Ly-6 exon 1 switched the expression from lymphocytes toward keratinocytes. PMID- 9366414 TI - Naturally occurring A pocket polymorphism in HLA-B*2703 increases the dependence on an accessory anchor residue at P1 for optimal binding of nonamer peptides. AB - Previous studies have shown the B*2703 subtype of HLA-B27, which differs from B*2705 and other MHC class I molecules by having a His substituted for Tyr at position 59 in the A pocket, inefficiently presents certain B*2705-restricted peptides. The current work investigates the influence of the first peptidic amino acid (P1) on peptide binding to B*2705 and B*2703. Results show P1 has a marked effect for both subtypes, with relative affinities (EC50) of P1-substituted peptides spanning four orders of magnitude. All peptides tested bind better to B*2705 than to B*2703. However, Lys, Arg, Phe, or Trp at P1 result in a < or = 2 fold difference between subtypes, while other amino acids produce greater differences (maximum approximately 50-fold for Leu). Self peptides eluted from B*2703, as well as two viral epitopes, have a motif similar to B*2705 peptides, except for a stronger preference for Lys or Arg at P1, consistent with peptide binding data. Computer modeling of B*2703 reveals movement of a water molecule and the alpha1 alpha-helix to allow His at position 59 to maintain important hydrogen bonds with the peptide N terminus in the A pocket. However, these bonds are weaker, and the water molecule movement results in the loss of a hydrogen bond with Glu-45 in the B pocket. We conclude that B*2703, as a consequence of its unique A pocket polymorphism, appears to have a greater dependency on an accessory anchor residue at P1 to maintain tight binding of peptides. PMID- 9366415 TI - Characterization of CD40 signaling determinants regulating nuclear factor-kappa B activation in B lymphocytes. AB - CD40 signaling to B cells is important for generating an effective humoral immune response. CD40 ligation leads to B cell activation events such as proliferation, Ig secretion, isotype switching, and up-regulation of cell surface molecules, as well as the generation of memory B cells. Many of these events are dependent upon the ability of CD40 to activate the transcription factor NF-kappa B (NF-kappa B). To define the CD40 signaling components upstream of NF-kappa B activation and the functional consequences downstream of NF-kappa B activation, we examined mouse B cell transfectants expressing wild-type or mutant human CD40. Analysis of CD40 cytoplasmic domain truncation and point mutants defined a 10-amino acid CD40 cytoplasmic signaling determinant required for NF-kappa B activation. A threonine residue at position 234, previously shown to be important for CD40 association with TNF receptor-associated factor 2 (TRAF2), TRAF3, and TRAF5, was not required for NF-kappa B activation. This suggests that in B cells, CD40-induced NF-kappa B activation can occur independently of TRAF2 and TRAF5 association. NF-kappa B activation was independent of the transmembrane domain of CD40, suggesting that it is independent of p23, a molecule that associates with CD40 in a region other than the cytoplasmic domain. Proteasome-dependent inhibitory kappa B alpha (I kappa B alpha) and I kappa B beta degradation occurred downstream of CD40 ligation and preceded CD40-mediated NF-kappa B nuclear translocation. CD40- or pervanadate-mediated I kappa B tyrosine phosphorylation was not detected. NF kappa B activation correlated with the ability of CD40 to induce Ab secretion and the up-regulation of ICAM-1 and LFA-1. However, NF-kappa B activation was insufficient for CD40-mediated up-regulation of B7-1, Fas, and CD23. PMID- 9366416 TI - Appropriate developmental expression of human CD8 beta in transgenic mice. AB - The human CD8 glycoprotein is expressed either as an alpha beta heterodimer or as an alpha alpha homodimer on thymocytes, mature T cells, and subpopulations of intestinal intraepithelial lymphocytes (IELs). The homodimeric form of CD8 is exclusively expressed on TCR gamma delta IELs and on subsets of NK cells and TCR alpha beta IELs. To understand the molecular mechanisms by which these genes are regulated, we created transgenic mice with a 95-kb human genomic DNA fragment containing the entire CD8 beta gene as well as a cluster of tissue-specific DNase I-hypersensitive sites 7 to 10 kb upstream of the gene. These sites were present in CD8 alpha beta+- but not CD8 alpha beta- T cell lines nor in a B cell line. We found that transgenic mice had correct developmental expression of human CD8 beta on thymocytes and mature CD8+ cells and no expression on mature CD4+ T cells or B cells. Interestingly, the percentage of mouse CD8 alpha+ cells that were human CD8 beta+ varied, depending on the founder line, from 4 to 88%, whereas the percentage among siblings was similar, indicative of a variegated phenotype resulting from site of integration effects. Expression was also observed on intestinal IELs, but only on those expressing the TCR alpha beta receptor and not the TCR gamma delta cells, which exclusively express CD8 alpha alpha. Of the TCR alpha beta+ cells, the transgene was expressed in both the CD8 alpha alpha and alpha beta subpopulations. These results indicate that this 95-kb fragment affords developmentally correct expression of the human CD8 beta gene on thymus derived T cells in transgenic animals. Therefore, CD8 lineage-specific regulatory sequences must be located within the fragment. PMID- 9366417 TI - A 150-base pair 5' region of the MHC class I HLA-B7 gene is sufficient to direct tissue-specific expression and locus control region activity: the alpha site determines efficient expression and in vivo occupancy at multiple cis-active sites throughout this region. AB - To characterize cis- and trans-acting mechanisms that regulate MHC class I transcription during development and in adult tissues, we have used transgenic mice to study a series of human MHC (HLA)-B7 class I gene constructs. Previous studies identified the 5' -0.66-kb to -0.075-kb region as sufficient to direct appropriate and efficient tissue-specific levels of HLA-B7 RNA relative to H-2 class I. Results here show that DNA 5' of -0.26 kb is not required for any aspect of expression. As the expression level correlated with the transgene copy number, was comparable to H-2 or a per-gene copy basis and was independent of integration site, the -0.075 to -0.26-kb segment also functions as a locus control region. With this region, sequences 3' of -0.075 kb, possibly at the promoter, appear to direct the appropriate tissue distribution. Of conserved sequences in the -0.075 to -0.26-kb region, enhancer B box is nonessential. In contrast, in vivo "footprinting" implicated region I/ enhancer A/NF-kappaB, IFN consensus/response sequence, and alpha in class I regulation as they are "occupied" in a tissue specific pattern that correlates with expression. Mutation of alpha leads to decreased expression and loss of occupancy not only at alpha but also at region I/enhancer A/NF-kappaB and IFN consensus/response sequence. Thus, site alpha is an essential class I regulatory element, the dominant function of which is to mediate tissue-specific occupancy at multiple adjacent cis-active sites, possibly by facilitating stable synergistic interactions between factors at these distinct elements. PMID- 9366418 TI - Evidence that Tmevd2 and eae3 may represent either a common locus or members of a gene complex controlling susceptibility to immunologically mediated demyelination in mice. AB - Theiler's murine encephalomyelitis virus (TMEV)-induced demyelination and experimental allergic encephalomyelitis are the principal immunologically mediated, genetically controlled models of multiple sclerosis. Previous studies using different mapping techniques identified susceptibility loci for both diseases on chromosomes 3, 6, and 17. To more precisely map these TMEV and experimental allergic encephalomyelitis loci relative to each other, linkage analysis using microsatellite markers and a (BALB/cByJ x DBA/2J) x BALB/cByJ backcross population segregating for TMEV-induced disease was conducted. Comparisonwise and chromosomewise critical values based on permutation theory were estimated for each chromosome. Evidence for linkage to markers on chromosome 17 was not seen. Chromosomewise linkage (p = 0.13) was detected with D6 Mit36 and D6 Mit149 (marker-specific chromosomewise p values = 0.02) at 40.4 cM on chromosome 6. Chromosomewise linkage (p < 0.01) (marker-specific chromosomewise p value = 0.0) and comparisonwise linkage (p < < 0.0001) to D3 Mit156 at 33.9 cM on chromosome 3 were observed along with chromosomewise linkage (p < 0.05) and comparisonwise linkage (p < < 0.0001) to D3 Mit29, D3 Mit311, D3 Mit28, and D3 Mit11 from 33.9 to 37.2 cM, respectively. Significant linkage to D3 Mit156 places Tmevd2 1.1 cM proximal of D3 Mit101 (35 cM), the maximally linked marker to the eae3 susceptibility gene. Maximum likelihood estimates conducted by multilocus linkage analysis localized Tmevd2 within a 95% confidence interval bordered by D3 Mit29 and D3 Mit10, at 33.9 and 37.2 cM, respectively. Taken together these results suggest that Tmevd2 and eae3 may represent either a single, common susceptibility gene or members of a gene complex involved in central nervous system immunopathology. PMID- 9366419 TI - HLA-DP2: self peptide sequences and binding properties. AB - Although self peptides bound to HLA-DQ and, especially, HLA-DR allotypes have been described in some detail, few ligands that bind to HLA-DP have been identified. Toward this aim, naturally processed peptides were isolated from immunoaffinity-purified HLA-DP2 molecules expressed in cultured B lymphocytes. The size distribution of the peptide repertoire is generally similar to those reported for self peptides bound to HLA-DR and HLA-DQ molecules. Twelve peptides representing individual sequences including two nested sets were sequenced by mass spectrometry and/or N-terminal Edman analysis. Source proteins included MHC molecules and other integral membrane proteins as well as secretory and serum proteins. No dominant amino acid markers suggestive of particular enzymatic processing events were detected. Peptide specificity and affinity were examined in binding assays using synthetic peptides and purified HLA-DP and HLA-DR molecules. Anchor residues were tentatively assigned using alanine-substituted analogues of two self peptides. Some structural features of HLA-DP2 that may relate to peptide binding are considered. PMID- 9366420 TI - Autoantigen recognition by human CD8 T cell clones: enhanced agonist response induced by altered peptide ligands. AB - Determination of immunodominant epitopes of MHC class I-restricted self-Ags and elucidation of TCR contact residues is of potential importance in providing a means of manipulating the immune response to self-Ags in human autoimmune diseases. A computer algorithm was used to examine the sequences of the two major encephalitogenic proteins of myelin, MBP and PLP, for HLA-A2 binding motifs. Thirty-eight peptides with HLA-A2.1 binding motifs were synthesized and their binding to HLA-A2.1 was measured. A panel of HLA-A2-restricted T cell clones directed against the PLPp80-88 epitope, which exceeded the binding affinity of the other myelin-peptides tested by at least one order of magnitude, was generated. Using a set of analogue peptides with single amino acid substitutions, we detected a distinct pattern of TCR contact residues for each clone. Surprisingly, modification of different presumed TCR contact residues generated superagonist peptides, which are defined as peptides with equal or lower MHC binding affinity to HLA-A2 that induce half-maximal effector responses at 100 fold lower concentrations than the original peptide. These agonist peptides could drive cytotoxic T cell clones to proliferate, secrete cytokines, and clonally expand at concentrations at which the native peptide induced only cytotoxic responses. The proliferation induced by the superagonist peptides gives additional evidence that the clonal expansion of CD8 T cell clones may in part be regulated on the level of Ag recognition by the TCR. PMID- 9366421 TI - The neuropeptide substance P activates transcription factor NF-kappa B and kappa B-dependent gene expression in human astrocytoma cells. AB - The neuropeptide substance P is a major mediator of neurogenic inflammation and immunomodulatory activities within the central and peripheral nervous system. In several cell types, substance P induces the expression of proinflammatory cytokines that have been implicated in the pathogenesis of different neuropathologies. Substance P preferentially binds to NK-1, a receptor of the neurokinin family, but how the receptor-elicited signal is translated into inflammatory gene expression is not yet understood. In this work, we describe that in U373 MG astrocytoma cells, nanomolar concentrations of substance P potently triggered activation of NF-kappa B, a transcription factor involved in the control of cytokine expression and apoptosis. Substance P-induced NF-kappa B activation was associated with the increased mRNA expression and secretion of IL 8, an NF-kappa B-controlled target gene. The stimulatory effect of substance P was specific, since an NK-1-selective receptor antagonist completely prevented NF kappa B activation in response to substance P, but not IL-1 beta. In addition, we show that the activity of substance P required mobilization of intracellular calcium and formation of reactive oxygen intermediates as second messengers. Our results suggest that NF-kappa B may be an important component controlling neurogenic inflammation within the peripheral and central nervous system. PMID- 9366422 TI - Characterization of murine CD70, the ligand of the TNF receptor family member CD27. AB - Human CD70 (CD27 ligand) is a type II transmembrane glycoprotein belonging to the TNF family. The protein is not expressed on resting lymphocytes, but is rapidly induced on these cells after cellular activation. Importantly, interaction of CD70 with its receptor CD27 gives a costimulatory signal for lymphocyte activation. Whereas CD27 has been molecularly characterized in the mouse, murine CD70 (mCD70) was undefined until now. Here, we describe the cDNA cloning and initial characterization of mCD70 and the determination of its gene structure. mCD70 is a polypeptide of 195 amino acids that has 62% homology with its human counterpart. In analogy to human CD70, mCD70 transcript levels are strongly but transiently up-regulated during lymphocyte activation, which is in line with a role for the CD27-CD70 receptor pair early in the immune response. In accordance with the comitogenic activity of mCD27-specific mAb, recombinant mCD70 potently costimulates T cell proliferation. Finally, the mCD70 gene consists of three exons spanning approximately 4 kb of DNA and is localized on chromosome 17. PMID- 9366423 TI - Enhancement of natural killer cell cytotoxicity by the human herpesvirus-7 via IL 15 induction. AB - NK cells, a key component of the innate immune system, are known to play an important role against viral infections. Previously, we reported that the human herpesvirus-6 (HHV-6) induces IL-15 in human PBMC and increases their NK activity. We describe in this work that another human herpesvirus, HHV-7, which shares genomic homology with HHV-6, also causes up-regulation of NK cell cytotoxicity via IL-15 induction. The NK cell activity of the PBMC from different donors displayed a variable range of enhancement after treatment with HHV-7. This enhancement occurred within a few hours of exposure to the virus and was blocked by Abs to IL-15, but not to other cytotoxicity-enhancing cytokines (i.e., to IFN gamma, IL-2, TNF-alpha, or IL-12). Our results also show that this HHV-7-induced IL-15-mediated activation of NK cells occurs via IL-2R, since HHV-7-enhanced NK cytotoxic activity could be blocked completely by anti-IL-2R beta-chain mAb (anti CD122). The up-regulation of NK cell cytotoxicity did not require infectious virus, as the use of UV-irradiated HHV-7 produced similar results. This effect was virus specific because it was abrogated by neutralizing the virus with human sera containing Abs to HHV-7. We also found increased amount of IL-15 transcripts in HHV-7-treated PBMC as compared with the untreated PBMC. Taken together, these results would suggest that host responds to HHV-7 infection by up-regulating IL 15 production, which then results in an enhancement of NK cell activity; this, in turn, may play a major role in the control of the viral infection. PMID- 9366425 TI - Alteration of macrophage function by a Trypanosoma cruzi membrane mucin. AB - Cytokines secreted by macrophages play important roles in the immune response to Trypanosoma cruzi. Here, we report that a purified glycosylphosphatidylinositol (GPI)-anchored mucin from the T. cruzi membrane, Ag C10, is able to bind to the macrophage cell surface and blocks the subsequent binding of mAb against CD62L/L selectin, whereas binding of mAbs directed against other monocyte surface molecules is unaffected. In addition, Ag C10 binding to macrophages triggered a CD54/ICAM-1-mediated cell adhesion as well as an increase in intracellular Ca2+, which was further augmented by cross-linking the Ag C10-bound surface receptors by mAb against Ag C10. Interestingly, Ag C10-treated monocytes secreted IL-1beta, but not TNF-alpha or IL-12. Moreover, these cells could secrete IL-1beta, but not TNF-alpha or IL-12, after activation with LPS. T. cruzi-infected macrophages displayed similar alterations in cytokine secretion, with an impaired ability to secrete IL-12 and TNF-alpha, but not IL-1beta, upon LPS activation. These effects were substantially inhibited by neutralizing mAb against Ag C10. These effects appeared to take place at the transcriptional level, since mRNA for TNF-alpha, but not that for IL-1beta, was drastically reduced in LPS-stimulated infected cells treated with Ag C10. Conceivably, inhibition of TNF-alpha and IL-12 by T. cruzi could be involved in the evasion of the immune response by this parasite. PMID- 9366424 TI - Cultured blood dendritic cells retain HIV-1 antigen-presenting capacity for memory CTL during progressive HIV-1 infection. AB - Dendritic cells (DC) are potent APC that may be involved in the pathogenesis of HIV-1 infection. We studied the APC function of DC from HIV-1-infected subjects that were derived from monocyte-depleted PBMC by culture in human IL-4 and human granulocyte-macrophage CSF. The cultured cells from the HIV-1-infected subjects had similar morphology and phenotype of mature DC (CD80 = 41 +/- 8%, CD86 = 77 +/ 5%, CD40 = 87 +/- 6%, CD1a = 1 +/- 1%) to DC cultured from seronegative subjects. The yield of these DC was lower than from HIV-1-seronegative subjects (4 +/- 0% vs 11 +/- 2%, p < 0.01), and the lower DC yields correlated with lower numbers of blood CD4+ T cells (r = 0.60, p < 0.01) and higher plasma viral load (r = -0.49, p < 0.01). DC from HIV-1-infected subjects were infected with recombinant vaccinia virus vectors expressing Gag, Pol, and Env and were able to stimulate equal or higher levels of MHC class I-restricted, anti-HIV-1 memory CTL (CTLm) than were similarly treated, autologous B lymphocyte cell lines. DC pulsed with peptides representing HIV-1 CTL epitopes stimulated higher levels of anti HIV-1 CTLm responses than did DC infected with the vaccinia virus-HIV-1 constructs. Allogeneic, MHC class I-matched DC also stimulated anti-HIV-1 CTLm activity in cells from HIV-1-infected subjects. DC from early and late stages of HIV-1 infection had a similar ability to activate CTLm specific for targets expressing either HIV-1 genes via vaccinia virus vectors or HIV-1 immunodominant synthetic peptides. However, DC from either early or late stages of HIV-1 infection could not overcome the defect in anti-HIV-1 CTLm response in advanced infection. PMID- 9366426 TI - Natural killer cell cytokine production, not cytotoxicity, contributes to resistance against blood-stage Plasmodium chabaudi AS infection. AB - Our recent study showed that IL-12 treatment of susceptible A/J mice induces Th1 mediated, protective immunity against lethal blood-stage Plasmodium chabaudi AS infection. To further understand the mechanism of this protection, we examined NK cell cytotoxic (NKCC) and cytokine secretory functions in untreated and IL-12 treated A/J mice, along with resistant C57BL/6 (B6) mice. Normal A/J mice receiving six daily doses of 0.1 microg IL-12 exhibited significant increases in NKCC in total spleen cell populations. Defective NKCC evident in vitro in enriched NK cells from infected A/J mice was corrected by addition of 10 ng/ml IL 12 and was comparable with that seen in B6 mice. In vivo and in vitro analyses revealed that enriched NK cells from day 6 infected A/J mice were defective not only in NKCC, but also in IFN-gamma, and to a certain extent, TNF-alpha secretion, which could also be corrected by IL-12 treatment. Depletion of NK cells from resistant B6 mice resulted in a more severe course of infection, while NK cell-depleted, IL-12-treated A/J mice had significantly higher parasitemia, as well as 100% mortality, suggesting the importance of NK cells in IL-12-mediated protection. NKCC-defective bg/bg mice produced optimum IFN-gamma and TNF-alpha and recovered from infection similar to bg/+ controls; in vivo depletion of these cytokines resulted in significantly higher parasitemia early in infection. Based on these results, we conclude that IFN-gamma, and possibly TNF-alpha, secretion by NK cells during early infection plays a major role in protective immunity to blood-stage malaria. PMID- 9366427 TI - Costimulation provided by DNA immunization enhances antitumor immunity. AB - The interaction of the TCR with MHC class I-bound Ag is insufficient for the priming of CTL unless secondary costimulatory signals are provided. To ascertain the minimum elements required to activate an Ag-specific CTL response in vivo, we injected mice intradermally or i.m. with plasmid DNA encoding a MHC class I restricted peptide Ag (minigene) and different membrane-bound costimulatory ligands. The minigene-encoded epitope only primed a specific CTL response if injected in the vicinity of an ectopically expressed costimulatory ligand. Vector encoding B7-1 was repeatedly more potent at stimulating a cytolytic response than vector encoding B7-2. In contrast the B7-2-encoding plasmid preferentially enhanced Ag-specific Ab responses when injected with either protein or a cDNA expression vector. Gene vaccination with plasmids encoding OVA and B7-1, but not B7-2, prolonged survival in mice challenged with an OVA-transfected tumor. These results show that functional B7-1 transfection can be achieved in vivo and induces the selective induction of CTL. The data suggest that B7-1 plasmids should be coadministered with naked DNA vaccines that aim to induce tumor specific cellular immunity. PMID- 9366428 TI - SCID mice reconstituted with IL-4-deficient lymphocytes, but not immunocompetent lymphocytes, are resistant to cutaneous leishmaniasis. AB - To characterize the roles of lymphoid- and non-lymphoid-derived IL-4 during cutaneous infection with Leishmania mexicana, the disease was monitored in SCID mice reconstituted with splenocytes from either immunocompetent BALB/c mice or IL 4-deficient BALB/c mice. Whereas following s.c. infection with L. mexicana no lesion growth was observed in BALB/c IL-4(-/-) mice and lesion growth was significantly inhibited in SCID mice, rapid initial lesion growth occurred in both SCID IL-4(+/+) and SCID IL-4(-/-) reconstituted mice. However, after 3 to 4 wk of infection, lesions in SCID IL-4(-/-) but not SCID IL-4(+/+) reconstituted mice began to heal. This paralleled a developing Th1-like phenotype and parasite clearance in the former group and a developing Th2-like phenotype in the latter group. Lesion sites from the healing SCID IL-4(-/-) mice expressed the inducible nitric oxide synthase, whereas the SCID IL-4(+/+) mice with progressive disease did not. These findings indicate that non-lymphocyte-derived IL-4 may play a role in initiating lesion growth following cutaneous infection with L. mexicana, but the presence of lymphocyte-derived IL-4 is essential for disease progression, and in its absence, lesions heal due to a developing Th1 phenotype. PMID- 9366429 TI - Analysis of granuloma formation in double cytokine-deficient mice reveals a central role for IL-10 in polarizing both T helper cell 1- and T helper cell 2 type cytokine responses in vivo. AB - In response to i.v.-injected eggs of Schistosoma mansoni, normal mice develop a dominant type 2 response, whereas IL-10-deficient animals generate a mixed type 1/type 2 cytokine profile and show reduced pulmonary granuloma formation. IL-4 deficient mice, while displaying diminished type 2 responses and granulomatous inflammation, also do not fully default to a type 1 cytokine profile. Strikingly, mice doubly deficient in IL-4 and IL-10 are completely defective in pulmonary granuloma formation and develop a highly polarized type 1 cytokine pattern. In analogous fashion, mice deficient in both IL-12 and IL-10 generate highly exacerbated type 2 cytokine responses, whereas in wild-type animals, IL-12 depletion minimally effects egg-induced cytokine production. Together, these results argue first that IL-10 is an important endogenous down-regulator of type 2 as well as type 1 cytokine synthesis, and second, that its induction is critical for type 2 response polarization in vivo. PMID- 9366430 TI - Leishmania major-infected C3H mice treated with anti-IL-12 mAb develop but do not maintain a Th2 response. AB - Leishmania major-infected C3H mice develop a Th1 response, but studies have shown that treatment of C3H mice with anti-IL-12 or anti-IFN-gamma mAb promotes the development of a Th2 response and susceptibility. However, we discovered that C3H mice treated for 3 wk with either anti-IL-12 or anti-IFN-gamma mAb eventually resolved their lesions and switched from a Th2 to a Th1 response. No significant differences in IL-4, IL-10, or IFN-gamma levels or in the parasite burden could be detected between BALB/c and anti-IL-12-treated C3H mice early after infection, suggesting that the instability of the Th2 response in anti-IL-12-treated C3H mice was unrelated to levels of these cytokines and parasite numbers. However, anti-IL-12-treated C3H mice continued to produce IL-12 in spite of exhibiting a Th2 phenotype. To determine whether the production of IL-12 was associated with the healing observed in these animals, we treated C3H mice with anti-IL-12 continuously for 12 wk. In contrast to C3H mice given anti-IL-12 for 3 wk, C3H mice continuously treated with anti-IL-12 failed to heal. These results suggest that qualitative differences in Th2-type responses may influence their stability and that the presence of IL-4, IL-10, or high parasite numbers is not sufficient to maintain a Th2 response in mice with certain genetic backgrounds. PMID- 9366431 TI - Treatment of a newly established transgenic model of chronic arthritis with nondepleting anti-CD4 monoclonal antibody. AB - We established a novel animal model for rheumatoid arthritis (RA) by following backcrossing to DBA/1 of (SWR/J x DBA/1)F1 TCR-beta Tg mice, previously reported to be highly susceptible to collagen-induced arthritis. These mice evolved, upon collagen type II immunization, into a chronic arthritis that histopathologically resembles RA. The availability of such a model prompted us to study the role of CD4+ T cells throughout the evolution of disease. Here, we show that administration of nondepleting anti-CD4 not only prevented the evolution of disease but also treated established arthritis. Moreover, functional analyses of T cells isolated from anti-CD4-treated mice demonstrated that the mechanism of protection is not achieved by suppression of the Th1 population but is mediated by induction of collagen type II-specific T cell anergy. Our study suggests that: 1) CD4+ T cells have a fundamental role both in the induction and in the perpetuation of disease; 2) targeting T cells may be an appropriate therapeutic option; and 3) a suitable and well-balanced anti-CD4 treatment may be a valid approach to the control of RA. PMID- 9366432 TI - Hamycin inhibits IL-8-induced biologic response by modulating its receptor in human polymorphonuclear neutrophils. AB - IL-8, a neutrophil chemotactic agent, is involved in a large number of neutrophil driven acute and chronic inflammatory diseases. We have found that hamycin, an antifungal agent, reduces IL-8-induced migration and binding of 125I-labeled IL-8 to neutrophils by 66 and 75%, respectively. Other IL-8-induced biologic functions, such as superoxide generation, intracellular Ca2+ mobilization, and enzyme release were also reduced in hamycin-treated cells by 50 to 75%. Anti-IL 8R Ab (C-X-CR1) and IL-8 itself failed to protect the cells from the effect of hamycin. Scatchard analysis of IL-8 binding data demonstrated that while the normal cells expressed 23,000 +/- 1,704 receptors/cell (Kd = 3.5 nM), the number was reduced to 8,000 +/- 592 receptors/cell (Kd = 3.43 nM) in hamycin-treated cells. Chemical cross-linking of 125I-labeled IL-8 to its receptor followed by 10% SDS-PAGE analysis and autoradiography showed that the signals in hamycin treated cells were considerably reduced compared with those in controls. In the immunoblot, however, the signals in control and hamycin-treated cells were almost identical. The intensity of the fluorescence emission of diphenyl hexatriene at 430 nm and membrane microviscosity measured by diphenyl hexatriene were considerably reduced in hamycin-treated cells, resulting in a reduced number of functional IL-8R, presumably by conformational change in the receptor. The study suggests that hamycin may be a potent immunomodulator of the IL-8R for alleviation of inflammatory distress. PMID- 9366433 TI - Lymphocytes mediate TNF-alpha-induced endothelial cell adhesion molecule expression: studies on SCID and RAG-1 mutant mice. AB - TNF-alpha is known to elicit a rapid increase in the expression of specific endothelial cell adhesion molecules (ECAMs) within different vascular beds. The aim of this study was to determine whether lymphocytes contribute to the increased ECAM expression elicited by TNF-alpha. A dual radiolabeled mAb technique was used to quantify constitutive and TNF-alpha-induced expression of ICAM-1, VCAM-1, E-selectin, and P-selectin in different vascular beds (lung, heart, stomach, mesentery, small intestine, large intestine, and muscle) in wild type and SCID mice. In reconstitution experiments, either whole splenocytes, T cell-enriched splenocytes, or B cell-enriched splenocytes were injected into SCID mice 48 h before TNF-alpha administration. Although the constitutive expression of ECAMs differed only slightly between wild-type and SCID mice, TNF-alpha induced ECAM expression was markedly blunted in SCID mice compared with wild-type mice. This blunted response to TNF-alpha was also demonstrated for VCAM-1 in recombination activating gene (RAG)-1 mutant mice. Reconstitution studies revealed that administration of 50 x 10(6) splenocytes in SCID mice at 48 h before cytokine treatment restored the TNF-alpha-induced expression of VCAM-1 to levels normally observed in wild-type mice. Reconstitution with T cell- but not B cell-enriched splenocytes, also restored the TNF-alpha-induced expression of VCAM 1 in SCID mice to wild-type levels. These results implicate circulating T lymphocytes as modulators of the increased ECAM expression elicited by TNF-alpha. PMID- 9366434 TI - Macrophage inflammatory protein-1 alpha production in lipopolysaccharide stimulated human adherent blood mononuclear cells is inhibited by the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine. AB - The release of chemokines such as macrophage-inflammatory protein-1 alpha (MIP-1 alpha) from activated macrophages is a crucial step in cell recruitment necessary for establishing local inflammatory responses. To ascertain the importance of the L-arginine/nitric oxide (NO) pathway in LPS-induced MIP-1 alpha release, we stimulated human adherent PBMC with LPS in the presence of the NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA). L-NMMA decreased LPS-induced MIP-1 alpha protein release (45.5% inhibition) and steady state levels of mRNA (48% inhibition) in adherent PBMC. The concentration of L-NMMA for inhibition of MIP-1 alpha release was dependent on the concentration of L-arginine in the cell culture medium, emphasizing the L-arginine-related action of the drug. Most of the MIP-1 alpha release was attributed to the activity of IL-1 and TNF, since coincubation of LPS-stimulated PBMC with IL-1R antagonist and TNF-binding protein abrogated LPS-induced MIP-1 alpha release (by 76.8%). Analysis of cytokine secretion revealed that, in addition to MIP-1 alpha, L-NMMA inhibited the release of mature IL-1 beta (by 70%) and TNF-alpha (by 53%). In contrast, release of macrophage chemoattractant protein-1 was unaffected; IL-10 was augmented (123.4%) by L-NMMA. In the presence of exogenous NO provided by NO donors, LPS-induced MIP 1 alpha release was enhanced. We concluded that endogenous NO acts as a mediator of inflammation. Since IL-10 is a potent anti-inflammatory cytokine, these data also suggest that L-NMMA acts as an anti-inflammatory agent by specifically altering the balance of pro- and anti-inflammatory cytokines released from LPS stimulated human PBMC. PMID- 9366435 TI - Formyl peptide receptors are coupled to multiple mitogen-activated protein kinase cascades by distinct signal transduction pathways: role in activation of reduced nicotinamide adenine dinucleotide oxidase. AB - Formyl peptide receptor activation of three mitogen-activated protein kinase (MAPK) cascades, extracellular signal-regulated kinases (ERKs), N-terminal kinases (JNKs), and p38 MAPK was examined in differentiated HL-60 granulocytes. FMLP stimulated a concentration- and time-dependent increase in ERK, JNK, and p38 MAPK activities, all of which were dependent on a pertussis toxin-sensitive G protein. Pharmacologic inhibitors were used to examine the roles of tyrosine kinases, phosphatidylinositol 3-kinase, protein kinase C, and phospholipase C. FMLP-stimulated ERK activity was dependent on tyrosine kinases, phosphatidylinositol 3-kinase, protein kinase C, and phospholipase C; p38 MAPK activation was dependent on phosphatidylinositol 3-kinase and phospholipase C; while JNK activation was independent of all of these signaling components. The mitogen-activated protein kinase/ERK kinase inhibitor PD098059 reduced ERK activation by 90%, while an inhibitor of p38 MAPK, SB203580, inhibited p38 MAPK activation by 80%. Both PD098059 and SB203580 inhibited FMLP-stimulated superoxide release, as did inhibitors directed against protein kinase C, tyrosine kinases, and phosphatidylinositol 3-kinase. We conclude that formyl peptide receptors are coupled to three MAPK cascades by Gi proteins. ERKs, p38 MAPK, and JNKs are each activated by distinct proximal signal transduction pathways. Activation of p38 MAPK is necessary for FMLP stimulation of respiratory burst activity; however, a second signal that may involve ERK is also required for this activity. PMID- 9366436 TI - Two functionally independent pathways for lipopolysaccharide-dependent activation of mouse peritoneal macrophages. AB - We have investigated the effects of human LPS-binding protein (LBP) and human bactericidal/permeability-increasing protein (BPI) on LPS-dependent activation of mouse thioglycolate-elicited peritoneal macrophages in vitro, in comparison with human PBMCs. Confirming earlier published studies, BPI inhibited, and LBP enhanced, the ability of LPS to stimulate PBMC production of the cytokines TNF alpha and IL-6. In marked contrast to these results, under identical conditions of in vitro culture, both LBP and BPI suppressed, in a dose-dependent manner, the ability of LPS to stimulate cytokine production in mouse macrophages. Further, while human BPI also suppressed LPS-dependent NO secretion in mouse macrophages, human LBP had no inhibitory effect on NO secretion under conditions that inhibited TNF-alpha secretion. These data provide the first direct evidence that mouse macrophages may utilize two independent pathways in response to LPS, thus leading to different phenotypic responses. PMID- 9366437 TI - Mechanical deformation promotes secretion of IL-1 alpha and IL-1 receptor antagonist. AB - Both IL-1 alpha and IL-1 beta lack an N terminus secretory sequence, and the mechanism of secretion of these pleiotropic cytokines is incompletely understood. The epidermis contains large quantities of IL-1 alpha in keratinocytes, which may play a role in inducing endothelial adhesion molecules and promoting extravasation of leukocytes. Here we report that mechanical deformation of human keratinocytes leads to rapid release of IL-1 alpha, possibly through transient disruptions in the plasma membrane. Using a device that precisely controls the amplitude of strain on the culture substrate, we found by pulse-chase analysis, Western analysis, and ELISA that the release of IL-1 alpha is dependent on the amplitude of the strain. A cyclic strain of 14% released a small but significant quantity of IL-1 alpha, while strains of 33% released 66 +/- 9% of cytoplasmic IL 1 alpha over 1 h (p < 0.001). Release of IL-1 alpha was accompanied by rapid release of large stores of IL-1R antagonist, approximately 25 to 30 times greater by mass than the quantity of IL-1 alpha released, but only a small fraction of cytoplasmic lactate dehydrogenase. Media conditioned by mechanically stimulated keratinocytes induced expression of E-selectin by human vascular endothelial cells; induction of E-selectin was completely inhibited by an Ab to IL-1 alpha. Therefore, mechanical strain promotes the secretion of IL-1 alpha, and deformation of keratinocytes in the epidermis may activate vascular endothelium through mechanically released IL-1 alpha. This pathophysiologic mechanism may play a role in the anatomic localization of some inflammatory skin diseases, such as psoriasis, which occurs more commonly in locations where the dermis is subjected to repetitive stretch or trauma. PMID- 9366438 TI - Lipocortin 1 protects against splanchnic artery occlusion and reperfusion injury by affecting neutrophil migration. AB - Splanchnic artery occlusion and reperfusion (SAO/R) shock was induced in rats by clamping both the superior mesenteric artery and the celiac trunk for 45 min, followed by release of the clamp (60-min reperfusion). Following this reperfusion period, rats developed a fall in mean arterial blood pressure, associated with a significant increase in tissue myeloperoxidase (MPO) activity in the intestine and a marked histologic injury to the distal ileum. Treatment of rats with a lipocortin-1 (LC1)-derived N-terminal peptide, peptide Ac(2-26), dose-dependently (0.125-0.5 mg/kg s.c.) reduced the progressive fall in blood pressure and prevented the infiltration of neutrophils into the reperfused intestine (reduced MPO activity). The LC1 peptide also reduced the degree of ischemia/reperfusion injury in the bowel as evaluated by histologic examination. The glucocorticoid dexamethasone (0.1 mg/kg s.c., -1 h) also produced a marked improvement in SAO/R shock (i.e., maintained mean arterial blood pressure and reduced tissue MPO activity), and this was reversed by pretreatment with two different antisera raised against the LC1 pharmacophore. Peptide Ac(2-26) (0.5 mg/kg s.c., -30 min) reduced (>60%) the extent of IL-1beta-induced cell emigration and significantly attenuated (approximately 45%) the number of adherent leukocytes in the rat mesenteric vascular bed, as assessed by video microscopy. These results suggest that LC1 inhibits neutrophil migration and accumulation into reperfused tissues, thereby ameliorating the outcome of SAO/R shock. PMID- 9366439 TI - Mercuric chloride-induced vasculitis in the Brown Norway rat: alpha beta T cell dependent and -independent phases: role of the mast cell. AB - Mercuric chloride induces a necrotizing vasculitis in the Brown Norway (BN) rat. This occurs in two phases, between 1 and 5 days (early) and between 12 and 20 days (late) after initiation of HgCl2. One outbred and four inbred rat strains were found to be susceptible to early vasculitis, but only the BN strain developed late vasculitis. In the BN strain, treatment with the mAb R73 (anti alpha beta TCR) inhibited T cell function, completely prevented the late vasculitis, but had no effect against early vasculitis, indicating that early and late vasculitis is controlled by different genetic and cellular mechanisms. The role of the mast cell in the alpha beta T cell-independent early phase was studied. Serum concentrations of rat mast cell protease II rose following HgCl2 treatment, indicating mast cell degranulation. The reagents Doxantrazole and the mAb G63, which suppress mast cell secretory responses, also prevented the rise in rat mast cell protease II and significantly reduced the early vasculitis. The demonstration of an alpha beta T cell-dependent phase supports previous experimental data that T cells play an important role in the pathogenesis of vasculitis. The presence of an earlier alpha beta T cell-independent phase is a unique observation. The data support a role for the mast cell in the early vasculitis. PMID- 9366440 TI - Inhibitory effects of chronic ethanol consumption on cellular immune responses to hepatitis C virus core protein are reversed by genetic immunizations augmented with cytokine-expressing plasmids. AB - Chronic hepatitis C viral (HCV) infection is a major clinical problem in alcoholics with liver disease and may result from ethanol effects on the host immune response. To experimentally assess such effects, the DNA-based immunization approach was used to produce humoral and cellular immune responses against the HCV core protein in mice. Mice were fed an ethanol or isocaloric pair fed control liquid diet followed by immunizations with HCV core DNA-expressing constructs. Chronic ethanol feeding was found to inhibit Th cell and CTL activities and substantially reduced cytokine secretion as well. In addition, a switch from Th1 to Th0 subtype was observed in proliferating CD4+ T cells derived from chronic ethanol-fed mice. These immunosuppressive effects were directly due to ethanol since crossover experiments to an isocaloric control diet restored the defects in cellular immunity. Furthermore, we determined if coadministration of an IL-2 or GM-CSF DNA expression plasmid with a plasmid expressing the HCV core protein (pHCV2-2) would reverse the inhibitory effects of chronic ethanol feeding on cellular immune responses. Coimmunization of chronic ethanol-fed mice with either IL-2 or GM-CSF expression plasmids restored cellular immunity and induced CD4+ inflammatory T cell and CD8+ CTL responses comparable with control mice immunized with pHCV2-2 alone. These studies provide evidence of how chronic ethanol feeding may effect cellular immune responses to a viral structural protein in the context of genetic immunization. PMID- 9366441 TI - Human monoclonal antibodies to the V3 loop of HIV-1 with intra- and interclade cross-reactivity. AB - Five human anti-V3 mAbs were generated from Ab-producing cells derived from the blood of HIV-1-infected individuals from North America and selected using the V3 peptide of a divergent clade B isolate, HIV(RF). The anti-V3(RF) mAbs were mapped to a cluster of three overlapping epitopes present in the KSITKGP sequence located in the hypervariable region on the N-terminal side of the V3 loop. Broad immunochemical cross-reactivity was noted when the mAbs were tested for binding to V3 peptides derived from four clade A viruses, nine clade B viruses, and two clade C viruses. These results demonstrate antigenic relatedness in the V3 regions of these three HIV-1 clades. Affinities determined by surface plasmon resonance were higher for recombinant gp120 than for V3 peptides, suggesting that these mAbs recognize both linear and conformationally dependent epitopes of the V3 loop. Two of the mAbs neutralized four clade B T cell line-adapted and primary isolates with varying degrees of potency. The two neutralizing mAbs were the most cross-reactive with V3 peptides from several clades, had the highest affinity for V3(RF) and V3(MN), and stained HIV-infected cells. The data suggest that cross reactivity, affinity, cell surface staining, and neutralizing activity are characteristics that describe an optimal fit between Ag and Ab. The results also demonstrate that the V3 peptides representing the sequence of several clade A, B, and C viruses share antigenic features that are recognized by the human immune response, a finding that suggests that cross-clade immunity to HIV-1 may be inducible by HIV-1 vaccines. PMID- 9366442 TI - CD28 costimulation increases CD8+ cell suppression of HIV replication. AB - A subset of CD8+ T lymphocytes that expresses CD28, a membrane receptor for B7 differentiation Ags found on APCs, is primarily responsible for the noncytotoxic suppression of HIV replication in CD4+ cells of HIV-infected individuals. Optimal inhibition of HIV production by CD8+ cells occurs after triggering the CD28 molecule on the cells with anti-CD28 Abs during stimulation. Blocking the interaction of the CD28 and B7 molecules with a CTLA4Ig fusion protein abrogates the ability of autologous macrophages to enhance this CD8+ cell antiviral activity. This blocking effect can be reversed by treating the CD8+ cells with anti-CD28 Ab. The increase in antiviral activity following CD28 costimulation correlates with enhanced IL-2 production and IL-2R expression by CD8+ cells. Prevention of IL-2 binding to its receptor, using anti-IL-2 or anti-IL-2R Abs, reduces the ability of CD8+ cells to suppress HIV replication following CD28 costimulation. Importantly, engagement of the CD28 molecule during stimulation of CD8+ cells from individuals with AIDS restored the ability of their cells to suppress HIV replication. Thus, triggering the CD28 molecule during stimulation of CD8+ cells could clinically benefit HIV-infected symptomatic patients. PMID- 9366444 TI - T cell clonality in synovial fluid of a patient with rheumatoid arthritis: persistent but fluctuant oligoclonal T cell expansions. AB - Recently, oligoclonal T cell accumulation has been reported in affected joints of patients with rheumatoid arthritis. To characterize such clonally accumulating T cells, we quantitatively monitored their frequency by analyzing TCR B chains. As a result, despite a similar TCR BV usage between synovial fluid (SF) and PBL, obviously skewed TCR BJ usage was detected in SF. Subsequent DNA sequencing demonstrated that the skewed BJ gene usage in SF resulted from clonal T cell accumulation. The complementarity-determining region 3 of TCR B chains of the detected clones appeared to have homologous amino acid sequences. Further, one of the predominant TCR B chains of the clones was identical with that reported previously. In the follow-up study, most of the accumulated clones persisted; however, in some, proportions were drastically decreased or increased during the time course. In particular, one of the clones expanded sixfold, from 11 to 67%, in the BV8-BJ2S3 TCR population of SF, even though the clone was not detected in PBL. In summary, oligoclonal T cell accumulation in SF was persistent, but it appeared to fluctuate independently of the clonality in PBL. The expansion of the clones in SF may occur by antigenic stimuli within the joint. PMID- 9366443 TI - Nitric oxide accelerates the onset and increases the severity of experimental autoimmune uveoretinitis through an IFN-gamma-dependent mechanism. AB - The production of large amounts of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) has been described as a double-edged sword eliciting pro- or anti inflammatory effects in different immune situations. Our aim, therefore, was to investigate its role in experimental autoimmune uveoretinitis (EAU), a model of ocular inflammation, induced in the Lewis rat following a single footpad injection of retinal Ags. iNOS enzyme was not detected in the normal Lewis rat eye, but was strongly expressed by infiltrating ED1+ macrophages during the acute inflammatory stages of EAU. Treating immunized animals with L-arginine increased urinary NO metabolite (NOx) levels, accelerated the inflammatory response, and increased disease severity, whereas treatment with the NOS inhibitor, N(G)-nitro L-arginine methyl ester, reduced NOx excretion, delayed the onset, and reduced the clinical signs of EAU. Reverse transcription-PCR analysis of ocular tissue from untreated and treated animals detected iNOS mRNA at all stages of disease, and expression was up-regulated during peak disease. L-arginine treatment enhanced cytokine mRNA expression, particularly of IFN-gamma, which was detected earlier than in control animals, corresponding with the more rapid onset of disease and increased disease severity observed in this group. N(G)-nitro-L arginine methyl ester had little or no effect on iNOS or inflammatory cytokine mRNA expression. These results suggest NO is central to the pathogenesis of EAU and highlight the importance of the macrophage as an effector cell in what is considered a CD4+ T cell-dependent disease. Furthermore, this study demonstrates the therapeutic potential of NOS inhibitors in the treatment of inflammatory and autoimmune mediated disease. PMID- 9366445 TI - Recombinant T cell receptor molecules can prevent and reverse experimental autoimmune encephalomyelitis: dose effects and involvement of both CD4 and CD8 T cells. AB - Autoimmune diseases are often characterized by spontaneous remission followed by relapses. Although the mechanism(s) controlling pathogenic self-reactive T cells are not fully understood, recent data in experimental autoimmune encephalomyelitis (EAE), a prototype for CD4 T cell-mediated autoimmune diseases, indicate that spontaneous recovery is mediated by regulatory T cells (Treg) specific for peptides derived from the beta-chain of the TCR. Here we have tested whether recombinant single-chain TCRs (scTCRs) containing Vbeta domains can be used as vaccines for efficient priming of Treg. A single injection of mice with these recombinant proteins leads to efficient in vivo priming of Treg and almost complete protection from Ag-induced EAE. Significantly, administration of scTCRs during ongoing disease at a 10-fold lower dose than that required for prophylactic treatment also reverses established EAE. However, if a higher dose of scTCR is administered during ongoing disease, paralytic symptoms become exacerbated and the majority of treated animals die from severe and chronic EAE. Furthermore, we demonstrate that regulatory determinants are processed and presented from scTCRs resulting in the recruitment of both CD4 and CD8 regulatory T cells which are required for efficient regulation induced by scTCR. Reversal of established disease following an optimum dose of recombinant TCRs suggests that proteins expressing appropriate Vbeta domains could be used for the treatment of a variety of T cell-mediated pathologic conditions. PMID- 9366446 TI - Inhibition of IL-12 production by thalidomide. AB - The immunomodulatory properties of thalidomide are currently being exploited therapeutically in conditions as diverse as erythema nodosum leprosum, chronic graft-vs-host disease, rheumatoid arthritis, and sarcoidosis. The relevant mechanism of action of thalidomide in these diseases remains unclear. The important role recently ascribed to IL-12, a cytokine critical to the development of cellular immune responses, in the pathogenesis of several of these conditions led us to examine whether thalidomide affects the production of IL-12. Thalidomide potently suppressed the production of IL-12 from human PBMC and primary human monocytes in a concentration-dependent manner. Thalidomide-induced inhibition of IL-12 production was additive to that induced by suboptimal inhibiting doses of dexamethasone, and occurred by a mechanism independent of known endogenous inhibitors of IL-12 production. These results suggest that thalidomide may have therapeutic utility in a wide range of immunologic disorders that are characterized by inappropriate cellular immune responses. PMID- 9366447 TI - Comparison of HIV-1 envelope-specific CD4+ T cell lines simultaneously established from peripheral blood mononuclear cells and lymph node biopsy in HIV 1-infected individuals. AB - HIV-1 envelope-specific CD4+ T cell lines were established simultaneously from PBMC and lymph node mononuclear cells of two HIV-1-infected patients. Three recombinant envelope proteins were used to establish the CD4+ T cell lines: gp160NL4-3, gp120IIIB, and gp120MN. Six T cell lines were established from the first patient, one for each Ag from each compartment, and four T cell lines, two per compartment, were established from the second patient. Each line was challenged with a panel of overlapping peptides spanning the entire gp120 sequence to define its T cell epitope specificity. The pattern of recognition for all the lines from any given patient was similar between compartments. Each patient had a different pattern of peptide recognition. TCR analysis showed a heterogeneous usage of Vbeta between lines with same peptide specificity and established from different compartments. These data suggest that the cellular immune response does not phenotypically vary between the peripheral blood and lymph node compartments, but demonstrates genotypic heterogeneity, showing possible redundancy of the immune response to HIV-1 gp160. PMID- 9366449 TI - Surrogate endpoints and neuromuscular recovery. PMID- 9366448 TI - Prevention of immunotoxin-induced immunogenicity by coadministration with CTLA4Ig enhances antitumor efficacy. AB - Immunotoxins have shown promise as antitumor agents in clinical trials. However, they have not become part of standard cancer therapy because of factors that include their inherent immunogenicity, which limits the duration of therapy. To address this issue, we evaluated in preclinical models the concomitant use of the immunosuppressive agent CTLA4Ig and BR96 sFv-PE40, a single-chain immunotoxin that binds to carcinoma cells expressing Le(y). Cotreatment with CTLA4Ig, an inhibitor of the CD28/CTLA4-CD80/CD86 costimulation pathway, blocked the production of Abs against BR96 sFv-PE40 in immunocompetent rodents and dogs. It also blocked hypersensitivity reactions in rats carrying colon carcinoma allografts during a second course of BR96 sFv-PE40 therapy, and the cotreatment with CTLA4Ig resulted in enhanced antitumor activity. Cotreatment with CTLA4Ig also prevented hypersensitivity reactions induced by repeat dosing of BR96 sFv PE40 (q3dx5) in dogs. The production of anti-BR96-sFv-PE40 Abs was decreased in CTLA4Ig-cotreated rodents and dogs resulting in increased plasma levels of BR96 sFv-PE40 relative to non-CTLA4Ig-cotreated animals. These data show that cotreatment of immunotoxins with CTLA4Ig, by inhibiting the production of anti immunotoxin Abs, can extend the duration of BR96 sFv-PE40 therapy to give greater exposure, reduced toxicities, and increased efficacy. PMID- 9366450 TI - Application of practice guidelines to anesthesiology. PMID- 9366451 TI - "Exciting" aspects of opiate receptor signal transduction. PMID- 9366452 TI - Why does insensitivity to opioid narcotics develop? PMID- 9366453 TI - Functional assessment of the pharynx at rest and during swallowing in partially paralyzed humans: simultaneous videomanometry and mechanomyography of awake human volunteers. AB - BACKGROUND: Functional characteristics of the pharynx and upper esophagus, including aspiration episodes, were investigated in 14 awake volunteers during various levels of partial neuromuscular block. Pharyngeal function was evaluated using videoradiography and computerized pharyngeal manometry during contrast bolus swallowing. METHODS: Measurements of pharyngeal constrictor muscle function (contraction amplitude, duration, and slope), upper esophageal sphincter muscle resting tone, muscle coordination, bolus transit time, and aspiration under fluoroscopic control (laryngeal or tracheal penetration) were made before (control measurements) and during a vecuronium-induced partial neuromuscular paralysis, at fixed intervals of mechanical adductor pollicis muscle train-of four (TOF) fade; that is, at TOF ratios of 0.60, 0.70, 0.80, and after recovery to a TOF ratio > 0.90. RESULTS: Six volunteers aspirated (laryngeal penetration) at a TOF ratio < 0.90. None of them aspirated at a TOF ratio > 0.90 or during control recording. Pharyngeal constrictor muscle function was not affected at any level of paralysis. The upper esophageal sphincter resting tone was significantly reduced at TOF ratios of 0.60, 0.70, and 0.80 (P < 0.05). This was associated with reduced muscle coordination and shortened bolus transit time at a TOF ratio of 0.60. CONCLUSIONS: Vecuronium-induced partial paralysis cause pharyngeal dysfunction and increased risk for aspiration at mechanical adductor pollicis TOF ratios < 0.90. Pharyngeal function is not normalized until an adductor pollicis TOF ratio of > 0.90 is reached. The upper esophageal sphincter muscle is more sensitive to vecuronium than is the pharyngeal constrictor muscle. PMID- 9366454 TI - Cost-effective reduction of neuromuscular-blocking drug expenditures. AB - BACKGROUND: Anesthetic drug expenditures have been a focus of cost-containment efforts. The aim of this study was to determine whether expenditures for neuromuscular-blocking agents could be reduced without compromising outcome, and to determine whether such a cost-effective pattern of neuromuscular blocker use could be sustained. METHODS: Education, practice guidelines, and paperwork barriers were used to persuade anesthesiologists to substitute low-cost neuromuscular-blocking drugs (pancuronium or a metocurine-pancuronium combination) for a more costly neuromuscular-blocking drug (vecuronium). Neuromuscular-blocking drug use in all patients during a historical control period (6 months; n = 4,804) was compared with that during two consecutive 1-yr periods of intervention (n = 9,761/n = 10,695). Expenditures for vecuronium and for all neuromuscular-blocking drugs were compared for the control and intervention periods. The rate of complications related to neuromuscular-blocking drugs was determined by an ongoing continuous quality improvement program. RESULTS: Vecuronium use decreased by 76% during the first and second yr of intervention, compared with the historical period (P < 0.01). The cost of neuromuscular-blocking drugs decreased by 31% (P < 0.01) and 47% (P < 0.01) for the first and second yr, respectively. The complication rate related to neuromuscular-blocking drugs was 0.081% in the historical period and 0.11% and 0.093% during the intervention periods (P = 0.29 and 0.41). CONCLUSION: Practice guidelines, education, and paperwork barriers used together substantially reduced the expenditures for neuromuscular-blocking drugs for 2 yr without adversely affecting clinical outcome. PMID- 9366455 TI - Spinal anesthesia speeds active postoperative rewarming. AB - BACKGROUND: Redistribution of body heat decreases core temperature more during general than regional anesthesia. However, the combination of anesthetic- and sedative-induced inhibition may prevent effective upper-body thermoregulatory responses even during regional anesthesia. The extent to which each type of anesthesia promotes hypothermia thus remains controversial. Accordingly, the authors evaluated intraoperative core hypothermia in patients assigned to receive spinal or general anesthesia. They also tested the hypothesis that the efficacy of active postoperative warming is augmented when spinal anesthesia maintains vasodilation. METHODS: Patients undergoing lower abdominal and leg surgery were randomly assigned to receive general anesthesia (isoflurane and nitrous oxide; n = 20) or spinal anesthesia (bupivacaine; n = 20). Fluids were warmed to 37 degrees C and patients were covered with surgical drapes. However, no other active warming was applied during operation. Ambient temperatures were maintained near 20 degrees C. After operation, patients were warmed with a full-length, forced-air cover set to 43 degrees C. Shivering, when observed, was treated with intravenous meperidine. RESULTS: The mean spinal analgesia level, which was at the sixth thoracic level during surgery, remained at the T12 dermatome after 90 min after operation. Core temperatures did not differ significantly during surgery and decreased to 34.4 +/- 0.5 degrees C and 34.1 +/- 0.4 degrees C, respectively, in patients given spinal and general anesthesia. After operation, however, core temperatures increased significantly faster (1.2 +/- 0.1 degrees C/h vs. 0.7 +/- 0.2 degrees C/h, mean +/- SD; P < 0.001) in patients given spinal anesthesia. Consequently, patients given spinal anesthesia required less time to rewarm to 36.5 degrees C (122 +/- 28 min vs. 199 +/- 28 min; P < 0.001). CONCLUSIONS: Comparable intraoperative hypothermia during general and regional anesthesia presumably resulted because the combination of spinal anesthesia and meperidine administration obliterated effective peripheral and central thermoregulatory control. Vasodilation increased the rate of core rewarming in patients after operation with residual lower-body sympathetic blocks, suggesting that vasoconstriction decreased peripheral-to-core heat transfer after general anesthesia. PMID- 9366456 TI - Pharyngeal patency in response to advancement of the mandible in obese anesthetized persons. AB - BACKGROUND: During anesthesia in humans, anterior displacement of the mandible is often helpful to relieve airway obstruction. However, it appears to be less useful in obese patients. The authors tested the possibility that obesity limits the effectiveness of the maneuver. METHODS: Total muscle paralysis was induced under general anesthesia in a group of obese persons (n = 9; body mass index, 32 +/- 3 kg[-2]) and in a group of nonobese persons (n = 9; body mas index, 21 +/- 2 kg[-2]). Nocturnal oximetry confirmed that none of them had sleep-disordered breathing. The cross-sectional area of the pharynx was measured endoscopically at different static airway pressures. A static pressure-area plot allowed assessment of the mechanical properties of the pharynx. The influence of mandibular advancement on airway patency was assessed by comparing the static pressure-area relation with and without the maneuver in obese and nonobese persons. RESULTS: Mandibular advancement increased the retroglossal area at a given pharyngeal pressure, and mandibular advancement increased the retropalatal area in nonobese but not in obese persons at a given pharyngeal pressure. CONCLUSION: Mandibular advancement did not improve the retropalatal airway in obese persons. PMID- 9366457 TI - Cerebral emboli during cardiac surgery in children. AB - BACKGROUND: Microemboli occur commonly during cardiac surgery in adults, and, when present, increase the risk of neuropsychological deficits. Their incidence and significance during correction of congenital heart disease is unknown. The authors hypothesized that microemboli would occur before bypass with right-to left cardiac shunts and would also occur in large numbers when the aortic crossclamp was released in children during repair of congenital heart defects. METHODS: In 25 children studied with carotid artery Doppler, embolic signals were counted and timed in relation to 13 intraoperative events. Patients were classified as either at high risk (obligate right-to-left shunt or uncorrected transposition of the great arteries) or at low risk (net left-to-right shunt or simple obstructive lesions) for paradoxical (venous to arterial) emboli. RESULTS: The median number of emboli detected was 122 (range, 2-2,664). Forty-two percent of all emboli were detected within 3 min of release of the aortic crossclamp. The high-risk group had significantly more emboli (median, 66; range, 0-116) during the time interval before cardiopulmonary bypass than did the low-risk group (median, 8; range, 0-73), with P < 0.01. There was no significant difference between the high- and low-risk groups in the total number of emboli detected. There was no apparent association between number of emboli and gross neurologic deficits. CONCLUSIONS: Microemboli can be detected in the carotid arteries of children undergoing repair of congenital heart disease and are especially prevalent immediately after release of the aortic crossclamp. The role of emboli in causing neurologic injury in children undergoing repair of congenital heart disease remains to be determined. PMID- 9366458 TI - Difficult or impossible ventilation after sufentanil-induced anesthesia is caused primarily by vocal cord closure. AB - INTRODUCTION: Opioid-induced rigidity often makes bag-mask ventilation difficult or impossible during induction of anesthesia. Difficult ventilation may result from chest wall rigidity, upper airway closure, or both. This study further defines the contribution of vocal cord closure to this phenomenon. METHODS: With institutional review board approval, 30 patients undergoing elective cardiac surgery participated in the study. Morphine (0.1 mg/kg) and scopolamine (6 microg/kg) given intramuscularly provided sedation along with intravenous midazolam as needed. Lidocaine 10% spray provided topical anesthesia of the oropharynx. A fiberoptic bronchoscope positioned in the airway photographed the glottis before induction of anesthesia A second photograph was obtained after induction with 3 microg/kg sufentanil administered during a period of 2 min. A mechanical ventilator provided 10 ml/kg breaths at 10/min via mask and oral airway with jaw thrust. A side-stream spirometer captured objective pulmonary compliance data. Subjective airway compliance was scored. Pancuronium (0.1 mg/kg) provided muscle relaxation. One minute after the muscle relaxant was given, a third photograph was taken and compliance measurements and scores were repeated. Photographs were scored in a random, blinded manner by one investigator. Wilcoxon signed rank tests compared groups, with Bonferroni correction. Differences were considered significant at P < 0.05. RESULTS: Twenty-eight of 30 patients exhibited decreased pulmonary compliance and closed vocal cords after opioid induction. Two patients with neither objective nor subjective changes in pulmonary compliance had open vocal cords after opioid administration. Both subjective and objective compliances increased from severely compromised values after narcotic-induced anesthesia to normal values (P = 0.000002) after patients received a relaxant. Photo scores document open cords before induction, progressing to closed cords after the opioid (P = 0.00002), and opening again after a relaxant was administered (P = 0.00005). CONCLUSION: Closure of vocal cords is the major cause of difficult ventilation after opioid-induced anesthesia. PMID- 9366459 TI - Opioid-sparing effects of a low-dose infusion of naloxone in patient-administered morphine sulfate. AB - BACKGROUND: A naloxone infusion is effective in reducing epidural and intrathecal opioid-related side effects. The use of naloxone infusion concomitant with intravenous morphine patient-controlled analgesia (PCA) has not been evaluated, probably because of an expected direct antagonism of the systemic opioid effect. The authors compared the incidence of morphine-related side effects and the quality of analgesia from two small doses of naloxone infusion. METHODS: Sixty patients classified as American Society of Anesthesiologists physical status 1, 2, or 3 who were scheduled for total abdominal hysterectomies were enrolled in the study. Patients received a standardized general anesthetic. In the postanesthetic care unit, patients received morphine as a PCA. They were randomized to receive either 0.25 microg x kg(-1) x h(-1) naloxone (low dose), 1 microg x kg(-1) x h(-1) (high dose), or saline (placebo) as a continuous infusion. Verbal rating scores for pain, nausea, vomiting, and pruritus; sedation scores; requests for antiemetic; and morphine use were recorded for 24 h. Blood pressure, respiratory rate, and oxyhemoglobin saturation were also monitored. RESULTS: Sixty patients completed the study. Both naloxone doses were equally effective in reducing the incidence of nausea, vomiting, and pruritus compared with placebo (P < 0.05 by the chi-squared test). There was no difference in the verbal rating scores for pain between the groups. The cumulative morphine use was the lowest in the low-dose group (42.3 +/- 24.1 mg; means +/- SD) compared with the placebo (59.1 +/- 27.4 mg) and high-dose groups (64.7 +/- 33.0 mg) at 24 h (P < 0.05 by analysis of variance). There was no incidence of respiratory depression (<8 breaths/min) and no difference in sedation scores, antiemetic use, respiratory rate, and hemodynamic parameters among the groups. CONCLUSIONS: Naloxone is effective in preventing PCA opioid-related side effects. Naloxone infusion at 0.25 microg x kg(-1) x h(-1) not only attenuates these side effects but appears to reduce postoperative (beyond 4-8 h) opioid requirements. This dosing regimen can be prepared with 400 microg naloxone in 1,000 ml crystalloid given in 24 h to a patient weighing 70 kg. PMID- 9366461 TI - Efficacy of intraoperative cooling methods. AB - BACKGROUND: Patients may require perioperative cooling for a variety of reasons including treatment of a malignant hyperthermia crisis and induction of therapeutic hypothermia for neurosurgery. The authors compared heat transfer and core cooling rates with five cooling methods. METHODS: Six healthy volunteers were anesthetized with desflurane and nitrous oxide. The cooling methods were 1) circulating water (5 degrees C, full-length mattress and cover), 2) forced air (10 degrees C, full-length cover), 3) gastric lavage (500 ml iced water every 10 min), 4) bladder lavage (300 ml iced Ringer's solution every 10 min), and 5) ice water immersion. Each method was applied for 40 min or until the volunteers' core temperatures approached 34 degrees C. The volunteers were rewarmed to normothermia between treatments. Core cooling rates were evaluated using linear regression. RESULTS: The first volunteer developed abdominal cramping and diarrhea after gastric lavage. Consequently, the technique was not again attempted. Bladder lavage increased heat loss approximately 10 W and decreased core temperature 0.8 +/- 0.3 degrees C/h (r2 = 0.99 +/- 0.002; means +/- SD). Forced-air and circulating-water cooling comparably increased heat flux, approximately 170 W. Consequently, core cooling rates were similar during the two treatments at 1.7 +/- 0.5 degrees C/h (r2 = 0.99 +/- 0.001) and 1.6 +/- 1.1 degrees C/h (r2 = 0.98 +/- 0.02), respectively. Immersion in an ice water slurry increased heat loss approximately 600-800 W and decreased core temperature 9.7 +/ 4.4 degrees C/h (r2 = 0.98 +/- 0.01). Immersion cooling was associated with an afterdrop of approximately 2 degrees C. CONCLUSIONS: Bladder lavage provided only trivial cooling and gastric lavage provoked complications. Forced-air and circulating-water cooling transferred relatively little heat but are noninvasive and easy to implement. Forced-air or circulating-water cooling, perhaps combined with intravenous administration of refrigerated fluids, may be sufficient in some patients. When noninvasive methods prove insufficient for rapid cooling, ice water immersion or peritoneal lavage probably should be the next lines of defense. PMID- 9366460 TI - Subjective, psychomotor, cognitive, and analgesic effects of subanesthetic concentrations of sevoflurane and nitrous oxide. AB - BACKGROUND: Sevoflurane is a volatile general anesthetic that differs in chemical nature from the gaseous anesthetic nitrous oxide. In a controlled laboratory setting, the authors characterized the subjective, psychomotor, and analgesic effects of sevoflurane and nitrous oxide at two equal minimum alveolar subanesthetic concentrations. METHODS: A crossover design was used to test the effects of two end-tidal concentrations of sevoflurane (0.3% and 0.60%), two end tidal concentrations of nitrous oxide (15% and 30%) that were equal in minimum alveolar concentration to that of sevoflurane, and placebo (100% oxygen) in 12 healthy volunteers. The volunteers inhaled one of these concentrations of sevoflurane, nitrous oxide, or placebo for 35 min. Dependent measures included subjective, psychomotor, and physiologic effects, and pain ratings measured during a cold-water test. RESULTS: Sevoflurane produced a greater degree of amnesia, psychomotor impairment, and drowsiness than did equal minimum alveolar concentrations of nitrous oxide. Recovery from sevoflurane and nitrous oxide effects was rapid. Nitrous oxide but not sevoflurane had analgesic effects. CONCLUSIONS: Sevoflurane and nitrous oxide produced different profiles of subjective, behavioral, and cognitive effects, with sevoflurane, in general, producing an overall greater magnitude of effect. The differences in effects between sevoflurane and nitrous oxide are consistent with the differences in their chemical nature and putative mechanisms of action. PMID- 9366462 TI - Bioavailability of intramuscular rocuronium in infants and children. AB - BACKGROUND: Intramuscular rocuronium, in doses of 1,000 microg/kg in infants and 1,800 microg/kg in children, produces complete twitch depression in 5-6 min. To determine the rate and extent of absorption of rocuronium after intramuscular administration, blood was sampled at various intervals after rocuronium administration by both intramuscular and intravenous routes to determine plasma concentrations (Cp) of rocuronium. METHODS: Twenty-nine pediatric patients ages 3 months to 5 yr were anesthetized with N2O and halothane. The trachea was intubated, ventilation was controlled, and adductor pollicis twitch tension was measured. When anesthetic conditions were stable, rocuronium (1,000 microg/kg for infants and 1,800 microg/kg for children) was injected either intramuscularly (in the deltoid muscle) or intravenously. Four venous plasma samples were obtained from each child 2-240 min after rocuronium administration. A mixed-effects population pharmacokinetic analysis was applied to these values to determine bioavailability, absorption rate constant, and time to peak Cp with intramuscular administration. RESULTS: With intramuscular administration, rocuronium's bioavailability averaged 82.6% and its absorption rate constant was 0.105 min( 1). Simulation indicated that Cp peaked 13 min after rocuronium was given intramuscularly, and that 30 min after intramuscular administration, less than 4% of the administered dose remained to be absorbed from the intramuscular depot. CONCLUSIONS: After rocuronium is administered into the deltoid muscle, plasma concentrations peak at 13 min, and approximately 80% of the administered drug is absorbed systemically. PMID- 9366463 TI - Midazolam changes cerebral blood flow in discrete brain regions: an H2(15)O positron emission tomography study. AB - BACKGROUND: Changes in regional cerebral blood flow (rCBF) determined with H2(15)O positron emission tomographic imaging can identify neural circuits affected by centrally acting drugs. METHODS: Fourteen volunteers received one of two midazolam infusions adjusted according to electroencephalographic response. Low or high midazolam effects were identified using post-hoc spectral analysis of the electroencephalographic response obtained during positron emission tomographic imaging based on the absence or presence of 14-Hz spindle activity. The absolute change in global CBF was calculated, and relative changes in rCBF were determined using statistical parametric mapping with localization to standard stereotactic coordinates. RESULTS: The low-effect group received 7.5 +/- 1.7 mg midazolam (serum concentrations, 74 +/- 24 ng/ml), and the high-effect group received 9.7 +/- 1.3 mg midazolam (serum concentrations, 129 +/- 48 ng/ml). Midazolam decreased global CBF by 12% from 39.2 +/- 4.1 to 34.4 +/- 6.1 ml x 100 g(-1) x min(-1) (P < 0.02 at a partial pressure of carbon dioxide of 40 mmHg). The rCBF changes in the low-effect group were a subset of the high-effect group. Decreased rCBF (P < 0.001) occurred in the insula, the cingulate gyrus, multiple areas in the prefrontal cortex, the thalamus, and parietal and temporal association areas. Asymmetric changes occurred, particularly in the low-effect group, and were more significant in the left frontal cortex and thalamus and the right insula. Relative rCBF was increased in the occipital areas. CONCLUSION: Midazolam causes dose-related changes in rCBF in brain regions associated with the normal functioning of arousal, attention, and memory. PMID- 9366464 TI - Opioid effects on mitogen-activated protein kinase signaling cascades. AB - BACKGROUND: The molecular mechanisms underlying both beneficial and undesirable opioid actions are poorly understood. Recently, the three currently known mammalian mitogen-activated protein kinase (MAPK) signaling cascades (extracellular signal-related kinase [ERK], stress-activated protein kinase, and p38 kinase) were shown to play important roles in transducing receptor-mediated signaling processes. METHODS: To determine whether any of these kinase cascades were activated by opioids, mu, delta, or kappa opioid receptors were transiently introduced into COS-7 cells together with MAPKs tagged to allow recognition by specific antibodies, and then exposed to opioids. Mitogen-activated protein kinase activation was determined by an in vitro MAPK activation assay. In addition, C6 glioma cells with either mu, delta, or kappa receptors stably introduced were exposed to opioids and MAPK activation determined by in vitro activation assay or antibody detection of activated forms. RESULTS: Transient experiments in COS cells revealed potent stimulation of ERK by mu and delta receptor activation, weak stimulation of stress-activated protein kinase by all receptor types, and no activation of p38. In stably transfected C6 glioma cells, only ERK activation was observed. Extracellular signal-related kinase induction was rapid, peaking 5 min after stimulation, and its activation was receptor-type specific. Mu and delta receptor stimulation activated ERK, but kappa stimulation did not. CONCLUSIONS: These results show that acute opioid signaling is not only inhibitory, but can strongly activate an important signaling cascade. Extracellular signal-related kinase activation may contribute to desirable responses to opioids, such as analgesia and sedation, and also to undesirable adaptive responses, such as tolerance, physical dependence, and possibly addiction. Further study of this system could provide greater insight into the molecular mechanisms underlying these clinical problems. PMID- 9366465 TI - Regulation of mu opioid receptor mRNA levels by activation of protein kinase C in human SH-SY5Y neuroblastoma cells. AB - BACKGROUND: The mu opioid receptor (MuOR) is a member of the superfamily of G protein-coupled receptors that mediates the analgesic actions of endogenous opioid peptides and the narcotic alkaloid derivatives of morphine. Activation and translocation of protein kinase C (PKC) by N-methyl-D-aspartate receptor stimulation correlates with resistance to opioid drugs in experimental states of neuropathic pain, but the cellular mechanisms of resistance have not been identified. One possibility is that PKC activation regulates MuOR mRNA expression and thus the ability to generate functional receptors. Using a human neuroblastoma cell line, the authors tested the hypothesis that phorbol ester activation of PKC regulates MuOR mRNA levels. METHODS: SH-SY5Y cells were maintained in a continuous monolayer culture and treated with phorbol esters or other agents before extraction of total cellular RNA. Slot-blot hybridization was used to measure the level of MuOR mRNA using 32P-labeled MuOR cDNA probes under high-stringency conditions. Autoradiograms were analyzed by scanning and densitometry. RESULTS: MuOR mRNA levels decreased in a dose- and time-dependent manner after tetradecanoyl phorbol acetate (TPA) was administered to activate PKC. The nadir, a level of approximately 50% of control, was at 2-8 h, followed by gradual recovery. The actions of TPA were blocked by pretreatment with the selective PKC inhibitor bisindolylmaleimide, but not by inhibition of protein synthesis with cycloheximide or anisomycin. The combination of TPA treatment and transcription inhibition with actinomycin D was associated with a transient increase in MuOR mRNA. CONCLUSIONS: Mu opioid receptor mRNA levels are regulated by activation of PKC in a neuronal model. Protein kinase C effects which decrease MuOR mRNA levels appear largely independent of new protein synthesis, and cytotoxicity does not account for the findings. Plasticity of MuOR gene expression may contribute to variations in clinical responses to opioid analgesics in clinical states such as neuropathic pain. PMID- 9366466 TI - Comparison of the effects of propofol and pentobarbital on neurologic outcome and cerebral infarct size after temporary focal ischemia in the rat. AB - BACKGROUND: Although propofol is known to have effects on cerebral physiology similar to the barbiturates, a direct comparison of the relative effects of these drugs on outcome from cerebral ischemia has not been performed. The authors postulated that pentobarbital or propofol would yield similar effects on neurologic and histologic outcome from temporary focal ischemia in the rat. METHODS: Wistar rats were anesthetized with sufficient doses of pentobarbital (n = 20) or propofol (n = 20) to cause electroencephalographic burst suppression. The middle cerebral artery was then occluded for 75 min. Animals were awakened 4 6 h after onset of reperfusion and allowed to recover for 1 week. Neurologic function and infarct size were then assessed. RESULTS: Relevant physiologic values were similar between groups during ischemia and early reperfusion. No difference between groups was observed for severity of hemiparesis (P = 0.10). Total cerebral infarct volumes (median +/- quartile deviation) were similar for the two groups (pentobarbital = 190 +/- 36 mm3; propofol = 200 +/- 24 mm3, P = 0.35). CONCLUSION: Neurologic and histologic outcome were similar in pentobarbital or propofol anesthetized rats undergoing temporary focal cerebral ischemia and a 1-week recovery interval. PMID- 9366467 TI - Effects of intrathecally administered nociceptin, an opioid receptor-like1 receptor agonist, and N-methyl-D-aspartate receptor antagonists on the thermal hyperalgesia induced by partial sciatic nerve injury in the rat. AB - BACKGROUND: Nociceptin is a 17-amino acid peptide and acts as a potent endogenous agonist of the opioid receptor-like1 receptor. Nociceptin is reported to depress glutamatergic transmission and to block the spinal facilitation that is thought to be mediated by the N-methyl-D-aspartate (NMDA) receptor. In the present study, the authors investigated the effect of intrathecally administered nociceptin and NMDA antagonists on the level of thermal hyperalgesia after partial sciatic nerve injury in the rat. METHODS: Partial sciatic nerve injury was created by tight ligation of one third to one half of the right sciatic nerve. The level of thermal hyperalgesia was evaluated by the difference score, which was calculated by subtracting the paw withdrawal latency against thermal nociceptive stimulation in the uninjured paw from that in the injured paw. Drugs were administered intrathecally 7 or 11 days after the nerve injury, and the level of thermal hyperalgesia was measured 5, 15, 30, 60, and 90 min after the drug injection. RESULTS: Intrathecal injection of nociceptin, but not of NMDA antagonists, attenuated the level of thermal hyperalgesia in a dose-dependent manner at a dose of 0.17-17 nM (post-drug difference score: saline-treated rats, -4.9 +/- 2.2 s; 17 nM nociceptin-treated rats, -1.3 +/- 0.9 s). CONCLUSIONS: Intrathecal injection of nociceptin attenuated the level of thermal hyperalgesia induced by partial sciatic nerve injury, and NMDA receptor-dependent spinal facilitation does not play an important role in maintaining thermal hyperalgesia in rats with partial sciatic nerve injury. PMID- 9366468 TI - Atelectasis is a major cause of hypoxemia and shunt after cardiopulmonary bypass: an experimental study. AB - BACKGROUND: Respiratory failure after cardiopulmonary bypass (CPB) remains a major complication after cardiac surgery. The authors tested the hypothesis that atelectasis is an important factor responsible for the increase in intrapulmonary shunt after CPB. METHODS: Six pigs received standard CPB (bypass group). Six other pigs had the same surgery but without CPB (sternotomy group). Another six pigs were anesthetized for the same duration but without any surgery (control group). The ventilation-perfusion distribution was measured with the inert gases technique, extravascular lung water was quantified by the double-indicator distribution technique, and atelectasis was analyzed by computed tomography. RESULTS: Intrapulmonary shunt increased markedly after bypass but was unchanged over time in the control group (17.9 +/- 6.2% vs. 3.5 +/- 1.2%; P < 0.0001). Shunt also increased in the sternotomy group (10 +/- 2.6%; P < 0.01 compared with baseline) but was significantly lower than in the bypass group (P < 0.01). Extravascular lung water was not significantly altered in any group. The pigs in the bypass group showed extensive atelectasis (32.3 +/- 28.7%), which was significantly larger than in the two other groups. The pigs in the sternotomy group showed less atelectasis (4.1 +/- 1.9%) but still more (P < 0.05) than the controls (1.1 +/- 1.6%). There was good correlation between shunt and atelectasis when all data were pooled (R2 = 0.67; P < 0.0001). CONCLUSIONS: Atelectasis is produced to a much larger extent after CPB than after anesthesia alone or with sternotomy and it explains most of the marked post-CPB increase in shunt and hypoxemia. Surgery per se contributes to a lesser extent to postoperative atelectasis and gas exchange impairment. PMID- 9366469 TI - Riluzole blocks dopamine release evoked by N-methyl-D-aspartate, kainate, and veratridine in the rat striatum. AB - BACKGROUND: Dopamine (DA) is released in large amounts during cerebral ischemia and may exacerbate tissue damage. Riluzole (54274 RP) is a recently developed agent that depresses glutamate neurotransmission in the central nervous system (CNS) and that may protect against ischemic injury in some animal models. Because glutamate stimulates the release of DA in the striatum, the authors hypothesized that riluzole could antagonize DA release in this structure. METHODS: Assay for DA release consisted of superfusing 3H-DA preloaded synaptosomes with artificial cerebrospinal fluid (1 ml/min, 37 degrees C) and measuring the radioactivity obtained from 1-min fractions over 22 min, first in the absence of any treatment (spontaneous release, 8 min), then in the presence of depolarizing agents combined with riluzole (0.1-100 microM, 5 min), and finally with no pharmacologic stimulation (9 min). The following depolarizing agents were tested: KCl (9, 15 mM), veratridine (0.01-1 microM), N-methyl-D-aspartate (NMDA, 0.1-1 mM), kainate (0.1-1 mM), and nicotine (0.01-0.5 mM). Assay for DA uptake was performed by measuring the radioactivity incorporated in synaptosomes incubated with 3H-DA (44 nM; 5 min; 37 degrees C). RESULTS: All depolarizing agents produced a significant, concentration-related increase from basal 3H-DA release. Riluzole was found to decrease the release induced by veratridine (1 microM), NMDA (1 mM), and kainate (1 mM) in a significant, concentration-related manner (IC50 = 9.5 microM, 1.6 microM, and 5.8 microM for veratridine, NMDA, and kainate, respectively). In contrast, it did not affect the release elicited by either KCl or nicotine. Riluzole had no significant effect on the specific 3H-DA uptake. CONCLUSIONS: Riluzole produced a potent blockade of the release of DA mediated by activation of presynaptic sodium channels, NMDA, and kainate receptors. Depression of glutamate transmission together with blockade of DA release may contribute to the actions of this agent in vivo. PMID- 9366471 TI - Anesthetic-induced preconditioning: previous administration of isoflurane decreases myocardial infarct size in rabbits. AB - BACKGROUND: Experimental evidence suggests that ATP-sensitive potassium channels are involved in myocardial ischemic preconditioning. Because some pharmacologic effects of isoflurane are mediated by K(ATP) channels, the authors tested the hypothesis: Isoflurane administration, before myocardial ischemia, can induce or mimic myocardial preconditioning. METHODS: Myocardial infarct size was measured in three groups of propofol-anesthetized rabbits, each subjected to 30 min of anterolateral coronary occlusion followed by 3 h of reperfusion. Groups differed in their pretreatment: Group 1 (control, N = 13) no pretreatment, Group 2 (ischemic preconditioning, N = 8), 5 min of coronary occlusion and 15 min of reperfusion; Group 3 (isoflurane pretreatment; N = 15), 15 min of isoflurane (1.1% end-tidal) and 15 min of washout. Hemodynamics were monitored serially. Myocardial infarct size and the area at risk were defined using triphenyltetrazolium chloride staining and fluorescent microspheres, respectively, and both were measured using computerized planimetry. RESULTS: Infarct size expressed as a percentage of area at risk was 23.4 +/- 8.5% (mean +/ SD) in the isoflurane group compared with 33.1 +/- 13.3% in controls, and 8.7 +/ 6.2% in the ischemia-preconditioned group. Analysis for coincidental regressions, followed by tests for equality of slope and elevation, showed that the linear relationship between infarct size and area at risk was significantly (P < 0.05) different in all three groups because of differences in line elevation. Minor differences in hemodynamic variables were found between groups, which were unlikely to account for the significant differences in infarct size. CONCLUSION: Preadministration of isoflurane, before myocardial ischemia, reduces myocardial infarct size, and mimics myocardial preconditioning. PMID- 9366470 TI - Ionic basis of the differential effects of intravenous anesthetics on erythromycin-induced prolongation of ventricular repolarization in the guinea pig heart. AB - BACKGROUND: Dysrhythmias and death occur in patients with acquired long QT syndrome (LQTS). Little information exists regarding interactions between anesthetics and drugs that prolong ventricular repolarization. Therefore the effects of three commonly used intravenous anesthetics on ventricular repolarization were investigated in the setting of drug-induced, long QT syndrome. METHODS: The effects of increasing concentrations (0, 10, 25, and 50 microM) of propofol, ketamine, and thiopental on ventricular repolarization were evaluated by measuring the monophasic action potential duration at 90% repolarization (MAPD90) in guinea pig Langendorff-perfused hearts in the absence or presence of erythromycin (100 microM). If an anesthetic enhanced erythromycin induced prolongation of MAPD90, its effects on the delayed rectifier (I[K]) and inward rectifier (I[Kl]) potassium currents were measured using the whole-cell patch-clamp technique. RESULTS: At clinically relevant concentrations, only thiopental significantly modulated erythromycin's effect on MAPD90. Thiopental at 10, 25, and 50 microM prolonged MAPD90 from a control of 163 +/- 6 ms by 18 +/- 4, 30 +/- 3, and 31 +/- 4 ms, respectively. In a separate group, erythromycin prolonged MAPD90 from 155 +/- 2 ms to 171 +/- 2 ms (n = 21, P < 0.001). In the presence of erythromycin, thiopental at 10, 25, and 50 microM caused significantly greater prolongation from a control of 171 +/- 2 ms by 39 +/- 2, 58 +/- 3, and 72 +/- 6 ms, respectively. Whole-cell patch-clamp experiments indicated that thiopental inhibited I(K) and I(Kl). CONCLUSIONS: Intravenous anesthetics caused markedly different effects on ventricular repolarization. Thiopental, unlike propofol and ketamine, potentiated the effects of erythromycin on ventricular repolarization by inhibiting I(K) and I(Kl). PMID- 9366472 TI - Region-specific and agent-specific dilation of intracerebral microvessels by volatile anesthetics in rat brain slices. AB - BACKGROUND: Volatile anesthetics are potent cerebral vasodilators. Although the predominant site of cerebrovascular resistance is attributed to intracerebral arterioles, no studies have compared the actions of volatile anesthetics on intraparenchymal microvessels. The authors compared the effects of halothane and isoflurane on intracerebral arteriolar responsiveness in hippocampal and neocortical microvessels using a brain slice preparation. METHOD: After Institutional Review Board approval, hippocampal or neocortical brain slices were prepared from anesthetized Sprague-Dawley rats and placed in a perfusion recording chamber, superfused with artificial cerebrospinal fluid. Arteriolar diameters were monitored with videomicroscopy before, during, and after halothane or isoflurane were equilibrated in the perfusate. PGF2alpha preconstricted vessels before anesthetic administration. A blinded observer using a computerized videomicrometer analyzed diameter changes. RESULTS: Baseline microvessel diameter and the degree of preconstriction were not different between groups. In the hippocampus, the volatile agents produced similar, concentration-dependent dilation (expressed as percent of preconstricted control +/- SEM) of 68 +/- 6% and 79 +/- 9% (1 MAC) and 120 +/- 3% and 109 +/- 5% (2 MAC) (P < 0.05) during halothane and isoflurane, respectively. In the cerebral cortex, isoflurane caused significantly less vasodilation than did similar MAC levels of halothane (84 +/- 9% vs. 42 +/- 5% dilation at 1 MAC; 121 +/- 4% vs. 83 +/- 5% dilation at 2 MAC halothane vs. isoflurane, respectively). CONCLUSION: Halothane and isoflurane differentially produce dose-dependent dilation of intraparenchymal cerebral microvessels. These findings suggest that local effects of the volatile anesthetics on intracerebral microvessel diameter contribute significantly to alterations in cerebrovascular resistance and support previously described heterogeneous actions on cerebral blood flow produced by these agents. PMID- 9366473 TI - Differential effects of thiopental on neuronal nicotinic acetylcholine receptors and P2X purinergic receptors in PC12 cells. AB - BACKGROUND: PC12 cells, derived from rat pheochromocytoma, express neuronal nicotinic acetylcholine receptors (nAchRs) and P2X purinergic receptors, both of which resemble the receptors in postganglionic sympathetic neurons. The former is the established and the latter is the putative receptor to mediate fast synaptic transmission. The authors investigated effects of thiopental on these two ligand gated ion channels. METHODS: Whole cell currents were recorded in PC12 cells without treatment of nerve growth factor, using conventional whole cell patch clamp technique. Nicotine or adenosine triphosphate (ATP) 30 microM was applied for 4-5 s in the absence or presence of thiopental 3-300 microM. RESULTS: Nicotine induced the rapidly decaying inward current at -60 mV, which exhibited the characteristics of the neuronal nAchR-mediated current. Thiopental inhibited the nicotine-induced inward current and accelerated the current decay in a dose dependent manner, resulting in the greater effects on the steady current than the peak current. IC50s for the peak and steady current were 56.7 and 7.4 microM, when the anesthetic was coapplied with nicotine. Thiopental's inhibition was not associated with a change in the reversal potential and was voltage-independent at membrane potential of -30 to -70 mV. Most of thiopental's effects seemed to require channel opening. In contrast to the nicotine-induced current, thiopental had little effect on the current elicited by ATP. CONCLUSIONS: Thiopental, whose reported EC50 for general anesthesia is 25 microM, inhibited the neuronal nAchR mediated current but not the P2X receptor-mediated response in PC12 cells at clinically relevant concentrations. Inhibition may result in suppression of synaptic transmission in sympathetic ganglia. PMID- 9366474 TI - Beyond the needle: expanding the role of anesthesiologists in the management of chronic non-malignant pain. PMID- 9366475 TI - Postherniorrhaphy pain. PMID- 9366476 TI - How an anesthesiologist can use the ethics consultation service. PMID- 9366477 TI - Unexpected postoperative respiratory failure due to diaphragmatic paralysis. PMID- 9366478 TI - An adult with inherited mitochondrial encephalomyopathy: report of a case. PMID- 9366479 TI - Anaphylactic shock induced by an antiseptic-coated central venous [correction of nervous] catheter. PMID- 9366481 TI - Endotracheal tube obstruction after orogastric tube placement. PMID- 9366480 TI - Air embolization in seated, sedated, spontaneously breathing, neurosurgical patients. PMID- 9366482 TI - Emergent lung separation for management of pulmonary artery rupture. PMID- 9366483 TI - Succinylcholine resistance in a patient with juvenile hyaline fibromatosis. PMID- 9366484 TI - Rate-adaptive cardiac pacing: implications of environmental noise during craniotomy. PMID- 9366485 TI - Treatment of hypotension after hyperbaric tetracaine spinal anesthesia. PMID- 9366486 TI - Interaction of morphine and clonidine on gastrointestinal transit in mice. PMID- 9366487 TI - Visual disturbance and residual paralysis. PMID- 9366488 TI - American Heart Association recommendations for treating tricyclic antidepressant induced hypotension. PMID- 9366489 TI - Response to "rate-adaptive cardiac pacing: implications of environmental noise during craniotomy". PMID- 9366490 TI - Clinical evaluation of a new visualized endotracheal tube (VETT) PMID- 9366491 TI - The detection of successful epidural blockade by subjective assessment of toe temperature elevation. PMID- 9366492 TI - Intraoperative insufflation of the stomach: another approach using a jet ventilator. PMID- 9366493 TI - Activation of fibroblast growth factor 8 gene expression in human embryonal carcinoma cells. AB - To study the role of fibroblast growth factor 8 (FGF-8) in human development and malignancies, we have isolated and characterized its gene. The gene spans 6.0 kbp and is comprised of five exons. Using reverse transcription-polymerase chain reaction, we were able to show that FGF-8 is expressed in two of the seven human mammary carcinoma cell lines tested and in only one of nine breast tumors. In contrast, both of the two normal breast tissues tested express FGF-8. FGF-8 was previously shown to be present in adult testis and ovary. Surprisingly, only one of the seven testis carcinomas and one of 12 ovary carcinomas express FGF-8, whereas all three kidney carcinomas tested express FGF-8. We further showed that fetal brain and lung express FGF-8, whereas fetal intestine and liver do not. Finally, we showed that a teratocarcinoma cell line, Tera-2, can be induced to express FGF-8 mRNA by fetal bovine serum. PMID- 9366494 TI - Concerted stimulation of rat granulosa cell deoxyribonucleic acid synthesis by sex steroids and follicle-stimulating hormone. AB - Although follicle-stimulating hormone (FSH) and estrogens are known to be the main physiological stimuli for the development of the ovarian follicle in mammals, their growth-promoting activity has not been clearly established "in vitro". Furthermore, experimental evidence indicates that FSH and estradiol can independently inhibit granulosa cell proliferation. The present study was aimed at examining the effect of sex steroids in combination with FSH, on DNA synthesis in rat granulosa cells cultured in completely defined medium. Estradiol and FSH, when added separately, produced a significant inhibition of [3H] thymidine incorporation. In contrast, a combination of a low dose of FSH (20 ng/ml) with estradiol (100 ng/ml) produced a shift in the period of maximal DNA synthesis from 96 to 48 h after plating. Dose response studies showed that estradiol effects were produced at physiological intraovarian concentrations (1-100 ng/ml), whereas the effects of FSH were biphasic, with high doses (200 ng/ml) being inhibitory. A similar biphasic dose response curve was observed with increasing concentrations of a cAMP derivative in the presence of maximally effective doses of either an aromatizable steroid (androstenedione), insulin or insulin-like growth factor I. Non-aromatizable androgens (5alpha-dihydrotestosterone, 5alpha androstane 3alpha-17beta diol and androsterone) showed a potency comparable to that of estradiol. The effect of 5alpha-dihydrotestosterone was completely blocked by a specific antiandrogen (hydroxy-flutamide), indicating that it was mediated by the androgen receptor. The effects of estradiol and androgens were not additive. The interaction between estradiol and FSH was further amplified in the presence of a maximally effective dose of insulin. Data presented herein indicate that both estrogens and androgens are able to elicit a mitogenic response in purified granulosa cells, cultured in a completely defined medium, provided the cells are stimulated by a physiological dose of FSH. These results suggest that, during follicular development, the stimulus for granulosa cell proliferation is given by the concerted action of steroid and peptide hormones acting through different signalling pathways. PMID- 9366495 TI - Vitamin D metabolism in human colon adenocarcinoma-derived Caco-2 cells: expression of 25-hydroxyvitamin D3-1alpha-hydroxylase activity and regulation of side-chain metabolism. AB - 1Alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3) and its synthetic analogues exhibit structure-related variations in their growth inhibitory actions in human colon adenocarcinoma-derived Caco-2 cells. Because this might be caused by differences in resistance against metabolic degradation, we used high performance liquid chromatography (HPLC) analysis to investigate pathways of vitamin D metabolism in two different Caco-2 cell clones. Importantly, when Caco-2 cells were incubated with tritium-labelled 25-hydroxyvitamin D3 (25(OH)D3) for up to 2 h they produced almost exclusively a metabolite, which was identified as 1alpha,25(OH)2D3 by co-chromatography with the synthetic standard in two different HPLC systems, and by a radioligand assay showing an identical binding affinity to the intestinal nuclear vitamin D receptor. Expression of the 25(OH)D3 1alpha-hydroxylase appears to be constitutive because almost identical enzyme activities are observed in any growth phase. 1Alpha,25(OH)2D3 can also activate side chain metabolism in Caco-2 cells: thereby, 1alpha,25(OH)2D3 or 25(OH)D3 are metabolized through the C-24 oxidative pathway into 1alpha,24(R),25(OH)3D3 and 24(R),25(OH)2D3, respectively, which undergo sequential metabolism into 1alpha,25(OH)2-24oxo-D3 and 24-oxo-25(OH)D3. Through C-23 oxidation these intermediary metabolites are further converted into 1alpha,23,25(OH)3-24-oxo-D3 and 23,25(OH)2-24-oxo-D3. Also direct C-23 oxidation of the substrates 1alpha,25(OH)2D3 and 25(OH)D3 generates 1alpha,23(S),25(OH)3D3 and 23(S),25(OH)2D3, respectively. In summary, our results demonstrated the presence of distinct pathways of vitamin D metabolism in Caco-2 cells: apart from metabolizing 1alpha,25(OH)2D3 along the C-24 and C-23 oxidative pathways, Caco-2 cells are able to synthesize 1alpha,25(OH)2D3 from 25(OH)D3 through constitutive expression of 25(OH)D3-1alpha-hydroxylase activity. The relevance of this finding for the intrinsic growth control of neoplastic colonocytes is discussed. PMID- 9366496 TI - An artificial intelligence approach to motif discovery in protein sequences: application to steriod dehydrogenases. AB - MEME (Multiple Expectation-maximization for Motif Elicitation) is a unique new software tool that uses artificial intelligence techniques to discover motifs shared by a set of protein sequences in a fully automated manner. This paper is the first detailed study of the use of MEME to analyse a large, biologically relevant set of sequences, and to evaluate the sensitivity and accuracy of MEME in identifying structurally important motifs. For this purpose, we chose the short-chain alcohol dehydrogenase superfamily because it is large and phylogenetically diverse, providing a test of how well MEME can work on sequences with low amino acid similarity. Moreover, this dataset contains enzymes of biological importance, and because several enzymes have known X-ray crystallographic structures, we can test the usefulness of MEME for structural analysis. The first six motifs from MEME map onto structurally important alpha helices and beta-strands on Streptomyces hydrogenans 20beta-hydroxysteroid dehydrogenase. We also describe MAST (Motif Alignment Search Tool), which conveniently uses output from MEME for searching databases such as SWISS-PROT and Genpept. MAST provides statistical measures that permit a rigorous evaluation of the significance of database searches with individual motifs or groups of motifs. A database search of Genpept90 by MAST with the log-odds matrix of the first six motifs obtained from MEME yields a bimodal output, demonstrating the selectivity of MAST. We show for the first time, using primary sequence analysis, that bacterial sugar epimerases are homologs of short-chain dehydrogenases. MEME and MAST will be increasingly useful as genome sequencing provides large datasets of phylogenetically divergent sequences of biomedical interest. PMID- 9366497 TI - Measurement of oestrone sulphatase activity in white blood cells to monitor in vivo inhibition of steroid sulphatase activity by oestrone-3-O-sulphamate. AB - Formation of oestrone via the sulphatase pathway is considered to be a major source of the oestrogen present in breast tumours. Several inhibitors of steroid sulphatase have now been developed for use in the treatment of postmenopausal women with breast cancer. In order to be able to monitor the extent and duration of the inhibition of oestrone sulphatase (E1-STS) readily, we have developed a method to measure the activity of this enzyme in white blood cells (WBCs). Hydrolysis of oestrone sulphate by E1-STS in WBCs was linear with respect to time and the volume of WBCs used. To examine whether the extent of inhibition of E1 STS activity in WBCs, by the inhibitor oestrone-3-O-sulphamate (EMATE), reflected inhibition in other body tissues, activity in WBCs was compared with that in liver and spleen tissue samples from rats. Two hours after an oral dose of EMATE the extent of inhibition of E1-STS detected in WBCs was the same as in the liver. The duration of the inhibition of E1-STS by EMATE, examined over a 1-28 day period in rats, was similar whether monitored in WBCs, liver or spleen. Measurements of E1-STS activity in WBCs were also used to examine the effectiveness of EMATE (0.5 mg/kg) in two male volunteers. E1-STS activity was rapidly inhibited and had only recovered by 27% after 1 month. A marked decrease in the ratio of plasma dehydroepiandrosterone:dehydroepiandrosterone-sulphate (DHA:DHA-S) concentrations was also detected, confirming that EMATE also inhibits DHA-STS activity. The ability to monitor the extent and duration of steroid sulphatase inhibition in WBCs will facilitate the evaluation of this new form of endocrine therapy in women with breast cancer. PMID- 9366498 TI - Characterization of the "estrogenicity" of tamoxifen and raloxifene in HepG2 cells: regulation of gene expression from an ERE controlled reporter vector versus regulation of the endogenous SHBG and PS2 genes. AB - The estrogenic character of tamoxifen and raloxifene was studied on three different genes, an ERE-reporter construct and two endogenous genes, sex hormone binding globulin (SHBG) and pS2, in two variants of the human liver carcinoma cell line HepG2. On the ERE-reporter construct and the pS2 gene both tamoxifen and raloxifene acted as pure estrogen antagonists, whereas on the SHBG gene they functioned as partial estrogens/antiestrogens at concentrations below 1 microM and as full "agonists" at concentrations higher than 1 microM. The fold stimulatory effect of tamoxifen and raloxifene on SHBG protein expression was similar in the estrogen receptor (ER) expressing HepG2 cells (HepER3) and the parental non-ER expressing HepG2 cells at concentrations above 1 microM. In contrast, the 17beta-estradiol analogue moxestrol stimulated SHBG expression only in the HepER3 cells. Both tamoxifen and raloxifene had an additive effect to estrogen receptor-dependent SHBG gene expression in the HepER3 cells in the presence of saturating concentrations of moxestrol. However, a significant difference was observed in that a much higher concentration of moxestrol was required to see an additive effect of raloxifene compared to tamoxifen. The cytokine IL1-beta completely blocked the tamoxifen-dependent induction of SHBG gene expression in HepER3 cells, but only partly blocked the effect of moxestrol mediated by the ER. In conclusion, our results suggest that the mechanism for the liver-selective "estrogenic" character of tamoxifen and raloxifene is mediated by a non-ER dependent pathway. PMID- 9366499 TI - Influence of a transscrotal testosterone propionate administration on the serum level of selected hormones of the hypophyso-gonadal axis. AB - This study was designed to examine the effect of a percutaneous scrotal administration of testosterone propionate (TP) on selected blood variables, in order to identify a reliable anti-doping probe liable to disclose the illicit use of testosterone. Twelve healthy adult males gave their informed consent for the study. Each morning (8:30) and for 10 consecutive days (D), a placebo (D:1,2,3,...8,9,10) or a testosterone propionate (200mg TP on D:... 4,5,6,7...) scrotal patch was installed. On D2 or D3 (placebo-treated) or D7 (TP-treated), venous blood samples were collected at 5 min intervals from 9:00 until 13:00. Serum LH, FSH, 17alpha-hydroxyprogesterone (17HP), testosterone (T), estradiol (E2) and SHBG contents were analysed by immunoassays. The high sampling frequency revealed that TP was associated with the complete abolition of serum LH pulses. Although statistically significant, TP treatment was not related to explicit changes in serum FSH, E2, T/E2 and T/SHBG. TP-induced effects were most significant on serum LH, T and 17HP and were most clearly illustrated by a bi dimensional distribution plot of serum values of the latter variables. The expression of a combination of the latter parameters could eventually serve to detect testosterone misusers. PMID- 9366500 TI - Inhibitors of 25-hydroxyvitamin D3-1alpha-hydroxylase: thiavitamin D analogs and biological evaluation. AB - Six A-ring analogs of 1alpha,25-dihydroxyvitamin D3 (1, 1alpha,25-(OH)2-D3) 3 deoxy-3-thia-1alpha,25-(OH)2-D3 (3), 3-deoxy-3-thia-1alpha,25-(OH)2-D3-3alpha oxide (6), 3-deoxy-3-thia-1alpha,25-(OH)2-D3-3beta-oxide (7) and the 5,6-trans counterparts 5, 8, and 9, respectively--were tested for their ability to inhibit 25-hydroxy-D3-1alpha-hydroxylase (1-OH-ase) in vitro in mitochondria isolated from kidneys of vitamin D deficient chicks. The six analogs were also evaluated in terms of their ability to bind to the chicken intestinal nuclear receptor (VDR) in comparison to the natural hormone 1alpha,25-(OH)2-D3. Analog 7 is not only the best inhibitor of the 1-OH-ase but it also binds effectively to the chick intestinal receptor. It is established that vitamin D analogs must have a 1alpha oxygen group for effective inhibition of the 1-OH-ase. This functional group is also needed for effective binding to the chick intestinal VDR. PMID- 9366501 TI - Specificity of polyclonal antibodies raised against a novel 24,25 dihydroxyvitamin D3-bovine serum albumin conjugant linked through the C-11alpha or C-3 position. AB - Novel hapten-carrier conjugants were prepared by coupling 11 alpha hemiglutaryloxy-(24R)-24,25-dihydroxyvitamin D3 or (24R)-24,25-dihydroxyvitamin D3 [24,25(OH)2D3] 3-hemiglutarate with bovine serum albumin (BSA), to obtain an antibody with high specificity and affinity for use in 24,25(OH)2D3 immunoassay. The polyclonal antibodies showing high titre were each elicited in three or four rabbits against these two conjugants; the antibodies obtained from the former and the latter conjugants were expressed as Ab11 and Ab3, respectively. These had a much higher affinity for 24,25(OH)2D3 than that of the vitamin D binding protein (DBP). Specificity of the antibodies was investigated by crossreactivities with 11 related compounds in a radioimmunoassay (RIA) system. The Abll well discriminated the 1 alpha-hydroxylated metabolites such as 1,24,25(OH)3D3 (< or = 0.69%) and 1,25(OH)2D3 (< or = 0.25%), but significantly crossreacted with some side chain modified compounds such as (24S)-24,25-dihydroxyvitamin D3 [24S,25(OH)2D3] (> or = 67%), 25(OH)D3 (> or = 14%) and 25,26(OH)2D3 (> or = 23%). On the other hand, the Ab3 showed only negligible crossreactivities with the compounds having a different side chain structure such as 24S,25(OH)2D3 (< or = 3.0%), 25(OH)D3 (< 0.3%) and 25,26(OH)2D3 (< or = 0.53%). A significant crossreaction was found only with 1,24,25(OH)3D3 (> or = 68%). These results demonstrated that the Ab3 are promising for developing an immunoassay system which is much more specific and sensitive than conventional competitive protein binding assays based on DBP. PMID- 9366502 TI - Sex and depot-specific stimulation of creatine kinase B in rat adipose tissues by gonadal steroids. AB - We report a sex- and depot-specific response of rat adipose tissues to gonadal steroids. The epididymal fat pad in male rats responded to androgens (testosterone and dihydrotestosterone; DHT), but not to 17beta-estradiol (E2), by increased specific activity of the brain type isozyme of creatine kinase (CK). In female rats, the parametrial fat as well as the fat surrounding the spleen responded to E2 but not to dihydrotestosterone. In both sexes, subcutaneous fat from the inguinal, abdominal or thigh region did not respond to any sex steroid. The parametrial fat showed increasing responsiveness to E2 during postnatal development, in parallel to the response of the uterus. In cycling female rats, parametrial fat showed the highest basal activity of CK at estrus; stimulation by E2 was achieved on all the other days of the cycle. Both phytoestrogens and diethylstilbestrol stimulated CK activity in both parametrial and spleen fat, in parallel to their estrogenic potencies; parametrial fat also responded to progesterone. The stimulation of CK activity in parametrial fat by E2 was completely blocked by actinomycin D or cycloheximide. Treatment with the antiestrogen, tamoxifen, caused moderate stimulation of CK activity in parametrial fat as well as partial inhibition of E2 stimulation of CK activity; the "pure" antiestrogen ICI 164,384 had no agonistic effect and completely blocked the E2 effect. Ovariectomy caused an increased response to E2 without changes in the basal CK activity, but did not lead to any response to DHT. As well as being a reliable response marker, the differential modulation of CK activity can thus serve to distinguish adipose cells from different sources. PMID- 9366503 TI - Differential effects of agonist and antagonists on autoregulation of glucocorticoid receptors in a rat colonic adenocarcinoma cell line. AB - The relative abilities of a potent glucocorticoid receptor (GR) agonist (RU 28362), a weak GR agonist (aldosterone) and a potent GR antagonist (RU 38486) to promote in vivo activation/transformation and subsequent down-regulation of GR mRNA and protein levels were compared using the PROb rat colonic adenocarcinoma cell line. In vivo activation, which is followed immediately by nuclear translocation, by these ligands (1 microM) was evaluated in terms of their abilities to deplete cytoplasmic GR protein levels after a 30 min incubation period. Western blotting experiments with the anti-GR monoclonal antibody BuGR2 demonstrated that a brief incubation with RU 28362 resulted in nearly complete depletion of cytoplasmic GR, whereas incubation with aldosterone resulted in a 50% depletion of the cytoplasmic GR protein. Incubation with RU 38486 was even more effective than aldosterone in promoting this key step in the GR pathway. Prolonged treatment (18 h) with RU 28362 resulted in significant down-regulation of GR mRNA and total cellular GR protein levels. Similar incubation with aldosterone resulted in a transient decrease in the GR mRNA level and also down regulated the total GR protein level. Although prolonged incubation with RU 38486 did not result in detectable down-regulation of the GR mRNA level, this antagonist very effectively down-regulated total cellular GR protein levels. Taken collectively, these data demonstrate that agonists capable of promoting in vivo activation (and subsequent nuclear translocation) of GR are also effective at down-regulating GR at both the mRNA and protein levels. Although the antagonist RU 38486 is also capable of down-regulating GR protein levels by shortening the half-life of the receptor, it appears to be incapable of altering the rate of transcription of the GR gene. Glucocorticoid target tissue sensitivity may thus be decreased via two independent mechanisms: agonist-induced repression of GR gene transcription; and/or ligand-induced degradation of total cellular GR protein levels. PMID- 9366504 TI - The antiovulatory effect of the antiprogestin onapristone could be related to down-regulation of intraovarian progesterone (receptors). AB - The present study was undertaken to investigate intraovarian mechanism(s) for the antiovulatory effect of Onapristone (ON), because antiprogestins possessing the same antiprogestational activity and inhibiting the preovulatory LH surge to the same extent differ in their antiovulatory potency. Ovulation was induced by treating immature female rats with pregnant mare serum gonadotropin (PMSG) for folliculogenesis and hCG for the induction of ovulation. The animals were treated twice with ON (200 mg/kg 42 h and 48 h after PMSG) and killed at different times. The ovulation rate was assessed by counting the number of ova in the fallopian tubes and uteri. Blood and ovaries were collected for radioimmunoassay (RIA) of steroid hormones and histological analysis for 3beta-hydroxysteroid dehydrogenase (3beta-HSDH), 17beta-hydroxysteroid dehydrogenase (17beta-HSDH), progesterone (PR), estrogen (ER) and androgen (AR) receptors. Treatment with ON totally blocked ovulation and the progesterone (P4) surge was significantly diminished in comparison to the control (6-8 h post-hCG), whereas androgen levels remained unaffected. The decreased P4 concentrations correlated well with a reduced staining intensity of 3beta-HSDH in granulosa cells of tertiary follicles. Moreover, we observed a down-regulation of PR in granulosa cells of tertiary follicles. Additionally, in secondary and tertiary follicles the expression of AR between 0 and 6 h after hCG was reduced. These results suggest that the antiovulatory effect of the antiprogestin ON is related to down-regulation of intraovarian progesterone, caused by attenuated 3beta-HSDH activity and PR expression. One can thus assume that intraovarian P4 is an important factor for the induction of ovulation. An effect of ON on the staining intensity of 17beta HSDH in theca and granulosa cells could not be observed at any time. In conclusion, the inhibition of ovulation induced by the antiprogestin, ON, could be related to decreased intraovarian progesterone production through reduced 3beta-HSDH activity and the down-regulation of PR. PMID- 9366505 TI - The effect of tacrine and leupeptin on the secretion of the beta-amyloid precursor protein in HeLa cells. AB - The senile plaque in Alzheimer's disease (AD) consists mainly of the amyloid beta peptide (A beta) derived from a larger beta-amyloid precursor protein (betaAPP). The majority of betaAPP is processed by either a secretory or lysosomal/endosomal pathway. Soluble derivatives of betaAPP (sAPP) and A beta generated by the proteolytic processing of full-length betaAPP are normally secreted into the conditioned medium of cultured cells. Tacrine, a centrally active potent cholinesterase inhibitor that has been shown to improve cognitive functions in some patients with AD, inhibits the secretion of sAPP. Here we have investigated whether leupeptin, a lysosomal protease inhibitor, could influence this effect of tacrine. We analyzed levels of betaAPP derivatives in cultured HeLa cells by immunoblotting cell lysates and conditioned media using the monoclonal antibody 22C11. Levels of sAPP normally present in conditioned media were severely reduced by treating cells with tacrine. The treatment of cells with tacrine resulted in a small decrease in the intracellular levels of betaAPP. The effect of treating the cells with tacrine did not depend upon the growing state of the cells as a similar effect was observed when the drug was added either during initial plating of the cells or after the attachment of the cells. The effect of tacrine was not affected by preincubating the cells with low serum in the culture medium. The treatment of cells with tacrine plus leupeptin reduced the secretion of sAPP in the medium to the same degree as did the treatment with tacrine alone, suggesting that the tacrine-mediated inhibition of sAPP release may not involve leupeptin sensitive proteolytic pathways. The results suggest that the inhibitory effect of tacrine on sAPP secretion is not due to the proteolytic cleavage of the holoprotein in the medium. PMID- 9366506 TI - The effects of postmortem delay on mu, delta and kappa opioid receptor subtypes in rat brain and guinea pig cerebellum evaluated by radioligand receptor binding. AB - Studies of human and animal central nervous system receptor degradation and measurement postmortem are important as human tissue can rarely be collected under ideal experimental conditions. Correlating the change in binding of opioid receptor subtypes over time will help define the conditions under which human studies may be valid. The present study was designed to investigate the rate at which opioid receptor subtypes degrade postmortem. Brains from rats or cerebelli from guinea pigs were kept at 22 degrees C or 4 degrees C at times from zero to 24 hours to simulate two common human collection techniques; room temperature and morgue refrigeration. Tissue homogenates from these brains were analysed for mu1, mu2, delta, kappa1 and kappa3 opioid receptor binding using standard radioligand binding techniques. At room temperature mu1, mu2 and delta opioid receptor binding was reduced between 6 and 12 hours, whereas kappa1 and kappa3 binding was reduced after 24 hours. At 4 degrees C mu1, mu2, delta, kappa1 and kappa3 binding remained constant over the 24 hour period. PMID- 9366507 TI - Myocardial protective effect of trilinolein: an antioxidant isolated from the medicinal plant Panax pseudoginseng. AB - In a previous study we demonstrated that trilinolein, a natural plant triacylglycerol, is a novel myocardial protective agent in vivo. The mechanism probably involves an antioxidant effect. This work investigated the mechanism of myocardial protection of trilinolein to determine if inhibition of calcium influx and alteration of activity of superoxide dismutase are involved. In isolated cardiomyocytes, pretreatment with trilinolein at a low concentration of 10(-9) M effectively reduced 45Ca2+ influx stimulated by hypoxia/normoxia by 34%. In isolated perfused rat heart subjected to 60 min global hypoxemia without reperfusion, pretreatment with 10(-7) M trilinolein for 15 min reduced infarct size by 37%. Assay of superoxide dismutase-mRNA by Northern blot analysis in in vivo rat heart subjected to 30 min ischaemia and 10 min reperfusion showed pretreatment with 10(-7) M trilinolein had a synergistic action with antioxidant systems preventing the rise in superoxide dismutase-mRNA. These results reconfirm the myocardial protection of trilinolein and suggest it may be related to antioxidant activity and inhibition of 45Ca2+ influx. PMID- 9366508 TI - Effects of ethyl-all-cis-5,8,11,14,17-icosapentaenoate (EPA-E), pravastatin and their combination on serum lipids and intimal thickening of cuff-sheathed carotid artery in rabbits. AB - The anti-arteriosclerotic effects of ethyl all-cis-5, 8, 11, 14, 17 icosapentaenoate (EPA-E), pravastatin and their combination in cuff-treated rabbits were investigated. EPA-E at 600 mg/kg, pravastatin at 50 mg/kg or their combination was orally administered once daily for 5 weeks, and each of the animals was sheathed with a cuff on the carotid artery 2 weeks after the beginning of drug administration. EPA-E, pravastatin and their combination significantly reduced serum total cholesterol compared to the control group. EPA E also potently reduced serum triglyceride, while pravastatin only slightly reduced it. The combination of these two agents had the most potent effect on the level of serum triglyceride. Serum phospholipids were also reduced by these treatments in a similar fashion. At the end of treatment, diffuse intimal thickening was observed in the cuff-covered region in all animals in the control group, and the intima/media area ratio in this group was 0.293 +/- 0.038. Treatment with EPA-E alone tended to prevent the intimal thickening, and the intima/media area ratio was 0.209 +/- 0.058 (p = 0.094). This ratio was 0.287 +/- 0.048 (p = 0.902) when pravastatin was administered alone, indicating that it had no significant effect on intimal thickening. The ratio was 0.175 +/- 0.041 (p = 0.042) when both EPA-E and pravastatin were administered, indicating that this combination had a significant inhibitory effect on intimal thickening in the cuff sheathed region. These findings suggest that combined treatment with EPA-E and pravastatin is more effective than respective monotherapies in lowering serum lipids and/or preventing an intimal thickening as events of atherogenesis. PMID- 9366509 TI - Hypothalamic aromatase cytochrome P450 and 5alpha-reductase enzyme activities in pregnant and female rats. AB - The metabolism of steroid hormones in the medial basal hypothalamus (MBH) is known to play a critical role in neural development, the modulation of neuroendocrine function and regulating sexual behavior. While the important biological functions of the aromatase enzyme are well established, the importance of brain 5alpha-reductase has been revealed and elucidated only in the last few years. The distribution and regulation of brain aromatase and 5alpha-reductase enzyme activities have been investigated for the most part in male rats. Therefore, in the present study, MBH aromatase cytochrome P450 and 5alpha reductase activities were characterized in pregnant and female rats during postnatal development under various hormonal conditions. MBH aromatase activity was determined in each tissue sample using the 'tritiated water release' assay, whereas, the 5alpha-reductase rates were determined by thin layer chromatography and scintillation counting of the isolated 5alpha-metabolites. Both activities were highest in infantile animals, then declined with increasing postnatal age; whereas, in aged non-cycling or ovariectomized/adrenalectomized (Ovx/Adx) rats high rates of androgen metabolism were seen in MBH tissue. No significant alterations in MBH aromatase were observed when the 5alpha-reductase pathway was blocked in pregnant animals during late gestation with a known 5alpha-reductase inhibitor (Proscar). However, plasma estradiol levels were significantly increased in the Proscar-treated animals. These results indicate that: 1) the decreasing MBH aromatase and 5alpha-reductase profile (in infantile to adult cycling animals) is developmentally regulated, 2) evidently, there is a divergent regulatory mechanism controlling MBH aromatase versus 5alpha-reductase in aged animals where the aromatase activity increased in aged non-cycling and Ovx/Adx rats while 5alpha-reductase rates remained at moderate levels and, 3) apparently, the 5alpha-reductase pathway is not involved in regulating MBH aromatase activity during late pregnancy. PMID- 9366510 TI - Ketamine effects on bupivacaine local anaesthetic activity and pharmacokinetics of bupivacaine in mice. AB - This study was designed to document possible changes in bupivacaine (B) local anaesthetic activity and pharmacokinetics in mice after a ketamine (K) injection. In the experiments, bupivacaine (8.25 mg.kg(-1)), was injected into the popliteal space of the right posterior limb: the local anaesthetic activity was assessed according to a sciatic nerve blockade method with three different doses (2, 10 and 40 mg/kg) of ketamine and the kinetics were studied after a 10 mg/kg dose. When ketamine was associated, the local anesthetic activity of bupivacaine was significantly enhanced as well as its elimination half-life. Significantly lower levels of the main metabolite, PPX, were observed, when ketamine was associated, suggesting a metabolic inhibition phenomenon. The ketamine-induced increase in the total anaesthetic effect of bupivacaine may thus be explained by kinetic modifications i.e. a possible inhibiting effect of ketamine on the metabolism of bupivacaine. PMID- 9366511 TI - In vitro and in vivo inhibitory actions of morin on rat brain phosphatidylinositolphosphate kinase activity. AB - Phosphatidylinositol-4,5-bisphosphate occupies a central role in signal transduction and in cellular transformation. Phosphatidylinositol-4,5 bisphosphate is produced by the enzymatic phosphorylation of phosphatidylinositol 4-phosphate by phosphatidylinositolphosphate kinase (EC 2.7.1.68). Inhibition of this enzyme might conceivably lowers the cellular pool of phosphatidylinositol 4,5-bisphosphate, thus constituting a feasible control point in regulating signal transduction and cellular transformation. Morin, a plant flavonoid, was demonstrated to exhibit in vitro inhibitory action on phosphatidylinositolphosphate kinase extracted from rat brain. This inhibition of enzymatic activity was found to be dose-dependent, with an IC50 value of approximately 10 microM morin. Lineweaver-Burk transformation of the inhibition data indicates that inhibition was competitive with respect to ATP. The Ki was calculated to be 5.15 x 10(-6) M. Inhibition was uncompetitive with respect to phosphatidylinositol-4-phosphate. The Ki was determined to be 0.94 x 10(-5) M. Administration of morin to rats led to a decrease in phosphatidylinositolphosphate kinase activity in brain extracts. This in vivo action of morin was found to be dose-dependent and time-dependent. These effects of morin on rat brain phosphatidylinositolphosphate kinase activity are discussed in relation to the other reported biological actions of this flavonoid. PMID- 9366512 TI - Effects of quercetin on epithelial chloride secretion. AB - The effect of the flavonoid quercetin on epithelial chloride secretion has been studied in vitro. These studies were performed using monolayers of the human colonic epithelial cell line T84, mounted in modified Ussing chambers. Chloride secretion was assessed as changes in short circuit current (I(SC)) both in basal conditions as well as in response to different secretagogues: carbachol (100 microM), vasoactive intestinal polypeptide (VIP) (10 nM) and prostaglandin E2 (1 microM). Secretion was also induced via protein kinase C by adding phorbol myristate acetate (PMA, 100 nM) in the presence of the calmodulin inhibitor W13 (50 microM). Quercetin (100 microM) was able to promote secretion when the flavonoid was added to the mucosal side of the monolayer. On the contrary, serosal addition of quercetin was devoid of secretory activity and at concentration of 10 microM it was able to inhibit chloride secretion in response to carbachol, prostaglandin E2 and PMA/W13, but not that induced by VIP. We conclude that the effect of quercetin on epithelial chloride secretion is dual, secretory and antisecretory, depending on both the concentration and the side of the monoloayer where the addition of the flavonoid is made. PMID- 9366513 TI - The effects of repeated morphine exposure on mu opioid receptor number and affinity in C57BL/6J and DBA/2J mice. AB - C57BL/6J (B6) mice self-administer substantial quantities of morphine compared to DBA/2J (D2) mice, and most of the genetic component of this strain difference has been attributed to a locus on chromosome 10 in the vicinity of the mu opioid receptor gene. To compare binding characteristics of mu opioid receptor populations between the two strains, mice were given single daily injections of a long-acting preparation of morphine sulfate (80 mg/kg, s.c.) or saline for a period of seven days, and euthanatized six hours after the last injection. Brains were removed and dissected into specific regions. Receptor binding studies were performed on frontal cortex and striatum. Data were analyzed using non-linear regression, and Kd and Bmax comparisons made between strains and treatments. Specific [3H]DAMGO binding in striatum indicates that the density of mu opioid receptors in saline-treated B6 mice and saline-treated D2 mice does not differ significantly. After repeated morphine injection, B6 mice exhibited a decrease in striatal [3H]DAMGO binding, indicating a downregulation of receptor density by approximately 45% (p=.0003 vs saline-treated B6), a phenomenon not observed in D2 mice. In frontal cortex, no differences in [3H]DAMGO binding were observed between strains or treatment groups. These results demonstrate a significant difference between mu opioid receptor regulation in B6 and D2 mice, and may underlie well documented strain differences in specific opioid-related behaviors. PMID- 9366515 TI - Inhibition of LPS-induced TNF-alpha production by calcitonin gene-related peptide (CGRP) in cultured mouse peritoneal macrophages. AB - The purpose of this study was to examine whether rCGRP has effects on TNF-alpha produced by mouse resident peritoneal macrophages. Macrophages were obtained from the peritoneal exudate of male Balb/c mouse. The cells were plated on culture dishes at a density of 2.5x10(5) cells per well and allowed to adhere for 2 hr. Pretreatment with rCGRP (10 nM-1 microM) for 24 hr, the macrophages were cultured with LPS 1 microg/ml for another 24 h. The medium was harvested for measuring TNF alpha by ELISA kits. The results showed that rCGRP had no direct effects on TNF alpha production, but it inhibited LPS-induced TNF-alpha production in a concentration-dependent manner. When rCGRP was at a concentration of 1 microM, the LPS-induced TNF-alpha production was inhibited by 39%. The effect of rCGRP was reversed by hCGRP(8-37) (10 microM), an antagonist of CGRP1 receptor. The LPS induced TNF-alpha production from macrophages was also inhibited by forskolin 3 microM, an activator of adenylate cyclase. Furthermore, pretreatment with H-89 1 microM or Rp-cAMPS 100 microM, the inhibitors of cAMP-dependent protein kinase, the effect of rCGRP was abolished. These data suggest that the LPS-induced TNF alpha production is inhibited by rCGRP via activation of cAMP responses in mouse resident peritoneal macrophages. PMID- 9366514 TI - Alkaline phosphatase expression in cultured endothelial cells of aorta and brain microvessels: induction by interleukin-6-type cytokines and suppression by transforming growth factor betas. AB - Alkaline phosphatase (ALP) activity is markedly high in endothelial cells of the blood-brain barrier (BBB) type but absent from or low in those of the non-BBB type. Interleukin 6 (IL-6) has been identified as a glial cell line-derived factor that induces high ALP activity in cultured aortic endothelial cells. In the present study, we examined the effect of IL-6-type cytokines and transforming growth factor betas (TGF-betas) on ALP expression in cultures of calf pulmonary aortic endothelial (CPAE) cells and porcine brain microvascular endothelial (PBME) cells. Leukemia inhibitory factor, ciliary neurotrophic factor, and oncostatin M, which are known as IL-6-type cytokines, induced high ALP expression in the CPAE cells but not in the PBME cells. ALP levels in these cells were markedly suppressed by culture with TGF-betas. However, in cultured PBME cells, IL-6 and a derivative of cyclic adenosine monophosphate significantly increased ALP activity. Our findings raise the posibility that local concentrations of IL 6, IL-6-type cytokines, and TGF-betas affect the ALP levels in the endothelial cells of aorta and brain microvessels under normal development and also under inflammatory conditions. PMID- 9366516 TI - Distinct effects of MK-801 and (+/-)-2-amino-5-phosphonopentanoic acid on N methyl-D-aspartate-induced rise of brain temperature in rats. AB - Intracerebroventricular (i.c.v.) administration of N-methyl-D-aspartate (NMDA) caused a biphasic rise of brain temperature, namely, a rapid, early rise and a larger, late rise, in urethane-anesthetized rats. I.c.v. pretreatment with a noncompetitive NMDA receptor antagonist, MK-801, attenuated the late rise of the brain temperature, but had no effect on the early rise, whereas i.c.v. pretreatment with a competitive NMDA receptor antagonist, (+/-)-2-amino-5 phosphonopentanoic acid (AP-5), attenuated both rises. AP-5 per se caused a rise in brain temperature without any rise of rectal temperature, whereas MK-801 per se caused no significant change of the brain or rectal temperature. This rise by AP-5 was suppressed by MK-801, suggesting an agonistic effect of AP-5 on NMDA receptors in rat brain in vivo. PMID- 9366517 TI - Inhibition of the DNA-binding and transcriptional repression activity of the Wilms' tumor gene product, WT1, by cAMP-dependent protein kinase-mediated phosphorylation of Ser-365 and Ser-393 in the zinc finger domain. AB - The Wilms' tumor suppressor gene, WT1, encodes a transcription factor in the zinc finger family, which binds to GC-rich sequences and functions as a transcriptional activator or repressor. The WT1 protein plays a crucial role in urogenital development in mammals and its function is thought to be conserved during vertebrate evolution. Although accumulating evidence suggests that WT1 regulates a subset of genes including growth factor and growth factor receptor genes, little is known about regulators or signal cascades that could modulate the function of WT1. In this study, we show that the WT1 protein expressed exogenously in fibroblasts was phosphorylated in vivo, and that treatment with forskolin, which activates the cAMP-dependent protein kinase (PKA) in vivo, induced phosphorylation of additional sites in WT1. We identified the forskolin induced phosphorylation sites as Ser-365 and Ser-393, which lie in the zinc finger domain in zinc fingers 2 and 3, respectively. PKA phosphorylated WT1 at Ser-365 and Ser-393 in vitro, as well as at additional sites, and this phosphorylation abolished the DNA-binding activity of WT1 in vitro. Using WT1 mutants in which Ser-365 and Ser-393 were mutated to Ala individually and in combination, we showed that phosphorylation of these sites was critical for inhibition of DNA binding in vivo. Thus, coexpression of the PKA catalytic subunit with wild type WT1 reduced the level of WT1 DNA-binding activity detected in nuclear extracts, and decreased transcriptional repression activity in vivo. In contrast to wild type WT1, all of the phosphorylation site mutants retained significant DNA-binding activity and repression activity in the presence of PKA. Analysis of the mutants showed that phosphorylation of Ser-365 and Ser-395 had additive inhibitory effects on WT1 DNA-binding in vivo and that phosphorylation at both sites was required for neutralization of repression activity. Therefore, we conclude that PKA modulates the activity of WT1 in vivo through phosphorylation of Ser-365 and Ser-393, which inhibits DNA binding. This in turn results in a decrease in WT1 transcriptional repression. Our findings provide the first evidence that the function of WT1 can be modulated by its phosphorylation in vivo. PMID- 9366518 TI - Functional analysis of wild-type and malignant glioma derived CDKN2Abeta alleles: evidence for an RB-independent growth suppressive pathway. AB - The tumor suppressor gene CDKN2A (p16/MTS1/INK4A), which encodes the cyclin dependent kinase inhibitor p16(INK4a), is a target of 9p21 deletions during the malignant progression of human gliomas. This gene also encodes a second protein product (human p16beta, murine p19ARF), which originates from an unrelated exon of CDKN2A (exon 1beta) spliced onto exon 2 in an alternate reading frame. Cell cycle arrest by p16beta is caused by an as yet unidentified pathway. In order to test the candidacy of p16beta as a glioma suppressor, we replaced p16(INK4a), p15(INK4b) and p16beta wild-type as well as a series of seven glioma-derived p16beta alleles (R87H, A112V, R120H, A121V, G125R, A128A and A128V), into glioma cell lines that had either CDKN2A-/RB+ (U-87MG and U-251MG) or CDKN2A+/RB- (LN 319) endogenous backgrounds and demonstrated that p16beta can act as a functional glioma cell growth suppressor. Moreover, p16beta, but not p16(INK4a) or p15(INK4b) inhibited the growth of RB-negative LN-319 cells, indicating that p16beta likely exerts its effects through an RB-independent pathway. In vitro and in vivo assays of pRB phosphorylation were consistent with this interpretation. Since none of the glioma-derived p16beta mutations inactivated their growth suppressive activities, it appears that mutations in CDKN2A exon 2 (which is shared in the coding sequences of p16(INK4a) and p16beta) likely exclusively target p16(INK4a). PMID- 9366520 TI - Frequent loss of heterozygosity on chromosomes 7 and 9 in benign epithelial ovarian tumours. AB - It is presently unclear if ovarian cancers arise through malignant transformation of pre-existing benign tumours. The apparent rarity of loss of heterozygosity (LOH) reported for benign tumours has led to speculation that they lack malignant potential and represent a biological entity distinct from ovarian carcinoma. We reasoned that the absence of detectable LOH may be due to the masking of such losses by contamination with normal tissue present in excess in the majority of benign tumour biopsies. Therefore we utilized a microdissection technique to examine for LOH using 14 microsatellite markers on chromosome arms 6q, 7p, 7q, 9p, 11q and 17p in 31 solitary benign epithelial ovarian tumours. LOH was detected on all chromosome arms with the most frequent LOH occurring on 7p (27%) and 9p (26%). In addition, a point mutation in codon 157 of TP53 was detected in one tumour which is the first report of a TP53 mutation in a solitary benign ovarian tumour. In total 48% of tumours harboured genetic alterations which supports the idea that all benign ovarian tumours may carry a genetic predisposition to malignancy and are therefore not inherently different from their malignant counterparts. PMID- 9366519 TI - Lyn and Fgr are activated in distinct membrane fractions of human granulocytic cells. AB - We have previously shown that the src-family protein-tyrosine kinase Hck is localized on the azurophil granules of human granulocytes, translocates towards the phagosomes during phagocytosis of opsonized zymosan and is activated during this process. Hck is also activated upon cell stimulation with the calcium ionophore A23187, but not with PMA or the chemotactic peptide fMLP. Here, we investigated whether the src-family kinases Lyn and Fgr are activated under the same conditions. Upon stimulation of human neutrophils or retinoic acid differentiated NB4 cells with fMLP, only Lyn is activated. Cell stimulation with opsonized zymosan or A23187 leads to simultaneous activation of Lyn and Fgr. In cell fractionation experiments with differentiated NB4 cells, the kinases show a similar subcellular localization: Both co-fractionate quantitatively with plasma membrane marker in two fractions that sediment at 11000 g and 200000 g. Lyn is selectively activated in the 200000 g fraction, whereas Fgr is activated in the 11000 g fraction and distinct sets of tyrosine phosphorylated proteins are found in these fractions. The results suggest that these kinases exert their functional roles in distinct cellular compartments in human granulocytic cells. PMID- 9366521 TI - Retinoic acid and the cyclin dependent kinase inhibitors synergistically alter proliferation and morphology of U343 astrocytoma cells. AB - We have characterized the expression and activity of the cell cycle regulatory machinery and the organization of the cytoskeleton of the p16(Ink4a)-deficient astrocytoma cell line, U343 MG-a (U343), following retinoic acid (RA) treatment. RA causes cell cycle arrest at low cell density and significant morphological changes in U343 cells, reflected by reorganization of the intermediate filament, GFAP, and actin. RA-induced cell cycle arrest is also associated with induction of p27Kip1 expression, inhibition of cdk2-associated kinase activity and alteration of the phosphorylation state of the pRB-family proteins. We next determined the effect of inducing expression of the cyclin dependent kinase inhibitors (CKI's), p16(Ink4a), p21Cip1/Waf1 or p27Kip1 on the proliferation and morphology of these malignant astrocytoma cells in the absence and presence of RA. Induction of p16, p21 or p27, using the tetracycline repressor system, potently inhibits proliferation of U343 cells. However, rather than resembling RA treated cells, CKI-induced U343 cells become flat with abundant cytoplasm and perinuclear vacuolization. CKI-induced morphological alterations are accompanied by a significant reorganization of glial filaments within the cytoplasm. Interestingly, when U343 cells are growth arrested by p16, p21 or p27 induction and treated simultaneously with RA, a dramatic morphological change occurs, cells acquiring multiple long, tapering processes reminiscent of primary astrocytes. This rearrangement is accompanied by reorganization of GFAP, vimentin and actin. Vimentin specifically relocalizes to the tips of the long processes which form. The arrangement of intermediate filaments in these cells is, in fact, indistinguishable from their arrangement in primary human astrocytes. These data demonstrate that when a strong proliferative block, produced by CKI expression, occurs in conjunction with the morphogenic signals generated by RA, these p16 deficient malignant astrocytoma cells are induced to phenotypically resemble normal astrocytes. PMID- 9366523 TI - The chimeric oncoproteins E2A-PBX1 and E2A-HLF are concentrated within spherical nuclear domains. AB - Oncogenic mutation of nuclear transcription factors often is associated with altered patterns of subcellular localization that may be of functional importance. The leukemogenic transcription factor gene E2A-PBX1 is created through fusion of the genes E2A and PBX1 as a result of t(1;19) in acute lymphoblastic leukemia. We evaluated subcellular localization patterns of E2A PBX1 protein in transfected cells using immunofluorescence. Full-length E2A-PBX1 was exclusively nuclear and was concentrated in spherical domains denoted chimeric-E2A oncoprotein domains (CODs). In contrast, nuclear fluorescence for wild-type E2A or PBX1 proteins was diffuse. Enhanced concentrations of RNA polymerase II within many CODs and the requirement for an E2A-encoded activation domain suggested transcriptional relevance. However, in situ co-detection of nascent transcripts labeled with bromouridine failed to confirm altered transcriptional activity in relation to CODs. CODs also failed to co-localize with other proteins known to occupy functional nuclear compartments, including the transcription factor PML, the spliceosome-associated protein SC-35 and the adenovirus replication factor DBP, or with foci of DNA replication. Co transfection of Hoxb7, a homeodomain protein capable of enhancing DNA binding by PBX1, impaired COD formation, suggesting that CODs contain E2A-PBX1 protein not associated with DNA. We conclude that, as a 'gain of function' phenomenon requiring protein elements from both E2A and PBX1, COD formation may be relevant to the biology of E2A-PBX1 in leukemogenesis. PMID- 9366522 TI - Adenovirus-mediated p16/CDKN2 gene transfer suppresses glioma invasion in vitro. AB - Malignant gliomas extensively infiltrate the surrounding normal brain, and their diffuse invasion is one of the most important barriers to successful therapy. Recent studies indicate that the progression of gliomas from low-grade to high grade may depend on the acquisition of a new phenotype and the subsequent addition of genetic defects. One of the most frequent abnormalities in the progression of gliomas is the inactivation of tumor-suppressor gene p16, suggesting that loss of p16 is associated with acquisition of malignant characteristics. Consistent with this hypothesis, our previous studies showed that restoring wild-type p16 activity into p16-null malignant glioma cells modified their phenotype. In order to understand whether the biological consequences of p16 inactivation in high-grade gliomas included facilitating invasiveness, we used a recombinant replication-deficient adenovirus carrying the cDNA of the p16/CDKN2 gene to infect and express high levels of p16 protein in p16-null SNB19 glioma cells. Invasion of SNB19 glioma cells was tested into two models: invasion of glioma cells through Matrigel-coated transwell inserts and invasion of tumor-cell spheroids into fetal rat-brain aggregates in a co-culture system. Matrigel invasion assays showed that the SNB19 cells expressing exogenous p16 exhibited significantly reduced invasion. Similarly, invasion of p16-treated SNB19 cells into fetal rat-brain aggregates was reduced during a 72 h time period compared to invasion of the adenovirus-control and mock-infected cells. Expression of matrix metalloproteinase-2 (MMP-2), an enzyme involved in tumor cell invasion, in SNB19 cells expressing p16 was significantly reduced compared to that of parental SNB19 and vector-infected cells. Our results show that restoring wild-type p16 activity into p16-null SNB19 glioma cells significantly inhibits tumor-cell invasion, thus suggesting a novel function of the p16 gene. PMID- 9366524 TI - Dominant-negative CREB inhibits tumor growth and metastasis of human melanoma cells. AB - The ATF/CREB family of eukaryotic transcription factors contain the bZIP structural motif and mediate their transcriptional activities via heterodimerization with ATF and AP-1 family members. Quenching of CREB-associated proteins by a dominant-negative CREB (KCREB) that is mutated within its DNA binding domain decreases radiation resistance of human melanoma cells. The purpose of this study was to determine the role of CREB in tumor growth and metastasis of human melanoma using KCREB. Highly metastatic MeWo human melanoma cells were transfected with the KCREB expression vector and subsequently analysed for changes in their tumorigenic and metastatic potential. Expression of KCREB in MeWo human cells decreased their tumorigenic and metastatic potential in nude mice compared with parental and control transfected cells. The KCREB-transfected cells displayed downregulation of 72 kDa collagenase type IV (MMP-2) mRNA expression and activity and decreased invasiveness through Matrigel-coated filters. Moreover, transcriptional activities mediated by the CAT gene driven by the MMP-2 promoter were decreased by 14-45-fold in KCREB-transfected cells. In addition, the cell-surface adhesion molecule MCAM/MUC18 that is involved in metastasis of human melanoma was downregulated in the KCREB-transfected cells. These data indicate that, through their transcriptional activities, CREB and its associated proteins play an important role in the acquisition of the metastatic phenotype of human melanoma cells. PMID- 9366525 TI - Evidence of a dominant transcriptional pathway which regulates an undifferentiated and complete metastatic phenotype. AB - The highly metastatic amelanotic C8161 human melanoma line was found to exhibit complete dominance of its undifferentiated and metastatic phenotype in multiple somatic cell hybridization studies designed to bypass the presence of potential tumor suppressor genes. In a three armed approach involving somatic cell fusions of C8161 with recipient lines of greater differentiation, different lineage, and different tumorigenicity status, the metastatic and undifferentiated phenotype of C8161 was promiscuously dominant. In somatic cell hybrids produced between the C8161 and a group of non-metastatic human melanoma lines which exhibited melanocyte differentiation markers including S100, HMB-45, NKI/C3, and melanin, the fusions were uniformly metastatic and undifferentiated. In somatic cell hybrids of C8161 and MCF-7 the fusions exhibited an estrogen independent and unresponsive, estrogen receptor (ER) negative, and highly metastatic phenotype. In fusions between C8161 and HMS-1, an immortalized 'benign' human myoepithelial line which produced an abundant extracellular matrix (ECM) and high levels of protease and angiogenic inhibitors including maspin, tissue inhibitor of metalloproteinase-1 (TIMP-1), alpha1-antitrypsin (alpha1-AT), protease nexin II (PN-II), thrombospondin-1 and soluble basic fibroblast growth factor (bFGF) receptors, the hybrids showed complete absence of matrix, absent maspin expression, markedly decreased protease inhibitor and angiogenic inhibitor production, high levels of proteases and angiogenic factors, and a highly metastatic phenotype. In our somatic cell fusions, the human-human hybrids represented true and complete fusions and not hybrid clones selected for by loss of dominant-acting growth suppressor genes. This finding was supported by detailed comparative genomic hybridization (CGH) studies, Q-banding karyotype analysis, and autofusions of representative clones. The purposeful creation of inherently unstable human-murine fusions between C8161 and B16-F1 where loss of putative suppressor loci would be expected, resulted in fusions exhibiting decreased growth and non-metastatic behavior with progressive chromosomal loss. Neither p53, nm23, DNA methyltransferase, activated ras, fibroblast growth factor 4 (FGF-4), or epidermal growth factor receptor (EGFR) mediated the acquisition of the metastatic or undifferentiated phenotype within the C8161-human fusions. These studies are the first studies ever to successfully transfer the complete metastatic phenotype by somatic cell fusion and support the presence of a new high level regulatory pathway(s) involving dominant trans-acting factors which act pleiotropically to regulate an undifferentiated and highly metastatic phenotype. PMID- 9366526 TI - MCF-7 breast carcinoma cells overexpressing FGF-1 form vascularized, metastatic tumors in ovariectomized or tamoxifen-treated nude mice. AB - FGF-1 is expressed in a high proportion of breast tumors. While overexpression of FGF-4 in the MCF-7 breast carcinoma cell line confers the ability to form spontaneously metastasizing tumors in ovariectomized nude mice without estrogen supplementation and in mice that receive tamoxifen pellets, the response of a cell to individual FGFs can be controlled at multiple levels, and the significance of FGF-1 expression in human breast tumors is uncertain. To study the role of FGF-1, MCF-7 human breast cancer carcinoma cells, previously transfected with bacterial beta-galactosidase, were retransfected with FGF-1 expression vectors. FGF-1 transfectants formed large, vascularized tumors in ovariectomized nude mice without estrogen supplementation as well as in mice that received tamoxifen pellets. Lymphatic and pulmonary micrometastases were detected as deposits of X-gal-stained cells as early as 17 days after cell inoculation whereas no metastases were detected in estrogen-supplemented mice bearing similar sized control tumors. When compared with controls, both clonal and polyclonal populations of FGF-1 overexpressing cells exhibited increased anchorage independent growth and decreased population doubling times in estrogen-depleted or 4-hydroxytamoxifen containing medium. These results suggest that FGF signaling may be important in the transition of breast cancer cells from hormone-dependent to hormone-independent and from nonmetastatic to metastatic. PMID- 9366527 TI - Enhancement of Calu-1 human lung carcinoma cell growth in serum-free medium by retinoids: dependence on AP-1 activation, but not on retinoid response element activation. AB - Many lung cancer cell lines are resistant to the growth inhibitory effects of retinoids. However, some small-cell lung cancer cell lines were inhibited by all trans-retinoic acid (ATRA) in serum-free medium. We compared the responses of seven non-small cell lung cancer (NSCLC) cell lines to ATRA in serum-free medium and in medium supplemented with delipidized serum. Whereas the growth of four cell lines was inhibited more in serum-free medium, the growth of the Calu-1 cell line was stimulated by ATRA in a dose-dependent fashion with a maximum at 10(-8) M. Delipidized serum (>2.5%) but not bovine serum albumin (0.15%) suppressed growth stimulation by ATRA. Transcripts of RA receptors RARalpha and RARgamma but not of RARbeta were detected in Calu-1 cells. Receptor expression, the formation of a complex among receptors and a RA-responsive element (RARE), and the transcriptional activation RARE were not suppressed by serum. Natural retinoids and synthetic receptor class- or subtype-selective retinoid agonists, which activated RARs and RXRs for gene transcription from a RARE, and a RAR antagonist (CD2366), which was unable to do so, stimulated the growth of Calu-1 cells in serum-free medium but not in serum-containing medium. Both ATRA and CD2366 enhanced the transcriptional activation of an Activator Protein-1 (AP-1) luciferase reporter construct in serum-free medium but not in delipidized serum. Transcriptional activation of the RARE by ATRA occurred both in the presence or absence of delipidized serum. These results demonstrate that retinoid-induced growth stimulation of Calu-1 cells is associated with enhanced AP-1 transactivation but not with RARE transactivation. PMID- 9366528 TI - Aberrant splicing of the TSG101 and FHIT genes occurs frequently in multiple malignancies and in normal tissues and mimics alterations previously described in tumours. AB - Intragenic deletions of TSG101, the human homolog of a mouse gene (tsg101) that acts to suppress malignant cell growth, were reported in human breast tumours. We screened TSG101 for somatic mutations in DNA and RNA samples isolated from a variety of common human malignancies, EBV-immortalised B-cells, and normal lung parenchyma. Intragenic TSG101 deletions in RNA transcripts were frequently found in all types of samples. Analysis of DNA failed to show genomic rearrangements corresponding to transcripts containing deletions in the same samples. The breakpoints of most transcript deletions coincide with genuine or cryptic splice site sequences, suggesting that they result from alternative or aberrant splicing. A similar spectrum of transcript deletions has previously been described in the putative tumour suppressor gene FHIT. We analysed FHIT in the same series of RNA samples and detected truncated FHIT transcripts frequently in both tumour and normal tissues. In addition, transcripts from TSG101, FHIT and seven other genes were analysed in RNA isolated from normal peripheral blood lymphocytes. Large TSG101 and FHIT intragenic transcript deletions were detected and these appeared to be the predominant transcript in 'aged' lymphocytes. Similar alterations were not detected in transcripts of the other genes which were analysed. Our findings demonstrate that truncated TSG101 and FHIT transcripts are commonly detected in both normal and malignant tissues and that a significant fraction of these are likely to be the result of aberrant splicing. While we cannot exclude that alterations in TSG101 and FHIT occur during cancer development, our data indicate that in this context the commonly observed transcript abnormalities are misleading. PMID- 9366530 TI - Tumour identification using radiopharmaceuticals. PMID- 9366529 TI - Potentiation of lymphomagenesis by methylnitrosourea in mice transgenic for LMO1 is blocked by O6-alkylguanine DNA-alkyltransferase. AB - We evaluated induction of lymphomas by the methylating carcinogen, N methylnitrosourea [MNU], in transgenic mice expressing both LMO1 and the DNA repair gene, MGMT, in the thymus. The goal was to determine whether environmental mutagens shorten the latency or increase the incidence of LMO1 + lymphomas and whether mice transgenic for both LMO1 and MGMT, and thereby able to repair O6 methylguanine DNA adducts induced by MNU, would be protected. Mice heterozygous for LMO1 or MGMT were crossed and offspring treated with MNU at 6 weeks of age. MNU induced lymphoma incidence was highest in the LMO1 mice, 91% and lowest in the hMGMT + mice, 15%. MNU induced K-ras mutations in codon 12 in non-MGMT transgenics resulted in a shorter latency of tumors and accounting for half of the early lymphomas in LMO1 mice. The effect of MNU was abrogated in the LMO1/hMGMT transgenic mice, indicating the ability of MGMT expression to block the carcinogenic effect of MNU even in cancer prone mice. Thus, methylating agents potentiate lymphomagenesis of LMO1, in part through activation of K-ras and the MAPK pathway, a process which appear to synergize with LMO1 mediated transcription activation. O6-alkylguanine DNA-alkyltransferase mediated DNA repair effectively blocks chemical carcinogenesis in mice carrying the LMO1 oncogene. PMID- 9366531 TI - Pictorial review: the imaging features of male breast disease. AB - Although breast carcinoma in men is rare, the presentation of a male patient with evidence of breast enlargement or of a palpable lump, is not uncommon. In such patients, radiological assessment may be requested to exclude malignant change. Mammography has been traditionally the dominant modality of investigation, although ultrasound, using high-frequency linear transducers, is playing an increasingly important role for both imaging and biopsy and the two techniques should be regarded as complementary. In this article the pathological conditions which may affect the male breast are reviewed and the imaging findings presented. PMID- 9366532 TI - Comparison of phased-array and body coils for MR imaging of liver. AB - AIMS AND OBJECTIVES: To compare liver lesion conspicuity using torso phased-array (TPA) and body coils with two pulse sequences. METHODS: Sixty patients with 125 focal hepatic lesions underwent T2-weighted fast spin-echo (T2-FSE) and fast multiplanar inversion recovery (FMPIR) imaging with a standard body coil and with a TPA coil. The first 30 patients were scanned identically in both coils with four acquisitions; the second 30 were scanned with four acquisitions in the body coil and two in the TPA coil. RESULTS: Liver-lesion contrast-to-noise (C/N) was significantly higher for the TPA coil both with four acquisitions (P< 0.001) and with two acquisitions (P < 0.002) using FMPIR, compared to with four acquisitions in the body coil. Liver-lesion C/N for T2-FSE was equivalent in both coils. Liver lesion C/N was significantly higher (P<0.01) for FMPIR than T2-FSE both in the body coil and in the TPA coil. CONCLUSION: Liver-lesion C/N was significantly higher using the TPA coil rather than the body coil. Imaging time can be reduced by decreasing the number of acquisitions with the TPA coil. PMID- 9366533 TI - Appendiceal and peri-appendiceal air at CT: prevalence, appearance and clinical significance. AB - AIM: Appendiceal air has been reported as both a sign of appendicitis and of a normal appendix both at plain radiography and computed tomography (CT). It is the aim of this investigation to determine the prevalence, range of appearances, and significance of appendiceal and peri-appendiceal air at CT. PATIENTS AND METHODS: Appendiceal CT scans of 100 patients with proven appendicitis and 100 patients with a normal appendix were reviewed for the presence of appendiceal and peri appendiceal air. All cases were correlated with surgical and pathological findings or clinical follow-up. RESULTS: In 100 CT cases of appendicitis, appendiceal and/or peri-appendiceal air was present in one or more forms in 31% of cases. When present, it appeared as intraluminal air bubbles (38.7%) or air fluid levels (22.6%), appendolith air (41.9%), intramural air (16.1%), peri appendiceal air bubbles (12.9%), or extraluminal air-fluid level(s) (29.0%). Intramural and extraluminal air correlated with perforation in 60% and 100%, respectively. In 100 CT cases of a normal appendix, air was present in 57%. It was always intraluminal and appeared as small bubbles of air (52.6%), a tubular shaped air collection (43.9%), or as an air-fluid level (3.5%). The appendiceal lumen was either airless (43%), or minimally (32%), moderately (18%), or completely filled with air (7%). CONCLUSION: Air is a common finding at appendiceal CT in both the normal and inflamed appendix. Intraluminal air is seen in both appendicitis and normal appendices, and cannot be presumed to indicate a patent lumen and thus a normal appendix. Appendolith, intramural and peri appendiceal air appear diagnostic of appendicitis. PMID- 9366534 TI - MRI and CT of metastatic hepatocellular carcinoma causing spinal cord compression. AB - We report the imaging features in five patients with metastatic hepatocellular carcinoma causing spinal cord compression, three of which were biopsy proven and two were in patients with known diagnosis of hepatocellular carcinoma. The radiographic, magnetic resonance imaging (MRI) and computed tomography (CT) features are highlighted. Although the occurrence of metastatic disease in hepatocellular carcinoma is exceedingly rare, it may be increasingly encountered as survival of patients is improved with advancing methods of therapy, both surgical and palliative. It often accompanies local recurrence, and invariably signals a grave prognosis with extremely short life expectancy. Unusually, two of the five patients in this series presented initially with skeletal metastases which led to the diagnosis of hepatocellular carcinoma. PMID- 9366535 TI - Sonographic appearance of hepatic Langerhans cell histiocytosis. AB - Periportal lesions were detected on ultrasound in two cases of Langerhans cell histiocytosis with liver involvement. Hypoechoic or hyperechoic lesions were detected in different stages of evolution. Hyperechoic lesions probably corresponded to periportal inflammation whilst hyperechogenicity suggested xanthomatous change. PMID- 9366536 TI - Changing to core biopsy in an NHS breast screening unit. AB - We recently changed from using fine needle aspiration cytology to using core biopsy exclusively in the assessment of screen detected abnormalities. Two hundred and two biopsies (1% of women screened) were performed. Surgical histological confirmation was obtained in 111 patients (101 malignant and 10 benign). The remaining patients were either returned to standard 3-yearly screening or early repeat screening after 1 year. Analysis of the results was performed in accordance with the standards specified in the National Health Service Breast Screening Programme (NHSBSP) Publication Number 22. Absolute sensitivity was 89.3%, complete sensitivity was 93.2%, specificity (including patients undergoing both surgical excision and follow-up) was 88.7%. The predictive value of a positive (malignant) core biopsy result was 100%. The false negative rate was 3.9%. Twelve (5.9%) biopsies were classified inadequate for diagnosis. Core biopsy is a safe and accurate way of assessing screen detected abnormalities and can be used as a substitute for fine needle aspiration cytology with results that exceed the National Health Service Breast Screening Programme target standards, even in the learning phase. PMID- 9366537 TI - MRI in the localization of CSF fistulae: is it of any value? AB - Coronal T2-weighted magnetic resonance imaging (MRI) has been reported to be a useful technique for the localization of both spontaneous and traumatic CSF (cerebro spinal fluid) fistulae. We reviewed the magnetic resonance imaging (MRI) scans of 50 patients with temporal lobe epilepsy in whom such sequences were routinely acquired to determine if this asymptomatic population fulfilled any of the criteria for the diagnosis of a CSF fistula. We found that a large proportion did and conclude that using MRI as the initial radiological investigation in the localization of CSF fistulae is of such low specificity that it is of little or no value. PMID- 9366538 TI - The ureteric jet index: a novel measure of divided renal function. AB - The aim of this study was to evaluate an index of divided renal function based on the quantification of the ureteric jets seen on colour Doppler ultrasound of the bladder. Thirty-one patients attending for scintigraphic renography underwent colour Doppler ultrasound with video recording for 5 min. Divided renal function was calculated as the proportion of jets from the right-sided orifice ('jet index'). This was compared with the corresponding 'scintigraphic index' found using Patlak-Rutland graphical analysis. Absolute discrepancies were calculated. Twenty-eight of thirty-one (90%) of studies were diagnostic for the calculation of jet indices. The mean jet index was 52% (n=28, SEM=5.8%) compared to a mean scintigraphic index of 54% (n = 28, SEM = 4.0%). The two scores were correlated, with a correlation coefficient of 0.72 and the median absolute difference between the two scores was 7.7%. Forty-three per cent (12/28) of subjects had discrepancies in the two scores of 5% or less. The score differences, however, showed a highly skewed distribution with 32% (9/28) subjects showing discrepancies over 20%. This discordant group (> 20% difference) included three patients with functional pelviureteric obstruction, one with a pelvic mass and one with an underfilled bladder. Two patients with very poor quality jets had impaired renal function. In one case, the index improved after angioplasty for renal artery stenosis. This simple test is a useful adjunct to urinary tract ultrasound but should be interpreted alongside evidence of renal obstruction, and complements rather than replaces existing tests. PMID- 9366540 TI - Pelvic musculoskeletal infection in infants -- diagnostic difficulties and radiological features. AB - Musculoskeletal infection involving the pelvis has rarely been reported in infants. When such infections involve the pelvic muscles they are generally believed to result from secondary spread from adjacent structures. We report five cases of primary pelvic musculoskeletal infection affecting infants <1 year, all of which presented during a 1-year period. In two patients the infection appeared to arise primarily in muscle. Clinical features were generally non-specific and often misleading, mimicking hip (4/5) or vascular (3/5) pathology; as a result, diagnosis was delayed in four patients. Radiological investigation was required to make the diagnosis and delineate the extent of the lesion in all cases. Magnetic resonance imaging (MRI) was the most useful imaging technique, accurately identifying the infection and its extent in all cases in which it was used. However, plain films, ultrasound (US), scintigraphy and computed tomography (CT) were all useful in individual cases and have a role in the primary investigation of these difficult infections. The clinical presentation of pelvic musculoskeletal infection in infants and the role of the various radiological investigations in its diagnosis is discussed. PMID- 9366539 TI - Systemic lupus erythematosus patients with respiratory symptoms: the value of HRCT. AB - Ten Chinese patients with systemic lupus erythematosus (SLE) and with persistent respiratory symptoms were evaluated with high resolution computed tomography (HRCT), chest radiographs and lung function tests. Fourteen of 15 HRCT scans performed were abnormal. The predominant disease pattern, seen in 60% of patients, was one of chronic interstitial lung disease with honeycombing, architectural distortion, parenchymal bands, pleural irregularity, and a lower zone predominance. Three of 10 patients had histological evidence of either lung fibrosis or interstitial pneumonitis. Airways disease and pleural thickening were seen in 20% and 87% of scans, respectively. Pleural thickening and honeycombing were present in 53% and 20% of chest radiographs, respectively. All concurrent lung function tests were abnormal. Reduced diffusion capacity of carbon monoxide (DLCO/VA) was observed in 60% of lung function tests. There was no correlation between duration of disease and DLCO/VA. However, pathological reduction of DLCO/VA was seen in 71% of patients with honeycombing, and 88% of patients with ground glass opacity. Our study has documented a high incidence of HRCT features of chronic lung destruction and a lower zone predominance in SLE patients with persistent respiratory symptoms. PMID- 9366541 TI - The use of prophylactic antibiotics in ultrasound-guided transrectal prostate biopsy. AB - The use of antibiotic prophylaxis for transrectal prostate biopsy significantly reduces the incidence of infective complications, but no recommendations exist as to the most appropriate antibiotic regimen. This study was designed to find out which antibiotics were used in different departments and the financial cost of each regimen. A postal survey of 144 hospitals in the UK and Ireland was undertaken. Respondents were asked the name(s), dose(s), route(s) of administration and timing of antibiotics given pre and post biopsy. The response rate was 73.6%. Thirteen different antibiotics were used in 48 different regimens. The most commonly used antibiotic was metronidazole (orally or rectally) in 55% of regimens followed by oral ciprofloxacin in 48% and intravenous gentamicin in 48%. Most regimens (89.7%) contained an oral antibiotic and 58.6% contained an intravenous antibiotic. The cheapest regimen cost 38.7p/patient and the most expensive pounds sterling 21.36/patient, calculated according to prices quoted in the British National Formulary, March 1996. We conclude that there is a lack of standardization in antibiotic prophylaxis for ultrasound-guided transrectal prostate biopsy with widely differing costs for the different regimens. A review of the literature shows that oral antibiotics are inexpensive, well tolerated and effective at reducing the incidence of urinary tract infection and fever following transrectal prostate biopsy. A regimen is proposed including ciprofloxacin or norfloxacin. The addition of oral metronidazole is a subject for further study. PMID- 9366542 TI - A prospective blinded randomized trial comparing oral sodium phosphate and polyethylene glycol solutions for bowel preparation prior to barium enema. AB - PURPOSE: A prospective blinded randomized trial to compare oral sodium phosphate (NaP) solution with polyethylene glycol (PEG) preparations as bowel preparation prior to barium enema examination. PATIENTS AND METHODS: One hundred and ten patients consented to take part and each patient was randomly assigned to receive either NaP (Oral Fleet Prep) or PEG (Lyteprep). The barium enemas were reviewed by two radiologists blinded to the type of bowel preparation the patient had received. The colon was divided into six segments and each segment was assessed for the amount of stool and water present, the adequacy of coating, the ability to exclude inflammatory bowel disease and the presence of polyps. A score of 0-3 (failure to good) was assigned per segment on each of these criteria. RESULTS: The average individual score for the NaP group was 89.2. The average individual score for the PEG group was 88.81. No significant difference was found in the quality of bowel cleansing between the two agents. In particular there was no significant difference in the scores for water retention (two-tailed P = 0.748) and the difference for the quality of coating was considered not quite significant (two-tailed P = 0.0818). CONCLUSION: Oral sodium phosphate cleans the colon as well as polyethylene glycol solutions. The use of NaP will result in significant cost savings and improved patient compliance. PMID- 9366543 TI - Case report: MR features of granulomatous myositis. PMID- 9366544 TI - Case report: malignant lymphomatous polyposis of the colon. PMID- 9366545 TI - Case report: cardiac arrest due to coronary artery spasm during angiographic procedure. PMID- 9366546 TI - Case report: imaging features of desmoplastic small cell tumour of the abdomen. PMID- 9366547 TI - Granulocytic sarcoma as a cause of cord compression. PMID- 9366548 TI - Initiation mechanisms in replication of filamentous phage DNA. AB - Filamentous phage DNA replication occurs in two steps. First, an RNA-primed minus strand is made on the plus strand. Then, a new plus strand is made on the resulting double strand. The RNA primer which initiates synthesis of the minus strand is produced at a specific site on the plus strand template by the host RNA polymerase holoenzyme. Despite a lack of sequences similar to the promoter consensus, the DNA replication origin has a much higher affinity for the holoenzyme than the transcriptional promoters. The non-template strand of the single-stranded -10 region of the origin appears to be responsible for this high affinity. The recognition mechanisms seem to share common features with those in transcriptional promoters. Plus-strand synthesis is initiated by a specific nick introduced into the negatively supercoiled replicative form by the phage-encoded initiator protein. The nicking reaction is preceded by an ordered series of protein-induced DNA conformational changes. PMID- 9366549 TI - Functional interaction of Escherichia coli RNA polymerase with inorganic polyphosphate. AB - BACKGROUND: RNA polymerase from the stationary growth phase cells of Escherichia coli is tightly associated with an acidic compound(s) and exhibits altered promoter selectivity, with reduced transcriptional activity of the genes highly expressed in the exponentially growing cells. Here we have examined the nature of the RNA polymerase-associated acidic compound(s). RESULTS: RNA polymerase isolated from stationary-phase cells of E. coli was found to be tightly associated with inorganic polyphosphates (poly P), and cannot be dissociated even after chromatography on phosphocellulose or DNA-cellulose columns. Since RNA polymerase-poly P complexes reconstituted in vitro showed similar properties, poly P was not binding covalently. The inhibitory effects of poly P on transcription were examined using two forms of the holoenzyme, one containing sigma70, the major sigma for transcription of the genes expressed during exponential cell growth and the other containing sigma38, the principal sigma in the stationary growth phase. At low salt concentrations, poly P inhibited transcription by both Esigma70 and Esigma38 holoenzymes. With an increase in the concentration of potassium glutamate, the poly P inhibition was relieved. At high salt concentrations, the Esigma70 holoenzyme is not able to function, but the Esigma38 holoenzyme is however activated. CONCLUSIONS: These results show that poly P may play a role in the promoter selectivity control of RNA polymerase in E. coli which is growing under conditions of high osmolarity and in the stationary growth phase. PMID- 9366550 TI - Alteration of telomeric sequences and senescence caused by mutations in RAD50 of Saccharomyces cerevisiae. AB - BACKGROUND: Vegetatively dividing cells of Saccharomyces cerevisiae carrying a mutation in RAD50 grow significantly more slowly in rich medium and are sensitive to DNA damage inflicted by X-ray or chemical mutagens. RAD50 function is essential for the formation and repair of meiosis-specific double-strand breaks and chromosome stability. RESULTS: We present evidence for two new phenotypes associated with the rad50delta mutant; shortened telomeres and cell senescence. Comparison of TG1-3 telomeric sequences in an isogenic pair of RAD50 and rad50delta haploid strains showed that they were considerably shortened in the latter. Although rad50delta mutation conferred cell enlargement and slow growth, cell doubling was faster but caused an increase in the frequency of cell death. Telomeres were restored to the wild-type size in hemizygous RAD50/rad50delta and rad50S/rad50delta strains; however, they showed a significant increase in rad50S/rad50S diploid with a concomitant rise in cell viability. Telomeres were stabilized in hemizygous RAD50/rad50delta and rad50S/rad50delta diploids during prolonged growth, suggesting that even a half-dosage of RAD50 is sufficient to conserve the telomere size during successive cell divisions. Furthermore, cells bearing the rad50delta mutation revealed abnormalities in nuclear segregation and, in the presence of hydroxyurea, displayed phenotypes consistent with defects in S-phase checkpoint control. CONCLUSION: This report presents evidence of the involvement of a gene relevant to recombinational repair in the maintenance of telomeres. We conclude that the phenotypes displayed by yeast rad50delta cells have intriguing similarities among the human cell lines representing DNA repair deficient chromosome instability syndromes. PMID- 9366551 TI - Sendai virus-based expression of HIV-1 gp120: reinforcement by the V(-) version. AB - BACKGROUND: We have established a system for recovering Sendai virus (SeV), a nonsegmented negative strand RNA virus, entirely from cDNA at an extremely high rate, and have succeeded in creating a V(-) SeV whose gene expression was greatly enhanced by the deletion of the nonessential V gene. Because of its extreme medical importance, there has been a strong need for the establishment of a better system to express the gp120 envelope glycoprotein of the human immunodeficiency virus type 1 (HIV-1) in sufficient quantity and purity. It also remains to be established to produce gp120 in in vitro natural host cells for HIV 1 such as human primary blood mononuclear cells, macrophages or established T cell lines. RESULTS: Using the above system, we created recombinant Sendai viruses expressing the gp120 in CV1 cells, a monkey kidney line. The expression level from the standard V(+) version has already reached 2.2/microg per 10(6) infected cells, which was readily purified from the culture fluid with a recovery rate of about 60%, and has so far appeared to be functionally and serologically authentic. The inserted gp120 gene was stably maintained during numerous passages of the recombinant virus. The V(-) version-based expression was even more robust, consistently reaching over 6.0 microg per 10(6) cells, a level that is one of the highest currently attainable for gp120 production in mammalian cells. Furthermore, a broad host range of SeV allowed gp120 production in all the three natural host cells for HIV-1 described above. CONCLUSIONS: SeV-based expression serves as a novel choice for producing large quantities of HIV-1 gp120 and will greatly facilitate biochemical, biological and immunological studies of this important glycoprotein. PMID- 9366552 TI - A globular complex formation by Nda1 and the other five members of the MCM protein family in fission yeast. AB - BACKGROUND: In the fission yeast Schizosaccharomyces pombe, Nda1, Nda4, Mis5 and Cdc21 proteins belong to the MCM (minichromosome maintenance) protein family which is thought to have six members. Each MCM member is required for the early stages of DNA replication, and has a well-conserved central 200-amino acid domain containing a putative ATP binding motif. However, the precise molecular functions of MCM proteins are not yet clear. RESULTS: We investigated the physical interaction of Nda1 protein with the other fission yeast MCM proteins using specific antibodies. Immunoprecipitation of Nda1 protein leads to the co precipitation of all the other members of the fission yeast MCM protein family. We purified the MCM protein complex by a combination of column chromatography. The native molecular weight of the MCM complex was estimated by gel filtration to be 560 kDa. The purified fraction contained nearly equal quantities of the six MCM proteins. Electron microscope observation showed that the MCM complex has a globular shape with a central cavity. CONCLUSIONS: We have developed a procedure to purify fission yeast MCM proteins in a native hetero-oligomeric complex form for the first time, which opens an avenue to further biochemical analysis. PMID- 9366553 TI - HIV-1 nuclear import: in search of a leader. AB - The ability of HIV-1 to use host cell nuclear import machinery to translocate the viral preintegration complex into the cell nucleus is the critical determinant in the replication of the virus in non-dividing cells, such as macrophages. In this review, we describe the viral and cellular factors involved in this process. The available data suggest that the process of HIV-1 nuclear import is driven by interaction between nuclear localization signals (NLSs) present on viral proteins matrix and integrase and the cellular NLS receptor, karyopherin alpha. However, this interaction by itself is weak and insufficient to insure effective import of the preintegration complex. Viral protein R (Vpr) functions to increase the affinity of interaction between viral NLSs and karyopherin alpha, thus substantially enhancing the karyophilic potential of the preintegration complex. Interestingly, some cells, in particular HeLa, seem to contain a factor which can substitute for the Vpr's activity, making HIV-1 replication in such cells Vpr independent. We also describe a class of novel anti-HIV compounds which target the NLSs of HIV-1 and effectively block viral replication in T cells and macrophages. PMID- 9366554 TI - Inducible nitric oxide synthase: what difference does it make? PMID- 9366555 TI - Nitric oxide in excitable tissues: physiological roles and disease. PMID- 9366556 TI - Full blockade of intestinal P-glycoprotein and extensive inhibition of blood brain barrier P-glycoprotein by oral treatment of mice with PSC833. AB - Mice lacking mdr1-type P-glycoproteins (mdr1a/1b [-/-] mice) display large changes in the pharmacokinetics of digoxin and other drugs. Using the kinetics of digoxin in mdr1a/1b (-/-) mice as a model representing a complete block of P glycoprotein activity, we investigated the activity and specificity of the reversal agent SDZ PSC833 in inhibiting mdr1-type P-glycoproteins in vivo. Oral PSC833 was coadministered with intravenous [3H]digoxin to wild-type and mdr1a/1b (-/-) mice. The direct excretion of [3H]digoxin mediated by P-glycoprotein in the intestinal mucosa of wild-type mice was abolished by administration of PSC833. Hepatobiliary excretion of [3H]digoxin was markedly decreased in both wild-type and mdr1a/1b (-/-) mice by PSC833, the latter effect indicating that in vivo, PSC833 inhibits not only mdr1-type P-glycoproteins, but also other drug transporters. Upon coadministration of PSC833, brain levels of [3H]digoxin in wild-type mice showed a large increase, approaching (but not equaling) the levels found in brains of PSC833-treated mdr1a/1b (-/-) mice. Thus, orally administered PSC833 can inhibit blood-brain barrier P-glycoprotein extensively, and intestinal P-glycoprotein completely. These profound pharmacokinetic effects of PSC833 treatment imply potential risks, but also promising pharmacological applications of the use of effective reversal agents. PMID- 9366558 TI - In vivo suppression of NF-kappa B and preservation of I kappa B alpha by interleukin-10 and interleukin-13. AB - IL-10 and IL-13 have powerful antiinflammatory activities in vitro and in vivo. In the IgG immune complex model of lung injury in rats, exogenously administered IL-10 or IL-13 have recently been shown to suppress neutrophil recruitment and ensuing lung injury by greatly depressing pulmonary production of TNF alpha. Transcriptional control of the TNF alpha gene is regulated by the nuclear factor kappa B (NF-kappa B). Activation of NF-kappa B involves the degradation of its cytoplasmic inhibitor I kappa B alpha, allowing the nuclear translocation of NF kappa B, with ensuing transcriptional activation. In this study, we sought to determine whether the protective effects of IL-10 and IL-13 in IgG immune complex induced lung injury were mediated by inhibition of NF-kappa B activation. Electrophoretic mobility shift analysis of nuclear extracts from alveolar macrophages and whole lung tissues demonstrated that both IL-10 and IL-13 suppressed nuclear localization of NF-kappa B after in vivo deposition of IgG immune complexes. Western blot analysis indicated that these effects were due to preserved protein expression of I kappa B alpha in both alveolar macrophages and whole lungs. Northern blot analysis of lung mRNA showed that, in the presence of IgG immune complexes, IL-10 and IL-13 augmented I kappa B alpha mRNA expression. These findings suggest that in vivo, IL-10 and IL-13 may operate by suppressing NF-kappa B activation through preservation of I kappa B alpha. PMID- 9366557 TI - Vasopressin potentiates mineralocorticoid selectivity by stimulating 11 beta hydroxysteroid deshydrogenase in rat collecting duct. AB - Arginine vasopressin (AVP) and corticosteroid hormones are involved in sodium reabsorption regulation in the renal collecting duct. Synergy between AVP and aldosterone has been well documented, although its mechanism remains unclear. Both aldosterone and glucocorticoid hormones bind to the mineralocorticoid receptor (MR), and mineralocorticoid selectivity depends on the MR-protecting enzyme 11 beta hydroxysteroid deshydrogenase (11-HSD), which metabolizes glucocorticoids into derivatives with low affinity for MR. We have investigated whether the activity of 11-HSD could be influenced by AVP and corticosteroid hormones. This study shows that in isolated rat renal collecting ducts, AVP increases 11-HSD catalytic activity. This effect is maximal at 10(-8) M AVP (a concentration clearly above the normal physiological range of AVP concentrations) and involves the V2 receptor pathway, while activation of protein kinase C or changes in intracellular calcium are ineffective. The stimulatory effect of AVP on 11-HSD is largely reduced after adrenalectomy, and is selectively restored by infusion of aldosterone, not glucocorticoids. We conclude that this synergy between AVP and aldosterone in controlling the activity of 11-HSD is likely to play a pivotal role in resetting mineralocorticoid selectivity, and hence sodium reabsorption capacities of the renal collecting duct. PMID- 9366559 TI - Heart transplants in interferon-gamma, interleukin 4, and interleukin 10 knockout mice. Recipient environment alters graft rejection. AB - To study the role of cytokines in long-term cardiac allografts we have used recipient mice with targeted gene deletions (-/-) in IFN-gamma, IL-4, or IL-10. In wild-type and IL-4 -/- recipients immunosuppressed with a 30-d course of anti CD4 and anti-CD8, graft survival was > 87 d. This time was significantly reduced in IFN-gamma -/- (62 +/- 19 d, P < 0.05) and IL-10 -/- recipients (55 +/- 4 d, P < 0.0001). Histology showed mononuclear cell infiltration, patchy necrosis, fibrosis, and vascular thickening in all groups. Intragraft transcript levels measured by 32P-reverse transcriptase PCR showed different inflammatory patterns. IFN-gamma -/- recipients had higher IL-2 transcripts and selective alteration in macrophage activation that may have contributed to decreased graft survival. Decreased graft survival in IL-10 -/- recipients was associated with increases in iNOS and IFN-gamma-driven responses. Finally, in grafts from IL-4 -/- recipients, there were increases in CD3 transcripts concurrent with TNF-alpha levels. This increase suggests that IL-4 may regulate T cell infiltration through TNF-alpha mediated inflammatory cell recruitment. Concurrent evaluation of these three isolated cytokine deletions has shown that the recipient environment caused distinct graft modifications. PMID- 9366560 TI - In vitro pharmacologic restoration of CFTR-mediated chloride transport with sodium 4-phenylbutyrate in cystic fibrosis epithelial cells containing delta F508 CFTR. AB - The most common cystic fibrosis transmembrane conductance regulator mutation, delta F508-CFTR, is a partially functional chloride channel that is retained in the endoplasmic reticulum and degraded. We hypothesize that a known transcriptional regulator, sodium 4-phenylbutyrate (4PBA), will enable a greater fraction of delta F508-CFTR to escape degradation and appear at the cell surface. Primary cultures of nasal polyp epithelia from CF patients (delta F508 homozygous or heterozygous), or the CF bronchial epithelial cell line IB3-1 (delta F508/W1282X) were exposed to 4PBA for up to 7 d in culture. 4PBA treatment at concentrations of 0.1 and 2 mM resulted in the restoration of forskolin-activated chloride secretion. Protein kinase A-activated, linear, 10 pS chloride channels appeared at the plasma membrane of IB3-1 cells at the tested concentration of 2.5 mM. Treatment of IB3-1 cells with 0.1-1 mM 4PBA and primary nasal epithelia with 5 mM 4PBA also resulted in the appearance of higher molecular mass forms of CFTR consistent with addition and modification of oligosaccharides in the Golgi apparatus, as detected by immunoblotting of whole cell lysates with anti-CFTR antisera. Immunocytochemistry in CF epithelial cells treated with 4PBA was consistent with increasing amounts of delta F508-CFTR. These data indicate that 4PBA is a promising pharmacologic agent for inducing correction of the CF phenotype in CF patients carrying the delta F508 mutation. PMID- 9366561 TI - Allergen-induced increases in IL-5 receptor alpha-subunit expression on bone marrow-derived CD34+ cells from asthmatic subjects. A novel marker of progenitor cell commitment towards eosinophilic differentiation. AB - We have proposed previously that hemopoietic myeloid progenitors contribute to the ongoing recruitment of proinflammatory cells, namely eosinophils, to sites of allergen challenge in allergic diseases such as asthma. In this study, we investigated the involvement of bone marrow-derived progenitors in the development of allergen-induced pulmonary inflammation in mild asthmatic subjects. By flow cytometry, we enumerated the level of expression of CD34, a hemopoietic progenitor cell marker, on bone marrow aspirates taken before and 24 h after allergen challenge. In addition, the coexpression of the alpha-subunits of IL-3 receptor (IL-3R) and IL-5 receptor (IL-5R) on CD34+ cells was investigated. After allergen-challenge, although no significant change in total BM CD34+ cell numbers was observed, a significant increase in the proportion of CD34+ cells expressing IL-5R alpha, but not IL-3R alpha, was detected in the 24-h post-allergen, compared with the pre-allergen bone marrow. This was associated with a significant blood and sputum eosinophilia and increased methacholine airway responsiveness, 24 h post-allergen. Using simultaneous in situ hybridization and immunocytochemistry, we colocalized the expression of messenger RNA for membrane-bound IL-5R alpha to CD34+ cells. In summary, our data suggest that increased expression of IL-5R alpha on CD34+ cells favors eosinophilopoiesis and may thus contribute to the subsequent development of blood and tissue eosinophilia, a hallmark of allergic inflammation. PMID- 9366562 TI - Colony-stimulating factor-1 induces cytoskeletal reorganization and c-src dependent tyrosine phosphorylation of selected cellular proteins in rodent osteoclasts. AB - Colony-stimulating factor-1 (CSF-1) stimulates motility and cytoplasmic spreading in mature osteoclasts. Therefore, we examined the cellular events and intracellular signaling pathways that accompany CSF-1-induced spreading in normal osteoclasts. To explore the role c-src plays in these processes, we also studied osteoclasts prepared from animals with targeted disruption of the src gene. In normal osteoclasts, CSF-1 treatment induces rapid cytoplasmic spreading, with redistribution of F-actin from a well-delineated central attachment ring to the periphery of the cell. CSF-1 increases membrane phosphotyrosine staining in osteoclasts and induces the phosphorylation of several cellular proteins in cultured, osteoclast-like cells, including c-fms, c-src, and an 85-kD Grb2 binding protein. Src kinase activity is increased threefold after CSF-1 treatment. In src- cells, no attachment ring is present, and CSF-1 fails to induce spreading or a change in the pattern of F-actin distribution. Although c fms becomes phosphorylated after CSF-1 treatment, the 85-kD protein is significantly less phosphorylated in src- osteoclast-like cells. These results indicate that c-src is critical for the normal cytoskeletal architecture of the osteoclast, and, in its absence, the spreading response induced by CSF-1 is abrogated, and downstream signaling from c-fms is altered. PMID- 9366563 TI - Spatiotemporal complexity of ventricular fibrillation revealed by tissue mass reduction in isolated swine right ventricle. Further evidence for the quasiperiodic route to chaos hypothesis. AB - We have presented evidence that ventricular fibrillation is deterministic chaos arising from quasiperiodicity. The purpose of this study was to determine whether the transition from chaos (ventricular fibrillation, VF) to periodicity (ventricular tachycardia) through quasiperiodicity could be produced by the progressive reduction of tissue mass. In isolated and perfused swine right ventricular free wall, recording of single cell transmembrane potentials and simultaneous mapping (477 bipolar electrodes, 1.6 mm resolution) were performed. The tissue mass was then progressively reduced by sequential cutting. All isolated tissues fibrillated spontaneously. The critical mass to sustain VF was 19.9 +/- 4.2 g. As tissue mass was decreased, the number of wave fronts decreased, the life-span of reentrant wave fronts increased, and the cycle length, the diastolic interval, and the duration of action potential lengthened. There was a parallel decrease in the dynamical complexity of VF as measured by Kolmogorov entropy and Poincare plots. A period of quasiperiodicity became more evident before the conversion from VF (chaos) to a more regular arrhythmia (periodicity). In conclusion, a decrease in the number of wave fronts in ventricular fibrillation by tissue mass reduction causes a transition from chaotic to periodic dynamics via the quasiperiodic route. PMID- 9366564 TI - Regulated overexpression of interleukin 11 in the lung. Use to dissociate development-dependent and -independent phenotypes. AB - Standard overexpression transgenic approaches are limited in their ability to model waxing and waning diseases and frequently superimpose development-dependent and -independent phenotypic manifestations. We used the clara cell 10-kD protein (CC10) promoter and the reverse tetracycline transactivator (rtTA) to create a lung-specific, externally regulatable, overexpression transgenic system and used this system to express human interleukin 11 (IL-11) in respiratory structures. Gene induction could be achieved in utero, in neonates and in adult animals. Moreover, gene expression could be turned off by removal of the inducing stimulus. When gene activation was initiated in utero and continued into adulthood, subepithelial airway fibrosis, peribronchiolar mononuclear nodules, and alveolar enlargement (emphysema) were noted. Induction in the mature lung caused airway remodeling and peribronchiolar nodules, but alveolar enlargement was not appreciated. In contrast, induction in utero and during the first 14 d of life caused alveolar enlargement without airway remodeling or peribronchiolar nodules. Thus, IL-11 overexpression causes abnormalities that are dependent (large alveoli) and independent (airway remodeling, peribronchiolar nodules) of lung growth and development, and the CC10-rtTA system can be used to differentiate among these effector functions. The CC10-rtTA transgenic system can be used to model waxing and waning, childhood and growth and development-related biologic processes with enhanced fidelity. PMID- 9366565 TI - Direct in vivo inhibition of the nuclear cell cycle cascade in experimental mesangial proliferative glomerulonephritis with Roscovitine, a novel cyclin dependent kinase antagonist. AB - Glomerular injury is characterized by mesangial cell (MC) proliferation and matrix formation. We sought to determine if reducing the activity of cyclin dependent kinase 2 (CDK2) with the purine analogue, Roscovitine, decreased MC proliferation in vitro and in vivo. Roscovitine (25 microM) inhibited FCS-induced proliferation (P < 0.0001) in cultured MC. Rats with experimental mesangial proliferative glomerulonephritis (Thy1 model) were divided into two groups. A prevention group received daily intraperitoneal injections of Roscovitine in DMSO (2.8 mg/kg) starting at day 1. A treatment group received daily Roscovitine starting at day 3, when MC proliferation was established. Control Thy1 rats received DMSO alone. MC proliferation (PCNA +/OX7 + double immunostaining) was reduced by > 50% at days 5 and 10 in the Roscovitine prevention group, and at day 5 in the treatment group (P < 0.0001). Early administration of Roscovitine reduced immunostaining for collagen type IV, laminin, and fibronectin at days 5 and 10 (r = 0.984; P < 0.001), which was associated with improved renal function (urinary protein/creatinine, blood urea nitrogen, P < 0.05). We conclude that reducing the activity of CDK2 with Roscovitine in experimental glomerulonephritis decreases cell proliferation and matrix production, resulting in improved renal function, and may be a useful therapeutic intervention in disease characterized by proliferation. PMID- 9366566 TI - Intercellular adhesion molecule-1 and CD36 synergize to mediate adherence of Plasmodium falciparum-infected erythrocytes to cultured human microvascular endothelial cells. AB - We have compared the adhesion of Plasmodium falciparum-infected erythrocytes to human dermal microvascular endothelial cells (HDMEC) and human umbilical vein endothelial cells (HUVEC) and have assessed the relative roles of the receptors CD36 and intercellular adhesion molecule-1 (ICAM-1). HUVEC (a cell line that expresses high levels of ICAM-1 but no CD36) mediate low levels of adhesion, whereas HDMEC (which constitutively express CD36) mediate high levels of adhesion even before ICAM-1 induction ICAM-1 expression leads to yet greater levels of adhesion, which are inhibited both by anti-ICAM-1 and CD36 mAbs, despite no increase in the expression of CD36. The results indicate the presence of a substantial population of infected cells that require the presence of both receptors to establish adhesion. Synergy between these receptors could be demonstrated using a number of parasite lines, but it could not be predicted from the binding of these same parasite lines to purified ICAM-1 and CD36. This phenomenon could not be reproduced using either purified receptors presented on plastic, or formalin-fixed HDMEC, suggesting that receptor mobility is important. This is the first study to demonstrate receptor synergy in malaria cytoadherence to human endothelial cells, a phenomenon necessary for parasite survival and associated with disease severity. PMID- 9366567 TI - Constitutive activation of the gastrin-releasing peptide receptor expressed by the nonmalignant human colon epithelial cell line NCM460. AB - Gastrin-releasing peptide (GRP) causes multiple effects in humans by activating a specific heptaspanning receptor. Within the gastrointestinal tract, GRP receptors (GRP-R) are not normally expressed by mucosal epithelial cells except for those lining the gastric antrum. In contrast, recent studies have shown that up to 40% of resected colon cancers aberrantly express this receptor. This is important because the GRP-R can cause the proliferation of many, but not all, tissues in which it is expressed. Since GRP and other agonists are not known to exist in the colonic lumen, it has not been clear how or even if GRP-R expression in colon cancer contributes to cell proliferation. To evaluate the functional consequence of GRP-R expression on colonic epithelium, we transfected the recently isolated nonmalignant human colon epithelial cell line NCM460 with the cDNA for this receptor. All NCM460 cell lines expressing varying numbers of GRP-R bound selected agonists and antagonists indistinguishably from receptors expressed by other human tissues. Furthermore GRP-R-expressing transfected cell lines, but not wild-type NCM460 cells, proliferated independently of serum or other growth factors. Further evaluation revealed that GRP-R in these cells tonically stimulated G alpha q/11, resulting in increased phospholipase C activation. Since transfected cells do not secrete GRP, nor is their growth influenced by exposure to receptor-specific antagonists, these data indicate that GRP-R ectopically expressed by NCM460 cells are constitutively active. This report provides the first evidence of mutation-independent heptaspanning receptor constitutive activation resulting in cell proliferation, and identifies a potential mechanism whereby the GRP-R may act as an oncogene in human colon cancer. PMID- 9366568 TI - Lupus-specific antibodies reveal an altered pattern of somatic mutation. AB - The F4 idiotype is a heavy chain determinant expressed almost exclusively on IgG immunoglobulins and is highly associated with specificity for double-stranded DNA. Since high-titered F4 expression is present predominantly in sera of patients with systemic lupus erythematosus (SLE), we thought F4+ IgG antibodies might constitute a useful subset of immunoglobulins in which to investigate lupus specific alterations in variable (V) region gene expression or in the process of somatic mutation. This molecular analysis of F4+ B cell lines generated from lupus patients demonstrates that despite the strong association of F4 reactivity with specificity for native DNA, there is no apparent VH gene restriction. Furthermore, VH gene segments encoding these antibodies are also used in protective immune responses. An examination of the process of somatic mutation in F4+ antibodies showed no abnormality in frequency of somatic mutation nor in the distribution of mutations in complementarity-determining regions or framework regions. However, there was a decrease in targeting of mutations to putative mutational hot spots. This subtle difference in mutations present in these antibodies may reflect an intrinsic defect in mutational machinery or, more likely, altered state of B cell activation that affects the mutational process and perhaps also negative selection. PMID- 9366569 TI - Pulsatile insulin release from pancreatic islets with nonoscillatory elevation of cytoplasmic Ca2+. AB - The relationship between insulin release and cytoplasmic Ca2+ concentration ([Ca2+]i) was studied in isolated pancreatic islets from ob/ob mice. Although [Ca2+]i was low and stable in the presence of 3 mM glucose, basal insulin release exhibited low amplitude pulsatility, with a frequency of 0.32 +/- 0.04 min-1. Depolarization by raising K+ from 5.9 to 30.9 mM or by the addition of 1 mM tolbutamide caused a pronounced initial insulin pulse followed by declining pulses, but there was no change in frequency. This decline in amplitude of the insulin pulses was prevented in similar experiments performed in the presence of 11 mM glucose. Corresponding measurements of [Ca2+]i in islets exposed to tolbutamide or the high K+ concentration revealed stable elevations without oscillations. Although the [Ca2+]i level is an important determinant for the rate of secretion, the results indicate that pulsatile insulin release does not always depend on [Ca2+]i oscillations. It is suggested that cyclic generation of ATP may fuel pulsatile release under conditions when [Ca2+]i remains stable. PMID- 9366570 TI - Impaired monocyte migration and reduced type 1 (Th1) cytokine responses in C-C chemokine receptor 2 knockout mice. AB - Monocyte chemoattractant protein-1 (MCP-1) is a potent agonist for mononuclear leukocytes and has been implicated in the pathogenesis of atherosclerosis and granulomatous lung disease. To determine the role of MCP-1 and related family members in vivo, we used homologous recombination in embryonic stem cells to generate mice with a targeted disruption of C-C chemokine receptor 2 (CCR2), the receptor for MCP-1. CCR2-/- mice were born at the expected Mendelian ratios and developed normally. In response to thioglycollate, the recruitment of peritoneal macrophages decreased selectively. In in vitro chemotaxis assays, CCR2-/- leukocytes failed to migrate in response to MCP-1. Granulomatous lung disease was induced in presensitized mice by embolization with beads coupled to purified protein derivative (PPD) of Mycobacterium bovis. As compared with wild-type littermates, CCR2-/- mice had a decrease in granuloma size accompanied by a dramatic decrease in the level of interferon gamma in the draining lymph nodes. Production of interferon gamma was also decreased in PPD-sensitized splenocytes from CCR2-/- mice and in naive splenocytes activated by concanavalin A. We conclude that CCR2-/- mice have significant defects in both delayed-type hypersensitivity responses and production of Th1-type cytokines. These data suggest an important and unexpected role for CCR2 activation in modulating the immune response, as well as in recruiting monocytes/macrophages to sites of inflammation. PMID- 9366571 TI - Hepatic secretion of phospholipid vesicles in the mouse critically depends on mdr2 or MDR3 P-glycoprotein expression. Visualization by electron microscopy. AB - Hepatocellular secretion of bile salts into the biliary space induces phospholipid and cholesterol secretion, but the mechanism for integrated lipid secretion is poorly understood. Knockout mice unable to make the canalicular membrane mdr2 P-glycoprotein exhibit normal rates of bile salt secretion, yet are virtually incapable of secreting biliary phospholipid and cholesterol. As the mdr2 P-glycoprotein is thought to mediate transmembrane movement of phospholipid molecules, this mouse model was used to examine the mechanism for biliary phospholipid secretion. In wild-type mdr2 (+/+) mice, ultrarapid cryofixation of livers in situ revealed abundant unilamellar lipid vesicles within bile canalicular lumina. Although 74% of vesicles were adherent to the external aspect of the canalicular plasma membrane, bilayer exocytosis was not observed. Vesicle numbers in mdr2 (+/-) and (-/-) mice were 55 and 12% of wild-type levels, respectively. In a strain of mdr2 (-/-) mice which had been "rescued" by heterozygous genomic insertion of the MDR3 gene, the human homologue of the murine mdr2 gene, vesicle numbers returned to 95% of wild-type levels. Our findings indicate that biliary phospholipid is secreted as vesicles by a process largely dependent on the action of the murine mdr2 P-glycoprotein or human MDR3 P glycoprotein. We conclude that mdr2-mediated phospholipid translocation from the internal to external hemileaflet of the canalicular membrane permits exovesiculation of the external hemileaflet, a vesiculation process promoted by the detergent environment of the bile canalicular lumen. PMID- 9366572 TI - Mutant endoglin in hereditary hemorrhagic telangiectasia type 1 is transiently expressed intracellularly and is not a dominant negative. AB - Endoglin (CD105), a component of the TGF-beta 1 receptor complex, is the target gene for the dominantly inherited vascular disorder hereditary hemorrhagic telangiectasia type 1 (HHT1). We have identified a novel endoglin splice site mutation, leading to an in-frame deletion of exon 3, in a new-born from a family with HHT. Expression of normal and mutant endoglin proteins was analyzed in umbilical vein endothelial cells from this baby and in activated monocytes from the affected father. In both samples, only normal dimeric endoglin (160 kD) was observed at the cell surface, at 50% of control levels. Despite an intact transmembrane region, mutant protein was only detectable by metabolic labeling, as an intracellular homodimer of 130 kD. In monocytes from three clinically affected HHT1 patients, with known mutations creating premature stop codons in exons 8 and 10, surface endoglin was also reduced by half and no mutant was detected. Overexpression into COS-1 cells of endoglin cDNA truncated in exons 7 and 11, revealed their intracellular expression, inability to be secreted and to form heterodimers at the cell surface. These results indicate that mutated forms of endoglin are transiently expressed intracellularly and not likely to act as dominant negative proteins, as proposed previously. A reduction in the level of functional endoglin is thus involved in the generation of HHT1, and associated arteriovenous malformations. PMID- 9366573 TI - Smooth muscle cell expression of type I cyclic GMP-dependent protein kinase is suppressed by continuous exposure to nitrovasodilators, theophylline, cyclic GMP, and cyclic AMP. AB - A key component of the nitric oxide-cyclic guanosine monophosphate (cGMP) pathway in smooth muscle cells (SMC) is the type I GMP-dependent protein kinase (PK-G I). Activation of PK-G I mediates the reduction of cytoplasmic calcium concentrations and vasorelaxation. In this manuscript, we demonstrate that continuous exposure of SMC in culture to the nitrovasodilators S-nitroso-N-acetylpenicillamine (SNAP) or sodium nitroprusside (SNP) results in approximately 75% suppression of PK-G I mRNA by 48 h. PK-G I mRNA and protein were also suppressed by continuous exposure to cGMP analogues 8-bromo- and 8-(4-chlorophenylthio) guanosine-3,5-monophosphate or the cAMP analogue dibutyryl cAMP. These results suggest that activation of one or both of the cyclic nucleotide-dependent protein kinases mediates PK-G I mRNA suppression. Using isoform-specific cDNA probes, only the PK-G I alpha was detected in SMC, either at baseline or after suppression, while PK-G I beta was not detected, indicating that isoform switch was not contributing to the gene regulation. Using the transcription inhibitor actinomycin D, the PK-G I mRNA half life in bovine SMC was observed to be 5 h. The half-life was not affected by the addition of SNAP to actinomycin D, indicating no effect on PK-G I mRNA stability. Nuclear runoff studies indicated a suppression of PK-G I gene transcription by SNAP. PK-G I suppression was also observed in vivo in rats given isosorbide dinitrate in the drinking water, with a dose-dependent suppression of PK-G I protein in the aorta. PK-G I antigen in whole rat lung extract was also suppressed by administration of isosorbide or theophylline in the drinking water. These data may contribute to our understanding of nitrovasodilator resistance, a phenomenon resulting from continuous exposure to nitroglycerin or other nitrovasodilators. PMID- 9366574 TI - Ion composition of airway surface liquid of patients with cystic fibrosis as compared with normal and disease-control subjects. AB - To test whether a major contribution of airways epithelial ion transport to lung defense reflects the regulation of airway surface liquid (ASL) ionic composition, we measured ASL composition using the filter paper technique. On nasal surfaces, the Cl- concentration (approximately 125 meq/liter) was similar to plasma, but the Na+ concentration (approximately 110 meq/liter) was below plasma, and K+ concentration (approximately 30 meq/liter) above plasma. The resting ASL osmolarity [2(Na+ + K+); 277 meq/liter] approximated isotonicity. There were no detectable differences between cystic fibrosis (CF) and normal subjects. In the lower airways, the Na+ concentrations were 80-85 meq/liter, K+ levels approximately 15 meq/liter, and Cl- concentrations 75-80 meq/liter. Measurements of Na+ activity with Na(+)-selective electrodes and osmolality with freezing point depression yielded values consistent with the monovalent cation measurements. Like the nasal surfaces, no differences in cations were detected between CF, normal, or chronic bronchitis subjects. The tracheobronchial ASL hypotonicity was hypothesized to reflect collection-induced gland secretion, a speculation consistent with observations in which induction of nasal gland secretion produced hypotonic secretions. We conclude that there are no significant differences in ASL ion concentrations between CF, normal, and chronic bronchitis subjects and, because ASL ion concentrations exceed values consistent with defensin activity, the failure of CF lung defense may reflect predominantly factors other than salt-dependent defensins. PMID- 9366575 TI - Protease-resistant form of insulin-like growth factor-binding protein 5 is an inhibitor of insulin-like growth factor-I actions on porcine smooth muscle cells in culture. AB - IGFs are pleiotrophic mitogens for porcine smooth muscle cells (pSMC) in culture. The effects of IGFs on cells are modulated by various insulin-like growth factor binding proteins (IGFBP). IGFBP-5 is synthesized by pSMC and binds to the extracellular matrix. However, IGFBP-5 is also secreted into conditioned medium of cultured cells and is cleaved into fragments by a concomitantly produced protease. These fragments have reduced affinity for the IGFs and cleavage makes it difficult to assess the role of intact IGFBP-5. To study the consequence of accumulation of intact IGFBP-5 in medium, we determined the cleavage site in IGFBP-5 and prepared a protease resistant mutant. Amino acid sequencing of purified IGFBP-5 fragments suggested Arg138-Arg139 as the primary cleavage site. Arg138-Arg139-->Asn138-Asn139 mutations were introduced to create protease resistant IGFBP-5, which has the same affinity for IGF-I as the native protein. This mutant IGFBP-5 remained intact even after 24 h of incubation and it inhibited several IGF-I actions when added to pSMC culture medium. The mutant IGFBP-5 (500 ng/ml) decreased IGF-I stimulated cellular DNA synthesis by 84%, protein synthesis by 77%, and it inhibited IGF-I stimulated migration of pSMC by 77%. It also inhibited IGF-I stimulation of IRS-1 phosphorylation. In contrast, the same amount of native IGFBP-5 did not inhibit IGF-I actions. The significance of inhibitory effects of the protease resistant IGFBP-5 was further demonstrated in pSMC transfected with mutant or native IGFBP-5 cDNAs. The mutant IGFBP-5 accumulated in culture medium of transfected cells, while native IGFBP-5 was degraded into fragments, PSMC overexpressing the mutant IGFBP-5 also responded poorly to IGF-I compared with mock transfected cells. IGF-I (5 ng/ml) increased [35S]methionine incorporation into control cells by 36% above the basal level, but it did not significantly change (4%) in pSMC cultures that were producing the mutant IGFBP-5. In conclusion, the accumulation of protease-resistant IGFBP-5 in the medium was inhibitory to IGF-I actions on pSMC. This suggests that proteolysis can prevent IGFBP-5 from acting as an inhibitor of IGF-I-stimulated effects and that it serves as an important mechanism for regulating cellular responsiveness to IGF-I. PMID- 9366576 TI - Identification of the gene encoding the major latency-associated nuclear antigen of the Kaposi's sarcoma-associated herpesvirus. AB - Over 85% of patients with Kaposi's sarcoma (KS) are seropositive for antibodies to the latency-associated nuclear antigen (LANA) expressed in B cell lines infected with Kaposi's sarcoma-associated herpesvirus (KSHV). The presence of antibodies to LANA strongly correlates with the risk of developing the disease. However, the identity of the protein(s) comprising LANA and the corresponding gene(s) has remained unclear. To identify potential latent gene candidates for LANA, we probed total RNA extracted from BCBL-1 cells (a B cell line latently infected with KSHV) using lambda clones that span the KSHV genome. One region encoding latent transcripts spanned KSHV open reading frames (orfs) 71 (K13), 72 (v-cyclin), and 73. Among these, however, only orf 73, when expressed in heterologous mammalian cell systems, reacted with KSHV antibody-positive human sera, resulting in a punctate nuclear staining pattern reminiscent of LANA in BCBL-1 cells. Furthermore, extracts from cells expressing the orf 73 protein product specifically blocked the binding of KS patient antibodies to LANA. Finally, seroreactivity with recombinant orf 73 protein exactly paralleled reactivity with classical LANA as expressed in BCBL-1 cells, both in KS patients and in other groups. Together, these data support the identification of KSHV orf 73 as the gene encoding the dominant immunogenic component of LANA. PMID- 9366577 TI - Calmodulin-stimulated cyclic nucleotide phosphodiesterase (PDE1C) is induced in human arterial smooth muscle cells of the synthetic, proliferative phenotype. AB - The diversity among cyclic nucleotide phosphodiesterases provides multiple mechanisms for regulation of cAMP and cGMP in the cardiovascular system. Here we report that a calmodulin-stimulated phosphodiesterase (PDE1C) is highly expressed in proliferating human arterial smooth muscle cells (SMCs) in primary culture, but not in the quiescent SMCs of intact human aorta. High levels of PDE1C were found in primary cultures of SMCs derived from explants of human newborn and adult aortas, and in SMCs cultured from severe atherosclerotic lesions. PDE1C was the major cAMP hydrolytic activity in these SMCs. PDE expression patterns in primary SMC cultures from monkey and rat aortas were different from those from human cells. In monkey, high expression of PDE1B was found, whereas PDE1C was not detected. In rat SMCs, PDE1A was the only detectable calmodulin-stimulated PDE. These findings suggest that many of the commonly used animal species may not provide good models for studying the roles of PDEs in proliferation of human SMCs. More importantly, the observation that PDE1C is induced only in proliferating SMCs suggests that it may be both an indicator of proliferation and a possible target for treatment of atherosclerosis or restenosis after angioplasty, conditions in which proliferation of arterial SMCs is negatively modulated by cyclic nucleotides. PMID- 9366579 TI - A case-control study of HIV seroconversion in health care workers after percutaneous exposure. Centers for Disease Control and Prevention Needlestick Surveillance Group. AB - BACKGROUND: The average risk of human immunodeficiency virus (HIV) infection after percutaneous exposure to HIV-infected blood is 0.3 percent, but the factors that influence this risk are not well understood. METHODS: We conducted a case control study of health care workers with occupational, percutaneous exposure to HIV-infected blood. The case patients were those who became seropositive after exposure to HIV, as reported by national surveillance systems in France, Italy, the United Kingdom, and the United States. The controls were health care workers in a prospective surveillance project who were exposed to HIV but did not seroconvert. RESULTS: Logistic-regression analysis based on 33 case patients and 665 controls showed that significant risk factors for seroconversion were deep injury (odds ratio= 15; 95 percent confidence interval, 6.0 to 41), injury with a device that was visibly contaminated with the source patient's blood (odds ratio= 6.2; 95 percent confidence interval, 2.2 to 21), a procedure involving a needle placed in the source patient's artery or vein (odds ratio=4.3; 95 percent confidence interval, 1.7 to 12), and exposure to a source patient who died of the acquired immunodeficiency syndrome within two months afterward (odds ratio=5.6; 95 percent confidence interval, 2.0 to 16). The case patients were significantly less likely than the controls to have taken zidovudine after the exposure (odds ratio=0.19; 95 percent confidence interval, 0.06 to 0.52). CONCLUSIONS: The risk of HIV infection after percutaneous exposure increases with a larger volume of blood and, probably, a higher titer of HIV in the source patient's blood. Postexposure prophylaxis with zidovudine appears to be protective. PMID- 9366578 TI - Interleukin-10 promotes activation-induced cell death of SLE lymphocytes mediated by Fas ligand. AB - Immune function in SLE is paradoxically characterized by active T cell help for autoantibody production, along with impaired T cell proliferative and cytokine responses in vitro. To reconcile these observations, we investigated the possibility that the accelerated spontaneous cell death of SLE lymphocytes in vitro is caused by an activation-induced cell death process initiated in vivo. 27 SLE patients, three patients with systemic vasculitis, seven patients with arthritis, and 14 healthy subjects were studied. Patients with clinically active SLE or systemic vasculitis had accelerated spontaneous death of PBMC with features of apoptosis at day 5 of culture. A prominent role for IL-10 in the induction of apoptosis was observed, as neutralizing anti-IL-10 mAb markedly reduced cell death in the active SLE patients by 50%, from 22.3 +/- 5.2% to 11.2 +/- 2.8%, and the addition of IL-10 decreased viability in the active SLE group, but not in the control group, by 38%. In addition, apoptosis was shown to be actively induced through the Fas pathway. The potential clinical relevance of T cell apoptosis in active SLE is supported by the correlation of increased apoptosis and IL-10 levels in vitro with low lymphocyte counts in vivo. We conclude that the spontaneous cell death observed in vitro in lymphocytes from patients with SLE and other systemic autoimmune disorders results from in vivo T cell activation, is actively induced by IL-10 and Fas ligand, and reflects pathophysiologically important events in vivo. Activation-induced cell death in vivo provides a pathogenic link between the aberrant T helper cell activation and impaired T cell function that are characteristic features of the immune system of patients with SLE. PMID- 9366580 TI - Dietary fat intake and the risk of coronary heart disease in women. AB - BACKGROUND: The relation between dietary intake of specific types of fat, particularly trans unsaturated fat and the risk of coronary disease remains unclear. We therefore studied this relation in women enrolled in the Nurses' Health Study. METHODS: We prospectively studied 80,082 women who were 34 to 59 years of age and had no known coronary disease, stroke, cancer, hypercholesterolemia, or diabetes in 1980. Information on diet was obtained at base line and updated during follow-up by means of validated questionnaires. During 14 years of follow-up, we documented 939 cases of nonfatal myocardial infarction or death from coronary heart disease. Mutivariate analyses included age, smoking status, total energy intake, dietary cholesterol intake, percentages of energy obtained from protein and specific types of fat, and other risk factors. RESULTS: Each increase of 5 percent of energy intake from saturated fat, as compared with equivalent energy intake from carbohydrates, was associated with a 17 percent increase in the risk of coronary disease (relative risk, 1.17; 95 percent confidence interval, 0.97 to 1.41; P=0.10). As compared with equivalent energy from carbohydrates, the relative risk for a 2 percent increment in energy intake from trans unsaturated fat was 1.93 (95 percent confidence interval, 1.43 to 2.61; P<0.001); that for a 5 percent increment in energy from monounsaturated fat was 0.81 (95 percent confidence interval, 0.65 to 1.00; P=0.05); and that for a 5 percent increment in energy from polyunsaturated fat was 0.62 (95 percent confidence interval, 0.46 to 0.85; P= 0.003). Total fat intake was not signficantly related to the risk of coronary disease (for a 5 percent increase in energy from fat, the relative risk was 1.02; 95 percent confidence interval, 0.97 to 1.07; P=0.55). We estimated that the replacement of 5 percent of energy from saturated fat with energy from unsaturated fats would reduce risk by 42 percent (95 percent confidence interval, 23 to 56; P<0.001) and that the replacement of 2 percent of energy from trans fat with energy from unhydrogenated, unsaturated fats would reduce risk by 53 percent (95 percent confidence interval, 34 to 67; P<.001). CONCLUSIONS: Our findings suggest that replacing saturated and trans unsaturated fats with unhydrogenated monounsaturated and polyunsaturated fats is more effective in preventing coronary heart disease in women than reducing overall fat intake. PMID- 9366581 TI - Outcome of survivors of accidental deep hypothermia and circulatory arrest treated with extracorporeal blood warming. AB - BACKGROUND: Cardiopulmonary bypass has been used to rewarm victims of accidental deep hypothermia. Unlike other rewarming techniques, it restores organ perfusion immediately in patients with inadequate circulation. This study evaluated the long-term outcome of survivors of accidental deep hypothermia with circulatory arrest who had been rewarmed with cardiopulmonary bypass. METHODS: Deep hypothermia (core temperature, <28 degrees C) with circulatory arrest was found in 46 of 234 patients with accidental hypothermia. In 32 of the 46 patients, rewarming with cardiopulmonary bypass was attempted, resulting in 15 long-term survivors. In most of these patients, deep hypothermia developed after mountaineering accidents or suicide at tempts. After an average (+/-SD) of 6.7+/ 4.0 years of follow-up, we obtained the patients' medical histories and performed neurologic and neuropsychological examinations, neurovascular ultrasound studies, electroencephalography, and magnetic resonance imaging of the brain. RESULTS: The average age of the patients was 25.2+/-9.9 years; seven were female and eight were male. The mean interval from discovery of the patient to rewarming with cardiopulmonary bypass was 141+/-50 minutes (range, 30 to 240). At follow-up there were no hypothermia-related sequelae that impaired quality of life. Neurologic and neuropsychological deficits observed in the early period after rewarming had fully or almost completely disappeared. One patent had cerebellar atrophy on magnetic resonance imaging with mild clinical signs, a condition that may have been caused by hypothermia. Other clinical abnormalities were either preexisting or due to injuries not related to hypothermia CONCLUSIONS: This clinical experience demonstrates that young, otherwise healthy people can survive accidental deep hypothermia with no or minimal cerebral impairment, even with prolonged circulatory arrest. Cardiopulmonary bypass appears to be an efficacious rewarming technique. PMID- 9366582 TI - Short-term inhibition of parathyroid hormone secretion by a calcium-receptor agonist in patients with primary hyperparathyroidism. AB - BACKGROUND: Surgery is the usual therapy for patients with primary hyperparathyroidism. We investigated the ability of a calcimimetic drug that inhibits parathyroid hormone secretion in vitro to decrease serum parathyroid hormone and calcium concentrations in patients with this disorder. METHODS: We performed a randomized, placebo-controlled study of single oral doses of 4 to 160 mg of the calcium-receptor agonist drug R-568 in 20 postmenopausal women with mild primary hyperparathyroidism. At base line, the mean (+/-SE) serum calcium concentration was 10.7+/-0.2 mg per deciliter (2.67+/-0.05 mmol per liter). Serum parathyroid hormone and calcium were measured repeatedly after each dose, and safety was assessed. RESULTS: Administration of R-568 resulted in a dose dependent inhibition of parathyroid hormone secretion. The mean serum parathyroid hormone concentration, which was 77+/-11 pg per milliliter (18.8+/-2.7 pmol per liter; normal range, 16 to 65 pg per milliliter [3.9 to 15.9 pmol per liter) at base line, fell by 26+/-8 percent after 20 mg of R-568 (P=0.03), by 42+/-7 percent after 80 mg (P = 0.01), and by 51+/-5 percent after 160 mg (P=0.005). Serum ionized calcium concentrations fell only after the 160-mg dose, with the decrease closely following the decrease in the serum parathyroid hormone concentration. CONCLUSIONS: The calcimimetic drug R-568 reduces serum parathyroid hormone and ionized calcium concentrations in postmenopausal women with primary hyperparathyroidism. PMID- 9366583 TI - Images in clinical medicine. Mucormycosis of the hand and forearm. PMID- 9366584 TI - Small-vessel vasculitis. PMID- 9366585 TI - Building-related illnesses. PMID- 9366586 TI - Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 36-1997. A 58-year-old man with recurrent ulcerative colitis, bloody diarrhea, and abdominal distention. PMID- 9366587 TI - Postexposure treatment of HIV--taking some risks for safety's sake. PMID- 9366588 TI - Hardened fats, hardened arteries? PMID- 9366589 TI - The treatment of hypothermia. PMID- 9366590 TI - The familial Mediterranean fever gene--cloned at last. PMID- 9366591 TI - The social missions of academic health centers. PMID- 9366592 TI - Infectious disease as an evolutionary paradigm. AB - The basic principles of genetics and evolution apply equally to human hosts and to emerging infections, in which foodborne outbreaks play an important and growing role. However, we are dealing with a very complicated coevolutionary process in which infectious agent outcomes range from mutual annihilation to mutual integration and resynthesis of a new species. In our race against microbial evolution, new molecular biology tools will help us study the past; education and a global public health perspective will help us deal better with the future. PMID- 9366593 TI - Emerging foodborne diseases: an evolving public health challenge. AB - The epidemiology of foodborne disease is changing. New pathogens have emerged, and some have spread worldwide. Many, including Salmonella, Escherichia coli O157:H7, Campylobacter, and Yersinia enterocolitica, have reservoirs in healthy food animals, from which they spread to an increasing variety of foods. These pathogens cause millions of cases of sporadic illness and chronic complications, as well as large and challenging outbreaks over many states and nations. Improved surveillance that combines rapid subtyping methods, cluster identification, and collaborative epidemiologic investigation can identify and halt large, dispersed outbreaks. Outbreak investigations and case-control studies of sporadic cases can identify sources of infection and guide the development of specific prevention strategies. Better understanding of how pathogens persist in animal reservoirs is also critical to successful long-term prevention. In the past, the central challenge of foodborne disease lay in preventing the contamination of human food with sewage or animal manure. In the future, prevention of foodborne disease will increasingly depend on controlling contamination of feed and water consumed by the animals themselves. PMID- 9366596 TI - Public, animal, and environmental health implications of aquaculture. AB - Aquaculture is important to the United States and the world's fishery system. Both import and export markets for aquaculture products will expand and increase as research begins to remove physiologic and other animal husbandry barriers. Overfishing of wild stock will necessitate supplementation and replenishment through aquaculture. The aquaculture industry must have a better understanding of the impact of the "shrouded" public and animal health issues: technology ignorance, abuse, and neglect. Cross-pollination and cross-training of public health and aquaculture personnel in the effect of public health, animal health, and environmental health on aquaculture are also needed. Future aquaculture development programs require an integrated Gestalt public health approach to ensure that aquaculture does not cause unacceptable risks to public or environmental health and negate the potential economic and nutritional benefits of aquaculture. PMID- 9366595 TI - Chronic sequelae of foodborne disease. AB - In the past decade the complexity of foodborne pathogens, as well as their adaptability and ability to cause acute illness, and in some cases chronic (secondary) complications, have been newly appreciated. This overview examines long-term consequences of foodborne infections and intoxications to emphasize the need for more research and education. PMID- 9366598 TI - The impact of consumer demands and trends on food processing. AB - In the United States, consumer demand for new foods and changes in eating habits and food safety risks are affecting the food processing industry. The population is becoming older on average; moreover, consumers want fresh and minimally processed food without synthetic chemical preservatives. To address the need for safer food and compete for consumer acceptance, manufacturers are exploring new food processing and preservation methods. PMID- 9366597 TI - Produce handling and processing practices. AB - In the past decade, outbreaks of human illness associated with the consumption of raw vegetables and fruits (or unpasteurized products produced from them) have increased in the United States. Changes in agronomic, harvesting, distribution, processing, and consumption patterns and practices have undoubtedly contributed to this increase. Pathogens such as Listeria monocytogenes, Clostridium botulinum, and Bacillus cereus are naturally present in some soil, and their presence on fresh produce is not rare. Salmonella, Escherichia coli O157:H7, Campylobacter jejuni, Vibrio cholerae, parasites, and viruses are more likely to contaminate fresh produce through vehicles such as raw or improperly composted manure, irrigation water containing untreated sewage, or contaminated wash water. Contact with mammals, reptiles, fowl, insects, and unpasteurized products of animal origin offers another avenue through which pathogens can access produce. Surfaces, including human hands, which come in contact with whole or cut produce represent potential points of contamination throughout the total system of growing, harvesting, packing, processing, shipping, and preparing produce for consumption. Treatment of produce with chlorinated water reduces populations of pathogenic and other microorganisms on fresh produce but cannot eliminate them. Reduction of risk for human illness associated with raw produce can be better achieved through controlling points of potential contamination in the field; during harvesting; during processing or distribution; or in retail markets, food service facilities, or the home. PMID- 9366599 TI - Impact of changing consumer lifestyles on the emergence/reemergence of foodborne pathogens. AB - Foodborne illness of microbial origin is the most serious food safety problem in the United States. The Centers for Disease Control and Prevention reports that 79% of outbreaks between 1987 and 1992 were bacterial; improper holding temperature and poor personal hygiene of food handlers contributed most to disease incidence. Some microbes have demonstrated resistance to standard methods of preparation and storage of foods. Nonetheless, food safety and public health officials attribute a rise in incidence of foodborne illness to changes in demographics and consumer lifestyles that affect the way food is prepared and stored. Food editors report that fewer than 50% of consumers are concerned about food safety. An American Meat Institute (1996) study details lifestyle changes affecting food behavior, including an increasing number of women in the workforce, limited commitment to food preparation, and a greater number of single heads of households. Consumers appear to be more interested in convenience and saving time than in proper food handling and preparation. PMID- 9366600 TI - Historical overview of key issues in food safety. AB - Foodborne transmission of pathogenic and toxigenic microorganisms has been a recognized hazard for decades. Even half a century ago we knew about the dangers of botulism from underprocessed canned foods; staphylococcal poisoning from unrefrigerated cream-filled pastries, sliced ham, meat, and poultry salads; and salmonellosis from infected animal products. Despite new protective measures, changes in preservation techniques and failure to follow recognized procedures have created new dangers. Moreover, we now recognize new organisms that can cause foodborne illness--Listeria monocytogenes, Escherichia coli O157:H7, Campylobacter jejuni, Vibrio parahaemolyticus, Yersinia enterocolitica, and others. Controlling these organisms will require widespread education and possibly new regulatory initiatives. PMID- 9366601 TI - Quantitative risk assessment: an emerging tool for emerging foodborne pathogens. AB - New challenges to the safety of the food supply require new strategies for evaluating and managing food safety risks. Changes in pathogens, food preparation, distribution, and consumption, and population immunity have the potential to adversely affect human health. Risk assessment offers a framework for predicting the impact of changes and trends on the provision of safe food. Risk assessment models facilitate the evaluation of active or passive changes in how foods are produced, processed, distributed, and consumed. PMID- 9366602 TI - Communicating foodborne disease risk. AB - The food industry, like many others, has a risk communication problem. That problem is manifested in the public's desire to know the truth about outbreaks of foodborne diseases; ongoing concern about the safety of foods, additives, and food-processing procedures; and continued apathy regarding aspects of routine food hygiene. If these concerns are addressed in a coherent and trustworthy way, the public will have better and cheaper food. However, sloppy risk communication can itself cause public health damage. Because citizens are ill-equipped to discriminate among information sources, the food industry as a whole bears responsibility for the successes and failures of its individual members. We review risk communication research and practice for their application to the food industry. PMID- 9366603 TI - Animal diseases of public health importance. AB - The Food and Agriculture Organization's (FAO) interest in emerging diseases caused by foodborne pathogens derives from its role as the leading United Nations agency with a mandate for food quality and safety matters. The Food Quality and Standards Service of FAO's Food and Nutrition Division is active in all areas related to food safety and implements the FAO/World Health Organization Food Standards Program. Its activities include providing assistance to FAO's member nations in addressing problems, strengthening infrastructure, promoting standardization as a means of facilitating trade, and safeguarding the interests of consumers. This paper considers the importance of emerging foodborne diseases from the perspectives of the consumer, international trade in food, producers and processors, and developing countries and addresses prevention and control measures. PMID- 9366604 TI - Consumer concerns: motivating to action. AB - Microbiologic safety is consumers' most frequently volunteered food safety concern. An increase in the level of concern in recent years suggests that consumers are more receptive to educational information. However, changing lifestyles have lessened the awareness of foodborne illness, especially among younger consumers. Failure to fully recognize the symptoms or sources of foodborne disease prevents consumers from taking corrective action. Consumer education messages should include the ubiquity of microorganisms, a comprehensive description of foodborne illnesses, and prevention strategies. Product labels should contain food-handling information and warnings for special populations, and foods processed by newer safety-enhancing technologies should be more widely available. Knowledge of the consequences of unsafe practices can enhance motivation and adherence to safety guidelines. When consumers mishandle food during preparation, the health community, food industry, regulators, and the media are ultimately responsible. Whether inappropriate temperature control, poor hygiene, or another factor, the error occurs because consumers have not been informed about how to handle food and protect themselves. The food safety message has not been delivered effectively. PMID- 9366605 TI - Identifying and controlling emerging foodborne pathogens: research needs. AB - Systems for managing the risks associated with foodborne pathogens are based on detailed knowledge of the microorganisms and the foods with which they are associated--known hazards. An emerging pathogen, however, is an unknown hazard; therefore, to control it, key data must be acquired to convert the pathogen from an unknown to a known hazard. The types of information required are similar despite the identity of the new agent. The key to rapid control is rapid mobilization of research capabilities targeted at addressing critical knowledge gaps. In addition, longer-term research is needed to improve our ability to respond quickly to new microbial threats and help us become more proactive at anticipating and preventing emergence. The type of contingency planning used by the military in anticipating new threats serves as a useful framework for planning for new emergence. PMID- 9366606 TI - Maximizing the usefulness of food microbiology research. AB - Funding for food microbiology research often follows disease outbreaks: botulism from vacuum-packed white-fish chubs, listeriosis from soft cheeses, or illness due to Salmonella Enteritidis or Escherichia coli. As a consequence of research, detection, identification, and subtyping methods improve, and more is learned about pathogenicity and virulence. Research also explores the organisms' capacity to multiply or survive in food and to be killed by established or novel processes. However, rarely is there a critical overview of progress or trustworthy statements of generally agreed-on facts. That information is not maintained in a form that can readily be used by regulatory departments and the food industry to ensure a safe food supply. A centralized system is urgently needed that is accessible electronically and carries information in a standardized format on the essential properties of the organisms, including pathogenicity, methods of detection, enumeration and identification, alternative prevention and control methods, and growth and survival characteristics. PMID- 9366609 TI - Foodborne illness: implications for the future. AB - Many outbreaks of foodborne illness, even those involving newly recognized pathogens, could have been avoided if certain precautions had been taken. This article will draw on existing information to suggest realistic measures that, if implemented, are most likely to avert or diminish the impact of new foodborne disease outbreaks. PMID- 9366607 TI - Epidemiology and detection as options for control of viral and parasitic foodborne disease. AB - Human enteric viruses and protozoal parasites are important causes of emerging food and waterborne disease. Epidemiologic investigation and detection of the agents in clinical, food, and water specimens, which are traditionally used to establish the cause of disease outbreaks, are either cumbersome, expensive, and frequently unavailable or unattempted for the important food and waterborne enteric viruses and protozoa. However, the recent introduction of regulatory testing mandates, alternative testing strategies, and increased epidemiologic surveillance for food and waterborne disease should significantly improve the ability to detect and control these agents. We discuss new methods of investigating foodborne viral and parasitic disease and the future of these methods in recognizing, identifying, and controlling disease agents. PMID- 9366608 TI - Quantitative microbiology: a basis for food safety. AB - Because microorganisms are easily dispersed, display physiologic diversity, and tolerate extreme conditions, they are ubiquitous and may contaminate and grow in many food products. The behavior of microbial populations in foods (growth, survival, or death) is determined by the properties of the food (e.g., water activity and pH) and the storage conditions (e.g., temperature, relative humidity, and atmosphere). The effect of these properties can be predicted by mathematical models derived from quantitative studies on microbial populations. Temperature abuse is a major factor contributing to foodborne disease; monitoring temperature history during food processing, distribution, and storage is a simple, effective means to reduce the incidence of food poisoning. Interpretation of temperature profiles by computer programs based on predictive models allows informed decisions on the shelf life and safety of foods. In- or on-package temperature indicators require further development to accurately predict microbial behavior. We suggest a basis for a "universal" temperature indicator. This article emphasizes the need to combine kinetic and probability approaches to modeling and suggests a method to define the bacterial growth/no growth interface. Advances in controlling foodborne pathogens depend on understanding the pathogens' physiologic responses to growth constraints, including constraints conferring increased survival capacity. PMID- 9366610 TI - Vero cytotoxin-producing Escherichia coli O157 outbreaks in England and Wales, 1995: phenotypic methods and genotypic subtyping. AB - Vero cytotoxin-producing Escherichia coli O157 belonging to four phage types (PTs) caused 11 outbreaks of infection in England and Wales in 1995. Outbreak strains of different PTs were distinguishable by DNA-based methods. Pulsed-field gel electrophoresis best discriminated among strains belonging to the same PT, distinguishing six of the seven PT2 outbreak strains and both PT49 outbreak strains. PMID- 9366612 TI - Irradiation pasteurization of solid foods: taking food safety to the next level. PMID- 9366611 TI - Genetic polymorphism among Cryptosporidium parvum isolates: evidence of two distinct human transmission cycles. AB - We report the results of molecular analysis of 39 isolates of Cryptosporidium parvum from human and bovine sources in nine human outbreaks and from bovine sources from a wide geographic distribution. All 39 isolates could be divided into either of two genotypes, on the basis of genetic polymorphism observed at the thrombospondin-related adhesion protein (TRAP-C2) locus. Genotype 1 was observed only in isolates from humans. Genotype 2, however, was seen in calf isolates and in isolates from a subset of human patients who reported direct exposure to infected cattle or consumed items thought to be contaminated with cattle faces. Furthermore, experimental infection studies showed that genotype 2 isolates were infective to mice or calves under routine laboratory conditions, whereas genotype 1 isolates were not. These results support the occurrence of two distinct transmission cycles of C. parvum in humans. PMID- 9366613 TI - Non-O157 Shiga toxin-producing Escherichia coli infections in Europe. PMID- 9366614 TI - The taxonomy of Cyclospora. PMID- 9366615 TI - Tobacco as a cause of lung cancer: some reflections. PMID- 9366616 TI - Is Gulf War syndrome due to stress? The evidence reexamined. AB - Medical policy-makers have concluded that stress from wartime trauma and deployment constitutes an important cause of the chronic physical symptoms observed in US veterans who served in the Persian Gulf War. The author reviewed scientific articles from peer-reviewed journals referenced in the final report of the Presidential Advisory Committee on Gulf War Veterans' illnesses and conducted a MEDLINE literature search. All reported prevalence rates of post-traumatic stress disorder (PTSD) in Gulf War veterans were defined by critical cutpoints on psychometric scales constructed by summing veterans' responses on standardized symptom questionnaires rather than by clinical psychiatric interviews. Observed PTSD rates varied from 0% to 36% (mean, 9%). Correcting for measurement errors with previously determined values of the sensitivity (range 0.77 to 0.96) and specificity (range 0.62 to 0.89) of the psychometric tests yielded estimated true PTSD rates of 0% for 18 of the 20 reported rates. Mean scores on the Mississippi PTSD scale in all subgroups of Gulf War veterans were within the range of values for well-adjusted Vietnam veterans (50-89) and far below that of Vietnam veterans with psychiatrically confirmed PTSD (120-140). Most PTSD and "stress-related symptoms" reported in studies of Gulf War veterans appear to represent false positive errors of measurement reflecting nonspecific symptoms of other conditions. PMID- 9366617 TI - Invited commentary: how would we know a Gulf War syndrome if we saw one? PMID- 9366618 TI - Sample size requirements in case-only designs to detect gene-environment interaction. AB - With advances in molecular genetic technology, more studies will examine gene environment interaction in disease etiology. If the primary purpose of the study is to estimate the effect of gene-environment interaction in disease etiology, one can do so without employing controls. The case-only design has been promoted as an efficient and valid method for screening for gene-environment interaction. The authors derive a method for estimating sample size requirements, present sample size estimates, and compare minimum sample size requirements to detect gene-environment interaction in case-only studies with case-control studies. Assuming independence between exposure and genotype in the population, the authors believe that the case-only design is more efficient than a case-control design in detecting gene-environment interaction. They also illustrate a method to estimate sample size when information on marginal effects (relative risk) of exposure and genotype is available from previous studies. PMID- 9366619 TI - Risk factors for inguinal hernia in women: a case-control study. The Coala Trial Group. AB - Potential risk factors for inguinal hernia in women were investigated and the relative importance of these factors was quantified. In women, symptomatic but nonpalpable hernias often remain undiagnosed. However, knowledge on this subject only concerns hernia and operation characteristics, which have been obtained by review of case series. Virtually nothing is known about risk factors for inguinal hernia. The authors performed a hospital-based case-control study of 89 female patients with an incident inguinal hernia and 176 age-matched female controls. Activity since birth with two validated questionnaires was measured and smoking habits, medical and operation history, Quetelet index (kg/m2), and history of pregnancies and deliveries were recorded. Response for cases was 81% and for controls 73%. Total physical activity was not associated with inguinal hernia (univariate odds ratio (OR) = 0.8, 95% confidence interval (CI) 0.6-1.1), but high present sports activities was associated with less inguinal hernia (multivariate OR = 0.2, 95% CI 0.1-0.7). Obesity (Quetelet index > 30) was also protective for inguinal hernia (OR = 0.2, 95% CI 0.04-1.0). Independent risk factors were positive family history (OR = 4.3, 95% CI 1.9-9.7) and obstipation (OR = 2.5, 95% CI 1.0-6.7). In particular, smoking, appendectomy, other abdominal operations, and multiple deliveries were not associated with inguinal hernia in females. The protective effect of present sports activity may be explained by optimizing the resistance of the abdominal musculature protecting the relatively small inguinal weak spot in the female. The individual predisposition for inguinal hernia may be quantified by these risk factors, and, with this in mind, the authors advise that further evaluation might be needed for the patient with unexplained inguinal pain. PMID- 9366620 TI - Alcohol consumption and changes in blood pressure among African Americans. The Pitt County Study. AB - The Pitt County Study is a longitudinal investigation of anthropometric, psychosocial, and behavioral predictors of hypertension in African Americans who were aged 25-50 years at baseline in 1988. At baseline, a strong dose-response gradient was observed for alcohol consumption and blood pressure for both sexes. The current study investigated whether baseline alcohol consumption or, alternatively, changes in drinking status predicted 5-year changes in blood pressure among the 652 women and 318 men who satisfied all inclusion criteria for the longitudinal analyses. In multivariate regression analyses, baseline alcohol consumption was not significantly associated with changes in blood pressure or hypertension incidence (systolic/diastolic blood pressure > or = 160/95 mmHg) by 1993. Change in drinking status, however, was significantly associated with changes in systolic pressure. The systolic pressure increase among individuals who initiated alcohol consumption was 6.2 mmHg (95% confidence interval (CI) 1.1 6.4) greater than abstainers, while that for individuals who reported drinking at both time points was 3.8 mmHg (95% CI 1.3-11.1) greater. Blood pressure increases for persons who discontinued drinking were comparable to those of abstainers. Results were independent of baseline age, body mass index, blood pressure, and sex. Social and economic disadvantage in 1988 was significantly associated with continuation and initiation of alcohol consumption by 1993. PMID- 9366621 TI - Incidence of invasive cancers following squamous cell skin cancer. AB - The authors describe the incidence of new primary cancers among 4,639 cases of squamous cell skin cancer (SCC) diagnosed between 1974 and 1994 in the cancer registries of the Swiss cantons of Vaud and Neuchatel (total person-years at risk = 23,152). Overall, 729 metachronous cancers were observed versus 527.6 expected, corresponding to a standardized incidence ratio (SIR) of 1.4 (95% confidence interval (CI) 1.3-1.5). After exclusion of skin cancers, however, 384 second primary neoplasms were observed versus 397.2 expected (SIR = 1.0). Excesses were observed for cancers of the lip (SIR = 3.1) and lung (SIR = 1.3), for basal cell (SIR = 4.3) and melanomatous skin cancers (SIR = 3.3), and non-Hodgkin's lymphomas (SIR = 1.7). Rates were elevated for cancers of the salivary glands (SIR = 4.3) and for Hodgkin's disease (SIR = 2.7), and, below age 65 years, for cancers of the lung (SIR = 1.6), breast (SIR = 1.5), and prostate (SIR = 1.8), for Hodgkin's disease (SIR = 15.8), as well as for all neoplasms except skin (SIR = 1.2; 95% CI 1.0-1.5). The cumulative risk of basal cell skin cancer reached 17% after 15 years. The authors believe that the excesses for basal cell carcinomas and melanomas of the skin following SCC, and possibly of lymphomas, were likely attributable to common phenotypic characteristics and exposure to UV radiation. The elevated rates of lung cancer are suggestive for a role of tobacco as a cause of squamous cell skin cancer. PMID- 9366622 TI - Relation between very low birth weight and developmental delay among preschool children without disabilities. AB - The authors examined the relation between very low birth weight (VLBW: < 1,500 g) and possible developmental delay (DELAY) in the absence of frank developmental disability among young children. The prevalence of DELAY in a population-based cohort (Missouri resident births born from December 1989 through March 1991) of singleton VLBW children (n = 367) was compared with the prevalence of DELAY among both moderately low birth weight (MLBW: 1,500-2,499 g; n = 553) and normal birth weight (NBW: > or = 2,500 g; n = 555) singleton control children. DELAY was defined by nine measures of performance on the Denver Developmental Screening Test II at a median adjusted age of 15 months (range: 9-34 months). Subjects were asymptomatic for disabling conditions at developmental follow-up. Apparently well VLBW children were consistently at greater risk for both moderate and severe measures of DELAY and for DELAY across four functional areas than were either the MLBW (adjusted odds ratios: 1.4-2.7) or NBW children (adjusted odds ratios: 2.1 6.3). The greatest prevalence of DELAY tended to be among appropriate-for gestational age VLBW children who were also the most premature. This study supports developmental follow-up of nondisabled VLBW children because of the significantly elevated risk for DELAY among apparently normal infants. PMID- 9366623 TI - Air pollution and mortality in Philadelphia, 1974-1988. AB - Analyses involving data from many locations throughout the world have now been conducted to assess the association between air pollution and mortality. To date, six independent analyses of mortality data for Philadelphia, Pennsylvania, have been reported. In this new analysis of Philadelphia data for 1974-1988, Poisson regression models were developed to estimate the increased risk of daily mortality associated with air pollution while controlling for longer-term time trends and season and for weather. Model development was based on prior understanding of the effects of these factors on mortality and on consideration of model fit. The authors found moderate correlations of daily concentrations of total suspended particles (TSP), sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO), and only slight correlations of ozone (O3) with other pollutants. When included individually in the model, the means of current and previous days' levels of TSP, SO2, and O3 had statistically significant effects on total mortality; pollutant increases of an interquartile range (34.5 micrograms/m3, 12.9 ppb, and 20.2 ppb, respectively) were associated with increases in mortality of around 1% for TSP and SO2, and of around 2% for O3. The effects of TSP and SO2 were diminished when both pollutants were simultaneously included in the model, whether pairwise or in the full multi-pollutant model. These analyses confirm the association between TSP and mortality found in previous studies in Philadelphia and show that the association is robust to consideration of other pollutants in the model. PMID- 9366624 TI - Can we measure prior postmenopausal estrogen/progestin use? The Postmenopausal Estrogen/Progestin Interventions Trial. The PEPI Investigators. AB - The objective of this study was to assess: 1) the accuracy of a single self report question about postmenopausal estrogen use; and 2) the performance and repeated measures agreement of a standardized hormone use interview. Women (n = 863) in the Postmenopausal Estrogen/Progestin Interventions Trial (PEPI) completed a self-report baseline questionnaire (BQ) at enrollment and a History of Hormone Use interview (HHU) at the 3-month follow-up visit (HHU3mos). A subsample of 101 women completed a second HHU interview 3 years later (HHU3yrs). As determined by the HHU3mos, 479 (56%) of women had ever used postmenopausal estrogen and 261 (30%) had ever used postmenopausal progestin. The mean number of years since last estrogen or progestin use was 2.2 and 1.3 years, respectively. Overall, there was 95% agreement between self-reported estrogen use on the BQ and the HHU3mos (kappa = 0.91). Using the HHU3mos as the criterion standard, the BQ misclassified 2.3% of women as false positives and 6.3% as false negatives. The average duration of estrogen use in the false-negative classifications was 1.9 years (range: 1-9 years). On the HHU3mos, 39.7% of participants could not recall at least one of the specific details of estrogen use (preparation, dose, route, or starting or stopping year); similar patterns of recall were found for progestin use. Factors associated with discordant reporting of ever-use of ERT (BQ vs. HHU3mos) or incomplete reporting of estrogen/progestin use on the HHU3mos were: route of administration, recency of hormone use, duration of hormone use, and race. Age, years since menopause, education, income, and hysterectomy status were not related to discordant and/or incomplete reporting. Agreement between the HHU3mos and HHU3yrs for ever-use of estrogen was 85.2% (kappa = 0.71). In sum, a single self-report question was adequate to ascertain ever-use of postmenopausal estrogen. When a structured interview form was used, details of postmenopausal estrogen and progestin use were not well remembered. Some features of hormone use and participant characteristics were associated with completeness of recalled hormone use, which suggests the potential for differential misclassification. PMID- 9366625 TI - Reliability of reported age at menopause. AB - Age at menopause is an important epidemiologic characteristic whose reliability of reporting in the US population is not known. The authors examined four hypotheses about the reliability of reported age at menopause in the United States: 1) women with hysterectomy-induced menopause more reliably report their age at menopause than women who have undergone natural menopause; 2) reliability declines with time since menopause; 3) reliability declines with age; and 4) women with higher educational levels report their age at menopause more reliably than women with less education. The authors used linear regression models among 2,545 women in the First National Health and Nutrition Examination Survey and Followup Study (1971-1984) and compared responses at first and follow-up interviews. Among women who had undergone a natural menopause, 44% reported their age at menopause within one year from the first to second interviews; among women who had undergone a hysterectomy-induced menopause, 59% reported their age at menopause within one year from first to follow-up interviews. Only hysterectomy status and years from menopause to follow-up interview were significantly associated with the absolute difference between age at menopause reported at first and follow-up interviews. The authors conclude that caution in studies involving age at menopause may enhance our understanding of this critical event in the lives of women. PMID- 9366627 TI - Re: "Perineal powder exposure and the risk of ovarian cancer". PMID- 9366628 TI - Re: "Assessing the direction of causality in cross-sectional studies". PMID- 9366629 TI - Re: "The failure of academic epidemiology: witness for the prosecution". PMID- 9366626 TI - Risk factors for diarrheal duration. AB - To identify child feeding behavior and household hygiene practices that are risk factors for prolonged diarrheal illness, a longitudinal community study was conducted over a 14-month period among 920 children aged 3-37 months who lived in an urban slum settlement in Nairobi, Kenya. Morbidity surveillance was done by home visits every third day in the absence of diarrhea and daily during diarrheal illness until termination of the episode. In-home observations were made to characterize maternal hygiene, cooking, and child feeding practices. Overall, 1,496 episodes of diarrhea were detected. The average diarrheal incidence was 3.5 episodes/child-year, and the incidence of diarrhea > 14 days was 3 episodes/100 child-years. Cox regression was used to examine the independent effects of covariates on time to recovery from a diarrheal episode. Adjusted behavioral factors that were observed to influence recovery from diarrhea included: uncovered water containers (rate ratio (RR) = 0.77, 95% confidence interval (CI) 0.64-0.94); giving no fluids (as opposed to oral rehydration solutions (ORS)/sugar salt solutions (SSS)) (RR = 1.42, 95% CI 1.14-1.77); and administration of diluted cow's milk during the first 3 days of an episode (RR = 1.23, 95% CI 1.00-1.52). These associations remained significant after adjusting for diarrheal severity. The authors recommend, among other measures, improvement of water storage and promotion of continued feeding with cereal-milk mix during diarrhea. PMID- 9366631 TI - Anniversary--a time for reflection. PMID- 9366630 TI - Why history? PMID- 9366632 TI - Annotation: racism resurgent--building a bridge to the 19th century. PMID- 9366633 TI - Eugenics and public health in American history. AB - Supporters of eugenics, the powerful early 20th-century movement for improving human heredity, often attacked that era's dramatic improvements in public health and medicine for preserving the lives of people they considered hereditarily unfit. Eugenics and public health also battled over whether heredity played a significant role in infectious diseases. However, American public health and eugenics had much in common as well. Eugenic methods often were modeled on the infection control techniques of public health. The goals, values, and concepts of disease of these two movements also often overlapped. This paper sketches some of the key similarities and differences between eugenics and public health in the United States, and it examines how their relationship was shaped by the interaction of science and culture. The results demonstrate that eugenics was not an isolated movement whose significance is confined to the histories of genetics and pseudoscience, but was instead an important and cautionary part of past public health and a general medical history as well. PMID- 9366634 TI - Under the shadow of Tuskegee: African Americans and health care. AB - The Tuskegee Syphilis Study continues to cast its long shadow on the contemporary relationship between African Americans and the biomedical community. Numerous reports have argued that the Tuskegee Syphilis Study is the most important reason why many African Americans distrust the institutions of medicine and public health. Such an interpretation neglects a critical historical point: the mistrust predated public revelations about the Tuskegee study. This paper places the syphilis study within a broader historical and social context to demonstrate that several factors have influenced--and continue to influence--African American's attitudes toward the biomedical community. PMID- 9366635 TI - Engendering the dread disease: women, men, and cancer. AB - This paper, based on an analysis of cancer articles published in popular periodical literature since the early part of the century, argues that gender has played a key role in medical and popular understandings of cancer. Cancer education, the author finds, has taught women and men different things. Public health materials created with the intention of improving health through education actually send a multiplicity of messages, not all of them helpful. This essay suggests that public health messages targeted by sex are problematic, although perhaps necessary. The paper also contributes to scholarship concerned with the question of how people develop their ideas about risk of disease. PMID- 9366636 TI - Shifting categories of the social harms associated with alcohol: examples from late medieval and early modern England. AB - This paper offers a historical perspective on our own attempts to define the social harms associated with the abuse of alcohol. Challenging the notion that categories are necessarily objective and constant, it instead emphasizes the extent to which even harms that are visible and thus susceptible to measurement are in fact socially constructed. English sources from the preindustrial era revealed six broad categories of social harms associated with the abuse of alcohol. Four of the categories consisted of visible harms in the form of income lost, domestic violence, brawling, and accidents, all of which are still recognized as social harms associated with the abuse of alcohol. The other two categories, reversal of the established moral order and susceptibility to trickery, were of an essentially intrinsic or subjective nature and have since dropped from the lexicon of social harms. PMID- 9366637 TI - The image and advocacy of public health in American caricature and cartoons from 1860 to 1900. AB - The decades just before and after the founding of the American Public Health Association in 1872 saw an efflorescence of political cartooning and caricature in national-circulation weeklies. Part of the political and social critique that cartoonists and their editors provided the public focused on needs or opportunities for preventing illness and accidents. This paper presents a small selection of editorial cartoons that agitated in support of public health activities over 4 decades. The goals are to illustrate several concerns that rose to national prominence in that era, to examine the kinds of imagery that newspapers and magazine editors offered their readers, and to observe how frequently the public was encouraged to see politicians and commercial interests as responsible for preventable health problems. This discussion focuses exclusively on propagandistic images, leaving aside the reportorial depictions of events in the news and the neutral illustrations of methods and machines in scientific and technical publications. PMID- 9366638 TI - Taking the cure to the poor: patients' responses to New York City's tuberculosis program, 1894 to 1918. AB - Drawing on the case files of a major charitable agency, this paper explores how poor people experienced New York City's pioneering program of tuberculosis control. Although the program provided enormous benefits, poor New Yorkers often had pressing concerns that took priority over eradicating tuberculosis. Moreover, the program imposed extreme hardships even as it promised liberation from a terrible scourge. Poor people did not protest collectively, but many individually resisted. They delayed seeking diagnosis, disobeyed the advice promulgated by the Department of Health, attended clinics irregularly, and either refused to enroll in hospitals, sanatoria, and preventoria or fled soon after arrival. PMID- 9366639 TI - The Junior Red Cross goes to Healthland. AB - An amusing reminder of earnest attempts to teach the principles of public health, Junior Red Cross Time brought plays and games about "Healthland" to schoolchildren in the 1920s. Explaining why health education became part of the mission of the Junior Red Cross raises larger issues, such as the ideology and practice of the American Red Cross in war and peace, the place of health in the moral education of children, and the transition from the activism of the Progressive Era to the markedly different social climate of the 1920s. The Junior Red Cross promoted Healthland largely because it was an innocuous concept that had been stripped of potentially controversial features to adapt it to the conservative mood of postwar America. This process of dilution mirrored the fate of the adult Red Cross, which briefly and unsuccessfully sought to reinvent itself as a national (and international) agency for the promotion of public health. The unreality of Healthland is no mere coincidence; its separation from the real world was a crucial part of its appeal to the Red Cross in the 1920s. PMID- 9366641 TI - The House of Falk: the paranoid style in American health politics. AB - The onset of the Cold War had a blighting effect on the campaign for a national health insurance program in the United States. In the highly charged atmosphere of the late 1940s, proponents of social insurance spent considerable time and energy denying that they were agents of foreign powers. In one widely promoted conspiratorial formulation, some on the right traced the origins of subversion not only to Moscow but also to Geneva, Switzerland, home of the International Labor Organization. In the fractiously partisan context of the period, conservative political leaders amplified concerns over disloyal bureaucrats' manipulating the levers of legislative politics as well as the design of health policy. One federal official in particular, I. S. Falk, became the object of outright demonization. The paranoid attacks took their toll on the drive to extend social protection. The reformers' difficulties suggest the limitations of heavy dependence on bureaucratic expertise in the pursuit of health security. PMID- 9366640 TI - Discovering environmental cancer: Wilhelm Hueper, post-World War II epidemiology, and the vanishing clinician's eye. AB - Today, our understanding of and approach to the exogenous causes of cancer are dominated by epidemiological practices that came into widespread use after World War II. This paper examines the forces, considerations, and controversies that shaped postwar risk factor epidemiology in the United States. It is argued that, for all of the new capabilities it brought, this risk factor epidemiology has left us with less of a clinical eye for unrecognized cancer hazards, especially from limited and localized exposures in the work-place. The focus here is on Wilhelm Hueper, author of the first textbook on occupational cancer (1942). Hueper became the foremost spokesman for earlier identification practices centering on occupational exposures. The new epidemiological methods and associated institutions that arose in the 1940s and 1950s bore an unsettled relation to earlier claims and methods that some, Hueper among them, interpreted as a challenge. Hueper's critique of the new epidemiology identified some of its limitations and potentially debilitating consequences that remain with us today. PMID- 9366642 TI - Race, foster care, and the politics of abandonment in New York City. AB - Following the end of the Great Depression of the 1930s, the sectarian system of foster care services in New York City practiced open discrimination. African American children were generally segregated in a small number of overcrowded and understaffed all-Black institutions. As the African-American migration to the city accelerated in the years following the outbreak of World War II, a small group of psychologists, jurists, philanthropists, and social workers began a systematic challenge to this system. This paper explores the role of racism in shaping New York's foster care system and the experience of African-American children who were forced to depend on services originally organized to serve Whites. It also looks at the ways race affected the way children were typed--as mentally ill, delinquent, or even criminal--in response to the structural realities of a system that sorted children into separate types of institutions according to race. The paper also provides the background for understanding the landmark challenge to segregation of children in sectarian and public institutions represented by Wilder v Sugarman. PMID- 9366643 TI - The federal government's use of Title VI and Medicare to racially integrate hospitals in the United States, 1963 through 1967. AB - Explicit discrimination against minorities existed in the 1960s in hospital patient admissions and physician and nurse staff appointments. With passage of the Civil Rights Act of 1964, along with Medicare legislation in 1965, civil rights advocates within the federal government had both a legislative mandate to guarantee equal access to programs funded by the federal government in Title VI and a federal program that affected every hospital in the country in Medicare. This study was conducted to determine the extent to which the Medicare hospital certification program was a major determinant in the racial integration of hospitals throughout the United States. In-depth interviews were conducted with individuals involved in hospital and health care policy in the 1950s and 1960s. Other primary resources include archival and personal manuscripts, government documents, newspapers, and periodicals. PMID- 9366644 TI - Public health on the railroad: William Freeman Snow and the California Sanitation Exhibit. AB - This paper describes the California Sanitation Exhibit, a railroad car outfitted for instruction in public health that toured California in 1909 and 1910. The sanitation exhibit used display models, photographs, and lectures to educate the public about tuberculosis and other infectious diseases, waste contamination, and the dangers of bad milk. The success of the exhibit, which reached 5% of the state's population, resulted in the appointment of its creator, William Freeman Snow, as secretary of the California State Board of Health. PMID- 9366645 TI - Labor Insurance. 1904. PMID- 9366646 TI - Nicotine content of the eclipse nicotine delivery device. PMID- 9366647 TI - Emergency department costs. PMID- 9366648 TI - The quality of data reported on birth certificates. PMID- 9366649 TI - Ethical and health implications of directive counseling on long-acting contraception. PMID- 9366650 TI - Directive counseling should emphasize disease protection not pregnancy prevention. PMID- 9366651 TI - Trends in overweight and obesity among Italian adults, 1983 through 1994. PMID- 9366652 TI - Mortality of persons with mental retardation in institutions and in the community. PMID- 9366653 TI - Racism and lead poisoning. PMID- 9366654 TI - The clinical course of unipolar major depressive disorders. PMID- 9366655 TI - Natural history of Diagnostic Interview Schedule/DSM-IV major depression. The Baltimore Epidemiologic Catchment Area follow-up. AB - BACKGROUND: Natural history can be characterized by incidence, recurrence, and duration of episodes. Research on the incidence of major depression is rare; studies of recurrence and duration are limited to clinical samples. METHODS: The Baltimore, Md, site of the Epidemiologic Catchment Area Program followed up its 1981 baseline cohort of 3481 respondents with an additional assessment in 1993 to 1996. Interviews were obtained from 1920 respondents (73% of the survivors). The Diagnostic Interview Schedule and the same survey procedures as in 1981 were used, augmented with a Life Chart Interview for dating the onset and duration of syndromes. RESULTS: There were 71 new cases of Diagnostic interview Schedule/DSM IV major depression and 23,698 person-years of exposure, generating an estimated incidence of 3.0 per 1000 per year. Incidence peaked while subjects were in their 30s, with a smaller peak when they were in their 50s. Prodromal symptoms often occurred many years before the full criteria for diagnosis were met. Women were at higher risk for becoming new cases but had neither higher risk for recurrence nor longer episodes than men. Episodes of depression lasted for 12 weeks. The duration of an episode, and time to an episode-free year, was longer in the first episode than in recurrent episodes. CONCLUSIONS: The incidence estimated in this study is consistent with that found in the few other similar studies performed. The bimodality of onset suggests the value of further exploring the heterogeneity of depression via its natural history. Reported differences in prevalence between men and women seem to be due to differences in incidence, not chronicity. PMID- 9366656 TI - Recovery from major depression. A 10-year prospective follow-up across multiple episodes. AB - BACKGROUND: Major depressive disorder is often marked by repeated episodes of depression. We describe recovery from major depression across multiple mood episodes in patients with unipolar major depression at intake and examine the association of sociodemographic and clinical variables with duration of illness. METHODS: A cohort of 258 subjects treated for unipolar major depressive disorder was followed up prospectively for 10 years as part of the Collaborative Depression Study, a multicenter naturalistic study of the mood disorders. Diagnoses were made according to the Research Diagnostic Criteria, and the course of illness was assessed with the Longitudinal Interval Follow-up Evaluation. Survival analyses were used to calculate the duration of illness for the first 5 recurrent mood episodes after recovery from the index episode. RESULTS: Diagnosis remained unipolar major depressive disorder for 235 subjects (91%). The median duration of illness was 22 weeks for the first recurrent mood episode, 20 weeks for the second, 21 weeks for the third, and 19 weeks for the fourth and fifth recurrent mood episodes; the 95% confidence intervals were highly consistent. From one episode to the next, the proportion of subjects who recovered by any one time point was similar. For subjects with 2 or more recoveries, the consistency of duration of illness from one recovery to the next was low to moderate. None of the sociodemographic or clinical variables consistently predicted duration of illness. CONCLUSION: In this sample of patients treated at tertiary care centers for major depressive disorder, the duration of recurrent mood episodes was relatively uniform and averaged approximately 20 weeks. PMID- 9366657 TI - Treatment of major depression with psychotherapy or psychotherapy-pharmacotherapy combinations. AB - BACKGROUND: Few reliable correlates of treatment response in depression have emerged despite nearly 40 years of research. We examined the correlates of recovery in a "mega-analysis," or meta-analysis of original data, of 595 patients with major depressive disorder enrolled in 6 standardized treatment protocols. METHODS: All patients (mean age, 44 years; 31% male and 69% female) met criteria for nonbipolar, nonpsychotic primary major depressive disorder and were treated for 16 weeks with either cognitive behavior therapy or interpersonal psychotherapy alone (psychotherapy alone; n = 243) or interpersonal psychotherapy plus antidepressant pharmacotherapy (combined therapy; n = 352). The impact of treatment type, severity, study, and other covariates on recovery rates or time to recovery were examined by means of chi 2, log-rank tests, the Cox proportional hazards model, and sensitivity analyses. RESULTS: Whereas combined therapy was not significantly more effective than psychotherapy alone in milder depressions, a highly significant advantage was observed in more severe recurrent depressions. Poorer outcomes were also observed in women and older patients, although these effects were dependent on inclusion of particular studies. CONCLUSIONS: Mega analysis is a powerful method for comparing the efficacy of treatments and examining correlates of response. Using this method, we found new evidence in support of the widespread clinical impression that combined therapy is superior to psychotherapy alone for treatment of more severe, recurrent depressions. PMID- 9366658 TI - Temporal profiles of the course of depression during treatment. Predictors of pathways toward recovery in the elderly. AB - BACKGROUND: Predictors of treatment response and recovery from depression in late life remain poorly understood. Previous studies have focused on a narrow range of response and recovery variables; namely, whether patients achieve or do not achieve a defined outcome or time to achieve the outcome. Whether patients vary in their pathways toward those outcomes--and the extent to which such variation can be anticipated by patient characteristics prior to treatment--has not been empirically examined. METHODS: Depression symptom levels were monitored for 18 weeks in 95 persons aged 60 years or older who were experiencing a recurrence of major depression. Subjects received standardized combined nortriptyline treatment and interpersonal psychotherapy throughout the period. Cluster analysis was used to identify depression recovery patterns. Multivariate analyses considered whether recovery patterns were predicted by pretreatment psychosocial, clinical, and electroencephalographic sleep characteristics. RESULTS: Four subgroups of elders were identified who differed in rate, stability, and direction of recovery, ie, those showing (1) rapid sustained improvement, (2) delayed but sustained improvement, (3) partial or mixed response, or (4) no response. Pretreatment characteristics reliably predicted subjects' group membership. Higher levels of acute and chronic stressors, poorer social supports, younger age at first depressive episode, endogenous depression, higher current anxiety, older current age, and poorer subjective and objective (electroencephalographic) sleep predicted poorer response profiles. CONCLUSIONS: There are multiple pathways by which individuals begin to emerge from depression; these pathways can be identified empirically. Variables from diverse psychobiologic domains can be used to predict which persons are likely to advance along which trajectories toward recovery. PMID- 9366659 TI - Family and individual therapy in anorexia nervosa. A 5-year follow-up. AB - BACKGROUND: There is evidence that specific psychological treatments are effective in patients with eating disorders. Our goal was to determine by means of a controlled trial whether psychological treatments, previously found to be effective in anorexia nervosa, gave rise to enduring benefits. METHODS: A 5-year follow-up was conducted on patients who had participated in a previous trial of family therapy for anorexia and bulimia nervosa. Family therapy or individual supportive therapy had been administered to 80 outpatients for 1 year beginning on discharge from hospital after weight restoration. The 80 patients had been subdivided into 4 prognostically homogeneous groups of which 2 turned out to be the most important: patients with early onset and short history of anorexia nervosa, and patients with late-onset anorexia nervosa. At the 5-year follow-up, the efficacy of the outpatient therapies was again assessed by the maintenance of weight, and the categories of general outcome and dimensions of clinical functioning defined by the Morgan-Russell scales. RESULTS: Significant improvements were found in the group of 80 patients as a whole, mainly attributable to the natural outcome of anorexia nervosa, and most evident in the early onset and short history group, as expected. Within 2 of the prognostic groups, significant benefits attributable to previous psychological treatments were still evident, favoring family therapy for patients with early onset and short history of anorexia nervosa and favoring individual supportive therapy for patients with late-onset anorexia nervosa. CONCLUSIONS: Much of the improvements found at a 5-year follow-up can be attributed to the natural outcome of the illness. Nevertheless, it was still possible to detect long-term benefits of psychological therapies completed 5 years previously. PMID- 9366660 TI - A double-blind, randomized, placebo-controlled trial of fluoxetine in children and adolescents with depression. AB - BACKGROUND: Depression is a major cause of morbidity and mortality in children and adolescents. To date, randomized, controlled, double-blind trials of antidepressants (largely tricyclic agents) have yet to reveal that any antidepressant is more effective than placebo. This article is of a randomized, double-blind, placebo-controlled trial of fluoxetine in children and adolescents with depression. METHODS: Ninety-six child and adolescent outpatients (aged 7-17 years) with nonpsychotic major depressive disorder were randomized (stratified for age and sex) to 20 mg of fluoxetine or placebo and seen weekly for 8 consecutive weeks. Randomization was preceded by 3 evaluation visits that included structured diagnostic interviews during 2 weeks, followed 1 week later by a 1-week, single-blind placebo run-in. Primary outcome measurements were the global improvement of the Clinical Global Impressions scale and the Children's Depression Rating Scale--Revised, a measure of the severity depressive symptoms. RESULTS: Of the 96 patients, 48 were randomized to fluoxetine treatment and 48 to placebo. Using the intent to treat sample, 27 (56%) of those receiving fluoxetine and 16 (33%) receiving placebo were rated "much" or "very much" improved on the Clinical Global Impressions scale at study exit (chi 2 = 5.1, df = 1, P = .02). Significant differences were also noted in weekly ratings of the Children's Depression Rating Scale--Revised after 5 weeks of treatment (using last observation carried forward). Equivalent response rates were found for patients aged 12 years and younger (n = 48) and those aged 13 years and older (n = 48). However, complete symptom remission (Children's Depression Rating Scale--Revised < or = 28) occurred in only 31% of the fluoxetine-treated patients and 23% of the placebo patients. CONCLUSION: Fluoxetine was superior to placebo in the acute phase treatment of major depressive disorder in child and adolescent outpatients with severe, persistent depression. Complete remission of symptoms was rare. PMID- 9366661 TI - A randomized trial of assertive community treatment for homeless persons with severe mental illness. AB - BACKGROUND: This experiment evaluated the effectiveness of an innovative program of assertive community treatment (ACT) for homeless persons with severe and persistent mental illnesses. METHODS: One hundred fifty-two homeless persons with severe and persistent mental illness were randomized to either the experimental ACT program or to usual community services. Baseline assessments included the Structured Clinical Interview for DSM-III-R, Quality-of-Life Interview, Colorado Symptom Index, and the Medical Outcomes Study 36-Item Short Form Health Survey. All assessments (except the Structured Clinical Interview) were repeated at the 2 , 6-, and 12-month follow-up evaluations. RESULTS: Subjects in the ACT program used significantly fewer psychiatric inpatient days, fewer emergency department visits, and more psychiatric outpatient visits than the comparison subjects. The ACT subjects also spent significantly more days in stable community housing, and they experienced significantly greater improvements in symptoms, life satisfaction, and perceived health status. CONCLUSIONS: Relative to usual community care, the ACT program for homeless persons with severe and persistent mental illness shifts the locus of care from crisis-oriented services to ongoing outpatient care and produces better housing, clinical, and life satisfaction outcomes. PMID- 9366662 TI - Sex differences in posttraumatic stress disorder. AB - BACKGROUND: Epidemiologic surveys in the general population documented a higher rate of posttraumatic stress disorder (PTSD) in women than in men. To date, the finding has received little scientific attention. This study examines the extent to which sex differences in PTSD might be explained by previously identified risk factors and whether the sex difference in PTSD varied by age at exposure to traumatic events. METHODS: The NIMH-DIS (NIMH Diagnostic Interview Schedule, Version III Revised) was used to measure DSM-IIIR disorders in a random sample of 1007 young adults. Cox proportional hazards models were used to estimate changes in the hazards ratio for PTSD associated with sex when potential risk factors were included. RESULTS: Lifetime prevalence of exposure to traumatic events and number of traumatic events did not vary by sex. The prevalence of PTSD was higher for women than for men exposed to traumatic events (hazards ratio, 2.3; 95% confidence interval, 1.5-3.6). Preexisting anxiety disorders or major depressive disorders played a part in the observed sex difference in PTSD. Family history of anxiety disorder and early separation from parents, although significant risk factors for PTSD in subjects of both sexes, were unrelated to the sex difference in PTSD. The sex difference in PTSD was markedly greater if exposure occurred in childhood than later on. CONCLUSIONS: Posttraumatic stress disorder is more likely to develop in females than in males after exposure to a traumatic event. Susceptibility to PTSD in females might be greater in childhood than after age 15 years. Explanations of the sex difference might involve characteristics of individuals and of the traumatic experiences. PMID- 9366664 TI - Impression cytology study of epithelial phenotype of ocular surface reconstructed by preserved human amniotic membrane. AB - OBJECTIVE: To determine the epithelial phenotype of the ocular surface reconstructed by preserved human amniotic membrane. METHODS: Impression cytology was performed in 6 patients who received a large patch of amniotic membrane for conjunctival surface reconstruction during removal of acquired melanosis, conjunctival intraepithelial neoplasia, or bilateral inferior conjunctival chalasis, or for corneal surface reconstruction during removal of pannus associated with limbal deficiency caused by aniridia, toxic epidermal necrolysis, or chemical burn. RESULTS: The nongoblet epithelial cells covering the amniotic membrane were uniformly smaller and the cell density was almost twice that of age and sex-matched normal control eyes at the corresponding site, and the goblet cell density was almost 10 times that of the control (both P < .05; Student paired t test) (N = 7 eyes). Furthermore, the conjunctival epithelial phenotype with goblet cells was found on corneal surfaces of all 3 patients with limbal deficiency. CONCLUSIONS: The success of conjunctival surface reconstruction correlated well with recovery of the conjunctival epithelial phenotype. The lack of corneal epithelial phenotype even on an avascular corneal stroma supports the concept that conjunctival transdifferentiation does not occur in vivo, and indicates that additional limbal stem cell transplantation is needed for effective corneal surface reconstruction in patients with limbal deficiency. PMID- 9366663 TI - A 'second life' agenda. Psychiatric research issues raised by protease inhibitor treatments for people with the human immunodeficiency virus or the acquired immunodeficiency syndrome. AB - Seldom in the history of medicine has an entire generation of patients with an incurable, progressive, and ultimately fatal disease suddenly been offered the prospect of extended survival and even, perhaps, a "second life." The relatively simultaneous appearance of 2 major treatment developments has created profound changes in therapeutic options and outlook. The first development is an assay of serum levels of human immunodeficiency virus viral copies, providing a critical tool for clinical decision making. The second is the marketing between December 1995 and April 1997 of 4 human immunodeficiency virus protease inhibitors that, combined with previously available antiviral medications, achieve a new level of efficacy. With the advent of these changes come multiple psychiatric research and policy issues. These include the development of strategies to establish and maintain medication adherence. This is a critical task, given the complexity of combination therapy regimens and the rapid onset of viral resistance to protease inhibitors within days to weeks of missed or suboptimal dosing. The psychological issues to be studied include the process of restructuring lives and expectations in the event of clinical benefit or managing the distress associated with clinical failure. Other research questions include the effects of restored health on the appraisal of human immunodeficiency virus risk behaviors, assessment of effect of neurocognitive functioning, and unanswered questions about psychotropic or protease inhibitor drug interactions due to their shared metabolic pathways. Behavioral scientists can inform provision of care to patients who may be considered difficult to treat, such as those with severe and persistent mental illness or active substance abuse or the homeless. This includes the provision of empirical data regarding individual and situational characteristics that are likely to promote or impede adherence, as well as innovative provision systems. Psychiatry can make notable contributions during this turning point in human immunodeficiency virus therapeutics and research. PMID- 9366665 TI - Comparison of dorzolamide and timolol as suppressors of aqueous humor flow in humans. AB - OBJECTIVES: To measure the effectiveness of topical 2% dorzolamide hydrochloride (Trusopt, Merck & Co Inc, Whitehouse Station, NJ) as a suppressor of aqueous humor flow in the human eye as compared with the effectiveness of 0.5% timolol maleate (Timoptic, Merck & Co Inc) and to measure the additivity of the 2 drugs. DESIGN: A randomized, double-masked, placebo-controlled study of 40 human subjects was carried out in 2 academic centers (Mayo Clinic, Rochester, Minn, and University of Uppsala, Uppsala, Sweden). The rate of aqueous flow was measured from 8 AM to 4 PM by means of fluorophotometry after administration of doses of each drug singly and both drugs together. RESULTS: Dorzolamide reduced aqueous flow from 3.07 +/- 0.63 microL/min (mean +/- SD) to 2.53 +/- 0.60 microL/min, a reduction of 18% (P < .001). Timolol reduced aqueous flow from the same beginning rate to 1.64 +/- 0.35 microL/min, a reduction of 47% (P < .001). The inhibitory effect of timolol was 2.6 times the inhibitory effect of dorzolamide (P < .001). The 2 drugs were almost completely additive, and together reduced the flow to 1.37 +/- 0.33 microL/min, a reduction of 55%. Consistent effects were observed on intraocular pressure. CONCLUSIONS: Timolol is more effective than dorzolamide as a suppressor of aqueous humor flow in the normal human eye. Timolol and dorzolamide are additive in their effects, both on aqueous flow and intraocular pressure. PMID- 9366666 TI - Temporal corneal phacoemulsification in patients with filtered glaucoma. AB - OBJECTIVE: To evaluate the effect of temporal clear corneal phacoemulsification on intraocular pressure (IOP) in eyes that underwent prior trabeculectomy. DESIGN: Retrospective case-control study. PATIENTS: Forty consecutive patients who underwent temporal clear corneal phacoemulsification subsequent to trabeculectomy (trabeculectomy-phacoemulsification group) were identified, and 40 control patients who underwent trabeculectomy alone (trabeculectomy group) were matched to the case patients for length of follow-up, age, IOP, number of antiglaucoma medications, number of 5-fluorouracil injections, race, sex, and diagnosis. MAIN OUTCOME MEASURES: Intraocular pressure before vs 1 year after phacoemulsification in the trabeculectomy-phacoemulsification group compared with IOP in the trabeculectomy group and survival analysis of IOP control after trabeculectomy in the 2 groups. RESULTS: In the trabeculectomy phacoemulsification group, IOP 1 year after phacoemulsification was not significantly different from the prephacoemulsification IOP value (P = .65). Kaplan-Meier survival analysis showed that the rates of IOP control 3, 6, and 9 years after trabeculectomy in the trabeculectomy-phacoemulsification group were 80%, 66%, and 44%, respectively; in the trabeculectomy group, these were 79%, 69%, and 55%, respectively. These survival curves were not statistically different (P = .55). CONCLUSION: Cataract surgery by temporal clear corneal phacoemulsification in eyes with filtering blebs after trabeculectomy does not adversely affect long-term IOP control. PMID- 9366667 TI - Macular hole opercula. Ultrastructural features and clinicopathological correlation. AB - OBJECTIVE: To investigate the ultrastructural features of idiopathic full thickness macular hole (FTMH) opercula excised during vitrectomy and to correlate them with the outcome of surgery. METHODS: Opercula were collected from eyes undergoing vitrectomy for stage 3 FTMH using noncrushing, cupped foreign body forceps. Following immediate fixation, specimens were processed for transmission electron microscopy. The ultrastructural features were correlated with the clinical data recorded for each patient before and after surgery. RESULTS: Eighteen specimens were studied. Native vitreous collagen was identified on the surface of all 18, while fragments of internal limiting membrane were present in 11 (61%). Eleven (61%) were found to contain only glia, comprising fibrous astrocytes and Muller cells in variable proportions. The remaining 7 (39%) were found to contain, in addition to glia, neurites and synaptic complexes, of which some were typical of cone photoreceptors. The initial surgical closure rate was significantly better in eyes in which only glia were present (9/11 [82%]), compared with those with neurites (1/7 [14%]) (P = .01). Once closure had been achieved with reoperation, the median final visual acuity was 20/60 in both groups (P = .26), although the likelihood of achieving an acuity of 20/40 or better was greater in the former (50%) than the latter group (17%). CONCLUSIONS: Two distinct types of opercula occur in association with stage 3 FTMH--those containing only glia (pseudo-opercula), which are probably associated with a foveal dehiscence and little or no loss of foveal tissue, and those containing both glia and a significant number of avulsed foveal cones (true opercula), which arise from a full-thickness foveal tear. Although the loss of foveal tissue in true opercula would seem to explain the worse initial anatomical and more modest visual results in some eyes, significant visual improvement may still be achieved after successful closure. The presence of neurites in true opercula suggests that, in at least some cases, direct traction on the foveal retina leads to macular hole formation. PMID- 9366668 TI - Ganciclovir implant exchange. Timing, surgical procedure, and complications. AB - BACKGROUND: The ganciclovir implant is effective for the treatment of cytomegalovirus (CMV) retinitis. The device eventually runs out of drug, however, and must be replaced. We report our experience with exchanging ganciclovir implants during the course of a randomized clinical trial. METHODS: During our study, patients with newly diagnosed peripheral CMV retinitis were treated with a ganciclovir implant. The implant was scheduled for exchange at 32 weeks. It was exchanged earlier if progression of CMV retinitis occurred. Patient examinations and standard fundus photography were performed at 2-week intervals after the exchange procedure. RESULTS: Twenty-six exchange procedures were performed. Twenty-two eyes in 15 patients received a second implant and 4 eyes in 4 patients later received a third implant. Cytomegalovirus retinitis was rendered or maintained inactive in 22 of 23 cases with more than 1 month of follow-up after the second or third implants. Complications after the second implant procedure included transient vitreous hemorrhage in 5 eyes, postoperative inflammation in 1 eye, and retinal detachment in 1 eye. Median visual acuity returned to 20/25 by 28 days and to 20/20 by 42 days. Complications after the third implant procedure included dense vitreous hemorrhage in 3 of 4 eyes. Median survival time after a second implant procedure was 89 days. CONCLUSIONS: The initial ganciclovir implant exchange procedure is well tolerated with continued long-term control of CMV retinitis. Multiple reentries through the same wound may be associated with an increased risk for vitreous hemorrhage. PMID- 9366670 TI - Nonarteritic anterior ischemic optic neuropathy. A case-control study of potential risk factors. AB - OBJECTIVE: To determine the influence of certain potential risk factors on the occurrence of nonarteritic anterior ischemic optic neuropathy. DESIGN: Case control using 2 independent control groups, one involving a geographically defined population and the other involving patients who underwent a routine comprehensive medical evaluation. SETTING: Multispecialty clinic in a rural setting providing primary, secondary, and tertiary care for residents of central and northern Wisconsin and the Upper Peninsula of Michigan. PATIENTS: Fifty-one patients older than 45 years with first ever acute nonarteritic anterior ischemic optic neuropathy. MAIN OUTCOME MEASURES: Potential risk factors defined using standardized definitions abstracted from the medical records, including diabetes, hypertension, hypercholesterolemia, coronary artery disease, tobacco use, chronic obstructive pulmonary disease, body mass index, hematocrit, and white blood cell count. METHODS: Conditional logistic regression analyses, first using a univariate analysis and then employing a multivariate analysis using a forward selection process. RESULTS: The geographically defined case-control multivariate analysis revealed that diabetes (odds ratio = 2.7, 95% confidence interval = 1.2 6.3, P = .02) and body mass index (odds ratio = 1.07, 95% confidence interval = 1.00-1.14, P = .08) were associated with case status. The comprehensive case control multivariate analysis revealed that only diabetes (odds ratio = 5.0, 95% confidence interval = 1.4-17.3, P = .01) was a significant risk factor. The attributable risk estimation for diabetes was 0.21 and 0.27 for the geographically defined and comprehensive controls, respectively. CONCLUSIONS: Diabetes seems to be a major risk factor for the development of nonarteritic anterior ischemic optic neuropathy. The low attributable risk estimation suggests that factors other than diabetes are important in the development of nonarteritic anterior ischemic optic neuropathy or in predisposing individuals to it. PMID- 9366669 TI - Histopathologic study of eyes after iodine I 125 episcleral plaque irradiation for uveal melanoma. AB - OBJECTIVES: To describe the histopathologic findings attributable to irradiation in eyes with uveal malignant melanoma treated with iodine I 125 brachytherapy and to compare these findings with those reviewed in a previous study that compared histopathologic findings in eyes enucleated after proton beam teletherapy with those seen in eyes in a nonirradiated control group. METHODS: The slides from 22 eyes with uveal melanoma that had undergone enucleation after the administration of 125I brachytherapy were studied. The histopathologic features of the tumor and the retina were graded. Results were compared with findings from a previously reported group of 47 proton beam-treated eyes and its control group. RESULTS: Patient age, time between irradiation and enucleation, and ciliary body involvement were similar for the 125I brachytherapy-treated group and the proton beam-treated group and its control group. This allows comparison of the histopathologic findings. Comparing the 125I brachytherapy- and proton beam treated groups, most histopathologic features were similar with nominally statistically significant differences only for cell type, number of mitotic figures, and fibrous metaplasia of the retinal pigment epithelium adjacent to the tumor. CONCLUSIONS: Irradiation of uveal melanoma induces changes in the tumor and in the surrounding retina. Brachytherapy and charged particle therapy are the 2 principal methods of irradiation. This study demonstrates that similar changes are produced by 125I plaque irradiation and proton beam irradiation. PMID- 9366671 TI - Does optic disc appearance distinguish ischemic optic neuropathy from optic neuritis? AB - OBJECTIVE: To determine whether characteristics of optic nerve swelling assist in distinguishing between optic neuritis and anterior ischemic optic neuropathy. METHOD: Optic nerve stereophotograph review by masked observers. RESULTS: Altitudinal swelling, pallor, arterial attenuation, and hemorrhage are found more commonly in anterior ischemic optic neuropathy than in optic neuritis. CONCLUSION: Optic disc appearance does help to distinguish anterior ischemic optic neuropathy from optic neuritis, although there are overlapping features. PMID- 9366672 TI - Botulinum toxin management of essential infantile esotropia in children. AB - BACKGROUND: Infantile esotropia has an onset during early infancy when visual cortical connections are established for binocular fusion and stereopsis. The goal of early treatment is to achieve normal binocular alignment and a favorable sensory outcome. OBJECTIVE: To determine the long-term effects of the use of botulinum toxin for the management of infantile esotropia in children. PATIENTS: Seventy-six neurologically normal children ranging from 4 to 48 months of age were entered consecutively into the study after being given the initial diagnosis of infantile esotropia with a mean strabismic angle of 33 prism diopters. INTERVENTIONS: Simultaneous bilateral injections of 2.5 U of botulinum toxin type A were made into the medial rectus muscles under nitrous oxide and ethrane anesthesia. Patients were followed up for 12 to 95 months after the last injection. Forty patients required 1 bilateral injection and 36 patients required multiple bilateral injections to achieve a favorable motor outcome. RESULTS: Bilateral medial rectus muscle injections of botulinum toxin were effective in reducing the mean preinjection deviation of 33 PD to an average esotropic angle of 2 PD. Binocular alignment (+/- 10 PD) was achieved in 68 patients (89%). Boys required significantly fewer injections than did girls. The secondary incidence of overacting inferior oblique muscles was significantly greater in boys, while girls had a significantly greater incidence of late-onset refractive errors. CONCLUSION: Botulinum toxin is an effective treatment modality for the management of infantile esotropia in infants and children, producing binocular alignment of the visual axes. PMID- 9366673 TI - Serum sulfotransferase levels in patients with macular corneal dystrophy type I. AB - OBJECTIVE: To measure the levels of sulfotransferase activity for keratan sulfate and chondroitin sulfate in serum of patients with macular corneal dystrophy type I, an inherited disorder that is characterized by the absence of sulfate esters on keratan sulfate in the corneal stroma. METHODS: The amount of sulfur-35 transferred from 3'-phosphoadenosine 5'-phosphosulfate to partially sulfated keratan sulfate and partially sulfated chondroitin sulfate by the sulfotransferase present in serum from patients with macular corneal dystrophy and age-matched controls was determined under conditions where only the added enzyme was rate limiting. RESULTS: Serum from patients with macular corneal dystrophy type I has the same level of sulfotransferase activity for keratan sulfate and chondroitin sulfate as found in age-matched controls. CONCLUSIONS: Patients with macular corneal dystrophy type I have sulfotransferase activity for sulfating at least 1 of the 2 sugars in keratan sulfate. It is proposed that the sulfotransferase for N-acetylglucosamine may be deficient. PMID- 9366674 TI - A comparison of retinal morphology viewed by optical coherence tomography and by light microscopy. AB - OBJECTIVE: To compare the cross-sectional images of primate retinal morphology obtained by optical coherence tomography (OCT) with light microscopy to determine the retinal components represented in OCT images. METHODS: Laser pulses were delivered to the retina to create small marker lesions in a Macaca mulatta. These lesions were used to align in vivo OCT scans and ex vivum histologic cross sections for image comparison. RESULTS: The OCT images demonstrated reproducible patterns of retinal morphology that corresponded to the location of retinal layers seen on light microscopic overlays. Layers of relative high reflectivity corresponded to horizontally aligned retinal components such as the nerve fiber layer and plexiform layers, as well as to the retinal pigment epithelium and choroid. In contrast, the nuclear layers and the photoreceptor inner and outer segments demonstrated relative low reflectivity by OCT. CONCLUSIONS: Retinal morphology and macular OCT imaging correlate well, with alignment of areas of high and low reflectivity to specific retinal and choroidal elements. Resolution of retinal structures by OCT depends on the contrast in relative reflectivity of adjacent structures. Use of this tool will enable expanded study of retinal morphology, both normal and pathologic, as it evolves in vivo. PMID- 9366676 TI - Incidence of acute primary angle-closure glaucoma in Singapore. An island-wide survey. AB - OBJECTIVES: To determine the incidence of acute primary angle-closure glaucoma (APACG) in Singapore and to identify demographic and meteorological risk factors. DESIGN: A prospective, island-wide incidence study. SETTING: All government and private ophthalmological practices in Singapore, from March 1, 1995, to February 29, 1996. METHODS: New cases of APACG were identified by all ophthalmologists in Singapore during a 1-year period. Demographic and clinical details were recorded. RESULTS: One hundred eighty-nine people (208 eyes) were seen with APACG for the first time during the 1-year period. These new cases represent an incidence of 12.2 per 100,000 per year (95% confidence interval, 10.5-13.9) in those aged 30 years and older. Major risk factors identified were female sex (relative risk, 2.4), Chinese ethnic origin (relative risk, 2.8), and age of 60 years or older (relative risk, 9.1). Half of those affected were seen 3 days or more after the onset of symptoms. Attacks were more frequent on hotter days. There also was a relationship between the number of attacks per day and the mean number of sunspots and mean solar radio flux during the previous 30 days. CONCLUSIONS: There is a high incidence of APACG in Singapore, with elderly women being the highest risk group. Chinese Singaporeans are at higher risk than other ethnic groups (Malay and Indian). There is often a substantial delay before these patients consult a physician. The onset of APACG seems to be associated with meteorological factors. PMID- 9366675 TI - X-linked retinitis pigmentosa associated with a 2-base pair insertion in codon 99 of the RP3 gene RPGR. AB - BACKGROUND: Mutations in the RPGR gene at the RP3 locus have been found to cause x-linked retinitis pigmentosa in some families. OBJECTIVES: To identify a previously undescribed 2-base pair insertion in codon 99 of the RPGR gene and to describe the phenotype in a well-characterized family with X-linked retinitis pigmentosa. DESIGN: Case reports with clinical features, fluorescein angiography, kinetic perimetry, electrophysiological studies, and molecular genetics. SETTING: University medical centers. PATIENTS: Eight members of the family were screened for the codon 99 insertion in the RPGR gene. RESULTS: Three affected males were found to be hemizygous for the 2-base pair insertion; 2 carriers were heterozygous. This insertion creates a frameshift that would be expected to cause a premature arrest of translation after only 132 amino acids (683 amino acids less than the normal protein). The affected males had typical retinitis pigmentosa with visual field contraction and abnormal findings on electroretinograms with little to no rod activity, profoundly subnormal residual cone responses to single flash and 30-Hz flicker stimuli, and prolonged b-wave implicit times. The electroretinogram of a 49-year-old carrier showed amplitudes that were roughly half of normal. Carrier women did not show a tapetallike fundus reflex but showed asymmetrical patchy pigmentary disturbances consistent with lyonization. CONCLUSION: A frameshifting 2-base pair insertion at codon 99 of the RPGR gene produced typical retinitis pigmentosa and carrier findings (but no tapetallike reflex) in this family. PMID- 9366678 TI - Visual function and quality of life among patients with glaucoma. AB - This study determines the relation between visual field impairment, visual functioning, and global quality of life in patients with glaucoma. Binocular visual field impairment was calculated from simultaneous Esterman visual field testing using the Humphrey automated perimeter. Visual acuity impairment, defined with the American Medical Association's Guides to the Evaluation of Permanent Impairment; visual functioning, measured with the VF-14 and the field test version of the National Eye Institute-Visual Functioning Questionnaire; and global quality of life, assessed with the Medical Outcomes Study 36-Item Short Form Health Survey, were determined in 147 consecutive patients with glaucoma. None of the Medical Outcomes Study 36-Item Short Form Health Survey domains demonstrated more than a weak correlation with visual field impairment. The VF-14 scores were moderately correlated (r = -0.58). Of the National Eye Institute Visual Functioning Questionnaire scales, peripheral vision (r = -0.60), distance activities (r = -0.56), and vision-specific dependency (r = -0.56) were moderately correlated with visual field impairment; vision-specific social functioning, near activities, vision-specific role difficulties, general vision, vision-specific mental health, color vision, and driving were modestly correlated with visual field impairment (r value between -0.32 and -0.55); visual pain was weakly correlated with visual field impairment; and general health and vision specific expectations were not notably correlated with visual field impairment. Statistically adjusting for visual acuity weakened the correlations. The Medical Outcomes Study 36-Item Short Form Health Survey indicated that our patients with glaucoma were comparable with previously studied patients without severe systemic medical problems. However, the Medical Outcomes Study 36-Item Short Form Health Survey scores did not correlate with visual field impairment in our study. Based on the moderate correlation between binocular visual field impairment with the VF 14 and the National Eye Institute-Visual Functioning Questionnaire, these questionnaires may be useful among patients with glaucoma. PMID- 9366677 TI - Cataract extraction rates in Olmsted County, Minnesota, 1980 through 1994. AB - OBJECTIVE: To analyze population-based trends in cataract extraction. DESIGN: Rochester Epidemiology Project databases; which capture virtually all health care services provided to residents of Olmsted County, Minnesota, were used to perform retrospective cohort analyses of rates of primary cataract extractions performed between 1980 and 1994. PARTICIPANTS: The population of Olmsted County, Minnesota. MAIN OUTCOME MEASURES: Incidence rates adjusted to the age and sex distribution of the 1990 US white population were analyzed using Poisson regression. RESULTS: The 4257 procedures performed on 3176 patients of all ages represented overall annual age-adjusted rates of 404 procedures per 100,000 females and 320 per 100,000 males. Annual age- and sex-adjusted rates for both sexes combined rose from 133 procedures per 100,000 in 1980 to a peak of 507 per 100,000 in 1992. The rates fell to 470 per 100,000 in 1994. Manual review of a random sample of records estimated case overascertainment at 0.9%. CONCLUSIONS: With the exception of 1988 and 1989, rates of cataract surgery in this geographically circumscribed population increased every year between 1980 and 1992. Data from 1993-1994 indicate that rates may have plateaued and possibly declined slightly. If sustained, these patterns could have major implications for future utilization of ophthalmologic resources. PMID- 9366679 TI - 150 years since Babbage's ophthalmoscope. AB - The discovery of the ophthalmoscope in 1851 is rightly attributed to Hermann von Helmholtz. However, 4 years earlier, in 1847, Charles Babbage nearly invented the instrument that was to revolutionize ophthalmological examination so dramatically. PMID- 9366680 TI - Botulinum toxin management of essential infantile esotropia in children. PMID- 9366681 TI - Scanning slit confocal microscopy of fungal keratitis. AB - In vivo scanning slit confocal microscopy was performed in a patient with Fusarium solani keratitis. Morphologically distinctive abundant filamentous structures were observed intrastromally. Confocal microscopy of the culture plate growing F solani from the patient's corneal scraping revealed filaments morphologically similar to the filaments observed in vivo. After 1 week of medical therapy, subsequent confocal microscopy showed an increased load of filaments, supporting the decision to perform a penetrating keratoplasty. Confocal microscopy confirmed that all of the fungus was eradicated. This aided in the decision to administer corticosteroids and quickly discontinue antifungal agents. PMID- 9366682 TI - Non-Hodgkin lymphoma and Kaposi sarcoma in an eyelid of a patient with acquired immunodeficiency syndrome. Multiple viruses in pathogenesis. AB - A 36-year-old patient with acquired immunodeficiency syndrome sought care because of an upper eyelid lesion that dramatically increased in size. The histopathologic examination revealed a high-grade diffuse large cell non-Hodgkin lymphoma in continuity with a Kaposi sarcoma. In situ hybridization revealed Epstein-Barr virus in the large cell lymphoma and Kaposi sarcoma-associated herpesvirus in the Kaposi sarcoma lesion. This collision tumor is an unusual presentation of 2 malignant neoplasms in a patient with acquired immunodeficiency syndrome, with in situ hybridization evidence of Epstein-Barr virus and Kaposi sarcoma-associated herpesvirus in the lesion. PMID- 9366683 TI - A case of Erdheim-Chester disease with orbital involvement. AB - The Erdheim-Chester disease is a rare idiopathic, systemic, histiocytic disorder. To our knowledge, ocular involvement has been reported in only 16 cases. We describe a 55-year-old man who had symmetrical exophthalmos and several skin nodules on the arms and trunk. A magnetic resonance imaging scan confirmed the presence of bilateral, intraconal, retrobulbar tumors. An examination of the histopathologic features of orbital and skin biopsy specimens revealed xanthogranulomatous infiltrate with Touton giant cells. Further systemic investigations showed bone and retroperitoneal involvement. Three years later, multiple eyelid xanthelasmas developed in the patient. These findings are consistent with the diagnosis of the Erdheim-Chester disease. The patient's condition is stable under therapy with low-dose corticosteroids. His survival is longer than usually described in the literature. PMID- 9366684 TI - Fluctuating vision in Best disease. PMID- 9366685 TI - Acute histoplasmosis choroiditis in 2 immunocompetent brothers. PMID- 9366686 TI - Bilateral endophthalmitis as an initial presentation in meningococcal meningitis. PMID- 9366687 TI - Protracted postsurgical blindness with visual recovery following optic nerve sheath fenestration. PMID- 9366688 TI - Orbital cup. A device to facilitate ultrasound biomicroscopic examination of pars plana and peripheral retina. AB - Ultrasound biomicroscopy is a useful technique for anterior segment evaluation; however, examination of the pars plana and the peripheral retina is difficult. We describe a method that facilitates ultrasound biomicroscopic examination of these areas using using a modified swimming goggle(orbital cup) and an eyelid speculum. With this method, not only the pars plana but also structures up to 15 mm from the temporal limbus can be readily imaged. PMID- 9366689 TI - Unilateral pigment dispersion and glaucoma caused by angle recession. PMID- 9366690 TI - Iris ring melanoma masquerading as pigmentary glaucoma. PMID- 9366691 TI - Lacrimal gland choristoma of the ciliary body. PMID- 9366692 TI - Medical ethics and the excimer laser. PMID- 9366693 TI - 'Managed' care somewhat 'mangled'? PMID- 9366694 TI - Revolutionary inventions in the 20th century. The history of endoscopy. AB - Today, the wide variety of modern endoscopes allows routine diagnostic examinations. Precise observation is possible because of excellent optical and light transmission. Surgery can be performed while viewing a television screen, and video documentation and intraoperative photography are possible with outstanding quality. The invention of a rod-lens optical system by Harold H. Hopkins, PhD, in 1959 and the addition of fiberoptic light transmission by Karl Storz in 1960 marked a breakthrough in modern endoscopy. This article summarizes an interview with the instrument maker, Karl Storz. PMID- 9366695 TI - Triplane rhytidectomy. Combining the best of all worlds. AB - OBJECTIVE: To combine certain aspects of the sub-superficial musculoaponeurotic system (sub-SMAS) and subperiosteal rhytidectomies to maximize the advantages while minimizing the disadvantages of each. DESIGN: The subperiosteal rhytidectomy is used to reposition the ptotic malar fat pad concomitantly with the elevation of the corner of the mouth by means of shifting upward the origin of the zygomatic major muscle. The sub-SMAS rhytidectomy is used to maximize elevation of the jowl. SETTING: Ambulatory surgical facility. METHOD: Preauricular and temporal dissection is subcutaneous to the malar eminence above and angle of mandible below. A subperiosteal dissection of the middle part of the face is then accomplished through a sublabial approach combined with an incision over the malar eminence. An incision is made through the SMAS from the malar eminence to the mandibular angle and sub-SMAS dissection is accomplished under the jowl. The subperiosteal dissection is suspended to the temporal fascia and the SMAS dissection is imbricated with 2 suspension suture lines. CONCLUSIONS: Follow-up in patients who are 1-year postoperative demonstrates a continued youthful elevation and flattening of the melolabial fold and complete correction of the jowl. No facial nerve injury or hematomas were observed. PMID- 9366696 TI - The development of the Rhinosinusitis Disability Index. AB - Assessment of patient perception of disability and outcomes from treatment has become an integral part of medical care. General quality-of-life measurement tools have led to the development of disease-specific quality instruments. Conventional methods for evaluating nasal-sinus disease are inadequate to assess the impact of these disorders on everyday life. Therefore, using methods that are well established and validated for creating instruments, the Rhinosinusitis Disability. Index was created to evaluate the self-perceived impact of disease specific head and neck disorders. The development of the preliminary and final versions (30 items) of the Rhinosinusitis Disability Index is described. Content related validity using Cronbach's alpha measurement and construct-related validity were accomplished. A comparison of the responses between patients with and without documented nasal or sinus disease was used to verify that the Rhinosinusitis Disability Index is a valid measuring instrument for patients with sinus disease, and test-retest validity reveals reliability over time. PMID- 9366697 TI - A new classification and diagnostic criteria for invasive fungal sinusitis. AB - OBJECTIVE: To develop criteria for the diagnosis of invasive fungal sinusitis. DESIGN: Review of the literature on invasive fungal sinusitis in the context of a population of 30 patients with fungal sinusitis and 24 patients with chronic bacterial sinusitis. SETTING: Tertiary care medical center. RESULTS: Our review revealed no consensus in the literature on the classification of the syndromes of invasive fungal sinusitis and no criteria for their diagnosis. Moreover, the existing syndromes of invasive fungal sinusitis lacked specificity and one of the more commonly cited syndromes, primary aspergillosis of the paranasal sinuses, is a granulomatous disease that occurs rarely outside Africa. Two of our 30 patients with fungal sinusitis had a previously unrecognized form of invasive disease. Both were middle-aged adults with well-controlled type 2 diabetes mellitus, apical orbital syndrome, and a similar course: proptosis resulting from fungal expansion out of an ethmoid sinus, a protracted illness of 6 months or longer, visual changes, late neurological symptoms reflecting cavernous sinus invasion, and death. The syndrome in these 2 patients is distinct from the syndrome of fulminant invasive fungal sinusitis, (eg, mucormycosis) with nasal eschar, intracerebral fungal dissemination by vascular invasion, and death in days, and the granulomatous form. CONCLUSIONS: We conclude that there are 3 forms of invasive fungal sinusitis and propose that they be termed (1) granulomatous, (2) acute fulminant, and (3) chronic invasive. The latter category reflects the syndrome seen in our 2 patients. Furthermore, the following 2 diagnostic criteria for invasive fungal sinusitis are proposed: (1) sinusitis confirmed by radiological imaging and (2) histopathological evidence of hyphal forms within sinus mucosa, submucosa, blood vessels, or bone. The specificity of hyphae within sinus mucosa for tissue invasion was supported by the absence of stainable hyphae in the mucosa of patients with chronic bacterial sinusitis or in the mucosa of our described patients with allergic fungal sinusitis and mycetoma. PMID- 9366698 TI - Relationship between patient-based descriptions of sinusitis and paranasal sinus computed tomographic findings. AB - OBJECTIVE: To evaluate the relationship of paranasal sinus symptoms with coronal computed tomographic (CT) findings. DESIGN: Prospective comparison of patient based symptoms with imaging findings. SETTING: Primary care and referral center office and hospital practices. PATIENTS: Of 586 consecutive patients referred by otolaryngologists and primary care physicians for CT of the paranasal sinuses, 221 (151 women and 70 men; age range, 13-82 years; mean age, 44 years) participated by completing the Sino-Nasal Outcome Test-20 (SNOT-20) clinical questionnaire immediately before undergoing CT. MAIN OUTCOME MEASURES: Radiologists blinded to the patients' responses scored the degree of mucosal thickening at each of 12 sites on CT scans using a staged scale of severity (0-2 points). Bivariate analysis was performed to assess the relationship between patients' symptoms and CT findings. RESULTS: The SNOT-20 scores ranged from 0 (normal) to 78 (mean, 34). The most commonly reported symptom was fatigue. The CT scores ranged from 0 (normal) to 24 (mean, 4.07). Seventy-five patients (34%) had normal findings on the CT scan. The maxillary sinus was the most commonly involved site (96 patients, or 43%). The SNOT-20 and CT scores failed to significantly correlate (r = 0.11, P < or = .09). When the subset of patients with "positive" or "very positive" CT scans were considered, no significant correlation was observed (r = 0.12, P < or = .16). For the 132 patients reporting facial pain, the mean CT score was lower than for patients without facial pain (3.78 vs 4.78, P = .21). CONCLUSION: Patient-based reports of paranasal sinus symptoms failed to correlate with findings on CT scans; therefore, CT should be reserved for delineating the anatomy and pattern of inflammatory paranasal disease prior to surgical intervention. PMID- 9366699 TI - Ofloxacin otic solution for treatment of otitis externa in children and adults. AB - OBJECTIVE: To compare the safety and efficacy of ofloxacin otic solution with those of Cortisporin otic solutions (neomycin sulfate, polymyxin B sulfate, and hydrocortisone) in otitis externa in adults and children. DESIGN: Two randomized, evaluator-blind, multicenter trials, 1 each in children and adults. SETTING: Twenty-three primary care and referral ambulatory care sites per trial. PATIENTS: A total of 314 adults (12 years and older) and 287 children (younger than 12 years). Of the total, data for 247 adults and 227 children were considered clinically evaluable (CE), and those for 98 children and 98 adults were microbiologically evaluable (ME). INTERVENTIONS: Ofloxacin (adults, 0.5 mL; children, 0.25 mL) twice daily or Cortisporin (adults, 0.2 mL; children, 0.15 mL) 4 times daily for 10 days. MAIN OUTCOME MEASURES: The CE subjects were cured if all signs and symptoms resolved at posttherapy (days 11-13) and test-of-cure (days 17-20) visits. The ME subjects had microbiological and clinical successes if they were cured and had microbiological eradication or presumed eradication. RESULTS: Cure was observed in 82% and 97% of CE adults and children treated with ofloxacin and 84% and 95% of CE adults and children treated with Cortisporin, respectively. The most common pathogens at the pretherapy visit were Pseudomonas aeruginosa, Staphylococcus aureus, and enteric bacilli. There were no statistically significant differences in clinical or microbiological and clinical cure or in the rates of adverse events between treatment groups. CONCLUSIONS: Ofloxacin given twice daily is as safe and effective as Cortisporin given 4 times daily for otitis externa. The bacteriological findings and treatment responses do not differ between adults and children. PMID- 9366700 TI - Geographic variation in the utilization of esophagoscopy and bronchoscopy in head and neck cancer. AB - OBJECTIVE: To determine the extent to which esophagoscopy and bronchoscopy are being used in various regions of the United States in the initial examination of patients with head and neck cancer. DESIGN: Population-based study derived from Medicare claims data and information from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program. SETTING: Five SEER areas (San Francisco, Calif; Connecticut; Seattle, Wash; Iowa; and Detroit, Mich). PARTICIPANTS: The cohort included 1410 Medicare patients with squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx diagnosed between March 1, 1991, and December 31, 1993, in the 5 SEER areas. MAIN OUTCOME MEASURE: Rates of esophagoscopy and bronchoscopy according to SEER area. RESULTS: The proportion of patients who underwent esophagoscopy ranged from 12.9% (San Francisco) to 39.8% (Detroit) for patients with local cancer and from 22.2% (San Francisco) to 59.7% (Detroit) for patients with regional cancer. The proportion of patients who underwent bronchoscopy ranged from 6.9% (San Francisco) to 32.6% (Detroit) for patients with local cancer and from 12.8% (San Francisco) to 50.7% (Detroit) for patients with regional cancer. After controlling for differences in age, sex, race, tumor site, tumor grade, comorbidity, and socioeconomic status, SEER area remained independently associated with esophagoscopy and bronchoscopy (both P < .001). CONCLUSIONS: There is substantial geographic variation in the use of esophagoscopy and bronchoscopy as part of the initial examination of patients diagnosed as having head and neck cancer that cannot be explained by differences in patient or tumor characteristics. This variation likely underscores uncertainty and disagreement about the value of endoscopic screening for synchronous tumors. Additional research is required to determine whether routine endoscopic screening increases survival rates or improves quality of life. PMID- 9366701 TI - Reconstruction of the laryngopharynx after hemicricoid/hemithyroid cartilage resection. Preliminary functional results. AB - OBJECTIVE: To evaluate the use of a sensate radial forearm free flap and free cartilage graft for reconstruction of the laryngopharyngeal defect that results from resection of pyriform sinus carcinoma that extends to the apex of the pyriform sinus and includes the hemithyroid and hemicricoid cartilages. DESIGN: Case series review of 6 patients treated during a 2 1/2-year period with an average follow-up of 23 months. Factors evaluated included oncologic outcome, as well as functional outcome with regard to the onset and quality of the airway, speech, and deglutition. SETTING: Mount Sinai School of Medicine, New York, NY, an academic, tertiary referral center. PATIENTS: Six men ranging in age from 51 to 73 years underwent a partial laryngopharyngectomy that included the hemicricoid and hemithyroid cartilages as well as the ipsilateral thyroid lobe and either unilateral or bilateral lymph node dissections for squamous cell cancer that involved the apex of the pyriform sinus. INTERVENTION: These extensive laryngopharyngeal defects were reconstructed with a sensate radial forearm flap that resurfaced the endolarynx, restored the depth of the pyriform sinus, and reconstructed the remainder of the hypopharynx. In the final 4 patients, a free costal cartilage graft was used to restore the infrastructure of the larynx. OUTCOME MEASURES: The status of the margins, the incidence and site of recurrent cancer, the quality of speech, and the times to decannulation and removal of the gastrostomy tube. RESULTS: Three recurrences developed, with 1 each at the primary site, in the neck, and systemically. All but 1 patient who had completed radiotherapy by the last follow-up had been decannulated, and all but 1 patient regained the ability to maintain nutrition by mouth. Complications were limited to pharyngocutaneous fistulae requiring surgical closure in 3 patients early in the series. CONCLUSIONS: Functional reconstruction of extensive laryngopharyngeal defects can be achieved with a sensate radial forearm flap and a cartilage graft, with favorable functional results and acceptable morbidity, thus expanding the limits of conservation laryngopharyngeal surgery. PMID- 9366702 TI - Expression of p53 protein in advanced head and neck squamous cell carcinoma before and after chemotherapy. AB - BACKGROUND: The expression of p53 protein has been reported to be in the range of 35% to 67% in head and neck squamous cell carcinoma (HNSCC). Mutations of the gene for p53 protein have been associated with rapidly proliferating tumors, and p53 protein expression has been shown to be a significant predictor of worse survival in surgically resected HNSCC. To determine whether p53 protein expression in advanced (stages III and IV) HNSCC has any impact on tumor response to 2 to 3 courses of paclitaxel (Taxol) and carboplatin, we prospectively studied prechemotherapy specimens from patients with previously untreated, advanced-stage HNSCC. We also attempted to study residual tumors after chemotherapy to determine if the p53 status of the tumor changed. DESIGN: The expression of p53 protein was evaluated by immunohistochemical analysis (clone BP53-12-1; Bio-Genex, San Ramon, Calif). SETTING: Tertiary university medical center. INTERVENTION: Two to 3 courses of chemotherapy with paclitaxel and carboplatin. MAIN OUTCOME MEASURES: Pathologic complete remission or residual tumor. RESULTS: The results of p53 immunostaining were positive in 24 (67%) of 36 HNSCC specimens before chemotherapy. After chemotherapy, 8 patients achieved pathologic complete remission. Before chemotherapy, the tumor was p53 negative in 2 patients and positive in 6 patients. CONCLUSIONS: No correlation of p53 protein expression with response to chemotherapy was noted. The expression of p53 protein converted from positive to negative in 5 (42%) of 12 specimens from patients with residual tumor after chemotherapy, with no impact on clinical outcome. PMID- 9366703 TI - Human papillomavirus expression and p53 gene mutations in squamous cell carcinoma. AB - OBJECTIVES: To determine the incidence of human papillomavirus (HPV) infection and p53 gene mutation expression in squamous cell carcinomas (SCCs) of the oral cavity and tonsils, to correlate the presence of HPV and p53 gene mutation with known clinical and pathological features of SCC, and to determine whether infection with HPV or the presence of p53 gene mutations are independent prognosticators of patient survival. DESIGN: To accomplish this goal, 58 patients with SCCs of the oral cavity and 42 patients with SCCs of the tonsils were randomly examined. The cases examined met the criteria of 5-year clinical follow up, availability of complete staging information and treatment history, and the presence of paraffin-embedded tumor specimens. Immunohistochemical tests were performed to identify the mutant p53 protein. Human papillomavirus identification was accomplished with polymerase chain reaction, with confirmation via restriction fragment length polymorphisms. RESULTS: The incidence of p53 gene mutation expression for this series was 66%. Human papillomavirus infection was found in 11 patients (11%). There was a trend toward increased p53 gene mutation expression with advancing stage of tumor in the oral cavity cancer group, although this was less evident in the tonsil cancer population. The p53 gene mutation status was found not to correlate with the histological grade of the tumor, patient age or sex, recurrence rates, or survival status. Like p53 expression, there were no correlations found between the presence of HPV and age, sex, histological grade, or recurrence rates. However, a correlation did exist between HPV and survival status in the tonsil cancer group, with improved survival noted among patients with tonsil cancers infected with HPV compared with those not infected with HPV. A significant correlation existed with both p53 gene mutation status and HPV status with respect to alcohol and tobacco use. The presence of the p53 gene mutation positively correlated with increased tobacco and alcohol use, whereas infection with HPV predicted a significantly lower rate of alcohol and tobacco consumption. CONCLUSIONS: Human papillomavirus infection is an independent risk factor for the development of oral cavity and tonsil SCCs in those patients with a relatively low alcohol and tobacco use history. Conversely, there is a strong association between heavy alcohol and tobacco use and mutation of the p53 gene. Neither p53 gene mutation nor HPV infection serve as prognosticators of tumor behavior in SCCs of the oral cavity or tonsils, with the exception of improved survival noted among patients with tonsil cancers infected with HPV. PMID- 9366704 TI - Imaging quiz case 1. Bilateral agenesis of lateral semicircular canals with hypoplasia of the left internal auditory canal (IAC). PMID- 9366705 TI - Imaging quiz case 2. Complex temporal bone fracture. PMID- 9366706 TI - Exploring the past, charting the future. PMID- 9366707 TI - Glutathione depletion prevents lipopolysaccharide-induced local skin inflammation. AB - BACKGROUND: We have previously shown that the thiol-oxidizing agent diethyl maleate prevents lipopolysaccharide (LPS)-induced up-regulation of endothelial cell intercellular adhesion molecule-1 (ICAM-1) in vitro. OBJECTIVE: To determine the effect of glutathione depletion on the development of local skin inflammation in vivo, a model known to be dependent on ICAM-1. DESIGN: Swiss Webster mice were injected with intradermal LPS (30 micrograms) or isotonic saline solution. INTERVENTION: Mice were pretreated for 1 hour with intraperitoneal diethyl maleate (6 mmol/kg) or corn oil vehicle. MAIN OUTCOME MEASURES: Injection sites were harvested after 12 and 24 hours and evaluated for changes in vascular permeability and histological characteristics. To determine the mechanism underlying our findings, we evaluated skin ICAM-1 immunohistochemistry, levels of ICAM-1 protein and messenger RNA (mRNA), and neutrophil CD11b expression at the 24-hour point. RESULTS: Diethyl maleate significantly decreased the skin permeability index in a dose-dependent fashion at 24 hours but not at 12 hours. Skin histological examination under light microscopy showed a marked LPS-induced neutrophil infiltration at 24 hours, which was inhibited with diethyl maleate pretreatment. Immunohistochemical examination showed that diethyl maleate reduced ICAM-1 expression. In keeping with the hypothesized mechanism, diethyl maleate attenuated the LPS-induced up-regulation of ICAM-1 mRNA by 44%. Diethyl maleate also slightly but insignificantly reduced CD11b expression in vivo. CONCLUSIONS: Diethyl maleate markedly attenuates LPS-induced dermal inflammation, primarily through a reduction in ICAM-1 protein and mRNA expression. These data suggest that manipulation of the intracellular redox state may have a beneficial role in neutrophil-mediated inflammation. PMID- 9366708 TI - Growth hormone attenuates the acute-phase response to thermal injury. AB - OBJECTIVE: To determine the effects of growth hormone (GH) on the hepatic acute phase response (APR) in a burned rat model. SETTING: Laboratory. MATERIAL: Male Sprague-Dawley rats (weight, 300-350 g). INTERVENTIONS: Rats underwent a 40% total body surface area burn injury and received GH or saline solution daily by subcutaneous injection. Unburned rats served as controls. MAIN OUTCOME MEASURES: Hepatic messenger RNA (mRNA) expression and serum levels of alpha 1-acid glycoprotein and albumin were determined 2, 7, and 14 days after injury. RESULTS: The serum alpha 1-acid glycoprotein levels in GH-treated animals did not increase on days 2 and 7, whereas saline-treated animals showed a major increase. Hepatic mRNA expression increased dramatically on day 2 for burned groups; however, the mRNA pool levels of GH-treated animals showed a faster rate of decline to control levels on days 7 and 14. The albumin mRNA pool levels of GH-treated and control animals did not show significant differences, whereas the negative APR, indicated by loss of albumin mRNA, was more pronounced on day 7 in the saline-treated animals. By day 14, mRNA levels were comparable in all 3 groups. CONCLUSION: Growth hormone attenuated the positive APR, as indicated by a decrease in alpha 1 acid glycoprotein expression and production, and prevented the negative APR, as seen by an absence of a decline of albumin mRNA pool levels and serum concentration. We conclude that the beneficial effects of GH on thermal injury may be due in part to a modification of the APR. PMID- 9366709 TI - Nitric oxide down-regulates hepatocyte-inducible nitric oxide synthase gene expression. AB - BACKGROUND: The expression of inducible nitric oxide synthase (iNOS) contributes to the systemic manifestations of sepsis. OBJECTIVE: To determine whether nitric oxide (NO) can exert negative feedback regulation on iNOS gene expression. SETTING: Molecular biology research laboratory of the department of surgery. STUDY DESIGN: Isolated rat hepatocytes were cultured with a cytokine mix consisting of tumor necrosis factor alpha, interleukin 1 beta, and interferon gamma in the presence or absence of the NO donor S-nitroso-N-acetyl-D,L penicillamine. MAIN OUTCOME MEASURES: Nitrite and nitrate (NO2- and NO3-) levels were assayed. Hepatocyte iNOS messenger RNA and protein levels were assessed. Electromobility shift assays were performed for NF-kappa B DNA binding activity. Finally, iNOS enzyme activity was determined using high-performance liquid chromatography. RESULTS: Cytokine mix-induced hepatocyte iNOS mRNA and protein production and the addition of the NO donor S-nitroso-N-acetyl-D,L-penicillamine markedly attenuated iNOS mRNA and protein levels. Gel shift assays of the nuclear extracts disclosed that decreased cytokine mix-induced DNA binding activity for NF-kappa B in a concentration-dependent manner. Finally, NO failed to significantly inhibit iNOS enzyme activity. CONCLUSIONS: These data indicate that NO down-regulates iNOS gene transcription, and that the effect is mediated in part by inhibiting NF-kappa B activity. These results identify a novel negative feedback mechanism whereby NO down-regulates iNOS gene expression, possibly to limit overproduction during the septic response. PMID- 9366710 TI - The effect of empiric and prophylactic treatment with fluconazole on yeast isolates in a surgical trauma intensive care unit. AB - OBJECTIVE: To assess the effect of aggressive antifungal prophylaxis and empiric antifungal therapy using fluconazole on the mycotic microbiology and associated infectious complications in a surgical intensive care unit. DESIGN: Retrospective review of a cohort of critically ill surgical patients treated during an 11-month period. SETTING: Surgical intensive care unit, university hospital, state designated level I trauma center. PATIENTS: All patients treated with fluconazole during the study. MAIN OUTCOME MEASURES: Positive fungal cultures obtained after commencement of antifungal prophylaxis or antifungal treatment with fluconazole. Overall and infectious mortality rates for patients with positive cultures were also measured. RESULTS: Of 72 surgical patients who were treated with fluconazole; 16 (22%) had secondary mycoses. Fourteen (88%) of these patients were receiving fluconazole as antifungal prophylaxis or as empiric treatment of suspected but unproved infection. The predominant organisms isolated from these 16 patients were Candida glabrata (41%) and Candida parapsilosis (41%). Overall mortality for this group was 44%, and infectious mortality was 38%. The infectious mortality rate was significantly higher than the rate found in patients who were successfully treated with fluconazole for primary mycoses, and who did not have secondary infections with resistant organisms (mortality, 9%; P < .01, chi 2). CONCLUSIONS: Emergence of resistant species after treatment with fluconazole does occur in surgical patients, and suggests that the development of a secondary fungal infection with a resistant organism may be associated with a poor prognosis. PMID- 9366711 TI - Bacterial translocation is inhibited in inducible nitric oxide synthase knockout mice after endotoxin challenge but not in a model of bacterial overgrowth. AB - BACKGROUND: Studies have shown that nitric oxide (NO) and NO synthase (NOS) inhibitors injure and protect organs after endotoxin (lipopolysaccharide [LPS]) challenge. OBJECTIVE: To test the hypothesis that LPS-induced gut injury and bacterial translocation (BT) are mediated through activation of inducible NOS (iNOS). DESIGN: A randomized, controlled study using genetically altered, iNOS gene knockout mice. SETTING: University research laboratory. METHODS: Forty-five wild-type (iNOS+/+) or homozygous mutant (iNOS-/-) mice weighing 25 to 35 g were challenged with Escherichia coli LPS or saline (10 mg/ kg) intraperitoneally (n = 8/group). In a second set of experiments, a bacterial overgrowth model of BT (E coli monoassociation) was tested (n = 6-7/group). The mesenteric lymph nodes and cecums were cultured, and liver, ileal, and blood nitrite and nitrate levels measured 24 hours after LPS or E coli monoassociation. RESULTS: After LPS challenge, 87.5% of the iNOS+/+ mice but 0% of the iNOS-/- mice had BT to their mesenteric lymph nodes (P < .01; chi 2 analysis). Nitrite and nitrate levels of the liver, ileum, and blood were higher in the iNOS+/+ mice (P < .05). In the E coli overgrowth model, BT to mesenteric lymph nodes occurred in 100% of iNOS-/- and iNOS+/+ mice. CONCLUSIONS: In this limited study, LPS-induced BT did not occur in iNOS-deficient mice, suggesting that LPS induction of increased iNOS activity is necessary for LPS-induced BT to occur. In contrast, iNOS activation does not seem to be necessary in a bacterial overgrowth model of BT. PMID- 9366712 TI - Emerging evidence of selection of fluconazole-tolerant fungi in surgical intensive care units. AB - OBJECTIVE: To determine whether increased use of fluconazole has coincided with a shift in the relative proportion of fluconazole-tolerant species isolated from critically ill surgical patients in 2 university hospitals. DESIGN: Microbiological data and fluconazole administration frequencies were reviewed among patients treated in the surgical intensive care units (SICUs) from January 1, 1990, through December 31, 1995. SETTING: The SICUs of the University of Virginia Medical Center, Charlottesville, and the Hospital of the University of Pennsylvania, Philadelphia. MAIN OUTCOME MEASURES: The number and species types of all fungal isolates and the number of patients treated with fluconazole for each of the 6 years were determined. RESULTS: A sharp increase in the use of fluconazole among critically ill surgical patients has occurred at both medical centers from 1990-1995. The culture results of most patients treated with fluconazole were negative for fungi (73% and 63% at the University of Virginia Medical Center and the Hospital of the University of Pennsylvania, respectively); there was a greater tendency to use fluconazole at the University of Virginia Medical Center compared with the Hospital of the University of Pennsylvania (2.2% vs 1.8% of patients admitted to the SICU received it, respectively; P = .007). There was a significant increase in the proportion of Candida glabrata isolated at the University of Virginia Medical Center (P < .01) from 1990-1995, but a similar change was not detectable at the Hospital of the University of Pennsylvania. CONCLUSIONS: These data justify concern that the increased use of fluconazole in SICUs may be promoting a shift in the fungal flora that cause nosocomial infections toward species that are more difficult to treat. Prospective studies about the use of fluconazole for prophylaxis and empirical therapy among SICU patients are warranted before its widespread use in these settings continues. PMID- 9366713 TI - Twelfth rib resection. Preferred therapy for subphrenic abscess in selected surgical patients. AB - OBJECTIVE: To assess the role of 12th rib resection in the treatment of postoperative, subphrenic abscesses. DESIGN: Consecutive case series. SETTING: University hospital, level I trauma center. PATIENTS: Operative logs for a 13 year period were reviewed for all patients undergoing 12th rib resection for drainage of a postoperative subphrenic abscess. Each individual medical record was reviewed for demographic data, primary diagnosis, computed tomographic scan findings, and clinical status (temperature, white blood cell count, and Acute, Physiologic, Age, and Chronic Health Evaluation II score) at the time of rib resection. MAIN OUTCOME MEASURES: Operative results, microbiological data, complications, and outcomes. RESULTS: Twenty-six patients underwent 27 rib resections for a secondary left subphrenic (23) or a right subhepatic (4) abscess. All patients had undergone at least 1 prior laparotomy (average, 1.5; range, 1-4). Sixteen patients had traumatic injuries, and 7 had complicated pancreatitis. Twelve patients had undergone prior failed attempts at percutaneous drainage before rib resection. Fourteen patients underwent operative drainage without attempted percutaneous drainage, mainly for peripancreatic (7) or multiloculated (3) abscesses. There were 3 postoperative complications (3/27 [11%]): a gastrocutaneous fistula, a gastrocolic-cutaneous fistula requiring laparotomy and temporary colostomy, and fasciitis in the resection site. Four (15%) of the 26 patients died: 3 died of progressive multiple system organ failure, and 1 died of an unrelated injury. The remaining 20 (77%) of the patients were discharged from the hospital with healing wounds and no further episodes of intra-abdominal infection. CONCLUSIONS: Twelfth rib resection is an effective alternative therapy for secondary subphrenic abscesses. The nature of the incision allows for open, dependent drainage; avoids subsequent laparotomy; and effectively controls intra-abdominal infections. Twelfth rib resection remains a useful tool in the treatment of subphrenic abscess and may be the preferred approach when other attempts at abscess drainage have failed. PMID- 9366714 TI - Testosterone receptor blockade after hemorrhage in males. Restoration of the depressed immune functions and improved survival following subsequent sepsis. AB - BACKGROUND: Recent studies suggest that androgen depletion by castration before hemorrhage has protective effects on cell-mediated immunity in male mice after soft tissue trauma and hemorrhagic shock. OBJECTIVE: To determine whether treatment with an androgen receptor blocker (eg, flutamide) after trauma hemorrhage and sepsis has any salutary effects on cell-mediated immunity and on the survival of male animals under those conditions. DESIGN: Male C3H/HeN mice were either sham operated or subjected to hemorrhagic shock (mean [+/- SEM] blood pressure, 35 +/- 5 mm Hg for 90 minutes) followed by adequate fluid resuscitation (with shed blood and lactated Ringer solution). The animals then received either vehicle or 25-mg/kg body weight flutamide subcutaneously immediately after the resuscitation as well as 24 and 48 hours thereafter. At 48 hours after shock, sepsis was induced by cecal ligation and puncture. Sham-operated animals underwent laparotomy only. At 24 hours after cecal ligation and puncture, the animals were killed, blood was collected, and splenocytes and splenic macrophages were harvested to produce nonadherent and adherent cultures. Splenocytes were evaluated for splenocyte proliferation and interleukin 2 release, while interleukin 1 and interleukin 6 release were assayed in splenic macrophages. Plasma testosterone and corticosterone levels were also measured by radioimmunoassay. In a separate set of experiments, survival was measured over a period of 9 days after the induction of sepsis. RESULTS: Hemorrhage followed by sepsis produced a significant (P < .05) depression of splenocyte and macrophage functions in vehicle-treated animals. In contrast, animals treated with flutamide showed markedly improved immune functions, as evidenced by restoration of splenocyte proliferation, interleukin 2 release, splenic macrophage interleukin 1 release, and improvement of splenic macrophage interleukin 6 release. Plasma corticosterone levels were notably elevated while testosterone levels were depressed after hemorrhage and the induction of sepsis. The survival rate of the animals in the flutamide-treated group was also notably higher than the survival rate of animals in the vehicle-treated group subjected to hemorrhage and sepsis. CONCLUSION: The findings that flutamide not only markedly improves the depressed immune functions but also the survival of animals after hemorrhage and the induction of sepsis suggest that the short-term administration of androgen receptor blocker in males after trauma represents a safe and novel approach for preventing immune deficiency and decreasing the mortality rate from subsequent sepsis. PMID- 9366715 TI - Cytokine activation through sublethal hemorrhage is protective against early lethal endotoxic challenge. AB - OBJECTIVES: To determine the immunologic consequences of nonlethal hemorrhage on subsequent exposure to lipopolysaccharide (LPS) and to determine the role of interleukin 1 beta (IL-1) specifically in mediating the response to LPS with and without prior hemorrhage. DESIGN: Prospective, randomized, controlled experimental trial. PARTICIPANTS: Male BALB/c mice and transgenic mice deficient in IL-1 converting enzyme. INTERVENTIONS: Animals were subjected to hemorrhage (by cardiac puncture), LPS challenge by intraperitoneal injection, or hemorrhage followed 24 hours later by LPS challenge. Mortality was assessed every 4 hours for 96 hours following hemorrhage or LPS exposure. Serum IL-1 levels were determined 24 hours after exposure to hemorrhage and LPS. SETTING: University of South Florida Core General Surgery Research Facility, Tampa. MAIN OUTCOME MEASURES: Mortality and serum IL-1 levels. RESULTS: Hemorrhage alone resulted in complete survival, whereas LPS alone resulted in near-complete (95%) mortality. Hemorrhage, when given 24 hours before LPS challenge, afforded significant protection compared with LPS alone (67% survival vs 5% survival; P < .001). Serum IL-1 levels 24 hours after exposure to LPS were significantly lower in prehemorrhaged mice than in those receiving LPS alone. Transgenic mice incapable of producing biologically active IL-1 were further protected, demonstrating near complete (95%) survival following hemorrhage and LPS challenge. CONCLUSIONS: Cytokine activation through nonlethal hemorrhage attenuates subsequent IL-1 response to early immunologic challenge. Such immune suppression appears to be protective early on and is supported by the near-complete immunity to LPS in animals incapable of producing biologically active IL-1. PMID- 9366716 TI - Effect of route of delivery and formulation of postoperative nutritional support in patients undergoing major operations for malignant neoplasms. AB - OBJECTIVE: To study the effect of the route of delivery and formulation of postoperative nutritional support on host defense, protein metabolism, infectious complications, and outcome. DESIGN: Prospective, randomized, clinical trial. SETTING: Department of Surgery at a university hospital. PATIENTS: Two hundred sixty candidates for pancreaticoduodenectomy or gastrectomy for cancer. INTERVENTIONS: Patients were randomly allocated into 3 groups during surgery. Starting 6 hours after operation, the first group received a standard enteral formula (standard group; n = 87); the second, the same enteral formula enriched with arginine, omega-3 fatty acids, and RNA (immunonutrition group; n = 87); and the third, total parenteral nutrition (parenteral group; n = 86). The 3 regimens were isocaloric and isonitrogenous. The nutritional goal was 105 kJ/kg per day. MAIN OUTCOME MEASURES: Immune response by phagocytosis ability of polymorphonuclear cells, interleukin (IL)-2 receptor levels, and delayed hypersensitivity response; protein synthesis by IL-6 and prealbumin; tolerance of enteral feeding; incidence of postoperative complications; and length of hospital stay. RESULTS: The immunonutrition group had a significantly better recovery of the immune parameters on postoperative day 8 compared with the other groups. Linear regression analysis showed an inverse correlation between IL-6 and preambulin levels (r = 0.766) only in the immunonutrition group. Only 11 patients (6.3%) in both enteral groups did not reach the nutritional goal. Postoperative infection rate was 14.9% (13/87) in the immunonutrition group, 22.9% (20/87) in the standard group, and 27.9% (24/86) in the parenteral group (P = .06). Mean +/- SD length of hospital stay was 16.1 +/- 6.2, 19.2 +/- 7.9, and 21.6 +/- 8.9 days in the immunonutrition, standard, and parenteral groups, respectively (P = .01 vs standard group; P = .004 vs parenteral group). CONCLUSIONS: Early postoperative enteral feeding is a valid alternative to parenteral feeding in patients undergoing major surgery. Immunonutrition enhances the host response, induces a switch from acute-phase to constitutive proteins, and improves outcome. PMID- 9366717 TI - Pancreatic ascites as a powerful inducer of inflammatory cytokines. The role of known vs unknown factors. AB - OBJECTIVES: To determine if pancreatic ascites will induce interleukin 1 beta (IL 1 beta) or tumor necrosis factor alpha (TNF-alpha) production outside the pancreas and examine the possible components responsible. DESIGN: Severe pancreatitis was induced in rats (n = 30) by pancreatic duct infusion with 4% glycodeoxycholic acid; pancreatic ascites was collected 18 hours later. In vitro studies used quiescent murine splenic or pulmonary macrophages (10(5)/mL) which were exposed to media alone (control), trypsin, chymotrypsin, cathepsin-B, 20% ascites (vol/vol), 50% ascites, or endotoxin (lipopolysaccharide, 10 micrograms/mL, positive control) for 4 hours. Subsequently, pancreatic ascites was cultured for bacteria and assayed for endotoxin and cytokines (interleukin 1, interleukin 6, interleukin 8, TNF-alpha, or interferon gamma). The experiments were then repeated using 20% and 50% ascites that was sterile and cytokine-free (SCF ascites). In vivo studies used 100% (n = 8) or 50% (n = 12) SCF ascites or normal rat serum (control, n = 12) for a 10-second pulmonary lavage (100 microL) in adult mice, with lungs collected at 6 hours for cytokine gene analysis. SETTING: Surgical basic science research laboratory. MAIN OUTCOME MEASURES: Interleukin 1 beta and TNF-alpha gene induction was assessed by quantitative competitive reverse-transcription polymerase chain reaction and cytokine protein production was determined by enzyme-linked immunosorbent assay. RESULTS: Macrophages responded to untested and SCF ascites in a dose-dependent fashion, with a multifold increase in both IL-1 beta and TNF-alpha messenger RNA (mRNA) and protein, which was often more potent than lipopolysaccharide. Expression of IL-1 beta and TNF-alpha mRNA could not be induced by trypsin, chymotrypsin, or cathepsin-B. All animals undergoing lavage with 100% SCF ascites died within 2 hours, while those undergoing lavage with 50% SCF ascites showed a multifold increase in pulmonary IL-1 beta and TNF-alpha mRNA. CONCLUSIONS: Pancreatic ascites contains factors that are capable of inducing IL-1 beta and TNF-alpha production in vitro and in vivo. This effect cannot be reproduced by activated digestive enzymes and is propagated despite the absence of known inducers of cytokines such as bacteria, endotoxin, or other inflammatory cytokines. PMID- 9366718 TI - Invited commentary: spectrum of general surgery in rural America. PMID- 9366719 TI - 'A remarkable injury of the perinaeum, scrotum, and penis'. PMID- 9366720 TI - Review of prostaglandin use in labour induction. PMID- 9366721 TI - Clinical experience with a controlled-release, prostaglandin E2 intravaginal insert in the USA. PMID- 9366722 TI - A resource audit of labour induction at two hospitals in the UK. PMID- 9366723 TI - There is no such thing as aging. PMID- 9366724 TI - Will you still need me, will you still screen me, when I'm past 64? PMID- 9366725 TI - Including elderly people in clinical trials. PMID- 9366726 TI - The debate of the age. PMID- 9366727 TI - Randomised controlled trial to evaluate early discharge scheme for patients with stroke. AB - OBJECTIVE: To assess the clinical effectiveness of an early discharge policy for patients with stroke by using a community based rehabilitation team. DESIGN: Randomised controlled trial to compare conventional care with an early discharge policy. SETTING: Two teaching hospitals in inner London. SUBJECTS: 331 medically stable patients with stroke (mean age 71) who lived alone and were able to transfer independently or who lived with a resident carer and were able to transfer with help. INTERVENTIONS: 167 patients received specialist community rehabilitation for up to 3 months after randomisation. 164 patients continued with conventional hospital and community care. MAIN OUTCOME MEASURES: Barthel score at 12 months. Secondary outcomes measured impairment with motoricity index, minimental state examination, and Frenchay aphasia screening test; disability with the Rivermead activity of daily living scales, hospital anxiety and depression scale, and 5 m walk; handicap with the Nottingham health profile; carer stress with caregiver strain index and patient and carer satisfaction. The main process measure was length of stay after randomisation. RESULTS: One year after randomisation no significant differences in clinical outcomes were found apart from increased satisfaction with hospital care in the community therapy group. Length of stay after randomisation in the community therapy group was significantly reduced (12 v 18 days; P < 0.0001). Patients with impairments were more likely to receive treatment in the community therapy group. CONCLUSIONS: Early discharge with specialist community rehabilitation after stroke is feasible, as clinically effective as conventional care, and acceptable to patients. Considerable reductions in use of hospital beds are achievable. PMID- 9366728 TI - Association between features of the insulin resistance syndrome and Alzheimer's disease independently of apolipoprotein E4 phenotype: cross sectional population based study. AB - OBJECTIVE: To determine the association between features of the insulin resistance syndrome and Alzheimer's disease. DESIGN: Cross sectional population based study. SUBJECTS: 980 people aged 69 to 78 (349 men, 631 women). SETTING: Population of Kuopio, eastern Finland. MAIN OUTCOME MEASURES: Presence of features of the insulin resistance syndrome and diagnosis of Alzheimer's disease by detailed neurological and neuropsychological evaluation. RESULTS: 46 (4.7%) subjects were classified as having probable or possible Alzheimer's disease. In univariate analyses, apolipoprotein E4 phenotype (odds ratio; 95% confidence interval 3.24: 1.77 to 5.92), age (1.16; 1.05 to 1.29), low level of education (0.82; 0.72 to 0.93), low total cholesterol concentration (0.77; 0.59 to 1.00), high systolic blood pressure (1.01; 1.00 to 1.03), high fasting and 2 hour plasma glucose concentrations (1.11; 1.01 to 1.23 and 1.08; 1.03 to 1.13, respectively), high fasting and 2 hour insulin concentrations (1.05; 1.02 to 1.08 and 1.003; 1.00 to 1.01, respectively), and abnormal glucose tolerance (1.86; 1.23 to 2.80) were significantly associated with Alzheimer's disease. In multivariate analysis including apolipoprotein E4 phenotype, age, education, systolic blood pressure, total cholesterol concentration, fasting glucose concentration, and insulin concentration, apolipoprotein E4 phenotype, age, education, total cholesterol, and insulin were significantly associated with Alzheimer's disease. In 532 non diabetic subjects without the e4 allele hyperinsulinaemia was associated with an increased risk for Alzheimer's disease (prevalence of disease 7.5% v 1.4% in normoinsulinaemic subjects, P = 0.0004). In contrast, in the 228 with the e4 allele hyperinsulinaemia had no effect on the risk of disease (7.0% v 7.1%, respectively). CONCLUSION: Features of the insulin resistance syndrome are associated with Alzheimer's disease independently of apolipoprotein E4 phenotype. PMID- 9366729 TI - Development and evaluation of evidence based risk assessment tool (STRATIFY) to predict which elderly inpatients will fall: case-control and cohort studies. AB - OBJECTIVES: To identify clinical characteristics of elderly inpatients that predict their chance of falling (phase 1) and to use these characteristics to derive a risk assessment tool and to evaluate its power in predicting falls (phases 2 and 3). DESIGN: Phase 1: a prospective case-control study. Phases 2 and 3: prospective evaluations of the derived risk assessment tool in predicting falls in two cohorts. SETTING: Elderly care units of St Thomas's Hospital (phase 1 and 2) and Kent and Canterbury Hospital (phase 3). SUBJECTS: Elderly hospital inpatients (aged > or = 65 years): 116 cases and 116 controls in phase 1,217 patients in phase 2, and 331 in phase 3. MAIN OUTCOME MEASURES: 21 separate clinical characteristics were assessed in phase 1, including the abbreviated mental test score, modified Barthel index, a transfer and mobility score obtained by combining the transfer and mobility sections of the Barthel index, and several nursing judgements. RESULTS: In phase 1 five factors were independently associated with a higher risk of falls: fall as a presenting complaint (odds ratio 4.64 (95% confidence interval 2.59 to 8.33); a transfer and mobility score of 3 or 4 (2.10 (1.22 to 3.61)); and primary nurses' judgment that a patient was agitated (20.9 (9.62 to 45.62)), needed frequent toileting (2.48 (1.08 to 5.70)), and was visually impaired (3.56 (1.26 to 10.05)). A risk assessment score (range 0-5) was derived by scoring one point for each of these five factors. In phases 2 and 3 a risk assessment score > 2 was used to define high risk: the sensitivity and specificity of the score to predict falls during the following week was 93% and 88% respectively in phase 2 and 92% and 68% respectively in phase 3. CONCLUSION: This simple risk assessment tool predicted with clinically useful sensitivity and specificity a high percentage of falls among elderly hospital inpatients. PMID- 9366730 TI - Impact of mild cognitive impairment on survival in very elderly people: cohort study. PMID- 9366731 TI - Foot morbidity and exposure to chiropody: population based study. PMID- 9366732 TI - Mortality related to cold weather in elderly people in southeast England, 1979 94. PMID- 9366733 TI - Adverse drug reactions in elderly patients as contributing factor for hospital admission: cross sectional study. PMID- 9366734 TI - Breast examinations in older women: questionnaire survey of attitudes of patients and doctors. PMID- 9366735 TI - Exclusion of elderly people from clinical research: a descriptive study of published reports. PMID- 9366736 TI - Acute viral infections of upper respiratory tract in elderly people living in the community: comparative, prospective, population based study of disease burden. AB - OBJECTIVE: To evaluate the disease burden of upper respiratory infections in elderly people living at home. DESIGN: Prospective surveillance of elderly people. INTERVENTION: None. SETTING: Leicestershire, England SUBJECTS: 533 subjects 60 to 90 years of age. MAIN OUTCOME MEASURES: Pathogens, symptoms, restriction of activity, duration of illness, medical consultations, interval between onset of illness and medical consultation, antibiotic use, admission to hospital, and death. RESULTS: 231 pathogens were identified for 211 (43%) of 497 episodes for which diagnostic specimens were available: 121 (52%) were rhinoviruses, 59 (26%) were coronaviruses, 22 (9.5%) were influenza A or B, 17 (7%) were respiratory syncytial virus, 7 (3%) were parainfluenza viruses, and 3 (1%) were Chlamydia species; an adenovirus and Mycoplasma pneumoniae caused one infection each. Infections occurred at a rate of 1.2 episodes per person per annum (95% confidence interval 1.0 to 1.7; range 0-10) and were clinically indistinguishable. Lower respiratory tract symptoms complicated 65% of upper respiratory infections and increased the medical consultation rate 2.4-fold (chi 2 test P < 0.001). The median interval between onset of illness and medical consultation was 3 days for influenza and 5 days for other infections. Rhinoviruses caused the greatest disease burden overall followed by episodes of unknown aetiology, coronaviruses, influenza A and B, and respiratory syncytial virus. CONCLUSIONS: Respiratory viruses cause substantial morbidity in elderly people. Although respiratory syncytial virus and influenza cause considerable individual morbidity, the burden of disease from rhinovirus infections and infections of unknown aetiology seems greater overall. The interval between onset of illness and consultation together with diagnostic difficulties raises concern regarding the role of antiviral drugs in treating influenza. PMID- 9366737 TI - Randomised controlled trial of a general practice programme of home based exercise to prevent falls in elderly women. AB - OBJECTIVE: To assess the effectiveness of a home exercise programme of strength and balance retraining exercises in reducing falls and injuries in elderly women. DESIGN: Randomised controlled trial of an individually tailored programme of physical therapy in the home (exercise group, n = 116) compared with the usual care and an equal number of social visits (control group, n = 117). SETTING: 17 general practices in Dunedin, New Zealand. SUBJECTS: Women aged 80 years and older living in the community and registered with a general practice in Dunedin. MAIN OUTCOME MEASURES: Number of falls and injuries related to falls and time between falls during one year of follow up; changes in muscle strength and balance measures after six months. RESULTS: After one year there were 152 falls in the control group and 88 falls in the exercise group. The mean (SD) rate of falls was lower in the exercise than the control group (0.87 (1.29) v 1.34 (1.93) falls per year respectively; difference 0.47; 95% confidence interval 0.04 to 0.90). The relative hazard for the first four falls in the exercise group compared with the control group was 0.68 (0.52 to 0.90). The relative hazard for a first fall with injury in the exercise group compared with the control group was 0.61 (0.39 to 0.97). After six months, balance had improved in the exercise group (difference between groups in change in balance score 0.43 (0.21 to 0.65). CONCLUSIONS: An individual programme of strength and balance retraining exercises improved physical function and was effective in reducing falls and injuries in women 80 years and older. PMID- 9366738 TI - Effectiveness of influenza vaccination policy at targeting patients at high risk of complications during winter 1994-5: cross sectional survey. PMID- 9366739 TI - Recent advances. Geriatric medicine. PMID- 9366740 TI - Geriatric medicine: a brief history. PMID- 9366741 TI - Molecular biology's impact on our understanding of aging. PMID- 9366742 TI - Population aging and health. PMID- 9366743 TI - Coronary heart disease: an older woman's major health risk. PMID- 9366744 TI - Healthy aging. PMID- 9366745 TI - Optimising drug treatment for elderly people: the prescribing cascade. PMID- 9366746 TI - Both the disposition and the means of cure: "Severe SIRS," "sterile shock," and the ongoing challenge of description. PMID- 9366747 TI - Hemodynamic monitoring: does the end justify the means? PMID- 9366748 TI - Pushing the envelope on futility. PMID- 9366749 TI - Antihypertensive agents following cardiac surgery. PMID- 9366750 TI - Tumor necrosis factor in septic shock and multiple system trauma. PMID- 9366751 TI - Tissue factor and thrombin in posttraumatic systemic inflammatory response syndrome. PMID- 9366752 TI - Global cerebral ischemia in humans: how long is too long? PMID- 9366753 TI - Pulmonary dysfunction after surgery involving cardiopulmonary bypass: do we understand the mechanisms? PMID- 9366754 TI - Significance of hyperlactatemia without acidosis during hypermetabolic stress. PMID- 9366755 TI - Give a little, take a little: resident education in the evolving healthcare environment. PMID- 9366756 TI - Noninvasive cardiac output monitoring. PMID- 9366757 TI - Evidence based medicine: how to use articles about harm: where are the emperor's clothes? PMID- 9366758 TI - Brain death determination in adults: more than meets the eye. PMID- 9366759 TI - American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference definitions of the systemic inflammatory response syndrome and allied disorders in relation to critically injured patients. AB - OBJECTIVES: To determine the frequency of the proposed definitions for the systemic inflammatory response syndrome (SIRS), sepsis and septic shock, and to further define severe SIRS and sterile shock as determined at 24 hrs of admission to an intensive care unit (ICU) in critically ill trauma patients without head injury, and their relationships to mechanism of injury, Acute Physiology and Chronic Health Evaluation (APACHE) II score, risk of death, Injury Severity Score (ISS), number of organ failures, and mortality rate. DESIGN: Prospective, inception cohort analysis. SETTING: Sixteen-bed surgical ICU in a teaching hospital. PATIENTS: Four hundred fifty critically injured patients without associated head trauma. Penetrating trauma accounted for 70% (gunshot 202; stab 113) and nonpenetrating trauma for 30% (motor vehicle collision 103; blunt 32) of admissions. Three hundred ninety-four (88%) patients underwent surgical procedures. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Infective and noninfective insults were distinguished by the need for therapeutic or prophylactic antibiotics, respectively, based on an established antibiotic policy. Three hundred ninety-five (87.8%) patients fulfilled a definition of the SIRS criteria. The frequency of the definitive categories was SIRS 21.8%, sepsis 14.4%, severe SIRS 8.4%, severe sepsis 13.6%, sterile shock 9.3%, and septic shock 20.2%. Patients with penetrating trauma had a significantly higher frequency of sepsis, severe sepsis, and septic shock (p < .01). The APACHE II score, risk of death, and number of organ failures increased significantly in both infective and noninfective groups with increasing severity of the inflammatory response. Sterile shock was associated with a significantly higher APACHE II score (p < .02), risk of death (p < .01), and number of organ failures (p = .03) compared with septic shock. Only sterile shock was associated with a significantly higher ISS (p < .01). Organ system failure was significantly (p < .001) higher in nonsurvivors compared with survivors in all categories. The only significant (p < .001) difference in mortality rate was found between patients in shock and all other categories. CONCLUSIONS: The current definitions of SIRS, sepsis, and related disorders in critically injured patients without head trauma show a significant association with physiologic deterioration and increasing organ dysfunction. The only significant association with mortality, however, is the presence of shock. The definitions require refinement, with the possible inclusion of more objective gradations of organ system failure, if they are to be used for stratifying severity of illness in seriously injured patients. PMID- 9366760 TI - Lithium dilution cardiac output measurement: a comparison with thermodilution. AB - OBJECTIVE: To compare the results of cardiac output measurements obtained by lithium dilution and thermodilution. DESIGN: Case series, observational study. SETTING: High-dependency postoperative unit and intensive care unit of a teaching hospital. PATIENTS: Forty patients were studied. Thirty-four patients had undergoing heart surgery requiring cardiopulmonary bypass within the previous 2 days; the diagnoses in the other patients were myocardial infarct (n = 2), septicemia (n = 2), adult respiratory distress syndrome, and pericardectomy. INTERVENTIONS: Cardiac output was measured five times in each patient, using lithium dilution (single measurement) and bolus thermodilution (series of three to six measurements according to standard clinical practice, taking the average of the closest three). In a subgroup of 14 patients, cardiac output was also measured using "continuous thermodilution." MEASUREMENTS AND MAIN RESULTS: Comparing lithium dilution with bolus thermodilution, the mean of the differences (lithium dilution-thermodilution) was -0.25 +/- 0.46 [SD] L/min. Linear regression analysis gave y = 0.31 + 0.89x (r2 = .94) for lithium dilution vs. thermodilution. CONCLUSIONS: The overall agreement between the two methods was good. The variability of the thermodilution measurements was greater than that of the lithium dilution measurements. The lithium dilution method is at least as accurate as bolus thermodilution and, since pulmonary artery catheterization is not needed, it has the advantages of being safe and quick to perform. PMID- 9366761 TI - Prediction of poor outcome of intensive care unit patients admitted from the emergency department. AB - OBJECTIVE: To assess whether physicians can identify very low likelihood of survival and very low likelihood of favorable functional outcome in adult nontrauma patients before admission to the intensive care unit (ICU) from the emergency department (ED). DESIGN: Prospective survey. SETTING: University hospital ED and ICU. PARTICIPANTS AND PATIENTS: Critical care fellows and ED physicians and all adult nontrauma patients admitted to the ICU from the ED over 1 yr. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The survey compared predictions of poor outcome from three sources: critical care fellows, ED physicians, and the admission Mortality Probability Model (MPM0). All patients were followed until hospital death or hospital discharge. Six-month follow-up data were obtained for patients predicted to have a < 2% chance of surviving with favorable functional outcome. In the ED, critical care fellows and ED physicians predicted likelihood of patient survival and likelihood of favorable functional outcome. MPM0 estimates of mortality were determined. The sensitivities, specificities, and positive predictive values were calculated for the predictions of < 2% survival and the predictions of < 2% chance of favorable functional outcome made by each prediction group. Complete data were obtained on 236 (96%) of 243 eligible patients. With regard to hospital mortality rate, fellows' predictions had a sensitivity of 27%, a specificity of 99%, and a positive predictive value of 88%; ED physicians' predictions had a sensitivity of 24%, a specificity of 98%, and a positive predictive value of 81%; and MPM0 predictions had a sensitivity of 2%, a specificity of 100%, and a positive predictive value of 100%. With regard to mortality rate combined with poor functional outcome, fellows' predictions had a sensitivity of 35%, a specificity of 99%, and a positive predictive value of 96%; ED physicians' predictions had a sensitivity of 37%, a specificity of 99%, and a positive predictive value of 96%. CONCLUSIONS: If a cutoff point of < 2% predicted survival is used in the triage of patients away from the ICU, the MPM0 has too low a sensitivity to be used as an effective screen. The low sensitivities and relatively low positive predictive values with wide confidence intervals of physician predictions of < 2% survival also preclude their use in triage. The addition of functional outcome as an end point improves the sensitivity, specificity, and positive predictive value of subjective predictions, making triage of patients away from the ICU at the time of ED evaluation a realistic possibility. PMID- 9366762 TI - Effect of antihypertensive agents on the arterial partial pressure of oxygen and venous admixture after cardiac surgery. AB - OBJECTIVE: To determine whether stopping nitroglycerin and sodium nitroprusside (both vasodilators) infusions in hypertensive, postcardiac surgical patients requiring a high FIO2 improves PaO2 and venous admixture. DESIGN: Prospective, clinical trial. SETTING: Intensive care unit in a university-affiliated hospital. PATIENTS: Thirty postcardiac surgical patients who, because of high FIO2 requirements, did not meet the criteria for weaning from mechanical ventilation and who were receiving infusions of nitroglycerin and/or sodium nitroprusside to control blood pressure. INTERVENTIONS: PaO2, venous admixture, and oxygen transport data were determined at baseline using arterial and mixed venous blood gas samples and hemodynamic values from a pulmonary artery catheter. The nitroglycerin and sodium nitroprusside infusions were stopped, and intravenous boluses of labetalol were administered to maintain a target blood pressure. After the vasodilator infusions were stopped, the baseline measurements were repeated to redetermine PaO2, venous admixture, and oxygen transport values. MEASUREMENTS AND MAIN RESULTS: Results included a mean increase in PaO2 from 79.3 +/- 15 torr (10.5 +/- 2.0 kPa) to 118.3 +/- 38 torr (15.7 +/- 5.1 kPa) and a mean decrease in venous admixture from 26.4 +/- 5.8% to 17.6 +/- 5.6% when the vasodilators were stopped. All 30 patients had an increase in PaO2 and a decrease in venous admixture. Because of the improvement in oxygenation, 28 of the 30 patients met the criteria for weaning from mechanical ventilation once nitroglycerin and sodium nitroprusside were stopped or decreased. Labetalol was well tolerated in this group of patients who had preserved ventricular function. CONCLUSIONS: Substituting labetalol for nitroglycerin and sodium nitroprusside improves arterial oxygenation and venous admixture in hypertensive postcardiac surgical patients who require a high FIO2. This change in therapy may allow patients to be weaned from mechanical ventilation sooner. PMID- 9366763 TI - Patterns of cytokine evolution (tumor necrosis factor-alpha and interleukin-6) after septic shock, hemorrhagic shock, and severe trauma. AB - OBJECTIVE: To compare the patterns of evolution of two proinflammatory cytokines (tumor necrosis factor [TNF]-alpha and interleukin-6 [IL-6]) in two major clinical entities associated with systemic inflammatory response: septic shock and multiple trauma (with and without hemorrhagic shock). DESIGN: Prospective study of two cohorts of patients. SETTING: Critical care unit and Emergency Center of a university hospital. PATIENTS: Twenty-five nontrauma patients with septic shock and 60 multiple trauma patients (of whom eight patients were resuscitated from hemorrhagic shock). INTERVENTIONS: Serial blood samples were collected in each patient for determination of serum cytokine concentrations. Samples were obtained over 7 days in septic shock patients and 11 days in trauma patients. Standard resuscitation techniques were used in each patient. Clinical and laboratory data were prospectively collected. MEASUREMENTS AND MAIN RESULTS: High concentrations of circulating TNF-alpha and IL-6 were found in patients with septic shock. High IL-6 concentrations, but normal TNF-alpha concentrations were detected in trauma patients. At study entry, TNF-alpha concentrations were higher in nonsurvivor septic shock than in nonsurvivor trauma patients (42 +/- 7 vs 13 +/- 2 pg/mL; p < .001). During the whole study period, nonsurvivor septic shock patients maintained higher TNF-alpha concentrations than nonsurvivor trauma patients (p < .001). In survivors in both groups, normal values for TNF-alpha were detected during the whole study period. At study entry, IL-6 concentrations were significantly higher in nonsurvivor septic shock patients than in nonsurvivor trauma patients (15,627 +/- 4336 vs. 317 +/- 124 pg/mL; p < .0001). During the whole study period, much higher concentrations of IL-6 were detected in septic shock patients than in trauma patients (p < .0001). In survivors, at study entry, IL-6 concentrations were much higher in septic shock patients than in trauma patients (3947 +/- 1410 vs. 247 +/- 41 pg/mL; p < .001). Higher IL-6 concentrations were maintained throughout the study period in septic shock patients than in trauma patients (p < .001). In septic shock patients, changes in both TNF-alpha and IL-6 were correlated with outcome, higher values being found in patients likely to die. Neither TNF-alpha nor IL-6 values were of any significant value in predicting outcome of trauma patients. When septic shock patients were compared with traumatized patients resuscitated from hemorrhagic shock, the former had much higher concentrations of both TNF-alpha and IL-6 throughout the study period (p < .01 to p < .00001). Increased IL-6 values were an indicator of the development of a nosocomial infection in trauma patients. In five trauma patients who developed a nosocomial pneumonia during the study period, the IL-6 concentration was 433 +/- 385 pg/mL before the onset of pneumonia, then peaked at 3970 +/- 1478 pg/mL on day 7, and returned to baseline (219 +/- 58 pg/mL) on day 11. CONCLUSIONS: In septic shock patients, high amounts of circulating TNF-alpha and IL-6 are found and then correlate with fatal outcome. In trauma patients (even those patients resuscitated from hemorrhagic shock), much less increased concentrations of IL-6 are detected while normal TNF alpha circulating concentrations are measured. In these patients, cytokine concentrations do not correlate with outcome. This finding suggests a much higher degree of activation of the immunoinflammatory cascade in septic shock than in multiple trauma patients. Increased IL-6 values are an indicator of the development of a nosocomial infection in trauma patients. PMID- 9366764 TI - Participation of tissue factor and thrombin in posttraumatic systemic inflammatory syndrome. AB - OBJECTIVE: To determine the roles of tissue factor and thrombin on the systemic inflammatory response syndrome (SIRS) in posttrauma patients, as well as to investigate the relationship between SIRS and sepsis. DESIGN: Prospective, cohort study. SETTING: General intensive care unit of a tertiary care emergency department. PATIENTS: Forty trauma patients were classified into subgroups, according to the duration of SIRS: non-SIRS patients (n = 9); patients with SIRS for < 2 days (n = 15); and patients with SIRS for > 3 days (n = 16). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Tissue factor antigen concentration, prothrombin fragment F1+2, thrombin antithrombin complex, fibrinopeptide A, and cross-linked fibrin degradation products (D-dimer) were measured on the day of admission, and on days 1 through 4 after admission. Simultaneously, the number of SIRS criteria that the patients met and the disseminated intravascular coagulation score were determined. The results of these measurements, frequency of acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome, sepsis, and outcome were compared among the groups. The values of all five hemostatic molecular markers in the patients with SIRS for > 3 days were significantly more increased than those molecular marker values measured in the other groups on the day of admission. These values continued to be markedly high up to day 4 of admission. The occurrence rates of disseminated intravascular coagulation in these patient groups were significantly higher than those rates in the other two groups (p = .0001), and the disseminated intravascular coagulation scores did not improve during the study period. The occurrence rates of ARDS (p < .05) and multiple organ dysfunction syndrome (p < .01) were higher in patients with SIRS for > 3 days compared with those rates in the other groups, and the patients with SIRS for > 3 days had a poor outcome. No significant difference was noted in the frequency of sepsis among the groups. CONCLUSIONS: Sustained SIRS is the main determinant for ARDS, multiple organ dysfunction syndrome, and outcome in posttrauma patients. Disseminated intravascular coagulation associated with massive thrombin generation and its activation is involved in the pathogenesis of sustained SIRS. Sepsis has a small role in early posttrauma multiple organ dysfunction syndrome. PMID- 9366765 TI - Brief episodes of ventricular fibrillation do not influence postischemic cerebral perfusion assessed by positron emission tomography. AB - OBJECTIVES: To establish the defibrillation threshold in patients receiving an implantable cardioverter defibrillator, at least three episodes of ventricular fibrillation are induced and converted back to regular rhythm, using direct current countershocks. The aim of this study was to examine the influence of repeated short episodes of ventricular fibrillation on global and regional cerebral perfusion. DESIGN: A prospective, descriptive study. SETTING: A positron emission tomography laboratory at a university hospital. PATIENTS: Four patients, admitted for defibrillation threshold tests 2 yrs after the implantation of a cardioverter defibrillator, were included in the study. Global and regional cerebral blood flow was measured by cerebral positron emission tomography, using an 15O-labeled tracer under propofol-induced general anesthesia. Electroencephalograms (EEGs) were concomitantly recorded. INTERVENTIONS: Induction and conversion of ventricular fibrillation. MEASUREMENTS AND MAIN RESULTS: No effect on global cerebral perfusion was observed after induced ventricular fibrillation lasting 21 +/- 3 secs. The average global cerebral perfusion was 23 +/- 1 mL/100 g/min after induction of anesthesia and 31 +/- 8 mL/100 g/min and 24 +/- 2 mL/100 g/min immediately after the termination of the first and second ventricular fibrillation episodes, respectively. Ten minutes after the second and the third threshold tests, global cerebral perfusion was 21 +/- 1 mL/100 g/min and 21 +/- 2 mL/100 g/min, respectively. Regional cerebral perfusion and EEGs were not influenced. CONCLUSION: Short episodes of ventricular fibrillation did not induce any measurable effects on global and regional cerebral perfusion detectable by positron emission tomography 30 secs and 10 mins after restitution of sinus rhythm. PMID- 9366766 TI - Early onset of acute pulmonary dysfunction after cardiovascular surgery: risk factors and clinical outcome. AB - OBJECTIVE: To define the incidence, risk factors, and clinical outcome of early pulmonary dysfunction after cardiovascular surgery for adults. STUDY: Inception cohort. SETTING: Adult cardiovascular intensive care unit (ICU). PATIENTS: All adult admissions after cardiovascular surgery without preoperative pulmonary parenchyma or vascular disease over a period of 12 consecutive months. INTERVENTION: Collection of data on demographics, preoperative organ insufficiency, emergency surgery, type of surgical procedure, cardiopulmonary bypass time, transfusion of blood products, postoperative arterial blood gases, and systemic hemodynamics on admission to the cardiovascular ICU. MEASUREMENTS AND MAIN RESULTS: Early postoperative pulmonary dysfunction was defined by mechanical ventilation with a PaO2/FIO2 ratio of < or = 150 torr (< or = 20 kPa) and chest radiography on admission to the cardiovascular ICU. Secondary outcome included postoperative renal and neurologic dysfunction, nosocomial infections, length of mechanical ventilation, hospitalization, and death. A total of 3,122 patients were evaluated and 1,461 patients satisfied the entry criteria of the study. Early postoperative pulmonary dysfunction was present in 180 (12%) patients on admission to the cardiovascular ICU. Preoperative variables: age of > or = 75 yrs (odds ratio 1.69, 95% confidence interval [CI] 1.06 to 2.65), body mass index of > or = 30 kg/m2 (odds ratio 1.60, 95% CI 1.09 to 2.32), mean pulmonary arterial pressure of > or = 20 mm Hg (odds ratio 1.60, 95% CI 1.13 to 2.28), stroke volume index of < or = 30 mL/m2 (odds ratio 1.57, 95% CI 1.08 to 2.26), serum albumin (odds ratio 0.71, 95% CI 0.49 to 0.97), history of cerebral vascular disease (odds ratio 1.81; 95% CI 1.08 to 2.96); operative variables: emergency surgery (odds ratio 2.12, 95% CI 1.01 to 4.51), total cardiopulmonary bypass time of > or = 140 mins (odds ratio 1.54, 95% CI 1.0 to 2.34); and postoperative variables (on admission to cardiovascular ICU): hematocrit of > or = 30% (odds ratio 2.46, 95% CI 1.71 to 3.56), systemic mean arterial pressure of > or = 90 mm Hg (odds ratio 1.67, 95% CI 1.13 to 2.42), and cardiac index of > or = 3.0 L/min/m2 (odds ratio 2.09, 95% CI 1.44 to 3.01) were predictors of early postoperative pulmonary dysfunction. Pulmonary dysfunction was associated with a postoperative increase of serum creatinine (1.36 +/- 0.4 vs. 1.24 +/- 0.4 mg/dL, p < .02), neurologic complications (3% vs. 1.6%, p < .001), nosocomial infections (3% vs. 1.6%, p < .001), prolonged mechanical ventilation (2.2 +/- 5.9 vs. 1.7 +/ 5.6 days, p < .001), length of stay in the cardiovascular ICU (4.4 +/- 12.2 vs. 2.6 +/- 6.2 days, p < .001) and hospital (14.8 +/- 13.1 vs. 10.5 +/- 8.0 days, p < .001), and death (4.4% vs. 1.6%, p < .001). CONCLUSIONS: The incidence of early postoperative pulmonary dysfunction is uncommon; however, once developed, it is associated with increased morbidity and mortality after cardiovascular surgery. Advanced age, large body mass index, preoperative increased pulmonary arterial pressure, low stroke volume index, hypoalbuminemia, history of cerebral vascular disease, emergency surgery, and prolonged cardiopulmonary bypass time are risk factors for early onset of severe pulmonary dysfunction after surgery. Postoperative hematocrit and systemic hemodynamics suggest that early postoperative pulmonary dysfunction can be a component of a generalized inflammatory reaction to cardiovascular surgery. PMID- 9366767 TI - Effects of crystalloid solutions on circulating lactate concentrations: Part 1. Implications for the proper handling of blood specimens obtained from critically ill patients. AB - OBJECTIVES: a) To test the hypothesis that circulating lactate concentrations are the same in simultaneously collected arterial and central venous blood specimens; b) to test the hypothesis that even small amounts of crystalloid solutions, which are inadequately "cleared" from these indwelling arterial and venous catheters, can lead to clinically important and misleading changes in the measured lactate values. DESIGN: A prospective, multiexperiment study. SETTING: A critical care research laboratory and a 20-bed intensive care unit (ICU). PATIENTS: Three hundred fifty-five patients. INTERVENTIONS: Blood samples were collected. MEASUREMENTS AND MAIN RESULTS: Experiment 1: Simultaneously collected arterial and central venous blood specimens were obtained on 148 occasions from 48 medical ICU patients receiving no lactated Ringer's solution (RL). Arterial and central venous lactate values were nearly identical in these patients. The correlation between the arterial and central venous lactate concentrations was excellent (r2 = .85; p < .0001) and the agreement between the arterial and central venous lactate concentrations was also excellent (bias and precision = 0.04 mmol/L and +/- 0.38 mmol/L, respectively). Experiment 2: Arterial and mixed venous blood samples were obtained from 100 percutaneous transluminal coronary angioplasty (PTCA) and 75 cardiac surgical patients immediately before the performance of these cardiac procedures. We found the central venous lactate concentrations to be higher than arterial lactate values in the cardiac surgical group, and there was a very poor correlation (r2 = .07) between arterial and central venous lactate values in the cardiac surgical group. The correlation between central venous and arterial lactate concentrations in the PTCA patients was excellent (r2 = .84) and similar to the findings of experiment 1. Since the cardiac surgical patients received RL and the PTCA patients received no RL, we speculated that the intravenous infusion of RL in the cardiac surgical group accounted for these discordant findings. To test this speculation, we performed experiments 3 and 4. Experiment 3: In a large bench study, blood specimens were divided into multiple 1-mL aliquot portions, to which 0.01, 0.05, 0.10, 0.50, or 1.0 mL of various crystalloid solutions, containing or not containing RL, were added. In a volume dependent and linear manner, solutions containing RL increased the circulating lactate concentration from 10% to > 400% of the baseline lactate value. In a volume-dependent and linear fashion, the non-RL crystalloid solutions decreased the lactate concentration by 0 to 66% of the baseline nondiluted lactate concentration. Experiment 4: In 30 different cardiac surgical patients, we simultaneously obtained central venous and arterial blood specimens. Patients this time received no RL, and catheter lines were adequately cleared (removal > 5 mL) of crystalloid solutions. We found a correlation (r2 = .82; p < .0001) that was virtually identical to the findings of experiment 1 and to the findings in the PTCA group of experiment 2. CONCLUSIONS: a) Arterial and central venous lactate concentrations are similar in hemodynamically stable critically ill patients, b) Even small amounts of RL-containing solutions in catheters used for blood sampling may cause false increases in the circulating lactate concentration. c) Even small amounts of non-RL crystalloid solutions in catheters used for blood sampling may falsely decrease circulating lactate values. d) When blood specimens are drawn from indwelling catheters, all crystalloid solutions must be cleared from the line. PMID- 9366768 TI - Use of different anticoagulants in test tubes for analysis of blood lactate concentrations: Part 2. Implications for the proper handling of blood specimens obtained from critically ill patients. AB - OBJECTIVES: a) To test the hypothesis that the measurement of the circulating lactate concentration is influenced by the anticoagulant in the test tube that contains the blood sample; b) to test the hypothesis that the measurement of the circulating lactate concentration is influenced by the tissue used for analysis. DESIGN: A prospective, controlled study. SETTING: A critical care research laboratory, a 20-bed intensive care unit (ICU), and the general wards. SUBJECTS: Twenty-three ICU and ward patients with hyperlactatemia and 19 healthy volunteers. INTERVENTIONS: Blood samples were collected for determination of blood lactate concentration. MEASUREMENTS AND MAIN RESULTS: Venous blood samples (12 mL) were obtained from each of the 19 normal subjects and each 12-mL specimen was evenly divided into six aliquot portions (six test tubes). Experiment 1: Of the six tubes, two tubes were set aside for experiment 2. The other four tubes were used to test four anticoagulants (one anticoagulant per tube). The anticoagulants tested were: sodium heparin; EDTA; lithium heparin; and sodium citrate. Lactate concentrations were analyzed using an ion-selective, amperometric electrode that we have previously validated. There were no statistically significant differences between the lactate concentrations derived from blood samples stored in sodium heparin, EDTA, or lithium heparin (p > .05; n = 19; Student-Newman-Keuls' multiple comparisons test). The lactate concentration of blood stored in sodium citrate, however, was lower than all other anticoagulants (p < .001; n = 19; Student-Newman-Keuls' multiple comparisons). Experiment 2: Of the remaining two test tube samples from each subject, one tube contained sodium heparin and the other tube did not contain an anticoagulant. Each of these two tubes was centrifuged at 50 degrees F (10 degrees C) for 15 mins to obtain plasma and serum samples. Lactate concentrations were measured in the serum and plasma and compared with those concentrations found in whole blood samples from the tube containing sodium heparin from experiment 1. The plasma and serum lactate concentrations were consistently higher than the whole blood lactate values from the same specimen (p < .05; n = 42; Student-Newman-Keuls' multiple comparisons test). Since experiment 1 involved the collection of blood from healthy volunteers with normal lactate concentrations, we chose to investigate whether this discordance between plasma or serum and whole blood was dependent on the lactate concentration. To answer this question, we studied 23 patients with known hyperlactatemia and found that in subjects with a lactate concentration of < 2.2 mmol/L, there was a difference of 0.11 mmol/L in the mean values between plasma and whole blood concentrations (p < .0004; n = 19; paired t test). In subjects with a lactate concentration of > 2.2 mmol/L, there was a difference of 0.14 mmol/L (p < .0001; n = 23; paired t-test) in the mean values between plasma and whole blood. In all samples at all concentrations, there was no significant difference between serum vs. plasma samples (p > .05; Student Newman-Keuls' test). CONCLUSIONS: a) Sodium citrate, as an anticoagulant, caused lower lactate concentrations to be measured as compared with heparin or EDTA; b) the measurement of lactate concentrations in plasma or serum samples yields a higher value than the concentration found in the original whole blood specimen. PMID- 9366769 TI - Effect of intravenous lactated Ringer's solution infusion on the circulating lactate concentration: Part 3. Results of a prospective, randomized, double blind, placebo-controlled trial. AB - OBJECTIVES: We previously discovered that small amounts of lactated Ringer's solution, which are inadequately cleared from an intravenous catheter, falsely increase the circulating lactate concentration in blood samples collected from that catheter. That finding prompted us to test the hypothesis that intravenous lactated Ringer's solution, infused at a rate used in resuscitation, would increase the circulating lactate concentration. DESIGN: A prospective, randomized, double-blinded, placebo-controlled study. SETTING: A critical care research laboratory. SUBJECTS: Twenty-four normal, healthy, adult volunteer subjects. INTERVENTIONS: Two intravenous catheters were placed. One was used for the infusion of the test solution and the other catheter was used for blood sampling. Blood samples were serially collected for the determination of blood lactate concentrations. MEASUREMENTS AND MAIN RESULTS: Twenty-four healthy adult volunteers were randomized to receive a 1-hr infusion of either lactated Ringer's solution (n = 6), 0.9% saline (n = 6), 5% dextrose in lactated Ringer's solution (D5RL) (n = 6), or 5% dextrose in water (D5W) (n = 6). Each subject received nothing by mouth after midnight. At 0800 hrs, catheters were inserted and each subject received 1 L of the assigned solution over 1 hr. Throughout the study, the subjects were at rest. Three-milliliter samples of venous blood were collected before, during (at 15, 30, 45, and 60 mins), and after (at 90, 120, and 240 mins) the infusion. Blood samples were placed on ice immediately after collection and analyzed within 5 mins of collection. Lactate concentrations were determined using an ion-selective, amperometric electrode, which we have previously validated. Lactate concentrations were compared between subjects receiving lactated Ringer's solution vs. subjects receiving normal saline. A similar comparison was made between subjects receiving D5RL vs. D5W at similar time points during the study. There were no clinically or statistically significant differences in lactate values at the time points studied in those subjects receiving lactated Ringer's solution vs. those persons receiving normal saline (p > .05; n = 12; Student-Newman-Keuls' multiple comparison test) or those subjects receiving D5W vs. those subjects infused with D5RL (p > .05; n = 12; Student-Newman-Keuls' multiple comparison test). In no case did the circulating lactate values exceed 2 mmol/L (the upper limit of normal). CONCLUSIONS: The short-term infusion of lactated Ringer's solution in normal adults (hemodynamically stable) does not falsely increase circulating lactate concentrations when 1 L is given over 1 hr. Therefore, clinicians should not disregard increased lactate concentrations in patients receiving a rapid infusion of lactated Ringer's solution. PMID- 9366770 TI - Increased intracellular cyclic adenosine 3', 5'-monophosphate inhibits release of tumor necrosis factor-alpha from human vascular tissue and cultured smooth muscle cells. AB - OBJECTIVES: We recently reported that bacterial lipopolysaccharide stimulates release of tumor necrosis factor (TNF)-alpha from both human vascular tissue and cultured smooth muscle cells. In the current study, we tested the hypothesis that increased intracellular cyclic adenosine 3',5'-monophosphate (cAMP) could inhibit TNF-alpha release. DESIGN: Prospective, repeated-measures analysis. SETTING: Academic research laboratory. SUBJECTS: Segments of internal mammary artery and saphenous vein from patients undergoing coronary artery bypass surgery. MEASUREMENTS AND MAIN RESULTS: Segments of saphenous vein and internal mammary artery and confluent smooth muscle cells cultured from these vessels were incubated in the presence of 20 micrograms/mL bacterial lipopolysaccharide, alone or with the addition of forskolin or 8-Br-cAMP. At 0, 1, 3, 6, 18, and 24 hrs, the incubation medium was removed from vessel segments or cells and was analyzed for biologically active TNF-alpha, using the L929 cell cytotoxicity assay. cAMP was extracted from tissue and cells with 0.1 N HCl and was analyzed by radioimmunoassay. Bacterial lipopolysaccharide stimulated the release of TNF alpha from internal mammary smooth muscle cells at all time points. For example, at 6 hrs, TNF-alpha concentration in the medium from lipopolysaccharide stimulated cells was 20 +/- 1.6 U/mg of cell protein, compared with 0.9 +/- 0.5 U/mg of cell protein in control cell medium (p < .05). Forskolin-inhibited bacterial lipopolysaccharide stimulated TNF-alpha release. In the presence of lipopolysaccharide and forskolin, TNF-alpha release at 6 hrs was 8.6 +/- 1.5 U/mg of cell protein (p < .05 vs. in the presence of bacterial lipopolysaccharide alone). Bacterial lipopolysaccharide, alone, had no effect on intracellular cAMP. Forskolin increased intracellular cAMP levels to 74.0 +/- 12 pmol/mg of cell protein at 6 hrs from a control level of 7.7 +/- 0.4 pmol/mg (p < .05). The 8-Br cAMP, an agent that mimics the action of intracellular cAMP, also inhibited TNF alpha release stimulated by lipopolysaccharide. Similar inhibition by forskolin and 8-Br-cAMP on TNF-alpha release was obtained with smooth muscle cells from saphenous vein. Finally, in tissue segments from either internal mammary artery or saphenous vein, both forskolin and 8-Br-cAMP inhibited lipopolysaccharide stimulated TNF-alpha release. CONCLUSIONS: These results are consistent with the conclusion that vascular tissue, particularly the smooth muscle cell, is a source of TNF-alpha. Further, bacterial lipopolysaccharide-stimulated tumor TNF-alpha release can be inhibited by increased intracellular cAMP. PMID- 9366771 TI - Survival in patients with nosocomial pneumonia: impact of the severity of illness and the etiologic agent. AB - OBJECTIVE: To assess the impact of severity of illness at different times, using the Mortality Probability Models (MPM II), and the impact of etiologic agent on survival in patients with nosocomial pneumonia. DESIGN: Retrospective, observational study. SETTING: Fourteen-bed medical-surgical intensive care unit (ICU) in a teaching hospital. PATIENTS: Sixty-two patients with nosocomial pneumonia who were receiving early appropriate antibiotic treatment. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Severity of illness at the time of admission to the ICU (M0), 24 hrs after admission (M24), and at the time of pneumonia diagnosis (M1) was determined using MPM II. Bacteriology was established by quantitative cultures from bronchoscopic samples. The outcome measure was the crude mortality rate. The crude mortality rate in the ICU was 59.7%, compared with average predicted mortality rates of 43.5% (M0), 36.4% (M24), and 52.2% (M1). We observed significant differences in mean MPM II determinations between survivors and nonsurvivors at M1 (39.3% vs. 60.9%, p = .001) but not at M0 and M24. In the univariate analysis, the variables most predictive of mortality were the presence of coma (p = .02), inotropic medication use (p = .001), and an MPM II determination of > 50% (p = .001) when pneumonia was diagnosed (M1). Multivariate analysis showed that, in the absence of Pseudomonas aeruginosa, an MPM II determination of > 50% at M1 was associated with a relative risk of death of 4.8. The presence of P. aeruginosa was associated with an increase in the risk of death of 2.6 and 6.36 in both populations with MPM II determinations at M1 of < or = 50% and > 50%, respectively. CONCLUSIONS: Severity of illness when pneumonia is diagnosed is the most important predictor of survival, and this determination should be used for therapeutic and prognostic stratification. In addition, the presence of P. aeruginosa contributed to an excess of mortality that could not be measured by MPM II alone, suggesting the importance of the pathogen in prognosis. PMID- 9366772 TI - Improved oxygenation by nitric oxide is enhanced by prior lung reaeration with surfactant, rather than positive end-expiratory pressure, in lung-lavaged rabbits. AB - OBJECTIVES: The inhalation of nitric oxide increases oxygenation by improving the ventilation/perfusion ratios in neonates with respiratory distress syndrome and those ratios in adults with acute respiratory distress syndrome. There is evidence that inhaled nitric oxide is ineffective when the lung remains atelectatic and poorly inflated. This study aimed to enhance nitric oxide delivery by improving lung aeration by means of exogenous surfactant or by increasing positive end-expiratory pressure. DESIGN: Experimental, comparative study. SETTING: Research laboratory of a large university. SUBJECTS: Twenty-eight adult New Zealand white rabbits, weighing 2.7 +/- 0.3 kg. INTERVENTIONS: Lung injury was induced by repeated whole-lung lavage with saline. The animals were mechanically ventilated with a tidal volume of 10 mL/kg, an FIO2 of 1.0, and a positive end-expiratory pressure of 6 cm H2O. Forty-five minutes after the last lavage, the animals were randomly assigned to five groups. In two groups, lung aeration was first increased either by instillation of a low dose of exogenous surfactant (25 mg/kg) or by increasing the positive end-expiratory pressure to 10 cm H2O, before inhalation of nitric oxide was started. In each of these animals, five different nitric oxide concentrations (4 to 20 parts per million) were inhaled for 30 mins, followed by a 30-min washout period. The other three groups served as controls and received only one treatment protocol: nitric oxide (4 to 20 parts per million), or surfactant (25 mg/kg), or positive end-expiratory pressure (10 cm H2O). MEASUREMENTS AND MAIN RESULTS: Before and after lavage, blood gases and lung mechanics were measured every 30 mins. Both strategies to increase lung aeration improved PaO2 values from 61 +/- 13 torr (8.1 +/- 1.7 kPa) to 200 to 300 torr (26.6 to 39.9 kPa) in 30 mins. After inhalation of nitric oxide, additional increases of oxygenation were seen only in the animals that received a low dose (25 mg/kg) of surfactant. The control group that inhaled nitric oxide showed no significant change in oxygenation, and four of the six animals did not survive the observation period. In the two groups in which positive end-expiratory pressure was increased to 10 cm H2O, half of the animals developed a pneumothorax during the observation period. CONCLUSION: These data indicate that inhaled nitric oxide is able to improve arterial oxygenation after alveolar recruitment by means of a low dose of exogenous surfactant, and not by increase of positive end-expiratory pressure from 6 to 10 cm H2O, in lung-lavaged rabbits. PMID- 9366773 TI - Cardiovascular toxicity of human cross-linked hemoglobin in a rabbit endotoxemia model. AB - OBJECTIVE: To determine the possible adverse effects of human cross-linked hemoglobin in endotoxemia. DESIGN: Prospective, controlled, laboratory trial. SETTING: Animal research laboratory. SUBJECTS: New Zealand white rabbits. INTERVENTIONS: Conscious rabbits received intravenous infusions of either lipopolysaccharide (LPS) alone (10 micrograms/kg, Escherichia coli 0111:B4), human hemoglobin cross-linked between the alpha chains (alpha alpha Hb, 0.7 g/kg), or both LPS and alpha alpha Hb. The cardiovascular effects of alpha alpha Hb and LPS as single agents or administered together were then studied in anesthetized rabbits. MEASUREMENTS AND MAIN RESULTS: Mortality in conscious animals that received alpha alpha Hb followed by LPS 4 hrs later (n = 5), or LPS and alpha alpha Hb at the same time (n = 6) was 60% and 67%, respectively. In anesthetized animals, infusion of both LPS and alpha alpha Hb (n = 6) resulted in hypoxia, lactic acidosis, ventricular arrhythmias, and decreased myocardial contractility and left ventricular pressure. In contrast, anesthetized rabbits that received alpha alpha Hb (n = 5) or LPS (n = 5) alone did not develop hypoxia, acidosis, alteration in myocardial contractility, or arrhythmias. Furthermore, death did not occur in any of the conscious animals that received either LPS (n = 7) or alpha alpha Hb (n = 4) as single agents. CONCLUSIONS: In an animal model of nonlethal endotoxemia, infusion of alpha alpha Hb significantly increases mortality. Our data suggest that mortality may be due to the acute increased cardiopulmonary toxicity of alpha alpha Hb in animals with underlying endotoxemia. PMID- 9366774 TI - Effects of inhaled nitric oxide and extracorporeal membrane oxygenation on pulmonary hemodynamics and lymph flow in oleic acid lung injury in sheep. AB - OBJECTIVE: To compare the effects of inhaled nitric oxide (NO) and extracorporeal membrane oxygenation (ECMO) on oxygenation, hemodynamics, and lymphatic drainage in an oleic acid lung injury model in sheep. DESIGN: Prospective, randomized study. SETTING: Animal research laboratory. ANIMALS: Thirty female sheep, weighing 35 to 40 kg. INTERVENTIONS: Acute lung injury was induced by central venous injection of oleic acid (0.5 mL/kg body weight). A chronic lymph fistula had been prepared through a right thoracotomy 3 days before the experiment. Animals were assigned randomly to the NO group (n = 14) or the ECMO group (n = 16). When a lung injury score of > 2.5 was achieved, the animals were given NO in dosage increments of 2, 5, 10, 20, and 40 parts per million (ppm), or placed on ECMO with an FIO2 of 0.21 (ECMO-21) and then 1.0 (ECMO-100) at the oxygenator. Mechanical ventilator parameters were kept constant to isolate the effects of NO and ECMO on systemic and pulmonary hemodynamics, cardiac output, oxygenation parameters, lymph/plasma protein ratio, and lymph flow. Measurements and calculations were performed after 1 hr at each individual step of NO concentration or FIO2. MEASUREMENTS AND MAIN RESULTS: In the ECMO group, PVRI and MPAP did not change and were significantly different from the NO group. In the NO group, there was a dose-dependent decrease in venous admixture, maximal at 10 ppm NO and decreasing from 40 +/- 6% to 23 +/- 10% (p < .05). This decrease was significantly different from the ECMO group, where there was no change. There was a significant increase in PaO2/FIO2 in the NO group, maximal at 10 ppm NO (84 +/- 11 to 210 +/- 90, p < .05), but a greater increase in PaO2/FIO2 on ECMO-21 (81 +/ 14 to 265 +/- 63) and a further increase on ECMO-100 (398 +/- 100) (p < .05). The lymph/plasma protein ratio remained unchanged in both groups after induction of lung injury by oleic acid. However, lymph flow decreased by 11 +/- 6% in the NO group, whereas it increased by 14 +/- 17% in the ECMO group (p < .05). CONCLUSIONS: In an oleic acid-induced sheep model of acute lung injury, there were significant differences between the effects of NO and ECMO on acute pulmonary hypertension, hypoxemia, hypercarbia, and lymph flow. NO significantly decreases pulmonary hypertension, whereas pulmonary hemodynamics were not substantially affected by ECMO. Both interventions reversed hypoxemia, but ECMO did so to a greater degree, and only ECMO improved hypercarbia. Only NO decreased lymph flow, possibly as an effect of decreased microvascular filtration pressure. This study did not attempt to evaluate the impact of these interventions on ventilatory requirements, barotrauma, or outcome. However, this model suggests that NO therapy may moderate pulmonary hypertension and improve lymph flow in acute lung injury. Clinical studies are needed to assess whether NO therapy might be beneficial in treatment of severe acute lung injury in older children and adults. PMID- 9366775 TI - Prolonged partial liquid ventilation using conventional and high-frequency ventilatory techniques: gas exchange and lung pathology in an animal model of respiratory distress syndrome. AB - OBJECTIVE: To evaluate the effect of prolonged partial liquid ventilation with perflubron (partial liquid ventilation), using conventional and high-frequency ventilatory techniques, on gas exchange, hemodynamics, and lung pathology in an animal model of lung injury. DESIGN: Prospective, randomized, controlled study. SETTING: Animal laboratory of the Infant Pulmonary Research Center, Children's Health Care-St. Paul. SUBJECTS: Thirty-six newborn piglets. INTERVENTIONS: We studied newborn piglets with lung injury induced by saline lavage. Animals were randomized into one of five treatment groups: a) conventional gas ventilation (n = 8); b) partial liquid ventilation with conventional ventilation (n = 7); c) partial liquid ventilation with high-frequency jet ventilation (n = 7); d) partial liquid ventilation with high-frequency oscillation (n = 7); and e) partial liquid ventilation with high-frequency flow interruption (n = 7). After induction of lung injury, all partial liquid ventilation animals received intratracheal perflubron to approximate functional residual capacity. After 30 mins of stabilization, animals randomized to high-frequency ventilation were changed to their respective high-frequency modes. Hemodynamics and blood gases were measured before and after lung injury, after perflubron administration, and then every 4 hrs for 20 hrs. Histopathologic evaluation was carried out using semiquantitative scoring and computer-assisted morphometric analysis on pulmonary tissue from animals surviving at least 16 hrs. MEASUREMENTS AND MAIN RESULTS: All animals developed acidosis and hypoxemia after lung injury. Oxygenation significantly (p < .001) improved after perflubron administration in all partial liquid ventilation groups. After 4 hrs, oxygenation was similar in all ventilator groups. The partial liquid ventilation-jet ventilation group had the highest pH; intergroup differences were seen at 16 and 20 hrs (p < .05). The partial liquid ventilation-oscillation group required higher mean airway pressure; intergroup differences were significant at 4 and 8 hrs (p < .05). Aortic pressures, central venous pressures, and heart rates were not different at any time point. Survival rate was significantly lower in the partial liquid ventilation-flow interruption group (p < .05). All partial liquid ventilation-treated animals had less lung injury compared with gas-ventilated animals by both histologic and morphometric analysis (p < .05). The lower lobes of all partial liquid ventilation-treated animals demonstrated less damage than the upper lobes, although scores reached significance (p < .05) only in the partial liquid ventilation-conventional ventilation animals. CONCLUSIONS: In this animal model, partial liquid ventilation using conventional or high-frequency ventilation provided rapid and sustained improvements in oxygenation without adverse hemodynamic consequences. Animals treated with partial liquid ventilation-flow interruption had a significantly decreased survival rate vs. animals treated with the other studied techniques. Histopathologic and morphometric analysis showed significantly less injury in the lower lobes of lungs from animals treated with partial liquid ventilation. High-frequency ventilation techniques did not further improve pathologic outcome. PMID- 9366776 TI - Evaluation of a pediatric intensive care residency curriculum. AB - OBJECTIVE: To teach residents to recognize and treat critically ill or injured infants, children, and adolescents in a 1-month, intensivist-designed, second year resident pediatric intensive care rotation curriculum while maintaining optimal patient care and resident educational satisfaction. DESIGN: Descriptive evaluation of an intensivist-designed, second-year resident pediatric intensive care rotation curriculum from September 1994 to May 1996. SETTING: Multispecialty 16-bed pediatric intensive care unit (ICU) staffed by five pediatric critical care physicians in a university-affiliated children's hospital supporting a pediatric residency program. PATIENTS: None. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Our second-year resident pediatric ICU rotation curriculum consisted of direct patient care, participation in clinical rounds under the supervision of a pediatric critical care attending physician, and a 1-month formal curriculum. A standardized test evaluated resident pediatric critical care knowledge before and after the pediatric ICU rotation. Number and type of resident procedures were documented. Four-point Likert scale questionnaires were used to evaluate resident educational satisfaction and resident performance. Opportunity cost, the graduate medical education return on educational investment, the critical care attending physician's return on resident investment, and the optimal teaching time for number of rotation residents were calculated. Unit demographics were documented. Data analysis included multivariate analysis, t-test, and chi-squared techniques. Significance was defined as p < .05, rotated factor loading > 0.5, and Eigenvalues > or = 1. Kmeans identified clusters. From September 1994 to May 1996, 71 residents, 34 (48%) from pediatric or medicine-pediatric programs and 37 (52%) from emergency medicine residency programs, participated in our second-year pediatric ICU resident educational process. All residents showed improvement between pretest and posttest knowledge scores (p < .05). Seventy percent of the variance in critical care attending physician evaluations of the residents during their pediatric ICU rotation was based on bedside clinical skills (31%), communication skills (20%), and basic knowledge base (19%). Critical care attending physician evaluations of residents placed residents into three clusters: "hands-on," "well rounded," or "book-heavy" residents. Prerotation test scores, postrotation test scores, and numbers of procedures performed did not correlate with how critical care attending physicians evaluated overall performances of individual residents. Three factors explained 61% of the variances in resident satisfaction with the pediatric ICU rotation: clinical experience (27%), formal didactics (18%), and text availability (16%). Resident educational satisfaction did not appear to depend on access to procedures. Critical care attending physicians spent a minimum of 12.6 hrs/wk involved in resident education. The opportunity cost for using critical care attending physicians to provide 12.6 resident teaching hours per week was calculated as $111,384/yr. Pediatric ICU patient demographics, morbidity, and mortality did not change during the introduction of the resident educational program in the pediatric ICU. CONCLUSIONS: During a required pediatric ICU resident rotation, balancing the resident's educational and decision-making autonomy needs and the critical care attending physician's desire to provide consistent bedside care of the critically ill child is an ongoing interactive process that requires substantial personnel, time, and financial commitments. It is possible to maintain patient care in the pediatric ICU and provide residents with a satisfying pediatric ICU experience. Trends in financial reimbursement may limit our present time commitment to the resident pediatric ICU curriculum. PMID- 9366777 TI - Comparison of simultaneously obtained arterial and capillary blood gases in pediatric intensive care unit patients. AB - OBJECTIVE: To determine whether capillary blood gas measurements provide a clinically acceptable estimate of arterial pH, PCO2, and PO2. DESIGN: Prospective convenience sample. SETTING: Pediatric intensive care unit at a referral children's hospital. PATIENTS: Fifty children > 1 month of age with indwelling arterial catheters. INTERVENTIONS: A local anesthetic was applied to the third finger of the hand contralateral to a radial artery catheter. After 90 mins, simultaneous arterial and capillary blood gases were drawn. MEASUREMENTS AND MAIN RESULTS: Arterial and capillary pH, PcO2, and PO2 were measured. Heart rate and Wong/Baker faces score were noted before and during capillary blood gas collection to assess discomfort associated with blood collection. There was a strong correlation between capillary and arterial pH (r2 = .903, p < .0001). The relative average bias of the capillary pH was 0.009, with capillary lower than arterial and 95% limits of agreement of +/- 0.032. In all patients, the absolute value of the difference between arterial and capillary pH was < or = 0.05. There was a strong correlation between arterial and capillary PCO2 (r2 = .955, p < .0001). The relative average bias of the capillary PCO2 was 1.6 torr (0.21 kPa), with capillary higher than arterial and 95% limits of agreement of +/- 4.5 torr (+/- 0.6 kPa). In two of 50 patients, the absolute value of the difference between arterial and capillary PCO2 was > 6.5 torr (> 0.87 kPa). Despite a statistically significant correlation between capillary and arterial PO2 (r2 = .358, p < .0001), the absolute value of the difference between arterial and capillary PO2 was > 6.5 torr (> 0.87 kPa) in 42 of 50 patients. Pain, endotracheal intubation, vasoactive drips, or pharmacologic paralysis did not affect accuracy of the capillary pH or PCO2. CONCLUSIONS: Capillary blood gases accurately reflect arterial pH and PCO2 in most pediatric intensive care unit patients. Capillary samples did not significantly underestimate arterial hypercarbia or acidosis. This conservative reflection of metabolic status may be particularly useful in hemodynamically stable patients with mild-to-moderate lung disease. PMID- 9366778 TI - Noninvasive assessment of cardiac output in critically ill patients by analysis of the finger blood pressure waveform. AB - OBJECTIVE: To assess whether the measurement of cardiac output by computer assisted analysis of the finger blood pressure waveform can substitute for the thermodilution method in critically ill patients. DESIGN: Prospective data collection. SETTING: Emergency department in a 2000-bed inner city hospital PATIENTS: Forty-six critically ill patients requiring invasive monitoring for clinical management were prospectively studied. INTERVENTIONS: Under local anesthesia a 7-Fr pulmonary artery catheter was inserted via the central subclavian or jugular vein. Cardiac output was determined by the use of a cardiac output computer and injections of 10 mL ice-cold glucose 5%. Noninvasive cardiac output was calculated from the finger blood pressure waveform by the use of the test software program. MEASUREMENTS AND MAIN RESULTS: Three hundred twenty-three pairs of invasive and noninvasive hemodynamic measurements were collected in intervals of 30 mins from 46 patients (mean age 61.9 +/- 12.4 yrs; 35 male, 11 female). The average cardiac index during the study period was 2.83 L/min/m2 (range 0.97 to 5.56). The overall discrepancy between both measurements was 0.14 L/min/m2 (95% confidence interval: 0.10-.018, p < .001). Seventy-five (23.2%) measurements had an absolute discrepancy > +/- 0.50 L/min/m2. Noninvasive and invasive comparisons of mean differential cardiac output were out of phase for 9.7% of all readings. CONCLUSION: Computer-assisted analysis of finger blood pressure waveform to assess cardiac output is not a substitute for the thermodilution method due to a high percentage (23.2%) of inaccurate readings; however, it may be a useful tool for the detection of relative hemodynamic trends in critically ill patients. PMID- 9366779 TI - How to use articles about harm: the relationship between high tidal volumes, ventilating pressures, and ventilator-induced lung injury. AB - BACKGROUND: Intensivists commonly encounter patients who may be inadvertently harmed by critical care interventions. This article is designed to guide clinicians in the evaluations of an individual article assessing a question of harm, as well as the sum of multiple pieces of evidence. OBJECTIVES: To assess the vaidity of a group of articles about the relationship between high tidal volumes and ventilating pressures on ventilator-induced lung injury; to interpret the results of these studies; and to consider whether they apply in practice. DATA SOURCES: Issues of harm are sometimes measured in randomized trials, but are evaluated more often in myriad observational studies. DATA EXTRACTION: We use critical appraisal guides for experimental studies (e.g., randomized trials) and observational studies (e.g., cohort studies, case-control studies and case series) that evaluate the potentially harmful exposure of high tidal volumes and ventilating pressures. This involves assessing the validity of the research, then determining the strength of association between the putative harmful exposure and adverse outcomes. These study designs and their interpretation using relative risks and odds ratios are reviewed. Finally, the relevance of this information (or lack thereof) to clinical practice needs to be determined. DATA SYNTHESIS: Examining these studies individually and in totality, there appears to be a relationship between high tidal volumes and ventilating pressures, although the strength of inference from this research is limited by design issues and sample sizes. CONCLUSIONS: Critically appraising a body of literature is more challenging than evaluating a single study, but often gives a broader view of the available evidence. Future large, rigorous, randomized trials of different approaches to mechanical ventilation will help to advance our understanding and to better inform our practice. PMID- 9366780 TI - Neurologic disease and the determination of brain death: the importance of a diagnosis. PMID- 9366782 TI - A cost-effective and volume-sparing strategy for continuous benzodiazepine infusions. PMID- 9366781 TI - Life-threatening dysrhythmias in severe thioridazine poisoning treated with physostigmine and transient atrial pacing. AB - OBJECTIVES: To describe clinical, electrocardiographic, and blood chemistry findings in a case of high-dosage thioridazine self-poisoning, focusing on the cellular mechanisms of the cardiovascular toxicity. DESIGN: Case report and literature review. SETTING: Intensive care unit (ICU) of a district hospital in Germany. PATIENT: A 68-yr-old male patient admitted to the ICU for treatment of a severe thioridazine intoxication. INTERVENTIONS: Prevention of absorption (gastric lavage), mechanical ventilation, fluids, alkalinization, catecholamines, drugs (physostigmine, neostigmine), direct current cardioversion/defibrillation, and transient pacemaker (atrial stimulation). MEASUREMENTS AND MAIN RESULTS: Central nervous, cardiovascular, and gastrointestinal systems indicated the adverse side effects of thioridazine intoxication over a period of 9 days. During high toxic thioridazine plasma concentrations (6061 to 6480 ng/mL), a life threatening crisis occurred due to malignant ventricular arrhythmias followed by bradycardia (e.g., sinus node arrest). The electrocardiogram showed delays in all parts of the conduction system of the heart, including prolonged repolarization for several days, which disappeared completely when thioridazine plasma concentrations were within the therapeutic range. CONCLUSIONS: An individual therapeutic approach is needed in cases of thioridazine overdose. The primary aim is to stabilize the cardiac rhythm and the circulation. PMID- 9366783 TI - Gentamicin pharmacokinetics in neonates with patent ductus arteriosus. PMID- 9366784 TI - Vascular surgery in Belgium. PMID- 9366785 TI - Vascular surgery in Switzerland. PMID- 9366786 TI - Treadmill testing for evaluation of claudication: comparison of constant-load and graded-exercise tests. AB - OBJECTIVES: To compare the correlation and practicability of single-stage vs. graded treadmill protocols in the assessment of the absolute claudication distance (ACD). DESIGN: Randomized open study. MATERIAL AND METHODS: In 52 patients with peripheral arterial occlusive disease, the ACD on treadmill at 3 km/h and 12% grade (constant-load test = C-test) ranged form 50 to 400 m. The C test and the graded-exercise test (walking on the treadmill at 3 km/h and 0% gradient for 3 min, with subsequent increase in gradient of 3.5% every 3 min = G test) were carried out at random on the same day under standardized conditions. RESULTS: The ACD was higher in the G-test than in the C-test (360.4 +/- 208.8m vs. 166.5 +/- 93.6m; p < 0.001). The coefficients of variation were very similar (57.9% and 56.2%, respectively). In the subgroup of patients with an ACD of between 100 m and 150 m, a large difference was found both for the coefficient of variation (58.6% G-test, 9.6% C-test) and for the standard deviation (339.8 +/- 199.0m and 133.1 +/- 12.8m, respectively). CONCLUSIONS: For the assessment of the ACD in patients with severe claudication the C-test would seem to be more suitable than the G-test. PMID- 9366787 TI - Reoperations, redo surgery and other interventions constitute more than one-third of vascular surgery. A study from Swedvasc (the Swedish Vascular Registry). The Swedish Society for Vascular Surgery. AB - OBJECTIVES: To describe the incidence of reoperations within 30 days, later redo procedures, and other interventions after vascular procedures. DESIGN: Analysis of vascular procedures prospectively recorded in The Swedvasc Registry. MATERIALS AND METHODS: From 1987 to 1991, 8089 primary interventions were done for acute ischaemia, elective and emergency aortic aneurysms, intermittent claudication, critical leg ischaemia and carotid artery stenosis. Subsequent arterial surgery was identified until the end of 1995. RESULTS: Of an additional 4927 procedures, 24.1% were performed within 30 days of the first operation, 29.6% during the remaining first year, and 14.1%, 10.5% and 8.5% during the following 3 years, respectively. Thus, 15.5-41.5% of patients, depending on the indication, had further vascular surgery within a 4-year period. After operations for acute ischaemia or emergency aortic aneurysms, half of the reinterventions were performed within 30 days. In claudication, critical ischaemia, and after carotid endarterectomy, reinterventions peaked later during the first postoperative year. At 4 years the proportion without repeated surgery was 69%, patient survival 59% and event-free survival 39%. CONCLUSIONS: The considerable risk of reintervention after vascular procedures, and the limited life expectancy of patients, should be considered in treatment decisions for vascular disease. PMID- 9366788 TI - Changes in aortic wall stiffness in men with alpha 1-antitrypsin deficiency. AB - OBJECTIVES: To examine the diameter and distensibility of the abdominal aorta in patients with severe alpha 1-antitrypsin deficiency, and to compare the results with those of normal subjects. MATERIAL AND METHODS: Abdominal aortic diameter and stiffness (beta) was measured using echo-tracking sonography in 19 men (mean age 50, range 25-79) and 17 women (mean age 46, range 26-62) with severe alpha 2 antitrypsin deficiency. The results were compared with those of healthy individuals of corresponding age and gender. RESULTS: There was no significant difference in the abdominal aortic diameter between controls and patients with alpha 1-antitrypsin deficiency when corrected for age, sex and body surface area (men p = 0.20, women p = 0.10). Men with alpha 1-antitrypsin deficiency showed significantly lower stiffness in the abdominal aorta compared to controls (p = 0.025), whereas women did not (p = 0.17). CONCLUSIONS: No significant difference in abdominal aortic diameter could be detected in patients with alpha 1 antitrypsin deficiency compared with controls. However, aortic distensibility in men with alpha 1-antitrypsin deficiency is altered. This may reflect early vessel wall abnormality. PMID- 9366789 TI - The mechanical properties of elastic arteries in Ehlers-Danlos syndrome. AB - OBJECTIVE: To study whether measurements of wall mechanics can be used as an indicator of disturbed vessel wall integrity and predictor of vessel fragility in Ehlers-Danlos Syndrome (EDS). METHODS: The wall mechanics of the abdominal aorta (AO) and common carotid artery (CCA) were estimated from the indices Ep (pressure strain elastic modulus) and stiffness (beta) in twelve individuals with EDS of different subtypes and compared with the results of a healthy reference population. Ep and beta were calculated from diameter and pulsatile diameter change determined non-invasively with the aid of an ultrasonic echo-tracking system and blood pressure obtained by the auscultatory method. RESULTS: Compared with normal individuals and their confidence intervals, subjects with EDS had unaltered diameter, Ep and beta in the AO, as well as in the CCA. Analysis of covariance (ANCOVA) also showed unaltered results. AO: diameter (males p = 0.66, females p = 0.27), Ep (males p = 0.81, females p = 0.27) and beta (males p = 0.95, females p = 0.12). CCA: diameter (males p = 0.36, females p = 0.46), Ep (males p = 0.93, females p = 0.48) and beta (males p = 0.86, females p = 0.47). CONCLUSIONS: This investigation could not demonstrate any alteration in wall mechanics as a sign of disturbed vessel wall integrity of elastic arteries in EDS. This might indicate that the structural defect in the arterial wall collagen, and thus the tendency to vessel fragility, cannot be revealed under normal physiological pressure conditions. PMID- 9366790 TI - Endovascular AAA treatment: expensive prestige or economic alternative? AB - OBJECTIVES: To compare the costs of endovascular aneurysm treatment versus open surgery during the perioperative period. METHODS: Retrospective analysis of a consecutive series of 44 patients undergoing infrarenal abdominal aneurysm repair from February 1995 to March 1996 at a university teaching hospital. RESULTS: No endovascular procedure was converted to open repair. Operative time was shorter for endovascular treatment (207.6 min vs. 229.1 min, n.s.), as well as postoperative intensive care unit stay (ICU, 22.7 h vs. 55.0 h, p = 0.017) and the postoperative recovery period (5.6 days vs. 13.3 days, p < 0.001). Open surgery generated significantly more costs (25,374.07 ECU vs. 22,268.78 ECU, p < 0.001), despite evaluation and a more expensive endovascular procedure (10,699.48 ECU vs. 4032.01 ECU, p < 0.001). During the study, costs for open surgery exceeded the cost for endovascular treatment by 13.95%. CONCLUSIONS: Endovascular aneurysm treatment is cost effective and less expensive than open surgery. The main reason for cost saving is faster patient recovery after surgery, associated with a shorter LOS in the patients treated with endovascular procedure. PMID- 9366791 TI - Effects of vascular surgery on amputation rates and mortality. AB - OBJECTIVES: To study the relation between rates of vascular interventions, amputations and mortality in a defined population. DESIGN: Retrospective comparison between two consecutive 4-year periods. SETTING: Swedish district hospital covering a population of 125,000. MATERIAL: Three hundred and sixty seven lower limb amputations and 1080 vascular procedures. RESULTS: The number of legs treated for limb-threatening ischaemia with either revascularisation or amputation increased from 269 to 289. The rate of vascular interventions for limb threatening ischaemia increased from the first to the second period by 65%, while the rate of amputations decreased by 23%. Limb salvage rate at 30 months increased from 37% to 53% (p < 0.0000). The reduced amputation rate was entirely related to primary amputations. The adjusted risk of amputation for patients treated in the second period was half of that for patients treated in the first period (relative risk = 0.49, p = 0.0001), while mortality was similar in both periods. Among survivors, the proportion of patients with intact legs was higher in the second period than in the first, while no difference was found between the two periods among deceased patients. CONCLUSIONS: Increased vascular intervention leads to improved limb salvage rates and reduced amputation rates. It is important for both ethical and economical reasons to identify good responders to revascularisation, because the choice of initial treatment will only influence limb salvage but not survival. PMID- 9366792 TI - Haemodynamics of patients with severe lower limb arterial disease: the critical aspects of critical ischaemia. AB - OBJECTIVES: To compare the value of ankle and toe pressures as regards the diagnosis of critical ischaemia, its prognosis, and the need for vascular surgery. DESIGN: University hospital-based retrospective study. MATERIALS AND METHODS: Fifty-seven patients (23 women and 34 men) with gangrene or rest pain had a haemodynamic evaluation combining ankle systolic pressure, toe pressure and cutaneous oximetry (tcPO2) with long-term follow-up (until death, for 44%). RESULTS: After 2 years of follow-up, actuarial rates were 49 and 79% for survival and limb salvage, respectively. Ankle and toe pressures gave rise to different subsets of patients, p < 0.001, mainly because of the existence of a group of patients with very distal foot arterial disease. Low ankle pressure was linked to the risk of major amputation. Low toe pressure was linked to a great need for vascular surgery. Diabetes increased the risk of minor amputation. CONCLUSIONS: The concept of critical ischaemia remains clinically relevant. Haemodynamic quantitative data strengthen this concept, but ankle and toe pressures are not interchangeable parameters. For these reasons, toe pressures should be changed from a recommended to a mandatory haemodynamic parameter in the definition of critical ischaemia. PMID- 9366794 TI - What is the long-term outcome for patients with very small abdominal aortic aneurysms? AB - OBJECTIVE: To determine the long-term outcome for patients with abdominal aortic aneurysms (AAA) less than 4 cm in AP diameter (very small AAA). DESIGN: Population-based screening study. MATERIALS AND METHODS: One hundred and forty two patients who had AAA less than 4 cm at presentation were assessed by ultrasound at intervals of 6-12 months. The records of these patients were reviewed. RESULTS: During the period of follow-up the median annual growth rate for aneurysms while under 3.0 cm was 1 mm, rising to 2 mm when between 3.0 and 3.9 cm, and 3 mm when between 4.0 and 4.9 cm in diameter. Elective aneurysm repair was undertaken when aneurysms exceeded the threshold value, which itself increased from 4 cm to 5.5 cm in the 9 years of follow-up. More patients died with their aneurysm (n = 35) then underwent surgery (n = 23). There was one perioperative death, and three unrelated late deaths after resection. One aneurysm ruptured in a patient who had refused follow-up 5 years previously. CONCLUSIONS: This study suggests that aneurysms less than 4.0 cm diameter are relatively benign, and questions the appropriateness of early intervention. PMID- 9366793 TI - Anti-angiogenic drug AGM1470 suppresses smooth muscle cell migration induced by endothelial PDGF. AB - OBJECTIVES: To examine the effects of the anti-angiogenic drug AGM1470 on smooth muscle cell (SMC) migration activity stimulated by endothelial cell (EC)-derived mitogen. MATERIALS AND METHODS: Study 1; EC's were cultured under pulsatile flow using MCDB151 medium. From the supernatant of these EC dishes we devised two types of conditioned medium; anti-PDGF(+) containing 10 micrograms/ml anti-PDGF antibody, and anti-PDGF(-) containing no antibody. SMC's were cultured using both media. Study 2; EC's were cultured under the same conditions using both types of medium; MCDB151 medium containing 10 ng/ml AGM1470, and MCDB151 medium alone. After the AGM1470 concentration had been adjusted to 10 ng/ml, SMC's were cultured using each medium; AGM-exposed EC and AGM-non-exposed EC. SMC colony spreading distances were measured as an index of mitogenic activity for 4 days. RESULTS: Study 1; the anti-PDGF(-) group showed an apparently greater spreading distance than the anti-PDGF(+) group. Study 2; the AGM-non-exposed EC group showed a significantly greater spreading distance than the AGM-exposed EC group. However, MTT assay revealed no differences in proliferation between the two groups. CONCLUSION: AGM1470 suppresses the EC production of this PDGF-like mitogen as well as SMC migration activity. PMID- 9366795 TI - Evaluation of colour duplex ultrasound scanning in diagnosis of renal artery stenosis, compared to angiography: a prospective study on 53 patients. AB - OBJECTIVES: To evaluate the accuracy of colour Duplex ultrasound scanning compared to angiography in the diagnosis of renal artery stenosis. DESIGN: A prospective study. MATERIALS: A selected series of 53 unselected patients, who had both sonography and angiography. METHODS: Sonographic examinations were performed by the same operator, who was unaware of angiographic results. Angiography was interpreted without knowledge of the sonographic findings. Peak systolic velocity and acceleration time were sonographic criteria. In contrast to the other studies, inadequate examinations were not repeated, nor drawn out from analysis. RESULTS: On 112 arteries visualised by angiography, 103 were detected by sonography. Feasibility was 78.6% for complete examinations. On 16 stenoses identified by angiography, 12 were detected by sonography, leading to a 75.0% sensitivity and a 100% specificity. CONCLUSIONS: This study was elaborated with a pragmatic attitude similar to clinical practice, and the results achieved were equal to those of other series. Accessory arteries are poorly visualised; limits of this technique are due to the operator's training and patient's poor condition for undergoing sonographic examination. These limiting factors mean a loss of sensitivity, which precludes a diagnostic decision, when the result is negative. PMID- 9366796 TI - Variations of rates of vascular surgical procedures for chronic critical limb ischaemia and lower limb amputation rates in western Swedish counties. The Westcoast Vascular Surgeons (WVS) Study Group. AB - OBJECTIVE: To assess a possible covariation between vascular surgery and amputation rates for critical limb ischaemia in defined western Swedish populations. DESIGN AND SETTING: A retrospective study during 1 year of the total number of vascular reconstructions for chronic critical leg ischaemia and amputations in the western Sweden area of health care. MAIN OUTCOME MEASURES: Correlation between vascular reconstruction and amputation rates in subpopulations. RESULTS: Patients undergoing amputation were 6 years older and had a significantly higher degree of dependent living compared with those subjected to revascularisation. The annual vascular reconstruction rate for critical limb ischaemia varied between 2 and 45, and the amputation rate between 12 and 71 per 100,000 population in the different catchment areas. There was, however, no negative correlation between amputation and revascularisation rates. CONCLUSION: We failed to demonstrate a negative correlation between amputation and revascularisation rates. Patients undergoing vascular reconstruction and amputation may represent different populations. Catchment areas with high vascular surgical activity did not have correspondingly lower amputation rates. PMID- 9366797 TI - Superficial femoral vein graft donation from the amputated limb. PMID- 9366798 TI - Three-dimensional reconstruction by spiral computed tomography to locate aortic tear following blunt abdominal trauma. PMID- 9366799 TI - Duplex ultrasound and angiography. PMID- 9366801 TI - Iloprost. PMID- 9366800 TI - Vein graft surveillance. PMID- 9366802 TI - Transcranial Doppler. PMID- 9366803 TI - Buerger's disease. PMID- 9366804 TI - Vascular dementia: the need for a new approach. PMID- 9366805 TI - The genetics and pathophysiology of Alzheimer's disease. PMID- 9366806 TI - The prevention or treatment of age-related osteoporosis in the elderly by systemic recombinant growth factor therapy (rhIGF-I or rhTGF beta): a perspective. AB - Both insulin-like growth factor-I (IGF-I) and transforming growth factor beta (TGF beta) have powerful modulatory effects in a variety of tissues. A major target of action is the skeletal system, where they enhance bone formation and decrease matrix degradation, thus playing a part in the maintenance of bone mass. Because of the potent mitogenic effect of these agents on osteoblasts, recombinant IGF-I (rhIGF-I) and recombinant TGF beta (rhTGF beta) have potential as drugs to stimulate bone formation in the prevention and treatment of osteoporosis. Using biochemical markers, subcutaneous rhIGF-I therapy has been shown to increase bone turnover and bone formation in nonosteoporotic older people. However, a corresponding increase in bone mass has not yet been documented nor have there been reports yet on the effects of systemically administered rhTGF beta in humans. Further investigation is required to define the clinical potential of rhIGF-I and rhTGF beta as therapeutic agents in age related osteoporosis. PMID- 9366807 TI - The interaction between age and comorbidity contributes to predicting the mortality of geriatric patients in the acute-care hospital. AB - OBJECTIVE: To test the predictive power of comorbidity and of the interaction between age and comorbidity in geriatric patients with acute medical illness. DESIGN: Prospective observational study. SETTING: Medical and geriatric wards of an acute-care hospital. SUBJECTS: Three hundred and seventy patients over 70 years of age consecutively admitted in an 18-month period. MAIN OUTCOME MEASURE: In-hospital mortality. METHOD: On admission a multidimensional assessment was performed, and a comorbidity index and an age-comorbidity index developed on a comparable training population were calculated. The comorbidity index is based upon a scoring system that quantifies the prognostic weight of individual diseases, while the age-comorbidity index corrects the former for the age-related increase of the risk of death. The predictive power of variables univariately correlated with the outcome was tested by logistic regression. RESULTS: Death was independently predicted by clinical diagnosis of malnutrition (odds ratio = 1.87, confidence limits CL = 1.20-2.86), age-comorbidity index > 7 (odds ratio = 1.77, CL = 1.15-2.72), preadmission impairment in activities of daily living (odds ratio = 1.74, CL = 1.13-2.69), lymphocytopenia (odds ratio = 1.74, CL = 1.15 2.61). A weaker predictive model was obtained by substituting the comorbidity index for the index of age-comorbidity. Excluding comorbidity from the logistic regression greatly weakened the predictive model. PMID- 9366808 TI - Social and biological predictors of early menopause: a model for premature aging. AB - OBJECTIVES: To investigate possible social, lifestyle-related and biological predictors of early menopause in middle-aged women, followed prospectively for 11 years. DESIGN: A prospective, population-based, cohort follow-up, observational study. SETTING: Glostrup Hospital, Copenhagen, Denmark. SUBJECTS: A total of 493 female subjects, all aged 40 years at baseline, and divided into three groups according to self-reported menopausal age (40-45, 46-51, 51+ years), after 12 months of amenorrhoea. Women having had medical or surgical interventions to influence menopausal state were excluded. MAIN OUTCOME MEASURES: Body mass index, glucose, insulin, lipids, creatinine, uric acid, thyroid-stimulating hormone (TSH), lung function tests (forced VC, FEV1, peak flow), blood pressure; a self administered questionnaire with questions on psychosocial variables, lifestyle, and self-rated health. RESULTS: An early menopausal age correlated in an univariate way with impaired lung function, increased smoking habits and low social class (in childhood or present), as well as with a feeling of tiredness, all measured at the baseline investigation. On the contrary, a later menopausal age correlated with higher serum insulin and uric acid levels. In multiple regression analysis, with menopausal age as the dependent variable, it was found that smoking habits (number of years smoking) was inversely (P < 0.001), and insulin as well as uric acid were positively (P < 0.05) correlated with menopausal age. CONCLUSIONS: Females who smoke run an increased risk of early menopause, whereas relative hyperinsulinaemia is independently associated with later menopause. At the age of 40 years, high insulin levels in females might be just a marker for normal female sex hormone physiology, not for insulin resistance, as seen in postmenopausal female subjects. Early menopause might be useful as a potential model of premature ageing. PMID- 9366809 TI - Brain natriuretic peptide in an elderly population. AB - OBJECTIVES: To study the relationship of brain natriuretic peptide concentrations to ageing, and whether brain natriuretic peptide could reflect current disease states in the general elderly population. DESIGN: Brain natriuretic peptide was measured in two population samples from the general population. SUBJECTS: Five hundred forty-five 85-year-old subjects from the longitudinal population study '70-year-old people in Gothenburg, Sweden' were investigated in respect to cardiovascular, renal and metabolic disease, and 191 subjects from the 40-year old male population were examined. MAIN OUTCOME MEASURES: To study the influence of ageing on circulating brain natriuretic peptide and the association between concentrations of brain natriuretic peptide and common disease states in the elderly. RESULTS: Brain natriuretic peptide concentrations were significantly increased in relation to ageing (P < 0.001). Brain natriuretic peptide concentrations were significantly increased in elderly with congestive heart failure (P < 0.001), ischaemic heart disease (P < 0.001), atrial fibrillation (P < 0.001) and renal dysfunction (P < 0.001) but not in hypertension. In multivariate analysis, brain natriuretic peptide concentrations were predictive for ischaemic heart disease (P < 0.001), atrial fibrillation (P < 0.01), renal dysfunction (P < 0.01), congestive heart failure (P < 0.05) and treatment with beta-adrenergic blockers (P < 0.05). CONCLUSIONS: Plasma concentrations of brain natriuretic peptide are increased in healthy elderly compared to middle-aged individuals. In the elderly, measurements of brain natriuretic peptide may provide prognostic information, due to the augmented secretion in cardiovascular diseases commonly seen in this population. It remains to be determined whether routine measurements of circulating brain natriuretic peptide will be of value in predicting current cardiovascular disease for the individual patient. PMID- 9366810 TI - Cognitive function, vascular risk factors and education. A cross-sectional study based on a cohort of 70-year-old men. AB - OBJECTIVES: A low level of education is associated with an increased risk of developing a dementia disorder, as well as with a higher risk of cardiovascular disease. The aim of this study was to investigate the association between education and cardiovascular risk factors, and to study the relation between these factors and cognitive function in elderly men. DESIGN: Cross-sectional population-based study. SETTING: Uppsala, Sweden. SUBJECTS: 504 men aged 69-74 years, participants in a longitudinal health survey concerning cardiovascular risk factors. MAIN OUTCOME MEASURE: Cognitive function as measured by a composite score of 13 standard psychometric tests. RESULTS: A low level of education was associated with poorer cognitive performance, as well as with obesity, smoking, diabetes, high concentrations of serum triglycerides and plasma fibrinogen. In the entire cohort, subjects with obesity, smoking, diabetes or hypertriglyceridaemia showed impaired cognitive test results, independent of socio-economic factors. When stroke cases were excluded, obesity and smoking were still related to impaired cognitive function. CONCLUSIONS: Smoking and obesity with associated metabolic disturbances are inversely related both to educational level and to cognitive function. Cognitive decline of vascular origin is potentially preventable by treatment of risk factors. The question of whether the increased vascular risk contributes to the higher prevalence of cognitive disorders in individuals with low socio-economic status, needs to be further evaluated in longitudinal population-based studies. PMID- 9366811 TI - The accuracy of peripheral skeletal assessment at the radius in estimating femoral bone density as measured by dual-energy X-ray absorptiometry: a comparative study of single-photon absorptiometry and computed tomography. AB - OBJECTIVES: One of the latest developments in bone densitometry is peripheral quantitative computed tomography (pQCT), a method which allows the separate determination of cortical and trabecular bone mineral density (BMD) in the peripheral skeleton. This study was designed to compare the relative abilities of single-photon absorptiometry (SPA) and pQCT to reflect BMD of the proximal femur as measured by dual-energy X-ray absorptiometry (DXA), an established predictor of osteoporotic hip fracture risk. DESIGN: Cross-sectional study. SUBJECTS: A well-defined community-based sample of 129 skeletally healthy women aged 70-87 years. MEASUREMENTS: Radial BMD by SPA and pQCT and femoral BMD by DXA. Univariate and multivariate regression analyses were performed relating the DXA measurements at the femoral neck and the trochanteric region with the values of SPA and pQCT. RESULTS: Approximately 38% of the variance in femoral neck BMD could be explained by BMD of the midradius assessed by SPA, in contrast to only 18-27% by pQCT. At the trochanter, 32% of BMD could be predicted by SPA as compared to 19-26% by pQCT. Moreover, according to multiple regression, prediction of femoral BMD by SPA was not enhanced by performing pQCT. CONCLUSIONS: Radial pQCT has little value as a screening tool to identify elderly women with low femoral BMD. Additional research is needed to determine whether or not pQCT will enhance fracture prediction beyond that obtainable from a density measurement by SPA. PMID- 9366812 TI - The influence of age on low density lipoprotein metabolism: effects of cholestyramine treatment in young and old healthy male subjects. AB - OBJECTIVE: The plasma concentration of low density lipoproteins (LDL) increases with age, mainly as the result of a reduced clearance of LDL. Because the conversion of cholesterol to bile acids is reduced with age, we hypothesized that the response of plasma LDL to stimulation of bile acid production would be different in young and old subjects. DESIGN, SUBJECTS AND SETTING: Comparison of the response to cholestyramine treatment in two groups of normolipidaemic, normal weight males: seven young (23-34 years) and eight old (64-73 years). Outpatients at the metabolic ward of a university hospital given a standardized diet of natural type. INTERVENTION: Cholestyramine was given 8 g b.i.d. for 3 weeks and continued during the second LDL turnover study. MAIN OUTCOME MEASURES: Kinetics of autologous radiolabelled LDL before and during treatment. Mean values of lipoprotein lipid levels obtained during the two turnover studies. Changes in LDL particle composition and LDL receptor affinity between the two study periods. RESULTS: Both age groups responded with decreased levels of LDL cholesterol and apolipoprotein-B (apoB), the change being more pronounced in the old subjects. The LDL apoB fractional catabolic rate was increased by approximately 11% in both groups. In contrast, there was a reduced ability in the old subjects to sustain their production rates for LDL apoB with resin therapy, resulting in a 23% reduction in LDL input. No effect on the apparent LDL apoB synthesis rate was observed in the young subjects. LDL particles isolated from cholestyramine treated subjects were triglyceride-enriched and cholesterol-depleted, and showed a lowered affinity for the LDL receptor in tissue culture studies. CONCLUSIONS: The results demonstrate that stimulation of bile acid production by cholestyramine treatment decreases LDL cholesterol levels in both young and old subjects. This therapy increases LDL apoB elimination in both age groups, but reduction of apparent LDL apoB production is only seen in old subjects. PMID- 9366813 TI - Homocysteine, atherosclerosis and prevalent cardiovascular disease in the elderly: The Rotterdam Study. AB - OBJECTIVES: Elevated homocysteine increases the risk of vascular disease, in particular amongst younger subjects (< 60 years). Very few studies have been performed amongst older subjects. We evaluated the relation of plasma total homocysteine (tHcy) to atherosclerosis and symptomatic cardiovascular disease amongst older men and women. DESIGN: A cross-sectional study. SETTING: General population. SUBJECTS: A random sample of 630 men and women, participating in the Rotterdam Study, a prospective population-based cohort study amongst 7983 subjects aged 55 years and over residing in the Ommoord district of Rotterdam, the Netherlands. MAIN OUTCOME MEASURES: Carotid atherosclerosis (carotid plaques and common carotid intima-media thickness) assessed by ultrasonography; lower extremity (peripheral) artery atherosclerosis measured by the ratio of the ankle to arm systolic blood pressure; prevalent cardiovascular disease assessed as a history of myocardial infarction or stroke. RESULTS: Subjects, 55-74 years of age, with elevated tHcy levels (+/- 18.6 mumol L-1) had a thicker common carotid intima-media (difference 0.037 mm; 95% CI 0.001, 0.073), a lower ankle-arm index (-0.054; -0.104, -0.004), and an increased risk of cardiovascular disease (odds ratio 3.0; 1.5, 6.1), after adjusting for sex and age. There was no appreciable association of tHcy levels to atherosclerosis and cardiovascular disease in subjects aged 75 years and older. CONCLUSIONS: In subjects aged 55-74 years elevated tHcy is associated with an increased risk of atherosclerosis and cardiovascular disease. The lack of association in those aged > or = 75 years most probably reflect selective mortality. PMID- 9366814 TI - Purpura in infants and children. AB - Hemorrhage into the skin (purpura) may result from abnormalities in any of the three components of hemostasis: platelets, plasma coagulation factors, and blood vessels. The morphology, size, and distribution of the hemorrhagic lesions are helpful diagnostic features. The main causes of purpura in the newborn and the more common hemorrhagic disorders in children are reviewed. PMID- 9366815 TI - Long-term results after CO2 laser skin resurfacing: a comparison of scanned and pulsed systems. AB - BACKGROUND: New laser technology permits the use of high-energy pulsed and continuous-wave carbon dioxide (CO2) lasers with flashscanners to treat rhytides. OBJECTIVE: We compared the efficacy and side effects of the two leading CO2 lasers used in skin resurfacing. METHODS: A total of 28 patients with facial rhytides were treated with either the UltraPulse or SilkTouch laser systems; in five additional patients, contralateral cosmetic units were treated with one system or the other in a direct comparison of the lasers. RESULTS: We compared photographs taken before and after treatment, and a lessening of facial wrinkling was noted in all subjects. In some subjects improvement was confirmed by optical profilometry methods. Biopsy specimens in representative patients showed that immediate thermal damage was limited to 180 microns. Long-term postoperative specimens showed changes in the papillary dermis consistent with new collagen deposition and reduction of pretreatment solar elastosis. Posttreatment facial erythema was noted in half the patients for up to 2 months; transient hyperpigmentation was observed in one third of the treated areas. CONCLUSION: Although the SilkTouch system produced more immediate thermal damage, there were no significant differences in efficacy or adverse effects between the lasers. Our results suggest that both laser systems, used with appropriate settings, are capable of safely smoothing the skin surface. PMID- 9366816 TI - Procedures for skin diseases performed by physicians in 1993 and 1994: analysis of data from the National Ambulatory Medical Care Survey. AB - BACKGROUND: The provision of ambulatory dermatologic procedural care is not well characterized. OBJECTIVE: Our purpose was to determine the frequency that different cutaneous procedures are performed by different physician specialties and the diagnoses corresponding to these procedures. METHODS: Outpatient dermatologic procedures recorded in the 1993 and 1994 National Ambulatory Medical Care Survey were analyzed. To define dermatologic procedures and diagnoses, the International Classification of Diseases diagnosis and procedure codes were identified that related to the skin and subcutaneous tissues. Sampling weights were applied to achieve the nationally representative estimates. RESULTS: During 1993 and 1994, an estimated 37 million dermatologic procedures were performed. Most were performed by dermatologists (69%) and by family and general practice physicians (15%). A single procedure, "Other local excision or destruction of lesion or tissue of skin and subcutaneous tissue," constituted 65% of all of the dermatologic procedures. UV light treatments, ambulatory microscopic examination of skin specimens, and acne surgical procedures were performed almost exclusively by dermatologists. Most skin biopsies (82%) and excision/destruction procedures (71%) were performed by dermatologists. Actinic keratoses and viral warts accounted for 25% of all cutaneous dermatologic diagnoses treated. CONCLUSION: Dermatologists have far more experience performing skin biopsies and excision/destruction procedures than other physicians. Cost containment efforts that deny coverage for treatment of actinic keratoses and viral warts would affect a significant portion of cutaneous procedures. PMID- 9366817 TI - Evaluation of sunscreens with various sun protection factors in a new transgenic mouse model of cutaneous photoaging that measures elastin promoter activation. AB - BACKGROUND: Long-term sun exposure can cause major alterations in the papillary dermis, resulting in the deposition of massive amounts of abnormal elastic material, termed solar elastosis. Previous work has demonstrated that this type of photodamage is accompanied by an increase in elastin and fibrillin messenger RNAs and elastin promoter activity. OBJECTIVE: Our purpose was to develop a rapid and sensitive in vivo method for evaluating compounds offering protection against cutaneous photodamage. METHODS: Using a line of transgenic mice that expresses the human elastin promoter linked to a chloramphenicol acetyltransferase reporter gene, we applied sunscreens with various sun protection factors to 5-day-old mice followed by 30 minimal erythema doses of solar simulating radiation for three consecutive days. RESULTS: Solar simulating radiation alone resulted in a fivefold increase in elastin promoter activity. Sun protection factors of 2, 4, 8, and 15 yielded a reduction in promoter activity by 2.8%, 42.5%, 58.1%, and 70.3%, respectively. CONCLUSION: These results confirm the use of this system as a rapid and sensitive in vivo model for evaluating compounds that protect against photodamage. PMID- 9366818 TI - Ovarian malignancy in patients with dermatomyositis and polymyositis: a retrospective analysis of fourteen cases. AB - BACKGROUND: Dermatomyositis and polymyositis can be associated with an underlying malignancy. OBJECTIVE: Our purpose was to describe a group of patients with dermatomyositis and polymyositis in whom ovarian carcinoma was diagnosed and to evaluate further the characteristics of the association between these diseases. METHODS: A cross-sectional retrospective review identified 14 patients in a 45 year period (1950 to 1995) with dermatomyositis and polymyositis in whom an underlying ovarian malignancy was diagnosed. Clinical and laboratory data of these patients were reviewed, and immunofluorescent and hematoxylin-eosin-stained skin sections were examined. RESULTS: The mean age at diagnosis of dermatomyositis and polymyositis was 59 years. Of the 14 patients, 11 had dermatomyositis, two had polymyositis, and one had an overlap disease. The 12 patients with dermatomyositis had distinctive cutaneous lesions. In eight, cutaneous biopsy specimens demonstrated variable histologic changes. Thirteen patients had signs of proximal muscle weakness, and myopathy was further demonstrated by electromyographic testing in 10. Creatine kinase levels were increased in 6 of the 10 patients tested. Dysphagia was present in five patients, but esophageal dysmotility was not demonstrated in three. Dermatomyositis and polymyositis preceded the ovarian malignancy in nine patients, were concomitant with it in four, and succeeded the ovarian disease in one. CONCLUSION: Physical examination and imaging techniques failed to detect early ovarian cancer in our patients with dermatomyositis and polymyositis. When detected (usually by abdominopelvic examination, in two by computed tomographic examination), it was advanced, and survival was poor. PMID- 9366819 TI - Merkel cell carcinoma: analysis of clinical, histologic, and immunohistologic features of 132 cases with relation to survival. AB - BACKGROUND: Merkel cell carcinoma (MCC) is an uncommon malignancy of the skin and has a high rate of recurrence and metastasis. There have been few large studies of the biologic behavior of MCC. OBJECTIVE: Our purpose was to determine whether there were clinical or histologic features of MCC that predict its biologic behavior. METHODS: We reviewed 132 cases of MCC. Clinical and histologic features were correlated with follow-up information to determine whether any of these were associated with prognosis. RESULTS: Clinical information was available on 126 patients; 57 were alive, 1 was alive with tumor, 28 died of tumor, 27 died from other causes, and 14 were lost to follow-up. MCC on the buttock/thigh area or trunk had the worst prognosis, and those on the distal extremities had the best prognosis; however, the difference was not statistically significant. Sex and age were not significant factors. Small cell size, high mitotic rate, and large tumor size were associated with a low survival rate. When cell size was excluded, male sex and depth of invasion were associated with a worse survival, although these were not statistically significant. CONCLUSION: Cell size, mitotic rate, and tumor size are significant factors in relation to the biologic behavior of MCC. PMID- 9366820 TI - Oral terbinafine in the treatment of toenail onychomycosis: North American multicenter trial. AB - BACKGROUND: Onychomycosis is an increasing problem with limited therapeutic options. OBJECTIVE: We evaluated the safety and efficacy, of oral terbinafine, a new fungicidal antimycotic, in patients with toenail onychomycosis. METHODS: A North American multicenter, double-blind, placebo-controlled study evaluated the mycologic and clinical efficacy of oral terbinafine 250 mg/day for 12 or 24 weeks in 358 patients with toenail onychomycosis. RESULTS: A total of 74% of patients treated with 12 or 24 weeks of terbinafine achieved a successful clinical outcome. Approximately 11% of terbinafine responders showed evidence of relapse 18 of 21 months after cessation of treatment. Terbinafine was well tolerated; most adverse events were transient and mild to moderate in severity. CONCLUSION: The results of this study confirm that oral terbinafine is a safe and effective therapy for the treatment of onychomycosis. PMID- 9366822 TI - Recurrence rates of excised keloids treated with postoperative triamcinolone acetonide injections or interferon alfa-2b injections. AB - BACKGROUND: Keloids that are surgically removed commonly recur within the excision sites. OBJECTIVE: Our purpose was to determine whether postsurgical adjunctive therapy reduces such recurrences. METHODS: We determined the rate of recurrence after excision alone (n = 43) and postoperative injection with triamcinolone acetonide (TAC; n = 65) or interferon alfa-2b (IFN-alpha 2b; n = 16). RESULTS: Of lesions excised without postoperative injections, 51.1% (22 of 43) recurred; 58.4% of TAC-treated lesions (38 of 65) recurred and 18.7% of IFN alpha 2b-treated lesions (3 of 16) recurred (p = 0.025). CONCLUSION: Postoperative TAC injections do not reduce the number of keloid recurrences. However, injection of keloid excision sites with IFN-alpha 2b offers a therapeutic advantage over keloid excision. PMID- 9366823 TI - Usefulness of the staged excision for lentigo maligna and lentigo maligna melanoma: the "square" procedure. AB - BACKGROUND: Management of lentigo maligna (LM) and lentigo maligna melanoma (LMM) may present problems because of the characteristic, yet unpredictable, subclinical peripheral and periadnexal extension of atypical junctional melanocytic hyperplasia beyond the visible margins. OBJECTIVE: We used paraffin embedded (permanent) peripheral vertical section margin control in a staged fashion in the management of LM and LMM. METHODS: We used a modification of surgical excision in a staged fashion by means of a two-bladed knife with permanent peripheral vertical section margin control. RESULTS: This method is technically easy and results in complete histologic evaluation of the peripheral margins without compromising the measurement of tumor thickness of the primary melanoma. CONCLUSION: The use of the "square" procedure, a staged excision with permanent peripheral vertical section margin control, is useful in the management of LM and LMM. PMID- 9366821 TI - Effectiveness of norgestimate and ethinyl estradiol in treating moderate acne vulgaris. AB - BACKGROUND: An excess of androgen is believed to contribute to development of acne in some patients. Because oral contraceptives (OCs) may reduce the active androgen level, hormonal therapy with OCs has been used successfully to treat patients with acne, although this treatment has previously not been studied in placebo-controlled trials. OBJECTIVE: Our purpose was to evaluate the efficacy of a triphasic, combination OC (ORTHO TRI-CYCLEN [Ortho-McNeil Pharmaceutical, Raritan, N.J.], norgestimate/ethinyl estradiol) compared with placebo in the treatment of moderate acne vulgaris. METHODS: Two hundred fifty-seven healthy female subjects, 15 to 49 years of age with moderate acne vulgaris, were enrolled in a multicenter, randomized, double-blind, placebo-controlled clinical trial. Each month for 6 months, subjects received either 3 consecutive weeks of the OC (i.e., tablets containing a fixed dose of ethinyl estradiol [0.035 mg] and increasing doses of norgestimate [0.180 mg, 0.215 mg, 0.250 mg]) followed by 7 days of inactive drug or placebo (color-matched tablets). Efficacy was assessed by facial acne lesion counts, an investigator's global assessment, a subject's self-assessment, and an analysis of within-cycle variation (cycle 6) in lesion counts. RESULTS: Of the 160 subjects in whom efficacy could be evaluated, the OC group showed a statistically significantly greater improvement than the placebo group for all primary efficacy measures. The mean decrease in inflammatory lesion count from baseline to cycle 6 was 11.8 (62.0%) versus 7.6 (38.6%) (p = 0.0001), and the mean decrease in total lesion count was 29.1 (53.1%) versus 14.1 (26.8%) (p = 0.0001) in the OC and placebo groups, respectively. In the investigator's global assessment, 93.7% of the active treatment group versus 65.4% of the placebo group were rated as improved at the end of the study (p < 0.001). Six of the seven secondary efficacy measures (total comedones, open comedones, closed comedones, papules, pustules, and the subject's self-assessment of study treatment) were also significantly more favorable in the OC group compared with the placebo group. CONCLUSION: An OC containing 0.035 mg of ethinyl estradiol combined with the triphasic regimen of norgestimate is a safe and effective treatment of moderate acne vulgaris in women with no known contraindication to OC therapy. PMID- 9366824 TI - Cytochrome P-450 3A: interactions with dermatologic therapies. AB - Recent case reports and studies suggest that interactions involving the cytochrome P-450 mixed function oxidase system are important causes of medication toxicity and decreased efficacy during combination drug therapy. The cytochrome P 450 3A3/4 isoenzyme is involved in many significant drug interactions. New and familiar drugs continue to be implicated as having potentially serious interactions with this group of enzymes. An understanding of the basic principles of these interactions may have a major impact on patient outcome. PMID- 9366825 TI - American Academy of Dermatology 1997 Awards for Young Investigators in Dermatology. Signal transduction and regulation of angiogenesis. PMID- 9366826 TI - American Academy of Dermatology 1997 Awards for Young Investigators in Dermatology. Mutational analysis of the bullous pemphigoid antigen 2/type XVII collagen gene in patients with generalized atrophic benign epidermolysis bullosa. PMID- 9366827 TI - American Academy of Dermatology 1997 Awards for Young Investigators in Dermatology. The role of Engrailed-1 in limb development and skin patterning. PMID- 9366828 TI - American Academy of Dermatology 1997 Awards for Young Investigators in Dermatology. Pathogenesis of Bartonella henselae in cutaneous and systemic disease. PMID- 9366829 TI - American Academy of Dermatology 1997 Awards for Young Investigators in Dermatology. Direct targeting of skin with DNA vaccines for genetic immunization against Leishmania in a murine model. PMID- 9366830 TI - Surgical pearl: phlebectomy hook Norplant extraction. PMID- 9366831 TI - Increasing utilization of dermatologists by managed care: an analysis of the National Ambulatory Medical Care Survey, 1990-1994. AB - Patients with managed care are less likely to see dermatologists for skin problems than are patients with traditional insurance. Through 1992, increase in the demand for treatment of skin problems reduced the effect of managed care on dermatologists. We assessed the continued impact of managed care on visits to dermatologists. Skin disease visits from the National Ambulatory Medical Care Survey were analyzed for the years 1990-1994. We found that demand for treatment of skin problems did not rise between 1992 and 1994, but demand for dermatologists services within the managed care sector more than doubled. In 1994 patients with HMO/prepaid insurance with skin disease were just as likely to see a dermatologist as were patients with commercial insurance. Mean visit duration for skin problems was 19% longer for nondermatologists than for dermatologists (p < 0.001). We conclude that dermatologists are more efficient at treating skin disease than nondermatologists and that utilization of dermatologists within managed care is increasing. PMID- 9366832 TI - Axillary granular parakeratosis: response to isotretinoin. PMID- 9366833 TI - Nail unit basal cell carcinoma: a case report and literature review. PMID- 9366834 TI - Reliability of two methods to assess morphea: skin scoring and the use of a durometer. PMID- 9366835 TI - Single patch of hair at a denervated site in a patient with alopecia universalis. PMID- 9366836 TI - Follow-up study of a patient with neurilemmomatosis. PMID- 9366837 TI - Chronic erythroderma induced by beta-blocker (timolol maleate) eyedrops. PMID- 9366838 TI - Use of eutectic mixture of local anesthetics: an effective topical anesthetic for slit-smear testing of patients with Hansen's disease. PMID- 9366839 TI - Understanding and evaluating clinical trials. PMID- 9366840 TI - Anticardiolipin antibodies in leukocytoclastic vasculitis. PMID- 9366841 TI - Localized scleroderma in breast cancer patients treated with supervoltage external beam radiation: radiation port scleroderma. PMID- 9366842 TI - Fenofibrate-induced photosensitivity: value of photopatch testing. PMID- 9366843 TI - Congenital cutaneous candidiasis associated with respiratory distress and elevation of liver function tests: a case report and review of the literature. AB - We describe congenital cutaneous candidiasis (CCC) in a term newborn. The mother had candidal vaginitis 1 week before delivery. At birth, the infant had a generalized, intensely erythematous, papulovesicular eruption, respiratory distress and elevation of liver function tests. The child responded well to intravenous amphotericin B plus topical and oral nystatin. There have been 13 previously reported cases of CCC in infants weighing more than 1500 gm who had evidence of systemic infection. Two deaths were attributed to candidal pneumonia and sepsis. The majority of infants with CCC have infection localized to the skin, but if there is any evidence of respiratory distress or signs of sepsis the possibility of systemic candidiasis and the need for parenteral antifungal therapy must be considered. PMID- 9366844 TI - Blind loop syndrome: an unusual cause of panniculitis. AB - We describe a 52-year-old woman with panniculitis and blind loop syndrome. She had undergone a gastrectomy for peptic ulcer 4 years before. Tender erythematous nodules on her palms and soles were associated with diarrhea and weight loss. A biopsy specimen revealed septal and lobular panniculitis. A glucose hydrogen breath test was consistent with bacterial overgrowth. These results were consistent with panniculitis associated with a blind loop syndrome. Only four cases of this association have been reported previously. PMID- 9366845 TI - Follicular mucinosis associated with scarring alopecia, oligoclonal T-cell receptor V beta expansion, and Staphylococcus aureus: when does follicular mucinosis become mycosis fungoides? AB - A diagnosis of alopecia mucinosa, occurring as a single scalp lesion, was made in a 40-year-old white woman who had a history of trauma. Follicular mucinosis, Staphylococcus aureus, and oligoclonal expansion of the T-cell receptor V beta chain genes 6 and 7 were present in the skin. Epidermotropic T-cell skin diseases with oligoclonal T-cell proliferations may be the result of HLA- and cytokine determined reaction patterns to persistent antigens. PMID- 9366846 TI - Subcutaneous T-cell lymphoma treated with systemic chemotherapy, autologous stem cell support, and limb amputation. AB - Subcutaneous T-cell lymphoma is an unusual variant of peripheral T-cell lymphoma in which the malignant infiltrate preferentially involves the subcutis. The disease is often initially misdiagnosed as a benign inflammatory panniculitis or a granulomatous disease. We describe subcutaneous T-cell lymphoma in a 39-year old man who was treated with systemic chemotherapy, autologous stem cell support, and amputation of the limb primarily involved with the lymphomatous infiltrate. This is the first report of amputation being included in the treatment regimen of subcutaneous T-cell lymphoma. Because preferential involvement of the extremities often occurs in patients with subcutaneous T-cell lymphoma, surgical debulking of refractory disease by partial or complete limb amputation may be a useful therapeutic adjunct. PMID- 9366847 TI - Xanthomonas maltophilia infection presenting as erythematous nodules. AB - Xanthomonas (Pseudomonas) maltophilia is increasingly being recognized as an opportunistic pathogen in hospitalized and debilitated patients. We describe X. maltophilia cellulitis in a neutropenic patient undergoing consolidation chemotherapy for acute lymphocytic leukemia. The patient had multiple, erythematous, nonulcerated nodules on the lower extremities. A biopsy specimen showed numerous gram-negative bacilli in the dermis and subcutis, without evidence of vasculitis. Tissue culture and subsequent blood cultures grew X. maltophilia. The cutaneous nodules and positive blood cultures resolved after treatment with intravenous ciprofloxacin and trimethoprim-sulfamethoxazole. PMID- 9366848 TI - Atypical lymphoid hyperplasia of the eyelids manifesting as xanthelasma-like lesions. AB - We describe a patient who had bilateral, yellow papules of the upper eyelids. This proved to be the clinical manifestation of an atypical lymphoid hyperplasia of the orbits. We describe this clinical presentation as a new sign of this condition. This finding serves to broaden the differential diagnosis of yellow papules on the eyelids. Atypical lymphoid hyperplasia of the orbits poses a challenging problem. Their benign or malignant nature cannot usually be determined by clinical and radiologic criteria. Most of these infiltrates result in extraocular lymphoma. We describe a patient with bilateral, yellow papules of the upper eyelids that proved to be a manifestation of an atypical lymphoid hyperplasia of the orbits. PMID- 9366849 TI - Identification of HHV-8 DNA in the skin lesions of Kaposi's sarcoma in an immunosuppressed patient with bullous pemphigoid. AB - Kaposi's sarcoma rarely occurs as an opportunistic tumor in iatrogenically immunosuppressed patients. We describe the clinical presentation, treatment of Kaposi's sarcoma skin lesions in an immunosuppressed patient with bullous pemphigoid. Using the polymerase chain reaction, HHV-8 DNA was detected in two separate Kaposi's sarcoma lesions but not in control tissues. The amplified DNA fragments derived from our patient's Kaposi's sarcoma skin lesions contained unique point mutations that distinguished the virus isolated from Kaposi's sarcoma lesions derived from other patients. This is the first demonstration that HHV-8 DNA is associated with Kaposi's sarcoma skin lesions in an HIV-negative, immunosuppressed patient with bullous pemphigoid. HHV-8 is probably a common latent herpesvirus that is activated by immunosuppressive therapy in genetically predisposed patients and may be involved in the pathogenesis of Kaposi's sarcoma. PMID- 9366850 TI - Target lesions on the lips: childhood herpes simplex associated with erythema multiforme mimics Stevens-Johnson syndrome. AB - Erythema multiforme and Stevens-Johnson syndrome are both characterized by areas of epithelial necrosis. An important clinical feature that distinguishes the two is the extensive mucosal necrosis in Stevens-Johnson syndrome but not in erythema multiforme. Because significant and serious complications may develop with Stevens-Johnson syndrome and not with erythema multiforme, it is important to differentiate between the conditions. We describe three boys with herpes simplex virus-associated erythema multiforme who had severe necrosis of the lips develop and were initially diagnosed with Stevens-Johnson syndrome. The lip lesions were large target lesions of erythema multiforme rather than the extensive necrosis seen in Stevens-Johnson syndrome and all three had a benign course. PMID- 9366851 TI - Therapeutic efficacy of carbamazepine in a HIV-1-positive patient with psoriatic erythroderma. PMID- 9366852 TI - Skin necrosis secondary to low-molecular weight heparin in a patient with antiphospholipid antibody syndrome. AB - Skin necrosis is a rare complication of subcutaneous heparin therapy that usually occurs at injection sites. It occasionally accompanies the heparin-associated thrombocytopenia and thrombosis syndrome. We describe a patient with the antiphospholipid syndrome who had skin necrosis develop from low-molecular weight heparin therapy at sites distant from injection sites. PMID- 9366853 TI - Herpes simplex vegetans: atypical genital herpes infection in a patient with common variable immunodeficiency. AB - Large papillomatous lesions clinically resembling verrucous carcinoma may be caused by viruses other than human papillomavirus. We report a case of recurrent vegetations covering the entire vulva in a pregnant patient with common variable immunodeficiency. Herpes simplex virus was recovered from these lesions. The patient did not respond to intravenous acyclovir, but her lesions dramatically healed with two courses of intravenous foscarnet. Repeated biopsies may prove necessary in cases such as this to ensure proper diagnoses. PMID- 9366855 TI - Mid-dermal elastolysis in an adolescent subsequent to lesions resembling granuloma annulare. AB - First described by Shelley and Wood in 1977, mid-dermal elastolysis (MDE) is a rare acquired disorder in which there is a bandlike absence of elastic tissue limited to the mid-dermis. In their patient, MDE developed in an area previously involved with recurrent episodes of urticaria. We describe a 15-year-old white girl with well-circumscribed, minimally palpable yellow-white plaques and wrinkling diagnosed histologically as MDE in areas clinically diagnosed 5 years previously as granuloma annulare. As in the first described patient, five years elapsed between clearance of the original skin lesions and the clinical appearance of MDE. To our knowledge, we report the first adolescent case of MDE localized to previous sites of lesions clinically consistent with granuloma annulare and propose that MDE represents an abnormal end-stage reaction to multiple processes. PMID- 9366854 TI - Segmental neurofibromatosis: case reports and review. AB - Segmental neurofibromatosis (neurofibromatosis type V) is a rare disorder characterized by cafe-lu-lait macules and neurofibromas, or only neurofibromas, limited to one region of the body. Three patients with segmental neurofibromatosis are described, and cases of this condition in the world literature are reviewed. Segmental neurofibromatosis has only been described in 82 patients, including our three. The median age at onset was 28 years and the incidence was higher in women (58%). The neurofibromas most commonly occupied either a cervical or thoracic dermatome and were unilateral, occurring more often on the right side (43 patients) than the left (34 patients). Cafe-au-lait macules were present in 26% of patients. Axillary freckling was described in only nine patients. Disease-associated systemic involvement was uncommon. Most patients with segmental neurofibromatosis (93%) do not have a family history of neurofibromatosis. PMID- 9366856 TI - Erythema multiforme and persistent erythema as early cutaneous manifestations of Lyme disease. AB - We report two cases of borreliosis (Lyme disease) with unusual cutaneous manifestations, erythema multiforme, and persistent erythema. The lesions in both of our patients had distinctive histopathologic features. To our knowledge, this is the first report of erythema multiforme and persistent erythema as early cutaneous manifestations of Lyme disease. PMID- 9366857 TI - Spontaneous regression of granulomatous mycosis fungoides in an HIV positive patient. AB - The development of mycosis fungoides in HIV-positive patients is uncommon. We describe the granulomatous type of mycosis fungoides in an HIV-positive patient whose cutaneous lesions regressed without treatment. In addition to HIV seropositivity and mycosis fungoides, he had a long history of pulmonary sarcoidosis. Immunophenotyping of the cutaneous lymphoid infiltrates revealed a predominance of CD4+ T cells, and monoclonality was demonstrated by T-cell gene rearrangement studies. The regression of mycosis fungoides in this patient was associated with a falling peripheral blood CD4 T-cell count. PMID- 9366858 TI - A young boy with a large hemifacial plaque with histopathologic features of trichoepithelioma. AB - Trichoepitheliomas commonly appear as sporadic solitary lesions or, more rarely, as multiple lesions that are often dominantly inherited. We describe an 8-year old boy with multiple facial papules that coalesced into a large plaque. This presentation of multiple trichoepitheliomas may represent an unusual type of nevus. PMID- 9366859 TI - Familial reticulate acropigmentation of Dohi. AB - Reticulate acropigmentation (RA) comprises dyschromic disorders that generally have an autosomal dominant pattern of inheritance, Two main forms of RA have been described: reticulate acropigmentation of Kitamura (RAK) and reticulate acropigmentation of Dohi (RAD). We observed a 21-year-old white woman who had progressive reticulate hyper- and hypopigmentation on the volar surface of her forearms and the dorsa of her hands. Many of her relatives have similar lesions. There were no pits or breaks in the epidermal ridge pattern on the palms. A biopsy specimen revealed areas with an excess of melanin in the basal layer alternating with others in which melanin was totally absent, Electron microscopic findings in a hypermelanotic area showed an increased number of melanocytes with high metabolic activity. In the hypomelanotic areas the melanocytes were morphologically abnormal with melanosomes at the early stages of development. PMID- 9366860 TI - Production of red meat should be curbed in order to conserve natural resources. PMID- 9366861 TI - Red meat production can be part of an environmentally sound future. PMID- 9366862 TI - Optimal breast-feeding duration. PMID- 9366863 TI - The role of nutrition support dietitians as viewed by chief clinical and nutrition support dietitians: implications for training. AB - OBJECTIVES: To determine current and ideal frequencies with which nutrition support dietitians perform each item on a list of 15 tasks and evaluate dietitian preparation for the practice of nutrition support. DESIGN: Data were collected using two questionnaires, one completed by the chief clinical dietitian and the other completed by the nutrition support dietitian at each hospital surveyed. Both versions of the questionnaires contained a list of 15 tasks that had been validated as being related to advanced nutrition support by a panel of 20 nutrition support experts using a modified Delphi method. Follow-up telephone calls were made to increase the number of responses. SAMPLE: Questionnaires were mailed to the chief clinical dietitian at 300 randomly selected, general medical/surgical hospitals with 300 or more beds in the United States and Puerto Rico. A total of 134 chief clinical dietitians (45%) and 129 nutrition support dietitians (43%) responded to the surveys; 124 (41%) and 120 (40%) questionnaires, respectively, were usable for statistical analyses. STATISTICAL ANALYSES: The Wilcoxon matched-pairs signed-ranks test was used to determine differences between nutrition support dietitian actual and ideal frequencies and between chief clinical dietitian actual and ideal frequencies for each of the 15 tasks. The Mann-Whitney U-Wilcoxon rank sum W test was used to determine differences between nutrition support dietitian and chief clinical dietitian actual frequencies and between nutrition support dietitian and chief clinical dietitian ideal frequencies for each of the 15 tasks. Descriptive statistics were used to analyze the questions regarding educational preparation for nutrition support practice and demographic data. RESULTS: The ideal frequency for each of the 15 tasks was significantly greater (P < .0001) than the actual frequency reported by nutrition support dietitians and chief clinical dietitians. Whereas chief clinical dietitians and nutrition support dietitians agreed on the ideal frequency for most tasks, the nutrition support dietitian ideal frequency indicated for the tasks "determines macronutrient composition of parenteral nutrition" and "performs physical examinations related to nutritional status, fluid status, and gastrointestinal function" was significantly greater (P < .001, P < .05), respectively) than the ideal frequency indicated by chief clinical dietitians. Of the nutrition support dietitians, 79% agreed and 16% somewhat agreed that experiences beyond those required for becoming a registered dietitian are needed to provide nutrition support dietitians with specialized clinical skills. APPLICATIONS/CONCLUSIONS: Nutrition support dietitians desire increased responsibility for delivering nutrition support to their patients and this desire is largely supported by chief clinical dietitians. Nutrition support dietitians appear to have a strong interest in postregistration qualifying experiences that would provide a foundation for expanding their roles. According to the results of this study, programs designed to provide practical, clinical experience in nutrition support are needed. PMID- 9366864 TI - Predictors of poor maternal weight gain from baseline anthropometric, psychosocial, and demographic information in a Hispanic population. AB - OBJECTIVE: To identify which baseline factors best predict poor maternal weight gain among Hispanics. SAMPLE: Pregnancy and outcome data collected prospectively from 4,791 Hispanic women attending public prenatal clinics in West Los Angeles, Calif, from 1983 through 1986. METHODS: Prepregnancy weight was categorized into weight status groups using body mass index (BMI). Poor total weight gain (based on a mean gestational age at last measurement, which was at 35 weeks) was defined as less than 21 lb for women with BMI less than 26 and less than 10 lb for women with BMI of 26 or greater. Analyses used Student's t test, chi 2, and multivariate regression techniques (linear and logistic). RESULTS: Poor total weight gain was identified in 29% of the women. For women who were underweight or normal weight before pregnancy, the only factor associated with increasing the risk of poor total weight gain was short stature (adjusted odds ratio [AOR] = 1.5, 95% confidence interval [CI] = 1.24, 1.84). The following factors decreased the risk: being US born (AOR = 0.61, 95% CI = 0.37, 1.00); being primiparous and under 29 years old (for < 20 years AOR = 0.69, 95% CI = 0.51, 0.92 and for 20 to 29 years AOR = 0.63, 95% CI = 0.49, 0.81); planning the pregnancy (AOR = 0.82, 95% CI = 0.67, 1.00); and having a close relative die during the pregnancy (AOR = 0.65, 95% CI = 0.44, 0.95). For obese and overweight women, physical abuse by the baby's father increased the risk (AOR = 3.19, 95% CI = 1.27, 8.01) of poor total weight gain, whereas receiving financial support from the baby's father decreased the risk (AOR = 0.59, 95% CI = 0.37, 0.95). APPLICATIONS/CONCLUSIONS: These baseline factors could aid in targeting nutrition and other social services earlier to pregnant Hispanic women. By strategically targeting pregnant women in greatest need of services, improvements in birth outcomes may be enhanced. PMID- 9366865 TI - Plasma and erythrocyte zinc concentrations and their relationship to dietary zinc intake and zinc supplementation during pregnancy in low-income African-American women. AB - OBJECTIVE: To evaluate the effects of usual dietary intake of zinc and of zinc supplementation during pregnancy on plasma and erythrocyte zinc concentrations. DESIGN: A randomized, double-blind, placebo-controlled trial. SUBJECTS: Low income African-American women (n = 580) assigned randomly to groups at 19 weeks of gestation. INTERVENTION: A daily dose of zinc (25 mg) or a placebo until delivery. MAIN OUTCOME MEASURES: Plasma, erythrocyte, and dietary zinc levels. STATISTICAL ANALYSES: Multiple regression and repeated measures analysis of variance. RESULTS: In both the placebo and the supplemented groups, when all subjects were grouped by usual dietary zinc intake above or below the median (12 mg/day), results were the same: Women with high dietary zinc intake had higher erythrocyte zinc levels at the time of randomization and at all subsequent measurements during pregnancy than those who had low dietary zinc intake (P < or = .06; difference not significant for zinc-supplemented group); no difference was observed for plasma zinc levels. On the other hand, when the subjects were stratified at the median by total daily zinc intake (usual dietary zinc + 25 mg zinc supplement) during pregnancy, a significant difference in plasma zinc levels (P < .005) was found between women with high total zinc intake (mean = 38 mg/day) and low total intake (mean = 13 mg/day) at 26, 32, and 38 weeks of gestation; however, no such differences were found in erythrocyte zinc levels. APPLICATIONS: These results should help dietitians and other health professionals better understand the expected changes in plasma and erythrocyte zinc levels during pregnancy, and the relationship between dietary and supplemental zinc and zinc nutriture. PMID- 9366866 TI - Food acquisition habits, nutrient intakes, and anthropometric data of Havasupai adults. AB - OBJECTIVE: To describe the dietary patterns, anthropometric data, and food sources of Havasupai adults (> or = 18 years old) and determine the effect of age and gender. DESIGN: Dietary intakes (one 24-hour recall), anthropometric measures (body mass index [BMI], waist-to-hip ratio [WHR]) and demographic data, including sites of food purchases, were obtained. Food sources of selected nutrients were calculated from diet recalls. SETTING/SUBJECTS: 92 adults (60 women, 32 men) from the Havasupai Reservation, Supai, Ariz. STATISTICAL ANALYSES: Descriptive statistics were generated for demographic data. Nutrient intakes, BMI, and WHR were compared across gender and age groups ("Younger" [18 to 59 years old] vs "older" [> or = 60 years old]) by one-way analysis of variance. Two-tailed t tests identified significant differences in selected food practices by age group. RESULTS: Diets were moderately high in fat (35% of energy), saturated fat (12%), and sugar (14%); intakes of zinc, calcium, vitamin A, vitamin B-6, and folate were frequently inadequate (less than two thirds of the Recommended Dietary Allowance). Of the 92 subjects, 76 (83%) were obese (BMI > or = 27). Fifty-four of the 60 women (90%) and 24 of the 32 men (75%) exhibited abdominal obesity (no age effect). Thirty-nine of the subjects (42%) consumed at least one food item purchased off the reservation on the day of the recall; the remaining 53 subjects (58%) consumed only food purchased or acquired on the reservation. Older Havasupai were significantly more dependent on the tribal store and other village food sources than were younger adults. Food sources of key nutrients did not differ by age or gender. APPLICATIONS: The dietary patterns of isolated populations may be shaped by the unique limitations of their food sources as well as by factors such as age and gender. Individual and community-wide efforts to improve nutrient intakes and food patterns must recognize these geographic limitations. For populations such as the Havasupai, cooperative marketing and health promotion efforts between tribal officials, health care providers, and managers of the cafe and tribal store could improve the availability and consumption of a wider range of health-promoting foods. PMID- 9366867 TI - Resting energy expenditures in Asian women measured by indirect calorimetry are lower than expenditures calculated from prediction equations. AB - OBJECTIVE: Measured resting energy expenditure (REE) and REEs calculated using the Harris-Benedict equation, Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU) equations (FAO equations), and the Liu equation were compared in Asian women. DESIGN: REEs were measured using indirect calorimetry in the morning after an overnight fast and compared with REEs calculated using the Harris-Benedict equation, the FAO equations, and the Liu equation. Height, weight, and 3-day diet records were also obtained. SUBJECTS: Thirty-six healthy, free-living Asian women aged 19 to 52 years and living in the United States were recruited from Washington State University, Pullman, and completed the study. STATISTICAL ANALYSES: Paired t tests, stepwise regression, one-way analysis of variance, and Pearson correlation coefficients were used for the statistical analyses. Significance was set at P < or = .05. RESULTS: A significant correlation was found between measured REE and REE derived from the Harris-Benedict equation (R = 0.67, P < .0001), the FAO equations (R = 0.70, P < .0001), and the Liu equation (R = 0.70, P < .0001). However, measured REE was significantly lower than REE calculated using the Harris-Benedict and FAO equations by 8.5% (P < .001) and 5.4% (P < .01), respectively. No significant difference was noted between measured REE and REE derived from the Liu equation. APPLICATIONS: Caution must be taken when predicting REE of Asian women using the Harris-Benedict equation or the FAO equation. Indirect calorimetry or an equation specific to Asians, such as the Liu equation, is recommended when an accurate estimate is necessary. PMID- 9366868 TI - Impact of gender, ethnicity, meal component, and time interval between eating and reporting on accuracy of fourth-graders' self-reports of school lunch. AB - OBJECTIVE: To validate fourth-graders' self-reports of school lunch by comparing their reports to lunch observations, and to determine the impact on accuracy of gender, ethnicity, meal component, and time interval between eating and reporting. DESIGN: Students were randomly selected, observed eating lunch, and interviewed the same day, next day, or Monday regarding Friday's lunch. Accuracy of reporting items was determined by tallying matched foods (items reported and observed), phantom foods (items reported but not observed), and omitted foods (items not reported but observed). Accuracy of reporting amount eaten was determined by calculating absolute and arithmetic differences. SUBJECTS: Subjects were 260 students: 89 same-day, 148 next-day, and 23 Monday recalls; 59 whites (30 boys) and 201 blacks (103 boys) from four schools. STATISTICAL ANALYSES: Rates for matched, phantom, and omitted foods; analysis of variance; Friedman's nonparametric analog of analysis of variance; Student-Newman-Keuls' post hoc comparisons. RESULTS: In regard to reporting items, the respective rates for matched, phantom, and omitted foods were 84%, 5%, and 16% for same-day recalls; 68%, 13%, and 32% for next-day recalls; and 38%, 48%, and 62% for Monday recalls. Rates for omitted and phantom foods were higher for Monday recalls than for next day recalls, which were higher than for same-day recalls (P < .05 for all). In regard to reporting amounts, analysis by gender, ethnicity, and time interval failed to yield significant main or interaction effects. When children correctly reported items eaten, they were quite accurate in reporting amounts eaten. Omitted food rates were lowest for beverage, followed by entree, and highest for miscellaneous and condiment. APPLICATIONS: Even under the best conditions (ie, reporting within 90 minutes after eating school lunch), children have difficulty accurately reporting what they have eaten. As the time interval between eating and reporting increases, accuracy decreases markedly. Techniques that improve reporting of items eaten should result in improved accuracy of reporting amounts eaten. PMID- 9366869 TI - Final regulations for the nutrition labeling of raw fruits, vegetables, and fish. AB - In August 1996, the US Food and Drug Administration published regulations that revised the guidelines for voluntary nutrition labeling of raw fruits, vegetables, and fish; revised the criteria for retailers' compliance with the guidelines; and updated the nutrition labeling values for the 20 most frequently consumed raw fruits, vegetables, and fish. These actions were in response to the requirements of the Nutrition Labeling and Education Act of 1990 and make the voluntary nutrition labeling program more consistent with mandatory nutrition labeling of other foods. The provisions of the final rule are important for dietitians who develop nutrition education materials for retail stores and for dietitians who instruct patients and clients in selecting foods according to nutrition labeling information. PMID- 9366870 TI - Physicians prefer goal-oriented note format more than three to one over other outcome-focused documentation. AB - To assess preference for outcome-focused nutrition notes, two note formats were selected from the literature and tested against a modified, goal-oriented format. Focus charting and intervention, evaluation, and revision (IER) formats were compared with a charting-by-exception style that was modified to include goals and reassessment of risk. Notes were handwritten in each format and contained the same information. Physicians were asked to choose their preference and explain why that format was selected. Initially, focus charting was tested against the goal-oriented format. The more popular of the two was then tested against the IER format. Nineteen physicians were surveyed by a registered dietitian for each comparison. Physicians preferred the goal-oriented format over focus charting and IER formats 9:1 and 3:1, respectively. In the first survey, physicians preferred the goal-oriented format because the plan was clearly stated, thereby rendering the note easier to understand. The goal-oriented format was preferred in the second survey because the note was considered to be concise and easy to read and contained expected outcomes. Physicians want short communication that includes easily identifiable goals and plans. We recommend that experienced dietitians use the goal-oriented format developed for this study, and preferred by physicians, for follow-up nutrition notes. PMID- 9366871 TI - Impact of expectant fathers in breast-feeding decisions. PMID- 9366872 TI - Health practitioners should consider parity when counseling mothers on decisions about infant feeding methods. PMID- 9366873 TI - Position of the American Dietetic Association: vegetarian diets. PMID- 9366874 TI - Outcome measures and care delivery systems. Introduction and purposes of conference. PMID- 9366875 TI - Studying outcomes of organizational change in health services. AB - OBJECTIVES: The rapidly changing organizational context within which health care is delivered is altering provider-patient relations and processes of clinical decision-making, with significant implications for patient outcomes. Yet definitive research on such effects is lacking. The authors seek to underscore the contribution of organizational research to studies of clinical outcomes and demonstrates several approaches to further such efforts. METHODS: The authors present a theoretical framework of the operant mechanisms linking organizational attributes and patient outcomes. They use case examples from their ongoing research on hospitals to illustrate strategies for measuring these mechanisms and for overcoming some of the feasibility issues inherent in organizational research. RESULTS: Several methodological issues are explored: (1) exploiting "targets of opportunity" and "natural experiments" is a promising strategy for studying patient outcomes related to organizational reform; (2) indices of organizational traits, constructed from individual survey responses, can illuminate the operant mechanisms by which structure affects outcomes; and (3) secondary data sources and innovative statistical matching procedures provide a feasible strategy for constructing study comparison groups. Extending the organizational outcomes research strategy to new areas of inquiry offers an opportunity to enhance our understanding of how nursing organization affects outcomes. CONCLUSIONS: Improving the effectiveness of medical care in a health care system undergoing fundamental restructuring requires greater understanding of how organizational context affects clinical outcomes. A higher priority should be placed on organizational outcomes research by researchers and funding agencies. PMID- 9366876 TI - Adverse outcomes and variations in organization of care delivery. AB - OBJECTIVES: This article evaluates the state of the science with respect to morbidity, mortality, and adverse effects as outcomes indicative of variations in organizational variables in care delivery systems. METHODS: Eighty-one research papers research examining relations among organizational structures or processes and mortality/adverse effects were reviewed, assembled from electronic and manual searches of the biomedical and health services research literature. RESULTS: Most research relating mortality and other adverse outcomes to organizational variables has been conducted in acute care hospitals since 1990, with these outcome indicators linked more frequently to organizational structures than to organizational or clinical processes. There is support in some studies, but not in others, that nursing surveillance, quality of working environment, and quality of interaction with other professionals distinguish hospitals with lower mortality and complications from those with higher rates of these adverse effects. Increasing sophistication of risk adjustment methods suggests that variations in mortality and complications are influenced by patient variables more than by organizational variables. Adverse events may be a more sensitive marker of differences in organizational quality in acute care hospitals and long term care. CONCLUSIONS: Taken together, the acute care studies are not conclusive regarding the extent to which the organizational features of care delivery systems positively influence such bottom-line outcomes as mortality. As severity adjustment methods become more refined for hospital patients, many of the small differences currently seen in mortality and complications may disappear. However, given that adverse events appear more closely related to organizational factors than in mortality, researchers need to refine and better define such events that are logically related to the coordinative organizational processes among caregivers. Finally, researchers need to go much beyond mortality, morbidity, and adverse events in evaluating the linkage between the organization of care and outcomes. PMID- 9366877 TI - Achievement of appropriate self-care. Does care delivery system make a difference? AB - OBJECTIVES: The purpose of this article is to review the evidence linking variations in care delivery system with achievement of appropriate self-care. METHODS: This synthetic review of the research literature used the Outcomes Model for Health Care Research. The concept of self-care was reviewed from several theoretical perspectives, as was the quality of instruments used to measure aspects of self-care. Finally, studies examining the linkage between care delivery system and self-care were critically analyzed. RESULTS: Reliable and valid instruments exist to measure self-care agency and self-care performance, and these data elements are collected routinely in many care settings. Only a few studies, however, have examined the relation between achievement of self-care and variations in delivery systems. CONCLUSIONS: Achievement of appropriate self-care may be an outcome measure better suited to nonacute care settings or across the continuum of care. Additionally, work is needed in applying risk-adjustment strategies to the measurement of achievement of appropriate self-care. PMID- 9366878 TI - Health-related quality of life as an outcome in organizational research. AB - This article discusses the conceptual and methodological issues that continue to plague health-related quality of life (HRQOL) research. The current conceptualizations of the construct are reviewed to make explicit the issues of diversity and lack of consensus in definitions, validity of the conceptual unity of multiple domains, and lack of attention to the integration of the HRQOL construct into a theoretical meaningful model. Inadequately addressed conceptual issues have resulted in the proliferation of scales to measure HRQOL the measurement issues to a need to focus on precision and sensitivity of measures. The author offers a new conceptualization of HRQOL, which encompasses both health care provider and patient perspectives. PMID- 9366879 TI - Finding health-related quality of life outcomes sensitive to health-care organization and delivery. AB - OBJECTIVES: The author identifies and assesses health-related quality-of-life outcomes for evaluating health-care structure and process. METHODS: Development of a conceptual model and presentation of case studies are used to identify methods of outcomes research necessary to evaluate health-care organization and delivery. RESULTS: Generic measures already exist for assessing functional status and well-being outcomes of health care. Condition-specific measures are necessary to address directly the concerns of patients and providers of care and to detect small differences in organizational arrangements. Improved health outcomes are more likely to be observed from large-scale prospective trials and studies using large data sets, but few studies report improved self-reported health status as linked to organizational structure. CONCLUSIONS: Theoretically driven research is necessary to link healthcare systems and outcomes. Outcome measures exist, but measurement development is needed for organizational arrangements, managed care structure and process, and stakeholder exchanges. PMID- 9366880 TI - The use of patient perceptions in the evaluation of health-care delivery systems. AB - OBJECTIVES: Patient perceptions are increasingly used to measure quality of care in a diversity of health-care delivery settings. The goals of this article are to review the current use of patient perceptions and to review what is known about the sensitivity of patient perceptions for discerning variations in care across delivery systems. METHODS: This article first provides a rationale for using patient perceptions to evaluate delivery systems and reviews proposed frameworks for measuring perceptions. It then reviews illustrative studies that have used patient perceptions to compare delivery systems or that have examined associations between patient perceptions and other health-care indicators. RESULTS: Although the results of these studies suggest some general relations between patient perceptions and characteristics of delivery systems, findings are often inconsistent across individual studies. These inconsistencies may be related to several potential methodological limitations, including failure to account for the impact of patient mix, ceiling effects of patient responses, nonresponse bias, differences in data collection methods and timing of surveys, use of proxy respondents, and differences in survey instruments. CONCLUSIONS: The discussion concludes with five conceptual challenges and recommendations for further research: (1) to establish the sensitivity of patient perceptions for discerning differences across delivery systems; (2) to establish relations between alternative frameworks for measuring patient perceptions; (3) to standardize the measurement of patient perceptions; (4) to define optimal ways of presenting patient perceptions data to users; and (5) to broaden the "patient" populations in which perceptions of care have been measured. PMID- 9366881 TI - Symptom management outcomes. Do they reflect variations in care delivery systems? AB - OBJECTIVES: Symptom management is increasingly recognized as a critical element of patient care, particularly in managing chronic illness. However, research on outcomes related to symptom management is in its infancy, except for the symptom of pain. This symptom was therefore chosen as a prototype to review the state of the science regarding relations between organizational variables and symptom management outcomes and to illustrate the issues regardless of the symptom managed. This article discusses pain outcome measures appropriate for acute and cancer pain, proposes attributes of the care delivery system that may affect outcome measures, and identifies challenges associated with this type of research. METHODS: Review of quality assurance studies raises issues concerning the adequacy of currently used outcomes for pain and satisfaction with pain management. Although considerable effort has been expended in developing pain measurement in adults and children, critical issues for examining pain management outcomes include deciding what perspectives should be used as the most valid indicator of the pain outcome and when the measures should be obtained. RESULTS: Critical concerns are raised about the measure of satisfaction with pain management and its appropriateness as the end-result outcome. A key issue is whether respondents actually disentangle satisfaction with pain management from satisfaction with other aspects of care, including caring dispositions of health care providers. Finally, the question is raised: Are pain outcomes affected by organizational context? CONCLUSIONS: Although the answer to this question is unknown, a few research studies suggest that organizational context is likely to influence pain outcomes. It is clear, however, from ongoing work that until several conceptual, methodological, and analytic challenges are resolved, research is unlikely to capture the influence of variations in care delivery systems on symptom management outcomes. PMID- 9366882 TI - Data, information, and knowledge. Theoretical and methodological issues in linking outcomes and organizational variables: introduction. PMID- 9366883 TI - Methodological issues linking costs and outcomes. AB - OBJECTIVES: The author examined issues in linking costs and outcomes in care delivery systems research. METHODS: Literature regarding cost analyses and outcomes is discussed in light of the following methodological issues: what costs can be captured, how costs should be allocated, whose costs are being considered in relation to the choice of meaningful outcomes measures, and what magnitude of intervention is required to achieve the outcomes. RESULTS: Although various methods are used to estimate the costs of providing health care, direct determination of cost is elusive, and measurement problems limit comparison across studies and institutions. Further, the linkage among outcomes, organizational variables, and the "intervention dose" needed to produce the desired outcomes is not well developed. CONCLUSIONS: The methodological issues linking costs and outcomes pose challenging research opportunities: the choice of the most feasible measures for estimating costs of care across sites of care delivery, the examination of shifts in cost burden, the most meaningful measures of outcomes as relevant to different stakeholders, the magnitude of intervention needed to produce a change in outcome, and the cost of achieving that change. PMID- 9366884 TI - Methodological issues in linking costs and health outcomes in research on differing care delivery systems. AB - OBJECTIVES: This article discusses, from an economist's point of view, issues in designing and conducting research including cost and outcomes variables among differing care delivery systems. METHODS: Issues were identified, and selected research purporting to link cost and outcomes with variations in care delivery systems was reviewed. RESULTS: Current literature on nursing care delivery systems and costs in hospitals, ambulatory care, and nursing homes is focused mainly on group-specific costs linked to patient-specific outcomes. It suffers further from focusing primarily on single-discipline components of care, omitting the contributions of other providers beyond nursing personnel. CONCLUSIONS: Multidisciplinary teams, including economists who can speak clinical language, are recommended. PMID- 9366885 TI - Outcomes across the care continuum. AB - OBJECTIVES: This article focuses on issues facing scientists and clinicians in developing outcomes useful across the care continuum, particularly in examining the impact of care delivery systems. METHODS: Research and current corporate examples of the continuum of care delivery and relevant outcomes were reviewed. Questions addressed included the following: How do we know when networks or care systems are successful? What are the clinical and financial indicators of system success? What are the indicators of declining performance? RESULTS AND CONCLUSIONS: Approaches to describing program or system outcomes have included snapshots at single points in time, snapshots of system transitions, multiple snapshots (global indicators), and population-based outcomes. Crucial methodological issues include identification of severity and risk adjustment, access to usable data across settings, determination of the portion of an intervention to allocate to quality and cost outcomes, and integration of disease specific, population-specific, and general outcome measures. PMID- 9366886 TI - Outcomes across the care continuum. Home health care. AB - OBJECTIVES: This article describes one approach to measuring outcomes across the continuum of care. METHODS: Development and testing of the outcome-based quality improvement methodology as developed by the University of Colorado Center for Health Services Research in Denver, Colorado are summarized. RESULTS: Reliable and valid measures for home health care covering end results (pure outcome), intermediate results (instrumental outcome), and use (proxy outcome) were developed and are useful in demonstrating patient improvement or stabilization as well as decline. Further, these measures can be aggregated by agency and, with appropriate severity or risk adjustment, can be used to compare outcomes over time and across agencies. CONCLUSIONS: National testing of the methodology is currently ongoing, with refinements underway in measures, risk adjustment, and operational implementation. PMID- 9366887 TI - Measurement into practice. Summary and recommendations. PMID- 9366889 TI - Modeling valuations for EuroQol health states. AB - OBJECTIVES: It has become increasingly common for preference-based measures of health-related quality of life to be used in the evaluation of different health care interventions. For one such measure, The EuroQol, designed to be used for these purposes, it was necessary to derive a single index value for each of the 243 health states it generates. The problem was that it was virtually impossible to generate direct valuations for all of these states, and thus it was necessary to find a procedure that allows the valuations of all EuroQol states to be interpolated from direct valuations on a subset of these. METHODS: In a recent study, direct valuations were elicited for 42 EuroQol health states (using the time trade-off method) from a representative sample of the UK population. This article reports on the methodology that was adopted to build up a "tariff" of EuroQol values from this data. RESULTS: A parsimonious model that fits the data well was defined as one in which valuations were explained in terms of the level of severity associated with each dimension, an intercept associated with any move away from full health, and a term that picked up whether any dimension in the state was at its most severe level. CONCLUSIONS: The model presented in this article appears to predict the values of the states for which there are direct observations and, thus, can be used to interpolate values for the states for which no direct observations exist. PMID- 9366888 TI - Quantitative methods in research on complementary and alternative medicine. A methodological manifesto. NIH Office of Alternative Medicine. AB - OBJECTIVES: This article summarizes the deliberations of the Quantitative Methods Working Group convened by the National Institutes of Health (NIH) in support of the NIH Office of Alternative Medicine. METHODS: The working group was charged with identifying methods of study design and data analysis that can be applied to empirical research on complementary and alternative medicine. This charge was broad and inclusive and addressed the evaluation of alternative therapies, the investigation of the basic science of complementary medical systems, studies of health promotion and disease prevention, and health services research. RESULTS: The working group produced a "methodological manifesto," a summary list of seven recommended methodological guidelines for research on alternative medicine. These recommendations emphasize the robustness of existing research methods and analytic procedures despite the substantive unconventionality of alternative medicine. CONCLUSIONS: Contrary to the assertions of many researchers and alternative practitioners, established methodologies (eg, experimental trials, observational epidemiology, social survey research) and data-analytic procedures (eg, analysis of variance, logistic regression, multivariate modeling techniques) are quite satisfactory for addressing the majority of study questions related to alternative medicine, from clinical research on therapeutic efficacy to basic science research on mechanisms of pathogenesis and recovery. PMID- 9366890 TI - Evaluation of index and profile measures of health status in a randomized controlled trial. Comparison of the Medical Outcomes Study 36-Item Short Form Health Survey, EuroQol, and disease specific measures. AB - OBJECTIVES: The authors compare two generic measures of health status with disease-specific measures in a randomized controlled trial of transurethral resection of the prostate with laser vaporization prostatectomy for benign prostatic hypertrophy. METHODS: Patients entered into the trial completed the following questionnaires prior to treatment and at follow-up at 3 months and 1 year. The Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) is a generic measure that produces an eight-dimension profile as well as two summary measures of health status (the physical component score and the mental component score). The EuroQol provides two single index measures of health status; one intended to convey the utility (or lack of) that an individual derives from his or her own health state compared with alternative states and a second simple visual analog scale "thermometer" of health status. The American Urological Association symptom score and the Bothersome index are disease-specific indices of health status for use specifically with benign prostatic hypertrophy patients. RESULTS: The EuroQol indicates no statistically significant improvements with time for either arm of the trial. The SF-36 physical and general health perceptions domains indicates statistically significant improvements for the transurethral resection of the prostate arm alone at 3 months and 1 year, as do the physical summary score at the 3-month follow-up visit. The effect sizes of these improvements, however, are small, using standard criteria. In contrast, statistically significant differences are found with time for both transurethral resection of the prostate and laser prostatectomy on both disease-specific measures, which also indicate statistically significant superior outcome for the transurethral resection of the prostate arm compared with the laser arm. CONCLUSIONS: The results indicate that the disease-specific measures are more sensitive to change than the generic measures of outcome. Possible explanations for this are discussed. PMID- 9366891 TI - The effect of increased prescription drug cost-sharing on medical care utilization and expenses of elderly health maintenance organization members. AB - OBJECTIVES: The nature and extent of prescription drug benefits for the elderly are a continuing concern for health-care managers and policy makers. This study examined the impact of increased prescription drug cost-sharing on the drug and medical care utilization and expenses of the elderly. METHODS: Two groups of well insured Medicare risk-based members of a large health maintenance organization (HMO) had their copayments increased in different years during a 3-year period. Four 2-year analysis periods were established for comparing these elderly groups. During one analysis period, copayments did not change in either group. RESULTS: Moderate increases of from $1 to $3, from $3 to $5 per copayment, and from 50% per dispensing to 70% per dispensing with a maximum payment per dispensing resulted in lower annual per capita prescription drug use and expenses. No consistent annual changes were observed in either medical care utilization (office visits, emergency room visits, home health-care visits, hospitalizations) or total medical care expenses across analysis periods. CONCLUSIONS: No consistent relationships were observed between increased copayments per dispensing and medical care utilization and expense. Future research needs to address the impact on the classes of medications received and related health status, and the impact of larger increases in copayments per dispensing on medical care and health-related factors. PMID- 9366892 TI - The prevalence and consequences of unmet need. Contrasts between older and younger adults with disability. AB - OBJECTIVES: This article investigates the prevalence, determinants, and consequences of unmet need for assistance with activities of daily living (ADLs), instrumental activities of daily living (IADLs), and transportation in a randomly selected sample of adults with disability residing in Springfield, Massachusetts. METHODS: Respondents were contacted through random digit dialing, and eligibility was determined through a disability screen. Eligible individuals were stratified by age; 632 people were interviewed (78% of contacted eligibles). The prevalence of need and unmet need for ADLs, IADLs, and transportation assistance was calculated separately by age strata, as was the prevalence of selected negative consequences attributed to inadequate help with specific activities. The determinants of unmet need were modeled using logistic regression. RESULTS: The prevalence of unmet need for assistance with individual ADLs ranged from 4.1% (eating) to 22.6% (transferring) of the full sample. Unmet need for IADLs assistance was higher, ranging from 15.9% (cooking) to 34.6% (heavy housekeeping). Respondents younger than age 65 reported higher levels of unmet need for IADLs and transportation help than respondents age 65 or older; members of the younger group also were more likely to report five of the seven negative consequences attributed to inadequate help with IADLs and transportation (eg, missing medical appointments). Regression results revealed inability to meet expenses, having few or no reliable helpers, and impairment severity to be key determinants of unmet need. CONCLUSIONS: Financial problems, and not age per se, placed working age adults at elevated risk of unmet need in this study. The consequences of inadequate help can impede management of chronic health conditions, and may compromise individuals' ability to maintain a safe and reasonable quality of community living. PMID- 9366894 TI - Interactional synchrony, positivity, and patient satisfaction in the physician patient relationship. PMID- 9366893 TI - A preventive services demonstration. Health status, health behaviors, and cost outcomes 2 years after intervention. The Johns Hopkins Medicare Preventive Services Demonstration Team. PMID- 9366895 TI - Assessing compliance to antihypertensive medications using computer-based pharmacy records. AB - Systematic approaches for compliance problem detection and intervention are needed if the benefits of prescribed drug therapy in chronic disease management are to be optimized. As with all measures of compliance, computer algorithms based on refill patterns have advantages and disadvantages. They are unobtrusive and easily determined, but they measure the timeliness of prescription refills, not actual drug-taking. Computer-generated algorithms for assessing compliance based on refill patterns should be used by practitioners with caution, because they are not only markers for potential drug taking compliance problems, but also for discrepancies between the medical chart, pharmacy records and verbal advice given to the patient. Because patients may obtain refills before depleting their supply, compliance rates using this methodology are best determined across several refills. In particular, we urge caution in applying them over time periods of less than 60 days. Longer minimum time periods further decrease the likelihood of "false positives" but limit the number of patients for whom a compliance measure can be computed. For the health professional (eg, the pharmacist) responsible for monitoring drug-taking compliance of patients, the message seems clear: when reviewing computer-generated noncompliance "flags," the first task is to fully explore the possibility of discrepancies in drug records before initiating compliance-related interventions. PMID- 9366896 TI - Apoptosis in HL-60 cells induced by 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H] furanone (MX). AB - The potent bacterial mutagen 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-furanone (MX), which is formed during chlorination of drinking water, has been studied with respect to induction of cell death in promyelocytic leukemic HL-60 cells. Cells exposed to MX for 1 h and further incubated for 3 h, revealed no significant increase in the proportion of cells with compromised plasma membrane damage as judged by trypan blue or propidium iodide exclusion. However, flow cytometric studies and microscopic analysis of HL-60 cells after staining with Giemsa or Hoechst 33342, revealed that more than 30% of the cells exposed to 30 100 microM of MX, showed the characteristic morphology and biochemical markers of apoptosis. On the other hand, in cultures exposed to 300 microM MX, less than 5% of the cells appeared to be apoptotic (< G1 DNA) 3 h after treatment, which is similar to control values. Microscopic analysis of Hoechst 33342-stained cells revealed that they were 'arrested' in the early stages of chromatin condensation, but these cells eventually became necrotic. Some decrease in the percentage of cells in S-phase was observed 3 h after exposure to MX (10, 30 and 100 microM), but the induced cell death was not markedly cell stage specific. The characteristic ladder pattern of apoptotic cells was observed when DNA isolated from MX-exposed HL-60 cells was electrophoresed in agarose. The apoptotic process could also be detected by analysis with alkaline filter elution (AE), as a decrease in the total DNA recovered; and by single cell gel electrophoresis, as a decrease in the average number of cells/comets observable on each slide. With the protocols used no apparent increase in values in the normalized area above the curve (NAAC) (alkaline elution) or tail moments (single cell gel electrophoresis (SCGE)) were detected, indicating that apoptotic cells are not necessarily a confounding factor when assaying for genotoxicity with these techniques. PMID- 9366897 TI - Dose-dependent binding of trichloroethylene to hepatic DNA and protein at low doses in mice. AB - Trichloroethylene (TCE) is a widely used industrial chemical and a low level contaminant of surface and ground water in industrialized areas. It is weakly mutagenic in several test systems and carcinogenic in rodents. However, the mechanism for its carcinogenicity is not known. We investigated the binding of [1,2-14C]TCE ([14C]TCE) to liver DNA and proteins in male B6C3F1 mice at doses more relevant to humans than used previously. The time course for the binding was studied in animals dosed with 4.1 micrograms [14C]TCE/kg body weight (b.w.) and sacrificed between 0.5 and 120 h after i.p. injection. A dose response study was carried out in mice given [14C]TCE at doses between 2 micrograms/kg and 200 mg/kg b.w. and sacrificed 2 h post-treatment. [14C]TCE associated with the DNA and protein extracts was measured using accelerator mass spectrometry. The highest level of protein binding (2.4 ng/g protein) was observed 1 h after the treatment followed by a rapid decline, indicating pronounced instability of the adducts and/or rapid turnover of liver proteins. DNA binding was biphasic with the first peak (75 pg/g DNA) at 4 h. However, the highest binding (120 pg/g DNA) was found between 24 and 72 h after the treatment. Dose response curves were linear for both protein and DNA binding. The binding of TCE metabolites to DNA was ca. 100 fold lower than to proteins when calculated per unit weight of macromolecules and when measured 2 h post-exposure. This study shows that TCE metabolites bind to DNA and proteins in a dose-dependent manner in liver, one of the target organs for its tumorigenicity. Thus, protein and DNA adduct formation should be considered as a factor in the tumorigenesis of TCE. PMID- 9366898 TI - Carcinogenecity of the N-acyl derivatives of N-hydroxy-trans-4-aminostilbene in CD rats. AB - Carcinogenicities of the N-formyl (N-OH-FAS), N-acetyl (N-OH-AAS) and N-propionyl (N-OH-PAS) derivatives of N-hydroxy-trans-4-aminostilbene (N-OH-AS) were investigated in male and female CD rats. They were injected, i.p. 10 mumol/kg body weight (bwt) twice a week for 6 weeks, and they were killed at the end of 62 weeks. The N-formyl, N-acetyl and N-propionyl derivatives of N-hydroxy-4 aminobiphenyl (N-OH-ABP) were similarly injected at a dose of 100 mumol/kg bwt for comparison in female CD rats. Tumors of the liver, mammary gland and ear duct were produced in the female rats by these N-OH-AS derivatives. N-OH-AAS and N-OH PAS were more active in the induction of mammary and ear duct tumors than N-OH FAS. These N-OH-AS derivatives produced more tumors than did the N-OH-ABP derivatives, even at 1/10 dose of the N-OH-ABP derivatives. In male CD rats, these N-OH-AS derivatives produced peritesticular mesothelioma and tumors of the pancreas and ear duct. N-OH-PAS also produced tumors of the small intestine and lung. The acetyl and propionyl derivatives were more carcinogenic than the formyl derivative of N-OH-AS for both male and female CD rats, suggesting that cytosolic acetyltransferases may be more important than the microsomal ones in activating these carcinogens. PMID- 9366899 TI - The reactivity of o-quinones which do not isomerize to quinone methides correlates with alkylcatechol-induced toxicity in human melanoma cells. AB - Catechols are widespread in the environment, especially as constituents of edible plants. A number of these catechols may undergo oxidative metabolism to electrophilic o-quinones (3,5-cyclohexadien-1,2-dione) by oxidative enzymes such as cytochrome P450 and peroxidases. Alkylation of cellular nucleophiles by these intermediates and the formation of reactive oxygen species, especially through redox cycling of o-quinones, could contribute to the cytotoxic properties of the parent catechols. In contrast, isomerization of the o-quinones to electrophilic quinone methides (4-methylene-2,5-cyclohexadien-1-one, QM) could cause cellular damage primarily through alkylation. In this investigation, we treated human melanoma cells with two groups of catechols. These cells have high levels of tyrosinase required to oxidize catechols to quinoids. For catechols which are oxidized to o-quinones that cannot isomerize to quinone methides or form unstable quinone methides, plots of the cytotoxicity data (ED50) versus the reactivity of the o-quinones gave an excellent linear correlation; decreasing o-quinone reactivity led to a decrease in the cytotoxic potency of the catechol. In contrast, catechols which are metabolized by the o-quinone/p-quinone methide bioactivation pathway were equally cytotoxic but showed no correlation between the reactivity of the o-quinones and the cytotoxic potency of the catechols. The most likely explanation for this effect is a change in cytotoxic mechanism from o quinone-mediated inhibition of cell growth to a bioactivation pathway based on both o-quinone and p-QM formation. These results substantiate the conclusion that the involvement of the o-quinone/ QM pathway in catechol toxicity depends on a combination between the rate of enzymatic formation of the o-quinone, the rate of isomerization to the more electrophilic QM, and the chemical reactivity of the quinoids. PMID- 9366900 TI - Comparisons of the binding of [14C]radiolabelled tamoxifen or toremifene to rat DNA using accelerator mass spectrometry. AB - Tamoxifen, widely used as adjuvant therapy in the treatment of breast cancer, is now undergoing trials as a cancer chemopreventative agent. Previous work has shown an association between 32P-postlabelled adducts in rat liver DNA and the development of liver tumours. With the use of accelerator mass spectrometry, [14C]tamoxifen was shown to bind to liver DNA of female rats in a dose-dependent manner and was linear over 0.1-1 mg/kg, compatible with the therapeutic dose used in women (20 mg/person per day). Radiolabel could also be detected in extrahepatic organs, including reproductive and GI-tract, where levels were about 18 and 46%, respectively those seen in liver. Following enzymatic hydrolysis of liver DNA, normal nucleotides by HPLC showed < 2% incorporation of the [14C]radioactivity while > 80% appeared as non-polar products. In contrast, when animals were given an equivalent dose of [14C]toremifene, binding to DNA was an order of magnitude lower than that seen with tamoxifen and no evidence of non polar adducted nucleotides following HPLC. However, in vitro, using human, rat or mouse liver microsomal preparations, NADPH-dependent binding of both toremifene and tamoxifen to calf thymus DNA could be demonstrated, suggesting that under favourable circumstances toremifene is capable of undergoing conversion to reactive intermediates. PMID- 9366901 TI - Frequency and cell specificity of T-cell receptor interlocus recombination in human cells. AB - Immunoglobulin and T-cell receptor (TCR) genes are assembled by a site-specific rearrangement known as V(D)J [variable-(diversity)-joining] recombination. These rearrangements occur normally in pre-B- and pre-T-cells using signal sequences adjacent to coding exons for immunoglobulin and TCR genes, respectively. However, aberrant recombination may result in the generation of hybrid TCR genes by joining of TCR-beta with TCR-gamma specific sequences. Such hybrid TCR genes occur at a low frequency in peripheral blood lymphocytes (PBL) of healthy individuals, and can be detected by PCR amplification. We have determined the in vivo frequency of hybrid V gamma-J beta 1 TCR (hybrid TCR) genes in lymphocyte DNA from 12 healthy individuals. The average frequency was found to be 5.83 in 0.75 x 10(6) PBL, with a threefold difference between the highest and lowest individual value. The presence of similar TCR gene rearrangements in individual samples suggests that T-cells with a hybrid TCR gene are capable of clonal expansion in vivo. The individual hybrid TCR gene frequency remained relatively constant during 72 hours of in vitro cultivation. In long-term culture, the frequency gradually decreased, and after 28 days no hybrid TCR genes were detectable in lymphocyte DNA. These results show that T-cells with a hybrid TCR gene are able to respond to mitogen stimulation in vitro, and may have a proliferative disadvantage or are selected against during prolonged in vitro cultivation. No hybrid TCR genes were detected in ten proliferating T-cell clones, indicating that the rate of hybrid TCR gene formation is < 2.0 x 10(-8) per cell per cell division. No hybrid TCR genes were detected in DNA from B lymphocytes, sperm, granulocytes, fibroblasts, keratinocytes, and three B lymphoblastoid ataxia telangiectasia cell lines. In agreement with previous reports, the frequency of hybrid TCR genes in peripheral blood DNA from two ataxia telangiectasia patients was found to be more than 15-fold higher than in lymphocytes from normal individuals. These data show that formation of hybrid TCR genes is restricted to T-cells in vivo, and occurs at a very low frequency, if at all, in proliferating T-cells in vitro, and with an increased frequency in patients with ataxia telangiectasia. PMID- 9366902 TI - Induction of germline-length mutations at the minisatellites PC-1 and PC-2 in male mice exposed to polychlorinated biphenyls and diesel exhaust emissions. AB - PC-1 and PC-2 are hypervariable mouse minisatellites. The rates of spontaneous germline-length mutation have been shown to vary between different mouse strains. PC-1 is composed of GGCAG repeat units and PC-2 of GGCAGGA. Minisatellites frequently mutate by gaining or losing repeat units. Such length mutations in mini- and microsatellites have been associated with human disease and may therefore be an important endpoint in genetic toxicity testing. Carcinogenic activity of many chemicals is associated with their ability to induce heritable mutations. Since minisatellites are highly prone to mutate to new lengths, which can be assayed by Southern analysis, we used this method to detect heritable genetic effects in mice. Male mice exposed to diesel exhausts and/or polychlorinted biphenyls (PCB) were investigated for effects on the germline mutation frequenallele lengths in parents and offspring. For PC-1 significantly higher mutation frequencies were found in males treated with diesel exhausts + PCB (6 of 35 alleles) and with PCB alone (6 of 51 alleles) as compared to the males in the control group (0 of 43 alleles). The mutation frequency in the diesel exhaust group was not significantly increased (2 of 43 alleles). For PC-2 the only mutation found occurred in the PCB group (1 of 51 alleles). This in vivo study demonstrates--for the first time--chemically induced minisatellite mutations in the germline. PMID- 9366903 TI - Detection of low copy number inversions in mouse genomic DNA with unidirectional PCR primers. AB - The recessive brachypodism (bp) mutation, located in the growth/differentiation factor 5 (GDF5) gene, causes highly specific skeletal changes in the limbs of brachypod mice. Although Southern blot analysis does not distinguish sequence disruptions in the GDF5 sequence of brachypod mice, sequencing and mapping GDF5 mRNA reveals the bp mechanism to be an inversion preceded by a small deletion. We report here a simple and sensitive method of bp detection from mouse genomic DNA. Previous bp detection used degenerative PCR sequencing. However, without automation, sequencing is a laborious effort for GDF5 inversion detection. The method developed utilizes two unidirectional primers in PCR (UP-PCR), which allow for quick and sensitive analysis of gel electrophoresed PCR products. UP-PCR of the GDF5 gene in wildtype mouse genomic DNA cannot amplify a fragment due to the unidirectional primers. However, UP-PCR of the GDF5 gene in bp mouse genomic DNA does amplify a fragment from the GDF5 gene. Amplification occurs because of the inverted fragment in bp GDF5. This fragment changes the direction of the second forward primer 180 degrees to the position of a reverse primer. UP-PCR detection of the bp inverted fragment is highly sensitive. Amplified fragments were obtained from the bp genomic DNA in the presence of wildtype genomic DNA in ratios up to 1:10(6), respectively. The sensitivity and simplicity of this method allow for quick, inexpensive, and reliable detection of the bp inversion. PMID- 9366904 TI - Persistence of radiation-induced translocations in rat peripheral blood determined by chromosome painting. AB - In this article, we address the issue of persistence of chromosome exchanges following acute in vitro exposure of rat peripheral blood to 137Cs. Irradiation occurred 24 hr after culture initiation, and metaphase chromosomes were prepared 2, 3, 4, and 5 days later. Chromosomes 1, 2, and 4 were painted in unique colors and scored for structural aberrations. Dicentric chromosomes and acentric fragments diminished rapidly with time, as expected. Translocations exhibited greater persistence, but still showed a reduction in frequency, reaching a plateau of approximately 65 and 55% of their initial values, 4 days after exposure to 1 and 2 Gy, respectively. An exponentially declining model was fit to the combined dicentric, acentric fragment, and translocation frequencies, which showed that all three aberration types declined at equivalent rates. The frequencies of dicentrics and fragments declined to a plateau of zero, while translocations reached a plateau at frequencies significantly greater than zero. The decline in translocations with time is inconsistent with prevailing theoretical expectations, but is consistent with a model where some translocations are fully stable (persistent) and some are unstable (not persistent) through cell division. These results may have implications for radiation biodosimetry in humans. PMID- 9366905 TI - Spectrum of spontaneous mutations in liver tissue of lacI transgenic mice. AB - The advent of transgenic technology has greatly facilitated the study of mutation in animals in vivo. The Big Blue mouse system, transgenic for the lacI gene, permits not only the quantification of mutations in different tissues but also provides for the generation of in vivo-derived mutational spectra. This report details the sequence alterations of 348 spontaneous mutations recovered from the liver of 6-8-week-old male Big Blue mice. The spectra recovered from two strains of mice, C57BI/6 and B6C3F1, were compared and found to be very similar. The predominant mutations are G:C-->A:T transitions, with 75% of these occurring at 5'-CpG-3' sequences. This mutational bias is consistent with deamination-directed mutation at methylated cytosine bases. The second most common class of mutations is G:C-->T:A transversions. A significant clonal expansion of mutants was found in several animals, and this was used to make an approximate correction of the mutant frequency such that the most conservative estimate of mutation frequency is presented. The establishment of this substantial database of spontaneous mutations in the liver of Big Blue mice is intended to serve as a reference against which mutations recovered after treatment can be compared. PMID- 9366906 TI - B[a]P-DNA adduct formation and induction of human epithelial lung cell transformation. AB - In this study we tested the suitability of the human epithelial lung cell line BEAS-2B for in vitro studies of lung carcinogenesis. The human bronchial epithelial lung cell line BEAS-2B, immortalized with an SV-40/Ad-12 hybrid virus construct, was treated for 24 hours with five different concentrations of the lung carcinogen benzo(a)pyrene (B[a]P) to assess the relationship between DNA adduct levels, cell cycle distribution, micronuclei formation (MN), colony forming efficiency (CFE), and anchorage independent growth (AIG). There appeared to be a strong linear correlation between B[a]P concentration and DNA adduct formation, but no difference in cell cycle distribution was observed after incubation with various concentrations of B[a]P. In the incubation range of 4 to 100 nM B[a]P, the number of DNA adducts was linearly correlated with colony formation in AIG and with the number of cells within individual colonies but not the number of colonies in the CFE test. At higher B[a]P concentrations, the clonal expansion of cells in the CFE and the number of colonies in the AIG declined. Also, the number of micronuclei increased with the formation of DNA adducts. It is concluded that after 24 hours of incubation with 100 nM B[a]P, the formation of BPDE-DNA adducts in the human epithelial lung cells BEAS-2B results in maximal induction of cell transformation. Because of this correlation between DNA adduct formation and lung epithelial cell transformation, the BEAS-2B cells seem suitable for in vitro studies on lung carcinogens. PMID- 9366907 TI - Detection of micronuclei in peripheral erythrocytes of Cyprinus carpio exposed to metallic mercury. AB - Cyprinus carpio fish (carp), exposed to elemental or metallic mercury (Hg0) at concentrations of 2.0, 20.0, and 200.0 mg per liter of water, were kept in concrete tanks for 159 days. Ten fish were used for each concentration level. Thirteen samples of peripheral blood were collected from each animal through gill puncture, 12 during the first 90 days of the experiment, and the last one at the end of the experiment. The micronucleus test (MNT) was designed to study dose and time yield effects of mercury after indirect exposure in vivo. The results indicated that for a concentration of 2.0 mg Hg0/l, there was no significant increase in frequency of micronuclei (MN), but at higher concentrations (20.0 and 200.0 mg Hg0/l) there was a significant increase in MN frequencies. This effect was higher after 31 days of exposure, followed by slight stabilization and gradual decrease. PMID- 9366908 TI - Mutagenicity of HPLC-fractionated urinary metabolites from 2,4,6-trinitrotoluene treated Fischer 344 rats. AB - The production and storage of explosives has resulted in the environmental accumulation of the mutagen 2,4,6-trinitrotoluene (TNT). In order to characterize the production of mutagenic urinary metabolites, 6-week old male Fischer 344 rats were administered 75 mg of TNT/kg or DMSO vehicle by gavage. The animals were placed into metabolism cages, and urine was collected for 24 hr. Following filtration, metabolites in the urine were deconjugated with sulfatase and beta glucuronidase and concentrated by solid phase extraction. The eluate was fractionated by reverse-phase high-performance liquid chromatography (HPLC) using acetonitrile/water, and the fractions, were solvent exchanged in DMSO by nitrogen evaporation. Each HPLC fraction was bioassayed in strains TA98, TA98NR, TA100, and TA100NR without metabolic activation using a microsuspension modification of the Salmonella histidine reversion assay. Fractions 3, 5-18, 21, 22, and 24-26 contained mutagens detected by strain TA98. In the nitroreductase-deficient strain TA98NR, some mutagenic activity was lost; however, fractions 3, 6, 9-11, 15, and 25 clearly contained direct-acting mutagens. Fewer fractions were positive in strain TA100 (9-16, 19, 20, and 25) with less activity observed in the nitroreductase deficient strain TA100NR (fractions 3, 12, 14, 15, and 25). Although some mutagenic activity coeluted with known TNT metabolite standards, there were still many unidentified mutagenic peaks. PMID- 9366909 TI - Activation and detoxification of dinitropyrenes by cytosol and microsomes from Aroclor-pretreated rats in the Ames and umu assays. AB - 1,3-, 1,6-, and 1,8-Dinitropyrene (1,3-, 1,6-, and 1,8-DNP) are direct-acting mutagens in that they do not require an exogenous source of enzymes for activation to mutagens in the Ames assay. However, the addition of mammalian S9 preparations, or the microsomal and cytosolic compartments comprising S9, modulate the mutagenic response of these DNPs. In this study, we compared the mutagenic response of these DNPs in the presence of cytosol and microsomal fractions from the liver of Aroclor-pretreated (AR) and control rats, in the Ames mutagenicity assay and umu gene induction assay. 1,3- and 1,8-DNP were deactivated to a greater extent by microsomes from AR-induced and control rats than was 1,6-DNP, in both the umu and Ames assays. In the Ames assay, S9 was more potent in deactivating the DNP than an equivalent concentration of microsomes from the same S9 preparation. Also, S9 from AR-pretreated rats deactivated the isomers to a greater extent than S9 from control rats. In contrast to the constant deactivation of all the isomers in the two assays catalyzed by microsomes and S9, the response with cytosol from AR-pretreated rats differed with respect to the three isomers in the Ames and umu assays. When cytosol from AR-treated rats was added, the mutagenicity of 1,3- and 1,6-DNP, but not 1,8-DNP, was significantly (P < 0.05) increased in the Ames assay while the mutagenicity of the three DNPs was increased in the umu assay. Also, a biphasic response was observed in the umu assay with 1,6- and 1,8-DNP, in that AR-cytosol enhanced the mutagenicity at low protein concentrations (5-50 micrograms protein/reaction) but abrogated the response at higher protein concentrations. The effect of cytosol from control rats depended on the isomer tested; 1,3-DNP was activated above the background level in both assays (nearly towfold) while 1,6-DNP and 1,8-DNP were only activated at low protein concentrations in the umu assay. In the Ames assay, cytosol from AR-pretreated rats did not alter the mutagenic response with 1,8 DNP, while control cytosol significantly (P < 0.05) deactivated 1,8-DNP at all substrate concentrations tested. In summary, this study showed that the mutagenicity of 1,3-DNP was similar in the two assays but the responses with 1,6- and 1,8-DNP differed in the two assays. These isomeric differences could be due to the varying metabolic pathways of the three DNPs as well as the detectable end points of the two assays. PMID- 9366910 TI - Mutagenic synergy between paraoxon and mammalian or plant-activated aromatic amines. AB - Paraoxon (diethyl-p-nitrophenylphosphate) is the toxic, but non-mutagenic metabolite of the organophosphorus ester (OP) insecticide parathion. Although this agent has been used as a deacetylase inhibitor in many studies, we discovered a mutagenic synergy with paraoxon and plant-activated m phenylenediamine or with direct-acting 2-acetoxyacetylaminofluorene in Salmonella typhimurium cells [Gichner T et al. (1996): Environ Mol Mutagen 27; 59-66]. In the present study, mammalian-activated m-phenylenediamine, o-phenylenediamine, p phenylenediamine, benzidine, 2,3-diaminophenazine or 2-aminofluorene, as well as plant-activated benzidine or 2-aminofluorene expressed an elevated mutagenic potency when assayed with S. typhimurium strain YG1024 in the presence of paraoxon. Under non-toxic conditions, paraoxon amplified the S. typhimurium mutant yield induced by these aromatic amines between 1.9-fold and 8.4-fold. Spectrophotometric analysis demonstrated that the rate of degradation of 2 acetoxyacetylaminofluorene was not significantly different in phosphate buffer with or without paraoxon or with S. typhimurium cytosol with or without paraoxon. Also paraoxon-mediated mutagenic synergy does not appear to be due to a direct reaction with aromatic amines. Mutagenic synergy between aromatic amines and OP oxon products may be a cause of concern because people are chronically exposed to environmental and dietary aromatic amines, and a significant segment of the U.S. population tested positive for OP insecticide residues. PMID- 9366911 TI - Preferential formation of deletions following in vivo exposure of postmeiotic Drosophila germ cells to the DNA etheno-adduct-forming carcinogen vinyl carbamate. AB - DNA sequence changes induced in the vermilion gene of Drosophila following in vivo treatment of postmeiotic male germ cells with vinyl carbamate (VCA), an etheno-adduct-forming carcinogen, are primarily deletions. With VCA, 65% (13/20) of the vermilion mutants isolated from crosses of NER+ (nucleotide excision repair) males with NER+ females and 40% (6/15) obtained from matings with NER- females were intra- or multi-locus deletions. Due to the insufficiently low mutagenic activity in NER+ genotypes of vinyl bromide (VB), another epsilon adduct-forming carcinogen, vermilion mutants could only be isolated from crosses of VB-treated males with NER- females. Of 14 vermilion mutants induced by VB, three carried large deletions. Twenty-two of 23 base substitutions derived from either VCA or VB experiments fell into one of the four categories expected from epsilon-adducts: three vermilion mutants had GC-->AT transitions, five had AT- >GC transitions, 7 carried GC-->TA transversions, and 7 were AT-->TA transversions. In view of the similarities in the response of mouse and Drosophila germ lines to several classes of alkylating agents, a high incidence of deletions is predicted to occur as well in postmeiotic germ cells of mice exposed to these types of agents. PMID- 9366912 TI - Involvement of nitroreductase and O-acetyltransferase on the mutagenicity of plant-activated benzidine and 4-aminobiphenyl. AB - Benzidine and 4-aminobiphenyl (4-ABP) are activated by intact plant cells and cell free TX1MX into mutagenic metabolites that induce frameshift and base pair substitution mutations in Salmonella typhimurium. The plant activation of these agents is plant peroxidase-mediated and bacterial O-acetyltransferase (OAT) dependent. TX1MX-activated benzidine and 4-ABP were analyzed with S. typhimurium frameshift tester strains, YG1021, YG1024, TA98, TA98NR, TA98/1,8-DNP6, MP219, and base pair substitution tester strains, YG1026, YG1029, TA100, TA100NR, TA100TN:OAT, and MP208. Concentration ranges for benzidine and 4-ABP were 1-50 microM and 0.1-1 mM, respectively. This study was conducted to determine if the plant-activation of benzidine and 4-ABP follows the prostaglandin H synthase mediated activation pathway in mammals [Smith et al. (1992): Chem Res Toxicol 5;431-439]. In this model, benzidine is N-acetylated by S. typhimurium OAT. This acetylated product is a substrate for PHS and is converted into a 4-nitro product which is catalyzed by nitroreductase into a N-hydroxy intermediate. The pathway assigns a specific role for nitroreductase in the activation of benzidine. By employing S. typhimurium strains that express different levels of OAT and/or nitroreductase, we determined that the plant-activation of benzidine and 4-ABP has an absolute requirement of bacterial OAT activity for the induction of frameshift mutations at hisD3052 and is required for the optimal mutagenic response at hisG46. Nitroreductase also plays a role in the plant activation of these agents. The data suggest that the plant-activation of benzidine and 4-ABP generates at least two classes of proximal mutagenic intermediates. One class requires S. typhimurium OAT alone to be transformed into the ultimate mutagen and a second class requires both OAT and nitroreductase. PMID- 9366914 TI - Antimutagenic activity of natural xanthophylls against aflatoxin B1 in Salmonella typhimurium. AB - Carotenoids (carotenes and xanthophylls) are excellent antioxidants with antimutagenic and anticarcinogenic properties. They occur naturally in some foods such as carrots, red tomatoes, butter, cheese, paprika, palm oil, corn kernels, Marigold petals, annatto, and red salmon. In the present study, we used the Salmonella plate incorporation test to examine the effect of xanthophylls extracted from Aztec Marigold (Tagetes erecta) on the AFB1 mutagenicity, using tester strain YG1024. The effect of lutein on the DNA-repair system in YG1024 was investigated by a pre-incubation test. In a dose-response curve of AFB1, the mutagenic potency was 1,031 revertants/nmol. The dose of 0.5 microgram AFB1/ plate was chosen for the antimutagenicity studies. Pure lutein and xanthophylls from Aztec Marigold flower (oleoresin and xanthophyll plus) inhibited the mutagenicity of AFB1 in a dose-dependent manner. The pigments were more efficient at inhibiting the AFB1 mutagenicity than pure lutein. The percentages of inhibition on AFB1 mutagenicity were 37, 66, and 76% for lutein, oleoresin, and xanthophyll plus at the dose of 2 micrograms/plate, respectively. Lutein had a modest effect on the DNA-repair system of YG1024. In spectrophotometric studies, a new absorption peak was detected at 378 nm when lutein and AFB1 were incubated together, and lutein reacted with AFB1 metabolites. The results suggest that the inhibitory mechanism of lutein against AFB1 mutagenicity is most probably the result of a combination of the following events: formation of a complex between lutein and AFB1, direct interaction between lutein and AFB1 metabolites, and finally that the lutein may also affect the metabolic activation of AFB1 by S9 and the expression of AFB1-modified Salmonella DNA. PMID- 9366913 TI - Antimutagenic and promutagenic activity of ascorbic acid during oxidative stress. AB - Ascorbic acid (AA) has both antioxidant and prooxidant activities. However, there have not been any studies to elucidate the molecular mechanisms that determine whether AA functions as an anti- or a prooxidant during oxidative stress. The results of this study, using the Chinese hamster ovary cell line AS52 as a model system, demonstrate that there is a temporal relationship between the anti- and prooxidant activities of a physiologically relevant concentration of AA (50 microM) and oxidative stress. Treatment of cells with AA (50 microM) 24 hr prior to treatment of the cells with a radical generating system (RGS) results in a statistically significant inhibition of the cytotoxicity and mutagenicity associated with exposure of AS52 cells to oxidative stress. Conversely, cotreatment of cells with AA and the RGS results in a statistically significant increase in both the cytotoxic and mutagenic effects of oxidative stress when compared to cell populations exposed only to the RGS. The results, using a novel histochemical-computer image analysis system to detect hydrogen peroxide (H2O2), also demonstrate that there is a direct correlation between the ability of AA to decrease the levels of H2O2 in cells and the cytotoxic and mutagenic effects of oxidative stress. This study suggests that the time at which AA is administered in relation to exposure to oxidative stress has an impact on AA antimutagenic activity, and this may explain the conflicting results concerning the effectiveness of AA as a cancer chemopreventive agent. PMID- 9366915 TI - Evaluation of positive controls for the in vitro unscheduled DNA synthesis assay using hepatocytes from induced (Aroclor 1254) and uninduced male cynomolgus monkey. AB - We have evaluated the use of four different positive control compounds for assessing UDS in monkey hepatocytes and have found three of these, methylmethanesulfonate, benzo[a]pyrene, and dimethylbenz[a]anthracene, to produce strong positive responses in vitro. Dimethylnitrosamine induced only weak responses. We also report that the strength of the response induced by procarcinogens was not enhanced in hepatocytes taken from Aroclor 1254-pretreated monkeys, even though substantial induction of cytochrome P450 enzymes was demonstrated in these cells. These studies raise the question of the utility of employing an in vivo induction system to enhance the monkey UDS assay. PMID- 9366916 TI - Metabolic cooperation in the selection of thioguanine-resistant mutants does not occur with the human B-lymphoblastoid cell TK6. AB - Selection for thioguanine resistant mutants in the human B-lymphoblastoid cell TK6 yields the same results in both round and flat bottom 96-well microtiter plates. These results suggest that metabolic cooperation is not an issue in these cells and show that round bottom wells can be used in place of flat bottom wells. PMID- 9366917 TI - Lymphocyte subsets during and after rabbit anti-thymocyte globulin induction in pediatric renal transplantation: sustained T cell depletion. PMID- 9366918 TI - Seven-year experience with rabbit antithymocyte globulin after cardiac transplantation at the Montreal Heart Institute. PMID- 9366919 TI - Use of thymoglobulin induction therapy in the prevention of acute graft rejection episodes following liver transplantation. PMID- 9366920 TI - Use of rabbit anti-thymocyte globulin for induction immunosuppression in high risk kidney transplant recipients. PMID- 9366921 TI - The US compassionate experience with thymoglobulin for the treatment of resistant acute rejection. PMID- 9366922 TI - Thymoglobulin reverses acute renal allograft rejection better than ATGAM--a double-blinded randomized clinical trial. PMID- 9366923 TI - Pharmacokinetics, foreign protein immune response, cytokine release, and lymphocyte subsets in patients receiving thymoglobuline and immunosuppression. AB - The pharmacokinetics and immune response to the rabbit IgG of rabbit antihuman thymocyte globulin, Thymoglobuline has been characterized. A cytokine release pattern of TNF alpha and IL-6 but not IL-1 beta and IFN chi has been demonstrated with the first and not subsequent doses. An effect on lymphocyte depletion of peripheral blood with major subset suppression has been shown to last more than the 3-month observation period in patients on a regimen of quadruple sequential immunosuppression. PMID- 9366924 TI - Single center experience with thymoglobulin in renal transplantation. PMID- 9366925 TI - Induction therapy with rabbit antithymocyte sera reduces rejection episodes in immunologically low-risk living donor renal transplant recipients. PMID- 9366927 TI - Pancreas transplantation with ATG vs OKT3. PMID- 9366926 TI - Risk-benefit of OKT3 prophylaxis in immunologic high-risk cadaver kidney transplant recipients. PMID- 9366928 TI - The Radiometer Prize for priceless achievements. PMID- 9366929 TI - Residual neuromuscular block is a risk factor for postoperative pulmonary complications. A prospective, randomised, and blinded study of postoperative pulmonary complications after atracurium, vecuronium and pancuronium. AB - BACKGROUND: After anaesthesia involving pancuronium a high incidence of both residual neuromuscular block and postoperative pulmonary complications (POPC) has been reported. The aim of this study was to compare the incidence of POPC following the use of pancuronium, atracurium, and vecuronium, and to examine the effect of residual neuromuscular block on the incidence of POPC. METHODS: A total of 691 adult patients undergoing abdominal, gynaecological, or orthopaedic surgery under general anaesthesia were randomised to receive either pancuronium, atracurium, or vecuronium. Perioperatively, the response to train-of-four (TOF) nerve stimulation was evaluated manually. Postoperatively, the TOF ratios were measured mechanomyographically, and through a 6-day follow-up the patients were examined for pulmonary complications. RESULTS: The incidence of residual block, defined as a TOF ratio < 0.7, was significantly higher in the pancuronium group (59/226: 26%) than in the atracurium/vecuronium groups (24/450: 5.3%). In the pancuronium group, significantly more patients with residual block developed POPC (10/59: 16.9%) as compared to patients without residual block (8/167: 4.8%). In the atracurium/vecuronium groups, the incidence of POPC was not significantly different in patients with (1/24: 4.2%) or without (23/426: 5.4%) residual block. Multiple regression analysis indicated that abdominal surgery, age, long-lasting surgery, and a TOF ratio < 0.7 following the use of pancuronium were potential risk factors for the development of POPC. CONCLUSION: Postoperative residual block caused by pancuronium is a significant risk factor for development of POPC. PMID- 9366930 TI - Blockade of endogenous nitric oxide production results in moderate hypertension, reducing sympathetic activity and shortening bleeding time in healthy volunteers. AB - BACKGROUND: Short-term infusion of NG-monomethyl-L-arginine (L-NMMA) reversibly inhibits endogenous nitric oxide (NO) production in humans. We studied responses to more long-lasting (60 min) infusions, at doses high enough to cause effective inhibition of endogenous NO. METHODS: Eight healthy volunteers had catheters (pulmonary, arterial and venous) placed. Measurements included hemodynamics, endogenous NO levels in nasal air, bleeding time, and cyclic guanosine monophosphate (cGMP) and catecholamines in plasma. L-NMMA was infused at 0.3 mg.kg-1.min-1 during 30 min, followed by 0.15 (n = 6) or 0.3 (n = 2) mg.kg-1.min 1 during 30 min. RESULTS: L-NMMA significantly elevated mean arterial pressure by 12 +/- 3%, due to an increase in systemic vascular resistance. Cardiac output decreased by 23 +/- 3%, due to a decrease in stroke volume. Pulmonary vascular resistance (P < 0.05) increased, but mean pulmonary arterial pressure was stable. Forearm vascular resistance (P < 0.05) decreased. Bleeding time was shortened by 31 +/- 4% (P < 0.01). L-NMMA infusion reduced NO concentrations in nasal air by 64 +/- 2% (P < 0.01). Arterial pressure remained elevated and nasal NO remained depressed 90 min after the infusion, whereas most other responses were reversed at that time. Plasma cGMP showed only minor changes. Plasma norepinephrine decreased, suggesting reflexogenic inhibition of sympathetic activity, whereas epinephrine levels were low and stable throughout the experiment. CONCLUSION: Dosage of (13.5 mg.kg-1 in 60 min) L-NMMA infusion in humans was well tolerated. Pronounced and long-lasting inhibition of endogenous NO production, as evidenced by measurements in nasal air, resulted in unevenly distributed vasoconstriction, a transient decrease in cardiac output, and reflexogenic sympathetic withdrawal. Furthermore, bleeding time was shortened, suggesting platelet activation. PMID- 9366931 TI - Aortic cross-clamping influences regional net release and uptake rates of tissue type plasminogen activator in pigs. AB - BACKGROUND: The key regulator of intravascular fibrinolysis, tissue-type plasminogen activator (t-PA), is released from a dynamic endothelial storage pool. The aim of the study was to investigate regional t-PA net release and uptake rates in response to infra-renal aortic cross-clamping (AXC) and declamping (DC). METHODS: Anesthetized pigs were studied during 5 min of AXC, followed by a 35-min declamping (DC) period. Arterio-venous concentration gradients of total and active t-PA, as well as respective plasma flows, were simultaneously obtained across the preportal, hepatic, coronary and pulmonary vascular beds. Plasma levels of total t-PA (ELISA with purified porcine t-PA as standard), and active t-PA (spectrophotometric functional assay) were determined. RESULTS: Prior to AXC, we found a high net release rate of total t-PA across the preportal vascular bed (1700 ng.min-1 P < 0.001), and a high hepatic net uptake (4900 ng.min-1, P < 0.001), while coronary and pulmonary t-PA net fluxes were small and variable. AXC per se did not induce significant alterations in net fluxes of t-PA. Following DC, preportal and coronary net releases of total t-PA increased (to 2900 ng.min-1 and 60 ng.min-1, respectively). Despite an increase in hepatic net uptake of total t-PA (to 6100 ng.min-1) after DC, a significant increase in hepatic venous total t-PA occurred. CONCLUSIONS: The release and uptake of t-PA is indicated to be dynamic and organ-specific. DC induces an acute profibrinolytic reaction in preportal organs. The high hepatic t-PA uptake capacity restricts preportal profibrinolytic events to affect the systemic circulation. PMID- 9366932 TI - Mapping of punctuate hyperalgesia around a surgical incision demonstrates that ketamine is a powerful suppressor of central sensitization to pain following surgery. AB - BACKGROUND: Tissue injury induces central sensitization in the spinal cord dorsal horn neurons via mechanisms involving N-methyl-D-aspartate (NMDA) receptors, leading to secondary hyperalgesia. Using punctuate mechanical hyperalgesia as a measure of central sensitization, we examined whether induction and maintenance of central sensitization after surgery could be prevented by a low-dose infusion of the NMDA-receptor antagonist ketamine. METHODS: Twenty living kidney donors were included in a randomized, double-blind, parallel, two-group study. Before start of surgery 10 patients received an i.v. bolus of racemic ketamine 0.5 mg.kg 1, followed by a continuous i.v. infusion of ketamine 2 micrograms.kg-1.min-1 for 24 h, thereafter 1 microgram.kg-1.min-1 for another 48 h. The control group received placebo bolus and infusion. A standard general anaesthesia including fentanyl was used. Patient-controlled (PCA) i.v. morphine was used for postoperative analgesia. Punctuate mechanical hyperalgesia and temporal summation of mechanical stimuli causing "wind-up pain" were measured using von Frey filaments. RESULTS: The area of punctuate mechanical hyperalgesia was significantly reduced in the ketamine group 1, 3 and 7 d after the operation (P < 0.01-0.001). "Wind-up pain" was also reduced by ketamine (P < 0.05). PCA morphine consumption and pain intensity (visual analogue scale) differed between groups only during the first hours after surgery, in favour of ketamine. The ketamine patients scored significantly higher on a global satisfaction score. Side-effects were most frequent in the placebo group. CONCLUSION: Low-dose i.v. infusion of ketamine during and after surgery reduces mechanical punctuate hyperalgesia surrounding the surgical incision. These results indicate that blockade of NMDA receptors prevents the central sensitization caused by nociceptive input during and after surgery. PMID- 9366933 TI - Endogenous nitric oxide in the airways of different animal species. AB - BACKGROUND: High amounts of endogenous nitric oxide (NO) have been demonstrated in the human upper airway, but the role of nasal NO is still unclear. The present study aims to describe nasal NO excretion in different animal species with special living conditions or anatomy. METHODS: Domestic animals (horse, cow, pig, sheep, dog, cat) and zoo-animals (Rhesus monkey, chimpanzee, gorilla, elephant, fur seal, alpaca, yak, dolphin, camel, capybara, bear, tiger, wolf, giraffe, alligator, Harris' hawk, kangaroo) were studied awake, resting or anaesthetised. NO concentrations were measured by chemiluminescence using different analysers and techniques, including measurements on mixed exhaled air, during continuous or intermittent gas sampling, and on single breaths. RESULTS: Rhesus monkeys (number of individuals N = 5) and pigs (N = 2) were compared and displayed quite different excretion patterns. Allowing NO to accumulate in the nose during timed occlusions yielded peak concentrations in monkeys of 0.46 +/- 0.07 parts per million (ppm, mean +/- SEM), 0.59 +/- 0.08 ppm, 0.70 +/- 0.08 ppm and 1.02 +/- 0.05 ppm NO after 15, 30, 60 and 120 s of occlusion. In pigs, 0.012-0.021 ppm NO were recorded, independent of occlusion time. The chimpanzee was similar to the Rhesus monkey and the highest NO value, 2.9 ppm, was recorded after 4-5 min of occlusion. In single breaths from 3 elephants 0.031-0.082 ppm, from 1 gorilla 0.029 ppm, and from 1 chimpanzee 0.069 +/- 0.003 ppm NO (8 observations) were recorded. CONCLUSIONS: We found considerable species difference in nasal NO excretion with pronounced amounts only in primates and elephants. The physiological implications of these findings remain to be defined. PMID- 9366934 TI - Effect of thoracic epidural anaesthesia on ventilation-perfusion distribution and intrathoracic blood volume before and after induction of general anaesthesia. AB - BACKGROUND: Gas exchange is impaired during general anaesthesia due to development of shunt and ventilation-perfusion mismatching. Thoracic epidural anaesthesia (TEA) may affect the mechanics of the respiratory system, intrathoracic blood volume and possibly ventilation-perfusion (VA/Q) distribution during general anaesthesia. METHODS: VA/Q relationships were analyzed in 24 patients undergoing major abdominal surgery. Intrapulmonary shunt (Qs/QT), perfusion of "low" VA/Q areas, ventilation of "high" VA/Q regions, dead space ventilation and mean distribution of ventilation and perfusion were calculated from the retention/excretion data of six inert gases. Intrathoracic blood volume (ITBV) and pulmonary blood volume (PBV) were determined with a double indicator technique. Recordings were made before and after administration of 8.5 +/- 1.5 ml bupivacaine 0.5% (n = 12) or 8.3 +/- 1.8 ml placebo (n = 12) into a thoracic epidural catheter and after induction of general anaesthesia. RESULTS: Before TEA, Qs/QT was normal in the bupivacaine group (2 +/- 2%) and the placebo group (2 +/- 3%). TEA covering the dermatomal segments T 12 to T 4 had no effect on VA/Q relationships, ITBV and PBV. After induction of general anaesthesia Qs/QT increased to 8 +/- 4% (bupivacaine group, P < 0.05 and to 7 +/- 2% (placebo group, P < 0.05). ITBV and PBV decreased significantly to the same extent in the bupivacaine group and the placebo group. CONCLUSIONS: TEA has no effect on VA/Q distribution, gas exchange and intrathoracic blood volume in the awake state and does not influence development of Qs/QT and VA/Q inequality after induction of general anaesthesia. PMID- 9366935 TI - Ropivacaine 7.5 mg/ml for elective caesarean section. A clinical and pharmacokinetic comparison of 150 mg and 187.5 mg. AB - BACKGROUND: The new, long-acting local anaesthetic ropivacaine has shown less systemic toxicity than bupivacaine and a concentration of 7.5 mg/ml can therefore be used for epidural anaesthesia in Caesarean section. The present pilot study was undertaken to find indications for an optimal dosage by comparing the clinical effects, quality of anaesthesia and pharmacokinetics of ropivacaine 150 mg (lower dose = LD) vs 187.5 mg (higher dose = HD) for women undergoing elective Caesarean section under epidural anaesthesia. METHODS: Sixteen full-term women scheduled for elective Caesarean section in two equal-sized consecutive groups received 20 or 25 ml ropivacaine epidurally in this non-randomised, open study. Study parameters included sensory and motor blockade, circulatory response, intraoperative pain and discomfort, neonatal evaluation and pharmacokinetic determinations. RESULTS: Block height varied between T5 and T2 in the LD group, whereas the HD group produced 4 unnecessarily high blocks (C8 in 3 women and C7 in 1 woman). Surgical anaesthesia was excellent in both groups. Circulatory stability was pronounced in the LD group (no ephedrine given), while 4 women required ephedrine in the HD group. Neonatal outcome as judged by Apgar scores; umbilical blood gas determinations and NACS scores were excellent in both groups. The plasma concentration-time profiles indicated linearity in the concentration range studied, with similar clearance values to those reported previously. Placental drug equilibrium was rapid; however, the foetal drug exposure depended on intrauterine exposure time. CONCLUSIONS: 20-25 ml ropivacaine 7.5 mg/ml produced very satisfactory conditions for elective Caesarean section under epidural anaesthesia. In this small population, 150 mg ropivacaine seemed optimal, while 187.5 mg produced unnecessarily extended block height in 50% of the women. PMID- 9366936 TI - Comparison of inhalation inductions with xenon and sevoflurane. AB - BACKGROUND: Xenon is an odorless gas with low blood-gas solubility coefficient and without occupational and environmental hazards. This investigation was performed to evaluate the speed of induction, and respiratory and cardiovascular reactions to inhalation induction with xenon compared to an equianesthetic concentration of sevoflurane. METHOD: Twenty-four adult ASA 1-2 patients premedicated with 0.05 mg/kg of midazolam were instructed to take vital capacity breaths of 1 minimum alveolar concentration (MAC) of either xenon or sevoflurane until they lost consciousness. Induction time, total ventilatory volume, tidal volume, respiratory rate, minute ventilation, end-tidal MAC fraction, cardiovascular parameters and oxygen saturation were recorded. The patients were interviewed on the following day to evaluate their acceptability rating of the inhalation inductions. RESULTS: Compared to equianesthetic sevoflurane, xenon produced a faster induction of anesthesia (147 +/- 59 versus 71 +/- 21 s, respectively) with smaller decreases in respiratory rate, tidal volume and minute ventilation. Both agents showed comparable cardiovascular stability and oxygen saturation during induction. One patient in the sevoflurane group had breath holding and movements of extremities and another had only breath-holding. No patients in the xenon group experienced any complications. CONCLUSION: Xenon produced a faster induction of anesthesia without any complications than sevoflurane. Xenon had smaller decreases in tidal volume and respiratory rate during induction than sevoflurane. Xenon might offer an alternative to sevoflurane for an inhalation induction. PMID- 9366937 TI - Desflurane increases brain tissue oxygenation and pH. AB - BACKGROUND: Desflurane anesthesia can produce cerebral metabolic depression and increase cerebral blood flow. We evaluated the effect of desflurane on brain tissue oxygen pressure (PO2), carbon dioxide pressure (PCO2) and pH during neurosurgery. METHODS: Following a craniotomy, the dura was opened and a Paratrend 7 sensor, which measures PO2, PCO2, pH and temperature, was inserted into brain tissue. In 6 control patients in group 1, anesthesia was maintained constant with 3% end-tidal desflurane over 60 min, including a 30-min stabilization period. In group 2, 9 patients were ventilated with 3% desflurane under baseline conditions. After a 30-min stabilization period, baseline tissue gases and pH were measured and end-tidal desflurane was increased to 6% and then 9% for 15-min intervals. Mean arterial pressure (MAP) was maintained with intravenous phenylephrine. RESULTS: Under baseline conditions, cardiovascular and brain tissue measures were similar between the 2 groups. Increasing end-tidal desflurane from 3% to 9% produced burst-suppression EEG in all patients and significantly increased tissue PO2 and pH and decreased PCO2. No parameters changed significantly in the control group during steady-state anesthesia. CONCLUSION: These results show that 9% desflurane can improve brain tissue metabolic status before temporary brain artery occlusion if cerebral perfusion pressure is maintained. This may be particularly important in patients with symptoms of ischemia before surgery. PMID- 9366938 TI - Effective dose of granisetron in the reduction of nausea and vomiting after breast surgery. AB - BACKGROUND: Prophylactic use of granisetron, a selective 5-hydroxytryptamine type 3 receptor antagonist, reduces the incidence of nausea and vomiting after breast surgery. This study was undertaken to determine the minimum effective dose of granisetron in the reduction of postoperative nausea and vomiting (PONV) in patients undergoing general anaesthesia for breast surgery. METHODS: In a randomized, double-blind manner, 120 female patients aged 42-66 years were assigned to receive either placebo (saline) or granisetron in a dose of 20 micrograms.kg-1, 40 micrograms.kg-1 and 80 micrograms.kg-1 i.v. immediately before the induction of anaesthesia. A standard general anaesthetic technique was employed throughout. The PONV and safety assessments were performed continuously during the first 24 h after anaesthesia. RESULTS: There were no significant differences among the groups with regard to patient demographics, surgical procedures, anaesthetics administered and analgesics given. The incidence of PONV was 47%, 43%, 17% and 17% after administration of placebo and granisetron 20 micrograms.kg-1, 40 micrograms.kg-1 and 80 micrograms.kg-1, respectively. Granisetron 40 micrograms.kg-1 was as effective as 80 micrograms.kg-1 and both resulted in significant reductions of the incidence of PONV compared with placebo and granisteron 20 micrograms.kg-1 (P < 0.05). No differences in the incidence of adverse events were observed among the groups. CONCLUSION: Granisetron 40 micrograms.kg-1 appears to be the minimum effective dose for reducing PONV in patients undergoing general anaesthesia for breast surgery. PMID- 9366939 TI - Laryngeal mask bite blocks--rolled gauze versus Guedel airway. AB - BACKGROUND: Biting on the silicone tube and pilot balloon of the laryngeal mask airway (LMA) may obstruct or damage them with the teeth and a bite block is recommended. The recommended bite block is a wad of gauze swabs rolled into a cylindrical shape and placed alongside the LMA. It is considered that this avoids irritating the posterior pharyngeal wall and damage to teeth whilst supporting the LMA tube when taped to it. The Guedel airway is commonly used as a bite block with the tracheal tube and many anaesthetists also use it with the LMA. The aim of the following study was to compare rolled gauze swabs with a Guedel airway as a bite block for the LMA. METHODS: We compared the Guedel airway with rolled gauze swabs as a bite block for the laryngeal mask airway (LMA) in 120 ventilated patients in whom cuff pressures were limited to 5.87 kPa (60 cm H2O) and anaesthesia management was standardised. RESULTS: In the Guedel airway group, there was a higher incidence of ventilatory problems (0 vs 4, P < 0.05), bleeding (0 vs 8, P < 0.01), hoarseness (0 vs 4, P < 0.05) and sore throat (2 vs 12, P < 0.01). CONCLUSION: 1. The Guedel airway is an unsuitable bite block for the LMA. 2. Cuff pressure limitation is compatible with adequate ventilation. 3. The combination of LMA and Guedel airway probably prevents either from sitting in the correct anatomical position. PMID- 9366940 TI - Eltanolone for induction of anaesthesia in the surgical patient. A comparison of dose requirements in young and elderly patients. AB - BACKGROUND: The relative potency of the steroid anaesthetic agent eltanolone has been compared with respect to induction of anaesthesia in ASA I and II young (18 40 years) and elderly (> 65 years) patients. METHOD: 113 temazepam premedicated patients (60 elderly) were evaluated in an open randomised study. They were allocated to receive doses between 0.05 and 0.75 mg/kg given i.v. over 30 s. The first 33 patients formed a pilot phase; the formal study comprised 80 patients. The primary efficacy variable was loss of verbal contact within 120 s and an effect lasting more than 4 min. All patients breathed 100% oxygen throughout the study period. Safety data (heart rate, blood pressure, respiratory apnoea, involuntary movements, hypertonus and other adverse effects) were noted. RESULTS: Anaesthesia was adequately induced in 12/40 elderly and 7/40 young patients. The lowest effective induction dose was 0.2 mg/kg in elderly and 0.3 mg/kg in young patients. This gave a relative potency of 0.28 (95% CI 0.12-0.52; P = 0.0039). The cardiovascular effects associated with induction were small; other side effects included involuntary movement and hypertonus, and respiratory upsets (apnoea, hiccups and coughing). CONCLUSION: The effective induction dose of eltanolone was significantly lower in the elderly patients; but the drug safety profile was similar in both age groups of patients. PMID- 9366941 TI - Autoregulation and vasodilator responses by isoflurane and desflurane in the feline renal vascular bed. AB - BACKGROUND: Inhalational anesthetics have agent-specific effects on the renal circulation. This study investigated renal vasodilator responses produced by either autoregulation, 0.8% isoflurane (ISO) or 3.5% desflurane (DES). METHODS: We measured systemic mean arterial pressure (MAP-SYST; axillary artery), renal blood flow (QREN; perivascular ultrasound) and central venous pressure (CVP) in normoventilated cats (n = 8) during basal chloralose anesthesia (control) and after the addition of ISO and DES. Renal mean arterial pressure (MAPREN) was controlled by an aortic clamp. QREN was measured at pre-set-MAPREN levels of 50, 70 and 90 mmHg. Renal vascular resistance (RREN) was derived. RESULTS: When MAPREN was artificially restrained from 133 +/- 5 mmHg to 90 mmHg during control, RREN decreased by 35% and no significant change in QREN was observed, reflecting an intact autoregulation. RREN levels during ISO or DES at stages with unrestrained MAPREN (95 +/- 6 and 102 +/- 9 mmHg, respectively), were not significantly different from RREN at 90 mmHg during control. When MAPREN was artificially decreased below 90 mmHg, QREN decreased in a similar fashion among control and ISO/DES sequences. The autoregulatory capacity was not significantly different among these sequences. Between 90-70 mmHg, the autoregulatory capacity was reduced and not demonstrable below 70 mmHg. CONCLUSION: The renal autoregulatory capacity was not attenuated by either ISO or DES. These agents produced equipotent renal vasodilation, which was not more powerful than that produced by autoregulation alone. The renal vasorelaxant effects of ISO and DES may therefore to a substantial extent be attributable to autoregulation. PMID- 9366942 TI - Vectorcardiographic changes during laparoscopic cholecystectomy may mimic signs of myocardial ischaemia. AB - BACKGROUND: Laparoscopic surgery involves the use of intra-abdominal carbon dioxide insufflation (pneumoperitoneum). The increased intra-abdominal pressure causes marked haemodynamic changes, which may influence electrocardiographic monitoring. The aim of the present study was to elucidate the influence of pneumoperitoneum on vectorcardiographic recordings. METHODS: Vectorcardiographic changes (QRS vector difference = QRS-VD, QRS loop area, QRS magnitude, ST vector magnitude, spatial ST vector change) were recorded continuously applying computerized vectorcardiography in 12 anaesthetised cardiovascularly healthy patients, scheduled for laparoscopic cholecystectomy. Measurements were made before and during pneumoperitoneum in three different body positions (supine, Trendelenburg and reversed Trendelenburg), also employing transesophageal echocardiography and invasive blood pressure monitoring. RESULTS: Pneumoperitoneum significantly increased QRS-VD, in parallel with an enlargement in loop area and magnitude. The magnitude was significantly increased in the transversal and frontal planes and there was a tendency to increase the magnitude in the sagittal plane. The increase in QRS-VD reached levels previously associated with the development of myocardial ischaemia in patients with coronary artery disease. The ST-variables were not changed by the pneumoperitoneum. The positional changes also influenced QRS-VD significantly. CONCLUSIONS: When computerized vectorcardiography is used for ischaemia monitoring during pneumoperitoneum, the ST-variables seem reliable. However, vectorcardiographic QRS-changes should be interpreted with caution, as the QRS alterations found during pneumoperitoneum mimic the changes seen during myocardial ischaemia. PMID- 9366943 TI - The effects of cardiac surgery on early and late pulmonary functions. AB - BACKGROUND: Impaired pulmonary functions are common in cardiac patients. Early and late effects of cardiac surgery on pulmonary function tests (PFTs) are presented. METHODS: Fifty patients undergoing cardiac surgery (coronary artery bypass grafting [CABG, 74%], valve replacement or valvuloplasty [20%] and combined procedures [6%]) were studied. Anginal and cardiac failure symptoms severity, and smoking history, were evaluated preoperatively. PFTs were studied and compared pre-, and 3 weeks and 3.5 months postoperatively. RESULTS: Pre- and postoperative PFTs were inversely related to severity of preoperative symptoms. Forced vital capacity (FVC) dropped from 98% of predicted preoperatively, to 63% (P < 0.00001) and 75% (P < 0.00001) 3 weeks and 3.5 months postoperatively, respectively. Expiratory volume in the first 1 s of forced expiration (FEV1.0) decreased from 95% to 61% (P < 0.00001) and 70% (P < 0.00001), respectively. Forced expiratory flow at 50% of vital capacity (FEF50) decreased from 85% to 56% (P < 0.00001) and 59% (P < 0.00001). Forced expiratory flow at 75% of vital capacity (FEF75) decreased from 77% to 47% and 47% (P < 0.00001). Peak expiratory flow rate (PEFR) declined from 101% to 66% (P < 0.00001) and 86% (P < 0.003). Maximal voluntary ventilation declined from 103% to 68% (P < 0.00001) and 77% (P < 0.00001). Only FVC (P < 0.0003), FEV1.0 (P < 0.02) and PEFR (P < 0.0001) partially recovered postoperatively. Smoking history did not affect perioperative PFTs. Pre-, but not postoperative FVC, FEV1.0, FEF50 and FEF75 were worse in valve than in CABG patients. CONCLUSIONS: Pulmonary functions deteriorate significantly for at least 3.5 months after cardiac surgery. Preoperative cardiac ischaemic and failure symptoms are inversely related to perioperative PFTs. PMID- 9366944 TI - Influence of high-dose ketamine on the vascular reactivity of human and porcine isolated coronary artery segments. AB - The influence of ketamine on the vasomotor effect of histamine and serotonin was studied in isolated human and porcine coronary artery rings. Ketamine (10(-3) mol L-1) attenuated the contractile response to both mediators significantly (P < 0.05 for histamine concentrations of 3 x 10(-5) mol L-1 and above as well as for serotonin concentrations of 3 x 10(-8) mol L-1 and above). This effect of ketamine was observed in intact and endothelial denuded porcine rings (difference n.s.) as well as in coronary arteries from explanted human hearts of patients undergoing heart transplantation. It is concluded that this reduction of the contractile response to histamine and serotonin caused by ketamine is not dependent on the endothelial function (e.g. endothelium-derived relaxing factor). PMID- 9366945 TI - A positron emission tomography study of cerebral blood flow and oxygen metabolism in healthy male volunteers anaesthetized with eltanolone. AB - BACKGROUND: The effects of eltanolone anaesthesia in humans on regional cerebral blood flow, regional cerebral metabolic rate of oxygen and oxygen extraction ratio were to be evaluated using positron emission tomography (PET). METHODS: Six healthy male volunteers were studied. Series of PET-measurements with 15O and H2(15)O were carried out in the awake state (baseline)(n = 6), during eltanolone anaesthesia (n = 5) and during early recovery (n = 5), when the subjects were oriented with respect to person, place and time. Eltanolone was given as a programmed infusion. RESULTS: Cerebral blood flow (rCBF) was reduced in almost all cortex regions studied by 31 +/- 16% (mean +/- SD, P < 0.01). During recovery rCBF increased to 109 +/- 26% of pre-anaesthetic baseline levels (P < 0.01). Eltanolone in the doses administered lowered oxygen metabolism (rCMRO2) by 52 +/- 8% (P < 0.01) in cortex regions. During recovery rCMRO2 increased to 90 +/- 13% of baseline (P < 0.01). The oxygen extraction (OER) in cortical regions decreased by 32 +/- 23% (P < 0.01) during anaesthesia and returned to 82 +/- 10% of baseline (P < 0.01) during recovery. Less reduction in cortical blood flow during eltanolone anaesthesia was seen in the uncus (P < 0.01), though no differences in the depression of oxygen metabolism were seen. Oxygen extraction remained homogeneous throughout the brain. CONCLUSION: Eltanolone anaesthesia was shown to reduce cerebral oxygen metabolism and cerebral blood flow in healthy volunteers. There were no signs of ischaemic effects. PMID- 9366947 TI - Rupture of the left main-stem bronchus by the tracheal portion of a double-lumen endobronchial tube. AB - We report a rupture of the left main-stem bronchus following the insertion of a left-sided double-lumen endobronchial tube in a 76-yr-old woman with a short trachea. A fiberoptic bronchoscope was not used during the initial insertion of the tube and the depth of insertion resulted in approximately 5 cm in excess of the optimal level for this patient. The rupture had been caused by the tracheal portion of the double-lumen tube. This damage may have been avoided if a fiberoptic bronchoscope was used routinely as an introducer and for positioning of the endobronchial tube under direct vision. PMID- 9366948 TI - A rare post-anaesthesia complication causing upper airway obstruction. PMID- 9366946 TI - Contradictory effects of dopamine at 32 degrees C in pigs anesthetized with ketamine. AB - BACKGROUND: In critically ill patients who were surface cooled to 33 +/- 2 degrees C, we have observed that dopamine sometimes causes a substantial decrease in blood pressure. The present study was designed to compare the effects of dopamine in normothermia to those seen after surface cooling to 32 degrees C. METHODS: Seven pigs with a mean body weight of 21 kg were anesthetized with ketamine and muscle relaxation was induced with pancuronium. They were mechanically ventilated and given dopamine infusions (5 and 12 micrograms.kg 1.min-1)in normothermia and after surface cooling by cold water immersion to a central blood temperature of 32.0 degrees C (range 31.6-32.6 degrees C). RESULTS: In normothermia, dopamine at a dose of 5 micrograms.kg-1.min-1 increased mean arterial blood pressure (MAP) by 16% (P < 0.01) and cardiac output (CO) by 9% (P = 0.051); at 12 micrograms.kg-1.min-1 dopamine increased MAP by 26% (P < 0.01) and CO by 18% (P < 0.01). In hypothermia, MAP and CO did not change at an administration rate of 5 micrograms.kg-1.min-1; at 12 micrograms.kg-1.min-1 CO was unchanged but MAP was significantly reduced by 15% (P < 0.01). CONCLUSION: Dopamine increased CO and MAP in normothermia but not at 32 degrees C, where there was even a significant reduction of MAP in this porcine model. PMID- 9366949 TI - Hemidiaphragmatic paralysis following subclavian vein catheterization. AB - The right subclavian artery was inadvertently punctured during attempted preoperative insertion of a right subclavian venous catheter in a 59-yr-old woman undergoing radical hysterectomy. Large supraclavicular swelling became apparent soon after the arterial puncture. The postoperative chest X-ray obtained approximately 24 h after the catheterization revealed significant elevation of the right hemidiaphragm, which was further augmented on the 2nd to 4th postoperative days; oxygenation was concurrently impaired during these days. It was clinically judged that the hemidiaphragmatic paralysis was responsible for the elevated diaphragm. Both chest roentogenogram and arterial blood gas analyses started to improve on the 5th day, finally returning to normal on the 6th day. It is unlikely that the surgical procedure caused the paralysis, because it dealt only with the lower abdomen. Rather, the attempts at the subclavian venous catheterization probably caused the phrenic nerve paralysis, because the phrenic nerve travels very close to the subclavian vessels. Both the large haematoma formation following the arterial puncture and the time course of the paralysis suggest that compression of the right phrenic nerve by the haematoma, rather than needle trauma, was responsible for the paralysis. PMID- 9366950 TI - Adenosine and isoflurane concentrations. PMID- 9366951 TI - Aortic dissection after cardiopulmonary bypass detected by intraoperative transesophageal echocardiography. PMID- 9366952 TI - Cardiovascular response to infra-renal aortic cross-clamping. PMID- 9366953 TI - The combined spinal epidural (CSE) block. Clinical and experimental studies. PMID- 9366954 TI - Supersensitivity in rat micro-arteries after short-term denervation. AB - Contractile responses to phenylephrine and high-K+ were investigated in vitro in microvascular preparations from the rat medial plantar artery, a branch from the saphenous artery, obtained after short-term denervation in vivo. Two groups of animals were studied: (1) animals undergoing surgical resection of the saphenous nerve, and (2) animals undergoing surgical resection of both the sciatic and saphenous nerves. The animals were operated on one side only. Microvascular preparations (diameter about 325 microns) were obtained 10 days after surgery. Vessels from the non-operated side served as controls. Immunocytochemistry showed a decreased number of both neuropeptide Y (NPY) and calcitonin gene-related peptide (CGRP) immunoreactive nerve fibres in vessels after resection of the saphenous nerve only. Resection of both the saphenous and the sciatic nerve caused a complete loss of immunoreactive nerve fibres. Mechanical measurements were performed using a wire myograph. In vessels subjected to resection of the saphenous nerve the sensitivity to phenylephrine was similar to controls. Vessels denervated by resection of both the saphenous and sciatic nerves showed significant increases in phenylephrine and potassium sensitivity. When depolarized in high-K+ solution the denervated vessels showed an increased sensitivity to extracellular Ca2+. The results show that complete short-term denervation of the rat medial plantar artery in vivo causes a pronounced supersensitivity in the vascular smooth muscle. The supersensitivity appears not to be restricted to the sympathetic alpha-receptors but also associated with changes in the cellular excitation-contraction coupling. Such altered reactivity of the vascular smooth muscle may contribute to vascular disturbances observed in vivo after nerve damage or surgical denervation. PMID- 9366955 TI - Attenuation of forearm vasodilator responses to mental stress by regional beta blockade, but not by atropine. AB - Forearm blood flow during mental stress (Stroop's colour word conflict test) was studied in 18 healthy men before and during regional beta-adrenoceptor blockade (propranolol 0.5 mg), muscarinic receptor blockade (atropine 0.2 mg) and combined blockade, and compared with results obtained in untreated controls. Forearm blood flow was measured with venous occlusion plethysmography, and forearm vascular resistance was calculated. Arterial and venous blood sampling was performed for determination of adrenaline and noradrenaline in plasma. Mental stress increased heart rate, systolic and diastolic blood pressures and forearm blood flow, and lowered the forearm vascular resistance, to the same degree as in our previously studied controls. Neither of the intra-arterially administered drugs had any discernible systemic effects. Beta-blockade increased forearm vascular resistance by 32% and decreased forearm blood flow by 21% compared with unblocked levels during mental stress, whereas forearm vasodilation was maintained throughout the stress test in the control group (P < 0.05). Intra-arterial atropine had no certain effects. Arterial adrenaline levels during mental stress were similar in the receptor-blocked and control groups. In conclusion, the sustained forearm vasodilation during mental stress appears to be partly mediated via beta 2 adrenoceptor stimulation (i.e. by adrenaline), but we obtained no support for a cholinergic vasodilating mechanism. PMID- 9366956 TI - Effects of scorpion venom on central and peripheral circulatory response in an open-chest dog model. AB - Scorpion venom can induce in dogs severe haemodynamic changes leading to rapid rise in systemic blood pressure and cardiac output, followed by reduction of cardiac output and blood pressure within 1 h. The decrease in cardiac output is not related to myocardial dysfunction (Tarasiuk et al. 1994). We hypothesized that scorpion venom affects cardiac output by reducing venous return to the heart. Venous return was studied by steady-state measurements of cardiac output, the pressure gradient and resistance to venous return, in 16 dogs following injection of 0.05 mg kg-1 venom obtained from the scorpion species Leiurus quinquestriatus. In eight of the 16 dogs, atropine (0.1 mg kg-1) was given 15 min prior to venom injection (n = 4) or 85 min (n = 4) after venom administration. In five additional dogs, the stability of the preparation over time was evaluated following the same protocol without the injection of the venom. At 15 min, the venom induced an increase in blood pressure (80%) and cardiac output (250%) (P < 0.001) with little effect on heart rate. At 90 min, cardiac output and heart rate declined considerably below baseline (P < 0.001). Atropine prevented the decrease in heart rate, but did not affect the reduction of cardiac output. Five minutes after venom injection, mean circulatory pressure increased by 300% (P < 0.001), which was accompanied by a rightward shift of the venous return curve with no effect on resistance to venous return. At 120 min, mean circulatory pressure recovered and resistance to venous return remained at 40% (P < 0.01) above baseline. This study indicates that, in dogs, scorpion venom affects cardiac output by modifying the determinants of venous return. The initial increase in cardiac output is related to increased mean circulatory pressure since resistance to venous return did not change. The later fall in cardiac output is related to the reduction of mean circulatory pressure and increased resistance to venous return. PMID- 9366957 TI - The adrenal medulla as a wet sponge: a role for the intramedullary venous vasculature? AB - Synchronous contractions in the intramedullary venous vasculature have been postulated to assist in the discharge of hormones from the stimulated adrenal medulla in a manner analogous to the squeezing of a wet sponge. This study reports on two experimental approaches to support the hypothesis that contractions in the venous vasculature may contribute to the hormonal efflux. Firstly, the bovine adrenal medulla was perfused retrogradely via the bovine central adrenomedullary vein end changes in the vascular volume were assessed as changes in wet weight of the perfused tissue. Stimulation with acetylcholine and carbachol resulted in repetitive, transient weight losses, suggesting cholinergically mediated reductions in the vascular volume. Secondly, the contractile properties of the longitudinal layers of smooth muscle cells in the intramedullary venous system were characterized, using the bovine central adrenomedullary vein as a model. The results showed that the longitudinal layers of this vein were, similarly to the circular layers, selectively contracted by endothelin-1 via an ETA-like receptor, by neuropeptide Y and by membrane depolarization (high K+). However, the vein was insensitive to electrical stimulation acetylcholine and carbacho, as well as to catecholamines. These results suggest neuropeptide Y, released from the cholinergically stimulated chromaffin cells, as the most likely mediator of stimulus-evoked synchronous contractions of the venous vasculature in the bovine adrenal medulla. Together, these experiments provide support for the 'wet sponge' hypothesis for hormonal discharge from the adrenal gland. PMID- 9366958 TI - Serotonin inhibition of 1-methylxanthine metabolism parallels its vasoconstrictor activity and inhibition of oxygen uptake in perfused rat hindlimb. AB - The effect of serotonin (5-HT) on the metabolism of infused 1-methylxanthine (1 MX), a putative substrate of capillary endothelial xanthine oxidase (XO), and on the distribution of infused fluorescent microspheres (15 microns) by the artificially constant-flow perfused rat hindlimb preparation was investigated. 1 MX (5-100 microM) caused a slight inhibition of oxygen uptake (Vo2) but was not vasoactive, either alone or with 5-HT. 1-MX was converted to 1-methylurate (1-MU) and this conversion was inhibited by allopurinol and xanthine. 5-HT (0.35 microM), which caused vasoconstriction and decreased Vo2, also inhibited the conversion of 1-MX, indicated by a lowered venous perfusate steady-state 1-MU:1 MX ratio from 1.14 +/- 0.02 to 0.71 +/- 0.02 (P < 0.001), which is equivalent to the rate of conversion decreasing from 0.83 +/- 0.03 to 0.63 +/- 0.05 nmol min-1 g-1. This change closely followed the time course for changes in Vo2 and perfusion pressure and all three changes reversed in parallel when 5-HT was removed. Recoveries of 1-MU plus 1-MX at all times were high (100 +/- 5%). 5-HT did not act to inhibit XO. When compared with vehicle alone, 5-HT had either no effect (plantairs, gastrocnemius white, tibialis, extensor digitorum longus, vastus and thigh), or increased microsphere content (soleus and gastrocnemius red, P < 0.05) of muscles with only bone showing a significant decrease (P < 0.05). Since 5-HT did not inhibit XO or alter the net flow to individual muscles in this constant-flow model, the inhibition of conversion of 1-MX to 1-MU is concluded to be the result of a 5-HT-mediated decrease in the access of 1-MX to capillary XO within individual muscles. Possibilities include the redirection of flow to capillaries either in muscle or in connective tissue closely associated with muscle, where resistance is low and effective surface area is less. 1-MX has potential as a marker for muscle nutritive flow. PMID- 9366959 TI - Gender and age differences in transthoracic bioimpedance. AB - Thoracic impedance consists of a constant baseline component Z0 and a time variable component delta Z which represents the impedance change related to the cardiac cycle. The maximum part of delta Z [(dZ/dt)max] represents the peak of the ascending aortic blood flow. Measurements of basal thoracic impedance are affected by structural and anatomical differences in the thorax related to sex and ageing. This component is a variable in the denominator of Sramek's formula which is used for calculating stroke volume. The aim of this study was to elucidate the question as to whether the age- and sex-related variation in basal impedance may affect bioimpedance measurements of stroke volume. The study comprised 111 healthy subjects (55 males and 56 females) of ages between 20 and 69 years, divided according to age decades into five groups each of males and females. Stroke volume index (SI), Z0 and (dZ/dt)max were measured in every subject, using transthoracic bioimpedance cardiography. Z0 and (dZ/dt)max had significantly higher values in females than in males in every age group except the oldest one in the case of Z0 and the oldest two groups in the case of (dZ/dt)max. Stroke index showed no significant sex difference, although the higher Z0 in females may underestimate the values of stroke index. Elevation of (dZ/dt)max in females may therefore reflect a positive relation to Z0 rather than higher flow rates. Since Z0 and (dZ/dt)max are variants in opposite positions in Sramek's formula (denominator and numerator, respectively), this functional relationship may keep the bioimpedance measurements from being affected by the sex- and age-related changes in Z0. PMID- 9366960 TI - Effect of alveolar hypoxia on segmental pulmonary vascular resistance and lung fluid balance in dogs. AB - In a biventricular bypass preparation with constant-flow perfusion, pulmonary arterial pressure (Ppa), average pulmonary capillary pressure (Ppc), venous pressure (Pv), extravascular lung water volume (EVWd) and capillary permeability surface area product for urea (PS) were determined in control animals and in animals subjected to alveolar hypoxia. During hypoxia, Ppa increased in a biphasic manner, the site of hypoxic pulmonary vasoconstriction being located in the arterial upstream segment. At baseline, Ppc values were identical in control and experimental animals (3.4 +/- 0.4 vs. 3.6 +/- 0.2 mmHg). During 150 min of airway hypoxia, the rise in Ppc (5.1 +/- 0.3 mmHg) did not exceed the rise in Ppc (4.9 +/- 0.5 mmHg) recorded in control animals at same time interval during normoxic ventilation. EVWd increased during hypoxia to values significantly higher than those obtained in control animals (0.559 +/- 0.036 vs. 0.466 +/- 0.027 mL water g-1 lung). PS remained unchanged at baseline level throughout experiments in both groups of animals. Present data suggest that lung oedema formation during alveolar hypoxia may be caused by increased transcapillary fluid loss preferentially through transcellular hydraulic pathways in capillary endothelial cells. PMID- 9366961 TI - Effects of periodic obstructive apnoeas on superior and inferior venous return in dogs. AB - Obstructive apnoeas could cause flow limitation to venous return, resulting in a decrease in cardiac output and a change in the distribution of flow from the upper and lower body. In 14 anaesthetized dogs, we studied the effects of obstructive apnoeas on inferior and superior vena caval flows under baseline conditions and with intra-abdominal pressure increased by approximately equal to 5 torr by binding the abdomen. During obstructive apnoeas in the two groups, respiratory rate decreased by 30% (P < 0.02) and inspiratory airway pressure decreased by approximately equal to 15 torr (P < 0.01). At baseline, the ratio of inferior to superior vena caval flow was 2.4:1 and did not change with abdominal binding or apnoeas. During apnoeas there was no change in cardiac output or in the ratio of inferior to superior vena cava flow either with baseline or abdominal binding conditions. Preservation of total inferior vena caval flow during apnoeas and cardiac output occurred, even though inspiratory flow limitation was found with the abdomen bound. We conclude: (1) there was no change in either cardiac output or the distribution of venous return during apnoeas; (2) there was substantial inspiratory/expiratory variation in venous return during obstructive apnoeas. The large inspiratory-increase in venous return may have implications for the development of pulmonary hypertension during obstructive apnoeas. PMID- 9366962 TI - Altered antioxidant enzyme defences in insulin-dependent diabetic men with increased resting and exercise-induced oxidative stress. AB - Impaired antioxidant defences may predispose to the increased resting and exercise-induced oxidative stress found in patients with insulin-dependent diabetes mellitus (IDDM). We investigated major erythrocyte antioxidant enzyme activities at rest and in response to sustained, moderate intensity physical exercise in young diabetic men (n = 9) previously reported to have markedly elevated plasma lipid peroxidation and blood glutathione levels compared with control men (n = 13) (Laaksonen et al. 1996). At rest, erythrocyte glutathione reductase activity was 15% higher in the diabetic group (P = 0.049). Se glutathione peroxidase and glutathione-S-transferase activities were similar in both groups. Red cell Cu, Zn-superoxide dismutase and catalase activities were lower in the IDDM group (P = 0.033 and P = 0.023, respectively). After 40 min of exercise at 60% of the subjects' peak oxygen consumption, Se-glutathione peroxidase activity rose by about 14% in the control group (P = 0.003), but not in the IDDM group (P = 0.47). Exercise did not cause significant changes in other enzyme activities in either group. To conclude, lower erythrocyte Cu, Zn superoxide dismutase and catalase activity in young men with IDDM at rest may contribute to increased oxidative stress. On the other hand, increased glutathione reductase activity may represent a compensatory upregulation of glutathione homeostasis in response to increased oxidative stress. Upregulation of Se-glutathione peroxidase activity in response to physical activity appeared to be impaired in men with IDDM. PMID- 9366963 TI - Metabolite accumulation increases adenine nucleotide degradation and decreases glycogenolysis in ischaemic rat skeletal muscle. AB - Adenine nucleotides and glycogen are degraded in skeletal muscle during no-flow ischaemia. Past investigations have ascribed these metabolic changes to the severe energetic stress which arises with the removal of exogenous substrates (principally oxygen). We tested this hypothesis by measuring the high-energy phosphagen and glycogen contents of stimulated rat hindlimb muscles (1 twitch s 1) prior to and following 40 min of no-flow ischaemia or hypoxic perfusion without glucose (PaO2 = 4.6 +/- 0.1 torr, plasma glucose = 0.3 +/- 0.1 mmol L-1). Both experimental protocols eliminated exogenous substrate supply; however, the maintenance of flow during hypoxic perfusion ensured the removal of metabolic by products. A period of forty minutes of skeletal muscle ischaemia was characterized by reductions in the total adenine nucleotide pool, phosphocreatine and glycogen in the slow oxidative soleus, fast oxidative-glycolytic plantaris and the fast glycolytic white gastrocnemius. Compared to ischaemia, the total adenine nucleotide pool was higher (by 7.2-13.3 mumol g-1 dry wt) and the glycogen content lower (by 10.0-16.6 mumol g-1 dry wt) in skeletal muscle exposed to hypoxic perfusion without glucose. The ability of hypoxic perfusion to attenuate TAN degradation and augment glycogenolysis can be attributed to metabolic by-product removal. By limiting muscle lactate and PCO2 accumulation, hypoxic perfusion without glucose attenuates cellular acidification; this could in turn limit AMP deaminase activation and glycogen phosphorylase inhibition. We conclude that the ischaemia-induced alterations in adenine nucleotide and glycogen metabolism arise in response to the elimination of exogenous substrates and to the accumulation of metabolic by-products. PMID- 9366964 TI - Exogenous endothelin-1 causes peripheral insulin resistance in healthy humans. AB - In states of insulin resistance, increased plasma levels of endothelin-1 and a disturbed vascular reactivity have been reported. In order to investigate the effects of endothelin-1 on peripheral insulin sensitivity and the vasoactive interactions between insulin and endothelin-1, six healthy subjects were studied on two different occasions with the euglycaemic hyperinsulinaemic clamp technique combined with an intravenous infusion of either endothelin-1 (4 pmol kg-1 min-1) or 0.9% sodium chloride. During the endothelin-1 infusion, arterial plasma endothelin-1 levels rose 10-fold. The endothelin-1 infusion reduced insulin sensitivity as demonstrated by a 31 +/- 7% decrease in whole-body glucose uptake (P < 0.05) and a 26 +/- 11% fall in leg glucose uptake (P < 0.05) compared with the control protocol. During the state of hyperinsulinaemia, exogenous endothelin 1 increased mean arterial blood pressure by 8 +/- 1% (P < 0.05) and decreased splanchnic and renal blood flow by 30 +/- 6% (P < 0.001) and 20 +/- 4% (P < 0.001), respectively. However, the endothelin-1 infusion did not lower skeletal muscle blood flow measured as leg and forearm blood flow. In summary, exogenous endothelin-1 induced insulin resistance in healthy humans by reducing insulin dependent glucose uptake in skeletal muscle without decreasing skeletal muscle blood flow. Furthermore, endothelin-1 also preserved its vasoactive potency in the presence of hyperinsulinaemia. PMID- 9366965 TI - Salivary carbonic anhydrase VI concentration and its relation to basic characteristics of saliva in young men. AB - Two successive saliva samples were collected under strictly standardized conditions from 209 healthy, selected male soldiers prior to and after breakfast in the morning and were assayed for carbonic anhydrase (CA) VI concentrations using a specific time-resolved immunofluorometric assay. Salivary secretion rates, pH and buffer capacity pH values, and amylase activity levels were also determined. CA VI concentrations correlated positively to salivary secretion rates and amylase activity levels. By contrast, no significant correlation was seen between CA VI concentrations and pH or buffer capacity pH values, nor between amylase activity levels and salivary secretion rates, pH or buffer capacity pH values. The smokers had unaltered salivary secretion rates, CA VI and amylase activity levels, but lower salivary pH and buffer capacity pH values than the non-smokers. Present results suggest that salivary CA VI is not directly involved in the regulation of pH in saliva. PMID- 9366966 TI - BK channels in intact clonal rat pituitary cells are activated by physiological elevations of the cytosolic Ca2+ concentration at the normal resting potential. AB - Activation of large conductance Ca(2+)-activated K+ channels (BK channels) in intact clonal rat pituitary cells (GH4 cells) was investigated using the cell attached patch-clamp configuration. This method prevents loss of intracellular factors which might influence channel activity. BK channels are generally considered to be inactive at the resting membrane potential in excitable cells. However, at the resting potential (0 mV pipette potential), 40% of the cell attached patches displayed spontaneously active BK channels, which remained active even at 20 mV hyperpolarization. The peptide thyroliberin (TRH) elevates the cytosolic Ca2+ concentration ([Ca2+]i) in GH cells by IP3-induced release of Ca2+ from intracellular stores. This rise in [Ca2+]i occurs concomitantly with membrane hyperpolarization. TRH stimulation caused activation of BK channels in nine out of 30 silent cell-attached patches, and caused enhanced channel activity in seven out of 29 cell-attached patches containing spontaneously active BK channels. The Ca2+ ionophore ionomycin activated silent BK channels in three out of 10 cell-attached patches, and increased the activity of spontaneously active BK channels in seven out of 16 cell-attached patches. The pipette potential was clamped to 0 mV in all these experiments. We conclude that the BK channels in GH4 cells may be active at the resting membrane potential and more negative membrane potentials. The channels may also be activated further by physiological elevations of [Ca2+]i in the same potential range. Our results point towards new possible physiological roles for the BK channels in GH4 cells. This is in agreement with the emerging picture of BK channels highly sensitive to [Ca2+]i in a wide variety of cell types. PMID- 9366967 TI - Pressure-induced basilar membrane position shifts and the stimulus-evoked potentials in the low-frequency region of the guinea pig cochlea. AB - We have used the guinea pig isolated temporal bone preparation to investigate changes in the non-linear properties of the tone-evoked cochlear potentials during reversible step displacements of the basilar membrane towards either the scala tympani or the scala vestibuli. The position shifts were produced by changing the hydrostatic pressure in the scala tympani. The pressures involved were calculated from measurements of the fluid flow through the system, and the cochlear DC impedance calculated (1.5 x 10(11) kg m-4 s-1, n = 10). Confocal microscopic visualization of the organ of Corti showed that pressure increases in the scala tympani caused alterations of the position of the reticular lamina and stereocilia bundles. For low pressures, there was a sigmoidal relation between the DC pressure applied to the scala tympani (and thus the position shift of the organ of Corti) and the amplitude of the summating potential. The cochlear microphonic potential also showed a pronounced dependence on the applied pressure: pressure changes altered the amplitude of the fundamental as well as its harmonics. In addition, the sound pressure level at which the responses began to saturate was increased, implying a transition towards a linear behaviour. An increase of the phase lag of the cochlear microphonic potential was seen when the basilar membrane was shifted towards the scala vestibuli. We have also measured the intracochlear DC pressure using piezoresistive pressure transducers. The results are discussed in terms of changes in the non-linear properties of cochlear transduction. In addition, the implications of these results for the pathophysiology and diagnosis of Meniere's disease are discussed. PMID- 9366968 TI - Assessment of renal function by 51Cr-EDTA and endogenous creatinine clearances in the pig. AB - In anaesthetized pigs, clearances of 51Cr-EDTA (EDTA) and endogenous creatinine were compared with renal clearance of inulin measured during constant infusion after bolus injection. Creatinine was determined by enzymatic (Kodak Ektachem) as well as conventional (Jaffe) methods. In saline-loaded pigs, renal clearance of constantly infused EDTA was 97.0 +/- 6.7 mL min-1 and identical to the clearance of inulin (94.1 +/- 9.1 mL min-1). There was good agreement between individual clearances. The extraction fractions of the two markers were indistinguishable (0.26 +/- 0.02 and 0.28 +/- 0.03, respectively). In other experiments the clearance of EDTA calculated from the first 4 h of the time course of the plasma concentration after single injection was 64.4 +/- 3.7 mL min-1, correlating well with inulin clearance (63.0 +/- 1.2 mL min-1). When calculated only from the monoexponential phase of the disappearance curve ('slope clearance'), significantly higher results were obtained (+33%, P < 0.001). Renal clearance of EDTA after single injection was 7.5 +/- 1.5 mL min-1 (approximately 12%) lower than inulin clearance (P < 0.001). Values of creatinine clearances determined by the two analytical methods showed a poor agreement with inulin clearance. It is concluded that, in pigs, glomerular filtration rate may be estimated by the clearance of EDTA using constant infusion or single injection of EDTA and that the renal clearance of endogenous creatinine is a less useful a measure of GFR. PMID- 9366969 TI - Motivation and readiness for therapeutic community treatment among adolescents and adult substance abusers. AB - A growing body of research has demonstrated the importance of motivation and readiness among drug abusers in seeking, complying with, and remaining in treatment. To date, however, there is little research on these factors among adolescent substance abusers. The present study reports findings from a large scale investigation of motivation and readiness differences across adolescent (range = 14-18 years, n > 1000) and adult (range = 19-26 + years, n > 1400) admissions to residential therapeutic communities (TCs). Data were collected with an instrument assessing circumstances, motivation, readiness, and suitability for TC treatment (i.e., CMRS). Results showed that: (1) there is a significant positive linear relationship between CMRS scores and age; (2) the CMRS scores were the largest and most consistent predictors of short term retention across all age groups. Although confined to TC samples, the present findings support clinical observations that adolescent drug abusers are less motivated to change or ready for treatment than adults; and they confirm the importance of motivational and readiness factors in the treatment process, regardless of age. PMID- 9366970 TI - Injecting drug users who want treatment. AB - This study examined characteristics of injecting drug users (IDUs) who want treatment and the features that differentiate them from IDUs who do not want treatment. Data were collected as part of a community-based HIV prevention project in San Antonio, Texas. Interviews were administered to 1,100 IDUs between February 1993 and May 1995. Interview topics included sociodemographics, drug use history, current drug use, treatment history, injection-related HIV risk behavior, sexual behavior, and previous contact related to HIV prevention. Multiple logistic regression analysis identified four factors independently associated with wanting treatment in the multivariate model. These were: (1) 30 or more injections per month; (2) being eligible for methadone maintenance; (3) 2 or more previous treatment admissions; and (4) being recruited after the first year of the project. Implications of these findings are discussed. PMID- 9366971 TI - The early emergence of narcotic addict types. AB - Providing retrospective self-reports of their activities, perceptions, and experiences during their early adolescent years (ages 12 to 14), 255 narcotic addicts were classified into four distinct types on the basis of a clustering technique applied to risk factor information derived from five major descriptive domains: family; peer deviance; personal deviance; psychological status; and protective factors. Differentiations among the types largely involved the extent of early drug and other behavioral deviance and family dysfunction. The predictive utility of the typology was examined in terms of outcome over the first ten years of the addiction career, including age at first narcotic addiction, amount of time incarcerated, and percentage of time addicted while in the community. The implications of the typology for both substance abuse prevention and treatment are discussed. PMID- 9366972 TI - Treatment of early AIDS dementia in intravenous drug users: high versus low dose peptide T. AB - This placebo-controlled, double blind, cross-over study tested the efficacy of two different doses of Peptide T in the treatment of nine intravenous drug users with early AIDS dementia who were also receiving methadone and AZT. Subjects received Peptide T doses of either 15 or 1.5 mg daily for four weeks. Neuropsychological performance improved in four of five patients treated with the high dose, but at the lower dose, three of four patients showed no improvement on Peptide T when compared with placebo. When subjects who received the high dose were compared with those who received the low dose, a significant dose effect was found only during the active phase of the trial even after correction for differences in level of functioning at baseline. PMID- 9366973 TI - Crack users in east Harlem, New York and Philadelphia, Pennsylvania: HIV-related risk behaviors and predictors of serostatus. AB - Crack use has been associated with increased risk for HIV seropositivity. This study was undertaken to examine HIV-related risk behaviors among crack users in East Harlem, New York and Philadelphia, Pennsylvania, two northeastern communities which have reported extensive crack use. Crack users recruited in East Harlem (n = 1434) and Philadelphia (n = 694) were compared on demographics, drug and sex-related risk behaviors, health-related behaviors, and HIV serostatus. Many significant differences were found, and seropositivity was higher in the New York sample (25% vs. 11%, chi 2 = 36.28, p < .001). Being a recent drug injector was a significant predictors of seropositivity in both communities, and differences between communities were found in additional predictors of serostatus. Results suggest that tailored HIV interventions may be needed for different communities. In addition, aggregate data across communities, even those that may be in geographical proximity, may obfuscate differences important to incorporate in developing prevention/intervention efforts. PMID- 9366974 TI - A comparison of HIV-positive and HIV-negative crack users enrolled in a residential addiction treatment program. AB - This study compared 96 HIV-Positive (HIV+) and 357 HIV-Negative (HIV-) crack users who were participating in the same drug-free, residential treatment program. Comparisons were made on sociodemographic, health, criminal justice, psychosocial, and recovery motivation variables. As predicted, the HIV(+) participants were more apt than the HIV(-) participants to be female and recently homeless. Also as predicted, HIV(+) participants had poorer subjective health, had more convictions for various criminal offenses, and were less apt to acquire employment during treatment when compared to the HIV(-) participants. Contrary to prediction, HIV(+) participants reported more social support, were not less committed to abstinence or 12-step groups, and were not less apt to complete the treatment program in comparison to the HIV(-) participants. These results suggest that HIV(+) crack users can be successfully treated in a rigorous treatment program. Future research should examine post-treatment outcomes among HIV infected persons. PMID- 9366975 TI - Childhood abuse as a risk for partner abuse among women in methadone maintenance. AB - This study examines the relationship between childhood abuse and partner abuse among a sample of predominantly African-American and Hispanic women, who were patients in methadone clinics in Harlem and the South Bronx. A structured questionnaire addressing demographics, psychosocial and physical health characteristics, depression, childhood abuse, and domestic violence was administered to 151 women. Over half of the women (60%, n = 98) reported lifetime physical, life-threatening, or sexual abuse by a spouse or boyfriend. Multiple logistic regression analysis was used to assess the associations between childhood physical abuse and abuse by a spouse or boyfriend and between childhood sexual abuse and abuse by a spouse or boyfriend. After controlling for potential confounders, women who reported childhood physical abuse were almost nine times more likely to report having been abused by a spouse or boyfriend (OR = 8.74, CI, = 3.25 to 23.57). Women who reported childhood sexual abuse were almost four times more likely to report having been abused by a spouse or boyfriend (OR = 3.93, CI = 1.46 to 10.59). Depression and need for social support were significantly associated with partner abuse, while current heroin use was inversely associated with partner abuse. The high rate of domestic violence and the strong association between childhood and partner abuse found in this study suggest areas for intervention in chemical dependency among women. PMID- 9366976 TI - A comparison of family of origin factors between children of alcoholics and children of non-alcoholics in a longitudinal panel. AB - Secondary analysis of longitudinal panel data reveals minimal differences in family of origin factors between children of alcoholics (COAs) and children of non-alcoholics (non-COAs). From 220 subjects, 37 parents were identified as alcoholic. The COA subjects' retrospective reports about family of origin factors were compared to those of non-COAs. Contrary to the assertions of the COA clinical literature, few differences were found between the two groups. However, these differences are congruent with the findings of other panel studies which have investigated family of origin factors and adult outcome among COAs. PMID- 9366977 TI - Dexamethasone in the treatment of the alcohol withdrawal syndrome. AB - Pre-clinical studies and clinical case reports suggest that glucocorticoids may be efficacious in ameliorating the signs and symptoms of the alcohol withdrawal syndrome. In order to evaluate the efficacy of the glucocorticoid dexamethasone upon alcohol withdrawal, we administered 4 mg of dexamethasone intravenously to eight alcohol dependent men during withdrawal. Withdrawal severity, as determined by the amount of lorazepam required to ameliorate withdrawal symptoms, was compared to eight other withdrawing patients not administered dexamethasone. There was no significant difference between the two groups in the amount of lorazepam required to treat to withdrawal symptoms. This preliminary study suggests that dexamethasone, in doses expected to suppress hypothalmic-pituitary adrenal axis activation, is not efficacious in the treatment of alcohol withdrawal. PMID- 9366978 TI - The effects of anabolic steroids on driving performance as assessed by the Iowa Driver Simulator. AB - The effect of physiologic (100 mg/wk) and supraphysiologic (250 and 500 mg/wk) doses of testosterone cypionate (TC) on automobile driving were studied using the Iowa Driver Simulator. Six normal subject volunteers were studied off TC and on TC once steady-state concentrations were achieved after at least three weeks of dosing. Despite the administration of supraphysiologic testosterone doses, an increase in aggressive driving behavior was not detected. Likewise, corresponding psychometric testing using the Buss-Durkee Hostility Inventory to assess aggression was unable to detect any change in aggression in the test subjects. Although aggressive driving behavior may be increased by testosterone administration, the drug itself may not be responsible for these effects. Supraphysiologic doses greater than 500 mg/wk and a semi-controlled research environment may be necessary to produce this effect since case reports of AAS abuse causing altered driving behavior may be multifactorial in nature. PMID- 9366980 TI - Transplantation. PMID- 9366979 TI - GHB: a home brew. AB - Gamma-hydroxybutyric acid is an allegedly benign illicit substance that is gaining increasing recognition and attention among substance abusers and athletes. Alongside foreign-made brands, the compound is also easily available, at low cost because of the facility with which it can be produced in one's kitchen. Named by some "Nature's Quaalude" or sold as a health product, it is often used with a false sense of security as it may cause serious and disabling complications, as illustrated by this clinical vignette. PMID- 9366981 TI - Kidney transplantation. AB - The authors present a short overview on the history of clinical renal transplantation and an update of the results of renal transplantation today. Factors contributing to chronic renal allograft failure and immunotherapy-related exposure to malignant diseases complicating life after transplantation are discussed. PMID- 9366982 TI - Liver transplantation. PMID- 9366983 TI - Heart transplantation in Finland 1985-1995. AB - BACKGROUND AND AIMS: Since improved immunosuppression in the 1980's, heart transplantation is a well established procedure to treat patients with end-stage heart failure. The first heart transplantation in Finland was performed in 1985. Since then the activity has gradually increased to a level of about 25 annual transplants. The aim of this report is to sum up the clinical experience during the first 11 years. MATERIALS AND METHODS: From February 1985 till the end of 1995, 190 heart transplantations were performed in our institution. There were 176 males and 14 females ranging from 15 to 62 (mean 42.2) years of age. End stage preoperative cardiac disease was dilating cardiomyopathy in 108 cases, coronary artery disease in 65 cases, valvular disease in 12 cases and congenital heart disease in five cases. RESULTS: The 30-day hospital mortality was 29 out of 190 (15.2%). The actuarial survival was 77% at one year, 75% at two years and 73% at 10 years. The most common causes of death were rejection (11 cases), graft failure (11 cases), abdominal complications (six cases) and cytomegalovirus (CMV) infection (four cases). A total of 87 rejection episodes occurred in 53 patients consisting 28 per cent of patients. 44 rejections occurred within three months post transplantation. Significant infections were noted in 198 instances in 97 patients. These were of bacterial origin in 92, viral in 48, fungal in 12 and protozoal in 10 cases, and 36 such infections which responded to antibiotics favourably but in which the microbe remained unidentified. 138 infections (i.e. 80%) occurred within 6 months post transplantation. In viral infections cytomegalovirus (CMV) predominated (29 out of 48). The CMV infection was significantly milder in patients who were seropositive preoperatively than in preoperatively seronegative patients with seropositive donors. CMV infection was associated with increased risk of post-transplant coronary artery disease. Three years after transplantation some restoration of sympathetic nervous response was observed at orthostatic test in heart rate and blood pressure. CONCLUSIONS: It can be concluded that 1) if a patient survives the three immediate postoperative months, his prognosis is good for the forthcoming years, 2) clinically significant rejections occur in less than one third of the patients, 3) cytomegalovirus is the most harmful agent post transplantation and a risk factor for post-transplant coronary artery disease and that 4) some restoration of sympathetic nervous control of the heart occurs within three years after transplantation. PMID- 9366985 TI - Bone marrow transplantation. PMID- 9366986 TI - Organ transplantation in children. PMID- 9366984 TI - En bloc heart and lung transplantation in Finland 1988-1996. AB - The purpose of the study was to review the first clinical experience in combined heart-lung transplantation in our institution. MATERIAL: From June 1988 to December 1996 15 en bloc heart and lung transplantations were performed. There were nine men and six women, aged 17-61 (mean 42.3) years. The indications for operation were primary pulmonary hypertension with right heart failure in five, Eisenmenger's syndrome in five, pulmonary embolism and right heart failure in three and emphysema with right heart failure in two cases. RESULTS: The hospital (30 day) mortality was four patients (26.6%). The causes of mortality were graft failure in two cases, infection and bleeding after transbronchial biopsy in one case and sepsis and aspergillosis in one case. Postoperative complications included eight cytomegalovirus (CMV), two Pneumocystis Carinii, five bacterial and five fungal (one Aspergillus and four Candida) infections. Rejection episodes (of the lungs) occurred in four patients (in 27%). During the follow-up to four years two patients developed diabetes mellitus (insulin therapy), one patient renal failure (dialysis), two patients tracheal stricture (laser resection), one patient fracture of the spine and one patient epilepsy. One patient died from prolonged CMV infection and chronic rejection eight months postoperatively. Four patients underwent bronchial artery revascularization (two with the internal thoracic artery and two with a vein graft). This was followed by improved airway healing and resistance towards infections. After a follow-up to four years 10 patients out of 15 (66.7%) were living an active life. CONCLUSION: Combined heart lung transplantation offers a good mid-term outcome for patients with end-stage cardiopulmonary disease. The results compare favourably with the corresponding international statistics. PMID- 9366987 TI - Pancreatic islet transplantation. AB - This article gives a short description of the status of islet transplantation in clinical practice today. Islet transplantation is still experimental and the results in humans are poor compared to the results of organ transplantation in general. Collaboration in the EU supported multinational study "Treatment of diabetes by islet cell transplantation" is reported. PMID- 9366988 TI - Vascularised pancreas transplantation. PMID- 9366989 TI - Intestinal transplantation. AB - In contrast to other solid organ transplantations slow progress has been seen in introducing intestinal transplantation (IT) from an experimental level to clinical practice. In nine years less than 200 transplantations have been performed worldwide with a three-years, survival of approximately 40%. The main problem of IT is immunological. Large amounts of lymphatic tissues transplanted along with the intestinal graft increase the risk of acute rejection and necessitate high doses of immunosuppressive regimens liable of inducing serious side-effects. The immunocompromized recipient is vulnerable to various infections, particularly cytomegalovirus (CMV) enteritis of the graft. However, improved results are expected after introducing modern potent immunosuppressive drugs such as combination of tacrolimus and mycophenolic acid. Emphasized antiviral prophylaxis and treatment, improved preservation and prevention of ischaemia reperfusion injury are other means presently available to obtain better results after intestinal transplantation in the near future. Intestinal transplantation is becoming the treatment of choice in intestinal failure when total parenteral nutrition (TPN) fails for one reason or an other. PMID- 9366990 TI - New trends in maintenance immunosuppression. AB - Maintenance immunosuppression in solid organ transplantation has been restricted to three drugs for many years, corticosteroids, azathioprine and cyclosporine. There has been need for more selective drugs with better ratio of efficacy to side effects. During the last decade a variety of new immunosuppressive agents has been under development and some of them are now at hand. PMID- 9366991 TI - MHC genes and histocompatibility. A review. PMID- 9366992 TI - Organ procurement in Finland. PMID- 9366993 TI - Organ exchange in the Nordic countries. AB - Scandiatransplant is an organ exchange organisation founded in 1969. It serves a population of 23 million inhabitants in the five Nordic countries; Iceland, Norway, Sweden, Finland and Denmark. Scandiatransplant maintains a common central waiting list for all Nordic patients waiting for necro-organ transplantation. The waiting lists are maintained on a central computer by each of the eleven transplant centres in the organisation. The number of necro-organ donors in Scandiatransplant is about 340-375 yearly, corresponding to 15-16 donors per million population (PMP) per year. Since the foundation, a total of 14,500 necro kidney transplants have been performed, and the number of transplants with extrarenal organs is steadily increasing. Presently, about 7-8 liver transplants PMP are being performed, and the heart transplant activity amounts to about 5 PMP. The supreme authority of Scandiatransplant is the Council of Representatives, in which each transplant centre is represented by one or more professionals who are clinically active in organ transplantation. The responsibility for day-to-day operations lies with the Board which has one member appointed by each of the five Nordic countries and a chairman elected by the Council. The activities of Scandiatransplant are financed exclusively by the participating centres. PMID- 9366994 TI - Xenotransplantation: facts and fiction. AB - Xenotransplantation will certainly solve the problem of the allogeneic organ shortage if long-term organ function can be achieved. Acceptance or rejection of the grafts depends not only on immunological mechanisms but, as already recognized in chronic rejection (i.e. transplant atherosclerosis), on many other biochemical, physiological, and even morphological characteristics including inflammatory events originating from infections. The way in which signals in the form of hormones, neurotransmitters, enzymes and growth factors are translated in xenogeneic systems has not received adequate attention, if any at all. Central questions still to be answered are: How many xenogeneic hormonal and enzymatical interactions are possible? Are they able to maintain the metabolism in a foreign organ or body and for how long? In addition, transport molecules, the most important of which is albumin, must be considered when trying to achieve long term survival time using organs from a widely divergent species. Large quantities of foreign proteins, mediators and enzymes are released into the circulation when, for example, xenogeneic livers or other organs suffer from HXAR. The function of the liberated enzymes, hormones and inhibitors is far from being understood or even investigated. The amount of potassium released from a deteriorating xenogeneic liver is able to mimic a sometimes lethal cardioplegic solution. The first data coming from intra-vital microscopy herald that adhesion molecules, the newest but not last in the line of trouble-shooters, play a major role in microcirculation together with interleukins and eicosanoids (32). These adhesion molecules may, as a falsely activated system or as an incompatible system, be unable to protect the endothelial cells from the attack, adhesion and migration of white blood cells. Even when transgenic animals or other imaginative manipulations lead to the acceptance of any type of xenograft, it has to be established how far, and for how long, the products of the xenograft will be able to interact in the multifactorial orchestra. Despite this rather careful if not pessimistic appraisal, xenotransplantation has to be investigated vigorously even though the short-term outlook does not seem to be promising. PMID- 9366995 TI - Effects of drugs on clinical laboratory tests. PMID- 9366996 TI - Advances in plasma protein standardization. PMID- 9366997 TI - Clinical application of intact parathyroid hormone assays. PMID- 9366998 TI - Vitamin analysis. PMID- 9366999 TI - Hyperproinsulinaemia in acromegaly: evidence for abnormal pancreatic beta-cell function? AB - We investigated whether pancreatic beta-cell dysfunction has a role in the pathogenesis of glucose intolerance in acromegaly by comparing plasma intact proinsulin, immunoreactive insulin, C-peptide and glucose concentrations during a 75 g oral glucose load in six patients with active acromegaly and eight healthy volunteers. Only acromegalic patients with normal glucose tolerance were studied. Glucose concentrations were similar in acromegalic patients and controls. Acromegalic patients had higher fasting insulin (P < 0.005) and fasting C-peptide (P < 0.005) concentrations than controls. Although fasting proinsulin levels were higher in acromegalic patients than controls, this did not achieve statistical significance. Integrated insulin (P < 0.05), C-peptide (P < 0.05) and proinsulin (P < 0.005) concentrations were greater in acromegalic patients than control subjects. Integrated (P < 0.05) proinsulin:insulin molar ratios were higher in acromegalic patients than controls. Fasting and integrated insulin:C-peptide molar ratios were similar in acromegalic patients and controls. These results indicate that hyperproinsulinaemia contributes to the hyperinsulinaemia which characterizes active acromegaly. The disproportionate hyperproinsulinaemia in acromegaly suggests that prolonged and excessive growth hormone secretion may result in pancreatic beta-cell dysfunction which may predispose acromegalic subjects to glucose intolerance. PMID- 9367000 TI - Measurement of plasma 1,25 dihydroxyvitamin D using a novel immunoextraction technique and immunoassay with iodine labelled vitamin D tracer. AB - We evaluated a novel assay for the measurement of 1,25 dihydroxyvitamin D (1,25 (OH)2D). Immunoextraction of 1,25(OH)2D is performed using a mini column containing a solid-phase monoclonal antibody followed by radioimmunoassay (RIA) using an 125I-labelled 1,25(OH)2D derivative tracer and Sac-cell separation. The mean recovery of 1,25(OH)2D3 was 101%, linearity was excellent, inter- and intra assay coefficients of variation were 9, 8 and 13% and 11, 10 and 14% at low, medium and high concentrations of 1,25 (OH)2D3, respectively. The cross reactivity of vitamin D metabolites was < 0.0015% for 25-hydroxyvitamin D3, 24, 25 dihydroxyvitamin D3 and dihydrotachysterol and 0.54% for 1 alpha calcidol. 1,25 dihydroxyvitamin D2 cross-reactivity was 79%. The detection limit of the assay was 5 pmol/L. Comparison with a commercial radio receptor assay (RRA) and an in-house RIA gave regression equations of y = 0.94x + 11.8 (r = 0.98) and y = 0.91x-1.7 (r = 0.95), respectively, with no major discrepancies between the methods in all patient groups studied. Plasma concentrations of 1,25(OH)2D obtained with the assay were as follows: normal, unsupplemented subjects: mean 88, range 48-155 pmol/L, n = 68, patients with chronic renal failure: mean 11, range 3-36 pmol/L, n = 27, primary hyperparathyroidism: mean 198, range 130-299 pmol/L, n = 23, Paget's disease: mean 92, range 42-149 pmol/L, n = 24, osteomalacia: mean 43, range 27-61 pmol/L, n = 9. A minimum sample volume of 300 microL is required, the hands-on time is significantly less than other commercial assays and the measuring procedure is gamma counting rather than scintillation counting. The assay offers several advantages over previous methods and should allow more laboratories to offer measurement of 1,25(OH)2D as part of their repertoire. PMID- 9367001 TI - Poor glycaemic control is associated with reduced serum free radical scavenging (antioxidant) activity in non-insulin-dependent diabetes mellitus. AB - The diabetic patient is at significantly increased risk of developing vascular disease. Its aetiology may involve oxidative damage by free radicals and protection against such damage can be offered by radical-scavenging antioxidants. We investigated whether there was a relationship between glycaemic control as assessed by measurement of glycated haemoglobin (HbA1c) and serum antioxidant status in a population of 118 diabetic outpatients with either insulin-dependent or non-insulin-dependent diabetes. Amongst patients with non-insulin-dependent diabetes mellitus there was a significant inverse correlation between levels of glycated haemoglobin and total free radical scavenging activity (r = -0.456, P < 0.0001). This association resulted primarily because of a similar correlation with uric acid (r = -0.421, P = 0.0003). There was also a weak inverse correlation with vitamin A but no significant association with vitamin C or vitamin E levels. There were no significant associations found amongst the patients with insulin-dependent diabetes. These results indicate that poor diabetic control is associated with reduced serum free radical scavenging (antioxidant) activity in non-insulin-dependent diabetes mellitus. By implication improved glycaemic control may preserve serum antioxidant status in diabetes. PMID- 9367002 TI - Vanadium-mediated oxidation of NADH is enhanced by aluminium and inhibited by vitamin E and some copper (II) complexes. AB - The effect of aluminium on vanadium-mediated oxidation of NADH was examined. The oxidation of NADH was enhanced in the presence of aluminium. The effect was concentration dependent. Vitamin E and copper (II) complexes with superoxide dismutase (SOD)-like activities containing isobutyric acid hydrazine were tested for their effect on the vanadium-mediated oxidation of NADH. The stimulatory effect of aluminium was decreased upon addition of different concentrations of vitamin E and copper (II) complexes. These results indicate that the biological toxicity of aluminium may be attributed to its enhancement of the production of superoxide radicals (O2.-) in association with the accumulation of other trace elements such as vanadium. PMID- 9367003 TI - Changes in serum osteocalcin levels in the follow-up of kidney transplantation. AB - Serum osteocalcin, total alkaline phosphatase, intact parathyroid hormone (PTH), creatinine, calcium, and phosphate were determined in 23 kidney cadaveric allograft recipients, immediately before and 0.5, 1, 3 and 6 months after surgery. Immunosuppressive treatment was based on low doses of corticosteroids and cyclosporin combined with antilymphoblast globulin. The decrease in serum creatinine was accompanied by falling PTH concentrations. Serum osteocalcin levels were higher than normal before kidney transplantation and diminished at 0.5 and 1 month after surgery. Significant increases in serum osteocalcin concentrations were observed 3 and 6 months after kidney transplantation with a significant correlation with alkaline phosphatase levels. The increase in serum osteocalcin levels observed in our transplanted patients is not related with a parallel increase in serum creatinine levels nor with an increment in PTH levels; it seems to reflect an increase in the osteoblastic activity, which is not altered by steroid therapy. PMID- 9367004 TI - Biochemical effect of antioxidants on lipids and liver function in experimentally induced liver damage. AB - Recent studies demonstrated the role of antioxidants in preventing organ damage caused by free radicals. The present study was conducted to find out the modulatory effect of some antioxidants on lipid patterns in experimentally induced liver damage. Rats chronically intoxicated with carbon tetrachloride (CCl4) were used as a model of liver injury terminating with fibrosis or cirrhosis. One hundred and sixty six albino rats were classified into five groups: one served as a control group; the second was subjected to oral administration of CCl4 (200 microL/100 g body weight) twice a week; the other three groups, in addition to CCl4, received oral doses of silymarin (30 mg/kg), vitamin E (200 IU/kg) and vitamin C (50 mg/kg) respectively. At the end of the experiment, the animals were killed, blood was collected and liver was taken for histopathological examination. Liver function tests, disturbed by CCl4 were significantly modulated by antioxidants, and histopathological examination showed that antioxidants ameliorated the necrotic and fibrotic changes caused by CCl4. Treatment with antioxidants was also shown to modulate the toxic effect of CCl4 on the lipid profile and malondialdehyde content. Administration of antioxidants could play an important role in prophylaxis against lipid peroxidation and consequently liver fibrosis caused by free radicals. PMID- 9367005 TI - Difficulties in evaluating urinalysis following combined pancreas-kidney transplantation. AB - Combined pancreas-kidney transplantation has been introduced in the treatment of patients with type 1 diabetes and renal failure 20 years ago. By 1985 374 combined pancreas-kidney transplantations had been reported to the International Pancreas Transplant Registries. Surgical drainage of the transplanted exocrine pancreas into the urinary bladder solves most of the postoperative problems encountered with the exocrine secretions. Furthermore, monitoring of pancreatic enzyme (amylase) activity in urine has been shown to be useful in diagnosis of rejection of the pancreatic graft. However, little attention has been paid to the biochemical consequences of high activities of proteolytic pancreatic enzymes on the determination of urinary proteins. The present case illustrates the difficulties in interpreting proteinuria in patients with combined pancreas-renal transplant with pancreaticocystostomia. In the propositus, interpretation of the urinary protein electrophoresis is hampered by the presence of pancreatic juice proteins and peptides originating from digestion of proteins by activated pancreatic enzymes. Results of immunochemically determined marker proteins ([micro]albumin, transferrin, beta 2-microglobulin) are unreliable due to digestion by pancreatic enzymes. PMID- 9367006 TI - Urinary excretion of albumin and retinol binding protein in systemic lupus erythematosus. AB - We have measured the urinary excretion of total protein, albumin and retinol binding protein (RBP) in random urine specimens obtained from 40 female patients with systemic lupus erythematosus (SLE). Thirty-three of these patients had no clinical evidence of any renal impairment (non-renal SLE); seven had overt renal disease (renal SLE). RBP:creatinine ratios were significantly higher in non-renal SLE patients compared with female controls (P = 0.002). There was no significant difference between urine total protein concentrations, albumin:creatinine or total protein:creatinine ratios in non-renal SLE patients when compared with controls, despite approximately 20% of these patients having elevated excretion of total protein or albumin. All seven renal SLE patients had elevated albumin:creatinine ratios but only four of them had an increased RBP:creatinine ratio. Of 29 non-renal SLE patients who had urinary total protein concentrations below 0.2 g/L, (i.e. approximating to a negative protein dipstick), 14 had increases in either albumin or RBP:creatinine ratios. Only two patients had increases in both. In the absence of clinical evidence of renal disease, increases in urinary albumin or RBP excretion could indicate subclinical nephropathy and measurements may have a role in the early diagnosis and subsequent monitoring of renal disease in SLE. PMID- 9367007 TI - Atypicality or specific screen: which is better at detecting non-Down's chromosomal anomalies? AB - I evaluated the value of adding a trisomy 18 screen to routine Down's screening and compared it with the benefits of atypicality screening. I studied 5080 unaffected pregnancies, 144 Down's syndrome and 190 non-Down's syndrome chromosome abnormalities (20 trisomy 13; 79 trisomy 18; 20 Turner's syndrome; 29 other sex chromosome abnormalities; 8 triploidy; and 34 miscellaneous). Using a one in 250 cut off, the Down's screen gave a screen positive rate of 4.07%; addition of atypicality without a trisomy 18 screen gave an extra 0.9% screen positives; trisomy 18 screening without atypicality gave an extra 0.51% screen positives; and atypicality screening after trisomy 18 screening gave 0.52% screen positives. Total screen positive rates were: Down's screening only, 4.07%; Down's screening + atypicality, 4.97%; Down's screening + trisomy 18 screen, 4.58%; Down's screening + trisomy 18 screen + atypicality, 5.09%. The detection rate for Down's syndrome using a one in 250 cut off was 58.9% and with addition of trisomy 18 and atypicality screening this increased to 59.3%, indicating that the extra screens add little to detection of Down's syndrome. For the other chromosomal abnormalities, Down's screening alone detected 22.6% of cases overall and addition of trisomy 18 and atypicality screening increased this to 49%. Examination of the marginal benefits of the extra screening tests revealed that the trisomy 18 screen was better at detecting chromosomal abnormalities than the Down's screen and that it would, therefore, be worthwhile adding this to all screening programs. Atypicality proved to be much less effective and it is suggested that this screen should only be applied in the early days of a screening program until sufficient data is available to design specific screens. PMID- 9367008 TI - Identification of apo(a) phenotypes in a Korean population using a standardized nomenclature system based on the number of kringle IV repeats. AB - We determined serum lipoprotein(a) [Lp(a)] concentrations and apolipoprotein(a) [apo(a)] phenotypes in 193 healthy Koreans. We analysed the apo(a) phenotypes by a simplified sodium dodecyl sulphate-polyacrylamide gel electrophoresis method and classified apo(a) isoforms objectively using an apo(a) phenotype standard with a known number of kringle IV repeats. The frequency distribution of Lp(a) levels showed marked positive skew with a mean of 0.143 g/L and a median of 0.052 g/L. Of the 193 subjects tested, no bands were detected in three, and single- and double-band phenotypes were observed in 103 and 87, respectively. Among the Koreans, the most frequent phenotype was S5(39.4%), followed by S4S5(17.1%), S5S5(14.0%), S4(11.4%), S3S5(5.2%), and the remaining phenotypes (13.0%). The calculated apo(a) allele frequencies were LpF, 0.003; LpS1, 0.013; LpS2, 0.010; LpS3, 0.048; LpS4, 0.198; LpS5, 0.563 and Lp0, 0.165. We found that the serum Lp(a) concentration in Koreans was similar to that of Caucasians, but the apo(a) allele size distribution was shifted toward higher molecular weights. PMID- 9367009 TI - The total antioxidant capacity of human serum measured using enhanced chemiluminescence is almost completely accounted for by urate. PMID- 9367010 TI - Changes in serum bone-specific alkaline phosphatase following tibial fracture. PMID- 9367011 TI - What is the best formula for predicting osmolar gap? PMID- 9367012 TI - Pseudohypercalcaemia in two patients with IgM paraproteinaemia. PMID- 9367013 TI - Hyperlipidaemia in association with benign paraproteinaemia. PMID- 9367014 TI - Lens lipid peroxides in diabetic cataract. PMID- 9367015 TI - Screening for macroprolactinaemia. PMID- 9367016 TI - Screening for macroprolactinaemia. PMID- 9367017 TI - The society at a crossroads: milestones and imperatives for cancer clinical trials. PMID- 9367018 TI - Local rotational flaps for breast conservation therapy as an alternative to mastectomy. AB - BACKGROUND: An anticipated poor cosmetic result has traditionally been deemed a relative contraindication for breast conservation therapy (BCT). We sought to determine whether a local rotational flap could achieve satisfactory cosmesis in patients who were anticipated to have a poor cosmetic result following standard segmental mastectomy but who nevertheless desired BCT. METHODS: Within the past 3 years, nine patients were treated with BCT using local rotational flap techniques. Their records were reviewed for patient characteristics, pre- and postoperative treatment, disease-free status, and patient satisfaction with cosmesis. RESULTS: The cosmetic outcome following a segmental mastectomy was anticipated to be unacceptable due to the following features: a large previous biopsy cavity with unknown or positive margins (three patients); initial large primary tumors with unknown extent of residual disease following induction chemotherapy (five patients); and pre-existing poor cosmesis (one patient). One patient had refused modified radical mastectomy and had satellitosis from inadequately treated primary tumor (excisional biopsy with positive margins and no further therapy). The median initial tumor size was 2.7 cm (range, 1.5 cm to 5.0 cm). Final resection margins were negative in all patients. Postoperative radiotherapy was given in seven patients; one patient did not receive radiotherapy because of a pre-lupus condition and one did not require radiotherapy because her pathologic diagnosis was Paget's disease without an invasive component. Cosmesis was judged to be good to excellent by eight of nine patients. The patient who refused mastectomy was dissatisfied with cosmesis because of mild asymmetry. With a median follow-up of 24 months, only one patient has developed a local recurrence. CONCLUSION: Local rotational flaps composed of adjacent breast tissue are an acceptable method of achieving satisfactory cosmesis in selected patients who desire BCT. PMID- 9367019 TI - Optimal surgical treatment of invasive lobular carcinoma of the breast. AB - BACKGROUND: The roles of breast conservation and surgical evaluation of the contralateral breast in the treatment of lobular carcinoma of the breast remain unclear. The aim of this study was to compare local recurrence, 5-year survival, and incidence of contralateral breast cancer in women with lobular carcinoma to that in women with infiltrating ductal carcinoma. METHODS: Women with infiltrating ductal carcinoma (IDC) and invasive lobular breast carcinoma (ILC) diagnosed during the years 1984 to 1994 were identified through a statewide tumor registry. The women were divided into groups based on their histology and treatment (breast conservation or modified radical mastectomy). The incidences of contralateral breast cancer, local recurrence, and 5-year survival were compared within each histologic group and treatment category. RESULTS: During the period 1984 to 1994, 4886 women were diagnosed with invasive lobular or ductal breast carcinoma. Of these, 316 (6.5%) had infiltrating lobular cancer. The 5-year survival rates were 68% and 71% for ILC and IDC, respectively (p = 0.5). The local recurrence rates were 2.8% and 4.3% for ILC treated with lumpectomy and axillary nodal dissection (LAND) and modified radical mastectomy (MRM), respectively, which were not significantly different from that obtained with IDC (LAND = 2.5%, MRM = 2.1%). The incidence of contralateral breast cancer during the period was 6.6% and 6.5% for ILC and IDC, respectively. CONCLUSIONS: Invasive lobular carcinoma can be safely treated with breast conservation with no difference in local recurrence or survival. In the absence of a suspicious finding on clinical or radiologic examination, routine contralateral breast intervention is not recommended. PMID- 9367020 TI - Prediction of recurrence and survival by post-resection CA 19-9 values in patients with adenocarcinoma of the pancreas. AB - BACKGROUND: CA 19-9 levels are useful for the diagnosis of patients with pancreatic adenocarcinoma. However, interest has recently turned toward its use as a prognostic indicator. The purpose of this study is to determine whether postoperative CA 19-9 levels predict disease-free survival (DFS) and median survival (MS) in patients after resection. METHODS: Between 1988 and 1996, 40 patients underwent resection for pancreatic adenocarcinoma and were evaluated with postoperative CA 19-9 assays. Eight patients had low preoperative levels of CA 19-9 (< 2) and were excluded. RESULTS: CA 19-9 levels are good predictors of DFS and MS. Patients whose postoperative CA 19-9 values normalized by 3 to 6 months (< 37 U/ml) had longer DFS (24 vs. 10 months, p < 0.04) and MS (34 vs. 13 months, p < 0.04). Patients with postoperative CA 19-9 values less than 180 U/ml at 1 to 3 months had a similar DFS (19 vs. 5 months, p < 0.0009) and MS (34 vs. 13 months, p < 0.0001) compared to patients with normal values at 3 to 6 months. CONCLUSIONS: Postoperative measurements of CA 19-9 were the best predictors of DFS and MS. Values < 180 U/ml at 3 months were as predictive as normal values by 3 to 6 months postoperatively. Consequently, CA 19-9 levels should be obtained for use as a stratification parameter in phase III trials. PMID- 9367021 TI - Correlation of lipid content and composition with liposarcoma histology and grade. AB - BACKGROUND: The determination of sarcoma grade, histologic type, and differentiation is often pathologist dependent and requires considerable expertise. METHODS: Lipid content and composition was analyzed in ex vivo fat, lipoma, and liposarcoma tissue samples using proton-decoupled 13C nuclear magnetic resonance (13C-NMR) spectroscopy and correlated with the histologic type and grade of liposarcoma. RESULTS: The well-differentiated liposarcomas were found to have threefold increases in fatty acyl chain content compared with benign lipomas. The fatty acyl chain content of the dedifferentiated and pleomorphic liposarcomas was 1% of that found in lipoma and < 0.2% of that found in well-differentiated liposarcoma. The 2.1- to 2.8-fold increase in the degree of polyunsaturation in the dedifferentiated and pleomorphic liposarcomas compared with well-differentiated liposarcoma could largely be accounted for by the 2.3 fold increase in the percentage of fatty acyl chains of lipid containing linoleic acid. The dedifferentiated and pleomorphic liposarcomas contained both free fatty acids and phospholipids that were not NMR detectable in normal fat, lipoma, and well-differentiated liposarcoma. CONCLUSION: Ex vivo 13C-NMR spectroscopy may be used to distinguish lipoma from well-differentiated, dedifferentiated, and pleomorphic liposarcoma based on changes in lipid and phospholipid metabolite profiles and may serve as adjunct to conventional light microscopy for the determination of liposarcoma histologic type and thus grade. PMID- 9367022 TI - Women's use of resources in decision-making for early-stage breast cancer: results of a community-based survey. AB - BACKGROUND: The majority of women with stage I/II breast cancer may choose between mastectomy and breast-conserving therapy (BCT). A survey was designed to examine the resources women used in making this decision. METHODS: From 1990 to 1994, 261 patients were diagnosed with or treated for stage I/II breast cancer at Washington Hospital (Fremont, CA). One-hundred seventy-six surviving patients received a questionnaire asking them to anonymously rank various medical and nonmedical persons, audio and visual materials, and decision criteria on a 5 point scale with regard to their influence on that individual's choice to undergo BCT or mastectomy. The BCT and mastectomy groups were similar demographically; approximately 50% were college-educated. Statistical significance of the difference in means between groups was assessed with the t test. The response rate to the survey was 65%. RESULTS: The average survey ranking was > 1.0 for the following: surgeon (4.5), primary care physician (2.8), spouse (2.4), radiation oncologist (1.7), medical oncologist (1.5), American Cancer Society brochure (1.4), and children (1.2). The ranking of children (p = 0.08), friends (p = 0.08), parents (p = 0.09), and spouse (p = 0.13) was higher in the mastectomy group; the ranking of the radiation oncologist (p = 0.001) and ACS brochure (p = 0.03) was higher in the BCT group. The majority of patients consulted only with the surgeon (96%), primary care physician (64%), and spouse (55% overall, 75% among married patients) before making a treatment choice. Decision criteria were ranked as follows: chance for cure (4.5), physician recommendation (3.7), potential side effects (1.7), cosmetic appearance (1.3), sexual attractiveness (1.1), treatment convenience (1.0), and desire to avoid mastectomy (1.5). Desire to avoid mastectomy was higher in the BCT group (p < 0.0001); ranking of chance for cure was higher in the mastectomy group (p = 0.12). Overall satisfaction was higher in the BCT group; 87% of these patients were "very satisfied" with their decision versus 68% for the mastectomy group (p = 0.005). Review of the admitting records for 125 patients treated with mastectomy indicated that 46% had clear medical or personal contra-indications to BCT, but that the remainder might have benefitted from specialty consultation. CONCLUSIONS: The surgeon's recommendation and the patient's perception of chance for cure were the most influential factors affecting treatment decision. There was a limited use of specialty consultation or written and audiovisual materials in this educated patient population. The survey results suggest potential areas of intervention to improve rates of BCT, namely use of up-front multidisciplinary evaluation, further education of primary care physicians, and greater attention to concerns of family members. PMID- 9367023 TI - Pathologic findings at the time of nephrectomy for renal mass. AB - BACKGROUND: Ultrasound (US) and computed tomography (CT) have improved the diagnosis of solid renal masses. Nevertheless, some patients still undergo exploration for a presumptive diagnosis of renal cell carcinoma (RCC) and are found to have other pathology. We report a contemporary series of non-RCC renal masses (both incidental and symptomatic) among nephrectomies performed for suspected RCC. MATERIALS AND METHODS: All nephrectomies performed by the Urology Service at the Memorial Sloan-Kettering Cancer Center from July of 1989 through July of 1996 for a parenchymal renal mass were reviewed, and patients without a final diagnosis of RCC were identified. Cases were excluded if RCC was not suspected preoperatively. Presentation, preoperative radiographic evaluation, type of operation, and pathologic features were assessed. RESULTS: Of the 636 nephrectomies performed, 108 patients (16.9%) had a diagnosis other than RCC. CONCLUSIONS: Of patients undergoing nephrectomy for renal masses, 16.9% have other pathologic diagnoses. Sixty-six percent of these non-RCC masses are discovered incidentally, and the majority are treated with radical nephrectomy. Preoperative radiographic evaluation reflects both clinical presentation, with IVP used to evaluate symptomatic tumors, and diagnostic uncertainty, with multiple modalities used to evaluate cystic lesions. This information has important implications for preoperative counseling and surgical planning. PMID- 9367024 TI - Plantar flap reconstruction for acral lentiginous melanoma. AB - BACKGROUND: Acral lentiginous melanoma continues to be difficult to diagnose despite an overall trend toward early identification of smaller and thin lesions. The insidious nature of this lesion often precludes primary closure of the surgical defect once it is excised, adding to the reconstructive complexity. Local flaps on the plantar foot offer an option for reconstruction when the defect is of intermediate size. METHODS: Eight patients (5 men and 3 women, with an average age of 58 years) who underwent plantar flap reconstruction for defects isolated to the weight-bearing heel were retrospectively reviewed. RESULTS: The average depth of the melanoma was 2.82 mm. Surgical margins were 2 cm or less in seven of the eight patients. Partial flap necrosis occurred in one patient, and loss of part or all of the skin grafts was noted in two patients. Currently five patients are alive with no evidence of disease. CONCLUSION: The plantar flap can provide local well-vascularized tissue for weight-bearing areas where skin grafting alone may not be appropriate. Coverage of these areas with well-padded flaps led to ambulation in all of the patients studied. We believe this flap offers durable coverage for medium-sized defects in acral lentiginous melanoma. PMID- 9367025 TI - Cytokines as an adjuvant to tumor vaccines: efficacy of local methods of delivery. AB - BACKGROUND: We examined alternative methods of delivering cytokines as an adjunct for priming lymph node (LN) cells draining sites of vaccine inoculation for the purpose of generating immune cells for adoptive immunotherapy. METHODS: Using syngeneic murine tumors we examined the ability of IL-2, IL-4, or GM-CSF delivered locally to a site of tumor inoculum to induce antitumor reactive draining LN cells. Mice were inoculated subcutaneously with tumor cells transduced to secrete cytokine; tumor cells admixed with fibroblasts transduced to secrete cytokine; or intralesional inoculation of cytokine in established tumor to induce sensitized LN cells capable of mediating tumor regression in adoptive transfer. RESULTS: Both IL-4 and GM-CSF cytokines were effective in enhancing the antitumor reactivity of vaccine-primed LN cells compared to IL-2, which was ineffective. The local delivery of GM-CSF by autocrine or paracrine secretion of genetically engineered cells, as well as direct intratumoral delivery was capable of upregulating LN sensitization compared to systemic administration, which did not. CONCLUSIONS: The local delivery of GM-CSF as an adjuvant for tumor vaccination can be accomplished by various methods, including direct injection, which avoids the need for gene transfer. PMID- 9367027 TI - Quality of life as defined by orthopedic oncology patients. AB - BACKGROUND: Quality of life (QOL), not just survival, is central to outcomes analysis in musculoskeletal oncology. However, little information exists about the patients' definition of what constitutes QOL. METHODS: Self-administered outcomes questionnaires were given to 201 surgically treated patients with lower extremity tumors. Of these patients, 192 (137 with malignant tumors, 55 with benign tumors) provided a written definition of QOL. Their responses were independently collated and matched with clinical information. RESULTS: For most patients (153, or 80%) the definition of QOL encompassed several attributes. A consistent combination of four major attributes was used in the QOL definition by 44 (32%) of the malignant cases and 19 (35%) of the benign cases. Differences in responses between men and women were idiosyncratic and more common in the benign group. Good family relations and good health were equally important to men and women. Responses varied by patient age. Older patients valued self-sufficiency and freedom from pain, whereas younger patients emphasized happiness, trust in God or church, achieving goals and being successful, and love. Those whose surgery was less extensive cited good family relations, the ability to function physically and emotionally, and having a good job or work. CONCLUSION: The variation in patients' perspectives and definitions of quality of life must be taken into account when assessing QOL in musculoskeletal oncology patients. Patients often emphasize concerns that are not adequately addressed by current outcomes-measures in orthopedics and general oncology. PMID- 9367026 TI - Prospective cohort study of neoadjuvant treatment in conservative surgery of soft tissue sarcomas. AB - BACKGROUND: 1994 marked a decade since the inception of a prospective population based study on the value of neoadjuvant approach for soft tissue sarcomas of head, neck, and limbs at the Tom Baker Cancer Centre, Calgary, Alberta. To date, 42 patients have been followed for a minimum of 5 years or until death. METHODS: Each patient received a protocol of 60 mg to 90 mg of Adriamycin infused intra arterially or intravenously over 3 days into a vessel feeding the involved area, 30 Gy of radiotherapy given over 10 days, and complete resection of the sarcoma 4 to 6 weeks later. The lower dose was used empirically for smaller limbs (e.g., arm). RESULTS: Two of the 42 patients were immediate failures of protocol, with one requiring amputation and one requiring later reexcision. In the 38 appendicular lesions, the ultimate limb salvage rate was 97.5%. All tumors were associated with a high risk of local recurrence with 15 being previous local failures. The rest were deep and grade 2 or 3 lesions. Serious local complications were seen in one patient (2.5%) who had wound necrosis requiring reoperation. Minor wound complications were seen in five patients (12.5%) (one wound infection, one resolved edema, three long-term drainage). There was one local recurrence; thus 5-year local control was 97%. No patient had long-term morbidity related to the treatment. No effect on systemic control was suggested. CONCLUSION: Our report demonstrates that this combined modality approach provides superior local control of soft tissue sarcomas with low postoperative morbidity. PMID- 9367028 TI - Fluoroscopy-free placement of standard chest wall subcutaneous chronic venous access devices. AB - BACKGROUND: This study was undertaken to evaluate the potential benefits of using an electromagnetic detection system to guide the intraoperative placement of chronic venous access devices (CVADs). STUDY DESIGN: An electromagnetic detection system was used to guide catheter placement during 54 procedures. Surgery and radiation exposure times were recorded. An oncology nursing follow-up questionnaire assessed device function. A cost analysis was performed. Outcomes were compared to similar data from a fluoroscopic historical control group. RESULTS: Eight study patients required intraoperative fluoroscopy; in 46 procedures (85%) the electromagnetic detection system was the sole modality employed to guide CVAD placement. One line was subsequently found in the internal mammary vein (2% false negative rate). Mean surgery times for placement of CVADs were 79.5 and 84.5 minutes for the study and control groups (p = NS). Mean radiation exposure rates were 0.16 and 0.86 minutes per patient for the study and control groups (p < 0.01). There was no significant difference in device function between groups. Major complications in the study group were rare. Mean cost of CVAD placement was $1993 and $2517 for the study and control groups (p = 0.005), respectively. CONCLUSIONS: The use of the electromagnetic detection system resulted in accurate placement of chest wall CVADs in the majority of patients. This resulted in significant reductions in radiation exposure and cost of CVAD placement. PMID- 9367029 TI - The credentialing of American surgery. PMID- 9367030 TI - Extended resection for locally advanced colorectal carcinoma. PMID- 9367031 TI - How can we reduce the burden of osteoporosis? PMID- 9367032 TI - What is the impact of osteoporosis? AB - A body of evidence points towards a close connection between susceptibility to fractures and osteoporosis. The incidence of osteoporotic fractures, both in absolute figures and in age-specific figures, has increased worldwide throughout this century. Although some reports show that the age-specific incidence is levelling-off, there will be a continuously increasing number of individuals with such fractures that will have implications from an economical point of view not only for the affected individual but for society as a whole. The outcome after such fractures, especially those of the hip, is by no means always favourable, partly due to insufficient results after orthopaedic treatment and partly due to an already high comorbidity. Therefore, trying to prevent osteoporotic fractures by non-pharmacological or pharmacological regimens is of utmost importance. PMID- 9367033 TI - What determines peak bone mass and bone loss? AB - Bone mass at any point in life represents a balance between the amount of bone laid down during growth and development and the amount of bone lost with ageing. At a cellular level, these changes in bone mass occur as the result of bone remodelling; a process whereby bone resorbing cells (osteoclasts) and bone forming cells (osteoblasts) remove and replace small packets of bone at discrete points throughout the skeleton. This process is in turn regulated by a complex interaction between genetic factors and environmental influences such as nutrition and exercise, which affect bone cell function both directly and indirectly by altering the production of local and systemic hormones that modulate bone cell activity. In this chapter, I shall review the relative importance of genetic and environmental factors in regulating bone growth, peak bone mass, and bone loss. Discussion of the genetic aspects shall focus on recent data linking polymorphisms in candidate genes to bone mass and bone loss, and on the possible role which gene-environment interactions may have in regulating these processes. PMID- 9367034 TI - How can we measure bone quality? AB - Osteoporosis is a systematic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue. This leads to diminished biomechanical competence of the skeleton and is associated with low-trauma or atraumatic fractures. In the past decade, considerable progress has been made in the development of methods for assessing the skeleton non-invasively, so that osteoporosis can be better managed. While dual X-ray absorptiometry (DXA) is still the preferred methodology, several limitations will be addressed. Another densitometric technique which is widely accepted for diagnosis of spinal osteoporosis is single energy QCT. Measurements of vertebral trabecular bone mineral density (BMD) demonstrate larger percentage decrements between vertebrally-fractured subjects and normal controls, and confer higher relative risks for vertebral fracture than either anteroposterior or lateral DXA measurements. As an emerging alternative to photon absorptiometry techniques, there is a growing interest in the use of quantitative ultrasound (QUS) measurements for the non-invasive assessment of osteoporotic fracture risk in the management of osteoporosis. The attractiveness of QUS lies in the fact that indirect and in vitro experience has suggested that ultrasound may give information not only about BMD but also about architecture and elasticity. Whether or not combining QUS and DXA improve fracture prediction is still unclear and needs further analysis. Due to the growing evidence supporting the use of QUS in osteoporosis and the large number of QUS devices already on the market, a general clinical consensus on the application of QUS is urgently needed. Other techniques that are less widely used for the management of osteoporosis. For example, peripheral quantitative computed tomography, quantitative magnetic resonance (QMR) and magnetic resonance microscopy are promising tools for the evaluation of the skeleton. For example, the ability of QMR and high resolution magnetic resonance imaging has been explored and shows promise as a technique for assessing trabecular bone structure in osteoporosis. PMID- 9367036 TI - How do you know who needs prevention or treatment? AB - Osteoporosis is preventable with the various therapeutic options available today. It is therefore important to reach the patient who needs to be treated. If based only on clinical risk factors there is much room for therapeutic misassignation in both directions: too many and too few treatments. Generally speaking, only bone mass measurement can yield the correct risk for future fracture, and clinical factors taken alone might be misleading. Clinical factors can be used to modulate the therapeutic intervention based on assessment of bone mass. In very elderly people with several risk factors (poor vision, poor balance and awkward gait, use of psychotropic drugs, etc), bone mass measurements probably become less crucial in therapeutic decision, because factors other than bone mineral have also to be actively assessed. All in all, the use of cut offs of bone mineral density balanced with the clinical decision based on an individual examination, will allow assessment of the therapeutic level in a particular patient. A therapeutic intervention will never be an all or nothing phenomenon based on computerized data. PMID- 9367035 TI - Bone markers. AB - The recent development of specific and sensitive biochemical markers reflecting the overall rate of bone formation and bone resorption, has markedly improved the non-invasive assessment of bone turnover in various metabolic bone diseases, especially osteoporosis. The immunoassay of human osteocalcin recognizing the intact molecule and its major proteolytic fragment, along with that of bone alkaline phosphatase, are currently the most sensitive markers to assess bone formation. For bone resorption, the total urinary excretion of pyridinoline crosslinks measured by high pressure liquid chromatography has shown its superiority over all other markers for the clinical assessment of osteoporosis. The recent development of immunoassays recognizing either the free pyridinoline crosslinks or pyridinoline crosslinked-type I collagen peptides in urine and serum should allow a broad use of this sensitive resorption marker. Recent studies, some of them still in progress, define the clinical use of these markers: first, to improve the prognostic assessment of post-menopausal women in combination with bone mass measurement, i.e. their risk of developing osteoporosis and, ultimately, fractures and, second, to monitor the efficacy of anti-resorption drugs. PMID- 9367037 TI - Can we prevent fractures? AB - The primary aim of any intervention in osteoporosis is the prevention of fractures in individuals who have not yet fractured or the prevention of the progression of the disease in individuals with fragility fractures. There is currently insufficient evidence to recommend either a population-based prevention strategy or a strategy based on general screening with treatment of those individuals identified at high risk. Identification of subjects with strong clinical risk factors for osteoporotic fractures with subsequent measurement or not of bone mineral density as well as those with fragility fractures constitute at present the most rational approach to fracture prevention. Current measures to prevent osteoporotic fractures aim mainly at influencing bone mass and bone turnover and reducing the risk and impact of falls. Interventions that can reduce effectively the frequency of osteoporotic fractures in subjects at risk are available and new or alternative interventions are being developed. Issues related to the impact of these interventions on public health and health economics need to be addressed and methods to calculate the clinical outcomes in a way allowing comparison with outcomes of interventions in other common diseases should be developed. PMID- 9367038 TI - Hormone replacement therapy. AB - Oestrogen deficiency at the menopause leads to bone loss primarily as a result of increased bone turnover and an increase in the activity of osteoclasts. Hormone replacement therapy (HRT) reverses these changes, preventing menopausal bone loss and reducing fracture risk at the spine, hip, and wrist, although the magnitude of this reduction has not been accurately established. The optimal duration of therapy for the prevention of osteoporosis is uncertain but there is increasing evidence that life-long treatment after the menopause may be required to maintain maximum protection against fracture. The extraskeletal effects of long-term oestrogen therapy include protection against cardiovascular disease and a possible increase in the risk of breast cancer; the persistence of these effects after therapy is withdrawn is uncertain although there is some evidence that the increase in risk of breast cancer is seen only in current users. Furthermore, there is increasing evidence that the use of progestogens in combined formulations does not substantially alter either the cardiovascular benefits or the increased risk of breast cancer, although further studies are needed in this area. The emergence of 'no-bleed' preparations in recent years has increased the acceptability of HRT for some women, particularly those in older age groups. Finally, the development of tissue-selective oestrogen agonists is an exciting advance which may enable life-long therapy after the menopause to protect against cardiovascular and bone disease in the absence of significant side-effects. PMID- 9367039 TI - How do we manage specific types of osteoporosis? AB - Osteoporosis in children, adolescents and corticosteroid-treated patients represent a particular problem for clinicians. In children and adolescents, the main management question is whether any specific interventions can influence attainment of peak bone mass and so decrease the chance of osteoporosis in later adult life. The role of physical activity and calcium in particular are reviewed. In adolescence, osteoporosis is usually due to idiopathic juvenile osteoporosis or secondary to amenorrhoea or anorexia nervosa. These entities, as well as the management of corticosteroid-induced osteoporosis at all ages, are discussed. PMID- 9367040 TI - Osteoporosis in men. AB - Hip fractures in men account for one third of all hip fractures and have a higher mortality than in women. The public health burden will increase as the increase in the numbers of elderly men in the community increases. In addition, the age specific incidence of hip fractures may be increasing in some, but not all, countries. Vertebral fractures may be a public health problem as recent studies suggest that the prevalence in the community is 20-30%, similar to that reported in women. Forearm fractures should probably not be regarded as a public health problem. Peak bone mass is higher in men than women because men have bigger bones. Peak bone mineral density is the same. The amount of trabecular bone lost at the spine and iliac crest during ageing is similar in men and women. Cortical bone loss is less in men because endocortical resorption is less and periosteal formation is greater. Bone loss accelerates in elderly men because endocortical resorption and increasing cortical porosity increase the surface available for resorption. Bone fragility is less in men than women because: (a) the cross sectional surface of the bone is larger; (b) trabecular bone loss is less as a percentage of the higher peak bone mass; (c) trabecular bone loss occurs by thinning rather than perforation; and (d) periosteal appositional growth compensates for endocortical resorption by maintaining the bending strength of bone. Reduced BMD in men with fractures may be due to reduced peak bone size and mass, and bone loss. Bone loss occurs by reduced bone formation. Whether men with fractures have increased bone fragility due to reduced periosteal appositional growth during ageing is unknown. The age-related decline in testosterone, adrenal androgens, growth hormone, and insulin-like growth factor 1 may contribute to reduced bone formation and bone loss. Men with vertebral fractures often have hypogonadism or illnesses with few clinical features that should be considered with a high index of suspicion (alcoholism, myeloma, malabsorption, primary hyperparathyroidism, haemochromatosis, Cushing's disease). Secondary hyperparathyroidism may contribute to bone loss by activating bone turnover and so increasing the number of bone remodelling units with impaired bone formation in each. There is no proven treatment for osteoporosis in men because there have been no trials using anti-fracture efficacy as an end point. Testosterone replacement should be considered in men with proven hypogonadism and vitamin D deficiency should be corrected if present. Calcium supplements and bisphosphonates are reasonable options given the lack of information. PMID- 9367041 TI - How do we increase awareness of osteoporosis? AB - In the UK and throughout Europe 10 years ago, osteoporosis was not a word that existed in the vocabulary of the general public. The majority of doctors had dismissed osteoporosis as a normal process of ageing, affecting only the very elderly and about which nothing could be done. Why should it matter that awareness of osteoporosis was so low among the general public and the medical professions? For the newly launched National Osteoporosis Society in the UK, several questions needed to be answered: if osteoporosis was not an inevitable part of growing old, was it really a disease and how could action be implemented to treat it and prevent it? If fracture numbers and their costs were so much higher than had been thought, who should be informed of this? And if there were ways of treating and preventing osteoporosis, who should be made more aware, what should they be told, and how could such awareness-raising be done and paid for? Before real action could be undertaken, a considerable awareness programme would be needed to radically-alter traditional beliefs about bone health. PMID- 9367042 TI - Osteoporosis: outstanding issues. AB - Major advances have occurred in our knowledge of osteoporosis and its treatment in the past 10 years. This paper reviews aspects of the epidemiology, pathogenesis, and diagnosis of the disease that deserve further investigation. Although anti-resorption treatments such as hormone replacement therapy and bisphosphonates have been shown to reduce the incidence of osteoporotic fractures, there is room for improving available treatments. Today, there is no bone-forming agent that has been shown to decrease fracture rate, and several agents are under clinical investigation. The potential value of combined therapy will also be discussed. PMID- 9367043 TI - Purchasing strategies: institutions look for new models to increase efficiency and decrease costs. PMID- 9367044 TI - Regulatory harmonization and standards development--opportunities for cooperation? PMID- 9367045 TI - An evaluation of mobile computing for information access at the point of care. PMID- 9367046 TI - Business management and the environment of care standards. AB - In summary, the entire JCAHO manual is built around the concept of "know thyself." This expectation creates the need to engage in a substantial rework of existing practices to remove communication barriers and to eliminate turf warfare. The focus of the standards is on the patient. All aspects of the patient care delivery cycle are examined during survey, as are key elements of the business-management activities. The EC standards are a case study of business management. They expect leadership and planning, development of human resources, management of information, and improvement of performance. They expect that all four of these management tools will be exercised by all managers and staff members who have an impact on or are impacted by the seven elements of the EC function. The primary focus is on teamwork among providers and maximizing benefits to patients. PMID- 9367047 TI - Controller for an axial-flow blood pump. AB - An axial-flow ventricular assist device (VAD) under development at the authors' facility is intended for use as a long-term implantable device. At high speeds axial-flow VADs can collapse the native ventricle and damage the heart muscle, lung tissue, and blood. A prototype algorithm was developed to maintain physiologic perfusion to the vital organs while preventing ventricular collapse, through analysis of the electrical current waveform of the motor. The premise of the control algorithm is that the hemodynamics of the patient are reflected in the shape of this waveform. This approach is intended to eliminate the need for invasive sensors, thus effectively using the pump itself as a transducer. The control algorithm regulates the speed of the pump by comparing the motor-current waveform with reference waveforms using a matched filter. The matched filter was evaluated by its classification and differentiation performance. Thus far, the authors have been able to classify the waveforms into one of the four physiologic regions (below, within, or above the optimal range, and ventricular suction) with over 90% reliability. Ongoing work is directed toward improving the detection of ventricular suction, as this condition must be strictly avoided. PMID- 9367048 TI - Toward engineering for blood pressure surveillance. PMID- 9367049 TI - Response--the tolerance-hyperbaric test for hypertension diagnosis. PMID- 9367050 TI - Final rebuttal: response--more on software chronobioengineering for blood pressure surveillance. PMID- 9367051 TI - Bioprosthetic heart valves. PMID- 9367052 TI - The reengineering of clinical engineering. PMID- 9367053 TI - Cell mediated immunity in virus infections. AB - The discovery of the molecular nature of T cell-mediated immunity is reviewed in a historical context. Current approaches to understanding virus-induced inflammatory processes are described. PMID- 9367054 TI - Transient energy coupling between rhizobia and legume cells mediated by the peribacteroid membrane ATPase proton pump. AB - We present a model for the metabolic coupling between rhizobia and plant cell in the nitrogen-fixing legume root nodules. The symbiosome, an organelle-like structure formed by the modified rhizobia (the bacteroids) enclosed by a plant cell derived peribacteroid membrane, is an unique structure in which two energized membranes are closely packed: the inner bacteroid membrane and the peribacteroid membrane that possesses an ATPase proton pump. The model is based on the following points: (i) The permeability for hydrogen ions of the outer membrane of the rhizobia. (ii) The reversibility of the ATPase proton pump of the peribacteroid membrane [Szafran, M.M. and Haaker, H. (1995) Plant Physiol. 108, 1227-1232]. (iii) The relative affinites for oxygen of the bacteroid and plant mitochondria terminal oxidases, and the prevailing oxygen concentration inside the nodule, which results in aerobic metabolism for the bacteroid, but in quite fermentative catabolism for the host plant cell. We propose that the bacteroid can transiently supply free energy to the plant cell in the form of protonmotive force by the movement of hydrogen ions from the bacteroid periplasmic space to the plant cytoplasm through the peribacteroid membrane ATPase. The proposed hydrogen ion flux could be dependent on the phosphorylation potential in both the plant cell cytoplasm and the bacteroid, and the simultaneous ion movements to avoid the development of opposite delta psi. It could be important in situations of transient ATP depletion inside plant cell, which involves the block of ammonia assimilation and, subsequently, the inhibition of bacteroid nitrogenase. PMID- 9367056 TI - Lysyl oxidase, cellular senescence and tumor suppression. AB - Replicative senescence may provide a mechanism of tumor suppression and tumor suppressor genes of the extracellular matrix, like lysyl oxidase, may play a role in cellular senescence. To test this hypothesis and determine whether the extracellular matrix may serve as a marker, the steady-state levels of human lysyl oxidase, alpha-I type III collagen and beta-actin transcripts were assessed in various cell lines during in vitro passage. Northern hybridization analysis showed a significant increase in the levels of progeria fibroblast extracellular matrix mRNAs immediately preceding senescence. The levels of these mRNAs were unaffected in age-matched normal fibroblast and fetal fibroblast cell lines. PMID- 9367055 TI - Effect of N-acyl-phosphatidylethanolamine on the membrane fusion between Sendai virus and liposome. AB - We have compared the properties of two N-acyl derivatives of dilauryl phosphatidylethanolamine on lipid polymorphism, vesicle leakage and Sendai virus fusion. The derivatives contained either an N-lauroyl group (NLPE) or an N-acetyl group (NAcPE). Only the NAcPE markedly affected the bilayer to hexagonal transition temperature of dielaidoyl phosphatidylethanolamine, shifting it to higher values. In contrast the NLPE slightly lowered this phase transition temperature. The two lipids also have opposite effects on leakage from small unilamellar vesicles of egg phosphatidylcholine. The NLPE inhibits leakage, while the NAcPE promotes it. This vesicle stabilizing effect of NLPE against leakage is not manifested in alterations of rates or extents of Sendai virus fusion to liposomes of egg phosphatidylethanolamine plus 2% ganglioside GD1a. The NLPE has no effect, while the NAcPE reduces the observed fusion, at least in part as a consequence of a reduction in the final extent of fusion. These results demonstrate that the bilayer stabilizing effects of NLPE do not result in a lower rate of viral fusion. Furthermore, these bilayer stabilizing effects against leakage are not solely a function of the lipid headgroup but also require a structure with three long acyl chains. The reduced leakage is not related to a loss in monolayer curvature strain. PMID- 9367057 TI - Folate receptors in malignant and benign tissues of human female genital tract. AB - We have characterized the folate receptor in malignant and benign tissues of human female genital tract (Fallopian tube and benign and malignant tissues of uterus). Radioligand binding displayed characteristics similar to those of other folate binding proteins. Those include a high-affinity type of binding (K = 10(10)M-1), apparent positive cooperativity, a slow dissociation at pH 7.4 becoming rapid at pH 3.5, and inhibition of binding by folate analogues. The gel filtration profile of Triton X-100 solubilized tissue contained two large peaks of 3H-folate labelled protein (> = 130 and 100 kDa) as well as a 25 kDa peak. Only a single band of 70 kDa was seen on SDS-PAGE immunoblotting. The large molecular size forms on gel filtration appear to represent folate receptors having a hydrophobic membrane anchor inserted into Triton X-100 micelles. The folate receptor of female genital tract showed cross-reactivity in ELISA and positive immunostaining with rabbit antibodies against human milk folate binding protein. Variations in the ratio of immunoresponse to total high affinity folic acid binding suggests the presence of multiple isoforms of the receptor in different types of malignant and benign tissues. PMID- 9367058 TI - Risk factors for malignant diseases: a cohort study on a population of 22,946 Icelanders. AB - The records of a cohort of 11,580 females and 11,366 males participating in an Icelandic cardiovascular risk factor study were linked with the Icelandic Cancer Registry, identifying 1,785 males and 1,490 females who had been registered with neoplastic diseases from 1968 to 1995. The interval between the time of measurement of the variables and the diagnosis of the malignancy ranged from 4 to 27 years. The variables consisted of answers from a questionnaire on smoking and the use of hypertensive drugs and anthropometric and biochemical measurements. Cox's regression was applied to analyze the predictive power of the variables on the risk of cancer after the first examination at the Heart Preventive Clinic, Reykjavik. Univariate analyses, adjusted for age, were performed for each variable and each major site. Within each major site, multivariate regression analysis was applied for variables that were found significantly (10% level in univariate analysis) positive or negative as risk factors. The results show that smoking is the most important risk factor, negative only for endometrium. For lung cancer, the risk is twice as strong for females as it is for males, whereas for pancreas, males have a relative risk ratio of 4.5, compared with 2.4 for females. Height is a risk factor for all sites for each sex, for breast in females, and for kidney in males. Several anthropometric risk factors were studied. Some of these can describe positive or negative relative risk ratios for cancer, and their use may shed light on cancer pathogenesis. Serum cholesterol is a negative risk factor for breast cancer in females, but triglycerides are a positive risk factor for cervix cancer in females and for colon or rectum and thyroid cancer in males. Serum glucose is a positive risk factor for prostate cancer and a negative risk factor for lymphomas and leukemias. PMID- 9367059 TI - Low-risk diet for breast cancer in Italy. AB - To define a low-risk diet for breast cancer in Italy, a multicentric case-control study of 2569 incident cases of breast cancer and 2588 controls from Italy was analyzed. A logistic regression model was applied to the estimated intake of five macronutrients and used to compute a diet-related risk score (RS). The pattern of macronutrient and food group intake across RS deciles was defined. The mean of diet-related RSs across subsequent risk deciles ranged from 0.83 to 1.44. Total energy intake first decreased slightly, from the first to the second decile, and then increased, mostly in the last three risk deciles. Intake of starch increased in absolute and relative terms, whereas saturated fat intake rose in absolute terms but remained stable as a proportion. A relative decline was observed for unsaturated fat and sugars, with a hint, however, of U-shape effect. From a food group viewpoint, there was a marked increase in the intake of bread and cereal dishes, cakes and desserts, and refined sugar across subsequent deciles, whereas the consumption of vegetables, olive and seed oils, and fruit decreased. PMID- 9367060 TI - Breast cancer survival and the timing of tumor removal during the menstrual cycle. AB - In a retrospective cohort study of 262 premenopausal breast cancer patients treated at the Mayo Clinic between 1965 and 1985, we investigated whether survival was associated with the timing of tumor removal during the menstrual cycle. Participants were women < or = 50 years old who had not used exogenous hormones, been pregnant, been lactating, or given birth within 6 months of diagnosis. The menstrual cycle day at surgery was used to assign women to group 1 (cycle days 0-7), group 2 (cycle days 8-15), or group 3 (after cycle day 15). Cox proportional hazards analysis adjusting for age at diagnosis, stage, tumor size, grade, and node involvement showed a nonsignificantly worse survival for group 2 than for group 3 [hazard ratio (HR), 1.41; 95% confidence interval (CI), 0.89 2.23]. Stratification revealed that the association between survival and timing of tumor removal during the menstrual cycle was slightly stronger among patients with stage II disease (adjusted HR, 1.56; 95% CI, 0.92-2.63). The association was the same among patients with stage II disease and node involvement (adjusted HR, 1.57; 95% CI, 0.82-3.03). Prospective studies using hormone measurements to define menstrual cycle status more accurately than the reported day of the menstrual cycle could provide further insight about the postulated association. PMID- 9367061 TI - Intake of carrots, spinach, and supplements containing vitamin A in relation to risk of breast cancer. AB - Intake of fruits, vegetables, vitamin A, and related compounds are associated with a decreased risk of breast cancer in some studies, but additional data are needed. To estimate intake of beta-carotene and vitamin A, the authors included nine questions on food and supplement use in a population-based case-control study of breast cancer risk conducted in Maine, Massachusetts, New Hampshire, and Wisconsin in 1988-1991. Multivariate-adjusted models were fit to data for 3543 cases and 9406 controls. Eating carrots or spinach more than twice weekly, compared with no intake, was associated with an odds ratio of 0.56 (95% confidence interval 0.34-0.91). Estimated intake of preformed vitamin A from all evaluated foods and supplements showed no trend or monotonic decrease in risk across categories of intake. These data do not allow us to distinguish among several potential explanations for the protective association observed between intake of carrots and spinach and risk of breast cancer. The findings are, however, consistent with a diet rich in these foods having a modest protective effect. PMID- 9367062 TI - A case-cohort study of an early biomarker of lung cancer in a screening cohort of Yunnan tin miners in China. AB - We initiated the present study to evaluate the accuracy of a new epithelial biomarker of early lung cancer. We tested the hypothesis that expression of a tumor-associated antigen by exfoliated sputum epithelial cells has greater accuracy (sensitivity and specificity) for the detection of preclinical, localized lung cancer than do routine clinical detection methods. Monoclonal antibody (MAb) 703D4 recognizes heterogeneous nuclear ribonuclear protein (hnRNP) A2/B1. We compared the accuracy of hnRNP up-regulation with cytology and radiographic screening for lung cancer detection in miners who were highly exposed to tobacco smoke, radon, and arsenic in southwestern China. The results showed that MAb 703D4 detection of hnRNP expression by sputum epithelial cells had greater accuracy for the detection of lung cancer than did routine screening methods, particularly for early (localized) disease. Among 57 cases and 76 noncases at the first screening, overall MAb detection of hnRNP was more sensitive (74 versus 21% for cytology and 42% for chest x-ray) but had lower specificity (70 versus 100% for cytology and 90% for chest x-ray) than standard methods. Recognizing hnRNP up-regulation resulted in detection of approximately one-third more early cases than did the combination of X-ray and cytology. Detection of hnRNP A2/B1 expression appears to be a good initial screening test for lung carcinogenesis, as it identified 74% of those who developed subsequent clinical lung cancer. Future studies might separate individuals with high lung cancer risk by MAb detection, confirming the positives with markers having greater specificity (e.g., clinical studies that become positive later in the morphological progression). PMID- 9367063 TI - Genetic polymorphisms of CYP2E1, GSTM1, and GSTT1; environmental factors and risk of oral cancer. AB - Both genetic and environmental factors are involved in the development of cancer; some phase I and II enzymes involved in the metabolism of carcinogens are polymorphic in genotypes. This case-control study focused on the interactions between oral cancer risk factors and genetic polymorphisms of cytochrome P-450 (CYP) 2E1 and glutathione S-transferase (GST) M1 and GSTT1. A total of 41 male oral cancer cases was recruited from National Taiwan University Hospital, and 123 healthy controls frequency-matched on ethnicity, sex, and age were recruited from residents living in Taipei City and Taipei County. History of cigarette smoking, alcohol drinking, and betel quid chewing was obtained through a standardized questionnaire interview, and genotypes of CYP2E1, GSTM1, and GSTT1 were determined by PCR. Cigarette smoking, alcohol drinking, and betel quid chewing were significantly associated with the risk of oral cancer in a dose-response relationship. All betel quid chewers smoked cigarettes in both the case and control groups. In the multiple logistic regression analysis, those who had null genotypes of GSTM1 and/or GSTT1 had an increased oral cancer risk compared with those who had non-null genotypes of both GSTM1 and GSTT1, showing a multivariate adjusted odds ratio (OR) of 4.6 with a 95% confidence interval (CI) of 0.9-23.7 (P = 0.08). The CYP2E1 c1/c2 and c2/c2 genotypes were associated with a significantly increased oral cancer risk compared with the c1/c1 genotype among those who did not chew betel quid (OR, 4.7; 95% CI, 1.1-20.2), but not among betel quid chewers. Habitual alcohol drinking was associated with a significantly increased oral cancer risk, showing an OR of 3.0 (95% CI, 1.1-8.8). These results implied that there are gene-gene and gene-environment interactions in the development of oral cancer. PMID- 9367064 TI - The risk of developing lung cancer associated with antioxidants in the blood: ascorbic acid, carotenoids, alpha-tocopherol, selenium, and total peroxyl radical absorbing capacity. AB - Lung cancer cases diagnosed during the period 1975 through 1993 and matched controls were identified in the rosters of Washington County, Maryland residents who had donated blood for a serum bank in 1974 or 1989. Plasma from participants in the 1989 project was assayed for ascorbic acid; serum or plasma was assayed for participants in either project for alpha- and beta-carotene, cryptoxanthin, lutein/zeaxanthin, lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity. Among the total group of 258 cases and 515 controls, serum/plasma concentrations were significantly lower among cases than controls for cryptoxanthin, beta-carotene, and lutein/zeaxanthin with case-control differences of -25.5, -17.1, and -10.1%, respectively. Modest nonsignificant case control differences in a protective direction were noted for alpha-carotene and ascorbic acid. There were only trivial differences for lycopene, alpha tocopherol, selenium, and peroxyl radical absorption capacity. Findings are reported for males and females and for persons who had never smoked cigarettes, former smokers, and current smokers at baseline. These results and those from previous studies suggest that beta-carotene is a marker for some protective factor(s) against lung cancer; that cryptoxanthin, alpha-carotene, and ascorbic acid need to be investigated further as potentially protective factors or associates of a protective factor; and that lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity are unlikely to be associated with lung cancer risk. Until specific preventive factors are identified, the best protection against lung cancer is still the avoidance of airborne carcinogens, especially tobacco smoke; second best is the consumption of a diet rich in fruits and vegetables. PMID- 9367065 TI - Antioxidant nutrients: associations with persistent human papillomavirus infection. AB - Research from the past several years has definitively shown intermediate and high risk-type human papillomavirus (HPV) infection to play a significant role in cervical carcinogenesis. Persistent compared with intermittent infection appears to confer an elevated risk, and cofactors may be necessary to allow the virus to progress to cervical cancer. We explored the association between circulating concentrations of the antioxidant nutrients (alpha- and beta-carotene, lutein, lycopene, beta-cryptoxanthin, alpha-tocopherol, gamma-tocopherol, and ascorbate) and persistent HPV infection among 123 low-income Hispanic women who were all nonsmokers and were not currently using vitamin and mineral supplements. In addition, the association between these nutrients and grade of cervical pathology, independent of HPV status, was assessed. Intermediate and high risk type HPV infection was assessed by the Digene Hybrid Capture System at two time points, 3 months apart. At the second interview, cytology, colposcopy, and a fasting blood draw were conducted. Mean concentrations of serum and plasma antioxidant nutrients were calculated within categories of HPV status (two times HPV negative, one time HPV positive, and two times HPV positive) and colposcopy. Adjusted mean concentrations of serum beta-carotene, beta-cryptoxanthin, lutein, and alpha- and gamma-tocopherol were on average 24% (P < 0.05) lower among women two times HPV positive compared with either two times HPV negative or one time HPV positive. Independent of HPV status, alpha-tocopherol was significantly inversely associated with grade of cervical dysplasia (normal, 21.57 microM; cervical intraepithelial neoplasia III, 17.27 microM). The results obtained in this study need to be confirmed in larger cohort studies with a longer follow-up period. PMID- 9367066 TI - p53 mutations detected in colorectal carcinoma patients in Hong Kong. AB - A mutational spectrum for exons 5-8 of the p53 tumor suppressor gene in colorectal carcinomas in Hong Kong Chinese was established. Ninety-nine colorectal carcinomas from Hong Kong patients were analyzed for mutations in p53 gene by PCR-single-strand conformation polymorphism analysis and direct DNA sequencing. Thirty-five of the 99 tumors (35.4%) contained mutations. Point mutations accounted for 80% of all genetic changes and were predominantly base transitions at CpG dinucleotide sites, mutations that were also predominant in Caucasian carcinomas. The major hot spots at codons 175 and 248 of p53 in Caucasians are also hot spots in the Chinese gene. Identical mutations in codons 152 and 306 were detected in two independent tumors in the Chinese, which were reported only rarely in Caucasians. Moreover, a significantly higher frequency (20%) of deletion and insertion mutations was observed in Hong Kong colorectal cancer patients. Distinct genetic and/or environmental factors may contribute to these findings. PMID- 9367067 TI - Methodological findings and considerations in measuring colorectal epithelial cell proliferation in humans. AB - The methodological issues for measuring colorectal epithelial cell proliferation, an intermediate end point for studies of colon neoplasia, in epidemiological studies are deceptively numerous and complex, with few methodological data available. Accordingly, during our experience with measuring colorectal epithelial cell proliferation from nearly 500 participants attending over 1300 study visits over a 6-year period, we recorded data on a variety of measurement variations. Methods investigated included rectal biopsy technique, general histological and labeling procedures [including the tritiated thymidine, 5 bromodeoxyuridine (BrdUrd), and the proliferating cell nuclear antigen (PCNA) immunohistochemical techniques used to label S-phase cells in colonic crypts in rectal biopsy specimens], biopsy scoring procedures, and summary scoring methods. Findings include that the PCNA technique was the simplest, most economical, and least time-consuming. The BrdUrd labeling failure rate was 15% versus < 1% for PCNA. The percentage of labeled cells (labeling index) was highest using PCNA in biopsies processed without prior incubation, intermediate using PCNA in biopsies processed with prior incubation as for BrdUrd, and lowest using BrdUrd. The percentage of labeled cells that were in the upper 40% of the crypt (phi h) was higher using BrdUrd than PCNA; visit-to-visit correlations were higher using PCNA (r = 0.51 versus 0.35), and visit-to-visit variability was lower and between person variability was higher using PCNA. Intra- and inter-rater reliabilities for the techniques were comparable (PCNA intra-rater r = 0.93, inter-rater r = 0.92). The PCNA technique, compared to the BrdUrd technique, is more feasible and reliable, provides a more accurate estimate of the labeling index, and cell proliferation measures determined with PCNA have statistical properties that are generally more favorable for detecting differences in clinical trials. Thus, the PCNA technique may be preferable to techniques requiring incubation of biopsies. Other methodological findings lead us to recommend that, for larger studies measuring colorectal epithelial cell proliferation on outpatient rectal biopsies, biopsies should be taken 10 cm above the anus using a flexible, preferably jumbo cup, endoscopic forceps through a rigid sigmoidoscope, and histological sections should be 3 microns thick taken 50 microns apart. PMID- 9367068 TI - Age-related negative associations between parameters of cytogenetic damage and ex vivo (+/-)-anti-benzo(a)pyrene diolepoxide-induced unscheduled DNA synthesis in smoking humans. AB - Chemical or physical modification of DNA may cause an increase in genomic mutations or other genetic alterations, which may ultimately result in the onset of cancer. To avoid these deleterious effects of DNA damage, humans possess DNA repair mechanisms. Decreased DNA repair, induced ex vivo by UV light or ionizing radiation in human peripheral blood lymphocytes (PBLs), has been associated with aging. The aim of this study was to investigate whether repair of DNA damage, after ex vivo exposure of PBLs obtained from smokers (n = 20) to (+/-)-anti benzo(a)pyrene diolepoxide [(+/-)-anti-BPDE], which is a mixture of reactive metabolites from the environmental carcinogen benzo(a)pyrene, is also associated with age. Furthermore, age-related associations between ex vivo (+/-)-anti-BPDE induced DNA repair and the frequency of endogenous cytogenetic damage (sister chromatid exchange frequencies and micronuclei frequencies) in PBLs were evaluated. A statistically significant negative association was observed between ex vivo (+/-)-anti-BPDE-induced unscheduled DNA synthesis and age of the donors. Also, parameters of endogenous lymphocytic cytogenetic damage were negatively associated with ex vivo (+/-)-anti-BPDE-induced unscheduled DNA synthesis and positively associated with age in this population. It is concluded that, with increasing age, a decrease in lymphocytic excision repair capacity may be responsible for increased lymphocytic DNA damage in smokers. PMID- 9367069 TI - Effect of retinol in preventing squamous cell skin cancer in moderate-risk subjects: a randomized, double-blind, controlled trial. Southwest Skin Cancer Prevention Study Group. AB - We conducted a randomized, double-blind, controlled trial to examine the efficacy of retinol supplementation on the incidence of first new nonmelanoma skin cancer in moderate-risk subjects. A total of 2297 free-living subjects were enrolled; subjects resided in Arizona (median age, 63 years) and had a history of more than 10 actinic keratoses and at most 2 squamous cell carcinoma (SCC) or basal cell carcinoma (BCC) skin cancers. Subjects were randomly assigned to receive oral retinol (25,000 IU) or placebo supplementation daily for up to 5 years. The primary end points for the trial were time to first new SCC or BCC. During a median follow-up time of 3.8 years, we found that 526 subjects had a first new skin cancer. Comparing retinol-supplemented subjects with placebo-supplemented subjects showed a hazard ratio for first new SCC of 0.74 (95% confidence interval, 0.56-0.99; P = 0.04). The hazard ratio of first new BCC for the retinol supplemented subjects compared with those receiving placebo was 1.06 (95% confidence interval, 0.86-1.32; P = 0.36). Potentially adverse symptoms that were judged to be associated with retinol were rare (approximately 1% higher in the retinol group than in the control group). Therefore, we concluded that daily supplementation with 25,000 IU of retinol was effective in preventing SCC, although it did not prevent BCC. PMID- 9367071 TI - p53 mutations in esophageal tumors from a high incidence area of China in relation to patient diet and smoking history. AB - Esophageal tumors from 29 patients residing in Guangzhou, China were examined for mutations in exons 5-8 of the p53 tumor suppressor gene and for p53 protein accumulation in tumor cell nuclei. Anamnestic data for each patient, which included information on family history of cancer, tobacco smoking, drinking of alcoholic beverages, and dietary habits such as consumption of pickled vegetables, were recorded. Screening of DNA from tumor cells microdissected from biopsies was performed by PCR amplification of p53 gene exons 5-8, denaturing gradient gel electrophoresis analysis, and DNA sequencing. Mutations were identified in 20 of 29 tumors (69%). All tumors harboring a missense mutation in the p53 gene also showed nuclear accumulation of the tumor suppressor protein by immunohistochemistry. The most common p53 mutations in these tumors were guanine to adenine (G-->A) transitions (10 of 20 tumors; 50%). We did not find multiple mutations at codon 176, in contrast to Lung et al. in their recent study of esophageal cancer patients from Guangzhou (M. L. Lung et al., Cancer Epidemiol. Biomark. Prev., 5: 277-284, 1996). The mutation prevalence was high both in smokers (13 mutations in 20 smokers; 65%) and in nonsmokers (7 of 9 tumors with mutations; 78%), an observation that differs from that of studies in European and North American patients, which demonstrate a much higher prevalence of p53 mutations in smokers than in nonsmokers (reviewed in R. Montesano et al., Int. J. Cancer Predict. Oncol., 69: 225-235, 1996.). Our findings in this pilot study of tumor suppressor gene mutations in patients from Guangzhou support a large body of epidemiological observations pointing to dietary mutagenic carcinogens peculiar to populations in China at high risk of esophageal cancer. PMID- 9367070 TI - Trial of retinol and isotretinoin in skin cancer prevention: a randomized, double blind, controlled trial. Southwest Skin Cancer Prevention Study Group. AB - The objective of this study was to examine the effect of retinol and isotretinoin on the incidence of nonmelanoma skin cancer in high-risk subjects. A total of 525 participants with a history of at least four basal cell carcinomas (BCCs) and/or cutaneous squamous cell carcinomas (SCCs) were entered into a randomized, double blind, placebo-controlled trial, performed in free-standing study clinics. Participants were randomly assigned to receive oral retinol (25,000 units), isotretinoin (5-10 mg), or placebo supplementation daily for 3 years. The time to first new occurrence of BCC or cutaneous SCC was used as the outcome measure. During the study period, 319 BCCs and 125 cutaneous SCCs were diagnosed clinically and pathologically. There were no differences between those who received retinol, isotretinoin, or the placebo, with regard to the time to first occurrence or to the total number of tumors noted. No beneficial effects were noted with regard to the prevention of nonmelanoma skin cancer with either retinol or isotretinoin. PMID- 9367072 TI - Androgens in serum and the risk of prostate cancer: a nested case-control study from the Janus serum bank in Norway. AB - We tested the hypothesis that serum levels of testosterone (T), dihydrotestosterone (DHT), and the DHT metabolite 3 alpha,17 beta-androstanediol glucuronide are positively associated with the risk of prostate cancer. This nested case-control study was based on the cohort of men who donated blood to the Janus serum bank at Oslo University Hospital (Oslo, Norway) between 1973 and 1994. Cancer incidence was ascertained through linkage with the Norwegian Cancer Registry. The study included sera from 59 men who developed prostate cancer (cases) subsequent to blood donation and 180 men who were free of any diagnosed cancer (controls) in 1994 and were of similar age (+/- 1 year) and had similar blood storage time (+/- 6 months) to the cases. Neither T, DHT, nor the ratio T:DHT was associated with risk of developing prostate cancer. Compared to the bottom quartile, the odds ratio (OR) associated with the top quartile of T was 0.83 [95% confidence interval (CI), 0.36-1.93]; the OR for the top (compared to the bottom) quartile of DHT was 0.83 (95% CI, 0.36-1.94), and the equivalent OR for T:DHT was 1.31 (95% CI, 0.58-2.97). Similarly, 3 alpha,17 beta-androstanediol glucuronide showed no association with prostate cancer risk; the OR for the top (compared to the bottom) quartile was 1.10 (95% CI, 0.41-2.90). These results showed no association, positive or negative, between androgens measured in serum and the subsequent risk of developing prostate cancer. PMID- 9367073 TI - Human studies of calcium supplementation and colorectal epithelial cell proliferation. AB - The kinetics of colorectal epithelial cell proliferation (CECP) have been found to be altered in patients at increased risk for colon cancer. Altered CECP kinetics include an increase within the colon crypts of the overall proportion of proliferating cells (labeling index; LI) and the proportion of proliferating cells that are in the upper 40% of the crypts (phi h). Use of CECP as a biomarker to measure effects of calcium interventions on the colon has been reported in five small uncontrolled clinical trials, nine small randomized placebo-controlled trials, and three full-scale randomized placebo-controlled trials. All five uncontrolled trials indicated substantial and significant decreases in proliferation. Of the nine small controlled trials, three found statistically significant decreases in the LI, and the remainder were inconclusive because of insufficient sample size. Of the three full-scale trials, one found a decrease in, or normalization of, the phi h but no effect on the LI; a second found an increase in the phi h but no effect on the LI; and the third, which did not measure the phi h, also found no effect on the LI. Differences between the two full-scale trials that measured the phi h were that the negative trial was multicentered, used multiple types of bowel-cleansing preparations, had no baseline measurements of CECP, and had low intrareader reliability for CECP scoring. The positive trial was single centered, used no bowel-cleansing preparations, measured CECP prior to, and at three precise intervals after, randomization, and had high intrareader reliability for CECP scoring. The current literature indicates that in humans, it is unlikely that calcium supplementation can substantially lower CECP rates, but it may normalize the distribution of proliferating cells within colon crypts. PMID- 9367074 TI - Correspondence Re: C. Bolognesi et al., Age-related increase of baseline frequencies of sister chromatid exchanges, chromosome aberrations, and micronuclei in human lymphocytes. Cancer Epidemiol. Biomark. Prev., 6: 249-256, 1997. PMID- 9367075 TI - Prospective randomized trials in melanoma: defining contemporary surgical roles. PMID- 9367076 TI - Advances in rectal cancer treatment. PMID- 9367077 TI - Molecular and surgical advances in pediatric tumors. PMID- 9367078 TI - Advances in reconstruction for cancer patients. PMID- 9367079 TI - New developments in soft tissue sarcoma. PMID- 9367080 TI - Advances in the diagnosis and treatment of adenocarcinoma of the pancreas. PMID- 9367081 TI - Recent advances in bone sarcomas. PMID- 9367082 TI - Thyroid carcinoma. AB - During the past years advances have been made in the understanding of the molecular mechanisms involved in the initiation and progression of thyroid carcinoma. Mutations in tumor suppressor genes such as p53 and oncogenes such as N-ras may be important for progression of well-differentiated thyroid carcinomas. Activation of the ret protooncogene located on chromosomal region 10q11.2 has been identified as a key factor in the initiation of papillary and medullary carcinoma. Integration of these discoveries into a prognostic classification scheme may allow us to better predict the biologic behavior of tumors in individual patients. Despite the recent advances in our understanding of the molecular events occurring during thyroid carcinogenesis, major questions persist regarding aspects of patient management. New diagnostic modalities may enable us to noninvasively discriminate between benign and malignant thyroid nodules, and to detect recurrent disease earlier. Although the optimal surgical procedure for well-encapsulated tumors is still debated, recent clinical studies have shown that for those patients with tumors > 1.5 cm, the routine use of RAI and hormone suppression can improve local control and survival rates. Findings in two recent reviews suggest that patients with widely invasive thyroid masses benefit from the surgical removal of all gross tumor. Further investigation is required to define the role of adjuvant radiotherapy and the most appropriate management of unresectable disease. Incorporation of prognostic markers into clinical staging systems should allow surgeons to better tailor their treatment plans for each patient. Translation of recent basic science advances into the clinical arena may also aid in the development of novel treatment strategies for patients with aggressive tumors. PMID- 9367083 TI - Changing trends in the diagnosis and treatment of early breast cancer. PMID- 9367084 TI - Classification, staging, and management of non-Hodgkin's lymphomas. PMID- 9367085 TI - Multiple endocrine neoplasia. PMID- 9367086 TI - Advances in the diagnosis and treatment of gastrointestinal neuroendocrine tumors. PMID- 9367087 TI - Contemporary approaches to gastric carcinoma. PMID- 9367088 TI - New strategies in locally advanced breast cancer. PMID- 9367089 TI - Biliary tract cancer. PMID- 9367090 TI - Minimally invasive surgery in surgical oncology. PMID- 9367091 TI - Prognostic factors in surgical resection for hepatocellular carcinoma. PMID- 9367092 TI - Colon cancer. PMID- 9367093 TI - Early versus late coronary stenting following acute myocardial infarction: results of the STENTIM I Study (French Registry of Stenting in Acute Myocardial Infarction). AB - This study was undertaken to determine the feasibility and safety of coronary stenting in acute myocardial infarction (AMI). In AMI, primary percutaneous transluminal coronary angioplasty (PTCA) is accepted as the preferred method of reperfusion for patients presenting at highly experienced centres. Until recently, however, stenting has been avoided during AMI because of a potential high risk of thrombosis. This prospective observational study carried out in 20 centres and included 648 consecutive patients who underwent PTCA with stent implantation for AMI. Of these 648 patients, 269 (41.5%, Group 1) were dilated early (< 24 hr) after the onset of the symptoms (75% treated by direct PTCA) and 379 (58.5%, Group 2) were dilated between 24 hr and 14 days after AMI. Combined therapy with ticlopidin and aspirin was used after the procedure. Bailout stenting occurred more often in Group 1 than in Group 2 (17% vs. 9.5%)(P < 0.05). Angiographic successful stenting was similar in both groups of patients (96% vs. 97%). During the hospital follow-up period, stent thrombosis occurred in eight patients (3%) in Group 1 and in six patients (1.6%) in Group 2 (NS). There was 14 deaths (5.2%) in Group 1 and 11 deaths (3.9%) in Group 2 (NS). After multivariate analysis bailout stenting was identified as the sole predictor of stent thrombosis (P < 0.0001). Vascular access-site complications occurred in six patients (1%) with no difference between the two groups. This study indicates that patients who receive a coronary stent in AMI can be managed safely with antiplatelet therapy. Randomized studies are needed to determine the precise indication for coronary stenting as an adjunct to primary PTCA. PMID- 9367094 TI - Pharmacologic prevention of acute ischemic complications of coronary angioplasty. AB - The risk of acute coronary occlusion following percutaneous transluminal coronary angioplasty (PTCA) has remained high despite the traditional use of heparin and aspirin. Interest has focused on newer strategies for preventing intracoronary thrombus formation, which is an important mechanism of abrupt vessel closure. Pretreatment with thrombolytic agents has failed vigorous testing in double-blind trials. Retrospective and observational studies have indicated that pretreatment with intravenous heparin is of benefit in patients with unstable symptoms, but prolonged infusion after angioplasty increases bleeding complications without improving outcomes. Subcutaneous heparin may be safer, but has not proved more effective. Oral dipyridamole has shown no advantage over aspirin, although there is evidence to suggest a benefit when given intravenously. Direct thrombin inhibitors (such as hirudin and hirulog) are associated with fewer early complications compared with heparin, but have yielded no apparent long-term benefit. The use of the antiplatelet drug ticlopidine is increasing, although long-term data are lacking. A great deal of recent interest has focused on newer antiplatelet agents, particularly the glycoprotein IIB/IIIa receptor inhibitor c7E3 Fab. In a large-scale trial, c7E3 significantly reduced the 30-day rate of mortality and cardiac events, and these benefits were maintained at 6 mo. This drug, unlike other antiplatelet agents, inhibits the final common pathway of platelet aggregation, which influences not only acute closure but has lasting effects for at least 6 mo. This may reflect a reduction in restenosis, although this remains to be proven. This article gives a brief overview of the pharmacologic agents available for the prophylaxis and treatment of acute ischemic complications of PTCA. PMID- 9367095 TI - Diminishing impact of in-lab complications. PMID- 9367096 TI - Impact of aorto-coronary graft markers on subsequent graft patency: a retrospective review. AB - The use of aorto-coronary graft markers has not been standard, presumably due to concern about possible adverse effects on subsequent graft patency. Our goal was to determine if there was any increased risk of graft occlusion in patients who received circumferential graft markers at the time of their coronary artery bypass (CAB) surgery. A retrospective review of angiograms was performed for patients with prior CAB. Cohorts with and without graft markers were compared. A total of 405 "unmarked" and 311 "marked" grafts were identified in 335 patients meeting inclusion criteria. Patency is reported in divisions of elapsed time since CAB. Overall patency in the "marked" group (71.1%) was significantly higher than in the "unmarked" group (58.0%, P < 0.001). In this retrospective population, there was no increased risk of graft occlusion in patients who received circumferential graft markers at the time of CAB surgery as compared to those patients who did not. PMID- 9367097 TI - Circumferential aorto-coronary bypass markers revisited. PMID- 9367098 TI - Effect of time interval between two balloon inflations on ischemic preconditioning during coronary angioplasty. AB - Ischemic preconditioning, defined as a reduction in myocardial ischemia caused by repeated brief episodes of coronary occlusions, is observed during percutaneous transluminal balloon angioplasty (PTCA). To elucidate the effects of the length of the interval between consecutive balloon inflations on ischemic preconditioning during PTCA, we examined 62 patients with chronic stable angina (48 males and 14 females; mean age 62 +/- 10 yr). PTCA was performed on the left anterior descending artery lacking in collateral vessels. A 2-min balloon inflation was performed twice and the extent of ST segment elevation in the electrocardiogram and the severity of chest pain (scored from 0 to 10) for each inflation were determined and compared. Patients were divided into three groups according to the interval between the two inflations: 1 min, Group 1; 2 min, Group 2; and 5 min, Group 5. In Groups 2 and 5, ST-segment elevation was significantly decreased during the second balloon inflation, as compared with that during the first inflation (P < 0.01, P < 0.001). A significant decrease was also observed in the severity of chest pain (P < 0.05, P < 0.01). However, Group 1 showed no significant decrease in ST-segment elevation or severity of chest pain between the first and second inflations. ST-segment elevation and chest pain were reduced to a greater extent in Group 5 than in Group 2. Results suggest that an interval of more than 2 min between balloon inflations is required to achieve ischemic preconditioning during PTCA. PMID- 9367099 TI - Time for myocardial preconditioning during coronary angioplasty? PMID- 9367100 TI - Epidemiology of congenital coronary artery anomalies: a coronary arteriography study on a central European population. AB - The anatomical patterns and frequency of occurrence of congenital coronary anomalies (CCA) in a Central European cohort has not yet been studied. The angiographic data of 7,694 consecutive patients undergoing coronary arteriography at the Albert Szent-Gyorgyi Medical University, Szeged, Hungary, from 1984 to 1994 were analyzed. CCA were found in 103 patients (1.34% incidence). Ninety eight of them (95.2%) had anomalies of origin and distribution, and five (4.8%) had coronary artery fistulae. The incidence was the highest for the separate origin of left descending artery and left circumflex from the left sinus of Valsalva (52.42%). Anomalous origin of the left circumflex coronary artery from the right coronary was 8.7% while from the right sinus of Valsalva 18.4%. CCA, which may be associated with potentially serious events, such as ectopic coronary origin from the opposite aortic sinus (1.9%) and single coronary arteries (3.88%), were not frequent. The incidence of CCA in the Central European cohort under study was similar to that of the largest North American study. The anatomic classification presented can be useful from both clinical and surgical standpoints. PMID- 9367101 TI - Prevalence and relevance of coronary artery anomalies. PMID- 9367102 TI - Direct right ventricular puncture for hemodynamic evaluation of a mechanical tricuspid valve prosthesis: a new indication for an old procedure. AB - The advent of transvenous right heart catheterization has relegated direct transthoracic right ventricular puncture largely to the role of "interesting historical footnote." However, in the case of a right ventricle that is "protected" by a mechanical tricuspid valve prosthesis, direct right ventricular puncture represents a reasonable alternative for obtaining accurate hemodynamic information. PMID- 9367103 TI - Combined PTCA and aortic valvuloplasty for acute myocardial infarction complicated by severe aortic stenosis and cardiogenic shock. AB - Percutaneous aortic valvuloplasty (PAV) performed in patients with critical aortic stenosis has been shown to increase aortic valve area, decrease aortic valve gradient, and improve left ventricular function. However, the procedure is limited by rapid restenosis. Aortic valvuloplasty in the setting of critical aortic stenosis with cardiogenic shock can be a life-saving procedure, although morbidity and mortality remain high. We describe a patient with critical aortic stenosis who presented with an acute anterior myocardial infarction treated with primary angioplasty. Despite rapidly achieving patency of the culprit vessel, the patient spiraled into cardiogenic shock, which prompted an emergent PAV. PMID- 9367104 TI - Transcatheter closure of a huge pulmonary arteriovenous fistula with embolization coils. AB - A 46-year-old female with bilateral pulmonary arteriovenous fistulas was treated with Gianturco coil occlusion. The small right lung fistula was closed with a 6 mm coil, whereas the huge left lung fistula was occluded with three coils (one 10 mm and two 8-mm). Angiography 3 d later demonstrated recanalization of the left fistula. Two 8 mm coils were inserted to achieve complete obstruction again. She developed pulmonary infarction in the left lung 2 d later, which recovered without sequelae. We conclude that coil embolization for huge pulmonary arteriovenous fistula is feasible but may result in pulmonary infarction. PMID- 9367105 TI - Coils for pulmonary arteriovenous malformations: cheap and effective. PMID- 9367106 TI - Lack of evidence for improvement in internal mammary graft flow by occlusion of side branch. AB - Coronary steal due to unligated side branches of an internal mammary artery graft has been reported previously. Embolization of these side branches has been shown to result in symptomatic improvement, but objective evidence of improved flow to the coronary artery has been lacking. We studied intracoronary Doppler flow in a patient presenting with symptoms thought to be due to a large unligated side branch of mammary graft. There was no significant change in the mammary flow after balloon occlusion of the side branch. More objective data may be required to routinely prescribe side branch embolization for symptomatic patients with unligated side branches of a mammary graft. PMID- 9367107 TI - Successful intracoronary thrombolysis in cocaine-associated acute myocardial infarction. AB - We describe a case of cocaine-associated acute myocardial infarction managed by cardiac catheterization and intracoronary thrombolysis. Based on this and other reported cases, it appears that an invasive approach to the management of cocaine associated acute myocardial infarction is advantageous over intravenous thrombolysis. Such a strategy would define the pathophysiology of acute myocardial infarction in the setting of cocaine use and allow mechanical intervention should pharmacologic therapy be unsuccessful. PMID- 9367108 TI - Atresia of internal thoracic artery grafts following placement to noncritically obstructed vessels. AB - Four patients postcoronary bypass surgery, utilizing the left internal thoracic artery as a jump graft, were found to have atresia of either the proximal segment (2 patients) or the distal interposition segment (2 patients) of this graft. In all 4 cases the atretic portion of the graft was the segment that had been anastomosed to a noncritically obstructed vessel. The segment anastomosed to the severely narrowed portion of the vessel functioned normally and approximated the target vessel size. PMID- 9367109 TI - Coronary artery aneurysms detected with ultrafast computed tomography. AB - A 25-year-old Japanese woman was admitted due to acute inferior myocardial infarction. Coronary angiography showed complete occlusion of the proximal right coronary artery and vague calcification distal to the complete occlusion. Using ultrafast computed tomography, two coronary artery aneurysms in the right coronary artery that could not be detected by coronary angiography were visualized. PMID- 9367110 TI - Catheter-induced acute aortic insufficiency with hemodynamic collapse during PTCA: an unreported complication. AB - Primary PTCA as a means of reestablishing coronary blood flow in the infarct related artery is preferable in certain subgroups of patients with acute myocardial infarction. While the success rate of primary PTCA is very high, the procedure is not without risk. We report a case of hemodynamic collapse during PTCA due to an Amplatz guide catheter-induced, acute, and reversible aortic insufficiency. With the increasing use of the left Amplatz catheter for better guide support during PTCA, this unusual and previously unreported complication should be borne in mind. PMID- 9367111 TI - Anomalous origin of the right coronary artery from the left anterior descending coronary artery. AB - A 77-year-old male presented with a recent posterior myocardial infarction for coronary angiography. This angiogram revealed a rare, previously unreported anomalous origin of the right coronary artery from the proximal left anterior descending coronary artery distal to the first major diagonal branch. PMID- 9367112 TI - Retrieval of detached coating of a hydrophilic guidewire from the profunda femoris artery using an Amplatz gooseneck snare. AB - We present a case where during accidental puncture of the profunda femoris artery the plastic coating of a hydrophilic guidewire was stripped off against the bevel of a metal needle. This lay coiled in the profunda femoris artery. It was retrieved using an Amplatz gooseneck snare from an ipsilateral antegrade common femoral artery puncture. PMID- 9367113 TI - Local heparin delivery prior to coronary stent implantation: acute and six-month clinical and angiographic results. AB - Stents increase smooth muscle cell proliferation, which may also lead to in-stent restenosis. A local delivery strategy provides higher drug concentration at the angioplasty site and may limit the proliferative response following stenting. Local heparin delivery was attempted in 35 patients following balloon angioplasty using an "over-the-balloon" style catheter (infusion sleeve). The infusion sleeve was successfully tracked and heparin was delivered in 33 (94%) patients. Heparin (1,000 IU/ml) was delivered under low (45 psi, 2 ml, n = 4), intermediate (75 psi, 4 ml, n = 11), and high (100 psi, 4 ml, n = 18) proximal infusion pressures. Stent placement was successful in all cases. Acute and in-hospital complications were a severe arterial spasm after heparin delivery, a non Q-wave myocardial infarction, and two vascular complications. Ten dissections were observed after PTCA and prior to heparin delivery. Of these dissections, 7 remained unchanged, 2 worsened, and 1 improved with local delivery. When heparin was delivered in the absence of dissection, no new dissections were observed. Of the 33 patients who received heparin, 30 (91%) had no symptoms and a negative exercise test at clinical follow-up. QCA analysis of 6-month follow-up angiograms, performed in 32 of 33 (97%) patients, demonstrated an acute gain of 1.98 +/- 0.67 mm, a late loss of 0.94 +/- 0.78 mm, a net gain of 1.04 +/- 0.78 mm, and a loss index of 0.48 +/- 0.32. Restenosis (> or = 50% stenosis) was observed in 4 of 32 (12%) patients. Local delivery of heparin via the infusion sleeve following PTCA and prior to stent deployment is feasible with an acceptable safety profile and a low clinical and angiographic restenosis rate at 6 months. PMID- 9367114 TI - New technique for stent jail: another niche for the rotablator. AB - We report the treatment of a jailed side branch using the Rotablator. Initial attempts at passing various low profile balloons in the jailed branch were unsuccessful. The Rotablator allowed access to the side branch, which was stented with a single Palmaz-Schatz stent, providing excellent angiographic and 9 months follow-up results. PMID- 9367115 TI - Detachment of transluminal extraction catheter cutter head from shaft and successful retrieval. AB - Transluminal extraction catheter atherectomy has been shown to be a clinically effective interventional technique for the treatment of thrombotic degenerative saphenous vein bypass grafts. We will report the first case of detachment of transluminal extraction catheter cutter head from the shaft and its successful retrieval during a saphenous vein bypass graft intervention. PMID- 9367116 TI - Dilatation of congenital valvular aortic stenosis using Inoue balloon. AB - Balloon dilatation of valvular aortic stenosis is often associated with problems of balloon seating across the valve and slippage during performance of dilatation. We describe 2 patients with congenital aortic stenosis who underwent balloon dilatation using the Inoue balloon, which to the best of our knowledge has not been reported earlier. The technique and its advantages and limitations in aortic valve dilatation are discussed. PMID- 9367117 TI - Deployment of a previously embolized, unexpanded, and disarticulated Palmaz Schatz stent. AB - Stent embolization is a rare but acknowledged complication of placement of disarticulated (half) Palmaz-Schatz stents. We report a case in which we diagnosed a previously unrecognized, embolized, undeployed half-stent in the distal LAD, causing slow flow, and then deployed the stent where it lay, resulting in improved flow. The literature on treatment of coronary stent embolization and on cutting and preparing half-stents for deployment is discussed. PMID- 9367118 TI - Tracheobronchial Wallstents for degenerated saphenous vein bypass grafts. AB - The tracheobronchial Wallstent was employed as an endoluminal prosthesis in degenerated saphenous vein bypass grafts in three patients. This Wallstent has unique characteristics that make it potentially useful in patients with vein graft disease. PMID- 9367119 TI - Clinical and angiographic outcome after implantation of a home-made stent for complicated coronary angioplasty. AB - To defray the escalating costs of coronary stenting, we handmade a balloon expandable, stainless steel stent, which after experimental evaluation, was implanted in 156 patients undergoing PTCA complicated by a major dissection. The procedural success rate was 98%. The in-hospital course was characterized by a 1.3% cardiopulmonary mortality and a 4.5% nonfatal myocardial infarction rate, while emergency bypass surgery and early repeat PTCA were necessary in only one patient each (0.6%). Clinical 6-mo follow-up in 150 patients revealed no deaths and no myocardial infarctions, and the event-free survival rate was 82%. Six month control angiography was performed in 93.3% of eligible patients and revealed a restenosis rate of 20%. PMID- 9367120 TI - Effect of low grade radiofrequency heating on arterial vasospasm in the porcine model. AB - Nineteen pigs were studied in order to assess the effect of low grade, radiofrequency-powered, thermal balloon angioplasty on the vasoconstrictor response of peripheral arteries. A mechanical stimulus was used to induce vasospasm. Thermal angioplasty reduced the extent of inducible vasospasm from 79% to 6% compared to nonthermal control inflations, which reduced the vasoconstrictor response from 75% to 60% (P < 0.001). Histologic studies demonstrated that the extent of myocyte necrosis was significantly greater in the thermally treated arteries than in the control vessels (P < 0.01). Thermal balloon angioplasty at 60 degrees C significantly attenuates peripheral arterial vasospasm induced by mechanical trauma in the porcine model. This paralytic effect may be related to the loss of myocytes secondary to thermal necrosis. PMID- 9367121 TI - Spontaneous coronary artery dissection: successful results. PMID- 9367122 TI - Protein data representation and query using optimized data decomposition. AB - MOTIVATION: To provide data management tools to maintain and query efficiently experimental and derived protein data with the goal of providing new insights into structure-function relationships. The tools should be portable, extensible, and accessible locally, or via the World Wide Web, providing data that would not otherwise be available. RESULTS: The initial phase of the work, the data representation and query of all available macromolecular structure data, including real-time access to complex property patterns based on the amino acid sequence, is reported. protein structure data taken from the Protein Data Bank (PDB) are decomposed into native and derived elementary properties, and represented as compact indexed objects minimizing storage requirements and query time for select types of query. In addition, collections of indices representing a particular property are maintained and can be queried for specific property patterns found across the whole database. The approach is proving applicable to a wide variety of data available on specific protein families. PMID- 9367123 TI - Bi-dimensional scaling map (BDS-Map): an approach for building large genetic maps. AB - MOTIVATION: The approaches usually used for building large genetic maps consist of dividing the marker set into linkage groups and provide local orders that can be tested by multi-point linkage analysis. To deal with the limitations of these approaches, a strategy taking the marker set into account globally is defined. RESULTS: The paper presents a new approach called 'Bi-Dimensional Scaling Map (BDS-Map) for inferring marker orders and distances in genetic maps based on the use of an additional dimension orthogonal to the map into which markers are projected. Dynamical forces based on a two-point analysis are applied to tend to optimize the marker locations in space. The efficiency of the approach is exemplified on real data (16 and 70 markers on chromosomes 6 and 2, respectively) and simulated data (50 maps of 70 markers). PMID- 9367124 TI - Efficient discovery of conserved patterns using a pattern graph. AB - MOTIVATION: We have previously reported an algorithm for discovering patterns conserved in sets of related unaligned protein sequences. The algorithm was implemented in a program called Pratt. Pratt allows the user to define a class of patterns (e.g. the degree of ambiguity allowed and the length and number of gaps), and is then guaranteed to find the conserved patterns in this class scoring highest according to a defined fitness measure. In many cases, this version of Pratt was very efficient, but in other cases it was too time consuming to be applied. Hence, a more efficient algorithm was needed. RESULTS: In this paper, we describe a new and improved searching strategy that has two main advantages over the old strategy. First, it allows for easier integration with programs for multiple sequence alignment and data base search. Secondly, it makes it possible to use branch-and-bound search, and heuristics, to speed up the search. The new search strategy has been implemented in a new version of the Pratt program. PMID- 9367125 TI - FPC: a system for building contigs from restriction fingerprinted clones. AB - MOTIVATION: To meet the demands of large-scale sequencing, thousands of clones must be fingerprinted and assembled into contigs. To determine the order of clones, a typical experiment is to digest the clones with one or more restriction enzymes and measure the resulting fragments. The probability of two clones overlapping is based on the similarity of their fragments. A contig contains two or more overlapping clones and a minimal tiling path of clones is selected to be sequenced. Interactive software with algorithmic support is necessary to assemble the clones into contigs quickly. RESULTS: FPC (fingerprinted contigs) is an interactive program for building contigs from restriction fingerprinted clones. FPC uses an algorithm to cluster clones into contigs based on their probability of coincidence score. For each contig, it builds a consensus band (CB) map which is similar to a restriction map; but it does not try to resolve all the errors. The CB map is used to assign coordinates to the clones based on their alignment to the map and to provide a detailed visualization of the clone overlap. FPC has editing facilities for the user to refine the coordinates and to remove poorly fingerprinted clones. Functions are available for updating an FPC database with new clones. Contigs can easily be merged, split or deleted. Markers can be added to clones and are displayed with the appropriate contig. Sequence-ready clones can be selected and their sequencing status displayed. As such, FPC is an integrated program for the assembly of sequence-ready clones for large-scale sequencing projects. PMID- 9367126 TI - Estimation of equilibrium constants using automated group contribution methods. AB - MOTIVATION: Group contribution methods are frequently used for estimating physical properties of compounds from their molecular structures. An algorithm for estimating Gibbs energies of formation through group contribution methods has been automated in an object-oriented framework. The algorithm decomposes compound structures according to a basis set of groups. It permits the use of wildcards and is able to distinguish between ring groups and chain groups that use similar search structures. Past methods relied on manual decomposition of compounds into constituent groups. RESULTS: The software is written in Common LISP and requires < 2 min to estimate Gibbs energies of formation for a database of 780 species of varying size and complexity. The software allows rapid expansion to incorporate different basis sets and to estimate a variety of other physical properties. PMID- 9367127 TI - Seqalert--a daily sequence alertness server for the EMBL and SWISSPROT databases. AB - MOTIVATION: The aims were to: enable users to deposit complex search profiles against the sequence databases; interface to an independent Sequence Retrieval System (SRS) server through the network to perform these searches on a daily basis through the last day's updates of these databases; mail users the reformatted search results, enabling local usage when loaded by a WWW browser. RESULTS: The deposition of one to many search profiles by the user leads to a daily search of the EMBL and SWISSPROT databases. The search profile is restricted to entries that were deposited during the last 24 h by using the SRS query manager to combine search sets. If the search is successful, the resulting html page is modified from relative URLs to absolute ones, enabling local usage by loading from disk. The results are sent to the user by e-mail. PMID- 9367128 TI - Compression of nucleotide databases for fast searching. AB - MOTIVATION: International sequencing efforts are creating huge nucleotide databases, which are used in searching applications to locate sequences homologous to a query sequence. In such applications, it is desirable that databases are stored compactly, that sequences can be accessed independently of the order in which they were stored, and that data can be rapidly retrieved from secondary storage, since disk costs are often the bottleneck in searching. RESULTS: We present a purpose-built direct coding scheme for fast retrieval and compression of genomic nucleotide data. The scheme is lossless, readily integrated with sequence search tools, and does not require a model. Direct coding gives good compression and allows faster retrieval than with either uncompressed data or data compressed by other methods, thus yielding significant improvements in search times for high-speed homology search tools. PMID- 9367129 TI - PAML: a program package for phylogenetic analysis by maximum likelihood. PMID- 9367130 TI - GSC: a graphical program for NMR chemical shift comparison. PMID- 9367131 TI - PSeq-Gen: an application for the Monte Carlo simulation of protein sequence evolution along phylogenetic trees. PMID- 9367132 TI - A platform-independent graphical user interface for SEQSEE and XALIGN. PMID- 9367133 TI - MACS: automatic counting of objects based on shape recognition. PMID- 9367134 TI - National Diabetes Awareness Month -- November 1997. PMID- 9367135 TI - Trends in the prevalence and incidence of self-reported diabetes mellitus -- United States, 1980-1994. AB - Diabetes mellitus is associated with severe microvascular complications (e.g., kidney disease and eye disease) and macrovascular complications (e.g., stroke and ischemic heart disease). These complications can result in severe long-term complications (e.g., amputation, disability, and blindness) and account for a substantial economic burden. This report uses data from CDC's National Health Interview Survey (NHIS) to examine trends in the incidence and prevalence of self reported diabetes in the United States during 1980-1994. The findings document increases in both the incidence and prevalence of diabetes during this period and suggest that most of the increase was attributable to factors other than the aging of the U.S. population. PMID- 9367136 TI - Diabetes-specific preventive-care practices among adults in a managed-care population -- Colorado, Behavioral Risk Factor Surveillance System, 1995. AB - The prevalence of diagnosed diabetes in the United States is 3%; however, diabetes accounts for approximately 15% of total U.S. health-care expenditures. Preventive-care practices (e.g., glycemic control and regular foot and ophthalmic examinations) can reduce the occurrence and progression of diabetic complications. Although managed-care organizations (MCOs) have assessed the use of such practices through chart reviews, telephone surveys of MCO patients with diabetes are a less expensive method for collecting accurate data. The ongoing, state-based Behavioral Risk Factor Surveillance System (BRFSS) telephone survey can be used to assess levels of care provided by MCOs and self-care practices among persons with diabetes in MCO populations. In 1995, a Colorado-based MCO collaborated with the Colorado Diabetes Control Program (CDCP) to use the state based BRFSS to assess care practices among MCO enrollees. This report presents findings from the CDCP analysis of data on MCO enrollees aged > or = 30 years who had diabetes; the findings indicate that, although approximately three fourths of enrollees reported most preventive-care practices, two thirds had never heard the term hemoglobin "A-one-C," one fourth had not had their feet examined during the preceding year, and nearly one fifth did not receive an annual dilated-eye examination. PMID- 9367137 TI - Preventive-care knowledge and practices among persons with diabetes mellitus -- North Carolina, Behavioral Risk Factor Surveillance System, 1994-1995. AB - Diabetes mellitus is the leading cause of lower-extremity amputation, end-stage renal disease, and blindness among persons aged 18-65 years in the United States. Diabetes preventive care resulting in improved self-care, better glycemic control, and regular foot and eye examinations can substantially reduce the complications of diabetes. Assessment of the level of preventive care among persons with diabetes can assist in targeting public health efforts to reduce complications. To estimate the prevalence of diabetes and the levels of preventive-care knowledge and practices among persons with diabetes in North Carolina, the North Carolina Office of Epidemiology and the state Diabetes Control Program (DCP), in collaboration with CDC, analyzed data from the Behavioral Risk Factor Surveillance System (BRFSS) for 1994-1995. This report summarizes the results of that analysis, which indicate a low level of diabetes preventive-care knowledge and practices among persons with diabetes in North Carolina. PMID- 9367138 TI - Availability of diabetes information on the Internet. PMID- 9367139 TI - British study will assess risks of vCJD blood transmission. PMID- 9367140 TI - US panel proposes joint 'pathogens initiative'. PMID- 9367141 TI - Largest-ever study contests radiation role in childhood cancers. PMID- 9367142 TI - 'Mind body' claims put NIH on defensive. PMID- 9367143 TI - India drafts law to protect bioresources. PMID- 9367144 TI - Alphabetical listing. PMID- 9367145 TI - Headless tadpoles and an informed public. PMID- 9367146 TI - Getting rid of mosquitoes. PMID- 9367147 TI - Apoptosis. A Bad kinase makes good. PMID- 9367148 TI - Human evolution. Ecce homo--behold mankind. PMID- 9367149 TI - Inositol lipid pathways turn turtle. PMID- 9367150 TI - Saccades without eye movements. PMID- 9367151 TI - A new symmetrodont mammal from China and its implications for mammalian evolution. AB - A new symmetrodont mammal has been discovered in the Mesozoic era (Late Jurassic or Early Cretaceous period) of Liaoning Province, China. Archaic therian mammals, including symmetrodonts, are extinct relatives of the living marsupial and placental therians. However, these archaic therians have been mostly documented by fragmentary fossils. This newfossil taxon, represented by a nearly complete postcranial skeleton and a partial skull with dentition, is the best-preserved symmetrodont mammal yet discovered. It provides a new insight into the relationships of the major lineages of mammals and the evolution of the mammalian skeleton. Our analysis suggests that this new taxon represents a part of the early therian radiation before the divergence of living marsupials and placentals; that therians and multituberculates are more closely related to each other than either group is to other mammalian lineages; that archaic therians lacked the more parasagittal posture of the forelimb of most living therian mammals; and that archaic therians, such as symmetrodonts, retained the primitive feature of a finger-like promontorium (possibly with a straight cochlea) of the non-therian mammals. The fully coiled cochlea evolved later in more derived therian mammals, and is therefore convergent to the partially coiled cochlea of monotremes. PMID- 9367152 TI - Mice lacking bombesin receptor subtype-3 develop metabolic defects and obesity. AB - Mammalian bombesin-like peptides are widely distributed in the central nervous system as well as in the gastrointestinal tract, where they modulate smooth muscle contraction, exocrine and endocrine processes, metabolism and behaviour. They bind to G-protein-coupled receptors on the cell surface to elicit their effects. Bombesin-like peptide receptors cloned so far include, gastrin-releasing peptide receptor (GRP-R), neuromedin B receptor (NMB-R), and bombesin receptor subtype-3 (BRS-3). However, despite the molecular characterization of BRS-3, determination of its function has been difficult as a result of its low affinity for bombesin and its lack of an identified natural ligand. We have generated BRS 3-deficient mice in an attempt to determine the in vivo function of the receptor. Mice lacking functional BRS-3 developed a mild obesity, associated with hypertension and impairment of glucose metabolism. They also exhibited reduced metabolic rate, increased feeding efficiency and subsequent hyperphagia. Our data suggest that BRS-3 is required for the regulation of endocrine processes and metabolism responsible for energy balance and adiposity. BRS-3-deficient mice provide a useful new model for the investigation of human obesity and associated diseases. PMID- 9367153 TI - Math1 is essential for genesis of cerebellar granule neurons. AB - The cerebellum is essential for fine motor control of movement and posture, and its dysfunction disrupts balance and impairs control of speech, limb and eye movements. The developing cerebellum consists mainly of three types of neuronal cells: granule cells in the external germinal layer, Purkinje cells, and neurons of the deep nuclei. The molecular mechanisms that underlie the specific determination and the differentiation of each of these neuronal subtypes are unknown. Math1, the mouse homologue of the Drosophila gene atonal, encodes a basic helix-loop-helix transcription factor that is specifically expressed in the precursors of the external germinal layer and their derivatives. Here we report that mice lacking Math1 fail to form granule cells and are born with a cerebellum that is devoid of an external germinal layer. To our knowledge, Math1 is the first gene to be shown to be required in vivo for the genesis of granule cells, and hence the predominant neuronal population in the cerebellum. PMID- 9367154 TI - Impaired mast cell-dependent natural immunity in complement C3-deficient mice. AB - The complement system is widely regarded as essential for normal inflammation, not least because of its ability to activate mast cells. However, recent studies have called into question the importance of complement in several examples of mast cell-dependent inflammatory responses. To investigate the role of complement in mast cell-dependent natural immunity, we examined the responses of complement deficient mice to caecal ligation and puncture, a model of acute septic peritonitis that is dependent on mast cells and tumour necrosis factor-alpha (TNF alpha). We found that C4- or C3-deficient mice were much more sensitive to caecal ligation and puncture than wild-type (WT) controls (100% versus 20% in 24-h mortality, respectively). C3-deficient mice also exhibited reductions in peritoneal mast cell degranulation, production of TNF-alpha, neutrophil infiltration and clearance of bacteria. Treating the C3-deficient mice with purified C3 protein enhanced activation of peritoneal mast cells, TNF-alpha production, neutrophil recruitment, opsonophagocytosis of bacteria and resistance to caecal ligation and puncture, confirming that the defects were complement dependent. These results provide formal evidence that complement activation is essential for the full expression of innate immunity in this mast cell-dependent model of bacterial infection. PMID- 9367155 TI - A homologue of the TNF receptor and its ligand enhance T-cell growth and dendritic-cell function. AB - Dendritic cells are rare haematopoietic cells that reside in a number of organs and tissues. By capturing, processing and presenting antigens to T cells, dendritic cells are essential for immune surveillance and the regulation of specific immunity. Several members of the tumour necrosis factor receptor (TNFR) superfamily are integral to the regulation of the immune response. These structurally related proteins modulate cellular functions ranging from proliferation and differentiation to inflammation and cell survival or deaths. The functional activity of dendritic cells is greatly increased by signalling through the TNFR family member CD40. Here we report the characterization of RANK (for receptor activator of NF-kappaB), a new member of the TNFR family derived from dendritic cells, and the isolation of a RANK ligand (RANKL) by direct expression screening. RANKL augments the ability of dendritic cells to stimulate naive T-cell proliferation in a mixed lymphocyte reaction, and increases the survival of RANK+ T cells generated with interleukin-4 and transforming growth factor (TGF)-beta. Thus RANK and RANKL seem to be important regulators of interactions between T cells and dendritic cells. PMID- 9367156 TI - DAP kinase links the control of apoptosis to metastasis. AB - DAP kinase is a new type of calcium/calmodulin-dependent enzyme that phosphorylates serine/threonine residues on proteins. Its structure contains ankyrin repeats and the 'death' domain, and it is associated with the cell cytoskeleton. The gene encoding DAP kinase was initially isolated as a positive mediator of apoptosis induced by interferon-gamma, by using a strategy of functional cloning. We have now tested whether this gene has tumour-suppressive activity. We found that lung carcinoma clones, characterized by their highly aggressive metastatic behaviour and originating from two independent murine lung tumours, did not express DAP kinase, in contrast to their low-metastatic counterparts. Restoration of DAP kinase to physiological levels in high metastatic Lewis carcinoma cells suppressed their ability to form lung metastases after intravenous injection into syngeneic mice, and delayed local tumour growth in a foreign 'microenvironment' Conversely, in vivo selection of rare lung lesions following injection into syngeneic mice of low-metastatic Lewis carcinoma cells or of DAP kinase transfectants, was associated with loss of DAP kinase expression. In situ TUNEL staining of tumour sections revealed that DAP kinase expression from the transgene raised the incidence of apoptosis in vivo. DAP kinase transfectants also showed increased sensitivity in vitro to apoptotic stimuli, of the sort encountered by metastasizing cells at different stages of malignancy. We propose that loss of DAP kinase expression provides a unique mechanism that links suppression of apoptosis to metastasis. PMID- 9367157 TI - Herpes viral cyclin/Cdk6 complexes evade inhibition by CDK inhibitor proteins. AB - The passage of mammalian cells through the restriction point into the S phase of the cell cycle is regulated by the activities of Cdk4 and Cdk6 complexed with the D-type cyclins and by cyclin E/Cdk2. The activities of these holoenzymes are constrained by CDK inhibitory proteins. The importance of the restriction point is illustrated by its deregulation in many tumour cells and upon infection with DNA tumour viruses. Here we describe the properties of cyclins encoded by two herpesviruses, herpesvirus saimiri (HVS) which can transform blood lymphocytes and induce malignancies of lymphoid origin in New World primates, and human herpesvirus 8 (HHV8) implicated as a causative agent of Kaposi's sarcoma and body cavity lymphomas. Both viral cyclins form active kinase complexes with Cdk6 that are resistant to inhibition by the CDK inhibitors p16(Ink4a), p21Cip1 and p27Kip1. Furthermore, ectopic expression of a viral cyclin prevents G1 arrest imposed by each inhibitor and stimulates cell-cycle progression in quiescent fibroblasts. These results suggest a new mechanism for deregulation of the cell cycle and indicate that the viral cyclins may contribute to the oncogenic nature of these viruses. PMID- 9367158 TI - Osmotic stress activates phosphatidylinositol-3,5-bisphosphate synthesis. AB - Inositol phospholipids play multiple roles in cell signalling systems. Two widespread eukaryotic phosphoinositide-based signal transduction mechanisms, phosphoinositidase C-catalysed phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) hydrolysis and 3-OH kinase-catalysed PtdIns(4,5)P2 phosphorylation, make the second messengers inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) sn-1,2-diacylglycerol and PtdIns(3,4,5)P3. In addition, PtdIns(4,5)P2 and PtdIns3P have been implicated in exocytosis and membrane trafficking. We now show that when the yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe are hyperosmotically stressed, they rapidly synthesize phosphatidylinositol-3,5-bisphosphate (PtdIns(3,5)P2) by a process that involves activation of a PtdIns3P 5-OH kinase. This PtdIns(3,5)P2 accumulation only occurs in yeasts that have an active vps34-encoded PtdIns 3-OH kinase, showing that this latter kinase makes the PtdIns3P needed for PtdIns(3,5)P2 synthesis and indicating that PtdIns(3,5)P2 may have a role in sorting vesicular proteins. PtdIns(3,5)P2 is also present in mammalian and plant cells: in monkey Cos-7 cells, its labelling is inversely related to the external osmotic pressure. The stimulation of a PtdIns3P 5-OH kinase-catalysed synthesis of PtdIns(3,5)P2, a molecule that might be a new type of phosphoinositide 'second messenger, thus appears to be central to a widespread and previously uncharacterized regulatory pathway. PMID- 9367159 TI - A new pathway for synthesis of phosphatidylinositol-4,5-bisphosphate. AB - Phosphatidylinositol-4,5-bisphosphate (PtdIns-4,5-P2), a key molecule in the phosphoinositide signalling pathway, was thought to be synthesized exclusively by phosphorylation of PtdIns-4-P at the D-5 position of the inositol ring. The enzymes that produce PtdIns-4,5-P2 in vitro fall into two related subfamilies (type I and type II PtdInsP-5-OH kinases, or PIP(5)Ks) based on their enzymatic properties and sequence similarities'. Here we have reinvestigated the substrate specificities of these enzymes. As expected, the type I enzyme phosphorylates PtdIns-4-P at the D-5 position of the inositol ring. Surprisingly, the type II enzyme, which is abundant in some tissues, phosphorylates PtdIns-5-P at the D-4 position, and thus should be considered as a 4-OH kinase, or PIP(4)K. The earlier error in characterizing the activity of the type II enzyme is due to the presence of contaminating PtdIns-5-P in commercial preparations of PtdIns-4-P. Although PtdIns-5-P was previously thought not to exist in vivo, we find evidence for the presence of this lipid in mammalian fibroblasts, establishing a new pathway for PtdIns-4,5-P2 synthesis. PMID- 9367160 TI - Folding dynamics and mechanism of beta-hairpin formation. AB - Protein chains coil into alpha-helices and beta-sheet structures. Knowing the timescales and mechanism of formation of these basic structural elements is essential for understanding how proteins fold. For the past 40 years, alpha-helix formation has been extensively investigated in synthetic and natural peptides, including by nanosecond kinetic studies. In contrast, the mechanism of formation of beta structures has not been studied experimentally. The minimal beta structure element is the beta-hairpin, which is also the basic component of antiparallel beta-sheets. Here we use a nanosecond laser temperature-jump apparatus to study the kinetics of folding a beta-hairpin consisting of 16 amino acid residues. Folding of the hairpin occurs in 6 micros at room temperature, which is about 30 times slower than the rate of alpha-helix formation. We have developed a simple statistical mechanical model that provides a structural explanation for this result. Our analysis also shows that folding of a beta hairpin captures much of the basic physics of protein folding, including stabilization by hydrogen bonding and hydrophobic interactions, two-state behaviour, and a funnel-like, partially rugged energy landscape. PMID- 9367161 TI - In defence of small science. PMID- 9367162 TI - Molecular cloning of the porcine beta-1,2-N-acetylglucosaminyltransferase II gene and assignment to chromosome 1q23-q27. AB - Glycosyltransferases play an important role in the synthesis of glycoproteins. Here we report the isolation of a brain cDNA coding for 89% of the porcine UDP-N acetylglucosamine:alpha-6-D-mannoside-beta-1,2-N-acetylglucosaminy ltransferase II (EC 2.4.1.143) (GnTII). The cDNA was used for screening a genomic liver DNA library and isolation of a recombinant lambda FIX II phage containing the complete porcine GnTII gene and upstream and downstream sequences. The beta-1,2-N acetylglucosaminyltransferase II gene harbours a single exon with an open reading frame of 1338 bp coding for a 446 amino acid protein with a calculated molecular mass of 51.1 kDa. The promoter of the GnTII gene is lacking a TATA-box and shows variable transcription start sites. In the 3'-untranslated region a polymorphic polyadenosine stretch was detected. The porcine GnTII gene contains four polyadenylation sites. PCR analysis of a porcine-rodent hybrid cell panel revealed the chromosomal location of the GnTII gene on SSC 1q23-q27. The mapping data of the cell panel were confirmed by fluorescence in situ hybridization (FISH) on metaphase chromosomes. PMID- 9367163 TI - Human salivary histatin-5 exerts potent fungicidal activity against Cryptococcus neoformans. AB - Human salivary histatins (Hsns) have been known to be potent antifungal agents against Candida albicans for more than a decade. Here, we report that Hsns are also effective in killing another medically important opportunistic fungal pathogen, Cryptococcus neoformans, which has become a new threat among the immunocompromised patients, especially AIDS patients. In fact, the cidal activity of Hsn-5 against C. neoformans is as high as that against C. albicans. PMID- 9367164 TI - Biochemical characterization of the subunits of the Na+/K+ ATPase expressed in insect cells. AB - The Na+/K+ ATPase is composed of two subunits called alpha and beta chains. In insect cells, independently expressed alpha and beta chains are localized to intracellular membranes. Sucrose density gradient sedimentation, crosslinking analysis, and immunoprecipitation of radio-labeled proteins show that the alpha chains expressed alone are in large aggregates of different molecular weights with less than 4% being monomeric. Analysis by non-reducing SDS-PAGE and immunoblotting show that the beta chains expressed alone are in Triton X-100 insoluble, disulfide-linked aggregates. Co-expression of both subunits in insect cells results in only a small fraction (less than 15%) of the alpha chains being assembled as the active recombinant enzyme, with at least 22% of the active recombinant enzyme localized to the plasma membrane as determined by a biochemical assay. The small amount of beta chain at the plasma membrane in cells that express both subunits is beyond the limit of detection by the biochemical assay. Immunoprecipitation of Triton X-100 soluble alpha chains from radio labeled cells expressing both subunits shows that the alpha chains are mostly in large aggregates containing beta chains. These results suggest that, in insect cells, the availability of correctly folded beta chains is the rate limiting step in the assembly of active Na+/K+ ATPase. PMID- 9367165 TI - Regulation of cellular phosphorylation of hyaluronan binding protein and its role in the formation of second messenger. AB - The presence of the 34-kDa hyaluronan binding protein, a new member of the 'hyaladherins' family, was demonstrated in a wide variety of cell lines by immunoblot analysis. This protein was observed to be highly phosphorylated in transformed fibroblasts compared to normal fibroblasts. Phosphorylation was enhanced in the presence of its ligand i.e., hyaluronan, but not in the presence of other glycosaminoglycans. The phosphorylated form of this hyaluronan binding protein was shown to be present on the cell surface and could be detected in serum-free medium. The regulation of the cellular and cell surface phosphorylation of HA-binding protein by HA, PMA and calyculin-A was demonstrated in different cell lines. Hyaluronan enhanced the phosphorylation of PLC-gamma in association with increased formation of inositol 1,4,5-triphosphate, both of which were specifically blocked by pretreatment of the cells with purified anti hyaluronan binding protein antibodies. The data presented here indicate a role for the 34-kDa hyaluronan binding protein in cellular signal transduction. PMID- 9367166 TI - Effect of chemical glycosylation of RNase A on the protein stability and surface histidines accessibility in immobilized metal ion affinity electrophoresis (IMAGE) system. AB - Immobilized metal ion affinity gel electrophoresis (IMAGE) has been applied to study the change of the surface histidines topography of RNase A when chemically glycosylated on exposed carboxylic groups with glucosamine using carbodiimide as cross-linker, under mild conditions. Two populations of glycosylated RNase A, one with a single glucosamine and another with two glucosamine attached, were obtained. These chemically glycosylated RNase A conserved about 80% of native enzymatic activity and their pls were increased in comparison to native RNase A. The chemically glycosylated RNase A showed dramatic enhancement for thermal stability, while proteolytic resistance was similar to that of native RNase A. Chemically glycosylated RNase A showed a slightly increased affinity to IDA Cu(II) as compared to the native enzyme, which indicates that a conformational change and/or a decrease in steric hindrance around accessible surface histidines (His 12 or His 119 and His 105) has occured. IMAGE is a useful method to analyse subtle conformational changes in proteins which result in subtle changes in histidine accessibilities. PMID- 9367167 TI - Rat liver ADP-ribose pyrophosphatase-I as an in vitro target of the acetaminophen metabolite N-acetyl-p-benzoquinoneimine. AB - N-acetyl-p-benzoquinoneimine (NAPQI) is the metabolite responsible for acetaminophen hepatotoxicity. ADP-ribose pyrophosphatase-I (ADPRibase-I; EC 3.6.1.13) hydrolyzes protein-glycating ADP-ribose. The results show NAPQI dependent alterations of ADPRibase-I leading to strong inhibition: a fast Km increase produced by low concentrations, and a time-dependent Vmax decrease by higher NAPQI concentrations. Both effects were prevented by thiols, but not reverted by them, nor by gel filtration of NAPQI-treated enzyme. Liver ADPRibase I can be a target of NAPQI-dependent arylation. The inhibition or inactivation of the enzyme would contribute to increasing the free ADP-ribose concentration and nonenzymatic ADP-ribosylation, which is coherent with results linking free ADP ribose-producing pathways to acetaminophen toxicity. PMID- 9367168 TI - Mutual interaction between glycation and oxidation during non-enzymatic protein modification. AB - Aging pathogenesis involves non-enzymatic modifications of proteins; protein oxidation, glycation and their interactions have aroused a particular interest. Possible interrelations between oxidation and glycation have been evaluated in vitro: bovine serum albumin was oxidized by gamma-irradiation and then exposed to in vitro glycation. Fluorescence modifications induced by radiolytic oxidation and glycation were similar and tended to be additive. Both non-enzymatic processes provoked a loss of free sulfhydryl groups and a strong increment of protein carbonyl content: this supports that glycation can act through oxidative mechanisms. The observed rearrangement of amino groups after irradiation could predispose proteins to glycation attacks. Protein peroxides generated during irradiation appear able to give birth to further protein modifications leading to the generation of carbonyl groups and to interact with monosaccharides, probably stimulating their autoxidation and in turn glycative protein damage. Glycation increases the oxidation-mediated structural damage revealed by SDS-PAGE. Therefore our data support the hypothesis of mutual enhancement between oxidation and glycation of proteins and suggest possible molecular mechanisms of interactions. PMID- 9367169 TI - Antigenic determination fragments of alpha-momorcharin. AB - Alpha momorcharin is a protein isolated from the bitter gourd. It has a number of biological activities including induction of abortion, inhibition of tumor growth and anti-HIV. All these activities may be related to the ribosome-inhibiting activity of the protein. Repeated use of alphaMMC can elicit an antigenic response which may neutralize its biological activity. To overcome this problem, we need to know which part of the molecule is the antigenic determinant. In this study, we constructed a random fragment expression library from the alphaMMC cDNA and screened it with three anti-alphaMMC sera. A total of 9 positive clones were picked and sequenced. Based on the sequence information obtained, we were able to deduce three regions at which antibodies raised against native alphaMMC seem to interact. These regions are residues 1-14, residues 71-136 and residues 195-222. Mapping of these regions against a 3D model of alphaMMC indicates that they all are located on the surface of the molecule. As residues 71-136 are found to be in close proximity to the active site involved in ribosome inactivation, treatment with a monoclonal antibody directed to this area was shown to be effective in inactivating the inhibitory effect of alphaMMC on in vitro protein synthesis. PMID- 9367170 TI - Purification and characterization of prostate specific antigen from human urine. AB - Prostate specific antigen (uPSA) was purified to homogeneity from human urine using SuperQ-Toyopearl, Sulfate-Cellulofine, Phenyl-Toyopearl, CM-Sepharose, anti urokinase IgG Sepharose and Sephadex G-100. The purified uPSA gave a major band at 32.9 kDa on SDS-PAGE under the reduced condition. However, it shows multiple bands on native PAGE. Substrate specificity of purified uPSA is identical with that of PSA from human seminal plasma and uPSA shows the kallikrein and chymotrypsin-like activities. On the analysis of N-terminal amino acid, two amino acid residues at N-terminal position of uPSA were detected and other amino acid sequence of uPSA was identical with that of sPSA. In addition, we isolated the multiple components of uPSA using anion-exchange chromatography. They were almost the same in amino acid composition and N-terminal amino acid sequences and showed differences in lectin-blotting pattern. PMID- 9367171 TI - The determination of magnesium in human blood plasma by 31P magnetic resonance spectroscopy using a macrocyclic reporter ligand. AB - The ligand 1,4,7-triazacyclononane-1,4,7-tris(methylene methylphosphinic acid), NOTMP, was used to measure free MgII levels in blood plasma by 31P MRS. Separate resonances were observed for the free ligand and the MgII complex and the ratio of their resonance areas was used to evaluate the free, ionized MgII concentration, [Mg]free. The CaII and the ZnII complexes gave rise to separate resonances in the 31P spectrum in an aqueous sample. In human blood plasma samples, however, these resonances were never observed thus excluding the interference of these metal ions. Heparin, up to 150 units/ml, had no influence on the Mg-NOTMP equilibrium. The 31P MRS methodology was applied to twenty human blood plasma samples. Total MgII ([Mg]total), as measured by atomic absorption spectroscopy, averaged 0.85 +/- 0.12 mM while free ionized MgII ([Mg]free) measured by 31P MRS was 0.66 +/- 0.09 mM. The 31P MRS method gave inherently larger values for free ionized MgII than that reported by ion-selective electrodes (ISE). This was traced to a redistribution of existing plasma MgII species after the addition of about 2 mM of NOTMP. Calculations using existing thermodynamic data show that the ionized MgII concentration (iMg) and the concentration of MgII weakly complexed to small anions (Mg(comp)) both drop after the addition of NOTMP, with Mg(comp) dropping to negligible levels. Thus, the 31P MRS method appears to be less sensitive to variations in the concentration of weakly binding anions (bicarbonate, carbonate, chloride, lactate, phosphate, etc.) than the ISE method. Our data indicates that the difference between Mg(total), as measured by atomic absorption spectroscopy, and Mg(free), as measured by 31P MRS, provides an direct estimate of the protein bound MgII fraction. PMID- 9367172 TI - Inhibition of angiogenesis in vitro and in vivo: comparison of the relative activities of triflavin, an Arg-Gly-Asp-containing peptide and anti-alpha(v)beta3 integrin monoclonal antibody. AB - Disintegrin which contains the amino acid sequence Arg-Gly-Asp (RGD), has been implicated as a recognition site in interactions between extracellular matrix (ECM) and cell membrane receptors. Triflavin, a 7.5 kDa cysteine-rich polypeptide purified from Trimeresurus flavoviridis snake venom, belongs to a family of disintegrins. Integrin alpha(v)beta3 has recently been identified as a marker of angiogenic blood vessels and therefore anti-alpha(v)beta3 mAb may significantly inhibit angiogenesis. Therefore, this study was designed to compare the relative activity of triflavin and anti-alpha(v)beta3 mAb in human umbilical vein endothelial cell (HUVEC) adhesion and migration in vitro, and on angiogenesis induced by TNF(alpha) in chicken chorioallantoic membrane (CAM). In this study, it was shown that triflavin (0.1 to 0.4 microM) dose-dependently inhibited the adhesion of HUVECs to ECMs (i.e., vitronectin, fibronectin, laminin and collagen type IV). At a concentration of 10 microM, anti-alpha(v)beta3 mAb almost completely inhibited the adhesion of cells to vitronectin, had a moderate inhibitory effect on fibronectin and laminin, but only a slight inhibitory effect on collagen type IV. On the other hand, vitronectin and fibronectin promote a significantly greater extent of cell adhesion and migration than laminin or collagen type IV over a wide range of concentrations (5 to 15 microg/ml). In cell migration studies, triflavin (0.4 microM) inhibited more markedly vitronectin- and fibronectin-mediated migration than that mediated by laminin- and collagen type IV. Comparison of the relative effectiveness of triflavin with anti alpha(v)beta3 mAb, showed that triflavin was at least twenty to thirty times more potent than anti-alpha(v)beta3 mAb at inhibiting cell adhesion and migration. Furthermore, we used TNF(alpha) as an inducer of angiogenesis in the CAM assay. Close examination of the effects of triflavin and anti-alpha(v)beta3 mAb on TNF(alpha)-induced angiogenesis revealed the presence of discontinuous and disrupted blood vessels. However, anti-alpha(v)beta3 mAb showed a significant effect only at a higher concentration (10 microM). These results suggest that the inhibition of angiogenesis may have been due to interference with the adhesion and migration of endothelial cells to ECMs. The results also indicate that triflavin has a more powerful inhibitory effect than anti-alpha(v)beta3 mAb on angiogenesis, suggesting that triflavin could theoretically be used as a reasonable therapeutic adjuvant for therapy or prevention of angiogenesis-induced diseases. PMID- 9367173 TI - Structural and functional modifications of bovine trypsin by heparins. Influence of heparin molecular mass and structure. AB - Heparins with different structures, charge density and molecular mass were evaluated for their capacity to induce structural and functional alterations of bovine trypsin in a low ionic strength buffer (20 mM Tris-HCl pH 7.4). Unfractionated heparin, and slow and fast moving heparin species increased the fluorescence peak emission of trypsin to the same extent (about +40.0%), whilst partially desulfated and re-N-acetylated heparin with a charge density of 1.47 modified the fluorescence at 330 nm by about +27% and natural heparan sulfate with a sulfate-to-carboxyl ratio < 1 by about +13%. Heparin fractions with narrow polydispersity and the same charge density (produced by chemical depolymerization in the presence of free radicals and further gel-permeation chromatography) having molecular mass lower than about 6000 interact with trypsin to a less extent, even though fractions with molecular mass of about 4500 and 3600 partially retain this property. No modification of fluorescence peak emission of trypsin with heparin was appreciable when the ionic strength of the buffer was increased to 0.3 mM NaCl. An altered ability to reduce cytochrome c was observed for heparins of different charge density; fragments with molecular mass lower than approximately 4000 were also unable to produce superoxide. Trypsin was degraded into fragments by heparin and derivatives after 3 h incubation at 37 degrees C. After electrophoresis in polyacrylamide-gels the trypsin bands disappeared and fragments with lower molecular mass were more evident. This effect depended on the molecular mass of heparin, and was more evident for unfractionated heparin and for a heparin fraction with a molecular mass of 7820. The esterolytic activity of trypsin was inhibited to the same extent by heparin derivatives of various structure and charge density while activity undermet minor changes in the presence of heparin fractions of Mr lower than 4000. PMID- 9367174 TI - Effects of zero magnetic field on the conformation of chromatin in human cells. AB - The effects of zero magnetic field on human VH-10 fibroblasts and lymphocytes were studied by the method of anomalous viscosity time dependencies (AVTD). A decrease of about 20% in the AVTD peaks was observed within 40 to 80 min of exposure of fibroblasts. This decrease was transient and disappeared 120 min after beginning of exposure. Similar kinetics for the effect of zero field was observed when cells were exposed 20 min and then kept at an ambient field. A 20% decrease of the AVTD peaks (p < 0.005 to 0.05) 40 to 70 min after 20 min exposure to zero field was reproduced in four independent experiments (out of four) with human lymphocytes from the same healthy donor. Contrary to the effects of zero field, irradiation of lymphocytes or fibroblasts with gamma-rays resulted in significant increase of the AVTD peaks immediately after irradiation. We concluded that zero field and gamma-rays caused hypercondensation and decondensation of chromatin, correspondingly. The effect of ethidium bromide served as a positive control and supported this conclusion. The effects of zero field on human lymphocytes were more significant in the beginning of G1-phase than in G0-phase. Thus, human fibroblasts and lymphocytes were shown to respond to zero magnetic field. PMID- 9367175 TI - The role of pyruvate dehydrogenase, phosphofructo-1-kinase and acetyl-CoA carboxylase in the regulation of fatty acid synthesis in the lactating rat mammary gland during the starved to re-fed transition. AB - Re-feeding 24-h-starved lactating rats resulted in a rapid (within 0.5 h) restoration of glucose uptake by the mammary gland and a slower (within 3 h) restoration of fatty acid synthesis. The rapid reactivation of glucose uptake (82% of fed value within 0.5 h of re-feeding) correlated with a rapid reactivation of 6-phosphofructo-1-kinase (6-PF-1-K) and glycolysis (as determined by a 97% decrease in the [fructose-6-phosphate]/[fructose-1,6-bisphosphate] ratio). This could not be fully explained by a fall (29%) in the tissue concentration of its allosteric inhibitor, citrate. The delayed reactivation of pyruvate dehydrogenase (PDH) correlated very closely with the delayed reactivation of fatty acid synthesis and explained the continued output of pyruvate and lactate within the first 0.5 h of re-feeding. PDH reactivation preceded the reactivation of acetyl-CoA carboxylase (ACC), which did not occur significantly until 1.5 h of re-feeding. ACC reactivation correlated with a decrease in the tissue concentration of citrate and a second late phase of 6-PF-1 K activation. It is clear that the important regulatory steps 6-PF-1-K, PDH and ACC, are reactivated asynchronously in the lactating mammary gland in response to re-feeding starved rats and that PDH is more important than ACC in the regulation of fatty acid synthesis. PMID- 9367176 TI - Synthesis, physical and biological properties of lithocholyl-lysyl-fluorescein: a fluorescent monohydroxy bile salt analogue with cholestatic properties. AB - We have synthesised and characterised a fluorescent monohydroxy bile salt analogue, lithocholyl-lysyl-fluorescein and compared its physical and biological properties with those of lithocholate, glycolithocholate, sulpholithocholate, lithocholic acid glucuronide and taurocholate. The synthetic method used excess N epsilon-CBZ-L-lysine methyl ester hydrochloride and lithocholic acid via N ethoxycarbonyl-2-ethoxy-1,2-dihydroquinolone (EEDQ) to give lithocholyl-lysine. Lithocholyl-lysyl-fluorescein (LLF) was then prepared using equimolar amounts of lithocholyl-lysine and fluorescein isothiocyanate (FITC) in bicarbonate buffer. LLF retained an apple green fluorescence, similar to that of fluorescein. Unlike lithocholate, the critical micellar concentrations (CMCs) of LLF, glycolithocholate (GLC), lithocholic acid glucuronide (LG) and sulpholithocholic acid (SLC) were similar. HPLC retention times (tRs) of LLF and GLC were similar with a ratio of LLF/GLC of 1.05. In contrast, the tR of SLC (6.52 min) but not of LG (21.2 min) was more comparable to that of taurocholate (5.73 min). In rats under pentobarbital anaesthesia, the plasma half-life (t(1/2alpha)) (min) was 4.5 +/- 1.3 (n = 6) for LLF, 2.9 +/- 0.4 (n = 5) for [14C]sulpholithocholate (14C SLC) and 4.3 +/- 0.3 (min) for [14C]lithocholic acid glucuronide (14C-LG). Plasma clearances of 14C-SLC, LLF and 14C-LG were 15.5 +/- 2.2 (n = 6), 18.1 +/- 4.2 (n = 6) and 17.8 +/- 0.5 ml/min/kg (n = 6) (P = 0.15), respectively. Biliary excretion in bile-fistula rats gave cumulative 20 min biliary output as a percentage of injected dose as follows: LLF, 71.6 +/- 0.8% (n = 10); 14C-SLC, 75.5 +/- 2.8% (n = 6) and 14C-LG, 61.7 +/- 0.5% (n = 6) (P = NS). Peak biliary excretion rates, given as % dose/2 min, were 10.2 +/- 0.3 for LLF, 13.5 +/- 0.6 for 14C-SLC and 12.8 +/- 0.4 for 14C-LG. In another group of bile-fistula rats, a 3.0 micromol/500 microl saline i.v. bolus of LLF caused a 15.4 +/- 1.9% decrease in bile flow and, similarly, sodium lithocholate in a solution of albumin caused a 17.9 +/- 1.8% (P = NS) diminution in bile flow. Despite the similar cholestatic properties of LLF and lithocholate, LLF was more soluble than lithocholate, with a relative retention time on HPLC similar to that of GLC. LLF is a divalent 'unipolar' anionic fluorescent monohydroxy bile salt analogue with physical, biological and cholestatic properties that are similar to those of lithocholate, glycolithocholate and their derivatives and thus offers a potentially useful probe for studying mechanisms of monohydroxy bile salt-induced cholestasis at the hepatocellular level. PMID- 9367177 TI - Kinetics of heme interaction with heme-binding proteins: the effect of heme aggregation state. AB - The kinetics of the interaction of heme with hemopexin and albumin was monitored by measuring the time dependence of changes in the Soret absorption spectra. Since the protein binding sites can only bind heme monomers, the binding kinetics apparently reflected the slow dissociation of heme dimers, resulting from dimer/monomer equilibria in aqueous heme solutions. The dissociation of heme dimers is characterized by the rate constant of (3-4) x 10(-3) s(-1). The measurements further revealed significant differences in the kinetic profiles (slowing down the binding interaction) that were dependent on the storage time of heme solutions at room temperature. These presumably responded to the gradual formation of higher aggregates of heme, which cannot dissociate into dimers/monomers. Alternatively, partial autooxidation of heme molecules could increase the stability of heme dimers and obstruct specific binding of heme to the proteins. PMID- 9367178 TI - Nitric oxide formation from hydroxylamine by myoglobin and hydrogen peroxide. AB - Hydroxylamine (HA), which is a natural product of mammalian cells, has been shown to possess vasodilatory properties in several model systems. In this study, HA and methyl-substituted hydroxylamines, N-methylhydroxylamine (NMHA) and N,N dimethylhydroxylamine (NDMHA), have been tested for their ability to generate free diffusible nitric oxide (NO) in the presence of myoglobin (Mb) and hydrogen peroxide. A NO-specific conversion of 2-(4-carboxyphenyl)-4,4,5,5 tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO) to 2-(4-carboxyphenyl) 4,4,5,5-tetramethylimidazoline-1-oxyl (carboxy-PTI), measured by electron spin resonance (ESR) spectroscopy, along with nitrite and nitrate production, was observed for HA but not for NMHA and NDMHA. ESR measurements at 77 K showed the formation of the ferrous nitrosyl myoglobin, Mb-NO, in the reaction mixtures containing Mb, H2O2 and HA. Our data also demonstrate that Mb-NO is an end product of the reaction pathway involving Mb, H2O2 and HA, rather than a reaction intermediate in the formation of NO. In summary, our results demonstrate a possible pathway of NO formation from HA, however, the significance of this mechanism for bioactivation of HA in vivo is unknown at the present time. PMID- 9367179 TI - The inhibitory action of fatty acids on DNA polymerase beta. AB - We found previously that long-chain fatty acids could inhibit eukaryotic DNA polymerase activities in vitro [1,2]. The purpose of the present study was to investigate the mode of this inhibition in greater detail. Among the C18 to C24 fatty acids examined, the strongest inhibitor was a C24 fatty acid, nervonic acid (NA), and the weakest was a C18 fatty acid, linoleic acid (LA). We analyzed the inhibitory effect of these two fatty acids and their modes of action. For DNA polymerase beta (pol. beta), NA acted by competing with both the substrate- and template-primer, but for DNA polymerase alpha (pol. alpha) or human immunodeficiency virus type 1 reverse transcriptase (HIV-1 reverse transcriptase or HIV-RT), NA acted non-competitively. NA-binding to pol. beta could be stopped with a non-ionic detergent, but the binding to pol. alpha or HIV-RT could not. The inhibition mode of LA showed the same characteristics, except that the minimum inhibitory dose of the longer chain was much lower. We also tested the effects of NA and LA using pol. beta and its proteolytic fragments, as described by Kumar et al. [3,4]. Both of the fatty acids were found to bind to the 8 kDa DNA-binding domain fragment, and to suppress binding to the template-primer DNA. We found that 10,000 times more of either fatty acid was required for it to bind to the 31 kDa catalytic domain or inhibit the DNA polymerase activity. The possible modes of inhibition by these long-chain fatty acids are discussed, based on the present findings. PMID- 9367180 TI - Characterization of a strictly specific acid beta-galactosidase from Achatina achatina. AB - An acid beta-galactosidase was isolated from the digestive juice of Achatina achatina and purified to homogeneity by anion exchange, gel-filtration and hydroxyapatite chromatographies. This enzyme is soluble, as are the cytosolic beta-galactosidases, functions at acid pH like the lysosomal enzymes but differs from the other soluble animal beta-galactosidases in that it is highly specific for the beta-D-galactosyl residue. In addition, it cleaves the beta1-4 linkage much faster than the beta1-3 and beta1-6 linkages. The enzyme is a monomeric glycoprotein with a molecular mass of 120-125 kDa and the carbohydrate moiety makes up approximately 6% (w/w) of the protein. The amino acid composition displays an important amount of acidic/amide and hydroxy amino acid residues and a low content of basic residues. The enzyme activity is markedly affected by the ionic strength of the medium and the rate-pH curve was shifted towards higher pH values in the presence of added salt. Acid beta-galactosidase is capable of catalysing transgalactosylation reactions. The yields of galactosylation of hydroxy amino acid derivatives, catalysed by the enzyme in the presence of lactose as the glycosyl donor, were higher than those reported previously with conventional sources of beta-galactosidases. In addition, the pH optimum is different for the hydrolysis (pH 3.2) and transgalactosylation (pH 5.0) reactions. On the basis of this work, the enzyme could be used as a tool in the structural analysis of D-galactose-containing oligosaccharide chains, as well as for the synthesis of glycoconjugates. PMID- 9367181 TI - Prostasome to sperm transfer of CD13/aminopeptidase N (EC 3.4.11.2). AB - Prostasomes are membranous vesicles (150-200 nm in diameter) that are present in human semen. They are secreted by the prostate gland and contain large amounts of cholesterol, sphingomyelin and Ca2+. In addition, some of their proteins are enzymes. Prostasomes enhance the motility of ejaculated spermatozoa and are involved in a number of additional biological functions. In previous papers, we demonstrated that lipid can be transferred from prostasomes to sperm by a fusion process occurring at slightly acidic pH. CD (cluster antigens) are ubiquitous proteins; in this paper, we demonstrate that CD13/aminopeptidase N is present is semen, where it is bound to prostasomes. Upon mixing prostasomes and sperm at slightly acidic pH (7 or less), aminopeptidase is transferred from prostasomes to sperm. This evidence comes from enzymatic activity determinations and from the use of the monoclonal antibody, anti-human CD13. The transfer was about 8% of total prostasomal activity at pH 5 and with a prostasome to sperm ratio of 2 (on a protein basis). The transfer did not occur at pH 8.0, but was measurable at pH 7. Therefore, this mechanism may represent a means of modifying the composition and the biological properties of ejaculated sperm. PMID- 9367182 TI - Chemical characterization of pheomelanogenesis starting from dihydroxyphenylalanine or tyrosine and cysteine. Effects of tyrosinase and cysteine concentrations and reaction time. AB - Two types of melanin pigment are produced in mammals; the brown-to-black eumelanins and the yellow-to-reddish-brown pheomelanins. The switch from one type of melanin to the other appears to be regulated by the levels of tyrosinase and thiols, such as cysteine and glutathione. This study examines the process of pheomelanin formation starting from dihydroxyphenylalanine (dopa) or tyrosine and cysteine. We prepared pheomelanins by tyrosinase oxidation of dopa or tyrosine in the presence of cysteine. Experimental variables were reaction time, tyrosinase concentration, and dopa or tyrosine to cysteine ratio. Following the reactions, we measured concentrations of tyrosine, dopa, cysteine and cysteinyldopas, amounts of total melanin (TM) by Soluene-350 solubilization and aminohydroxyphenylalanine (AHP), a specific indicator of pheomelanin, formed by hydriodic acid hydrolysis, and absorbance ratio, A650/A500. It was found that (1) mixed melanogenesis is a heterogeneous process in which pheomelanogenesis proceeds first, followed by eumelanogenesis, as shown by changes in the tyrosine and cysteinyldopa concentrations, the AHP/TM ratio, and the A650/A500 ratio during the course of melanogenesis and (2) lower tyrosinase concentration favors pheomelanogenesis even when the availability of cysteine is limited, as shown by AHP/TM ratios that were higher than the corresponding tyrosine to cysteine ratios. These results indicate that the switch from eumelanogenesis to pheomelanogenesis can be achieved by lowering the tyrosinase activity, which conforms to our proposal that tyrosinase activity is the major factor controlling the course of melanogenesis. PMID- 9367183 TI - Administration of ATP-MgCl2 following hemorrhage and resuscitation increases hepatic phosphoenolpyruvate carboxykinase and decreases pyruvate kinase activities. AB - Since administration of ATP-MgCl2 following trauma and hemorrhagic shock improves tissue perfusion as well as cell and organ function, the aim of this study was to determine whether this agent has any salutary effects on the hepatic rate controlling enzymes specific for gluconeogenesis, such as phosphoenolpyruvate carboxykinase (PEPCK), and for glycolysis, such as pyruvate kinase (PK), under such conditions. To study this, rats underwent a 5-cm midline laparotomy (i.e., trauma-induced) and were bled to and maintained at a mean arterial pressure of 40 mm Hg until 40% of maximum bleed out volume was returned in the form of Ringer's lactate (RL). The animals were then resuscitated with 3 times the volume of shed blood with RL over 45 min, followed by 2 times RL with ATP-MgCl2 (50 micromol/kg body wt.) or an equivalent volume of normal saline over 95 min. Hepatic PEPCK, PK and glucokinase activities were determined 4 h after the completion of resuscitation. The mRNA levels of PEPCK and PK in the isolated hepatocytes were determined by Northern blot analysis. The results indicate that glucokinase activity was not significantly altered after hemorrhage, irrespective of ATP MgCl2 treatment. Although the mRNA levels of PEPCK were similar in all groups, PEPCK activity decreased significantly after hemorrhage. ATP-MgCl2 treatment, however, restored PEPCK activity. Hemorrhage resulted in an increase in PK activity and its mRNA. ATP-MgCl2 treatment significantly decreased PK activity and the mRNA. Thus, up-regulation of the gluconeogenic enzyme, PEPCK, and down regulation of the glycolytic enzyme, PK, by ATP-MgCl2 may be responsible, in part, for the beneficial effects of this agent following trauma-hemorrhage and resuscitation. PMID- 9367184 TI - Carbohydrate analysis of porcine thyroglobulin isoforms with different iodine contents. AB - To further validate the relationship between thyroid hormone formation and the carbohydrate structure of thyroglobulin (Tg), we reinvestigated the relationship between the iodine content and the asparagine-linked oligosaccharide structures of porcine Tg. Purified porcine Tg was further separated into isoforms (Tg-F1, F2 and -F3) with a DEAE-cellulose ion-exchange chromatography column. The iodine residues, neutral sugar and sialic acid were analyzed for the separated Tg isoforms and their asparagine-linked oligosaccharide structures were analyzed. The asparagine-linked oligosaccharides were released from Tg-F1, -F2 and -F3 by hydrazinolysis and each oligosaccharide was labeled with p-aminobenzoic acid octyl ester (ABOE). The ABOE-labeled oligosaccharides from Tg-F1, -F2 and -F3 were analyzed for their relative content in oligosaccharides of each structure type by chemical methods and DEAE- and ConA high-performance liquid chromatography (HPLC) columns. As a result, it was revealed that the Tg fraction eluted at higher ionic strength from a DEAE-cellulose column is apt to contain more of each iodoamino acid, as well as total content of iodine, larger negative zeta-potential, conforming to sialic acid content in the Tg molecule and to a higher content of di-sialo-bi-antennary complex and to high mannose type oligosaccharides. These results support the conclusion that iodine organification of the Tg molecule is correlated with asparagine-linked oligosaccharide completion. PMID- 9367185 TI - Cyanate causes depletion of ascorbate in organisms. AB - Ascorbate-dehydroascorbate redox cycle plays a key role in protecting organisms from an excess of oxidants. Recently, we found a novel reaction of dehydroascorbate with cyanate under the conditions of neutral pH and ordinary temperature. In this report, we demonstrated that through this irreversible reaction, cyanate causes the depletion of ascorbate in the matrix, where the ascorbate-dehydroascorbate redox cycle revolves. When the leaves of weed (Erigeron canadensis) were soaked in sodium cyanate solution generally used as a herbicide, the depletion of ascorbate as well as dehydroascorbate in them was observed, followed by the change in color from green to brown. These results suggest that a possible way of cyanate toxicity is to inflict oxidative stress on organisms. PMID- 9367186 TI - Carotenoids and protection of phospholipids in solution or in liposomes against oxidation by peroxyl radicals: relationship between carotenoid structure and protective ability. AB - The ability of carotenoids to protect egg-yolk phosphatidylcholine (EYPC) lipids against oxidation by peroxyl radicals generated from azo-initiators was studied. In homogeneous organic solution, all the carotenoids tested ameliorated lipid peroxidation by AMVN, but none was as effective as alpha-tocopherol. Beta-ring carotenoids showed a correlation between protective effect and rate of carotenoid destruction. Beta,beta-Carotene and zeaxanthin, which react with peroxyl radicals at similar rates, gave a similar degree of protection in organic solution. The reactivity and protective ability of the 4,4'-diketocarotenoids, astaxanthin and canthaxanthin was less. Carotenoids incorporated into ordered membrane systems (EYPC liposomes) displayed different protective efficacies. Zeaxanthin and beta cryptoxanthin were more effective than beta,beta-carotene against oxidation initiated in the aqueous and lipid phases. Astaxanthin and canthaxanthin afforded less protection to the liposomal lipids. Lycopene was destroyed most rapidly but was least effective as an antioxidant. Located in the hydrophobic inner core of the bilayer, the hydrocarbons lycopene and beta,beta-carotene would not be in a position to readily intercept free-radicals entering the membrane from the aqueous phase. Carotenoids with polar end groups span the bilayer with their end groups located near the hydrophobic-hydrophillic interface where free-radical attack from AAPH first occurs. Hydrogen abstraction from C-4 may be one of the mechanisms of carotenoid antioxidant activity in this system. The chemical reactivity of a carotenoid is not the only factor that determines its ability to protect membranes against oxidation. The position and orientation of the carotenoid in the bilayer is also of importance. PMID- 9367187 TI - Preparation and gas chromatographic-mass spectrometric analysis of N-acetyl-O trimethylsilyl derivatives of long-chain base residues of natural sphingomyelin. AB - A procedure for the preparation of long-chain base residues of egg yolk, bovine milk and bovine brain sphingomyelin was developed. The bases were converted to N acetyl-O-trimethylsilyl (TMS) derivatives before being submitted to gas chromatography and mass spectrometry. The chromatographic profile of the milk sample was complex with thirteen peaks, whereas the profiles of brain and egg yolk long-chain bases were simple and remarkably similar. PMID- 9367188 TI - Reversed-phase high-performance liquid chromatographic method for the determination of the 11-hydroxythromboxane B2 anomers equilibrium. AB - An improved reversed-phase HPLC method for the separation and detection of both hemiacetalic 11-hydroxy anomers of thromboxane B2 (TXB2) is described. Water acetonitrile mixtures have served as mobile phases. By diminishing stepwise the temperature of the chromatographic system from 40 to 0 degrees C, the UV absorbance profile of TXB2 changed from one broad peak to two clearly separated narrow peaks corresponding to the two anomers existing in equilibrium. Modification of the mobile phase pH from 1.6 to 6.9 (0 degrees C) resulted in different concentration ratios of the anomers. The equilibrium constant and the Gibbs free energy were calculated. The intermediate open aldehyde form of TXB2 is unstable and, therefore, cannot be observed either by HPLC or by 1H NMR measurements. PMID- 9367189 TI - Application of [(125)I]-[Tyr8]-substance P prepared by the chloramine-T method to receptor-binding experiments after subsequent reduction with mercaptoethanol and purification by reversed-phase liquid chromatography. AB - Radiolabeling of [Tyr8]-substance P ([Tyr8]-SP) with the (125)I-isotope was performed by use of the chloramine-T technique. The primary formed radiolabeled product, having been quantitatively converted to the corresponding sulfoxide yielding [(125)I]-[Tyr8]-(Met11-->O)-SP completely lacked any binding to proteins rich in SP receptor populations. However, after reductive treatment with mercaptoethanol for about 2 h, a complete reconstitution of the Met11 thioether structure was observed. The reduced peptide, consisting of [(125)I]-[Tyr8] (Met11)-SP was separated from its by-products by reversed-phase high-performance liquid chromatography on octadecylsilyl silica gel with 100 mM triethyl ammonium formate buffer containing 22% acetonitrile (pH 2.2). The labeled SP derivative prepared by this two-step synthesis was obtained in 73% overall yield related to the [Tyr8]-SP starting material and exhibited a specific activity of 1.9-10(6) Ci/M. In contrast to [(125)I]-[Tyr8]-->(Met11-->O)-SP, satisfactory receptor binding was now observed with the [(125)I]-->[Tyr8]-(Met11)-SP derivative. PMID- 9367190 TI - Alteration of redox state of human serum albumin in patients under anesthesia and invasive surgery. AB - Human serum albumin is a mixture of mercapt- (HMA, reduced form) and nonmercaptalbumin (HNA, oxidized form). We studied the mercapt<-->nonmercapt conversion of human serum albumin, which reflects the redox state of the extracellular fluids, in cardiac and other common surgical_ patients using high performance liquid chromatography. Mean values of [(HMA)/(HMA+HNA)]+/-standard deviation, fHMA+/-sigma], for patients who received common surgery (group 1) and cardiac surgery (group 2) at the start of anesthesia were 0.636+/-0.050 (n = 83) and 0.615+/-0.062 (n = 14), respectively. fHMA values were markedly lower than those for healthy male adults of 0.750+/-0.028 (n = 28). fHMA values increased at 24 h after the start of anesthesia and decreased on the 4th postoperative day in most of the patients. These postoperative changes were prominent in cardiac surgical patients. Although fHMA values after the 7th postoperative day recovered to those at the start of anesthesia in almost all of common surgical patients, those in cardiac surgical patients never recovered even on the 21st postoperative day. PMID- 9367191 TI - Use of immobilized metal ion affinity chromatography and dye-ligand chromatography for the separation and purification of rainbow trout pituitary gonadotropins, GTH I and GTH II. AB - A new procedure is described for the purification of gonadotropic hormones (GTHs) from the pituitary glands of vitellogenic rainbow trout. The procedure utilizes immobilized metal ion affinity chromatography (IMAC) on a column containing immobilized iminodiacetic acid (Toyopearl AF Chelate) charged with Cu2+ ions as a critical step for the efficient separation of GTH I and GTH II. Further purification of both GTH fractions on Cibacron Blue F3GA immobilized on Toyopearl was followed by HPLC size-exclusion for GTH II. The resulting electrophoretically homogeneous preparations possessed a characteristic range of biological activity in the stimulation of steroidogenesis in vitro. N-Terminal sequences of the GTH I and GTH II subunits purified using reversed-phase HPLC revealed a high level of homology with those of GTH subunits found in three other salmonid fish species. In contrast to salmon GTH II, two different alpha-subunits were observed in trout GTH II. The cross-reactivity between GTH I and GTH II was studied in radioimmunoassay using antibodies against Chinook salmon GTH II beta-subunit and rainbow trout GTH I dimer. PMID- 9367192 TI - Effect of different surfactants on the separation by micellar electrokinetic chromatography of a complex mixture of dipeptides in urine of prolidase-deficient patients. AB - Prolidase deficiency is a severe disorder characterized by massive excretion of metabolites with closely related structures. At present, micellar electrokinetic chromatography is the separation method which provides the highest selectivity of structurally similar solutes. However, the structure of a surfactant can greatly affect the selectivity of separation depending on factors such as the length of hydrophobic alkyl chain or the nature of the hydrophilic group. Here we investigated the effect of three non-ionic and four anionic detergents for obtaining the best separation conditions for resolving imidodipeptide mixtures. The effect on resolution of variables such as temperature, surfactant concentrations and organic solvents was also examined. The greatest resolution was obtained at the lowest temperature studied (10 degrees C) using 50 mM sodium borate, pH 9.3 containing 50 mM pentanesulfonate and 10% (v/v) methanol. Under these experimental conditions almost all excreted components were baseline separated and identified. PMID- 9367193 TI - Fractionation of RNA polymerase II transcription factors from HeLa cell nuclear extracts by affinity chromatography on "DNA-like" phosphorylated polystyrene. AB - It was previously shown that phosphorylated cross-linked polystyrene derivatives specifically interacted with anti-DNA antibodies and anti-phospholipid antibodies present in the sera of systemic lupus erythematosus patients. These resins are potential candidates as stationary phases in affinity chromatography. We wondered whether these biospecific resins might allow the fractionation of DNA binding proteins such as RNA polymerase II transcription factors from HeLa cell nuclear extracts. Indeed, these proteins play a major role in gene regulation in mammalian cells and their purification still requires numerous steps. To study the biospecificity of DNA-like phosphorylated polystyrene derivatives, ethanolamine sulfamide crosslinked polystyrene derivatives were phosphorylated at various rates and HeLa cell nuclear extracts were adsorbed on these resins. Adsorbed proteins were eluted with increasing concentrations of aqueous potassium chloride. Collected fractions were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and the biological activities of the eluted transcription factors were tested by in vitro transcription assay. Results showed that the elution of transcription factors depended on the substitution rate in phosphoester groups of the resins. It appears that specific interactions were developed between the polymers and the transcription factors. Moreover, the eluted transcription factors kept their biological activity. These results lead us to propose the purification of RNA polymerase II transcription factors using the phosphorylated polystyrene resins as stationary phases. PMID- 9367194 TI - High-performance liquid chromatographic separation and tandem mass spectrometric identification of breakdown products associated with the biological hydrolysis of a biomedical polyurethane. AB - As part of ongoing investigations into the biological degradation of biomaterials, methods have been developed to isolate and chemically analyze polymer biodegradation products. The use of these methods can provide information on the biodegradation product profiles and yield concentration levels for the isolated products. The latter information is required to assess the toxicological nature of biomaterials and their related degradation products. In this study a model biomedical polyurethane was synthesized with toluene diisocyanate, polyester diol and ethylene diamine, and then incubated at 37 degrees C in a biological solution containing enzyme. The biodegradation products were isolated from the in vitro system and prepared for HPLC analysis, by using a combination of ultrafiltration, freeze drying and liquid-solid extraction. The ultrafiltration and the liquid-solid extraction effectively removed protein contamination. The separation of more than 20 degradation products, with gradient HPLC, was optimized using a photodiode array detector. The separated degradation products were identified using a tandem mass spectrometer. The model polyurethane was labeled with 14C in different segments, in order to assist in confirming the efficiency of the sample preparation and isolation methods. A detection limit of 2 ng was found. No toluene diamine - a suspected human carcinogen associated with some medical implants - could be found in the test samples. This represents a significant finding since the amount of this injected sample actually contained a total of 28 microg of degradation products isolated from the incubation medium. PMID- 9367195 TI - Determination of the main hydrolysis products of organophosphorus nerve agents, methylphosphonic acids, in human serum by indirect photometric detection ion chromatography. AB - For the verification of the use of chemical warfare agents (CWA), sarin, soman and VX, a simple rapid and accurate method which allows us to simultaneously determine their degradation products, isopropyl methylphosphonic acid (IPMPA), pinacolyl methylphosphonic acid (PMPA), ethyl methylphosphonic acid (EMPA) and methylphosphonic acid (MPA), in human serum, was explored by indirect photometric detection ion chromatography (IPD-IC) which employs an anion-exchange column. IC analysis was performed after sample preparation with an Ag+-form cation-exchange resin cartridge, and the four methylphosphonic acids could be separated well. The proposed conditions are as follows: eluent, 0.5 mM phthalic acid-0.1 mM Tris (hydroxymethyl) aminomethane-5% acetonitrile; flow-rate, 1.0 ml/min; temperature, 50 degrees C; UV detector, 266 nm. All four methylphosphonic acids were eluted within 30 min with hardly any disturbance by impurities in the serum. Linear calibration curves were obtained for MPA, EMPA and IPMPA in the concentration range from 50 ng/ml to 1 microg/ml and for PMPA from 100 ng/ml to 1 microg/ml. The relative standard deviation for the methylphosphonic acids ranged from 3.8 to 6.9% at 500 ng/ml and the detection limits were 40 ng/ml for MPA, EMPA and IPMPA and 80 ng/ml for PMPA. The method would be suitable for analysis of human serum samples. PMID- 9367196 TI - Dye-incorporated poly(EGDMA-HEMA) microspheres as specific sorbents for aluminum removal. AB - Aluminum [Al(III)] adsorption onto dye-incorporated poly(ethylene glycol dimethacrylate-hydroxyethyl methacrylate) [poly(EGDMA-HEMA)] microspheres was investigated. Poly(EGDMA-HEMA) microspheres, in the size range of 150-200 microm, were produced by a modified suspension polymerization of EGDMA and HEMA. The reactive dyes (i.e., Congo Red, Cibacron Blue F3GA and Alkali Blue 6B) were covalently incorporated to the microspheres. The maximum dye load was 14.5 micromol Congo Red/g, 16.5 micromol Cibacron Blue F3GA/g and 23.7 micromol Alkali Blue 6B/g polymer. The maximum Al(III) adsorption on the dye microspheres from aqueous solutions containing different amounts of Al(III) ions were 27.9 mg/g, 17.3 mg/g and 12.2 mg/g polymer for the Congo Red, Cibacron Blue F3GA and Alkali Blue 6B, respectively. The maximum Al(III) adsorption was observed at pH 7.0 in all cases. Non-specific Al(III) adsorption was about 0.84 mg/g polymer under the same conditions. High desorption ratios (95%) were achieved in all cases by using 0.1 M HNO3. It was possible to reuse these dye-incorporated poly(EGDMA-HEMA) microspheres without significant losses in the Al(III) adsorption capacities. PMID- 9367197 TI - Simple and rapid determination of enflurane in human tissues using gas chromatography and gas chromatography-mass spectrometry. AB - A simple, rapid and reliable method was devised to determine the levels of enflurane in human tissues, using gas chromatography and gas chromatography-mass spectrometry. 1,4-Dioxane was used as an internal standard (I.S.). Enflurane and the I.S. were extracted from 0.25 g of body tissues using an automatic headspace sampler and 1 ml of headspace gas was injected into the gas chromatograph. Enflurane was analyzed qualitatively by gas chromatography-mass spectrometry and quantitatively by gas chromatography with a flame-ionization detector. The calibration curves in all tissues examined were linear in the concentration range 1-100 microg/0.25 g. The lower limit of detection was 200-300 ng/0.25 g. The accuracy and precision of this method were evaluated at two different concentrations, 1 and 20 microg/0.25 g. The coefficient of variation ranged from 3.4-13.4%. We used this method to determine the presence of enflurane in tissues from an autopsied individual who died suddenly during extirpation of a malignant tumor. PMID- 9367198 TI - Determination of p-trifluoromethylphenol, a metabolite of fluoxetine, in tissues and body fluids using an electron-capture gas chromatographic procedure. AB - An electron-capture gas chromatographic procedure was developed for the analysis of p-trifluoromethylphenol, an O-dealkylated metabolite of fluoxetine, in biological samples. A basic extraction of the biological sample was employed, followed by derivatization with pentafluorobenzenesulfonyl chloride. The internal standard, 2,4-dichlorophenol, was added to all samples used in the procedure to aid in quantitation. The practical limit of detection (signal-to-noise ratio>3) for p-trifluoromethylphenol was <5 ng/ml in human plasma samples, <10 ng/g of rat brain tissue, <25 ng/g of rat liver tissue and <25 ng/ml in human and rat urine samples. In the rat, the levels of free p-trifluoromethylphenol in the liver were 10-fold higher than those in the brain, and a substantial amount was excreted in the urine. Human urine samples contained levels of free p-trifluoromethylphenol approximately 30-fold higher than those found in human plasma samples. The procedure described is useful for the detection and quantitation of free p trifluoromethylphenol in humans and rats treated with fluoxetine. PMID- 9367199 TI - Determination of N,N',N"-triethylenthiophosphoramide in biological samples using capillary gas chromatography. AB - A sensitive assay for the determination of N,N',N"-triethylenthiophosphoramide (thioTEPA) in microvolumes of human plasma and urine has been developed. ThioTEPA was analysed using gas chromatography with selective nitrogen-phosphorus detection, after extraction with ethyl acetate from the biological matrix. Diphenylamine is the internal standard. The limit of quantitation was 0.1 ng/ml, using only 100 microl of sample; recoveries ranged between 85 and 100% and both accuracy and precision were less than 10%. Using a flame ionisation nitrogen phosphorus detector, the assay was not linear over the concentration range of 2 1000 ng/ml for plasma and 10-1000 ng/ml for urine. Linearity was accomplished in the range of 1-1000 ng/ml for plasma and urine when a thermionic nitrogen/phosphorous detector was used. The stability of thioTEPA in plasma proved to be satisfactory over a period of 3 months, when kept at -20 degrees C, whereas it was stable in urine for at least 1 month at -80 degrees C. ThioTEPA plasma concentrations of two patients treated with thioTEPA are presented demonstrating the applicability of the assay. PMID- 9367200 TI - Quantitative determination of BMS-186716, a thiol compound, in rat plasma by high performance liquid chromatography-positive ion electrospray mass spectrometry after hydrolysis of the methyl acrylate adduct by the native esterases. AB - During method development in support of non-clinical studies in animal models, BMS-186716 was found to be extremely unstable in blood and plasma. Stabilization of the compound was achieved by reacting the compound with methyl acrylate (MA) in blood, from which the plasma was then prepared. While the resulting BMS-186716 MA adduct was found to be stable in dog plasma, and hence it was used as the basis for the method developed for analysis of dog plasma samples, the BMS-186716 MA adduct was found to be unstable in rat plasma as it was readily hydrolyzed to BMS-186716-acrylic acid (AA) by native esterases found in rat plasma. Although the finding of the instability of BMS-186716-MA in rat plasma was not the result of prospective planning, we were able to successfully develop a quantitative bioanalytical method using BMS-186716-AA as the analyte instead of the originally planned BMS-186716-MA analyte. The standard and quality-control (QC) samples were prepared by spiking blank plasma with BMS-186716-MA, and then allowing them to stand at room temperature for 1 h to convert BMS-186716-MA to BMS-186716-AA. After adding the internal standard BMS-188035-AA, each sample was acidified with HCl and then extracted with methyl tert.-butyl ether. The reconstituted extract was injected into a HPLC-electrospray ionization mass spectrometric system for detection by positive ion electrospray ionization. A lower limit of quantitation (LLQ) of 5 ng/ml was achieved, using 0.1 ml plasma and a standard curve range of 5-5000 ng/ml. PMID- 9367201 TI - Buspirone metabolite structure profile using a standard liquid chromatographic mass spectrometric protocol. AB - A rapid and systematic LC-MS protocol is utilized to profile buspirone metabolites. Analysis of rat bile, urine and liver S9 samples using a standard LC MS method provides structural information for 25 metabolites. The resulting buspirone metabolite structure database contains characteristic retention time, molecular mass and MS-MS product ion information for each compound. Metabolites are categorized according to profile groups, which illustrate that substitution reactions are primarily associated with the azaspirone decane dione and pyrimidine substructures. Structures of new buspirone metabolites are reported and include the despyrimidinyl, despyrimidinylpiperazine, glucuronide, hydroxyglucuronide (four isomers), methoxyglucuronide and hydroxymethoxyglucuronide (two isomers) buspirone metabolites. PMID- 9367202 TI - Highly sensitive high-performance liquid chromatographic-tandem mass spectrometric method for the analysis of dextromethorphan in human plasma. AB - A stable-isotope-dilution HPLC-tandem mass spectrometry-based method was developed for the determination of dextromethorphan in human plasma. Plasma samples were prepared for analysis by solid-phase extraction on octadecylsilane extraction cartridges. Dextromethorphan and the deuterium-labeled dextromethorphan internal standard were chromatographed on a short reversed-phase column and detected by a selected-reaction-monitoring scheme. Linear standard curves were obtained over three orders of magnitude and the limit of quantitation for dextromethorphan was 50 pg/ml, using a 1-ml plasma sample. The combination of HPLC and electrospray tandem mass spectrometry resulted in a rapid, selective and sensitive method for the analysis of dextromethorphan in plasma. The method was applied for the evaluation of the pharmacokinetic profile of dextromethorphan in human volunteers following peroral administration. PMID- 9367203 TI - Determination of cloxacillin in milk and blood of dairy cows by high-performance liquid chromatography. AB - A rapid and sensitive high-performance liquid chromatographic method is described for the determination of cloxacillin residues in milk and serum. Only a clean-up step after deproteinization is necessary before the analysis. The chromatographic system involves the use of a C18 column and ultraviolet absorbance detection at 225 nm. The mobile phase was acetonitrile-0.02 M KH2PO4 (21:79) at pH 5. Recoveries for cloxacillin were 83.5 and 75.7% in serum and milk, respectively. Detection limits (10 ng/ml in milk and 50 ng/ml in serum) were below the stipulated European Union maximum residue limits for cloxacillin. Thus, the described method showed the same accuracy, precision and sensitivity as the microbiological assays but without interferences caused by other drugs commonly used in therapy. Analysis of different blood and milk samples obtained at different times from dairy cows treated with an intramammary dose of cloxacillin benzatine showed undetectable cloxacillin levels both in milk and blood samples. PMID- 9367204 TI - Automated determination of tramadol enantiomers in human plasma using solid-phase extraction in combination with chiral liquid chromatography. AB - A sensitive and automated method for the separation and individual determination of tramadol enantiomers in plasma has been developed using solid-phase extraction (SPE) on disposable extraction cartridges (DECs) in combination with chiral liquid chromatography (LC). The SPE operations were performed automatically by means of a sample processor equipped with a robotic arm (ASPEC system). The DEC filled with ethyl silica (50 mg) was first conditioned with methanol and phosphate buffer, pH 7.4. A 1.0-ml volume of plasma was then applied on the DEC. The washing step was performed with the same buffer. The analytes were eluted with 0.15 ml of methanol, and 0.35 ml of phosphate buffer, pH 6.0, containing sodium perchlorate (0.2 M) were added to the extract before injection into the LC system. The enantiomeric separation of tramadol was achieved using a Chiralcel OD R column containing cellulose tris-(3,5-dimethylphenylcarbamate) as chiral stationary phase. The mobile phase was a mixture of phosphate buffer, pH 6.0, containing sodium perchlorate (0.2 M) and acetonitrile (75:25). The mobile-phase pH and the NaClO4 concentration were optimized with respect to enantiomeric resolution. The method developed was validated. Recoveries for both enantiomers of tramadol were about 100%. The method was found to be linear in the 2.5-150 ng/ml concentration range [r2=0.999 for (+)- and (-)-tramadol]. The repeatability and intermediate precision at a concentration of 50 ng/ml were 6.5 and 8.7% for (+)-tramadol and 6.1 and 7.6% for (-)-tramadol, respectively. PMID- 9367205 TI - High-performance liquid chromatographic assay for CI-1004, a dual-inhibitor antiinflammatory agent, in rat, rabbit, dog, monkey and human plasma. AB - CI-1004 and PD 138389 (internal standard, I.S.), were isolated from rat, rabbit, dog, monkey and human plasma by solid-phase extraction with Bond-Elut C18 cartridges. Liquid chromatographic separation was achieved isocratically on a Zorbax Rx-C8 analytical column (250 mm x 4.6 mm I.D). The mobile phase consisted of acetonitrile-20 mM ammonium acetate (65:35, v/v), (pH 4.0). Column temperature was either 40 degrees C (human assay) or 45 degrees C and column effluent was monitored spectrophotometrically at 360 nm. Specificity, chromatographic performance parameters, system repeatability, recovery from matrix, linearity, precision, accuracy and stability were evaluated. Mean retention times (+/-S.D.) of CI-1004 and I.S. were 7.8+/-0.1 and 10.9+/-0.2 at 40 degrees C and 7.7+/-0.2 min and 10.7+/-0.2 min at 45 degrees C. No interfering peaks were observed at the retention time of CI-1004 throughout the validation process. Peak height ratios were proportional to CI-1004 over the concentration range of 7.5-5000 ng/ml in rat, rabbit and monkey plasma and 2.5-5000 ng/ml in dog and human plasma. Recovery of low, medium and high standards of CI-1004 ranged from 82.8-107% from all animal species and recovery of I.S. from rat, rabbit, dog and monkey plasma ranged from 77.5-82.0% and from human plasma was 111%. Assay precision for CI 1004 based on quality control samples was less than or equal to 8.5% C.V. with an accuracy (percentage relative error) of +/-4.7% for all species. Minimum quantitation limit of CI-1004 was 7.5 ng/ml for 0.2 ml rat, rabbit and monkey plasma samples and 2.5 ng/ml for 0.5 ml dog and human plasma samples. The method is suitable for studying the preclinical and clinical pharmacokinetics of CI 1004. PMID- 9367206 TI - Enantioselective high-performance liquid chromatographic determination of nicardipine in human plasma. AB - A sensitive method for the enantioselective high-performance liquid chromatography (HPLC) determination of nicardipine in human plasma is described. (+)-Nicardipine, (-)-nicardipine and (+)-barnidipine as an internal standard are detected by an ultraviolet detector at 254 nm. Racemic nicardipine in human plasma was extracted by a rapid and simple procedure based on C18 bonded-phase extraction. The extraction samples were purified and concentrated on a pre-column using a C1 stationary phase and the enantiomers of nicardipine are quantitatively separated by HPLC on a Sumichiral OA-4500 column, containing a chemically modified Pirkle-type stationary phase. Determination of (+)- and (-)-nicardipine was possible in a concentration range of 5-100 ng ml(-1) and the limit of detection in plasma was 2.5 ng ml(-1). The recoveries of (+)- and (-)-nicardipine added to plasma were 91.4-98.4% and 93.3-96.7%, respectively, with coefficients of variation of less than 9.0 and 9.4% respectively. The method was applied to low level monitoring of (+)- and (-)-nicardipine in plasma from healthy volunteers. PMID- 9367207 TI - Simultaneous determination of atenolol and chlorthalidone in plasma by high performance liquid chromatography. Application to pharmacokinetic studies in man. AB - An HPLC method developed to detect in a single run both atenolol and chlorthalidone, extracted from plasma, using two detectors (UV for chlorthalidone and fluorometric for atenolol) connected in series, is described. The drugs were separated on an ODS column at room temperature using a 0.05 M sodium dodecyl sulphate in phosphate buffer (pH 5.8)-n-propanol (95:5, v/v) solution, delivered at a flow-rate of 1.3 ml/min. Having ascertained the sensitivity (10 ng/ml of both drugs) and the intra-day reproducibility (pre-study validation), the reliability of the method was verified by inter-day assays (within-study validation) carried out during the analysis of plasma samples collected from healthy volunteers after single-dose treatment with atenolol+chlorthalidone tablets (pharmaceutical preparations containing 100+25 mg and 50+12.5 mg of the two drugs, respectively). PMID- 9367208 TI - Isolation of N,N-dialkylated derivatives of valproylglycinamide from dog plasma by active charcoal adsorption and their quantification by high-performance liquid chromatography. AB - A selective assay for quantification of N,N-dimethylvalproylglycinamide (DM-VGD) and N,N-diethylvalproylglycinamide (DE-VGD) in dog plasma utilizing reversed phase high-performance liquid chromatography and UV detection has been developed. These compounds are derivatives of the potential anticonvulsant drug, valproylglycinamide, which is currently undergoing clinical trials. The method is based on extraction of dog plasma with activated charcoal, separation of the charcoal pellet and extracting it with methanol, evaporation of the solvent and injecting the reconstituted residue onto the column. The active charcoal adsorption method is reliable and reproducible, and it provides a chromatogram free of interfering endogenous plasma compounds. The assay was validated and provided a limit of quantification of 2.3 mmol/l for DE-VGD and 5.3 mmol/l for DM VGD. Mean recovery of these compounds from plasma averages 75%. This analytical method is suitable for the quantitative determination of DM-VGD and DE-VGD in plasma and it has been applied to a pharmacokinetic study of these compounds in a dog. PMID- 9367209 TI - Automated determination of levodopa and carbidopa in plasma by high-performance liquid chromatography-electrochemical detection using an on-line flow injection analysis sample pretreatment unit. AB - An automated analytical procedure is described for the parallel determination of L-3,4-dihydroxyphenylalanine (levodopa, L-dopa, LD) and the analogous hydrazine compound carbidopa (CD) in dog plasma by ion-pair high-performance liquid chromatography with electrochemical detection (HPLC-ED). After deproteinization of the plasma samples with perchloric acid the catecholamines were extracted from the supernatant by adsorption on a small column filled with alumina. The extraction and redissolution were automatically performed in a flow injection analysis unit (FIA) coupled to the HPLC system. The performance of the whole system was tested on dog plasma samples including specimens taken after oral administration of the anti-Parkinsonism drug Duellin, which is a combination tablet of levodopa and carbidopa. PMID- 9367210 TI - Simplified high-performance liquid chromatographic method for determination of risperidone and 9-hydroxyrisperidone in serum from patients comedicated with other psychotropic drugs. AB - A HPLC method was developed for determination of risperidone and its therapeutically active main metabolite 9-hydroxyrisperidone in serum. After a single-step liquid-liquid extraction the analytes were separated on a C18 column and measured by UV detection at 280 nm. Inter-day coefficient of variation was <7% for both compounds at serum levels occurring in patients treated with ordinary doses. Studies of analytical interference showed that the most commonly coadministered antidepressants and benzodiazepines did not interfere. Some conventional low dose neuroleptics and clozapine did interfere, but this is of minor importance, because risperidone is intended as an alternative to these drugs. PMID- 9367211 TI - Simultaneous determination of pyrimethamine and sulphadoxine in human plasma by high-performance liquid chromatography after automated liquid-solid extraction. AB - A high-performance liquid chromatographic method with ultraviolet detection is described for the simultaneous measurement of pyrimethamine and sulphadoxine in human plasma. After an automated liquid-solid extraction on a C8 cartridge, the compounds are separated on a C18 column by isocratic elution; the mobile phase is methanol-acetonitrile-water (10:25:65, v/v/v) with triethylamine (1%) and adjusted to pH 5.6 with phosphoric acid. The eluent is monitored with an ultraviolet detector at 240 nm. The limit of quantification was 10 ng/ml for pyrimethamine and 22 microg/ml for sulphadoxine. No chromatographic interferences can be detected from endogenous compounds, other anti-malarial drugs or major drugs used for the treatment of children. Sulphadimethoxine is used as an internal standard. The method is accurate and precision is good with relative standard deviations lower than 6%. The chromatographic procedure takes 11 min. The method is comparatively rapid, simple, sensitive and can be used for therapeutic drug monitoring, clinical and pharmacokinetic studies. PMID- 9367212 TI - Prevalidation statistical design to assess analytical methods. Example of a quick liquid chromatographic assay of itraconazole in serum. AB - (A) An analysis-of-variance spreadsheet program is presented which allows to readily test and/or quantitate in a single run analytical linearity, matrix effect on recovery, repeatability of measurement and of extraction and the ruggedness of these features for up to three sessions. Owing to napierian logarithmic transformation, ANOVA mean squares directly read as relative standard deviations and checking linearity is straightforward. (B) A quick assay for therapeutic drug monitoring of itraconazole and its main metabolite was devised with the help of the program, and subsequently validated according to current quality control recommendations. The assay involves acetonitrile demixing extraction, reversed-phase HPLC and UV detection and shows acceptable performance from 0.06 to 5.0 mg/l (limit of detection about 0.03 mg/l). The prevalidation design fairly predicted precision and accuracy, was more informative about matrix effect and was even more demanding about analytical linearity. PMID- 9367213 TI - Determination of saquinavir in human plasma, saliva, and cerebrospinal fluid by ion-pair high-performance liquid chromatography with ultraviolet detection. AB - A high-performance liquid chromatographic method for the determination of the HIV protease inhibitor saquinavir in human plasma, saliva, and cerebrospinal fluid is described. Saquinavir was extracted from samples using C2 extraction columns prior to ion-pair, reversed-phase high-performance liquid chromatography with ultraviolet detection at 239 nm. The method has been validated over the range of 2.5-4000 ng/ml using a 0.6-ml sample volume. This assay has been used for the analysis of saquinavir in plasma and saliva of HIV-1-infected patients. PMID- 9367214 TI - Rapid and simple method to determine chloroquine and its desethylated metabolites in human microsomes by high-performance liquid chromatography with fluorescence detection. AB - A sensitive and selective method was developed for the simultaneous determination of chloroquine (CQ) and its desethylated metabolites monodesethylchloroquine (DCQ) and bisdesethylchloroquine (BDCQ) in human liver microsomes. Analytes were separated on a C1 column using methanol-water (70:30, v/v) and triethylamine (0.1% v/v) as the mobile phase. The fluorescence detector was set at 250 (excitation) and 380 nm (emission). Following protein precipitation with ice-cold acetonitrile, microsomal incubation supernatants were directly injected into the HPLC system. Typically, 200 microl of incubate were diluted with 200 microl of acetonitrile and 15 microl were injected. The limit of quantitation was 78 nM of CQ or metabolite. Intra-day variability averaged 2.9% for CQ, 1.5% for DCQ and 2.5% for BDCQ. Inter-day variability was 3.1% for CQ, 3.5% for DCQ and 3.7% for BDCQ. Mean accuracies were 100% for CQ and BDCQ and 102% for DCQ. PMID- 9367215 TI - High-performance liquid chromatographic determination of oxolinic acid in the plasma of seabass (Dicentrarchus labrax) anaesthetized with 2-phenoxyethanol. AB - A high-performance liquid chromatographic (HPLC) method for the determination of oxolinic acid (OA) in the plasma of seabass (Dicentrarchus labrax) anaesthetized with 2-phenoxyethanol is described. The samples were extracted and cleaned up by a solid-phase extraction procedure using C18 extraction cartridges. After the eluent was evaporated, the dry residue was dissolved in 1/15 M phosphate buffer. OA was determined by using an isocratic HPLC method with UV detection at 340 nm. Seabass drug-free plasma samples were spiked with OA at 0.2, 1.0, 5.0 and 25.0 microg/ml. Validation of the method showed good precision and accuracy. The mean recovery was 92.2%, with a relative standard deviation lower than 5%. The quantification limit was 0.2 microg/ml. The method was tested on 300 plasma samples of OA-treated seabass. PMID- 9367216 TI - Sensitive and convenient high-performance liquid chromatographic method for the determination of mitomycin C in human plasma. AB - An improved high-performance liquid chromatographic assay for the cytostatic drug mitomycin C in plasma is presented. The principal steps are precipitation of plasma proteins with acetonitrile, lyophilization of the supernatant and reversed phase chromatography on a Hypersil ODS 5 microm column with 0.01 M NaH2PO4 buffer (pH 6.5)-methanol (70:30, v/v) in isocratic mode. At a flow-rate of 1.3 ml/min a column pressure of 180-220 bar resulted. Porfiromycin served as internal standard. UV detection was performed at 365 nm. Quantitation limit based on a coefficient of variation <10% in intra- and inter-day assay was 5 microg/l mitomycin C, detection limit based on a signal-to-noise ratio of 3 was 1 microg/l. Recovery was 100% and linearity was shown for the whole range of concentration (1-500 microg/l). None of the five drugs used during chemoembolisation interfered with the assay in vitro. The assay meets the requirements for pharmacokinetic studies of mitomycin C in patients as regards sensitivity and ease of use. PMID- 9367217 TI - Solid-phase extraction and high-performance liquid chromatographic determination of tamoxifen and its major metabolites in breast tumour tissues. AB - A sensitive (200 ng/g) and selective reversed-phase high-performance liquid chromatography separation has been developed to determine the levels of tamoxifen, 4-hydroxytamoxifen (4-OH) and desmethyltamoxifen (DMT) in tumour tissue taken from patients undergoing tamoxifen therapy. A muBondapak C18 10 microm column (30 cm x 3.8 mm I.D.) was used, with a mobile phase of methanol-1% triethylamine at pH 9 (89:11, v/v). Sample preparation was carried out using a C2 (500 mg sorbent, 3 ml reservoirs) solid-phase extraction method, and extraction efficiencies were followed in individual extracts using a [3H]TAM radiolabelled spike (10000 dpm), with a range of 60-90%. Accuracy and precision (standard deviation) as determined from tumour spiked with radioinert tamoxifen and its metabolites ranged from 83.4-92.3% (+/-23-33%) at 20 microg/g; 85.2-87.7% (+/-18 23%) at 2 microg/g; 88-101% (+/-15-50%) at 0.2 microg/g and 63-94% (+/-13-24%) at 0.02 microg/g. Results from seventy-two patients show mean values (+/-S.D.) of 174+/-203 ng/g for 4-OH; 783+/-1326 ng/g for DMT and 410+/-458 ng/g for TAM, variations reflecting heterogeneity in levels between patients. This methodology can be routinely applied to the determination of tamoxifen and its metabolites in tumour tissues from patients undergoing tamoxifen therapy. PMID- 9367218 TI - Determination of irinotecan (CPT-11) and its active metabolite SN-38 in human plasma by reversed-phase high-performance liquid chromatography with fluorescence detection. AB - Sensitive high-performance liquid chromatographic assays have been developed to determine the levels of the lactone and lactone plus carboxylate (total) forms of the antitumor agent irinotecan (CPT-11) and its active metabolite SN-38, in human plasma. The related compound camptothecin was used as the internal standard. The selective sample pretreatment for the lactone forms involved a single solvent extraction with acetonitrile-n-butyl chloride (1:4, v/v), whereas the sample clean-up for the total forms was a simple protein precipitation with aqueous perchloric acid-methanol (1:1, v/v), which results in the conversion of the carboxylate to the lactone forms. Chromatography was carried out on a Hypersil ODS column, with detection performed fluorimetrically. The methods have been validated, and stability tests under various conditions have been performed. The lower limits of quantitation are 0.5 and 2.0 ng/ml for the lactone and total forms, respectively. The assays have been used in a single pharmacokinetic experiment in a patient to investigate the applicability of the method in vivo. PMID- 9367220 TI - Simultaneous determination of mycophenolic acid and its glucuronide conjugate in human plasma by a single-run ion-paring method. AB - A quick and robust HPLC method for simultaneous determination of plasma concentrations of mycophenolic acid (MPA) and its glucuronide conjugate (MPAG) is described. Using tetrabutylammonium dihydrogen phosphate as ion-paring reagent in the mobile phase, concentrations for both MPA and MPAG can be determined in a single HPLC run on a reversed-phase C18 column at 254 nm. The method is reproducible and accurate, with lower limits of quantification of 0.100 microg/ml for MPA and 0.800 microg/ml for MPAG. The quantification ranges of the method are 0.100-40.0 microg/ml for MPA and 0.800-400 microg/ml for MPAG using a 0.5-ml aliquot in the analysis. PMID- 9367219 TI - Determination of idarubicin and idarubicinol in plasma by capillary electrophoresis. AB - A rapid and sensitive capillary electrophoretic method for the determination of idarubicin and its metabolite idarubicinol in plasma has been developed and validated. Plasma is extracted by liquid-liquid extraction using chloroform. Idarubicin, idarubicinol and the internal standard daunorubicin can be separated in less than 5 min using a phosphate buffer of pH 5 with 70% acetonitrile. Laser induced fluorescence detection with an Ar ion laser operated at 488 nm provides a sensitive and selective detection method without interferences from biological fluids. The small sample volume of 100 microl is of particular advantage for studies in pediatric oncology. The reproducibility of the method has been shown to be sufficient for drug monitoring or pharmacokinetic studies. The limit of quantification for idarubicin in plasma is 0.5 ng/ml. PMID- 9367221 TI - Simultaneous determination of urinary cystathionine, lanthionine, S-(2 aminoethyl)-L-cysteine and their cyclic compounds using liquid chromatography mass spectrometry with atmospheric pressure chemical ionization. AB - A measurement system for cystathionine (Cysta) lanthionine (LT), and S-(2 aminoethyl)-L-cysteine (AEC), and reduced products of their ketimines, perhydro 1,4-thiazepine-3,5-dicarboxylic acid (PHTZDC), 1,4-thiomorpholine-3,5 dicarboxylic acid (TMDA) and 1,4-thiomorpholine-3-carboxylic acid (TMA) in the urine samples of a patient with cystathioninuria and normal human subjects has been developed, using column liquid chromatography-mass spectrometry. The recoveries were about 90-105% for Cysta, LT and AEC, and about 77-87% for PHTZDC, TMDA and TMA after ion-exchange treatment. The concentrations of Cysta and PHTZDC in the urine of a patient with cystathioninuria were much higher compared with those in the urine of normal human subjects. The concentrations of AEC and TMDA were almost the same. LT and TMA could not be detected in the urine samples by this method. This method proved useful for the determination of sulfur-containing amino acids and their cyclic compounds in biological samples. PMID- 9367222 TI - Determination of purine nucleoside phosphorylase activity in human erythrocytes by capillary electrophoresis. AB - Purine nucleoside phosphorylase (EC 2.4.2.1) activity in human erythrocytes was measured using capillary electrophoresis. Enzyme samples were directly loaded into the capillary without preconcentration or purification. The electrophoretic separations were carried out in an uncoated fused-silica capillary (75 microm internal diameter, effective length of 45 cm, total 72 cm) at an electric field of 415 V/cm at ambient temperature (25 degrees C). UV detection at 200 nm was used. Borate buffer (100 mmol/l, pH 9.5) was used as background electrolyte. The results obtained by CE compared favourably (r=0.989) with those of standard HPLC methods. The method presented is reliable, slightly faster and less expensive than the routinely performed HPLC method. PMID- 9367223 TI - Sensitive high-performance liquid chromatographic assay method for the determination of picroside I in plasma. AB - Picroliv is a new hepatoprotective agent, being developed at the Central Drug Research Institute (CDRI, Lucknow, India). Picroside I is a major active constituent of picroliv. A sensitive high-performance liquid chromatographic assay method in plasma has been developed and validated for the determination of picroside I in plasma. The method consists of extraction of the drug, after protein precipitation with methanol, from rabbit plasma samples. Separation was achieved using a C18 endcapped reversed-phase column coupled with a photodiode array detector and acetonitrile-0.1 M acetic acid (25:75) as mobile phase. The lower limit of quantification in plasma is 50 ng/ml. The standard curve was linear over the range of 50-500 ng/ml in rabbit plasma. The analytical recovery of picroside I added to plasma was >80%. The reproducibility was determined by the inter- and intra-assay precision which were <15%. PMID- 9367224 TI - Hearing loss in the RBF/DnJ mouse, a proposed animal model of Usher syndrome type IIa. AB - The Usher syndromes (US) are a group of inherited disorders that feature autosomal recessive neurosensory hearing loss or deafness with retinitis pigmentosa (RP). Moderate to severe non-progressive high frequency hearing loss with RP and normal vestibular function describes Usher syndrome type IIa, which has been localized to 1q41. Severe retinal degeneration in the inbred mouse strain RBF/DnJ is caused by rd3, a recessive gene located on mouse chromosome 1 distal to akp1 in a region which is orthologous to human 1q32-q42. We evaluated rd3 as a candidate for orthology with USH2A by first reducing and refining the relatively broad region in which rd3 is thought to reside. DNA of offspring from an RBF/DnJ x MOLF/Ei backcross was genotyped with PCR markers closely flanking the predicted location of rd3. Our haplotype analysis re-positioned rd3 to a 3.6 cM region between markers D1Mit273 (cen) and D1Mit209 (tel), consistent with the expected position of an USH2A murine orthologue. Consequently, rd3 is a positional candidate for Usher type IIa. Next we assessed the rd3/rd3 audiological phenotype to see how closely it paralleled that of Usher IIa. Audiological evaluation of mice at various ages revealed evidence of high frequency progressive hearing loss, previously unreported in the RBF/DnJ strain. However, this newly discovered hearing deficit was observed to be inherited independently of rd3, establishing that a completely different gene is responsible. PMID- 9367225 TI - Chronic strychnine administration into the cochlea potentiates permanent threshold shift following noise exposure. AB - To investigate whether elimination of the medial efferent system influences permanent threshold shift following noise exposure, we developed an animal model in which strychnine was chronically delivered into the cochlea via an osmotic pump. Pigmented female guinea pigs were allocated into three groups: group I was treated with strychnine (50 microM, 0.5 microl/h, 14 days) in the left ear and exposed to noise (105 dB SPL broadband, 3 h) 3 weeks after the cessation of the strychnine perfusion; group II received strychnine in the left ear but no noise exposure; group III was treated with Ringer's solution in the left ear and exposed to noise. Animals in group II developed no hearing loss after the strychnine perfusion. The operated ears in group I demonstrated greatest hearing threshold shift 3 h after noise exposure. Hearing recovered during 2 weeks after noise exposure in both operated and non-operated ears in groups I and III. Two weeks after noise exposure, the operated ears in group I showed significantly greater threshold shift at 12, 16, and 20 kHz compared to the operated ears in group III and non-operated ears in groups I and III. These findings suggest that chronic strychnine administration into the cochlea inactivates the medial efferents without changing hearing threshold and that the medial efferents help to protect against permanent threshold shift following noise exposure. PMID- 9367226 TI - A role for chloride in the suppressive effect of acetylcholine on afferent vestibular activity. AB - Afferents of the frog semicircular canal (SCC) respond to acetylcholine (ACh) application (0.3-1.0 mM) with a facilitation of their activity while frog saccular afferents respond with suppression (Guth et al., 1994). All recordings are of resting (i.e., non-stimulated) multiunit activity as previously reported (Guth et al., 1994). Substitution of 80% of external chloride (Cl-) by large, poorly permeant anions of different structures (isethionate, methanesulfonate, methylsulfate, and gluconate) reduced the suppressive effect of ACh in the frog saccular afferents. This substitution did not affect the facilitatory response of SCC afferents to ACh. Chloride channel blockers were also used to test further whether Cl- is involved in the ACh suppressive effect. These included: niflumic and flufenamic acids, picrotoxin, 5-nitro-2-(-3-phenylpropylamino)benzoic acid (NPPB), and 4,4'-dinitrostilbene-2,2'-disulfonic acid (DNDS). As with the Cl- substitutions, all of these agents reduced the suppressive response to ACh in the saccule, but not the facilitatory response seen in the SCC. The suppressive effect of ACh on saccular afferents is considered to be due to activation of a nicotinic-like receptor (Guth et al., 1994; Guth and Norris, 1996). Taking into account the effects of both Cl- substitutions and Cl- channel blockers, we conclude that changes in Cl- availability influence the suppressive effect of ACh and that therefore Cl- may be involved in this effect. PMID- 9367227 TI - Endothelin-1 causes luminal constrictions in rat cochlear veins. AB - Serum levels of the vasoconstrictor endothelin-1 (ET-1) increase in ischemia and systemic hypertension. We examined the effects of ET-1 on the cochlear microvasculature. Blood vessels were cast with methacrylate in adult male Wistar Kyoto rats, 10 min after intravenous injection of ET-1 (1.0 microg/kg); control animals received saline. Systemic blood pressure was recorded continuously. ET-1 increased the average systolic pressure by 18% and average diastolic pressure by 22% (P < 0.01). Scanning electron microscopy of cast vessels showed multiple circumscribed luminal constrictions on: (1) postcapillary venules; (2) collecting veins; (3) where collecting veins merged with the spiral modiolar vein; (4) on the spiral modiolar vein itself. Circumscribed constrictions in arteries were not observed. In ET-1 injected animals focal contractions of collecting veins reduced luminal width by 13.4% +/- 2.9 (P < 0.01). In control rats, constrictions on venous casts were minimal and constrictions on arteries were not observed. The present study shows that ET-1 is involved in local control of cochlear blood flow in that it focally contracts cochlear veins. It is suggested that this might be due to the high affinity of ET-1 receptors and/or the large number of ET-1 receptors on contractile cells in venous walls. PMID- 9367228 TI - Morphological evidence of ototoxicity of the iron chelator deferoxamine. AB - Recent reports of the role of iron-catalyzed free radical formation in gentamicin ototoxicity and the successful attenuation of gentamicin ototoxicity by iron chelators led us to re-examine experimental material from a previously unpublished study of deferoxamine. Deferoxamine was injected i.m. into adult Japanese quail at either 300 or 750 mg/kg body weight for 30 days. Examination of sections from the basilar papilla at the light microscope level indicated that supporting cells were damaged after the lower drug dose, and that both supporting cells and hair cells were damaged after the higher drug dose. High, prolonged exposure to deferoxamine produced pathological changes similar to those seen in the basilar papilla after much lower, shorter doses of gentamicin. These results demonstrate that deferoxamine damages the quail inner ear and are consistent with the idea that the ototoxic actions of gentamicin may be mediated by iron chelation. PMID- 9367229 TI - Transient changes in cochlear potentials and DPOAEs after low-frequency tones: the 'two-minute bounce' revisited. AB - After exposure to a loud, non-traumatic low-frequency tone, auditory thresholds are elevated. Thresholds recover to normal in a non-monotonic manner, decreasing rapidly at first before increasing again, until they finally decrease monotonically towards normal. Although the transient elevation of thresholds after the initial improvement was originally called a 'bounce' by Hirsh and Ward (1952), Kemp (1986) suggests that the initial rapid recovery is the oddity: under some conditions a low-frequency tone can produce hypersensitivity in otoacoustic emissions, psychophysical thresholds, and perceived loudness (Kemp's 'bounce') without a later elevation of threshold (Hirsh and Ward's 'bounce'). Kemp also suggested that the transient hypersensitivity was caused by changes in the sensitivity of the active process within the cochlea. We have investigated the origin of this transient hypersensitivity (Kemp's bounce) in guinea pigs, recording cochlear potentials (CM, CAP, SP and EP) and otoacoustic emissions (DPOAEs at f2-f1, 2f1-f2, 2f2-2f1 and 3f1-2f2). Our results indicate that the bounce does not require neural activity, but is probably produced by non-neural cochlear mechanisms, possibly a transient decrease in the permeability of the organ of Corti which produces a small but significant change in standing current through outer hair cells. At least part of these changes, which are reduced as the stimulation frequency increases, and absent above 2 kHz, seem due to a small and transient movement of the cochlear partition towards scala tympani, probably due to a transient osmotic imbalance. PMID- 9367230 TI - Microphonic and DPOAE measurements suggest a micromechanical mechanism for the 'bounce' phenomenon following low-frequency tones. AB - Neural auditory thresholds in the guinea pig can be temporarily improved by up to 6 dB about 2 min after the cessation of an moderately intense low-frequency tone (Kirk and Patuzzi, 1997). We have measured changes in the f2-f1 distortion product otoacoustic emission (DPOAE) and low-frequency microphonic potential in scala tympani before, during and after a low-frequency tone (200 Hz) to determine the cause of this so-called bounce phenomenon. In particular we have analysed the low-frequency microphonic waveform in detail to estimate changes in the maximal receptor current through the outer hair cells (OHCs), the sensitivity of the OHC forward transduction process and the change in OHC operating point on the mechano electrical transduction transfer curve. Our results indicate that a 200 Hz tone changes the maximal current and sensitivity of the OHCs minimally, but more importantly, it transiently changes the operating point on the OHC transfer curve. In particular, the operating point changes are consistent with a movement of the OHC stereocilia away from the OHC basal body at the peak of the bounce. These changes detected using the microphonic potential are associated with changes in the level of the f2-f1 DPOAE that correlate well with the electrical measurements. We suggest that the shift in operating point is largely responsible for the increase in cochlear sensitivity, and is due to a disruption of the salt balance within the cochlea during the intense low-frequency tone. PMID- 9367231 TI - ATP-induced cochlear blood flow changes involve the nitric oxide pathway. AB - Although control mechanisms of cochlear blood flow (CBF) have been intensively studied since laser Doppler flowmetry was introduced for CBF measurement in animals and humans, the role of adenosine 5'-triphosphate (ATP) in CBF regulation is not known. Since ATP is a potent vasoactive agent in other organs, the aim of this study is to examine ATP-induced changes in CBF and to test whether the nitric oxide pathway is involved in ATP-induced CBF changes. The anterior inferior cerebellar artery (AICA) of anesthetized pigmented guinea pigs was exposed, and ATP was perfused into the AICA. For CBF measurement, the bulla was opened and the 0.7 mm laser probe of a Perimed PF2B flowmeter was positioned on the basal turn of the cochlea. AICA perfusion of an ATP solution caused dose dependent transient CBF increases. The maximum CBF increase induced was 220% of the baseline. In some animals, CBF showed a dual effect; a transient decrease followed by a longer-lasting increase. The perfusions of sodium nitroprusside (SNP) also resulted in dose-dependent CBF changes. The intravenous application of N(omega)-nitro-L-arginine methyl ester (L-NAME) significantly attenuated ATP induced CBF increases, and enhanced ATP-induced decreases, but did not affect SNP induced CBF changes. The ATP-induced CBF responses indicate that ATP plays a role in CBF regulation. The biphasic characteristic of the ATP-induced CBF change suggests the involvement of both P2x- and P2y-subtype purinoceptors. That L-NAME caused attenuation of the ATP-induced CBF increase implies that the ATP-induced CBF increase is mediated by the release of endothelium-derived relaxing factor, nitric oxide, following activation of endothelial P2y-purinoceptors in the cochlear vascular bed and/or cochlear supplying vessels. PMID- 9367232 TI - Expression of the nicotinic acetylcholine receptor subunit, alpha9, in the guinea pig cochlea. AB - Acetylcholine is a major neurotransmitter of the cochlear efferent system. Based on its high level of expression in hair cells, the recently cloned nicotinic receptor subunit, alpha9 [Elgoyhen et al., Cell 79 (1994) 705-715], is likely to be the postsynaptic receptor for acetylcholine in hair cells either as a homomeric complex or with other subunits yet to be identified. To further study this receptor, we cloned and sequenced alpha9 cDNA from the guinea pig organ of Corti library [Wilcox and Fex, Hear. Res. 62 (1992) 124-126]. The sequence of the guinea pig alpha9 cDNA is similar to that of the rat, with identities of 85% and 89% at the nucleotide and amino acid levels, respectively. Most differences are in the cytoplasmic loop domain between the transmembrane segments 3 and 4. We also observed minor differences in the putative ligand binding regions. Pharmacological differences between acetylcholine receptors on outer hair cells of rat and guinea pig have been reported, and the minor structural changes we observe could account for these differences. Reverse transcription-polymerase chain reaction analysis showed a high expression of alpha9 in the organ of Corti while expression was low or not detected in the spiral ganglion. In situ hybridization histochemistry showed expression of alpha9 mRNA in both inner and outer hair cells, with much higher expression in outer hair cells than in inner hair cells. In the inner hair cell, silver grains were more abundant over the basal part of the cell than over the apical part. Immunocytochemistry showed a pattern of distribution of the alpha9 protein similar to that seen for mRNA with in situ hybridization. Immunolabeling was most intense at the bases of both inner and outer hair cells. To determine the effect of hair cell loss on alpha9 expression, hair cells were destroyed by either systemic or local application of kanamycin. This treatment led to a down regulation of alpha9 in hair cells; this down regulation appeared to precede hair cell degeneration. In the spiral ganglion, a transient up regulation of alpha9, as determined by RT-PCR, was seen 4-6 weeks after kanamycin treatment. PMID- 9367233 TI - Endothelin-A receptors mediate vasoconstriction of capillaries in the spiral ligament. AB - The purpose of this study was to determine whether endothelin-1 (ET-1), endothelin-2 (ET-2) or endothelin-3 (ET-3) alter the vascular diameter of capillaries in the spiral ligament. Changes in vascular tone were measured in capillaries from the isolated spiral ligament in vitro. Capillaries were occluded on one end and opened on the other end. Red blood cells trapped in the capillaries served as markers for a luminal volume defined by the red cell itself, the capillary wall and the occluder. Movement of the red cell toward the open end was taken as evidence for vasoconstriction and movement of the red cell toward the occluder was taken as evidence for vasodilation. The inner diameter of the capillaries was 7.0 microm and decreased maximally by a factor of 0.8 in response to ET-1 and ET-2 (both 10(-8) M). Vasoconstriction induced by ET-1 and ET-2 was concentration-dependent in the range between 10(-12) and 10(-8) M whereas ET-3 (10(-8) M) had no effect. The EC50s for ET-1 and ET-2 were 1.2 x 10( 10) M and 1.4 x 10(-9) M, respectively. Thus, the potency order was ET-1 > ET-2 >> ET-3. Vasoconstriction induced by ET-1 and ET-2 was completely inhibited by the competitive antagonist 10(-6) M BQ-123 (cyclic D-Asp-L-Pro-D-Val-L-Leu-D Trp). Vasoconstriction induced by ET-1 or ET-2 continued for more than 1 min after removal of agonist from the perfusate. Rapid vasodilation of capillaries preconstricted by ET-1 was observed in response to 10(-3) M sodium nitroprusside. Sodium nitroprusside, however, had no significant effect on the vascular diameter of resting capillaries. These results demonstrate that capillaries in the spiral ligament can constrict and the endothelin-mediated vasoconstriction occurs via ET(A) receptors. PMID- 9367234 TI - Response of the primary auditory cortex to electrical stimulation of the auditory nerve in the congenitally deaf white cat. AB - Neural activity plays an important role in the development and maintenance of sensory pathways. However, while there is considerable experience using cochlear implants in both congenitally deaf adults and children, little is known of the effects of a hearing loss on the development of the auditory cortex. In the present study, cortical evoked potentials, field potentials, and multi- and single-unit activity evoked by electrical stimulation of the auditory nerve were used to study the functional organisation of the auditory cortex in the adult congenitally deaf white cat. The absence of click-evoked auditory brainstem responses during the first weeks of life demonstrated that these animals had no auditory experience. Under barbiturate anaesthesia, cortical potentials could be recorded from the contralateral auditory cortex in response to bipolar electrical stimulation of the cochlea in spite of total auditory deprivation. Threshold, morphology and latency of the evoked potentials varied with the location of the recording electrode, with response latency varying from 10 to 20 ms. There was evidence of threshold shifts with site of the cochlear stimulation in accordance with the known cochleotopic organisation of AI. Thresholds also varied with the configuration of the stimulating electrodes in accordance with changes previously observed in normal hearing animals. Single-unit recordings exhibited properties similar to the evoked potentials. Increasing stimulus intensity resulted in an increase in spike rate and a decrease in latency to a minimum of approximately 8 ms, consistent with latencies recorded in AI of previously normal animals (Raggio and Schreiner, 1994). Single-unit thresholds also varied with the configuration of the stimulating electrodes. Strongly driven responses were followed by a suppression of spontaneous activity. Even at saturation intensities the degree of synchronisation was less than observed when recording from auditory brainstem nuclei. Taken together, in these auditory deprived animals basic response properties of the auditory cortex of the congenitally deaf white cat appear similar to those reported in normal hearing animals in response to electrical stimulation of the auditory nerve. In addition, it seems that the auditory cortex retains at least some rudimentary level of cochleotopic organisation. PMID- 9367236 TI - Detection of signals having expected and unexpected temporal structures. AB - Two experiments used a variant of the 'probe-signal' method [Greenberg and Larkin, J. Acoust. Soc. Am. 44 (1968) 1513-1523] to examine the effect of expectedness on the detection of signals having fixed frequencies but uncertain temporal structures. Expectedness was manipulated by presenting one signal on 75% of the trials and the other on only 25% of trials. Experiment 1 measured sensitivity (d') to 4000-Hz sinusoidal signals having durations of 10 ms and 295 ms. The results confirmed the finding by Wright and Dai [J. Acoust. Soc. Am. 95 (1994) 931-938] that sensitivity was poorer when the duration of the signal was unexpected. The second experiment used two signals having the same overall duration: six 10-ms 4000-Hz tone pulses with a 0-ms inter-pulse interval, and two 10-ms 4000-Hz pulses separated by 40 ms. Again, sensitivity was lower when the temporal structure of the signal was unexpected. It is argued that this finding is inconsistent with 'long time constant' models of temporal integration, but can be accounted for by assuming that subjects combine information from a number of short 'looks' at the signal, with the number and temporal location of these looks being influenced by its expected temporal structure. PMID- 9367235 TI - Correspondence between middle frequency auditory loss in vivo and outer hair cell shortening in vitro. AB - The aromatic hydrocarbon, toluene, has been reported to disrupt auditory system function both in occupational epidemiological and in laboratory animal investigations. This agent, along with several other organic solvents, impairs hearing preferentially at middle frequencies - a finding that distinguishes these agents from the traditional high frequency impairment observed with ototoxic drugs such as aminoglycoside antibiotics and cisplatin. Prior investigations performed in vivo have identified the outer hair cell as a probable target for toluene exposure. The purpose of this investigation was to determine directly whether outer hair cells isolated from the guinea pig cochlea show morphological alterations consistent with the toxic response seen in physiological studies with toluene exposure. The effect of toluene superfusion on outer hair cell shortening was assessed for cells harvested from different locations within the cochlea. Control studies included assessment of cell shortening among outer hair cells exposed to trimethyltin and cells exposed to benzene. Trimethyltin disrupts high frequency hearing preferentially and benzene does not produce hearing loss in vivo. Toluene at a concentration of 100 microM produced a marked shortening of outer hair cells although the effect was significantly greater among cells isolated from the apical half of the cochlea than from the basal half of the cochlea. By contrast, trimethyltin at the same concentration produced a preferential shortening among outer hair cells from the base of the cochlea. Benzene (100 microM) did not disrupt outer hair cell length of cells harvested from the apex. The results indicate that intrinsic features of outer hair cells contribute significantly to the site of ototoxic impairment observed in vivo for toluene. PMID- 9367237 TI - Reduction in excitability of the auditory nerve following electrical stimulation at high stimulus rates. II. Comparison of fixed amplitude with amplitude modulated stimuli. AB - We have previously shown that acute electrical stimulation of the auditory nerve using charge-balanced biphasic current pulses presented continuously can lead to a prolonged decrement in auditory nerve excitability (Tykocinski et al., Hear. Res. 88 (1995), 124-142). This work also demonstrated a reduction in electrically evoked auditory brainstem response (EABR) amplitude decrement when using an otherwise equivalent pulse train with a 50% duty cycle. In the present study we have extended this work in order to compare the effects of electrical stimulation using both fixed amplitude electrical pulse trains and amplitude modulated (AM) pulse trains that more accurately model the dynamic stimulus paradigms used in cochlear implants. EABRs were recorded from guinea pigs following acute stimulation using AM trains of charge-balanced biphasic current pulses. The extent of stimulus-induced reductions in the EABR were compared with our previous results using either fixed amplitude continuous, or 50% duty cycle pulse trains operating at 0.34 microC/phase (2 mA, 170 micros/phase) at 400 or 1000 pulses/s (Tykocinski et al., Hear. Res. 88 (1995) 124-142). The AM pulse train, operating at the same rates, was based on a 1-s sequence of the most extensively activated electrode of a Nucleus Mini-22 cochlear implant using the SPEAK speech processing strategy exposed to 4-talker babble, and delivered the same total charge as the fixed amplitude 50% duty cycle pulse train. Two hours of continuous stimulation induced a significant, rate-dependent reduction in auditory nerve excitability, and showed only a slight post-stimulus recovery for monitoring periods of up to 6 hours. Following 2 or 4 h of stimulation using an otherwise equivalent pulse train with a 50% duty cycle or the AM pulse train, significantly less reduction in the EABR was observed, and recovery to pre-stimulus levels was generally rapid and complete. These differences in the extent of the recovery between the continuous waveform and both the 50% duty cycle and AM waveforms were statistically significant for both 400 and 1000 pulses/s stimuli. Consistent with our previous results, the stimulus changes observed using AM pulse trains were rate dependent, with higher rate stimuli evoking more extensive stimulus-induced changes. The present findings show that while stimulus-induced reductions in neural excitability are dependent on the extent of stimulus-induced neuronal activity, the use of an AM stimulus paradigm further reduces post-stimulus neural fatigue. PMID- 9367238 TI - Calbindin D-28k immunoreactivity in the medial nucleus of the trapezoid body declines with age in C57BL/6, but not CBA/CaJ, mice. AB - This study compared calbindin D-28k immunoreactivity in the medial nucleus of the trapezoid body (MNTB) in young (3-4 month old) and old (24-26 month old) CBA/CaJ mice, and young (3-4 month old), middle-aged (6.5-8.5 month old), and old (24-29 month old) C57BL/6 mice. C57BL/6 mice exhibit progressively more severe peripheral (sensorineural) hearing loss between 4 and 12 months of age, whereas CBA/CaJ mice show little change in peripheral sensitivity until very late in life. We obtained auditory brainstem response audiograms on all subject mice. Old CBA mice were selected for study whose audiograms matched those of young CBA and C57 controls. Middle-aged C57 mice showed elevated thresholds indicative of peripheral degeneration. Brain sections were reacted with anti-calbindin D-28k (CB). Staining patterns in Nissl and anti-CB material were characterized and cells were counted. We found no significant change in the number of CB+ cells or the total number of cells in the MNTB of old CBA mice compared to young controls. However, the mean number of CB+ cells decreased by 11% in middle-aged, and by 14.8% in old C57 mice. Since the decline in C57 mice was significant by 6.5-8.5 months of age, the decrease could be the consequence of a loss of input from the cochlear nucleus where cell numbers are known to decline by this age in this strain. The total number of neurons in MNTB assessed from Nissl material showed a more modest 7.1% decline with age in C57 mice, implying that the greater loss of CB immunoreactive cells with age cannot be completely attributed to a reduction in the total number of cells. PMID- 9367239 TI - Effect of anesthetic agents and middle ear pressure application on distortion product otoacoustic emissions in the gerbil. AB - The functional status of the middle ear system has a crucial importance in the measurements of distortion product otoacoustic emissions (DPOAEs), because each emission signal has to be detected indirectly in the external canal. It was observed that DPOAEs were scarcely detectable in the gerbil anesthetized with pentobarbital. On the other hand, when ketamine was used as an anesthetic, the DPOAE levels were generally high. The differences in the effects of these anesthetic agents on the DPOAEs became less clear when the tympanic bulla was opened. This strongly suggests that the effects might be due to a modification of the middle ear pressure. This study was designed to elucidate the mechanisms of the effects of these anesthetics on the DPOAEs. Comparing the effects of pentobarbital and those of pressure application to the middle ear on the frequency characteristics of DPOAEs, the following conclusions emerged: (1) pentobarbital administration causes negative middle ear pressure in the gerbil; (2) the generated pressure strongly reduces DPOAE conduction through the middle ear; and thus (3) proper selection of anesthetic agents is very important in gerbil experiments that involve OAE measurements. PMID- 9367240 TI - The columnar and layer-specific response properties of neurons in the primary auditory cortex of Mongolian gerbils. AB - The columnar and layer-specific response properties of neurons in the primary auditory cortex (AI) of Mongolian gerbils were studied using single-unit recordings of responses to tone-burst stimuli presented to the ear contralateral to the recording side. During near-radial microelectrode penetrations of the AI in 100-microm steps, the best frequency (BF), best threshold (BT), best amplitude (BA), latency, tuning curve and Q10dB were recorded. Neurons encountered during single penetrations showed similar BFs, indicating a columnar frequency organization, but their latencies and Q10dBs differed. The BAs and BTs recorded within single penetrations often showed a similar value in the middle cortical layers. The latencies and Q10dBs of these neurons exhibited a tendency toward a layer-specific distribution. The latencies of neurons located in layers I-V were longer than those located in layer VI. The Q10dBs of neurons located in layers III and IV were higher than those located in layers I and VI. These results are almost consistent with those of previous studies on frequency representation, and indicated the existence of an integrative mechanism of frequency processing in the AI. This is the first study in which a layer-specific, partially columnar organization for stimulus amplitude is described. PMID- 9367241 TI - Two types of K+ currents in marginal cells cultured from rat stria vascularis. AB - Membrane currents in marginal cells cultured from rat stria vascularis were studied using the whole-cell patch-clamp technique. Two types of voltage dependent whole-cell currents were observed in the voltage range from -150 mV to +50 mV: an outwardly rectifying current and an inwardly rectifying current. The outwardly rectifying current, which was activated by depolarizing pulses more positive than -30 mV, was sensitive to TEA (20 mM) and relatively not to Ba2+ (0.5 mM). Tail current analysis revealed that the outward currents were primarily K+-selective. The conductance of the current was half-maximal at 0.5 mV and a substantial portion of current was not inactivated by the depolarizing prepulses from -30 mV to +20 mV. The inwardly rectifying current with rapid exponential activation was observed with hyperpolarizing voltage pulses. The zero-current potential of this current was dependent on extracellular K+ concentration. In contrast to the outwardly rectifying current, this current was blocked by extracellular application of Ba2+, not by TEA. The conductance of this current increased with the increase in external K+ concentration. Our data suggest that marginal cells cultured from rat stria vascularis express at least two types of voltage-dependent K+ currents which may serve as K+ secretory pathways into endolymph. PMID- 9367243 TI - Distortion product otoacoustic emissions in the C57BL/6J mouse model of age related hearing loss. AB - One of the earliest histopathological changes associated with age-related hearing loss appears to be the disruption of outer hair cells (OHCs). To evaluate age related changes in OHC function, distortion product otoacoustic emissions (DPOAEs) were recorded in the young and aging C57BL/6J mouse. Starting in young adulthood, the C57 mouse displays age-related elevation of auditory brainstem response thresholds, beginning in the high frequencies and progressing toward lower frequencies. The 2f1-f2 DPOAEs of mice between 2 and 20 months of age were examined for f2s between 8 and 16 kHz. In this octave region, the features of 2f1 f2 DPOAEs in the 2-month-old C57 mouse were comparable to those described for non murine rodents in the literature in terms of optimum f2/f1 ratio, optimum primary level difference, input/output (I/O) function features and microstructure. It was determined that f2/f1 = 1.2 and L1-L2 = 20 dB were optimal stimulus parameters for investigation of the effects of age on C57 DPOAEs. Age-related changes in DPOAE I/O functions consisted of a right shift (i.e. increased DPOAE detection thresholds), disappearance of 'notches' and shallowing of the slopes after 8 months of age. As DPOAE I/O functions continued to shift to the right and DPOAE levels decreased with age, the appearance of I/O functions became complex to include regions of steep or shallow slopes and plateaus. The present results suggest that the age-related elevation of auditory thresholds in the C57 mice is associated with substantial progressive changes in OHC function. PMID- 9367242 TI - Quantitative relationship of carboplatin dose to magnitude of inner and outer hair cell loss and the reduction in distortion product otoacoustic emission amplitude in chinchillas. AB - The outer hair cells (OHCs) are thought to be the dominant source of distortion product otoacoustic emissions (DPOAEs) in the mammalian cochlea; however, little is known about the quantitative relationship between reduction in DPOAE amplitude and the degree of inner hair cell (IHC) and OHC loss. To examine this relationship, we measured the DPOAE input/output functions in the chinchilla before and after destroying the IHCs and/or OHCs with carboplatin. Low-to moderate doses (38-150 mg/kg, i.p.) of carboplatin selectively destroyed some or all of the IHCs along the entire length of the cochlea while sparing the OHCs. Selective loss of all the IHCs had little effect on DPOAE amplitude as long as the OHCs were present. With high doses of carboplatin (200 mg/kg, i.p.), there was complete destruction of IHCs plus massive OHC loss that decreased from the base towards the apex of the cochlea. OHC loss resulted in a large decrease in DPOAE amplitude. DPOAE amplitude at 9.6 kHz decreased at the rate of 4.1 dB for every 10% loss of OHCs. At 7.2 and 4.8 kHz, DPOAE amplitude decreased 3.1 dB and 2.4 dB per 10% OHC loss, respectively. These results indicate that OHCs are the dominant source of DPOAEs. PMID- 9367244 TI - Behavioral measures of vowel sensitivity in Mongolian gerbils (Meriones unguiculatus): effects of age and genetic origin. AB - Absolute thresholds for complex vowel stimuli were compared in Mongolian gerbils (Meriones unguiculatus) as a function of age and genetic origin. For a group of 12-month-old 'domestic' gerbils obtained from Tumblebrook Farms, lowest thresholds averaging 14 dB SPL occurred for the vowel /alpha/, which had its most intense formant (F1) at 730 Hz. Thresholds increased to 22 dB SPL for /i/, which had its two most intense formants (F1 and F3) at 270 and 3000 Hz, respectively. Highest thresholds of 30 dB SPL occurred for /u/, which had its most intense formant (F1) at 300 Hz. Thresholds increased by about 10 dB per year through the ages of 12-36 months, with most of the loss occurring for /alpha/ and /u/. The domestic gerbils' /alpha/ thresholds corresponded well to those measured in aging gerbils in electrophysiological studies. Vowel thresholds were also measured in a group of first-generation offspring of 'wild' gerbils imported from Asia, first tested at the ages of 18-24 months. Thresholds were similar to those of the 12 month-old domestic gerbils, and showed no hearing loss with age up to 36 months. The wild gerbils were also free of ear impactions, which commonly occurred in the domestic gerbils. The hearing loss with age in the domestic gerbils may have a genetic basis, and might be due to inbreeding in the domestic strain, in contrast to the hybrid vigor of the wild gerbils. PMID- 9367245 TI - Effects of stimulus configuration on psychophysical operating levels and on speech recognition with cochlear implants. AB - Effects of electrode configuration and pulse duration on operating levels and on speech recognition performance were studied in a group of 14 adult postlingually deaf human subjects with Nucleus cochlear implants. The operating levels (based on detection threshold and maximum comfortable loudness levels) for narrowly spaced bipolar (BP) stimulation were found to be about 11 dB higher on average than those for widely spaced bipolar (BP+6) or monopolar (MP1) stimulation. Operating levels for common ground (CG) stimulation fell between those for BP and BP+6; the difference between BP and CG detection thresholds depended on pulse duration. Variation in detection thresholds and maximum comfortable loudness levels across the electrode array (electrodes 1-15) was larger for BP and CG stimulation than for BP+6 or MP1 stimulation, suggesting narrower spread of activation for the BP and CG configurations despite the higher current levels. Speech recognition performance was tested using experimental processor configurations. Among the experimental electrode configurations tested (BP, CG, and BP+6), the highest speech recognition scores were obtained with the BP+6 configuration in many subjects. Effects of pulse duration on speech recognition were less consistent and usually smaller than the effects of electrode configuration. The results indicate that electrode configuration is an important variable determining speech recognition performance and suggest that restriction of the size of neural population activated by individual channels of the prosthesis is not necessarily advantageous. PMID- 9367246 TI - Hypothalamic-pituitary-adrenocortical responses to single vs. repeated endotoxin lipopolysaccharide administration in the rat. AB - Lipopolysaccharide (LPS) is a potent stimulator of the hypothalamic-pituitary adrenal (HPA) axis. However, the alteration in the HPA axis responsiveness and brain corticosteroid receptor levels during long-term administration of LPS has not been studied well. The present study was designed to examine the effect of single vs. repeated intraperitoneal (i.p.) LPS injection on the HPA axis and brain corticosteroid receptor levels in male Wistar rats. In addition, c-fos mRNA expression was examined in the hypothalamic paraventricular nucleus (PVN) and brainstem catecholaminergic nuclei such as the locus coeruleus (LC) and nucleus tractus solitarius (NTS), the sites known to be involved in LPS-induced HPA axis stimulation. Rats that had received i.p. LPS injection for 6 consecutive days (6 LPS group) had similar levels of plasma adrenocorticotropin (ACTH) and corticosterone (CORT) compared to animals that had received i.p. saline (6-saline group). A single injection of LPS to the 6-saline group (6-saline + challenge) resulted in a substantial increase in plasma ACTH and CORT at 2 h, whereas an additional injection of LPS to the 6-LPS group (6-LPS + challenge) showed less of an increase. As determined by in situ hybridization histochemistry, proopiomelanocortin (POMC) mRNA levels in the anterior pituitary (AP) and corticotropin-releasing hormone (CRH) mRNA levels in the PVN were higher in the 6 LPS than in the 6-saline group. A single injection of LPS to the 6-saline group resulted in a significant increase in AP POMC mRNA and PVN CRH mRNA at 2 h, while injection of LPS to the 6-LPS group showed no additional increase in these levels. C-fos mRNA expression was prominent in the PVN, LC, and NTS following a single injection of LPS, but not following repeated LPS injection. These results suggest that stimulatory input into the PVN decreased following repeated LPS injection. Furthermore, type II glucocorticoid receptor (GR) mRNA levels in the 6 LPS and 6-LPS + challenge groups were decreased in the hippocampus, but not in the PVN or AP. Adrenalectomy with 40% CORT pellet replacement restored ACTH responses following repeated LPS injections to levels similar to those following a single LPS injection. Decreased hippocampal GR mRNA may contribute to the elevated PVN CRH mRNA levels in the 6-LPS group. Nevertheless, inhibition of the pituitary ACTH response by glucocorticoids and reduced hypothalamic drive are partly responsible for decreased pituitary-adrenal responsiveness following repeated LPS injection. PMID- 9367247 TI - Loss of dopamine terminals in the medial prefrontal cortex increased the ratio of DOPAC to DA in tissue of the nucleus accumbens shell: role of stress. AB - We examined whether dopamine depletion in the medial prefrontal cortex of the rat differentially affects basal and evoked dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) content in the subareas of the neostriatum and nucleus accumbens. Loss of approximately 80% of tissue dopamine content in the medial prefrontal cortex did not significantly alter basal tissue concentrations of dopamine or DOPAC or the DOPAC:dopamine ratio in either the nucleus accumbens core or shell or the medial or lateral neostriatum. However, tail pressure stress significantly increased the DOPAC:dopamine ratio in the nucleus accumbens shell of lesioned rats. Because dorsal and ventral areas of the medial prefrontal cortex preferentially innervate the core and shell, respectively, we sought to determine whether the selective effect of lesions on dopamine terminals in the shell of the nucleus accumbens are paralleled by greater dopamine loss in the ventral medial prefrontal cortex. 6-Hydroxydopamine decreased tissue concentrations of dopamine in both the dorsal (-74%) and ventral medial prefrontal cortex (-68%). In lesioned rats, few tyrosine hydroxylase-immunoreactive fibers remained in the dorsal medial prefrontal cortex whereas a dense innervation remained in the ventralmost area. The present data suggest that the influence of mesocortical dopamine neurons on the dopamine projection to the nucleus accumbens shell is expressed only under conditions of stress. Furthermore, lesion-induced alterations in dopamine neurons projecting to the nucleus accumbens shell are not due to a more extensive loss of dopamine terminals in the ventral than in the dorsal medial prefrontal cortex. PMID- 9367248 TI - Modulation of the cardiac baroreflex following reversible blockade of the parabrachial nucleus in the rat. AB - The parabrachial nucleus (PBN) has a prominent anatomical connection with the nucleus of the solitary tract as well as other central baroreflex centres which suggests a role for the PBN in the regulation of this cardiovascular reflex. This study examined the effects of a reversible, bilateral blockade of the PBN on the cardiac baroreflex. Male Sprague-Dawley rats were anesthetized with sodium butabarbitol and instrumented to monitor blood pressure and heart rate and for the intravenous administration of drugs. The cardiac baroreflex was evoked using bolus intravenous injections of phenylephrine (PE) and sodium nitroprusside (NaNp) at various doses and a graph of baroreflex sensitivity was constructed. Bilateral microinjections of the reversible anesthetic, lidocaine (5%, 300 nl), into the PBN did not significantly change baseline blood pressure or heart rate when compared to microinjections of saline (0.9%, 300 nl) into the PBN. The pressor or depressor responses evoked by bolus injections of PE or NaNp, respectively, were not significantly affected by the bilateral pretreatment of the PBN with lidocaine when compared to saline controls. However, approximately 30 min following lidocaine injection, the amplitudes of both the evoked-reflex bradycardia and reflex tachycardia were significantly increased by approximately 98%. The cardiovascular responses to various doses of PE and NaNp were graphed and baroreflex sensitivity curves were constructed. This graph showed an increased slope of the baroreflex sensitivity curve following lesions of the PBN. Reflex changes in heart rate returned to pre-lidocaine injection levels after approximately 2 h. The results of the present investigation suggest that the PBN participates in the modulation of the cardiac baroreflex which in turn suggests a role for this nucleus in the central integration of cardiovascular reflex function. PMID- 9367249 TI - Cerebrovascular consequences of altering serotonergic transmission in conscious rat. AB - Many therapeutic strategies aim at altering serotonin brain levels. However, serotonin (5-HT) is known to influence the cerebral circulation. The purpose of this study was to determine the effects of acutely decreasing intracerebral serotonin release upon cerebral blood flow and cerebrovascular reactivity to hypercapnia in conscious rats. To this end, (1) we analyzed the time-course of cortical blood flow changes measured with laser-Doppler flowmetry following injection of 0.1 mg kg(-1) 8-OHDPAT (5-HT1A agonist), and (2) we evaluated the cerebrovascular reactivity to hypercapnia using a quantitative multiregional diffusible tracer technique 5 and 60 min following 8-OHDPAT administration. 8 OHDPAT induced a rapid and transient increase in cortical blood flow (+34%) that was prevented totally by WAY100135 (5-HT1A antagonist) pre-treatment. Five min following 8-OHDPAT administration, the cerebrovascular responsiveness to hypercapnia was increased significantly in striatum (+27%) and fronto-parietal cortex (+61%). This result is consistent with a vasoconstrictor role of the serotonergic system that becomes manifest during hyperemic conditions. PMID- 9367250 TI - Membrane properties of deep dorsal horn neurons from neonatal rat spinal cord in vitro. AB - Whole-cell patch-clamp recordings were undertaken to characterize and compare the membrane properties of deep dorsal horn neurons in transverse slices of rat lumbar spinal cord in two age groups, postnatal days (P) 3-6 and 9-16. In both age groups, significant correlations were observed between membrane time constant and cell resistance and between action potential height and its duration at half maximal amplitude. Cell resistance and action potential half-width values were lower in the P9-16 age group. Neurons were divided into four categories based on their firing properties in response to intracellular current injection: single spike, phasic firing, repetitive firing, and delayed firing. The distribution of neurons within these categories was similar in both age groups which suggests that the firing properties of deep dorsal horn neurons are functionally differentiated at an early postnatal age. PMID- 9367251 TI - Metabotropic glutamate receptors modulate synaptic transmission in the perforant path: pharmacology and localization of two distinct receptors. AB - Metabotropic glutamate receptors (mGluRs) have emerged as an interesting family of eight different receptor subtypes that can be divided into three groups according to their pharmacology and sequence similarity. In the present study, the specific mGluR agonists (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid ((1S,3R)-ACPD) and L(+)-2-amino-4-phosphonobutyric acid (L-AP4) depressed field excitatory postsynaptic potentials (fEPSPs) in the rat dentate gyrus evoked by perforant path stimulation in a concentration-dependent, rapid and reversible manner (EC50: L-AP4 5.9 +/- 1.6 microM, (1S,3R)-ACPD 80 +/- 34 microM). In a 'paired-pulse' stimulation protocol, the first fEPSP showed a stronger reduction, resulting in 'paired-pulse' facilitation. The effects of L-AP4 but not of (1S,3R) ACPD could be antagonized by the group III mGluR antagonists (S)-2-amino-2-methyl 4-phosphonobutanoic acid (MAP4) and (RS)-alpha-methyl-4-phosphonophenylglycine (MPPG). Moreover, (1S,3R)-ACPD was still potently depressing fEPSPs after preperfusion of near saturating concentrations of L-AP4. Together, the results suggest that both substances act on different mGluRs. The effects of (1S,3R)-ACPD could not be further differentiated by selective group I or group II mGluR agonists. Although (2S,1'S,2'S)-2-carboxycyclopropylglycine (L-CCG-I) blocked fEPSPs at concentrations >> 1 microM, these effects, as well as L-AP4 effects, were potently antagonized by MAP4. This suggests that mGluR8 might be responsible for the actions of L-AP4 and L-CCG-I. The two different mGluRs showed a distinct distribution when fEPSPs were recorded simultaneously in the outer and middle molecular layer (OML/MML): The L-AP4 sensitive receptor, possibly mGluR8, seems to be located in the OML while (1S,3R)-ACPD showed its main effect in the MML. PMID- 9367252 TI - Functional characterization of a kindling-like model of ethanol withdrawal in cortical cultured neurons after chronic intermittent ethanol exposure. AB - Chronic ethanol exposure has been reported to alter NMDA and GABA(A) receptor function and gene expression in brain regions of animals and mammalian cultured cortical neurons. In the present study, we investigated the effects of another model of chronic, but intermittent, ethanol treatment (CIE) on GABA(A) and NMDA receptor systems in cortical neurons. CIE (50 mM ethanol, 12 h exposure/12 h withdrawal, 5 cycles) exposure produced increased [3H]MK-801 binding and diazepam insensitive binding sites as measured by [3H]Ro15-4513 binding to cortical cultured neuronal membranes, at 0 h following the last treatment cycle relative to control neurons. The NMDA mediated increase in intracellular calcium [Ca2+]i was also increased following similar CIE treatment. CIE treatment also increased the ability of pentylenetetrazol (PTZ) to inhibit GABA mediated 36Cl- influx relative to control neurons. These effects were not reversible following 1 week ethanol withdrawal, implying enhanced sensitivity of PTZ to inhibit GABA(A) receptor mediated inhibition, and an increased NMDA receptor function in CIE treated cortical neurons. These alterations are consistent with the behavioral studies in animals, and suggest that both GABA(A) and NMDA receptors play an important role in ethanol withdrawal following either chronic or CIE exposure. Furthermore, this provides a feasible in vitro model for further biochemical and molecular studies of the mechanism underlying the CIE induced kindling-like phenomenon observed in humans. PMID- 9367253 TI - Increased dopamine turnover in the putamen after MPTP treatment in common marmosets. AB - The differences in dopamine turnover rate between the putamen and the caudate nucleus in the striatum lesioned by a neurotoxin 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP) were studied in the common marmoset, a small New World monkey. Systemic administration of MPTP damaged equally and dose-dependently nigrostriatal dopaminergic neurons projecting both to the caudate nucleus and the putamen. The compensatory increase of dopamine turnover, however, occurred more prominently in the putamen than in the caudate. The neural connection and function of the caudate nucleus and the putamen have been differentiated anatomically or physiologically. The compensatory increase of dopamine turnover rate is another different aspect of functions between the caudate nucleus and the putamen. Dopaminergic neurons projecting to the putamen showed more prominent cell loss than those projecting to the caudate in Parkinson's disease or related disorders. The selective augmented turnover rate of lesioned dopaminergic neurons might be, at least partly, involved with selective degeneration of nigrostriatal neurons projecting to the putamen. PMID- 9367254 TI - Mechanism of synchronized Ca2+ oscillations in cortical neurons. AB - Dissociated rat cortical neurons reassociate in vitro to form synaptically connected networks. Removal of Mg2+ from the extracellular medium then induces neurons in the network to undergo synchronized oscillations of cytoplasmic calcium. Previous studies have shown that these calcium oscillations involve the activation of NMDA receptors and that the rising phase of each calcium spike is coincident with a brief burst of action potentials (Robinson et al., Jpn. J. Physiol. 43 (Suppl. 1) (1993) S125-130; Robinson et al., J. Neurophysiol. 70 (1993) 1606-1616; Murphy et al., J. Neurosci. 12 (1992) 4834-4845). We have found that these calcium oscillations are dependent on an influx of extracellular calcium but are independent of mobilization of calcium from intracellular stores. The influx of extracellular Ca2+ occurs primarily through L-type voltage-gated calcium channels (VGCCs), since diltiazem inhibits calcium oscillations under all conditions. On the other hand, N-, P/Q-, and T-type VGCCs are not required for calcium oscillations, although inhibitors of these channels may act as partial antagonists. In addition to removal of Mg2+, oscillations can also be induced by the inhibition of voltage-gated K+ channels with 4-aminopyridine (4-AP), a treatment known to increase neurotransmitter release. In the presence of 4-AP, synchronized calcium oscillations become independent of NMDA receptor activation, although they continue to require activation of AMPA/KA receptors. A model for the mechanism of neuronal calcium oscillations and the reason for their synchrony is presented. PMID- 9367255 TI - Expression of beta-calcitonin gene-related peptide in axotomized rubrospinal neurons and the effect of brain derived neurotrophic factor. AB - The mRNA levels for alpha- and beta-calcitonin gene-related peptide (CGRP) in rat rubrospinal neurons were studied by in situ hybridization 3, 7, 14, 28 and 56 days following cervical spinal hemisection. CGRP-like immunoreactivity (LI) in the rubrospinal neurons and the rubrospinal tract in cervical spinal cords were examined using immunohistochemistry. There was almost no signal for alpha- and beta-CGRP mRNAs and undetectable level of CGRP-LI in the rubrospinal neurons ipsilateral to cervical spinal hemisection (control side). Fourteen days after spinal hemisection, the rubrospinal neurons contralateral to cervical hemisection (axotomized side) showed CGRP-LI in their cell bodies, and CGRP containing fibers were observed in the lateral funiculi just proximal, but not distal, to the injury sites. In situ hybridization showed upregulation of beta-CGRP mRNA in a subpopulation of the rubrospinal neurons on the axotomized side. The proportion of beta-CGRP mRNA-expressing neurons reached its maximum (approximately 19%) 4 days following axotomy and slowly decreased to about 5% 56 days after axotomy. The percentage of alpha-CGRP mRNA-expressing neurons was much lower than that of beta-CGRP mRNA (maximum about 2.6% 4 days after axotomy) and not significantly different from the control side throughout the time period studied. These data indicate that axotomy induces de novo synthesis of the CGRP beta-subtype in rubrospinal neurons and that the beta-CGRP is transported to the injury site through the rubrospinal tract. In addition, we studied the effect of the intracerebral injections of brain derived neurotrophic factor (BDNF). BDNF treatment fully reversed the severe cell atrophy that followed axotomy and increased the number of neurons labeled for beta-CGRP mRNA, but did not increase the percentage of rubrospinal neurons expressing beta-CGRP mRNA. Thus, topical application of BDNF does not have direct modulatory effect on CGRP induction in axotomized neurons in the red nucleus. PMID- 9367256 TI - Neutral proteases and disruption of the blood-brain barrier in rat. AB - Blood-brain barrier disruption is common in many neurological diseases. Matrix metalloproteinases are induced in brain injury and increase capillary permeability by attacking the extracellular matrix around cerebral capillaries. Other neutral proteases are also increased in sites of secondary injury, and may contribute to the proteolysis of the blood-brain barrier. Therefore, we studied capillary permeability and histological tissue damage after intracerebral injection of neutrophil elastase, cathepsin G, heparatinase and plasmin. Adult rats were injected intracerebrally with an enzyme. After 1, 4 or 24 h, measurements were made of brain uptake of a radiolabeled tracer, [14C]sucrose. Enzymes that significantly increased capillary permeability were injected into other rats for histological assessment of tissue damage. Elastase increased capillary permeability significantly when compared with controls; maximal damage was seen at 4 h. Plasmin produced smaller increases in permeability at 4 h, exerting its maximal effect on sucrose uptake at 24 h. Cathepsin G had a small effect at 4 h. Heparitinase had no effect. Histologic examination of elastase injected brains at 24 h revealed multifocal perivascular and intraparenchymal acute hemorrhages accompanied by a polymorphonuclear cell infiltrate. Elastase injected brains were microscopically similar to saline-injected brains at 1 and 4 h. Plasmin produced fibrinoid changes in the blood vessels at 24 h, coinciding with the maximal increase in capillary permeability. We conclude that neutrophil elastase attacks the capillary extracellular matrix, causing extensive hemorrhage, while plasmin leads to increased vascular permeability and fibrinoid necrosis of blood vessel walls. Differential effects of neutral proteases released secondary to injury could be important in both the acute changes in blood vessel permeability and long-term alterations in vessel structure. PMID- 9367257 TI - Expression of a glutamate transporter subtype, EAAT4, in the developing human cerebellum. AB - A glutamate transporter subtype, EAAT4, is closely related to removal of glutamate from the synaptic cleft. Immunohistochemistry for EAAT4 demonstrated the specific distribution and localization of its expression in the developing human cerebellum. Purkinje cells showed faint EAAT4 immunostaining at 17 gestational weeks (GW), which became increasingly intense from 23 GW to the infantile period. In the late fetal to early infantile periods, Purkinje cells showed marked immunoreactivity. After the late infantile period, EAAT4 immunoreactivity was the same in extent as in the adult pattern. Its intracellular localization also changed with development. EAAT4 immunoreactivity was demonstrated in the short processes of Purkinje cells in the early embryonic period, in the cell bodies and dendrites in the late fetal to early infantile periods, and then in the spines after the late infantile period. In the adult cerebellum, immunoreactivity was detected strongly in the spines of Purkinje cells and weakly in the cell bodies. No immunoreactivity was found in the axons or axon terminals of the cells. Thus, the glutamate transporter exhibits developmental changes in its distribution in the cerebellum and its localization in Purkinje cells. EAAT4 immunoreactivity may be related to the dendritic arborization of cells in the molecular layer. PMID- 9367258 TI - Female social reproductive roles affect central monoamines. AB - Central monoamines display a variety of activation patterns in different social groups, and among males and females. We addressed three social conditions for female lizards of the species Anolis carolinensis: Isolated, paired with a mate, and in a group of 5 competing for one mate. Among those in a group, only 1 or 2 females exhibited recrudescing ovaries. Individuals paired with a mate (for one month) exhibited ovarian growth, isolated animals (initial controls) had quiescent ovaries. Reproductively dominant females had significantly greater telencephalic 5-HIAA, and serotonergic activation, as indicated by the ratio of 5 HIAA to 5-HT. Telencephalic HVA as well as the HVA/DA ratio were also significantly greater in dominant females compared to all other groups. In contrast, serotonergic activation in brainstem was elevated in subordinate females only. These results suggest that serotonergic activation in telencephalon, found only in dominant females, not in other reproductively active females, is a function of the unique social role of a dominant female, possibly combining submissive behaviors toward a male with dominance over other females and competition for access to that male. Dopaminergic activation in telencephalon, also found only in dominant females, may be related to aggressive interactions with other females. Activation of serotonin in brainstem, found in this study in subordinate females and previously in males [C.H. Summers and N. Greenberg, Activation of central biogenic amines following aggressive interaction in male lizards, Anolis carolinensis, Brain Behav. Evol., 45 (1995) 339-349], may be associated with subordinate social status. Monoamines, involved in social behaviors, appear to be regionally specialized for dominant and subordinate social roles, in males [C.H. Summers and N. Greenberg, Activation of central biogenic amines following aggressive interaction in male lizards, Anolis carolinensis, Brain Behav. Evol., 45 (1995) 339-349][T.R. Summers, E.T. Larson, A.L. Hunter, K.J. Renner, N. Greenberg and C.H. Summers, Amygdalar serotonin mediates long-term social roles following aggressive interaction, Soc. Neurosci. Abs., 22 (1996) 1147] and females. Dominant females exhibit unique social position, behavior and monoamine profile whereas subordinate females and males have a similar serotonergic response in this species. PMID- 9367259 TI - Peptide growth factors but not ganglioside protect against excitotoxicity in rat retinal neurons in vitro. AB - Glutamate is the major excitatory neurotransmitter in the retina, but excessive stimulation of its receptors leads to widespread neuronal stress and death. Both growth factors and gangliosides display important influences on responses to neuronal injury and degeneration. In this study, we have investigated the potential protective effects of two well characterized growth factors, epidermal and basic fibroblast growth factor (EGF and bFGF respectively), and the monosialoganglioside GM1, on cultured rat retinal neurons submitted to toxic levels of excitatory amino acids. Application of 1 mM glutamic acid reduced global neuronal viability by 80% when compared to control untreated cultures, whereas treatment with the glutamic acid agonist kainic acid (1 mM) led to specific, large decreases (75% reduction) in amacrine cell numbers. 24 h pretreatment with either EGF or bFGF (500 pM each) prevented the majority of excitatory amino acid-induced neuronal death, whereas similar treatment with 10( 5) M GM1 did not block neuronal degeneration. These findings demonstrate that EGF and bFGF act as neuroprotective agents against retinal excitotoxicity in vitro, whereas ganglioside GM1 is not effective in this particular paradigm. PMID- 9367260 TI - Locus coeruleus lesions decrease norepinephrine input into the medial preoptic area and medial basal hypothalamus and block the LH, FSH and prolactin preovulatory surge. AB - The aim of this work was to study the role of the dorsal noradrenergic ascending pathway (DNAP), which originates in the locus coeruleus (LC) on the preovulatory surge of luteinizing hormone (LH) follicle-stimulating hormone (FSH) and prolactin (PRL) by producing bilateral electrolytic lesions (cathodal or anodal) in this nucleus. LC lesions were placed at 11.00 h on proestrus in female rats with regular 4-day estrous cycles. Intact rats, sham-operated as well as animals with missed lesions served as controls. In Experiment I, anodal current was applied and hourly blood samples were withdrawn (from 13.00 to 17.00 h) via a jugular catheter from conscious, freely moving rats for determination of plasma LH, FSH and PRL concentrations. In Expt. II, Expt. I was repeated using cathodal current and collecting blood samples hourly from 13.00 to 18.00 h. In both experiments the animals were sacrificed on the next morning when the occurrence of ovulation was checked. The medial septal area (MSA), medial preoptic area (MPOA), and medial basal hypothalamus (MBH) were dissected and assayed for norepinephrine (NE), dopamine (DA) and 5-hydroxyindoleacetic acid (5-HIAA) content. Experiment III was performed in order to test if a hormonal discharge occurred immediately after lesion placement. Blood samples were collected immediately before and 15, 30, 60 and 90 min postoperatively (from 11.00 to 12.30 h). Either anodal or cathodal lesions blocked the proestrous surge of LH, FSH and PRL. The hypothesis that the lesions advanced or delayed these hormonal surges was rejected since we found no increases in the hormonal levels from 11.00 to 12.30 or from 13.00 to 18.00 h, and ovulation was not observed on the following morning in the lesioned animals. Since control, sham-operated and missed-lesion groups exhibited LH, FSH and PRL surges and ovulation, this blockage appears to be caused by the destruction of the LC neurons. Also, this blockade was correlated with a decrease in the NA content in the MPOA and MBH, but not in the MSA, whereas the DA and 5-HIAA content were not changed in all groups examined. The results lead us to suggest that the integrity of noradrenergic afferent input from the LC to luteinizing hormone-releasing hormone neurons in the MPOA and MBH is essential for triggering the preovulatory surge mechanisms for gonadotrophins and PRL. PMID- 9367261 TI - Testosterone is correlated with regional morphology of the human corpus callosum. AB - Theoretical speculation in humans (S.F. Witelson, Psychoneuroendocrinology 16 (1991) 131-153) and empirical findings in animals (R.H. Fitch, P.E. Cowell, L.M. Schrott, V.H. Denenberg, Int. J. Dev. Neurosci. 9 (1991) 35-38) suggest that testosterone (T) may play a significant role in the development of the corpus callosum (CC). However, there are currently no empirical studies directly relating T concentrations to callosal morphology in humans. The purpose of the present study was to investigate the relationship between free T concentrations as determined by radioimmunoassay, and the mid-sagittal area of the corpus callosum, as determined by magnetic resonance imaging (MRI). Subjects were 68 young adult (20-35 years), neurologically normal, right-handed males. All subjects underwent MRI and provided two samples of saliva for radioimmunoassay of T and cortisol. Anatomical regions of interest included total brain volume, left and right hemisphere volume and regional areas of the CC. CC regions were defined using two different measurement techniques, each dividing the CC into six sub sections. Anatomical measurements were performed blind with respect to the hormone levels of subjects. A significant positive correlation between T concentration and cross-sectional area of the posterior body of the CC was found. This finding was consistent across the two measurement techniques and was not attributable to individual differences in total brain volume. All correlations between cortisol and CC sub-regions were non-significant. The results of this study are consistent with the notion that T, at an earlier stage in development, may play a significant role in modulating cortical/callosal architecture in humans. PMID- 9367262 TI - Phosphorylation of microtubule-associated protein tau on Ser 262 by an embryonic 100 kDa protein kinase. AB - This study examined the phosphorylation of tau on Ser 262, within the first microtubule-binding domain, by a developmentally regulated 100 kDa protein kinase exhibiting significantly greater activity in the embryonic rat brain than in the adult rat brain. This protein kinase co-purified with microtubules and co immunoprecipitated with both tau and MAP-2. In addition to phosphorylating tau, MAP-2, and a Ser 262-containing peptide, the present protein kinase activity was shown to autophosphorylate as determined by the in-gel kinase assay in the absence of any protein or peptide polymerized into the matrix. Phosphorylation of tau with this protein kinase significantly reduced the tau-microtubule interaction, and the effect was significantly greater with microtubule-associated protein (MAP) preparations from embryonic brain than with preparations from the adult. Ser 262 is phosphorylated extensively in paired helical filament (PHF) tau from Alzheimer's disease (AD) brain, to a lesser extent in fetal tau, and only to a very minor extent in biopsy-derived human tau. Because the 100 kDa protein kinase activity phosphorylates Ser 262 and is higher in the fetal brain than the adult brain, it is hypothesized that an inappropriate re-expression and/or re activation of this or a similar developmentally regulated protein kinase could contribute to the phosphorylation of Ser 262 in PHF-tau, and thus play a role in the pathogenesis of AD. PMID- 9367263 TI - Relationship between motor unit short-term synchronization and common drive in human first dorsal interosseous muscle. AB - We assessed the strength of motor unit (MU) short-term synchronization and common fluctuations in mean firing rate (common drive) in the same pairs of MUs in order to evaluate whether these features of voluntary MU discharge arise from a common mechanism. Shared, branched-axon inputs, with the most important being widely divergent monosynaptic projections to motoneurons from motor cortical cells, are regarded as the principal determinants of MU short-term synchronization. It is not known to what extent these synaptic inputs are responsible for common drive behaviour of MUs. MU spike trains from 77 pairs of concurrently active MUs in first dorsal interosseous muscle of 17 subjects were discriminated with the high reliability needed for common drive analysis. For each MU pair, the data used for comparison of the two analyses of correlated MU discharge came from a single trial (1-5 min duration) of isometric abduction of the index finger. Linear regression revealed a weak, significant positive correlation between the strength of MU short-term synchronization and the strength of common drive in the MU pairs (r2 = 0.06, P < 0.05, n = 77), which was slightly stronger when MU pairs with broad synchronous peaks (> 20 ms) were excluded (r2 = 0.09, P < 0.05, n = 63). These data suggest that less than 10% of the variation in the strength of common drive exhibited by pairs of MUs could be accounted for by differences in the strength of MU short-term synchronization. These two phenomena are therefore likely to arise predominantly from separate mechanisms. At least under these task conditions, the widely divergent, branched-axon inputs from single corticospinal neurons which are important in the generation of MU short-term synchronization play only a minor role in the production of common drive of MU discharge rates. PMID- 9367264 TI - Sexual and social experience is associated with different patterns of behavior and neural activation in male prairie voles. AB - Monogamous prairie voles (Microtus ochrogaster) show mating-induced aggression towards conspecific strangers. This behavior is both selective and enduring. The present study was designed to investigate the behavioral conditions for the emergence of selective aggression (by varying prior experience with a female and identity of intruders) and the limbic activation in response to an intruder (by mapping regional staining for c-fos) in male prairie voles. In a first experiment, males that mated with a female for 24 h exhibited aggression towards a male intruder and had more Fos-immunoreactive (Fos-ir) cells in the medial amygdala (AMYGme) and medial preoptic area (MPO) relative to males that cohabited with a female without mating or that had no prior exposure to a female. Cohabited males did not become aggressive. However, these males along with mated males had an increased number of Fos-ir cells in the lateral septum (LS) and the bed nucleus of the stria terminalis (BST) relative to males without prior exposure to a female. In a second experiment, mated males exhibited more offensive aggression to a male intruder but more defensive aggression to a female intruder. Both types of aggression, however, induced an increase in the number of Fos-ir cells in the AMYGme. In addition, Fos-ir staining in the BST was induced selectively in response to a male intruder and a similar trend was found in the LS. Exposure to a male or female intruder did not increase Fos-ir staining in the MPO. Taken together, our data suggest the neural substrates activated by social/sexual activity and involved in response to intruders. The AMYGme was involved in processing intruder-related cues and/or in the regulation of aggressive response to both male and female intruders. The BST and LS were modulated by social experience with a female (mating or cohabitation) and were responsive to male related cues even in the absence of aggression. Finally, the MPO was activated at different magnitudes by social or sexual experience but did not respond to intruder-related cues as measured by Fos-ir. PMID- 9367265 TI - Expression of glutamic acid decarboxylase during human neuronal differentiation: studies using the NTera-2 culture system. AB - Human NTera-2N neurons, but not the parental NTera-2 teratocarcinoma line, decarboxylate [2-(15)N]glutamine to form gamma-[15N]aminobutyric acid (GABA). The reverse transcriptase-polymerase chain reaction (RT-PCR) followed by Southern blotting showed that NTera-2N neurons transcribe the glutamic acid decarboxylase p67 (GAD67) gene, and also demonstrated that there is developmentally regulated alternative splicing of GAD67 mRNA in NTera-2N neurons. As in rat central nervous system (CNS), this mRNA processing generates two RNA transcripts, owing to the inclusion or exclusion of an approximately 80 bp coding region insert. In embryonic day 16 (E16) rat brain, the larger of the two GAD67 mRNAs, which encodes a truncated, inactive apoenzyme, reaches a concentration almost equal to that of the smaller transcript, which encodes functional GAD67. In developing NTera-2N neurons, however, the larger transcript is barely detectable by RT-PCR. RT-PCR also revealed that rat CNS of all ages examined contains GAD65 mRNA, and that GAD65 mRNA is below the detectable range in NTera-2N neurons. PMID- 9367266 TI - Estrogen decreases corpus striatal neurotoxicity in response to 6 hydroxydopamine. AB - Ovariectomized rats treated or not with an estradiol pellet were subjected to an unilateral intrastriatal infusion of 6-hydroxydopamine (6-OHDA). Various parameters of nigrostriatal dopaminergic function as derived from measurements of dopamine and dihydroxyphenylacetic acid (DOPAC) concentrations were determined from the 6-OHDA lesioned and non-lesioned sides of the corpus striatum in these animals. Dopamine concentrations within the 6-OHDA lesioned striatum of estrogen treated rats were significantly greater than non-estrogen-treated rats. There were no differences in striatal dopamine concentrations between estrogen- versus non-estrogen-treated rats on their non-lesioned side. In contrast to that of dopamine, no differences in DOPAC concentrations between estrogen and non estrogen-treated rats were obtained within the 6-OHDA-lesioned side. The DOPAC concentrations on the non-lesioned side of the striatum were significantly greater in the non-estrogen-treated rats. These results demonstrate that estrogen significantly diminishes the depletion of striatal dopamine resulting from the neurotoxin 6-OHDA. The data obtained from the DOPAC determinations imply that this capacity of estrogen may be exerted through actions upon uptake processes of striatal dopaminergic neurons. Such findings suggest that estrogen may function as an important modulatory factor capable of attenuating degeneration within the corpus striatum, and in this way serve as a neuroprotectant of the nigrostriatal dopaminergic system. PMID- 9367267 TI - Induction of metallothionein in astrocytes and microglia in the spinal cord from the myelin-deficient jimpy mouse. AB - Jimpy is a shortened life-span murine mutant whose genetic disorder results in severe pathological alterations in the CNS, including hypomyelination, oligodendrocyte death and strong astroglial and microglial reaction. The knowledge of metallothionein (MT) regulation in the CNS and especially of MT presence in specific glial cell types under pathological conditions is scarce. In the present study, immunocytochemical detection of MT-I + II has been performed in spinal cord sections from 10-12- and 20-22-day-old jimpy and normal animals. The identification of MT-positive glial cells was achieved through double labeling combining MT immunocytochemistry and selective markers for oligodendrocytes, astrocytes and microglia. MT was found in glial cells and was present in the spinal cord of jimpy and normal mice at both ages, but there were remarkable differences in MT expression and in the nature of MT-positive glial cells depending on the type of mouse. The number of MT-positive cells was higher in jimpy than in normal spinal cords. This was apparent in all spinal cord areas, although it was more pronounced in white than in the gray matter and at 20-22 days than at 10-12 days. The mean number of MT-positive glia in the jimpy white matter was 1.9-fold (10-12 days) and 2.4-fold (20-22 days) higher than in the normal one. Astrocytes were the only parenchymal glial cells that were positively identified as MT-producing cells in normal animals. Interestingly, MT in the jimpy spinal cord was localized not only in astrocytes but also in microglial cells. The occurrence of MT induction in relation to reactive astrocytes and microglia, and its role in neuropathological conditions is discussed. PMID- 9367268 TI - Local muscimol disinhibits mesolimbic dopaminergic activity as examined by brain microdialysis and Fos immunohistochemistry. AB - Infusion of muscimol (5 X 10[-5] M, 60 min) into the nucleus accumbens (NAC) through a dialysis membrane caused a significant increase in extracellular dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC). Fos like immunoreactivity induced by intra-NAC infusion of muscimol was seen ipsilaterally in many accumbofugal target areas, but no Fos-positive neurons were seen in the vicinity of the dialysis membrane in the NAC. Sequential staining of Fos and tyrosine hydroxylase (TH) immunoreactivities revealed that a portion of A10 dopaminergic neurons were double-labelled. These results suggest that muscimol in the NAC disinhibits mesolimbic DA neuronal activity possibly through activity of the accumbofugal GABA neuron system. PMID- 9367269 TI - Temperature guardian neurons in the preoptic area of the hypothalamus. AB - Applying the slice method extracellular recordings of 218 hypothalamic neurons in Muscovy ducks during sinusoidal temperature changes were investigated. Seven neurons reacted in a hitherto unknown manner to temperatures very near the physiological limits. Four were exclusively sensitive to temperatures around 36.1 degrees C and three to temperatures around 42.3 degrees C. We recommend to call this kind of neurons temperature guardian neurons. The presented results suggest that the current neuronal model of temperature regulation of vertebrates should be extended by aspects of the two-tier theory of Bligh [J. Bligh, The thermosensitivity of the hypothalamus and thermoregulation in mammals, Biol. Rev. 41 (1966) 317-367]. PMID- 9367270 TI - Neurons in accumbens subterritories of the rat: phasic firing time-locked within seconds of intravenous cocaine self-infusion. AB - Individual neurons were recorded extracellularly in the nucleus accumbens (NAcc) of rats during cocaine self-administration sessions. NAcc neurons exhibited a variety of phasic changes in firing rate within the few seconds before and/or after cocaine self-infusion. Analysis of the topographical distribution of the phasic firing patterns showed that there were no differences between NAcc subterritories in the nature of phasic changes in firing exhibited by neurons in relation to cocaine self-infusion. However, the prevalence of phasic firing was lower in the border regions of the caudal shell and within the caudal shell itself relative to the remainder of the NAcc. PMID- 9367271 TI - Inferior collicular seizure generalization produces site-selective cortical induction of cyclooxygenase 2 (COX-2). AB - Given the potential role of mitogen-inducible cyclooxygenase (COX-2) in CNS damage, patterns of COX-2 induction were determined both before and after seizure generalization from the inferior collicular cortex into the forebrain. With midbrain seizures, no change was found in COX-2-like immunoreactivity, even at the site of seizure genesis. However, upon forebrain seizure generalization, dramatic, ipsilateral increases in COX-2-like immunoreactivity were found in layers II and II of perirhinal, entorhinal and temporal cortex, just dorsal to the perirhinal fissure, coursing from the level of the medial geniculate to the level of the inferior colliculus. No changes in COX-2-like immunoreactivity were found in contralateral cortical regions, retrosplenial cortex, dentate gyrus, subiculum, tenia tectum or inferior colliculus. Thus, initial seizure generalization into the forebrain induces COX-2 expression in a highly specific area of the cerebral cortex. PMID- 9367272 TI - Lumbar but not cervical intrathecal DAMGO suppresses extrasegmental nociception in awake rats. AB - he effect of intrathecally administered [D-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin (DAMGO) on withdrawal latencies evoked by noxious heat applied to either cervical or lumbar dermatomes was studied in awake rats. Administration of DAMGO to the lumbar intrathecal space produces a dose-dependent suppression of withdrawals evoked by noxious thermal stimulation in either lumbar or cervical dermatomes. Administration of the same doses of DAMGO to the cervical spinal cord produces a suppression of withdrawals evoked by stimulation in cervical but not lumbar dermatomes. Control experiments provide evidence that the drugs administered intrathecally to either enlargement do not spread to the other enlargement. PMID- 9367273 TI - Emergence of lung-inflation-related sympathetic nerve activity in spinal cord transected neonatal swine. AB - Sympathetic (SYMP) nerve activity in spinal intact neonatal swine is comprised of prominent bursts reflecting modulation by supraspinal structures involved in shaping central respiratory and baroreceptor activity. After spinal cord transection (SCT), we found no evidence of such modulation. SYMP activity was now related to the ventilatory cycle, exhibiting bursts only during lung inflation. Such activity suggests the emergence of latent spinal circuits which may have the capacity to regulate cardiovascular activity. PMID- 9367274 TI - Cat carotid body chemosensory responses to non-hypoxic stimuli are inhibited by sodium nitroprusside in situ and in vitro. AB - We studied the effects of sodium nitroprusside, a nitric oxide donor, on the chemosensory responses to cyanide and nicotine in the cat carotid body. In situ, sodium nitroprusside infusion reduced the cyanide-evoked responses in a dose dependent manner. In vitro, Tyrode containing nitroprusside reversibly reduced the cyanide- (by 59%) and nicotine-induced (by 45%) chemosensory responses. The present results suggest that chemosensory responses induced by cyanide and nicotine are reduced by increased nitric oxide content, similarly to the hypoxic chemosensory responses. PMID- 9367275 TI - Expression of P-glycoprotein in inner ear capillary endothelial cells of the guinea pig with special reference to blood-inner ear barrier. AB - Expression of P-glycoprotein (P-gp) was detected immunohistochemically in the guinea pig inner ear using mouse anti-P-gp monoclonal antibody C219. P-gp was found only in the capillary endothelial cells of the cochlea and vestibule. The pattern of P-gp immunostaining in the inner ear was similar to that of the brain. The present investigation suggested that P-gp expression in inner ear capillary endothelial cells might play an important role in the blood-inner ear barrier by acting as an extrusion pump. PMID- 9367276 TI - A modified citrulline assay of NOS activity in rat brain homogenates does not detect direct effects of halothane on the kinetics of NOS activity. AB - An improved citrulline radioassay of nitric oxide synthase (NOS) activity was developed to study the direct effects of the volatile anesthetic (VA) halothane on the enzyme kinetics of neuronal NOS derived from different regions of the rat central nervous system (CNS). The Vmax of NOS in both soluble cytosolic and membrane bound particulate fractions varied across regions with greatest activity in the cerebellum and least in the spinal cord. In contrast, the Km was not different across regions or in the cytosolic and particulate fractions. Halothane at 0.5, 1, 2 or 3% delivered concentration had no effect on either kinetic parameter of NOS in any of the regions studied indicating that the VAs have no direct effects on NOS activity. PMID- 9367277 TI - Consistency of nephron filtration measurements by collection of total tubular fluid from different proximal sites. AB - The stability of single nephron glomerular filtration rate (SNGFR) is assured by specific mechanisms such as the tubulo-glomerular feedback system and autoregulation. Studies on renal physiology rely heavily on the measurements of SNGFR, which are feasible only in animals. The measurement of SNGFR by collection of total tubular fluid may be influenced by the fall in intratubular hydrostatic pressure that may reflect the negative pressure applied to the sampling pipette. This effect may become more important with shortening of the distance between the sampling site and the Bowman space. We analysed this putative effect by performing collections of total tubular fluid from the late proximal (LP), and then from the early proximal (EP) segment of the same nephrons. In 128 paired collections LP-SNGFR averaged 35 (SEM 2) nl x min(-1), and was no different from the paired mean EP-SNGFR of 37 (SEM 2) nl x min(-1), P > 0.179. Then EP- and LP- SNGFR were significantly correlated (r = 0.77, P < 0.001). As expected, the respective paired means of absolute and percentage reabsorptions, and those of collection rates were significantly different. The average SNGFR computed from each LP and EP paired measurement was significantly correlated with the simultaneously measured kidney glomerular filtration rate, GFR (r = 0.60, P < 0.0001). The ratio of GFR to SNGFR indicated the expected number of glomeruli. These data would indicate that the sampling site does not influence the measurement of SNGFR in the proximal tubule when the total fluid collection technique is correctly performed. They also exclude a time-dependent activation of the macula densa capable of upregulating SNGFR within the interval elapsing between the beginning of LP and the completion of EP collections, which in our study averaged 4.4 (SEM 0.1) min. PMID- 9367278 TI - Face immersion increases vagal activity as assessed by heart rate variability. AB - We examined whether the diving reflex without breath-holding (face immersion alone) increases vagal activity, as determined by heart rate variability. A group of 15 men [mean age 20 (SD 3) years, height 172 (SD 5) cm, body mass 68 (SD 9) kg] performed 12 trials at various breathing frequencies (5, 10, 15, 20, 30 breaths x min(-1) and uncontrolled breath) with or without face immersion. The R R intervals of the ECG and gas exchange variables were recorded during the 2 min of each trial. The subjects immersed their faces in 8 10 degrees C water while breathing through a short snorkel. The subject sat in the same position either with or without face immersion. The mean R-R interval (RRmean), standard deviations (SD[RR]) and coefficient of variance (CV[RR]) of the R-R interval were calculated from the R-R intervals during 30-120 s. The face immersion significantly increased SD(RR) and CV(RR) (P < 0.05), and increased RRmean (P < 0.05) at 20 breaths x min(-1). Face immersion itself had no effect on oxygen uptake, tidal volume, end-tidal O2 and CO2 partial pressures. The diving reflex without breath-holding increased the heart rate variability, indicating that face immersion alone increases vagal activity. PMID- 9367279 TI - Effects of contract-relax stretching training on muscle performance in athletes. AB - The effects of an 8-week unilateral contract-relax (CR) stretching training program (passive stretch after isometric contraction) on muscular performance were investigated in a group of 16 athletes. The flexibility, maximum torque and angular position as well as contraction work in movements of the knee joint were determined before training and after 4 and 8 weeks of training. The torque measurements were performed under isokinetic conditions, eccentrically at angular velocities of 60 degrees x s(-1) and 120 degrees x s(-1), isometrically at five different joint positions, and concentrically at angular velocities of 60, 120, 180 and 240 degrees x s(-1) using an isokinetic dynamometer. A surface electromyogram (EMG) of the thigh muscles (quadriceps and hamstrings) was recorded simultaneously. As compared to untrained control limbs, significant improvements in active and passive flexibility (up to 6.3 degrees in range of motion), maximum torque (up to 21.6%) and work (up to 12.9%) were observed, and these were especially pronounced under eccentric load conditions. A comparison between integrated EMG recordings during eccentric and concentric loads, as well as the interpretation of the training-induced changes in the EMG, suggest that muscular activity under eccentric loads may be impaired by mental processes. PMID- 9367280 TI - Relationship between isocapnic buffering and maximal aerobic capacity in athletes. AB - This study was performed to clarify the relationship between isocapnic buffering and maximal aerobic capacity (VO2max) in athletes. A group of 15 trained athletes aged 21.1 (SD 2.6) years was studied. Incremental treadmill exercise was performed using a modified version of Bruce's protocol for determination of the anaerobic threshold (AT) and the respiratory compensation point (RC). Ventilatory and gas exchange responses were measured with an aeromonitor and expressed per unit of body mass. Heart rate and ratings of perceived exertion were recorded continuously during exercise. The mean VO2max, oxygen uptake (VO2) at AT and RC were 58.2 (SD 5.8) ml x kg(-1) x min(-1), 28.0 (SD 3.3) ml x kg(-1) x min(-1) and 52.4 (SD 6.7) ml x kg(-1) x min(-1), respectively. The mean values of AT and RC, expressed as percentages of VO2max, were 48.3 (SD 4.2)% and 90.0 (SD 5.2)%, respectively. The mean range of isocapnic buffering defined as VO2 between AT and RC was 24.4 (SD 4.5) ml x kg(-1) x min(-1), and the mean range of hypocapnic hyperventilation (HHV) defined as VO2 between RC and the end of exercise was 5.8 (SD 3.0) ml x kg(-1) x min(-1). The VO2max per unit mass was significantly correlated with AT (r = 0.683, P < 0.01). In addition, VO2max/mass was closely correlated with both the range of isocapnic buffering (r = 0.803, P < 0.001) and RC (r = 0.878, P < 0.001). However, no correlation was found between VO2max per unit mass and the range of HHV (r = 0.011, NS.). These findings would suggest that the prominence of isocapnic buffering, in addition to the anaerobic threshold, may have been related to VO2max of the athletes. The precise mechanisms underlying this proposed relationship remain to be elucidated. PMID- 9367281 TI - Influence of Naloxone on the cellular immune response to head-up tilt in humans. AB - To evaluate a possible role for beta-endorphin in the stress-induced modulation of natural killer (NK) cells, immunologically competent blood cells were followed in eight male volunteers administered either Naloxone or saline (control) during head-up tilt maintained until the appearance of presyncopal symptoms (PS). The PS appeared more rapidly with Naloxone compared to control [5.7 (SEM 1.1) vs 22.3 (SEM 5.1) min; P = 0.01]. The NK cell activity increased threefold during PS partly due to an increase in CD16+ and CD56+ NK cells in blood. In support, NK cell activity boosted with interferon-alpha and interleukin 2 rose in parallel with unboosted NK cell activity and NK cell concentration and activities returned to the baseline level after 105 min. The total lymphocyte count and the concentrations of CD3+, CD4+, CD8+, CD16+, and CD56+ cells increased during PS. Head-up tilt also induced an increase in plasma adrenaline concentration during control PS and a rise in plasma cortisol and adrenocorticotropic hormone concentrations up to 30 min thereafter, whereas no significant changes were found in plasma concentrations of noradrenaline, growth hormone, or beta-endorphin. The results would indicate an influence of endorphin on the increase in plasma adrenaline concentration during head-up tilt and at the same time contra-indicate a significant role for adrenaline in the provocation of PS. The influence of head up tilt on plasma beta-endorphin was too small to influence the modulation of the cellular immune system. PMID- 9367282 TI - Muscle damage induced by running training during recovery from hindlimb suspension: the effect of dantrolene sodium. AB - We examined the extent of morphological alterations and the myosin heavy chain (MHC) distribution in the rat soleus muscle after a 4-week period of spontaneous recovery or retraining after hindlimb suspension (HS). Moreover, we tested the hypothesis that dantrolene sodium, which affects the flux of calcium over the sarcoplasmic reticulum membrane, was able to attenuate muscle damage. Three groups of rats were submitted to 3 weeks of HS, followed by either 4 weeks of unrestricted cage activity (HC, n = 7), or running training for the same period and were compared to age-matched animals (C, n = 8). Trained rats were treated with either placebo or dantrolene sodium (HTP, HTD, n = 8 each, respectively). Four weeks after HS recovery, the percentage of myofibres with internal nuclei (%in) was determined by histological staining with hematoxylin and eosin. %in was affected by the individual rat (P < 0.001), and was higher in the mid-belly region of the muscle (P < 0.05). Muscle damage, as estimated by %in, was more extensive in trained rats (i.e. HTP and HTD) than in HC animals (23% and 12%, respectively). Moreover, dantrolene sodium tended to exert a protective effect on training-induced muscle injury. A 12% increase in type I MHC was observed in both HTP and HTD rats, in comparison with group C animals (P < 0.001). The relative proportion of type-I MHC was inversely correlated with %in (r = -0.65, P < 0.001). Running recovery led to an increased citrate synthase activity in comparison with that of C or HC rats. In conclusion, the present findings demonstrate that running recovery from HS increases the incidence of muscle damage, and that dantrolene sodium administration has only limited protective effects against exercise-induced muscle injury. PMID- 9367283 TI - Physiological effects of variations in spontaneously chosen crank rate during incremental upper-body exercise. AB - The aims of the present study were: first, to assess the interindividual variations of a spontaneously chosen crank rate (SCCR) in relation to the power developed during an incremental upper body exercise on an arm ergometer set at a constant power regime, and second, to compare heart rate (HR) responses, expired minute ventilation (V[E]) and oxygen consumption (VO2) when the pedal rates were chosen spontaneously (T[SCCR]) or set at +/- 10% of the freely chosen rates (T[+10%] and T[-10%], respectively). The mean pedal rate values were linearly related (P < 0.01) with the power developed during arm cranking (r = 0.96), although large variations of pedalling rate strategies were observed between subjects. Maximal power (MP) and time to exhaustion values were significantly higher (P < 0.05) during T(SCCR) than during T(+10%) and T(-10%). Peak VO2 values were significantly higher (P < 0.05) in T(+10%) than in T(SCCR) and T(-10%). The increase in HR, V(E), and VO2 mean values, in relation to the increase in the power developed, was significantly higher (P < 0.05) when the pedal rate was set at plus 10% of the SCCR (T[+/-10%]) than in the two other conditions. The findings of the present study suggest that the use of an electromagnetically braked ergometer, which automatically adjusts the resistance component to maintain a constant work rate, should be used in order to achieve the highest MP values during an incremental upper body exercise. A 10% increase of the SCCR should be used in order to provide the highest peak VO2 value. PMID- 9367284 TI - Motor control and cardiovascular responses during isoelectric contractions of the upper trapezius muscle: evidence for individual adaptation strategies. AB - Ten females (25-50 years of age) performed isometric shoulder flexions, holding the right arm straight and in a horizontal position. The subjects were able to see the rectified surface electromyogram (EMG) from either one of two electrode pairs above the upper trapezius muscle and were instructed to keep its amplitude constant for 15 min while gradually unloading the arm against a support. The EMG electrodes were placed at positions representing a "cranial" and a "caudal" region of the muscle suggested previously to possess different functional properties. During the two contractions, recordings were made of: (1) EMG root mean square-amplitude and zero crossing (ZC) frequency from both electrode pairs on the trapezius as well as from the anterior part of the deltoideus, (2) supportive force, (3) heart rate (HR) and mean arterial blood pressure (MAP), and (4) perceived fatigue. The median responses during the cranial isoelectric contraction were small as compared to those reported previously in the literature: changes in exerted glenohumeral torque and ZC rate of the isoelectric EMG signal of -2.81% x min(-1) (P = 0.003) and 0.03% x min(-1) (P = 0.54), respectively, and increases in HR and MAP of 0.14 beats x min(-2) (P = 0.10) and 0.06 mmHg x min(-1) (P = 0.33), respectively. During the contraction with constant caudal EMG amplitude, the corresponding median responses were -2.51% x min(-1) (torque), 0.01% x min(-1) (ZC rate), 0.31 beats x min(-2) (HR), and 0.93 mmHg x min(-1) (MAP); P = 0.001, 0.69, 0.005, and 0.003, respectively. Considerable deviations from the "isoelectric" target amplitude were common for both contractions. Individuals differed markedly in response, and three distinct subgroups of subjects were identified using cluster analysis. These groups are suggested to represent different motor control scenarios, including differential engagement of subdivisions of the upper trapezius, alternating motor unit recruitment and, in one group, a gradual transition towards a greater involvement of type II motor units. The results indicate that prolonged low-level contractions of the shoulder muscles may in general be accomplished with a moderate metabolic stress, but also that neuromuscular adaptation strategies differ significantly between individuals. These results may help to explain why occupational shoulder-neck loads of long duration cause musculoskeletal disorders in some subjects but not in others. PMID- 9367285 TI - The impact of heat exposure and repeated exercise on circulating stress hormones. AB - To determine if heat exposure alters the hormonal responses to moderate, repeated exercise, 11 healthy male subjects [age = 27.1 (3.0) years; maximal oxygen consumption, VO2max = 47.6 (6.2) ml x kg x min(-1); mean (SD)] were assigned to four different experimental conditions according to a randomized-block design. While in a thermoneutral (23 degrees C) or heated (40 degrees C, 30% relative humidity) climatic chamber, subjects performed either cycle ergometer exercise (two 30-min bouts at approximately 50% VO2max, separated by a 45-min recovery interval, CEx and HEx conditions), or remained seated for 3 h (CS and HS conditions). Blood samples were analyzed for various exercise stress hormones [epinephrine (E), norepinephrine (NE), dopamine, cortisol and human growth hormone (hGH)]. Passive heating did not alter the concentrations of any of these hormones significantly. During both environmental conditions, exercise induced significant (P < 0.001) elevations in plasma E, NE and hGH levels. At 23 degrees C during bout 1: E = 393 (199) pmol x l(-1) (CEx) vs 174 (85) pmol x l(-1) (CS), NE = 4593 (2640) pmol x l(-1) (CEx) vs 1548 (505) pmol x l(-1) (CS), and hGH = 274 (340) pmol x l(-1) (CEx)vs 64 (112) pmol x l(-1) (CS). At 40 degrees C, bout 1: E = 596 (346) pmol x l(-1) (HEx) vs 323 (181) pmol x l(-1) (HS), NE = 7789 (5129) pmol x l(-1) (HEx) vs 1527 (605) pmol x l(-1) (HS), and hGH = 453 (494) pmol x l(-1) (HEx) vs 172 (355) pmol x l(-1) (HS). However, concentrations of plasma cortisol were increased only in response to exercise in the heat [HEx = 364 (168) nmol x l(-1) vs HS = 295 (114) nmol x l(-1)]. Compared to exercise at room temperature, plasma levels of E, NE and cortisol were all higher during exercise in the heat (P < 0.001 in all cases). The repetition of exercise did not significantly alter the pattern of change in cortisol or hGH levels in either environmental condition. However, repetition of exercise in the heat increased circulatory and psychological stress, with significantly (P < 0.001) higher plasma concentrations of E and NE. These results indicate a differential response of the various stress hormones to heat exposure and repeated moderate exercise. PMID- 9367286 TI - Aerobic metabolism and cardioventilatory responses in paraplegic athletes during an incremental wheelchair exercise. AB - The aims of the present study were: (1) to assess aerobic metabolism in paraplegic (P) athletes (spinal lesion level, T4-L3) by means of peak oxygen uptake (VO2peak) and ventilatory threshold (VT), and (2) to determine the nature of exercise limitation in these athletes by means of cardioventilatory responses at peak exercise. Eight P athletes underwent conventional spirographic measurements and then performed an incremental wheelchair exercise on an adapted treadmill. Ventilatory data were collected every minute using an automated metabolic system: ventilation (l x min[-1]), oxygen uptake (VO2, l x min[-1], ml x min[-1] x kg[-1]), carbon dioxide production (VCO2, ml x min[-1]), respiratory exchange ratio, breathing frequency and tidal volume. Heart rate (HR, beats x min[-1]) was collected with the aid of a standard electrocardiogram. VO2peak was determined using conventional criteria. VT was determined by the breakpoint in the VCO2 - VO2 relationship, and is expressed as the absolute VT (VO2, ml x min[ 1] x kg[-1]) and relative VT (percentage of VO2peak). Spirometric values and cardioventilatory responses at rest and at peak exercise allowed the measurement of ventilatory reserve (VR), heart rate reserve (HRr), heart rate response (HRR), and O2 pulse (O2 P). Results showed a VO2peak value of 40.6 (2.5) ml x min(-1) x kg(-1), an absolute VT detected at 23.1 (1.5) ml x min(-1) x kg(-1) VO2 and a relative VT at 56.4 (2.2)% VO2peak. HRr [15.8 (3.2) beats min(-1)], HRR [48.6 (4.3) beat x l(-1)], and O2 P [0.23 (0.02) ml x kg(-1) x beat(-1)] were normal, whereas VR at peak exercise [42.7 (2.4)%] was increased. As wheelchair exercise excluded the use of an able-bodied (AB) control group, we compared our VO2peak and VT results with those for other P subjects and AB controls reported in the literature, and we compared our cardioventilatory responses with those for respiratory and cardiac patients. The low VO2peak values obtained compared with subject values obtained during an arm-crank exercise may be due to a reduced active muscle mass. Absolute VT was somewhat comparable to that of AB subjects, mainly due to the similar muscle mass involved in wheelchair and arm-crank exercise by P and AB subjects, respectively. The increased VR, as reported in patients with chronic heart failure, suggested that P athletes exhibited cardiac limitation at peak exercise, and this contributed to the lower VO2peak measured in these subjects. PMID- 9367287 TI - Proton efflux in human skeletal muscle during recovery from exercise. AB - In recovery from exercise, phosphocreatine resynthesis results in the net generation of protons, while the net efflux of protons restores pH to resting values. Because proton efflux rate declines as pH increases, it appears to have an approximately linear pH-dependence. We set out to examine this in detail using recovery data from human calf muscle. Proton efflux rates were calculated from changes in pH and phosphocreatine concentration, measured by 31P magnetic resonance spectroscopy, after incremental dynamic exercise to exhaustion. Results were collected post hoc into five groups on the basis of end-exercise pH. Proton efflux rates declined approximately exponentially with time. These were rather similar in all groups, even when pH changes were small, so that the apparent rate constant (the ratio of efflux rate to pH change) varied widely. However, all groups showed a consistent pattern of decrease with time; the halftimes of both proton efflux rate and the apparent rate constant were longer at lower pH. At each time-point, proton efflux rates showed a significant pH-dependence [slope 17 (3) mmol x l(-1) x min(-1) x pH unit(-1) at the start of recovery, mean (SEM)], but also a significant intercept at resting pH [16 (3) mmol x l(-1) x min(-1) at the start of recovery]. The intercept and the slope both decreased with time, with halftimes of 0.37 (0.06) and 1.4 (0.4) min, respectively. We conclude that over a wide range of end-exercise pH, net proton efflux during recovery comprises pH-dependent and pH-independent components, both of which decline with time. Comparison with other data in the literature suggests that lactate/proton cotransport can be only a small component of this initial recovery proton efflux. PMID- 9367288 TI - Rest length and compliance of non-immobilised and immobilised rabbit soleus muscle and tendon. AB - The first aim of this study was to measure the contributions of muscle and tendon to the total compliance of resting muscle-tendon units. A second aim was to determine whether the decrease in muscle-tendon unit rest length produced by prolonged immobilisation in a shortened position is mediated primarily by adaptations of the muscle or tendon. One ankle joint from each of five rabbits was immobilised in a plantarflexed position for 14 days. The passive length tension properties of soleus muscle fascicles and tendons from both hindlimbs were measured using a video-based tensile-testing system. In non-immobilised muscles, muscle fascicle strains exceeded tendon strains by up to four times. However, because the rest length of tendon was much greater than that of muscle fascicles, changes in tendon length accounted for nearly half of the total change in muscle-tendon unit length. The rest length of immobilised muscle-tendon units was less than that of non-immobilised muscle-tendon units from contralateral limbs. Most of this difference was attributable to a change in the rest length of the tendon; there was little change in the rest length of muscle fascicles. It is concluded that the tendon is responsible for a large part of the compliance of rabbit soleus muscle-tendon units at physiological resting tensions, and that adaptation of tendon rest length is the primary mechanism by which the rabbit soleus shortens in response to immobilisation at short lengths. PMID- 9367290 TI - Neuroimaging in the evaluation of children and adolescents with intractable epilepsy: II. Neuroimaging and pediatric epilepsy surgery. AB - The costs of epilepsy encompass all aspects of life, including medical, educational, and psychosocial. Adults with intractable epilepsy who undergo epilepsy surgery and have seizure-free outcomes still have significant barriers in the attainment of improved quality of life. For this reason, there is increasing interest in the recognition of children and adolescents with intractable epilepsy who might be epilepsy surgery candidates. This is Part II of an article on the role of neuroimaging in the evaluation of children and adolescents with intractable epilepsy. Part I addressed the role of MRI in detecting the substrates of epilepsy (Pediatr Neurol 1997;17: 19-26); Part II elaborates on the selection process of pediatric patients who might benefit from epilepsy surgery. Although EEG remains the cornerstone of the evaluation process, MRI, SPECT, and PET can play a pivotal role in the identification of the underlying epileptogenic focus and minimize the need for invasive EEG monitoring. Magnetic resonance spectroscopy and magnetoencephalography are also innovative, noninvasive techniques which may aid in the localization of the epileptogenic focus. Functional MRI scans may soon replace invasive technologies in the identification of eloquent cortex that should not be a part of the surgical resection. PMID- 9367289 TI - Hypoxemia increases serum interleukin-6 in humans. AB - Serum concentrations of interleukin (IL) 1 beta, IL-1 receptor antagonist (IL 1ra), IL-6, tumor necrosis factor (TNF) alpha, and C-reactive protein (CRP) were determined in ten healthy men at sea level and during four days of altitude hypoxia (4350m above sea level). The mean (SD) arterial blood oxygen saturations were 78.6 (7.3)%, 82.4 (4.9)%, and 83.4 (5.3)% in the first, second, and third days at altitude, respectively. A symptom score of acute mountain sickness (AMS) revealed that the subjects had mostly light symptoms of AMS. Mean serum IL-6 increased from 1.36 (1.04) pg x ml(-1) at sea level to 3.10 (1.65), 4.71 (2.81), and 3,54 (2.17) pg x ml(-1) during the first three days at altitude, and to 9.96 (8.90) pg x ml(-1) on the fourth day at altitude (ANOVA p = 0.002). No changes occurred in serum concentrations of IL-1 beta, IL-1ra, TNF alpha, or CRP. The serum IL-6 were related to SaO2, (r = -0.45, p = 0.003), but not to heart rates or AMS scores. In conclusion, human serum concentrations of IL-6 increased during altitude hypoxia whereas the other proinflammatory cytokines remained unchanged. The major role of IL-6 during altitude hypoxia seem not to be mediation of inflammation, instead, the role of IL-6 could be to stimulate the erythropoiesis at altitude. PMID- 9367291 TI - Duplication of proteolipid protein gene: a possible major cause of Pelizaeus Merzbacher disease. AB - The classic form of Pelizaeus-Merzbacher disease is a rare X-linked dysmyelinating disorder of the central nervous system in which mutations of the proteolipid protein gene have been reported since 1989. However, mutations in the proteolipid protein gene have been identified in only 10 to 25% of all cases of Pelizaeus-Merzbacher disease, which suggests that other genetic aberrations may be present. Recently, proteolipid protein gene overdosage was discovered to cause Pelizaeus-Merzbacher disease. By using comparative multiplex polymerase chain reaction and restriction fragment length polymorphism analysis, we confirmed the proteolipid protein gene duplication as the cause of Pelizaeus-Merzbacher disease in 4 patients from 3 Chinese families with Pelizaeus-Merzbacher disease with no detectable exonic mutations. These results support the hypothesis that proteolipid protein gene duplication may be a major cause of Pelizaeus-Merzbacher disease in all ethnic groups and also suggest that the molecular diagnosis of Pelizaeus-Merzbacher disease should therefore include duplication analysis of proteolipid protein gene. PMID- 9367292 TI - Acupuncture and the opioid system: implications in management of migraine. AB - We investigated the effectiveness of acupuncture in childhood migraine in 22 children with migraine, randomly divided into two groups: a true acupuncture group (12 children) and a placebo acupuncture group (10 children). Ten healthy children served as a control group. Opioid activity in blood plasma was assayed by two methods: (1) determination of total (panopioid) activity with an opiate radioreceptor assay, and (2) determination of beta-endorphinlike immunoreactivity by radioimmunoassay. The true acupuncture treatment led to significant clinical reduction in both migraine frequency and intensity. At the beginning of the study, significantly greater panopioid activity was evident in plasma of the control group than in plasma of the migraine group. The true acupuncture group showed a gradual increase in the panopioid activity in plasma, which correlated with the clinical improvement. After the tenth treatment, the values of opioid activity of the true acupuncture group were similar to those of the control group, whereas the plasma of the placebo acupuncture group exhibited insignificant changes in plasma panopioid activity. In addition, a significant increase in beta-endorphin levels was observed in the migraine patients who were treated in the true acupuncture group as compared with the values before treatment or with the values of the placebo acupuncture group. The results suggest that acupuncture may be an effective treatment in children with migraine headaches and that it leads to an increase in activity of the opioidergic system. PMID- 9367293 TI - Developmental immunohistochemistry of growth inhibitory factor in normal brains and brains of patients with Down syndrome. AB - Growth inhibitory factor, a new metallothioneinlike protein, was investigated at postmortem examination in the brains of 18 patients with Down syndrome ranging in age from 18 weeks gestation to 50 years of age and in 20 age-matched normal controls by developmental immunohistochemistry. In the frontal cortex of both Down syndrome patients and controls, growth inhibitory factor immunoreactivity was localized in the cell bodies and processes of protoplasmic astrocytes from 18 weeks gestation, and these immunoreactive processes formed so dense a meshwork in the gray matter that they outlined neuronal perikarya as negative contours in the brain at age more than 16 years. The number of growth inhibitory factor immunoreactive astrocytes exhibited a greater increase in layer 3 than in layer 2 in controls from 37 weeks gestation to 7 months of age, although there was no difference in the growth inhibitory factor-positive cell number between layers 2 and 3 in young Down syndrome patients. Therefore, growth inhibitory factor in astrocytes may be correlated with dendritic maturation of neurons. On the other hand, growth inhibitory factor-immunoreactive astrocytes in layer 2, where senile plaques are abundant, were smaller than those in layer 3 in adult Down syndrome patients from age 32 years. When senile plaques began to immunoreact with the amyloid precursor protein, the number of growth inhibitory factor-immunoreactive astrocytes decreased around senile plaques in elderly Down syndrome brains with the Alzheimer type of dementia. On the contrary, the number of glial fibrillary acidic protein-immunoreactive astrocytes around senile plaques increased. This loss of growth inhibitory factor around senile plaques may be correlated with neuronal loss or degeneration and lead to sprouting responses which may be involved in the formation of senile plaques. PMID- 9367294 TI - Changes in AMPA glutamate and dopamine D2 receptors in hypoxic-ischemic basal ganglia necrosis. AB - Changes in the AMPA glutamate receptor subunits (GluR1, 2-3, and 4) and dopamine D2 receptor (D2R) were investigated in 16 cases of hypoxic-ischemic basal ganglia necrosis (BGN) by immunohistochemistry. Immunoreactivity to GluR1, 2-3, and 4 was observed in the cytoplasm and dendrites of small and large neurons in the basal ganglia. Neuronal immunoreactivity to GluR1, 2-3, and 4 was decreased in cases with acute BGN as compared with that in age-matched controls, the areas of decreased immunoreactivity corresponding to the damaged regions observed on hematoxylin and eosin staining. Glia in the basal ganglia exhibited immunoreactivity to GluR4 in 4 patients with acute BGN, 3 of the 4 surviving for 12 to 35 days. In addition, neuronal immunoreactivity to D2R was also decreased in cases of acute BGN, the decrease being similar to that of GluR1, 2-3, and 4. Our results suggest that excitotoxicity mediated by GluR1, 2-3, and 4 is involved in the pathogenesis of hypoxic-ischemic neuronal damage, and that GluR4 expressed in glia of the BG in the late stage of hypoxic-ischemic injury may participate in the delayed and long-term response of the glia to injury. The decrease in neuronal D2R may be related to downregulated synthesis of the D2R protein induced by the decrease in GluR1-4 in the basal ganglia. PMID- 9367295 TI - Risk factor of complications requiring neurosurgical intervention in infants with bacterial meningitis. AB - Among 50 consecutive cases of bacterial meningitis in infants aged 6 months or less, 9 (Group I) were confirmed to have complications requiring neurosurgery during the first 2 weeks of antibiotic treatment. Neurosurgery was performed in 40, 33, and 30% of cases caused by Streptococcus pneumoniae, Pseudomonas aeruginosa, and Escherichia coli, respectively. There were 5 cases of subdural empyema, 1 case of brain abscess, 1 case of subdural empyema and brain abscess, and 2 cases of ventriculitis with severe hydrocephalus. All complications requiring neurosurgery were initially detected by cranial ultrasonography. The other 41 patients who did not undergo neurosurgery were classified as Group II. Comparison of clinical presentations and laboratory findings between the two groups showed that Group 1 contained more patients with a history of inadequate treatment, and longer duration of illness before diagnosis. Except for prolonged disturbance of consciousness, there was no difference between the two groups in clinical and laboratory data on admission or in clinical course during therapy. Due to the high incidence of complications requiring neurosurgical treatment, cost-effective cranial ultrasound is recommended for screening every young infant with bacterial meningitis, especially in cases caused by S. pneumoniae. PMID- 9367296 TI - Recurrent seizures in metachromatic leukodystrophy. AB - The unusual presentation of juvenile onset metachromatic leukodystrophy (MLD) and frequent complex partial seizures in a patient led us to perform a retrospective study of 18 patients with MLD to identify the prevalence and type of recurrent seizures during the first 2 years of the disease. Five of 17 patients (29%) had developed recurrent seizures within 12 months of the onset of symptoms, and one patient was lost to follow-up. By 24 months after onset of symptoms, 5 patients were lost to follow-up, and 6 of the remaining 13 patients (46%) had developed recurrent seizures. In all, 7 patients, 4 with late infantile-onset and 3 with juvenile-onset disease, developed recurrent seizures. Four patients, including 3 with juvenile-onset disease had complex partial seizures. We conclude that recurrent seizures are common in MLD and may occur at any stage of the disease, particularly in patients with juvenile onset. Generalized seizures are more frequent in patients with late infantile-onset, whereas partial seizures are more common in those with juvenile-onset disease. PMID- 9367297 TI - Guanidinoacetate methyltransferase deficiency: new clinical features. AB - Guanidinoacetate methyltransferase deficiency is a recently described inborn error of creatine biosynthesis that responds to treatment with oral creatine supplementation. The previously reported clinical features consist of developmental arrest and an extrapyramidal movement disorder. We describe a patient who presented with epilepsy, global developmental delay, and a persistently low plasma creatinine level. The diagnosis was established by measuring urinary guanidinoacetate and by demonstrating absence of the creatine/phosphocreatine peak in the patient's basal ganglia in 1H magnetic resonance spectroscopy. The clinical and biochemical abnormalities responded to creatine replacement. PMID- 9367298 TI - Extra and central pontine myelinolysis in a child with adrenal insufficiency. AB - We report a 5-year-old patient with adrenal insufficiency (AI) who had a subacute monophasic neurologic illness and brainstem and striatal lesions on brain imaging. The prominent electrolyte abnormalities in AI indicate that extra and central pontine myelinolysis is the likely cause. An association between AI and extra pontine myelinolysis has not previously been reported in children. PMID- 9367299 TI - Mitochondrial encephalomyopathy with 15915 mutation: clinical report. AB - A 16-year-old boy with mitochondrial encephalomyopathy had seizures, short stature, muscle weakness, progressive hearing loss, mental retardation, and myoclonus. His cranial computed tomography showed progressive calcification in the basal ganglia and cerebral atrophy. Muscle biopsy revealed many ragged-red fibers with variable cytochrome c oxidase activity and some strongly succinate dehydrogenase-reactive blood vessels. Sequence analysis of the entire mitochondrial DNA revealed a novel point mutation in the tRNA-Thr gene at nucleotide pair 15915. Serum lactate levels were decreased by high-dose coenzyme Q10 (CoQ10) therapy. The spectral power density, a parameter of background activity on electroencephalography, was markedly improved after additional administration of idebenone. After initiation of combined CoQ10 and idebenone therapy, the clinical abnormalities did not progress for 16 months. PMID- 9367300 TI - Syndrome of encephalopathy, petechiae, and ethylmalonic aciduria. AB - We report a boy 20 months of age with encephalopathy, petechiae, and ethylmalonic aciduria (EPEMA). Other clinical features were severe hypotonia, orthostatic acrocyanosis, and chronic diarrhea. Magnetic resonance imaging (MRI) of the brain demonstrated bilateral lesions in the lenticular and caudate nuclei, periaqueductal region, subcortical areas, white matter, and brainstem. Short and medium chain Acyl-CoA dehydrogenase and cytochrome c oxidase (COX) activities in fibroblasts were normal. Muscle histochemistry disclosed diffuse COX deficiency, and respiratory chain activities in muscle disclosed severe COX deficiency. Twelve other patients with similar clinical features have been reported. Muscle COX activity, studied only in four, demonstrated a clear-cut defect. PMID- 9367301 TI - Moyamoya disease and protein S deficiency: a case report. AB - A 2-year-old child who acutely developed hemiplegia and seizure was found to have moyamoya disease and heterozygous protein S deficiency. This case report should alert physicians to the possible coexistence of moyamoya disease and protein S deficiency, even in the case of typical moyamoya disease. The intimate relationship between the two require further study. PMID- 9367302 TI - Benign congenital hemifacial spasm. AB - Hemifacial spasm (HFS) is characterized by involuntary, irregular contraction of the muscles innervated by one facial nerve. Usually, it is caused by facial nerve injury either due to microvascular compression or a posterior fossa tumor, but it also occurs without apparent cause. It is rare in children; no congenital cases have yet been reported. We report the first case of congenital HFS in a term newborn delivered by forceps after a normal labor. Multimodal evoked potentials, electroencephalogram, computed tomography of the petrous bone, as well as brain magnetic resonance imaging and angiography disclosed no abnormalities. Serial neurodevelopmental examinations and video recordings performed until 8 months of age documented a normal neurodevelopmental status and a tendency for spontaneous diminution of the HFS. An intrauterine facial nerve injury as the causative factor of HFS, being responsible for its benign course, is proposed. PMID- 9367303 TI - Rolandic epilepsy and cortical dysplasia: MRI correlation of epileptiform discharges. AB - An 8 year-old girl presented with simple facial motor seizures. Although the electroencephalogram (EEG) demonstrated left hemisphere centrotemporal spikes with features consistent with benign rolandic epilepsy, magnetic resonance imaging (MRI) indicated a left hemisphere focal cortical dysplasia. MRI-assisted EEG dipole analysis of the spikes suggested that the rolandic fissure rather than the focal cortical dysplasia was the origin of the epileptic spike discharge. This noninvasive method may be a useful adjunct in evaluation of some patients with epilepsy and focal superficial cerebral lesions. PMID- 9367304 TI - Hypomelanosis of Ito associated with hemimegalencephaly: a clinicopathological study. AB - A girl with hypomelanosis of Ito was studied both clinically and at postmortem examination. She manifested severe epilepsy early after birth. Magnetic resonance imaging demonstrated left-sided hemimegalencephaly. The seizures were secondarily generalized or unilateral initially, followed by infantile spasms with asymmetrical hypsarrhythmia at 1.5 months of age. Frequent complex partial seizures, refractory to anti-epileptic drug treatments appeared at 4 months of age. She died of pneumonia at the age of 14 months. Postmortem examination revealed marked asymmetry of the cerebrum and gyral abnormalities in the left cerebral hemisphere. Histopathologically, severe disorganization of the neuronal cytoarchitecture was evident. Absence of delineation between cortical gray and white matter was evident, as was increase and hypertrophy of the neurons and glial cells. We believe that the association of skin and brain lesions was not one of chance; that is, they may share a common pathogenetic mechanism. PMID- 9367305 TI - Reversible MRI lesions due to pegaspargase treatment of non-Hodgkin's lymphoma. AB - L-Asparaginase is the major induction-phase agent for treatment of acute lymphoblastic leukemia (ALL) and an important adjuvant in treatment of non Hodgkin's lymphoma (NHL). However, L-asparaginase-induced disturbances of clotting homeostasis may result in thrombosis or hemorrhage. Thrombotic occlusion of small cerebral veins has been reported in patients with ALL treated with this agent, but have not been described in NHL patients or those treated with the long acting synthetic congener, pegaspargase. We report a 16-year-old boy with NHL who developed a focal motor seizure 15 min after receiving intravenous pegaspargase. MRI of the brain demonstrated multiple cortical and subcortical lesions that most likely represented focal brain edema due to thrombotic venous occlusion, which improved remarkably within 3 days and completely resolved within 3 weeks without specific intervention or permanent clinical consequences. This process must be considered when such changes are detected in NHL patients. PMID- 9367306 TI - Comparison of T2-weighted and fluid-attenuated inversion-recovery fast spin-echo MR sequences in intracerebral AIDS-associated disease. AB - PURPOSE: To compare the value of fast fluid-attenuated inversion-recovery (FLAIR) with T2-weighted fast spin-echo MR imaging in the detection of acquired immunodeficiency virus (AIDS)-related lesions of the brain. METHODS: Forty-four human immunodeficiency virus (HIV)-positive patients were examined with both sequences on either a 1.0-T or a 1.5-T MR system. The number, size, location, and conspicuity of the lesions were evaluated by two independent observers. Contrast ratios between lesions and normal brain/cerebrospinal fluid were determined, and contrast-to-noise ratios were calculated. RESULTS: FLAIR was found to be superior to T2-weighted fast spin-echo in detection of small lesions and of lesions located in cortical/subcortical regions and deep white matter. The two techniques were equal in delineation of lesions larger than 2 cm and for lesions located in the basal ganglia and posterior fossa. In 24 patients, more lesions were detected with the FLAIR fast spin-echo technique. Lesion/cerebrospinal fluid contrast ratios and contrast-to-noise ratios were significantly higher for the FLAIR fast spin-echo sequences than for the T2-weighted fast spin-echo sequences. CONCLUSION: FLAIR allows early detection of small lesions in subcortical and cortical locations, especially in HIV encephalitis. Because of its improved lesion detection rate and greater overall lesion conspicuity, we believe FLAIR is useful in the evaluation of subtle changes in the brains of AIDS patients with central nervous system disease, and could even replace the T2-weighted fast spin echo technique. PMID- 9367307 TI - Fluid-attenuated inversion-recovery fast spin-echo MR: a clinically useful tool in the evaluation of neurologically symptomatic HIV-positive patients. PMID- 9367308 TI - Comparison of spin-echo MR pulse sequences for imaging of the brain. AB - PURPOSE: To determine the value of the gradient- and spin-echo (GRASE) technique as compared with the fast spin-echo and conventional spin-echo techniques in MR imaging of the brain. METHODS: Sixty-six patients with ischemic and neoplastic brain lesions were examined with T2-weighted spin-echo, fast spin-echo, and GRASE sequences. Three independent observers evaluated the contrast characteristics of anatomic and pathologic structures and of artifacts. Quantitative image analysis included region-of-interest measurements of anatomic structures and lesions. RESULTS: The contrast of anatomic structures was superior in images obtained with conventional and fast spin-echo techniques as compared with those obtained with the GRASE technique. Extended lesions, such as tumors and territorial infarcts, were identified equally with all techniques. For delineation of small ischemic lesions, GRASE was slightly inferior to fast and conventional spin-echo sequences. Flow artifacts were considerably reduced with fast spin-echo and GRASE sequences. Chemical-shift artifacts were significantly reduced, but ringing artifacts were more pronounced with GRASE. CONCLUSION: Fast spin-echo remains the standard technique in MR imaging of the brain. However, GRASE might be useful in special cases, such as with uncooperative patients whose conventional or fast spin-echo images show severe motion artifacts. PMID- 9367309 TI - Fast inversion-recovery MR: the effect of hybrid RARE readout on the null points of fat and cerebrospinal fluid. AB - PURPOSE: To evaluate the effect of the hybrid RARE (rapid acquisition with relaxation enhancement) readout, commonly coupled to inversion-recovery pulse sequences, on the null inversiton time (TI) of fluid and fat using both phantoms and human volunteers. METHODS: Two phantoms, simulating fat (phantom A) and cerebrospinal fluid (phantom B), respectively, were imaged using a fast inversion recovery sequence that coupled an inversion-recovery preparation pulse to a hybrid RARE readout. At repetition times (TRs) ranging from 700 to 20,000, the TI necessary to null the signal from each phantom (null TI) was determined for an echo train length of 4, 6, 8, 10, 12, 14, 16, 18, and 20, respectively. Plots of null TI versus echo train length at different TRs were generated for both phantoms. Fast inversion-recovery MR imaging of the cervical spine and brain was performed in healthy volunteers. At a fixed TR and TI, the adequacy of signal suppression from bone marrow and cerebrospinal fluid was assessed as a function of echo train length. RESULTS: There was a gradual decrease of null TI for both phantoms with echo train length. This decrease persisted at longer TRs for phantom B (T1 = 3175 +/- 70 milliseconds) than for phantom A (T1 = 218 +/- 5 milliseconds). In the human volunteers, there was a gradual loss of suppression of signal from bone marrow and cerebrospinal fluid, with changes in the hybrid RARE readout. CONCLUSION: To optimize specific tissue suppression, radiologists implementing fast inversion-recovery MR imaging should be aware of the effects of the hybrid RARE readout on null TI. PMID- 9367310 TI - Half-fourier acquisition single-shot turbo spin-echo (HASTE) MR: comparison with fast spin-echo MR in diseases of the brain. AB - PURPOSE: To compare an ultrafast T2-weighted (half-Fourier acquisition single shot turbo spin-echo [HASTE]) pulse sequence with fast spin-echo T2-weighted sequences in MR imaging of brain lesions. METHODS: Fast spin-echo and HASTE images of 34 consecutive patients over the age of 50 years or with suspected demyelinating disease were reviewed independently by two neuroradiologists for the number of lesions less than 5 mm and greater than or equal to 5 mm, and for lesion conspicuity, gray-white matter differentiation, and extent of periventricular confluent signal abnormality. The reviewers also assessed for the presence of hemosiderin and extent of motion artifacts. RESULTS: Per patient, the mean number of 5-mm or larger lesions detected on fast spin-echo images (1.4) relative to the number detected on HASTE images (0.8) was not statistically significant. For lesions less than 5 mm, fast spin-echo images showed more lesions (7.5) than HASTE images did (2.4). The fast spin-echo images were better at depicting gray-white matter differentiation, conspicuity of lesions, and periventricular signal abnormality. Of four T2 hypointense lesions seen on fast spin-echo images, none was detected on HASTE images. CONCLUSION: Although the HASTE technique might be useful for rapid imaging of the brain, our study shows a diminished sensitivity for the detection of lesions less than 5 mm in diameter and for T2 hypointense lesions. PMID- 9367311 TI - A pain in the ear: the radiology of otalgia. PMID- 9367312 TI - A practical approach to the treatment of vasospasm. PMID- 9367313 TI - Intracranial angioplasty: experience and complications. AB - PURPOSE: To review our experience with intracranial angioplasty, including the complications we encountered. METHODS: During a 3-year period, from 1993 to 1996, 10 patients had intracranial percutaneous transluminal angioplasty (PTA). The stenosed vessels included three internal carotid arteries, one middle cerebral artery, one basilar artery, and five vertebral arteries. Stenosis in all patients was 75%, or greater. PTA was technically successful in eight patients; in two patients it could not be performed owing to inability to traverse the stenosed area. RESULTS: Two patients had successful and uneventful PTA. Five patients had vasospasm, which resolved with local vasodilators in two and with repeat PTA in one. Vasospasm led to stroke in two patients. Compromise of perforating vessels and arterial dissection were associated with stroke in two patients. CONCLUSION: Intracranial PTA is technically feasible but associated with risks related to vasospasm, arterial trauma, and compromise of perforating vessels. PMID- 9367314 TI - Endovascular electrocoagulation: concept, technique, and experimental results. AB - PURPOSE: To evaluate the safety and efficacy of an embolotherapeutic technique that uses electrolytically detachable platinum coils and radio frequency (RF) energy to achieve rapid and distal occlusion of targeted vessels. METHODS: In swine, branches of the ascending cervical artery and the hepatic artery measuring 1.5 mm or less were subjected to endovascular electrocoagulation. RF energy was delivered through modified Guglielmi detachable platinum coils that were placed in the targeted arteries. Ohmic heating generated by RF caused vessel occlusion. After the vessel occlusions were confirmed angiographically, the platinum microcoils were electrolytically detached from the delivery wire and left in the vessels as implants. RESULTS: All vessels were rapidly and superselectively occluded by endovascular electrocoagulation. Following use of the appropriate methods derived from this research, we did not observe rupture of the artery, dissection of the artery, unintended occlusion, or migration of the platinum microcoil. Histologic examination of treated vessels at 6 and 12 weeks revealed obliteration of the vessel lumen by the platinum microcoil surrounded by granulation tissue. CONCLUSION: Endovascular electrocoagulation is a rapid method of achieving vessel occlusion. It may be a useful and controllable embolotherapeutic technique when expeditious occlusion of small vessels and distal superselectivity are desired. PMID- 9367316 TI - A case in favor of aneurysmographic studies: a perforating artery originating from the dome of a basilar tip aneurysm. AB - A posterior perforating artery originating from the dome of a basilar tip aneurysm is reported. The exact origin of this perforator was identified by selective aneurysmography only. This observation provides an argument favoring the consideration of aneurysmographic studies before treatment of large aneurysms located in proximity to areas of normal perforating arteries. PMID- 9367315 TI - Arteriovenous shunt measurement during endovascular therapy for cerebrospinal lesions. AB - PURPOSE: To determine (a) whether superselective angioscintigraphy with technetium-99m macroaggregated albumin (99mTc-MAA) can be used for the evaluation of arteriovenous shunting in tumors and vascular malformations of the head and spine and (b) whether the amount of microparticles shunted is related to diagnosis, lesion size, or angiographic pattern. METHODS: Particles of 99mTc-MAA with a calibrated diameter of 25 to 50 microm were delivered intraarterially in feeders of head and spine tumors and vascular malformations in 38 patients. The first estimation of the proportion of particles reaching the lungs was made on line in the angiography suite using a hand-held lead-shielded detector. Evaluation of the intralesional shunt (pulmonary shunt index, or PSI) was derived from quantitative gamma camera recordings of tumoral and pulmonary activity after the embolization procedure was complete. RESULTS: The PSI value ranged from 48% to 100% for vascular malformations and vascular tumors (n = 11), 82% to 95% for juvenile angiofibromas (n = 4), 63% to 70% for high-grade gliomas (n = 2), 0% to 50% for renal cell carcinoma metastases (n = 4), 0% to 86% for meningiomas (n = 11), and 0% to 36% for paragangliomas (n = 6). Angiographically, the presence of visible arteriovenous channels was predictive of a high PSI. In contrast, the presence of early venous drainage was associated with a wide PSI range. CONCLUSION: Superselective 99mTc-MAA angioscintigraphy of tumors and vascular malformations of the head and spine is a valuable method for quantifying an intralesional arteriovenous shunt before embolization. PMID- 9367318 TI - The use of hyperventilation in contrast-enhanced MR of brain tumors. AB - Angiographic studies have demonstrated improved visibility of glial tumors after hyperventilation. The present study was undertaken to determine whether hyperventilation would change the MR enhancement characteristics of various glial tumors. Eighteen patients were studied twice: once with standard contrast enhanced MR imaging and again with standard imaging plus hyperventilation. After hyperventilation, six low-grade astrocytomas showed no change and three showed a small decrease in relative enhancement (<10%). The ependymomas showed a 10% to 13% increase in the degree of enhancement, but no change in the area of enhancement. All the anaplastic astrocytomas showed an increase in the degree of enhancement (mean, 38%). Three of the anaplastic astrocytomas showed new foci of enhancement that were not seen on the nonhyperventilation study. Hyperventilation appears to be an inexpensive and safe method for increasing the conspicuity of abnormal areas of the blood-brain barrier. PMID- 9367317 TI - Accuracy of single-voxel proton MR spectroscopy in distinguishing neoplastic from nonneoplastic brain lesions. AB - PURPOSE: To measure the accuracy of single-voxel, image-guided proton MR spectroscopy in distinguishing normal from abnormal brain tissue and neoplastic from nonneoplastic brain disease. METHODS: MR spectroscopy was performed at 0.5 T with the point-resolved spectroscopic pulse sequence and conventional postprocessing techniques. Subjects consisted of a consecutive series of patients with suspected brain neoplasms or recurrent neoplasia and 10 healthy adult volunteers. Fifty-five lesions in 53 patients with subsequently verified final diagnoses were included. Spectra were interpreted qualitatively by visual inspection by nonblinded readers (prospectively) with the benefit of prior clinical data and imaging studies, and by blinded readers (retrospectively). The nonblinded readers interpreted the spectra as diagnostic or not, and, if diagnostic, as neoplastic or nonneoplastic. The blinded readers classified the spectra as diagnostic or not, and, if diagnostic, as normal or abnormal and as neoplastic or nonneoplastic (when abnormal). The sensitivity, specificity, positive and negative predictive values, and accuracy were calculated from blinded and nonblinded MR spectroscopy interpretations. A receiver operator characteristic (ROC) curve analysis was performed on blinded MR spectroscopy interpretations. RESULTS: The diagnostic accuracy averaged across four blinded readers in differentiating patients from control subjects was .96, while the area under the aggregate (pooled interpretations) ROC curve approached unity. Accuracy in the nonblinded and blinded discrimination of neoplastic from nonneoplastic disease was .96 and .83, respectively. The area under the aggregate ROC curve in the blinded discrimination of neoplasm from nonneoplasm was .89. CONCLUSIONS: Image-guided proton spectra obtained at 0.5 T from patients with suspected neoplasia can be distinguished from spectra in healthy control subjects, and neoplastic spectra can be distinguished from nonneoplastic spectra with a high degree of diagnostic accuracy. PMID- 9367319 TI - Extensive cerebrospinal fluid enhancement with gadopentetate dimeglumine in a primitive neuroectodermal tumor. AB - We report a case of diffuse enhancement of the cerebrospinal fluid (CSF) after intravenous administration of gadopentetate dimeglumine in an 8-year-old girl with a primitive neuroectodermal tumor. The enhancement of the CSF was caused by leakage of gadolinium chelate complexes into the CSF, which was proved by CSF analysis. PMID- 9367320 TI - MR contrast enhancement of the normal neonatal brain. AB - PURPOSE: To determine the pattern of enhancement on contrast-enhanced MR studies of the brain in neonates. METHODS: Contrast-enhanced brain MR studies of 16 neonates were reviewed retrospectively. All infants had normal neonatal courses, normal noncontrast MR findings, and normal neurologic examinations at age 12 months. All enhancing regions within the brain, dura, calvaria, and orbits were recorded. An enhancement factor, F = (Ic-Ip)/Ip, was calculated from region-of interest intensity measurements in five regions of each hemisphere (basal ganglia, thalami, and three hemispheric locations), where Ic was signal intensity after contrast administration and Ip was the noncontrast signal intensity for each region. RESULTS: Enhancement was detected in the choroid plexus, pituitary infundibula, pineal glands, dura, veins and venous sinuses, cranial sutures, and irises of the orbital globes. No enhancement of the brain parenchyma was detected by visual inspection, although some change in signal intensity of the cerebral parenchyma was detected by the region-of-interest intensity measurements, with enhancement factors ranging from 0 to 0.08 (mean, 0.04). No consistent regional variation in enhancement was detected. Because the degree of enhancement was identical to that in the normal adult brain, the slight enhancement detected was attributed to contrast material in capillaries and small venules. CONCLUSION: In addition to the expected findings of enhancement of the pituitary stalk, the pineal gland, the choroid plexus, the dura, and the cerebral veins, we detected enhancement of the calvarial sutures and ocular irises. No evidence of enhancement of the cerebral parenchyma was detected, suggesting that the blood brain barrier to gadolinium chelates is intact in the neonatal brain. PMID- 9367321 TI - Duplicated odontoid process: plain radiographic and CT appearance of a rare congenital anomaly of the cervical spine. AB - We describe a duplication of the odontoid process in a 6-year-old patient that included a partially fused midline ossicle on the anterior arch of C-1, fusion of the anterior lip of the foramen magnum and the arch of C-1, and an incomplete bony posterior arch of C-1. PMID- 9367322 TI - Adenoidal width and HIV factors. AB - PURPOSE: To determine the factors that correspond to adenoidal hypertrophy, often prominent in human immunodeficiency virus (HIV)-positive patients. METHODS: The sagittal T1-weighted MR images of 21 HIV-positive patients (age range, 25 to 50 years; mean, 37 years) and 21 healthy control subjects (age range, 24 to 55 years; mean, 35 years) were reviewed blindly and independently by two radiologists who measured the maximal dimension of the nasopharyngeal lymphoid tissue. Twenty-six additional HIV-positive patients were combined with the original 21 HIV-positive patients, and the hematologic studies of these 47 patients were compared with the adenoidal measurements to assess whether a relationship existed between nasopharyngeal prominence and hematocrit, white blood cell count, and CD4 count. RESULTS: Mean adenoidal width was 6.76 mm (SD, 5.82) in the HIV-positive population, but was only 3.36 mm (SD, 2.48) in the age matched control group. Age and HIV status correlated with nasopharyngeal width measurements. No relationship between adenoidal width and hematocrit, CD4 count, or white blood cell count was evident. CONCLUSION: After correcting for age, we found that adenoidal lymphoid tissue is more abundant in HIV-positive persons than in control subjects. The hematologic ramifications of this finding remain uncertain. PMID- 9367323 TI - Solitary subglottic neurofibroma: MR findings. AB - We present a case of subglottic neurofibroma, which is of interest because laryngeal neurofibroma rarely occurs in the subglottic space. Nonspecific MR findings did not allow us to exclude the preoperative diagnosis of hemangioma. PMID- 9367324 TI - Kikuchi disease: CT and MR findings. AB - Two cases of Kikuchi disease showed variable nodal enhancing features, including homogeneous enhancement and focal or extensive nodal necrosis on contrast enhanced CT scans. At MR imaging, the area of central necrosis was isointense or hypointense on T1-weighted images and had a lower signal than nonnecrotic areas on T2-weighted images. The CT appearance of Kikuchi disease can be variable and can mimic not only lymphoma but various nodal diseases with nodal necrosis, including metastasis and tuberculosis. PMID- 9367326 TI - MR findings in hereditary isolated growth hormone deficiency. AB - PURPOSE: To describe the MR characteristics by which patients with hereditary isolated growth hormone deficiency (GHD) can be distinguished from patients with other types of GHD. METHODS: A total of 51 patients with GHD were examined prospectively with MR imaging. On the basis of familial occurrence of GHD and genetic analysis, 10 patients met the criteria for hereditary deficiency. In each case, the height of the pituitary gland, the presence and location of the posterior neurohypophysis, and the completeness of the stalk were recorded. The findings in the hereditary group were compared with those in the rest of the patients. RESULTS: In all 10 patients with hereditary GHD, the adenohypophysis, the neurohypophysis, and the stalk were normal. Of the other 41 patients, the height of the gland was normal in three (7%), the neurohypophysis was abnormal in all, and the stalk was truncated in all but two patients (95%). CONCLUSIONS: The subgroup of patients with hereditary GHD exhibited an anatomically normal pituitary-hypothalamic region. This is in contrast to the majority of patients with idiopathic GHD. MR imaging can contribute to the classification of patients with GHD. PMID- 9367325 TI - Three-dimensional MR myelography of traumatic injuries of the brachial plexus. AB - PURPOSE: To determine the diagnostic accuracy of three-dimensional MR myelography in the evaluation of traumatic injuries of the brachial plexus. METHODS: Twenty patients with clinical and electromyographic evidence of traumatic brachial plexopathy were examined with three-dimensional MR myelography, conventional cervical myelography, and CT myelography 1 to 9 months after trauma. Three dimensional MR myelography was performed on a 1.5-T MR unit with a constructive interference in steady state (CISS) technique. For each patient, maximum intensity myelographic projections and multiplanar reconstruction reformatted 1 mm axial sections were obtained from the same 3-D data set. Three-dimensional MR myelographic findings were compared with findings at cervical myelography and CT myelography. Surgical findings were available for comparison in 13 patients. RESULTS: Three-dimensional MR myelography enabled detection of meningoceles with avulsed or intact nerve roots, partial or complete radicular avulsions without disruption of the thecal sac, dural sleeve abnormalities, and dural scars. Assuming cervical myelography and CT myelography as the standards of reference, 3 D MR myelography showed 89% sensitivity, 95% specificity, and 92% diagnostic accuracy in the evaluation of nerve root integrity. CONCLUSION: Three-dimensional MR myelography can show the majority of traumatic lesions that involve the proximal portion of the brachial plexus in a single rapid examination. On the basis of our findings, we propose this technique as a screening examination for patients with traumatic brachial plexus palsy. PMID- 9367327 TI - Persistent high MR signal of the posterior pituitary gland in central diabetes insipidus. AB - We describe three cases of central diabetes insipidus, each with a different pathogenesis, in which unexpected hyperintensity of the posterior pituitary gland was seen on T1-weighted MR images obtained at the time of presentation. In the first case (idiopathic), the posterior pituitary signal persisted more than 10 years; in the second case (Langerhans cell histiocytosis), the signal disappeared within 3 months, despite early specific chemotherapy with etoposide; and in the third case (transient), the posterior signal disappeared within 1 year, but it was documented at the time of spontaneous reversal of polyuria and polydipsia. PMID- 9367328 TI - Proton MR spectroscopy of delayed cerebral radiation in monkeys and humans after brachytherapy. AB - PURPOSE: To determine whether radiation necrosis can be differentiated from residual/recurrent tumor by proton MR spectroscopy. METHODS: We studied the effects of interstitial brachytherapy on the brains of healthy monkeys and in humans with glioblastoma multiforme. The effects of radiation therapy on normal brain tissue in monkeys were assessed with sequential proton MR spectroscopic studies 1 week to 6 months after brachytherapy. Proton MR spectroscopy was also performed in five patients with residual/recurrent glioblastoma multiforme (three of whom had radiation necrosis after brachytherapy), seven patients with newly diagnosed untreated glioblastoma multiforme, and 16 healthy volunteers, who served as a control group. RESULTS: In monkeys, the ratio of N-acetylaspartate (NAA) to creatine-phosphocreatine (Cr) and the ratio of choline-containing compounds (Cho) to Cr of the reference point were significantly lower 1 week after brachytherapy than before treatment. The ratio of NAA to Cho of the irradiated area tended to be higher 1 week after brachytherapy than before irradiation. These peak metabolic ratios showed characteristic changes 6 months after treatment. In two of three monkeys, lipid signal was elevated 6 months after irradiation. In the clinical study, the ratio of NAA to Cho in the area of radiation necrosis was significantly different from that in glioblastoma multiforme when compared with the contralateral hemisphere after irradiation. In addition, lipid signal was detected in all patients with radiation necrosis. CONCLUSION: It might be possible to use proton MR spectroscopy to differentiate radiation necrosis from residual/recurrent glioblastoma multiforme on the basis of comparisons with the contralateral hemisphere after radiation therapy. PMID- 9367330 TI - Transtemporal power- and frequency-based color-coded duplex sonography of cerebral veins and sinuses. AB - PURPOSE: To determine the ability of transtemporal power- and frequency-based transcranial color-coded duplex sonography to aid in the assessment of cerebral veins and sinuses, as well as to provide reference data for flow direction and velocity. METHODS: Using a color duplex device equipped with a 2.0/2.5-MHz sector scan, we insonated 120 healthy volunteers and three patients with cerebral venous thrombosis. RESULTS: In subjects 20 to 59 years old, deep middle cerebral veins were identified in 88%, basal veins in 97%, straight sinuses in 60%, and transverse sinuses in 42%. The corresponding values for subjects 60 to 79 years old were 53%, 86%, 23%, and 20%, respectively. Velocities were highest in transverse and straight sinuses, slower in basal veins, and slowest in deep middle cerebral veins. Flow was directed lateromedially in the deep middle cerebral vein, rostrocaudally in the basal vein and straight sinus, and mediolaterally in the transverse sinus. Two patients with straight sinus thromboses showed reversed flow direction in the basal veins, and one patient with superior sagittal sinus thrombosis showed elevated velocities in a deep middle cerebral vein. CONCLUSION: Transtemporal power- and frequency-based color coded duplex sonography enabled imaging and velocity measurements in deep cerebral veins in subjects 20 to 59 years old, but detection of the straight and transverse sinuses was low. In older subjects, only the basal vein was regularly assessed. PMID- 9367329 TI - Regional dynamic signal changes during controlled hyperventilation assessed with blood oxygen level-dependent functional MR imaging. AB - PURPOSE: To quantitate the amplitude changes and temporal dynamics of regional functional MR imaging signals during voluntary hyperventilation using blood oxygen level-dependent contrast echo-planar imaging. METHODS: Seven male subjects were studied during voluntary hyperventilation (PetCO2 = 20 mm Hg) regulated by capnometry. Measurements were made on multisection echo-planar MR images obtained with parameters of 1000/66 (repetition time/echo time), flip angle of 30 degrees, and voxel size of 3 x 3 x 5 mm3. Sensitivity of the functional MR imaging signal to changes in PetCO2, time delays in relation to PetCO2 changes, and time constants of functional MR imaging signal changes were assessed on a region-by region basis. RESULTS: Within 20 seconds of starting hyperventilation, rapid and substantial decreases in the functional MR imaging signal (by as much as 10%) were measured in areas of gray matter, which were significantly greater than the modest changes observed in white matter. Regional-specific effects in areas of the frontal, occipital, and parietooccipital cortex were stronger than in subcortical regions or in the cerebellum. Signal decreases measured with functional MR imaging were significantly delayed with respect to the reduction in PetCO2. Apparent differences between regional time constants did not reach statistical significance. CONCLUSION: Regional and gray-white matter differences in functional MR imaging signal changes during controlled hyperventilation may reflect differences in metabolic activity, vascular regulation, and/or capillary density. When measuring brain activation with functional MR imaging, arterial PCO2 differences due to unregulated respiration may confound interpretation of activation-related functional MR imaging signal changes. PMID- 9367331 TI - Reversible pontine ischemia caused by acetazolamide challenge. AB - We report the findings in a patient with a midbasilar artery stenosis in whom reversible ischemic neurologic deficits developed during cerebral blood flow imaging with acetazolamide challenge. The potential for ischemic complications from acetazolamide challenge is discussed. PMID- 9367332 TI - Sarcoid involvement of the supraorbital nerve: MR and histologic findings. AB - We report the MR and histologic findings of neurosarcoidosis presenting as a mass involving the supraorbital nerve in a 29-year-old woman in whom this was the first manifestation of the disease. The features and associations of neurosarcoidosis and the response to treatment are discussed. PMID- 9367333 TI - MR of the eye with retrobulbar anesthesia. AB - MR imaging with retrobulbar anesthesia was performed in eight patients with uveal melanoma. Injection of 2 mL prilocain hydrochloride in 2% epinephrin into the eye muscle cone resulted in improved image quality in seven patients, without side effects. Ocular MR imaging can be indicated to clarify indeterminate sonographic findings in cases of extrascleral growth or to exclude optic nerve invasion in patients with tumors located at the posterior pole of the globe. PMID- 9367334 TI - Measurement of hippocampal T2 in epilepsy. PMID- 9367335 TI - Dosimetry of radiologic techniques for dental implant planning. PMID- 9367336 TI - MR analysis of the corpus callosum. PMID- 9367337 TI - CT angiography of the circle of Willis: is spiral technology always necessary? PMID- 9367338 TI - Does papaverine cause endothelial injury in clinically relevant doses? PMID- 9367339 TI - Environmental pollution, pesticides, and the prevention of cancer: misconceptions. AB - The major causes of cancer are: 1) smoking, which accounts for about a third of U.S. cancer and 90% of lung cancer; 2) dietary imbalances: lack of sufficient amounts of dietary fruits and vegetables. The quarter of the population eating the fewest fruits and vegetables has double the cancer rate for most types of cancer than the quarter eating the most; 3) chronic infections, mostly in developing countries; and 4) hormonal factors, influenced primarily by lifestyle. There is no cancer epidemic except for cancer of the lung due to smoking. Cancer mortality rates have declined by 16% since 1950 (excluding lung cancer). Regulatory policy that focuses on traces of synthetic chemicals is based on misconceptions about animal cancer tests. Recent research indicates that rodent carcinogens are not rare. Half of all chemicals tested in standard high-dose animal cancer tests, whether occurring naturally or produced synthetically, are "carcinogens"; there are high-dose effects in rodent cancer tests that are not relevant to low-dose human exposures and which contribute to the high proportion of chemicals that test positive. The focus of regulatory policy is on synthetic chemicals, although 99.9% of the chemicals humans ingest are natural. More than 1000 chemicals have been described in coffee: 28 have been tested and 19 are rodent carcinogens. Plants in the human diet contain thousands of natural "pesticides" produced by plants to protect themselves from insects and other predators: 63 have been tested and 35 are rodent carcinogens. There is no convincing evidence that synthetic chemical pollutants are important as a cause of human cancer. Regulations targeted to eliminate minuscule levels of synthetic chemicals are enormously expensive: the Environmental Protection Agency has estimated that environmental regulations cost society $140 billion/year. Others have estimated that the median toxic control program costs 146 times more per hypothetical life-year saved than the median medical intervention. Attempting to reduce tiny hypothetical risks has other costs as well: if reducing synthetic pesticides makes fruits and vegetables more expensive, thereby decreasing consumption, then the cancer rate will increase, especially for the poor. The prevention of cancer will come from knowledge obtained from biomedical research, education of the public, and lifestyle changes made by individuals. A reexamination of priorities in cancer prevention, both public and private, seems called for. PMID- 9367340 TI - Introduction: evolving roles for ubiquitin in cellular regulation. PMID- 9367341 TI - Targeting of substrates to the 26S proteasome. AB - The ubiquitin-proteasome pathway is the principal mechanism for the turnover of short-lived proteins in eukaryotic cells. In this pathway, the covalent ligation of ubiquitin to the substrate is a signal for recognition by the 26S proteasome. Recent studies indicate that targeting of substrates of the ubiquitin pathway to the proteasome is usually accomplished by the ligation of a polyubiquitin chain assembled through K48-G76 isopeptide bonds, rather than by ligation of monoubiquitin. In addition to providing benefits in signal generation, recognition, and persistence, assigning the proteolytic targeting function to a specific specific type of polyubiquitin chain may allow monoubiquitin or polyubiquitin chains of novel structures to serve distinct targeting functions. Besides polyubiquitinated substrates, the proteasome also degrades an unknown number of proteins that are recognized without undergoing ubiquitination. Ornithine decarboxylase is the prototype ubiquitin-independent substrate; it is targeted to the proteasome through noncovalent interaction with a specific protein factor known as antizyme. The existence of ubiquitin-independent substrates of the proteasome raises important questions about the nature of the substrate- and proteasome-based elements that cooperate to bring about the targeting of substrates to this novel proteolytic complex. PMID- 9367342 TI - Cell cycle regulation by the ubiquitin pathway. AB - In the past 2 years, two ubiquitin-dependent proteolytic pathways have been established as important players in the regulation of the cell division cycle. In S. cerevisiae, the entry into S phase requires ubiquitin-mediated degradation of a cdk inhibitor, p40Sic1, in a pathway that involves the E2 enzyme Cdc34. Recent studies reviewed herein show that the Cdc34 pathway targets phosphorylated substrates. A second pathway that regulates chromosome segregation and mitotic exit by degrading anaphase inhibitors and mitotic cyclins involves a different E2 and a large molecular weight E3 complex, called the anaphase-promoting complex or cyclosome. This pathway targets substrates containing one or more destruction box motif. PMID- 9367344 TI - Calcium signaling in the cell nucleus. AB - Regulation of Ca2+ in the nucleus is a debated issue, essentially due to the presence in the envelope of the pores, which are large enough to permit the passive traffic of small molecules like Ca2+. Work with a number of cell systems has shown that Ca2+ diffuses freely in and out of the nucleus, whereas other studies have suggested instead that the nuclear envelope could become an efficient Ca2+ filter: electrophysiological work has shown that it could become impermeable to ions, and persistent nucleus cytoplasmic Ca2+ gradients have been documented in various cell types. The problem of the control of nuclear Ca2+ thus is still open: mechanisms for gating of the pores, based on the state of depletion of the cell Ca2+ stores, have been proposed. Irrespective of the mechanisms for possible pore gating, a final picture on the traffic of Ca2+ in and out of the nucleus must also include the Ca2+ pump as well as the InsP3 and cyclic ADP ribose-modulated Ca2+ channels in the envelope. The channels can be activated by their ligands from inside the nucleus, producing Ca2+ transients in the nucleoplasm; the machinery for producing InsP3 has been documented in the envelope. Most Ca2+-sensitive nuclear functions are jointly modulated by Ca2+ and calmodulin: calmodulin-dependent kinases and the calmodulin-dependent phosphatase calcineurin have been documented in the nucleus. An interesting case for the modulation of intranuclear processes by calmodulin-dependent kinases is that of immediate early genes, i.e., CREB. Other Ca2+-modulated nuclear processes are calmodulin independent: chief among them is the intranucleosomal cleavage of chromatin and the fragmentation of nuclear proteins during apoptosis. PMID- 9367343 TI - Role of cysteine and glutathione in HIV infection and other diseases associated with muscle wasting and immunological dysfunction. AB - The combination of abnormally low plasma cystine and glutamine levels, low natural killer (NK) cell activity, skeletal muscle wasting or muscle fatigue, and increased rates of urea production defines a complex of abnormalities that is tentatively called "low CG syndrome." These symptoms are found in patients with HIV infection, cancer, major injuries, sepsis, Crohn's disease, ulcerative colitis, chronic fatigue syndrome, and to some extent in overtrained athletes. The coincidence of these symptoms in diseases of different etiological origin suggests a causal relationship. The low NK cell activity in most cases is not life-threatening, but may be disastrous in HIV infection because it may compromise the initially stable balance between the immune system and virus, and trigger disease progression. This hypothesis is supported by the coincidence observed between the decrease of CD4+ T cells and a decrease in the plasma cystine level. In addition, recent studies revealed important clues about the role of cysteine and glutathione in the development of skeletal muscle wasting. Evidence suggests that 1) the cystine level is regulated primarily by the normal postabsorptive skeletal muscle protein catabolism, 2) the cystine level itself is a physiological regulator of nitrogen balance and body cell mass, 3) the cyst(e)ine-mediated regulatory circuit is compromised in various catabolic conditions, including old age, and 4) cysteine supplementation may be a useful therapy if combined with disease-specific treatments such as antiviral therapy in HIV infection. PMID- 9367345 TI - Signaling elements involved in amino acid transport responses to altered muscle cell volume. AB - Skeletal muscle glutamine uptake via the transport system Nm is subject to rapid (t(1/2) = approximately 1 min) regulation after changes in cell volume by mechanisms that remain to be elucidated. Wortmannin (phosphatidylinositol 3 kinase inhibitor) but not rapamycin (inhibitor of p70S6 kinase activation) prevents both hypo-osmotic swelling-induced stimulation and hyperosmotic shrinkage-induced inhibition of Na+-dependent glutamine uptake in primary culture of rat skeletal muscle. G-protein inhibitors (cholera, pertussis toxins) also abolished responses of glutamine transport to cell volume changes whereas these responses were sustained in the presence of G-protein activators (MAS 7, lysophosphatidic acid). Swelling-induced activation of glutamine transport does not seem to involve release of autocrine factors because "conditioned" medium from swollen cells has no effect on previously unstimulated cells. System A amino acid transport exhibits responses to cell volume change that are opposite to those of system Nm, but these are also blocked by wortmannin. Active phosphatidylinositol 3-kinase appears to be required to enable muscle cells to exhibit rapid, volume-induced changes in amino acid transport when suitably stimulated. PMID- 9367346 TI - Inhibition of platelet-derived growth factor receptor tyrosine kinase inhibits vascular smooth muscle cell migration and proliferation. AB - Platelet-derived growth factors (PDGFs) and their receptors (PDGFRs) have been linked to vascular smooth muscle cell (SMC) migration and proliferation leading to atherosclerosis, restenosis, and chronic allograft rejection. This study describes the effect of CGP 53716, a specific PDGFR tyrosine kinase inhibitor on SMC proliferation and migration in vitro and in neointimal formation in vivo. CGP 53716 inhibited dose dependently tyrosine phosphorylation of both the known PDGFRs: the PDGFR-alpha and PDGFR-beta. In primary rat SMC cultures, a dose dependent inhibition of PDGF-AA and PDGF-BB induced migration, and tritiated thymidine incorporation of SMC was seen at nontoxic concentrations. After rat carotid artery ballooning injury in vivo, the migration of alpha-actin-positive cells on the luminal side of internal elastic lamina was decreased with 50 mg x kg(-1) x day(-1) of CGP 53716 from 38 +/- 10 (control group) to 4 +/- 2 (P<0.0001, Mann-Whitney U test, N=18). CGP 53716 did not inhibit the number of replicating bromodeoxyuridine (BrdU)-incorporating cells in the intima, media, or adventitia during BrdU labeling at 0-96 postoperative h, though it inhibited significantly (P<0.01) the replication of medial and intimal cells from 93 h onward. Intima/media ratio was inhibited by 40% after 14 days in the CGP 53716 treated group (P=0.028) after rat aortic denudation. The results indicate that inhibition of the PDGFR tyrosine kinase inhibits SMC migration and proliferation in vitro, SMC migration, and, to a lesser extent, proliferation after ballooning injury in vivo, confirming a causal role for activation of the PDGFR and the formation of neointimal lesions. PMID- 9367347 TI - Evaluation of the potential carcinogenicity of 60 Hz linear sinusoidal continuous wave magnetic fields in Fischer F344 rats. AB - Electric and magnetic fields (EMFs) associated with the production, transmission, and use of electricity are ubiquitous in industrialized societies. These fields are predominantly of low frequency (50/60 Hz) and are generally of low intensity. Review of the epidemiological evidence shows that the association between exposure to EMFs and cancer is weak and inconsistent, and generally fails to show a dose-response relationship. Moreover, in view of the methodological problems of these epidemiological studies, animal and laboratory studies are urgently needed to determine whether EMFs could be initiators and/or promoters of cancers. The objective of the present study was to determine whether chronic exposure to 60 Hz linear (single axis) sinusoidal, continuous-wave magnetic fields (MFs) of different intensities might increase the risk of leukemia and solid tumor development in rodents born and raised under these fields. Five groups of 50 female F344 rats were exposed for 20 h/day to 60 Hz MFs at intensities of <0.02 (sham controls), 2, 20, 200, and 2000 microT. Full body exposure to the different fields was administered for 104 wk starting from the prenatal period (2 days before birth) and continuing during lactation and weaning until late adult life. Body weight, survival, and clinical observations were evaluated in all groups of animals during in-life exposure. Necropsy was performed on all exposed and control animals that died, were found moribund, or were killed at termination of the study. To preserve and demonstrate the absence of any experimental bias, all clinical observations and pathological evaluations were conducted under "blinded" conditions. Fifty organs and tissues were evaluated in each animal, with special attention to the incidence of mononuclear cell leukemia, brain tumors, and mammary tumors. The findings from this chronic carcinogenicity study demonstrate that, under our defined experimental conditions, exposure to 60 Hz linear (single axis) sinusoidal, continuous wave MFs did not affect animal survival, solid tumor, or mononuclear cell leukemia development in female F344 rats. No statistically significant, consistent, positive dose-related trends with the number of tumor-bearing animals per study group could be attributed to MF exposure. PMID- 9367348 TI - Phenotype of transgenic mice overexpressing GLUT4 and hexokinase II in muscle. AB - To optimize glucose utilization, double transgenic mice were created by crossing mice overexpressing glucose transporter GLUT4 with mice overexpressing hexokinase (HKII) in muscle. Transgenic mice overexpressing GLUT4 alone have exhibited improvements in glucose tolerance and insulin action. In vitro studies of hexose uptake in soleus muscle from transgenic mice suggested that GLUT4 was limiting the glucose flux except at high glucose concentration, where hexokinase became the limiting step. In vivo, glucose tolerance was similar in GLUT4 and GLUT4/HKII mice, although stimulated plasma insulin values were significantly lower in the latter group. Insulin tolerance tests performed in diabetic GLUT4 vs. diabetic GLUT4/HKII transgenic mice yielded identical results. Again, endogenous insulin in GLUT4/HKII mice during a mild hyperglycemic clamp was stimulated by only two- vs. fourfold in GLUT4 mice. Although the overexpression of HKII alone resulted in increased glucose utilization in several muscles, the overexpression of GLUT4 plus HKII did not augment basal or stimulated in vivo glucose utilization compared to GLUT4 overexpression. In conclusion, GLUT4 is rate limiting for muscle glucose utilization but HKII might be important under hyperglycemia. The addition of HKII to GLUT4 overexpression is not sufficient to further augment glucose tolerance or insulin action. In GLUT4/HKII double transgenic mice, glucose clearance is tempered by a low insulin stimulated level. PMID- 9367349 TI - Ethanol down-regulates the transcription of microsomal triglyceride transfer protein gene. AB - Microsomal triglyceride transfer protein (MTP) plays a central role in the assembly and secretion of apoB-containing lipoproteins. In this study, we investigated the effect of ethanol on the expression of the large subunit of MTP in a human liver hepatoma cell line, the HepG2 cells. Exposure of HepG2 cells to low concentrations of ethanol reduced MTP mRNA levels in a concentration- and time-dependent manner. The level of MTP mRNA decreased significantly (P<0.05, 26% relative to pretreatment control) when the concentration of ethanol in the culture medium was 50 ppm (0.005%, v/v). Maximal suppression (-50%) was observed at 100 ppm ethanol; the MTP mRNA levels remained at 50% of control when the ethanol concentration was raised to 10,000 ppm. Furthermore, a 10-day ethanol treatment caused a significant 50% decrease in the MTP activity and apoB secretion rate in HepG2 cells. To investigate the molecular mechanisms underlying this phenomenon, we examined the effect of ethanol on the promoter activity of the MTP gene. Transient transfection analysis of human MTP promoter-driven luciferase gene expression showed that ethanol down-regulates MTP promoter activity in a manner parallel to that observed for mRNA levels. Deletion analysis suggested that the MTP promoter sequence contains a negative ethanol response element -612 to -142 bp upstream of the transcription start site. To evaluate the in vivo relevance of the effect of ethanol on MTP mRNA levels, rats were given a single oral dose of ethanol, with hepatic and intestinal MTP mRNA measured 3 h after dosing. Rats receiving 1 or 3 g/kg of ethanol exhibited substantially lower hepatic and intestinal MTP mRNA levels. Taken together, these results strongly suggest that ethanol can modulate the secretion of apoB-containing lipoproteins by down-regulating the expression of MTP large subunit, primarily through inhibiting the transcription of the MTP gene. PMID- 9367350 TI - Use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis to resolve mRNA and its protein product in one gel. AB - We demonstrate that it is possible to simultaneously resolve both an mRNA and its protein product by electrophoresis in a single SDS-polyacrylamide gel by using double labeling with [32P]H3PO4 and [35S]methionine, and an elongated 5% stacking gel atop the 10% resolving gel. The mRNA is resolved in the 5% gel; the protein, as expected, resolves in the 10% gel. Using a T7 expression system, we show that putative mRNA bands in the 5% gel are: 1) labeled only with 32P and not with 35S; 2) inducible with isopropylthiogalactopyranoside (needed to induce a T7 RNA polymerase gene under control of a lac promoter); 3) synthesized in the presence of rifampicin (T7 RNA polymerase is not inhibited by rifampicin); 4) degraded by base or RNase treatment; and 5) are largely resistant to DNase treatment. The mRNA bands were also evident in samples not treated with rifampicin. We used this technique to confirm previously published results that inhibition of expression by consecutive low-usage AGG arginine codons inserted near the 5' end of a test message in Escherichia coli is at the level of translation. PMID- 9367351 TI - Acute methionine load-induced hyperhomocysteinemia enhances platelet aggregation, thromboxane biosynthesis, and macrophage-derived tissue factor activity in rats. AB - A moderate elevation of plasma homocysteine is a risk factor for atherosclerosis and arterial and veinous thrombosis. However, the mechanisms leading to vascular disorders are poorly understood because studies that have investigated the potential atherothrombogenicity of hyperhomocysteinemia in vivo are scarce. Using a rat model, we were the first to show that dietary folic acid deficiency, a major cause of basal hyperhomocysteinemia, is associated with enhanced macrophage derived tissue factor and platelet activities. We proposed that an homocysteine induced oxidative stress may account for this hypercoagulable state. To determine the true thrombogenicity of moderate hyperhomocysteinemia and better understand its etiology, we have carried out an acute methionine load in control and folate deficient animals. When rats were fed the control diet, a transient fourfold increase in plasma homocysteine levels was observed 2 h after the methionine administration. As with prolonged dietary folic acid deficiency, this methionine load potentiated the platelet aggregation in response to thrombin and ADP as well as the thrombin-induced thromboxane synthesis. It also stimulated the basal and lipopolysaccharide-induced tissue factor activity of peritoneal macrophages. These prothrombotic effects were associated with an increased lipid peroxidation characterized by an elevation of plasma conjugated dienes, lipid hydroperoxides, and thiobarbituric acid-reactive substances. When rats were fed a folic acid deficient diet, the methionine load did not cause any further increase in plasma homocysteine concentration, platelet activation, macrophage tissue factor dependent coagulation, or lipoperoxidation. Altogether, our data showed that the prethrombotic state due to both the altered remethylation and transsulfuration pathways resulted from the moderate elevation of circulating homocysteine. We conclude that moderate hyperhomocysteinemia plays a role in the development of a thrombogenic state that might be mediated by the occurrence of oxidative stress. PMID- 9367352 TI - The amino-terminal fragment of human urokinase directs a recombinant chimeric toxin to target cells: internalization is toxin mediated. AB - In contrast to two-chain urokinase (uPA), a chemical conjugate between uPA and native saporin (a cytotoxic plant seed ribosome-inactivating protein) did not require plasminogen activator inhibitors to be internalized. To dissect this pathway, we constructed a chimera consisting of the amino-terminal fragment (ATF) of human urokinase fused to a saporin isoform (SAP-3). The chimeric ATF-SAP toxin was expressed in Escherichia coli, purified, and characterized for its ribosome inactivating activity. Besides being a potent inhibitor of protein synthesis in cell-free assays, ATF-SAP was specifically cytotoxic toward cells expressing human uPAR. Competition experiments indicated that both the human uPAR and the LDL-related receptor protein are involved in mediating the cell killing ability of ATF-SAP. We conclude that neither plasminogen activator inhibitors nor the catalytic moiety of urokinase are necessary to initiate these internalization pathways. Thus, saporin may play a role similar to plasminogen activator inhibitors in its ability to trigger internalization of uPAR-bound ligands through endocytic receptors. PMID- 9367353 TI - Beta2 integrins (CD11/CD18) promote apoptosis of human neutrophils. AB - Apoptosis of human polymorphonuclear neutrophils (PMN) is thought to be critical for the control of the inflammatory process, but the mechanisms underlying its regulation in physiological settings are still incompletely understood. This study was undertaken to test the hypothesis that the beta2 integrin (CD11/CD18) family of leukocyte adhesion molecules contributes to the control of activated PMN by up-regulating apoptosis. Apoptosis of isolated human PMN was investigated by 1) analysis of DNA content, 2) detection of DNA degradation, 3) morphological studies, and 4) measurement of CD16 expression on the cell surface. We found that beta2 integrins potentiated the tumor necrosis factor alpha (TNF-alpha) -induced apoptosis within 4 and 8 h after stimulation. The effect required aggregation of the beta2 integrin Mac-1 (CD11b/CD18), which was induced by antibody cross linking, and was independent of Fc receptors. An enhancement of apoptosis was also observed after migration of PMN through an endothelial cell monolayer. TNF alpha-induced apoptosis as well as potentiation by beta2 integrins was prevented by inhibition of tyrosine kinases with herbimycin A or genistein. The present study provides a new model for the regulation of PMN apoptosis by a functional cross-talk between beta2 integrins and TNF-alpha with a promoting role for the beta2 integrins. This mechanism, which allows enhanced elimination of previously emigrated PMN, may be critical to abate local inflammatory processes in vivo. PMID- 9367354 TI - Development of immortalized human cerebromicrovascular endothelial cell line as an in vitro model of the human blood-brain barrier. AB - The objective of this study was to generate an immortal cell line representative of specialized human brain microvascular endothelia forming the blood-brain barrier (BBB) in vivo. Human capillary and microvascular endothelial cells (HCEC) were transfected with the plasmid pSV3-neo coding for the SV40 large T antigen and the neomycin gene. The neomycin-resistant transfected cells overcame proliferative senescence, and after a 6-8 wk period of crisis produced immortalization-competent cell colonies. Single-cell clones of near-diploid genotype were isolated from these colonies, propagated, and characterized. Immortalized HCEC (SV-HCEC) exhibited accelerated proliferation rates, but remained serum and anchorage dependent and retained the characteristic cobblestone morphology at confluence. SV-HCEC displayed a stable nuclear expression of SV40 large T antigen, lacked the invasiveness of transformed cells, and maintained major phenotypic properties of early passage control cells including expression of factor VIII-related antigen, uptake of acetylated low density lipoprotein, binding of fluorescently labeled lectins, expression of transferrin receptor and transferrin receptor-mediated endocytosis, and high activities of the BBB-specific enzymes alkaline phosphatase and gamma-glutamyl transpeptidase. The diffusion of radiolabeled sucrose across SV-HCEC monolayers was fivefold lower than that observed with human lung microvascular endothelial cells. Furthermore, media conditioned by fetal human astrocytes increased the transendothelial electrical resistance of SV-HCEC monolayers by 2.5-fold. Therefore, this newly established human cell line expressing the specialized phenotype of BBB endothelium may serve as a readily available in vitro model for studying the properties of the human BBB. PMID- 9367355 TI - Atherosclerosis, autoimmunity, and vascular-associated lymphoid tissue. PMID- 9367356 TI - The molecular basis of virulence of the encephalitogenic flaviviruses. PMID- 9367357 TI - Analysis of a recombinant dengue-2 virus-dengue-3 virus hybrid envelope protein expressed in a secretory baculovirus system. AB - In a step towards a tetravalent dengue virus subunit vaccine which is economical to produce, highly immunogenic and stable, a hybrid dengue virus envelope (E) protein molecule has been constructed. It consists of 36 amino acids from the membrane protein, the N-terminal 288 amino acids of the dengue-2 virus E protein plus amino acids 289-424 of the dengue-3 virus E protein. It has been engineered for secretory expression by fusion to a mellitin secretory signal sequence and truncation of the hydrophobic transmembrane segment. Using the baculovirus expression system and serum-free conditions, more than 95% of recombinant dengue 2 virus-dengue-3 virus hybrid E protein (rD2D3E) was secreted into the cell culture supernatant in a stable form with multiple features indicative of preserved conformation. The hybrid molecule reacted with a panel of dengue virus- and flavivirus-specific MAbs which recognize linear or conformational epitopes on dengue virions. Human dengue virus-specific antisera also reacted with the protein. The hybrid rD2D3E protein was able to inhibit the in vitro binding of dengue-2 and dengue-3 viruses to human myelomonocytic cells, suggesting that the receptor-binding epitope(s) was preserved. Adjuvant-free immunization with the hybrid protein induced an antibody response to both dengue-2 and dengue-3 virus in outbred mice, comparable in strength to that of individual rD2E and rD3E proteins. Notably, these antibody responses were primarily of the IgG2a and IgG2b isotype. A strong dengue virus cross-reactive T cell response was also induced in the mice, suggesting that dengue virus hybrid E proteins could form the basis of an efficacious multivalent dengue virus vaccine. PMID- 9367358 TI - Immune responses to the hepatitis C virus NS4A protein are profoundly influenced by the combination of the viral genotype and the host major histocompatibility complex. AB - The interaction between the host major histocompatibility complex (MHC) and the genotype of the hepatitis C virus (HCV) was analysed using synthetic full-length non-structural (NS) 4A proteins, residues 1658-1712, of genotypes 1b, 2b, 3a, 4a and 5a. Human and murine antibodies specific for the five NS4A genotypes analysed focused on residues 1688-1707. In immunized B10 H-2 congenic mice, the H-2d, H-2f and H-2s haplotypes were good responders to NS4A, irrespective of the viral genotype. In contrast, the H-2k haplotype was a low or non-responder to all NS4A genotypes, except for genotype 2b. Also, H-2f- and H-2s-restricted NS4A genotype 1b-specific T-cells focused on residues 1670-1679 and 1683-1692, respectively, whereas H-2k-restricted NS4A genotype 2b-specific T-cells focused on the carboxy terminus. Interestingly, H-2f-restricted genotype 1b-specific T-cells did not cross-react with T-cell site analogues of seven other genotypes, whereas the H-2s restricted, genotype 1b-specific T-cells cross-reacted with genotypes 1a, 4a and 5a. Thus the combination of viral genotype and host MHC profoundly influences the ability to mount an HCV NS4A-specific immune response. PMID- 9367359 TI - Hepatitis C virus negative strand RNA is not detected in peripheral blood mononuclear cells and viral sequences are identical to those in serum: a case against extrahepatic replication. AB - Peripheral blood mononuclear cells (PBMCs) from 27 hepatitis C virus (HCV) infected patients were analysed for the presence of HCV negative strand RNA with strand-specific Tth-based RT-PCR. No negative strand RNA was detected in any sample, and positive strand HCV sequences amplified from PBMCs were identical to those found in serum. These findings suggest that HCV does not replicate in PBMCs, and the presence of HCV sequences at this site is compatible with passive virus adsorption and/or contamination by circulating virus. PMID- 9367360 TI - Cloning and characterization of a complete open reading frame of the hepatitis C virus genome in only two cDNA fragments. AB - The synthesis of long cDNA molecules encoding the complete genome of RNA viruses has recently been demonstrated; this major improvement has numerous practical applications such as construction of infectious cDNA clones or study of sequence variability at the level of a single RNA molecule. Using hepatitis C virus (HCV) as a model, we established an RT-PCR technique for amplification of cDNA fragments with a length of about 5 kb. The RT reaction was carried out with a Moloney murine leukaemia virus reverse transcriptase lacking detectable RNase H activity. For PCR reactions an enzyme mix containing Taq and Pwo DNA polymerases was used. Hot start and addition of 5% DMSO were also important to efficiently achieve long PCR products. About 10(6) HCV genome equivalents/ml in serum were needed in order to amplify the HCV genome in only two cDNA fragments covering about 98% of the complete genome. Analysis of the HCV quasi-species is also possible by this method as shown by sequencing of the hypervariable region 1 (HVR1) after cloning of cDNAs. The integrity of the long cDNA clones was proven by (1) restriction analyses, (2) partial sequencing and (3) expression of respective gene products. In vitro transcribed cDNAs were translated in rabbit reticulocyte lysate. Structural and nonstructural HCV proteins were identified by immunoprecipitation using patient serum. These results suggest that the two cDNA clones encode a complete and functional open reading frame of HCV. PMID- 9367361 TI - Molecular cloning of a defective hepatitis C virus genome from the ascitic fluid of a patient with hepatocellular carcinoma. AB - A defective hepatitis C virus (HCV) genome in the ascitic fluid of a patient with hepatocellular carcinoma was cloned and sequenced up to the 3' poly(U) stretch. When compared with the published Taiwanese HCV sequence, this defective genome contained deletions of single nucleotides at eight sites, double nucleotides at two sites, triple nucleotides at four sites, quadruple nucleotides at one site and replacement of a short stretch of sequence at one site. For comparison, the corresponding regions containing these mutations were also cloned from a serum sample from this patient. Except for deletions of two triple nucleotides in the hypervariable region, the reading frames of all serum-derived clones were intact. The defective HCV genome encoded a truncated core protein with 90 amino acid residues (the last 20 amino acid residues came from a different reading frame), whereas the serum-derived genome encoded a full-length core protein. When expressed in Huh-7 cells, these two proteins were localized to the nucleus and cytoplasm, respectively. Using specific primer-sets, ascites- and serum-derived genomes were each detected alone in ascitic fluid and serum samples, respectively, whereas both sequences were present in ascitic mononuclear cells. The defective sequence thus constituted the major virus population in the ascitic fluid whereas a putative helper genome coexisted with it inside the ascitic mononuclear cells. This sequence is possibly a defective and interfering genome. PMID- 9367362 TI - Sequence variation and phylogenetic analysis of envelope glycoprotein of hepatitis G virus. AB - A transfusion-transmissible agent provisionally designated hepatitis G virus (HGV) was recently identified. In this study, we examined the variability of the HGV genome by analysing sequences in the putative envelope region from 72 isolates obtained from diverse geographical sources. The 1561 nucleotide sequence of the E1/E2/NS2a region of HGV was determined from 12 isolates, and compared with three published sequences. The most variability was observed in 400 nucleotides at the N terminus of E2. We next analysed this 400 nucleotide envelope variable region (EV) from an additional 60 HGV isolates. This sequence varied considerably among the 75 isolates, with overall identity ranging from 79.3% to 99.5% at the nucleotide level, and from 83.5% to 100% at the amino acid level. However, hypervariable regions were not identified. Phylogenetic analyses indicated that the 75 HGV isolates belong to a single genotype. A single-tier distribution of evolutionary distances was observed among the 15 E1/E2/NS2a sequences and the 75 EV sequences. In contrast, 11 isolates of HCV were analysed and showed a three-tiered distribution, representing genotypes, subtypes, and isolates. The 75 isolates of HGV fell into four clusters on the phylogenetic tree. Tight geographical clustering was observed among the HGV isolates from Japan and Korea. PMID- 9367363 TI - Inhibition of pestivirus infection in cell culture by envelope proteins E(rns) and E2 of classical swine fever virus: E(rns) and E2 interact with different receptors. AB - Pure preparations of envelope glycoproteins E(rns) and E2 of classical swine fever virus (CSFV) synthesized in insect cells were used to study infection of porcine and bovine cells with the pestiviruses CSFV and bovine viral diarrhoea virus (BVDV). Almost 100% inhibition of infection of porcine kidney cells with CSFV was produced by 100 microg/ml E(rns). After removal of the virus no E(rns) was needed in the overlay medium (growth medium) to maintain this level of inhibition. In contrast, 100% inhibition of infection of porcine kidney cells with CSFV by 10 microg/ml E2 was only achieved when E2 was added to the overlay medium. When E2 was omitted, a maximum of 50% inhibition was achieved. This indicated that after the virus and E2 were removed from the cells, infection still occurred, by virus particles which were still bound to the cell surface. Treatment with 100 microg/ml E(rns) released these particles from the cell surface. Furthermore, E(rns) bound irreversibly to the surface of cells susceptible or unsusceptible to pestivirus infection and cell-to-cell spread of CSFV was completely inhibited by E2 but not by E(rns). These results demonstrated that E(rns) and E2 interacted with different cell surface receptors. Inhibition of BVDV infection of porcine and bovine cells by CSFV E2 suggested that CSFV E2 and BVDV E2 share an identical receptor. BVDV strain 5250 isolated from pigs was efficiently inhibited by CSFV E(rns), whereas several BVDV strains isolated from cattle were not, suggesting that the conformation of E(rns) plays a role in host tropism. PMID- 9367364 TI - Identification and subcellular localization of a 41 kDa, polyprotein 1ab processing product in human coronavirus 229E-infected cells. AB - The translation products of the human coronavirus (HCV) 229E open reading frames 1a and 1b, the polyproteins 1a and 1ab, are processed by virus-encoded proteinases. One of the key enzymes in this process is a chymotrypsin-like enzyme, the 3C-like proteinase. In this study we have identified an ORF 1b encoded, 41 kDa processing product in HCV 229E-infected cells by using a monoclonal antibody with defined specificity. We show that this polypeptide is released from polyprotein 1ab by 3C-like proteinase-mediated cleavage of the peptide bonds Gln-6110/Gly-6111 and Gln-6458/Ser-6459. Also, we have investigated the subcellular localization of the 41 kDa processing product. Immunofluorescence microscopy revealed a punctate, perinuclear distribution of the 41 kDa polypeptide in infected cells and an identical subcellular localization was observed for three additional pp1ab-derived polypeptides. In contrast, the virus nucleocapsid protein showed a homogeneous cytoplasmic localization. PMID- 9367365 TI - Identification of residues critical for the human coronavirus 229E receptor function of human aminopeptidase N. AB - Aminopeptidase N (APN) is the major cell surface receptor for group 1 coronaviruses. In this study, we have isolated and characterized a feline APN cDNA and shown that the transfection of human embryonic kidney cells with this cDNA renders them susceptible to infection with the feline coronavirus feline infectious peritonitis virus, the human coronavirus (HCV) 229E and the porcine coronavirus porcine transmissible gastroenteritis virus. By using chimeric APN genes, assembled from porcine and feline sequences, we have shown that, analogously to the human APN protein, a region within the amino-terminal part of the feline APN protein (encompassing amino acids 132-295) is essential for its HCV 229E receptor function. Furthermore, by comparing the relevant feline, human and porcine APN sequences, we were able to identify a hypervariable stretch of eight amino acids that are more closely related in the feline and human APN proteins than in the porcine APN molecule. Using PCR-directed mutagenesis, we converted this stretch of amino acids within the porcine APN molecule to the corresponding residues of the human APN molecule. These changes were sufficient to convert porcine APN into a functional receptor for HCV 229E and thus define a small number of residues that are critically important for the HCV 229E receptor function of human APN. PMID- 9367366 TI - Structural, antigenic and immunogenic relationships between European brown hare syndrome virus and rabbit haemorrhagic disease virus. AB - The capsid protein of a French isolate of the European brown hare syndrome virus (EBHSV) was expressed in the baculovirus system. The recombinant EBHSV (rEBHSV) capsid protein was able to self-assemble into virus-like particles (VLPs). The VLPs were indistinguishable from the infectious EBHSV and displayed morphological characteristics similar to those we have described for the VLPs resulting from the expression of the capsid protein of rabbit haemorrhagic disease virus (RHDV), a closely related calicivirus. Cross-protection experiments showed that vaccination with rEBHSV particles did not protect rabbits against an RHDV challenge. A set of monoclonal antibodies (MAbs) was raised against rEBHSV capsid protein and used together with anti-RHDV and anti-EBHSV MAbs produced against native viruses to study the antigenic relationships between the two caliciviruses. All six anti-EBHSV MAbs delineated discontinuous epitopes; two of them reacted with specific surface epitopes and the remaining four reacted with internal epitopes which were also present in rRHDV. All anti-RHDV MAbs were monospecific; three reacted with surface linear epitope(s), two reacted with internal linear epitope(s) and one with a surface conformational epitope. On the basis of all these results, a classification of RHDV and EBHSV as two serotypes of a single serogroup is proposed. PMID- 9367367 TI - Creation of an infectious recombinant Sendai virus expressing the firefly luciferase gene from the 3' proximal first locus. AB - A genetic engineering approach was made to generate a recombinant non-segmented negative-strand RNA virus, Sendai virus (SeV) of the family Paramyxoviridae, that expresses firefly luciferase. The DNA construct containing the entire open reading frame (ORF) of the luciferase gene followed by the SeV transcription stop and restart signals connected with the conserved intergenic three nucleotides was inserted immediately before the ORF of the viral 3'-proximal nucleocapsid (N) protein gene in a full-length SeV cDNA copy. After intracellular expression of full-length antigenomic transcripts from the engineered cDNA and of the viral n ucleocapsid protein and RNA polymerase from the respective plasmids, a recombinant SeV expressing luciferase activity at a high level was recovered, although the tendency of this particular reporter gene product to aggregate in cells made it difficult to estimate the maximum level of expression. The increase in genome length brought about by inserting 1728 nucleotides into the 15,384 nucleotide parental SeV was associated with reduced plaque size, slightly slower replication kinetics and a severalfold decrease in yield of the virus. The inserted luciferase gene was stably maintained after numerous rounds of replication by serial passages in chick embryos. These results indicate the potential utility of SeV as a novel expression vector. PMID- 9367368 TI - Differential induction of cytotoxicity and apoptosis by influenza virus strains of differing virulence. AB - Two influenza viruses of differing virulence, clone 7a (virulent for humans and ferrets) and A/Fiji (attenuated for both species), induced differential levels of cytotoxicity (as measured by release of lactate dehydrogenase from cells) and apoptosis (as determined by altered nuclear morphology or flow cytometry) in MDCK and U-937 cells. Clone 7a induced more apoptosis and cytotoxicity than A/Fiji, despite the fact that its infectious virus yields were similar to or less than those for A/Fiji. This indicates a greater capacity of clone 7a to induce the two phenomena. Nevertheless the replication process was clearly essential, since UV irradiated virus induced little or no apoptosis, and apoptosis occurred as a late event post-infection. The possible relevance of these findings to destruction of host cells by influenza virus in vivo is discussed. PMID- 9367369 TI - Alteration of the actin-based cytoskeleton by rabies virus. AB - We investigated the effect of rabies virus infection on the actin cytoskeleton using various techniques. Confocal microscopic examination of rabies virus infected neuroblastoma cells at late stages of infection revealed a dramatic decrease in F-actin staining. The results of a fluorimetric assay with pyrenylated actin indicated that purified rabies virus nucleocapsid has no direct action on the kinetics of actin polymerization and only a weak effect on the final extent of polymerization. Video-microscopy experiments with purified components showed that rabies virus nucleocapsid inhibits the actin-bundling effect induced by dephospho-synapsin I, a neuron-specific protein which is known to exert a control on the actin-based cytoskeleton. Thus, the observed decrease in F-actin staining in infected cells might be ascribed to an indirect action of rabies nucleocapsid on the effects of actin-binding proteins such as synapsin I. PMID- 9367370 TI - Sequence variation of the glycoprotein gene identifies three distinct lineages within field isolates of viral haemorrhagic septicaemia virus, a fish rhabdovirus. AB - To evaluate the genetic diversity of viral haemorrhagic septicaemia virus (VHSV), the sequence of the glycoprotein genes (G) of 11 North American and European isolates were determined. Comparison with the G protein of representative members of the family Rhabdoviridae suggested that VHSV was a different virus species from infectious haemorrhagic necrosis virus (IHNV) and Hirame rhabdovirus (HIRRV). At a higher taxonomic level, VHSV, IHNV and HIRRV formed a group which was genetically closest to the genus Lyssavirus. Compared with each other, the G genes of VHSV displayed a dissimilar overall genetic diversity which correlated with differences in geographical origin. The multiple sequence alignment of the complete G protein, showed that the divergent positions were not uniformly distributed along the sequence. A central region (amino acid position 245-300) accumulated substitutions and appeared to be highly variable. The genetic heterogeneity within a single isolate was high, with an apparent internal mutation frequency of 1.2 x 10(-3) per nucleotide site, attesting the quasispecies nature of the viral population. The phylogeny separated VHSV strains according to the major geographical area of isolation: genotype I for continental Europe, genotype II for the British Isles, and genotype III for North America. Isolates from continental Europe exhibited the highest genetic variability, with sub-groups correlated partially with the serological classification. Neither neutralizing polyclonal sera, nor monoclonal antibodies, were able to discriminate between the genotypes. The overall structure of the phylogenetic tree suggests that VHSV genetic diversity and evolution fit within the model of random change and positive selection operating on quasispecies. PMID- 9367371 TI - Sequence determination and phylogenetic analysis of the Akabane bunyavirus S RNA genome segment. AB - The nucleotide sequence of the small (S) RNA segment of Akabane (AKA) bunyavirus was determined. The segment is 858 nucleotides long and contains two overlapping open reading frames (ORFs), which encode the nucleocapsid (N) and nonstructural (NSs) proteins, consistent with other bunyaviruses. Comparisons with the Aino virus S RNA sequence indicated that there is 73.5% identity in nucleotide sequence. However, the sequence identity of the 5' non-coding region of the genomic RNA between these two viruses is only 55%. The N ORFs from 20 Japanese and 2 Australian isolates of AKA virus were sequenced and subjected to phylogenetic analysis. This suggested that AKA virus has evolved in multiple lineages. Twenty-three isolates were grouped into three major clusters, and the cluster which includes recent isolates was subdivided into two branches. Thus, phylogenetic analysis of the AKA virus N protein gene gives a greater insight into bunyavirus evolution. PMID- 9367372 TI - Variability of the NS(S) protein among Rift Valley fever virus isolates. AB - Eighteen strains of Rift Valley fever (RVF) virus collected over a period of 38 years and isolated from diverse localities in Africa and from various hosts (human, animal and arthropod) were investigated by RT-PCR followed by sequencing of the NS(S) protein coding region. This region was chosen to analyse variability because, in contrast to the N protein, the NS(S) protein differs in various phleboviruses and there exists an RVF virus (clone 13) in which 70% of the NS(S) ORF is deleted, suggesting that this sequence is under a weak selective pressure. Sequence data indicated that percentage divergence among isolates ranged from 0 to 9.6% at the nucleotide level and from 0 to 9.5% at the amino acid level. Phylogenetic analysis based on the NS(S) gene revealed two major lineages: Egyptian and sub-Saharan. This led to the establishment of the relatedness between strains and insights into the NS(S) protein, the function of which is still undetermined. Alignment of the deduced amino acid sequences indicated that the cysteine residues are conserved, as are several motifs representing potential phosphorylation sites. PMID- 9367373 TI - Dinucleotide and stop codon frequencies in single-stranded RNA viruses. AB - To identify potential selection pressures which lead to RNA sequence conservation, we examined the occurrence rates of dinucleotides in 64 single stranded RNA virus genomes. These viruses may offer a particular insight into these pressures since their RNA-dependent RNA polymerases lack proofreading capability. This potentiates introduction of mutations into their genomes, yet unidentified selection processes conserve the genomes to a large degree. We report a strong inverse correlation between the C+G content and the occurrence of the CpG dinucleotide (r=0.71) in the RNA virus genomes, in contrast to earlier reports (Karlin et al., 1994, Journal of Virology 68, 2889-2897). We also detected significant suppression of UpA, correlating inversely with genomic U+A content. These suppressions are coupled with over-representation of the complementary pair of dinucleotides, CpA and UpG. In addition, we highlight the fact that odds ratios for dinucleotides are not independent variables, a situation apparently not widely appreciated in the literature. This led us to view the over-representation of CpA and UpG as a consequential outcome of UpA and CpG suppression in the virus genomes. Potential factors influencing these disturbances are discussed. In addition, higher than random incidence was observed for 'out-of-frame' stop codons in the viral RNA genomes, with some preferences for individual codons being exhibited by certain virus groups. The UAG codon appeared more common in the +1 frame, the UGA in the -1 frame. PMID- 9367374 TI - Investigation of population diversity of human immunodeficiency virus type 1 in vivo by nucleotide sequencing and length polymorphism analysis of the V1/V2 hypervariable region of env. AB - In this study we have analysed variability in the V1 and V2 regions of human immunodeficiency virus type 1 (HIV-1) proviral sequences amplified from lymphoid tissue, brain and other non-lymphoid tissue collected at autopsy from three HIV-1 infected individuals with giant cell encephalitis. We found no evidence for any tissue-specific grouping of variants in the V1/V2 regions, in contrast to previous comparisons of sequences in the V3 region, but consistent with the existence of evolutionarily distinct lineages previously observed in these study subjects by sequence comparisons of the p17gag gene. Examination of inferred amino acid sequences from V1 and V2 revealed no correlations between tissue origin with overall charge, length or number of glycosylation sites. Length polymorphism analysis is a rapid method to compare whole populations of HIV-1 variants within a sample, and provides information on the length and diversity of the V1 and V2 hypervariable regions. Based upon a comparison of 42 individuals with CD4 counts ranging from 802 to < 1 at time of death, we found no evidence for changes in the length of V2 with development of AIDS. Using the number of length variants in the V1 and V2 hypervariable region as a marker of the overall degree of variability within HIV populations, we found no evidence for an increase or a decrease in diversity between those with and without AIDS defining illness. PMID- 9367375 TI - Cell lines susceptible to infection are permeabilized by cleaved and solubilized outer layer proteins of rotavirus. AB - It has previously been shown that trypsinized triple-layered particles of rotavirus induce destabilization of liposomes and membrane vesicles in the absence of Ca2+, a condition which leads to solubilization of the outer capsid proteins of the virus. In this work, we have studied the relationship between outer capsid solubilization and permeabilization of membrane vesicles, monitoring particle and vesicle size simultaneously by changes in light scattering. Permeabilization of intact cells induced by solubilized outer capsid proteins was monitored by following the rate of entry of ethidium bromide into the cells. Solubilized outer capsid proteins separated from double-layered particles induced vesicle permeabilization. Solubilization of the outer capsid preceded and was required for vesicle or cell permeabilization. Membrane damage induced by rotaviral outer proteins was not repaired upon addition of 1 mM Ca2+ to the medium. Rotavirus infection and cell permeabilization were correlated in six different cell lines tested. This phenomenon might be related to the mechanism of virus entry into the cell. We propose a new model for rotavirus internalization based on the permeabilizing ability of outer capsid proteins and the cycling of trapped calcium in the endosomal compartment. PMID- 9367376 TI - Complete nucleotide sequence of Colorado tick fever virus segments M6, S1 and S2. AB - The nucleotide sequences of the tenth (M6), eleventh (S1) and twelfth (S2) dsRNA genomic segments of the Florio strain (N-7180) of Colorado tick fever virus were determined and found to be 675, 998 and 1884 bp, respectively, in length. A nonanucleotide motif and a hexanucleotide motif were found to be highly conserved in the 5' and 3' non-coding regions (NCRs), respectively, of the three segments. The first and last three nucleotides of each segment were of inverted complementarity, and segment-specific inverted terminal repeats were detected in the NCRs of the three segments. These findings suggest the occurrence of intracellular panhandle structures for the RNA transcripts. A readthrough phenomenon is suspected in segment M6. The environment surrounding the opal codon (position 1052-1054) of segment M6 conforms to that of leaky opal codons described in the literature. PMID- 9367378 TI - Induction of apoptosis by herpes simplex virus type 1. AB - Although herpes simplex virus type 1 (HSV-1) does not induce apoptosis in infected HEp-2 cells, in the presence of cycloheximide infection induced apoptosis with characteristic morphological changes as well as endonucleosomal DNA cleavage. The induction of apoptosis without de novo protein synthesis suggests that a structural protein of the HSV-1 virion is responsible for the observed apoptosis. PMID- 9367377 TI - Resistance to herpes simplex virus type 1 and its latent infection of human T cell lymphotropic virus type I-transformed T cell lines of rabbits. AB - Fourteen T cell lines of rabbits were infected with herpes simplex virus type 1 (HSV-1) and examined for their susceptibility to lytic infection and ability to support virus replication. T cell lines of CD4+ 8- phenotype were more vulnerable to lysis and supported higher levels of virus replication than those of other phenotypes. Cell lines of CD4+ 8+ and CD4- 8+ phenotypes continued to proliferate, while remaining productively infected, for more than a month. These latently infected cell lines could be established by treatment with anti-HSV-1 serum and complement. Viral genes were only partially expressed and the CD8 membrane antigen was down-regulated. Infected cell lines, as well as peripheral blood lymphocytes, were shown to induce meningoencephalitis when inoculated intravenously into syngeneic hosts, suggesting a possible role for infected lymphocytes in HSV-1 transport in vivo. PMID- 9367379 TI - Mutations which alter the DNA binding properties of the herpes simplex virus type 1 transactivating protein Vmw175 also affect its ability to support virus replication. AB - The crucial role of herpes simplex virus type 1 immediate early protein Vmw175 (ICP4) in the regulation of all classes of viral genes has been established by extensive analysis of temperature-sensitive, insertion and deletion mutants. It has long been known that Vmw175 binds to selected DNA sequences, and recent studies have shown that it interacts with components of the basal transcription machinery. However, the role of DNA binding in its mechanism of action has been controversial. Despite the presence of Vmw175 recognition sites at numerous locations throughout the viral genome, it has proved difficult to establish that these sites are important for the activation of early and late promoters. In this study we have analysed the ability of a large number of insertion and single point mutant derivatives of Vmw175 to bind to DNA and to support virus replication. Vmw175 mutants which were unable to bind to DNA were also incapacitated in terms of their ability to activate gene expression in transfection assays and to complement the growth of a Vmw175 deletion mutant virus. These results strongly support the hypothesis that interaction with DNA is an essential feature of the mechanism of action of Vmw175. PMID- 9367380 TI - The product of the US10 gene of herpes simplex virus type 1 is a capsid/tegument associated phosphoprotein which copurifies with the nuclear matrix. AB - We have identified the herpes simplex virus type 1 (HSV-1) US10 gene product using rabbit polyclonal antisera raised against a recombinant 6xHis-US10 fusion protein expressed in Escherichia coli. The antiserum reacted specifically with 34 and 36 kDa proteins in HSV-1 KOS-infected cells as shown by Western blotting and immunoprecipitation experiments. The 36 kDa protein was immunoprecipitated with the US10 antiserum from 32P-labelled lysates of Vero cells infected with HSV-1 KOS, demonstrating that the US10 protein was phosphorylated. Indirect immunofluorescence studies localized the US10 protein mainly to nuclei as large discrete particles at later times post-infection (p.i.), and nuclear fractionation studies revealed that the protein was tightly associated with the nuclear matrix. Moreover, analysis of isolated intracellular capsids showed that both phosphorylated and unphosphorylated forms of the US10 product were also associated with the capsid/tegument. These results indicate that the US10 gene of HSV-1 encodes a capsid/tegument-associated phosphoprotein which copurifies with the nuclear matrix. PMID- 9367381 TI - Mucosal immunization with recombinant adenoviruses: induction of immunity and protection of cotton rats against respiratory bovine herpesvirus type 1 infection. AB - To facilitate the evaluation of vaccines against bovine herpesvirus type 1 (BHV 1), a cotton rat model of intranasal (i.n.) BHV-1 infection was established. Cotton rat lung cells were similar to bovine cells in their ability to support BHV-1 replication in vitro. Furthermore, i.n. inoculation of cotton rats with BHV 1 resulted in pulmonary lesions comparable to BHV-1 infection in cattle. Using this model, the potential of i.n. and gastrointestinal (g.i.) immunization was examined with recombinant human adenoviruses expressing glycoprotein D (gD) of BHV-1 to induce protective immunity against BHV-1. The replication-competent virus (gD-dE3) was more efficient than the replication-defective virus (gD-dE1E3) in inducing gD-specific antibody in the serum and in the respiratory tract. Furthermore, i.n. immunization with gD-dE3 stimulated antigen-specific antibody secreting cells in the lung 12 weeks following immunization. Protection against BHV-1 challenge correlated with gD-specific antibody levels such that i.n. immunization with gD-dE3 conferred complete protection, while g.i. immunization conferred only partial protection of the lungs of most animals against BHV-1 challenge. In comparison, immunization with gD-dE1E3 by either route resulted in only a partial reduction of BHV-1 titre in the respiratory tract. The results obtained demonstrate that mucosal immunization with replication-competent recombinant adenovirus expressing gD of BHV-1 can induce immunity and protection against BHV-1 challenge. PMID- 9367382 TI - Characterization of the assembly and processing of infectious laryngotracheitis virus glycoprotein B. AB - Infectious laryngotracheitis virus (ILTV) is an alpha-herpesvirus that causes severe upper respiratory infections in chickens. Although ten putative ILTV glycoprotein genes have been identified by sequence analysis, no ILTV glycoprotein has been extensively characterized. In order to delineate the synthesis and processing pathway of ILTV glycoprotein B (gB), rabbit polyclonal antibodies were raised against a Cro-gB-beta-galactosidase fusion protein. Through immunoprecipitation analysis of ILTV-infected chicken embryo liver cells it was determined that ILTV gB is initially synthesized as a 110 kDa monomeric precursor protein which rapidly assembles into homodimers composed of 100 kDa subunits. The dimer form of ILTV gB is rapidly cleaved to form two disulphide linked species of 58 kDa. The apparent reduction in mass (from 110 to 100 kDa) of the mature form of gB during processing in the Golgi apparatus appears to be a common feature of avian herpesvirus gB proteins. PMID- 9367383 TI - The human cytomegalovirus UL98 gene encodes the conserved herpesvirus alkaline nuclease. AB - The human cytomegalovirus (HCMV) UL98 gene is predicted to encode a homologue of the conserved herpesvirus alkaline nuclease. To determine if the HCMV UL98 gene product is functionally homologous to other herpesvirus alkaline nucleases, the HCMV UL98 protein was purified and its activity characterized in vitro. Extracts of HCMV-infected cells were fractionated using Q Sepharose, phosphocellulose and native DNA cellulose chromatography. UL98 immunoreactivity copurified with alkaline pH-dependent nuclease activity. The purified protein migrated at its predicted size of approximately 65 kDa in denaturing polyacrylamide gels, and displayed nuclease activity in an activity gel assay. Enzyme activity was characterized by a high pH optimum, an absolute requirement for divalent cation, salt sensitivity, and 5' to 3' exonuclease activity. DNA digestion resulted in 5' monophosphoryl mono- and oligodeoxyribonucleotides. Kinetic analyses revealed a turnover rate of greater than 200 per min, and similar apparent affinity and rate constants on single- and double-stranded DNA. These results indicate that a functional alkaline nuclease activity is conserved among distant members of the herpesvirus family, and are consistent with a highly conserved role in the virus life cycle. PMID- 9367384 TI - Cloning and functional characterization of the origin of lytic-phase DNA replication of rat cytomegalovirus. AB - A cis-acting sequence within the rat cytomegalovirus (RCMV) genome (oriLyt) that directs initiation of lytic-phase DNA replication is identified in this report. RCMV oriLyt was localized within a 4.3 kb NcoI fragment that is situated immediately upstream of the gene encoding the major DNA-binding protein. The activity of oriLyt was investigated in a transient replication assay, in which the ability of plasmid constructs to promote DNA replication was tested. Replication of oriLyt-containing plasmids was autonomous and resulted in the generation of high-molecular-mass concatemers of head-to-tail-linked plasmid oligomers. oriLyt-mediated replication was found to depend on viral DNA polymerase activity supplied by RCMV infection. The sequence required for oriLyt function was found to reside within a 3.3 kb HincII-NcoI fragment. The RCMV oriLyt sequence is highly complex, containing 23 direct repeats (DRs) and 16 inverted repeats (IRs) of lengths greater than 10 bp. Two of the DRs (DR21 and DR22) are exceptionally large, being 80 and 88 bp in length, respectively. In addition, two sequence elements (of 127 and 120 bp) with dyad symmetry were identified within oriLyt. Although the sequence similarity of RCMV oriLyt with its human cytomegalovirus counterpart is limited, there is a striking resemblance in the overall organization of several IRs and DRs within both sequences. PMID- 9367385 TI - Cooperative interaction between Bcl-2 and Epstein-Barr virus latent membrane protein 1 in the growth transformation of human epithelial cells. AB - The Epstein-Barr virus latent membrane protein 1 (LMP-1) is essential for virus induced B cell immortalization and can protect B lymphoma cell lines from apoptosis signals in vitro via induction of cellular Bcl-2 expression. However, we have reported that high-level expression of LMP-1 in epithelial cells (RHEK-1 cells) itself induces apoptosis. This apoptotic event occurs in the absence of detectable Bcl-2 expression in the LMP-1-transfected epithelial cells. In this study, we transfected the bcl-2 gene into the LMP-1-containing cells and examined the effect of Bcl-2 upon LMP-1-mediated apoptosis, and upon the growth phenotype of the transfected cells. The results show that ectopic expression of Bcl-2 specifically blocks apoptotic death induced by LMP-1. This was observed from cell culture viability and from gel electrophoresis and flow cytometric assays of the degree of DNA fragmentation in cultured cells. Furthermore, co-expression of LMP 1 and Bcl-2 in RHEK-1 cells enabled the cells to grow under low-serum conditions and to form colonies in semi-soft agar medium. These results suggest, therefore, that these two proteins play important complementary roles in the process of EBV associated epithelial cell transformation. It appears significant, therefore, that LMP-1 and Bcl-2 are frequently co-expressed in the malignant cells of an EBV positive epithelial tumour, nasopharyngeal carcinoma. PMID- 9367386 TI - BHRF1, a viral homologue of the Bcl-2 oncogene, is conserved at both the sequence and functional level in different Epstein-Barr virus isolates. AB - BHRF 1, a component of the restricted early antigen (EA) complex of the Epstein Barr virus (EBV) lytic cycle, encodes a 17 kDa putative transmembrane protein with both sequence and functional homology to the Bcl-2 proto-oncogene. To determine whether there was any sequence variation over the BHRF1 open reading frame (ORF), 15 EBV isolates from different geographical regions and from both healthy donors and patients with EBV-associated diseases were sequenced. A small number of base changes which resulted in amino acid substitutions in the BHRF1 protein were found relative to the prototype B95.8 EBV sequence and these were predominantly clustered near the amino terminus of the BHRF1 protein outside conserved domains identified in the Bcl-2 homologues. In transient transfection assays none of the mutations in the BHRF1 ORF from eight different EBV isolates had a significant effect on BHRF1 protein localization compared to the B95.8 BHRF1 protein. However, transient expression of the adenovirus 12 19K protein or Bcl-2 resulted in localization patterns distinct from that observed with BHRF1 protein. Whilst all eight EBV isolates and E1B-19K gave comparable levels of protection to the DNA-damaging agent cis-platin, Bcl-2 did not afford significant protection. Thus, despite several amino acid changes in the BHRF1 ORF of some of the EBV isolates studied, the ability of the protein to protect against cis platin induced apoptosis is conserved. The highly conserved nature of BHRF1 amongst different EBV isolates at both the sequence and functional level supports the proposed important role of BHRF1 in delaying cell death, thereby maximizing the production of progeny virus and facilitating the establishment of virus persistence. PMID- 9367387 TI - The role of exogenous p53 and E6 oncoproteins in in vitro transformation by bovine papillomavirus type 4 (BPV-4): significance of the absence of an E6 ORF in the BPV-4 genome. AB - Bovine papillomavirus type 4 (BPV-4) does not possess an E6 ORF. The E6 oncoprotein of human papillomavirus (HPV) binds and degrades the tumour suppressor protein p53, thus contributing to tumour progression. Since BPV-4 lacks E6, it is unknown how the virus evades the tumour suppressor properties of p53 in the induction of tumours of the gastrointestinal tract. Mutations in the p53 gene have been detected both in papillomas and carcinomas, suggesting that p53 dysfunction plays a part in these neoplasias. BPV-4 can transform primary foetal bovine cells (PalFs) in cooperation with an activated ras gene, but the transformed cells are neither immortal nor tumorigenic. Co-transfection with the HPV-16 E6 (16E6) ORF confers immortality but not tumorigenicity. To investigate the role of p53 in BPV-4 cell transformation in vitro, we transfected PalFs and p53-null mouse fibroblasts with BPV-4 DNA in combinations with ras, 16E6 ORF and mutant (V143A) p53 cDNA. Transfection of PalFs with BPV-4 DNA, ras and mutant p53 led to cell immortalization, indicating that 16E6 and mutant p53 are functionally equivalent in conferring immortality. However, co-transfection of PalFs with BPV 4 DNA, ras, and both mutant p53 cDNA and 16E6 ORF resulted in cells which were fully transformed to tumorigenicity. In p53-null mouse fibroblasts, BPV-4 DNA induced transformation by itself, but the transformed cells were incapable of suspension growth. The co-transfection of BPV-4 DNA with 16E6 ORF produced many more transformed colonies and the cells were capable of growing in suspension. In this system, therefore, 16E6 confers anchorage-independence to BPV-4-transformed cells in a p53-independent fashion. PMID- 9367388 TI - Disruption of the human papillomavirus type 16 E2 gene protects cervical carcinoma cells from E2F-induced apoptosis. AB - Human papillomavirus type 16 (HPV-16) is a DNA tumour virus that has been implicated in the development of cervical cancer. In non-transformed HPV-infected cells, the HPV E2 protein regulates transcription of the viral E6 and E7 oncogenes. Malignant transformation is usually accompanied by disruption of the E2 gene and consequent deregulated expression of E6 and E7. Here we show that re introduction of the HPV-16 E2 protein into an HPV-16-transformed cervical carcinoma cell line results in a decrease in growth rate and, in the absence of serum growth factors, cell death via apoptosis. E2 expression increases E6/E7 mRNA levels. This brings about an increase in E7 protein levels, which in turn leads to an increase in free E2F, a condition that has previously been shown to induce apoptotic cell death. Despite the increase in E6 mRNA there is no detectable E6 protein in these cells and E2 expression does not reduce the activity of a p53-responsive promoter. Our data suggest that disruption of the E2 gene produces HPV-transformed cells that are less liable to undergo apoptosis and, therefore, more likely to form cervical tumours. PMID- 9367389 TI - Expression of a functional single chain antibody on the surface of extracellular enveloped vaccinia virus as a step towards selective tumour cell targeting. AB - Recombinant vaccinia virus with tumour cell specificity may provide a versatile tool either for direct lysis of cancer cells or for the targeted transfer of genes encoding immunomodulatory molecules. We report the expression of a single chain antibody on the surface of extracellular enveloped vaccinia virus. The wild type haemagglutinin, an envelope glycoprotein which is not required for viral infection and replication, was replaced by haemagglutinin fusion molecules carrying a single chain antibody directed against the tumour-associated antigen ErbB2. ErbB2 is an epidermal growth factor receptor-related tyrosine kinase overexpressed in a high percentage of human adenocarcinomas. Two fusion proteins carrying the single chain antibody at different NH2-terminal positions were expressed and exposed at the envelope of the corresponding recombinant viruses. The construct containing the antibody at the site of the immunoglobulin-like loop of the haemagglutinin was able to bind solubilized ErbB2. This is the first report of replacement of a vaccinia virus envelope protein by a specific recognition structure and represents a first step towards modifying the host cell tropism of the virus. PMID- 9367390 TI - Characterization of the hepatitis B virus major surface antigen promoter hepatocyte nuclear factor 3 binding site. AB - Transcription of the HBV 2.1 kb RNAs is regulated by the major surface antigen promoter. Previously, transient transfection analysis identified regulatory sequence elements in this promoter located between -189 and +1 which govern the level of transcription from this promoter and appear to bind only ubiquitous transcription factors including NF1, Sp1 and NF-Y. However, in vivo transcription analysis in transgenic mice has demonstrated that the expression of the HBV 2.1 kb RNAs is largely restricted to hepatocytes. In this study, the presence of a functional HNF3 transcription factor binding site located between -231 and -240 in the major surface antigen promoter suggests that the in vivo liver-restricted expression of the 2.1 kb RNAs may be governed by this liver-enriched transcription factor. The identification of a functional HNF3 binding site upstream of the DNA polymerase open reading frame also supports the contention that transient transfection analysis may fail to detect all of the cis-acting regulatory sequence elements involved in modulating the level of transcription from the viral promoters. PMID- 9367391 TI - Presence of integrated DNA sequences of adeno-associated virus type 2 in four cell lines of human embryonic origin. AB - The human helper virus-dependent parvovirus adeno-associated virus (AAV) has been found in human female genital tissues including material from first trimester miscarriage. In the latter case, AAV type 2 (AAV-2) DNA and viral proteins were detected mainly in the trophoblast cell layer of placenta. In this report, we present evidence that AAV DNA is also present in established human trophoblast cell lines (JEG-3, JAr, BeWo) and in the human amnion cell line FL. In cells of these lines, AAV-2 DNA could be detected both by PCR and Southern blot analysis. Restriction enzyme analysis indicated that AAV DNA was integrated into the host cell genome. Although the cell lines supported AAV replication when infected with AAV-2 and adenovirus type 2 (Ad2) as a helper virus, superinfection with Ad2 alone did not induce replication of AAV DNA, i.e. it failed to rescue AAV from its integrated state. This is probably due to rearrangements within the integrated AAV genome. The presence of AAV DNA in cells derived from human embryonic tissue corroborates the suggestion that human embryonic tissue may be one of the targets of AAV infection. PMID- 9367392 TI - The 3' untranslated region of alfalfa mosaic virus RNA3 contains a core promoter for minus-strand RNA synthesis and an enhancer element. AB - The 3' untranslated regions (UTRs) of the three genomic RNAs of alfalfa mosaic virus consist of a 3' homologous sequence of 145 nt and upstream unique sequences 18-34 nt in length. Mutations were made in the 3' UTR of a cDNA clone of RNA3. Point mutations in five AUGC motifs which interfere with specific binding of coat protein to the 3' UTR had no effect on template activity of RNA3 for minus-strand RNA synthesis in vitro by purified viral RNA-dependent RNA polymerase (RdRp). Deletion analysis showed that the 3' homologous sequence of 145 nt was sufficient for a low level of template activity in the in vitro RdRp assay and a similarly low level of RNA3 accumulation in plants. The presence of an additional sequence of nucleotides 145-165 from the 3' end of RNA3 enhanced template recognition by RdRp in vitro and accumulation of RNA3 in vivo to wild-type levels. PMID- 9367393 TI - Expression of the coat protein of potato virus X from a dicistronic mRNA in transgenic potato plants. AB - Transgenic potato plants were generated which express a dicistronic mRNA corresponding to the 8 kDa protein and coat protein (CP) genes of potato virus X (PVX). Northern blot analysis of RNA isolated from these plants indicated that both the 8 kDa protein and the CP are translated from this dicistronic mRNA. Expression of both of these proteins in transgenic plants was demonstrated by Western blot analysis, and suggests that translation of CP takes place either by initiation by internal entry of ribosomes or by a termination/reinitiation mechanism. CP was detected in protoplasts electroporated with RNA transcripts of the dicistronic construct in the presence or absence of a stable hairpin structure at the 5' terminus, suggesting that the former model is more likely. Similar results were obtained when a DNA fragment containing the PVX CP leader sequence was placed between two reporter genes in the transient assay system. These results suggest that potexvirus CP expression may take place from the genomic RNA as well as from the subgenomic RNA. PMID- 9367394 TI - A polydnavirus-encoded protein of an endoparasitoid wasp is an immune suppressor. AB - The molecular mechanism by which polydnaviruses of endoparasitoid wasps disrupt cell-mediated encapsulation reactions of host insects is largely unknown. Here we show that a polydnavirus-encoded protein, produced from baculovirus and plasmid expression vectors, prevents cell surface exposure of lectin-binding sites and microparticle formation during immune stimulation of haemocytes. The inactivation of immune-related cellular processes by this protein was analysed using a specific lectin and annexin V and shown to be virtually identical to polydnavirus mediated effects on haemocytes. Cytochalasin D application has similar effects on haemocytes, suggesting that the immune suppression by the polydnavirus protein is caused by the destabilization of actin filaments. Since the exposure of cell surface glycoproteins and the formation of microparticles are part of an immune response to foreign objects or microorganisms and a prerequisite for cell mediated encapsulation of microorganisms and parasites, the virus-encoded protein may become an important tool for the inactivation of cellular immune reactions in insects and an essential component in understanding immune suppression in parasitized host insects. PMID- 9367396 TI - The ins and outs of glomerular crescent formation. PMID- 9367395 TI - Thalidomide and derivatives: immunological investigations of tumour necrosis factor-alpha (TNF-alpha) inhibition suggest drugs capable of selective gene regulation. PMID- 9367397 TI - Humanized anti-CD4 monoclonal antibody therapy of autoimmune and inflammatory disease. AB - We have investigated the biological and therapeutic properties of a humanized anti-CD4 MoAb, hIgG1-CD4, in patients with refractory psoriasis and rheumatoid arthritis (RA). hIgG1-CD4 is a modulating, non-depleting MoAb, which induced a first-dose reaction in most patients treated. It provided brief symptomatic relief in both conditions, and psoriasis appeared easier to control with conventional agents after MoAb therapy. At the doses used, hIgG1-CD4 did not synergize therapeutically with the panlymphocyte MoAb CAMPATH-1H (C1H) in patients with RA treated sequentially with both agents. There were no serious adverse effects definitely attributable to therapy. Our results are compared with those of other CD4 MoAb studies, and factors influencing the outcome of therapy are discussed. PMID- 9367398 TI - A double-blind, placebo-controlled, crossover therapy study with natural human IL 2 (nhuIL-2) in combination with regular intravenous gammaglobulin (IVIG) infusions in 10 patients with common variable immunodeficiency (CVID). AB - Ten CVID patients with defective IL-2 synthesis in vitro were treated with nhuIL 2 in a placebo-controlled, double blind, crossover therapy study during a period of 12 months. No severe side-effects of nhuIL-2 were recorded. Marginal serum nhuIL-2 levels were measurable in individual patients only during the therapy phase. Serum levels of soluble IL-2 receptors were unaffected by the therapy. nhuIL-2 and placebo groups did not differ significantly with respect to requirement of IVIG substitutions which were performed whenever serum IgG levels dropped below 5 g/l: a total of 53 IVIG infusions (corresponding to 17.6 g IgG/month per patient) was necessary during the placebo phase, and 48 infusions (16.4 g IgG/month per patient) during the nhuIL-2 treatment phase. Thus, nhuIL-2 therapy was ineffective in improving spontaneous IgG synthesis in vivo. Nevertheless, the group of patients receiving nhuIL-2 during the first 6 months of the study exhibited a significant reduction of severe infections (n = 25) during the following 6 months of placebo treatment (n = 7) (P<0.045). The infection score dropped in this group from 181 to 23 (P<0.015). Patients of the second group receiving first placebo and then nhuIL-2 did not experience a significant difference in number and score of infectious episodes: 25 infections were recorded during the first 6 months and 24 during the following 6 months. We suppose that nhuIL-2 therapy of CVID patients reduces susceptibility to severe infections, possibly via the induction of a specific antibody response, which is effective at the earliest 6 months after initiating nhuIL-2 therapy. PMID- 9367399 TI - Defective integration of activating signals derived from the T cell receptor (TCR) and costimulatory molecules in both CD4+ and CD8+ T lymphocytes of common variable immunodeficiency (CVID) patients. AB - CVID is characterized by hypogammaglobulinaemia and impaired antibody production. Previous studies demonstrated defects at the T cell level. In the present study the response of purified CD4+ and CD8+ T lymphocytes to stimulation with anti-TCR monoclonal antibody (the first signal) in combination with anti-CD4 or anti-CD8, anti-CD2 and anti-CD28 MoAbs (the costimulatory signals) was investigated. Both CD4+ and CD8+ T cells from the patients showed significantly reduced IL-2 release following stimulation via TCR and costimulation via CD4 or CD8 and CD2, respectively. However, normal IL-2 production following TCR plus phorbol myristate acetate (PMA) costimulation and normal expression of an early activation marker, CD69, after TCR+CD28 stimulation indicated that TCR was able to transduce a signal. Furthermore, both IL-2 and IL-4 release were impaired in CD4+ lymphocytes following TCR+CD28 stimulation. In addition, stimulation via TCR+CD28 resulted in significantly decreased expression of CD40 ligand in the patients. These results suggest that the integration of activating signals derived from the TCR and costimulatory molecules is defective in CVID patients; the defect is not confined to costimulation via a single molecule, or restricted to cells producing Th1-type cytokines such as IL-2, and is expressed in both CD4+ and CD8+ T cell subsets. PMID- 9367400 TI - Polyclonal T cell elimination by prolonged immunostimulation in an experimental model. AB - An experimental model of immunological deficiency obtained by treating mice for 6 months with serum of human blood drawn from different healthy individuals has been studied. The results show that an alteration of a circulating lymphocyte population with alterations of the ratio CD4+/CD8+ appeared in mice stimulated for a long period with immunogens. Mice treated for 2-4 months showed an increase in B lymphocytes and a decrease in the total number of T lymphocytes, with a decrease in CD4+ lymphocytes and an increase in CD8+ lymphocytes. After 4 months, the CD8+ lymphocyte population started to decrease, with a ratio of CD4+/CD8+ reaching almost 1. In animals treated for 2-3 months, the mean survival time (MST) following experimental infection with Salmonella typhimurium presented a decrease to 5 days, and after 5-6 months of treatment presented a decrease to 3 2.5 days. The bacteraemia was modified in comparison with controls. Prolonged exposure to antigens also induced lymphocyte apoptosis: cells of animals treated for 4-6 months presented increased levels of apoptosis with a percentage that reached 30-35%. A semiquantitative evaluation of the level of heat shock protein (hsp) in splenic lymphocytes showed an increase in the presence of hsp60 and hsp70 in the first 3 months of treatment, which then remained constant for up to 6 months. PMID- 9367401 TI - IgA from HIV+ haemophilic patients triggers intracellular signals coupled to the cholinergic system of the intestine. AB - IgA was obtained from HIV-infected haemophilic patients and the intracellular signals triggered by its reaction with isolated rat intestinal strips were studied. HIV+ IgA stained intestinal microvilli with a granular immunofluorescence pattern and bound to the muscarinic acetylcholine receptor (mAChR), displacing the specific muscarinic cholinergic antagonist QNB in a non competitive manner. It triggered the signals that are the consequence of mAChR stimulation in the intestine. Thus, it decreased cAMP synthesis and increased guanosine 3':5'-cyclic monophosphate (cGMP) formation and phosphoinositide (PI) turnover of the intestine. In addition, it stimulated prostaglandin E2(PGE2) synthesis by intestinal strips. Through its effect on PGE2 synthesis, HIV+ IgA could have a dual action. On the one hand, it could enhance immunosuppression at a local level, favouring pathogen growth and subsequent intestinal dysfunction. On the other hand, PGE2 could directly increase intestinal motility and electrolyte/fluid loss. Both effects could be involved in intestinal damage in AIDS. PMID- 9367403 TI - Biochemical analysis and immunogenicity of Leishmania major amastigote fractions in cutaneous leishmaniasis. AB - Soluble Leishmania antigen (SLA) from both developmental stages of L. major (L. major MRHO/IR/75/ER) were prepared. Three and five subfractions of SLA from amastigote and promastigote were obtained by fast protein liquid chromatography (FPLC), respectively. Biochemical analyses and comparison of amastigote and promastigote SLA were done. The biochemical analyses revealed that the first fraction of L. major amastigote possesses a distinct band on its electrophoretic mobility pattern corresponding to a position of 24 kD, and it has enzymatic activity with characteristics of a cysteine proteinase. The isolated fractions of amastigote were tested for induction of proliferation, interferon-gamma (IFN gamma) and IL-4 production in cultures of peripheral blood mononuclear cells (PBMC) from individuals who had recovered and also chronic patients of cutaneous leishmaniasis caused by L. major. The cells of recovered individuals compared with chronic cases proliferated profoundly in response to the first fraction of amastigote SLA. In all recovered individuals, the IFN-gamma, but not IL-4, was secreted in response to stimulation with the first fraction of amastigote SLA. In chronic cutaneous leishmaniasis, IFN-gamma was infrequently observed in response to stimulation by all three fractions of amastigote SLA, but secretion of IL-4 was observed. These data indicate that first fraction of amastigote SLA is a strong inducer of primed human immune response to L. major, and may have a protective function. PMID- 9367402 TI - Cryptococcus neoformans infection in mice previously infected with LP-BM5 MuLV, the agent of murine AIDS (MAIDS). AB - We studied susceptibility to experimental systemic cryptococcosis in mice previously infected with the retroviral complex LP-BM5 (responsible for murine AIDS). LP-BM5 was inoculated to C57B1/6 mice by intravenous (i.v.) injection 8 weeks before an i.v. challenge with 4 x 10(3) CFU of Cryptococcus neoformans. Uninfected and singly infected mice were used as controls. LP-BM5 infection did not result in a significant increase in fungal burdens in the lungs or brains of co-infected animals compared to mice infected with C. neoformans alone. However, mortality was enhanced in the co-infected animals. The kinetics of splenocyte subsets differed in co-infected mice and LP-BM5-infected mice; the increase in CD4+, CD8+ and Ly5+ cells was only moderate in the former. Cytokine production by concanavalin A (Con A)-stimulated splenocytes from co-infected mice showed a marked decrease in the Th1 response (IFN-gamma, IL-2) and an increase in the Th2 response (IL-4, IL-10). Furthermore, cryptococcosis altered the course of MAIDS, inhibiting splenomegaly. This effect was not related to a decrease in ecotropic virus titres in the spleen or to improved in vitro responsiveness of spleen cells to Con A. The marked decrease in IFN-gamma production in co-infected animals could partly explain the inhibition of LP-BM5-induced splenomegaly. This model of murine retroviral infection does not seem to be suitable for studying cryptococcosis in immunosuppressed animals, but remains valuable for investigating in vivo interactions between two pathogens. PMID- 9367404 TI - Isotypic analysis of maternally transmitted Plasmodium falciparum-specific antibodies in Cameroon, and relationship with risk of P. falciparum infection. AB - In malaria-endemic areas, infants are relatively protected against malaria infection. Such protection is though to be related principally to the transplacental transfer of maternal antibodies. We measured total and Plasmodium falciparum-specific IgG (including subclasses), IgM, and IgE antibodies in 154 paired maternal-cord serum samples from an area of meso- to hyperendemic malaria in South Cameroon. Among peripheral mother blood samples, total IgG and IgM were detected in all samples, IgE in all but two. Plasmodium falciparum-specific IgG were detected in all serum samples, IgM and IgE in > 75% of samples. The prevalence rates of anti-P. falciparum IgG subclasses varied from 75% to 97%. With the exception of P. falciparum-specific IgG, all antibody class and subclass levels were lower in cord blood than in peripheral mother blood. Plasmodium falciparum-specific IgG1 and IgG3 isotypes were transferred to the offspring more often and more efficiently than IgG2 and IgG4. The detection of total and P. falciparum-specific IgM and IgE in some cord serum samples demonstrated that fetuses can mount humoral response against malaria parasites. We also determined whether transplacentally acquired antibodies protect against malaria infection by relating the antibody levels at birth to the risk of acquiring P. falciparum infection during the first 6 months of life. Among various classes and subclasses of P. falciparum-specific antibodies, only IgG2 were related to a decrease in the risk of acquiring a P. falciparum peripheral blood infection from birth to 6 months of age. PMID- 9367405 TI - Circulating antibodies against nicotinic acetylcholine receptors in chagasic patients. AB - Human and experimental Chagas' disease causes peripheral nervous system damage involving neuromuscular transmission alterations at the neuromuscular junction. Additionally, autoantibodies directed to peripheral nerves and sarcolemmal proteins of skeletal muscle have been described. In this work, we analyse the ability of serum immunoglobulin factors associated with human chagasic infection to bind the affinity-purified nicotinic acetylcholine receptor (nAChR) from electric organs of Discopyge tschudii and to identify the receptor subunits involved in the interaction. The frequency of serum anti-nAChR reactivity assayed by dot-blot was higher in seropositive chagasic patients than in uninfected subjects. Purified IgG obtained from chagasic patients immunoprecipitated a significantly higher fraction of the solubilized nAChR than normal IgG. Furthermore, immunoblotting assays indicated that alpha and beta are the main subunits involved in the interaction. Chagasic IgG was able to inhibit the binding of alpha-bungarotoxin to the receptor in a concentration-dependent manner, confirming the contribution of the alpha-subunit in the autoantibody receptor interaction. The presence of anti-nAChR antibodies was detected in 73% of chagasic patients with impairment of neuromuscular transmission in conventional electromyographical studies, indicating a strong association between seropositive reactivity against nAChR and electromyographical abnormalities in chagasic patients. The chronic binding of these autoantibodies to the nAChR could induce a decrease in the population of functional nAChRs at the neuromuscular junction and consequently contribute to the electrophysiological neuromuscular alterations described in the course of chronic Chagas' disease. PMID- 9367407 TI - Local macrophage proliferation in the pathogenesis of glomerular crescent formation in rat anti-glomerular basement membrane (GBM) glomerulonephritis. AB - Glomerular crescent formation is a feature of aggressive forms of glomerulonephritis. The conventional view of crescent formation within Bowman's space involves proliferation of parietal epithelial cells and the recruitment of blood monocytes. However, the potential role of local macrophage proliferation in this process has not been investigated. The current study examines macrophage proliferation within Bowman's space on the basis of expression of the proliferating cell nuclear antigen (PCNA) in a rat model of crescentic glomerulonephritis (accelerated anti-GBM disease). ED1+ macrophages accounted for 42% of cells within early cellular crescents, and 38% of these crescent macrophages were proliferating on the basis of PCNA expression. Macrophages became the dominant cell population in advanced cellular and fibrocellular crescents (64-71%), and there was a significant increase in the level of macrophage proliferation, with 62% and 67% of ED1+ macrophages expressing the PCNA, respectively. This high level of macrophage proliferation was confirmed by incorporation of bromodeoxyuridine and the presence of mitotic figures within crescents. Indeed, macrophages accounted for 73% of all proliferating cells within advanced and fibrocellular crescents. Macrophage proliferation within Bowman's space was a local event, as shown by a lack of proliferating monocytes in the circulation, the presence of mitotic figures within crescents and a reciprocal relationship between the numbers of ED1+ PCNA+ cells within Bowman's space compared with that in the capillary tuft during the progression from early to advanced and fibrocellular crescents. In conclusion, this study has changed the conventional view of the pathogenesis of crescent formation in glomerulonephritis with the demonstration of substantial local macrophage proliferation within Bowman's space. It is proposed that local proliferation is a major mechanism of macrophage accumulation within crescents and plays an important role in the progression of epithelial-dominated early cellular crescents to macrophage-dominated advanced and fibrocellular cellular crescents. PMID- 9367406 TI - IgA nephropathy-specific expression of the IgA Fc receptors (CD89) on blood phagocytic cells. AB - We analysed the biochemical features of receptors for the Fc-region of IgA (Fc alphaR, CD89) on blood monocytes and granulocytes of patients with IgA nephropathy (IgAN). Fc alphaR on monocytes of IgAN were found to have a higher Mr (60-80 kD) than those of control monocytes (50-75 kD) and granulocytes (55-75 kD) in both IgAN and controls as shown by immunoprecipitation analysis. Removal of N linked carbohydrates from Fc alphaR on monocytes of IgAN revealed a 32-36 kD protein core, the Mr of which was still higher than that of controls (28-32 kD). When Fc alphaR transcripts were analysed by reverse-transcription-PCR, only one prominent band was visualized in PCR products from IgAN monocytes. Since the results thus far show that IgAN monocytes express Fc alphaR protein and mRNA differently from granulocytes and control monocytes, PCR products were then cloned and sequenced. The predominant band in PCR products from IgAN monocytes was identical to that of the Fc alphaR a.1 transcript, and an additional 10 transcripts containing five novel transcripts were obtained from granulocytes and control monocytes. In three transcripts, we found an insertion sequence between the S2 and EC1 domains, suggesting the existence of a new exon. These results suggest a predominant usage of Fc alphaR a.1 among various transcripts of Fc alphaR in IgAN monocytes. PMID- 9367409 TI - Specificities of anti-neutrophil autoantibodies in patients with rheumatoid arthritis (RA). AB - The objective of this study was to characterize antigens recognized by neutrophil specific autoantibodies from patients with RA. Sera from 62 RA patients were screened by indirect immunofluorescence (IIF). Positive sera were further tested by ELISAs for antibodies against various granule proteins and by immunoblotting of electrophoretically separated cell, granule or nuclear extracts. Forty-two sera (68%) reacted with ethanol-fixed neutrophils. In the ELISAs 32% of the 28 medium to strongly IIF-positive sera were negative, while 43% were weakly positive for more than one antigen. Immunoblots of whole neutrophils showed IgG reactions at 25-35 kD, in the 55-kD region, at 80 kD, and at 110 kD. Most sera reacted with more than one band. Except for the 55-kD antigen, none of the antigens appeared in lymphocytes. The most notable reactivity in subcellular fractions was with lactoferrin and with bands of 25-35 kD from nuclei. In conclusion, anti-neutrophil autoantibodies from RA patients recognize different antigens in the cytoplasm and in the nucleus. Lactoferrin is one of the common antigens recognized, but also unknown nuclear antigens of 25-35 kD mol. wt are involved. PMID- 9367408 TI - Lung surfactant proteins A and D can inhibit specific IgE binding to the allergens of Aspergillus fumigatus and block allergen-induced histamine release from human basophils. AB - Aspergillus fumigatus is an opportunistic fungal pathogen which, in the immunocompetent host, causes allergic disorders such as allergic rhinitis, allergic sinusitis, hypersensitivity pneumonitis, and allergic bronchopulmonary Aspergillosis (ABPA). In the present study, the interaction of 3-week culture filtrate (3wcf) allergens and various purified glycosylated and non-glycosylated allergens of A. fumigatus with lung surfactant proteins, SP-A and SP-D, was investigated. Purified SP-A and SP-D, isolated from human bronchoalveolar lavage fluid, bound to the 3wcf allergens and purified allergens, gp55 and gp45, in a carbohydrate-specific and calcium-dependent manner. Both SP-A and SP-D did not bind to deglycosylated allergens, suggesting that the ability of SP-A and SP-D to bind certain allergens is mediated through their carbohydrate recognition domains, interacting with the carbohydrate residues on the allergen. Both SP-A and SP-D could inhibit the ability of allergen-specific IgE from Aspergillosis patients to bind these allergens, suggesting that SP-A and SP-D may be involved in the modulation of allergic sensitization and/or development of allergic reactions. The view that SP-A and SP-D play a protective role against airborne allergens is further supported by the demonstration of their ability to inhibit A. fumigatus allergen-induced histamine release from allergic patients' basophils. PMID- 9367410 TI - Recombinant proteinase 3 (Wegener's antigen) expressed in Pichia pastoris is functionally active and is recognized by patient sera. AB - The open reading frame of human proteinase 3 (PR3) without the prepro-peptide was cloned and expressed in Escherichia coli (rcPR3) and in Pichia pastoris (rpPR3). The 6-histidine tagged rpPR3 was efficiently secreted into culture supernatant from which it could be purified by immobilized metal chelate chromatography. Purified rpPR3 migrated as a single 32-kD band on SDS-PAGE and harboured protease activity that could be inhibited with inhibitors specific for serine-proteases. By indirect antigen-capture ELISA using rpPR3, 60% of sera from patients with Wegener's granulomatosis bound to the recombinant product, although it was not recognized in ELISA with directly coated rpPR3. PMID- 9367411 TI - Alteration of DNA methylation levels in MRL lupus mice. AB - Recent reports suggest that DNA methylation is involved in the cause of autoimmune disease. We investigated the alteration of DNA methylation levels in lupus strains of mice, MRL/lpr as a model, which develop an age-dependent lymphadenopathy and autoimmune disease. DNA methylation levels of thymus and axillary lymph nodes in 20-week-old MRL/lpr mice, which are in an autoimmune disease state, were lower than those of 4-week-old MRL/lpr mice with no symptoms as yet. No significant changes were observed in MRL/+ strain mice, which seemed normal at least 20 weeks, while DNA methylation levels in the spleen of both strains of mice increased significantly from the age of 4 to 20 weeks. However, no significant changes of DNA methylation levels in peripheral blood were observed with ageing in MRL strains. Moreover, we clarified that administration of 5-azacytidine had a strong effect on longer survival of MRL/lpr mice and reduced DNA methylation levels in the axillary lymph nodes and spleen. The possible relevance of DNA methylation levels to the progression of autoimmune disease is discussed. PMID- 9367412 TI - Studies of epitope restriction on myeloperoxidase (MPO), an important antigen in systemic vasculitis. AB - Anti-neutrophil cytoplasmic antibodies are important components of the inflammatory response in patients with systemic vasculitis. Their role in the pathogenesis of these conditions remains incompletely defined. Several antigens have been identified, and MPO is one of the most important. To gain more understanding of the immune mechanisms involved, we were keen to see if the antibody response to MPO was restricted, or whether there was a general loss of tolerance to the whole surface of the molecule. To study the epitopes we employed both ELISA and biosensor technology, and were able to demonstrate restriction both in the number and localization of the epitopes being recognized. PMID- 9367413 TI - Antigen-presenting properties of gingival fibroblasts in chronic adult periodontitis. AB - Chronic periodontitis is characterized by dense infiltrations of T lymphocytes in the connective tissue, which consists mainly of gingival fibroblasts. It is becoming increasingly clear that T lymphocytes and gingival fibroblasts are capable of influencing each other. For example, the T cell cytokine interferon gamma (IFN-gamma) is able to induce MHC class II molecules on the surface of several cell types, including gingival fibroblasts. Histological sections of chronically inflamed gingival tissue showed a great number of CD4+ and CD8+ T cells that produced IFN-gamma, and in addition showed abundant expression of MHC class II molecules on gingival fibroblasts. Therefore, we investigated whether these gingival fibroblasts acquire the capacity to carry out MHC class II restricted functions such as antigen presentation to local T cells. In this study, we show that IFN-gamma-treated gingival fibroblasts were able to function as antigen-presenting cells (APC) for superantigen-mediated T cell proliferation. However, these fibroblasts failed to present whole-cell antigens of periodontitis associated bacteria. Moreover, gingival fibroblasts inhibited the presentation of the whole-cell antigens of these bacteria by professional APC. This inhibition could be overcome by the addition of IL-2. These results suggest that gingival fibroblasts play an important role in the local specific immune response in chronic inflammatory periodontal lesions by regulating the response of infiltrating T cells. PMID- 9367414 TI - The relationship between colonization and haemagglutination inhibiting and B cell epitopes of Porphyromonas gingivalis. AB - Passive immunization with the monoclonal antibody 61BG1.3 selectively prevents colonization by Porphyromonas gingivalis in humans (Booth V, Ashley FP, Lehner T. Infect Immun 1996; 64:422-7). The protective MoAb recognizes the beta component of the RI protease of P. gingivalis which is formed by proteolytic processing of a polyprotein precursor termed PrpR1. This subunit is both a haemagglutinin and an antigen which is recognized by sera from patients with periodontitis. In this study the relationship was investigated between a colonization epitope which is recognized by the MoAb 61BG1.3, a haemagglutinating and B cell epitope which are recognized by sera from patients with periodontitis. B cell epitopes were mapped by Western blotting with a series of truncated recombinant polypeptides spanning the adhesion domain within residues 784-1130 of PrpR1 and by ELISA using a panel of synthetic peptides spanning the same sequence. The epitope which is recognized by the protective MoAb was mapped within residues 907-931 of PrpR1, while serum responses of patients were directed predominantly to the adjacent carboxy terminal sequence within residues 934-1042. The haemagglutinating epitope was mapped to residues 1073-1112. In view of our previous findings that the MoAb 61BG1.3 prevents colonization of P. gingivalis in vivo and inhibits haemagglutination, these two epitopes may be in proximity in the native protein. Active or passive immunization strategies which target the protective or haemagglutinating epitopes of the adhesion domain of PrpR1 may provide a means of preventing infection with P. gingivalis. PMID- 9367415 TI - Anti-heat shock protein (hsp)72 antibodies are present in patients with Graves' disease (GD) and in smoking control subjects. AB - Hsp72 is expressed in thyroidal tissue and on retroocular fibroblasts from patients with GD. In this study we investigated whether GD patients have hsp72 antibodies, and if they correlate with disease characteristics. Because smoking is associated with GD and might up-regulate hsp72 expression, we also studied the effect of smoking on hsp antibody levels. Hsp72 IgG antibodies were determined by dot-blotting, using recombinant human stress-inducible hsp72. Dot-blot densities were measured using a videoimaging system in 38 healthy controls, 45 patients with GD, including 34 with varying degrees of ophthalmopathy, and in 13 GD patients before and after treatment of thyrotoxicosis with methimazole. Hsp72 antibodies were detectable more frequently in GD patients (26/45, 58%), than in controls (12/38, 32%; P < 0.02). GD patients had higher antibody levels than controls; mean +/- s.e.m. optical densities: 26.8 +/- 2.6 versus 18.8 +/- 2.4 (P = 0.018). Levels did not correlate with any parameter of disease severity or activity. Hsp72 antibody levels did not change upon reaching euthyroidism. In controls, but not in patients, hsp72 antibodies could be detected more frequently in smokers (6/10, 60%) versus nonsmokers (6/28, 21%; P = 0.024). Patients with GD have higher hsp72 IgG antibody levels than controls, without correlation with any disease characteristic. Among healthy controls, smoking is associated with elevated hsp72 antibodies. This suggests that these antibodies might be a marker for autoimmune susceptibility. PMID- 9367416 TI - Colon carcinoma cell lines stimulate monocytes and lamina propria mononuclear cells to produce IL-10. AB - Cytokines released from tumour cells may have function as signals to neighbouring immune and inflammatory cells. Several studies have shown that the immunoregulatory cytokines IL-10 and transforming growth factor-beta1 (TGF-beta1) as well as prostaglandin-E2 (PGE2) play an important role in tumour-induced immunosuppression. The aim of the study was to investigate the effect of colon carcinoma cell lines on IL-10 production in peripheral monocytes (PBMC) and lamina propria mononuclear cells (LPMC). We examined four colon carcinoma cell lines (HT-29, Caco-2, Colo-320 and HCT-116) and determined their production of TGF-beta1, IL-10 and PGE2. Peripheral monocytes were isolated by density gradient centrifugation and LPMC were isolated from surgical specimens using a collagenase digestion method. Monocytes and LPMC were cultured with colon carcinoma cell conditioned medium or in co-culture with colon carcinoma cells. Supernatants were then determined for the production of IL-10 by ELISA assays. All colon carcinoma cell lines stimulated peripheral monocytes as well as LPMC to produce markedly increased levels of IL-10. Colon cancer cells secreted negligible levels of IL 10, but high amounts of TGF-beta1 and PGE2. Neutralization of TGF-beta1 by administration of anti-TGF-beta as well as neutralization of PGE2 with anti-PGE2 antisera reduced the IL-10 production of monocytes markedly, indicating that tumour cell-derived TGF-beta1 and PGE2 are major factors for IL-10 stimulation. In vitro stimulation of monocytes with TGF-beta1 and PGE2 could confirm that TGF beta1 as well as PGE2 at picogram concentrations were able to prime monocytes for enhanced IL-10 production. Our results demonstrate that colon carcinoma cell lines enhance the ability of monocytes and intestinal macrophages to produce IL 10. The stimulation of monocyte IL-10 by colon cancer cell-derived TGF-beta1 and PGE2 may act as a tumour-protecting mechanism by impairing the activation of anti tumour cytokines. PMID- 9367417 TI - Elevated soluble Fas/APO-1 (CD95) levels in silicosis patients without clinical symptoms of autoimmune diseases or malignant tumours. AB - Soluble Fas (sFas) is produced as translation products of alternative mRNA splicing, and antagonizes the membranous Fas molecule in Fas/Fas ligand interactions. We investigated the serum sFas levels in 64 Japanese silicosis patients with no clinical symptoms of autoimmune diseases or malignant tumours, using ELISA for sFas. The serum sFas levels in the silicosis patients were significantly higher than those in healthy volunteers. Elevated serum sFas levels were also detected in patients with systemic lupus erythematosus but, unexpectedly, no difference was observed in sFas levels between progressive systemic sclerosis patients and healthy volunteers. On the other hand, there was no significant difference in the expression of Fas on peripheral blood lymphocytes between the patients with silicosis and age-matched healthy volunteers. These observations provided the first evidence that serum sFas levels are elevated in silicosis patients without clinical symptoms of autoimmune diseases or malignant tumours. It remains to be clarified whether patients with elevated sFas levels have a tendency to develop autoimmune diseases later, or whether some other distinct factor(s) is necessary to initiate the progression of autoimmune diseases. PMID- 9367418 TI - Quantitative analysis of C4Ab and C4Bb binding to the C3b/C4b receptor (CR1, CD35). AB - Complement-dependent clearance of immune complexes in humans is dependent on the activation and binding of the early components of the classical complement cascade. This prevents immune complex precipitation and promotes binding of the complexes by the C4b/C3b complement receptor CR1 (CD35) found on erythrocytes. The fourth component of human complement is encoded by two closely linked genes within the MHC. These genes give rise to the isotypic forms C4A and C4B, and recent studies suggest that CR1 binds activated C4A (C4Ab) to a greater extent than activated C4B (C4Bb). To study this difference in a more quantitative way the binding reactions between CR1 and C4Ab- and C4Bb-coated immune complexes and between CR1 and soluble dimers of C4Ab (C4Ab2) and C4Bb (C4Bb2) were analysed using the native receptor on human erythrocytes. The binding reaction between immune complexes with equivalent amounts of covalently bound C4Ab or C4Bb and erythrocyte CR1 showed a two-fold higher binding of complexes coated with C4A. Furthermore, erythrocyte CR1 bound C4Ab2 with an apparent four-fold higher affinity (Kd approximately 1.4 x 10(-7) M) than C4Bb2 (Kd approximately 4.8 x 10( 7) M), indicating a preferential binding of CR1 for C4A. PMID- 9367419 TI - Human serum mannose-binding lectin (MBL)-associated serine protease-1 (MASP-1): determination of levels in body fluids and identification of two forms in serum. AB - We developed an ELISA for human serum MASP-1, a C1s-like serine protease which is known to function in C4 and C2 activation. We then determined MASP-1 levels in 1063 sera from normal Japanese subjects ranging in age from 3 to 100 years, as well as in certain body fluids using this assay. Individual serum MASP-1 levels ranged from 1.48 to 12.83 microg/ml, with a normal frequency distribution pattern. The arithmetic mean +/- s.d. of MASP-1 levels in serum was 6.27 +/- 1.85 microg/ml, whereas levels of MASP-1 in cerebrospinal fluid and in urine were almost undetectable. When the mean +/- s.d. of serum MASP-1 was calculated for each age group (10 year range) and values were then compared, the age group consisting of 3-9-year-olds (7.54 +/- 1.39 microg/ml) was found to have the highest value. When MASP-1 was measured in cord blood, it was shown that levels were already as high as those of 3-9-year-olds. The serum MASP-1 level was found to be as strongly dependent on age as is the serum MBL level. MASP-1 and MBL are thought to play an active part in immunity in younger people. It was found that the serum level of MASP-1 was much higher than that of MBL, and the major portion of human serum MASP-1 appeared to exist in the circulation as a form unbound to MBL. PMID- 9367420 TI - Quantification of Bax/Bcl-2 ratios in peripheral blood lymphocytes, monocytes and granulocytes and their relation to susceptibility to anti-Fas (anti-CD95)-induced apoptosis. AB - Neutrophils have the shortest half-life among circulating leucocytes and rapidly undergo apoptosis in vitro. The homologous Bcl-2 and Bax proteins have opposing effects, with Bcl-2 extending cellular survival and Bax promoting cell death following an apoptotic stimulus. We determined Bcl-2 to Bax expression ratios in peripheral blood lymphocytes, monocytes and granulocytes and related them to the susceptibility of these cells to anti-Fas (anti-CD95)-induced apoptosis. Here, we show that Bax/Bcl-2 ratios are high in granulocytes and relatively low in monocytes and lymphocytes. Furthermore, we show a relation between this ratio in the different leucocyte subsets and their susceptibility to anti-Fas-induced apoptosis, with granulocytes showing the highest susceptibility, followed by monocytes and lymphocytes. It is concluded that the balance between Bcl-2 and Bax forms an apoptotic rheostat, which seems to determine sensitivity to apoptosis. PMID- 9367421 TI - IL-7 sensitizes human pre-B cells but not pro-B cells to Fas/APO-1 (CD95) mediated apoptosis. AB - Homeostasis of human B cell development is maintained by a complex network of cytoplasmic and surface expressed molecules. Abnormalities in this process may result in the expansion of malignant B cell precursors in B lineage acute lymphoblastic leukaemia (ALL). ALL cells share surface antigens with normal early precursor B cells. We have studied here the role of Fas/APO-1 (CD95) antigen on leukaemic precursor B cell line growth and survival, and the modulation of its effects by signals involved in normal early B cell development. Four ALL cell lines representative of the early steps of B cell differentiation are shown to express surface Fas/APO-1 (CD95) antigen and to undergo apoptosis in the presence of anti-Fas cross-linking antibodies. This effect is strongly enhanced when pre B, but not pro-B cells, are pretreated with IL-7 but not with IL-2, IL-3, IL-4 or IL-10. Furthermore, pre-B cell death induced by anti-Fas antibodies in combination with IL-7 is increased upon pre-B receptor but not CD19 cross linking. Bcl-2 and Bax protein expression is not influenced by IL-7 or pre-BR stimulation in either pro-B or pre-B cell lines. These results indicate that signals involved in normal early B cell development can modulate the Fas (CD95) mediated apoptosis of leukaemic precursor B cells. PMID- 9367422 TI - Both pituitary and placental growth hormone transcripts are expressed in human peripheral blood mononuclear cells (PBMC). AB - The hGH-V gene codes for a variant of human pituitary growth hormone (hGH-N) named placental growth hormone (hPGH). hPGH shares 93% amino acid identity with hGH-N. Until now the hGH-V gene was considered to be exclusively expressed in human placenta, where it replaces maternal circulating hGH-N at the end of pregnancy. In this study we investigated by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis hGH-N, and hGH-V, gene expression in PBMC in men, women and pregnant women. We have demonstrated that hGH-N and hGH-V transcripts are simultaneously produced by PBMC in both men and women as well as pregnant women. The PBMC of a PIT-1-negative woman expressed only the hGH-V transcript, but not the hGH-N one as expected. In conclusion, hGH-V mRNA is expressed by cells other than the syncytiotrophoblast, is not regulated by PIT-1, and may be involved in immune regulation, as is pituitary GH. PMID- 9367423 TI - Targeted disruption of the mouse homologue of the Drosophila polyhomeotic gene leads to altered anteroposterior patterning and neural crest defects. AB - The rae28 gene is a mouse homologue of the Drosophila polyhomeotic gene (Nomura, M., Takihara, Y. and Shimada, K. (1994) Differentiation 57, 39-50), which is a member of the Polycomb group (Pc-G) of genes (DeCamillis, M., Cheng, N., Pierre, D. and Brock, H.W. (1992) Genes Dev. 6, 223-232). The Pc-G genes are required for the correct expression of the Homeotic complex genes and segment specification during Drosophila embryogenesis and larval development. To study the role of the rae28 gene in mouse development, we generated rae28-deficient mice by gene targeting in embryonic stem cells. The rae28-/- homozygous mice exhibited perinatal lethality, posterior skeletal transformations and defects in neural crest-related tissues, including ocular abnormalities, cleft palate, parathyroid and thymic hypoplasia and cardiac anomalies. The anterior boundaries of Hoxa-3, a 4, a-5, b-3, b-4 and d-4 expression were shifted rostrally in the paraxial mesoderm of the rae28-/- homozygous embryos, and those of Hoxb-3 and b-4 expression were also similarly altered in the rhombomeres and/or pharyngeal arches. These altered Hox codes were presumed to be correlated with the posterior skeletal transformations and neural crest defects observed in the rae28-/- homozygous mice. These results indicate that the rae28 gene is involved in the regulation of Hox gene expression and segment specification during paraxial mesoderm and neural crest development. PMID- 9367424 TI - Differential regulation of gastrulation and neuroectodermal gene expression by Snail in the Drosophila embryo. AB - The initiation of mesoderm differentiation in the Drosophila embryo requires the gene products of twist and snail. In either mutant, the ventral cell invagination during gastrulation is blocked and no mesoderm-derived tissue is formed. One of the functions of Snail is to repress neuroectodermal genes and restrict their expressions to the lateral regions. The derepression of the neuroectodermal genes into the ventral region in snail mutant is a possible cause of defects in gastrulation and in mesoderm differentiation. To investigate such possibility, we analysed a series of snail mutant alleles. We found that different neuroectodermal genes respond differently in various snail mutant background. Due to the differential response of target genes, one of the mutant alleles, V2, that has reduced Snail function showed an intermediate phenotype. In V2 embryos, neuroectodermal genes, such as single-minded and rhomboid, are derepressed while ventral invagination proceeds normally. However, the differentiation of these invaginated cells into mesodermal lineage is disrupted. The results suggest that the establishment of mesodermal cell fate requires the proper restriction of neuroectodermal genes, while the ventral cell movement is independent of the expression patterns of these genes. Together with the data showing that the expression of some ventral genes disappear in snail mutants, we propose that Snail may repress or activate another set of target genes that are required specifically for gastrulation. PMID- 9367425 TI - Role of Hoxa-2 in axon pathfinding and rostral hindbrain patterning. AB - Segmentation plays an important role in neuronal diversification and organisation in the developing hindbrain. For instance, cranial nerve branchiomotor nuclei are organised segmentally within the basal plates of successive pairs of rhombomeres. To reach their targets, motor axons follow highly stereotyped pathways exiting the hindbrain only via specific exit points in the even-numbered rhombomeres. Hox genes are good candidates for controlling this pathfinding, since they are segmentally expressed and involved in rhombomeric patterning. Here we report that in Hoxa-2(-/-) embryos, the segmental identities of rhombomere (r) 2 and r3 are molecularly as well as anatomically altered. Cellular analysis by retrograde dye labelling reveals that r2 and r3 trigeminal motor axons turn caudally and exit the hindbrain from the r4 facial nerve exit point and not from their normal exit point in r2. Furthermore, dorsal r2-r3 patterning is affected, with loss of cochlear nuclei and enlargement of the lateral part of the cerebellum. These results point to a novel role for Hoxa-2 in the control of r2-r3 motor axon guidance, and also suggest that its absence may lead to homeotic changes in the alar plates of these rhombomeres. PMID- 9367426 TI - The roles of hedgehog and engrailed in patterning adult abdominal segments of Drosophila. AB - We present evidence that hedgehog (hh) protein secreted by posterior compartment cells plays a key role in patterning the posterior portion of the anterior compartment in adult abdominal segments. Loss of function of hh in the hh(ts2) mutant causes the loss of posterior tergite characteristics in the anterior compartment, whereas ectopic expression driven by hs-hh or the gain-of-function allele hh(Mir) causes transformation of anterior structures toward the posterior. FLP-out hh-expressing clones in the anterior compartment induce surrounding wild type cells to produce posterior tergite structures, establishing that hh functions nonautonomously. The effects of pulses of ectopic expression driven by hs-hh indicate that bristle type and pigmentation are patterned by hh at widely different times in pupal development. We also present evidence that the primary polarization of abdominal segments is symmetric. This symmetry is strikingly revealed by ectopic expression of engrailed (en). As expected, this transforms anterior compartment cells to posterior compartment identity. In addition, however, ectopic en expression causes an autonomous reversal of polarity in the anterior portion of the anterior compartment, but not the posterior portion. By determining the position of polarity reversal within en-expressing clones, we were able to define a cryptic line of symmetry that lies within the pigment band of the normal tergite. This line appears to be retained in hh(ts2) mutants raised at the restrictive temperature, suggesting it is not established by hh signaling. We argue that the primary role of hh in controlling polarity is to cause anterior compartment cells to reverse their interpretation of an underlying symmetric polarization. Consistent with this, we find that strong ectopic expression of hh causes mirror-symmetric double posterior patterning, whereas hh loss of function can cause mirror-symmetric double anterior patterning. PMID- 9367427 TI - Control of cell fate and polarity in the adult abdominal segments of Drosophila by optomotor-blind. AB - In an accompanying report (Kopp, A., Muskavitch, M. A. T. and Duncan, I. (1997) Development 124, 3703-3714), we show that Hh protein secreted by posterior compartment cells patterns the posterior portion of the anterior compartment in adult abdominal segments. Here we show that this function of hh is mediated by optomotor-blind (omb). omb- mutants mimic the effects of loss-of-function alleles of hh: structures from the posterior of the anterior compartment are lost, and often this region develops as a mirror image of the anterior portion. Structures from the anterior part of the posterior compartment are also lost. In the pupa, omb expression in abdominal histoblasts is highest at or near the compartment boundary, and decreases in a shallow gradient toward the anterior. This gradient is due to activation of omb by Hh secreted by posterior compartment cells. In contrast to imaginal discs, this Hh signaling is not mediated by dpp or wg. We describe several gain-of-function alleles that cause ectopic expression of omb in the anterior of the segment. Most of these cause the anterior region to develop with posterior characteristics without affecting polarity. However, an allele that drives high level ubiquitous expression of omb (QdFab) causes the anterior tergite to develop as a mirror-image duplication of the posterior tergite, a pattern opposite to that seen in omb- mutants. Ubiquitous expression of hh causes similar double-posterior patterning. We find that omb- alleles suppress this effect of ectopic hh expression and that posterior patterning becomes independent of hh in the QdFab mutant. These observations indicate that omb is the primary target of hh signaling in the adult abdomen. However, it is clear that other targets exist. One of these is likely Scruffy, a novel gene that we describe, which acts in parallel to omb. To explain the effects of omb alleles, we propose that both anterior and posterior compartments in the abdomen are polarized by underlying symmetric gradients of unknown origin. We suggest that omb has two functions. First, it specifies the development of appropriate structures both anterior and posterior to the compartment boundary. Second, it causes cells to reverse their interpretation of polarity specified by the underlying symmetric gradients. PMID- 9367428 TI - Wingless signaling generates pattern through two distinct mechanisms. AB - wingless (wg) and its vertebrate homologues, the Wnt genes, play critical roles in the generation of embryonic pattern. In the developing Drosophila epidermis, wg is expressed in a single row of cells in each segment, but it influences cell identities in all rows of epidermal cells in the 10- to 12-cell-wide segment. Wg signaling promotes specification of two distinct aspects of the wild-type intrasegmental pattern: the diversity of denticle types present in the anterior denticle belt and the smooth or naked cuticle constituting the posterior surface of the segment. We have manipulated the expression of wild-type and mutant wg transgenes to explore the mechanism by which a single secreted signaling molecule can promote these distinctly different cell fates. We present evidence consistent with the idea that naked cuticle cell fate is specified by a cellular pathway distinct from the denticle diversity-generating pathway. Since these pathways are differentially activated by mutant Wg ligands, we propose that at least two discrete classes of receptor for Wg may exist, each transducing a different cellular response. We also find that broad Wg protein distribution across many cell diameters is required for the generation of denticle diversity, suggesting that intercellular transport of the Wg protein is an essential feature of pattern formation within the epidermal epithelium. Finally, we demonstrate that an 85 amino acid region not conserved in vertebrate Wnts is dispensable for Wg function and we discuss structural features of the Wingless protein required for its distinct biological activities. PMID- 9367429 TI - Ectopic expression of the maize kn1 gene phenocopies the Hooded mutant of barley. AB - The homeobox gene, knotted1, (kn1) is expressed in shoot meristems and is required for maintaining indeterminacy and preventing cellular differentiation. Awns, extensions of the bract-like lemma found in all grass inflorescences, are normally determinate structures. We show that ectopic expression of kn1 in the barley awn is sufficient to direct the development of ectopic meristems, forming inflorescence-like structures. This homeotic transformation is similar to the phenotype produced by misexpression of the barley hvknox3 gene, associated with the dominant Hooded mutant (Muller, K. J., Romano, N., Gerstner, O., Garcia Maroto, F., Pozzi, C., Salamini, F. and Rohde, W. (1995) Nature 374, 727-730). We suggest that the inverse polarity of the ectopic flowers seen in Hooded and transgenic kn1 plants results from the transformation of the awn into reiterative inflorescence axes. We observed that the protein and mRNA localization of the transgene, driven by a constitutive promoter, is similar to the expression pattern of hvknox3 in awns of Hooded mutants, suggesting posttranscriptional regulation. PMID- 9367430 TI - Integration of the head and trunk segmentation systems controls cephalic furrow formation in Drosophila. AB - Genetic and molecular analyses of patterning of the Drosophila embryo have shown that the process of segmentation of the head is fundamentally different from the process of segmentation of the trunk. The cephalic furrow (CF), one of the first morphological manifestations of the patterning process, forms at the juxtaposition of these two patterning systems. We report here that the initial step in CF formation is a change in shape and apical positioning of a single row of cells. The anteroposterior position of these initiator cells may be defined by the overlapping expression of the head gap gene buttonhead (btd) and the primary pair-rule gene even-skipped (eve). Re-examination of the btd and eve phenotypes in live embryos indicated that both genes are required for CF formation. Further, Eve expression in initiator cells was found to be dependent upon btd activity. The control of eve expression by btd in these cells is the first indication of a new level of integrated regulation that interfaces the head and trunk segmentation systems. In conjunction with previous data on the btd and eve embryonic phenotypes, our results suggest that interaction between these two genes both controls initiation of a specific morphogenetic movement that separates two morphogenetic fields and contributes to patterning the hinge region that demarcates the procephalon from the segmented germ band. PMID- 9367431 TI - Cardiomyocyte differentiation by GATA-4-deficient embryonic stem cells. AB - In situ hybridization studies, promoter analyses and antisense RNA experiments have implicated transcription factor GATA-4 in the regulation of cardiomyocyte differentiation. In this study, we utilized Gata4-/- embryonic stem (ES) cells to determine whether this transcription factor is essential for cardiomyocyte lineage commitment. First, we assessed the ability of Gata4-/- ES cells form cardiomyocytes during in vitro differentiation of embryoid bodies. Contracting cardiomyocytes were seen in both wild-type and Gata4-/- embryoid bodies, although cardiomyocytes were observed more often in wild type than in mutant embryoid bodies. Electron microscopy of cardiomyocytes in the Gata4-/- embryoid bodies revealed the presence of sarcomeres and junctional complexes, while immunofluorescence confirmed the presence of cardiac myosin. To assess the capacity of Gata4-/- ES cells to differentiate into cardiomyocytes in vivo, we prepared and analyzed chimeric mice. Gata4-/- ES cells were injected into 8-cell stage embryos derived from ROSA26 mice, a transgenic line that expresses beta galactosidase in all cell types. Chimeric embryos were stained with X-gal to discriminate ES cell- and host-derived tissue. Gata4-/- ES cells contributed to endocardium, myocardium and epicardium. In situ hybridization showed that myocardium derived from Gata4-/- ES cells expressed several cardiac-specific transcripts, including cardiac alpha-myosin heavy chain, troponin C, myosin light chain-2v, Nkx-2.5/Csx, dHAND, eHAND and GATA-6. Taken together these results indicate that GATA-4 is not essential for terminal differentiation of cardiomyocytes and suggest that additional GATA-binding proteins known to be in cardiac tissue, such as GATA-5 or GATA-6, may compensate for a lack of GATA-4. PMID- 9367433 TI - Cell morphogenesis of trichomes in Arabidopsis: differential control of primary and secondary branching by branch initiation regulators and cell growth. AB - Cell morphogenesis, i.e. the acquisition of a particular cell shape, can be examined genetically in the three-branched trichomes that differentiate from single epidermal cells on the leaves of Arabidopsis thaliana. In normal development, the growing trichome cell undergoes two successive branching events, resulting in a proximal side stem and a distal main stem which subsequently splits in two branches. Using new and previously described trichome mutants, we have analyzed the branching pattern in single and double mutants affecting branch number or cell size in order to determine underlying mechanisms. Our results suggest that primary branching is genetically distinct from subsequent branching events and that the latter, secondary events are initiated in response to positive and negative regulators of branching as well as subject to control by cell growth. We propose a model of how trichome cell morphogenesis is regulated during normal development. PMID- 9367432 TI - Pax6-dependent regulation of adhesive patterning, R-cadherin expression and boundary formation in developing forebrain. AB - Mutations in the gene for the transcription factor, Pax6, induce marked developmental abnormalities in the CNS and the eye, but the cellular mechanisms that underlie the phenotype are unknown. We have examined the adhesive properties of cells from the developing forebrain in Small eye, the Pax6 mutant mouse. We have found that the segregation normally observed in aggregates of cortical and striatal cells in an in vitro assay is lost in Small eye. This correlates with an alteration of in vivo expression of the homophilic adhesion molecule, R-cadherin. Moreover, the boundary between cortical and striatal regions of the telencephalon is dramatically altered in Small eye: radial glial fascicles do not form at the border, and the normal expression of R-cadherin and tenascin-C at the border is lost. These data suggest a link between the transcription factor, Pax6, R cadherin expression, cellular adhesion and boundary formation between developing forebrain regions. PMID- 9367434 TI - Argos and Spitz group genes function to regulate midline glial cell number in Drosophila embryos. AB - The midline glia of the Drosophila embryonic nerve cord undergo a reduction in cell number after facilitating commissural tract morphogenesis. The numbers of midline glia entering apoptosis at this stage can be increased by a loss or reduction of function in genes of the spitz group or Drosophila EGF receptor (DER) pathway. Argos, a secreted molecule with an atypical EGF motif, is postulated to function as a DER antagonist. In this work, we assess the role of argos in the determination of midline glia cell number. Although all midline glia express DER, argos expression is restricted to the midline glia which do not enter apoptosis. Fewer midline glia enter apoptosis in embryos lacking argos function. Ectopic expression of argos is sufficient to remove all DER-expressing midline glia from the nerve cord, even those that already express argos. DER expression is not terminated in the midline glia after spitz group signaling triggers changes in gene expression. It is therefore likely that an attenuation of DER signaling by Argos is integrated with the augmentation of DER signaling by Spitz throughout the period of reduction of midline glia number. We suggest that signaling by Spitz but not Argos is restricted to adhesive junctions. In this manner, midline glia not forming signaling junctions remain sensitive to juxtacrine Argos signaling, while an autocrine Argos signal is excluded by the adhesive junction. PMID- 9367435 TI - The ALK-2 and ALK-4 activin receptors transduce distinct mesoderm-inducing signals during early Xenopus development but do not co-operate to establish thresholds. AB - The TGFbeta family member activin induces different mesodermal cell types in a dose-dependent fashion in the Xenopus animal cap assay. High concentrations of activin induce dorsal and anterior cell types such as notochord and muscle, while low concentrations induce ventral and posterior tissues such as mesenchyme and mesothelium. In this paper we investigate whether this threshold phenomenon involves the differential effects of the two type I activin receptors ALK-2 and ALK-4. Injection of RNA encoding constitutively active forms of the receptors (here designated ALK-2* and ALK-4*) reveals that ALK-4* strongly induces the more posterior mesodermal marker Xbra and the dorsoanterior marker goosecoid in animal cap explants. Maximal levels of Xbra expression are attained using lower concentrations of RNA than are required for the strongest activation of goosecoid, and at the highest doses of ALK-4*, levels of Xbra transcription decrease, as is seen with high concentrations of activin. By contrast, the ALK-2* receptor activates Xbra but fails to induce goosecoid to significant levels. Analysis at later stages reveals that ALK-4* signalling induces the formation of a variety of mesodermal derivatives, including dorsal cell types, in a dose dependent fashion, and that high levels also induce endoderm. By contrast, the ALK-2* receptor induces only ventral mesodermal markers. Consistent with these observations, ALK-4* is capable of inducing a secondary axis when injected into the ventral side of 32-cell stage embryos whilst ALK-2* cannot. Co-injection of RNAs encoding constitutively active forms of both receptors reveals that ventralising signals from ALK-2* antagonise the dorsal mesoderm-inducing signal derived from ALK-4*, suggesting that the two receptors use distinct and interfering signalling pathways. Together, these results show that although ALK 2* and ALK-4* transduce distinct signals, the threshold responses characteristic of activin cannot be due to interactions between these two pathways; rather, thresholds can be established by ALK-4* alone. Furthermore, the effects of ALK-2* signalling are at odds with it behaving as an activin receptor in the early Xenopus embryo. PMID- 9367436 TI - Patterning of the embryo along the anterior-posterior axis: the role of the caudal genes. AB - Patterning along the anterior-posterior axis takes place during gastrulation and early neurulation. Homeobox genes like Otx-2 and members of the Hox family have been implicated in this process. The caudal genes in Drosophila and C. elegans have been shown to determine posterior fates. In vertebrates, the caudal genes begin their expression during gastrulation and they take up a posterior position. By injecting sense and antisense RNA of the Xenopus caudal gene Xcad-2, we have studied a number of regulatory interactions among homeobox genes along the anterior-posterior axis. Initially, the Xcad-2 and Otx-2 genes are mutually repressed and, by late gastrulation, they mark the posterior- or anterior-most domains of the embryo, respectively. During late gastrulation and neurulation, Xcad-2 plays an additional regulatory function in relation to the Hox genes. Hox genes normally expressed anteriorly are repressed by Xcad-2 overexpression while those normally expressed posteriorly exhibit more anterior expression. The results show that the caudal genes are part of a posterior determining network which during early gastrulation functions in the subdivision of the embryo into anterior head and trunk domains. Later in gastrulation and neurulation these genes play a role in the patterning of the trunk region. PMID- 9367437 TI - The maternal par genes and the segregation of cell fate specification activities in early Caenorhabditis elegans embryos. AB - After fertilization in C. elegans, activities encoded by the maternally expressed par genes appear to establish cellular and embryonic polarity. Loss-of-function mutations in the par genes disrupt anterior-posterior (a-p) asymmetries in early embryos and result in highly abnormal patterns of cell fate. Little is known about how the early asymmetry defects are related to the cell fate patterning defects in par mutant embryos, or about how the par gene products affect the localization and activities of developmental regulators known to specify the cell fate patterns made by individual blastomeres. Examples of such regulators of blastomere identity include the maternal proteins MEX-3 and GLP-1, expressed at high levels anteriorly, and SKN-1 and PAL-1, expressed at high levels posteriorly in early embryos. To better define par gene functions, we examined the expression patterns of MEX-3, PAL-1 and SKN-1, and we analyzed mex-3, pal-1, skn-1 and glp-1 activities in par mutant embryos. We have found that mutational inactivation of each par gene results in a unique phenotype, but in no case do we observe a complete loss of a-p asymmetry. We conclude that no one par gene is required for all a-p asymmetry and we suggest that, in some cases, the par genes act independently of each other to control cell fate patterning and polarity. Finally, we discuss the implications of our findings for understanding how the initial establishment of polarity in the zygote by the par gene products leads to the proper localization of more specifically acting regulators of blastomere identity. PMID- 9367438 TI - Torso signalling regulates terminal patterning in Drosophila by antagonising Groucho-mediated repression. AB - Patterning of the non-segmental termini of the Drosophila embryo depends on signalling via the Torso receptor tyrosine kinase (RTK). Activation of Torso at the poles of the embryo triggers restricted expression of the zygotic gap genes tailless (tll) and huckebein (hkb). In this paper, we show that the Groucho (Gro) corepressor acts in this process to confine terminal gap gene expression to the embryonic termini. Embryos lacking maternal gro activity display ectopic tll and hkb transcription; the former leads, in turn, to lack of abdominal expression of the Kruppel and knirps gap genes. We show that torso signalling permits terminal gap gene expression by antagonising Gro-mediated repression. Thus, the corepressor Gro is employed in diverse developmental contexts and, probably, by a variety of DNA-binding repressors. PMID- 9367439 TI - LEAFY expression and flower initiation in Arabidopsis. AB - During the initial vegetative phase, the Arabidopsis shoot meristem produces leaves with associated lateral shoots at its flanks, while the later reproductive phase is characterized by the formation of flowers. The LEAFY gene is an important element of the transition from the vegetative to the reproductive phase, as LEAFY is both necessary and sufficient for the initiation of individual flowers. We have analyzed in detail the expression of LEAFY during the plant life cycle, and found that LEAFY is extensively expressed during the vegetative phase. In long days, Arabidopsis plants flower soon after germination, and this is paralleled by rapid upregulation of LEAFY. In short days, Arabidopsis plants flower several weeks later than in long days, but LEAFY expression increases gradually before flowering commences. Application of the plant hormone gibberellin, which hastens flowering in short days, enhances the gradual change in LEAFY expression observed in short days. Changes in LEAFY expression before the transition to flowering suggest that the time point of this transition is at least partly controlled by the levels of LEAFY activity that are prevalent at a given time of the life cycle. This assumption is borne out by the finding that increasing the copy number of endogenous LEAFY reduces the number of leaves produced before the first flower is formed. Thus, LEAFY combines properties of flowering-time and flower-meristem-identity genes, indicating that LEAFY is a direct link between the global process of floral induction and the regional events associated with the initiation of individual flowers. PMID- 9367440 TI - Floral determination and expression of floral regulatory genes in Arabidopsis. AB - The expression of the floral regulators LEAFY, APETALA1 and AGAMOUS-LIKE8 was examined during light treatments that induced flowering in Arabidopsis, and was compared to time points at which floral determination occurred. Extension of an 8 hour day by either continuous red- or far-red-enriched light induced LEAFY and AGAMOUS-LIKE8 expression within 4 hours. The 4 hours of additional light was sufficient for floral determination only in the far-red-enriched conditions, while 12-16 hours of additional light was required for floral determination in the red-enriched conditions. These results indicate that the induction of floral regulatory genes and induction of flower formation can be uncoupled under certain circumstances. Expression of LEAFY and AGAMOUS-LIKE8 in the shoot apex at the time of floral determination is also consistent with genetic data indicating that these genes are involved in the first steps of the transition from vegetative to reproductive development. In contrast to LEAFY and AGAMOUS-LIKE8, APETALA1 expression was first observed 16 hours after the start of photoinduction. Since this time point was always after floral determination, APETALA1 is an indicator of floral determination. PMID- 9367441 TI - An activity-dependent network of interactions links the Rel protein Dorsal with its cytoplasmic regulators. AB - A signaling pathway active on the ventral side of the Drosophila embryo defines dorsoventral polarity. A cell surface signal relayed by Toll, Tube and Pelle releases the Rel-related protein Dorsal from its cytoplasmic inhibitor Cactus; free Dorsal translocates into nuclei and directs expression of ventral fates. Using the yeast two-hybrid system and immunoprecipitation experiments, we define scaffolding and anchoring interactions among the pathway components. We show that Dorsal binds specifically to Tube, Pelle and Cactus, and that the protein kinase activity of Pelle differentially regulates its interactions with Dorsal and Tube. We also identify Drosophila Filamin as a potential adaptor linking the interaction network, via Tube, to the transmembrane receptor Toll. PMID- 9367442 TI - Maternal control of a zygotic patterning gene in Caenorhabditis elegans. AB - The transition from maternal to zygotic gene control is a key process in embryogenesis. Although many maternal effect genes have been studied in the C. elegans embryo, how their activities lead to the positional expression of zygotic patterning genes has not yet been established. Evidence is presented showing that expression of the zygotic patterning gene vab-7 does not depend on cell position or cell contacts, but rather on the production of a C blastomere. Furthermore, pal-1, a caudal homologue with maternal product necessary for the proper development of the C blastomere, is both necessary and sufficient for vab-7 expression. This provides a link between maternal gene activity and zygotic patterning gene expression in C. elegans. The results suggest that zygotic patterning genes might be generally controlled at the level of blastomere fate and not by position. PMID- 9367443 TI - Ectopic activation of torpedo/Egfr, a Drosophila receptor tyrosine kinase, dorsalizes both the eggshell and the embryo. AB - The Drosophila gene torpedo/Egfr (top/Egfr) encodes a homolog of the vertebrate Epidermal Growth Factor receptor. This receptor is required several times during the life cycle of the fly for the transmisson of developmental cues. During oogenesis, Top/Egfr activation is required for the establishment of the dorsal/ventral axis of the egg and the embryo. To examine how ectopic Top/Egfr activation affects cell fate determination, we constructed an activated version of the protein. Expression of this activated form (lambda top) in the follicle cells of the ovary induces dorsal cell fates in both the follicular epithelium and the embryo. Different levels of expression resulted in different dorsal follicle cell fates. These dorsal cell fates were expanded in the anterior, but not the posterior, of the egg, even in cases where all the follicle cells covering the oocyte expressed lambda top. The expression of genes known to respond to top/Egfr activation, argos (aos), kekkon1 (kek 1) and rhomboid (rho), was also expanded in the presence of the lambda top construct. When lambda top was expressed in all the follicle cells covering the oocyte, kek 1 and argos expression was induced in follicle cells all along the anterior/posterior axis of the egg chamber. In contrast, rho RNA expression was only activated in the anterior of the egg chamber. These data indicate that the response to Top/Egfr signaling is regulated by an anterior/posterior prepattern in the follicle cells. Expression of lambda top in the entire follicular epithelium resulted in an embryo dorsalized along the entire anterior/posterior axis. Expression of lambda top in anterior or posterior subpopulations of follicle cells resulted in regionally autonomous dorsalization of the embryos. This result indicates that subpopulations of follicle cells along the anterior/posterior axis can respond to Top/Egfr activation independently of one another. PMID- 9367444 TI - The Drosophila neurogenic gene big brain, which encodes a membrane-associated protein, acts cell autonomously and can act synergistically with Notch and Delta. AB - In the developing nervous system of Drosophila, cells in each proneural cluster choose between neural and epidermal cell fates. The neurogenic genes mediate the cell-cell communication process whereby one cell adopts the neural cell fate and prevents other cells in the cluster from becoming neural. In the absence of neurogenic gene function, most, if not all of the cells become neural. big brain is a neurogenic gene that encodes a protein with sequence similarity to known channel proteins. It is unique among the neurogenic genes in that previous genetic studies have not revealed any interaction between big brain and the other neurogenic genes. Furthermore, the neural hypertrophy in big brain mutant embryos is less severe than that in embryos mutant for other neurogenic genes. In this paper, we show by antibody staining that bib is expressed in tissues that give rise to neural precursors and in other tissues that are affected by loss of neurogenic gene function. By immunoelectron microscopy, we found that bib is associated with the plasma membrane and concentrated in apical adherens junctions as well as in small cytoplasmic vesicles. Using mosaic analysis in the adult, we demonstrate that big brain activity is required autonomously in epidermal precursors to prevent neural development. Finally, we demonstrate that ectopically expressed big brain acts synergistically with ectopically expressed Delta and Notch, providing the first evidence that big brain may function by augmenting the activity of the Delta-Notch pathway. These results are consistent with bib acting as a channel protein in proneural cluster cells that adopt the epidermal cell fate, and serving a necessary function in the response of these cells to the lateral inhibition signal. PMID- 9367445 TI - Control of dorsoventral pattern in the chick paraxial mesoderm. AB - The most profound feature of the mature vertebrate somite is its organisation into dorsal dermomyotome, intermediate myotome and ventral sclerotome. We analysed the role of potential signalling structures in this dorsoventral pattern by ablating them or transplanting them to ectopic locations in chick embryos. Our data suggest that the somite represents a naive tissue, entirely depending on external cues for its dorsoventral organisation. Dorsalisation by signals from dorsal neural tube and surface ectoderm stimulates the development of the dermomyotome. Likewise, signals from notochord and floor plate ventralise the somite, at high levels overriding any dorsal information and inducing the sclerotome. The dorsalising factors and lower levels of the ventralising factors act in concert to induce the myotome. Finally, the paraxial mesoderm intrinsically controls its competence to respond to the external inducers. PMID- 9367447 TI - The weight of our heritage. PMID- 9367446 TI - Integrins mediate adhesion to agrin and modulate agrin signaling. AB - Agrin, a basal lamina-associated proteoglycan, is a crucial nerve-derived organizer of postsynaptic differentiation at the skeletal neuromuscular junction. Because integrins serve as cellular receptors for many basal lamina components, we asked whether agrin interacts with integrins. Agrin-induced aggregation of acetylcholine receptors on cultured myotubes was completely blocked by antibodies to the beta1 integrin subunit and partially blocked by antibodies to the alpha(v) integrin subunit. Agrin-induced clustering was also inhibited by antisense oligonucleotides to alpha(v) and a peptide that blocks the alpha(v) binding site. Non-muscle cells that expressed alpha(v) and beta1 integrin subunits adhered to immobilized agrin, and this adhesion was blocked by anti-alpha(v) and anti-beta1 antibodies. Integrin alpha(v)-negative cells that did not adhere to agrin were rendered adherent by introduction of alpha(v). Together, these results implicate integrins, including alpha(v)beta1, as components or modulators of agrin's signal transduction pathway. PMID- 9367448 TI - What initiates the systemic inflammatory response in cardiac surgery patients? PMID- 9367449 TI - Host defense response and outcome in ARDS. PMID- 9367450 TI - Of emperors, emboli, and echocardiography. PMID- 9367451 TI - Aspergillus airway colonization and invasive disease after lung transplantation. AB - BACKGROUND: Invasive Aspergillus is an important cause of morbidity and mortality among lung transplant recipients. The diagnosis can be difficult and treatment is often unsuccessful so many centers preemptively treat all Aspergillus airway isolates to prevent invasive disease. This approach is untested as little is known about the relationship between Aspergillus airway colonization and invasive disease. This study was undertaken to evaluate the incidence of Aspergillus airway colonization after lung transplantation and the risk of invasive disease after colonization. DESIGN: All cultures and histologic specimens obtained from a consecutive series of 151 lung transplant cases were reviewed for the presence of Aspergillus and compared with clinical data. RESULTS: Aspergillus was isolated from the airway in 69 (46%) of 151 transplant recipients. Invasive disease occurred in five cases and was uniformly fatal, accounting for 13% of all posttransplant deaths. Results of cytologic examination of BAL fluid were normal in all cases of invasive disease and cultures were positive in only one of five patients prior to invasion. Invasive disease occurred exclusively in patients who died or were colonized with Aspergillus fumigatus within the first 6 months posttransplant. Patients growing A. fumigatus from the airway during the first 6 months were 11 times more likely to develop invasive disease relative to those not colonized. CONCLUSION: Aspergillus airway colonization after lung transplantation is common and in most cases, transient. In contrast, invasive Aspergillus disease is less common, but fatal. Bronchoscopy with cytologic examination and fungal culture are not sensitive or timely predictors of invasive disease. Invasive Aspergillus occurred only in patients initially colonized with A. fumigatus within the first 6 months posttransplant. A trial of empiric anti Aspergillus therapy limited to the first 6 months posttransplant may be warranted. PMID- 9367452 TI - Quality of life in female lung transplant candidates and recipients. AB - OBJECTIVE: Quality of life (QOL) studies of lung transplant recipients indicate that there are improvements following transplantation. More recently, there has been some suggestion that certain QOL issues are different for men and women. The purpose of the present study was to examine changes in QOL, body satisfaction, and sexual functioning in women lung transplant recipients. STUDY POPULATION: Seven prelung transplant (PRE) and 34 postlung transplant (POST) women. MAIN OUTCOME MEASURES: The RAND-36 Health Survey, Body Cathexis Scale, Derogatis Sexual Functioning Inventory, Hospital Depression and Anxiety Scale, Rosenberg Self-Esteem Scale, and an open-ended questionnaire. RESULTS: Higher scores were found in the POST group with respect to general health and role limitations due to physical health. We were unable to detect significant differences between the groups with respect to emotional well-being, role limitations due to emotional health, and social functioning. There were significant differences between the PRE and the POST body satisfaction scores. Although there was no significant difference in overall sexual functioning, recipients in the PRE group reported higher sex drive. Eleven of the POST recipients (52%) scored below the 10th percentile in overall sexual functioning. CONCLUSIONS: Overall QOL improves following lung transplantation; however, the lack of differences in many domains of QOL raises the concern that women lung transplant recipients may continue to have significant impairments, including those regarding sexuality and body satisfaction. PMID- 9367453 TI - FK 506 'rescue' immunosuppression for obliterative bronchiolitis after lung transplantation. AB - PRELIMINARY EXPERIENCE: In a consecutive case series (level V evidence) involving 10 recipients of unilateral lung transplantation (LT) with bronchiolitis obliterans, in conjunction with Fujisawa protocol 93-0-003, the physiologic responses to FK 506 (tacrolimus) "rescue" immunosuppression were assessed. Recipients were 22+/-18 months post-LT and demonstrated progressive allograft dysfunction that was refractory to pulsed-dose methylprednisolone therapy. All recipients received induction immunosuppression with Minnesota antilymphocyte globulin (10 to 15 mg/kg/d) for 5 to 10 days, cyclosporine (CsA) (whole-blood Abbott TDX fluorescence polarization immunoassay (Abbott Inc, Abbott Park, IL)=600 to 800 ng/mL), azathioprine (2 mg/kg/d), and prednisone (tapered to 0.2 mg/kg/d). The "rescue" regimen consisted of oral FK 506 adjusted to maintain a whole-blood Abbott IMX microparticle enzyme immunoassay (Abbott Inc, Abbott Park, IL) of 10 to 15 ng/mL with an initial increase in prednisone (1.0 mg/kg/d) during conversion that was subsequently tapered to 0.2 mg/kg/d. Spirometry was performed monthly in accordance with accepted American Thoracic Society criteria. Recipients were classified in accordance with the International Society for Heart and Lung Transplantation (ISHLT) "Working Formulation for Standardization of Nomenclature and for Clinical Staging of Chronic Dysfunction in Lung Allografts" as stages Ib (n=2), IIb (n=4), and IIIb (n=4) upon entry to the protocol. The deltaFEV1/month relationships during CsA- and FK 506-based regimens were analyzed by linear regression and compared by signed rank test (p<0.05). RESULTS: The deltaFEV1/month slopes were -0.0687+/-0.0221 and +0.0300+/-0.033 L/mo (mean+/ SEM) for CsA and FK 506, respectively (p=0.037). Although no significant spirometric improvement was noted in most recipients, no further decline in FEV1 occurred after conversion to FK 506. Recipients with less severe chronic dysfunction (ie, obliterative bronchiolitis [OB] stages Ib and IIb) stabilized their spirometric indexes at higher levels. Two recipients with OB stage IIIb died of hypercapnic respiratory failure at 6 and 8 months after conversion. CONCLUSIONS: The deltaFEV1/mo slopes stabilized after FK 506 conversion. Earlier conversion may be beneficial in stabilizing FEV1 at a higher plateau. Significant economic impact may be anticipated with FK 506 compared to alternative cytolytic strategies for OB. However, multicenter prospective controlled investigations are necessary to further address the potential role of FK 506 after LT (level I evidence). Furthermore, the ISHLT "Staging of OB Syndrome" may have significant clinical implications vis-a-vis prognosis and potential therapies. PMID- 9367454 TI - Activation of eosinophils in the airways of lung transplantation patients. AB - Eosinophils are important inflammatory cells involved in liver and renal allograft rejection. The role of these cells is less well defined in lung allograft rejection. Eosinophils may be activated in lung rejection and release cytotoxic eosinophil cationic protein (ECP). Other states of disease in lung transplant recipients, such as cytomegalovirus (CMV) and bacterial infection, may also be associated with activated eosinophils. We postulated that ECP may be detectable and elevated in the airway lavage samples obtained from lung transplant patients and may contribute to disease pathogenesis. METHODS: Fifty BAL samples were collected from 38 lung transplant patients. Their most recent pulmonary function test results within 1 week of collection were noted. The samples were analyzed for the concentration of ECP, WBC count and differential cell count, and total protein level. The results were analyzed to identify the presence of disease or abnormal lung function associated with a positive ECP test. Student's t test was used and a p value of <0.05 was considered significant. RESULTS: We found that ECP levels were elevated in 36% (n=14) of the patients. Those patients with a positive test result were more likely to have acute rejection, CMV disease, or the presence of a cultured pathogen in BAL compared to patients with a negative test result (p<0.01). CONCLUSIONS: The presence of BAL ECP is associated with disease in lung transplant patients. Since ECP is directly cytotoxic, it may contribute to disease pathogenesis. PMID- 9367455 TI - Upregulation of collagen messenger RNA expression occurs immediately after lung damage. AB - BACKGROUND: Mortality of ARDS still exceeds 50%. Though pulmonary fibrosis is a marker of severe prognosis in the evolution of ARDS, its onset is not yet established. Cardiopulmonary bypass (CPB), usually utilized in patients with a previously normal lung, can cause ARDS and often causes alveolar damage, the earliest lesion observed in ARDS, thus providing a unique opportunity to study the molecular mechanisms of fibrogenesis. OBJECTIVE: To measure immediately after CPB, at the onset of alveolar damage, the expression of messenger RNAs (mRNAs) for collagen type I. METHODS: Pre-CPB and post-CPB lung biopsy specimens were obtained from patients submitted to myocardial revascularization for coronary artery disease. Alveolar damage was characterized by comparison between before and after specimens and quantified by point counting of polymorphonuclear cells (PMN). Type I collagen mRNAs were quantified by scanning densitometry of Northern blot autoradiographs, corrected for RNA loading by 18S ribosomal RNA hybridization. RESULTS: Alveolar damage was characterized by lung interstitial edema and by polymorphonuclear cell infiltration after CPB (PMN pre-CPB 0.010+/ 0.004xPMN post-CPB 0.052+/-0.022; n=7; p=0.0017, t test). Type I collagen mRNA increased 91.1+/-68.2% (Ln pre-CPBxLn post-CPB; n=15; p<0.00001, t test) immediately after CPB (mean CPB time, 108.8+/-37.2 min). CONCLUSION: Fibrogenesis, as measured at the molecular level, is a very early event following diffuse alveolar damage, attributable mainly to resident fibroblast activation. PMID- 9367456 TI - Relationship between preoperative endotoxin immune status, gut perfusion, and outcome from cardiac valve replacement surgery. AB - STUDY OBJECTIVE: Endotoxin is a powerful trigger of systemic inflammation. Since cardiac surgery exposes patients to endotoxemia, this study was set up to define the relationship between preoperative endogenous endotoxin immune status, gut perfusion, and outcome following cardiac valve replacement surgery. DESIGN: Observational study. SETTING: University hospital. PATIENTS: Fifty-nine consecutive patients undergoing cardiac valve replacement. MEASUREMENTS AND MAIN RESULTS: Blood was assayed for IgG and IgM endotoxin core antibody (EndoCAb) levels preoperatively, immediately postoperatively, and at 4 h and 24 h postoperatively. Intraoperative gut mucosal perfusion was assessed using gastric tonometry. Complications were assessed for groups above and below the median EndoCAb value of a healthy population (100 median units micro/mL). Of the 59 patients, 12 developed at least one of a set of predefined complications. Of these 12, all had preoperative levels of IgM EndoCAb below 100 MU/mL (p<0.025). Eleven had IgG EndoCAb levels below 100 MU/mL (0.05
30) (p values <0.05 for comparisons of OSA groups with habitual snorers). Compared to subjects with mild OSA or habitual snorers, BP night/day ratios were greater in patients with severe OSA (p values <0.05). Accordingly, hypertension and nondipping increased as ODI increased. CONCLUSION: OSA is associated with hypertension independent of the confounding factors of age and obesity. Nondipping is related to apnea severity. These alterations might contribute to the increased mortality in patients with severe OSA. PMID- 9367466 TI - Long-term efficiency of home nasal mask ventilation in patients with diffuse bronchiectasis and severe chronic respiratory failure: a case-control study. AB - The aim of this study was to evaluate long-term efficacy and tolerance of nasal mask ventilation (NMV) in a comparative case-control study. Fourteen patients with diffuse bronchiectasis and severe chronic respiratory failure (CRF), treated by long-term oxygen-therapy (LTO) and NMV, were case matched with 14 patients with diffuse bronchiectasis and severe CRF treated with only LTO. Patients and control subjects were compared based on the following parameters: blood gases, FEV1, vital capacity, hospitalizations, and survival. Symptoms, Karnofsky function score, and clinical evolution were also monitored in patients. Three subgroups may be identified according to outcome: two early deaths (subgroup 1), six patients with initial improvement and subsequent deterioration (subgroup 2), and six patients whose conditions remained improved for >2 years (subgroup 3). PaO2 decrease slope was slighter in this last subgroup than subgroup 2. The days of hospitalization were significantly reduced after institution of NMV in the patient group. Comparison between patients and control subjects did not show any difference on PaO2 evolution and on the overall median survival (46 and 40 months in NMV and control group, respectively). Long-term tolerance and compliance remained satisfactory for 11 patients. These results suggest that NMV is feasible as a long-term home treatment in patients with diffuse bronchiectasis. Although our results may have failed to prove a long-term efficiency on the course of blood gases and survival, a beneficial effect is observed with reduction of hospitalizations and improvement of functional status. This study warrants further investigation, in a prospective series, with a larger number of patients. PMID- 9367467 TI - Effectiveness of controlled and spontaneous modes in nasal two-level positive pressure ventilation in awake and asleep normal subjects. AB - STUDY OBJECTIVES: The purpose of the present study was to compare in awake and asleep healthy subjects, under nasal intermittent positive pressure ventilation (nIPPV) with a two-level intermittent positive pressure device (two-level nIPPV), the efficacy of the controlled and spontaneous modes, and of different ventilator settings in increasing effective minute ventilation (VE). PARTICIPANTS: Eight healthy subjects were studied. SETTING: In the controlled mode, inspiratory positive airway pressure (IPAP) was kept at 15 cm H2O, expiratory positive airway pressure (EPAP) at 4 cm H2O, and the inspiratory/expiratory (I/E) time ratio at 1. The respirator frequencies were 17 and 25/min. In the spontaneous mode experiment, IPAP was started at 10 cm H2O and progressively increased to 15 and 20 cm H2O; EPAP was kept at 4 cm H2O. MEASUREMENTS AND RESULTS: We measured breath by breath the effective tidal volume (VT with respiratory inductive plethysmography), actual respiratory frequency (f), and effective VE. Using the controlled mode, effective VE was significantly higher on nIPPV than during spontaneous unassisted breathing, except in stage 2 nonrapid eye movement sleep at 17/min of frequency; increases in f from 17 to 25/min led to a significant decrease in VT reaching the lungs, during wakefulness and sleep; effective VE was higher at 25 than at 17/min of frequency only during sleep; periodic breathing was scarce and apneas were never observed. Using the spontaneous mode, with respect to awake spontaneous unassisted breathing, two-level nIPPV at 10 and 15 cm H2O of IPAP did not result in any significant increase in effective VE either in wakefulness or in sleep; only IPAP levels of 20 cm H2O resulted in a significant increase in effective VE; during sleep, effective VE was significantly lower than during wakefulness; respiratory rhythm instability (ie, periodic breathing and central apneas) were exceedingly common, and in some subjects extremely frequent, leading to surprisingly large falls in arterial oxygen saturation. CONCLUSIONS: It appears that two-level nIPPV should be used in the controlled mode rather than in the spontaneous mode, since it seems easier to increase effective VE with a lower IPAP at a high frequency than at a high pressure using the spontaneous mode. We suggest that the initial respirator settings in the controlled mode should be an f around 20/min, an I/E ratio of 1, 15 cm H2O of IPAP, and EPAP as low as possible. PMID- 9367468 TI - Home nebulized therapy for patients with COPD: patient compliance with treatment and its relation to quality of life. AB - STUDY OBJECTIVES: To assess compliance with home nebulized therapy in patients with COPD. DESIGN: Patients' home nebulizers were replaced with nebulizers that recorded the date and time of each treatment over a period of 4 weeks. Poor compliance was defined as taking <70% of the prescribed dose (or <60% for those prescribed treatments five or more times daily). SETTING: Patients were seen at the hospital COPD outpatient clinic. The compliance data obtained were recorded while they were at home. PATIENTS: Ninety-three patients aged 44 to 76 years (mean, 64.9 years) were recruited from the hospital nebulizer database. MEASUREMENTS: Patients completed a self-reported quality of life scale, the St. George's Respiratory Questionnaire (SGRQ), both before (SGRQ1) and after (SGRQ2) the 4-week study period to look at whether quality of life was either predictive of or subsequent to level of compliance. RESULTS: Data were obtained from 82 patients. Mean compliance was 57% (range, 0 to 124%). Thirty-six (44%) patients were compliant and 46 (56%) were poorly compliant. There was no difference between the two groups in age or sex distribution. Compliance was negatively correlated with the total score on the SGRQ2 (p=0.03). CONCLUSION: The study shows that levels of compliance with nebulized therapy are low in a large proportion of patients with COPD and that patients with low levels of compliance report greater impairment in their quality of life. PMID- 9367469 TI - Airway deposition and clearance and systemic pharmacokinetics of amiloride following aerosolization with an ultrasonic nebulizer to normal airways. AB - STUDY OBJECTIVES: Airway epithelial ion transport is an important component of the airway defense mechanism, and new therapies that target ion transport are being developed. Amiloride is an example of such a new drug, exerting a dose dependent action to inhibit Na+ transport. Amiloride may be useful in cystic fibrosis, blocking the characteristic airway epithelial Na+ hyperabsorption that occurs in the disease. To evaluate airway and systemic delivery of amiloride via an ultrasonic nebulizer (Omron NE-UO7), we measured the airway surface concentrations of amiloride in normal volunteers via a novel approach, together with the systemic pharmacokinetics of amiloride. DESIGN: Direct measurement of airway surface liquid, plasma, and urine amiloride concentrations following ultrasonic nebulization. PARTICIPANTS/INTERVENTIONS: Seven normal subjects were studied in the General Clinical Research Center of the University of North Carolina. Following inhalation with amiloride (1 mg/mL, 4.5 mL) for approximately 12 min, a bronchoscopy was performed. Amiloride deposition and clearance from airway surfaces over 1 h were evaluated by transbronchoscopic sampling using preweighed filter papers. Pulmonary and systemic absorption was assessed by measuring drug concentrations in blood and urine. RESULTS: The mean volume aerosolized was 3.5+/-0.3 mL during 12 min of aerosolization time; the mean initial concentration of amiloride on airway surfaces after nebulization was 1.6 x 10(-4) mol/L, with an elimination half life of approximately 23 min. Peak plasma concentrations of amiloride (30 min, 3.36+/-0.70 ng/mL) suggest early absorption across lung surfaces, rather than via the GI route. Mean urinary excretion of amiloride over 72 h was 0.63+/-0.07 mg, with 87% excreted in the first 24 h. CONCLUSIONS: The ultrasonic nebulizer rapidly delivers amiloride to normal conducting airways as assessed by the transbronchoscopic sampling technique. Early blood concentrations of amiloride probably reflect initial absorption across lung surfaces and are a useful index of the efficiency of the machine. PMID- 9367470 TI - Is pH paper an acceptable, low-cost alternative to the blood gas analyzer for determining pleural fluid pH? AB - BACKGROUND: Our laboratory uses pH paper rather than a blood gas analyzer to measure pleural fluid pH to decrease cost and avoid analyzer malfunction due to viscous fluids. METHODS: To compare these two methods of determining pleural fluid pH, 42 patients undergoing diagnostic or therapeutic thoracentesis had two 1-mL aliquots of pleural fluid anaerobically collected in a heparinized syringe and placed on ice. pH measurements were made using litmus paper (pHydron Vivid 6 8 brand litmus paper; MicroEssential Labs; Brooklyn, NY) and the model 995-Hb blood gas analyzer (AVL Instruments; Roswell, GA) within 1 h of collection. Agreement analysis was performed in three ways: on the entire group; in subcategories of complicated or uncomplicated parapneumonic effusions (<7.1, 7.1 to 7.3, >7.3); and in subcategories of poor prognosis or better prognosis malignant effusions(<7.3, >7.3). RESULTS: pH measured with pH paper was significantly more variable (SD=0.55, coefficient of variation [CV]=7.5%) than was pH measured with the blood gas analyzer (SD=0.11, CV=1.5%). There was no significant correlation between values obtained with the two techniques (r=-0.26, SD of the differences=0.59). Using the pH subcategories, there was 72% discordance in classification between litmus paper and arterial blood gas (ABG) determinations for patients with parapneumonic effusions. In patients with malignant effusions, there was 30% discordance. The pH values obtained by the ABG analyzer predicted tube thoracostomy 72% of the time, whereas the pH values obtained using pH paper were consistent only 36% of the time. CONCLUSION: Determination of pleural fluid pH using pH paper is unreliable and should not be considered an acceptable alternative to the blood gas analyzer. There is no need to determine pH on purulent samples. Hospital laboratories will be more likely to allow the use of the ABG analyzer on fluids other than blood if clinicians keep this in mind. PMID- 9367471 TI - Are pleural fluid parameters related to the development of residual pleural thickening in tuberculosis? AB - STUDY OBJECTIVE: Identification of predictive factors for the development of residual pleural thickening (RPT). DESIGN: Retrospective study. LOCATION: A 1,500 bed tertiary hospital. PATIENTS: Patients with pleural tuberculosis diagnosed between December 1991 and February 1995 in our Respiratory Disease Service. INTERVENTIONS: The clinical and radiologic characteristics, and measurements of microbiological and biochemical parameters and markers in pleural fluid were studied. RPT was defined in a posteroanterior chest radiograph as a pleural space of >2 mm measured in the lower lateral chest at the level of an imaginary line intersecting the diaphragmatic dome. MEASUREMENTS AND RESULTS: In 56 patients studied, 11 (19.6%) had RPT 10 mm and 24 (42.8%) had RPT >2 mm. The pleural fluid of patients with RPT 10 mm had a significantly lower glucose concentration and pH and higher lysozyme and tumor necrosis factor-alpha levels than the other patients. The pleural fluid of patients with RPT >2 mm showed no significant differences. CONCLUSIONS: The development of RPT 10 mm was related to higher concentrations of lysozyme and tumor necrosis factor-alpha and lower glucose concentration and pH in pleural fluid compared with development of lower measurements of RPT. PMID- 9367472 TI - Home inotropic therapy in advanced heart failure: cost analysis and clinical outcomes. AB - STUDY OBJECTIVES: This study was conducted to assess cost savings and clinical outcomes associated with the use of home i.v. inotropic therapy in patients with advanced (New York Heart Association [NYHA] class IV) heart failure. DESIGN: Retrospective analysis. SETTING: Tertiary care referral center. PATIENTS AND INTERVENTIONS: Twenty-four patients (13 men, 11 women; age, 61+/-12 years) with left ventricular ejection fraction <30% and heart failure refractory to oral agents required home i.v. inotropic therapy for at least 4 consecutive weeks between May 1994 and April 1996. Inotropic agents used included dobutamine (n=20; dose, 5.0+/-2.2 microg/kg/min) or milrinone (n=7; dose, 0.53+/-0.05 microg/kg/min). MEASUREMENTS AND RESULTS: Cost of care and clinical outcomes (hospital admissions, length of hospital stay, NYHA functional class) were compared during the period of inotropic therapy (study period) and the immediate preceding period of equal duration (control period). In comparison to the control period, the study period (3.9+/-2.7 months) was associated with a 16% reduction in cost, amounting to a calculated savings of $5,700 per patient or $1,465 per patient per month. Concomitantly, a decrease in the number of hospital admissions from 2.7+/-2.6 to 1.3+/-1.3 (p=0.056) and length of hospital stay from 20.9+/ 12.7 to 5.5+/-5.4 days (p=0.0004) was observed with improvement in NYHA functional class from 4.0+/-0.0 to 2.7+/-0.9 (p<0.0001). Eight patients (38%) died after 2.8+/-1.7 months of home i.v. inotropic therapy. CONCLUSIONS: Home i.v. inotropic therapy reduces hospital admissions, length of stay, and cost of care and improves functional class in patients with advanced (NYHA class IV) heart failure. PMID- 9367473 TI - Multimodality treatment of esophageal disruptions. AB - The treatment of esophageal disruptions has changed since 1981. The value of a more selective assessment in six spontaneous ruptures and 30 mostly intrathoracic (83.4%) esophageal perforations is evaluated in this study. Based on the previous state of the esophagus, the time factor, and type and site of the disruption, reinforced primary repair (by diaphragmatic, muscular, pleural flap, or fundoplication), transhiatal closure, resection, intubation, suture combined with myotomy and fundoplication, esophageal diversion, and transhiatal mediastinal drainage were employed. The overall 30-day hospital mortality was 19.4%. Although these operations were mostly used in late (24 h to 7 months) perforations and ruptures, none of the patients with reinforced repair by autogenous diaphragmatic, muscular, or pleural flaps or fundoplication had fatal outcome for breakdown of the closure. Only patients with renal, cardiac, or multiorgan failure as a consequence of sepsis due to time elapsed before hospital admission died. The key to improve the prognosis of this life-threatening emergency is the more appropriate selection of the primary employed procedure. PMID- 9367474 TI - Diagnosis and treatment of shock due to massive pulmonary embolism: approach with transesophageal echocardiography and intrapulmonary thrombolysis. AB - STUDY OBJECTIVES: To evaluate the diagnostic value of transesophageal echocardiography (TEE) as an initial diagnostic tool in shocked patients. The second objective was to study therapeutic impact of intrapulmonary thrombolysis in patients with diagnosed massive pulmonary embolism. DESIGN: Prospective observational study. SETTING: Medical ICU in 800-bed general hospital. PATIENTS: Twenty-four consecutive patients with unexplained shock and distended jugular veins. MEASUREMENTS AND MAIN RESULTS: In 18 patients, right ventricular dilatation with global or segmental hypokinesis was documented. In addition, central pulmonary thromboemboli (12 patients), reduced contrast flow in right pulmonary artery (one patient), and right ventricular free wall akinesis (one patient) were found. No additional echocardiographic findings were apparent in four patients. According to pulmonary scintigraphy or autopsy, sensitivity of TEE for diagnosis of massive pulmonary embolism (MPE) in patients with right ventricular dilatation was 92% and specificity was 100%. In patients without right ventricular dilatation, left ventricular dysfunction (four patients) or cardiac tamponade (two patients) was confirmed. Intrapulmonary thrombolysis was evaluated in 11 of 13 patients with MPE. Two patients died prior to attempted thrombolysis. Three patients received streptokinase and eight received urokinase. Twenty-four hours after beginning of treatment, total pulmonary resistance index significantly decreased for 59% and mean pulmonary artery pressure for 31%. Cardiac index increased for 74%. Nine of 11 patients receiving thrombolysis survived to hospital discharge. CONCLUSION: Bedside TEE is a valuable tool for diagnosis of MPE. It enables immediate intrapulmonary thrombolysis, which seems to be an effective therapeutic alternative in our group of patients with obstructive shock. PMID- 9367475 TI - Characteristics and outcomes of patients who self-extubate from ventilatory support: a case-control study. AB - OBJECTIVE: To identify factors associated with the occurrence of deliberate self extubation and to describe associated patient outcomes. DESIGN: Case-control study. SETTING: ICUs of a national referral, tertiary medical center. PARTICIPANTS: Fifty adult, intubated patients who had self-extubated from mechanical ventilatory support. Two control subjects who had not self-extubated were matched to each case based on age, gender, primary discharge diagnosis, and time hospitalized (within same quarter). MEASUREMENTS: Standardized coding of medical record information, including demographic characteristics, clinical information, intubation and mechanical ventilation characteristics, medications, and selected laboratory indexes. RESULTS: As compared to the control subjects, patients who self-extubated were more likely to be medical than surgical patients (p<0.001) and have a current history of smoking (p<0.05). Prior to the self extubation, patients had a greater likelihood of hospital-acquired infections (p<0.001) or other hospital-acquired adverse events (p<0.001), abnormal (<10, >50 mg/dL) BUN (p<0.05), and abnormal (<20, >50 mm Hg) PaCO2 (p<0.05); they also were more likely to be restless or agitated (p<0.001), and more likely to be physically restrained (p<0.001). A logistic regression model demonstrated that presence of restlessness or agitation and presence of a hospital-acquired adverse event were independently associated with self-extubation from mechanical ventilatory support. In examining outcomes, as compared to the control subjects, those who self-extubated had longer lengths of stay in ICU and hospital, were more likely to need reintubation, and were more likely to suffer complications from intubation. However, none of the cases died within 48 h of self-extubation. CONCLUSION: The results underscore the need for clinical guidelines for weaning and for monitoring patients at risk of self-extubation. PMID- 9367476 TI - A randomized, controlled study of the 1-hour and 24-hour effects of inhaled nitric oxide therapy in children with acute hypoxemic respiratory failure. AB - STUDY OBJECTIVE: To determine whether 24 h of inhaled nitric oxide improves oxygenation greater than conventional therapy alone in children with acute hypoxemic respiratory failure. DESIGN: Prospective, randomized, controlled study. SETTING: Twenty-six-bed pediatric ICU in a tertiary children's hospital. PATIENTS: Twenty-four patients with acute bilateral lung disease requiring a positive-end expiratory pressure >6 cm H2O and a fraction of inspired oxygen >0.5 for >12 h. INTERVENTIONS: Twelve patients were treated with 10 ppm inhaled nitric oxide from the onset of randomization and 12 control patients were initially maintained on a regimen of conventional therapy alone. After a period of 24 h, control patients were also treated with 10 ppm inhaled nitric oxide. Hemodynamic and blood gas measurements were performed at baseline, at 1 h after randomization, and at 24-h intervals for 2 days. MEASUREMENTS AND RESULTS: Inhaled nitric oxide decreased the ratio of pulmonary to systemic vascular resistance and improved oxygenation indexes during the initial hour following randomization. However, 24 h after randomization, the oxygenation indexes of 11 surviving treated patients were not improved in comparison to baseline or the oxygenation indexes of 10 surviving control patients. Oxygenation indexes acutely improved in control patients when inhaled nitric oxide was started after 24 h of conventional therapy. Oxygenation indexes remained improved in the initial control patients after 24 h of inhaled nitric oxide. CONCLUSIONS: Pulmonary vascular resistance and systemic oxygenation are acutely improved by 10 ppm inhaled nitric oxide in some children with severe lung disease. However, a sustained improvement in oxygenation may not occur during prolonged therapy. Thus, inhaled nitric oxide may have a limited therapeutic role in children with acute hypoxemic respiratory failure. PMID- 9367477 TI - Combination therapy with suicide and cytokine genes for hepatic metastases of lung cancer. AB - Metastases of lung cancer are a major cause of treatment failure. To evaluate the therapeutic efficacy of gene therapy in metastatic lung cancer, we used adenoviral (ADV) mediated transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene and the cytokine gene interleukin-2 (IL-2) to treat a murine model of metastatic lung cancer in the liver. Hepatic metastases were established by intrahepatic implantation of LL2 cells in syngeneic recipient mice. One week after tumor implantation, various replication defective ADV vectors were injected intratumorally. Treatment with a vector expressing the HSV-tk followed by ganciclovir administration with ADV.tk resulted in significant regression of tumor (p<0.01) as well as prolongation of survival (p<0.001). While a vector expressing mouse IL-2 ADV.IL-2 alone was ineffective, combination therapy with HSV-tk resulted in further tumor regression and improvement of animal survival (p<0.05). These results demonstrate that suicide and cytokine genes can be utilized in combination to treat metastatic lung cancer in vivo. PMID- 9367478 TI - The role of neutrophils in the pathogenesis of idiopathic pulmonary fibrosis. AB - STUDY OBJECTIVES: The prognostic value of the neutrophil count in BAL fluid (BALF) has been controversial. The role of neutrophils in this inflammatory lung disease, therefore, was evaluated in this study by additional measures. MATERIALS AND METHODS: We performed BAL in 22 patients with idiopathic pulmonary fibrosis (IPF) diagnosed by open lung biopsy specimen. Percent polymorphonuclear leukocyte (PMN) in BALF and absolute neutrophil counts were compared with those of normal nonsmokers. Elastase complexed to alpha-1-proteinase inhibitor (alpha1-PI) in plasma and BALF was measured as a marker of elastase burden, and neutrophil distribution in 22 lung tissues was observed by immunohistochemistry using antineutrophil elastase antibody. RESULTS: Percent PMN and absolute neutrophil counts in BALF did not increase in patients with IPF as compared with normal nonsmokers (n=15); the plasma elastase-alpha1-PI complex value (mean+/-SE) of patients with IPF (668.5+/-112.4 ng/mL) was significantly high as compared with that of normal nonsmokers (130.3+/-21.3, p<0.001). In addition, the BALF elastase alpha1-PI complex value (mean+/-SE) of patients with IPF was also significantly high (333.1+/-87.0 ng/mg albumin) as compared with that of normal nonsmokers (83.1+/-29.3 ng/mg albumin, p<0.05). Immunohistochemistry demonstrated considerable numbers of neutrophils infiltrating the lung parenchyma in biopsy specimens obtained by open lung biopsy. CONCLUSIONS: These results suggested that although the neutrophil count in BALF could not represent the distribution of neutrophil in the lung, high levels of neutrophil elastase were demonstrated in lung parenchyma and also in both BALF and sera. Therefore, neutrophils might indeed play an important role in the pathogenesis of IPF. PMID- 9367479 TI - Primary mediastinal tumors: part II. Tumors of the middle and posterior mediastinum. AB - Lymphoma, mediastinal cysts, and neurogenic neoplasms are the most common primary middle and posterior mediastinal tumors. Lymphoma may involve the anterior, middle and/or posterior mediastinum, frequently as lymphadenopathy or as a discrete mass. Foregut cysts are common congenital mediastinal cysts and frequently arise in the middle mediastinum. Pericardial cysts are rare. Schwannoma and neurofibroma are benign peripheral nerve neoplasms, represent the most common mediastinal neurogenic tumors, and rarely degenerate into malignant tumors of nerve sheath origin. Sympathetic ganglia tumors include benign ganglioneuroma and malignant ganglioneuroblastoma and neuroblastoma. Lateral thoracic meningocele is a rare cause of a posterior mediastinal mass. PMID- 9367480 TI - Apoptosis and the heart. PMID- 9367481 TI - Pulmonary rehabilitation: joint ACCP/AACVPR evidence-based guidelines. ACCP/AACVPR Pulmonary Rehabilitation Guidelines Panel. American College of Chest Physicians. American Association of Cardiovascular and Pulmonary Rehabilitation. PMID- 9367482 TI - Genetics of asthma: a review. PMID- 9367483 TI - What is 'minimally invasive' coronary bypass surgery? Experience with a variety of surgical revascularization procedures for single-vessel disease. AB - BACKGROUND: Although the use of small incisions is theoretically appealing, it has been argued that the true advantage of minimally invasive approaches to myocardial revascularization lies in the avoidance of cardiopulmonary bypass. METHODS: Of 25 patients referred for surgical revascularization of single-vessel coronary disease, 20 elected to undergo a minimally invasive coronary artery bypass grafting (MICABG) procedure, while 5 opted to have conventional surgery with cardiopulmonary bypass (CPB). Patients having MICABG underwent single-vessel revascularization without CPB, via limited anterior thoracotomy, hemisternotomy, or median sternotomy. Intraoperatively, hemodynamics, anastomotic time, and total operative time were recorded. Postoperatively, length of hospital stay, incidence of myocardial infarction, indexes of end-organ function, and morbidity rates were recorded. In addition, patient questionnaires were used to assess subjective end points such as postoperative pain, wound drainage, and quality of life. RESULTS: Fifteen of 20 patients undergoing MICABG underwent revascularization without CPB, while 4 were converted to standard coronary artery bypass grafting with CPB due to technical reasons and 1 for intraoperative ventricular fibrillation. Patients undergoing MICABG had no perioperative myocardial infarctions, while those having CPB had two infarctions (20%). Furthermore, there were no differences in length of stay or postoperative morbidity among the various approaches, while the MICABG procedures, especially via median sternotomy, were associated with shorter operative times. CONCLUSIONS: The advantage of MICABG lies mainly in the avoidance of CPB. Thus, we advocate that surgeons initially utilize the median sternotomy and limited skin incision for MICABG to assure adequate exposure, technical precision, and patient safety. After a reasonable level of technical proficiency and experience are attained, the limited anterior thoracotomy approach can be used. PMID- 9367484 TI - Simultaneous bilateral pneumothorax in an HIV-infected patient. PMID- 9367485 TI - Sudden respiratory insufficiency in a previously healthy 47-year-old man. PMID- 9367486 TI - Successful double-lung transplantation for bronchioalveolar carcinoma. PMID- 9367487 TI - Solitary fibrous tumor of the pleura: a report of five cases diagnosed by transthoracic cutting needle biopsy. AB - Five patients had a solitary fibrous tumor of the pleura; a well-known but rare entity. In all cases, biopsy by a transthoracic cutting needle (Tru-Cut; Travenol; Deerfield, IL) yielded specimens adequate for histologic analysis and gave the clue to the diagnosis. In four patients, surgical resection confirmed the diagnosis. The opportunity for and interest in diagnosing these tumors by transthoracic cutting needle biopsy before surgery are discussed. An accurate diagnosis of solitary fibrous tumors of the pleura can be made by a minimally invasive procedure; this allows for a more informed allocation of surgical resources. PMID- 9367488 TI - Mycoplasma hominis pneumonia complicating bilateral lung transplantation: case report and review of the literature. AB - Mycoplasma hominis is a commensal of humans. The organism has been predominantly associated with infections of the genitourinary tract. Extragenital infections have been described in neonates, in women during the postpartum period, and in immunocompromised patients. Pneumonia caused by M. hominis is very rare. This report describes the development of M. hominis pneumonia in a lung transplantation recipient and underscores the difficulty in establishing the correct diagnosis and the need for early and aggressive treatment with appropriate antimicrobial agents to insure a good outcome. PMID- 9367489 TI - Nonsurgical therapy for pulmonary hydatid cyst disease. AB - Therapeutic and diagnostic aspiration of Echinococcus granulosus liver cysts, but not pulmonary cysts, are increasingly being performed. Documented herein is the utility of percutaneous drainage and of albendazole treatment in a patient with a large recurrent, isolated, pulmonary echinococcal cyst for whom traditional therapy would have resulted in severe morbidity. Therapeutic options and possible complications are discussed. PMID- 9367490 TI - Silica-induced pleural disease: an unusual case mimicking malignant mesothelioma. AB - A 57-year-old man with a history of exposure to silica for 32 years presented with pleural thickening of the lower lobe of the left lung and a chronic right sided pleural effusion without any radiographic evidence of parenchymal nodules in either lung. Light microscopic examination of a left visceral pleural biopsy specimen revealed markedly thickened pleura with fibrosis and macrophages containing birefringent silica and silicates. Occasional rounded intrapleural silicotic nodules were present. The underlying lung tissue did not show fibrosis or silicotic nodules. An energy-dispersive x-ray analysis confirmed the presence of silica. In the absence of lung involvement, this case represents a very unusual pathologic reaction caused by silica and silicates and adds to the clinical differential diagnosis of chronic pleuritis and malignant mesothelioma. PMID- 9367491 TI - Superior vena cava obstruction secondary to mediastinal lymphadenopathy in a patient with cystic fibrosis. AB - Superior vena cava (SVC) obstruction most often is a complication of malignant tumors such as lung cancer or lymphoma. The common use of long-term indwelling central venous catheters also has added to the prevalence of SVC obstruction. This report describes the first case of SVC obstruction in a patient with cystic fibrosis due to extrinsic compression from benign reactive mediastinal lymphadenopathy. Although in these circumstances intravascular thrombosis should be ruled out, extrinsic compression from mediastinal lymphadenopathy should be considered. PMID- 9367492 TI - Pneumopericardium associated with face-mask continuous positive airway pressure. AB - This is an uncommon case of a patient who developed pneumopericardium while being treated with face-mask continuous positive airway pressure (CPAP) for hypoxic respiratory failure following a coronary artery bypass graft surgery. A pneumopericardium detected by chest radiograph resolved completely after discontinuation of face-mask CPAP. Possible mechanisms that may have been involved in this unusual complication are reviewed. PMID- 9367493 TI - Management of asthma: applied knowledge is power. PMID- 9367494 TI - Anesthetic cream for arterial cannulation. PMID- 9367495 TI - Possible role of buspirone hydrochloride in smoking cessation. PMID- 9367496 TI - Theoretical and experimental considerations of the pseudo-first-order approximation in conventional kinetic analysis of IAsys biosensor data. AB - The validity of the conventional interpretation of IAsys biosensor profiles in terms of pseudo-first-order kinetic behavior is subjected to closer scrutiny by its application to simulated data for low- and high-affinity interactions between ligate and immobilized ligand. As might reasonably have been expected, analysis of the simulated data for the low-affinity system (association equilibrium constant of 10(5) M-1) in such terms returned the input association and dissociation rate constants (10(3) M-1 s-1 and 10(-2) s-1, respectively)-a consequence of essential compliance with the assumed constancy of ligate concentration in the liquid phase. For the high-affinity interaction (ka = 10(5) M-1 s-1, kd = 10(-2) s-1, KAX = 10(7) M-1) the ligate concentration was depleted by up to 35%, and hence its assumed constancy was clearly an untenable approximation. Whereas no symptomatic evidence of such violation (apart from the return of incorrect estimates of ka and kd) was evident from pseudo-first-order kinetic analysis of the adsorption profiles, the corresponding analysis of desorption profiles was more informative in that the data deviated demonstrably from pseudo-first-order kinetic behavior. A second-order kinetic analysis was therefore developed and shown to be applicable to adsorption and desorption profiles, irrespective of the validity or otherwise of the pseudo-first-order kinetic approximation. Experimental results obtained for the interaction of histidine-rich glycoprotein with immobilized IgG were then used to illustrate various features of the pseudo-first-order and second-order kinetic analyses, and to determine from the second-order analysis an association equilibrium constant of 2 x 10(8) M-1, which is 20-fold greater than the value obtained by interpretation of the profiles in terms of pseudo-first-order kinetic behavior. PMID- 9367497 TI - Seven-color time-resolved fluorescence hybridization analysis of human papilloma virus types. AB - Identification of human papilloma virus (HPV) types is important in order to determine the risk of cervical carcinoma in women. This requires a technique to probe individual samples for multiple virus specificities. Here we describe simultaneous multicolor analysis of amplification products for any of seven amplified HPV types 16, 18, 31, 33, 35, 39, and 45, associated with cancer of the cervix. A seminested polymerase chain reaction was performed in a single tube using a biotinylated inner primer. Sets of amplification products, immobilized on a 96-pronged manifold solid support, were rendered single stranded and probed with a mix of seven type-specific, differentially labeled oligonucleotides. These probes contained 10 or 20 lanthanide chelates at the 5' ends with seven distinct combinations of europium, terbium, and samarium ions. The seven viral strains were correctly identified by time-resolved fluorescence measurement of the specifically hybridized probes. Using this assay format, simultaneous detection of any of seven or even more target variants is possible. PMID- 9367498 TI - A stable nonfluorescent derivative of resorufin for the fluorometric determination of trace hydrogen peroxide: applications in detecting the activity of phagocyte NADPH oxidase and other oxidases. AB - The enzymatic determination of hydrogen peroxide can be accomplished with high sensitivity and specificity using N-acetyl-3, 7-dihydroxyphenoxazine (Amplex Red), a highly sensitive and chemically stable fluorogenic probe for the enzymatic determination of H2O2. Enzyme-catalyzed oxidation of Amplex Red, which is a colorless and nonfluorescent derivative of dihydroresorufin, produces highly fluorescent resorufin, which has an excitation maximum at 563 nm and emission maximum at 587 nm. The reaction stoichiometry of Amplex Red and H2O2 was determined to be 1:1. This probe allows detection of 5 pmol H2O2 in a 96-well fluorescence microplate assay. When applied to the measurement of NADPH oxidase activation, the Amplex Red assay can detect H2O2 release from as few as 2000 phorbol myristate acetate-stimulated neutrophils with a sensitivity 5- to 20-fold greater than that attained in the scopoletin assay under the same experimental conditions. Furthermore, the oxidase-catalyzed assay using Amplex Red results in an increase in fluorescence on oxidation rather than a decrease in fluorescence as in the scopoletin assay. In comparison with other fluorometric and spectrophotometric assays for the detection of monoamine oxidase and glucose oxidase, this probe is also found to be more sensitive. Given its high sensitivity and specificity, Amplex Red should have a broad application for the measurement of H2O2 in a variety of oxidase-mediated reactions and very low levels of H2O2 in food, environmental waters, and consumer products. PMID- 9367499 TI - A one-step fluorometric method for the continuous measurement of monoamine oxidase activity. AB - We have developed a one-step fluorometric method for the measurement of monoamine oxidase (MAO) activity in 96-well microplates with sensitivity 10-fold higher than the conventional spectrophotometric assay method. This assay is based on the detection of H2O2 in a horseradish peroxidase-coupled reaction using N-acetyl-3, 7-dihydroxyphenoxazine (Amplex Red), a highly sensitive and stable probe for H2O2. With a single sampling, this assay is useful for performing both end-point and continuous measurements of MAO activity. Using a commercially available enzyme, our assay allows the detection of MAO B activity as low as 1.2 x 10(-5) U/ml. When applied to crude tissue homogenates, we have been able to selectively detect both MAO A and MAO B from cow brain tissue with protein content as low as 200 microgram per sample. The potential applications of this assay include the measurement of MAO activity in normal and diseased tissues, blood samples, and other biological fluids and the screening of drugs for the treatment of MAO mediated diseases. PMID- 9367500 TI - Cysteine-specific radioiodination of proteins with fluorescein maleimide. AB - A protocol is described for coupling of carrier-free iodine to protein sulfhydryl groups via fluorescein maleimide. 125I is first coupled to fluorescein maleimide in the presence of chloramine T. Iodination is stopped with sodium thiosulfate, and the iodine-substituted fluorescein maleimide is reacted with free cysteines of the protein. Excess label is then removed by gel-permeation chromatography. The procedure avoids exposition of the protein to oxidative conditions and does not require purification of the labeled carrier reagent. Suitability of the method for a given protein can be evaluated spectrophotometrically without employing radioactivity. It can be applied under denaturing conditions and may be particularly useful with mutant proteins carrying engineered single cysteine residues at sites that are not functionally critical. PMID- 9367501 TI - Comparison between microwell and bead supports for the detection of human cytomegalovirus amplicons by sandwich hybridization. AB - In this study, we compared the efficiency of capture DNA probes covalently bound onto magnetic beads or microplates for their hybridization with target human cytomegalovirus (HCMV) DNA amplicons. Polystyrene supports were first aminated by wet chemistry to allow covalent grafting of the capture probes. The level of amines grafted was three times higher on beads than on microwells. Increasingly higher sizes of capture probes were fixed on both supports and the best reaction yield ranged from 300 to 500 fmol. The sizes of the capture and detection probes were optimized in order to obtain high target DNA hybridization yield. Long capture probes were more accessible than short ones to the target, with faster kinetics of hybridization obtained on beads than on microplates. Sensitivity of the hybridization assay was then determined with a nonisotopic method and the detection limit found was 30 amol of HCMV amplicons on both supports. HCMV DNA extracted from clinical samples were amplified by PCR. The resulting amplicons were then analyzed using the optimized sandwich hybridization assay discussed here. The results perfectly fitted with the qualitative conclusions obtained after a nested PCR analyzed on agarose gel. PMID- 9367502 TI - Determination of the specific radioactivity of [14C]lactate by enzymatic decarboxylation and 14CO2 collection. AB - We present an enzymatic method for the determination of L-[14C]lactate specific radioactivity in complex biological samples containing other radiolabeled compounds. The method is based on the conversion of L-lactate to L-pyruvate by lactate oxidase (no EC number assigned) and the decarboxylation of L-pyruvate by pyruvate oxidase (EC 1.2.3.3). The 14CO2 produced by the enzymatic decarboxylation of pyruvate is quantitatively captured in a CO2 trap and its radioactivity is measured. The method is simple, specific, and precise (2% relative SD). It can be conveniently used for routine multiple determinations of L-[14C]lactate specific radioactivity in tracer metabolic studies. Under specified conditions, the method can also be used to determine the specific radioactivity of L-[14C]pyruvate. PMID- 9367503 TI - Free radical formation in reactions of lecithin with tetracyanoquinodimethane and tetracyanoethylene: relating the behavior of membrane-partitioned electrochemical cells to charge carrier using electron spin resonance. AB - Electron spin resonance spectra of solutions used to make conductive bilayer lipid membranes reveal that free radical formation is a precursor to membrane conductivity. Tetracyanoquinodimethane (TCNQ) forms a stable radical that self aggregates in nonaqueous media, yet will diffuse into the aqueous phase as a monomer, potentially allowing interfacial exchange. Tetracyanoethylene (TCNE) will undergo hydrolysis via a radical intermediate, and the decomposition product is ESR silent. The electrochemical response of an electrochemical cell partitioned by a membrane modified by these dopants is ionic for TCNE. Although the mechanism is less clear for TCNQ, the role of a stable radical is clearly implicated. PMID- 9367504 TI - Determination of serine hydroxymethyltransferase and reduced folate pools in tissue extracts. AB - Serine hydroxymethyltransferase (SHMT) from all sources tested catalyzes the slow exchange of the pro-2S proton of glycine with solvent protons. In the presence of tetrahydrofolate (H4PteGlun) this exchange rate is increased by about three orders of magnitude. This H4PteGlun-dependent exchange has been developed into a rapid and sensitive assay for both SHMT and H4PteGlun and the one-carbon derivatives of H4PteGlun. The procedure involves incubating [2-3H]glycine, H4PteGlun, and SHMT for 3 min followed by a separation of the exchanged protons in the solvent from the substrate glycine on a small Dowex-50 cation-exchange column at pH 2. In the presence of an excess of H4PteGlun the exchange rate is proportional to nanogram levels of SHMT. In the presence of an excess of SHMT the exchange rate is directly proportional to the concentration of H4PteGlun in the 0.1 to 1 pmol range. The concentration of one-carbon derivatives of H4PteGlun is determined by a preincubation of cell extracts with enzymes that convert each derivative into H4PteGlun. A complete reduced folate pool analysis of a tissue extract can be obtained in less than 2 h once a standard curve has been prepared for H4PteGlun. The method does not distinguish between mono- and polyglutamate forms of the coenzyme. PMID- 9367505 TI - A homogeneous, fluorescence polarization assay for src-family tyrosine kinases. AB - A nonradioactive, simple, sensitive fluorescence polarization assay was developed to assay protein tyrosine kinase activity. This assay involves incubation of a fluorescenylated peptide substrate with the kinase, ATP, and anti-phosphotyrosine antibody. The phosphorylated peptide product is immunocomplexed with the anti phosphotyrosine antibody resulting in an increase in the polarization signal as measured in a fluorescence polarization analyzer. Among several anti phosphotyrosine antibodies examined, monoclonal antibody PY54 was found to give the best polarization signal with the test peptide. For validation of the fluorescence polarization assay, Lck activity was compared with a 32PO4 transfer assay. In both the fluorescence polarization and 32PO4 transfer assays, Lck activity showed a similar dependence on ATP, Lck enzyme, and peptide substrate concentrations. Both assays gave similar inhibition constants with a known tyrosine kinase inhibitor staurosporine and the Lck inhibitor, 4-amino-5 (methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine. These results show that the fluorescence polarization assay can detect inhibitors and is comparable to the 32PO4 transfer assay. The fluorescence polarization method is advantageous compared to the 32PO4 transfer assay or ELISA or DELFIA because it is a one-step assay that does not involve several washings, liquid transfer, and sample preparation steps. It has the added advantage of using nonisotopic substrates. The fluorescence polarization assay thus is environmentally safe and minimizes handling problems. The homogeneous nature of the assay makes it readily adaptable to high-throughput screening for small-molecule drug discovery. PMID- 9367506 TI - A restriction fragment length polymorphism assay that differentiates human N acetyltransferase-1 (NAT1) alleles. AB - Currently there is much interest in the N-acetyltransferase-1 (NAT1) genetic polymorphism and its relationship to cancer. Previous studies have described methods to distinguish NAT1 alleles through polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) and/or allele-specific amplification. However, these methods detect at most only four of the NAT1 alleles identified in human populations. In this paper we describe a PCR-RFLP based assay that differentiates among eight human NAT1 alleles (NAT1*3, *4, *5, *10, *11, *14, *15, *16). This method should prove useful in molecular epidemiological studies investigating associations between NAT1 genotype and cancer. PMID- 9367508 TI - Simultaneous determination of creatinine, creatine, and guanidinoacetic acid in human serum and urine using liquid chromatography-atmospheric pressure chemical ionization mass spectrometry. AB - A rapid and direct method for simultaneous determination of creatinine, creatine, and guanidinoacetic acid in biological samples has been developed by using column liquid chromatography-mass spectrometry (LC/APCI-MS). The determinations of creatinine, creatine, and guanidinoacetic acid in the samples of human urine and serum were carried out by scanning the [M + H]+ ions of each compound. The recoveries of authentic compounds were 93.87 +/- 6.00% (n = 5) for creatinine, 94.80 +/- 8.93% (n = 5) for creatine, and 90. 92 +/- 7.96% (n = 5) for guanidinoacetic acid after ion-exchange resin treatment. The content of creatinine in human urine and serum was also measured by the Jaffe method, a common method of determination of creatinine currently used in hospitals. The contents of creatinine, creatine, and guanidinoacetic acid obtained using LC/APCI MS coincided well with those reported in previous papers. PMID- 9367507 TI - Semidry electroblotting of peptides and proteins from acid-urea polyacrylamide gels. AB - A semidry electrophoretic transfer method was developed for efficient electroblotting of proteins separated by acid-urea polyacrylamide gel electrophoresis (AU-PAGE). Model polypeptides ranging from 1.8 to 21.5 kDa were used to test transfer parameters that included time of transfer, power settings, transfer solutions, and membrane type. Optimized conditions were identified which allowed for transfer efficiencies of 70-100% following 5-15 min of applied current. The best transfer solution was 5% acetic acid, the same solvent used for electrophoresis. Therefore, acid-urea gels could be subjected to electrophoretic transfer without a soaking step, thereby reducing loss of band resolution and eliminating leaching of protein from the gel. The method was shown to be applicable to Western blot analysis of rat neutrophil defensins. PMID- 9367509 TI - Effect of three elution buffers on the recovery and structure of monoclonal antibodies. AB - Antibodies are routinely purified by acid/salt elution from antigen affinity columns. The antibodies recovered with this procedure are active, but the recovery of protein is often low. We investigated the effect of acid and other denaturing or chaotropic solvents on the conformation of monoclonal antibodies (mAbs) made against the extracellular region of Her2 receptor (sHer2) derived from Chinese hamster ovary cells. The mAb remain almost completely folded in the 0.1 M glycine, pH 2.9, commonly used for elution, with the beta-sheet secondary structure intact, and only very small changes detected in the environment of the tryptophans. In 7 M urea, 50 mM NaAc pH 4.0, the antibody was partially unfolded, with the Trp environment further perturbed and some of the beta-sheet structure converted to disordered structure. In 6 M guanidine HCl, 50 mM NaAc, pH 4.0, the antibody is completely unfolded, with no secondary or tertiary structure present. The antibodies exposed to glycine or urea were refolded by dialysis into phosphate-buffered saline (PBS), while the guanidine HCl-denatured antibodies were refolded by dialysis into 7 M urea, pH 4.0, followed by dialysis into PBS. The refolded antibodies were capable of forming antigen-antibody complexes which could be isolated by gel filtration chromatography. Two different mAbs were subjected to immunoaffinity chromatography on sHer2-Sepharose. mAb86 was eluted by 0.1 M Gly, pH 2.9, while mAb52 was eluted with the 7 M urea, 50 mM NaAc, pH 4.0. The isolated antibodies were refolded by dialysis into PBS, analyzed for their ability to recognize native sHer2 by immunoprecipitation, and denatured sHer2 by Western blot analysis. Both preparations recognized the native protein, but precipitated slightly different forms of sHer2, indicating that they might recognize different epitopes. The mAb52 is a more sensitive reagent for Western blot analysis. Thus, this procedure can be used to recover antibodies which would not be recovered with glycine as the only eluate. It is also possible that the antibodies can be fractionated by the different eluants into populations which can be used for different applications. PMID- 9367510 TI - Fractionation and characterization of polyclonal antibodies using three progressively more chaotropic solvents. AB - In the previous paper we described the effect of several different solvents on the structure of antibodies and demonstrated that 0.1 M glycine, pH 2.9, 7 M urea, pH 4.0, and 6 M guanidine-HCl, pH 4.0, unfold the antibodies to different degrees. Antibodies can be refolded from all of these solvents by dialysis. Polyclonal antibodies (pAbs) are a mixture of antibodies which recognize and bind different epitopes on the same antigen, with the strength of the antigen-antibody binding varying with each subpopulation. When rabbit antisera to the extracellular domain of Her2 receptor (sHer2), derived from Chinese hamster ovary cells, was applied to an antigen column, bound pAbs were recovered with a step wise elution of 0.1 M glycine, pH 2.9 (44% of the total recovered pAb), 7 M urea, pH 4.0 (29%), and 6 M guanidine-HCl, pH 4.0 (27%), with baseline resolution between them. Fluorescence spectra of the pAbs confirmed that the 0. 1 M glycine pH 2.9 sample had near-native structure, the pAbs in 7 M urea, pH 4.0, were partially unfolded, and the pAbs in the 6 M guanidine-HCl, pH 4.0, were totally unfolded. The glycine- or urea-eluted sample was refolded by dialysis into PBS, while the guanidine-HCl-eluted sample was first dialyzed into the 7 M urea pH 4.0 buffer and then into PBS. The refolded material from glycine or urea had native like spectra, while the spectrum of the protein refolded from 6 M guanidine-HCl was slightly perturbed. All three of these subpopulations of pAbs formed antigen antibody complexes which could be isolated by gel-filtration chromatography, precipitated sHer2 during immunoprecipitation, and recognized sHer2 in Western blots. The guanidine-HCl-eluted material was most sensitive for Western blotting. Identical results were obtained with pAbs applied either in the batch mode or to the top of the column, indicating that antibody aggregation which may occur when applied from the top of the column is not responsible for the distribution of pAbs into different subpopulations. These results indicate that the sequential use of these three increasingly chaotropic solvents to elute antibodies results in both increased recovery of antibodies and fractionation of pAbs into subpopulations with potentially different antigen binding characteristics. PMID- 9367511 TI - Production of mature human apolipoprotein A-I in a baculovirus-insect cell system: propeptide is not essential for intracellular processing but may assist rapid secretion. AB - To achieve expression of human mature apolipoprotein A-I (apoA-I) in the baculovirus-insect cell expression system, the propeptide encoding region of full length preproapoA-I was deleted using polymerase chain reaction and the resulting cDNA was cloned into BacPak8 plasmid. After transfection into Sf21 insect cells and plaque purification, mature human apoA-I was secreted by the infected cells into the medium as determined by immunoblotting, amino-terminal sequencing, and molecular weight determination. In both monolayer cell cultures, and in suspension cell culture, maximum expression was achieved by the fifth day. For the first 4 days, 50 to 70% of the synthesized apoA-I was retained in the cells. This intracellular apoA-I was represented by mature apoA-I as shown by immunoblotting and amino-terminal sequencing. Further incubation resulted in a sharp decrease in the cell apoA-I content without a corresponding increase in protein in the medium and most likely represents intracellular degradation of the protein. We conclude that the deletion of the propeptide, while not preventing the correct cleavage of prepeptide during intracellular processing, results in reduced secretion of mature apoA-I. The baculovirus-insect cell expression system described in this study provides a useful method for producing recombinant mature apoA-I and is a potential tool for understanding the function of propeptide in intracellular transport and secretion of apoA-I from cells. PMID- 9367512 TI - Purification of Wegener's granulomatosis autoantigen, proteinase 3, from neutrophils by Triton X-114 extraction of azurophilic granules. PMID- 9367513 TI - An evaluation of four staining methods for the detection of DNA in nondenaturing polyacrylamide gels. PMID- 9367514 TI - Production of single-stranded DNA using a uracil-N-glycosylase-mediated asymmetric polymerase chain reaction method. PMID- 9367515 TI - Quantitation of luciferase reporter mRNA by in vitro translation of total cellular RNA is faster and more sensitive than northern blotting and primer extension. PMID- 9367516 TI - A novel reporter gene MEL1 for the yeast two-hybrid system. PMID- 9367517 TI - Amplification and sequencing of end fragments from bacterial artificial chromosome clones by single-primer polymerase chain reaction. PMID- 9367518 TI - Direct ligation of human CD4 polymerase chain reaction fragment into vectors at specific restriction sites with positional heterostagger cloning. PMID- 9367519 TI - Algorithms for in vivo near-infrared spectroscopy. PMID- 9367520 TI - Specificity and target proteins of arginine-specific mono-ADP-ribosylation in T tubules of rabbit skeletal muscle. AB - In order to specify that protein labeling is the result of mono-ADP ribosylation, a careful evaluation of the reaction conditions and products is necessary. To investigate the specificity and target proteins of the arginine-specific mono-ADP ribosyltransferase (mADP-RT) in rabbit skeletal muscle T-tubules (TT) biotin- or digoxigenin-coupled NAD-derivatives were synthesized. They were used for the nonradioactive labeling of proteins and compared with radioactive mono-ADP ribosylation. According to the results of our studies, they cannot be used as substrates to detect arginine-specific or pertussis toxin-dependent mono-ADP ribosylation of target proteins in skeletal muscle. In contrast, radioactive NAD can be used to monitor these reactions. Under the appropriate reaction conditions, the radioactive [adenylate-14C]NAD and [32P]NAD were found to be solely consumed by the arginine-specific mADP-RT of skeletal muscle TT. The incorporation studies confirmed earlier data on the localization of the mADP-RT and its targets in TT. The T-tubular targets were purified in a single-step procedure using phenylboronate affinity chromatography. Of 18 target proteins delineated by autoradiography of electrophoretically separated T-tubular proteins, a 42-kDa protein was suggested to be the stimulatory G protein (Gsalpha). Mono-ADP-ribosylation of Gsalpha resulted in an inhibition of the T tubular adenylate cyclase activity as proven by the suppression of this inhibition using novobiocin as a specific inhibitor of mADP-RT. PMID- 9367521 TI - Differentiation status of cultured murine keratinocytes modulates induction of genes responsive to 2,3,7,8-tetrachlorodibenzo-p-dioxin. AB - Primary murine keratinocytes were cultured in a chemically defined, serum-free medium which facilitated manipulation of their differentiation status. Exposure of basal cell and differentiating cultures to >/= 0.1 nM 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) preferentially elevated 7-ethoxyresorufin O deethylase specific activities in differentiating cultures (28-fold versus 4-fold increases after 36 h of exposure). Semiquantitative reverse-transcription polymerase chain reaction (RT-PCR) analyses demonstrated the presence of constitutive mRNA transcripts corresponding to four known TCDD-inducible genes (e.g., Cyp1a1, Cyp1b1, Ahd4, and Nmo1) in both differentiating and proliferating cultures of murine keratinocytes. All four genes were induced in differentiating cultures following exposure to TCDD. No induction occurred in comparably treated basal cell cultures. Indirect immunofluorescence analyses demonstrated the presence of aryl hydrocarbon receptor (AHR) and aryl hydrocarbon receptor nuclear translocator (ARNT) proteins in both basal and differentiating keratinocytes. Both proteins appeared to be associated with the nucleus and their nuclear association was independent of prior exposure to TCDD. These studies suggest that AHR activation in murine skin is regulated as a function of the keratinocyte differentiation program. PMID- 9367522 TI - Nitric oxide modulates the activity of the hemoproteins prostaglandin I2 synthase and thromboxane A2 synthase. AB - Nitric oxide modulates the activity of the hemoprotein isomerase enzymes that transform prostaglandin H2 into prostaglandin I2 and thromboxane A2. Two nitric oxide donors, 1-hexanamine, 6-(2hydroxy-1-methyl-2-nitrosohydrazino)-N-methyl nitroso- hydrazine (MMNN) and 1,1-diethyl-2-hydroxy-2-nitrosohydrazine, modulated prostaglandin I2 synthase activity in a bidirectional manner. At moderate concentrations, they increased enzyme activity irreversibly and at higher concentrations they inhibited enzyme activity reversibly. We confirmed that these effects originated from nitric oxide. First, we showed that hemoglobin, a substance that sequesters nitric oxide, prevented both the activation and the inhibition of catalysis, stoichiometrically. Second, we showed that solutions depleted of nitric oxide had no effect on catalysis. Nitric oxide also modulated thromboxane A2 synthase activity; however, its effects on thromboxane A2 synthase differed from its effects on prostaglandin I2 synthase in three ways: (i) It inhibited thromboxane A2 synthase in a concentration-dependent manner. The IC50 = 4.2 +/- 0.8 microM MMNN corresponded to an IC50 congruent with 0.1-0.3 microM nitric oxide. (ii) It did not increase thromboxane A2 synthase activity at any concentration tested. (iii) Its irreversible inhibition of thromboxane A2 synthase contrasted with its reversible inhibition of prostaglandin I2 synthase. Nitric oxide also inhibited cellular formation of thromboxane A2 by intact platelets in a concentration-dependent manner. The IC50 = 267 +/- 26 microM MMNN corresponded to an IC50 congruent with 6-18 microM nitric oxide. We conclude that nitric oxide can modulate certain hemoprotein enzymes in the biosynthetic cascade that governs the formation of eicosanoid mediators of thrombosis and hemostasis. PMID- 9367523 TI - Biological oxidations and P450 reactions. Recombinant mouse CYP1B1 expressed in Escherichia coli exhibits selective binding by polycyclic hydrocarbons and metabolism which parallels C3H10T1/2 cell microsomes, but differs from human recombinant CYP1B1. AB - Orthologs of a previously identified CYP1B subfamily designated CYP1B1, which are constitutively expressed in mammary, uterine, and embryonic cells, have previously been functionally linked to 7,12-dimethylbenz-a-anthracene (DMBA) metabolism. A chimeric construct of mouse CYP1B1 in which the 20 NH2-terminal amino acids have been replaced by eight residues from human CYP17 has been expressed in Escherichia coli. This recombinant mouse CYP1B1 (recCYP1B1m) exhibited DMBA metabolism accurately reproducing the characteristic product distribution and specific activity of 3.4 nmol/nmol P450/min seen in C3H10T1/2 cells from which this cDNA has been cloned. The high proportion of 10,11- and 3,4 dihydrodiols and near absence of 5,6-dihyrodiol- and 7-hydroxy-DMBA metabolites are seen only in rodent microsomes where CYP1B1 is highly expressed. This distribution of products from recCYP1B1m was highly dependent on addition of epoxide hydrolase, particularly the ratio of 3,4-dihydrodiol to 4-phenol metabolites. These characteristics in addition to inhibition by antibodies raised to recCYP1B1m establish that the CYP1B1 cDNA indeed encodes the P450 responsible for polycyclic aromatic hydrocarbon (PAH) metabolism from C3H10T1/2 cells. DMBA metabolites from cDNA-expressed human CYP1B1 (recCYP1B1h) however, exhibited a different regioselectivity toward DMBA resembling human CYP1A1 catalyzed DMBA metabolism. Reconstitution of recCYP1B1m with different concentrations of NADPH P450 reductase indicated a high affinity interaction with an apparent Km of 3 nM. Large PAH such as benz[a]pyrene, benz[e]pyrene, benz[a]anthracene, DMBA, 3 methylcholanthrene, and 1-ethynylpyrene bound to recCYP1B1m with high affinity (Kd 0.08 to 0.22 microM) concomitant with substantial spectral shifts (40% low to high spin state change). Smaller PAHs like pyrene, phenanthrene, and naphthalene neither produced spectral changes nor inhibited the spectral change caused by benz[a]pyrene. Among tested steroids, progesterone bound weakly to recCYP1B1m (Kd > 20 microM) with a comparable spectral shift and was a weak inhibitor of DMBA metabolism, but was not metabolized. While 17beta-estradiol is a substrate for human CYP1B1 we have found no evidence for binding to mouse CYP1B1. This data establishes CYP1B1 as an important contributor to activation of PAHs, particularly in extra hepatic tissues that are susceptible to cancer where CYP1B1 in contrast to CYP1A1 is constitutively expressed. PMID- 9367524 TI - A dominant negative mutation in Saccharomyces cerevisiae methionine aminopeptidase-1 affects catalysis and interferes with the function of methionine aminopeptidase-2. AB - Methionine aminopeptidase (MetAP) enzymes require the metal ion cobalt, but little is known about the role of cobalt in the structural stability or catalysis of these enzymes. In Escherichia coli MetAP, for which a crystal structure is available, the five amino acid residues liganding the two cobalt ions are Asp97, Asp108, His171, Glu204, and Glu235. These five amino acids are conserved in all MetAPs sequenced to date. The C-terminal domain of the yeast Saccharomyces cerevisiae MetAP1 is 41% identical to E. coli MetAP and contains these cobalt coordinating residues. Using site-directed mutagenesis on the gene coding for yeast MetAP1, we replaced Asp219 (corresponding to Asp97 in E. coli MetAP) with Asn. The yeast D219N mutant enzyme has 10(3)-fold lower catalytic activity and a different substrate specificity when compared to wild-type yeast MetAP1. These results indicate that the side-chain of Asp219 is important for catalysis. Expression of D219N-MetAP1 in yeast causes a slow-growth phenotype and interferes with wild-type MetAP1 in a dominant manner. Expression of D219N-MetAP1 also affects the function of S. cerevisiae MetAP2. PMID- 9367525 TI - Determination of the amino acid sequence of the plant cytolysin enterolobin. AB - The cytolytic seed protein enterolobin from seeds of Enterolobium contortisiliquum was purified by using FPLC on a Mono Q column giving a single peak in capillary electrophoresis. The complete amino acid sequence of the plant cytolysin was determined by an automated method, yielding a molecular mass of 54,806 Da. Databank searches and sequence alignment demonstrated a high degree of sequence identity and similarity between enterolobin and bacterial aerolysins from Aeromonas hydrophila and A. sobria. Several key residues involved in oligomerization of A. hydrophila aerolysin are conserved in enterolobin. Circular dichroism measurements and structural predictions revealed that enterolobin is very rich in beta sheet, like aerolysin. Light-scattering studies revealed that enterolobin oligomerizes as a hexamer at pH levels below 7.0. NaCl concentrations above 50 mM caused dimerization of enterolobin. Dithiothreitol did not cause oligomerization. PMID- 9367526 TI - Immunoblot analyses of the elicited Sanguinaria canadensis enzyme, dihydrobenzophenanthridine oxidase: evidence for resolution from a polyphenol oxidase isozyme. AB - In our initial purification of dihydrobenzophenanthridine oxidase from Sanguinaria canadensis plant cell cultures, we reported that our most purified preparations contained a major band at 77 kDa and minor lower Mr bands. Here we present evidence on highly purified dihydrobenzophenanthridine oxidase from elicited S. canadensis cultures to indicate that this enzyme is the 77-kDa protein and that lower Mr bands include an isozyme(s) of the polyphenol oxidase family that copurifies with it. An antibody raised against the 77-kDa protein and an anti-polyphenol oxidase antibody that recognizes a 70-kDa band were used to monitor chromatographic fractions by immunoblot analysis of the oxidases. Oxidase containing eluates from DEAE-Sephadex, CM, and HiTrap blue were compared to corresponding flow-through fractions. Bands at 77 and 88 kDa were detected with anti-dihydrobenzophenanthridine oxidase antibody in eluates displaying high dihydrobenzophenanthridine oxidase activity. Polyphenol oxidase specific activity and immunoreactivity partitioned both in flow-through and eluate fractions of the CM and HiTrap columns. Estimation of the dihydrobenzophenanthridine oxidase and polyphenol oxidase specific activities for each step showed increasing enrichment of alkaloidal enzyme accompanied by variable dihydrobenzophenanthridine oxidase/polyphenol oxidase activity ratios. Taken together these observations indicate that the dihydrobenzophenanthridine and polyphenol oxidases have Mr values of 77 and 70 kDa, respectively, and the two enzymes are different entities. PMID- 9367527 TI - Spectroscopic study of secondary structure and thermal denaturation of recombinant human factor XIII in aqueous solution. AB - The secondary structure and thermal denaturation (in H2O vs D2O) of recombinant human factor XIII in aqueous solutions were investigated using infrared and circular dichroism (CD) spectroscopies. The infrared amide I spectrum of the protein in H2O solution at 25 degrees C exhibited an absorbance maximum near 1642 cm-1, indicating the presence of a predominantly beta-sheet structure. Quantitative analysis revealed that the native protein contains 13-16% alpha helix, 41-49% beta-sheet, 29% beta-turn, and 10-14% extended strand structures. The presence of a strong low-wavenumber beta-sheet band at 1641 cm-1 and a weak high-wavenumber beta-sheet band at 1689 cm-1 indicated that the beta-sheet structure of the protein is predominantly antiparallel. Quantitative analysis of the CD spectrum using the SELCON method indicated a secondary structural content of 10% alpha-helix, 40-50% beta-sheet, 20-35% beta-turns, and 20-35% unordered elements, which matches that determined by X-ray crystallography. The apparent discrepancy with the contents of unordered element determined by infrared spectroscopy is reconciled by considering that CD spectroscopy and X-ray crystallography assign extended loops and strands to unordered elements, whereas infrared spectroscopy recognizes these as distinct structured elements. During heating above 60 degrees C, a pair of new infrared bands appeared at 1626 and 1693 cm-1 for the protein in H2O and 1619 and 1683 cm-1 in D2O, indicating a formation of intermolecular beta-sheet aggregates. The intensities of the new bands increased as a function of temperature, concomitant with an intensity decrease in bands for the native protein structural elements. As expected, there was an increase in thermal stability in D2O relative to that in H2O, which was manifested as an increase of about 5 degrees C in the temperature for initial loss of infrared bands assigned to native structural elements and for appearance of bands due to intermolecular beta-sheet. In addition, the midpoint of the thermally induced transitions in infrared spectra were about 2.5 degrees C higher in D2O than in H2O. Based on the infrared analysis, the thermally denatured state of the protein in both H2O and D2O contains predominantly intermolecular beta sheet. The broad, poorly resolved absorbance that spans the region between the intermolecular beta-sheet bands was assigned to an ensemble of heterogeneous structural elements (including unordered), none of which is populated to a high enough degree to result in a distinct infrared band. Results from CD spectroscopy support these conclusions about the structure of the denatured, aggregated protein. PMID- 9367528 TI - Catalytic properties of NAD(P)H:quinone oxidoreductase-2 (NQO2), a dihydronicotinamide riboside dependent oxidoreductase. AB - Human NAD(P)H:quinone acceptor oxidoreductase-2 (NQO2) has been prepared using an Escherichia coli expression method. NQO2 is thought to be an isoform of DT diaphorase (EC 1.6.99.2) [also referred to as NAD(P)H:quinone acceptor oxidoreductase] because there is a 49% identity between their amino acid sequences. The present investigation has revealed that like DT-diaphorase, NQO2 is a dimer enzyme with one FAD prosthetic group per subunit. Interestingly, NQO2 uses dihydronicotinamide riboside (NRH) rather than NAD(P)H as an electron donor. It catalyzes a two-electron reduction of quinones and oxidation-reduction dyes. One-electron acceptors, such as potassium ferricyanide, cannot be reduced by NQO2. This enzyme also catalyzes a four-electron reduction, using methyl red as the electron acceptor. The NRH-methyl red reductase activity of NQO2 is 11 times the NADH-methyl red reductase activity of DT-diaphorase. In addition, through a four-electron reduction reaction, NQO2 can catalyze nitroreduction of cytotoxic compound CB 1954 [5-(aziridin-1-yl)-2,4-dinitrobenzamide]. NQO2 is 3000 times more effective than DT-diaphorase in the reduction of CB 1954. Therefore, NQO2 is a NRH-dependent oxidoreductase which catalyzes two- and four-electron reduction reactions. NQO2 is resistant to typical inhibitors of DT-diaphorase, such as dicumarol, Cibacron blue, and phenindone. Flavones are inhibitors of NQO2. However, structural requirements of flavones for the inhibition of NQO2 are different from those for DT-diaphorase. The most potent flavone inhibitor tested so far is quercetin (3,5,7,3',4'-. 6pentahydroxyflavone). It has been found that quercetin is a competitive inhibitor with respect to NRH (Ki = 21 nM). NQO2 is 43 amino acids shorter than DT-diaphorase, and it has been suggested that the carboxyl terminus of DT-diaphorase plays a role in substrate binding (S. Chen et al., Protein Sci. 3, 51-57, 1994). In order to understand better the basis of catalytic differences between NQO2 and DT-diaphorase, a human NQO2 with 43 amino acids from the carboxyl terminus of human DT-diaphorase (i.e., hNQO2-hDT43) has been prepared. hNQO2-hDT43 still uses NRH as an electron donor. In addition, the chimeric enzyme is inhibited by quercetin but not dicumarol. These results suggest that additional region(s) in these enzymes is involved in differentiating NRH from NAD(P)H. PMID- 9367529 TI - Histone-tryptase interaction: H2A N-terminal tail removal and inhibitory activity. AB - The involvement of tryptase, the trypsin-like serine proteinase of mast cell granules, in many (patho)physiological conditions is now recognized. In vitro this enzyme is known to act as a potent growth factor for fibroblasts and epithelial cells. Moreover, a role in inflammatory diseases and in dermatological disorders characterized by increased cell turnover has been suggested for this protease. In an attempt to understand the molecular basis of tryptase activity, we have investigated the interaction in vitro between bovine tryptase and histones. Here we show that tryptase cleaves histone H2A at a specific site (Arg20-Ala21), resulting in the removal of the N-terminal flexible fragment of the molecule. Furthermore, we demonstrate that the H2A major fragment (H2A*, 109 residues) generated by hydrolysis and lacking the N-terminal domain, is a noncompetitive, reversible and highly specific inhibitor (Ki = 29 nM) of tryptase enzymatic activity. H2A* is able to inhibit the hydrolysis of a small substrate as well as the cleavage of fibronectin, a high-molecular-weight substrate of tryptase. PMID- 9367530 TI - Comparison of oxygen radical generation from the reductive activation of doxorubicin, streptonigrin, and menadione by xanthine oxidase and xanthine dehydrogenase. AB - Investigations into the enzymes responsible for the reductive activation of antineoplastic agents are of particular interest with regard to the use of these agents in the treatment of solid tumors. Xanthine oxidase (EC 1.1.3.22; XO) and xanthine dehydrogenase (EC 1. 1.1.204; XDH) are two enzymes capable of the reductive activation of antineoplastic agents. Previously, XDH, the enzymatic precursor of XO, was not extensively studied because of difficulties in its isolation. Research in the reductive activation of antineoplastic agents by XDH has increased with the discovery of a rapid and high-yield purification procedure for XDH. In the present investigation, the potential for drug activation of doxorubicin (DOX), streptonigrin (STN), and menadione (MD) by XO and XDH was assessed through oxygen consumption studies. These studies were conducted at pH 7.4 and pH 6.0 to reflect physiological and the acidic pH of solid tumors, respectively. Apparent kinetic constants were determined for DOX, STN, and MD activation by XO and XDH at both pH levels. Higher oxygen consumption was observed for XDH drug activation in comparison to XO drug activation at equivalent enzyme activity for both pH levels. Drug-induced oxygen consumption was affected by pH. Hence, drug activation for DOX, STN, and MD was dependent upon the form of the xanthine-converting enzyme and the pH. PMID- 9367531 TI - Stimulation of the ferroxidase activity of ceruloplasmin during iron loading into ferritin. AB - Ceruloplasmin purified from horse serum was rapidly reduced upon addition of increasing equivalents of ferrous iron, generating an electronically and conformationally distinct form. This form of ceruloplasmin was characterized by significant (80%) loss of EPR detectable type I and type II copper(II), complete loss of visible absorbance at 610 nm, as well as decreased hydrophobic surface area. The reduced form of ceruloplasmin slowly reduced molecular oxygen to complete its catalytic cycle. The presence of varied concentrations of apoferritin, but not apotransferrin, significantly enhanced the rate of ceruloplasmin oxidation. The magnitude of this stimulatory effect increased as the molar ratio of ceruloplasmin to apoferritin approached 1.0, shown previously to be the optimum ratio for loading iron into ferritin. The rate of ferrous iron oxidation by ceruloplasmin was significantly stimulated by the presence of apoferritin; however, apotransferrin had no effect. The length of time required for ceruloplasmin to oxidize all the iron and return to the native form of the enzyme was also affected by the concentration of iron. In addition, the rate of iron loading into ferritin was dependent upon ferrous iron concentration. These results provide evidence for the formation of a specific complex between the reduced form of ceruloplasmin and apoferritin and that reduction of ceruloplasmin by ferrous iron may be the signal for complex formation. PMID- 9367533 TI - Manganic porphyrins possess catalase activity and protect endothelial cells against hydrogen peroxide-mediated injury. AB - Manganic porphyrins are redox active metal complexes that have been employed as superoxide dismutase mimics. We tested whether these metalloporphyrins could also dismute hydrogen peroxide (H2O2) and whether they could protect endothelial cells against H2O2. Both of the manganic metalloporphyrins tested were found to catalytically dismute H2O2. These manganic porphyrins also protected endothelial cells in dose-dependent manners against H2O2-mediated injury with MnTMPyP having an EC50 of 8 microM and MnTBAP having an EC50 of 15 microM. The zinc containing analogs of these porphyrins were inactive in dismuting H2O2 and did not protect. These studies further define the antioxidant capacity of metalloporphyrins in converting superoxide to H2O2 and H2O2 to water. These data suggest that manganic porphyrins may be useful therapeutics against disease states associated with the overproduction of reactive oxygen species. PMID- 9367532 TI - 4-Coumaroyl coenzyme A 3-hydroxylase activity from cell cultures of Lithospermum erythrorhizon and its relationship to polyphenol oxidase. AB - A 4-coumaroyl-CoA 3-hydroxylase activity was purified 4600-fold from cell cultures of Lithospermum erythrorhizon. The enzyme showed a molecular mass of 42,400 +/- 1700 Da in gel chromatography and required ascorbate, NADH, or NADPH as cofactors. 4-Coumaroyl-CoA, 4-coumarate, p-cresol, and several other phenolic substances, but not tyrosine, were accepted as substrates for the hydroxylation. Besides hydroxylase activity, the enzyme showed diphenol oxidase activity. Both activities were inhibited by diethyldithiocarbamate or beta-mercaptoethanol, although at different concentrations. The enzyme showed striking similarity to a 4-coumaroyl-glucose 3-hydroxylase from sweet potato (Ipomoe batatas) roots, which has reportedly been purified to homogeneity and identified as a specific enzyme of chlorogenic acid biosynthesis. Close examination and comparison to a commercially available polyphenol oxidase, however, suggest that the enzyme activities purified from both Lithospermum and sweet potato are polyphenol oxidases rather than specific enzymes of secondary metabolism. PMID- 9367534 TI - Immunoaffinity method to identify aggregin, a putative ADP-receptor in human blood platelets. AB - The ADP-receptor on the surface of human platelets and cells of megakaryocytic lineage has been classified as P2T purinergic receptor for which ADP is an agonist and ATP is an antagonist. Although it is one of the earliest identified of the important cellular receptors, it has neither been purified nor cloned. We have developed an immunoaffinity method for rapidly identifying the platelet ADP receptor and this method can be extended to the purification of the receptor. A polyclonal antibody to glutamate dehydrogenase (GDH) covalently modified by 5'-p fluorosulfonylbenzoyladenosine (FSBA) recognized neither FSBA nor glutamate dehydrogenase. Immunoblot of the gel obtained by sodium dodecyl sulfate polyacrylamide gel electrophoresis of solubilized FSBA-labeled platelets showed the presence of a protein band at 100 kDa and this band was absent in the immunoblots of platelets that were preincubated with ADP and ATP or covalently modified by the chemically reactive ADP-affinity analogs, 2- and 8-(4-bromo-2,3 dioxobutylthio)adenosine-5'-diphosphate (2- and 8BDB-TADP) and 2-(3-bromo-2 oxopropylthio)adenosine-5'-diphosphate (2-BOP-TADP), prior to treatment with FSBA. FSBA as well as 2- and 8-BDB-TADP and 2-BOP-TADP have been previously shown to inhibit ADP-induced platelet responses by selectively and covalently modifying aggregin (100 kDa), an ADP-receptor in intact human blood platelets. The results show that polyclonal antibody to FSBA-labeled GDH is capable of recognizing FSBA labeled aggregin on platelets and, thus, could be used to purify aggregin by immunoaffinity column chromatography. The immunoaffinity method was found to be far more sensitive than the radiochemical methods to identify aggregin previously developed in our laboratory. Since FSBA is also capable of reacting with enzymes that require ATP for their catalytic function, the polyclonal antibody may be used to identify and purify other P2-type purinergic receptors that require binding of ATP before eliciting cellular responses. PMID- 9367535 TI - Superoxide imposes leakage of sulfite from Escherichia coli. AB - Escherichia coli, which lacks the cytosolic superoxide dismutases, exhibits several nutritional auxotrophies when growing aerobically. The cysteine/methionine requirement, which is one of these, was previously shown to be due to leakage from the cells, and accumulation in the medium, of a metabolic intermediate on the biosynthetic route to these amino acids. The parental strain does not significantly accumulate this compound. It is now shown that treatment with alkaline cyanide releases sulfite from this compound, a property shared by alpha-hydroxy sulfonic acids (carbonyl-bisulfite adducts). Since E. coli accumulates carbonyl compounds in the growth medium, it appears likely that the sulfitogenic compounds accumulated by the sodA sodB strain are alpha-hydroxy sulfonic acids. PMID- 9367536 TI - Effect of replacement of the amino and the carboxyl termini of rat testis fructose 6-phosphate, 2-kinase:fructose 2,6-bisphosphatase with those of the liver and heart isozymes. AB - Fru 6-P,2-kinase:Fru 2,6-Pase is a bifunctional enzyme, consisting of highly conserved catalytic domains and variable regulatory domains. The regulatory domains reside in either the N- or the C-terminus, depending upon the isozyme. The rat testis enzyme (RT2K) lacks the regulatory domain, but the rat liver and the bovine heart enzymes contain phosphorylation site(s) in the N- and the C termini, respectively. In order to determine whether the regulatory domains can be swapped, we have constructed mutant enzymes in which the N- or the C-terminal tail of the testis enzyme was replaced with that of either the liver or the heart enzyme. The substitution with the N-terminus of the liver enzyme (RLN-RT2K) resulted in a small change in the kinetic properties of Fru 6-P,2-kinase, but that with the heart enzyme increased the KFru 6-P 18-fold without affecting the Vmax. The substitution with the C-terminus of the heart enzyme had little effect. The phosphorylation of RLN-RT2K increased KFru 6-P fivefold as in the liver enzyme but did not affect the Fru 2,6-Pase, unlike the liver enzyme. All these mutant enzymes were more thermally labile than the wild type testis enzyme. RLN RT2K was more sensitive to the denaturant. These results suggest that the N terminus of the liver enzyme could interact with the kinase domain of the testis enzyme, regulating the kinase activity but was unable to affect the phosphatase domain. These differences could be explained by the large differences in net charges of the terminal tails. PMID- 9367537 TI - Interaction of nitric oxide with 2-thio-5-nitrobenzoic acid: implications for the determination of free sulfhydryl groups by Ellman's reagent. AB - Nitric oxide (NO) in an aerobic environment, reacts with the sulfhydryl groups of proteins to form nitroso thiols. Ellman's reagent, 5,5'-dithiobis(2-nitrobenzoic acid), DTNB, is widely used for the determination of -SH groups. In this procedure, DTNB, a symmetric aryl disulfide, reacts with the free thiol to give a mixed disulfide plus 2-nitro-5-thiobenzoic acid (TNB) which is quantified by its absorbance at 412 nm. We observed that the presence of NO during the determination of SH groups in a reaction system containing glutathione (GSH) or bovine serum albumin (BSA) plus DTNB resulted in an inhibition in the detection of TNB. Addition of NO donors or NO gas after TNB was already formed led to the bleaching of yellow color and loss of absorbance at 412 nm. These interactions did not occur under anaerobic conditions. Decreased formation of TNB therefore appeared to be due not only to destruction of SH groups of BSA or GSH by NO (S nitrosation) and consequently to lower TNB formation, but also to direct reaction of NO/O2 with TNB. The mechanism(s) of inhibition of accumulation of TNB by NO was evaluated. NO generated by DEA/NO, SNAP, or spermine/NO, as well as gaseous NO or BSA-NO, directly interacted with TNB, followed by decreased absorbance at 412 nm in a concentration- and time-dependent manner. Kinetics of NO/O2 interaction with TNB were dependent on the ability of the NO donors to release NO as the donors with a short half-life bleached the yellow color of TNB faster. The requirement for O2 suggests that nitrogen oxide or higher oxides of NOx are responsible for interaction with TNB. The UV/VIS spectrum of the final product formed during the interaction of NO with TNB was identical to that of DTNB. These results suggest that interaction of NO (NOx) with TNB resulted in the formation of an unstable nitrosothiol, followed by oxidation and dimerization back to the corresponding disulfide, DTNB. Therefore, determination of SH groups in proteins by Ellman's reagent after or in the presence of NO treatment is complicated since the reduced form of DTNB, TNB, can be reoxidized by NO back to DTNB, with subsequent loss of absorbance at 412 nm. PMID- 9367538 TI - Standardization and calibration of cytokine immunoassays: meeting report and recommendations. PMID- 9367539 TI - Molecular characterization of the human interleukin (IL)-17 receptor. AB - Human interleukin 17 (hIL-17) is a T-cell derived cytokine that exhibits 63% amino acid sequence identity to mouse IL-17 (mIL-17) and 57% identity to a viral protein encoded by the herpesvirus saimiri (HSV) gene 13 (HVS13). The IL-17 family of proteins binds to a unique mouse receptor (mIL-17R). Using nucleic acid hybridization techniques, a cDNA encoding a human homologue of the mIL-17R (hIL 17R) was isolated from a human T cell library. The predicted amino acid sequence of the hIL-17R is 69% identical to the mIL-17R, shares no homology with previously identified cytokine receptor families, and exhibits a broad tissue distribution. The hIL-17R gene was localized to chromosome 22. Monoclonal antibodies (mAbs) generated against the hIL-17R were able to block the IL-17 induced production of cytokine from human foreskin fibroblast (HFF) cells. Binding studies suggest that recombinant hIL-17 binds to the hIL-17R with low affinity. PMID- 9367540 TI - Tumour necrosis factor-induced necrosis versus anti-Fas-induced apoptosis in L929 cells. AB - Murine fibrosarcoma L929 cells were transfected with human Fas cDNA. The mode of cell death was analysed following treatment either with tumour necrosis factor (TNF) or with agonistic antibodies to Fas. While triggering of the TNF receptors led to necrosis, clustering of the Fas antigen resulted in apoptotic cell death. N-tosyl-l-phenylalanine chloromethyl ketone and Nalpha-p-tosyl-l-lysine chloromethyl ketone, two serine protease inhibitors, has a protective effect on TNF-induced killing, while Fas-mediated cell death was rather enhanced. Lithium chloride, which had a synergistic effect on TNF cytotoxicity, did not affect Fas mediated death, whereas staurosporine had an enhancing effect on both types of cell death. Aphidicolin and hydroxyurea, inhibitors of DNA synthesis, were able to sensitize cells to Fas-induced killing, but had no effect on TNF cytotoxicity. Finally, we demonstrate that the effect of increasing concentrations of actinomycin D or cycloheximide is very different for the two types of cell killing. We conclude that either necrosis or apoptosis can occur in the same cell type, depending on the trigger, and that, although both pathways perhaps may share some cellular components, signal transduction is different for the two types of cell death. PMID- 9367541 TI - Correlation between the release of IL-2 and granule-associated DNase activity in human lymphomononuclear cells stimulated with immunomodulating peptides and proteins. Role of different antigen-presenting cells. AB - The authors have already described that a series of short peptides, modelled after sequences related to human extracellular matrix (ECM) proteins and sharing some common structural features, activate Th1 clones through a process involving peptide presentation in HLA-DR proteins. Those peptides induce also LAK- and NK dependent cytotoxicity as well as activation of monocytes/macrophages present in human peripheral blood mononuclear cell (PBMC) populations. The release of interleukin 2 (IL-2) and interferon gamma (IFN-gamma) by Th cells present in PBMC depleted of macrophages, or B cells is reported, after incubation in the presence of those peptides, fibronectin or Staphylococcus aureus protein A. The authors found that all the molecules tested needed at least the presence of a type of antigen-presenting cell (APC) to exert their stimulatory effect. Some peptides seem to be preferentially presented to Th cells by B cells, while others seem to depend on monocyte/macrophages for this presentation. The dependence on one or another APC seems to be due to differences in the sequences of these peptides. The immunomodulatory agents studied also gave rise to a clear increase in a DNase activity associated with secretion granules of PBMC. That there is a correlation between the release of IL-2 and this DNase activity when using a complete PBMC population, B cell-depleted PBMC or macrophage-depleted PBMC stimulated with the peptides tested has been found. PMID- 9367542 TI - Adenovirus-mediated gene transfer in rat liver of interleukin 4 but not interleukin 10 produces severe acute hepatitis. AB - Several immune responses are either limited to or concentrated in a given organ. Cytokines produced during ongoing immune responses have organ-localized effects that can be only partially mimicked upon their systemic delivery. Recombinant adenoviruses are efficient vectors to induce transient organ-localized cytokine expression. This allows in vivo analysis of the effects of cytokines produced spatially and temporally in a manner comparable to that observed during immune responses. The authors generated recombinant adenovirus for rat IL-4 (AdIL-4) and IL-10 (AdIL-10) to analyse the in vivo effects of these two important immunoregulatory molecules after gene transfer in the liver. It was first established that AdIL-4 and AdIL-10 were able to direct the production of biologically active cytokines by different rat cell types in vitro. Intraportal injection of doses of up to 10(10) pfu of AdIL-10 or control non-coding recombinant adenovirus were well tolerated, and hepatic histology showed only mild alterations. Conversely, animals receiving more than 2.5 x 10(9) pfu of AdIL 4 showed dose-dependent mortality, with clinical signs of hepatic dysfunction. Liver histology in animals receiving 2.5 x 10(9) pfu of AdIL-4 showed severe acute hepatitis with maximal lesions between day 7 and 14 and almost complete normalization by day 28 after gene transfer. The leukocyte infiltrate was composed primarily of mononuclear cells, but eosinophils and mast cells were significantly increased as compared to control animals. Hepatic function was also altered in animals that received AdIL-4, with kinetics similar to that of histological lesions. Our study describes a model for investigating cytokine function in vivo through liver-localized transgene expression mediated by adenoviral vectors and demonstrates that liver production of IL-4 but not IL-10 results in acute severe hepatitis. PMID- 9367543 TI - Tumour necrosis factor alpha binding to human and mouse trophoblast. AB - Tumour necrosis factor alpha (TNF-alpha) is a cytokine with pleiotropic effects, modulating cell growth, differentiation, and synthesis of various substances. Recent demonstration of TNF-alpha mRNA and protein in the uteroplacental unit suggests that this cytokine may be involved in the development of the embryo. To determine whether the embryo itself binds TNF-alpha, mouse blastocyst outgrowths and human first trimester villous trophoblast were analysed for TNF-alpha binding. Our experiments revealed that binding of TNF-alpha could be specifically detected on the trophectoderm of the outgrowing mouse embryos. They also show a complete disappearance of the colony-stimulating factor 1 (CSF-1) receptor that occurs shortly after the binding of TNF-alpha by the trophectoderm. In human first trimester villous trophoblast, TNF-alpha binding was found to be predominantly detectable on the syncytiotrophoblast and to a lesser extent on the cytotrophoblastic cells. Binding was not observed on adjacent embryonic or maternal cells. Our results further support the idea that TNF-alpha as well as other cytokines may modulate early embryonic development and implantation. PMID- 9367544 TI - Induction of cytokines in cynomolgus monkeys by the immune response modifiers, imiquimod, S-27609 and S-28463. AB - Imiquimod, S-27609 and S-28463 are imidazoquinolines known to have antiviral and antitumour properties mediated by the induction of cytokines, in particular interferon alpha (IFN-alpha). This study evaluated these compounds for their ability to induce cytokines and cytokine specific messenger RNAs (mRNA) in cynomologus monkeys (Macaca fascicularis). Peripheral blood mononuclear cell (PBMC) cultures from monkeys produced IFN, interleukin 1beta (IL-1beta), IL-6 and IL-8 after treatment with imiquimod, S-27609 and S-28463. Tumour necrosis factor alpha (TNF-alpha) was also increased in cultures stimulated with S-27609 or S 28463. Monkey PBMCs stimulated with imiquimod, S-27609 and S-28463 showed increased mRNA levels of IFN-alpha, IL-1alpha, IL-6 and the IFN inducible protein, MxA above those seen in untreated cultures. S-27609 and S-28463 also had higher TNF-alpha mRNA expression than cultures not receiving drugs. When compared to lipopolysaccharide (LPS), S-27609 was less effective at inducing IL-1beta, IL 6, IL-8 and TNF-alpha but induced higher concentrations of IFN. Similar results were seen when evaluating cytokine mRNA levels. Upon oral administration to monkeys, S-28463 stimulated a dose-dependent increase in serum concentrations of IFN, TNF-alpha, IL-1 receptor antagonist (IL-1Ra) and IL-6, while imiquimod induced increases in IFN and IL-1Ra concentrations. Finally, skin biopsies from monkeys treated topically with S-28463 had increases over baseline in mRNA for IFN-alpha, IL-1alpha, IL-6 and MxA protein. The data show that imidazoquinolines induce cytokines and cytokine specific mRNA in cynomolgus monkeys. These results demonstrate the usefulness of human amplimers and human ELISAs in the detection of cytokine specific mRNAs and proteins in cynomolgus monkeys. PMID- 9367545 TI - Interleukin-12-mediated killer activity in lung cancer patients. AB - The authors investigated the interleukin (IL)-12-inducible killer activity of blood mononuclear cells (MNC) from 30 untreated primary lung cancer patients and 24 control subjects. Cytotoxicity was assayed as 4-h 51Cr release from Daudi lymphoma cells or lung cancer cells (H-69, N-291 and PC-9). MNC from lung cancer patients exhibited similar killer activity to those from control subjects after in vitro incubation with IL-12 for 4 days. Effective killer induction by IL-12 was observed even in MNC from advanced lung cancer patients and patients with small cell lung cancer. IL-12 and a suboptimal dose of IL-2 had additive effects in inducing killer activity in MNC from both lung cancer patients and control subjects. On the other hand, with an optimal dose of IL-2, IL-12 suppressed killer induction. Addition of IL-12 alone or in combination with IL-2 resulted in interferon (IFN)-gamma production by MNC from lung cancer patients as well as control subjects. These observations suggest that IL-12 could be useful for immunotherapy of lung cancer in humans. PMID- 9367546 TI - Increased serum IL-6 and IL-1 receptor antagonist concentrations in major depression and treatment resistant depression. AB - There is now some evidence that major depression is accompanied by an immune response with an increased production of pro-inflammatory cytokines, such as interleukin 1(IL-1), IL-6 and interferon gamma (IFN-gamma). The aims of the present study were to examine serum IL-6, IL-1 receptor antagonist (IL-1Ra), IL 6R, Clara cell protein (CC16) and the soluble CD8 (sCD8) molecule in chronic, treatment resistant depression (TRD) both before and after subchronic treatment with antidepressants. Serum IL-6 and IL-1Ra were significantly higher in subjects with major depression and TRD than in normal controls. Subchronic treatment with antidepressants had no significant effects on serum IL-6, IL-1Ra, CC16 or sCD8, but reduced serum sIL-6R levels significantly. There were significant and positive correlations between serum IL-6, on the one hand, and sIL-6R, IL-1Ra, sCD8, number of peripheral blood leukocytes, neutrophils, CD2(+)T and CD19(+)B cells (all positive) and serum zinc (negative), on the other. These results suggest that: (1) major depression and TRD are accompanied by an activation of the monocytic arm of cell-mediated immunity; (2) the latter may be related to the immune an acute phase response in major depression; and (3) the above disorders may persist despite successful antidepressive treatment. PMID- 9367549 TI - ISS Assessment of the Influence of Nonpore Surface in the XPS Analysis of Oil Producing Reservoir Rocks AB - The application of X-ray photoelectron spectroscopy (XPS) to oil-producing reservoir rocks is new and has shown that pore surface concentrations can be related to rock wettability. In the preparation of fresh fractures of rocks, however, some nonpore surface corresponding to the connection regions in the rocks is created and exposed to XPS. To assess the potential influence of this nonpore surface in the XPS analysis of rocks here we use ion scattering spectroscopy (ISS), which has a resolution comparable to the size of the pores, higher than that of XPS, with an ion gun of He+ at maximum focus. Sample charging effects are partially eliminated with a flood gun of low energy electrons. All the ISS signals are identified by means of a formula which corrects any residual charging on the samples. Three rock samples are analyzed by XPS and ISS. The almost unchanged ISS spectra obtained at different points of a given sample suggest that the nonpore surface created in the fracture process is negligibly small, indicating that XPS data, from a larger surface spot, represents the composition of true pore surfaces. The significant changes observed in ISS spectra from different samples indicate that ISS is sample specific. Copyright 1997Academic Press PMID- 9367548 TI - Preparation and Organized Assembly of Nanoparticulate TiO2-Stearate Alternating Langmuir-Blodgett Films AB - Nanoparticulate TiO2-stearate Langmuir-Blodgett-type monolayers and multilayers were directly obtained by using TiO2 hydrosol as the subphase. The surface pressure-versus-surface area isotherms showed that the monolayer could be compressed to a mean molecular area of 0.25 nm2. The monolayer was transferred onto a CaF2 or Si substrate at a dipping speed of 18 cm/min and surface pressure of 25 mN/m. It exhibited Y-type multilayer films over the range investigated (1 30 layers) with a transfer ratio of 1.0 ± 0.1. FTIR transmission spectra and linear infrared dichroic spectra provided evidence of the formation of a stable organic/inorganic alternating multilayer with nanoparticulate TiO2 between the organic monolayers. There is only slight absorption in the range of the C;equals;O stretching vibration band of the carboxylic group with the 3- and 6-nm TiO2 nanoparticles. This means that TiO2 particles are packed closely; i.e., the surface coverage is very high. A possible structure consists of layers of nanoparticles in close-packed form with two stearate ion layers inbetween. But it can be seen that there are some carboxylic groups (1700 cm-1) not connected to the 20-nm TiO2 nanoparticle. Electron microscopic (TEM) images of TiO2-stearate monolayers show that high-coverage monolayers were obtained when the surface pressure increased to 25 mN/m and the dipping speed to 18 cm/min. Copyright 1997Academic Press PMID- 9367547 TI - Cytokine gene expression in liver following minor or major hepatectomy in rat. AB - Interleukin 6 (IL-6), tumour necrosis factor alpha (TNF-alpha), interleukin 1 (IL 1), and transforming growth factors alpha and beta (TGF-alpha and TGF-beta) are important mediators which play a pleiotropic role in both inflammatory and hepatic regeneration processes. It has also been proposed that a major hepatectomy impairs the liver-related host defence mechanisms. The aim of this study was to evaluate the influence of minor (30%) vs major (80%) hepatectomy on cytokines, growth factors and acute-phase proteins both at the protein and mRNA levels in rat. For that purpose, rats were submitted to either 30% or 80% hepatectomy and sacrificed at intervals up to day 14 post-hepatectomy to collect liver and blood samples. Serum levels of IL-6 and acute-phase proteins (APPs) were determined after RNA extraction, cytokine and acute-phase proteins gene expression were evaluated using a quantitative RT-PCR method. The results demonstrate that liver mRNA levels for IL-6 were early unregulated after a 80% resection only, whereas liver mRNA levels for IL-1 slowly increased following 30 or 80% hepatectomy. For TNF-alpha, no significant changes were observed between groups. Growth factor expression differed according to the extent of hepatic resection. Moreover, plasma levels of alpha2-macroglobulin (alpha2M) and alpha1 acid glycoprotein (AGP), two major APPs which respond differently to combination of cytokines, were significantly lowered after a major resection whereas levels of serum IL-6 showed no significant changes between groups. Paradoxically, in the 80% hepatectomized group, alpha2M mRNA expression was strongly increased at 4 h and 6 h post-hepatectomy as compared with the 30% hepatectomized group. Taken together, these results suggest that, although an increased level of hepatic IL-6 expression was observed following a major resection, the liver's capacity to synthesize normal levels of APPs was impaired. Moreover, these specific changes of cytokine gene expression seen in the liver following major hepatectomy might reflect a preferential activation of the IL-6-dependent APPs. PMID- 9367550 TI - Assembly Properties of a Glycoprotein Produced by Pseudoalteromonas antarctica, NF3 AB - The self-assembly properties of an extracellular material of glycoprotein character produced by a new Gram-negative species, NF3, Pseudoalteromonas antarctica, isolated from muddy soil samples of Antarctica have been investigated. The aggregation behavior of this exopolymer was studied directly by transmission electron microscopy (TEM) and analysis of digitalized TEM images of its aqueous dispersions before and after sonication. Increasing amounts of glycoprotein (GP) in water led to an abrupt decrease in the dispersion surface tensions up to a GP concentration of about 0.20 mg/ml (from 72 to 47 mN m-1), followed by an almost constant surface tension value. The size distribution curves of the aggregates formed always showed a bimodal distribution. The mean size of these two aggregates increased as GP concentration increased (first peak from 120 to 140 nm and second peak from 500 to 700 nm), reaching in both cases almost a constant value also for 0.20 mg of GP/ml of water. TEM images of unsonicated aqueous GP dispersions at concentrations lower and higher than 0.20 mg/ml always showed the coexistence of concentric multilamellar and small unilamellar aggregates, the small particles being the dominant class in the first case. Sonication of these dispersions revealed that each lamella of the initial multilamellar structures was made up of various subunits of coiled coil, whereas the smaller particles were not composed of these subunits. Profiles from digitalized TEM images of unsonicated and sonicated dispersions confirm that each lamella of large aggregates was composed of three subunits. Copyright 1997Academic Press PMID- 9367551 TI - Kinetics of Colloidal Deposition and Release of Polystyrene Latex Particles in the Presence of Adsorbed beta-Lactoglobulin Studied Using a Flow Cell AB - The effect of adsorbed whey protein, beta-lactoglobulin, has been investigated on the attachment of polystyrene latex particles to an indium tin oxide (ITO) surface and the subsequent release in anionic surfactant SDS solution and distilled-deionized water at pH 6.0. Experiments were carried out using a wall jet flow cell and particle attachment was measured in situ using the technique of evanescent wave microscopy. The deposition rate of particles increased as predicted up to a shear rate of approximately 1000 s-1, for deposition at a diffusion-limited rate. There was a reduction in the rate at higher shear rates indicating a decrease in sticking efficiency. As the shear rate increased, the ITO surface became saturated more quickly due predominantly to blocking of the surface by deposited particles. The presence of adsorbed beta-lactoglobulin on the ITO surface caused a large reduction in the subsequent deposition rate of protein-coated particles. This was due to an increase in electrostatic repulsion. Differences were found in both the extent of removal and in the release (cleaning) kinetics of particles in SDS and in distilled-deionized water for the different particle-protein-ITO surface conditions investigated. Release of particles was also independent of the shear rate. Results were interpreted by considering the roles of protein replacement and elution which occurs in SDS solutions; >90% removal of protein-coated particles from a coated ITO surface was observed in SDS when both processes play a role. This compared to 55% removal in distilled-deionized water where they were considered negligible. Copyright 1997Academic Press PMID- 9367552 TI - Detailed Analysis of Determination of Contact Angle Using Sphere Tensiometry AB - The configurations of the interfacial menisci around a sphere during the pulling process were analyzed and the methods for the simultaneous determination of surface and interfacial tension and contact angle were discussed. Furthermore, a method for the determination of contact angle using sphere tensiometry, which is independent of interfacial tension, was developed and tested with experiments. Copyright 1997Academic Press PMID- 9367553 TI - Transport Properties of Aqueous Glycerol and Aqueous Mannitol through the Zirconium Oxide Membrane AB - The transport properties of aqueous glycerol and aqueous mannitol across a zirconium oxide membrane are, investigated from the point of view of irreversible thermodynamics. The data on hydrodynamic permeability are analyzed in terms of frictional coefficients and entropy of activation. The phenomenological coefficient characterizing the electroosmotic flow and the membrane characteristics are also estimated for the various solutions with the object of determining the efficiencies of electrokinetic energy conversion and zeta potential. Copyright 1997Academic Press PMID- 9367554 TI - An Adhesion Map for the Contact of Elastic Spheres AB - Several continuum mechanics models of the adhesion between elastic spheres have found application to compliant materials such as rubber and to fine particles in the air or in colloidal suspension. More recently they are being used in connection with experimental techniques such as the surface force apparatus and the atomic force microscope. The appropriate model to use depends on the conditions: the size and elasticity of the spheres and the load to which they are subjected. To guide this choice a map has been constructed with nondimensional coordinates &mgr; and &Pmacr;, where the elasticity parameter &mgr; can be interpreted as the ratio of elastic deformation resulting from adhesion to the effective range of surface forces and the load parameter &Pmacr; is the ratio of the applied load to the adhesive force. A closed form solution to the problem based on a Dugdale force-separation law is outlined and used to construct the map. The errors introduced by the Dugdale approximation are assessed by comparison with numerical solutions using the Lennard-Jones force law. Copyright 1997Academic Press PMID- 9367555 TI - Stability of Dilute Colloidal Silica Suspensions in the Vicinity of the Binodal Curve of the System 2-Butoxyethanol/Water AB - In the temperature-composition diagram of the system 2-butoxyethanol (abbreviated C4E1)/water, SiO2 [mass fraction of SiO2, y(SiO2) approximately 0.01; volume fraction phi(SiO2) approximately 10(-3)] there exists a flocculation temperature composition curve running below the binodal curve for x > xc (x, mole fraction of C4E1; xc = 0.0598). The concentration of the colloidal particles is low enough to consider them an "impurity." In the region of the phase diagram bound by the binodal and the flocculation curve the suspension of the colloidal SiO2 particles is unstable and the particles flocculate reversibly. The difference between the temperature of phase separation and the flocculation temperature increases with increasing values of x - xc up to a maximum value of x (xmax). For x > xmax the suspensions are unstable at all temperatures studied. For x < xc the suspension of the SiO2 particles is stable up to the temperature of phase separation of the C4E1/water mixture. The flocculation curve is assumed to reflect the influence of local concentration fluctuations with long range correlations on the stability of the SiO2 suspensions. For x > xc these concentration fluctuations are water rich and interact with the hydrophilic surface of the colloidal SiO2 particles by forming an adsorption layer. This layer is assumed to modify the interparticle potential energy-distance curve and to trigger flocculation. For x < xc the concentration fluctuations are C4E1 rich and no adsorption layer is formed at the hydrophilic surface of the colloidal particles. Copyright 1997Academic Press PMID- 9367556 TI - Charge Regulation and Electrostatic Interactions for a Spherical Particle in a Cylindrical Pore AB - Previous theoretical analyses of electrostatic interactions for proteins in porous media have assumed that the protein (and pore) surface maintains either constant charge or constant potential during the interaction; however, the actual surface charge is determined by the extent of the surface ionization and binding reactions, both of which are altered when the protein enters the pore due to the change in the local ionic environment caused by the distortion of the electrical potential field. Theoretical calculations for the electrostatic potential are performed for a spherical particle in a cylindrical pore, accounting for this charge regulation phenomenon using a linearized form of the charge regulation boundary condition. The equilibrium partition coefficient in the pore is then evaluated from the free energy of interaction. Specific calculations are provided for the protein bovine serum albumin, with the charge regulation parameters evaluated from a model for the detailed protein charge characteristics. Model predictions are compared with experimental data for the bovine serum albumin sieving coefficient at different pH and ionic strength. These results provide important insights into the effects of charge regulation on the magnitude of the electrostatic interactions between charged proteins and charged pores. Copyright 1997Academic Press PMID- 9367557 TI - A Theoretical Study of Instabilities at the Advancing Front of Thermally Driven Coating Films AB - A thin liquid coating can spread vertically beyond the equilibrium meniscus position by the application of a temperature gradient to the adjacent substrate. So called super-meniscus films experience a surface shear stress which drives flow toward regions of higher surface tension located at the cooler end of the substrate. The Marangoni stresses responsible for this spreading process can also be used to coat horizontal surfaces rapidly and efficiently. Experiments in the literature have shown that in either geometry, the advancing front can develop a pronounced ridge with lateral undulations that develop into long slender rivulets. These rivulets, which prevent complete surface coverage, display a remarkable regularity in height, width, and spacing which suggests the presence of a hydrodynamic instability. We have performed a linear stability analysis of such thermally driven films to determine the most dangerous wavenumber. Our numerical solutions indicate the presence of an instability at the advancing front of films which develop a sufficiently thick capillary ridge. Our results for the film thickness profiles and spreading velocities, as well as the wavenumber corresponding to the most unstable mode, compare favorably with recent experimental measurements. An energy analysis of the perturbed flow reveals that the increased mobility in the thickened portions of the films strongly promotes unstable flow, in analogy with other coating processes using gravitational or centrifugal forces. Copyright 1997Academic Press PMID- 9367558 TI - Zeta Potential as a Tool to Characterize Plasma Oxidation of Carbon Fibers AB - Two different types of carbon fibers (ultrahigh modulus and high strength carbon fibers) were surface-treated in an oxygen plasma under equivalent conditions. Changes in the fiber surface chemistry were followed by electrokinetic measurements (zeta potential). The oxygen plasma treatment resulted in a displacement of the isoelectric point of carbon fibers toward lower pHs, evidence of an increase in the surface acidity. The possible simultaneous formation of basic functional groups was also inferred and supported by results obtained by inverse gas chromatography and wettability measurements. Differences were more evident with ultrahigh modulus carbon fibers than with high strength carbon fibers. It is concluded that the measurement of the electrokinetic properties constitutes a useful technique to follow the evolution of the surface chemical characteristics of different types of carbon fibers. Copyright 1997Academic Press PMID- 9367559 TI - Stability of Nonaqueous Emulsions AB - We examined the stability of emulsions of oil in several nonaqueous polar liquids using commercially available nonionic surfactants. Stable nonaqueous emulsions were only obtained with formamide and dimethylsulfoxide. Hydrogen bonding, and not polarity, appears to be the important factor determining the emulsifying power of a solvent. Ostwald ripening plays a much more important role in the stability of these nonaqueous emulsions than in the corresponding aqueous systems. This destabilizing process can be prevented, however, by addition to the oil phase of a small amount (1%) of an oil that has a very low solubility in the continuous phase. Furthermore, a larger size of the surfactant molecule protects emulsions against droplet coalescence. Thus, emulsions in formamide and dimethylsulfoxide did not show any breakdown when stabilized with a triblock copolymer of polyoxyethylene-polyoxypropylene-polyoxyethylene. Copyright 1997Academic Press PMID- 9367560 TI - The Electric Conductivity of Dilute Suspensions of Charged Porous Spheres AB - The effective electric conductivity of a dilute suspension of polyelectrolyte molecules or charged flocs in an electrolyte solution is analytically studied. The model used for the particles is a porous sphere in which the density of hydrodynamic frictional segments, and therefore also that of the fixed charges, is constant. The equations which govern the electrochemical potential distributions of ionic species and the fluid flow field inside and outside a porous particle migrating in an unbounded solution are linearized assuming that the system is only slightly distorted from equilibrium. Using a perturbation method, these linearized equations are solved for a porous sphere in a uniform applied electric field with the density of the fixed charges as the small perturbation parameter. An analytical expression for the effective conductivity of a dilute suspension of identical charged porous spheres is obtained from the average electric current density calculated using the solution of electrochemical potential distributions of the ions. The result demonstrates that the presence of the fixed charges in the porous particles can lead to an augmented or a diminished electric conductivity of the suspension relative to that of a corresponding suspension of uncharged porous particles, depending on the characteristics of the electrolyte solution and the suspending particles. When the anionic and cationic diffusion coefficients of a symmetric electrolyte are the same, the correction for the effect of the fixed charges of the particles on the electric conductivity of the suspension is proportional to the square of the fixed charge density. Copyright 1997Academic Press PMID- 9367561 TI - Effects of Particle Surface Conditions on Conductivity of Spherical Dispersions AB - The effect of particle surface conditions on the effective conductivity of spherical dispersions is investigated. The spherical particles can be either coated with multiple layers or possessive of a certain amount of contact resistance, and can be either randomly distributed or arranged in simple cubic arrays. The effective conductivity of the dispersion is found to be a function of the particle volume fraction and the dimensionless multipole polarizability. Expressions for the dimensionless multipole polarizability for both multiply coated sphere and contact resistance problems are derived. The effect of particle surface conditions is realized through their influence on the magnitude of the multipole polarizability, and the effect of the multipole polarizability on the effective conductivity is carefully examined. It is further found that, for random arrays, all members of the multipole polarizability are involved in the evaluation of the effective conductivity, but only half of them are involved for simple cubic arrays. In addition, the contact resistance problem has a narrower polarizability variation range than that of the multiply coated sphere problem. These two factors profoundly contribute to the differing effect of multipole polarizabilities on the effective conductivity of the dispersion with respect to the dispersion microstructure and particle surface conditions. Copyright 1997Academic Press PMID- 9367562 TI - Adsorption of Dibenzothiophene on Marine Sediments Treated by a Sequential Procedure AB - The sorption behavior of dibenzothiophene on marine sediments treated by a sequential procedure was investigated. Sorption isotherms for dibenzothiophene on both no treatment and NaOAc-HOAc treatment sediments were all linear. Differences in Kp's between no-treatment and NaOAc-HOAc treatment sediments were mainly the result of differences in organic carbon content. Nonlinear adsorption isotherms of dibenzothiophene were observed on the sediments treated with H2O2 and could be described by the Freundlich equation. Nonlinear isotherms suggested that the sorption mechanism was a heterogenous adsorption process occurring on the surfaces of the residual organic matter and the bare inorganic minerals in the sediment. A linear correlation was found between the Freundlich constant K and the residual organic carbon. In addition, the clay content in the sediment also had a significant effect on the residual organic carbon content and the Freundlich constant K. Differences in the isotherms of dibenzothiophene between the H2O2 treatment sediments and the no or NaOAc-HOAc treatment sediments indicated that the sorption was strongly influenced by the change in composition as well as by the percentage of organic matter in the sediments. Copyright 1997Academic Press PMID- 9367563 TI - Properties of Decylammonium Chloride and Cesium Perfluorooctanoate at Interfaces and Standard Free Energy of Their Adsorption AB - Measurements of the surface tension of aqueous solutions of decylammonium chloride (DACl) and cesium perfluorooctanoate (CsPFO) and the interfacial tension of DACl (CsPFO) solution-decane and DACl (CsPFO) solution-benzene systems were made at 293 and 303 K. On the basis of these measurements, the adsorption isotherms and the standard free energies of adsorption were determined. Also, the standard free energy of adsorption was determined from the surface free energy of the tails of DACl and CsPFO and the interfacial free energy of the tail-water system. It was found that the standard free energy of adsorption at a given temperature only slightly depends on the type of phase in contact with the solutions of the surfactants and can be determined on the basis of the surface and interfacial free energy of systems including the tails of the surfactants. It was also found that standard free energy of adsorption depends on temperature, and is considerably smaller for CsPFO than for DACl. Copyright 1997Academic Press PMID- 9367564 TI - Statistical Effects of the Binding of Ionic Surfactant to Protein AB - Two different theories based on a multiple equilibrium model for analysing the binding data for ionic surfactant-protein interactions are investigated and modified, and intrinsic and statistical Gibbs free energies of binding per mole of surfactant are estimated. The characterization of the two models and interpretation of the binding process in terms of intrinsic and statistical binding free energies are discussed. These theories are applied to analysis of sodium n-dodecyl sulfate binding to ribonuclease A and lysozyme. Copyright 1997Academic Press PMID- 9367565 TI - Liesegang Ring Type Structures and Bifurcation in Solid-Vapor and Liquid Phase Reactions between Cobalt Nitrate and Ammonium Hydroxide AB - New results on the reaction between (i) cobalt nitrate (A) and ammonium hydroxide (B) in gelatin and (ii) cobalt nitrate (solid) and ammonia vapor are reported. Spatial bifurcation of the blue wave into a number of normal Liesegang type bands is observed in a one-dimensional tube in gel media depending on the concentration of electrolytes and gel. Similar bifurcation is also observed when the reaction was carried out in gel media between two microslides. Results show that Ksp (solubility product), as envisaged in recent theories, plays a significant role in initiating bifurcation depending on K, the magnitude of the product of concentration of A and B, which determines the degree of supersaturation. The value of K at the instant of bifurcation, when (i) concentration of Co(NO3)2 is alone changed or when (ii) concentration of NH4OH alone is changed, is similar when uncertainties are taken into account. The bifurcation behavior when gel concentration is changed suggests that in case of high gel concentration pore size is affected, thereby influencing the diffusion of ions. The results satisfy the spacing law. The results further satisfy the relation d2 = m't + C' at any time t, where d is the distance between the lower front of the precipitate and the junction and m' and C' are constants, thereby suggesting that the role of diffusion is vital, as envisaged in various theories of the phenomenon. A colored banded structure separated by air gaps (vacant spaces) is formed when the solid cobalt nitrate reacts with ammonia vapor. This type of behavior has not been reported earlier. Initially, a single band is formed in a one-dimensional experiment, but in the course of time ( approximately 1 month) several bands are formed simultaneously. The diffusion kinetics in the initial stages of the solid vapor reaction has been studied in a one-dimensional tube. The data obey the relation xi2 = kt, where xi is the thickness of the product layer at any time t and k is some constant. Similar studies were made on microslides which showed that during the reaction, a colored product is formed which undergoes change in the sequence pink --> blue --> brown. Results in the one-dimensional case support recent theories which postulate nucleation followed by aggregation. Copyright 1997Academic Press PMID- 9367566 TI - Stabilization of Liposomes Attached to Polymer Surfaces Having Phosphorylcholine Groups AB - The adsorption state of liposomes on a polymer surface containing a phosphorylcholine group, that is, omega-methacryloyloxyalkyl phosphorylcholine (MAPC) polymer, was evaluated using a quartz crystal microbalance and an atomic force microscope. After a quartz crystal resonator coated with the MAPC polymer or poly[2-hydroxyethyl methacrylate (HEMA)] was equilibrated with distilled water, the quartz crystal was contacted with a dipalmitoylphosphatidylcholine (DPPC) liposomal suspension. The resonance frequency change during liposome adsorption on the poly(HEMA)-coated resonator was larger than that on the MAPC polymer-coated resonator. The temperature response based on the phase transition of adsorbed DPPC liposomes, that is, the liquid crystalline state to gel state, on the MAPC polymer-coated resonator was more sensitive than that on the poly(HEMA)-coated resonator. Moreover, when the DPPC liposomes adsorbed on the polymer surfaces were disintegrated with a nonionic surfactant, it took longer for the frequency to return to the initial value of the poly(HEMA)-coated resonator than to that of the MAPC polymer-coated resonator. According to atomic force microscopic observation of the polymer surface after treatment with the liposomal suspension, the DPPC liposomes adsorbed on the MAPC polymers maintained their spherical shape well. We conclude that DPPC liposomes adsorbed on the poly(HEMA) surface can penetrate a hydrated layer and its ordered structure. On the other hand, DPPC liposomes may adsorb to the MAPC polymer surface without change in their original structure. Copyright 1997Academic Press PMID- 9367567 TI - Study of Ni-Impregnated Active Carbon AB - The reduction of NO with CO on Ni-impregnated active carbon catalysts (AC/Ni) has been investigated. High activity toward NO reduction can be achieved on an AC/Ni catalyst obtained by thermal decomposition of the precursor nitrate at 200°C. The role of active carbon in the catalytic reduction of NO with CO at different temperatures has been discussed. At low temperatures (below 200°C), when there is no substantial gasification of the carbon, dissociative adsorption of NO along with N2 evolution and oxygen accumulation on the carbon surface has been observed. The active sites occupied by the oxygen evolved during the NO decomposition are regenerated by the CO reducing agent. At high temperatures the C-O complexes evolved from the carbon surface participate in NO reduction as a second reducing agent. The effect of the oxygen-containing functional groups and the available nitrate groups on catalyst activity has been discussed. Copyright 1997Academic Press PMID- 9367568 TI - Effect of N-Sulfonation on the Colloidal and Liquid Crystal Behavior of Chitin Crystallites AB - Chitin crystallites were heterogeneously N-sulfonated in an aqueous medium using triethylamine/sulfur trioxide (TEA/SO3) or pyridine/sulfur trioxide. The extent of N-sulfonation of the crystallites has been controlled by the amount of TEA/SO3 added in the reaction. The concentration of sulfur in the crystallites after N sulfonation was quantified using conductimetric titration and elemental analysis. The ratio of N-sulfonated amino groups to amino groups (S/N) was calculated based on the titration data. The presence of N-S bonds assumed to be at crystallite surfaces was demonstrated by X-ray photoelectron spectroscopy (XPS). After N sulfonation, the crystallites have two ionizable groups at their surface: -NH3+ and -NHSO3H(Na). The former is pH dependent. The colloidal properties of the N sulfonated crystallites having different S/N were investigated by plotting the zeta potential as a function of the pH of the suspension. The isoelectric point was found to change with the level of N-sulfonation. Transmission electron microscopy shows that the aggregation of crystallites depends strongly on the extent of N-sulfonation. Above a certain concentration, the original chitin crystallites form tactoids (chiral nematic domains) in an aqueous medium. This phenomenon was not observed for the crystallites with a low extent of surface N sulfonation (below 70%). At about 80% N-sulfonation, the formation of tactoids was once again observed. Copyright 1997Academic Press PMID- 9367569 TI - Effect of Inorganic Additives on Solutions of Nonionic Surfactants AB - The salt effects of 10 transition metal cations on nonionic surfactants were investigated by the action of their salts (nine nitrates, two sulfates) on the cloud point (CP) of octoxynol 9. All cations investigated raised the CP of octoxynol 9 by complexation with its ether groups, which represents salting in. However, aside from Ag+, these CP increases were no larger than those caused by Li+ and by di- and trivalent cations not belonging to the transition metal group, even though the transition metal cations have a greater capacity for forming complexes. This unremarkable, average salting-in capacity of most transition metal cations is attributed to competition for their coordination sites between the ether groups of the surfactant and water. With the exception of silver, the solid nitrates of all transition metals examined form stable solid hydrates containing three to nine molecules of water of crystallization, which indicates a high affinity of the cations for water. Only AgNO3 forms no stable solid hydrates. The low affinity of Ag+ for water results in a commensurately higher capacity for binding the ether groups of the surfactant. This was shown by the facts that AgNO3 produced the largest CP increases and that it was the only salt to reversibly precipitate an insoluble adduct with octoxynol 9 from concentrated solutions. The only salt that oxidized the surfactant when its solution was heated in a nitrogen atmosphere and illuminated during CP measurements was Fe(NO3)3. Oxidative degradation produced small but progressive CP reductions. Copyright 1997Academic Press PMID- 9367570 TI - Measurement of Absolute Coagulation Rate Constants for Colloidal Particles: Comparison of Single and Multiparticle Light Scattering Techniques AB - The absolute coagulation rate constants of monodisperse spherical colloids in aqueous suspension were measured at the early stage of the coagulation processes by using two different techniques: single particle light scattering (SPLS) and simultaneous static and dynamic light scattering (SLS + DLS). Single particle light scattering determines the cluster-size distribution directly by counting the number of different clusters during the coagulation process and therefore can be used to test the kinetic growth model used for obtaining the coagulation rate constants. The simultaneous static and dynamic light-scattering method is an in situ experiment, where the average cluster size is estimated by simultaneous static and dynamic light-scattering measurements at different angles on a multiangle fiber-optics-based setup. A combined evaluation of the static and dynamic light-scattering data permits the determination of the absolute rate constants without the explicit use of light scattering form factors and hydrodynamic properties for dimers. In this paper, we compare results obtained with both techniques. Good agreement was found for the absolute coagulation rate constants of two different latex particle suspensions. Furthermore, we show that the two techniques complement one another and the limitations of the first are overcome by the second and vice versa. Copyright 1997Academic Press PMID- 9367571 TI - A Nonelectrical Mechanism of Ion Exclusion in Thin Water Films in Finely Dispersed Media AB - Usually, ion exclusion in fine porous media is explained by the effect of the double electrical layer caused by the surface charge of particles. This paper shows the possibility of another, nonelectrical mechanism of ion exclusion which may act in parallel. Nonelectrical ion exclusion is induced by high negative specific pressures existing in thin water films. Existing data on these pressures in soil are analyzed. Theoretical calculations performed for some common natural soil salts have shown that the equilibrium constant for the precipitation dissolution reaction decreases drastically when the capillary pressure becomes lower than minus 1.5-10 MPa. Thus, the saturation state has to develop at considerably lower ion concentrations. Calculations reveal that for air-dry soil (capillary pressure about 100 MPa), the equilibrium constants in hygroscopic water have to be equal to 0.02-58% of their values for free or capillary water in wet soil. Ion concentrations also have to be diminished in the first water layers of wet soil as compared with the next layers. The Ca2+, Mg2+, SO42- and HCO3- deficiency in hygroscopic water has to be especially noticeable. For anions, such nonelectrical ion exclusion is enhanced by the row Cl- < HCO3- < SO42-, which corresponds to the same trend as is predicted by the theory of the double electrical layer. Obtained results provide an explanation of the existence of the conventional "nonsolvent volume of soil water" experimentally determined in the past for anions, cations, and electrically neutral substances. Copyright 1997Academic Press PMID- 9367572 TI - Preparation and Characterization of Active Carbon Adsorbents for Wastewater Treatment from Elutrilithe AB - Active carbon adsorbents were prepared from natural elutrilithe by chemical activation with K2CO3. The effect of pyrolysis temperature and time and K2CO3/elutrilithe ratio on the surface area, porosity, and ash content of the adsorbents was studied. Various prior and post treatments have been tried to improve the quality of the adsorbents. An ideal active carbon adsorbent with a BET surface area of 1236 m2/g and a total pore volume of 0.679 cm3/g has been obtained. The adsorbent is hydrophobic in nature and exhibits large adsorption capacities for various phenolic compounds from aqueous solutions. Copyright 1997Academic Press PMID- 9367573 TI - Electrostatic Potential Distribution for Spheroidal Surfaces in Symmetric Electrolyte Solutions AB - The electrostatic potential distribution for a charged spheroidal surface immersed in a symmetric electrolyte solution is derived. Such surfaces simulate a wide class of dispersed entities. Two types of boundary condition at the solid surface are considered, constant surface potential and constant amount of surface charges; both conductive and nonconductive surfaces are examined for the latter. The present analysis extends the conventional one-dimensional treatment on simple geometries to a two-dimensional space. A perturbation method is adopted to solve the governing Poisson-Boltzmann equation for the case of thin to moderately thick double layers. The classic results for planar and spherical surfaces can be recovered as special cases of the present analysis. The basic thermodynamic properties of the system under consideration, such as Helmholtz free energy, entropy, and surface excess, are derived. We show that using an equivalent sphere to approximate a spheroid can lead to an appreciable deviation in the prediction of the Helmholtz free energy. For a thin double layer, assuming a planar geometry will underestimate the Helmholtz free energy. Copyright 1997Academic Press PMID- 9367574 TI - Kinetic Analyses of the Colloidal Crystallization of Silica Spheres As Studied by Reflection Spectroscopy AB - Reflection spectroscopy is used in kinetic analyses of the nucleation and growth processes of colloidal crystals of silica spheres (110 nm in diameter) in exhaustively deionized aqueous suspensions. Sphere concentrations range from 0.001 to 0.0025 in volume fraction (phi) for the nucleation and 0.0014 to 0.0036 for the crystallization process, respectively. Induction periods are from 1 to 500 s and become longer with decreasing sphere concentration. Nucleation rates are 10(-3) to 10(3) &mgr;m-3 s-1 and increase sharply as sphere concentration increases. The crystallization process has been observed through the sharpening and the increase of intensity in the reflection peaks for the suspension in a test tube, which stands still after being inverted. Crystal growth rates v range from 2 to 15 &mgr;m/s and decrease linearly as the reciprocal sphere concentration increases. Crystal growth rates represented by the number of unit cells u also increase as phi increases, ranging from 2 to 23 unit cells/s. The importance of electrostatic intersphere repulsion through electrical double layers and of cooperative fluctuation of colloidal spheres in crystallization processes is supported. Copyright 1997Academic Press PMID- 9367575 TI - Condensation of Droplets on Ions and the Generalized Kelvin Equation for an Electrolyte Solution AB - A thermodynamic description of condensation of droplets on ions is presented. The Gibbs free energy of noninteracting droplets in equilibrium with their vapor is a function of the number of moles, temperature, pressure, and surface tension G (p(r), T, sigma, n1g, ellipsis, ncg; n1l, ellipsis, ncl; ncl; n1sigma, ellipsis, ncsigma). From the variation around equilibrium of G, an equation relating saturation pressure and droplet size is obtained. The saturation ratio is considerably reduced by adding an ionic salt (the solute). Ion hydration allows the formation of stable droplets in an unsaturated environment. Their effect prevails at small values of the droplet radius r where the equation exhibits a stable branch and predicts condensation, even in the case of a perfect ionic solution. The equation also shows that an ionic mixture behaves as a pure solvent (metastable branch, Kelvin limit) for large r. We compare our results with those previously obtained. Copyright 1997Academic Press PMID- 9367576 TI - Model for Interpretation and Correlation of Contact Angle Measurements AB - An improved formulation relating the contact angle to the surface coverage is presented and verified. The Ohmi et al. data (Particle Sci. Technol. 7, 229, 1993) for ultracleaning of wafer surfaces are analyzed and correlated mathematically. It is shown that the new formulation represents the Ohmi et al. and Englander et al. (J. Colloid Interface Sci. 179, 635, 1996) data satisfactorily. In addition, the present study provides some insight into the mechanism of the variation of the surface coverage and the contact angle. Copyright 1997Academic Press PMID- 9367577 TI - Integral Eqution Approach for Solving the Nonlinear Poisson-Boltzmann Equation AB - A simple iterative method is devised for solving the nonlinear Poisson-Boltzmann equation. The method is based on the integral representation of the Poisson Boltzmann equation and can be readily implemented for determining the potential and charge density around particles of various shapes. As an illustrative example the method is applied for computing the potential and surface charge density of the spherical double layer. Copyright 1997Academic Press PMID- 9367578 TI - Sorption of Metal Ions on Alumina AB - Precipitation and adsorption of metal ions (Co(II), Ni(II), Cu(II), and Cr(III)) on gamma-alumina were investigated experimentally. A surface chemical reaction model to calculate concentrations of aluminum ions, metal ions, and pH as variables depending on amount of alumina, volume of liquid and gas phase, initial metal concentration, and amount of acid or base added is presented. In the case of Co(II) the pH dependence of rest concentrations with and without alumina is equal; adsorption may be disregarded. For the other ions adsorption is important. Considering the charge of the surface does not improve the fit. In the pH region, where adsorption leads to lower rest concentrations than precipitation, adsorption may be described by a Henry isotherm. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367579 TI - Adsorption of Thorium on Amorphous Silica: An EXAFS Study AB - Wet samples of Th(IV) sorbed on colloidal amorphous silica particles (Aerosil OX 200) have been studied with extended X-ray absorption fine structure spectroscopy (EXAFS) at the Th LIII edge (16.3 keV). The samples were collected with sample surface coverages ranging from 3.8 to 230%. No fundamental changes in the structural environment of Th in terms of the types and distances of nearest neighbors with increasing surface loading were detected, but the results indicate an increasing degree of structural disorder with increasing surface coverage. The O shell around Th shows a distorted configuration with two O atoms at 2.33 A distance and four to six O atoms at 2.55 A. Only one Si shell is observed, with two Si atoms at a distance of 3.8-3.9 A. These results have been interpreted with a double corner-sharing surface complex of Th on silica, where the Th atom shares one O atom with each of two coordinated SiO4 tetrahedra, accounting for the first O coordination shell detected as well as the Th-Si distances. The longer Th-O distances result from coordinated water molecules from solution. No Th-Th interactions could be detected in the EXAFS spectra. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367580 TI - Surface Tension and Viscoelasticity of Alkane Solubilized Surfactant Monolayers AB - The behavior of solubilized alkanes at the surface of DoTAB solutions for various surfactant bulk concentrations below and above the cmc is described. Several techniques such as tensiometry, ellipsometry, and Brewster angle microscopy, as well as an excited capillary wave device are used for the study. Alkanes do not wet the surface completely and form a mixed monolayer with the surfactant. Rather unusual viscoelastic behavior is observed for the mixed monolayers. This suggests a new type of relaxation phenomenon, but its origin remains to be elucidated. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367581 TI - Interbubble Gas Diffusion and the Stability of Foams AB - Foam decay may arise from liquid drainage, whether gravitational, due to interbubble gas diffusion, or from rupture of the interbubble liquid lamellae. In our study of factors affecting foam stability, we focus on interbubble gas diffusion, which works against stability even given a stable lamella. We show that liquid drainage from the foam due to such diffusion (as distinct from that due to gravitation) can often be greatly reduced by adding a water-insoluble vapor to the foam-generating gas: the presence of such a vapor counterbalances the Ostwald ripening, thus stabilizing the system. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367582 TI - Surface and Spectroscopic Properties of Acetylcholinesterase Monolayer at the Air/Water Interface AB - The behavior of the enzyme acetylcholinesterase was studied at the air/water interface. Surface pressure-area (pi-A) isotherms and UV-vis spectra recorded at different surface pressures were determined for different salt concentrations in the subphase. The ionic strength of the subphase does not influence the physical properties in consideration; however, the pH of the subphase has a great effect on its surface and optical properties. A subphase at pH 6.5 has shown that the enzyme is highly stable, based on the pi-A compression/decompression isotherms. No changes in the area per molecule were observed when the surface pressure was maintained constant at 16 mN/m for a period of 120 min. The long-term stability of acetylcholinesterase at the air/water interface was demonstrated for pH 6.5 and a salt concentration of 10(-2) M (KCl). The absorption spectra of the monolayer, measured directly at the air/water interface, are considered good evidence of the organization of the enzyme molecules. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367583 TI - Influence of Particle Orientation on One-Dimensional Compression of Montmorillonite AB - Methods have recently been developed for calculating the double-layer repulsive and the van der Waals attractive forces between two nonparallel clay particles immersed in a fluid system. In the present study, these theories are used in an approximate model of one-dimensional compression to examine the role of particle orientation on the behavior of a montmorillonite. It is shown that consideration of nonparallel fabric could potentially explain the discrepancy observed in the past between experimental and theoretical behaviors. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367584 TI - Incorporation and Antibody Recognition of a Lipid-Anchored Membrane Protein in Supported Lipid Layers AB - The formation of supported lipid layers incorporating promastigote surface protease (PSP), a glycosylphosphatidylinositol-anchored protein, is investigated using surface plasmon resonance. Both hydrophilic and hydrophobic substrates are used for the formation of lipid layers, and results are consistent with the formation of lipid bilayers and monolayers, respectively. Specific antibody binding to layers containing PSP is observed, whereas nonspecific binding of the antibody to the surface is effectively suppressed by the phosphatidylcholine lipid layer. Phosphatidylinositol-specific phospholipase C is used to remove the lipid moieties from the membrane-incorporated PSP, releasing it into solution in a hydrophilic form and demonstrating that a large fraction of the protein is anchored in the lipid layer via the lipid moieties. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367585 TI - Adsorption of Pb(II), NTA, and Pb(II)-NTA onto TiO2 AB - Nitrilotriacetic acid (NTA) is extensively used in different industries because of its excellent chelating properties. Introduction of NTA into the natural environment is a concern because of mobilization of heavy metal species that may be otherwise bound to natural particulate matter. The present study investigates the adsorption behavior of Pb(II) and NTA, both as individual species and as complex species onto titanium dioxide. This adsorption information is important in considering the TiO2-assisted photocatalytic treatment of these metal-organic complexes. Pb(II) shows a typical cationic type of adsorption behavior, whereas NTA demonstrates an anionic type of adsorption trend. Results from stoichiometric ternary systems show a gradual increase in Pb(II) adsorption and a decrease in NTA removal with an increase in pH. However, for the cases of Pb(II) > NTA, increased NTA adsorption as compared to pure NTA systems was noted even at higher pH. Model predictions employing MINTEQA2 software followed the experimental trends. Experimental and model results from ternary systems suggest adsorption of free Pb(II) and NTA, as well as ternary Ti-NTA-Pb(II) and Ti-O-Pb(II)-NTA2- species. The cationic-type complexation, i.e., Ti-O-Pb(II)-NTA2-, was essential for the successful NTA adsorption modeling, especially at higher pH and for Pb > NTA systems, where significant NTA adsorption was noted even at very high pH values. Most of the previous metal-ligand adsorption studies did not consider such a surface complexation. However, the present results indicate that any groundwater transport modeling of such pollutants will require the inclusion of cationic-type surface complexation, in addition to other surface species. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367586 TI - Monte Carlo Study of Chemically Associating Polymerizing Two-Dimensional Fluids AB - NVT Monte Carlo simulations are reported for chemically associating two dimensional fluids which can polymerize for certain interaction energies, due to the presence of two attractive sites per monomeric hard disc. The sites are fixed inside a hard core at a given valence angle and mutual penetration of discs is permitted. The type of products of polymerization depends on the parameters of the model; we observe the formation of small associates, as well as of extended chains, bent chains, and rings with different number of monomers. The values of valence angles and of association energy are of primary importance. The dependence of the structural properties of the model on fluid density and association energy is investigated. We performed detailed analysis of the clusters formed due to association in terms of fractions of singly and doubly bonded particles, of average numbers of chains and rings, and of their size. We also obtain the average end to end distance, the radius of gyration, and the persistent length of the products of polymerization. The pressure is calculated from the density profiles of particles of the polymerizing fluid near a hard "wall." The data can be used to develop the equation of state for chemically associating two-dimensional fluids. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367587 TI - Assessing Extreme Models of the Stober Synthesis Using Transients under a Range of Initial Composition AB - 29Si-NMR, conductimetry, and photon correlation spectroscopy are used to monitor the temporal profile of intermediate concentrations in Stober synthesis (i.e., ammonia-catalyzed hydrolysis of tetraethoxysilane in a batch reactor). Extreme models of the process are assessed by examining the effect of initial composition on these transients (over a wider range of composition than attempted previously). The trends with initial composition suggest that the nucleation is rate-limited by the hydrolysis of the singly hydrolyzed monomer, the product of which probably phase separates. Moreover, the trends are consistent with the aggregation model discussed by G. H. Bogush and C. F. Zukoski (J. Colloid Interface Sci. 142, 1, 19 (1991) and by M. T. Harris (Ph.D. dissertation, Univ. of Tennessee, 1992). The trends are not consistent with a growth model without aggregation. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367588 TI - Molecular Transport and SAPO-11 Crystal Growth in an i-Pr2NH-AlPO4-H3PO4-SiO2-H2O System AB - The crystal growth of SAPO-11 molecular sieve synthesized with i-Pr2NH as a novel template from mixtures of Si, Al, and P sources were studied by XRD, MAS-NMR, IR, and AAS techniques. It was found that the crystallization was improved partially by the desorption of i-Pr2NH from the crystallite products at high temperatures. The growth on (010) face was enhanced by stepwise adding external silica sol to the reaction mixtures during the synthesis process. The molecular transport and mechanism of the crystallization were discussed. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367589 TI - Electrokinetic Effects on Pressure-Driven Liquid Flows in Rectangular Microchannels AB - The effects of the electrical double layer near the solid-liquid interface and the induced electrokinetic field on the pressure-driven liquid flow through a rectangular microchannel are analyzed in this work. A nonlinear, two-dimensional Poisson-Boltzmann equation governing the electrical double layer field in the cross section of rectangular channels is numerically solved with the use of a finite-difference scheme. A body force caused by the electrical double field and the flow-induced electrokinetic field is considered in the equation of motion. An exact solution to this equation of motion in rectangular microchannels is obtained by employing the Green function formulation. The effects of the ionic concentration of the liquid, the zeta potential of the solid surface, and the size and the shape of microchannels on the fluid velocity distribution, streaming potential, volumetric flow rate, friction coefficient, and apparent viscosity are discussed. The results clearly show that for a liquid solution of low ionic concentration and a solid surface of high zeta potential the liquid flow in rectangular microchannels is significantly influenced by the presence of the electrical double layer field and hence deviates from the flow characteristics described by classical fluid mechanics. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367590 TI - Additive Effects on the Microstructure Evolution in Hexadecyltrimethylammonium Bromide Solution and Its Rheological Properties AB - The effects of various additives on the microstructure evolution in hexadecyltrimethylammonium bromide micellar solution and its rheological properties are investigated. The additives considered in the present study are primary, secondary, and tertiary heptanols and sodium salicylate (NaSal). The microstructure is developed via the two-step shape transitions in the micellar solution; first, the initial spherical micelles undergo shape transition to rod like or disc-like micelles as the micelles tend to be packed compactly with increase in the surfactant concentration; then further increment in the surfactant concentration makes the anisotropic rod-like micelles overlap each other. Solutions in these states exhibit typical non-Newtonian behaviors such as shear thinning at high shear rates. In the present study, the additive effects on the microstructure evolution are investigated by employing various techniques including a phase modulated flow birefringence, a dynamic light scattering and a dynamic oscillatory rheometry. The results show that addition of the solubilized additives enhances the microstructure transitions, which are affected by the additive concentration and its chemical structure. Presence of the cosurfactants such as heptanols with hydrophobic alkyl chains reduces the repulsion by forming surfactant-alcohol mixed micelles. The primary heptanol can penetrate easily into the micelles and aligned parallel to the surfactant molecules compared with the secondary and tertiary heptanols. Thus, the primary heptanol enhances the two step shape evolutions more effectively than the other types. In the presence of NaSal, on the other hand, the micellar solution exhibits the viscoelastic properties and the yield stress owing to the formation of networked or worm-like micelles. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367591 TI - Solubilization of Gases by Polyethoxylated Octyl Phenols AB - Measurements have been made to determine the solubilities of a number of gases in aqueous solutions of commercially available polyethoxylated octyl phenols at temperatures ranging from 25°C to 45°C (298-318 K). The solubilities determined for each gas increase linearly with surfactant concentration. The intramicellar gas solubilities derived from these data are found to be relatively insensitive to temperature and sodium chloride in the external aqueous phase. When analyzed in terms of surfactant composition, the intramicellar gas solubilities are found to depend solely on the octyl phenol content of each surfactant. This suggests that the ethylene oxide chains of the micellized surfactant molecules do not contribute directly to the solubilization process, even under conditions near the cloud point. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367592 TI - Elution Behavior of Chemically Different Probes on the Evaluation of Surface Properties of Cellulose by Inverse Gas Chromatography AB - The inverse gas chromatography (IGC) technique has been employed to examine adsorption behavior of cellulose surfaces from elution characteristics of chemically different adsorbates. The neutral probes were eluted completely during IGC measurements while acidic, amphoteric, and basic probe molecules were eluted incompletely. In this work, complete elution is defined by the flat postpeak FID signal within the noise limits of the detector. An understanding of incomplete elution is thereby reached by introducing a precisely controlled, very small quantity of individual probes into the column. A strong correlation is found between elution efficiency of vapors and their enthalpies of acid-base interactions. Delayed elution of acid-base vapors is interpreted as being due to nonequilibrium sorption process, and calculations have shown that diffusion into the bulk is unlikely under the measurement conditions. The chromatographic process is simulated and it is found that the contribution of nonequilibrium adsorption to the retention is responsible for observed peak tailing and thereby delayed elution of acid-base probes. Results of the study indicate that characterization of acid-base (electron acceptor-donor) type of stationary phase material surfaces by IGC needs careful attention and is an area for future work. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367593 TI - 2-D and 3-D Interactions in Random Sequential Adsorption of Charged Particles AB - We explore the influence of electrolyte concentration on the adsorption of charged spheres using modeling techniques based on random sequential adsorption (RSA). We present a parametric study of the effects of double layer interactions between the charged particles and between the particle and the substrate on the jamming limit using a two-dimensional RSA simulation similar to that of Z. Adamczyk et al. (1990, J. Colloid Interface Sci. 140, 123) along with a simple method of estimating jamming limit coverages. In addition, we present a more realistic RSA algorithm that includes explicit energetic interaction in three dimensions, that is, particle-particle and particle-surface interactions during the approach of a particle to the substrate. The calculation of interaction energies in the 3-D RSA model is achieved with the aid of a three-body superposition approximation. The 3-D RSA model differs from the 2-D model in that the extent of coverage is controlled by kinetic rather than energetic considerations. Results of both models capture the experimentally observed trend of increased surface coverage with increased electrolyte concentration, and both models require the value of a key model parameter to be specified for a quantitative match to experimental data. However, the 3-D model more effectively captures the governing physics, and the parameter in this case takes on more meaningful values than for the 2-D model. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367595 TI - Effect of Solvent Quality on Reverse Micelle Formation and Water Solubilization by Poly(ethylene oxide)/Poly(propylene oxide) and Poly(ethylene oxide)/Poly(butylene oxide) Block Copolymers in Xylene AB - In addition to associating into ("normal") micelles in aqueous solutions, amphiphilic polyoxyalkylene block copolymers can form "reverse" micelles in organic solvents at sufficiently high copolymer concentrations (above the critical micellization concentration (CMC)) and in the presence of some water. The effects of solvent quality on the copolymer micellization in an organic solvent and on the solubilization of water in such systems are examined here for representative poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO) and poly(butylene oxide)-b-poly(ethylene oxide) (PBO-PEO) copolymers. The solvent quality is modulated by the addition of cosolutes and by a change in the temperature. A number of notable observations are reported: Worsening the aqueous solvent conditions by the addition of NaCl (10 wt% with respect to water) almost doubles the CMC and the water solubilization capacity (WS) of a PEO-PPO-PEO copolymer in p-xylene. An increase in temperature makes water a worse and xylene a better solvent for the copolymer. The combined result of heating is an increase of the CMC for all three copolymers studied. This indicates that the formation of reverse micelles is exothermic, which is opposite to what has been observed for normal micelles. The effects of temperature on the water uptake are nonmonotonic: WS increased with temperature for a PEO-PPO-PEO copolymer with 40% PEO but decreased for a copolymer with 20% PEO. An increase in WS with temperature, followed by a decrease, with the maximum WS efficiency occurring at the "effective" cloud point of the copolymer is proposed in order to explain this observation. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367594 TI - Equilibrium Adsorption Studies of Some Aromatic Pollutants from Dilute Aqueous Solutions on Activated Carbon at Different Temperatures AB - Aqueous solutions of phenol, p-chlorophenol, and p-nitrophenol have been used to determine the adsorption isotherm for single solute systems on activated carbon at different temperatures. The experimental program has been conducted to investigate the influence of concentration and temperature. All the reported equilibrium isotherm equations have been tried on present and published experimental data. A generalized isotherm equation which was proposed by Khan et al. (6, 10) and tested for bi-solute adsorption data has been modified for single solute system. The temperature dependency has also been incorporated into a generalized equation. It has been noticed that the Radke and Prausnitz (7) and generalized isotherm equations could represent the entire data with a minimum average percentage error. The influence of different adsorbents, sorbate concentrations, and pH of aqueous solutions has also been discussed in detail. The temperature dependency has been investigated using both the Dubinin-Astakov (13) and the modified generalized equation. The generalized equation describes the experimental and published data adequately and provides a single value of differential molar heat of adsorption, DeltaHads, for a single solute adsorption system. The Dubinin-Astakov isotherm equation has shown an increasing trend of DeltaHads as the loading of adsorbent has increased. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367596 TI - Monolayer Assemblies and Optical Properties of Europium(III) Complexes with beta Diketones Containing Various Substituents AB - Europium(III) complexes with beta-diketones containing various substituents were newly synthesized and their monolayer behaviors on the water surface were studied in situ by a Brewster angle microscopy (BAM) together with surface pressure-area isotherms. Some BAM images look like a thin soap film on the flat surface, consisting of gas and liquid phases. The monolayer assemblies of these complexes could be deposited by both LB and horizontal lifting techniques. The emission probability from the excited singlet state 5D1 increased in the film as compared to the lowest excited state 5D0, and the symmetrically forbidden transition 5D0- >7F0 was enhanced in comparison with those in the solutions and the crystallines. This effect on the fluorescence was observed significantly for the complex with an asymmetrically substituted ligand rather than that with a symmetrically substituted one. These results can be ascribed to the fact that the thermal deactivation of the higher excited state is decreased and also the symmetries of these complexes are slightly distored in the monolayer assemblies. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367597 TI - Interactions between Talc Particles and Water and Organic Solvents AB - Three talc samples have been studied by adsorption and immersion methods after a classical characterization of their properties. The combination of adsorption isotherms and of immersion measurements allows the calculation of enthalpies and entropies of adhesion. The studied talcs are characterized as "middle energy" solids. The differences between the particle shapes of the different samples are shown to be of great importance, indicating a linkage between cristallinity and surface properties. The whole results are explained by the influence of intermolecular forces such as acid-base interactions in the interfacial layer. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367598 TI - Reductive Dissolution of Fe(III) (Hydr)oxides by Cysteine: Kinetics and Mechanism AB - Cysteine was used as a model reductant to gain further insight into the kinetics of bacterially mediated iron reduction. Our experimental data and modeling results indicated that the reductive dissolution of hydrous ferric oxide (HFO) takes place via surface complex formation of cysteine and corresponds to the rate law d[Fe(II)]/dt = k20[ identical withFecys-] + k21[ identical withFecys0], where k20 and k21 are the corresponding rate constants for the cysteine surface species identical withFecys- and identical withFecys0, respectively. The pH-dependent dissolution behavior of HFO suggested that k20[ identical withFecys-] >> k21[ identical withFecys0]. A value of 6.83 x 10(-2) s-1 as the lower limit for k20 was obtained. These two surface species were related by the following proton complexation equilibrium expression: identical withFecys- + H+ right arrow over left arrow ks-1ks1 identical withFecys0. A log Kints value of 7.5 was estimated for this equilibrium relationship, indicating a reduction of 2.8 pH units in the acidity constant of cysteine's amino group, following adsorption onto HFO. The reductive dissolution rate of HFO exhibited a maximum of 3.3 x 10(-8) mol s-1 m-2 at pH 8.3, corresponding to the pH value where the concentration of identical withFecys- species was at maximum. Experiments in the presence of phosphate indicated that at equilibrium concentrations as low as 50 MUM, this ligand brings about more than a sixfold reduction in the rate of dissolution of HFO by cysteine. Dissolution experiments with other iron oxide phases showed the following order for the reductive dissolution rates: HFO > lepidocrocite > goethite. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367599 TI - A New Topological Index for Molecular Probes Used in Inverse Gas Chromatography for the Surface Nanorugosity Evaluation AB - Inverse gas chromatography is currently used for the determination of the surface properties of divided solids by probing the surface with alkanes or polar molecules of known properties. This paper suggests the use of a new topological index for the description of the probe's (alkanes) geometry and hence of their accessibility to the solid's surface. The proposed index (chiT) derives from the well known Wiener index. The application of chiT for the determination of the dispersive component of the surface energy of pyrogenic silica, but also for the evaluation of the geometric heterogeneity of lamellar silica, is described. Further, goethite and zirconia samples were submitted to similar analysis. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367600 TI - A New Topological Index for Molecular Probes Used in Inverse Gas Chromatography AB - The application of the new morphological index chiT, which is an extension of Wiener's index for the evaluation of the retention data of apolar and polar solutes used in inverse gas chromatography, is described. Indeed, chiT performs satisfactorily, surpassing the other molecular descriptors employed so far. Examples of applications on silica and graphite samples are presented. It appears that the new index allows a unique evaluation of the Lewis acid-base surface characteristics of solid surfaces. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367601 TI - Theory of Electrode Polarization in Dielectrophoresis and Electrorotation AB - Experimental observations, previously reported in the low frequency regime of the spectrum in dielectrophoresis and electrorotation of plant protoplasts, have revealed serious discrepancies between the predictions of the "Shelled Model" and measurements. Much work has also been carried out in the theoretical realm to reconcile these discrepancies by introducing such mechanisms as charge flow on the surface of the cell and micromotion, but in all this the effects of electrode polarization have been neglected. Part of the problem lies in the rather formidable nature of the analysis that must be carried out with nonuniform fields since the entire system of governing partial differential equations must be considered. In the case of uniform fields it is convenient to formulate the problem in the language of ordinary differential equations. This problem is further exacerbated by the lack of a well defined boundary condition at the outer limit of the double layer. We have used the method of Green's functions, since this allows the consideration of partial differential equations in a more natural way than the other methods, in order to formulate the problem. The lack of a well defined boundary condition at the outer surface is dealt with by taking an integral transform of the governing equations and thus recovering a relationship between the applied and the far fields. The results of our analysis show that the double layer relaxation, in the selected model, is a very simple single relaxation process and its effect is to diminish the discrepancies between theory and experiment. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367602 TI - Theory of Electrode Polarization in Dielectrophoresis and Electrorotation AB - The analysis begun in the previous paper on the role of electrode polarization in experimental measurements using dielectrophoresis and electrorotation in a polar spherical coordinate frame is extended to include other curvilinear coordinate systems. The Green functions, as derived in the previous paper in terms of the Dyson equation, is shown to obey a variational theorem that allows the inclusion of the equilibrium potential and the Stern layer effect neglected thus far. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367603 TI - Interaction of ortho-Phospho-l-serine with Hydroxyapatite: Formation of a Surface Complex AB - ortho-Phospho-l-serine (H2Psi, where Psi represents the serinephosphato ion), a constituent of salivary proteins, seems to play an important role in the mineralization of teeth. To understand the basic mechanism of this interaction, the uptake of o-phospho-l-serine from relatively concentrated aqueous solutions (up to 100 mmol/L) onto synthetic hydroxyapatite was studied. Previous studies have shown that in the dilute concentration range (<12.5 mmol/L) the uptake followed a regular Langmuirian adsorption plot. At higher concentrations the uptake curve increased steeply, but no formation of a separate phase in the reacted apatite was discernible, either by optical or by scanning electron microscopy. The dissolution of apatite released phosphate and calcium ions into the solution in amounts linearly related to the uptake of serine with P/Psi = 1 and Ca/Psi = 2. The charge and mass balance of the reaction can be reconciled with the formation of the surface complex (shown within brackets):Ca10(OH)2(PO4)6 + 6H2Psi --> [Ca6(HPsi)2(HPO4)2(PO4)2] + 4Ca2+ + 2HPsi1- + 2Psi2- + 2H2PO1-4 + 2H2O.The formation of two other surface complexes is possible; however, the complex shown above probably disrupts the apatite lattice the least. Traces of CaPsi·H2O precipitate out from the filtrates of highly concentrated solutions after 6 days. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367604 TI - Hysteresis Thermodynamics of Capillary Condensation in Mesopores AB - A thermodynamic approach based on mass, energy, and entropy balances is developed for capillary condensation hysteresis in porous media. Processes of fluid condensation and evaporation are considered as quasi-isothermal irreversible transitions between equilibrium states of the capillary system. The corresponding balances express the equilibrium interfacial properties of the system through the work and heat measured in capillary process and, thus, may be used for evaluating the vapor-condensed phase interface area as a function of pressure, surface area of the porous solid, its pore size distribution, and surface fractal properties. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367605 TI - LETTER TO THE EDITOR AB - Particle dehydration and interparticle binding have been advocated to explain the coagulation of silica sols by alkaline salts. Those approaches are reexamined in the light of experimental data that have recently been published. It is proposed that coagulation of silica by alkaline cations, when it occurs, is caused by interparticle hydroxo bridging. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367606 TI - LETTER TO THE EDITOR AB - An isocyanurate silane coupling agent effectively attaches to E-glass fibers both from aqueous or CCl4 solution. SEM revealed remarkably different glass surface topographies that were solvent dependent. Application of the coupling agent from CCl4 solution gave rise to unprecendented polymeric bridges between adjacent parallel fibers. The existence of such large bridging structures has only recently been postulated, and it was not thought that such theoretical projections would ever be observed, as polymeric bridging structures typically should collapse in the absence of solvent. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367607 TI - Dependence of myocardial hypothermia tolerance on sources of activator calcium. AB - To determine the relationship between cardiac hypothermia tolerance and the sources of activator calcium, we selectively modified either the sarcolemmal calcium permeability by nifedipine or the sarcoplasmic reticulum function by caffeine in papillary muscles from both the rat, as a cold sensitive model, and the ground squirrel, Citellus dauricus, a deep hibernator. Both force-interval relationship and cooling performance were investigated. At 25 degrees C, the slope of the force-interval curve of the ground squirrel was nearly double that of the rat. At shorter test intervals 0.5 muM nifedipine moved the curve down with little effect at longer intervals, and the curve slope increased. Caffeine (1 mM) decreased the peak force and eliminated its dependence upon test interval. When the temperature was lowered, rat preparations showed a marked increase of resting tension and aftercontraction between 7 and 12 degrees C and became inexcitable. In contrast, they maintained contractility down to a few degrees above 0 degrees C without aftercontraction and increased resting tension in the ground squirrel. In the rat nifedipine shortened the contractions, prevented the increase of resting tension, and minimized aftercontractions, with little improvement of contractility. Caffeine prolonged the contractions, caused a striking increase of resting tension and aftercontractions, and finally disabled the contractility at about 5-10 degrees C, even in the ground squirrel. We conclude that depressed calcium influx helps to prevent hypothermic calcium overload of the cardiac cells. Good function of the sarcoplasmic reticulum is essential for tolerance of hypothermia by cardiac cells. A suggestion that may improve the hypothermic tolerance of the myocardium from nonhibernators is postulated. PMID- 9367608 TI - Synergistic enhancement of the postthaw growth of cryopreserved rice cells by oxygenated perfluorocarbon and pluronic F-68 AB - The beneficial effects were assessed of supplementing culture medium with oxygenated perfluorocarbon, both alone and in combination with 0.01 (w/v) Pluronic F-68, on the postthaw viability, following cryopreservation, of suspension cultured cells of the Japonica rice, Oryza sativa cv. Taipei 309. The mean viability, as assessed by triphenyl tetrazolium chloride reduction, of cells at 4 days after thawing was increased 20% over control by oxygenated perfluorodecalin (P < 0.05) in 100-ml glass jars and similarly by 24% (P < 0.01) when recovered on a smaller scale in 24-well petri dishes. In a separate assessment, a 21% increase above control treatments (P < 0.05) in postthaw viability was also observed with oxygenated perfluorodecalin. A similar, 36% increase (P < 0.05) in postthaw viability occurred with cells exposed to 0.01% (w/v) Pluronic F-68 alone. A more pronounced, synergistic increase in viability, up to 57% over control (P < 0.05), occurred with cells recovered in the presence of both oxygenated perfluorodecalin and 0. 01% (w/v) Pluronic F-68. No significant difference was observed between Pluronic F-68 and oxygenated perfluorodecalin treatments. Both the perfluorodecalin and the Pluronic F-68 treatments alone and in combination also promoted an increase in biomass, measured as fresh weight gain 30 days after thawing, to a maximum of 38% above control (P < 0.05). These results demonstrate the marked cytoprotectant effects of oxygenated perfluorodecalin and Pluronic F-68, both alone and/or in combination, for plant cells recovered from cryostorage. Such options offer alternative postthaw handling strategies to cells of those plant species which, normally, respond poorly to conventional recovery procedures. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367609 TI - Cultured lung epithelium: A cellular model for lung preservation. AB - Cellular models have helped with the development of conditions needed for hypothermic preservation of kidney, liver, and heart. Recently, highly differentiated cultured lung epithelial cell lines grown with basolateral side feeding technique have become available that can mimic airspace, epithelium, and interstitium of lung parenchyma. Cultured lung epithelium coupled with Ussing's short-circuit current technique was used as a cellular model system for lung preservation. A parametric study was conducted to correlate the effects of luminal fluid composition (University of Wisconsin (UW) solution and phosphate buffered saline) and storage gas (air vs nitrogen) at 4 degrees C for 24 h on postischemic electrogenic properties (transepithelial ion transport and resistance). The results showed that cells were better preserved with the UW solution on both sides as measured by their transepithelial resistance, an indicator of tight junction integrity (Rte approximately 65% of control values approximately 135 Omega cm2). In addition, they responded better to mediators that stimulate chloride secretion than cells preserved with other conditions. Cells preserved with no additional fluid on the apical side had substantially lowered Rte (<20%) than those preserved with an additional thin layer of fluid ( approximately 35-65%). This cellular model system is a realistic representation of lung epithelium and can provide an accurate assessment of preservation quality through the measurements of tight junction integrity and active ion transport. PMID- 9367610 TI - Vitrification properties of solutions of ethylene glycol in saline containing PVP, Ficoll, or dextran. AB - Vitrification solutions which are used for cells or embryos generally contain cryoprotectant, physiological saline, and one or more macromolecular solutes. The macromolecules modify the vitrification tendencies of these solutions, but there is little detailed information on the vitrification properties of ethylene glycol solutions containing the additives PVP, Ficoll, and dextran. This study therefore added ethylene glycol to 0.9% NaCl in water (saline) and used differential scanning calorimetry to determine the lowest concentration at which the solution would remain vitreous when a warming rate of 10 degrees C/min was used. In the absence of other additives 59 wt% ethylene glycol (EG) in saline formed a stable glass. When ethylene glycol was replaced by the polymers Ficoll and/or dextran on a weight for weight basis, the resulting solution vitrified less readily than an EG-saline solution even though the total solute concentration was kept constant. The total solute concentration required to form a stable vitreous solution increased as the Ficoll 70,000 and 400,000 MW or dextran 78,000 MW content increased (5, 10, and 20 wt%). Ficoll and dextran had little or no effect on the glass transition and melting points of the solutions. In the presence of PVP vitrification occurred at a total solute concentration of 59 wt% (PVP 360,000 MW) or 60 wt% (PVP 40,000 MW) for all three tested PVP concentrations (5, 10, and 20 wt%). Although this indicates that PVP and EG have comparable vitrification properties, the melting and the glass transition temperature of the solutions rose as the PVP content increased. When 1 m sucrose was added to saline and 0, 5, 10, or 20 wt% PVP 40,000 MW vitrification was achieved with 31, 26, 23, and 15% EG, respectively, indicating that the total solute concentration required for vitrification could be estimated with reasonable accuracy from the sum of the individual components. We conclude that the tested polymers differ in how they interact with ethylene glycol-based vitrification solutions. PMID- 9367611 TI - Osmotic behavior and transport properties of human islets in a dimethyl sulfoxide solution. AB - The osmotic responses of isolated human islets were evaluated using a perfusion cryomicroscope device. Individual islet volumes were measured following equilibration with a series of solutions of graded solute concentration. The osmotically inactive volume for human islets was determined to be 25% from a Boyle-van't Hoff plot of these data. A network thermodynamic model was developed via the bond graph method to describe the transport of water and cryoprotective agent in pancreatic islets. The model was curve fit to transient volumetric data for the response of islets to a stepwise exposure to 1 Me2SO at temperatures of 24.0, 3.0, or -3.5 degrees C. Standard membrane transport parameters (Lp, omega, sigma) and interstitial diffusion transport properties (kappa w, kappa p) were calculated from the fitting procedure. The temperature coefficients for membrane transport properties were expressed in terms of activation energies for water (ELp) and Me2SO (E omega). Osmotic challenge experiments conducted with fresh and cryopreserved human islets indicate that frozen/thawed islets exhibit a a slight increase in transport properties. PMID- 9367612 TI - Cryopreservation of mouse spermatozoa. I. Effect of seeding on fertilizing ability of cryopreserved spermatozoa. AB - To examine the effect of seeding to induce ice formation during cryopreservation on their survival, spermatozoa from B6D2F1 mice were cooled to and held at -4 degrees C for 30 min in phosphate-buffered saline (PBS) alone, in egg yolk supplemented PBS, or in PBS with raffinose + glycerol as cryoprotective additives (CPAs). Seeding and holding spermatozoa at -4 degrees C did not affect their viability as judged by vital staining. Egg yolk protected spermatozoa against chilling injury, as cooling them to -4 degrees C in the presence of egg yolk yielded higher survivals than those cooled without egg yolk (34.4 +/- 3.4 v 9.0 +/- 1.3% in three replicates of >400 spermatozoa/replicate). To study effects of seeding on their fertilizing ability, spermatozoa in the raffinose-glycerol-egg yolk solution were frozen to -196 degrees C either without seeding or after seeding at -4 degrees C. Development of 222 oocytes into two-cell embryos after in vitro fertilization (IVF) with spermatozoa frozen without seeding was 43%; development rates of 186, 186, and 207 oocytes after IVF with spermatozoa frozen after seeding and being held at -4 degrees C for 5, 10, or 30 min were 46, 44, and 9%, respectively. In a direct comparison, after IVF with seeded or unseeded spermatozoa the respective cleavage rates into two-cell embryos were 83% of 275 oocytes and 69% of 304 oocytes, a difference that was small but significant by chi2 analysis. An additional 925 oocytes were fertilized with spermatozoa after being seeded and frozen to -196 degrees C in four separate batches of CPA solutions. Overall, after IVF with frozen sperm, 68% of those oocytes cleaved into two-cell embryos and 59% developed into 544 blastocysts. Based on these results, we concluded that embryo production by IVF seemed to be improved using spermatozoa frozen after being seeded. Mouse spermatozoa cryopreserved by the method described here are capable of fertilizing oocytes at a rather high rate. PMID- 9367613 TI - Cryopreservation of mouse spermatozoa. II. Relationship between survival after cryopreservation and osmotic tolerance of spermatozoa from three strains of mice. AB - A procedure to cryopreserve mouse spermatozoa has been derived to bank the genetics of valuable strains of mice in a practical way. The primary objective of this study was to apply the cryopreservation method developed for spermatozoa of strain B6D2F1 to those of strains 129/J and C57BL6/J. Using the capability of spermatozoa to fertilize oocytes in vitro as the criterion of survival, we found differences in survival after cryopreservation among the three strains. Blastocysts were obtained after in vitro fertilization of oocytes with frozen spermatozoa from B6D2F1 (51%) and 129/J (12%); none was obtained from C57BL6/J. Transfer of embryos into recipients resulted in the birth of 69 live pups from 164 embryos produced with frozen B6D2F1 spermatozoa and 11 pups from 35 embryos produced with 129/J spermatozoa. To seek an explanation of these differences among the three strains, spermatozoa were exposed to anisotonic solutions ranging from 5 to 3200 mOsm; viability of spermatozoa was assessed by a double stain using flow cytometry. Mouse spermatozoa tolerated exposure to solutions of osmolalities between 200 and 400 mOsm, but were damaged when exposed to solutions exceeding this range. Spermatozoa from C57BL6/J were the most sensitive: 20, 35, and 40% of C57BL6/J, 129/J, and B6D2F1 spermatozoa survived exposure to an 800 mOsm solution, respectively. This study suggests that there is a genetic basis for sensitivity of mouse spermatozoa to osmotic shock and freezing injury. Nevertheless, the birth of live pups produced with frozen spermatozoa from 129/J as well as with spermatozoa from B6D2F1 mice indicates that cryopreservation of spermatozoa can be used to preserve the genetics of valuable strains of mice. PMID- 9367614 TI - Overwintering status and cold hardiness of hypera punctata AB - We investigated overwintering status and various characteristics related to cold hardiness in the clover leaf weevil, Hypera punctata. The larvae continue to feed and grow in winter. The proportion of late instar larvae in a field population increased gradually between December and the following March, and fourth (last) instar larvae were found in mid-February onward. The lower thermal threshold of development was lower in the larval stage than in the other developmental stages. The supercooling point (SCP) varied with developmental stages. There was a close positive correlation between the SCP and larval body weight. Deprivation of food for 3 days increased the correlation and decrease their SCP by 5 to 8 degrees C in larvae at any instar. The SCP of overwintering larvae did not differ from that of fed larvae in the laboratory. The food-deprived early instar larvae in the laboratory died without being frozen, while the lower lethal temperature of fed larvae in the laboratory and overwintering larvae were almost equivalent to the respective SCPs at a temperature normally encountered in the field. These suggested that this weevil may not increase their cold hardiness during winter so far and the SCP may serve as an indicator of cold hardiness. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID- 9367615 TI - Enhanced permeability of freeze-dried liposomal bilayers upon rehydration. AB - Until now, studies on the protection of liposomes against freeze-drying damage have mainly focused on the bilayer integrity during the freezing or drying step of this process. Here, we investigated the bilayer permeability of freeze-dried, lyoprotected liposomes to a nonbilayer interacting compound after rehydration, by monitoring the leak-in kinetics of externally added carboxyfluorescein (CF). The results showed that freeze-drying and rehydration of DPPC:DPPG 10:1 liposomes with sucrose in- and outside the vesicles caused a temporary increase in the bilayer permeability for CF, which leveled off after approximately 20 h. The amount of CF/mol phospholipid which leaked into the vesicles increased with vesicle size (range 0.1-1 micro m) / lamellarity. Reduction of the number of bilayers in 1-1 micro m) vesicles enhanced the permeability to CF after freeze drying and rehydration. The presence of CHOL decreased CF leak-in rates into 1 micro m MLVs consisting of DPPC:DPPG 10:1, but not into 0.1-micro m unilamellar vesicles. In the absence of sucrose similar leak-in profiles as a function of time were found after rehydration, suggesting that repacking processes of the bilayer were responsible for the enhanced permeability after freeze-drying and dehydration both with and without sucrose. The effect of size and lamellarity on the CF leak-in correlated with the retention of encapsulated CF after freeze drying and rehydration, but no correlation was found with the effect of lipid composition. Both small (0.1 micro m) lyoprotected liposomes made of DPPC:DPPG 10:1 and DPPC:DPPG:CHOL 10:1:4 were highly permeable during the rehydration step itself. The results indicate that, despite the presence of the lyoprotectant, "repacking" of the bilayer components takes place both during and after rehydration. This eventually leads to regaining of its barrier function. PMID- 9367616 TI - Cryopreservation of caprine beta-lactoglobulin transgenic mouse embryos. AB - As an economical and safer alternative to the maintenance of transgenic animals as live stocks, transgenic embryo cryobanks can be generated and maintained indefinitely. Two-cell embryos obtained from four lines of caprine beta lactoglobulin transgenic mice homozygous for the transgene were cryopreserved, and their response to cryopreservation-related stress was investigated. Significant differences between transgenic lines were found in the viability of frozen/thawed transgenic embryos and also in two-cell embryo production after superovulatory treatment of transgenic females. The results of this study suggest that cryopreservation protocols should be assessed on each transgenic line before the generation of transgenic embryo banks. PMID- 9367618 TI - Rudolf Wittenzellner (1921-1997) AB - Copyright 1997 Academic Press PMID- 9367617 TI - Bile duct warmer in hepatic cryosurgery--a pig liver model. AB - Freezing of the common bile duct resulted in injury, stenosis, or perforation of the bile duct in a dog model. Biliary cutaneous fistulas and bile leaks are reported as complications of hepatic cryosurgery in man. In an ex vivo pig liver model we compared freezing close to the bile duct with and without warming the bile duct with warmed saline solution via an inserted catheter ("bile duct warmer"). The recorded temperatures at the outer wall of the bile duct were -50 degrees C after 10 min of freezing without and 5. 8 degrees C with the use of the warmer (P < 0.001, two-way ANOVA). The bile duct warmer system may be a simple and inexpensive device in reducing perioperative morbidity after hepatic cryosurgery of hepatic liver lesions close to a bile duct. PMID- 9367619 TI - Specific intranucleolar distribution of Hsp70 during heat shock in polytene cells. AB - Hsp70, the most abundant and conserved heat shock protein, has been described as strongly concentrating in the nucleolus during heat shock. The important metabolic processes that take place in the nucleolus, rDNA transcription, processing, and assembling with ribosomal proteins, and the nucleolar architecture itself are very sensitive to temperature changes. In this work, we have analyzed in detail the nucleolar changes, in structure and activity, induced by temperature in Chironomus thummi salivary gland cells and the fine subnucleolar localization of Hsp70 during heat shock. The optimum temperature chosen to induce the heat shock response was 35 degrees C. Under these conditions transcription of heat shock genes, inactivation of previously active genes and maximum synthesis of Hsps take place, while survival of larvae and recovery were ensured. After 1 h at 35 degrees C, nucleoli change from a uniform control pattern to a segregated pattern of nucleolar components that can be observed even at the light microscopic level. The dense fibrillar component (DFC) and the granular component appeared perfectly differentiated and spatially separated, the former occupying mainly the central inner region surrounded by a rim of granular component. Hsp70 was specifically localized within the DFC upon heat shock as shown by immunolocalization by both light and electron microscopy. Pulse labeling with [3H]uridine proves that rRNA transcription continues during heat shock. The pattern of Hsp70 distribution within the nucleolus correlates with that of newly produced rRNA transcripts. Hsp70 also colocalizes with RNA polymerase I, both being restricted to the DFC. These data show that the DFC seems to be the intranucleolar target for Hsp70 in heat-shocked cells. We discuss these results in relation to the possible function of Hsp70 in the first steps of preribosome synthesis. PMID- 9367620 TI - Caspase-mediated apoptosis in AK-5 tumor cells: a cell-free study using peptide inhibitors and antisense strategy. AB - An in vitro system has been employed to study the apoptotic mechanisms in the AK 5 tumor which is a spontaneously regressing rat histiocytoma. Cytosolic extracts of tumor cells primed for apoptosis using dexamethasone and immune serum from tumor-regressing animals were able to induce apoptosis in intact nuclei and reproduce the classical morphological and biochemical features typical of apoptotic cells. The cleavage of lamin A and PARP to signature fragments by these extracts and the inhibition of the same using peptide inhibitors signify the pivotal role of ICE and ICE-related proteases in apoptosis. Lamin A cleavage was insensitive to YVAD but PARP cleavage was blocked by both YVAD and DEVD. Cell extracts derived from cells overexpressing the Bcl-2 gene and Nedd-2 antisense gene, respectively, failed to induce apoptosis in exogenously added nuclei, suggesting that Bcl-2 gene product is downregulating a key event in apoptotic cascade. The study also demonstrates the coherent action of different ICE-related proteases in apoptosis and their functional redundancy. This system may prove useful for analyzing complex molecular mechanisms underlying apoptosis in tumor cells. PMID- 9367622 TI - Chromosomal instability and telomere length variations during the life span of human fibroblast clones. AB - Growth characteristics, karyotype changes, and telomere length variations were analyzed during the life span of 12 anchorage-independent clones isolated from a xeroderma pigmentosum fibroblast strain. After an initial period of comparable active growth, all the clones showed a decline in the growth rate and finally entered a phase of replicative senescence; however, the number of population doublings and the time required to enter senescence varied among the clones. Repeated cytogenetic analyses during culture propagation showed the appearance of chromosome anomalies, mainly telomeric association (tas) and unbalanced translocations. In all the clones the percentage of abnormal mitoses increased with culture passage, but reached different levels (from less than 10% to about 100%). This finding indicates that the replicative block may be associated with differently altered cytogenetic patterns. Specific chromosome arms (5p, 16q, 19q, and 20q) were preferentially involved in tas, suggesting that alterations in chromosome ends may occur which predispose to fusion. In some clones it was possible to demonstrate the origin of marker chromosomes from the evolution of tas. Telomere length analysis by Southern blotting on DNA samples prepared from 7 clones and from the parental cell lines showed that the terminal restriction fragment (TRF) profiles were homogeneous in senescent parental cells and in the clones during the last part of their life in culture, regardless of the degree of karyotype abnormalities. The homogeneity of the TRF profiles supports the hypothesis of a critical telomere length at senescence. PMID- 9367621 TI - Expression of nuclear lamins in human tissues and cancer cell lines and transcription from the promoters of the lamin A/C and B1 genes. AB - We have examined the expression of lamins A, B1, and C in human tissues and cancer cell lines and the function of the lamin A/C and B1 gene promoters in transfected cells. Northern analysis and immunoblotting demonstrated that lamin A/C mRNA and protein were not detectable in some human cell lines whereas lamin B1 was always present. Sequencing of approximately 2.6 kb of the lamin A/C and 1.6 kb of the lamin B1 genes 5' to the translation initiation sites showed that they did not contain typical TATA boxes near the transcription start sites. The lamin B1 and A/C proximal promoter regions were transcribed in transfected HeLa, Raji, and NT2/D1 cell lines even if the cells did not contain detectable endogenous lamin A/C mRNA or protein. These results show that, similar to most cytoplasmic intermediate filament genes, transcriptional regulatory elements in the promoters of the human nuclear lamin A/C and B1 genes do not control their cell type-specific expression in culture lines. PMID- 9367623 TI - A cytofluorometric assay of nuclear apoptosis induced in a cell-free system: application to ceramide-induced apoptosis. AB - Purified nuclei exposed to apoptogenic factors in vitro undergo morphological and biochemical changes in chromatin organization. Most cell-free models of nuclear apoptosis are based on the quantitation of endonuclease-mediated DNA fragmentation on agarose gels or on the changes of nuclear morphology revealed by the DNA-intercalating fluorochrome 4'-6-diamidino-2-phenylindole dihydrochloride. In this work we develop a cytofluorometric system for the accurate quantitation of nuclear DNA loss. This system has been used to determine the conditions of nuclear apoptosis induced by apoptosis-inducing factor (AIF) contained in the supernatant of mitochondria induced to undergo permeability transition. AIF can provoke significant nuclear DNA loss in < or = 5 min, acts over a wide pH range (pH 6 to 9), and resists cysteine protease inhibitors such as iodoacetamide and N ethylmaleimide. Moreover, we applied this system to the question of how the proapoptotic second messenger ceramide would induce apoptosis in vitro: via a direct effect on nuclei, a direct effect on mitochondria, or via indirect mechanisms? Our data indicate that ceramide has to activate yet unknown cytosolic effectors that, in the presence of mitochondria, can induce nuclear apoptosis in vitro. PMID- 9367624 TI - Human and murine high endothelial venule cells phagocytose apoptotic leukocytes. AB - Apoptotic cell death occurs during normal lymphocyte development and differentiation as well as following lymphocyte exposure to endogenous corticosteroids released during stress, malnutrition, and trauma. Recognition and engulfment of these apoptotic cells is important for the clearance of dying cells before they release potent inflammatory mediators into the vasculature or tissues. Phagocytosis of apoptotic cells is accomplished in part by macrophages. We report for the first time that apoptotic lymphocytes are also phagocytosed by high endothelial venule (HEV) cells. The murine HEV cell line mHEVa rapidly phagocytosed apoptotic lymphoid and myeloid cells with the greatest rate of phagocytosis occurring at 0-6 h. To confirm HEV cell interaction with apoptotic cells, we demonstrated that apoptotic human tonsil lymphocytes were phagocytosed by human tonsil HEV cells in primary cultures. Furthermore, we examined HEV cell phagocytosis in vivo. Mice were treated with a natural corticosterone (4-pregnene 11 beta,21-diol-3,20-dione) at levels detected during stress or malnutrition (93 180 micrograms serum cortisol/dl). At 4-12 h posttreatment, apoptotic lymphocytes were present inside vacuoles of HEV cells in axillary lymph node tissue sections, as determined by transmission electron microscopy. These data suggest that, in addition to macrophages, lymph node HEV cells also play a role in the removal of apoptotic lymphocytes. Moreover, since HEV cells are specialized endothelial cells that regulate lymphocyte migration into peripheral lymphoid tissues, they may provide an important checkpoint for clearance of apoptotic lymphocytes within the vasculature, as well as limiting entrance of nonfunctional lymphocytes into the lymph node. PMID- 9367625 TI - Differential expression of neuroD in primary cultures of cerebral cortical neurons. AB - We have investigated the expression patterns of a basic helix-loop-helix regulatory gene, neuroD, in primary cultures of murine cerebral cortical neurons. The differentiation states of neurons in primary cultures were determined by the sensitivity of neurons to glutamate toxicity and the expression of specific proteins such as the phosphorylated form of a 200-kDa neurofilament, HPC 1/syntaxin 1A, and cell adhesion molecule L1. The expression of neuroD was determined by RT-PCR analysis and in situ hybridization. The experimental results thus obtained revealed that neuronal maturation is initiated between Day 7 and Day 11 in the culture as already known, and that the expression of neuroD decreases with increasing days in culture. Based on these findings, it was concluded that neuroD is expressed in immature neurons but not in mature ones. PMID- 9367626 TI - Establishment and characterization of a nontumorigenic cell line derived from a human hepatocellular adenoma expressing hepatocyte-specific markers. AB - In the present study the establishment and characterization of a nontumorigenic liver epithelial cell line (HACL-1) derived from a human hepatocellular adenoma is described. The HACL-1 cells have a finite life span (i.e., they proliferate for a period of 2 months and then senesce), show cell-cell contact inhibition, do not grow in soft agar, are not tumorigenic when injected in nude mice, and possess a normal diploid karyotype. The cultured cells resemble hepatocytes, but exhibit some features of dedifferentiation. At the ultrastructural level the cells are endowed with round or oval nuclei, abundant cytoplasmic organelles, and varying amounts of glycogen. The rough endoplasmic reticulum is disorganized, while peroxisomes and matrix granules within mitochondria are lacking. HACL-1 cells are cytokeratin 18-positive as well as (transiently) albumin- and alpha fetoprotein-positive, but do not express cytokeratin 19. Furthermore, no mutations were observed in exons 5-8 of the tumor suppressor gene p53. Taken together these results show that HACL-1 cells are nontumorigenic proliferating liver epithelial cells, which might prove to be of great value in future studies on diverse aspects of human liver cell biology and carcinogenesis. PMID- 9367627 TI - Signaling pathways involved in dephosphorylation and localization of the actin binding protein cofilin in stimulated human neutrophils. AB - We have studied activation-induced dephosphorylation of proteins in human neutrophils loaded with [32P]orthophosphate using two-dimensional gel electrophoresis and autoradiography. A major phosphoprotein of 20 kDa in resting neutrophils was markedly dephosphorylated upon activation of cells with chemotactic peptide or phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C (PKC). Using a monoclonal anti-cofilin antibody, this phosphoprotein could be shown to be identical with cofilin, a protein implicated in actin filament remodeling. Signaling pathways leading to this dephosphorylation were further characterized. To define the role of PKC isoforms in cofilin dephosphorylation, we used different PKC inhibitors. Go 6976 (10 microM), which inhibits preferentially PKC alpha and beta, did not prevent PMA induced dephosphorylation of cofilin, whereas Ro 31-8220 and CGP 41,251 (10 microM), which act also on Ca(2+)-independent PKC isoforms, almost completely suppressed this event. The lack of effect of Go 6976 was not due to insufficient entry into the cells, as this drug suppressed PMA-induced increases in protein phosphorylation. Ca(2+)-independent PKC isoforms, rather than PKC alpha or beta, may thus be involved in PMA-induced cofilin dephosphorylation. In contrast, Ro 31 8220 did not inhibit chemotactic peptide-induced cofilin dephosphorylation, suggesting here a PKC-independent pathway. The phosphatase inhibitor okadaic acid (1-2 microM) attenuated phosphorylation of cofilin in resting cells. This reduced level was not further attenuated by PMA. Phosphatases 1 and/or 2A may thus control cofilin phosphorylation in resting cells and contribute to PMA-induced cofilin dephosphorylation. Dephosphorylation of cofilin induced by PMA, chemotactic peptide, or okadaic acid was always accompanied by a shift of cofilin to the cell periphery into F-actin-rich areas. These findings suggest a role of cofilin in stimulus-dependent actin remodeling in motile neutrophils. PMID- 9367628 TI - Oxidized low-density lipoproteins affect natural killer cell activity by impairing cytoskeleton function and altering the cytokine network. AB - Several lines of evidence indicate that oxidative imbalance can play an important role in determining an impairment of natural killer (NK) cell activity in a variety of human diseases. Because a specific role for oxidized low-density lipoproteins (LDL) as pro-oxidizing agents has been envisaged, we tested the activity of oxidized LDL (ox-LDL) on NK cell-mediated cytotoxicity, cytokine release, and membrane molecule modulation. Native LDL served as control. Treatment with ox-LDL at noncytotoxic concentrations (0.2 mg/ml) during the NK/target cell (TC) interaction markedly reduced NK cytotoxic activity against U937 tumor cells. This inhibitory activity was also noticed when NK cells were pretreated with ox-LDL. Scanning electron microscopy examination of NK-target cell conjugates failed to reveal any morphological cell damage. In addition, the number of conjugates and the expression of some adhesion molecules (CD11a, CD11b, CD18, CD2, and CD62L) were not modified by ox-LDL. These observations argued against a possible interference of ox-LDL with the binding process leading to the formation of NK/TC conjugates. By contrast, immunocytochemical analyses of cytoskeleton components of NK cells exposed to ox-LDL showed a partial depolymerization and a derangement of the microtubular apparatus. These alterations were accompanied by an evident decrease in their intracellular reduced glutathione content. Owing to the important role played by the microtubular network during the killing process, it is possible to infer that a cytoskeleton alteration underlies the inhibitory activity of ox-LDL on NK cell function. In addition, exposure of mitogen-stimulated peripheral blood mononuclear cells to ox-LDL markedly reduced specific mRNA transcription and release of cytokines relevant for NK cell activity (such as tumor necrosis factor alpha, interferon gamma, and interleukin 12). These data suggest that the impairment of NK cell activity by ox-LDL likely reflects the concomitant dysregulation of some essential mechanisms of NK cell function. PMID- 9367630 TI - Nuclear domains in skeletal myotubes: the localization of transferrin receptor mRNA is independent of its half-life and restricted by binding to ribosomes. AB - The retention of mRNAs near the nuclei that synthesize them may be an important feature of the organization of multinucleated skeletal myotubes. Here, we assess the possible role of two factors in this localization. First, we examine the role of mRNA half-life, by studying the distribution of the mRNA for the transferrin receptor (TfR), whose half-life can be manipulated in culture by changing the availability of iron. In situ hybridization of myotubes of the mouse muscle cell line C2 shows that TfR mRNA is concentrated in the core of the myotubes. Its distribution around the nuclei is often asymmetric and its concentration changes abruptly. Stable transcripts display the same asymmetric localization as unstable ones, suggesting that half-life does not determine subcellular localization of TfR mRNA. Differential effects of the protein synthesis inhibitors puromycin and cycloheximide suggest that the mRNA is retained in position by its association with ribosomes. We then examine the distribution of the rough endoplasmic reticulum (RER) and find it to be broader than the distribution of TfR mRNA. In contrast to TfR mRNA, the mRNA for a secreted immunoglobulin kappa light chain has a more uniform distribution. Taken together, the results suggest that TfR mRNA may associate with RER subdomains by specific targeting. PMID- 9367629 TI - Histone synthesis in Trypanosoma cruzi. AB - Trypanosoma cruzi is an ancient, parasitic eukaryote which does not undergo chromatin condensation during cell division. This behavior may be explained if one considers the strong amino acid sequence divergence of Trypanosoma histones compared to higher eukaryotes. In the latter organisms histone synthesis is coupled to DNA replication. Considering the nonconserved amino acid sequence of T. cruzi histones, as well as the absence of chromatin condensation in this organism, we have studied histone synthesis in relation to DNA replication in this parasite. We have found that core histones and a fraction of histone H1 are synthesized concomitantly to DNA replication. However, another fraction of histone H1 is constitutively synthesized. PMID- 9367631 TI - Accumulation of WGA receptors in the cleavage furrow during cytokinesis of sea urchin eggs. AB - Sea urchin eggs stained with fluorescein-conjugated wheat germ agglutinin (F-WGA) before or after fixation showed a marked accumulation of fluorescence at the cleavage furrow in the first and the second cell divisions. WGA receptors (WGA binding membrane glycoproteins) were redistributed to the equatorial region through several steps in compressed eggs. Accumulated WGA receptors showed a distribution similar to that of contractile-ring microfilaments throughout most of the steps. Therefore, the former is probably associated with the latter directly or indirectly. Labeling with F-WGA provides a simple method to detect contractile-ring microfilaments in living eggs. Treatment of eggs with colcemid shortly before cytokinesis dispersed the ring-like accumulation of WGA receptors together with contractile-ring microfilaments. This result suggests that microtubule structures, probably asters, are involved in the redistribution of WGA receptors. Cytochalasin B prevented furrowing when it was applied shortly before cytokinesis. While contractile-ring microfilaments showed a spotty distribution in the expected furrow region, WGA receptors were normally redistributed. Furthermore, a higher concentration of the drug allowed the appearance of accumulated WGA receptors in compressed eggs although the development into a ring-like configuration was inhibited. These observations suggest the possibility that the redistribution of WGA receptors is involved in the formation of contractile ring. PMID- 9367632 TI - The high-mobility group protein T160 binds to both linear and cruciform DNA and mediates DNA bending as determined by ring closure. AB - The high-mobility group protein T160 was isolated by screening a phage library from a murine pre-B-cell line L1210. South-Western experiments have previously shown that this protein binds to V-(D)-J recombination signal sequences, suggesting that it may be a sequence-specific DNA-binding protein. However, neither gel-shift nor footprinting analyses have been successfully employed with the T160 protein, despite an extensive effort. In this study, the T160 protein or truncated forms made soluble through denaturing and renaturing cycles in urea were successfully used in gel-shift experiments showing that T160 binds to cruci form or linear duplex DNA with no apparent sequence specificity. Furthermore, fragments longer than 100 bp efficiently formed covalently closed circular monomers in the presence of T160 and T4 DNA ligase, indicating that the protein is capable of introducing bends into the duplex. Last, tissue distribution by Western blotting analysis showed that the T160 protein is expressed in various murine tissues in addition to those of lymphoid origin. Considering its broad evolutionary conservation (from plants to mammals) also, these results suggest that the functional role of the T160 protein is not limited to V-(D)-J recombination, but might be involved in basic processes such as DNA replication and repairing, where irregular DNA structures are generated and very likely recognized by HMG domain proteins. PMID- 9367634 TI - Expression of retinoid X receptors in human dermal fibroblasts. AB - Retinoic acid (RA) is known to exert profound effects on growth and differentiation in human dermal fibroblasts. In the observations presented here, we examined the regulation of expression of members of the RXR multigene family in human dermal fibroblasts. We showed that the messenger RNAs for both RXR alpha and RXR beta are expressed in human fibroblasts, but that the messenger RNA for RXR gamma is not detectable in these cells. Electrophoretic mobility shift studies of binding to the beta 2RARE in human dermal fibroblasts demonstrated that a single complex binds to beta 2RARE in the absence of RA. Stimulating cells with all-trans RA induced a second complex. An antibody to the RXR beta protein supershifted both complexes, while an antibody to the RXR alpha S/B protein had no effect on the binding. These data demonstrate that RXR beta plays an important role in retinoid-regulated signal transduction pathways in human dermal fibroblasts and the regulation of expression of the RXR gene family is different from that of the RAR gene family. PMID- 9367633 TI - Degradation of connexin43 gap junctions involves both the proteasome and the lysosome. AB - Intercellular communication may be modulated by the rather rapid turnover and degradation of gap junction proteins, since many connexins have half-lives of 1-3 h. While several morphological studies have suggested that gap junction degradation occurs after endocytosis, our recent biochemical studies have demonstrated involvement of the ubiquitin-proteasome pathway in proteolysis of the connexin43 polypeptide. The present study was designed to reconcile these observations by examining the degradation of connexin43-containing gap junctions in rat heart-derived BWEM cells. After treatment of BWEM cells with Brefeldin A to prevent transport of newly synthesized connexin43 polypeptides to the plasma membrane, quantitative confocal microscopy showed the disappearance of immunoreactive connexin43 from the cell surface with a half-life of approximately 1 h. This loss of connexin43 immunoreactivity was inhibited by cotreatment with proteasomal inhibitors (ALLN, MG132, or lactacystin) or lysosomal inhibitors (leupeptin or E-64). Similar results were seen when connexin43 export was blocked with monensin. After treatment of BWEM cells with either proteasomal or lysosomal inhibitors alone, immunoblots showed accumulation of connexin43 in both whole cell lysates and in a 1% Triton X-100-insoluble fraction. Immunofluorescence studies showed that connexin43 accumulated at the cell surface in lactacystin treated cells, but in vesicles in BWEM cells treated with lysosomal inhibitors. These results implicate both the proteasome and the lysosome in the degradation of connexin43-containing gap junctions. PMID- 9367635 TI - t-complex-associated embryonic surface antigen homologous to mLAMP-1. I. Biochemical and molecular analyses. AB - Previously we described an embryonic cell surface glycoprotein, ESGp, associated with the t-embryonic lethal alleles of the mouse t complex. This antigen is expressed on the cell surface of both early mouse embryos and embryonal carcinoma (EC) cell lines. The antigen is localized to areas of cell-cell contact in EC lines and redistributes to the outer edges of the blastomeres during compaction, thereby indicating a potential role in embryonic cell-cell interaction. We now report that this t-complex-associated ESGp is homologous to the mouse lysosomal associated membrane protein-1 (LAMP-1). Limited protein sequence analyses of the amino terminal and an internal peptide indicate considerable homology with the LAMP-1 protein. Biochemical parameters such as protein core size, sulfation and phosphorylation status, and resistance to proteolysis also demonstrate homology. While we detect only a single message with a mouse LAMP-1 cDNA probe via Northern blotting, Southern analyses indicate the existence of at least two homologous LAMP-1 genes. Additionally, we present evidence suggesting that ESGp/LAMP-1 serves as a substrate which may be differentially glycosylated by the activities of the gene products of the different t-lethal alleles. PMID- 9367636 TI - t-complex-associated embryonic surface antigen homologous to mLAMP-1. II. Expression and distribution analyses. AB - We have previously demonstrated that a mouse t-complex-associated antigen (ESGp) is present on the cell surface, specifically at areas of cell-cell contact, of cleavage stage embryos and embryonal carcinoma cell lines. In the accompanying paper, we document isolation, purification, and partial sequencing of this molecule. Amino-terminal and internal peptide fragments are highly homologous to the mouse lysosomal-associated membrane protein-1 (mLAMP-1). We also demonstrate considerable similarity, though not necessarily identity, between these two antigens through both biochemical and molecular analyses. In this report we use immunological techniques to compare the expression and distribution of these antigens in various cell lines as well as mouse tissues and preimplantation stage embryos. The data presented indicate that there are: (1) different antigenic forms of the ESGp/ mLAMP-1 homologues and (2) changes in the molecular composition and expression of these forms during embryogenesis and differentiation. It is obvious from these studies that mLAMP-1 is not strictly a static molecule whose sole function is to protect the lumenal side of the lysosomal membrane but rather is a dynamic molecule of potential import in many other cellular and organismal functions. PMID- 9367637 TI - Effects of hypophyseal hormones on transcription and RNA export to the cytoplasm. AB - The effects of hypophyseal hormones on RNA transcription and export to the cytoplasm were evaluated by means of light microscopic quantitative autoradiography. Normal or hypophysectomized rats as well as hypophysectomized animals treated with the follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone (TSH), or adrenocorticotropic hormone (ACTH), were used and the corresponding target cells (Sertoli cells, Leydig cells, epithelial thyroid gland cells, or adrenal cortical cells, respectively) were analyzed. Moreover, the variations of the concentration of perichromatin granules were correlated with the changes of the nuclear and cytoplasmic RNA labeling. Hypophysectomy causes a decrease of nuclear and cytoplasmic labeling and a large increase of the number of perichromatin granules in the four cell types studied. The administration of any of the four hormones brings about an increase in the rate of RNA transport to the cytoplasm in the target cells, within short periods (15 to 135 min). This augmentation of the RNA export takes place before any significant increase of the transcription rate, suggesting that the exiting RNA was previously stored in the nucleus. This is in agreement with a decrease of the number of perichromatin granules detected as early as 30 min after the administration of the hormones. Previous work demonstrated that steroid hormones such as estradiol and testosterone have similar effects on their target cells. All these observations indicate that the regulation of the RNA transport to the cytoplasm is an important means of rapid posttranscriptional modulation of the expression of genetic information that can mediate the early action of various regulatory factors. PMID- 9367638 TI - Reduction in fibronectin expression and alteration in cell morphology are coincident in NIH3T3 cells expressing a mutant E2F1 transcription factor. AB - Fibronectin within the extracellular matrix plays a role in cell attachment, spreading, and shape, while it also affects aspects of cell proliferation. Transcription factors such as E2F1 are also known to regulate cell shape and cell proliferation. Yet, to date no linkage has been established between fibronectin expression and E2F1. We show here that cells constitutively expressing a mutant E2F1 protein (E2F1d87) produce reduced amounts of fibronectin mRNA and protein. The altered expression of fibronectin seen in the E2F1d87 expressing cells is due, in part, to a reduction in transcription from the fibronectin promoter. Providing exogenous fibronectin, but not Type I collagen or laminin, as a substrate for cell adhesion is sufficient to revert the altered morphology and reestablish actin-containing microfilaments lost in the mutant cell line. An additional characteristic of the cells expressing the mutant E2F1 is that they demonstrate slow growth and a doubling in S phase duration. While providing exogenous fibronectin as an adhesion substrate did not shorten the S phase duration in the mutant line, it did significantly shorten the S phase duration in the parental NIH3T3 cell line, implicating a role for the extracellular matrix in regulating S phase transit in normal cells. PMID- 9367639 TI - Localization of adenosine receptor messenger RNAs in the rat eye. AB - Adenosine is present in all cells and body fluids and has been suggested to play several roles in the physiology of ocular tissues. The present study was undertaken to determine which types of adenosine receptor mRNAs are present in the rat eye, and where they are expressed. RNA or deoxyoligodeoxynucleotides complementary to rat adenosine receptor subtypes A1, A2A, A2B and A3 were used to generate 35S labeled antisense and sense probes. The probes were then used for in situ hybridization on 10 microm cryosections of the rat eye including the cornea, iris, ciliary body, lens, retina, choroid and sclera. A1, A2A and A2B receptor mRNAs were demonstrated in the ciliary processes. A1 receptor mRNA was also expressed in the ganglion cell layer of the retina. The retina also showed A2A receptor mRNA expression, which was most prominent in the inner nuclear layer and less prominent in the ganglion cell layer and outer nuclear layer. Weak A2A expression was found in the retinal pigment epithelium and choriocapillaris. No significant expression of A3 receptor mRNA was found in the rat eye. In conclusion, using in situ hybridization, we have demonstrated expression of mRNA for A1, A2A and A2B adenosine receptors in the rat eye. The expression patterns support specific roles for adenosine in the ciliary process and retina. PMID- 9367640 TI - Hyaluronan localization in tissues of the mouse posterior eye wall: absence in the interphotoreceptor matrix. AB - The distribution of hyaluronan (HA) in the posterior eye wall from the vitreous through the sclera, with special consideration to localization in the retina and interphotoreceptor matrix (IPM), was evaluated in mouse tissues using an HA specific probe (bHABC, biotinylated hyaluronan binding complex). The vitreous body was positive for HA, as was Bruch's membrane, expansive areas within the choroid, sclera and perimysial connective tissue of extraocular muscle. No HA staining was detected in the IPM or in any other retina layer except for the basal lamina (inner limiting membrane of the retina) which abuts the vitreous. Predigestion of sections with trypsin or chondroitinase ABC before bHABC application did not produce additional HA-staining in the retina or IPM. PMID- 9367641 TI - Towards a molecular understanding of phase separation in the lens: a comparison of the X-ray structures of two high Tc gamma-crystallins, gammaE and gammaF, with two low Tc gamma-crystallins, gammaB and gammaD. AB - gamma-Crystallins, although closely related in sequence, show intriguing differences in their temperature-dependent interactions: those that have a high or intermediate Tc for phase separation are cryoproteins whereas low Tc gamma crystallins are not. To address the molecular basis of phase separation, X-ray crystallography has been used to define the structural differences between high and low Tc gamma-crystallins. A pre-requisite for this study was to clarify the assignment of bovine gene sequences to bovine gamma-crystallin proteins used for biophysical measurements. Based on nucleotide sequence analyses of gamma E and gamma F bovine crystallin genes, gamma F corresponds to the previously crystallised high Tc protein bovine gamma IVa and gamma E corresponds to the high Tc bovine protein fraction previously known as gamma IIIa. The gamma F sequence has enabled the completion of the refinement of the bovine gamma F crystal structure which shows that the molecule has an additional surface tryptophan explaining why gamma F has different spectroscopic properties from gamma B. A high Tc protein from rat lens, gamma E crystallin, has been crystallised and the X-ray structure solved at 2.3 A resolution. Comparison of the X-ray structures of two high Tc proteins, rat gamma E and bovine gamma F, with the structures of two low Tc proteins, bovine gamma B and bovine gamma D, shows that the main conformational change between high and low Tc proteins is in the cd surface loop of motif 3. All four structures have numerous ion pairs on their surfaces leading to a high surface charge density, yet with low overall charge. Comparison of the lattice contacts of the two high Tc proteins with the two low Tc gamma crystallins indicates that these high Tc proteins utilise more amino-aromatic interactions such as between histidine and arginine. Comparison of the sequences of all the gamma-crystallins which have been characterised for phase separation temperature indicates that only residue Arg/Lys 163 uniquely distinguishes cryo from non-cryo gamma-crystallins and it is close to the altered surface loop. Although this region probably contributes to phase separation, Tc is likely to be a function of an overall global property that is responsive to overall charge distribution. Calculated dipole moments of native gamma-crystallins, low Tc gamma crystallin sequences threaded into high Tc gamma-crystallin structures, and vice versa, show how both sequence and 3D structure contribute to this overall property. High Tc gamma-crystallins have on average higher Arg/Lys ratios and higher histidine content. It is hypothesised that this increases the proportion of surface static paired charged networks which thus reduces the repulsive hydration force and so increases the attractive interactions of the protein-rich phase in binary liquid phase separation. PMID- 9367642 TI - The role of cellular immunity both in the induction and effector phases of experimental allergic blepharoconjunctivitis (EAC) in rats. AB - In allergic conjunctivitis, the early phase reaction has been studied extensively both in humans and animals. Although cellular infiltration is the main feature of the late phase reaction, the role of cellular immunity remains unclear. The purpose of this study was to elucidate the role of cellular immunity both in the induction and effector phases of experimental allergic blepharoconjunctivitis (EAC). To analyse the involvement of cellular immunity in the induction phase, 6 8-week-old male Lewis rats were immunized with ovalbumin (OVA) emulsified with complete Freund's adjuvant (CFA), incomplete Freund's adjuvant (IFA), TiterMaxR (TM), aluminum hydroxide [Al(OH)3], or without any adjuvant. Three weeks after immunization, the rats were challenged with OVA by eye drops, and 24 hr later they were euthanized and their eyes, including the lids, blood, and lymph nodes were harvested for analysis of disease and immune responses. The results indicated that adjuvants were necessary to induce disease as well as both cellular and humoral immunity. Al(OH)3, CFA and TM induced stronger disease and cellular immunity than IFA. The intensity of disease correlated with that of cellular immunity. To further investigate the involvement of cellular immunity in EAC, lymph node cells collected from immunized rats were adoptively transferred into naive syngeneic recipients that were challenged 4 days later with OVA. EAC developed in the recipients of lymph node cells that were also stimulated in culture with OVA. These recipient rats developed cellular infiltration in the lid and conjunctiva, in a dose-dependent manner. These results suggest that cellular immunity played a major role in the development of EAC, both in the induction and effector phases. PMID- 9367643 TI - Lipofuscin in the retina: quantitative assay for an unprecedented autofluorescent compound (pyridinium bis-retinoid, A2-E) of ocular age pigment. AB - The pyridinium bis-retinoid, A2-E, has been discovered as one of the major autofluorescent components of retinal pigment epithelial lipofuscin. Due to its chemical characteristics, A2-E may contribute to cellular and molecular changes leading to age-related macular degeneration. Because A2-E is the first lipofuscin component that has been identified, purified, and its structure analysed, it represents an important marker molecule for studying lipofuscin formation under various conditions. In order to investigate the role of A2-E in ageing processes of the retinal pigment epithelium, we developed an HPLC assay for this compound using single wavelength UV-absorbance detection with continuous light emission. Standard A2-E was synthetized and purified by sequential TLC. In our assay, A2-E can be detected in amounts lower than 10 pmol. The assay has been applied to quantitative determination of A2-E amounts in albino rat eyes of different age groups. Our results demonstrate that there is a marked increase of A2-E levels in older animals. The method described is the first to allow quantification of this unusual retinoid from small amounts of biological samples. PMID- 9367644 TI - Induction of human thioredoxin in cultured human retinal pigment epithelial cells through cyclic AMP-dependent pathway; involvement in the cytoprotective activity of prostaglandin E1. AB - Human thioredoxin is one of the oxidative stress-inducible proteins and has a protective function against oxidant-induced injury. To evaluate the possible involvement of thioredoxin in the cytoprotective function of prostaglandin E1, we analysed the effect of prostaglandin E1 on cellular injury by hydrogen peroxide and intracellular thioredoxin induction. Cellular survival of human retinal pigment epithelial cell line, established from normal retinal pigment epithelial cells, following exposure to hydrogen peroxide was markedly improved by pretreatment of 1 microm prostaglandin E1. Thioredoxin expression was augmented in a dose-dependent manner when retinal pigment epithelial cells were pretreated with 10 nm-1 microm prostaglandin E1 1 hr before the exposure to hydrogen peroxide. Intracellular cyclic AMP level was elevated by Prostaglandin E1 when the cells were simultaneously exposed to hydrogen peroxide. Forskolin, an activator of adenylate cyclase, and dibutylyl cAMP, a cyclic AMP analog, could also induce thioredoxin and extend survival of retinal pigment epithelial cells. On the other hand, thioredoxin induction and cellular protection by prostaglandin E1 was blocked by Rp diastereoisomer of cyclic adenosine 3', 5', monophosphorothioate, a competitive inhibitor of cyclic AMP dependent protein kinase. Thioredoxin induction was augmented significantly by pretreatment with prostaglandin I2, a stimulator of cyclic AMP dependent signal pathway, while treatment with prostaglandin F2alpha, a stimulator of inositol phosphate dependent signal pathway, failed to enhance thioredoxin. These findings indicate that prostaglandin E1 has a cytoprotective activity against oxidative injury, partly through thioredoxin induction via cyclic AMP dependent pathway. PMID- 9367645 TI - pH-induced reversible dissociation of tetrameric duck lens delta-crystallin. AB - Animal lenses constitute many soluble proteins, which play a prominent role in eyes' light transparency. delta2-Crystallin, one of the major taxon-specific crystallins in duck lens, is a tetrameric protein consisting of four identical subunits, which contain endogenous argininosuccinate lyase activity. Under a neutral pH environment in this work, the protein was cross-linked with glutaraldehyde as tetrameric and dimeric forms with tetramer as the major form. Under acidic conditions, the protein was time-dependently dissociated into monomers with amino acid residues of pKa values 6.29+/-0.45 and 7.17+/-0.49 being involved in the monomer-monomer interactions and 6.20+/-0.10 and 8.88+/-0.07 in the dimer-dimer interactions. Duck lens delta2-crystallin thus possesses a double dimer structure (alpha2)2 with stronger monomer-monomer interactions than the dimer-dimer interactions. The acidic protein solution's reneutralization caused rapid reassociation of monomers into dimers and tetramers. The tetramer-dimer monomer dissociation-reassociation thus is a pH-dependent freely interconvertible process. PMID- 9367646 TI - Cell-cell adhesion molecules and the development of an epithelial phenotype in cultured human retinal pigment epithelial cells. AB - For most epithelial cells, the adherens junction protein E-cadherin is an epithelial morphogen, inducing the development of an epithelial phenotype in vitro after cell contact at confluency. Here retinal pigment epithelial cells (RPE), which lack E-cadherin but express a cadherin that is also found in many non-epithelial cells (N-cadherin), were examined for the ability to produce an epithelial phenotype in vitro. Subpopulations of grossly epithelioid or fusiform cells were selected for analysis from RPE cultures derived from adult human donors. After confluency, epithelioid RPE cells were observed to undergo time dependent changes that were similar to those previously found in epithelial cells expressing E-cadherin: the cadherin gradually developed a zonular distribution of detergent-resistant protein that co-localized with forming circumferential actin bundles; Na/K ATPase accumulated at cell contact sites, then polarized to its tissue-specific domain (the apical membrane for RPE); the cells formed elevated domes on the impermeant culture substrate. In contrast to cells expressing E cadherin, these events in RPE required weeks rater than days at confluency. Additional proteins were examined in epithelioid RPE cells revealing that cytokeratins reorganized after confluency producing a zonular array, and several other adhesion proteins (alpha5beta1 integrin, ICAM-1, PECAM-1, NCAM) became enriched at cell-cell contact sites, each developing a distinct pattern at a distinct postconfluency interval. In contrast to epithelioid RPE, in fusiform RPE the adhesion molecules did not develop discrete distribution patterns after confluency, although the same complement of adhesion proteins was expressed. In cells expressing E-cadherin, the absence of epithelial properties is often due to underexpression of the cadherin or of the catenins, adherens junction proteins that link the cadherin to actin. Fusiform RPE, however, were not deficient in these proteins, expressing amounts of N-cadherin, alpha-catenin, beta-catenin, plakoglobin, p120, alpha-actinin and vinculin that were equivalent to epithelioid cells. It appears, therefore, that a subset of epithelial cells that express N cadherin can produce a highly-developed epithelial phenotype in vitro through a slow morphogenetic process. However, the expression alone of adhesion molecules, including those with a morphoregulatory function in other cells, is insufficient to produce an epithelial phenotype in all cells derived from the pigment epithelium. PMID- 9367647 TI - In vivo modification of the C-terminal lysine of human lens alphaB-crystallin. AB - Both the structural and chaperone-like properties of lens alpha-crystallins have been implicated in maintaining lens transparency. Modifications of lens alpha crystallins may lead to formation of cataract by affecting the close-packing of the crystallins or by reducing the chaperone-like activity of the alpha crystallins. A previously unreported modified alphaB-crystallin, whose molecular weight is 72 u greater than unmodified alphaB-crystallin, has been isolated from human lenses by size exclusion chromatography, reversed phase HPLC and ion exchange HPLC. Approximately one nanomole of this modified alphaB-crystallin was obtained from each of five human eye lenses. Molecular weight determinations of peptides produced by digestion with trypsin or endoproteinase Asp-N showed that the modification is in the C-terminal region of alphaB-crystallin. The fragmentation pattern of peptides from the C-terminal region, analysed by tandem mass spectrometry, located the modification of the epsilon-amino group of the C terminal lysine. The elemental composition of this modification, determined from its exact mass, is C3H4O2. Because this modification decreases the net charge of alphaB-crystallin by one unit, and because the C-terminus has been implicated in the chaperone activity attributed to alphaB-crystallin, this modification at Lys 175 may have a significant role in cataractogenesis. PMID- 9367648 TI - Spatiotemporal distribution of SPARC/osteonectin in developing and mature chicken retina. AB - Expression of SPARC (Secreted Protein, Acidic, Rich in Cysteine), a counteradhesive, calcium-binding extracellular matrix (ECM) glycoprotein, is associated with several morphogenetic events during early development. In this study, changes in the spatiotemporal distribution of SPARC transcripts and the protein during chicken retinal development were documented by in situ hybridization and indirect immunofluorescence microscopy. SPARC transcripts were first detected within the proliferating neural ectoderm at embryonic day 4. 5 (E4.5), followed short thereafter (E5) by appearance of SPARC. SPARC was enriched within the inner plexiform layer (IPL) by E10 and within the outer plexiform layer (OPL) by E14, several days after these layers became morphologically distinct. Significant levels of SPARC transcripts were first observed within the ganglion cell layer (GCL) at E17 prior to accumulation of SPARC within the nerve fiber layer, seen first at E20. SPARC protein was first detected within the developing retinal pigment epithelium (RPE) at E10 and increased significantly at RPE cells ceased to proliferate and continued differentiating. Of special note was the restriction of SPARC to the basal-half of the RPE cells. SPARC transcripts were similarly distributed in the adult retina, but at lower levels than in the period just prior to hatching. In the adult retina SPARC was retained in the nerve fiber layer and present in the inner nuclear layer (INL) and outer nuclear layer (ONL), but lost from the IPL and OPL. These changes in expression pattern with time indicate that SPARC is developmentally regulated and therefore may have important function(s) in both morphological development of the retina and functioning of the mature eye. PMID- 9367649 TI - Actin filament bundles in cortical fiber cells of the rat lens. AB - The distribution and organization of actin filament bundles were studied in cortical fiber cells of rat lenses at various ages (3 days to 2.5 months old), using thin-section electron microscopy, immunocytochemistry and immunoblotting. Electron microscopy showed that actin bundles were regularly found along cortical fiber cell membranes of the lens at all ages studied. The actin bundles were commonly arranged in three distinct units, one bundle in each fiber cell, located at the intersections where three hexagonal fiber cells meet as seen in cross sections. These actin bundles were approximately 150 nm in diameter and were composed of 7-nm small filaments. They were aligned parallel to the long axis of fiber cells as judged by both cross and longitudinal sections. The outside border of each bundle was always surrounded by a zone of 10-nm intermediate filaments which have the same orientation as that of the actin bundles. In longitudinal sections, elongated actin bundles were always parallel to the cell membranes. A number of individual actin bundles sometimes were found to form a chain with periodic short intervals. In addition, actin bundles were frequently associated with adherens junctions near the intersections and other regions of fiber cell membranes. By immunoelectron microscopy, we demonstrated that these filament bundles indeed contained actins. By rhodamine-phalloidin labelling, we found that labeled actin bundles appeared as large, distinct dots at the corners of hexagonal fiber cells in all ages studied. In addition, non-bundle F-actins were labeled preferentially along the cell membranes of the short sides of hexagonal fiber cells. This resulted in a unique zigzag pattern of actin labeling commonly seen in the cortical fiber cells of a mature rat lens. Finally, we showed that alpha-actinin was associated with the actin bundles in the fiber cells by immunofluorescent double labeling and immunoblotting. It is suggested that this unique arrangement of actin bundles in fiber cells may provide a stabilizing structure for forming a sharp angle at each corner of fiber cells, thereby the hexagonal shape of the cells can be maintained. PMID- 9367651 TI - The glycation of bovine lens betaL-, betaS- and gamma-crystallins demonstrated by isoelectric focusing and lectin staining. AB - The aim of the current study is to detect glycation of betaL-, betaS- and gamma crystallins in the young bovine lens. To determine which of the crystallins are glycated, we have made isoelectric focusing of the water-soluble crystallins of four bovine lenses of 1. 183+/-0.070 years. Samples are stained: (1) with Coomassie Brilliant Blue for proteins; (2) with the lectin Concanavalin-A, followed by horse-radish peroxidase (HRP) and diaminobenzidine (DAB). Experiments are performed with crystallins in native form, in absence of denaturants. The crystallins are separated by isoelectric focusing into: alpha-crystallins of high molecular weight (HM)-, alphaL-, betaH-, betaL-, betaS- and gamma-crystallins. In the lectin staining experiments only HM-, beta L-, betaS- and gamma-crystallins are positive, whereas the alphaL- and betaH-crystallins do not stain. Though glycation in the bovine lens is very low, lectin staining is sufficiently sensitive to detect the various glycated crystallins. PMID- 9367650 TI - Characterization of a potent uveitopathogenic site derived from rat phosducin. AB - Phosducin is a retinal and pineal phosphoprotein assumed to play an important role in visual phototransduction. Phosducin is also a uveitopathogenic retinal antigen, but its potency has been reported to be mild. During the course of studies aimed at identifying uveitopathogenic sites in phosducin, we found that rat phosducin possessed a potent uveitopathogenic site. In this study, we characterize the potent uveitopathogenic site by using synthetic peptides. Several synthetic peptides from this region plus adjuvants were injected into Lewis rats, and the uveitopathogenic core sequence was defined. We also determined the pivotal amino acid residues by using synthetic peptides with single residue substitution. Immunization with PDC(R)65-96 (amino acid residues 65 through 96 derived from rat phosducin) at doses of 0.83 nmol or more induced severe experimental autoimmune uveitis (EAU) in all rats within 12 days. Experimental autoimmune pinealitis (EAP) was also observed in all rats after immunization with 0.83 nmol or higher doses of the peptide. The lowest dose of the peptide to induce EAU and EAP was 0.24 nmol. The smallest peptide that induced EAU as severe as PDC(R)65-96 was PDC(R)77-87, which consisted of 11 amino acid residues (YELIHQDKEDE). The core sequence within the uveitopathogenic site was a pentapeptide (LIHQD), amino acid residues from 79 to 83. To determine the role of individual residues within PDC(R)77-87, we tested the uveitopathogenicity of analogues of PDC(R)75-85 and PDC(R)77-89, respectively, in which each of the residues from 77 to 87 was replaced by alanine (A). Analogous peptides bearing a single residue substitution at 80 (I-->A) and 82 (Q-->A), respectively, were not uveitopathogenic. Our findings demonstrated the presence of a potent uveitopathogenic site in PDC(R)65-96 whose potency in Lewis rats was comparable to that of S-antigen. The pivotal amino acid residues for uveitopathogenicity were the residues at 80 (I) and 82 (Q). The clinical and histological features of this EAU closely resembled those of the EAU induced by S-antigen and recoverin. PMID- 9367652 TI - Control of Drosophila retinoid and fatty acid binding glycoprotein expression by retinoids and retinoic acid: northern, western and immunocytochemical analyses. AB - In Drosophila, thorough retinoid deprivation is possible, optimizing investigation of the effects of vitamin A metabolites and retinoic acid on the visual system. Retinoids had been found to control transcription and translation of Drosophila's opsin gene. To follow this line of inquiry, we examined the effect of retinoids on the translation and transcription of a Drosophila Retinoid and Fatty Acid Binding Glycoprotein. Western blots showed that this protein is high in retinoid replete flies and low in deprived flies. Flies grown on media capable of activating the opsin gene's transcription and which contain alternate transcription activators including retinoic acid yielded extracts containing significant amounts of Retinoid and Fatty Acid Binding Glycoprotein. Immunocytochemistry confirmed its absence in deprived flies and its presence in flies reared or replaced on these diverse media containing retinoids or general nutrients. Immunocytochemistry localized Retinoid and Fatty Acid Binding Glycoprotein to the Semper (cone) cells and the intraommatidial matrix (the interphotoreceptor matrix of the ommatidium). Positive staining of Semper cells in mutants of the opsin gene and a mutant lacking receptors suggests that Retinoid and Fatty Acid Binding Glycoprotein does not depend on presence of opsin and that it is not synthesized in receptor cells respectively. Northern blots demonstrated greatly diminished mRNA for Retinoid and Fatty Acid Binding Glycoprotein in flies grown on deprivation food relative to flies grown on normal food. Although the synthesis of Retinoid and Fatty Acid Binding Glycoprotein does not require chromophore precursors as does that of opsin, the control of Retinoid and Fatty Acid Binding Glycoprotein and opsin transcription by retinoids including retinoic acid might very well be the same. Our results suggest that Retinoid and Fatty Acid Binding Glycoprotein may be involved in retinoid transport. Also, Semper cells may be analogous to vertebrate retinal pigment epithelium in retinoid metabolism and/or delivery. PMID- 9367653 TI - The genetics and biology of Phytophthora infestans: modern approaches to a historical challenge. AB - The oomyceteous fungus Phytophthora infestans, which causes the late blight diseases of potato and tomato, has a history that is closely associated with that of mycology and plant pathology. Nevertheless, P. infestans and other oomycetes remain poorly understood relative to fungi in other groups. A resurgence in the worldwide impact of late blight has recently increased interest in the species. Fortunately, over the past decade improved tools for laboratory analysis have been developed which provide an opportunity to advance our understanding of this important pathogen. Since oomycetes do not have a close taxonomic affinity with well-characterized organisms such as ascomycetes and basidiomycetes, it is likely that studies of P. infestans will yield novel biological findings. This review provides an update on the status of research into the fundamental aspects of the biology, genetics, and pathology of P. infestans and describes prospects for future advances. PMID- 9367654 TI - Expression of YWP1, a gene that encodes a specific Yarrowia lipolytica mycelial cell wall protein, in Saccharomyces cerevisiae. AB - The YWP1 gene encoding a specific mycelial cell wall protein of Yarrowia lipolytica has been cloned and expressed in Saccharomyces cerevisiae using different episomal plasmids. Because the plasmids pYAE35BB and pYAE35ES carrying the YWP1 gene (including the 5' noncoding promoter sequences) failed to express it, the YWP1 gene was cloned under the control of GAL/CYC or ACT S. cerevisiae promoters. A main band with an apparent molecular mass of 70 kDa was detected by immunoblotting in the cell wall fraction of transformants. Ywp1 processing and incorporation to the cell wall were similar in both Y. lipolytica and S. cerevisiae but not in its final localization in the cell wall. In Y. lipolytica Ywp1 is covalently bound to the cell wall (it is released only by Zymolyase digestion), whereas in S. cerevisiae it was not (it was released by boiling SDS solutions). These results suggest that the sequences involved in recognition, anchoring of a protein to the cell wall, or the catalytic activities implicated are different, at least for Ywp1, in Y. lipolytica and S. cerevisiae. Another possibility is that the target for attachment of Ywp1 is missing or cryptic in the cell wall of S. cerevisiae. PMID- 9367655 TI - Cloning and molecular characterization of CnTEF1 which encodes translation elongation factor 1alpha in Cryptococcus neoformans. AB - Degenerate PCR primers were synthesized based upon known translation factor 1alpha (TEF1) sequences. Touchdown PCR with these primers utilizing Cryptococcus neoformans strain M1-106 genomic DNA as template produced a DNA fragment containing a portion of CnTEF1. This DNA fragment was used as a hybridization probe to clone a cDNA version of CnTEF1 from C. neoformans strain B3501. Comparison of the genomic and cDNA nucleotide sequences revealed the presence of six introns in CnTEF1. The nucleotide sequence of CnTEF1 from these two strains of C. neoformans were 98% identical. Codon bias for most amino acids encoded by CnTEF1 was similar to that observed in Saccharomyces cerevisiae for highly expressed genes. This codon bias was also observed in the C. neoformans ACT gene. CnTEF1 encoded a protein (CnEF-1alpha) consisting of 459 amino acids with a calculated MW of 50.3 kDa from C. neoformans strain B3501. CnTEF1 from strain M1 106 encoded a protein with one additional aa. Both C. neoformans proteins possessed a high degree of identity throughout their length to fungal, human, and plant EF-1alpha proteins. PMID- 9367656 TI - Molecular characterization of mutants of the acetate regulatory gene facB of Aspergillus nidulans. AB - The facB gene of Aspergillus nidulans encodes a DNA binding transcriptional activator required for growth on acetate as a sole carbon source. FacB contains N terminal GAL4-like Zn(II)2Cys6 (or C6 zinc) binuclear cluster DNA binding and leucine zipper-like heptad repeat motifs and central and C-terminal acidic alpha helical regions. facB recessive loss of function mutants are deficient in acetate induction of acetyl-CoA synthase, isocitrate lyase, malate synthase, acetamidase, and NADP-isocitrate dehydrogenase. Characterization of lesions in facB mutant alleles has localized important functional regions of the FacB protein. Two extreme mutants are shown to lack the C-terminal region of the protein. Two temperature sensitive mutants contain amino acid substitutions in the DNA binding domain and are shown to affect acetate induction of amdS-lacZ expression and confer temperature sensitive in vitro DNA binding. Two temperature sensitive facB mutations result in thermolability of acetyl-CoA synthase, isocitrate lyase, and malate synthase but not acetamidase or NADP-isocitrate dehydrogenase in crude extracts. This suggests that FacB may have a structural role in acetate metabolism in addition to its regulatory function. PMID- 9367657 TI - Base composition of DNA from glomalean fungi: high amounts of methylated cytosine. AB - Glomales (Zygomycetes) are obligate fungal symbionts of roots of land plants and form arbuscular mycorrhiza. Sporal DNA of 10 isolates belonging to nine species was purified and the base composition was determined by RP-HPLC. Base composition fell in a narrow range between 30 and 35% G + C. A high amount of methylated cytosine (mC) accounting for 2-4% of the total nucleotides was found in all taxa. The DNA melting profile was defined for Scutellospora castanea. It corresponded to 32% G + C, and the shape of the denaturation curve suggested a heterogeneity in the GC content within the fungal genome. Knowledge of GC contents and variations between taxa are essential for evaluating nuclear DNA content using fluorimetric methods, and high proportions of mC/C + mC in the genomes of glomalean fungi could reflect the existence of repeated DNA families. Results are discussed in relation to data for other fungi and eukaryotes. PMID- 9367658 TI - Asexual sporulation in coprinus cinereus: structure and development of oidiophores and oidia in an amut bmut homokaryon AB - Polak, E., Hermann, R., Kues, U., and Aebi, M. 1997. Asexual sporulation in Coprinus cinereus: Structure and development of oidiophores and oidia in an Amut Bmut homokaryon. 22, 112-126. Coprinus cinereus strain AmutBmut is a homokaryon with mutations in both mating type loci. It produces asexual spores (oidia) in sticky liquid droplets on specialized aerial structures (oidiophores). These oidiophores have uninucleate cells and are organized as those of the monokaryon 5026 from which the strain derived. However, unlike in the monokaryon, oidiophores in strain AmutBmut are induced by light. Young oidiophores are easily detected upon light induction and the process of oidiophore development is readily followed in this strain. Fully grown oidiophores consecutively give rise to short branches (oidial hyphae) that break up into two or occasionally three uninucleate oidia (arthroconidia) until up to 200 oidia are collected at the tip of the oidiophore. Mature spores are enclosed by a mucilage and a double-layered primary cell wall with hair-like structures except for the sides of former cell attachments. In a summary of our microscopic observations on developing oidiophores and nuclear stainings we present a model showing the successive steps of oidiophore and spore development. PMID- 9367659 TI - Direct evidence for Ca2+ regulation of hyphal branch induction AB - Grinberg, A., and Heath, I. B. 1997. Direct evidence for Ca2+ regulation of hyphal branch induction. 22, 127-139. Irradiation of growing hyphae of Saprolegnia ferax with microbeams of UV (300-380 and 385-450 nm) light induced an increase in cytoplasmic [Ca2+] followed by precocious formation of one or more branches within about 4 min. The distribution of branches was strongly skewed toward the subapical side of the irradiation site, but otherwise was apparantly random. Apical (10-&mgr;m) irradiations were more effective than subapical (50 &mgr;m) ones in that they induced branches at comparable frequencies but with lower doses, consistent with higher concentrations of putative target intracellular Ca2+ storage structures in this region. Once formed, induced adjacent branches seem to compete for "resources," with those closer than approximately 50 &mgr;m inhibiting each other. The results are most consistent with Ca2+-induced accumulation of branch initiating factors being the cause, not the consequence, of branch formation, thus supporting a primary role for Ca2+ in regulation of hyphal tip growth. Copyright 1997 Academic Press. Copyright 1997 Academic Press PMID- 9367660 TI - Antisense oligonucleotides as therapeutic agents. AB - The potential for modulating gene expression by the use of antisense oligonucleotides has become increasingly interesting in recent years. Antisense oligonucleotides are complementary nucleic acid fragments that hybridize to target sequences within RNA to form a DNA-RNA duplex, resulting in the block of translation of messenger RNA into the protein. Advances in chemistry and molecular biology have provided the basis to develop antisense oligodeoxynucleotides and improve their selectivity, stability and specificity of action. The antisense technology has been extensively used in vitro and in vivo as a tool to study the regulatory mechanisms in biologic processes and as potential therapeutic agents in cancer, viral infections and genetic disorders. In the present review, the various approaches for the use of antisense molecules in oncology, virology, genetic and inflammatory diseases are described; several studies, supporting the in vitro and in vivo applications of this technology, are also presented. Moreover, the potential clinical use of antisense therapies is discussed. PMID- 9367661 TI - Involvement of alpha2-adrenergic mechanisms in experimental analgesic and anti inflammatory activities of a benzamide derivative. AB - Several non-steroidal anti-inflammatory drugs of the N-pyridinyl-benzamide series that produce experimental peripheral and central anti-inflammatory effects possess a dopaminomimetic component and inhibit eicosanoid synthesis without acting directly on the enzymes classically involved in this process. We compared the anti-inflammatory and analgesic activities of one of the most active benzamide derivatives with those of clonidine. Rat paw and brain edemas were inhibited by these two agents, whereas different methods showed that yohimbine counteracted this effect and the analgesia it induced. The involvement of an alpha2-adrenergic and/or serotoninergic components in these activities is considered, without excluding the possibility that the mechanism of action is in part due to inhibition of prostaglandin synthesis. PMID- 9367662 TI - Modulating effect of Semecarpus anacardium Linn. nut extract on glucose metabolizing enzymes in aflatoxin B1-induced experimental hepatocellular carcinoma. AB - The herbal remedy extended by Semecarpus anacardium nut extract against Aflatoxin B1 mediated hepatocellular carcinoma was established by studies on carbohydrate metabolizing enzymes. Since some definite correlation exists between tumour progression and the activities of glycolytic and gluconeogenic enzymes, assessment of alterations in their activity can be used as successful markers of diagnosis and prognosis. The present work compares the activities of glycolytic and gluconeogenic enzymes in hepatocellular carcinoma bearing rats with drug treated animals. An overall increase in glycolytic enzymes namely hexokinase, phosphoglucoisomerase, and aldolase with a subsequent reduction in gluconeogenic enzymes, glucose-6-phosphatase and fructose-1,6-biphosphatase was observed in plasma and liver homogenates of hepatocellular carcinoma bearing rats. The administration of Semecarpus anacardium nut extract caused a significant decrease in the activity of glycolytic enzymes and an increase in gluconeogenic enzymes' activities to near normal values in drug-treated animals. PMID- 9367663 TI - Antifungal, antibacterial, antiviral and cytotoxic activity of novel thio- and seleno-azoles. AB - A series of pentaatomic heterocyclic compounds containing sulphur or selenium in position 2, were tested for cytotoxicity, antiviral and antimicrobial activities. Generally, selenium-containing compounds were more toxic than the corresponding sulphur-containing ones (30-75 times more toxic) and, furthermore, the biological activity against some microorganisms was also enhanced. In particular, some selenium-containing derivatives exerted an inhibitory activity on plant pathogenic fungi at doses markedly lower than the toxic ones, showing an interesting selectivity of action. In this case the tested compounds appeared more active than ketoconazole, the control used, with an almost comparable degree of cytotoxicity. PMID- 9367664 TI - Effect of atrazine administration on spontaneous and evoked cerebellar activity in the rat. AB - The effect of atrazine oral administration on cerebellar forelimb projection area was studied in rats in vivo. Rats acutely treated with atrazine (100 mg kg-1, BW) showed a significant decrease in spontaneous Purkinje cell firing rate. Atrazine also decreased the cerebellar potentials evoked by electrical stimulation of the ipsilateral radial nerve, affecting mostly the response to climbing fiber input. These results demonstrate that atrazine exerts a toxic action on central nervous system. The effects on the cerebellar somatosensory cortex could be responsible for motor disorders frequently observed in animals intoxicated with atrazine. PMID- 9367665 TI - Effects of competitive and non-competitive NMDA receptor antagonists on behavioral responses induced by 7-OH-DPAT and quinpirole in rats. AB - The administration of dizocilpine (0.06 mg kg-1), but not of CGP 43487 (0.75 mg kg-1), counteracted the hypolocomotion induced in the rat by low doses (5-80 microg kg-1) of the putative D3 dopamine agonist 7-OH-DPAT. Both NMDA antagonists did not change the reduced locomotion due to the administration of low doses (12.5-50 microg kg-1) of the D2 agonist quinpirole. In spite of the lack of effect of either NMDA receptor antagonist on D2 or D3 recognition sites, as shown by our radioligand binding studies, the behavioural findings suggest that the non competitive, but not the competitive, NMDA receptor antagonist physiologically antagonizes dopamine D3 receptor mediated mechanisms. Both NMDA receptor antagonists failed to modify the hyperlocomotion induced by high doses (160 and 320 microg kg-1) of 7-OH-DPAT, whereas they inhibited the same behavioural response produced by high doses of quinpirole (150 and 300 microg kg-1). The different effect of the NMDA receptor antagonists on the behavioural responses induced by the dopaminergic agonists could be explained by the different activity of 7-OH-DPAT and quinpirole on D3/D2 receptors. Either dizocilpine or CGP 43487 induced stereotyped responses to high doses of 7-OH-DPAT. This suggests that both NMDA receptor antagonists could potentiate dopaminergic function in the striatum, a region critically involved in the generation of stereotyped behaviour. PMID- 9367666 TI - The cooperation between the influx of extracellular calcium and alpha1 adrenoceptor-induced translocation of protein kinase C. AB - Calcium ionophore A23187 or phenylephrine injected i.p. in doses of 0.05-0 .25 mg kg-1 and 0.1-1 mg kg-1, respectively, induced translocation of protein kinase C (PKC) from the cytosol to the membrane fraction of the rat frontal cortex and hippocampus. The action of A23187 was blocked in a dose-dependent manner by nifedipine and verapamil. The phenylephrine induced translocation of PKC was blocked by prazosin and in a dose-dependent manner by nifedipine and verapamil. In contrast, pre-treatment with a small, ineffective by itself, dose of A23187 (0.02 mg kg-1) potentiated the alpha1-adrenoceptor induced translocation of PKC. Thus, it seems that the influx of calcium ions through an L-type calcium channel is probably necessary for a full alpha1-adrenoceptor mediated activation and translocation of PKC. PMID- 9367667 TI - Action of capparis decidua against alloxan-induced oxidative stress and diabetes in rat tissues. AB - Alloxan-induced diabetic rats were treated with insulin (i.p.) or with Capparis decidua powder as a hypoglycaemic agent mixed with diet. The effect was assessed on lipid peroxidation (LPO) and the antioxidant defense system in rat tissues. The increased levels of blood glucose in diabetes produce superoxide anions and hydroxyl radicals in the presence of transition metal ions which cause oxidative damage to cell membranes. The heart tissue showed an increased lipid peroxidation (LPO) in diabetic rats while no significant change was observed in the liver and kidney. The treatment with C. decidua lowered LPO in these tissues even more effectively than insulin-treated rats. The superoxide dismutase (SOD) activity increased in the heart and kidneys in the diabetic group of rats probably to increase dismutation of superoxide anions. However, treatment with C. decidua decreased SOD activity in the liver and kidney and was comparable to control rats. Catalase (CAT) activity was not significantly affected in any of the tissues in diabetic and insulin-treated animals, however, CAT activity markedly increased in tissues with C. decidua treatment. Total and Se-dependent glutathione peroxidase (GSH-Px) in the heart was markedly lowered in diabetic rats which recovered with insulin as well as with C. decidua treatment. The increase in GSH-Px and CAT activity with C. decidua treatment may lower H2O2 toxicity and reduce oxidative stress in diabetes. However, glutathione (GSH) content in the heart and kidney and glutathione reductase (GSH-R) activity in all the tissues studied increased in diabetic rats while treatment with insulin lowered GSH content and GSH-R activity in these tissues. The treatment with C. decidua also decreased GSH-R activity in the kidney and heart which resulted in the decrease in GSH content in these tissues. The changes such as the increase in kidney and heart SOD may be an adaptive response in order to neutralize superoxide anions. The increase in GSH content and GSH-R activity in the tissue are in response to neutralize superoxide anions and to counteract oxidative stress in diabetes. Glutathione S-transferase (GST) was not significantly affected in diabetic rat tissue, however, heart GST increased with antidiabetic treatments. The increase in glucose-6-phosphate dehydrogenase (G6PDH) in the kidney and heart of diabetic rats subsequently decreased with C. decidua treatment. The increase in G6PDH in tissues may increase NADPH generation required for GSH-R activity and GSH production. It is suggested that these changes initially counteract the oxidative stress in diabetes, however, a gradual decrease in the antioxidative process may be one of the factors which results in chronic diabetes. The data indicate that C. decidua may have potential use as an antidiabetic agent and in lowering oxidative stress in diabetes. PMID- 9367668 TI - A comparative study on biochemical markers of bone collagen breakdown in post menopausal women. AB - The aim of this study was to compare urinary galactosylhydroxylysine (GHyl) and deoxypyridinoline (d-Pyr) as biochemical markers of bone resorption in post menopausal women treated and untreated with estrogen and cyclic etidronate. Fasting urinary GHyl, D-Pyr, pyridinoline, serum osteocalcin and total alkaline phosphatase were measured in three subgroups, i.e. post-menopausal women undergoing hormone replacement therapy, untreated post-menopausal women and post menopausal women with low BMD treated with disodium etidronate. The results indicated that GHyl did not significantly discriminate between untreated post menopausal women and estrogen replated ones unless an osteoporotic untreated group was selected. d-Pyr and GHyl showed similar performances when their values after bisphosphonate treatment were compared to those found in untreated post menopausal women, thus suggesting that both markers were equal in their ability to detect the bone response to cyclic etidronate administration. This observation further proves the statement that GHyl is prone to confounding factors under estrogen therapy but it is adequate as is d-Pyr in monitoring the bone response to bisphosphonate treatment. PMID- 9367669 TI - Vasodilating effects of tetrazepam in isolated vascular smooth muscles: comparison with cromakalim and diltiazem. AB - The vasodilating effects of tetrazepam (1,4-benzodiazepine derivative) were studied and compared with those of the K-channel activator, cromakalim and the Ca channel blocker, diltiazem, in rat aorta smooth muscle and on the spontaneous contractile activity of the rat portal vein. In the aorta, tetrazepam (3 x 10(-7) 10(-4) M) and diltiazem (10(-8)-3 x 10(-6) M) concentration-dependently relaxed aortic rings contracted by 30 mM as well as 80 m KCl. Although cromakalim (10(-8) 3 x 10(-6) M) concentration-dependently relaxed aortic rings contracted by 30 mM KCl, it did not relax those contrated by 80 mm KCl. In the presence of the ATP sensitive K-channel blocker, glibenclamide (10(-6) and 3 x 10(-6) M), 30 mM KCl concentration-response curves for the relaxant effect of tetrazepam and diltiazem were unaffected but cromakalim caused a progressive shift of these curves upwards. In the portal vein, tetrazepam inhibited spontaneous contractions, decreased amplitude and increased frequency. Similar behaviour was shown with diltiazem (10(-8)-10(-5) M) and in both cases, pre-treatment with glibenclamide (10(-6) M) was ineffective. Although cromakalim (10(-5)-10(-6) M) decreased both amplitude and frequency, this effect was blocked by glibenclamide. These results indicate that the vasodilator action of tetrazepam is not mediated to the opening of ATP-sensitive K-channels, unlike cromakalim. This may be mediated, like those of diltiazem, by the blockade of calcium movements across the cell membrane. PMID- 9367670 TI - Evidence for oxidative stress in the hepatic mitochondria of bile duct ligated rats. AB - Lipid peroxidation increased both in the liver homogenates and in the hepatic mitochondrial fraction of bile duct ligated (BDL)-rats. Although mitochondrial superoxide dismutase (SOD) activity did not change in the liver, glutathione (GSH) levels and glutathione peroxidase (GSH-Px) activity decreased in hepatic mitochondrial fraction of BDL-rats as compared to sham-operated rats. In addition, GSH-Px and glutathione transferase (GST) activities decreased but SOD activity remained unchanged in the post-mitochondrial fraction of the liver from BDL-rats. However, erythrocyte lipid peroxide and GSH levels did not change in BDL-rats. In conclusion, our results show that the disturbance of oxidant antioxidant balance especially in mitochondria may be responsible for cholestatic liver injury in BDL-rats. PMID- 9367671 TI - 'In vitro' interactions of monensin with hepatic xenobiotic metabolizing enzymes. AB - Monensin, a polyether ionophore antibiotic used worldwide for its anticoccidial and growth-promoting properties, is reported to act as anin vivo inducer or inhibitor of drug-metabolizing enzyme systems in various species according to dosage regimens and duration of exposure. When incubated at a concentration up to 0.25 mM with hepatic subfractions from either untreated- (UT) or phenobarbital- (PB) induced rats, monensin did not induce appreciable changes in cytochrome P450 content and functions as well as in NADPH cytochrome c reductase or glutathione S transferase. On the other hand, monensin concentrations ranging from 0.05 to 0.25 mM proved to increase the initial rate of NADPH oxidation up to 63% in UT microsomes, and the in vitro addition of the ionophore to microsomes resulted in the formation of a characteristic type I binding spectrum. The rate of monensin O demethylation was 0.34+/-0. 01 and 0.99+/-0.07 nmol min-1 per mg of protein in UT and PB-microsomes, respectively. In the latter, this reaction was consistently depressed when NADPH was omitted or replaced with NADH, or upon the addition of 1 mM metyrapone, a known P450 inhibitor. It is concluded that monensin does not behave as a direct in vitro inhibitor of drug metabolizing enzymes and appears to be a substrate of P450-dependent monooxygenases. PMID- 9367672 TI - High-resolution physical map of the immunoglobulin lambda variant gene cluster assembled by quantitative DNA fiber mapping. AB - Quantitative DNA fiber mapping (QDFM) allows rapid construction of near-kilobase resolution physical maps by hybridizing specific probes to individual stretched DNA molecules. We evaluated the utility of QDFM for the large-scale physical mapping of a rather unstable, repeat-rich 850-kb region encompassing the immunoglobulin lambda variant (IGLV) gene segments. We mapped a minimal tiling path composed of 32 cosmid clones to three partially overlapping yeast artificial chromosome (YAC) clones and determined the physical size of each clone, the extent of overlap between clones, and contig orientation, as well as the sizes of gaps between adjacent contigs. Regions of germline DNA for which we had no YAC coverage were characterized by cosmid to cosmid hybridizations. Compared to other methods commonly used for physical map assembly, QDFM is a rapid, versatile technique delivering unambiguous data necessary for map closure and preparation of sequence-ready minimal tiling paths. PMID- 9367673 TI - The human extracellular matrix gene 1 (ECM1): genomic structure, cDNA cloning, expression pattern, and chromosomal localization. AB - The Ecm1 gene encodes an 85-kDa protein of unknown function that was originally identified as a secretory protein of the murine osteogenic stromal cell line MN7. This paper describes the isolation of a genomic clone containing the human ECM1 gene from a chromosome 1 cosmid library and the characterization of its exon intron structure. The protein coding region comprises 10 exons. The ECM1 gene maps at chromosome 1q21 outside the epidermal differentiation complex region. The ECM1 gene appears to be expressed as a 1.8-kb transcript predominantly in placenta and heart, while an additional 1.4-kb alternatively spliced message was detected in tonsils. The full-length human ECM1 transcript contains 1838 bp and has an overall homology of 79.6% with the mouse Ecm1 cDNA. This transcript codes for a protein of 540 amino acids that is 69.4% identical and 81.3% similar to the corresponding mouse protein. The alternatively spliced variant, 1450 bp long, encodes a protein of 415 amino acids. PMID- 9367674 TI - Structural organization of the mouse and human GALR1 galanin receptor genes (Galnr and GALNR) and chromosomal localization of the mouse gene. AB - The neuropeptide galanin elicits a range of biological effects by interaction with specific G-protein-coupled receptors. Human and rat GALR1 galanin receptor cDNA clones have previously been isolated using expression cloning. We have used the human GALR1 cDNA in hybridization screening to isolate the gene encoding GALR1 in both human (GALNR) and mouse (Galnr). The gene spans approximately 15-20 kb in both species; its structural organization is conserved and is unique among G-protein-coupled receptors. The coding sequence is contained on three exons, with exon 1 encoding the N-terminal end of the receptor and the first five transmembrane domains. Exon 2 encodes the third intracellular loop, while exon 3 encodes the remainder of the receptor, from transmembrane domain 6 to the C terminus of the receptor protein. The mouse and human GALR1 receptor proteins are 348 and 349 amino acids long, respectively, and display 93% identity at the amino acid level. The mouse Galnr gene has been localized to Chromosome 18E4, homoeologous with the previously reported localization of the human GALNR gene to 18q23 in the same syntenic group as the genes encoding nuclear factor of activated T-cells, cytoplasmic 1, and myelin basic protein. PMID- 9367675 TI - Structural characterization of the mouse Hfh4 gene, a developmentally regulated forkhead family member. AB - Hepatocyte nuclear factor-3/forkhead homologue 4 (HFH-4) is a forkhead/winged helix transcription factor family member that has a unique temporal and spatial pattern of gene expression in the developing and adult lung, choroid plexus, testis, and oviduct. To characterize HFH-4 further, mouse genomic clones were isolated and analyzed. The Hfh4 gene is encoded on a 5.5-kb region located on the distal end of mouse chromosome 11 and consists of two exons and one intron. Unlike most forkhead genes, the DNA binding domain is divided between two exons, and the intron position corresponds precisely to the site of gene translocations involving two known human forkhead homologues. Multiple putative transcription start sites are identified in a G+C-rich sequence that does not contain TATA or CAAT boxes. Within 2.1 kb of 5' flanking sequence are three identical E boxes and multiple putative transcription factor binding sites. Transfection of plasmids containing Hfh4 5' flanking sequence linked to a reporter gene results in promoter activity in lung epithelial cells but not in epithelial-like fibrosarcoma cells, suggesting that this 5' flanking sequence can function as a promoter with the proper cell-type specificity. PMID- 9367676 TI - Genomic organization, chromosomal localization, and expression of the murine thromboxane synthase gene. AB - Thromboxane synthase (TS) is a membrane-bound cytochrome P450 enzyme catalyzing the synthesis of TxA2, a potent modulator of vascular smooth muscle contraction and platelet aggregation. TS plays an important role in hemostasis and may be intimately involved in the etiology of cardiovascular, renal, and immune diseases. Restriction enzyme mapping, subcloning, and DNA sequencing analysis of recombinant phage lambda and P1 clones revealed that exons encoding the 1.9-kb mouse TS mRNA are dispersed over >150 kb genomic DNA. Determination of the intron exon splicing junctions established that the mouse TS gene (Tbxas1) is encoded by 13 exons ranging in size from 53 (exon III) to 315 bp (exon IX). Genomic Southern analysis and fluorescence in situ hybridization suggested that the gene is a single-copy gene, located on chromosome 6 near the midpoint between the centromere and the Igkappa gene. An alternatively spliced variant of the Tbxas1 transcript, lacking the exon XII-encoded sequence, has been detected in normal mouse tissues. Ribonuclease protection and 5'-RACE assays identified at least five major transcription start sites clustered within 31 bp of the Tbxas1 promoter. The 5'-most start site is not preceded by a TATA box, suggesting transcription can be initiated in a TATA-independent manner. Transfection analyses indicated that the expression of Tbxas1 is controlled by a short (70-bp) positive regulatory sequence and several upstream repressive elements. Mutational studies further demonstrated that NF-E2/AP-1 and Sp1 exerted activating and repressive, respectively, effects on the promoter. These studies provide the genetic tools and information for TS research in mice, which should expedite understanding of the genetic contribution of TS in normal physiology as well as in disease states. PMID- 9367677 TI - Identification and characterization of BRDT: A testis-specific gene related to the bromodomain genes RING3 and Drosophila fsh. AB - The RING3 gene encodes a 90-kDa mitogen-activated nuclear protein. In proliferating cells, including in leukemia, RING3 has serine-threonine kinase and autophosphorylation activities. The cloning of D26362, a gene closely related to RING3, suggests a gene family. RING3 and D26362 are also related to the Drosophila developmental gene fsh. A database search for further members of the RING3 family identified an EST derived from a testis-specific library. cDNA clones representing the full coding sequence of the gene were isolated. The gene encodes a protein of 947 amino acids with extensive homology to RING3, D26362, and fsh. Similar to these proteins, it possesses two bromodomain motifs and a PEST sequence. Northern analysis of 16 normal tissues and eight cancer cell lines shows transcripts of 3.5 and 4.0 kb expressed specifically in testis. The gene has been named BRDT (for bromodomain, testis specific). PCR analysis of a panel of monochromosomal human/rodent hybrid cell lines and the GeneBridge 4 panel of radiation hybrids localizes the gene to chromosome 1p between markers WI-7719 and WI-3099 (D1S2154). PMID- 9367678 TI - Genome organization of human 48-kDa oligosaccharyltransferase (DDOST). AB - The enzyme oligosaccharyltransferase (dolichyl-diphosphooligosaccharide-protein glycosyltransferase; EC 2. 4.1.119) (DDOST) catalyzes the transfer of a high mannose oligosaccharide (GlcNac2Man9Glc3) from a dolichol-linked oligosaccharide donor (dolichol-P-GlcNac2Man9Glc3) onto the asparagine acceptor site within an Asn-X-Ser/Thr consensus motif in nascent polypeptide chains across the membrane of the endoplasmic reticulum. We isolated mouse and human DDOST cDNAs from retinoic acid-treated mouse P19 EC cells and human NT-2 cells, respectively. DDOST mRNA is expressed intensely in heart and pancreas, but at lower levels in brain. Here we show that the human DDOST 48-kDa subunit gene (HGMW-approved symbol DDOST) is organized into 11 exons expanding about 9 kb. This DDOST subunit gene is localized on chromosome 1p36.1 by fluorescence in situ hybridization analysis. PMID- 9367679 TI - Characterization of the gene encoding human sarcolipin (SLN), a proteolipid associated with SERCA1: absence of structural mutations in five patients with Brody disease. AB - Sarcolipin (SLN) is a low-molecular-weight protein that copurifies with the fast twitch skeletal muscle sarcoplasmic reticulum Ca2+ ATPase (SERCA1). Genomic DNA and cDNA encoding human sarcolipin (SLN) were isolated and characterized and the SLN gene was mapped to chromosome 11q22-q23. Human, rabbit, and mouse cDNAs encode a protein of 31 amino acids. Homology of SLN with phospholamban (PLN) suggests that the first 7 hydrophilic amino acids are cytoplasmic, the next 19 hydrophobic amino acids form a single transmembrane helix, and the last 5 hydrophilic amino acids are lumenal. The cytoplasmic and transmembrane sequences are not well conserved among the three species, but the lumenal sequence is highly conserved. Like SERCA1, SLN is highly expressed in rabbit fast-twitch skeletal muscle, but it is expressed to a lower extent in slow-twitch muscle and to an even lower extent in cardiac muscle, where SERCA2a and PLN are highly expressed. It is expressed in only trace amounts in pancreas and prostate. SLN and PLN genes resemble each other in having two small exons, with their entire coding sequences lying in exon 2 and a large intron separating the two segments. Brody disease is an inherited disorder of skeletal muscle function, characterized by exercise-induced impairment of muscle relaxation. Mutations in the ATP2A1 gene encoding SERCA1 have been associated with the autosomal recessive inheritance of Brody disease in three families, but not with autosomal dominant inheritance of the disease. A search for mutations in the SLN gene in five Brody families, four of which were not linked to ATP2A1, did not reveal any alterations in coding, splice junction or promoter sequences. The homozygous deletion of C438 in the coding sequence of ATP2A1 in Brody disease family 3, leading to a frameshift and truncation following Pro147 in SERCA1, is the fourth ATP2A1 mutation to be associated with autosomal recessive Brody disease. PMID- 9367680 TI - Amplification of CFTR exon 9 sequences to multiple locations in the human genome. AB - Cloning and characterization of the cystic fibrosis transmembrane conductance regulator (CFTR) gene led to the identification and isolation of cDNA and genomic sequences that cross-hybridized to the first nucleotide binding fold of CFTR. DNA sequence analysis of these clones showed that the cross-hybridizing sequences corresponded to CFTR exon 9 and its flanking introns, juxtapositioned with two segments of LINE1 sequences. The CFTR sequence appeared to have been transcribed from the opposite direction of the gene, reversely transcribed, and co-integrated with the L1 sequences into a chromosome location distinct from that of the CFTR locus. Based on hybridization intensity and complexity of the restriction fragments, it was estimated that there were at least 10 copies of the "amplified" CFTR exon 9 sequences in the human genome. Furthermore, when DNA segments adjacent to the insertion site were used in genomic DNA blot hybridization analysis, multiple copies were also detected. The overall similarity between these CFTR exon 9-related sequences suggested that they were derived from a single retrotransposition event and subsequent sequence amplification. The amplification unit appeared to be greater than 30 kb. Physical mapping studies including in situ hybridization to human metaphase chromosomes showed that multiple copies of these amplified sequences (with and without the CFTR exon 9 insertion) were dispersed throughout the genome. These findings provide insight into the structure and evolution of the human genome. PMID- 9367681 TI - Physical characterization of the chromosomal rearrangements that accompany the transgene insertion in the chakragati mouse mutant. AB - The circling phenotype of the chakragati mouse is a result of a transgenic insertional mutation. The absence of the phenotype in mice heterozygous for the transgene insertion suggests that this is due to a loss of function of an endogenous gene. Efforts to identify this gene have led to a previous report that sequences flanking the transgene, D16Ros1 and D16Ros2, map 10 cM apart in wildtype mice. We present here physical mapping data indicating that the proximity of D16Ros1 and D16Ros2 in the ckr mouse is explained by a duplication of D16Ros2 and its insertion along with the transgene at D16Ros1. We further demonstrate that D16Ros1 sequences are also duplicated and that this duplication is also part of the insertion at the endogenous D16Ros1 locus. PMID- 9367682 TI - Genetic characterization of the chromosomal rearrangements that accompany the transgene insertion in the chakragati mouse mutant. AB - We have previously reported that the circling phenotype of the chakragati mouse segregates with the transgene integration event as an autosomal recessive trait. It was unclear, however, whether the phenotype was linked to the transgene integration point near D16Ros1 or to a potential disruption at D16Ros2, 10 cM away. We report here that animals recombinant between D16Ros1 and D16Ros2, homozygous for the transgene insertion at D16Ros1, but wildtype for D16Ros2, do indeed show the phenotype. We conclude that any potential disruption at the D16Ros2 locus is not responsible for the circling phenotype. We further show that recombination between D16Ros1 and D16Ros2 occurs at a greatly reduced level in the chakragati mouse compared to wildtype strains. Detailed genetic analysis of recombinants indicates that the proximal-most 4.5 cM shows no recombination in over 1400 meioses. We propose that this is due to an inversion in this region, and we genetically define the proposed distal inversion break point to a 1.3-cM region between D16Mit63 and D16Mit169. PMID- 9367683 TI - Relationship between the genomic organization and the overlapping embryonic expression patterns of the zebrafish dlx genes. AB - To understand the relationship between the expression and the genomic organization of the zebrafish dlx genes, we have determined the genomic structure of the dlx2 and dlx4 loci. This led to the identification of the zebrafish dlx1 and dlx6 genes, which are closely linked to dlx2 and dlx4, respectively. Therefore, the inverted convergent configuration of Dlx genes is conserved among vertebrates. Analysis of the expression patterns of dlx1 and dlx6 showed striking similarities to those of dlx2 and dlx4, respectively, the genes to which they are linked. Furthermore, the expression patterns of dlx3 and dlx7, which likely constitute a third pair of convergently transcribed genes, are indistinguishable. Thus, the overlapping expression patterns of linked Dlx genes during embryonic development suggest that they share cis-acting sequences that control their spatiotemporal expression. The evolutionary conservation of the genomic organization and combinatorial expression of Dlx genes in distantly related vertebrates suggest tight control mechanisms that are essential for their function during development. PMID- 9367684 TI - Complex expression pattern of the TNF region gene LST1 through differential regulation, initiation, and alternative splicing. AB - Recently, a novel gene, LST1, was identified in the tumor necrosis factor region of the HLA complex, 4 kb centromeric of the lymphotoxin beta gene. By analyzing several full-length cDNA clones and the genomic DNA, we identified seven exons and four introns, spanning 2.7 kb. Isolation of mouse LST1 cDNA clones established the open reading frame. LST1 transcription is characterized by four alternative transcription initiation sites and extensive alternative splicing. The derived polypeptides vary with regard to the presence of the hydrophobic N terminus and in short internal sequences. In addition, alternative splicing results in LST1 mRNAs encoding different carboxy-terminal sequences. LST1 is predominantly transcribed in monocytes, and mRNA levels increase upon stimulation with interferon-gamma, with a concomitant change in the mRNA pattern resulting in an enhanced expression of the short LST1 transcripts. These data suggest that LST1 may have a specific role in monocytes and possibly also in T cells. Moreover, we found that the recently published cDNA 1C7 is encoded just centromeric of LST1. PMID- 9367685 TI - A human homologue (BICD1) of the Drosophila bicaudal-D gene. AB - We previously isolated a cDNA fragment homologous to the Drosophila Bicaudal-D gene (Bic-D) using a hybridization selection procedure with cosmids derived from the short arm of human chromosome 12. A PCR-mediated cDNA cloning strategy was applied to obtain the coding sequence of the human homologue (BICD1) and to generate a partial mouse (Bicdh1) cDNA. The Drosophila Bicaudal-D gene encodes a coiled coil protein, characterized by five alpha-helix domains and a leucine zipper motif, that forms part of the cytoskeleton and mediates the correct sorting of mRNAs for oocyte- and axis-determining factors during oogenesis. Analysis of the predicted amino acid sequence of the BICD1 cDNA clones indicates that the sequence similarity is essentially limited to the amphipatic helices and the leucine zipper, but the conserved order of these domains suggests a similar function of the protein in mammalians. A database search further indicates the existence of a second human homologue on chromosome arm 9q and a Caenorhabditis elegans homologue. Northern blot analysis indicates that both the human and the murine homologues produce an mRNA species of congruent with9.5 kb expressed in brain, heart, and skeletal muscle and during mouse embryonic development. The conserved structural characteristics of the BICD1 protein and its expression in muscle and especially brain suggest that BICD1 is a component of a cytoskeleton based mRNA sorting mechanism conserved during evolution. PMID- 9367687 TI - DNA sequence, chromosomal localization, and tissue expression of the mouse proteasome subunit lmp10 (Psmb10) gene. AB - Proteasomes are nonlysosomal multicatalytic proteases involved in antigen processing. Three of the 10 mammalian proteasome beta subunits (LMP2, LMP7, and LMP10) are induced by IFN-gamma. Two of these (LMP2 and LMP7) are encoded in the major histocompatibility complex of both human (chromosome 6) and mouse (chromosome 17). However, the human homologue of Lmp10, MECL1, is found on chromosome 16. Here we show that in mice, Lmp10 is a single-copy gene localized to chromosome 8, in a region of conserved synteny with human chromosome 16. Sequencing of a 129/SvJ strain genomic clone revealed that the gene has eight exons spanning 2.3 kb. Characterization of a full-length mouse cDNA clone indicates that Lmp10 encodes a protein of 273 amino acids with a calculated molecular weight of 29 kDa and an isoelectric point of 6.86. Northern analysis of Lmp2, Lmp7, and Lmp10 showed expression in heart, liver, thymus, lung, and spleen, but not in brain, kidney, skeletal muscle, or testis. PMID- 9367686 TI - Identification of a gene (GPR30) with homology to the G-protein-coupled receptor superfamily associated with estrogen receptor expression in breast cancer. AB - Using the technique of differential cDNA library screening, a cDNA clone was isolated from an estrogen receptor (ER)-positive breast carcinoma cell line (MCF7) cDNA library based upon the overexpression of this gene compared to an ER negative cell line (MDA-MB-231). Sequence analysis of this clone determined that it shared significant homology to G-protein-coupled receptors. This receptor, GPCR-Br, was abundantly expressed in the ER-positive breast carcinoma cell lines MCF7, T-47D, and MDA-MB-361. Expression was absent or minimal in the ER-negative breast carcinoma cell lines BT-20, MDA-MB-231, and HBL-100. GPCR-Br was ubiquitously expressed in human tissues examined but was most abundant in placenta. GPCR-Br expression was examined in 11 primary breast carcinomas. GPCR Br was detected in all 4 ER-positive tumors and only 1 of 7 ER-negative tumors. Based upon PCR analysis in hybrid cell lines, the gene for GPCR-Br (HGMW-approved symbol GPR30) was mapped to chromosome 7p22. The pattern of expression of GPCR-Br indicates that this receptor may be involved in physiologic responses specific to hormonally responsive tissues. PMID- 9367688 TI - Rab17 and rab18, small GTPases with specificity for polarized epithelial cells: genetic mapping in the mouse. AB - The Rab subfamily of small GTPases plays an important role in the regulation of membrane traffic in eukaryotic cells. While most Rab proteins are equally expressed in polarized and nonpolarized cells, Rab17 and Rab18 show epithelial cell specificity. Here we report the genetic mapping of Rab17 and Rab18 on mouse chromosomes 1 and 18, respectively. We also discuss some implications of Rab17 and Rab18 mapping, including their candidacy for the mouse mutations ln (leaden), Tw (twirler), and ax (ataxia). PMID- 9367689 TI - Identification of quantitative trait loci controlling levels of radiation-induced thymocyte apoptosis in mice. AB - Thymocyte apoptosis levels are higher in C57BL/6J mice than in C3Hf/Kam mice. Low dose irradiation increases the numbers of thymocytes undergoing apoptosis, but the strain difference persists. We mapped three loci controlling radiation induced thymocyte apoptosis levels in F2 intercross progeny of these strains. The strongest association of a genomic region with an apoptosis level occurred in a region of chromosome 11 known to harbor a locus (or loci) important in the pathogenesis of several rodent models of autoimmune disease. Additional loci influencing radiation-induced thymocyte apoptosis were identified on chromosomes 9 and 16. The genetic polymorphisms underlying these loci may have an evolutionary role in fine-tuning the apoptotic response in T cells and may be important in the etiology of lymphoproliferative disorders and autoimmunity. PMID- 9367690 TI - Assignment of the glial inwardly rectifying potassium channel KAB-2/Kir4.1 (Kcnj10) gene to the distal region of mouse chromosome 1. PMID- 9367691 TI - RREB1, a ras responsive element binding protein, maps to human chromosome 6p25. PMID- 9367692 TI - Genetic predisposition testing: taking the lead. PMID- 9367693 TI - High frequency of BRCA1 and BRCA2 germline mutations in Ashkenazi Jewish ovarian cancer patients, regardless of family history. AB - To better understand the role of germline BRCA mutations in ovarian cancer in Ashkenazi Jews, we tested 29 consecutive patients admitted to our service for the three mutations common in this ethnic group. These mutations are 185delAG and 5382insC in BRCA1 and 6174delT in BRCA2. Six patients had both breast and ovarian cancer, and 23 had ovarian cancer only. In the first group, all women had germline mutations, 2 with each mutation. Of 23 ovarian cancer patients, 11 were carriers (48%): 6 of 185delAG, 2 of 5382insC, and 3 of 6174delT. Regarding family history, of 13 women with no family history, 3 (23%) were carriers. Of 10 women with any family history of breast or ovarian cancer, 8 (80%) were carriers. We discuss possible explanations for this surprisingly high carrier rate, including a high proportion of familial disease coupled with lack of adequate family history, lower penetrance than previously expected, or increasing penetrance in recent generations due to nongenetic factors. Our data suggest that genetic testing is merited in all Ashkenazi women with ovarian cancer, regardless of family history. PMID- 9367694 TI - Phase I study of tirapazamine and cisplatin in patients with recurrent cervical cancer. AB - OBJECTIVES: Tirapazamine (SR 4233) is a benzotriazine compound exhibiting substantial differential toxicity for hypoxic cells. A large enhancement in tumor cell killing has been demonstrated in preclinical studies when tirapazamine was combined with cisplatin. This phase I study was undertaken to establish a safe dose combination of tirapazamine and cisplatin when administered to patients with recurrent cervical carcinoma. METHODS: Tirapazamine was administered as an intravenous infusion over 2 hr, followed 1 hr later by cisplatin intravenously over 1 hr, every 21 days. All patients received prophylactic antiemetics consisting of ondansetron, dexamethasone, and lorazepam. The planned dose escalation levels of tirapazamine were 195, 260, 330, and 390 mg/m2. The cisplatin dose was fixed at 75 mg/m2. RESULTS: A total of 12 patients were treated with 43 courses of therapy. Patients were heavily pretreated. Eleven of the 12 had prior radiotherapy and 5 of the 12 had prior cisplatin-based chemotherapy. A maximally tolerated dose of 330 mg/m2 was defined for this patient population. The dose-limiting toxicity was nausea and vomiting. All 12 patients were also evaluated for response. Two major responses were seen (17%). In addition, there were three minor responses (25%) and 4 patients achieved disease stabilization (33%). All major and minor responses were seen at the highest dose level tested of 330 mg/m2. CONCLUSIONS: Tirapazamine and cisplatin is an interesting drug combination in the treatment of cervical cancer. Phase II testing is planned. PMID- 9367695 TI - Phase I trial of taxol as a radiation sensitizer with cisplatin in advanced cervical cancer. AB - OBJECTIVE: The aim of this study was to determine tolerable doses and potential toxicities of taxol, administered weekly, with concomitant cisplatin and radiation therapy in advanced cervical cancer. METHODS: Patients with cervical cancer, either with evidence of distant metastatic disease at presentation or otherwise at high risk for recurrent disease, were eligible for this phase I study. Taxol was administered weekly as a 3-hr intravenous infusion in addition to the prescribed radiation therapy. The starting dose was 10 mg/m2/week and escalated at 10 mg/m2/week increments if tolerated by successive cohorts of three new patients. Cisplatin was given every 3 weeks at 50 mg/m2. Chemotherapy was continued until radiation was completed. For each patient quality of life was assessed weekly during therapy. RESULTS: Sixteen patients, undergoing a total of 102 cycles, have been enrolled. Dose escalation of taxol from 10 mg/m2/week to 50 mg/m2/week was well tolerated, with no significant change in quality of life during therapy. Two radiation fractions (0.5%) were delayed due to toxicity from this chemotherapy regimen. Of 102 cycles, 6 resulted in grade 2 and 1 in grade 3 neutropenia, and no patient developed >grade 2 anemia or thrombocytopenia. Three patients developed GI-related toxicities and 1 patient presented with urosepsis during treatment. There was a 93% response rate to this regimen, with 10 patients (63%) presently having no evidence of disease. CONCLUSIONS: This study has demonstrated that up to 50 mg/m2/week of taxol is well tolerated in patients undergoing radiation therapy for advanced cervical cancer. A phase II trial will assist in determining the efficacy of taxol as a radiation sensitizer in these patients. PMID- 9367696 TI - A retrospective review of paclitaxel-associated gastrointestinal necrosis in patients with epithelial ovarian cancer. AB - Seven patients with gastrointestinal necrosis following paclitaxel chemotherapy are reported. Four of seven patients had platinum refractory disease, while 3/7 patients received primary paclitaxel therapy. Complications occurred 5 to 16 days following paclitaxel therapy. The most common clinical presentation was fever (7/7 patients), neutropenia (6/7 patients), and abdominal pain (6/7 patients). All seven patients developed gastrointestinal necrosis following the first cycle of paclitaxel chemotherapy. The exact mechanism by which this complication occurs is poorly understood. We postulate that gastrointestinal necrosis may be the result of a direct drug effect on the gastrointestinal epithelium and might involve a synergistic interaction between compromised bowel and paclitaxel induced mitotic arrest. We observe that the incidence of gastrointestinal necrosis in patients with platinum refractory disease is 4 of 108 patients (3.7%). The incidence of this complication in patients receiving primary paclitaxel at our institution is 3 of approximately 128 patients (2.3%). Eighteen cases to date have been identified in the literature. A high index of suspicion of this complication should be considered for patients presenting with neutropenic fever and abdominal pain following paclitaxel chemotherapy. PMID- 9367697 TI - Two sequential studies for primary peritoneal carcinoma: induction with weekly cisplatin followed by either cisplatin-doxorubicin-cyclophosphamide or paclitaxel cisplatin. AB - OBJECTIVES: The aim of the current study is to evaluate the results of therapy with induction with weekly cisplatin followed by the combination of cisplatin doxorubicin-cyclophosphamide (PAC) or the combination paclitaxel-cisplatin (TP) as first-line chemotherapy in patients with primary peritoneal adenocarcinoma (PPA). METHODS: Between October 1988 and July 1996, 46 patients with PPA were treated with PAC (n = 25) or TP (n = 21) following cytoreductive surgery in two sequential trials. In trial 1, patients received induction with weekly cisplatin (1 mg/kg) x 4 followed by monthly cisplatin (50 mg/m2), cyclophosphamide (750 mg/m2), and doxorubicin (50 mg/m2) for 10 cycles. In trial 2, patients received induction with weekly cisplatin (1 mg/kg) x 4 followed by monthly cisplatin (75 mg/m2) and paclitaxel (135 mg/m2) over 24 hr for 6 cycles. Surgical assessment of response was performed in 15 (60.0%) and 13 (61.9%) patients in the PAC and TP trials, respectively. Estimated survival and progression-free survival distributions were calculated by the method of Kaplan and Meier. Survival curves were compared using the log rank test. RESULTS: There were no significant differences between patients in either treatment arm with respect to median age, substage, percentage of patients undergoing optimal cytoreductive surgery, median preoperative CA125 values, performance status, proportion of patients who had second-look procedures, or median cumulative doses of cisplatin. The incidence of nausea and vomiting as well as peripheral neuropathy was significantly higher among patients who received TP (P = 0.005 and 0.022, respectively). The overall response, surgical response, and complete surgical response were not statistically different among patients who received PAC and those who received TP (62.5% versus 70.0%, P = 0.75, 73.3% versus 76.9%, P = 0.1, and 13.3% versus 23.1%, P = 0.64, respectively). Patients who underwent optimal cytoreductive surgery demonstrated higher response than patients whose tumors could not be optimally cytoreduced (76.7% versus 42.9%, P = 0.04). There was no statistically significant difference in overall survival or time to progression/recurrence between the PAC and TP groups (median 21.5 versus 24.0 months, P = 0.68, and 17.3 versus 24.0 months, P = 0.59, respectively). In both treatment groups combined, 18 of 32 patients whose tumors were optimally cytoreduced and 3 of 14 patients whose tumors were suboptimally cytoreduced had surgically verified response. Patients who underwent optimal cytoreductive surgery exhibited longer survival than those who underwent suboptimal cytoreductive surgery (median 29.4 versus 18.6 months, P = 0.008). CONCLUSIONS: Both PAC and TP regimens are effective combinations in patients with PPA. The median survival was similar following PAC and TP but the responses and time to recurrence/progression were nonsignificantly better in the paclitaxel combination. PMID- 9367698 TI - Characterization of highly radiosensitive cell lines from a human ovarian small cell cancer. AB - Cells were obtained at paracentesis from a patient with a rapidly growing ovarian tumor. A monolayer cell line (V7S), a xenograft tumor line (V7), and subsequently a xenograft-derived monolayer cell line (V7M) were established. Histological and immunohistochemical studies of the original tumor, xenograft, and cell lines provided a diagnosis of small-cell carcinoma of the ovary-which is consistent with the clinical course of the patient. V7S and V7M had a predominantly hypodiploid karyotype with a small tetraploid population. The V7M, which has been in long-term culture, also showed a nonrandom translocation involving chromosomes 1 and 14 and monosomy of X. Radiobiologically, V7S, V7, and V7M showed marked radiosensitivity with surviving fractions at 2 Gy, measured by clonogenic assay, of between 0.022 and 0.147. Split-dose experiments provided evidence that this radiosensitivity was not due to an inability in cellular repair. In vivo data from the xenograft (V7) revealed a highly radiosensitive tumor, corroborating the in vitro studies. PMID- 9367699 TI - Radiotherapy for centrally recurrent cervical cancer of the vaginal stump following hysterectomy. AB - PURPOSE: This study was performed to establish the classification and the treatment modality for recurrent cervical cancer of the vaginal stump after hysterectomy. PATIENTS AND METHODS: Ninety patients with centrally recurrent cervical cancer of the vaginal stump following hysterectomy were treated with high-dose-rate intracavitary brachytherapy with or without external irradiation. The intervals between primary surgery and vaginal recurrences varied from 3 months to 36 years. Tumor size of the vaginal stump was determined by bimanual rectovaginal examination at the time of recurrence and was classified into three groups, i.e., small (no palpable tumor), medium (less than 3 cm), and large (3 cm or more). RESULTS: The 10-year survival rates for all patients were 52%. Survival was greatly influenced by the tumor sizes of the vaginal stump. The 10-year survival rates of patients with small, medium, and large size tumors were 72, 48, and 0%, respectively. All patients with large size tumors died within 5 years. Of 90 patients, 75 (83%) were determined by physical examination to be free of tumor on at least one visit within 2 months of the completion of treatment (CR). The remaining 15 patients (17%) had physical findings suggestive of residual tumor (Residual). The overall 10-year survival rate for all patients with CR was 63%, compared with 10% for the patients with Residual (P < 0.0001). The incidences of distant metastases of the patients with or without local failure were 55 and 13%, respectively (P < 0.0001). The patients with local failure had significantly higher incidence of metastases. Most patients with small size tumor were treated with brachytherapy alone, and the survival rates of these patients were not improved by combination with external irradiation. CONCLUSION: These results suggest that tumor size was a significant prognostic factor for recurrent cervical cancer of the vaginal stump. Patients with small size tumors were recommended to be treated with brachytherapy alone. PMID- 9367700 TI - The clinical course of cervical carcinoma in situ diagnosed during pregnancy. AB - OBJECTIVE: The objective was to determine the frequency with which regression or progression of disease without treatment occurred in women diagnosed with squamous cell cervical carcinoma in situ (CIS) during pregnancy. METHODS: . A retrospective chart review of all women evaluated at the University of Iowa Colposcopy Clinic diagnosed with CIS during pregnancy from 1987 through 1992 was used. Thirty-four women were evaluated during pregnancy, of which 26 also had postpartum evaluation. All pathology reports of initial cytology and biopsies, as well as colposcopic impressions, were reviewed and compared to the same evaluations postpartum. RESULTS: Of the 26 women evaluated both antepartum and postpartum, only 1 was treated (cone biopsy) during pregnancy. She had disease suspicious for microinvasion. She was disease free postpartum. Of the remaining 25, 20 (80%) had persistent disease, 2 (8%) had either missed disease or progressive disease postpartum, and 3 (12%) resolved without treatment at postpartum evaluation. No statistical significance was found between route of delivery and persistence (P = 0.34). No statistical significance was found between smoking and persistence of disease (P = 1.0). In 46% of women the initial cytology was CIN I or II, and the initial colposcopic impression was found to underestimate the severity of the disease in 35% of cases. Two women were found to have invasive disease postpartum. CONCLUSIONS: There is a high persistence rate of CIS complicating pregnancy. Given the relatively high rate of underestimation of disease severity by both cytology and colposcopic impression, the use of routine biopsy at the time of colposcopy is recommended. Invasive disease may be encountered on postpartum evaluation. PMID- 9367701 TI - Modified radical vulvectomy without lymphadenectomy under local anesthesia in medically compromised patients. AB - INTRODUCTION: Our objective was to review our experience with vulvar cancer treated with modified radical vulvectomy without lymphadenectomy under local anesthesia and sedation. METHODS: A retrospective review of surgical case lists revealed five patients who underwent modified radical vulvectomy without lymphadenectomy under local anesthesia with sedation. All patients had significant medical diseases which precluded regional or general anesthesia. Modified radical vulvectomy was performed in standard fashion under sedation and local anesthesia. Inguinal lymphadenectomy was not performed. RESULTS: Median operative time was 1.5 h and median blood loss was 100 cc. Median diameter of tissue resected was 5 cm and median depth was 5 cm. Median length of hospital stay was 4 days. No patient complained of pain during the operative procedure. At a median follow-up of 2.5 years, there has been one local recurrence. CONCLUSION: Five patients with symptomatic vulvar cancer who were not candidates for regional or general anesthesia underwent modified radical vulvectomy without lymphadenectomy under local anesthesia with sedation. The procedure was well tolerated and produced minimal morbidity and adequate short-term local control. PMID- 9367702 TI - Ifosfamide plus cisplatin as primary chemotherapy of advanced ovarian cancer. AB - We have performed a phase II study to evaluate the activity and toxicity of ifosfamide and cisplatin as first-line treatment for advanced ovarian cancer. Patients were treated with cisplatin 100 mg/m2 on day 1 and ifosfamide 5 g/m2 in 18-hr continuous infusion on day 1 or 1.5 g/m2 bolus on days 1-5. Between August 1988 and March 1990, 30 women were entered in the trial, 26 of them with measurable disease. The overall clinical response rate was 69% (95% CI: 48-85%), including 34.6% complete responses (95% CI:17-55%). Reassessment laparotomy was performed in 12 cases, and 4 (33%) exhibited a pathologic complete response. For all patients, the median duration of progression-free survival was 14 months, and the median overall survival was 25 months. There were no major differences in the response rate or survival between the two ifosfamide administration modalities. Relevant toxicities were grade IV hematologic toxicity in 11/30 patients and grade IV renal toxicity in 2/30 patients. A patient with grade IV encephalopathy developed a trauma-related cerebral hemorrhage and died 2 months later. The combination of ifosfamide and cisplatin is active in first-line therapy in advanced ovarian cancer, although it does not seem to improve the efficacy or toxicity profile of conventional combinations. PMID- 9367703 TI - A randomized, multicenter, double-blind, placebo-controlled, dose-finding study of ORG 2766 in the prevention or delay of cisplatin-induced neuropathies in women with ovarian cancer. AB - OBJECTIVE: The objective was to evaluate the efficacy of Org 2766 (a hexapeptide analogue of ACTH) in the prevention or delay of cisplatin-induced neuropathy during chemotherapy in women with ovarian cancer as measured by vibration perception threshold (VPT). METHODS: In this randomized, multicenter, double blind, placebo-controlled study, 196 women with ovarian cancer were treated with cisplatin 75-100 mg/m2, cyclophosphamide 600-1000 mg/m2 plus placebo or two dose levels of Org 2766. The cisplatin-induced neuropathies were monitored by determining the VPT with the Vibratron II. VPT was determined for both the most sensitive great toe and the index finger on a monthly basis during treatment and months 1, 2, and 3 postchemotherapy. Once the blind was broken, it was found that 174 women (59 in placebo, 58 in 2 mg, and 57 in 4 mg) had enough data to allow evaluation. RESULTS: Over the course of follow-up, the VPT was found to increase. This is consistent with the development of cisplatin-induced peripheral neuropathies. The baseline VPT for the index finger was less than that of the great toe (0.65 vs 2.13), but the percentage change in VPT was the same for both (percentage increase in VPT of about 350%). When the VPTs are compared according to the dose of Org 2766 given, there appears to be no difference in the rate of change or degree of neuropathies that developed in these women receiving cisplatin and cyclophosphamide. CONCLUSIONS: The development of cisplatin-induced neuropathies is confirmed by measurement of the VPT. The rate of development of neuropathies seems to accelerate after the sixth course of cisplatin. When the development of neuropathies is evaluated on the basis of Org 2766 dosage, it is found that there is no difference in the rate or degree of neuropathies seen. Instead of providing protection from and delay of onset of peripheral neuropathies caused by cisplatin, these results suggest that the administration of Org 2766 appears to cause an increase in the rate of change and degree of neuropathies (P > 0.05). PMID- 9367704 TI - Human papillomavirus infection in squamous cell carcinoma of the vulva, in various synchronous epithelial changes and in normal vulvar skin. AB - OBJECTIVE: To investigate the prevalence of human papillomavirus (HPV) infection in various vulvar lesions. METHODS: HPV infection using consensus primer-PCR was studied in 66 patients with vulvar carcinoma and in the synchronous epithelial lesions. RESULTS: HPV infection was present in 13/66 carcinoma, in 1/33 VIN I, in 3/11 VIN II, in 8/16 VIN III, in 2/30 lichen sclerosus, in 1/37 squamous cell hyperplasia, and in 2/55 normal skin specimens. Normal skin from healthy controls showed HPV-negative specimens only. Patients with HPV-positive carcinomas were younger, presented in lower stages, and had high-grade VIN more often than those with HPV-negative carcinomas. CONCLUSIONS: In sum we found that all types of epithelial changes synchronous with carcinoma of the vulva showed HPV infection, indicating that they all might have malignant potential. PMID- 9367705 TI - MIB 1 immunostaining in cervical carcinoma of young patients. AB - OBJECTIVE: In the present study, we assessed whether biologic characteristics of tumors in young patients differ from those observed in older patients with the same clinical and histologic characteristics, but ranging in age from 50 to 70 years. The hypothesis to be verified was whether cervical carcinoma in young patients presented an increased proliferative activity which might explain more aggressive behavior. MATERIALS AND METHODS: Locally advanced cervical carcinoma tumor samples were obtained from our series of patients, maximum age 40 years, and immunohistochemically evaluated by monoclonal MIB 1 antibody (Immunotech, Marseille Cedex, France) on microwave-oven-processed Formalin-fixed paraffin embedded tissue. Positive staining was expressed as a percentage of positive cells per 10(3) counted neoplastic cells for each case. For each young patient, a control was selected among patients aged >/=50 years (range 50-70) matched for stage, tumor size, histologic type and grading, and lymphvascular invasion. RESULTS: Fourteen of 73 patients (19.2%) with stage I and IIa cervical carcinoma who underwent primary radical surgery at our Institute between 1986 and 1994 were aged =40 years. The MIB 1 index was significantly higher in young patients with respect to the older group (mean +/- standard deviation, 61.6 +/- 16.3% and 45.2 +/- 12.2%, with P = 0.006). CONCLUSIONS: Although any conclusions from this study need to be tempered because of the small number of patients involved, locally advanced cervical carcinomas present in young patients showed a more aggressive biologic behavior, expressed by a higher cell proliferation index. PMID- 9367706 TI - Initial immunochemical characterization of MX35 ovarian cancer antigen. AB - Monoclonal antibody (mAb) MX35 reacts with approximately 90% of ovarian epithelial cancers and has been studied in localization and biodistribution trials in ovarian cancer patients. This study shows that mAb MX35 recognizes a cell surface antigen of about 95,000 D on OVCAR-3 ovarian cancer cells. The antigen could be immunoprecipitated from lysates of cells metabolically labeled with [3H]glucosamine and it bound to concanavalin A and wheat germ agglutinin lectins, showing that it is a glycoprotein. MX35 antigen can also be detected in detergent lysates of OVCAR-3 cells by Western blotting. Using this technique the MX35 epitope(s) was shown to be heat stable but susceptible to reduction by 2 mercaptoethanol. Protease digestion of the antigen resulted in smaller fragments (42-52 kDa) that still reacted with antibody. We conclude that MX35 antigen is a 95 kDa glycoprotein, stabilized by disulfide bonds, with a large protease resistant region that carries the MX35 epitopes. PMID- 9367707 TI - Biochemical characterization of primary peritoneal carcinoma cell adhesion, migration, and proteinase activity. AB - Primary papillary serous carcinoma of the peritoneum (PPC) is clinically and histologically similar to advanced stage epithelial ovarian carcinoma. PPC classically presents with widespread intraperitoneal dissemination, superficial invasion, and minimal ovarian involvement. Surgical cytoreduction and combination chemotherapy utilized for patients with epithelial ovarian carcinoma have produced varying results for patients with PPC. These differences in response may be secondary to the stage of disease or due to biological differences in metastatic behavior between these carcinomas. In this study, short-term primary cultures of PPC and epithelial ovarian carcinoma (OVCA) were compared to enable biochemical comparison with respect to components of the metastatic cascade including adhesion, migration, and proteinase activity. These data demonstrated similar properties in adhesive profiles of PPC and OVCA, with preferential adhesion to type I collagen and vitronectin. Matrix-degrading proteinases including matrix metalloproteinases (MMP)-2, MMP-9, and urinary-type plasminogen activator were produced by both cell types. PPC migration was stimulated by multiple extracellular matrix proteins, whereas OVCA cells demonstrated maximal migration on type I collagen coated surfaces. Together our data suggest biochemical similarities between PPC and OVCA with respect to individual components of the metastatic cascade. PMID- 9367708 TI - S-Phase fraction, p53, and HER-2/neu status as predictors of nodal metastasis in early vulvar cancer. AB - OBJECTIVE: Our aim was to determine the value of the S-phase fraction, p53, and HER-2/neu status as predictors of inguinal nodal metastasis in early vulvar cancer. METHODS: The charts of 100 consecutive patients with invasive squamous cell cancer of the vulva were reviewed and a cohort of patients with clinical stage I or II disease treated primarily with radical surgery and inguinal node dissection was identified. Within this cohort, all node-positive patients were matched with node-negative controls by depth of invasion. Tumor from the 13 node positive patients and 26 controls was then analyzed by flow cytometry and immunohistochemistry. RESULTS: The median value of the S-phase fraction was higher in tumor from patients with inguinal nodal metastasis (median, 18.2; 25th 75th percentile: 13.9-28.3) than in node-negative patients (median, 8.9; 25th 75th percentile: 5.4-15.6) (P = 0.01). The presence of the HER-2/neu immunopositivity was also found to be associated with nodal metastasis (OR 4.05, 95% CI 1.0-16.6), but we found no evidence that DNA index or the presence of p53 immunopositivity was associated with nodal metastasis. CONCLUSION: Early vulvar cancer patients with inguinal node metastasis have a significantly higher S-phase fraction and are more likely to have HER-2/neu immunopositivity when compared to those without nodal metastasis. PMID- 9367710 TI - Does debulking surgery improve survival in biologically aggressive ovarian carcinoma? AB - Aggressive tumor reduction surgery has been widely used in patients with advanced stage epithelial ovarian carcinoma before initiation of cytotoxic chemotherapy. No randomized controlled trial has been carried out to confirm the benefits of such procedures. To examine the role of cytoreductive surgery in the management of stage 2 and 3 patients with epithelial ovarian carcinoma treated with postoperative adjuvant platinum-based chemotherapy, survival analysis was carried out on patients with initial microscopic disease documented on staging laparotomies, patients with large volume of disease at time of exploration and tumor reduced to microscopic residuals, and patients who were suboptimally debulked with more than 2-cm residual disease. Twenty-four, 81, and 191 patients were identified from a computerized data base, respectively. Kaplan-Meier survival estimates showed that 62% with initial microscopic residual are alive with no evidence of disease at 5 years and 56% of patients left with microscopic residuals after tumor reduction are alive and well at 5 years. There was no statistical significant difference between these two groups. The groups are equivalent with respect to known adverse prognostic factors. In contrast, 5-year survival in the suboptimal debulked group was significantly lower at 15%. Debulking surgery to achieve microscopic residual disease improved the prognosis in patients with initial large volume of disease. Survival was similar to survival in patients with microscopic disease at time of exploration. The beneficial effect may be attributed to the removal of chemoresistant clones in bulky tumors. Tumor reduction surgery remains important in the management of advanced stage epithelial ovarian carcinoma. PMID- 9367709 TI - Extended field radiation and cisplatin for stage IIB and IIIB cervical carcinoma. AB - OBJECTIVE: The aim of this study was to investigate local regional control, survival, and morbidity in patients with FIGO IIB and IIIB squamous cell carcinoma of the cervix treated with primary extended field (prophylactic paraaoratic radiation) radiation and weekly cisplatin. METHODS: Sixty-seven patients (44 IIB and 23 IIIB) with carcinoma of the cervix received cisplatin at 1 mg/kg (up to 60 mg) weekly and extended field radiation therapy including the paraaortic nodes and brachytherapy. RESULTS: After the scheduled therapy 94.1% of the patients were complete responders. Seventy-five percent are alive without evidence of disease with a mean follow-up of 47.5 months. CONCLUSION: This study confirms the ability to give concomitant weekly cisplatin and prophylactic paraaortic radiation with minimal morbidity. The encouraging Kaplan-Meier survival of 75% and only eight pelvic failures warrants further investigation. PMID- 9367712 TI - Endometrioid ovarian carcinoma in a premenarchal girl: report of a case. AB - In children and adolescents, ovarian neoplasms are predominantly germ cell and sex cord stromal tumors. Carcinomas are quite rare, and, in particular, endometrioid adenocarcinomas are extremely rare in this age group. We report the case of a 13-year-old girl with FIGO stage I, grade I endometrioid adenocarcinoma of the ovary. To our knowledge this is the first report of an endometrioid carcinoma of the ovary occuring in the premenarchal age group and only the second case reported before age 15. Our patient has been treated by conservative surgery without postoperative chemotherapy. Menarche occured 3 months after surgery. Twelve months after surgery she is free of disease. PMID- 9367711 TI - Loss of heterozygosity of the retinoblastoma and p53 genes in primary cervical carcinomas with human papillomavirus infection. AB - OBJECTIVE: Paired DNA samples from 55 primary uterine cervical carcinomas and normal bloods were studied for chromosomal allelic loss (loss of heterozygosity; LOH) of the retinoblastoma (Rb) and p53 gene loci by polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism analysis. All the study samples contained at least one of the oncogenic human papillomavirus (HPV) type 16 and/or 18 sequences. And the relationships between allelic losses of these genes and conventional clinicopathological parameters were evaluated. METHODS: In order to detect LOH of the Rb gene in cervical cancers, we analyzed four polymorphic intronic sites (intron 1, 17, 20, and 25) of the Rb gene and one additional microsatellite near the Rb locus (D13S118). For detection of the LOH in p53, three intragenic polymorphisms (exon 1, exon 4, intron 6) and one microsatellite distal to the p53 gene (D17S5) were examined. RESULTS: By analyzing this system, we could increase the heterozygosity of the Rb and p53 loci up to 0.91 and 1, respectively. The observed allelic loss rates of the Rb and p53 loci in informative cases were 14% (7/50) and 5.5% (3/55), respectively. The patients with LOH at the D13S118 locus also had the allelic loss of the Rb gene, whereas only one of the four patients with LOH at the D17S5 locus showed a concomittant allelic loss of the p53 gene. The frequency of cervical cancer with one LOH at the Rb or p53 loci was 20% (11/55). No shifted bands were observed in the PCR-single-strand conformation polymorphism analysis of the p53 gene. The LOH of the Rb or p53 gene was not significantly associated with other parameters including clinical stage, histological type, degree of differentiation, status of HPV infection, and p53 gene mutation. CONCLUSION: Concerning the results above, we conclude that the allelic imbalance of the Rb or p53 gene itself is not implicated as a major contributing factor in the malignant transformation or the tumor progression in HPV-positive uterine cervical cancers. PMID- 9367713 TI - Ovarian mucinous cystadenoma associated with mural leiomyomatous nodule and massive ovarian edema. AB - Mural nodules associated with mucinous and serous tumors of the ovary may represent a reactive process, a benign tumor, or a malignant neoplasm. Mural leiomyomatous nodule in mucinous cystadenoma is extremely rare. Two such cases had been described previously. In this case a 43-year-old white female presented with 24-h history of left quadrant pain and a left adenexal cystic mass on ultrasound examination. An exploratory laparotomy revealed a left ovarian mass with torsion on its pedicle. Frozen section of the cystic mass showed a mucinous cystadenoma with mural smooth muscle proliferation. A total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed. Histologic examination of the mass revealed a mucinous cystadenoma with a mural leiomyomatous nodule and an enlarged ovary with massive stromal edema. This is the first case of a mural leiomyomatous nodule in association with a mucinous cystadenoma in an ovary with massive edema. This case broadens the histologic spectrum in which a mural leiomyomatous nodule may be encountered. PMID- 9367714 TI - Cisplatin, epirubicin, and ifosfamide versus cisplatin, epirubicin, and cyclophosphamide in clear cell carcinoma of the ovary. PMID- 9367715 TI - Effects of estradiol-17beta and progesterone on mating behavior in female lesser bushbabies (Galago moholi) in captivity. AB - The effects of ovariectomy, estradiol-17beta, and progesterone on female sexuality were investigated in a prosimian primate, the lesser bushbaby (Galago moholi). Each of eight ovariectomized, adult bushbabies was pair-tested with a male partner in the absence of hormone treatment, during estradiol-17beta (E2) treatment (3.125 microg/0.1 ml), and during E2 + progesterone (0.125 mg/0.1 ml) treatment. Pretreatment females were sexually nonreceptive and nonattractive toward the males. In contrast, E2 treatment elicited vaginal opening, partial or complete epithelial cell cornification, and female receptivity in all females and elicited the complete mating repertoire in seven pairs. Progesterone treatment opposed the facilitatory effects of E2 by inhibiting female receptivity and epithelial cell cornification and inducing vaginal closure. Behaviors were quantified following changes in hormone treatment, vaginal physiology, and the presence or absence of intromission. Female attractiveness (male sexual arousal) was initiated during vaginal swelling and was maintained for the duration of vaginal opening, while female receptivity was manifested exclusively during the period of vaginal opening. Female proceptive behavior was mainly associated with the period of receptivity. This study provided evidence of a strict hormonal regulation of both behavioral and nonbehavioral aspects of female sexuality in a prosimian. PMID- 9367716 TI - Cortisol, hedonics, and maternal responsiveness in human mothers. AB - New mothers are more attracted to the body odor of newborn infants than are nonmothers. In this study we investigated the relation of postpartum hormones and of prior experience with infants to this enhanced maternal attraction to infant odors. New mothers were asked to complete a hedonics task, using a pleasantness scale to provide an attraction score to different odorants presented on a cotton substrate in a 1-pt Baskin-Robbins container. Mothers were "blind" to the contents of the container. Participants also completed an extensive set of 100 item likert scales concerning their attitudes toward infants, care taking, own maternal adequacy, and other interpersonal relations. Mothers were videotaped interacting with their infants and provided salivary samples prior to the interaction. Salivary samples were assayed by radioimmunoassay (RIA) for salivary concentrations of cortisol, progesterone, and testosterone. Results show that first-time mothers with higher cortisol concentrations were more attracted to their own infant's body odor. Mothers with higher cortisol levels were also better able to recognize their own infants' odors. While cortisol was not related to attitudinal measures of maternal responsiveness, mothers with more prior experience interacting with infants exhibited both more attraction to infant odors and more positive maternal attitudes. Together, prior maternal experience and postpartum cortisol explain a significant proportion of the variance in mothers' attraction to newborn infant odors. These relations are discussed in terms of the variety of "meanings" cortisol could have during the postpartum period. PMID- 9367717 TI - Differential effects of arginine vasotocin and gonadotropin-releasing hormone on sexual behaviors in an anuran amphibian. AB - Both arginine vasotocin (AVT) and gonadotropin-releasing hormone (GnRH) are known to influence sexual behavior in many vertebrate taxa. We investigated the effects of both of these peptides on two different sexual behaviors, calling and amplexus, in the Great Plains toad (Bufo cognatus). AVT, at a dosage of 100 microg/100 g toad, significantly increased both the amount of calling behavior per individual and the probability that an individual would call. GnRH, however, had no effect on calling behavior. There was a reciprocal effect of these peptides on amplexus: AVT did not induce amplexus, while GnRH significantly induced this behavior. Furthermore, AVT-induced calling could be inhibited by Manning compound (an arginine vasopressin receptor antagonist). This is the first report of GnRH influencing sexual behavior in an anuran amphibian. These results suggest that specific sexual behaviors in B. cognatus may be under the regulation of independent peptide control. PMID- 9367718 TI - Localization of progesterone receptor in brain and pituitary of the ring dove: influence of breeding cycle and estrogen. AB - An immunocytochemical method was used in male and female ring doves (Streptopelia risoria) to localize progesterone receptor immunoreactivity (PR-ir) in the brain and anterior pituitary gland in nonbreeding, incubating, brooding, and estrogen (E2)-treated nonbreeding birds. Progesterone receptor was found in four regions of the brain in males and females: the preoptic area (POA), nucleus preopticus paraventricularis magnocellularis (PPM), nucleus hypothalami lateralis (PLH), and the tuberal region (TR). Quantitative analysis demonstrated that the density of cell nuclei containing PR-ir in the POA, PPM, and PLH in brooding birds was significantly higher than in E2-treated doves or in birds at other stages of the reproductive cycle. The density of PR-containing cell nuclei in the TR of male ring doves was significantly higher on day 1 of incubation than in nonincubating males. In brooding birds, there was a significant decrease in PR-ir in the TR, particularly in the ventral region where nuclei containing PR-ir disappeared. In the anterior pituitary gland the density of cell nuclei containing PR-ir was higher in females than in males at the onset of incubation. E2 treatment resulted in an increase in the density of PR-containing cell nuclei in both males and females. Brooding females had a lower concentration of PR-containing cell nuclei than did females at other stages of the breeding cycle. It is suggested that progesterone receptor in the POA mediates the expression of incubation behavior while progesterone receptor in the TR is involved in the control of neuroendocrine function. The source of estrogen which increases PR appears to be of central nervous origin in the male and may be predominantly peripheral in the female. PMID- 9367719 TI - Hormonal activation of the striatum and the nucleus accumbens modulates paced mating behavior in the female rat. AB - Sexual behavior in the female rat has both sensorimotor and motivational components, which can be distinguished when the female rat is able to pace the rate of copulation. The experiments reported were conducted to determine whether estrogen application to the striatum and/or nucleus accumbens affects pacing behavior. In order to induce sexual receptivity, ovariectomized rats received sequential bilateral implants of 17beta-estradiol followed by progesterone into the ventromedial nucleus of the hypothalamus. Then, bilateral implants of 17beta estradiol or cholesterol were administered into either the dorsolateral striatum or the nucleus accumbens. Pacing behavior was tested 4 hr later. It was found that intrastriatal application of estradiol significantly facilitated the percent exits exhibited after copulatory contact, whereas application of estradiol in the nucleus accumbens affected the return latency. To determine whether estrogen in the striatum or nucleus accumbens normally plays a role in pacing behavior, intrastriatal or intra-accumbens implants containing the steroidal antiestrogen ICI 182,780 or vehicle were given to ovariectomized female rats treated systemically with estrogen and progesterone. The antiestrogen treatment decreased the percent exits when delivered to the striatum and affected return latency when delivered to the nucleus accumbens. The results indicate that estrogen acts directly in the striatum and in the nucleus accumbens to differentially modulate specific components of pacing behavior. PMID- 9367721 TI - High testosterone prior to song crystallization inhibits singing behavior in captive yearling dark-eyed juncos (Junco hyemalis). AB - In passerine birds, song is considered crucial in advertising reproductive and territorial status to conspecifics. Variation in the quality and frequency of song may be influenced by hormonal effects during the individual's development. This variation in turn may affect the function and potency of song. We studied the influence of testosterone on vocal production in first-year male dark-eyed juncos (Junco hyemalis), using subcutaneous silastic implants filled with testosterone. Subjects were visually but not acoustically isolated from one another and after capture had no exposure to female or adult male models. Implants were administered when subjects were in the plastic song phase (i.e., after they had begun to sing but before song was fully crystallized). Control males (C males) received empty implants. Experimental males were of two classes: TI males received one dose of testosterone (a single 10-mm implant), and TII males received two doses. Testosterone implants kept plasma levels high well into the breeding season, whereas in nature, levels normally drop after territorial acquisition and pair formation. Control males sang at higher rates than testosterone-treated males of both classes and had the greatest number of song types. This inhibitory effect of testosterone on vocal production suggests that disturbance of seasonal profiles of testosterone in birds may interfere with the production of species-typical song. PMID- 9367720 TI - A potential role of cyclic GMP in the regulation of lordosis behavior of female rats. AB - Nitric oxide (NO) has been suggested to play a crucial role in the regulation of lordosis behavior via stimulation of guanylyl cyclase to synthesize cyclic GMP. Whalen and Lauber (1986, Neurosci. Biobehav. Rev. 10, 47-53) hypothesized that hormones and pharmacological agents known to facilitate lordosis in estrogen primed rodents act through cyclic GMP. The compound 1H-[1,2, 4]oxadiazolo[4,3 a]quinoxalin-1-one (ODQ) has been shown to selectively inhibit NO-stimulated cyclic GMP production. In the present study, we investigated the effects of ODQ on lordosis behavior. Female rats were implanted with a guide cannula aimed at the lateral or third ventricles by stereotaxic surgery, and their ovaries were bilaterally removed. Five days later, animals were injected subcutaneously with 2 microg estradiol benzoate at 48 and 24 hr, and 200 microg progesterone 4 hr before behavioral testing. ODQ or vehicle (1 microl) was administered at the time of progesterone treatment or 20 min before lordosis testing. ODQ significantly decreased lordosis quotients and the quality of lordosis at both intervals of drug infusion. Locomotor activities, measured by line crossing and rearing, were not affected by ODQ. ODQ also inhibited cyclic GMP accumulation in response to NMDA stimulation in hypothalamic and cerebellar slices in vitro. We conclude that cyclic GMP produced by NO generation is an important modulator of female rat sexual behavior. PMID- 9367723 TI - A New Microsporidium, Nosema cristatellae n. sp. in the Bryozoan Cristatella mucedo (Bryozoa, Phylactolaemata) AB - A microsporidian infecting cells of the body wall of the phylactolaemate bryozoan Cristatella mucedo is described. All stages of the parasite are diplokaryotic and lie in direct contact with the host cell cytoplasm. Sporogony is probably disporoblastic. Spores measure 7.5 x 5.1 &mgr;m and have 22-32 coils of the polar tube arranged in several rows and a bell-like polaroplast of compact membranes. The parasite is assigned to the genus Nosema as a new species, Nosema cristatellae. It is differentiated from the previously described parasites of Alcyonella (=Plumatella) fungosa (Bryozoa), named Myxosporidium bryozoides and Nosema bryozoides, by spore characters and tissue specificity. Although it was found in a different species of bryozoan, it is not known whether N. cristatellae is infective to P. fungosa. Copyright 1997 Academic Press. Copyright 1997 Academic Press PMID- 9367722 TI - Characteristics of acyrthosiphon pisum virus, a newly identified virus infecting the pea aphid. AB - A new virus was isolated from the pea aphid, Acyrthosiphon pisum, and tentatively named Acyrthosiphon pisum virus (APV). The isometric virus particles were approximately 31 nm in diameter and contained a single-stranded RNA molecule of approximately 10 kb. Four structural proteins were observed with molecular masses of approximately 23.3, 24.2, 34.5, and 66.2 kDa. The 34.5-kDa capsid protein was the most abundant product in purified virions. Computer-assisted analysis revealed no significant homology between an internal sequence of 37 amino acids of the 34.5-kDa protein of APV and other polypeptides of viral origin. APV was not immunologically related to other ssRNA viruses from hemipteroid insects, such as aphid lethal paralysis virus, Rhopalosiphum padi virus, and Nezara viridula virus type 1. Immunolocalization on ultrathin sections of 3-day-old nymphs of A. pisum showed that APV antigen was predominantly present in the epithelial cells of the digestive tract. Virus particles were also observed associated with the microvilli of the intestine. Occasionally, muscle cells and mycetocyte cells were found infected. Purified APV, fed to 1-day-old A. pisum nymphs, significantly reduced the growth of the aphid and increased the time needed to reach maturity. PMID- 9367726 TI - Occurrence of Merogony of Aggregata Frenzel 1885 (Apicomplexa) in Pleoticus muelleri and Artemesia longinaris (Crustacea: Natantia) from Patagonian Waters (Argentina) AB - The aim of this paper is to describe the merogonic phases of the coccidian Aggregata sp. in the natantians Pleoticus muelleri and Artemesia longinaris from Argentina. Ninety-seven specimens of P. muelleri (from San Jorge Gulf) and 49 of A. longinaris (from Rawson) were examined for intestinal parasites. Intestines were processed under standard histological conditions. The distribution of the octopuses (where gamogony and sporogony of Aggregata spp. take place) in the area considered and the importance of finding these protistans in crustaceans other than brachyurans are also explored. High prevalence values for both hosts indicate that shrimps are the primary hosts for these parasites in Argentinean waters. Copyright 1997 Academic Press. Copyright 1997 Academic Press PMID- 9367728 TI - In Vitro Effects of Secondary Plant Compounds on Germination of Blastospores of the Entomopathogenic Fungus Paecilomyces fumosoroseus (Deuteromycotina: Hyphomycetes) AB - Seven secondary plant compounds (catechol, chlorogenic acid, gallic acid, salicylic acid, saponin, sinigrin, and tannic acid) mixed with Noble agar at three concentrations (100, 500, and 1000 ppm) were tested for their effects on germination of blastospores of the fungal entomopathogen Paecilomyces fumosoroseus. With individual allelochemicals incorporated at 100 ppm in Noble agar, significant differences in time to 95% germination were found between two allelochemicals (catechol and salicylic acid) and the control. Blastospores in media containing 100 ppm catechol took twice as long (10 hr) to reach 95% germination as the control. Germination of blastospores in medium containing catechol, salicylic acid, or tannic acid at 500 was 55, 56, and 46%, respectively, in contrast to less than 10% when the concentration was 1000 ppm. These results indicate that the presence of allelochemicals on a substrate (e.g., insect cuticle or leaf) may be an additional constraint to the survival of entomopathogenic fungi. Copyright 1997 Academic Press. Copyright 1997 Academic Press PMID- 9367727 TI - Isolation, inoculation to insect host, and molecular phylogeny of an entomogenous fungus Paecilomyces tenuipes. AB - A parasitic fungus to moth larvae and pupae, Paecilomyces tenuipes, was isolated and cultured on liquid and agar media. Fruit bodies, or synnemata, with characteristics of P. tenuipes were successfully formed on the agar medium. When pupae of wax moth, Galleria mellonella, were incubated with the conidia, all the pupae were infected and the synnemata were formed out of them. Almost the entire length of 18S rDNA of P. tenuipes was amplified by PCR and directly sequenced. Molecular phylogenetic analysis demonstrated that it belongs to the subphylum Ascomycotina, the class Pyrenomycetes, the order Clavicipitales. This result is compatible with the suggestions that P. tenuipes may be the anamorph of an entomogenous fungus of the genus Cordyceps. PMID- 9367729 TI - Premortality Effects of Zoophthora radicans Infection in Plutella xylostella AB - The effect of Zoophthora radicans infection on food consumption and utilization by Plutella xylostella larvae and oviposition by adults was investigated. Larval food consumption and weight gain were not affected by Z. radicans until the third day after infection, 1 day prior to death from mycosis. No food was eaten on the day on which larvae died. Overall, infected larvae ate 44% less leaf tissue than control larvae. Of the leaf tissue consumed by infected larvae 87.5% was eaten on the first 2 days after infection and after this time infected larvae gained little weight. The efficiency with which ingested food was converted into body weight did not change as infection progressed. Infected female moths laid significantly fewer eggs than control moths. This difference was not only due to differential mortality between the infected and control treatments as the egg production by infected females, until the point of death (Day 4 after infection), was significantly less than that of control females over the same period. Incubating females for 24 hr after eclosion (to allow further egg maturation), prior to infection, did not result in greater overall egg production when compared with moths infected on the day of eclosion. The possible causes for these reductions in larval feeding and adult oviposition rates are discussed. Copyright 1997 Academic Press. Copyright 1997 Academic Press PMID- 9367730 TI - Abundance and Distribution of Bacillus thuringiensis in the Agricultural Soil of Bangladesh AB - Bacillus thuringiensis is distributed ubiquitously in the agricultural soil of Bangladesh. Simple correlation and regression analyses showed that the soil sand percentage and the available copper levels had significant negative and positive contributions, respectively, to the abundance and distribution of B. thuringiensis in the agricultural soil. Among the isolates, only 2.5% of strains showed larvicidal activity against the mosquito Culex quinquefasciatus. The larvicidal potency LD50 varied from 3.5 x 10(3) to 9.5 x 10(7) spores per milliliter among the isolates. Copyright 1997 Academic Press. Copyright 1997 Academic Press PMID- 9367731 TI - Heat-shock response in a molluscan cell line: characterization of the response and cloning of an inducible HSP70 cDNA. AB - Sublethal heat-shock of cells of the Bge (Biomphalaria glabrata embryonic) snail cell line resulted in increased or new expression of metabolically labeled polypeptides of approximately 21.5, 41, 70, and 74 kDa molecular mass. Regulation of this response appeared to be at the transcriptional level since a similar protein banding pattern was seen upon SDS-PAGE/fluorographic analysis of polypeptides produced by in vitro translation of total RNA from cells subjected to heat shock. Using a yeast (Saccharomyces cerevisiae) 70-kDa heat-shock protein (HSP70) probe to screen a cDNA library from heat-treated Bge cells, we isolated a full-length cDNA clone encoding a putative Bge HSP70. The cDNA was 2453 bp in length and contained an open reading frame of 1908 bp encoding a 636-amino-acid polypeptide with calculated molecular mass of 70,740 Da. Comparison of a conserved region of 209 amino acid residues revealed > 80% identity between the deduced amino acid sequence of Bge HSP70 and that of yeast (81%), the human blood fluke Schistosoma mansoni (for which B. glabrata serves as intermediate host) (81%), Drosophila (81%), human (84%), and the marine gastropod Aplysia californica (88%, 90%). In addition to the extensive sharing of sequence homology, the identification of several eukaryotic HSP70 signature sequences and an N-linked glycosylation site characteristic of cytoplasmic HSPs strongly support the identity of the Bge cDNA as encoding an authentic HSP70. Results of a Northern blot analysis, using Bge HSP70 clone-specific probes, indicated that gene expression was heat inducible and not constitutively expressed. This is the first reported sequence of an inducible HSP70 from cells originating from a freshwater gastropod and provides a first step in the development of a genetic transformation system for molluscs of medical importance. PMID- 9367733 TI - Programming the Drosophila embryo. AB - A critical step in understanding the mechanisms of development is in defining the steps at the molecular, cellular, and organismal levels in the developmental program for a given organism-so that given the egg one can predict not only how the embryo will develop but also how that embryo evolved from its ancestors. Using methods employed by chemists and engineers in modeling hierarchical systems, I have integrated current theory and experiment into a calculational method that can model early Drosophila embryogenesis on a personal computer. This quantitative calculation tool is simple enough to be useful for experimentalists in designing experiments yet detailed enough for theoreticians to derive new insights on the evolution of developmental genetic networks. By integrating the strengths of theoretical and experimental methods into a single engineering model that can compute the cascade of genetic networks in a real organism, I provide a new calculational tool that can apply current theory to current experimental data to study the evolution of developmental programs. PMID- 9367734 TI - Molecular complementarity I: the complementarity theory of the origin and evolution of life. AB - We assert that molecular complementarity is much more widespread than is commonly acknowledged in biological systems, if not actually ubiquitous. It creates the coupling necessary for non-equilibrium systems to form. It stabilizes aggregates against degradation, thereby increasing concentrations to levels adequate to foster the formation of prebiotic systems and represents the earliest form in which natural selection was manifested. Complementarity confers on all interacting parts of such systems in formation carrying capacity. RNA or DNA are not, therefore, necessary to the emergence of life, but represent specialized forms of complementary molecules adapted specifically to information storage and transmission. Non-genetic information exists in metabolic functions and probably preceded genetic information historically. Complementarity also provides the basis for homeostasis and buffering of such systems not only in a chemical, but also in structural and temporal terms. It provides a mechanism for understanding how new, emergent properties can arise, and a basis for the self-organization of systems. We demonstrate that such aggregates can have properties not predictable from their individual components, thus providing a means for understanding how new functions emerge during evolution. Selection is for modules rather than individual components. The formation of functional sub-systems that can then be integrated as modules greatly increases the probability of the emergence of life. The result of such modular evolution alters the standard view of evolution from a tree or bush-like image to an integrated network composed of alternating periods of integration (as molecules and molecular aggregates merge) and divergence (as molecules and aggregates undergo variations). This provides a mechanism for evolution by punctuated equilibria. Molecular complementarity puts strict limits on variations, however, preventing evolution from being random. The evolutionary, physiological and embryological consequences of this view of life are outlined, and various models and experiments described that further characterize it. PMID- 9367735 TI - Molecular complementarity II: energetic and vectorial basis of biological homeostasis and its implications for death. AB - The energetic basis of molecular complementarity is presented. In biological systems requiring both homeostasis and non-equilibrium state maintenance, molecular complementarity provides a framework for the co-existence of these states within an organism. Smoothly changing homeostatic and thermodynamic systems, such as regulation of pH or an ensemble of asynchronous muscle crossbridges, are modeled using Liapunov functions. When biological systems undergo discontinuous state changes, such as the initiation of the heartbeat, life/death transition or the detachment of molecules, alternative analytical systems such as catastrophe theory provide information that continuous analytical methods cannot. Catastrophe theory produces a model of biology in which death can occur by two distinct mechanisms: loss of homeostatic control or loss of sufficient free energy. Molecular complementarity buffers molecules from temporal and physical changes. The usefulness of molecular complementarity is limited to association energies near the ambient energy, kT. Within this range, complementarity will alter molecular functions and will convert scalar biochemical reactions into vectorial physiological processes. Both thermodynamic and catastrophic models can be used to link energetic and homeostatic processes: the former providing quantitative information from continuous systems; the latter providing qualitative information from discontinuous systems involving state changes. PMID- 9367736 TI - Acquired immunity on a schistosomiasis transmission model - fitting the data. AB - A semi-stochastic model is proposed to analyse the effects of acquired immunity on the transmission of schistosomiasis in the human host. The basic model's assumptions are as follows. The human host is assumed to build up an immune response after elapsing a fixed period of time L from the first infection. This acquired immunity is assumed to be partially effective and it is never lost. The parasite infection event is a Poisson process with multiple occurrences, i.e., in each event one or more cercaria are assumed to invade the host. The model treats deterministically the age distribution of human host. The model shows a good retrieving capacity of real data from two endemic areas of schistosomiasis: Touros, Brazil (Schistosoma mansoni) and Misungwi, Tanzania (Schistosoma haematobium). PMID- 9367737 TI - Non-independence in statistical tests for discrete cross-species data. AB - The paper described three previously undetected effects, due to biases and non independence, that can arise in statistical tests for associations between character states in cross-species data. One kind, which we call the family problem, is general to all known methods. In phytogenetic data, the ancestral character state from which changes occur, or below which variation is found, is likely to be the same for many regions of the tree. The family problem interacts with two kinds of non-independence that arise because of the methods of reconstruction of character states that existing tests use. Different kinds of non-independence arise in methods that reconstruct joint, or single, character states, respectively. Methods, like Ridley's (1983), that work with joint character states suffer from the problem that a character state cannot change to itself with parsimony. Other methods that work with single character states suffer from the problem that within a locally variable region of the tree it is more likely with null data that there will be two single changes in the two characters in separate branches than one double change in both; associations opposite to the locally ancestral state are therefore likely to be found in more than 50% of the variable regions. In real data sets, the family problem acts to spotlight the other kinds of bias: if the family problem is large the bias in tests due to the way they reconstruct characters will be large, whereas if it is small, the local biases tend to cancel and disappear in the aggregate. PMID- 9367738 TI - Sexual isolation in Drosophila. III. Estimating isolation using male-choice experiments. AB - It has been generally assumed that "choice experiments" are useful to measure sexual isolation between Drosophila strains or species. Theoretical models have demonstrated however that the results obtained using one of these designs, namely multiple-choice experiments, are insufficient to determine the degree of isolation, even under very favorable assumptions. In this work, a simple behavioral model is developed to test whether male-choice experiments can be used to measure sexual isolation in Drosophila. This model shows that, although the outcome of male-choice experiments is affected by differences in female receptivities, a procedure to estimate the minimum degree of isolation using this experimental design can be established. The application of the methods derived from the theoretical model to previously reported experimental data demonstrates that a substantial degree of isolation frequently exists intraspecifically, while isolation is far from complete interspecifically. These results have important implications for discussions based on the comparative analysis of Drosophila behavior, both intra- and interspecifically. Most especially, they are in contradiction with the expectations of the Recognition concept of species. PMID- 9367739 TI - A mutant form of mitochondrial GrpE suppresses the sorting defect caused by an alteration in the presequence of cytochrome b2. AB - Transport of preproteins across the inner mitochondrial membrane requires the action of the matrix heat shock protein Hsp70. Together with its co-chaperone mitochondrial GrpE (Mge1), mtHsp70 transiently binds to the inner membrane translocase subunit Tim44 in a nucleotide-regulated manner, forming an ATP dependent import driving machinery. We report that a mutant form of Mge1 (Mge1 100) is completely absent in mtHsp70-Tim44 complexes, although its ability to interact with soluble mtHsp70 is only partially reduced. While this mge1-100 mutation only partially retards preprotein translocation into the matrix, it exerts a selective effect on sorting of cytochrome b2 to the intermembrane space. A cytochrome b2 with an altered sorting signal, which is only processed to the intermediate stage and mistargeted to the matrix of wild-type mitochondria, is processed to the mature form and correctly targeted to the intermembrane space of mge1-100 mitochondria. These results suggest that (1) Mge1-100 discriminates between soluble and membrane-bound mtHsp70 and (2) the membrane-bound mtHsp70 Mge1 driving system competes with the sorting machinery for translocation of preproteins like cytochrome b2. PMID- 9367740 TI - Folding of RNA involves parallel pathways. AB - Folding kinetics of large RNAs are just beginning to be investigated. We show that the Tetrahymena self-splicing RNA partitions into a population that rapidly reaches the native state, and a slowly folding population that is trapped in metastable misfolded structures. Transitions from the misfolded structures to the native state involve partial unfolding. The total yield of native RNA is increased by iterative annealing of the inactive population, and mildly denaturing conditions increase the rate of folding at physiological temperatures. These results provide the first evidence that an RNA can fold by multiple parallel paths. PMID- 9367741 TI - Xenopus oocytes express a unitary glutamate receptor endogenously. AB - The results described here demonstrate that Xenopus oocytes endogenously express a unitary glutamate receptor subunit XenU1. The level of XenU1 mRNA expression reaches approximately 1/300 of that in the adult Xenopus brain. The endogenous expression of XenU1, which can functionally interact with N-methyl-D-aspartate receptor subunit NR1, explains the differences in NR1 subunit expression in mammalian cell lines (no functional expression without partner subunits) and in the Xenopus oocytes (NR1 forms functional receptors when expressed singly). PMID- 9367742 TI - Solution structure of the I gamma subdomain of the Mu end DNA-binding domain of phage Mu transposase. AB - The MuA transposase of phase Mu is a large modular protein that plays a central role in transposition. We show that the Mu end DNA-binding domain, I beta gamma, which is responsible for binding the DNA attachment sites at each end of the Mu genome, comprises two subdomains, I beta and I gamma, that are structurally autonomous and do not interact with each other in the absence of DNA. The solution structure of the I gamma subdomain has been determined by multidimensional NMR spectroscopy. The structure of I gamma comprises a four helix bundle and, despite the absence of any significant sequence identity, the topology of the first three helices is very similar to that of the homeodomain family of helix-turn-helix DNA-binding proteins. The helix-turn-helix motif of I gamma, however, differs from that of the homeodomains in so far as the loop is longer and the second helix is shorter, reminiscent of that in the POU-specific domain. PMID- 9367743 TI - Programmed cell death by hok/sok of plasmid R1: coupled nucleotide covariations reveal a phylogenetically conserved folding pathway in the hok family of mRNAs. AB - The hok/sok system of plasmid R1 mediates plasmid maintenance by killing of plasmid-free cells. Translation of the stable toxin-encoding hok mRNA is repressed by the unstable Sok antisense RNA. Using genetic algorithm simulations and phylogenetic comparisons, we analyse five plasmid-encoded and two chromosome encoded hok-homologous mRNAs. A similar folding pathway was found for all mRNAs. Metastable hairpins at the very 5'-ends of the mRNAs were predicted to prevent the formation of structures required for translation and antisense RNA binding. Thus the folding of the mRNA 5'-ends appears to explain the apparent inactivity of the nascent transcripts. In the full-length mRNAs, long-range 5' to 3' interactions were predicted in all cases. The 5' to 3' interactions lock the mRNAs in inactive configurations. Translation of the mRNAs is activated by 3' exonucleolytic processing. Simulation of the 3' processing predicted that it triggers rearrangements of the mRNA 5'-ends with the formation of translational activator and antisense RNA target hairpins. Alignment of the mRNA sequences revealed a large number of nucleotide covariations that support the existence of the proposed secondary structures. Furthermore, coupled covariations support the folding pathway and provide evidence that the mRNA 5'-ends pair with three different partners during the proposed series of dynamic RNA rearrangements. PMID- 9367744 TI - Programmed cell death by hok/sok of plasmid R1: processing at the hok mRNA 3'-end triggers structural rearrangements that allow translation and antisense RNA binding. AB - The hok/sok locus of plasmid R1 mediates plasmid stabilization by killing of plasmid-free cells. The locus specifies two RNAs, hok mRNA and Sok antisense RNA. The post-segregational killing mediated by hok/sok is governed by a complicated control mechanism that involves both post-transcriptional inhibition of translation by Sok-RNA and activation of hok translation by mRNA 3' processing. Sok-RNA inhibits translation of a reading frame (mok) that overlaps with hok, and translation of hok is coupled to translation of mok. In the inactive full-length hok mRNA, the translational activator element at the mRNA 5'-end (tac) is sequestered by the fold-back-inhibitory element located at the mRNA 3'-end (fbi). The 5' to 3' pairing locks the RNA in an inert configuration in which the SDmok and Sok-RNA target regions are sequestered. Here we show that the 3' processing leads to major structural rearrangements in the mRNA 5'-end. The structure of the refolded RNA explains activation of translation and antisense RNA binding. The refolded RNA contains an antisense RNA target stem-loop that presents the target nucleotides in a single-stranded conformation. The stem of the target hairpin contains SDmok and AUGmok in a paired configuration. Using toeprinting analysis, we show that this pairing keeps SDmok in an accessible configuration. Furthermore, a mutational analysis shows that an internal loop in the target stem is prerequisite for efficient translation and antisense RNA binding. PMID- 9367745 TI - Mapping of linear histone regions exposed at the surface of the nucleosome in solution. AB - Antibodies directed against defined regions of histone molecules represent one of the most specific probes for studying the topography and conformational changes of nucleosomes and chromatin. We have developed an assay involving a series of monoclonal and polyclonal antibody probes specifically reacting with a complete set of 40 overlapping synthetic peptides (6 to 28 residues long) covering the whole sequence of the four core histones H2A, H2B, H3 and H4. In this assay, mono , di- and trinucleosomes, as well as a long chain of chromatin containing 20 to 35 nucleosomes, were used in solution as competitors of the antibody reaction. At least 11 surface-oriented linear regions were characterized on the mononucleosome; namely, the N-terminal domains of H2A (residues 1 to 20), H2B (residues 1 to 25) and H3 (residues 1 to 30), the C-terminal domains of H2A (residues 116 to 129) and H4 (residues 85 to 102), and six domains located in internal segments in the primary structures of core histones (33 to 49 H2A, 65 to 85 H2A, 60 to 78 H2B, 50 to 70 H3, 111 to 130 H3 and 42 to 59 H4). Only a few changes in the nucleosome topography were observed when free oligo- and polynucleosome structure were comparatively studied. PMID- 9367746 TI - The GCN4 leucine zipper can functionally substitute for the heat shock transcription factor's trimerization domain. AB - The heat shock transcription factor (HSF) is the only known sequence-specific, homotrimeric DNA-binding protein. HSF binds to a DNA recognition site called a heat shock element (HSE), which contains varying numbers of nGAAn units ("GAA boxes") arranged in inverted repeats. To investigate the role of trimerization on HSF's DNA-binding properties, we replaced the trimerization domain, which self assembles to form a three-stranded alpha-helical coiled coil, with the GCN4 leucine zipper, which forms a two-stranded alpha-helical coiled coil. Surprisingly, this substitution did not effect the ability of HSF to function in vivo. Biochemical studies of an HSF-leucine zipper chimera in comparison to an HSF truncation show that the HSF-leucine zipper chimera, though dimeric in solution and dimeric when bound to a two-box HSE, forms a trimeric complex when bound to a three-box HSE. The ability to form trimers depends on the presence of three contiguous GAA boxes present in inverted repeats. The proximity of the leucine zippers due to the orientation of the binding sites suggests that the leucine zippers might be forming a three-stranded coiled coil and several experiments lend support to this model. The ability of the leucine zipper to change oligomeric states in context might explain why the leucine zipper can replace the trimerization domain of HSF in vivo. PMID- 9367747 TI - Role of DNA supercoiling and rpoS sigma factor in the osmotic and growth phase dependent induction of the gene osmE of Escherichia coli K12. AB - Transcription of the gene osmE of Escherichia coli is osmotically inducible and regulated by the growth phase. In a medium of low osmotic pressure, expression of osmE is induced at the onset of stationary phase. At elevated osmotic pressure, a biphasic induction pattern is observed. The first step occurs during exponential phase, and this is followed by a strong induction at the onset of stationary phase. Both steps appear to result from stimulation of transcription at the same promoter, osmEp. In the absence of sigma s, the stationary phase sigma factor encoded by rpoS, osmEp stationary phase induction is abolished, while the osmotic effect is still observed. Mutations that compensate for the absence of sigma s mapped to the gene topA. The effect of such mutation and of novobiocin, an inhibitor of DNA gyrase, suggest that changes in DNA supercoiling are involved in the osmotic induction of osmEp. In addition, modulation of the supercoiling level of a reporter plasmid was observed during growth in rich media. The kinetics of osmEp transcription are discussed in light of the variations of DNA supercoiling. PMID- 9367748 TI - Severe axial bending of RNA induced by the U1A binding element present in the 3' untranslated region of the U1A mRNA. AB - The 3' untranslated region of the U1A mRNA contains a binding site for the U1A protein that consists of two asymmetric internal bulges. The bulges each comprise a loop of seven unpaired bases opposing a single base (termed a U1A box). The seven-base loops are located on opposite strands, distributed in a symmetrical manner about the intervening four-base duplex. We have investigated the global conformation of this binding element. Comparison of electrophoretic mobilities of RNA duplexes interrupted by a single U1A box with a series of duplexes of the same length containing oligoadenine bulges indicates that the individual boxes cause a substantial kinking of the helix axis, estimated to be 90 (+/- 10) degrees. A series of RNA duplexes were constructed containing a U1A box separated from an A5 bulge by a duplex section of length between 3 and 21 bp. It was found that the electrophoretic mobilities of these species varied sinusoidally, indicating that the U1A box introduces a defined kink into the RNA helix, rather than a point of flexibility. Electrophoretic experiments with the complete U1A binding element suggest that the axial trajectories of the two U1A boxes combine to give an approximately in-line, 180 degrees change in duplex direction. PMID- 9367749 TI - Variation in HU composition during growth of Escherichia coli: the heterodimer is required for long term survival. AB - The histone-like dimeric HU protein of Escherichia coli is encoded by two closely related genes, hupA and hupB. We show here that expression from the single hupA promoter and from the three hupB promoters varies during growth phase. The weak hupB-P4 promoter is active immediately after dilution. Transcription of the hupA gene is activated early in logarithmic phase. A little later, at mid to late exponential phase, RNA originating at the hupB-P2 promoter is detected. The hupB P3 promoter is activated last when the cells enter stationary phase. Although the hup mRNAs are unstable, the HU protein is very stable so that the variations in the mRNAs synthesis are reflected in the level of the two HU subunits and in the composition of HU dimers. Cells growing exponentially contain a mixture of homodimeric alpha 2 and heterodimeric alpha beta but no beta 2 is detected. In stationary cells, the predominant form is the heterodimer alpha beta. The presence of the heterodimeric form is required for optimal survival of E. coli after prolonged starvation. The three forms of HU are not equivalent, since beta 2 is incapable of promoting formation of DNA supercoiling like alpha beta and alpha 2 do. The putative roles of each form of HU are discussed. PMID- 9367750 TI - (GT)n repetitive tracts affect several stages of RecA-promoted recombination. AB - The effect of GT/CA dinucleotide repeat tracts on RecA-dependent homologous recombination was examined in vitro. By measuring the binding of RecA protein to oligonucleotides containing GT or CA repeats using the surface plasmon resonance (BIAcore), we show that the efficiency of RecA protein binding is sequence dependent: the protein binds to non-repetitive, poly(CA) or poly(GT) sequences with an increasing affinity. This preferential binding to repetitive sequences is specific for RecA protein and is not observed with the single-strand DNA binding (SSB) protein. Despite the fact that RecA filaments formed on GT tracts efficiently bind duplex DNAs, they are unable to promote stable joint formation. Moreover, strand exchange between a duplex DNA and a fully homologous single stranded DNA (ssDNA) containing dinucleotide repeats, is inhibited as a function of the length of the repetitive tract. The number of molecules which underwent a complete strand exchange decreased from 100% to 80% and 30% for DNA containing seven, 16 and 39 GT repeats, respectively. The inhibition is less pronounced when the ssDNA contains CA instead of GT dinucleotide repeats. We propose that the high affinity of RecA protein for (CA)n or (GT)n tracts prevents strand exchange from progressing across such sequences. Thus, our results suggest that repetitive tracts of dinucleotides CA/GT could influence recombinational activity potentially leading to an increase in genomic rearrangements. PMID- 9367752 TI - HIV/SIV glycoproteins: structure-function relationships. AB - The various functions of human (HIV) and simian (SIV) immunodeficiency virus glycoproteins are similar, so it may be assumed that the overall structure of the folded proteins will be maintained. To preserve structure there must be constraints on sequence variation. The majority of mutations tolerated will be involved in immune escape but changes at some positions are known to have direct effects on glycoprotein expression and function. This allows the virus to change its phenotype and escape immune pressure. These properties will influence the fitness of the virus to infect and replicate in potential hosts. A better understanding of the structure-function relationships of HIV/SIV glycoproteins will assist in the development of vaccines and antivirals. Here, we identify similarities and differences between HIV-1 subtypes and HIV/SIV types that may be relevant to the phenotypes of the various groups. The results are discussed in relation to what is known of domain-function associations for HIV/SIV glycoproteins. PMID- 9367751 TI - Dual role for the yeast THI4 gene in thiamine biosynthesis and DNA damage tolerance. AB - The THI4 gene of Saccharomyces cerevisiae encodes an enzyme of the thiamine biosynthetic pathway. The plant homolog thi1, from Arabidopsis thaliana, is also involved in thiamine biosynthesis; but was originally cloned due to its capacity to complement DNA repair deficient phenotypes in Escherichia coli. Here, the behavior of a thi4 disrupted strain was examined for increased sensitivity to treatment with the DNA damaging agents ultraviolet radiation (UV, 254 nm) and methyl methanesulfonate (MMS). Although the thi4 null mutant showed a similar level of survival as the wild-type strain, a higher frequency of respiratory mutants was induced by the two treatments. A similar phenotype was seen with wild type strains expressing an antisense THI4 construct. Further analysis of respiratory mutants revealed that these were due to mutations of mitochondrial DNA (mtDNA) rather than nuclear DNA, consisting of rho-petite mutants. Moreover, the frequency of mutations was unaffected by the presence or absence of thiamine in the growth medium, and the defect leading to induction of petites in the thi4 mutant was corrected by expression of the Arabidopsis thi1 gene. Thus, Thi4 and its plant homolog appear to be dual functional proteins with roles in thiamine biosynthesis and mitochondrial DNA damage tolerance. PMID- 9367753 TI - 3-D image reconstruction of reconstituted smooth muscle thin filaments containing calponin: visualization of interactions between F-actin and calponin. AB - Calponin is a putative thin filament regulatory protein of smooth muscle that inhibits actomyosin ATPase in vitro. We have used electron microscopy and three dimensional reconstruction to elucidate the structural organization of calponin on actin and actin-tropomyosin filaments. Calponin density was clearly delineated in the reconstructions and found to occur peripherally along the long-pitch actin helix. The main calponin mass was located over sub-domain 2 of actin, and connected axially adjacent actin monomers by binding to the "upper" and "lower" edges of sub-domains 1 of each actin. When the reconstructions were fitted to the atomic model of F-actin, calponin appeared to contact actin near the N terminus and at residues 349 to 352 close to the C terminus of sub-domain 1 on one monomer. It also touched residues 92 to 95 of sub-domain 1 on the axially neighboring actin and continued up the side of this monomer as far as residues 43 to 48 of sub-domain 2. These positions are consensus binding sites for a number of actin-associated proteins and are also near to sites of weak myosin interaction. Calponin did not appear to block strong myosin binding sites on actin. In contrast to the calponin mass which appeared monomeric in reconstructions, tropomyosin formed a continuous strand of added density along F actin. When added to tropomyosin-containing filaments, calponin caused a shift of tropomyosin away from sub-domain 1 towards sub-domain 3 of actin, exposing strong myosin-binding sites that were previously covered by tropomyosin. This structural effect is unlike that of troponin and therefore inhibition of actomyosin ATPase by calponin and troponin cannot be strictly analogous. The location of calponin would allow it to directly compete or interact with a number of actin-binding proteins. PMID- 9367754 TI - Kinetic evidence for low chemical processivity in ncd and Eg5. AB - The kinesin molecular motor "walks" processively along microtubules, touching down with alternate motor domains and transiently bridging between sites spaced 8 nm apart axially. To allow bridging, the coiled coil tail of kinesin would need to unzip a region immediately adjacent to the heads, and the tail region sequence at this point indeed contains potentially destabilising interruptions in the regular hydrophobic heptad repeat. We noticed that such interruptions are substantially absent from the coiled coil tails of Eg5, a slow kinesin homologue, and ncd, a reverse-directed homologue, and we wondered if this precluded their processivity. We measured the temperature dependence of kcat/K50% MTs, an index of the chemical processivity of a motor, the number of ATPs split per productive diffusional encounter of motor with microtubule. We found two-headed ncd (GSTMC5) and two-headed Eg5 (E437GST) constructs to be slightly if at all processive in solution over the range 4 degrees C to 30 degrees C. By contrast, two-headed kinesin constructs K401 and K430 were processive, and became substantially more so with increasing temperature. Arrhenius plots for the solution ATPase were linear for all three motors. Arrhenius plots for MT gliding assays were linear and essentially parallel for E437GST and GSTMC5 (Ea = 61 and 63 kJ mol-1) but for K430 the plot was biphasic, with a break at 17 degrees C, corresponding to a 30% reduction in Ea from 84 to 57 kJ mol-1. The data indicate that ncd and Eg5 are only slightly if at all processive, and suggest that this may be related to structural differences in their coiled coil neck regions. PMID- 9367755 TI - The crystal structure of a parallel-stranded guanine tetraplex at 0.95 A resolution. AB - In both DNA and RNA, stretches of guanine bases can form stable four-stranded helices in the presence of sodium or potassium ions. Sequences with a propensity to form guanine tetraplexes have been found in chromosomal telomers, immunoglobulin switch regions, and recombination sites. We report the crystal structure at 0.95 A resolution of a parallel-stranded tetraplex formed by the hexanucleotide d(TG4T) in the presence of sodium ions. The four strands form a right-handed helix that is stabilized by hydrogen-bonding tetrads of co-planar guanine bases. Well-resolved sodium ions are found between and, at defined points, within tetrad planes and are coordinated with the guanine O6 groups. Nine calcium ions have been identified, each with a well-defined hepta-coordinate hydration shell. Hydrogen-bonding water patterns are observed within the tetraplex's helical grooves and clustered about the phosphate groups. Water molecules in the groove may form a hydrogen bond with the O4', and may affect the stacking behavior of guanine. Two distinct stacking arrangements are noted for the guanine tetrads. The thymine bases do not contribute to the four-stranded conformation, but instead stack to stabilize the crystal lattice. We present evidence that the sugar conformation is strained and propose that this originates from forces that optimize guanine base stacking. Discrete conformational disorder is observed at several places in the phosphodiester backbone, which results from a simple crankshaft rotation that requires no net change in the sugar conformation. PMID- 9367756 TI - Solution structure of the first three zinc fingers of TFIIIA bound to the cognate DNA sequence: determinants of affinity and sequence specificity. AB - The high resolution solution structure of a protein containing the three amino terminal zinc fingers of Xenopus laevis transcription factor IIIA (TFIIIA) bound to its cognate DNA duplex was determined by nuclear magnetic resonance spectroscopy. The protein, which is designated zf1-3, binds with all three fingers in the DNA major groove, with a number of amino acids making base specific contacts. The DNA structure is close to B-form. Although the mode of interaction of zf1-3 with DNA is similar to that of zif268 and other structurally characterized zinc finger complexes, the TFIIIA complex exhibits several novel features. Each zinc finger contacts four to five base-pairs and the repertoire of known base contact residues is extended to include a tryptophan at position +2 of the helix (finger 1) and arginine at position +10 (finger 3). Sequence-specific base contacts are made over virtually the entire length of the finger 3 helix. Lysine and histidine side-chains involved in base recognition are dynamically disordered in the solution structure; in the case of lysine, in particular, this could significantly decrease the entropic cost of DNA binding. The TGEKP(N) linker sequences, which are highly flexible in the unbound protein, adopt ordered conformations on DNA binding. The linkers appear to play an active structural role in stabilization of the protein-DNA complex. Substantial protein-protein contact surfaces are formed between adjacent fingers. As a consequence of these protein-protein interactions, the orientation of finger 1 in the major groove differs from that of the other fingers. Contributions to high affinity binding by zf1-3 come from both direct protein-DNA contacts and from indirect protein protein interactions associated with structural organization of the linkers and formation of well-packed interfaces between adjacent zinc fingers in the DNA complex. The structures provide a molecular level explanation for the large body of footprinting and mutagenesis data available for the TFIIIA-DNA complex. PMID- 9367757 TI - Conformational transitions and structural deformability of EcoRV endonuclease revealed by crystallographic analysis. AB - The structures of wild-type and mutant forms of the unliganded EcoRV endonuclease dimer have been determined at 2.4 A resolution in a new crystal lattice. Comparison of these structures with that of the free enzyme determined with different packing constraints shows that the conformations of the domain interfaces are not conserved between crystal forms. The unliganded enzyme and the enzyme-DNA complex delineate two distinct quaternary states separated by a 25 degrees intersubunit rotation, but considerable conformational heterogeneity, of the order of 10 degrees domain rotations, exists within each of these states. Comparison of the free enzyme structure between the two crystal forms further reveals that the C-terminal 28 amino acid residues are disordered and undergo an extensive local folding transition upon DNA binding. Introduction of the mutation T93A at the DNA-binding cleft causes large-scale effects on the protein conformation. Structural changes in the mutated unliganded enzyme propagate some 20 to 25 A to the dimerization interface and lead to a rearrangement of monomer subunits. Comparative analysis of these structures, a new structure of the enzyme cocrystallized with DNA and calcium ions, and previously determined cocrystal structures suggests important roles for a number of amino acid residues in facilitating the intersubunit motions and local folding transitions. In particular, the T93A structure reveals a pathway through the protein, by which DNA-binding may cause the domain movements required for proper alignment of catalytic groups. The key active-site residue Glu45 is located on a flexible helix inside this pathway, and this provides a direct means by which essential catalytic functions are coupled to the protein conformational change. It appears that indirect perturbation of the Glu45 conformation via an altered quaternary structure may be a contributing factor to the decreased catalytic efficiency of T93A, and this mechanism may also explain the diminished activities of other active site variants of EcoRV. PMID- 9367758 TI - The 1.6 A crystal structure of the AraC sugar-binding and dimerization domain complexed with D-fucose. AB - The crystal structure of the sugar-binding and dimerization domain of the Escherichia coli gene regulatory protein, AraC, has been determined in complex with the competitive inhibitor D-fucose at pH 5.5 to a resolution of 1.6 A. An in depth analysis shows that the structural basis for AraC carbohydrate specificity arises from the precise arrangement of hydrogen bond-forming protein side-chains around the bound sugar molecule. van der Waals interactions also contribute to the epimeric and anomeric selectivity of the protein. The methyl group of D fucose is accommodated by small side-chain movements in the sugar-binding site that result in a slight distortion in the positioning of the amino-terminal arm. A comparison of this structure with the 1.5 A structure of AraC complexed with L arabinose at neutral pH surprisingly revealed very small structural changes between the two complexes. Based on solution data, we suspect that the low pH used to crystallize the fucose complex affected the structure, and speculate about the nature of the changes between pH 5.5 and neutral pH and their implications for gene regulation by AraC. A comparison with the structurally unrelated E. coli periplasmic sugar-binding proteins reveals that conserved features of carbohydrate recognition are present, despite a complete lack of structural similarity between the two classes of proteins, suggesting convergent evolution of carbohydrate binding. PMID- 9367759 TI - Structural details of a calcium-induced molecular switch: X-ray crystallographic analysis of the calcium-saturated N-terminal domain of troponin C at 1.75 A resolution. AB - We have solved and refined the crystal and molecular structures of the calcium saturated N-terminal domain of troponin C (TnC) to 1.75 A resolution. This has allowed for the first detailed analysis of the calcium binding sites of this molecular switch in the calcium-loaded state. The results provide support for the proposed binding order and qualitatively, for the affinity of calcium in the two regulatory calcium binding sites. Based on a comparison with the high-resolution apo-form of TnC we propose a possible mechanism for the calcium-mediated exposure of a large hydrophobic surface that is central to the initiation of muscle contraction within the cell. PMID- 9367760 TI - Structure and mechanism of L-fucose isomerase from Escherichia coli. AB - The three-dimensional structure of L-fucose isomerase from Escherichia coli has been determined by X-ray crystallography at 2.5 A resolution. This ketol isomerase converts the aldose L-fucose into the corresponding ketose L-fuculose using Mn2+ as a cofactor. Being a hexamer with 64,976 Da per subunit, L-fucose isomerase is the largest structurally known ketol isomerase. The enzyme shows neither sequence nor structural similarity with other ketol isomerases. The hexamer obeys D3 symmetry and forms the crystallographic asymmetric unit. The strict and favorably oriented local symmetry allowed for a computational phase extension from 7.3 A to 2.5 A resolution. The structure was solved with an L fucitol molecule bound to the catalytic center such that the hydroxyl groups at positions 1 and 2 are ligands of the manganese ion. Most likely, L-fucitol mimics a bound L-fucose molecule in its open chain form. The protein environment suggests strongly that the reaction belongs to the ene-diol type. PMID- 9367761 TI - Crystal structure of the phosphatidylinositol-specific phospholipase C from the human pathogen Listeria monocytogenes. AB - The X-ray crystal structure of the phosphatidylinositol-specific phospholipase C (PI-PLC) from the human pathogen Listeria monocytogenes has been determined both in free form at 2.0 A resolution, and in complex with the competitive inhibitor myo-inositol at 2.6 A resolution. The structure was solved by a combination of molecular replacement using the structure of Bacillus cereus PI-PLC and single isomorphous replacement. The enzyme consists of a single (beta alpha)8-barrel domain with the active site located at the C-terminal side of the beta-barrel. Unlike other (beta alpha)8-barrels, the barrel in PI-PLC is open because it lacks hydrogen bonding interactions between beta-strands V and VI. myo-Inositol binds to the active site pocket by making specific hydrogen bonding interactions with a number of charged amino acid side-chains as well as a coplanar stacking interaction with a tyrosine residue. Despite a relatively low sequence identity of approximately 24%, the structure is highly homologous to that of B.cereus PI PLC with an r.m.s. deviation for 228 common C alpha positions of 1.46 A. Larger differences are found for loop regions that accommodate most of the numerous amino acid insertions and deletions. The active site pocket is also well conserved with only two amino acid replacements directly implicated in inositol binding. PMID- 9367762 TI - Torsion angle dynamics for NMR structure calculation with the new program DYANA. AB - The new program DYANA (DYnamics Algorithm for Nmr Applications) for efficient calculation of three-dimensional protein and nucleic acid structures from distance constraints and torsion angle constraints collected by nuclear magnetic resonance (NMR) experiments performs simulated annealing by molecular dynamics in torsion angle space and uses a fast recursive algorithm to integrate the equations of motions. Torsion angle dynamics can be more efficient than molecular dynamics in Cartesian coordinate space because of the reduced number of degrees of freedom and the concomitant absence of high-frequency bond and angle vibrations, which allows for the use of longer time-steps and/or higher temperatures in the structure calculation. It also represents a significant advance over the variable target function method in torsion angle space with the REDAC strategy used by the predecessor program DIANA. DYANA computation times per accepted conformer in the "bundle" used to represent the NMR structure compare favorably with those of other presently available structure calculation algorithms, and are of the order of 160 seconds for a protein of 165 amino acid residues when using a DEC Alpha 8400 5/300 computer. Test calculations starting from conformers with random torsion angle values further showed that DYANA is capable of efficient calculation of high-quality protein structures with up to 400 amino acid residues, and of nucleic acid structures. PMID- 9367764 TI - Complementation of peptide fragments of the single domain protein chymotrypsin inhibitor 2. AB - Chymotrypsin inhibitor 2 (CI2) folds kinetically as a single domain protein. It has been shown that elements of native secondary structure do not significantly form in fragments as the 64 residue protein is progressively increased in length from its N terminus, until at least 60 residues are present. Here, we analyse peptides of increasing length from the C terminus and find that native-like structure is not present even in the largest, fragment (7-64). We have examined sets of peptides of the form (1 - x) and ((x + 1)-64) to detect complementation. The only pair that readily complements and gives native-like structure is (1-40) and (41-64), where cleavage occurs in the protease-binding loop of CI2. But, all the pairs of peptides (1 - x) + (41-64) complement for x > 40, as do all pairs of (1-40) + (x-64), where x < 40. The resultant complexes appear to be equivalent to (1-40). (41-64) with the overlapping sequence being unstructured. Thus, the folding of CI2 is extremely co-operative, and interactions have to be made between subdomains (1-40) and (41-64). This is consistent with the mechanism proposed for the folding pathway of intact CI2 in which a diffuse nucleus is formed in the transition state between the alpha-helix in the N-terminal region of the protein and conserved hydrophobic contacts in the C-terminal region of the polypeptide. It is with these protein design features that CI2 can be an effective protease inhibitor. PMID- 9367763 TI - Structural and functional analyses of activating amino acid substitutions in the receiver domain of NtrC: evidence for an activating surface. AB - The bacterial enhancer-binding protein NtrC activates transcription when phosphorylated on aspartate 54 in its amino (N)-terminal regulatory domain or when altered by constitutively activating amino acid substitutions. The N terminal domain of NtrC, which acts positively on the remainder of the protein, is homologous to a large family of signal transduction domains called receiver domains. Phosphorylation of an aspartate residue in a receiver domain modulates the function of a downstream target, but the accompanying structural changes are not clear. In the present work we examine structural and functional differences between the wild-type receiver domain of NtrC and mutant forms carrying constitutively activating substitutions. Combinations of such substitutions resulted in both increased structural changes in the N-terminal domain, monitored by NMR chemical shift differences, and increased transcriptional activation by the full-length protein. Structural changes caused by substitutions outside the active site (D86N and A89T) were not only local but extended over a substantial portion of the N-terminal domain including the region from alpha-helix 3 to beta strand 5 ("3445 face") and propagating to the active site. Interestingly, the activating substitution of glutamate for aspartate at the site of phosphorylation (D54E) also triggered structural changes in the 3445 face. Thus, the active site and the 3445 face appear to interact. Implications with respect to how phosphorylation may affect the structure of receiver domains and how structural changes may be communicated to the remainder of NtrC are discussed. PMID- 9367765 TI - Glutamine, alanine or glycine repeats inserted into the loop of a protein have minimal effects on stability and folding rates. AB - Natural proteins can contain flexible regions in their polypeptide chain. We have investigated the effects of glycine, alanine and glutamine repeats on the stability and folding of a protein by inserting stretches of 7 to 13 residues into a suitable position in a model system, the chymotrypsin inhibitor-2 (CI2). This folds by residues (1-40) docking with residues (41-64) to form a folding nucleus. The peptides GQ4GM, GQ6GM, GQ8GM, GQ10GM, GA2SA4SA2GM and G3SG4SG3M were inserted after residue 40. The stability of the mutant proteins changes only weakly with chain length and nature of insertion, suggesting that the presence of unstructured polypeptide chains in a protein does not have a great energetic penalty. This has implications in catalysis, for example, where floppy regions have been noted in active sites, and in DNA transcription where activators, transcription factors and intermediary proteins all show long repeats of glycine/serine and/or glutamine, which are thought to be important for function. We find that the rate of folding is very insensitive to the length of the linker. The changes in rate are close to those predicted from polymer theory for the loss of configuration entropy on closing a loop. This implies that all the diffusion steps are relatively rapid. PMID- 9367766 TI - Visible volume: a robust measure for protein structure characterization. AB - We propose a new characterization of protein structure based on the natural tetrahedral geometry of the beta-carbon and a new geometric measure of structural similarity, called visible volume. In our model, the side-chains are replaced by an ideal tetrahedron, the orientation of which is fixed with respect to the backbone and corresponds to the preferred rotamer directions. Visible volume is a measure of the non-occluded empty space surrounding each residue position after the side-chains have been removed. It is a robust, parameter-free, locally computed quantity that accounts for many of the spatial constraints that are of relevance to the corresponding position in the native structure. When computing visible volume, we ignore the nature of both the residue observed at each side and the ones surrounding it. We focus instead on the space that, together, these residues could occupy. By doing so, we are able to quantify a new kind of invariance beyond the apparent variations within protein families, namely, the conservation of the physical space available at structurally equivalent positions for side-chain packing. Corresponding positions in native structures are likely to be of interest in protein structure prediction, protein design, and homology modeling. Visible volume is related to the degree of exposure of a residue position and to the actual rotamers in native proteins. Here, we discuss the properties of this new measure, namely, its robustness with respect to both crystallographic uncertainties and naturally occurring variations in atomic coordinates, and the remarkable fact that it is essentially independent of the choice of the parameters used in calculating it. We also show how visible volume can be used to align protein structures, to identify structurally equivalent positions that are conserved in a family of proteins, and to single out positions in a protein that are likely to be of biological interest. These properties qualify visible volume as a powerful tool in a variety of applications, from the detailed analysis of protein structure to homology modeling, protein structural alignment, and the definition of better scoring functions for threading purposes. PMID- 9367767 TI - Intermediate sequences increase the detection of homology between sequences. AB - Two homologous sequences, which have diverged beyond the point where their homology can be recognised by a simple direct comparison, can be related through a third sequence that is suitably intermediate between the two. High scores, for a sequence match between the first and third sequences and between the second and the third sequences, imply that the first and second sequences are related even though their own match score is low. We have tested the usefulness of this idea using a database that contains the sequences of 971 protein domains whose structures are known and whose residue identities with each other are some 40% or less (PDB40D). On the basis of sequence and structural information, 2143 pairs of these sequences are known to have an evolutionary relationship. FASTA, in an all against-all comparison of the sequences in the database, detected 320 (15%) of these relationships as well as three false positive (i.e. 1% error rate). Using intermediate sequences found by FASTA matches of PDB40D sequences to those in the large non-redundant OWL database we could detect 550 evolutionary relationships with an error rate of 1%. This means the intermediate sequence procedure increases the ability to recognise the evolutionary relationships amongst the PDB40D sequences by 70%. PMID- 9367768 TI - Do aligned sequences share the same fold? AB - Sequence comparison remains a powerful tool to assess the structural relatedness of two proteins. To develop a sensitive sequence-based procedure for fold recognition, we performed an exhaustive global alignment (with zero end gap penalties) between sequences of protein domains with known three-dimensional folds. The subset of 1.3 million alignments between sequences of structurally unrelated domains was used to derive a set of analytical functions that represent the probability of structural significance for any sequence alignment at a given sequence identity, sequence similarity and alignment score. Analysis of overlap between structurally significant and insignificant alignments shows that sequence identity and sequence similarity measures are poor indicators of structural relatedness in the "twilight zone", while the alignment score allows much better discrimination between alignments of structurally related and unrelated sequences for a wide variety of alignment settings. A fold recognition benchmark was used to compare eight different substitution matrices with eight sets of gap penalties. The best performing matrices were Gonnet and Blosum50 with normalized gap penalties of 2.4/0.15 and 2.0/0.15, respectively, while the positive matrices were the worst performers. The derived functions and parameters can be used for fold recognition via a multilink chain of probability weighted pairwise sequence alignments. PMID- 9367769 TI - Interaction of the bacteriophage Mu transcriptional activator protein, C, with its target site in the mom promoter. AB - The bacteriophage Mu C gene encodes a 16.5 kDa site-specific DNA binding protein that is a transcriptional activator of the four "late" promoters, Pmom, Plys, PI and PP. A symmetrical consensus C recognition sequence, TTAT[N5-6]ATAA, containing an inverted tetrad repeat separated by a spacer of five to six G+C rich nucleotides, has been proposed. To investigate this, we used oligonucleotide mutagenesis to introduce random substitutions within and flanking the proposed C target region; each variant site was tested for C recognition by an in vivo functional transactivation assay. We observed that all single mutations, in either tetrad, reduced C activation. Although two out of ten substitutions within the spacer reduced activation, the spacer region does not appear to make specific contact with C. We also used in vitro chemical-protection and -interference to study C contacts with Pmom. The results indicate that C contacts Pmom DNA on only one face of the helix through interactions within two adjacent major grooves; this conclusion was supported by gel shift analyses using synthetic oligonucleotide duplexes containing I.C or other base-pair substitutions. Evidence is also presented that C-Pmom contacts are asymmetrical, and that they extend two nucleotides 3' to the promoter-proximal tetrad. We also show that C binding induces a deformation, possibly a bend, in Pmom DNA. PMID- 9367770 TI - Identification of a minimal binding element within the T7 RNA polymerase promoter. AB - The T7 RNA polymerase promoter has been proposed to contain two domains: the binding region upstream of position -5 is recognized through apparently traditional duplex contacts, while the catalytic domain downstream of position -5 is bound in a melted configuration. This model is tested by following polymerase binding to a series of synthetic oligonucleotides representing truncations of the consensus promoter sequence. The increase in the fluorescence anisotropy of a rhodamine dye linked to the upstream end of the promoter provides a very sensitive measure of enzyme binding in simple thermodynamic titrations, and allows the determination of both increases and decreases in the dissociation constant. The best fit value of Kd=4.0 nM for the native promoter is in good agreement with previous fluorescence and steady state measurements. Deletion of the downstream DNA up to position -1 or to position -5 leads to a fivefold increase in binding, while further sequential single-base deletions upstream result in 20 and 500-fold decreases in binding. These results indicate that the (duplex) region of the promoter upstream of and including position -5 is both necessary and sufficient for tight binding, and represents the core binding element of the promoter. We propose a model in which part of the upstream binding energy is used by T7 RNA polymerase to melt the downstream initiation region of the promoter. We also show that the presence of magnesium is necessary for optimal binding, but not for specific enzyme-promoter complex formation, and we propose that magnesium is not required for melting of the promoter. PMID- 9367771 TI - Interdependence in the processing of ribosomal RNAs in Schizosaccharomyces pombe. AB - Eukaryotic rRNAs are produced by cleavage of a large 35 to 45 S pre-rRNA transcript which initially must be fully transcribed and assembled into an 80 to 90 S nucleolar ribonucleoprotein particle. Despite this need for a completed transcript, several investigations have reported a split processing scheme for independent maturation of the large and small subunit rRNAs. Here, an efficiently expressed rDNA plasmid was used to quantitatively analyze the effects of mutations in the internal transcribed spacer (ITS) region in the yeast, Schizosaccharomyces pombe. The results show that substitution of ITS regions inhibits the processing of distant external transcribed spacers (ETS) and that deletion of the ITS2 spacer not only prevents the maturation of the large subunit, but severely affects maturation of the small subunit rRNA. This indicates that the processing mechanisms are not fully split and, when taken together with other evidence of interdependences in rRNA maturation, the results suggest that the interdependences act as a quality control mechanism to help ensure that only functional rRNA is incorporated into ribosomes. PMID- 9367772 TI - De novo protein design: towards fully automated sequence selection. AB - Several groups have applied and experimentally tested systematic, quantitative methods to protein design with the goal of developing general design algorithms. We have sought to expand the range of computational protein design by developing quantitative design methods for residues of all parts of a protein: the buried core, the solvent exposed surface, and the boundary between core and surface. Our goal is an objective, quantitative design algorithm that is based on the physical properties that determine protein structure and stability and which is not limited to specific folds or motifs. We chose the betabetaalpha motif typified by the zinc finger DNA binding module to test our design methodology. Using previously published sequence scoring functions developed with a combined experimental and computational approach and the Dead-End Elimination theorem to search for the optimal sequence, we designed 20 out of 28 positions in the test motif. The resulting sequence has less than 40% homology to any known sequence and does not contain any metal binding sites or cysteine residues. The resulting peptide, pda8d, is highly soluble and monomeric and circular dichroism measurements showed it to be folded with a weakly cooperative thermal unfolding transition. The NMR solution structure of pda8d was solved and shows that it is well-defined with a backbone ensemble rms deviation of 0. 55 A. Pda8d folds into the desired betabetaalpha motif with well-defined elements of secondary structure and tertiary organization. Superposition of the pda8d backbone to the design target is excellent, with an atomic rms deviation of 1.04 A. PMID- 9367773 TI - Regulation of the elongation-termination decision at intrinsic terminators by antitermination protein N of phage lambda. AB - The mechanisms that control N-protein-dependent antitermination in the phage lambda life cycle have counterparts in the regulatory systems of other organisms. Here we examine N-dependent antitermination at the intrinsic tR' terminator of lambda to elucidate the regulatory principles involved. The tR' terminator consists of a sequence of six base-pairs along the template at which the transcription complex is sufficiently destabilized to make RNA release possible. Within this "zone of opportunity" for termination the termination efficiency (TE) at each template position is determined by a kinetic competition between alternative reaction pathways that lead either to elongation or to termination. TE values at each position within tR' have been mapped as a function of NTP concentration, and it is shown that N protein (in the presence of NusA and a nut site; the minimal system for N-dependent antitermination) can offset increases in TE that are induced by limiting the concentrations of each of the next required NTPs. By limiting NTP concentrations or working at low temperature we show that a significant effect of N within the minimal system is to increase the rate of transcript elongation three- to fivefold at most positions along the template. Assuming that a comparable increase in elongation rate applies at template positions within the terminator, we show that an increase of this magnitude is not sufficient to account for the antitermination efficiency observed and that an approximately 100-fold stabilization of the transcription complex at intrinsic termination sites as a consequence of binding the N-containing antitermination sub-assembly must be invoked as well. A general method for partitioning TE effects in antitermination between changes in elongation rate and termination complex stability is demonstrated, based on competing free energy of activation barriers for the elongation and termination reactions. The analysis and utility of such mixed modes of transcriptional regulation are considered in general terms. PMID- 9367774 TI - Possible mechanisms for the regulation of telomere length. AB - Since DNA polymerases can only synthesise a new DNA strand in the 5'-3' direction and need a primer that provides a free 3' OH end, the cellular replication machinery is unable to duplicate the 3' ends of linear chromosomes unless special mechanisms are operative. While the telomeres seem to shorten continuously in human somatic cells because of the "end replication" problem, it appears that telomere length is maintained in cancer cells, the germ line and unicellular organisms like yeast and Tetrahymena by a mechanism involving the enzyme telomerase, which elongates the 3' ends of telomeres. However, telomerase must be part of a more complicated mechanism to ensure that there is no net gain or loss of telomeric ends. Here we describe a simple theoretical model that can explain several experimental findings. The simulations show that (i) the proposed mechanism is able to maintain telomeres at a constant length, (ii) this length constancy is independent of the initial telomere length, (iii) mutations of the telomeric sequence lead to an elongation of telomeres, (iv) inhibition of telomerase causes telomeric shortening, and (v) it reproduces and explains the experimental result that the addition of oligonucleotides to the culture medium leads to an increase of telomere length. PMID- 9367775 TI - The interaction of the F plasmid killer protein, CcdB, with DNA gyrase: induction of DNA cleavage and blocking of transcription. AB - We have studied the interaction of the F plasmid killer protein CcdB with its intracellular target DNA gyrase. We confirm that CcdB can induce DNA cleavage by gyrase and show that this cleavage reaction requires ATP hydrolysis when the substrate is linear DNA, but is independent of hydrolysis when negatively supercoiled DNA is used. The 64 kDa domain of the gyrase A protein, which can catalyse DNA cleavage in the presence of the B protein and quinolone drugs, is unable to cleave DNA in the presence of CcdB unless the C-terminal 33 kDa domain of the gyrase A protein is also present. CcdB-induced DNA cleavage by gyrase requires a minimum length of DNA (> approximately 160 bp), whereas in the presence of quinolone drugs gyrase can cleave much shorter DNA molecules. We show that CcdB, like quinolones, can form a complex with gyrase which can block transcription by RNA polymerase. A model for the interaction of CcdB with gyrase involving the trapping of a post-strand-passage intermediate is suggested. We conclude that CcdB can stabilise a cleavage complex between DNA gyrase and DNA in a manner distinct from quinolones but, like the quinolone-induced cleavage complex, the CcdB-stabilised complex can also form a barrier to the passage of polymerases. PMID- 9367776 TI - Centromeric pyrimidine strands fold into an intercalated motif by forming a double hairpin with a novel T:G:G:T tetrad: solution structure of the d(TCCCGTTTCCA) dimer. AB - The solution structures of the oligodeoxynucleotides d(CCCGTTTCC) and d(TCCCGTTTCCA) have been determined by two-dimensional NMR spectroscopy. These oligomers are part of a DNA box in human centromeric alpha satellite targeted by the centromere protein B (CENP-B). Both CENP-B and its recognition box in alphoid DNA are conserved in mammals, suggesting an important biological role. At acidic pH, d(CCCGTTTCC), d(TCCCGTTTCCA) and the full d(TCCCGTTTCCAACGAAG) CENP-B box strand all fold and dimerize in solution forming a stable bimolecular structure containing two GTTT hairpin loops that interact through a novel T : G : G : T tetrad. The stem region of the dimer is a four-stranded intercalated motif in which the hairpin monomers are parallel and held together by C : C+ hydrogen bonding and intercalation. The loops are at the same end of the dimer and lie across the narrow grooves of the tetraplex. They are remarkably structured and stabilized by base-base cross-stacking, sugar-base stacking, and parallel G:G and antiparallel G:T pairing. In the d(TCCCGTTTCCA)2 structure, the intercalated motif is continued at the other end of the dimer with unpaired but stacked adenine and thymine bases. The possible biological implications of these structures are discussed. PMID- 9367777 TI - Crystallization, structural determination and analysis of a novel parasite vaccine candidate: Fasciola hepatica glutathione S-transferase. AB - Glutathione S-transferases (GSTs) represent the major class of detoxifying enzymes from parasitic helminths. As a result, they are candidates for chemotherapeutic and vaccine design. Indeed, GSTs from Fasciola hepatica have been found to be effective for vaccinating sheep and cattle against fasciolosis. This helminth contains at least seven GST isoforms, of which four have been cloned. The cloned isoforms (Fh51, Fh47, Fh7 and Fh1) all belong to the mu class of GSTs, share greater than 71% sequence identity, yet display distinct substrate specificities. Crystals of Fh47 were obtained using the hanging drop vapour diffusion technique. The crystals belong to space group I4122, with one monomer in the asymmetric unit, which corresponds to a very high solvent content of approximately 75%. The physiological dimer is generated via a crystallographic 2 fold rotation. The three-dimensional structure of Fh47 was solved by molecular replacement using the Schistosoma japonicum glutathione S-transferase (Sj26) crystal structure as a search model. The structure adopts the canonical GST fold comprising two domains: an N-terminal glutathione-binding domain, consisting of a four-stranded beta-sheet and three helices whilst the C-terminal domain is entirely alpha-helical. The presence of Phe19 in Fh47 results in a 6 degrees interdomain rotation in comparison to Sj26, where the equivalent residue is a leucine. Homology models of Fh51, Fh7 and Fh1, based on the Fh47 crystal structure, reveal critical differences in the residues lining the xenobiotic binding site, particularly at residue positions 9, 106 and 204. In addition, differences amongst the isoforms in the non-substrate binding site were noted, which may explain the observed differential binding of large ligands. The major immunogenic epitopes of Fh47 were surprisingly found not to reside on the most solvent-exposed regions of the molecule. PMID- 9367778 TI - In vitro structure-function analysis of the beta-strand 326-333 of human p53. AB - The beta-strand 326-333 is a key structural element in the formation of p53 tetramers. To investigate the contribution of its amino acid residues, an alanine scan was performed. The oligomerisation and DNA-binding properties of the mutant proteins were compared with those of wild-type proteins in vitro and analysed on the basis of the crystal structure of the p53 tetramerisation domain at 1.5 A resolution. Two categories of mutant proteins were identified. Phe328Ala, Leu330Ala and Ile332Ala mutant proteins are inactive for DNA binding and oligomerisation, while the Glu326Ala, Tyr327Ala, Thr329Ala, Gln331Ala and Arg333Ala mutant proteins have properties similar to those of wild-type proteins. These results suggest that single mutations within the p53 tetramerisation domain destabilise the structure of the whole protein, inhibiting its DNA-binding activity. Furthermore, the mutation of leucine 330 to alanine within the tetramerisation domain of the Arg175His protein abolishes the dominant negative effect of this mutant. This shows that the beta-strand 326-333 is a key structural element that mediates the dominant negative effect of p53 mutants. PMID- 9367780 TI - Role of beta-turn residues in beta-hairpin formation and stability in designed peptides. AB - The sequence RGITVNGKTYGR has been reported as part of a de novo design peptide system. This peptide folds as a beta-hairpin structure with three residues per strand and two residue turns. Asn6 side-chain, the residue in position L1 of the beta-turn, appeared to be solvent exposed, interacting only within the turn but not with the rest of the peptide. We have chosen this position as a good candidate to design mutations, based on the protein database statistical abundances, that should mainly affect the turn stability and possibly the pairing between strands. We have found that all NMR parameters, in particular the conformational shift analysis of CalphaH and the coupling constants, 3JHNalpha, correlate very well and show similar conformational features in all the turn mutant peptides. The population estimates are in reasonable agreement among the different methods used. It appears that the peptide with Asn in position L1 is the most structured peptide, followed by the one with Asp6. The next structured peptide is the one with Gly6. The least populated peptides were those with Ala6 and Ser6. We have found a strong correlation between the hairpin population, as determined from the conformational shift of CalphaH and the occurrence of the different residues at position L1 of beta-hairpins with type I' beta-turn, in the protein database. Our analysis demonstrates that this peptide system is sensitive enough to register small energy changes in the hairpin structure; therefore, it constitutes an appropriate model to quantify energy contributions, once the appropriate sheet/coil transition algorithm is developed. Comparison with the other studies indicate that the design of a specific hairpin structure must involve a sequence at the turn region favouring the desired turn type, and a sequence at the strands that avoids alternative interstrand side-chain pairings. PMID- 9367779 TI - Neutralizing epitopes on the extracellular interferon gamma receptor (IFNgammaR) alpha-chain characterized by homolog scanning mutagenesis and X-ray crystal structure of the A6 fab-IFNgammaR1-108 complex. AB - The extracellular interferon gamma receptor alpha-chain comprises two immunoglobulin-like domains, each with fibronectin type-III topology, which are responsible for binding interferon gamma at the cell surface. The epitopes on the human receptor recognized by three neutralizing antibodies, A6, gammaR38 and gammaR99, have been mapped by homolog scanning mutagenesis. In this way, a loop connecting beta-strands C and C' in the N-terminal domain was identified as a key component of the epitopes bound by A6 and gammaR38, whereas gammaR99 binds to the C-terminal domain in a region including strands A and B and part of the large C'E loop. The epitope for A6 was confirmed in a crystal structure of a complex between a recombinant N-terminal receptor domain and the Fab fragment from A6, determined by X-ray diffraction to 2.8 A resolution. The antibody-antigen interface buries 1662 A2 of protein surface, including 22 antibody residues from five complementarity determining regions, primarily through interactions with the CC' surface loop of the receptor. The floor of the antigen binding cavity is formed mainly by residues from CDR L3 and CDR H3 while a surrounding ridge is formed by residues from all other CDRs except L2. Many potential polar interactions, as well as 13 aromatic side-chains, four in VL, six in VH and three in the receptor, are situated at the interface. The surface of the receptor contacted by A6 overlaps to a large extent with that contacted by interferon gamma, in the ligand-receptor complex. However, the conformation of this epitope is very different in the two complexes, demonstrating that conformational mobility in a surface loop on this cytokine receptor permits steric and electrostatic complementarity to two quite differently shaped binding sites. PMID- 9367781 TI - Structure of the fifth EGF-like domain of thrombomodulin: An EGF-like domain with a novel disulfide-bonding pattern. AB - The structure of the fifth EGF-like domain (residues Q387 to E426) of thrombomodulin (TMEGF5) has been determined by two-dimensional NMR. TMEGF5 binds to thrombin with a Ki of 1.9 microM and has been shown to have a novel disulfide bonding pattern in a fully active fragment of TM. In EGF, the disulfide bonding pattern is (1-3,2-4, 5-6), while TMEGF5 has an uncrossed (1-2,3-4,5-6) pattern. The structure of this novel domain, determined from 483 NOE-derived distance restraints, appears to have diverged from the common EGF-like structure. Superposition of the 14 lowest-energy structures of TMEGF5 gives an overall r.m.s.d. of 1.09 A for the backbone atoms. The central two-stranded beta-sheet common to all EGF-like domains is not present in TMEGF5. The A loop, residues C390 to C395, is twisted away from interacting with the B loop, residues C399 to C407, as in EGF, and is close to the C loop, residues C409 to C421. This twist causes the N and C termini to be closer together in TMEGF5 than in EGF. Most of the residues that are important for activity lie on one face of the molecule, which is likely to be the thrombin-binding surface of the domain. The structure of the C loop within the domain, which is a beta-hairpin similar to EGF, is similar to the structure of a synthetic version of the loop bound to thrombin as determined by transferred NOE experiments. Despite the similarity in the structures of the loops, the residues immediately following C421 are in different positions in the two structures suggesting that these "tail" residues may change conformation upon thrombin binding. PMID- 9367782 TI - Standard conformations for the canonical structures of immunoglobulins. AB - A comparative analysis of the main-chain conformation of the L1, L2, L3, H1 and H2 hypervariable regions in 17 immunoglobulin structures that have been accurately determined at high resolution is described. This involves 79 hypervariable regions in all. We also analysed a part of the H3 region in 12 of the 15 VH domains considered here. On the basis of the residues at key sites the 79 hypervariable regions can be assigned to one of 18 different canonical structures. We show that 71 of these hypervariable regions have a conformation that is very close to what can be defined as a "standard" conformation of each canonical structure. These standard conformations are described in detail. The other eight hypervariable regions have small deviations from the standard conformations that, in six cases, involve only the rotation of a single peptide group. Most H3 hypervariable regions have the same conformation in the part that is close to the framework and the details of this conformation are also described here. PMID- 9367783 TI - Transient channel-opening in bacteriorhodopsin: an EPR study. AB - Active translocation of ions across membranes requires alternating access of the ion binding site inside the pump to the two membrane surfaces. Proton translocation by bacteriorhodopsin (bR), the light-driven proton pump in Halobacterium salinarium, involves this kind of a change in the accessibility of the centrally located retinal Schiff base. This key event in bR's photocycle ensures that proton release occurs to the extracellular side and proton uptake from the cytoplasmic side. To study the role of protein conformational changes in this reprotonation switch, spin labels were attached to pairs of engineered cysteine residues in the cytoplasmic interhelical loops of bR. Light-induced changes in the distance between a spin label on the EF interhelical loop and a label on either the AB or the CD interhelical loop were observed, and the changes were monitored following photoactivation with time-resolved electron paramagnetic resonance (EPR) spectroscopy. Both distances increase transiently by about 5 A during the photocycle. This opening occurs between proton release and uptake, and may be the conformational switch that changes the accessibility of the retinal Schiff base to the cytoplasmic surface after proton release to the extracellular side. PMID- 9367784 TI - Role of open complex instability in kinetic promoter selection by bacteriophage T7 RNA polymerase. AB - By measuring steady-state rates of dinucleotide synthesis on double-stranded (d.s.) and partially single-stranded (p.s.s.) promoters, and topological unwinding due to open complex formation on plasmids, we have obtained evidence that open complex formation in bacteriophage T7 RNA polymerase:promoter binary complexes is thermodynamically disfavored and that the rate of collapse of the open complex is competitive with the rate of transcription initiation. It is suggested that open complex instability is a kinetic mechanism that allows T7 RNA polymerase (RNAP) to achieve promoter specificity while still allowing for efficient promoter release. Open complex instability could also provide a mechanism for modulating the KM for the initiating NTPs so as to allow different promoters to respond differently to physiological changes in NTP concentration. PMID- 9367785 TI - Structural alterations far from the anticodon of the tRNAProGGG of Salmonella typhimurium induce +1 frameshifting at the peptidyl-site. AB - A total of 12 Salmonella typhimurium mutants were selected with mutations in the minor tRNAProGGG which suppress a +1 frameshift mutation in the hisD gene. This tRNA normally has 1-methylguanosine (m1G37) next to and 3' of the anticodon (position 37). Since the presence of m1G37 prevents frameshifting, some of the +1 frameshift suppressor derivatives of tRNAProGGG had alterations in the primary sequence abolishing the formation of m1G37. However, several of the mutant tRNAProGGG species had a normal level of m1G37 and a normal-sized anticodon loop, showing that neither m1G37 deficiency, nor an oversized anticodon loop, is a prerequisite for +1 frameshifting. Moreover, base substitutions far from the anticodon, e.g. in the acceptor stem, DHU-loop and stem, and at the top of the anticodon stem, promoted +1 frameshifting. When the frameshifting site (CCC-Uaa; CCC is in the zero frame and a +1 frameshift moves the ribosome to the CC-U codon) is overlapped by a nonsense codon (UAA), the efficiency of frameshifting decreased when release factor 1 was over-expressed and increased at an elevated temperature in a mutant with a temperature-sensitive release factor 1. The frameshifting site (CCC-Uac) was also overlapped with the sense codon UAC, which is decoded by a tRNA species having a 2-methylthio-cis ribozeatin (ms2io6A) at position 37. Mutations in the miaA gene affect the formation of this modified nucleoside and result in an A instead of ms2io6A37 in the tRNA. Such an undermodified tRNA is very inefficient in translation and the efficiency of frameshifting increased in a miaA1 mutant. These results suggest that the frameshifting event occurs at the P-site, since the efficiency of frameshifting was sensitive to the decoding activity of the overlapping codon. We conclude that tRNA with mutations far from the anticodon, with a normal-sized anticodon loop and having m1G37 induce +1 frameshifting at the P-site. PMID- 9367787 TI - Assessment of the aggregation state of integral membrane proteins in reconstituted phospholipid vesicles using small angle neutron scattering. AB - The assessment of the physical size of integral membrane protein complexes has generally been limited to samples solubilized in non-ionic detergent, a process which may introduce artifacts of unknown scope and severity. A system has been developed that allows observation of the small angle scattering profile of an integral membrane protein while incorporated in small unilamellar phospholipid vesicles. Contrast matching of isotopically substituted phospholipid eliminates the contribution of the bilayer to the observed scattering, resulting in a profile dependent only on the structure of the individual membrane protein complexes and their spatial arrangement in the vesicle. After appropriate compensation for their spatial arrangement, information about the molecular mass and radius of gyration of the individual complexes can be obtained. The validity of the approach has been established using monomeric bacteriorhodopsin as a model system. PMID- 9367786 TI - MPc2, a new murine homolog of the Drosophila polycomb protein is a member of the mouse polycomb transcriptional repressor complex. AB - The evolutionarily conserved polycomb and trithorax-group genes are required to maintain stable expression patterns of homeotic genes and other target genes throughout development. Here, we report the cloning and characterization of a novel mouse polycomb homolog, MPc2, in addition to the previously described M33 polycomb gene. Co-immunoprecipitations and subnuclear co-localization studies show that MPc2 interacts with the mouse polycomb-group oncoprotein Bmi1 and is a new member of the mouse polycomb multiprotein complex. Gal4DB-MPc2 or -M33 fusion proteins mediate a five- to tenfold repression of stably integrated reporter constructs carrying GAL4 binding sites, demonstrating that these proteins are transcriptional repressors. The MPc2 gene is localized on chromosome 11, in close proximity to the classical mouse mutations tail short (Ts) and rabo torcido (Rbt). Ts and Rbt hemizygous mice display anemia and transformations of the axial skeleton reminiscent of phenotypes observed in mice with mutated polycomb or trithorax-group genes, suggesting that MPc2 is a candidate gene for Ts and Rbt. PMID- 9367788 TI - Affinities and selectivities of divalent cation binding sites within an RNA tertiary structure. AB - A 58 nucleotide fragment of Escherichia coli large subunit ribosomal RNA, nucleotides 1051 to 1108, adopts a specific tertiary structure normally requiring both monovalent (NH4+ or K+) and divalent (Mg2+) ions to fold; this ion-dependent structure is a prerequisite for recognition by ribosomal protein L11. Melting experiments have been used to show that a sequence variant of this fragment, GACG RNA, is able to adopt a stable tertiary structure in the presence of 1.6 M NH4Cl and absence of divalent ions. The similarity of this high-salt structure to the tertiary structure formed under more typical salt conditions (0.1 M NH4Cl and several mM MgCl2) was shown by its following properties: (i) an unusual ratio of hyperchromicity at 260 nm and 280 nm upon unfolding, (ii) selectivity for NH4+ over K+ or Na+, (iii) stabilization by L11 protein, and (iv) further stabilization by added Mg2+. Delocalized electrostatic interactions of divalent ions with nucleic acids should be very weak in the presence of >1 M monovalent salt; thus stabilization of the tertiary structure by low (<1 mM) Mg2+ concentrations in these high-salt conditions suggests that Mg2+ binds at specific site(s). GACG RNA tertiary structure unfolding in 1.6 M NH4Cl (Tm approximately 39 degrees C) is distinct from melting of the secondary structure (centered at approximately 72 degrees C), and it has been possible to calculate the free energy of tertiary structure stabilization upon addition of various divalent cations. From these binding free energies, ion-RNA binding isotherms for Mn2+, Mg2+, Ca2+, Sr2+ and Ba2+ have been obtained. All of these ions bind at two sites: one site favors Mg2+ and Ba2+ and discriminates against Ca2+, while the other site favors binding of smaller ions over larger ones (Mg2+ >Ca2+ >Sr2+ >Ba2+). Weak cooperative or anticooperative interactions between the sites, also dependent on ion radius, may also be taking place. PMID- 9367789 TI - Refined X-ray crystallographic structure of the poliovirus 3C gene product. AB - The X-ray crystallographic structure of the recombinant poliovirus 3C gene product (Mahoney strain) has been determined by single isomorphous replacement and non-crystallographic symmetry averaging and refined at 2.1 A resolution. Poliovirus 3C is comprised of two six-stranded antiparallel beta-barrel domains and is structurally similar to the chymotrypsin-like serine proteinases. The shallow active site cleft is located at the junction of the two beta-barrel domains and contains a His40, Glu71, Cys147 catalytic triad. The polypeptide loop preceding Cys147 is flexible and likely undergoes a conformational change upon substrate binding. The specificity pockets for poliovirus 3C are well-defined and modeling studies account for the known substrate specificity of this proteinase. Poliovirus 3C also participates in the formation of the viral replicative initiation complex where it specifically recognizes and binds the RNA stem-loop structure in the 5' non-translated region of its own genome. The RNA recognition site of 3C is located on the opposite side of the molecule in relation to its proteolytic active site and is centered about the conserved KFRDIR sequence of the domain linker. The recognition site is well-defined and also includes residues from the amino and carboxy-terminal helices. The two molecules in the asymmetric unit are related by an approximate 2-fold, non-crystallographic symmetry and form an intermolecular antiparallel beta-sheet at their interface. PMID- 9367790 TI - The entropy cost of protein association. AB - The temperature induced unfolding/dissociation of the dimeric subtilisin inhibitor from Streptomyces and its mutant D83C having an S-S crosslink between the subunits has been studied calorimetrically. Comparison of the entropies measured at different concentrations of dimer showed that the entropy cost of crosslinking is small. Its value at the standard concentration of 1 M is of the order of -(5+/-4) cal/K.mol, i.e. it is more than one order of magnitude smaller than the values of translational entropies calculated on the base of statistical thermodynamics, using in particular the Sackur-Tetrode equation, and is close to the cratic entropy value suggested by classical mixing theory. PMID- 9367791 TI - Editorial PMID- 9367792 TI - The old and the new in p53 functional regulation. AB - The gene termed p53 is one of the most extensively studied for the past 18 years and the amount of literature published on this gene reflects its relevance in the field of molecular oncology; thus, loss or mutation of this oncosuppressor gene is probably the molecular lesion most frequently observed in human tumors. The aim of this minireview is to report, discuss, and interpret some recent observations on this topic: (I) The relationship with the Ataxia-Telangectasia gene and with the signaling enzyme phosphatidylinositol 3-kinase (PI3K). (II) The relationship between DNA damage, p53, and sensitivity to anticancer therapies. (III) The gain of function caused by mutations that transform the oncosuppressor p53 gene into a dominant transforming oncogene and (IV) The phosphorylative regulation of p53 and its relationship with the mitogenic signaling cascade involving protein kinase C and tumor promoters. PMID- 9367793 TI - Therapeutic potential and mechanism of action of oligonucleotides and ribozymes. AB - Specific inactivation of gene expression is an attractive approach for rational drug design to combat degenerative diseases and infectious agents. Oligonucleotide-directed triple-helix formation at cis-acting elements of gene promoters, short oligonucleotides containing base sequences that are complementary to the messenger RNA (antisense oligos), and RNA enzymes (ribozymes) that specifically cleave messenger RNA molecules are currently being used both as experimental tools and as therapeutic agents. Mechanisms of action of various oligonucleotide-based drugs, recent developments in the drug-delivery approaches, and future potentials are discussed in this review. PMID- 9367794 TI - A common 844INS68 insertion variant in the cystathionine beta-synthase gene. AB - Mildly elevated plasma homocysteine has been shown to be associated with an elevated risk for cardiovascular disease. In this study, we analyzed the frequency of a common 844ins68 insertion variant in the cystathionine beta synthase gene (CBS) in patients with arterial occlusive disease and in controls and assessed the association between the insertion variant and plasma homocysteine concentrations. The insertion variant was equally distributed between both study groups. Furthermore, the presence of this insertion variant, either in the heterozygous or the homozygous state, is not associated with hyperhomocysteinemia. We therefore conclude that this common 844ins68 variant is a neutral insertion variant. PMID- 9367795 TI - Phenotypic comparison of an osteogenesis imperfecta type IV proband with a de novo alpha2(I) Gly922 --> Ser substitution in type I collagen and an unrelated patient with an identical mutation. AB - We examined the type I collagen synthesized by cultured dermal fibroblasts from a patient affected with osteogenesis imperfecta (OI) type IV. Both normal and abnormal trimers were produced. The mutant collagen molecules were excessively modified intracellularly, had a melting temperature 4 degrees C lower than the control, were secreted at a reduced rate, and underwent delayed processing to mature alpha chains.Molecular investigations identified a G --> A transition in one COL1A2 allele, resulting in a Gly922 --> Ser substitution in the alpha2(I) chain. The proband's mutation was demonstrated to arise "de novo" by the absence of the mutant allele restriction enzyme pattern from parental genomic DNA.We analyzed the insoluble extracellular matrix deposited by long-term cultured fibroblasts from our patient and from a previously described unrelated individual who carries an identical substitution. In both cases, the mutant chain constituted 10-15% of the total alpha chains deposited.We also present here the first detailed comparison of phenotype between unrelated OI patients with an identical collagen mutation. These two patients are both Caucasian females, ages 8 and 9 years, each diagnosed as type IV OI by the Sillence classification. They have a similar phenotype including moderate skeletal fragility with several femur fractures, dentinogenesis imperfecta, wormian bone, and reduced height and weight. We conclude that this phenotype is related both to the location of this mutation and to the similar extent of matrix incorporation by the mutant chains. Molecular and biochemical studies of unrelated individuals with identical amino acid substitutions in type I collagen resulting in either similar or dissimilar clinical outcomes will make a significant contribution to identifying the factors involved in the modulation of the OI phenotype. PMID- 9367796 TI - Enhanced resistance of adriamycin-treated MCR-5 lung fibroblasts by increased intracellular glutathione peroxidase and extracellular antioxidants. AB - Considerable evidence indicates that reactive oxygen species play an etiological role in both cardiotoxicity and the skin necrosis induced by adriamycin (ADM). An increase in glutathione peroxidase activity on addition of selenium to cultured MCR-5 lung fibroblasts was observed; this increase was accompanied by enhanced cellular resistance to ADM toxicity. Moreover, the presence of exogenous antioxidant systems, such as superoxide dismutase, catalase, vitamin E, dimethylsulfoxide, and desferroxamine, an iron chelating agent, resulted in significant protection from ADM-mediated damage. PMID- 9367797 TI - Cholesteryl ester storage disease: relationship between molecular defects and in situ activity of lysosomal acid lipase. AB - The molecular defects in the LIPA gene encoding the lysosomal acid lipase (LAL) were investigated in two unrelated patients affected with cholesteryl ester storage disease (CESD), an autosomal recessive disorder associated with LAL deficient activity. In cell lysates from both patients there was a severely reduced LAL activity. In a female patient, nucleotide sequencing of amplified LAL genomic DNA or reverse-transcribed mRNA demonstrated that she was a compound heterozygote for two previously reported mutations, a G --> A transition at position -1 of the exon 8 splice donor site, resulting in skipping of the complete exon 8, and a C923 --> T substitution leading to the replacement of His274 to Tyr. The second, male CESD patient was heterozygous for the splice junction mutation and a yet undescribed C --> T substitution at position 233, which introduces a premature in-frame termination codon. The functional consequences of these genetic alterations were evaluated for the first time by studying the catabolic turnover of radiolabeled cholesteryl oleate in intact cells. A lower in situ residual LAL activity was found in cells carrying the stop codon mutation than in cells having the His274 --> Tyr substitution. Since the severely reduced LAL activity was seen in cells from an adult patient with a mild CESD, we conclude that there is no simple direct correlation between the LAL molecular lesions and the biochemical and clinical phenotypes. PMID- 9367798 TI - Subnuclear localization of protein kinase C delta in beta cells. AB - Our laboratory has previously shown that beta cells express multiple isoforms of protein kinase C (PKC) and that some isoforms are located to multiple pools within the cell, including the cytoskeletal elements. In this study we analyzed the localization of the delta, epsilon, zeta, beta, and alpha isoforms of PKC to the nucleus. Nuclei were isolated from insulinoma beta cells and fractionated by centrifugation to give the nuclear soluble fraction, nuclear membrane fraction, and the insoluble matrix. The nuclear pellet was enriched in DNA and contained less than 5% of the total cellular nucleotidase activity. The nuclear membrane contained less than 2% of the total cellular nucleotidase activity, suggesting negligible plasma membrane contamination. Analysis of cellular fractions by immunoblotting with isoform-specific anti-PKC antibodies showed that PKC alpha, beta, zeta, and epsilon could be detected in the soluble fraction of the cell but could not be detected in the nucleus. Only PKC delta could be detected in the nucleus and was mostly present in the nuclear membrane fraction. There was light staining in the nucleocytosol and the nuclear matrix but the enzyme in the nuclear membrane represented approximately 76% of the total nuclear enzyme. Nuclear PKC delta constituted approximately 9% of the total cellular enzyme. Phorbol ester (1 microM, 15 min) increased the levels associated with the nuclear membrane approximately threefold but not to the nuclear matrix or nucleocytosol. Inhibition of PKC with MDL 29152 increased levels of preproinsulin mRNA relative to beta-actin mRNA levels, while chronic phorbol ester treatment led to a slight decrease. Taken together, these data suggest that PKC is constitutively active in the nucleus and may be important in modulating preproinsulin mRNA levels. PMID- 9367799 TI - The pathogenetic role of heme in pregnancy-induced hypertension-like disease in ewes. AB - Toxicosis syndrome of fasting pregnant ewes has a close similarity to human preeclampsia (hypertension, albuminuria). The common etiological factor might be oxidative hemolysis and heme-induced endothelial damage. Ewes (5 starving, 5 control) at 130-135 gestational days with a 96-h fasting period followed by refeeding were used. Blood pressure, platelet count, electrolytes, kidney and liver function parameters, as well as plasma glucose, hemoglobin/heme, free thiol groups and Trolox equivalent antioxidant capacity, and plasma iron and ferritin levels were measured. Statistical significance was assessed using Student's t test (P < 0.05). Besides hypertension and renal disturbances, hemolysis, elevated liver enzymes and low platelet count, characteristic of human HELLP syndrome, were also present. In the first 24 h of glucose deprivation there was a significant rise in both the plasma hemoglobin/heme and indirect bilirubin concentrations. The antioxidant free thiol levels decreased significantly the next day, without any change in the total antioxidant capacity of the plasma. While the loss of calcium and magnesium levels related to the similarity to preeclampsia, reduced plasma iron concentrations referred to species differences in iron homeostasis. An oxidative stress causing hemolysis in a glucose-6 phosphate dehydrogenase-deficient animal model was proven by the loss of free thiols after glucose deprivation. The activation of the oxidative stress protein heme oxygenase was a signal of endothelial cell injury, the primary cause of pregnancy-induced hypertension. PMID- 9367800 TI - Increased glucagon action on lactate gluconeogenesis in perfused liver of dexamethasone-treated rats. AB - To clearly understand the hyperglycemic action of glucocorticoids, we studied the action of glucagon on lactate gluconeogenesis in the liver of rats 7 days after adrenalectomy and after treatment with 1 mg/kg dexamethasone for 7 days. The liver was isolated and cyclically perfused at 20 ml/min with 25 ml of perfusion medium containing 5 mM lactate, [U-14C]lactate, and 0-100 ng/ml glucagon. In the absence of glucagon, incorporation of [14C]lactate into glucose carbon 1 did not change significantly in the adrenalectomized rat liver (1.66 +/- 0.12% of total radioactivity for 5 min) and increased in the dexamethasone-treated rat liver (3. 61 +/- 0.54%, P < 0.01) compared to the normal rat liver (1.99 +/- 0. 28%). The response of lactate gluconeogenesis to glucagon was extremely blunted in the adrenalectomized rat liver and was much larger in the dexamethasone-treated rat than in the normal rat liver (at a glucagon concentration of 100 ng/ml, 2.13 +/- 0.33, 8.55 +/- 1. 06, and 4.61 +/- 0.53% for 5 min, respectively). Glucagon binding to liver plasma membrane was not changed by adrenalectomy and was decreased by dexamethasone treatment. These results suggest that glucocorticoids induce hyperglycemia by increasing the response to glucagon, together with the high basal activity of hepatic gluconeogenesis. In addition, these effects do not occur through changes in glucagon binding to receptors. PMID- 9367801 TI - Changes in plasma glucose, insulin, glucagon, catecholamine, and glycogen contents in tissues during development of alloxan diabetes mellitus in rats. AB - Alloxan monohydrate (ALX) was given to rats (20 mg/100 g body weight) and plasma glucose (PG), immunoreactive insulin (IRI), immunoreactive glucagon (IRG), and catecholamine (CA) as well as the glycogen (G) content in the liver, muscle, and kidneys were measured. Although whether hypoglycemia was present immediately after injection was not clear, the PG level increased, with a modest peak after 2 h. The PG levels in rats receiving food 6 h after ALX injection increased substantially after 1 h and continued to increase after 24 h. Although the IRI level increased slightly 10 min after the injection, low amounts were present for up to 24 h due to continued fasting. There was a rise in the IRG level at 10 min after injection, and then it decreased again slowly to a low level during fasting. No change was observed in the CA level. Hepatic G further decreased at 30 min after ALX injection and started to increase from 2 h to a peak level after 18 h. Almost no changes were noted in muscle tissues. The G content in the renal cortex remained almost unchanged, although it tended to decrease slightly after 8 h. When rats were fed 6 h after ALX injection, the IRI level rose slightly. Hepatic G at 6 h after feeding was nearly equal to that during feeding itself, but it then decreased rapidly. Muscular G became equal to that during feeding. Renal G showed a clear tendency to increase 6 h after feeding and became about four times that during periods when rats were fed ad lib. In conclusion, not only PG, IRI, and IRG, but also tissue G levels were shown to change markedly in the early stage of ALX induced diabetes. PMID- 9367802 TI - Insulinotropic action of 1,2,3-Tri(methylsuccinyl)glycerol ester. AB - A novel ester of succinic acid, 1,2,3-tri(methylsuccinyl)glycerol ester (3SMG), was found to stimulate insulin release from rat pancreatic islets. In the presence of 7 mM d-glucose, a 10 microM concentration of 3SMG was sufficient to cause a significant increase in insulin output. The ester mimicked the effect of other nutrient secretagogues in enhancing the synthesis of islet peptides, with a preferential action on proinsulin as distinct from nonhormonal peptides, in decreasing 86Rb outflow from prelabeled islets, and in stimulating Ca2+ inflow into the islet cells. It is proposed, therefore, that 3SMG displays the attributes suitable for stimulation or potentiation of insulin release in noninsulin-dependent diabetes, without requiring administration in large amounts and, hence, without the risk of excessive hepatic gluconeogenesis. PMID- 9367803 TI - Sulfation of chondroitin/dermatan sulfate by cystic fibrosis pancreatic duct cells is not different from control cells. AB - Cystic fibrosis is associated with mutations of the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-regulated plasma membrane chloride channel. Cystic fibrosis patients have been reported to possess elevated sulfation of glycoconjugates, which may contribute to the pathogenesis of the disease. Sulfation of glycosaminoglycans by a cystic fibrosis pancreatic adenocarcinoma cell line homozygous for DeltaF508 (CFPAC-1), a control pancreatic cell line (PANC-1), two CFPAC-1 cell lines transfected with the gene for CFTR (PLJ-CFTR 4.7, TR20), and a mock-transfected CFPAC-1 control (PLJ-6) was investigated. Cells were radiolabeled with [35S]sulfate and [3H]glucosamine, and glycosaminoglycans secreted into the medium after 24 and 72 h were isolated. Chondroitinase ABC digestion of chondroitin/dermatan sulfate allowed the recovery of disaccharides which were analyzed for their degree of sulfation by strong anion-exchange HPLC. No differences in the extent of sulfation by any of the cell lines were noted. However, glycoaminoglycans synthesized by cystic fibrosis cells consistently exhibited twofold higher [35S]-sulfate:[3H]glucosamine ratios than the controls. We conclude that CFTR plays no role in the sulfation of chondroitin/dermatan sulfate by pancreatic cells and that isotope incorporation ratios alone are insufficient evidence of changes in sulfation levels. PMID- 9367804 TI - Demonstration of the presence of cyclic inositol phosphohydrolase in human urine. AB - Cyclic inositol phosphohydrolase (cIPH), cleaves the cyclic bond of cyclic inositol monophosphate (cIP) to yield inositol monophosphate. In this communication, we demonstrate the presence of cIPH in human urine. cIPH was measured in the 24-h urine samples of both male and female hospital patients. cIPH released per day ranged from 0 to 243 units in men (n = 16) and from 15 to 346 units in women (n = 18). Release of cIPH activity was not related to renal function as measured by creatinine clearance. HPLC ion-exchange chromatography or HPLC gel filtration of ammonium sulfate precipitate yielded a distinct cIPH peak with an apparent molecular weight of 40 kDa on gel filtration. This is the first demonstration of the presence of this enzyme in human urine. The large variation (over 20-fold) in the excretion of this protein suggests that it may have physiological and/or pathological significance. PMID- 9367805 TI - Tetrahydrobiopterin in the treatment of infantile hypertrophic pyloric stenosis. AB - Evidence is emerging that reduced nitric oxide production may be involved in the pathogenesis of hypertrophic pyloric stenosis. Nitric oxide synthase (NOS) requires tetrahydrobiopterin (BH4) for activity. Four infants with hypertrophic pyloric stenosis were treated with oral BH4 (10 mg/kg/day) for 2.5 days. Although plasma total biopterin increased significantly at 3, 27, and 51 h after BH4 administration, there was no effect on the production of plasma cGMP, nitrite, nitrate, or citrulline. Ultrasound investigations before and after the ingestion of BH4 revealed no changes in the hypertrophic pyloric stenosis. We conclude that oral BH4, in the dose utilized in our investigations, does not modify the cause of hypertrophic pyloric stenosis, presumably because it did not restore nitric oxide production in the nonadrenergic noncholinergic nerves of the enteric nervous system. PMID- 9367806 TI - Na-Li countertransport kinetics in the relatives of hypertensive patients with abnormal Na-Li countertransport activity. AB - Familial factors are believed to be important in determining the high sodium lithium countertransport activity (defined as >0.40 mmol Li/(h x l cell) at external sodium concentration of 140 mmol/L (Nae 140)) which is observed in a proportion of patients with essential hypertension. However, environmental factors such as pregnancy and dyslipidemia also affect activity. High sodium lithium countertransport activity (Nae 140) in essential hypertension is mainly due to a low Michaelis constant (Km) and is associated with a high Vmax/Km ratio. In contrast, dyslipidemias affect Vmax. This study aimed to determine if there was evidence that Km and Vmax/Km ratios are influenced by familial factors. Sodium-lithium countertransport kinetics were measured in the 47 first degree relatives of 12 hypertensive probands with abnormal sodium-lithium countertransport kinetics and 35 normotensive control subjects. Sodium-lithium countertransport was measured as Na-stimulated Li efflux from lithium loaded erythrocytes. The relatives had significantly reduced Km and increased Vmax/Km compared to normal subjects. Eleven relatives had high sodium-lithium countertransport activity (Nae 140), associated with low Km and high Vmax/Km. The 14 relatives that were hypertensive had abnormalities of sodium-lithium countertransport kinetics. The results of this study suggest that familial factors are important in determining the Km and Vmax/Km of sodium-lithium countertransport activity. Studies aimed at determining the inheritance of sodium lithium countertransport and its use as an intermediate phenotype of essential hypertension must measure its kinetic determinants to reduce the risk of confounding effects from other variables. PMID- 9367807 TI - Organ-specific over-sulfation of glycosaminoglycans and altered extracellular matrix in a mouse model of cystic fibrosis. AB - Cystic fibrosis (CF) is a fatal inherited disease caused by the loss of function of a plasma membrane chloride channel-the cystic fibrosis transmembrane conductance regulator (CFTR). It is characterized by viscous mucous secretions which have abnormal glycosylation and sulfation. The development of a CFTR knockout mouse has allowed in vivo experiments aimed at investigating the over sulfation phenomenon reported for CF glycoconjugates. Four CF and five control mice injected with [35S]sulfate were examined for differences in the sulfation of glycosaminoglycans (GAGs) synthesized by 12 tissues after 48 h. The liver and pancreas of CF mice incorporated significantly higher amounts of [35S]sulfate into GAGs (dpm/microg) than the controls, while the ileum, jejunum, colon, cecum, spleen, trachea, and gall bladder of CF mice exhibited higher incorporation levels that were not significant. The lung and nasal septum were not different, and the nasal mucosa of CF mice was significantly lower (P < 0.05). Structural analysis of the chondroitin/dermatan sulfate component by strong anion-exchange HPLC revealed that the liver and ileum of CF mice incorporated significantly more total sulfate than controls. However, for other organs, the explanation for higher isotope incorporation was a 40-50% higher specific activity of [35S]sulfate within GAGs. This finding implied different uptake kinetics of sulfate from the circulation or that CF mice have altered sulfate pools. CF mice also had altered proportions of chondroitin/dermatan sulfate to heparan sulfate in the ileum and gall bladder (P < 0.05). We conclude that extracellular matrix architecture in some CF organs may be abnormal and that sulfation of glycoconjugates by some organs and sulfate utilization in others have been affected by the loss of CFTR. This study provides the first in vivo evidence for an influence of CFTR on glycoconjugate sulfation and suggests other secondary manifestations of CFTR dysfunction associated with abnormalities of the extracellular matrix. PMID- 9367808 TI - Retrovirus vectors displaying the IgG-binding domain of protein A. AB - We have designed and constructed retrovirus particles displaying the IgG-binding domain of protein A. We fused the gene for the synthetic antibody-binding portion of protein A with the envelope gene of ecotropic Moloney murine leukemia virus. The fusion gene was coexpressed in ecotropic retroviral packaging cells, and retrovirus particles with IgG-binding activities were recovered. In principle, the protein A-envelope chimeric retrovirus complexed with specific monoclonal antibody could be used for cell-targeted gene delivery. PMID- 9367809 TI - Oxidation of bilirubin by rat brain mitochondrial membranes-genetic variability. AB - Bilirubin is oxidized by brain mitochondrial membranes at a rate which may contribute significantly to clearance of bilirubin from brain. Different strains of congenitally jaundiced rats (Gunn rats) vary widely as far as the mortality rate of the homozygous (jaundiced) pups. Because the ability to oxidize bilirubin in brain may protect against toxicity, we hypothesized that the ability to oxidize bilirubin would be lower in Gunn rat strains (ACI/N-j) with a high mortality rate in the homozygous pups. Mitochondria were obtained from young rat brains by differential centrifugation in sucrose gradients. The mitochondria were ruptured by sonication. The change in optical density of a bilirubin solution at 440 nm was measured over time following addition of the membrane suspension. The rate of bilirubin oxidation was significantly lower in rats of the RHA/N-j strain both at 7-8 days of age and in adults, compared to rats of the ACI/N-j and the Sprague-Dawley strains at the same age points. Differences in mortality rates between the RHA/N-j and the ACI/N-j strains of Gunn rats could not be explained on the basis of differences in the ability of brain mitochondrial membranes to oxidize bilirubin, as these activities were lower in the RHA/N-j rats, which also have lower mortality rates, but higher in the ACI/N-j rats, which have remarkably high mortality rates. This study also confirmed previous findings relative to age maturation of the enzyme activity. PMID- 9367810 TI - Sequence analysis of the 3' hypoxia-responsive element of the human erythropoietin gene in patients with erythrocytosis. AB - Erythrocytosis arises from a variety of pathogenic mechanisms. We sequenced a 256 bp region 3' to the erythropoietin (Epo) gene which included a 24- to 50-bp minimal hypoxia-responsive element spanning HIF-1- and HNF-4-binding sites in 12 patients with erythrocytosis and 4 normal subjects. Four polymorphisms were found, none of which affected the HIF-1-binding site, although one polymorphism was present in the HNF-4 consensus region. The data indicate that none of these polymorphisms cause erythrocytosis. PMID- 9367811 TI - Three phase partitioning: concentration and purification of proteins. AB - Three phase partitioning (TPP) uses t-butanol and ammonium sulfate to precipitate enzymes and proteins from aqueous solutions. The method is useful both upstream with crude samples and downstream where a scaleable simple step is needed. About 25 enzymes and proteins have been isolated by various laboratories using TPP-t butanol. The relation of t-butanol used in TPP, with n-butanol used as an extraction agent from Morton's work, is reviewed. Some t-butanol appears bound to TPP-precipitated proteins which are actually protein-t-butanol coprecipitates. They float above denser aqueous salts because bound t-butanol increases their buoyancy, similar to the behavior of many lipoproteins. On redissolving TPP precipitated enzymes, total and specific activities usually are regained and sometimes increased. Sulfate ion-in large concentrations-likely exerts itself through its kosmotropic action as in conventional salting out. t-Butanol likewise appears to be a kosmotrope and crowding agent at room temperature or above, whereas C1 and C2 cosolvents (e.g., ethanol) do not so behave except at near or below zero temperatures. However, kosmotropy is not the entire origin of TPP, nor probably of conventional salting out. Electrostatic forces, capacity to force protein conformation tightening and protein hydration shifts, also contribute. Electrostatic forces, and the tendency for salt ions to bind and tighten protein molecule conformation, are indicated by the sharp pH dependency of both conventional salting out and TPP, around pH regions where proteins undergo conformation changes. Sulfate anion is densely-perhaps extraordinarily-hydrated, adding much to its effective size, and therefore it has a tendency to crowd or exclude proteins, when sulfate concentrations are in the 0.5 to 3 M range. PMID- 9367812 TI - Purification of ribonucleases Sa, Sa2, and Sa3 after expression in Escherichia coli. AB - The genes for three small ribonucleases from different strains of Streptomyces aureofaciens have been cloned and expressed in Escherichia coli. The purification of these ribonucleases from the periplasmic space is described. The yields range from 10 to 50 mg of protein per liter of culture medium. The molar absorption coefficients, isoelectric pH values, and pH of optimum activity are reported. PMID- 9367813 TI - Refolding of a recombinant collagen-targeted TGF-beta2 fusion protein expressed in Escherichia coli. AB - In this study, a tripartite transforming growth factor-beta (TGF-beta2) fusion protein bearing an N-terminal purification tag and an auxiliary collagen binding decapeptide has been constructed and expressed at high levels in Escherichia coli. The resulting recombinant protein accumulates in an insoluble and biologically inactive inclusion-body complex. The insoluble protein was solubilized in guanidine hydrochloride and a Ni-chelating affinity column was utilized to isolate the 13.5-kDa TGF-beta2 fusion protein, which was then refolded into its native conformation under controlled redox conditions. The formation of native homodimers was monitored by nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis gradient gels and the bioactivity determined by a quantitative TGF-beta assay system using mink lung epithelial cells transfected with a plasminogen activator inhibitor-1 promoter/luciferase reporter plasmid. To optimize yields, renaturation conditions including denaturants, limiting protein concentrations, redox ratios, dialysis conditions, and refolding kinetics were studied and monitored by bioactivity. These studies demonstrate that recombinant TGF-beta2 fusion proteins can be produced in E. coli and renatured into biologically active homodimers. Furthermore, they confirm that the auxiliary collagen binding domain effectively targets the recombinant growth factor to type I collagen. Taken together, these studies advance the technology necessary to generate large quantities of targeted TGF-beta fusion proteins for specific biomedical applications. PMID- 9367814 TI - Expression in Escherichia coli of the thermostable DNA polymerase from Pyrococcus furiosus. AB - Pfu, the DNA polymerase from Pyrococcus furiosus, has the lowest error rate of any known polymerase in polymerase chain reaction (PCR) amplification. Previously the protein has been purified from P. furiosus bacterial cultures, and a recombinant form has been produced in a baculovirus system. We have produced a pET plasmid for expression of Pfu in Escherichia coli (the expression plasmid pETpfu is available from ATCC, Accession No. 87496) and found that this plasmid is toxic or unstable in the expressing strain BL21(DE3), even in the absence of induction. However, the plasmid was stable in BL21(DE3) containing the pLysS plasmid, which suppresses expression prior to induction, and a 90-kDa protein was expressed upon addition of isopropyl beta-D-thiogalactopyranoside. The protein was purified by heating (to denature E. coli proteins), followed by chromatography on P11 phosphocellulose and mono Q columns. The purified protein had the same activity as the commercially obtained baculovirus-expressed Pfu in both DNA polymerase and PCR reactions. This bacterial expression system appears to be the method of choice for production of Pfu. PMID- 9367815 TI - Expression, purification, and characterization of rat aromatic L-amino acid decarboxylase in Escherichia coli. AB - A cDNA encoding rat aromatic L-amino acid decarboxylase (AADC) was successfully expressed in Escherichia coli using a T7 RNA polymerase expression system. Two types of expression vectors were tested and revealed to be equivalent to produce AADC. The enzyme was purified in both cases. The ratio of recovery of the pure active recombinant protein was better when the purification of the protein was made easier by addition of a short His-Tag at the C-terminal moiety of AADC, as achieved in the case of pET-20b+ vector expression. Spectral characteristics of the bound pyridoxal-5'-phosphate were essentially identical to the spectral properties of rat AADC. Kinetic constants Km and Vmax of recombinant AADC for the natural substrates L-dihydroxyphenylalanine and 5-hydroxytryptamine were 0.14 mM and 8444 U/mg, and 0.066 mM and 1813 U/mg, respectively. These values were in good agreement with previously reported values for AADC of the rat and other mammalian species. PMID- 9367816 TI - Recombinant expression and purification of the botulinum neurotoxin type A translocation domain. AB - Botulinum neurotoxin type A in its fully activated form exists as a dichain protein consisting of a 50-kDa light chain and a 100-kDa heavy chain linked by a disulfide bond (B. R. DasGupta and H. Sugiyama, Biochem. Biophys. Res. Commun. 48, 108-112, 1972). The protein can be further subdivided into three functional domains: a catalytic domain corresponding to the light chain, a translocation domain associated with the N-terminal half of the heavy chain, and a binding domain as the C-terminal half. To facilitate further structural and functional studies on the mechanism of toxin translocation, we report here the recombinant Escherichia coli expression and purification of the isolated translocation domain with a yield of 1 mg pure protein per 1 g cell paste. Circular dichroism, enzyme linked immunosorbent assays, and preliminary crystallization experiments verify proper protein folding. This reagent should serve as a key tool in elucidating the mechanism of translocation and in determining how the catalytic domain, a large 50-kDa metalloprotease, is delivered to the cytosol. PMID- 9367817 TI - High-level expression of ovine growth hormone in Escherichia coli: single-step purification and characterization. AB - The gene for ovine growth hormone (oGH) was expressed without signal sequences in Escherichia coli. A recombinant plasmid expression vector has been constructed which directs the synthesis of a fusion protein containing a stretch of six histidine residues (His6) at the amino-terminus under the control of a T5 promoter. Upon induction with isopropyl-beta-D-thiogalactopyranoside, the recombinant protein was synthesized and accumulated in the cytoplasm in the form of inclusion bodies, at levels of approximately 18% of the total cellular protein. The recombinant ovine growth hormone containing His tag was recovered and purified to >95% homogeneity in a single step by immobilized metal-ion chromatography with a special affinity Ni2+.NTA resin that has selectivity for proteins with neighboring histidine residues. Characterization by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by immunoblotting and amino terminal analysis demonstrated the authenticity of the fusion protein. The purified RoGH after refolding was found to be functionally active in terms of its receptor binding and antigenicity as analyzed by radio receptor assay and radio immuno assay. Yields of the purified expressed protein were found to be 32 microg/ml at a shake-flask level. Thus, results indicate that a combination of E. coli expression and affinity purification by Ni2+.NTA chromatography promises to be a rapid method to produce oGH for use in structure-function studies. PMID- 9367818 TI - Expression of the catalytic subunit (UL54) and the accessory protein (UL44) of human cytomegalovirus DNA polymerase in a coupled in vitro transcription/translation system. AB - The catalytic subunit (UL54) and accessory protein (UL44) of human cytomegalovirus (HCMV) DNA polymerase have been cloned and expressed in an in vitro-coupled transcription/translation reticulocyte lysate system. The influence of the 5'-untranslated region (5'-UTR) on the efficiency of expression from the circular plasmids has been investigated. For expression of both UL54 and UL44, a truncated form of the alfalfa mosaic virus (AMV) RNA4 5'-UTR was found to be superior to the full-length AMV 5'-UTR or the original HCMV 5'-UTRs of different lengths. Protein products with Mr approximately 140 and 55 kDa were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis in the UL54 and UL44 in vitro expression reactions, respectively. The properties of the expressed enzyme were compared with those of native HCMV DNA polymerase purified from HCMV-infected cells. DNA polymerase and 3'-5' exonuclease activities of the expressed UL54/UL44 complex were found to be dependent on salt concentration in the same manner as the activities of the native enzyme. The in vitro-expressed enzyme resembles the purified HCMV DNA polymerase in its affinity for deoxynucleoside triphosphates as well as in its sensitivity to known inhibitors (cidofovir diphosphate, ganciclovir triphosphate, and foscarnet). This straightforward method for protein expression may also be applicable to other enzymes where reproducible generation of fully functional products is desirable. PMID- 9367819 TI - Purification in quantity of the secreted form of WI-1: a major adhesin on Blastomyces dermatitidis yeasts. AB - WI-1, a 120-kDa adhesin on Blastomyces dermatitidis, binds the yeast to macrophages and is a major target antigen of immune recognition in acquired resistance to the fungus. In past studies, WI-1 has been purified by extracting the protein from the yeast cell wall, which yields microgram quantities for biological assays. We report a strategy for generating and purifying the secreted form of WI-1 in quantity. Yeasts of B. dermatitidis ATCC strain 60636 cultured in HMM medium were found to secrete 10 microg/ml of WI-1 into a supernate relatively free of other medium and yeast components. Using a two-step method of ion exchange and hydrophobic interaction chromatography, we achieved a 7.1-fold purification of WI-1. Purified WI-1 was sequenced at the N-terminus which revealed that the secreted protein exists in two different forms. In functional assays, purified WI-1 also retained its adhesivity for human macrophages, and its antigenicity in binding anti-WI-1 antibodies and stimulating T-cells to proliferate, but it lost some capacity to elicit delayed-type hypersensitivity in mice. These findings advance our understanding of the WI-1 adhesin/antigen and our ability to express and purify WI-1 in quantity and will permit a study of the relationship between three-dimensional structure and activity of the molecule. PMID- 9367820 TI - Hepatocyte growth factor (HGF) as a tissue organizer for organogenesis and regeneration. PMID- 9367821 TI - Effects of Mn2+ and oxalate on the catalatic activity of manganese peroxidase. AB - Manganese peroxidase from Phanerochaete chrysosporium is an extracellular heme containing enzyme known to catalyze the oxidation of Mn2+ to Mn3+ in a reaction requiring oxalate or another appropriate manganese chelator. We have found that the enzyme can also catalyze a manganese-dependent disproportionation of hydrogen peroxide when a manganese chelator is not included. The catalatic activity was observed in the pH range from 3.0 to 8.5, and the apparent second-order rate constant for catalatic reaction was about 2 x 10(5) M-1 s-1 at pH 4.5 to 7.0 at 25 degrees C. Oxalate inhibited oxygen production by increasing the apparent K(m) for Mn2+ for catalatic activity from micromolar to millimolar levels and facilitating peroxidase activity. Catalase-type function was recovered by excess of Mn2+ in the presence of oxalate. We propose that catalatic activity may protect the enzyme from inactivation by hydrogen peroxide in an environment where free oxalate may be limited. PMID- 9367822 TI - Palmitoylation of tubulin. AB - Tubulin is a very water soluble protein, yet a significant portion is firmly associated with cell membranes. Because recent work has shown that palmitoylation is a dynamic process that can alter the targeting of proteins to membranes, we tested whether or not tubulin could be palmitoylated to account for its membrane location. Tubulin acylation was measured by incorporation of [3H]palmitate into PC12 cells in culture. We found palmitoylated tubulin in both cell pellet and cytosol with a higher concentration in the former. EGF-stimulated PC12 cells incorporated the same amount of palmitate per unit protein but the proportion in the membrane fraction was enhanced. More palmitate of the pellet was found in alpha than beta tubulin; EGF stimulation primarily increased palmitate in beta tubulin. In addition we found that palmitic acid was present both as thioesters and as oxyesters. We suggest that palmitoylation may contribute to the membrane localization of tubulin and can be regulated by growth factors. PMID- 9367823 TI - Geldanamycin-induced destabilization of Raf-1 involves the proteasome. AB - The Raf-1-MEK-MAPK pathway plays an important role in transducing extracellular growth factor signaling into altered nuclear transcription factor function. The benzoquinone ansamycin Geldanamycin (GA) specifically binds to the heat shock protein HSP90 and alters its complex with Raf-1. This leads to a decrease in Raf 1 levels and to disruption of the Raf-1-MEK-MAPK signaling pathway. The enhanced degradation of Raf-1 protein was prevented by inhibitors of the proteasome, while inhibition of lysosomal or other proteases was ineffective. Raf-1 that was protected from GA-induced degradation was of higher molecular weight and showed a laddering pattern consistent with its polyubiquitination. Unlike Raf-1 in untreated cells, the protein was insoluble in Triton X100- or NP40-based buffers. Signaling through this pathway was inhibited by GA, concomitant with loss of Raf 1 protein, but was restored if Raf-1 was protected from GA-induced degradation by proteasome inhibitors. PMID- 9367824 TI - Suppression of cytochrome P450 Cyp2f2 mRNA levels in mice by the peroxisome proliferator diethylhexylphthalate. AB - Exposure to peroxisome proliferators, which are extensively used, causes a number of pleiotrophic effects. Prolonged exposure to the peroxisome proliferator, DEHP, causes hepatic hyperplasia and liver tumors in rats and mice. This exposure can also induce a number of enzymes. To identify additional genes that are regulated by DEHP, mRNA differential display was used. One of the genes affected is cytochrome 450 Cyp2f2, a naphthalene hydroxylase. Using northern analysis, RNase protection assay, and RT-PCR, we show that the Cyp2f2 mRNA levels are decreased in mouse liver following DEHP treatment. A smaller Cyp2f2 mRNA transcript was also detected in kidney and these transcript levels were also suppressed but to a lesser extent than that in the liver. The response to DEHP in mouse liver is both dose and time dependent. PMID- 9367825 TI - Effects of short and long term ethanol on the activation of signal transducer and activator transcription factor 3 in normal and regenerating liver. AB - Interleukin-6 (IL-6) induced activation of Signal Transducer and Activator Transcription Factor 3 (Stat3) is a critical step in liver regeneration. Chronic ethanol consumption is known to increase the plasma concentration of IL-6, yet the ability of the liver to regenerate and the regenerative induction of several IL-6 initiated events are impaired in chronic alcoholic liver disease. We hypothesized that chronic ethanol consumption inhibits IL-6 dependent signal transduction. To test this hypothesis, the effect of ethanol on the Stat3 signal transduction pathway was studied in the adult rat liver. In vitro treatment of freshly isolated normal adult rat hepatocytes with 50-100 mM ethanol for 30 min blocked IL-6-induced Stat3 activation. Long-term ethanol intake in vivo significantly attenuated the activation of Stat3 induced either in vivo by partial hepatectomy or in vitro by IL-6. In contrast, short-term ethanol consumption enhanced the regenerative induction of Stat3 but inhibited IL-6 induced Stat3 activation. These data suggest that the inhibition of liver regeneration by chronic ethanol consumption is, at least in part, mediated by modulating the activation of Stat3. PMID- 9367826 TI - Fc epsilon RI aggregation induces tyrosine phosphorylation of a novel 72 kDa protein downstream of Syk. AB - Tyrosine phosphorylation of proteins is critical for the Fc epsilon RI-induced signal transduction that leads to the release of inflammatory mediators from mast cells. Here we report the isolation of a monoclonal antibody, mAb BD2, to a 72 kDa protein that becomes rapidly tyrosine phosphorylated after Fc epsilon RI aggregation. By immunoprecipitation, immunoblotting and/or protease digestion this 72 kDa protein was different from the previously identified 68-76 kDa tyrosine phosphorylated proteins Btk, paxillin, SLP-76 or Syk. The phosphorylation of this 72 kDa protein was detectable within 15 sec after receptor aggregation and was independent of Ca2+ influx or the activation of protein kinase C. By in vitro kinase reaction, the 72 kDa protein did not autophosphorylate, which suggests that it is not a kinase, but is associated with a 140 kDa protein that was strongly phosphorylated. Studies in Syk deficient and Syk transfected variants of the RBL-2H3 cells demonstrated that the tyrosine phosphorylation of this 72 kDa protein was downstream of Syk. These data indicate that the 72 kDa protein precipitated by mAb BD2 is a novel phosphoprotein involved in Fc epsilon RI signaling. PMID- 9367827 TI - Dexamethasone and interleukin-1 potently synergize to stimulate the production of granulocyte colony-stimulating factor in differentiated THP-1 cells. AB - The human monocytic leukemic cell line, THP-1, which differentiates toward macrophages in response to phorbol 12-myristate 13-acetate (PMA) was investigated for its ability to produce granulocyte colony-stimulating factor (G-CSF). G-CSF protein was neither produced during PMA-induced differentiation nor in response to dexamethasone (Dex) alone. However, when combined, PMA and Dex synergistically stimulated THP-1 cells to produce G-CSF. The synergistic interaction between PMA and Dex on G-CSF production appeared to be mediated through the production of interleukin-1 (IL-1) since neutralization of IL-1 activity completely inhibited G CSF production. Further experiments demonstrated that in THP-1 cells pretreated with PMA, Dex potently synergized with IL-1 to stimulate G-CSF production. PMID- 9367828 TI - Activation of gene expression by a non-transforming unmyristylated-SH3-deleted mutant of Src is dependent upon Tyr-527. AB - v-Src transcriptionally induces gene expression by activating several transcriptional response elements such as the serum response element (SRE), the 12-O-tetradecanoylphorbol-13-acetate (TPA) response element (TRE), and the c-AMP response element (CRE) found in the promoters of several proliferation-related immediate early genes. We report here that a Src protein, with a deletion in the SH3 domain and lacking a membrane localization signal, strongly activates gene expression mediated by SRE, TRE and CRE transcriptional control elements. This mutant was unable to cause cellular transformation, suggesting that activation of these transcriptional control elements is not sufficient for the induction of a transformed phenotype by Src. Interestingly, the ability of the membrane localization and SH3 deletion mutant to activate gene expression was abolished upon conversion of the C-terminal inhibitory Tyr-527 to Phe. These data suggest the existence of previously unreported Tyr-527-dependent activation of intracellular signals that activate gene expression. These data raise the possibility that Src may exert physiological effects via an interaction between Tyr-527 and an SH2-containing protein that would interact with the phosphorylated form of Tyr-527. PMID- 9367829 TI - A valine421 to methionine mutation in IS6 of the hscp voltage-gated sodium channel associated with pyrethroid resistance in Heliothis virescens F. AB - Multiple mutations in a locus encoding a voltage-gated sodium channel have been predicted for pyrethroid resistance in insects. Previously we reported a mutation associated with pyrethroid resistance, Leu1029 to His, in domain II transmembrane segment S6 (IIS6) of the Heliothis virescens F. sodium channel (para homologue) hscp locus. Sequence analysis of additional resistance haplotypes 5' to this mutation in the hscp locus has uncovered a G to A transition leading to a Val to Met mutation at amino acid position 421 in IS6 (V421M, numbering from Drosophila para). The V421M mutation is found only in a unique resistant haplotype, but not in two susceptible and a distinct resistant haplotype carrying the L1029H mutation. Implications of this finding in the evolution and mechanisms of pyrethroid resistance are discussed. PMID- 9367830 TI - Cloning and functional expression of a swelling-induced chloride conductance regulatory protein, plCln, from rabbit ocular ciliary epithelium. AB - The cDNA encoding a swelling-induced chloride conductance regulatory protein, plcln, was cloned from rabbit ciliary epithelium by using a polymerase chain reaction (PCR)-based approach. The open reading frame encoding 236 amino acids possesses high amino acid identity (93/%) with the previously cloned plcln from human ciliary epithelium. Outwardly rectifying currents were recorded in Xenopus oocytes injected with plcln cRNA, a result consistent with plcln expression in ciliary epithelium. A widespread distribution and marked expression of plcln mRNA in both nonpigmented ciliary epithelial (NPE) cells and pigmented ciliary epithelial (PE) cells was found for the first time. In situ hybridization analysis showed that plcln expression is more abundant in NPE than PE. These findings are consistent with the idea that plcln may be an important regulatory element in these secretory cells. PMID- 9367831 TI - Identification of a second SH2-domain-containing protein closely related to the phosphatidylinositol polyphosphate 5-phosphatase SHIP. AB - Distinct inositol and phosphatidylinositol polyphosphates 5-phosphatases have recently been cloned. Primers have been designed coding for highly conserved amino acid regions that are shared between sequences of 5-phosphatases. One of the PCR fragment referred to as 51 C, shows 99% identity to a previously reported sequence (INPPL-1) present in the database. We report here the identification of cDNAs for a new SH2-domain-containing protein showing homology to the inositol 5 phosphatase SHIP and therefore referred to as SHIP2. SHIP2 differs at both N- and C-terminal ends with the sequence of INPPL-1. The translated sequence of SHIP2 encodes a 1258 amino acid protein with a predicted molecular mass of 142 kDa. Particularly high levels of SHIP2 were found in human heart, skeletal muscle and placenta as shown by Northern blot analysis. SHIP2 was also expressed in dog thyroid cells in primary culture where the expression was enhanced in TSH and EGF stimulated cells. PMID- 9367832 TI - Inhibition of endogenous cardiac phosphatase activity and measurement of sarcoplasmic reticulum calcium uptake: a possible role of phospholamban phosphorylation in the hypertrophied myocardium. AB - The activity of the sarcoplasmic reticulum (SR) CaATPase in cardiac muscle is regulated by phospholamban via its ability to be phosphorylated. It is unclear what role phospholamban phosphorylation plays in cardiac adaptation and disease. The study of the native phospholamban phosphorylation in tissue has been technically difficult because of the presence of endogenous enzymes. Using mobility shifts on SDS PAGE gels we have demonstrated that significant dephosphorylation of phospholamban occurs during tissue homogenisation in the absence of phosphatase inhibitors. Endogenous kinases do not appear to alter phospholamban phosphorylation. When 10 mM NaF (a phosphatase inhibitor) was used in the preparation of crude SR homogenates, CaATPase activity (measured by oxalate stimulated calcium uptake) was stimulated almost 2 fold, p < 0.01. Increased CaATPase activity in NaF was associated with increased phospholamban phosphorylation. Phosphatase inhibitors were used in tissue homogenisation to determine phospholamban phosphorylation in normal hearts and in cardiac hypertrophy induced by abdominal aortic constriction. In 50 mM NaF which completely inhibits endogenous phosphatases, phospholamban from hypertrophied hearts had a slower mobility compared with normal hearts. This suggests that phospholamban was more highly phosphorylated in cardiac hypertrophy. Increased phospholamban phosphorylation following cardiac hypertrophy may enable the myocardium to compensate functionally in the early stages of adaptation. PMID- 9367833 TI - Retinoic acid inhibits cell growth in HPV negative cervical carcinoma cells by induction of insulin-like growth factor binding protein-5 (IGFBP-5) secretion. AB - Retinoids have been demonstrated to inhibit epithelial cell growth and differentiation. We examined the anti-proliferative effects of retinoic acid (RA) in an HPV positive and negative cervical carcinoma cell line. Our findings indicate that HPV-negative C33A cervical carcinoma cells are more sensitive to the growth inhibitory activity of retinoic acid (RA) than are HPV-positive CaSki cervical carcinoma cells. However, conditioned medium from RA-treated C33A cells displayed strong growth inhibitory activity in both C33A and CaSki cells. Since RA has been shown to modulate the expression of insulin-like growth factor binding proteins (IGFBPs) in many cells, we examined RA regulated expression of IGFBPs in medium isolated from RA treated C33A cells. IGFBP-5 was detectable in medium from C33A cells exposed to RA, and addition of purified exogenous IGFBP-5 resulted in growth inhibition of C33A cells. These results indicate that RA exerts it's anti-neoplastic effect in HPV negative cervical carcinoma cells via the overproduction of IGFBP-5. PMID- 9367834 TI - Overproduction of Mpd2p suppresses the lethality of protein disulfide isomerase depletion in a CXXC sequence dependent manner. AB - The third multicopy suppressor gene of the PDI1 deletion from Saccharomyces cerevisiae, MPD2, was isolated and characterized. The MPD2 gene encodes a protein with a putative signal sequence, ER retention signal, and a disulfide isomerase active site like sequence. The amino acid sequence around the active site like sequence is similar to the thioredoxin-like domains of PDI and PDI related proteins, although the similarity is comparatively low. A delta-pdi1 strain over producing Mpd2p showed slow growth and was sensitive to 1 mM dithiothreitol. Mpd2p can be detected in wild type cells and is a glycoprotein. Although the MPD2 gene was not essential for growth, overexpression of the gene partially restored the maturation defect of carboxypeptidase Y caused by the PDI1 deletion. Mutagenesis analysis revealed that Mpd2p can compensate for the loss of PDI with its CXXC sequence. PMID- 9367835 TI - Lack of infectivity of HIV-1 integrase zinc finger-like domain mutant with morphologically normal maturation. AB - The integrase (IN) encoded by human immunodeficiency virus type-1 (HIV-1) is required for integration of the viral DNA into a host cell chromosome. The function of the highly conserved HHCC motif in the HIV-1 IN amino-terminal zinc finger-like domain is still unknown. In this study, we examined the effect of mutations in the HHCC motif on viral infectivity, adsorption to and entry into target cells, and morphology in the context of a full-length form of an HIV-1 molecular clone. A complete lack of infectivity and de novo synthesized viral DNA of the HHCC mutants were demonstrated in both cell-free and co-culture infection systems using MT-2 or HeLa-CD4-LTR-beta-gal as target cells. The levels of viral adsorption to and entry into the target cells were determined by measuring the cell-associated p24 level in target MT-2 cells shortly after infection. We detected comparable cell-associated p24 levels of MT-2 cells after infection with wild-type and the mutant viruses. Taken together, these results suggest that the replication of HIV-1 carrying point mutations in the HHCC motif was blocked at the step after adsorption/ entry and prior to the initiation of reverse transcription, presumably at the uncoating step. Furthermore, electron microscopy revealed that the observed complete lack of viral infectivity caused by introducing an amino acid substitution into the HHCC motif is not always accompanied by apparent abnormal morphology or maturation of virus particles. PMID- 9367836 TI - Nitric oxide gates fertilization channels in ascidian oocytes through nicotinamide nucleotide metabolism. AB - In this paper we use the nitric oxide (NO) donor sodium nitroprusside to examine the response of the unfertilised oocyte of the ascidian Ciona intestinalis to nitric oxide. We show that the release of NO triggers an inward current that displays similar properties to the ascidian fertilisation current. Furthermore, the production of NO causes the release of intracellular calcium through a ruthenium-red sensitive mechanism. Our data suggest that these effects are due to the stimulation of nicotinamide nucleotide metabolism, but the active second messenger is not cyclic adenosine diphosphate ribose (cADPr). Finally, we show that NO production increases at fertilisation. The results suggest that ascidian sperm trigger the release of NO and this second messenger causes the breakdown of nicotinamide nucleotides leading to the production of a second messenger which induces the fertilisation current and may assist in the production of the increase in calcium. PMID- 9367837 TI - Phosphatidylinositol 3-kinase is required for the induction of ornithine decarboxylase in leukemia cells stimulated to growth. AB - The involvement of phosphatidylinositol 3-kinase (PI3K) in the induction of ornithine decarboxylase (ODC) was investigated by using specific PI3K inhibitors. In difluoromethylornithine-resistant L1210 cells stimulated to growth from quiescence, treatment with LY294002 inhibited cell growth and provoked a complete block of the induction of ODC activity (IC50 approximately 2 microM) and ODC protein. Some reduction in the accumulation of ODC mRNA was also observed, whereas ODC turnover was not affected significantly. Wortmannin, another specific inhibitor of PI3K, structurally unrelated to LY294002, also inhibited ODC induction with an IC50 of about 10 nM. These results indicate that PI3K activity is required for the induction of ODC, possibly affecting both ODC mRNA level and translation. Since p70 S6 kinase (p70S6K) is considered an important mediator of PI3K action in several experimental systems, the effect of rapamycin, which can lead to selective inhibition of p70S6K, was also investigated. Rapamycin inhibited p70S6K activity and produced ODC inhibiting effects similar to those elicited by LY294002. However, LY294002 and wortmannin at concentrations which inhibited almost completely PI3K activity did not decrease p70S6K activity, suggesting that p70S6K does not mediate the PI3K effects on ODC, but may lie on a separate pathway in this experimental model. PMID- 9367838 TI - 1 alpha,25-Dihydroxyvitamin D3 increases transforming growth factor and transforming growth factor receptor type I and II synthesis in human bone cells. AB - To determine whether the inhibition of human osteoblast growth mediated by 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25(OH)D3) occurs as a result of changes in transforming growth factor (TGF) and TGF receptor synthesis, we examined the effects of 1 alpha,25(OH)2D3 on the synthesis of TGF beta and TGF-beta receptors. Treatment with 1 alpha,25(OH)2D3, but not vehicle, increased TGF-beta 2 concentrations in human osteoblast cell supernantants in a dose- and time dependent manner. The increase in TGF-beta 2 concentrations was associated with an inhibition of osteoblast cell growth; antibodies directed against transforming growth factor beta partially blocked the inhibition of cellular growth mediated by 1 alpha,25-(OH)2D3 TGF-beta 2 gene transcription and TGF-beta 2 mRNA concentrations were increased in 1 alpha,25(OH)D3 but not in vehicle-treated cells. 1 alpha,25(OH)2D3 increased TGF-beta type I and type II receptor mRNA levels in osteoblasts. Increased expression of TGF-beta 2 and TGF-beta receptors by 1 alpha,25(OH)2D3 might account for the inhibition of human osteoblast growth seen following 1 alpha,25(OH)2D3 treatment. PMID- 9367839 TI - The HMC-1 human mast cell line expresses the hepatocyte growth factor receptor c met. AB - Hepatocyte growth factor (HGF) was originally characterized as a strong inducer of liver regeneration. However, it is now clear that HGF and its receptor, the proto-oncogene c-met, can be expressed in many other tissues, and that HGF can mediate diverse biological activities. We investigated the expression and function of c-met in a human mast cell line (HMC-1). We found that HMC-1 cells express c-met and that c-met expression can be upregulated by treatment of the cells with phorbol 12-myristate 13-acetate (PMA). Although HGF did not detectably influence the proliferation or morphology of HMC-1 cells, HGF inhibited the cells' ability to release tumor necrosis factor-alpha (TNF-alpha) in response to stimulation with PMA and the calcium ionophore, A23187. These results add the inhibition of TNF-alpha production to the other recognized effects of HGF/c-met on cellular function. PMID- 9367840 TI - The characteristic gene expressions of MAPK phosphatases 1 and 2 in hepatocarcinogenesis, rat ascites hepatoma cells, and regenerating rat liver. AB - mRNA levels of mitogen-activated protein kinase phosphatases, MKP-1 and MKP-2, were determined during chemical hepatocarcinogenesis and during regeneration of rat liver. In chemical hepatocarcinogenesis, the mRNA levels of MKP-1 were increased in primary hepatomas but decreased in rat ascites hepatomas as compared with normal liver. MKP-2 was undetectable in normal liver but strongly expressed in hepatomas. The MKP-2 mRNA level was increased with expression of malignant phenotypes in hepatomas. In regenerating liver, the mRNA level of MKP-1 increased immediately but transiently after partial hepatectomy, and peaked again on day 10, the time when hepatocytes cease proliferation. The elevated expression of MKP 1 on day 10 suggests some roles of MKP-1 as a negative regulator in hepatocyte proliferation. PMID- 9367841 TI - Identification of gene VI of filamentous phage phi Lf coding for a 10-kDa minor coat protein. AB - ORF95 in the filamentous phage phi Lf genome, locating behind gIII, was identified to be the gene (gVI) coding for minor coat protein pVI (95 amino acids, 10,245 dal). It was shown to be virion associated by Western blot analysis of chloroform-treated phage particles. Computer analysis predicted two transmembrane regions for this protein. Since no signal peptide was suggested and the size estimated by SDS-polyacrylamide gel electrophoresis matches that deduced from nucleotide sequence, it appears to be incorporated into the phage particle as its primary translational product. After completion of this study, eight genes organizing into an order of gVII-gX-gV-gVII-gIX-gIII-gIII-gVI have been identified for phi Lf. PMID- 9367842 TI - Genomic structures of cardiotoxin 4 and cobrotoxin from Naja naja atra (Taiwan cobra). AB - Two genomic DNAs with the size of 2.3 kb and 2.4 kb, which were isolated from the liver of Naja naja atra (Taiwan cobra), encoded the precursors of cardiotoxin 4 and cobrotoxin, respectively. Both genes shared virtually identical overall organization with three exons separated by two introns, which were inserted in the similar positions of the gene's coding regions. Moreover, their nucleotide sequences shared approximately 84.2% identity. This result reveals the evolutionary relationship between cardiotoxin and cobrotoxin. The exon/intron structures of cardiotoxin 4 and cobrotoxin genes were similar to that reported for erabutoxin c gene, a neurotoxin genomic DNA from a sea snake (Laticauda semifasciata). However, in contrast to the finding that the intron 2 of these genes had a similar size, a notable variation with the size of intron 1 was observed (1233 bp, 1269 bp and 197 bp for cardiotoxin 4, cobrotoxin and erabutoxin c genes, respectively). The different size with intron 1 is due to the middle region at the first intron of cardiotoxin 4 and cobrotoxin genes, which encoded small nucleolar RNA (snoRNA), being absent in that of erabutoxin c gene. These results, together with the finding of the potential mobility of snoRNA genes during evolution, suggest that intron insertions or deletions of snoRNA genes occur with the evolutionary divergence of snake neurotoxins and cardiotoxins. PMID- 9367843 TI - Isolation and characterization of Melanoplus sanguinipes adipokinetic hormone: a new member of the AKH/RPCH family. AB - A neuropeptide hormone isolated from corpora cardiaca of Melanoplus sanguinipes was purified by HPLC. The HPLC fractions were examined for adipokinetic activity with an in vivo bioassay. A single large UV absorbent peak was active in the mobilization of lipid while the other HPLC fractions showed no detectable activity. This large peak had a retention time and amino acid composition identical to synthetic Lom-AKH-I which was analyzed in a parallel manner. The primary sequence structure, pGlu-Leu-Asn-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2, was determined by automated gas-phase Edman degradation. The peptide was deblocked prior to sequencing using pyroglutamate aminopeptidase and the sequence was confirmed with mass spectrometry. The C-terminus of the peptide was determined to be blocked, as indicated by the lack of digestion with carboxypeptidase A. The knowledge of the primary sequence of Mes-AKH allows the use of a commercially available synthetic peptide and its antibodies for use in future research with Melanoplus sanguinipes. PMID- 9367844 TI - A molecular aspect of symbiotic interactions between the weevil Sitophilus oryzae and its endosymbiotic bacteria: over-expression of a chaperonin. AB - Specific proteins of symbiosis were analyzed by the comparison of two-dimensional electrophoresis protein patterns of symbiotic and aposymbiotic strains of the weevil Sitophilus oryzae. One protein was shown to be exclusively expressed in the aposymbiotic strain and three proteins, including a chaperonin, were characterized in the symbiotic strain pattern. The groE-like operon, encoding the two chaperonins groES and GroEL-like proteins of the endocytobiotes, was sequenced. It was found to be very similar to the groE operon of Escherichia coli (82% identity). In vitro and ex vivo experiments of protein labelling demonstrated that almost 40% of the endocytobiote protein synthesis ex vivo is focused on the GroEL-like protein. Finally, we showed by northern blotting that heat shock at 38 degrees C results in groEL mRNA accumulation inside the endocytobiotes. This work supports the hypothesis that chaperonins could have an essential physiological function in the maintenance of the symbiotic association. PMID- 9367845 TI - Production of 13-hydroxyoctadecadienoic acid (13-HODE) by prostate tumors and cell lines. AB - The major lipoxygenation product derived from linoleic acid, 13-(S) hydroxyoctadecadienoic acid (13-HODE), has been shown to be involved in cell proliferation and differentiation in a number of systems. Rapid detection of picogram amounts of this bioactive lipid in biological samples, however, has been hindered due to lack of immunological reagents. In the current report, we have used a polyclonal antibody specific for 13-(S)-HODE to detect this bioactive lipid for the first time in human prostate adenocarcinoma specimens (PCa) and the prostate cancer cell lines LNCaP and PC-3 by enzyme immunoassay. In addition, we have verified-the quantitation of 13-HODE by chiral-phase HPLC and examined the levels of lipoxygenase expression by Western, Northern, and RT-PCR analysis. Immunohistochemically detectable 13-HODE was observed in human PCa, whereas adjacent normal tissue showed no immunoreactivity. The presence of 15 lipoxygenase was evident by Western and RT-PCR analysis in both LNCaP and PC-3 cells, while Northern blot analysis showed the presence of 15-lipoxygenase message in LNCaP cells but failed to detect any 15-lipoxygenase message in PC-3 cells. In contrast, quantitation of 13-HODE by enzyme immunoassay and chiral phase HPLC showed significant levels of the compound in PC-3 cells but minimal enzymatically produced 13-HODE in LNCaP cells. These data provide a link between linoleic acid metabolism and the development or progression of prostate cancer. PMID- 9367846 TI - Fas/Fas ligand interaction regulates cytotoxicity of CD4+ T cells against staphylococcal enterotoxin B-pulsed endothelial cells. AB - Infiltration of activated CD4+ T cells and apoptosis of endothelial cells are present in the synovium of rheumatoid arthritis (RA). Using staphylococcal enterotoxin B (SEB) as an antigen, we examined the possible role of antigen (Ag) dependent activation of CD4+ T cells by endothelial cells, in inducing endothelial cell apoptosis. The human endothelial cell line, EA.hy926 cells, was cultured with or without interferon-gamma (IFN-gamma) and further incubated with CD4+ T cells in the presence or absence of SEB. After this cocultivation, the cytotoxicity and Fas ligand (FasL) expression of CD4+ T cells were examined. A small percentage of EA.hy926 cells expressed HLA-DR and -DQ, and this expression was significantly augmented after IFN-gamma stimulation. Anti-Fas IgM-induced apoptosis was exhibited by both unstimulated and IFN-gamma-stimulated EA.hy926 cells. Cytotoxicity of CD4+ T cells toward SEB-pulsed unstimulated EA.hy926 cells was detected. Furthermore, when CD4+ T cells were incubated with IFN-gamma stimulated, SEB-pulsed EA.hy926 cells with augmented HLA-DR and -DQ expression, this cytotoxicity was more significant. The addition of anti-HLA-DR and -DQ monoclonal antibodies (mAbs) or human Fas chimeric protein (hFas-Fc) reduced the cytotoxicity. FasL expression was induced in CD4+ T cells cocultured with SEB pulsed EA.hy926 cells, especially when the EA.hy926 cells were IFN-gamma stimulated. Furthermore, the addition of mAbs against CD54 and CD58 inhibited both the cytotoxicity and FasL expression of CD4+ T cells induced by SEB-pulsed EA.hy926 cells, indicating the importance of costimulatory molecules on EA.hy926 cells in activating CD4+ T cells. Our results suggest that CD4+ T cells are activated by endothelial cells in an Ag-dependent manner and subsequently express FasL, which induces Fas-mediated apoptosis of endothelial cells. This phenomenon may counteract the growth of RA synovium by inhibiting the proliferation of endothelial cells. PMID- 9367847 TI - Site and significance of cysteine residues in xylose reductase from Neurospora crassa as deduced by fluorescence studies. AB - Inactivation of xylose reductase (XR) by p-hydroxy-mercury benzoate (PHMB) was found to be biphasic with second-order rate constants of 80 and 6 M-1s-1 for the fast (kf) and slow (ks) phase respectively. Spectroscopic studies indicated that the inactivation was due to modification of one Cys residue per molecule of XR and not due to subsequent disruption of the quaternary structure. The binding of NADPH to XR (Kd 0.9 microM) was depressed on modification of the enzyme by PHMB (Kd 2.3 microM). The dependence of PHMB induced inactivation of XR in the presence of alcohols and varying temperature revealed that the Cys residue is situated in a hydrophobic microenvironment and is not involved in hydrogen bonding. Our present investigation using o-phthalaldehyde (OPTA) as the chemical initiator for fluorescent chemo-affinity labeling and double inhibition studies indicates that Cys residues involved in the reaction with PHMB (SHI) and OPTA (SHII) are distinctly different. Experimental evidence presented here serves to implicate that SHI located in a hydrophobic microenvironment at the high affinity NADPH binding site of XR plays a role in the binding of the coenzyme to XR, whereas SHII serves to maintain the conformation of the active site essential for catalysis by interacting with the NH2 group of an essential lysine residue. PMID- 9367848 TI - Alternative splicing of the primary Fas transcript generating soluble Fas antagonists is suppressed in the failing human ventricular myocardium. AB - Apoptosis of cardiomyocytes has been proposed as a factor contributing to severe heart failure. Since the trigger for apoptotic cellular suicide in nonischemic myocardium is unknown, we analyzed in human myocardial tissue the expression of the apoptosis-inducing membrane receptor Fas/APO-1 and of its alternatively spliced soluble isoforms which antagonize Fas by binding of the Fas ligand. Using reverse transcription polymerase chain reaction (RT-PCR) we found mRNA for Fas and 5 isoforms in nonfailing left ventricles, whereas Fas and only one isoform (FasExo6Del) were detectable in failing left ventricles. Standard calibrated, competitive RT-PCR revealed no significant increase of Fas mRNA in failing compared to nonfailing ventricles. However, the mRNA for FasExo6Del, expressed nearly on the same level as Fas in nonfailing ventricles, was decreased about 3 fold in failing ventricles. We propose that this altered expression of the Fas system renders the myocardium more susceptible for Fas-mediated apoptosis in end stage heart failure. PMID- 9367849 TI - Interaction of phagocytes with apoptotic cells leads to production of pro inflammatory cytokines. AB - It is generally believed that apoptosis is not associated with inflammation. To explore the possibility that the interaction of phagocytes with apoptotic cells provides a negative or null signal for inflammation, we examined the cytokine production by thioglycollate-induced peritoneal exudate cells (PEC) upon interaction with a murine T cell clone (CTLL-2) cultured in the absence of interleukin-2 (IL-2). Coculturing of PEC with apoptotic CTLL-2 cells led to the production of not only anti-inflammatory cytokines but also pro-inflammatory ones, notably MIP-2, at the mRNA level, and neutrophils were accumulated in vivo in response to the culture supernatant. Our findings suggest the possibility that apoptosis may be associated with leukocyte infiltration in vivo in some situations. PMID- 9367850 TI - Interleukin-1 modulates protein tyrosine phosphatase activity and permeability of brain endothelial cells. AB - Interleukin-1 alpha (IL-1 alpha) and interleukin-6 (IL-6), both known to be able to open the blood-brain barrier (BBB), downregulated plasma membrane-associated tyrosine phosphatase activity in primary porcine brain endothelial cells (PBEC). In contrast, transforming growth factor beta (TGF-beta) upregulated PTP activity and tumor necrosis factor alpha (TNF-alpha) had no effect. Plasma membrane associated PTP activity of PBEC was upregulated at contact inhibited growth arrest. Tightly confluent cells reduced 3H-inulin permeability by 34% compared with just confluent cells indicating the formation of barrier properties. The decrease in permeability temporally correlated with the elevated PTP activity of the cells at growth arrest and was reversed to control by IL-1 alpha. Vanadate, a broad-specificity PTP inhibitor, also enhanced 3H-inulin permeability. These data suggest that IL-1 alpha-induced endothelial permeability could be controlled through lowering PTP activity. PMID- 9367851 TI - Cloning and sequencing of aspartate aminotransferase from Thermus aquaticus YT1. AB - A 39-base oligonucleotide "guessmer" probe, based on partial N-terminal sequence analysis of the aspartate aminotransferase purified from Thermus aquaticus strain YT1, was used to screen a genomic library prepared from T. aquaticus DNA. A 1842 bp DNA fragment was isolated that proved to contain the coding sequence for the aspartate aminotransferase. The gene is 1152 bases long and codes for a protein of 383 amino acid residues. The amino acid sequence obtained showed 88.7%, 45.1% and 32.9% identity of sequence with those of thermostable aspartate aminotransferases from T. thermophilus, Bacillus YM2, and Sulfolobus solfataricus, respectively. It showed 39.1% identity with one of the gene products tentatively identified as aspartate aminotransferase from the methanogenic archaebacterium Methanococcus jannaschii. Neither the amino acid compositions nor the aligned amino acid sequences provides any obvious clue as to the origin of thermal stability in this group of enzymes. PMID- 9367852 TI - Enzymatic properties and effect of ionic strength on periplasmic nitrate reductase (NAP) from Desulfovibrio desulfuricans ATCC 27774. AB - Some sulfate reducing bacteria can induce nitrate reductase when grown on nitrate containing media being involved in dissimilatory reduction of nitrate, an important step of the nitrogen cycle. Previously, it was reported the purification of the first soluble nitrate reductase from a sulfate-reducing bacteria Desulfovibrio desulfuricans ATCC 27774 (S.A. Bursakov, M.-Y. Liu, W.J. Payne, J. LeGall, I. Moura, and J.J.G. Moura (1995) Anaerobe 1, 55-60). The present work provides further information about this monomeric periplasmic nitrate reductase (Dd NAP). It has a molecular mass of 74 kDa, 18.6 U specific activity, KM (nitrate) = 32 microM and a pHopt in the range 8-9.5. Dd NAP has peculiar properties relatively to ionic strength and cation/anion activity responses. It is shown that monovalent cations (potassium and sodium) stimulate NAP activity and divalent (magnesium and calcium) inhibited it. Sulfate anion also acts as an activator in KPB buffer. NAP native form is protected by phosphate anion from cyanide inactivation. In the presence of phosphate, cyanide even stimulates NAP activity (up to 15 mM). This effect was used in the purification procedure to differentiate between nitrate and nitrite reductase activities, since the later is effectively blocked by cyanide. Ferricyanide has an inhibitory effect at concentrations higher than 1 mM. The N-terminal amino acid sequence has a cysteine motive C-X2-C-X3-C that is most probably involved in the coordination of the [4Fe-4S] center detected by EPR spectroscopy. The active site of the enzyme consists in a molybdopterin, which is capable for the activation of apo-nit-1 nitrate reductase of Neurospora crassa. The oxidized product of the pterin cofactor obtained by acidic hidrolysis of native NAP with sulfuric acid was identified by HPLC chromatography and characterized as a molybdopterin guanine dinucleotide (MGD). PMID- 9367854 TI - Expression of telomerase RNA, telomerase activity, and telomere length in human gliomas. AB - To understand the mechanisms of telomere maintenance in human gliomas, telomerase activity, telomerase RNA expression and telomere length of surgically excised glioma samples were analyzed. Sixty-five percent of gliomas exhibited telomerase activity, the occurrence of which was not related to their histological malignancy scale. Not only the telomerase-positive gliomas, but also the telomerase-negative gliomas and normal brain expressed telomerase RNA, suggesting that the presence of telomerase RNA component does not indicate the presence of telomerase activity. Compared with telomerase-positive gliomas, telomerase negative gliomas had long heterogeneous telomeric terminal restriction fragments. These data suggest that in addition to the telomerase-dependent mechanism, a telomerase-independent mechanism for telomere maintenance may be present in human gliomas. PMID- 9367853 TI - Induction of ubiquitin conjugating enzyme activity for degradation of topoisomerase II alpha during adenovirus E1A-induced apoptosis. AB - Topoisomerase (topo) II alpha is degraded via polyubiquitination during adenovirus E1A-induced apoptosis in MA1 cells, a derivative of the human epidermoid carcinoma cell line KB. Topo II alpha ubiquitination activity in MA1 cells increased nearly 10-fold after induction of E1A in response to dexamethasone. To identify a topo II alpha ubiquitination factor(s), the S100 fractions prepared from apoptosis-induced (42 h) and uninduced (0 h) MA1 cells were first fractionated by ubiquitin-Sepharose columns. The ubiquitination activity induced by E1A was predominantly eluted with 20 mM AMP. Further fractionation of the AMP eluates on Resource-Q columns and the thiolester formation of the proteins resolved by electrophoresis with biotinylated ubiquitin revealed that a species of E2 isozyme recovered in the QFT2 fraction increased markedly in MA1 cells after E1A expression. These results indicate that a ubiquitination factor(s) specific to topo II alpha is induced during E1A-induced apoptosis in MA1 cells. PMID- 9367855 TI - Isolation of ALU1-P gene encoding a protein with aluminum tolerance activity from Arthrobacter viscosus. AB - We isolated a DNA fragment (ALU1-P) encoding a protein with an activity of aluminum tolerance from an Al tolerant soil microorganism, Arthrobacter viscosus. This microorganism was isolated from acidic tea field soils. The cloned DNA is composed of 1090 nucleotides, which has one open-reading frame without any stop codon. However, when the DNA fragment was transferred into Escherichia coli, a microorganism susceptible to Al toxicity, it endowed E. coli with Al tolerance. The deduced amino acid sequence of the DNA showed 65% identity with the protein of YbaX gene in Escherichia coli, and 51.1% identity with YB91 Haein hypothetical protein of HI1191 gene in Haemophilus influenzae. The ALU1-P gene in the expression vector produced a protein of 192 amino acids deriving a molecular weight of 21.3 kDa by using the stop codon in vector. The ALU1-P gene is a new one that has the characteristic of Al tolerance. PMID- 9367856 TI - Hypoxia and hypoxia/reoxygenation activate p65PAK, p38 mitogen-activated protein kinase (MAPK), and stress-activated protein kinase (SAPK) in cultured rat cardiac myocytes. AB - We previously reported that both hypoxia and hypoxia followed by reoxygenation (hypoxia/reoxygenation) rapidly activate Src family tyrosine kinases and p21ras in cultured rat cardiac myocytes. This was followed by the sequential activation of mitogen-activated protein kinase kinase kinase (MAPKKK) activity of Raf-1, MAP kinase kinase (MAPKK), MAPKs (p44mapk and p42mapk, also called extracellular signal-regulated protein kinase [ERK]1 and ERK2, respectively), and S6 kinase (p90rsk). In this study, we demonstrated that both hypoxia and hypoxia/reoxygenation caused rapid activation of stress-activated MAPK signaling cascades involving p65PAK, p38MAPK, and SAPK. These stimuli also caused phosphorylation of activating transcription factor (ATF)-2. Because p65PAK is known to be upstream of p38MAPK and also be a target of p21rac-1, which belongs to the rho subfamily of p21ras-related small GTP-binding proteins, these results strongly suggested that two different stress-activated MAPK pathways distinct from the classical MAPK pathway were activated in response to hypoxia and hypoxia/reoxygenation in cardiac myocytes. PMID- 9367857 TI - Identification of a novel, tissue-specific calpain htra-3; a human homologue of the Caenorhabditis elegans sex determination gene. AB - We cloned a novel human gene encoding a tissue-specific calpain, termed htra-3, which is highly homologous to the tra-3 sex determination gene of Caenorhabditis elegans. The predicted htra-3 polypeptide had similarity to the calpain large subunits in domain organization throughout domains I to III, but the sequences of domain IV lacked calcium-binding motifs. Northern blot analysis revealed high expression in the colon, small intestine and testis. Radiation hybrid mapping localized the htra-3 gene to chromosome 11q14 (2.53cR apart from WI-3895). Western blot analysis demonstrated that the approximately 73-kDa htra-3 protein was transiently expressed in COS-7 cells. These observations, together with the genetic information in C.elegans, suggest a unique function for htra-3 protein. PMID- 9367858 TI - Quercetin inhibits heat shock protein induction but not heat shock factor DNA binding in human breast carcinoma cells. AB - The flavonoid quercetin inhibits the heat-induced synthesis of heat shock proteins (hsps) in a variety of cell lines. To determine whether quercetin could inhibit hsp expression in breast cancer cells, we used the human breast cancer cell line, MDA-MB-231. Treatment of these cells with quercetin decreased the heat induced synthesis of hsp27 and hsp70. However, inhibition of hsp expression did not correspond with the reduced ability of heat shock transcription factors (HSFs) to bind DNA. Furthermore, while quercetin treatment inhibited HSF2 expression, it only slightly affected HSF1 expression in breast cancer cells. In contrast, quercetin inhibited both HSF DNA-binding activity and HSF expression in HeLa cells. Our studies suggest that quercetin's action is cell-type specific, and in breast cancer cells may involve regulation of HSF transcriptional activity, rather than regulation of its DNA-binding activity. PMID- 9367859 TI - Characterisation of bovine peroxisome proliferator-activated receptors gamma 1 and gamma 2: genetic mapping and differential expression of the two isoforms. AB - In this report we describe the isolation and characterisation of the cDNAs encoding two isoforms of peroxisome proliferator-activated receptor gamma (PPAR gamma), gamma 1 and gamma 2, in cattle. The cDNA sequences show strong conservation with the corresponding sequences reported in other species. The distribution of PPAR gamma mRNAs in various bovine tissues was investigated using Northern blot analysis. The highest expression was detected in adipose tissue with about equal amounts of the both transcripts while a differential expression was found in other tissues investigated. PPAR gamma 1 was expressed at relatively high levels in bovine spleen and lung and to a lower extent in ovary, mammary gland, and small intestine. The amount of PPAR gamma 2 was apparently lower than that of PPAR gamma 1 in spleen, lung, and ovary. These results indicate a modulation of tissue distribution for the two transcripts in cattle. Using genetic linkage analysis we have also assigned the PPAR gamma gene to bovine chromosome 22. PMID- 9367860 TI - Inhibitory effect of selenium on biliary secretion of methyl mercury in rats. AB - The inhibitory effect of sodium selenite on biliary secretion of methyl mercury was examined in rats. The biliary secretion of methyl mercury in rat treated with 1 mumol/kg of methyl mercury was significantly decreased by administration of selenite at doses of 0.05 mumol/kg or higher. In rats given 10 mumol/kg of methyl mercury, marked depression of biliary secretion of mercury was observed when selenite was injected at a dose of 0.2 mumol/kg. On the other hand, secretion of substantial amounts of selenium was observed when biliary secretion of mercury was depressed. When the concentration of selenium in the bile was higher than 5 nmol/ml, biliary secretion of mercury was markedly depressed independently of the dose of methyl mercury administered (1 mumol/kg or 10 mumol/kg). These results suggest that the degree of inhibitory effect of selenite may be determined by the selenium concentration in the liver or the bile after treatment with selenite rather than the molar ratio of the dose of methyl mercury and selenite. We concluded that the decrease in biliary secretion of methyl mercury induced by selenite may result from inhibition of pathway for secretion of methyl mercury from liver to bile rather than the direct formation of a complex between methyl mercury and selenium. Methyl mercury has been considered to be secreted from liver to bile as a complex with glutathione (GSH). However, administration of selenite did not affect biliary secretion of GSH or hepatic glutathione S transferase activity. Moreover, gel filtration of liver cytosol demonstrated that the distribution pattern of hepatic methyl mercury between macromolecules and GSH was not significantly changed by administration of selenite. These results suggest that selenite does not affect complex formation of methyl mercury with GSH at least in the liver. Selenite might specifically inhibit the activity of the canalicular transporter(s) which transport complexes of methyl mercury and GSH from the liver to bile. PMID- 9367862 TI - S-nitrosohemoglobin in the fetal circulation may represent a cycle for blood pressure regulation. AB - It has recently been demonstrated, in rats, that hemoglobin transports nitric oxide (NO), as S-nitrosocysteine, from the lungs to the peripheral tissues. This cycle may be involved in the regulation of blood pressure and efficient delivery of oxygen in adult animals. We sought to determine whether this model was applicable to the human fetus. Umbilical cord blood was obtained from deliveries between 37 and 42 weeks of gestation (n = 19). NO, released from erythrocyte s nitrosohemoglobin (SNO-Hb), was determined by the Saville reaction and total plasma NO was determined by the Greiss reaction. SNO-Hb levels were found to be higher in the umbilical vein, [SNO]/[Hb] = 2.19 +/- 1.22 (X10(-3)), than in the artery, [SNO]/[Hb] = 1.45 +/- 0.66 (X10(-3)) (P < 0.001, Wilcoxon Signed Rank test). This supports the hypothesis that fetal blood pressure may be regulated by erythrocytes acting via a hemoglobin-based mechanism. PMID- 9367863 TI - Novel splicing of an IGF2 polymorphic region in human adrenocortical carcinomas. AB - The human IGF2 gene lies on chromosome 11p15.5 and encodes for a mitogenic peptide. IGF2 is often overexpressed in many tumours including adrenal carcinomas. In this study while screening 12 adrenocortical carcinomas for heterozygosity at the Apa I and (CA)n repeat polymorphisms we observed a novel splicing event in two samples which showed both an allelic expression imbalance and preferential splicing for one of the alleles. Further examination revealed that the splicing was not confined to one particular site. Three of such splice products were isolated and cloned. Using RNase protection analysis the presence of this splicing event was demonstrated for both adrenocortical carcinoma samples and also in a Hep3B cell line. This suggested that the event may be occurring in all the samples. The presence of this splicing was then confirmed in all 12 adrenocortical carcinoma samples by PCR. These data suggest that the splicing event may be a general feature for IGF2 transcripts. PMID- 9367861 TI - The generation of 1H-NMR-detectable mobile lipid in stimulated lymphocytes: relationship to cellular activation, the cell cycle, and phosphatidylcholine specific phospholipase C. AB - Mobile lipids detected using 1H-NMR in stimulated lymphocytes were correlated with cell cycle phase, expression of the interleukin-2 receptor alpha and proliferation to assess the activation status of the lymphocytes. Mobile lipid levels, IL-2R alpha expression and proliferation increased after treatment with PMA and ionomycin. PMA or ionomycin stimulation alone induced increased IL-2R alpha expression but not proliferation. PMA- but not ionomycin-stimulation generated mobile lipid. Treatment with anti-CD3 antibody did not increase IL-2R alpha expression or proliferation but did generate increased amounts of mobile lipid. The cell cycle status of thymocytes treated with anti-CD3, PMA or ionomycin alone indicated an accumulation of the cells in the G1 phase of the cell cycle. The generation of mobile lipid was abrogated in anti-CD3 antibody stimulated thymic lymphocytes but not in splenic lymphocytes, using a phosphatidylcholine-specific phospholipase C (PC-PLC) inhibitor which blocked cells in the G1/S phase of the cell cycle. This suggests that the 1H-NMR detectable mobile lipid may be generated in anti-CD3 antibody-stimulated thymic lymphocytes by the action of PC-PLC activity via the catabolism of PC, in the absence of classical signs of activation. PMID- 9367864 TI - Construction and enhanced cytotoxicity of a [cyanovirin-N]-[Pseudomonas exotoxin] conjugate against human immunodeficiency virus-infected cells. AB - Cyanovirin-N (CV-N) is a novel 11-kDa anti-HIV(human immunodeficiency virus) protein that binds with high affinity to the viral envelope glycoprotein gp120. In contrast to soluble CD4 and most known neutralizing antibodies that bind gp120, CV-N exerts potent anti-viral activity against primary clinical HIV isolates as well as laboratory-adapted strains of HIV. Here we describe the recombinant production, purification, and characterization of a chimeric toxin molecule, FLAG-CV-N-PE38, that contains CV-N as a gp120-targeting moiety linked to the translocation and cytotoxic domains of Pseudomonas exotoxin A. FLAG-CV-N PE38 showed enhanced cytotoxicity to HIV-infected, gp120-expressing H9 cells compared to uninfected H9 cells. Competition experiments with free CV-N provided further support that the enhanced FLAG-CV-N-PE38-induced cytotoxicity was due to interactions of the CV-N moiety with cell surface gp120. This study establishes the feasibility of use of CV-N as a gp120-targeting sequence for construction and experimental therapeutic investigations of unique new chimeric toxins designed to selectively destroy HIV-infected host cells. PMID- 9367866 TI - Six novel transcripts that remove a huge intron ranging from 250 to 800 kb are produced by alternative splicing of the 5' region of the dystrophin gene in human skeletal muscle. AB - The dystrophin gene, which is mutated in patients with Duchenne and Becker muscular dystrophies, comprises 79 exons and is thus the largest known human gene. A full spectrum of splicing of dystrophin transcript has not been elucidated yet. In this study, 6 novel alternative splicing reactions were discovered in the 5' region by amplifying the cDNA corresponding to exons M1 through 18. Two of these novel transcripts maintain the translational reading frame and are presumed to produce truncated dystrophin, while the other four have disrupted reading frames. The physical distance between splice donor and acceptor sites ranged from 250 kb to 800 kb. Furthermore, the same six alternative splicing products were obtained from mouse skeletal muscle cDNA. This indicated that these novel alternative splicing events are conserved in humans and mice. PMID- 9367865 TI - Adenovirus-mediated gene transfer of C-type natriuretic peptide causes G1 growth inhibition of cultured vascular smooth muscle cells. AB - We have proposed the "vascular natriuretic peptide system", in which C-type natriuretic peptide (CNP), the third member of the natriuretic peptide family, can control vascular tone and growth as an endothelium-derived relaxing peptide. We aimed at overexpression of CNP gene in vascular smooth muscle cells (SMCs) by adenovirus-mediated gene transfer to examine the growth characteristics of SMCs via the augmentation of cGMP production. Rat aortic SMCs infected with Ad.CNP, a replication-deficient adenovirus driving rat CNP cDNA, produced 162 +/- 55 fmol/mL of CNP, which was 4,000 times higher than that produced by endothelial cells. cGMP production was also augmented in Ad.CNP-infected SMCs (2200 +/- 270 fmol/10(4) cells). Accordingly, significant growth inhibition was observed in SMCs infected with Ad.CNP. The flow cytometry analysis revealed that the population of the S and G2 + M phases was reduced by 60% of the control in Ad.CNP infected SMCs. The gene expression of ANP-B receptor, which is expressed abundantly in SMCs with the synthetic phenotype, was suppressed in Ad.CNP infected SMCs, while the gene expression of ANP-A receptor, which is expressed predominantly in SMCs with the contractile phenotype, became detectable in Ad.CNP infected SMCs. In addition, the gene expression of smooth muscle myosin heavy chain-2 (SM-2), which is the molecular marker of highly-differentiated SMCs, was also induced in Ad.CNP-treated SMCs. These results suggest that cGMP cascade activation induces re-differentiation of SMCs. The present study demonstrated that overexpression of CNP induced growth inhibition of SMCs at the G1 phase with possible alteration of the phenotype. PMID- 9367867 TI - The Ras antagonist S-farnesylthiosalicylic acid induces inhibition of MAPK activation. AB - Inhibition of Ras-dependent signaling and of oncogenic Ras function by farnesyl transferase inhibitors that block Ras membrane anchorage is limited due to alternative prenylation of Ras. Here we demonstrate that inhibition of the Ras dependent Raf-1-MAPK (mitogen activated protein kinase) cascade is achieved by S farnesylthiosalicylic acid (FTS) which affects Ras membrane association but not Ras farnesylation. FTS interferes with the activation of Raf-1 and MAPK and inhibits DNA synthesis in Ras-transformed EJ cells at concentrations similar to those at which it inhibits EJ cell growth (5-25 microM). FTS also inhibits MAPK activity and DNA synthesis stimulated by serum, EGF or thrombin in serum-starved untransformed Rat-1 cells, demonstrating the generality of its effects on Ras dependent signaling. The effects of FTS on MAPK activity developed relatively rapidly (within 2-6 h) consistent with its rapid effect on Ras membrane anchorage. FTS represents a new class of Ras antagonists that may be useful for the inhibition of various types of oncogenic Ras isoforms independently of their prenylation. PMID- 9367868 TI - Molecular cloning and characterization of the mouse apoptosis signal-regulating kinase 1. AB - The mouse cDNA for apoptosis signal-regulating kinase 1 (ASK)1 was isolated. The overall amino acid sequence identity between the mouse and the human ASK1 was 91.9%. A database search revealed that the kinase domain of ASK1 is evolutionally well-conserved over species among nematode, fly, mouse and human. Northern blot analysis identified a 6-kb transcript of ASK1 which is expressed in the various mouse adult tissues including heart, brain, lung, liver and kidney. Immunohistochemical analysis of mouse embryos (17 days post coitum) revealed a localized expression of ASK1 in developing skin, cartilage and bone, suggesting a possible role for ASK1 in tissue development during embryogenesis as well as cytokine-induced apoptosis. PMID- 9367869 TI - Expression of Wnt5a is downregulated by extracellular matrix and mutated c-Ha-ras in the human mammary epithelial cell line MCF-10A. AB - Wnt genes are involved in tumour growth and regulate cell adhesion. Some (Wnt5a and Wnt7b) are more highly expressed in human breast cancer compared to normal tissues. Wnt5a is involved in the regulation of cell movement in Xenopus and is upregulated in several human cancers. Factors regulating Wnt gene expression in human breast epithelium are poorly understood, but c-erbB2 is amplified in many breast cancers and associated with rapid growth and metastasis, as is high expression of c-Ha-ras. To further understand the regulation of Wnt gene expression, this study investigated the effect of proto-oncogenes c-Ha-ras and c erbB2, and collagen on Wnt mRNA expression, in a normal spontaneously immortalised human mammary epithelial cell line MCF-10A. Out of nine human Wnt genes investigated, Wnt5a and Wnt7b were expressed in the parental cell line, and neomycin-, c-Ha-ras- and c-erbB2-transfected cell lines. The level of Wnt5a mRNA expression was decreased 40-fold and 3-fold when parental cells were grown on collagen and in collagen, respectively. This downregulation correlated with cell branching. However, Wnt7b was not regulated by collagen. In the presence of activated c-Ha-ras, the level of Wnt5a mRNA expression was markedly decreased (> 200-fold) and cell growth rate was elevated. When treated with p21ras inhibitor, BZA-5B, there was a moderate reversal of Wnt5a mRNA expression (2-fold) with a parallel decrease in cell growth. The data indicate that c-Ha-ras is an upstream inhibitory regulator of Wnt5a, and provide further evidence of an inverse relationship between Wnt5a mRNA expression and cell branching. This demonstrates selectivity of regulation of individual members of the Wnt gene family by the ras pathway. Overexpression of c-erbB2 had no effect on Wnt5a or Wnt7b mRNA expression. Thus, extracellular matrix and ras regulate Wnt5a, providing a mechanism for feedback of morphogenetic movements, which is relevant also to cancer biology. PMID- 9367870 TI - The conformation formed by the domain after alanine-155 induces inversion of aspartic acid-151 in alpha A-crystallin from aged human lenses. AB - A new cleavage site, which is a post-translational modification, was found between residues His-154 and Ala-155 in alpha A-crystallin from the aged human lens. After trypsin digestion of alpha A-crystallin two peptides that include Asp 151 were obtained and have remarkable differences. That is, the stereo configuration of the Asp-151 in the normal length peptide was predominately inverted to the D-isomer of beta-aspartyl form (D/L of 5.7). However, the stereoconfiguration of the Asp-151 in the cleavage peptide, that lacks the sequence following Ala-155 to the C-terminus, remained predominately in the L isomer form as indicated by a D/L value of 0.3. The results suggest that the secondary structure in the region of Ala-155 to the C-terminus may constitute a field that causes the inversion of the Asp-151 to the D-isomer form. Since this kind of cleavage was not found in alpha A-crystallin from young lens, the cleavage between His-154 and Ala-155 is probably the result of aging. PMID- 9367871 TI - Structure of detergent-resistant membrane domains: does phase separation occur in biological membranes? AB - Detergent-resistant membrane domains (DRMs) can be isolated from a variety of eukaryotic cells. DRMs are of interest because of their potential importance in processes such as intracellular membrane sorting, and signal transduction at the cell surface. One type of DRM is also present in caveolae, non clathrin-coated plasma membrane pits with proposed roles in endocytosis, lipid transport, and signal transduction. Here we review recent advances in understanding the structure of these domains, and explore the possibility that DRMs are present in a phase separate from the surrounding bilayer. DRMs are rich in sphingolipids and cholesterol. The long saturated acyl chains and high acyl chain melting temperature of sphingolipids mediate their association in detergent resistant domains. These sphingolipid and cholesterol-rich domains have the properties of the liquid-ordered phase previously described in model membranes. Several lines of investigation support the idea that DRMs are not detergent-induced artifacts, but exist as domains in cell membranes. A striking feature of the proteins in DRMs is that many of them are linked to lipids. These include both GPI anchored proteins, and acylated proteins such as Src-family kinases. The linkage of these proteins to saturated acyl chains may help in targeting them to ordered membrane domains. Caveolin, the major structural protein of caveolae, is multiply palmitoylated. The presence of a high concentration of palmitate chains in DRMs in caveolae may help stabilize ordered domains. PMID- 9367872 TI - A novel RING finger protein, BFP, predominantly expressed in the brain. AB - RING finger is a variant zinc finger motif present in a new family of proteins including transcription regulators. A genomic DNA fragment containing RING finger motifs was identified by the polymerase chain reaction using degenerate primers. Using this fragment as a probe, we have isolated a novel cDNA from rat brain library. The predicted open reading frame contains a RING finger domain at its N terminal portion. The corresponding transcript was detected predominantly in the brain and therefore was designated brain finger protein (bfp). An antibody raised against a recombinant bfp reveals the presence of the bfp in the brain. Interestingly, the bfp is induced during retinoic acid-mediated differentiation of P19 embryonal carcinoma cells into neural cells. These findings suggest the possible involvement of bfp in some aspects of neural cell regulation. PMID- 9367873 TI - Translation of ODC mRNA and polyamine transport are suppressed in ras-transformed CREF cells by depleting translation initiation factor 4E. AB - Rapid tumor growth and metastasis require increased polyamine metabolism, which is coordinately regulated by ornithine decarboxylase (ODC) and the polyamine transporter. Both activities are stimulated by ras signalling and are dependent upon protein biosynthesis. T24ras oncogene expression in rat embryo fibroblasts (CREFT24) induces cellular transformation and malignancy, in part, by stimulating the rate-limiting translation initiation factor, eIF-4E. CREFT24 expressing antisense RNA to eIF-4E (AS4E) have markedly decreased tumor growth rates and metastatic capacity, without altered monolayer growth rates. Herein, we demonstrate that in AS4E, ODC is translationally suppressed resulting in decreased ODC activity. Additionally, exogenous polyamine uptake is suppressed in AS4E cells indicating that AS4E can neither generate nor import the polyamines necessary to support rapid tumor growth. These data provide evidence that eIF-4E is the link between ras-induced malignancy and increased polyamine metabolism and support the hypothesis that eIF-4E plays a pivotal role in mediating ras-induced malignancy. PMID- 9367874 TI - Basic fibroblast growth factor induces apoptosis in myofibroblastic cells isolated from rat palatal mucosa. AB - The effect of basic fibroblast growth factor (bFGF) on apoptosis in normal rat palatal fibroblasts and rat palatal scar fibroblasts was examined by the TUNEL method in order to clarify the mechanism of apoptosis induction in myofibroblasts during the scar formation process. A percentage of scar fibroblasts undergoing apoptosis was significantly higher than that of palatal fibroblasts when they were treated with bFGF succeeding to serum starvation. Palatal fibroblasts, phenotypically modulated into myofibroblasts by the pretreatment with transforming growth factor-beta 1 (TGF-beta 1), similarly showed a higher level of apoptosis induction by bFGF-treatment. TGF-beta 1 elevated protein and mRNA level of FGF receptor (FGFR) in palatal fibroblasts. Tyrosine autophosphorylation of FGFR upon stimulation by bFGF was significantly higher in scar fibroblasts than in normal palatal fibroblasts. These findings suggested that bFGF may be a potential stimulator of apoptosis in myofibroblasts during palatal scar formation and that FGFR may be responsible for this process. PMID- 9367875 TI - Imprinting of lyophilized alpha-chymotrypsin affects the reactivity of the active site imidazole. AB - Iodomethane reacted in vacuo with lyophilized alpha-chymotrypsin to give an inactive enzyme in which the active-site imidazole was dimethylated. However, alpha-chymotrypsin co-lyophilized with the competitive inhibitors, N-acetyl-L tryptophan or N-acetyl-D-tryptophan, was fully protected from such inactivation. In contrast, indole by itself not only did not protect the lyophilized enzyme from inactivation by iodomethane but also increased the rate of inactivation. The lyoprotectants citrate or sorbitol also showed opposite effects when co lyophilized with alpha-chymotrypsin. Citrate protected the lyophilized enzyme from inactivation, while bound sorbitol dramatically accelerated the inactivation. Imprinting of lyophilized alpha-chymotrypsin with indole or sorbitol increased the reactivity of the active-site histidine towards iodomethane. Co-lyophilization of alpha-chymotrypsin with appropriate ligands is known to increase significantly its enzymatic activity in hydrophobic organic solvents. It is proposed that this imprinting phenomenon arises because a greater proportion of the active-sites in the lyophilized enzyme are in a catalytically favorable conformation where the imidazole of His-57 is more strongly hydrogen bonded to the carboxylate of Asp-102. PMID- 9367876 TI - The monocyte chemotactic protein-4 induces oxygen radical production, actin reorganization, and CD11b up-regulation via a pertussis toxin-sensitive G-protein in human eosinophils. AB - The novel human CC-chemokine monocyte chemotactic protein-4 (MCP-4) is a chemotaxin for eosinophils. Here, the biological activities and the activation profile of MCP-4 was further characterized in eosinophils and compared to other activators such as platelet activating factor (PAF), Eotaxin and RANTES. As demonstrated by lucigenin-dependent chemiluminescence and superoxide dismutase inhibitable cytochrome C reduction MCP-4 stimulated the production of reactive oxygen metabolites. Furthermore, MCP-4 induced up-regulation of the integrin CD11b. Flow cytometric studies revealed rapid and transient actin polymerization upon stimulation with MCP-4. At optimal concentrations the changes induced by MCP 4 were weaker than the effects after stimulation with PAF and comparable to those obtained by RANTES and Eotaxin. Cell responses elicited by MCP-4 were inhibited by pertussis toxin indicating involvement of Gi-proteins in this signal pathway. These findings point to a role of MCP-4 in the pathogenesis of eosinophilic inflammation as chemotaxin as well as activator of pro-inflammatory effector functions. PMID- 9367877 TI - KDEL receptor expression is not coordinatedly up-regulated with ER stress-induced reticuloplasmin expression in HeLa cells. AB - Perturbation of the normal functioning of the endoplasmic reticulum (ER) increases the expression of lumenal proteins, such as grp78, and calreticulin. These proteins are retained within the compartment by a salvage mechanism involving the recognition of a C-terminal tetra-peptide sequence by the KDEL receptor. We have investigated whether disrupting normal ER function concomitantly increases the expression of the mRNAs encoding the two mammalian isoforms of the receptor, erd2.1 and erd2.2. Inhibition of N-linked glycosylation of proteins by tunicamycin had no effect upon the levels of the single mRNA species recognized by the erd2.1 probe, or the multiple transcripts detected with the erd2.2 cDNA probe. ER Ca2+ store depletion by thapsigargin did not increase erd2.1 mRNA, but actually caused a decrease in erd2.2 mRNA. Both thapsigargin, and tunicamycin, increased calreticulin secretion from the cells, although this might be due to more than simply saturation of KDEL receptor binding. PMID- 9367878 TI - Nucleotide sequence of the Pseudomonas sp. DJ77 phnG gene encoding 2 hydroxymuconic semialdehyde dehydrogenase. AB - The nucleotide sequence of a 1520 bp region, spanning the coding region for the meta-cleavage pathway enzyme, 2-hydroxymuconic semialdehyde dehydrogenase, was determined. This enzyme, encoded by the phnG, is the first of three sequential enzymes required for conversion of 2-hydroxymuconic semialdehyde, which is produced from catechol by the PhnE catechol 2,3-dioxygenase, to 2-hydroxypent-2,4 dienoate in the dehydrogenative branch of the pathway. The deduced protein sequence is 484 amino acid residues long with a M(r) of 51504. The phnG has a high degree of homology with genes encoding isofunctional proteins from other Pseudomonas strains. We now show that the relative position of the phnG dehydrogenase gene in the phn operon is unique compared to the other meta cleavage operons which have a dehydrogenative branch of the pathway. PMID- 9367880 TI - Characterization of gamma S-crystallin isoforms from lip shark (Chiloscyllium colax): evolutionary comparison between gamma S and beta/gamma crystallins. AB - gamma S-Crystallin from shark eye lenses, formerly termed beta s crystallin in mammalian lenses, is structurally characterized in this study by cDNA cloning and sequencing. To facilitate sequence characterization of gamma S-crystallin possessing intermediate structural properties between beta- and gamma crystallins, cDNA mixture was constructed from the poly(A)+ mRNA isolated from shark eye lenses, and amplification by polymerase chain reaction (PCR) was carried out to obtain nucleotide segments encoding multiple shark gamma S crystallins. Sequencing several positive clones revealed that a multiplicity of isoforms exists in the gamma S-crystallin class of this cartilaginous fish, similar to authentic gamma-crystallin family characterized from the same shark species. Comparison of protein sequences encoded by two representative shark gamma S1 and gamma S2 cDNAs with those published sequences of beta-, gamma-, and gamma S crystallins from bovine, human, bullfrog and carp lenses indicated that there is about 35-64% sequence homology between shark gamma S crystallins and structurally related crystallins from different evolutionary classes, with a higher sequence similarity between shark gamma S and mammalian gamma-crystallins than that of shark gamma S and carp gamma S or bovine gamma S crystallins. A phylogenetic tree constructed on the basis of the sequence divergence among various beta-, gamma-, and gamma S crystallins corroborates the closer relatedness of shark gamma S to authentic gamma-crystallin than to mammalian and teleostean gamma S crystallins. It further strengthens the supposition that ancestral precursors of gamma S-crystallins were present in the shark lens long before the appearance of present-day teleostean and mammalian gamma S crystallins. PMID- 9367879 TI - A c-Cbl yeast two hybrid screen reveals interactions with 14-3-3 isoforms and cytoskeletal components. AB - The protein product of c-cbl proto-oncogene is known to interact with several proteins, including Grb2, Crk and PI3 kinase, and is thought to regulate signalling by many cell surface receptors. The precise function of c-Cbl in these pathways is not clear, although a genetic analysis in Caenorhabditis elegans suggests that c-Cbl is a negative regulator of the epidermal growth factor receptor. Here we describe a yeast two hybrid screen performed with c-Cbl in an attempt to further elucidate its role in signal transduction. The screen identified interactions involving c-Cbl and two 14-3-3 isoforms, cytokeratin 18, human unconventional myosin IC, and a recently identified SH3 domain containing protein, SH3 P17. We have used the yeast two hybrid assay to localise regions of c-Cbl required for its interaction with each of the proteins. Interaction with 14 3-3 is demonstrated in mammalian cell extracts. PMID- 9367881 TI - Depletion of endoplasmic reticulum calcium stores protects against hypoxia- and mitochondrial inhibitor-induced cellular injury and death. AB - We have shown previously that intracellular Ca+2 chelation and calpain inhibitors block the influx of extracellular Ca+2 and Cl- during the late phase of cell injury in renal proximal tubules (RPT) exposed to the mitochondrial inhibitor antimycin A. Since the endoplasmic reticulum (ER) is the major intracellular Ca+2 storage site, ER Ca+2 release/depletion may mediate the Ca+2 influx and cell death. Treatment of RPT suspensions with thapsigargin, an ER Ca+2-ATPase inhibitor, increased cytosolic free Caf+2 (Ca+2) levels from 122 +/- 7 to 322 +/- 55 nM within 10 sec of addition followed by a return to control levels within 3 min. A 5-min pretreatment of RPT suspensions with thapsigargin blocked antimycin A- and hypoxia-induced influx of extracellular Ca+2 and Cl- and the resulting cell death/lysis. These data suggest that ER Ca+2 release/depletion during cell injury may trigger a signaling cascade that causes extracellular Ca+2 influx followed by Cl- influx, cell swelling, and ultimately cell death/ lysis. PMID- 9367882 TI - The antidiabetic agent thiazolidinedione stimulates the interaction between PPAR gamma and CBP. AB - The peroxisome proliferator-activated receptor (PPAR) gamma is a member of the nuclear hormone receptor family, which is predominantly expressed on adipocytes and considered to be involved in the process of adipogenesis. The new thiazolidinedione (TZD) compound, T-174, developed as an antidiabetic drug, stimulated the transcription of PPAR gamma and the adipocyte differentiation of 3T3-L1 cells. Interestingly, T-174 induced the interaction between PPAR gamma and CBP (cAMP response element binding protein (CREB) binding protein), a co-factor of various transcription regulators. CBP mRNA was expressed in both preadipocytes and adipocytes. These results suggest that CBP plays a role in the PPAR gamma mediated signaling pathway activated by TZD, including adipogenesis. PMID- 9367883 TI - Resonance Raman spectroscopy of soybean peroxidase. AB - Resonance Raman spectra (600-1700 cm-1) for the heme enzyme soybean peroxidase (Rz = 2.5) were obtained using Soret band excitation at 406.7 nm. The vibrational frequencies and depolarization data indicate a strong similarity between the active sites of soybean and horseradish peroxidase. This similarity suggests that the active site in the resting form of soybean peroxidase contains a ferric iron, is a high-spin 5-coordinate heme binding His as a fifth axial ligand. PMID- 9367884 TI - Mitochondrial dysfunction in lymphocytes from old mice: enhanced activation of the permeability transition. AB - Aging is associated with mitochondrial dysfunction in excitable tissues such as nerve and muscle. However, it is not known if immunosenescence is similarly associated with mitochondrial dysfunction in lymphocytes. We have found that spleen lymphocytes from old mice have lower respiration rates than lymphocytes from young mice. Cyclosporin, an inhibitor of the mitochondrial Permeability Transition, PT, restored normal respiration rates to lymphocytes from old mice, suggesting enhanced susceptibility to PT activation. Lymphocytes from old mice also had a lower mitochondrial membrane potential (delta psi m) than lymphocytes from young mice, which was also restored by cyclosporin. Oxidized FAD fluorescence was higher in lymphocytes from old mice suggesting a more oxidized state, which may be the cause of the enhanced activation of PT. Incubation of lymphocytes from old mice with the lipophilic cationic dye DiOC6(3), which inhibits electron transport, induced the appearance of apoptotic cells. These findings suggest that the mitochondrial PT is more susceptible to activation in lymphocytes from old mice. This activation may inhibit energy metabolism and enhance apoptosis, and may therefore contribute to immunosenescence. PMID- 9367885 TI - Characterization of the [NiFe] hydrogenase from the sulfate reducer Desulfovibrio vulgaris Hildenborough. AB - The [NiFe] hydrogenase from Desulfovibrio vulgaris Hildenborough was isolated from the cytoplasmic membranes and characterized by EPR spectroscopy. It has a total molecular mass of 98.7 kDa (subunits of 66.4 and 32.3 kDa), and contains 1 nickel and 12 Fe atoms per heterodimer. The catalytic activities for hydrogen consumption and production were determined to be 174 and 89 mumol H2.min-1.mg-1, respectively. As isolated, under aerobic conditions, this hydrogenase exhibits EPR signals characteristic of the nickel centers in [NiFe] hydrogenases (Ni-A signal at gx,y,z = 2.32, 2.23 and approximately 2.0 and Ni-B signal at gx,y,z = 2.33, 2.16 and approximately 2.0) as well as an intense quasi-isotropic signal centered at g = 2.02 due to the oxidized [3Fe-4S] center. The redox profile under hydrogen atmosphere is remarkably similar to that of other [NiFe] hydrogenases. The signals observed for the oxidized state disappear, first being substituted by the Ni-C type signal (gx,y,z = 2.19, 2.14, approximately 2.01), which upon long incubation under hydrogen yields the split Ni-C signal due to interaction with the reduced [4Fe-4S] centers. PMID- 9367886 TI - The isolation and characterization of the soluble and membrane-bound porcine cytochrome b5 cDNAs. AB - In some male pigs, there is an increased production of the testicular 16 androstene steroids which end up being concentrated in fatty tissue. When the meat is cooked, a disagreeable odor/flavor is produced, a phenomenon known as "boar taint." All boars selected for food production are castrated even though only ca 10% of boars may be "tainted." This has a high economic cost because castrated pigs convert food into meat less efficiently, the meat is fatter, and there is an increased mortality due to the castration procedure. Recent data has implicated an increased level of cytochrome b5 in the testes with the increased synthesis of the 16-androstene steroids. As an initial step in analyzing this process, we used 5' and 3' RACE PCR procedures to isolate, clone and sequence the cDNAs for the membrane-bound and soluble forms of porcine cytochrome b5. PMID- 9367887 TI - Upregulation of the anti-apoptotic protein Bcl-2 may be an early event in neurodegeneration: studies on Parkinson's and incidental Lewy body disease. AB - Apoptosis and oxidative stress have been suggested to be involved in Parkinson's disease (PD). However, whether this is a cause or consequence of neurodegeneration is unknown. Incidental Lewy Body disease (ILBD) appears to be a presymptomatic form of Parkinson's disease where individuals are neurologically normal, but after post-mortem examination pathology similar to Parkinson's disease is present. Thus, ILBD can be used to examine the early stages of the pathological process in PD. We investigated the levels of Bcl-2, an anti apoptotic protein known to decrease cell death induced by several mechanisms, including oxidative stress. Our data show that Bcl-2 is significantly raised in the basal ganglia regions of PD patients as compared to age-matched controls. A similar trend is also found in ILBD. We propose that Bcl-2 increases in some brain regions as an early event and that these brain regions are under a stress for perhaps many years before any symptomatic changes occur. PMID- 9367888 TI - Efficient transfer of genes into senescent cells by adenovirus vectors via highly expressed alpha v beta 5 integrin. AB - Although various methods for transferring genes into mammalian cells have been established, none have been successful with senescent cells. In this report, we present evidence of the efficient transfer of a gene into human senescent fibroblasts using an adenoviral vector. By employing a recombinant adenovirus vector harboring the beta-galactosidase gene (Ad-CAG beta NR), we observed a good correlation between the proportion of beta-galactosidase positive cells and population doubling of the infected cells. In addition, 1.5- to 6.0-fold greater beta-galactosidase activity was observed in senescent fibroblasts (population doubling [PD] = 58) than in young cells (PD = 15). Western blotting analysis revealed that, compared with young fibroblasts, senescent fibroblasts expressed larger amounts of alpha v beta 5 and alpha v beta 3 integrins which were thought to form part of the adenovirus receptor. These results suggest that higher expression of alpha v beta 5 and alpha v beta 3 integrins in senescent cells renders them more sensitive to adenovirus infection than young cells. Thus, adenovirus vectors may prove to be useful in gene therapy strategies directed against senescence-related disorders. PMID- 9367889 TI - Regulation and immunohistochemical analysis of stress protein heme oxygenase-1 in rat kidney with myoglobinuric acute renal failure. AB - Intramuscular injection of hypertonic glycerol solution to rats results in acute renal injury. In this model, the proximal tubules are characteristically damaged. After glycerol injection renal glutathione (GSH) levels drastically decreased. On the other hand, stress protein heme oxygenase-1 (HO-1) was induced. When N-acetyl cysteine was administered to rats before 1 h glycerol injection, renal function was obviously improved. In this condition, the renal GSH content were sustained in the normal levels and HO-1 protein levels were decreased compared with those of glycerol-treated rats. Induction of HO-1 was accompanied by reduced renal GSH content. In addition, to investigate whether the location of HO-1 protein induced by glycerol injection is restricted to injured region or not in the kidney, we determined the localization of HO-1 protein using immunohistochemical staining. HO-1 protein was identified in the epithelia of the distal tubules, Henle's loop and collecting ducts, but not in the injured proximal tubules. PMID- 9367890 TI - CAAT/enhancer binding proteins directly modulate transcription from the peroxisome proliferator-activated receptor gamma 2 promoter. AB - The CCAAT/enhancer binding proteins (C/EBPs) and the peroxisome proliferator activated receptors (PPARs) together regulate adipogenesis. The current work uses co-transfection studies to examine the C/ EBP dependence of PPAR gamma 2 transcription. Both C/ EBP alpha and C/EBP delta expression vectors activated transcription from a PPAR gamma 2 promoter/luciferase expression vector by 5-6 fold in UMR106 cells. The simultaneous transfection of the C/EBP homologous protein (CHOP) (also known as growth arrest DNA damage protein 153 or gadd153) inhibited this C/EBP-dependent activation in a concentration dependent manner. The CHOP protein is known to heterodimerize with other C/EBP proteins to form transcriptionally inactive complexes. Mutation of the two C/EBP DNA recognition elements at -340 bp and -327 bp within the PPAR gamma 2 promoter reduced the inductive effects of both C/EBP alpha and C/EBP delta. These findings demonstrate that proteins within the C/EBP family directly modulate transcription from the PPAR gamma 2 promoter. PMID- 9367891 TI - EGF inhibits expression of WDNM1 and sulfated glycoprotein-2 genes in mammary epithelial cells. AB - We have previously shown that expressions of ferritin heavy chain (FHC), WDNM1, and sulfated glycoprotein-2 (SGP-2) genes are induced at an involution stage of mammary gland. Here we studied the effect of lactogenic hormones and EGF on the expression of involution-induced genes in HC11 mammary epithelial cells. Insulin, dexamethasone, prolactin, and its combinations did not affect expression of the genes. When cells were cultured in growth medium containing EGF, expression of WDNM1 and SGP-2 genes was strongly inhibited in a dose- and time- dependent manner, whereas expression of FHC gene was not influenced by EGF. Results demonstrate that EGF inhibits expression of WDNM1 and SGP-2 genes in mammary epithelial cells. PMID- 9367892 TI - Interaction of the transcription factor YY1 with human poly(ADP-ribosyl) transferase. AB - Poly(ADP-ribosyl) transferase (ADPRT) is a nuclear enzyme that catalyzes the synthesis of ADP-ribose polymers from NAD+ as well as the transfer of these polymers onto acceptor proteins. The function of ADPRT is thought to be related to a number of nuclear processes including DNA repair and transcription. The transcription factor Yin Yang 1 (YY1) is a potent regulator of RNA polymerase II (Pol II)-dependent transcription. In this study Alu-retroposon-associated binding sites for YY1 located in the distal region of the promoter of the human ADPRT gene have been identified suggesting a possible involvement of this protein in the regulation of ADPRT-gene expression. In the presence of the recombinant automodification domain of the ADPRT the formation of specific YY1 complexes, detected in gel-shift experiments, was strongly inhibited, indicating that this domain of the enzyme may interact directly with YY1. In accordance with this result YY1 was specifically precipitated from nuclear extracts by ADPRT immobilized on sepharose. These results suggest a direct ADPRT-YY1 interaction which may be of importance in the regulation of Pol II-dependent transcription. They also indicate that in some human promoters this regulation may be mediated by retroposons of the Alu family. PMID- 9367893 TI - Low density lipoproteins as drug carriers in the therapy of macrophage-associated diseases. AB - Low density lipoproteins (LDL) are internalised by the LDL receptor, which is expressed on the surface of eucaryotic cells. Metabolisation and chemical modification of LDLs lead to a shift in receptor affinity: modified LDLs are internalised through scavenger receptors, which are expressed on cells of the monocyte/ macrophage lineage. Coupling of substances with pharmacological activity, such as azidothymidine, to LDL results in a cell specific uptake of these drugs into macrophages by the scavenger receptor. Thus, drug-LDL derivatives might work as tools for macrophage specific drug targeting. In this context, it is essential to know the drug binding capacity, the optimal derivatization conditions, and the amount of drug molecules covalently bound to the LDL particle. In this study, we compared methods for optimal derivatisation and estimation of coupling efficiency, such as semi-quantitative lipoprotein gel electrophoresis, ultraviolet (UV) spectrophotometry, radiometric quantification, and specific protein hydrolysis. PMID- 9367894 TI - The addition of mitogen-activated protein kinase and p34cdc2 kinase substrate peptides inhibits the flagellar motility of demembranated fowl spermatozoa. AB - The motility of demembranated fowl spermatozoa was vigorous at 30 degrees C, but decreased markedly following the addition of mitogen-activated protein (MAP) kinase or p34cdc2 kinase substrate peptide. Dephosphorylation of approximately 116, 86 and 79-kDa proteins of demembranated spermatozoa was observed after the addition of MAP kinase or p34cdc2 kinase substrate peptide. The activities of MAP kinase and histone H1 kinase of spermatozoa, estimated by measuring the phosphorylation of myelin basic protein and histone H1 as substrates, were 1.22 and 0.29 pmol/min/ mg protein, respectively. Both enzymatic activities of spermatozoa were lower than those of chick brain, but higher than those of chick liver. These results suggest that the phosphorylation of axonemal and/or accessory cytoskeletal proteins mediated by MAP kinase and p34cdc2 kinase may be involved in the regulation of flagellar movement of fowl spermatozoa. PMID- 9367895 TI - Expression of alpha 2 macroglobulin receptor/low density lipoprotein receptor related protein is cell culture density-dependent in human breast cancer cell line BT-20. AB - alpha 2Macroglobulin receptor/low density lipoprotein receptor-related protein (alpha 2MR/LRP) is a multifunctional cell plasma membrane receptor that binds and facilitates the endocytosis of a number of ligands involved in protease regulation and lipoprotein metabolism. In the invasive breast cancer cell line BT 20 we show that the expression of alpha 2MR/LRP can be strongly affected by cell culture density. By comparing measurements of mRNA, total cellular alpha 2MR/LRP antigen, and cell surface alpha 2MR/LRP expression we have demonstrated a marked cell density-dependent regulation of this receptor expression. Increasing the cell density results in a 3.4-fold increase in cell surface alpha 2MR/LRP expression. This corresponds to a marked increase in alpha 2MR/LRP mRNA in Northern blots of total RNA from cells cultured at high density and to consistent increases in alpha 2MR/LRP heavy chain in Western blots of cell lysates from high density cultures. These studies together demonstrate the significant up regulation of alpha 2MR/LRP expression in BT-20 by increased cell density. PMID- 9367896 TI - Regulation of AP-2-synaptotagmin interaction by inositol high polyphosphates. AB - The inositol high-polyphosphate series (IHPS) inhibits neurotransmission through binding to the second C2 domain of synaptotagmins I and II(Syt), synaptic vesicle membrane proteins. We have revealed that several proteins, including alpha adaptins which are specific subunits of clathrin assembly protein, AP2, were eluted from mouse brain by affinity elution chromatography from the C2 domains of Syt II-immobilized Sepharose using 50 microM of InsP6. The interaction between Syt II and AP2 was more markedly inhibited by IHPS than by the same concentration of InsP3. Limited digestion of mouse crude synaptosomal fractions with trypsin revealed different cleavage patterns in the presence and absence of 50 microM InsP6. These results suggest that IHPS-binding to the C2B domain of synaptotagmin alters the state of protein-protein interaction including the synaptotagmin-AP2 interaction, possibly resulting in the inhibition of events involved in the synaptic vesicle trafficking. PMID- 9367897 TI - Control of nitric oxide production by endogenous TNF-alpha in mouse retinal pigmented epithelial and Muller glial cells. AB - Since the induction of nitric oxide synthase (NOS) by lipopolysaccharide (LPS) has been suggested to be partially dependent of the synthesis of tumor necrosis factor alpha (TNF alpha), we have investigated in vitro the production of NO in retinal cells from mice deficient in Lymphotoxin alpha (LT alpha)/TNF alpha. Treatment of retinal Muller glial (RMG) and retinal pigmented epithelial (RPE) cells from both wild-type and knockout mice with LPS and interferon gamma (IFN gamma) induced NO synthesis as determined by nitrite release into the media and was correlated to an increase in NOS-2 mRNA levels, evaluated by RT-PCR. However, the level of nitrite and the accumulation of mRNA was always less in cells from LT alpha/TNF alpha knockout mice than in wild type mice. Simultaneous addition of TNF alpha restored the level of NO synthesis by RMG and RPE cells from LT alpha/TNF alpha knockout mice stimulated with LPS and IFN gamma to wild type levels. Transforming growth factor beta (TGF beta) blocked LPS/IFN gamma-induced NO production is RMG and RPE cells from wild-type and LT alpha/TNF alpha knockout mice. Our results demonstrate that induction of NO synthesis in RMG and RPE cells by LPS and IFN gamma is dependent in part on endogenous TNF alpha while inhibition of NO production by TGF beta does not require a modulation of TNF alpha synthesis. PMID- 9367898 TI - Transcriptional regulation of the mBMP-4 gene through an E-box in the 5'-flanking promoter region involving USF. AB - We analyzed the promoter activity of murine bone morphogenetic protein-4 (mBMP-4) and determined that the 5'-flanking region of exon I plays a critical role for transcription and position -265 to -246 of 5'-flanking region of mBMP-4 gene acts as a cis-element important for the regulation of BMP4 transcription in MC3T3E1 cells. By use of site-directed mutagenesis, we have established that the E-box, CACGTG, located within this short region of promoter, is essential for transcriptional activation of the mBMP-4 gene. Upstream stimulatory factor (USF), a member of the helix-loop-helix (HLH) group of regulatory proteins, was found to bind to this E-box using supershift gel mobility analysis. It is proposed that the HLH transcription regulatory proteins play an important role in mBMP-4 gene transcription in this osteoblastic cell line. PMID- 9367899 TI - Biosynthesis of proteoglycogen: modulation of glycogenin expression in the developing chicken. AB - Glycogenin, the autoglucosyltransferase that primes the biosynthesis of proteoglycogen, is found in the polysaccharide linked proteoglycogen form in mammals and chicken. Glycogenin was released from proteoglycogen and its activity was measured, together with that of glycogen synthase as well as glycogen content, in muscle, liver, and brain during chicken development. The specific activity of glycogenin, expressed per protein, increased with development only in muscle and was higher than the specific activities measured in liver and brain at any time. Concomitant with the rise in activity, an enhanced expression of the protein was observed with Western blot. The specific activity of glycogen synthase increased with development in muscle and liver, while glycogen accumulation was noticeable only in liver. The results indicate that the molar concentration of proteoglycogen is higher in muscle than in liver. The high glycogen content of liver may indicate that the size of the polysaccharide moiety of proteoglycogen is larger in liver than in muscle. This is the first report of developmental modulation of de novo biosynthesis of glycogen at the level of the primer that initiates glucose polymerization. PMID- 9367900 TI - Vicinal thiols are involved in inositol 1,2,3,5,6-pentakisphosphate 5-phosphatase activity from fetal calf thymus. AB - Inositol 1,2,3,5,6-pentakisphosphate (Ins(1,2,3,5,6)P5) 5-phosphatase present in fetal calf thymus has been partially purified. This enzyme was inhibited dose dependently by different thiol modifiers like N-ethylmaleimide (NEM), p chloromercuribenzene sulfonate (PCMBS), diamide, and phenylarsine oxide (PAO). The inhibition by PCMBS and diamide was protected by preincubation with dithiothreitol (DTT) and the phosphatase substrate, Ins(1,2,3,5,6)P5. Diamide, a compound that specifically modifies vicinal thiol groups, also blocked the 5 phosphatase dose-dependently. Specificity of this blockade was proven by using dimercaptopropanol (DMP), a compound known to protect vicinal thiol groups. DMP prevented the enzyme from inhibition by diamide. These data suggest that vicinal thiols are involved in Ins(1,2,3,5,6)P5 5-phosphatase activity. PMID- 9367901 TI - Competitive inhibition of swine kidney copper amine oxidase by drugs: amiloride, clonidine, and gabexate mesylate. AB - Competitive inhibition of swine kidney copper amine oxidase by diuretic, antihypertensive, and anticoagulant drugs, amiloride, clonidine, and gabexate mesylate, respectively, is reported. The affinity of these compounds for swine kidney copper amine oxidase is similar to that observed for inhibitor binding to nitric oxide synthase and trypsin-like serine proteinases. This finding suggests that amiloride, clonidine, and gabexate mesylate should be administrated under careful control, since enzyme cross-inhibition may occur also in vivo. PMID- 9367902 TI - Identification and mutational analysis of rfbG, the gene encoding CDP-D-glucose 4,6-dehydratase, isolated from free living soil bacterium Azotobacter vinelandii. AB - We have identified the rfbG from a non-symbiotic and non-pathogenic soil bacterium, Azotobacter vinelandii. The nucleotide sequence analysis of the rfbG revealed an open reading frame that encodes a peptide of 360 amino acids. This deduced peptide shares 57% homology with the RfbG of Synechocystis and 47% homology with the RfbG of Yersinia pseudotuberculosis. The previously identified short-chain dehydrogenases/reductases family signature sequence is conserved in the sequence of the RfbG of A. vinelandii. Southern blotting analysis of A. vinelandii chromosome by probed with 1.1 kb PstI DNA fragment corresponding to rfbG revealed that it is present as single copy on A. vinelandii chromosome. Disrupting the rfbG present on the chromosome of A. vinelandii, by insertion of kanamycin resistance marker via homologous recombination, resulted in drastic changes in the growth characteristics. The rfbG-negative A. vinelandii grown in liquid medium exhibited agglutination that is characteristic of rfb- mutants of other bacteria, suggesting that we have cloned the functional copy of the rfbG of A. vinelandii. PMID- 9367903 TI - Leukotriene B4 is the functional ligand binding to and activating the cloned chemoattractant receptor, CMKRL1. AB - We recently described a novel chemoattractant receptor, provisionally named CMKRL1, which has turned out to be the first cloned leukotriene (LT) receptor. Present binding assays using tritiated LTB4 and isolated membranes from COS-7 cells, transiently transfected with cDNA encoding this receptor, yielded a linear Scatchard plot showing expression of only a single, high-affinity receptor population with a mean Kd of 2.1 nM and Bmax of 17.0 pmoles/mg protein. Sham transfected cells exhibited no specific binding. LTB4 elicited concentration dependent increases in intracellular calcium measured with Fura-2 in individual CHO cells stably expressing CMKRL1. No response was seen with sham-transfected control cells, or in calcium-free medium which suggests that calcium mainly originates from extracellular sources. The LTB4-induced cellular calcium increment was blocked in the presence of a monoclonal antibody, raised against a synthetic peptide corresponding to the extracellular tail of CMKRL1 and capable of visualizing the receptor by fluorescence immunocytochemistry. Taken together the analyses show that LTB4 is the endogenous ligand for CMKRL1 which is, thus, identical to the LTB4 receptor, designated BLTR according to the NC-IUPHAR nomenclature. PMID- 9367904 TI - Expression and characterization of a trpl homolog from rat. AB - Mammalian homologues of the Drosophila trp/trpl-gene-family code for "Ca(2+) store-operated" channels. Here we describe the cloning and expression of a trp/trpl homologous gene from rat brain. The clone is named Rtrp3 because of its high homology to the recently described Htrp3 (Zhu et al (1996) Cell 85:661-671). Expression of Rtrp3 in the mammalian COS-1 cell line leads to 100% increase of capacitative Ca2+ entry as compared to the controls. This capacitative calcium entry can be completely blocked with La3+ (10 microM). We conclude that Rtrp3, a new member of the growing family of trp/trpl homologues in mammalians, is involved in "Ca(2+)-store-operated" Ca2+ entry into the cell. PMID- 9367905 TI - Macrophage migration inhibitory factor is an essential immunoregulatory cytokine in atopic dermatitis. AB - Macrophage migration inhibitory factor (MIF) is one of the immunoregulatory cytokines involved in T-cell activation and delayed-type hypersensitivity. To elucidate involvement of this cytokine in the pathogenesis of atopic dermatitis (AD), we examined serum MIF concentrations of patients with AD and non-atopic normal healthy individuals. The mean serum MIF concentration of the AD patients (n = 36) was 36.4 +/- 3.7 ng/ml (mean +/- SEM), whereas that of the non-atopic dermatitis patients (n = 17) or healthy individuals (n = 61) were 13.1 +/- 1.8 or 6.5 +/- 0.45 ng/ml, respectively. Accordingly, immunohistochemistry of the inflammatory skin lesion of an AD patient demonstrated that MIF protein was diffusely expressed throughout the whole epidermal layer. After 4-week steroid ointment treatment, the MIF concentration decreased as clinical symptoms improved. The serum level of TNF-alpha was also decreased in parallel with that of MIF. Considering the T-cell dysfunction and disordered cytokine-network reported in AD, it was strongly suggested that MIF was a critical protein for immunoregulation in the pathophysiological mechanism of AD. In this context, MIF may become a useful laboratory parameter to comprehend the clinical course of the disease. PMID- 9367906 TI - Okadaic acid stimulates H ferritin transcription in HeLa cells by increasing the interaction between the p300 CO-activator molecule and the transcription factor Bbf. AB - The transcription of the human H ferritin gene is regulated by a transcription factor, called Bbf, which binds an enhancer element located in the -100/+1 region of the H promoter. To evaluate a possible role of Bbf phosphorylation on the promoter efficiency, we exposed HeLa cells to the phosphatase inhibitor okadaic acid (OA). The okadaic acid treatment increased about 4-fold the transcription driven by the -100/+1 region of the H promoter. However, the DNA binding activity of Bbf was not modified by OA, as assessed by EMSA. Immunoprecipitation experiments demonstrated that the OA-treatment stimulates and/or stabilizes the complex between Bbf and the nuclear protein p300, most probably by inducing the phosphorylation state of the complex. Bbf depends on the p300 molecule to trigger RNA polymerase II and thus transcription of the H ferritin gene. PMID- 9367907 TI - Molecular cloning of a novel human receptor gene with homology to the rat adrenomedullin receptor and high expression in heart and immune system. AB - A novel human gene (named hrhAMR) encoding a seven transmembrane receptor which shares a homology of 73% on the amino acid level with the rat adrenomedullin (AM) receptor has been isolated by a polymerase-chain-reaction (PCR) cloning strategy. Southern- and Northern-blot analysis suggest a single hrhAMR gene, which is highly expressed in heart, skeletal muscle, immune system, adrenal gland and liver, an expression pattern being quite different to that found in rat tissues with the homologue rat probe. Because of its homology with the rat AM receptor, we speculate that potential ligands may be members of the calcitonin-gene-related peptide/amylin/adrenomedullin peptide family. PMID- 9367908 TI - Monitoring of Ca2+ release from intracellular stores in permeabilized rat parotid acinar cells using the fluorescent indicators Mag-fura-2 and calcium green C18. AB - The operation of intracellular Ca2+ stores in saponin-permeabilized rat parotid acinar cells was studied by monitoring the Ca2+ concentration within organelles loaded with the low affinity Ca2+ indicator Mag-fura-2. Inositol 1, 4, 5 trisphosphate (InsP3) caused a decrease in the Mag-fura-2 ratio in a dose dependent manner, and this effect was reversed by a removal of InsP3 or by an addition of the InsP3 receptor antagonist heparin. The changes in Mag-fura-2 ratio indicate the Ca2+ release from InsP3-sensitive Ca2+ stores and Ca2+ re uptake into the stores in permeabilized acinar cells. The decrease in Mag-fura-2 ratio induced by InsP3 was observed at all regions of the acinar cells, suggesting that the InsP3-sensitive Ca2+ stores are located throughout the cells. The InsP3-induced Ca2+ release was also monitored using the membrane-bound Ca2+ indicator Calcium Green C18 which is sensitive to the changes in Ca2+ concentration immediately adjacent to the membrane of intracellular Ca2+ stores. InsP3 caused a large increase in the Calcium Green C18 fluorescence reflecting Ca2+ release from the stores. The Ca2+ pump inhibitor thapsigargin (ThG) itself had little or no effect on the Mag-fura-2 ratio or Calcium Green C18 fluorescence, but combined application of ThG with a low concentration of InsP3 evoked a significant decrease in the Mag-fura-2 ratio. This result supports the hypothesis that the ThG-induced Ca2+ release is due to InsP3-sensitive Ca2+ release which is mediated by the resting levels of InsP3. Further, none of cyclic ADP-ribose, caffeine or ryanodine changed the Mag-fura-2 ratio and Calcium Green C18 fluorescence, leading to the assumption that the ryanodine-sensitive Ca2+ stores are minor in rat parotid acinar cells. PMID- 9367909 TI - Alternative splicing of Pax6 in bovine eye and evolutionary conservation of intron sequences. AB - Pax-6 is essential for eye development and for tissue-specific gene expression within the eye. Splicing of an alternative exon (5a) leads to variant DNA binding specificity in Pax6. Here we show that in the mature bovine eye the relative abundance of the alternative Pax6-5a mRNA varies markedly, particularly between the lens and iris. Additional alternative splicing products were identified which may lead to "domain swapping" or truncation of Pax6 proteins. Comparison of amphibian (Xenopus) and mammalian (bovine) Pax-6 genes revealed highly conserved intronic sequences flanking exon 5a, including potential lariat sites which may have a role in the mechanism of alternative splicing. PMID- 9367910 TI - Inhibition of gene expression from the human c-erbB gene promoter by a retroviral vector expressing anti-gene RNA. AB - Anti-gene is a potent inhibitor of transcriptional promoter activity and subsequent gene expression. This property has been exploited to suppress the expression of a variety of oncogenes for regulating tumor proliferation or viral activities. In this paper, we describe a novel retroviral vector designed to express human c-erbB anti-gene RNA and to reduce the promoter activity in the cells. Mouse fibroblast NIH3T3 cells were stably transfected with an expression construct containing a truncated human c-erbB gene promoter fused to the firefly luciferase reporter gene. Infection into these cells of the c-erbB anti-gene retroviral vector targeted to the 26 bp pyrimidine-rich element in the human c erbB gene promoter resulted in a dose-dependent decrease in the luciferase activity of the cells. Retroviral vector expressing anti-gene RNA may be useful as an alternative program of gene regulation in the cells. PMID- 9367911 TI - A novel class of peptides that induce apoptosis and abrogate tumorigenesis in vivo. AB - In testing the ability of certain synthetic peptides of biological origin to bind to cell surfaces, we unexpectedly found that they could induce apoptosis and inhibit tumorigenesis in rodent and human tumor cell lines. In vitro pre incubation with the peptides at concentrations as low as 10(-12) M inhibited tumorigenesis in nude mice, in a dose-dependent fashion. The inhibition of tumorigenesis was reflected in the rapid induction of apoptosis of tumor cells, pre-incubated with the peptides, and tested under conditions of anchorage independence. Induction of apoptosis was detectable even at concentrations of 10( 12)-10(-13) M (0.1-1.0 pM). Aspecific toxicity of the synthetic peptides was ruled out by the demonstration that single amino acid substitutions (in at least 4 peptides) completely abrogated the pro-apoptotic effect, even at a concentration of 10(-5) M (10 microM). PMID- 9367912 TI - Increase of mouse leptin production by adipose tissue after midpregnancy: gestational profile of serum leptin concentration. AB - The serum concentration of leptin in 10 week old virgin ICR mice assessed by RIA was 1.70 +/- 0.08 ng/ml. The serum leptin concentration in the pregnant mice mated at 10 weeks of age significantly increased from day 11 of pregnancy and reached a peak on day 17 of pregnancy (42.2 +/- 4.8 ng/ml). AFter the delivery, the serum leptin concentration rapidly decreased and reached the level of the virgin mouse on the seventh day in the puerperium. Tissue contents of leptin in the placenta, the decidua, the uterus, and the adipose tissue were between 40 to 130 ng/g wet tissue. However, leptin mRNA was expressed only in the adipose tissue and the level of leptin mRNA on days 13 and 17 of pregnancy increased 3- to 5-fold compared with that of virgin mouse. Tissue content of leptin in the adipose tissue significantly increased from day 17 of pregnancy compared with that of the virgin mouse. The m-leptin secretion from the adipose tissue also significantly increased in vitro. These results suggest that leptin, which was secreted by adipose tissue, may play important roles in mouse reproduction after midpregnancy. PMID- 9367913 TI - The proteoglycan metabolism of mature bovine articular cartilage explants superimposed to continuously applied cyclic mechanical loading. AB - This study describes the effect of load magnitude, frequency and duration on proteoglycan (PG) biosynthesis and loss in mature bovine articular cartilage explants. Cultured full thickness cartilage discs were subjected to a continuously applied, uniaxial compressive cyclic load. The loads were applied using a sinusoidal waveform of 0.001, 0.01, 0.1 or 0.5 Hz-frequency and a peak stress of 0.1, 1.0, 2.5, or 5.0 MPa for a period of 1, 3 or 6 days. Increasing the load magnitude, as well as the duration of loading, reduced the PG biosynthesis. Reducing the load frequency abolished the inhibitory effect of a given load magnitude on PG biosynthesis, even though explants were more compressed. Increasing the load magnitude stimulated the release of newly synthesized PGs from explants, whereas an elevated duration of loading significantly decreased the release of endogenous PGs. Explants loaded for 1 or 3 days were viable as determined biochemically, whereas 6 days of loading resulted in a slightly diminished viability of explants. This study demonstrates that the duration and intensity of loading influences the inhibition of PG biosynthesis, while PG loss is only modulated by the magnitude and duration of loading. PMID- 9367915 TI - The trimerization domain of human heat shock factor 2 is able to interact with nucleoporin p62. AB - Heat shock factor 2 (HSF2) acquires DNA binding activity during hemin-induced differentiation of human K562 erythroleukemia cells. To investigate the mechanisms responsible for the regulation of HSF2 activity, we searched for proteins that can associate with HSF2 by the yeast two-hybrid system. Nucleoporin p62, a major component of the nuclear pore complex, was cloned from cDNA libraries of K562 cells. We demonstrated physical interaction between HSF2 and p62 both by a glutathione S-transferase (GST) pull-down assay in vitro and by a two-hybrid assay in K562 cells. HSF1 is also able to interact with p62 on a GST pull-down assay, but not on a mammalian two-hybrid system. Furthermore, it was shown that this interaction occurred between the trimerization domain of HSF2 and the C-terminal alpha-helical coiled-coil domain of p62. These data suggest the possibility that p62 is involved in the activation or regulation of HSF2. PMID- 9367914 TI - Regulation of the third member of the uncoupling protein family, UCP3, by cold and thyroid hormone. AB - Uncoupling protein (UCP1) is a transmembrane proton transporter present in the mitochondria of brown adipose tissue (BAT), a specialized tissue which functions in temperature homeostasis and energy balance (Nicholls, D. G., and Locke, R. M. (1984) Physiol. Rev. 64, 2-40; Lowell, D. D., and Flier, J. S. (1997) Annu. Rev. Med.). UCP1 mediates the thermogenesis that is characteristic of BAT by uncoupling mitochondrial oxidation of substrates from ATP synthesis. Recently, two proteins related to UCP1 have been identified and designated UCP2 (Fleury, C., et al. (1997) Nature Genetics 15, 269-272) or UCP homolog (UCPH) (Gimeno, R. E., et al. (1997) Diabetes 46, 900-906) and UCP3 (Boss, O., et al. (1997) FEBS Lett. 408, 39-42; Vidal-Puig, A., et al. (1997) Biochem. Biophys. Res. Commun. 235, 79-82). We investigated the regulation in rats of UCP3, which is expressed primarily in skeletal muscle and BAT. Expression of rat UCP3 mRNA in BAT was upregulated by in vivo treatment with triiodothyronine (T3) and by exposure to cold, suggesting that UCP3 is active in thermogenesis and energy expenditure. In skeletal muscle, UCP3 mRNA was also upregulated by T3 but, surprisingly, not by cold exposure. A hypothesis is proposed to account for this differential regulation. PMID- 9367918 TI - Introduction: Emerging vaccine strategies AB - No abstractCopyright 1997 Academic Press Limited Copyright 1997Academic Press Limited PMID- 9367916 TI - Cherimolin-1, new selective inhibitor of the first energy-coupling site of the NADH: ubiquinone oxidoreductase (complex I). AB - The mechanism linking electron transport to proton translocation in the NADH:ubiquinone oxidoreductase (complex I of the mitochondrial respiratory chain) is still unclear. Inhibitors acting at different sites of the enzyme are powerful tools to clarify this mechanism. Up to now, a unique inhibitor, the Annonaceous acetogenin rolliniastatin-2, selectively blocks the most internal proton translocation site. This study introduces cherimolin-1, a new acetogenin that inhibits the complex I with this special mode of action, which is more easily available from the plant material. Moreover, the mode of action of this scarce type of complex I inhibitor is further characterized. PMID- 9367917 TI - Cloning of novel trinucleotide-repeat (CAG) containing genes in mouse brain. AB - CAG trinucleotide repeat (CTR) sequence often appears in mammalian genome including transcription-regulatory protein and homeobox genes. Its expansion is associated with six genetic disorders in human. To identify novel CTR-containing genes expressed in mouse brain, a brain cDNA library was screened using an oligonucleotide, (CTG)10. Eight clones were novel mouse genes and they were sequenced on both strands. The size of the cloned DNA ranged from 0.5 to 2.1 kb. The number of the CAG repeats in the clones ranged from 6 to 25. The inserts of the clones were analyzed for open reading frames and the peptide sequences were used for a GenBank homology search. Of the clones, one (CAG-6) shared 13 consecutive identical amino acid residues with the OB-cadherin gene, a member of cadherin family. CAG-14 showed high homology (657 nucleotides identity in 1022 nucleotides; 64%) with the 3'-untranslated region of rat leukocyte common antigen related (LAR) tyrosine phosphatase receptor. All the 8 clones were originated from mouse DNA as judged by Southern blot analysis of mouse genomic DNA. The expression of the clones in mouse brain was addressed by RT-PCR and 4 clones showed specific expression. PMID- 9367938 TI - Spirometrically controlled high resolution computed tomography - quantitative assessment of density distribution in patients with diffuse fibrosing alveolitis. AB - STUDY OBJECTIVE: Lung density assessed by high resolution computed tomography (HRCT) is sufficiently sensitive for the diagnosis of interstitial lung disease, but may be hampered by uneven disease distribution. We determined the mean and subpleural density values in patients with diffuse fibrosing alveolitis (FA) and evaluated the diagnostic accuracy of both parameters, expressed as post-test odds ratios. MATERIALS AND METHODS: Pulmonary HRCT was performed on 21 FA patients and compared to scans of 27 healthy volunteers. The HRCT procedure was standardized by taking 3 scans at the carina +/- 5 cm, and by defining inspiration levels at 50% vital capacity. Mean lung density (MLD) and subpleural lung density (SLD) were calculated for all participants. RESULTS: MLD and SLD values for healthy subjects were significantly higher compared with the patient group. Odds ratios were 7.8:1 and 3.9:1 for SLD and MLD, respectively, demonstrating a superior discrimination power of SLD in the diagnosis of FA. CONCLUSION: Diagnostic accuracy of quantitative HRCT measurements in FA was improved by the separate evaluation of subpleural lung density, which is a better indicator of the presence or absence of lung fibrosis than is mean lung density. PMID- 9367939 TI - Clinical assessment of periodontal conditions in patients treated with nifedipine. AB - Calcium antagonists are widely used in treating acute and chronic coronary insufficiency disorders. A major side effect of long-term treatment is gingival hyperplasia. In the present study, 70 patients taking nifedipine for at least six months and 70 controls similar in age, gender, approximal hygiene and systemic disease with at least 6 anterior teeth in upper and lower arches were examined. Their periodontal conditions were determined by modified Sulcus-Bleeding-Index (mSBI), modified Approximal-Plaque-Index (mAPI), Community Periodontal Index of Treatment Needs (CPITN), a hyperplasia index quantifying the extent of gingival overgrowth, probing depths, clinical attachment loss and the modified Phenytoin Gingival-Inflammation-Index (mPGI). A mild to moderate gingival hyperplasia was diagnosed in 21 of 70 patients resulting in a prevalence of 30% compared to 8.5% in controls. The hyperplastic changes were situated mainly in the anterior region of the dentition. Significant differences between both groups could be found comparing the severity of the gingival hyperplasia, the CPITN, mSBI, probing depths and the part of mPGI evaluating colour and turgor of the gingiva (p < 0.05). The severity of gingival overgrowth was strongly correlated with the inflammatory gingival changes, probing depths, the periodontal treatment need and the approximal hygiene of the patients. No statistically significant correlation could be found between the severity of gingival hyperplasia and the age and gender of the patient, or the dose or duration of nifedipine therapy. Gingival changes seemed to be more pronounced in patients with cardiovascular disorders than in patients under hemodialysis. The high incidence of gingival hyperplasia in patients receiving nifedipine on a long-term basis emphasises the role of the dentist and general practitioner in the early detection and prophylaxis of gingival changes and requires a thorough information to the patient concerning periodontal side effects. PMID- 9367940 TI - The relationship between the frequency of the appearance of IgG against Helicobacter pylori and the main blood groups among patients with ulcer sickness and stomach cancer. AB - Among the 763 patients with ulcers and stomach cancer, including the control group of 586 blood donors, the search for a relationship between the spread of infection and the main blood groups was defined by the appearance of IgG against H. pylori in blood plasma (the ELISA test). The statistical analysis, however, did not prove that the frequency of the appearance of specific antibodies against H. pylori was statistically important in relation to the ABO blood groups. PMID- 9367941 TI - Source density analysis of functional topographical EEG: monitoring of cognitive drug action. AB - Electrical changes of the brain induced by mental work in the presence or absence of a drug formulation containing dimethylaminoethanolorotrate (DMAE), vitamins and minerals were analysed. Sixty elderly volunteers (30 females and 30 males; aged 40 - 65) who lacked concentration and efficiency during mental exercise according to their own opinions participated in a double-blind, placebo controlled study. The EEG recordings were carried out before and after 12 weeks medication and were analysed according to the electrical charges at the scalp surface (Laplacian estimate) followed by Fast Fourier Transformation to obtain quantitative data. Whereas no change of electrical charge could be observed after 12 weeks of treatment in the placebo group, the verum group taking 1 capsule per day of an established drug containing a biogenic amine-vitamin combination revealed decreases in theta power during rest and increases in absolute theta power induced by mental demand within the area known to change its electrical activity during mental exercise. In the light of the current hypothesis that high theta resting power and low increases at frontotemporal brain areas during mental work indicate mental impairment, treatment with the drug under investigation was seen to successfully reverse these changes. This drug effect was localized in the frontotemporal cortex in a statistically significant manner during both the memory and the symbol recognition tests. The observed effect is fully consistent with a previous study using Fourier transformed data from conventional EEG voltage recordings. It can be concluded that an analysis of EEG data by means of the charge mode provides an excellent tool to quantify drug effects especially in cognitive research. A second perspective arises from the fact that it should be possible to recognize mental impairments at a very early stage by using this method, thus providing the possibility of an early treatment. PMID- 9367942 TI - Effect of organic nitrates on ex vivo platelet aggregation and fibrinolysis in man. AB - Previous in vitro studies have suggested that nitric oxide-releasing agents can increase the fibrinolytic capacity while platelet aggregability is decreased. We have therefore directly compared the influence of organic nitrates on ex vivo platelet aggregation and the fibrinolytic system in 16 healthy volunteers. Each subject received glyceryl trinitrate (GTN, 2 x 32 mg patches), isosorbide dinitrate (ISDN, 120 mg p.o.), isosorbide-5-mononitrate (ISMN, 50 mg p.o.), and placebo in a randomized double-blind manner. Ex vivo platelet aggregation, activities and concentrations of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) were measured before, 90 and 150 minutes after drug intake. GTN, ISDN, and ISMN were equipotent in respect to their hemodynamic responses. Platelet aggregation induced with a low (1 microM) but not with a high (4 microM) agonist concentration (adenosine diphosphate, ADP) was reduced after GTN and ISDN. ISMN had no influence on aggregation. An increase of t-PA activity was significantly reduced after GTN and ISDN (p<0.05), whereas t PA concentrations were not affected by the nitrates. A decrease of PAI-1 activity after ISMN and placebo was not apparent after GTN and ISDN. In the case of GTN, the decrease of PAI-1 concentration was delayed. In conclusion, GTN and ISDN did not increase the fibrinolytic capacity but decreased the reversible phase of ADP induced platelet aggregation, while ISMN had neither an effect on the fibrinolytic system nor on platelet aggregation. PMID- 9367943 TI - Oligosymptomatic neurosyphilis with false negative CSF-VDRL in HIV-infected individuals? AB - The true prevalence of neurosyphilis in HIV-infection is unknown, since a sufficiently sensitive and specific test is lacking. In a prospective study we found reactive serum TPHA and FTA-ABS IgG tests in 95 (31%) of 307 HIV-infected patients. Three of 11 patients with latent syphilis revealed reactive CSF-VDRL tests, six others only demonstrated CSF abnormalities. Resolution of CSF abnormalities during a six month follow up after high dose antibiotic therapy led to the diagnosis of oligosymptomatic or asymptomatic neurosyphilis in all nine patients. Thus, the specificity of the CSF-VDRL was 100%, but the sensitivity was only 33%. The overall prevalence of neurosyphilis was 2.9%, increasing to 9.5% in patients with a reactive serum TPHA. Our study emphasizes the importance of antibiotic therapy for presumptive neurosyphilis in HIV-infected patients with latent syphilis and CSF abnormalities but nonreactive CSF-VDRL tests, even if they are neurologically asymptomatic or present with complaints inconclusive of neurosyphilis. PMID- 9367944 TI - Evaluation of ERCP- and endoscopic sphincterotomy-induced pancreatic damage: a prospective study on the time course and the significance of serum levels of pancreatic secretory enzymes. AB - In the present study the time courses of serum lipase, serum amylase and serum elastase 1 after ERCP/ES as indicators for pancreatic damage were prospectively analysed in 46 cases. The elevations of pancreatic enzymes after ERCP/ES scattered in a wide range and elevations occured which were greater than one hundred times the upper limit of normal. A moderate increment was seen as early as 5 minutes after intubation of the papilla. Elevations above the upper limit of normal were still seen at 24 hours after the procedure. The maxima occurred about 6 hours after the procedure. Lipase was the most sensitive among the parameters tested, nearly 50% of the cases with previously normal values revealed elevated lipase after the procedure. For daily clinical routine a single lipase measurement at 2 hours after the beginning of the ERCP/ES provides valuable information for planning further surveillance. Younger age and high calcium levels seem to be risk factors for ERCP/ES-induced pancreatic damage. The time course of serum lipase seems to be a more reliable criterion for ERCP/ES-induced pancreatic damage than the poorly defined complication of post-ERCP pancreatitis . The high incidence of a measurable pancreatic injury after ERCP/ES provides a sensitive tool for the testing of drugs claimed to be protective for the pancreas and for evaluating new ERCP/ES techniques. Measurement of the serum lipase before, 8 and 24 hours after the procedure, and a detailed description of degree and duration of pain, are necessary for such studies. PMID- 9367945 TI - The impact of microbiological diagnostics on the antimicrobial treatment of hospitalised patients with infectious disease. AB - We evaluated a total of 160 treatment protocols from the unit of internal medicine (n = 100) and the intensive care unit (n = 60) of the Bonn University Hospital to detect the influence of microbiological diagnostics on the individual antimicrobial treatment. Ninety-six of hundred patients in regular care were set on empirical antibiotic treatment within 24 to 48 hours after onset of symptoms. In 91% of the cases cure or substantial improvement was achieved via the initial therapy. Microbiological survey revealed multi-resistant pathogens which could be handled using a specific treatment in six of the remaining patients. In contrast, sixty patients in intensive care proved to benefit significantly from microbiological diagnostics. In one quarter of the cases microbiological findings supported the decision on a reasonable escalated therapy, and in another quarter the initial therapeutic schedule could be confirmed. At any rate, about one third of the infections remained bacteriologically inexplicable in spite of excessive microbiological research. Thus, the results of this retrospective evaluation confirm the common practice of an initial antibiotic treatment without bacteriological investigation in less severe and in severe infections. Microbiological screening may help to decide on effective routine antibiosis in patients with less severe infections. We recommend comprehensive individual microbiological diagnostics in patients with severe nosocomial pneumonia or sepsis and in patients at high risk for Candida superinfections. Due to steadily increasing economic pressure, it is necessary to reflect on the expenditure for microbiological diagnostics. The cost-effectiveness-ratio may be optimised mainly in patients with less severe infections and in regular care. The number of microbiological surveys and expenditures in ICU patients appeared adequate as compared to the individual benefit. PMID- 9367946 TI - Colliding beam fusion reactor AB - Recent results with Tokamak experiments provide insights into the problem of magnetic confinement. They demonstrate how to avoid anomalous transport and thus solve the major problems of Tokamak reactors: size, the production of 14 megaelectron volt neutrons, and maintenance. An alternate confinement system, the field-reversed configuration, confines beams of protons and boron-11. For the proton-boron-11 fusion reaction, the fusion products are all charged particles for which direct conversion is feasible and neutron flux is negligible. PMID- 9367947 TI - Impact of lower atmospheric carbon dioxide on tropical mountain ecosystems AB - Carbon-isotope values of bulk organic matter from high-altitude lakes on Mount Kenya and Mount Elgon, East Africa, were 10 to 14 per mil higher during glacial times than they are today. Compound-specific isotope analyses of leaf waxes and algal biomarkers show that organisms possessing CO2-concentrating mechanisms, including C4 grasses and freshwater algae, were primarily responsible for this large increase. Carbon limitation due to lower ambient CO2 partial pressures had a significant impact on the distribution of forest on the tropical mountains, in addition to climate. Hence, tree line elevation should not be used to infer palaeotemperatures. PMID- 9367948 TI - Evolution of magnetic and superconducting fluctuations with doping of high-Tc superconductors AB - Electronic Raman scattering from high- and low-energy excitations was studied as a function of temperature, extent of hole doping, and energy of the incident photons in Bi2Sr2CaCu2O8+/-delta superconductors. For underdoped superconductors, short-range antiferromagnetic (AF) correlations were found to persist with hole doping, and doped single holes were found to be incoherent in the AF environment. Above the superconducting (SC) transition temperature Tc, the system exhibited a sharp Raman resonance of B1g symmetry and energy of 75 millielectron-volts and a pseudogap for electron-hole excitations below 75 millielectron-volts, a manifestation of a partially coherent state forming from doped incoherent quasi particles. The occupancy of the coherent state increases with cooling until phase ordering at Tc produces a global SC state. PMID- 9367949 TI - Nearly singular magnetic fluctuations in the normal state of a high-Tc cuprate superconductor AB - Polarized and unpolarized neutron scattering was used to measure the wave vector- and frequency-dependent magnetic fluctuations in the normal state (from the superconducting transition temperature, Tc = 35 kelvin, up to 350 kelvin) of single crystals of La1.86Sr0.14CuO4. The peaks that dominate the fluctuations have amplitudes that decrease as T-2 and widths that increase in proportion to the thermal energy, kBT (where kB is Boltzmann's constant), and energy transfer added in quadrature. The nearly singular fluctuations are consistent with a nearby quantum critical point. PMID- 9367950 TI - Direct measurement of the current-phase relation of a superfluid 3He-B weak link AB - Direct measurements of the current-phase relation, I versus Deltaphi, for a weak link coupling two reservoirs of B-phase superfluid helium-3 (3He-B) were made over a wide range of temperatures. The weak link consists of a square array of 100-nanometer-diameter apertures. For temperatures T such that T/Tc >/= 0.6 (where Tc is the superfluid transition temperature), I approximately sin(Deltaphi). At lower temperatures, I(Deltaphi) approaches a straight line. Several remarkable phenomena heretofore inaccessible to superconducting Josephson junctions, including direct observation of quantum oscillations and continuous knowledge of Deltaphi, were also observed. PMID- 9367951 TI - A tribosphenic mammal from the Mesozoic of Australia. AB - A small, well-preserved dentary of a tribosphenic mammal with the most posterior premolar and all three molars in place has been found in Aptian (Early Cretaceous) rocks of southeastern Australia. In most respects, dental and mandibular anatomy of the specimen is similar to that of primitive placental mammals. With the possible exception of a single tooth reported as Eocene in age, terrestrial placentals are otherwise unknown in Australia until the Pliocene. This possible Australian placental is similar in age to Prokennalestes from the late Aptian/early Albian Khoboor Beds of Mongolia, the oldest currently accepted member of the infraclass Placentalia. PMID- 9367952 TI - Contribution of stream channel erosion to sediment yield from an urbanizing watershed AB - Stream channel erosion has long been suspected as the major contributor to long term sediment yield from urbanizing watersheds. For San Diego Creek in southern California, measurements from 1983 to 1993 showed that stream channel erosion furnished 10(5) megagrams per year of sediment, or about two-thirds of the total sediment yield. Thus, because channel erosion can be a major source of sediment yield from urbanizing areas, channel stabilization should be a priority in managing sediment yield. PMID- 9367953 TI - Adatom pairing structures for Ge on si(100): the initial stage of island formation AB - With the use of scanning tunneling microscopy, it is shown that germanium atoms adsorbed on the (100) surface of silicon near room temperature form chainlike structures that are tilted from the substrate dimer bond direction and that consist of two-atom units arranged in adjoining substrate troughs. These units are distinctly different from surface dimers. They may provide the link missing in our understanding of the elementary processes in epitaxial film growth: the step between monomer adsorption and the initial formation of two-dimensional growth islands. PMID- 9367955 TI - Insolation cycles as a major control of equatorial indian ocean primary production AB - Analysis of a continuous sedimentary record taken in the Maldives indicates that strong primary production fluctuations (70 to 390 grams of carbon per square meter per year) have occurred in the equatorial Indian Ocean during the past 910,000 years. The record of primary production is coherent and in phase with the February equatorial insolation, whereas it shows diverse phase behavior with delta18O, depending on the orbital frequency (eccentricity, obliquity, or precession) examined. These observations imply a direct control of productivity in the equatorial oceanic system by insolation. In the equatorial Indian Ocean, productivity is driven by the wind intensity of westerlies, which is related to the Southern Oscillation; therefore, it is suggested that a precession forcing on the Southern Oscillation is responsible for the observed paleoproductivity dynamics. PMID- 9367954 TI - Vigorous HIV-1-specific CD4+ T cell responses associated with control of viremia. AB - Virus-specific CD4+ T helper lymphocytes are critical to the maintenance of effective immunity in a number of chronic viral infections, but are characteristically undetectable in chronic human immunodeficiency virus-type 1 (HIV-1) infection. In individuals who control viremia in the absence of antiviral therapy, polyclonal, persistent, and vigorous HIV-1-specific CD4+ T cell proliferative responses were present, resulting in the elaboration of interferon gamma and antiviral beta chemokines. In persons with chronic infection, HIV-1 specific proliferative responses to p24 were inversely related to viral load. Strong HIV-1-specific proliferative responses were also detected following treatment of acutely infected persons with potent antiviral therapy. The HIV-1 specific helper cells are likely to be important in immunotherapeutic interventions and vaccine development. PMID- 9367956 TI - Connectivity and management of caribbean coral reefs AB - Surface current patterns were used to map dispersal routes of pelagic larvae from 18 coral reef sites in the Caribbean. The sites varied, both as sources and recipients of larvae, by an order of magnitude. It is likely that sites supplied copiously from "upstream" reef areas will be more resilient to recruitment overfishing, less susceptible to species loss, and less reliant on local management than places with little upstream reef. The mapping of connectivity patterns will enable the identification of beneficial management partnerships among nations and the design of networks of interdependent reserves. PMID- 9367957 TI - Crystal structure of methyl-coenzyme M reductase: the key enzyme of biological methane formation. AB - Methyl-coenzyme M reductase (MCR), the enzyme responsible for the microbial formation of methane, is a 300-kilodalton protein organized as a hexamer in an alpha2beta2gamma2 arrangement. The crystal structure of the enzyme from Methanobacterium thermoautotrophicum, determined at 1.45 angstrom resolution for the inactive enzyme state MCRox1-silent, reveals that two molecules of the nickel porphinoid coenzyme F430 are embedded between the subunits alpha, alpha', beta, and gamma and alpha', alpha, beta', and gamma', forming two identical active sites. Each site is accessible for the substrate methyl-coenzyme M through a narrow channel locked after binding of the second substrate coenzyme B. Together with a second structurally characterized enzyme state (MCRsilent) containing the heterodisulfide of coenzymes M and B, a reaction mechanism is proposed that uses a radical intermediate and a nickel organic compound. PMID- 9367958 TI - Targeting of HIV- and SIV-infected cells by CD4-chemokine receptor pseudotypes. AB - Retroviral vectors containing CD4 and an appropriate chemokine receptor were evaluated for the ability to transduce cells infected with human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV). These CD4-chemokine receptor pseudotypes were able to target HIV- and SIV-infected cell lines and monocyte derived macrophages in a manner that corresponded to the specificity of the viral envelope glycoprotein for its CD4-chemokine receptor complex. This approach could offer a way to deliver antiviral genes directly to HIV-infected cells in vivo and could provide an additional treatment strategy in conjunction with existing antiviral therapies. PMID- 9367959 TI - Inhibition of invasion of epithelial cells by Tiam1-Rac signaling. AB - Tiam1 encodes an exchange factor for the Rho-like guanosine triphosphatase Rac. Both Tiam1 and activated RacV12 promote invasiveness of T lymphoma cells. In epithelial Madin-Darby canine kidney (MDCK) cells, Tiam1 localized to adherens junctions. Ectopic expression of Tiam1 or RacV12 inhibited hepatocyte growth factor-induced scattering by increasing E-cadherin-mediated cell-cell adhesion accompanied by actin polymerization at cell-cell contacts. In Ras-transformed MDCK cells, expression of Tiam1 or RacV12 restored E-cadherin-mediated adhesion, resulting in phenotypic reversion and loss of invasiveness. These data suggest an invasion-suppressor role for Tiam1 and Rac in epithelial cells. PMID- 9367960 TI - Sec-independent protein translocation by the maize Hcf106 protein. AB - The bacterial Sec and signal recognition particle (ffh-dependent) protein translocation mechanisms are conserved between prokaryotes and higher plant chloroplasts. A third translocation mechanism in chloroplasts [the proton concentration difference (DeltapH) pathway] was previously thought to be unique. The hcf106 mutation of maize disrupts the localization of proteins transported through this DeltapH pathway in isolated chloroplasts. The Hcf106 gene encodes a receptor-like thylakoid membrane protein, which shows homology to open reading frames from all completely sequenced bacterial genomes, which suggests that the DeltapH pathway has been conserved since the endosymbiotic origin of chloroplasts. Thus, the third protein translocation pathway, of which HCF106 is a component, is found in both bacteria and plants. PMID- 9367961 TI - CD4-independent binding of SIV gp120 to rhesus CCR5. AB - CCR5 and CD4 are coreceptors for immunodeficiency virus entry into target cells. The gp120 envelope glycoprotein from human immunodeficiency virus strain HIV 1(YU2) bound human CCR5 (CCR5hu) or rhesus macaque CCR5 (CCR5rh) only in the presence of CD4. The gp120 from simian immunodeficiency virus strain SIVmac239 bound CCR5rh without CD4, but CCR5hu remained CD4-dependent. The CD4-independent binding of SIVmac239 gp120 depended on a single amino acid, Asp13, in the CCR5rh amino-terminus. Thus, CCR5-binding moieties on the immunodeficiency virus envelope glycoprotein can be generated by interaction with CD4 or by direct interaction with the CCR5 amino-terminus. These results may have implications for the evolution of receptor use among lentiviruses as well as utility in the development of effective intervention. PMID- 9367962 TI - Vasculitis and the nervous system. Historical perspective and overview. AB - This article is an introduction to the historical background, clinical and laboratory diagnosis, pathogenesis, and treatment of vasculitis involving the peripheral and central nervous system. It also provides a background for the articles that follow. PMID- 9367963 TI - Diagnostic approach to central and peripheral nervous system vasculitis. AB - The diagnosis of vasculitis is first and foremost a clinical one. Correct diagnosis requires a high index of suspicion coupled with knowledge of the manifestations of other disorders that may masquerade as vasculitis. Treatment of vasculitis requires prolonged use of drugs with the potential for serious side effects. Whereas the prompt initiation of definitive treatment is a very high priority, there is also substantial risk of inappropriately treating self-limited and more benign disorders mimicking vasculitis. This has been a particular problem with primary angiitis of the central nervous system. Laboratory studies, particularly tissue biopsy, provide a crucial adjunct to clinical diagnosis. PMID- 9367964 TI - Radiographic features of central nervous system vasculitis. AB - Central nervous system (CNS) vasculitis refers to primary and secondary disorders of the CNS vasculature. Most authorities agree that CNS vasculitis is a potentially serious disorder; therefore, prompt diagnosis and initiation of therapy are high priorities in treatment. Remarkable progress has been made in the diagnosis, evaluation, and treatment of this disorder. This article examines many aspects of the radiographic evaluation of CNS vasculitis. PMID- 9367965 TI - Classification and histopathologic spectrum of central nervous system vasculitis. AB - There are many different and diverse causes of central nervous system (CNS) vasculitis, and many nonvasculitic disorders that often mimic CNS vasculitis. CNS vasculitis is usually suspected clinically with compatible or suggestive angiographic findings, but a definitive diagnosis is not possible without biopsy confirmation, especially with CNS vasculitis mimickers. Primary CNS vasculitis, although relatively uncommon, is most important because of its overall unfavorable prognosis. Secondary CNS vasculitis occurs in association with a long list of systemic vasculitic and nonvasculitic disorders with variable brain biopsy findings. Because of the focal and segmental distribution of CNS vasculitis, a positive biopsy is diagnostic for the disease demonstrated, but a single isolated negative biopsy does not necessarily exclude primary or secondary CNS vasculitis. PMID- 9367966 TI - Granulomatous angiitis of the nervous system. AB - Granulomatous angiitis of the nervous system (GANS) refers to distinctive clinicopathologic disorders with the essential feature of granulomatous inflammation of cerebral and spinal vessels, accompanied by multinucleate giant cells and epithelioid cells. This article reviews and examines the clinical, laboratory, and neuropathologic findings of patients with granulomatous angiitis. PMID- 9367967 TI - Necrotizing peripheral nerve vasculitis. AB - Necrotizing vasculitis of the type in polyarteritis nodosa is a treatable cause of neuropathy. The diagnosis must be confirmed histologically by demonstration of characteristic arterial lesions in nerve and muscle biopsy specimens. Ischemic neuropathy which results from occlusion of nerve arteries in polyarteritis nodosa also occurs as a consequence of inflammatory arterial lesions in other connective tissue disorders, in some infectious neuropathies and in patients with malignant lymphomas. Patients with vasculitic neuropathy may also present with isolated peripheral neuropathy. PMID- 9367968 TI - Paraneoplastic vasculitis of the peripheral nervous system. AB - Paraneoplastic vasculitic neuropathy (PVN) is a rare paraneoplastic syndrome characterized by non-systemic subacute vasculitic neuropathy. The two cancers most commonly associated with PVN are small cell lung cancer (SCLC) and lymphomas. Neuropathy varies from mononeurotherapy multiplex to symmetrical polyneuropathy. Two helpful laboratory abnormalities are a high erythrocyte sedimentation rate (ESR) and high cerebro spinal fluid (CSF) protein content. Axonal neuropathy is the characteristic finding in electrophysiological studies. Nerve biopsy is crucial to document microvasculitis. Recognition of this entity is important because of its potential treatability. Unlike other paraneoplastic syndromes, anti-cancer chemotherapy and immunotherapy for vasculitis are both effective in this disorder. PMID- 9367970 TI - Wegener's granulomatosis and ANCA syndromes. AB - The nervous system is involved in approximately 25% of patients with classical Wegener's granulomatosis. The spectrum of this disease has been broadened with the discovery of the anti-neutrophil cytoplasmic antibodies, which are found in diseases sharing many clinical features. The ANCA testing may indicate a common mode of pathogenesis. The definitive diagnostic marker is histological, and that forms the best guide to specific therapy. PMID- 9367969 TI - Polyarteritis nodosa, microscopic polyangiitis, and Churg-Strauss syndrome: clinical aspects, neurologic manifestations, and treatment. AB - Polyarteritis nodosa (PAN), microscopic polyangiitis (MPA), and Churg-Strauss syndrome (CSS) all have neurologic symptoms and share characteristics and outcomes. Clinical aspects, neurologic manifestations, and treatment of these three diseases are examined in this article. PMID- 9367971 TI - Giant cell (temporal) arteritis. AB - Headache is the most frequent symptom for which a patient with giant cell arteritis (GCA) presents to a neurologist. Amaurosis fugax and ischemic optic neuropathy are well recognized complications. Less commonly recognized neurologic complications include transient ischemic attacks, cerebral infarctions, acute confusional states, multi-infarct dementia, ischemic cervical myelopathy, and ischemic mononeuropathies. Because patients with GCA generally respond well to corticosteroid therapy, prompt diagnosis can minimize neurologic damage. PMID- 9367972 TI - Vasculitis owing to infection. AB - Infections are a recognized cause of secondary vasculitis. A variety of pathogens have a propensity to involve blood vessels. Vasculitis, non-vasculitic vasculopathy, and mycotic aneurysms lead to infarction and hemorrhage of nervous system tissue. Treatment of infection-related vasculitis should include appropriate antimicrobial therapy directed against the offending pathogen, and appropriate management of cerebrovascular complications. PMID- 9367973 TI - Retroviral-associated vasculitis of the nervous system. AB - Vasculitis may involve the central and peripheral nervous system in HIV-infected patients. Central nervous system vasculitis is rare with HIV infection and most are owing to opportunistic infections including varicella, CMV, fungal, tuberculosis, and syphilis. Vasculitis of the peripheral nerve may cause mononeuritis multiplex or polyneuropathy, sometimes as the first symptom of HIV or after AIDS has developed. Symptoms may be limited to the peripheral nerve. The etiology may be infection of endothelial cells, hepatitis B or HIV-induced immune complexes, or dysregulation of cytokines and adhesion molecules. Treatment with steroids alone is often effective; IVIg and cytotoxic agents have also been used. It is uncertain whether vasculitis of the nervous system is ever due to other retroviruses (HIV-2, HTLV-1, and HTLV-2). PMID- 9367974 TI - Vasculitis owing to substance abuse. AB - The term drug dependence refers to psychic dependence (addiction), physical dependence, or both, in someone who administers a drug periodically or continuously. Recreational drug abusers are at risk for occlusive and hemorrhagic stroke of diverse cause. Although sometimes over diagnosed, cerebral vasculitis has been historically verified in users of legal and illegal drugs. PMID- 9367975 TI - Autoimmune diabetic neuropathy. AB - Recent work has shown that inflammatory vasculopathy is commonly seen in biopsies of diabetic patients with neuropathy. Most of these patients have had syndromes consistent with proximal diabetic neuropathy or amyotrophy. This suggests that inflammatory vasculopathy is important in the pathogenesis of these disorders. Immunosuppressive therapy may benefit many of these patients. PMID- 9367976 TI - Therapy of systemic vasculitis. AB - The systemic vasculitides represent a highly heterogeneous and complex set of disorders primarily mediated via immunologic mechanisms. Standard therapy of these diseases includes the use of glucocorticoids without the use of additional cytotoxic agents. Recent long term follow-up investigations of patients treated with combined therapy has revealed an alarming incidence of treatment-related toxicity. Currently recommended therapeutic regimens are designed to minimize such toxicity while maintaining disease control. New therapeutic agents with greater disease specificity and lower toxicity are now being examined. PMID- 9367977 TI - The control of septum formation in fission yeast. PMID- 9367978 TI - Conversion of dorsal from an activator to a repressor by the global corepressor Groucho. AB - The Dorsal morphogen acts as both an activator and a repressor of transcription in the Drosophila embryo to regulate the expression of dorsal/ventral patterning genes. Circumstantial evidence has suggested that Dorsal is an intrinsic activator and that additional factors (corepressors) convert it into a repressor. These corepressors, however, have previously eluded definitive identification. We show here, via the analysis of embryos lacking the maternally encoded Groucho corepressor and via protein-binding assays, that recruitment of Groucho to the template by protein:protein interactions is required for the conversion of Dorsal from an activator to a repressor. Groucho is therefore a critical component of the dorsal/ventral patterning system. PMID- 9367979 TI - The Cdc42 GTPase-associated proteins Gic1 and Gic2 are required for polarized cell growth in Saccharomyces cerevisiae. AB - BEM2 of Saccharomyces cerevisiae encodes a Rho-type GTPase-activating protein that is required for proper bud site selection at 26 degrees C and for bud emergence at elevated temperatures. We show here that the temperature-sensitive growth phenotype of bem2 mutant cells can be suppressed by increased dosage of the GIC1 gene. The Gic1 protein, together with its structural homolog Gic2, are required for cell size and shape control, bud site selection, bud emergence, actin cytoskeletal organization, mitotic spindle orientation/positioning, and mating projection formation in response to mating pheromone. Each protein contains a CRIB (Cdc42/Rac-interactive binding) motif and each interacts in the two-hybrid assay with the GTP-bound form of the Rho-type Cdc42 GTPase, a key regulator of polarized growth in yeast. The CRIB motif of Gic1 and the effector domain of Cdc42 are required for this association. Genetic experiments indicate that Gic1 and Gic2 play positive roles in the Cdc42 signal transduction pathway, probably as effectors of Cdc42. Subcellular localization studies with a functional green fluorescent protein-Gic1 fusion protein indicate that this protein is concentrated at the incipient bud site of unbudded cells, at the bud tip and mother-bud neck of budded cells, and at cortical sites on large-budded cells that may delimit future bud sites in the two progeny cells. The ability of Gic1 to associate with Cdc42 is important for its function but is apparently not essential for its subcellular localization. PMID- 9367980 TI - Novel Cdc42-binding proteins Gic1 and Gic2 control cell polarity in yeast. AB - Cdc42p, a Rho-related GTP-binding protein, regulates cytoskeletal polarization and rearrangements in eukaryotic cells, but the effectors mediating this control remain unknown. Through the use of the complete yeast genomic sequence, we have identified two novel Cdc42p targets, Gic1p and Gic2p, which contain consensus Cdc42/Rac interactive-binding (CRIB) domains and bind specifically to Cdc42p-GTP. Gic1p and Gic2p colocalize with Cdc42p as cell polarity is established during the cell cycle and during mating in response to pheromones. Cells deleted for both GIC genes exhibit defects in actin and microtubule polarization similar to those observed in cdc42 mutants. Finally, the interaction of the Gic proteins and Cdc42p is essential, as mutations in the CRIB domain of Gic2p that eliminate Cdc42p binding disrupt Gic2p localization and function. Thus, Gic1p and Gic2p define a novel class of Cdc42p targets that are specifically required for cytoskeletal polarization in vivo. PMID- 9367981 TI - The Arabidopsis HY5 gene encodes a bZIP protein that regulates stimulus-induced development of root and hypocotyl. AB - Plant developmental processes are controlled by both endogenous programs and environmental stimuli. As a photomorphogenetic mutant, hy5 of Arabidopsis has been isolated and characterized. Our detailed characterization has revealed that the mutant is deficient in a variety of stimulus responses, including gravitropic response and waving growth of roots, as well as light-dependent hypocotyl elongation. In the roots and hypocotyl, the hy5 mutation also affects greening and specific cell proliferation such as lateral root formation and secondary thickening. Those phenotypes indicate that the HY5 gene is responsible for the regulation of fundamental developmental processes of the plant cell: cell elongation, cell proliferation, and chloroplast development. Molecular cloning of the HY5 gene using a T-DNA-tagged mutant has revealed that the gene encodes a protein with a bZIP motif, one of the motifs found in transcriptional regulators. Nuclear localization of the HY5 protein strongly suggests that the HY5 gene modulates the signal transduction pathways under the HY5-related development by controlling expression of genes downstream of these pathways. PMID- 9367982 TI - The LKLF transcription factor is required for normal tunica media formation and blood vessel stabilization during murine embryogenesis. AB - The transcriptional programs that regulate blood vessel formation are largely unknown. In this paper, we examine the role of the zinc finger transcription factor LKLF in murine blood vessel morphogenesis and homeostasis. By in situ hybridization and immunohistochemistry, we show that LKLF is expressed as early as embryonic day 9.5 (E9.5) in vascular endothelial cells throughout the developing mouse embryo. To better understand the function of LKLF, we used homologous recombination in embryonic stem (ES) cells to generate LKLF-deficient (LKLF-/-) mice. Both angiogenesis and vasculogenesis were normal in the LKLF-/- mice. However, LKLF-/- embryos died between E12.5 and E14.5 from severe intra embryonic and intra-amniotic hemorrhaging. This bleeding disorder was associated with specific defects in blood vessel morphology. Umbilical veins and arteries in the LKLF-/- embryos displayed an abnormally thin tunica media and aneurysmal dilatation before rupturing into the amniotic cavity. Similarly, vascular smooth muscle cells in the aortae from the LKLF-/- animals displayed a cuboidal morphology and failed to organize into a compact tunica media. Consistent with these findings, electron microscopic analyses demonstrated endothelial cell necrosis, significant reductions in the number of vessel-wall pericytes and differentiating smooth muscle cells, and decreased deposition of extracellular matrix in the LKLF-/- vessels. Despite these defects, in situ hybridization demonstrated normal expression of platelet-derived growth factor B, Tie1, Tie2, transforming growth factor beta, and heparin-binding epidermal growth factor in the vasculature of the LKLF-/- embryos. Therefore, LKLF defines a novel transcriptional pathway in which endothelial cells regulate the assembly of the vascular tunica media and concomitant vessel wall stabilization during mammalian embryogenesis. PMID- 9367983 TI - Mechanism of synergy between TATA and initiator: synergistic binding of TFIID following a putative TFIIA-induced isomerization. AB - The TFIID complex interacts with at least three types of core promoter elements within protein-coding genes, including TATA, initiator (Inr), and downstream promoter elements. We have begun to explore the mechanism by which the TFIID-Inr interaction leads to functional synergy between TATA and Inr elements during both basal and activated transcription. In DNase I footprinting assays, GAL4-VP16 recruited TFIID-TFIIA to core promoters containing either a TATA box, an Inr, or both TATA and Inr elements, with synergistic interactions apparent on the TATA Inr promoter. Appropriate spacing between the two elements was essential for the synergistic binding. Despite the sequence-specific TFIID-Inr interactions, gel shift experiments revealed that TFIID alone possesses similar affinities for the TATA-Inr and TATA promoters. Interestingly, however, recombinant TFIIA strongly and selectively enhanced TFIID binding to the TATA-Inr promoter, with little effect on binding to the TATA promoter. Studies of the natural adenovirus major late promoter confirmed these findings, despite the existence of specific but nonfunctional TFIID interactions downstream of the Inr in that promoter. These results suggest that a TFIIA-induced conformational change is essential for the sequence-specific TFIID-Inr interaction to occur with sufficient affinity to support the functional synergism between TATA and Inr elements. PMID- 9367984 TI - The downstream core promoter element, DPE, is conserved from Drosophila to humans and is recognized by TAFII60 of Drosophila. AB - We analyzed the function of the downstream promoter element (DPE), a distinct 7 nucleotide core promoter element that is approximately 30 nucleotides downstream of the transcription start site of many TATA-box-deficient (TATA-less) promoters in Drosophila. There is a strict requirement for spacing between the Inr and DPE motifs, as an increase or decrease of 3 nucleotides in the distance between the Inr and DPE causes a seven- to eightfold reduction in transcription as well as a significant reduction in the binding of purified TFIID. These results suggest a specific and somewhat rigid interaction of TFIID with the Inr and DPE sequences. Photo-cross-linking analysis of purified TFIID with a TATA-less DPE-containing promoter revealed specific cross-linking of dTAFII60 and dTAFII40 to the DPE, with a higher efficiency of cross-linking to dTAFII60 than to dTAFII40. These data, combined with the previously well-characterized interactions between the two TAFs and their homology to histones H4 and H3, suggest that a dTAFII60 dTAFII40 heterotetramer binds to the DPE. Human and Drosophila transcription factors exhibit essentially the same requirements for DPE sequence and for Inr DPE spacing. In addition, the TATA-less promoter of the human interferon regulatory factor-1 (IRF-1) gene contains a DPE that is important for transcriptional activity both in vitro and in cultured cells. Hence, these studies provide evidence for a direct role of TAFs in basal transcription of TATA less DPE-containing genes and collectively indicate that the DPE is, in many respects, a downstream counterpart to the TATA box that is present in Drosophila to humans. PMID- 9367985 TI - Rad53-dependent phosphorylation of Swi6 and down-regulation of CLN1 and CLN2 transcription occur in response to DNA damage in Saccharomyces cerevisiae. AB - Budding yeast possesses a checkpoint-dependent mechanism of delaying G1 progression in response to UV and ionizing radiation DNA damage. We have shown that after a pulse of DNA damage in G1 with the alkylating agent MMS, there is also a MEC1-, RAD53-, and RAD9-dependent delay in G1. This delay occurs at or before Start, as the MMS-treated cells do not bud, remain sensitive to alpha factor, and have low CLN1 and CLN2 transcript levels for a longer time than untreated cells. We further show that MMS directly and reversibly down-regulates CLN1 and CLN2 transcript levels. The initial drop in CLN transcript levels in MMS is not RAD53 dependent, but the kinetics of reaccumulation of CLN messages as cells recover from the damage is faster in rad53-11 cells than in wild type cells. This is not an indirect effect of faster progression through G1, because CLN transcripts reaccumulate faster in rad53-11 mutants arrested in G1 as well. In addition, the recovery of CLN mRNA levels can be also hastened by a SWI6 deletion or by overexpression of the truncated Swi4 (Swi4-t) that lacks the carboxy-terminal domain through which Swi4 associates with Swi6. This indicates that both Rad53 and Swi6 are negative regulators of CLN expression after DNA damage. Finally, Swi6 undergoes an MMS-inducible, RAD53-dependent phosphorylation in G1 cells, and Rad53, immunoprecipitated from MMS-treated cells, phosphorylates Swi6 in vitro. On the basis of these observations, we suggest that the Rad53 dependent phosphorylation of Swi6 may delay the transition to S phase by inhibiting CLN transcription. PMID- 9367986 TI - Phosphorylation- and ubiquitin-dependent degradation of the cyclin-dependent kinase inhibitor Far1p in budding yeast. AB - Cyclin-dependent kinase inhibitors (CKIs) play key roles in controlling the eukaryotic cell cycle by coordinating cell proliferation and differentiation. Understanding the roles of CKIs requires knowledge of how they are regulated both through the cell cycle and in response to extracellular signals. Here we show that the yeast CKI, Far1p, is controlled by ubiquitin-dependent proteolysis. Wild type Far1p was stable only in the G1 phase of the cell cycle. Biochemical and genetic evidence indicate that its degradation required the components of the G1 S ubiquitination system, Cdc34p, Cdc4p, Cdc53p, and Skp1p. We isolated a mutant form of Far1p (Far1p-22) that was able to induce cell cycle arrest in the absence of alpha-factor. Cells that overexpress Far1-22p arrested in G1 as large unbudded cells with low Cdc28p-Clnp kinase activity. Wild-type Far1p, but not Far1-22p, was readily ubiquitinated in vitro in a CDC34- and CDC4-dependent manner. Far1 22p harbors a single amino acid change, from serine to proline at residue 87, which alters phosphorylation by Cdc28p-Cln2p in vitro. Our results show that Far1p is regulated by ubiquitin-mediated proteolysis and suggest that phosphorylation of Far1p by the Cdc28p-Clnp kinase is part of the recognition signal for ubiquitination. PMID- 9367987 TI - Mechanism of active site exclusion in a site-specific recombinase: role of the DNA substrate in conferring half-of-the-sites activity. AB - The Flp site-specific recombinase assembles its active site by recruiting the catalytic tyrosine (Tyr-343) from one Flp monomer into the pro-active site containing a triad of Arg-191, His-305, and Arg-308 from a second monomer. In principle, two active sites may be assembled from a Flp dimer by simultaneous, reciprocal contribution of the shared amino acids by its constituent monomers. In practice, only one of the two active sites is assembled at a time, as would be consistent with a recombination mechanism involving two steps of single-strand exchanges. By using substrates containing strand-specific base bulges, we demonstrate that the relative disposition of their DNA arms can account for this active site exclusion. We also show that the exclusion mechanism operates only at the level of positioning Tyr-343 with respect to the pro-active site, and not at the level of orienting the labile phosphodiester bond within the DNA chain. It is not negative cooperativity of substrate binding but, rather, the substrate induced negative cooperativity in protein orientation that accomplishes half-of the-sites activity in the Flp system. PMID- 9367988 TI - Groucho acts as a corepressor for a subset of negative regulators, including Hairy and Engrailed. AB - Relatively little is known about the molecular mechanisms involved in transcriptional repression, despite its importance in development and differentiation. Recent evidence suggests that some transcriptional repressors act by way of adaptor molecules known as corepressors. Here, we use in vivo functional assays to test whether different repressor activities are mediated by the Groucho (Gro) corepressor in the Drosophila embryo. Previously, Gro was proposed to mediate repression by the Hairy-related family of basic helix-loop helix proteins. Our results indicate not only that repression by Hairy requires Gro, but that a repressor domain from the Engrailed (En) homeodomain protein is also Gro dependent. The latter result correlates with an ability of this En domain to bind to Gro in vitro. In contrast, repressor regions from the Even skipped, Snail, Kruppel, and Knirps transcription factors are effective in the absence of Gro. These results show that Gro is not generally required for repression, but acts as a specific corepressor for a fraction of negative regulators, including Hairy and En. PMID- 9367989 TI - u-shaped encodes a zinc finger protein that regulates the proneural genes achaete and scute during the formation of bristles in Drosophila. AB - The pattern of the large sensory bristles on the notum of Drosophila arises as a consequence of the expression of the achaete and scute genes. The gene u-shaped encodes a novel zinc finger that acts as a transregulator of achaete and scute in the dorsal region of the notum. Viable hypomorphic u-shaped mutants display additional dorsocentral and scutellar bristles that result from overexpression of achaete and scute. In contrast, overexpression of u-shaped causes a loss of achaete-scute expression and consequently a loss of dorsal bristles. The effects on the dorsocentral bristles appear to be mediated through the enhancer sequences that regulate achaete and scute at this site. The effects of u-shaped mutants are similar to those of a class of dominant alleles of the gene pannier with which they display allele-specific interactions, suggesting that the products of both genes cooperate in the regulation of achaete and scute. A study of the sites at which the dorsocentral bristles arise in mosaic u-shaped nota, suggests that the levels of the u-shaped protein are crucial for the precise positioning of the precursors of these bristles. PMID- 9367991 TI - Protein disulfide isomerase and assisted protein folding. PMID- 9367990 TI - Transcriptional activity of pannier is regulated negatively by heterodimerization of the GATA DNA-binding domain with a cofactor encoded by the u-shaped gene of Drosophila. AB - The genes pannier (pnr) and u-shaped (ush) are required for the regulation of achaete-scute during establishment of the bristle pattern in Drosophila. pnr encodes a protein belonging to the GATA family of transcription factors, whereas ush encodes a novel zinc finger protein. Genetic interactions between dominant pnr mutants bearing lesions situated in the amino-terminal zinc finger of the GATA domain and ush mutants have been described. We show here that both wild-type Pannier and the dominant mutant form activate transcription from the heterologous alpha globin promoter when transfected into chicken embryonic fibroblasts. Furthermore, Pnr and Ush are found to heterodimerize through the amino-terminal zinc finger of Pnr and when associated with Ush, the transcriptional activity of Pnr is lost. In contrast, the mutant pnr protein with lesions in this finger associates only poorly with Ush and activates transcription even when cotransfected with Ush. These interactions have been investigated in vivo by overexpression of the mutant and wild-type proteins. The results suggest an antagonistic effect of Ush on Pnr function and reveal a new mode of regulation of GATA factors during development. PMID- 9367992 TI - A family of putative tumor suppressors is structurally and functionally conserved in humans and yeast. AB - In Saccharomyces cerevisiae the CDC14 gene is essential for cell cycle progression. Strains carrying the cdc14-1(ts) allele enter the cell cycle and arrest at restrictive temperatures. We have identified two human cDNAs encoding proteins which share sequence identity to the yeast CDC14p. The cell cycle arrest in cdc14-1(ts) can be specifically complemented by the human cDNAs suggesting that they are functionally equivalent to the yeast CDC14 gene. Another clone identified in the search for human CDC14-like proteins corresponded to the putative tumor suppressor gene PTEN/MMAC1 (phosphatase and tensin homologue deleted on chromosome 10 or mutated in multiple advanced cancers 1). Analysis of the PTEN/MMAC1 showed that it did not complement the cdc14-1(ts) allele and that it is more closely related to the yeast open reading frame YNL128W. Human CDC14p and PTEN/MMAC1 were expressed as recombinant proteins, and both were shown to have kinetic properties characteristic of dual specific phosphatases. The human CDC14p was localized in the nucleus while PTEN/MMAC1 has been reported to be localized in the cytoplasm. Our results suggest that CDC14 and YNL128W/PTEN/MMAC1 represent two related, but distinct, families of human and yeast phosphatases. PMID- 9367993 TI - Noc2, a putative zinc finger protein involved in exocytosis in endocrine cells. AB - We have cloned a cDNA encoding a novel protein of 302 amino acids (designated Noc2, no C2 domain) that has 40.7% amino acid identity with and 77.9% similarity to the N-terminal region of rabphilin-3A, a target molecule of Rab3A. However, unlike rabphilin-3A, Noc2 lacks two C2 domains that are thought to interact with Ca2+ and phospholipids. Noc2 is expressed predominantly in endocrine tissues and hormone-secreting cell lines and at very low levels in brain. Immunoblot analysis of subcellular fractions of the insulin-secreting cell line MIN6 and immunocytochemistry reveal that Noc2 is a 38-kDa protein present in the cytoplasm. Overexpression of Noc2 in PC12 cells cotransfected with growth hormone enhances high K+-induced growth hormone secretion. Screening a mouse embryonic cDNA library with the yeast two-hybrid system shows that Noc2 interacts with the LIM domain-containing protein zyxin, a component of the cytoskeleton, and this interaction is further confirmed by the coimmunoprecipitation experiment. Accordingly, Noc2 is probably involved in regulated exocytosis in endocrine cells by interacting with the cytoskeleton. PMID- 9367994 TI - Cell adhesion to phosphatidylserine mediated by a product of growth arrest specific gene 6. AB - Gas6, a product of a growth arrest-specific gene 6, potentiates proliferation of vascular smooth muscle cells and prevents cell death of vascular smooth muscle cells. It has been also demonstrated that Gas6 is a ligand of receptor tyrosine kinases Axl, Sky, and Mer. Gas6 contains gamma-carboxyglutamic acid residues, which are found in some blood coagulation factors and mediate the interaction of the coagulation factors with negatively charged phospholipid. In this study, we clarified that Gas6 specifically bound to phosphatidylserine and the binding was dependent on Ca2+ and gamma-carboxyglutamic acid residues. Furthermore, we found that U937 cells, which express Gas6 receptor on their surfaces, adhered to phosphatidylserine-coated enzyme-linked immunosorbent assay (ELISA) plate only in the presence of Gas6 and Ca2+. U937 cells also bound to ELISA plate coated with phosphatidylinositol, but the binding was independent of Gas6 and Ca2+. On the other hand, U937 cells did not adhere to phosphatidylcholine- or phosphatidylethanolamine-coated ELISA plate even in the presence of Gas6 and Ca2+. These findings suggest that Gas6 may play a role in recognition of cells exposing phosphatidylserine on their surfaces by phagocytic cells, which is supposed to be one of the mechanisms for clearing dying cells. PMID- 9367995 TI - The calcium/calmodulin-dependent protein phosphatase calcineurin is the major Elk 1 phosphatase. AB - The transcription factor Elk-1 is a component of ternary complex factor and regulates gene expression in response to a wide variety of extracellular stimuli. Phosphorylation of the C-terminal domain of Elk-1, especially at serine 383, is important for its transactivation activity. Recently mitogen-activated protein kinases, such as extracellular signal-regulated kinase, stress-activated protein kinase, and p38 mitogen-activated protein kinase have been demonstrated to be Elk 1 kinases. However, negative regulators of Elk-1, such as protein phosphatases, still remain to be identified. Here we report that COS cell lysates were able to dephosphorylate an extracellular signal-regulated kinase-phosphorylated glutathione S-transferase-Elkc fusion protein, including serine 383. The phosphatase activity was inhibited by cyclosporin A (a calcineurin inhibitor) but not by okadaic acid (a PP1 and PP2A inhibitor). Purified calcineurin also could efficiently dephosphorylate glutathione S-transferase-Elkc in vitro. Pretreatment of COS cells with cyclosporin A significantly enhanced epidermal growth factor induced serine 383 Elk-1 phosphorylation whereas ionomycin inhibited the Elk-1 phosphorylation. These data provide both in vitro and in vivo evidence that calcineurin is the major Elk-1 phosphatase and plays a critical role in Elk-1 regulation. The identification of calcineurin as the major Elk-1 phosphatase may provide a mechanism for Elk-1 regulation by Ca2+ signals as well as a possible biochemical basis for the neurotoxicity and nephrotoxicity of the immunosuppressant drug cyclosporin A. PMID- 9367996 TI - Phosphorylation of IkappaB-alpha inhibits its cleavage by caspase CPP32 in vitro. AB - IkappaB proteins function as direct regulators of Rel/NF-kappaB transcription complexes. We show that the cell-death protease CPP32 (caspase-3) in vitro specifically cleaved chicken and human IkappaB-alpha at a conserved Asp-Ser sequence. This cleavage site appears to be identical to the site at which chicken IkappaB-alpha is cleaved in vivo in temperature-sensitive v-Rel-transformed chicken spleen cells undergoing apoptosis. Other caspases, namely interleukin 1beta-converting enzyme (caspase-1) and Ich-1 (caspase-2), did not cleave IkappaB alpha. CPP32 also cleaved mammalian IkappaB-beta in vitro at the analogous Asp Ser sequence. Cleavage of IkappaB-alpha by CPP32 was blocked by serine phosphorylation of IkappaB-alpha. Cleavage of IkappaB-alpha by a CPP32- like protease could generate a constitutive inhibitor of Rel transcription complexes. This report provides evidence for a direct biochemical interaction between the NF kappaB signaling pathway and a cell-death protease signaling pathway. PMID- 9367997 TI - Phenobarbital alters protein binding to the CYP2B1/2 phenobarbital-responsive unit in native chromatin. AB - Phenobarbital is a classical inducer of the drug metabolizing cytochrome P450 genes, but the molecular mechanism of induction has not been elucidated. Functional analyses have identified a phenobarbital-responsive unit in the rat CYP2B1/2 and mouse Cyp2b10 genes about -2.3 kilobase pairs from the transcriptional start site, but little or no changes in protein binding to this region were observed in vitro. To examine the role of chromatin structure, protein binding to the phenobarbital-responsive unit assessed by in vitro DNase I footprinting was compared with that assessed by DNase I in vivo footprints in native chromatin. A region centered on a putative nuclear factor-1 site was the major protected region in in vitro footprints, and there were no detectable differences in binding between extracts from control and phenobarbital-treated animals. In contrast, phenobarbital treatment dramatically altered the protection pattern in native chromatin. In control samples a core region of about 25 base pairs (bp) centered on the nuclear factor-1 site was protected. However, after phenobarbital treatment, the protection of this core region was increased, and more dramatically the region of protection was extended 20 bp to either side so that a total of about 60 bp were protected. These results provide the first evidence that phenobarbital treatment alters the composition or architecture of proteins binding to the phenobarbital-responsive unit region and indicate that chromatin structure is important in this process. Because proteins are bound to the region in the untreated animal, the mechanism of induction involves the activation of proteins bound to the region and possibly recruitment of additional regulatory proteins rather than conversion of a closed chromatin structure to an open one that can bind regulatory factors. PMID- 9367998 TI - Phosphorylation of the N-formyl peptide receptor is required for receptor internalization but not chemotaxis. AB - The human N-formyl peptide receptor (FPR) is a member of the family of leukocyte, G protein-coupled, chemoattractant receptors. To determine the role(s) of receptor phosphorylation in FPR processing and formylmethionylleucylphenylalanine (fMLF)-mediated chemotaxis, we utilized U937 cells expressing the recombinant wild type receptor and a mutant form of the FPR. This mutant, which lacks all of the serine and threonine residues in the C terminus of the receptor, DeltaST, has recently been shown to produce a receptor capable of fMLF binding and G protein activation but was demonstrated not to undergo fMLF-dependent phosphorylation or desensitization of the calcium mobilization response upon repeated exposure to agonist (Prossnitz, E. R. (1997) J. Biol. Chem. 272, 15213-15219). In this report, we examined the role of receptor phosphorylation in FPR internalization and leukocyte chemotaxis. Whereas the wild type receptor was rapidly internalized upon stimulation, the phosphorylation-deficient mutant was not, remaining entirely on the cell surface. In addition, contrary to the hypothesis that receptor processing and recycling are required for chemotaxis, we found no defect in the ability of the mutant FPR to migrate up a concentration gradient of fMLF. These results indicate that phosphorylation of the FPR is a necessary step in receptor internalization but that receptor phosphorylation, desensitization, and internalization are not required for chemotaxis. PMID- 9367999 TI - A 50-picosiemens anion channel of the chloroplast envelope is involved in chloroplast protein import. AB - Single channel recordings were used to investigate the changes on the pea chloroplast envelope during protein import. In the inside-out patch configuration a 50-picosiemens (pS) anion channel of the chloroplast envelope membrane was identified. The open time probability of the channel was decreased by the addition of the wild type precursor protein of ferredoxin (wt-prefd) to the pipette-filling solution in the presence of 0.5 mM ATP. In the absence of ATP or in the presence of 50 microM ATP, wt-prefd did not affect the open time probability of the channel. A deletion mutant of prefd, Delta6-14-prefd, which is inactive in in vitro import, was also unable to affect the open time probability of the 50-pS anion channel. In the presence of 100 microM ATP, wt-prefd decreased the open time probability of the channel to a lesser extent, as did the transit peptide alone. It is concluded that the 50-pS anion channel could be part of the protein import machinery of the inner membrane. In addition the precursor protein under import conditions induced burst-like increases of the envelope conductivity. The implication of both responses for the chloroplast protein import process are discussed. PMID- 9368000 TI - The role of pp60c-src in the regulation of calcium entry via store-operated calcium channels. AB - In many cell types, G protein-coupled receptors stimulate a transient Ca2+ release from internal stores followed by a sustained, capacitative Ca2+ entry, which is mediated by store-operated channels (SOCs). Although it is clear that SOCs are activated by depletion of internal Ca2+ stores, the mechanism for this process is not well understood. Previously, we have reported that inhibitors of tyrosine kinase activity block the bradykinin- and thapsigargin-stimulated Ca2+ entry in fibroblasts, suggesting that a tyrosine kinase activity may be involved in relaying the message from the empty internal Ca2+ stores to the plasma membrane Ca2+ channel (Lee, K.-M., Toscas, K., and Villereal, M. L. (1993) J. Biol. Chem. 268, 9945-9948). We also have demonstrated that bradykinin activates the nonreceptor tyrosine kinase c-src (Lee, K.-M., and Villereal, M. L. (1996) Am. J. Physiol. 270, C1430-C1437). We investigated whether c-src plays a role in the regulation of SOCs by monitoring capacitative Ca2+ entry in 3T3-like embryonic fibroblast lines derived from either wild type or src-/src- (Src-) transgenic mice. We report that Ca2+ entry, following store depletion by either bradykinin or thapsigargin, is dramatically lower in Src- fibroblasts than in wild type fibroblasts. The level of capacitative Ca2+ entry in Src- cells is restored to nearly normal levels by transfecting Src- cells with chicken c-src. These data suggest that c-src may play a major role in the regulation of SOCs. PMID- 9368001 TI - The constitutively active mutant Galpha13 transforms mouse fibroblast cells deficient in insulin-like growth factor-I receptor. AB - Insulin-like growth factor-I (IGF-I) receptor plays an important role in normal cell cycle progression and tumor growth, and it is thought to be essential for cellular transformation. To test this hypothesis, we stably transfected a GTPase deficient mutant human Galpha13, which is highly oncogenic when overexpressed in vitro, into R- fibroblasts derived from IGF-I receptor-deficient mice. Northern blots of multiple clones revealed the expression of a 1.8-kilobase pair mutant Galpha13 transcript in transfected cells, in addition to the 6-kilobase pair endogenous mRNA. The transfection resulted in a doubling of the expression of Galpha13 protein in these cells as assessed by Western blot analysis. The transforming ability of the mutant Galpha13 was tested using the soft agar assay. Nontransfected R- cells cultured with 10% fetal bovine serum failed to form colonies after 3 weeks. Most of the mutant Galpha13-expressing clones formed significant numbers of colonies (11-50 colonies/1000 cells plated). Overexpression of the IGF-I receptor enabled R- cells to form colonies (27 colonies), and co-transfection of the mutant Galpha13 caused a further increase in colony formation (117-153 colonies) in three of five clones analyzed. Apparently Galpha13 works through pathways other than mitogen-activated protein kinase and c-Jun N-terminal kinase in transforming R- cells, because their activities were not significantly altered by the mutant Galpha13 expression. These results demonstrate that Galpha13 can induce cellular transformation through pathways apparently independent of the IGF-I receptor and that activation of the IGF-I receptor signaling pathways, although not essential for the transforming phenotype, enhances the effect of other pathways. PMID- 9368002 TI - The Ov20 protein of the parasitic nematode Onchocerca volvulus. A structurally novel class of small helix-rich retinol-binding proteins. AB - Ov20 is a major antigen of the parasitic nematode Onchocerca volvulus, the causative agent of river blindness in humans, and the protein is secreted into the tissue occupied by the parasite. DNA encoding Ov20 was isolated, and the protein was expressed in Escherichia coli. Fluorescence-based ligand binding assays show that the protein contains a high affinity binding site for retinol, fluorescent fatty acids (11-((5-dimethylaminonaphthalene-1 sulfonyl)amino)undecanoic acid, dansyl-DL-alpha-aminocaprylic acid, and parinaric acid) and, by competition, oleic and arachidonic acids, but not cholesterol. The fluorescence emission of dansylated fatty acids is significantly blue-shifted upon binding in comparison to similarly sized beta-sheet-rich mammalian retinol- and fatty acid-binding proteins. Secondary structure prediction algorithms indicate that a alpha-helix predominates in Ov20, possibly in a coiled coil motif, with no evidence of beta structures, and this was confirmed by circular dichroism. The protein is highly stable in solution, requiring temperatures in excess of 90 degrees C or high denaturant concentrations for unfolding. Ov20 therefore represents a novel class of small retinol-binding protein, which appears to be confined to nematodes. The retinol binding activity of Ov20 could possibly contribute to the eye defects associated with onchocerciasis and, because there is no counterpart in mammals, represents a strategic target for chemotherapy. PMID- 9368003 TI - Specific proteolysis of the kinase protein kinase C-related kinase 2 by caspase-3 during apoptosis. Identification by a novel, small pool expression cloning strategy. AB - The caspase family of proteases plays a critical role in the execution of apoptosis. However, efforts to decipher the molecular mechanisms by which caspases induce cell death have been greatly hindered by the lack of systematic and broadly applicable strategies to identify their substrates. Here we describe a novel expression cloning strategy to rapidly isolate cDNAs encoding caspase substrates that are cleaved during apoptosis. Small cDNA pools (approximately 100 clones each) are transcribed/translated in vitro in the presence of [35S]methionine; these labeled protein pools are then incubated with cytosolic extracts from control and apoptotic cells. cDNA pools encoding proteins that are specifically cleaved by the apoptotic extract and whose cleavage is prevented by the caspase inhibitor acetyl-Tyr-Val-Ala-Asp chloromethylketone are subdivided and retested until a single cDNA is isolated. Using this approach, we isolated a partial cDNA encoding protein kinase C-related kinase 2 (PRK2), a serine threonine kinase, and demonstrate that full-length human PRK2 is proteolyzed by caspase-3 at Asp117 and Asp700 in vitro. In addition, PRK2 is cleaved rapidly during Fas- and staurosporine-induced apoptosis in vivo by caspase-3 or a closely related caspase. Both of the major apoptotic cleavage sites of PRK2 in vivo lie within its regulatory domain, suggesting that its activity may be deregulated by proteolysis. PMID- 9368005 TI - The disulfide bonds in the C-terminal domains of the human insulin receptor ectodomain. AB - The human insulin receptor is a homodimer consisting of two monomers linked by disulfide bonds. Each monomer comprises an alpha-chain that is entirely extracellular and a beta-chain that spans the cell membrane. The alpha-chain has a total of 37 cysteine residues, most of which form intrachain disulfide bonds, whereas the beta-chain contains 10 cysteine residues, four of which are in the extracellular region. There are two classes of disulfide bonds in the insulin receptor, those that can be reduced under mild reducing conditions to give alpha beta monomers (class I) and those that require stronger reducing conditions (class II). The number of class I disulfides is small and includes the alpha alpha dimer bond Cys524. In this report we describe the use of cyanogen bromide and protease digestion of the exon 11 plus form of the receptor ectodomain to identify disulfide linkages between the beta-chain residues Cys798 and Cys807 and between the alpha-chain Cys647 and the beta-chain Cys872. The latter bond is the sole alpha-beta link in the molecule and implies a side-by-side alignment of the two fibronectin III domains of the receptor. Also presented is evidence for additional alpha-alpha dimer bond(s) involving at least one of the cysteine residues of the triplet at positions 682, 683, and 685. Evidence is also presented to show that Cys884 exists as a buried thiol in the soluble ectodomain. PMID- 9368004 TI - Structure of the photoreactive iron center of the nitrile hydratase from Rhodococcus sp. N-771. Evidence of a novel post-translational modification in the cysteine ligand. AB - Nitrile hydratase (NHase) from Rhodococcus sp. N-771 is a photoreactive enzyme that is inactivated by nitrosylation of the non-heme iron center and activated by photodissociation of nitric oxide (NO). To obtain structural information on the iron center, we isolated peptide complexes containing the iron center by proteolysis. When the tryptic digest of the alpha subunit isolated from the inactive form was analyzed by reversed-phase high performance liquid chromatography, the absorbance characteristic of the nitrosylated iron center was observed in the peptide fragment, Asn105-Val-Ile-Val-Cys-Ser-Leu-Cys-Ser-Cys-Thr Ala-Trp-Pro-Ile-Leu - Gly-Leu-Pro-Pro-Thr-Trp-Tyr-Lys128. The peptide contained 0.79 mol of iron/mol of molecule as well as endogenous NO. Subsequently, by digesting the peptide with thermolysin, carboxypeptidase Y, and leucine aminopeptidase M, we found that the minimum peptide segment required for the nitrosylated iron center is the 11 amino acid residues from alphaIle107 to alphaTrp117. Furthermore, by using mass spectrometry, protein sequence, and amino acid composition analyses, we have shown that the 112th Cys residue of the alpha subunit is post-translationally oxidized to a cysteine-sulfinic acid (Cys-SO2H) in the NHase. These results indicate that the NHase from Rhodococcus sp. N-771 has a novel non-heme iron enzyme containing a cysteine-sulfinic acid in the iron center. Possible ligand residues of the iron center are discussed. PMID- 9368006 TI - Interaction between cell cycle regulator, E2F-1, and NF-kappaB mediates repression of HIV-1 gene transcription. AB - The NF-kappaB/Rel family of transcription factors is one of the main targets of cytokines and other agents that induce HIV-1 gene expression. Some of these extracellular stimuli arrest cells in the G1 phase of the mitotic division cycle and modulate the activity of the tumor suppressor protein Rb and its partner E2F 1. Earlier studies indicated that E2F-1, a transcription factor that stimulates expression of S-phase-specific genes, is able to repress transcription directed by the human immunodeficiency virus (HIV-1) type-1 promoter in a variety of cells, including those of glial and lymphocytic origin. Here, we demonstrate that E2F-1 may regulate the activity of the HIV-1 long terminal repeat through its ability to bind sequences in the NF-kappaB enhancer region and to interact with the NF-kappaB subunit, p50. Gel retardation and methylation interference assays show that E2F-1 is able to bind specifically to a site embedded within the two NF kappaB elements. Gel retardation/immunoblot analysis using purified E2F-1 and p50 homodimers reveals the presence of complexes containing both proteins. Affinity chromatography and co-immunoprecipitation assays provide evidence for direct interaction of E2F-1 and p50 in the absence of their DNA target sequences. In vitro transcription assay demonstrates that E2F-1 represses NF-kappaB mediated transcription in a cell-free system. Functional studies in Jurkat T lymphocytic cells point to the importance of both the E2F and NF-kappaB binding sites in E2F 1 mediated repression of HIV-1 promoter, in vivo. The results of this study suggest that NF-kappaB activity may be regulated by its interaction with the cell cycle regulatory protein, E2F-1. PMID- 9368008 TI - HER-2/neu is rate-limiting for ovarian cancer growth. Conditional depletion of HER-2/neu by ribozyme targeting. AB - Amplification and overexpression of the HER-2/neu proto-oncogene frequently coincide with an aggressive clinical course of certain human adenocarcinomas. To assess whether HER-2/neu plays a rate-limiting role in ovarian cancer, we used human SK-OV-3 ovarian cancer cells as a model. We applied a conditional mRNA depletion strategy of HER-2/neu with anti-HER-2/neu-targeted hammerhead ribozymes expressed under the control of a tetracycline-regulated promoter system. In these ovarian cancer cells, we reduced HER-2/neu mRNA, protein expression, and tumor growth in nude mice by transfection with HER-2/neu-targeted ribozymes and generated cell lines expressing different levels of HER-2/neu. Expression of the most effective ribozyme (Rz3) quenched HER-2/neu mRNA levels by >90%. Concomitantly, fluorescence-activated cell sorting analysis revealed that expression of the HER-2/neu-encoded surface glycoprotein was almost completely abrogated. In nude mice, tumor growth was dramatically inhibited in the HER-2/neu depleted Rz3-expressing SK-OV-3 cells. Furthermore, already established tumors started to regress when Rz3 expression was activated midstream by withdrawal of the tetracycline treatment. This study supports the thesis that HER-2/neu can be rate-limiting for the malignant phenotype of ovarian cancer in a gene dose dependent manner. PMID- 9368007 TI - Fibroblast growth factor 3, a protein with dual subcellular localization, is targeted to the nucleus and nucleolus by the concerted action of two nuclear localization signals and a nucleolar retention signal. AB - The major isoform of fibroblast growth factor 3 (FGF3) is initiated from a CUG codon, and the resultant product is distributed to the nucleus/nucleolus and secretory pathway. This dual subcellular localization is achieved in part by the competing effects of two classical intracellular targeting signals located near the amino terminus. At the extreme amino terminus is a short stretch of 29 amino acids before a signal peptide necessary for translocation into the endoplasmic reticulum, which is next to an adjacent bipartite nuclear localization signal. The carboxyl-terminal region of FGF3 is also implicated in nuclear/nucleolar localization. We describe here the characterization of carboxyl-terminal signals by showing they are capable of directing a heterologous protein, beta galactosidase, to the nucleus. Furthermore, appending both the amino- and carboxyl-terminal domains onto beta-galactosidase, reproduces the dual subcellular localization properties of FGF3. Nuclear uptake of FGF3 appears to be signal-mediated since it binds to karyopherin alpha, the nuclear localization signal binding subunit of a heterodimeric receptor of the nuclear import machinery. The import of FGF3 into the nucleus is energy-dependent, and the inhibition of this process has demonstrated the importance of the nucleolar retention signal in nucleoplasmic and nucleolar accumulation. PMID- 9368009 TI - Human thyroperoxidase in its alternatively spliced form (TPO2) is enzymatically inactive and exhibits changes in intracellular processing and trafficking. AB - Thyroid peroxidase (TPO1) is a membrane-bound heme-containing glycoprotein that catalyzes the synthesis of thyroid hormones. We generated stable cell lines expressing TPO1 and the alternatively spliced isoform TPO2. Pulse-chase studies showed that TPO2 half-life was dramatically decreased as compared with TPO1. The sensitivity of TPO2 to endo-beta-N-acetylglucosaminidase H indicated that the protein is processed through the endoplasmic reticulum and bears high mannose type structures. Cell surface biotinylation experiments showed that the two isoforms also differ in their intracellular trafficking. TPO2 was totally retained in the cell, whereas 15% of TPO1 reached the cell surface. The inability of TPO2 to come out of the intracellular compartments was related to structural changes in the molecule. Evidence of these changes was obtained through the lack of recognition of TPO2 by half of the 13 TPO monoclonal antibodies tested in immunoprecipitation experiments. Our data suggest that because of an improper folding, TPO2 is trapped in the endoplasmic reticulum and rapidly degraded. The failure of incorporation of [14C]aminolevulinic acid in the cultured cells showed that TPO2 did not bind to heme, whereas TPO1 did. This result was confirmed through a guaiacol assay showing that TPO2 is enzymatically inactive. PMID- 9368010 TI - Characterization of an N-acetylglucosamine-6-O-sulfotransferase from human respiratory mucosa active on mucin carbohydrate chains. AB - A microsomal GlcNAc-6-O-sulfotransferase activity from human bronchial mucosa, able to transfer a sulfate group from adenosine 3'-phosphate 5'-phosphosulfate onto methyl-N-acetylglucosaminides or terminal N-acetylglucosamine residues of carbohydrate chains from human respiratory mucins, has been characterized. The reaction products containing a terminal HO3S-6GlcNAc were identified by high performance anion-exchange chromatography. Using methyl-beta-N acetylglucosaminide as a substrate, the optimal activity was obtained with 0.1% Triton X-100, 30 mM NaF, 20 mM Mn2+, 5 mM AMP in a 30 mM MOPS (3-(N-morpholino) propanesulfonic acid) buffer at pH 6.7. The apparent Km values for adenosine 3' phosphate 5'-phosphosulfate and methyl-beta-N-acetylglucosaminide were observed at 9.1 x 10(-6) M and 0.54 x 10(-3) M, respectively. The enzyme had more affinity for carbohydrate chains with a terminal GlcNAc residue than for methyl-beta-N acetylglucosaminide; it was unable to catalyze the transfer of sulfate to position 6 of the GlcNAc residue contained in a terminal Galbeta1-4GlcNAc sequence. However, oligosaccharides with a nonreducing terminal HO3S-6GlcNAc were substrates for a beta1-4 galactosyltransferase from human bronchial mucosa. These data point out that GlcNAc-6-O-sulfotransferase must act before beta1-4 galactosylation in mucin-type oligosaccharide biosynthesis. PMID- 9368011 TI - Analysis of activation-induced conformational changes in p47phox using tryptophan fluorescence spectroscopy. AB - Activation of the neutrophil NADPH oxidase requires translocation of cytosolic proteins p47(phox), p67(phox), and Rac to the plasma membrane or phagosomal membrane, where they assemble with membrane-bound flavocytochrome b. During this process, it appears that p47(phox) undergoes conformational changes, resulting in the exposure of binding sites involved in assembly and activation of the oxidase. In the present study, we have directly evaluated activation-induced conformational changes in p47(phox) using tryptophan fluorescence and circular dichroism spectroscopy. Treatment of p47(phox) with amphiphilic agents known to activate the NADPH oxidase (SDS and arachidonic acid) caused a dose-dependent quenching in the intrinsic tryptophan fluorescence of p47(phox), whereas treatment with a number of other amphiphilic agents that failed to activate the oxidase had no effect on p47(phox) fluorescence. In addition, the concentration range of activating agents required to induce changes in fluorescence correlated with the concentration range of these agents that induced maximal NADPH oxidase activity in a cell-free assay system. We next determined if activation by phosphorylation caused the same type of conformational changes in p47(phox). Protein kinase C phosphorylation of p47(phox) in vitro resulted in comparable quenching of fluorescence, which also correlated directly with NADPH oxidase activity. Finally, the circular dichroism (CD) spectrum of p47(phox) was significantly changed by the addition of SDS, whereas treatment with a non activating detergent had no effect on the CD spectrum. These results support the conclusion that activation by amphiphilic agents results in changes in the secondary structure of p47(phox). Thus, our studies provide direct evidence linking conformational changes in p47(phox) to the NADPH oxidase activation/assembly process and also further support the hypothesis that amphiphile-mediated activation of the NADPH oxidase induces changes in p47(phox) that are similar to those mediated by phosphorylation in vivo. PMID- 9368012 TI - Subunit exchange of alphaA-crystallin. AB - alpha-Crystallin, the major protein in the mammalian lens, is a molecular chaperone that can bind denaturing proteins and prevent their aggregation. Like other structurally related small heat shock proteins, each alpha-crystallin molecule is composed of an average of 40 subunits that can undergo extensive reorganization. In this study we used fluorescence resonance energy transfer to monitor the rapid exchange of recombinant alpha-crystallin subunits. We labeled alphaA-crystallin with stilbene iodoacetamide (4-acetamido-4' ((iodoacetyl)amino)stilbene-2,2'-disulfonic acid), which serves as an energy donor and with lucifer yellow iodoacetamide, which serves as an energy acceptor. Upon mixing the two populations of labeled alphaA-crystallin, we observed a reversible, time-dependent decrease in stilbene iodoacetamide emission intensity and a concomitant increase in lucifer yellow iodoacetamide fluorescence. This result is indicative of an exchange reaction that brings the fluorescent alphaA crystallin subunits close to each other. We further showed that the exchange reaction is strongly dependent on temperature, with a rate constant of 0.075 min 1 at 37 degrees C and an activation energy of 60 kcal/mol. The subunit exchange is independent of pH and calcium concentration but decreases at low and high ionic strength, suggesting the involvement of both ionic and hydrophobic interactions. It is also markedly reduced by the binding of large denatured proteins. The degree of inhibition is directly proportional to the molecular mass and the amount of bound polypeptide, suggesting an interaction of several alphaA crystallin subunits with multiple binding sites of the denaturing protein. Our findings reveal a dynamic organization of alphaA-crystallin subunits, which may be a key factor in preventing protein aggregation during denaturation. PMID- 9368013 TI - A mercuric ion uptake role for the integral inner membrane protein, MerC, involved in bacterial mercuric ion resistance. AB - Bacterial detoxification of mercuric ion depends on the presence of one or more integral membrane proteins (MerT and/or MerC) whose postulated function is in transport of Hg2+ from a periplasmic Hg2+-binding protein (MerP) to cytoplasmic mercuric reductase. In this study, MerC from the Tn21-encoded mer operon was overexpressed and studied in vesicles and in purified form to clarify the role played by this protein in mercuric ion resistance. MerC-containing vesicles were found to take up mercuric ion independently of MerP. Since uptake correlated with the level of MerC expression was unaffected by osmotic pressure, and was only partially decreased in the presence of 0.05% Triton X-100, the observed uptake appears to represent mainly binding to MerC. Binding was inhibited by thiol specific reagents, consistent with an essential role for cysteine residues. The essential thiol groups were inaccessible to hydrophilic thiol reagents, whereas hydrophobic reagents completely abolished Hg2+ binding. These observations are consistent with the predicted topology of the protein, wherein all 4 cysteine residues are either in the cytoplasm or the bilayer. A role for MerC in Hg2+ transport is thus also likely. Based on these results, a modified model for bacterial Hg2+ transport is proposed. PMID- 9368014 TI - Expression of two myeloid cell-specific genes requires the novel transcription factor, c-fes expression factor. AB - The protein product of the c-fes proto-oncogene has been implicated in the normal development of myeloid cells (macrophages and granulocytes). We have previously shown that 151 base pairs of c-fes 5'-flanking sequences are sufficient for myeloid cell-specific expression and include functional binding sites for Sp1, PU.1, and a novel nuclear factor (Heydemann, A., Juang, G., Hennessy, K., Parmacek, M. S., and Simon, M. C. (1996) Mol. Cell. Biol. 16, 1676-1686). This novel hematopoietic transcription factor, termed FEF (c-fes expression factor), binds to a cis-acting element that is located at nucleotides -9 to -4 of the c fes promoter between two Ets binding sites (at -19 to -15 and -4 to +1) which bind PU.1. We now show that a FEF binding site exists in the myeloid cell specific regulatory region of a second gene, the -2.7-kilobase pair enhancer of chicken lysozyme. The lysozyme FEF site is immediately 5' to a PU. 1 site, analogous to their arrangement in the c-fes promoter, and allows the formation of a preliminary FEF consensus site, 5'-GAAT(C/G)A-3'. This consensus site does not match any sites for known transcription factors. Importantly, although PU.1 binds immediately 3' of the FEF site in both the c-fes promoter and the chicken lysozyme enhancer (CLE), we show that they bind independently. The FEF sites are required for high levels of transcription by both the CLE and the c-fes promoter in transient transfection experiments. Importantly, elimination of the CLE FEF site abolishes all transcriptional activity of this enhancer element. Mutation of the adjacent PU.1 site in either the c-fes promoter or the CLE, reduces activity by approximately 50%. Therefore, transcription of both lysozyme and fes in myeloid cells requires FEF and PU.1. UV cross-linking experiments show that the FEF binding activity consists of a single 70-kDa protein in both human and murine cell lines. FEF binding activity is not affected by antibodies that specifically recognize a number of cloned transcription factors. Collectively, these data indicate that we have identified a novel transcription factor that is functionally important for the expression of at least two myeloid cell-specific genes. PMID- 9368015 TI - Partitioning of proteins into plasma membrane microdomains. Clustering of mutant influenza virus hemagglutinins into coated pits depends on the strength of the internalization signal. AB - Internalization of membrane proteins involves their recruitment into plasma membrane clathrin-coated pits, with which they are thought to interact by binding to AP-2 adaptor protein complexes. To investigate the interactions of membrane proteins with coated pits at the cell surface, we applied image correlation spectroscopy to measure directly and quantitatively the clustering of influenza hemagglutinin (HA) protein mutants carrying specific cytoplasmic internalization signals. The HA system enables direct comparison between isolated internalization signals, because HA itself is excluded from coated pits. The studies presented here provide, for the first time, a direct quantitative measure for the degree of clustering of membrane proteins in coated pits at the cell surface. The degree of clustering depended on the strength of the internalization signal and on the integrity of the clathrin lattices and correlated with the internalization rates of the mutants. The clustering of the HA mutants fully correlated with their ability to co-precipitate alpha-adaptin from whole cells, the first such demonstration for a membrane protein that is not a member of the epidermal growth factor receptor family. Furthermore, both the clustering in coated pits and the co-precipitation with alpha-adaptin were dramatically reduced in the cold, suggesting that low temperature can interfere with the sorting of proteins into coated pits. In addition to the specific results reported here, the general applicability of the image correlation spectroscopy approach to study any process involving the clustering or oligomerization of membrane receptors at the cell surface is discussed. PMID- 9368016 TI - Recovery of Ca2+ pools and growth in Ca2+ pool-depleted cells is mediated by specific epoxyeicosatrienoic acids derived from arachidonic acid. AB - Depletion of Ca2+ pools using the irreversible Ca2+ pump blocker, thapsigargin, induces DDT1MF-2 smooth muscle cells to enter a stable nonproliferative state. Reversal of this state can be mediated by high (20%) serum treatment, which induces new Ca2+ pump protein, return of Ca2+ pools, and reentry of cells into the cell cycle; the effect of serum can be mimicked by the essential fatty acids (EFA), arachidonic, linoleic, and alpha-linolenic acids (Graber, M.N., Alfonso, A., and Gill, D.L., (1996) J. Biol. Chem. 271, 883-888). The possible requirement for EFA metabolism in inducing recovery of Ca2+ pool-depleted growth-arrested cells was investigated. Neither cyclooxygenase or lipoxygenase inhibitors had any effect on arachidonic acid-induced growth recovery of thapsigargin-treated cells. In contrast, the cytochrome P-450 epoxygenase inhibitors, SKF525A and metyrapone, substantially reduced arachidonic acid-induced recovery of growth while having minimal effects on control cell growth. Both epoxygenase inhibitors completely prevented the arachidonic acid-induced recovery of bradykinin-releasable Ca2+ pumping pools, whereas cyclooxygenase and lipoxygenase inhibitors had no effect. The effectiveness of the four cytochrome P-450 metabolites of arachidonic acid on recovery of Ca2+ pools were compared; 8,9- and 11,12-epoxyeicosatrienoic acid (EET) at 1.5 microM were completely effective in recovering agonist-sensitive Ca2+ pools, whereas the 5,6- and 14,15-EETs were without effect. SKF525A did not block the action of 8,9- or 11, 12-EET indicating further P-450 metabolism was not required. Hydration of the active EET molecules prevented Ca2+ pool recovery since the dihydroxy-derivatives of both 8,9- and 11,12-EET were ineffective. The specificity of effectiveness among EET molecules for subsequent resumption of growth of thapsigargin-treated cells was the same as for Ca2+ pool recovery. Significantly, the P-450 inhibitors, SKF525A and metyrapone, both prevented the action of 20% serum in inducing recovery of thapsigargin-treated cells, whereas cyclooxygenase and lipoxygenase inhibitors were ineffective, indicating that EFAs are the active component within serum that is responsible for recovery of Ca2+ pool-depleted cells. The specific action of EETs in mediating recovery of Ca2+ pools and growth of thapsigargin-treated cells represents not only a novel action of epoxygenase products from EFAs, but also a potentially significant new signaling pathway that may effect translational control and regulate transition from a stationary to proliferative growth state. PMID- 9368017 TI - Role of 2,6-dideoxy-2,6-diaminoglucose in activation of a eukaryotic phospholipase C by aminoglycoside antibiotics. AB - Recent emergence of microbial resistance to aminoglycoside antibiotics, and the documented cytotoxicity associated with their use, calls for sustained efforts at understanding the effects of the compounds on eukaryotic cells. Using a glycosyl phosphatidylinositol (GPI)-phospholipase C (GPI-PLC) from the protozoan parasite Trypanosoma brucei, we demonstrate that a eukaryotic PLC can be activated 6-fold by aminoglycosides. Neomycin B protected GPI-PLC from a reduction in activity at pH 6.5, and increased the turnover number (kcat) of the enzyme. In structure activity studies with the neomycin group, 2-deoxy-streptamine was mildly stimulatory; the concentration required to activate GPI-PLC 2-fold (SC200) was 310 microM. Neamine was 150-fold more active (SC200 = 2 microM) than 2-deoxy streptamine, indicating that a 2,6-dideoxy-2, 6-diaminoglucose substituent at the 4-position of 2-deoxystreptamine plays an important role in activation of GPI PLC. Ribostamycin and neomycin B also had SC200's of 2 microM, implying that the ribose group in ribostamycin is not involved in activation of GPI-PLC. These conclusions were affirmed in studies with Bacillus thuringiensis phosphatidylinositol-specific phospholipase C. A 2, 6-dideoxy-2,6-diaminoglucose substitution at the 4-OH of 2-deoxystreptamine activates the enzyme 17-fold, while a second 2, 6-dideoxy-2,6-diaminoglucose moiety on the ribose ring of ribostamycin provides an additional 3.5-fold stimulation. Possible implications of these observations for the effects of aminoglycosides on eukaryote cells are discussed. PMID- 9368018 TI - Two novel brain-specific splice variants of the murine Cbeta gene of cAMP dependent protein kinase. AB - We have previously characterized two murine cAMP-dependent protein kinase catalytic subunit genes, Calpha and Cbeta1. Targeted disruption of the Cbeta1 promoter revealed two splice variants of the Cbeta catalytic subunit gene (designated Cbeta2 and Cbeta3) that continue to be expressed. These variants arise from unique promoters and are brain-specific. Cbeta2 is expressed in several discrete areas in the limbic system. These include the lateral septum, the bed nucleus of the stria terminalis, the ventral medial hypothalamus, and the amygdala. In the neocortex, expression is highest in cortical areas such as the prefrontal and insular cortex that are associated limbic structures. By contrast, Cbeta1 is most highly expressed in the cortex and hippocampus and is also present in all non-neuronal tissues examined. Cbeta3 is expressed at very low levels with wide distribution throughout the brain. Both the Cbeta2 and Cbeta3 variants are enzymatically active and induce gene expression in transient transfections with a cAMP response element-reporter construct. This activity is inhibited by protein kinase A regulatory subunits, the protein kinase inhibitor, and the chemical inhibitor H-89. We also demonstrate that Cbeta1 is myristoylated at the amino terminus like the Calpha isoform, but neither Cbeta2 nor Cbeta3 is myristoylated. The discrete expression of Cbeta variants in the brain suggests specific functional roles in neuronal signaling. PMID- 9368019 TI - Alanine insertion scanning mutagenesis of lactose permease transmembrane helices. AB - A priori, single residue insertions into transmembrane helices are expected to be highly disruptive to protein structure and function. We have carried out a systematic analysis of the phenotypes associated with Ala insertions into transmembrane helices in lactose permease, a multispanning Escherichia coli inner membrane protein. Insertion of alanine into the center of 7 transmembrane helices was found to abolish stable integration of lactose permease into the membrane or uphill lactose transport. A more detailed Ala insertion scan was made of transmembrane helix III. The results pin-point a central region of approximately 2 helical turns that is crucial for lactose permease stability and/or activity. A Trp scan in this region identified 2 residues essential for lactose permease stability. From these results, it appears that transmembrane helices have differential sensitivities to single residue insertions and that such mutations may be useful for identifying structurally and/or functionally important helix segments. PMID- 9368021 TI - Regulation of cross-linking of actin filament by IQGAP1, a target for Cdc42. AB - We have previously shown that IQGAP1, a recently identified target for Cdc42 and Rac1 small GTPases, showed a distribution similar to that of cortical actin cytoskeleton at the membrane ruffling area induced by insulin and Rac1(val12) (Kuroda, S., Fukata, M., Kobayashi, K., Nakafuku, M., Nomura, N., Iwamatsu, A., and Kaibuchi, K. (1996) J. Biol. Chem. 271, 23363-23367). Here we identified an IQGAP1-interacting molecule with molecular mass of 43 kDa (p43) from bovine brain cytosol, using glutathione S-transferase (GST)-IQGAP1 affinity column chromatography. The amino acid sequencing of the protein revealed that p43 was identical to beta- and gamma-actin. IQGAP1 was cosedimentated with filamentous actin (F-actin). The amino-terminal domain (amino acids 1-216) of IQGAP1 was responsible for the interaction with F-actin. Falling ball viscometry assay revealed that IQGAP1 cross-linked the F-actin. This IQGAP1 activity was further enhanced by guanosine 5'-(3-O-thio)triphosphate (GTPgammaS).GST-Cdc42 but not by GDP.GST-Cdc42. The gel filtration analysis of IQGAP1 revealed that IQGAP1 appeared as oligomers and that GTPgammaS.GST-Cdc42 but not GDP.GST-Cdc42 enhanced the oligomerization of IQGAP1. These results strongly suggest that IQGAP1, acting downstream of Cdc42, can cross-link the actin filament through its oligomerization. PMID- 9368020 TI - Solution structure of parathyroid hormone related protein (residues 1-34) containing an Ala substituted for an Ile in position 15 (PTHrP[Ala15]-(1-34)). AB - The structure of human parathyroid hormone (PTH) related protein (residues 1-34) containing an Ala substituted for an Ile in position 15 was studied by two dimensional proton nuclear magnetic resonance spectroscopy. This mutant retains quite high levels of adenylate cyclase activity based on slightly reduced PTH receptor binding capacity. Three segments of helix were revealed extending from His5 to Lys11, Lys13 to Arg19, and from Phe22 to Thr33/Ala34, with a decided kink between the first two helices around Gly12. N- and C-terminal helices were stabilized by charged and hydrophobic side chain interactions between His5 and Glu30, Asp17 and both His9 and His25, and between Leu8 and Ala29, resulting in a globular molecule occupying a single conformation. While the structure of the entire mid-molecule region differed greatly from the structure of the native peptide, the structure of both N- and C-terminal regions remains essentially unaltered. The residues responsible for initiating signal transduction in the mutant are located in the vicinity of the residues responsible for receptor binding. The C-terminal amphipathic helix forming the receptor binding site exhibits reduced binding as a result of the closely applied N-terminal signal transduction-activating region. Although not contributing directly to receptor binding, the N-terminal region can sterically affect hormone binding through modifications to certain N-terminal side chains. PMID- 9368022 TI - Identification and characterization of the functional amino acids at the active site of the large thioredoxin reductase from Plasmodium falciparum. AB - The thioredoxin system, composed of the pyridine nucleotide-disulfide oxidoreductase thioredoxin reductase, the small peptide thioredoxin, and NADPH as a reducing cofactor, is one of the major thiol-reducing systems of the cell. Recent studies revealed that Plasmodium falciparum and human thioredoxin reductase represent a novel class of enzymes, called large thioredoxin reductases. The large thioredoxin reductases are substantially different from the isofunctional prokaryotic Escherichia coli enzyme. The putative essential amino acids at the catalytic center of large thioredoxin reductase from P. falciparum were determined by using site-directed mutagenesis techniques. To analyze the putative active site cysteines (Cys88 and Cys93) three mutant proteins were constructed substituting alanine or serine residues for cysteine residues. Further, to evaluate the function of His509 as a putative proton donor/acceptor of large thioredoxin reductase this residue was replaced by either glutamine or alanine. All mutants were expressed in the E. coli system and characterized. Steady state kinetic analysis revealed that the replacement of Cys88 by either alanine or serine and Cys93 by alanine resulted in a total loss of enzymatic activity. These results clearly identify Cys88 and Cys93 as the active site thiols of large thioredoxin reductase. The replacement of His509 by glutamine yielded in a 95% loss of thioredoxin reductase activity; replacement by alanine provoked a loss of 97% of enzymatic activity. These results identify His509 as active site base, but imply that its function can be substituted, although inefficiently, by an alternative proton donor, similar to glutathione reductase. Spectral analysis of wild-type P. falciparum thioredoxin reductase revealed a 550 nm absorption band upon reduction which resembles the EH2 form of glutathione reductase and lipoamide dehydrogenase. This spectral feature, recently also reported for the human placenta protein (Arscott, L. D., Gromer, S., Schirmer, R. H., Becker K., and Williams, C. H., Jr. (1997) Proc. Natl. Acad. Sci. U. S. A. 94, 3621-3626), further illustrates the similarity between large thioredoxin reductases and glutathione reductases and stresses the profound differences to small E. coli thioredoxin reductase. PMID- 9368023 TI - Serpin-derived peptide substrates for investigating the substrate specificity of human tissue kallikreins hK1 and hK2. AB - The third human tissue kallikrein to be identified, hK2, could be an alternate or complementary marker to kallikrein hK3 (prostate-specific antigen) for prostate diseases. Most of the hK2 in seminal plasma forms an inactive complex with protein C inhibitor (PCI), a serpin secreted by seminal vesicles. As serpin inhibitors behave as suicide substrates that are cleaved early in the interaction with their target enzyme, and kallikreins have different sensitivities to serpin inhibitors, we prepared a series of substrates with intramolecularly quenched fluorescence based on the sequences of the serpin reactive loops. They were used to compare the substrate specificities of hK1 and hK2, which both have trypsin like specificity, and thus differ from chymotrypsin-like hK3. The serpin-derived peptides behaved as kallikrein substrates whose sensitivities reflected the specificity of the parent inhibitory proteins. Substrates derived from PCI were the most sensitive for both hK1 and hK2 with specificity constants of about 10(7) M-1. s-1. Those derived from antithrombin III and alpha2-antiplasmin were more specific for hK2 while a kallistatin-derived substrate was specifically cleaved by hK1. hK1 and hK2 substrates of greater specificity were obtained using chimeric peptides based on the sequence of serpin reactive loops. The main difference between specificities of hK1 and hK2 arise because hK2 can accommodate positively charged as well as small residues at P2 and requires an arginyl residue at P1. Thus, unlike hK1, hK2 does not cleave kininogen-derived substrates overlapping the region of N-terminal insertion of bradykinin in human kininogens. PMID- 9368024 TI - Severely impaired polymerization of recombinant fibrinogen gamma-364 Asp --> His, the substitution discovered in a heterozygous individual. AB - During blood coagulation, soluble fibrinogen is converted to fibrin monomers that polymerize to form an insoluble clot. Polymerization has been described as a two step process: the formation of double-stranded protofibrils and the subsequent lateral aggregation of protofibrils into fibers. Previous studies have shown that gamma chain residues Tyr-363 and Asp-364 have a significant role in polymerization, most likely in protofibril formation. To better define the role of these residues, we synthesized three fibrinogens with single substitutions at these two positions: Tyr-363 --> Ala, Asp-364 --> Ala, and Asp-364 --> His. We found that the release of fibrinopeptides A and B was the same for these variants and normal recombinant fibrinogen, showing that all variants had normal fibrin formation. In contrast, we found that polymerization was significantly delayed for both Ala variants and was almost nonexistent for the His variant. Clottability for the Ala variants was only slightly reduced, and fibrin gels were formed. Surprisingly, clottability of the His variant was substantially reduced, and fibrin gels were not formed. Our data suggest that both protofibril formation and lateral aggregation were altered by these substitutions, indicating that the C-terminal domain of the gamma chain has a role in both polymerization steps. PMID- 9368025 TI - Activating amphiphiles cause a conformational change of the 1,2-diacylglycerol 3 glucosyltransferase from Acholeplasma laidlawii membranes according to proteolytic digestion. AB - 1,2-Diacylglycerol 3-glucosyltransferase synthesizes the major nonbilayer-prone lipid monoglucosyldiacylglycerol (MGlcDAG) in the membrane of Acholeplasma laidlawii, which is important for the spontaneous curvature, and is a regulatory site for the lipid surface charge density. A potential connection between activity and a conformational change of this enzyme, governed by essential lipid activators, was studied with purified MGlcDAG synthase in different lipid aggregates. Critical fractions of anionic phospholipids 1, 2-dioleoyl phosphatidylglycerol (DOPG) and 1,2-dioleoyl-phosphatidylserine (DOPS) were essential for the restoration of enzyme activity, while the zwitterionic 1,2 dioleoyl-phosphatidylcholine (DOPC) and the uncharged diglucosyldiacylglycerol (DGlcDAG) were not. Proteolytic resistance had a very good correlation with the enzyme activity in various lipid-CHAPS mixed micelles. Anionic lipids DOPG and DOPS could protect the exposed MGlcDAG synthase from digestion, whereas DOPC and DGlcDAG could not. Similar features were observed in liposome bilayers. Likewise, the detergent dodecylphosphoglycerol (PGD), with a phosphatidylglycerol-like headgroup, could also stimulate the MGlcDAG synthase activity efficiently with a concomitant protection toward proteolytic digestion. Neither proteolytic resistance nor restored enzyme activity was observed using soluble glycerol 3 phosphate. It is concluded that in addition to critical amounts, both the negatively charged headgroup and hydrophobic chains of the activator amphiphiles, but not a certain aggregate curvature, seem necessary for a proper conformation and the resulting active state of the MGlcDAG synthase. PMID- 9368026 TI - Stimulus-selective inhibition of rat osteocalcin promoter induction and protein DNA interactions by the homeodomain repressor Msx2. AB - Osteocalcin (OC) is a matrix calcium-binding protein expressed in osteoblasts and odontoblasts undergoing mineralization. OC expression is up-regulated in part by signals initiated by basic fibroblast growth factor (FGF2), cyclic AMP or forskolin (FSK), and calcitriol via defined elements and DNA-protein interactions in the OC promoter. We identified the OC gene as a target for transcriptional suppression by Msx2, a homeodomain transcription factor that controls ossification in the developing skull. In this study, we examine the effects of Msx2 expression on OC promoter activation (luciferase reporter) by FGF2/FSK and calcitriol in MC3T3-E1 osteoblasts. Expression of Msx2 decreases basal activity of the 1-kilobase (-1050 to +32) rat OC promoter by 80%; however, the promoter is still inducible 3-fold by calcitriol. By contrast, OC promoter induction by FGF2/FSK is completely abrogated by Msx2. Because intrinsic Msx2 DNA binding activity is not required for the Msx2 suppressor function, we assessed whether Msx2 represses OC activation by regulating DNA-protein interactions at the FGF2 response element (OCFRE) and compared these interactions with those occurring at the calcitriol response element (VDRE). Treatment of MC3T3-E1 cells with FGF2/FSK or calcitriol up-regulates specific DNA-protein interactions at the OCFRE or VDRE, respectively, as detected by gel shift assay. Preincubation of crude nuclear extracts with recombinant glutathione S-transferase (GST)-Msx2 dose dependently inhibits OCFRE DNA binding activity, whereas GST has no effect. Msx2 itself does not bind the OCFRE. Residues 132-148 required for Msx2 core suppressor function in transfection assays are also required to inhibit OCFRE DNA binding activity. By contrast, GST-Msx2 has no effect on calcitriol-regulated DNA protein interactions at the VDRE. Using gel shift as an assay, the OCFRE DNA binding protein OCFREB was purified to about 50% homogeneity from MG63 osteosarcoma cells. Recombinant Msx2 inhibits purified OCFREB DNA binding activity, whereas the Msx2 variant lacking residues 132-148 is inactive. Thus, Msx2 abrogates up-regulation of the OC promoter by FGF2/FSK in part by inhibiting OCFREB binding to the OCFRE. PMID- 9368027 TI - Down-regulation of major histocompatibility complex Q1b gene expression by 2,3,7,8-tetrachlorodibenzo-p-dioxin. AB - We analyzed mouse hepatoma cells using differential display to discover new genes that respond to the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). We identified a class I major histocompatibility complex (MHC) gene, which we designated as MHC Q1b, whose expression decreases in the presence of TCDD. TCDD-induced down-regulation of MHC Q1b requires both the aromatic hydrocarbon receptor and the aromatic hydrocarbon receptor nuclear translocator, transcription factors that up-regulate other genes in response to TCDD. Down regulation of MHC Q1b by TCDD appears to involve both transcriptional and post transcriptional regulatory events; the post-transcriptional destabilization of MHC Q1b mRNA is probably a secondary response to TCDD. Our findings reveal new mechanistic aspects of gene regulation by TCDD. In addition, our observations suggest a mechanism that might account for some of TCDD's immunotoxic effects. PMID- 9368028 TI - Synthesis of mannose-(inositol-P)2-ceramide, the major sphingolipid in Saccharomyces cerevisiae, requires the IPT1 (YDR072c) gene. AB - Knowledge of the Saccharomyces cerevisiae genes and proteins necessary for sphingolipid biosynthesis is far from complete. Such information should expedite studies of pathway regulation and sphingolipid functions. Using the Aur1 protein sequence, recently identified as necessary for synthesis of the sphingolipid inositol-P-ceramide (IPC), we show that a homolog (open reading frame YDR072c), termed Ipt1 (inositolphosphotransferase 1) is necessary for synthesis of mannose (inositol-P)2-ceramide (M(IP)2C), the most abundant and complex sphingolipid in S. cerevisiae. This conclusion is based upon analysis of an ipt1-deletion strain, which fails to accumulate M(IP)2C and instead accumulates increased amounts of the precursor mannose-inositol-P-ceramide. The mutant also fails to incorporate radioactive precursors into M(IP)2C, and membranes prepared from it do not incorporate [3H-inositol]phosphatidylinositol into M(IP)2C, indicating a lack of M(IP)2C synthase activity (putatively phosphatidylinositol:mannose-inositol-P ceramide phosphoinositol transferase). M(IP)2C synthase activity is inhibited in the micromolar range by aureobasidin A, but drug sensitivity is over 1000-fold lower than reported for IPC synthase activity. An ipt1-deletion mutant has no severe phenotypic effects but is slightly more resistant to growth inhibition by calcium ions. Identification of the IPT1 gene should be helpful in determining the function of the M(IP)2C sphingolipid and in determining the catalytic mechanism of IPC and M(IP)2C synthases. PMID- 9368029 TI - Overexpression of 3'-untranslated region of the myotonic dystrophy kinase cDNA inhibits myoblast differentiation in vitro. AB - The genetic defect underlying myotonic dystrophy (DM) has been identified as an unstable CTG trinucleotide repeat amplification in the 3'-untranslated region (3' UTR) of the DM kinase gene (DMK). Individuals with the most severe congenital form display a marked delay in muscle terminal differentiation. To gain insight into the role of DMK during myogenesis, we have examined the effect of DMK overexpression on the terminal differentiation of the murine myoblast cell line C2C12. We demonstrate that a 4-10-fold constitutive overexpression of DMK mRNA in myoblasts caused a marked inhibition of terminal differentiation. Surprisingly, this activity was mapped to a 239-nucleotide region of the 3'-UTR of the DMK transcript. When the DMK 3'-UTR was placed downstream of a reporter gene, the same inhibition of myogenesis was observed. Following the induction of differentiation of myoblast clones overexpressing the DMK 3'-UTR, the levels of myogenin mRNA were reduced by approximately 4-fold, whereas the steady state levels of mef-2c transcripts were not affected. These data suggest that overexpression of the DMK 3'-UTR may interfere with the expression of musclespecific mRNAs leading to a delay in terminal differentiation. PMID- 9368030 TI - Creatine phosphate, not ATP, is required for 3' end cleavage of mammalian pre mRNA in vitro. AB - The poly(A) tail of a mammalian mRNA is generated by endonucleolytic cleavage and poly(A) addition. Previous studies conducted with nuclear extracts suggested an ATP requirement for the cleavage step. We have reexamined the cofactor requirement, initially with the SV40 late pre-mRNA, which requires for cleavage four protein factors, cleavage and polyadenylation specificity factor, cleavage stimulation factor, cleavage factor I, and cleavage factor II. Using highly purified preparations of these factors, which lacked detectable creatine phosphokinase and ATPase activities, creatine phosphate (CP) was, surprisingly, found to be sufficient to promote efficient cleavage. Although other phosphate compounds substituted poorly or not at all for CP, another phosphoguanidine, arginine phosphate, was fully functional. Notably, ATP was neither necessary nor sufficient, and could in fact inhibit the reaction. Treatment of the purified factors with hexokinase plus glucose (to deplete any contaminating ATP) was without effect, as was addition of EDTA. Using 32P-labeled CP, we found that neither hydrolysis of CP nor phosphate transfer from CP occurred during the cleavage reaction. CP also allowed cleavage of the adenovirus 2 L3 pre-mRNA. However, in this case, ATP both enhanced the reaction and influenced the precise site of cleavage, perhaps reflecting the requirement of poly(A) polymerase for cleavage of this RNA. These results indicate that ATP is not essential for 3' pre mRNA cleavage and that CP or a related compound can function as a necessary cofactor. PMID- 9368031 TI - Oxidation kinetics of ethanol by human cytochrome P450 2E1. Rate-limiting product release accounts for effects of isotopic hydrogen substitution and cytochrome b5 on steady-state kinetics. AB - A number of cytochrome P450 (P450) 2E1 substrates are known to show kinetic deuterium isotope effects of approximately 5 on Km (DK = DKm/HKm), but not on kcat, in rat liver microsomes (e.g. N-nitrosodimethylamine, ethanol, and CH2Cl2). We observed DKm values of 3-5 for recombinant human P450 2E1-catalyzed ethanol oxidation. Replacing NADPH and O2 with the oxygen surrogate cumene hydroperoxide yielded similar results. Ferric P450 2E1 reduction was fast (k >1000 min-1) even in the absence of substrate. These results indicate that the basis for the increase in Km is in the latter portion of the catalytic cycle. The intrinsic isotope effect (Dk) for ethanol oxidation was determined (competitively) to be 3.8, indicating that C-H bond cleavage is isotopically sensitive. Pre-steady state studies showed a burst of product formation (k = 410 min-1), with the burst amplitude corresponding to the P450 concentration. Deuteration of ethanol resulted in an isotope effect of 3.2 on the rate of the burst. We conclude that product release is rate-limiting in the oxidation of ethanol to acetaldehyde by P450 2E1. The steady-state kinetics can be described by a paradigm in which the kcat approximates the rate of product release, and Km is an expression in which the denominator is dominated by the rate of C-H bond breaking. PMID- 9368032 TI - Identification of four distinct pools of catenins in mammalian cells and transformation-dependent changes in catenin distributions among these pools. AB - Catenins are cytoplasmic proteins that were initially identified in a complex with cadherins, a superfamily of transmembrane glycoproteins important for cell adhesion in normal and disease states. We have used gel filtration to identify four complexes of catenins in extracts from normal and transformed epithelial cells. In normal Madin-Darby canine kidney epithelial cells, a significant fraction of alpha- and beta-catenin and plakoglobin co-elute with cadherin in a high molecular weight complex (complex I). A portion of alpha-catenin and the remainder of beta-catenin and plakoglobin co-elute in a high molecular weight complex that does not contain cadherin (complex II). The remainder of alpha catenin elutes in a low molecular weight fraction (complex III). In extracts from two colon carcinoma cell lines, HCT116 and SW480, beta-catenin elutes in an additional low molecular weight pool (complex IV) not present in Madin-Darby canine kidney cell extracts. In two subclones derived from SW480 cells, SW-E8 and SW-R2, beta-catenin is distributed evenly between high and low molecular weight pools in SW-E8 cells, whereas it elutes primarily in the low molecular weight pool (complex IV) in SW-R2 cells. These changes in beta-catenin elution profiles correlate with an increase in transformed phenotype and decreased cell-cell adhesion in the SW-R2 cells. PMID- 9368033 TI - Comparison of the Ca2+-binding properties of human recombinant calretinin-22k and calretinin. AB - Calretinin-22k (CR-22k) is a splice product of calretinin (CR) found specifically in cancer cells, and possesses four EF-hands and a differently processed C terminal end. The Ca2+-binding properties of recombinant human calretinin CR-22k were investigated by flow dialysis and spectroscopic methods and compared with those of CR. CR possesses four Ca2+-binding sites with positive cooperativity (nH = 1.3) and a [Ca2+]0.5 of 1.5 microM, plus one low affinity site with an intrinsic dissociation constant (K'D) of 0.5 mM. CR-22k contains three Ca2+ binding sites with nH of 1.3 and [Ca2+]0.5 of 1.2 microM, plus a low affinity site with K'D of 1 mM. All the sites seem to be of the Ca2+-specific type. Limited proteolysis and thiol reactivity suggest that that the C terminus of full length CR, but not of CR-22k, is in close proximity of site I leading to mutual shielding. Circular dichroism (CD) spectra predict that the content of alpha helix in CR and CR-22k is similar and that Ca2+ binding leads to very small changes in the CD spectra of both proteins. The optical properties are very similar for CR-22k and CR, even though CR-22k possesses one additional Trp at the C-terminal end, and revealed that the Trp residues are organized into a hydrophobic core in the metal-free proteins and become even better shielded from the aqueous environment upon binding of Ca2+. The fluorescence of the hydrophobic probe 2-p-toluidinylnaphtalene-6-sulfonate is markedly enhanced by the two proteins already in the absence of Ca2+ and is further increased by binding of Ca2+. The trypsinolysis patterns of CR and CR-22k are markedly dependent on the presence or absence of Ca2+. Together, our data suggest the presence of an allosteric conformational unit encompassing sites I-III for CR-22k and I-IV for CR, with a very similar conformation and conformational changes for both proteins. In the allosteric unit of CR, site IV is fully active, whereas in CR 22k this site has a 80-fold decreased affinity, due to the decreased amphiphilic properties of the C-terminal helix of this site. Some very specific Ca2+ dependent conformational changes suggest that both CR and CR-22k belong to the "sensor"-type family of Ca2+-binding proteins. PMID- 9368034 TI - Cloning and expression of a novel mammalian homolog of Drosophila transient receptor potential (Trp) involved in calcium entry secondary to activation of receptors coupled by the Gq class of G protein. AB - Hormonal stimulation of Gq-protein coupled receptors triggers Ca2+ mobilization from internal stores. This is followed by a Ca2+ entry through the plasma membrane. Drosophila Trp and Trpl proteins have been implicated in Ca2+ entry and three mammalian homologues of Drosophila Trp/Trpl, hTrp1, hTrp3 and bTrp4 (also bCCE) have been cloned and expressed. Using mouse brain RNA as template, we report here the polymerase chain reaction-based cloning and functional expression of a novel Trp, mTrp6. The cDNA encodes a protein of 930 amino acids, the sequence of which is 36.8, 36.3, 43.1, 38.6, and 74. 1% identical to Drosophila Trp and Trpl, bovine Trp4, and human Trp1 and Trp3, respectively. Transient expression of mTrp6 in COS.M6 cells by transfection of the full-length mTrp6 cDNA increases Ca2+ entry induced by stimulation of co-transfected M5 muscarinic acetylcholine receptor with carbachol (CCh), as seen by dual wavelength fura 2 fluorescence ratio measurements. The mTrp6-mediated increase in Ca2+ entry activity was blocked by SKF-96365 and La3+. Ca2+ entry activity induced by thapsigargin was similar in COS cells transfected with or without the mTrp6 cDNA. The thapsigargin-stimulated Ca2+ entry could not be further stimulated by CCh in control cells but was markedly increased in mTrp6-transfected cells. Records of whole cell transmembrane currents developed in response to voltage ramps from -80 to +40 mV in control HEK cells and HEK cells stably expressing mTrp6 revealed the presence of a muscarinic receptor responsive non-selective cation conductance in Trp6 cells that was absent in control cells. Our data support the hypothesis that mTrp6 encodes an ion channel subunit that mediates Ca2+ entry stimulated by a G protein coupled receptor, but not Ca2+ entry stimulated by intracellular Ca2+ store depletion. PMID- 9368036 TI - Interactions among subunits of the oligosaccharyltransferase complex. AB - The mammalian oligosaccharyltransferase (OST) is an oligomeric complex composed of three membrane proteins of the endoplasmic reticulum: ribophorin I (RI), ribophorin II (RII), and OST48. In addition, sequence homology between the Ost2 subunit of the yeast OST complex and Dad1 (defender against apoptotic death) suggests that Dad1 may represent a fourth subunit of the mammalian OST complex. In attempts to elucidate the structural organization of this complex, we have studied the interactions among its subunits. Using the yeast two-hybrid system, we have shown that the luminal domains of RI and RII (RIL and RIIL, respectively) interacted with the luminal domain of OST48 (OST48L), but no direct interaction was observed between RIL and RIIL. These results were confirmed by biochemical assays. Deletion analyses using the yeast two-hybrid system showed that subdomain of RIL or RIIL adjacent to the respective transmembrane domains interacted with OST48L. Of the three equal length subdomains of OST48L, the one at the N terminus and the one next to the transmembrane domain interacted with RIL. None of these three subdomains of OST48L interacted with RIIL. The yeast two-hybrid assay also revealed affinity between the cytoplasmically located N-terminal region of Dad1 and the short cytoplasmic tail of OST48, thus placing Dad1 firmly into the OST complex. In addition, we found a homotypic interaction between the cytoplasmic domains of RI, which may play a role in the formation of the oligomeric array formed by components of the translocation machinery. PMID- 9368035 TI - Catalytic mechanism and role of hydroxyl residues in the active site of theta class glutathione S-transferases. Investigation of Ser-9 and Tyr-113 in a glutathione S-transferase from the Australian sheep blowfly, Lucilia cuprina. AB - Spectroscopic and kinetic studies have been performed on the Australian sheep blowfly Lucilia cuprina glutathione S-transferase (Lucilia GST; EC 2.5.1.18) to clarify its catalytic mechanism. Steady state kinetics of Lucilia GST are non Michaelian, but the quite hyperbolic isothermic binding of GSH suggests that a steady state random sequential Bi Bi mechanism is consistent with the anomalous kinetics observed. The rate-limiting step of the reaction is a viscosity dependent physical event, and stopped-flow experiments indicate that product release is rate-limiting. Spectroscopic and kinetic data demonstrate that Lucilia GST is able to lower the pKa of the bound GSH from 9.0 to about 6.5. Based on crystallographic suggestions, the role of two hydroxyl residues, Ser-9 and Tyr 113, has been investigated. Removal of the hydroxyl group of Ser-9 by site directed mutagenesis raises the pKa of bound GSH to about 7.6, and a very low turnover number (about 0.5% of that of wild type) is observed. This inactivation may be explained by a strong contribution of the Ser-9 hydroxyl group to the productive binding of GSH and by an involvement in the stabilization of the ionized GSH. This serine residue is highly conserved in the Theta class GSTs, so the present findings may be applicable to all of the family members. Tyr-113 appears not to be essential for the GSH activation. Stopped-flow data indicate that removal of the hydroxyl group of Tyr-113 does not change the rate-limiting step of reaction but causes an increase of the rate constants of both the formation and release of the GSH conjugate. Tyr-113 resides on alpha-helix 4, and its hydroxyl group hydrogen bonds directly to the hydroxyl of Tyr-105. This would reduce the flexibility of a protein region that contributes to the electrophilic substrate binding site; segmental motion of alpha-helix 4 possibly modulates different aspects of the catalytic mechanism of the Lucilia GST. PMID- 9368037 TI - Identification of protein phosphatase 1 as a mitotic lamin phosphatase. AB - At the onset of mitosis, the nuclear lamins are hyperphosphorylated leading to nuclear lamina disassembly, a process required for nuclear envelope breakdown and entry into mitosis. Multiple lamin kinases have been identified, including protein kinase C, that mediate mitotic lamin phosphorylation and mitotic nuclear lamina disassembly. Conversely, lamin dephosphorylation is required for nuclear lamina reassembly at the completion of mitosis. However, the protein phosphatase(s) responsible for the removal of mitotic phosphates from the lamins is unknown. In this study, we use human lamin B phosphorylated at mitosis specific sites as a substrate to identify and characterize a lamin phosphatase activity from mitotic human cells. Several lines of evidence demonstrate that the mitotic lamin phosphatase corresponds to type 1 protein phosphatase (PP1). First, mitotic lamin phosphatase activity is inhibited by high nanomolar concentrations of okadaic acid and the specific PP1 peptide inhibitor, inhibitor-2. Second, mitotic lamin phosphatase activity cofractionates with PP1 after ion exchange chromatography. Third, microcystin-agarose depletes mitotic extracts of both PP1 and lamin phosphatase activity. Our results demonstrate that PP1 is the major mitotic lamin phosphatase responsible for removal of mitotic phosphates from lamin B, a process required for nuclear lamina reassembly. PMID- 9368038 TI - The regulation of glycogen synthase by protein phosphatase 1 in 3T3-L1 adipocytes. Evidence for a potential role for DARPP-32 in insulin action. AB - The stimulation of glycogen-targeted protein phosphatase 1 (PP1), glycogen synthase, and glycogen synthesis by insulin was examined during the differentiation of 3T3-L1 fibroblasts into adipocytes. Insulin treatment barely changed the low levels of glycogen synthesis measured in fibroblasts. Following differentiation into adipocytes, insulin increased glycogen synthesis up to 40 fold. After further culturing of the adipocytes for a week, insulin stimulated glycogen accumulation 700-fold. Differentiation of 3T3-L1 cells also resulted in the increased expression of glycogen synthase and in increases in both total glycogen synthase activity and -fold stimulation by insulin. While the levels of PP1 protein were unchanged by differentiation, PP1 specific activity decreased over 60%, although sensitivity to insulin treatment was augmented. Concurrently, levels of the PP1 inhibitor protein DARPP-32 were dramatically induced upon 3T3 L1 adipogenesis. DARPP-32 in both 3T3-L1 and primary rat adipocytes was exclusively localized to the particulate fractions, including the glycogen enriched pellet. PP1 activity from 3T3-L1 adipocytes exhibited a kinetic lag in vitro, which was not present in fibroblast extracts. Insulin pretreatment of the adipocyte cells overcame the in vitro lag in PP1 activity, resulting in up to 5 fold stimulation of PP1 activity being measured at early assay time points. These results suggest that in 3T3-L1 adipocytes, DARPP-32 may maintain glycogen targeted PP1 activity in a low basal state, priming the phosphatase for stimulation by insulin. PMID- 9368039 TI - Hydroxylation of Saccharomyces cerevisiae ceramides requires Sur2p and Scs7p. AB - The Saccharomyces cerevisiae SCS7 and SUR2 genes are members of a gene family that encodes enzymes that desaturate or hydroxylate lipids. Sur2p is required for the hydroxylation of C-4 of the sphingoid moiety of ceramide, and Scs7p is required for the hydroxylation of the very long chain fatty acid. Neither SCS7 nor SUR2 are essential for growth, and lack of the Scs7p- or Sur2p-dependent hydroxylation does not prevent the synthesis of mannosyldiinositolphosphorylceramide, the mature sphingolipid found in yeast. Deletion of either gene suppresses the Ca2+-sensitive phenotype of csg2Delta mutants, which arises from overaccumulation of inositolphosphorylceramide due to a defect in sphingolipid mannosylation. Characterization of scs7 and sur2 mutants is expected to provide insight into the function of ceramide hydroxylation. PMID- 9368040 TI - Effects of reagent and enzymatically generated hypochlorite on physicochemical and metabolic properties of high density lipoproteins. AB - Myeloperoxidase (MPO), a protein secreted by activated phagocytes, may be a potential candidate for the generation of modified/oxidized lipoproteins in vivo via intermediate formation of HOCl, a powerful oxidant. During the present study, the effects of reagent NaOCl and OCl- generated by the MPO/H2O2/Cl- system on physicochemical and metabolic properties of high density lipoprotein (HDL) subclass 3 (HDL3) were investigated. Up to a molar oxidant:lipoprotein ratio of approximately 30:1, apolipoprotein A-I (apoA-I), the major HDL3 apolipoprotein component, represented the preferential target for OCl- attack (consuming 35-76% of the oxidant), thereby protecting HDL3 fatty acids (consuming between 17 and 30% of the oxidant) against OCl--mediated modification. At molar oxidant:HDL3 ratios >/= 60:1, we have observed pronounced consumption of HDL3 unsaturated fatty acids with concomitant formation of fatty acid chlorohydrins. Modification of HDL3 in the presence of the MPO/H2O2/Cl- system resulted in amino acid oxidation in a manner comparable with that found with reagent NaOCl only. Treatment of HDL3 with reagent NaOCl as well as modification by the MPO/H2O2/Cl- system resulted in significantly enhanced turnover rates of HDL3 by mouse peritoneal macrophages, an effect that was not a result of HDL3 aggregation as judged by dynamic and static light-scattering experiments. In comparison with native HDL3, the degradation by macrophages was enhanced by 4- and 15-fold when HDL3 was modified with reagent NaOCl or the MPO/H2O2/Cl- system. Finally, the ability of HDL3 to promote cellular cholesterol efflux from macrophages was significantly diminished after modification with reagent NaOCl. Collectively, these results demonstrate that the modification of HDL3 by hypochlorite (added as reagent or generated by the MPO/H2O2/Cl- system) transformed an antiatherogenic lipoprotein particle into a modified lipoprotein with characteristics similar to lipoproteins commonly thought to initiate foam cell formation in vivo. PMID- 9368041 TI - Evolution of fucosyltransferase genes in vertebrates. AB - Cloning and expression of chimpanzee FUT3, FUT5, and FUT6 genes confirmed the hypothesis that the gene duplications at the origin of the present human cluster of genes occurred between: (i) the great mammalian radiation 80 million years ago and (ii) the separation of man and chimpanzee 10 million years ago. The phylogeny of fucosyltransferase genes was completed by the addition of the FUT8 family of alpha(1,6)fucosyltransferase genes, which are the oldest genes of the fucosyltransferase family. By analysis of data banks, a new FUT8 alternative splice expressed in human retina was identified, which allowed mapping the human FUT8 gene to 14q23. The results suggest that the fucosyltransferase genes have evolved by successive duplications, followed by translocations, and divergent evolution from a single ancestral gene. PMID- 9368042 TI - Notch-1 controls the expression of fatty acid-activated transcription factors and is required for adipogenesis. AB - Notch, a transmembrane receptor member of the homeotic epidermal growth factor like family of proteins, participates in cell-to-cell signaling to control cell fate during development. Activated Notch-1 constructs lacking the extracellular region prevent differentiation of several mammalian cells in vitro. This effect, however, bypasses the normal mechanisms of cell-to-cell interactions in which Notch-1 participates. We investigated the role of Notch-1 in the hormone-induced adipocyte differentiation of 3T3-L1 fibroblasts, a paradigmatic model of adipogenesis that requires cell-to-cell contact. Unlike other differentiation models, Notch-1 expression and function were necessary conditions for adipogenesis. Impaired Notch-1 expression by antisense Notch-1 constructs prevented adipocyte differentiation. Strategies aimed at blocking putative Notch/ligand interactions also blocked adipogenesis, implicating Notch as a critical molecule in cell-to-cell signaling necessary for differentiation. Inhibition of Notch-1 expression or function decreased the expression of peroxisomal proliferator-activated receptors delta and gamma, transcription factors that control adipocyte differentiation and that are up-regulated at cell confluence. These results implicate Notch in the commitment of 3T3-L1 cells to undergo adipogenesis by controlling the expression of the principal regulators of this process. PMID- 9368043 TI - Identification of a ligand-binding site on the granulocyte colony-stimulating factor receptor by molecular modeling and mutagenesis. AB - Granulocyte colony-stimulating factor (G-CSF) initiates its effects on cells of the neutrophil lineage by inducing formation of a homodimeric receptor complex. The structure of the G-CSF receptor has not yet been determined, therefore we used molecular modeling to identify regions of the receptor that were likely to be involved in ligand binding. The G-CSF receptor sequence was aligned with all the available sequences of the gp130 and growth hormone receptor families and a model of the cytokine receptor homologous domain was constructed, based on the growth hormone receptor structure. Alanine substitution mutagenesis was performed on loops and individual residues that were predicted to bind ligand. Mutant receptors were expressed in factor-dependent Ba/F3 cells and assessed for proliferation response and ligand binding. Six residues were identified that significantly reduced receptor function, with Arg288 in the F'-G' loop having the greatest effect. These residues formed a binding face on the receptor model resembling the growth hormone receptor site, which suggests that the model is reasonable. However, electrostatic analysis of the model provided further evidence that the mechanism of receptor dimerization is different from that of the growth hormone receptor. PMID- 9368044 TI - Molecular cloning and cell cycle-dependent expression of mammalian CRM1, a protein involved in nuclear export of proteins. AB - Crm1 of Schizosaccharomyces pombe, a nuclear protein essential for proliferation and chromosome region maintenance, is a possible target of leptomycin B, an antifungal and antitumor antibiotic with cell cycle-arresting activity. cDNA encoding a human homolog of Crm1 was cloned. Human CRM1 (hCRM1) consisted of 1071 amino acids, of which the sequence showed 52% homology with S. pombe Crm1. hCRM1 weakly complemented the cold-sensitive mutation of S. pombe crm1-809, as did S. pombe crm1+. Overproduction of hCRM1 under the control of a series of nmt1 promoters suppressed cell proliferation in wild-type S. pombe in an expression level-dependent manner. A similar inhibitory effect was also observed for crm1+. Cells overproducing either hCRM1 or S. pombe Crm1 were distinctly larger than uninduced cells and contained compacted and fragmented nuclei. Furthermore, calcofluor staining demonstrated that most of these cells formed two septa per cell and accumulated a large amount of chitin or its related polysaccharides around the septa. Closely similar phenotypes between hCRM1- and S. pombe Crm1 induced cells indicate that the cloned cDNA encodes a functional homolog of S. pombe crm1+. Northern blot analyses with RNAs isolated from synchronized mammalian cells showed that the expression of mammalian CRM1 was initiated in late G1 and reached a peak at G2/M, although its protein level unchanged during the cell cycle. Transient expression of hCRM1 fused to the green fluorescent protein (GFP) in NIH3T3 cells showed that hCRM1 was localized preferentially in the nuclear envelope and was also detectable in the nucleoplasm and the cytoplasm. A crm1 mutation of S. pombe caused nuclear import of a GFP fusion protein containing a nuclear export signal but no change in the distribution of a GFP fusion protein containing a nuclear localization signal. All of these data suggest that CRM1 is a novel cell-cycle regulated gene that is essential for the nuclear export signal-dependent nuclear export of proteins. PMID- 9368045 TI - Human apolipoprotein B transgenic mice generated with 207- and 145-kilobase pair bacterial artificial chromosomes. Evidence that a distant 5'-element confers appropriate transgene expression in the intestine. AB - We reported previously that approximately 80-kilobase pair (kb) P1 bacteriophage clones spanning either the human or mouse apoB gene (clones p158 and p649, respectively) confer apoB expression in the liver of transgenic mice, but not in the intestine. We hypothesized that the absence of intestinal expression was due to the fact that these clones lacked a distant DNA element controlling intestinal expression. To test this possibility, transgenic mice were generated with 145- and 207-kb bacterial artificial chromosomes (BACs) that contained the human apoB gene and more extensive 5'- and 3'-flanking sequences. RNase protection, in situ hybridization, immunohistochemical, and genetic complementation studies revealed that the BAC transgenic mice manifested appropriate apoB gene expression in both the intestine and the liver, indicating that both BACs contained the distant intestinal element. To determine whether the regulatory element was located 5' or 3' to the apoB gene, transgenic mice were generated by co-microinjecting embryos with p158 and either the 5'- or 3'-sequences from the 145-kb BAC. Analysis of these mice indicated that the apoB gene's intestinal element is located 5' to the structural gene. Cumulatively, the transgenic mouse studies suggest that the intestinal element is located between -33 and -70 kb 5' to the apoB gene. PMID- 9368046 TI - The tetramerization region of the retinoid X receptor is important for transcriptional activation by the receptor. AB - The retinoid X receptor (RXR), a member of the superfamily of hormone nuclear receptors, is a ligand-inducible transcription factor that is activated by the vitamin A derivative 9-cis-retinoic acid. We previously showed that RXR self associates into tetramers with a high affinity and that ligand binding induces rapid dissociation of receptor tetramers to smaller species. Here, the RXR region that is responsible for mediating tetramer formation is identified. It is shown that this interface, which we term the "tetramerization domain," critically contains two consecutive phenylalanine residues located at the C-terminal region of the receptor. Mutation of these residues is sufficient to disrupt RXR tetramers without affecting the overall fold of the protein or interfering with ligand binding, dimer formation, or DNA binding by the receptor. Nevertheless, the tetramer-impaired mutant was found to be transcriptionally defective. The newly characterized tetramerization domain and the previously identified main dimerization interface of RXR act autonomously to affect separate intersubunit interactions that, overall, lead to formation of tetramers. Protein-protein interactions mediated by the tetramerization domain, but not those that involve the dimerization interface, are disrupted following ligand binding by RXR. Overall, these data attest to the specificity of the interaction and implicate the tetramerization interface in playing a direct role in regulating transcriptional activation by RXR. PMID- 9368047 TI - An autoinhibitory control element defines calcium-regulated isoforms of nitric oxide synthase. AB - Nitric oxide synthases (NOSs) are classified functionally, based on whether calmodulin binding is Ca2+-dependent (cNOS) or Ca2+-independent (iNOS). This key dichotomy has not been defined at the molecular level. Here we show that cNOS isoforms contain a unique polypeptide insert in their FMN binding domains which is not shared with iNOS or other related flavoproteins. Previously identified autoinhibitory domains in calmodulin-regulated enzymes raise the possibility that the polypeptide insert is the autoinhibitory domain of cNOSs. Consistent with this possibility, three-dimensional molecular modeling suggested that the insert originates from a site immediately adjacent to the calmodulin binding sequence. Synthetic peptides derived from the 45-amino acid insert of endothelial NOS were found to potently inhibit binding of calmodulin and activation of cNOS isoforms. This inhibition was associated with peptide binding to NOS, rather than free calmodulin, and inhibition could be reversed by increasing calmodulin concentration. In contrast, insert-derived peptides did not interfere with the arginine site of cNOS, as assessed from [3H]NG-nitro-L-arginine binding, nor did they potently effect iNOS activity. Limited proteolysis studies showed that calmodulin's ability to gate electron flow through cNOSs is associated with displacement of the insert polypeptide; this is the first specific calmodulin induced change in NOS conformation to be identified. Together, our findings strongly suggest that the insert is an autoinhibitory control element, docking with a site on cNOSs which impedes calmodulin binding and enzymatic activation. The autoinhibitory control element molecularly defines cNOSs and offers a unique target for developing novel NOS activators and inhibitors. PMID- 9368048 TI - A modulatory subunit of acid sensing ion channels in brain and dorsal root ganglion cells. AB - MDEG1 is a cation channel expressed in brain that belongs to the degenerin/epithelial Na+ channel superfamily. It is activated by the same mutations which cause neurodegeneration in Caenorhabditis elegans if present in the degenerins DEG-1, MEC-4, and MEC-10. MDEG1 shares 67% sequence identity with the recently cloned proton-gated cation channel ASIC (acid sensing ion channel), a new member of the family which is present in brain and in sensory neurons. We have now identified MDEG1 as a proton-gated channel with properties different from those of ASIC. MDEG1 requires more acidic pH values for activation and has slower inactivation kinetics. In addition, we have cloned from mouse and rat brain a splice variant form of the MDEG1 channel which differs in the first 236 amino acids, including the first transmembrane region. This new membrane protein, which has been called MDEG2, is expressed in both brain and sensory neurons. MDEG2 is activated neither by mutations that bring neurodegeneration once introduced in C. elegans degenerins nor by low pH. However, it can associate both with MDEG1 and another recently cloned H+-activated channel DRASIC to form heteropolymers which display different kinetics, pH dependences, and ion selectivities. Of particular interest is the subunit combination specific for sensory neurons, MDEG2/DRASIC. In response to a drop in pH, it gives rise to a biphasic current with a sustained current which discriminates poorly between Na+ and K+, like the native H+-gated current recorded in dorsal root ganglion cells. This sustained current is thought to be required for the tonic sensation of pain caused by acids. PMID- 9368049 TI - A single chain Fv fragment of P-glycoprotein-specific monoclonal antibody C219. Design, expression, and crystal structure at 2.4 A resolution. AB - A construct encoding a single chain variable fragment of the anti-P-glycoprotein monoclonal antibody C219 was made by combining the coding sequences for the heavy and light chain variable domains with a sequence encoding the flexible linker (GGGGS)3, an OmpA signal sequence, a c-myc identification tag, and a five histidine purification tag. The construct was expressed in Escherichia coli and purified from the periplasmic fraction using a nickel chelate column and ion exchange chromatography. Three-step Western blot analysis showed that the construct retains binding affinity for P-glycoprotein. Crystals of 1.0 x 0.2 x 0.2 mm were grown in 100 mM citrate, pH 4.5, 21% polyethylene glycol 6000 in the presence of low concentrations of subtilisin, resulting in proteolytic removal of the linker and purification tags. The structure was solved to a resolution of 2.4 A with an R factor of 20.6, an Rfree of 28.5, and good stereochemistry. This result could lead to a clinically useful product based on antibody C219 for the diagnosis of P-glycoprotein-mediated multidrug resistance. The molecule will also be useful in biophysical studies of functional domains of P-glycoprotein, as well as studies of the intact molecule. PMID- 9368050 TI - The Beige/Chediak-Higashi syndrome gene encodes a widely expressed cytosolic protein. AB - The human autosomal recessive disorder Chediak-Higashi syndrome and its murine homologue beige are associated with the formation of giant lysosomes that cluster near the perinuclear region of cells. We prepared a polyclonal antiserum against a glutathione S-transferase-Beige fusion protein and demonstrated by Western analysis that the beige gene encodes a protein of 400 kDa that is expressed in cultured murine fibroblasts as well as most mouse tissues. The protein was not detected in either cultured fibroblasts or mouse tissues from two different beige mutants. Cultured fibroblasts transformed with multiple copies of yeast artificial chromosomes that contain the full-length beige gene showed much higher levels of Beige protein than either wild type fibroblasts or mouse tissues. Subcellular fractionation experiments demonstrated that the Beige protein was cytosolic and, under the conditions of isolation, had no measurable membrane association. Cultured mouse fibroblasts in which the Beige protein was overexpressed had smaller than normal lysosomes that were more peripherally distributed than in control cells. These findings, coupled with earlier published results, suggest that the Beige protein regulates lysosomal fission. PMID- 9368051 TI - Transcriptional repression by zinc finger peptides. Exploring the potential for applications in gene therapy. AB - A series of studies were performed to determine whether zinc finger peptides could efficiently repress transcription from RNA polymerase II promoters in vivo and to determine how such repression might depend on the position of the zinc finger binding site with respect to those of the TATA box or the initiator element. Promoter constructs were prepared with Zif268 binding sites inserted at various positions, and the activity of a reporter gene was measured in transfection studies. We found that the peptide containing the three zinc fingers of Zif268 could efficiently repress activated transcription when bound to a site near the TATA box (19-fold repression) or when bound to a site near the initiator element (18-fold repression). Repression was even more effective when the zinc finger peptide was bound to both of these sites (63-fold repression). Novel zinc finger peptides that had been selected via phage display also served as repressors of activated transcription, but repression with these proteins was somewhat less efficient than with the Zif268 peptide. PMID- 9368052 TI - Identification of a novel transcriptional regulatory element common to the p53 and interferon regulatory factor 1 genes. AB - The promoter regions of both the interferon regulatory factor (IRF1) and p53 antioncogenes contain a previously unidentified sequence denoted IRF1 p53 common sequence (IPCS), which markedly increases the transcriptional activity of a reporter gene placed under the control of an heterologous promoter in transfected U937 cells. In contrast, transfection of U937 cells with reporter vectors containing p53 and IRF1 promoters with mutated IPCS sites resulted in a 4-fold reduction in the constitutive expression of those two genes. The transcriptional activity of IPCS is strictly correlated with the binding of a novel nuclear factor, IPCS-binding factor (IPCS-BF). IPCS-BF, which is composed of a single polypeptide of 26 kDa, is present constitutively in nuclear extracts of both U937 cells and peripheral blood mononuclear cells from healthy donors. The finding that the pattern of binding of IPCS-BF to the IPCS is unlike that of any known transcription factor and that the IPCS sequence does not exhibit any significant homology with any known binding site present in the data base, strongly suggest that IPCS-BF is a novel transcription factor which, by virtue of this ability to regulate the expression of the p53 and IRF1 genes, could play a central role in the control of cell proliferation and/or apoptosis. PMID- 9368053 TI - Regulation of phagosomal acidification. Differential targeting of Na+/H+ exchangers, Na+/K+-ATPases, and vacuolar-type H+-atpases. AB - Vacuolar-type (V) ATPases are thought to be the main determinant of phagosomal acidification. In phagosomes containing mycobacteria, which ostensibly impair the delivery of V-ATPases to the phagosomal membrane, the pH would be expected to be near neutral. This prediction was tested by microfluorescence ratio imaging using macrophages from mice susceptible to mycobacterial infection. Although less acidic than their counterparts containing dead bacteria, phagosomes containing live Mycobacteria bovis were nearly 1 pH unit more acidic than the cytosol, suggesting the existence of alternate H+ transport mechanisms. We therefore investigated whether Na+/H+ exchange (NHE) contributes to phagosomal acidification. Immunoblotting, reverse transcriptase-polymerase chain reaction, and pharmacological studies indicated that NHE1 is the predominant isoform of the exchanger in macrophages. Fractionation revealed that NHE1 is incorporated into the phagosomal membrane, and measurements of pH indicated that it is functional in this location. Nevertheless, acidification of the lumen of phagosomes containing either latex beads or live M. bovis was insensitive to (3 methylsulfonyl-4-piperidinobenzoyl)-guanidine methanesulfonate, a potent inhibitor of NHE1. This may have been due to the absence of an appropriate lumen to cytosol Na+ gradient, because the phagosomal membrane was found to be devoid of Na+/K+ pumps. Unexpectedly, the acidification of M. bovis phagosomes was fully reversed by specific inhibitors of the vacuolar H+-ATPase, suggesting that ATPases are present only transiently or in reduced quantities in the phagosomal membrane. Alternatively, acid equivalents accumulated in endosomes by V-ATPases may be delivered to the mycobacterial phagosome by carrier vesicles devoid of ATPases. PMID- 9368054 TI - Interaction between the amino- and carboxyl-terminal regions of the rat androgen receptor modulates transcriptional activity and is influenced by nuclear receptor coactivators. AB - Identical N-terminal deletions in the wild-type rat androgen receptor (rAR) and a constitutively active rAR (ARDelta641-902) devoid of the ligand-binding domain (LBD) resulted in dissimilar consequences in transcriptional activation: deletion of residues 149-295 abolished wild-type AR activity, but did not influence that of ARDelta641-902. The activity of the N-terminal transactivation domain is thus controlled by the hormone-occupied LBD, suggesting that the N- and C-terminal regions of rAR communicate. Consistent with this idea, a strong androgen dependent interaction between the N-terminal region and LBD was demonstrated in a mammalian two-hybrid system using GAL4 and VP16 fusion proteins. This interaction can be direct or indirect. Several nuclear receptor coactivators (CBP, F-SRC-1, SRC-1, and RIP140) that interact with other steroid receptors were tested as potential mediators of the N- and C-terminal interaction of rAR using the mammalian two-hybrid system. CBP or F-SRC-1 not only enhanced AR-mediated transactivation, but also facilitated the androgen-dependent interaction between the N- and C-terminal domains, implying that part of the coactivator-dependent transcriptional activation occurs via this mechanism. In contrast, SRC-1, a coactivator for the progesterone receptor, inhibited both AR-mediated transactivation and interaction between the N and C termini. Recruitment of coregulators may involve AR domains other than the LBD, as F-SRC-1 and CBP enhanced, but SRC-1 repressed, the transcriptional activity of ARDelta641-902. Collectively, interplay between the N-terminal region and LBD of rAR results in the formation of a transactivation complex that includes coregulators and that is mandatory for optimal activation of androgen-induced promoters. PMID- 9368055 TI - Insulin receptor substrate-2 (IRS-2) can mediate the action of insulin to stimulate translocation of GLUT4 to the cell surface in rat adipose cells. AB - Insulin receptor substrates-1 and -2 (IRS-1 and -2) are important substrates of the insulin receptor tyrosine kinase. Previous studies have focused upon the role of IRS-1 in mediating the actions of insulin. In the present study, we demonstrate that IRS-2 can mediate translocation of the insulin responsive glucose transporter GLUT4 in a physiologically relevant target cell for insulin action. Co-immunoprecipitation experiments performed on cell lysates derived from freshly isolated rat adipose cells incubated in the presence or absence of insulin indicated that twice as much phosphatidylinositol 3-kinase was associated with endogenous IRS-1 as with IRS-2 after insulin stimulation. When rat adipose cells in primary culture were transfected with expression vectors for IRS-1 or IRS-2, we observed 40-fold overexpression of human IRS-1 or murine IRS-2. In addition, anti-phosphotyrosine immunoblotting experiments confirmed that the recombinant substrates were phosphorylated in response to insulin stimulation. To examine the role of IRS-2 in insulin-stimulated translocation of GLUT4, we studied the effects of overexpression of IRS-1 and -2 on translocation of a co transfected epitope-tagged GLUT4 (GLUT4-HA). Overexpression of IRS-1 or IRS-2 in adipose cells resulted in a significant increase in the basal level of cell surface GLUT4 (in the absence of insulin). Interestingly, at maximally effective concentrations of insulin (60 nM), the level of cell surface GLUT4 in cells overexpressing IRS-1 or -2 significantly exceeded the maximal recruitment observed in the control cells (160 and 135% of control, respectively; p < 0.003). Our data directly demonstrate that IRS-2, like IRS-1, is capable of participating in insulin signal transduction pathways leading to the recruitment of GLUT4. Thus, IRS-2 may provide an alternative pathway for critical metabolic actions of insulin. PMID- 9368056 TI - Isolation and characterization of a novel ligand-dependent thyroid hormone receptor-coactivating protein. AB - The thyroid hormone receptor (TR) regulates the expression of target genes upon binding to triiodothyronine (T3) response elements. In the presence of T3, the TR recruits coactivating proteins that both modulate and integrate the ligand response. We report here the cloning of a novel protein using the TR ligand binding domain as bait in the yeast two-hybrid system. Analysis of a putative full-length clone demonstrates a cDNA sequence that encodes a protein of 920 amino acids with a size of 120 kDa (p120). Alignment with known sequences shows homology to a previously identified protein of unknown function, termed skeletal muscle abundant protein. Interaction studies demonstrate that p120 interacts with the TR AF-2 domain in the presence of ligand through a 111-amino acid region. Northern analysis demonstrates widespread expression in human tissues. Cotransfection assays in CV-1 cells demonstrate that p120 enhances TR-mediated transactivation on multiple T3 response elements in the presence of T3. In addition, CREB-binding protein synergizes with p120 to enhance this effect. When linked to the GAL4 DNA-binding domain, p120 is an activator of transcription alone. Thus, p120 satisfies a number of important criteria as a nuclear receptor coactivator. PMID- 9368057 TI - Interaction of CArG elements and a GC-rich repressor element in transcriptional regulation of the smooth muscle myosin heavy chain gene in vascular smooth muscle cells. AB - We have previously shown that maximal expression of the rat smooth muscle myosin heavy chain (SM-MHC) gene in cultured rat aortic smooth muscle cells (SMCs) required the presence of a highly conserved domain (nucleotides -1321 and -1095) that contained two positive-acting serum response factor (SRF) binding elements (CArG boxes 1 and 2) and a negative-acting GC-rich element that was recognized by Sp1 (Madsen, C. S., Hershey, J. C., Hautmann, M. B., White, S. L., and Owens, G. K. (1997) J. Biol. Chem. 272, 6332-6340). In this study, to better understand the functional role of these three cis elements, we created a series of SM-MHC reporter-gene constructs in which each element was mutated either alone or in combination with each other and tested them for activity in transient transfection assays using primary cultured rat aortic SMCs. Results demonstrated that the most proximal SRF binding element (CArG-box1) was active in the absence of CArG-box2, but only upon removal of the GC-rich repressor. In contrast, regardless of sequence context, CArG-box2 was active only when CArG-box1 was present. We further demonstrated using electrophoretic mobility shift assays that Sp1 binding to the GC-rich repressor element did not prevent SRF binding to the adjacent CArG-box2. Thus, unlike other proteins reported to inhibit SRF activity, the repressor activity associated with the GC-rich element does not appear to function through direct inhibition of SRF binding. As a first step toward understanding the importance of these elements in vivo, we performed in vivo footprinting on the intact rat aorta. We demonstrated that both CArG boxes and the GC-rich element were bound by protein within the animal. Additionally, using the rat carotid injury model we showed that Sp1 protein was significantly increased in SMCs located within the myointimal lesion, suggesting that increased expression of this putative repressor factor may contribute to the decreased SM MHC expression within SMCs found in myointimal lesions. PMID- 9368058 TI - The cyclin-dependent kinase-activating kinase (CAK) assembly factor, MAT1, targets and enhances CAK activity on the POU domains of octamer transcription factors. AB - Octamer binding transcription factors (Oct factors) play important roles in activation of transcription of various genes but, in some cases, require cofactors that interact with the DNA binding (POU) domain. In the present study, a yeast two-hybrid screen with the Oct-1 POU domain as a bait identified MAT1 as a POU domain-binding protein. MAT1 is known to be required for the assembly of cyclin-dependent kinase (CDK)-activating kinase (CAK), which is functionally associated with the general transcription factor IIH (TFIIH). Further analyses showed that MAT1 interacts with POU domains of Oct-1, Oct-2, and Oct-3 in vitro in a DNA-independent manner. MAT1-containing TFIIH was also shown to interact with POU domains of Oct-1 and Oct-2. MAT1 is shown to enhance the ability of a recombinant CDK7-cyclin H complex (bipartite CAK) to phosphorylate isolated POU domains, intact Oct-1, and the C-terminal domain of RNA polymerase II, but not the originally defined substrate, CDK2. Phosphopeptide mapping indicates that the site (Ser385) of a mitosis-specific phosphorylation that inhibits Oct-1 binding to DNA is not phosphorylated by CAK. However, one CAK-phosphorylated phosphopeptide comigrates with a Cdc2-phosphorylated phosphopeptide previously shown to be mitosis-specific, suggesting that, in vitro, CAK is able to phosphorylate at least one site that is also phosphorylated in vivo. These results suggest (i) that interactions between POU domains and MAT1 can target CAK to Oct factors and result in their phosphorylation, (ii) that MAT1 not only functions as a CAK assembly factor but also acts to alter the spectrum of CAK substrates, and (iii) that a POU-MAT1 interaction may play a role in the recruitment of TFIIH to the preinitiation complex or in subsequent initiation and elongation reactions. PMID- 9368059 TI - The conversion from the dehydrogenase type to the oxidase type of rat liver xanthine dehydrogenase by modification of cysteine residues with fluorodinitrobenzene. AB - When rat liver xanthine dehydrogenase was incubated with fluorodinitrobenzene (FDNB) at pH 8.5, the total enzyme activity decreased gradually to a limited value of initial activity with modification of two lysine residues in a similar way to the modification of bovine milk xanthine oxidase with FDNB (Nishino, T., Tsushima, K., Hille, R. and Massey, V. (1982) J. Biol. Chem. 257, 7348-7353). After modification with FDNB, the two peptides containing dinitrophenyl-lysine were isolated from the molybdopterin domain after proteolytic digestion and were identified as Lys754 and Lys771 by sequencing the peptides. During the modification of these lysine residues, xanthine dehydrogenase was found to be converted to an oxidase form in the early stage of incubation. Incorporation of the 3H-dinitrophenyl group into enzyme cysteine residues was 0.96 mol per enzyme FAD for 68% conversion to the oxidase form. The modified enzyme was reconverted to the dehydrogenase form by incubation with dithiothreitol with concomitant release of 3H-dinitrophenyl compounds. After modification with 3H-FDNB followed by carboxymethylation under denaturating conditions, the enzyme was digested with proteases. Three 3H-dinitrophenyl-labeled peptides were isolated and sequenced. The modified residues were identified to be Cys535, Cys992 and Cys1324. These residues are conserved among the all known mammalian enzymes, but Cys992 and Cys1324 are not conserved in the chicken enzyme. Cys1324 of the rat enzyme was found not to be involved in the conversion from the dehydrogenase to the oxidase by limited proteolysis experiments, but Cys535 and Cys992 which seemed to be modified alternatively with FDNB appear to be involved in the conversion. PMID- 9368060 TI - Identification of a novel suppressive vitamin D response sequence in the 5' flanking region of the murine Id1 gene. AB - Vitamin D promotes differentiation of cells either by simply enhancing phenotypic gene expression and/or by suppressing expression of inhibitors of differentiation. Previously, we reported that expression of a gene encoding Id1, a negative type helix-loop-helix transcription factor, was transcriptionally suppressed by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) (1). To identify the sequence required for the negative regulation by 1, 25(OH)2D3, a 1.5-kilobase 5' flanking region of murine Id1 gene was examined by transiently transfecting luciferase reporter constructs into ROS17/2.8 osteoblastic cells. The transcriptional activity of this construct was repressed by 10(-8) M 1,25(OH)2D3. Deletion analysis revealed that a 57-base pair (bp) upstream response sequence (URS) (-1146/-1090) was required for the suppression by 1,25(OH)2D3. This sequence conferred negative responsiveness to 1,25(OH)2D3 to a heterologous SV40 promoter. The 57-bp URS contained not only Egr-1 consensus sequence (2) but also four direct repeats of a heptamer sequence (C/A)CAGCCC. Electrophoresis mobility shift assay revealed that the 57-bp URS formed specific nuclear protein-DNA complexes, which were neither competed by previously known positive and negative vitamin D response elements nor supershifted by anti-vitamin D receptor antibody, suggesting the absence of vitamin D receptor in these complexes. These results indicate the involvement of the novel 57-bp sequence in the vitamin D suppression of Id1 gene transcription. PMID- 9368061 TI - Studies on the mechanism of DNA linking by Epstein-Barr virus nuclear antigen 1. AB - Epstein-Barr virus nuclear antigen 1 (EBNA1) can both bind to and link DNA. Dimers of EBNA1 bind specific sites, two clusters of which, the FR and DS, comprise the necessary cis-acting elements of the Epstein-Barr viral origin of plasmid replication. EBNA1-dimers can link FR and DS, looping out the intervening DNA. EBNA1 can also intermolecularly link DNAs to which it binds. Residues of EBNA1 that can mediate linking have been mapped to at least three, non overlapping domains. These domains, when fused to the dimerization and DNA binding domain of GAL4, can self-associate and thereby link DNAs bound site specifically by GAL4. Two disparate mechanisms could underlie self-association of linking domains: 1) linking domains could associate with other linking domains directly, or 2) linking domains could associate indirectly by binding to a common nucleic acid intermediate. We have found that EBNA1 can link DNA by each of these mechanisms, however, the linking domains associate directly with a greater apparent affinity than through a nonspecific nucleic acid intermediate. PMID- 9368062 TI - Overexpression of a single helix-loop-helix-type transcription factor, scleraxis, enhances aggrecan gene expression in osteoblastic osteosarcoma ROS17/2.8 cells. AB - Cell differentiation is determined by a certain set of transcription factors such as MyoD in myogenesis. However, transcription factors that play a positive role in phenotypic gene expression in skeletal cells are largely unknown, except the recently identified CBFA1. Scleraxis is a helix-loop-helix-type transcription factor whose transcripts are expressed in sclerotome and in a certain set of skeletal cells; however, nothing is known about its function with regard to the regulation of cell function. To examine possible roles of scleraxis, we overexpressed scleraxis in osteoblastic ROS17/2.8 cells, which express low levels of scleraxis. Scleraxis overexpression enhanced expression of the aggrecan gene, which is not normally expressed at high levels in these osteoblastic cells. Overexpression of scleraxis also increased mRNA levels of type II collagen and osteopontin while suppressing expression of osteoblast phenotype-related genes encoding type I collagen and alkaline phosphatase. Transient transfection experiments indicated that scleraxis enhanced the chloramphenicol acetyltransferase activity of the reporter construct AgCAT-8, which contained an 8-kilobase pair (kb) fragment of the aggrecan gene including both the promoter and its first intron. Deletion analysis identified a 1-kb region that is responsive to scleraxis within the aggrecan gene. This region contains two adjacent E-box sequences. A 29-base pair DNA fragment (AgE) containing these E box sequences bound to proteins in the ROS17/2.8 cell nuclear extracts as well as to in vitro translated scleraxis. This binding was competed with unlabeled AgE, but not with a mutated E-box DNA sequence (mAgE), indicating the specificity of the binding activity. The AgE binding activity in the ROS17/2.8 cell nuclear extracts was enhanced in the cells overexpressing scleraxis and was supershifted by the antiserum raised against scleraxis. Furthermore, AgE, but not mAgE, conferred responsiveness to scleraxis overexpression to a heterologous promoter. Finally, replacement mutation of the AgE sequence within the 2.5-kb AgCAT-1 construct significantly reduced its responsiveness to scleraxis. These results indicate that overexpression of a single helix-loop-helix-type transcription factor, scleraxis, enhances aggrecan gene expression via binding to the E-box containing AgE sequence in ROS17/2.8 cells. PMID- 9368063 TI - Unmasking a growth-promoting effect of the adrenocorticotropic hormone in Y1 mouse adrenocortical tumor cells. AB - The adrenocorticotropic hormone (ACTH) inhibits the growth of Y1 mouse adrenocortical tumor cells as well as normal adrenocortical cells in culture but stimulates adrenocortical cell growth in vivo. In this study, we investigated this paradoxical effect of ACTH on cell proliferation in Y1 adrenal cells and have unmasked a growth-promoting effect of the hormone. Y1 cells were arrested in the G1 phase of the cell cycle by serum starvation and monitored for progression through S phase by measuring [3H]thymidine incorporation into DNA and by measuring the number of nuclei labeled with bromodeoxyuridine. Y1 cells were stimulated to progress through S phase and to divide after a brief pulse of ACTH (up to 2 h). This effect of ACTH appeared to be cAMP independent, since ACTH also induced cell cycle progression in Kin-8, a Y1 mutant with defective cAMP dependent protein kinase activity. The growth-promoting effect of ACTH in Y1 was preceded by the rapid activation of p44 and p42 mitogen-activated protein kinases and by the accumulation of c-FOS protein. In contrast, continuous treatment with ACTH (14 h) inhibited cell cycle progression in Y1 cells by a cAMP-dependent pathway. The inhibitory effect of ACTH mapped to the midpoint of G1. Together, the results demonstrate a dual effect of ACTH on cell cycle progress, a cAMP independent growth-promoting effect early in G1 possibly mediated by mitogen activated protein kinase and c-FOS, and a cAMP-dependent inhibitory effect at mid G1. It is suggested that the growth-inhibitory effect of ACTH at mid-G1 represents an ACTH-regulated check point that limits cell cycle progression. PMID- 9368064 TI - Growth factors stimulate tyrosine dephosphorylation of p75 and its dissociation from the SH2 domain of Grb2. AB - The growth factor receptor-binding protein (Grb2) has a key role in initiating the mitogen-activated protein kinase signaling cascade in major cell regulatory pathways. The binding of proteins to the SH2 domain of Grb2 has been reported to occur mainly after they are tyrosine-phosphorylated following receptor activation. Using an in vitro binding assay, immunoprecipitation, and Far Western techniques, we report that in quiescent cells a 75-kDa protein binds directly to the SH2 domain of Grb2. All of the tyrosine-phosphorylated p75 protein co localizes with Grb2.Sos complex in the cytosolic fraction of the cell in vivo and undergoes tyrosine dephosphorylation when cells are treated with mitogenic ligands such as epidermal, platelet-derived, and fibroblast growth factors, endothelin-1, and bombesin but not tumor necrosis factor-alpha, interferon-alpha and -gamma, interleukein-6, and leukemic inhibitory factor, which are either cell growth inhibitory or not significantly mitogenic. The dephosphorylation of p75 and the ensuing dissociation from Grb2 is rapid, occurring within 30 s following mitogenic stimulation by ligands such as epidermal growth factor, suggesting p75 to be an early component in the signal transduction pathways involving Grb2. PMID- 9368065 TI - Specificities of cell permeant peptidyl inhibitors for the proteinase activities of mu-calpain and the 20 S proteasome. AB - Cell-permeant peptidyl aldehydes and diazomethylketones are frequently utilized as inhibitors of regulatory intracellular proteases. In the present study the specificities of several peptidyl inhibitors for purified human mu-calpain and 20 S proteasome were investigated. Acetyl-LLnL aldehyde, acetyl-LLM aldehyde, carbobenzyloxy-LLnV aldehyde (ZLLnVal), and carbobenzyloxy-LLY-diazomethyl ketone produced half-maximum inhibition of the caseinolytic activity of mu-calpain at concentrations of 1-5 x 10(-7) M. In contrast, only ZLLnVal was a reasonably potent inhibitor of the caseinolytic activity of 20 S proteasome, producing 50% inhibition at 10(-5) M. The other inhibitors were at least 10-fold less potent, producing substantial inhibition only at near saturating concentrations in the assay buffer. Further studies with ZLLnVal demonstrated that its inhibition of the proteasome was independent of casein concentration over a 25-fold range. Proteolysis of calpastatin or lysozyme by the proteasome was half-maximally inhibited by 4 and 22 microM ZLLnVal, respectively. Thus, while other studies have shown that ZLLnVal is a potent inhibitor of the hydrophobic peptidase activity of the proteasome, it appears to be a much weaker inhibitor of its proteinase activity. The ability of the cell permeant peptidyl inhibitors to inhibit growth of the yeast Saccharomyces cerevisiae was studied because this organism expresses proteasome but not calpains. Concentrations of ZLLnVal as high as 200 microM had no detectable effect on growth rates of overnight cultures. However, yeast cell lysates prepared from these cultures contained 2 microM ZLLnVal, an amount which should have been sufficient to fully inhibit hydrophobic peptidase activity of yeast proteasome. Degradation of ubiquitinylated proteins in yeast extracts by endogenous proteasome was likewise sensitive only to high concentrations of ZLLnVal. The higher sensitivity of the proteinase activity of calpains to inhibition by the cell permeant inhibitors suggests that calpain-like activities may be targets of these inhibitors in animal cells. PMID- 9368066 TI - High mobility group I proteins interfere with the homeodomains binding to DNA. AB - Homeodomains (HDs) constitute the DNA binding domain of several transcription factors that control cell differentiation and development in a wide variety of organisms. Most HDs recognize sequences that contain a 5'-TAAT-3' core motif. However, the DNA binding specificity of HD-containing proteins does not solely determine their biological effects, and other molecular mechanisms should be responsible for their ultimate functional activity. Interference by other factors in the HD/DNA interaction could be one of the processes by which HD-containing proteins achieve the functional complexity required for their effects on the expression of target genes. Using gel-retardation assay, we demonstrate that two members of the high mobility group I (HMGI) family of nuclear proteins (HMGI-C and HMGY) can bind to a subset of HD target sequences and inhibit HDs from binding to the same sequences. The inhibition of the HD/DNA interaction occurs while incubating HMGI-C with DNA either before or after the addition of the HD. The reduced half-life of the HD.DNA complex in the presence of HMGI-C, and the shift observed in the CD spectra recorded upon HMGI-C binding to DNA, strongly suggest that structural modifications of the DNA are responsible for the inhibition of the HD.DNA complex formation. Moreover, by co-transfection experiments we provide evidence that this inhibition can occur also in vivo. The data reported here would suggest that HMGI proteins may be potential regulators of the function of HD-containing proteins and that they are able to interfere with the access of the HD to their target genes. PMID- 9368068 TI - Functional properties of the separate subunits of human DNA helicase II/Ku autoantigen. AB - The Ku antigen consists of two subunits of 70 and 83 kDa and is endowed with both duplex DNA end-binding capacity and helicase activity (human DNA helicase II). HeLa Ku can be isolated from in vitro cultured human cells uniquely as a heterodimer, and the subunits can be separated by electrophoresis only under denaturing conditions. To dissect the molecular functions of the two subunits of the heterodimer, we have cloned and expressed their cDNAs separately in Escherichia coli. The two activities of Ku (DNA binding and unwinding) were reconstituted by mixing and refolding both subunits in equimolar amounts (Tuteja, N., Tuteja, R., Ochem, A., Taneja, P., Huang, N-W., Simoncsits, A., Susic, S., Rahman, K., Marusic, L., Chen, J., Zang, J., Wang, S., Pongor, S., and Falaschi, A. (1994) EMBO J. 13, 4991-5001). Renaturation of the separate subunits can be achieved in the presence of a synthetic solubilizing and stabilizing agent, dimethyl ethylammonium propane sulfonate (NDSB 195). The helicase activity of the Ku protein resides uniquely in the 70-kDa subunit, whereas the DNA end-binding activity can be reconstituted only through renaturation of the two subunits in the heterodimeric form and is practically absent in the separate subunits. The 83 kDa subunit, when refolded in the absence of the 70-kDa subunit, forms homodimers unable to unwind DNA and bind duplex ends. The three separate species (heterodimer, 70-kDa subunit, and 83-kDa subunit homodimer) all have ssDNA dependent ATPase activity. PMID- 9368067 TI - A molecular basis for insulin resistance. Elevated serine/threonine phosphorylation of IRS-1 and IRS-2 inhibits their binding to the juxtamembrane region of the insulin receptor and impairs their ability to undergo insulin induced tyrosine phosphorylation. AB - Tumor necrosis factor alpha (TNFalpha) or chronic hyperinsulinemia that induce insulin resistance trigger increased Ser/Thr phosphorylation of the insulin receptor (IR) and of its major insulin receptor substrates, IRS-1 and IRS-2. To unravel the molecular basis for this uncoupling in insulin signaling, we undertook to study the interaction of Ser/Thr-phosphorylated IRS-1 and IRS-2 with the insulin receptor. We could demonstrate that, similar to IRS-1, IRS-2 also interacts with the juxtamembrane (JM) domain (amino acids 943-984) but not with the carboxyl-terminal region (amino acids 1245-1331) of IR expressed in bacteria as His6 fusion peptides. Moreover, incubation of rat hepatoma Fao cells with TNFalpha, bacterial sphingomyelinase, or other Ser(P)/Thr(P)-elevating agents reduced insulin-induced Tyr phosphorylation of IRS-1 and IRS-2, markedly elevated their Ser(P)/Thr(P) levels, and significantly reduced their ability to interact with the JM region of IR. Withdrawal of TNFalpha for periods as short as 30 min reversed its inhibitory effects on IR-IRS interactions. Similar inhibitory effects were obtained when Fao cells were subjected to prolonged (20-60 min) pretreatment with insulin. Incubation of the cell extracts with alkaline phosphatase reversed the inhibitory effects of insulin. These findings suggest that insulin resistance is associated with enhanced Ser/Thr phosphorylation of IRS-1 and IRS-2, which impairs their interaction with the JM region of IR. Such impaired interactions abolish the ability of IRS-1 and IRS-2 to undergo insulin induced Tyr phosphorylation and further propagate the insulin receptor signal. Moreover, the reversibility of the TNFalpha effects and the ability to mimic its action by exogenously added sphingomyelinase argue against the involvement of a proteolytic cascade in mediating the acute inhibitory effects of TNFalpha on insulin action. PMID- 9368069 TI - Discrimination of amino acids mediating Ras binding from noninteracting residues affecting raf activation by double mutant analysis. AB - The contribution of residues outside the Ras binding domain of Raf (RafRBD) to Ras-Raf interaction and Ras-dependent Raf activation has remained unresolved. Here, we utilize a double mutant approach to identify complementary interacting amino acids that are involved in Ras-Raf interaction and activation. Biochemical analysis demonstrates that Raf-Arg59 and Raf-Arg67 from RafRBD are interacting residues complementary to Ras-Glu37 located in the Ras effector region. Raf-Arg59 and Raf-Arg67 also mediate interaction with Ras-Glu37 in Ras-dependent Raf activation. The characteristics observed here can be used as criteria for a role of residues from other regions of Raf in Ras-Raf interaction and activation. We developed a quantitative two-hybrid system as a tool to investigate the effect of point mutations on protein-protein interactions that elude biochemical analysis of bacterially expressed proteins. This assay shows that Raf-Ser257 in the RafCR2 domain does not contribute to Ras-Raf interaction and that the Raf-S257L mutation does not restore Raf binding to Ras-E37G. Yet, Raf-S257L displays high constitutive kinase activity and further activation by Ras-G12V/E37G is still impaired as compared with activation by Ras-G12V. This strongly suggests that the RafCR2 domain is an independent domain involved in the control of Raf activity and a common mechanism for constitutively activating mutants may be the interference with the inactive ground state of the kinase. PMID- 9368070 TI - Phosphorylation of alphaB-crystallin in response to various types of stress. AB - Phosphorylation of alphaB-crystallin, a member of the hsp27 family, in human glioma (U373 MG) cells was stimulated by exposure of the cells to various stimuli, which included heat, arsenite, phorbol 12-myristate 13-acetate (PMA), okadaic acid, H2O2, anisomycin, and high concentrations of NaCl or sorbitol, but not in response to agents that elevated intracellular levels of cyclic AMP. Cells exposed to PMA together with okadaic acid yielded three bands of 32P-labeled alphaB-crystallin when immunoprecipitated samples were subjected to electrophoresis on an isoelectric focusing gel. All of the phosphorylated residues were identified as serine, an indication that three different serine residues can act as sites of phosphorylation in alphaB-crystallin. Structural analysis by mass spectrometry revealed that phosphorylation of alphaB-crystallin occurred at serines 19, 45, and 59. Dithiothreitol and staurosporine selectively inhibited the phosphorylation induced by arsenite and the phorbol ester, respectively. SB202190, an inhibitor of p38 mitogen-activated protein (MAP) kinase, suppressed the phosphorylation induced by arsenite, anisomycin, H2O2, sorbitol, NaCl, and heat shock, but not that induced by PMA and okadaic acid. The PMA-induced phosphorylation was selectively suppressed by an inhibitor of p44 MAP kinase kinase, PD98059. Although PMA and arsenite preferentially stimulated the phosphorylation of Ser-45 and Ser-59, respectively, as determined with antibodies that recognized the respective phosphorylated forms of alphaB-crystallin, all three sites were phosphorylated in response to each stimulus. These results suggest that p38 MAP kinase or p44 MAP kinase might be involved in the signal transduction cascade that leads to the phosphorylation of alphaB-crystallin. The phosphorylation of alphaB-crystallin was also enhanced in the heart and diaphragm when rats were exposed to heat stress (42 degrees C for 20 min). PMID- 9368071 TI - Expression cloning of a cDNA encoding a sulfotransferase involved in the biosynthesis of the HNK-1 carbohydrate epitope. AB - The HNK-1 carbohydrate epitope is expressed on several neural adhesion glycoproteins and as a glycolipid, and is involved in cell interactions. The structural element of the epitope common to glycoproteins and glycolipids has been determined to be sulfate-3-GlcAbeta1--> 3Galbeta1-->4GlcNAc. The glucuronyltransferase and sulfotransferase are considered to be the key enzymes in the biosynthesis of this epitope because the rest of the structure occurs often in glycoconjugates. Here we describe the isolation of the rat sulfotransferase cDNA via an expression cloning strategy. The clone finally isolated predicts a protein of 356 amino acids, with characteristics of a type II transmembrane protein and with no sequence similarity to other known sulfotransferases. Both the enzyme expressed as a soluble fusion protein and homogenates of cells transfected with the full-length cDNA could transfer sulfate from a sulfate donor to acceptor substrates containing terminal glucuronic acid. PMID- 9368072 TI - Association of Src family tyrosine kinase Lyn with ganglioside GD3 in rat brain. Possible regulation of Lyn by glycosphingolipid in caveolae-like domains. AB - Association of gangliosides with specific proteins in the central nervous system was examined by co-immunoprecipitation with anti-ganglioside antibody. Protein kinase activity was detected in precipitates with monoclonal antibody to ganglioside GD3 (R24) from membranal fraction of rat brain. Using in vitro kinase assay, several phosphorylated proteins of 40, 53, 56, and 80 kDa were isolated by gel electrophoresis. Of these proteins, the proteins of 53 and 56 kDa (p53/56) were identified as two isoforms of Src family tyrosine kinase Lyn, based on co migration during gel electrophoresis, comparative peptide mapping, and sequential immunoprecipitation with anti-Lyn antibody. The identification was confirmed using a cDNA expression system in Chinese hamster ovary (CHO) cells, which express solely ganglioside GM3, the enzymatic substrate of GD3 synthase. In co transfection with GD3 synthase and Lyn expression plasmids, R24 immunoprecipitated Lyn and anti-Lyn antibody immunoprecipitated GD3. R24 treatment of rat primary cerebellar cultures induced Lyn activation and rapid tyrosine phosphorylation of several substrates including mitogen-activated protein kinases. Furthermore, sucrose density gradient analysis showed that Lyn of cerebellum and CHO transfectants were detected in a low density light scattering band, i.e. the caveolae membrane fraction. R24 immunoprecipitated caveolin from Triton X-100 extract of CHO transfectants. These observations suggest that GD3 may regulate Lyn in a caveolae-like domain on brain cell membranes. PMID- 9368073 TI - Characterization of the reovirus lambda1 protein RNA 5'-triphosphatase activity. AB - Characterization of the phosphohydrolytic activities of recombinant reovirus lambda1 protein demonstrates that, in addition to the previously reported nucleoside triphosphate phosphohydrolase and helicase activities, the protein also possesses RNA 5'-triphosphatase activity. This activity was absolutely dependent on the presence of a divalent cation, Mg2+ or Mn2+, and specifically removes the 5'-gamma-phosphate at the end of triphosphate-terminated RNAs. Kinetic competition analysis showed that nucleoside triphosphate phosphohydrolase and RNA 5'-triphosphatase reactions are carried out at a common active site. These results strongly support the idea that, in addition to its role as an RNA helicase during transcription of the viral genome, lambda1 also participates during formation of the cap structure at the 5' end of newly synthesized reovirus mRNAs. The lambda1 protein represents only the third RNA triphosphatase whose primary structure is known and the first described in a double-stranded RNA virus. PMID- 9368074 TI - Tissue-specific regulation of G-protein-coupled inwardly rectifying K+ channel expression by muscarinic receptor activation in ovo. AB - We investigated the effects of muscarinic acetylcholine receptor stimulation on the expression levels of the G-protein-coupled inwardly rectifying K+ channel (GIRK) subunits using solution hybridization and immunoblot analyses. We report here that treatment of chick embryos in ovo with muscarinic agonist causes decreases in mRNA levels encoding GIRK1 and GIRK4 in atria but does not alter GIRK1 expression in ventricles. In addition, GIRK1 protein levels also demonstrate a decrease in atria upon muscarinic acetylcholine receptor stimulation. Numerous receptors couple to the activation of the GIRK family of inwardly rectifying K+ channels; thus, these decreases represent a novel mechanism for regulating physiological responses to chronic agonist exposure. PMID- 9368075 TI - Functional cooperation and stoichiometry of protein translocases of the outer and inner membranes of mitochondria. AB - The qualitative relationship between preprotein translocases in the mitochondrial outer and inner membranes was determined by both a functional analysis and a determination of characteristic components of the translocases. Translocation contact sites of isolated mitochondria were saturated with intermediates of a matrix-targeted precursor of the beta-subunit of the F1-ATPase (pF1beta), and import of preproteins into the different mitochondrial subcompartments was monitored. A strong inhibition (75-95%) was observed for preproteins with an N terminal matrix targeting signal, indicating that a significant portion of the contact sites was blocked by accumulated F1beta. Insertion of preproteins into the outer membrane and import into the intermembrane space of preproteins without matrix targeting signals was inhibited by about 45%, indicating that functional outer membrane translocases were available despite saturation of contact sites. Similarly, import of members of the mitochondrial carrier family into the inner membrane was only partly inhibited (40-50%), demonstrating that functional Tim22 translocases were available to cooperate with the Tom machinery in the import of carrier proteins. The stoichiometry of Tom40, Tim23, and Tim22 in mitochondria was determined to be 5:1:0.22. We conclude that translocases of the outer membrane are present in excess over translocases of the inner membrane. PMID- 9368078 TI - Earl Philip Benditt PMID- 9368077 TI - Kinetic analysis of the binding of human matrix metalloproteinase-2 and -9 to tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. AB - The dissociation constants (Kd) of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 for the active and latent forms of matrix metalloproteinase (MMP)-2 and MMP-9 were evaluated using surface plasmon resonance (SPR) and enzyme inhibition studies. SPR analysis shows biphasic kinetics with high (nM) and low (microM) affinity binding sites of TIMP-2 and TIMP-1 for MMP-2 (72- and 62-kDa species) and MMP-9 (92- and 82-kDa species), respectively. In contrast, binding data of TIMP-2 to an MMP-2 45-kDa active form lacking the C-terminal domain and to an MMP-2 C-terminal domain (CTD) fragment displays monophasic kinetics with Kd values of 315 and 60 nM, respectively. This suggests that the CTD contains the high affinity binding site, whereas the catalytic domain contains the low affinity site. Also, binding of TIMP-2 to pro-MMP-2 is stronger at both the high and low affinity sites than the corresponding binding of TIMP-2 to the MMP-2 62 kDa form demonstrating the importance of the N-terminal prodomain. In addition, the Kd value of TIMP-1 for the MMP-2 62-kDa species is 28. 6 nM at the high affinity site, yet neither the MMP-2 45-kDa species nor the CTD interacts with TIMP-1. Enzyme inhibition studies demonstrate that TIMPs are slow binding inhibitors with monophasic inhibition kinetics. This suggests that a single binding event results in enzyme inhibition. The kinetic parameters for the onset of inhibition are fast (kon approximately 10(5) M-1 s-1) with slow off rates (koff approximately 10(-3) s-1). The inhibition constants (Ki) are in the 10(-7) 10(-9) M range and correlate with the values determined by SPR. PMID- 9368076 TI - The cyclin-dependent kinase inhibitor p21cip1 mediates the growth inhibitory effect of phorbol esters in human venous endothelial cells. AB - Long-term application of the phorbol ester phorbol 12,13-dibutyrate (PDBu) inhibits the proliferation of human venous endothelial cells. The cyclin dependent kinase inhibitor p21cip1 is a potential candidate mediating the PDBu induced delayed entry of the cells into S-phase (by approximately 10 h when compared with cells stimulated with basic fibroblast growth factor (bFGF)). Levels of p21cip1 (protein and mRNA) rapidly rise (within approximately 2 h) in endothelial cells treated with the active isomer beta-PDBu, but not with alpha PDBu; this effect is blocked by the mitogen-activated protein kinase kinase-1 (Mek1) inhibitor PD098059 and by the protein kinase C (PKC) antagonists GF109203X and rottlerin (selective for PKC-delta), but not Go 6976 (selective for Ca2+ dependent PKC isoforms). Rapamycin blocks the PDBu-induced accumulation of p21cip1 (but not of the cognate mRNA), indicating an action of PKC on p21(cip1) mRNA translation. If endothelial cells are recruited into the cell cycle by bFGF, p21cip1 mRNA and protein levels rise initially (within 2 h) and decline subsequently such that p21cip1 drops to a minimum prior to the initiation of DNA synthesis (i.e. after approximately 12 h). In bFGF-stimulated cells, changes in p21cip1 mRNA and protein are strictly linked. In contrast, the levels of p21cip1 mRNA decline substantially (>10 h) before the protein decreases in PDBu stimulated cells. Thus, PKC (presumably PKC-delta) regulates the amounts of p21cip1 in endothelial cells at the level of mRNA accumulation and translation, leading to a rapid and robust induction; following persistent PKC activation, p21(cip1) remains elevated despite reduced mRNA levels, indicating an enhanced stability of the protein. The bFGF-mediated increase in p21cip1 is blocked by the Mek1 inhibitor, but not by GF109203X; hence, in endothelial cells, induction of p21cip1 by PKC- and growth factor-dependent signaling is achieved by distinct pathways that converge and require activation of the mitogen-activated protein kinase cascade. The beta-PDBu-induced delayed S-phase entry and drop in p21cip1 are reversed if GF109203X is added 4 h after beta-PDBu to prevent persistent PKC activation. These observations indicate a cause and effect relation between sustained p21cip1 elevations and the delay in S-phase entry induced by beta-PDBu. PMID- 9368079 TI - Kazuo Ogawa PMID- 9368080 TI - Detection of Pneumocystis carinii by DNA amplification in human immunodeficiency virus-positive patients. AB - The opportunistic pathogen Pneumocystis carinii (PC) is a frequent cause of a life-threatening pneumonia in human immunodeficiency virus (HIV)-infected individuals and in other immunocompromised hosts. Specimens obtained from 128 bronchoalveolar lavage (BAL) fluid samples from 123 HIV-positive patients with pulmonary disease and undergoing a diagnostic bronchoscopy were evaluated to detect this organism. We have developed a rapid DNA extraction procedure for nested polymerase chain reaction (PCR) using two sets of primers (pAZ102-E, pAZ102-H and P1 = 5'-CTAGGATATAGCTGGTTTTC-3' and P2 = 5'-TCGACTATCTAGCTTATCGC 3'). The results were compared using cytological techniques (direct wet mount, Giemsa, toluidine blue O) and related to the clinical follow-up of patients. The nested PCR had a 91% sensitivity and a 93% specificity. The effect of chemoprophylaxis and the evaluation of the follow-up of patients are discussed. Nested PCR may represent an important additional tool, along with current cytological methods, for the detection of P. carinii; however, at present it cannot replace routine microbiological methods more simple and less expensive. PMID- 9368081 TI - An electrophoretic molecular karyotype of a clinical isolate of Aspergillus fumigatus and localization of the MDR-like genes AfuMDR1 and AfuMDR2. AB - The molecular karyotype of a clinical isolate of Aspergillus fumigatus (10AF/86/10) was determined by contour-clamped homogeneous electric field gel electrophoresis. Five chromosomal bands were resolved by this method. The resolved chromosomes ranged in size from 1.7 to 4.8 Mb, and together constituted a total genomic size of at least 15.8 Mb. Southern analysis of the separated chromosomes located the position of two MDR-like genes, AfuMDR1 and AfuMDR2, on chromosomes III and IV, respectively. The methods described herein may enable the application of molecular karyotyping of A. fumigatus in epidemiologic surveillance studies. PMID- 9368082 TI - Comparison of quantitative polymerase chain reaction, acid fast bacilli smear, and culture results in patients receiving therapy for pulmonary tuberculosis. AB - Quantitative-competitive polymerase chain reaction (QPCR) was performed on serial sputum samples from 22 consecutive cases of acid fast bacilli (AFB) smear positive pulmonary tuberculosis. Of 94 specimens, 55, 72, and 83% were positive by culture, AFB smear, and QPCR, respectively. Of 52 culture-positive specimens, 6% were negative by PCR, and 13% were negative by AFB smear. Of 42 culture negative specimens, AFB smear and QPCR were positive in 55 and 61%, respectively. AFB smear and QPCR results were strongly correlated (r = 0.75, p < 0.001), but each correlated less strongly with culture (r = 0.54, p < 0.005 for smear and r = 0.52, p < 0.005 for QPCR). When patients were classified by microbiologic response, responders tended to have less DNA in their sputum and shorter time to a negative PCR result compared to nonresponders. These data do not suggest a great advantage of QPCR over AFB smear for predicting culture results in patients with pulmonary tuberculosis. PMID- 9368083 TI - Comparative in vitro interactions of ceftazidime, meropenem, and imipenem with amikacin on multiresistant Pseudomonas aeruginosa. AB - To evaluate the possibility of an enhanced killing effect by ceftazidime, meropenem, or imipenem with amikacin 26 multiresistant Pseudomonas aeruginosa isolates, to nine anti-pseudomonal antimicrobials of diverse chemical classes were studied. A modified time-kill curve procedure was used with a 16 micrograms/ml concentration of each antimicrobial, i.e. within the range of their serum level; a total of 248 killing-curves were performed. Any > or = 2 log10 decrease of viable cell counts by a combination compared to the most active single agent was considered an adequate enhanced killing effect. The latter was found to be mainly expressed at 24 h of growth and involved 30-50% of the tested isolates. The above findings were independent of the MIC level to any individual beta-lactam or to amikacin. It is concluded that there is no difference between the activity of the ceftazidime and amikacin combination and those of meropenem or imipenem with amikacin on multiresistant P. aeruginosa. PMID- 9368084 TI - Antimicrobial interactions (synergy) of teicoplanin with two broad-spectrum drugs (cefotaxime, ofloxacin) tested against gram-positive isolates from Germany and the United States. AB - Teicoplanin, a glycopeptide, has been widely used in some nations alone and in empiric therapy combinations to address infections caused by Gram-positive cocci. However, glycopeptide resistance and the increasing incidence of oxacillin resistant staphylococci have compromised contemporary chemotherapy. In this study, teicoplanin was tested in combinations with ampicillin, cefotaxime with and without desacetylcefotaxime, and ofloxacin against 151 Gram-positive cocci to assess the potential for enhanced action. The strains included recent isolates from the United States and Germany having well-characterized resistance mechanisms (oxacillin-resistant staphylococci, vancomycin-resistant enterococci), each tested by NCCLS methods, checkerboard synergy tests, and kill-curves. Teicoplanin alone was active (MIC90s, 0.25-2 micrograms/mL) against all species except vanA enterococci. Drug interactions of teicoplanin with beta-lactams revealed synergy and partial synergy versus oxacillin-resistant Staphylococcus spp. (67-100%) and vancomycin-resistant enterococci (70-100%), many at clinically achievable drug concentrations. However, confirming kill-curve experiments showed static action and no significant bactericidal effect. Combinations of ofloxacin with teicoplanin or cefotaxime plus desacetylcefotaxime showed a dominant additive and indifferent interaction. Teicoplanin continues to be a viable alternative to vancomycin, especially in combination therapy with selected broad spectrum cephalosporins or fluoroquinolones. Many emerging pathogens that test resistant to individual drugs appear to be inhibited by tested combinations, extending their potential clinical utility. PMID- 9368085 TI - Nosocomial enterococcal blood stream infections in the SCOPE Program: antimicrobial resistance, species occurrence, molecular testing results, and laboratory testing accuracy. SCOPE Hospital Study Group. AB - Characteristics of nosocomial enterococcal blood stream infection (NEBSI) isolates obtained from patients at 41 U.S. hospitals participating in the SCOPE Program were studied. Isolates from 480 episodes of NEBSI were characterized according to species and antimicrobial susceptibility profile. Selected isolates were also identified to species and vancomycin resistance genotype using polymerase chain reaction based methods. Polymerase chain reaction genotyping and ribotyping were used as genetic markers for molecular epidemiologic typing. Enterococci were the third most common cause of nosocomial blood stream infection in this study, accounting for 11.7% of all isolates reported. Enterococcus faecalis was the most common species (59.6%), followed by E. faecium (19.4%). Species identification errors involving E. faecium, E. durans, E. avium, and E. raffinosus were observed. Vancomycin resistance was observed in 36.4% of all participating medical centers and varied from 11.1% of medical centers in the Northwest to 60.9% of medical centers in the Southwest. Vancomycin-resistant enterococci accounted for 20.6% of NEBSI in the Northeast, 11.4% in the Southeast, 11.1% in the Southwest, and 9.5% in the Northwest regions. VanA genotypes predominated in the Northeast and Southwest, whereas vanA and vanB genotypes were equally prevalent in the Northwest and Southeast. Molecular typing studies identified strains that were unique to individual hospitals as well as strains that were prevalent in several different hospitals. NEBSI with vancomycin resistant enterococci continues to escalate among hospitalized patients in all geographic areas of the USA. PMID- 9368086 TI - In vitro antifungal activity of novel azole derivatives with a morpholine ring, UR-9746 and UR-9751, and comparison with fluconazole. AB - Thirty-three patient fungal isolates were studied by broth macrodilution methods for susceptibility to novel azole derivatives with a morpholine ring, UR-9746 and UR-9751, and fluconazole. MICs (micrograms/ml) ranged widely, but none had lower MICs for Candida albicans or Cryptococcus neoformans than UR-9751. Fluconazole and UR-9751 had the most activity versus other Candida species. Activity was demonstrated versus endemic fungal pathogens. Aspergillus species were generally resistant, although modest activity was seen. UR-9746 and UR-9751 are active in vitro, with a potency comparable to that of fluconazole. PMID- 9368087 TI - Study to determine the ability of clinical laboratories to detect antimicrobial resistant Enterococcus spp. in Buenos Aires, Argentina. AB - Few reports of vancomycin-resistant enterococci have appeared outside the USA. Therefore, we evaluated the ability of five laboratories in Buenos Aires, Argentina, to perform susceptibility testing using the disk diffusion method. Laboratories had difficulty identifying the low- and intermediate-level vancomycin-resistant phenotypes. This suggests that the disk diffusion method used by laboratories abroad may fail to detect some vancomycin-resistant enterococci. PMID- 9368089 TI - The spirit of disability. PMID- 9368090 TI - Towards an inclusive spirituality: wholeness, interdependence and waiting. AB - In this paper I want to tread a careful path between spirituality as something to be examined and spirituality as something to be experienced. While we need knowledge, the relationship between spirituality and disability exists in the experiences of those concerned, and should not be reduced to purely analytical categories. This leads me to an examination of some of the contemporary uses of the terms spirituality and disability. This is the inclusive part of the title. The paper will examine the cult of perfection as it acts to stigmatize disability. This is the wholeness part of the title. I will also examine the concept of dependence. In my view there is a need to rehabilitate this concept. This is the interdependence and waiting part of the title. What has all this to do with spirituality? It has to do with the integrity of the human person as an essentially spiritual being. PMID- 9368088 TI - Correlation of aztreonam susceptibility results obtained with the MicroScan system to reference tests. PMID- 9368091 TI - Reclaiming the whole: self, spirit, and society. AB - Science, bureaucracy and organized religion have played an important role in shaping the construction of disability--as the broken, incomplete and imperfect self, as the case requiring management, and as the object of pity and charity. This paper looks critically at the way in which concepts such as the medical model of disability and the evolving genetic model of disability have shaped the way in which we construct disability and, consequently, the way in which we treat people with disability--through isolation, segregation and elimination. These constructions of disability also operate to define and confine the spiritual journey of people with disability. The author argues for a more integrated conception of self, based not upon an empirical, mechanized and bureaucratic world-view, but upon an integrated, interdependent and holistic view of self and society. PMID- 9368093 TI - Disability, inclusion and the Christian Church: practice, paradox or promise. AB - In Western society, Christian Churches historically have been, and contemporarily are, involved with people perceived with disability. While they may practise biblical ethical imperatives such as care, compassion, mercy, support, welfare and charity, Churches have, paradoxically, only minimally offered cohesive or explicit moral notions for the 'inclusion' of people with disability in communities. Importantly, Churches have paid little attention to the historical construction of 'exclusion'. This paper proposes that matrices of patriarchal theology and patriarchal ethics continue to sustain structural positions of societal exclusion for people with disability because of implicit assumptions and values in the matrices about difference and different bodies. By examining a conjunction between feminism and disability around the issue of embodiment, the paper contends that 'inclusion' needs to be explored through the formation and embracing of matrices of feminist theology and feminist ethics. PMID- 9368092 TI - Graciosi: medieval Christian attitudes to disability. AB - To modern people, 'disability' implies a lack or an incompleteness on the part of the person so labelled when judged by the standard of the 'complete' person. For a large section of medieval society this was not the case: the 'disabled' were seen to possess special gifts which were indicative of their privileged status as recipients of God's grace. PMID- 9368094 TI - Spirituality in the lives of people with disability and chronic illness: a creative paradigm of wholeness and reconstitution. AB - To date, research within the domain of critical life events, coping, and adaptation has been mostly fragmented, outcome-oriented, and neglectful of individual differences. The aim of this research was to add a holistic understanding of the domain by using a creative hermeneutic and phenomenological perspective to understand how individuals with disability and chronic illness survive and cope successfully with their lives in spite of overwhelming odds. The lived experience of 35 informants and 14 autobiographers, who represented a wide range of people with disability and chronic illness, was used as the basis for understanding the phenomenological world of chronic conditions. Through in-depth interviews and autobiographical analysis the results were content analysed and organized into paradigm cases, exemplars and themes. Five factors that facilitated coping and adaptation were identified. The combined elements of spiritual transformation, hope, personal control, positive social supports, and meaningful engagement in life, enabled individuals to empower themselves and come to terms with their respective conditions. An overall paradigm and model of wholeness and reconstitution was also developed, which identified the processes by which people reconciled their outer forms of disability, decay or suffering and discovered an embodiment of their own inner resources and strengths. These experiences led many people to realize their own inherent sense of wholeness and unity, and to experience and integrate a deeper meaning, sense of self, and spirituality within their lives. PMID- 9368095 TI - Religion, spirituality and dementia: pastoring to sufferers of Alzheimer's disease and other associated forms of dementia. AB - The cause and effects of Alzheimer's disease still require extensive research. This paper illustrates how religion and spirituality can be related to people suffering from various forms of dementia, particularly Alzheimer's disease, and how Churches as organizations can assist these people. The paper also covers ways of minimizing communication difficulties during one-to-one pastoral visits, the simplification of religious services for nursing-home residents, and some of the problems which may occur when a practising Church minister develops symptoms of Alzheimer's disease. PMID- 9368096 TI - Being present: experiential connections between Zen Buddhist practices and the grieving process. AB - The Zen Buddhist contemplative tradition involves several meditation and instructional techniques that have strong phenomenological and theoretical connections with the experience of loss and the process of grief. From experiences which occurred during personal encounters with individuals (three of whom had a disability) in a grief counselling setting, several points of connection were identified. These included a heightened awareness of the embodied nature of experience, the importance of dialogue and relationship for both healing and transformation, the focus on process as opposed to outcome, the importance of the process of life review, a confrontation with the nature of absence and emptiness, and being present to what is experienced rather than focusing on the need for change. These findings are discussed in terms of Ken Wilber's full-spectrum model of human development, as well as their implications for professional and non-professional support persons of people experiencing grief. PMID- 9368097 TI - The pen can heal. AB - The creative arts, and in particular writing, can be very powerful as a healing therapy. This paper provides an insight into the possibility of using writing as a healing force. It follows my journey through discovery, diagnosis and experiences of neuromyopathy; yet it is a journey travelled by any person faced with a major debilitating condition, be it caused by disease or injury. It gives an insight into the needs and expectations of people who are suffering, and so promotes understanding between people with disabilities and their families, friends and health-care professionals. The added dimension of spirituality gives depth and strength to this healing force. PMID- 9368098 TI - Molecular cloning and expression pattern of the DP members of the chicken E2F transcription factor. AB - The DP proteins are components of the E2F transcription factor. They form heterodimers with the E2F proteins and these complexes bind efficiently to E2F response elements in promoters of genes that are involved in cell cycle regulation. The properties of the DP proteins are less documented than those of their E2F counterpart and the present work was aimed at characterizing avian DP genes (named chDP) and their products. Here we describe the cloning of the chicken homologues of the mammalian DP-1 and DP-2 proteins. This work also suggests that DP-2 isoforms have an additional 60 amino acid extension at the N terminus compared to its human counterpart. Gel-shift assays and coimmunoprecipitation show that both DP-1 and DP-2 dimerize to chE2F-1 and activate transcription efficiently, as demonstrated by transient expression assays. However, contrary to the expression patterns exhibited by E2F-1 during the cell cycle or during neuroretina development, DP member's expression appears more invariant, suggesting that E2F activity is limited by the availability of the E2F proteins. PMID- 9368099 TI - Display of disparate transcription phenotype by the phosphorylation negative P protein mutants of vesicular stomatitis virus, Indiana serotype, expressed in E. coli and eucaryotic cells. AB - The phosphoprotein (P) of vesicular stomatitis virus (VSV) is a subunit of the RNA polymerase (L) that transcribes the negative strand genome RNA into mRNAs both in vitro and in vivo. We have recently shown that the P protein of VSV, New Jersey serotype (PNJ), expressed in E. coli, is biologically inactive unless phosphorylated at specific serine residues by cellular casein kinase II (CKII). In the present work, we are studying the role of phosphorylation in the activation of the P protein of Indiana serotype (PIND), which is highly nonhomologous in amino acid sequence yet structurally similar to its New Jersey counterpart. Despite the fact that E. coli-expressed PIND required phosphorylation by CKII for activation, the phosphorylation negative P protein mutants generated by altering the phosphate acceptors S and T to alanine, surprisingly, showed transcription activity similar to wild-type in vitro. Alteration of S and T residues to phenylalanine, similarly, supported substantial transcription activity (approx. 60% of wild-type), whereas substitution with arginine residue abrogated transcription (approx. 5% of wild-type). In contrast, the same mutants, when expressed in eucaryotic cells, exhibited greatly reduced transcription activity in vitro. This disparate display of transcription phenotype by the PIND mutants expressed in bacteria and eucaryotic cells suggests that these mutants are unique in assuming different secondary structure or conformation when synthesized in two different cellular milieu. The findings that, unless phosphorylated by CKII, the bacterially expressed unphosphorylated (P0) form of PIND, as well as the phosphorylation negative mutants expressed in eucaryotic cells, demonstrates transcription negative phenotype indicate that, like PNJ, phosphorylation of PIND is essential for its activity. PMID- 9368100 TI - Molecular characterization of the murine Hif-1 alpha locus. AB - Hypoxia inducible factor 1 alpha (HIF-1 alpha) is a basic helix-loop-helix-PAS (bHLH-PAS) transcription factor that mediates certain cellular responses to low oxygen tension, iron chelators, Co2+, Ni2+, Mg2+, and low intracellular glucose concentration. Upon exposure to the above conditions, HIF-1 alpha is upregulated and heterodimerizes with the Ah receptor nuclear translocator (ARNT, also known as HIF-1 beta), the heterodimeric complex binds TACGTG-containing genomic enhancer elements, and activates transcription of target genes. As a first step in developing genetic models to study the biology related to cellular hypoxia, we have cloned the murine HIF-1 alpha cDNA, determined the tissue-specific expression of its mRNA, functionally analyzed its protein product, and characterized its promoter and its genomic structure. A comparison between the murine and human HIF-1 alpha protein sequence reveals 95%, 99%, and 83% identity in the bHLH, PAS, and variable domains, respectively. RNAse protection assays demonstrate that in adult mice, the mHIF-1 alpha mRNA is expressed at high levels in kidney, heart, brain, thymus, and placenta, with moderate expression in liver, spleen, testis, and lung and much lower expression in skeletal muscle testis. Northern blot analysis indicates that the mRNA of the murine HIF-1 alpha is transcribed in two forms, a major 4-kb species and a minor 5-kb species; both are present in all tissues examined. The Hif-1 alpha promoter is GC rich, does not have a TATA element near its transcriptional start site, and does not respond to hypoxia or Co2+. The mHIF-1 alpha structural gene is composed of 15 exons. The splice junction sites within the bHLH and the PAS domains of HIF-1 alpha gene are highly conserved with respect to a number of previously characterized members of the bHLH-PAS superfamily. However, unlike other bHLH-PAS genes, where the variable domain is encoded by 2 exons, the variable region of the mHIF-1 alpha gene is encoded by 7 exons. Furthermore, most of these splice junction sites in the variable region are conserved with that of HIF-2 alpha, a recently cloned hypoxia-responsive bHLH-PAS protein (also known as MOP2, EPAS1, and HLF). These data suggest that HIF-1 alpha, along with HIF-2 alpha, represents a new subclass of the bHLH-PAS superfamily. PMID- 9368101 TI - Temporal and spatial specificity of PDGF alpha receptor promoter in transgenic mice. AB - Aberrant expression of the platelet-derived growth factor alpha receptor (PDGF alpha R) has been linked to developmental abnormalities in vertebrate models, and has been implicated in multiple disease states in humans. To identify cis-acting regulatory elements that dictate expression of this receptor, we generated transgenic mice bearing the reporter gene beta-galactosidase (lacZ) under the control of a 6-kb promoter sequence. Expression of lacZ was monitored throughout embryonic development, with special focus on nervous tissue, skeleton, and several organ systems wherein PDGF alpha R expression is thought to play a pivotal role. In several independent transgenic mouse strains, lacZ expression recapitulated predominant features of PDGF alpha R gene expression during mouse development. These results demonstrate that critical tissue-specific regulatory elements for PDGF alpha R expression are located within a 6-kb upstream region of the PDGF alpha R gene. PMID- 9368103 TI - Quantitative coronary angiography with deformable spline models. AB - Although current edge-following schemes can be very efficient in determining coronary boundaries, they may fail when the feature to be followed is disconnected (and the scheme is unable to bridge the discontinuity) or branch points exist where the best path to follow is indeterminate. In this paper, we present new deformable spline algorithms for determining vessel boundaries, and enhancing their centerline features. A bank of even and odd S-Gabor filter pairs of different orientations are convolved with vascular images in order to create an external snake energy field. Each filter pair will give maximum response to the segment of vessel having the same orientation as the filters. The resulting responses across filters of different orientations are combined to create an external energy field for snake optimization. Vessels are represented by B-Spline snakes, and are optimized on filter outputs with dynamic programming. The points of minimal constriction and the percent-diameter stenosis are determined from a computed vessel centerline. The system has been statistically validated using fixed stenosis and flexible-tube phantoms. It has also been validated on 20 coronary lesions with two independent operators, and has been tested for interoperator and intraoperator variability and reproducibility. The system has been found to be specially robust in complex images involving vessel branchings and incomplete contrast filling. PMID- 9368104 TI - A simple method for automatically locating the nipple on mammograms. AB - This paper outlines a simple, fast, and accurate method for automatically locating the nipple on digitized mammograms that have been segmented to reveal the skin-air interface. If the average gradient of the intensity is computed in the direction normal to the interface and directed inside the breast, it is found that there is a sudden and distinct change in this parameter close to the nipple. A nipple in profile is located between two successive maxima of this parameter; otherwise, it is near the global maximum. Specifically, the nipple is located midway between a successive maximum and minimum of the derivative of the average intensity gradient; these being local turning points for a nipple in profile and global otherwise. The method has been tested on 24 images, including both oblique and cranio-caudal views, from two digital mammogram databases. For 23 of the images (96%), the rms error was less than 1 mm at image resolutions of 400 microns and 420 microns per pixel. Because of its simplicity, and because it is based both on the observed behavior of mammographic tissue intensities and on geometry, this method has the potential to become a generic method for locating the nipple on mammograms. PMID- 9368102 TI - Identification of transcription factories in nuclei of HeLa cells transiently expressing the Us11 gene of herpes simplex virus type 1. AB - Nuclear distribution and migration of herpes simplex virus type 1 Us11 transcripts were studied in transient expression at the ultrastructural level and compared to that of RNA polymerase II protein. Transcription was monitored by autoradiography following a short pulse with tritiated uridine. Us11 transcripts accumulated mainly over the foci of intermingled RNP fibrils as demonstrated by the presence of silver grains localizing incorporated radioactive uridine superimposed to these structures in which the presence of Us11 RNA and poly(A) tails was previously demonstrated. Silver grains were also scattered over the remaining nucleoplasm but not in the clusters of interchromatin granules, and over the dense fibrillar component of the nucleolus as in control, nontransfected HeLa cells. Pulse-chase experiments revealed the transient presence of migrating RNA in the clusters of interchromatin granules. RNA polymerase II was revealed by immunogold labeling following the use of two monoclonal antibodies: mAb H5, which recognizes the hyperphosphorylated form of the carboxy-terminal domain (CTD) of the molecule, and mAb 7C2, which recognizes both its hyperphosphorylated and unphosphorylated forms. The two mAbs bind to the newly formed Us11 transcription factories and the clusters of interchromatin granules of transfected cells. In control cells, however, clusters of interchromatin granules were labeled with mAb H5 but not with mAB 7C2. Taken together, our data demonstrate the involvement of the clusters of interchromatin granules in the intranuclear migration of Us11 RNA in transient expression. They also suggest the occurrence of changes in the accessibility of the RNA polymerase II CTD upon expression of the Us11 gene after transfection by exposing some epitopes, otherwise masked in nontransfected cells. PMID- 9368105 TI - Adaptive mammographic image enhancement using first derivative and local statistics. AB - This paper proposes an adaptive image enhancement method for mammographic images, which is based on the first derivative and the local statistics. The adaptive enhancement method consists of three processing steps. The first step is to remove the film artifacts which may be misread as microcalcifications. The second step is to compute the gradient images by using the first derivative operators. The third step is to enhance the important features of the mammographic image by adding the adaptively weighted gradient images. Local statistics of the image are utilized for adaptive realization of the enhancement, so that image details can be enhanced and image noises can be suppressed. The objective performances of the proposed method were compared with those by the conventional image enhancement methods for a simulated image and the seven mammographic images containing real microcalcifications. The performance of the proposed method was also evaluated by means of the receiver operating-characteristics (ROC) analysis for 78 real mammographic images with and without microcalcifications. PMID- 9368106 TI - Multiresolution statistical analysis of high-resolution digital mammograms. AB - A multiresolution statistical method for identifying clinically normal tissue in digitized mammograms is used to construct an algorithm for separating normal regions from potentially abnormal regions; that is, small regions that may contain isolated calcifications. This is the initial phase of the development of a general method for the automatic recognition of normal mammograms. The first step is to decompose the image with a wavelet expansion that yields a sum of independent images, each containing different levels of image detail. When calcifications are present, there is strong empirical evidence that only some of the image components are necessary for the purpose of detecting a deviation from normal. The underlying statistic for each of the selected expansion components can be modeled with a simple parametric probability distribution function. This function serves as an instrument for the development of a statistical test that allows for the recognition of normal tissue regions. The distribution function depends on only one parameter, and this parameter itself has an underlying statistical distribution. The values of this parameter define a summary statistic that can be used to set detection error rates. Once the summary statistic is determined, spatial filters that are matched to resolution are applied independently to each selected expansion image. Regions of the image that correlate with the normal statistical model are discarded and regions in disagreement (suspicious areas) are flagged. These results are combined to produce a detection output image consisting only of suspicious areas. This type of detection output is amenable to further processing that may ultimately lead to a fully automated algorithm for the identification of normal mammograms. PMID- 9368107 TI - Fully Bayesian estimation of Gibbs hyperparameters for emission computed tomography data. AB - In recent years, many investigators have proposed Gibbs prior models to regularize images reconstructed from emission computed tomography data. Unfortunately, hyperparameters used to specify Gibbs priors can greatly influence the degree of regularity imposed by such priors and, as a result, numerous procedures have been proposed to estimate hyperparameter values from observed image data. Many of these procedures attempt to maximize the joint posterior distribution on the image scene. To implement these methods, approximations to the joint posterior densities are required, because the dependence of the Gibbs partition function on the hyperparameter values is unknown. In this paper, we use recent results in Markov chain Monte Carlo (MCMC) sampling to estimate the relative values of Gibbs partition functions and using these values, sample from joint posterior distributions on image scenes. This allows for a fully Bayesian procedure which does not fix the hyperparameters at some estimated or specified value, but enables uncertainty about these values to be propagated through to the estimated intensities. We utilize realizations from the posterior distribution for determining credible regions for the intensity of the emission source. We consider two different Markov random field (MRF) models-the power model and a line-site model. As applications we estimate the posterior distribution of source intensities from computer simulated data as well as data collected from a physical single photon emission computed tomography (SPECT) phantom. PMID- 9368108 TI - Benefits of angular expression to reconstruction algorithms for collimators with spatially varying focal lengths. AB - Fan-beam collimators with spatially varying focal lengths are used in single photon emission computed tomography (SPECT) to improve the imaging sensitivity and to reduce the reconstruction artifacts resulting from the truncation of projection data. An angular representation of the detector coordinates for the projection data is adopted to investigate several aspects of the reconstruction problem for this type of collimation. A rebinning reconstruction algorithm is derived. We prove a conjecture posed by Zeng and Gullberg and obtain a simplified form of their backprojection filtering algorithm. Some computer simulations are presented to investigate the performance of the rebinning algorithm. PMID- 9368109 TI - Toward accurate attenuation correction in SPECT without transmission measurements. AB - The current trend in attenuation correction for single photon emission computed tomography (SPECT) is to measure and reconstruct the attenuation coefficient map using a transmission scan, performed either sequentially or simultaneously with the emission scan. This approach requires dedicated hardware and increases the cost (and in some cases the scanning time) required to produce a clinical SPECT image. Furthermore, if short focal-length fan-beam collimators are used for transmission imaging, the projection data may be truncated, leading to errors in the attenuation coefficient map. Our goal is to obtain information about the attenuation distribution from only the measured emission data by exploiting the fact that only certain attenuation distributions are consistent with a given emission dataset. Ultimately this consistency information will either be used directly to compensate for attenuation or combined with the incomplete information from fan-beam transmission measurements to produce a more accurate attenuation coefficient map. In this manuscript the consistency conditions (which relate the measured SPECT data to the sinogram of the attenuation distribution) are used to find the uniform elliptical attenuation object which is most consistent with the measured emission data. This object is then used for attenuation correction during the reconstruction of the emission data. The method is tested using both simulated and experimentally acquired data from uniformly and nonuniformly attenuating objects. The results show that, for uniform elliptical attenuators, the consistency conditions of the SPECT data can be used to produce an accurate estimate of the attenuation map without performing any transmission measurements. The results also show that, in certain circumstances, the consistency conditions can prove useful for attenuation compensation with nonuniform attenuators. PMID- 9368110 TI - Three-dimensional PET emission scan registration and transmission scan synthesis. AB - The duration of a positron emission tomography (PET) imaging scan can be reduced if the transmission scan of one patient which is used for emission correction can be synthesized by using the reference transmission scan of another patient. In this paper, we propose a new intersubjects PET emission scan registration method and PET transmission synthesis method by using the boundary information of the body or brain scan of the PET emission scans. The PET emission scans have poor image quality and different intensity statistics so that we preprocess the emission scans to have similar histogram and then apply the point distribution model (PDM) [15] to extract the contours of the emission scan. The extracted boundary contour of every slice is used to reconstruct the three-dimensional (3 D) surface of the reference set and the target set. Our registration is 3-D surface-based which uses the normal flow method [17] to find the correspondence vector field between two 3-D reconstructed surfaces. Since it is difficult to analyze internal organ using the PET emission scan imaging without correction, we assume that the deformation of internal organ is homogeneous. With the corresponding vector field between the two emission scans and the transmission scan of the reference set, we can synthesize the transmission scan of the target set. PMID- 9368111 TI - Regularized reconstruction in electrical impedance tomography using a variance uniformization constraint. AB - This paper describes a new approach to reconstruction of the conductivity field in electrical impedance tomography. Our goal is to improve the tradeoff between the quality of the images and the numerical complexity of the reconstruction method. In order to reduce the computational load, we adopt a linearized approximation to the forward problem that describes the relationship between the unknown conductivity and the measurements. In this framework, we focus on finding a proper way to cope with the ill-posed nature of the problem, mainly caused by strong attenuation phenomena; this is done by devising regularization techniques well suited to this particular problem. First, we propose a solution which is based on Tikhonov regularization of the problem. Second, we introduce an original regularized reconstruction method in which the regularization matrix is determined by space-uniformization of the variance of the reconstructed condictivities. Both methods are nonsupervised, i.e., all tuning parameters are automatically determined from the measured data. Tests performed on simulated and real data indicate that Tikhonov regularization provides results similar to those obtained with iterative methods, but with a much smaller amount of computations. Regularization using a variance uniformization constraint yields further improvements, particularly in the central region of the unknown object where attenuation is most severe. We anticipate that the variance uniformization approach could be adapted to iterative methods that preserve the nonlinearity of the forward problem. More generally, it appears as a useful tool for solving other severely ill-posed reconstruction problems such as eddy current tomography. PMID- 9368112 TI - Anatomically constrained electrical impedance tomography for three-dimensional anisotropic bodies. AB - As shown previously for two-dimensional geometries, anisotropy effects should not be ignored in electrical impedance tomography (EIT) and structural information is important for the reconstruction of anisotropic conductivities. Here, we will describe the static reconstruction of an anisotropic conductivity distribution for the more realistic three-dimensional (3-D) case. Boundaries between different conductivity regions are anatomically constrained using magnetic resonance imaging (MRI) data. The values of the conductivities are then determined using gradient-type algorithms in a nonlinear-indirect approach. At each iteration, the forward problem is solved by the finite element method. The approach is used to reconstruct the 3-D conductivity profile of a canine torso. Both computational performance and simulated reconstruction results are presented together with a detailed study on the sensitivity of the prediction error with respect to different parameters. In particular, the use of an intracavity catheter to better extract interior conductivities is demonstrated. PMID- 9368113 TI - Automatic tracking of the aorta in cardiovascular MR images using deformable models. AB - We present a new algorithm for the robust and accurate tracking of the aorta in cardiovascular magnetic resonance (MR) images. First, a rough estimate of the location and diameter of the aorta is obtained by applying a multiscale medial response function using the available a priori knowledge. Then, this estimate is refined using an energy-minimizing deformable model which we define in a Markov random-field (MRF) framework. In this context, we propose a global minimization technique based on stochastic relaxation, Simulated annealing (SA), which is shown to be superior to other minimization techniques, for minimizing the energy of the deformable model. We have evaluated the performance and robustness of the algorithm on clinical compliance studies in cardiovascular MR images. The segmentation and tracking has been successfully tested in spin-echo MR images of the aorta. The results show the ability of the algorithm to produce not only accurate, but also very reliable results in clinical routine applications. PMID- 9368114 TI - Constrained reconstruction applied to 2-D chemical shift imaging. AB - The method of constrained reconstruction, previously applied to magnetic resonance imaging (MRI), is extended to magnetic resonance spectroscopy. This method assumes a model for the MR signal. The model parameters are estimated directly from the phase encoded data. This process obviates the need for the fast Fourier transform (FFT) (which often exhibits limited resolution and ringing artifact). The technique is tested on simulated data, phantom data, and data acquired from human liver in vivo. In each case, constrained reconstruction offers spatial resolution superior to that obtained with the FFT. PMID- 9368115 TI - Multiple sclerosis lesion quantification using fuzzy-connectedness principles. AB - Multiple sclerosis (MS) is a disease of the white matter. Magnetic resonance imaging (MRI) is proven to be a sensitive method of monitoring the progression of this disease and of its changes due to treatment protocols. Quantification of the severity of the disease through estimation of MS lesion volume via MR imaging is vital for understanding and monitoring the disease and its treatment. This paper presents a novel methodology and a system that can be routinely used for segmenting and estimating the volume of MS lesions via dual-echo fast spin-echo MR imagery. A recently developed concept of fuzzy objects forms the basis of this methodology. An operator indicates a few points in the images by pointing to the white matter, the grey matter, and the cerebro-spinal fluid (CSF). Each of these objects is then detected as a fuzzy connected set. The holes in the union of these objects correspond to potential lesion sites which are utilized to detect each potential lesion as a three-dimensional (3-D) fuzzy connected object. These objects are presented to the operator who indicates acceptance/rejection through the click of a mouse button. The number and volume of accepted lesions is then computed and output. Based on several evaluation studies, we conclude that the methodology is highly reliable and consistent, with a coefficient of variation (due to subjective operator actions) of 0.9% (based on 20 patient studies, three operators, and two trials) for volume and a mean false-negative volume fraction of 1.3%, with a 95% confidence interval of 0%-2.8% (based on ten patient studies). PMID- 9368116 TI - Fully automatic identification of AC and PC landmarks on brain MRI using scene analysis. AB - We describe a method for identification of brain structures from MRI data sets. The bulk of the paper concerns an automatic system for finding the anterior and posterior commissures [(AC) and (PC)] in the midsagittal plane. These landmarks are key for the definition of the Talairach space, commonly used in stereotactic neurosurgery, in the definition of common coordinate systems for the pooling of functional positron emission tomography (PET) images and for neuroanatomy studies. The process works according to a step-by-step procedure: it first analyzes the skull limits. A grey-level histogram is then calculated and allows an automated selection of thresholds. Then, the interhemispheric plane is detected. Following an advanced scene analysis in the midsagittal plane for anatomical structures, the AC and the PC are identified. Experimentally, with a set of 200 patients, the process never failed. Its performances and limits are comparable to that of neuroanatomy experts. Those results are due to a high degree of robustness at each step of the program. PMID- 9368117 TI - Measurement of AC magnetic field distribution using magnetic resonance imaging. AB - Electric currents are applied to body in numerous applications in medicine such as electrical impedance tomography, cardiac defibrillation, electrocautery, and physiotherapy. If the magnetic field within a region is measured, the currents generating these fields can be calculated using the curl operator. In this study, magnetic fields generated within a phantom by currents passing through an external wire is measured using a magnetic resonance imaging (MRI) system. A pulse sequence that is originally designed for mapping static magnetic field inhomogeneity is adapted. AC current in the form of a burst sine wave is applied synchronously with the pulse sequence. The frequency of the applied current is in the audio range with an amplitude of 175-mA rms. It is shown that each voxel value of sequential images obtained by the proposed pulse sequence is modulated similar to a single tone broadband frequency modulated (FM) waveform with the ac magnetic field strength determining the modulation index. An algorithm is developed to calculate the ac magnetic field intensity at each voxel using the frequency spectrum of the voxel signal. Experimental results show that the proposed algorithm can be used to calculate ac magnetic field distribution within a conducting sample that is placed in an MRI system. PMID- 9368118 TI - The boundary shift integral: an accurate and robust measure of cerebral volume changes from registered repeat MRI. AB - We propose the boundary shift integral (BSI) as a measure of cerebral volume changes derived from registered repeat three-dimensional (3-D) magnetic resonance (MR) [3D MR] scans. The BSI determines the total volume through which the boundaries of a given cerebral structure have moved and, hence, the volume change, directly from voxel intensities. We found brain and ventricular BSI's correlated tightly (r = 1.000 and r = 0.999) with simulated volumes of change. Applied to 21 control scan pairs and 11 scan pairs from Alzheimer's disease (AD) patients (mean interval 386 days) the BSI yielded mean brain volume loss of 1.8 cc (controls) and 34.7 cc (AD); the control group was tightly bunched (SD = 3.8 cc) and there was wide group separation, the group means differing by 8.7 control group standard deviations (SD's). A measure based on the same segmentation used by the BSI yielded similar group means, but wide spread in the control group (SD = 13.4 cc) and group overlap, the group means differing by 2.8 control group SD's. The BSI yielded mean ventricular volume losses of 0.4 cc (controls) and 10.1 cc (AD). Good linear correlation (r = 0.997) was obtained between the ventricular BSI and the difference in their segmented volumes. We conclude the BSI is an accurate and robust measure of regional and global cerebral volume changes. PMID- 9368119 TI - Three-dimensional surface reconstruction using optical flow for medical imaging. AB - The recovery of a three-dimensional (3-D) model from a sequence of two dimensional (2-D) images is very useful in medical image analysis. Image sequences obtained from the relative motion between the object and the camera or the scanner contain more 3-D information than a single image. Methods to visualize the computed tomograms can be divided into two approaches: the surface rendering approach and the volume rendering approach. In this paper, a new surface rendering method using optical flow is proposed. Optical flow is the apparent motion in the image plane produced by the projection of the real 3-D motion onto 2-D image. The 3-D motion of an object can be recovered from the optical-flow field using additional constraints. By extracting the surface information from 3-D motion, it is possible to get an accurate 3-D model of the object. Both synthetic and real image sequences have been used to illustrate the feasibility of the proposed method. The experimental results suggest that the proposed method is suitable for the reconstruction of 3-D models from ultrasound medical images as well as other computed tomograms. PMID- 9368120 TI - A methodology for evaluation of boundary detection algorithms on medical images. AB - Image segmentation is the partition of an image into a set of nonoverlapping regions whose union is the entire image. The image is decomposed into meaningful parts which are uniform with respect to certain characteristics, such as gray level or texture. In this paper, we propose a methodology for evaluating medical image segmentation algorithms wherein the only information available is boundaries outlined by multiple expert observers. In this case, the results of the segmentation algorithm can be evaluated against the multiple observers' outlines. We have derived statistics to enable us to find whether the computer generated boundaries agree with the observers' hand-outlined boundaries as much as the different observers agree with each other. We illustrate the use of this methodology by evaluating image segmentation algorithms on two different applications in ultrasound imaging. In the first application, we attempt to find the epicardial and endocardial boundaries from cardiac ultrasound images, and in the second application, our goal is to find the fetal skull and abdomen boundaries from prenatal ultrasound images. PMID- 9368121 TI - Wavelet representations for monitoring changes in teeth imaged with digital imaging fiber-optic transillumination. AB - Digital imaging fiber-optic transillumination (DI-FOTI) is a novel method to detect and monitor dental caries, using light, a charge-coupled device (CCD) camera, and computer-controlled image acquisition. The advantages of DIFOTI over radiography include: no ionizing radiation, no film, real-time diagnosis, and higher sensitivity in detection of early lesions not apparent to X-ray, as demonstrated in vitro. Here, we present a method of processing DIFOTI images, acquired at different times, for monitoring changes. Of central importance to this application is pattern matching of image frames that is invariant to translation and rotation of a tooth, relative to the field of view of the imaging camera, and that is robust to changes in illumination source intensity. Our method employs: 1) wavelet modulus maxima representations for segmentation of teeth images; 2) first and second moments of gray level representations of DIFOTI images in the spatial domain, to estimate tooth location and orientation; and 3) multiresolution wavelet magnitude representations for quantitative monitoring. Even with illumination source intensity variation, it is demonstrated in vitro that such wavelet representations can facilitate detection of simulated clinical changes in light transmission that cannot be detected in the spatial domain. PMID- 9368122 TI - A system for digital reconstruction of gypsum dental casts. AB - A range scanner is developed that can scan a gypsum dental cast and reconstruct the cast digitally for display and storage purposes. The scanner is based on subtractive light and computes the range values using optical triangulation. A fiducial marker is introduced that, when attached to a dental cast at the time of image acquisition, makes it possible to integrate multiview range images of the cast without image registration. A method for calibrating the scanner is described and experimental results showing the accuracy of the scanner are presented. PMID- 9368123 TI - Consolidation of common parameters from multiple fits in dynamic PET data analysis. AB - In dynamic positron emission tomography (PET) data analysis, regions of interest (ROI's) are analyzed by fitting a parametric model to the time-activity curve acquired after a radio-labeled tracer has been introduced into the patient's bloodstream. This procedure can be carried out for multiple ROI's and/or multiple injections of the same or a different radiopharmaceutical. The approach presented here takes advantage of prior knowledge that some of the parameters of those multiple fits are the same. Reduction of the total number of parameters to be estimated results in smaller statistical uncertainty for all parameter estimates, especially those common to multiple fits. PMID- 9368124 TI - The design of an animal PET: flexible geometry for achieving optimal spatial resolution or high sensitivity. AB - We present the design of a positron emission tomograph (PET) with flexible geometry dedicated to in vivo studies of small animals (TierPET). The scanner uses two pairs of detectors. Each detector consists of 400 small individual yttrium aluminum perovskite (YAP) scintillator crystals of dimensions 2 x 2 x 15 mm3, optically isolated and glued together, which are coupled to position sensitive photomultiplier tubes (PSPMT's). The detector modules can be moved in a radial direction so that the detector-to-detector spacing can be varied. Special hardware has been built for coincidence detection, position detection, and real time data acquisition, which is performed by a PC. The single-event data are transferred to workstations where the radioactivity distribution is reconstructed. The dimensions of the crystals and the detector layout are the result of extensive simulations which are described in this report, taking into account sensitivity, spatial resolution and additional parameters like parallax error or scatter effects. For the three-dimensional (3-D) reconstruction a genuine 3-D expectation-maximization (EM)-algorithm which can include the characteristics of the detector system has been implemented. The reconstruction software is flexible and matches the different detector configurations. The main advantage of the proposed animal PET scanner is its high flexibility, allowing the realization of various detector-system configurations. By changing the detector-to-detector spacing, the system is capable of either providing good spatial resolution or high sensitivity for dynamic studies of pharmacokinetics. PMID- 9368126 TI - Parent-adolescent interactions and psychosocial risk in adolescents: an analysis of communication, support and gender. AB - The main purpose of this study was to verify the correlation between family functioning and the presence of psychosocial risk in adolescents. The sample of 279 intact families with a late adolescent and their parents complete self-report instruments in order to evaluate support and communication in parent-adolescent relationships. An index of risk was constructed with the MAUT technique. Data analysis was conducted on individual and relational dyadic levels. It was found that: (a) a supportive relationship and adequate communication between parents and adolescents are correlated to the absence or presence of psychosocial risk; and (b) the father in this phase of life is a reliable source of information regarding his relationship with his children and their psychosocial adjustment. PMID- 9368125 TI - Development of a vertebral endplate 3-D reconstruction technique. AB - The increase of low back problems has stimulated the development of different analysis and evaluation techniques. Among these methods, the direct linear transformation (DLT) technique is commonly used to reconstruct the spine in three dimensions by means of its known image coordinates on radiographs. Despite its efficiency and precision, general reconstruction of some standard anatomical landmarks (7-11) does not give all the necessary data for a detailed analysis of the intrinsic geometrical characteristics of lumbar vertebrae. Thus, in order to obtain such geometrical information a three-dimensional (3-D) reconstruction vertebral endplate contour technique has been developed. This technique involves 1) iterative optimization and reconstruction processes of the vertebral endplate centroid and 2) 3-D reconstruction of vertebral endplate contour. Validation based on mathematical simulations demonstrated that two or three iterations are necessary to correct (within 2 mm) the endplate centroid position for simulated error higher than 10 mm. Other validations based on 3-D reconstructions of a chamfered tube and a dry vertebra contours of known dimensions have given mean errors of 2 mm. Application on a healthy subject demonstrated the potential of this 3-D reconstruction technique. Finally, 3-D data obtained on vertebral endplates would allow the development of new clinical measurements that could be used to evaluate the lumbar spine geometrical behavior and orthoses biomechanical effects. PMID- 9368127 TI - Locus of control and problem-solving interaction in families with adolescents. AB - The focus of this study is on further development and refinement of a classification system of family problem-solving interaction in families with adolescents. A rigorous qualitative analysis was conducted on the video-taped problem-solving sessions of 38 families which consisted of a father, mother and their adolescent son or daughter. The analysis concentrated on how families engaged the problem situations, how solutions were generated and evaluated, communication patterns, and how affect was managed. It was discovered through the analysis that family problem-solving interaction could be classified based on a concept the researchers call family locus of control (F-LOC). Four types of F-LOC were described: individualistic, collaborative, authoritarian and external. Internal classification reliability was assessed by three independent raters who were able to accurately classify 95% of the problem-solving sessions by F-LOC. Discussion focuses on comparing the classification system with previously developed classification systems. PMID- 9368128 TI - Teenage mothers as breastfeeders: attitudes and behaviour. AB - Surveys have repeatedly shown that teenage mothers are less likely to breastfeed than older mothers. A sample of 55 young mothers and expectant mothers contacted through agencies caring for young mothers revealed that decisions about breastfeeding are sometimes left till late in the pregnancy, and that breastfeeding is often of short duration. Only about half had discussed breastfeeding with a health worker. As with older mothers, the partners and the teenagers' own mothers often influenced their decision, sometimes in a hostile way. Many young mothers had never witnessed breastfeeding at first-hand. These results suggest ways in which breastfeeding could be more successfully promoted among young mothers. PMID- 9368129 TI - Combining cultural, social and personality trait variables as predictors for drug use among adolescents in Zimbabwe. AB - A classroom survey among 3061 secondary school students in four provinces in Zimbabwe was conducted in 1994. This paper presents analyses of the relationship between a set of predictors including personality trait, social and cultural variables and drug use. A two-stage sampling strategy distinguished between four different socio-cultural groups. Multiple regression was applied to analyse the impact of sensation-seeking, addictive behaviour of significant others, and Global and Local cultural orientation on drug use, controlling for age, gender and socio-cultural subgroup. The model explained 29.7% of the variance in the dependent drug use variable and the two cultural orientation variables were found to contribute significantly in addition to the personality trait and the social variables. PMID- 9368130 TI - School adjustment, school membership and adolescents' future expectations. AB - Two studies investigated how students' school adjustment and sense of school membership relates to their future expectations. In Study 1 measures of future expectations, school membership and school adjustment were administered to a random sample of 307 5th-12th grade (male and female) students in 16 schools. Correlations among the measures were significant, and no meaningful grade differences were found on these variables. Multiple regression analysis showed that students' social acceptance in school predicted future expectations. Study 2 replicated Study 1 using 164 female students (i.e. the entire student population of one high school) as subjects. Findings of Study 2 also support the conclusion that students' school experiences, particularly with peers, shape their future expectations. PMID- 9368131 TI - The covariation of religion and politics during the transition to young adulthood: challenging global identity assumptions. AB - This study was undertaken to examine the relation between religion and politics in terms of identity and beliefs, as well as the relations among identity and beliefs, during the transition to young adulthood. Data were obtained from 209 college students using self-administered questionnaires. Constructs included religious and political identity diffusion, foreclosure, moratorium and achievement, as well as intrinsic religiosity, church/temple importance, Christian orthodoxy, political involvement, and faith in government. Correlational analyses revealed that the only significant relations between religion and politics was for identity foreclosure and moratorium, and that none of the religious beliefs were significantly correlated with political beliefs. Hierarchical regression analyses, controlling for gender and year in college, indicated that religious diffusion proved to be the most powerful (negative) predictor of religious beliefs; similarly, political diffusion was the most powerful (negative) predictor of political involvement. Religious achievement was associated with higher levels of intrinsic religiosity. The findings provide additional validity for the construct of identity diffusion. At the same time, the inconsistent and low covariation between religious and political identity suggests that focus on global identity has limited utility. PMID- 9368132 TI - The relationships among parent-adolescent differentiation, sex role orientation and identity development in late adolescence and early adulthood. AB - This study had three main objectives. The first was an attempt to clarify inconsistencies in research on family characteristics and identity formation. The second was to test a model that has been discussed over the past several years based on Bowen's intergenerational family systems theory. Finally, gender differences were explored within the models hypothesized. The models included family differentiation variables, sex role orientation and adolescent identity development. The path models that included mother/adolescent and father/adolescent differentiation, masculinity and femininity scales, and ideological and interpersonal identity achievement in separate analyses were tested using LISREL VII. The results suggested that interpersonal and ideological identity domains were differentially related to differentiation in the family system and sex role orientation. There were also gender differences. These results are discussed in relation to previous research evidence about family characteristics that best support identity achievement for males and females. PMID- 9368133 TI - Adolescents' experiences of anger in a residential setting. AB - There is a substantial literature, covering a range of populations, looking at the phenomenon of anger and its expression. However, remarkably little is known about adolescent experiences of anger. The present study looks at adolescent anger within the confines of a residential establishment. Using a qualitative methodology to consider young peoples' own account of anger-provoking incidents, a description is given of typical settings, reactions, and outcomes in angry incidents. The implications of this information for both staff training and anger management programmes is explored. PMID- 9368134 TI - An empirical test of the identity capital model. AB - In a previous issue of this journal, the identity capital model was presented as part of an effort to better understand the relationship between social context and identity formation (Cote, 1996a). The present paper provides an empirical test of that model as it applies to the late-adolescent passage of university students toward adulthood. A series of research questions are explored which reveal the following: (1) concepts used in the model can be reliably measured; (2) significant relationships exist among certain measures of identity capital resources; (3) these resources have significant associations with measures of identity capital acquisition; (4) over 2 years of university, identity capital increases overall for female students (on a measure of adult identity resolution) and for those of lower social class background (on a measure of community identity resolution); and (5) certain resources acquired before attending university are predictors of identity capital acquisition after 2 years of attendance, net of the identity capital with which students begin university. PMID- 9368135 TI - Bioactive bone cement: comparison of AW-GC filler with hydroxyapatite and beta TCP fillers on mechanical and biological properties. AB - Three types of bioactive bone cement (designated AWC, HAC, and TCPC), each consisting of bisphenol-alpha-glycidyl methacrylate (Bis-GMA)-based resin and a bioactive filler of apatite and wollastonite containing glass-ceramic (AW-GC), sintered hydroxyapatite (HA), or beta-tricalcium phosphate (beta-TCP) powder were made in order to evaluate the influence of the bioactive filler on the mechanical and biological properties of bone cement. The proportion of filler added to the cements was 70% w/w. The compressive, bending, and tensile strengths and the fracture toughness of AWC were higher than HAC and TCPC under wet conditions. The cements were evaluated in vivo by packing them into the intramedullary canals of rat tibiae. An affinity index that equalled the length of bone in direct apposition to the cement was calculated for each cement and expressed as a percentage of the total length of the cement surface. Histological examination of rat tibiae up to 8 weeks after implantation revealed that AWC had higher bioactivity than HAC and TCPC. New bone had formed along the AWC surface within 2 weeks, and at 4 weeks newly formed bone surrounded the cement surface almost completely. In HAC- and TCPC-implanted tibiae, immature bone had formed directly toward but not along the cement surface at 2 weeks. Observation of cement-bone interfaces showed that AWC had bonded to the bone via a so-called "Ca-P-rich layer"; the cement-bone interface remained stable, and the width of the CA-P-rich layer became thicker with time. On the other hand, in HAC- and TCPC-implanted tibiae, the cement surface fillers were surrounded by new bone and were absorbed gradually to become bone matrix. The cement-bone interfaces went inside the cement with time. Our results indicate that stronger interstitial bonding between the inorganic filler and the organic matrix resin in AWC lead to higher mechanical properties; results also indicate that the more stable cement-bone interface and higher bioactivity of AWC are due to early and uniform apatite formation on the cement surface. PMID- 9368136 TI - Effect of single-chain and two-chain high molecular weight kininogen on adsorption of fibrinogen from binary mixtures to glass and sulfonated polyurethane surfaces. AB - The adsorption of fibrinogen from a single protein solution and from binary mixtures of fibrinogen and high-molecular-weight kininogen (HK) to glass and four sulfonated polyurethane surfaces is reported. The effect of the single-chain (SCHK) and two-chain (TCHK) forms of HK on fibrinogen adsorption was investigated. Using radiolabeling methods, fibrinogen adsorption from a series of mixtures having the same weight ratio of fibrinogen to HK as in plasma (50:1), but varying in total concentration, was measured. Fibrinogen adsorption from the mixtures was reduced on all surfaces compared to the single-protein solution, confirming the highly surface-active nature of this protein. However, except for glass, there was no significant difference between the SCHK and TCHK forms. Polyacrylamide gel electrophoresis and immunoblotting analysis of the proteins eluted from the surfaces after contact with the fibrinogen-SCHK solutions indicated that although intact SCHK was essentially conserved, some transformation of SCHK to TCHK on the surface occurred during the course of the experiment. It is hypothesized that in purified form, in which HK is not complexed to prekallikrein or factor XI, the surface-binding domain is more available than in the complexed forms which are present in plasma. If so, then the removal of bradykinin by kallikrein, as occurs in generating TCHK, may not be required for the expression of surface-binding domain activity. PMID- 9368137 TI - The effects of calcium phosphate particles on the growth of osteoblasts. AB - With advances in ceramics technology, calcium phosphate bioceramics have been applied as bone substitutes for several decades. The focus of this work is to elucidate the biocompatibility of the particulates of various calcium phosphate cytotoxicities. Four different kinds of calcium phosphate powders, including beta tricalcium phosphate (beta-TCP), hydroxyapatite (HA), beta-dicalcium pyrophosphate (beta-DCP), and sintered beta-dicalcium pyrophosphate (SDCP), were tested by osteoblast cell culture. The results were analyzed by cell count, concentration of transforming growth factor-beta 1 (TGF-beta 1), alkaline phosphatase (ALP), and prostaglandin E2 (PGE2) in culture media. The changes were most significant when osteoblasts were cultured with beta-TCP and HA bioceramics. The changes in cell population of the beta-TCP and HA were quite low in the first 3 days, then increased gradually toward the seventh day. The changes in TGF-beta 1 concentration in culture medium inversely related to the changes in cell population. The ALP titer in the culture media of the beta-TCP and HA were quite high in the first 3 days, then decreased rapidly between the third and seventh days. The concentrations of PGE2 in the culture media tested were quite high on the first day, decreased rapidly to the third day, and then gradually until the seventh day. The changes in the beta-DCP and SDCP were quite similar to those of HA and beta-TCP but much less significant. We conclude that HA and beta-TCP have an inhibitory effect on the growth of osteoblasts. The inhibitins effects of the HA and beta-TCP powders on the osteoblast cell cultures possibly are mediated by the increased synthesis of PGE2. PMID- 9368138 TI - In vitro and in vivo mechanical evaluations of plasma-sprayed hydroxyapatite coatings on titanium implants: the effect of coating characteristics. AB - This study was undertaken to evaluate the effect of coating characteristics on the mechanical strengths of the plasma-sprayed HA-coated Ti-6Al-4V implant system both in vitro and in vivo. Two types of HA coatings (HACs) with quite different microstructures, concentrations of impurity-phases, and indices-of-crystallinity were used. In vitro testings were done by measuring the bonding-strength at the Ti-6Al-4V-HAC interface, with HACs that had and had not been immersed in a pH buffered, serum-added simulated body fluid (SBF). The shear-strength at the HAC bone interface was investigated in a canine transcortical femoral model after 12 and 24 weeks of implantation. The results showed a bonding degradation of approximately 32% or higher of the original strength after 4 weeks of immersion in SBF, and this predominantly depended on the constructed microstructure of the HACs. After the push-out measurements, it was demonstrated that the HACs with higher bonding-strength in vitro would correspondingly result in significantly higher shear-strength at each implant period in vivo. Nevertheless, there were no substantial histological variations between the two types of HACs evaluated. The most important point elucidated in this study was that, among coating characteristics, the microstructure was the key factor in influencing the mechanical stability of the HACs both in vitro and in vivo. As a consequence, a denser HAC was needed to ensure mechanical stability at both interfaces. PMID- 9368139 TI - Osteoclastic resorption of biphasic calcium phosphate ceramic in vitro. AB - Neonatal rabbit bone cells were cultured for 1 and 4 days on biphasic calcium phosphate ceramic specimens to study the osteoclastic resorption of the ceramic. Scanning electron microscopic studies after removal of stromal cells with pronase E and EDTA revealed many osteoclast-associated lacunae on the ceramic surface. The degraded crystals inside the lacunae appeared to have been dissolved by acids. Cellular degradation of the ceramic was clearly due to the extracellular process characteristic of osteoclastic resorption. PMID- 9368140 TI - Fiber-matrix interface studies on bioabsorbable composite materials for internal fixation of bone fractures. II. A new method using laser scanning confocal microscopy. AB - In this study, a new visual characterization method was developed using laser scanning confocal microscopy (LSCM) to study morphologic properties, particularly at the fiber-matrix interface, by optical sectioning of bioabsorbable single fiber composites. The interface gap width (IGW) between the fiber and matrix, and the changes in IGW after in vitro hydrolysis, named the gap rate (Rg), were measured from images obtained using the LSCM. Higher values for IGW and Rg showed faster degradation of the fiber-matrix interface. These parameters were used to investigate the effects of strain, wicking, different reinforcing fibers, and gamma-irradiation on the fiber-matrix interface morphology. The component materials used were nonbioabsorbable AS4 carbon (C) fibers, bioabsorbable calcium phosphate (CaP), poly(glycolic acid) (PGA), and chitin fibers, and bioabsorbable poly(L-lactic acid) (PLLA) matrix. The application of strain on CaP/PLLA composites increased the IGW up to about 15%, after which there was no change up to 25%. The Rg for CaP/PLLA composites with the fiber ends exposed in vitro (permitting wicking) was greater than for CaP/PLLA with the fiber ends embedded completely within the matrix (preventing wicking). Open-end C/PLLA composites had the slowest rate of interface degradation in vitro, followed by chitin/PLLA, PGA/PLLA, and CaP/PLLA. The exposure of closed-end CaP/PLLA composites to 4 Mrad of gamma-irradiation, in air at room temperature or in vaccuum at 77K, accelerated the rate of interface degradation in vitro. In conclusion, an effective new visual characterization method was developed using LSCM, and it was used to show that (a) moderate strain could accelerate the degradation of the interface, (b) fiber-matrix interface wicking could accelerate the rate of degradation of the interface, (c) the rate of interface degradation depends on the type of fiber used, and (d) gamma-irradiation could accelerate the rate of interface degradation. Furthermore, the results of LSCM analysis of different reinforcing fibers with a PLLA matrix agree with measurements of interfacial shear strength (IFSS) and single-fiber tensile strength reported in Part I of this study. PMID- 9368141 TI - The effect of in vitro modeling conditions on the surface reactions of bioactive glass. AB - Using one parametric variation in solution composition, this paper documents that the surface reactions on bioactive glass (BG) 45S5 are exquisitely dependent upon the modeling conditions. The solutions used were 0.05 M tris hydroxymethyl aminomethane/HCl (tris buffer), tris buffer complemented with plasma electrolyte and/or serum, and serum. The reacted surfaces were analyzed using Fourier transform infrared (FTIR), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDXA), and Rutherford backscattering spectroscopy (RBS). Post-immersion solutions were analyzed for changes in Ca and PO4 concentrations. After a short immersion (3 h), a crystalline, carbonated hydroxyapatite (c-HA) layer formed only in tris. Reaction surfaces of different structure, morphology, and composition were observed after various short and longer term immersions in all other solutions. They comprised two layers with the layer in contact with the bulk consisting mainly of Si; the outer layer, composed of Si, Ca, and P, was amorphous, and had a Ca/P ratio of about 1. Serum proteins adsorbed on the BG surfaces at the early stages of the solution-mediated BG reactions. Formation of a crystalline c-HA layer was delayed up to three or more days in solution with plasma ions. In the presence of serum, only amorphous surfaces composed of Si, Ca, and P were observed for any time up to seven days of immersion. The present data suggest that serum proteins adsorb in tandem with the occurrence of solution-mediated reactions leading to formation of a silica-gel. Amorphous Ca-P phases accumulate in the Si-rich matrix. Furthermore, the present data, in conjunction with the data published before, suggest that physicochemical and cell-mediated reactions occur in parallel to form the glass-tissue interfacial layer. PMID- 9368142 TI - Effects of various chemical sterilization methods on the crosslinking and enzymatic degradation characteristics of an epoxy-fixed biological tissue. AB - Due to the nature of bioprostheses, which are mainly biological tissues that cannot be sterilized with heat or irradiation, the sterilization method by choice is generally liquid chemicals. It is known that a number of liquid chemicals can have rapid germicidal effect and can be used to sterilize bioprostheses. The study was to evaluate the effects of various chemical sterilization methods on the crosslinking and enzymatic degradation characteristics of an epoxy-fixed biological tissue. The chemical sterilants employed were: a 70% ethanol solution (EtOH), a 2% epoxy compound + 20% ethanol solution (EX-810), a 2% propylene oxide + 20% ethanol solution (PO), and a 0.625% glutaraldehyde + 20% ethanol + 0.2% polysorbate solution (GA). Both masking and crosslinking of the free amino groups within the epoxy-fixed tissue were observed subsequent to sterilization with GA or EX-810. This improved the resistance of the GA or EX-810 sterilized tissues against collagenase degradation as compared to its nonsterilized counterpart. However, subsequent to sterilization with PO, only masking of the free amino groups within the epoxy-fixed tissue was noted. The inhibition of the collagenase degradation by masking of the free amino groups was traded off by the more random molecular packing of the PO sterilized sample due to the introduction of the side branches. Sterilization of the epoxy-fixed tissue with EtOH may increase its denaturation temperature and tensile strength, while neither masking nor crosslinking of free amino groups within the tissue took place. The resistance to degradation of the EtOH sterilized tissue, however, did not improve as compared to its nonsterilized counterpart. PMID- 9368143 TI - Histologic and mechanical evaluation for bone bonding of polymer surfaces grafted with a phosphate-containing polymer. AB - A phosphate-containing polymer was covalently immobilized onto a polyethylene (PE) rod, a poly(ethylene terephthalate) (PET) thread, and a PET film by a surface graft polymerization technique, followed by immersion in calcium phosphate solution to deposit a thin hydroxyapatite (HA) layer on the modified polymer surfaces. The PE rod had a tapered shape, while the PET thread was fixed with clips after implantation, both to minimize the micromovement which may occur in bone. The PE rod was implanted through press-fitting in the femur of rat. Significant enhancement was observed for direct contact of the implant surface with a newly formed bone for both the grafted only and the further HA-deposited PE rods in comparison with the untreated PE at 4, 5, and 6 weeks after implantation. The rats implanted with the modified PET thread in the femur were sacrificed 3 and 6 weeks after implantation. Statistically significant differences were observed for the untreated versus the grafted plus HA-deposited rods at 6 weeks after implantation. To study the resorption of the deposited HA on the methacryloyloxyethylene phosphate-grafted surface, HA-deposited PET films were subcutaneously implanted in the back of rats. The deposited HA was rapidly resorbed within 3 weeks of implantation. These results suggest that the phosphate polymer chains grafted on the PE and PET surfaces effectively induced nucleation and growth of HA crystals. It seems likely that the thin HA layer additionally deposited in vitro onto the grafted PE and PET surfaces was resorbed rapidly and then promoted the growth of HA crystals in vivo. PMID- 9368144 TI - Human osteoblast-like cells (MG63) proliferate on a bioactive glass surface. AB - Bioglass, a resorbable glass, previously has been evaluated as a bone graft substitute using cells of animal origin. Limited information is available on its effect on human cells. The objective of this study was to test the hypothesis that Bioglass supports viability and proliferation of human bone cells. As a prototype of human bone cells, the osteoblast cell line MG63 was used and propagated on Bioglass disks. MG63 cells also were seeded onto disks made of titanium (Ti-6Al-4V) and of cobalt chrome (Co-Cr-Mo) alloys. The number of viable cells recovered was similar for Bioglass, titanium, and polystyrene control surfaces. Significantly fewer cells were recovered from CoCr (P < 0.05) compared to Bioglass, Ti-6 Al-4v, and polystyrene surfaces. The proportion of cells undergoing DNA synthesis, estimated by thymidine uptake, was significantly greater on Bioglass and titanium surfaces (P < 0.05) than on the CoCr surface. There were detectable differences in cell morphology on these biomaterials. Functional capacity was tested by assay of osteocalcin production and no differences were detectable among the different biomaterials. This study supports the hypothesis that 45S5 Bioglass provides a favorable environment for human osteoblast proliferation and function. Bioglass may have clinical potential as a bone graft substitute, a bioactive grout, or an implant coating for promoting bony ingrowth in uncemented prostheses. PMID- 9368145 TI - Engineering the tissue which encapsulates subcutaneous implants. I. Diffusion properties. AB - This report uses normal rat subcutis as a reference point to provide a quantitative analysis of small analyte transport through the tissue which encapsulates implants. Polyvinyl alcohol (PVA) with 60- and 350-micron mean pore size (PVA-60, PVA-350), nonporous PVA (PVA-skin), and stainless-steel cage (SS) specimens were implanted in the subcutis of Sprague-Dawley rats for 4 weeks to elicit a range of capsular wound-healing tissues. Histologic examination showed that the capsular tissue which formed around PVA-skin and SS specimens was densely fibrous and avascular. That forming around PVA-60 and PVA-350 was less densely fibrous and more vascular. The fibrous content of capsular tissue and subcutis was determined from eosin-stained histologic sections. Dual-chamber diffusion measurements of sodium fluorescein (Mw 376 g/mol) through capsular tissue and normal rat subcutis were used to quantitatively compare the effective diffusion coefficients of small analytes on the order of glucose. The two most fibrous capsular tissues exhibited diffusion coefficients that were statistically (p < 0.05) less than that determined for rat subcutis by 50 and 25% for PVA-skin and SS, respectively. The diffusion coefficients of the less dense capsular tissue which formed around the porous implants were not statistically different from subcutis. The experimentally measured diffusion coefficients of the two most fibrous capsular tissues were closely predicted by a simple two-component diffusion model consisting of an aqueous interstitium with an array of impenetrable bodies equal in volume fraction to the fibrous content of the tissue. This model overestimates the diffusion coefficients measured for the least fibrous tissues. Using the diffusion coefficient measured for the PVA-skin capsular tissue, a finite difference model predicts that a 200-microns-thick capsular layer would increase from 5 to 20 min the time required for subcutaneously implanted sensor to detect 95% of the blood analyte concentration. This study suggests that the fibrous capsule forming around a subcutaneously implanted smooth-surface sensor imposes a significant diffusion barrier to small analytes such as glucose, thus increasing the lag time of the sensor by as much as threefold. A corollary observation is that a sensor with a porous surface which allows tissue ingrowth may be more responsive to blood analyte fluctuations as a result of its a more vascular and less fibrous encapsulation tissue. PMID- 9368146 TI - Long-term engraftment of hepatocytes transplanted on biodegradable polymer sponges. AB - Hepatocyte transplantation may provide an alternative to orthotopic liver transplantation to treat liver failure. However, suitable systems to transplant hepatocytes and promote long-term engraftment must be developed. In this study, highly porous, biodegradable sponges were fabricated from poly (L-lactic acid) (PLA), and poly (DL-lacticco-glycolic acid) (PLGA), and utilized to transplant hepatocytes into the mesentery of three groups of Lewis rats. The portal vein was shunted to the inferior vena cava in one group of rats (PCS). The second group of animals received a PCS and a 70% hepatectomy on the day of sponge-hepatocyte implantation (PCS + HEP), and the control group (CON) received no surgical stimulation. The sponges were vascularized by ingrowth of fibrovascular tissue over the first 7 days in vivo. Approximately 95-99% of the implanted hepatocytes (determined utilizing computer-assisted image analysis) died in all three experimental groups during this time. The number of engrafted hepatocytes in the CON group further decreased over the next 7 days to 1.3 +/- 1.1% of the original cell number. However, the number of engrafted hepatocytes in the PCS and PCS + HEP increased over this time to 6 +/- 1% and 5 +/- 2%, respectively. The number of engrafted hepatocytes in the PCS group continued to increase over the next 2.5 months to a value of 26 +/- 12% of the initial cell number, and a large number of engrafted hepatocytes was still present at 6 months. These results indicate that stable new tissues can be engineered by transplanting hepatocytes on biodegradable sponges into heterotopic locations if appropriate stimulation is provided. PMID- 9368147 TI - Electrochemical response of CoCrMo to high-speed fracture of its metal oxide using an electrochemical scratch test method. AB - A new test method was used to rapidly produce a controlled, repeatable scratch on the surface of CoCrMo (ASTM F75) samples, resulting in fracture of the surface oxide. Current transients resulting from ionic dissolution and repassivation of the exposed reactive alloy were measured with the samples potentiostatically held in phosphate-buffered saline. The effects of potential, contact load, pH, aeration, and proteins on the magnitude of the current transients and time constants for repassivation were determined. Using the scratch test apparatus, topographic images of scratched surfaces were constructed and used to measure scratch depth. Aeration had no significant effect on peak currents and time constants owing to the availability of oxygen from the hydrolysis of water. Peak current behavior reflected the transition regions observed in polarization curves. A decrease in peak currents in the presence of albumin may have been due to barrier effects of the adsorbed protein preventing water from reaching the sample surface, or lubrication resulting in less material removed from the surface during scratching. Peak currents and scratch depth increased with load. A model used to predict repassivation behavior was in agreement with experimental results. PMID- 9368148 TI - Mineral trioxide aggregate stimulates a biological response in human osteoblasts. AB - We report a novel material that appears to stimulate cytokine production in human osteoblasts and allow good adherence of the cells to the material. We have examined cultured osteoblasts (MG-63) in the presence of mineral trioxide aggregate (MTA) as set in moist conditions; secondly, we examined the behavior of these MG-63 cells with respect to cytokine and osteocalcin production and alkaline phosphatase activity. Standard ELISA assays were used for assessment of interleukin (IL)-1 alpha, IL-1 beta, IL-6, macrophage colony stimulating factor (M-CSF), and osteocalcin. Furthermore the levels of alkaline phosphatase were measured to establish the level of differentiation of the cells. Cells without MTA served as controls. Cells also were grown in the presence of polymethylmethacrylate (PMA), the commonly used orthopedic cement. In all dishes cells were seen adhering to the base and MTA at 6 h and had increased to confluence at 144 h. IL-1 alpha (175.1 +/- 32.6 pg/mL), IL-1 beta (154.0 +/- 26.7 pg/mL), and IL-6 (214.7 +/- 21.8 pg/mL) were raised when the cells were grown in the presence of MTA at 144 h, with raised values at all time intervals. M-CSF appeared to be unaffected although the overall value was high (7,045.0 +/- 89.5 pg/mL). In contrast, cells grown in the absence of MTA produced negligible amounts of these cytokines (< pg/mL) as did those cells grown in the presence of PMA. Osteocalcin production increased when cells were grown on MTA from 3.8 +/- 0.87 ng/mL to 19.7 +/- 2.8 ng/mL. No osteocalcin could be detected with PMA. Cells in contact with MTA also appeared to have levels of alkaline phosphatase similar to those reported elsewhere (4.3 +/- 0.21 mumol/mg protein/min). No cells could be found attached to PMA and so no alkaline phosphatase activity could be measured. PMID- 9368149 TI - Surface reaction layer formation in vitro on a bioactive glass fiber/polymeric composite. AB - In order to provide a fixation vehicle between a polymeric composite femoral hip prosthesis and bone tissue, we fabricated bioactive glass fibers. The glass fibers had a tensile strength of 596 MPa, 14 times that of bulk bioactive glass. After immersion in protein-free simulated body fluid for 10 days, we observed the development of a calcium phosphate layer (specifically, partially crystallized, calcium-deficient carbonated hydroxyapatite) on the surface of the glass fibers. The stages of the surface reaction layer formation were similar to those of 45S5 bioactive glass although the kinetics of the reaction layer formation were slower. We combined the bioactive glass fibers with a polymeric matrix to form a fiber-reinforced composite material and observed the formation of a calcium phosphate layer on the surface of the glass fibers within the composite material after immersion in both protein-free and protein-containing simulated body fluids. The rate of reaction layer formation was reduced in the presence of proteins. In both protein-free and protein-containing solutions, a "halo" of bioactivity reactions was observed on the surface of the polymer in regions surrounding the glass fibers. Our results suggest these glass fibers and glass fiber composites will exhibit bioactivity reactions in vivo. PMID- 9368150 TI - Outcomes and specialty care. PMID- 9368151 TI - In tune with the father of phacoemulsification. PMID- 9368152 TI - Penetrating keratoplasty for keratoconus? PMID- 9368153 TI - Horizontal corneal diameter and its implications for implanting sulcus-fixated lenses. PMID- 9368154 TI - Consultation section. Cataract surgical problem. PMID- 9368155 TI - One-handed phacoemulsification with low settings. AB - We describe a technique in which one-handed phacoemulsification with low aspiration flow and vacuum is performed with a peristaltic pump machine. With this technique, ultrasonic energy can be used for nucleus segmentation without the need for a second instrument. Measurements in cadaver eyes and clinical experience showed the technique to be simple, effective, and safe. PMID- 9368156 TI - Phacoemulsification with a bevel-down phaco tip: phaco-drill. AB - We present a technique for in situ lens nucleus emulsification using low phaco power and high vacuum, a continuous curvilinear capsulorhexis, and hydrodelineation. Emulsification is done with the phaco tip slanted down 30 or 45 degrees. Cutting and aspiration do not cause an undesirable energy loss. This technique can be combined with the nuclear chopping or divide and conquer methods because of its ability to drill and hold the nucleus. Posterior capsular rupture is prevented because the separated epinucleus acts as a barrier between the nucleus and the cortex. The low power used minimizes the energy transfer to the corneal endothelium. This technique is particularly useful in eyes with brunescent cataract. PMID- 9368157 TI - Alcohol versus mechanical epithelial debridement: effect on underlying cornea before excimer laser surgery. AB - PURPOSE: To determine the effects of 70% isopropyl alcohol used for corneal debridement on surface smoothness, stromal keratocytes, and ease of epithelial removal. SETTING: Cornea Research Laboratory, University of Rochester, and Excimer Laser Laboratory, Genesee Valley Eye Institute, Rochester, New York, USA. METHODS: Rabbit corneas were de-epithelialized mechanically or with 70% alcohol. The rabbits were split into groups and evaluated immediately or after a 50 microns deep excimer laser phototherapeutic keratectomy. All tissue was evaluated and compared in terms of surface smoothness parameters, loss of keratocytes, and inflammatory response to de-epithelialization. RESULTS: Computerized laser interferometric microscopy showed no between-group difference in the surface smoothness parameters. There was a marked absence of keratocytes in the superficial 25% of the corneal stroma. The loss of keratocytes was significantly higher (P < .001) in corneas treated with isopropyl alcohol. The inflammatory response 24 hours after epithelial removal was significantly higher (P < .001) in the corneas treated with alcohol. CONCLUSION: The use of 70% isopropyl alcohol applied for 2 minutes for epithelial removal did not enhance the quality of the subsequent excimer laser procedure. In contrast, isopropyl alcohol increased the inflammatory response, and it may have damaging effects on keratocytes. We would not advocate the use of 70% isopropyl alcohol as administered in our study to remove corneal epithelium before excimer laser surgery. PMID- 9368158 TI - Alcohol removal of the epithelium for excimer laser ablation: outcomes analysis. AB - PURPOSE: To determine whether removing the corneal epithelium by dilute alcohol is equal to other epithelial removal techniques. SETTING: The Bochner Eye Institute, Toronto, Ontario, Canada. METHODS: Epithelium was removed using 25% alcohol placed on a circular pledget; the alcohol remained on the cornea for 3 minutes. Irrigation was performed with cold balanced salt solution. The epithelium was then lifted with forceps and removed. Ninety-one eyes having photorefractive keratectomy for low myopia (less than 8.00 diopters) were treated; 41 eyes were followed between 4 and 10 months (mean 6 months). Complications such as haze and loss of best corrected visual acuity (BCVA) were recorded. RESULTS: All alcohol-treated eyes achieved a BCVA of 20/40 or better, 65.9% had 20/20 and 92.7%, 20/25 or better. There were no complications or adverse effects. CONCLUSIONS: Epithelial removal using 25% alcohol did not adversely affect the algorithms used with the VISX 20/20 excimer laser, indicating the technique is safe, predictable, and effective. There was no significant loss of BCVA, toxic effects, or stromal hydration. PMID- 9368159 TI - Prospective, randomized vector analysis of astigmatism after three-, one-, and no suture phacoemulsification. AB - PURPOSE: To compare surgically induced astigmatism and visual outcomes after three-, one-, and no-suture phacoemulsification. SETTING: Johns Hopkins Hospital, Baltimore, Maryland and Manhattan Eye, Ear, and Throat Hospital, New York, New York, USA. METHODS: This prospective, randomized study followed 131 patients treated with phacoemulsification with a 5.5 mm self-sealing scleral tunnel and implantation of a 5.5 mm poly(methyl methacrylate) posterior chamber lens. Radial 10-0 nylon sutures were used in the three- and one-suture groups. RESULTS: Mean astigmatism was greatest in the first postoperative week in all groups and stabilized after 8 weeks. The percentage of patients with with-the-rule (WTR) astigmatism increased from baseline in the one- and three-suture groups and decreased in the sutureless group. Mean uncorrected Snellen acuity was significantly better in the no- and one-suture groups than in the three-suture group at 1 week. There were no significant differences in uncorrected acuity at other times. No statistically significant differences in the surgically induced spherical equivalent were noted among the three groups during the 1 year follow up. There was significantly less surgically induced keratometric astigmatism in the one-suture group at 4 (P = .03) and 8 (P = .007) weeks postoperatively. At all follow-ups, the sutureless group had the greatest proportion of patients, with significant ATR astigmatic shift (1 week, 17%; 4 weeks, 32%); and the lowest proportion of patients with significant WTR astigmatic shift (10% after 1 week). At 4 weeks, the percentage of patients with significant WTR shift in the one suture group dropped to that in the sutureless group (10%); however, those in the one-suture group had less ATR astigmatic shift (16%). CONCLUSION: Sutureless and one-suture surgery resulted in a low percentage of WTR induced astigmatism 4 weeks postoperatively. Compared with sutureless surgery, the one-suture surgery resulted in less ATR shift. PMID- 9368160 TI - Complications of excimer laser photorefractive keratectomy for myopia. AB - PURPOSE: To evaluate the safety and complication rates of excimer laser photorefractive keratectomy (PRK). SETTING: Assutah Laser Center, Tel-Aviv, Israel. METHODS: This retrospective study evaluated the complication rate after PRK in 825 consecutive patients who had PRK for myopia and had a follow-up of at least 12 months. RESULTS: At 12 months postoperatively, 4.0% of patients suffered from overcorrection and 8.6% from undercorrection. Induced astigmatism developed in 1.4% of all operated eyes. Three percent of the patients had haze, and 3.6% reported glare or halos. Twenty-three eyes (2.7%) lost one line or more of best corrected visual acuity (BCVA). Ptosis developed in 0.4% of the eyes, and 3.5% had a significant increase in intraocular pressure resulting from corticosteroid treatment. There were no complications in 678 eyes (82.5%). CONCLUSION: Eighty two percent of eyes having PRK did not develop complications. In 18.0% one or more complication, mainly undercorrection, overcorrection, or loss of BCVA, occurred. PMID- 9368161 TI - Occurrence of retained lens fragments after phacoemulsification in The Netherlands. AB - PURPOSE: To determine the incidence of retained lens fragments after phacoemulsification in The Netherlands and to evaluate the effect of vitrectomy on this complication. SETTING: Eleven vitreoretinal centers in The Netherlands. METHODS: We performed a retrospective analysis of all patients with retained lens fragments (N = 70) who were referred for vitreoretinal surgery to 11 specialized centers. Seven patients (10%) were treated with medication alone, and 63 (90%) had pars plana vitrectomy. Minimum follow-up after vitrectomy was 3 months. RESULTS: The incidence of retained lens fragments in The Netherlands was calculated at 0.9/1000 cataract operations. Retained lens fragments occurred during the learning curve and with experienced surgeons. After medical or surgical treatment, visual acuity was 20/40 or better in 43 of 70 patients (61%). Uveitis disappeared in all cases. Retinal detachment occurred in 10 patients (14%). Attached retinal breaks were treated in an additional 5 patients. Corneal grafting was performed in 2 patients. Patients who had immediate vitrectomy did not have better functional results than patients in whom vitrectomy was delayed. The iris-fixated claw lens was implanted successfully when capsular support was insufficient. CONCLUSIONS: The introduction of phacoemulsification in The Netherlands is associated with an increase of patients with retained lens fragments. Retained lens fragments are complicated by an increased risk for retinal detachment and corneal decompensation. Vitrectomy resulted in a marked improvement of visual acuity and clearing of uveitis. PMID- 9368163 TI - Induced astigmatism after near-clear hinge incision. AB - PURPOSE: To evaluate astigmatism induced by the near-clear hinge incision. SETTING: Casa di Cura Villa Toniolo, Bologna, and Day Hospital Nuova Ricerca, Rimini, Italy. METHODS: The results in 100 eyes having phacoemulsification with a 3.2 or 4.1 mm temporal near-clear hinge incision were evaluated for a maximum of 6 months. Corneal curvature was measured using computerized videokeratography, and surgically induced astigmatism was computed by vector analysis. Surgically induced corneal topographic changes were also evaluated. RESULTS: Mean induced cylinder in the 3.2 mm incision group was 0.4 diopter (D) +/- 0.2 (SD) 6 months after surgery; there was no significant difference in the values at 4 days and 6 months. Mean induced cylinder in the 4.1 mm incision group was similar at 1 and 6 months (0.47 and 0.45 D, respectively). However, it was significantly higher at 4 days (0.56 D). Vector decomposition analysis showed that the with-the-rule component was prevalent and remained constant over 6 months. Topographic analysis showed localized wound-related flattening with minimal central corneal changes. CONCLUSION: The near-clear hinge incision was almost astigmatically neutral and resulted in self-sealing incisions that did not leak. PMID- 9368162 TI - Efficacy of diclofenac eyedrops in preventing postoperative inflammation and long term cystoid macular edema. Italian Diclofenac Study Group. AB - PURPOSE: To compare the efficacy and tolerance of diclofenac 0.1% eyedrops with a regimen that included a brief course of steroids in the treatment of postoperative inflammation after extracapsular cataract surgery and posterior chamber intraocular lens implantation. A second objective was to compare the efficacy of diclofenac 0.1% eyedrops in the same patients and control group in preventing cystoid macular edema (CME). SETTING: Eight university/hospital centers and one company in Italy. METHODS: The multicenter, controlled, randomized, prospective, double-blind study included 281 patients. All were evaluated at baseline, at surgery, and after 1, 5, 36, 67, and 140 days. Postoperative inflammation was measured by the clinical assessment of inflammation: conjunctival hyperemia, ciliary flush, Tyndall effect, and cells in the anterior chamber. Fluorescein angiography was performed to evaluate the presence/absence of CME before surgery and after 36 and 140 days. RESULTS: During follow-up, no differences in intraoperative pressure were observed within or between groups or between operated and fellow eyes. No statistically significant between-group differences in postoperative inflammation were found. After 36 days, angiographic CME was found in 9 patients (6.43%) in the diclofenac group and 20 (15.15%) in the control group (P = .033) with a relative risk for developing CME of 0.40 (CI95 0.19 to 0.84). At the end of follow-up, it was found in 4 patients in the diclofenac group (3.31%) and 10 (9.26%) in the control group (P = .05) with a relative risk of 0.36 (CI95 0.12 to 0.90). CONCLUSION: Diclofenac sodium was as effective as the control regimen in controlling postoperative inflammation after cataract surgery. It also had a protective effect on the development of angiographic CME after 36 and 140 days. PMID- 9368164 TI - Effect of nylon suture diameter on induced astigmatism after phacoemulsification. AB - PURPOSE: To prospectively compare the clinical results of 10-0 and 9-0 monofilament nylon sutures after phacoemulsification with poly(methyl methacrylate) intraocular lens implantation through a 4.0 mm cruciate incision. SETTING: Department of Ophthalmology, Ramon y Cajal Hospital, Madrid, Spain. METHODS: One hundred eyes with cataract were randomly assigned to have surgery using a 10-0 or a 9-0 nylon suture. Except for suture diameter, identical surgical methods were used in every case. Data on uncorrected visual acuity, keratometry and postoperative astigmatism were analyzed up to 12 months after surgery. RESULTS: Both groups had similar uncorrected visual acuity. Mean postoperative corneal astigmatism was against the rule in the 10-0 nylon suture group and with the rule in the 9-0 nylon suture group. Significant differences were found between groups (P < .05). CONCLUSION: Both suture diameters offered satisfactory clinical results. Patients with preoperative with-the-rule astigmatism might benefit from 10-0 nylon sutures and those with preoperative against-the-rule astigmatism, from 9-0 nylon sutures. PMID- 9368165 TI - Intraocular lens power formula based on vergence calculation and lens design. AB - PURPOSE: To present a new method of intraocular lens (IOL) power calculation that takes into account the power-dependent variation in lens design. SETTING: Department of Ophthalmology, Aalborg, Denmark. METHODS: Information on exact IOL design is derived from the manufacturers' cutting cards. These data were built into an IOL calculation formula based on exact ray tracing and vergence calculation. All algorithms are demonstrated. RESULTS: The method is optically correct as all refractive surfaces are characterized with respect to both position and refractive power. In simulation models, the Naeser and the Holladay formulas performed similarly, while the SRK/T formula predicted higher postoperative refractions for low-power IOLs. CONCLUSION: It is possible to incorporate the exact IOL design into an IOL power calculation formula. Theoretically, the Naeser formula should increase the accuracy of IOL power calculation; however, this has yet to be proved from empirical data. The formula provides an advantage in analysis of postoperative pseudophakia for experimental/scientific purposes because all intraocular distances and powers may be measured or calculated. PMID- 9368166 TI - Intraocular lens power calculation for microphthalmos. AB - PURPOSE: To evaluate the refractive results and accuracy of intraocular lens (IOL) power calculation formulas in eyes with microphthalmos. SETTING: Department of Ophthalmology, Showa University Hospital, Tokyo, Japan. METHODS: The accuracy of IOL power calculated using the SRK, SRK II, S-SRK, SRK/T, Holladay, and Hoffer Q formulas was evaluated in six eyes with axial lengths less than 19.0 mm. RESULTS: Postoperative measurement of refraction showed a tendency toward hypermetropia compared with the refraction predicted by each formula. The best predicted refraction was calculated using the SRK/T formula. The tendency for hyperopic estimation was related to the axial length, particularly in eyes with a shorter axial length. However, there was no relationship between the refractive power of the cornea and the error in the predicted refraction by the SRK/T formula. Two eyes with an IOL power of 30.0 diopters (D) had severe hypermetropia. CONCLUSION: Theoretical formulas were more accurate than empirical ones in eyes with microphthalmos. The severe hypermetropia in the two eyes with a 30.0 D IOL indicates that such patients require a higher IOL power. PMID- 9368167 TI - Comparison of portable automated keratometry and manual keratometry for IOL calculation. AB - PURPOSE: To compare the accuracy of portable automated keratometry (PAK) with that of manual keratometry (MK) in measuring corneal power for intraocular lens calculations. SETTING: Wilford Hall Medical Center, San Antonio, Texas, USA. METHODS: In Part 1 of the study, five ophthalmic technicians performed keratometric analysis in 20 eyes in 10 volunteers using both manual and automated methods to determine the relative accuracy and reproducibility of each instrument. In Part 2, both MK and PAK were prospectively performed in 11 patients having cataract surgery to compare the accuracy of each instrument in predicting postoperative refractive outcome. RESULTS: The difference between instruments in determining the average corneal power in all eyes was less than 0.10 diopter (D) (MK = 43.84 D, PAK = 43.93 D). Portable keratometry demonstrated less variability in measurements in each eye (average standard deviation, MK = 0.30 D, PAK = 0.11 D; average range, MK = 1.08 D, PAK = 0.44 D). The mean absolute refractive error (difference between the actual refractive outcome and predicted refractive outcome) was 0.37 D +/- 0.30 (SD) using MK values and 0.45 +/- 0.19 D using PAK values. CONCLUSIONS: Portable automated keratometry is a simple keratometric technique that appeared to be as accurate as but with less variability than manual keratometry in determining corneal power for cataract surgery. PMID- 9368168 TI - Change in postoperative refractive error when vitrectomy is added to intraocular lens implantation. AB - PURPOSE: To compare the actual and expected refractive errors after intraocular lens (IOL) implantation alone with those after IOL implantation with simultaneous vitrectomy. SETTING: Shinjo Eye Clinic, Miyazaki, Japan. METHOD: One hundred thirty-six eyes had cataract extraction and implantation of a single-piece IOL using a frown incision, continuous annular anterior capsule tear, phacoemulsification, and intracapsular lens fixation. Thirty-six eyes also had vitrectomy. RESULTS: Mean postoperative refractive error was 0.55 diopter (D) +/- 1.34 (SD) in eyes having no vitrectomy and 0.04 +/- 1.24 D in those having vitrectomy. The difference between groups was statistically significant (P = .047; t-test). CONCLUSION: The refraction after simultaneous IOL implantation and vitrectomy shifted toward myopia by a mean of 0.50 D compared with that after IOL implantation alone. PMID- 9368170 TI - Catquest questionnaire for use in cataract surgery care: description, validity, and reliability. AB - PURPOSE: To describe and evaluate the Catquest self-assessment questionnaire for cataract patients. SETTING: Thirty-five Swedish departments of ophthalmology. METHODS: The Catquest is designed to be used by cataract surgeons for continuous quality control regarding appropriateness and outcome of surgery. It is administered before and after cataract surgery. The questionnaire focuses on visual disabilities in daily life, activity level, cataract symptoms, and degree of independence. The results are interpreted using a benefit matrix that credits not only a decrease in visual disabilities and cataract symptoms but also an improvement or a maintenance of a preoperative activity level. The questionnaire was used by consecutive patients having surgery during March 1995 at the participating surgical units. RESULTS: A full range of responses was given to all questions. A strong relationship was found between patients' responses to questions about visual disabilities in daily life and their general opinion about vision (P < .001). The answers showed a high stability when test-retest reliability was evaluated and a high internal consistency when different questions about visual disabilities were compared (P < .001). The answers from cataract patients before surgery were significantly different from those of a control group that did not have cataract (P < .0001). CONCLUSION: The Catquest had high validity and reliability when used as a disease-specific instrument testing visual disabilities in patients having cataract extraction. PMID- 9368169 TI - HsS versus a balanced salt solution as a corneal wetting agent during routine cataract extraction and lens implantation. AB - PURPOSE: To evaluate HsS (elastoviscous hylan surgical shield, 0.45%) as an alternative to repeated corneal irrigation with a balanced salt solution during cataract surgery. SETTING: York Finch General Hospital, Toronto, Ontario (Center A), and Centre Hospitalier de St. Laurent, St. Laurent, Quebec (Center B), Canada. METHODS: This dual-center, randomized, prospective clinical trial comprised 60 patients (40 at Center A; 20 at Center B) who had routine small incision cataract surgery (Center A, endolenticular phacoemulsification; Center B, Khoury manual phacofragmentation) with in-the-bag implantation of a posterior chamber intraocular lens. The corneal irrigating fluid was randomly assigned to be HsS or a balanced salt solution. The frequency of required applications, duration of efficacy of each application, and assessment of corneal moisture, clarity, transparency, and reflection in the HsS and balanced salt solution groups were recorded and compared. RESULTS: Mean frequency of applications was 13.9 per procedure in the balanced salt solution group and 1.3 per procedure in the HsS group (P = .0001). Mean duration of effectiveness per application was 23.4 minutes for HsS and 2.0 minutes for balanced salt solution (P = .0001). No significant differences in safety or effect on corneal health were observed between the two solutions. CONCLUSION: The HsS was significantly more effective than a balanced salt solution in maintaining corneal moisture, clarity, and transparency. The use of HsS may be a safer, more effective option in ophthalmic surgery because it minimizes the obstructed visualization of the surgical field caused by frequent corneal irrigation and loss of surgeon concentration. PMID- 9368171 TI - Compression forces of haptics of selected posterior chamber lenses. AB - PURPOSE: To compare the compressive forces of the haptics of different intraocular lens (IOL) models and analyze the observed differences. SETTING: Central Hospital of Central Finland and University of Jyvaskyla, Jyvaskyla, Finland. METHODS: The haptics of 28 IOL models were compressed to a diameter of 9.0 mm. The compression forces were measured at 0.5 mm intervals. The conclusions were verified by numerical simulations of mechanical models of the lenses. RESULTS: The measured forces varied between 100 and 601 mg at a diameter of 11.0 mm, 206 and 1057 mg at a diameter of 10.0 mm, and 315 and 2094 mg at a diameter of 9.0 mm. The slopes of the force curves of the three-piece lenses were fairly linear. In general, the three-piece models were less rigid than one-piece models and underwent plastic deformations after repeated compressions. For most one piece models, compression force increased progressively with increasing compression. The overall IOL diameter and differences in haptic thickness and length and the angle between optic at the point of haptic insertion were the main causes of the observed differences in the compression forces. The variation in forces between individual specimens of the same model, which occurred with almost all models, were mainly the result of variations in haptic thickness. CONCLUSION: Great variations in the compression forces of the IOL haptics were found. Compression behaviors should be taken into account when selecting a lens to implant. PMID- 9368172 TI - Centration of intraocular lenses with circular haptics. AB - PURPOSE: To evaluate two intraocular lens (IOL) models with a circular haptic configuration designed to better distribute forces within the capsular bag over 360 degrees. SETTING: University and Maria Middelares hospitals, Antwerp, Belgium. METHODS: Two IOLs with circular haptics were evaluated for 6 months after implantation: a one-piece, all-poly(methyl methacrylate) (PMMA), Corneal IS M 5.5 lens with a 5.5 mm biconvex optic, overall diameter of 9.8 mm, and two semicircular open haptics (n = 103); a plano-convex, all-PMMA, modified Anis lens with a 5.5 mm plano-convex optic, total diameter of 10.0 or 11.0 mm (depending on diopter), and closed-loop haptics (n = 335). All lenses were inserted through a 5.5 mm scleral incision after phacoemulsification and placed in the capsular bag through a 4.5 mm curvilinear capsulorhexis. The IOLs centered without being rotated. RESULTS: Six months after implantation, the IOL optics were well centered, even in eyes with an eccentric capsulorhexis (19%). In two eyes with partial zonulysis and in seven with posterior capsule rupture, decentration of less than 0.5 mm was observed. Both lenses provided uniform capsular support without causing stress lines in the posterior capsule. There were no cases of capsule contraction syndrome. Posterior capsule fibrosis reducing visual acuity occurred in 4% of eyes in both series. CONCLUSION: The Corneal IS M 5.5 and the Anis lens with circular haptics prevented late optic decentration and, therefore, would be useful in cases of eccentric capsulorhexis, partial zonulysis, anterior radial tears, and posterior capsule rupture. These IOLs may also prevent capsular contraction. PMID- 9368173 TI - Morphologic compatibility or intraocular lens haptics and the lens capsule. AB - PURPOSE: To evaluate the mechanical relationship between the intraocular lens (IOL) haptic and the capsular bag by quantitatively analyzing the fit of the haptic with the capsule equator and the capsular bag deformity induced by the implanted lens haptics. SETTING: Division of Morphogenesis, Department of Developmental Biology, National Institute for Basic Biology, Okazaki, Japan. METHODS: Following implantation of a poly(methyl methacrylate)(PMMA) ring in three excised human capsular bags with continuous curvilinear capsulorhexis (CCC), IOLs with different overall lengths or haptic designs were implanted in the bags and photographed. The straight length of the area of contact between the haptic and the capsule equator on the photographs was measured to provide a quantitative index of in-the-bag fixation and the length from the external margin of the PMMA ring to the external margin of the loop along the maximal diameter of the capsular bag, to indicate the quantitative degree of capsular deformity induced by an IOL. RESULTS: An IOL with modified-C loops produced better fit along the capsule equator and less deformity than an IOL with modified-J loops, and an IOL with an overall length of 12.0 or 12.5 mm produced a sufficiently good fit and less distortion of the capsular bag than an IOL with an overall length over 13.0 mm. CONCLUSION: An IOL with modified-C loops and an overall length of 12.0 or 12.5 mm is adequate for in-the-bag implantation following CCC. PMID- 9368174 TI - Reduced intraocular pressure after phacoemulsification and posterior chamber intraocular lens implantation. AB - PURPOSE: To ascertain whether phacoemulsification with posterior chamber intraocular lens (IOL) implantation causes long-term reduction in intraocular pressure (IOP). SETTING: Private practice, Kempten, Germany. METHODS: Intraocular pressure was measured in both eyes of 120 consecutive patients who were unilaterally phakic after phacoemulsification a mean of 17 months +/- 17 (SD) previously. Mean age of the 36 men and 84 women was 76 +/- 10 years. Data were analyzed using binomial distribution and the Wilcoxon signed-rank test. RESULTS: The median ratio of IOP in the pseudophakic eye to IOP in the phakic eye was 0.83. The IOP was lower in the pseudophakic eye in 96 patients (80%). The median IOP was 12 mm Hg in the pseudophakic eyes and 14 mm Hg in the phakic eyes (P < .001). As measured by the interquartile range, IOP distribution was more centered in the pseudophakic than in the phakic eyes (3 versus 4). The IOP in the pseudophakic eyes remained lower to the last measurement, 5 years postoperatively, and appeared to be independent of patient age. Lower IOP in the pseudophakic eye was consistently present in patients with higher IOP in the phakic eye (16 to 22 mm Hg). CONCLUSION: Phacoemulsification with posterior chamber IOL implantation reduced IOP in most but not all patients with a preoperative IOP of 22 mm Hg or less. This reduction was maintained over several years, with the cause yet to be established. Lower IOP may decrease the risk of subsequent glaucomatous nerve damage in these patients. PMID- 9368175 TI - Membrane formation and cellular response on the surface of lenses implanted in rabbit eyes. AB - PURPOSE: To study the pathogenesis of membrane formation and cellular response on the surface of posterior chamber intraocular lenses (IOLs) implanted in rabbits. SETTING: Department of Histology and Embryology, Pathology, Ophthalmology. The First Military Medical University, Guangzhou, P.R. China. METHODS: Thirty rabbits had extracapsular lens extraction and posterior chamber IOL implantation. The IOLs were removed 4, 7, 15, 30, and 90 days postoperatively. Membrane formation and cellular response on IOL surfaces were evaluated using light (n = 25), transmission (n = 5), and scanning electron (n = 5) microscopy. RESULTS: On 30 IOLs, the incidence of cellular adhesion was 100%. Cellular components comprised macrophages, fibroblast-like cells, epithelioid cells, giant cells, ultralarge giant cells, and lymphocytes. A thin, proteinaceous film was also seen on the surface of the IOLs. The membrane of the IOL surface comprised fibrin, collagen fibrils, macrophages, fibroblast-like cells, giant cells, and fibroblasts. CONCLUSION: The findings of this study might apply to humans because cellular elements and membranes have been reported in humans. PMID- 9368176 TI - Delayed-onset Pseudomonas keratitis after radial keratotomy. AB - A 62-year-old man had nonsimultaneous, four-incision radial and astigmatic keratotomy in both eyes. Both surgeries were uneventful. Twenty-one months later, the patient developed a corneal ulcer within one of the radial incisions in the left eye. Cultures were positive for Pseudomonas. Although Pseudomonas infections in post-RK eyes have been reported, late-onset Pseudomonas keratitis in a patient with four radial incisions and no history of contact lens wear is contrary to previous reports. PMID- 9368177 TI - Focal corneal decompensation caused by an anterior capsulotomy remnant. AB - Capsule contraction syndrome, an infrequent but sight-compromising condition, can usually be managed by a neodymium:YAG (Nd:YAG) anterior capsulotomy. The anterior capsule can be split from the visual axis to the periphery with multiple spokes. In this patient, however, these spokes closed, leaving the small anterior capsulotomy indistinguishable from its pre-capsulotomy appearance. A subsequent Nd:YAG laser circumcision of the thickened capsulotomy margin restored the patient's sight. The excised capsular doughnut fell into the anterior chamber angle and resulted 34 months later in localized corneal decompensation. Removal of the capsular remnant markedly improved the corneal changes. The experience from this case suggests that multiple Nd:YAG relaxing incisions may be a safer way to manage capsule contraction syndrome than complete circumcision of the anterior capsule. If the latter approach is taken, the capsular remnant should not be cut completely free of the anterior capsule. PMID- 9368178 TI - ISHAGE: the next step. International Society for Hematotherapy and Graft Engineering. PMID- 9368179 TI - Will CD34+ standardization solve all problems related to cell therapy? PMID- 9368180 TI - Ex vivo treatment of bone marrow with phosphorothioate oligonucleotide OL(1)p53 for autologous transplantation in acute myelogenous leukemia and myelodysplastic syndrome. AB - Effective ex vivo purging techniques can decrease the likelihood of infusing bone marrow contaminated with leukemic cells during autologous transplantation. In preliminary studies, OL(1)p53, a 20-mer phosphorothioate oligonucleotide directed against p53 mRNA, decreased the number of acute myelogenous leukemia (AML) cells in vitro, suggesting a possible role for OL(1)p53 in purging bone marrow harvests of leukemia cells. To demonstrate that OL(1)p53 was nontoxic to hematopoietic progenitor cells, normal bone marrow cells were incubated with 10 microM OL(1)p53 for 36 h, and hematopoietic progenitor cell survival was determined by in vitro colony assays. OL(1)p53 had no toxic effect on the growth of either myeloid (CFU GM) or erythroid (BFU-E) progenitor cells. OL(1)p53 was then used to ex vivo purge bone marrow harvests from nine patients with either AML or myelodysplastic syndrome (MDS). Bone marrow cells were incubated with 10 microM OL(1)p53 for 36 h before transplantation. The median times posttransplantation for the patient to recover an absolute neutrophil count greater than 0.5 x 10(9)/L and a platelet transfusion independence were 30 days and 56 days, respectively. Incubation of bone marrow cells with OL(1)p53 had no detrimental effect on the growth of hematopoietic progenitor cells, and transplantation of autologous bone marrow cells treated with the phosphorothioate oligonucleotide, OL(1)p53, resulted in successful recovery of circulating neutrophils following high-dose therapy in patients with AML or MDS. The data show that OL(1)p53 can be used safely to purge autologous bone marrow harvests from patients with leukemia. PMID- 9368181 TI - Human bone marrow-derived mesenchymal (stromal) progenitor cells (MPCs) cannot be recovered from peripheral blood progenitor cell collections. AB - The purpose of this study was to compare the ability to collect human bone marrow derived mesenchymal (stromal) progenitor cells (MPC) from bone marrow versus peripheral blood hematopoietic progenitor cell (PBPC) collections using in vitro and in vivo assays. Ten milliliter samples of PBPC collections mobilized from 11 patients undergoing autotransplants using chemotherapy followed by G-CSF 5-10 micrograms/kg were evaluated using in vitro and in vivo assays for hematopoietic progenitors and MPCs. Additionally, 10 ml samples of unstimulated bone marrow aspirates as well as PBPC collected after mobilization using G-CSF 10 micrograms/kg obtained from 3 normal, histocompatible allogeneic donors were analyzed for hematopoietic progenitors and MPCs. The MPCs were isolated and culture-expanded as adherent cells in vitro and subsequently tested for the capacity to differentiate into mesenchymal phenotypes in vivo using calcium hydroxyapatite porous ceramic cubes implanted s.c. in athymic mice. Demineralized sections of these cubes were analyzed histologically for the appearance of bone and cartilage. Seven autotransplant subjects with cancer received G-CSF after chemotherapy administration, whereas 4 cancer patients and all 3 normal donors received G-CSF alone as the mobilizing regimen. For the autologous PBPC collections and the normal marrow aspirations, median hematopoietic progenitor content was in the normal range for our institution. MPCs were detected in in vitro cultures and as bone-positive ceramic cubes in samples of all 3 allogeneic donor bone marrows but in none of the 14 autologous and 6 allogeneic PBPC collections. In conclusion, MPCs could not be recovered in PBPC collections obtained from either normal donors or patients who underwent PBPC collections after mobilization therapy but could be obtained routinely from bone marrow samples. Although the role of transplanted MPCs is an area of clinical investigation, this study points out a fundamental differences in the population of cells transplanted after collection from bone marrow versus peripheral blood. PMID- 9368182 TI - A pilot study evaluating interleukin-2-activated hematopoietic stem cell transplantation for hematologic malignancies. AB - Cytotoxic effector cells are generated when autologous hematopoietic cells (HSC) are cultured with IL-2 for 24 h. Infusion of these cells followed by IL-2 administration may moderate a graft-versus tumor (GvT) effect in vivo. Sixteen patients--7 with non-Hodgkin's lymphoma (NHL), 2 with AML, 4 with multiple myeloma (MM), and 3 with Hodgkin's disease (HD)--received busulfan (4 mg/kg/day for 4 days) and cyclophosphamide (60 mg/kg/day for 2 days) or cyclophosphamide/TBI (1320 cGy). Autologous HSC were activated by culturing with IL-2 for 24 h before reinfusion. Subcutaneous administration of IL-2 began after engraftment at 1.8 x 10(6) IU/m2/day for 1-4 weeks. Neutrophil engraftment occurred on day 13.1 (median) (range 9-45 days), and platelet engraftment occurred on day 19.3 (median) (range 7-54 days) for 15 patients, with delayed engraftment observed in 3 patients. One patient experienced a fatal cardiac arrhythmia. Five patients developed transient skin rashes with histologic evaluation demonstrating findings consistent with GvHD. At 17 months (median) (range 7-23 months), 9 patients are alive, with 6 patients remaining disease free. This pilot trial demonstrates mild to moderate toxicities and a possible delay in platelet engraftment. Further trials will determine the optimal dose and duration of IL-2 therapy and possible impact of this therapy on survival. Laboratory investigations are evaluating the presence of autologous GvHD and a possible GvT effect. PMID- 9368183 TI - Large-volume leukaphereses may be more efficient than standard-volume leukaphereses for collection of peripheral blood progenitor cells. AB - To overcome the need for multiple leukaphereses to collect enough PBPC for autologous transplantation, large-volume leukaphereses (LVL) are used to process multiple blood volumes per session. We compared the efficiency of CD34+ cell collection by LVL (n = 63; median blood volumes processed 11.1) with that of standard-volume leukaphereses (SVL) (n = 38; median blood volumes processed 1.9). To achieve this in patients with different peripheral blood concentrations of CD34+ cells, we analyzed the ratio of CD34+ cells collected per unit of blood volume processed, divided by the number of CD34+ cells in total blood volume at the beginning of apheresis. For LVL, 30% (9%-323%) of circulating CD34+ cells were collected per blood volume compared with 42% (7%-144%) for SVL (p = 0.02). However, in LVL patients, peripheral blood CD34+ cells/L decreased a median of 54% during LVL (similar data for SVL not available). The number of CD34+ cells collected per blood volume processed after 4 and 8 blood volumes and at the end of LVL were 0.32 (0.01-2.05), 0.24 (0.01-1.68), and 0.22 (0.01-2.40) x 10(6) CD34+ cells/kg, respectively (p = 0.0007), despite the 54% decrease in peripheral blood CD34+ cells/L throughout LVL. A median 66% decrease in the platelet count was also observed during LVL. Thus, LVL may be more efficient than SVL for PBPC collection, allowing, in most patients, the collection in one LVL of sufficient PBPC to support autologous transplantation. PMID- 9368184 TI - Ex vivo culture of peripheral blood CD34+ cells: effects of hematopoietic growth factors on production of neutrophilic precursors. AB - A major potential application for ex vivo culture of hematopoietic progenitor cells is the treatment of cytopenia following high-dose chemotherapy and hematopoietic transplantation. We have previously postulated that infusion of a sufficient number of neutrophil postprogenitor cells generated by ex vivo culture of CD34+ cells may be able to abrogate neutropenia. In this article, we describe further development of an efficient stromal-free, cytokine-dependent, static culture system for generation of these cells. Our previous studies indicated that maximal production of nucleated cells and myeloid progenitor cells from PB CD34+ cells occurred with multiple hematopoietic growth factor (HGF), notably the 6-HGF combination of interleukin (IL)-1, IL-3, IL-6, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), and stem cell factor (SCF). In the present study, we determine the contribution of each of these 6 HGF in generation of neutrophilic precursors. SCF, G-CSF, and IL-3 were found to be the most important HGF for production of neutrophilic cells. The 4-HGF combination of IL-3, IL-6, G-CSF, and SCF was optimized by performing dose-response experiments and shown to be as potent as 6 HGF for production of nascent CFU-GM and neutrophilic precursors. PMID- 9368185 TI - The effects of the mode of delivery on the lymphocyte composition of a placental/cord blood graft. AB - The establishment of placental/cord blood as a source of clinically transplantable stem cells has been followed by the creation of a growing number of programs involved in placental/cord blood banking and storage. Placentae/umbilical cords delivered either vaginally or through elective cesarean section following an uncomplicated term pregnancy are considered acceptable as the source of a recoverable placental/cord blood unit. The effects of the mode of delivery on the lymphocyte composition of the graft have, however, not been addressed. We demonstrate significant differences in the number of lymphocytes expressing CD3, CD4, or CD56 (mature NK) cells when units obtained either following a vaginal delivery or through cesarean section are compared. We encourage the data obtained in the process of placental/cord blood transplantation to be critically evaluated with respect also to the mode of delivery. PMID- 9368187 TI - CD34+ cells can be selected efficiently from cryopreserved peripheral blood progenitor cells and can retain their proliferative potential. AB - Hematopoietic stem and progenitor cells express the CD34 antigen. Techniques have been developed that enable purified populations of CD34+ cells to be selected from hematopoietic tissues. These selected CD34+ cells have several potential applications, including CD34 selection to obtain a tumor purging effect in autologous transplantation studies and using CD34+ cells as the starting cells for ex vivo expansion studies and as a vehicle for gene transduction protocols. We have investigated the feasibility of using cryopreserved peripheral blood progenitor cells (PBPC) for CD34 selection. Cells could be recovered from cryopreservation with good yields and high viability. After CD34 selection, the final product was, on average, 84% pure, with a recovery of 54%. These cells retained extensive proliferative potential, as demonstrated by ex vivo expansion culture. We believe that cryopreserved PBPC could be thawed, and CD34+ cells could be selected and used for transplantation following high-dose chemotherapy. PMID- 9368186 TI - Optimization of purging of autologous bone marrow grafts for children with precursor B acute lymphoblastic leukemia. AB - In our laboratory, a two-step procedure is used for purging precursor B ALL from autologous bone marrow grafts of children in second bone marrow remission. An immunorosette depletion method with CD19 and CD22 MAbs is followed by one cycle of complement-mediated cell lysis with CD9 and CD10 MAbs. The aim of the present study was to determine if the efficacy of this procedure could be further enhanced by including CD20 and CD72 MAbs in the current protocol. Leukemia contaminated remission bone marrow was simulated by mixing cell line cells and normal bone marrow cells. The efficacy of purging of malignant cells was determined by culturing the cells in a limiting dilution assay. The effect of including CD20 and CD72 in the immunorosette depletion was limited. In contrast, when these MAbs were added during complement-mediated cell lysis, a significant increase in depletion of tumor cells was observed. This was true when complement lysis was carried out alone (0.4 versus 3.0 log depletion for Ros cells) and when it was preceded by immunorosette depletion (2.7 versus 4.1 log depletion for Ros cells). The loss of hematopoietic progenitor cells was not greater than with the current purging protocol. PMID- 9368188 TI - Neutrophil structural changes associated with chronic endotoxemia and lung injury. AB - Previous studies showed that chronic endotoxemia induces thickening of the alveolar wall of rabbits. The present study examines cellular changes associated with this process and attempts to define the role of PMN in this response. Rabbits received i.v. injections of either Escherichia coli lipopolysaccharide (LPS) or saline (control), 2-3 times weekly, for 28 weeks. Peripheral blood mature and immature polymorphonuclear leukocyte (PMN) cell counts were determined on Wright-stained blood smears. Lung histological analysis was performed by both light and electron microscopy. FITC-Maclura pomifera was used to identify type II cells and diaminobenzidine tetrahydrochloride-H2O2 was employed to localize peroxidase. The results show that the LPS-induced neutrophilia is associated with an increase in the circulating band cells which is consistent with active bone marrow release. PMN in the pulmonary microvessels display structural features characteristic of phagocytosis and active macromolecule synthesis. Endothelial cells, adjacent to these PMN, show numerous coated pits and large inclusions suggestive of endocytosis. The LPS-induced thickening of the alveolar wall is associated with leukocyte migration into the interstitial and alveolar spaces. Some interstitial PMN are fragmented and surrounded by dispersed elements of the connective tissue, while others appear activated and are closely associated with hyperactive fibroblasts and alveolar type II cells. The number of alveolar type II cells has increased twofold. These results show that chronic endotoxemia in rabbits causes structural changes in PMN, endothelium, interstitium, and epithelium. PMN structural changes are consistent with enhanced functional properties and their close association with modified regions of the lung parenchyma suggest that PMN play an important role in the process of this lung injury and repair. PMID- 9368189 TI - Activation of T cells via CD55: recruitment of early components of the CD3-TCR pathway is required for IL-2 secretion. AB - It was previously reported that the glycosylphosphatidylinositol (GPI)-anchored CD55 molecule provides a co-stimulatory signal for T lymphocytes and is constitutively associated with the Src-related kinase p56lck. The present studies were undertaken to clarify the mechanism of action of CD55 in T cells. We describe the failure of cross-linking of CD55 alone to induce both the elevation of the intracellular calcium concentration and the tyrosine phosphorylation of PLC-gamma in CD3+ Jurkat cells. By contrast, it is sufficient to induce the phosphorylation of tyrosine residues on p56lck, the TCR-zeta chain as well as ZAP 70. Surprisingly, the observed TCR-zeta and ZAP-70 tyrosine phosphorylations appear delayed compared to stimulation via CD3. Calcium ionophore A23187 in combination with cross-linked CD55 mAb initially caused an acceleration in the kinetic of these two phosphorylation events, followed by IL-2 secretion. Furthermore, transfection of the cytoplasmic domain of TCR-zeta in CD3- Jurkat cells, using a CD16-zeta chimera, demonstrates that CD55-mediated T-cell activation depends on the expression of this chain of the CD3-TCR complex. PMID- 9368190 TI - Analysis of the antagonist effect of IFN-alpha on IFN-gamma-induced interferon consensus sequence binding protein messenger RNA in murine macrophages. AB - Interferon consensus sequence binding protein (ICSBP), a member of the interferon regulatory factor family of DNA binding proteins, was recently demonstrated in ICSBP knockout mice to play a critical role in hematopoiesis and virus susceptibility. In macrophages, ICSBP mRNA and protein are strongly induced by IFN-gamma, but only marginally by IFN-alpha/beta. When present concurrently, IFN alpha/beta antagonizes IFN-gamma-induced ICSBP mRNA and protein synthesis. The unknown mechanism(s) underlying this antagonism may involve competitive interactions between these two IFN species or between molecules of their respective signaling cascades. The data presented demonstrate that IFN-alpha does not interfere with initiation of transmembrane signaling by IFN-gamma and that inhibition of ICSBP mRNA expression by IFN-alpha is independent of new protein synthesis. Nuclear proteins from IFN-gamma-treated or from IFN-alpha plus IFN gamma-treated cells showed identical binding patterns in EMSAs using a palindromic interferon response element (pIRE) from the ICSBP promoter. These proteins were primarily reactive with antibodies directed against STAT1 alpha and, to a lesser extent, against STAT2 and ISGF3 gamma. However, when a second, upstream IRE-like sequence was evaluated by EMSA, a DNA binding pattern distinct from that seen following exposure to IFN-gamma alone was observed after prolonged stimulation with both IFN-alpha and IFN-gamma. These data suggest a possible novel mechanism for IFN-alpha-induced inhibition of IFN-gamma-induced gene expression. PMID- 9368191 TI - An inhibitor of ornithine decarboxylase antagonizes superoxide generation by primed human polymorphonuclear leukocytes. AB - Tumor necrosis factor-alpha (TNF-alpha) induces a rapid increase in polymorphonuclear leukocyte (PMN) polyamine content which appears to be required for optimal priming of the respiratory burst. The objective of the present study was to determine whether inhibition of polyamine biosynthesis modifies PMN responses to lipopolysaccharide (LPS), granulocyte-macrophage colony-stimulating factor (GM-CSF), or granulocyte colony-stimulating factor (G-CSF). Treatment with alpha-difluoromethylornithine (DFMO), a selective inhibitor of the rate-limiting biosynthetic enzyme ornithine decarboxylase, produced dose-dependent inhibition of the respiratory burst in PMNs that were primed by these agents and subsequently activated by formyl-Met-Leu-Phe (fMLP). However, DFMO did not significantly inhibit fMLP-stimulated superoxide generation or alter the induction of PMN adhesion and interleukin-1 beta (IL-1 beta) mRNA expression by LPS or GM-CSF. Antagonism of priming by DFMO correlated with a dose-dependent attenuation of fMLP-induced intracellular Ca2+ mobilization (r > or = 0.96). Since Ca2+ plays an important role in modulating the respiratory burst in primed PMNs, this could, in part, account for the selective effects of DFMO. PMID- 9368192 TI - Neuropsychological deficits in probands from multiply-affected schizophrenic families. AB - This study was designed to determine if schizophrenics from families with more than one psychotic relative show more severe neuropsychological deficits than schizophrenics with only one psychotic relative, non-familial schizophrenics, and a group of matched normal controls. Eighty-one schizophrenic-spectrum patients were divided into three groups on the basis of the presence of psychotic disorder among first- and second-degree relatives. The three groups of schizophrenics and the normal controls were compared for differences on a brief neuropsychological testing battery. The four groups showed significant multivariate differences. Patients from multiply-affected families showed significantly greater neuropsychological dysfunction on measures of abstract concept formation, visuomotor-coordination, and attention than patients from families that had only one psychotic relative. Schizophrenics from low-density families showed more severe deficits in fine motor-control than non-familial schizophrenics. These data suggest that abnormalities in those frontal systems that are likely to mediate fine motor control and abstract concept formation may be related to the degree of familial loading for psychotic disorder. PMID- 9368193 TI - Quality of life and lifestyle disruption in euthymic bipolar disorder. AB - The objective was to assess the extent and pattern of illness intrusiveness, one measure of quality of life, in subjects with bipolar disorder (BD) and to determine whether specific illness variables had influenced the degree of intrusiveness experienced. To compare findings from BD subjects relative to published findings for subjects with chronic medical conditions. The study involved the administration of a self-report assessment tool to euthymic outpatients with BD attending a university based hospital clinic. Of the 155 eligible participants, 112 completed a standardized psychiatric interview (SADS L) and 87 of these met study criteria for euthymia and were approached to participate in the study. Sixty-eight completed self-report measures were returned. The main outcome measure was the Illness Intrusiveness Rating Scale (IIRS) which was analysed along with a composite measure of life events. It resulted that individuals' with BD experience significant illness intrusiveness into a number of life domains even after controlling for negative life events. Factors such as type of BD, the presence of a depressive episode in the preceding year and current Hamilton depression rating scale score contributed to the total illness intrusiveness. The degree of total illness intrusiveness experienced by individuals with BD was similar to that of subjects with multiple sclerosis and greater than subjects with end stage renal disease and rheumatoid arthritis. It seems apparent that quality of life, as determined by illness intrusiveness, is compromised in subjects with BD even during periods of euthymia. BD is at least as intrusive as several chronic medical conditions. Those with a type II BD report greater impairment in all domains compared with type I. Future research should determine specific psychosocial interventions aimed at reducing the impact of BD. PMID- 9368194 TI - Rates for tic disorders and obsessive compulsive symptomatology in families of children and adolescents with Gilles de la Tourette syndrome. AB - The aim of this study was to assess rates for tic disorders and obsessive compulsive psychopathology in families of children and adolescents with Gilles de la Tourette syndrome (TS). Diagnoses were based on the DSM III-R criteria. Obsessive compulsive psychopathology, that did not fulfill the criteria for obsessive compulsive disorder (OCD) was additionally assessed and termed obsessive compulsive symptoms (OCS). The authors hypothesized that comorbid OCD or OCS in TS patients predicts a higher familial loading with obsessive compulsive symptomatology. The study cohort included 87 patients with TS who were evaluated clinically and with the use of a structured psychiatric interview. All available parents (152/174; 87%), several sibs (49/93; 53%) and some second degree relatives (27/659; 4.1%) were also interviewed. For other first and second degree relatives the family history method was used. Familial rates for TS were clearly elevated. Rates for chronic tic disorders (CT) were considerably lower than in previous studies. Additionally, tic disorders not otherwise specified (TDNOS) were diagnosed in a substantial number of first degree (15/267; 5.6%) and second degree relatives (36/659; 5.5%). OCD in parents (4/174; 2.3%) did not occur in an above baseline rate. However, both OCD (14/87; 16.1%) and OCS (15/87; 17.2%) were frequently associated with TS in index patients. Interestingly, 10 of 16 fathers with OCS also had a tic disorder. Obsessive compulsive psychopathology clustered in families. It is concluded that genetic studies in TS could profit from adhering to a conservative diagnostic approach to both tic disorders and OCD. The familial clustering of OCS/OCD in conjunction with the elevated paternal rate for the co-occurrence of tic disorders and OCS might indicate heterogeneity of TS. PMID- 9368195 TI - Brain glucose metabolism in borderline personality disorder. AB - We searched for regional cerebral metabolic disturbances in patients with borderline personality disorder (BPD). Ten inpatients with BPD, no current DSM IIIR Axis I diagnosis and free of any psychotropic substances, were compared with 15 age-matched control subjects using positron emission tomography with 2-deoxy-2 [18F]fluoro-D-glucose and semiquantitative analysis of regional glucose metabolic activity. We found relative hypometabolism in patients with borderline personality disorder at the level of the premotor and prefrontal cortical areas, the anterior part of the cingulate cortex and the thalamic, caudate and lenticular nuclei. This study shows significant cerebral metabolic disturbances in patients with borderline personality disorder. These metabolic disturbances, which are similar to some of those described in other psychiatric entities, may help to understand the characteristic clinical aspects of this disorder. PMID- 9368196 TI - Effect of sleep deprivation on neuroendocrine response to a serotonergic probe in healthy male subjects. AB - Neuroendocrine responses to stimulation with a selective serotonin reuptake inhibitor (citalopram) were measured to investigate the effects of all-night sleep deprivation on serotonergic function in healthy male subjects (n = 7). We studied citalopram-stimulated prolactin and cortisol plasma concentrations in a placebo-controlled cross-over protocol following sleep and sleep deprivation. Citalopram infusion (20 mg i.v. at 14:20-14:50 h) after a night of undisturbed sleep prompted robust increases in both plasma prolactin and cortisol concentrations. Following a night of sleep deprivation, by contrast, the citalopram-induced prolactin response was blunted, but the cortisol response was not significantly altered. This differential response pattern relates to the distinct pathways through which serotonin may activate the corticotrophic and the lactotrophic systems. While an unchanged cortisol response does not indicate (but also does not refute the possibility of) an altered serotonergic responsivity following sleep deprivation, the suppressed prolactin response could reflect a downregulation of 5-HT1A or 2 receptors. An alternative, not mutually exclusive, explanation points to the possibility that sleep deprivation activates the tubuloinfundibular dopaminergic system, the final inhibitory pathway of prolactin regulation. PMID- 9368197 TI - Baseline thyroid hormones in depressed and non-depressed pre- and early-pubertal boys and girls. AB - OBJECTIVE: To examine baseline thyroid hormones in a large group of well characterized pre- and early-pubertal boys and girls who met criteria for major depressive disorder (MDD) and a comparison group of normal children without psychiatric disorders. METHODS: 45 children with MDD (10.6 years +/- 1.4 year) and 56 healthy controls (10.0 +/- 1.7 year) who participated in a large, psychobiologic protocol are included in this report. As part of the screening for eligibility, baseline samples were drawn for thyroxine (T4), triiodothyronine (T3) uptake, and thyroid stimulating hormone (TSH). Free thyroxine index (FTI) also was computed. RESULTS: Between-group analyses were carried out controlling for various demographic variables significantly related to thyroid hormones [e.g. age, gender, body mass index (BMI) and their interactions]. For many hormones there were significant effects for age and gender. For T4, MDD boys had lower T4 compared with boys in the normal group. No differences were noted between MDD girls and normal girls. For TSH, MDD boys had lower concentrations compared with normal boys while no differences were noted in girls. For T3 uptake, the MDD group had lower uptake compared with the normal group. For FTI, there were no group differences. Similar to most studies of adults with depression, all our subjects were euthyroid. Unlike the adult studies, we found lower T4 concentrations in the MDD group rather than higher. Group differences in thyroid hormones were noted primarily in boys. The large sample size of this study allowed for the control of multiple variables, which has not been done in past studies. Without such controls, true findings may be masked in other studies of depression. Thus, our findings suggest the possibility of developmental differences in the relation of thyroid hormone and depression. PMID- 9368198 TI - The use of visual analog scales in mood disorders: a critical review. AB - Patient-rated visual analog scales are a useful tool in the measurement of mood. The historical development of such scales and their design are reviewed. The simplicity of these scales promotes high compliance and, in addition, they have been shown to be both reliable and valid. While clinician-rated measurements of mood are an accepted standard, self-report of symptoms provides complementary and important information about the course and variability of illness from the patient's perspective. PMID- 9368199 TI - Computerised diagnosis in acute psychiatry: validity of CIDI-Auto against routine clinical diagnosis. AB - The validity of the self-administered CIDI-Auto for detecting ICD-10 diagnoses was assessed in a study of 126 patients admitted to an acute psychiatry unit. A comparison was made between the level of agreement of the CIDI-Auto with a psychiatrist and that between two psychiatrists. The CIDI-Auto generated an average of 2.3 diagnoses per subject, and the psychiatrists 1.3. Agreement measured by overall agreement and by Kappas between the CIDI-Auto and the psychiatrist's principal diagnosis was poor, whereas agreement between psychiatrists was good. At the level of general diagnostic class (e.g. substance use disorder, schizophrenic disorder, mood disorder), agreement between CIDI-Auto and psychiatrist on principal diagnosis was poor, Kappa = 0.23, while agreement between psychiatrists was good, Kappa = 0.69. The findings indicate that the self administered CIDI-Auto has poor validity measured against clinical diagnosis for hospitalised patients of acute psychiatric services. Poor validity of computer based diagnosis limits the diagnostic utility of these methods in clinical situations. It also creates uncertainty of diagnostic findings in survey use. PMID- 9368201 TI - Evaluation of bridging institution and housing--a joint consumer-care provider initiative. AB - 1. The most common alternative housing choice in the community for individuals with serious mental illness was a boarding home. 2. Community consumers noted that being with other people was the most important benefit of the teaching apartment, followed by eating, learning new skills, and entertainment. 3. Although they reported negative aspects about the homes, most consumers did not want to change anything about their boarding home. PMID- 9368200 TI - Preliminary evidence of the reliability and validity of the prospective life chart methodology (LCM-p). AB - This article describes the use of the NIMH prospective life-charting methodology (NIMH LCM-p) in the context of a formal double-blind, clinical trial and provides preliminary evidence of its reliability and validity. Subjects included in this report were 30 outpatients with bipolar I and II disorder who completed the first 2 years of a long-term maintenance study: 1 year on carbamazepine or lithium and a crossover to the other in the second year. The LCM-p follows the same types of guidelines and principles utilized in the previously described retrospective life chart process, allowing for continuity of illness assessment prior and subsequent to study entry. In the LCM-p, daily ratings of severity of mood symptoms based on the degree of associated functional incapacity, provide a more detailed topography of manic and depressive fluctuations. Inter-rater reliability was examined by comparing the severity of daily LCM-p ratings assigned by two raters. In order to assess the validity, we correlated the LCM-p ratings with well standardized scales, including Hamilton and Beck Depression Ratings, Young Mania Ratings and the Global Assessment Scale (GAS). The Kappa scores for inter-rater reliability demonstrated significant and satisfactory strength of agreement with no fall off over 14 days prior to the rating interview. Strong correlations were found: (1) between the LCM-p average severity for depression rating and the mean Hamilton Depression Rating (r = 0.86, p < .001), and the Beck Depression Inventory (r = 0.73, p < .001); 2) between the LCM-p average severity for mania rating and the Young Mania Rating Scale (r = 0.61, p < .001); and (3) between the LCM-p average severity and the GAS (r = -0.81, p < .001). These preliminary data suggest the reliability and validity of the NIMH-LCM-p in assessing manic and depressive episode severity. It also provides a useful continuous daily measure of affective illness-related symptom fluctuations that allows for detailed prospective assessment of frequency and pattern of illness, treatment response, and continuity with retrospective life chart assessments. PMID- 9368202 TI - "Mad" or "bad"? Evaluating the decision to hospitalize SED youth using qualitative data. AB - This study examines variables associated with positive and negative hospitalization outcomes of seriously emotionally disturbed (SED) youth, and proposes that the context of the decision-making process that takes place before hospitalization plays a role in determining outcomes. Qualitative data from 13 case histories were analyzed to determine the effects of hospitalization after a 2-year follow-up period. Several indicators that have predicted negative outcomes in earlier studies are supported here, including bizarre symptom patterns, educational impairment, and additional hospitalization during the follow-up period. There was agreement in fewer than half of the cases among research clinicians, the subject, or the subject's family regarding the outcome. Findings demonstrate the advantages of qualitative methods in determining the manner in which definitions of mental health influence hospitalization outcomes, suggesting that mental health categories are not a priori categories in the subjects' or families' minds. The social context of the decision to hospitalize is found to be a contributing factor in hospitalization outcomes. PMID- 9368203 TI - Integrated primary health care. Opportunities for psychiatric-mental health nurses in a reforming health care system. AB - As changes in our health care system evolve, making the transition to greater parity of mental and physical health is paramount to move health care in the direction of prevention and health promotion. Although parity is the goal, the most feasible path to reaching it may lie in relinking mental health to physical health in managed care models of primary health care. This article identifies emerging directions in the mental health field and points to new opportunities for advancing the practice of psychiatric-mental health nurses. PMID- 9368204 TI - Homeless lesbians: psychology of the hidden, the disenfranchised, and the forgotten. AB - 1. Lesbians in general, and homeless lesbians in particular, are neglected and ignored not only in our culture but in the nursing profession as well. 2. Nurses who work with homeless women must be aware of and sensitive to lesbian issues when interacting with any clients. 3. The problems of individual lesbians cna be as diverse as they are for any client. PMID- 9368205 TI - Health education in mental health services. AB - In the past few years, we have witnessed numerous efforts to develop health education in psychiatry. Many of them, however, were not successfully implemented. In the Netherlands, a health education method was developed in conjunction with seven mental health providers. The method promotes a more successful implementation. PMID- 9368206 TI - Coping with the dis-ease of having a disease: a holistic perspective. PMID- 9368207 TI - Maternal ego development and mother-infant interaction in drug-abusing women. AB - The purpose of this study was to expand our knowledge about factors in substance abusing women, other than chronic drug abuse, that may influence maternal caregiving behaviors. Specifically, the study explored relationships between maternal characteristics and mother-infant interaction in a sample of drug abusing women to determine whether drug-addicted mothers' level of ego development affected mother-infant interaction at 1 month. Data collection occurred during a prenatal lab visit and 1 month postpartum and included a clinical interview, self-report on participants' addiction severity, clinical personality inventory, ego development test, and videotaped observation of mother infant feeding interactions. Only ego development, and to a lesser degree psychological symptoms associated with substance abuse, were found to be significant predictors of maternal-child interaction at 1 month. This points to the need to focus on building internal resources in providing substance abuse treatment and other services for substance-abusing mothers. PMID- 9368208 TI - Psychodynamic psychotherapy of the intravenous cocaine abuser. AB - Using the psychodynamic psychotherapeutic treatment of a 23 year old female cocaine-addicted client as an example, the author describes the theoretical concepts and clinical methods he has found useful in this context. Using an approach that draws on the work of Winnicott (1971, 1986, 1992) and Malan (1979), the author describes how psychodynamic psychotherapy can be effective in facilitating change in an addiction in an outpatient setting. Winnicott's work provides the context for the treatment while Malan's model provides a structure for the therapeutic process. Within the context of a holding environment, links between past trauma and current drug use as a defence are explored. Also discussed are the use of dream material, the facilitation of the corrective emotional experience, and the complementary use of 12-step programs in the therapeutic process. PMID- 9368209 TI - An open trial of transdermal nicotine replacement therapy for smoking cessation among alcohol- and drug-dependent inpatients. AB - An open trial of transdermal nicotine replacement for smoking cessation was conducted. Over a 7-month period, all patients admitted to the inpatient alcohol and drug treatment unit of the Seattle Veterans Affairs Medical Center, (n = 207) were offered the opportunity to participate in an open trial of transdermal nicotine replacement for smoking cessation. Forty-nine (23.7%) elected to attempt cessation with transdermal nicotine during their inpatient treatment episodes. These subjects received no psychosocial treatments directed specifically at smoking cessation. They smoked a mean of 28.5 (SD = 16.4) cigarettes per day and obtained a mean score of 8.3 (SD = 1.9) on the Fagerstrom Test for Nicotine Dependence. Subjects remained on transdermal nicotine an average of 18.8 (SD = 8.2) days with desire to resume smoking the major reason for discontinuation. Seven subjects (14.3%) self-reported tobacco abstinence at 21 days, and 5 (10.2%) self-reported abstinence as outpatients at 6 weeks. These results show that a substantial proportion of alcohol- and drug-dependent patients entering inpatient treatment are willing to attempt alcohol and illicit drug cessation and tobacco cessation simultaneously and that transdermal nicotine holds promise as a treatment modality in this population. PMID- 9368210 TI - Treatment of substance-abusing jail inmates. Examination of gender differences. AB - Females incarcerated for drug-related offenses represent one of the fastest growing populations within jails and prisons. The few studies of female offenders with substance abuse disorders depict a population with multiple psychosocial problems and treatment needs, and one that is characterized by frequent exposure to sexual abuse and other violence. The current study examined intake assessment results from a sample of 1,655 substance-involved jail inmates referred to a jail treatment program in Tampa, Florida, including 26% female and 74% male inmates. The study was designed to identify gender differences in psychosocial characteristics and substance abuse treatment needs among jail inmates. Results indicate that female inmates more frequently experienced employment problems, had lower incomes, more frequently reported cocaine as the primary drug of choice, and were more likely to report depression, anxiety, suicidal behavior, and a history of physical and sexual abuse. Implications for developing specialized treatment approaches for female offenders are discussed, including use of integrated treatment strategies. PMID- 9368211 TI - Sexual and physical abuse: do they compromise drug treatment outcomes? AB - Histories of sexual and physical abuse are frequently reported by individuals participating in substance abuse treatment, these experiences may be associated with psychopathology and poor drug treatment outcomes. This paper presents the findings from a longitudinal study of 330 subjects participating in 26 outpatient treatment programs. Sexual abuse among women was associated with higher levels of depression, anxiety, suicidal ideation, suicide attempts, and PTSD, while physical abuse was associated with fewer psychological disturbances. For men, sexual abuse was associated only with anxiety. Physical abuse was associated with depression, anxiety, suicidal ideation, and PTSD. However, no significant association was found between sexual and physical abuse, and lower levels of treatment participation or drug use at follow-up. These findings indicate that there is a complex connection between abuse, psychopathology, treatment participation, and relapse. Clinical and research implications of these findings are discussed. PMID- 9368212 TI - Predictors of prenatal substance use and birth weight during outpatient treatment. AB - This paper presents evaluation results of a CSAP-funded case management project associated with an outpatient substance abuse treatment (SAT) program for women and their children. Key findings are: (a) case management and threat of child protective services encourage retention in SAT during pregnancy, (b) retention in SAT has a positive effect on reducing illicit substance use, (c) receiving methadone during pregnancy has a negative effect on reducing illicit substance use, and (d) reduction in illicit substance use has a positive effect on birth weight. These findings indicate retention in SAT and decreased illicit drug use are associated with improved infant birth weight, which is associated with other improvements, such as decreased infant mortality and morbidity. The finding of a relationship between methadone maintenance treatment (MMT) and illicit drug use creates a dilemma for practice: to what extent should the dose of methadone be decreased during pregnancy, given the fact that women may then increase illicit use of drugs. PMID- 9368213 TI - Characteristics of cocaine-addicted individuals who abuse their partners. AB - The purpose of this study was to determine what proportion of individuals entering treatment for cocaine dependence admitted to battering an intimate partner and to compare the characteristics of those who were not identified as batterers. Of the 77 men in the sample, 38% were characterized as cocaine dependent batterers. The batterers and nonbatterers were found to differ on a variety of background and assessment variables. Cocaine-dependent batterers more often reported a history of serious conflict with their sexual partner, trouble controlling violent behavior, greater psychiatric disturbance, difficulty relaxing, and being easily annoyed. A summary of the findings as well as implications for future research are discussed. PMID- 9368214 TI - Bulimia and dextromethorphan abuse. A case study. AB - The comorbidity of bulimia and substance abuse is significant. The substance that is abused may vary and the abuse potential for nonillicit substances may be overlooked. This paper presents the first case reported of dextromethorphan abuse and bulimia. It demonstrates the complexity of assessment and treatment of bulimia and substance abuse of over-the-counter medications. PMID- 9368215 TI - The use of a mental status examination in a chemical dependence treatment program. AB - Current chemical dependence treatment programs place significant cognitive demands on patients early in abstinence. Unfortunately, many chemically dependent persons have significant cognitive deficits in the acute and post-acute stages of withdrawal. Constraints on resources often make thorough evaluation of cognitive status impractical. We examined the utility of a brief structured mental status examination, the Cognitive Capacity Screening Examination (CCSE), to identify cognitive deficits within the first week of admission to an inpatient chemical dependence treatment program. Although both age and educational level influenced CCSE total score to a statistically significant degree, the magnitude of their influence was of doubtful clinical importance. Findings suggest that the CCSE total score is not sufficiently sensitive to detect the deficits seen in chemically dependent individuals. However, a more detailed item analysis can provide useful information to the clinician. Normative data and recommendations for use of the CCSE with chemically dependent populations are provided. PMID- 9368216 TI - Measuring problem drinking in first time offenders. Development and validation of the College Alcohol Problem Scale (CAPS). AB - Research on college drinking continues to justify serious concerns for the psychological, social, and physical well-being of young persons who abuse alcohol. However, despite considerable interest and research in this regard, there are few valid, reliable and clinically useful brief screening instruments available to measure youthful drinking problems. The current study of 315 college students cited their first time for breaking university drinking rules describes the development and validation of the College Alcohol Problem Scale (CAPS) for measuring different psychosocial dimensions of problem drinking in college students. Two related but distinct factors emerged defining Socio-Emotional and Community Problems. These two factors explained almost two thirds of the variance, and showed very good internal reliabilities. MANOVA analysis demonstrated concurrent validity for the CAPS with both a measure of heavy drinking derived from the QFI and a modified version of the MAST. Implications for using the CAPS for identifying potential drinking problems in young persons are emphasized. PMID- 9368217 TI - Predicting length of stay of substance-using pregnant and postpartum women in day treatment. AB - Pregnant and postpartum substance-using women are a special population whose needs do not reflect those of the general substance-using communities. This study examined length of stay in a federally funded day treatment demonstration program in order to identify predictor variables that may help identify pregnant and postpartum substance-using women at high risk for dropping out of treatment. Variables from intake and exit questionnaires on a sample of 163 women were analyzed using multiple regression on both days in treatment and the logarithmic transformation of days in treatment. Few predictor variables were identified, although findings suggest that if a women is younger and self-referred, she may leave treatment sooner. As one of the first sets of published data on pregnant and postpartum women and retention in treatment, this study lays the groundwork for future research on the retention of pregnant and postpartum women in treatment, thereby facilitating the success of these women in overcoming their addiction. PMID- 9368218 TI - Combination of the dopaminergic agent, phentermine, and the serotonergic agent, fenfluramine, in the treatment of cocaine dependence. PMID- 9368219 TI - Transthoracic needle biopsy: an overview. AB - The parallel development of cross-sectional detection and characterization of thoracic lesions with advances in biopsy needle design and increased access to expert cytopathology has led to an expanded role for image-guided transthoracic needle biopsy (TNB) in the diagnostic evaluation of thoracic lesions. There is a growing list of indications for TNB, the most important of which is the evaluation of a solitary pulmonary nodule. A key preparatory step in planning TNB is conducting a preprocedural consultation with the pathologist, which maximizes the likelihood of a positive diagnostic outcome. Computed tomography (CT) has rapidly become the guidance modality of choice for performing TNB. While TNB is highly sensitive in the diagnosis of carcinoma, methods used to enhance the diagnostic yield for other neoplasms and benign conditions include coaxial needle placement for multiple samplings, selective use of core biopsy needles to obtain histologic specimens, and the performance of ancillary tests on the aspirated material. The complications of TNB are well recognized and include pneumothorax, hemorrhage, and systemic air embolism. Although the results of recent cost analysis studies suggest a central role for TNB in the diagnosis of the indeterminate lung lesion, the availability and yield of alternative diagnostic and therapeutic techniques including positron-emission tomography scanning and video-assisted thoracoscopic surgery will determine its true utility. PMID- 9368220 TI - Transthoracic hilar and mediastinal biopsy. AB - Transthoracic needle biopsy (TNB) of the mediastinum is an accurate, safe, and cost-effective diagnostic tool for the evaluation of mediastinal masses and lymphadenopathy. The technique is most useful in the staging of carcinoma, where it serves as a less expensive and minimally invasive alternative to mediastinoscopy for establishing unresectability. With recent advances in immunohistochemical and core-biopsy techniques, TNB has become more accurate for establishing the initial diagnosis of lymphoma and for confirming recurrent disease. Core-needle biopsy has improved the accuracy of TNB and is particularly useful when fine-needle aspiration fails to yield a specific diagnosis, or when lymphoma or a noncarcinomatous lesion is suspected. PMID- 9368221 TI - Needle-aspiration lung biopsy: a comprehensive approach to complication reduction. AB - Complications in needle-aspiration lung biopsy are often related to technique. A step-by-step discussion of lung biopsy focusing on complication reduction is presented. Preparation, needle selection, biopsy approach, needle manipulations, sampling, postprocedure care, and complication management are discussed in detail. PMID- 9368222 TI - Ultrasound-guided transthoracic biopsy of peripheral lung, pleural, and chest wall lesions. AB - Ultrasound (US)-guided transthoracic biopsy is well suited for the sampling of those mediastinal, hilar, pleural, chest-wall, and peripheral lung lesions that provide an adequate acoustic window to the transducer. Chest-wall, pleural, and peripheral lung lesions are generally hypoechoic relative to their surrounding tissues. A special puncture transducer is used to perform US-guided biopsy with real-time visualization of the biopsy needle and the lesion. For vascular lesions and lesions adjacent to mediastinal vessels, a color Doppler puncture device is now available. The accuracy of US-guided biopsy of peripheral lung lesions or chest-wall lesions is 88% to 100%, with particular utility in the diagnosis of pulmonary masses with large necrotic centers. Other lung lesions amenable to US guided biopsy diagnosis include those producing superior vena cava (SVC) syndrome, Pancoast's syndrome, or obstructive pneumonitis. Pulmonary consolidation, lung abscess, and parapneumonic effusions are easily sampled for microbiologic diagnosis. The peripheral nature of lesions accessed by US guidance accounts for a very low rate of complications. Although US-guided needle biopsy requires certain expertise, the technique is relatively easy to master and can be performed in many situations where computed tomography-guided biopsy would previously have been used. PMID- 9368223 TI - Image-guided localization for video-assisted thoracic surgery. AB - Video-assisted thoracic surgery (VATS) has become a useful diagnostic and therapeutic tool in the management of lung, pleural, and mediatstinal disease. Preoperative image-guided localization is performed to aid the surgeon in the thoracoscopic resection of small lung lesions that would otherwise be difficult to resect. This article describes the techniques of localization and reviews our experience with this procedure. While the majority of localization procedures are performed during an immediately preoperative computed tomography (CT), the use of intraoperative lesion localization using an endosonographic probe has been reported. The need for localization before resection is dependent on the skill and experience of the thoracoscopist and the characteristics of the lung lesions. PMID- 9368225 TI - The ghosts of Byzantium. PMID- 9368224 TI - Rontgen's ghosts: photography, X-rays, and the Victorian imagination. PMID- 9368226 TI - Gertrude Stein and the politics of literary-medical experimentation. PMID- 9368227 TI - War, Walt Whitman, and William Osler. PMID- 9368228 TI - Melville's Pierre and nervous exhaustion; or "the vacant whirlingness of the bewilderingness". PMID- 9368229 TI - Neurology and the novel: Alexander Monro primus and secundus, Robinson Crusoe, and the problem of sensibility. PMID- 9368230 TI - Voltage dependence of the pharmacological Mg2+ block of the Ca2+ entry into vascular smooth muscle cells. AB - We studied the voltage dependence of the inhibitory effects of the Ca2+ antagonist Mg2+, compared to nifedipine, on the transsarcolemmal Ca2+ uptake into primary monolayers of smooth muscle cells obtained from pig coronary arteries. The cellular Ca incorporation was analyzed by liquid scintillation. Depolarization was produced by elevation of K+0. The data suggest that depolarization known to improve the inhibition by organic Ca2+ antagonists of L type voltage-gated Ca2+ channels attenuates the Ca2+ antagonism of Mg2+ at vascular smooth muscle cells. PMID- 9368231 TI - Magnesium deficiency increases vasoconstrictor activity without affecting blood pressure of aged spontaneously hypertensive rats. AB - This study examines the effect of long-term magnesium-deficient diet on blood pressure and vascular reactivity in aged spontaneously hypertensive rats (SHR) with established hypertension. Thirty-one-week old male SHR received control (0.15 per cent magnesium) and magnesium-deficient (0.015 per cent magnesium) diets for 30 weeks. Systolic blood pressure was measured by tail-cuff method. At the end of the study, the heart, aorta and kidney were collected to measure total magnesium and calcium concentrations; the ex vivo effects of the different magnesium diets on vascular reactivity were examined in isolated aorta and in the isolated perfused mesenteric vascular bed. After 30 weeks, magnesium deficiency had no effect on systolic blood pressure and heart rate of SHR. The tissue concentrations of total magnesium in aorta, heart and kidney were not modified by magnesium deficient diet. Total calcium concentration was significantly higher in the heart of the SHR fed the magnesium-deficient diet (p < 0.01). The aortic responsiveness to contractile agents norepinephrine, endothelin-1, CaCl2 and KCl, and to vasorelaxant agents acetylcholine and isoproterenol were not modified by magnesium deficiency. The vasoconstrictor activity to norepinephrine, CaCl2 and KCl was significantly enhanced in the isolated perfused mesenteric vascular bed of magnesium-deficient SHR (p < 0.05). In conclusion, magnesium deficient diet fails to elevate blood pressure in aged SHR maintained on deficiency for 30 weeks despite an enhanced ex vivo vasoconstrictor activity. PMID- 9368232 TI - Reduction of the frequency of occurrence of low magnesium induced field potentials in the hippocampus slice preparation of guinea pigs: a good screening tool for calcium antagonistic effects of anticonvulsant and antipsychotic drugs. AB - An ideal model for in vitro research purposes of epilepsies should reflect the different clinical aspects of epileptic seizures, both in vivo and, as far as comparisons are possible, in vitro. It should induce long-term changes on a cellular level analogous to what is observed in epileptic patients, and should be triggered by varying endogenous physiological processes without additional exogenous drugs. These criteria are satisfied in the low magnesium model of epilepsy. Reducing Mg2+ below physiological concentrations or omitting it from artificial cerebrospinal fluid in vitro induces synchronized depolarization shifts in limbic-cortical networks which can be easily recorded extracellularly with a basic electrophysiological set up. These depolarization shifts resemble an increase of the calcium flux into the cell. Multiple depolarizing mechanisms such as NMDA receptor activation or prevention of presynaptic adenosine action converge onto this central pathway. It is hypothized that disturbed calcium homeosthasis is not only a characteristic of epilepsies, but also of affective disorders. Thus, the low magnesium model enables us to screen substances in vitro not only for antiepileptic, but also potential psychiatric use by testing them for calcium antagonistic properties. PMID- 9368233 TI - Compared effects of high oral Mg supplements and of EDTA chelating agent on chronic lead intoxication in rabbits. AB - Our previous experiments showed that excessive oral Mg intake has beneficial effects in chronic Pb poisoning, inducing decrease of Pb body burden and its increased elimination via urine. The aim of this work was to investigate and to compare the effect of Mg on urinary Pb elimination with the effect of calcium disodium edetate (CaNa2EDTA)--chelating agent currently used in therapy of chronic Pb intoxication. Besides, under the same experimental conditions, biochemical parameters protoporphyrin IX (ppIX), zinc protoporphyrin (Znpp) and delta-aminolevulinic acid (ALA) were determined. Experiments were carried out on rabbits previously intoxicated for 4 weeks with 20 mg Pb/kg b.w. per day. After the period of intoxication, one group of animals was given per os, for 28 days, 40 mg Mg/kg, the other one was i.v. treated for 7 days with 15 mg CaNa2EDTA/kg (therapeutic doses), while the third one (rabbits without therapy) served as a control. During the period of detoxication, lead was determined in blood and urine samples, and ppIX and Znpp were determined in blood and ALA in urine. Results suggest that oral treatment with magnesium, although inducing later Pb elimination than EDTA, has even better effect on investigated biochemical parameters than chelating therapy. PMID- 9368234 TI - Effect of intensive i.v. + oral magnesium supplementation on circulating ion levels, lipid parameters and metabolic control in Mg-depleted insulin-dependent diabetic patients (IDDM). AB - Magnesium depletion in diabetic patients is a frequent observation and is involved in the pathogenesis of acute and chronic complications. In this study the effect of a 10 week intensive oral + i.v. supplementation of Mg was studied in 11 depleted IDDM patients with stable metabolic control. Ionized Mg decreased and erythrocyte Mg increased significantly together with an increased storage of Mg in the body demonstrated with a classical retention test. Normalization of the Mg parameters was however not obtained. Lipid parameters and metabolic control remained unchanged. PMID- 9368235 TI - Assessment of magnesium levels in children with attention deficit hyperactivity disorder (ADHD). AB - A positive influence of magnesium in the prevention and treatment of hyperactivity in children is more and more frequently raised in the literature. The aim of our work was to estimate magnesium contents in children with attention deficit hyperactivity disorder, (ADHD). The investigations comprised 116 children (94 boys and 20 girls), aged 9-12 years, with recognized ADHD. In 68 out of 116 patients examined ADHD occurred with other coexisting disorders specific to the developmental age and in the remaining 48 patients it occurred together with disruptive behaviour. Magnesium levels have been determined in blood serum, red blood cells and in hair with the aid of atomic absorption spectroscopy. Magnesium deficiency was found in 95 per cent of those examined, most frequently in hair (77.6 per cent), in red blood cells (58.6 per cent) and in blood serum (33.6 per cent) of children with ADHD. The conclusion from the investigations is that magnesium deficiency in children with ADHD occurs more frequently than in healthy children. Analysis of the material indicated the correlation between levels of magnesium and the quotient of development to freedom from distractibility. PMID- 9368236 TI - The effects of magnesium physiological supplementation on hyperactivity in children with attention deficit hyperactivity disorder (ADHD). Positive response to magnesium oral loading test. AB - Children with ADHD are 'a group at risk' as far as their further emotional and social development and educational possibilities are concerned, and the consequences of the lack of an appropriate therapy appears to be serious. Some of these children do not respond to prevailing therapy methods. It is reported that dietetic factors can play a significant role in the etiology of ADHD syndrome, and magnesium deficiency can help in revealing hyperactivity in children. The aim of our work was to assess the influence of magnesium supplementation on hyperactivity in patients with ADHD. The examination comprised 50 hyperactive children, aged 7-12 years, who fulfilled DSM IV criteria for ADHD syndrome, with recognized deficiency of magnesium in the blood (blood serum and red blood cells) and in hair using atomic absorption spectroscopy. In the period of 6 months those examined regularly took magnesium preparations in a dose of about 200 mg/day. 30 of those examined with ADHD showed coexisting disorders specific to developmental age, and 20 of them showed disruptive behaviour. The control group consisted of 25 children with ADHD and magnesium deficiency, who were treated in a standard way, without magnesium preparations. 15 members of this group showed coexisting disorders specific for developmental age, and 10 members showed disruptive behaviour. Hyperactivity was assessed with the aid of psychometric scales: the Conners Rating Scale for Parents and Teachers, Wender's Scale of Behavior and the Quotient of Development to Freedom from Distractibility. In the group of children given 6 months of magnesium supplementation, independently of other mental disorders coexisting with hyperactivity, an increase in magnesium contents in hair and a significant decrease of hyperactivity of those examined has been achieved, compared to their clinical state before supplementation and compared to the control group which had not been treated with magnesium. PMID- 9368237 TI - Mechanisms of in vitro cardioprotective action of magnesium on the aging myocardium. AB - Studies examining the effects of aging on the myocardium have indicated that with advancing age there are anatomical, mechanical, ultrastructural, and biochemical alterations which compromise the adaptive response of the heart and make the senescent myocardium less tolerant to surgically-induced ischemia. With the increased incidence of elderly patients as candidates for complex cardiac surgery, the investigation into methods which will increase survivability and enhance myocardial protection are of paramount importance. Previous reports have indicated that surgically-induced global ischemia is associated with alteration in cytosolic calcium accumulation ([Ca2+]i), and that the level of post-ischemic functional recovery can be correlated with control of [Ca2+]i Cardioplegia (high potassium arrest) partially ameliorates the adverse effects associated with global ischemia however; the use of magnesium (magnesium supplemented potassium icardioplegia) has been shown to provide superior myocardial protection during global ischemia and to allow for enhanced post-ischemic functional recovery. The cardioprotective mechanisms of magnesium supplemented potassium cardioplegia which allow for decreased morbidity and mortality in the cardiac surgical patient has been shown to act at the level of the sarcolemma, mitochondria and the nucleus. and may be associated with myocardial gene expression in the aged heart. In this report these mechanisms are reviewed. PMID- 9368238 TI - Neurotic, neuromuscular and autonomic nervous form of magnesium imbalance. AB - The nervous form of magnesium imbalance represents the best documented experimental and clinical aspects of magnesium disorders. The nervous form of primary magnesium deficit (MD) in the adult appears as the best descriptive model for analysis of the symptomatology, aetiology, physiopathology, diagnosis and therapy of the most frequent form of MD. Nervous hyperexcitability due to chronic MD in the adult results in a non-specific clinical pattern with associated central and peripheral neuromuscular symptoms, analogous to the symptomatology previously described in medical literature as latent tetany, hyperventilation syndrome, spasmophilia, chronic fatigue syndrome, neurocirculatory asthenia and idiopathic Barlow's disease. On encountering this non-specific pattern, the signs of neuromuscular hyperexcitability are of much greater importance. Trousseau's sign is less sensitive than Chvostek's sign, but their sensitivities are increased by hyperventilation (Von Bondsdorff's test). Examination of the precordial area will be conducted in order to search clinical stigmata of mitral valve prolapse (MVP) which is a frequent dyskinesia due to chronic MD (about a quarter to one-third of cases). The electromyogram (EMG) shows one (or several) trains of autorhythmic activities beating for more than 2 min of one of the three tetanic activities (uniplets, multiplets or 'complex tonicoclonic tracings') during one of the three facilitation procedures: tourniquet-induced ischaemia lasting 10 min. post-ischaemia lasting 10 min after the removal of the tourniquet and hyperventilation over 5 min. A repetitive EMG constitutes the principal mark of nervous hyperexcitability (NHE) due to MD. The echocardiogram (ECC) is the best tool for detecting MVP, the 2-dimensional ECC with pulsed Doppler being more accurate than time-motion ECC. The routine ionic investigations comprise five static tests: plasma and erythrocyte magnesium, plasma calcium and daily magnesiuria and calciuria. An evaluation of magnesium intake is desirable. Normal concentrations of magnesium in blood do not rule out the diagnosis of the nervous form of primary chronic MD. The histograms of MD group reveal Gaussian type magnesaemias with significantly lower means and the constituent elements can be individually hypo- (one-third of cases), normo- (about two-thirds of cases) and even, exceptionally, hyper-magnesaemic. The diagnosis of MD requires an oral magnesium load test. At physiological dose (5 mg of Mg/kg/day), oral magnesium is totally devoid of the pharmacological effects of parenteral magnesium. Corrections of symptomatology by this oral physiological magnesium load is the best proof that it was due to magnesium deficiency. In particular clinical forms, more sophisticated studies may be useful: standard and quantitative electroencephalograms, electropolygraphic studies of afternoon sleep, electronystagmography, optokinetic test, skin conductance reflex, psychometric inventories, standard or monitoring electrocardiogram, treadmill test, other static and dynamic investigations: e.g. ionized free Mg2+, lymphocyte Mg, brain Mg, cerebrospinal Mg, Mg balance, Mg parenteral load test, glucose load, and even radio-isotope study, the only one able to reveal intestinal magnesium hypersecretion. Nervous primary chronic MD progresses by phases of decompensation against a background of latency. Marginal magnesium deficiency, that is to say an insufficient magnesium intake which merely requires simple oral physiological supplementation, is fundamental in the aetiology of primary magnesium deficit. However a constitutional homeostatic lability of the nervous system or of magnesium metabolism such as belonging to the B35 type of HLA group must be involved. Part of the aetiology of this magnesium deficit is a magnesium depletion, where the disorder which induces magnesium deficit is related to a dysregulation of the control mechanisms of magnesium status which requires a more or less difficult PMID- 9368239 TI - Effect of fever on capillary refill time. AB - OBJECTIVE: To assess the effect of fever on capillary refill time in children. DESIGN: Prospective cohort study. SETTING: Tertiary care children's hospital emergency department (ED). PARTICIPANTS: Convenience sample of 234 children age one month to five years presenting to the ED with a complaint of vomiting, diarrhea, or poor oral fluid intake. INTERVENTION: None. MEASUREMENTS: Before any therapy, capillary refill was measured according to a standard protocol. Rectal temperature was measured in children less than three years old, oral temperature in older children. Fluid deficit was calculated as the percentage difference between initial weight and stable weight following treatment. MAIN RESULTS: Among the 80 children with dehydration, defined as a deficit of > or = 5% of body weight, mean capillary refill was 2.0 +/- 1.0 seconds, versus 1.3 +/- 0.5 seconds in the well hydrated group (P < 0.001). Within each group, mean capillary refill time for febrile patients (temperature > or = 38.3 degrees C) was essentially the same as in those without fever. Using a two-second upper limit of normal, prolonged capillary refill had a sensitivity of 0.44 and specificity of 0.94 for diagnosing dehydration; the diagnostic performance did not differ when stratified by presence or absence of fever. CONCLUSIONS: Presence of fever does not have a clinically important effect on capillary refill time in children. PMID- 9368240 TI - Pediatric emergency physicians and communicable diseases: can we be trusted to take care of ourselves? AB - OBJECTIVE: To determine if pediatric emergency physicians (PEP) are following Centers for Disease Control and Prevention (CDC) recommendations that all health care workers receive routine vaccines and annual tuberculosis screens. DESIGN: A two-page mail survey with one follow-up mailing. PARTICIPANTS: All active members of the American Academy of Pediatrics (AAP), Section on Emergency Medicine. Additional inclusion criteria were completion of training and employment in an emergency setting. RESULTS: Of 407 surveys, 286 (60%) were returned; 209 met inclusion criteria. Proof of immunization was not required of 43% of PEP; 42% were not required to have an annual tuberculosis (TB) screen. PEP reported immunity to the following: polio (95%), measles (94%), hepatitis B (91%), rubella (90%), mumps (90%), varicella (90%), and diphtheria-tetanus (86%). However, only 72% received a TB screen, and 60% received an influenza vaccine within the past year. Proof of vaccination for employment was required by 57/85 hospitals, 47/79 universities, and 6/32 self-employed/group practices (chi 2, P < 0.001). Proof of an annual TB screen was required by 64/87 hospitals, 44/82 universities, and 8/32 self-employed/group practices (chi 2, P < 0.001). PEP were more likely to have had a recent annual TB screen if required by their employer (104/117) than if left to their own initiative (42/87) (chi 2, P < 0.001). CONCLUSIONS: Although PEP are well protected against most vaccine-preventable diseases, many are not receiving annual TB screens nor influenza vaccines. The CDC guidelines are not being routinely followed by PEP. PMID- 9368242 TI - Duration of fever and its relationship to bacteremia in febrile outpatients three to 36 months old. The Occult Bacteremia Study Group. AB - OBJECTIVE: To determine the relationship between the duration of fever as reported by caregivers and the likelihood of occult bacteremia in highly febrile young children. METHODS: This is a prospective cohort study performed as part of a prior, multicenter, randomized, interventional trial of oral versus intramuscular antibiotics in the prevention of complications of occult bacteremia in febrile children presenting to nine urban pediatric emergency departments at eight medical centers. Participants included children three to 36 months of age with a temperature of > or = 39.0 degrees C and a nonfocal illness (or uncomplicated otitis media) managed as outpatients. The outcome measure was the presence of bacteremia. RESULTS: Of the 6680 randomized patients, 6619 (99.1%) had a culture of their blood and a valid reported duration of fever. The median duration of fever in patients with bacteremia (n = 192) and without bacteremia (n = 6427) was the same, one to two days, but the mean rank of patients with bacteremia was significantly lower than that of patients without bacteremia (P + 0.0009). A significantly greater proportion of patients with fever < 1 day had bacteremia than patients with fever > or = 1 day (P = 0.004), and a significantly greater proportion of patients with fever < 2 days had bacteremia than patients with fever > or = 2 days (P = 0.009). The sensitivity, specificity, positive predictive value, and negative predictive value of fever < 1 day in detecting occult bacteremia were 40.1, 69.8, 3.8, and 97.5%, respectively. PMID- 9368241 TI - Comparison of self-inflating bags with anesthesia bags for bag-mask ventilation in the pediatric emergency department. AB - OBJECTIVE: To compare bag-mask ventilation performed by emergency department (ED) personnel using anesthesia bags (AB) and self-inflating bags (SIB). SETTING: ED in a teaching children's hospital where the AB is the device used during resuscitations. DESIGN: Experimental study. Bag-mask ventilation was evaluated with an infant resuscitation mannequin equipped to measure airway volumes and pressures. Pediatric residents, ED nurses, and pediatric emergency medicine fellows performed bag-mask ventilation with AB and SIB and rated their confidence using each device. MAIN OUTCOME MEASURE: Ventilation failure rates. RESULTS: Seventy subjects participated (17 interns, 16 junior residents, 13 senior residents, 10 fellows, and 14 nurses). There were 13 failures with the AB (18.6%) versus 1 (1.4%) with the SIB (P < 0.01) [95% confidence interval: 5-29%], with a significant difference even after excluding the least experienced subjects. There was no difference in high pressure breaths delivered (SIB 19% vs AB 15%, P = 0.4) and a higher incidence of hyperventilation with the SIB (67 vs 25%, P < 0.01). While using the SIB, 19 (27%) of the subjects did not turn on the O2 flow. There was no difference in pretest confidence rating, but the posttest confidence rating was higher for the SIB (P < 0.05). CONCLUSIONS: Compared to SIB use for bag-mask ventilation in an ED, AB use resulted in more ventilation failures, no advantage in preventing excessive airway pressures, and less confidence among operators. The SIB should be the first choice for bag-mask ventilation in the ED, with attention to maximize oxygen delivery. PMID- 9368243 TI - Factors influencing termination of resuscitative efforts in children: a comparison of pediatric emergency medicine and adult emergency medicine physicians. AB - OBJECTIVES: To examine factors that influence termination of resuscitative efforts (TORE) and compare pediatric emergency medicine (PEM) and general emergency medicine (GEM) physicians regarding TORE in children. DESIGN: Cross sectional survey. PARTICIPANTS: All physicians board-certified in PEM as of November 1993 and a random sample of board-certified GEM physicians listed in the 1993 American College of Emergency Physicians directory. INTERVENTIONS: Self administered questionnaires were mailed to participants who were asked about experience providing pediatric cardiopulmonary resuscitation (CPR) and demographic information. We posed a series of management questions eliciting factors that influence TORE decision-making in single context and case scenario format. Specific emphasis was placed on the influence of time and epinephrine dosing. RESULTS: One hundred and sixty (70%) PEM and 127 (62%) GEM responded. These groups differed significantly in years of experience (PEM 8.2, GEM 11.8), urban practice setting (PEM 84%, GEM 32%) and number of pediatric cardiopulmonary resuscitations per year (PEM 10.6, GEM 4.8), P < 0.001 for all. There were no significant differences between groups regarding features pathognomonic of death. PEM were more likely to consider low blood pH and iatrogenic causes of arrest as factors influencing TORE; GEM were more likely to consider co-morbid conditions (P < 0.05 for all). Medians for time estimates of minimum minutes of pulselessness that influence TORE were: PEM 26 to 30 minutes, GEM 31 to 35 minutes for both prehospital and emergency department settings (P < 0.05 for each). Approximately 20% of all respondents did not place a strict limit on time of pulselessness when determining TORE. No difference was observed between groups regarding maximum doses of epinephrine used prior to TORE. However, fewer GEM (50%) than PEM (75%) utilize "high dose" epinephrine according to current Pediatric Advanced Life Support (PALS) guidelines (P < 0.05). PEM physicians were more than two times more likely to terminate resuscitative efforts if return of spontaneous circulation was not achieved by 25 minutes compared to GEM physicians for both prehospital time of pulselessness [odds ratio 2.1, 95% confidence interval (1.01, 4.5)] and emergency department time of pulselessness [odds ratio 2.2, confidence interval (1.1, 4.6)]. CONCLUSIONS: 1) Several laboratory and clinical factors significantly influence physician's decisions regarding TORE; 2) regardless of setting, time of pulselessness does appear to be an influential factor in determining when to terminate resuscitation in children for most physicians; 3) PEM physicians are more likely to terminate resuscitative efforts than are GEM physicians if return of spontaneous circulation is not achieved by 25 minutes; 4) a significant number of PEM and GEM physicians do not use high dose epinephrine in accordance with current PALS recommendations. PMID- 9368244 TI - Effects of parental presence during young children's venipuncture. PMID- 9368245 TI - Tuberculous lymphadenopathy masquerading as a bronchial foreign body. AB - A case of recent onset of wheezing with clinical and radiologic findings suggestive of foreign body aspiration is presented. Rigid bronchoscopy revealed an extraluminal compression of the airway. Histopathologic and microbiologic examination revealed tuberculous lymphadenopathy. PMID- 9368246 TI - An infant with fever and drooling: infection or trauma? PMID- 9368247 TI - Blunt abdominal injury: simultaneously occurring liver and pancreatic injury in child abuse. PMID- 9368248 TI - A case of orbital pseudotumor masquerading as orbital cellulitis in a patient with proptosis and fever. PMID- 9368249 TI - "Cloniderm" toxicity: another manifestation of clonidine overdose. AB - We present a case of accidental transdermal clonidine toxicity in a six-year-old child who was applying a clonidine patch intermittently to her dermis in the mistaken assumption that it was an adhesive bandage. Although the child appeared to be drug toxic, she repeatedly denied ingestion of any substances to family, paramedics, and hospital staff but was not initially questioned regarding dermal exposure. In dealing with drug toxic states in which the differential diagnosis includes drugs available as transdermal delivery systems, the evaluation should include questions regarding possible dermal exposure and a thorough skin examination. PMID- 9368250 TI - Appendicitis: an unusual cause of pneumonia and impending shock in a toddler. AB - Owing to its lower incidence in young children, appendicitis is not as often thought of as a common cause of abdominal pain and vomiting in this age group. However, because of its higher incidence of morbidity (perforation and peritonitis), it should be considered in any young child with either significant abdominal pain or vomiting, even in the presence of another plausible etiology such as pneumonia. PMID- 9368251 TI - Accidental strangulation by a motor vehicle window. AB - OBJECTIVE: To describe a child who was asphyxiated by a motor vehicle window and to review the relevant literature. DESIGN: Case report. SETTING: A 402-bed tertiary care medical center in La Crosse, WI. PATIENT: Four-year-old girl. INTERVENTIONS: Supportive pediatric critical care. MAIN OUTCOME MEASURES: None. RESULTS: The patient did not survive. CONCLUSIONS: Parents must assume responsibility for restraining their children in motor vehicles. Parents must not leave children alone in motor vehicles. Parents must become "more injury literate." PMID- 9368252 TI - Disorders of coagulation misdiagnosed as nonaccidental bruising. AB - Two cases of idiopathic thrombocytopenia and one case of hemophilia with unexplained bruising are presented. The children were all initially thought to be victims of nonaccidental trauma until coagulation disorder screening tests were returned with abnormal values. A review of the literature of similar cases is presented. It is recommended that any child with unexplained or implausible bruising receive a screen for coagulation disorders consisting of a complete blood count with platelet count, prothrombin time, a partial thromboplastin time, and a bleeding times. PMID- 9368253 TI - Drug-drug interactions and the cytochrome P450 system: an update. PMID- 9368254 TI - To treat or not to treat: if so, with what? PMID- 9368255 TI - Sore wrist after fall. PMID- 9368256 TI - Asthma among inner city children. PMID- 9368257 TI - Psychosocial influences on asthma among inner-city children. PMID- 9368258 TI - Design and methods of the National Cooperative Inner-City Asthma Study. AB - The National Cooperative Inner-City Asthma Study (NCICAS) was established to identify and then intervene on those factors which are related to asthma morbidity among children in the inner-city. This paper describes the design and methods of the broad-based initial Phase I epidemiologic investigation. Eight research centers enrolled 1,528 children, 4 to 9 years of age, from English- or Spanish-speaking families, all of whom resided in major metropolitan inner-city areas. The protocol included an eligibility assessment and an extensive baseline visit, during which symptom data, such as wheezing, lost sleep, changes in activities of daily living, inpatient admissions, and emergency department and clinic visits were collected. A comprehensive medical history for each child was taken and adherence to the medical regimen was assessed. Access, as well as barriers, to the medical system were addressed by a series of questions including the location, availability, and consistency of treatment for asthma attacks, follow-up care, and primary care. The psychological health of the caretaker and of the child was also measured. Asthma knowledge of the child and caretaker was determined. Sensitization to allergens was assessed by skin-prick allergen testing and exposure to cigarette smoke and the home environment were assessed by questionnaire. For more than a third of the families, in-home visits were conducted with dust sample allergen collection and documentation of the home environment, such as the presence of pets and evidence of smoking, mildew, and roaches. Urine specimens were collected to measure passive smoke exposure by cotinine assays, blood samples were drawn for banking, and children age 6 to 9 years were given spirometric lung function assessment. At 3, 6 and 9 months following the baseline assessment, telephone interviews were conducted to ask about the child's symptoms, unscheduled emergency department or clinic visits, and hospitalizations. At this time, peak flow measurements with 2-week diary symptom records were collected. PMID- 9368259 TI - Characteristics of inner-city children with asthma: the National Cooperative Inner-City Asthma Study. AB - Asthma morbidity has increased dramatically in the past decade, especially among poor and minority children in the inner cities. The National Cooperative Inner City Asthma Study (NCICAS) is a multicenter study designed to determine factors that contribute to asthma morbidity in children in the inner cities. A total of 1,528 children with asthma, ages 4 to 9 years old, were enrolled in a broad-based epidemiologic investigation of factors which were thought to be related to asthma morbidity. Baseline assessment included morbidity, allergy evaluation, adherence and access to care, home visits, and pulmonary function. Interval assessments were conducted at 3, 6, and 9 months after the baseline evaluations. Over the one year period, 83% of the children had no hospitalizations and 3.6% had two or more. The children averaged 3 to 3.5 days of wheeze for each of the four two-week recall periods. The pattern of skin test sensitivity differed from other populations in that positive reactions to cockroach were higher (35%) and positive reactions to house dust mite were lower (31%). Caretakers reported smoking in 39% of households of children with asthma, and cotinine/creatinine ratios exceeded 30 ng/mg in 48% of the sample. High exposure (> 40 ppb) to nitrogen dioxide was found in 24% of homes. Although the majority of children had insurance coverage, 53% of study participants found it difficult to get follow-up asthma care. The data demonstrate that symptoms are frequent but do not result in hospitalization in the majority of children. These data indicate a number of areas which are potential contributors to the asthma morbidity in this population, such as environmental factors, lack of access to care, and adherence to treatment. Interventions to reduce asthma morbidity are more likely to be successful if they address the many different asthma risks found in the inner cities. PMID- 9368260 TI - Psychosocial characteristics of inner-city children with asthma: a description of the NCICAS psychosocial protocol. National Cooperative Inner-City Asthma Study. AB - Previous research has demonstrated a significant reciprocal relationship between psychosocial factors and asthma morbidity in children. The National Cooperative Inner-City Asthma Study investigated both asthma-specific and non-specific psychosocial variables, including asthma knowledge beliefs and management behavior, caregiver and child adjustment, life stress, and social support. This article presents these psychosocial characteristics in 1,528 4-9-year-old asthmatic urban children and their caretakers. Caretakers demonstrated considerable asthma knowledge, averaging 84% correct responses on the Asthma Information Quiz. However, respondents provided less than one helpful response for each hypothetical problem situation involving asthma care, and most respondents had more than one undesirable response, indicating a potentially dangerous or maladaptive action. Both adults and children reported multiple caretakers responsible for asthma management (adult report: average 3.4, including the child); in addition, children rated their responsibility for self care significantly higher than did adults. Scores on the Child Behavior Checklist indicated increased problems compared to normative samples (57.3 vs. 50, respectively), and 35% of children met the criteria for problems of clinical severity. On the Brief Symptom Inventory, adults reported elevated levels of psychological distress (56.02 vs norm of 50); 50% of caretakers had symptoms of clinical severity. Caretakers also experienced an average of 8.13 undesirable life events in the 12 months preceding the baseline interview. These findings suggest that limited asthma problem-solving skills, multiple asthma managers, child and adult adjustment problems, and high levels of life stress are significant concerns for this group and may place the inner-city children in this study population at increased risk for problems related to adherence to asthma management regimens and for asthma morbidity. PMID- 9368261 TI - Lung function in infants with sickle cell disease. AB - We performed pulmonary function testing in 20 infants (11 male and 9 female; ages 3-30 months) with sickle cell disease to assess whether abnormal lung function develops early in life. Respiratory system compliance (Crs) and resistance (Rrs) were measured by the passive occlusion technique, functional residual capacity (FRC) was measured by the nitrogen washout technique, and tidal flow-volume loops and partial expiratory flow-volume curves were obtained by the thoracoabdominal compression technique to detect airway obstruction. Patients with Hb SS (Group I, n = 12) had significantly lower hemoglobin levels and a higher (but not significant) incidence of acute chest syndrome (ACS), vasoocclusive crisis (VOC), splenic sequestration, transfusions, and history of intermittent bronchospasm compared to with patients with hemoglobinopathies Hb SC, Hb Sbt and Hb SF (Group II; n = 8). Both groups had elevated FRC, decreased maximum expiratory flows at FRC (V'max,FRC), and decreased time needed to reach peak expiratory flow (tme/tE), suggesting lower airway obstruction (LAO) and hyperinflation. Restrictive disease was found in only three patients of Group I. Our findings suggest that in sickle cell disease (especially among patients with Hb SS), abnormal lung function (predominantly LAO) may be present in early infancy. Airway reactivity may play a role in the pathogenesis, but the relation to VOC or ACS remains unclear. PMID- 9368262 TI - Jet nebulization of budesonide suspension into a neonatal ventilator circuit: synchronized versus continuous nebulizer flow. AB - To determine the dose of inhaled budesonide suspension in the treatment of preterm infants with ventilator-dependent lung disease, we measured the dose of nebulized budesonide delivered through an endotracheal tube (ETT), using a test lung and filters. The effect of delivering the nebulized aerosol to two different locations in the same ventilatory circuit was evaluated. In addition, a new synchronized jet nebulizer was tested. The median drug delivery to the test lung was 0.3% (range, 0-0.4%) of the nominal dose when the nebulizer activated by continuous gas flow was inserted into the inspiratory line of the circuit. Drug delivery could be increased to 0.7% (range, 0.5-0.8%) by delivering the nebulizer output directly to the ETT. When using the synchronized jet nebulizer, drug delivery was 1.1% (range, 0.8-1.6%). The particle size of aerosol emerging from the ETT was 2.14 microns. The nebulization time with the synchronized nebulizer set-up was 38 min, while the other set-ups delivered an equal volume of solution in 6-7 min. Drug delivery of 0.3-1.1% to the test lung illustrates the problems encountered in aerosol treatment of intubated neonates. We conclude that the delivery of budesonide to the test lung can be increased by delivering the nebulizer output to the ETT directly. Using synchronized nebulization during inspiration only can achieve further increases in drug delivery, and wastage of drug during expiration is decreased. Synchronized nebulization may, therefore, have an important place in the delivery of expensive aerosolized drugs. PMID- 9368263 TI - Mediastinal lymphadenopathy caused by Mycobacterium avium-intracellulare complex in a child with normal immunity: successful treatment with anti-mycobacterial drugs and laser bronchoscopy. AB - We report on the case of a 9-month-old Caucasian girl referred to our institution with a history of fever of unknown origin and wheezing, unresponsive to bronchodilator and anti-inflammatory therapy. Subsequent investigation led to a diagnosis of mediastinal lymphadenopathy caused by Mycobacterium avium intracellulare (MAI). The infected lymph tissue infiltrated and obstructed the right bronchus and significantly compressed the left bronchus to the point of near closure. Given the high degree of morbidity and potential mortality from thoracic surgery in this patient, we treated her with a combination of anti mycobacterial drugs (rifabutin, clarithromycin, ciprofloxacin, clofazimine, amikacin, ethambutol) and glucocorticoids to relieve airway compression. The endobronchial granulation tissue was resected by laser bronchoscopy. This combined approach led to eventual normalization of radiologic and endoscopic findings, and the anti-mycobacterial chemotherapy was discontinued 12 months after the first bronchoalveolar lavage culture was negative for MAI. The patient remains asymptomatic 1 year after completion of this course of therapy. We suggest that mediastinal lymphadenopathy with bronchial infiltration and extrinsic airway compression caused by MAI in otherwise healthy children can be successfully treated with aggressive chemotherapy, glucocorticoids, and laser bronchoscopy. PMID- 9368264 TI - Pulmonary alveolar proteinosis in an HIV-infected child. PMID- 9368266 TI - Acquired pulmonary cyst in the newborn infant. PMID- 9368265 TI - Urticaria associated with the pilocarpine iontophoresis sweat test. PMID- 9368267 TI - Chloral hydrate and sleep deprivation for sedation during flexible fiberoptic bronchoscopy. PMID- 9368269 TI - Current concepts in the embryology of anorectal malformations. AB - Today, the normal and abnormal development of the hindgut is still a matter of speculation. However, owing to recent studies in appropriate animal models, most embryological events that finally lead to abnormal hindgut development are better known than in the past: (1) The process of maldevelopment starts early in the embryo. (2) The cloacal membrane always is too short in its dorsal part. Thus the dorsal cloaca is missing too. (3) As a result, the hindgut remains attached to the sinus urogenitalis, thus forming the recto-urethral fistula. In the past, an impaired process of septation was believed to be the main cause of abnormal hindgut development. In contrast to this, our results indicate that the development of the septum is more passive than active. Further results of our studies in normal and abnormal development indicate that (1) the embryonic cloaca never passes through a stage that is similar to any form of anorectal malformation in neonates, including the so-called "cloacas" in females, and (2) to explain abnormal development, studies in abnormal embryos are mandatory. PMID- 9368268 TI - The genetics of anorectal malformations: a complex matter. AB - Because the spectrum of anorectal malformations is wide, genetic investigations of these anomalies should include the study of multigenic models presenting variable penetrance and expressivity. Current knowledge in clinical genetics, cytogenetics, and molecular genetics of anorectal anomalies are reviewed. The analysis of associated anomalies (that are found in more than 60% of anorectal malformations) is an important aspect of the molecular study, because the association of anomalies with mendelian transmission or with a recognized causative gene can be an essential starting point for further investigations. In the present study, the authors focus on associated sacral anomalies, urethral malformations, and intestinal dysganglionoses. In particular, associated sacral anomalies could be a partial expression of the Currarino syndrome, which represents the only association for which genetic evidence has been demonstrated by linkage analysis. The authors studied a four-generation pedigree with recurrence of the Currarino syndrome, and the haplotype reconstruction confirmed that the gene segregating in this family is located in the 7q36 region. The collection and study of families with multiple cases of anorectal malformations could show whether different phenotypes are caused by single genes. PMID- 9368270 TI - Classification of anorectal malformations--initial approach, diagnostic tests, and colostomy. AB - The optimal surgical care of patients with imperforate anus begins with appropriate decision making in the critical newborn period. In most cases the decision to create a colostomy should be delayed until the infant is 18 to 24 hours old. Except in cases of a rectoperineal fistula, most neonates are best treated with a completely divided left-lower-quadrant colostomy between the descending and sigmoid colons. Female patients with cloacal anomalies must be recognized at birth so that all urgent urologic evaluations can be performed. Hydrocolpos and obstructive uropathy are common in these neonates and warrant urgent decompression of the urinary tract with a vaginostomy and/or vesicostomy as well as a colostomy. Renal ultrasonography and voiding cystourethrography are mandatory for all patients regardless of the height of the defect. It is critical to discover the important precursors to renal insufficiency including renal agenesis, renal dysplasia, and vesicoureteral reflux in the neonate. The presence of these anomalies mandates early consultation with a pediatric urologist because the morbidity and mortality of these lesions often exceed those of the imperforate anus. Spinal cord anomalies are common and can be found even in patients who have normal plain films and low defects. Spinal ultrasonography or magnetic resonance imaging should be performed in all neonates to rule out occult spinal pathology such as tethered cord or lipoma of the cord. Efficacious and cost-effective care of patients with imperforate anus begins with a carefully thought out plan in the neonate. Optimal execution of the evaluation and surgical treatment at this phase sets the stage for the best possible outcome later in life. PMID- 9368271 TI - The anterior sagittal approach to the treatment of anorectal malformations: evolution of the Mollard approach. AB - Mollard's anterior perineal approach has been used for more than 20 years for the treatment of anorectal malformations and has undergone several modifications. The anterior sagittal approach is a simplification of the Mollard approach. It allows a safe dissection and preservation of the puborectalis sling, a clear identification of the external sphincters and other striated muscle fibers caudal to the puborectalis, and prevents inadvertent damage to the nerve supply. The site of the rectourethral (or rectovaginal) fistula, containing the internal sphincter, is preserved for anastomosis with the anoderm. The rectal cul-de-sac is mobilized minimally to come through the puborectalis under some tension, while the anoderm and external sphincters are also brought up under tension to meet these structures, thereby creating a short anal canal more closely resembling the normal anatomy. This approach can be used for most types of anorectal malformations in both sexes, and usually is combined with a transverse suprapubic laparotomy for supralevator anomalies. PMID- 9368272 TI - The surgical treatment of low anal defects and vestibular fistulas. AB - A series of 227 patients with what are traditionally known as "low" anorectal malformations (ARM) are presented. Perineal fistulas (PF; n = 108), anterior perineal anus (APA; n = 22), and vestibular fistulas (VF; n = 97) represented 73% of the 309 patients with ARM operated on primarily. Diagnosis was based on perineal inspection. In cases of PF and APA, the rectum opens at the perineal skin, anterior to the normal site. Associated malformations were found in 23% of patients with PF and in 13% of patients with APA. Anoplasty without a colostomy was performed in patients with PF. Normal continence was achieved in 93.3%, and constipation occurred in 47%. In patients with APA and intractable constipation, a partial sphincterotomy relieved painful evacuations in 96%. VF is not a low defect; the rectum opens in the vaginal introitus, and dissection of the rectovaginal common wall is necessary for reconstruction. In neonates with VF, the authors performed a sigmoid colostomy followed by a limited posterior sagittal anorectoplasty at 2 months of age. Of the 97 patients with VF, associated malformations were found in 57%. Continence was evaluated in 67 patients with repaired VF. Normal continence was found in 71% and constipation in 50%. Only one patient with VF experienced severe complications and incontinence, after surgical mismanagement. Precise clinical diagnosis and meticulous surgical technique are essential in the management of these benign malformations. PMID- 9368273 TI - Management of cloacal malformations. PMID- 9368274 TI - Fecal incontinence in children with anorectal malformations. AB - Children with anorectal malformations suffer from postoperative fecal incontinence as well as other forms of defecation disorders such as constipation, soiling, and incontinence associated with episodes of diarrhea. Indiscriminate use of laxatives, enemas, and pharmacotherapy is not recommended. Rather, it is possible to systematically diagnose and manage fecal incontinence after reconstruction for anorectal malformations. Three groups of children have been identified: candidates for reoperation, candidates for a bowel management program, and pseudoincontinent children. Postoperative evaluation for fecal incontinence should include accurate identification of the type of anorectal anomaly and knowledge of the original reconstructive procedure. In addition, history, physical examination, and review of radiological studies are mandatory, with detailed attention paid to the status of the striated external sphincter musculature and sacrum. Children then can be managed based on the type of fecal incontinence from which they suffer. Bowel management is successful only when performed in an organized manner, and it is recommended as an outpatient procedure. PMID- 9368276 TI - Preparticipation screening of children for sports. Current recommendations. AB - Every year physicians all over the world are asked to perform preparticipation physical evaluations (PPE) for children involved in sports. The PPE should be brief yet comprehensive enough to determine which athletes are at risk. In addition, the examination may help determine the athlete's general health and maturity level, uncover any disqualifying conditions and may also help establish a doctor-patient relationship. PPEs should be performed 4 to 6 weeks prior to initiation of the sport and be repeated every 1 to 3 years. A station-based exam may help evaluate large numbers of athletes within a limited time period. The history is the most important aspect of the PPE and should focus on prior cardiovascular complications, a family history of cardiovascular death before 50 years of age and any other limiting medical problems. A general physical examination should be performed to focus on areas involved in sports participation. Laboratory tests are not usually necessary. Disqualifying conditions may be determined based on the physical abnormality present and the amount of contact or energy involved in the sport to be played. Throughout the world, sports participation is growing rapidly. Although these guidelines have been drafted by a consortium of sports-related and general practice groups in the US, they can easily be applied worldwide. Unfortunately the health of young adults in developing countries may not be as good as that of those residing in more industrialised countries, therefore each athlete must be considered individually. With this type of individualised approach the examining physician can make informed and intelligent decisions concerning the athlete's participation. PMID- 9368275 TI - Flexibility and its effects on sports injury and performance. AB - Flexibility measures can be static [end of ROM (range of motion)], dynamic passive (stiffness/compliance) or dynamic-active (muscle contracted, stiffness/compliance). Dynamic measures of flexibility are less dependent on patient discomfort and are more objective. Acute and chronic changes in flexibility are likely to occur with stretching exercises, but it is difficult to distinguish between changes in stretch tolerance as opposed to changes in muscle stiffness. How flexibility is measured impacts these findings. There is no scientifically based prescription for flexibility training and no conclusive statements can be made about the relationship of flexibility to athletic injury. The literature reports opposing findings from different samples, frequently does not distinguish between strain, sprain and overuse injury, and rarely uses the proper denominator of exposure. There is basic scientific evidence to suggest that active warm-up may be protective against muscle strain injury but clinical research is equivocal on this point. Typically, specific flexibility patterns are associated with specific sports and even positions within sports. The relationship of flexibility to athletic performance is likely to be sport dependent. Decreased flexibility has been associated with increased in-line running and walking economy. Increased stiffness may be associated with increased isometric and concentric force generation, and muscle energy storage may be best manifested by closely matching muscle stiffness to the frequency of movement in stretch-shorten type contractions. PMID- 9368277 TI - Determinants of oxygen uptake. Implications for exercise testing. AB - For exercise modalities such as cycling which recruit a substantial muscle mass, muscle oxygen uptake (VO2) is the primary determinant of pulmonary VO2. Indeed, the kinetic complexities of pulmonary VO2 associated with exercise onset and the non-steady state of heavy (> lactate threshold) and severe [> asymptote of power time relationship for high intensity exercise (W)] exercise reproduce with close temporal and quantitative fidelity those occurring across the exercising muscles. For moderate (< lactate threshold) exercise and also rapidly incremental work tests, pulmonary (and muscle) VO2 increases as a linear function of work rate (approximately equal to 9 to 11 ml O2/W/min) in accordance with theoretical determinations of muscle efficiency (approximately equal to 30%). In contrast, for constant load exercise performed in the heavy and severe domains, a slow component of the VO2 response is manifest and pulmonary and muscle VO2 increase as a function of time as well as work rate beyond the initial transient associated with exercise onset. In these instances, muscle efficiency is reduced as the VO2 cost per unit of work becomes elevated, and in the severe domain, this VO2 slow component drives VO2 to its maximum and fatigue ensues rapidly. At pulmonary maximum oxygen uptake (VO2max) during cycling, the maximal cardiac output places a low limiting ceiling on peak muscle blood flow, O2 delivery and thus muscle VO2. However, when the exercise is designed to recruit a smaller muscle mass (e.g. leg extensors, 2 to 3kg), mass-specific muscle blood flow and VO2 at maximal exercise are 2 to 3 times higher than during conventional cycling. consequently, for any exercise which recruits more than approximately equal to 5 to 6kg of muscle at pulmonary VO2max, there exists a mitochondrial or VO2 reserve capacity within the exercising muscles which cannot be accessed due to oxygen delivery limitations. The implications of these latter findings relate to the design of exercise tests. Specifically, if the purpose of exercise testing is to evaluate the oxidative capacity of a small muscle mass (< 5 to 6kg), the testing procedure should be designed to restrict the exercise to those muscles so that a central (cardiac output, muscle O2 delivery) limitation is not invoked. It must be appreciated that exercise which recruits a greater muscle mass will not stress the maximum mass-specific muscle blood flow and VO2 but rather the integration of central (cardiorespiratory) and peripheral (muscle O2 diffusing capacity) limitations. PMID- 9368279 TI - Subtalar ankle instability. A review. AB - The aetiology of chronic functional lateral ankle instability is fairly well understood. Pathophysiological factors such as mechanical instability, proprioceptive deficit and peroneal muscle weakness have been demonstrated. Subtalar instability has been in focus during the last years as one of the possible factors behind chronic functional instability of the foot. The exact aetiology and the true incidence of subtalar ligament injuries remain unknown. Most subtalar ligamentous injuries probably occur in combination with injuries of the talo-tibial articulation. Subtalar instability can have the characteristics of chronic lateral instability or recurrent ankle sprains. Patients with chronic subtalar instability typically complain of 'giving way' symptoms and a history of recurrent sprains. Clinical examination including increased inwards rotation and forward displacement of the calcaneus may not be sufficient for the differentiation between ankle and subtalar instability. Radiographic imaging using stress radiographs may be necessary to assess subtalar instability. Subtalar instability can be defined as chronic functional instability with increased values of talar tilt and talo-calcaneal displacement as measured with standardised stress radiographs. Few authors have addressed the treatment of subtalar instability and the condition has not been clearly defined. Subtalar instability can be treated either with a tendon transfer or tenodesis procedure, such as the Chrisman-Snook or triligamentous tenodeses, or with an anatomic ligament reconstruction using the calcaneo-fibular, lateral talo-calcaneal and cervical ligaments combined with a reinforcement of the inferior extensor retinaculum. There have been no studies comparing anatomical and non-anatomical reconstructions and the long term results after ligamentous stabilisation are unknown. The focus of this article is on subtalar instability causing chronic functional ankle instability. PMID- 9368280 TI - Rehabilitation of tendon injuries in sport. AB - Clinicians are faced with a growing number of athletes with injured tendons. Treatment of both acute and chronic injuries has proven to be quite complex. It is difficult to maintain the balance between resting the injured tendon and preventing atrophy of the surrounding muscles and joints. Questions also arise as to when the tendon should be strengthened and when the athlete is ready to return to full activity in sport. Through an awareness of the structural and mechanical properties of the tendon, an exercise programme for the rehabilitation of tendon injuries has been developed. It is recommended that this programme be used in combination with ice and other physical modalities. This approach will resolve most tendon injuries within 6 weeks of its implementation. The use of anti inflammatory medications and surgery can only be recommended in select situations where more conservative measures are inadequate. PMID- 9368281 TI - Mechanisms of radiation injury: impact of molecular medicine. PMID- 9368282 TI - An overview of molecular abnormalities leading to thyroid carcinogenesis: a 1993 perspective. AB - This discussion reviews molecular abnormalities in thyroid carcinoma and points out areas where these molecular defects might be applicable to thyroid carcinogenesis induced by radiation exposure. Both medullary and papillary follicular thyroid carcinoma are discussed. The multiple endocrine neoplasia type 2 gene on chromosome 10 is one of the genes responsible for medullary thyroid carcinoma. Genes thought to be involved in papillary and follicular thyroid carcinoma include the gsp, ret, trk, ras, met, and p53 oncogenes. Research is continuing to: A) find new genes whose regulation and/or expression may be responsible for these disorders; B) determine the mechanisms by which gene mutations can lead to thyroid carcinogenesis, and C) devise methods to prevent or counter the effects of these mutational events. PMID- 9368278 TI - Role of exercise training in the prevention and treatment of insulin resistance and non-insulin-dependent diabetes mellitus. AB - Recent epidemiological studies indicate that individuals who maintain a physically active lifestyle are much less likely to develop impaired glucose tolerance and non-insulin-dependent diabetes mellitus (NIDDM). Moreover, it was found that the protective effect of physical activity was strongest for individuals at highest risk of developing NIDDM. Reducing the risk of insulin resistance and NIDDM by regularly performed exercise is also supported by several aging studies. It has been found that older individuals who vigorously train on a regular basis exhibit a greater glucose tolerance and a lower insulin response to a glucose challenge than sedentary individuals of similar age and weight. While the evidence is substantial that aerobic exercise training can reduce the risk of impaired glucose tolerance and NIDDM, the evidence that exercise training is beneficial in the treatment of NIDDM is not particularly strong. Many of the early studies investigating the effects of exercise training on NIDDM could not demonstrate improvements in fasting plasma glucose and insulin levels, or glucose tolerance. The adequacy of the training programmes in many of these studies, however, is questionable. More recent studies using prolonged, vigorous exercise training protocols have produced more favourable results. There are several important adaptations to exercise training that may be beneficial in the prevention and treatment of insulin resistance, impaired glucose tolerance and NIDDM. An increase in abdominal fat accumulation and loss of muscle mass are highly associated with the development of insulin resistance. Exercise training results in preferential loss of fat from the central regions of the body and should therefore contribute significantly in preventing or alleviating insulin resistance due to its development. Likewise, exercise training can prevent muscle atrophy and stimulate muscle development. Several months of weight training has been found to significantly lower the insulin response to a glucose challenge without affecting glucose tolerance, and to increase the rate of glucose clearance during a euglycaemic clamp. Muscle glucose uptake is equal to the product of the arteriovenous glucose difference and the rate of glucose delivery or muscle blood flow. While it has been known for many years that insulin will accelerate blood glucose extraction by insulin-sensitive peripheral tissues, recent evidence suggests that it can also acutely vasodilate skeletal muscle and increase muscle blood flow in a dose-dependent manner. A reduced ability of insulin to stimulate muscle blood flow is a characteristic of insulin-resistant obese individuals and individuals with NIDDM. Exercise training, however, has been found to help alleviate this problem, and substantially improve the control of insulin over blood glucose. Improvements in insulin resistance and glucose tolerance with exercise training are highly related to an increased skeletal muscle insulin action. This increased insulin action is associated with an increase in the insulin-regulatable glucose transporters, GLUT4, and enzymes responsible for the phosphorylation, storage and oxidation of glucose. Changes in muscle morphology may also be important following training. With exercise training there is an increase in the conversion of fast twitch glycolytic IIb fibres to fast twitch oxidative IIa fibres, as well as an increase in capillary density. IIa fibres have a greater capillary density and are more insulin sensitive and -responsive than IIb fibres. Evidence has been provided that morphological changes in muscle, particularly the capillary density of the muscle, are associated with changes in fasting insulin levels and glucose tolerance. Furthermore, significant correlations between glucose clearance, muscle capillary density and fibre type have been found in humans during a euglycaemic clamp. Exercise training may also improve control over hepatic glucose production by increasin PMID- 9368283 TI - Mechanisms of radiation-induced gene responses. AB - While identifying genes differentially expressed in cells exposed to ultraviolet radiation, we identified a transcript with a 25-nucleotide region that is highly conserved among a variety of species, including Bacillus circulans, pumpkin, yeast, Drosophila, mouse, and man. In the 5' untranslated region of a gene, the sequence is predominantly in a +/+ orientation with respect to the coding DNA strand; while in the coding region and the 3' untranslated region, the sequence is most frequently in a -/+ orientation. The element is found in many different genes that have diverse functions. Gel mobility shift assays demonstrated the presence of a protein in HeLa cell extracts that binds to the sense and antisense single-stranded consensus oligomers, as well as to double-stranded oligonucleotide. When double-stranded oligomer was used, the size shift demonstrated an additional protein-oligomer complex larger than the one bound to either sense or antisense single-stranded consensus oligomers alone. This element may bind to protein(s) that maintain DNA in a single-stranded orientation for transcription, or be important in the transcription-coupled DNA repair process. PMID- 9368284 TI - Damage-sensing mechanisms in human cells after ionizing radiation. AB - Human cells have evolved several mechanisms for responding to damage created by ionizing radiation. Some of these responses involve the activation or suppression of the transcriptional machinery. Other responses involve the downregulation of enzymes, such as topoisomerase I, which appear to be necessary for DNA repair or apoptosis. Over the past five years, many studies have established links between DNA damage, activation of transcription factors that are coupled to DNA repair mechanisms, increased gene transcription and altered cell cycle regulation to allow for repair or cell death via apoptosis or necrosis. Together these factors determine whether a cell will survive with or without carcinogenic consequences. The immediate responses of human cells to ionizing radiation, in terms of sensing and responding to damage, are therefore, critical determinants of cell survival and carcinogenesis. PMID- 9368285 TI - Differential inhibition of radiation-induced apoptosis. AB - The most common mechanism by which radiation kills cells is the induction of DNA double-strand breaks that results in the loss of cell proliferation. Even though apoptosis is increasingly identified in experimental systems in vitro and in vivo, it is still generally regarded as a rare mode of radiation-induced cell kill with minor relevance for the clinical effects of radiation. This review will focus on pro- and antiapoptotic signaling that affects the apoptotic outcome in irradiated mammalian cells. In particular, we will concentrate on the sphingomyelin/ceramide signal transduction pathway which is involved in initiation of stress-induced apoptosis in a variety of normal and neoplastic cells. We will also discuss the crosstalk between the sphingomyelin/ceramide pathway and the protein kinase C pathway which constitutes an antiapoptotic pathway, and the potential for pharmacological modulation to increase the fraction of apoptotic cells undergoing apoptosis after radiation exposure. PMID- 9368286 TI - Early plasma membrane events occurring in ultraviolet-B-induced apoptosis. AB - Whereas nonsolar ultraviolet C radiation primarily affects nuclei (i.e., where it is absorbed by nucleic acids) of eukaryotic cells, ultraviolet radiation of long (320-380 nm) wavelengths (ultraviolet A) and intermediate (290-320 nm) wavelengths (ultraviolet B) primarily affects lipid membranes. We have previously demonstrated that ultraviolet B irradiation alters the surface architecture of human B cells and impairs expression of an erythroid growth factor on their surface and on extracellular vesicles. Here, we examined the effects of ultraviolet B irradiation on the capacity of Chinese hamster ovary cells to undergo the process of exfoliation, and on the capacity of Chinese hamster ovary cells transfected with flt3/flk2 cDNA to express the cytokine flt3/flk2. Our results indicate that the rate of release of shed vesicles from untransfected Chinese hamster ovary cells is decreased after one to two h, at a time when there is electron microscopic evidence for retention of vesicles at the cell surface. These changes at the cell surface precede all other apparent morphological changes (including DNA condensation in the nucleus, swelling of the mitochondria and appearance of apoptotic bodies). Furthermore, plasma membranes and shed extracellular vesicles from ultraviolet B irradiated Chinese hamster ovary cells that have been transfected with flt3/flk2 cDNA fail to express the protein. PMID- 9368287 TI - Oxidative stress, signal transduction, and intercellular communication in radiation carcinogenesis. AB - During the evolution of multicellular organisms, survival in an aerobic environment came about by adaptive responses, both to the endogenous oxidative metabolism within the cells of the organism as well as the chemicals and low level radiation to which they are exposed. In addition to defense mechanisms shared with single-cell organisms, multicellular organisms are equipped with gap junctions which allow electrotonic and/or metabolic synchronization of processes between coupled cells. The connexin genes, which code for the proteins comprising the gap junctions, provide homeostatic regulation of cell proliferation, differentiation, and adaptive responses of individual cells through a mechanism of "gap junctional intercellular communication." The biological consequences of the response of a multicellular organism to low-level radiation exceeding the background level of oxidative damage to a cell in a tissue could be apoptosis, cell proliferation, or cell differentiation. PMID- 9368288 TI - Radiation damage to hematopoiesis: what do we know better? PMID- 9368289 TI - Practical and theoretical issues in 1993 concerning radiation effects on the growth of normal and neoplastic hematopoietic cells. AB - Radiation has multiple effects on eukaryotic cells, ranging from altered gene expression and cell-cell signaling to induction of programmed cell death (i.e., apoptosis). These changes may lead to neoplastic transformation of the cell and diverse effects on differentiation and growth. The Belarusians were exposed to greater levels of radiation from the Chernobyl nuclear reactor melt-down than any other population. Medical consequences of this exposure are reviewed, focusing on the appearance of thyroid cancer and the possible increased risk of future hematologic malignancies. Since circulating hematopoietic cells must be relaced continually at high rates, the effects of ionizing radiation are reviewed at the cellular level, utilizing the hematopoietic system as a model tissue. An overview of normal hematopoiesis (as understood in 1993) is provided, and the effects of ionizing radiation on hematopoietic stem cell compartments are reviewed. Hematopoietic growth factors (i.e., cytokines) that are associated with the plasma membrane (i.e., membrane-bound cytokines), or that are released as "soluble" molecules into the microenvironment and circulation, may "protect" organisms from radiation injury and may accelerate hematopoietic recovery following radiation exposure. Cloned hematopoietic cytokines, individually or in combination, may be useful in the treatment of radiation accident victims in the future. PMID- 9368290 TI - Modulation of radiation damage by cytokines. AB - Cytokines, hormone-like proteins that are produced by stimulated cells and tissues, serve as intercellular messengers. The production of an expanding number of recombinant cytokines in pharmacological quantities has permitted an assessment of the benefit they may provide in preserving and restoring functions of tissues compromised by irradiation. Included here are studies indicating that the cytokines interleukin 1, tumor necrosis factor, stem cell factor and interleukin 12 protect mice from radiation lethality when given prior to irradiation, and even in untreated mice these cytokines serve in innate defenses against external stimuli. In contrast, transforming growth factor beta, interleukin 6 and interferon, given before irradiation, sensitize the mice to radiation lethality. Myeloprotection against ionizing radiation and chemotherapeutic drugs by interleukin 1 depends on the regimen of treatment and may be related to the temporary patterns of induced cytokines and to the resulting changes in the cycling status of the progenitor cells. Interleukin 12, through induction and interaction with additional cytokines, has contrasting effects on different tissues, i.e., protecting the bone marrow but sensitizing the gut. Insights gained from such studies into the cellular mechanisms of regulation of radiation-induced damage by cytokines are discussed. Whether a "trade-off" of protection of some tissues and sensitization of other tissues applies to cytokine therapy in humans is unknown. PMID- 9368291 TI - Abrogation of radiation injury to human hematopoietic stem cells with tumor necrosis factor-alpha. AB - Ionizing radiation kills hematopoietic stem and progenitor cells. However, several cytokines, including tumor necrosis factor-alpha (TNF-alpha), protect the murine hematopoietic system if they are introduced before or immediately after irradiation. We examined the in vitro capacity of TNF-alpha to protect human hematopoietic stem cells and early progenitor cells from x-ray-induced death. Human CD34+ cells obtained from normal bone marrow were highly enriched for stem and progenitor cells. Pulse exposure of these cells to human TNF-alpha during the first hour immediately after x irradiation (doses of 0.45 Gy to 9 Gy) significantly improved further survival of true hematopoietic stem cells and early progenitors and the ability of CD34+ cells to produce mature hematopoietic cells in liquid culture with hematopoietic growth factors. The radioprotective effect of TNF-alpha was stronger at lower doses, when complete restoration of hematopoiesis was often observed. In contrast, the radioprotective effect of TNF alpha was moderate at higher doses, with neither complete restoration of the number of stem and progenitor cells nor the production of mature cells. Our data suggest that TNF-alpha can protect human hematopoietic stem and early progenitor cells from ionizing radiation. PMID- 9368292 TI - Use of computer TV morphodensitometry to study epigenetic changes in blood lymphocytes from children affected by low-dose irradiation. AB - A novel method, computer TV morphodensitometry, was used to evaluate the effects of low-dose irradiation on peripheral blood lymphocytes from children affected by the Chernobyl disaster. This method uses digitized images to detect and measure changes in chromatin shape and density and to produce two-dimensional and three dimensional pictures. Images can then be stored to create a video archive. This method is sensitive enough to observe subtle changes in chromatin structure that previously could be detected only by more detailed molecular analyses. In this study, lymphocyte interphase nuclei in DNA-stained blood smears from children subjected to chronic low-dose irradiation were examined by computer TV morphodensitometry. Preliminary data indicate that circulating lymphocytes from children exposed to radiation may contain significant alterations in the structure and/or density of nuclear chromatin. PMID- 9368293 TI - Radioprotective and antileukemic effects of growth factors in regenerating hematopoietic tissue. AB - We have examined the role of growth factors present in regenerating hematopoietic tissue in the prevention of some radiation-induced effects. These factors, extracted from calf spleen undergoing reparative regeneration, increased the 30 day survival of irradiated mice and partially decreased the incidence of leukemia in surviving mice. The growth factors modified the properties of leukemia cells in vitro, and could suppress residual leukemia cells in vivo. The antileukemic activity of regenerating hematopoietic tissue can be purified to a homogeneous state. The radioprotective activity is associated with the production of regulatory molecules that have been partially characterized. These findings provide evidence that the natural resistance of regenerating hematopoietic tissue (which has an increased number of cell targets for radiation and other damaging agents) results from concurrent local production of a battery of defensive regulatory molecules. PMID- 9368294 TI - A perspective on clinical disorders of radiation accident victims. PMID- 9368295 TI - The Chernobyl catastrophe and population health: the state of knowledge in 1993. AB - This review describes the history and organizational structure of the Ukrainian Research Center for Radiation Medicine, which has studied the health effects of the Chernobyl incident since 1986. In five years of observation, the percentage of people defined as "healthy" was reduced by 1.6-2.2 times, and the general frequency of disease increased by 2.6 times. The most common disorders seen were of the pulmonary, central nervous system, circulatory and gastrointestinal systems. The observed medical effects of radiation from Chernobyl are greater than might be expected, given the estimates of radiation dose released. This discrepancy may result from an underestimation of the radiation dose or a failure to account for compounding the interaction with factors other than radiation. Ongoing surveillance of the consequences from the Chernobyl accident must take place to provide new information on the health effects of accidental radiation exposure in humans. PMID- 9368297 TI - Leukemia: lessons from the Japanese experience. AB - Probably more has been learned about radiation-induced leukemia from intensive study of Japanese atomic bomb survivors than about radiation damage to any other organ system. This has been the result of an intensive binational effort at the Atomic Bomb Casualty Commission and the Radiation Effects Research Foundation in Hiroshima and Nagasaki to monitor the occurrence of leukemia in a large group of atomic bomb survivors over a period of more than 50 years (the Life Span Study). The focus in the leukemia studies has been on disease latency, time of peak incidence rates, clinical course, shape of the dose-response curve and changes in risk over time for various types of leukemia in relationship to shielded kerma and bone marrow radiation dose, age at time of exposure, and gender. The extreme understanding and cooperation of the Japanese atomic bomb survivors, control subjects, physicians of Hiroshima and Nagasaki, government authorities, and the citizens of both cities has resulted in an epidemiological study that is almost unparalleled in medical history. PMID- 9368296 TI - Brain damage among individuals exposed prenatally to ionizing radiation: a 1993 review. AB - Mental retardation as a result of prenatal exposure to ionizing radiation is not a common phenomenon when compared to the incidence of cancer, but it has nevertheless been well-documented. This article describes results from studies of individuals who were exposed prenatally to radiation in Hiroshima and Nagasaki. The critical time of exposure, when the most significant damage was done, was during the 8th-15th week of gestation, with a lesser effect at 16-25 weeks. Individuals in the study were assessed by measurement of an intelligence quotient and by examination of school performance. Studies show that the period of 8-15 weeks of gestation coincides with a key time for neuronal cell migration in the developing brain. There is continuing investigation of the mechanism of this migration and how it might be disrupted by ionizing radiation. PMID- 9368299 TI - Investigation of the impact of radiation dose on hormones, biologically active metabolites and immunoglobulins in Chernobyl accident recovery workers. AB - One hundred twenty-five Chernobyl accident recovery workers (liquidators) who were exposed to low-dose radiation were studied over a period of 4-6 years for changes in levels of hormones, arachidonic acid metabolites and cyclic nucleotides. Some significant changes were observed, especially in the levels of metabolites that are regulators of cell functions. In comparison to controls, there were increased levels of thyroxin, cortisol, thromboxane B2, and immunoglobulins G, A and M, and reduced levels of growth hormone, cyclic nucleotides and 6-keto-prostaglandin F1. The degree or presence of these metabolite imbalances did not correlate with the level of the radiation dose received. The only change found that did relate to the radiation dose received was a statistically significant increase in levels of biomarkers for oxidative stress, seen in workers who received higher doses. PMID- 9368298 TI - Morbidity in a large cohort study of children born to mothers exposed to radiation from Chernobyl. AB - Reproductive health was reviewed in four oblasts of the Republic of Belarus that were either heavily exposed (Mogilev and Gomel) or lightly exposed (Brest and Vitebsk) to ionizing radiation after the meltdown of a nuclear reactor in Chernobyl. A retrospective analysis was conducted on pregnancies occurring between January 1, 1982, and December 31, 1990, and a comparison of results was made between pregnancy outcomes prior to and after the meltdown for individuals residing in heavily exposed and lightly exposed oblasts. Pregnant women who resided in heavily exposed oblasts appeared to be at risk for development of toxemia, renal insufficiency and anemia. Neonates born in heavily contaminated areas were apparently at risk for development of anemia and congenital malformations and perinatal death. In addition, a cohort of 757 neonates, 0-18 months old, with a normal physical examination, was identified for laboratory analysis of hematological, immunological, endocrinological and nutritional status. Decreased levels of copper and zinc were documented in erythrocytes from neonates from heavily contaminated oblasts, findings that may be related more to inadequate nutrition than to radiation exposure. Increased absolute "null" lymphocyte number and diminished absolute T lymphocyte number with a reduction in the "helper" (i.e., T4) subclass of T cells were evident in neonates born-in heavily exposed oblasts. Geographic differences in reproductive health and immune status are apparent in Belarus that may be related to radiation exposure. Additional studies are required to exclude confounding variables and possible selection bias. PMID- 9368300 TI - Integrated retrospective radiation dose assessment. AB - Radiation dose reconstruction is used to estimate exposure to radiation that has occurred externally, e.g., from an atomic bomb, or internally, e.g., from radionuclide ingestion. This commentary reviews techniques for biological dosimetry that have been developed to estimate radiation doses from internal exposures, but which can also be used to estimate external exposures. The author argues for increased development and use of these biological tools. PMID- 9368301 TI - Analysis of chromosome aberrations in atomic bomb survivors for dose assessment: studies at the Radiation Effects Research Foundation from 1968 to 1993. AB - Exposure to ionizing radiation causes damage to living cells, especially to DNA in the cell nucleus. The degree of this cellular damage depends on the amount of radiation administered. This review discusses current findings concerning radiation-induced chromosome aberrations that were produced in 1945 and that can still be observed in the somatic cells of atomic bomb survivors in Hiroshima and Nagasaki. The scoring methods of G-banding and fluorescence in situ hybridization are compared. In addition, some findings concerning chromosomal aberrations in citizens of the former Soviet Union affected by the Chernobyl accident are presented. PMID- 9368302 TI - A 1993 report on reconstruction of environmental exposures and uncertainties in support of epidemiological studies related to low-dose radiation. AB - Studies have been progressing for about eight years on the reconstruction of historical doses from past releases of radioactive materials to the environment. This work has been performed at the University of Utah and the Pacific Northwest National Laboratory in Richland, WA. This review provides an update on advances in the area of environmental dosimetry and illustrations of how techniques are being applied in epidemiological studies related to low-dose radiation. Two points will be emphasized. The first is the message of how much progress there has been in environmental dosimetry over the past decade and how this dosimetry, when combined with epidemiology, can result in powerful tools to yield a better understanding of risk from exposure. The second point to be emphasized is that our work focuses on dosimetry only, although it is important for different disciplines to work together to determine outcomes. PMID- 9368303 TI - Emerging technological bases for retrospective dosimetry. AB - In this article we discuss examples of challenging problems in retrospective dosimetry and describe some promising solutions. The ability to make measurements by accelerator mass spectrometry and luminescence techniques promises to provide improved dosimetry for regions of Belarus, Ukraine and Russian Federation contaminated by radionuclides from the Chernobyl accident. In addition, it may soon be possible to resolve the large neutron discrepancy in the dosimetry system for Hiroshima through novel measurement techniques that can be used to reconstruct the fast-neutron fluence emitted by the bomb some 51 years ago. Important advances in molecular cytogenetics and electron paramagnetic resonance measurements have produced biodosimeters that show potential in retrospective dosimetry. The most promising of these are the frequency of reciprocal translocations measured in chromosomes of blood lymphocytes using fluorescence in situ hybridization and the electron paramagnetic resonance signal in tooth enamel. PMID- 9368304 TI - Chromosomal analysis to assess radiation dose. AB - This brief account of dosimetry based on cytogenetic assays reviews the sensitivity of the method and the speed with which a dose estimate can be obtained. The usefulness of chromosome studies to physicians is also discussed. Medical uses include confirming triage category for highly irradiated subjects and providing evidence for nonuniform exposure or other reasons for the presence of surviving functional stem cells. Such information can assist in medical management decisions, especially regarding transplantation of marrow or stem cells and treatment with growth factors. For subjects exposed to zero or low doses, cytogenetic studies can provide useful information for assisting physicians in counseling. PMID- 9368305 TI - An epidemiological overview of Chernobyl-related research. PMID- 9368306 TI - Overview of 1993 research activities in Belarus related to the Chernobyl accident. AB - This overview describes the medical and biological consequences of the Chernobyl nuclear power plant accident that had been assessed by Belarus scientists as of 1993. In particular, childhood thyroid cancer has increased in both frequency and severity. Other malignant tumors may have also increased, as may have childhood diseases that result from impaired immune function. It is unknown whether these increases in human disease (other than thyroid cancer) are due to improved methods of reporting or to exposure to ionizing radiation. In addition to the medical consequences of radiation damage, there are also significant psychological problems endured by the population living in contaminated areas. The Republic of Belarus has participated in several international programs for the study and management of widespread radiation exposure, and will continue to do so. Programs to address issues of radiation protection and population safety are being implemented wherever possible. PMID- 9368307 TI - Design and analysis of epidemiological studies of excess cancer among children exposed to Chernobyl radionuclides. AB - Within the last decade, a substantial amount of attention has been devoted to etiological research on the association between exposure to fallout radionuclides from the Chernobyl accident and radiation-induced late effects (cancer) among children. A majority of the studies completed to date have been of the descriptive type, which only correlate average population exposure with average rate of cancer incidence as a function of calendar period. Since individual dosimetry is not performed in descriptive studies, it is unclear whether exposure precedes the development of cancer and a final decision cannot be made regarding the association between radiation exposure and cancer. This paper reviews the background epidemiology and outlines an analytical study design that is needed to clarify the unclear association between Chernobyl fallout exposure and childhood cancer. We discuss the essential elements of an analytical case-control design such as genetic predisposition, vital statistics, sample size and power determinations, ascertainment of cases and controls, and phenomenological dose modeling to establish individual doses. Examples such as cytogenetic biodosimetry, medical radiation dosimetry, and cytogenetic characterization of leukemia to minimize exposure and diagnostic misclassification are provided. We recommend the analytical methods described in this paper for studying the role of Chernobyl radionuclides and development of childhood cancer. PMID- 9368308 TI - Epidemiology of childhood cancer in Belarus: review of data 1978-1994, and discussion of the new Belarusian Childhood Cancer Registry. AB - The Chernobyl accident in 1986 had a major ecological impact, with the bulk of the radioactive contamination affecting Belarus, the Ukraine and Russian Federation. Belarus has a nationwide general cancer registry that dates back to 1965, which allows a comparison of cancer incidence rates from before and after the accident. Preliminary analysis indicates that there has been an increased incidence of all cancers, with thyroid cancer accounting for most of that change. When cancer incidence data from Belarus are compared to data from the U.S., there is a higher incidence of thyroid cancer and a slightly higher incidence of Hodgkin's disease and non-Hodgkin's lymphoma in Belarus, but a lower reported incidence of leukemia and brain tumors. The Belarusian State Cancer Registry is being used as a foundation for the development of a more comprehensive childhood cancer registry. PMID- 9368309 TI - Approaches for studying radiation-induced leukemia. AB - According to the conclusion of the International Programme on the Health Effects of the Chernobyl Accident (IPHECA) Haematology Pilot Project (1991-1995), there was no increase in the incidence of malignant disease in hematopoietic and lymphoid tissues after the Chernobyl accident. Nevertheless, since studies of A bomb survivors indicate that the peak in morbidity may occur more than 10 years after radiation exposure, long-term studies of hemoblastoses and myelodysplastic syndromes are needed today. Study of these leukemias and lymphomas that are potentially induced by ionizing radiation must include both fundamental and applied approaches, i.e., A) epidemiological design; B) utilization of modern methods of diagnosis (cytomorphology, immunocytochemistry, cytogenetics); C) studies of gene mutations, mechanisms of apoptosis, and G1 delay; D) monitoring of oncogene and multidrug resistance gene expression, and E) tracking changes in cell-cell signaling in the bone marrow microenvironment. PMID- 9368310 TI - The epidemiological situation of thyroid cancer in Belarus. AB - Starting in 1990, an increasing number of children in regions adjacent to the site of the Chernobyl nuclear accident have been diagnosed as suffering from thyroid cancer. Using available data up to 1994, the geographical distribution, time and cohort trends, age distribution and other characteristics of this epidemic are reviewed. The results show that the geographical distribution is similar to that of iodine-131 after the nuclear accident. When looking at cohorts of children born in the same years, one can see that the incidence has been increasing steadily since 1990; deviations from this pattern might be explained by active case finding. A causal relationship with the Chernobyl accident appears the most likely interpretation of these results. Possible modifying factors should, however, be examined closely. PMID- 9368312 TI - Therapy of radiation injury. AB - It is apparent from preclinical and clinical research to date that continued evaluation of new and alternative treatment strategies is required to eliminate the obligate periods of neutropenia and thrombocytopenia after acute high-dose irradiation. Future treatment strategies may involve new combinations of cytokines to affect hematopoietic stem cell proliferation and "engineered" cellular grafts to provide short-term in vivo expansion of neutrophils and platelets in an effort to bridge the cytopenic gap until endogenous or transplanted stem cells regenerate the hematopoietic and immune systems. Cytokine mobilized peripheral blood and cord blood will provide alternative sources of allogeneic stem and progenitor cells in support of primary engraftment, delayed engraftment or secondary failure of the initial graft, as well as starting populations for various ex vivo expansion protocols. Further insights into the relative quality of stem cell populations and the factors that regulate their survival and self renewal, and the identification and roles of adhesion molecules in stem cell mobilization, engraftment, and interaction with the adult marrow microenvironment will provide the basis for future treatment strategies for the radiation-induced hematopoietic syndrome. As our ability to treat the hematopoietic syndrome improves, damage to other organ systems such as the skin, lung, and/or gastrointestinal tissue will emerge as dose-limiting. At the same time, the characterization of receptors for inflammatory cytokines, cytokine receptor antagonists, and anti-endotoxin antibodies has allowed significant insights into the mechanisms and pathogenesis of sepsis. However, translation of this knowledge into a treatment modality for septic patients is precluded by the lack of any clear-cut beneficial effect from the many clinical trials. The research and clinical results presented in this volume and recent conferences reflect the body of knowledge that will lead to further developments in assessment, prophylaxis, and treatment of radiation injuries in the areas of infectious disease and the hematopoietic, gastrointestinal, and cutaneous syndromes. PMID- 9368311 TI - Changes in registered congenital anomalies in the Republic of Belarus after the Chernobyl accident. AB - A descriptive analysis of birth defects and malformations was performed to assess whether the rates of these defects correlate with the geographic areas of Belarus that received different levels of 137Cs contamination resulting from the Chernobyl catastrophe. Since this accident in 1986, the frequency of both congenital and fetal abnormalities in the Republic of Belarus has apparently increased. This increase is most prominent in areas with at least 555 9Bq/m2 radioactive contamination, although it has not been possible to correlate the individual dose received by a pregnant woman with the incidence of congenital malformations. The types of anomalies that were most increased in frequency were multiple congenital malformations, polydactyly, and reduction limb defects. These malformations are commonly associated with dominant new mutations. Chromosomal disorders such as occur in Down syndrome were not increased in frequency, nor could teratogenic effects be attributed to exposure to ionizing radiation. Preventive measures have apparently reduced the number of births with congenital abnormalities but have had no apparent effect on the frequency of fetal defects. Results of our analysis are consistent with the hypothesis that ionizing radiation released during the Chernobyl accident may have placed fetuses and neonates at risk for congenital malformations. Epidemiological studies are now required to determine whether a mother's radiation dose correlates with congenital malformations in her children. PMID- 9368313 TI - Acute radiation disease and biological dosimetry in 1993. AB - Mankind is at risk for accidental exposure to ionizing radiation. The experience in evaluating and treating victims of radiation exposure is briefly reviewed based upon accidents occurring over the past 25 years. Individual cases of acute toxicities to the skin, gastrointestinal tract, liver and bone marrow are presented. Biodosimetry (utilizing chromosome analysis of peripheral blood lymphocytes and bone marrow and electron spin resonance spectrometry of dental enamel) has been utilized in radiation accidents to assess individual dose. Variability in the dose of ionizing radiation received is typical among the population affected by the Chernobyl accident. Whereas the acute radiation syndrome resulting in a high mortality has been well-documented, little information is available regarding the effects of chronic, low-level exposure from the Chernobyl accident. PMID- 9368315 TI - Criteria for the selection of radiation accident victims for stem cell transplantation. AB - The management of acute radiation syndrome in persons inadvertently exposed to total-body irradiation greatly benefits from the experience gained in previous clinical management situations. Within the framework of exposure to high doses, one of the most critical issues is the question of whether hematopoietic stem cell transplantation is indicated. A valid answer can be given with appropriate accuracy based on a thorough analysis and evaluation of all accessible case histories. Based on the clinical evaluation of patients severely affected with acute radiation syndrome, the following recommendations may be issued. There is limited indication for stem cell transplantation when there is accompanying severe radiation damage to organ systems other than the hematopoietic system. The optimum duration of pancytopenia can be estimated using the biomathematical model introduced in this article. PMID- 9368316 TI - The Chernobyl governmental program: two years of experience at the Belarusian Bone Marrow Transplant Centre. AB - The Bone Marrow Transplantation Program in Belarus was founded in 1992, and in 1993, a Bone Marrow Transplantation Centre was created in Minsk. From February 1994 to April 1996, 19 allogeneic bone marrow, 16 autologous bone marrow and 10 autologous peripheral blood stem cell transplantations were performed. Reasons for transplantation included chronic myeloid leukemia, multiple myeloma, severe aplastic anemia, acute myeloid leukemia, acute lymphoblastic leukemia, progressive myelofibrosis, Hodgkin's disease, non-Hodgkin's lymphoma, and neuroblastoma. Among the patients were two liquidators involved in the Chernobyl cleanup activity, both of whom underwent allogeneic bone marrow transplantation. A variety of ablative preparative regimens were used, and blood progenitor cells were mobilized by treatment with Cytoxan and granulocyte colony-stimulating factor. Therapy-related deaths resulted from graft-versus-host disease, septic shock, veno-occlusive disease bleeding and intestinal pulmonary fibrosis. Because the transplantation procedures were carried out on people who continued to be exposed to low-level irradiation, the post-transplantation period included a conservative strategy for prevention of graft-versus-host disease. There was nothing unusual about the post-transplantation period, although uncertainty about the continuing radiation dose should be taken into account when interpreting these data. PMID- 9368314 TI - Early identification of radiation accident victims for therapy of bone marrow failure. AB - Ionizing radiation damages the lymphohematopoietic system via direct effects on viability and/or function of hematopoietic stem/progenitor cells and via abnormal production of cytokines (i.e., growth factors). Other tissues that have a rapid turnover (including the gastrointestinal tract and skin) are also profoundly affected by acute radiation exposure. A major issue in selection of appropriate therapy for bone marrow failure (i.e., the bone marrow syndrome) is early assessment of radiation dose. Although several biological markers are available for assessing dose received, the absolute polymorphonuclear neutrophil (PMN) and/or lymphocyte counts, together with clinical presentation (i.e., time to onset of nausea and vomiting, etc.) still provide the most practical and timely assessment of radiation dose. Limited information is available regarding CD34 positive cell frequency as a measure of radiation-induced damage to the bone marrow. Since a subpopulation of radioresistant hematopoietic stem cells may persist after exposure to high-dose radiation, the primary goal of therapy is to provide an adequate number of lymphohematopoietic stem cells for a finite (rather than indefinite) period, after which endogenous stem cells may reinstate lymphohematopoiesis. A model is presented which describes the hypothesis that stem cell clonal repopulation over time is distinct in transplant recipients who have received moderate compared to high-dose radiation exposures. Since some individuals receiving high levels of radiation and presenting with rapidly declining PMN counts spontaneously recover lymphohematopoiesis, better tools (including CD34-positive cell analysis) must be developed to select the appropriate therapy for exposed individuals. PMID- 9368317 TI - Potential use of hematopoietic stem cells after radiation injury. AB - Bone marrow transplantation has been used for several years in the treatment of hematopoietic system malfunction. However, this particular therapy option has had minimal benefit when the hematopoietic system failure results from radiation exposure, such as that after the Chernobyl accident. In the last ten years, there has been considerable progress in the development of methods to encourage stem cell repopulation with the application of hematopoietic growth factors, and to reconstitute the hematopoietic system with stem cells extracted from the peripheral blood. Problems with allogeneic bone marrow or peripheral blood stem cell transplantation as a therapy option include graft-versus-host disease and a shortage of human leukocyte antigen (HLA)-matched donors. These problems can be overcome if an autologous bone marrow or peripheral blood transplant is performed, but this is not always practical. Another approach to combat these difficulties is the use of umbilical cord blood as a source of donor cells, since placental blood is rich in stem cells and less prone to lead to graft-versus-host disease than mature blood. PMID- 9368318 TI - Hematopoietic stem cells: inferences from in vivo assays. AB - Mice and humans both contain a population in their marrow which can permanently regenerate all of the hematopoietic lineages. This developmental potential was first demonstrated in myeloablated mice transplanted with genetically marked marrow obtained from congenic donors. More recently, this approach has been used to devise an in vivo limiting dilution assay for "competitive (lymphomyeloid) repopulating units" (CRU) that allows murine hematopoietic stem cells to be quantitated. Measurements of murine CRU have shown that this population expands concomitantly with the total hematopoietic system during ontogeny and to some extent post-transplant. During these periods of expansion, defective c-kit function can be seen to preferentially compromise CRU self-renewal more than early CRU detection (which requires differentiation and amplification of the progeny of CRU, but may not require extensive CRU self-renewal). In humans, a similar cell type with transplantable lymphomyeloid differentiation potential can be identified in cord blood on the basis of its ability to engraft sublethally irradiated immunodeficient nonobese diabetic/severe combined immunodeficient mice. Quantitation of these human CRU by limiting dilution analysis of unseparated, highly purified (CD34+CD38-) and cultured (CD34+CD38-) human cord blood cells indicates that their numbers (like the long-term culture-initiating cell [LTC-IC] population) can be slightly expanded in cytokine-supplemented serum free media, although not as extensively as anticipated from analogous studies of human marrow LTC-IC cultured under the same conditions. Taken together, the results of our studies suggest that the self-renewal of mitotically activated hematopoietic stem cells can be enhanced by their interactions with particular cytokine combinations whose effectiveness in this regard may change during ontogeny. PMID- 9368319 TI - In vitro expansion of hematopoietic stem cells. AB - We have investigated the effects of interleukin 3 (IL-3) and IL-1 on in vitro expansion of murine hematopoietic progenitors and stem cells using a highly purified progenitor population. Lineage negative, Ly-6A/E+, c-kit+ bone marrow cells from male mice were cultured in suspension in the presence of stem cell factor, IL-6, IL-11 and erythropoietin with or without IL-3 or IL-1. An exponential increase in total nucleated cell counts and about a 10-fold enhancement of nucleated cells by IL-3 were observed during the initial 10 days. Addition of IL-3 hastened the development but significantly suppressed the peak production of colony-forming cells. Addition of IL-1 also significantly suppressed the numbers of progenitors. We then tested the reconstituting ability of the cultured cells by transplanting cells together with "compromised" marrow cells into lethally irradiated mice. The cells expanded from enriched cells in the absence of IL-3 or IL-1 revealed engraftment at two, six and 10 months, while addition of IL-3 or IL-1 to the cultures significantly reduced the reconstituting ability. IL-3 and IL-1 may have negative modulatory effects on the self-renewal of stem cells. PMID- 9368320 TI - Resistance of human hematopoietic stem cells to a monoclonal antibody recognizing CD43. AB - Hematopoietic progenitor cells (HPC) interact with bone marrow stroma by adhesion molecules which are thought to be critically important to the regulation of hematopoiesis. The specific roles of individual adhesion molecules involved in these interactions remain poorly understood. A monoclonal antibody (mAb) recognizing CD43, an adhesion molecule highly expressed by HPC, induces apoptosis in CD34hiLin- marrow cells. This process operates at a single-cell level, and the initiation of apoptosis requires crosslinking of surface CD43 and the presence of cytokines. In contrast to HPC, more differentiated hematopoietic cells do not undergo apoptosis in response to the CD43-mediated stimulation. Not all progenitor cells undergo apoptosis upon stimulation of CD43. Dividing progenitor cells are most affected, whereas more primitive, quiescent cells survive anti CD43 mAb treatment. These surviving cells: A) are enriched for cobblestone area forming cells; B) repopulate fragments of human fetal bone implanted into CX.B-17 severe combined immunodeficiency (SCID/hu) mice; C) have a potential to differentiate in vivo to myeloid and lymphoid cells, and D) have a high proliferative potential in long-term stromal cell-free liquid culture. These data indicate tha cells with hematopoietic stem cell characteristics are relatively resistant to CD43-mediated apoptosis compared to HPC and that CD43 may function as a negative regulator of early events occurring during hematopoiesis. PMID- 9368321 TI - Transduction efficiency of cell lines and hematopoietic stem cells correlates with retrovirus receptor mRNA levels. AB - The low transduction efficiency of hematopoietic stem cells (HSC) using amphotropic retroviruses continues to plague gene therapy protocols. This low transduction efficiency may be related to a low level of amphotropic retrovirus binding to target cell receptors. We have assayed murine and human cell lines as well as primary bone marrow HSC populations for mRNA encoding retrovirus receptors. Total cellular RNA was amplified by reverse transcriptase-polymerase chain reaction and the level of ecotropic and amphotropic receptor mRNA was compared to the level of beta 2-microglobulin mRNA in the same cell populations. Cell lines that are easily transduced by ecotropic and amphotropic retroviruses have high levels of receptor mRNA. In studies using murine HSC-enriched populations obtained from bone marrow, we observed a high correlation between transduction efficiency and the level of ecotropic and amphotropic receptor mRNA. We predict from these findings that purification of monkey and human HSC populations with high levels of amphotropic receptor mRNA will enable us to obtain improved efficiency of gene transfer. PMID- 9368322 TI - Patterns of organ-specific engraftment by stem cell subsets and committed progenitors. AB - The kinetics of blood and organ engraftment following transplants of defined populations of hematopoietic stem/progenitor cells were investigated utilizing cell populations defined by surface antigen and rhodamine-123 staining. While long-term repopulating stem cells, short-term multipotent progenitors and committed progenitors all reconstituted peripheral blood red cells and splenic cellularity, only the population of cells that includes highly enriched long-term repopulating stem cells (Thy-1.1lowLinnegSca-1+Rh123low) reconstituted marrow cellularity. In addition, peripheral blood platelet and nucleated cell count increased only after transplant of the long-term repopulating population. These results argue that the major cell population that functions to reconstitute hematopoiesis after bone marrow transplantation is a primitive, marrow-homing stem cell. Transplantation of highly enriched multipotent progenitors that lack long-term reconstituting potential had no impact on hematopoietic recovery, apart from a transient increase in circulating erythrocytes. These results suggest that the primary cell population that functions to reconstitute hematopoiesis in a transplant setting is the long-term repopulating stem cell. This observation is discussed in the context of the normal hematopoietic process. PMID- 9368323 TI - Phenotypic and functional characterization of the hematopoietic stem cell. AB - The purpose of this report is to demonstrate the phenotypic and functional characteristics of a primitive hematopoietic stem cell (HSC). We present evidence that an isolated murine HSC can repopulate the hematopoietic tissues of lethally irradiated recipient animals long term. By limiting dilution, as few as ten isolated stem cells can reconstitute mice for their lifetime. The stem cell which we have isolated does not copurify with colony forming unit-spleen or radioprotect recipients from lethal radiation. The phenotypic characterization of this rare cell, which represents 0.005% of total bone marrow, includes either the absence or very low expression of markers associated with long-term repopulating cells described by other groups. We believe this stem cell represents a very early self-renewing stem cell in the mouse. PMID- 9368324 TI - Differential short-term and long-term repopulating ability of stem cell subsets in mice. AB - Hematopoietic reconsitution after transplantation requires the presence of cells with early and late repopulating ability. To determine the contribution of relatively immature and mature hematopoietic progenitor cells in engraftment, we used a modified rhodamine staining procedure to purify populations of rhodamine 123 (Rho)bright, Rhodull and Rho- cells from mouse steady-state bone marrow. Following transplantation of these subsets of stem cells in lethally irradiated mice, marrow repopulating cells were mainly present in the small fraction of Rho- cells, indicating that hematopoietic stem cells have a relatively high expression of P-glycoprotein. Similar cell populations could be purified from cytokine mobilized blood following treatment with cyclophosphamide and G-CSF. The Rho- cell population contained the majority of hematopoietic stem cells with in vivo marrow repopulating ability. In methylcellulose colony assays, the majority of the committed progenitor cells were present in Rhodull and Rhobright fractions. These results indicate that relatively primitive populations of hematopoietic stem cells that lack colony-forming capacity in vitro mediate the early phase of engraftment following syngeneic stem cell transplantation. PMID- 9368325 TI - Cord blood stem cell banking and transplantation. AB - Cord blood banking for the purpose of stem cell transplantation is a rapidly growing area of medical interest. Based on the fact that cord blood contains large numbers of stem and progenitor cells, transplantation of cord blood for marrow reconstitution was first attempted in 1988. The success of this initial transplant between related donor and patient rapidly led to the establishment of efforts to collect, store and eventually transplant unrelated cord blood samples. A collection and storage program established by the New York Blood Center has led to more than 400 such transplants. The results demonstrate acceptable rates of engraftment and little graft-versus-host disease compared to the results employing adult marrow. As a consequence of these observations, considerable effort is being made to establish cord blood banks around the world. PMID- 9368326 TI - Microenvironmental regulation of hematopoietic stem cells. AB - A major challenge in hematopoietic biology is the description and understanding of the molecular mechanisms responsible for the regulation of the primitive stem cell compartment. In one sense there exists a wealth of functional and physical properties which provide insight into the biology of the stem cell and its clonal progeny. However, much of this information is descriptive and available only as a function of complex in vivo assays. In order to move beyond these limitations, in vitro systems which accurately recapitulate the self-renewal, differentiation and proliferative behaviors of stem cells are required. We have approached this issue by focusing on the in vivo stem cell microenvironment. Dissection of this microenvironment into discrete cellular entities has yielded a cell line with in vitro stem cell supportive properties consistent with those which might be expected in a stem cell niche. Studies are summarized which suggest that a single stromal cell line provides a milieu which facilitates the in vitro maintenance of transplantable stem cells as well as the generation of large populations of committed progenitors. It is anticipated that this system will allow a direct analysis of stem cell regulatory pathways. PMID- 9368327 TI - Biology and mechanisms of action of synergistically stimulated myeloid progenitor cell proliferation and suppression by chemokines. AB - A number of cytokines can act together to stimulate/enhance the proliferation of hematopoietic stem and progenitor cells in a greater than additive fashion. An example of this is the combination of a colony-stimulating factor with a potent costimulating molecule such as steel factor. Certain members of the chemokine family of cytokines can suppress this synergistically enhanced proliferation. This review focuses on cytokines involved in these stimulating/enhancing/suppressing effects with regard to biological activity and what is beginning to be learned about the intracellular signal transduction events that may be mediating these effects. Examples of intracellular mediators involved include, but are not limited to, the Raf-1/ MAP kinase pathway and cyclin-dependent kinase inhibitors p21cip-1 and p27kip-1 for cell proliferation, and eukaryotic initiation factor-4E and 4E binding protein 1 for protein synthesis. PMID- 9368329 TI - Thrombopoietin: more than a lineage-specific megakaryocyte growth factor. AB - In the past two years thrombopoietin (TPO) has been cloned, its effects on cells of the megakaryocytic lineage have been described in detail and its use in clinical settings of myelosuppressive therapy has begun. Moreover, the mechanisms by which the hormone binds to its receptor have been studied in detail, and the intracellular pathways employed during TPO signaling have been extensively explored. Although most workers in the field predicted that TPO would be lineage specific, with physiologic effects limited to megakaryocytes and platelets, several features of Mpl biology suggest its influence on hematopoiesis may be more widespread than initially anticipated. To test this possibility, we and others have begun to explore whether TPO affects development of the hematopoietic stem cell. In suspension culture, TPO alone can support the survival of a fraction of hematopoietic stem cells but does not lead to their proliferation. However, in combination with interleukin 3 or stem cell factor, TPO accelerates hematopoietic stem cell entry into the cell cycle over that seen with these early acting cytokines alone, increases the number of subsequent cell divisions per unit time and results in the output of far greater numbers of colony-forming cells of all lineages. Conclusions from these in vitro studies are supported by two types of in vivo experiments. The administration of TPO to either normal or myelosuppressed animals causes an expansion of colony-forming unit (CFU) megakaryocyte, CFU-granulocyte-macrophage, CFU granulocyte/erythroid/macrophage/megakaryocyte and BFU-E, and elimination of TPO or its receptor by genetic engineering results in a substantial decrease in the numbers of these progenitors in both the marrow and spleen. It is thus becoming clear that the effects of TPO extend beyond that of a megakaryocyte-specific factor and suggest that the hematopoietic effects of administration of the hormone may be greater than initially anticipated. PMID- 9368328 TI - Transplantation of hematopoietic stem cells in utero. AB - Hematopoietic stem cell (HSC) transplantation in children and adults with congenital lymphohematopoietic disorders is limited by donor availability, graft failure, graft-versus-host disease (GVHD) and delayed immunological reconstitution. These problems may be circumvented by transplanting the patient before birth. Prenatal cellular therapy for the treatment of congenital diseases has tremendous theoretical appeal. Potential advantages of prenatal transplantation include: A) fetal immunologic immaturity and the potential for induction of donor-specific tolerance; B) available space in the developing bone marrow for engraftment of donor cells; C) the sterile, protective, fetal environment which provides isolation from environmental pathogens, and D) prevention of clinical manifestations of the disease. Normal hematopoietic and immunologic development during ontogeny creates a "window of opportunity" during which events favor the engraftment of transplanted allogeneic (and xenogeneic) HSC and their proliferation. This is a period in which the fetus is immunologically naive and thus incapable of rejecting the foreign HSC, and the expanding bone marrow spaces allow homing and engraftment of HSC without the need for myeloablation. Experiments in sheep have established the optimal age of the recipient, route of donor cell administration, sources of HSC, and other parameters necessary for the successful engraftment and long-term expression of donor HSC. In preclinical studies, transplantation of CD34-enriched or highly purified populations of human adult bone marrow cells in utero resulted in the long-term engraftment and expression of donor HSC without graft failure and GVHD. The strategies developed in allogeneic and xenogeneic fetal sheep models were used to successfully treat human fetuses with X-linked recessive severe combined immunodeficiency. PMID- 9368330 TI - Jaks and Stats in cytokine signaling. AB - Hematopoiesis is regulated through the binding of cytokines to receptors of the cytokine receptor superfamily. Although lacking catalytic domains, members of the cytokine receptor superfamily mediate ligand-dependent activation of protein tyrosine phosphorylation through their association and activation of members of the Janus kinase (Jak) family of protein tyrosine kinases. The activated Jaks phosphorylate the receptors which creates docking sites for SH2-containing signaling proteins which are tyrosine phosphorylated following their association with the complex. Among the substrates of tyrosine phosphorylation are members of the signal transducers and activators of the transcription family of proteins (Stats). Various cytokines induce the tyrosine phosphorylation and activation of one or more of the seven family members. The pattern of Stat activation provides a level of cytokine individuality that is not observed in the activation of other signaling pathways. The role of various Stats in the biological responses to cytokines has been assessed through the analysis of receptor mutations which disrupt Stat activation and more recently by disruption of the genes in mice. Our results have demonstrated that the activation of Stat5a and Stat5b by erythropoietin is critical for the activation of a number of immediate early genes but is not required for a mitogenic response. Mice in which the genes for Stat4 and Stat6 are disrupted are viable but lack functions that are mediated by interleukin 12 (IL-12) or IL-4, respectively, suggesting that these Stats perform very specific functions in immune responses. PMID- 9368331 TI - Frequency of point mutations in the gene for the G-CSF receptor in patients with chronic neutropenia undergoing G-CSF therapy. AB - Point mutations in the gene for the G-CSF receptor have been reported previously in a subgroup of patients with severe congenital neutropenia. Here, we investigated the frequency of these specific G-CSF receptor mutations in patients with neutropenic disorders undergoing treatment with recombinant human (r-metHu)G CSF (Filgrastim). Nucleotides 2306 to 2561, including the critical region (nucleotides 2384-2429) from the intracellular domain of the G-CSF receptor gene, were amplified by reverse transcriptase-polymerase chain reaction, and DNA was sequenced directly and after transformation in E. coli. Four of 30 patients with severe congenital neutropenia displayed a point mutation in the tested cytoplasmic region of the G-CSF receptor gene. Two of the four patients with a mutated G-CSF receptor developed acute myeloid leukemia secondary to congenital neutropenia. G-CSF receptor analyses were performed in myeloid cells taken at different time points in the four patients with the mutated receptor, and no correlation between occurrence of the mutation and time or dose of r-metHuG-CSF treatment was found. No point mutations in the G-CSF receptor critical domain could be detected in cells from the other 26 congenital neutropenia patients. Additionally, no G-CSF receptor point mutations could be seen in neutrophils, blood and bone marrow mononuclear cells from patients with cyclic or idiopathic neutropenia, and bone marrow mononuclear cells from patients suffering from severe aplastic anemia. Similar results were obtained by Touw et al., demonstrating that five out of 25 patients with congenital neutropenia reveal G CSF receptor mutations. These data show that the point mutations in the critical region of the intracellular part of the G-CSF receptor occur only in a subgroup of severe congenital neutropenia patients. Furthermore, our data suggest that the described G-CSF receptor point mutations are not correlated with the start, duration or doses of r-metHuG-CSF treatment, but might result from genetic instability in the G-CSF receptor gene in severe congenital neutropenia. PMID- 9368332 TI - Gene transfer into hematopoietic cells. AB - Transfer of a gene into stem cells with subsequent lineage-specific gene expression is a desired goal with many potential therapeutic applications. Retroviral vectors developed from murine leukemia viruses reproducibly transfer genes into murine stem cells, but are inefficient at gene insertion into stem cells of larger animals or man. A growing knowledge of stem cell biology suggests that this inefficiency reflects the quiescent state of stem cells, even when incubated in the presence of multiple cytokines and low expression of the receptor for amphotropic retroviral vectors. Alternative vector systems are being explored in an effort to overcome these barriers to stem cell-targeted gene transfer. Our work has shown that recombinant adeno-associated virus vectors, which have the potential for transducing quiescent cells, transfer, express and integrate a globin gene linked to its normal regulatory elements in human erythroid cells, but only at very high multiplicities of infection. The integrated genome was stable and the encoded globin gene was expressed at levels equivalent to a normal globin gene. PMID- 9368333 TI - Transduction of hematopoietic stem cells in humans and in nonhuman primates. AB - Primitive hematopoietic progenitor and stem cells have been pursued as highly desirable targets for genetic therapy. Retroviral vectors have been used for the majority of preclinical and clinical studies directed at these cells; however, both preclinical and early clinical studies indicate that the gene transfer efficiency of the current generation of vectors using known transduction conditions into primate and human repopulating stem cells is too low to be of clinical utility in most situations. In this presentation I will summarize the status of our completed and ongoing clinical genetic marking trials, and describe our efforts in the laboratory and use of primate transplantation models to improve on these results. PMID- 9368334 TI - Regulation of gene expression by human foamy virus and potentials of foamy viral vectors. AB - The hallmarks of the spumaretrovirus or human foamy virus (HFV) are summarized and discussed with special focus on the potentials to use HFV as a new retroviral vector system. The special features of HFV are the expression of pol by splicing and start of translation at a defined initiation codon. The first Met of Pol is conserved in the six known foamy virus genomic sequences. Another remarkable characteristic of HFV is the presence of a Gly-Arg-rich sequence instead of the Cys-Cys motif of the classical retroviral nuclecapsid proteins. The preferential budding of HFV into cytoplasmic vesicles and the potential to exploit it in the application of corresponding vector systems is discussed. In addition, recent reports of transducing marker genes into susceptible cells will be reviewed. PMID- 9368335 TI - Hematopoietic transplantation: state of the art. AB - Bone marrow transplantation has developed from an experimental therapy for a small group of patients to a well-established form of treatment with well-defined indications for a large group of patients with hematological and non hematological neoplasia. The availability of suitable donors has more than doubled due to large registries of persons volunteering for marrow donation. With improved techniques for histocompatibility typing, it has become possible to study the role of specific histoincompatibilities for graft-versus-host disease and graft-versus-leukemia reactions. The source of hematopoietic stem cells now comprises not only bone marrow, but also stem cells mobilized into the peripheral blood and stem cells from cord blood. Hematopoietic growth factors have found a large distribution in the mobilization of stem cells and support for hematological reconstitution. They are studied for the expansion of pools of stem cells. Reconstitution of antileukemia and antiviral activity has been achieved by adoptive immunotherapy using lymphocytes and dendritic cells cultured in vitro. The way from transplantation of bone marrow to cellular and genetic engineering leads to new indications such as treatment of severe autoimmune disease. Hematopoietic transplantation has come a long way and it still has possible new areas of application. PMID- 9368336 TI - Purging of peripheral blood progenitor cell autografts and treatment of minimal residual disease. AB - Clinical success of autologous peripheral blood progenitor cell (PBPC) transplantation is challenged by relapse of malignant disease which might at least in part be mediated by graft-contaminating tumor cells. Although the clinical efficacy of tumor cell depletion still remains to be demonstrated, multiple purging strategies are currently pursued in the context of autologous stem cell transplantation. This report discusses ex vivo manipulations of PBPC transplants with respect to purging of tumor cells, including positive selection of CD34+ cells with or without negative depletion of tumor cells as well as ex vivo expansion techniques. Moreover, strategies with an adoptive immunotherapy using ex vivo-generated autologous dendritic cells for the treatment of minimal residual disease after stem cell transplantation will be discussed here. PMID- 9368337 TI - Engraftment of hematopoietic stem cells in nonmyeloablated and myeloablated hosts. AB - Hematopoietic stem cell engraftment has traditionally been assessed in irradiated murine hosts. More recently, we and others have shown that engraftment is virtually quantitative in host animals who have received no preconditioning myeloablation. It appears that at the stem cell level, engraftment may even be favored in the normal host. The final phenotypic readout in the engrafted animal is then determined by competition between the engrafted stem cells and the number of residual host stem cells. Further studies have indicated that with cytokine exposure in vitro, in vivo or 5-fluorouracil exposure and consequent stimulation of primitive hematopoietic stem cells to enter cell cycle, an engraftment defect relating to long-term engraftment occurs. This occurs in the face of an expansion of cycling surrogate stem cells as mirrored by the high proliferative potential colony-forming cell. These data indicate that the phenotype of the hematopoietic stem cell, as assessed in vitro, may not give insight into the phenotype of these cells in vivo. PMID- 9368338 TI - Bone marrow transplantation for therapy in autoimmune disease. AB - A variety of clinical and experimental reports have shown the interdependence between bone marrow and autoimmune diseases. Autoimmune diseases can be transferred as well as cured by bone marrow transplantation (BMT). The widespread application of this therapeutic approach is limited today by the morbidity and mortality associated with BMT, including failure of engraftment, graft-versus host disease (GVHD) and the toxicity from lethal conditioning approaches. Mixed chimerism (with the advantage of superior immunocompetence of the host and a relative protection against GVHD) can be achieved with incomplete ablation conditioning regimens. BMT may provide a potential strategy to treat those autoimmune diseases for which today only symptomatic treatment is available. PMID- 9368339 TI - Peripheral blood progenitor cell transplantation as an alternative to autologous marrow transplantation in the treatment of acute myeloid leukemia. AB - Herein we report on the feasibility of mobilizing peripheral blood progenitor cells (PBPC) in a prospective study of the HOVON-SAKK Groups in 96 cases with newly diagnosed acute myeloid leukemia (AML). Among 96 patients, 76 patients (79%) entered complete remission. Mobilization was undertaken with variable dosages of G-CSF in 63 patients, and 54 patients (87%) were leukapheresed. The comparative yields of pheresis following the G-CSF schedules and hematopoietic recovery data are presented and discussed. PBPC transplantation results in faster hematopoietic regeneration compared to autologous marrow grafting in the prior AML HOVON study. PMID- 9368340 TI - Assay systems for hematopoietic stem and progenitor cells. AB - Progress in our understanding of the hematopoietic system as well as novel cellular and molecular biology techniques are increasingly promoting the ex vivo manipulation and therapeutic use of hematopoietic stem and progenitor cells. For both, development of stem cell therapies and basic hematopoietic research, test systems for hematopoietic stem cells are required to monitor the intrinsic and ex vivo-induced properties of these cells. In vitro assays for primitive hematopoietic cells (colony-forming units-blast, cobblestone area-forming cells, long-term culture-initiating cells [LTC-IC]) have been established which demonstrate the proliferative and differentiation capacities of these populations. The potentials of these assays have been recently enhanced by the extended LTC and the switch LTC modifications. Although some hematopoietic cells characterized in vitro have the multipotential and proliferative properties of pluripotent hematopoietic stem cells (PHSC), their capacity to long-term repopulate hematopoiesis in vivo, a hallmark of PHSC, has not been established. Without this confirmation, populations defined in vitro should not be considered the equivalent of PHSC. In animals, the properties of primitive hematopoietic cells can be systematically analyzed by multiple in vivo assays. Therefore, various strategies have been pursued to develop an animal model for human hematopoiesis. In fetal sheep and immunodeficient mice, the functions of human PHSC are reproduced, and long-term multilineage repopulation capacity and extensive proliferative potential have been demonstrated for xenografted human cells. Thus, both models can be considered stem cell assays and may significantly enhance the study of early hematopoiesis and the development of therapeutic strategies. PMID- 9368341 TI - Blast cell colony assays and LTC-IC assay (discussion). PMID- 9368342 TI - Assay of human stem cells by repopulation of NOD/SCID mice. AB - The only conclusive method to assay stem cells is to follow their ability to repopulate conditioned recipients, making it difficult to study human stem cells. The development of systems to transplant human hematopoietic cells into immune deficient mice lays the foundation for such an experimental repopulation assay for primitive human cells. Cell purification and gene marking studies have shown that the repopulating cells, termed severe-combined immunodeficiency (SCID) mouse repopulating cells (SRC), are primitive and distinct from most of the progenitors that are detected using short and long-term in vitro culture assays. The SRC are exclusively CD34+CD38- and poorly infected with retrovirus vectors. These gene marking data are reminiscent of the human clinical trials establishing that the SRC assay is a good surrogate to develop improved transduction methods. Limiting dilution analysis has been used to establish a quantitative assay for SRC that can be used to precisely determine the effect of various cytokine cocktails on the proliferation and differentiation of SRC during in vitro culture. PMID- 9368343 TI - The human/sheep xenograft model for assay of human HSC (discussion). PMID- 9368344 TI - What characterizes the earliest stem cell? What is true for human stem cells? (discussion). PMID- 9368345 TI - Stem cell heterogeneity (discussion). PMID- 9368346 TI - Intrinsic control of stem cell fate. AB - Efforts to expand the number of stem cells ex vivo are based on the assumption that the self-renewal properties of stem cells are subject to extrinsic control. Although loss of stem cell properties ex vivo has been well-documented, conclusive evidence for a gain of stem cell function in vitro has not been forthcoming. In this short discussion paper, some issues related to the self renewal of stem cells in relation to future experimental strategies are presented. PMID- 9368348 TI - Stem cell proliferation: ex vivo and in vivo observations. AB - The contribution of stem cells to the early phases of hematopoietic engraftment is controversial, as is the issue of the number of stem cells required for successful long-term engraftment in man. An extensive body of data exists in the murine system and the degree to which this can be extrapolated to man is discussed. Other variables involving stem cells include their efficiency of homing to the bone marrow, their previous proliferative history influencing telomere length and their ability to upregulate telomerase. The extent to which stem cell numbers increase in vivo upon transplantation, or ex vivo upon cytokine stimulation, is discussed and the question as to the ability of nonstochastic extrinsic influences to alter stem cell self-renewal probability is raised. PMID- 9368347 TI - Extrinsic control of stem cell fate: practical considerations. AB - Decades of experimental data suggest that hematopoietic stem cells can remain quiescent, divide, differentiate or die and further, that these cell fate decisions are determined by extracellular signals provided by the hematopoietic microenvironment (ME). Given the importance of the ME for regulating hematopoiesis, it is imperative that transplanted stem cells migrate efficiently and home to appropriate niches where they can receive regulatory signals. Currently the rapid engraftment seen after transplantation of cytokine-mobilized blood-derived stem cells would suggest that these cells are well-equipped for homing. More recent concerns have now been raised by the possibility that in vitro expansion of these stem cells may diminish their ability to engraft. One possible explanation for this is that expansion protocols may alter adhesion molecule expression and consequently homing. Data presented in this report indicate that expression of adhesion molecules is altered following in vitro exposure to recombinant cytokines, and that various combinations of cytokines differentially modulate adhesion molecule expression. PMID- 9368349 TI - What are the current limitations for HSC transduction? How can we overcome them? (discussion). PMID- 9368350 TI - Stem cell gene therapy, position effects and chromatin insulators. AB - Low efficiency of gene transfer is the main obstacle for a clinically effective gene therapy at the level of the pluripotent hematopoietic stem cell. Another important aspect of stem cell gene therapy, the actual expression of the transduced genes, has only been investigated adequately in very few studies, mainly for globin genes. Transcriptional silencing and position effects due to negative effects of surrounding chromatin on the expression of randomly integrated vector sequences may seriously jeopardize the success of current gene therapy strategies, even if transduction efficiency can be significantly improved. We propose the incorporation of chromatin insulators in the design of gene therapy vectors to overcome the problem of position effects. Chromatin insulators are protein-binding DNA elements that lack intrinsic promoter/enhancer activity but shelter genes from transcriptional influence of surrounding chromatin. The best characterized insulators are from Drosophila. We hypothesize that the important cellular function of chromatin organization is evolutionarily conserved and that human homologs to Drosophila insulator binding proteins such as the suppressor of Hairy-wing exist and can be cloned. Using these putative proteins, it should be possible to identify corresponding minimal binding sites with insulator activity. The design and incorporation of effective chromatin insulator sequences in the next generation of gene therapy vectors should lead to improved and more predictable expression of therapeutic transgenes and constitute an important step toward clinically effective gene therapy. PMID- 9368351 TI - Good manufacturing practice production of human stem cells for somatic cell and gene therapy. AB - Peripheral blood stem cells (PBSC) are used for transplantation to reconstitute the hematopoietic system after high-dose chemotherapy. PBSC are harvested from peripheral blood upon successful mobilization by cytokines and/or chemotherapy. Further in vitro manipulation steps like enrichment of CD34+ PBSC or gene transfer can be performed. To ensure the quality and safety of the final cell preparations intended for transplantation, national and international guidelines and regulations have been issued. Herein the implementation of a quality assurance program including the principles of good manufacturing practice (GMP) and a quality control (QC) system is one major concern. GMP regulations apply to all phases of cell collection, processing and storage as well as documentation, training of personnel, and the laboratory facility. QC measures have to be taken to ensure consistent quality and safety with an emphasis on preventing any deficiencies. PMID- 9368352 TI - A practice model for enhancing effective coping in child welfare families. AB - Some degree of stress is of necessity associated with child welfare interventions. This stress adds to that already present in service consumers' situations. This article offers help to child welfare students and beginning practitioners in understanding and reducing the kinds of stress involved in child welfare interventions. PMID- 9368353 TI - A family of gram-negative bacterial outer membrane factors that function in the export of proteins, carbohydrates, drugs and heavy metals from gram-negative bacteria. AB - Gram-negative bacteria have evolved transport complexes that export macromolecules and toxic substances across the two membranes of the cell envelope in a single energy coupled step. The process requires (1) a cytoplasmic membrane export system, (2) a membrane fusion protein (MFP), and (3) an outer membrane factor (OMF). Families comprising the former two constituents have been described previously. We here present an analysis of the phylogenetic and structural characteristics of the OMF family. Twenty-one members of this family have been identified, and based on available evidence, they function in conjunction with ABC, RND, MFS and/or other types of cytoplasmic transport systems. OMFs exhibit fairly uniform sizes (398-495 residues with two exceptions), and based on computational analyses, they may form beta-barrel structures consisting of up to 16 beta-strands. Phylogenetic analyses reveal that while the MFPs cluster in accordance with the type of cytoplasmic membrane transport systems with which they function, OMFs do not. We conclude that OMFs probably comprise a family of outer membrane porin-type proteins of uniform structure which did not coevolve with their cognate cytoplasmic membrane transport systems. PMID- 9368354 TI - Blue and yellow laccases of ligninolytic fungi. AB - Extracellular laccases from submerged cultures of Coriolus versicolor BKM F-116, Panus tigrinus 8/18, Phlebia radiata 79 (ATCC 64658), Phlebia tremellosa 77-51 and from cultures of Pa. tigrinus 8/18, Ph. radiata 79 and Agaricus bisporus D 649 grown on wheat straw (solid-state fermentation) were purified. All enzymes from submerged cultures had a blue colour and characteristic absorption and EPR spectra. Laccases from the solid-state cultures were yellow-brown and had no typical blue oxidase spectra and also showed atypical EPR spectra. Comparison of N-terminal amino acid sequences of purified laccases showed high homology between blue and yellow-brown laccase forms. Formation of yellow laccases as a result of binding of lignin-derived molecules by enzyme protein is proposed. PMID- 9368356 TI - Protein secretion in Streptomyces griseus N2-3-11: characterization of the secA gene and its growth phase-dependent expression. AB - The chromosomal region encoding the secA gene of Streptomyces griseus N2-3-11 was cloned and analyzed. The secA gene encodes a polypeptide of 939 aa with a molecular mass of 105 kDa. The growth defect of temperature sensitive Escherichia coli secA mutants was not restored by the S. griseus SecA. The secA promoter was analyzed and the transcriptional start point of the gene was determined. Northern blot and Western blot analyses revealed a growth phase dependent secA expression. The integration of an additional copy of the S. griseus secA gene into the genome of S. lividans TK23 had no visible effect on the efficiency of protein secretion. PMID- 9368357 TI - Development of mycobacterial species-specific DNA probes by subtraction hybridization. AB - Subtraction hybridization was used to identify sequences of Mycobacterium bovis DNA which might be of diagnostic value. Genomic DNA from Mycobacterium avium, isolated commonly from cattle and whose tuberculin is used in the comparative intradermal tuberculin test, was subtracted from M. bovis genomic DNA. A novel sequence, of 131 bp, which appears to be Mycobacterium tuberculosis complex specific was identified. The specificity of this sequence was stringently tested by a probe and polymerase chain reaction (PCR) assay. Nucleotide identity determination and sequence comparisons revealed that the 131-bp sequence is located directly upstream of a potential isocitrate dehydrogenase (IDH) coding gene and may be of diagnostic value, enabling differentiation of M. tuberculosis complex mycobacteria from other mycobacterial species. PMID- 9368358 TI - Spirochaetes and other bacterial species associated with bovine digital dermatitis. AB - The 16S rRNA genes from spirochaetes associated with digital dermatitis of British cattle were amplified by polymerase chain reaction from digital dermatitis lesion biopsies using one universal and one treponeme-specific primer. Two treponemal sequences were identified both of which shared a high degree of homology with the oral pathogen Treponema denticola (98%). Two further 16S rRNA gene sequences were obtained and shared similarity to Bacteroides levii (99%) and Mycoplasma hyopharyngis (98%). Polymerase chain reaction with T. denticola specific primers amplified a potential virulence gene from digital dermatitis lesions which shared a high degree of homology to the 46-kDa haemolysin gene of T. denticola. The significance of the presence of organisms in digital dermatitis lesions of the bovine foot which are closely related to oral pathogens is discussed. PMID- 9368359 TI - Isolation of a nitric oxide synthase from the protozoan parasite, Leishmania donovani. AB - A soluble nitric oxide synthase (NOS) activity was purified 2800-fold from Leishmania donovani, the causative parasite of visceral leishmaniasis, by two step affinity and anion-exchange chromatography. The purified enzyme ran as a prominent band of 110 kDa on SDS-PAGE whereas gel filtration experiments estimated the native molecular mass to be 230 +/- 20 kDa indicating that the native enzyme exists as a dimer. The enzyme activity required NADPH and was blocked by EGTA. The enzyme kinetics, cofactor requirements, inhibition studies and Western blot analysis with brain anti-NOS antibody suggest its similarity with mammalian NOS isoform I. PMID- 9368360 TI - Insertion site of the locus of enterocyte effacement in enteropathogenic and enterohemorrhagic Escherichia coli differs in relation to the clonal phylogeny of the strains. AB - The locus of enterocyte effacement pathogenicity island confers the attaching and effacing histopathology on epithelial cells infected with enteropathogenic and enterohemorrhagic Escherichia coli. We investigated the site of insertion of the locus of enterocyte effacement in E. coli strains in relation to their evolution based on conservation of housekeeping proteins in these strains. The results indicate that the insertion site of the locus of enterocyte effacement varies according to the evolutionary lineage, suggesting that it has inserted at multiple times and sites during the evolution of these pathogens. PMID- 9368361 TI - Diversity of oxygen and N-oxide regulation of nitrite reductases in denitrifying bacteria. AB - We examined alpha, beta and gamma Proteobacteria with Cu and heme-type dissimilatory nitrite reductases for patterns of nir regulation. Six of seven strains expressed nitrite reductase under aerobic growth conditions. In only one strain, G-179, was it stringently regulated by O2. Growth with NO-3 or NO-2 enhanced nitrite reductase production in four of seven strains under anaerobic growth conditions, but in only one strain, Pseudomonas aeruginosa PA01, under aerobic conditions. In this strain the nitrite reductase production was primarily regulated by an anr gene when grown under anaerobic conditions, but when grown under aerobic conditions it was regulated by both an anr gene and nitrogen oxide. Constitutive production of nitrite reductase was a common phenomenon rather than the exception among denitrifiers from the environment, which helps explain the prevalence of denitrifying enzymes in aerobic soils. PMID- 9368362 TI - Identification and cloning of the Mycobacterium avium folA gene, required for dihydrofolate reductase activity. AB - Dihydrofolate reductase is an essential bacterial enzyme necessary for the maintenance of intracellular folate pools in a biochemically active reduced state. In this report, the Mycobacterium avium folA gene was identified by functional genetic complementation, sequenced, and expressed for the first time. It has an open reading frame of 543 bp with a G + C content of 73%. The translated polypeptide sequence shows 58% identity to the consensus sequence of the conserved regions from eight other bacterial dihydrofolate reductases. Recombinant M. avium dihydrofolate reductase was expressed actively in Escherichia coli, and SDS-PAGE analysis revealed a 20 kDa species, agreeable with that predicted from the polypeptide sequence: PMID- 9368364 TI - Ampicillin-induced bacteriolysis of Escherichia coli is not affected by reduction in levels of anionic phospholipids. AB - Anionic phospholipids have been shown to interact with both membrane-associated proteins and integral membrane proteins. The objective of this work was to determine whether bacteriolysis induced by treatment with ampicillin was influenced by the levels of anionic membrane phospholipids in Escherichia coli strain HDL11. The pgsA gene, encoding phosphatidylglycerophosphate synthase, in HDL11 is under the control of lacOP, and the levels of anionic membrane phospholipids are consequently dependent on IPTG. The results indicate that limiting the amounts of phosphatidylglycerol and cardiolipin did not affect the lysis process in both growing and nongrowing bacteria. PMID- 9368363 TI - Binding of Escherichia coli heat-stable enterotoxin and rise of cyclic GMP in COLO 205 human colonic carcinoma cells. AB - Escherichia coli heat-stable enterotoxin (STa) was found to bind on the surface of human colonic (COLO 205) cells. The binding of [125I]STa to cell membranes was found to be specific, reversible and saturable. Scatchard analysis of the equilibrium binding demonstrated a single class of binding sites with a Kd of 0.5 x 10(-10) M. Autoradiographic analysis of polyacrylamide gel electrophoresis revealed the specific incorporation of [125I]STa into a single STa binding protein with a molecular mass of 95 kDa. Following incubation of COLO 205 cells with STa, a rise of intracellular cGMP was also evident. PMID- 9368365 TI - High frequency gene transfer by microprojectile bombardment of intact conidia from the entomopathogenic fungus Paecilomyces fumosoroseus. AB - Two different methods, (i) PEG and (ii) biolistic, were employed to transform protoplasts and conidia of Paecilomyces fumosoroseus using hygromycin resistance as selectable marker. Transformation frequencies varied from 1.9 to 2.5 transformants microgram-1 of DNA by the PEG method, and from 33 to 153 transformants microgram-1 of DNA by the biolistic procedure. PMID- 9368366 TI - Isolation and characterization of an Azotobacter vinelandii algK mutant. AB - Random Tn5 mutagenesis over Azotobacter vinelandii mucoid strain ATCC 9046 produced strain LA21, a non-mucoid, non-encysting mutant, carrying the Tn5 insertion within a gene homologous to algK from Pseudomonas aeruginosa encoding a periplasmic protein. algK, algJ and algG were shown to be transcribed as part of the palg8-alg44-algK-algJ-algG operon. A non-polar algK mutant was constructed and showed a non-mucoid phenotype, indicating that algK is essential for alginate production. PMID- 9368368 TI - Inactivation of penicillin-induced staphylococcal L-forms by human serum high density lipoprotein. AB - In penicillin-susceptible bacteria, penicillin causes growth of a small fraction of cells as wall-deficient forms if an appropriate osmoprotection is provided (unstable L-forms). A subfraction of human serum high density lipoprotein (HDL3) was shown to have the ability to inactivate unstable L-forms of Staphylococcus aureus. The active principle was distinguishable from the well-documented trypanosome lytic factor 1 with respect to density, size, and other properties. This L-form cytotoxicity therefore seems to represent a novel antimicrobial entity in human serum. PMID- 9368367 TI - Disinfection of human enteric viruses on fomites. AB - The virucidal action of several commercially available disinfectant preparations was assayed against hepatitis A virus and human rotavirus dried on polystyrene. Overall, the level of virus disinfection achieved was very poor, usually inducing less than 3 log titre reduction. Suspension tests performed with the same disinfectants showed different virus inactivation rates, thus failing to provide a reliable indication of the actual virus disinfection on fomites. In our studies, bacteriophages of Bacteroides fragilis proved to be a simple, cheap and reliable screening tool for the evaluation of virus disinfection on non-porous surfaces. The same conclusion cannot be drawn for poliovirus. PMID- 9368369 TI - Identification of yebG as a DNA damage-inducible Escherichia coli gene. AB - The nucleotide sequence upstream of the Escherichia coli yebG gene presents features similar to those found in SOS system regulatory sites (putative SOS box, -10 and -35 promoter boxes and a ribosome binding site). Operon fusion assays demonstrate now that this region controls transcription in a recA-, lexA dependent way and that the reporter gene expression is inducible by DNA damage consequent to mitomycin C treatment. Increased expression does not result from an increase in plasmid copy number. These results indicate that yebG is a novel SOS regulon gene. The yebG product is predicted to be a 96 amino acid residue, 10.7 kDa protein whose function is not yet known. Unlike other SOS genes, the construct carrying the yebG regulatory region is not stationary phase inducible. PMID- 9368371 TI - The lom gene of bacteriophage lambda is involved in Escherichia coli K12 adhesion to human buccal epithelial cells. AB - The role of the lom gene of bacteriophage lambda in adhesion of Escherichia coli to human buccal epithelial cells (HBC) was studied testing the adherence of lamda lom+ and lambda lom::TnphoA E. coli lysogens. lambda lom+ prophage increased 50% E. coli adhesion. This effect was not observed with lambda lom::TnphoA. These results suggest that the normal Lom protein participates directly in adhesion or regulates the synthesis of other protein(s), which may be involved in adhesion. PMID- 9368370 TI - Genetic variation among Mycoplasma agalactiae isolates detected by the variant surface lipoprotein gene (vspA) of Mycoplasma bovis. AB - Multiple restriction fragments, homologous to the previously described Mycoplasma bovis vspA gene, were identified in the chromosome of Mycoplasma agalactiae. The vspA, a representative variable surface lipoprotein gene of the vsp gene family, and four synthetic oligonucleotides, representing sequences complementary to selected regions of the vsp genes, were used as probes against digested chromosomal DNAs of several M. agalactiae clinical isolates. The resulting Southern blot analysis demonstrated a marked DNA polymorphism of multiple vspA related fragments among the isolates. An oligonucleotide representing a conserved 5'-region common to all known vsp genes, was found to hybridize to multiple M. agalactiae genomic fragments while the other three oligonucleotides, representing distinct repetitive structures within the coding region of three known vsp genes (vspA, vspE, and vspF), failed to react. These results argue for the possible existence of a gene family in M. agalactiae analogous to the vsp system of M. bovis but comprised of diverse genes. PMID- 9368372 TI - Cloning and analysis of the glucosyl transferase gene encoding type I antigen in Shigella flexneri. AB - The O-antigen of most Shigella flexneri serotypes contains an identical tetrasaccharide repeating unit. Apart from serotype Y, the O-antigen is modified by addition of a glucosyl and/or O-acetyl residue to a specific position in the O unit. In this study the glucosyl transferase gene from a serotype 1 a has been cloned and identified. The bacteriophage SfV integrase (int) gene was used to probe a S. flexneri Y53 (serotype 1 a) cosmid library and 18 unique clones were identified. Southern hybridisation of these clones indicated two unlinked regions of the chromosome contained the int homologue. When expressed in a live candidate vaccine strain of S. flexneri serotype Y (SFL124), clones with one region produced type I antigen, whereas clones containing the other region produced mainly type Y antigen. One of the cosmid clones positive for type I antigen by agglutination and Western blotting was selected for further study. Genes involved in O-antigen glucosyl modification were mapped on a 5.8 kb fragment and subclones were produced which fully or partially expressed the type I antigen, depending on the extent of the clone. Fully and partially expressing clones may be useful vaccine candidate strains for protection against disease caused by two serotypes of S. flexneri. PMID- 9368373 TI - Growth of an Escherichia coli mutant deficient in respiration. AB - An Escherichia coli mutant deficient in genes for heme biosynthesis grew in medium of initial pH 8 containing 1% tryptone and glucose under aerobic growth conditions, and its doubling time was approximately 60 min at 37 degrees C. The growth rate was not increased under O2-limiting conditions. When the mutant was grown in medium of initial pH 6, growth stopped at the middle of the exponential growth phase. This could be overcome and the growth yield increased by the addition of 20 mM lysine to the growth medium. Lysine did not prevent the decrease in the medium pH as growth proceeded, making it unlikely that lysine decarboxylation stimulates growth by the alkalinization of the medium. These results indicate that respiration is not obligatory for growth under aerobic conditions, but growth without respiration at low pH requires a large amount of lysine. PMID- 9368374 TI - Cytochrome P-450 reductase is responsible for the ferrireductase activity associated with isolated plasma membranes of Saccharomyces cerevisiae. AB - Cytochrome P-450 reductase (encoded by the NCP1 gene) was found to catalyse all the NADPH-dependent ferrireductase activities associated with isolated plasma membranes of the yeast Saccharomyces cerevisiae. We therefore examined the contribution of this enzyme to the ferrireductase activity of cells in vivo. Cytochrome P-450 reductase was shown to be not essential for the cell ferrireductase activity, but it influenced this activity, with different effects on the Fre1- and the Fre2-dependent reductase systems. Overexpression of FRE1 did not lead to an increased ferrireductase activity of the cells when NCP1 was repressed. In contrast, cells that overexpressed FRE2 had maximal ferrireductase activity when NCP1 was repressed. The degree of NCP1 expression also affected the amount of iron and copper accumulated by the cells during growth. The biochemical implications and the physiological significance of these observations are discussed. PMID- 9368375 TI - Binding of the 51- and 42-kDa individual components from the Bacillus sphaericus crystal toxin to mosquito larval midgut membranes from Culex and Anopheles sp. (Diptera: Culicidae). AB - Individual components (P51 and P42) from the crystal toxin (Bin) of Bacillus sphaericus were used for in vitro binding competition experiments with brush border membranes (BBMFs) from Culex pipiens and Anopheles gambiae larval midguts. P51 competed for the Bin binding site with a similar affinity to the Bin toxin, on both BBMFs. For C. pipiens, P42 bound non-specifically until P51 was added with maximum binding of P42 at a molar ratio of each component. The binding of P42 was much greater on A. gambiae BBMFs and the presence of either P51 or P42 enhanced the binding of the other component, with highest binding when a mole ratio of each protein was supplied. PMID- 9368376 TI - Induction of surface-associated proteins of Streptococcus uberis by cultivation with extracellular matrix components and bovine mammary epithelial cells. AB - Surface-associated protein expression by Streptococcus uberis was influenced by the presence of collagen, laminin and bovine mammary epithelial cells in the culture medium. After electrophoresis and silver staining, four proteins stained more intensively in samples from S. uberis cultivated with epithelial cells and extracellular matrix components than in samples from S. uberis cultivated alone. Induction of these proteins was more obvious after multiple bacterial passages. The correlation between the phenotype of S. uberis and its potential virulence status as illustrated by an immunoblotting study with sera obtained from infected cows revealed that these proteins are probably expressed in vivo during infection. PMID- 9368377 TI - Human lactoferrin receptor activity in non-encapsulated Haemophilus influenzae. AB - Since the ability of bacteria to compete with lactoferrin for iron contributes to the pathogenesis of mucosal infections, the presence of lactoferrin receptor activity in non-encapsulated Haemophilus influenzae was investigated. The growth of 18 H. influenzae isolates from the sputum samples of chronic bronchitis patients and of six of seven H. influenzae throat isolates from healthy adults was stimulated by iron saturated human lactoferrin. Apo-lactoferrin did not stimulate the growth of H. influenzae. Human lactoferrin binding to iron limited bacteria was detected for 16 H. influenzae strains from chronic bronchitis patients and for five of seven isolates from healthy adults. We conclude that the majority of H. influenzae isolates tested bind human lactoferrin and that the iron from lactoferrin is used for growth. PMID- 9368378 TI - Application of capillary electrophoresis-fluorescence line-narrowing spectroscopy for on-line spectral characterization of closely related analytes. AB - Capillary electrophoresis (CE) interfaced with low-temperature (4.2 K) fluorescence line-narrowing spectroscopy (FLNS) is used for the separation and spectral characterization of closely related analytes. In this paper, the CE-FLNS system is applied to the analysis of a mixture of deuterated and protonated benzo[a]pyrene, a mixture of structurally similar benzo[a]pyrene and benzo[e]pyrene, and mixtures of dibenzo[a,l]pyrene-derived adenine DNA adducts. The CE-FLNS system provides on-line separation and high-resolution spectroscopic identification of CE-separated analytes, via fingerprint structure of vibrationally resolved FLN spectra at 4.2 K. The combination of the separation power of CE and the spectral selectivity of FLNS provide a methodology that has potential to become a powerful tool for molecular analyte characterization. The main applications of the CE-FLNS system, due to its selectivity, should be in the chemical analysis of structurally similar analytes and applications where analyte purity and detailed structural characterization are required. PMID- 9368379 TI - Determination of kynurenic acid by capillary electrophoresis with laser-induced fluorescence detection. AB - Kynurenic acid (KA) is an excitatory amino acid receptor antagonist that is believed to play an important role in a host of diseases of the neuropsychiatric and central nervous system. A method for the determination of KA in microdialysate samples using capillary electrophoresis (CE) separation with laser induced fluorescence (LIF) detection is described. CE is advantageous for the analysis of microdialysis samples due to its short analysis times and small sample volume requirements. Three complexation approaches were evaluated in an attempt to achieve the best limit of detection. The best approach was found to be pre-column complexation with inclusion of Zn(II) in the background electrolyte. After optimization of the zinc acetate concentration and pH, a limit of detection of 1 nM KA was achieved. However, when KA was present in the dialysate, the limit of detection increased 50-fold. Even though the endogenous levels of KA in rat brain are below this limit of detection, this methodology could be used to monitor the increase of KA levels in rat brain following dosing with its precursors, tryptophan and kynurenine. PMID- 9368380 TI - Interactions of the human class II major histocompatibility complex protein HLA DR4 with a peptide ligand demonstrated by affinity capillary electrophoresis. AB - The interactions of empty recombinant major histocompatibility complex (MHC) class II molecules (DRA1*0101/DRB1*0401) with a known peptide ligand [the HA(307 319) fragment of influenza virus hemagglutinin] were studied by capillary electrophoresis. Using an alkaline buffer system with the addition of non-ionic or zwitterionic detergent and high sensitivity laser-induced fluorescence detection, both slowly and rapidly equilibrating binding could be demonstrated. This was accomplished using a pre-equilibration approach as well as migration shift experiments where receptor molecules were added to the electrophoresis buffer. This system may be useful for the study of both peptide binding to MHC molecules and screening for inhibition or amplification of binding by other ligands as well as for the study of the interactions of T-cell receptors with MHC peptide complexes. PMID- 9368381 TI - Capillary electrophoresis with electrospray mass spectrometry detection for low molecular-mass compounds. AB - Mass spectrometry (MS) detection using electrospray ionization (ESI) has been explored for the separation by capillary electrophoresis (CE) of a number of sample mixtures containing low-molecular-mass species. Optimal sheath liquid composition has been determined using a peptide mixture in which femtomolar quantities of analyte were easily observed. Effects of CE buffer choice were studied in detail. Also, a separation of basic drugs in cough syrup has been successfully detected by ESI-MS. Using negative ionization, a mixture of alkyl sulfonates and a mixture of food dyes were analyzed. All components were easily resolved and identified by molecular weight. PMID- 9368382 TI - Effects of electroosmotic flow on zone mobilization in capillary isoelectric focusing. AB - The electroosmotic mobilization of focused protein zones in a fused-silica capillary is investigated using a mixture of model proteins, including alpha chymotrypsinogen A (bovine pancreas), myoglobin (horse heart) and carbonic anhydrase II (bovine erythrocytes). The presence of carrier ampholytes in the entire capillary and the adsorption of carrier ampholytes onto the capillary wall almost eliminate the electroosmotic flow in the fused-silica capillary, obviating the need for polymer additives such as methylcellulose and hydroxypropylmethylcellulose. In fact, the electroosmotic displacement of focused protein zones can only be achieved by injecting a mixture of proteins and ampholytes as a plug at the inlet of a capillary that has been pre-filled with the catholyte. Various approaches for protein mobilization in the uncoated capillary completely filled with carrier ampholytes are studied. The addition of methylcellulose to the sample mixture of carrier ampholytes and protein analytes serves as an anticonvective medium during the gravity mobilization step and contributes to the reduction of protein adsorption onto the capillary wall. PMID- 9368383 TI - Enantiomer separation of acidic racemates by capillary electrophoresis using cationic and amphoteric beta-cyclodextrins as chiral selectors. AB - Enantiomer separations of various acidic racemates were performed by capillary electrophoresis (CE) using a commercial cationic beta-cyclodextrin (beta-CD), quaternary ammonium beta-CD (QA-beta-CD), and a commercial amphoteric beta-CD (AM beta-CD) as chiral selectors. Eleven acidic racemates were successfully separated using QA-beta-CD by changing the CD concentration and the buffer pH. These enantiomer separations were compared with the results using five neutral CD derivatives. Although most racemates were separated with some of the neutral CDs, relatively high CD concentrations were required to obtain baseline separations. In contrast, when QA-beta-CD was employed, the enantiomer separations were successful at low concentrations below 5 mM. Enantiomers of five acidic racemates and ten dansylated amino acids (Dns-amino acids) were separated using AM-beta-CD. Although the baseline separation of racemic 4-chloromandelic acid was not achieved with either QA-beta-CD or five neutral CDs, AM-beta-CD showed complete resolution. Furthermore, the simultaneous enantiomer separation of eight Dns amino acids was also achieved with AM-beta-CD. Both QA-beta-CD and AM-beta-CD were analyzed by CE and mass spectrometry (MS) in order to identify their compositions because they consisted of a mixture having different degrees of substitution. QA-beta-CD consisted of six components having from one to six quaternary ammonium groups. The composition of AM-beta-CD, however, was very complicated and could not be identified. PMID- 9368385 TI - Capillary electrochromatography: theories on electroosmotic flow in porous media. AB - In view of the present interest in capillary electrochromatography (CEC), theories dealing with electroosmotic flow (EOF) in porous media are reviewed with particular regard to the use of packed capillaries in CEC. Two of the models found in the pertinent literature are applicable to CEC and give simple analytical solutions. The first of the two models is based on von Smoluchowski's work as adapted and extended by Overbeek. It deals with EOF through packed capillaries under conditions of low electric field strength where the EOF varies linearly with the field strength because there is no polarization of the double layer. Overbeek's model originally developed for porous media of infinite dimensions was modified in an attempt to account for the wall effect that assumes importance in the packed capillary columns used in CEC. The second model proposed by Dukhin and his coworkers predicts EOF of at least an order of magnitude higher than that expected by classical theories. This "electroosmosis of the second kind" is believed to occur in columns packed with conductive particles like ion exchangers at high electric field strengths when the double layer is polarized and the EOF becomes a non-linear function of the applied voltage. Conditions necessary for electroosmosis of the the second kind are likely to arise upon the further development of CEC when further enhancement of the speed of analysis is brought about at electric field strength higher than that employed at present. PMID- 9368384 TI - Dynamics of capillary electrochromatography experimental study on the electrosmotic flow and conductance in open and packed capillaries. AB - For capillary electrochromatography (CEC) to become an analytical separation technique of high speed and resolution the factors determining the conductivity of the column as well as the generation and control of electrosmotic flow (EOF) in porous media have to be understood. In the present study the conductance of capillaries packed with a variety of stationary phases was evaluated with respect to the conductance of the open capillary and the data were interpreted in the light of the Tobias equation. However, the consistently observed reduction of the EOF when a capillary having a charged inner wall is packed with particles having charges of the same sign and the dependence of the EOF velocity on the particle size needs further explanation. The data suggests that, due to the employment of relatively long columns packed with small particles, CEC may offer peak capacities much higher than HPLC or micro-HPLC. The CEC columns are unique as they consist of a packed and an open capillary segment having different conductances and consequently different voltage gradients and electrical field strengths. Therefore, any sufficiently detailed study on CEC systems requires also the characterization of the individual column segments. EOF velocities of 6 7 mm/s could be realized at 60 kV applied voltage with a 23/32 cm x 50 microns raw fused-silica capillary packed with 6-micron Zorbax ODS particles. The current was a linear function of the field strength up to 1.8 kV/cm, but at high field strengths the EOF increased with squared field strength. Data on band spreading indicate that with a given column the plate height at high EOF velocities is smaller in CEC than in micro-HPLC and it is weakly dependent on the velocity. PMID- 9368386 TI - Automated microanalysis using magnetic beads with commercial capillary electrophoretic instrumentation. AB - The potential of a new microanalytical method using magnetic beads (MBs) and commercial capillary electrophoresis (CE) instrumentation for performing enzymatic and inhibition assays, as well as for analysis of biological molecules such as antigens, substrates, etc., has been explored. A small quantity of magnetic beads containing immobilized biomolecules was injected into a neutral hydrophilic-coated fused-silica capillary. The short plug (2-3 mm) of beads was held fixed by a magnet placed in the cartridge of the CE system, without the use of frits. The beads could be replaced after each run, eliminating the need to regenerate the solid support. Two protocols were used for analysis: sequential injection (SI) and SI followed by isotachophoretic (ITP) focusing. Alkaline phosphatase (AP) and HIV-protease were used to demonstrate the SI procedure for enzymatic and inhibition assays. The second protocol, SI/ITP, was employed to quantitate an antigen (mouse mAB) using antibodies (sheep IgG towards mouse AB) immobilized on the beads. The MB-CE method, requiring only femtomole (fmol) quantities of material, can potentially be employed in diagnostic and forensic assays, kinetic studies and searching for inhibitors, ligands, receptors, etc. PMID- 9368387 TI - Quaternary structural analysis of nucleoside diphosphate kinases using capillary electrophoresis. AB - Capillary electrophoresis was used to monitor the quaternary structure and structural changes by denaturants of nucleoside diphosphate kinase (NDP kinase). NDP kinase from human erythrocyte consists of two kinds of polypeptide chains: A (Nm23-H1) and B (Nm23-H2), which are the products of nm23-H1 and -H2 genes, respectively. Structural characteristics of native NDP kinase, recombinant Nm23 H1 and -H2 were examined using capillary electrophoresis employing high pH running buffer in an uncoated fused-silica capillary as a separation column. The results were compared with those of the conventional sodium dodecyl sulfate and non-denaturing polyacrylamide gel electrophoresis. It shows that capillary electrophoresis is a possible tool to investigate protein structure, including the quaternary structure. This protocol was applied to the investigation of the denaturation process of each enzyme by denaturants (6 M urea or heating to 70 degrees C) and to the monitoring of the interaction between denatured Nm23-H1 and -H2. The structural information of NDP kinase obtained by analysis using capillary electrophoresis is valuable for understanding its suggested biological function as a tumor metastasis suppressor and c-myc transcription factor, etc. PMID- 9368388 TI - Application of capillary electrophoresis to determination of enzyme activity and other properties of phosphatidylinositol-specific phospholipase C. AB - This paper describes a method for monitoring enzymatic activity using micellar electrokinetic chromatography (MEKC). MEKC is used to analyze the activity of phosphatidylinositol-specific phospholipase C (PI-PLC) with convenience and precision. PI specific PLC enzyme converts phosphatidylinositol (PI) to diacylglycerol (DAG) and inositol 1,2-cyclic phosphate (IP). The assay system developed is based on monitoring both the breakdown of substrate and the formation of products simultaneously. To obtain the best separation for the substrate PI and product DAG, we investigated changes in concentration of electrolyte buffer and SDS as well as in pH of the electrolyte buffer. Since the structures of the substrate and products are different, the reaction could be monitored easily by MEKC mostly based on hydrophobicity. Under the separation conditions developed, we investigated the enzymatic activity of PI-PLC depending on the concentrations of phosphatidylinositol, various divalent cations and the reaction temperature. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used to confirm the molecular masses of the substrate PI and products DAG and IP. The results of this study show that capillary electrophoresis can be widely applied to analyze and characterize many other enzymes since capillary electrophoresis has several advantages as follows, simplicity, speed, no need for radiolabelled substrate, small sample volumes and sufficient accuracy. PMID- 9368389 TI - Microchip-based capillary electrophoresis of human serum proteins. AB - The separation and relative quantitation of human serum proteins is important to the clinical diagnosis of various states of disease. Microchip-based capillary electrophoresis (CE) of human serum proteins offers several advantages over sodium dodecyl sulfate-poly(acrylamide) gel electrophoresis and conventional CE methods, including decreased sample consumption and analysis time and the possibility of on-chip sample manipulation (dilution, labelling, etc.). The microchip used in these studies was designed to allow for on-chip, post separation labelling of the proteins and subsequent laser-induced fluorescence detection. 2-Toluidinonaphthalene-6-sulfonate (TNS) is a virtually non fluorescent reagent which, upon non-covalent association with the protein and excitation at 325 nm, produces a fluorescent product with an emission maximum near 450 nm. After optimization of buffer conditions (100 mM borate with 2 mM lactate, pH 10.5), individual serum proteins (IgG to mimic the gamma zone, transferrin the beta zone, alpha-1-antitrypsin the alpha 1 zone and albumin its own zone) were successfully resolved on-chip, as was a "synthetic" serum solution composed of a mixture of all four of the previously mentioned proteins. Analysis of all five protein zones in a true human serum sample, however, has not yet been achieved on-chip due to the poor sensitivity of the TNS label for several of the serum proteins. PMID- 9368390 TI - Protein band spreading in capillary zone electrophoresis effects of sample zone length and presence of polymer. AB - It is commonly accepted that intra-column zone dispersion in CZE rests on multiple mechanisms, viz. diffusion, interaction of analyte with the capillary walls, Joule heat and conductivity differences between sample zone and the surrounding buffer. The most important extra-column contributor to bandwidth is thought to be the starting zone width. The present study shows that the length of the starting zone above 10 mm is linearly related to the bandwidth of R phycoerythrin (M(r) 290.10(3)). Below that length, bandwidth demonstrates a plateau preceded by a slight rise. Within the 'plateau range', the ratio of bandwidth to effective capillary length is close to constant while it is independent of electric field strength in the range of 37 to 370 V cm-1 and of protein concentration in the range of 0.1 to 1000 micrograms ml-1. The experimental observations support the notion that the analyte-wall interaction is the determining source of intra-column zone dispersion. A slight rise observed at initial zone lengths of less than 2 mm was accounted for by a diffusion model taking into account a non-local initial concentration of analyte. The presence of polyethyleneglycol in the buffer within a concentration range up to 6% does not affect bandwidth. Above that concentration, the level of constant bandwidth is raised. PMID- 9368391 TI - Conventional capillary electrophoresis in comparison with short-capillary capillary electrophoresis and microfabricated glass chip capillary electrophoresis for the analysis of fluorescein isothiocyanate anti-human immunoglobulin G. AB - Fast, efficient analysis of fluorescein isothiocyanate anti-human IgG was achieved in a short-capillary and in a microfabricated glass chip. The capillary was 6 cm long from injection end to detector with electric field strength of 0.268 kV/cm. Analyses were performed within 1 min. A glass microchip device was fabricated using standard photolithographic procedures and chemical wet etching. The channels were sealed using a direct bonding technique. For an effective length of 2.8 cm with electric field strength of 0.526 kV/cm, electrophoretic analysis was achieved in less than 16 s. Conventional capillary electrophoresis gave highly reproducible results and good detection limits. Analysis time was 2.5 min for a capillary with 47 cm effective length and electric field strength of 0.383 kV/cm. PMID- 9368392 TI - Rapid sizing of polymorphic microsatellite markers by capillary array electrophoresis. AB - Genetic mapping and DNA sequencing projects could potentially be completed more rapidly by using capillary array electrophoresis (CAE) systems running 48-96 capillaries simultaneously. Currently, multiplex polymerase chain reaction (PCR) and multicolor fluorescent dye-labeling strategies are used to generate DNA profiles containing 18-24 genotypes per sample. By using 4-color fluorescence detection and these multiplex PCR strategies, a CAE system has the capacity to generate up to 5.5 million genotypes per year. CAE offers extremely fast, high resolution separation of DNA and more automated sample processing than conventional systems because the labor-intensive slab-gel pouring and sample loading steps are eliminated. We used a prototype CAE system in an ongoing linkage analysis study of inherited deafness in Mediterranean families. CA-repeat markers linked to deafness susceptibility genes on chromosomes 7, 11 and 13 were analyzed and DNA profiles generated which contain 6 markers per color. Fragment sizes of over 28,000 short tandem repeat alleles and 3200 CA-repeat alleles have been determined by CAE. An average sizing precision of +/- 0.12 base pairs (bp) for fragments up to 350 bp was realized in 1-h runs. In addition, a versatile non denaturing matrix was used to separate DNA sizing standards, restriction digests, and multiplex PCR samples. Application of this matrix to Duchenne muscular dystrophy exon deletion screening is also described. These CAE approaches should facilitate rapid genotyping of microsatellite markers and subsequent identification of disease-causing mutations. PMID- 9368393 TI - Method for detection of epsilon-secondary structure in the precore region of human hepatitis B virus DNA using a fluorescence-based polymerase chain reaction single-strand-conformation polymorphism technique with capillary electrophoresis. AB - A portion of the precore region of the human hepatitis B virus (HBV) genome is the signal sequence with an epsilon secondary structure, which plays a role in the encapsidation of HBV pregenome RNA. To determine the genetic mutations which occur in the precore region of HBV, we have devised a typing method using a fluorescence-based polymerase-chain-reaction-single-strand conformation polymorphism technique with automated capillary electrophoresis (CE-FSSCP). Using the cloning sequencing method, we analyzed serum samples from 10 patients with hepatitis B, and detected three types of HBV-DNA including two mutants which are crucial to the function of the encapsidation sequence: position 1896 G (guanine) to A (adenine, stop codon), position 1899 G to A, and wild-type. We performed CE FSSCP analysis of these three types of HBV-DNA and described conditions for determination of the mutations which play roles in the encapsidation of the HBV pregenome. The two types of epsilon mutants and wild-type DNA were identified as separate individual peaks respectively. The observed migration times of the three types of DNAs agreed fairly well with estimates obtained from total RNA secondary structure energy. PMID- 9368394 TI - Separation of DNA sequencing fragments up to 1000 bases by using poly(ethylene oxide)-filled capillary electrophoresis. AB - We have demonstrated that DNA bases up to 1000 base pairs (bp) in a sequencing ladder can be separated using poly(ethylene oxide)-filled capillary electrophoresis (resolution of raw data = 0.5 at 966 bp). Separation performance of this sieving matrix has been tested under different experimental conditions. It was found that the electric field strength played a critical role in the onset of reptation and thus the separation efficiency. Optimized gel composition and concentration is required for good separation, but the total gel concentration should lie between 2.5 and 3.0%. We observed that the capillary length influences the number of theoretical plates and the maximum readable length of DNA. For sequencing up to 500 bp, relatively nonviscous solutions can be used, greatly facilitating the replacement of the sieving matrix in between runs. PMID- 9368395 TI - Application of mixed mobile phases and a step gradient method in capillary electrochromatography for the separation of isomeric polycyclic aromatic hydrocarbon-deoxyribonucleoside adduct mixtures prepared in vitro. AB - Capillary electrochromatography (CEC) was used for the analysis of mixtures of neutral isomeric compounds derived from the reaction of carcinogenic hydrocarbon (benzo[g]chrysene and 5,6-dimethylchrysene) dihydrodiol epoxides with calf thymus deoxyribonucleic acid (DNA). The CEC analysis demonstrated higher resolution, greater speed and lower analyte consumption than high-performance liquid chromatography (HPLC) in the analysis of the same samples using the same type of stationary phase. Proper selection of the mixed mobile phases was critical for the separation of these complex mixtures with enhanced speed and selectivity. The use of a step gradient further improved the speed of the CEC analysis resulting in electrochromatograms that required only 25-70% of the corresponding HPLC analysis times. PMID- 9368396 TI - Capillary electrophoresis for the detection of known point mutations by single nucleotide primer extension and laser-induced fluorescence detection. AB - Capillary electrophoresis (CE) with laser-induced fluorescence (LIF) was used to detect known point mutations using the method of single-nucleotide primer extension (SNuPE). Three different point mutations in human mitochondrial DNA associated with Leber's hereditary optic neuropathy (LHON) were detected by annealing a primer immediately 5' to the mutation on the template and extending the primer by one fluorescently labeled dideoxy terminator complementary to the mutation. By using two or more differently labeled terminators, both the mutant and wild type could be simultaneously detected. The advantages of using CE-LIF for detecting SNuPE reactions include speed and ease of analysis, absence of radioactivity, and potential for automation. PMID- 9368397 TI - Analysis of nitrate in biological fluids by capillary electrophoresis. AB - Nitrite and nitrate represent the products of the final pathway of nitric oxide metabolism. These two ions were analyzed by capillary electrophoresis (CE) in serum, cerebrospinal fluid, urine and tissue homogenates by mixing the sample with acetonitrile containing NaBr as an internal standard, followed by centrifugation. The supernatant was injected hydrodynamically on a capillary 50 cm x 75 microns (I.D.) and electrophoresed at 6 kV (reversed polarity) in 1.4% sodium chloride in phosphate buffer for 13 min with detection at 214 nm. In addition to removal of the proteins, acetonitrile caused sample stacking. Urinary nitrate analysis by CE was compared to that by the enzymatic Aspergillus nitrate reductase method, with a correlation coefficient of 0.96. PMID- 9368398 TI - Study of the enzymatic transformation of fluorescently labeled oligosaccharides in human epidermoid cells using capillary electrophoresis with laser-induced fluorescence detection. AB - Isomeric oligosaccharides of both beta Gal(1-->3)beta GlcNAc (type I) series and beta Gal(1-->4)beta GlcNAc (type II) series were studied by using capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection. A mixture of phenylboronic acid and sodium tetraborate was used in the CE running buffers to improve the electrophoretic separation of the oligosaccharides. Both series of the tetramethylrhodamine (TMR)-labeled substrates [beta Gal(1-->3)beta GlcNAc-O TMR and beta Gal(1-->4)beta GlcNAc-O-TMR) and their potential enzymatic products were baseline resolved using CE. The high resolution provided by CE and the excellent detection limit (8.10(-23) mol, or 50 molecules) by LIF allowed for the determination of minor enzyme products in the presence of excess unreacted substrate. The action of competing enzymes acting on the common type I sequence was monitored after the incubation of human epidermoid carcinoma cells (A431) with a fluorescent substrate (beta Gal(1-->3)beta GlcNAc-O-TMR). The CE-LIF analyses showed the formation of both synthetic and hydrolytic products, suggesting the actions of glycosyltransferases and glycosidases in the cells. PMID- 9368399 TI - Exoglycosidase matrix-mediated sequencing of a complex glycan pool by capillary electrophoresis. AB - This paper discusses oligosaccharide sequencing by consecutive enzymatic digestion of carbohydrates using an exoglycosidase array, followed by capillary electrophoresis separation of the digests. Because of the high resolving power and good reproducibility of capillary electrophoresis, multistructure sequencing of a complex glycan pool can be performed in most instances requiring no prior isolation of the individual oligosaccharides. High sensitivity laser-induced fluorescence detection enables acquisition of complete sequence information from several picomoles of glycoproteins. Comparison of the migration times of the exoglycosidase digest fragments to the maltooligosaccharide ladder, enables calculation of migration shifts, due to cleavage based on the actual exoglycosidases used. The particular sequence of each oligosaccharide in a glycan pool can be proposed with high confidence based on the migration time shifts of the various oligosaccharide structures. However, possible combinations of various sequence fragments may have very similar charge to hydrodynamic volume ratios, resulting in electrophoretic co-migration when a mixture of different oligosaccharides is sequenced together. Then, capillary electrophoresis separations of the resulting fragments should be evaluated after each digestion step. In the instances of complex separation profiles when multiple peaks are present, the evaluation of peak shifts can get very complicated and solved only with the aid of a software program. Data about the monosaccharide composition of the glycan pool provides useful information in designing the digestion enzyme matrix. PMID- 9368400 TI - Analysis of recombinant human growth hormone directly in osmotic shock fluids. AB - An isocratic reversed-phase high-performance liquid chromatography (RP-HPLC) method for the determination of human growth hormone (hGH) directly in osmotic shock fluids is described. This methodology allows an initial rapid evaluation of the quality and quantity of hGH being secreted in the bacterial periplasmic space right after, or even during fermentation. Considering that RP-HPLC does not identify size isomers, these were determined via a parallel run of the same osmotic shock fluid on high-performance size-exclusion chromatography, coupled with radioimmunoassay, of the eluted fractions. The methodology provides a complete picture, within 24 h from the beginning of the fermentation process, of the recombinant protein being produced with respect to its activity, identity, yield, and hGH-related contaminants. These latter include sulfoxide and desamido derivatives, dimer and high-molecular-mass forms. PMID- 9368404 TI - Qualitative and quantitative high-performance liquid chromatographic analysis of aldehydes in Brazilian sugar cane spirits and other distilled alcoholic beverages. AB - A study is presented on the high-performance liquid chromatographic analysis of eighteen aldehydes in Brazilian sugar cane spirits and other international brandies. The aldehydes were separated by reversed-phase high-performance liquid chromatography as 2,4-dinitrophenylhydrazones (DNPHs). A very good chromatographic separation was achieved for eighteen different aldehyde-DNPHs. The proposed methodology is quite simple and not very time-consuming. Ten aldehydes were identified in 75 beverages and quantified using the external standard method with UV detection at 365 nm. A detailed knowledge of the aldehyde content should significantly contribute to improving the quality control of distilled spirits. PMID- 9368405 TI - Purification of monoclonal antibodies by epitope and mimotope affinity chromatography. AB - Murine monoclonal antibodies raised against the carcinoma-associated MUC1 mucin have applications in the diagnosis and therapy of human cancer. Many of these antibodies define linear epitopes of three, four or five amino acids within an immunodominant region of the MUC1 protein core. Various synthetic peptides which incorporated this region were prepared and covalently linked to agarose beads for use as affinity matrices. An unrelated peptide was identified as a mimotope for one of the anti-MUC1 antibodies using phage display technologies and this was also evaluated as a potential ligand in an affinity matrix. Epitope affinity chromatographic purification of an anti-MUC1 antibody was performed using hybridoma tissue culture supernatants as sample. Following sample application and column washing, antibody was desorbed from the matrix by gradient elution with increasing concentrations of NaSCN. The procedure has proved efficient for the purification of anti-MUC1 antibodies and the concentration of NaSCN required for antibody desorption gives a measure of the relative binding affinity of the antibody for the peptide epitope matrix so that separation strategies may be optimised. PMID- 9368406 TI - Model of in vitro granulomatous hypersensitivity in human paracoccidioidomycosis. AB - With the purpose of studying the immunological components of granulomatous hypersensitivity in patients infected with Paracoccidioides brasiliensis, we used the model of in vitro granuloma formation developed for schistosomiasis studies, that correlates with in vivo granulomatous reactivity occurring around eggs trapped in organs of infected donors. In this case, granuloma formation can be determined examining cellular reactivity manifested as multiple cell layers surrounding antigen-conjugated polyacrilamide beads. Our results showed that peripheral blood mononuclear cells (PBMC) obtained from acute treated and chronic paracoccidioidomycosis patients proliferate and generate in vitro granulomas in response to P. brasiliensis antigens (PbAg). In contrast, no proliferation or granuloma formation were observed when PBMC from acute non-treated patients were used. These studies demonstrate the feasibility of investigating granulomatous hypersensitivity in P. brasiliensis-infected patients by using an in vitro granuloma model. PMID- 9368407 TI - Prevalence, epidemiology and geographical distribution of Sporothrix schenckii infections in Gauteng, South Africa. AB - Sporotrichosis is a subcutaneous fungal infection caused by the traumatic implantation of the dimorphic, pathogenic fungus, Sporothrix schenkii. It constitutes the most common subcutaneous fungal infection in the general population in South Africa. Sporotrichosis in South Africa dates back to 1914, when the disease was first diagnosed in the gold mines. Occupational and recreational circumstances of infection are well established, and the environmental requirements for contracting the disease are better understood. Sporotrichosis cases were recorded from 42 suburbs in the greater Pretoria area as well as from 23 towns outside the Pretoria municipal boundary. It occurred in 154 patients with ages ranging from less than 1 year to 90 years old, with males predominating. Females in the area seemed to be at lesser risk, mainly becoming infected through gardening injuries, insect bites or other minor injuries due to outdoor activities. Exposure to possible sources of the fungus, either from recreational or occupational activities in males, was the main determining factor in acquiring the disease. The lymphocutaneous and localized forms of the disease were most often recorded. Our study indicates that, while there is no pronounced seasonal variation, the onset of the disease seemed to be mainly in the cooler and dryer months of the year. PMID- 9368408 TI - Chromoblastomycosis--a clinical and mycological study of 71 cases from Sri Lanka. AB - Chromoblastomycosis, a well-documented chronic fungal infection, represents a specific clinical entity with typical warty cutaneous nodules and a worldwide distribution. Although more prevalent in tropical and subtropical regions, only a few reports are available from Sri Lanka or from Asia. Five etiologic agents of chromoblastomycosis have been recognized worldwide. Of these the majority of infections have been caused by Fonsecaea pedrosoi. During the period from 1952 to 1962, only twelve culturally proven cases of this disease had been recorded from Sri Lanka. The fungus responsible was F. pedrosoi. The present report presents a study of the clinical and mycological features of 71 Sri Lankan patients with chromoblastomycosis for the 16-year period from 1978 to 1993. It documents three etiological agents. Culture identification was made in 69 cases. The three fungal species were Fonsecaea pedrosoi (64), Phialophora verrucosa (3) and a fungus compatible morphologically with F. compacta (2). The isolation of a fungus morphologically compatible with F. compacta is of significance since only 12 cases have been documented in the world's literature so far. PMID- 9368409 TI - Evaluation of the AUXACOLOR system for the identification of clinical yeast isolates. AB - In the last decade the number of systemic yeast infections has increased significantly. Although Candida albicans is the most frequently isolated yeast from clinical specimens, the emergence of non-albicans species has clearly been a recent concern. As a consequence, there is a greater need for rapid and accurate methods for yeast identification. The aim of this study was to evaluate the performance of the AUXACOLOR system (Sanofi Diagnostics Pasteur) for the identification of clinically relevant yeasts, as compared with the conventional method. Yeast isolates (n = 97) belonging to 12 species were identified by the commercial system and the classic method. Correct identifications were obtained by using AUXACOLOR system in 79.4% of the isolates tested. Misidentification occurred in 5.2% of the strains and 15.5% were not identified due to a failure in the manufacturer's data base. In order to improve its accuracy, there is a need for expanding the database or revamping the tests included in the system. PMID- 9368410 TI - Mycoflora and incidence of aflatoxin B1, zearalenone and deoxynivalenol in poultry feeds in Argentina. AB - In Argentina, there is rather little information about the natural occurrence of mycotoxins in feedstuffs. The aim of this work was to determine the fungal flora and natural incidence of aflatoxin B1 (AFB1), zearalenone (ZEA) and deoxynivalenol (DON) in poultry feeds from 5 factories of Rio Cuarto, Cordoba. Three hundred samples were taken from May 1995 to May 1996. Fungal counts of poultry feeds ranged 10(4) to 10(6) CFU g-1. The lowest counts were obtained on the first months from the sampling (May to September 1995) with mean values significantly different from those found at the last of the sampling (October 1995 to April 1996). The most prevalent species isolated of poultry feed samples belonged to the genera Penicillium that was present in 98% of the samples, Fusarium (87%) and Aspergillus (52%). Fusarium species isolated were: F moniliforme in 73% of the samples, F subglutinans (35%), F graminearum (20%) and within Aspergillus species: A. parasiticus (33%) and A. flavus (8%) were identified. In poultry feeds aflatoxin B1 (AFB1) was the most significant mycotoxin with levels ranging from 17 to 197 ng/g. For deoxynivalenol (DON) the levels ranged from 240 to 410 ng/g. Only three out of 300 samples were contaminated with zearalenone (ZEA) in concentrations of 30, 120 and 280 ng/g. These are preliminary data on this subject in our region. PMID- 9368411 TI - Wounding changes the spatial expression pattern of the arabidopsis plastid omega 3 fatty acid desaturase gene (FAD7) through different signal transduction pathways. AB - The Arabidopsis FAD7 gene encodes a plastid omega-3 fatty acid desaturase that catalyzes the desaturation of dienoic fatty acids in membrane lipids. The mRNA levels of the Arabidopsis FAD7 gene in rosette leaves rose rapidly after local wounding treatments. Wounding also induced the expression of the FAD7 gene in roots. To study wound-responsive expression of the FAD7 gene in further detail, we analyzed transgenic tobacco plants carrying the -825 Arabidopsis FAD7 promoter beta-glucuronidase fusion gene. In unwounded transformants, FAD7 promoter activity was restricted to the tissues whose cells contained chloroplasts. Activation of the FAD7 promoter by local wounding treatments was more substantial in stems (29-fold) and roots (10-fold) of transgenic plants than it was in leaves (approximately two-fold). Significant induction by wounding was observed in the overall tissues of stems and included trichomes, the epidermis, cortex, vascular system, and the pith of the parenchyma. Strong promoter activity was found preferentially in the vascular tissues of wounded roots. These results indicate that wounding changes the spatial expression pattern of the FAD7 gene. Inhibitors of the octadecanoid pathway, salicylic acid and n-propyl gallate, strongly suppressed the wound activation of the FAD7 promoter in roots but not in leaves or stems. In unwounded plants, exogenously applied methyl jasmonate activated the FAD7 promoter in roots, whereas it repressed FAD7 promoter activity in leaves. Taken together, wound-responsive expression of the FAD7 gene in roots is thought to be mediated via the octadecanoid pathway, whereas in leaves, jasmonate independent wound signals may induce the activation of the FAD7 gene. These observations indicate that wound-responsive expression of the FAD7 gene in aerial and subterranean parts of plants is brought about by way of different signal transduction pathways. PMID- 9368412 TI - Promoter trap markers differentiate structural and positional components of polar development in Arabidopsis. AB - To investigate mechanisms involved in establishing polar organization in Arabidopsis embryos and seedlings, we used promoter trapping to identify molecular markers (beta-glucuronidase fusion genes) expressed in spatially restricted patterns along the apical-basal axis. Three markers were identified that are expressed, respectively, in the embryonic and seedling root tip (POLARIS), cotyledons and shoot and root apices (EXORDIUM), and root cap (COLUMELLA). Each marker was crossed into the mutants hydra and emb30, which are defective in embryonic and seedling morphogenesis. All three markers were expressed in hydra mutants in patterns similar to those observed in phenotypically wild-type embryos and seedlings. In emb30 mutants, the EXORDIUM marker was expressed in cotyledons but not in the expected position of shoot and root meristems, and the marker COLUMELLA was not expressed at all, which is consistent with the view that the emb30 mutant, but not hydra, lacks shoot and root meristems. However, POLARIS was expressed in the basal part of hydra embryos lacking an embryonic root and in the basal parts of both hydra and emb30 seedlings. Expression of POLARIS is inducible by exogenous auxin and suppressed by cytokinin but is unaffected by inhibitors of polar auxin transport or cell division. We conclude that POLARIS differentiates positional aspects of polar development from structural aspects. PMID- 9368413 TI - Attenuation of phytochrome A and B signaling pathways by the Arabidopsis circadian clock. AB - In higher plants, environmental cues such as light signals are integrated with circadian clock signals to control precisely the daily rhythms observed for many biological functions. We have used a fusion of the promoter of a chlorophyll a/b binding protein gene, CAB2, with firefly luciferase (cab2::luc) to monitor the detailed kinetics of transcription in response to photoreceptor activation in Arabidopsis. Using this marker in phototransduction and circadian-dysfunctional mutants, we studied how signals from phytochrome and the circadian clock are integrated for the regulation of CAB2 transcription. Results from these mutant studies demonstrate that similar expression features, namely, the acute and circadian responses, are present in both etiolated and green seedlings and that the acute and circadian responses are genetically separable. We also demonstrate that persistent Pfr signaling occurs in red light-pulsed etiolated seedlings, which suggests that the circadian clock antagonizes Pfr-mediated signal transduction. Based on these genetic studies, we propose a model for the regulation of CAB2 transcription in which individual photoreceptors and phototransduction components have been assigned to specific pathways for the regulation of discrete kinetic components of the CAB2 expression pattern. PMID- 9368414 TI - Tag1 is an autonomous transposable element that shows somatic excision in both Arabidopsis and tobacco. AB - Tag1 is a transposable element first identified as an insertion in the CHL1 gene of Arabidopsis. The chl1::Tag1 mutant originated from a plant (ecotype Landsberg erecta) that had been transformed with the maize transposon Activator (Ac), which is distantly related to Tag1. Genomic analysis of untransformed Landsberg erecta plants demonstrated that two identical Tag1 elements are present in the Landsberg erecta genome. To determine what provides transposase function for Tag1 transposition, we examined Tag1 excision in different genetic backgrounds. First, the chl1::Tag1 mutant was backcrossed to untransformed wild-type Arabidopsis plants to remove the Ac element(s) from the genome. F2 progeny that had no Ac elements but still retained Tag1 in the CHL1 gene were identified. Tag1 still excised in these Ac-minus progeny producing CHL1 revertants; therefore, Ac is not required for Tag1 excision. Next, Tag1 was inserted between a cauliflower mosaic virus 35S promoter and a beta-glucuronidase (GUS) marker gene and transformed into tobacco. Transformants showed blue-staining sectors indicative of Tag1 excision. Transgenic tobacco containing a defective Tag1 element, which was constructed in vitro by deleting an internal 1.4-kb EcoRI fragment, did not show blue-staining sectors. We conclude that Tag1 is an autonomous element capable of independent excision. The 35S-GUS::Tag1 construct was then introduced into Arabidopsis. Blue-staining sectors were found in cotyledons, leaves, and roots, showing that Tag1 undergoes somatic excision during vegetative development in its native host. PMID- 9368415 TI - Arabidopsis mutants resistant to the auxin effects of indole-3-acetonitrile are defective in the nitrilase encoded by the NIT1 gene. AB - Indole-3-acetonitrile (IAN) is a candidate precursor of the plant growth hormone indole-3-acetic acid (IAA). We demonstrated that IAN has auxinlike effects on Arabidopsis seedlings and that exogenous IAN is converted to IAA in vivo. We isolated mutants with reduced sensitivity to IAN that remained sensitive to IAA. These mutants were recessive and fell into a single complementation group that mapped to chromosome 3, within 0.5 centimorgans of a cluster of three nitrilase encoding genes, NIT1, NIT2, and NIT3. Each of the three mutants contained a single base change in the coding region of the NIT1 gene, and the expression pattern of NIT1 is consistent with the IAN insensitivity observed in the nit1 mutant alleles. The half-life of IAN and levels of IAA and IAN were unchanged in the nit1 mutant, confirming that Arabidopsis has other functional nitrilases. Overexpressing NIT2 in transgenic Arabidopsis caused increased sensitivity to IAN and faster turnover of exogenous IAN in vivo. PMID- 9368417 TI - The 14-3-3 protein interacts directly with the C-terminal region of the plant plasma membrane H(+)-ATPase. AB - Accumulating evidence suggests that 14-3-3 proteins are involved in the regulation of plant plasma membrane H(+)-ATPase activity. However, it is not known whether the 14-3-3 protein interacts directly or indirectly with the H(+) ATPase. In this study, detergent-solubilized plasma membrane H(+)-ATPase isolated from fusicoccin-treated maize shoots was copurified with the 14-3-3 protein (as determined by protein gel blotting), and the H(+)-ATPase was recovered in an activated state. In the absence of fusicoccin treatment, H(+)-ATPase and the 14-3 3 protein were well separated, and the H(+)-ATPase was recovered in a nonactivated form. Trypsin treatment removed the 10-kD C-terminal region from the H(+)-ATPase as well as the 14-3-3 protein. Using the yeast two-hybrid system, we could show a direct interaction between Arabidopsis 14-3-3 GF14-phi and the last 98 C-terminal amino acids of the Arabidopsis AHA2 plasma membrane H(+)-ATPase. We propose that the 14-3-3 protein is a natural ligand of the plasma membrane H(+) ATPase, regulating proton pumping by displacing the C-terminal autoinhibitory domain of the H(+)-ATPase. PMID- 9368416 TI - Effect of the nuclear factors EmBP1 and viviparous1 on the transcription of the Em gene in HeLa nuclear extracts. AB - Templates constructed from the wheat Em and maize rab28 promoters are efficiently and accurately transcribed in the well-characterized cell-free transcription system prepared from HeLa nuclei. Deletion analysis of the Em promoter indicates that a G-box (CACGTG) element (Em1b) is required for transcription. USF, a Myc transcription factor in HeLa nuclear extracts, activates transcription by binding to Em1b, as shown by the ability of an antibody raised against USF to inhibit transcription and to interfere with Em1b complex formation in an electrophoretic mobility shift assay. The addition of the recombinant Viviparous1 protein from maize to HeLa nuclear extracts specifically stimulated transcription of the Em promoter but was dependent on the presence of USF in the extract. In USF-depleted extracts, the addition of recombinant EmBP1, a basic leucine zipper transcription factor from wheat, activated transcription through Em1b as well as from a similar G-box in the adenovirus major late promoter. Our study demonstrates that the basic transcriptional apparatus in HeLa nuclear extract supports transcription from plant promoters and can be used to assay the function of certain plant nuclear proteins, thereby helping to determine their effects on transcription. PMID- 9368418 TI - Expression of a Cs(+)-resistant guard cell K+ channel confers Cs(+)-resistant, light-induced stomatal opening in transgenic arabidopsis. AB - Inward-rectifying K+ (K+in) channels in the guard cell plasma membrane have been suggested to function as a major pathway for K+ influx into guard cells during stomatal opening. When K+in channels were blocked with external Cs+ in wild-type Arabidopsis guard cells, light-induced stomatal opening was reduced. Transgenic Arabidopsis plants were generated that expressed a mutant of the guard cell K+in channel, KAT1, which shows enhanced resistance to the Cs+ block. Stomata in these transgenic lines opened in the presence of external Cs+. Patch-clamp experiments with transgenic guard cells showed that inward K+(in) currents were blocked less by Cs+ than were K+ currents in controls. These data provide direct evidence that KAT1 functions as a plasma membrane K+ channel in vivo and that K+in channels constitute an important mechanism for light-induced stomatal opening. In addition, biophysical properties of K+in channels in guard cells indicate that components in addition to KAT1 may contribute to the formation of K+in channels in vivo. PMID- 9368419 TI - Role of arabidopsis MYC and MYB homologs in drought- and abscisic acid-regulated gene expression. AB - In Arabidopsis, the induction of a dehydration-responsive gene, rd22, is mediated by abscisic acid (ABA) and requires protein biosynthesis for ABA-dependent gene expression. Previous experiments established that a 67-bp DNA fragment of the rd22 promoter is sufficient for dehydration- and ABA-induced gene expression and that this DNA fragment contains two closely located putative recognition sites for the basic helix-loop-helix protein MYC and one putative recognition site for MYB. We have carefully analyzed the 67-bp region of the rd22 promoter in transgenic tobacco plants and found that both the first MYC site and the MYB recognition site function as cis-acting elements in the dehydration-induced expression of the rd22 gene. A cDNA encoding a MYC-related DNA binding protein was isolated by DNA-ligand binding screening, using the 67-bp region as a probe, and designated rd22BP1. The rd22BP1 cDNA encodes a 68-kD protein that has a typical DNA binding domain of a basic region helix-loop-helix leucine zipper motif in MYC-related transcription factors. The rd22BP1 protein binds specifically to the first MYC recognition site in the 67-bp fragment. RNA gel blot analysis revealed that transcription of the rd22BP1 gene is induced by dehydration stress and ABA treatment, and its induction precedes that of rd22. We have reported a drought- and ABA-inducible gene that encodes the MYB-related protein ATMYB2. In a transient transactivation experiment using Arabidopsis leaf protoplasts, we demonstrated that both the rd22BP1 and ATMYB2 proteins activate transcription of the rd22 promoter fused to the beta-glucuronidase reporter gene. These results indicate that both the rd22BP1 (MYC) and ATMYB2 (MYB) proteins function as transcriptional activators in the dehydration- and ABA-inducible expression of the rd22 gene. PMID- 9368421 TI - Mapping elasticity of rehydrated metaphase chromosomes by scanning force microscopy. AB - Scanning force microscopy was used for mapping the viscoelastic properties of metaphase chromosomes. These properties were probed by scanning with various imaging forces and subsequent calculation of the difference image. The procedure allows a mapping of the viscoelastic behavior expressed as force-dependent indentation of the local surface feature and results in an image with material contrast. The approach is demonstrated on rehydrated metaphase chromosomes, which were spread and air-dried before rehydration in aqueous buffer. The rehydration resulted in a swelling of the chromosome structure and was accompanied by drastic changes in the viscoelastic properties. For comparisons, force-distance curves on metaphase chromosomes were accumulated; these curves were also used for the calculation of the stiffness curve. The demonstrated approach of mapping viscoelasticity by differential scanning force microscopy allows the detection of domains with varying mechanical properties in biomolecules such as chromosomes. PMID- 9368420 TI - Protein quality control along the route to the plant vacuole. AB - To acquire information on the relationships between structural maturation of proteins in the endoplasmic reticulum (ER) and their transport along the secretory pathway, we have analyzed the destiny of an assembly-defective form of the trimeric vacuolar storage glycoprotein phaseolin. In leaves of transgenic tobacco, where assembly-competent phaseolin is correctly targeted to the vacuole, defective phaseolin remains located in the ER or a closely related compartment where it represents a major ligand of the chaperone BiP. Defective phaseolin maintained susceptibility to endoglycosidase H and was slowly degraded by a process that is not inhibited by heat shock or brefeldin A, indicating that degradation does not involve transport along the secretory pathway. These results provide evidence for the presence of a quality control mechanism in the ER of plant cells that avoids intracellular trafficking of severely defective proteins and eventually leads to their degradation. PMID- 9368422 TI - Mental health considerations with the Yupik Eskimo. AB - In cross-cultural mental health, there is a need to understand the culture from which a person belongs before psychotherapy can be effective. The Yupik (Siberian) Eskimos of the St. Lawrence Island area have several historical traumas that have effected their cultural group. This paper addresses some of the important factors that have formed personality features of the Yupik. Discussion centers on the mental health factors inherent in the cultural shift and historical traumas that have occurred from the 1800s to the present, including traditional livelihood, family role patterns, and education. This particular cultural shift is one of traditional independence to European dependence. PMID- 9368423 TI - Nutritional rickets among breast-fed black and Alaska Native children. AB - Although nutritional rickets remains a problem primarily in developing countries, children in northern climates in developed countries may also be at risk. We reviewed the case histories of five children diagnosed in Alaska during 1993-96. Three of the children were black and two Alaska Native. Their ages ranged from 11 to 20 months and they presented during January, April, and September. All of the children were breast-fed but only two received their milk intake exclusively from breast milk. The presenting complaint included abnormal gait in two children and seizures, bowed legs, and growth delay in one child each. All five children demonstrated a decrease in their height-for-age percentile. The most common physical finding was a rachitic rosary which was present in four children. In Alaska, all black and Alaska Native children (and other more pigmented children) less than two years of age who receive all or part of their milk intake from breast milk should receive vitamin D supplementation regardless of the time of year. PMID- 9368424 TI - Does it make sense to heat gases higher than body temperature for the treatment of cold water near-drowning or hypothermia? A point of view paper. AB - There appears to be several areas of concern relating to the continued use of heating gases higher than body temperature for the treatment of cold water near drowning. The use of heated gases as a primary means to rewarm a hypothermic patient does not seem to be any more effective than doing nothing at all. These low rewarming rates translate into some very long resuscitations. Even Dr. Nemiroff, who was a strong advocate of using heated humidified gases for treating cold water near-drowning, did not consider the use of warm inspired gases to be a primary rewarming technique. He referred to the use of heated humidified gases as a, "stabilization technique". However, does it make sense to use a technique that is several times slower than other methods of similar complexity? Does it make sense to use a protocol that may in fact lower a hypothermic patient's basal metabolic rate? There are some major patient safety issues raised by heating gases to high levels. However, there have not been many patients with documented airway damage. I have several hypothesis about why this is so. Few people seem to know how to significantly heat their patient's circuit. If they devise a system that gets to the therapeutic range they usually have second thoughts when the bag valve-mask is too hot to hold, or the plastic wide bore tubing begins to melt, they will reduce the system temperature on that basis alone. Many of the hypothermic patients who are intubated simply do not have good survival rates, and so we may underestimate the degree of airway damage that occurs. Spontaneously breathing patients will tend to refuse to breathe hot gases which limits their potential for airway damage. However, is this a risk we need to run? Would it not make more sense to heat the inspired gases to close to body temperature and avoid the problem? I feel that the time has come for the Respiratory Therapy community to come together and work on this problem. The researchers have done their jobs in providing us with reasonable data on which to base a clinical decision. It would seem to me that if a Clinical Practice Guideline for cold water near-drowning or hypothermia were in place it might provide the other groups impetus for updating their guidelines. The bottom line is that patients deserve the best care that we know how to provide, and a clear set of guidelines is an essential first step. PMID- 9368425 TI - Physician impairment and health: a brief overview. PMID- 9368426 TI - Careful facility "downsizing" reduces liability risks. Use of inexperienced or unqualified staff threatens patients safety. PMID- 9368427 TI - The great American sell-a-thon. PMID- 9368428 TI - A second opinion. PMID- 9368430 TI - Telling the patient. PMID- 9368429 TI - Detecting oral cancer. PMID- 9368431 TI - Cancer awareness. PMID- 9368432 TI - Cosmetic gum grafting. PMID- 9368433 TI - New caries-fighting substances. PMID- 9368434 TI - Complex medical devices. PMID- 9368435 TI - In your dental practice, is dental amalgam still the restorative material of choice? PMID- 9368436 TI - In vitro elution of leachable components from dental sealants. AB - Recent concerns have been raised about the possibility that estrogenic chemicals, in particular bisphenol-A, or BPA, might be leached out of dental sealants. This study aimed to identify and quantify BPA and other components released from seven light-cured fissure sealants in vitro. None of the tested sealants was shown to have released BPA; however, the investigators identified other eluted components that should be investigated for their biological effects. PMID- 9368437 TI - Nd:YAG laser irradiation of infected root canals in combination with microbiological examinations. AB - In this in vivo study, 30 subjects with infected root canals were treated with the neodymium: yttrium-aluminum-garnet, or Nd:YAG, laser using standard laser settings and procedures. In microbiological examinations conducted before irradiation, the authors found streptococci in 30 cases and staphylococci in 15 cases. After the first irradiation, the authors found that 19 root canals showed minimal streptococcal growth and 10 root canals showed minimal staphylococcal growth. PMID- 9368438 TI - Examining patients' responses about the effectiveness of five denture adhesive pastes. AB - In this clinical trial, the authors evaluated the responses of 25 experienced denture wearers in regard to the effectiveness of five denture adhesive pastes. The patients responded to questions about the effect of the pastes on quality and duration of retention as well as on mastication. Subjects were also asked which product they considered to be best. Eighteen (72 percent) of the 25 subjects rated Secure (John O. Butler Co.) denture adhesive paste best overall. PMID- 9368439 TI - The endodontic-periodontal continuum revisited: new insights into etiology, diagnosis and treatment. AB - For many decades, investigators have conducted studies of the interrelationship between endodontics and periodontics. This review article examines previously held concepts regarding the endodontic-periodontal continuum in light of new research and explores promising advances in understanding etiology and in diagnosis and treatment. PMID- 9368440 TI - Adenoid cystic carcinoma of the maxillary sinus. AB - A patient was referred by her dentist to the author for the evaluation of a left palatal mass and orofacial anesthesia. The author diagnosed a maxillary sinus malignancy and anesthesia of the maxillary branch of the left trigeminal nerve. Thoroughly examining the maxillary sinus of each patient who has anesthesia of the maxillary branch of the left trigeminal nerve is important in the early detection of adenoid cystic carcinoma. PMID- 9368441 TI - Dentistry and hypertension. AB - The author monitored the systolic and diastolic blood pressure, or BP; mean arterial pressure, or MAP; and heart rate, or HR, of hypertensive and normotensive patients once each minute during dental procedures. He found statistically significant differences in the means of the initial five and final five systolic BP and diastolic BP, MAP and HR readings. Exceptions were the HR in 18- to 45-year-old normotensive patients and the systolic BP in hypertensive patients. The author concluded that the time at which BP is monitored during a dental procedure may be significant. PMID- 9368442 TI - Accidental orthodontic elastic band-induced periodontitis: orthodontic and laser treatment. AB - The periodontal effects of elastic bands in the subgingiva have been reported since 1870. Case reports illustrate the treatment of elasticband-induced periodontitis in two children with a combination of laser treatment, antibiotics, splinting and orthodontics. Follow-up evaluations show reattachment, maturation of the apical portion of the roots, improved radiographic bone levels and minimal sulcus depth, mobility and recession. Continued orthodontic and periodontic care is planned. PMID- 9368443 TI - Improving communication with the laboratory when fabricating porcelain veneers. PMID- 9368444 TI - Preventing mouth mirrors from fogging. PMID- 9368445 TI - Overcoming challenges with resin in Class II situations. PMID- 9368446 TI - Chronic disabling diseases and disorders: the challenges of fibromyalgia. PMID- 9368447 TI - Death of a dentist. PMID- 9368448 TI - Navigating TennCare's appeals process. PMID- 9368449 TI - More than a pretty picture on the wall. PMID- 9368450 TI - Big problem--small hospital emergency department. PMID- 9368451 TI - Twin-twin transfusion syndrome with severe hydrops and anemia of the recipient twin following aggressive amnioreduction. PMID- 9368453 TI - The role of antiplatelet therapy in stroke prevention. PMID- 9368452 TI - Pulmonary autograft replacement of the aortic valve and root: a case report of the Ross procedure. PMID- 9368454 TI - Primary care within the VA: the firm model. AB - Many of the VA medical centers are reorganizing total care across a continuum that includes outpatient, inpatient, long-term, and home based care, into interdisciplinary firms. The goals of reorganization are to improve patient access to care and continuity of care, to improve housestaff education by assigning a specific panel of patients for the residents to follow longitudinally in a variety of situations supervised by the same mentors, and to enhance research in primary care issues. Preliminary results show increased patient satisfaction and improvements in both quality of care and increased efficiency in its delivery. Many large health care organizations might be expected to reorganize care delivery around a similar interdisciplinary team concept. PMID- 9368455 TI - Patient management following possible rabies exposure. PMID- 9368456 TI - A woman with difficulty swallowing. PMID- 9368458 TI - The winds of change in medicine. PMID- 9368457 TI - Women physicians: an education. PMID- 9368460 TI - Profiles of Wisconsin women in medicine. PMID- 9368459 TI - A woman's place in medical history. PMID- 9368461 TI - Lessons learned from a mentoring program for teenage mothers. AB - PURPOSE: This study evaluated a mentoring program designed to decrease the risk of repeat pregnancy among unmarried primiparous teens, ages 12-19. METHODS: Adolescents (n = 110) completed a battery that assessed sexual/contraceptive behavior; psychological adjustment; and attitudes towards school. Teens were then randomly assigned to a mentor or control group, and reassessed at 6, 12, 18, and 24 months. Mentored teens received social support and assistance dealing with community agencies from mentors who were trained community volunteers. RESULTS AND CONCLUSIONS: At baseline, mentor and control teens had similar sexual histories, school achievement profiles (percentage enrolled, cumulative grade point average), and anticipated being the same age when they had a second child. At 24 months (n = 81), most mentor and control teens were making progress in school. Fifty percent had graduated or had advanced two grades; 10 of the 16 graduating teens were seeking additional education. However, the mentoring program did not significantly impact repeat pregnancy rates. At 33 months, 66.0% of the mentored teens and 68.8% of the control teens had experienced a repeat pregnancy. Thirty-six percent of teens had one repeat pregnancy; 24% had two or more pregnancies. Sixty-two percent of the pregnancies with known resolution (89) resulted in live births; 26% were aborted. In providing this mentoring program, several important lessons were learned. PMID- 9368462 TI - Varicella in pregnancy. PMID- 9368463 TI - What's new in ... pediatric immunizations. PMID- 9368464 TI - Gender found to play little role in differential AMI treatment rates. PMID- 9368465 TI - Physician deselection: what it means for you. PMID- 9368466 TI - Temenos lost: reflections on moving. AB - This article examines some clinical dilemmas engendered by moving. At such times, certain patients (or the analysts themselves) may lose their sense of containment that the therapeutic space has provided. When such a disruption threatens the course of treatment, this changed condition may be archetypally termed 'temenos lost'. Consideration of this condition has led the author to reconceptualize healing as composed of two distinct components: the healing relationship and the healing space. Together, these components define the healing archetype. Using two historical examples, the King's Evil in Tudor England and healing pilgrimages in Israel, he shows how each component may indeed operate independently. More often, however, they function together. Using an extended published case (Volkan 1984), the author examines various aspects of how patients and analysts cope with 'temenos lost'. He emphasizes the importance of the emotional atmosphere in the physical setting, anticipatory anxiety of losing the temenos, and the basic anxiety that the move will damage the analysis. The importance of the rite of re entry for the patient is emphasized as a symbolic way of resolving 'temenos loss' that permits a healing move into a 'temenos regained'. PMID- 9368467 TI - Klein's archaic Oedipus complex and its possible relationship to the myth of the labyrinth: notes on the origin of courage. AB - The ancient Greek myth linking the images of the labyrinth and the Minotaur provides an allegory for Melanie Klein's conception of the archaic Oedipus complex as well as a vivid illustration of Winnicott's notions of object usage and the 'subjective object'. The labyrinth is suggestive of mother's body as the first area for an infant's exploration and putative sadistic conquest. The Minotaur, in turn, suggests the infant's unconscious phantasies about the content of mother's body, namely such projective identifications onto that body as the paternal penis and the 'internal babies'. Further, the heroic dynamic personified by Theseus in the myth of the labyrinth metaphorically signifies what is here proposed as a developmental line that involves the courage to do a number of things, including to become, to create, to seek, to explore, to do, to challenge, to undertake risks, to accept, to rescue, to initiate, to think, to know and to realize. The Minotaur can thus be thought to serve as a universal subjective signifier for an 'Object of Challenge', which, if not successfully dealt with by the ego-development of the infant, transforms that default into the 'Object of Nemesis'. Ultimately, this myth of mastery speaks to the psychoanalytic process itself as well as casting light on the transformative aspects of sexual intercourse as a personal healing ritual. PMID- 9368468 TI - Jungian constructivism and the value of uncertainty. AB - Introducing the basic assumptions of constructivism as a philosophical position, this paper illustrates how Jung's psychology-especially complex, archetype and transcendent function-is consonant with constructivism. Further, the paper explores some clinical implications of constructivism by reviewing the problems of chronic projective-identification in a stalemated analytic case, drawing on the contributions of Winnicott, Ogden and Modell in expanding our understanding of, and facility with, the transcendent function. PMID- 9368469 TI - Internal objects--a theoretical analysis of Jungian and Kleinian models. AB - In this paper I discuss the ways in which experimental and objective research from cognitive science and developmental psychology can help analysts evaluate the theoretical models of mental objects which we use; I indicate the ways in which such evidence tends to support models of internal objects as mental representations or developmental capacities rather than as wish-fulfilling expressions of instinctual drives. This kind of empirical evidence is not just of academic interest but also has direct clinical relevance, particularly with borderline patients; such patients' sense of identity is totally dependent on the analyst's understanding of their internal world and for this to be misunderstood by the analyst can be catastrophic. An accurate theoretical model of mental objects can therefore help analysts to contain their patients more effectively. PMID- 9368470 TI - Donald F. Sandner (6 June 1928-30 March 1997). PMID- 9368471 TI - [Diabetes mellitus. Importance of early diagnosis, appropriate management and control]. PMID- 9368472 TI - [Reconsideration of the therapy of coronary heart disease is needed. Symposium: "Prevention and Treatment of Coronary Disease", part of the 103rd Congress of the German Society of Internal Medicine. Wiesbaden, 6 April 1997]. PMID- 9368473 TI - [Innovative cost containment strategies in antibiotic therapy. Press conference "Cost containment in antibiotic therapy--new pharmaco-economic concepts". Munich, 20 June 1997]. PMID- 9368474 TI - Guide to Physical Therapist Practice. Part 1: A description of patient/client management. Part 2: Preferred practice patterns. American Physical Therapy Association. PMID- 9368475 TI - Functional expression of MDR-1 in acute myeloid leukemia: correlation with the clinical-biological, immunophenotypical, and prognostic disease characteristics. AB - Up till now, clinical data on the possible prognostic influence of multidrug resistance (MDR) in hematological malignancies have been inconsistent, probably due to technical pitfalls. Moreover, in most studies qualitative information on the presence/absence of MDR-1 expression has been used instead of quantitative results. In addition, results usually refer to the total BM population and not specifically to blast cells. In the present study we analyzed the expression of MDR-1 in a series of 50 newly diagnosed de novo AML using a double-staining technique: (a) monoclonal antibodies for the specific identification of blast cells and (b) the rhodamine-123 efflux assay, which allows a quantitative and calibrated measurement of MDR-1 function. Expression of MDR-1 was correlated with clinical, biological, and immunophenotypical disease characteristics. All patients were uniformly treated according to the AML 87/91 protocols of the Spanish Pethema Cooperative Group; the median age was 51 +/- 19 years and the FAB distribution was as follows: 2 M0, 9 M1, 9 M2, 12 M3, 11 M4, 5 M5, and 2 M6 cases. Upon grouping the 50 AML patients analyzed according to the level of rh123 elimination, it was observed that those cases with > or = 30% decrease in rh123 fluorescence displayed higher WBC counts (9 +/- 12 vs 37 +/- 73 x 10(9)/l, p = 0.02) and platelet numbers (94 +/- 11 vs 35 +/- 25 x 10(9)/l, p = 0.02), together with a higher incidence of extramedullary involvement (35% vs 24%, p = 0.02). Half of the patients (47%) displaying a low rh123 elimination (< 30%) showed M3 morphology, while among the 33 patients with a higher rate of rh123 elimination (> or = 30%), only four (12%) corresponded to the M3 morphological subtype (p = 0.0006). From the immunophenotypic point of view, a low rate of rh123 elimination was associated with a lower expression of HLADR antigen (p = 0.003) and a higher expression of CD117 (p = 0.01). Regarding the possible prognostic influence of MDR1 expression, we found that a high rate of rh123 elimination (> 30%) was associated with a tendency towards poor disease outcome, illustrated by both a lower complete remission rate with the first cycle of chemotherapy (36% vs 56%) and a lower median disease-free survival (22 months vs median DFS not reached), although differences did not reach statistical significance (p = 0.1 in both comparisons). This data shows that although MDR-1 can be a relevant parameter in the evaluation of AML patients, larger series of patients using appropriate techniques for specifically analyzing the MDR of blast cells will be necessary in order to establish the final clinical value of this parameter. PMID- 9368476 TI - Absence of mutations in the RET gene in acute myeloid leukemia. AB - Expression of the tyrosine kinase receptor RET has previously been detected in normal hematopoietic cells, and especially in cells of the myeloid lineage. Furthermore, RET was shown to be differentially expressed in acute myeloid leukemia (AML), a disease characterized by excessive cell growth and aberrant maturation of cells, with the highest levels of expression in leukemias with monocytic differentiation. RET is known to be expressed in cells from the excretory system and from the developing central and peripheral nervous system. Both activating and inactivating aberrations in the RET gene have been detected in disorders derived from these tissues. To investigate whether the differential expression is a primary defect in AML, the presence of RET alterations was scanned by Southern blot analysis on DNA of blasts obtained from 17 AML patients. However, no RET gene aberrations were found. Subsequently, denaturing gradient gel electrophoresis (DGGE) analysis was performed on the DNA of blasts from ten selected cases. All five variants detected turned out to represent neutral DNA polymorphisms, including a novel polymorphism in exon 14. Since we were unable to detect mutations of RET in AML, it is unlikely that it plays an important role in leukemogenesis. PMID- 9368477 TI - Prognostic significance of dysplastic features of hematopoiesis in patients with de novo acute myelogenous leukemia. AB - The detection of dysplastic features of hematopoiesis in de novo acute myeloid leukemia (AML) by light microscopy is defined as AML with trilineage myelodysplasia (AML/TLMD). The prognostic relevance of these dysplastic features for patients with de novo AML remains unclear. In order to evaluate the role of dysplasia in de novo AML, bone marrow aspirates from 69 patients were analyzed prospectively and investigated separately for erythropoiesis, granulopoiesis and megakaryopoiesis by three independent investigators. The overall complete remission (CR) rate was 48.8% and partial remission (PR) or nonresponders constituted 52.2% of the patients investigated. The median overall survival time was 5 months with a disease-free interval of 3.5 months for all patients. Dysgranulopoiesis (DysG) was observed in 30.4%, dysmegakaryopoiesis (DysM) in 50.7%, and dyserythropoiesis (DysE) in 43.5%. Of all patients, 26.0% showed trilineage dysplastic features and were thus classified as AML/TLMD. A significantly worse prognosis (Kaplan-Meyer plot, Student's t-test) was calculated for those patients with detection of only DysG (p = 0.002), DysM (p = 0.02), DysE (p = 0.04) as compared with patients without any dysplastic signs. An unfavorable karyotype was correlated with patients showing DysG (P = 0.02) and DysM (P = 0.04). For these patients with an unfavorable karyotype, the occurrence of any dysplastic features had no additional prognostic impact. Dysplastic features (DysG, DysM, DysE) seem to be an important prognostic factor in de novo AML correlating with short overall survival. DysG and DysM correlated well with the appearance of unfavorable chromosomal abnormalities. It may be reasonable to assume that patients with dysplastic features should be considered for more aggressive treatment schedules at the time of diagnosis. PMID- 9368478 TI - C1 esterase inhibitor concentrate for capillary leakage syndrome following bone marrow transplantation. AB - The prognosis of patients with severe capillary leakage syndrome (CLS) after bone marrow transplantation (BMT) is dismal despite aggressive use of intensive care therapy. Because the activated classical pathway of complement and relatively low levels of C1 esterase inhibitor (C1 INH) activity are known features in these patients, we evaluated the efficacy of a therapy using purified, human C1 INH concentrate. Severe CLS was defined as increase in body weight by more than 3% within 24 h combined with generalized edema, impaired hemodynamic system (tachycardia and/or decreased blood pressure), and non-responsiveness to furosemide. Of 142 patients, 22 developed severe CLS. The first seven patients whom we diagnosed with this complication were assessed as control patients. Fifteen patients with severe CLS were treated with C1 INH concentrate using a cumulative dose of 180 units/kg body wt. (initial dose: 60 units/kg, followed by two doses at 30 units/kg and four doses at 15 units/kg, every 12 h). The survival rate of patients with CLS was 57% at 1 year after BMT in the C1 INH treatment group, compared with 14% in the control group (p = 0.008). Eight of 15 treated patients are alive at a median of 9 months (range: 4-55) after BMT. The plasma levels of the complement activation parameters C4d and C5a were 3 +/- 1.1 mg/dl (mean +/- S.D.) and 0.3 +/- 0.1 microgram/l, respectively, prior to BMT, increasing to 8.2 +/- 2.1 mg/dl and 1.3 +/- 0.4 micrograms/l, respectively, at diagnosis of CLS. After infusion of C1 INH concentrate the plasma levels of C5a and C4d normalized. The activity of C1 INH rose to 139 +/- 10% of normal human plasma NHP pool (mean +/- S.D.) after infusion. The CH50 values were not significantly altered. The fluid status normalized within 11 days in 14 of 15 treated patients. The results of this study suggest that therapy with C1 INH concentrate improves the prognosis of patients with CLS after BMT. This has to be confirmed in a randomized, controlled trial. PMID- 9368479 TI - Flow-cytometric analysis of peripheral blood lymphocytes in patients with chronic idiopathic neutropenia of adults. AB - Flow-cytometric analysis of peripheral blood lymphocytes was performed in 96 patients with chronic idiopathic neutropenia of adults (CINA) and in 36 age- and sex-matched healthy volunteers (controls) using a panel of monoclonal antibodies. Patients were classified arbitrarily into group A (68 patients with 2500-1500 neutrophils/microliter) and group B (28 patients with neutrophil counts below 1500/microliter). We found that CINA patients displayed low numbers of peripheral blood lymphocytes compared with the controls, which correlated with the numbers of circulating neutrophils. This decrease was due mainly to the reduction of T lymphocytes and, to lesser degree, to the decline of NK cells. Both CD4+ and CD8+ T cells decreased, so that the CD4+/CD8+ cell ratio remained within normal range. Moreover, decrease of T lymphocytes was due essentially to the diminution of CD45RO+ T-cell subsets (CD4+/CD45RO+ and CD8+/CD45RO+), while CD45RA+ T cells did not change. A highly significant positive correlation was found between the numbers of CD45RO+ T cells and the numbers of circulating neutrophils. All these alterations were more pronounced in the patients of group B than in those of group A. NK cells were found to be significantly reduced in the patients of group B, but not in those of group A. The numbers of both CD16+ and CD56+ cells correlated with the numbers of circulating neutrophils. Patients of group B had also low numbers of CD57+ cells, probably due to the reduction of T cells and NK cells. B cells did not change significantly. No significant changes were found also in the numbers of lymphocytes carrying activation-related cell surface markers. We concluded that lymphocyte reduction in CINA patients is due mainly to the diminution of CD45RO+ cells, and we postulated that the most probable explanation for this abnormality is an increased extravasation of these cells, which pass into the tissues following an accelerated adhesion to endothelial cells. This hypothesis and its relationship with the underlying neutropenia in CINA patients remain to be clarified. PMID- 9368480 TI - Alloantibody from a patient with severe von Willebrand disease inhibits von Willebrand factor-FVIII interaction. AB - The aim of this study was to analyze the ability of an alloantibody from a patient with severe von Willebrand disease (vWD) to interfere with the vWF domain for FVIII, to inhibit factor VIII (FVIII), and to compare it with a rabbit polyclonal antibody. The vWF domain for binding to FVIII was assayed by a method previously described but using recombinant FVIII (r-FVIII, Kogenate), which contains no vWF, instead of Hemofil M (HM). Rabbit or human antibodies towards FVIII (FVIII-Ab) were analyzed using microtiter wells with immobilized r-FVIII through a monoclonal anti-FVIII antibody and an ELISA method. IgG from plasma of a patient with hemophilia A and FVIII inhibitor was used as a positive control. Normal human and rabbit IgGs were included as negative controls. Human vWD alloantibody IgG and the rabbit anti-vWF antibody IgG reacted with immobilized normal vWF, inhibiting its binding to r-FVIII in a dose-dependent manner, which suggests that it is specific. Normal human IgG fraction, as well as nonspecific rabbit IgG, did not interfere with this binding at all. The monoclonal antibody used in this assay to immobilize vWF did not alter this interaction at all. Human vWD alloantibody IgG and the rabbit antibody against vWF showed a partial inhibitory activity to plasma FVIII as well as r-FVIII. The inhibition reached a plateau with residual FVIII activity. FVIII-Ab were not detected in human alloantibody or in rabbit antibody preparations. In contrast, hemophiliac FVIII inhibitor showed FVIII-AB. This human vWD alloantibody behaves like polyclonal heterologous antibodies, and their inhibition of FVIII seems to be nonspecific due to a steric hindrance mechanism provided that both have no FVIII antibodies. PMID- 9368481 TI - Thrombotic events are not exclusive to the remission induction period in patients with acute lymphoblastic leukemia: a report of two cases of cerebral sinus thrombosis. AB - It is well established that in acute lymphoblastic leukemia (ALL) patients L asparaginase (L-Ase) provokes thrombotic events reducing coagulation inhibitors in both adults and children. A tight correlation between thrombotic and hemorrhagic complications and ALL has also been hypothesized because of the high incidence of disseminated intravascular coagulation (DIC) found during the early period of chemotherapeutic treatment apart from L-Ase. All the authors reporting on this subject, however, consider the remission induction phase of treatment the most risky, if not exclusive, for the development of a thrombotic event, in particular if it includes the administration of L-Ase. We report here two cases of ALL patients who experienced a cerebral sinus thrombosis in a later phase of treatment, demonstrating that the thrombotic risk is surely exacerbated by chemotherapy but is not exclusive to the remission induction period. PMID- 9368482 TI - Pseudomonas aeruginosa blepharoconjunctivitis during cytoreductive chemotherapy in a woman with acute lymphocytic leukemia. AB - Patients undergoing chemotherapy regimens for hematologic malignancies are prone to develop unusual and potentially life-threatening infections during periods of leukopenia- induced immunosuppression. We report the case of a woman who received consolidation chemotherapy for acute lymphocytic leukemia and acquired necrotizing Pseudomonas aeruginosa blepharoconjunctivitis of the right eye during a period of mild leukopenia. The infection led to severe orbital and periorbital inflammation, spreading down to the neck. High-dose antibiotic treatment with ceftazidime and tobramycin combined with granulocyte cell-stimulating factor cleared the infection after several days, but plastic surgery was needed to restore normal eye closure. PMID- 9368483 TI - Cerebellar myeloblastoma formation in CD7-positive, neural cell adhesion molecule (CD56)-positive acute myelogenous leukemia (M1). AB - We present a first report of a CD7+ acute myelogenous leukemia patient who developed intracranial myeloblastomas. The patient was neurologically normal on physical examination at presentation. The peripheral leukocyte count was extremely high (203.6 x 10(9)/l). The blasts expressed CD7 and CD56 (neural cell adhesion molecule) in addition to CD13, CD33, CD34, and HLA-DR. The karyotype of bone marrow cells was normal. The patient was diagnosed as having acute myelogenous leukemia (AML, M1). Following a short period of complete remission, bone marrow relapse and meningeal leukemia occurred, and the patient died of respiratory failure. Autopsy revealed that blasts had invaded the subarachnoid space and cerebellum, and two myeloblastomas were found in the cerebellar hemisphere. Both CD7+ and CD56+ AML have been reported to have a high incidence of central nervous system involvement. CD7+ CD56+ AML calls for prophylaxis of central nervous system leukemia. PMID- 9368484 TI - Myelofibrosis and idiopathic thrombocytopenic purpura. AB - A case of idiopathic myelofibrosis (IMF) with concomitant autoimmune thrombocytopenic purpura (AITP) is reported. The literature on platelet antibodies in IMF is reviewed. PMID- 9368485 TI - Reliability of automatic and visual analysis of interictal spikes in lateralising an epileptic focus during video-EEG monitoring. AB - We evaluated 2 h of two night recordings of surface EEG of 10 patients with drug resistant focal epilepsy using video-EEG monitoring, giving 40 h of EEG. The raw data of the automatic spike analysis according to the Gotman algorithm was visually corrected by rejecting false detections. Furthermore, the complete EEG recordings were analysed independently visually by two experienced electroencephalographers. For each method we analysed the total count of detections and the topographical distribution (left-right) of spikes. The total number of detections was significantly higher (243%) in the raw data and significantly lower after elimination of false detections (57%) in comparison to conventional analysis (100%). Lateralisation was concordant between the methods in 9/10 patients. The extent (< 75%, 75-90%, > or = 90%) was concordant in 80% between the two human raters. The automatic analysis with elimination of false detections was concordant with each of the human raters in 60% of patients. Extent of concordance was dependent of the total number of spikes with patients having more spikes being more reliably lateralised. Our results suggest that visually corrected automatic spike analysis is an economical method to use interictal epileptogenic activity as an independent indicator of the side of the epileptogenic focus in the setting of non-invasive presurgical evaluation. This is especially true in patients with many spikes. PMID- 9368486 TI - Mutual information analysis and detection of interictal morphological differences in interictal epileptiform discharges of patients with partial epilepsies. AB - The purpose of this paper is to compare the morphological features of interictal epileptiform discharges (IED) in patients with benign epilepsy of childhood with centrotemporal spikes to IED of those with symptomatic localization related epilepsies using information theory. Three patients from each clinical group were selected. Two-second epochs centered at the peak negativity of the sharp waves were analyzed from a referential montage during stage I sleep. The epochs from the two groups were compared using parametric and information theory analysis. Information analysis determined the likelihood of correctly identifying the clinical group based on the IED. Standard parametric, morphological and spectral analyses were also performed. We found no significant difference in the morphology of the sharp wave between the two groups. The after-going slow wave contained the greatest information that separated the two groups. This result was supported by morphological and spectral differences in the after-going slow wave. Greater distinguishing information is held in the after-going slow wave than the sharp wave for the identification of clinical groups. Information analysis may assist in differentiating clinical syndromes from EEG signals. PMID- 9368487 TI - Searching for hidden information with Gabor Transform in generalized tonic-clonic seizures. AB - The analysis of generalized tonic clonic seizures is usually difficult with scalp EEG due to muscle artifact. We applied Gabor Transform to evaluate 20 seizures from 8 consecutive patients admitted for video-EEG monitoring. We studied the relative intensity ratios of alpha, theta and delta bands over time. In 14/20 events we found a significant decremental activity in the delta band at the onset of the seizure indicating that this is dominated by theta and alpha bands. We conclude that GT is a useful auxiliary tool in the analysis of ictal activity that sheds light on the underlying pathophysiological mechanisms. PMID- 9368488 TI - Jerk-locked back averaging and dipole source localization of magnetoencephalographic transients in a patient with epilepsia partialis continua. AB - In order to localize the generator site of epileptiform discharges, we applied the techniques of jerk-locked back averaging (JBA) of magnetoencephalographic (MEG) activities and dipole source localization in a patient with epilepsia partialis continua (EPC), who showed continuous, focal myoclonic jerks in the right arm. The myoclonic discharges in the right thenar muscle were used as a trigger pulse. JBA revealed consistent EEG and MEG transients that coincided consistently and constantly preceded the myoclonic jerks. The estimated dipoles of MEG were localized in a restricted area in the left precentral area, which closely correlated with the area of epileptic discharges recorded in electrocorticography. Therefore, JBA of MEG is considered to be a useful non invasive method for localizing the epileptogenic area in EPC. PMID- 9368489 TI - A practical analysis of computer based seizure detection during continuous video EEG monitoring. AB - Computer based seizure detection (CSD) systems improve the efficiency of CCTV-EEG monitoring by capturing epileptic seizures which would have otherwise been missed. We prospectively evaluated the yield of a commercial CSD system in 83 consecutive CCTV-EEG admissions. All seizures were coded as to the method of detection. The percentage of seizures detected only by CSD was calculated for each patient and the impact on length of hospital stay was estimated. Overall, 33% of epileptic seizures were signaled by the patient, 45% were directly observed by family or medical personnel, and 22% were captured only by CSD. Forty admissions (48%) had at least one seizure captured only by CSD. The majority of these events were clinical and electrographic seizures (73%) and the remainder were purely electrographic. Five admissions concluded with all seizures captured only by CSD. We estimated an average saving of 1.3 hospital days per admission, based on the percentage of seizures captured only by CSD. PMID- 9368490 TI - Beyond habituation: long-term repetition effects on visual event-related potentials in epileptic patients. AB - Sixteen patients with partial epilepsy learned to produce positive or negative slow cortical potential shifts in a biofeedback condition during 20 consecutive training sessions. Visual ERPs to the presentation of the feedback and the discriminative stimulus were recorded at vertex. Regardless of the subjects' task (positivity versus negativity), amplitudes of the P2 (mean peak latency about 225 ms) and P3a (322 ms) components decreased across sessions, resulting in appearance and subsequent enhancement of a negative wave N2 (298 ms) between P2 and P3a. As N2 grew the P2 latency decreased and the P3a latency increased. Additionally, the P3b (472 ms) decreased with repetition, however, it did so slower than P2 and P3a. A comparison between the present data, on the one hand, and those obtained in the ERP habituation paradigm within one session, on the other hand, indicates that some repetition effects cannot be explained by habituation. PMID- 9368491 TI - Do chronic alcoholics have intact implicit memory? An ERP study. AB - In order to investigate whether visual object priming differs from visual word priming and whether the visual repetition priming in chronic alcoholic patients is impaired, we performed an ERP study on 27 male control and 67 male alcoholic subjects. Sixty-one electrodes were employed to record ERPs that were elicited by random presentations of object pictures, words, and scrambles for both pictures and words. We also used an implicit task that required subjects to identify whether each stimulus was recognizable. The current experiment revealed that (1) the reaction times to both recognizable picture and word stimuli were significantly shortened by the prior exposures of the same stimuli, (2) control subjects reflected visual object and word priming in different ERP components with different topographic patterns, (3) alcoholic subjects manifested visual word priming in the same ERP component as controls, and (4) the differences in ERP components, both in amplitude and topographic distribution, between the two groups occurred mainly in the different stimuli. These data suggest that the visual object and word priming have distinctive neural processes. The visual object priming in alcoholic subjects may be impaired while the visual word priming seemed to be intact. PMID- 9368492 TI - Genesis of MEG signals in a mammalian CNS structure. AB - Neuromagnetic signals of guinea pig hippocampal slices were characterized and compared with the extracellular field potential to elucidate the genesis of magnetoencephalographic signals in a mammalian CNS structure. The spatial distribution of magnetic evoked field (MEF) directed normal to bath surface was similar for transverse CA1, longitudinal CA1 and longitudinal CA3 slices in the presence of 0.1 mM picrotoxin (PTX) which blocks inhibitory synaptic transmission. Their MEFs were produced by currents along the longitudinal axis of the pyramidal cells. Comparisons of the MEF with the laminar potential profile revealed that the MEF was generated by intracellular longitudinal currents. The dipolar component of the intracellular currents was the dominant factor generating the MEF even at a distance of 2 mm from the slice. The MEF from a slice in Ringer's solution without PTX became similar in temporal waveform with time to the MEF in the presence of PTX, indicating the predominance of excitatory connections in generating the MEF and the existence of highly synchronous populations activities across the slice even in PTX-free Ringer's solution. The presence of such highly synchronous population activities underlying the MEFs was verified directly with field potentials recorded across the slice. A systematic variation of the stimulation site revealed a characteristic waveform for each site. The variation of the with stimulation site suggested the contribution of many factors, both synaptic and voltage-sensitive conductances, to the overall waveform of the MEF. PMID- 9368493 TI - A high resolution EEG method based on the correction of the surface Laplacian estimate for the subject's variable scalp thickness. AB - To improve the spatial resolution of human event-related potentials, we developed a new high resolution EEG method based on the improved estimate of the realistic surface Laplacian (SL). The novelty of this method consisted in the computation of the local scalp resistance that was assumed to be inversely proportional to the local scalp thickness measured from magnetic resonance images of the subject's head. The local scalp thickness was then multiplied by the SL estimate of the potential over a realistic magnetic resonance-constructed model of the subject's scalp surface. The new method was applied on human movement-related and somatosensory-evoked potentials, the SL estimate at a constant scalp thickness being used as a reference. The locally-predicted scalp thickness was significantly (P < 0.05) higher in the temporal areas (9.5 +/- 2.6 mm) than in the parieto-occipital (6.6 +/- 1.3 mm) and frontal (4.8 +/- 1.1 mm) areas. Compared to the SL estimate at constant scalp thickness, the improved SL estimate enhanced the spatial detail of both movement-related and somatosensory-evoked potentials. PMID- 9368495 TI - Confinement of intracellular calcium signaling in secretory and steroidogenic cells. PMID- 9368494 TI - P300 and long-term physical exercise. AB - Electrophysiologic effects of physical exercise were investigated by comparing groups of individuals who engage in relatively low amounts of physical exercise (< 5 h/week) to subjects who engage in relatively high amounts of aerobic exercise (> 5 h/week). Event-related brain potentials (ERPs) were recorded using auditory and visual stimuli in separate oddball task conditions. P300 amplitude was affected by exercise frequency, such that increased amounts of exercise were associated with increased amplitude and somewhat more so for visual stimuli. No reliable exercise effects for P300 latency were observed, with little effect found for the other components. The findings suggest that a history of intensive physical exercise affects P300 amplitude. Theoretical mechanisms are discussed. PMID- 9368496 TI - Neuroendocrine and behavioral effects of antisense oligonucleotides. PMID- 9368497 TI - Iodine and the brain: evidence from the mountains of Thailand. PMID- 9368498 TI - Cholinergic function and neural control of GH secretion. A critical re-appraisal. PMID- 9368499 TI - Estrogens and atherosclerosis: a direct protective effect on the vascular wall? PMID- 9368500 TI - Osteoprotegerin: a novel local player in bone metabolism. PMID- 9368501 TI - Endemic cretinism in Thailand: a multidisciplinary survey. AB - Endemic cretinism has been classified into neurological and myxedematous types. Profound mental deficiency, deaf-mutism and cerebral diplegia are predominantly found in the former. The latter have been described as less mentally retarded but with severe growth retardation and myxedematous features. The pathogenesis of different clinical types of endemic cretinism is still unclear. Recently, a unifying hypothesis suggested that iodine deficiency, severe enough to cause maternal and fetal hypothyroxinemia, results in neurological defects in all cretins. We conducted the present study in northern Thailand to determine the validity of this hypothesis in another geographical area. The study consisted of a multidisciplinary survey on 112 endemic cretins aged 2-66 years in Nan. They were categorized clinically into three types of endemic cretins, neurological (n = 57), myxedematous (n = 19) and mixed form (n = 36). The subjects were generally short and the majority had severe mental retardation (mean intellectual quotient (I.Q.) 30.8 +/- 8.8), psychomotor defect and profound sensorineural hearing loss. The I.Q. score and proportion of cretins with sensorineural hearing loss and psychomotor defect were similar among the three types of cretins. The most frequent neurological abnormalities were spasticity, hyper-reflexia, the presence of primitive reflexes and gait disturbance. These abnormalities were distributed equally among the three types of endemic cretins. Delayed skeletal maturation and abnormal epiphysis were also present in all types of cretins. However, myxedematous cretins were shorter (P < 0.01), having more myxedematous features (P < 0.05 to P < 0.001) and less sexual maturation (P < 0.05). Thyroid volume was lower in cretins with hypothyroidism (P < 0.01). In conclusion, our findings support the hypothesis that neurological features are present in all types of cretins, and are the consequence of maternal and fetal hypothyroxinemia due to severe iodine deficiency. The clinical manifestations of the cretins were subsequently modified by the length and severity of postnatal iodine deficiency and hypothyroidism. PMID- 9368502 TI - Effects of immigration on the incidence of congenital hypothyroidism. AB - OBJECTIVE: The incidence of congenital hypothyroidism (CH) has been shown to vary among different parts of the world. This could result from environmental or hereditary factors. Studies of other congenital diseases have shown that immigrants tend to retain the incidence of their country of origin while their children acquire the incidence of their new homeland, suggesting an environmental influence. This study aimed to assess the differences in the incidence of CH among immigrants from different parts of the world and to study the effects of immigration on its occurrence. METHODS: During the 9-year period between 1979 and 1987, 196 Jewish infants with primary CH were born in Israel; this constitutes an incidence of 1:3354 live births. We collected data from hospitals, endocrine pediatric clinics and the children's parents regarding the birth place of the parents and grandparents of those infants. These data were compared with the birth place of the parents and grandparents of all infants born in Israel during that period in order to learn about the incidence of CH among infants of different origins and to compare the incidence between children of parents born in Israel and those of immigrants of the same grandparental origin. RESULTS: CH incidence was lower among offspring of mothers and fathers of Israeli origin (1:4717 and 1:4255 live births respectively) and higher among those of African mothers (1:2950) and Asian fathers (1:2941). Parents of Asian or African origin, born in Israel have a lower incidence of CH-affected children compared with parents of the same origin born in their own continent. This trend is reversed for European and American parents, for whom being born in Israel is related to an increase in the CH incidence in their children. The difference in CH incidence between offspring of parents born in Israel and those of parents born in their original country was statistically significant (P < 0.05). In the different origin groups the gender of the parent did not influence significantly the incidence of CH. CONCLUSIONS: Environmental changes resulting from immigration can influence the incidence of congenital hypothyroidism. PMID- 9368503 TI - Clinical and genetic analysis of an inherited case of thyroid adenoma/cancer. AB - We studied a family in which thyroid neoplasms appeared to occur through genetic inheritance. Six blood relations, including the two probands, had thyroid carcinoma, and six others had benign thyroid tumors. When both parents had a thyroid neoplasm, their children frequently had thyroid neoplasms; this was confirmed through two generations of this family. To clarify the mechanism of inheritance, we performed chromosomal analysis, Southern blot analysis of three variable number of tandem repeats markers and HLA typing on two probands, and examined their RET proto-oncogenes, and p53 and RB tumor suppressor genes. We could not find any positive data on genetic analysis, although our data were limited. In conclusion, we studied a family in which thyroid neoplasms have occurred partly through genetic inheritance, although environmental factors may have influenced the occurrence of thyroid diseases. A search for a predisposing gene, using the microsatellite technique, is required to clarify the gentic factors involved. PMID- 9368504 TI - Serum TSH and the response to radioiodine treatment of toxic multinodular goitre. AB - A retrospective analysis of data from 73 consecutive patients with toxic multinodular goitre treated with iodine-131 (131I) during a 2-year period was performed to investigate if serum TSH at the time of 131I treatment influences the outcome. The dose of 131I was calculated according to a model compensating for thyroid size estimated by palpation and 24-h 131I uptake. Serum TSH was determined by a third-generation assay with a functional sensitivity of 0.03 mU/l. A significantly more pronounced response to 131I treatment was observed in patients with TSH > 0.0 mU/l than in patients with TSH = 0.0 mU/l (P = 0.0006. This difference resulted in a threefold lower frequency of non-responders and a fivefold higher rate of early hypothyroidism in the group with detectable serum TSH. While the high frequency of hypothyroidism among patients with measurable serum TSH can be explained by destruction of normal thyroid tissue, the high frequency of treatment failure in the group with serum TSH = 0.0 mU/l suggests that autonomous thyroid tissue may also be sensitized to a deleterious effect of 131I through stimulation by TSH. We conclude that serum TSH has a significant influence on the outcome of 131I treatment of toxic multinodular goitre. The results of 131I treatment may be improved by adjustment of the dose of 131I according to the serum TSH level, in addition to adjustment for goitre size and 24-h 131I uptake. PMID- 9368505 TI - Identification and characterization of a novel de novo mutation (L346V) in the thyroid hormone receptor beta gene in a family with generalized thyroid hormone resistance. AB - We have investigated an Italian family with generalized resistance to thyroid hormone (RTH), consisting of two individuals with elevated serum thyroid hormones (TH) and a non-suppressed TSH, together with unaffected family members, for a mutation in the thyroid hormone receptor beta gene (hTR beta). We have identified a single nucleotide substitution (1321 CTT to GTT) corresponding to a leucine to valine substitution at codon 346 (L346V) in the predicted protein. The index case and her affected child are heterozygous for the receptor defect, with normal sequence in unaffected family members. Furthermore, both parents of the index case were unaffected, suggesting that the mutation had arisen de novo. When expressed in vitro, the L346V mutant receptor showed a marked reduction in its affinity for tri-iodothyronine (T3), impaired ligand-dependent transactivation and potent dominant negative activity. Its functional impairment could not be alleviated, even at supraphysiological concentrations of T3, suggesting that the mutation might interfere with the intrinsic ligand-dependent transactivation function (AF-2) located in the hormone binding domain of hTR beta. Finally, the presence of the L346V mutation in the son of the propositus, who died from complications associated with congenital heart disease, raises the possibility that RTH might have contributed to the pathogenesis or severity of the latter. PMID- 9368506 TI - Pyridostigmine treatment selectively amplifies the mass of GH secreted per burst without altering GH burst frequency, half-life, basal GH secretion or the orderliness of GH release. AB - Growth hormone (GH) release from the anterior pituitary gland is predominantly regulated by the two antagonistic hypothalamic peptides, growth hormone-releasing hormone (GHRH) and somatostatin. Appraising endogenous GHRH action is thus made difficult by the confounding effects of (variable) hypothalamic somatostatin inhibitory tone. Accordingly, to evaluate endogenous GHRH actions, we used a clinical model of presumptively acute endogenous somatostatin withdrawal with concomitant GHRH release. To this end, we administered in randomized order placebo or the indirect cholinergic agonist, pyridostigmine, for 48 h to 13 healthy men of varying ages (29-77 years) and body mass indices (21-47 kg/m2). We sampled blood at 10-min intervals for 48 h during both placebo and pyridostigmine (60 mg orally every 6 h) administration, and used an ultrasensitive GH chemiluminescence assay (sensitivity 0.0002-0.005 microgram/l) to capture GH pulse profiles. Multiparameter deconvolution analysis was applied to quantitate the number, amplitude, mass, and duration of significant underlying GH secretory bursts, and simultaneously estimate the GH half-life and concurrent basal GH secretion. Approximate entropy was utilized as a novel regularity statistic to quantify the relative orderliness of the hormone release process. All measures of GH secretion/half-life and orderliness were statistically invariant across the two consecutive 24-h placebo sessions. In contrast, pyridostigmine treatment significantly increased the mean serum GH concentration from 0.23 +/- 0.054 microgram/l during placebo to 0.45 +/- 0.072 microgram/l during the first day of treatment (P < 0.01). There was also a significant rise in the calculated 24-h pulsatile GH production rate from 8.9 +/- 1.7 micrograms/l/day on placebo to 27 +/- 5.6 micrograms/l/day during active drug treatment (P < 0.01). Pyridostigmine significantly and selectively amplified GH secretory burst mass to 1.5 +/- 0.35 micrograms/l compared with 0.74 +/- 0.19 microgram/l on placebo (P < 0.01). This was attributable to stimulation of GH secretory burst amplitude (maximal rate of GH secretion attained within the release episode) with no prolongation of estimated burst duration. Basal GH secretion and approximate entropy were not altered by pyridostigmine. However, age was strongly related to more disorderly GH release during both days of pyridostigmine treatment (r = +0.79, P = 0.0013). During the second 24-h of continued pyridostigmine treatment, most GH secretory parameters decreased by 15-50%, but in several instances remained significantly elevated above placebo. Body mass index, but not age, was a significantly negative correlate of the pyridostigmine-stimulated increase in GH secretion (r = -0.65, P = 0.017). In summary, assuming that somatostatin is withdrawn and (rebound) GHRH release is stimulated via pyridostigmine administration, we infer that relatively unopposed GHRH action principally controls GH secretory burst mass and amplitude, rather than apparent GH secretory pulse duration, the basal GH secretion rate, or the serial regularity/orderliness of the GH release process in the human. Moreover, we infer that increasing age is accompanied by greater disorderliness of somatostatin-withdrawn GHRH, and hence rebound GH, release. The strongly negative correlation between pyridostigmine-stimulated GH secretion and body mass index (but not age) further indicates that increased relative adiposity may result in decreased effective (somatostatin-withdrawn) endogenous GHRH stimulus strength. PMID- 9368507 TI - Serum leptin in short children born small for gestational age: relationship with the growth response to growth hormone treatment. The Swedish Study Group for Growth Hormone Treatment. AB - The product of the obese (ob) gene, leptin, is an adipocyte-derived hormone that is involved in the regulation of appetite and body weight. This study was undertaken in order to describe the basal serum levels of leptin in prepubertal short children born small for gestational age (SGA) and their relationship with growth parameters, before and during growth hormone (GH) treatment. Eighty-nine prepubertal short children (66 boys, 23 girls; height standard deviation score (SDS), -5.4 to -2.0; age, 2.0 to 12.8 years) born SGA, 12 of whom (9 boys, 3 girls) had signs of Silver-Russell syndrome, were included in the study. Serum leptin concentrations were measured by radioimmunoassay. Leptin levels in the children born SGA were compared with those in a reference group of 109 prepubertal healthy children born at an appropriate size for gestational age (AGA). The mean (S.D.) change in height SDS was 0.11 (0.22) during the year before the start of GH therapy (0.1 IU/kg/day) and increased to 0.82 (0.44) during the first year (P < 0.001) and to 1.28 (0.59) during the 2-year period of GH therapy (P < 0.001). The children born SGA were significantly leaner than the reference group. An inverse correlation was found between leptin and chronological age in the SGA group (r = -0.31, P < 0.01). The mean serum level of leptin in the children born SGA who were older than 5.5 years of age was 2.8 micrograms/l which was significantly lower than the mean value of 3.7 micrograms/l found in the children born AGA of the same age range. The difference remained after adjustment of leptin levels for sex, age, body mass index (BMI) and weight-for-height SDS (WHSDSSDS). Leptin correlated with WHSDSSDS (r = 0.32, P < 0.001) and BMI (r = 0.36, P < 0.01) in the reference population, but not in the SGA group. No correlation was found between leptin and spontaneous 24-h GH secretion, insulin-like growth factor (IGF)-I or IGF-binding protein-3 levels, or with fasting insulin or cortisol levels. Leptin levels at the start of GH treatment were correlated with the growth response over both 1 year (r = 0.46, P < 0.001) and 2 years (r = 0.51, P < 0.001) of GH therapy. Using multiple regression analysis, models including leptin levels at the start of GH therapy could explain 51% of the variance in the growth response after 1 year and 44% after 2 years of GH treatment. In conclusion, serum leptin levels are reduced in short children born SGA and are inversely correlated with chronological age. Leptin concentrations correlate with the growth response to GH treatment and might be used as a marker for predicting the growth response to GH treatment. PMID- 9368508 TI - High molecular weight forms of IGF-II ('big-IGF-II') released by Wilms' tumor cells. AB - Insulin-like growth factor-II (IGF-II) is thought to play a critical role in the development of embryonic tumors such as Wilms' tumor. However, despite highly elevated IGF-II mRNA levels in tumors, IGF-II is not elevated in the serum of patients with Wilms' tumors. Recently high molecular weight forms of IGF-II ('big'- or pro-IGF-II) have been found to be produced by some tumors. In order to prove whether or not high molecular weight forms of IGF-II are produced by Wilms' tumor cells and secreted into the culture medium, we established Wilms' tumor cell lines. After column chromatography of the culture medium, IGF-II and pro-IGF II concentrations were measured. For pro-IGF-II measurement we established a pro IGF-II RIA using a rabbit polyclonal antiserum directed against amino acids 7-21 (E7-21) of the E-domain of pro-IGF-II. Gel electrophoresis and Western blotting with anti-IGF-II antibodies revealed a band at 7.5 kDa corresponding to fully processed IGF-II and bands between 10 and 20 kDa. Using pro-IGF-II antiserum, bands between 10 and 25 kDa were detected. We conclude that in vitro cultured Wilms' tumor cells produce and release various forms of 'big IGF-II' with molecular masses between 10 and 25 kDa. It remains uncertain whether these high molecular weight forms of IGF-II represent normal precursors of IGF-II or incorrectly processed IGF-II. PMID- 9368509 TI - Calcium-regulating hormones and parathyroid hormone-related peptide in normal human pregnancy and postpartum: a longitudinal study. AB - OBJECTIVES: To evaluate calcium-regulating hormones and parathyroid hormone related peptide (PTHrP) in normal human pregnancy and postpartum in women not deficient in vitamin D. DESIGN: A prospective longitudinal study was conducted in pregnant Saudi women during the course of pregnancy (n = 40), at term and 6 weeks postpartum (n = 18). Maternal concentrations of serum calcidiol and calcitriol were determined, together with those of serum intact-parathyroid hormone (PTH), PTHrP, calcitonin, osteocalcin, human placental lactogen (hPL), prolactin, vitamin D binding protein, alkaline phosphatase, calcium, phosphate and magnesium. A group of non-pregnant women (n = 280) were included for comparative purposes. RESULTS: The calcidiol concentrations decreased (mean +/- S.D.) significantly from 54 +/- 10 nmol/l in the first trimester to 33 +/- 8 nmol/l in the third trimester (P < 0.001) and remained decreased at term and postpartum (both P < 0.001). The calcitriol concentration increased through pregnancy, from 69 +/- 17 pmol/l in the first trimester to 333 +/- 83 pmol/l at term (P < 0.001). Intact-PTH concentrations increased from 1.31 +/- 0.25 pmol/l in the first trimester to 2.26 +/- 0.39 pmol/l in the second trimester, but then declined to values of the first trimester and increased significantly postpartum (4.02 +/- 0.36 pmol/l) (P < 0.001). PTHrP concentration increased through pregnancy from 0.81 +/- 0.12 pmol/l in the first trimester to 2.01 +/- 0.22 pmol/l at term and continued its increase postpartum (2.63 +/- 0.15 pmol/l) (P < 0.001). Significant positive correlations were evident between PTHrP and alkaline phosphatase up to term (r = 0.051, P < 0.001) and between PTHrP and calcitriol (r = 0.46, P < 0.001), osteocalcin (r = 0.23, P < 0.05) and prolactin (r = 0.41, P < 0.05) during pregnancy. Osteocalcin started to increase from 0.13 +/- 0.01 nmol/l in the second trimester, through pregnancy and postpartum (P < 0.001). Calcitonin was increased more than twofold by the second trimester compared with the first trimester (P < 0.001) and subsequently decreased (P < 0.001). Prolactin concentrations were significantly greater in the second (6724 +/- 1459 pmol/l) and third (8394 +/- 2086 pmol/l) trimesters compared with values before pregnancy (P < 0.001). hPL, increased throughout the course of pregnancy, reaching a maximum at term (7.61 +/- 2.57 microIU/ml). There was no direct correlation between serum calcitriol concentrations during pregnancy and serum prolactin (r = -0.12, P < 0.19) or serum hPL (r = 0.17, P < 0.21). Significant changes were observed in the serum concentrations of calcium and phosphate, but not in that of magnesium, during the course of pregnancy; calcium concentrations showed a maximal decrease at term. CONCLUSIONS: Changes in serum PTHrP during the course of pregnancy, at term and postpartum have been demonstrated, suggesting that the placenta (during pregnancy) and mammary glands (postpartum) are the main sources of PTHrP. No support for the concept of 'physiological hyperparathyroidism' of pregnancy could be demonstrated in the present work. The pregnancy-induced increase in calcitriol concentration may thus be the primary mediator of the changes in maternal calcium metabolism, but the involvement of other factors cannot be excluded. PMID- 9368510 TI - Retinoic acid receptors alpha, beta and gamma, and cellular retinol binding protein-I expression in breast fibrocystic disease and cancer. AB - Retinoids seem to act as agents of chemoprevention and differentiation in breast diseases. Their action is mediated by nuclear receptors, retinoic acid receptors (RAR alpha, RAR beta, RAR gamma) and retinoid X receptors (RXR alpha, RXR beta, RXR gamma) and modulated by cellular retinol binding proteins (CRBP). There are few published data on CRBP expression. In this study, we evaluated the expression of RAR alpha, beta and gamma and CRBP type I (CRBP-I) gene expression in fibrocystic disease (FD) and in breast cancer (BC), studying 14 FD and 20 BC surgical samples by reverse transcription (RT)-PCR. We also evaluated mRNA concentrations in cancer samples by a semiquantitative PCR method, co-amplifying RAR alpha, RAR beta and CRBP-I genes with an unrelated gene, glyceraldehyde 3 phosphate dehydrogenase (GAPDH), as internal control. All benign and malignant breat tissues expressed RAR alpha, beta and gamma, and CRBP-I mRNAs. A greater concentration of RAR beta mRNA was detected in cancer tissues with lower oestrogen and progesterone receptor concentrations, whereas RAR alpha was detected in variable concentrations that were not related to those of steroid receptors. The CRBP-I concentration was similar in all samples studied. We demonstrated that all three RARs and CRBP-I transcripts are expressed in FD, and that RAR beta, RAR gamma and CRBP-I mRNAs also are present in BC tissues. This indicates that both malignant and benign breast tissues may be target for retinoids, justifying the use of natural and synthetic vitamin A derivatives in the chemoprevention of breast disease. PMID- 9368511 TI - Modulation of T3-induced sex hormone-binding globulin secretion by human hepatoblastoma cells. AB - We have shown previously that tri-iodothyronine (T3)-induced sex hormone-binding globulin (SHBG) secretion by the human hepatoblastoma cell line, HepG2, can be modulated by retinoids. We have now used this model to study a range of other compounds that are known to influence T3 responsiveness in various cell systems. HepG2 cells were incubated for 4 days in serum-free medium containing T3, together with insulin, dexamethasone, phorbol myristate (PMA), sodium butyrate or estradiol. T3 (10 nmol/l) alone induced a concentration of SHBG secreted by HepG2 cells that was 187 +/- 20% (mean +/- S.D., n = 9) of control. Insulin (100 nmol/l) reduced basal SHBG secretion from 24.7 +/- 5.2 nmol/l to 16.1 +/- 1.7 nmol/l (P < 0.01). This effect was dose responsive, half-maximal at 3.4 +/- 3.0 nmol/l (approximately 600 mU/l) and maximal with 100 nmol/l insulin. Co incubating 0-10 nmol/l T3 with 100 nmol/l insulin resulted in a downward shift in the dose-response curve without a change in the half-maximal response to T3. Conversely, 0-100 nmol/l insulin reduced SHBG production induced by 10 nmol/l T3. In contrast; while dexamethasone alone was without effect on SHBG secretion, 100 nmol/l dexamethasone induced a shift to the left in half-maximal T3 stimulation from 0.37 nmol/l to 0.10 nmol/l. The effect of PMA on SHBG secretion was reminiscent of the previously observed retinoid effect. PMA 100 nmol/l abolished maximal T3 stimulation. This effect was dose responsive, with a threshold at 1 nmol/l PMA. Sodium butyrate, up to 1 mmol/l was without effect; with greater concentrations, SHBG secretion was reduced. T3 responsiveness was virtually abolished by 3 mmol/l sodium butyrate; higher concentrations were cytotoxic and secretion was reduced to less than 20% of basal. Lack of an effect of estradiol on SHBG secretion by HepG2 cells was confirmed. These studies suggest that T3 induced SHBG secretion by HepG2 cells is independently influenced by insulin, potentiated by dexamethasone, and modulated by PMA. Detailed molecular analysis of this model will increase our understanding of the mechanism of action of T3, specifically in human liver cells. PMID- 9368512 TI - Plasma bovine pregnancy-associated glycoprotein concentrations throughout gestation in relationship to fetal number in the cow. AB - This study characterized the peripheral plasma bovine pregnancy-associated glycoprotein (bPAG) profile throughout gestation and examined the effect of stage of gestation and fetal number on this profile in Holstein cows after non-surgical embryo transfer. Cows (n = 12) were divided into three groups: group 1 = normal singleton pregnancies (n = 5); group 2 = normal twin pregnancies (n = 5); group 3 = abnormal twin pregnancies (n = 2). Blood was collected about every third day from day 0 (defined as the first day of standing estrus), then daily for the last 10 days of gestation, and sampling was stopped one day postpartum. The time related changes in plasma bPAG concentrations were significantly (P < 0.01) affected by the stage of gestation and fetal number (P < 0.01), except during the last 10 days of gestation. In both normal pregnancy groups, bPAG concentration increased rapidly during the first trimester (0.5 +/- 0.1 to 14.6 +/- 1.7 ng/ml and 1.0 +/- 0.6 to 21.8 +/- 4.8 ng/ml, in singleton and twin-bearing groups respectively), then progressively between days 160 and 20 prepartum (31.6 +/- 6.2 to 114.3 +/- 31.3 ng/ml and 41.6 +/- 7.4 to 155.8 +/- 36.6 ng/ml in singleton and twin-bearing cows respectively). The mean concentration between days 20 and 10 prepartum approximately tripled (P < 0.001) in both these groups of cows (114.3 +/- 31.1 to 493.0 +/- 75.3 ng/ml and 155.8 +/- 36.6 to 409.3 +/- 114.7 ng/ml in singleton and twin-bearing cows respectively), but between days 10 prepartum and parturition the values increased about threefold (P < 0.01) in the singleton group (493.0 +/- 75.3 to 1352.8 +/- 286.5 ng/ml) and fivefold (P < 0.001) in the twin-bearing group (409.3 +/- 114.7 to 2154.0 +/- 505.7 ng/ml). The two cows in group 3 that gave birth prematurely to a stillborn calf or to a schistosomus reflexus calf exhibited an aberrant bPAG profile. Our results indicate that peripheral bPAG concentrations are correlated to the stage of gestation and fetal number, and that the profile of the peripheral plasma concentrations provides a useful indication of the feto-placental status. PMID- 9368513 TI - Effect of glucocorticoids and oestrogen on interleukin-6 production by human thyrocytes from patients with Graves' disease and toxic multinodular goitre and from HTori3 cells. AB - Interleukin-6 (IL-6) is a cytokine released by thyrocytes and is involved in disease processes such as autoimmune thyroid disease. The secretion of IL-6 can be stimulated by interleukin-1 (IL-1), tumour necrosis factor-alpha (TNF), serum, TSH and agents which increase intracellular cyclic AMP levels. Antithyroid drugs such as methimazole inhibit IL-6 production by thyrocytes but the effects of glucocorticoids and oestrogen have not been investigated. The effects of dexamethasone and 17 beta-oestradiol on IL-1-, TNF-, TSH-, forskolin- and phorbol 12-myristate 13-acetate (PMA)-stimulated IL-6 release in serum-free conditions were studied in human thyrocytes derived from patients with Graves' disease and toxic multinodular goitres, and in the immortalised human thyrocyte cell line, HTori3. Dexamethasone inhibited IL-6 production under stimulated conditions. In serum-free conditions, no basal release of IL-6 was assayable. In all but one of the primary thyroid cultures, TSH did not stimulate IL-6 release above the lower detectable limit of the assay. In Graves' and multinodular goitre thyrocytes, inhibition of IL-1 (100 U/ml)-stimulated IL-6 release by dexamethasone (100 nmol/l) was 62.51% +/- 10.43 (S.E.M.), and in HTori3 cells it was 78.35% +/- 3.9. The degree of IL-1 stimulation of IL-6 release and inhibition by dexamethasone was not significantly different in thyrocytes derived from either Graves' or multinodular glands. 17 beta-Oestradiol had no effect on IL-1-stimulated IL-6 release in either primary thyroid cell culture or in HTori3 cells. PMID- 9368514 TI - Competing causes of death: a death certificate study. AB - BACKGROUND: Despite the widespread interest in competing causes of death, empirical information on interrelationships between causes of death is scarce. We have used death certificate information to estimate the prevalence of competing causes of death at the moment of dying from specific underlying causes of death. MATERIALS AND METHODS: In a stratified sample of 5975 deaths occurring in The Netherlands in 1990, information contained in the death certificate was used to determine the presence of diseases which, in the hypothetical case of elimination of the underlying cause of death, could develop into a new underlying cause of death. Poisson regression analysis was used to describe variation in age- and sex adjusted prevalence of competing causes of death between different underlying causes. RESULTS: Per 100 deaths, 46.2 competing causes were identified (52.0 after reweighting to take away the effects of stratification). The most frequent competing causes, all occurring in more than 2% of deaths, were: senile dementia, diabetes mellitus, ischemic heart disease, cerebrovascular disease, chronic obstructive lung disease, hypertensive disease, and arteriosclerosis. The overall prevalence of competing causes is relatively high among deaths from respiratory diseases (relative risk for respiratory diseases as compared with all underlying causes (RR) = 1.42 (95% CI, 1.25-1.62)), relatively low among deaths from neoplasms (RR = 0.54 (95% CI, 0.47-0.62)), and in between among deaths from cardiovascular diseases (RR = 1.08 (95% CI, 0.95-1.22)). CONCLUSION: Although it cannot be excluded that some of the variation in prevalence of competing causes by underlying cause is due to selective underregistration of coexisting diseases on death certificates, the results of this study suggest that conventional estimates of gains in life expectancy after elimination of neoplasms are much less biased by the effect of competing causes than the corresponding estimates for cardiovascular diseases and particularly respiratory diseases. PMID- 9368515 TI - Optical illusions from visual data analysis: example of the New Zealand asthma mortality epidemic. AB - The abundance of health-related statistics routinely collected worldwide invites their misuse from haphazard associations between secular trends of these data. This misuse is often compounded by assessing these associations simply on the basis of a visual inspection of the data. The visual approach to data analysis, known to have several pitfalls, is particularly tempting in the context of asthma where it has often been used. For example, the epidemic of asthma deaths that occurred in New Zealand during the last two decades has been imputed to fenoterol, a medication for asthma, on the basis of a visual assessment of ecological data. The simultaneity of time trends in the asthma death rate and fenoterol market share in that country formed an important part of the statistical basis of the evidence. We verified whether the results of such visual analyses are corroborated by more objective quantitative statistical methods of analysis. We reanalyzed these same data, namely the time trend data of New Zealand asthma death rates, fenoterol market share, sales of beta-agonists and inhaled corticosteroids, measured yearly for the 16-year span 1976-1991, using Poisson weighted loglinear regression. We found that the protective effect of inhaled corticosteroids (rate ratio 0.5 per canister per month; 95% confidence interval 0.4 to 0.7; p = 0.0001) was more closely associated with changes in asthma mortality than either fenoterol (RR 2.7 per canister per month; 95% CI: 0.9 to 7.5; p = 0.06) or all beta-agonists combined (RR 1.6; 95% CI: 0.8 to 3.0; p = .19). We conclude from this quantitative analysis that these ecological asthma mortality data provide evidence of a stronger association with inhaled corticosteroids, little used in New Zealand at the onset of the epidemic but used abundantly at its termination, than with fenoterol. This conclusion is diametrically opposite to that found by the visual approach. The quantitative analysis demonstrates that the visual approach to the analysis of ecological data, although seemingly convincing, can be misleading by creating an optical illusion. This purely visual approach to data analysis may thus have serious implications when the resulting scientific information is used to make vital public health and policy decisions. PMID- 9368516 TI - The impact of high-risk patients on the results of clinical trials. AB - The results of clinical trials may not reflect equally the experiences of all their individual participants. By modeling populations where patients have very diverse baseline risks of suffering an event of interest, it can be seen that very sick patients of high risk become the major determinants of how many events occur in the whole population, even though they may represent only a small minority. Human immunodeficiency virus-related trials and trials of magnesium in acute myocardial infarction are analyzed. When the benefit or toxicity from a treatment varies with the baseline risk of each patient, the treatment effect may be markedly different in populations with a different representation of high- and low-risk patients. The results of small clinical trials studying heterogeneous populations with binary outcomes depend on the sampling and outcomes of very few high risk participants. Conversely, mega-trials studying homogeneous populations would miss subgroups or individuals with diverse treatment responses. In both cases, aggregate trial results may be misleading for the care of many individuals. PMID- 9368517 TI - Body weight, pre-existing disease, and all-cause mortality in a cohort of male employees in the German construction industry. AB - The impact of body weight on all-cause mortality is subject to ongoing debate. We assessed the relation between body mass index (BMI) and all-cause mortality in a cohort of 8043 male employees in the German construction industry who underwent detailed occupational health examinations at ages 25-64 and who were followed for all cause mortality over an average period of 4.5 years. Overall, there was a negative, graded relation between BMI and all-cause mortality, which persisted after controlling for multiple covariates including age and cigarette smoking, and after excluding the initial two years of follow-up. There was a strong positive cross-sectional relationship between BMI and a medical diagnosis of diabetes, hypertension, and ischemic heart disease at the baseline examination. While BMI showed a strong negative relation with all-cause mortality among men with such diseases, the association was much weaker and non-monotonic for mean free of these diseases. Our results underline the importance of preexisting diseases for the prognostic value of body weight. PMID- 9368518 TI - Self-rated health and mortality in Chinese institutional elderly persons. AB - The relationship between self-rated health (SRH) and subsequent mortality was examined in a cohort of 411 Chinese elderly individuals living in institutions. SRH was assessed by a global health rating, by comparing health with others of the same age, and by perception of recent physical condition. Covariates including age, sex, daily activity function, instrumental daily activity function, cognitive function, self-reported visual acuity, urinary function, number of chronic conditions, number of medications, and history of falls were controlled by the Cox proportional hazard model. Elderly people who rated their global health as "fair or poor" had increased mortality compared to those in the "good" category (RR = 6.00; 95% CI 1.39-25.1) and a borderline significant increase in mortality risk for those who rated themselves in the "average" category (RR = 4.05; 95% CI 0.93-17.70). Elderly people who compared their health with others of the same age as "worse or worst" and "similar" had an RR of 2.75; 95% CI of 0.64-11.83 and RR of 2.40; 95% CI of 0.64-8.96, respectively. Elderly people who rated their physical symptoms as "moderate or severe" and "slight" had an RR of 2.54; 95% CI 0.65-9.80 and RR of 1.05; 95% CI 0.32-3.41, respectively. Age, institutional factors, and history of multiple falls were associated with an increased risk of mortality. We concluded that only the global health rating has direct predictive power for mortality in institutionalized elderly people. PMID- 9368519 TI - Correlates and effect of non-response in a postpartum survey of obstetrical care quality. AB - This study investigated the differences between unprompted respondents, prompted respondents, and non-respondents to a postpartum postal survey, and determined the likely impact of non-response on the accuracy of calculations of patient assessments of obstetrical care quality. Birth certificate and hospital discharge data were obtained for 1664 live births at three hospitals in Washington State between 8/91-10/91 and linked with 1268 completed postpartum maternal postal surveys. Non-white race, public insurance payer, unmarried status, and smoking in pregnancy were independent risk factors for non-participation. Among participants, non-white race, unmarried status, and having an infant who was low birthweight, preterm, or discharged late were independent risk factors for prompted response. The inclusion of prompted respondents did not substantially alter the calculated proportion of women rating obstetrical care quality as low, and these figures were similar to proportions estimated for the entire intended cohort using a modification of Drane's method. A one-time mailing of an obstetrical care quality survey can provide information similar to that obtained with more extensive follow-up even though substantial differences may exist between unprompted and prompted respondents, and with adjustment for factors related to non-participation and timing of response, it may be possible to obtain accurate estimation of outcome prevalences for the entire intended cohort. PMID- 9368520 TI - Analysis of non-response bias in a mailed health survey. AB - The objective of this study was to identify characteristics of non-respondents and late respondents to a mailed health survey. Persons who returned and those who did not return the questionnaire were compared using health insurance data, which indicated their age, sex, and health care expenditures in the previous year. Insurance and questionnaire data were used to compare early and late survey respondents and to compare categories of non-respondents. Questions covered use of health services, health status, and sociodemographic characteristics. Participants were members of health insurance plans in Geneva, Switzerland, 19-45 years old (n = 1822). Respondents (n = 1424) and non-respondents (n = 398) were of similar age and sex. The proportion of persons who had health care expenditures greater than zero Swiss francs (SFr) was higher among respondents (75%) than among non-respondents (69%, p = 0.03). Among non-respondents, expenditures of persons who explicitly refused to participate (2378 SFr) were higher than expenditures of persons who moved out of Geneva (1085 SFr) or who failed to return the questionnaire (1592 SFr, p = .02). Among respondents, being born in a Switzerland, having completed elementary school, having generated health care expenditures, and reporting good physical health were independent predictors of early response. In conclusion, low response rates to mailed health surveys may result in overestimating the utilization of health services. However, non-respondents did not constitute a homogeneous group, and the strength and even direction of non-response bias depended on the mechanisms of non-response. PMID- 9368521 TI - Response rates to mail surveys published in medical journals. AB - OBJECTIVE: The purpose of this study was to characterize response rates for mail surveys published in medical journals; to determine how the response rate among subjects who are typical targets of mail surveys varies; and to evaluate the contribution of several techniques used by investigators to enhance response rates. METHODS: One hundred seventy-eight manuscripts published in 1991, representing 321 distinct mail surveys, were abstracted to determine response rates and survey techniques. In a follow-up mail survey, 113 authors of these manuscripts provided supplementary information. RESULTS: The mean response rate among mail surveys published in medical journals is approximately 60%. However, response rates vary according to subject studied and techniques used. Published surveys of physicians have a mean response rate of only 54%, and those of non physicians have a mean response rate of 68%. In addition, multivariable models suggest that written reminders provided with a copy of the instrument and telephone reminders are each associated with response rates about 13% higher than surveys that do not use these techniques. Other techniques, such as anonymity and financial incentives, are not associated with higher response rates. CONCLUSIONS: Although several mail survey techniques are associated with higher response rates, response rates to published mail surveys tend to be moderate. However, a survey's response rate is at best an indirect indication of the extent of non respondent bias. Investigators, journal editors, and readers should devote more attention to assessments of bias, and less to specific response rate thresholds. PMID- 9368522 TI - Changes in lipids associated with change in regular exercise in free-living men. AB - OBJECTIVE: To investigate the relationship between regular exercise and plasma lipid profiles in free-living men. METHODS: Seven hundred eighty men between the ages of 25 and 65 years were included in this study. The medical history, physical examination, and blood tests were obtained at baseline and 1 year later. At the end of the study, 430 (55.1%) men reported the same amount of regular exercise as a year earlier; 199 (25.5%) men reported an increased level, and 151 (19.4%) men reported a decreased level. RESULTS: Compared to the group with same exercise, men who increased their level of regular exercise had a significant increase in high-density lipoprotein cholesterol (HDLC) (mean 4.76 versus 2.83 mg/dL, p < 0.005) and significant decreases in the ratio of total cholesterol/HDLC (mean -0.72 versus -0.42, p < 0.001) and triglycerides (mean 18.2 versus -6.27 mg/dL, p < 0.001). The changes in lipid profiles appeared to have a dose-response relationship from the increased exercise, same exercise, to decreased exercise groups. Overweight and normal-weight men had a similar tendency to improve their lipid profiles by exercise. The improvement in plasma lipid profile associated with increased regular exercise persisted after controlling for potential confounders. CONCLUSIONS: The results indicate that the relationship between physical activity and favorable lipid profiles exists in men with mild-to-moderate physical activity. PMID- 9368523 TI - Estimating the size of a population from a single sample: methodology and practical issues. AB - In contrast to classical capture recapture methods, the single-sample method of Laska, Meisner, and Siegel (1988) (LMS) enables estimation of the size of a population, N*, on the basis of a single survey. For example, it may be desired to estimate the unduplicated number of individuals served by a mental health center during the last year on the basis of a 1-week sample. The time since each of the sampled individuals last engaged in the activity that defines the population is ascertained. The LMS estimator of N* and its unbiasedness property are motivated in a simple way, and an improved LMS estimator is introduced if additional information is available. An empirical assessment of the procedure is made using mental health service data for which the true population size is known. The performance of the extended LMS estimator is a substantial improvement over the standard LMS estimator. PMID- 9368524 TI - Statistical methods for describing temporal order in longitudinal research. AB - BACKGROUND: Although traditional epidemiological statistical methods (e.g., logistic regression) are useful for describing predictive relationships in longitudinal panel studies in which changes in risk factor levels occur before change in the outcome variable, more sophisticated statistical methods must be used when the temporal order between variables is unknown. METHODS: Using national survey data, the current study shows how log-linear models and discrete time survival analysis can be used to test for temporal order. The relationship between marijuana use and friends' use of marijuana is examined to illustrate these methods. RESULTS: Using traditional analytic strategies, it appears that friends use and marijuana use are predictive of each other. However, valid tests for temporal order reveal that both variables change concurrently, so there is no temporal order between these variables; rather, these variables tend to change concurrently. CONCLUSION: In many current areas of research, temporal order between theoretically important variables is unknown and traditional analytic strategies will yield misleading results. The fundamental problem with prior approaches is that no estimate of concurrent change is made. Without an estimate of concurrent change, estimates of prediction will be biased. The current study illustrates valid methods that can be used to describe temporal orderings. PMID- 9368525 TI - Quality control for blood pressure measurement in population studies: Shibata Children's Heart Study. AB - To investigate the relation between observer performance for blood pressure measurement in a training process and in field conditions, measurement values were studied under training and field conditions among 21 blood pressure observers of 1434 subjects aged 6-15 years in Japan. The observers received training by a videotape, which included six audiovisual presentations of a falling mercury column in a standard sphygmomanometer with Korotkoff sounds. Observer bias was measured for each trainee as the mean difference between the observed and the standard values for each blood pressure reading, including systolic (SBP), fourth-phase diastolic (K4), and fifth-phase diastolic (K5) values. In multiple linear regression analyses, each 1 mmHg increment in observer bias was equivalent to 1.27, 0.88, and 1.25 mmHg difference in actual readings of SBP, K4, and K5, respectively, in the field. This finding indicates that observer performance in videotape training is predictive of measurement behavior in the field. PMID- 9368526 TI - Low blood pressure associated with low mood: a red herring? AB - OBJECTIVE: Several reports have discussed a relationship between blood pressure (BP) and psychological well-being scales. Lower BP readings were associated with higher levels of psychological distress and fatigue. This study sought to replicate the association found by previous secondary analyses of epidemiological surveys. DESIGN: Cross-sectional study. SETTING: Academic Family Medicine Department in Toronto, Canada. SUBJECTS: 214 practice attenders. STUDY MEASURES: Extent of psychological abnormalities with the General Health Questionnaire (GHQ), self-reported fatigue, in-clinic and home BP measurements. RESULTS: No significant relationship between blood pressure levels and GHQ-score or fatigue could be demonstrated. This applies to clinic and home measurements for systolic and diastolic pressure. Neither adjustment for age or sex nor for several confounders through multiple linear regression produced significant associations in the postulated direction. No nonlinear relationship could be shown either. The study had a power of 95% to detect a correlation of r = 0.22 (alpha = 0.05, one sided). CONCLUSION: The study specifically addressing the possible link between blood pressure and psychological dysfunction/fatigue, could not confirm the previously reported association. Problems related to type-I error in epidemiological research are discussed. PMID- 9368527 TI - Throw that epidemiologist out of the emergency room! Using the television series ER as a vehicle for teaching methodologists about medical issues. AB - BACKGROUND: Epidemiology and biostatistics graduate students have diverse backgrounds, but many have little prior training in medicine or biology. This lack of content knowledge in future health researchers has recently been raised as a concern. METHODS: As part of a graduate course on the epidemiology of major diseases, the television series ER was used as a vehicle for learning more about diseases in general, and to become familiar with medical terminology and the ICD 10 by practicing coding on the patients seen. Furthermore, we wanted to provide human faces to the type of disease data students usually work with. RESULTS: In this article, the authors discuss how the ER sessions were organized and the problems that were encountered. The course evaluation concluded that the students found the exercise to be an interesting break from regular teaching. PMID- 9368528 TI - P. C. A. Louis and the birth of clinical epidemiology. PMID- 9368529 TI - Controversies in the management of childhood meningitis. PMID- 9368530 TI - Serratia marcescens. AB - Over the last 30 years, Serratia marcescens has become an important cause of nosocomial infection. There have been many reports concerning the identification, antibiotic susceptibility, pathogenicity, epidemiological investigations and typing of this organism. Accurate identification is important in defining outbreaks. The API 20E system has been used widely, but is not individually satisfactory. The growth of S. marcescens in the environment has been investigated in relation to water, disinfectants and plastics such as blood bags. Certain extracellular products are unique to S. marcescens. Pigment (prodigiosin) biosynthesis by S. marcescens has been investigated fully since the emergence of the organism as a cause of infection. Many other aspects of the pathogenicity and virulence of S. marcescens have been studied, including adherence and hydrophobicity, lipopolysaccharide (LPS) and extracellular products. Two modes of adhesion to host epithelial surfaces have been suggested. These are mannose resistant (MR) pili and mannose-sensitive (MS) pili. LPS, which is responsible for the biological activity of endotoxin, has been investigated fully and 24 somatic antigens have been described. The production of different enzymes by S. marcescens as virulence factors has also been reported, including chitinase, lipase, chloroperoxidase and an extracellular protein, HasA. Antibiotics used to treat serratia infection include beta-lactam agents, aminoglycosides and fluoroquinolones and a variety of different resistance mechanisms have been demonstrated. Typing methods used to study the epidemiology of S. marcescens include biotyping, bacteriocin typing, phage typing, plasmid analysis, polymerase chain reaction amplification of enterobacterial repetitive intergenic consensus sequences (ERIC-PCR) and ribotyping. Serological typing has also been used and this method seems to be a suitable first-line typing method for S. marcescens, although some strains remain untypable. RAPD-PCR has also been applied to a small number of isolates and seems to be a promising method, especially for rapid monitoring of an outbreak and tracing the source of initial infection. PMID- 9368531 TI - The use of RAPD-PCR as a typing method for Serratia marcescens. AB - Serratia marcescens has emerged in the last few years as an important nosocomial pathogen. Many methods for typing this organism have been described. In this study the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) was shown to be a convenient typing method for S. marcescens. Different combinations of primers previously used for typing other gram-negative bacilli were assessed. The combination of primer HLWL-74 and 1254 gave distinguishable patterns for different serotypes and proved to be the most satisfactory. By applying this combination to 175 isolates of S. marcescens, which could be classified into 38 groups on the basis of serotyping and phage typing, 73 different RAPD patterns with good reproducibility were obtained. This is, to our knowledge, the first application of the method to a large collection of S. marcescens representing a wide range of serotypes. PMID- 9368532 TI - Molecular epidemiology of a large outbreak of multiresistant Klebsiella pneumoniae. AB - An outbreak of multiresistant Klebsiella pneumoniae has continued in the Grampian Region of Scotland since 1992. The organism, which generally produces an extended spectrum beta-lactamase (ESBL), has spread to several hospitals and nursing homes. DNA from 80 possible outbreak isolates was digested with the restriction endonucleases XbaI and SpeI, and the patterns obtained by pulsed-field gel electrophoresis were compared. Restriction patterns of 79 of the isolates were found to be highly similar with both restriction enzymes, whereas one isolate was unrelated. The outbreak isolates were divided into six subtypes with SpeI and 16 subtypes with XbaI. These subtypes were independent of antibiotic susceptibility pattern, date of isolation and ward of origin, but the XbaI subtype did correlate with the SpeI subtype. It was concluded that the Klebsiella isolates of this outbreak were clonally related. PMID- 9368533 TI - Simplified analysis of pathogenic leptospiral serovars by random amplified polymorphic DNA fingerprinting. AB - A rapid, simplified procedure combining random amplified polymorphic DNA (RAPD) fingerprinting of boiled cultures with high resolution agarose gel electrophoresis was used to compare strains from 46 pathogenic leptospiral serovars. The serovars were placed in eight groups on the basis of RAPD profile similarities. Groups 1-7 corresponded with the genome species Leptospira interrogans, L. borgpetersenii, L. santarosai, L. noguchii, L. weilii, L. kirschneri and L. meyeri. The eighth group did not correspond with a known genome species and may represent a new genome species. Primer choice determined the degree of discrimination possible between closely related serovars and genotypes. This procedure, unlike other procedures used for analysing taxonomic relationships between leptospiral serovars, does not require extensive DNA purification, polyacrylamide gel electrophoresis or autoradiography. PMID- 9368534 TI - Comparison of three restriction endonucleases in IS1245-based RFLP typing of Mycobacterium avium. AB - IS1245-based restriction fragment length polymorphism (RFLP) analysis has been proposed recently for molecular typing of Mycobacterium avium isolates. As there is no standardised method with respect to the optimal restriction enzyme, three restriction endonucleases were tested for analysis of 17 human isolates. The restriction endonucleases, selected on the basis of the physical maps of IS1245 and of the highly homologous IS1311, were BsaAI, that cleaves IS1245, PvuII, that cleaves IS1311, and NruI, that cleaves both IS1245 and IS1311. All the restriction endonucleases yielded polymorphic and complex RFLP patterns. However, BsaAI- and NruI-generated bands were more evenly distributed and easier to detect than PvuII-generated bands, most of which clustered in a narrow zone of the fingerprint. In some cases, DNA digestion with BsaAI or NruI yielded probe specific restriction fragments of molecular size lower than expected. Moreover, digestion with NruI, which was expected to generate the highest numbers of bands in all the isolates, yielded fewer bands than were obtained with BsaAI or PvuII in 14 and 5 isolates, respectively. These findings might suggest the existence of unidentified IS1245-related insertion element(s) in M. avium isolates. Computer analysis of the IS1245-based RFLP patterns of M. avium isolates showed that the restriction endonucleases were capable, although with minor differences, of defining distinct banding patterns and clusters of identical or highly related isolates, thus confirming IS1245-based RFLP analysis as a useful technique for epidemiological studies. PMID- 9368535 TI - Comparison of Vibrio cholerae O1 isolates by polymerase chain reaction fingerprinting and ribotyping. AB - The rRNA gene restriction patterns and the polymerase chain reaction (PCR) fingerprinting types of 53 Vibrio cholerae O1 isolates were studied. Five and eight patterns were observed from 27 toxigenic and 26 non-toxigenic O1 isolates after BglI cleavage. PCR fingerprinting with three primer sets aimed at enterobacterial repetitive intergenic consensus (ERIC) sequences, ERIC-related sequences in V. cholerae, another kind of repeated sequences in V. cholerae (VCR) and arbitrary sequences divided the same strains into seven and 10 PCR types, respectively. Eight ribotypes had unique PCR patterns. PCR fingerprinting identified more than one pattern among isolates within each of the remaining ribotypes. However, ribotyping was able to differentiate the same PCR types in one case. A single ribotype and a single PCR pattern were found in toxigenic O1 strains isolated in Taiwan from imported food and imported cases of cholera between 1993 and 1995. Typing of V. cholerae O1 by PCR fingerprinting correlated well with ribotyping, but was more discriminating. PCR assay provides a rapid and simple means of typing these strains for epidemiological studies. PMID- 9368536 TI - Restriction endonucleases in clinical isolates of Shigella spp. AB - Thirteen restriction endonuclease-containing strains were isolated from a collection of 186 clinical isolates of Shigella spp. Among these, eight and five isolates carried isoschizomers of EcoRII and NciI, respectively. The former restriction-modification (R-M) system was homologous to that of EcoRII and was located on plasmids with sizes of 46.6 or 55.6 kb. Isolates producing NciI isoschizomers contained a 5.7-kb non-transferable plasmid. Together with antimicrobial susceptibility tests and plasmid profile studies, it is concluded that these two R-M systems are not widely spread but confined to strains with similar antibiotic resistance and plasmid profile. PMID- 9368537 TI - Clostridium difficile toxin A binding to human intestinal epithelial cells. AB - Clostridium difficile radiolabelled toxin A ([3H]-toxin A) bound to human duodenal and colonic epithelial cells isolated from endoscopic biopsies. Binding was greater at 4 degrees C than 37 degrees C, consistent with the thermal binding characteristic of toxin A to a carbohydrate moiety. At 37 degrees C colonic cells bound significantly more [3H]-toxin A than duodenal cells. The amount of [3H] toxin A binding varied considerably between individuals. [3H]-toxin A was displaced by unlabelled toxin A by 50% for duodenal cells and 70% for colonic cells with 94.3 nM unlabelled toxin A. Low non-displacable binding was observed in some samples at 4 degrees C and 37 degrees C, suggesting that these cells came from individuals incapable of specifically binding toxin. Pre-treating cells with alpha- or beta-galactosidases to cleave terminal alpha- and beta-galactose residues reduced [3H]-toxin A binding. There was also a reduction in [3H]-toxin A binding after heat treating cells, which is suggestive of protein binding. The reduction in binding varied between individuals. The reduction of [3H]-toxin A binding, after the removal of beta-linked galactose units, implicates these as components of the receptor and adds credence to the idea that the Lewis X, Y and I antigens may be involved in toxin A binding to human intestinal epithelial cells. However, because the Lewis antigens do not possess terminal alpha galactose units, the reduction in binding after alpha-galactosidase treatment suggests that other receptors may be involved in toxin A binding to some human intestinal cells. These data are the first demonstration of direct toxin A binding to human intestinal epithelial cells. PMID- 9368539 TI - Influence of cardiolipin antibodies on the binding of treponemal specific antibodies in the fluorescence treponemal antibody absorption test and the Treponema pallidum immobilisation test. AB - The aim of the present study was to investigate the biological role of cardiolipin antibodies during Treponema pallidum infection. Inhibition of the binding of treponemal specific antibodies at the early and late stages of infection by cardiolipin antibodies was shown in the fluorescence treponemal antibody absorption (FTA-ABS) test and T. pallidum immobilisation (TPI) test. Incubation of treponemes with cardiolipin antibodies followed by a second incubation with treponemal specific antibodies resulted in a reduction of the titres of the FTA-ABS test and the TPI test. The findings suggest that cardiolipin antibody production should be considered as a virulence mechanism of pathogenic treponemes with the purpose of evading the host defence mechanisms. PMID- 9368538 TI - Diagnosis of Chlamydia pneumoniae infection in patients with chronic obstructive pulmonary disease by micro-immunofluorescence and ELISA. AB - The incidence of Chlamydia pneumoniae infection was determined in patients with chronic obstructive pulmonary diseases (COPD) by prospective serial serology. Chlamydia-specific IgG, IgM and IgA antibodies were detected with a recombinant DNA lipopolysaccharide (LPS) ELISA as well as with a micro-immunofluorescence (MIF) assay with C. pneumoniae elementary bodies. From 271 consecutive COPD patients who visited the outpatient clinic of the department of pulmonary diseases (211 males, 60 females, age range 34-88 years, mean age 66 SD 10 years), blood samples (n = 1058) were taken every 2-7 months; the observation period ranged from 3 to 19 months (mean 15 SD 4). The prevalence of chlamydial IgG was 72% with the MIF and 53% with the rDNA LPS ELISA. More than 90% of the COPD patients had no significant changes in their chlamydia-specific IgG, IgA and IgM titres in either test during the observation period. Seven (3%) patients had MIF results indicating acute C. pneumoniae infection during their surveillance period, of whom five were confirmed by rDNA LPS ELISA. Eleven (4%) additional patients were infected during observation, as determined by rDNA LPS ELISA only. These patients had significantly elevated C. pneumoniae-specific IgG and IgA MIF titres, as compared with the patients without infection. All 18 patients with serological evidence of acute infection during their surveillance period were re tested in a commercial MIF test that can distinguish between C. pneumoniae, C. trachomatis and C. psittaci LPS-specific antibodies, but no evidence of C. trachomatis or C. psittaci infection was found. The incidence of chlamydial infection was 2.2 and 5.3/100 person-years, when diagnosed by MIF and rDNA LPS ELISA, respectively. It is concluded that the rDNA LPS chlamydia assay may currently be the most sensitive serological tool for diagnosing recent respiratory chlamydia infections and that C. pneumoniae infection occurs frequently in COPD patients. PMID- 9368540 TI - The relationship of parental style to depression and self-esteem in adulthood. AB - Previous studies have implicated low parental care and parental overprotection as risk factors for depression in adulthood. The present study further examined the association between perceived parental style and depression in two samples of medical students. In general, both low maternal and paternal care were associated with depression. Furthermore, maternal overprotection in the U.S. sample and paternal overprotection in the Scottish sample were also associated with depression. However, when results were analyzed separately for men and women, clear gender differences emerged, indicating that the observed relationships were occurring chiefly in the men, although there were some indications that low paternal care was associated with depression in women. Because such gender differences have not been previously reported, women medical students may be a unique group with respect to these relationships. Also intriguing was that although parental style characteristics demonstrated significant associations with self-esteem, this was clearly true only for men and not for women. Finally, the study provided the first partial support for the hypothesis that self-esteem mediates the relationship between parental style and depression. PMID- 9368541 TI - Coping with auditory hallucinations: a cross-cultural comparison between western (British) and non-western (Saudi Arabian) patients. AB - The majority of schizophrenic patients from Western backgrounds develop strategies to cope with the positive symptoms of their condition. However, there is little evidence to indicate how these coping mechanisms are affected by cultural background. Seventy schizophrenic patients from Saudi Arabia (SA) and the United Kingdom (UK) who reported auditory hallucinations were interviewed to explore the ways in which they coped with their voices and sounds. Patients from both cultures had several coping mechanisms, but these varied between cultures. The majority of SA patients used strategies associated with their religion whereas UK patients were more likely to use distraction or physiologically based approaches. The majority of patients were slightly or not at all confident about the effectiveness of their coping strategies. This study suggests that clinicians, when they attempt to facilitate the use of such strategies, may find greater patient acceptance and efficacy if they are familiar with culturally specific factors. PMID- 9368542 TI - Comorbid psychiatric disorders in subjects with panic attacks. AB - Several psychiatric disorders are associated with panic disorder (PD), although the nature of their relationships is unknown. The purpose of this study was to a) document comorbid associations with both PD and infrequent panic (IP), and b) investigate the nature of the relationships among these disorders. This community based study included 97 adults who met DSM-III-R criteria for panic attacks compared with 97 matched controls. Psychiatric comorbidity was assessed using the SCID and SCL-90. Subjects with either PD or IP had higher rates of psychiatric comorbidity than controls. PD differed from IP only in its higher rate of phobic avoidance. Factor analysis found three factors: PD with phobic avoidance; substance abuse; major depression with obsessive compulsive disorder, social and simple phobias. Only phobic avoidance began secondary to panic onset. In conclusion, this study supports the PD-agoraphobia DSM-IV grouping while lending support to the common diathesis hypothesis for anxiety and affective disorders. PMID- 9368543 TI - Social support and psychopathology in the war zone. AB - Unit cohesion and homecoming support are examined for their protective effects on the development of posttraumatic stress disorder (PTSD) and other psychopathology. Data on 1198 male theater veterans were taken from the National Vietnam Veterans Readjustment Study. Unit cohesion had no significant relationship, as a direct effect, to either PTSD or other psychopathology. In a pattern that was opposite to predictions from the buffering hypothesis of support, however, a high level of unit cohesion in combination with high war zone stress was associated with the highest levels of PTSD and psychopathology. This is consistent with Israeli experiences, suggesting that unit cohesion may have detrimental long-term effects on psychological well-being. In contrast, homecoming support was related negatively as a direct effect to both PTSD and other psychopathology. In addition, interaction results, consistent with the buffering hypothesis, suggest that the protective effects of homecoming support are magnified for veterans with high compared with low levels of exposure. PMID- 9368544 TI - Posttraumatic stress disorder in U.S. Army Vietnam veterans who served in the Persian Gulf War. AB - We reviewed U.S. Army medical boards (136 cases) held between October 1990 and July 1994 for posttraumatic stress disorder (PTSD) that involved participation in the Persian Gulf War of 1990 to 1991. Thirty-five percent of these soldiers (34 cases) had also served in Vietnam. Their records were compared with the records of 102 other soldiers also medically retired for PTSD who served in the Persian Gulf War but did not serve in Vietnam. Approximately one-half of the Vietnam group developed PTSD symptoms in anticipation of deployment to the Persian Gulf. Those soldiers with prior Vietnam service had statistically significant odds ratios for PTSD (between about 5 and 24) compared with soldiers without Vietnam service. These findings indicate that for some persons with prior war experience, the threat of another war is sufficient to exacerbate symptoms or provoke a new episode of PTSD and this risk is substantially greater than that for soldiers without such experience. PMID- 9368545 TI - Declining prevalence of psychiatric disorder in older former prisoners of war. AB - The aim of this study was to examine change in the prevalence of psychiatric disorders over a decade late in the lives of ex-prisoners of war (POWs) and nonprisoner veterans of World War II. In 1982-83 we drew a random sample of POWs and non-POWs living in Sydney, Australia. They were interviewed by a psychiatrist at that time and again 9 years later. They also completed self-rating anxiety and depression scales. Anxiety disorders were the most prevalent and declined by half from 32.7% at the first interview to 16.8% 9 years later (p < .001) whereas the prevalence of depressive disorders fell by two-thirds from 26.9% to 8.7% (p < .001). In POWs the prevalence of both anxiety and depression declined more markedly than in non-POWs. Consistent changes also occurred in scores on the self rating anxiety and depression scales. The psychological impact of these POWs' tragic wartime experience had at last begun to dim after nearly 50 years. PMID- 9368546 TI - Follow-up study of concentration camp survivors from Bosnia-Herzegovina: three years later. AB - Concentration camp survivors from Bosnia-Herzegovina, now refugees in the Netherlands, were given early outpatient treatment for posttraumatic stress disorder (PTSD) for 6 months. They were tested with the Watson Questionnaire before entering therapy, after 6 months and 3 years later when a structured interview designed to obtain information on psychosocial status was administered. Data were analyzed with PCA-STAT 1.1 statistical package. The treatment was effective on a short-term basis with some long-term effects. Elderly people were no more vulnerable to the onset of PTSD than younger ones but were more resistant to therapy. Psychosocial factors had neither protective nor risk value for the development of PTSD in this group. PMID- 9368547 TI - Neuropsychiatric sequelae of cerebral malaria in Vietnam veterans. AB - Approximately 250,000 Vietnam veterans suffered cerebral malaria, an illness that often results in damage to subcortical white matter and fronto-temporal areas of neocortex. Case reports dating back 2500 years indicate that survivors of cerebral malaria show depression, poor memory, personality change, and irritability/violence. The purpose of the present study was to compare the neuropsychiatric status of Vietnam veterans who had suffered cerebral malaria in the remote past (i.e., 1966 to 1969) with that of Vietnam veterans wounded in combat who had not suffered malaria or other neurological conditions. Findings indicate that cerebral malaria results in multiple, major, substantially underappreciated neuropsychiatric symptoms in Vietnam veterans, including poor dichotic listening, "personality change," depression, and, in some cases, partial seizure-like symptoms. Findings strongly suggest that history of malaria should be considered in any medical, psychological, or psychiatric workup of a Vietnam War veteran because a positive response could result in substantial changes in diagnosis and treatment. PMID- 9368548 TI - Predictors of the development of bulimia nervosa in women with anorexia nervosa. PMID- 9368549 TI - The sexual side effects of an SSRI treated by behavioral methods. PMID- 9368550 TI - Intracerebral hemorrhage after intravenous t-PA therapy for ischemic stroke. The NINDS t-PA Stroke Study Group. AB - BACKGROUND AND PURPOSE: We sought to identify variables associated with intracerebral hemorrhage in patients with acute ischemic stroke who receive tissue plasminogen activator (t-PA). METHODS: We performed subgroup analyses of data from a randomized, double-blind, placebo-controlled trial of intravenous t PA administered to stroke patients within 3 hours of onset. Using multivariable regression modeling procedures, we assessed the relationship of baseline and after-treatment variables with symptomatic and asymptomatic intracerebral hemorrhage during the first 36 hours after treatment. RESULTS: Overall, t-PA treated patients had an increase in the absolute risk of symptomatic intracerebral hemorrhage of 6% and a decrease in the absolute risk of 3-month mortality of 4% compared with placebo-treated patients. The only variables independently associated with an increased risk of symptomatic intracerebral hemorrhage in the final multivariable logistic regression model for the 312 t-PA treated patients were the severity of neurological deficit as measured by the National Institutes of Health Stroke Scale score (five categories; odds ratio [OR], 1.8; 95% confidence interval [CI], 1.2 to 2.9) and brain edema (defined as acute hypodensity) or mass effect by CT before treatment (OR, 7.8; 95% CI, 2.2 to 27.1). This final model correctly predicted those t-PA-treated patients who would or would not have a symptomatic hemorrhage with only 57% efficiency. In the subgroup of patients with a severe neurological deficit, t-PA-treated patients were more likely than placebo-treated patients to have a favorable 3-month outcome (adjusted OR based on multiple outcomes, 4.3; 95% CI, 1.6 to 11.9). These results were similar for the subgroup with edema or mass effect by CT (adjusted OR, 3.4; 95% CI, 0.6 to 20.7). The likelihood of severe disability or death was similar for t-PA- and placebo-treated patients with these two baseline characteristics. CONCLUSIONS: Despite a higher rate of intracerebral hemorrhage, patients with severe strokes or edema or mass effect on the baseline-CT are reasonable candidates for t-PA, if it is administered within 3 hours of onset. PMID- 9368551 TI - Generalized efficacy of t-PA for acute stroke. Subgroup analysis of the NINDS t PA Stroke Trial. AB - BACKGROUND AND PURPOSE: We sought to identify subgroups of stroke patients in whom thrombolytic therapy is particularly hazardous or efficacious. METHODS: We conducted a post hoc subgroup analysis of a randomized, double-blind, placebo controlled clinical trial of intravenous tissue plasminogen activator (t-PA) for stroke patients presenting within 3 hours after symptom onset. Before treatment, historical, physical, and laboratory findings were summarized. We identified variables that might predict outcome and/or differential response to t-PA therapy. Outcome was measured with four stroke rating scales administered 3 months after treatment. Statistical significance was assessed with a global outcome procedure that considers the results of all four scales simultaneously. Using regression analysis, we compared the information collected before treatment with the global outcome. Multivariable procedures were used to find information that could guide selection of patients for t-PA therapy. RESULTS: No pretreatment information significantly affected patients response to t-PA. The power of the model to detect a treatment interaction was greater than 90%, and therefore the probability of a type II error is very low. Apart from t-PA therapy, outcome was related to age-by-deficit severity interaction, diabetes, age-by-blood pressure interaction, and early CT findings. These variables and interactions altered long term patient outcome irrespective of t-PA treatment but did not alter the likelihood of responding favorably to t-PA therapy. CONCLUSIONS: Patients should be selected for t-PA thrombolysis according to the guidelines published in the report of the NINDS t-PA Stroke Trial. Further subselection of patients, such as by age or stroke severity, is not supported by our post hoc analysis. PMID- 9368552 TI - Surgery for primary intracerebral hemorrhage: is it safe and effective? A systematic review of case series and randomized trials. AB - BACKGROUND AND PURPOSE: The surgical treatment of primary intracerebral hemorrhage (PICH) varies throughout the world, mainly because of the lack of evidence of its safety and effectiveness. This study compares the outcome of patients with PICH who are treated surgically with those who are not. METHODS: We conducted a systematic overview (meta-analysis) of all studies of the outcome of surgery for PICH by means of a Medline search of relevant randomized trials and case series published since 1966. Cited references and presentations were also reviewed. RESULTS: The 15 case series of surgery for PICH involving a total of 1524 patients (654 treated surgically) are potentially confounded and the results inconclusive. The pooled results of the three randomized controlled trials of open craniotomy and one trial of endoscopic evacuation for supratentorial PICH in a total of 349 patients (173 treated surgically) indicate a nonsignificant increase in odds of death and dependency at 6 months for patients treated surgically (odds ratio, 1.23; 95% confidence interval, 0.77 to 1.98). The odds of death or dependency at 6 months were 2.1 (1.1 to 4.1) for patients undergoing craniotomy and 0.45 (0.2 to 1.0) for endoscopic evacuation. CONCLUSIONS: There is insufficient evidence of the risks and benefits of surgery for PICH. Further randomized trials are needed to identify whether there is a favorable treatment effect of surgery, the types of PICH and patients who are likely to benefit and not benefit, and the safety and effectiveness of the different surgical interventions. PMID- 9368553 TI - Pharmacological elevation of blood pressure in acute stroke. Clinical effects and safety. AB - BACKGROUND AND PURPOSE: Lowering of blood pressure can adversely affect ischemic symptoms in acute stroke. The aim of our study was to determine whether induced hypertension in stroke is safe and to examine its effects on neurological deficits in patients presenting with acute cerebral ischemia. METHODS: We retrospectively reviewed all patients admitted to our neurological intensive care unit with the diagnosis of ischemic stroke over a 2.5-year period. Thirty-three patients were not given a pressor agent (Ph- group), while 30 were treated with phenylephrine (Ph+ group) in an attempt to improve cerebral perfusion. RESULTS: Baseline characteristics showed few differences between the Ph+ and Ph- groups. Intracerebral hemorrhage, brain edema, cardiac morbidity, and mortality were not increased in the Ph+ group. In 10 of 30 Ph+ patients, a systolic blood pressure threshold was identified below which ischemic deficits worsened and above which deficits improved. The mean threshold was 156 mm Hg (range, 120 to 190 mm Hg). The mean number of stenotic/occluded cerebral arteries was greater in those Ph+ patients with an identified clinical blood pressure threshold (mean, 2.1 per patient) than in Ph+ patients without a threshold (mean, 1.2 per patient; P < .05). CONCLUSIONS: The results suggest that careful use of phenylephrine induced hypertension is not associated with an increase in morbidity or mortality in acute stroke. Although based on a retrospective analysis of clinical practice, this report suggests that a subset of patients, particularly those with multiple stenosis of cerebral arteries, may improve neurologically upon elevation of the blood pressure. PMID- 9368554 TI - How do stroke units improve patient outcomes? A collaborative systematic review of the randomized trials. Stroke Unit Trialists Collaboration. AB - BACKGROUND AND PURPOSE: We sought to clarify the way in which organized inpatient (stroke unit) care can produce reductions in case fatality and in the need for institutional care after stroke. METHODS: We performed a secondary analysis of a collaborative systematic review of all randomized trials that compared organized inpatient (stroke unit) care with contemporary conventional care. Nineteen trials were included, of which 18 (3246 patients) could provide outcome data on death, place of residence, and final functional outcome. Data were less complete (but always available for at least 12 trials; 1611 patients) for subgroup analyses examining timing and cause of death and outcomes in patients with different levels of severity of initial stroke. RESULTS: The reduction in case fatality of patients managed in a stroke unit setting developed between 1 and 4 weeks after the index stroke. The reduction in the odds of death was evident across all causes of death and most marked for those deaths considered to be secondary to immobility. However, data were insufficient to permit a firm conclusion. The relative increase in the number of patients discharged home from stroke units as opposed to conventional care was largely attributable to an increase in the number of patients returning home physically independent. Across the range of stroke severity, stroke unit care was associated with nonsignificant increases in the number of patients regaining independence. CONCLUSIONS: Within the limitations of the available data, we conclude that organized inpatient stroke unit care probably benefits a wide range of stroke patients in a variety of different ways, ie, reducing death from secondary complications of stroke and reducing the need for institutional care through a reduction in disability. PMID- 9368555 TI - Relation of lesion location to verbal and nonverbal mood measures in stroke patients. AB - BACKGROUND AND PURPOSE: The aim of the present study was to evaluate the relation between poststroke depression and lesion location, avoiding previous methodological shortcomings. In particular, we intended to determine whether patients with left frontal lesions showed the highest depression scores. METHODS: Patients in the study, categorized on the basis of lesion location, included 149 stroke patients with lesions located in the anterior, central, or posterior regions of the right or left hemisphere. Verbal and nonverbal mood measures as well as the Hamilton Depression Scale Overall Score were the dependent measures of our investigation. Furthermore, the number of patients who could not be assessed or could be evaluated only with the nonverbal mood measure due to the presence of severe language disorders was recorded. RESULTS: No significant relation was observed between depressed mood and lesion location. Approximately one quarter of the left brain-damaged patients were partially or totally excluded from the study because of severe language disorders. CONCLUSIONS: Our data appeared to show that when methodological pitfalls and selection bias are carefully controlled, left frontal lesions are not a major determinant of poststroke depression. PMID- 9368556 TI - Circadian rhythm of heart rate variability is reversibly abolished in ischemic stroke. AB - BACKGROUND AND PURPOSE: Acute brain infarction significantly decreases heart rate variability as a result of cardiovascular autonomic dysregulation. However, information regarding circadian rhythms of heart rate and heart rate variability is limited. METHODS: In this prospective study, we analyzed 24-hour circadian rhythm of heart rate and the time and frequency domain measures of heart rate variability in 24 patients with hemispheric brain infarction, 8 patients with medullary brainstem infarction, and 32 age- and sex-matched healthy control subjects. ECG data were obtained from the patients in the acute phase and at 6 months after the infarction. RESULTS: In the acute phase of stroke, all the components of heart rate variability, ie, standard deviation of RR intervals, total power, high-frequency power, low-frequency power, and very-low-frequency power, were similar at night (from midnight to 6 AM) and during the day (from 9 AM to 9 PM), indicating that the circadian oscillation of heart rate variability had been abolished. At 6 months after brain infarction, the circadian rhythm had returned and, as in the control subjects, the values at night were significantly higher than those in the daytime. The values in hemispheric and in brainstem infarction did not differ significantly from each other. CONCLUSIONS: These results suggest that circadian fluctuation of heart rate variability is reversibly abolished in the acute phase of ischemic stroke and that it returns during the subsequent 6 months. The loss of the relative vagal nocturnal dominance may contribute to the incidence of cardiac arrhythmias and other cardiovascular complications after acute stroke. PMID- 9368557 TI - A stroke-adapted 30-item version of the Sickness Impact Profile to assess quality of life (SA-SIP30). AB - BACKGROUND AND PURPOSE: In view of the growing therapeutic options in stroke, measurement of quality of life has become increasingly relevant as an outcome parameters. The Sickness Impact Profile (SIP) is one of the most widely used measures to assess quality of life. To overcome the major disadvantage of the SIP, its length, we constructed a short stroke adapted 30-item SIP version (SA SIP30). METHODS: Data on the original SIP version were collected for 319 communicative patients at 6 months after stroke. The 12 subscales and the 136 items of the original SIP were reduced to 8 subscales with 30 items in a three step procedure, on the basis of relevancy and homogeneity. Reliability of the SA SIP30 was evaluated by means of an analysis of homogeneity (Cronbach's alpha coefficient). Different types of validity were assessed: construct, clinical, and external validities. RESULTS: Homogeneity of the SA-SIP30 was demonstrated by a high Cronbach's alpha (0.85). Principal component analyses revealed the same two dimensions as in the original SIP (a physical and a psychosocial dimension). The SA-SIP30 could explain 91% of the variation in scores of the original SIP in the same cohort of patients, and 89% in a different cohort. Furthermore, the SA-SIP30 was related to other functional health measures similar to how the original SIP was. We could demonstrate that the SA-SIP30 was able to distinguish patients with lacunar infarctions from patients with cortical or subcortical lesions. CONCLUSIONS: We conclude that the SA-SIP30 is a feasible and clinimetrically sound measure to assess quality of life after stroke. PMID- 9368558 TI - Computerized measurement of motor performance after stroke. AB - BACKGROUND AND PURPOSE: Stroke scales usually convert motor status to a score along an ordinal scale and do not provide a permanent recording of motor performance. Computerized methods sensitive to small changes in neurological status may be of value for studying and measuring stroke recovery. METHODS: We developed a computerized dynamometer and tested 23 stroke subjects and 12 elderly control subjects on three motor tasks: sustained squeezing, repetitive squeezing, and index finger tapping. For each subject, scores on the Fugl-Meyer and National Institutes of Health stroke scales were also obtained. RESULTS: Sustained squeezing by the paretic hand of stroke subjects was weaker (9.2 kg) than the unaffected hand (20.2 kg; P < .0005), as well as control dominant (23.1 kg; P < .0005) and nondominant (19.9 kg; P < .005) hands. Paretic index finger tapping was slower (2.5 Hz) than the unaffected hand (4.2 Hz; P < .01), as well as control dominant (4.7 Hz; P < .0005) and nondominant (4.9 Hz; P < .0005) hands. Many features of dynamometer data correlated significantly with stroke subjects' Fugl-Meyer scores, including sustained squeeze maximum force (rho = .91) and integral of force over 5 seconds (rho = .91); repetitive squeeze mean force (rho = .92) and mean frequency (rho = .73); and index finger tap mean frequency (rho = .83). Correlation of these motor parameters with National Institutes of Health stroke scale score was weaker in all cases, a consequence of the scoring of nonmotor deficits on this scale. Dynamometer measurements showed excellent interrater (r = .99) and intrarater (r = .97) reliability. CONCLUSIONS: The degree of motor deficit quantitated with the dynamometer is strongly associated with the extent of neurological abnormality measured with the use of two standardized stroke scales. The computerized dynamometer rapidly measures motor function along a continuous, linear scale and produces a permanent recording of hand motor performance accessible for subsequent analyses. PMID- 9368559 TI - Postural dysregulation in systolic blood pressure is associated with worsened scoring on neurobehavioral function tests and leukoaraiosis in the older elderly living in a community. AB - BACKGROUND AND PURPOSE: Postural hypotension, which occurs frequently in community-living, apparently healthy elderly adults, is usually asymptomatic. However, the relation between postural changes in blood pressure and quantitative higher cerebral function or silent brain lesions remains unclear. We examined the association of exaggerated postural changes in systolic blood pressure with cognitive and quantitative neurobehavioral functions and with brain lesions on MRI in the community-dwelling older elderly. METHODS: The study population consisted of 334 community-dwelling elderly adults, aged 75 years or older (mean age, 80 years). Postural changes in systolic blood pressure (SBP) were assessed using an autosphygmomanometer (BP-203 I). By the difference between the mean of two measurements of SBP at standing and at supine position (dSBP = SBP at upright SBP at supine position), we divided the subjects into three groups: (1) 20 subjects with postural hypotension (d-SBP < or = -20 mm Hg), (2) 29 subjects with postural hypertension (dSBP > or = 20 mm Hg), and (3) 285 subjects with postural normotension (20 < dSBP < 20 mm Hg). We defined the former two groups as the postural dysregulation group. Scores in four neurobehavioral function tests (Mini Mental State Exam. Hasegawa Dementia Scale Revised, computer-assisted visuospatial cognitive performance score, and the Up and Go Test) and activities of daily living were compared among the three groups. Brain lesions on MRI, including number of lacunes and periventricular hyperintense lesions, were compared among 15 age- and sex-matched control subjects with postural hypotension, 15 with postural hypertension, and 30 with postural normotension. RESULTS: Twenty subjects (6.0%) exhibited postural hypotension and 29 (8.7%) postural hypertension. Scores in neurobehavioral functions and activities of daily living were significantly lower in the postural dysregulation group (both postural hypotension and hypertension groups) than in the postural normotension group. The postural dysregulation group exhibited significantly more advanced periventricular hyperintensities than the normotension group. CONCLUSIONS: Asymptomatic community dwelling elderly individuals with postural hypotension as well as those with postural hypertension had poorer scores on neurobehavioral function tests and more advanced leukoaraiosis demonstrated on MRI than those without exaggerated postural changes in SBP. PMID- 9368560 TI - Effect of extracranial carotid artery stenosis and other risk factors for stroke on periventricular hyperintensity. AB - BACKGROUND AND PURPOSE: The pathogenesis of periventricular hyperintensity (PVH) is still uncertain. We investigated the relationship between PVH and risk factors for cerebrovascular diseases, especially extracranial carotid artery stenosis (ECAS). METHODS: We studied PVH and ECAS in 323 subjects between 1991 and 1994. Using 1.5-T MRI scan images, we measured PVH quantitatively at eight points and evaluated cerebral infarction. Duplex carotid sonography was performed on the carotid arteries bilaterally and used to divide the severity of ECAS into five grades. Risk factors for cerebrovascular diseases and atherosclerotic complications were assessed from the clinical history. RESULTS: Age was significantly correlated with the size of frontal and whole PVH (P < .01). Frontal PVH was significantly more severe in subjects with hypertension (P < .05). Frontal, occipital, and whole PVH were significantly more severe in subjects with a history of cerebrovascular accident (P < .01). Other risk factors and atherosclerotic complications were not correlated with PVH. There were no significant differences in the severity of PVH among the five groups of ECAS. The severity of PVH in each region was not related to ECAS. There was no significant difference in the age of patients in relation to the five grades of ECAS. However, PVH was significantly more severe in subjects with lacunar infarction or infarction of the deep border zone (P < .05). There was no relationship between PVH and cortical infarction or infarction of the cortical border zone. CONCLUSIONS: PVH correlated with age, hypertension, and past history of cerebrovascular disease but not with ECAS. PVH was significantly more severe in lacunar infarction and infarction of the deep border zone. These results suggest that small-vessel disease may underlie the pathogenesis and development of PVH. PMID- 9368561 TI - Epidemiology of stroke in Innherred, Norway, 1994 to 1996. Incidence and 30-day case-fatality rate. AB - BACKGROUND AND PURPOSE: In Norway, as well as other industrialized countries, mortality from stroke has declined over the past decades. Data on stroke morbidity are lacking. This study was conducted to determine the incidence, case fatality, and risk factors of stroke in a defined Norwegian population. METHODS: During the period 1994 to 1996, a population-based stroke registry collected uniform information about all cases of first-ever and recurrent stroke occurring in people aged > or = 15 years in the region of Innherred in the central part of Norway (target population 70,000), where the prevalence of cardiovascular risk factors was screened in 1984 to 1986 and 1995 to 1997. RESULTS: During the 2 years of registration (September 1, 1994, to August 31, 1996), 432 first-ever (72.8%) and 161 recurrent (27.2%) strokes were registered. The crude annual incidence rate was 3.12/1000 (2.85/1000 for males and 3.38/1000 for females). Adjusted to the European population, the annual incidence rate of first-ever stroke was 2.21/1000. The annual incidence rate of cerebral infarction was 2.32/1000, intracerebral hemorrhage 0.32/1000, subarachnoid hemorrhage 0.19/1000, and unspecified stroke 0.38/1000. The 30-day case-fatality rate was 10.9% for cerebral infarction, 37.8% for intracerebral hemorrhage, and 50.0% for unspecified stroke. Fourteen percent of the patients were found outside the hospital, and only 50% of the suspected stroke cases in the hospital (at admission or reviewed discharge diagnosis of ICD-9 codes 430 to 438) fitted the final inclusion criteria. CONCLUSIONS: This first population-based stroke register in Norway revealed incidence rates of stroke similar to other Scandinavian countries, and comparison between other European countries did not indicate regional variations within Western Europe. PMID- 9368562 TI - Valvular strands and cerebral ischemia. Effect of demographics and strand characteristics. AB - BACKGROUND AND PURPOSE: Valvular strands, thin filamentous material attached to the mitral or aortic valve, are seen during transesophageal echocardiography and have been associated with stroke. Little is known about this association in different age, sex, and race-ethnic subgroups and the effect of various strand characteristics on this association. METHODS: From patients referred for transesophageal echocardiography, 73 patients with recent ischemic stroke (68) or transient ischemic attack (5) were age matched to 73 stroke- and transient ischemic attack-free control subjects. The association between valvular strands and cerebral ischemia was evaluated for the overall group and demographic subgroups. The effect of strand location, length, number, and valve thickness was also determined. RESULTS: An association between cerebral ischemia and valvular strands was observed (odds ratio [OR] = 4.4; 95% confidence interval [CI] = 2.0 to 9.6). The association was found for both men and women and among all three race-ethnic groups. The OR was greater in those who were younger (12.5 [95% CI = 2.4 to 64.5] for age < 60, 4.8 [95% CI = 1.3 to 18.2] for age 60 to 69, and 1.8 [95% CI = 0.5 to 6.4] for age > or = 70 years). Strands on both the mitral (OR = 3.5; 95% CI = 1.5 to 7.9) and aortic (OR = 3.7; 95% CI = 1.1 to 11.9) valve were associated with cerebral ischemia, whereas the number and length of strands were not. The effect of strands was independent of mitral or aortic valve thickness. CONCLUSIONS: Valvular strands, whether mitral or aortic, are associated with ischemic stroke, especially among younger persons. PMID- 9368563 TI - Influence of oxygen ventilation on Doppler microemboli signals in patients with artificial heart valves. AB - BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the influence of inhalation of 100% oxygen on microembolic signal (MES) counts in patients with artificial cardiac valves. METHODS: A total of 134 outpatients were examined. Transcranial Doppler baseline monitoring (45-minute duration) was performed in all patients under resting conditions. The first 30 patients subsequently underwent transcranial Doppler monitoring for at least 20 minutes under noninvasive positive pressure ventilation with 100% oxygen and for an additional 30 minutes under resting conditions. The same protocol was applied to all following patients with a baseline MES count > or = 10, while the examination was discontinued in the remaining patients. RESULTS: Baseline MES counts < 10, which remained unchanged during oxygen inhalation and the subsequent resting period, were observed in 26 of 30 initial patients. A total of 46 patients with MES counts > or = 10 were identified. Oxygen application was feasible in 43 patients. An exponential MES decrease was noted in 42 patients during oxygen inhalation (statistically significant in 38 patients), followed by a subsequent increase in 38 of 43 patients (statistically significant in 25 patients) under resting conditions. CONCLUSIONS: The exponential reduction of MES counts observed in this study corresponds to blood denitrogenation, thus strongly arguing for nitrogen bubbles as underlying embolic material in prosthetic valve carriers. PMID- 9368564 TI - A new automated computerized analyzing system simplifies readings and reduces the variability in ultrasound measurement of intima-media thickness. AB - BACKGROUND AND PURPOSE: A computerized analyzing system with manual tracing of echo interfaces for measurement of intima-media thickness and lumen diameter in carotid and femoral arteries was previously developed by our research group and has been used for many years in several laboratories. However, manual measurements are not only time consuming, but the results from these readings are also dependent on training and subjective judgement. A further problem is the observed drift in measurements over time. A new computerized technique for automatic detection of echo interfaces was therefore developed. The aim of this study was to evaluate the new automated computerized analyzing system. METHODS: The new system is based on dynamic programming and includes optional interactive modification by the human operator. Local measurements of vessel echo intensity, intensity gradient, and boundary continuity are extracted by image analysis techniques and included as weighed terms in a cost function. The dynamic programming procedure is used for determining the optimal location of the vessel interfaces in a way that the cost function is minimized. RESULTS: With the new automated computerized analyzing system the measurement results were less dependent on the reader's experience, and the variability between readers was less compared with the old manual analyzing system. The measurements were also less time consuming. CONCLUSIONS: The new automated analyzing system will not only greatly increase the speed of measurements but also reduce the variability between readers. It should also reduce the variability between different laboratories if the same analyzing program is used. Furthermore, the new system will probably prevent the problem with drift in measurements over time. PMID- 9368565 TI - Reproducibility of ultrasound assessment of carotid plaque occurrence, thickness, and morphology. The Tromso Study. AB - BACKGROUND AND PURPOSE: Ultrasonography is increasingly used in vascular research, but there is limited information about the reproducibility of the ultrasound method for screening purposes. In this study the reproducibility of ultrasound assessment of carotid plaque occurrence, thickness, and morphology was examined within the setting of a population health survey. METHODS: In 1994/1995, 6720 participants in the Tromso Study, Norway, underwent B-mode ultrasound scanning of the right carotid artery. The between- and within-sonographer reproducibility of ultrasound assessment of plaque occurrence and thickness was estimated by repeated scanning of a random sample of 107 participants. The between- and within-sonographer reproducibility of plaque morphology classification (echogenicity, four categories and heterogeneity, two categories) was determined by repeated reading of videotaped images of 119 randomly selected arteries with plaques. RESULTS: Between- and within-sonographer agreement on plaque occurrence was substantial with kappa values (95% CI) of 0.72 (0.60 to 0.84) and 0.76 (0.63 to 0.89), respectively. Reproducibility of plaque thickness measurements was moderate, with mean absolute differences ranging between 0.25 and 0.55 mm (coefficients of variation between 13.8% and 22.4%). Agreement on plaque morphology classification was high, with kappa values ranging between 0.54 and 0.73. CONCLUSIONS: Population screening using B-mode ultrasound provides a valuable means for the detection and morphological evaluation of carotid plaques, whereas measurements of plaque thickness are subject to considerable measurement error. PMID- 9368566 TI - Quantitative cerebral blood flow determinations in acute ischemic stroke. Relationship to computed tomography and angiography. AB - BACKGROUND AND PURPOSE: The advent of new modalities to treat acute ischemic stroke presents the need for accurate, early diagnosis. In acute ischemic stroke, CT scans are frequently normal or reveal only subtle hypodense changes. This study explored the utility and increased sensitivity of xenonenhanced CT (XeCT) in the diagnosis of acute cerebral ischemia and investigated the relationship between cerebral blood flow (CBF) measurements and early CT and angiographic findings in acute stroke. METHODS: The CT scans, XeCT scans, and angiograms of 20 patients who presented within 6 hours of acute anterior circulation ischemic strokes were analyzed. RESULTS: CT scans were abnormal in 11 (55%) of 20 patients. XeCT scans were abnormal in all 20 (100%) patients, showing regions of interest with CBF < 20 (mL/100 g per minute) in the symptomatic middle cerebral artery (MCA) territories. The mean CBF in the symptomatic MCA territories was significantly lower than than of the asymptomatic MCA territories (P < .0005). In patients with basal ganglia hypodensities, the mean symptomatic MCA territory CBF was significantly lower than that of patients who did not exhibit these early CT findings (P < .05). The mean symptomatic MCA territory CBF in patients with angiographic M1 occlusions was significantly lower than that of patients whose infarcts were caused by MCA branch occlusions (P < .01). CONCLUSIONS: These results show that XeCT is more sensitive than CT in detecting acute strokes and that CBF measurements correlate with early CT and angiographic findings. XeCT may allow for the hyperacute identification of subsets of patients with acute ischemic events who are less likely to benefit and more likely to derive complications from aggressive stroke therapy. PMID- 9368568 TI - Association of presenilin-1 polymorphism with cerebral amyloid angiopathy in the elderly. AB - BACKGROUND AND PURPOSE: An intronic polymorphism of presenilin-1 (PS-1), a gene responsible for early-onset familial Alzheimer's disease, has been reported to be associated with late-onset sporadic Alzheimer's disease. In a search for a genetic risk factor of sporadic cerebral amyloid angiopathy (CAA), we investigated the association of the polymorphism of PS-1 with CAA. METHODS: The association between the severity of CAA and genotypes of a polymorphism in intron 8 of PS-1 was investigated in 137 autopsy cases of the elderly. RESULTS: A significant decrease of PS-1 2/2 genotype frequency was associated with severe or moderate CAA. CONCLUSIONS: Our results suggest that PS-1 intronic polymorphism may be associated with the severity of CAA in the elderly. PMID- 9368567 TI - Soluble adhesion molecules reflect endothelial cell activation in ischemic stroke and in carotid atherosclerosis. AB - BACKGROUND AND PURPOSE: Activation of endothelial cells and platelets plays an important role in the development of atherosclerosis and thrombotic disorders. Soluble adhesion molecules originating from these cells can be demonstrated in plasma. We hypothesized that elevated plasma concentrations of soluble P-selectin (sP-selectin), soluble intercellular adhesion mole-cule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and soluble E-selectin (sE-selectin) can reflect activation of endothelial cells and/or platelets in acute ischemic stroke and in previously symptomatic internal carotid artery stenosis. METHODS: Plasma was sampled from patients within 2 days of acute ischemic stroke (n = 28), from patients with a previous (> 1 week) transient or persistent ischemic neurological deficit associated with stenosis of the internal carotid artery (n = 34), and from control patients without a history of vascular disease (n = 34). Concentrations of sP-selectin, sICAM-1, sVCAM-1, and sE-selectin were measured by means of an enzyme-linked immunosorbent assay. RESULTS: Compared with control subjects, sP-selectin and sE-selectin were significantly elevated in the acute stage of ischemic stroke (P < .0001 and P = .001, respectively) as well as in previously symptomatic carotid stenosis (P < .0001 and P = .0007). sICAM-1 and sVCAM-1 were not increased. CONCLUSIONS: The elevated levels of sE-selectin indicate that endothelial cell activation occurs both in the acute stage of ischemic stroke and in previously symptomatic carotid atherosclerosis. Increased sP-selectin concentrations reflect endothelial cell activation as well but may also be caused by platelet activation. PMID- 9368569 TI - Nonhypertensive cerebral small-vessel disease. An autopsy study. AB - BACKGROUND AND PURPOSE: Cerebral small-vessel disease (SVD) is a common aging phenomenon that is exacerbated by hypertension and diabetes mellitus. It is regarded as an important cause of lacunar infarction and intracerebral hemorrhage. The present study was performed to highlight the existence and to some extent the frequency of pathologically verified SVD lacking in classic risk factors and to extend the scope of risk factor analysis. METHODS: The study group comprised 70 consecutively referred autopsy brains with microscopic evidence of SVD. In each case clinical records, autopsy reports, and central nervous system and systemic autopsy histology were reviewed. SVD was graded as mild, moderate, or severe in six standardized brain regions, and the results analyzed in relation to the presence or absence of classic SVD risk factors. RESULTS: SVD was manifest largely as concentric hyaline wall thickening; lipohyalinosis and fibrinoid necrosis were rarely observed. Thirty-one percent of cases failed to meet stringent clinicopathological criteria for significant prior hypertension. In 9% of cases, patients had been nonelderly, nondiabetic, and normotensive. Five of six cases lacking classic risk factors had systemic conditions known to enhance small-vessel permeability. CONCLUSIONS: The nature of SVD appears to have been modified by effective treatment of hypertension. Classic risk factors are often absent. The hypothesis that a variety of conditions that enhance small-vessel permeability may contribute to the pathogenesis of SVD merits consideration. PMID- 9368570 TI - Lamotrigine protects hippocampal CA1 neurons from ischemic damage after cardiac arrest. AB - BACKGROUND AND PURPOSE: Lamotrigine (LTG) is an anticonvulsant drug whose mechanism of action may involve the inhibition of glutamate release by blocking voltage-dependent sodium channels. Glutamate neurotoxicity may contribute to cerebral ischemic damage after recovery from cardiac arrest. Thus, LTG may prevent the brain damage associated with global cerebral ischemia by reducing the release of glutamate from presynaptic vesicles during the ischemic insult or the early recovery period. METHODS: LTG was studied in cardiac arrest-induced global cerebral ischemia with reperfusion in rats. In the first set of experiments, LTG (100 mg/kg, p.o.) was administered before induction of ischemia; and in the second experiment, LTG (10 mg/kg, i.v.) was given 15 minutes after ischemia and a second dose (10 mg/kg,i.v.) was given 5 hours later. RESULTS: In both experiments LTG reduced the damage to the hippocampal CA1 cell population by greater than 50%. Neuroprotection was not associated with changes in brain temperature or plasma glucose concentration. Plasma concentrations of LTG ranged between 8 and 13 micrograms/mL. Patients taking LTG as a monotherapy for epilepsy typically have plasma levels of LTG in the 10 to 15 micrograms/mL range. CONCLUSIONS: These data suggest that LTG may be effective in preventing brain damage after recovery from cardiac arrest. Patients on LTG monotherapy for epilepsy have plasma concentrations very similar to those found to be neuroprotective in this study. Although difficult to extrapolate, our data suggest that LTG at neuroprotective doses may be well tolerated by humans. PMID- 9368571 TI - Hypothermic neuroprotection. A global ischemia study using 18- to 20-month-old gerbils. AB - BACKGROUND AND PURPOSE: Previous studies from this laboratory have shown that mild intraischemic or prolonged (i.e., 12 to 24 hours) postischemic hypothermia conveys long-lasting (1 to 6 months) protection against CA1 injury. However, these studies have used young animals (aged approximately 3 to 5 months). Stroke incidence rises sharply in late middle age at a time when changes in brain chemistry could alter the response to neuroprotective treatments. Therefore, we evaluated the efficacy of hypothermia in an older population (aged 18 to 20 months) of gerbils. METHODS: Three groups of gerbils were exposed to a 5-minute episode of global ischemia or sham occlusion. One group was cooled during ischemia (mean brain temperature of 32 degrees C). A second group was maintained at normothermia (36.4 degrees C) during occlusion and the first hour of reperfusion. Beginning 1.0 hour after occlusion, these gerbils were gradually cooled to 32 degrees C and maintained at this level before gradual rewarming to 37 degrees C at 25 hours after ischemia. The third ischemic group was kept at normothermia during surgery and the first hour of reperfusion. After surgery, all animals were tested for acute (i.e., within 30 hours of ischemia) changes in locomotor activity as well as for chronic (i.e., 5, 10, and 30 days after ischemia) habituation deficits in an open field test. RESULTS: Both intraischemic and postischemic hypothermia provided robust protection (P < .0001) of hippocampal CA1 neurons when assessed 30 days after ischemia. However, intraischemic hypothermia was more effective than postischemic hypothermia in providing behavioral protection. CONCLUSIONS: This study demonstrates that both intraischemic and prolonged postischemic hypothermia provide robust and lasting (30-day survival) histological protection against a severe ischemic insult. The extent of behavioral protection with postischemic hypothermia was less than that previously observed in younger animals. This suggests that neuroprotective treatments in young animals may lose efficacy as a result of aging. PMID- 9368572 TI - Effect of CP101,606, a novel NR2B subunit antagonist of the N-methyl-D-aspartate receptor, on the volume of ischemic brain damage off cytotoxic brain edema after middle cerebral artery occlusion in the feline brain. AB - BACKGROUND AND PURPOSE: The purpose of this study was to test the hypothesis that the neuroprotective compound CP101,606 will ameliorate the increase in lactate, retard the development of cytotoxic edema, and decrease the infarct volume after ischemic stroke. METHODS: Seventeen adult cats were allocated to control (n = 7) and CP101,606-treated groups (n = 10). Transorbital middle cerebral artery occlusion was performed under anesthesia. Extracellular fluid lactate by microdialysis as well as infarct volume measurement by triphenyltetrazolium chloride (TTC)-stained section, with and without neuroprotective agents, was used to determine the value of these potential "surrogate markers" of ischemic damage. RESULTS: The control group showed an increased dialysate lactate (15.5% increase) at 30 minutes and a peak (332.0% increase) in dialysate lactate at 1 hour after middle cerebral artery occlusion compared with the drug-treated group. Significant differences between control and drug-treated groups were seen in the rate of fall of the apparent diffusion coefficient at both 1 and 5 hours. A close correlation was seen between the 1- and 5-hour apparent diffusion coefficient maps and the TTC-stained sections. There was a significantly smaller lesion in the CP101,606-treated group (62.9% reduction in infarct size compared with the control group; P < .001). CONCLUSIONS: CP101,606 ranks very highly among the current neuroprotection candidates for clinical trials, and its excellent safety record in both animals and phase II studies in conscious, moderate head injury patients suggests that it will be highly effective in human occlusive stroke. PMID- 9368573 TI - Ischemic stroke injury is reduced in mice lacking a functional NADPH oxidase. AB - BACKGROUND AND PURPOSE: Free radicals account for a significant proportion of the brain damage that occurs during ischemic stroke. Using mutant mice (X-CGD) with a dysfunctional phagocytic NADPH oxidase, we investigated the role of this superoxide-generating enzyme as a mediator of the reperfusion injury in a mouse model of middle cerebral artery occlusion. METHODS: Transient (2 hour) middle cerebral artery occlusion was performed in X-CGD or wild-type litter mates (8- to 10-week-old). After 22 hours of reperfusion, brains were harvested and infarct volume delineated using 2,3,5-triphenyl-tetrazolium chloride. To elucidate the origin of the damaging NADPH oxidase, transient ischemia was also performed in X CGD or wild-type mice transplanted with wild-type C57 B1/6J or X-CGD bone marrow, respectively. RESULTS: The infarct volume induced by transient ischemia was significantly less in X-CGD mice (29.1 +/- 5.6 mm3; n = 13) than wild-type littermates (54.0 +/- 10.6 mm3; n = 10; P < .05). The elimination of a functional NADPH oxidase from either the circulation or the central nervous system, by performing the appropriate bone marrow transplant experiments, did not reduce the infarct size induced by transient ischemia. This suggests that in order to confer protection against transient ischemia and reperfusion, a putative neuronal and circulating NADPH oxidase need to be inactivated. CONCLUSIONS: Brain injury was reduced in mice lacking a functional NADPH oxidase in both the central nervous system and peripheral leukocytes, suggesting a pivotal role for the NADPH oxidase in the pathogenesis of ischemia-reperfusion injury in the brain. PMID- 9368574 TI - Neither L-arginine nor L-NAME affects neurological outcome after global ischemia in cats. AB - BACKGROUND AND PURPOSE: We attempted to determine whether N-nitro-L-arginine methyl ester (L-NAME) would improve neurological outcome and whether L-arginine (L-ARG) would worsen neurological outcome after transient global ischemia. METHODS: Halothane-anesthetized cats (n = 6 for each group) were treated with intravenous saline, L-NAME (5 mg/kg or 10 mg/kg), or L-arginine (300 mg/kg) 30 minutes before 10 minutes of ischemia (temporary ligation of the left subclavian and brachiocephalic arteries with hemorrhagic hypotension to 50 mm Hg). At 30 minutes of reperfusion, cats in the L-ARG group were administered an additional 300 mg/kg dose of intravenous L-arginine. RESULTS: Time (mean +/- SE) to isoelectric electroencephalography was similar among groups (saline, 26 +/- 11 seconds; L-NAME-5, 15 +/- 4 seconds; L-NAME-10, 36 +/- 27 seconds; and L-ARG, 22 +/- 7 seconds). At 72 hours, reperfusion pathological injury was severe and neurological deficit score (mean, range) was similar among groups (saline, 38[11 to 70]; L-NAME-5, 52 [40 to 73]; L-NAME-10, 47 [23 to 70]; and L-ARG, 40 [0 to 79]). CONCLUSIONS: Nitric oxide is not important in the mechanism of brain injury after global ischemia in cats. PMID- 9368575 TI - Mildly oxidized low-density lipoprotein impairs responses of carotid but not basilar artery in rabbits. AB - BACKGROUND AND PURPOSE: Intracranial blood vessels appear to be relatively resistant to development of atherosclerosis. The goal of this study was to compare effects of mildly oxidized LDL (ox-LDL) on endothelium-dependent responses of intracranial and extracranial arteries in vitro. METHODS: LDL was purified from plasma of healthy subjects and mildly oxidized by means of a xanthine/xanthine oxidase reaction. Contraction of the rabbit basilar and carotid arteries in response to histamine and phenylephrine and relaxation in precontracted vessels to acetylcholine and sodium nitroprusside were evaluated after 30 minutes of exposure to LDL or ox-LDL (100 micrograms/mL). RESULTS: Exposure to LDL had little or no effect on vascular responses. After exposure to ox-LDL, contraction to histamine and phenylephrine and relaxation to acetylcholine were impaired significantly in carotid (P < .05) but not in basilar artery. Relaxation to sodium nitroprusside was not significantly impaired by ox LDL in the basilar artery. In the carotid artery, relaxation to sodium nitroprusside was significantly impaired by ox-LDL when the vessels were precontracted with phenylephrine but not histamine. Impairment of vascular responses by ox-LDL was prevented by addition of superoxide dismutase, catalase, or dimethylthiourea to the LDL solution before addition of xanthine/xanthine oxidase. CONCLUSIONS: Mildly ox-LDL impairs contraction and endothelium-dependent relaxation in the carotid but not in basilar artery. Thus, intracranial arteries may be relatively resistant to mildly ox-LDL. PMID- 9368576 TI - Brain injury impairs ATP-sensitive K+ channel function in piglet cerebral arteries. AB - BACKGROUND AND PURPOSE: Traumatic injury is the leading cause of death for infants and children, and mortality is increased with head injury. Previous studies have shown that pial arteries constricted and that responses to several nitric oxide (NO)-dependent dilator stimuli were blunted after fluid percussion injury (FPI) in newborn pigs. Membrane potential of vascular muscle is a major determinant of vascular tone, and activity of K+ channels is a major regulator of membrane potential. Recent data show that the NO releasers sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine (SNAP) and 8-bromo-cGMP elicit dilation via ATP-sensitive K+ channel (KATP) activation. The present study was designed to investigate the effect of FPI on KATP channel function. METHODS: Chloralose anesthetized newborn pigs equipped with a closed cranial window were connected to a percussion device that consisted of a saline-filled cylindrical reservoir and a metal pendulum. Brain injury of moderate severity (1.9 to 2.1 atm) was produced by allowing the pendulum to strike a piston on the cylinder. Pial artery diameter was measured with a video microscaler. Data were analyzed by repeated measures ANOVA. An alpha level of P < .05 was considered significant. RESULTS: FPI blunted dilation to cromakalim (10(-8), 10(-6) mol/L), a KATP agonist (10 +/- 1% and 27 +/- 2% versus 3 +/- 1% and 7 +/- 2% before and after FPI, respectively, n = 8). Similarly, FPI blunted dilation to calcitonin gene-related peptide, an endogenous KATP activator. FPI also blunted dilator responses to SNP, S-nitroso-N acetylpenicillamine, and 8-bromo-cGMP (10(-6) to 10(-8) mol/L) (10 +/- 1% and 20 +/- 1% versus 2 +/- 1% and 8 +/- 2% for SNP before and after FPI; 9 +/- 1% and 16 +/- 1% versus 2 +/- 1% and 4 +/- 1% for 8-bromo-cGMP before and after FPI, respectively, n = 8). In contrast, responses to papaverine and brain natriuretic peptide were unchanged after FPI. CONCLUSIONS: These data show that KATP channel function is impaired after FPI. Furthermore, these data suggest that impaired function of mechanisms distal to NO synthase contribute to altered cerebral hemodynamics after FPI. PMID- 9368577 TI - Vulnerability to cerebral hypoxic-ischemic insult in neonatal but not in adult rats is in parallel with disruption of the blood-brain barrier. AB - BACKGROUND AND PURPOSE: Vulnerability to cerebral hypoxic-ischemic (H-I) insult and its relation to disruption of the blood-brain barrier were investigated in postnatal rats. METHODS: Pups of postnatal day (P) 7, P14, and P21 underwent ligation of a unilateral carotid artery and were exposed to hypoxic conditions. For the detection of early-phase deterioration, brains were perfusion-fixed 24 hours after H-I insult and examined by argyrophil III method. For the detection of later infarction, animals were fixed at 72 hours after the H-I insult. RESULTS: In either case, tissue damage was detected in the striatum, parietal cortex, and hippocampus. The vulnerability of P7 and P21 rats was remarkable, as compared with P14 rats. Although the developmental status of the vasculature was not significantly different at each age, the permeability of IgG after H-I injury was prominent in P7 rats and to a lesser extent in P14 rats. In P21 rats, however, there was little IgG leakage even 24 hours after the insult. Dexamethasone pretreatment blocked the extravasation of IgG and reduced the damaged tissue in P7 and P14 rats but not in P21 rats. Percentages of reduction in infarcted areas by the dexamethasone became smaller in proportion to ages. CONCLUSIONS: The results suggest that in younger rats vulnerability to H-I insult was in parallel with permeability of the blood-brain barrier, whereas in adults in might be more dependent on cellular vulnerability. PMID- 9368578 TI - Mechanisms of bradykinin-induced cerebral vasodilatation in rats. Evidence that reactive oxygen species activate K+ channels. AB - BACKGROUND AND PURPOSE: Relatively little is know regarding mechanisms by which reactive oxygen species produce dilatation of cerebral arterioles. The goal of this study was to test the hypothesis that vasodilator responses of cerebral arterioles to bradykinin, which produces endogenous generation of reactive oxygen species, involve activation of calcium-dependent potassium channels. METHODS: We used a cranial window in anesthetized rats to examine effects of catalase (which degrades hydrogen peroxide) on responses to bradykinin. In addition, we examined effects of tetraethylammonium (TEA) and iberiotoxin, inhibitors of calcium dependent potassium channels, on responses of cerebral arterioles to hydrogen peroxide, bradykinin, and papaverine. RESULTS: In cerebral arterioles (baseline diameter = 40 +/- 1 microns) (mean +/- SE), hydrogen peroxide (10 and 100 mumol/L) produced concentration-dependent dilatation. TEA (1 mmol/L), an inhibitor of calcium-dependent potassium channels, produced marked inhibition of vasodilatation in response to hydrogen peroxide. For example, 100 mumol/L hydrogen peroxide dilated arterioles by 13 +/- 2% in the absence and 4 +/- 1% (P < .05 versus control) in the presence of TEA. Bradykinin (10 nmol/L to 1 mumol/L) also produced concentration-dependent dilatation of cerebral arterioles that was inhibited completely by catalase (100 U/mL). TEA or iberiotoxin markedly inhibited vasodilatation in response to bradykinin. For example, 100 nmol/L bradykinin dilated arterioles by 21 +/- 3% in the absence and 2 +/- 2% (P < .05 vs control) in the presence of iberiotoxin (50 nmol/L). CONCLUSIONS: These findings suggest that dilatation of cerebral arterioles in the rat in response to hydrogen peroxide, or hydrogen peroxide produced endogenously in response to bradykinin, is mediated by activation of calcium-dependent potassium channels. Thus, activation of potassium channels may be a major mechanism of dilatation in response to reactive oxygen species in the cerebral microcirculation. PMID- 9368579 TI - Use of a spectrophotometric hemoglobin assay to objectively quantify intracerebral hemorrhage in mice. AB - BACKGROUND AND PURPOSE: There is great interest in developing novel anticoagulant or thrombolytic strategies to treat ischemic stroke. However, at present there are limited means to accurately assess the hemorrhagic potential of these agents. The present studies were designed to develop and validate a method to accurately quantify the degree of intracerebral hemorrhage (ICH) in murine models. METHODS: In a murine model, ICH was induced by stereotaxic intraparenchymal infusion of collagenase B alone (6 x 10(-6) U; n = 5) or collagenase B followed by intravenous recombinant tissue plasminogen activator (rt-PA) (0.1 mg/kg; n = 6). Controls consisted of either sham surgery with stereotaxic infusion of saline (n = 5) or untreated animals (n = 5). ICH was (1) graded by a scale based on maximal hemorrhage diameter on coronal sections and (2) quantified by a spectrophotometric assay measuring cyanomethemoglobin in chemically reduced extracts of homogenized murine brain. This spectrophotometric assay was validated with the use of known quantities of hemoglobin or autologous blood added to a separate cohort of homogenized brains. With this assay, the degree of hemorrhage after focal middle cerebral artery occlusion/reperfusion was quantified in mice treated with postocclusion high-dose intravenous rt-PA (10 mg/kg; n = 11) and control mice subjected to stroke but treated with physiological saline solution (n = 9). RESULTS: Known quantities of hemoglobin or autologous blood added to fresh whole brain tissue homogenates showed a linear relationship between the amount added and optical density (OD) at the absorbance peak of cyanomethemoglobin (r = 1.00 and .98, respectively). When in vivo studies were performed to quantify experimentally induced ICH, animals receiving intracerebral infusion of collagenase B had significantly higher ODs than saline-infused controls (2.1-fold, increase; P = .05). In a middle cerebral artery occlusion and reperfusion model of stroke, administration of rt-PA after reperfusion increased the OD by 1.8-fold compared with animals that received physiological saline solution (P < .001). When the two methods of measuring ICH (visual score and OD) were compared, there was a linear correlation (r = .88). Additional experiments demonstrated that triphenyltetrazolium staining, which is commonly used to stain viable brain tissue, does not interfere with the spectrophotometric quantification of ICH. CONCLUSIONS: These data demonstrate that the spectrophotometric assay accurately and reliably quantifies murine ICH. This new method should aid objective assessment of the hemorrhagic risks of novel anticoagulant or thrombolytic strategies to treat stroke and can facilitate quantification of other forms of ICH. PMID- 9368581 TI - Diffusion-weighted MRI in transient global amnesia precipitated by cerebral angiography. AB - BACKGROUND: Transient global amnesia is a well-described complication of cerebral angiography. Speculation about the pathophysiology exists but is as yet unsubstantiated. Diffusion-weighted MRI is a new imaging technique that is very sensitive in detecting acute ischemia. Its use in the evaluation of transient amnesia precipitated by cerebral angiography has not previously been reported. CASE DESCRIPTION: A 44-year-old man underwent posterior circulation cerebral angiography for the investigation of episodic vertigo. Shortly after completion of the procedure, he was noted to have symptoms of transient global amnesia. Diffusion-weighted MRI at 6 and 44 hours after the procedure demonstrated increased signal in the right hippocampus and other areas within the posterior circulation bilaterally consistent with ischemia from emboli. Abnormalities on conventional MRI images performed at the same time points were noted only in retrospect. A follow-up MRI at 2 months was normal. CONCLUSIONS: Ischemia from cerebral emboli may cause transient global amnesia precipitated by cerebral angiography. Diffusion-weighted MRI may be useful in defining the pathophysiology. PMID- 9368580 TI - Incomplete infarct and delayed neuronal death after transient middle cerebral artery occlusion in rats. AB - BACKGROUND AND PURPOSE: The clinical syndrome of transient ischemic attacks is accompanied in a significant percentage of patients by brain lesions or neuroimaging abnormalities whose structural counterparts have not been defined. The objective of this study was to analyze, in an experimental model of short term (< 25 minutes) focal ischemia and long-term (< or = 28 days) reperfusion, the extent and nature of the structural abnormalities affecting neurons and glia located within the territory of the transiently occluded artery. METHODS: Adult Wistar rats (n = 121) had the origin of one middle cerebral artery (MCA) occluded with a nylon monofilament for periods of 10 to 25 minutes. Experiments of transient MCA occlusion were terminated at variable periods ranging from 1 day to 4 weeks. Control experiments consisted of (1) MCA occlusion without reperfusion (n = 7) lasting 7 to 14 days and (2) sham operations (n = 2) followed by 1- to 4 day survival. After in situ fixation, brain specimens were serially sectioned and subjected to detailed morphometric evaluations utilizing light and electron microscopes. The statistical method used to evaluate the results was based on ANOVA followed by Bonferroni's corrected t test and Student's t test comparisons. RESULTS: Brain lesions were not detectable in the sham-operated controls. All brains with permanent MCA occlusion (7 to 14 days) had large infarctions with abundant macrophage infiltration and early cavitation. Forty-five (37%) of the experiments involving transient MCA occlusion had no detectable brain lesions after 4 weeks. Selective neuronal necrosis was found in 76 of 121 rats (63%) with transient MCA occlusion. Neuronal necrosis always involved the striatum, and in 29% of the brains with ischemic injury, necrosis also included a short segment of the cortex. In the striatum, the length of the arterial occlusion was the main determinant of the number of necrotic neurons (20 minutes [22.6 +/- 19] is worse than 10 minutes [4.9 +/- 7]) (P < .0001). In the cortex, the length of reperfusion determined the number of necrotic neurons appearing in layer 3. Experiments with reperfusion of 4 to 7 days' duration yielded more necrotic neurons per microscopic field (2.02 +/- 3) than those lasting fewer days (0.04 +/ 0.1) (P < .05). The histological features of these lesions underwent continuous change until the end of the fourth week, at which time necrotic neurons were still visible both in the striatum and in the cortex. CONCLUSIONS: Arterial occlusions of short duration (< 25 minutes) produced, in 76 of 121 experiments (63%), brain lesions characterized by selective neuronal necrosis and various glial responses (or incomplete infarction). This lesion is entirely different from the pannecrosis/cavitation typical of an infarction that appears 3 to 4 days after a prolonged arterial occlusion. Delayed neuronal necrosis, secondary to a transient arterial occlusion or increasing numbers of necrotic neurons in experiments with variable periods of reperfusion, was a response observed only at a predictable segment of the frontoparietal cortex. PMID- 9368582 TI - Vascular effects of statins in stroke. AB - BACKGROUND: Recent clinical trials and meta-analyses of beta-hydroxy-beta methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have demonstrated a reduction in ischemic stroke in patients with a history of coronary artery disease both with and without elevations of serum cholesterol. This review summarizes clinical trials of these compounds and their recent impact on stroke and explores the underlying vascular mechanisms of their actions. SUMMARY OF REVIEW: Use of statins in patients with vascular disease has been shown to lower the incidence of stroke by approximately 30%. Statins exhibit a number of antiatherosclerotic and antithrombotic properties that likely underlie the recently observed reductions in cerebrovascular disease. Statins reduce inflammatory, proliferative, and thrombogenic processes in plaque, making it less likely to rupture. Additionally, they reverse the endothelial dysfunction and platelet activation accompanying hypercholesterolemia and may reduce the tendency to thrombosis. CONCLUSIONS: Hypercholesterolemia has reemerged as a risk factor for ischemic stroke. Statins protect against thromboembolic stroke through multiple beneficial effects within the vascular milieu. Further data are awaited to support the growing importance of cholesterol as a risk factor for ischemic stroke and the benefits of statin therapy in patients with cerebrovascular disease. PMID- 9368583 TI - Pathological laughter and crying in unilateral stroke. PMID- 9368584 TI - Treatment of poststroke pathological crying. PMID- 9368585 TI - Postprandial cerebral ischemia. PMID- 9368586 TI - Internal and external carotid contributions to near-infrared spectroscopy during carotid endarterectomy. PMID- 9368587 TI - Ischemic stroke due to calcific emboli from mitral valve annulus calcification. PMID- 9368588 TI - The pathology of asthma. AB - Asthmatics respond with reversible airway narrowing when stimulated in ways that have no effect on non-asthmatic persons. Studies conducted at the turn of this century established that the pathology present in the airways of asthmatics is based on the inflammatory process. Recent work suggests that this inflammatory response may be driven by a particular group of T cells (Th2 response) that cause an overproduction of IL-4, IL-5 and other cytokines that produce an excessive infiltration of eosinophils and overproduction of IgE. The structural changes produced by the inflammatory process result in an overall thickening of the airway wall with changes in the epithelium, an increase in the interstitial matrix particularly the collagen types that contribute to the light microscopic appearance of the basement membrane, the vasculature, smooth muscle and mucous glands. Contraction of airway smooth muscle results in narrowing of the lumen particularly in the bronchioles where smooth muscle surrounds the entire lumen. An increase in wall tissue thickness as a result of asthma amplifies this normal effect producing a greater reduction in the airway lumen. Computer modelling of airway function and direct measurement of airway resistance in patients suggest that the smaller airways are the site of the greatest increase in airway resistance in asthma. These new data have shifted the emphasis away from the concept that abnormal airway smooth muscle function causes asthma toward the hypothesis that inflammatory-based changes in the airway wall act in series with normal smooth shortening to produce disease. The increased understanding of the role of the inflammatory process provides a basis for treatment of asthma with anti-inflammatory agents. PMID- 9368589 TI - The histopathology of human gastric mucosa inhabited by Helicobacter heilmannii like (Gastrospirillum hominis) organisms, including the first culturable case. AB - The aim was to determine the prevalence of Helicobacter heilmannii-like organisms in human gastric biopsies and the associated histology compared with that of Helicobacter pylori-bearing gastric biopsies. Furthermore, the feasibility of culturing H. heilmannii was examined. A consecutive series of 727 gastric biopsies from 650 patients were prospectively scrutinized for H. heilmannii. Their distribution pattern was recorded as well as the affiliated morphology of the gastric mucosa. Additional biopsies from some of the patients were examined microbiologically. Four cases (0.6%)(95% confidence intervals: 0.01-1.2%) of the examined material harboured H. heilmannii. The bacterial burden was graded as sparse in three cases, moderate in one case. The distribution pattern was patchy; thus, in no case did all biopsies from one endoscopy comprise H. heilmannii. Adhesion to epithelial cells was infrequent. A mild gastritis, active in three cases, characterized all biopsies. Lymphoid aggregates occurred in biopsies from three patients. Micropapillary tufting of the epithelial layer and intestinal metaplasia were not apparent. Culture studies proved successful in the one of the four cases assayed. In conclusion the morphology of H. heilmannii-bearing mucosa deviates from that of H. pylori-associated mucosa by the absence of epithelial damage in the former. This observation can in part be explained by the predominant location of H. heilmannii at a distance from the epithelium in contrast to the conspicuous H. pylori adhesion to epithelial cells, coupled with a usually low bacterial burden and patchy occurrence of H. heilmannii as opposed to the generally more heavy infestation with H. pylori. PMID- 9368590 TI - Immunohistochemical detection of p53 in archival formalin-fixed tissues of lip and intraoral squamous cell carcinomas from Norway. AB - We investigated the expression of p53 in 82 formalin-fixed, paraffin-embedded archival tissue specimens of lip and intraoral squamous cell carcinomas (SCCs) from the period 1930-1995, by immunohistochemistry using three monoclonal antibodies (MAbs DO-7, DO-1 and 1801). Before incubation, sections were pretreated with 0.1% Protease enzyme at 37 degrees C for 10 min followed by 5 + 5 min microwave oven heating at 700 W and 425 W, respectively. Formalin-fixed tissues of 10 carcinomas of the uterine cervix positive for p53 were used as controls. With one or more of the three MAbs, p53 was expressed in 73% of the 82 SCCs examined. With only protease enzyme pretreatment or microwave oven heating, p53 was expressed in 9/82 and 12/82 of the SCCs, respectively. Of the 82 SCCs, 60%, 45% and 23% expressed p53 with DO-7, DO-1 and 1801, respectively. The kappa coefficient indicated poor agreement between these results for the antibodies, and for lip and intraoral SCCs, except for p53 expression in intraoral SCCs demonstrated by DO-1/1801, which showed fair agreement. The present study suggests that combined protease pretreatment and microwave oven heating of tissue sections improved unmasking of p53 antigenic sites in archival material stored for up to 65 years. PMID- 9368591 TI - Association between p53 overexpression, cell proliferation, tumor necrosis and extent of apoptosis in operated pancreatic adenocarcinoma. AB - In this study we investigated the immunohistochemical expression of the p53 protein in 44 ductal pancreatic adenocarcinomas and its relation to cell proliferation, apoptosis and necrosis, three factors affecting tumor growth. The results were evaluated against survival and other clinical parameters of the patients. p53-positivity was found in 18/44 (41%) of the tumors. A positive p53 status was significantly associated with a high extent of necrosis (> or = 10% of tumor tissue)(p = 0.04, Fisher's exact test), with a high immunohistochemical expression of PCNA (p = 0.04, Fisher's exact test) and with a high mitotic count (p = 0.05, two-tailed t test). No statistically significant association was found between p53-positivity and high or low extent of apoptosis as evaluated by in situ labeling of the 3'-ends of the DNA fragments (p = 0.34, Fisher's exact test). Patient survival was not associated with the p53 expression of the tumors or separately with tumor cell proliferation, apoptosis or necrosis. The results suggest that an altered p53 function, as reflected by p53 overexpression, affects tumor growth by promoting cell proliferation and necrosis, but does not show a significant association with the extent of apoptosis in operated pancreatic adenocarcinoma. PMID- 9368593 TI - Hyperplastic foveolar gastropathies and hyperplastic foveolar gastritis. AB - Thirteen gastrectomy specimens having diffuse (n = 5), focal (i.e., nodular, n = 6) or combined (n = 2) giant hypertrophic folds at gross examination were reviewed. Of the five specimens with grossly diffuse hypertrophic fundic mucosal folds, two had at histology tortuous foveolar hyperplasia (without intraepithelial lymphocytosis) and prominent glandular cysts; they were classified as Menetrier's gastropathy. The other three specimens with diffuse foveolar hyperplasia had serrated foveolar infoldings with marked intraepithelial lymphocytosis; they were classified as Menetrier-like lymphocytic gastritis. Of the six, specimens with multiple mucosal nodules at gross examination, four had focal foveolar hyperplasia with crest depression and no intraepithelial lymphocytosis; they were classified as varioliform gastropathy. The other two specimens with multiple nodules at gross examination had focal foveolar hyperplasia with marked intraepithelial lymphocytosis; they were classified as varioliform gastritis. In the remaining two cases, both diffuse and nodular hypertrophic gastric mucosa were found at gross examination; at histology, both foveolar hyperplasia and intraepithelial lymphocytosis were found. The diffuse or focal distribution of the lesions, the occurrence of intraepithelial lymphocytosis and the architecture of the upper part of the crypts (in diffuse foveolar hyperplasias) were valuable criteria in the differential diagnosis between the various types of foveolar hyperplasia of the stomach. PMID- 9368592 TI - Induction of hepatic egg granuloma hyporesponsiveness in murine schistosomiasis mansoni by intravenous injection of small doses of soluble egg antigen. AB - This work was designed to test whether hyporesponsiveness to schistosomal egg antigen (SEA) was associated with reduction in size of hepatic granulomas. Multiple small doses of SEA (10 micrograms x 4) were injected intravenously (i.v.) into C57B1/6 mice either at 7 or 30 days prior to cercarial exposure. Eight weeks postinfection, hepatic histopathology and granuloma diameter were studied. SEA-induced lympho-proliferative response, splenic cytokines (IL-2, IL-4 and IL-5) and serum antischistosomal IgG were assessed. Worm burden and tissue egg load were counted. Compared to infected controls, the SEA-treated groups showed decrease in granuloma diameter, remarkable increase in the percentage of degenerated ova within hepatic granulomas and amelioration of histopathological changes. SEA lymphoproliferative response, and levels of Il-2 and IL-4, were lower in SEA-treated groups than infected controls. The levels of IL-5 and antishistosomal IgG were comparable to the infected controls. The intensity of infection was not influenced by i.v. injection of SEA. The present data show that i.v. administration of multiple small doses of SEA induced granulomatous hyporesponsiveness with amelioration of hepatic pathology and acceleration of egg destruction. PMID- 9368594 TI - Expression of myogenic marker proteins in human leiomyosarcoma. AB - A series of formalin-fixed, paraffin-embedded leiomyosarcomas (n = 11) was studied immunohistochemically for their expression of various myogenic marker proteins. According to their predominant histological appearance, the tumors were classified as well (n = 4), moderately (n = 5), or poorly (n = 2) differentiated. Using monoclonal anti-muscle specific actin antibodies from clone HHF35 all examined tumors were positively stained. Desmin was not always found in leiomyosarcomas, since positive staining could be demonstrated only in eight cases. As revealed by staining with anti-vinculin antibodies from clone hVIN-1 using the APAAP technique, all leiomyosarcomas with the exception of one expressed vinculin. Typically, the vinculin immunoreactivity was detected diffusely throughout the majority of neoplastic cells as well as in vascular smooth muscle cells of blood vessels. Nine leiomyosarcomas displayed a positive staining for calponin, an actin-binding protein expressed in smooth muscle cells and their precursors. The distribution of calponin resembled that of vinculin in decorating myofibrils of nearly all tumor cells. Actinin immunoreactivity was present in tumor cells of all cases, but was expressed also in nontumor cells such as epithelia. These results suggest that the monoclonal antibodies against vinculin and calponin may serve as additional diagnostic markers for myogenic differentiation in leiomyosarcomas and related tumors. PMID- 9368595 TI - Infrared imaging of human brain sections. A new biomedical application of the thermocamera. AB - Human brains, removed at routine autopsy, were subjected to neuropathological investigation. The usual gross morphological investigation of the brains was extended to include the detection of their infrared emissions. Fundamental structures, such as the grey and the white matter, were separated on the infrared images. Furthermore, pathological processes, such as ischaemic damage, haemorrhage, and sclerotic plaques, hardly seen on the normal photographs, gave a strong signal on the infrared pictures. These pilot experiments demonstrated that infrared detection is a reproducible method in this type of biomedical application, and potentially a very useful tool in macroscopic pathology. PMID- 9368596 TI - The 1995 list. Proposed new bacterial taxa and proposed changes of bacterial names published during 1995 and considered to be of interest to medical or veterinary bacteriology. An informational note. PMID- 9368597 TI - The 1996 list. Proposed new bacterial taxa and proposed changes of bacterial names published during 1996 and considered to be of interest to medical or veterinary bacteriology. An informational note. PMID- 9368598 TI - Identification and analysis of a novel member of the ubiquitin family expressed in dendritic cells and mature B cells. AB - Using a cDNA subtraction technique, a novel member of the ubiquitin family was isolated from human dendritic cells. This gene encodes a diubiquitin protein containing tandem head to tail ubiquitin-like domains, with the conservation of key functional residues. Expression of this 777-bp mRNA was restricted to dendritic cells and B cells, with strong expression in mature B cells. Southern blot analysis indicated that a single copy of this gene is present. In situ hybridization on tonsillar tissue showed expression in epithelial cells and isolated cells within the germinal center. With respect to an expressed-sequence tag (EST) this cDNA could be localized to the major histocompatibility complex class I region of chromosome 6. Comparative analysis and the expression pattern of this gene suggests a function in antigen processing and presentation. PMID- 9368599 TI - Biochemical characterization of the human diabetes-associated HLA-DQ8 allelic product: similarity to the major histocompatibility complex class II I-A(g)7 protein of non-obese diabetic mice. AB - The human HLA-DQ8 (A1*0301/B1*0302) allelic product manifests a strong association with insulin-dependent diabetes mellitus (IDDM). Previous biochemical studies of the major histocompatibility complex (MHC) class II I-A(g)7 protein of IDDM-prone non-obese diabetic mice produced controversial results. To better define the biochemical properties of IDDM-associated MHC class II molecules, we analyzed DQ8 proteins, in comparison to other DQ allelic products, by partially denaturing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We now report that DQ8 proteins have a normal peptide occupancy and lifespan in cells. Similar to I-A(g)7, DQ8 proteins formed only a minor fraction of SDS stable complexes with peptides. Although this phenotype was not unique to DQ8, some DQ allelic products such as IDDM-protective DQ6 proteins were SDS resistant. The DQ9 allelic product, differing from DQ8 only at position (P) beta 57, was SDS stable, suggesting that non-Asp residues at beta 57 might decrease the SDS stability of DQ proteins. We identified a single peptide which specifically induced an SDS-stable conformation in DQ8 as well as in I-A(g)7 molecules. The residues at anchor P1 in this peptide were found to influence the SDS stability of both molecules. Together with our previous observation of similar binding motifs of I-A(g)7 and DQ8, these results demonstrate an overall biochemical similarity of mouse and human diabetes-associated MHC class II molecules. This similarity might contribute to a common immunological mechanism of IDDM in both species. PMID- 9368600 TI - Chemotactic activity on mononuclear cells in the cerebrospinal fluid of patients with viral meningitis is mediated by interferon-gamma inducible protein-10 and monocyte chemotactic protein-1. AB - In viral meningitis the inflammatory response involves activated T cells and monocytes which are recruited into the subarachnoid space. To identify the chemotactic signals attracting the cells to the site of infection in the meninges, we measured the levels of two CXC chemokines, interferon-gamma (IFN gamma) inducible protein (IP)-10 and monokine induced by IFN-gamma, four CC chemokines, monocyte chemotactic protein (MCP)-1, RANTES, macrophage inflammatory protein (MIP)-1 alpha and MIP-1 beta, as well as the cytokines interleukin (IL) 15 and IL-16 in the cerebrospinal fluid (CSF) of patients suffering from viral meningitis. The results point to an involvement of two chemokines, MCP-1 and IP 10, since (1) unlike the other cytokines, MCP-1 and IP-10 were present in 97% and 79% of the CSF, respectively, at concentrations sufficient to induce chemotaxis of mononuclear cells; (2) more than 90% of the CSF of viral meningitis induced chemotaxis of peripheral blood mononuclear cells (PBMC) and all of them induced chemotaxis of activated T cells, and (3) the CSF-mediated chemotaxis of PBMC was inhibited by anti-MCP-1 antibodies and chemotaxis of activated T cells was abolished by the combination of anti-MCP-1 and anti-IP-10 antibodies. Our data provide evidence that MCP-1 and IP-10 lead to accumulation of activated T cells and monocytes in the CSF compartment in viral meningitis. PMID- 9368601 TI - Anterior chamber inoculation of splenocytes without Fas/Fas-ligand interaction primes for a delayed-type hypersensitivity response rather than inducing anterior chamber-associated immune deviation. AB - The inoculation of antigens into the anterior chamber (AC) of the eye induces an antigen-specific immune response that inhibits delayed-type hypersensitivity (DTH). This regulatory response is known as anterior chamber-associated immune deviation (ACAID). The ACAID response appears to be complex, as it can be elicited by a wide variety of soluble and cell-associated antigens, including foreign, self, tumor, and alloantigens. To evaluate the contribution of Fas/Fas ligand (FasL) interaction to the induction of ACAID to alloantigens, gld and lpr mutant mice were used in conjunction with normal C3H, MRL, and BALB/c mice. ACAID was induced by inoculation of non-irradiated splenocytes from donor mice into the AC of various recipients. After 1 week, recipients were primed intradermally with donor splenocytes. One week later DTH was measured by ear swelling. C3Hgld mutants lacking functional FasL did not develop ACAID after the AC inoculation of BALB/c splenocytes. Conversely, the AC inoculation sensitized these mutants. MRL/pr mutants, which lack Fas, developed ACAID following inoculation of BALB/c cells. AC inoculation of lpr splenocytes did not induce ACAID, but sensitized C3H recipients. Treatment of the AC inoculum with an anti-Fas antibody blocked ACAID induction in a transient manner, as the recipients developed ACAID later. These results show that interaction of the Fas and FasL is required to induce ACAID to allogeneic cells. In the absence of Fas expression on donor splenocytes, or FasL expression by the recipient, AC inoculation primes for a DTH response rather than inducing ACAID. PMID- 9368602 TI - Ligation of the T cell co-stimulatory receptor CD28 activates the serine threonine protein kinase protein kinase B. AB - The intracellular signaling pathways activated upon ligation of the co stimulatory receptor CD28 remain relatively ill-defined, although CD28 ligation does result in the strong association with, and activation of, phosphatidylinositol (PI) 3-kinase. The downstream effector targets of the CD28 activated PI 3-kinase-dependent signaling pathway remain poorly defined, but recent evidence from other systems has shown that Akt/protein kinase B (PKB) is a major target of PI 3-kinase and have indicated that a major function of PKB is the regulation of cell survival events. Given the strong coupling of CD28 to PI 3 kinase and the known protective effects of both CD28 and PI 3-kinase against apoptosis in different cell models, we investigated the effects of CD28 on PKB activation. We demonstrate that ligation of CD28 by either anti-CD28 monoclonal antibodies or the natural ligand B7.1, results in the marked activation of PKB in both the leukemic T cell line Jurkat and freshly isolated human peripheral blood derived normal T lymphocytes. Our data suggest therefore, that PKB may be an important intracellular signal involved in CD28 signal transduction and demonstrate CD28 coupling to downstream elements of a signaling cascade known to promote cell survival. PMID- 9368603 TI - Plasmodium falciparum sporozoite invasion is inhibited by naturally acquired or experimentally induced polyclonal antibodies to the STARP antigen. AB - Antibody(Ab)-mediated inhibition of sporozoite invasion of hepatocytes is a mechanism that has been clearly demonstrated to act upon Plasmodium falciparum pre-erythrocytic stages in humans. Consequently we have analyzed the Ab response to a recently identified P. falciparum sporozoite surface protein, STARP, in malaria-exposed individuals and tested the inhibitory effect of these Ab upon hepatocyte invasion in vitro. STARP-specific IgG were detected in 90 and 61% of sera from regions where individuals were exposed to 100 and 1-5 infectious bites per year, respectively. These IgG were predominantly of the cytophilic IgG1 or IgG3 type. STARP and the major sporozoite surface protein, CS, elicited equivalent IgG levels in adults. When affinity purified from either African immune sera or the serum of an individual experimentally protected by irradiated sporozoite immunization, STARP-specific Ab prevented up to 90% of sporozoites from invading human hepatocytes. The dose-dependent and reproducible inhibition was more pronounced than that observed with human CS-specific Ab affinity purified under identical conditions. Substantial reduction of sporozoite invasion was also observed with Ab induced by artificial immunization with recombinant STARP protein and reactive with the native protein. Taken together with recent findings of human cytotoxic T lymphocytes specific for this antigen, these results promote the interest of studying the efficacy of STARP as a target for immune effector mechanisms operating upon pre-erythrocytic stages. PMID- 9368604 TI - Neutrophil Fc gamma and complement receptors involved in binding soluble IgG immune complexes and in specific granule release induced by soluble IgG immune complexes. AB - We examined the effect of soluble IgG immune complex (IC) characteristics on the binding of IC to human neutrophils and IC-induced specific granule release of neutrophils via Fc gamma receptors (CD16 and CD32) and complement receptors (CR1 and CR3). A set of soluble IgG IC varying in size, IgG subclass, antigen epitope density and complement (C) incorporation were formed between 5-iodo-4-hydroxy-3 nitrophenacetyl (NIP) coupled to bovine serum albumin (BSA) and chimeric mouse human anti-NIP monoclonal antibodies (mAb) of all four IgG subclasses. High and low epitope density IC of all four IgG subclasses induced specific granule release with C, but in the absence of C only IgG1 and IgG3 IC were functionally active. The Fc gamma and C receptors responsible for IgG IC-induced specific granule release and IC binding were determined using mAb specific for the ligand binding sites of CD16, CD32 and CR3, and recombinant soluble CR1. Each defined IC displayed a unique pattern of receptor preference, dependent upon subclass and antigenic epitope density. IC binding and IC-induced specific granule release was not mediated by the same receptor, or combination of receptors. High and low epitope density IgG3 IC binding and induction of specific granule release was mediated predominantly via CD16. Other IC subclasses bound differently, i.e. IgG1 IC used CD16 and CR3; IgG2 and IgG4 predominantly used complement receptors; but all three induced specific granule release via CD32. In vivo these results may translate into differential activation of neutrophils by soluble IC dependent upon their characteristics, leading to subtle nuances in the etiology, pathology and control of the immune response in IC-related diseases. PMID- 9368605 TI - Homotypic interaction of the heat-stable antigen is not responsible for its co stimulatory activity for T cell clonal expansion. AB - The heat-stable antigen (HSA) is an important co-stimulatory molecule on antigen presenting cells (APC). However, the receptor on T cells that receives the co stimulatory signal from HSA has not been identified. Because the HSA is transiently expressed on T cells after the T cell receptor/CD3 complex is engaged, and because it can bind to itself in a homotypic fashion, it has been proposed that homotypic interaction of HSA is responsible for its co-stimulatory activity. Here we test this hypothesis using mice that have a targeted mutation of the HSA gene, as well as novel transgenic mice that constitutively express HSA on T cells. We show that HSA-deficient T cells remain responsive to co stimulation by HSA. Furthermore, constitutive expression of HSA does not enhance T cell response to co-stimulatory by HSA. Taken together, our results demonstrate that homotypic interaction of HSA is not responsible for co-stimulation mediated by HSA expressed on APC. PMID- 9368606 TI - Zinc inhibits interleukin-1-dependent T cell stimulation. AB - Zinc is a trace element which is essential for immune functions. It directly induces monokine secretion by monocytes; however, effects of zinc on T cells appear contradictory. Apart from enhanced lymphocyte proliferation in peripheral blood mononuclear cells (PBMC), inhibitory properties of high zinc dosages have also been described. In this study, PBMC failed to produce lymphokines like interferon (IFN)-gamma after stimulation with zinc in a serum- and LPS-free cell culture system, whereas monokine secretion [interleukin (IL)-1 beta] occurred. Zinc-uptake studies with the zinc-specific fluorescent probe zinquin revealed that zinc is taken up by PBMC within a few minutes, reaching nearly equal levels in PBMC, isolated monocytes, and T cells. However, if zinc was depleted 1 h after monocyte induction, zinc-free pre-cultured T cells were stimulated to secrete IFN gamma by zinc-induced monokines. Furthermore, the necessity for a cell-cell interaction between monocytes and T cells for IFN-gamma induction was elucidated. Zinc ions inhibited the proliferation of the IL-1-dependent T cell line D 10N in a dose-dependent manner, suggesting a direct inhibitory effect of zinc. By immunoprecipitation we revealed a specific inhibition of IL-1 receptor-associated protein kinase (IRAK) by zinc ions. Therefore, in contrast to an indirect stimulation of T cells due to zinc-induced monokines, higher concentrations of zinc directly inhibit T cell functions by means of specific inhibition of IRAK and subsequent signaling events such as NF kappa B activation. The divergent effects of zinc on different cell populations, depending on the zinc concentration, could explain contradictory results of zinc stimulation. Furthermore, our data suggest new strategies of specific zinc-mediated immune modulation. PMID- 9368607 TI - Interleukin-9 is involved in host protective immunity to intestinal nematode infection. AB - Murine studies have demonstrated that, as with other nematodes, infection with the intestinal nematode Trichinella spiralis is associated with a pronounced intestinal mastocytosis, eosinophilia and an elevation in serum levels of total IgE. Both interleukin (IL)-4 and IL-5 are clearly important in the generation of IgE responses and eosinophilia, respectively, but the control of mucosal mastocytosis in vivo is not as well defined. Mucosal mast cells appear to be particularly important with regard to T. spiralis infections as there is good evidence to suggest their involvement in expulsion of the parasite from the host. In this study we examined the effect of the overproduction of the Th2 cytokine IL 9 on infection with this nematode. We demonstrate that naive IL-9-transgenic mice have an intense intestinal mastocytosis and high serum levels of mouse mast cell protease-1. Moreover, upon infection high titers of parasite-specific IgG1 were observed with a heightened mast cell response, which was associated with the rapid expulsion of T. spiralis from the gut. Furthermore, as depression of this mast cell response, using anti-c-kit antibodies, resulted in the inability of these mice to expel the parasite, this study clearly demonstrates an activity of IL-9 on mucosal mastocytosis and the host protective immune response in vivo. PMID- 9368608 TI - Trypanosoma cruzi infection does not impair major histocompatibility complex class I presentation of antigen to cytotoxic T lymphocytes. AB - Trypanosoma cruzi (T. cruzi), the etiological agent of Chagas' disease, lives free within the cytoplasm of infected host cells. This intracellular niche suggests that parasite antigens may be processed and presented on major histocompatibility complex (MHC) class I molecules for recognition by CD8+ T cells. However, the parasite persists indefinitely in the mammalian host, indicating its success at evading immune clearance. It has been shown that T. cruzi interferes with processing and presentation of antigenic peptides in the MHC class II pathway. This investigation sought to determine whether interference in MHC class I processing and presentation occurs with T. cruzi infection. Surface expression of MHC class I molecules was found to be unaffected or up regulated by T. cruzi infection in vitro. A model system employing a beta galactosidase (beta-gal)-specific murine cytotoxic T lymphocyte (CTL) line (0805B) showed: (i) in vitro infection of mouse peritoneal macrophages or J774 cells with T. cruzi did not inhibit MHC class I presentation of exogenous peptide (a nine-amino acid epitope of beta-gal) to the CTL line, (ii) in vitro infection of a beta-gal-expressing 3T3 cell line (LZEJ) with T. cruzi did not inhibit MHC class I presentation of the endogenous protein to the CTL line and (iii) mouse renal adenocarcinoma cells infected with T. cruzi and subsequently infected with adenovirus expressing beta-gal were able to present antigen to the beta-gal specific CTL line. These findings indicate that the failure of the immune response to clear T. cruzi does not result from global interference by the parasite with MHC class I processing and presentation. Parasites engineered to express beta-gal were unable to sensitize infected antigen-presenting cells in vitro to lysis by the CTL 0805B line. This was probably due to the intracellular localization of the beta-gal within the parasite and its inaccessibility to the host cell cytoplasm. PMID- 9368609 TI - Normal macrophage functions, but impaired induction of gamma delta T cells, at the site of bacterial infection in CD45 exon 6-deficient mice. AB - We investigated the protective functions of macrophages and gamma delta T cells in adult CD45 exon 6-deficient (CD45 -/-) mice against an intraperitoneal (i.p.) infection with Listeria monocytogenes. gamma delta T cells are preferentially localized in the spleen, liver, and intraperitoneal cavity of the adult CD45-/- mice. Increased numbers of gamma delta T cells were observed after i.p. infection with L. monocytogenes in the peritoneal cavity of C57BL/6 (CD45 +/+) mice but not in CD45 -/- mice. The gamma delta T cells showed predominant usage of V delta 5 and V delta 6 rearranged to J delta 1 in the infected CD45 -/- mice which are the same as those used by resident gamma delta T cells of noninfected CD45 +/+ and CD45 -/- mice. Furthermore, we analyzed the protective abilities of the CD45 -/-, CD45 +/+, and gamma delta T cell-depleted mice at the early stage of the listerial infection. The numbers of bacteria in the spleens and livers of the CD45 -/- mice 5 days after the listerial infection were almost ten times larger than those in the CD45 -/- and gamma delta T cell-depleted CD45 +/+ mice. Macrophages showed normal antigen presentation, nitric oxide production and bactericidal activity for L. monocytogenes despite their lacking CD45 surface expression, suggesting that CD45-negative macrophages have a minimal influence on the increased bacterial multiplication in the CD45-/- mice. These results suggest that the gamma delta T cells are induced by the bacterial infection in a CD45 dependent manner, and that unresponsiveness of the gamma delta T cells results in only weak protection against L. monocytogenes in CD45 -/- mice. PMID- 9368610 TI - The mast cell function-associated antigen exhibits saccharide binding capacity. AB - The mast cell function-associated antigen (MAFA) is a membrane glycoprotein first identified on rat mucosal type mast cells (line RBL-2H3) and known to inhibit the Fc epsilon RI-mediated secretory response. In its extracellular domain, an amino acid stretch homologous to the carbohydrate binding domain of calcium-dependent animal lectins has been found. To investigate its carbohydrate binding capacity, the MAFA has been expressed in the Spodoptera frugiperda insect cell line (Sf9) using the baculovirus expression system. Analysis by flow cytometry and surface labeling with 125I showed that the recombinant MAFA (rMAFA) was expressed as a monomeric and disulfide-linked homodimeric glycoprotein in the membrane of the insect cells, and both forms exhibited the same epitopes as the protein isolated from RBL-2H3 cells. Immunoaffinity-purified rMAFA was then employed for studies of its saccharide binding capacity by using different neoglycans and glycoproteins. The rMAFA was found to bind specifically terminal mannose residues in a Ca(2+)-dependent manner. These results support the notion that the extracellular domain of the MAFA is indeed able to bind ligands, which may be modulatory for the mast cell response. PMID- 9368611 TI - Induction of T cell adhesion to extracellular matrix or endothelial cell ligands by soluble or matrix-bound interleukin-7. AB - The putative effects of interleukin (IL)-7, operating in the context of extracellular matrix (ECM), on the adhesion of human T cells were examined. Recombinant human, IL-7 was found to bind ECM or fibronectin (FN) with IC50 values of 10-100 nM. Nanogram amounts of both soluble and, especially, FN- or ECM bound IL-7, which differentially affected the morphologies of FN-adherent T cells, induced the adhesion of resting CD4+ and CD8+ T cells in dose-dependent and beta 1 integrin-dependent manners. Under static and flow conditions, soluble IL-7 also induced the binding of unstimulated T cells to vascular cell adhesion molecule-1, suggesting that this cytokine can also modulate integrin binding to endothelial cell ligands. The effects of affinity modulation by IL-7 of FN specific beta 1 integrins depend on the presence of soluble FN, which inhibited T cell adhesion to FN induced by FN-bound IL-7 or by an integrin-specific affinity modulating monoclonal antibody, but not by soluble IL-7 or phorbol 12-myristate 13-acetate. These findings provide an example of a major ECM integrin ligand, FN, which is capable of modulating its adhesive interactions with specific immune cells by associating with and presenting a cytokine in a bio-active state. PMID- 9368612 TI - Chemoattractant receptor cross talk as a regulatory mechanism in leukocyte adhesion and migration. AB - Leukocytes express multiple chemoattractant receptors that can trigger adhesion and direct their migration. Regulation of such proadhesive and migratory responses must often occur in a complex cytokine milieu in vivo, in which multiple receptors may be engaged simultaneously or sequentially, Here we have examined the interplay between interleukin-8 (IL-8) receptor and formyl peptide receptor (fPR)-stimulation and its consequences for leukocyte adhesion and chemotactic responses. IL-8 has no significant effect on fMLP-stimulated adhesion and migration of human neutrophils, indicating that leukocytes have the potential to respond to sequential proadhesive and chemoattractant stimuli during homing and targeted migration. In contrast, fMLP at > or = 10 nM totally abrogated proadhesive and chemoattractant responses to IL-8, a trnas effect to which the fPR itself is relatively resistant. N-formyl peptides are released by invasive bacteria and lysed cells, and the dominance of the fPR may ensure that signals from these terminal phagocyte targets can override host-derived recruitment signaling through IL-8 and other chemokine receptors. Asymmetric inhibition of adhesion-triggering responses is also observed in lymphoid cells transfected with IL-8 receptor A and fPR, but in this cellular context chemotactic responses are bidirectionally abrogated, suggesting the potential for downstream desensitization of motility programs as well. Cross talk between chemoattractant receptors and their signaling pathways may help target leukocyte migration in the context of complex chemoattractant arrays in vivo. PMID- 9368613 TI - MUC1 peptide epitopes associated with five different H-2 class I molecules. AB - We have previously described the induction of murine CD8+ major histocompatibility complex (MHC) class I-restricted cytotoxic T cells (CTL) recognizing the 20-amino acid repeat region of the human mucin 1 (MUC1) variable number of tandem repeats region (VNTR), a mucin greatly increased in expression in breast cancer and proposed as a target for immunotherapy. In that study, CTL could detect MUC1 peptides associated with the MHC of all nine strains examined, and we now report the different epitopes presented by five different MHC class I molecules. The epitopes were defined in CTL assays using peptide-pulsed phytohemagglutinin blasts or MHC class I-transfected L cells as targets; in addition, peptide binding assays and T cell proliferation studies were performed. Within the 20-amino acid VNTR, nine potential epitopes could be defined. The epitopes for the four MHC class I molecules [Kb (three epitopes), Dd, Ld and Kk] were closely related, all containing the amino acids PDTRPAP. For Db, three epitopes were identified, all containing APGSTAP. Most of the epitopes did not contain a consensus motif for the particular MHC class I allele, and bound with low 'affinity', compared with known high-affinity peptides. CD8+ T cell proliferation also occurred to the same MHC class I-presented epitopes. Finally, when conventional anchor residues were introduced into the peptides, peptide binding increased, whereas CTL recognition was either retained (Kb) or lost (Db) depending on the epitope. PMID- 9368614 TI - A murine transmembrane tumor necrosis factor (TNF) transgene induces arthritis by cooperative p55/p75 TNF receptor signaling. AB - The arthritogenic activities of tumor necrosis factor (TNF) and its p55TNF receptor (R) have been well documented in experimental animal models of arthritis, and in transgenic mice expressing wild-type or mutant transmembrane human TNF proteins in their joints. In this study we show that chronic inflammatory arthritis also develops in transgenic mice made to overexpress a mutant transmembrane from of the murine TNF protein (muTNF delta 1-12) which is known to utilize efficiently both the p55 and the p75TNFR. Cross-breeding of the transgene into a TNF knockout background did not alter development of disease. Analysis of TNF bioactivity in sera from lipopolysaccharide-stimulated mice or ex vivo macrophage cultures demonstrated that the muTNF delta 1-12 protein accumulates on the cell surface and is not processed to bioactive soluble TNF, indicating that transmembrane TNF is by itself sufficient to mediate pathogenesis of arthritis. Furthermore, using TNFR knockout mice, it is shown that development of transmembrane TNF-mediated arthritis requires the presence of the p55TNFR but is significantly delayed in the absence of the p75TNFR, suggesting a positive cooperation between the two TNFR in the arthritogenic process. These results indicate that blocking the activities of both soluble and transmembrane TNF may be required to effectively neutralize the pathogenic potential of this cytokine in arthritis. PMID- 9368615 TI - Down-regulation of the major circulating precursors of proteins deposited in secondary amyloidosis by a recombinant mouse interleukin-1 receptor antagonist. AB - An inflammatory response was induced in C57BL/6 mice using silver nitrate. Co administration of a recombinant mouse interleukin-1 receptor antagonist (rmIL 1ra) significantly reduced the magnitude of hepatic induction of the mRNA specifying the serum amyloid A (A-SAA) isoforms A-SAA1 and A-SAA2 for up to 24 h. In relative terms, the amount by which the induction of serum A-SAA protein levels could be countered by the antagonist was less, probably reflecting extrahepatic A-SAA synthesis that is regulated independently of IL-1. Induction of hepatic serum amyloid P component (SAP) mRNA and other acute-phase reactant (APR) mRNA were all partially blocked by rmIL-1ra for up to 24 h, indicating that induction of these APR mRNA involves both IL-1 and additional factors acting independently of IL-1. Hepatic mRNA levels of the negative APR apolipoprotein A-I (apo A-I) and serum albumin were down-regulated by silver nitrate treatment; rmIL 1ra partially restored serum albumin mRNA levels but not those of apo A-I. The IL 1ra-mediated reduction in inflammation-induced hepatic mRNA and serum protein concentrations of A-SAA and SAP (the precursors of the main protein components of amyloid deposits in secondary amyloidosis) was, however, not sufficient to prevent or delay early amyloid deposition in the silver nitrate/amyloid enhancing factor model of accelerated amyloidosis. The rmIL-1ra may be a useful component in future therapies to control inflammation and secondary amyloidosis; in addition, it will be a useful tool for the detailed analysis of the IL-1-driven aspects of inflammation per se. PMID- 9368616 TI - Distinct roles for lymphotoxin-alpha and tumor necrosis factor in organogenesis and spatial organization of lymphoid tissue. AB - Specialized roles for the pro-inflammatory cytokines tumor necrosis factor (TNF) and lymphotoxin (LT) were characterized in TNF/LT alpha -/- and TNF -/- mice established by direct gene targeting of C57BL/6 ES cells. The requirement for LT early in lymphoid tissue organogenesis is shown to be distinct from the more subtle and varied role of TNF in promoting correct microarchitectural organization of leukocytes in LN and spleen. Development of normal Peyer's patch (PP) structure, in contrast, is substantially dependent on TNF. Only mice lacking LT exhibit retarded B cell maturation in vivo and serum immunoglobulin deficiencies. A temporal hierarchy in lymphoid tissue development can now be defined, with LT being an essential participant in general lymphoid tissue organogenesis, developmentally preceeding TNF that has a more varied and subtle role in promotion of correct spatial organization of leukocytes in LN and spleen PP development in TNF -/- mice is unusual, indicating that TNF is a more critical participant for this structure than it is for other lymphoid tissues. PMID- 9368617 TI - Microsites for immunoglobulin switch recombination breakpoints from Xenopus to mammals. AB - Immunoglobulin (Ig) heavy chain class switch recombination has been studied at the DNA level in a non-mammalian vertebrate, the amphibian Xenopus. A switch (S) region of about 5 kb has been identified in the JH-C mu intron of the Ig heavy chain locus in Xenopus. S mu contains 23 repeats approximately 150 bp long. Each repeat consists of internal shorter repeats and palindromic sequences, such as AGCT, which they share with mammalian switch regions. A deletion of the mu gene and the joining of the S regions of mu and chi occurs in B cells expressing IgX, one of the two non-mu isotypes in Xenopus. S chi shows no sequence homology with S mu and is characterized by 16 and 121 bp repeats and a high frequency of CATG, AGCA and TGCA palindromes. Both IgM and IgX S regions are AT rich and not GC rich like mammalian S regions. Recombination occurs, most of the time, at positions (microsites) where a single-stranded DNA folding program predicts the transition from a stem to a loop structure. This feature is conserved in most mammalian switch junctions which points to the general existence and involvement of microsites at one step of the determination of the recombination break-point. The recombinogenic nature of the switch regions is therefore linked to its structure rather than to its base composition, the repetitive occurrence of palindromes being essential at creating many microsites. PMID- 9368618 TI - Induction of anti-carbohydrate antibodies by phage library-selected peptide mimics. AB - One of the prerequisites for the development of polysaccharide subunit vaccines is the induction of an efficient immune response to carbohydrate antigens like lipopolysaccharide (LPS) or capsular polysaccharide antigens of pathogens. In an attempt to overcome the problems that arise from the T-independent immune response induced by such antigens, selecting peptide sequences that mimic protective carbohydrate epitopes has been proposed. In this study, we investigate a new selection strategy for immunogenic peptide mimics using the phage-displayed peptide library technology. Two monoclonal antibodies (mAb) of the A isotype (mIgA), mIgA C5 and mIgA I3, specific for the O-antigen (O-Ag) part of the human pathogen Shigella flexneri serotype 5a LPS and protective against homologous infection were used to screen two phage-displayed nonapeptide libraries in pVIII. Using mIgA C5, 13 different specific clones were selected, and 6 using mIgA I3; 5 of the latter also interacted in enzyme-linked immunosorbent assay with the first mAb. All of the 19 clones selected were separately used to immunize mice, but only 2 of them, p100c (mIgA I3-specific) and p115 (interacting with both mIgA) were able to induce anti-O-Ag antibodies. The immune response was specific for the O-Ag of the S. flexneri serotype 5a, and also selectively recognized the corresponding bacterial strain. The amino acid sequences of p100c and p115 immunogenic peptide mimics were YKPLGALTH (flanked by two Cys residues) and KVPPWARTA, respectively. These results are the first example of immunogenic mimicry of carbohydrates by phage-displayed peptides, and indicate a new strategy of selection of immunogens for the development of anti-polysaccharide vaccines. PMID- 9368619 TI - Crucial role of marginal zone macrophages and marginal zone metallophils in the clearance of lymphocytic choriomeningitis virus infection. AB - Macrophages play a key role in the immune defense against pathogens. They control early invasion by antigen-unspecific phagocytosis of pathogens and act as professional antigen-presenting cells to induce antigen-specific T cell responses. To investigate the involvement of particular subsets of the splenic macrophages in an antiviral immune response, we selectively depleted mice of splenic marginal zone macrophages (MZM) and marginal zone metallophils (MM) using the clodronate liposome depletion technique. MZM- and MM-depleted mice were not able to control an infection with lymphocytic choriomeningitis virus (LCMV). In these mice, LCMV spread from the spleen to peripheral organs at an early phase of infection. The virus-specific cytotoxic T lymphocyte (CTL) response was induced initially, yet was exhausted in parallel with the overwhelming virus replication. These findings suggest that MZM and MM play a crucial role in the early control of a LCMV infection by preventing immediate virus spread to peripheral organs, but are not essential for the induction of the LCMV-specific CTL response. PMID- 9368620 TI - A Leishmania protein that modulates interleukin (IL)-12, IL-10 and tumor necrosis factor-alpha production and expression of B7-1 in human monocyte-derived antigen presenting cells. AB - LeIF, a gene homologue of the eukaryotic initiation factor 4A was first described as a leishmanial antigen that induced a Th1-type T cell response in peripheral blood mononuclear cells (PBMC) from leishmaniasis patients. Moreover, the interferon (IFN)-gamma production by PBMC was found to be interleukin (IL)-12 dependent. Herein, we characterize the effects of LeIF on cytokine production and expression of surface molecules by normal human monocytes as well as by monocyte derived macrophages and dendritic cells (MoDC). LeIF was a strong inducer of IL 12 and, to a lesser extent, of IL-10 and tumor necrosis factor (TNF)-alpha in macrophages and MoDC. IL-12 production did not require CD40 triggering, confirming that the ability of LeIF to induce IL-12 was not mediated through an effect on T cells. However, addition of soluble CD40 ligand (L) synergistically augmented IL-12 production in macrophages and MoDC. The cytokine-inducing activity of LeIF is located in the N-terminal portion of the molecule and was both proteinase K sensitive and polymyxin B resistant. LeIF, lipopolysaccharide and fixed Staphylococcus aureus all induced comparable amounts of IL-12, validating the potent cytokine-inducing effects of LeIF. Moreover, of these stimuli, LeIF had the highest IL-12/IL-10 and IL-12/TNF-alpha ratio demonstrating the preference of LeIF for IL-12 induction. Studies investigating the expression of surface molecules showed that LeIF up-regulated B7-1 and CD54 (ICAM-1) on macrophages and MoDC. To our knowledge this is the first report describing IL-12 production, up-regulation of co-stimulatory and intercellular adhesion molecules by monocytic antigen-presenting cells in response to a protein from a pathogenic microorganism. These immunomodulatory characteristics of LeIF might be excellent properties for a Th1-type adjuvant. PMID- 9368621 TI - Co-localization of Fyn with CD3 complex, CD45 or CD28 depends on different mechanisms. AB - The Src family protein tyrosine kinase Fyn (p59fyn) plays an important role in thymocyte development and T cell receptor (TCR) signal transduction. Fyn has been shown to associate with the TCR-CD3 complex, the protein tyrosine phosphatase CD45 and several co-receptors such as CD28 which are crucial for initiating T cell activation and proliferation. The molecular basis of how Fyn is associated with these transmembrane proteins is largely unknown. To investigate the Fyn association with the TCR-CD3 complex, CD45 and CD28 at the molecular level, various Fyn/beta-galactosidase fusion proteins were constructed and expressed in Jurkat cells. Co-localization experiments applying antibody-induced co-capping and double immunofluorescence staining techniques were used to study the association of these fusion proteins with the TCR-CD3 complex, CD45 and CD28. Our results revealed that co-localization of Fyn with the TCR-CD3 complex requires the unique N terminus whereas co-localization with CD45 depends on the unique N terminus, the Src homology (SH)3- and a functional SH2 domain. CD28 co-localizes with Fyn molecules that contain the N terminus and a functional SH2 domain. These results suggest that Fyn association with the TCR-CD3 complex, CD45 and CD28 is mediated by different molecular mechanisms. PMID- 9368622 TI - Human recombinant interferon-beta influences T helper subset differentiation by regulating cytokine secretion pattern and expression of homing receptors. AB - Type I interferons (IFN) are important regulators of both innate and acquired immunity. We have used an in vitro system of human CD4+ T cell differentiation to determine how IFN-beta influences development of T helper (Th) subsets and homing receptor expression. IFN-beta promoted differentiation of CD4+ T cells that produce low levels of both IFN-gamma and lymphotoxin compared to interleukin (IL) 12-derived Th1 CD4+ T cells. IFN-beta inhibited production of Th2 cytokines (IL-5 and IL-13) and augmented IL-12-mediated IL-10 secretion. In addition, IFN-beta significantly enhanced L-selection expression on CD4+ T cells and synergized with IL-12 to induce expression of cutaneous lymphocyte-associated antigen (CLA). This Th1 L-selectin+, CLA+ phenotype is characteristic of T cells found in normal human skin and suggests a role for type I IFN in the regulation of Th subset differentiation and tissue-specific homing receptors. PMID- 9368623 TI - Antigen-specific CD8+ T cells inhibit IgE responses and interleukin-4 production by CD4+ T cells. AB - There is a growing body of evidence which suggests that CD8+ T cells play an important part in regulating the IgE response to non-replicating antigens. In this study we have systematically investigated their role in the regulation of IgE and of CD4+ T cell responses to ovalbumin (OVA) by CD8+ T cell depletion in vivo. Following intraperitoneal immunization with alum-precipitated OVA, OVA specific T cell responses were detected in the spleen and depletion of CD8+ T cells in vitro significantly enhanced the proliferative response to OVA. Depletion of CD8+ T cells in vivo 7 days after immunization failed to enhance IgE production, while depletion of CD8+ T cells on days 12-18 greatly enhanced the IgE response, which rose to 26 micrograms/ml following a second injection of anti CD8 on day 35 and remained in excess of 1 microgram/ml over 300 days afterwards. Reconstitution on day 21 of rats CD8-depleted on day 12 with purified CD8+ T cells from animals immunized on day 12 completely inhibited the IgE response. This effect was antigen specific; CD8+ T cells from OVA-primed animals had little effect on the IgE response of bovine serum albumin immunized rats. In vivo, CD8+ T cell depletion decreased interferon (IFN)-gamma production but enhanced interleukin (IL)-4 production by OVA-stimulated splenic CD4+ T cells. Furthermore, CD8+ T cell depletion and addition of anti-IFN-gamma antibody enhanced IgE production in vitro in an IL-4-supplemented mixed lymphocyte reaction. These data clearly show that antigen-specific CD8+ T cells inhibit IgE in the immune response to non-replicating antigens. The data indicate two possible mechanisms: first, CD8+ T cells have direct inhibitory effects on switching to IgE in B cells and second, they inhibit OVA-specific IL-4 production but enhance IFN-gamma production by CD4+ T cells. PMID- 9368624 TI - Secreted proteophosphoglycan of Leishmania mexicana amastigotes activates complement by triggering the mannan binding lectin pathway. AB - Cutaneous lesions induced by infection of mice with the protozoan parasite, Leishmania mexicana, contain abundant amounts of a high molecular mass proteophosphoglycan (PPG), which is secreted by the amastigote stage residing in phagolysosomes of macrophages and can then be released into the tissue upon rupture of the infected cells. Amastigote PPG forms sausage-shaped but soluble particles and belongs to a novel class of serine-rich proteins that are extensively O-glycosylated by phosphooligosaccharides capped by mannooligosaccharides. The purified molecule is shown here to efficiently activate complement (C) and deplete hemolytic activity of normal serum and may prevent the opsonization of L. mexicana amastigotes. Complement activation is Ca2+ dependent but does not depend on antibodies or the complement component C1. PPG binds to serum mannan binding protein (MBP), thus activating the MBP associated serine protease, P100. Subsequently, the C cascade is triggered through C4 leading to covalent modification probably of carbohydrate hydroxyls of PPG by C3 fragments. Thus, PPG is able to activate C via the mannan binding lectin pathway which is unusual for secreted, soluble products of microbial origin. The proteophosphoglycan-induced complement activation is postulated to contribute to the lesion development and pathology caused by the parasite. PMID- 9368626 TI - Ultrastructural analysis of mouse thymocyte subpopulations. AB - To understand the lineage relationship and to define morphological characteristics of each thymocyte subset, we have performed ultrastructural analysis of highly purified thymocyte subpopulations. By flow cytometry, five subpopulations were sorted based on the expression of CD4 and CD8 and on cell size (forward scatter): large and small CD4+8+, CD4-8-, CD4+8-, and CD4-8+ thymocytes. Small CD4+8+ thymocytes were the smallest among lymphoid cells, and had a round and smooth cell outline with condensed nuclei, the cytoplasm was scanty and the cell organelles were not developed, suggesting the majority of this subset might be inactive by morphological criteria. CD4+8- thymocytes appeared to be similar to peripheral CD4+ T cells. The CD4-8- thymocyte subset contained morphologically immature cells in terms of cell size, presence of cell surface villi, and euchromatic appearance of the nucleus. CD4-8+ thymocytes heterogeneous in cell size, nuclear chromatin contents and amount of cytoplasm, could be divided into two distinct types. Type 1 CD4-8+ thymocytes were intermediate in size, and therefore similar to peripheral mature CD8+ T cells. Type 2 CD4-8+ thymocytes were large and irregular in shape (large CD4-8+) with irregular-shaped and euchromatic nuclei. Large CD4-8+ cells were, thus, considered to be at the transitional stage from CD4-8- to CD4+8+. At least two groups of large CD4+8+ cells were ultrastructurally classified by the nuclear chromatin content. Large CD4+8+ cells with heterochromatic nuclei were round with a smooth cell membrane, whereas large CD4+8+ cells with euchromatic nuclei were spherical with projections. Cytological features of heterochromatic large CD4+8+ cells are similar to those of small CD4+8+ thymocytes except for cell size. Euchromatic large CD4+8+ cells could be regarded as active blasts potentially leading to mature cells. Taken together, this is the first report that describes the ultrastructural characteristics of each thymocyte subset highly purified by flow cytometry. PMID- 9368625 TI - Complement C3b fragment covalently linked to tetanus toxin increases lysosomal sodium dodecyl sulfate-stable HLA-DR dimer production. AB - Processing and presentation of covalently linked C3b-tetanus toxin (TT) complexes, as compared to unlinked C3b + TT, lead to increased T cell proliferation. The aim of this study was to analyze the effect of coupling C3b to TT on the efficiency of TT peptide loading on HLA-DR1 molecules. In the Epstein Barr virus-transformed B cell line HOM 2, we detected a significant increase of sodium dodecyl sulfate (SDS)-stable major histocompatibility complex (MHC) class II molecules after exposure to C3b-TT as compared to unlinked C3b and TT. The ratio of compact form/unbound form (C/U ratio) obtained with C3b-TT as antigen (Ag) is about twice that obtained with uncomplexed TT + C3b as Ag. Similar results were obtained using HLA-DR1-transfected fibroblasts that do not express C3b complement receptors, indicating that the SDS-stable HLA-DR1 increase did not result simply from C3b opsonization but rather from a direct effect of C3b-TT linkage on peptide generation. Exposure of HOM 2 cells to C3b-TT resulted in an increase in concentration of SDS-stable HLA-DR molecules in lysosomes but not in endosomes. Thus, C3b attachment to Ag induces a redistribution of peptide/MHC complex which results in a higher efficiency of Ag presentation by MHC class II molecules. PMID- 9368627 TI - Anti-adhesive signals are mediated via major histocompatibility complex class II molecules in normal and neoplastic human B cells: correlation with B cell differentiation stage. AB - We show that major histocompatibility complex (MHC) class II molecules on B cells transit signals which regulate adhesion in a negative manner. Engagement of MHC class II molecules with antibodies results in detachment of B cells previously bound to interferon-gamma-activated human umbilical cord venous endothelial cells. This process depends on metabolic energy, active signaling and protein tyrosine kinase activity. The adhesion pathway influenced by this signaling event is neuraminidase sensitive. The anti-adhesive signaling program is activated in B cell lines with a mature phenotype, e.g. normal B cells from spleen and tonsil. In contrast, cell lines with a pre-B cell phenotype and normal B cells from peripheral blood are refractory to MHC class II-mediated regulation of adhesion. These results extend to neoplastic cells from patients with lymphoproliferative diseases representing different stages of B cell maturation. These results suggest that MHC class II-mediated signals regulate B cell adhesion in a developmentally programmed fashion; this might have implications for clinical behavior of B cell malignancies. PMID- 9368628 TI - Interleukin-12 up-regulates the induction of an antigen-specific antibody response in cultures of human lymphocytes. AB - The influence of interleukin-12 (IL-12) on the induction of a specific antibody response to the T-dependent antigen sheep erythrocytes (SRBC) in cultures of human blood lymphocytes was investigated. The response, evaluated as number of antigen-induced antibody-producing cells, was greatly increased in the presence of IL-12. When a two-stage limiting dilution culture system was used, the plot of the number of seeded cells versus the logarithm of the fraction of negative cultures deviated from linearity in antigen- and IL-12-stimulated cultures. However, linearity was reached when IL-2 was added in the second stage. Under these latter conditions, since single-hit criteria were fulfilled, it was possible to estimate the frequency of SRBC-specific B cell precursors able to respond to the antigen and to show that such frequency was increased upon addition of IL-12. Thus, the enhancing effect of IL-12 may be based on an increased frequency of responding precursor cells. The results here presented demonstrate, to our knowledge for the first time, a definite role of IL-12 in the induction of a specific antibody response in human cells. Further, they stress the importance for such studies of appropriate in vitro systems. Finally, they show that the induction of primary immune responses in cultures of human peripheral blood lymphocytes mostly depends on the proper cytokine balance at different time points. PMID- 9368629 TI - Genetically modified bone marrow-derived dendritic cells expressing tumor associated viral or "self" antigens induce antitumor immunity in vivo. AB - The clinical application of synthetic tumor peptide-based vaccines is currently limited to patients with specified major histocompatibility complex (MHC) class I alleles. Such logistic limitations may be overcome using tumor gene-based approaches. Here we describe the effective generation of dendritic cells (DC) expressing tumor peptide-MHC complexes as a result of particle-mediated transfer of genes encoding tumor-associated antigens (TAA). Bone marrow-derived DC were transfected with plasmid DNA encoding the tumor-associated viral antigen E7 derived from human papilloma virus (HPV) 16. When applied as a vaccine, these genetically modified DC induced antigen-specific CD8+ cytotoxic T lymphocytes (CTL) in vivo and promoted the rejection of a subsequent, normally lethal challenge with an HPV 16-transformed tumor cell line. Of greatest interest, immunization of mice with syngeneic DC genetically modified to enhance their presentation of a constitutive "self" epitope derived from the tumor-suppressor gene product p53 caused a significant reduction in the in vivo growth of a chemically induced p53-positive sarcoma. These results suggest that cancer vaccines consisting of DC genetically modified to express TAA of viral or "self" origin effectively induce antitumor immunity in vivo. PMID- 9368630 TI - Host cell factor CD59 restricts complement lysis of Plasmodium falciparum infected erythrocytes. AB - Here we demonstrate that components of the entire complement cascade are fixed on the surface of erythrocytes infected with the human malarial parasite Plasmodium falciparum. Despite the activation of lytic complement factors, no complement mediated lysis of P. falciparum-infected erythrocytes occurred only in the absence of functional intrinsic CD59. These data suggest that the restriction of the complement attack of P. falciparum-infected erythrocytes is principally mediated by intrinsic host cell factors, in particular CD59. PMID- 9368631 TI - Impaired spontaneous endocytosis of HLA-G. AB - HLA-G is a class Ib (non-classical) major histocompatibility complex (MHC) protein expressed at the maternal-fetal interface that inhibits natural killer (NK) cell-mediated lysis in an allotype-independent manner. Here we report that the spontaneous endocytosis of HLA-G is severely reduced because of its short cytoplasmic tail. Class I (classical) MHC proteins on the surface of B cell transfectants detected by primary and secondary antibodies underwent endocytosis at a moderate rate, whereas HLA-G, chimeric proteins consisting of the extracellular domains of HLA-C with the C-terminal sequence of HLA-G, or glycophosphatidylinositol-tailed HLA-C proteins, were not efficiently internalized. In addition, a mutant of beta 2-microglobulin (Ser88Cys) that could be specifically labeled with Texas red (or other fluorescent probes) and exchanged into class I or class Ib MHC proteins was employed to study spontaneous internalization of MHC proteins by a non-perturbative method independent of an antibody ligand. These data are discussed in terms of both the role of HLA-G expressed on the fetal trophoblast and the function of the cytoplasmic tail in class I MHC proteins. PMID- 9368632 TI - Strong mucosal adjuvanticity of cholera toxin within lipid particles of a new multiple emulsion delivery system for oral immunization. AB - Cholera toxin (CT) is an effective mucosal adjuvant but causes significant intestinal secretion which limits its usefulness. In the present study we developed a new multiple emulsion (ME) delivery system into which antigen and CT could be incorporated and asked whether CT would retain its mucosal adjuvanticity when sequestered within emulsion particles. ME were selectively taken up into Peyer's patches, and those containing antigen plus CT generated intestinal secretory IgA and serum IgG antibody responses in mice comparable quantitatively and qualitatively to those occurring after oral immunization with soluble antigen plus CT. The ME particles containing CT did not cause intestinal secretion. The adjuvanticity of CT within ME was due to the CT present in the inner aqueous phase of the ME and was lost if CT binding was blocked by pre-incubation with GM1 ganglioside. Proteins incorporated in ME were protected from external acid, protease, and bile. We conclude that CT sequestered in ME, although unable to bind to the epithelium and thus stimulate intestinal secretion, still retains its mucosal adjuvanticity. Thus, the ability of CT to bind to enterocytes is not obligatory for its mucosal adjuvanticity. PMID- 9368633 TI - Antigen-specific and nonspecific deletion of immature cortical thymocytes caused by antigen injection. AB - Analysis of antigen-induced negative selection of thymocytes in T cell receptor (TCR)-transgenic mice is complicated by the presence of an antigen-responsive peripheral T cell compartment. Our experiments address the question of whether and how peripheral T cell activation can affect immature thymocytes. Following three daily injections of peptide antigen into mice expressing a peptide-specific transgenic TCR and deficient for TAP1, we and others have found profound deletion of the CD4+CD8+ (DP) thymocyte subset. However, our work shows that even though mature CD8+ T cells are inefficiently selected in TAP1-deficient mice, there was a striking degree of peripheral expansion and activation of CD8+ peripheral T cells. Furthermore, when cells from TCR-transgenic mice were adoptively transferred, we found that deletion of nontransgenic DP thymocytes occurred in Thy-1-congenic and even more efficiently in TAP1-deficient recipients after repeated peptide injection resulting in peripheral T cell activation. In the adoptive transfer experiments the degree of deletion of immature bystander thymocytes was decreased upon blocking of TNF. These data show that deletion of DP thymocytes can result from excessive peripheral T cell activation and identify TNF as an important effector molecule for this process. When steps are taken to avoid peripheral T cell activation, peptide antigen can induce TCR-mediated thymocyte deletion, presumably in the thymus cortex, since injection of TAP1 deficient TCR-transgenic mice resulted in deletion of immature DP thymocytes prior to detectable peripheral T cell expansion and activation. This effect was not blocked by inhibiting tumor necrosis factor activity. In addition, DP depletion was seen in the absence of peripheral T cell activation when antibody mediated depletion of CD8+ T cells was performed. Our work clearly shows that two mechanisms for deletion of DP thymocytes exist: deletion induced by antigen presentation in the thymus and deletion as a consequence of repeated stimulation of mature peripheral T cells. PMID- 9368634 TI - Granulocyte-macrophage colony-stimulating factor induces a unique set of STAT factors in murine dendritic cells. AB - Cytokine-mediated signaling pathways were studied in mouse dendritic cells (DC) by analysis of the activation pattern of STAT factors. Electrophoretic mobility shift assays were performed to detect STAT isoform-specific complexes. Granulocyte-macrophage colony-stimulating factor (GM-CSF) simultaneously induced complexes containing STAT1, STAT3, STAT5A, STAT5B and STAT6. In non-DC, a similar broad activation pattern of STAT factors by GM-CSF or other cytokines has not been observed so far. By comparison, in peritoneal macrophages, GM-CSF induced a complex with the properties of a truncated form of STAT5. Other cytokines tested on DC either failed to induce STAT factors [interleukin (IL)-1 beta, IL-2, IL 15], or activated the same STAT factors as observed in peritoneal macrophages (IL 4, IFN-gamma). Our results implicate a specific effect of GM-CSF on STAT signaling in DC which might account for the cell type-specific effect of this cytokine on development and function. PMID- 9368635 TI - Susceptibility to hard metal lung disease is strongly associated with the presence of glutamate 69 in HLA-DP beta chain. AB - Clinical, epidemiological and experimental data indicate that inhaled metal dust containing cobalt may produce an interstitial lung disease termed "hard metal disease" (HMD). Some aspects of this pathology such as the lack of correlation with dose exposure, the low frequency of the disease and the presence of T cells in the inflammation site, all suggest the existence of a genetic susceptibility, possibly to an immunological response to cobalt or to self proteins modified by cobalt. Here we report that HMD is strongly associated with residue Glu-69 of the HLA-DP beta chain. All patients, except for one with a rare genotype, possessed this marker as compared to 17 out of 35 exposed unaffected individuals (p = 0.0014). These data allow us to genetically distinguish a subgroup of cobalt exposed individuals at risk for HMD, independently from the more common allergic reaction. PMID- 9368636 TI - Major histocompatibility complex class I molecules interact with both subunits of the transporter associated with antigen processing, TAP1 and TAP2. AB - Prior to loading antigenic peptides, assembled major histocompatibility complex (MHC) class I molecules associate with the transporter associated with antigen processing (TAP) in a complex which also includes calreticulin and a recently described component, tapasin. The interaction of MHC class I molecules has been characterized as occurring exclusively with the TAP1 chain of the TAP heterodimer. In contrast, as described here, in the TAP-deficient human cell line T2, MHC class I molecules interact with a transfected rat TAP2 polypeptide in addition to rat TAP1. Furthermore, this interaction with TAP2 also involves calreticulin and tapasin. An association with both TAP polypeptides would presumably further enhance the efficiency of peptide loading of MHC class I molecules by allowing more than one MHC class I allele proximity to the site of peptide supply on each TAP complex. PMID- 9368637 TI - A new solid-phase radioimmunoassay to detect anti-GAD65 autoantibodies. AB - This paper describes a simple, rapid, routine method to detect anti-GAD65 autoantibodies by a solid-phase radioimmunoassay using human recombinant GAD65 coated microwells and 125I-protein A to reveal antibody binding. Both recombinant and radiolabelled proteins are commercially available. This new method was validated by investigating the presence of GAD65 autoantibodies in two different studies (A and B); the first including subjects originating from our own case histories (group A sera), the second made up of recoded subjects and standards sent to our lab by the Second International GAD Antibody Workshop organizers (group B sera). In study A we tested sera from 52 normal subjects, 25 newly diagnosed type 1 diabetics and 3 stiff man syndrome (SMS) subjects detecting GAD65 autoantibodies in 72% of IDDM and 100% of SMS patients. In study B we tested (in blind fashion) 89 recoded sample sera or standards that were part of the larger group used in the Second International GAD Antibody Workshop, finding GAD65 autoantibodies in 3.3% of healthy control subjects (1/30), 60% of IDDM patients (18/30), 100% of ICA + nondiabetic subjects (3/3) but in none of 4 nondiabetic patients with Graves disease. Comparing our solid-phase RIA results with those published for the same sera from the Second International GAD Antibody Workshop we obtained for our method a sensitivity of 85.7%, a specificity of 93.9% and a consistency of 100%. These result indicate that our assay, which is based on commercially available reagents, should be a useful tool for the detection of GAD65 autoantibodies in large scale studies. PMID- 9368638 TI - Analysis of single and double-stained alveolar macrophages by flow cytometry. AB - The quantification of cell surface antigens on human alveolar macrophages using flow cytometry is complicated by strong autofluorescence which varies with cell size and granularity. We report here a new method for overcoming the analytical problems caused by autofluorescence. After positioning the unstained cells along the 0, 0; 10(4), 10(4) diagonal on all three fluorescence dot-plots (FL1 vs. FL2; FL2 vs. FL3; FL1 vs. FL3) of a single-laser flow cytometer (excitation wavelength at 488 nm) and adjusting compensation so that the reference FL3 channel profile is not changed by PE-staining, the cell population on the FL3 histogram is arbitrarily classified into subpopulations having similar autofluorescence intensity. These are subsequently back-gated onto the FL1 vs. FL2 dot-plot and separately analyzed. The percentage of stained cells in the whole population is then calculated on the basis of absolute numbers or as the weighted mean of all the subpopulations. This approach permits the analysis not only of single-stained but also double-stained human alveolar macrophages. PMID- 9368639 TI - Quantitative assessment of myelin basic protein-reactive T cell entry to the central nervous system by using oligonucleotide probes complementary to VDJ junctional sequences of rat TCR beta-chain. AB - The VDJ junctional region represents the most diverse part of the antigenic TCR. We have previously reported that of 200 sequenced TCR beta-chains of rat MBP reactive T cells, rarely did two share sequence homology over the entire CDR3 region. In this study, we demonstrate that sequences of the TCR CDR3 region are excellent clonotypic markers for rat MBP-reactive T cell clones and oligonucleotide probes complementary to the CDR3 region of three T cell clones specifically recognized the TCR from which they were derived, but failed to recognize syngeneic T cells that express a similar TCR beta-chain or T cells that share both V beta and J beta usage. To explore this observation, we determined the ability of MBP-reactive T cell clones to enter the CNS. We were able to show that some MBP-reactive T cell clones have an augmented ability to enter the CNS and that fully-activated T cells have a higher penetrating activity than their less-activated T cell counterparts. PMID- 9368641 TI - Simple affinity purification of antibodies using in vivo biotinylation of a fusion protein. AB - We describe a method for affinity purification of antibodies using gene fusions to the antigen. Fusions are made to a protein domain which is recognized in vivo by biotin ligase and biotinylated at a unique position in the fusion protein. When expressed in E. coli, the fusion protein can be captured from a whole cell lysate using an avidin resin to generate an affinity column which is useful for antibody purification. The procedure is simple, rapid and does not require chemical biotinylation or prior purification of the target antigen. PMID- 9368640 TI - Human monocytoid cell lines as indicators of endotoxin: comparison with rabbit pyrogen and Limulus amoebocyte lysate assay. AB - The aim of this study was to develop an in vitro test system for pyrogenic substances. Three clones derived from human monocytoid cell lines, which were selected by their high sensitivity to lipopolysaccharide (LPS), were assessed for tumor necrosis factor (TNF) production. Their response to pyrogen-containing samples was compared with that in a Limulus amoebocyte lysate assay and the rabbit pyrogen test. We show here that the induction of TNF in these clones is a valid in vitro alternative to determine endotoxin in commercial preparations requiring pyrogenicity testing. Cell clones derived from Mono Mac 6 (MM6 2H8 and MM6 4B5) responded to sub-ng/ml concentrations of complete rough-strain and smooth-strain LPS, to ng/ml concentrations of diphosphoryl-lipid A, and to microgram/ml concentrations of monophosphoryl-lipid A and to detoxified LPS. Cells reacted to > or = 1 microgram/ml lipoteichoic acid by TNF production, and were relatively insensitive to toxic shock syndrome toxin-1 (TSST-1) and to muramyl dipeptide adjuvant peptide. The reaction pattern of a clone derived from THP-1 (THP-1 1G3) was in general, similar to that of the MM6 clones, except that THP-1 1G3 failed to react to diphosphoryl-lipid A. When tested on commercial samples destined for parenteral use, there was a close correlation between a sensitive Limulus amoebocyte lysate (LAL) test and the cell culture test on the one hand, and between the pyrogen test and the cell culture test on the other hand. The data suggest that this cell-based test is able to recognize pyrogens derived from gram-negative organisms in test samples with appropriate sensitivity and specificity. This test appears to be able to eliminate some of the false positive data obtained in the LAL test. PMID- 9368642 TI - A quick, easy and inexpensive method for the isolation of human peripheral blood monocytes. AB - A commercial monocyte isolation technique based on the OptiPrep density-gradient medium was up-scaled with respect to sample and reagent volumes. The results of 7 isolations are reported in which the average purity ranged from 87.9 to 96.4%. In all but the initial isolation, monocytes were defined as CD15+ dim CD4+ dim as assessed by flow cytometric analysis; in the first isolation, monocytes were defined by the traditional CD14+ CD4+ dim combination. The mean yield (the number of isolated monocytes relative to the number present in the buffy coat) of all isolations was 26.1%, with the individual yields ranging from 10.8 to 41.4%. The mean number of isolated monocytes per experiment was 3.6 x 10(6) monocytes for those isolations performed using 14 ml of buffy coat/OptiPrep mixture (n = 4). The isolated cells were viable (> 95%) and were not activated, according to HLA DR expression. This technique is a convenient, tast (less than 2 h), relatively simple, and inexpensive alternative to traditional monocyte isolation techniques. The up-scaled version of this method also results in significantly higher numbers of monocytes per isolation than some traditional techniques. Furthermore, this is the first literature report of the use of the OptiPrep density-gradient medium for the isolation of monocytes. PMID- 9368643 TI - Highly-sensitive and specific enzyme-linked immunosorbent assays for GAD65 autoantibodies using a thioredoxin-GAD65 fusion antigen. AB - Autoantibodies against glutamic acid decarboxylase (GAD65) are present in the sera of most patients with recently diagnosed insulin-dependent diabetes mellitus (IDDM). These antibodies appear years before the clinical symptoms, and they are considered to be early markers of the disease. To detect GAD65 autoantibodies (GADA), we developed new enzyme-linked immunosorbent assays (ELISA) with a fusion protein thioredoxin-GAD65 (Trx-GAD65) produced in E. coli as the antigen. These assays were compared with the reference radiobinding assay (RBA). Since most GADA are directed against native epitopes, and adsorption of GAD65 to plastic may cause disruption of its native conformation, the new assays rely on the following immobilization procedures: (a) capture ELISA (c-ELISA) with Trx-GAD65 (protocol A) or biotin-Trx-GAD (protocol B) indirectly immobilized by a non-adsorptive process; (b) ELISA with antigen-antibody preincubation in solution (p-ELISA) in which GADA were reacted first with Trx-GAD65 (protocol C) or biotin-Trx-GAD (protocol D) and the free antigen was determined by conventional ELISA. The results obtained with 42 newly diagnosed IDDM patients and 30 normal individuals were as follows: RBA had 79% sensitivity (percentage of IDDM patients detected) and 97% specificity (100% minus the percentage of false positives). c-ELISA showed low sensitivity (36 and 50%, respectively for protocols A and B), and high specificity (100 and 97%, respectively). p-ELISA were highly-sensitive (74 and 79%, respectively) and specific (97 and 93% for protocols C and D, respectively). Thus, protocols C and D had a performance similar to the reference method. The results reported here provide the basis for simple, highly-sensitive, specific, and widely-applicable tests for GADA that eliminate many of the drawbacks of the radioactive methods. PMID- 9368644 TI - Viral promoter expression in CEM-C7 and Jurkat human T-lymphoid cell lines. AB - The strength of various viral promoters was examined in human T lymphoblastoid cell lines. CMV, RSV and SV40 promoter based-luciferase constructs were transiently transfected into CEM-C7 and Jurkat cells in order to compare promoter strength in each cell type. It was found that the CMV promoter was 10-fold stronger than the RSV promoter in Jurkat cells, but equivalent to the RSV promoter in CEM-C7 cells. Both the CMV and RSV promoters were significantly stronger than the SV40 promoter in Jurkat and CEM-C7 cells. In summary, promoter strengths are cell line specific (Jurkat: CMV > RSV >> SV40; CEM-C7: RSV = CMV >> SV40) and care must be exercised in choosing promoters intended to provide overexpression of chimeric genes. PMID- 9368646 TI - Particle counting assay for anti-toxoplasma IgG antibodies. Comparison with four automated commercial enzyme-linked immunoassays. AB - An assay for anti-toxoplasma IgG antibodies based on agglutination of latex particles was set up and compared with commercial immunoassays. The reaction was measured by instrumental counting of particles remaining unagglutinated. The running time was 45 min. This test (PaC) was compared using 243 serum samples with four automated commercial immunoassays: the Enzymum test Toxo IgG (ES300, Boehringer), the Vidas Toxo IgG (Biomerieux), the IMX Toxo IgG (Abbott), the Magia Toxoplasma gondii IgG (Merck). The mean values (+/- SD) obtained by IMX (25 IU +/- 68) and ES300 (45 IU +/- 142) were significantly lower than the values obtained by Vidas (73 IU +/- 237, p < 10(-4) and p = 0.006, respectively), by Magia (80 IU +/- 300, p < 10(-4) and p = 0.0005) and by PaC (70 IU +/- 260, p < 10(-4) and p = 0.0126). The correlations between PaC and Toxo IgG Boehringer, Biomerieux, Abbott, Merck were r = 0.97, r = 0.98, r = 0.94, r = 0.98, respectively. The correlation coefficients between the enzyme-immunoassays ranged from 0.96 to 0.99. All positive samples by PaC were found to be positive by enzyme-immunoassays except for eight sera which were doubtful positives by the Enzymum test ToxoIgG from Boehringer. No negative sample by PaC was found positive by any of the enzyme-immunoassays. In PaC, when two latex preparations coated with different antigen were compared, the correlation was rather weak (r = 0.93) suggesting that the selection of the antigen can be critical. In conclusion, the four automated commercial immunoassays now available gave similar results. However, the discrepancies observed in this study underlined the importance of clinical and biological follow-up of the patients and the necessity to confirm the result. The introduction of a new technique such as PaC, which is now available for a large variety of assays in Clinical Chemistry and Microbiology, is justified by its intrinsic advantage of homogeneity. Therefore, automation is easy as well as the control of possible interference. PMID- 9368645 TI - Generation of monocyte-derived dendritic cells from precursors in rhesus macaque blood. AB - While the dendritic cells (DCs) of mouse and man have been extensively studied, until recently those of non-human primates remained poorly characterized. We present a method for generating large numbers of DCs from precursors in rhesus macaque blood, based on techniques developed for human blood. For 7 days, a T cell-depleted population of mononuclear cells was cultured in 1% human plasma with GM-CSF and IL-4, both to initiate DC differentiation and to inhibit macrophage development. On day 7, 50% of the culture medium was replaced with a monocyte-conditioned medium (MCM), which is required for the final maturation of the DCs into potent stimulators of the allogeneic MLR. Between 0.5 and 1.0 x 10(6) DCs can be generated from 20 ml of rhesus macaque blood. We compared these cytokine-generated DCs to the adherent macrophages present in the same cultures. Cytokine-generated DCs were considerably more potent at stimulating allogeneic T cells than adherent macrophages. Furthermore, the DCs had a distinct morphology and phenotype, with long processes, high levels of p55, and a characteristic perinuclear collection of intracellular CD68. In contrast, adherent macrophages expressed very low levels of p55, and high diffuse levels of CD68. Macaque DCs generated by this method may be useful in vaccine development and for studies of SIV pathogenesis. PMID- 9368647 TI - Generation of Cre recombinase-specific monoclonal antibodies, able to characterize the pattern of Cre expression in cre-transgenic mouse strains. AB - Transgene-encoded Cre recombinase can target alteration of loxP-tagged genes to specific cell types and developmental stages in mice, depending on the pattern of transgene expression. To facilitate determination of the latter, we have generated monoclonal anti-Cre antibodies which are specific for distinct epitopes on the recombinase and detect Cre both on immunoblots and intracellularly by immunofluorescence. We demonstrate the usefulness of these antibodies by an analysis of Cre expression in mice carrying a cre-transgene under B cell-specific control. PMID- 9368648 TI - Structure, recognition and adaptive binding in RNA aptamer complexes. AB - Novel features of RNA structure, recognition and discrimination have been recently elucidated through the solution structural characterization of RNA aptamers that bind cofactors, aminoglycoside antibiotics, amino acids and peptides with high affinity and specificity. This review presents the solution structures of RNA aptamer complexes with adenosine monophosphate, flavin mononucleotide, arginine/citrulline and tobramycin together with an example of hydrogen exchange measurements of the base-pair kinetics for the AMP-RNA aptamer complex. A comparative analysis of the structures of these RNA aptamer complexes yields the principles, patterns and diversity associated with RNA architecture, molecular recognition and adaptive binding associated with complex formation. PMID- 9368649 TI - Transcriptional analysis of the Caulobacter 4.5 S RNA ffs gene and the physiological basis of an ffs mutant with a Ts phenotype. AB - A temperature-sensitive (ts) mutation in the ffs gene, encoding 4.5 S RNA, gives rise to cell division and DNA replication defects in Caulobacter crescentus. The ffs gene is transcribed throughout the cell-cycle and is transcribed at similar rates in mutant (ffs36) and wild-type strains, but in the mutant the 4.5 S RNA is unstable leading to lower 4.5 S RNA levels. The ffs36 phenotype results from a single base change in one of the non-conserved stems of the mature RNA, and is completely rescued by a compensating mutation in the opposite strand, providing confirmation of the predicted secondary structure of the 4.5 S RNA. The Caulobacter ffs gene was shown to be functionally comparable to the Escherichia coli ffs gene by complementation. Comparison of the ffs36 strain to a ts secA strain of Caulobacter, also having cell-cycle and DNA replication phenotypes, showed that both exhibit a permanent induction of a heat shock response at the restrictive temperature. To explain the phenotype of both the secA and ffs36 strains, we propose that a cell-cycle checkpoint prevents further progression through the cell-cycle in response to increased intracellular levels of heat shock and misfolded proteins. PMID- 9368650 TI - The antiterminator RNA of phage HK022. AB - The put sites of phage HK022 increase the processivity of transcription and thereby promote the expression of viral genes that are located downstream of transcription terminators. RNA polymerase molecules that have traversed a put site are converted to a terminator-resistant form by the put transcript. We analyzed the structure and function of put transcripts by determining the effects of put mutations on terminator read-through, and by probing wild-type and mutant put RNAs with structure-specific nucleases. The results support the prediction that the secondary structure of the active transcript consists of two hairpin stems that are separated by a single unpaired base. The identity of bases in certain bulges and internal loops is important for activity, while that of most bases in the terminal loops is not. Many bases in the stems can be replaced with little or no effect on activity provided that base-pairing is maintained. PMID- 9368651 TI - Oligonucleotide inhibitors of human thrombin that bind distinct epitopes. AB - Thrombin, a multifunctional serine protease, recognizes multiple macromolecular substrates and plays a key role in both procoagulant and anticoagulant functions. The substrate specificity of thrombin involves two electropositive surfaces, the fibrinogen-recognition and heparin-binding exosites. The SELEX process is a powerful combinatorial methodology for identifying high-affinity oligonucleotide ligands to any desired target. The SELEX process has been used to isolate single stranded DNA ligands to human thrombin. Here, a 29-nucleotide single-stranded DNA ligand to human thrombin, designated 60-18[29], with a Kd of approximately 0.5 nM is described. DNA 60-18[29] inhibits thrombin-catalyzed fibrin clot formation in vitro. Previously described DNA ligands bind the fibrinogen-recognition exosite, while competition and photocrosslinking experiments indicate that the DNA ligand 60-18[29] binds the heparin-binding exosite. DNA 60-18[29] is a quadruplex/duplex with a 15-nucleotide "core" sequence that has striking similarity to previously described DNA ligands to thrombin, but binds with 20 to 50-fold higher affinity. The 15-nucleotide core sequence has eight highly conserved guanine residues and forms a G-quadruplex structure. A single nucleotide within the G-quadruplex structure can direct the DNA to a distinct epitope. Additional sequence information in the duplex regions of ligand 60-18[29] contribute to greater stability and affinity of binding to thrombin. A low-resolution model for the interaction of DNA 60-18[29] to human thrombin has been proposed. PMID- 9368652 TI - The RecBCD enzyme initiation complex for DNA unwinding: enzyme positioning and DNA opening. AB - The Escherichia coli RecBCD enzyme unwinds DNA from a free double-stranded DNA end to produce single-stranded DNA intermediates of homologous recombination. In the absence of ATP RecBCD binds to a free DNA end to form an initiation complex for DNA unwinding. We studied the structure of these complexes formed with blunt ended, 5'-extended, and 3'-extended DNA. Reactivity to the single-stranded DNA specific reagents KMnO4 and dimethyl sulfate indicated that RecBCD opened, in a Mg(2+)-dependent manner, the terminal five or six base-pairs in each substrate. Thymine residues located four to six nucleotides from the 5' end were only partially reactive to KMnO4, suggesting that part of the 5'-terminated strand was partially shielded by the enzyme. DNase I footprinting indicated that the enzyme positions itself relative to the end of the longer of the two strands, although an exception was noted. These results imply flexibility in the ability of RecBCD to open the DNA and position itself for unwinding on DNA with different types of ends. They also imply conformational differences of RecBCD enzyme bound to different types of ends; these conformational differences may be related to those occurring during the unwinding cycle. PMID- 9368653 TI - Nuclear protein import is decreased by engineered mutants of nuclear transport factor 2 (NTF2) that do not bind GDP-Ran. AB - Nuclear transport factor 2 (NTF2) is associated with the translocation stage of nuclear protein import and binds both to nuclear pore proteins (nucleoporins) containing phenylalanine-rich repeats and to the Ras family GTPase Ran. In this study we probed the role of the NTF2-Ran interaction in nuclear protein import using site-directed mutants of NTF2 that interfere with its interaction with GDP Ran. The design of these mutants was based on the X-ray crystal structure of NTF2 and was concentrated on conserved residues in and around the molecule's hydrophobic cavity. The mutant NTF2 cDNAs were expressed in Escherichia coli. Purified mutant proteins retained the interaction with FxFG-repeat nucleoporins, but several mutants in the negatively charged residues that surround the NTF2 cavity or in residues in the cavity itself were unable to bind GDP-Ran in vitro. The crystal structure of the E42K mutant protein showed significant structural changes only in this side-chain, indicating that it participated directly in the interaction with GDP-Ran. In permeabilised cell nuclear protein import assays, only wild-type NTF2 and mutants that bound GDP-Ran were functional. Furthermore, when the NTF2 E42K and D92N/D94N NTF2 mutants that failed to bind GDP-Ran in vitro were substituted for the chromosomal yeast NTF2, the yeast cells became non viable, whereas yeast substituted with wild-type human NTF2 remained viable. We conclude that interaction between NTF2 and GDP-Ran is important for efficient nuclear protein import. PMID- 9368654 TI - Helix-loop-helix motif in GnRH associated peptide is critical for negative regulation of prolactin secretion. AB - The GnRH associated prolactin inhibiting factor (GAP) reveals the signature sequence associated with the helix-loop-helix structural motif. A number of different peptide fragments of GAP were designed, synthesized and analysed by circular dichroism and by an in vivo assay for prolactin secretion inhibiting activity. Peptides corresponding to the two individual alpha-helices and a 44 residue peptide comprising the entire helix-loop-helix motif show significant helical propensity in circular dichroism spectra. However, a peptide corresponding to the loop sequence shows no helical propensity. Albeit, the peptide corresponding to helix-loop-helix motif was found to inhibit prolactin secretion and augment circulating levels of gonadotropins in the in vivo assay; other shorter peptides did not show such activity. The activity profile of the 44 residue peptide was biphasic and very similar to that of the recombinant GAP. Thus, the prolactin inhibiting activity of this factor is defined by its helix loop-helix motif as in the case of the transcription factors of developmental genes. The structural features of a homology-based model of GAP in complex with E47, a ubiquitous HLH-type developmental gene regulator, are consistent with the structural requirements of the negative regulation of transcription by helix-loop helix proteins. PMID- 9368655 TI - Photosystem I of Synechococcus elongatus at 4 A resolution: comprehensive structure analysis. AB - An improved structural model of the photosystem I complex from the thermophilic cyanobacterium Synechococcus elongatus is described at 4 A resolution. This represents the most complete model of a photosystem presently available, uniting both a photosynthetic reaction centre domain and a core antenna system. Most constituent elements of the electron transfer system have been located and their relative centre-to-centre distances determined at an accuracy of approximately 1 A. These include three pseudosymmetric pairs of Chla and three iron-sulphur centres, FX, FA and FB. The first pair, a Chla dimer, has been assigned to the primary electron donor P700. One or both Chla of the second pair, eC2 and eC'2, presumably functionally link P700 to the corresponding Chla of the third pair, eC3 and eC'3, which is assumed to constitute the spectroscopically-identified primary electron acceptor(s), A0, of PSI. A likely location of the subsequent phylloquinone electron acceptor, QK, in relation to the properties of the spectroscopically identified electron acceptor A1 is discussed. The positions of a total of 89 Chla, 83 of which constitute the core antenna system, are presented. The maximal centre-to-centre distance between antenna Chla is < or = 16 A; 81 Chla are grouped into four clusters comprising 21, 23, 17 and 20 Chla, respectively. Two "connecting" Chla are positioned to structurally (and possibly functionally) link the Chla of the core antenna to those of the electron transfer system. Thus the second and third Chla pairs of the electron transfer system may have a dual function both in energy transfer and electron transport. A total of 34 transmembrane and nine surface alpha-helices have been identified and assigned to the 11 subunits of the PSI complex. The connectivity of the nine C-terminal (seven transmembrane, two "surface") alpha-helices of each of the large core subunits PsaA and PsaB is described. The assignment of the amino acid sequence to the transmembrane alpha-helices is proposed and likely residues involved in co ordinating the Chla of the electron transfer system discussed. PMID- 9368656 TI - The structural stability of the co-chaperonin GroES. AB - The structural stability of the co-chaperonin GroES has been studied by high sensitivity differential scanning calorimetry and circular dichroism under different solvent conditions. The thermal folding/unfolding of GroES is a spontaneous reversible process involving a highly cooperative transition between folded heptamers and unfolded monomers. During the denaturation process folded monomers are energetically unfavourable and consequently never become populated to an appreciable degree. Analysis of the high resolution structure indicates that isolated folded monomers of GroES bury a significantly smaller fraction of their total surface than typical globular proteins of similar molecular mass. For this reason the intramolecular interactions within each GroES monomer appear not to be sufficient for thermodynamic stabilization. The stabilization of the heptameric structure is due primarily to intersubunit interactions rather than intrasubunit interactions. These interactions favor oligomerization both enthalpically and entropically. Despite the high density of charged residues, the stability of GroES shows no measurable dependence on salt concentration at pH 7. On the other hand, millimolar concentrations of magnesium stabilize GroES, presumably by specific binding. The stabilization elicited by Mg2+ is consistent with a dissociation constant of the order of 0.5 mM and approximately three binding sites per heptamer. These results emphasize the role of quaternary structure in the stabilization of small oligomeric proteins. PMID- 9368657 TI - Helix packing in membrane proteins. AB - A survey of 45 transmembrane (TM) helices and 88 helix packing interactions in three independent transmembrane protein structures reveals the following features. (1) Helix lengths range from 14 to 36 residues with an average length of 26.4 residues. There is a preference for lengths greater than 20 residues. (2) The helices are tilted with respect to the bilayer normal by an average of 21 degrees, but there is a decided preference for smaller tilt angles. (3) The distribution of helix packing angles is very different than for soluble proteins. The most common packing angles for TM helices are centered around +20 degrees while for soluble proteins packing angles of around -35 degrees are the most prevalent. (4) The average distance of closest approach is 9.6 A, which is the same as soluble proteins. (5) There is no preference for the positioning of the point of closest approach along the length of the helices. (6) It is almost a rule that TM helices pack against neighbors in the sequence. Of the 37 helices that have a sequence neighbor, 36 of them are in significant contact with a neighbor. (7) An antiparallel orientation is more prevalent than a parallel orientation and antiparallel interactions are more intimate on average. The general features of helix bundle membrane protein architecture described in this survey should prove useful in the modeling of helix bundle transmembrane proteins. PMID- 9368658 TI - Contributions to protein entropy and heat capacity from bond vector motions measured by NMR spin relaxation. AB - The backbone dynamics of both folded and unfolded states of staphylococcal nuclease (SNase) and the N-terminal SH3 domain from drk (drkN SH3) are studied at two different temperatures. A simple method for obtaining order parameters, describing the amplitudes of motion of bond vectors, from NMR relaxation measurements of both folded and unfolded proteins is presented and the data obtained for 15N-NH bond vectors in both the SNase and drkN SH3 systems analyzed with this approach. Using a recently developed theory relating the amplitude of bond vector motions to conformational entropy, the entropy change between the folded and unfolded forms of SNase is calculated on a per residue basis. It is noteworthy that the region of the molecule with the smallest entropy change includes those residues showing native-like structure in the unfolded form of the molecule, as established by NOE-based experiments. Order parameters of backbone 15N-NH bond vectors show significantly larger changes with temperature in the unfolded states of both proteins relative to the corresponding folded forms. The differential temperature dependence is interpreted in terms of differences in the heat capacities of folded and unfolded polypeptide chains. The contribution to the heat capacity of the unfolded chain from rapid 15N-NH bond vector motions is calculated and compared with estimates of the heat capacity of the backbone unit, -CHCONH-, obtained from calorimetric data. Methyl dynamics measured at 14 and 30 degrees C establish that the amplitudes of side-chain motions in the folded SH3 domain are more sensitive to changes in temperature than the backbone dynamics, suggesting that over this temperature range side-chain ps to ns time-scale motions contribute more to the heat capacity than backbone motions for this protein. PMID- 9368659 TI - Recommendations for the biopsy procedure and assessment of skeletal muscle biopsies. AB - Muscle biopsy has a valuable diagnostic role in many neuromuscular diseases, but it is an invasive investigation that should not be undertaken lightly. Furthermore, the biopsy procedure and subsequent laboratory processing of the specimen may significantly influence the results. The following guide is designed to optimise the diagnostic information that can be obtained from muscle biopsy. It covers the whole procedure, from selection of the biopsy site and technique of biopsy, progressing through freezing of the specimen for histochemistry, and the role of immunocytochemistry and electron microscopy. Finally, the contents of a model biopsy report are considered. PMID- 9368660 TI - Helicobacter pylori antigen in the glomeruli of patients with membranous nephropathy. AB - Renal biopsy specimens from patients with membranous nephropathy (MN) were studied using immunohistochemical labelling to clarify the aetiological significance of Helicobacter pylori antigen in this disease. Sixteen specimens were examined, from 7 male and 9 female MN patients. Renal specimens from patients with diabetic nephropathy and IgA nephropathy, and from autopsied patients without renal diseases were obtained as controls. Immunohistochemical labelling was performed using one polyclonal antibody and three monoclonal antibodies against H. pylori. Specimens from 11 of the MN patients revealed granular deposits along the glomerular capillary walls, which reacted positively with polyclonal antibody after trypsin pretreatment. None of the control specimens revealed positive labelling. The MN specimens showed no positive reaction with the primary antibody, which had been treated for immunoabsorption testing using sonicated H. pylori. We also determined H. pylori status in these MN patients histologically and/or serologically. Of the 11 patients whose glomeruli were positive for anti-H. pylori antibody, 7 were suitable for analysis, and all were regarded as positive for H. pylori infection. These results suggest that the presence of a specific antigen in the glomeruli of patients with MN and H. pylori infection may be involved in the pathogenesis of MN. PMID- 9368661 TI - Frequency of apoptosis relates inversely to invasiveness and metastatic activity in human colorectal cancer. AB - The frequency of apoptosis was determined in 102 cases of human colorectal cancer. The results were correlated with the frequency of cell proliferation and with clinicopathological characteristics such as degree of differentiation, invasiveness and metastasis. As a marker of apoptosis, intranuclear DNA strand breaks were localized with in situ nick translation (ISNT). As a marker of proliferation, proliferating cell nuclear antigen (PCNA) was localized immunohistochemically. The numbers of nuclei positive with ISNT and for PCNA per 1,000 nuclei on tissue sections were obtained. The labelling indices were compared with clinicopathological characteristics for each tumour. The ISNT labelling index of well differentiated colon carcinomas was higher than that of poorly differentiated carcinomas. Among similarly differentiated cancers, ISNT L.I. of colon carcinomas classified as Dukes A was higher than Dukes B/C, and L.I. of carcinomas which did not metastasize to lymph node or liver was higher than that of carcinomas which metastasized. The PCNA labelling index did not correlate with any of the clinicopathological characteristics or with the ISNT labelling index. The data suggest that apoptosis indices severe as a marker of tumour progression. PMID- 9368662 TI - Characteristics of rhabdomyosarcoma cell lines derived from uterine carcinosarcomas. AB - Rhabdomyosarcoma (RMS) is occasionally found in the female genital tract, and mostly appears as one of the heterologous mesenchymal components in uterine carcinosarcoma designated as malignant mixed mullerian tumour (MMMT). We examined the biological properties of a pure rhabdomyosarcoma (RMS) cell line designated FU-MMT-3, which was newly established from a surgical specimen taken from a patient with uterine MMMT. We also evaluated c-myc and MYCN gene amplification in three RMS cell lines (including FU-MMT-3) derived from three MMMTs by Southern blot analysis. FU-MMT-3 cells were propagated continuously for 57 serial passages over a 2-year period in vitro. FU-MMT-3 was able to produce tumours demonstrating pure RMS in athymic nude mice. Cytogenetically, FU-MMT-3 showed a triploidy pattern, with complex karyotypic abnormalities including trisomy of chromosome 8. All three RMS cell lines, including FU-MMT-3, showed amplification of the c-myc gene (approximately fourfold to eightfold), while no cell lines demonstrated MYCN gene amplification. FU-MMT-3 is considered to provide a useful system for the study of the biological behaviour of RMS in MMMTs. Extra copies of chromosome 8 and c-myc gene amplification may be associated with the rhabdomyoblastic differentiation in MMMT. PMID- 9368663 TI - Establishment and characterization of spontaneous mesothelioma cell lines derived from F344 rats. AB - Three mesothelioma cell lines (MeET-4, MeET-5, and MeET-6) established from ascitic fluid of F344 rats with spontaneous abdominal mesothelioma have been maintained through at least 60 passages on the DMEM with 10% FBS. Two of original tumours consisted of epithelioid cells growing in a papillary pattern, while one (original tumour of MeET-5) had sarcomatous areas composed of spindle-shaped tumour cells. The cell line originating from MeET-5 showed a constantly beiphasic growth pattern during the repetitive subcloning, while the other two lines retained a monophasic growth pattern. Although the growth pattern was different, the tumour cells in all three lines were positive for vimentin and keratin and ultrastructurally showed an abundant distribution of glycogen granules in the cytoplasm and numerous long microvilli on all surface. The modal chromosome number of cell lines varied from 41 to 71, and abnormal chromosomes were frequently seen. All cell lines established formed colonies on semi-solid medium and could be successfully transplanted, growing tumour masses in syngeneic rats and thus indicating their malignant nature. Cell lines grew even on a medium with a low concentration of FBS. The evidence suggests that they may produce growth factors that enable them to survive unfavourable medium conditions. PMID- 9368665 TI - Broncho-bronchiolitis obliterans as a complication of bone marrow transplantation: a clinicopathological study of eight autopsy cases. Nagoya BMT Group. AB - We identified eight patients with bronchiolitis obliterans (BO) in the autopsies of 81 bone marrow transplant (BMT) recipients. Rapidly progressive dyspnoea and cough were the main presenting symptoms in all eight patients, associated with overinflation and/or infiltrative opacity seen on chest X-ray and obstructive disorder revealed by pulmonary function tests. Early lesions were characterized by epithelial loss and an inflammatory infiltrate containing foamy histiocytes with mild luminal narrowing. Partial or total occlusion of the bronchiolar lumina by fibrous connective tissue was the feature of late lesions. Both changes were coexistent in all cases. In one case, small bronchi with cartilage were also affected by the obstructive process, showing bronchitis obliterans. All eight patients showed non-obstructive broncho-bronchiolitis characterized by denuding of respiratory epithelium, mural oedema and an inflammatory infiltrate in addition to BO, and these changes were also seen in 18 patients without BO. The submucosal glands of large bronchi and the trachea showed mucous retention and a mild inflammatory infiltrate in four of the eight patients. Coexistent infectious processes were seen in all cases, cytomegalovirus and Aspergillus being the most frequent organisms. BO probably develops as an immunopathological event related to graft-versus-host disease (GVHD) during the impaired immune status phase of the post-BMT period, possibly initiated by infection. Bronchial gland involvement in chronic GVHD is one of the factors responsible for this abnormal immune status. PMID- 9368664 TI - Structural analysis of arteriolar and myocardial remodelling in the subendocardial region of patients with hypertensive heart disease and hypertrophic cardiomyopathy. AB - Left ventricular hypertrophy is a risk factor for cardiovascular morbidity and mortality. In arterial hypertension and in hypertrophic cardiomyopathy it may be accompanied by clinical signs of myocardial ischaemia resulting from microcirculatory dysfunction in the absence of coronary macroangiopathy. Structural changes of the vascular and interstitial compartment of the heart are involved in the pathogenesis of impaired microcirculation. We investigated patients with hypertensive heart disease (HHD; n = 12) and hypertrophic cardiomyopathy (HCM; n = 19) without coronary macroangiopathy but with signs of myocardial ischaemia. Right septal endomyocardial biopsies were evaluated to quantify the structure of intramyocardial arterioles, collagen content and myocytic diameter by morphometric rules. Nine normotensive subjects served as controls. The groups differed significantly (P < 0.05) in myocytic diameter and total collagen content. The myocytic diameter correlated with the thickness of the interventricular septum. Arterioles in HHD showed a significant increase in cross-sectional medial area and in HHD patients the periarteriolar collagen area increased both in absolute terms and when standardized to medial area. Arteriolar density was significantly reduced in HCM. In a multivariate discriminant analysis the positive predictive value for differentiation of the groups by non-myocytic variables was 72.5% (P = 0.013). HHD and HCM differ in the structural alterations in the arteriolar bed. Medial hypertrophy and periarteriolar fibrosis prevail in HHD, and reduced arteriolar density is found in HCM. Different microvascular remodelling at the level of arterioles indicates distinct pathophysiologic processes that may contribute to the clinically observed disturbance of coronary microperfusion in these two diseases. PMID- 9368666 TI - Dynamics of the ultrastructural changes in blood and lymphatic capillaries of bronchi in inflammation and following endobronchial laser therapy. AB - An ultrastructural and autoradiographic analysis of changes in 188 biopsy specimens of bronchial mucosa of the large bronchi from 76 patients with chronic inflammatory lung diseases was carried out. Fibrosis results in an apparent reduction of metabolic activity in endothelial cells, affecting the proliferation of basal cells with changes in cell differentiation. Endobronchial laser therapy with an helium-neon laser induces proliferative and metabolic processes in the lamina propria of the bronchial mucosa with hyperaemia, intensive diapedesis of leucocytes and formation of leucocytic infiltrations and granulation tissue. The proliferative and metabolic activity of endothelial and stromal cells increases, and delicate fibrous connective tissue is formed. PMID- 9368667 TI - Papillary carcinoma of the thyroid with exuberant nodular fasciitis-like stroma. AB - We describe a rare case of papillary carcinoma with extensive proliferation of stromal cells. The stromal cells were immunocytochemically positive for vimentin, alpha-smooth muscle actin and desmin, but negative for cytokeratin, epithelial membrane antigen, S-100, thyroglobulin and CD34. These results and the ultrastructure of the stromal cells, which exhibited the characteristics of both fibroblasts and smooth muscle cells, indicated an origin from myofibroblasts. We conclude that myofibroblastic proliferation may contribute to the stromal response in the slow growth of the papillary carcinoma. PMID- 9368668 TI - Molecular mechanisms of thrombin function. AB - The discovery of thrombin as a Na(+)-dependent allosteric enzyme has revealed a novel strategy for regulating protease activity and specificity. The alllosteric nature of this enzyme influences all its physiologically important interactions and rationalizes a large body of structural and functional information. For the first time, a coherent mechanistic framework is available for understanding how thrombin interacts with fibrinogen, thrombomodulin and protein C, and how Na+ binding influences the specificity sites of the enzyme. This information can be used for engineering thrombin mutants with selective specificity towards protein C and for the rational design of potent active site inhibitors. Thrombin also serves as a paradigm for allosteric proteases. Elucidation of the molecular basis of the Na(+)-dependent allosteric regulation of catalytic activity, based on the residue present at position 225, provides unprecedented insights into the function and evolution of serine proteases. This mechanism represents one of the simplest and most important structure-function correlations ever reported for enzymes in general. All vitamin K-dependent proteases and some complement factors are subject to the Na(+)-dependent regulation discovered for thrombin. Na+ is therefore a key factor in the activation of zymogens in the coagulation and complement systems. PMID- 9368669 TI - Strategies for development of novel antithrombotics: modulating thrombin's procoagulant and anticoagulant properties. AB - Thrombin is a serine proteinase that can interact with a large number of diverse macromolecular substrates, which results in either a procoagulant or anticoagulant effect. These divergent properties are physiologically regulated by the endogenous protein thrombomodulin. This review summarizes recent work on a variety of methods used to exploit the allosteric nature of the enzyme. The procoagulant and anticoagulant functions of thrombin can be modulated by sodium binding, site-directed mutagenesis, and a small synthetic molecule. Modulation of thrombin's intrinsic properties represents a novel approach to the development of unique antithrombotic agents. PMID- 9368670 TI - Calphostin C synergistically induces apoptosis with VP-16 in lymphoma cells which express abundant phosphorylated Bcl-2 protein. AB - A newly established human lymphoma cell line (OZ) has the t(14;18)(q32;q21) translocation and expresses large amounts of Bcl-2 compared to CCRF-CEM cells. VP 16 (40 micrograms/mL), a promising agent against lymphoma, caused DNA fragmentation (26.9% of total DNA) typical for apoptosis at 6 h in CCRF-CEM cells, but no significant changes in OZ cells until 24 h after the addition of VP 16. However, coincubation with calphostin C (0.2 microgram/mL), a protein kinase C (PKC) inhibitor, induced DNA fragmentation in VP-16-treated OZ cells (13.5% of total DNA) at 6 h after the treatment. Simultaneous immunoblot analysis revealed that this induction of apoptosis coincided with the downregulation of serine phosphorylated Bcl-2 (13% of control cells). By contrast, apoptosis induced by VP 16 in CCRF-CEM cells was attenuated by the addition of 0.5 microM phorbol 12 myristate 13-acetate, a potent PKC stimulator. These observations suggest that Bcl-2 function is partly regulated by phosphorylation/ dephosphorylation mechanisms of the PKC system, and that phosphorylated Bcl-2 in lymphoma cells may play a role in the prevention of apoptosis. PMID- 9368672 TI - Augmentation of natural antiganglioside IgM antibodies in lower motor neuron disease (LMND) and role of CD5+ B cells. AB - IgM antibodies directed against neuronal gangliosides GM1, GM2, GD1a, GD1b and GT1b occur in normal individuals and their level significantly decreases with age. Patients with lower motor neuron disease (LMND) produce high levels of these autoantibodies. AntiGM1 IgM is selectively augmented. In these patients, the CD5+ (B1) and CD5- (B2) subsets of B cells are not distinct entities but range from those without detectable CD5 marker to those with high CD5+ expression. B1 B cells were sorted to homogeneity, but B2 B cell cannot be isolated to homogeneity because of the presence of B1 cells with low CD5 expression. In short term cultures both the subsets produced IgM antibodies, but the antibodies reacted better with desialylated GM1 than with GM1. Cycloheximide (Cx) (0.35 mM) largely blocked IgM synthesis of the B1 B cells but inhibition of the B2 B cells was incomplete, possibly due to shedding of cytophilic antibodies as well as to the presence of B1 phenotype with loss of CD5 expression. CD5+ B cells may be involved in the production of antiglycolipid IgM. PMID- 9368671 TI - Candida albicans morphogenesis is influenced by estrogen. AB - Conversion of Candida albicans from yeast to mycelial growth is believed to be associated with the organism's virulence. We investigated the role of mammalian hormones in initiating this transformation. Three clinical isolates of Candida albicans were tested for their ability to produce germ tubes under various conditions. Controlled hormonal conditions were provided by stripping rabbit serum with activated charcoal. Steroid compounds under investigation were added back to the stripped serum and yeast were inoculated into the test materials. Microscopic counts of germinated versus ungerminated cells were used as an indicator of morphogenic transformation. The percent of yeast cells germinating was profoundly reduced in stripped compared to unstripped serum. The addition of 1 microM estradiol, cholesterol or testosterone only slightly increased levels of germination above that seen in controls. Estradiol at concentrations 100 times less, however, proved a strong inducer of germination. Cholesterol did not synergize germination when combined with estradiol and the alpha isomer of estradiol had almost no activity as an inducer of morphogenic change in Candida albicans. We conclude that beta estradiol was a morphogenic inducer in three clinical isolates of Candida albicans but only at concentrations typical in vivo. PMID- 9368673 TI - Purification and characterization of multiple glutathione transferase isoenzymes from grey mullet liver. AB - Fourteen isoforms of glutathione S-transferase (GST) have been separated and purified from mullet (Mugil cephalus) liver by scaling up an automatic analytical method based on anionic exchange chromatography. The activity of each isoenzyme with several substrates was determined. Dimeric combinations of six subunits make up this heterogeneous isoenzyme population. Five of these were resolved by reverse phase chromatography; four of them, named a, b, c and d, were present in more than one isoform, had the same apparent molecular mass (25.2 kDa) by SDS PAGE, and were immunochemically related to plaice GST-A and possibly to rat GST-5 but not to plaice GST-B or any other rat GST subunit; they would belong to the theta class. Subunit e was only present in isoenzyme I which was basic, had an apparent molecular mass of 23.4 kDa and would belong to the alpha class, since it was recognized by antibodies towards plaice GST-B and rat GST-1 and GST-8 and less intensely by anti-(rat)GST-2. Another subunit, named f, with 25.2 kDa apparent molecular mass that could not be distinguished by reverse phase chromatography, was detected immunochemically by positive reaction with antibodies to rat GST-1 and GST-2 in addition to reaction with anti-(plaice)GST A. As suggested by these results we discuss the existence of genetic polymorphism, the differential expression and the evolutionary relationships of mullet GSTs. PMID- 9368674 TI - Stimulation by enkephalins of D-glucose absorption in rabbit ileum. AB - In intact tissue, DAGO ([D-Ala2, MePhe4, Gly-ol5]enkephalin; 10(-5) M; mu-ligand; addition on the serosal side) stimulated D-glucose absorption and D-glucose dependent variations in short-circuit current (delta Isc,glu); naloxone (10(-6) M) antagonized these effects. DADLE ([D-Ala2, D-Leu5]enkephalin, mainly a delta ligand; 10(-5) M) and (pCl-Phe4)-DPDPE ([D-pen2, p-chloro-Phe4, D Pen5]enkephalin, a more selective delta-ligand; 10(-5) M) did not significantly stimulate delta Isc,glu (addition on the serosal side). In the absence of the muscularis and myenteric plexus or using intact tissue treated with tetrodotoxin (TTX; 3 x 10(-7) M), DAGO was unable to increase delta Isc,glu. Addition of DAGO to the mucosal side did not induce any variations in delta Isc,glu. In conclusion, DAGO is able to increase D-glucose absorption by interacting with mu receptors located in the myenteric plexus. PMID- 9368675 TI - Can animal researchers and their supporters engage in useful dialogue with animal "protectionists"? PMID- 9368676 TI - Acute, nongenomic actions of the neuroactive gonadal steroid, 3 alpha-hydroxy-4 pregnen-20-one (3 alpha HP), on FSH release in perifused rat anterior pituitary cells. AB - We have previously shown that the gonadal and neurosteroid, 3 alpha-hydroxy-4 pregnen-20-one (3 alpha HP), can selectively suppress gonadotrophin-releasing hormone (GnRH) induced follicle-stimulating hormone (FSH) release from static cultures of anterior pituitary cells during a 4-h incubation period. The actions appeared to be at the level of the gonadotroph membrane and the cell signaling pathway involving Ca2+ and protein kinase C (PKC). In order to investigate further if the effects of 3 alpha HP on FSH release are generated by nongenomic mechanisms, we monitored the short-term effects of 3 alpha HP using dispersed anterior pituitary cells in a low dead-volume perifusion system with short (< or = 5 min) exposures to the steroid. Pulses of GnRH (10(-8) or 10(-7) M) lasting 2 5 min resulted in marked peaks of FSH release, and the variation in FSH amounts released from the cells in a particular column were minimal if the interval between successive GnRH pulses was at least 3-4 h. A 5-min pulse of 3 alpha HP (10(-9) M) administered simultaneously with the GnRH pulse suppressed GnRH induced FSH release. On the other hand, similar treatment with the stereoisomer 3 beta-hydroxy-4-pregnen-20-one (3 beta HP), had no effect, but progesterone and estradiol pulses augmented the GnRH-induced FSH release. Pretreatment of cells with a 5-min pulse of 3 alpha HP, at 120, 60, or 30 min prior to a GnRH pulse suppressed the GnRH-induced FSH release. The suppression of GnRH-induced FSH release by 3 alpha HP was only partial if the start of the 3 alpha HP pulse occurred 0.5 or 1.0 min after the start of the GnRH pulse, and no suppression occurred if the start of the 3 alpha HP pulse was delayed by 2-5 min. The FSH release elicited by 5-min pulses of the Ca2+ ionophore A23187, the Ca2+ agonist BAY K8644, the PKC activator phorbol 12-myristate 13-acetate (PMA), or phospholipase C (PLC) was suppressed by simultaneous pulses of 3 alpha HP. The suppression of FSH release by 3 alpha HP appeared to be stereospecific, since no suppression was observed with 5 alpha-pregnane-3,20-dione (5 alpha P) or 3 alpha hydroxy-5 alpha-pregnan-20-one (5 alpha P3 alpha). In separate experiments, cells were treated with pulses of BSA conjugates of 3 alpha HP, 3 beta HP, or progesterone; the 3 alpha HP-BSA, but not the 3 beta HP-BSA or the progesterone BSA, suppressed the GnRH-induced release of FSH. The results of this study provide the first evidence that 3 alpha HP exerts immediate (nongenomic) and direct effects on GnRH-induced FSH release by interacting at the level of the pituitary gonadotroph membrane and the phosphoinositol cell signaling cascade involving Ca2+. PMID- 9368677 TI - Thyroid autoantibodies and thyroid dysfunction during treatment with interferon alpha for chronic hepatitis C. AB - Interferon-alpha (2a or 2b) is increasingly used for treatment of chronic hepatitis C virus (HCV) infection. Recent reports suggested a correlation between increases in thyroid autoantibodies and the development of thyroid dysfunction during interferon-alpha therapy. In this study, we analyzed thyroid hormones and antithyroid antibodies at monthly intervals in 53 patients who received interferon alpha for chronic active hepatitis C infection. Of five patients with initially elevated levels of antithyroid peroxydase antibodies (anti-TPO), the antibodies increased further in two of them. Ten patients, who started interferon therapy with normal antibody levels, developed elevated anti-TPO antibodies for limited times during treatment. Levels of anti-TPO antibodies showed a marked fluctuation, and only three patients had increased anti-TPO antibodies persisting for longer than 3 mo. Antithyroglobulin antibodies appeared in four patients, all of whom were also positive for anti-TPO antibodies. No changes in TRAB levels were observed. All of these patients with elevated antithyroid antibodies remained in an euthyroid state. One patient with normal antithyroid antibodies developed thyroiditis with severe thyrotoxicosis after 9 wk of interferon therapy. These findings suggest that the induction of antithyroid antibodies during treatment with interferon-alpha does not indicate clinical relevant thyroid dysfunction. Routine measurement of antithyroid antibodies during interferon-alpha therapy does not seem to be mandatory. PMID- 9368678 TI - Insulin-like growth factor binding protein-3 and -5 are regulated by transforming growth factor-beta and retinoic acid in the human prostate adenocarcinoma cell line PC-3. AB - The family of insulin-like growth factor binding proteins (IGFBPs) can affect cell proliferation by modulating the availability and bioactivity of insulin-like growth factors (IGFs), or by mechanisms independent of IGFs. To understand better the role(s) of IGFBPs in prostate growth and malignancy, we examined the regulation of IGFBPs in PC-3 cells, a human prostatic adenocarcinoma epithelial cell line that is androgen-insensitive. Both transforming growth factor-beta (TGF beta) and retinoic acid (RA), known inhibitors of cellular proliferation, significantly changed the IGFBP profile in PC-3 cells. In cells that were treated with transforming growth factor beta-2 (TGF-beta 2) (0.5-10 ng/mL), IGFBP-3, and IGFBP-5 protein and mRNA increased in a time- and dose-dependent manner. At 10 ng/mL TGF-beta, IGFBP-3, and IGFBP-5 protein concentrations were 14- and 9-fold, respectively, over that of controls. Cells treated with RA (0-1 microM) also showed a time- and dose-dependent increase in IGFBP-3 protein and mRNA levels. However, in contrast to TGF-beta 2, high concentrations of RA (1 microM) negatively regulated IGFBP-5 expression, with IGFBP-5 mRNA levels downregulated to 20% of that of the control, and protein levels were decreased by 50%. Since both TGF-beta and RA increased IGFBP-3 expression and both are known to inhibit prostate cell growth, we speculate that the inhibition of growth is mediated, at least in part, by IGFBP-3. PMID- 9368679 TI - Estrogen can protect splenocytes from the toxic effects of the environmental pollutant 4-tert-octylphenol. AB - Four-tert-octylphenol (OP), an environmental pollutant, exerts apoptotic effects on cultured mouse splenocytes. Although OP binds to estrogen receptors, these apoptotic effects are not exerted by 17 beta-estradiol (E). It remained possible that OP might bind to estrogen receptors and subsequently exert apoptotic effects not exerted by E after it binds to the same receptors. It also remained possible that E-primed splenocytes might respond to OP differently than splenocytes not exposed to E. Thus, we investigated OP and E interactions on the viability of mouse splenocytes in culture. The total number of splenocytes (cells stained and not stained with trypan blue) was not altered or altered slightly after incubation with any agent for 24 h. Incubation of splenocytes in medium containing 5 x 10(-5) or 5 x 10(-7) M OP decreased the percentage of viable cells by only approx 47% and 25%, respectively. The addition of 0.8 x 10(-5) to 0.8 x 10(-9) M E to cultures was without effect or decreased the percentage of viable cells by only approx 5%. The addition of these concentrations of E simultaneously with or at 2 h after the addition of 5 x 10(-5) M or 5 x 10(-7) M OP to cultures did not interfere with the OP-induced decreases in cell viability. By contrast, incubation of splenocytes in medium containing E for 2 h prior to the subsequent addition of either dose of OP blocked the OP-induced decreases in cell viability in a dose-response manner. There was a marked reduction in the percentage of viable cells (70%) when splenocytes were incubated with 0.5 x 10(-5) M dexamethasone. The addition of 0.8 x 10(-5) M E at 2 h prior to the addition of dexamethasone did not prevent the decreased cell viability. Incubation of cells in medium with 0.8 x 10(-5) M testosterone caused a small decrease in splenocyte viability similar to that observed with E. However, unlike E, the addition of testosterone at 2 h prior to the addition of 5 x 10(-5) M OP did not prevent the OP-induced decrease in cell viability. These data suggest the presence of estrogen receptors in some splenocytes. They also suggest that if OP binds to these estrogen receptors or other receptors in the absence or initial presence of E, the resulting effect is toxic to the cells. By contrast, exposure of splenocytes to E prior to their exposure to OP can prevent the toxicity of OP. PMID- 9368680 TI - Effects of ovariectomy and hypothalamic-pituitary disconnection on amounts of steroidogenic factor-1 mRNA in the ovine anterior pituitary gland. AB - Steroidogenic factor-1 (SF-1) is a transcription factor involved in regulation of steroidogenic enzymes. Recent evidence indicates that SF-1 is also important in the anterior pituitary gland, where it may influence gene expression in gonadotropes. We isolated a cDNA encoding ovine SF-1 and demonstrated that the SF 1 gene is expressed in the anterior pituitary gland of sheep. SF-1 transcripts and luteinizing hormone (LH) were colocalized in gonadotropes by in situ hybridization and immunohistochemistry, respectively. To test the hypothesis that GnRH stimulates pituitary expression of ovine SF-1 mRNA, ewes were ovariectomized to increase endogenous secretion of GnRH. Compared to ovary-intact ewes, ovariectomy resulted in three- and fourfold increases in steady-state amounts of mRNA encoding SF-1 and LH beta subunit, respectively. In ovariectomized ewes in which delivery of GnRH to the anterior pituitary gland was prevented by hypothalamic-pituitary disconnection (HPD), steady-state amounts of mRNA encoding SF-1 and LH beta-subunit were decreased. These results provide evidence that pituitary SF-1 gene expression in sheep is regulated by GnRH. Coordinate regulation of mRNAs encoding SF-1 and LH beta-subunit raises the possibility that SF-1 may be an important transcriptional regulator of LH beta-subunit gene expression in ovine gonadotropes. PMID- 9368682 TI - Dehydroepiandrosterone administration reverses the inhibitory influence of aging on gonadotrophin-releasing hormone gene expression in the male and female rat brain. AB - Dehydroepiandrosterone (DHEA) has been shown to exert a beneficial influence on some aging-associated deficits in rodents. It is well documented that in the rat, aging is associated with a decline in reproductive functions. In order to evaluate the effect of DHEA on GnRH gene expression in aged animals, we have studied the effect of 2.5-d administration of DHEA to young (50-54 d of age) and aged (18 mo of age) rats of both sexes. In the young males, DHEA induced an 18% reduction in the hybridization signal. In the aged animals, the mRNA levels were 10% lower than those observed in the young rats. DHEA completely restored the mRNA levels when compared to those detected in young male animals. In the young female, DHEA produced a 11% increase in GnRH mRNA, whereas, in the aged animals, hybridization signal was decreased by 28%. DHEA administration to aged females induced a 33% increase in the amount of mRNA, thus completely reversing the influence of aging. These results indicate that the decrease in GnRH gene expression which is likely involved in the loss of reproductive functions in aged rats can be totally reversed by a short term administration of DHEA which restored the GnRH neuronal activity. They also suggest that DHEA might play a role in the prevention and/or improvement of some deficits associated with aging through stimulation of GnRH biosynthesis. PMID- 9368681 TI - Platelet derived growth factor stimulates chondrocyte proliferation but prevents endochondral maturation. AB - Platelet-derived growth factor (PDGF) is a cytokine released by platelets at sites of injury to promote mesenchymal cell proliferation. Since many bone wounds heal by endochondral bone formation, we examined the response of chondrocytes in the endochondral lineage to PDGF. Confluent cultures of rat costochondral resting zone cartilage cells were incubated with 0-300 ng/mL PDGF-BB for 24 h to determine whether dose-dependent changes in cell proliferation (cell number and [3H]-thymidine incorporation), alkaline phosphatase specific activity, [35S] sulfate incorporation, or [3H]-proline incorporation into collagenase-digestible protein (CDP) or noncollagenase-digestible protein (NCP), could be observed. Long term effects of PDGF were assessed in confluent cultures treated for 1, 2, 4, 6, 8, or 10 d with 37.5 or 150 ng/mL PDGF-BB. To determine whether PDGF-BB could induce resting zone chondrocytes to change maturation state to a growth zone chondrocyte phenotype, confluent resting zone cell cultures were treated for 1, 2, 3, or 5 d with 37.5 or 150 ng/ml PDGF-BB and then challenged for an additional 24 h with 1,25-(OH)2D3. PDGF-BB caused a dose-dependent increase in cell number and [3H]-thymidine incorporation at 24 h. The proliferative effect of the cytokine decreased with time. PDGF-BB had no effect on alkaline phosphatase at 24 h, but at later times, the cytokine prevented the normal increase in enzyme activity seen in post-confluent cultures. This effect was primarily on the cells and not on the matrix. PDGF-BB stimulated [35S]-sulfate incorporation at all times examined, but had no effect on [3H]-proline incorporation into either the CDP or NCP pools. Thus, percent collagen production was not changed. Treatment of the cells for up to 5 d with PDGF-BB failed to elicit a 1,25-(OH)2D3 responsive phenotype typical of rat costochondral growth zone cartilage cells. These results show that committed chondrocytes can respond to PDGF-BB with increased proliferation. The effect of the cytokine is to enhance cartilage matrix production, but at the same time to prevent progression of the cells along the endochondral maturation pathway. PMID- 9368683 TI - The effects of estradiol-17 beta infusion into fetal sheep in late gestation. AB - Activation of the hypothalamic-pituitary-adrenal (HPA) axis of fetal sheep during late gestation is associated with increases in plasma concentrations of adrenocorticotropic hormone (ACTH) and cortisol, and ultimately results in parturition. However, the mechanisms contributing to the concurrent increases in ACTH and cortisol are unclear. Plasma estradiol-17 beta (E2) concentrations increase progressively in the prepartum ovine fetus, and we hypothesized that E2 may influence HPA activity by affecting either basal and/or hypoxemia-stimulated ACTH release. We examined potential mechanisms, including altered expression of pro-opiomelanocortin (POMC) in fetal pituitary corticotrophs, and changes in corticosteroid binding globulin (CBG) and/or the enzymes 11 beta hydroxy steroid dehydrogenase (11 beta HSD)-1 or 11 beta HSD-2 in liver and placenta, that could alter negative feedback control. We infused fetal sheep at 127 d of gestation with either E2 (100 micrograms/24 h) or saline for 100 h. Fetal arterial blood samples were collected at 8 h intervals during the infusion of E2 or saline (n = 4), for measurement of basal plasma ACTH and cortisol concentrations, as well as plasma corticosteroid binding capacity (CBC). Placenta and fetal liver samples were collected at 100 h for measurement of placental 11 beta HSD-1 and 11 beta HSD-2 mRNA and hepatic CBG and 11 beta HSD-1 mRNA, by Northern blotting. Fetal pituitary samples were collected for measurement of POMC mRNA by in situ hybridization. In a separate experiment, fetuses were exposed to 2 h of hypoxemia at 75 h of E2 or saline infusion (n = 4), and fetal arterial blood samples were collected during the period of hypoxemia for measurement of plasma ACTH and cortisol concentrations. E2 infusion had no effect on basal plasma concentrations of ACTH or total cortisol, or on the stimulated levels of ACTH or total cortisol achieved in response to hypoxemia. Basal fetal pituitary POMC mRNA also did not change significantly with E2 infusion. No significant increases were observed in plasma CBC during E2 administration. However, hepatic CBG and 11 beta HSD-1 mRNA were significantly elevated in the livers of E2-treated fetuses. Placental 11 beta HSD-1 mRNA; but not 11 beta HSD-2 mRNA was increased by E2 treatment. These data do not support a direct effect of exogenous E2 at the level of basal or hypoxemia-stimulated ACTH output, but suggest that elevated E2 concentrations may alter the expression of genes encoding proteins implicated in tonic regulation of fetal HPA function. PMID- 9368684 TI - Calcium-lowering action of glucocorticoids in adrenalectomized parathyroidectomized rats. Specificity and relative potency of natural and synthetic glucocorticoids. AB - The specificity and potency of glucocorticoids to lower serum calcium (Ca) in rats after parathyroidectomy (PTX) and adrenalectomy (ADX) were examined. Rats fasted overnight were given sc injections of various steroids immediately after the operations. The fall in serum calcium 5 h after PTX-ADX in rats given hypocalcemic doses of corticosterone was compared to that after injection of a test steroid. At high doses, progesterone, estradiol, testosterone, and aldosterone were inactive, whereas glucocorticoids were consistently hypocalcemic. These results indicate that the Ca-lowering effect is specific for steroids with glucocorticoid activity. Potency estimates were made by comparing the dose-response of natural and synthetic glucocorticoids to that of corticosterone, the major glucocorticoid in rats. The mean potency of hydrocortisone was 8.2 times that of corticosterone. Prednisolone was about 9.6, triamcinolone 33, betamethasone 109, and dexamethasone 301 times as potent as corticosterone. Thus, the use of the calcium-lowering action as a bioassay has provides a specific and rapid in vivo method to compare potencies of glucocorticoids consistent with those obtained by anti-inflammatory and glycogen deposition assays. The importance of this interesting calcitonin-like action of glucocorticoids in normal physiology of calcium metabolism is not yet established. PMID- 9368685 TI - Insulin antibodies and hypoglycemia in diabetic patients. Can a quantitative analysis of antibody binding predict the risk of hypoglycemia? AB - We report a noninsulin-dependent diabetes mellitus (NIDDM) patient with spontaneous, severe hypoglycemic reactions and the presence of insulin antibodies. He had a remote antecedent history of beef-pork insulin therapy as well as exposure to hydralazine. Detailed insulin binding kinetic studies were performed in this patient as well as in six other insulin-treated diabetic patients with anti-insulin antibodies (three with and three without an obvious cause of hypoglycemia). Sera from the current patient and five of the six other diabetic patients (one NIDDM, four IDDM) revealed two types of binding sites: high-affinity with low capacity (Kd, 0.4-12.4 x 10(-9) mol/L; binding capacity, 0.6-659 mU/L) and low-affinity with high capacity (Kd, 0.3 to 35.7 x 10(-7) mol/L; binding capacity; 202-113,680 mU/L). One NIDDM patient had only high affinity antibodies (Kd, 22.9 x 10(-9) mol/L; binding capacity of 78 mU/L). Type of diabetes mellitus, insulin antibody titers or their binding capacities, insulin levels (total, bound, or free), and bioavailable insulin were not related to hypoglycemic reactions. Two calculated values by the method described tended to discriminate patients with and without hypoglycemia. The calculated amount of low-affinity antibody bound insulin ranged from 69.4-2090 mU/L vs < 4-70.6 mU/L in patients with and without hypoglycemia, respectively. The best discrimination was afford by the percent saturation of low-affinity binding sites; values were clearly higher in the patients with hypoglycemia (2.5-34.4%) than in those without hypoglycemia (not detectable, 0.06, 0.15%). Consideration of the possible drug-associated insulin antibody formation in insulin-treated diabetics and the novel quantitative analysis of the antibody binding kinetics should prove helpful in evaluating patients with high insulin antibody titers and assessing the risk of hypoglycemia. PMID- 9368686 TI - CRH and AVP-induced changes in synthesis and release of ACTH from the ovine fetal pituitary in vitro: negative influences of cortisol. AB - During late gestation in sheep, fetal plasma adreno-corticotrophin (ACTH) and cortisol levels increase, and these are associated with increased pro opiomelanocortin (POMC) mRNA levels in the anterior pituitary. Corticotrophin releasing hormone (CRH) and vasopressin (AVP) are the primary hypophysiotrophic factors regulating ACTH secretion from the fetal sheep pituitary corticotroph, but previous reports with term fetal tissue have failed to show effects on levels of POMC mRNA. The objectives of the present study were to establish the effects of CRH and AVP on both synthesis and secretion of ACTH before term, and to determine how cortisol affects these responses. Fetal pituitaries were removed at d 138 of gestation (term approximately d 147), the anterior pituitary was separated, and the cells dispersed and placed in monolayer tissue culture. After 4 d, cells were treated for 18 h with several different concentrations (10(-6) 10(-9) M) and combinations of CRH, AVP, and cortisol. Following incubation, the medium was removed for ACTH analysis, and the cells fixed for POMC mRNA measurement and immunoreactive (ir)-ACTH localization. Separately, CRH and AVP significantly (p < 0.05) stimulated ACTH secretion in a dose-dependent manner. Simultaneous treatment of maximally stimulating levels of CRH and AVP augmented (p < 0.05) the output of ACTH. Cortisol did not affect basal (nonstimulated) ACTH output, but attenuated the neuropeptide-induced increases in ACTH secretion. This effect of cortisol was more pronounced in cells treated with CRH than in cells treated with AVP. POMC mRNA levels were increased by both CRH and AVP treatments in a dose-dependent manner, though there was no further increase in POMC mRNA when CRH and AVP were added together. Cortisol attenuated (p < 0.05) the neuropeptide-induced increases in POMC mRNA, though AVP-stimulated POMC mRNA levels were significantly higher than in cells treated with cortisol alone. Cortisol failed to alter non-stimulated POMC mRNA levels. We conclude that in late gestation: 1) Fetal pituitary corticotrophs respond to CRH and AVP by increasing POMC mRNA levels and ACTH secretion 2) AVP is more potent than CRH at the level of ACTH secretion, but not POMC transcription 3) Cortisol attenuates the synthetic and secretory responses to CRH and AVP, but has little effect in the non-stimulated state. PMID- 9368688 TI - Thyroxine binding to transthyretin Met 119. Comparative studies of different heterozygotic carriers and structural analysis. AB - The majority of the known transthyretin (TTR) variants are associated with amyloidosis, but there are also variants associated with euthyroid hyperthyroxinemia and others are apparently nonpathogenic. TTR Met 119 is a nonpathogenic variant found to be frequent in the Portuguese population. Previous studies on thyroxine (T4) binding to semi-purified TTR from heterozygotic carriers of TTR Met 119, reported by us and other groups, revealed different results. Therefore, to further characterize T4 binding to TTR Met 119 we performed T4-TTR binding studies in homotetrameric-recombinant TTR Met 119 variant and normal TTR. We also studied T4 binding to TTR purified from serum of different heterozygotic carriers of TTR Met 119 including compound heterozygotic individuals carriers of a TTR mutation in the other allele. We observed an increased T4 binding affinity to TTR Met 119 from heterozygotic individuals and compound heterozygotes and this effect of increasing T4 binding affinity was consistent and independent from the mutation present in the other allele. Recombinant homotetrameric TTR Met 119 and heterotetrameric protein from heterozygotic carriers of TTR Met 119 presented similar T4 binding affinity demonstrating the increased T4 binding affinity of TTR Met 119. X-ray crystallography studies performed on the recombinant TTR Met 119 variant revealed structural alterations mainly at the level of residue Leu 110 allowing a closer contact between the hormone and the mutant protein. These results are consistent with the observed T4 binding results. PMID- 9368687 TI - Progesterone-dependent decidualization of the human endometrium is mediated by cAMP. AB - Progesterone is a key factor in regulating endometrial cell decidualization, but the signal transduction pathways involved in mediating the effects of progesterone are not known. A role of the cAMP pathway in decidualization has been suggested by in vitro studies demonstrating that cAMP agonists can stimulate decidualization, in the absence of sex steroids. In this article, we have used an in vitro culture model of progesterone-dependent decidualization of human endometrial stromal cells to examine whether progesterone-induced decidualization is associated with activation of the cAMP signal transduction pathway in which the prolactin gene expression is a marker of decidualization. Following a lag period of approx 3 d, progesterone induced prolactin secretion and elevated intracellular cAMP levels. By d 15, cAMP and prolactin levels were approx 10- and 60-fold greater, respectively, than those on d 3. Changes in cAMP levels showed a positive correlation with prolactin secretion. Prostaglandin E2 (PGE2), which enhances progesterone-dependent decidualization, also increased both prolactin secretion and cAMP levels approx two- to fourfold on d 15 compared with d 3, whereas PGE2 alone, which does not induce decidualization, did not stimulate prolactin secretion or intracellular cAMP accumulation. Conversely, all-trans retinoic acid, which attenuates progesterone-dependent decidualization, significantly (p < 0.05) decreased both prolactin secretion and cAMP levels. Furthermore, the protein kinase A (PKA) inhibitor, 8-bromoadenosine-3',5'-cyclic monophosphorothioate, significantly (p < 0.05) suppressed progesterone-dependent prolactin expression. Since activation of the PGE2 receptor subtype EP2 stimulates adenylate cyclase, reverse transcription-polymerase chain reaction (RT PCR) analysis of endometrial cells was undertaken. Expression of EP2 mRNA was induced in cells treated with progesterone and estradiol alone or with PGE2, compared with untreated controls. The data suggest that the cAMP signal transduction cascade is activated during progesterone-dependent decidualization. PMID- 9368689 TI - The effect of tumor necrosis factor-alpha and cAMP on induction of AP-1 activity in MA-10 tumor Leydig cells. AB - The immunostimulant tumor necrosis factor-alpha (TNF alpha), produced by monocytes/macrophages in response to inflammatory disorders, regulates gene expression in part through induction of mitogen-activated protein kinases (MAPKs), including the stress-activated protein kinase (SAPK) (c-Jun N-terminal kinase [JNK]) and the extracellular signal-regulated kinases (ERKs). In testicular Leydig cells, the induction of steroidogenesis by cAMP is inhibited by TNF alpha. To examine the potential mechanisms governing the mutual inhibition between cAMP and TNF alpha in Leydig cells, the intracellular signaling pathways that contribute to AP-1-dependent gene expression were examined in the mouse MA 10 Leydig cell line. TNF alpha induced SAPK activity sixfold at 15 min, and the PKC inhibitor calphostin C reduced the induction of SAPK by 30%. cAMP induced SAPK activity twofold but reduced TNF alpha-induced SAPK activity. ERK activity was inhibited by both cAMP and TNFa. TNFa increased c-Jun protein, but only weakly induced FOS proteins (c-Fos, FosB, Fra-1, and Fra-2) whereas cAMP increased the abundance of several FOS proteins (c-Fos, FosB, Fra-1, and Fra-2), with little effect on c-Jun levels. AP-1 binding activity, assessed using electrophoretic mobility shift assays, was increased twofold by TNF alpha and fivefold by cAMP. Cyclic AMP alone induced AP-1-responsive reporter (p3TPLUX) activity threefold after 2 h with peak effect of 4-fold at 4 hr. AP-1 reporter was not induced by TNF alpha alone but in the presence of cAMP, TNF alpha induced AP-1 reporter activity 12-fold. In conclusion, TNF alpha and cAMP induce distinct components that separately contribute to the modulation of AP-1 activity in MA-10 cells. PMID- 9368691 TI - XXVI Colloquium of The Society for Experimental Neuroendocrinology and 8th meeting of the European Neuroendocrine Association. Marseille, France, 9-13 September 1997. Abstracts. PMID- 9368690 TI - Dopamine D2 receptor stimulation alters G-protein expression in rat pituitary intermediate lobe melanotropes. AB - Stimulation of dopamine D2 receptors inhibits melanotrope pro-opiomelanocortin (POMC) biosynthesis and alpha-melanocyte-stimulating hormone (MSH) secretion. These effects are mediated by G-protein alpha i- and alpha o-subunits and are reversed by stimulating receptors linked to activation of G alpha s protein. Melanotrope activity is increased by haloperidol, a D2 receptor antagonist, and decreased by bromocriptine, a D2 receptor agonist. Both the short and long isoforms of the D2 receptor mRNA and protein increase following chronic haloperidol treatment. After chronic bromocriptine treatment the short isoform is downregulated, whereas the long isoform is upregulated. Our hypothesis is that specific G protein alpha- subunits alter in pattern of expression similarly to the receptor isoforms. Using immunohistochemistry and in situ hybridization, this study examined changes in G alpha i, G alpha o, and G alpha s protein and mRNA expression following chronic treatments with bromocriptine or haloperidol. G alpha i3 and G alpha o immunoreactivities increased following bromocriptine treatment, whereas G alpha s and G alpha i1/2 did not change. Gs immunoreactivity increased after haloperidol treatment, whereas G alpha i1/2, G alpha i3, and G alpha o did not change. G alpha i and G alpha o mRNA increased following bromocriptine and decreased following haloperidol treatments, whereas the inverse results were observed with G alpha s mRNA. These results suggest D2 receptor activation can specifically increase G alpha i3 and G alpha o expression, and D2 receptor blockade increases G alpha s expression. PMID- 9368692 TI - Physiology Society, 65th Meeting. Prague, 16-20 September 1997. Abstracts. PMID- 9368693 TI - 6th International Neuromuscular Meeting. Paris, France, 22-24 August 1997. Abstracts. PMID- 9368694 TI - [45th Scientific Session of The Japanese College of Cardiology. Sapporo, September 25-27, 1997. Abstracts]. PMID- 9368696 TI - Joint meeting of the British Association for Psychopharmacology and the Canadian College for Neuropsychopharmacology. Cambridge, United Kingdom 13-17 July 1997. Abstracts. PMID- 9368695 TI - British Pharmaceutical Conference 1997, 134th meeting. Scarborough, United Kingdom, September 15-18, 1997. Abstracts. PMID- 9368697 TI - VIth Asian-Pacific Symposium on Cardiac Pacing and Electrophysiology (ASPE). New Delhi, India, October 25-28, 1997. Abstracts [abstract no. 104 retracted in: Pacing Clin Electrophysiol 1998 Mar;21(3):634]. PMID- 9368698 TI - Quantification of rigidity and tremor activity in rats by using a new device and its validation by different classes of drugs. AB - Subjective techniques employed for measuring skeletal muscle tone and tremor, leading symptoms of several diseases, have certain limitations. Objective methods are usually more sensitive and accurate. The equipment developed by the authors allows the objective and rapid measurement of experimentally induced rigidity and tremor in the same small laboratory animal (rat). The present method considerably reduces the number of animals needed to investigate the activity of drugs, especially when compounds should be screened. Due to the greater sensitivity of the equipment, doses of reserpine and oxotremorine which do not cause any postural, autonomic or parasympathetic symptoms can be used to induce muscular rigidity and tremor. Therefore, not only the number of animals but also their stress can be reduced. It was possible to differentiate the oxotremorine-induced tremor from the spontaneous motor activity and to determine qualitative differences in tremor caused by antitremor agents. A number of clinically effective muscle relaxants and antiparkinsonian drugs were examined in this model in order to determine its utility. PMID- 9368699 TI - Drug dependence study on vigabatrin in rhesus monkeys and rats. AB - The dependence potential of vigabatrin (gamma-vinyl GABA; R(-)/S(+)-4-amino-5 hexenoic acid, CAS 60643-86-9, MDL 71,754) was assessed in rhesus monkeys and rats. In the test of cross physical dependence potential, morphine- and barbital dependent monkeys were both withdrawn from the respective drugs and the ability of vigabatrin to suppress the withdrawal signs was assessed. In morphine dependent monkeys, subcutaneous doses of vigabatrin at 256 and 1000 mg/kg did not suppress withdrawal signs while subcutaneous doses of codeine phosphate at 4 and 8 mg/kg clearly suppressed the withdrawal signs. In barbital-dependent monkeys, subcutaneous and intravenous dose of vigabatrin, both at 1000 mg/kg, did not suppress the withdrawal signs, while intragastric doses of diazepam at 8 and 16 mg/kg clearly suppressed them. Thus, while the cross-physical dependence potential of codeine/morphine and of diazepam/barbital was clearly observable, vigabatrin appeared to have no such potential. In the test of physical dependence producing potential with the drug-admixed food method in rats, vigabatrin and diazepam were given to rats mixed with food for 28 days in an increasing dosage schedule, followed by feeding a drug-free diet to observe withdrawal signs for 7 days. Upon withdrawal, no decrease in food intake or body weight was observed in the vigabatrin-treated groups, and the gross condition of the animals did not differ from that in the control group. In contrast, food intake and body weight decreased markedly in the diazepam group, and most rats showed hyperreactivity to external stimuli. Thus, while the physical dependence-producing potential of diazepam was clearly demonstrated, such potential was not shown with vigabatrin. In the test of reinforcing effect, 4 monkeys were allowed to self-administer pentobarbital at 1 mg/kg/infusion, or vigabatrin at 16, 32, and 64 mg/kg/infusion, intravenously through an indwelling catheter. Each drug was preceded and followed by saline self-administration for at least 7 days. Active self-administration of pentobarbital was observed in all monkeys tested, while the self-administration rate of vigabatrin did not differ from saline. Thus, while the reinforcing effect of pentobarbital was clearly observed, such effect was not observable with vigabatrin. Based on these results, it was considered that vigabatrin was devoid of dependence potential. PMID- 9368700 TI - Nitric oxide as a regulator of prostacyclin synthesis in cultured rat heart endothelial cells. AB - The effects of nitric oxide (NO) and its second messenger cyclic guanosine monophosphate (cGMT) on prostacyclin (PGI2) synthesis were studied in cultured rat heart endothelial cells using three different non-enzymatic nitric oxide releasing substances as well as inhibitors of nitric oxide synthase and of soluble guanylate cyclase. Production of prostacyclin, measured as 6-keto prostaglandin F1 alpha (6-keto-PGF1 alpha), was stimulated up to 1.7 fold in endothelial cells treated with the NO donors SIN-1 (3-morpholino sydnonimine), GEA 3162 (3-aryl-substituted oxatriazole imine) and GEA 3175 (3-aryl-substituted oxatriazole sulfonyl), chloride). In each case the synthesis of cGMP increase as much as 40-100 fold. An inhibitor of NO synthase, NG-nitro-L-arginine methyl ester (L-NAME), decreased the basal production of 6-keto-PGF1 alpha in non stimulated endothelial cells, an effect that could be reversed by the NO donors SIN-1, GEA 3162 and GEA 3175. cGMP formation in the L-NAME treated endothelial cells was unaltered. The guanylate cyclase inhibitors, methylene blue (100 mumol/l) and LY83583 (100 mumol/l), caused a 1.5-10 fold increase in 6-keto-PGF1 alpha production while NO-donor-stimulated endothelial cGMP production was decreased by 10 to 90%. However, when SIN-1 was used as a stimulant, LY83583 had no significant effect on the production of cGMP. These findings support the hypothesis that NO stimulates prostacyclin production directly by activating cyclooxygenase. The results also suggest that NO could have an indirect effect on prostacyclin production via cGMP. PMID- 9368701 TI - Effects of the new angiotensin receptor antagonist dipotassium (Z)-2-[[5-ethyl-3 [2'-(1H-tetrazol-5-yl)biphenyl-4-yl] methyl-1,3,4-thiadiazoline-2 ylidene]aminocarbonyl]-1-cy clopentencarbox ylate on experimental cardiac hypertrophy and acute left ventricular failure. AB - The cardiovascular effects of dipotassium (Z)-2-[[5-ethyl-3-[2'-(1H-tetrazol-5 yl)biphenyl-4-yl] methyl-1,3,4-thiadiazoline-2-ylidene]aminocarbonyl]-1-cyc lopentencarboxylate CAS 169328-25-0, KRH-594), a new angiotensin II type 1 (AT1) receptor antagonist, on pressure-overload cardiac hypertrophy in rats and on acute left ventricular failure in dogs were investigated. In rats with a 2-week abdominal aorta constriction, left ventricular weight (LVW) and systolic blood pressure (SBP) were significantly greater than in sham-operated rats. Oral administration of KRH-594 (10 or 30 mg/kg/day for 2 weeks) reduced the increases in both LVW and SBP. Another AT1 receptor antagonist, candesartan cilexetil (1 or 3 mg/kg/day for 2 weeks), also prevented this type of cardiac hypertrophy. In anesthetized dogs with a 60-min coronary ligation, left ventricular end-diastolic pressure (LVEDP) and total peripheral resistance (TPR) were raised, whereas the maximum first derivative of left ventricular pressure and cardiac output were both decreased. Intravenous administration of KRH-594 (3 mg/kg) significantly attenuated the increases in both LVEDP and TPR after coronary ligation. These results suggest that KRH-594, by reducing the cardiac afterload, may ameliorate pressure-overload cardiac hypertrophy in rats and produce an improvement in the hemodynamic status of dogs with acute left ventricular failure. PMID- 9368702 TI - Antithrombotic effects of 3-([1:1',2':1"]-3'-terphenyl)propanol in animals. AB - 3-([1:1',2':1"]-3'-Terphenyl)propanol (CAS 186835-06-3, F050) and acetylsalicylic acid (ASA) inhibited platelet aggregation induced by CaCl2, arachidonic acid, collagen, adenosine diphosphate (ADP) and thrombin in guinea pigs, rabbits and rats in vitro. However, F050 had a wider spectrum of actions than ASA. Orally administered F050 inhibited platelet aggregation ex vivo. F050 significantly reduced the thrombus formation in the extracorporeal circulation thrombosis model in guinea pigs. It inhibited erythrocyte hemolysis induced by hypotonic NaCl, while ASA did not. F050, but not ASA, inhibited increases in platelet [CA2+]i caused by thrombin in guinea pigs. F050 is a parent compound that will facilitate the development of an orally active drug for the treatment of thrombotic diseases. PMID- 9368703 TI - Effect of acarbose and simultaneous antacid therapy on blood glucose. AB - In a single-centre, placebo-controlled, clinical study, the influence of an antacid containing magnesium hydroxide and aluminium hydroxide (Maalox 70; 10 ml) on the pharmacodynamics of the oral antidiabetic drug acarbose (Glucobay 100, Bay g 5421, CAS 56180; 100 mg) was tested in 24 healthy male volunteers. The drugs were given alone or in combination and were compared with placebo. Volunteers were randomized into four different treatment groups. The daily medication over 4 days was 1 x 1 placebo tablet, or 1 x 1 tablet containing 100 mg acarbose, or 1 x 1 tablet containing 100 mg acarbose plus 10 ml antacid suspension, or 1 x 1 placebo tablet plus 10 ml antacid suspension, interrupted by wash-out phases of 6 10 days between successive treatments. Efficacy was assessed on the basis of postprandial blood glucose and serum insulin levels after administration of 75 g sucrose, and was measured as maximal concentrations and 'area under the curve' (0 4 h). No influence of the antacid on the blood glucose and insulin-lowering effect of acarbose could be detected. Hence, there does not appear to be a significant interaction between acarbose and the antacid tested. Antacids similar to that tested do not need to be classified as a contraindication when used in combination with acarbose. PMID- 9368704 TI - Eosinophil chemotaxis induced by several biologically active substances and the effects of apafant on it in vitro. AB - Chemotaxis of guinea pig eosinophils induced by various stimuli in use of a modified Boyden chamber technique in vitro and the effect of a platelet activating factor (PAF) antagonist, apafant (CAS 105219-56-5, WEB 2086 BS), on it were examined. The eosinophils were obtained by bronchoalveolar lavage from the animals treated by i.v. injection with Sephadex G-200 and purified by Percoll density gradient centrifugation. PAF significantly and potently induced the chemotaxis at a broad range of 10(-17) to 10(-7) mol/l, where no concentration dependency was observed. Leukotriene B4 also induced the chemotaxis in a concentration-dependent manner at 10(-14) to 10(-12) mol/l and the enhanced migration was not declined until 10(-7) mol/l. Interleukin-5 (IL-5), IL-8 and regulated on activation normal T expressed and secreted (RANTES) only modestly enhanced the chemotaxis in some concentrations at 10(-13) to 10(-7) mol/l with or without significance and with no concentration-dependency while formyl-methionyl leucyl-phenylalanine (FMLP), a known chemoattractant, increased the migration at 10(-7) to 10(-5) mol/l. Apafant at 10(-8) to 10(-6) mol/l strongly and concentration-dependently inhibited 10(-8) mol/l PAF-induced chemotaxis. However, the drug showed nominal or no influences on their chemotaxis stimulated by the other agonists, at the concentrations of which the enhanced migration was observed. From these results, it is concluded that IL-5, IL-8 and RANTES, different from PAF and LTB4, are not potent stimuli for the eosinophil chemotaxis and that apafant is a selective antagonist of PAF, which is expected to be therapeutically effective for PAF-associated diseases including bronchial asthma. PMID- 9368705 TI - Pharmacokinetic and pharmacodynamic evaluation of central effect of the novel antiallergic agent betotastine besilate. AB - Betotastine besilate (betotastine CAS 125602-71-3, TAU-284) is a novel antiallergic agent with histamine H1 receptor antagonistic activity. As the classical antihistamines are known to produce drowsiness, the present study was conducted to assess a possible influence of betotastine on the central nervous system (CNS). Measurement of the drug concentration in brain and plasma after i.v. administration revealed that betotastine, as well as cetirizine and epinastine, poorly penetrate into the CNS, while terfenadine do so slightly more and ketotifen remarkably more. In vitro receptor binding assays demonstrated that betotastine is a highly specific histamine H1 receptor ligand, having no significant binding affinity for histamine H3, adrenergic alpha 1, alpha 2, beta, dopamine D2L, serotonin 5-HT2, muscarinic, and benzodiazepine receptors. On global behavior of mice, oral administration of betotastine did not produce any marked changes at the doses of 100-1000 mg/kg, but suppressed huddling behavior at 1000 mg/kg and caused slight mydriasis at 300 mg/kg and more. Betotastine did not significantly affect spontaneous motor activity (SMA) and hexobarbital induced anesthesia in mice up to 300 mg/kg p.o. In the sleep-wakefulness pattern of cats, it reduced the total duration of sleep at 10 mg/kg p.o., but did not show significant effect at 30 and 100 mg/ kg p.o. Cetirizine showed a similar profile as betotastine in these experiments, whereas ketotifen and epinastine induced sedative signs or toxic symptoms in lower doses, and terfenadine affected SMA and the anesthesia at a high dose. These results suggest the very low liability of betotastine to produce sedative side-effect in a therapeutic dose range. PMID- 9368707 TI - Cholecystokinin antagonistic activities of loxiglumide. AB - Cholecystokinin (CCK) antagonistic activities of loxiglumide ((+/-)-4-(3,4 dichlorobenzamido)-N-(3-methoxypropyl)-N-pentylgl utaramic acid, CR1505, CAS 107097-80-3) were investigated in the gastrointestine and gallbladder in vivo. Intravenous administration of loxiglumide antagonized the CCK-induced reduction of gastric emptying in rats, acceleration of intestinal transport in mice, increase in ileal motility in rabbits, gallbladder contraction in guinea pigs and acceleration of gallbladder emptying in mice. Orally administered loxiglumide also antagonized the CCK-induced gallbladder emptying in mice. Furthermore, egg yolk-stimulated gallbladder emptying in mice was also inhibited by loxiglumide, indicating that this agent antagonizes not only exogenous but also endogenous CCK. These results demonstrate that loxiglumide is an intravenously and orally effective, potent CCK antagonist. PMID- 9368706 TI - Mechanism of the antihyperlipaemic activity and pharmacokinetics of 2 chloromethyl-5,6,7,8-tetrahydrobenzo(b)thieno[2,3-d]pyrimidin-4(3H)-o ne. AB - The pharmacokinetics and the mechanism of action of the antihyperlipaemic compound 2-chloromethyl-5,6,7,8-tetrahydrobenzo(b)thieno[2,3-d]pyrimidin-4(3H)-on e (CAS 89587-03-3, LM-1554) have been studied. Serum concentrations were determined by reverse phase HPLC using methanol : water (60 : 40) as the solvent system. The results of pharmacokinetic studies suggest that the compound LM-1554 is poorly absorbed from the gastrointestinal tract after the oral administration in dogs and rabbits. The volume of distribution (Vd) was found to be low. The poor bioavailability (3-4%) and low volume of distribution of the compound LM 1554 suggest the gastrointestinal tract as the site of action for the antihyperlipaemic activity. This hypothesis is substantiated by the observations that the compound was found active in rabbits only when administered orally and found inactive by the parenteral route. Further, the cholesterol levels were found to increase in blood samples collected from the portal vein after oral administration of cholesterol in coconut oil to rats. This increase was found to be prevented by the compound LM-1554. In conclusion, the compound LM-1554 has a potential to be developed as an antihyperlipaemic agent. The mechanism of action of the compound LM-1554 appears to consist in the inhibition of cholesterol absorption in the gastrointestinal tract. PMID- 9368708 TI - Synthesis and antibacterial activity of 5-aryl-2-[(alpha-chloro-alpha phenylacetyl/alpha-bromopropionyl)amino]- 1,3,4-oxadiazoles and 2-[(5-aryl-1,3,4 oxadiazol-2-yl)imino]-5-phenyl/methyl-4-thiazolidinone s. AB - Reaction of 5-aryl-2-amino-1,3,4-oxadiazoles (BI-VI), obtained by the oxydative cyclization of aromatic aldehyde semicarbazones (AI-VI), with alpha-chloro-alpha phenylacetyl chloride and alpha-bromopropionyl bromide yielded 5-aryl-2-[(alpha chloro-alpha-phenylacetyl)amino]-1,3,4-oxadiazoles (Ia-VIa) and 5-aryl-2-[(alpha bromopropionyl)amino]-1,3,4-oxadiazoles (VIIa-XIIa), respectively. Furthermore, Ia-XIIa were refluxed with ammonium thiocyanate to give 5-phenyl/methyl-2-[(5 aryl-1,3,4-oxadiazol-2-yl)imino]-4-thiazo lidinones (It-XIIt). All compounds were tested for antibacterial activity against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. They were all found to possess significant activity against S. aureus with MIC values ranging from 0.24 to 125 micrograms/ml. LD50 of compounds chosen as prototypes are estimated. PMID- 9368709 TI - Influence of formulation on the in vitro transdermal penetration of flutrimazole. AB - Flutrimazole (1-[(2-fluorophenyl)(4-fluorophenyl)phenylmethyl]-1 H-imidazole, CAS 119006-77-8, UR-4056) is a new wide spectrum local imidazolic antifungal agent that has already been formulated as a dermal cream (FDC). A comparative study was carried out of the release of flutrimazole from two emulsions in which the drug has been incorporated differently: one dissolved in the oily phase (E24) and the other dispersed in the aqueous formulation phase (E25). Based on the E25 formulation, two more dermal creams were prepared, E27 with benzyl alcohol and E28 with diazolidinyl urea as preservative agents. A comparative study of transdermal penetration including E27, E28, FDC (reference 1% flutrimazole dermal cream) and 1% flutrimazole hydroalcoholic solution was also performed. An amount of the sample dosage form containing 10 mg of flutrimazole was applied to a Franz type cell. The penetration membrane used was cellulose acetate in the release studies and human skin provided by a plastic surgery clinic in the transdermal penetration study. The amount released after 7 h was 36.3 +/- 4.9 micrograms when flutrimazole was dissolved (E24) and 35.9 +/- 5.3 micrograms when flutrimazole was dispersed (E25). Although the differences were not significant, the cream with dispersed flutrimazole was selected for further penetration studies due to its better stability observed in previous studies. The amounts of drug penetrated after 44 h were 31.3, 41.5, 38.3 and 186.5 micrograms for E27, E28, FDC dermal creams and topical hydroalcoholic solution, respectively. The solution showed a statistically significant difference (p < 0.05) from the other formulations, however, no differences were observed between the dermal cream formulations. No differences were neither obtained between the different dermal creams when the amount of drug retained in the skin was compared. This allows to assert that the excipients used do not have different influences on transdermal penetration. In all cases, the mean quantity penetrated in relation to the dose applied was at most 0.5%. These results allow to infer that flutrimazole shows scarce transdermal penetration. Further, the amount of flutrimazole retained per gram of skin is more than 100 times the MIC per gram obtained in previous in vitro studies. It may be assumed that the topical application of the new formulations assayed would allow to obtain a good therapeutic response. PMID- 9368710 TI - Effects of mistletoe lectin I on human blood cell lines and peripheral blood cells. Cytotoxicity, apoptosis and induction of cytokines. AB - The effects of mistletoe lectin I (ML I) on the human T-cell leukemia line MOLT 4, the monocytic line THP-1 and on human peripheral blood mononuclear cells (PBMC) were investigated with regard to general cell viability and induction of apoptosis. Using a sensitive serum-free cytotoxicity assay, the time- and concentration-dependent direct toxicity towards MOLT-4 cells was determined with IC50-values ranging from 20-40 pg/ml (300-600 fmol/l). Investigations on the time course of the toxic effect using selected concentrations of ML I revealed distinct response curves for concentrations of high, low and intermediate toxicity, respectively. The ratio of apoptotic to viable MOLT-4 cells was determined after treatment with ML I for 24 h. Apoptosis and cytotoxicity were correlated at low and intermediate concentrations, whereas at long intervals and high concentrations of ML I mostly necrotic effects were observed. The data showed that in the concentration range of low cytotoxicity ML I-induced cell death is quantitatively due to apoptotic processes. The immunomodulatory activity of ML I was investigated in vitro by measuring cytokine release. At concentrations of low cytotoxicity ML I showed immunostimulatory activity on PBMC and THP-1. RT-PCR with THP-1 cells confirmed that cytokine induction by ML I is regulated on the transcriptional level. These findings suggest that in the blood cells investigated both apoptosis and cellular signalling are induced by the same concentration range of ML I. PMID- 9368713 TI - Spontaneous polyploidization results in apoptosis in a Meth-A tumor cell line. AB - Cultured Meth-A cells always include a small fraction of large cells, which had a DNA content above 4c (polyploid cells). The process from the formation to the disintegration of polyploid Meth-A cells was measured by means of time-lapse videography. Polyploid Meth-A cells arose spontaneously from normal cells (polyploidization), then died by apoptosis. The fraction of polyploid cells gradually increased in seven day-exponential cultures with a low concentration of demecolcine, which is a specific inhibitor of cell division. The results revealed that the polyploid Meth-A cells are generated from normal cells by failing cell division and that they die by apoptosis. PMID- 9368711 TI - Effect of histamine on human fibroblast in vitro. AB - The effects of histamine (CAS 51-45-6) on cell growth, collagen synthesis of fibroblasts derived from human foreskin, and on fibroblast-mediated collagen remodelling were studied. The cellmat DNA content was measured 2 days after human fibroblasts were plated at a split ratio of 1:10. Effect of histamine (10(-9)-10( 4) mol/l) on the increase of DNA content was not observed. Fibroblasts at confluence were cultured with histamine only, and with pyrilamine or cimetidine in addition to histamine for 2 h. Type I procollagen C-peptide in the medium was measured by enzyme immunoassay and was corrected by DNA content. Type I collagen synthesis was stimulated by histamine (10(-6)-10(-4) mol/l) and its stimulation was inhibited by cimetidine, but not by pyrilamine. Collagen solution containing fibroblast was incubated until gelation. It was incubated with histamine only, and with pyrilamine or cimetidine in addition to histamine. The gel contraction was stimulated by histamine (10(-4) mol/l) and its stimulation was inhibited by pyrilamine, but not by cimetidine. These facts suggests that histamine stimulates type I collagen synthesis of fibroblast and collagen remodeling via H2 and H1 receptors, respectively. PMID- 9368712 TI - Regulation of intracellular pH in sea urchin eggs by medium containing both weak acid and base. AB - To establish a method of pHi regulation and to understand the pH regulation mechanism in the cell, we investigated the pHi response of unfertilized or fertilized eggs of sea urchin, applying sea water containing both weak permeant acid, acetic acid and/or base, ammonia, to eggs. Pyranine was employed as a pH indicator to measure intracellular pH (pHi) by microfluorometry. The unfertilized/fertilized eggs had a pHi of 6.80/7.34 and 6.81/7.32 for Schaphechinus mirabilis and Hemicentrotus pulcherrimus, respectively. With the addition of both acetic acid and ammonia to the media, pHi changed linearly against extracellular pH (pHo) between 6-8 and was almost equal to pHo at the concentration of 20 mM acetate and ammonia. This mixed application was proved to be available for regulating pHi at the desired value within a wide range involving the original pHi by a single solution system. pHi after the treatment was dependent on various factors, such as the concentration of the weak acid and base, the pHi before the treatment, and pH buffering power in the cytoplasm. The latter was estimated to be 43 mM and 58 mM in unfertilized and fertilized eggs, respectively, from the measurement of pHi change induced by microinjecting a HEPES solution, assuming that the pH buffering power is caused by phosphate. PMID- 9368715 TI - Binding of lectins to novel migration promoters on cardiac mesenchymal cells in the chick. AB - Chicken serum promotes migration of cardiac mesenchymal cells of chick embryos in vitro. In the present study, migration promotion of unknown migration promoters in chicken serum was examined by using lectins. Cardiac mesenchymal cells of the conotruncal and atrioventricular cushions were cultured on collagen type-I gel with medium including chicken serum. A concentration (100 micrograms/ml) of Concanavalin A (Con A), peanut agglutinin (PNA), pisum sativum agglutinin (PSA), soybean agglutinin (SBA) or wheat germ agglutinin (WGA) was added to the medium. Con A, PSA, and WGA inhibited migration, while PNA and SBA did not affect migration of cardiac mesenchymal cells. WGA inhibited migration in a concentration dependent manner. Preincubation of WGA with specific binding monosaccharides (alpha-D-N-acetylglucosamine and alpha-D-N-acetylneuraminic acid) clearly reduced the inhibition ability of WGA, while preincubation of Con A and PSA with alpha-D-mannose and alpha-D-glucose did not. On the other hand, Con A binding proteins, eluted from a Con A affinity column with the buffer including alpha-D-mannose and alpha-D-glucose, promoted migration of cardiac mesenchymal cells, as did WGA-binding proteins. These proteins promoted migration in a concentration dependent manner. Western blotting showed that PSA bound the subunits of collagen type-I, but ConA and WGA did not. In migration inhibition assays by monosaccharides, only N-acetylneuraminic acid inhibited migration of cardiac mesenchymal cells. These results suggested that chicken serum contains novel migration promoters for chick cardiac mesenchymal cells. The promoters are proposed to have the terminal N-acetylglucosamine, N-acetylneuraminic acid, and glucose and/or mannose residues. PMID- 9368714 TI - Strain specific production of a negative regulator of IL-3 (NIL-3): difference in the negative feedback mechanism of hemopoiesis among mouse strains. AB - The producing cells of the negative regulator of interleukin-3 (NIL-3) were investigated. The 5-fluorouracil-treated bone marrow cells did not produce NIL-3. The bone marrow cells of stem cell-depleted W/WV mouse did not produce the NIL-3, either. The production of NIL-3 was different among mouse strains. Mice of C3H/HeN, A/J and ICR strains produced NIL-3, but the C57BL/6 mice did not produce NIL-3. These results indicate that the negative feedback mechanism of hemopoiesis is different among mouse strains. In the present study, we could not definitely identify the NIL-3 producing cells, although the present results are suggestive that the stem cells in cycle are a NIL-3 producer. Instead, we found that hemopoietic regulatory mechanisms might be different among mouse strains, especially in C57BL/6 mice. PMID- 9368716 TI - Inhibition of mitochondrial protein synthesis impaired C2C12 myoblast differentiation. AB - Various factors are required for the regulation of muscle cell differentiation. In an attempt to elucidate the mechanism underlying myogenesis, we examined the possible contribution of mitochondria to terminal differentiation of murine myoblast cell line, C2C12, using a specific inhibitor for mitochondrial protein synthesis, tetracycline. Tetracycline impaired myotube formation and induction of muscle creatine kinase activity which was specifically observed in differentiated myocytes. Transcript levels of muscle-specific proteins, creatine kinase and troponin-I were also significantly suppressed in a dose-dependent manner. However, those proteins with myogenic regulatory factors, MyoD and myogenin, and common proteins including glycolytic enzymes were not affected. Cellular viability, mitochondrial transcription, and mitochondrial proliferation were confirmed not to be impaired by tetracycline treatment. These results suggest that mitochondrial stress may affect regulation of differentiation-specific gene expression. This system may contribute to an understanding of mechanisms for differentiation inhibition caused by inhibitors of mitochondrial protein synthesis that have also been observed in other kinds of cells. PMID- 9368719 TI - The inhibition of motility of demembranated spermatozoa by anti-tubulin antibodies. AB - The effects of monoclonal anti-tubulin antibodies on the motility of demembranated and reactivated sea urchin spermatozoa were investigated. Two out of ten antibodies examined significantly reduced the motility of spermatozoa, both in motile rate and swimming speed. The binding patterns of the two antibodies YL1/2 and TUB2.1 to the axoneme were studied by immunoblot, immunofluorescence, and immuno-electron microscopy. YL1/2 bound to the axoneme in a specific pattern; signals were very intense in the tail, rich in the proximal portion, and scarce in the middle part of the axoneme. Because the inhibitory effects of the antibody on the motility of spermatozoa with fully long flagella and short flagella were similar, the inhibition was probably due to the binding of the antibody to the proximal portion of the flagellum. TUB2.1 evenly bound to the axoneme by immunofluorescence and immunoelectron microscopy. On the other hand, the eight antibodies which did not affect sperm motility, did not bind to unfixed axonemes, although epitopes for these antibodies were detected abundantly in the axoneme. PMID- 9368717 TI - Nuclear concentration of gold labeled-testosterone-bovine serum albumin conjugate injected intravenously in the hormone-target cells of rat. AB - We examined whether testosterone-bovine serum albumin conjugate (testosterone BSA) showed similar distribution to radiolabeled testosterone in vivo, by injecting 2-nm colloidal gold labeled-testosterone-BSA (testosterone-BSA-gold) from rat tail vein. The testosterone-BSA-gold with the silver enhancement became visible as silver deposits under electron microscope in nuclei of Leydig cells, Sertoli cells, spermatogonia, spermatocytes and spermatids in the testis, those of the epithelial cells in the seminal vesicle and of the cardiac muscle cells in the heart of rat killed 2 h after the injection. Few deposits were present on the non-target cell nuclei in thymus and spleen. In the liver cells, the deposits were observed in the cytoplasm, but few in the nucleus. At high-power magnification without silver enhancement, the gold particles were found in the target cell nuclei in the testis. In control rat injected with BSA labeled with 2 nm colloidal gold, the percentages of nuclei showing the deposits were fewer than those in the rat injected testosterone-BSA-gold in the target cells. The deposits were also few in the nuclei of non-target cells in control rat. These results suggest that testosterone-BSA-gold is useful for morphological study of testosterone target cells, and imply that BSA conjugated with testosterone can enter the target cell nuclei of the rat. PMID- 9368718 TI - Reconstruction culture system simulating human synovium: a three-dimensional collagen gel culture of synoviocytes. AB - We developed a reconstruction culture system simulating human synovium to investigate the synoviocytes in a more physiological condition. This system with two types of dishes provided the two separated spaces corresponding to the joint cavity and nutrient vessels. The isolated normal synoviocytes were cultured in type-I collagen gel with a layer-seeded on top in a smaller inner dish with a porous bottom, which was placed in a larger outer dish. We added hyaluronic acid solution to the space on the gel to make an environment close to the physiological joint cavity. The space between the inner and outer dishes was filled with a complete medium to nourish the synoviocytes through the porous filter (Experiment 1). In addition, to examine cell-to-cell interaction, we created a co-culture model by mixing synoviocytes and peripheral blood mononuclear cells in the collagen gel matrix (Experiment 2). In this way we could reconstruct the synovium in vitro. The synoviocytes could survive and maintain their characteristics for four weeks of culture. In Experiment 1, almost all the cells were similar to type B synovial cells by histological, immunohistochemical and electron microscopic observations. In Experiment 2, the spherical cells in abundance of lysosomes like type A synovial cells appeared sporadically in the lining layer. Immunohistochemically, the majority of cultured cells expressed CD68 and matrix metalloproteinase 3. This culture system promises to be of use in investigating the pathogenesis of various joint diseases. PMID- 9368720 TI - An altered nuclear migration into the daughter bud is induced by the cyclin A1 mediated Cdc28 kinase through an aberrant spindle movement in Saccharomyces cerevisiae. AB - A strain of Saccharomyces cerevisiae that contains an integrated copy of a Xenopus cyclin A1 gene under the control of the GAL1 promoter has been constructed. On inducing expression of cyclin A1, the nuclear migration that occurs prior to division becomes aberrant. Instead of migrating to the neck between the mother cell and daughter bud, the nucleus, the short mitotic spindle and its associated two spindle pole bodies entered the daughter bud. This phenotype was induced by expression of an indestructible cyclin mutant, but not by a mutated cyclin A1 unable to activate Cdc28 kinase. The nuclear abnormality induced by cyclin A1 was overcome by cdc28 mutations that abolish its ability to bind cyclin A1. Both yeast cyclin Clb3 and Xenopus mitotic cyclin B produced the same phenotype, whereas G1 cyclin Cln2 did not. The results suggest that the proper movement of the nucleus through the spindle function during mitosis requires the appropriate activity of Cdc28 kinase mediated by specific cyclins. PMID- 9368721 TI - A novel truncated variant form of Ebk/MDK1 receptor tyrosine kinase is expressed in embryonic mouse brain. AB - We have isolated cDNA clones from a mouse embryonic head cDNA library that encode one member of the Eph/Eck family of receptor tyrosine kinases (RTKs), Ebk/MDK1. Among the 10 clones, two showed full-length type comprising extracellular, transmembrane and intracellular kinase domains. Two of them were modified just after the transmembrane domain and stop codon appeared before completing the kinase domain. This truncated form also had a deletion of five amino acids at the extracellular domain, indicating that it is a novel variant of Ebk/MDK1. RNase protection assay showed that this truncated deleted type, named Ebk-td1, is present in the head of embryos, although the amount is less compared to that of the full-length type having a deletion of four amino acids. Considering the source and expression of Ebk/MDK1 mRNAs, they may have an important role, accompanied with a possible regulatory role of the truncated variant, during neural development and/or in embryogenesis. PMID- 9368723 TI - Nitric oxide in tumour biology and cancer therapy. Part 1: Physiological aspects. PMID- 9368722 TI - Extension of long cellular processes of hepatic stellate cells cultured on extracellular type I collagen gel by microtubule assembly: observation utilizing time-lapse video-microscopy. AB - Hepatic stellate cells cultured on or in freshly prepared type I collagen gel as a substratum were induced to elongate long cellular processes. The extension of the cellular processes was monitored by using video-enhanced optical microscopy. The cellular processes seemed to extend along the extracellular type I collagen fibers. Once extended cellular processes after overnight culture on type I collagen gel were retracted by cytoskeleton degradation with colchicine or cytochalasin B. The cellular processes were also retracted by treatment with protein kinase inhibitor, herbimycin A or staurosporin, or with phosphatidylinositol 3-kinase inhibitor, wortmannin. The effects of colchicine, herbimycin A, staurosporin, or wortmannin were drastic, and the cells were finally changed to a round shape within a few hours, as seen also after cold treatment at 4 degrees C. Cytochalasin B also time-dependently retracted the extended cellular processes. These results indicated that the cultured stellate cells were induced to elongate cellular processes by cell surface binding to type I collagen fibrils, followed by protein or phosphatidylinositol phosphorylation and finally F-actin and microtubule assembly. Extended long cellular processes seem to reflect the in vivo structure of hepatic stellate cells, and molecular mechanism for the extension and maintenance of cellular processes was proposed. PMID- 9368724 TI - Bleeding, clotting and cancer. PMID- 9368725 TI - Fractionation experiments in head and neck cancer: the lessons so far. PMID- 9368726 TI - Controlled trials of synchronous chemotherapy with radiotherapy in head and neck cancer: overview of radiation morbidity. AB - Recently published overviews of randomized controlled trials of simultaneous chemotherapy with radiotherapy in squamous cell carcinoma of the head and neck have demonstrated a significant survival advantage from the combined treatment compared with radiotherapy alone. However, they also showed that chemotherapy increased acute radiation morbidity, but there was no information on late effects. The 19 publications of trials of simultaneous chemotherapy contained in the overview by Munro were reviewed for morbidity data. It was found that chemotherapy significantly enhanced both acute and late effects, suggesting that the drugs may be merely dose-modifying. Future trials should be designed to determine whether or not chemotherapy improves the therapeutic ratio. PMID- 9368727 TI - Costs of conventional radical radiotherapy versus continuous hyperfractionated accelerated radiotherapy (CHART) in the treatment of patients with head and neck cancer or carcinoma of the bronchus. Medical Research Council CHART Steering Committee. AB - The objective of this study was to compare the costs of treatment with continuous hyperfractionated accelerated radiotherapy (CHART) and those of conventional radiotherapy for patients with (1) head and neck cancer and (2) carcinoma of the bronchus. The study was conducted concurrently with two multicentre randomized controlled trials. Data were collected on the use of hospital and community service resources and patients' travel for treatment. Data on resource use up to 3 months after entry to the study were available for 526 head and neck patients (314 receiving CHART and 212 conventional therapy) and 284 bronchus patients (175 CHART and 109 conventional therapy). For patients with head and neck cancer, CHART cost Pounds 1092 (P < 0.001; 95% CI 763-1421) more than conventional therapy. For patients with carcinoma of the bronchus, CHART was also more costly, with a cost differential of Pounds 698 (P < 0.001; 95% CI 392-1003). The magnitude of the cost differentials could be reduced if the working hours of radiotherapy departments were rearranged and all hospitals had access to hostel facilities. The results of this cost analysis will help to facilitate a decision about whether the benefits of CHART, as determined by the clinical trials, are worth the additional costs of hospital-based resource use. The collection of detailed patient-specific resource-use data from a number of centres allows the determination of ways for reducing the cost differential between therapies and making CHART a more cost effective treatment alternative. PMID- 9368728 TI - The occult head and neck primary: to treat or not to treat? AB - In patients with cervical node metastases from an unknown primary malignancy, there is unresolved controversy regarding the utility of elective irradiation of putative pharyngeal primary sites as part of the management plan. We analysed the experience of the Peter MacCallum Cancer Institute to assess the risk of withholding mucosal irradiation in relation to the diagnostic algorithm used to exclude a primary lesion at the time of initial presentation. Between 1983 and 1992, 69 patients were seen with metastatic squamous or undifferentiated carcinoma in cervical nodes from an unknown primary site. Neck nodal stage was NX or N1 13%; N2 52%; N3 35%. Nodal disease was bilateral in 12% of patients. Investigations included examination under anaesthesia, with or without random biopsies, in 84%, and CT scanning of the head and neck in 55%. Treatment was by surgery alone in four patients, by radiotherapy alone in 23, and by combined modalities in 40. Two patients received no treatment. Seventeen were treated with palliative intent. The radiotherapy fields provided comprehensive coverage of the pharynx in only eight patients and partial coverage in five. The estimated overall 5-year survival was 36%. Eleven primary tumours were detected between 7 months and 7 years after the initial treatment, of which nine were in head and neck sites. This yielded an estimated incidence of 30% at 10 years, which is similar to the risk of the development of a second primary after the successful treatment of a known head and neck cancer. Only three patients (none of whom had a CT scan as part of their initial evaluation) manifested a primary in an unirradiated pharyngeal site within 2 years of treatment. As the accuracy of imaging improves, the risk of missing an occult primary lesion will decrease further. We conclude that the use of standardized diagnostic investigations incorporating modern imaging substantially eliminates the indication for comprehensive elective mucosal irradiation with its consequent morbidity. The overriding priority in patients who present with advanced neck disease is to secure regional control. PMID- 9368729 TI - The potential for increased sparing of normal tissue in parallel opposed techniques with a multileaf collimator. AB - A multileaf collimator (MLC) can be used in parallel opposed techniques as a direct replacement for standard-shaped beam blocks. However, improved shielding is possible if the MLC field is designed to fit a target rather than to mimic a straight-edged block. This study has compared the treatment areas produced by the MLC and by conventionally blocked fields with the target area for 43 parallel opposed treatments. It was found in every case that the MLC treated less than 10% excess tissue, and, in over 70% of patients, the excess was less than 5%. The conventional fields, however, treated more than 10% excess tissue in 70% of patients. The effect of MLC orientation and the benefits of using an MLC are discussed. PMID- 9368730 TI - The reproductive imperative: a case report highlighting the possibility of using chemotherapy to conserve the testis in patients with testis cancer. AB - This report examines the dilemma that a patient, who was a doctor, faced on discovering that he was developing a second primary testicular tumour (seminoma) in a solitary testis. The usual treatment for this is radical orchidectomy. He rejected this on the grounds that he wanted to have children, and eventually decided on the use of single-agent carboplatin chemotherapy. Seventeen months after treatment, there was no evidence of tumour on MRI or ultrasound scanning and there is some recovery of spermatogenesis. So far, 13 of 14 patients treated with chemotherapy for metastatic disease (with the primary tumour being left in situ), which has normalized following treatment, have survived for more than 5 years without evidence of tumour recurrence. This approach could be a viable option for men with tumours in a solitary testis who have not completed their families. However, a larger prospective study is essential to determine whether this approach is safe, so that these patients will not have to bear the psychological burden of choosing between their chances of survival and the possibility of fathering children. PMID- 9368731 TI - The increasing efficacy of breast cancer treatment. AB - Breast cancer is the commonest malignancy in women and although identification of this multi-system disease has increased, the survival rates have not dramatically altered over the past four decades. Optimium treatment of patients with breast cancer is a subject of great debate and traditionally may be divided into surgery, radiotherapy, chemotherapy and hormone manipulation. Halsted's radical mastectomy, although initially superseded by more mutilating surgery involving removal of tumour, breast, pectoral muscles and axillary contents, has given way to more conservative surgery and breast conservation, so now removal of the tumour with a marginal of healthy tissue is possible. Additional loco-regional radiotherapy has added to the increasing number of treatment options available to both doctor and patient. Systemic adjuvant therapy, primarily hormonal therapy, is used with the aim of decreasing the incidence of recurrence and distant tumour development. Through the process of randomized controlled trials these new therapeutic treatments have shown to be effective in the treatment of locoregional disease. Surgery in patients with advanced systemic disease is limited, however radiotherapy is of considerable importance and can be used to treat or palliate sites of metastases. In recent years trials have assessed chemotherapeutic regimens. However, limited number of patients and adequate randomization have hindered the confident acceptance of these results. Cyclophosphamide, methotrexate and 5 fluorouracil still remain the standard chemotherapeutic regimen, however many new drugs are currently undergoing trials and these or combinations of these may prove to be of future clinical use. Dramatic advances in cell and molecular biology have allowed the development of novel breast cancer therapies. Specific oncogenes and loss of tumour suppressor genes have been associated with decrease patient survival, with the presence of lymph node metastases and with decreased relapse free survival. Growth factor receptor blockers and tyrosine kinase inhibitors may be developed to specifically eradicate breast cancer cells. Immunotherapy and gene therapy may produce effective therapies. Trials utilizing cytokines and trials increasing the immunogenicity of tumours have already reported promising results. Surgery, chemotherapy, radiotherapy and hormone manipulation are the major treatment arms of breast cancer therapy. However, breast cancer still accounts for 20 percent of all female cancer deaths and the overall survival of patients has remained relatively static over the past forty years. From our increasing understanding of the pathological processes involved in the development and spread of breast cancer, new pharmaceutical, immunological and gene therapies may dramatically increase the cure rate of this serious disease. PMID- 9368732 TI - Intramedullary thoracic cord metastasis managed effectively without surgery. AB - Spinal intramedullary metastases present with rapidly progressing neurological deficits and have an extremely poor prognosis. Prompt investigation and management are required. This case history illustrates that radiotherapy and steroids can be effective in returning motor function. The behaviour of the primary tumour and the stage of the disease influence whether surgery is appropriate. PMID- 9368733 TI - Intradural drop metastases in oligodendrogliomas. AB - The case history is presented of a patient with primary intracerebral oligodendroglioma, who received multiple therapies for local recurrence. Four years following the initial diagnosis, the patient presented with spinal cord compression due to intradural metastases. The patterns of recurrence and metastases in oligodendroglioma are discussed. PMID- 9368736 TI - A conserved ancient domain joins the growing superfamily of 3'-5' exonucleases. PMID- 9368734 TI - A role for molecular radiobiology in radiotherapy? PMID- 9368737 TI - Photoactivation of green fluorescent protein. PMID- 9368738 TI - Site-specific recombination: synapsis and strand exchange revealed. AB - Recently determined crystal structures of several members of the lambda integrase family of site-specific recominases have provided insights into the cis versus trans action of active site constituents, and hte processes of synapsis and strand exchange. PMID- 9368739 TI - Cell cycle: checkpoint proteins and kinetochores. AB - Vertebrate homologs of yeast spindle assembly checkpoint proteins are localized to kinetochores and may act as a sensor for proper chromosome attachment to the mitotic spindle. PMID- 9368740 TI - Yeast prions: inheritance by seeded protein polymerization? PMID- 9368741 TI - Muscle determination: another key player in myogenesis? AB - The steps that commit multipotential somite cells to muscle differentiation are being elucidated. Recent results show that pax3 is an upstream regulator of myoD, one of the key genes in myogenic lineage determination. PMID- 9368742 TI - Natural killer cells: influence of the home environment. AB - Recent results show that the repertoire of anti-MHC class 1-specific inhibitory receptors expressed by natural killer cells is influenced by self class 1 molecules in such a way as to minimize the number of cells with multiple self reactive inhibitory receptors. PMID- 9368743 TI - Neurotrophins: new roles for a seasoned cast. AB - Recent studies suggest that endogenous neurotrophins play a central role in the patterning of cortical connections and in cortical synaptic physiology. Do these effects of neurotrophids reflect independent cellular events, or are they manifestations of a single cellular mechanism central to developmental plasticity? PMID- 9368744 TI - Molecular motors: the natural economy of kinesin. AB - Kinesin is a molecular-scale walking machine. New analyses of its mechanism indicate that each step along a microtubule consumes one ATP molecule, and that the binding and cleavage of ATP precede detachment of the molecule's 'feet'. Directional walking ensues if ATP processing occurs preferentially on one foot. PMID- 9368745 TI - Arthropod evolution: same Hox genes, different body plans. PMID- 9368746 TI - Photosynthesis: the paradox of carbon dioxide efflux. AB - The discovery that photosynthetic marine cyanobacteria can actually leak CO2 has been predicted from theory but, until now, never experimentally demonstrated. The apparent paradox can be explained by known chemistry and biochemistry, but the phenomenon may have important implications for paleoclimatology. PMID- 9368747 TI - T-cell signaling: the importance of receptor clustering. AB - T-cell receptors bound to peptide-MHC molecules undergo higher-order oligomerization in solution. This observation, the low-affinity-recognition properties of T-cell receptors, and other indications that such receptors undergo rapid, serial engagement by a single ligand suggest a dynamic clustering model of T-cell signaling. PMID- 9368748 TI - Stereopsis: how the brain sees depth. AB - Recent studies show how single neurons detect binocular disparities. But how these signals are used for stereoscopic perception remains a puzzle. PMID- 9368749 TI - Cytokinesis: a regulatory role for Ras-related proteins? PMID- 9368750 TI - Plant development: timing when to flower. AB - The time to flowering in Arabidopsis is controlled by many genes; recently, progress has been made in the cloning of a number of such genes. One of them, the FCA gene, turns out to encode an RNA binding protein. PMID- 9368751 TI - Chromatin: the nucleosome unwrapped. AB - The structure of the nucleosome core particle has been determined by X-ray crystallography at 2.8 A resolution. The structure has several significant surprises, and provides important new insights into the structure and function of chromatin. PMID- 9368752 TI - Genome sequences: genome sequence of a model prokaryote. AB - The complete Escherichia coli genome sequence is now known; it should greatly facilitate the analysis of other genomes, but a lot remains to be learnt about E. coli itself. About half the genes were previously uncharacterized, but expanding databases and improving analysis methods will help predict their functions. PMID- 9368753 TI - Phantom motion after effects--evidence of detectors for the analysis of optic flow. AB - BACKGROUND: Electrophysiological recording from the extrastriate cortex of non human primates has revealed neurons that have large receptive fields and are sensitive to various components of object or self movement, such as translations, rotations and expansion/contractions. If these mechanisms exist in human vision, they might be susceptible to adaptation that generates motion aftereffects (MAEs). Indeed, it might be possible to adapt the mechanism in one part of the visual field and reveal what we term a 'phantom MAE' in another part. RESULTS: The existence of phantom MAEs was probed by adapting to a pattern that contained motion in only two non-adjacent 'quarter' segments and then testing using patterns that had elements in only the other two segments. We also tested for the more conventional 'concrete' MAE by testing in the same two segments that had adapted. The strength of each MAE was quantified by measuring the percentage of dots that had to be moved in the opposite direction to the MAE in order to nullify it. Four experiments tested rotational motion, expansion/contraction motion, translational motion and a 'rotation' that consisted simply of the two segments that contained only translational motions of opposing direction. Compared to a baseline measurement where no adaptation took place, all subjects in all experiments exhibited both concrete and phantom MAEs, with the size of the latter approximately half that of the former. CONCLUSIONS: Adaptation to two segments that contained upward and downward motion induced the perception of leftward and rightward motion in another part of the visual field. This strongly suggests there are mechanisms in human vision that are sensitive to complex motions such as rotations. PMID- 9368754 TI - Sustained net CO2 evolution during photosynthesis by marine microorganisms. AB - BACKGROUND: Many aquatic photosynthetic microorganisms possess an inorganic carbon-concentrating mechanism that raises the CO2 concentration at the intracellular carboxylation sites, thus compensating for the relatively low affinity of the carboxylating enzyme for its substrate. In cyanobacteria, the concentrating mechanism involves the energy-dependent influx of inorganic carbon, the accumulation of this carbon--largely in the form of HCO3(-)-in the cytoplasm, and the generation of CO2 at carbonic anhydrase sites in close proximity to the carboxylation sites. RESULTS: During measurements of inorganic carbon fluxes associated with the inorganic-carbon-concentrating mechanism, we observed the surprising fact that several marine photosynthetic microorganisms, including significant contributors to oceanic primary productivity, can serve as a source of CO2 rather than a sink during CO2 fixation. The phycoerythrin-possessing cyanobacterium Synechococcus sp. WH7803 evolved CO2 at a rate that increased with light intensity and attained a value approximately five-fold that for photosynthesis. The external CO2 concentration reached was significantly higher than that predicted for chemical equilibrium between HCO3- and CO2, as confirmed by the rapid decline in the CO2 concentration upon the addition of carbonic anhydrase. Measurements of oxygen exchange between water and CO2, by means of stable isotopes, demonstrated that the evolved CO2 originated from HCO3- taken up and converted intracellularly to CO2 in a light-dependent process. CONCLUSIONS: We report net, sustained CO2 evolution during photosynthesis. The results have implications for energy balance and pH regulation of the cells, for carbon cycling between the cells and the marine environment, and for the observed fractionation of stable carbon isotopes. PMID- 9368755 TI - Cryo-electron microscopy reveals ordered domains in the immature HIV-1 particle. AB - BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) is the causative agent of AIDS and the subject of intense study. The immature HIV-1 particle is traditionally described as having a well ordered, icosahedral structure made up of uncleaved Gag protein surrounded by a lipid bilayer containing envelope proteins. Expression of the Gag protein in eukaryotic cells leads to the budding of membranous virus-like particles (VLPs). RESULTS: We have used cryo-electron microscopy of VLPs from insect cells and lightly fixed, immature HIV-1 particles from human lymphocytes to determine their organization. Both types of particle were heterogeneous in size, varying in diameter from 1200-2600 A. Larger particles appeared to be broken into semi-spherical sectors, each having a radius of curvature of approximately 750 A. No evidence of icosahedral symmetry was found, but local order was evidenced by small arrays of Gag protein that formed facets within the curved sectors. A consistent 270 A radial density was seen, which included a 70 A wide low density feature corresponding to the carboxy terminal portion of the membrane attached matrix protein and the amino-terminal portion of the capsid protein. CONCLUSIONS: Immature HIV-1 particles and VLPs both have a multi-sector structure characterized, not by an icosahedral organization, but by local order in which the structures of the matrix and capsid regions of Gag change upon cleavage. We propose a model in which lateral interactions between Gag protein molecules yields arrays that are organized into sectors for budding by RNA. PMID- 9368756 TI - The solution structure of the amino-terminal HHCC domain of HIV-2 integrase: a three-helix bundle stabilized by zinc. AB - BACKGROUND: Integrase mediates a crucial step in the life cycle of the human immunodeficiency virus (HIV). The enzyme cleaves the viral DNA ends in a sequence dependent manner and couples the newly generated hydroxyl groups to phosphates in the target DNA. Three domains have been identified in HIV integrase: an amino terminal domain, a central catalytic core and a carboxy-terminal DNA-binding domain. The amino-terminal region is the only domain with unknown structure thus far. This domain, which is known to bind zinc, contains a HHCC motif that is conserved in retroviral integrases. Although the exact function of this domain is unknown, it is required for cleavage and integration. RESULTS: The three dimensional structure of the amino-terminal domain of HIV-2 integrase has been determined using two-dimensional and three-dimensional nuclear magnetic resonance data. We obtained 20 final structures, calculated using 693 nuclear Overhauser effects, which display a backbone root-mean square deviation versus the average of 0.25 A for the well defined region. The structure consists of three alpha helices and a helical turn. The zinc is coordinated with His 12 via the N epsilon 2 atom, with His16 via the N delta 1 atom and with the sulfur atoms of Cys40 and Cys43. The alpha helices form a three-helix bundle that is stabilized by this zinc-binding unit. The helical arrangement is similar to that found in the DNA binding domains of the trp repressor, the prd paired domain and Tc3A transposase. CONCLUSION: The amino-terminal domain of HIV-2 integrase has a remarkable hybrid structure combining features of a three-helix bundle fold with a zinc-binding HHCC motif. This structure shows no similarity with any of the known zinc-finger structures. The strictly conserved residues of the HHCC motif of retroviral integrases are involved in metal coordination, whereas many other well conserved hydrophobic residues are part of the protein core. PMID- 9368757 TI - p53 activity is essential for normal development in Xenopus. AB - BACKGROUND: The tumor suppressor p53 plays a key role in regulating the cell cycle and apoptosis in differentiated cells. Mutant mice lacking functional p53 develop normally but die from multiple neoplasms shortly after birth. There have been hints that p53 is involved in morphogenesis, but given the relatively normal development of p53 null mice, the significance of these data has been difficult to evaluate. To examine the role of p53 in vertebrate development, we have determined the results of blocking its activity in embryos of the frog Xenopus laevis. RESULTS: Two different methods have been used to block p53 protein activity in developing Xenopus embryos--ectopic expression of dominant-negative forms of human p53 and ectopic expression of the p53 negative regulator, Xenopus dm-2. In both instances, inhibition of p53 activity blocked the ability of Xenopus early blastomeres to undergo differentiation and resulted in the formation of large cellular masses reminiscent of tumors. The ability of mutant p53 to induce such developmental tumors was suppressed by co-injection with wild type human or wild-type Xenopus p53. Cells expressing mutant p53 activated zygotic gene expression and underwent the mid-blastula transition normally. Such cells continued to divide at approximately normal rates but did not form normal embryonic tissues and never underwent terminal differentiation, remaining as large, yolk-filled cell masses that were often associated with the neural tube or epidermis. CONCLUSIONS: In Xenopus, the maternal stockpile of p53 mRNA and protein seems to be essential for normal development. Inhibiting p53 function results in an early block to differentiation. Although it is possible that mutant human p53 proteins have a dominant gain-of-function or neomorphic activity in Xenopus, and that this is responsible for the development of tumors, most of the evidence indicates that this is not the case. Whatever the basis of the block to differentiation, these results indicate that Xenopus embryos are a sensitive system in which to explore the role of p53 in normal development and in developmental tumors. PMID- 9368758 TI - Long-term monitoring of circadian rhythms in c-fos gene expression from suprachiasmatic nucleus cultures. AB - BACKGROUND: The AP-1 family of transcription factors has been implicated in the control of the expression of many genes in response to environmental signals. Previous studies have provided temporal profiles for c-fos expression by taking measurements from many animals at several points in time, but these studies provide limited information about dynamic changes in expression. Here, we have devised a method of continuously measuring c-fos expression. RESULTS: A transgenic mouse line expressing the human c-fos promoter linked to the firefly luciferase reporter gene (fos/luc) was generated to continuously monitor c-fos gene expression. A second transgenic mouse line expressing luciferase under the control of the cytomegalovirus promoter (CMV/luc) served as a control. Luminescence originating from identifiable brain regions was imaged from fos/luc brain slice cultures. Expression of the fos/luc transgene accurately reflected transcriptional responses of the endogenous c-fos gene. Dynamic changes in fos/luc expression in suprachiasmatic nuclei (SCN) explant cultures were monitored continuously, and luminescence showed almost 24 hour rhythms lasting up to five circadian cycles. In contrast, bioluminescence monitored from CMV/luc SCN explant cultures was not rhythmic. CONCLUSION: The fos/luc transgenic mouse will be useful for long-term, non-invasive monitoring of c-fos transcriptional responses to the changing cellular environment. Circadian rhythms in c-fos expression can be monitored non-invasively in real time from the SCN, clearly demonstrating that c-fos transcription is regulated by the circadian clock. PMID- 9368759 TI - The importin-beta family member Crm1p bridges the interaction between Rev and the nuclear pore complex during nuclear export. AB - BACKGROUND: The human immunodeficiency virus (HIV-1) uses the viral protein Rev to regulate gene expression by promoting the export of unspliced and partially spliced viral transcripts. Rev has been shown to function in a variety of organisms, including Saccharomyces cerevisiae. The export activity of Rev depends on a nuclear export signal (NES), which is believed to interact either directly or indirectly with the nuclear pore complex to carry out its export function. Crm1p is a member of the importin-beta protein family, other members of which are known to be directly involved in nuclear import. Crm1p has recently been shown to contribute to nuclear export in vertebrate systems. Here, we have studied this mechanism of nuclear to cytoplasmic transport. RESULTS: Viable mis-sense mutations in the CRM1 gene substantially reduced or eliminated the biological activity of Rev in S. cerevisiae, providing strong evidence that Crm1p also contributes to transport of Rev NES-containing proteins and ribonucleoproteins in this organism. Crm1p interacted with FG-repeat-containing nuclear pore proteins as well as Rev, and we have demonstrated that the previously described two-hybrid interaction between Rev and the yeast nuclear pore protein Rip1p is dependent on wild-type Crm1p. CONCLUSIONS: We conclude that Crm1p interacts with the Rev NES and nuclear pore proteins during delivery of cargo to the nuclear pore complex. Our findings also agree well with current experiments on Crm1p orthologs in Schizosaccharomyces pombe and in vertebrate systems. PMID- 9368760 TI - 3-Phosphoinositide-dependent protein kinase-1 (PDK1): structural and functional homology with the Drosophila DSTPK61 kinase. AB - BACKGROUND: The activation of protein kinase B (PKB, also known as c-Akt) is stimulated by insulin or growth factors and results from its phosphorylation at Thr308 and Ser473. We recently identified a protein kinase, termed PDK1, that phosphorylates PKB at Thr308 only in the presence of lipid vesicles containing phosphatidylinositol 3,4,5-trisphosphate (Ptdlns(3,4,5)P3) or phosphatidylinositol 3,4-bisphosphate (Ptdlns(3,4)P2). RESULTS: We have cloned and sequenced human PDK1. The 556-residue monomeric enzyme comprises a catalytic domain that is most similar to the PKA, PKB and PKC subfamily of protein kinases and a carboxy-terminal pleckstrin homology (PH) domain. The PDK1 gene is located on human chromosome 16p13.3 and is expressed ubiquitously in human tissues. Human PDK1 is homologous to the Drosophila protein kinase DSTPK61, which has been implicated in the regulation of sex differentiation, oogenesis and spermatogenesis. Expressed PDK1 and DSTPK61 phosphorylated Thr308 of PKB alpha only in the presence of Ptdlns(3,4,5)P3 or Ptdlns(3,4)P2. Overexpression of PDK1 in 293 cells activated PKB alpha and potentiated the IGF1-induced phosphorylation of PKB alpha at Thr308. Experiments in which the PH domains of either PDK1 or PKB alpha were deleted indicated that the binding of Ptdlns(3,4,5)P3 or Ptdlns(3,4)P2 to PKB alpha is required for phosphorylation and activation by PDK1. IGF1 stimulation of 293 cells did not affect the activity or phosphorylation of PDK1. CONCLUSIONS: PDK1 is likely to mediate the activation of PKB by insulin or growth factors. DSTPK61 is a Drosophila homologue of PDK1. The effect of Ptdlns(3,4,5)P3/Ptdlns(3,4)P2 in the activation of PKB alpha is at least partly substrate directed. PMID- 9368762 TI - A novel Cdc42Hs mutant induces cellular transformation. AB - Cdc42Hs is a small GTPase of the Rho-subfamily, which regulates signaling pathways that influence cell morphology and polarity, cell-cycle progression and transcription. An essential role for Cdc42Hs in cell growth regulation has been suggested by the finding that the Dbl oncoprotein is an upstream activator-a guanine nucleotide exchange factor (GEF)-for Cdc42Hs, and that activated mutants of the closely related GTPases Rac and Rho are transforming. As we were unable to obtain significant over-expression of GTPase-defective Cdc42Hs mutants, we have generated a mutant, Cdc42Hs(F28L), which can undergo spontaneous GTP-GDP exchange while maintaining full GTPase activity, and thus should exhibit functional activities normally imparted by Dbl. In cultured fibroblasts, Cdc42Hs(F28L) activated the c-Jun kinase (JNK1) and stimulated filopodia formation. Cells stably expressing Cdc42Hs(F28L) also exhibited several hallmarks of transformation-reduced contact inhibition, lower dependence on serum for growth, and anchorage-independent growth. Our findings indicate that Cdc42Hs plays a role in cell proliferation, and is a likely physiological mediator of Dbl-induced transformation. PMID- 9368761 TI - Enhancement of MSH2-MSH3-mediated mismatch recognition by the yeast MLH1-PMS1 complex. AB - DNA mismatch repair has a key role in maintaining genomic stability. Defects in mismatch repair cause elevated spontaneous mutation rates and increased instability of simple repetitive sequences, while mutations in human mismatch repair genes result in hereditary nonpolyposis colorectal cancers. Mismatch recognition represents the first critical step of mismatch repair. Genetic and biochemical studies in yeast and humans have indicated a requirement for MSH2 MSH3 and MSH2-MSH6 heterodimers in mismatch recognition. These complexes have, to some extent, overlapping mismatch binding specificities. MLH1 and PMS1 are the other essential components of mismatch repair, but how they function in this process is not known. We have purified the yeast MLH1-PMS1 heterodimer to near homogeneity, and examined its effect on MSH2-MSH3 binding to DNA mismatches. By itself, the MLH1-PMS1 complex shows no affinity for mismatched DNA, but it greatly enhances the mismatch binding ability of MSH2-MSH3. PMID- 9368763 TI - Bcl-2 influences axonal growth rate in embryonic sensory neurons. AB - Bcl-2 plays a key role in regulating cell survival in the immune and nervous systems. Mice lacking the bcl-2 gene have markedly reduced numbers of B and T cells as a result of increased apoptosis, whereas mice with a transgene causing high levels of Bcl-2 expression in the immune system show extended survival of B and T cells. Overexpression of Bcl-2 in cultured neurons prevents their death following neurotrophin deprivation, and mice with a bcl-2 transgene under the control of a neuron-specific enolase promoter have increased numbers of neurons in several regions. Cultured neurons expressing antisense bcl-2 RNA have an attenuated survival response to neurotrophins, and neurons of postnatal bcl-2 deficient mice die more rapidly following NGF deprivation in vitro and are present in reduced numbers in vivo. Here, we show that Bcl-2 also plays a role in regulating axonal growth rates in embryonic neurons. Sensory neurons from the trigeminal ganglia of bcl-2-deficient mouse embryos, removed from the embryo on embryonic day 11 or 12, extend axons more slowly in vitro than do neurons from wild-type embryos of the same age. Serial measurements of axonal length in the same neurons revealed that there were marked differences in axonal growth rate between bcl-2-deficient and wild-type neurons, irrespective of whether the neurons were grown with nerve growth factor, brain-derived neurotrophic factor or neurotrophin-3. Because there was no significant difference in the numbers of wild-type and bcl-2-deficient neurons surviving with each neurotrophin at this early stage of development, the effect of Bcl-2 on axonal growth rate is not a consequence of its well documented role in preventing apoptosis. PMID- 9368764 TI - Sonic hedgehog directs specialised mesoderm differentiation in the intestine and pancreas. AB - The generation of the pancreas and small intestine from the embryonic gut depends on intercellular signalling between the endodermal and mesodermal cells of the gut. In particular, the differentiation of intestinal mesoderm into smooth muscle has been suggested to depend on signals from adjacent endodermal cells. One candidate mediator of endodermally derived signals in the embryonic hindgut is the secreted protein Sonic hedgehog (Shh). The Shh gene is expressed throughout the embryonic gut endoderm with the exception of the pancreatic bud endoderm, which instead expresses high levels of the homeodomain protein Ipf1/Pdx1 (insulin promoter factor 1/pancreatic and duodenal homeobox 1), an essential regulator of early pancreatic development. Here, we have examined whether the differential expression of Shh in the embryonic gut tube controls the differentiation of the surrounding mesoderm into specialised mesoderm derivatives of the small intestine and pancreas. To test this, we used the promoter of the Ipf1/Pdx1 gene to selectively express Shh in the developing pancreatic epithelium. In Ipf1/Pdx1-Shh transgenic mice, the pancreatic mesoderm developed into smooth muscle and interstitial cells of Cajal, characteristic of the intestine, rather than into pancreatic mesenchyme and spleen. Also, pancreatic explants exposed to Shh underwent a similar program of intestinal differentiation. These results provide evidence that the differential expression of endodermally derived Shh controls the fate of adjacent mesoderm at different regions of the gut tube. PMID- 9368765 TI - Hematopoietic stem cells expand during serial transplantation in vivo without apparent exhaustion. AB - Whether hematopoietic stem cells can proliferate without limit, or whether their regenerative capacity declines with repeated division, has been debated for decades. Prevailing opinion favours an intrinsic 'decline', a view based on the finite degree to which murine bone marrow can be serially transplanted, the diminished self-renewal of spleen colony-forming cells (CFU-s) subjected to repeated passage, and the failure of stem cells to regenerate to normal levels after even a single transplantation. However, serial transfer experiments did not specifically monitor input and output of long-lived stem cells (long-term reconstituting cells, LTRCs), leaving competing interpretations unresolved. We have re-examined the issue by quantitating 7-12 month LTRCs during sequential transplantations. Although these cells recovered to only 4% of normal levels after primary bone marrow transplantation, at each passage they increased around 10-fold relative to the amount transplanted, attaining an estimated cumulative expansion of 8400-fold over the original input after four transfers. Expansion was limited by transfer of increasing numbers of marrow cells and specifically of LRTCs, suggesting an extrinsically determined ceiling to stem cell growth. Conversely, expansion was enhanced in vivo by administration of stem cell factor (SCF, c-kit ligand) and interleukin-11. The results challenge the view that expansion of passaged stem cells is limited by exhaustion, and indicate that augmentation after transplant is limited by extrinsic mechanisms whose effects are reversible either by further transfer of the stem cells into irradiated hosts or by administration of exogenous cytokines. PMID- 9368767 TI - Regulated neurite tension as a mechanism for determination of neuronal arbor geometries in vivo. AB - Transection and displacement experiments on isolated neurons in culture have shown that their neurites are under tension. Such tensile forces might be important in determining the structures of neuronal arbors in vivo. It has also been proposed that tension mechanisms generate the global folding patterns of the brain. It has been difficult to determine whether tension is important in vivo, however, because most neuronal arbors have complex three-dimensional structures that cannot be perturbed in a controlled manner. Here we describe a situation in which tension can be demonstrated and perturbed in an intact central nervous system (CNS). In the embryonic CNS neuropil of the grasshopper Schistocerca americana, the axon of a local serotonergic interneuron known as s1 forms a characteristic bifurcation. The geometry of this bifurcation node is highly conserved between embryos and held constant during development. Current models for the development of such geometries usually propose that they are created and maintained by neurite adhesion to localized substrates. Here we show that the structure of the s1 bifurcation node is likely to be determined by balanced tension between three fixed points. This was revealed by selectively transecting each of the branches that intersect at the node. Transections are followed by a rapid restructuring ('snapping') of the node geometry. PMID- 9368766 TI - Photoactivation turns green fluorescent protein red. AB - In the few years since its gene was first cloned, the Aequorea victoria green fluorescent protein (GFP) has become a powerful tool in cell biology, functioning as a marker for gene expression, protein localization and protein dynamics in living cells. GFP variants with improved fluorescence intensity and altered spectral characteristics have been identified, but additional GFP variants are still desirable for multiple labeling experiments, protein interaction studies and improved visibility in some organisms. In particular, long-wavelength (red) fluorescence has remained elusive. Here we describe a red-emitting, green absorbing fluorescent state of GFP that is generated by photoactivation with blue light. GFP can be switched to its red-emitting state easily with a laser or fluorescence microscope lamp under conditions of low oxygen concentration. This previously unnoticed ability enables regional, non-invasive marking of proteins in vivo. In particular, we report here the use of GFP photoactivation to make the first direct measurements of protein diffusion in the cytoplasm of living bacteria. PMID- 9368768 TI - Trials and tribulations: ethical dilemmas in HIV therapy. PMID- 9368770 TI - Transplantation tolerance--putting the pieces together. PMID- 9368769 TI - HIV co-receptor identification: good or bad news for drug discovery? PMID- 9368771 TI - Bone marrow chimerism and transplantation tolerance. AB - Engraftment of allogeneic or xenogeneic pluripotent hematopoietic stem cells into nonmyeloablated but immunodepleted (preconditioned) recipients can produce a state of immunological tolerance to donor and host. Host and donor hematopoietic cells entering the thymus ensure deletion of both donor- and host-reactive thymocytes. Additional mechanisms are involved in tolerance induced in recipients that are not immunodepleted. Grafting of donor thymic tissue to thymectomized recipients is an alternative approach for inducing central T cell tolerance without the requirement for engraftment of donor hematopoietic stem cells. During the past year, advances have been made in understanding both the requirements for preconditioning and the mechanisms of tolerance induction in the above transplantation models. PMID- 9368772 TI - The CD40 pathway in allograft rejection, acceptance, and tolerance. AB - The CD40 pathway plays a critical role at many levels of the sensitization and effector phases of allograft rejection. In addition to the important signaling role of this pathway for T cell help and effector function, recent evidence suggests that the CD40 pathway can directly co-stimulate T cells, independently of its effect on the B7-CD28 pathway. PMID- 9368773 TI - T cell inactivation and cytokine deviation promoted by anti-CD3 mAbs. AB - Fc receptor nonbinding anti-CD3 monoclonal antibodies show promise for clinical application, in that they suppress graft rejection without the toxicity associated with conventional anti-CD3 antibody therapy. Recent studies suggest that the mechanism of soluble anti-CD3 antibody mediated immunosuppression involves partial signaling, induced cytokine deviation and Th1 cell inactivation. PMID- 9368774 TI - Minor histocompatibility antigens. AB - The existence of transplantation antigens, in addition to those encoded by genes in the MHC, has been known for over half a century. The molecular identification of these additional minor histocompatibility (H) antigens lagged behind that of their MHC counterparts, largely because minor H antigens are recognised by T cells and not by antibodies. In the past year, however, new minor H antigens have been identified at both the genetic and protein level and include Uty, a second novel gene encoding a male-specific epitope in mice, a novel autosomal gene encoding each of the H-13 alleles of mice, and a second male-specific epitope encoded by the SMCY gene. PMID- 9368775 TI - Gene therapy and allotransplantation. AB - The potential of gene therapy to deliver therapeutic protein agents, such as cytokines, antibodies and recombinant ligands, in vivo has stimulated interest in many biological fields, including transplantation. Regarding the latter, gene transfer strategies could be used to deliver molecules with immunomodulating activity to the graft itself or to defined sites in the recipient to prevent graft rejection or ischaemic injury or to induce tolerance to donor alloantigens. Any of these options offers many advantages over the systemic delivery of immunosuppressive agents currently employed in transplantation. PMID- 9368776 TI - Peptide-mediated immunosuppression. AB - New insights into the mechanisms of allorecognition and the interactions of the TCR with the MHC molecule-peptide complex on antigen presenting cells have focused attention on developing novel biological strategies to modify the alloimmune response. Peptides derived from various regions of MHC class I and II molecules and structure-based peptides have demonstrated immunomodulatory effects both in vitro and in vivo. Their binding sites and mechanisms of action are under active investigation. Trials in human transplant recipients, with an MHC class I peptide have already begun. PMID- 9368777 TI - Chronic remodeling pathology in grafts. AB - The theoretical basis of chronic allograft rejection remains poorly defined, but is clearly associated with the development of a relatively unique vasculopathy, transplant vascular sclerosis (TVS). The hypothesis that TVS is the cause of chronic rejection has yet to be proven, although it is widely accepted. Accumulating data suggest that, at best, the hypothesis is incomplete. The challenge for transplant investigators is to review the currently available data and to develop a testable, revised version of the hypothesis that explains both the antigen-dependent and antigen-independent contributions to graft vascular remodeling, and that encompasses all reasonable alternative mechanisms of graft failure. PMID- 9368778 TI - T cell defined tumor antigens. AB - T cell defined antigens have now been characterized in a large variety of tumor types, in both mice and humans. An increasing number of these antigens appear to result from tumor-specific mutations, and some of these mutations may be implicated in oncogenesis. The priority is now to demonstrate that immunization against some of these antigens is clinically valuable for antitumor therapy, and the first results of clinical pilot studies are now emerging. PMID- 9368779 TI - HLA class I specific inhibitory receptors. AB - All human natural killer cells and some memory T cells express HLA class I receptors, so-called natural killer cell receptors (NKRs), a receptor class that in the past few years has been shown to include several members of the immunoglobulin superfamily and the C-type lectin CD94-NKG2A complex. NKR ligand mediated cross-linking leads to the recruitment and activation of a tyrosine phosphatase involved in downregulating the phosphorylation of effector molecules involved in cell triggering. Thus, NKR engagement leads to the inhibition of different NK and T cell functions. PMID- 9368780 TI - Prospects for adoptive T cell therapy. AB - Since the establishment of methods to isolate genes encoding cytotoxic T lymphocyte defined tumor antigens, several antigens have been identified and characterized for suitability as target antigens for immunotherapy. The development of innovative strategies to generate T cells targeting these antigens and lessons learned from clinical trials of adoptive immunotherapy of viral diseases should facilitate the design of clinical trials for specific adoptive immunotherapy of cancer. PMID- 9368781 TI - Serological identification of human tumor antigens. AB - Using the antibody repertoire of cancer patients for the systematic search for human tumor antigens, a plenitude of new human tumor antigens has been identified demonstrating that many human tumors elicit multiple immune responses in the autologous host. The abundance of serologically defined human tumor antigens facilitates the identification of T cell dependent antigens and provides a basis for peptide and gene therapy vaccine strategies in a wide variety of human cancers. PMID- 9368782 TI - Antibody-based immunological therapies. AB - Clinical research in the area of antibody-based tumor-targeted therapy has been driven for many years by the prospect of identifying cell surface antigens with sufficient restrictive tissue expression patterns to allow for the selective and specific accumulation of antibody in tumor tissue. Few, if any, such antibody antigen systems have been identified which can effectively deliver a large fraction of an administered therapeutic agent to metastatic cancer. Despite this limitation, however, a greater understanding of the biological and physiological principles of tumor-targeted therapy has resulted in successful antibody-based therapy of lymphoma, colon cancer and breast cancer in recent clinical trials. PMID- 9368783 TI - Paraneoplastic syndromes. AB - Paraneoplastic syndromes (i.e. organ/tissue disorders associated with cancer) affecting the nervous system are thought to be the result of an autoimmune response triggered by specific cancer antigens. Several of these antigens have recently been identified and include the Hu, Yo and Ri proteins, with the Hu antigens being the best studied. Immunization of animals with HuD has been shown to retard the growth of HuD-positive neuroblastomas. In addition, the presence of anti-HuD antibody in humans with small-cell lung cancer predicts the slow growth of the tumor. The associated neurological disorders, however, limit the use of these and other antigens with similar characteristics in cancer vaccines. PMID- 9368784 TI - Transplantation. PMID- 9368785 TI - Cancer. PMID- 9368786 TI - Emergence of new pathogens as a function of changes in host susceptibility. AB - A pathogen may emerge as an important public health problem because of changes in itself or its transmission pathways. Alternatively, a microorganism may emerge as a pathogen or acquire new public health importance because of changes in host susceptibility to infection. Factors influencing host susceptibility within the population as a whole include increases in the number of immunocompromised patients; increased use of immunosuppressive agents, particularly among persons receiving cancer chemotherapy or undergoing organ transplantation; aging of the population; and malnutrition. In considering the emergence of foodborne pathogens and designing interventions to limit their spread, the susceptibility of these population subgroups to specific infections should be taken into account. PMID- 9368787 TI - Foodborne disease control: a transnational challenge. AB - In the globalized political economy of the late 20th century, increasing social, political, and economic interdependence is occurring as a result of the rapid movement of people, images, values, and financial transactions across national borders. Another consequence of the increase in transnational trade, travel, and migration is the greater risk of cross-border transmission of infectious diseases. As the world becomes more interconnected, diseases spread more rapidly and effectively. With more than one million people crossing international borders every day, and with the globalization of food production, manufacturing, and marketing, the risk of infectious disease transmission is greater. Economic globalization has also increased the need for governmental budget austerity, and consequent national preparedness has been eroded. The emergence of new infectious diseases, as well as the reemergence of old ones, thus represents a crucial transnational policy issue. These problems cannot be resolved by national governments alone; they require international cooperation. This article analyzes the role of foodborne disease surveillance programs, nationally and internationally, in the control of foodborne diseases. PMID- 9368789 TI - Foodborne Diseases Active Surveillance Network (FoodNet). PMID- 9368788 TI - Strategies for rapid response to emerging foodborne microbial hazards. AB - The foodborne outbreak paradigm has shifted. In the past, an outbreak affected a small local population, had a high attack rate, and involved locally prepared food products with limited distribution. Now outbreaks involve larger populations and may be multistate and even international; in many the pathogenic organism has a low infective dose and sometimes is never isolated from the food product. Delay in identifying the causative agent can allow the outbreak to spread, increasing the number of cases. Emergency intervention should be aimed at controlling the outbreak, stopping exposure, and perhaps more importantly, preventing future outbreaks. Using epidemiologic data and investigative techniques may be the answer. Even with clear statistical associations to a contaminated food, one must ensure that the implicated organism could logically and biologically have been responsible for the outbreak. PMID- 9368790 TI - Indices of oxidative stress in urine of patients undergoing coronary artery bypass grafting. AB - Indices of oxidative stress in urine were measured in twenty patients undergoing elective coronary artery bypass grafting. Hypoxanthine, xanthine and uric acid were measured in urine, as markers of ischaemia together with malondialdehyde, which is a marker for lipid peroxidation. To correct for renal dysfunction during coronary artery bypass grafting the creatinine concentration was measured in urine and plasma. The creatinine concentration in plasma increases significantly during surgery, from 84 +/- 23 mumol/l to 133 +/- 52 mumol/l, whereas the creatinine concentration in urine decreases significantly, from 8.29 +/- 4.45 mmol/l to 2.70 +/- 1.01 mmol/l, during reperfusion. For reasons of comparison, the values of the observed measurements in urine are expressed per mol creatinine. The hypoxanthine and xanthine excretions both increase significantly, from 15.0 +/- 7.3 and 10.9 +/- 5.7 mmol/mol creatinine, respectively, after induction of anaesthesia to a maximum of 33.1 +/- 16.7 and 17.4 +/- 11.1 mmol/mol creatinine, respectively, during reperfusion. The malondialdehyde excretion increases significantly, from 1.38 +/- 0.80 mmol/mol creatinine after induction of anaesthesia to a maximum of 3.87 +/- 1.87 mmol/mol creatinine during reperfusion. The purines and malondialdehyde in urine (expressed as a ratio of creatinine), increase during coronary artery bypass grafting as a consequence of oxygen mediated tissue injury. PMID- 9368791 TI - In vivo inhibition of nitric oxide synthase by bisisothiouronium and bisguanidinium salts. AB - The ability of two S,S'-(alkane-1,omega-diyl) bisisothiouronium dibromides, three N,N'-(alkane-1, omega-diyl) bis guanidinium dinitrates and N,N'-bis (3 guanidinopropyl)piperazine dinitrate to inhibit constitutive (i.e. endothelial and neuronal forms) and inducible forms of nitric oxide synthases has been evaluated in vivo. These compounds, synthesized by two of us (J. C. L. and C. S.), have been tested in vivo; they were administered simultaneously with an irritant (carrageenan lambda) into the pleural cavity. The amount of nitrites collected 0.5 and 7 hours after this injection can be considered as an indicator of nitric oxide (NO) production. According to previous data, the first harvesting time can be related to activation of constitutive NO synthases and the second to activation of inducible NO synthases. These substances significantly inhibited nitrite production as did 2-methyl-2-thiopseudourea sulphate, previously described as a potent inhibitor of NO synthases and considered as the reference compound. The inhibiting effect varied according to the chemical structure of the compounds. Results were significantly different from controls at 0.5 h only with the S,S'-(octane-1,8-diyl) bisisothiouronium dibromide and the S,S'-(nonane-1,9 diyl) bisisothiouronium dibromide at the highest concentration, N,N'-(heptane-1,7 diyl) bisguanidinium dinitrate and N,N'-bis (3-guanidinopropyl)piperazine dinitrate. At 7 h, all the results were significantly different from controls, with a major effect observed with N,N'-(heptane-1,7-diyl) bisguanidinium dinitrate. The most active substances exerted similar effects to the reference substance. PMID- 9368792 TI - Serum phospholipases A2 in patients undergoing panproctocolectomy because of severe ulcerative colitis. AB - A major role has been proposed for group II phospholipase A2 in the pathogenesis of local and generalised inflammatory reactions. Elevated catalytic activity and mass concentrations of this enzyme have been found in serum and tissue samples of the colon in patients with active ulcerative colitis. The cellular source(s) of group II phospholipase A2 in the blood circulation is (are) unknown. In the current prospective study, we investigated the mass concentration of group II phospholipase A2 and the catalytic activity concentration of phospholipase A2 in serial serum samples of 15 consecutive patients who underwent a standard panproctocolectomy operation for severe ulcerative colitis. Both the catalytic activity concentrations of phospholipase A2 and the mass concentrations of group II phospholipase A2 increased rapidly in serum samples to maximum values on the first postoperative day and then decreased (p = 0.002 and p < 0.001, respectively) in patients who recovered uneventfully. Three patients had postoperative complications that further increased the enzyme concentrations at the time of respective complications. The pattern of group II phospholipase A2 mass concentration profiles was similar to the profiles of C-reactive protein. The results show that the removal of the large bowel does not eliminate the potential to secrete group II phospholipase A2 into the blood circulation in these patients. Secretion of group II phospholipase A2 into the circulation after surgery seems to be a normal host response to a major abdominal operation and postoperative complications. Consequently, we conclude that the large bowel is not an important source of group II phospholipase A2 in sera of patients with ulcerative colitis. The results also support the assumptions that the catalytic activity of phospholipase A2 in serum is attributable to group II phospholipase A2 and that this enzyme is an acute phase protein. PMID- 9368793 TI - Determination of lamotrigine, carbamazepine and carbamazepine epoxide in human serum by gas chromatography mass spectrometry. AB - A method for the identification and quantification of the antiepileptics lamotrigine, carbamazepine and carbamazepine epoxide (active metabolite) in human serum is described. In refractory epilepsy the combination of carbamazepine and lamotrigine was recently developed to a modern therapeutic concept. The goal of this paper is therapeutic drug monitoring (TDM) of these substances. Serum was extracted with a quick precipitation method using a modified commercial extraction-kit and analysed by gas chromatography mass spectrometry (GC-MS). A gas-chromatographic temperature-pressure programme was developed that allowed the determination of lamotrigine by gas chromatography mass spectrometry. A reference spectrum of pure lamotrigine is herewith published for the first time. A new mass spectra library was created to support the identification of the antiepileptics in human serum. In the Specified Ions Monitoring mode (SIM) a detection limit below the therapeutic range and recoveries above 90% were obtained. Comparison of results obtained by GC-MS or a commercially available high performance liquid chromatographic (HPLC) method (for lamotrigine) and a fluorescence polarisation immunoassay (FPIA) (for carbamazepine) from spiked serum samples showed disagreement of no more than 10% between the methods and demonstrated the accuracy of the new method. In addition, quantitative determinations of these antiepileptics in samples from patients under anticonvulsive therapy showed a strong linear correlation with r2 = 0.961 for carbamazepine and r2 = 0.964 for lamotrigine. Only two from a total of 46 results differed by more than 10%. Our method for quantifying lamotrigine in serum seems to be highly specific and capable of measuring lamotrigine in patients on single therapy, as well as on add on therapy with carbamazepine or carbamazepine epoxide. No interference from other coadministered drugs was detected. PMID- 9368794 TI - Enzymatic determination of unbound D-mannose in serum. AB - Mannose is an aldohexose component of a number of glycoproteins in cellular membranes and blood plasma. Free (unbound) mannose is a normal blood plasma constituent and its concentration is elevated in diabetes mellitus and chronic glomerulonephritis. We devised an enzymatic method for the determination of free mannose in which mannose is converted to glucose-6-phosphate and measured spectrophotometrically using glucose-6-phosphate dehydrogenase and nicotinamide adenine dinucleotide phosphate (NADP). Accumulation of reduced NADP in the assay was verified by spectral analysis and by finding rapid disappearance of absorbance at 340 nm on addition of glutathione reductase and oxidized glutathione into the reaction mixture. The method necessitates prior removal of glucose from the samples. This we accomplished using glucose-6-phosphate dehydrogenase and a surplus amount of NADP, followed by elimination of reduced NADP by acidification of the reaction mixture. The assays may be run in parallel for expediency. Concentration of free mannose in serum was 18.5 +/- 5.5 mumol/l in healthy fasting female adults. The analytical recovery was 90.2 +/- 10.2% and the between-run imprecision was 13.5% (18.5 +/- 5.5 mumol/l, mean +/- SD) and 10.4% (75.3 +/- 10.3 mumol/l). The assay showed rectilinearity up to 220 mumol/l, which covers the measuring range to which the mannose concentrations in normal and clinical samples may be expected to fall. PMID- 9368795 TI - Comparison of the troponin T and troponin I ELISA tests, as measured by microplate immunoassay techniques, in diagnosing acute myocardial infarction. AB - We describe an improved procedure using a standard microplate immunoassay reader to measure the concentration of troponin T in human serum. We also describe an immunoassay for troponin I in serum. Only 160 microliters of serum are needed for a single analysis of each troponin. For comparison, creatine kinase MB mass analysis in serum was performed with a commercial luminometric method. From 95 apparently healthy people the following values were obtained: creatine kinase MB mass 2.6 +/- 1.2 micrograms/l, troponin T 0.027 +/- 0.025 microgram/l and troponin I 0.03 +/- 0.031 microgram/l. We compared the results of troponin T and troponin I methods with each other, as well as with those of creatine kinase MB mass measured in 48 patients with verified acute myocardial infarction and in 60 control patients with non-cardiac chest pain. The correlation between troponin T and troponin I values was 0.91 for the total material and 0.94 for 48 patients with acute myocardial infarction. Troponin I showed better earlier sensitivity than troponin T (p = 0.043). In nine patients in the control group, creatine kinase MB mass exceeded the reference limit of 5.0 micrograms/l, while in two patients the cut-off limit of 10.0 micrograms/l was also surpassed, pointing to non-specificity. In the group of infarct patients, the highest serum creatinine value was 193 mumol/l, whereas in the control group it was 406 mumol/l. The sera of patients with impaired renal function without any cardiac failure showed no increase in troponin T and troponin I values. In conclusion, serum creatine kinase MB mass and troponin I seem to confirm an acute myocardial infarction more rapidly than does troponin T; troponin I has the highest cardiac specificity. PMID- 9368796 TI - An alternative analysis for crossover studies that accounts for between-group disparities in drug response. AB - BACKGROUND: In crossover clinical trials comparing completely different treatments, patients tend to fall into different populations: those who respond better to treatment 1 and those who respond better to treatment 2. The correlation between treatment response in such trials is negative. The current ANCOVA analysis for crossover studies does not allow for correlations being negative, and is therefore not adequate for testing in this kind of trials. OBJECTIVE OF STUDY: To study whether matrix algebra provides a more appropriate approach for this purpose. RESULTS AND CONCLUSIONS: Using a mathematical model as well as hypothesized examples, it is demonstrated that matrix algebra of 2 pairs of cells of the same order not only allows for negative correlations in a crossover design but also provides enough power to test both the treatment and carryover effect. PMID- 9368797 TI - Whole blood folate concentrations: comparison between Stratus Folate (DADE) and radioassay (DPC) methods. AB - The analytical performance of the Stratus Folate assay for intra-erythrocyte folate determination in normal subjects and in patients affected by folate related diseases was compared with that of the radioassay (DPC) routinely employed by us. Folate concentrations were measured in freshly obtained EDTA whole blood from 100 subjects. Haemolysis was performed with the appropriate lysis reagent. In addition, to compare two different haemolysis procedures folate determination was carried out in 51 samples haemolysed according to the two procedures in parallel. Data were analyzed using Wilcoxon's test and standardized principal component analysis. Stratus Folate assay and radioassay performances were comparable in terms of analytical characteristics as well as in individual intraerythrocyte folate values across the range of whole blood concentrations examined in the survey. Significant differences were detected between the two different haemolysis procedures only for the radioassay. In conclusion, we observed no significant differences between the two folate determination methods despite their different analytical principles, which indicates the suitability of routine use of the automated non-isotopic Stratus Folate assay for clinical purposes. Moreover, with the latter assay the laboratory staff could choose the more convenient haemolysis procedure. PMID- 9368798 TI - Potential interfering substances on Falcor-600 and Dax-48 analytical systems. AB - The increasing availability and use of automatic analysers in clinical chemistry have revealed a number of endogenous interferences. We evaluated the effect of bilirubin, haemolysis and lipaemia on the Falcor-600 analytical system (Menarini Diagnostics) and the Dax-48 (Bayer Diagnostic). We studied the potential endogenous interferences in the measurement of serum glucose, urea, creatinine, cholesterol, triacylglycerols, total bilirubin, total protein, aspartate aminotransferase, alanine aminotransferase and gamma-glutamyltransferase on both analysers; and albumin, direct bilirubin, uric acid, inorganic phosphorus, iron, calcium, magnesium, chloride, sodium, potassium, alkaline phosphatase, amylase, lactate dehydrogenase and creatine kinase on the Dax-48. We followed the guidelines of the Spanish Society of Clinical Biochemistry and Molecular Pathology. Bilirubin samples were prepared using bovine bilirubin, and studied in the concentration range of 20 to 400 mumol/l. For haemolysis, the pool was spiked with a diluted haemolysate of human red cells to achieve a concentration range of 10 to 120 mumol/l of haemoglobin. Lipaemia was studied using samples spiked with Intralipid, a fat emulsion, at concentrations from 1 g/l to 6 g/l (3 to 18 mumol/l of triacylglycerols). PMID- 9368799 TI - A new assay for soluble transferrin receptors in serum: time for standardisation. PMID- 9368800 TI - The European Register for Clinical Chemists. (European Communities Confederation of Clinical Chemistry, Working Group on Registration). AB - To ensure freedom of movement in the European Union, a limited number of professions is regulated by a so-called Sectorial Directive; all other disciplines, including clinical chemistry, fall under a General Directive. However, clinical chemists in the EU wish their specialty to be more specifically regulated; this means that common standards of education, training, experience and compliance with continuing professional developments must be guaranteed. Therefore, the European Communities Confederation of Clinical Chemistry (EC4) is about to implement the European Register for clinical chemists, and has composed a guide to this Register. The document describes the conditions for entry to specialty training, the minimum standards for registration (university education and postgraduate vocational training with a minimum total of eight years), the competencies of those qualifying for registration, and the operation of the register. Registration guarantees professional and managerial competencies; the title conferred is "European Clinical Chemist". EC4 recognises the existing national registers as far as they are based on the minimal requirements as indicated. An EC4 Register Commission (EC4RC) will maintain and control the European Register, supported by National Clinical Chemistry Registration Committees (NCCRC). An NCCRC controls the quality of the education in each country and assesses candidates. An individual (EU citizen or non-EU citizen trained in an EU country) applies privately for the European Register to EC4RC and, where applicable, the application is accompanied by a document from the NCCRC of the country of registration, stating that the applicant has the necessary qualifications. For EU citizens trained outside the EU the final decision is with EC4RC; non-EU citizens not trained in an EU country are not eligible for registration. Registration is renewed once every five years. PMID- 9368801 TI - European Communities Confederation of Clinical Chemistry guide to the EC4 register: European Clinical Chemist. PMID- 9368802 TI - International Union of Pure and Applied Chemistry and International Federation of Clinical Chemistry. Properties and units in the clinical laboratory sciences. VI. Properties and units in IOC prohibited drugs (IUPAC-IFCC recommendations 1997). PMID- 9368803 TI - International Union of Pure and Applied Chemistry and International Federation of Clinical Chemistry, Committee on Nomenclature. Properties and Units (C-NPU): properties and units in the clinical laboratory sciences. IX. Properties and units in trace elements (IFCC-IUPAC technical report 1997). PMID- 9368804 TI - Dietary triglycerides, up to 40 g/meal, do not affect preformed vitamin A bioavailability in humans. AB - OBJECTIVE: Assessing the effect of the dose of dietary triglycerides on preformed vitamin A (retinyl esters) bioavailability in humans. DESIGN: Four test meals containing 15,000 RE retinyl-palmitate and either 0, 15, 30 or 40 g added triglycerides were ingested by eight healthy volunteers, at different days and in a randomized order. SETTING: The study was done in the Hospital Sainte Marguerite, Marseille, France. SUBJECTS: Eight healthy male volunteers were recruited by advertisement. INTERVENTION: Blood samples were collected every hour for seven hours after the test meals intake. Serum and chylomicron (Svedberg flotation unit > 1000) were prepared by centrifugation and retinyl esters were measured by HPLC. RESULTS: The serum retinyl ester response was not significantly lower after the intake of the meal without added triglycerides (7944 +/- 3262 nmol/L h) than after the intake of the fat meals (10012 +/- 2182, 7869 +/- 3157 and 10777 +/- 2067 nmol/L h for the 15, 30 and 40 g-fat meal, respectively), indicating that the serum retinyl ester response was not related to the amount of meal triglycerides. Chylomicron retinyl linoleate response stepwise increased when the amount of meal triglycerides increased while retinyl palmitate and retinyl stearate responses reached a maximum since 15 g triglycerides. Postprandial serum retinol concentration did not change whatever the meal ingested. CONCLUSIONS: (i) a significant amount of preformed vitamin A is apparently absorbed when ingested with trace amount of meal triglycerides only; (ii) meal triglycerides, up to 40 g/meal, do not increase preformed vitamin A bioavailability; (iii) the retinyl ester pattern recovered in the chylomicrons, and probably the esterification process of retinol, is affected by the amount of meal triglycerides; (iv) postprandial retinol homeostasis is not affected by dietary triglycerides. PMID- 9368805 TI - Determinants of the nutritional status of vitamin E in a non-smoking Mediterranean population. Analysis of the effect of vitamin E intake, alcohol consumption and body mass index on the serum alpha-tocopherol concentration. AB - OBJECTIVE: Study was conducted in order to investigate the association of vitamin E intake and other factors with plasma alpha-tocopherol concentration in a non smoking Mediterranean population. DESIGN: A cross-sectional study was conducted in a subsample of a representative sample of the Catalan population. SUBJECTS: Sample size was 143 men and women, aged between 18 and 75 y, and final response rate reached 61.9% of the initial sample. INTERVENTIONS: Serum alpha-tocopherol concentration standardized by serum total lipids was used as a proxy of the nutritional status of vitamin E. Vitamin E intake and alcohol consumption were estimated by a replicated 24 h recall method. Dietary data were collected in two different periods, winter and summer, in order to account for seasonal variation in nutrient intake, and were corrected for random within-person variability in order to account for day-to-day variation in nutrient intake. Multivariate linear regression models were fitted in order to estimate the determinants of serum alpha-tocopherol concentration. RESULTS: In this population study, for each one mg increase in vitamin E intake, serum alpha-tocopherol concentration increased, on average, 0.66 micromol/L, after adjusting for age, gender, Body Mass Index (BMI), alcohol consumption and energy intake. BMI also influenced significantly serum alpha-tocopherol concentration, whereas alcohol intake, age and gender did not show significant associations with serum alpha-tocopherol. CONCLUSIONS: The study showed that vitamin E nutritional status was associated to vitamin E intake and BMI in non-smokers. PMID- 9368806 TI - Nutrition, anaemia, geohelminth infection and school achievement in rural Jamaican primary school children. AB - OBJECTIVE: To determine whether nutritional status, anaemia and geohelminth infections were related to school achievement and attendance in Jamaican children. DESIGN: A cross-sectional study using a randomly selected sample. SUBJECTS: Eight hundred children aged 9-13 y randomly selected from those enrolled in grade 5 in 16 primary schools in rural Jamaica. RESULTS: The mean height-for-age of the children was -0.37 z-score +/- 1.0 s.d. with 4.9% having heights-for-age < -2 s.d. of the NCHS references. Anaemia (Hb < 11 g/dl) was present in 14.7% of the children, 38.3% were infected with Trichuris trichiura and 19.4% with Ascaris lumbricoides. Achievement levels on the Wide Range Achievement Test were low, with children performing at grade 3 level. In multilevel analyses, controlling for socioeconomic status, children with Trichuris infections had lower achievement levels than uninfected children in spelling, reading and arithmetic (P < 0.05). Children with Ascaris infections had lower scores in spelling and reading (P < 0.05) Height-for-age (P < 0.01) was positively associated with performance in arithmetic. Ascaris infection (P < 0.001) and anaemia (P < 0.01) predicted poorer school attendance. CONCLUSION: Despite mild levels, undernutrition and geohelminth infections were associated with achievement, suggesting that efforts to increase school achievement levels in developing countries should include strategies to improve the health and nutritional status of children. PMID- 9368807 TI - Serum phospholipid fatty acid composition and habitual intake of marine foods registered by a semi-quantitative food frequency questionnaire. AB - OBJECTIVE: To examine the relation between consumption of fish and fish products registered by a comprehensive food frequency questionnaire and the composition of fatty acids in serum phospholipids. DESIGN: Cross-section study. SETTING: Cardiovascular screening centre in Trondheim, Mid-Norway. SUBJECTS: Of 256 eligible women 242 agreed to participate in the present study. Altogether 234 middle-aged women (91.4%) completed the questionnaire and gave a valid blood sample. RESULTS: Total frequency consumption of fish for dinner showed only weak association with serum phospholipid fatty acid composition. In separate analyses of lean and fatty fish, consumption of fatty fish was negatively associated with n-6 and positively associated with n-3 fatty acids in serum phospholipids, while no significant associations were found for lean fish consumption. Cod liver oil consumption was strongly related to the phospholipid fatty acid composition. The associations improved moderately when adding portion size information. Spearman's correlation coefficient between dietary intake of eicosapentaenoic acid (EPA) and serum phospholipid EPA was 0.58, and Spearman's correlation coefficient between intake of docosahexaenoic acid (DHA) and serum phospholipid DHA was 0.53. CONCLUSIONS: This study suggests that in populations with a high consumption of fish and cod liver oil, habitual intake can be reflected in serum phospholipids. However, as the fat content of fish is highly variable, separate registration of lean and fatty fish consumption is needed. PMID- 9368808 TI - Body mass index and prevalence of obesity changes among Kuwaitis. AB - OBJECTIVES: To compare temporal changes in BMI, overweight (BMI > 25 kg/m2) and obesity (BMI > 30 kg/m2) between two periods, among adult Kuwaitis. DESIGN: Comparison of two independent cross-sectional samples of Kuwaitis studied in 1980 81 and 1993-94. SUBJECTS: 2067 (896 men and 1171 women) and 3435 (1730 men and 1705 women) adult Kuwaitis (aged > or = 18 y), drawn from primary health care (PHC) clinics and studied for nutritional assessment and for prevalence of obesity in 1980-81 and 1993-94, respectively. MEASUREMENTS: Weight was measured in kilograms and height in meters to obtain the body mass index (BMI), which is the weight in kilograms divided by the height in meters squared (kg/m2). BMI > 25 and > 30 kg/m2 were classified as overweight and obesity, respectively. RESULTS: Mean BMI (kg/m2) increased significantly (P < 0.001) by 10.0 and 6.2% (2.5 and 1.7 kg/m2) among men and women, respectively. Prevalence of overweight and obesity (BMI > 25 and > 30 kg/m2) increased by 20.6 and 15.4% and by 13.7 and 8.4% among men and women, respectively. After controlling for sociodemographic differences between the two study periods, mean BMI was 2.0 and 1.6 kg/m2 higher in 1993-94 than in 1980-81 among men and women, respectively. Prevalence of overweight and obesity (BMI > 25 and > 30 kg/m2) also increased among both genders between the two periods (OR = 2.1, 95% CI 1.7-2.7 and OR = 1.9, 95% CI 1.5-2.4, for men and OR = 2.2, 95% CI 1.6-3.0 and OR = 1.4, 95% CI-1.0-1.9, for women). CONCLUSIONS: BMI, prevalence of overweight and obesity increased among Kuwaitis between 1980-81 and 1993-94, probably due to the effects of modernization, affluence, increased food consumption and the concomitant changes to sedentary lifestyles. The rate of temporal changes in BMI and obesity were higher, by comparison, in Kuwait than in selected other countries. PMID- 9368809 TI - Intrahousehold allocation of energy intake among children under five years and their parents in rural Bangladesh. AB - OBJECTIVE: This study assesses intrahousehold allocation of energy in rural Bangladesh and tests the hypothesis that, when daily energy intake is adjusted for energy expenditure, no age or gender bias will be apparent in intrahousehold energy allocation. DESIGN: Data were collected at two-month intervals over a one year study. SETTING: Four villages in Matlab Thana, rural Bangladesh. SUBJECTS: Two hundred and seven children up to 5 y of age and their 145 mothers and 123 fathers. INTERVENTIONS: Data included six measurements of observed 24 h dietary energy intake and physical activity recorded from waking to sleeping. Total daily energy expenditure was derived using the factorial method. RESULTS: Women's energy intake ranged from 75-88% of the FAO/WHO recommended energy intake over the six periods of data collection, significantly less (P < 0.0001) than the men's (range 89-114%). Although the women had moderate levels of physical activity, frequent pregnancies and long lactation periods increased their energy needs. Among children no longer breast fed, energy consumption, unadjusted for energy expenditure, provided 86-108% of the FAO/WHO recommended energy intake by weight. CONCLUSIONS: Women consistently received less of their energy requirements than either their children or their husbands. PMID- 9368810 TI - Lifestyle intervention in people with insulin-dependent diabetes mellitus (IDDM). AB - OBJECTIVE: To investigate the impact of intensive lifestyle education on dietary practices, exercise and metabolic measurements in people with insulin-dependent diabetes mellitus (IDDM). DESIGN: Sixty-one volunteer subjects with IDDM were randomised to intensive (Group 1) or standard (Group 2) education programmes for six months. During a second six month period of observation Group 1 subjects received routine surveillance for their condition and those in Group 2 were given intensive advice (phase 2). Current insulin regimens were modified to optimise glycaemic control before the start of the intervention phase. Nutrient intakes, weight, blood pressure, glycated haemoglobin (HbA1), plasma lipids, lipoproteins and maximal oxygen consumption (VO2 max) were measured at the time of recruitment and at three monthly intervals during the trial and phase 2. SETTING: Department of Human Nutrition at the University of Otago. RESULTS: Glycated haemoglobin decreased significantly in both groups between recruitment and randomisation, the improvement being sustained during the six months of the randomised trial and for group 1 during the six months of post trial observation. A further decrease was seen in Group 2 during the second six month period when they were given intensive advice. Comparable changes were seen with total and low density lipoprotein (LDL) cholesterol in Group 1 during the trial, but significant decreases were only seen in Group 2 in association with intensive intervention (phase 2). These changes occurred in parallel with increases in intakes of carbohydrate and monounsaturated fatty acids, a reduction in intakes of total and saturated fat, and an improvement in maximum oxygen consumption. CONCLUSIONS: A lifestyle programme for people with IDDM results in modest changes in diet and exercise habits sufficient to improve measures of glycaemic control and lipoprotein mediated risk of coronary heart disease independent of changes in insulin regime. More innovative approaches to achieve lifestyle changes are required to meet current recommendations which in turn are likely to produce even greater beneficial changes than those observed here. PMID- 9368811 TI - Estimates of the sources of variation (variance components) of bioelectric impedance and anthropometric measurements in an epidemiological case-control study of breast cancer. AB - OBJECTIVE: This study investigated the variability of anthropometric measurements and body fat estimated by bioelectric impedance analysis. Subsequently the methods were applied in a case-control study to investigate the association with breast cancer. DESIGN, SUBJECTS: The study group included 50 consecutive cases and 75 age-matched controls from the same area. The variation was investigated in 50 healthy women from the control group, who were repeatably measured using standardised measurement procedures, and the variation between-subjects, within subjects, between-observers, and within-observers were estimated. RESULTS, CONCLUSIONS: The study showed that the variance components between-subjects were 64-99% of the total variance. The variables of skinfold thicknesses were characterised by having the highest relative observer variation and having many unavailable values that were out of the range of the Harpenden callipers. The mean body fat by bioelectric impedance analysis was 31.2%, and the total coefficient of variation 23%, while the variance components related to subject time, observer and measurement were 98.4%, 1.1%, 0.2%, and 0.4%, respectively. The body fat was significantly correlated with the variables of skinfold thicknesses. We decided to exclude the variables of skinfold thicknesses from the case-control study, and for the other variables to measure each subject only at one time by one observer. The case-control part of the study indicated a non significant increase in body weight in the postmenopausal breast cancer patients (mean difference 3.6 kg; confidence interval from -0.9 kg to 8.0 kg). Similarly the body fat tended to be higher in the breast cancer patients (mean difference 1.2%; confidence interval from -1.6% to 4.0%). PMID- 9368812 TI - A model to standardise mortality of severely malnourished children using nutritional status on admission to therapeutic feeding centres. AB - OBJECTIVE: To determine a simple model to calculate the number of deaths which could be expected in a therapeutic feeding centre from the height, weight and oedema of children on admission. DESIGN: Admission weight, height, presence of oedema of the children and outcome were prospectively recorded. SETTING: Data were recorded in 18 feeding centres set-up during emergency operations in Africa. Ten of the feeding centres were selected, a priori, as reference centres and eight centres as test centres. SUBJECTS: Data for 3858 children were recorded. 837 children absconded from the centres and were excluded from the analysis. Analysis was performed on data from 2753 children who left the centre after recovery and 268 children who died during treatment. INTERVENTIONS: The relation between the risk of death and, anthropometric measurements and presence of oedema has been determined in a previous paper. The maximum likelihood estimate of the constant of the model was determined from global analysis of the data of the reference centres. The model was applied to the data of the reference and test centres. RESULTS: The model to predict the individual probability of death was: P(death) = 1/(1 + exp[-(20.63 - 9.99 1n(weight/height1.74) + 1.36 oedema)]) The predicted number of deaths was close to the recorded number of deaths for each reference centre. For three of the eight test centres there was a significant excess of observed deaths over predicted. CONCLUSION: This model can be easily used by the supervisor of a centre to assess the expected number of deaths during treatment of malnutrition from simple measurements on children that are routinely taken on admission and thus help to determine the nature of variation in observed mortality rates. PMID- 9368813 TI - Fat preferences, dietary fat intake and body composition in children. AB - OBJECTIVE: To examine the relationship between fat preference, dietary intake data and body composition in children. SUBJECT AND METHODS: Subjects studied were 88 children aged 9-12 y from two elementary schools in Ohio. Measures for dietary intake and body composition were obtained by 3 day diet records, anthropometrics, triceps and subscapular skinfolds. Fat preference data was assessed by hedonic rating of high and low fat snack foods. RESULTS: Data indicate that children who preferred the high fat snack items had high dietary fat intakes (r = 0.57, P < 0.05). Tricep skinfold measurement and BMI correlated positively with high fat food preferences (r = 0.51 and r = 0.46 P < 0.05). CONCLUSIONS: These data suggest preference for high fat foods may occur due to diet composition and that increased adiposity may be associated with higher relative fat intakes. PMID- 9368814 TI - The effect of withdrawal of food iron fortification in Sweden as studied with phlebotomy in subjects with genetic hemochromatosis. AB - OBJECTIVES: The iron fortification of food in Sweden, the highest in the world, was withdrawn 1st January 1995, because the effect upon target groups was considered to be uncertain. We wanted to study the effect of such a dietary experiment. DESIGN: Comparative cross over study. SETTING: Out patient service and Blood Bank. SUBJECTS: Sixteen men aged 24-73 y on maintenance phlebotomy after treatment for iron overload. One was excluded because of inflammatory disease. INTERVENTIONS: Quantitative phlebotomy with serial measurements of Hb conc., % transferrin saturation and serum ferritin concentration. MAIN OUTCOME MEASURES: Iron absorption was measured by phlebotomy during two periods, with and without iron fortification. 1 g Hb = 3.4 mg Fe. RESULTS: Iron absorption was significantly reduced (P < 0.001) when iron fortification was withdrawn from a mean of 4.27 +/- 1.2 to 3.63 +/- 1.1 mg/d. The difference of 0.65 mg/d (95% c.i. 0.32-0.97) corresponds to the fraction of iron derived from fortification. Intervals between donations had to be extended from 59 +/- 15 to 69 +/- 17 d (P < 0.01) to avoid induction of iron deficiency anemia. The iron content of the fortified diet averaged 15.4 mg/d, of which the fortified fraction constituted 4.1 mg/d (27%). The relative bioavailability of carbonyl iron used as fortificant was 38%. CONCLUSIONS: The relative bioavailability of carbonyl iron used as fortificant was higher than previously reported. Target groups such as menstruating females will probably be affected by a higher prevalence of iron deficiency when food is no longer fortified. People with genetic hemochromatosis will accelerate into clinical disease at a slower rate. PMID- 9368815 TI - The double isotope tracer method is a reliable measure of fractional zinc absorption. PMID- 9368816 TI - Carbohydrate and fat balance: separate existences or an intimate relationship? PMID- 9368817 TI - Brown fat thermogenesis in rats fed high-fat diets enriched with n-3 polyunsaturated fatty acids. AB - OBJECTIVE: To examine the possible involvement of an increase in diet-induced thermogenesis from brown adipose tissue (BAT) in the n-3 polyunsaturated fatty acids (n-3 PUFA) induced limitation of the development of white fat pads during high-fat feeding. DESIGN: Rats fed for four weeks on a low-fat/high-carbohydrate diet (C group) or high-fat diet without n-3 PUFA (REF group), with eicosapentaenoic acid (EPA group), with docosahexaenoic acid (DHA group) or with a mixture of these two fatty acids (MIX group). MEASUREMENTS: Epididymal and retroperitoneal fat pad mass, BAT composition, Guanosine 5'-diphosphate (GDP) binding and uncoupling protein (UCP) content were measured in the five groups of rats. RESULTS: The masses of retroperitoneal and epididymal white fat pads were lower in the groups fed n-3 PUFA than in the C and REF groups. The total BAT GDP binding was 1.6 times higher in the MIX and EPA groups than in the REF group. The BAT from the EPA group presented an enrichment in mitochondria compared to the C and REF groups whereas the BAT from the DHA and REF groups presented a hyperplasia and an increase in thermogenic activity of the mitochondria compared to the C group. The higher thermogenic activity of BAT was observed in the MIX group and is due to hyperplasia and to an increase in thermogenic activity of mitochondria. CONCLUSIONS: n-3 PUFA induce a marked stimulation of BAT thermogenic activity without changes in the UCP content compared to a high-fat diet without n-3 PUFA. The mixture of EPA and DHA has the more pronounced effect while EPA and DHA seem to act in synergy on BAT thermogenesis via different mechanisms. PMID- 9368818 TI - The relative effectiveness of two styles of educational package to change practice nurses' management of obesity. AB - OBJECTIVE: To examine the impact of two styles of educational package on practice nurses' management of obesity. SUBJECTS AND MEASURES: A questionnaire was completed by 66 practice nurses concerning their obesity related beliefs and the content and style of their weight related practices before and one month after being randomly allocated to either the 'learner centred' group (who received a leaflet and were invited to attend an interactive seminar), the 'expert group' (who received the leaflet) or the control group. At the one month follow up, practice nurses were also asked to give a brief questionnaire to five consecutive patients, who they saw for weight loss advice, concerning the content and style of the consultation. After 6 months, practice nurses, and patients were sent a questionnaire about their consultation style and weight loss, respectively. RESULTS: The packages had no differential effects on practice nurses' beliefs about obesity. However, practice nurses in the 'learner group' reported spending longer on their consultations and being more patient centred. Their patients rated themselves as more satisfied with the consultation and reported that they were offered calorie controlled diets less often. In contrast, practice nurses in the 'expert group' reported giving weight loss advice more frequently, being less patient centred and their patients reported greater confidence in, and likelihood of, weight loss and reported that they were more likely to be offered traditional weight loss interventions. The packages had no differential effects on patient weight. CONCLUSION: Practice nurses' and patients' beliefs and behaviour and the style of their interactions can be changed by both expert and learner centred educational packages. The style of packages should be chosen in terms of both the available resources and the desired outcomes. PMID- 9368819 TI - Noradrenaline-induced lipolysis in isolated mesenteric, omental and subcutaneous adipocytes from obese subjects. AB - OBJECTIVE: The action of noradrenaline on human mesenteric, omental and subcutaneous adipocytes was compared. We also determined whether regional differences in the noradrenaline-effect were linked to variations in adrenoceptor subtype function. DESIGN: The lipolytic effects of different concentrations of noradrenaline (beta 1-, beta 2-, beta 3- and alpha 2-adrenoceptor agonist), isoprenaline (beta 1-, beta 2- and beta 3-adrenoceptor agonist) and selective beta 1-, beta 2- and beta 3-adrenoceptor agonists (dobutamine, terbutaline and CGP 12177, respectively) were studied in adipocytes isolated from the three adipose tissue regions in the same subject. In addition, the effect of the alpha 2-adrenoceptor antagonist, yohimbine, was studied on noradrenaline-induced glycerol release. SUBJECTS: Thirteen otherwise healthy obese subjects (nine females, four males). RESULTS: The noradrenaline-induced lipolytic response did not differ between omental and mesenteric adipocytes but was 50% higher than in subcutaneous adipocytes (P < 0.05). Furthermore, noradrenaline sensitivity and intrinsic activity (in relation to isoprenaline) were higher in the two visceral fat cells than in the subcutaneous fat cells. The intrinsic activity of noradrenaline increased close to that of isoprenaline when yohimbine was added to the incubation system. Isoprenaline sensitivity was five times higher in the two visceral fat cells than in the subcutaneous fat cells. For CGP 12177, sensitivity and intrinsic activity did not differ between mesenteric and omental adipocytes, but was higher in these two regions when compared to subcutaneous adipocytes. For dobutamine and terbutaline no significant regional differences were found. CONCLUSION: beta 3-adrenoceptor action is enhanced and alpha 2-adrenoceptor action is decreased in both mesenteric and omental adipocytes as compared to subcutaneous adipocytes. However, the two visceral fat depots show no difference in adrenoceptor function. The difference in beta 3- and alpha 2-adrenoceptor function might explain why noradrenaline induced lipolysis is increased in the two visceral fat depots, as compared to the subcutaneous fat depot. PMID- 9368820 TI - Regulation of adipose tissue lipoprotein lipase in young and old rats. AB - OBJECTIVE: Changes in tissue lipoprotein lipase have been reported in several of the metabolic disorders commonly associated with ageing, like insulin resistance, obesity and impaired hormonal balance. We have investigated the effect of normal ageing on the nutritional regulation of lipoprotein lipase (LPL) in rat tissues. MEASUREMENTS: In the first experiment, LPL activity and immunoreactive mass were measured in epididymal and perirenal adipose tissue, and soleus and heart muscle tissue. In the following experiments we focused on epididymal adipose tissue. RESULTS: In young rats (aged 29 d, 87 +/- 5 g), fasting for 24 h decreased LPL activity in epididymal and perirenal adipose tissue to 31% and 51% of fed control, respectively, while LPL mass increased to 146% and 261%, respectively. Consequently, LPL specific activity (activity/mass ratio) decreased to 20% of control. Other tissues studied did not show any large changes in LPL specific activity with the nutritional state. This suggests that the mechanism responsible for the down-regulation of LPL specific activity is specific for adipose tissue. The down-regulation was gradually blunted with increasing age and was non existent in the old rats (aged 265 d, 564 +/- 14 g). LPL in soleus muscle from young rats was regulated by another mechanism, and was associated with a large increase in LPL activity and mass during fasting (297% and 458% of fed control). Also, this mechanism did not exist in soleus muscle from old rats. Prolonging the fasting period of the old rats to 96 h did not induce the changes in adipose tissue or soleus muscle LPL seen in the young rats. CONCLUSION: The results indicate that the nutritional regulation of LPL in adipose tissue and soleus muscle changes during normal ageing. PMID- 9368821 TI - VLCD plus dietary and behavioural support versus support alone in the treatment of severe obesity. A randomised two-year clinical trial. AB - OBJECTIVES: To determine whether 12 initial weeks on a Very Low Calorie Diet (VLCD) included in a two-year support program is associated with better long term weight loss maintenance than a dietary and behavioural support program alone. Additionally, to identify characteristics associated with successful treatment or attrition, which can be used in selecting individuals likely to respond to VLCD programs. DESIGN: Randomised clinical trial. SETTING: Two Swedish out-patient clinics. SUBJECTS: 113 obese men and women aged 37-58 y, body mass index (BMI) > 32.0 kg/m2, participating in the Swedish Obese Subjects-(SOS) study. INTERVENTIONS: One group received VLCD for 12 initial weeks plus regular dietary and behavioural support over two years while the other group received two years of the same supportive program only. MAIN OUTCOME MEASURE: Weight loss after two years treatment. RESULTS: Both treatment groups maintained highly significant weight losses at two years but the initial VLCD-treatment appeared to have given no significant long term benefit compared to the supportive program. Examination of selected demographic, psychosocial and dietary characteristics showed that the VLCD-approach was more effective than the supportive strategy alone in men and possibly in individuals sharing household with only one person. High initial hunger-score was associated with attrition, irrespective of treatment. CONCLUSION: A VLCD-program including long term dietary and behavioural support is a successful treatment for some severely obese subjects, especially men. Further research should be directed towards matching treatments to individuals in order to improve the high recidivism rates generally following weight loss attempts. PMID- 9368822 TI - Simple anthropometric indexes and cardiovascular risk factors in Chinese. AB - OBJECTIVE: Obesity is a major public health problem due to its associations with multiple cardiovascular risk factors. Although there are sophisticated methods, such as imaging, to document total body fat and its distributions, anthropometric measurements remain important in clinical practice. We examined the relationships between cardiovascular risk factors and the three commonest anthropometric measurements for obesity, body mass index (BMI), waist-hip ratio (WHR) and waist circumference (WC), in Hong Kong Chinese subjects. DESIGN AND SETTING: The data are obtained from a prevalence survey for glucose intolerance and lipid abnormality in a representative Hong Kong Chinese working population. All employees from a public utility company and a regional hospital were invited to participate. SUBJECTS: There were 1513 subjects (910 men and 603 women, mean age +/- s.e.m.: 37.5 +/- 0.2 y). All of them had no significant past medical history. MEASUREMENTS: BMI, WHR and WC of the 1513 subjects were assessed for their relationships with various cardiovascular risk factors. These include blood pressure, fasting and 2 h plasma glucose and insulin, glycated haemoglobin, total cholesterol, triglyceride, high density and low density lipoprotein cholesterol, and urine albumin concentration. RESULTS: After age adjustment, all three anthropometric indexes were significantly correlated with the major cardiovascular risk factors in both men and women. When BMI, WHR and WC were analysed according to quartiles, there was a significant trend for blood pressure, plasma triglyceride, fasting and 2 h plasma glucose and insulin to increase, and high density lipoprotein cholesterol to decrease, with increasing obesity after adjustment for age and smoking. Using stepwise regression analysis with the three indexes as independent variables, most of the variance in blood pressure, plasma lipid, insulin, glucose and urinary albumin concentration were explained either by WC or WHR. In women, BMI was the main explanatory variable for reduced high density lipoprotein cholesterol. CONCLUSIONS: In Hong Kong Chinese, BMI, WHR and WC provide important information in assessing cardiovascular risks. In men, central adiposity as reflected by WC and to some extent, WHR, explained most of the variance in blood pressure, plasma glucose, lipid, insulin and albuminuria. In women, all three indexes reflecting general and central obesity contribute to the variance in these risk factors. PMID- 9368823 TI - Alarmingly high prevalence of obesity in Curacao: data from an interview survey stratified for socioeconomic status. AB - OBJECTIVE: The aim of the article is to report the prevalence of obesity, abdominal fatness and waist circumference in different socioeconomic classes in Curacao. DESIGN: In 1993/1994 a health interview survey (the Curacao Health Study) was carried out among a random sample (n = 2248, response rate = 85%) of the adult non-institutionalized population of Curacao. METHODS: We analyzed the association between obesity (BMI > or = 30), abdominal fatness (waist hip ratio (WHR) > or = 0.95 for men, WHR > or = 0.80 for women) waist circumference (WC > or = 100 cm for men, WC > or = 91 cm for women) and socioeconomic status (SES) by age adjusted logistic regressions, for men and women separately. RESULTS: The prevalence of obesity was about 27%: 36% of the women and 19% of the men were obese. An at risk WHR was reported among 62.2% of the women and among 20.4% of the men. A WC above the cut-off point was reported for 44.3% women and 25.3% men. Compared to women of higher SES, the lower SES women have a two to three times higher risk of a BMI, WHR or WC exceeding the cut-off points. Among men, no statistically significant difference between an increased BMI, WHR or WC and SES factors was found. The overlap between the three measures is large, about 56% of the women scored similarly on all three measurements. Among men the overlap is even greater (73%). CONCLUSIONS: The prevalence of obesity in Curacao is alarming. Low SES women are at the greatest risk of an increased BMI, WHR or WC. The obesity figures can be placed between industrialized societies and less modernized cultures. Action and additional research on the prevention of obesity in Curacao are deemed necessary. The cut-off points in our study for WC in the non-white population are preliminary and need to be elucidated further. PMID- 9368824 TI - Energy intake and net weight gain in pregnant women according to body mass index (BMI) status. AB - OBJECTIVE: To investigate whether body mass index (BMI) is related to energy intake during pregnancy, and whether BMI, energy intake and other factors are related to net weight gain. DESIGN: Longitudinal, duration of pregnancy. SUBJECTS: 156 healthy pregnant women residing in Quedlinburg county, Germany. METHODS: Weighed 7 d food records and standardized anthropometric measures in the first, second and third trimester. The analysis of variance (ANOVA) statistical technique was used to analyze differences in energy intake, net weight gain and birthweight across BMI groups, and the Cochran-Mantel Haenszel test was used to analyze food group intake by BMI group. RESULTS: Women at the highest level of BMI were significantly less often in the high energy intake category than women at the medium or low level of BMI (15% vs 36% and 48%). Net weight gain during pregnancy was independently influenced by BMI status and energy intake. Women at the highest level of BMI gained significantly less weight (4.2 kg) from first to third trimester than women at the medium or low levels of BMI (weight gains of 6.2 kg and 5.9 kg, respectively). Women with a low daily energy intake gained 4.6 kg during pregnancy, while women with medium and high energy intakes gained 6.0 kg and 6.1 kg, respectively. Examination of net weight gain simultaneously across BMI and parity groups revealed a much lower net weight gain among multigravid women at the highest BMI level (3.3 kg). Primigravid high BMI women, in contrast, gained 6.9 kg, whereas multigravid and primigravid women at medium and low BMI levels gained average of 4.8 kg and 6.5 kg, respectively. The mean birth weight in the three BMI groups did not differ and was not influenced by age, marital status, education, parity or smoking. CONCLUSION: Because other studies have shown that weight gain during pregnancy increases the risk of subsequent overweight, multigravid high BMI women may prevent an increased weight retention after pregnancy due to lower weight gain in the current gestation. A lower caloric diet may help to accomplish a lower weight gain during pregnancy in overweight women without increased risk of low birth weight infants. These findings indicate further investigation of the associations between BMI, parity and caloric intake during pregnancy are needed to increase understanding of factors affecting subsequent weight gain. PMID- 9368825 TI - The effect of weight reduction on the surface electrocardiogram: a prospective trial in obese children and adolescents. AB - OBJECTIVE: Controversial data exist on the effect of obesity and weight reduction on surface electrocardiographic parameters. The purpose of this study was to analyze electrocardiograms of obese children in the course of short-term weight reduction. DESIGN: Prospective trial over a period of three weeks with a conventional low calorie diet containing a mean of 525 +/- 109 kcal. SUBJECTS: Thirty-three children, 17 girls and 16 boys with a mean age of 12.2 +/- 1.7 y and an overweight of 25.4-102%, mean 54.2 +/- 15.6%. MEASUREMENTS: Before the onset of therapy and thereafter, body weight, blood chemistry and 12 lead electrocardiographic evaluations were performed. RESULTS: The mean loss of body weight was 5.7 +/- 1.6 kg resulting in a mean decrease in overweight of 13.5 +/- 3.4%. Blood chemistry analyses revealed no significant changes except for cholesterol, triglycerides and uric acid. All electrocardiograms were within normal limits, however, a change in the electrocardiographic pattern was noted after weight loss. Heart rate (84 +/- 14 vs 64 +/- 11 beats per min, P < 0.0001) and QT interval (418 +/- 20 msec vs 391 +/- 22 msec, P < 0.0001) decreased and there was a tendency towards a rightward shift of the frontal plane QRS axis and a leftward shift of the horizontal plane QRS axis. CONCLUSION: Weight reduction in obese children and adolescents is associated with significant changes in the electrocardiographic pattern. These changes may only be detected by intraindividual comparison. Reduction of heart rate and shortening of the QT interval in the course of weight reduction may be of clinical significance by reducing the cardiovascular risk profile, including the risk of potentially fatal arrhythmias in obese subjects. PMID- 9368826 TI - Familial resemblance for abdominal visceral fat: the HERITAGE family study. AB - OBJECTIVES: Abdominal visceral fat (AVF) is considered a risk factor for diabetes, atherogenic lipid profiles and hypertension. However, little is known about the genetic contribution to AVF as compared to total body fat. DESIGN: AVF was assessed by computerized tomography, and total body fat (fat mass) was assessed by underwater weighing in 86 families participating in the Heritage Family Study. All family members were sedentary at baseline examination. The familial factors underlying the variability in age-adjusted AVF, age-fat mass adjusted AVF and age-adjusted fat mass, were assessed using a familial correlation model. RESULTS: The maximal heritability (including genetic and familial environmental effects) for AVF was comparable before (47%) and after (48%) adjusting for fat mass, and was 55% for fat mass itself in these sedentary families. Spouse correlations were significant for fat mass and for AVF prior to, but not after, adjustment for fat mass. CONCLUSIONS: These results confirm the only previous study which investigated the familial aggregation of AVF (both in pattern and magnitude), suggesting that the factors underlying AVF in these sedentary families may be similar to those in the population at large. Although both genetic and familial environmental factors probably influence each of fat mass and AVF, there appears to be a predominantly genetic etiology for the visceral component which is independent of total body fat. These findings imply that some individuals are more at risk then others because of an inherited tendency to store abdominal fat viscerally rather than subcutaneously. PMID- 9368827 TI - Association of a low density lipoprotein receptor microsatellite variant with obesity. AB - OBJECTIVE: To determine whether a microsatellite polymorphism located towards the 3' end of the low density lipoprotein receptor gene (LDLR) is associated with obesity. DESIGN: A cross-sectional case-control study. SUBJECTS: One hundred and seven obese individuals, defined as a body mass index (BMI) > or = 26 kg/m2, and 163 lean individuals, defined as a BMI < 26 kg/m2. MEASUREMENTS: BMI, blood pressure, serum lipids, alleles of LDLR microsatellite (106 bp, 108 bp and 112 bp). RESULTS: There was a significant association between variants of the LDLR microsatellite and obesity, in the overall tested population, due to a contributing effect in females (chi 2 = 12.3, P = 0.002), but not in males (chi 2 = 0.3, P = 0.87). In females, individuals with the 106 bp allele were more likely to be lean, while individuals with the 112 bp and/or 108 bp alleles tended to be obese. CONCLUSIONS: These results suggest that in females, LDLR may play a role in the development of obesity. PMID- 9368828 TI - Estimation of the cost savings resulting from the use of ursodiol for the prevention of gallstones in obese patients undergoing rapid weight reduction. AB - BACKGROUND: Morbidly obese patients enrolled in a rapid weight reduction program are at a high risk of developing gallstones. Two multicenter, placebo-controlled, randomized, double-blind trials have demonstrated that the prophylactic use of ursodiol in males and females 18 to 70 years of age is effective for the prevention of gallstone formation in this patient population. This study examines the cost consequences associated with the prophylactic use of ursodiol. METHODS: A medical decision analysis model for the prophylactic administration of ursodiol in morbidly obese patients undergoing rapid weight reduction by either gastric bypass surgery or very-low-calorie-diet, was developed through the use of data from two clinical trials and review of the related literature. The expert opinion of clinicians from the fields of internal medicine, gastroenterology and surgery were solicited. Financial data for the charges associated with cholecystectomies, physician fees and ursodiol were obtained from current financial databases. RESULTS: The model demonstrates that the prophylactic administration of ursodiol, in morbidly obese patients undergoing rapid weight reduction, results in cost savings. Sensitivity analysis was performed to illustrate that the cost savings achieved by the prophylactic use of ursodiol were valid over a realistic range of charges and assumptions. CONCLUSION: The decision model may allow health care decision makers to apply their own data to the model to determine the cost savings obtainable through the prophylactic use of ursodiol in patients undergoing rapid weight reduction. PMID- 9368829 TI - Food preferences in Prader-Willi syndrome, normal weight and obese controls. AB - OBJECTIVE: The aim of this work was to assess the specific food type (high carbohydrate, high fat, high protein) preference profiles of individuals with Prader-Willi syndrome (PWS), obese controls and normal weight individuals. DESIGN: Subjects tasted a food predominantly high in carbohydrate, a food predominantly high in protein and a food predominantly high in fat over repeated trials and indicated their most preferred, second preferred and least preferred foods. Specific items tested on a given trial were counterbalanced in a block randomized fashion. SUBJECTS: These were 12 individuals with Prader-Willi syndrome, 12 matched obese controls (obese, but otherwise normal) and 14 normal weight subjects. MEASUREMENTS: The basic data were expressed as a proportion of each food type selected as most preferred over the total 27 trials. RESULTS: PWS subjects preferred high carbohydrate foods over high protein foods and high protein foods over high fat foods. These subjects demonstrated a statistically reliable difference in preference for high carbohydrate foods over high fat foods. However, normal weight and obese control subjects demonstrated no difference in food preferences. The only significant between-group comparisons were between PWS subjects and obese controls, with the PWS group showing a significantly greater preference for high carbohydrate foods than obese controls. CONCLUSIONS: The obesity of PWS was shown to have a significant and distinctly different food preference profile from normal weight and obese controls. The differences in food preference between the obese PWS and non-PWS subjects is in accord with the growing recognition of functional subgroups within the obese population, that may have not only differing underlying etiologies, but also distinct behavioral profiles of ingestion. PMID- 9368830 TI - Relations of total and abdominal adiposity to muscle sympathetic nerve activity in healthy older males. AB - OBJECTIVES: We recently reported that skeletal muscle sympathetic nerve activity (MSNA) is related to total body and abdominal fatness in a pooled population of young and older males. Both MSNA and adiposity increase with age. Thus, it is not clear if the relation between MSNA and adiposity exists among older adults and if the age-related increase in MSNA is explained by increases in adiposity. We therefore tested the hypotheses that: 1) among older men, those with higher total body fatness and abdominal adiposity have higher MSNA and 2) MSNA is not different in healthy young and older men with similar total body and/or abdominal fatness. DESIGN: Older healthy men (63 +/- 1 y) were separated into higher and lower groups of body fat (26.9 +/- 0.8%, n = 9 vs 21.3 +/- 1.1, n = 10; P < 0.0001) and waist circumference (96.4 +/- 3.5 cm, n = 8 vs 86.2 +/- 1.5, n = 8; P < 0.01). Younger controls (26 +/- 1 y) were then matched with those in the older lower groups for %body fat (21 +/- 1.1%, n = 10) or waist circumference (86.2 +/- 0.8 cm, n = 10). MEASUREMENTS: Total body fat was determined by hydrodensitometry, abdominal adiposity by waist circumference and resting MSNA by microneurography. RESULTS: Among the older subjects those in the higher %body fat and waist circumference groups had higher (P < 0.02) MSNA (47 +/- 3 and 48 +/- 4 bursts/min, respectively) than those in the lower groups (37 +/- 2 and 38 +/- 3 bursts/min). MSNA was directly related to %body fat (r = 0.52, P = 0.03) and waist circumference (r = 0.64, P = 0.007) in the older groups. MSNA was greater (P < 0.001) in the older-lower groups than in the young controls matched for %body fat (23 +/- 2 bursts/min) or waist circumference (24 +/- 3 bursts/min). CONCLUSIONS: 1) among healthy older men, higher levels of total body and/or abdominal adiposity are associated with higher levels of MSNA and 2) the age related elevation in MSNA is reduced but not abolished when differences in adiposity are eliminated. PMID- 9368831 TI - Dehydroepiandrosterone-sulfate (DHEAS) reduces adipocyte hyperplasia associated with feeding rats a high-fat diet. AB - OBJECTIVE: To determine if chronic administration of a low level of dehydroepiandrosterone-sulfate (DHEAS) (10 micrograms/ml drinking water) attenuates adiposity in male Osborne-Mendel rats fed low-fat (11% of kcals) vs high fat (46% of kcals) diets. DESIGN: Rats were randomly assigned to one of four treatment groups for 6 wk in this 2 x 2 factorial study. The main effects tested were diet (low vs high fat) and DHEAS (- or +). SUBJECTS: Male Osborne-Mendel rats (initial body wt approximately 265 g). MEASUREMENTS: Adipocyte mass, size and number from two major fat depots (retroperitoneal, epididymal); mass of one subcutaneous adipose depot (inguinal); serum levels of triglycerides, insulin, glucose and DHEAS; brown adipose tissue (BAT) mass; body weight gain, food and water consumption, and residual carcass composition. RESULTS: DHEAS treatment had no effect on weight gain, food consumption or water intake. DHEAS-treated rats fed the high-fat diet had smaller fat pads containing fewer adipocytes and less carcass lipid than the non DHEAS-treated rats fed the high-fat diet. In contrast, DHEAS-treated rats fed the low-fat diet had similar levels of adipose tissue mass and cellularity compared to control animals fed the low-fat diet. CONCLUSION: Administration of a low dose of DHEAS (10 micrograms/ml or 0.8 mg/kg body wt/d) in the drinking water of young male Osborne-Mendel rats fed a high-fat diet for 6 wk reduced carcass lipid, fat depot mass and retroperitoneal and epididymal adipocyte number compared to their high-fat-fed cohorts. In this study, the antiobesity effects of DHEAS were specific to the level of dietary fat used. PMID- 9368833 TI - Resting metabolic rate in young Polynesian and Caucasian women. AB - OBJECTIVE: To investigate whether resting metabolic rate (RMR) differs between Caucasian and Polynesian women. DESIGN: Cross-sectional comparison. SUBJECTS: Eighty-two (42 Caucasian, 40 Polynesian) healthy women aged between 18 and 27 y. MEASUREMENTS: RMR (indirect calorimetry) and body composition (fat-free mass and fat mass derived from oxygen-18 dilution measurement of total body water). RESULTS: RMR was similar in the Caucasian (6956 +/- 1291 (s.d.) kJ/d) and Polynesian (7125 +/- 1290 kJ/d) groups while fat-free mass was significantly lower in the Caucasian group (45.3 +/- 6.8 vs 51.0 +/- 6.4 kg, P < 0.002). After adjustment for fat-free mass and fat mass, RMR was lower in the Polynesian than the Caucasian groups (6783 +/- 904 vs 7281 +/- 901 kJ/d, P = 0.023). CONCLUSION: The significantly lower relative RMR observed in Polynesian compared to Caucasian women may predispose Polynesian women to eventual onset of obesity. PMID- 9368832 TI - Loss of weight restores GLUT 4 content in insulin-sensitive tissues of monosodium glutamate-treated obese mice. AB - OBJECTIVE: To investigate the effect of weight loss on GLUT 4 content of insulin sensitive tissues of obese mice. SUBJECTS: Mice were made obese by neonatal treatment with monosodium glutamate (MSG). In addition, one group of obese animals was submitted to a caloric restriction to promote 20% weight loss (MSG L). Both groups were compared to age-matched control mice. MEASUREMENTS: Anthropometric data, glycaemia and insulinaemia were measured. The GLUT 4 protein was assessed by Western blotting analysis in white (WAT) and brown (BAT) adipose tissue, and skeletal (SM) and cardiac (CM) muscles. RESULTS: The MSG mice were very obese according to their morphometric analysis, showing moderate hyperglycaemia with severe hyperinsulinaemia, and reduced (P < 0.001) glucose/insulin (G/I) ratio. The procedure for weight loss promoted a significant (P < 0.001) reduction of both glycaemic and insulinaemic levels, and an increase in G/I ratio. Compared to control animals, the GLUT 4 content in obese MSG mice, was decreased by 30% (P < 0.05) in SM and CM, by 80% (P < 0.001) in BAT and in different subcellular membrane fractions of WAT. On the other hand, transporter protein content was restored to normal levels in MSG-L animals. CONCLUSION: The reduced GLUT 4 content of insulin sensitive tissues from MSG-treated obese mice is recovered by a 20% loss in weight. This mechanism can be involved in the observed increase of insulin sensitivity. PMID- 9368834 TI - Influence of chronic Naltrexone treatment on growth hormone and insulin secretion in obese subjects. AB - OBJECTIVE: Recent studies have demonstrated the restoration of a normal 24 h GH profile induced by a reduction of insulinaemia after weight loss, suggesting a reciprocal relationship between plasma insulin and GH concentrations. We aimed to clarify if an opiate-induced reduction in plasma insulin could affect GH secretion in obesity. DESIGN: We have studied the insulin response to an oral glucose tolerance test (OGTT) and the GH response to GHRH before and after prolonged treatment with Naltrexone (NTX). C-peptide, IGF-I, IGFBP-3 plasma levels and the IGF-I/IGFBP-3 molar ratio were also determined. SUBJECTS: Twelve obese women (aged 25-41 y; Body mass index (BMI): 31-39 kg/m2) and six lean normal women (aged 25-38; BMI: 19.8-23.1 kg/m2). MEASUREMENT: GH was determined by the IRMA method; insulin, C-peptide, IGF-I and IGFBP-3 were assayed by the RIA method. For molar comparison between IGF-I and IGFBP-3 we have considered 30.5 kDa the molar weight of IGFBP-3. Results are expressed as mean +/- s.e.m. RESULTS: We observed a significant decrease in basal concentration of both insulin (230.1 +/- 34.9 vs 133.2 +/- 16.9 pmol/L; P < 0.005) and C-peptide (3.7 +/- 0.3 vs 2.4 +/- 0.1 micrograms/L; P < 0.02). No modifications in the insulin secretory response to the OGTT were observed. A significant increase of the GHRH induced GH peak response (7.7 +/- 1.4 vs 19.7 +/- 3.1 micrograms/L; P < 0.01) and GH-AUC (533 +/- 151 vs 1415 +/- 339 micrograms/L/120 min; P < 0.01) was found after NTX treatment. A negative correlation was found between basal insulin and GH peak values, both before (r = -0.641, P = 0.027) and after NTX (r = -0.714, P = 0.013). No modifications were found in IGF-I, IGFBP-3 and IGF-I/IGFBP-3 molar ratio. Moreover, NTX affected neither the insulin response to OGTT or IGF-I, IGFBP-3 and IGF-I/IGFBP-3 molar ratio in a group of six lean controls. Conversely, NTX significantly reduced the GH response to GHRH, when expressed as both peak and AUC values. CONCLUSIONS: The opiate antagonist significantly reduced basal insulin concentrations and augmented the GH response to GHRH in obese subjects. In the absence of modifications in IGF-I and IGFBP-3 plasma levels and their molar ratio, we propose that insulin may exert a negative feedback on GH secretion. PMID- 9368835 TI - Gender differences in body fat content are present well before puberty. AB - To determine whether gender differences in body fat could be detected in prepubertal children using dual energy X-ray absorptiometry (DEXA), body composition was measured in 20 healthy boys aged 3-8 y matched for age, height and weight with 20 healthy girls. Although boys and girls did not differ in age, height, weight, body mass index (BMI) or bone mineral content, the boys had a lower percentage of body fat (13.5 +/- 5.1 vs 20.4 +/- 6.1%, P < 0.01), a lower fat mass (3.2 +/- 2.0 vs 4.9 +/- 3.1 kg, P < 0.01), and a higher bone-free lean tissue mass (18.6 +/- 4.3 vs 17.0 +/- 3.5 kg, P < 0.01) than the girls. Girls had approximately 50% more body fat than the boys. This is the first DEXA study to show that boys aged 3-8 y have less body fat than girls of similar age, height and weight. Thus, this technology demonstrates that significant gender differences in body composition are evident, well before the onset of puberty. PMID- 9368836 TI - Expression of c-fos in the rat brainstem after exposure to hypoxia and to normoxic and hyperoxic hypercapnia. AB - In this study, Fos immunohistochemistry was used to map brainstem neuronal pathways activated during hypercapnia and hypoxia. Conscious rats were exposed to six different gas mixtures: (a) air; (b) 8% CO2 in air; (c) 10% CO2 in air; (d) 15% CO2 in air; (e) 15% CO2 + 60% O2, balance N2; (f) 9% O2, balance N2. Double staining was performed to show the presence of tyrosine hydroxylase. Hypercapnia, in a dose-dependent way caused Fos expression in the following areas: caudal nucleus tractus solitarius (NTS), with few labeled A2 noradrenergic neurons; noradrenergic A1 cells and noncatecholaminergic neurons in the caudal ventrolateral medulla; raphe magnus and gigantocellular nucleus pars alpha (GiA); many noncatecholaminergic (and relatively few C1) neurons in the lateral paragigantocellular nucleus (PGCl), and in the retrotrapezoid nucleus (RTN); locus coeruleus (LC), external lateral parabrachial and Kolliker-Fuse nuclei, and A5 noradrenergic neurons at pontine level; and in caudal mesencephalon, the ventrolateral column of the periaqueductal gray (vlPAG). In most of these nuclei, hypoxia also induced Fos expression, albeit generally less than after hypercapnia. However, hypoxia did not cause labeling in RTN, juxtafacial PGCl, GiA, LC, or vlPAG. After normoxic hypercapnia, more labeled cells were present in NTS and PGCl than after hyperoxic hypercapnia. Part of the observed labeling could be caused by stress- or cardiovascular-related sequelae of hypoxia and hypercapnia. Possible implications for the neural control of breathing are also discussed, particularly with regard to the finding that several nuclei, not belonging to the classical brainstem respiratory centres, contained labeled cells. PMID- 9368837 TI - Distribution of astroglia in glomeruli of the rat main olfactory bulb: exclusion from the sensory subcompartment of neuropil. AB - During an entire lifetime, sensory axons of regenerating olfactory receptor neurons can enter glomeruli in the olfactory bulb and establish synaptic junctions with central neurons. The role played by astrocytes in this unique permissiveness is still unclear. Glomerular astrocytes have been identified by immunocytochemistry for glial fibrillary acidic protein and S100 proteins at the light and electron microscopic levels. The latter labeling included submicroscopic lamellar and filopodial extensions of astroglial processes. Cell bodies and processes accumulate along the border between juxtaglomerular walls and glomerular neuropil. Within glomeruli, a network of astroglial processes encloses mesh-like neuropil zones devoid of astroglia. Electron microscopy confirmed the division into subcompartments of glomerular neuropil: 1) The "sensory-synaptic subcompartment" includes all sensory axon terminals and terminal dendritic branches receiving sensory input, whereas astroglia are excluded; 2) in the "central-synaptic subcompartment," astroglial processes are intermingled with other neuropil components: dendrites of relay cells and interneurons, dendrodendritic synapses, centrifugal (cholinergic and serotonergic) axons, their axodendritic synapses, and blood vessels. Unevenly distributed astroglial processes in this subcompartment are attached to vascular basal laminae, stem dendrites, and subpopulations of dendrodendritic synapses, especially those colocalized with centrifugal projections ("triadic synapses"). Astroglia-free parts of the "central" subcompartment contain segments of dendrites and subpopulations of dendrodendritic synapses. Because of the subdivision of the glomerular neuropil into portions with and without glial components, glia do not completely demarcate the border between the "sensory" and the "central" subcompartments. Interdigitation between the subcompartments varies among glomeruli and even within a single glomerulus. The mesh width of astroglial networks covaries with numerical relations between sensory and dendrodendritic synapses. This distribution pattern of astrocytes suggests that these glial cells monitor brain-derived effects on olfactory glomerular neuropil rather than olfactory input and that astroglial processes are (re-)arranged accordingly. PMID- 9368838 TI - Subcellular localization and molecular topology of the dopamine transporter in the striatum and substantia nigra. AB - Plasma membrane transporters remove neurotransmitters from the extracellular space and have been postulated to terminate synaptic activity. Their specific roles in synaptic and nonsynaptic neurotransmission at a cellular level, however, remain unclear. We have determined the subcellular location of the dopamine transporter (DAT) by immunoperoxidase and immunogold electron microscopy, using monoclonal antibodies to both the N-terminus and the second extracellular loop. The two DAT epitopes were found on opposite faces of cellular and intracellular membranes, providing confirmation of the predicted molecular topology of DAT. In the striatum, DAT was localized in the plasma membrane of axons and terminals. Double immunocytochemistry demonstrated DAT colocalization with two other markers of nigrostriatal terminals, tyrosine hydroxylase and D2 dopamine receptors. The latter was thus demonstrated to be an autoreceptor. Labeled striatal terminals formed symmetrical synapses with spines, dendrites, and perikarya. DAT was not identified within any synaptic active zones, however, even using serial section analysis. These results suggest that striatal dopamine reuptake may occur outside of synaptic specializations once dopamine diffuses from the synaptic cleft. In the substantia nigra, DAT appears to be specifically transported into dendrites, where it can be found in smooth endoplasmic reticulum, plasma membrane, and pre- and postsynaptic active zones. These localizations suggest that DAT modulates the intracellular and extracellular dopamine levels of nigral dendrites. Within the perikarya of pars compacta neurons, DAT was localized primarily to rough and smooth endoplasmic reticulum, Golgi complex, and multivesicular bodies, identifying probable sites of synthesis, modification, transport, and degradation. PMID- 9368839 TI - Organization of the projections from the pericruciate cortex to the pontomedullary reticular formation of the cat: a quantitative retrograde tracing study. AB - Dextran-amines were used as retrograde tracers to investigate the organization of cortical projections to different cytoarchitectonic regions of the pontomedullary reticular formation of the cat. Injections into the nucleus reticularis pontis oralis resulted in labelling of neurones in the proreus cortex and area 6a beta of the premotor cortex, with little labelling in the motor cortex (area 4). This labelling was predominantly ipsilateral to the injection site. In contrast, injections into the nucleus reticularis pontis caudalis (NRPc), nucleus reticularis gigantocellularis (NRGc), and nucleus reticularis magnocellularis (NRMc) resulted in bilateral labelling--primarily in areas 6a beta, 6a gamma, and in the rostromedial region of area 4--with little labelling in the proreus cortex. In general, the cortical projections to the caudal NRGc and the NRMc were larger than those to the NRPc. More than 25% of the total projections to each of the latter three reticular regions arose from the medial part of area 4. Labelling in the hindlimb regions of area 4 was largest following the NRMc injections and smallest after injections in the NRPc. The projections to the NRPc originated from more medial parts of areas 4 and 6 than did the projections to the caudal region of the NRGc. These results suggest that areas 4 and 6 may be able to differentially activate different regions of the pontomedullary reticular formation depending on the movement that is made and perhaps also on the context of that movement. PMID- 9368840 TI - Collateral projections from striatonigral neurons to substance P receptor expressing intrinsic neurons in the striatum of the rat. AB - It is well known that striatonigral neurons produce substance P (SP); however, no SP receptor (SPR) has so far been found in the substantia nigra. On the other hand, a previous study in the rat striatum indicated that SPR was expressed only in cholinergic or somatostatinergic intrinsic neurons (Kaneko et al. [1993] Brain Res. 631:297-303). Thus, it was assumed that SP produced by striatonigral neurons might be released through their intrastriatal axon collaterals to act upon intrinsic neurons in the striatum. To confirm this assumption, the distribution of axon collaterals of striatonigral neurons was examined in the striatum of the rat. The experiments were performed on brain slices by combining retrograde labeling with tetramethylrhodamine-dextran amine, electrophysiological recording, intracellular staining with biocytin, and immunocytochemistry for SPR. The distribution of axons of cholinergic striatal neurons (a group of SP-negative intrinsic striatal neurons) was also examined. It was observed that 16% of varicosities of intrastriatal axon collaterals of striatonigral neurons, as well as 6% of axonal varicosities of cholinergic neurons, were in close apposition to dendrites and cell bodies of SPR-immunoreactive striatal neurons. Since SPR immunoreactive striatal neurons constituted only 2.7% of the total population of striatal neurons (Kaneko et al. [1993] Brain Res. 631:297-303), it appeared that axonal varicosities of striatonigral neurons were preferentially apposed to SPR immunoreactive striatal neurons and that the varicosities in close apposition to SPR-immunoreactive neurons were derived more frequently from striatonigral neurons than from cholinergic interneurons. Confocal laser scanning microscopy indicated that axonal varicosities in close apposition to SPR-immunoreactive cells showed synaptophysin immunoreactivity, a marker of synaptic vesicles. In intrastriatal axons of striatonigral neurons, it was further revealed from electron microscopy that axonal varicosities in close apposition to SPR immunoreactive dendrites, at least a part of them, made synapses of the symmetric type. Striatonigral neurons might release SP preferentially around cholinergic or somatostatinergic intrinsic neurons to regulate them through SP-SPR interactions. PMID- 9368841 TI - Grid-mapped freeze-fracture analysis of gap junctions in gray and white matter of adult rat central nervous system, with evidence for a "panglial syncytium" that is not coupled to neurons. AB - In white matter regions of the brain and spinal cord of adult mammals, gap junctions previously were observed linking astrocytes to astrocytes, as well as to oligodendrocytes and ependymacytes. The resulting "functional syncytium" was proposed to modulate the ion fluxes that occur during electrical activity of the associated axons. Gap junctions also have been reported linking neurons with glia, and functional neuronal-glial coupling has been postulated. To investigate the glial syncytium and the neuron-to-glial coupling hypotheses, we used "grid mapped freeze fracture," conventional thin-section electron microscopy, and light microscope immunocytochemistry to examine and characterize neurons and glia in gray and white matter of adult rat brain and spinal cord. We have obtained quantitative evidence for the abundance and widespread distribution of gap junctions interlinking the three primary types of macroglia throughout both gray and white matter of the mammalian central nervous system (CNS), thereby extending the concept to that of a functional panglial syncytium. In contrast to previous reports, we show that of more than 400 gap junctions in which both participating cells were identified, none were between neurons and glia. Thus, neuronal coupling and glial coupling involved separate and distinct pathways. Finally, putative water channels (i.e., "square arrays") were confirmed to be abundant and in close association with gap junctions in astrocytes and ependymacytes. Because the astrocyte "intermediaries" extend cytoplasmic conduits throughout gray and white matter of brain and spinal cord, from the ependymal layer to the pia-glial limitans, and from oligodendrocytes surrounding axons to astrocyte endfeet surrounding capillaries, the proposed panglial syncytium, with its abundance of water channels and intercellular ion channels, is optimally positioned and equipped to modulate water and ion fluxes across broad regions of the CNS. PMID- 9368842 TI - A banded topography in the developing rat's olfactory epithelial surface. AB - In situ hybridization studies from various laboratories have shown that the rat's olfactory epithelium has four distinct regions in which most putative odor receptors are located. To determine whether morphological features accompany this biochemical patterning, olfactory epithelial surfaces of rat nasal endoturbinates and septa were examined with scanning electron microscopy, placing particular emphasis on endoturbinate IIb. There was some morphological patterning at embryonic day 15 (E15), but distinct regions were not yet discernible. Regionalization became distinct at E16 and E18. Posterior regions (Regions 1 and 2) had much higher receptor cell knob densities than more anterior regions closer to the respiratory epithelium (Regions 3 and 4). Supporting cell microvilli were longer in Region 1 than in Region 2. Apices of cells surrounding the receptor cells were flatter in Regions 1 and 2 than in Regions 3 and, especially, Region 4. In Regions 1-3, these surrounding cells were made up mainly of supporting cells; in Region 4 they included respiratory cells. Regions 3 and 4 also had glandular openings and scattered microvillous cells that resemble hair cells of the ear. Older fetuses and adults showed similar evidence of patterning, but detailed examination was precluded by the increased length and entanglement of receptor cell cilia and supporting cell microvilli. In conclusion, a distinct topographic pattern, involving both receptor and surrounding cells, emerges during development of the rat olfactory epithelial surface. Location of the bands roughly matches the zones seen by in situ hybridization. PMID- 9368843 TI - Effect of permanent axotomy on number and volume of dorsal root ganglion cell bodies. AB - The effects of axotomy on the size and number of rat dorsal root ganglion cells was studied using stereological methods. Twenty adult Wistar rats were axotomized by transection of the right fifth lumbar spinal nerve approximately 7 mm distal to the fifth lumbar dorsal root ganglion (DRG-L5). The corresponding ganglia from the nonaxotomized side served as controls. The DRG-L5 were removed for study 4, 8, 15, and 45 days after axotomy. The number of neurons in each DRG-L5 was determined from estimates of the numerical density, NV, made with disectors and estimates of the volume of the ganglion using the Cavalieri principle. The mean cell body volume was determined with the vertical planar rotator method. There was a progressive loss of nerve cells during the postoperative period. There was a loss of 6% (not significant) after 4 days, 19% (not significant) after 8 days, 22% (2P < 0.05) after 15 days, and 35% (2P < 0.005) after 45 days. The relative reduction in cell number 45 days after axotomy was larger for B-cells (43%) than for A-cells (15%). The mean nerve cell body volume for the entire DRG-L5 cell population was reduced by 33% (2P < 0.005) 4 days after axotomy and remained so throughout the experimental period. The distribution of the individual cell volumes in the ganglia appeared to be uniformly shifted to lower values. It is concluded that permanent axotomy of the fifth lumbar spinal nerve results in a substantial loss of dorsal root ganglion cells and is well-suited as a model for studying the potential protective effects of neurotrophic factors using modern stereological techniques. PMID- 9368844 TI - Cortical somatosensory and trigeminal inputs to the cat superior colliculus: light and electron microscopic analyses. AB - Two different axonal transport tracers were used in single animals to test the hypothesis that the expansive intermediate gray layer of the cat superior colliculus (stratum griseum intermediale, SGI) is composed of sensorimotor domains. The results show that two sensory pathways, the trigeminotectal and the corticotectal arising from the fourth somatosensory area, commingle in patches across the middle tier of the SGI. Furthermore, the data reveal that tectospinal cells are distributed within these patches. Taken together, these results show a commingling of functionally related afferents and a consistent spatial relationship between these afferents and tectospinal neurons. These relationships indicate that the SGI consists of domains that can be distinguished by their unique combinations of afferent and efferent connections. The ultrastructural characteristics and synaptic relationships of these somatosensory afferent pathways suggest that they have distinct roles within the sensorimotor domain of the SGI. The trigeminotectal terminals are relatively small, contain round vesicles and make asymmetrical synapses on small, presumably distal, dendrites. We submit that these trigeminal terminals bestow the basic receptive field properties upon SGI neurons. In contrast, the somatosensory corticotectal terminals are relatively large, contain round vesicles, make asymmetrical synapses, participate in triads, and are presynaptic to proximal dendrites. We suggest that these cortical terminals bestow integrative abilities on SGI neurons. PMID- 9368845 TI - Parameters of transplant-mediated pupilloconstriction in rats with unilateral olivary pretectal lesions. AB - Embryonic retina, transplanted to the midbrain of neonatal rats, innervates the host brain and mediates a pupilloconstrictor response in the host eye. We hypothesise that there is a dynamic interaction between normal host and transplant photic input to the pupilloconstrictor centres. This study aims to characterise the nature of these interactions and determine the impact of experimental lesions on this reflex system. Pupillary diameter in normal rats is regulated by integration of intensity levels of the light delivered to the two eyes. The integration occurs at the primary input nucleus, the olivary pretectal nucleus, and at the output nucleus, the Edinger-Westphal nucleus. We have examined the pattern of integration of inputs delivered through the host eye and a retinal transplant placed over the midbrain at birth. Restriction of the site of integration to one olivary pretectal nucleus by ablating the contralateral nucleus causes a substantial enhancement of the transplant-mediated response and a major reduction in the host eye-mediated response. Although the pattern of change is quite similar to that seen between the two eyes of a normal animal after a similar lesion, the magnitude of improvement of the transplant response is much greater. The integration that occurs between transplant and host inputs is dynamic, and the efficacy of the transplant can be modulated by the competing host input. These results have implications for the use of neural transplants in degenerative diseases and might also offer insight into the limited functional recovery that occurs after neurological injury. PMID- 9368846 TI - Immunocytochemical localization of somatostatin and autoradiographic distribution of somatostatin binding sites in the brain of the African lungfish, Protopterus annectens. AB - The anatomical distribution of somatostatin-immunoreactive structures and the autoradiographic localization of somatostatin binding sites were investigated in the brain of the African lungfish, Protopterus annectens. In general, there was a good correlation between the distribution of somatostatin-immunoreactive elements and the location of somatostatin binding sites in several areas of the brain, particularly in the anterior olfactory nucleus, the rostral part of the dorsal pallium, the medial subpallium, the anterior preoptic area, the tectum, and the tegmentum of the mesencephalon. However, mismatching was found in the mid-caudal dorsal pallium, the reticular formation, and the cerebellum, which contained moderate to high concentrations of binding sites and very low densities of immunoreactive fibers. In contrast, the caudal hypothalamus and the neural lobe of the pituitary exhibited low concentrations of binding sites and a high to moderate density of somatostatin-immunoreactive fibers. The present results provide the first localization of somatostatin in the brain of a dipnoan and the first anatomical distribution of somatostatin binding sites in the brain of a fish. The location of somatostatin-immunoreactive elements in the brain of P. annectens is consistent with that reported in anuran amphibians, suggesting that the general organization of the somatostatin peptidergic systems occurred in a common ancestor of dipnoans and tetrapods. The anatomical distribution of somatostatin-immunoreactive elements and somatostatin binding sites suggests that somatostatin acts as a hypophysiotropic neurohormone as well as a neurotransmitter and/or neuromodulator in the lungfish brain. PMID- 9368848 TI - Comparison of the cortical connections of areas 4 gamma and 4 delta in the cat cerebral cortex. AB - Area 4 of the cat cerebral cortex has been subdivided into several regions based on cytoarchitectonic studies: areas 4 gamma, 4 delta, 4sfu, and 4fu (Hassler and Muhs-Clement [1964] J. Hirnforsch. 6:377-420). In a previous study, we found separate representations of contralateral limb movements in areas 4 gamma and 4 delta (Ghosh [1997] J. Comp. Neurol. 380:191-214). To investigate the relationship between these representations, the ipsilateral cortical connections of area 4 gamma and 4 delta were compared by the use of the retrograde neural tracers. After intracortical microstimulation of area 4, tracer was injected into one or two of the following regions: the forelimb regions of the rostral and caudal subdivisions of areas 4 gamma and 4 delta (r4 gamma, r4 delta, c4 gamma, c4 delta, separated by the cruciate sulcus) and the hindlimb regions of c4 gamma and c4 delta. Retrogradely labeled neural profiles were counted in every fourth section of the coronal series and located in cytoarchitectonic areas of the ipsilateral cortex. We found topographically organized reciprocal connections between areas 4 gamma and 4 delta; these connections were part of a rich network of interconnections between the cytoarchitectonic subdivisions of area 4. The forelimb regions of c4 gamma and c4 delta, of r4 gamma and c4 delta, and of r4 gamma and r4 delta were interconnected. These findings support the location of a secondary motor area in 4 delta. No interconnections between the forelimb regions of r4 gamma and c4 gamma, and of r4 delta and c4 gamma, could be found. Area 6 (particularly area 6a gamma) was found to project strongly to the forelimb regions of r4 gamma and r4 delta and relatively weakly to the forelimb region of c4 delta. Retrogradely labeled neurons were also detected in areas 3a, 3b, 1, 2pri, 5, 7, and insula after tracer injections in area 4. PMID- 9368847 TI - Cytoarchitecture of sensorimotor areas in the cat cerebral cortex. AB - The organization of multiple motor areas in the cerebral cortex has been investigated frequently in primates but rarely in nonprimate species. To compare sensorimotor areas in cats and primates, the cytoarchitecture of frontal and parietal areas of the cat cerebral cortex was described and mapped from coronal sections stained with cresyl violet or thionine. Multiple subdivisions of areas 4 and 6 were recognized; of these, the cytoarchitecture of area 4 gamma is similar to that of area 4 described in other carnivores and in primates and is characterized by giant pyramidal cells in multiple rows or clusters in lamina V. In other subdivisions of area 4 (4 delta, 4sfu, and 4fu), giant pyramidal cells are few or absent in lamina V, and these subdivisions resemble area 6 of primates. Area 6 of the cat cortex is heterogeneous, and differences in laminar appearance and size of pyramidal cells in lamina V distinguish its four subdivisions (6a alpha, 6a beta, 6a gamma, and 6iffu). The adjoining prefrontal areas are distinguishable from area 6 by the presence of a thin internal granular lamina (lamina IV) and the reduced size of pyramidal cells in lamina V. Laminae are poorly differentiated in the cingulate areas, where a rostral and caudal subdivision can be distinguished on the basis of the absence or presence of lamina IV. Area 3a is characterized by a thin lamina IV and is located between frontal agranular and parietal granular (well-defined lamina IV) fields (3b, 1, 2, 2pri, 5, and 7). Insular cortex can be subdivided into granular and agranular fields. PMID- 9368849 TI - Ipsilateral cortical connections of area 6 in the cat cerebral cortex. AB - Many motor areas have been identified within cytoarchitectonic area 6 of the cerebral cortex in primates. To provide a better understanding of the motor functions of area 6 in the cat, the ipsilateral cortical connections of the different cytoarchitectonic subdivisions of area 6 (areas 6a alpha, 6a beta, 6a gamma, and 6iffu) were studied by the use of fluorescent retrograde tracers. Tracer injections, made in the forelimb and face regions of areas 6a alpha and 6a gamma, were guided by data from intracortical microstimulation (ICMS). ICMS did not evoke movements from areas 6a beta and 6iffu. Retrogradely labeled neurons were enumerated in cytoarchitectonically identified areas in the frontal and parietal lobes to show that the subdivisions of area 6 are strongly interconnected except for areas 6a gamma and 6a beta. There are considerable differences in the pattern of connections of the area 6 subdivisions with area 4 and with prefrontal, cingulate, and parietal cortices. Area 4 gamma projects strongly to area 6a gamma but not to the other subdivisions. Areas 4 delta, 4fu, and 4sfu project strongly to 6a alpha and 6iffu but relatively weakly to area 6a beta. Prefrontal areas project strongly to area 6a beta and 6iffu, moderately to 6a alpha, but weakly to area 6a gamma. Cingulate areas project strongly to area 6iffu and moderately to areas 6a alpha and 6a beta but do not project to area 6a gamma. Parietal projections from primary and second somatosensory cortex were directed to area 6a gamma, whereas areas 5, 7, and insula were found to project to all the subdivisions of area 6. These findings support earlier suggestions that secondary motor areas may be located in areas 6a alpha and 6a gamma (Ghosh [1997] J. Comp. Neurol. 380:191-214). Features of the pattern of cortical connections of area 6 common to the cat and primates suggest that their motor areas in the frontal lobe are organized in a similar manner. PMID- 9368850 TI - Immunohistochemical identification of discrete subsets of rat olfactory neurons and the glomeruli that they innervate. AB - Glomeruli at the posterior margin of the main olfactory bulb differ in several respects from those located in the remainder of the bulb; e.g., the olfactory sensory neurons (OSNs) that project here exhibit a distinct biochemical phenotype and signal transduction pathway, the microcircuitry of the glomeruli is substantially altered, and the glomeruli are activated by unconventional odorants. In the present work, we report that the monoclonal antibodies 2C6 and MAb213 label distinct subsets of OSNs in the olfactory epithelium (OE), including their axons to their terminations in the main olfactory bulb (MOB). Neurons immunopositive with 2C6 are concentrated in the cul-de-sacs of ectoturbinates 1 and 2 and of endoturbinate IV. Unlike the vast majority of OSNs, 2C6(+) neurons express olfactory marker protein (OMP) at a low level, but their failure to stain with anti-GAP-43 labeling indicates that the OMP "weak" neurons are nonetheless mature. Glomeruli positive for 2C6 are bilaterally symmetrical and occupy reproducible positions along the posterior margin of the MOB. Three of these are very large, and we refer to them as the lateral, posterior ventral, and anterior ventral 2C6(+) necklace glomeruli. MAb213(+) neurons are concentrated in the posteriormost tips of the cul-de-sacs and recesses at the reflection of the OE at the cribriform plate. Like 2C6(+) neurons, MAb213(+) OSNs are weakly labeled with anti-OMP but are fully mature. MAb213(+) glomeruli are also bilaterally symmetrical; they occupy reproducible positions along the posterior margin of the MOB. The three largest glomeruli occupy lateral, posterior ventral, and posterior positions; the first two are found close to the aforementioned 2C6(+) glomeruli. MAb213 also intensely labels one of the glomeruli of the modified glomerular complex, a string of small glomeruli ventrally, and another string dorsal to the accessory olfactory bulb. Acetylcholinesterase (AChE) histochemical staining of adjacent sections showed that many, but not all, MAb213(+) glomeruli colocalize with dense or moderate AChE staining. Thus, it is likely that the "necklace olfactory glomeruli" (Shinoda et al., 1990, 1993) and the phosphodiesterase (PDE2)(+) glomeruli (Juilfs et al., 1997) are a subset(s) of the MAb213(+) glomeruli. On the other hand, 2C6(+) glomeruli are not associated with AChE staining. These data indicate that the 2C6(+) glomeruli comprise a novel subset in the posterior MOB. In addition to the 2C6(+) and MAb213(+) necklace glomeruli, there is another distinct set of glomeruli at the posterior margin of the bulb that are OMP(-), 2C6(-), and MAb213(-). In summary, the current work indicates that glomeruli at the posterior margin of the bulb, which are necklace glomeruli in terms of location and appearance, are actually heterogeneous and may subserve specialized functions within the olfactory system. PMID- 9368851 TI - Cell movement and cell cycle dynamics in the retina of the adult teleost Haplochromis burtoni. AB - The authors analyzed the pattern of neurogenesis, the time frame of cell movement, and the cell cycle kinetics of a population of stem cells located in the outer nuclear layer in the retina of the adult teleost Haplochromis burtoni. These stem cells continue to give rise to new rod photoreceptors throughout life. The new rods move vitread after the last cell division. The authors investigated events during cell division and cell differentiation by using one marker that labels dividing cells transiently (proliferating cell nuclear antigen) along with another marker that labels dividing cells permanently (bromodeoxyuridine). The bulk of cell movement does not occur within 24 hours after S-phase labeling but is clearly underway 12 hours later, shortly after mitosis. The cell cycle length was estimated to be approximately 25 hours. The distribution of labeled cells at various times after S-phase suggests that new rods are generated by asymmetric cell division, that is, one of the daughter cells moves after mitosis and becomes postmitotic, while the other daughter cell remains in place and reenters the cell cycle. The proliferation patterns across the retina suggest that the location of areas of mitotic activity changes over time. The authors hypothesize that local extracellular factors control the rate of cell division in a given area, thereby keeping the overall rod density constant. PMID- 9368852 TI - Associations between neuropeptide Y nerve terminals and intraparenchymal microvessels in rat and human cerebral cortex. AB - Neuropeptide Y (NPY) can influence local brain perfusion, possibly via direct relationships with the microvascular bed. To evaluate this possibility, the authors quantitatively analyzed by light and electron microscopy the morphological associations between immunostained NPY neuronal elements and intraparenchymal microvessels in the rat and human cerebral cortex. At the light microscopic level in the rat frontoparietal cortex, about 16% of NPY neurons and large proximal processes as well as a subset of nerve terminals not affected by double sympathectomy were associated with penetrating arterioles and local microvessels. In human temporal cortex, a dense network of NPY nerve fibers was observed, many of which approached and/or contacted intracortical vessels. At the ultrastructural level, 14% of NPY axonal varicosities in the rat cerebral cortex were considered perivascular and associated with capillaries (approximately 70%) or microarterioles (approximately 30%). They were particularly enriched in the immediate vicinity (< 0.25 micron) of the microvessels, where the perivascular astrocytic leaflets represented a frequent target. In human cerebral cortex, NPY varicosities were observed in proximity to microvessels corresponding primarily to capillaries. Perivascular NPY varicosities never established synaptic junctions with vascular or astroglial elements. The results show that central NPY nerve terminals associate with microvessels and perivascular astroglial cells in the rat and human cerebral cortex. Thus, NPY released from these nerves could possibly influence (via a parasynaptic mode of action) vascular and/or astrocytic functions depending on the distribution of NPY receptors in these cellular compartments. These results provide morphological support for the effects of NPY on brain perfusion and homeostasis. PMID- 9368853 TI - Target- as well as source-derived factors direct the morphogenesis of anomalous retino-thalamic projections. AB - Neonatal tectal lesions in hamsters result in the elimination of a major central target of retinal axons, massively denervate the lateral posterior nucleus of the thalamus (LP), and lead to a marked increase of the retino-LP projection. In such animals, retino-LP axons show all of the normally-occurring terminal types. In addition, large clusters of varicosities, whose tubular configuration resembles the major type of tecto-LP terminals observed in normal animals, are also noted if the tectal lesion is made on the day after birth (P1). If, however, the neonatal lesion occurs on P5 rather than on P1, terminals resembling normal tecto LP endings are rarely observed; rather, the distribution and morphology of retino LP terminals bear a greater resemblance to those seen in normal hamsters, but the size and complexity of the terminals, particularly those that form string-like arrangements, is significantly increased. Our findings suggest that the altered morphology of some abnormally induced retino-LP terminals may be orchestrated by target-associated signals. However, there are age-related limitations on the degree to which afferent systems can vary their terminal morphology; these restrictions may derive from the target, or may be a function of intrinsic changes within the cells of origin of the afferent fibers. PMID- 9368854 TI - Afferents from the colliculus, cortex, and retina have distinct terminal morphologies in the lateral posterior thalamic nucleus. AB - We have examined the morphology of afferent endings that originate in three distinct cell groups and terminate in the lateral posterior nucleus of the thalamus (LP). Retino-LP projections were sparse, occurred throughout the nucleus, and could be classified into 1) simple en passant varicosities and terminal swellings found on poorly branched fibers in all LP subdivisions, 2) string-like configurations of varicosities detected largely in the medial subdivision of the LP, and 3) terminals resembling retinogeniculate endings occurring mainly in the rostral part of the superficial subdivision of the LP adjacent to the dorsal nucleus of the lateral geniculate body. Cortico-LP terminals fell into three classes: 1) single varicosities decorating the tips of short appendages on fine preterminal and terminal axons; 2) tiny, round varicosities studding the axon shaft; and 3) boutons of variable shape visible on medium-caliber corticothalamic fibers. Tecto-LP terminals exhibited a large variation in morphology and density. Those found most commonly could be classified into two groups: 1) individual swellings and 2) terminal clusters arranged in a tubular configuration that enclosed a central channel, most likely occupied by the dendrite of a postsynaptic neuron. An unusual tecto-LP terminal consisted of an ovoid swelling (up to 20 microns in the long axis) from which emerged several long, thin extensions and was seen at the tips of large-diameter axons. These results show that, despite having overlapping projection zones, each set of afferents that projects to the LP elaborates terminal specializations that are structurally distinct from others projecting to the same target area. PMID- 9368855 TI - Glial cell line-derived neurotrophic factor prevents death, but not reductions in tyrosine hydroxylase, of injured nigrostriatal neurons in adult rats. AB - Glial cell line-derived neurotrophic factor (GDNF) promotes survival of mesencephalic dopaminergic neurons in vitro and when injected locally into the brains of lesioned adult animals. Here, we show that GDNF (3 micrograms per day and higher) can promote the survival of all (retrogradely labeled) axotomized nigrostriatal dopaminergic neurons of adult rats when continuously infused for 2 weeks close to the substantia nigra, compared to only approximately 30% survival with control infusions. Based on our previous observations, GDNF was as potent as ciliary neurotrophic factor and neurotrophin-4 and approximately five to ten times more potent than brain-derived neurotrophic factor and was most effective in promoting survival. GDNF prevented neuronal death induced by 6-hydroxydopamine to a lesser extent than after axotomy. GDNF treatments begun 1 week after axotomy could maintain those neurons that had not yet died. When a 2 week GDNF treatment was interrupted, most of the GDNF-rescued neurons died over the following 2 weeks. This suggests that longer trophic factor treatments or nigrostriatal connections are needed to achieve permanent survival. Measurements of tyrosine hydroxylase (TH) immunoreactivity of the rescued neuronal cell bodies suggest that GDNF cannot prevent the lesion-induced loss of this rate-limiting enzyme for dopamine synthesis. In fact, GDNF induced a decrease in TH in normal animals, suggesting an active down-regulation of TH synthesis. Levels of TH immunoreactivity were recovered between 7 and 14 days after withdrawal of a 2 week GDNF infusion, in the neurons that survived axotomy. These results may have implications for developing new treatment strategies for Parkinson's disease. PMID- 9368857 TI - Results of a modified staircase technique for reconstruction of the lower lip. AB - Our experience with a modified staircase technique for closure of lower lip defects is reported. The procedure is based on the original technique of Johanson et al. (1974). However, the integrity of the orbicularis oris muscle is respected when advancing lower lip flaps. Twenty patients with squamous cell carcinoma of the lower lip were treated using this modified reconstruction technique. The size of the defects ranged from 30-60% of lower lip width. No recurrences were observed during a 3-year to 5-year follow-up. All patients showed symmetrical lip movement, an adequate buccal sulcus and intact labial commissures. No symptomatic microstomia was seen and the aesthetic results were excellent. The surgical technique is explained in detail. Four types of flap are presented according to the size and location of lip defects. Lower lip defects up to 60% of the lip width can be closed easily, with good aesthetic results. The technique is also applicable to upper lip reconstruction. PMID- 9368856 TI - Vsx-1 and Vsx-2: differential expression of two paired-like homeobox genes during zebrafish and goldfish retinogenesis. AB - Vsx-1 and Vsx-2 are two homeobox genes that were cloned originally from an adult goldfish retinal library. They are members of the paired-like:CVC gene family, which is characterized by the presence of a paired homeodomain and an additional conserved region, termed the CVC domain. To analyze the possible roles for Vsx-1 and Vsx-2 in eye development, we used in situ hybridization to examine their expression patterns in zebrafish and goldfish embryos. Vsx-2 is initially expressed by proliferating neuroepithelial cells of the presumptive neural retina, then it is down-regulated as differentiation begins, and it is finally reexpressed at later stages of differentiation in a subset of cells, presumed to be bipolar cells, in the inner nuclear layer. In contrast, Vsx-1 is expressed only weakly in undifferentiated, presumptive neural retina and is then up regulated selectively in presumptive bipolar cells at early stages of differentiation (when Vsx-2 is turned off), before decreasing to an intermediate level, which is maintained in the differentiated (adult) retina. The restricted expression patterns of Vsx-2 correspond to the observed phenotypes in mice with the ocular retardation mutation (orJ), further supporting the notion that Vsx-2 and Chx10 are homologues. The sequential complimentary and then corresponding expression patterns of Vsx-1 and Vsx-2 suggest that these similar transcription factors may be recruited for partially overlapping, but distinct, functions during the development of the retina. PMID- 9368858 TI - Comparative study of the ipsilateral full thickness forearm skin graft in closure of radial forearm flap donor site defects. AB - The early experience of our unit with the technique of ipsilateral full thickness forearm skin grafting of the radial forearm flap donor site defect is described. The technique provides the advantages of a full thickness skin graft whilst avoiding the need to harvest skin from a remote area. We have compared the results with that of split skin grafts used contemporaneously for the same purpose in our unit; the advantages and disadvantages are outlined. Continued success has encouraged us to utilize this technique routinely with certain modifications which we describe. PMID- 9368859 TI - Profiloplasty: variations in personal views. AB - There is sometimes controversy among colleagues over treatment plans in orthognathic surgery. This is because there are differing ideas about which part of the facial skeleton should be moved to give an optimal result. A study was therefore set up to obtain insight into the differences between surgeons. Ten unbalanced profile drawings were given to seven experienced surgeons with the request that they draw the profile line which they would like to give these patients. It was acceptable either to draw the profiles 'artistically' off the cuff or to use additional construction lines as long as this was not the profile planning according to Brons and Mulie (1993). The evaluation showed that some surgeons drew profiles which resembled each other to some extent in proportions and inclinations, while others produced variations without any evident regularity and basic concept. The variability per profile was very important in almost all cases. Such discrepancies are not acceptable in a teaching centre. PMID- 9368860 TI - Correction of maxillofacial asymmetry using orthognathic surgical methods. AB - A total of 20 patients with varying degrees of facial asymmetry were followed clinically and radiographically for at least 18 months after undergoing surgical correction. In 12 of the patients, the cause of asymmetry was hemifacial microsomia of varying severity. Infection of the TMJ in early childhood and irradiation damage were other causes of facial growth disturbance. Bimaxillary osteotomy was carried out in all cases and was often combined with resection of the coronoid process in order to lengthen the ramus. A postoperative jaw exercise programme has proved important as a means of maintaining or increasing mouth opening capacity. The facial asymmetry cases are not easy to correct and are not always in line with expectations. However, they are an important part of maxillofacial reconstructive surgery. PMID- 9368862 TI - Analysis of primary gingivoperiosteoplasty in alveolar cleft repair. Part I: Facial growth. AB - The primary gingivoperiosteoplasty by Millard consists of presurgical active orthognathic treatment ('Latham device') of the alveolar margins at the age of 3 months and of surgical closure of the alveolar cleft with local gingivoperiosteal flaps at the age of 5 months. The aim of this investigation was to analyse the facial growth following this treatment. The following material was studied: lateral head X-rays and plaster casts from 146 patients with unilateral (UCLP) and bilateral (BCLP) clefts of lip and palate from birth to 16 years of age. Ninety-one of these patients formed the control group, who received neither gingivoperiosteoplasty nor pre-surgical active orthognathic treatment. The same surgeon and orthodontist treated all 146 patients. A three-dimensional growth disturbance after gingivoperiosteoplasty was observed: 42% patients with UCLP and 40% patients with BCLP had an 'open bite' following closure of the alveolar cleft (control group 5%/10%). The length of the upper jaw in patients who underwent gingivoperiosteoplasty was shorter than in the control group. The frequency of posterior cross bite was also higher in the gingivoperiosteoplasty group. These results demonstrate that treatment with a 'Latham device' disturbs facial growth. Therefore, this treatment should be abandoned. PMID- 9368861 TI - Maxillary sinus septa: incidence, morphology and clinical implications. AB - This study was carried out to examine the incidence, morphology and clinical implication of antral septa. Out of 265 maxillary sinuses, 65 sinuses in atrophic maxillae were examined clinically during sinus floor elevation and 200 sinuses examined radiographically (CT), the latter being further subdivided into non atrophic/dentate and atrophic/edentulous maxillary segments. Eighteen (27.7%) out of 65 clinically-examined maxillae and 32 (16%) out of the 200 non-preselected CT examined maxillary sinuses showed antral septa. CT-topogram subclassification revealed 21 septa (13.2%) in 159 non-atrophic and 11 septa (26.8%) in 41 atrophic maxillary segments (P < 0.01). Morphologically, CT examination yielded one complete septum (0.5%), 21 incomplete septa on the sinus floor and 10 incomplete septa on the anterior antral wall (5%). CT revealed a significantly greater dimension of antral septa in non-atrophic maxillary segments than in atrophic ones (P < 0.01). In atrophic maxillary sinuses, the incidence (27.7% vs 26.8%), morphology (all septa located on sinus floor) and height (8.1 +/- 2.5 mm vs 6.8 +/- 1.6 mm) did not differ between the clinical and the CT examinations. Detailed knowledge about location, morphology and height of antral septa is clinically relevant to reduce the rate of complications when maxillary sinus surgery, i.e. sinus floor elevation, is carried out. PMID- 9368863 TI - Nasal airway in cleft-palate patients: acoustic rhinometric data. AB - The objective of this study was to investigate an instrumental assessment technique for acquiring reproducible, metric data on the nasal airway in cleft palate associated nasal dysplasia. A consecutive sample of 23 unilateral, 17 bilateral CLP patients and 15 controls with subjective normal nasal patency from a cleft-palate rehabilitation centre were studied. A series of transnasal acoustic measurements (pressure wave: 55 dB for 2 ms) of nasal volume were performed before and after topical decongestion with 2 x 0.3 mg of xylometazoline. A standardized regimen of acoustic parameters of the nasal valve and the adjacent segment of the nasal cavity were calculated. The cleft side yielded a significantly (40%) lower nasal volume than the non-cleft side. Considerably lower values were recorded for the isthmus of the cleft side (0.31 cm2) compared with the non-cleft side (0.52 cm2). Decongestion capacity was higher in the posterior segment, indicating cleft-side massive mucosal hypertrophy. In bilateral CLP, the isthmus measured 0.46 cm2. By decongestion, individual side differences were reduced in unilateral CLP patients but enhanced in bilateral clefts. The prevailing pattern of the cleft-side airway profile can be described as a 'descending W'. Acoustic rhinometry is a non-invasive, instrumental assessment technique for acquiring reproducible metric data of nasal dysplasia in cleft-palate patients. By identification of the location and amount of nasal obstruction, it provides topographic information about the individual airway profile. It is suitable for the longitudinal investigation of nasal-airway development, as well as the preparation and follow-up of corrective rhinosurgery. PMID- 9368864 TI - Rigid internal fixation of the jaws in an adult patient with facio-scapulo humeral muscular dystrophy: report of a case. AB - This study shows the advantages of rigid internal fixation in the surgical management of a facial deformity in a 29-year-old patient with facio-scapulo humeral dystrophy (FSHD). After presurgical orthodontic treatment, surgery consisted of a Le Fort I maxillary osteotomy, with 5 mm of anterior movement, and fixation with miniplates. After mandibular sagittal split set-back osteotomy, internal fixation was applied on each side using two bicortical screws; no postoperative intermaxillary fixation was utilized. At the 2-year follow-up, the patient was satisfied with the surgical results; lip competence and occlusion were good. The advantages of using internal rigid fixation are: immediate osseous stability which does not require intermaxillary fixation, improved perioperative airway management (no preoperative tracheostomy) and earlier functional recovery. PMID- 9368866 TI - Screening for neuroblastoma in children. PMID- 9368865 TI - Unusual penetrating faciocranial injury caused by a knife: a case report. AB - Penetrating head and neck trauma in children is uncommon and are potentially life threatening injuries. Penetrating trauma to the head in children is a challenging problem for both the initial evaluating physicians and surgeons. We report upon a patient who had fallen from a tree while cutting vegetables and sustained a penetrating faciocranial injury caused by his knife. Clinical examination showed a knife which had entered his face in the right preauricular, pre temporomandibular joint area below the zygomatic arch. His left bulbus oculi was exophthalmic and a complete ptosis was present. He was fully conscious. The only abnormal finding was complete left visual loss. The other neurological ophthalmological and systemic physical evaluations were normal. The Glasgow Coma scale score was 14. The modalities of treatment and the outcome of the operation are described and the management of similar injuries is discussed. PMID- 9368867 TI - An appraisal of the efficacy and cost effectiveness of antenatal screening for hepatitis B. AB - In this review published data are used to determine the benefits and costs of antenatal screening for hepatitis B carriers to prevent the later occurrence of hepatoma and chronic liver disease in their offspring. In Britain, babies born to carrier mothers have a 25% risk of perinatal infection and of becoming carriers themselves (the risk is 82% if their mothers are positive for the e antigen and 10% if negative). The carrier state increases the risk of hepatoma an estimated 86 times and the risk of chronic liver disease 20 times. Life table analysis showed that there is an 11% lifetime risk in carriers in Britain of dying from hepatoma (which results in seven years of life lost on average) and a 7% risk of chronic liver disease (14 years of life lost). Neonatal vaccination reduces the risk of the infant becoming a carrier by about 90%. Perinatal transmission occurs in 38 of every 100,000 neonates in Britain. Antenatal screening of all women and vaccinating babies of carrier mothers would prevent perinatal transmission in 34 of the 38 children (90%), or 255 per year in Britain. Of these 34, 8.4 children would be Chinese in ethnic origin, 4.2 African, 11.5 South Asian (from the Indian subcontinent), 2.0 Caribbean, and 7.3 would be white. Six deaths in the 34 from hepatoma or chronic liver disease caused by hepatitis B would then be prevented. The direct cost in Britain of screening all women, irrespective of ethnicity, at their first pregnancy only, would be 1300 pounds for each year of life saved (undiscounted) or 2500 pounds if screening at every pregnancy. Screening just Chinese, Africans, and South Asians, at first pregnancy only, would cost 330 pounds for each year of life saved but would prevent only 64% of these deaths. Vaccinating the infants of carrier mothers is likely also to prevent horizontal transmission of hepatitis B in early childhood and prevent the carrier state developing in an estimated three extra children for each child protected from vertical transmission. When this is taken into account the number of deaths prevented increases fourfold, reducing the cost for each year of life saved by 75%. Screening all women at first pregnancy only is an acceptably cost effective policy in Britain (1300 pounds for each year of life saved), actually preventing 45 deaths a year from hepatoma and chronic liver disease (or about 180 deaths if those horizontally infected are included), at a total cost of 540,000 pounds a year. It has the advantage of being comprehensive, equitable, and easier to implement than a policy based on screening of high risk ethnic groups. PMID- 9368868 TI - Adverse effects of screening for gestational diabetes: a prospective cohort study in Toronto, Canada. AB - OBJECTIVE: To investigate the adverse effects associated with a false positive 50 g glucose challenge test for gestational diabetes mellitus (GDM). SETTING: Consecutive women attending a prenatal registration clinic at a large community hospital in suburban Toronto, Canada. METHODS: Prospective cohort study of women between 12 and 24 weeks' gestation with no previous history of diabetes mellitus or GDM. Main outcome measures included anxiety (Spielberger's State-Trait Anxiety Inventory), depression (Centers for Epidemiologic Studies Depression Scale), perceived maternal health, and concern about health of the newborn. RESULTS: Among 2564 eligible subjects, there were 897 subjects with complete data at enrollment and at 32 weeks' gestation, including 88 who had false positive glucose challenge test results. At 32 weeks, only 20% (95% confidence limits 11%, 28%) of women with false positive glucose challenge test results rated their health as excellent, compared with 38% (35%, 42%) of those having negative results and those not tested (P = 0.001). These results were sustained at 36 weeks. There was no association between glucose challenge test result and the change in anxiety (P = 0.57), depression (P = 0.09) or concern about health of the newborn (P = 0.91) between baseline and 32 weeks' gestation, nor were these associations found at 36 weeks. CONCLUSIONS: False positive glucose challenge test results are about six times more likely than true positive results in the general population. Pregnant women with false positive GDM screening results experience a significant decline in their perception of their own health. These adverse effects should be taken into account when deciding about a policy of screening all pregnant women for gestational diabetes. PMID- 9368869 TI - Heterozygosity for Tay-Sachs and Sandhoff diseases among Massachusetts residents with French Canadian background. AB - OBJECTIVES: The frequency of Tay-Sachs disease (TSD) heterozygosity is increased among French Canadians in eastern Quebec. A large proportion of the New England population has French Canadian heritage; thus, it is important to determine if they too are at increased risk for TSD heterozygosity. This prospective study was designed to assess the TSD heterozygote frequency among people with French Canadian background living in Massachusetts. A simultaneous screen for heterozygosity for Sandhoff disease, a related genetic disorder, was also undertaken. METHODS: 1260 non-pregnant subjects of French Canadian background were included in the study. beta hexosaminidase activity was measured in blood samples, and results were evaluated for TSD and Sandhoff disease heterozygosity. Samples from the TSD heterozygotes were also subjected to mutation analysis. RESULTS: Of the 1260 samples studied, 22 (1 in 57; CI 1 in 41, 1 in 98) were identified as TSD heterozygotes by enzymatic analyses and 11 subjects (1 in 114; CI 1 in 72, 1 in 280) were identified as Sandhoff disease heterozygotes. Three of the 22 TSD heterozygotes were found to have benign pseudodeficiency mutations, resulting in a maximum TSD heterozygote frequency of 19 in 1260 (1 in 66; CI 1 in 46, 1 in 120). Together, these data provide a maximum frequency of heterozygosity for TSD or Sandhoff disease of 30 in 1260 (1 in 42; CI 1 in 31, 1 in 64) in this population. CONCLUSIONS: Simultaneous screening for TSD and Sandhoff disease heterozygosity by assay of beta hexosaminidases A and B activities provides a possible method for use with subjects of French Canadian background. The relevance of some of the novel mutations identified in this group needs further study. However, the comparatively high combined frequency of TSD and Sandhoff disease heterozygosity indicates a need for discussion regarding the appropriateness of carrier testing for these disorders for persons of French Canadian background in Massachusetts. PMID- 9368870 TI - Evaluation of surveillance programmes for colorectal cancer in ulcerative colitis patients by case-control studies: methodological considerations. AB - OBJECTIVES: The evaluation of the efficacy of colonoscopy screening in patients with ulcerative colitis for colorectal cancer is associated with methodological difficulties. Case-control studies can, however, be used to determine the efficacy of such a programme and the outline of the methodology in such a programme is presented. METHODS: The randomised controlled trial provides perspective for case-control studies of screening efficacy. Cases are selected from persons who have ulcerative colitis with manifestations of colorectal cancer: for example, those who have died of colorectal cancer or have symptomatic metastases. Controls are selected from persons who have ulcerative colitis, who had been alive when the case died of colorectal cancer, and who had been subject to the risk of dying from, but had not had, colorectal cancer diagnosed when the case was diagnosed with colorectal cancer. The relevant screening history for cases begins with the case's diagnosis of ulcerative colitis and ends with the cases diagnosis of colorectal cancer; that for controls should be comparable to that for cases to avoid bias. Cases and controls are compared with respect to their "exposure" to colonoscopy during their screening histories: the occurrence of any screening, which took place during the period of time that an occult tumour (or an identifiable lesion) may plausibly have been present. CONCLUSION: The proposed methodology can evaluate the efficacy of a screening programme rapidly, practically, and ethically. PMID- 9368871 TI - Cost analysis in a population based screening programme for colorectal cancer: comparison of immunochemical and guaiac faecal occult blood testing. AB - OBJECTIVE: To compare the costs of colorectal cancer (CRC) screening by two faecal occult blood tests (FOBT)-namely, Hemoccult (guaiac based) and reversed passive haemagglutination (RPHA) tests. RPHA was interpreted according to two positivity thresholds (+ or +/-). METHODS: Attenders performed both tests. Subjects with a positive FOBT test were invited to have a complete exploration of the colon. The total costs for every 10,000 screened subjects and costs for each unit of result (screened subject, or patient with adenoma/s or cancer detected) were calculated for both tests. RESULTS: 8353 subjects were enrolled. A total of 2109 repeated screening after two years. RPHA(+ and +/-) showed the highest and RPHA(+) the lowest positivity rate at first screening. The Hemoccult positivity rate was highest at repeat screening. Total costs of screening by RPHA(+ and +/-) were highest as this method had the highest recall rate. Screening by RPHA(+) was the least costly. Costs for each screened subject were highest for RPHA(+ and +/ ) and lowest for RPHA(+). Costs for each cancer detected were lowest for RPHA(+) and highest for Hemoccult or RPHA(+ and +/-) in subjects aged > 49 or < 50, respectively. Costs for subjects with detected adenoma/s of > 9 mm were lowest for RPHA(+ and +/-) and highest for Hemoccult. At repeat screening total costs of RPHA(+ and +/-) were lower than at first screening, whereas for each subject with cancer or adenoma/s costs were increased. CONCLUSIONS: Our data confirm that screening by RPHA is more cost effective than by Hemoccult. PMID- 9368872 TI - Participation in faecal occult blood screening for colorectal cancer in a well defined French population: results of five screening rounds from 1988 to 1996. AB - OBJECTIVE: To evaluate the influence on compliance of demographic variables and of the way of proposing a faecal occult blood test in a colorectal cancer mass screening programme. SETTING: Well defined population in Burgundy (France). METHODS: From 1988 to 1996 five screening rounds were conducted in people aged 45 to 74 on entering the study. The screening test was provided free of charge by primary care physicians over a four month period, then mailed to non-consultants, followed by a potential reminder letter. The whole population was invited to participate in each screening campaign. RESULTS: During the five successive rounds, compliance was 52.8%, 54.0%, 57.3%, 58.3%, and 56.2%. It was higher in women than in men, in those initially aged 50 to 69 than in the extreme age groups, and in urban than in rural areas. Overall, 68.7% of the invited population completed at least one screening test and 37.2% completed the five rounds. Among those who participated once in a screening campaign, between 79.6% and 87.6% participated in the succeeding ones. Compliance was higher when the test was proposed by GPs (varying between 85.2% and 94.0% according to the screening campaign) than when it was sent by post (varying between 26.0% and 33.7%). CONCLUSION: In France, a participation rate of over 50% can be achieved in colorectal cancer screening by means of a faecal occult blood test. To achieve this, primary care physicians have to play an active part in the programme and the test must be mailed to non-consultants. PMID- 9368873 TI - Screening status in relation to biological and chronological characteristics of breast cancers: a cross sectional survey. AB - OBJECTIVE: To determine the pathological and biological characteristics of breast cancers diagnosed by screening and examined at the Edinburgh University pathology department. METHODS: These cancers were classified by screening status: never screened (n = 111), prevalence screen detected (n = 105), and previously screened (n = 74). The last category arose in women who had been regularly screened during the trial; the cancers were diagnosed as interval cases before the first invitation to service screening (n = 33) or were incidence screen detected at that time (n = 41). RESULTS: Association (for operable invasive cancers, n = 250) of cancer characteristics with screening status reflects influences of biology (aggressiveness) or chronology (time of diagnosis), or both. The prognostic indicators tumour grade, histological type, and oestrogen receptor status were found in a smaller percentage of the patients with poor prognosis among the prevalence screen detected cases (9%, 77%, 18%) than among those previously screened (29%, 84%, 35%). The chronological factors size and node status were found in a smaller percentage of patients with poor prognosis among women previously screened (31%, 24%) than among those never screened (62%, 39%). Apart from these two, no other factors improved the diagnosis in the previously screened group compared with the never screened group. CONCLUSIONS: These results suggest that favourable characteristics of screen detected cases are often due to the effects of length bias on "biological factors" and fail to show that current local screening practice has succeeded in advancing the diagnosis of breast cancers to a less aggressive phase. PMID- 9368874 TI - Breast screening: adverse psychological consequences one month after placing women on early recall because of a diagnostic uncertainty. A multicentre study. AB - BACKGROUND: It was the original intention of the UK National Health Service Breast Screening Programme (NHSBSP) to place women who were not diagnosed with cancer on three yearly routine recall (RR). In 1994-5 approximately 16,500 women, aged 50 to 64, were placed on early recall (ER) at a shorter time interval, of which about 98% will have a normal result. This large number exceeds the expectations of the NHSBSP. OBJECTIVE: To establish the adverse psychological consequences (PCs) for women one month after placement on ER because of a diagnostic uncertainty, and if detected, to suggest practical solutions to reduce them. METHODS: Thirteen breast screening centres throughout the UK participated in the study. From March to October 1995 all women who were placed on ER because of a diagnostic uncertainty were identified and compared with groups of women placed on RR (after mammography, assessment, fine needle aspiration, and a benign biopsy). These women were invited to complete a postal questionnaire one month after they were placed on ER or RR. One reminder was sent. RESULTS: Overall 75% of women completed the questionnaire. The adverse PCs of placing women on ER because of a diagnostic uncertainty were higher (63%; n = 81 of 130) than those of women placed on RR after mammography (29%; n = 38 of 130) (P < 0.00001) or assessment (50%; n = 64 of 128) (P < 0.05), but lower than the adverse PCs of women who underwent a benign biopsy (87%; n = 26 of 30) (P < 0.05). Factors that were significantly associated with subsequent adverse PCs were identified. CONCLUSIONS: The adverse PCs of being placed on ER because of a diagnostic uncertainty were significantly higher than those of women who turned out to have a false-positive mammographic result after assessment. Possible practical solutions are discussed. PMID- 9368875 TI - Interval breast cancers in the NHS Breast Screening Programme: does the current definition exclude too many? AB - OBJECTIVES: To examine the impact of the definition of interval breast cancers on interval cancer rates arising from the prevalent (first) screening round. DESIGN: Interval breast cancers arising from the prevalent (first) screening round at the Warwickshire, Solihull and Coventry Breast Screening Unit (17 April 1989 to 31 March 1992) were identified by comparison of data held at the unit with records at the West Midlands Cancer Intelligence Unit. Exclusion criteria used in National statistics were applied to this sample to quantify their impact on achieved interval cancer rates. The round lengths experienced by individual women at the unit were determined from the prevalent and incident invitation dates for 155 women with incident (re-screen) breast cancers detected in the second round. SETTING: Warwickshire, Solihull and Coventry Breast Screening Unit. SUBJECTS: 59,017 women screened between 17 April 1989 and 31 March 1992 with a negative screening result and 155 women with incident screen detected cancers. RESULTS: A total of 278 interval cancers were identified, giving an overall rate from the prevalent screening round of 47.1/10,000 women screened. Of these, 213 met the criteria used in the definition of interval cancers for National statistics and were termed "core" interval cancers. The overall "core" interval rate was 36.1/ 10,000 women screened, similar to interval cancer rates found in the north west of United Kingdom. Thus applying commonly used exclusion criteria produced a 23.4% reduction in the apparent interval cancer rate, with the largest decrease resulting from the exclusion of cancers arising at 36 months or more from the last screen. CONCLUSIONS: The exclusion criteria used in the definition of interval cancers have a significant impact on observed interval cancer rates. Of particular concern is the exclusion in the current National definitions of cancers arising at 36 months or more from the last screen, which may mask a problem with significant implications for the success of the NHSBSP. PMID- 9368876 TI - Screening for diabetic retinopathy in primary care: retinal photography alone can be used efficiently and effectively to exclude those with sight threatening lesions. AB - BACKGROUND: Good screening performance of retinal photography and ophthalmoscopy together in screening for diabetic retinopathy in primary care have been reported. This study reanalysed the data to evaluate the screening performance of photography alone. METHODS: One thousand and ten patients screened by fundal photography and ophthalmoscopy were studied retrospectively. Fundal photographs were quality graded with poor quality pictures being excluded from the analysis. Each patient was reviewed initially by both retinal photographs and ophthalmoscopy by an ophthalmologist, the "gold standard". Six months later the fundal photographs were reviewed and reported in a blinded manner by the ophthalmologist. RESULTS: Two thousand and fourteen photographs were obtained, of which 162 (8%) had to be excluded because of poor quality. On review of the remaining 1852 photographs in isolation, of 77 cases of severe retinopathy as determined by the "gold standard", 67 had severe changes on photography- detection rate 87%. Of the 1775 cases without sight threatening retinopathy only five were judged to have sight threatening changes on photography--false positive rate 0.3%. Considering sight threatening and background retinopathy together, the detection rate was 69% (257 of 375) and the false positive rate 1.6% (23 of 1477). CONCLUSION: Good quality fundal photographs alone seem specific enough to screen for sight threatening diabetic retinopathy, but will underdetect background retinopathy. PMID- 9368877 TI - Why the term "carrier screening" should not be abandoned. PMID- 9368879 TI - Identification and localization of an immunoreactive AMPA-type glutamate receptor subunit (GluR4) with respect to identified photoreceptor synapses in the outer plexiform layer of goldfish retina. AB - L-glutamate, the main excitatory synaptic transmitter in the retina, is released from photoreceptors and evokes responses in second-order retinal neurons (horizontal, bipolar cells) which utilize both ionotropic and metabotropic types of glutamate receptors. In the present study, to elucidate the functional roles of glutamate receptors in synaptic transmission, we have identified a specific ionotropic receptor subunit (GluR4) and determined its localization with respect to photoreceptor cells in the outer plexiform layer of the goldfish retina by light and pre-embedding electron-microscopical immunocytochemistry. We screened antisera to mammalian AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate) preferring ionotropic glutamate receptors (GluR 1-4) of goldfish retina by light- and electron-microscopical immunocytochemistry. Only immunoreactive (IR) GluR4 was found in discrete clusters in the outer plexiform layer. The cones contacted in this manner were identified as long-wavelength ("red") and intermediate wavelength ("green") cones, which were strongly immunoreactive to monoclonal antibody FRet 43 and antisera to goldfish red and green-cone opsins; and short wavelength ("blue") cones, which were weakly immunoreactive to FRet 43 but strongly immunoreactive with antiserum to blue-cone opsin. Immunoblots of goldfish retinal homogenate with anti-GluR4 revealed a single protein at M(r) = 110 kDa. Preadsorption of GluR4 antiserum with either the immunizing rat peptide, or its goldfish homolog, reduced or abolished staining in retinal sections and blots. Therefore, we have detected and localized genuine goldfish GluR4 in the outer plexiform layer of the goldfish retina. We characterized contacts between photoreceptor cells and GluR4-IR second-order neurons in the electron microscope. IR-GluR4 was localized to invaginating central dendrites of triads in ribbon synapses of red cones, semi-invaginating dendrites in other cones and rods, and dendrites making wide-cleft basal junctions in rods and cones; the GluR4-IR structures are best identified as dendrites of OFF-bipolar cells. The results of our studies indicate that in goldfish retina GluR4-expressing neurons are postsynaptic to all types of photoreceptors and that transmission from photoreceptors to OFF-bipolars is mediated at least in part by AMPA-sensitive receptors containing GluR4 subunits. PMID- 9368878 TI - Association of cortactin with developing neuromuscular specializations. AB - During the development of the neuromuscular junction (NMJ), motoneurons grow to the muscle cell and the nerve-muscle contact triggers the development of both presynaptic specialization, consisting of clusters of synaptic vesicles (SVs), and postsynaptic specialization, consisting of clusters of synaptic vesicles (SVs), and postsynaptic specialization, consisting of clusters of acetylcholine receptors (AChRs). Previous studies have shown that the activation of tyrosine kinases and the local assembly of an actin-based cytoskeletal specialization are involved in the development of both types of specializations. To understand the link between tyrosine phosphorylation and the assembly of the cytoskeleton, we examined the localization of cortactin in relationship to synaptic development. Cortactin is a 80/85 kD F-actin binding protein and is a substrate for tyrosine kinases. It contains a proline-rich motif and an SH3 domain and is localized at sites of active F-actin assembly. Using a monoclonal antibody against cortactin, its localization at developing NMJs in culture was observed. To understand the spatial and temporal relationship between cortactin and developing synaptic structures, cultured muscle cells and spinal neurons from Xenopus embryos were treated with beads coated with heparin-binding growth-associated molecule to induce the formation of AChR clusters and SV clusters and the localization of cortactin was followed by immunofluorescence. In untreated muscle cells, cortactin is often co-localized with spontaneously formed AChR clusters. After cells were treated with beads, cortactin became localized at bead-induced AChR clusters at their earliest appearance (1 h after the addition of beads). This association was most reliably detected at the early stage of the clustering process. On the presynaptic side, cortactin localization could be detected as early as 10 min after the bead-neurite contact was established. Cortactin enriched contacts later showed concentration of F-actin (at 1 h) and clusters of SVs (at 24 h). These data suggest that cortactin mediates the local assembly of the cytoskeletal specialization triggered by the synaptogenic signal on both nerve and muscle. PMID- 9368880 TI - Changes in the mRNAs encoding subtypes I, II and III sodium channel alpha subunits following kainate-induced seizures in rat brain. AB - Several lines of evidence underscore a possible role of voltage-gated Na+ channels (NaCH) in epilepsy. We compared the regional distribution of mRNAs coding for Na+ channel alpha subunit I, II and III in brains from control and kainate-treated rats using non-radioactive in situ hybridization with subtype specific digoxigenin-labelled cRNA probes. Labelling intensity was evaluated by a densitometric analysis of digitized images. Heterogeneous distribution of the three Na+ channel mRNAs was demonstrated in brain from adult control rats, which confirmed previous studies. Subtype II mRNAs were shown to be abundant in cerebellum and hippocampus. Subtype I mRNAs were also detected in these areas. Subtype III mRNAs were absent in cerebellar cortex, but significantly expressed in neurons of the medulla oblongata and hippocampus. The three subtypes were differentially distributed in neocortical layers. Subtype II mRNAs were present in all of the layers, but mRNAs for subtypes I and III were concentrated in pyramidal cells of neocortex layers IV-V. During kainate-induced seizures, we observed an increase in Na+ channel II and III mRNA levels in hippocampus. In dentate gyrus, subtype III mRNAs increased 3 h after KA administration to a maximum at 6 h. At this latter time, a lower increase in NaCh III mRNAs was also recorded in areas CA1 and CA3. NaCh III overexpression in dentate gyrus persisted for at least 24 h. In the same area, NaCh II mRNAs were also increased with a peak 3 h after KA injection and a return to control levels by 24 h. No changes in NaCh I mRNAs were seen. The KA-induced up-regulation in NaCh mRNAs probably resulted in an increase in hippocampal neuronal excitability. PMID- 9368883 TI - Towards more readily comprehensible procedures in disector stereology. PMID- 9368881 TI - Schwann cells responding to primary demyelination in vivo express p75NTR and c erbB receptors: a light and electron immunohistochemical study. AB - We have used quantitative and qualitative light microscope immunohistochemistry to examine the expression of p75NTR and c-erbB receptors in Schwann cells in a demyelinating lesion induced by the intraneural injection of lysophosphatidyl choline (LPC). We report that levels of p75NTR, c-erbB2 and c-erbB4, as assessed using image analysis of immuno-peroxidase labelled sections, and c-erbB3, as assessed by eye, increased within each lesion site soon after the initiation of myelinolysis, peaked between 5 and 8 days after induction of demyelination and fell to undetectable levels at the onset of remyelination. Pre-embedding immunoelectron microscopy confirmed that Schwann cells ensheathing demyelinated axons were p75NTR positive. Immunolabel decorated overlapping processes of neighbouring Schwann cells, suggesting that in this context p75NTR could play a role in juxtacrine signalling between reacting cells. We conclude that upregulation of p75NTR and c-erbB receptors is a constitutive Schwann cell response to an acute disruption of the axon-Schwann cell relationship. PMID- 9368882 TI - Putative odour receptors localize in cilia of olfactory receptor cells in rat and mouse: a freeze-substitution ultrastructural study. AB - Two different polyclonal antibodies were raised to synthetic peptides corresponding to distinct putative odour receptors of rat and mouse. Both antibodies selectively labelled olfactory cilia as seen with cryofixation and immunogold ultrastructural procedures. Regions of the olfactory organ where label was detected were consistent with those found at LM levels. Immunopositive cells were rare; only up to about 0.4% of these receptor cells were labelled. Despite chemical, species, and topographic differences both antibodies behaved identically in their ultrastructural labelling patterns. For both antibodies, labelling was very specific for olfactory cilia; both bound amply to the thick proximal and the thinner and long distal parts of the cilia. Dendritic knobs showed little labelling if any. Dendritic receptor cell structures below the knobs, supporting cell structures, and respiratory cilia did not immunolabel. There were no obvious differences in morphology between labelled and unlabelled receptor cells and their cilia. Labelling could be followed up to a distance of about 15 microns from the knobs along the distal parts of the cilia. When labelled cells were observed, this signal was detectable in two, sometimes three, sections taken through these cells while being consistently absent in neighbouring cells. This pattern argues strongly for the specificity of the labelling. In conclusion, very few receptor cells labelled with the antibodies to putative odour receptors. Additionally the olfactory cilia, the cellular regions that first encounter odour molecules and that are thought to transduce the odorous signal, displayed the most intense labelling with both antibodies. Consequently, the results showed these cilia as having many copies of the putative receptors. Finally, similar patterns of subcellular labelling were displayed in two different species, despite the use of different antibodies. Thus, this study provides compelling evidence that the heptahelical putative odour receptors localize in the olfactory cilia. PMID- 9368884 TI - [The problems in diagnosis in MRI]. PMID- 9368885 TI - [Evaluation of brain evoked potentials in the detection of subclinical hepatic encephalopathy in cirrhotics]. AB - Brainstem auditory evoked potentials (BAEP), visual evoked potentials (VEP) and short latency somatosensory evoked potentials (SSEP) were examined in 30 nonalcoholic liver cirrhotics without clinically detectable hepatic encephalopathy and 30 healthy controls. In the cirrhotics, all peak latencies of the three kinds of evoked potentials, the interpeak latencies (IPLs) I-V, III-V of BAEP and the IPLs N13-N20, N13-P25 of SSEP were significantly prolonged compared with the controls, respectively. The amplitudes of P100, N125 of VEP were significantly lowered in the cirrhotics than those of the controls. Abnormal BAEP test and abnormal SSEP test results were found in both 60% of the cirrhotics, while VEP tests showed abnormalities in only 36.7%. In total, abnormal evoked potential test of one or more kinds were found in 90% of the cirrhotics. It is concluded that in cirrhotic patients, before the appearance of clinically encephalopathy, there were already brain evoked potential abnormalities or brain function changes. Our results argue in favor of the three kinds of evoked potential as the combined investigation for the sensitive and objective diagnosis of subclinical hepatic encephalopathy in patients with nonalcoholic cirrhosis. PMID- 9368886 TI - [Effects of melatonin and diazepam on the eye movement and postural muscle tone in decerebrate cats]. AB - We studied the effects of melatonin and diazepam on eye movement and muscle activity in decerebrate cats, and results were compared with those obtained from carbachol injection into the pontine reticular formation which was supposed to be a model of REM sleep. In precollicular postmammillary decerebrate cats, the horizontal eye movement and the activity of bilateral triceps surae muscles were recorded under three conditions: (1) microinjection of carbachol into the rostral pontine reticular formation; (2) intravenous administration melatonin; and (3) diazepam. Both rapid eye movement and reduction of muscle activity were induced by carbachol injection, while only reduction of muscle activity was induced by diazepam administration. Neither rapid eye movement nor reduction of muscle activity was induced by melatonin administration in this animal preparation. From these results, we speculated that the inhibitory effect of diazepam on muscle tonus was not manifested through activation of the brainstem REM generating system. It is known that the melatonin receptors are located in several sites of central nervous system, such as suprachiasmatic nucleus, and not in the brainstem and spinal cord. The present results of melatonin administration may support this fact in view of behavioral aspects. PMID- 9368887 TI - [Japanese cases of hyperostosis frontalis interna]. AB - Although hyperostosis frontalis interna is common in the western countries, it has been rarely reported in the literature in Japan. We had a chance to observe 5 cases diagnosed as hyperostosis frontalis interna. They were found among 10,902 patients who came to our hospital from August 1, 1993 to September 30, 1995. All the patients in these five cases are females aged 67 to 85 (mean = 74.2 years). Four of the 5 cases had been treated as hypertension, 2 as diabetes mellitus, and 1 as hyperlipoidemia. Two cases were accompanied by unruptured aneurysms. The pathology of one case accompanied by chronic subdural hematoma revealed no apparent development of Haversian systems of bone. It seems that the prevalence of this disease in Japan would increase from now on due to the fact that the life style and the diet among Japanese people has been getting westernized. PMID- 9368888 TI - [Three-dimensional brain mapping using fMRI]. AB - Functional mapping of the activated brain, the location and extent of the activated area were determined, during motor tasks and sensory stimulation using fMRI superimposed on 3 D anatomical MRI. Twelve volunteers were studied. The fMR images were acquired using a 2 D gradient echo echo planar imaging sequence. The 3D anatomical MR images of the whole brain were acquired using a conventional 3D gradient echo sequence. Motor tasks were sequential opposition of fingers, clenching a hand and elbow flexion. Somatosensory stimulation were administered by scrubbing the palm and sole with a washing sponge. Visual stimulation consisted of full visual field stimulation. Data were analyzed by the cross correlation method. Transversal fMR images and anatomical images were reconstructed using both volume-, surface-rendering methods, and reconstructed for coronal and sagittal sections. Activated areas were expressed using the three primary colors. Motor tasks activated the contralateral primary motor area (M1), the primary somatosensory area (S1) and the supplementary motor area (SMA). Somatosensory tasks activated the contralateral S 1, M1 and secondary sensory area (S2). Activated areas during full visual field stimulation was observed in the bilateral occipital lobe, including both the primary cortex. Three dimensional brain mapping allowed visualization of the anatomical location and extent of the activated brain during both motor task and sensory stimulation. Using this method we could obtain a functional map similar to the Penfield's schema. PMID- 9368889 TI - [A man with systemic lupus erythematosus presenting with spastic paraplegia]. AB - We report a 38-year-old man systemic lupus erythematosus who presented with an acute onset of paraplegia and urinary retention. The man had a 12-year history of nodular cutaneous mucinosis and arthralgia. In 1994, he was admitted to our hospital with a sudden onset of weakness and numbness of the right leg followed by an emergence of similar symptoms in the left leg. His elder sister had died at 16 years of age after suffering from systemic lupus erythematosus for 6 years. On examination, the patient had skin rash on his chest, back, head, forehead, and extremities. The neurological examination revealed that his tongue deviated to the right on protrusion. The muscle power was reduced to 2-3/5 in the right leg and to 4/5 in the left leg. The sensory disturbance was noted in the lower extremities with predominant involvement of the right leg. Reflexes were increased in the right biceps, triceps, both patellas, and Achilles tendons. Babinski sign was noted bilaterally. Urinary retention and constipation were also noted. The results of the blood cell count and hepatic and renal function tests were normal. Serum levels of C-reactive protein and complements (C3, C4, CH50) were also normal. Serological examinations showed increased anti-DNA antibody (14 U/ml, [normal, < 6]). Antinuclear antibody was positive at a titer of 1:1380. CSF study showed an increased protein concentration of 83 mg/dl and an IgG level of 14 mg/dl with a normal number of cells. MR images revealed a T1-low, T2-high signal lesion at the upper part of the left ventral medulla. MR images of the brain and spinal cord were normal. The patient was diagnosed as having SLE. High dose intravenous methylprednisolone (1 g/day) pulse treatment that was started 25 days after the onset of neurological symptoms, produced partial relief. Our case presented with paraplegia with a focal lesion in the left upper ventral part of the medulla on MR images. The incidence of male SLE is low, and paraplegia is a rare complication of SLE. Thus, the medullary lesion in SLE observed in our case appears to be rare. SLE should be considered as a cause of acute onset paraplegia or myelopathy. PMID- 9368890 TI - [Cerebral infarction due to stenosis of the bilateral internal carotid artery in Turner's syndrome]. AB - A 43-year-old woman was admitted into our hospital because of aphasia and right hemiparesis. Computed tomographic scan demonstrated border zone infarction in the anterior and middle cerebral artery. Magnetic resonance imaging scans showed the borderline area between the terminal branches of the lenticulostriate arteries and the perforating branches of the middle cerebral artery. Digital subtraction ICA angiogram showed severe narrowing of the distal portion of the right and left ICA. A pattern analysis of ambulatory blood pressure monitoring (ABPM) was carried out in this patient, and it was showed "dipper type". Laboratory data was elevated excretion of pituitary gonadotropines and low estrogen excretion. Chromosome analysis revealed the 45, X/46, XX. She was diagnosed with mosaic type of Turner's syndrome. The cerebrovascular abnormality might be due to congenital hypoplasia of arteries, and declining of blood pressure during sleep was possible significant factors in the pathogenesis of cerebral infarction in this patient. PMID- 9368891 TI - [An operated case of intractable occipital lobe epilepsy associated with calcification in the occipital lobe]. AB - We reported a 20-year-old female of intractable occipital lobe epilepsy associated with calcification in the left occipital lobe. She developed seizures since 2 years old and electroencephalography showed paroxysmal activities on the left occipital area. At 8 years old, partial resection of the lesion and interictal spike focus under intraoperative corticography guidance was performed, but the favorable seizure outcome was not obtained. At the age of 20 years old, the frequency of her seizures has increased and admitted to our department. Preoperative evaluation with chronic invasive subdural recording showed that the ictal zone was located in the inferior (tentorial) surface and convexity of the left occipital lobe. Functional mapping involving cortical stimulation and cortical recording of pattern-reversal visual evoked potentials demonstrated that the ictal onset zone was not in the visual area. Following cortical resection of the ictal onset zone and multiple subpial transection on the surrounding cortex, she had good relief with less than one minor seizure per 1-3 months. Histological findings of the resected specimen were consistent with those of Sturge-Weber syndrome. Thus chronic invasive subdural recording may improve seizure outcome in patients whose epileptogenic area was located near the visual field. PMID- 9368892 TI - [A case of superficial siderosis of the central nervous system with bilateral vestibular dysfunction]. AB - A 58-year-old woman developed slowly progressive hearing loss, anosmia, and unsteady gait. She had neither repeated episode of headache nor a past history of neurosurgical operation or head injury. Neurological examination revealed anosmia, moderate degree of sensorineural hearing loss. She showed loss of caloric response bilaterally. No nystagmus was found. Romberg sign was present. No cerebellar ataxia was noted in the finger-to-nose or the heel-to-knee test. No adiadochokinesis was noted. Deep tendon reflexes were increased in both upper and lower extremities. Sensation was intact. She showed disturbance of the righting reflex in the tilt-table examination. CSF were under normal pressure, xanthochromic with siderophages. CSF total protein and ferritin level were elevated. T2-weighted image (TE4000/TR100) of high field strength magnetic resonance imaging (MRI) showed marginal hypointensity of the brain stem, the Sylvian fissures, the tips of temporal lobes, anterior cerebellar surfaces and the entire spinal cord. Angiography of the cerebral vessels and spinal arteries failed to identify the source of bleeding. It seemed likely that she had lost bilateral vestibular and auditory functions caused by hemosidelin deposition to her eighth nerves which are often affected by this disorder. Her disturbance of gait and station was apparently similar to cerebellar ataxic gait, however, she did not have limb ataxia. The electronystagmogram revealed marked degree of vestibular dysfunction (VOR) and relative sparing of cerebellar function (OKN). Her disturbance of the righting reflex in the tilt-table examination and the characteristic feature of her Romberg sign with directional preponderance also indicate that the bilateral loss of vestibular functions, i.e., vestibular ataxia caused her dysequilibrium syndrome. It is our impression that vestibular ataxia might precede cerebellar ataxia commonly reported so far. PMID- 9368893 TI - [A case of giant cell-rich gliosarcoma]. AB - We report a case of gliosarcoma with numerous giant cells resembling ganglion cells and having clear nucleoli. A 75-year woman was admitted to our hospital suffering from progressive left hemiparesis and ambulatory disturbance of one week's duration. CT and MRI studies showed ring enhancement on a clear margin mass in the right parieto-occipital lobe. The mass was totally removed macroscopically. Her left hemiparesis had improved and self walk came to be possible. But the tumor was regrowthed during next two months and she died for three months and a week. The gross and microscopic appearances of the tumors showed the double structure. The surface of the tumor was well enhanced and consisted of soft, gray, and easily bleeding tissue. The central core, however, was poorly enhanced and consisted of hard, yellow, non-bleeding tissue. Macroscopically, the central area included numerous giant ganglion-like cells which were negative for GFAP but positive for EMA in the cytoplasm. These giant cells had abundant collagen fibers and were surrounded by such fibers. Microscopic findings of the surrounding area included numerous spindle shaped cells which were positive for GFAP and vimentin. The origins of giant cells or tumor tissues have long been discussed, but no consensus has yet been obtained. Therefore, we speculated as to the origin in our patient based on immunohistochemical study and the findings of electronmicroscopy. We concluded, in sharp contrast to the old theory of one origin, epithelial tissue of a hamartomatous nature existed initially, followed by the growth of malignant tissue of a reactive astrocytic tumor with a sarcomatous component. PMID- 9368894 TI - [MR demonstration of multiple reversible cerebral lesions in eclampsia]. PMID- 9368895 TI - [Skew deviation]. PMID- 9368896 TI - [A 85-year-old woman with one year history of convulsion, dementia, and consciousness disturbance]. AB - We report a 85-year-old woman who died after one year history of convulsion, dementia, and consciousness disturbance. She was apparently well until January 6, 1995 when she was 85 year old; on that evening, she suddenly stated that some one was in her room and she became confused. A local MD gave her diazepam and she fell into sleep. At 3 o'clock in the following morning, she developed tonic clonic convulsion in her right lower extremity which showed a march to her right upper extremity and the left lower extremity. She was admitted to our hospital. On admission, she was comatose with respiratory acidosis. She was intubated and placed on a ventilator. She was treated with intravenous phenytoin. She gradually gained consciousness and became alert. Respiration became normal. Her MRI revealed ventricular dilatation, fronto-parietal cortical atrophy, and a T1-low and T2-high signal intensity lesion in the left occipital lobe. She was discharged for out patient follow-up on February 4, 1995. Since then, she noted loss of memory and small step gait. A follow-up CT scan revealed a mass lesion which showed a ring-shaped enhancement in the left occipital lobe and was admitted again. On admission, she was alert but markedly demented. The optic fundi was unremarkable, but she appeared to have right homonymous hemianopsia. No motor weakness was noted. In Gd-DTPA enhanced MRI, the above tumor showed a ring enhancement. The diagnosis of glioblastoma was entertained, however, considering her age, she was treated with intravenous glycerol and intramuscular steroid. She was discharged for out-patient follow-up on July 15, 1995. Her gait disturbance had progressively become worse and she developed nausea and vomiting and was admitted again on October 2, 1995. On admission, she was somnolent and markedly demented. Brain stem responses were retained normally. She was unable to stand or walk. Deep tendon reflexes were slightly increased in the right upper extremity and the plantar response was extensor on the right. Her hospital course was complicated by respiratory tract infection and respiratory acidosis. She expired on November 2, 1995. The patient was discussed in a neurological CPC and the chief discussant arrived at the conclusion that she had a glioblastoma involving the left occipital lobe and the adjacent areas. Post-mortem examination revealed an infiltrating tumor in the left occipital lobe. On microscopic examination, the tumor was very cellular; nuclear atypism was marked and tumor cells undergoing mitosis were seen. In some areas, capillary proliferation was seen. Histologic characteristics were consistent with glioblastoma. PMID- 9368897 TI - Malaria toxins from P. chabaudi chabaudi AS and P. berghei ANKA cause dyserythropoiesis in C57BL/6 mice. AB - The lack of correlation between parasitaemia and anaemia in severe malaria indicates that factors in addition to schizont rupture or erythrophagocytosis contribute to anaemia. We asked whether malaria toxin (MT) from Plasmodium berghei or P. chabaudi might impair erythropoiesis. Daily intraperitoneal injection of MT into C57BL/6 mice induced a transient reduction of RBC values by 25-30% after about 2 weeks, followed by increased haematopoiesis in the spleen as compared to mice receiving uninfected RBC preparations. There was a 3 (P. berghei) to 8-fold (P. chabaudi) increase of total proliferative activity in the spleen. Flow cytometric analyses showed that this was accompanied by some differentiation of TER-119 positive erythroid cells and of Gr-1 positive myeloid cells. Erythroid and myeloid progenitor cell-derived colony assays confirmed these results and revealed an increase in the number of CFU-E (< or = 200-fold), BFU-E (< or = 10-fold) and CFU-GM (< or = 20-fold) in the spleen of MT treated mice, as compared to controls. PMID- 9368898 TI - Malaria toxins: effects on murine spleen and bone marrow cell proliferation and cytokine production in vitro. AB - The ability of deproteinated malaria exoantigens from Plasmodium falciparum (Pf MT) and P. berghei ANKA (PbA-MT) to activate murine haematopoietic cells was analysed in vitro. Malaria toxins (MT) of both plasmodium species induced cell proliferation and the production of IFN-gamma in overnight and long-term (5 days) spleen and bone marrow cultures and a reduction of the number of TNF-alpha spot forming cells (SFC). When added to cells of malaria-experienced animals, MT decreased the number of IL-4 SPC and increased the number of IL-5 SPC. However, the same proliferative and IFN-gamma induction properties as in naive cells were observed. Simultaneous addition of IL-2 and PbA-MT to spleen cells inhibited the proliferation but increased the IFN-gamma production usually induced by IL-2. Flow cytometric analysis revealed that the addition of MT triggered an expansion of CD3+ and GR1+ cell populations. Our results suggest that malaria toxins of different species can induce an immediate and strong proliferation and a TH1-type cytokine release by murine cells, independently of previous in vivo priming. PMID- 9368899 TI - Different Babesia canis isolates, different diseases. AB - Using surface immunofluorescence isolate-specific antigens were detected on the membrane of erythrocytes infected with Babesia parasites. In addition, the strains reacted differently with Plasmagel in that the European isolate (B.c. canis) could be purified on Plasmagel effectively, whereas infected erythrocytes of the South-African isolate (B.c. rossi) could not. Experimental infection of dogs with Babesia canis isolates from geographically different areas revealed different pathology. The European isolate obtained from France exhibited transient parasitaemia, usually below 1%, associated with low PCV values and congestion of internal organs. Clinical disease was correlated with an effect on the coagulation system, and not with peripheral parasitaemia. Infection of dogs with South-African-derived isolate induced high parasitaemia usually much higher than 1%, which required chemotherapeutic treatment. In these animals clinical disease was correlated with peripheral parasitaemia and not with parameters of the coagulation system. The results show that the etiology of disease caused by these isolates of B.c. canis and B.c. rossi is different. This might have implications for the development of vaccines against these infections. PMID- 9368900 TI - Chagas' disease: reactivity against homologous tissues induced by different strains of Trypanosoma cruzi. AB - We have previously reported that the mechanisms of neuromyopathic damage induced by Trypanosoma cruzi are mediated by T cells and are parasite-strain dependent. In the present study our aim was to determine whether the humoral response against muscle and nervous system is also parasite-strain dependent. Of the sera from mice infected with RA and CA-I. T. cruzi strains, 93% reacted against antigens of the nervous system (sciatic nerve, spinal cord and brain). No differences in the ability to recognize heart antigens were found between RA (48%) and CA-I (63%) antisera. Reactivity against skeletal muscle was only relevant in anti-CA-I sera at 270 days post-infection. Each of the antisera assayed in Western blots developed a particular antigenic pattern, but 3 antigens in the nervous system of molecular weight 48, 60 and 70 kDa were detected by 42, 28 and 23% of the sera, respectively. On the other hand, deposits of IgG were observed at the interstitial matrix in sciatic nerve and as endomisial and sarcolemmal patterns in skeletal muscle by IFAT for both RA and CA-I antisera. Absorption of sera with parasite antigens did not abolish the autoreactivity. Our results suggest that major serum autoreactivity from T. cruzi-infected mice is not parasite-strain dependent and does not arise from molecular mimicry. PMID- 9368901 TI - The in vitro development of the pentastomid Porocephalus crotali from the infective instar to the adult stage. AB - The in vitro development of the pentastomid Porocephalus crotali from the infective, seventh (VII) instar, dissected from the tissues of rat intermediate hosts, to the adult male (X) and female (XI) instars, normally resident in the lung of rattlesnake definitive hosts, is described. The culture medium comprised washed human blood cells, resuspended in bovine serum (50:50, v/v), with 20% minimum essential medium and antibiotics. Two batches of approximately 100 pentastomids, maintained at a density of 2 worms/ml, were cultured in 500 ml bottles in an atmosphere of 5% CO2 in air at 28 degrees C. Culture bottles were rotated slowly on a Rollacell system and the medium was replenished every 2-3 days. Growth was monitored at various intervals by weighing worms, measuring cast cuticles with attached moulted hooks recovered from the medium, and by dissecting worms for measurements of various organ systems. Three moults separated the infective and adult male instar, whereas 4 moults were necessary in the case of females. In both cultures natural mortality was about 10% over a 160-day period, by which time 33-51% of females and 62-70% of males had reached the terminal instar. Some males attained full sexual maturity with seminal vesicles loaded with viable sperm: such males were indistinguishable from males recovered from naturally infected rattlesnakes. However, females never achieved full size, even after 200 days, and although copulation did not occur in vitro, some females became patent. PMID- 9368902 TI - Meloidogyne javanica surface proteins: characterization and lability. AB - Characterization of surface coat (SC) proteins including carbohydrate-binding proteins and glycoproteins of the plant-parasitic nematode Meloidogyne javanica 2nd-stage juvenile (J2) is reported. Extraction of surface proteins with sodium dodecyl sulfate (SDS) and separation by denaturing polyacrylamide gel electrophoresis (SDS-PAGE) results with bands at 6, 9, 14, 22, 26, 31, 46, 49, 58, 66, 80, 205 and 250 kDa. On Western blots, the neoglycoprotein, fucosylated-, mannosylated- and glucosylated-bovine serum albumin, reacted with the 14, 22, 26, 58 and 66 kDa bands. The lectins, Concanavalin A and wheat-germ agglutinin (WGA) labelled surface protein bands of 6, 9, 14, 31, 58 and 66 kDa; WGA also labelled the 22 and 26 kDA bands. Biotin reagents were used to specifically trace surface proteins on live J2. SDS-PAGE of biotinylated J2 extracts revealed only 2 specific biotin-protein bands at 46 and 49 kDa. The labile and transitory nature of Meloidogyne javanica SC was demonstrated by the dynamics of human red blood cells (HRBC) adherence to J2 of different ages. HRBC adherence was also used to demonstrate the SC recovery of detergent-treated J2, which was further exhibited in the SDS-PAGE profiles. PMID- 9368903 TI - Reduced genetic variability within coding and non-coding regions of the Echinococcus multilocularis genome. AB - Echinococcus multilocularis, a vulpine intestinal tapeworm, is the causative agent of alveolar echinococosis in humans, one of the most severe and lethal parasitic infections in man. To date, there is very little knowledge about the genetical polymorphism of this parasite. To assess sequence polymorphism, we analysed a sample of 33 E. multilocularis isolates from Europe, North America and Asia by PCR-SSCP followed by nucleotide sequencing. This assessment was performed comparatively to sheep, cattle and pig E. granulosus strains. Coding (nuclear antigen B and mitochondrial NADH dehydrogenase genes) and non-coding (introns of actin and homeobox-containing genes) regions of the parasite genome were chosen as targets. Since the estimated nucleotide diversity among genotypes of E. multilocularis were, in general, 10 times lower than among the recognized different strains of E. granulosus, we suggest that the conventional classification of the former species in 2 separated strains (European and North American) should be reviewed. PMID- 9368904 TI - Heligmosomoides polygyrus superantigen: differential response with mouse and human lymphocytes. AB - The interaction between Heligmosomoides polygyrus superantigen and human peripheral blood mononuclear cells (PBMC) was evaluated. Parasite homogenate and excretory-secretory proteins from both L4 larvae and adult worms were examined for their ability to stimulate, and be presented by, human cells. Proliferation assays using PBMC from 3 human volunteers indicated that naive cells were stimulated by H. polygyrus superantigen. Antigen presenting cells (APC) from a number of human donors were able to successfully present H. polygyrus' superantigen to mouse T cell hybridomas. However, this ability varied according to the source of the superantigen, and human APC, in contrast to APC from mice, could only present the superantigen contained within parasite homogenate. Also, in contrast to the situation with mice, human APC could present H. polygyrus superantigen to stimulate mouse T cells expressing not only TCR V beta 8.1, but also TCR V beta 7. Therefore, H. polygyrus superantigen can successfully stimulate, and be presented by, human PBMC of different MHC haplotypes, although the cellular mechanisms appear to be different from those observed in the mouse. PMID- 9368905 TI - Human Toxocara infection of the central nervous system and neurological disorders: a case-control study. AB - Infection with Toxocara canis is a common world-wide human helminthiasis, which rarely elicits central nervous system (CNS) impairment. A case-control study to investigate this discrepancy was carried out, in which the cases were 27 adult neurological inpatients for whom a definite aetiological diagnosis was lacking, and for whom positive immunodiagnosis of toxocariasis had been obtained, both in cerebrospinal fluid (CSF) and in serum. Two control groups were used. Controls were adult inpatients with other neurological diseases who had no evidence of T. canis infection of the CNS. Multivariate logistic regression analysis did not reveal any positive relation between case status and clinical signs. A significant association was observed between case status and an elevated CSF cell count. Rural residence, ownership of dogs, and dementia were shown to be risk factors for toxocaral infection of CNS. These results suggest that migration of T. canis larvae in the human brain does not frequently induce a recognizable neurological syndrome but is correlated with the association of several risk factors including exposure to dogs, a status possibly responsible for repeated low-dose infections. PMID- 9368906 TI - Experimental Oesophagostomum dentatum infections in the pig: worm populations at regular intervals during trickle infections with three dose levels of larvae. AB - A trickle infection experiment was undertaken to study in detail the population dynamics of Oesophagostomum dentatum in pigs. Three groups of 32 pigs were inoculated via the feed twice weekly with 100 (Group A), 1000 (Group B) or 10,000 (Group C) O. dentatum infective larvae (L3). Five pigs from each group were killed 2, 4, 8, 12, 16, and 20 weeks after the first inoculation (p.i.) to determine their worm burdens. Weekly faecal egg counts were determined. At slaughter, worms were counted, differentiated according to sex and developmental stage, and their length measured. Faecal egg counts ranked with dose rate until week 15, but later were more variable. The proportion of the total number of L3 administered which were recovered at slaughter inversely ranked with dose rate. In group C it decreased over time, whereas in groups A and B there was no consistent pattern. Worm fecundities (epg/female) in groups A and B were higher than in group C. The lengths of the female worms increased over time, whereas the lengths of the male worms remained approximately constant from week 8. The study suggests reduced establishment of incoming larvae and lower fecundity of the female worms at high dose levels. PMID- 9368907 TI - Actions of the anthelmintic ivermectin on the pharyngeal muscle of the parasitic nematode, Ascaris suum. AB - The anthelmintic invermectin has a number of effects on nematodes which result in changes in behaviour, particularly locomotion, including paralysis and an inhibition of feeding. This paper describes the application of an in vitro pharmacological approach to further delineate the action of ivermectin on feeding behaviour. Contraction of Ascaris suum pharyngeal muscle was monitored using a modified pressure transducer system which detects changes in intrapharyngeal pressure and therefore contraction of the radial muscle of the pharynx. The pharynx did not contract spontaneously. However, serotonin (5-HT, 100 microM) stimulated rhythmic contractions and relaxations (pumping) at a frequency of 0.5 Hz. gamma-Aminobutyric acid (GABA) and glutamic acid inhibited the pumping elicited by 5-HT. The duration of inhibition was concentration dependent (1-1000 microM) with a threshold of 1 microM and 10 microM respectively (n = 8). Ivermectin also inhibited pharyngeal pumping (1-1000 nM). At lower concentrations, ivermectin (1-10 pM) potentiated the GABA and glutamate inhibition, so that inhibition occurred at concentrations which were below threshold in the absence of ivermectin. These data provide evidence that the pharynx is a site for the action of ivermectin. Thus interruption of pharyngeal processes such as, feeding, regulation of hydrostatic pressure and secretion may provide a new site of anthelmintic action. PMID- 9368908 TI - Anti-thrombotic and anti-inflammatory activities of protopine. AB - The effects of protopine on human platelet aggregation and arachidonic acid (AA) metabolism via cyclooxygenase (COX) and lipoxygenase (LOP) enzymes were examined. Platelet aggregation induced by various platelet agonists (AA, ADP, collagen and PAF) was strongly inhibited by protopine in a concentration-related manner. The IC50 values (microM) of protopine (mean +/- SEM) against: AA; 12 +/- 2: ADP; 9 +/ 2: collagen; 16 +/- 2 and PAF; 11 +/- 1, were much less than those observed for aspirin. In addition, protopine selectively inhibited the synthesis of thromboxane A2 (TXA2) via COX pathway and had no effect on the LOP pathway in platelets. In vivo, pretreatment with protopine (50-100 mg kg-1) protected rabbits from the lethal effects of AA (2 mg kg-1) or PAF (11 micrograms kg-1) in dose-dependent fashion. Protopine (50-100 mg kg-1) also inhibited carrageenan induced rat paw oedema with a potency of three-fold as compared to aspirin. These results are suggestive that protopine acts as a potent inhibitor of thromboxane synthesis and PAF with anti-inflammatory properties. PMID- 9368909 TI - The role of isocolloidoosmotic synthetic colloid addition to St. Thomas Hospital cardioplegic solution for cardioprotection in isolated perfused rat hearts. AB - Cardiac transplantation is a prominent development in the treatment of patients with severe cardiac diseases. If it is not possible to transplant the heart immediately after removing it from the donor, procedures for preparing, protecting, storing and transferring of the heart constitute a major portion of this study. Selecting the best method among those used for cardioprotection is still been debated. This experimental study investigated whether isocolloidoosmotic solution in addition to St. Thomas Hospital cardioplegic solution would give better cardioprotection. Wistar rat hearts were isolated and perfused by the Langendorff method (n = 6 for each group). In the control group after stabilisation, the hearts were arrested while perfused with St. Thomas Hospital cardioplegic solution for 3 min, then they were placed in cardioplegic solution at 4 degrees C for 6 h. Afterwards the hearts were reperfused. In the experimental groups, modified gelatin fluid (30 g/l) or HES 200/0.5 (50 g/l) or dextran 70 (25 g/l) was added to the cardioplegic solution. Maximum contractility, +dF/dtmax, -dF/dtmax, heart rate, contractility rate product, coronary flow and lactate dehydrogenase, creatine phosphokinase enzyme leakage were measured in all groups during pre-ischemic and post-ischemic periods (10 min after reperfusion). At the end of each experiment, the hearts were weighted and tissue levels of lipid peroxide, expressed in terms of thiobarbituric acid reactive substances, malondialdehyde, glutathione (an important intracellular antioxidant) and ATP were measured. Non-ischemic tissue levels of malondialdehyde, glutathione and ATP were also measured in another group (n = 6). There was no statistically significant difference among the simultaneous experimental and control groups in any criteria evaluated (P > 0.05). The addition of synthetic colloids to the standard cardioplegic solution did not provide further protection except for the gelatin group in which recovered contractile force was not significantly different from the group's initial values. This effect may be explained by its degradation to amino acids which may play a substrate role. PMID- 9368910 TI - Bolus magnesium infusion in humans is associated with predominantly unfavourable changes in platelet aggregation and certain haemostatic factors. AB - The purpose of this study was an attempt to extrapolate favorable observations on the effects of magnesium on platelets and haemostasis from animal models to humans. Intravenous magnesium in the treatment of acute myocardial infarction has been tested in several large clinical trials and remains controversial. The mechanism for the cardioprotective properties of magnesium is unknown. Based on experimental studies, several different hypotheses have been advanced to explain the benefits of magnesium including it's effects on platelets and haemostasis. However, few studies have analysed such a relationship in humans. This project was designed to assess the effect of bolus magnesium infusion on ex vivo platelet aggregation and certain haemostatic parameters in healthy volunteers. One gram of magnesium was diluted in 50 ml of D5W and infused over a period of 15 min. The changes of platelet aggregability, plasma antithrombin-III, Protein C, total Protein S, fibronectin, endothelin-1, as well as the metabolites of thromboxane and prostacyclin were determined prior to and immediately after magnesium infusion. RESULTS: Serum magnesium concentration increased from 2.10 +/- 0.08 at baseline to 3.12 +/- 0.13 mg dl-1 (P = 0.0002) post-infusion. Magnesium infusion was associated with a significant elevation in ADP (+19.3%); ristocetin (+13.6%); and collagen-induced platelet aggregation (+14.2%); an increase in plasma antithrombin-III (+10.3%) and thromboxane (+49.4%) when compared to pre-infusion levels. Against this, total Protein S (-20.7%), Protein C (-11.2%) and ET-1 ( 26.3%) plasma concentrations were markedly decreased. There were no significant differences in plasma fibronectin and prostacyclin levels. Contrary to expectations, magnesium infusion in human volunteers is associated with platelet activation and mostly small unfavourable changes in certain haemostatic factors. However, the observed changes were small and for the most part remained within the normal physiologic range. PMID- 9368911 TI - Pirlindole: a selective reversible inhibitor of monoamine oxidase A. A review of its preclinical properties. AB - Pirlindole is a tetracyclic compound that has been characterized as a potential antidepressant drug. It has pharmacological characteristics in common with both tricyclic antidepressants and classical irreversible monoamine oxidase inhibitors. Its main mechanism of action consists of a selective and reversible inhibition of monoamine oxidase A. Secondarily, it exerts an inhibitory effect on noradrenaline and 5-hydroxytryptamine reuptakes. It has no effect on the dopaminergic and cholinergic systems. It has only a low potential for amplifying tyramine and noradrenaline pressor effect, which makes one expect that it will not be at the basis of a 'cheese effect'. Pirlindole has an absolute bioavailability of between 20 and 30% due to an extensive first-pass effect. Orally, the Tmax varies between 2.5 and 6 h in the rat and 0.8 and 2 h in the dog. Two phases of elimination (7.5 and 34-70 h) are measured in the rat and three phases in the dog (1.3, 10.8 and 185 h); it is extensively metabolized. The rat eliminates mainly unconjugated products while the dog eliminates mostly conjugated products. Acute and chronic toxicological studies have not revealed potentially dangerous effects of the drug at the usual doses. It does not present measurable mutagenic, clastogenic or carcinogenic properties. Thus, pirlindole shows pharmacological, pharmacokinetic and toxicological properties which make it suitable for the management of depression. PMID- 9368912 TI - Effects of the combination antibiotic--EDTA-Tris in the treatment of chronic bovine endometritis caused by antimicrobial-resistant bacteria. AB - The combined effects of the uterine infusion of EDTA-Tris solution and antibiotics have been evaluated in 75 cases of slight, moderate or severe bovine endometritis which did not respond to local routine antimicrobial therapy. Antibiotic-resistant bacteria were isolated from uterine swabs. The cows were divided into three groups on the basis of the severity of endometritis and treated with 100 ml of sterile EDTA-Tris solution (250 mM EDTA and 50 mM tris, pH 8) and the same antibiotic used in the first unsuccessful treatment (oxytetracycline, enrofloxacin, lincomycin-spectinomycin or amikacin). Control groups consisting of six animals treated with antibiotic alone were used. Clinical evaluations performed 2, 15, 21, 42 and 63 days after treatment revealed good therapeutic results, as 53 cows showed a complete recovery with renormalization of the subsequent oestrus cycle. Artificial insemination was followed by pregnancy in about 90% of treated cows. In control animals the second treatment performed using only the antibiotic gave variable and unsatisfactory results, particularly in animals affected by severe endometritis. PMID- 9368913 TI - No sex-related pharmacokinetic and pharmacodynamic differences of captopril. AB - Captopril is an angiotensin-converting enzyme inhibitor (ACEI) used in the treatment of hypertension and congestive heart failure and has demonstrated its cardiovascular effects in experimental animal models, healthy volunteers and patients. The aim of this study was to find out whether or not differences in the pharmacokinetic profile and the haemodynamic response of a 100-mg single oral dose of captopril appeared between subjects of both sexes. Twenty-four young healthy volunteers (12 males and 12 females) took part in the trial. Blood samples to assess captopril plasma concentrations, determined by reverse phase high performance liquid chromatography (HPLC), as well as haemodynamic variables, were obtained before and at different times following drug intake. Pharmacokinetic parameters did not show significant sex differences. Systolic and diastolic blood pressure exhibited a statistically significant decrease between 0.5 and 8 h in both sexes. No significant sex-related differences were found. The drug exhibited a good tolerability. PMID- 9368914 TI - Effect of long-term administration of Hexarelin on the somatotrophic axis in aged rats. AB - The growth hormone-releasing peptide Hexarelin (Hexa; 80 micrograms/kg-1, s.c.) was administered for 30 and 60 days to old rats. The GH-releasing effect of Hexa was maintained during chronic treatment. At the end of the treatment, old rats were administered once with Hexa which elicited a greater GH response in rats chronically treated with the peptide than in those receiving a placebo. Pituitary GHmRNA concentrations were significantly lower in the older rats than in the younger animals, irrespective of Hexa treatment, while the GH protein content was similar in all the groups studied. The same was true for hypothalamic GHRH, whose synthesis was reduced in all the older animals but not in the young, in the presence of maintained concentrations of the peptide. Somatostatin mRNA concentrations were significantly higher in the hypothalami of older rats and administration of Hexa for 30 or 60 days brought the concentrations of somatostatin mRNA of aged rats to 'young' levels. Treatments with Hexa failed to alter the circulating levels of IGF-1. The data reported in this article indicate that long-term treatment with Hexa normalized some biological indices of somatotrophic function in aged rats. PMID- 9368915 TI - The effect of chronic stress on hepatic and gastric lipid peroxidation in long term depletion of glutathione in rats. AB - The effect of chronic stress (immobilization and cold) on hepatic and gastric thiobarbituric acid reactive substances (TBARS) and vitamin C levels were investigated in rats having long-term depletion of glutathione (GSH) by applying buthionine sulfoximine (BSO). GSH and vitamin C levels decreased and TBARS levels increased in the liver and stomach of rats subjected to stress. Long-term BSO administration along with stress caused no additional changes in these parameters. These results may indicate that long-term glutathione depletion did not potentiate stress-induced hepatic and gastric lipid peroxidation. PMID- 9368916 TI - Antiamnesic activity of metoclopramide, cisapride and SR-17 in the mouse passive avoidance test. AB - The effects of the administration of metoclopramide, cisapride and SR-17 on memory processes were evaluated in the mouse passive avoidance test. The administration of dicyclomine (0.1-3 mg kg-1 i.p.), immediately after termination of the training session, produced a dose-dependent amnesic effect. Metoclopramide (1-5 mg kg-1 i.p.), cisapride (0.5-2 mg kg-1 i.p.) and SR-17 (1-10 mg kg-1 i.p.), administered 20 min before the training session, prevented dicyclomine-induced amnesia. In the same experimental conditions piracetam (30 mg kg-1 i.p.), physostigmine (0.2 mg kg-1 i.p.) and CGP 35348 (100 mg kg-1 i.p.) prevented dicyclomine amnesia. At the highest effective doses, none of the drugs impaired motor coordination, as revealed by the rota-rod test, nor did they modify spontaneous motility, as revealed by the Animex test. These results suggest that metoclopramide, cisapride and SR-17 play an important role in the modulation of memory processes. On these bases, these compounds could be useful in the treatment of cognitive deficits. PMID- 9368917 TI - Brain cortex Na(+)-K+ ATPase activities in streptozotocin-diabetic and pentylenetetrazol-epileptic rats. AB - The aim of this study was to investigate the brain cortex Na(+)-K+ ATPase activity in rats made diabetic by streptozotocin and epileptic by pentylenetetrazol. Streptozotocin diabetic rats showed a significant decrease in brain cortex Na(+)-K+ ATPase activity whereas the pentylenetetrazol treatment caused no significant change in enzyme activity. On the other hand, no brain cortex Na(+)-K+ ATPase activity could be detected in all the diabetic rats treated with pentylenetetrazol. Our results concluded that reduced Na(+)-K+ ATPase activity in streptozotocin diabetic rats may contribute to the pathogenesis of metabolic complications of the central nervous system, and that the undetectable enzyme activity in diabetic convulsing rats may result from considerable damage or necrosis of brain tissue during pentylenetetrazol seizures. PMID- 9368918 TI - The effect of cyclosporine A and amlodipine on the activity of gamma-glutamyl transpeptidase in mouse cerebral cortex. AB - The effect of cyclosporine A (CsA) and dihydropyridine calcium channel blocker (CCB) amlodipine on gamma-glutamyl transpeptidase (GGT; EC 2.3.2.2) activity in mouse cerebral cortex was investigated. Mice received amlodipine (0.07 mg kg-1), CsA (10, 20 and 40 mg kg-1) and CsA in the above doses combined with amlodipine (0.07 mg kg-1) once daily, intraperitoneally for 5 days. The control group received saline. Amlodipine decreased GGT activity when compared to the control group. GGT activity in the cerebral cortex was decreased after treatment with CsA (20 and 40 mg kg-1), but was not changed after treatment with CsA in the 10 mg kg 1 dose as compared to the control group. CsA in doses of 20 and 40 mg kg-1, combined with amlodipine, increased GGT activity as compared to the control group groups received the same doses of CsA without amlodipine and received only amlodipine. However, CsA in the 10 mg kg-1 dose combined with amlodipine decreased GGT activity when compared to the control group, but did not show any statistical difference when compared to the groups treated only with amlodipine or CsA in the same doses. These results suggest that CsA and amlodipine may modulate GGT activity in mouse cerebral cortex. PMID- 9368919 TI - One-year treatment with cholecystokinin-octapeptide and secretin: effects on pancreatic trophism in the rat. AB - The effects of long-term administration of cholecystokinin octapeptide (CCK-8) with or without secretin on the pancreas were examined in groups of rats treated with: (1) CCK-8 (1 microgram kg-1); (2) secretin + CCK-8 (1 microgram kg-1 of each); or (3) saline, administered subcutaneously twice daily for 5 out of 7 days for 6 or 12 months. A number of rats from all groups were studied for: (1) pancreatic size and biochemical composition (n = 6 for each group); (2) pancreatic secretion in the anesthetized state (n = 5 for each group); and (3) pancreatic histology (n = 6 for each group) after a 6-month treatment period. The rest of the animals treated for an additional 6-month period (n = 13 for each group) were examined for pancreatic size and histology. CCK-8 increased the weight of the pancreas and its contents of DNA, protein, trypsinogen, chymotrypsinogen, proelastase, secretory trypsin inhibitor and amylase, but not that of lipase when given for 6 months, whereas administration of secretin + CCK 8 doubled the pancreatic content of lipase and increased all trophic parameters (except the amylase content) over those of CCK-8-treated rats. Maximum pancreatic volume and protein outputs in response to CCK-8 were higher in both of the hormone-treated groups than in the control; the sensitivity to the secretory action of CCK-8 was not altered. Pancreatic mass increased in response to either treatment after 12 months as well. Histological examination did not reveal pancreatic neoplasia in either group. The results indicate that long-term administration of CCK-8 or secretin + CCK-8 in rats results in sustained pancreatic hypertrophy and hyperplasia with secretory hyperfunction with no evidence of neoplastic alterations. PMID- 9368920 TI - Better comparisons of antiepileptic drugs: what measures of efficacy? AB - With the licensing of new antiepileptic drugs there is an obvious need for the determination of the comparative efficacy, tolerability and overall effectiveness against standard (existing) antiepileptic drugs. Such data can only be determined within the context of well-designed randomised clinical trials (RCTs). Such comparative monotherapy studies may form a part of phase III drug development programmes for a new antiepileptic drug. They may be commenced once there is satisfactory evidence for efficacy and safety derived from placebo-controlled add on studies in more refractory populations of patients. In this manuscript definitions of outcomes such as effectiveness, efficacy, and tolerability are given. Health-related quality of life measures are presented, and it can be argued that such measures should be a primary outcome variable. However, there is little evidence that any quality of life measures have sufficient validity and sensitivity to be a useful tool in the comparison of drug treatments for epilepsy. Different populations can be studied in 'withdrawal to monotherapy' designs. In such studies patients poorly controlled on their existing therapy are randomised to receive different monotherapy regimes with withdrawal of their existing antiepileptic drugs. This clinical trial design has not been used in genuine comparisons between antiepileptic drugs and the efficiency of this approach has yet to be determined. Experience from studies comparing monotherapy would suggest that differences in efficacy between antiepileptic drugs in the target populations may be difficult to detect. Differences likely exist between the incidence and profile of adverse effects between different drugs. The main benefit of new antiepileptic drugs may be in reducing the incidence and severity of adverse reactions compared to older drugs and in doing so they may prove to be more effective. PMID- 9368921 TI - Evaluation of drug treatment outcome in epilepsy: a clinical perspective. AB - This article provides a comprehensive discussion of clinical outcome measures used in trials aimed at assessing the efficacy and safety of antiepileptic drugs. For efficacy, assessment still relies on careful documentation of changes in ictal activity as determined by seizure counts based on patients recall, direct clinical observation and (for absence seizures) EEG monitoring. In selected cases, assessment of seizure severity may also be indicated. The precise choice of outcome measures is largely dependent upon the specific trial design. In short term regulatory trials, parameters such as time to nth seizure after randomization (or after achievement of target dosage) may be used as an index of antiepileptic efficacy, but the clinical relevance of such measures is questionable. In add-on trials in refractory patients, changes, in seizure counts and proportion of patients achieving 50%, 75% and 100% reduction in seizure frequency may be appropriate. For long-term monotherapy trials in newly diagnosed patients, proportion of patients achieving prolonged remission (1-year or longer) usually represents the most clinically meaningful efficacy outcome. Retention of patients on the allocated treatment over time is also a valuable measure, but it should be regarded as a composite endpoint because decision to continue treatment is dependent on both efficacy and tolerability. At present, there is no universally accepted method for evaluating side effects, particularly those which can not be documented objectively. Spontaneous reports of symptoms or use of specific checklists have advantages and disadvantages. Studies aimed at ensuring greater standardization in safety assessment should be encouraged, especially with respect to need of obtaining quantitative estimates, and information on both prevalence and incidence of side effects should be reported in all trials. PMID- 9368922 TI - Outcome measures for the assessment of new antiepileptic drugs. AB - For the approval of any new medicinal product quality, safety and efficacy are essential requirements. This manuscript focuses on the clinical development programme. For the investigation of antiepileptic drugs some international guidelines are of special importance. They are based on the knowledge of many experts and can be seen as a consensus on minimal requirements; deviations must be thoroughly justified. In phases II and III, usually randomised, double-blind add-on studies versus placebo in patients with therapy-resistant seizures are used to get an impression of the efficacy and certain safety issues. A clear dose response relationship may be a good indication for efficacy. However, assessment of safety of the new product in add-on studies is difficult. Therefore comparative phase III monotherapy studies versus established antiepileptic drugs are essential to confirm the results obtained in add-on studies and are needed for a proper judgement of the efficacy/safety balance. The percentage of reduction of seizure frequency has played a dominating role as efficacy criterium. Nowadays preference is being given to the percentage responders. Which parameter is the most relevant for the given group of patients and what change is considered clinically relevant must be thoroughly argued. The definition of responder should focus on major benefit for the patients involved. PMID- 9368923 TI - Quality of life as an outcome measure for epilepsy clinical trials. AB - Assessment of health-related quality of life (HRQOL) has been developed to the point where well-validated instruments are being used in clinical trials. Data on the impact of new treatments can be used for formulary and regulatory decisions if the clinical trials are designed with appropriate instruments and sample sizes. However, more information is needed about the clinical significance of small differences in total or scale scores. Similarly, pharmacoeconomic studies should be prospective assessments that include evaluation of HRQOL as well as cost. In the future, these new aspects of outcome assessment are expected to be used as an adjunct to traditional seizure frequency and adverse effect reports in the selection of antiepileptic drugs. PMID- 9368924 TI - Discussion of the AED workshop. AB - An overview is given of the different issues that have been discussed, with subsequent recommendation. Standardisation of measurement and reporting of efficacy parameter and side-effects is essential; not only the number of patients achieving complete seizure controlled or have a decrease in seizure frequency and severity should be mentioned but also the number who dropped out and the reasons therefore. More information is needed on the teratogeneticy of a drug, either by performing control trials or by registration of all pregnancies with new anti epileptic drugs. Appropriate bio-marker for efficacy and toxicity should be developed. Health-related quality of life scales, collecting both subjective and objective information should be developed and used as complimentary tools in understanding more about the disease. A drug that improves the quality of life but is less effective in suppressing seizures should be marketed. Finally, pharmaco-economic studies should be encouraged in the field of epilepsy. PMID- 9368925 TI - Management of urinary tract infections: a comprehensive review. AB - Urinary tract infections (UTI) include a wide range of clinical entities. Starting from this situation, have been differentiated each of the UTI depending on location, age and sex, among other factors. Therefore, UTI have been classified and studied as follows: UTI in women, in men, in elderly people, in catheterized patients and in children. The different pharmacotherapeutic alternatives have been assessed and the classic agents compared with the most recent molecules. PMID- 9368926 TI - Determination of molecular weight of hyaluronic acid in bovine vitreous humour and Healon by high performance gel permeation chromatography and its depolymerization with ascorbic acid. AB - A method has been developed for the determination of the molecular weight of hyaluronic acid by high performance gel permeation chromatography. The molecular weight distribution was determined using three polymeric columns. Columns were calibrated using Pullulan Polymer molecular weight standards. The average molecular weight (+/- SD) of the hyaluronic acid in bovine vitreous humour and Healon were 1.20 x 10(6) Da (+/- 0.49 x 10(6) and 3.01 x 10(6) Da (+/- 0.14 x 10(6), respectively. Furthermore, the depolymerization of the hyaluronic acid in the presence of ascorbic acid (the concentration found in human eye) was studied. Samples incubated in the presence of atmospheric air showed more depolymerization than those where atmospheric air had been flushed-out with nitrogen. PMID- 9368927 TI - Calcium dobesilate-induced agranulocytosis. AB - Here we report a case of a patient in whom the administration of calcium dobesilate was associated with the development of an agranulocytosis episode. Eight weeks after the beginning of the treatment he was hospitalized with fever and leucopenia. Bone marrow biopsy showed a maturative promyelocytic interruption. All medication was withdrawn and blood cell count was completely recovered 7 days after admission. G-CSF was administered. A detailed study was performed and causal relationship was not suggestive for the other three drugs the patient was receiving. To date, there have only been reported two cases of calcium dobesilate induced agranulocytosis. PMID- 9368928 TI - Spatial frames of reference and somatosensory processing: a neuropsychological perspective. AB - In patients with lesions in the right hemisphere, frequently involving the posterior parietal regions, left-sided somatosensory (and visual and motor) deficits not only reflect a disorder of primary sensory processes, but also have a higher-order component related to a defective spatial representation of the body. This additional factor, related to right brain damage, is clinically relevant: contralesional hemianaesthesia (and hemianopia and hemiplegia) is more frequent in right brain-damaged patients than in patients with damage to the left side of the brain. Three main lines of investigation suggest the existence of this higher-order pathological factor. (i) Right brain-damaged patients with left hemineglect may show physiological evidence of preserved processing of somatosensory stimuli, of which they are not aware. Similar results have been obtained in the visual domain. (ii) Direction-specific vestibular, visual optokinetic and somatosensory or proprioceptive stimulations may displace spatial frames of reference in right brain-damaged patients with left hemineglect, reducing or increasing the extent of the patients' ipsilesional rightward directional error, and bring about similar directional effects in normal subjects. These stimulations, which may improve or worsen a number of manifestations of the neglect syndrome (such as extrapersonal and personal hemineglect), have similar effects on the severity of left somatosensory deficits (defective detection of tactile stimuli, position sense disorders). However, visuospatial hemineglect and the somatosensory deficits improved by these stimulations are independent, albeit related, disorders. (iii) The severity of left somatosensory deficits is affected by the spatial position of body segments, with reference to the midsagittal plane of the trunk. A general implication of these observations is that spatial (non-somatotopic) levels of representation contribute to corporeal awareness. The neural basis of these spatial frames includes the posterior parietal and the premotor frontal regions. These spatial representations could provide perceptual-premotor interfaces for the organization of movements (e.g. pointing, locomotion) directed towards targets in personal and extrapersonal space. In line with this view, there is evidence that the sensory stimulations that modulate left somatosensory deficits affect left motor disorders in a similar, direction-specific, fashion. PMID- 9368929 TI - Spatial orientation and the representation of space with parietal lobe lesions. AB - Damage to the human parietal cortex leads to disturbances of spatial perception and of motor behaviour. Within the parietal lobe, lesions of the superior and of the inferior lobule induce quite different, characteristic deficits. Patients with inferior (predominantly right) parietal lobe lesions fail to explore the contralesional part of space by eye or limb movements (spatial neglect). In contrast, superior parietal lobe lesions lead to specific impairments of goal directed movements (optic ataxia). The observations reported in this paper support the view of dissociated functions represented in the inferior and the superior lobule of the human parietal cortex. They suggest that a spatial reference frame for exploratory behaviour is disturbed in patients with neglect. Data from these patients' visual search argue that their failure to explore the contralesional side is due to a disturbed input transformation leading to a deviation of egocentric space representation to the ipsilesional side. Data further show that this deviation follows a rotation around the earth-vertical body axis to the ipsilesional side rather than a translation towards that side. The results are in clear contrast to explanations that assume a lateral gradient ranging from a minimum of exploration in the extreme contralesional to a maximum in the extreme ipsilesional hemispace. Moreover, the failure to orient towards and to explore the contralesional part of space appears to be distinct from those deficits observed once an object of interest has been located and releases reaching. Although patients with neglect exhibit a severe bias of exploratory movements, their hand trajectories to targets in peripersonal space may follow a straight path. This result suggests that (i) exploratory and (ii) goal-directed behaviour in space do not share the same neural control mechanisms. Neural representation of space in the inferior parietal lobule seems to serve as a matrix for spatial exploration and for orienting in space but not for visuomotor processes involved in reaching for objects. Disturbances of such processes rather appear to be prominent in patients with more superior parietal lobe lesions and optic ataxia. PMID- 9368930 TI - Multimodal integration for the representation of space in the posterior parietal cortex. AB - The posterior parietal cortex has long been considered an 'association' area that combines information from different sensory modalities to form a cognitive representation of space. However, until recently little has been known about the neural mechanisms responsible for this important cognitive process. Recent experiments from the author's laboratory indicate that visual, somatosensory, auditory and vestibular signals are combined in areas LIP and 7a of the posterior parietal cortex. The integration of these signals can represent the locations of stimuli with respect to the observer and within the environment. Area MSTd combines visual motion signals, similar to those generated during an observer's movement through the environment, with eye-movement and vestibular signals. This integration appears to play a role in specifying the path on which the observer is moving. All three cortical areas combine different modalities into common spatial frames by using a gain-field mechanism. The spatial representations in areas LIP and 7a appear to be important for specifying the locations of targets for actions such as eye movements or reaching; the spatial representation within area MSTd appears to be important for navigation and the perceptual stability of motion signals. PMID- 9368931 TI - From visual affordances in monkey parietal cortex to hippocampo-parietal interactions underlying rat navigation. AB - This paper explores the hypothesis that various subregions (but by no means all) of the posterior parietal cortex are specialized to process visual information to extract a variety of affordances for behaviour. Two biologically based models of regions of the posterior parietal cortex of the monkey are introduced. The model of the lateral intraparietal area (LIP) emphasizes its roles in dynamic remapping of the representation of targets during a double saccade task, and in combining stored, updated input with current visual input. The model of the anterior intraparietal area (AIP) addresses parietal-premotor interactions involved in grasping, and analyses the interaction between the AIP and premotor area F5. The model represents the role of other intraparietal areas working in concert with the inferotemporal cortex as well as with corollary discharge from F5 to provide and augment the affordance information in the AIP, and suggests how various constraints may resolve the action opportunities provided by multiple affordances. Finally, a systems-level model of hippocampo parietal interactions underlying rat navigation is developed, motivated by the monkey data used in developing the above two models as well as by data on neurones in the posterior parietal cortex of the monkey that are sensitive to visual motion. The formal similarity between dynamic remapping (primate saccades) and path integration (rat navigation) is noted, and certain available data on rat posterior parietal cortex in terms of affordances for locomotion are explained. The utility of further modelling, linking the World Graph model of cognitive maps for motivated behaviour with hippocampal-parietal interactions involved in navigation, is also suggested. These models demonstrate that posterior parietal cortex is not only itself a network of interacting subsystems, but functions through cooperative computation with many other brain regions. PMID- 9368932 TI - Parietal and hippocampal contribution to topokinetic and topographic memory. AB - This paper reviews the involvement of the parietal cortex and the hippocampus in three kinds of spatial memory tasks which all require a memory of a previously experienced movement in space. The first task compared, by means of positron emission tomography (PET) scan techniques, the production, in darkness, of self paced saccades (SAC) with the reproduction, in darkness, of a previously learned sequence of saccades to visual targets (SEQ). The results show that a bilateral increase of activity was seen in the depth of the intraparietal sulcus and the medial superior parietal cortex (superior parietal gyrus and precuneus) together with the frontal sulcus but only in the SEQ task, which involved memory of the previously seen targets and possibly also motor memory. The second task is the vestibular memory contingent task, which requires that the subject makes, in darkness, a saccade to the remembered position of a visual target after a passively imposed whole-body rotation. Deficits in this task, which involves vestibular memory, were found predominantly in patients with focal vascular lesions in the parieto-insular (vestibular) cortex, the supplementary motor area supplementary eye field area, and the prefrontal cortex. The third task requires mental navigation from the memory of a previously learned route in a real environment (the city of Orsay in France). A PET scan study has revealed that when subjects were asked to remember visual landmarks there was a bilateral activation of the middle hippocampal regions, left inferior temporal gyrus, left hippocampal regions, precentral gyrus and posterior cingulate gyrus. If the subjects were asked to remember the route, and their movements along this route, bilateral activation of the dorsolateral cortex, posterior hippocampal areas, posterior cingulate gyrus, supplementary motor areas, right middle hippocampal areas, left precuneus, middle occipital gyrus, fusiform gyrus and lateral premotor area was found. Subtraction between the two conditions reduced the activated areas to the left hippocampus, precuneus and insula. These data suggest that the hippocampus and parietal cortex are both involved in the dynamic aspects of spatial memory, for which the name 'topokinetic memory' is proposed. These dynamic aspects could both overlap and be different from those involved in the cartographic and static aspects of 'topographic' memory. PMID- 9368933 TI - A new view of hemineglect based on the response properties of parietal neurones. AB - Lesion studies of the parietal cortex have led to a wide range of conclusions regarding the coordinate reference frame in which hemineglect is expressed. A model of spatial representation in the parietal cortex has recently been developed in which the position of an object is not encoded in a particular frame of reference, but instead involves neurones computing basis functions of sensory inputs. In this type of representation, a nonlinear sensorimotor transformation of an object is represented in a population of units having the response properties of neurones that are observed in the parietal cortex. A simulated lesion in a basis-function representation was found to replicate three of the most important aspects of hemineglect: (i) the model behaved like parietal patients in line-cancellation and line-bisection experiments; (ii) the deficit affected multiple frames of reference; and (iii) the deficit could be object centred. These results support the basis-function hypothesis for spatial representations and provide a testable computational theory of hemineglect at the level of single cells. PMID- 9368934 TI - Hierarchical organization of cognitive memory. AB - This paper addresses the question of the organization of memory processes within the medial temporal lobe. Evidence obtained in patients with late-onset amnesia resulting from medial temporal pathology has given rise to two opposing interpretations of the effects of such damage on long-term cognitive memory. One view is that cognitive memory, including memory for both facts and events, is served in a unitary manner by the hippocampus and its surrounding cortices; the other is that the basic function affected in amnesia is event memory, the memory for factual material often showing substantial preservation. Recent findings in patients with amnesia resulting from relatively selective hippocampal damage sustained early in life suggest a possible reconciliation of the two views. The new findings suggest that the hippocampus may be especially important for event as opposed to fact memory, with the surrounding cortical areas contributing to both. Evidence from neuroanatomical and neurobehavioural studies in monkeys is presented in support of this proposal. PMID- 9368935 TI - Right medial temporal-lobe contribution to object-location memory. AB - An important aspect of normal human memory, and one humans share with many other species, is the ability to remember the location of objects in their environment. There is by now strong evidence from the study of epileptic patients undergoing brain surgery that right temporal-lobe lesions that encroach extensively upon the hippocampal and parahippocampal gyrus impair the delayed, but not the immediate, recall of the location of objects within a random array. These findings have now been extended to a multiple-trial, spatial-array learning task; by including not only patients tested after unilateral anterior temporal lobectomy but also those with a selective left or right amygdalohippocampectomy, it has been shown that the deficits associated with right hippocampal lesions are not dependent upon conjoint damage to the lateral temporal neocortex. Furthermore, the fact that on the learning task no group differences were seen on Trial 1, at zero delay, strengthened the view that the impairment was in the maintenance and subsequent retrieval of information rather than in its initial encoding. These results left unresolved the question of whether the deficit was in the mediation of object place associations or whether it could be reduced to a more general impairment in memory for location as such. Also left unanswered was the neuroanatomical question as to the relative contributions of the hippocampus and the parahippocampal gyrus to the performance of the experimental tasks. These questions were addressed in two blood-flow activation studies that made use of positron emission tomography (PET) and magnetic resonance imaging (MRI) and incorporated computerized versions of object-location and simple-location memory tasks. Taken together, the results point to a special contribution from the anterior part of the right parahippocampal gyrus, probably corresponding to the entorhinal cortex, to the retrieval of object-place associations, a result consonant with neurophysiological findings in non-human primates. PMID- 9368936 TI - Hippocampal involvement in human topographical memory: evidence from functional imaging. AB - Functional brain imaging in humans is beginning to reveal a network of brain regions that subserve topographical learning: the medial parietal lobe, the posterior cingulate gyrus, occipitotemporal areas, the parahippocampal gyrus and the right hippocampus. These findings illuminate the patient lesion literature where all of these brain regions have been implicated at one time or another in cases of topographical disorientation. Once topographical information is acquired, the neuroanatomy that supports its use from either episodic or semantic memory is similar to that activated during encoding. The specific contributions of extrahippocampal regions within the topographical memory system are being revealed, such as the role of the right parahippocampal gyrus in object-in-place encoding. The right hippocampus is clearly involved in processing spatial layouts over long as well as short time-courses, and participates in both the encoding and the retrieval of topographical memory. The ventromedial orbitofrontal cortex is recruited when information in the topographical memory system is not sufficient to produce direct navigation to a goal place. PMID- 9368937 TI - Amnesia and neglect: beyond the Delay-Brion system and the Hebb synapse. AB - Hippocampal damage in people causes impairments of episodic memory, but in rats it causes impairments of spatial learning. Experiments in macaque monkeys show that these two kinds of impairment are functionally similar to each other. After any lesion that interrupts the Delay-Brion system (hippocampus, fornix, mamillary bodies and anterior thalamus) monkeys are impaired in scene-specific memory, where an event takes place against a background that is specific to that event. Scene-specific memory in the monkey corresponds to human episodic memory, which is the memory of a unique event set in a particular scene, as opposed to scene independent human knowledge, which is abstracted from many different scenes. However, interruption of the Delay-Brion system is not sufficient to explain all of the memory impairments that are seen in amnesic patients. To explain amnesia the specialized function of the hippocampus in scene memory needs to be considered alongside the other, qualitatively different functional specializations of other memory systems of the temporal lobe, including the perirhinal cortex and the amygdala. In all these specialized areas, however, including the hippocampus, there is no fundamental distinction between memory systems and perceptual systems. In explaining memory disorders in amnesia it is also important to consider them alongside the memory disorders of neglect patients. Neglect patients fail to represent in memory the side of the world that is contralateral to the current fixation point, in both short- and long-term memory retrieval. Neglect was produced experimentally by unilateral visual disconnection in the monkey, confirming the idea that visual memory retrieval is retinotopically organized; patients with unilateral medial temporal-lobe removals showed lateralized memory impairments for half-scenes in the visual hemifield contralateral to the removal. Thus, in scene-memory retrieval the Delay-Brion system contributes to the retrieval of visual memories into the retinotopically organized visual cortex. This scene memory interpretation of hippocampal function needs to be contrasted with the cognitive-map hypothesis. The cognitive-map model of hippocampal function shares some common assumptions with the Hebb-synapse model of association formation, and the Hebb-synapse model can be rejected on the basis of recent evidence that monkeys can form direct associations in memory between temporally discontiguous events. Our general conclusion is that the primate brain encompasses widespread and powerful memory mechanisms which will continue to be poorly understood if theory and experimentation continue to concentrate too much, as they have in the past, on the hippocampus and the Hebb synapse. PMID- 9368938 TI - Hippocampal synaptic plasticity: role in spatial learning or the automatic recording of attended experience? AB - Allocentric spatial learning can sometimes occur in one trial. The incorporation of information into a spatial representation may, therefore, obey a one-trial correlational learning rule rather than a multi-trial error-correcting rule. It has been suggested that physiological implementation of such a rule could be mediated by N-methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP) in the hippocampus, as its induction obeys a correlational type of synaptic learning rule. Support for this idea came originally from the finding that intracerebral infusion of the NMDA antagonist AP5 impairs spatial learning, but studies summarized in the first part of this paper have called it into question. First, rats previously given experience of spatial learning in a watermaze can learn a new spatial reference memory task at a normal rate despite an appreciable NMDA receptor blockade. Second, the classical phenomenon of 'blocking' occurs in spatial learning. The latter finding implies that spatial learning can also be sensitive to an animal's expectations about reward and so depend on more than the detection of simple spatial correlations. In this paper a new hypothesis is proposed about the function of hippocampal LTP. This hypothesis retains the idea that LTP subserves rapid one-trial memory, but abandons the notion that it serves any specific role in the geometric aspects of spatial learning. It is suggested that LTP participates in the automatic recording of attended experience': a subsystem of episodic memory in which events are temporarily remembered in association with the contexts in which they occur. An automatic correlational form of synaptic plasticity is ideally suited to the online registration of context event associations. In support, it is reported that the ability of rats to remember the most recent place they have visited in a familiar environment is exquisitely sensitive to AP5 in a delay-dependent manner. Moreover, new studies of the lasting persistence of NMDA-dependent LTP, known to require protein synthesis, point to intracellular mechanisms that enable transient synaptic changes to be stabilized if they occur in close temporal proximity to important events. This new property of hippocampal LTP is a desirable characteristic of an event memory system. PMID- 9368939 TI - Variable place-cell coupling to a continuously viewed stimulus: evidence that the hippocampus acts as a perceptual system. AB - A key feature of perception is that the interpretation of a single, continuously available stimulus can change from time to time. This aspect of perception is well illustrated by the use of ambiguous figures that can be seen in two different ways. When people view such a stimulus they almost universally describe what they are seeing as jumping between two states. If it is agreed that this perceptual phenomenon is causally linked to the activity of nerve cells, the state jumps would have to occur in conjunction with changes in neural activity somewhere in the nervous system. Our experiments suggest that hippocampal place cells are part of a perceptual system. We conducted variations of a 'cue-card rotation' experiment on rats in which the angular position of a prominent visual stimulus on the wall of cylinder is changed in the rat's presence. The three main results are that (i) place-cell firing fields remain stationary if the cue is rotated by 180 degrees, so the relation between the cue and the field is altered; (ii) firing fields rotate by 45 degrees when the cue is rotated by 45 degrees, so the relation between the field and the card is maintained; and (iii) if the cue is first rotated by 180 degrees and then rotated in a series of 45 degrees steps, the field winds up at a different angular position relative to the card when the card is back in its original position. Thus, place cells can fire in two different ways in response to a continuously viewed stimulus. We conclude that place cells reveal that the hippocampal mapping system also has properties expected of a perceptual system. PMID- 9368940 TI - Dissociation of exteroceptive and idiothetic orientation cues: effect on hippocampal place cells and place navigation. AB - Navigation by means of cognitive maps appears to require the hippocampus; hippocampal place cells (PCs) appear to store spatial memories because their discharge is confined to cell-specific places called firing fields (FFs). Experiments with rats manipulated idiothetic and landmark-related information to understand the relationship between PC activity and spatial cognition. Rotating a circular arena in the light caused a discrepancy between these cues. This discrepancy caused most FFs to disappear in both the arena and room reference frames. However, FFs persisted in the rotating arena frame when the discrepancy was reduced by darkness or by a card in the arena. The discrepancy was increased by 'field clamping' the rat in a room-defined FF location by rotations that countered its locomotion. Most FFs dissipated and reappeared an hour or more after the clamp. Place-avoidance experiments showed that navigation uses independent idiothetic and exteroceptive memories. Rats learned to avoid the unmarked footshock region within a circular arena. When acquired on the stable arena in the light, the location of the punishment was learned by using both room and idiothetic cues; extinction in the dark transferred to the following session in the light. If, however, extinction occurred during rotation, only the arena frame avoidance was extinguished in darkness; the room-defined location was avoided when the lights were turned back on. Idiothetic memory of room-defined avoidance was not formed during rotation in light; regardless of rotation, there was no avoidance when the lights were turned off, but room-frame avoidance reappeared when the lights were turned back on. The place-preference task rewarded visits to an allocentric target location with a randomly dispersed pellet. The resulting behaviour alternated between random pellet searching and target-directed navigation, making it possible to examine PC correlates of these two classes of spatial behaviour. The independence of idiothetic and exteroceptive spatial memories and the disruption of PC firing during rotation suggest that PCs may not be necessary for spatial cognition; this idea can be tested by recordings during the place-avoidance and preference tasks. PMID- 9368941 TI - Memory reprocessing in corticocortical and hippocampocortical neuronal ensembles. AB - Hippocampal cells that fire together during behaviour exhibit enhanced activity correlations during subsequent sleep, with some preservation of temporal order information. Thus, information reflecting experiences during behaviour is re expressed in hippocampal circuits during subsequent 'offline' periods, as postulated by some theories of memory consolidation. If the hippocampus orchestrates the reinstatement of experience-specific activity patterns in the neocortex, as also postulated by such theories, then correlation patterns both within the neocortex and between hippocampus and neocortex should also re-emerge during sleep. Ensemble recordings were made in the posterior parietal neocortex, in CA1, and simultaneously in both areas, in seven rats. Each session involved an initial sleep episode (S1), behaviour on a simple maze (M), and subsequent sleep (S2). The ensemble activity-correlation structure within and between areas during S2 resembled that of M more closely than did the correlation pattern of S1. Temporal order (i.e. the asymmetry of the cross-correlogram) was also preserved within, but not between, structures. Thus, traces of recent experience are re expressed in both hippocampal and neocortical circuits during sleep, and the representations in the two areas tend to correspond to the same experience. The poorer preservation of temporal firing biases between neurons in the different regions may reflect the less direct synaptic coupling between regions than within them. Alternatively, it could result from a shift, between behavioural states, in the relative dominance relations in the corticohippocampal dialogue. Between structure order will be disrupted, for example, if, during behaviour, neocortical patterns tend to drive corresponding hippocampal patterns, whereas during sleep the reverse occurs. This possibility remains to be investigated. PMID- 9368942 TI - Robotic and neuronal simulation of the hippocampus and rat navigation. AB - The properties of hippocampal place cells are reviewed, with particular attention to the nature of the internal and external signals that support their firing. A neuronal simulation of the firing of place cells in open-field environments of varying shape is presented. This simulation is coupled with an existing model of how place-cell firing can be used to drive navigation, and is tested by implementation as a miniature mobile robot. The sensors on the robot provide visual, odometric and short-range proximity data, which are combined to estimate the distance of the walls of the enclosure from the robot and the robot's current heading direction. These inputs drive the hippocampal simulation, in which the robot's location is represented as the firing of place cells. If a goal location is encountered, learning occurs in connections from the concurrently active place cells to a set of 'goal cells', which guide subsequent navigation, allowing the robot to return to an unmarked location. The system shows good agreement with actual place-cell firing, and makes predictions regarding the firing of cells in the subiculum, the effect of blocking long-term synaptic changes, and the locus of search of rats after deformation of their environment. PMID- 9368943 TI - Trends in conceptions before and after the 1995 pill scare. AB - On 18 October 1995, the Committee on Safety of Medicines issued a warning that seven brands of the contraceptive pill (containing 'new generation' progestogens) carried a relatively higher risk of thrombosis (the formation of a blood clot in a vein). This warning received much attention from the media. Family planning services and others working in public health raised concerns that the pill scare would result in an increase in unplanned pregnancies. This article uses national conception statistics to show trends before and after October 1995. PMID- 9368944 TI - Spouses with identical residential addresses before marriage: an indicator of pre marital cohabitation. AB - This article analyses new data on identical address marriages in England and Wales during 1994. It outlines previous background research which has provided good evidence that identical address marriages are likely to be ones in which the couple premaritally cohabited. Recent evidence, based on results from the General Household Survey, is also presented. The article analyses the number and characteristics of identical address marriages, both to provide new (proxy) information on pre-marital cohabitation, and also to announce the publication of a new set of tables on identical address marriages which will be included in the Marriage and Divorce Statistics annual reference volume in future years. Overall, six in every 10 couples marrying in 1994 gave identical addresses. The pattern of variation of this proportion among different subgroups of couples who married in 1994 is analysed--according to: age at marriage; the previous marital status of the partners before marriage; the manner of solemnisation of the marriage, and, for religious weddings, by denomination; by day of the week; month of the year, and by the county in which the wedding took place. PMID- 9368945 TI - An overview of the population in Europe and North America. AB - This article is based on information from Trends in Europe, the statistical yearbook of the Economic Commission for Europe. It highlights some of the key population and health statistics for member countries, using the most recent data available--generally for 1995--collected from a wide range of national and international sources. PMID- 9368946 TI - The re-based 1991 population estimates by marital status. AB - Shortly after preparing the re-based 1991 population estimates, the Office for National Statistics produced provisional population estimates by legal marital status (for England and Wales as a whole). These provisional estimates were calculated using a marital status distribution for 1991 that was updated from the 1981 Census. These estimates have now been revised to incorporate marital status information from the 1991 Census. This article outlines the options for re-basing the estimates, the method used, and assesses the effect of the revision on the rates of marriage, divorce and mortality by single year of age. The main differences between the provisional and final re-based estimates in 1991 are: estimates of widowed men and women are 7 per cent and 2 per cent higher, respectively, estimates of divorced men and women are 2 per cent and 3 per cent lower, re-marriage rates (amongst the divorced or widowed) for men 50-59 increased, and mortality rates for single and divorced men increased for those aged over 70. PMID- 9368947 TI - The ESRC review of government social classifications. AB - In this article we first discuss the background to the ESRC Review of Government Social Classifications and the recommendations of the Review Committee's initial report to the Office for National Statistics in 1995. Second, we discuss the work of Phase 2 of the review, including the derivation of an interim version of a proposed revised government social classification schema and the criterion and construct validation work so far undertaken using this schema. Finally, we indicate the further work required to establish the schema in its ultimate recommended form for use by ONS and others. The main purpose of the paper is to introduce users of government social classifications both to the ideas underlying the review and to the revised version of the current classifications which we shall be recommending to ONS. PMID- 9368948 TI - Influence of short-term water deprivation on antipyrine disposition in calves. AB - The effect of four days water deprivation on the metabolism of antipyrine was studied in female Holstein-Friesian calves, aged 24 to 25 days, by measuring the antipyrine plasma clearance and the excretion of three major metabolites of antipyrine in urine. Water deprivation was associated with a statistically significant (P < 0.01) increase in the plasma antipyrine elimination half-life from 10.85(1.14) hours to 14.00(1.05) hours. In water deprived calves the systemic clearance of antipyrine was significantly (P < 0.05) decreased from 0.75(0.07) ml min-1 kg-1 to 0.56(0.05) ml min-1 kg-1. The excretion of three major metabolites of antipyrine: 4-hydroxyantipyrine, 3-hydroxymethylantipyrine and norantipyrine in urine was significantly (P < 0.01) decreased after water deprivation. In the control group no significant differences between the pharmacokinetic parameters of antipyrine in 24 to 25 and 28 to 29 day-old calves were observed. Also urinary profiles of antipyrine in calves from the control group did not differ significantly between 24 to 25 and 28 to 29 days of life. Our data indicate that water deprivation inhibits antipyrine elimination in calves. PMID- 9368949 TI - Serological assays for the identification of Oesophagostomum dentatum infections in pigs. AB - Oesophagostomum dentatum antigen preparations of third (L3) or fourth (L4) stage larvae were characterised by Western blotting. Panels of sera obtained from pigs infected with O dentatum and Ascaris suum, respectively, reacted with the same bands of L3 antigen. In contrast high specificity against a characteristic band, was observed when L4 extract was employed as antigen. To establish an enzyme linked immunosorbent assay (ELISA), a panel of homologous and heterologous sera was tested against O dentatum L4 extract. The best combined specificity and sensitivity was obtained when horseradish peroxidase (HRP) goat anti swine IgG conjugate was used rather than HRP rabbit anti swine Ig conjugate. Testing series of sera from pigs infected with single doses of either 2000, 20,000 or 200,000 infective larvae by the ELISA, a significant dose dependency in the antibody response was observed between the low and high dosage groups. This assay may be useful in future studies of the immune-mechanisms against nodular worm infections in pigs. PMID- 9368950 TI - Tetracycline derivatives inhibit cartilage degradation in cultured embryonic chick tibiae. AB - Tetracyclines have been used extensively as antibiotics and growth promoters in the poultry industry. However, they can inhibit angiogenesis and matrix degradation, both of which are essential for normal growth plate cartilage development. The purpose of this research was to test the ability of several tetracyclines to inhibit cartilage degradation in cultured embryonic chick tibiae. Based on gross observations and biochemical quantitation of collagen release into the media, minocycline, doxycycline, oxytetracycline, and tetracycline inhibited cartilage degradation at 20, 40, 60, and 80 micrograms ml 1 respectively. Chlortetracycline did not inhibit cartilage degradation at concentrations tested. The ability of the tetracycline derivative to inhibit cartilage degradation was in general related to its hydrophobicity. Since a majority of the cartilage in the embryonic chick tibia will develop into the post hatched growth plate, it may be important to determine if any of the tetracyclines used as antibiotics could cause problems in in vivo growth plate cartilage development. PMID- 9368951 TI - Longitudinal studies of reproducibility and variability of indirect (oscillometric) blood pressure measurements in dogs: evidence for tracking. AB - To be clinically reliable, blood pressure readings taken in quiet surroundings with good technique from healthy, unstressed subjects accustomed to the procedure, should be reasonably constant between occasions. Apart from changes attributable to age or stress, sustained rises suggest hypertension. Yet it is increasingly realised that arterial pressure shows great short-term lability. Despite this, 'tracking' occurs in groups of humans, i.e. when ranked by blood pressure they tend to maintain their rank order. This paper examines month-on month variability of arterial pressure, measured by non-invasive oscillometry (Dinamap) in both pet dogs and kennel populations. 'Tracking' occurred and there was also evidence of 'white coat' effects. Heart rate was more variable than arterial pressure and should not be used to reject pressure readings unless changes are extreme. There was further evidence that canine blood pressure rises with age. PMID- 9368952 TI - Pharmacokinetics of von Willebrand factor and factor VIII in canine von Willebrand disease and haemophilia A. AB - The pharmacokinetics of von Willebrand factor antigen (vWf:Ag) and factor VIII coagulant (FVIII:C) activity in dogs with von Willebrand Disease (vWD) and haemophilia A, respectively, were assessed after the administration of fresh frozen plasma (FFP) and cryoprecipitate. Loading doses necessary to attain target plasma concentrations of each factor were estimated to be 63 U kg-1 BW for FFP and 13 U kg-1 BW for cryoprecipitate to reach 35 U dl-1 vWf:Ag in vWD and 23 U kg 1 BW for FFP and 4 U kg-1 BW for cryoprecipitate to reach 30 U dl-1 FVIII:C in haemophilia A. The estimated volumes of FFP required to attain these target concentrations (49 ml kg-1 BW for vWD and 20 ml kg-1 BW for haemophilia A) are approximately 10-fold higher than the volumes of cryoprecipitate required (4 ml kg-1 BW for vWD and 2 ml kg-1 BW for haemophilia A). This indicates that cryoprecipitate is a more efficient and practical means of treating or preventing haemorrhage in these two haemostatic disorders. PMID- 9368953 TI - Degenerative joint disease in poultry--differences in composition and morphology of articular cartilage are associated with strain susceptibility. AB - The morphology and basic biochemical composition of articular cartilage from two strains of fowl were examined. Broiler breeder fowl are considered susceptible to degenerative joint disease (DJD); histological examination of one-year-old broiler breeders showed in some samples, articular cartilage thinning, fibrillation and chondrocyte cluster formation, features considered typical of DJD. Examination of similar samples from laying strain fowl showed only minor age related changes such as some slight cartilage thinning and very mild fibrillation. The articular cartilage from the broiler breeder birds was significantly more hydrated with a higher uronic acid content than that of the laying strain birds. In addition, unloaded articular surfaces such as the proximal humerus had significantly higher amounts of uronic acid than the loaded cartilage surfaces of the proximal tarsometatarsus and the distal tibiotarsus; this suggested that the joint loading may have a role in any biochemical differences found between joints and between strains of fowl. These findings concur with other reports in mammals that showed increased hydration and uronic acid in association with early DJD and in models of osteoarthritis (OA). Thus, despite some differences between avian and mammalian articular cartilage, studies on avian DJD may give insights into mammalian disease. PMID- 9368954 TI - The influence of lifestyle and diet on the lipoprotein profile of border collies. AB - Plasma lipoprotein cholesterol and triglycerides were determined in two groups of Border Collies, one actively working and the other pets. Baseline concentrations of total, low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol were higher, and HDL triglyceride concentrations lower in the pet dogs. Lifestyle of the dogs was assessed by questionnaire completed by the owners. Measurement of exercise was made by visual observation and using a Caltrac activity monitor. The working dogs were a homogenous group with respect to lifestyle and diet, but the pet dogs showed differences in lipoprotein profile relating to housing, dietary fat and exercise intensity. Two diets with different levels of dietary fat (13 and 20 per cent dry weight) were given for two months each. After two months on either of the diets the cholesterol concentration of the working dogs increased and HDL triglyceride concentration decreased, and there were no significant differences between the groups, but very low density lipoprotein (VLDL) triglyceride increased significantly in the less active pet dogs. PMID- 9368955 TI - Ovine squamous cell carcinoma: immunocharacterisation of neoplastic cells and peritumoural cellular infiltrate. AB - An immunohistochemical characterisation of neoplastic cells and peritumoural cellular infiltrate of ovine squamous cell carcinomas (OSCC) in different stages of growth was carried out using a commercially-available panel of seven antibodies, and formalin-fixed and paraffin-embedded tissue samples. Neoplastic cells reacted with the anti-keratin monoclonal antibody RCK-102 and with an anti keratin polyclonal antibody, whereas they were unreactive with the anti-keratin monoclonal antibody NCL-5D3. The tumour cells were unreactive with the anti vimentin polyclonal antibody. Increased numbers of CD3+ T-lymphocytes, IgG containing plasma cells and lysozyme+ macrophages were associated with precancerous lesions (actinic keratosis) and with early OSCC. These results show that early lesions of OSCC induce an in situ cellular and humoral immune response. In advanced OSCC, the number of CD3+ T-lymphocytes and macrophages in the peri- and intratumoural cellular infiltrate remained high, whereas a significant decrease of IgG-containing plasma cells was found compared with early OSCC. This finding suggests an in situ decrease in the humoral immune response in advanced OSCC. PMID- 9368956 TI - Transmission electron microscopy of the epithelium of distal airways and pulmonary parenchyma of the goat lung. AB - Lungs from eight goats of mixed sexes and breeds (Cashmere, Nubian and Toggenburg) aged between 10 and 48 months were used in this study. Tissues from lung parenchyma were minced and routinely prepared for transmission electron microscopy (TEM) after using different methods of fixation. Thick sections were examined with a light microscope and samples, to include terminal bronchioles, respiratory bronchioles, alveolar ducts and alveolar membrane, were selected for ultrathin sectioning. Six cell types, ciliated, non-ciliated bronchiolar epithelial, mucus-producing, alveolar Type I, alveolar Type II and capillary endothelial cell were identified and characterised cytologically. It was established that the cell population in the distal airways is similar to that observed in other domestic mammals. The mucus-producing cell, which appears to be a common cell type in the distal airways of man and Rhesus monkey, was encountered particularly in adult goats in the present study. This study has also established that the Clara cell of the goat shows some cytological differences from those of some other mammalian species by having a large amount of SER, particularly in the apical region. Lipid vacuoles were seen to be a feature of the alveolar Type II cells; these do not appear to have been reported in other mammalian species. The study has provided a basic understanding of the morphological features of the cell population of the epithelium lining the distal airways in the goat's respiratory tract. The difference in junctional complexes between the various alveolar epithelial cells perhaps signify a different pattern of intercellular transport, thus influencing the pathogenesis and resolution of alveolar pulmonary edema. PMID- 9368957 TI - Antibody response after treatment in cattle infected with Psoroptes ovis. AB - The decline of anti-Psoroptes ovis antibody titres after treatment was studied in six groups of naturally infected cattle. In all trials, using a limiting dilution technique, the specific antibody levels were assessed by ELISA on sera collected at regular intervals up to 78 days post treatment. All individual antibody titres started to decline between day 7 and day 14 post treatment. A linear decrease was observed. In a limited trial, five experimentally infected animals were bled monthly after treatment and seronegativity was reached within four months. The results obtained were in agreement with those obtained in the five field trials. Using a linear regression model, it was estimated by interpolation that most of the animals would have been seronegative within seven months post treatment. These results suggest that the exposure to specific P ovis antigen stops with the end of parasite activity and that dead mites are relatively non-immunogenic. PMID- 9368958 TI - The ameliorating effect of Yucca schidigera extract on canine and feline faecal aroma. AB - Addition of Yucca schidigera extract (YSE) products to canine or feline diets improved the character and reduced the intensity of faecal aroma as monitored by a human panel. The general condition of the animals was not adversely affected as monitored by faecal pH, food retention time, and blood cell counts. Blood urea increased significantly in YSE-treated cats, possibly due to the saponins of YSE affecting gut wall permeability. This finding contrasts with previously published reports of a reduction in blood urea on the addition of sarsaponin (from YSE) to rat diets and of YSE products to poultry and cattle diets. PMID- 9368959 TI - The effect of Yucca schidigera extract on canine and feline faecal volatiles occurring concurrently with faecal aroma amelioration. AB - Addition of Yucca schidigera extract (YSE) products to canine or feline diets improved faecal aroma as monitored by a human panel. Odour port-gas chromatography (GC) indicated different odour component types in dog faecal volatiles and, in particular, 'faecal'-type odours due to methyl sulfides. GC mass spectrometry demonstrated several chemical compound classes present in faecal volatiles and quantitation in the cat indicated apparently significant changes in the concentrations of several compounds on YSE treatment, although these were not necessarily aroma components. The potential for direct YSE alteration of aroma perception in a mixture of volatiles, possibly by binding, was demonstrated. PMID- 9368960 TI - Inhibition of xylazine induced uterine contractility by clenbuterol and nifedipine. AB - A study was undertaken in order to determine the effects of xylazine on uterine contractility in goats premedicated with clenbuterol or nifedipine. These drugs inhibit uterine activity by acting as potent tocolytic or uterine relaxant agents. A balloon-tipped catheter was inserted under sedation and local anaesthesia on to a uterine horn in 15 cycling goats in order to record intrauterine pressure changes. Three groups of five goats were used: group I was treated with an intravenous dose of 0.1 mg kg-1 of xylazine. Groups II and III were pretreated with 4 micrograms kg-1 of clenbuterol and 80 micrograms kg-1 of nifedipine, respectively, before administrating the same dose of zylazine. Xylazine increased the frequency and intensity of uterine contractions significantly and the value of the area under the contraction curves was significantly higher than that observed under basal conditions i.e. before drug treatment. In goats premedicated with clenbuterol or nifedipine, the uterotonic effects of xylazine (2858 +/- 217 versus basal contractility: 1241 +/- 173 mm2.5 min-1, P < 0.05) were inhibited for the 30 minutes recording period. These data indicate that clenbuterol and nifedipine can be used as potent tocolytic agents in order to prevent the uterine side effects of xylazine. PMID- 9368961 TI - In vitro isolation and characterisation of a bovine Neospora species in Japan. AB - Eleven aborted bovine fetuses and five calves suspected as having neosporosis were necropsied and tissues from these animals were inoculated into bovine cardiopulmonary aortic endothelial cells and monkey kidney cells and maintained at 37 degrees C with 5 per cent CO2. Neospora tachyzoites were observed in one cell 49 days after inoculation. The isolated parasite (JPA1) was morphologically identical to the previously reported bovine Neospora species (BPA1) and confirmed by its strong antigenic reactivity with bovine control antisera to Neospora species and its lack of reactivity with Toxoplasma gondii and Sarcocystis cruzi antisera. This is the first bovine Neospora species isolate in Asia and further studies with this isolate are now expected. PMID- 9368962 TI - Some chickens which are viraemic with subgroup J avian leukosis virus have antibody-forming cells but no circulating antibody. AB - New immunoperoxidase-based assays for splenic IgG -antibody-forming cells (AFC) and serum IgG-antibody were used to look for antibody to HPRS-103 in meat-type birds. Meat type birds are known to be less likely to produce neutralising antibody and to be less likely to clear virus from their serum than layer-type birds after infection at hatch. In this work all 12 of the brown leghorn layer type birds and 5/12 of the line 21 meat-type birds had produced AFC and serum antibody and had cleared serum virus at 63, 82 and 110 days of age. None of the seven viraemic line 21 birds contained serum antibody but three produced AFC. The four viraemic line 21 birds which lacked AFC occurred later in the experiment and had a higher level of virus than the three viraemic line 21 birds which possessed AFC. This suggests that most line 21 birds do not control HPRS-103 and eventually become anergic. PMID- 9368963 TI - Spontaneous mouse mammary tumours: incidence and cytokeratin expression. AB - The purpose of this study was to advance our knowledge of the histogenesis of spontaneous mammary tumours in laboratory mice. Normal mammary tissue and 19 spontaneous mammary tumours from adult female mice were examined using monoclonal and polyclonal antibodies differing in their recognition of various cytokeratin intermediate filament proteins (CKs). All neoplasms were intraductal and were invasive carcinomas with a tubular, papillary, cystic or solid growth pattern. CK8-positive reactions were detected in the normal alveolar and ductal epithelia and CK5- and CK14-positive reactions were seen in myoepithelial cells of nonlactating mammary glands. Positive staining for CK5 and CK8 was detected in all tumours and CK14 was expressed in those with a papillary pattern. Comparisons between non-lactating glands and tumours indicated that the neoplasms were well or moderately differentiated, there was no squamoid differentiation and that they arose from the alveoli and duct system, not the myoepithelial cells. PMID- 9368964 TI - Detection of Mycoplasma mycoides subspecies mycoides by growth-inhibition using monoclonal antibodies. AB - A pool of three monoclonal antibodies, 3H12, 6D11 and 2A3, inhibited the in vitro growth of 12 Mycoplasma mycoides subspecies mycoides small colony (MmmSC) strains and seven Mycoplasma mycoides subspecies mycoides large colony (MmmLC) strains. This test did not cross-react with other 16 Mycoplasma mycoides cluster and nine non-Mycoplasma mycoides cluster strains representing 13 different species. Although MmmSC was not differentiated from MmmLC, the monoclonal antibodies distinguished both M mycoides subspecies mycoides biotypes from the other Mycoplasma species tested in contrast to results with polyclonal antisera. PMID- 9368966 TI - The variation in excretory urinary glycyl-prolyl dipeptidyl aminopeptidase in dogs. AB - We studied the excretory variation of urinary glycyl-prolyl dipeptidyl aminopeptidase (GP-DAP, EC 3.4.14.5) in dogs. Adult domestic mongrel dogs (seven males and nine females, 7.5 to 13 kg bodyweight) which were considered to be healthy by laboratory tests were used. Urine and blood samples were obtained every four hours. Urine volume was measured for each sample and urine GP-DAP activity, and creatinine levels were determined. Creatinine clearance, creatinine excretion, GP-DAP activity and GP-DAP index (GP-DAP/Cr ratio) did not show any significant variation between the time periods. However, urine volume and urinary GP-DAP excretion significantly increased from 8:00 am to 12:00 pm. The GP-DAP index in spot urine samples showed low correlation with 24 hour GP-DAP excretion. In addition, a sex difference was observed in GP-DAP excretion. In conclusion, urinary GP-DAP excretion showed a circadian variation and sex difference. Therefore, GP-DAP in spot urine is not of use for the detection of renal disorders, and the 24-hour excretion value of GP-DAP should be determined. PMID- 9368965 TI - Infrared and atomic spectrometry analysis of the mineral composition of a series of equine sabulous material samples and urinary calculi. AB - Atomic spectrometry has been used in 20 samples of equine urinary sabulous deposits in order to detect minor elements accompanying the predominant element, calcium, which is present in the form of calcium carbonate (calcite and/or vaterite). The elements measured have been (besides calcium) magnesium, sodium, potassium, iron, copper and manganese. Phosphates, sulphates and silica are frequently present as minor constituents of equine urinary sabulous deposits and uroliths, but their detection can be difficult by infrared (IR) spectroscopy in the original samples due to overlapping with the bands of calcium carbonate. For that reason, the calcination residues of six urinary calculi and 33 samples of sabulous material have been studied by IR spectroscopy and energy dispersive X ray (EDX) analysis. The results confirm the presence of the above mentioned minor constituents in most samples studied. PMID- 9368967 TI - Detection of Clostridium perfringens alpha toxin by enzyme-linked immunosorbent assay. AB - An enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of Clostridium perfringens alpha toxin in intestinal contents of animals which have died of suspected C perfringens type A enterotoxaemia. The test can also be used for testing culture supernatants of C perfringens isolates for the presence of alpha toxin. The test was sensitive and quantitative detecting toxin down to the 25ng level. The use of the ELISA for the detection of alpha toxin in conjunction with those for epsilon toxin and beta toxin, allows the differential diagnosis of C perfringens types A, B, C and D enterotoxaemias from samples of intestinal contents and the typing of cultures of C perfringens. PMID- 9368968 TI - [Job stressors in software developers--a comparison with other occupations]. AB - The aim of this study is to investigate the difference in job stressors among software developers, the sales staff and the clerical staff (n = 2,079) in two companies (A Co. and B Co.) using a self-administered questionnaire that included a job stressor scale and the 30-item General Health Questionnaire (GHQ). We developed the job stressor scale based on the interviews with out-patients who engaged in software development and previous studies about job stressors. Factor analysis with a seven-factor solution showed that seven subscales were abstracted from the job stressor scale, namely, quantitative load of work, dissatisfaction with work, demanding work, uneasiness about work, human relations, ambiguity of work and shortage of private time. Each subscale was significantly (r = .313 .442, p < 0.0001) correlated with the GHQ score and proved to be a reliable instrument, as indicated by a Cronbach's alpha of greater than 0.73. Stepwise multiple regression analysis revealed that quantitative load of work and shortage of private time subscale scores were significantly high in software developers in A Co. Software developers in A Co. tended to score higher (P < .10) than the others in demanding work and ambiguity of work subscale. All subscale scores were significantly low in the clerical staff in B Co. There was no significant difference between the sales staff and software developers in B Co. Results of the interviews with out-patients showed that demanding work, hard deadline, ambiguity of work and precarious work would cause trouble in software developers. The implications of these findings with respect to occupational issues related to software developers are discussed. PMID- 9368969 TI - [Blood biochemical properties in male workers analysed according to body type]. AB - The characteristics of body type, serum lipids and blood pressure in male blue workers were evaluated. The subjects were 1,705 healthy men aged 40.3 +/- 4.33 years, and were classified into 4 groups according to body mass index: BMI; lean (group L: BMI < 20), normal (group N: 20 < or = BMI < 24), mildly obese (group MO: BMI 24 to 26.5) and obese group (group O: BMI > 26.5). The physical characteristics, blood pressure and 14 blood constituent items were measured. Groups L, N, MO and O accounted for 8.5, 53.4, 28.6, and 9.4% of all subjects, that is the obese body type (MO and O groups) occupied 38%. Rest systolic and diastolic blood pressure were positively related to BMI. Most blood constituent items biochemically analyzed increased in proportion to BMI values. The Trigriceride level was 88.5, 112.2, 152.8 and 171.9 mg/dl in groups L, N, MO and O, respectively. The Trigriceride level in groups MO and O were about the upper limit of the normal range. The total cholesterol level was in the normal range in 4 groups, but was higher in the MO and O groups than in groups L and N. The HDL cholesterol level was low in inverse proportion to BMI, that is 58.2, 51.3, 47.6, and 42.6 mg/dl in groups L, N, MO, and O, respectively. Especially the values in group O were similar to the values in the aged and adult disease patients. A greater percentage of Japanese male workers were obese men and they risked developing atherosclerosis and adult diseases. the present study suggests that health education regarding exercise prescription and nutrition intake in daily life should be provided. PMID- 9368970 TI - [A dose-response study on inorganic mercury-induced DNA fragmentation in rat kidney]. PMID- 9368971 TI - [Usefulness of exercise electro-cardiography in a THP (Total Health Promotion Plan)]. AB - We conducted ergometer exercise electrocardiography (ergometry) on 3,477 subjects in a THP (Total Health Promotion Plan). One hundred cases in which abnormal findings were detected by ergometry were analyzed. In the hundred cases there were 3 patterns: abnormal ST change, 50 cases; abnormal reaction, 22 cases; and extreme increase in blood pressure, 28 cases. Electrocardiograms (ECG) in 78 of these 100 cases indicated no abnormalities. Of the 31 subjects who underwent further examinations, in 18 cases abnormal findings were detected, and further observation or treatment was necessary. They were over two thirds of the 26 cases requiring observation or treatment on further examination. In other words, exercise electrocardiography revealed more than 3 times as many problem cases as electrocardiography only. One hundred and four cases were analyzed, and among them abnormal findings on ECG made further examination or treatment necessary. Of 68 subjects with an abnormal ECG and who needed to undergo exercise electrocardiography, 51 (75%) had no need to undergo further examinations, because there were no abnormal findings on ergometry in the THP. Of the 104 subjects who underwent ECG examination at rest, 51 no longer needed to waste time, effort and expense on further medical evaluation. Ergometry in a THP serves as a medical check and as a means to decide the strength of exercise before the initiation of exercise training, which is very important in preventing coronary artery disease, rather than in detecting the disease. Ergometry is expensive and it takes a lot of time and labor, but it is necessary in ensuring the safety of exercise training and in prescribing proper exercise. This analysis has shown that ergometry in THP is very useful and cost effective in improving the accuracy of health examinations. PMID- 9368972 TI - Evaluation of the equine respiratory system using physical examination and endoscopy. AB - Defining respiratory disease is not always easy in the horse because auscultation with accurate interpretation of lung sounds can be difficult. However, performing a thorough physical examination, including rebreathing auscultation and percussion of the thorax and sinuses, is very useful in elucidating the problem. Endoscopic examination of the upper respiratory system is also critical for definitively diagnosing certain conditions. PMID- 9368973 TI - Techniques for sampling the respiratory tract of horses. AB - Field diagnostic tests for respiratory diseases are constantly evolving. With each new application, equine patients with sinusitis, acute and chronic bacterial and fungal pneumonia SAID, chronic obstructive pulmonary disease, pleuropneumonia or poor performance are managed with greater proficiency. All of these problems can be investigated adequately in the field. This article is a guide to sampling techniques relevant to the ambulatory clinician. PMID- 9368974 TI - Cytology of the respiratory tract. AB - Cytology can be a rewarding diagnostic technique in equine practice. The respiratory tract readily lends itself to sampling for cytologic evaluation from the upper to lower regions of the system. This article discusses preservation and staining techniques that will allow the practitioner to present satisfactory samples to the laboratory. General considerations for cytologic analysis are discussed as well as the specific findings for individual disorders of the respiratory tract. The proper use of cytologic findings in conjunction with other diagnostic techniques for the respiratory tract are also discussed. PMID- 9368975 TI - Field imaging of the respiratory tract. Radiology and ultrasonography. AB - This article addresses the current status and clinical opportunities for portable radiography and ultrasonography. Radiology is indicated for imaging the nasal cavity, larynx, pharynx and thin portions of the neck. In young foals, adequate radiographs of the entire respiratory tract may be possible. Ultrasonography is indicated in superficial parts of the head and neck, the pleural space and diseased parts of the lungfields. PMID- 9368977 TI - Inhaled medications and bronchodilator usage in the horse. AB - The advantages of aerosol medications include the direct, topical application to the target organ (airways); rapid effect; and low systemic availability. There are now more efficient methods for aerosol delivery that facilitate the use of increasingly sophisticated aerosol drugs. This article reviews the principles of aerosol deposition and the pharmacology of current medications. PMID- 9368976 TI - Antimicrobial therapy for respiratory disease. AB - Antimicrobial treatment is an important component of infectious respiratory disease management. However, across all systems in horses there is substantial deficit in definitive information concerning the efficacy of antimicrobials. This disassociation between laboratory data and antimicrobial efficacy and the obstacles to effective antimicrobial treatment should be understood. PMID- 9368978 TI - Immune therapy in respiratory disease. AB - Pharmacologic manipulation of pulmonary immunity plays an important role in primary and adjunct therapy for equine respiratory disease. Frequent exposure to respiratory viral pathogens, strenuous exercise, long distance transport, and inhalation of harmful substances destroy various aspects of the pulmonary defense system and predispose performance horses to development of infectious and noninfectious respiratory disease. Pulmonary immunity may be bolstered by nonspecific immunostimulants to combat primary or secondary immunodeficiency. State of the art technology improves active and passive-specific immunity for prevention of common infectious respiratory diseases in horses. Immuno suppressive therapy can attenuate hyperreactive pulmonary immune responses in horses with allergic airway disease. PMID- 9368979 TI - Small airway disease as a vanguard for chronic obstructive pulmonary disease. AB - Equine allergic small airway disease is a highly prevalent respiratory condition among the stabled horse population. With the assistance of new diagnostic tools such as bronchoalveolar lavage, the condition can be recognized in young performing horses. The pathophysiological and clinical features resemble an earlier stage of chronic obstructive pulmonary disease as determined by the appearance of specific inflammatory cells. Although environmental management is paramount in controlling the disease, proper selective therapeutic regimens are as important to reduce the concurrent inflammation and to reduce exacerbations of the disease. PMID- 9368980 TI - Field examination of the equine patient with nasal discharge. AB - This article describes the field investigation of horses with nasal discharge (serous, purulent, blood and feed). Flow charts on how to evaluate affected horses, and photographs of the examination procedures and of horses affected with nasal discharge are included. PMID- 9368981 TI - Poor performance and field evaluation of the respiratory system. AB - A thorough examination of the respiratory system is an important part of the work up for poor performance in horses. This article provides a systematic approach to field evaluation of horses with poor performance due to respiratory system dysfunction. The information is organized to help the reader evaluate pertinent historical and physical examination findings so that a list of differential diagnoses can be generated. Also, pertinent ancillary diagnostic modalities that can help further characterize and localize causes for respiratory dysfunction in horses presented for poor performance are discussed. PMID- 9368982 TI - Advanced diagnostic imaging modalities available at the referral center. AB - While many equine diagnostic imaging procedures can be done in field, some procedures require specialized facilities, equipment or expertise which are generally only available in referral or specialty practices. As client awareness of the availability and advantages of these diagnostic procedures increases, veterinarians are faced with the increasing opportunity to utilize these services to provide optimal patient care. A working knowledge of the value and limitations of these methods is required to help guide veterinarians and clients in the selection of additional, and sometimes costly, diagnostic tests. PMID- 9368983 TI - Economic impact associated with respiratory disease in beef cattle. AB - The data presented consistently demonstrated the cost of BRD from weaning to the packers to be approximately 7% of the total production cost when compared to animals with health respiratory tracts. As a clinician it is distressing to feel that we cannot accurately identify all the animals that require treatment. Greater emphasis must be placed on prevention of BRD. PMID- 9368984 TI - Dairy calf pneumonia. The disease and its impact. AB - The author discusses the syndrome of respiratory, disease in dairy calves, reviewing the disease and the causative agents. Attention is given to the epidemiology of the disease with discussion of morbidity, mortality, proportionate mortality and risk factors associated with dairy calf pneumonia. The economic impact of dairy calf pneumonia is discussed in detail and management options for calf rearing are suggested. PMID- 9368985 TI - Advances in pulmonary immunology. AB - Advances in pulmonary immunology often begin with better understanding of the mechanisms of pulmonary defenses. This leads to new technologies or better use of existing technologies to prevent pneumonia. These can be validated in challenge models, but ultimately, advances in pulmonary immunology come from demonstration that a management strategy reduces the burden of disease in a production setting. This can be difficult, and may require team efforts from producers, allied industry, and academia. Each team member brings a unique perspective and set of resources to the endeavor. The alternative is to use immunoenhancing management strategies based on extrapolation and faith. PMID- 9368986 TI - A molecular genetic approach to improved animal health. The effect of interferon genotype on the severity of experimental bovine herpesvirus-1 infection. AB - In the past decade, biotechnology has brought veterinary medicine an increased understanding of the effects of genetic background on disease resistance and production traits. Specific point mutations have been identified for a number of genetic diseases and genetic testing; selective breeding programs can eliminate these diseases from the population. Complex traits such as disease resistance and production traits are thought to be under the control of multiple genes, making their manipulation more difficult. Because of their antiviral and immune modulating properties, interferons may be a role in the host defense against viral infection. The Type I interferon gene family has been detailed in cattle and consists of approximately 32 genes clustered together on bovine chromosome 8. These genes are very polymorphic in the population, enabling studies on the association between alleles at specific interferon loci and the severity of clinical diseases following experimental Bovine Herpesvirus-1 infection. Associations were observed between specific IFN genotypes and increased severity of clinical disease in a population of unrelated cattle. With a better understanding of IFNs at the genetic level, it may eventually be possible to manipulate the IFN response for the therapeutic benefit of cattle, and lessen the economic impact of specific diseases on cattle producers. PMID- 9368987 TI - Respiratory problems of newborn calves. AB - Cardiopulmonary development of fetus is a timely event that proceeds to the point that birth can take place. Calves may be born premature, and because of surfactant deficiency, develop the respiratory distress syndrome. More research needs to be done on fetal lung development in calves to determine the age when maturity has been reached for compatibility with extrauterine life. Also, more specific therapy regimens need to be developed that will enhance lung development. The birthing process is a major event that must proceed in a timely fashion. Any delay in delivery will compromise further the already hypoxic fetus. Practitioners need to recognize the severely hypoxic/ asphyxiated calf and be prepared to therapeutically support the cardiopulmonary systems. PMID- 9368989 TI - Infectious bovine rhinotracheitis, parainfluenza-3, and respiratory coronavirus. AB - A number of viruses have been proven to be primary respiratory pathogens of cattle. Viruses may play an important role in making cattle susceptible to secondary respiratory bacterial pathogens. Epidemiology, pathogenesis, laboratory diagnosis, and important properties in infectious bovine rhinotracheitis (IBR), parainfluenza-3 (PI-3), and bovine respiratory coronavirus (BRCV) are described in this article. PMID- 9368988 TI - Bovine respiratory syncytial virus. AB - Since the first report of BRSV in the 1970s, the understanding of this agent and its respective disease has increased dramatically. Current evidence supports a major role for this virus in bovine respiratory disease. Advances in diagnostics have increased the ability to demonstrate this virus in field outbreaks of respiratory disease. The clinical signs and pathologic features have been well described, and vaccines are available to aid in prevention and control. Still, many questions remain to be answered with respect to BRSV. It appears there may be antigenic subgroups of BRSV, but the epidemiologic significance and relevance to immunization of this remains unknown. The question of differences in virulence among isolates of this virus has yet to be addressed. From an epidemiologic standpoint, the means by which BRSV perpetuates in the cattle population has yet to be elucidated. Although progress has been made in understanding the pathogenesis and immune response to BRSV, the mechanism of disease production and immune protection is incomplete. Lastly, efficacy testing of existing vaccines need to continue, as well as the development of new vaccines and new approaches to vaccination. PMID- 9368990 TI - Bovine respiratory tract disease caused by bovine viral diarrhea virus. AB - Although several viruses and bacteria are capable of inducing bovine respiratory tract disease, a pivotal organism in the cause of this complex disease may be bovine viral diarrhea virus (BVDV). Circumstantial evidence has long supported this hypothesis. It is frequently present in diseased respiratory tract tissues often together with other viruses or bacteria. Field observations suggest marked synergism occurs. Researchers have confirmed that, in most instances, the virus itself elicits only a mild respiratory tract disease in susceptible calves, but some strains may be much more pneumo-pathogenic than others. Experimental evidence now supports the hypothesis, that BVDV markedly enhances respiratory tract disease caused by IBRV, BRSV, or Pasteurella haemolytica; that it impairs pulmonary immunity; and that it, by itself, may produce mild respiratory tract disease. PMID- 9368992 TI - Allergic respiratory disease. AB - Allergic rhinitis and extrinsic allergic alveolitis are the most common allergic disorders of the bovine respiratory system. Environmental and management factors play significant roles in the pathogenesis of these disorders. When compared to infectious or toxic respiratory disease, allergic respiratory disease is relatively rare and of far less economic importance in North American cattle; however, the environmental and management conditions conducive to these diseases exist in many regions. Therefore, familiarity with the clinical and epidemiologic features of these unique diseases will aid the veterinarian in establishing an accurate diagnosis. Signs of respiratory dysfunction are common to anaphylactic and anaphylactoid reactions. Early recognition of these adverse reactions will provide the practitioner with the greatest chance of successful treatment. PMID- 9368991 TI - Bacterial pneumonia. AB - Bacteria play a critical role in the severe pneumonia and fatalities associated with the bovine respiratory disease complex. Although numerous bacteria have the potential to cause pneumonia, only a small number of these are responsible for the majority of cases of disease. Virulence and immunogenic characteristics of these organisms are important determinants of the host response to infection. These bacterial characteristics are reviewed and applied to a discussion of the epidemiology, pathogenesis, and prevention of bacterial pneumonia is also discussed. PMID- 9368993 TI - Respiratory diagnostic pathology. AB - Effective treatment and control of bovine respiratory disease is dependent upon an accurate diagnosis. This article discusses the approach to diagnosis of bovine respiratory disease from the perspective of respiratory pathology. Topics covered include necropsy examination of the respiratory system, sample collection and submission, and the gross, and histopathologic lesions of the upper and lower bovine respiratory system. PMID- 9368994 TI - Antimicrobial therapy of bovine respiratory disease. AB - Our challenge in therapy of BRD is the selection of the appropriate therapy from antimicrobials with long-standing histories and newer compounds. The proliferation of new antimicrobials for BRD makes it difficult to justify the extralabel use of nonlabeled compounds. Evaluation of the BRD case definition and treatment population should be the first steps in selecting therapy and evaluating incidences of poor response. PMID- 9368995 TI - Ancillary therapy of bovine respiratory disease. AB - Ancillary therapy for bovine respiratory disease is covered with an emphasis on anti-inflammatories. Theoretic rationale and any available clinical data are reviewed for glucocorticosteroids as well as nonsteroidal anti-inflammatory drugs such as phenylbutazone, flunixin meglumine, and aspirin. Antihistamines, immunomodulators, diuretics, and bronchodilators are also discussed. PMID- 9368996 TI - Surgery of the respiratory system. AB - Diseases affecting the respiratory tract are common in cattle; however, surgery required for treatment of these diseases is infrequent. Therefore, veterinarians may be reluctant to perform these surgical procedures. Familiarity with the variety and complexity involved in various surgical procedures should reduce this anxiety. When used, surgery of the respiratory tract can offer significant benefit to the patient and profitable returns to the owner. PMID- 9368997 TI - Preventative programs for respiratory disease in cow/calf operations. AB - Control of respiratory disease in cow/calf operations presents many challenges. The incidence of disease in the suckling calf is not well documented and the logistics of handling range animals make control programs difficult to implement. Health programs have to be built around normal working patterns, and these patterns may not provide the best "fit" for immune management of the calf. Weaned calves undergo significant disease challenge when they enter typical marketing channels. This provides the potential for high levels of calf morbidity, mortality, medicine costs, and losses from decreased performance as they arrive at a stocker operation or feedyard. If preweaning calf health and preconditioning programs are used, they must be planned so that the producer has an opportunity to obtain a return on their investment. Options for increasing calf weight marketed, certified calf health sales, or retained ownership through the next phase of production should be evaluated carefully. Any potential increase in calf value must be weighed against program costs. This affords the veterinarian an opportunity to build on traditional disease management and prevention skills and expand their influence in overall ranch management. PMID- 9368998 TI - Bears and beavers in Scotland? The call of the wild comes to congress. PMID- 9368999 TI - Organ transplants: developing an ethical framework. PMID- 9369000 TI - Variations in the force applied to flexion tests of the distal limb of horses. AB - A pressure-sensitive device was developed to measure the force applied to flexion tests of the distal limb of horses. The mean force applied by a group of experienced clinicians was 150 N which results in a moment on the flexed fetlock joint of about 28.5 Nm. The coefficient of variation of the force applied by one experienced clinician was only about 12 per cent, but the coefficient of variation between clinicians was considerably higher (20 per cent), irrespective of whether the clinicians were considered to be experienced or not. The mean force applied by a group of women examiners (114 N) was significantly lower than that applied by the group of male examiners. It is concluded that the flexion test used in the clinical examination of the locomotor system of the horse should be better standardised. PMID- 9369001 TI - Treatment of canine pyoderma with co-amoxyclav: a comparison of two dose rates. AB - The efficacy of oral co-amoxyclav, administered twice daily for up to 12 weeks either at the manufacturer's dose rate of 12.5 mg/kg or at 25.0 mg/kg, in curing the lesions of canine folliculitis, furunculosis and cellulitis was compared in a blind study. A total of 97 dogs entered the trial and 67 completed it. There was no significant difference in the rate of cure or the duration of therapy. The lesions of folliculitis were cured in 91.5 per cent of cases, in a mean period of 25.3 days. Furunculosis and cellulitis were cured respectively in 87.5 per cent and 60.0 per cent of the dogs, in mean periods of 37.6 and 44.7 days. The standard dose rate was very effective in folliculitis and furunculosis and there was no benefit in doubling the dose. Too few cases of cellulitis were treated to provide a reliable dose comparison. PMID- 9369002 TI - Effect of chemoprophylaxis with an ivermectin sustained-release bolus on acquired resistance to gastrointestinal parasites in cattle. AB - The influence of chemoprophylaxis with an ivermectin sustained-release bolus in the first grazing season on the resistance of cattle to gastrointestinal nematodes during the following grazing season was investigated. In 1993 and 1994 dairy replacement calves were either given one bolus at the start of their first grazing season or left untreated. The two groups were grazed separately on a pasture that was divided into two similar sized paddocks. Faecal egg counts, serum pepsinogen and antibody levels were measured to evaluate host-parasite contact. Pasture infection levels were estimated by pasture larval counts and worm counts in tracer calves. After winter housing the animals were monitored during their second grazing season on a pasture that was also divided into two similar sized paddocks. Acquired resistance to gastrointestinal nematodes was evaluated by faecal egg counts and weight gains. Again, pasture infection levels were determined and pepsinogen and antibody levels were measured. During the first grazing seasons gastrointestinal nematode infections were controlled very effectively by the bolus, as shown by the greater weight gains, the negligible faecal egg counts and the low serum pepsinogen and antibody levels in the treated calves. In contrast, all parameters showed extensive parasite-host contact in the untreated animals. The efficient prophylaxis in the treated groups resulted in low levels of larval contamination on the paddocks grazed by the treated animals, compared to moderate infection levels at the end of both first grazing seasons on the paddocks grazed by the untreated animals. During the second grazing seasons (1994 and 1995) the faecal egg output was low in all groups. Although in the previously treated animals faecal egg counts were consistently higher, the differences were minimal, resulting in comparable levels of larval contamination on both paddocks. Serum pepsinogen and antibody levels were not significantly different between the groups and indicated a similar level of larval uptake on both paddocks. No negative effect of the previous chemoprophylaxis on the clinical condition and the weight gain of the second season grazing animals was observed. PMID- 9369003 TI - Detection of Streptococcus equi in equine nasal swabs and washes by DNA amplification. PMID- 9369004 TI - Laboratory tests of phenolic disinfectants as oocysticides against the chicken coccidium Eimeria tenella. PMID- 9369005 TI - Syndrome in sheep resembling mucosal disease in cattle. PMID- 9369006 TI - Veterinary public health. PMID- 9369007 TI - Dissemination of rabies. PMID- 9369008 TI - Neighboring methoxyl participation in the acid catalyzed methoxylation of methylene-interrupted fatty acids. AB - The boron trifluoride-methanol derivatization of methyl 9,12-octadecadienoate was studied. This methylene-interrupted diene was reacted with 50% BF3-MeOH for 15 h at 0-5 degrees C and the four monomethoxy and two dimethoxy derivatives thus obtained were analyzed by gas chromatography-mass spectrometry. The only dimethoxy adducts observed were characterized as methyl 9,12 dimethoxyoctadecanoate and methyl 10,13-dimethoxyoctadecanoate. The complete regiospecificity observed in the formation of the dimethoxy adducts is best explained by a common O-methyltetrahydrofuranium ion as the only intermediate under these reaction conditions. PMID- 9369009 TI - Methylmercury-induced alterations in lung and pulmonary surfactant properties of adult mice. AB - Exposure to methylmercuric chloride (MMC) has been shown to significantly affect development of the lung and pulmonary surfactant system of the fetus. Preliminary results suggest it may also affect adult lung and associated bronchoalveolar lavage (BAL), which represents the extracellular surfactant pool. To determine if mercury exposure has the potential to alter surfactant function, adult mice were treated with MMC, 15 mg/kg by intragastric intubation on 4 successive days. BAL was collected by repeated intratracheal lavage 24 h after the last treatment. Nucleated cell numbers in lavage were determined. Tissue was prepared for scanning electron microscopy (SEM). Lavage fluid was extracted into chloroform:methanol and phospholipid concentration determined. A sample of the extract was used at a constant phospholipid concentration to measure surface activity on a bubble surfactometer. Lung weight to body weight ratio increased whereas total numbers of nucleated cells in BAL were not altered by MMC. SEM of samples from lungs of animals exposed to MMC showed normal architecture. Surface tension measurements suggest that the mean time to minimum surface tension and the minimum surface tension were greater in BAL from mice exposed to MMC for 4 days. In addition samples of BAL were prepared for Fourier-transform infrared spectrophotometry (FT-IR). Spectra showed changes in both lipid and protein components of BAL. Morphometric analyses of micrographs showed that mean alveolar diameter was reduced and wall thickness increased after mercury exposure. These results suggest that methylmercury exposure may significantly affect surface tension characteristics and composition of BAL, possibly through leakage of edematous interstitial tissue. PMID- 9369010 TI - Improved synthesis of myo-inositol 1-(4-nitrophenyl hydrogen phosphate), a chromogenic substrate for phosphatidylinositol-specific phospholipase C. PMID- 9369011 TI - Inferences about the origin of a field cricket hybrid zone from a mitochondrial DNA phylogeny. AB - Two closely related eastern North American field crickets, Gryllus firmus and G. pennsylvanicus, hybridize along a zone that extends from Connecticut and the Hudson River Valley, south along the eastern front of the Appalachian Mountains to at least Virginia. Here we use mitochondrial DNA (mtDNA) sequences to construct a population phylogeny for this pair of hybridizing cricket species. Using a phylogenetic approach, we attempt to discriminate between alternative population histories (secondary contact vs. primary intergradation) leading to formation of the hybrid zone. A strict consensus tree, based on > 1600 bp of the COI-COII region of the mtDNA genome, reveals four exclusive groups, which correspond to regional grouping of conspecific crickets. Surprisingly, the mtDNA sequence data do not reveal any synapomorphies for either G. pennsylvanicus or G. firmus. However, the mtDNA data do reveal a clear north-south split within each of the cricket species, a pattern not seen for morphological or other molecular characters. The biogeographical history of the north-south divergence events remains a puzzle. Observed gene genealogies support a model of secondary contact for the southern part of the hybrid zone. Sequence divergence data argue that lineages currently found in New York and New England were already distinct when this region became habitable following the most recent glaciation. PMID- 9369012 TI - Isolation of microsatellite DNA markers from a passerine bird, Dendroica petechia (the yellow warbler), and their use in population studies. AB - We describe the isolation and genetic characterization of five microsatellite loci in a passerine bird, the yellow warbler Dendroica petechia, and assess their use for various types of population-level analysis using data from two breeding populations. All five loci show levels of variability comparable to those observed in other vertebrates (Hexp = 0.388-0.989). One locus, Dp mu 05, is highly variable with 46 alleles detected in 41 individuals. All loci appeared to segregate in a Mendelian fashion as judged by patterns of inheritance in known families. However, one locus showed a significant heterozygote deficiency in one population suggesting the possible presence of null alleles at this locus. These markers provide a highly accurate system for determination of parentage in this species: the probability of detecting extrapair fertilization by males given known maternity was 0.999 in each of two separate populations. Comparison of allele frequencies and genetic distances between the two populations showed no evidence for significant differences in allele frequencies at individual loci, whereas the overall genetic distance and FST-value are significantly different from zero suggesting weak differentiation. Finally, cross-species amplification experiments showed that at least one locus appears to amplify products in a wide range of birds including nonpasserine species. Thus, our results demonstrate that these loci will provide a useful set of genetic information for addressing a wide range of population-level analyses in this and other bird species. PMID- 9369013 TI - Molecular population studies of Simulium damnosum s.l. (Diptera: Simuliidae) using a novel interspersed repetitive DNA marker. AB - Simulium damnosum s.l., the vector of West African onchocerciasis, has been the target of a major insect control initiative for the past 20 years. However, attempts to study the migration patterns of reinvading infective flies into controlled areas have been restricted by the lack of suitable genetic markers. Here, the results of the first population-level study of S. damnosum s.l. using a repetitive DNA marker, pSO11, are presented. Sequence analysis of pSO11 revealed a complex internal pattern of repetition and an open reading frame with 56.8 per cent similarity to a mouse retrotransposon protein. Combined with an interspersed genomic distribution, the internal structure of pSO11 suggested that it represents the 5' half of a transposable element. The genomic diversity of the sequence was analysed using Southern blot analysis of genomic DNA. Data were collected from 475 individuals from the island of Bioko (in Equatorial Guinea), Cameroon, Cote d'Ivoire and Sierra Leone. The results indicate that pSO11 is useful as an indicator of genomic diversity and that the experimental design used here permits comparison of an approximately random sample of chromosomal loci. Making this assumption, estimates of homozygosity based on pSO11 diversity were used to study inter- and intraspecific variability. The results indicate that pSO11 is potentially useful for studying population-level processes in S. damnosum s.l. PMID- 9369015 TI - Solution structures of staphylococcal nuclease from multidimensional, multinuclear NMR: nuclease-H124L and its ternary complex with Ca2+ and thymidine 3',5'-bisphosphate. AB - The solution structures of staphylococcal nuclease (nuclease) H124L and its ternary complex, (nuclease-H124L).pdTp.Ca2+, were determined by ab initio dynamic simulated annealing using 1925 NOE, 119 phi, 20 chi 1 and 112 hydrogen bond constraints for the free protein, and 2003 NOE, 118 phi, 20 chi 1 and 114 hydrogen bond constraints for the ternary complex. In both cases, the final structures display only small deviations from idealized covalent geometry. In structured regions, the overall root-mean-square deviations from mean atomic coordinates are 0.46 (+/- 0.05) A and 0.41 (+/- 0.05) A for the backbone heavy atoms of nuclease and its ternary complex, respectively. The backbone conformations of residues in the loop formed by Arg81-Gly86, which is adjacent to the active site, are more precisely defined in the ternary complex than in unligated nuclease. Also, the protein side chains that show NOEs and evidence for hydrogen bonds to pdTp (Arg35, Lys84, Tyr85, Arg87, Tyr113, and Tyr115) are better defined in the ternary complex. As has been observed previously in the X ray structures of nuclease-WT, the binding of pdTp causes the backbone of Tyr113 to change from an extended to a left-handed alpha-helical conformation. The NMR structures reported here were compared with available X-ray structures: nuclease H124L [Truckses et al. (1996) Protein Sci., 5, 1907-1916] and the ternary complex of wild-type staphylococcal nuclease [Loll and Lattman (1989) Proteins Struct. Funct. Genet., 5, 183-201]. Overall, the solution structures of nuclease-H124L are consistent with these crystal structures, but small differences were observed between the structures in the solution and crystal environments. These included differences in the conformations of certain side chains, a reduction in the extent of helix 1 in solution, and many fewer hydrogen bonds involving side chains in solution. PMID- 9369018 TI - Specialized scanning ion-conductance microscope for imaging of living cells. AB - A specialized scanning ion conductance microscope (SICM) for imaging living cells has been developed from a conventional patch-clamp apparatus, which uses a glass micropipette as the sensitive probe. In contrast with other types of scanning probe microscope, the SICM probe has significant advantages for imaging living cells: it is most suitable for imaging samples immersed in water solutions; and since the probe senses ion current and does not need physical contact with the sample during the scan, any preliminary preparation of cells (fixation or adherence to a substrate) is unnecessary. We have successfully imaged murine melanocytes in growth medium. The microscope images the highly convoluted surface structures without damaging or deforming them, and reveals the true, three dimensional relief of the cells. This instrument has considerable ability to operate, potentially simultaneously, in applications as diverse as real-time microscopy, electrophysiology, micromanipulation and drug delivery. PMID- 9369017 TI - Main-chain NMR assignments for AsiA. PMID- 9369014 TI - Protein phi and psi dihedral restraints determined from multidimensional hypersurface correlations of backbone chemical shifts and their use in the determination of protein tertiary structures. AB - The chemical shifts of the backbone atoms of proteins can be used to obtain restraints that can be incorporated into structure determination methods. Each chemical shift can be used to define a restraint and these restraints can be simultaneously used to define the local, secondary structure features. The global fold can be determined by a combined use of the chemical shift based restraints along with the long-range information present in the NOEs of partially deuterated proteins or the amide-amide NOEs but not from such limited NOE data sets alone. This approach has been demonstrated to be capable of determining the overall folding pattern of four proteins. This suggests that solution-state NMR methods can be extended to the structure determination of larger proteins by using the information present in the chemical shifts of the backbone atoms along with the data that can be obtained on a small number of labeled forms. PMID- 9369019 TI - The in situ architecture of Escherichia coli ribosomal RNA derived by electron spectroscopic imaging and three-dimensional reconstruction. AB - The structures of the large and small ribosomal subunits of Escherichia coli were reconstructed using spectroscopic electron microscopy and quaternion-assisted angular reconstitution to resolutions of better than 4 nm. In addition, the distributions of phosphorus within these complexes were reconstructed. The three dimensional reconstruction of the distribution of this atomic element is an extension of microanalysis (in two dimensions) for phosphorus identification and mapping, as a signature of the arrangement of the phosphate backbones of the constituent ribosomal RNAs. The results on both the phosphorus reconstructions and the total reconstructions (protein and ribosomal RNA) reveal several passageways through both subunits. The structures correspond favourably with other independent reconstructions of the whole E. coli ribosome from cryoelectron micrographs and their accompanying models of translation (Frank et al., Nature, 376, 441-444, 1995; Stark et al., Structure, 3, 815-821, 1995). The overall reconstructions in conjunction with the phosphorus (rRNA) distributions are the first to be achieved synchronously for this nucleoprotein complex. PMID- 9369020 TI - Freeze shattering: a simple and effective method for permeabilizing higher plant cell walls. AB - This article describes a practical technique for permeabilization of higher plant cell walls, which is usually one of the first steps required for immunolocalization of cellular components (and other cytological methods) in plant cell studies. Our strategy involves shattering the walls of cells while the tissues are frozen in liquid nitrogen. It replaces the use of wall degrading enzymes or the need to employ laborious sectioning or other mechanical means for providing access of probes to cells. Freeze-shattering retains the integrity of whole tissues and cells surprisingly well and thus is especially useful when used in conjunction with confocal laser scanning microscopy for recording the three dimensional arrangement of cytoskeletal elements in relation to cell shape. In this article, we demonstrate the effectiveness of this technique for anti-tubulin and anti-actin immunofluorescence and for rhodamine phalloidin labelling of the cytoskeleton in various higher plant tissues including onion root tip and bulb scale epidermis, Tradescantia stamen hairs and Arabidopsis leaf epidermis and mesophyll cells. PMID- 9369021 TI - Backscattered electron imaging of cultured cells: application to electron probe X ray microanalysis using a scanning electron microscope. AB - We report a simple method to study the elemental content in cultured human adherent cells by electron probe X-ray microanalysis with scanning electron microscopy. Cells were adapted to grow on polycarbonate tissue culture cell inserts, washed with distilled water, plunge-frozen with liquid nitrogen and freeze-dried. Unstained, freeze-dried cultured cells were visualized in the secondary and backscattered electron imaging modes of scanning electron microscopy. With backscattered electron imaging it was possible to identify unequivocally major subcellular compartments, i.e. the nucleus, nucleoli and cytoplasm. X-ray microanalysis was used simultaneously to determine the elemental content in cultured cells at the cellular level. In addition, we propose some improvements to optimize backscattered electron and X-ray signal collection. Our findings demonstrate that backscattered electron imaging offers a powerful method to examine whole, freeze-dried cultured cells for scanning electron probe X-ray microanalysis. PMID- 9369023 TI - Endothelial alterations and senile calcific aortic stenosis: an electron microscopic observation. AB - Calcific degeneration of aortic valves were investigated in 10 patients with senile calcific aortic stenosis by means of high resolution scanning electron microscopy (HR-SEM) and transmission electron microscopy (TEM). All the specimens obtained during aortic valve surgery HR-SEM and TEM examinations consistently showed various degrees of pathological alterations and calcification involving surface endothelium, underlying basement membranes and deeper layers of interweaving networks of collagen fiber bundles in the pars fibrosa of the valve tissues. Calcific deposits in the valve tissues always occurred in the vicinity of the endothelial defects and in the subendothelial structures just beneath the defective endothelium. The amount of calcific deposits in the valve tissues increased in proportion to the severity of endothelial damage and gradually decreased from the defective endothelial surface to the deeper layer of collagen tissue. In addition, apoptotic cell death, particularly of the fibrocytes in the valve tissue, was closely related to the severity of endothelial injury. Cellular fragments derived from the apoptotic cells were always associated with calcium deposits. Based on the above findings, our results provide evidence that the alteration of endothelial integrity plays a contributory role in calcific degeneration in the aortic valve leading to the development of senile calcific aortic stenosis. PMID- 9369022 TI - Effect of betel quid on catecholamine secretion from adrenal chromaffin cells. AB - Health damage and environmental pollution are serious problems caused by betel quid chewing in Taiwan. Many people acquire the habit of chewing betel quid due to its physiological effects, including increased stamina and a general feeling of well-being. In this study, a sympathetic model system of adrenal chromaffin cells and sensory evaluation were used to examine the physiological effects of betel quid and the interaction of all the ingredients (areca fruit, Piper betle inflorescence and red time paste) in betel quid. Physiological effects of cardioacceleration, a slightly drunk feeling, sweating and salivation occurred during the chewing of betel quid (a mixture of areca fruit, Piper betle inflorescence and red lime paste) and a mixture of areca fruit and red lime paste. Both induced much more basal catecholamine secretion from adrenal chromaffin cells than did other ingredients and combinations of ingredients. It was evident that the responses in the sympathetic model system were closely correlated with the physiological feeling of well-being. The inhibitory effects of all the chewing juices on catecholamine secretion evoked by carbachol and a high concentration of potassium (high K+) showed that they perhaps affected the calcium influx through voltage-sensitive channels or the steps involved in secretion after calcium entry to stimulate basal catecholamine secretion from chromaffin cells. PMID- 9369024 TI - The genome of Moloney murine leukemia virus can be integrated by the integrase of human immunodeficiency virus type 1 expressed alone in vivo. AB - An in vivo integration assay using the expressed human immunodeficiency virus type 1 (HIV-1) integrase (IN) protein and plasmids carrying a copy of the infectious Moloney murine leukemia virus (MuLV) provirus genome as substrates is presented. The HIV-1 IN gene was taken from vector pINSD and cloned into vector pXT1 to give pXT1-IN. Two and three nucleotides from the circle junction on one pair of U3 and U5 attachment (att) sequences on an infectious MuLV provirus vector pMLV-K were changed by means of site-directed mutagenesis to that of the corresponding HIV-1 att sequences to generate vector pMLV*(U3U5). The MuLV IN sequence was partially deleted for vectors pMLV-K and pMLV*(U3U5) to generate vectors pMLV delta IN and pMLV*(U3U5) delta IN. Integration of these wild type and MuLV IN partially deleted or att mutated MuLV provirus vectors in the transfected cells by the expressed HIV-1 IN was monitored by means of a non radioactive reverse transcriptase (RT) assay for released and collected virions. No RT activity was detected for the NIH/3T3 cell singly transfected with vector pMLV delta IN. However some RT activities were observed for the HIV-1 IN expressing cell transfected either with vectors pMLV delta IN or pMLV*(U3U5) delta IN. This indicated that in the absence of other HIV-1 proteins expressed the MuLV provirus genome was integrated by the expressed HIV-1 IN protein. The integration of these MuLV provirus genomes was further confirmed by polymerase chain reaction analysis on the genomic DNA extracted from the transfected cells using the MuLV IN sequence remained from partial deletion as a target. PMID- 9369025 TI - Cytotoxic and cytostatic effects of arecoline on oral mucosal fibroblasts. AB - Betel quid (BQ) chewing shows strong correlation to the incidence of oral submucous fibrosis and oral cancer in Taiwan. Arecoline, the main areca alkaloid, is considered to be one of the etiologic factors in BQ. To elucidate the role(s) of arecoline in the pathogenesis of BQ chewing related oral mucosal lesions, we used oral mucosal fibroblasts to study the effects of serum concentration, cell density, and incubation time on the cytotoxic response to arecoline. At a concentration less than 0.2 mM, arecoline was not cytotoxic to oral mucosal cells after 1, 3, and 6 days of incubation. After 3 days of incubation, the cytotoxic and cytostatic effects of arecoline became evident when the cells were exposed to higher concentrations of arecoline (0.2 mM) and serum (10% FCS). Exposure of cells (1 x 10(4) cells/well) to 0.2 mM of arecoline in 0.5% FCS for 3 and 6 days led to a 20% and 23% decrease, respectively, in the cell number, whereas exposure of cells (1 x 10(4) cells/well) to 0.2 mM arecoline in 10% FCS led to a 38% and 53% decrease, respectively, in cell number. At a higher cell density (5 x 10(4) and 1 x 10(5) cells/well), 0.2 mM arecoline led to less cytotoxicity (38% and 21% of decreasing in cell number, respectively) after 6 days of incubation. Our results indicated that arecoline was not mitogenic to oral mucosal fibroblasts, and that the cytotoxic and cytostatic effects of arecoline on oral mucosal fibroblasts could be modulated by the changes in the cell density, serum concentrations, and incubation time. PMID- 9369026 TI - The nonlinear finite element analysis and plantar pressure measurement for various shoe soles in heel region. AB - The most influential factor contributing to foot and shoe comfort is underfoot cushioning. The shock absorbing ability of footwear in the heel area is of particular importance in reducing the impact load during athletic activities and in therapeutic footwear prescribed for heel pain. Furthermore, foot care for foot problem patients is an important part of treatment and educational programs. Therefore, a well-designed sport shoe which can provide comfort and protection is essential. In order to design a functional shoe, biomechanics and other new technologies should be considered, and the design process should be examined in the biomechanics laboratory over and over. The design process requires too much time and effort since the entire experimental and test work can only be done after the prototype is manufactured. Therefore, this study tried to introduce the Finite Element Method (FEM) into the shoe design process by building a three dimensional FE model with various shoe soles and loading conditions. The material properties of shoe materials were tested using an Instron Testing Machine. An in shoe pressure insole was used to measure the plantar pressure in different ambulation conditions with various shoe constructions. The subject for this study was a healthy young male without any foot problem. The average plantar pressures obtained from approximately 50 steps in the heel region for each of the various conditions were collected. The results showed that the mean peak plantar pressure of the running situation was significantly higher than that of the walking situation as predicted, and that the insole could provide better cushioning compared to the other shoe constructions. The stress strain relationship for shoe materials was approximated better by a second-order nonlinear curve according to the Instron test. The results of the finite element method suggested that only the second-order nonlinear stress strain curve could correctly describe the shoe material, which also confirmed a potential valuable role for FEM in designing functional shoes. PMID- 9369027 TI - Control of metabolic flux in yeasts and fungi. PMID- 9369028 TI - The use of capillary electrophoresis for point-mutation screening. AB - Advances in capillary electrophoresis technology over the past three years have been rapid. Capillary electrophoresis offers high-throughput, high-resolution, automatic operation and on-line detection with automatic data acquisition, and this has stimulated its application to the analysis of DNA mutations. Many different PCR-based DNA-mutation assays have been developed for unknown and known mutations. This article compares conventional PCR-based mutation-detection assays with the methods developed for use with capillary electrophoresis. Future trends for mutation detection using capillary electrophoresis are also assessed, with a special emphasis on totally integrated, microchip capillary-electrophoresis-based mutation-detection systems. PMID- 9369030 TI - Polyunsaturated fatty acids, Part 2: Biotransformations and biotechnological applications. AB - The realization of the important biomedical roles of polyunsaturated fatty acids has led to the development of methods for obtaining and manipulating polyunsaturated lipids. Enzyme-mediated reactions have demonstrated unique advantages over chemical approaches and commercial lipase- and phospholipase catalysed processes have been developed to address the mid- to high-value polyunsaturated-lipid market. Research over the past two decades has also highlighted the broad spectrum of bioactive products derived from the oxidation of polyunsaturated fatty acids. The potential of these compounds in the flavour, fragrance, pharmaceutical and fine-chemical arenas has encouraged the elaboration of biotransformation strategies based on isolated enzymes and whole cells. PMID- 9369029 TI - Bacterial N-acyl-homoserine-lactone-dependent signalling and its potential biotechnological applications. AB - N-acyl homoserine lactones are bacterial signalling molecules involved in regulating diverse metabolic functions, particularly those relating to virulence, in concert with cell density. Each aspect of the signalling pathway, from production and recognition of the signal to expression of the target genes, offers a potential opportunity for exploitation. Attention is now focusing on the development of novel methods for bacterial enumeration, modulation of bacterial virulence and flexible, coordinated expression of heterologous genes through the use of N-acyl-homoserine-lactone-based systems. PMID- 9369031 TI - Alzheimer disease: protein-protein interaction and oxidative stress. AB - Alzheimer disease, the most prevalent dementia of the aged, is defined by the concurrence of two filamentous brain lesions: neurofibrillary tangles and senile plaques. The lesions are temporally and spatially correlated to each other and to cognitive impairment suggesting that is a interaction between neurofibrillary tangles and senile plaques that might play a role in disease pathogenesis. Here we present findings demonstrating specific interactions between the major protein components of the lesions. Such an interaction is likely important to lesion genesis and to the overall cognitive deficits seen clinically. Also important are forces that stabilize and cement abnormal interactions and protect them form removal. Oxidative post-translational modifications is probably one of the major mediators that by disrupting cellular homeostatic balance both promotes abnormal interactions and makes them resistant to proteolytic removal. Overall, these findings support the view that the lesions of Alzheimer disease are intimately involved in neuronal destructions. PMID- 9369032 TI - Effect of the temperature upon ultradian and circadian ERG amplitude rhythms during ontogeny of crayfish Procambarus clarkii. AB - The purpose of this work was to investigate whether the ultradian rhythms that are present prior the electroretinogram (ERG) amplitude circadian rhythm, and are superimposed upon it, during the different stages of development of the crayfish Procambarus clarkii are temperature sensitive, as well as the circadian rhythm. Temperature sensitivity was investigated using ERG amplitude recordings in free running conditions at high and low temperature from juvenile instars of different ages. All recordings were submitted to two types of statistical tests: X2 periodogram and power spectrum analysis. Cycles detected by both methods were selected from periodogram and Q10 was computed. Selected ultradian periods (ranging between 1.7 to 17.5 hrs.) seem to show temperature insensitivity that could imply temperature compensation, a property apparently shared with the emerging circadian period. These results support the endogenous nature of the ultradian ERG rhythms as well as their probably functional interaction with the circadian rhythm. PMID- 9369033 TI - Genetic salivary protein polymorphism in Mexican population. AB - Genetic polymorphism is the major contributor that affects human salivary composition. In order to determine the molecular phenotypes in saliva, it is important to know the distribution of proteins with specific functions which allows the clinical diagnosis of specific diseases. Unstimulated human whole saliva samples from 120 subjects were subjected to sodium dodecyl sulfate polyacrylamide slab gel electrophoresis (SDS-PAGE). The phenotype distribution of several molecules including MG1, MG2, alpha-Amylase, PRP-I and cystatins were similar. Qualitative and quantitative characteristics were specific in each subject. PMID- 9369034 TI - Immunoexpression of epidermal growth factor in odontogenesis of the offspring of alcoholic mice. AB - Several forms of cell perturbation have been associated with ethanol ingestion. Fetal alcohol syndrome (FAS) as well as diminished maxillofacial development and inhibition of cell regeneration in vitro and in vivo have been described. Epidermal growth factor (EGF) stimulates maxillofacial growth, DNA synthesis, and it is a potent mitogen for a number of various cell types. EGF exerts its effects on cells through binding to a specific cell surface receptor which leads to activation of a thyrosine kinase in the intracellular part of the receptor. The inhibitory effect of alcohol on EGF in the mouse dental follicle was studied in the offspring of alcoholic mothers using immunocytochemistry. Adult female mice were given 22% alcohol in their drinking water and fed a pelleted diet before and during pregnancy. Maternal blood alcohol levels were 262 +/- 1.3 mg/100 ml on gestation day 12.5. The offspring of the alcoholic and control mice were sacrificed on postnatal day 1.5, their mandibles were dissected, weighed and processed by routine immunocytochemistry with the following results. 1) Significant differences were found in mandible weight p < 0.01 after parturition. 2) The tooth germs in the offspring of ethanol treated mice were morphometrically smaller than those of control littermates. 3) Immunoexpression of EGF in the mandibular first molar of the control group was strong and homogeneous while in the experimental group the expression was light and heterogeneous. It is concluded that maternal alcoholism reduces EGF in the offspring. PMID- 9369036 TI - Six-minute walk test in patients with cardiac dysfunction. PMID- 9369035 TI - Structures in material transference and vitelline envelope formation in Betta splendens follicles. AB - Structures were found by transmission electron microscopy, they were located within follicular cells and the oocyte, and in the interspace between them in follicles of the teleost fish Betta splendens. Some structures with features characteristic or lamellar bodies were found in small follicles. The possible role of these structures in the formation of the vitelline envelope as well as in the material transference is discussed. Vacuoles, vesticles and particles intensely stained were found in the microvilli and the cortical cytoplasm of the oocyte at the onset of vitellogenesis. These results suggest that different substances present in the cellular components of the follicle might be transferred from cell to cell through the extracellular space and through the prolongations that cross the extracellular space. PMID- 9369037 TI - Non-surgical treatment of abdominal aortic aneurysms. AB - Percutaneous placement of an endovascular stent, with and without coils, in the treatment of large AAA in animal models is feasible, safe and effective. The covered stent sealed off AAA immediately after stent placement, however, it interrupted blood flow into arteries in the area covered by the stent. The uncovered stent prevented further expansion of the aneurysm and also significantly decreased the incidence of rupture. The long-term patency of branch arteries by the uncovered stent supported the possibility of safely using this approach in humans. Furthermore, either covered stent or uncovered stent with additional coils have the potential for treatment of acute aneurysm rupture or leaking. Most importantly, the aneurysm lumen in our model was gradually replaced by collagen after stent placement which further reduces the risk of aneurysm rupture: and this healing process was enhanced by the addition of coils. If proven safe and effective for humans as well, this technique has the potential for substantially reducing the morbidity and mortality associated with AAA. PMID- 9369038 TI - Aggressive lipid lowering treatment in coronary atherosclerosis. AB - Reduction of cholesterol by potent drugs in clinically symptomatic or asymptomatic patients with elevated cholesterol levels will substantially decrease the risk of coronary events. In selected cases more aggressive treatment of hyperlipidemia is necessary, such as in patients, homozygous for familial hypercholesterolemia, or subjects with severe coronary artery disease who are refractory to diet and drugs. LDL-apheresis, by which atherogenic lipoprotein particles are removed from the blood extracorporeally, is a therapeutic option in these cases. In this report a study is summarized, in which the effect of intervention with LDL-apheresis plus simvastatin was compared with conventional drug treatment alone in a group of patients with severe coronary artery disease with respect to changes in coronary atherosclerotic lesions and their functional impact. PMID- 9369039 TI - Stent implantation for spontaneous coronary dissection. AB - Spontaneous coronary artery dissection is a rare cause of acute myocardial infarction and sudden death. We report a case of diffuse spontaneous left coronary artery dissection occurring in the postpartum period, successfully treated by multiple stent implantation. Coronary angiography performed 3 months later showed no evidence of dissection and TIMI flow grade 3 in the treated coronary arteries. At 12-month follow-up the patient was asymptomatic. PMID- 9369040 TI - 1st Croatian Diabetology Congress. Abstracts. PMID- 9369041 TI - [Effects of cardiac output on PETCO2 and PaCO2 during combined inhalational epidural anesthesia]. AB - We investigated the effects of cardiac output on PETCO2 in anesthetized patients. We studied 8 adult patients undergoing long-lasting lower abdominal surgery. Anesthesia was maintained with epidural combined with inhalational anesthesia. The minute ventilation volume was kept constant at 10 ml.kg-1 x 10 cycles.min-1. PETCO2, PaCO2, and cardiac index, (CI) by thermodilution method were measured simultaneously. PaCO2 was corrected for body temperature for comparison with PETCO2. Approximate value of alveolar dead space to tidal volume ratio was calculated as VD/ VTalv = (PaCO2-PETCO2)/PaCO2. The measurements were repeated every 10 to 20 minutes under the steady body temperature. One hundred and six sets of data were obtained from these patients. PETCO2 as well as PaCO2 correlated positively with CI, while VD/VTalv did not correlate with CI. PETCO2 correlated positively with PaCO2, while it did not correlate with VD/VTa1v. When examined in individual patients, PETCO2 correlated positively with CI in 7 patients. PaCO2 correlated positively with CI in 6 patients, while VD/VTa1v correlated negatively with CI only in 2 patients, in whom CI showed a large fluctuation. PaCO2 correlated positively with PETCO2 in 8 patient, while VD/VTa1v correlated negatively with PETCO2 only in 1 patient. By multiple regression analysis, VD/VTa1v change accounted for only 20.0 +/- 15.3% of PETCO2 change, while PACO2 or PaCO2 change accounted for 79.3 +/- 16.7%. Decreased CI was associated with a decrease in oxygen uptake (VO2), and PaCO2 correlated positively with VO2. Decreased CI was also associated with an increase in VA/Q, and PaCO2 correlated negatively with VA/Q. Thus, PETCO2 decreased with decreasing cardiac output. A decrease in PACO2 explained the decrease in PETCO2 better than an increase in VD/VT did. Decreased cardiac output caused hypocapnia through decreased CO2 production and/or increased ventilation to perfusion ratio i.e. relative hyperventilation. PMID- 9369042 TI - [Diffusion of bupivacaine into the intercostal muscle following interpleural analgesia]. AB - To test the hypothesis that local anesthetic solution diffuses across the parietal pleura into the intercostal nerves in interpleural analgesia, tissue bupivacaine concentrations were assayed after interpleural injection of bupivacaine in rabbits. Thirty animals were killed at 10, 20, or 30 min after administration of 0.5% bupivacaine (1 ml.kg-1) into the left pleural cavity. The left intercostal muscle (lt-ICM), right intercostal muscle (rt-ICM) and femoral muscle (FM) were sampled immediately after killing the animals. Bupivacaine concentrations were analyzed by high-performance liquid chromatography. Mean bupivacaine concentrations in lt-ICM were 10.8 micrograms.g-1 at 10 min, 15.2 micrograms.g-1 at 20 min and 11.8 micrograms.g-1 at 30 min. On the other hand, the bupivacaine concentrations in rt-ICM and FM were less than 2.0 micrograms.g-1 at any sampling time. (P < 0.01 vs. lt-ICM). These results indicate that bupivacaine administered interpleurally diffuses from the pleural space into the ipsilateral intercostal muscle. Direct diffusion of bupivacaine could cause intercostal nerve block following interpleural analgesia. PMID- 9369043 TI - [Effects of nicorandil on regional cerebral oxygen saturation]. AB - Nicorandil is usually considered to be a potent antianginal agent characterized as a potassium channel opener. It has been suggested that it may exert similar action on cerebral vessels. We administered nicorandil to surgical patients under general anesthesia. While the regional cerebral oxygen saturation (rSO2) and blood volume index (BVI) were determined continuously, each patient received the drug at dose of 0.08 mg.kg-1.h-1 initially, and after 15 minutes, the dose was increased by 0.08 mg.kg-1.h-1 at a time. This was repeated until the dose reached 0.40 mg.kg-1.h-1. At every dose level, rSO2 and BVI were determined, and the dose response relationship was obtained. We found that nicorandil also produces cerebral arterial dilation under clinical conditions. PMID- 9369044 TI - [Hemodynamic effects of continuous epidural infusion with local anesthetics]. AB - Epidural blockade with local anesthetic may cause hypotension resulting from sympathetic block and/or systemic effect produced by absorbed local anesthetic through epidural blood vessels. In the present study, we compared the hemodynamic effects of saline 0.5 ml.h-1, lidocaine 0.5 ml.h-1, bupivacaine 0.5 ml.h-1, lidocaine 2 ml.h-1, and bupivacaine 2 ml.h-1, which were given epidurally combined with morphine. There was not significant difference in hemodynamics among 5 groups. Continuous epidural infusion with a small dose of local anesthetic agent combined with morphine is unlikely to induce apparent hemodynamic effects during postoperative period. PMID- 9369045 TI - [Diastolic function in patients with coronary artery disease before and after CABG]. AB - We evaluated diastolic cardiac function in 16 patients with coronary artery disease before and after coronary angioplasty using transesophageal echocardiography. Peak early diastolic and late diastolic filling velocities (E wave and A wave) and velocity time integrals of early and late diastolic filling (VTI-E and VTI-A) were measured by pulsed doppler echocardiography. The patients were divided into two groups: Group A; E/A > or = 1. Group B; E/A < 1. There were statistical differences between the two groups in E-acceleration time and VTI 0 33%/ total VTI at pre-coronary angioplasty period (P < 0.05). There were statistical differences in E-decelaration time and E-decelaration slope of group B before and after coronary angioplasty (p < 0.05). These results suggest that the left ventricular diastolic function in group B has recovered partly at one hour after coronary angioplasty. PMID- 9369046 TI - [Low flow anesthesia using a fresh gas flow of 600 ml.min-1 for 5 hours]. AB - Low flow anesthesia (LFA) using a fresh gas flow (FGF) of 600 ml.min-1 with oxygen and nitrous oxide flow each set at 300 ml.min-1, and dial setting of sevoflurane 3% was administered to 30 patients for a duration of 5 hours. There were no problems such as unsuitable concentrations of nitrous oxide and sevoflurane in inspired and expired gases or low FIO2 below 0.3 during anesthesia in 15 patients of group A. Their body weight was 53 +/- 5 kg. FIO2 decreased below 0.29 at about 4 hours in 7 patients of group B weighing 62 +/- 6 kg, and at about 1 h in 8 patients of group C weighing 71 +/- 7 kg. In group A and B, the sum of concentrations of oxygen, nitrous oxide and sevoflurane in inspired gas decreased for a moment and recovered as anesthesia progressed, but in group C, it kept decreasing without recovery. The body weight was significantly different among the 3 groups (P < 0.05). It was suggested that in group A the FGF per body weight was suitable; in group B though oxygen flow was larger than oxygen consumption, hypoxia occurred due to saturation of nitrous oxide in the body; and in group C the FGF was insufficient. The compound A was detected in the breathing circuit, and the concentration was around 20 ppm and it did not depend on the duration of LFA. It was concluded in this study that LFA using the FGF of 600 ml.min-1 with setting of 3% sevoflurane, 50% oxygen and nitrous oxide, could be performed safely without risks such as hypoxia and severe delay of induction for patients weighing 53 +/- 5 kg for a duration of 5 hours. PMID- 9369047 TI - [Antinociceptive activity of intracisternal clonidine in the mouse]. AB - The antinociceptive activities of clonidine have been determined against three qualitatively different noxious stimuli in the mouse. The methods used to evaluate this activity were selected to include tests which employ different types of noxious stimuli, i.e. heat (hot plate), chemical (acetic acid-induced writhing) and mechanical (tail pinch). Test drug and control treatments were given by cisternal injection in a dose volume of 10 microliters.mouse-1. The results presented here show that clonidine has potent antinociceptive properties against several types of noxious stimuli. Clonidine produced steep dose-response lines in all tests. The response to the writhing assays were completely inhibited by 1.0 microgram.mouse-1 of clonidine. In contrast in both the hot plate and tail pinch assay, however, clonidine did not produce a consistent antinociceptive effect at a dose of 200 micrograms.mouse-1. Utilizing these three different types of assays, the rank order of antinociceptive potency for clonidine in different noxia was the writhing >> hot plate > tail pinch. It was concluded from these results that clonidine has potent antinociceptive properties against chemical visceral stimuli. PMID- 9369048 TI - [Serum and urinary magnesium during and after cardiac surgery]. AB - To investigate the effects of cardiopulmonary bypass (CPB) on the serum magnesium (Mg) level, we observed the perioperative changes in serum and urinary Mg in 20 patients undergoing open heart surgery. The serum Mg was in the normal range (mean +/- SE, 1.98 +/- 0.04 mg.dl-1) at the induction of anesthesia, and began to fall during CPB, reaching its lowest level (1.43 +/- 0.05 mg.dl-1) on the first postoperative day, and returned to normal level on the second postoperative day. We found a good correlation between the decrease in serum Mg and increase in urinary Mg excretion, suggesting that the decrease in serum Mg level may be attributed to the increase in urinary excretion of Mg. But, compared to the increase in urinary loss of Mg, the observed decrease in serum Mg on the first operative day was not as great as expected. Furthermore, the level of serum Mg returned to normal spontaneously on the second operative day. These observations suggest that Mg was transferred from the intracellular to the extracellular compartment during and after CPB. PMID- 9369049 TI - [Effect of controlled hypotension induced by prostaglandin E1 on evoked spinal cord potential and spinal cord blood flow]. AB - We evaluated the effect of controlled hypotension induced by PGE1 on evoked spinal cord potential (ESCP) and spinal cord blood flow (SCBF) in 14 patients undergoing laminectomy or laminoplasty. They were divided into two groups: hypotensive group (group H), non-hypotensive group (group N). Controlled hypotension was induced with PGE1 to maintain mean arterial blood pressure at 55 60 mmHg for 45 min. The amplitude and latency of the N 1 potential were analyzed, and the SCBF was estimated by laser doppler flowmeter. There were no significant differences in ESCP and SCBF. These results suggest that controlled hypotension by PGE1 maintained normal local spinal cord blood flow autoregulation. PMID- 9369050 TI - [The effects of premedication on induction doses of propofol and hemodynamic responses during induction]. AB - We chose five sedatives for premedication and investigated the effect of these drugs on the induction doses of propofol. One hundred patients were allocated into one of five groups of 20. These groups consisted of control group (C) given only atropine 0.5 mg i.m.; CL group (plus clonidine 0.15 mg orally); H group (plus hydroxyzine 25 mg i.m.); M group (plus midazolam 3 mg i.m.) and D group (plus diazepam 10 mg orally). The induction dose was measured using loss of count technique. Arterial pressure and heart rate were measured, before and after propofol induction as well as after intubation. We also calculated rate pressure products (RPP) at each point. The induction doses were significantly lower in M group than those in C-group. On the other hand, in hemodynamic responses, RPP was unchanged in any groups after propofol induction and after the intubation. Both propofol and midazolam have been known to have a depressive effect on the central nervous system via GABA-A receptor-mediated inhibition, although the exact receptor for propofol is unknown. We thought, therefore, that when the interaction occurred, both midazolam and propofol had the same effect on the GABA A receptor and increased chloride ion flux through the channels. Hydroxyzine and clonidine, however, do not share a common receptor or exert effect on the GABA-A receptor. We consider that this was one of the reasons why induction doses of both H and CL group could not decrease significantly. We concluded that midazolam 3 mg decreased propofol induction dose significantly. Both midazolam 3 mg and clonidine 0.15 mg decreased RPP before induction and hemodynamic responses to induction and intubation were stable. PMID- 9369052 TI - [Efficacy of ring-shape cover in active skin surface warming in neonates--a retrospective comparative study with conventional methods]. AB - Prevention of perioperative hypothermia is one of the most essential factor for neonatal anesthesia. Recently the forced-air warming system has been considered the most effective method in preventing perioperative hypothermia in adults, in children, and in infants during maxillofacial operations. However, its use for abdominal or thoracic surgery in neonates has not been examined. In the present study, we studied the effects of the forced-air warmer with a ring-shape cover, and compared this method with the conventional method retrospectively. PATIENTS AND METHODS: Sixteen neonates, 13 for abdominal and 3 for thoracic surgery were anesthetized with oxygen-air (nitrous oxide) sevoflurane (isoflurane or enflurane) in combination with/without fentanyl. They were divided into two groups; one for forced-air warming (F-group), and another for conventional methods (C-group). The patients' mean age, height and weight, the duration of anesthesia, infusion rate (ml.kg-1.hr-1), and urine output did not differ each other. Patients in F-group were placed in the center of the ring-shape cover and received heated air from their surroundings. We did not use any other warming equipment or means except for an artificial nose and a warming mattress. "Medium" heated air (38 degrees C) or unheated, room temperature air were used when necessary. The operating room temperature was kept around 25 degrees C. Patients in the C-group were placed on a warming mattress and under an infrared radiant heater with the room temperature of 30 degrees C. Their extremities were covered with aluminum-foil. Rectal, deep forehead, and deep sole temperatures were monitored throughout anesthesia. RESULTS AND CONCLUSION: In F-group, temperatures were well maintained, while C-group failed to maintain. In F-group, the mean value of base excess at the beginning of the operation was -1.8 mM, but it was restored to normal level without administration of sodium bicarbonate. No complications were found. Thus, compared to conventional methods, the forced-air warming system with a ring-shaped cover is an efficient method for body temperature management in neonatal anesthesia. PMID- 9369051 TI - [Hyperalgesia induced by intrathecal administration of nitroglycerin involves NMDA receptor activation in the spinal cord]. AB - Spinal NMDA receptors are involved in hyperalgesia and chronic pain. The activation of spinal NMDA receptor results in the production of nitric oxide in the second order neurons in the spinal cord dorsal horn. We investigated the effects of intrathecally administered nitroglycerin (NTG) which releases nitric oxide in the cell. Formalin test which reflects phasic and tonic nociception was used as a nociceptive measure in rats with chronically implanted intrathecal catheters. Intrathecal injection of NTG resulted in the increase of flinching behavior induced by formalin injection to one paw in phase 1 (phasic) and phase 2 (tonic) responses in a dose-dependent manner. Intrathecally administered NMDA antagonist, MK-801 (MK) dose-dependently inhibited the effect of NTG but the effect was significant only in the phase 2 of the formalin test. MK given after formalin injection had significantly less effect on the phase 2 response. L-NAME (NOS inhibitor), MB (guanylate cyclase inhibitor) and HB (nitric oxide scavenger) significantly antagonized the hyperalgesic effect of NTG in the phase 2 of the formalin test. These results show that nitric oxide plays an important role in producing hyperalgesia in the spinal cord acting postsynaptically as well as pre synaptically. PMID- 9369053 TI - [The optimum time interval for applying lidocaine containing adhesive tape is 6 to 8 hours for venipuncture pain relief]. AB - Lidocaine containing adhesive tape (LT) is a pressure sensitive adhesive tape which contains 60% of lidocaine in base form. We investigated the optimum time interval for applying LT for venipuncture pain relief by using visual analogue scale (VAS). Six hundred seventeen cases were prospectively divided into 0.5, 1, 2, 3, 4, 6, 8, 12 hour groups. LT was applied on the dorsum of the hand and the vein was punctured with a 20 gauge polyurethane catheter (Insyte TM: Becton Dickinson, USA). The level of pin prick sensation was reduced in accordance with the duration of LT application. While the median of the pin prick sensation level was below 5% of control in the longer than 6 hour groups, the 90 percentile was 30% and 60% in 6 hour and 12 hour group, respectively. This suggested a possible poor skin contact of LT in the 12 hour group. VAS of venipuncture pain was significantly improved as the duration of LT application increased. When the punctures was smooth the median values of VAS in 6 and 8 hour groups were both less than 5%. Even with rough venipuncture, significant pain relief was observed in longer than 3 hour groups. We concluded that 6 to 8 hour applying of LT was optimum for pain relief of venipuncture. PMID- 9369054 TI - [A malpositioned CVP catheter]. AB - A 2-year-old boy was scheduled for patch closures of ASD and VSD. After anesthesia induction, infection of a double lumen central venous catheter (5 Fr, Arrow) was tried into the superior vena cava through the right jugular vein by Seldinger's method. We confirmed the placement of the catheter by drawing a small amount of blood. After the operation, chest X-ray examination in ICU revealed the misplacement of the catheter into his right intrapleural space. The catheter was left overnight to be used as a drainage route of a possible bleeding. Next morning, no abnormal finding in his chest X-ray and stable circulatory and respiratory conditions were found and we proceeded to extubate his endotracheal tube and take away the catheter. Two hours after the removal of the catheter, the boy showed forced respiration. He became cyanotic rapidly and then he needed emergency intubation. Following chest X-ray examination and an aspiration of intrapleural space revealed a severe hemothorax of the right side, where catheter had been inserted. The boy recovered without any disorders. This case suggests the importance to confirm the placement of CVP catheter, and to prevent the possible complications due to the malpositioned catheter. PMID- 9369055 TI - [A case of severe bronchospasm under epidural anesthesia with fentanyl]. AB - A case of severe bronchospasm under epidural anesthesia with fentanyl was described. The etiology of the bronchospasm may not have been related to sympathetic nervous blockade, histamine release, or anaphylaxis. In an asthmatic patient, it should be noted that epidural anesthesia with fentanyl could develop bronchospasm. PMID- 9369056 TI - [A case of aortic dissection after the termination of cardiopulmonary bypass]. AB - We report, a case of aortic dissection after the termination of cardiopulmonary bypass (CPB), which was diagnosed by transesophageal echocardiography (TEE). A 70 year old male with aortic regurgitation received aortic valve replacement. After the termination of CPB, the aortic dissection was diagnosed by TEE. Furthermore wall motion abnormality was found by TEE, and aorto-coronary bypass was performed after observation by TEE. This case report suggests that TEE is useful not only for diagnosis but also for therapeutic orientation of aortic dissection. PMID- 9369057 TI - [Where is a leak point detected by "the low flow leak test" of anesthetic machines?]. AB - "The low flow leak test" is recommended for pre-anesthetic inspection of anesthetic machines. We carried out anesthesia compression tests as a standard. Even in that case, often the low flow leak test does not meet the standard. We investigated the point where there is a leak in the anesthetic machine. Observing the leak that fluctuates each time there is detachment or attachment of the canister, the primary cause of the leak is thought to be related to the canister. It is important to carry out an inspection of the canister if the low flow leak test does not meet the standard. PMID- 9369058 TI - [Medical and social aspects of refractive corneal surgery]. PMID- 9369059 TI - [The effect of tranilast on subepithelial corneal opacity after excimer laser keratectomy]. AB - Recent studies have reported that tranilast inhibited in vitro the proliferation of keratocytes from corneal subepithelial opacities (haze) and collagen synthesis in cultured corneas after excimer laser photorefractive keratectomy (PRK). In this study 0.5% tranilast eye drops, 0.1% betametazone phosphate eyedrops, and a 0.5% tranilast base solution (control) were administered four times daily to rabbits which had undergone PRK. Weekly evaluation of the inhibitory effect of these drugs on haze began two weeks after surgery according to Fantes' classification. 0.5% tranilast suppressed haze from six weeks to thirteen weeks after PRK (p < 0.05). 0.1% betametazone phosphate showed no effect. These results suggested that 0.5% tranilast had a satisfactory therapeutic effect on haze after PRK. PMID- 9369060 TI - [Effects of the age on the apoptotic and proliferative reactions in the constant light-exposed rat retina]. AB - The effects of age (5-3 weeks old) on apoptotic changes in the rat photoreceptor cells induced by 3 days of constant light exposure were examined using TUNEL (TdT mediated dUTP nick end labeling). The effects on the expression of the Ki67 antigen, which is a proliferative marker, in these photoreceptor cells were also examined by immunohistochemistry. The results suggested that the number of positive cells in the outer nuclear layer of the superior hemisphere is higher than in the inferior nuclear layer in both the TUNEL reaction and the distribution of the Ki67 antigen, and that the number of positive cells increases with age in general. The cells of monocytes/macrophages may locally proliferate in the retina to phagocytose the apoptotic bodies owing to the degeneration of photoreceptor cells. The present findings revealed that the rates of these reactions may generally increase with age. PMID- 9369061 TI - [Histological examination of lymphoid follicles in conjunctiva-associated lymphoid tissue in guinea pigs--Report 1. Histological characteristics of follicular dendritic cells]. AB - We histologically examined the existence of follicular dendritic cells (FDCs) in the follicular area of conjunctiva-associated lymphoid tissue (CALT). Animals used in the experiment were Hartley guinea pigs sensitized with a topical application to the eyes of an emulsion of a mixture of ovalbumin and Freund's complete adjuvant in equal amounts. The animals were divided into 4 groups: a group with no eye drops administered (Group A), a group examined 1 week after administration of eye-drops (Group B-1), a group examined 2 weeks after administration (Group B-2), and a group given booster administration of eye-drops (Group C). These animals were examined by methyl green pyronine staining, alpha naphthylacetate esterase staining, and enzyme-antibody methods against S-100 protein or major histocompatibility complex class II (MHC class II) antigen. Also peroxidase-anti-peroxidase (PAP) was applied to the eyes and the uptake of PAP in CALT was observed histologically. In each group, positive reticular stains to alpha-naphthyl-acetate esterase staining and S-100 protein were found in the CALT follicular area. The positive cells were found to be dendrite cells by immunoelectron microscopy. An uptake of PAP was seen in the CALT follicular area, suggesting the function of trapping and holding the antigen-antibody complex by FDCs. It was concluded that dendritic cells present in the follicular area of CALT were FDCs. PMID- 9369062 TI - [Histological and ultrastructural study of corneal endothelium after excimer laser ablation in rabbit]. AB - To investigate the effect of excimer laser ablation on the corneal endothelium in the early period, an excimer laser ablation was performed on rabbit cornea. Electron microscopy revealed an irregular space in the endothelial membrane facing Descemet's membrane 48 hours after the laser ablation. At 60 hours, electron-dense material was observed between the endothelial cells and Descemet's membrane. At 72 hours, electron-dense material was observed in Descemet's membrane, but no morphologic change was observed in the endothelium. These results suggest that excimer laser ablation may affect reversible corneal endothelium and it is important to perform a long-term follow-up of the corneal endothelium after excimer laser ablation in humans. PMID- 9369063 TI - [Posterior segment complications after macular hole surgery]. AB - Fifty-three patients with stage III or stage IV idiopathic macular holes who underwent vitrectomy were reviewed. Posterior segment complications were noted in 20 (38%) of patients. These included peripheral retinal breaks (21%), peripheral visual field loss of unknown etiology (8%), rhegmatogenous retinal detachment caused by peripheral retinal break (6%), late reopening of the hole (4%), and retinal pigment epithelium loss under the hole (4%). The final visual acuity was two lines or more worse than preoperative visual acuity in 10% of these complicated eyes and in 9% of eyes without posterior segment complications. Patients with peripheral retinal breaks or retinal detachment had significantly shorter duration of macular hole symptoms (p < 0.01) than those without these complications. Posterior segment complications after vitrectomy for macular hole appear to be more common than expected, but the effect of such complications on final visual outcome was not significant. PMID- 9369064 TI - [Clinical aspects of Behcet's disease--epidemiological features and visual prognosis]. AB - Behcet's disease patients who visited the eye clinic of Tokyo University Hospital during the past 20 years were surveyed retrospectively, and their epidemiological features and visual prognosis were demonstrated. We evaluated the number of patients, sex ratio, age of onset, ratio of complete type to incomplete type, and ratio of major symptoms other than the ocular manifestation. The results showed a tendency similar to the results of the nationwide hospital survey in Japan. We also evaluated the visual prognosis of Behcet's disease patients in our clinic by the least square method. In the groups of patients whose visual acuity at the initial visit was over 0.4, the visual prognosis of those who visited from 1984 till 1993 was significantly better than that of those who visited from 1974 till 1983. The use of cyclosporine was presumed to be one of the most important factors in the improved visual prognosis of Behcet's disease patients in our clinic. PMID- 9369065 TI - [Study on risk factors for central visual field loss in advanced open angle glaucoma]. AB - 53 eyes of 53 advanced open angle glaucoma (stage 5 of Aulhorn-Greve's classification) were studied regarding the risk factors for central visual field loss by the Cox proportional hazards model. The cases of foveal threshold under 20 dB were defined as central visual field loss group (9 eyes), and the cases over 20 dB were defined as no visual field loss group (44 eyes). The following clinical factors were statistically analyzed between the two groups: gender, age, family history of glaucoma, refraction, intraocular pressure, blood pressure, visual field measured by static perimetry, optic disc, retinal nerve fiber layer, treatment, and systemic disease. Foveal threshold, mean deviation, pattern standard deviation, corrected pattern standard deviation, and retinal nerve fiber layer defect showed significant difference between the two groups, and diastolic blood pressure and diastolic blood pressure minus intraocular pressure showed a tendency to be related. From the results obtained, intraocular pressure and these other clinical factors should be considered for the management of advanced open angle glaucoma patients. PMID- 9369066 TI - [Four cases of persistent hyperplastic primary vitreous]. AB - We evaluated four cases of persistent hyperplastic primary vitreous (PHPV) encountered at Nagoya City University Hospital in 1995. PHPV was seen unilaterally in three cases and bilaterally in one. The series comprised two males and two females, ranging in age from three to eight months, with an average of 4.8 months. Case 1 had a white strand running from the optic disc to the posterior surface of the lens in the left eye. Case 2 showed leukocoria in the right eye and central corneal opacity in the left. Magnetic resonance imaging (MRI) revealed total retinal detachment in both eyes. Case 3 exhibited retinal folds running from the optic disc to the posterior surface of the lens in the left eye. Case 4 showed elongation of the ciliary processes and leukocoria in the right eye. Ipsilateral total retinal detachment was seen in MRI. Three eyes of two cases were microphthalmic. Associated ocular anomalies included, posterior embryotoxon, sclerocornea, hypoplasia of the iris stroma and peripapillary staphyloma. There were accompanying systemic anomalies such as arachnoidal cyst, syndactyly, microcephalus, heart anomalies, pulmonary atresia and asplenia. Patients with PHPV should be carefully examined for the possible presence of other ocular and systemic anomalies caused by neural crest disorders. PMID- 9369067 TI - [A case of infiltration of scar of sarcoidosis after blepharoplasty]. AB - A case of a 28-year-old woman with infiltration of sarcoidosis scar tissue after blepharoplasty is reported. Nodules developed two times in her right upper eyelid about 1 and 2 years after blepharoplasty of both eyes and they were resected each time, but eruption recurred. Ophthalmic examination revealed aqueous flare and cells, snowball vitreous opacities, and retinal periphlebitis. A chest X-ray disclosed bilateral hilar lymphadenopathy (BHL). Laboratory studies showed an elevation of the serum angiotensin converting enzyme (ACE). Light microscopy revealed epithelioid granuloma with no caseation necrosis in a biopsy specimen, Viewing through polarized light demonstrated crystalline-like foreign bodies with bi-refringence in the epithelioid granuloma. Electron microscopic X-ray microanalysis confirmed these foreign bodies to be composed of Si, Mg, and O. These findings indicate that this skin lesion was caused by an infiltration of sarcoidosis scar tissue. PMID- 9369068 TI - [Thrombopoietin is a multifunctional factor]. AB - Thrombopoietin (TPO) is the critical regulator of proliferation and differentiation of megakaryocytic lineage. TPO has potent stimulatory effects on platelet production in patients with chemotherapy-induced thrombocytopenia. In addition to sustaining megakaryocytopoiesis, TPO may play an important role in regulating neutrophil activation and erythropoiesis. Furthermore, TPO induces proliferation of acute myeloblastic leukemia cells in vitro in some cases. These results suggest that TPO may be multifunctional factor. Recently osteosclerosis is observed in TPO transgenic mice. To determine whether TPO can modulate the osteoclastic differentiation from hematopoietic stem cells, we investigated the effect of TPO on in vitro osteogenesis. TPO inhibited the formation of osteoclastic cells and decreased the areas of bone resorption pits in a dose dependent manner. We examined whether transforming growth factor-beta (TGF-beta) and platelet derived growth factor (PDGF), major cytokines produced by megakaryocytes, mediate the inhibitory effect of TPO. The addition of either anti TGF-beta or anti-PDGF antibody to bone marrow cell cultures completely antagonized the effect of TPO on osteoclastogenesis. These data suggest that TPO inhibits osteoclastogenesis by stimulating thrombopoiesis and that TGF-beta and PDGF mediate the effect of TPO by impacting macrophage-lineage cells as osteoclast precursors. PMID- 9369069 TI - [Shear stress and platelet-derived microparticles]. AB - One of the responses of activated platelets to certain stimuli is the shedding of microparticles. Many studies have attempted to characterize the role of microparticles under various clinical situations or experimental conditions. Pathological levels of fluid shear stress may occur in diseased small arteries and arterioles partially obstructed by atherosclerosis or vasospasm and such shear stress may induce the activation and aggregation of circulating platelets. We investigated whether high shear stress could cause both platelet aggregation and shedding of microparticles from the platelet plasma membrane. A cone-plate viscometer was used to apply shear stress and microparticle formation was measured by flow cytometry. It was found that microparticle formation increased as the duration of shear stress increased. Both microparticles and remnant platelets showed procoagulant activity on their surfaces. Investigation of the mechanisms involved in shear-dependent microparticle generation showed that binding of von Willebrand factor to platelet glycoprotein Ib, influx of extracellular calcium, and activation of platelet calpain were required to generate microparticles under high shear stress conditions. Activation of protein kinase C promoted shear-dependent microparticle formation. These findings suggest that local generation of microparticles in atherosclerotic arteries, the site at which pathological levels of shear stress could occur, contributes to arterial thrombosis by providing and expanding a catalytic surface for the coagulation cascade. PMID- 9369071 TI - [Information on von Willebrand disease]. AB - The revised classification of von Willebrand disease (VWD) was approved by the International Society of Thrombosis and Haemostasis (ISTH)/SSC in 1993. It consists of three major categories : quantitative defect in type 1, qualitative defect in type 2, and complete deficiency in type 3. Type 2 has four subtypes : decreased GPIb binding with deficient larger multimer of VWF in type 2A, excessive GPIb binding in type 2B, defective GPIb binding with larger multimer in type 2M, and defective FVIII binding in type 2N. Subsequently, criteria for diagnosis of VWD is being reconsidered by the association. Therefore, we introduced the guidelines for diagnosis of VWD type 1 and type 2N in our department. PMID- 9369070 TI - [Detection of anti-GPIIb-IIIa autoantibodies and its clinical significance in autoimmune thrombocytopenic purpura]. AB - Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by thrombocytopenia due to antiplatelet autoantibodies. It has been demonstrated that the platelet glycoprotein (GP) IIb-IIIa and/or GPIb-IX are major target antigens for the autoantibodies in this disorder. Diagnosis of ITP has usually been based on clinical criteria. However, development of reliable immunological techniques enable us to make a diagnosis of "autoimmune thrombocytopenic purpura" in some patients. In this paper, we review the immunological techniques such as immunoblot assay, immunoprecipitation assay, and modified antigen capture ELISA, and discuss the clinical significance of the detected anti-GPIIb-IIIa auto antibodies. PMID- 9369072 TI - [Effect of thrombolytic agents on platelets and blood coagulation system]. AB - The effect of tissue-type plasminogen activator (tPA) on platelet aggregation and blood coagulation was investigated. Collagen-induced platelet aggregation in washed platelet suspension was significantly inhibited by the addition of tPA, but the effect was limited when platelet rich plasma was used instead of washed platelets because of the presence of alpha 2-antiplasmin in plasma. The diluted prothrombin time was significantly shortened by the addition of tPA to normal plasma, and although the levels of molecular markers of thrombin formation were increased compared to that of normal controls, the increase was diminished when factor VII-deficient plasma was used, suggesting that tPA enhances factor VII. The activated factor VII concentration was significantly increased by the addition of plasmin to factor VII solution. These findings suggest that tPA enhances the coagulation system by factor VII activation through the generation of plasmin in normal plasma. This enhancing effect of tPA on coagulation system may be partly related to vascular reocclusion after thrombolytic therapy. PMID- 9369073 TI - [Management of errors in hospital laboratories--Total Quality Control and lists]. AB - Errors in the daily routine work of a hospital laboratory vary. Therefore, measures to prevent errors must be devised. It is important to perform Total Quality Control (TQC) and to provide reliable diagnostic information and this does not stop at quality control of mere assay value, but extends to consideration of the correspondence to a patient. It is absolutely necessary to reduce errors in a laboratory and to perform TQC steadily. Therefore, the concept of TQC is divided roughly as follows 1) Safe management, 2) Technical management, 3) Information management, 4) Materials management. These categories are then subdivided even further. These categories relate to error management because it is considered that the manuals for technical and information management are important. It is necessary to create an error processing ledger to collect information for error management for TQC and for prevention of errors in investigating causes and to record all processes according to the contents of the error. Such records can be used to prevent recurrences. Thereby, not only prevention of errors but also improvements in the accuracy and reliability of information offered are thought to become possible. PMID- 9369074 TI - [Quality assurance for the measured values and quality control]. AB - It is essential for us to build a liable quality control system in order to report excellent results assured of quality. For the purpose, not only the execution of quality control on laboratory side but also the recognition of quality control on clinical side are important. And more important matter is to record the error of measured values. PMID- 9369075 TI - [Responses to customer complaints at commercial laboratories]. AB - For commercial laboratories, one of the routine duties involves responding to various kinds of inquiries and complaints received from customers. As causes of complaints, lack of communication between the laboratory and customer, and test errors were considered. In this paper, complaints received by our laboratory were collected and classified by content, and measures to prevent test error are reported. We think the complaints contain important information that can be used to improve the quality of our laboratory. We hope that reinforcement of communication with customers and promoting test knowledge among the customers can produce more clearly worded complaints which will provide more valuable information. We try to receive and deal with these complaints seriously. PMID- 9369076 TI - [One of the procedure for quality control]. AB - It goes without saying that assurance of quality control in a clinical laboratory is the most essential factor which can be easily influenced by how medical support is practiced. In recent years, the appreciation of a narrow sense of quality control in analysis has become the central focus. These days, however, we are seeing that reports of examinations have been submitted to doctor with mistake which come in stages from the patient's materials for examinations to making the report. We have not only cleared up the cause but we have also checked our work on these kinds of faulty reports and thought of measures for mistake in putting them to practical use. Moreover, as we have developed the laboratory system with full-time staff in our institution, we have been able to take advantage of this kind of problem to accomplish our laboratory work. To avoid a mistake, comprehension and collaboration of MD and co-medical staff is required. To ensure this end, it is also required that we usually communicate with an MD and nurse. It is possible that our carelessness cause us to make mistake in our work such as bleeding examination after usual hours. These examinations are based on a basic line of sharing this sort of work with all staff. In future, we aim for laboratory examination to permeate not only in a laboratory but also in the whole hospital. PMID- 9369077 TI - [Prevailing conditions and problems with blood transfusion tests as seen after analysis of Osaka Medical Association Survey]. AB - We have analysed the results of the 1996 Osaka Medical Association Clinical Examination Quality Control survey. The number of participating clinical laboratories was 257 for ABO blood group system, 255 for Rh (D) antigen, and 250 for crossmatching. Five (5) clinical laboratories (1.9%) determined the ABO blood group by the antigens on red blood cells test only, and three (3) clinical laboratories (1.2%) showed errors when using antibodies in serum test. On the Rh(D) antigen tests, fifteen (15) clinical laboratories (5.9%) showed negative results without carrying out an antiglobulin test. Three (3) clinical laboratories (1.2%) were unable to detect the anti Dib antibody which showed 1:256 titerates using the antiglobulin test method. Moreover, it was apparent that thirty-four (34) clinical laboratories (13.6%) had problems with the test standards and other technical points, and further, two (2) clinical laboratories (0.8%) reported contradictory results due to confusing blood samples of donors and patients to be transfused. As a result, we consider it very important for preventing blood transfusion accidents that any technician carrying out blood transfusion tests makes correct decisions and determinations based on accurately performed test methods, and that a manual be prepared to avoid technical and administrative errors and that this manual be followed to the letter. PMID- 9369078 TI - [Gene testings in relation with gene diagnosis and therapy]. AB - Recent advances in the molecular biology research have devoted greatly to the clinical applications of genetic informations. Gene diagnosis and therapy is a new medical field to deal with these applications. Nowadays diseases related with gene abnormalities have been shown to reach 8,450, and gene testings to cover all these should be very wide and variable. So that any one of the clinical laboratories in a hospital or even research institutes and laboratory centers should not be able to handle all the testings. A model system to promote gene testings effectively in Japan, which includes a special department in a hospital and limited specifications to the individual laboratories or centers, were presented. In the case of monogenic genetic disorders, gene testing results are useful not only to confirm clinical diagnosis but to predict future development of disorders preclinically and even during the prenatal or pregestational period. Accordingly, these may evoke critical ethical and social problems. Many of common diseases are polygenic in nature and gene testings in these disorders are not directed to the diagnosis but are quite useful to see the individual characteristics of the patients related to the special phenotypes or even the fate of disease process. Acquired malignancies are known to be resulted from a somatic gene mutation and progress by the associations of further abnormalities. Only limited gene testings are already now in use. Wide future development in this field is expected after getting detailed meanings of gene testings in the individual cancers. Gene testings for infectious diseases are known to be quite effective on the early and accurate diagnosis, and many of these are already covered by the health insurance. In conclusion, gene testings are quite important but variable and laboratory personnel should not be able to deal all of these properly. Considering future development of gene therapy, rapid establishment in a hospital of a special department, Department of Gene Diagnosis and Therapy, which is consisted from 3 divisions such as genetic counseling, gene testing and management, and monitoring and adviser of gene therapy, is highly recommended. PMID- 9369079 TI - [Current problems in quality control (QC) in hematology]. AB - Total quality control (TQC) is one of the most important issues in laboratory hematology. As for complete blood count (CBC), almost all blood cell counters possesses quality control (QC) programs for its determination, and values of high quality can be provided by the counters. Reticulocytes can be determined precisely as well. However, mean cell volume (MCV) were slightly different among blood cell counters when semifixed QC materials were used for its surveillance. No QC materials to evaluate white cell differential functions have not be found for the common use now. Thus, urgent matter would be the development of appropriate QC materials to be used for overall blood cell counters. In coagulation testings, trials for common use of international normalized ratio (INR) for the prothrombin time (PT) test has been continued yearly due to the varieties of biophysical characteristics among PT reagents. Similar variation are also present among activated partial thromboplastin time (APTT) reagents. Some improvement would be required. PMID- 9369080 TI - [Serum soluble CD8 and soluble interleukin-2-receptor levels during interferon therapy in chronic hepatitis C]. AB - We examined the relationship between the changes of serum soluble CD8 (sCD8) and soluble interleukin-2 receptor (sIL-2R) levels and effectiveness of interferon (IFN) in patients with chronic hepatitis (CH) C. Changes in sCD8 levels were parallel with fluctuations of alanine aminotransferase (ALT) in CH patients during IFN treatment but decreases of sCD8 levels were slower than those of ALT. In IFN effective and ALT decreased patients sCD8 levels is also decreased. sIL-2R levels was increased transiently during administration of IFN in most cases. It was suggested that decrease in sCD8 levels is indicative of the effectiveness of IFN therapy. PMID- 9369082 TI - [Report of the Immunity and Infectious Diseases Research Liaison Committee, the Seventh division, Science Council of Japan--For the establishment of infection control]. PMID- 9369081 TI - [Coronary circulation-derived plasma in patients with vascular restenosis stimulates the growth of coronary artery smooth muscle cells in culture]. AB - To clarify the role of locally secreted humoral factors in coronary restenosis after percutaneous transluminal coronary angioplasty (PTCA), we studied the effects of coronary circulation-derived plasma from patients with and without restenosis on the growth of coronary artery smooth muscle cells (CASMC) in culture. Specific coronary plasma-dependent growth stimulation/inhibition of cells (CASMC and human umbilical venous endothelial cells) was estimated by subtracting the stimulatory activity, determined by bromodeoxyuridine incorporation, of the pre-coronary plasma from that of the post-coronary plasma. Coronary-specific plasma from five patients with restenosis showed a stimulatory effect on the growth of CASMC, whereas that from four patients without restenosis showed an inhibitory effect. On the other hand, they showed the opposite effects on the growth of endothelial cells. These findings suggested that the local environment is closely associated with the development of restenosis and may play a crucial role. Analysis of coronary circulation-derived plasma may facilitate clarification of the mechanism of restenosis. PMID- 9369083 TI - [Information processing deficits in depression in terms of event-related potentials: in comparison with schizophrenics and normal controls]. AB - Information processing deficits characteristic of remitted major depression, which may be a vulnerability marker for the disease, were examined from two aspects by means of visual event-related potentials (ERPs) obtained during simple and discriminative response tasks: 1. To clarify the difference in cognitive dysfunction between both depressives and schizophrenics in remission, we compared the ERPs in remitted depressive patients (n = 11) and remitted schizophrenic patients (n = 9) with those of age, and sex-matched controls (n = 10). 2. To clarify the influence of aging on information processing in remitted depression, ERPs in young remitted depressives (20-46 years old, n = 11) were compared with those in older remitted depressives (52-75 years old, n = 11) in contrast to young (n = 10) and older (n = 11) controls. The remitted schizophrenics showed a retardation in NA and N2 latencies and a reduction in P3 amplitude. However, P1 increased in amplitude exclusively in the remitted depressives. The effect of stimulus discrimination on N1 seen in the controls was absent in both patient groups. The results suggest that the remitted depressives had an attentional deficit in early information processing reflected on P1 and N1 potentials, while the remitted schizophrenics had an extensive cognitive dysfunction reflected on N1, NA, N2, and P3 potentials. Although the effect of stimulus discrimination on N1 was absent in both young and older remitted depressive patients, older patients showed no effects of normal aging on ERPs such as P1 increase or N1 increase during discrimination tasks. Significant interaction effects between diagnosis and aging were found by ANOVA only in the laterality of the P1 amplitude. Older remitted depressives showed an unbalanced right-predominance in P1 amplitude. These results suggest that older remitted depressives had the same early information-processing deficit seen in the young remitted depressives as well as an overactivation over the right hemisphere in the attentional mechanism, irrespective of normal aging. PMID- 9369084 TI - [Apolipoprotein E genotype as a risk factor in Japanese patients with early-onset and late-onset Alzheimer's disease]. AB - Recent studies have provided evidence of an association of apolipoprotein E (apoE) epsilon 4 allele and late-onset sporadic Alzheimer's disease (AD). Some studies have shown the possibility that apoE epsilon 4 is a risk factor of developing AD in early-onset type. We have analyzed the apoE gene polymorphism in a sample of 310 Japanese AD subjects and 237 age-matched Japanese controls. We divided the sporadic AD patients into two subgroups of 237 late-onset (> 65 years) and 73 early-onset (< or = 65 years) patients, and into three subgroups according to their apoE genotype, no epsilon 4, one epsilon 4, and two epsilon 4 alleles. Our data confirmed an association between epsilon 4 allele and early onset AD and late-onset AD. The odds ratios (95% confidence interval) referred to no epsilon 4 allele for AD were 3.4 (1.7-7.0) for one epsilon 4 allele and 20.3 (2.5-166.6) for two epsilon 4 alleles in early-onset type, and 6.7 (3.9-11.3) for one epsilon 4 allele and 19.0 (2.5-145.6) for two epsilon 4 alleles in late-onset type. These ratios were significantly increased in both early-onset AD and late onset AD. Kaplan-Meier survival analysis, which estimates the age of onset for subjects with no, one, and two epsilon 4 alleles in early-onset and late-onset type, revealed a significant dose effect where each additional epsilon 4 allele made the age of onset earlier (p < 0.0001). The age of onset is 9.7 years earlier for two epsilon 4 bearers and 3.9 years earlier for one epsilon 4 bearers than no epsilon 4 bearers in late-onset AD, 2.9 years earlier for two epsilon 4 bearers and 1.4 years earlier for one epsilon 4 bearers than no epsilon 4 bearers in early-onset AD. Moreover, we studied an association between apoE epsilon 2 allele and early-onset AD and late-onset AD. There was a significantly decreased frequency of apoE epsilon 2 allele in patients with late-onset AD (p = 0.026), although the frequency of apoE epsilon 2 was not changed significantly in early onset AD (p = 0.360). The odds ratios referred to no epsilon 2 allele for AD were 1.9 (0.6-5.7) for one epsilon 2 allele in early-onset type, and 0.4 (0.2-0.9) for one epsilon 2 allele in late-onset type. Our study suggested the difference in the effect of apoE genotype on developing AD between early-onset and late-onset type in Japanese patients. PMID- 9369085 TI - Medicare rerun. Congress tinkers with but does not fix Medicare solvency. PMID- 9369087 TI - A drop in the right direction. PMID- 9369086 TI - Drug wars. PMID- 9369089 TI - KCME-TV. PMID- 9369088 TI - Pap smear concerns. PMID- 9369090 TI - Communication with the elderly psychiatric outpatient. AB - Elderly psychiatric patients pose special challenges to effective communication. Psychiatric diagnosis relies heavily on verbal communication and can become a casualty in this process. Consequences of an incomplete or distorted data base include inappropriate treatment and polypharmacy. The authors examine the causes of doctor-patient miscommunication and, propose specific, simple measures to improve information exchange for both initial evaluation and follow-up of the geropsychiatric patient. PMID- 9369091 TI - Women's advancement in medicine and academia: barriers and future perspectives. AB - Although women made early advancements in the field of medicine during the second half of the 19th century, they were not able to make relevant strides in both medicine and academia until the 1960s. Despite women's recent advancements, obstacles and barriers to their hope of achieving fairness and equality in their professional and academic careers still exist. These practices include professional discrimination, blatant sexism, lack of appropriate mentors, and unfair faculty promotion processes. In this article, we address the most common problems affecting women physicians' advancement in academic medicine. We also focus on the role of mentorship as a relevant and beneficial factor for progress in their medical and academic careers. Finally, we provide a perspective designed to resolve most of the barriers confronting women physicians in their quest for advancement in academic medicine. PMID- 9369092 TI - Artemisinin: an endoperoxidic antimalarial from Artemisia annua L. PMID- 9369093 TI - Marine glycolipids. PMID- 9369095 TI - Before crossing over: the advantages of eukaryotic sex in genomes lacking chiasmatic recombination. AB - Non-recombining populations should suffer from four classic population genetic disadvantages: (1) they cannot reverse Muller's Ratchet, the accumulation of deleterious mutations caused by genetic drift and mutation; (2) whenever the fix a favourable mutation they lose all unlinked favourable variants; (3) they tend to lose favourable mutations that are linked to deleterious mutations; and (4) their genetic loads can be quite high when deleterious mutations have synergistic effects. It is commonly assumed that inter-chromosomal recombination (independent assortment) can counter these phenomena, but this has been studied only for the genetic load case. In contrast, many studies have shown that recombination via crossing over can counter these phenomena. Here we first show that segregation alone can strongly decelerate Muller's Ratchet in diploids, i.e. that recombination is not the only way to do so. We then show that inter-chromosomal recombination can indeed deal with phenomena (1) to (3) above very effectively if the genome consists of a moderate number of chromosomes. Therefore, if the above advantages of genetic recombination played a large role in the initial success of eukaryotic sex, the crucial moment in the origin of sex might have been the evolution of inter-chromosomal recombination, i.e. the evolution of genome segmentation, segregation, and syngamy. Crossing over might have become established as a major recombinational device only later, eliminating the disadvantages of extensively segmented genomes. PMID- 9369096 TI - The effects of spontaneous mutation on quantitative traits. II. Dominance of mutations with effects on life-history traits. AB - We studied the dominance of the effects of chromosomes carrying unselected mutations on five life-history traits in Drosophila melanogaster. Mutations were accumulated on the second chromosome for 44 generations in the absence of natural selection. Traits studied were female fecundity early and late in adult life, male mating ability, and male and female longevity. Homozygous effects were estimated for 50 mutant lines, and heterozygous effects were estimated by crossing these lines in a partial diallel scheme. Direct estimates of dominance showed that the effects of mutants are at least partially recessive. Heterozygotes had higher trait means than homozygotes in all five cases, and these differences were significant for late fecundity and female longevity. For all traits, genetic variance was larger among homozygous crosses than among heterozygous crosses. These results are consistent with those of many other studies that suggest that both unselected mutations and those found segregating in natural populations are partially recessive. PMID- 9369097 TI - Environmental effects on body size variation in Drosophila melanogaster and its cellular basis. AB - Eight isofemale lines of Drosophila melanogaster were raised at four temperatures and at four yeast concentrations in their food. Temperature and food show a significant interaction in determining wing length and thorax length, affecting mean size per line and genetic variation between lines. The combination of low temperature and poor food conditions leads to a sharp increase in the genetic variation over lines of both body size characters. The increase in genetic variation in wing length under less favourable conditions is due to an increase in genetic variation of both cell size and cell number. Changes in wing area in response to both temperature and food level follow a common cell size/cell number trajectory. Changes in wing size are obtained by line-specific changes in the cellular composition of the wing, rather than by changes specific for the environmental factor. PMID- 9369098 TI - Rapid fixation of deleterious alleles can be caused by Muller's ratchet. AB - Theoretical arguments are presented which suggest that each advance of Muller's ratchet in a haploid asexual population causes the fixation of a deleterious mutation at a single locus. A similar process operates in a diploid, fully asexual population under a wide range of parameter values, with respect to fixation within one of the two haploid genomes. Fixations of deleterious mutations in asexual species can thus be greatly accelerated in comparison with a freely recombining genome, if the ratchet is operating. In a diploid with segregation of a single chromosome, but no crossing over within the chromosome, the advance of the ratchet can be decoupled from fixation if mutations are sufficiently close to recessivity. A new analytical approximation for the rate of advance of the ratchet is proposed. Simulation results are presented that validate the assertions about fixation. The simulations show that none of the analytical approximations for the rate of advance of the ratchet are satisfactory when population size is large. The relevance of these results for evolutionary processes such as Y chromosome degeneration is discussed. PMID- 9369099 TI - P element excision in Drosophila is stimulated by gamma-irradiation in transient embryonic assays. AB - The influence of gamma-irradiation on P element excision and excision-site repair mechanisms was directly tested by embryonic somatic excision assays. Preblastoderm P[ry+, delta 2-3](99B) embryos, having a stable source of somatically active P transposase, were irradiated previous to injection with P excision indicator plasmids. Frequencies of precise or nearly precise P excision increased with gamma-ray doses ranging from 0.5 to 3.5 Gy. Higher doses resulted in frequencies close to that in unirradiated embryos, though considerable embryonic lethality was also evident at these doses. A direct positive interaction between gamma-irradiation and P element activity is concluded. PMID- 9369100 TI - Practice parameters for the treatment of mucosal ulcerative colitis--supporting documentation. The Standards Practice Task Force. The American Society of Colon and Rectal Surgeons. PMID- 9369101 TI - Perianal Bowen's disease: a clinicopathologic study of 47 patients. AB - PURPOSE: Perianal Bowen's disease is an uncommon squamous-cell carcinoma in situ usually treated by surgical excision. There are controversies concerning surgical margin extent, because the disease is likely to recur in nonexcised skin areas of the anal and perianal skin. The aims of this study were 1) to determine the recurrence rate after different surgical treatments and 2) to determine if molecular markers might have a prognostic role in perianal Bowen's disease. METHOD: Retrospective chart review from 1972 to 1993 of 47 patients with perianal Bowen's disease was undertaken. Follow-up was obtained by office visits and/or phone questionnaire. Immunohistochemical analysis for p53 protein and Ki-67 nuclear antigen was conducted on fixed tissue specimens. RESULTS: Twenty-six patients were treated by wide local excision with microscopic clearance of resection margins, 15 by local excision with only macroscopic clearance of resection margins, 5 by CO2 laser vaporization, and 1 by abdominoperineal resection because of fecal incontinence. Median follow-up for the entire population was 104 (range, 16-273) months. The incidence of local recurrence was 23.1 percent (6/26) after wide local excision, 53.3 percent (8/15) after local excision, and 80 percent (4/5) after CO2-laser vaporization. Recurrence rate estimated by Kaplan-Meier analysis is statistically different (P = 0.002) between radically treated patients (wide local excision/abdominoperineal resection; n = 27) and patients undergoing conservative treatment (local excision/laser vaporization; n = 20). Among patients with recurrence, the median time until recurrence was 38.5 (range, 3-89) months and 41.5 (range, 4-111) months after conservative and radical treatment, respectively. Nine of 20 (45 percent) patients in the conservative group and none of the 27 patients in the radical group had multiple episodes of recurrence (P < 0.001). In addition, 3 of 20 and 0 of 27 patients in the respective groups developed an invasive cancer (P = 0.034). Positive staining for p53 protein was observed in 12 (33.3 percent) of the 36 tissue specimens available for immunohistochemical analysis. Recurrence occurred in 9 of 24 (37.5 percent) patients negative for p53 and in 6 of 12 (50 percent) patients with positive p53 expression (P = not significant). Ki-67 antigen-graded expression from 1+ to 4+ did not reveal any correlation with incidence of recurrence. Recurrence rate did not differ by p53 and Ki-67 results, either in the overall group of 36 patients or stratified by surgical treatment groups. CONCLUSION: Wide local excision for perianal Bowen's disease leads to a significantly lower recurrence rate than local excision or laser therapy. Follow up longer than five years is recommended because of the risk of late recurrence. p53 protein and Ki-67 antigen immunohistologic expression may not have a prognostic role in perianal Bowen's disease. PMID- 9369102 TI - Incidence of free colorectal cancer cells on the peritoneal surface. AB - BACKGROUND: The etiology and significance of port site recurrence occurring after laparoscopic-assisted resection for colorectal cancers will not be determined until controlled clinical trials determine if it is a predictor of outcome. Indirect evidence in support of transcoelomic spread of viable cancer cells to port sites during resection can be postulated by the presence of free cells on the fresh surface of colorectal specimens during primary resection. PURPOSE: The study contained herein was undertaken to determine the incidence of free surface colorectal cancer cells by cytology during elective open resection and to correlate their presence with clinicopathologic variables. METHODS: Fresh clamped and ligated consecutive colorectal cancer specimens were assessed in the operating room during primary resection for the presence of free colorectal cancer cells during an 18 month period at one institution. Clinicopathologic variables were assessed prospectively and blinded to cytology results. Interobserver reliability of cytologists was excellent (unweighted kappa, 0.93). RESULTS: Overall, 15 of 103 (14.6 percent) colorectal cancers had positive cytology for cancer cells on the peritoneal or perirectal surface of the bowel. T3 and T4 tumors, the size or site of the tumor, lymph node status, mucinous characteristic, degree of differentiation, and the presence of vascular or neural invasion did not reach statistical significance as predictors of positive cytology in this study sample. The operative procedure performed was a statistically significant predictor of positive cytology. More than 50 percent of lymph nodes involved (28 percent), poorly differentiated tumors (28 percent), and the presence of liver metastases (22 percent) demonstrated a higher incidence of positive cytology, but this did not reach significant levels because of the limited power of the study sample for subgroup analysis. DISCUSSION: The presence of free surface colorectal cancer cells gives only indirect support to the transcoelomic route to port site recurrence. The significance and true incidence will only be determined by prospective database analysis and randomized, controlled trials. PMID- 9369103 TI - Simultaneous bilateral oophorectomy does not improve prognosis of postmenopausal women undergoing colorectal resection for cancer. AB - PURPOSE: Synchronous or metachronous ovarian metastases are common along the natural course of colorectal carcinoma. We attempted to prospectively assess the prognostic impact of simultaneous bilateral oophorectomy in postmenopausal women undergoing curative resection for colorectal cancer. METHODS: Between 1980 and 1990, simultaneous bilateral oophorectomy was proposed in each postmenopausal woman referred to our institution for treatment of colorectal cancer. A subset of 92 patients underwent a curative resection. Therefore, two groups were designed for comparison of the procedure. Group I included 41 patients who accepted surgical castration, and Group II consisted of the 51 remaining patients who refused. Prospective analysis of all patients was performed. Results were assessed with a follow-up of 60 months after surgery, with 97.9 percent completion. Local recurrence and liver metastases rates were compared by the chi squared test. Survival in each group was calculated by the Kaplan-Meier method and compared by the log-rank test. RESULTS: One patient (1/41; 2.4 percent) had ovarian metastases detected on the operative specimen. Local recurrence or liver metastases rates were not affected by oophorectomy (P = 0.73; P = 0.25). Five year actuarial survival rates were not significantly different whether patients had oophorectomy (81.6 percent) or not (87.9 percent; P = 0.62). CONCLUSIONS: Our results suggest that microscopic synchronous ovarian metastasis is rare at the time of curative resection of a colorectal carcinoma in postmenopausal women. Because simultaneous bilateral oophorectomy does not modify prognosis, this procedure seems to be unwarranted. PMID- 9369104 TI - Synergistic effects of hyperthermia in preoperative radiochemotherapy for rectal carcinoma. AB - PURPOSE: We investigated the effectiveness of hyperthermia added to preoperative radiation and chemotherapy for the treatment of rectal carcinoma. METHODS: Forty one patients receiving preoperative radiation were divided into two groups, Group A (20 patients; receiving radiation, hyperthermia, and chemotherapy) and Group B (21 patients, receiving no hyperthermia). Total dose of radiation was 40.5 Gy. Hyperthermia was administered using 8 MHz of radiofrequency. Rectal temperature reached 42 degrees C. A total dose of 3,400 mg of 5-fluorouracil given by suppository was used as the chemotherapeutic agent. Effect of the preoperative treatment was assessed by tumor reduction on barium enema, histologic findings of the resected specimens, area measurement of the residual cancer tissue, and by silver-staining nucleolar organizer region (AgNOR) score. RESULTS: Tumor reduction on barium enema was significantly greater in Group A than in Group B (P < 0.01). Excluding two cases of mucinous carcinoma because a large acellular mucinous accumulation added materially to the cancerous area, the ratio of residual cancer area to total lesion size in Group A was significantly smaller than in Group B (P < 0.05). AgNOR score of the resected tumor tended to be smaller in Group A than in Group B. CONCLUSION: Addition of hyperthermia resulted in a greater degree of tumor necrosis and was considered to be useful as a preoperative treatment for rectal carcinoma. PMID- 9369105 TI - Hartmann's procedure vs. abdominoperineal resection for palliation of advanced low rectal cancer. AB - In managing advanced low rectal adenocarcinomas in medically fit patients, surgical resection offers the best palliation. Tenesmus, bleeding per rectum, sacral pain, and sciatic pain are common complaints, which are not relieved by radiotherapy or fulguration. The most appropriate resection, however, remains controversial. Abdominoperineal resection is faster and simpler to perform but leaves behind a perineal wound with associated complications. Hartmann's procedure requires adequate mobilization below the tumor and may be technically more demanding but avoids a perineal wound. Therefore, an analysis of outcome in patients treated by Hartmann's procedure vs. abdominoperineal resection was made. METHOD: Fifty-four symptomatic patients with advanced rectal adenocarcinoma arising within a median of 5 (range, 4-8) cm from the anal verge treated between June 1989 and October 1995 were studied. Twenty-eight patients (17 males; mean age, 67.6 +/- 10.3 years) had Hartmann's procedure, and 26 patients (12 females; mean age, 68.8 +/- 8.3 years) were treated by abdominoperineal resection. Mean follow-up was 23.5 months (+/-17.5) and 18.6 months (+/-12.9) in Hartmann's procedure and abdominoperineal groups, respectively. RESULTS: Mean operative time was 138.4 +/- 26.7 minutes for Hartmann's procedure group and 124.6 +/- 27.1 minutes for the abdominoperineal resection group (P > 0.05; not significant). Postoperatively, Hartmann's procedure group started oral intake at a mean of 2.3 days, and stomas were functioning at a mean of 3.1 days compared with 2.6 days for oral intake and 3 days for stoma functioning in the abdominoperineal resection group. Hartmann's procedure group was ambulant after a mean of 2.4 days vs. a mean of 3.2 days in the abdominoperineal resection group. Postoperative abdominal wound infection occurred in 18 and 19 percent, respectively, in Hartmann's procedure and abdominoperineal resection groups. Forty-six percent of patients had perineal wound sepsis, and 38 percent had perineal wound pain in the abdominoperineal resection group. These complications were absent in Hartmann's procedure group. Postoperative stay was similar in both groups. CONCLUSION: We conclude that Hartmann's procedure offers superior palliation compared with abdominoperineal resection because it provides good symptomatic control without any perineal wound complications and pain. PMID- 9369106 TI - Glyceryl trinitrate vs. sphincterotomy for treatment of chronic fissure-in-ano: a randomized, controlled trial. AB - PURPOSE: This study was undertaken to compare local application of a glyceryl trinitrate ointment with lateral internal sphincterotomy for the treatment of chronic fissure-in-ano. PATIENTS AND METHODS: A sample of 24 consecutive patients with chronic anal fissure was randomly allocated to treatment with sphincterotomy or local glyceryl trinitrate. Patients were followed-up for a median of 22 months. RESULTS: All 12 patients healed following sphincterotomy; 10 of 12 healed with local glyceryl trinitrate (P = 0.239). There were no recurrences or side effects in either group. CONCLUSIONS: Local application of glyceryl trinitrate can avoid surgery in more than 80 percent of patients with chronic anal fissure. PMID- 9369107 TI - Muscle transformation of the sartorius muscle in a canine model: clinical impact for electrodynamic graciloplasty as a "neosphincter". AB - PURPOSE: Transformation of fast-twitching skeletal muscles to slow-twitching, slowly fatigable muscles has become of clinical interest in the recent past. Transposition and transformation of the gracilis muscle to use it as a substitute for a resected or defected anal sphincter (graciloplasty) have been reported as achieving promising results in the treatment of fecal incontinence caused by sphincter defects or following abdominoperineal anorectal excision for cancer. METHOD: This experimental study used a canine model and the sartorius muscle to evaluate the functional efficiency of two different configurations of the muscle loop to compare the presently applied transformation program (8 weeks) with a shorter (5 weeks) protocol. In six beagle dogs, both sartorius muscles were wrapped around two stomas, either in an alpha fashion or in the so-called split sling technique. Muscle transformation was achieved by controlled neuromuscular stimulation either during eight (Program A) or five weeks (Program B). After completion of the transformation period, the function of the muscle slings was evaluated by manometry, and histomorphologic evaluation of the sartorius muscles was performed. RESULTS: It was shown that muscle transformation led to a slowly fatigable muscle that made it possible to perform continuos (tetanic) contraction, regardless of the configuration or the duration of the transformation. Median pressures created by these muscles also did not differ significantly. In accordance with these functional findings, the histologic evaluation showed the typical, significant increase of Type I fibers in both muscle slings and following both transformation protocols. Although the decrease of fast-twitching Type II fibers was more pronounced following the conventional (8 weeks) program, this finding did not influence the functional results. CONCLUSIONS: Results of our experiment indicate the possibility for using a shorter transformation protocol for transformation of the gracilis muscle during graciloplasty in the clinical setting. Furthermore, the efficacy and safety of the modified (split-sling) wrap technique was demonstrated. PMID- 9369108 TI - Anorectal function in systemic sclerosis: correlation with esophageal dysfunction? AB - PURPOSE: This study was designed to compare esophageal and anorectal function parameters in patients with systemic sclerosis and to define the role of anorectal manometry in the diagnosis of gastrointestinal involvement of systemic sclerosis. PATIENTS AND METHODS: Twenty-six consecutive patients (22 females) with systemic sclerosis originally referred for assessment of esophageal function were evaluated by esophageal and anorectal manometry. Anorectal function parameters were compared between patients with normal and those with disturbed esophageal function. RESULTS: A total of 17 of 26 patients (65 percent) had severe esophageal dysfunction with aperistalsis of the lower two-thirds of the esophagus, whereas 9 patients (35 percent) had normal esophageal manometry. Only three patients (11.5 percent) suffered from occasional fecal incontinence. Anorectal function parameters (resting pressure, maximum squeeze pressure, perception threshold) were not significantly different between patients with normal and those with disturbed esophageal motility. Rectoanal inhibitory reflex was excitable in nearly 90 percent of patients. CONCLUSION: In an unselected group of patients with systemic sclerosis, fecal incontinence and abnormal anorectal function are rather rare findings. Anorectal manometry cannot differentiate between patients with and without gastrointestinal involvement of systemic sclerosis. PMID- 9369109 TI - Complications of absorbable pelvic mesh slings following surgery for rectal carcinoma. AB - PURPOSE: To evaluate the intraoperative, postoperative, and long-term complications of an absorbable pelvic mesh sling after surgery for rectal carcinoma. METHODS: A retrospective review of medical records from April 8, 1991, through April 8, 1996. RESULTS: Twenty patients with a mean age of 57 (range, 37 79) years underwent pelvic mesh sling placement. The tumor stages were as follows: Stage I, 5; Stage II, 2; Stage III, 11; and Stage IV, 1. A recurrent perianal basal cell carcinoma was not included in the staging group. Surgery consisted of 18 abdominoperineal resections, 1 total proctocolectomy, and one Hartmann's procedure. Mean follow-up was 18 (range, 2-49) months. There were no intraoperative complications related to mesh placement. Twenty-nine complications occurred in 14 patients during the immediate postoperative period. Five were possibly mesh-related and included a pelvic abscess, perineal seroma, toxic perineal wound, pulmonary embolus, and lower extremity deep venous thrombosis, respectively. A mild postoperative ileus developed in 17 patients (85 percent), and a diet was initiated at a mean of seven (range, 4-24) days. Fourteen patients received postoperative radiotherapy with a mean dose of 5,339 (range, 2,500 7,020) cGy delivered in 180-cGy fractions. There were 14 immediate complications caused by radiotherapy in 11 patients, but only two patients required delays in treatment. Two patients had diarrhea alone, six developed perineal dermatitis alone, and three patients had both diarrhea and perineal dermatitis. All patients with diarrhea had received chemoradiation. One patient developed a partial small bowel obstruction following radiation. CONCLUSIONS: Absorbable pelvic mesh sling placement can be performed with minimum morbidity and is recommended following surgery for rectal cancer when radiation is anticipated as part of multimodality therapy. PMID- 9369110 TI - Changes in bowel function after hysterectomy. AB - PURPOSE: It has been suggested that hysterectomy has a disturbing influence on bowel function. To assess the incidence and nature of these changes, we performed a retrospective study. METHODS: A retrospective study was performed in all 593 women who had undergone hysterectomy between 1989 and 1993. A control group consisted of 100 women who had undergone laparoscopic cholecystectomy. RESULTS: The response rate was 90 percent (n = 531; median age, 45 (range, 18-84) years). Of the responding women, 315 patients (59 percent) indicated a normal defecation pattern before hysterectomy. Of these women, severe deterioration in bowel function was reported by 98 patients (31 percent), whereas 36 women (11 percent) mentioned a moderate change after hysterectomy. Most frequent symptoms were severe straining (90 patients), incomplete and/or digital evacuation (83 and 50 patients, respectively). According to most patients, the changes in bowel function were reported to have started within one month after hysterectomy. With advancing age, fewer complaints were recorded (P = 0.008). No significant difference was found in the incidence of disturbed bowel function between the different types of operation (abdominal, vaginal, supravaginal, or radical hysterectomy). In the control group, the response rate was 96 percent. Median age of these women was 46 (range, 25-78) years. Fifty-eight patients (60 percent) reported normal bowel function before laparoscopic cholecystectomy. In this group of patients, disturbed bowel function after surgery was reported by five women (9 percent), which figure is significantly (P < 0.001) lower compared with that in the corresponding hysterectomy group. CONCLUSION: Hysterectomy seems to play an important role in the pathogenesis of disturbed defecation. PMID- 9369112 TI - Early resolution of Ogilvie's syndrome with intravenous neostigmine: a simple, effective treatment. AB - PURPOSE: Our aim was to assess the value of a parasympathomimetic drug (neostigmine) in the early resolution of acute colonic pseudo-obstruction (Ogilvie's syndrome). METHODS: A prospective study was undertaken in 18 consecutive patients (mean age, 76 (range, 31-87) years) with acute colonic pseudo-obstruction. After a varying period of conservative treatment in all cases, 16 patients with persistent, massive abdominal distention were given intravenous neostigmine. RESULTS: A rapid and satisfactory clinical and radiologic decompression of the large bowel was obtained in 12 patients (75 percent) after a single dose of the drug; another patient had complete resolution after a second dose, and the other 3 patients had only partial resolution, in one of them after a second dose of the drug. No patient required surgical decompression of the bowel. CONCLUSION: These results give support to the theory of excessive parasympathetic suppression in most cases of Ogilvie's syndrome. The treatment with intravenous neostigmine has proved very effective, preventing in many cases prolonged periods of uncomfortable and potentially hazardous conventional conservative management and avoiding surgical treatment in a consecutive series of patients. PMID- 9369111 TI - Improvements in mechanical bowel preparation for elective colorectal surgery. AB - PURPOSE: This study was undertaken to determine whether a mechanical bowel preparation with 2 liters of polyethylene glycol solution combined with a laxative (Group A) increases the acceptability of bowel preparation and reduces discomfort compared with 4 liters of polyethylene glycol solution (Group B). METHODS: One hundred patients undergoing an elective colorectal resection were included in a prospective, randomized study. Acceptability (nausea, vomiting, abdominal cramps, discomfort from insertion of the nasogastric tube, and anal discomfort) was assessed using visual analog scales. Efficacy of bowel lavage was scored intraoperatively by a blinded surgeon. RESULTS: Overall acceptability was 5.1 +/- 2.8 in Group A patients and 5.6 +/- 2.6 in Group B patients (P = 0.5). The incidence and visual analog score for nausea, vomiting, anal discomfort, and cramps were not different between groups. Excellent efficacy of bowel preparation was shown in 94 percent of patients in Group A and 84 percent of patients in Group B (P = 0.5). The incidence of septic complications was 2 percent in Group A patients and 12 percent in Group B patients (P = 0.06). CONCLUSION: Because the acceptability of both cleansing regimens were not different, 2 liters of polyethylene glycol plus Prepacol should be preferred because the amount of fluid administered to clean the bowel is reduced and the nasogastric tube can always be avoided. PMID- 9369113 TI - Antimesenteric perforations of the colon during diverticular disease: possible pathogenetic role of ischemia. AB - The pathogenesis of free perforations occurring on the antimesenteric border of the pelvic colon during the course of diverticular disease has received little attention, with most being generically referred to as diverticular perforations. PURPOSE: This study was designed to identify the pathogenetic factors responsible for free perforations that may occur in the antimesenteric intertenial area during the course of diverticular disease. METHODS: Vascular alterations of the colonic wall associated with diverticula and open antimesenteric perforations were analyzed. RESULTS: Previous data on the site of diverticula formation and related intramural vascular alterations were confirmed. A subserosal vascular network developed in the antimesenteric intertenial area in instances of multiple bilateral diverticula. Free perforations occurred in the antimesenteric haustral area only with multiple bilateral diverticula. CONCLUSIONS: Alterations of the intramural vascular pattern secondary to the presence of multiple and bilateral diverticula may predispose the colonic wall to acute vascular injury. These changes may be enhanced by an episodic increase of intraluminal pressure and consequent distention of the colonic wall occurring in the course of diverticular disease. PMID- 9369114 TI - Fulminant amebic colitis: analysis of 55 cases. AB - Fulminant amebic colitis is a rare disease with high morbidity and mortality. PURPOSE: This study was designed to identify the most frequent clinical and histopathologic features of fulminant amebic colitis and to analyze results of surgical treatment and the existence of risk factors for mortality. MATERIALS AND METHODS: A retrospective analysis was conducted of clinical and histopathologic data of 55 patients with fulminant amebic colitis. Data were obtained from the files of autopsies and surgical operations that had been performed at a referral center in Mexico from 1943 through 1994. RESULTS: Median age was 52 (range, 18 79) years. There were 34 men (62 percent) and 21 women (38 percent). Diabetes mellitus and chronic alcoholism were the most frequent diseases in association with fulminant amebic colitis (40 and 31 percent, respectively). The most frequent clinical manifestations were abdominal pain, diarrhea, rectal bleeding, and fever. There was a coexistent amebic liver abscess in 54 percent of patients. The main histopathologic characteristics were necrosis, presence of trophozoites, and acute and/or chronic inflammation. Of 25 patients who underwent surgery, only six survived (operative mortality, 76 percent; overall mortality, 89 percent). The variables that correlated with mortality were longer duration of symptoms, lower count of leukocytes, nonsurgical treatment, nonresective surgical procedure, hospital admission before 1971, and invasion of trophozoites into or through the muscularis. CONCLUSIONS: The results may help to obtain an earlier diagnosis and establish proper treatment of fulminant amebic colitis. PMID- 9369116 TI - Inhibitory effect of calcium on carcinogenesis at the site of colonic anastomosis: an experimental study. AB - PURPOSE: A study was made to assess the effect of oral calcium supplementation on colorectal carcinogenesis at the colocolic suture line and in the rest of the colon following administration of a carcinogen. METHODS: Fifty-nine rats were randomly divided into two groups: control (given a standard diet for rats and mice containing 0.8 percent calcium) and treatment (given the same diet as before but with 2 percent calcium). Carcinogenesis was induced by 26 weekly injections of 1,2-dimethylhydrazine. All animals were subjected to an end-to-end colonic anastomosis at the beginning of the experiment using five stitches of steel wire. RESULTS: The control group developed significantly more tumors per animal at both the anastomosis (P < 0.001) and in the rest of the colon (P < 0.001). In addition, the percentage of rats with tumors was significantly higher in the control group at both the anastomosis (chi-squared = 12; df = 1, P < 0.001) and in the rest of the colon (chi-squared = 7.12; df = 1, P < 0.01). The mean surface of tumors was likewise greater in the control group at the anastomosis (P < 0.001) and throughout the rest of the colon (P < 0.001). Finally, there were significantly more small-bowel tumors (excluding the duodenum) in the control group (P < 0.05). CONCLUSIONS: It is concluded that calcium supplementation decreases the tumor yield at the site of end-to-end colonic anastomosis and in the rest of the colon and small bowel (excluding the duodenum). PMID- 9369115 TI - Butyrate inhibits deoxycholate-induced increase in colonic mucosal DNA and protein synthesis in vivo. AB - PURPOSE: Crypt surface hyperproliferation is an intermediate biomarker of colon cancer risk. In vitro studies indicate that the short-chain fatty acid and antineoplastic agent butyrate may reverse the crypt surface hyperproliferation induced by the secondary bile acid and tumor promoter, deoxycholate. We hypothesized that butyrate may reverse deoxycholate-induced crypt surface proliferation in vivo. METHODS: Thirty-one Sprague-Dawley rats (250-300 g) underwent surgical isolation of the colon and 24-hour luminal instillation of either sodium chloride, butyrate, deoxycholate, or butyrate plus deoxycholate (all solutions, 2 ml; pH 7; total sodium = 20 mM). Study variables included colon weight, mucosal DNA, mucosal protein, and proliferating cell nuclear antigen immunohistochemistry, labeling of which was determined in five crypt compartments from base to surface (12 crypts per rat). Labeling indexes were calculated as proliferating cell nuclear antigen immunohistochemistry-labeled cells divided by total counted cells in the whole colonic crypt and each of five crypt compartments. The phi(h) value (an index of premalignant risk) was calculated as the ratio of labeled cells in the two surface compartments divided by the total labeled cells. RESULTS: Deoxycholate significantly increased colon wet weight, mucosal protein, total crypt labeling indexes, crypt surface labeling indexes, and the phi(h) value and raised the mucosal DNA content. Butyrate alone slightly reduced total mucosal DNA and protein content. The combination of butyrate plus deoxycholate significantly decreased mucosal DNA and tended to reduce mucosal protein compared with deoxycholate alone. In contrast to prior in vitro findings, butyrate plus deoxycholate did not reverse the deoxycholate-induced surface hyperproliferative changes as measured by proliferating cell nuclear antigen labeling. CONCLUSIONS: Because co-treatment with butyrate plus deoxycholate inhibits deoxycholate-induced increases in total mucosal DNA and protein content, we conclude that butyrate may play a role in maintaining the proliferative balance of the colonic mucosa, in vivo. However, co-treatment with butyrate plus deoxycholate does not reverse the deoxycholate-induced increases in colon weight and proliferating cell nuclear antigen labeling indexes under the studied experimental conditions. PMID- 9369117 TI - Rectal prolapse associated with bulimia nervosa: report of seven cases. AB - PURPOSE: Rectal prolapse is a condition in which, when complete, the full thickness of the rectal wall protrudes through the anus. Bulimia nervosa is an eating disorder characterized by periodic food binges, which are followed by purging. Purging usually takes the form of self-induced vomiting, laxative abuse, and/or diuretic abuse. We report seven cases of rectal prolapse associated with bulimia nervosa. METHODS: The case histories of seven women with rectal prolapse and bulimia nervosa, average age 29 (range 21-42) years, seen over a period of 11 years (1987-1997) were reviewed. An analysis of the clinical data, including history, presenting physical examination, surgical treatment, and outcome was performed. RESULTS: All seven patients had a diagnosis of bulimia nervosa, made either before or with a diagnosis of rectal prolapse. Rectal prolapse was confirmed in each patient at anorectal examination. Five patients underwent sigmoid resection with proctopexy, one died before operative therapy, and one awaits further treatment. One of the five surgical patients had a recurrence that was managed by a perineal rectosigmoidectomy. CONCLUSION: To our knowledge, despite extensive review of both bulimia nervosa and rectal prolapse as seen in the medical literature, an association between the two has not been described previously. Several aspects of bulimia nervosa, including constipation, laxative use, overzealous exercise, and increased intra-abdominal pressure from forced vomiting are likely causes for the probable relationship with rectal prolapse. The possibility that an atypically young female presenting with rectal prolapse may also have bulimia nervosa should be taken into account by clinicians. This may assist the diagnosis of bulimia nervosa, a disease with multiple morbidities. Conversely, a patient being treated for bulimia nervosa who develops anorectal symptoms may come to earlier diagnosis and treatment for rectal prolapse. PMID- 9369118 TI - Toxic shock syndrome and necrotizing fasciitis complicating neglected sacrococcygeal pilonidal sinus disease: report of a case. AB - PURPOSE: This study was conducted to report the rare combination of necrotizing fasciitis and toxic shock syndrome, which both complicated neglected sacrococcygeal pilonidal sinus disease. METHODS: A case report is presented. RESULTS: We describe the rare case of a previously healthy adult male patient who developed necrotizing fasciitis and toxic shock syndrome associated with Streptococcus pyogenes and Bacteroides fragilis. Patient's response to emergency surgery followed by repeated debridements of necrotic tissue, together with aggressive fluid resuscitation, broad-spectrum antibiotic coverage, and hyperbaric oxygenation was good. CONCLUSION: This case serves again as a clear reminder that neglected pilonidal sinus disease can lead to unusual and life threatening consequences. PMID- 9369119 TI - Expandable metal stent application in obstructing carcinoma of the proximal colon: report of a case. AB - PURPOSE: The increased mortality of emergency vs. elective colonic surgery applies equally to the right and left colon. Recent interest has surrounded the application of expandable metal stenting in acute obstruction but has been confined to the left colon. We describe successful application of stenting in the right colon, allowing postponement of a particularly high-risk laparotomy. METHODS: A patient with acute bilateral iliofemoral thromboses simultaneously developed complete obstruction of the proximal transverse colon. After heparinization and under fluoroscopic control, a 10-cm-long, self-expanding Wall stent (Schneider, Bulach, Switzerland), 22 mm in diameter, was manipulated across the obstruction. RESULTS: Immediate decompression with symptomatic relief ensued. The stent prevented obstruction during a 10-week period of anticoagulation, and repeat duplex scanning showed resolution of iliac thrombus. An elective right hemicolectomy was then performed. Postoperative course was uncomplicated, and histopathology confirmed a Dukes B carcinoma. CONCLUSIONS: This case, in which a potentially hazardous laparotomy was delayed until the operative risk improved, defines a new role for stenting in colonic obstruction and demonstrates an extension of its applicability to the right colon. Literature review found no other report of stent application in the right colon. PMID- 9369120 TI - Atraumatic and expeditious laparoscopic bowel handling using a new endoscopic device. AB - In laparoscopic colorectal surgery, effective handling of the bowel is mandatory to avoid bowel injury and excessive manipulation and to obtain adequate traction and clear exposure. We have developed a simple laparoscopic tool that permits effective and safe retraction of the small or large intestine and that is especially helpful in taking down the hepatic and splenic flexures and in dissecting the mesorectum. PMID- 9369121 TI - Oral Fleet Phospho-Soda: doses and interval between them. PMID- 9369122 TI - Ileal intubation at colonoscopy. PMID- 9369123 TI - Philip Rubin. PMID- 9369124 TI - Tumor cell heterogeneity: impact on mechanisms of therapeutic drug resistance. AB - PURPOSE: The aim of these studies was to determine whether chemotherapy-resistant tumor cell sublines derived from a single starting cell population with identical treatment protocols, have the same mechanism of resistance. METHODS AND MATERIALS: Twelve cyclophosphamide-resistant sublines were derived from KHT-iv murine sarcoma cells by repeated exposures to 2, 4, or 8 microg/ml doses of 4 hydroperoxycyclophosphamide (4-OOHCP). To investigate possible mechanisms of resistance, glutathione (GSH) levels, glutathione S-transferase (GST) activity, and aldehyde dehydrogenase (ALDH) activity were determined. In addition, studies with the GSH depletor buthionine sulfoximine (BSO) and the ALDH inhibitor diethylamino-benzaldehyde (DEAB) were undertaken. RESULTS: Resistant factors to 4 OOHCP, assessed at 10% clonogenic cell survival, ranged from 1.5-7.0 for the various cell lines. Crossresistance to melphalan and adriamycin also were commonly observed. Increased GSH levels, GST activity and ALDH activity were detected in the sublines but not all exhibited the same pattern of biochemical alterations. The response to GSH and ALDH inhibitors also varied among the sublines; the resistance being reversible in some cell lines but not others. CONCLUSION: The present results indicate that when resistant sublines are derived simultaneously from the same starting cell population, the observed mechanisms of resistance may not be the same in each of the variants. These findings support the hypothesis that preexisting cellular heterogeneity may affect mechanisms of acquired resistance. PMID- 9369125 TI - Steepness of the dose-response curve as a function of volume in an experimental tumor irradiated under ambient or hypoxic conditions. AB - PURPOSE: Radiation dose-response curves play a fundamental role in the attempts to optimize radiotherapy, and it is a major task in clinical and experimental radiation research to characterize and quantify the factors that determine the position and shape of dose-response curves. A convenient measure of the steepness of radiation dose-response curves is the normalized dose-response gradient, gamma, which represents the increase in response, in percentage points, for a 1% increase in dose. Theoretically, the normalized dose-response gradient should increase with increasing clonogenic cell number or, assuming a constant clonogen density, with increasing tumor volume. The aim of this study was to test this hypothesis over a range of tumor volumes and to study how this relationship is affected by heterogeneity in tumor oxygenation. METHODS AND MATERIALS: A C3H mouse mammary carcinoma implanted in the feet of female CDF1 mice was used. Groups of tumors with various volumes were irradiated with single graded radiation doses in air or after making them artificially hypoxic by clamping. The end point used was tumor control defined as complete absence of a macroscopic relapse within 90 days after irradiation. A Poisson dose-response model was assumed to describe tumor control probability in each volume group. The dose needed to control 37% of the tumors (D37) and the normalized dose-response gradient at this dose (gamma37) were estimated by the maximum likelihood method. In another group of animals with tumors in the same volume range, oxygenation status was assessed by a polarographic needle electrode. The percentage of pO2 values <3 mmHg was selected to represent the relative volume of the tumor with radiobiological hypoxia. RESULTS: The D37 values increased as a function of tumor volume under both clamped and ambient conditions. For tumors irradiated under clamped conditions, gamma37 increased with increasing tumor volume throughout the range of volumes studied. However, for tumors irradiated under ambient conditions, there was an initial increase in gamma37 with tumor volume up to 100 mm3 with no further increase beyond that volume. As the tumor volume increased, both the level of hypoxia and the tumor-to-tumor heterogeneity in that level increased. CONCLUSIONS: This study has confirmed the hypothesis that gamma37 increases with increasing tumor volume when tumors are irradiated under clamped condition. The increased heterogeneity of the hypoxic volume fraction with increasing tumor volume could explain why the steepness of the dose-response curve did not increase with increasing tumor volume when irradiation was done under ambient condition. PMID- 9369126 TI - Tumor repopulation during radiotheraphy: quantitation in two xenografted human tumors. AB - PURPOSE: "Accelerated repopulation" has generated considerable recent interest. Our purpose in this study was to determine whether flow cytometry measurements like those used for classical Tpot determinations could be used to quantify the rate of repopulation, and the time of its initiation in irradiated human tumor xenografts. METHODS AND MATERIALS: Two human tumor cell lines (SiHa, a squamous cell cervix carcinoma, and WiDr, an adenocarcinoma of the colon) were grown as subcutaneous xenografts in SCID mice. Tpot was measured in a conventional manner using flow cytometry, for control tumors and for tumors exposed to five fractions of 4 Gy twice daily over a 2-day interval. For the irradiated tumors, Tpot measurements were conducted 48 h following the final exposure. RESULTS: Active proliferation even after irradiation was observed in both the radiosensitive SiHa and more radioresistant WiDr tumors, and the estimated repopulation rate was at least as fast as would have been predicted by the pre-treatment Tpot estimates. CONCLUSIONS: Our data clearly indicate tumor cell proliferation after only a few fractions of radiation exposure in these human tumor xenografts. Additionally, the data suggest that pretreatment Tpot values may underestimate the actual regrowth rate. PMID- 9369127 TI - Pulsed-dose-rate brachytherapy: design of convenient (daytime-only) schedules. AB - PURPOSE: To design pulsed-brachytherapy (PDR) protocols that are expected to be at least as clinically efficacious (in terms of both tumor control and late sequelae) as continuous low-dose-rate (CLDR) regimens, but that involve irradiation only during extended office hours. Both interstitial and intracavitary brachytherapy protocols are considered. METHODS AND MATERIALS: The linear quadratic formalism was used in which the late normal tissue damage and tumor control for one protocol relative to another are assumed to be determined primarily by the level of cellular survival. PDR schedules were designed in which pulses are delivered during "extended office hours" (8 A.M. to 8 P.M.) with no irradiation overnight. Generally, the proposed PDR regimes last the same number of treatment days as the corresponding CLDR regimen, but the PDR treatment lasts longer on the final day (i.e., until 8 P.M.). PDR doses were calculated such as to produce a tumor control which is equivalent to standard CLDR protocols, and the corresponding predicted late complication rate was compared with that for CLDR. Ranges of plausible values for the half-times of sublethal damage repair for tumors and for late-responding normal tissues were considered. RESULTS: As has been previously shown, the efficacy of PDR relative to CLDR depends considerably on the repair rates for sublethal damage repair. Clinical and experimental evidence suggests that average repair half-times for early effects (e.g., tumor control) are less than about a half hour, and for late sequelae are more than about an hour. If these estimates are correct, daytime PDR regimes can usually be designed which take the same number of days as the corresponding CLDR regimen, but have comparable or better therapeutic ratios than CLDR. CONCLUSION: Protocols for PDR can be designed to involve irradiation only during extended office hours, that are likely to result in clinical results comparable or better than CLDR, for any expected combination of the repair half-times of early- and late-responding tissues. The suggested protocols allow all of the advantages of a computerized remote-controlled afterloader while preserving the benefits of low dose rate. In addition, the protocols could allow the patient to go home overnight, or to stay overnight in an adjacent medical inn or hospital-associated hotel, rather than in a hospital bed-which could have major economic benefits. In such an economic situation, an extra treatment day for the daytime PDR could well be considered, which would virtually guarantee an improved clinical advantage relative to CLDR. PMID- 9369128 TI - Effects of cytotoxic chemotherapeutic agents on split-dose repair in intestinal crypt cells. AB - PURPOSE: Many cancer chemotherapeutic agents interact with radiation to enhance the amount of radiation damage observed in both tumor and normal tissues. It is important to predict this interaction and to determine the effect of drug on sublethal damage repair. To evaluate for effects in rapid renewing normal tissues, the intestinal crypt cell in vivo assay is an excellent one to employ. These studies investigate the effect of eleven cancer chemotherapeutic drugs on split-dose repair in the intestinal crypt cell of the mouse. METHODS AND MATERIALS: LAF1 male mice, age 10-12 weeks, were exposed to whole-body irradiation with orthovoltage x-rays delivered as a single dose or as equally divided doses delivered with intervals between the two exposures of 2 to 24 h. In the experimental group, the cancer chemotherapeutic agent was administered intraperitoneally 2 h before the first radiation dose. At 3.6 days after the second irradiation, the mice were sacrificed; the jejunum was removed, fixed, and sectioned for light microscopy. The number of regenerating crypts were counted and corrected to represent the number of surviving cells per circumference. RESULTS: Of the eleven drugs tested, only carmustine eliminated split-dose repair. Cisplatin delayed repair, and methotrexate caused marked synchronization obliterating the observation of split-dose repair. CONCLUSIONS: Most cytotoxic chemotherapeutic agents do not inhibit sublethal damage repair in intestinal crypt cells when given 2 h before the first radiation exposure. Absence of the initial increase in survival seen with split-dose radiation is noted with carmustine and high-dose methotrexate. PMID- 9369129 TI - Concomitant infusion cisplatin and hyperfractionated radiotherapy for locally advanced nasopharyngeal and paranasal sinus tumors. AB - PURPOSE: This is a prospective study to improve the therapeutic ratio in the treatment of patients with locally advanced nasopharyngeal and paranasal sinus tumors by using split-course concomitant infusion cisplatin chemotherapy and hyperfractionated radiotherapy. METHODS AND MATERIALS: From 1983 to 1993, 21 patients with locally advanced nasopharyngeal and paranasal sinus tumors (T3 and T4, or recurrent tumors involving the facial bones and/or the base of the skull) were treated with a regimen of split-course hyperfractioned radiotherapy (1.2 Gy/fraction/bid) and concomitant infusion cisplatin (5-10 mg/m2/24 h). The therapy was given in three separate 2-week sessions with 1 to 2 week breaks between sessions. Seventeen of 21 patients were treated with curative intent with cumulative radiation doses ranging from 64.8 to 70.8 Gy. Four patients were treated with palliative intent to a total dose of less than 60 Gy or to a limited field due to previous irradiation. RESULTS: Sixteen of 17 patients (94%) treated curatively achieved a complete response. Of the 16 patients who achieved complete response, 7 patients (50%) were alive at the time of analysis (36 to 126 months). One patient was alive at 4 years with no evidence of disease, and died in 10 years at the age of 80 of unknown cause. Two patients died of local recurrence at 21 and 45 months and one patient died of a cerebrovascular accident at 12 months with disease status unknown. Five patients died of distant metastases. The one patient who had a partial response died in 25 months with local disease and metastases to the bone and lung. Four patients that were previously irradiated received a reduced total dose or treated to a limited irradiation field. All had near complete responses, but died within a year of treatment, with the exception of one patient who died at 23 months. Acute reactions included intense erythema of the mucosa in all patients. Five of 21 (23%) developed punctate mucositis and 3 of 21 (14%) developed confluent mucositis. Hematologically, one patient developed neutropenia (1800 WBC/mm3) and one developed thrombocytopenia (38,000/mm3). A rising creatinine was observed in three patients (2.0, 1.7, 1.7) all of whom were treated with the higher 10 mg/m2/day dose of infusional cisplatin. In all three of these cases, the creatinine slowly returned to normal over a 6-month period. Hormonal evaluations were performed in three patients and all were within normal ranges. There was no evidence of neck fibrosis or trismus. One patient with gross recurrent disease of the orbit developed blindness of the involved eye due to corneal opacification. The orbital area had been reirradiated in this patient. CONCLUSIONS: Concomitant infusion cisplatinum with hyperfractionated radiation improved tumor control, but did not increase normal tissue injury. Acute reactions were minimized by splitting the treatment with a 1 to 2-week break after each 2 weeks of radiation treatment. Late complications were not increased by using a hyperfractionated radiation regimen. The local failure rate was only 18% (3 of 17 patients), but the distant failure rate was 35% (6 patients). Further investigation is needed to prove if adjuvant chemotherapy after concomitant chemoradiation improves survival by decreasing the distant failure in such advanced cases. PMID- 9369130 TI - Applying radiobiological principles to combined modality treatment of head and neck cancer--the time factor. AB - PURPOSE: Combined modality treatment is indicated for most advanced stage head and neck cancers. It is postulated that the efficacy of combined modality regimens could be enhanced by applying principles derived from radiotherapy fractionation studies to optimize the time factor in treatment scheduling. METHODS AND MATERIALS: The premise that tumor clonogens surviving a therapeutic intervention undergo accelerated repopulation in a time-dependent fashion as their numbers are depleted is used as a model to interpret the results of various chemoradiotherapy and postsurgical radiotherapy protocols and to suggest ways in which future combined modality regimens can be more rationally designed. RESULTS: Meta-analyses of chemoradiotherapy trials show the general superiority of concomitant vs. neoadjuvant sequential protocols. There is also emerging evidence that both the duration of postoperative radiotherapy and the delay in its instigation affect treatment outcome. These results are compatible with the hypothesis that the overall duration of the "package deal" of combined modality treatment is an important determinant of outcome. However, a large decrease in duration of the "package deal" does not necessarily translate into a therapeutic gain because the total dose has to be lowered to prevent intolerable acute reactions. In these circumstances tumor control will improve only if the reduced treatment time circumvents more tumor cell regeneration than the cytoreduction that could be achieved by the extra dose tolerable in a longer time period. More modest reductions in treatment time can be accomplished without dose reduction and so avoid this risk. The design of new protocols should take account of the fact that regeneration of tumor clonogens can be predicted to be nonuniform with time. Thus, the greatest therapeutic gain should be achieved by targeting periods of maximal regenerative capacity for shortening or, alternatively, for intensification of treatment. These periods are the latter part of a course of radiotherapy or chemotherapy and the early postoperative phase after surgery. CONCLUSIONS: The rational design of combined modality protocols should include principles concerning the time factor derived from radiotherapy fractionation studies. Periods of maximal tumor cell regeneration should be targeted for shortening or for treatment intensification. Any dose sacrifice necessitated by reducing treatment duration must be less than the dose equivalent of regeneration during the same time period. PMID- 9369131 TI - Biweekly dose escalation in curative accelerated hyperfractionation for advanced head and neck cancer: a feasibility study. AB - PURPOSE: To study the feasibility of a dose-escalated accelerated hyperfractionation schedule for patients with advanced head and neck cancer. MATERIALS AND METHODS: Twenty-nine previously untreated patients with advanced squamous cell carcinoma were treated with the following biweekly dose-escalated accelerated hyperfraction schedule: during the first 2 weeks 1.2 Gy twice a daily (bid) up to 24 Gy, thereafter during the next following 2 weeks 1.4 Gy bid to 28 Gy in 20 fractions, and thereafter 22.4 Gy in 1.6 Gy bid fractions during 1 1/2 weeks. Thus, the the total dose was 74.4 Gy in 54 fractions given in 5 1/2 weeks. RESULTS: The planned total dose was given within the planned time to 19 (66%) patients. For seven patients the treatment time was prolonged with 1 to 6 days because of department closure for holidays or machine-down days, and in three cases the treatment time was prolonged more than 8 weeks. When the tumor responses were evaluated at 3 months after given radiotherapy, 27 (93%) patients showed complete tumor clearance, 1 patient had a recidual focus, and 1 patient showed progressive disease. The ultimate 1-, 2-, and 3-year local control rates were: 87, 71, and 60%. Four patients had a salvage laryngectomy. The 1-, 2-, and 3-year survival rates for all patients were as follows: 96, 81, and 73%. All patients developed confluent mucositis, 15 patients were hospitalized for nutritional support, and 11 patients had moist desquamation. However, all acute reactions healed completely, and no serious late complications were observed. CONCLUSIONS: This is a safe and effective treatment schedule for patients with advanced head and neck cancer. PMID- 9369132 TI - The potential impact of CT-MRI matching on tumor volume delineation in advanced head and neck cancer. AB - PURPOSE: To study the potential impact of the combined use of CT and MRI scans on the Gross Tumor Volume (GTV) estimation and interobserver variation. METHODS AND MATERIALS: Four observers outlined the GTV in six patients with advanced head and neck cancer on CT, axial MRI, and coronal or sagittal MRI. The MRI scans were subsequently matched to the CT scan. The interobserver and interscan set variation were assessed in three dimensions. RESULTS: The mean CT derived volume was a factor of 1.3 larger than the mean axial MRI volume. The range in volumes was larger for the CT than for the axial MRI volumes in five of the six cases. The ratio of the scan set common (i.e., the volume common to all GTVs) and the scan set encompassing volume (i.e., the smallest volume encompassing all GTVs) was closer to one in MRI (0.3-0.6) than in CT (0.1-0.5). The rest volumes (i.e., the volume defined by one observer as GTV in one data set but not in the other data set) were never zero for CT vs. MRI nor for MRI vs. CT. In two cases the craniocaudal border was poorly recognized on the axial MRI but could be delineated with a good agreement between the observers in the coronal/sagittal MRI. CONCLUSIONS: MRI-derived GTVs are smaller and have less interobserver variation than CT-derived GTVs. CT and MRI are complementary in delineating the GTV. A coronal or sagittal MRI adds to a better GTV definition in the craniocaudal direction. PMID- 9369133 TI - Predictive assays of radiation response in patients with head and neck squamous cell carcinoma: a review of the Institute Gustave Roussy experience. AB - PURPOSE: The aim of the study was to present the updated Institut Gustave Roussy experience of the predictive value of three biological parameters in patients with squamous cell carcinoma of the Head and Neck (HNSCC) treated with radiation therapy. METHODS AND MATERIALS: Three parameters have been investigated independently: tumor cell kinetics (TS, Tpot and LI), oxygen tension measurements (PO2) and intrinsic radiosensitivity (SF2Gy). RESULTS: No relationship has been found between local-regional control and Tpot or LI in a series of 74 patients. Our data also support that the surviving fraction at 2 Gy, (SF2) was unlikely to predict the clinical outcome in a series of 92 patients. Differences in PO2 measurements have been observed between tumors, and tumor oxygenation was lower than that of normal tissue for the majority of patients. However PO2 measurements did not predict clinical outcome, but further investigations are needed to draw definitive conclusions, given the limited number of patients entered in our study (35 patients). In addition, we were able to measure the three parameters in 10 patients showing no correlation between PO2, SF2 and Tpot. CONCLUSIONS: The method used to evaluate Tpot and SF2 did not provide clinically relevant predictive parameters for this type of cancer. Further investigations are needed to assess the predictive value of PO2 measurements and of new biological parameters in a multiparametric approach, taking into account other possible clinical and biological confounding factors. PMID- 9369134 TI - Pharmacokinetic monitoring and dose modification of etanidazole in the RTOG 85-27 phase III head and neck trial. AB - PURPOSE: To prospectively evaluate the pharmacokinetic monitoring and drug dose adjustment of Etanidazole (Eta) in patients treated on the RTOG randomized trial for Stage III and IV head and neck cancer. METHODS AND MATERIALS: From June, 1986 to October, 1991, 521 patients were randomized to conventional RT alone or RT plus Eta. The primary goal was to determine whether the addition of Eta to conventional radiation therapy improves local-regional control and tumor-free survival. Of the 264 patients who received Eta, 233 had their drug exposure calculated and the Eta dose and schedule adjusted accordingly to prevent the occurrence of serious peripheral neuropathy. Drug exposure was assessed using the area under the curve (AUC) for a single treatment that was calculated by the integral over time of the serum concentration of Eta. The total drug exposure (total-AUC) was estimated by multiplying the AUC by the number of drug administrations. RESULTS: Eighteen percent of patients developed Grade I and 6% developed Grade II peripheral neuropathy. There was no Grade 3 or 4 peripheral neuropathy. There is a trend for an increased risk of neuropathy by single dose AUC. The minimal difference in incidence of neuropathy by single-dose AUC was due to the use of dose and schedule modification for patients with the higher values. CONCLUSIONS: The pharmacokinetics investigated in this study confirm previous work that monitoring Eta levels, with dose adjustment, allows it to be used safely in the clinic. In a subset analysis there was a statistically significant improvement in local-regional control and survival rates for patients with N0 and N1 disease, that will require confirmation (14). However, the clinical efficacy of Eta in this trial proved to be of little overall benefit. PMID- 9369135 TI - When is a negative study not negative? AB - Results of Phase III randomized clinical trials can be categorized into three groups: positive, null, and negative. The jargon used in discussing results of comparative studies requires clarification because misclassification can result in incorrect interpretation. A positive result indicates that the experimental therapy(ies) is(are) superior to standard therapy. A null result indicates that no statistically significant difference between therapies was found; hence, standard therapy should not be replaced. A negative result indicates that the experimental therapy had a deleterious effect compared to standard therapy. This article presents a discussion of these categories and examples of each. PMID- 9369136 TI - Planning, delivery, and quality assurance of intensity-modulated radiotherapy using dynamic multileaf collimator: a strategy for large-scale implementation for the treatment of carcinoma of the prostate. AB - PURPOSE: To improve the local control of patients with adenocarcinoma of the prostate we have implemented intensity modulated radiation therapy (IMRT) to deliver a prescribed dose of 81 Gy. This method is based on inverse planning and the use of dynamic multileaf collimators (DMLC). Because IMRT is a new modality, a major emphasis was on the quality assurance of each component of the process and on patient safety. In this article we describe in detail our procedures and quality assurance program. METHODS AND MATERIALS: Using an inverse algorithm, we have developed a treatment plan consisting five intensity-modulated (IM) photon fields that are delivered with DMLC. In the planning stage, the planner specifies the number of beams and their directions, and the desired doses for the target, the normal organs and the "overlap" regions. Then, the inverse algorithm designs intensity profiles that best meet the specified criteria. A second algorithm determines the leaf motion that would produce the designed intensity pattern and produces a DMLC file as input to the MLC control computer. Our quality assurance program for the planning and treatment delivery process includes the following components: 1) verification of the DMLC field boundary on localization port film, 2) verification that the leaf motion of the DMLC file produces the planned dose distribution (with an independent calculation), 3) comparison of dose distribution produced by DMLC in a flat phantom with that calculated by the treatment planning computer for the same experimental condition, 4) comparison of the planned leaf motions with that implemented for the treatment (as recorded on the MLC log files), 5) confirmation of the initial and final positions of the MLC for each field by a record-and-verify system, and 6) in vivo dose measurements. RESULTS: Using a five-field IMRT plan we have customized dose distribution to conform to and deliver 81 Gy to the PTV. In addition, in the overlap regions between the PTV and the rectum, and between the PTV and the bladder, the dose is kept within the tolerance of the respective organs. Our QA checks show acceptable agreement between the planned and the implemented leaf motions. Correspondingly, film and TLD dosimetry indicates that doses delivered agrees with the planned dose to within 2%. As of September 15, 1996, we have treated eight patients to 81 Gy with IMRT. CONCLUSION: For complex planning problems where the surrounding normal tissues place severe constraints on the prescription dose, IMRT provides a powerful and efficient solution. Given a comprehensive and rigorous quality assurance program, the intensity-modulated fields can be efficaciously and accurately delivered using DMLC. IMRT treatment is now ready for routine implementation on a large scale in our clinic. PMID- 9369137 TI - Cost benefit of emerging technology in localized carcinoma of the prostate. AB - PURPOSE: In a health care environment strongly concerned with cost containment, cost-benefit studies of new technology must include analyses of loco-regional tumor control, morbidity, impact on quality of life, and financial considerations. METHODS AND MATERIALS: This nonrandomized study analyzes 124 patients treated with three-dimensional conformal radiation therapy (3D CRT) and 153 with standard irradiation (SRT) between January 1992 and December 1995, for histologically proven adenocarcinoma of prostate, clinical Stage T1 or T2. Mean follow-up is 1.4 years. Three-dimensional CRT consisted of six or seven coplanar oblique and lateral and, in some patients, AP fields designed to treat the prostate with a 1 to 1.7 cm margin. SRT consisted of 120 degrees bilateral arc rotation. Total doses to prostate were 67 to 70 Gy when pelvic lymph nodes were irradiated or 68.4 to 73.8 Gy when prostatic volume only was treated; dose per fraction was 1.8 Gy. Patients were interviewed weekly for severity of 12 acute intestinal and urinary pelvic irradiation side effects (0 to 4+ grading). Time and effort for 3D RTP and daily treatment with 3D CRT and SRT were recorded. Dose volume histograms (DVHs) were calculated for gross tumor volume, planning target volume, bladder, and rectum. Actual reimbursement to the hospital and university was determined for 41 3D CRT, 43 SRT, and 40 radical prostatectomy patients treated during the same period. RESULTS: Average treatment planning times (in minutes) were: 101 for 3D conformal therapy simulation, 66 for contouring of target volume and sensitive structures, 55 for virtual simulation, 39 for plan preparation and documentation, 65 for physical simulation, and 20 for approval of treatment plan. Daily mean treatment times were 19 min for 3D CRT with Cerrobend blocking, 16 with multileaf collimation, and 10 with bilateral arc rotation. Dosimetric analysis (DVHs) showed a reduction of 50% in volume of bladder or rectum receiving doses higher than 65 Gy. Acute side effects included dysuria, moderate difficulty in urinating, and nocturia in 25-39% of both SRT and CRT patients; loose stools or diarrhea in 5-12% of 3D CRT and 16-22% of SRT patients; moderate proctitis in 3% of 3D CRT and 12% of SRT patients (p = 0.01). Chemical disease-free survival (prostate-specific antigen < or =2 ng/ml) at 3 years was 90% with 3D CRT and 80% with SRT (p = 0.01). Average initial treatment reimbursements were $13,823 (3D CRT), $10,864 (SRT), and $12,250 (radical prostatectomy). Average total treatment reimbursement and projected cost of management of initial therapy failures per patients were $15,173, $16,264, and $16,405, respectively. CONCLUSIONS: Three-dimensional CRT irradiated less bladder and rectum volume than SRT; CRT initial reimbursement was 28% higher than SRT and 12% higher than radical prostatectomy. Because of projected better local tumor control, average total cost of treating a patient with 3D CRT or radical prostatectomy is equivalent to cost of SRT. Treatment morbidity was lower with 3D CRT. Our findings reflect an overall benefit with 3D CRT as a new promising technology in treatment of localized prostate cancer. Dose-escalation studies may enhance its efficacy and cost benefit. PMID- 9369138 TI - Radiation techniques for the treatment of Hodgkin's disease with combined modality therapy or radiation alone. AB - This article reviews radiation techniques including field arrangements, anatomic borders, and doses for the treatment of Hodgkin's disease when radiotherapy is being used as the sole treatment and when it is part of a planned combined modality program with chemotherapy. We describe the techniques currently in use at Duke University Medical Center. Particular emphasis is placed on the evidence regarding the appropriate extent of the treatment field and the doses of radiation necessary to achieve local control. These issues assume increasing importance as we attempt to maintain high cure rates for Hodgkin's disease but lower the frequency of serious long-term complications. PMID- 9369139 TI - Cardiac function, perfusion, and morbidity in irradiated long-term survivors of Hodgkin's disease. AB - PURPOSE: The incidence of cardiotoxicity and clinical cardiac events following mantle irradiation (RT) in patients with Hodgkin's disease using modern techniques is controversial. The use of quantitative, prognostically validated noninvasive tests to assess systolic and diastolic cardiac function and regional myocardial blood flow may reveal preclinical abnormalities associated with subsequent clinical events of myocardial infarction, cardiac death, or angina. The goals of this study are to determine, through noninvasive measures, the presence and time course of alterations in cardiac systolic and diastolic function and of relative myocardial blood flow in long-term survivors of Hodgkin's disease, and assess their correlation with subsequent clinical cardiac end points. METHODS AND MATERIALS: Equilibrium radionuclide angiocardiography (ERNA) was used to assess left ventricular (LV) systolic and diastolic function by measuring LV ejection fraction (LVEF) and peak filling rate (PFR), respectively, in patients without known ischemic heart disease who received RT. Electrocardiography was performed to assess electrical cardiac function under conditions of rest and either exercise or dipyridamole vasodilator stress. Quantitative rest/stress myocardial perfusion imaging with thallium-201 and/or Tc 99m sestamibi was used to assess myocardial perfusion. Patients at least 1.0 year after RT were eligible if they were <50 years old at RT, had no known cardiac disease, and remained free of clinical recurrence of Hodgkin's disease. Fifty patients, ages 10.2-46.1 years (mean 26.0 +/- 8.6) at RT, were tested 1.1 to 29.1 years (mean 9.1 +/- 7.5) after RT. Seventeen of these patients were tested two times separated by 1.1 to 8.1 years. The mean central cardiac RT dose was 35.1 +/ 7.8 Gy (range 18.5-47.5) in daily 15-2.0 Gy fractions. Twelve patients were concomitantly irradiated to the left ventricle, usually through partial transmission left lung shields (mean 17.0 +/- 2.2 Gy, range 14.3-21.3). RESULTS: No patients had signs or symptoms of cardiac disease at the time of evaluation. The mean LVEF at the time of initial testing was 59.6 +/- 6.2% (n = 50; range 42 73%; normal > or =50%), and the mean peak filling rate (PFR) was 3.46 +/- 0.88 end diastolic volumes per second (EDV/s) (range 1.5-5.4 EDV/s; normal > or =2.54 EDV/s). The 12 patients also treated to the left ventricle had a normal mean ejection fraction that was lower (56.6 +/- 5.0%) than that of the other 38 patients (LVEF = 60.6 +/- 6.3%, p = 0.051) when initially evaluated. Average PFR was similar in the two groups. For the 15 patients who had repeat tests, changes in LVEF were generally modest in individual patients, and there was no change in the group mean. For all patients, no significant association was found between cardiac function indices and age at RT, dose, or interval from RT to testing. Myocardial perfusion scintigraphy demonstrated mild ischemia in one or more segments in two patients, and borderline normal perfusion in three patients. Rest and stress ECG testing demonstrated mild repolarization abnormalities in three, and one patient was abnormal at rest and had nondiagnostic changes with stress. CONCLUSIONS: Patients irradiated to the heart incidental to the treatment of Hodgkin's disease using modern techniques have generally normal measures of left ventricular function and myocardial perfusion. Modest differences in the normal left ventricular ejection fraction observed may be attributable to the cardiac volume irradiated. Some patients may manifest improved cardiac function as time from RT elapses, while a significant deterioration of ejection fraction was not observed and reduction in diastolic peak filling rate is uncommon. The previously reported increased risk of cardiac death may relate to use of older techniques of RT employing higher doses and lack of cardiac shielding, and uncontrolled patient selection with additional behaviors and cardiac risk factors. PMID- 9369140 TI - Theoretical and practical uses of elective systemic (half-body) irradiation after 20 years of experimental designs. AB - This article traces the concept and different uses of systemic (Half-Body) irradiation (HBI) for the last 20 years. It presents both indirect and direct evidence of HBI effectiveness and discusses the various hypothesis that have been advanced to explain its success as a palliative and more recently as an elective therapeutic tool. The article discusses the transition from treating overt to subclinical metastatic disease and recalls the pioneer uses of elective HBI in lung and prostate cancers. Recent uses of elective HBI with a variety of unconventional fractionation schemes are discussed. These include clinical trials (51 patients with lung, esophagus, colorectal, prostate, ovary and endometrial cancers) and animal experiments (1195 C3H mice). An intriguing combination of hyper/hypo fractionated HBI proved to be the less toxic of all the schedules used in animals where mortality data, analyzed by the LQ Model, yielded an alpha/beta ratio of 8.3 Gy, a value generally associated with acutely responding tissue. PMID- 9369141 TI - Treatment outcome after tangential radiation therapy without axillary dissection in patients with early-stage breast cancer and clinically negative axillary nodes. AB - PURPOSE: To determine the risk of nodal failure in patients with early-stage invasive breast cancer with clinically negative axillary lymph nodes treated with two-field tangential breast irradiation alone, without axillary lymph node dissection or use of a third nodal field. METHODS AND MATERIALS: Between 1988 and 1993, 986 evaluable women with clinical Stage I or II invasive breast cancer were treated with breast-conserving surgery and radiation therapy. Of these, 92 patients with clinically negative nodes received tangential breast irradiation (median dose, 45 Gy) followed by a boost, without axillary dissection. The median age was 69 years (range, 49-87). Eighty-three percent had T1 tumors. Fifty-three patients received tamoxifen, 1 received chemotherapy, and 2 patients received both. Median follow-up time for the 79 survivors was 50 months (range, 15-96). Three patients (3%) have been lost to follow-up after 20-32 months. RESULTS: No isolated regional nodal failures were identified. Two patients developed recurrence in the breast only (one of whom had a single positive axillary node found pathologically after mastectomy). One patient developed simultaneous local and distant failures, and six patients developed distant failures only. One patient developed a contralateral ductal carcinoma in situ, and two patients developed other cancers. CONCLUSION: Among a group of 92 patients with early stage breast cancer (typically T1 and also typically elderly) treated with tangential breast irradiation alone without axillary dissection, with or without systemic therapy, there were no isolated axillary or supraclavicular regional failures. These results suggest that it is feasible to treat selected clinically node-negative patients with tangential fields alone. Prospective studies of this approach are warranted. PMID- 9369142 TI - Conservative surgery and radiotherapy for early-stage breast cancer using a lung density correction: the University of Michigan experience. AB - PURPOSE: Although an abundance of reports detail the successful use of definitive radiotherapy of the breast in the treatment in Stage I or II breast cancer, little data have been published concerning the use of lung density correction and its effect upon long-term outcome. As it has been the practice at the University of Michigan to routinely use lung density correction in the dose calculations to the breast, we retrospectively analyzed our results for local control, relapse free, and overall survival. METHODS AND MATERIALS: Clinical records were reviewed of 429 women with Stage I or II breast cancer treated with lumpectomy, axillary dissection, and breast irradiation with or without systemic chemo/hormonal therapy. Tangential radiotherapy fields delivering 45 to 50 Gy were used to treat the entire breast. A boost was delivered in 95% of cases for a total tumor bed dose of 60 to 66 Gy. All treatment plans were calculated using a lung density correction. RESULTS: With a median follow up of 4.4 years, the 5-year actuarial rate of local control with local failure as the only site of first failure was 96% (95% CI 94-98%). Univariate analysis for local failure as only first failure found the following factors to statistically predict for increased risk of breast recurrence: young age (< or =35 years old), premenopausal status, tumor size >2 cm, positive family history, and positive microscopic margins. Multivariate analysis revealed young age and margin status to be the only factors remaining significant for local failure. The 5-year actuarial relapse-free survival was 85% (95% CI 81-89%); overall survival at 5 years was 90% (95% CI 87-94%). CONCLUSIONS: Lung density correction results in rates of local control, disease free, and overall survival at 5 years that compare favorably with series using noncorrected unit density calculations. While we will continue to update our results with increasing follow-up, our 5-year data indicate that the use of lung density correction for dosimetric accuracy does not compromise local control. PMID- 9369143 TI - External radiation therapy and transcatheter iridium in the treatment of extrahepatic bile duct carcinoma. AB - PURPOSE/OBJECTIVE: Review survival, prognostic factors, and patterns of failure in patients with extrahepatic bile duct (EHBD) carcinoma treated with external beam irradiation (EBRT) and transcatheter iridium. METHODS AND MATERIALS: The charts of 24 patients with EHBD cancer treated with EBRT and transcatheter boost were reviewed. All patients had transhepatic biliary tubes or endoprostheses placed. Two patients underwent hemihepatectomy with hepaticojejunostomy formation but had residual disease. Two patients had biopsy proven adenopathy. Five patients had Grade 1 adenocarcinoma, nine Grade 2, six Grade 3, and one Grade 4 disease. Median EBRT dose was 50.4 Gy delivered in 1.8 Gy/day fractions. Median transcatheter boost at 1 cm radius was 20 Gy. Nine patients received concomitant 5-Fluorouracil (5-FU) during EBRT. RESULTS: Median survival was 12.8 months (range 7.5 months to 9 years). Overall 2- and 5-year survival rates were 18.8 and 14.1%, respectively (three disease-free survivors > or =5 years). One patient is still alive without relapse 10 years from diagnosis and 5 years after liver transplantation for liver failure (no cancer in specimen, underlying sclerosing cholangitis). Two additional long-term survivors had no evidence of relapse 6.9 and 8.2 years after diagnosis. Histologic grade, lymph node status, cystic, hepatic, common hepatic or common bile duct involvement, surgical resection, radiation therapy dose, and chemotherapy did not significantly effect survival due to the number of patients analyzed. There was a trend towards improved survival with the addition of 5-FU chemotherapy (5-year survival in two of nine patients, or 22%). Eight of 24 patients (33%) demonstrated radiographic evidence of local recurrence. Distant metastases developed in 6 of 24 (25%) patients. The most common complications were tube related cholangitis (50%) and gastric/duodenal ulceration or bleeding (42%). CONCLUSION: External beam irradiation combined with a transcatheter boost can result in long-term survival of patients with EHBD cancer. Both distant metastases and local recurrence develop in 25-30% of patients despite irradiation. Survival may be improved by using chemotherapy in combination with EBRT to impact disease relapse (local and distant). Because there may be a dose response with irradiation, survival may also be improved by increasing the dose of radiation delivered by transcatheter boost. A Phase II trial is being developed using a combination of 45-50 Gy EBRT with concomitant 5-FU delivered by protracted venous infusion followed by a 25-30 Gy transcatheter boost. PMID- 9369144 TI - Invasive bladder cancer: treatment strategies using transurethral surgery, chemotherapy and radiation therapy with selection for bladder conservation. AB - PURPOSE: Combined modality therapy has become the standard oncologic approach to achieve organ preservation in many malignancies. METHODS AND MATERIALS: Although radical cystectomy has been considered as standard treatment for invasive bladder carcinoma in the United States, good results have been recently reported from several centers using multimodality treatment, particularly in patients with clinical T2 and T3a disease who do not have a ureter obstructed by tumor. RESULTS: The components of the combined treatment are usually transurethral resection of the bladder tumor (TURBT) followed by concurrent chemotherapy and radiation therapy. Following an induction course of therapy a histologic response is evaluated by cystoscopy and rebiopsy. Clinical "complete responders" (tumor site rebiopsy negative and urine cytology with no tumor cells present) continue with a consolidation course of concurrent chemotherapy and radiation. Those patients not achieving a clinical complete response are recommended to have an immediate cystectomy. Individually the local monotherapies of radiation, TURBT, or multidrug chemotherapy each achieve a local control rate of the primary tumor of from 20 to 40%. When these are combined, clinical complete response rates of from 65 to 80% can be achieved. Seventy-five to 85% of the clinical complete responders will remain with bladders free of recurrence of an invasive tumor. CONCLUSIONS: Bladder conservation trials using combined modality treatment approaches with selection for organ conservation by response of the tumor to initial treatment report overall 5-year survival rates of approximately 50%, and a 40-45% 5-year survival rate with the bladder intact. These modern multimodality bladder conservation approaches offer survival rates similar to radical cystectomy for patients of similar clinical stage and age. Bladder-conserving therapy should be offered to patients with invasive bladder carcinoma as a realistic alternative to radical cystectomy by experienced multimodality teams of urologic oncologists. PMID- 9369145 TI - Radiation therapy for macular degeneration: technical considerations and preliminary results. AB - PURPOSE: This study was undertaken to assess the toxicity and possible benefits from the administration of low-dose external-beam irradiation for Age-Related Macular Degeneration (ARMD). The premise of the treatment is that radiation induces regression and/or promotes inactivation of the subretinal neo vasculature, resulting in reabsorption of fluid and blood thus reducing the risk for further leakage or bleeding, as well as subretinal fibrosis. Clinically, the beneficial effect could be translated into stabilization of visual acuity and prevention of progression of the wet type of ARMD with the possibility for some visual improvement. METHODS AND MATERIALS: Allegheny University Hospitals, Hahnemann, Department of Radiation Oncology, treated 278 patients prospectively beginning in January 1995 with low-dose irradiation for wet-type macular degeneration. Two hundred forty-nine patients were treated with a total dose of 14.40 Gy in eight fractions of 1.80 Gy over 10-13 elapsed days, and 27 patients with 20 Gy at 2 Gy per fraction over 12-15 days. The first two patients were treated to a total dose of 10.00 Gy in five fractions of 2.00 Gy. Patients were evaluated at 2-3 weeks and 2-3 months. A percentage (36.7%) of the patients had previously received laser treatments in the study eye, 21.9% once, 5% twice, 9.7% three or more. Subjective visual acuity and toxicity data was collected on all patients. RESULTS: At 2-3 weeks after treatment 195 patients (70%) retained their visual acuity without change, 68 patients (24.5%) stated they had improved vision, and 15 patients (4.8%) stated their vision continued to decrease. Two to 3 months after treatment, 183 patients (65.8%) had no change in their vision, 75 patients (27%) had an improvement in their vision, and 20 patients (7.2%) had a decrease in visual acuity. Transient acute reactions occurred in 14 of the 278 patients treated. CONCLUSION: Our observations in this group of 278 patients support the conclusion that many patients will have improved or stable vision after treatment with low-dose irradiation for age related wet type macular degeneration. PMID- 9369146 TI - Mutant molecular motors disrupt neural circuits in Drosophila. AB - A dominant negative mutation, Glued1, that codes for a component of the dynactin complex, disrupted the axonal anatomy of leg sensory neurons in Drosophila. To examine neuron structure in mutant animals, a P[Gal4] enhancer trap targeted expression of lacZ to the sensory neurons and thereby labeled neurons in the femoral chordotonal organ and their axons within the central nervous system. When these sensory axons were examined in the Glued1 mutant specimens, they were observed to arborize abnormally. This anatomical disruption of the sensory axons was associated with a corresponding disruption in a reflex. Normally, the tibial extensor motor neurons were excited when the femoral-tibial joint was flexed, but this resistance reflex was nearly absent in mutant animals. We used the P[Gal4] insertion strains to target expression of tetanus toxin light chain to these sensory neurons in wild-type animals and showed that this blocked the resistance reflex and produced a phenocopy of the Glued result. We conclude that disruption of the dynein-dynactin complex disrupts sensory axon path finding during metamorphosis, and this in turn disrupts synaptic connectivity. PMID- 9369147 TI - Macrophage activity in organ cultures of the avian cochlea: demonstration of a resident population and recruitment to sites of hair cell lesions. AB - The factors that regulate the repair and regeneration of the sensory hair cells of the inner ear are not understood. Previous studies of hair cell injury in the lateral line sensory organs of amphibians and the cochleae of mammals have demonstrated that macrophages and other leukocytes are recruited to sites of hair cell lesions. The present study examined the distribution and activity of macrophages in organ cultures of the avian cochlea, a system whose regenerative abilities have been widely studied. Cochleae were removed from chicks and placed in organ culture, and precise hair cell lesions were created using a laser microbeam. Macrophages in the cultures were identified using histochemical, immunocytochemical, and morphologic criteria. It was found that (a) cultured cochleae contained a resident population of macrophages, and (b) increased numbers of macrophages were recruited to the sites of hair cell lesions. Furthermore, the latency of macrophage recruitment to lesions is consistent with a suggested role for macrophages in the initiation of hair cell regeneration. PMID- 9369148 TI - Activity-dependent regulation of N-cadherin in DRG neurons: differential regulation of N-cadherin, NCAM, and L1 by distinct patterns of action potentials. AB - Cell adhesion molecule (CAM) expression is highly regulated during nervous system development to control cell migration, neurite outgrowth, fasciculation, and synaptogenesis. Using electrical stimulation of mouse dorsal root ganglion (DRG) neurons in cell culture, this work shows that N-cadherin expression is regulated by neuronal firing, and that expression of different CAMs is regulated by distinct patterns of neural impulses. N-cadherin was down-regulated by 0.1 or 1 Hz stimulation, but NCAM mRNA and protein levels were not altered by stimulation. L1 was down-regulated by 0.1 Hz stimulation, but not by 0.3 Hz, 1 Hz, or pulsed stimulation. N-cadherin expression was lowered with faster kinetics than L1 (1 vs. 5 days), and L1 mRNA returned to higher levels after terminating the stimulus. The RSLE splice variant of L1 was not regulated by action potential stimulation, and activity-dependent influences on L1 expression were blocked by target-derived influences. The results are consistent with changes in firing pattern accompanying DRG development and suggest that functional activity can influence distinct developmental processes by regulating the relative abundance of different CAMs. PMID- 9369149 TI - Expression of c-ret in the zebrafish embryo: potential roles in motoneuronal development. AB - We have isolated and characterized the zebrafish ortholog of c-ret, a gene essential for renal organogenesis and enteric nervous system development in mammals. During zebrafish embryogenesis c-ret transcripts are expressed in a number of tissues including spinal motoneurons, pronephric ducts, cranial ganglia, pharyngeal arches, and the enteric nervous system. We have examined in detail the expression of c-ret during the development of identified spinal primary motoneurons. c-ret expression is regulated in a cell type-specific manner among the three primary motoneurons. c-ret is expressed at its highest levels in caudal primary (CaP) motoneurons and transcripts can be detected shortly before the expression of the CaP-specific gene, islet2. We suggest that c-ret may play a role in specifying CaP cell identity. c-ret is expressed at low levels in the other primary motoneurons and also in a subset of secondary motoneurons, suggesting that it may also play a broader role in motoneuronal survival or maintenance. PMID- 9369150 TI - Gicerin, a cell adhesion molecule, participates in the histogenesis of retina. AB - Gicerin is a novel cell adhesion molecule that belongs to the immunoglobulin superfamily. Gicerin protein adheres to neurite outgrowth factor (NOF), an extracellular matrix protein in the laminin family, and also exhibits homophilic adhesion. Heterophilic adhesion of gicerin to NOF is thought to play an active role in neurite outgrowth of developing retinal cells in vitro. In this study, we examined the adhesion activity of gicerin during the retinal development of Japanese quail using an antibody directed against gicerin, to elucidate the biological importance of gicerin in retinal histogenesis. Immunohistochemical and Western blot analysis showed that gicerin was highly expressed in the developing retina but suppressed in the mature retina. The aggregation of neural retinal cells from 5-day embryonic quail retina was significantly inhibited when incubated with a polyclonal antibody to gicerin, suggesting that gicerin protein participates in the adhesion of neural retinal cells of the developing retina. Furthermore, histogenesis of retina both in the organ cultures and in ovo embryos was severely disrupted by incubation with a gicerin antibody. These findings provide evidence that gicerin plays an important role in retinal histogenesis. PMID- 9369151 TI - Expression of the Na-K-2Cl cotransporter is developmentally regulated in postnatal rat brains: a possible mechanism underlying GABA's excitatory role in immature brain. AB - An inhibitory neurotransmitter in mature brain, gamma-aminobutyric acid (GABA) also appears to be excitatory early in development. The mechanisms underlying this shift are not well understood. In vitro studies have suggested that Na-K-Cl cotransport may have a role in modulating immature neuronal and oligodendrocyte responses to the neurotransmitter GABA. An in vivo developmental study would test this view. Therefore, we examined the expression of the BSC2 isoform of the Na-K 2Cl cotransporter in the postnatal developing rat brain. A comparison of sections from developing rat brains by in situ hybridization revealed a well-delineated temporal and spatial pattern of first increasing and then diminishing cotransporter expression. Na-K-2Cl mRNA expression in the cerebral cortex and hippocampus was highest in the first week of postnatal life and then diminished from postnatal day (PND) 14 to adult. Cotransporter signal in white-matter tracts of the cerebrum, cerebellum, peaked at PND 14. Expression was detected in cerebellar progenitor cells of the external granular layer, in internal granular layer cells at least as early as PND 7, and in Purkinje cells beginning at PND 14. Double-labeling immunofluorescence of brain sections with anti-BSC2 antibody and cell type-specific antibodies confirmed expression of the cotransporter gene product in neurons and oligodendrocytes in the white matter in a pattern similar to that determined by in situ hybridization. The temporal pattern of expression of the Na-K-2Cl cotransporter in the postnatal rat brain supports the hypothesis that the cotransporter is the mechanism of intracellular Cl- accumulation in immature neurons and oligodendrocytes. PMID- 9369152 TI - Calcium/calmodulin-dependent protein kinase II expression in motor neurons: effect of axotomy. AB - Although Ca2+/calmodulin-dependent (CaM) protein kinase II isoforms are present in the nervous system in high amounts, many aspects of in vivo expression, localization, and function remain unexplored. During development, CaM kinase IIalpha and IIbeta are differentially expressed. Here, we examined CaM kinase II isoforms in Sprague-Dawley rat sciatic motor neurons before and after axotomy. We cut the L4-5 spinal nerves unilaterally and exposed the proximal nerve stumps to a fluoroprobe, to retrogradely label the neurons of origin. Anti-CaM kinase IIbeta antibody showed immunoreactivity in motor neurons, which decreased to low levels by 4 days after axotomy. We found a similar response by in situ hybridization with riboprobes. The decrease in expression of mRNA and protein was confined to fluorescent motor neurons. For CaM kinase IIalpha, in situ hybridization showed that the mRNA was in sciatic motor neurons, with a density unaffected by axotomy. However, these neurons were also enlarged, suggesting an up-regulation of expression. Northern blots confirmed an mRNA increase. We were unable to find CaM kinase IIalpha immunoreactivity before or after axotomy in sciatic motor neuron cell bodies, suggesting that CaM kinase IIalpha is in the axons or dendrites, or otherwise unavailable to the antibody. Using rats with crush lesions, we radiolabeled axonal proteins being synthesized in the cell body and used two-dimensional polyacrylamide gel electrophoresis with Western blots to identify CaM kinase IIalpha as a component of slow axonal transport. This differential regulation and expression of kinase isoforms suggests separate and unique intracellular roles. Because we find CaM kinase IIbeta down-regulates during axonal regrowth, its role in these neurons may be related to synaptic transmission. CaM kinase IIalpha appears to support axonal regrowth. PMID- 9369153 TI - Xefiltin, a Xenopus laevis neuronal intermediate filament protein, is expressed in actively growing optic axons during development and regeneration. AB - Neurofilaments are an important structural component of the axonal cytoskeleton and are made of neuronal intermediate filament (nIF) proteins. During axonal development, neurofilaments undergo progressive changes in molecular composition. In mammals, for example, highly phosphorylated forms of the middle- and high molecular-weight neurofilament proteins (NF-M and NF-H, respectively) are characteristic of mature axons, whereas nIF proteins such as alpha-internexin are typical of young axons. Such changes have been proposed to help growing axons accommodate varying demands for plasticity and stability by modulating the structure of the axonal cytoskeleton. Xefiltin is a recently discovered nIF protein of the frog Xenopus laevis, whose nervous system has a large capacity for regeneration and plasticity. By amino acid identity, xefiltin is closely related to two other nIF proteins, alpha-internexin and gefiltin. alpha-Internexin is found principally in embryonic axons of the mammalian brain, and gefiltin is expressed primarily in goldfish retinal ganglion cells and has been associated with the ability of the goldfish optic nerve to regenerate. Like gefiltin in goldfish, xefiltin in Xenopus is the most abundantly expressed nIF protein of mature retinal ganglion cells. In the present study, we used immunocytochemistry to study the distribution of xefiltin during optic nerve development and regeneration. During development, xefiltin was found in optic axons at stage 35/36, before they reach the tectum at stage 37/38. Similarly, after an orbital crush injury, xefiltin first reemerged in optic axons after the front of regeneration reached the optic chiasm, but before it reached the tectum. Thus, during both development and regeneration, xefiltin was present within actively growing optic axons. In addition, aberrantly projecting retinoretinal axons expressed less xefiltin than those entering the optic tract, suggesting that xefiltin expression is influenced by interactions between regenerating axons and cells encountered along the visual pathway. These results support the idea that changes in xefiltin expression, along with those of other nIF proteins, modulate the structure and stability of actively growing optic axons and that this stability is under the control of the pathway which growing axons follow. PMID- 9369154 TI - Retinal axon growth cone responses to different environmental cues are mediated by different second-messenger systems. AB - Numerous studies have shown that the developing tip of a neurite, the growth cone, can respond to environmental cues with behaviors such as guidance or collapse. To assess whether a given cell type can use more than one second messenger pathway for a single behavior, we compared the influence of two well characterized guidance cues on growth cones of chick temporal retinal ganglion cells. The first cue was the repulsive activity derived from the posterior optic tectum (p-membranes), and the second was the collapse-inducing activity derived from oligodendrocytes known as NI35/NI250. p-Membranes caused permanent growth cone collapse with no recovery after several hours, while NI35 caused transient collapse followed by recovery after about 10 min. The p-membrane-induced collapse was found to be Ca2+ independent, as shown using the Ca2+-sensitive dye Fura-2 and by the persistence of collapse in Ca2+-free medium. Dantrolene, a blocker of the ryanodine receptor, had only a minor effect on the collapse frequency caused by p-membranes. In contrast, the NI35-induced collapse was clearly Ca2+ dependent. [Ca2+]i increased sevenfold preceding collapse, and both dantrolene and antibodies against NI35 significantly reduced both the Ca2+ increase and the collapse frequency. Thus, even in a single cell type, growth cone collapse induced by two different signals can be mediated by two different second messenger systems. PMID- 9369155 TI - Glial-derived neurotrophic factor rescues calbindin-D28k-immunoreactive neurons in alcohol-treated cerebellar explant cultures. AB - Ethanol exposure during development leads to alterations in neuronal differentiation and profound neuronal loss in multiple regions of the developing brain. Although differentiating Purkinje cells of the cerebellum are particularly vulnerable to ethanol exposure, the mechanisms that ameliorate ethanol-induced Purkinje cell loss have not been well defined. Previous research indicates that glial-derived neurotrophic factor (GDNF), a member of the transforming growth factor-beta family, promotes the survival of several neuronal populations, including cerebellar Purkinje cells. Therefore, we examined whether GDNF could attenuate ethanol-induced Purkinje cell loss in an in vitro model system using calbindin-D28k immunoreactivity as a specific marker for Purkinje cells. We found that ethanol led to a significant dose-related decline in calbindin-D28k immunoreactive cells in explant cultures of the developing cerebellum. However, concurrent administration of GDNF led to a significant rescue of calbindin-D28k immunoreactive cells. Therefore, our results suggest that GDNF prevents ethanol associated Purkinje cell loss. PMID- 9369156 TI - Astrocytes regulate amino acid receptor current densities in embryonic rat hippocampal neurons. AB - Embryonic rat hippocampal neurons were cultured in a serum-free defined medium (MEM/N3) either directly on poly-D-lysine (PDL) or on a confluent monolayer of postnatal cortical astrocytes, C6 glioma cells, or Rat2 fibroblasts. Neurons on PDL were grown in MEM/N3 or in MEM/N3 conditioned for 24 h by astrocytes or C6 cells. Membrane capacitance (Cm) and gamma-aminobutyric acid (GABA)-, glycine-, kainate-, and N-methyl-D-aspartate (NMDA)-induced currents were quantified using whole-cell patch-clamp recordings. Cm as well as the amplitude and the density of these currents in neurons cultured on astrocytes were significantly greater than those in neurons grown on PDL after 24 and 48 h. C6 cells mimicked astrocytes in promoting Cm and GABA-, glycine-, and NMDA-evoked, but not kainate-evoked, currents. Cm and currents in neurons grown on Rat2 cells were comparable to those in neurons on PDL. Astrocytes maintained in culture for 3 months were noticeably less effective than freshly prepared ones just grown to confluence. Suppression of spontaneous cytoplasmic Ca2+ (Ca[c]2+) elevations in astrocytes by 1,2-bis(2 aminophenoxy) ehane-N, N, N, N-tetraacetic acid acetoxymethyl ester (BAPTA-AM) loaded intracellularly blocked the observed modulatory effects. Medium conditioned by either astrocytes or C6 cells mimicked the effects of direct coculture of neurons on these cells in promoting Cm and amino acid-evoked currents. Inclusion of antagonists at GABA and glutamate receptors in coculture experiments blocked the observed effects. Thus, diffusible substances synthesized and/ or secreted by astrocytes in a Ca(c)2+-dependent manner can regulate neuronal growth and aminoacid receptor function, and these effects may involve neuronal GABA and glutamate receptors. PMID- 9369157 TI - Gap junctions in the ovaries. PMID- 9369158 TI - Polymeric immunoglobulin A receptor in the rodent female reproductive tract: influence of estradiol in the vagina and differential expression of messenger ribonucleic acid during estrous cycle. AB - Previously we have shown that estradiol and progesterone regulate the levels of secretory component, the external domain of polymeric immunoglobin A (IgA) receptor responsible for transporting IgA from tissues into secretions, at both the mRNA and protein levels in the rodent uterus. In the present study, experiments were designed to determine whether polymeric immunoglobulin receptor (pIgR) is synthesized locally in the vagina and whether it is under the control of estradiol and progesterone. Polymeric IgR message corresponding in size to that previously reported in the liver and uterus was detected by Northern blot analysis of total RNA from the vagina. Levels of pIgR mRNA and pIgR in the vagina were found to vary with the stage of the cycle. Polymeric IgR mRNA levels were elevated at diestrus, reduced at estrus, and undetectable at proestrus. Immunohistochemical analysis of pIgR in the vagina indicated that the expression of protein correlated with the mRNA levels. When ovariectomized rats were treated with estradiol, progesterone, or a combination of the two for 3 days, pIgR mRNA levels were significantly reduced in estradiol-treated animals relative to saline treated controls. No significant changes were observed in the pIgR mRNA levels of animals treated with progesterone alone or with a combination of estradiol and progesterone. Polymeric IgR expression analyzed by immunohistochemical staining correlated well with variations in mRNA levels seen following hormone treatment. In situ hybridization localized pIgR in uterine and vaginal epithelial cells. In the uterus, pIgR message was abundant in luminal and glandular epithelial cells at estrus and low at diestrus. In contrast, expression of pIgR mRNA was pronounced in vaginal epithelial cells at diestrus, while very little message could be localized in the epithelium at estrus. These findings demonstrate that pIgR is synthesized locally in the uterus and vagina and is under tissue-specific hormone regulation. PMID- 9369159 TI - Microtubule organization and chromatin configurations in hamster oocytes during fertilization and parthenogenetic activation, and after insemination with human sperm. AB - The cytoskeletal components of hamster oocytes, zygotes, and spontaneously activated parthogenotes were examined after immunocytochemical labeling. Microtubules were found only in the anastral, tangentially arranged second meiotic spindle of unfertilized oocytes. Taxol treatment of unfertilized oocytes greatly augmented astral microtubules in both the metaphase II spindle and the cortex. Disruption of the meiotic spindle microtubules with nocodazole resulted in cortical chromosomal scattering. During hamster sperm incorporation and pronuclear formation, no sperm aster was detected in association with the male DNA. Instead, a large overlapping array of microtubules assembled in the cortex. By mitosis, this interphase array disassembled and an anastral metaphase spindle formed. Microtubule and chromatin configurations were also imaged in hamster oocytes injected with human sperm. Astral microtubules were absent from the sperm centrosome. The implications of these results are discussed in relation to the hamster oocyte penetration assay, a test commonly used by in vitro fertilization clinics to demonstrate the fertilizing ability of human sperm. We conclude that since hamsters and humans follow different methods of centrosome inheritance, maternal and paternal, respectively, the hamster may be an inappropriate model for exploring microtubule and centrosomal defects in humans or for assaying postinsemination forms of human male fertility defects. PMID- 9369160 TI - Relationship between spermatozoan lipid composition and fertility during aging of chickens. AB - Changes in the proportions of the various lipid components in spermatozoa were investigated throughout the reproductive period (24-72 wk of age) of male chickens. Sperm motility and in vivo fertility were also measured, and correlation coefficients with the lipid values were determined. The proportion of total phospholipid (PL) increased to reach a maximum value at 39 wk and decreased significantly thereafter. The relative content of free cholesterol and triacylglycerols showed no change in spermatozoa during aging or in relation to fertility values; free fatty acids and cholesterol esters increased continuously with age. Of the various PL classes, phosphatidylserine and phosphatidylcholine displayed a pattern of changes with age positively and negatively, respectively, in relation to the changes of fertility. The proportion of phosphatidylethanolamine had significantly decreased by the end of the reproductive period. The proportions of C16:0, C18:0, and C18:1n-9 within the PL of the spermatozoa increased with age, and those of C20:4n-6, C22:4n-6, and C22:6n-3 decreased. Positive correlations were found between fertility and total PLs, phosphatidylserine, and PL-bound C20:4n-6 and C22:4n-6; a negative correlation was found between fertility and phosphatidylcholine. Motility was positively correlated with the level of PL and negatively with that of free cholesterol; it was also positively correlated with the levels of C22:4n-6 and C22:6n-3 and negatively with those of C16:0, C18:0, and C18:1n-9. The results suggest that the lipid and fatty acid compositions of spermatozoa may be important predictors of fertility. PMID- 9369161 TI - Oviductal antibody response to a defined recombinant sperm antigen in macques. AB - Macaque oviductal fluids were assayed for specific antibodies to the intra acrosomal sperm protein SP-10 after immunizations with recombinant macaque SP-10 (re-mqSP-10), a candidate contraceptive vaccinogen. Access ports, consisting of a subcutaneous collecting reservoir and a catheter to cannulate the oviduct, were implanted into monkeys for repeated aspiration of oviductal fluid. Monkeys were inoculated i.m. once a month with an emulsion consisting of 2 mg re-mqSP-10 in a vehicle of squalene and mannin monooleate. Oviductal fluids and serum were collected during the periovulatory period for six menstrual cycles, and IgG and IgA antigen-specific antibodies in preimmune and immune fluids were compared by ELISA. Both relative and absolute concentrations of SP-10-specific immunoglobulins (Ig) were determined. Oviductal fluids from immunized animals showed significant increases in anti-SP-10 IgG at cycle 2 and at all subsequent intervals. Anti-SP-10 IgA significantly increased in oviductal fluid at cycles 4, 5, and 6. Serum anti-SP-10 IgG increased at cycle 2 and remained significantly elevated through cycle 6, while serum anti-SP-10 IgA was higher than in preimmune samples at cycle 4. Serum antibodies generated to the recombinant SP-10 recognized SP-10 extracted from macaque sperm on Western blots. Immunocytochemical staining of macaque and human sperm showed acrosomal immunofluorescence with both immune oviductal fluids and serum using both anti IgG and anti-IgA secondary antibodies. This study demonstrates for the first time 1) IgG and IgA antibodies to a defined recombinant sperm-specific antigen in primate oviductal fluids after systemic immunization and 2) the recognition by primate oviductal fluid IgG and IgA of the endogenous contraceptive target on both human and macaque sperm. PMID- 9369162 TI - Follicle-stimulating hormone enhances the development of preantral follicles in juvenile rats. AB - The stimulatory effects of gonadotropins on antral and preovulatory follicles are well known, but conflicting results have been reported regarding the gonadotropin responsiveness and dependency of preantral follicles. Taking advantage of the relatively uniform development of the first wave of follicles in the postnatal rat ovary, we evaluated the role of endogenous and exogenous gonadotropins on preantral follicle development. Reduction of the high levels of gonadotropins present in juvenile rats by either hypophysectomy (at Day 15) or GnRH antagonist treatment (starting from Day 11 of age) resulted in decreased ovarian weight at Day 19 of age that was associated with a reduced number of developing follicles and increased atresia of remaining follicles. In contrast, treatment with FSHctp (a long-acting FSH agonist) in intact (Days 5-19 of age), hypophysectomized (Days 15-19), or GnRH antagonist-treated (Days 11-19) animals resulted in increased ovarian weight and follicle development as determined histologically and by inhibin-alpha expression. A dose-dependent stimulatory effect of hCG on ovarian weight was seen when animals were cotreated with FSHctp and the GnRH antagonist. At low doses of hCG, augmentation of antral follicle formation occurred, whereas higher doses of hCG led to morphological signs of luteinization. These findings demonstrate the important role of endogenous gonadotropins in preantral follicle development and indicate that preantral follicles are highly responsive to exogenous gonadotropins. PMID- 9369163 TI - Correlation between binding affinities of C21 steroids for the maturation inducing steroid membrane receptor in spotted seatrout ovaries and their agonist and antagonist activities in an oocyte maturation bioassay. AB - The relative binding affinities of steroids for the maturation-inducing steroid (MIS) plasma membrane receptor in spotted seatrout (Cynoscion nebulosus) ovaries were compared to their relative potencies in inducing final oocyte maturation (FOM) of seatrout oocytes in vitro. The MIS receptor is specific for C21 steroids (pregnenes) lacking ketone or hydroxyl (OH) groups at the 11 position. The addition of single OH groups at the 17, 20, or 21 positions and two OHs at the 17, 20 and at the 17, 21 positions of both progesterone and pregnenolone derivatives decreased binding affinity. In contrast, the combination of OH at the 20beta and 21 positions increased affinity, and greatest binding affinity for a progesterone derivative was observed with three OHs at positions 17, 20beta, and 21 (17,20beta,21-trihydroxy-4-pregnen-3-one; 20beta-S), the natural MIS in this species. Germinal vesicle breakdown (GVBD) bioassays showed that 1-min exposure to 290 nM 20beta-S or 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P) in vitro was sufficient to induce final maturation of follicle-enclosed oocytes of seatrout and a closely related species, Atlantic croaker (Micropogonias undulatus), whereas the other steroids tested were ineffective. 20Beta-S was more potent than 17,20beta-P in inducing GVBD after 1-min exposure at lower steroid concentrations (5 nM-100 nM), even though the follicular uptake of the two steroids was similar. Coincubation of seatrout oocytes for 1 min with other steroids at concentrations capable of displacing more than 80% of the bound 20beta-S from its receptor effectively blocked the induction of GVBD by 5 nM 20beta-S. The binding affinities of steroids for the MIS receptor correlated in general with either their agonist or their antagonist activities in the GVBD bioassays. These findings strongly support the concept that induction of FOM by the MIS in spotted seatrout is mediated solely through the ovarian plasma membrane 20beta-S receptor. PMID- 9369164 TI - Long-term entrainment of circannual reproductive and metabolic cycles by Northern and Southern Hemisphere photoperiods in woodchucks (Marmota monax). AB - Woodchucks were exposed to simulated Northern Hemisphere (boreal) or Southern Hemisphere (austral) natural photoperiods in groups of 17 males and 17-18 females at 20-23 degrees C for 69 mo and examined monthly. Photoentrainment of endogenous cycles was evaluated based on dates of peak body weight, peak testis volume, increased serum testosterone in males, and increased serum progesterone in females. Boreal photoperiods entrained and synchronized annual cycles in 15 of 17 males and in all 17 females; 2 males never entrained and free-ran at 9- to 11-mo intervals. Austral photoperiods phase-advanced cycles by approximately 6 mo after 2.5 yr in 34 of 35 animals. Four entrained males became refractory after 4 yr, free-running at 6- to 10-mo intervals. Photoentrained boreal animals became phase advanced by 1 mo during the first 2 yr, and then had 12-mo cycles for 4 yr. In Year 5, on average, boreal cycles included initial testosterone elevations in mid January (vs. mid-July in australs), parturition in early March (vs. early September in australs), and peak body weight in mid-July (vs. late January in australs). The results confirm that endogenous circannual cycles of woodchucks can be entrained and synchronized for 6 yr by daily changes in photoperiod similar to those of midnorthern latitudes, and can be re-entrained and phase advanced 6 mo by photoperiods of midsouthern latitudes. PMID- 9369165 TI - Prostaglandin F2alpha induces expression of prostaglandin G/H synthase-2 in the ovine corpus luteum: a potential positive feedback loop during luteolysis. AB - The primary role of prostaglandin (PG) F2alpha in regression of the corpus luteum has been clearly demonstrated in many mammalian species. We have used in vivo and in vitro approaches to investigate the possibility that exogenous PGF2alpha induces expression of prostaglandin G/H synthase-2 (PGHS-2; cyclooxygenase-2) and causes production of PGF2alpha in ovine luteal cells. Ewes received infusions into the ovarian artery of 1 ml PGF2alpha (1 micromol) or saline, and corpora lutea were collected at various times and analyzed for PGHS-2 mRNA using quantitative, competitive reverse transcription polymerase chain reaction. PGF2alpha dramatically increased the steady-state concentration of mRNA for PGHS 2 within 1 h, but basal concentration returned at 12 h posttreatment. In vitro studies using isolated ovine large luteal cells indicated that mRNA for PGHS-2 was induced by PGF2alpha, phorbol didecanoate, and ionomycin in a pattern similar to that observed in vivo. PGHS-2 protein was induced by all three treatments 4-12 h later, and accumulation of PGF2alpha in the culture media increased at 12 and 24 h posttreatment. In conclusion, we have provided evidence that PGF2alpha, probably acting through the protein kinase C/free intracellular calcium pathway, can stimulate large luteal cells to express PGHS-2 and produce PGF2alpha. This luteal PGF2alpha is likely to have an autocrine/paracrine function to augment the luteolytic effect of PGF2alpha of uterine origin. PMID- 9369166 TI - Deterioration of goat sperm viability in milk extenders is due to a bulbourethral 60-kilodalton glycoprotein with triglyceride lipase activity. AB - The aim of this work was to purify, identify, and characterize the component of goat bulbourethral gland secretion (BUS) responsible for goat sperm deterioration in skim milk extender. BUS extracts promote a decrease in the percentage of motile spermatozoa, deterioration in the quality of movement, breakage of acrosomes, and cellular death of goat spermatozoa diluted in skim milk. A 55- to 60-kDa monomeric glycoprotein (BUSgp60) was purified by cation-exchange, concanavalin A, and heparin-affinity chromatography and was identified as the only BUS component responsible for the deterioration of spermatozoa in milk. The BUSgp60 was shown to display triacylglycerol hydrolase activity, and partial sequences (37 amino acids in all) exhibited 50-70% homology with sequences of various types of pancreatic lipases (PLs), especially PL-related protein 2 (PL RP2). In addition, porcine PL produced deterioration of goat sperm properties in milk as effectively as BUS and BUSgp60. These results support the preliminary identification of the goat BUSgp60 as a bulbourethral lipase belonging to the PL RP2 family. Since seminal plasma also contains factors favorable for sperm survival, it is envisaged that, for the best preservation of goat semen, specific inhibitors of this family of lipase could be added into milk-based extenders without eliminating seminal plasma. PMID- 9369167 TI - Cyclooxygenase-2 unlike cyclooxygenase-1 is highly expressed in ovine embryos during the implantation period. AB - In this study we investigated expression of the two isoforms of the prostaglandin forming enzyme, cyclooxygenase-1 (Cox-1) and cyclooxygenase-2 (Cox-2), in sheep embryos. Using Western blot and immunohistochemical analyses, we demonstrated that Cox-2 was highly expressed in embryos from Day 8 to Day 17 of development whereas Cox-1 was undetectable during this time. The expression of Cox-2 was developmentally regulated. It was maximal between Days 14 and 16. There was a 30 fold increase in Cox-2 content per protein extract between Day 10 and Day 14, corresponding to a 50,000-fold increase in the whole embryo. The expression of Cox-2 declined after Day 16 to become undetectable by Day 25 of pregnancy. Cox-2 was localized in the trophoblastic cells and was not detected in the inner cell mass. The [3H]arachidonic acid metabolites synthesized by Cox-2-rich conceptuses were analyzed by HPLC after short-term embryo culture. Day 14 conceptuses released mainly cyclooxygenase metabolites and to a lesser extent lipoxygenase derivatives. Cyclooxygenase products were 6-keto-prostaglandin (PGF)1alpha 18.2% (+/- 4.2), thromboxane-B2 22.51% (+/- 15.9), PGF2alpha 21% (+/- 11), PGE2 14.5% (+/- 7.4), and PGD2 2.7% (+/- 2.6). Taken together, these results suggest an important role for the Cox-2-dependent cyclooxygenase metabolites during embryo development. PMID- 9369168 TI - Timing of compaction and inner cell allocation in bovine embryos produced in vivo after superovulation. AB - Preimplantation development in the bovine embryo was examined by relating the occurrence of three morphogenetic processes (compaction, blastulation, and hatching) to the timing of allocation of embryonic cells to the inner cell mass (ICM) or to the trophectoderm (TE). Embryos were collected from 26 cows between Days 4 and 9 postovulation. Compaction started 5 days postovulation at the 32 cell stage. Morulae remained firmly compact until the seventh cell cycle was almost completed. Blastocyst formation started between the 64- and 128-cell stage at Days 6, 7, and 8 postovulation. Hatching was predominant at Day 9 postovulation. ICM and TE cells could successfully be distinguished by differential staining in 107 of 142 embryos (75%). Inner cells could first be detected in 20% of 16-cell embryos. Unexpectedly, it was found that inner cell allocation and compaction were independent processes, since 31% of compacted morulae displayed no ICM. Beyond the 50-cell stage, in vivo compact morulae displayed at least 10 ICM cells, whereas blastocysts with a minimum total cell number of 65 cells displayed at least 23 ICM cells. It can be concluded that the slow in vivo transition from the morula to the blastocyst stage allows sufficient time for allocation of inner cells to the ICM of the embryo. PMID- 9369169 TI - Positive effect of partial zona-pellucida dissection on the in vitro fertilizing capacity of cryopreserved C57BL/6J transgenic mouse spermatozoa of low motility. AB - Although cryopreservation of mouse spermatozoa has recently become available for use, as yet there are considerable differences in fertilization efficiency of cryopreserved spermatozoa among various mouse strains. In this study, oocytes subjected to partial dissection of the zona pellucida (PZD) were inseminated with frozen-thawed C57BL/6J mouse spermatozoa. At 30, 60, 120, and 240 min after insemination, the oocytes were washed in human tubal fluid medium and cultured for 3-6 h. The fertilization rates of the PZD oocytes in each group at 6-7 h after insemination were significantly higher than that of the zona-intact control (73-88% vs 12%, respectively) (p < 0.01); but the incidence of polyspermy was nevertheless quite low (1.3-2.4%). The development rates of the monospermic oocytes to the morula and early blastocyst stages were in the 87-92% range, with 31-40% of those developing into offspring after embryo transfer. When the cryopreserved spermatozoa of C57BL/6J transgenic mice were used to fertilize PZD oocytes, the fertilization rates were as high as (73-76%) those of the PZD oocytes inseminated with the cryopreserved C57BL/6J spermatozoa, with 30-31% of the morulae and early blastocysts derived from the monospermatic oocytes developing into offspring. These results indicate that PZD of oocytes may provide an alternative when the fertilizing capacity of mouse spermatozoa has been compromised by cryopreservation. PMID- 9369170 TI - Thioredoxin messenger ribonucleic acid is regulated by estradiol in the rat uterus. AB - Thioredoxin is a major cellular dithiol reductant with a large number of functions in electron transport and thiol redox control of enzymes and transcription factors. To investigate the expression and regulation of thioredoxin in the uterus, 35 rats were ovariectomized (OVX) and treated 14 days after surgery with either growth hormone (GH), dexamethasone (DEX), or estradiol (E2), or combinations of these, for 24 h. Thioredoxin mRNA levels were determined by solution hybridization. The animals receiving E2 or a combination of E2 and DEX showed significantly increased thioredoxin mRNA levels, by 4-fold and 5-fold, respectively, as compared to the OVX control group. The GH or GH+DEX-treated groups did not display any difference in thioredoxin mRNA levels. Thioredoxin mRNA was also measured at different time points in uteri from OVX rats treated with daily E2 injections and was found to be transiently increased, with a maximum 48 h after the initiation of the E2 treatment. In contrast, the thioredoxin mRNA level in the liver of OVX rats was about 10-fold higher than in the uterus but remained unaffected by the different hormone treatments. We conclude that thioredoxin mRNA is expressed in the rat uterus, and up-regulated by E2 in a tissue-specific manner, with a maximum at 48 h after the initiation of hormone treatment. PMID- 9369171 TI - Granulocyte-macrophage colony-stimulating factor promotes development of in vitro produced bovine embryos. AB - The objective was to determine whether granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates development of bovine embryos. In each experiment, oocytes were fertilized in vitro, GM-CSF was added to embryo culture medium at 8 10 h or 5 days after insemination, and development was monitored as the proportion of oocytes that formed blastocysts. Addition of recombinant bovine GM CSF to serum-free medium at 8-10 h after insemination increased the percentage of oocytes that formed blastocysts (7.2% and 15.2% for control and GM-CSF, respectively). GM-CSF did not affect cleavage rate. Rather, the effect of GM-CSF seems to be exerted after Day 5 after insemination, as indicated by the following findings: 1) GM-CSF did not alter embryo cell number at Day 5 after insemination; 2) administration of GM-CSF at Day 5 increased the proportion of oocytes that developed to the blastocyst stage (6.7%, 13.0%, and 22.4% for control and 1 and 10 ng/ml GM-CSF, respectively); and 3) addition of serum at Day 5 increased development but prevented a further increase due to addition of GM-CSF at 10 h after insemination. Blastocysts from GM-CSF-treated cultures tended to be at earlier stages of morphological development (i.e., fewer blastocysts expanded at Day 7 and fewer were hatching or hatched at Day 9 after insemination). GM-CSF may play a role in the early development of bovine embryos and might be a useful molecule for increasing blastocyst production rates in serum-free culture systems. PMID- 9369172 TI - Functional interrelationships between follicles greater than 4 mm and the follicle-stimulating hormone surge in heifers. AB - The interrelationships between the FSH surge that initiates a follicular wave and the follicles in the wave were examined in heifers. In experiment 1, > or = 5-mm follicles were ablated 5 days after ovulation and heifers (n = 6/group) received a total dosage of 0, 37.5, 75, or 150 units of porcine FSH. Half of the FSH dosage was administered 24 h after ablation followed by the other half 12 h later. Blood samples were taken after the initial FSH injection for FSH assay, and ovaries were examined daily with ultrasound to monitor follicle growth. There were progressively higher FSH concentrations at the mean peak (8 h after initial injection in all groups) as the dosage increased (interaction of dose and time; p < 0.001). Compared to values in controls, the highest dosage (150 units) approximately doubled the number of 5- and 6-mm follicles; this then progressed into a 4- to 7-fold increase in the number of 7- and 8-mm follicles. In experiment 2, either all (controls; n = 6), two (n = 11), one (n = 6), or zero (n = 6) follicles of the first wave of an estrous cycle were retained and the remaining were ablated upon reaching 5 mm. Scanning and blood sampling were performed every 8 h for 72 h after the initial ablation. Mean FSH concentrations during 0 to 72 h decreased (p < 0.004) as the number of retained follicles increased. In heifers in the one-follicle group, the randomly chosen 5-mm follicle developed the characteristics of a dominant follicle. The following conclusions were made: 1) the number of follicles that advanced into a follicular wave was increased by exaggerating the height of the FSH surge, 2) all > or = 5 mm follicles of a wave contributed to the declining portion of the FSH surge, and 3) any 5-mm follicles at the emergence of a wave were capable of becoming the dominant follicle. PMID- 9369173 TI - Effect of pituitary adenylate cyclase-activating peptide on meiotic maturation in follicle-enclosed, cumulus-enclosed, and denuded rat oocytes. AB - Pituitary adenylate cyclase-activating polypeptide (PACAP) is a novel bioactive peptide isolated from ovine hypothalamus. Recently, its presence and action have been demonstrated also in peripheral tissues such as testis and ovary. On the basis of sequence similarity, PACAP is included in the vasoactive intestinal peptide (VIP)/glucagon/secretin/growth hormone-releasing factor (GRF) family of neuropeptides. Because both VIP and GRF stimulate oocyte maturation in the rat ovary, we wanted to evaluate whether PACAP also could influence this process. Granulosa cells and follicle-enclosed, cumulus-enclosed, and denuded oocytes were obtained from immature eCG-treated rats. The addition of PACAP-38 significantly accelerated meiotic maturation in follicle- and cumulus-enclosed oocytes from treated rats and in follicle enclosed-oocytes from immature untreated rats, while VIP was effective only on follicle-enclosed oocytes. Interestingly, when used on denuded oocytes, PACAP was able to directly affect the meiotic process. In fact, the neuropeptide delayed oocyte maturation by maintaining elevated levels of intracellular cAMP. Our results clearly demonstrate an involvement of PACAP in oocyte meiotic maturation. Furthermore, for the first time, a direct effect of a peptide on the oocytes has been shown. Moreover, the differences in the action of PACAP and VIP on granulosa cells and oocytes suggest the presence of PACAP type I receptors on both cell types. Our results, along with the data demonstrating the presence of the peptide in the ovary, strongly suggest a potential relevance of PACAP in ovarian physiology. PMID- 9369174 TI - Major proteins of bovine seminal plasma modulate sperm capacitation by high density lipoprotein. AB - Bovine seminal plasma (BSP) contains four similar proteins secreted by the seminal vesicles, designated BSP-A1, -A2, -A3, and -30 kDa. These proteins bind to choline phospholipids on the surface of the sperm after ejaculation. These BSP proteins also interact with heparin, apolipoprotein A-I (apoA-I) and apoA-I associated with high-density lipoprotein (HDL). The HDL and heparin present in the female reproductive tract have been implicated in sperm capacitation and the acrosome reaction (AR). This study was undertaken to determine whether or not these BSP proteins and HDL could modulate the capacitation of sperm, and to determine the combined effect of HDL and heparin on capacitation. Washed bovine epididymal sperm were preincubated in buffer containing BSP proteins, washed, and incubated with lipoproteins (HDL, and low- and very low-density lipoproteins) or liposomes with or without apoA-I in the presence or absence of heparin. The percentage of capacitated sperm was evaluated after the AR was induced with lysophosphatidylcholine. HDL alone (160 microg/ml) after an 8-h incubation stimulated the AR of epididymal sperm. The percentage of HDL-enhanced AR further increased when sperm were preincubated with BSP proteins. ApoA-I-liposomes stimulated the AR more rapidly (5 h, 160 microg/ml) than HDL. When sperm were preincubated with BSP proteins, the percentage of apoA-I-enhanced AR further increased. In contrast, when liposomes without apoA-I or when low- or very low density lipoproteins or lipoprotein-depleted serum was used, no significant increase in the AR was detected with or without BSP proteins. When heparin and HDL or apoA-I-liposomes were used together, their combined effects on the AR were not additive. These results indicate that BSP proteins modulate the process of capacitation induced by heparin, HDL, and apoA-I-liposomes. PMID- 9369175 TI - Isolation of pluripotent stem cells from cultured porcine primordial germ cells. AB - Embryonic germ (EG) cells are undifferentiated stem cells isolated from cultured primordial germ cells (PGC). To date, EG cells have been isolated only in the mouse. Murine EG cells share several characteristics with embryonic stem (ES) cells, including morphology, pluripotency, and the capacity for germline transmission. We report here the isolation of porcine EG cells. PGC collected from Day 24 or 25 porcine embryos were cultured on mitotically inactivated murine fibroblasts. Four EG cell lines were isolated from repeated subculture of porcine PGC. Porcine EG cells morphologically resembled murine ES cells and consistently expressed alkaline phosphatase activity. These cell lines maintained a normal diploid karyotype and survived after cryopreservation. Porcine EG cells were capable of differentiating into a wide range of cell types in culture, including endodermal, trophoblast-like, epithelial-like, fibroblast-like, and neuron-like cells. In suspension culture, porcine EG cells formed embryoid bodies. When injected into host blastocysts, the EG cells were able to differentiate and contribute to tissues of a chimeric piglet. Both in vitro and in vivo evidence demonstrates that the isolated EG cells were pluripotent. These cells are potentially useful for genetic manipulation in pigs. PMID- 9369176 TI - Expression of bcl-2 and nr-13 in hen ovarian follicles during development. AB - Follicle atresia is initiated within the granulosa cell layer of ovarian follicles and is mediated via the process of apoptosis. In the hen, at least two populations of granulosa cells can be distinguished during follicle development on the basis of their inherent susceptibility or resistance to apoptosis, in vitro. Given the previously established correlation between expression of bcl xLong and hen granulosa cell resistance to apoptosis, the present studies were conducted to characterize expression of bcl-2 and an avian bcl-2 homologue, nr 13, in follicles at various stages of development. Levels of nr-13 mRNA were significantly higher only in granulosa cells from the largest (F1) preovulatory follicle compared to 3- to 5-mm prehierarchal follicles. By comparison, bcl-2 mRNA levels were 5- to 9-fold higher in granulosa cells from the three largest preovulatory follicles compared to those from follicles 9 to 12 mm in diameter and prehierarchal follicles. The increase in neither nr-13 nor bcl-2 was correlated with the stage of follicle development associated with the acquisition of resistance to apoptosis in granulosa cells (e.g., at the 9- to 12-mm stage). Results from the present studies do not support a close correlation between constitutive expression of nr-13 or bcl-2 mRNA and the transition from a state of apoptosis susceptibility to apoptosis resistance in hen granulosa cells. Thus, it is proposed that nr-13 and bcl-2 play more of a supportive role in regulating additional aspects of ovarian cell function such as cell proliferation and/or differentiation. PMID- 9369177 TI - Characterization of the equine glycoprotein hormone alpha-subunit gene reveals divergence in the mechanism of pituitary and placental expression. AB - The equine glycoprotein hormone alpha-subunit gene is expressed in both pituitary and placenta, unlike that of all other nonprimate mammals studied, in which expression is limited to pituitary. Previous studies of the 5'-flanking region of the equine alpha-subunit promoter have revealed unique characteristics as well as similarities with the human alpha-subunit promoter, which demonstrates a similar pattern of tissue-specific expression. We have cloned and sequenced the equine alpha-subunit gene and have used tissue culture systems and transgenic mice to characterize its expression. Unlike the human promoter, the cloned equine alpha subunit promoter failed to direct trophoblast-specific expression in either tissue culture or transgenic mouse models, suggesting an entirely different mechanism for expression. In contrast, the equine alpha-subunit promoter was able to direct gonadotroph expression in both tissue culture and transgenic mouse models. In alphaT3-1 cells, 550 base pair (bp) was sufficient for expression. This expression involves promoter elements identified in other species as playing a role in gonadotroph expression, but mutation of these elements reveals differences in their relative contributions to promoter activity. In mice, 2800 bp of 5'-flanking sequence allowed specific expression in gonadotrophs but not in thyrotrophs or placenta. The pattern of estrogen regulation observed in transgenic mice matched neither the repression that has been observed with human and bovine alpha-subunit promoters in transgenic mice nor the stimulation in mRNA levels reported in mares, suggesting a unique mechanism that is not recapitulated in the transgenic model. Thus the equine alpha-subunit promoter uses a combination of conserved and unique features of gene regulation to direct its pattern of tissue-specific expression. PMID- 9369178 TI - Antimicrobial protection of the mouse testis: synthesis of defensins of the cryptdin family. AB - We report the synthesis by mouse testicular cells of antibiotic peptides related to the defensins secreted by the Paneth cells of the intestinal epithelium. A Sertoli cell-derived line (15P-1), Sertoli cells in primary cultures, and explanted testicular tissue in culture medium were observed to release protease sensitive material with a broad-spectrum antibacterial activity. The activity of 15P-1 culture medium was increased 10- to 50-fold in the presence of fractions enriched in round spermatids and of nerve growth factor. Two series of results suggest that this activity may correspond to the release by testicular cells of defensin peptides, and specifically, of peptides of the cryptdin family first identified in the Paneth cells of intestinal crypts. First, a characteristic nucleotide sequence corresponding to the conserved first exon of the mouse cryptdin and cryptdin-related (CRS) genes was evidenced in the RNA of 15P-1 cells and of the testis. Second, immunohistochemical analysis demonstrated the presence of cryptdins of the cryp-1, -2, -3, -6 group in 15P-1 cells, and identified two distinct localizations in the testis. Inside the seminiferous tubule, these cryptdins were found accumulated in Sertoli cells at stages corresponding to the maturation of spermatids. In the interstitial space, Leydig cells also contained immunoreactive cryptdins. PMID- 9369179 TI - Complete activation of porcine oocytes induced by the sulfhydryl reagent, thimerosal. AB - Thimerosal (200 microM) triggered Ca2+ oscillations in 56 of 56 mature porcine oocytes. The Ca2+ oscillations were blocked by the sulfhydryl-reducing agent dithiothreitol (DTT), thus supporting the hypothesis that thimerosal acts by oxidizing critical sulfhydryl groups on intracellular Ca2+-release proteins. Thimerosal treatment alone arrested the oocytes in metaphase, probably by oxidizing tubulin sulfhydryl groups and thus destroying the spindle. However, a 10-min exposure to 200 microM thimerosal followed by a 30-min incubation in 8 mM DTT induced complete activation, as 73.8% of the oocytes formed pronuclei. The second polar body was visible in 73.3% (55 of 75) of the activated oocytes. Combined thimerosal/DTT treatment of the oocytes also induced cortical granule exocytosis, as revealed by confocal microscopy, and the subsequent hardening of the zona pellucida. After activation, some oocytes were incubated in vitro, or in vivo in a ligated porcine oviduct, for 6 days. When cultured in vitro, 42.0% (37 of 88) of the oocytes developed to the compact morula or blastocyst stage; the average number of inner cell mass (ICM) and trophectoderm (TE) nuclei in the blastocysts was 8.6 +/- 0.7 and 20.1 +/- 1.3, respectively. Culture in a ligated oviduct resulted in 42.9% development to the compact morula or blastocyst stage, with the blastocysts having a mean number of 12.5 +/- 1.0 ICM and 63.6 +/- 9.2 TE nuclei. PMID- 9369180 TI - Identification of a promoter region generating Sry circular transcripts both in germ cells from male adult mice and in male mouse embryonal gonads. AB - The mouse testis determining gene Sry is expressed in somatic cells of the differentiating male gonad as a linear transcript, encoding a transcription factor containing an HMG box. In the adult mouse testis, Sry expression occurs in meiotic and postmeiotic germ cells. The mouse genomic Sry locus is characterized by two arms of a large inverted repeat, flanking a unique region that, between an acceptor and a donor splice site, contains a single exon encoding the Sry protein. In germ cells from the adult mouse testis, Sry RNA is a circular molecule, which is generated by an inverted splicing event that utilizes the above-mentioned splice sites. Thus, a circular exon is spliced out starting from a large linear RNA precursor containing both arms of the inverted repeat, which pair and generate a large stem-loop structure. Using reverse transcription polymerase chain reaction and an RNase protection assay, we have now mapped the 5' end of this precursor RNA in the 5' arm of the inverted repeat. Gel mobility shift assay and in vitro transcription with nuclear extracts from adult germ cells further confirm that a region immediately 5' upstream of two transcriptional initiation sites of the precursor RNA contains a promoter sequence in which two consensus Sry binding sequences are specifically recognized by nuclear factors present in adult germ cells but not in Sertoli cells. We also show that the linear precursor of the Sry circular transcript and its splicing product are specifically expressed not only in adult germ cells but also in male embryonal gonads between 11.5 and 13.5 days postcoitum, immediately after the expression of the linear transcript starting from the unique region. PMID- 9369181 TI - Biochemical characterization of sperm agglutination antigen-1, a human sperm surface antigen implicated in gamete interactions. AB - The anti-sperm monoclonal antibody (mAb) S19 was previously demonstrated to agglutinate human spermatozoa, inhibit sperm penetration of cervical mucus, and inhibit sperm-zona pellucida binding. These results implicated the cognate S19 antigen, designated sperm agglutination antigen-1 (SAGA-1), in gamete interactions and identified SAGA-1 as an attractive candidate for immunocontraceptive development. In the present study, evaluation of sperm agglutination with video microscopy showed that the S19 mAb rapidly and completely agglutinated human spermatozoa in a "tangled" pattern of agglutination. One- and two-dimensional immunoblot analyses identified SAGA-1 as a highly acidic, polymorphic sperm protein with an apparent molecular mass of 15 25 kDa and an isoelectric point of 2.5-3.0. Periodate treatment abolished this immunoreactivity, demonstrating that the S19 mAb reacted with a carbohydrate epitope and indicating that SAGA-1 is a glycoprotein. Absence of S19 immunoreactivity in postvasectomy seminal fluid implicated the testis, epididymis, and/or proximal vas deferens in the expression of SAGA-1. In solubility and phase partitioning assays, SAGA-1 was extracted from spermatozoa in Triton X-114 and exhibited the hydrophobic characteristics of integral and glycosylphosphatidyl inositol-anchored membrane proteins. These results identify SAGA-1 as a hydrophobic, highly acidic sperm glycoprotein that is localized on the entire sperm surface and has potential significance as a target for antibodies that inhibit sperm function and gamete interactions. PMID- 9369182 TI - Preovulatory changes in the levels of three gonadotropin-releasing hormone encoding messenger ribonucleic acids (mRNAs), gonadotropin beta-subunit mRNAs, plasma gonadotropin, and steroids in the female gilthead seabream, Sparus aurata. AB - Gilthead seabream females undergo daily cycles of final oocyte maturation (FOM), ovulation, and spawning throughout their spawning season. FOM consists of lipid droplet and yolk granule coalescence, germinal vesicle (GV) migration, and GV breakdown. Plasma maturational gonadotropin (GtH-II) levels fluctuate throughout the day, reaching a peak at 8 h before spawning, when the GV is at the periphery of the oocyte. The preovulatory GtH-II surge is accompanied by an increase in the plasma levels of 17alpha,20beta-dihydroxy-4-pregnen-3-one and estradiol, while testosterone and 17alpha,20beta,21-trihydroxy-4-pregnen-3-one levels remain unchanged. Concurrent with the preovulatory GtH-II surge, there is an increase in pituitary GtH-II beta subunit mRNA levels followed by an increase in GtH-Ibeta mRNA levels. Gilthead seabream brain contains three different forms of GnRH: salmon (s)GnRH, seabream (sb)GnRH, and chicken (c)GnRH-II. All three GnRH encoding mRNAs fluctuate throughout the day, reaching highest levels 8 h before spawning, concurrent with the preovulatory GtH-II surge. On the basis of these correlations and of the anatomical organization of the three GnRH systems, it is hypothesized that in the daily-spawning gilthead seabream females, preovulatory GtH-II secretion, and probably synthesis, are induced by a surge of sbGnRH secretion. The involvement of the other two GnRH forms, sGnRH and cGnRH-II, in the control of ovulation and spawning is presumed, on the basis of the elevation of their mRNA levels at the time of the preovulatory GtH-II secretion and spawning. PMID- 9369183 TI - Modifications of carbohydrate residues and ZP2 and ZP3 glycoproteins in the mouse zona pellucida after fertilization. AB - Oligosaccharide side chains of zona pellucida (ZP) glycoproteins play a key role in the sperm-egg interaction phenomena during fertilization. In the present study, modifications of the ZP glycoproteins during the fertilization process in the mouse were studied by the lectin-gold technique and immunocytochemistry in conjunction with quantitative analysis. Binding of PNA, RCA I, DSA, LFA, MAA, AAA, and anti-ZP2 and anti-ZP3 antibodies was observed throughout the ZP of both unfertilized and fertilized eggs. However, HPA and BSAIB4 labeling was found only in the inner region of the ZP. After neuraminidase treatment (Neu), HPA showed an affinity for the entire ZP. Labeling by LFA, WGA, MAA, PNA, BSAIB4, and AAA decreased in the ZP of fertilized eggs; however, there was an increase in the binding of RCA I. HPA and Neu-HPA increased only in the inner region of the ZP. Immunoreactivity to antibodies against ZP2 and ZP3 also decreased after fertilization. The present results demonstrate that 1) terminal carbohydrate residues contained in the ZP glycoproteins are modified after fertilization and 2) inner and outer regions of the ZP contain different oligosaccharide side chains. PMID- 9369184 TI - Location, immunohistochemical features, and spinal connections of autonomic neurons innervating the rat seminal vesicles. AB - With the use of retrograde tracing techniques, selective spinal nerve transections, and immunohistochemistry to label noradrenergic and peptidergic pathways, this study has for the first time defined in detail the autonomic innervation to the rat seminal vesicles. The majority of this innervation originates from the bilateral major pelvic ganglia, whereas very few neurons are located in the accessory, inferior mesenteric, or paravertebral chain ganglia. Neuropeptide Y was the most abundant marker, followed by tyrosine hydroxylase (an enzyme involved in noradrenaline synthesis), and then vasoactive intestinal peptide. Sympathetic axons with tyrosine hydroxylase and neuropeptide Y supplied vascular and nonvascular smooth muscle whereas parasympathetic, cholinergic neuropeptide Y terminals were associated with the glandular epithelium. In contrast, vasoactive intestinal peptide was found only in cholinergic neurons, which may have either parasympathetic or sympathetic spinal connections. The latter were far more prevalent, demonstrating a substantial sympathetic cholinergic innervation to the seminal vesicles. Vasoactive intestinal peptide axons were associated with the glandular epithelia, as well as vascular and nonvascular smooth muscle. Axons associated with the secretory epithelia may regulate secretion or perhaps provide trophic support. Finally, acute damage to preganglionic sacral and lumbar nerves caused a transient increase in glandular weight. PMID- 9369185 TI - The alpha1B-adrenergic receptor subtype activates the phospholipase C signaling pathway in rat myometrium at parturition. AB - This study demonstrates that alpha1-adrenergic receptors previously identified in the pregnant rat myometrium are heterogeneous. They can be subtyped alpha1A- and alpha1B-adrenergic receptors on the basis of their affinity for the antagonists WB4101 (alpha1A > alpha1B) and chloroethylclonidine (alpha1B selective). Between Day 21 of pregnancy and term, the proportion of [3H]prazosin binding sites with low affinity for WB4101 and sensitive to inactivation by 10(-5) M chloroethylclonidine under hypotonic conditions (alpha1B subtype) remained constant. In contrast, the number of [3H]prazosin binding sites with a high affinity for WB4101 and insensitive to chloroethylclonidine (alpha1A subtype) increased by 88% at term. The effect of 5'-guanylylimidodiphosphate (Gpp[NH]p) on competition of the agonist phenylephrine for [3H]prazosin binding in the presence of WB4101 or after chloroethylclonidine pretreatment indicates that the alpha1A adrenergic receptor underwent uncoupling whereas the alpha1B-adrenergic receptor G protein coupled state was increased (+ 63%). Phenylephrine consistently stimulated phospholipase C activity on membrane fractions prepared from term myometria. This stimulation was completely inhibited after 10(-5) M chloroethylclonidine but was not consistently decreased with 5-methylurapidyl, a selective alpha1A-antagonist. Furthermore QL antibody (anti-G alpha(q)/G alpha11) also specifically blocked the phenylephrine-stimulated phospholipase C activity. Altogether these results strongly suggest that activation of the alpha1B adrenergic receptor subtype in the pregnant myometrium at term may contribute to the stimulation of the G alpha(q)/G alpha11/phospholipase C signaling pathway. PMID- 9369186 TI - Ovarian morphology and endocrine characteristics of female sheep fetuses that are heterozygous or homozygous for the inverdale prolificacy gene (fecX1). AB - The Inverdale gene (fecX1), located on the X chromosome, is a major gene affecting the ovulation rate of sheep. At each ovulation, ewes heterozygous (I+) for the fecX1 gene ovulate, on average, one more egg than noncarriers (++), whereas ewes that are homozygous (II) for this gene are infertile and have "streak" ovaries. Since formation of the ovary occurs in fetal life, it is possible that the fecX1 gene influences ovarian development before birth. The aims of this study were to examine the effects of the fecX1 gene on germ cell development, follicular formation and growth, and plasma gonadotropin concentrations at 5 different days of gestation (i.e., Days 40, 90, 105, 120, and 135) and also in adult life. The results suggest that one copy of the X-linked mutation in female fetuses leads to a retardation of germ cell development at Days 40 and 90 of gestation. However, from Day 105 of gestation, follicular formation and growth appear normal. By contrast, in females with two copies of the X-linked mutation, germ cell development and follicular formation appear normal, but thereafter follicular growth from the primary stage of development is impaired. During fetal life the plasma concentrations of FSH and LH, although not measurable at Day 40, were similar between all the genotypes at Day 105, 120, and 135 of gestation. The only exception was for LH at Day 90 in the I+ and II animals: in ewes with these genotypes the plasma concentrations of LH were similar but significantly lower (p < 0.01) than in the ++ genotype. In adult animals the plasma concentrations of FSH and LH were not different between the ++ and I+ genotypes, reflecting similar levels of ovarian follicular activity. However, in adult II animals, the plasma concentrations of FSH and LH were significantly higher (both p < 0.01) than in the ++ and I+ genotypes, reflecting the absence of normal secondary and antral follicles. In summary, these data show that the fecX1 gene affects ovarian development before birth and that the nature of the effect is influenced by whether the female fetus is a homozygous or heterozygous carrier of the X-linked mutation. PMID- 9369187 TI - Significance of apoptosis in the temporal and stage-specific loss of germ cells in the adult rat after gonadotropin deprivation. AB - The major objectives of the present study were to document the temporal and stage specific acceleration of germ cell apoptosis in adult rats after selective suppression of pituitary gonadotropins by GnRH antagonist (GnRH-A) treatment, and to examine the possibility that apoptosis is the sole mechanism of germ cell death in response to hormonal deprivation. Groups of adult male rats were given a daily injection of a vehicle for 14 days or GnRH-A (1.25 mg/kg BW) for 2, 5, 7, and 14 days. Analysis of testicular apoptotic DNA fragmentation revealed a detectable increase at Day 5 and a maximal increase at 14 days after treatment. In situ analysis of germ cell apoptosis fully corroborated the observed increase in the degree of DNA fragmentation with time and also revealed a stage-related activation of apoptosis of specific germ cells. A low incidence (0.06-0.09) of germ cell apoptosis (expressed as numbers per Sertoli cell) was detectable at stages I, IX-XI, and XII-XIV in control rats. Mean incidence of apoptotic germ cells specifically at stages VII-VIII increased significantly (0.40 +/- 0.06) by Day 5 and increased another 2.2-fold (over the 5-day treatment values) on Day 7 after GnRH-A treatment as compared to values in controls, where no apoptosis was detected. Significantly increased incidence of apoptosis at stages IX-XI (0.37 +/ 0.05) over control values (0.07 +/- 0.01) was noted by Day 7. Within the study paradigm, the highest number of dying cells occurred by Day 14, at which time a modest but significant (p < 0.05) increase in the incidence of apoptosis was also noted at stages I, II-IV, V-VI, and XII-XIV in comparison with control values. Stages VII-VIII and IX-XI still exhibited the higher number of cells undergoing apoptosis (0.97 +/- 0.22, and 1.03 +/- 0.22, respectively). Comparison between rates of apoptosis and cell degeneration measured at stages VII-VIII demonstrated an intimate association (r = 0.94; p < 0.001) between apoptosis and germ cell loss, strongly supporting the concept that germ cell death (at these stages) after removal of hormonal support in the adult rat occurs almost exclusively via apoptosis. PMID- 9369188 TI - Presence of functional luteinizing hormone/chorionic gonadotropin (hCG) receptors in human breast cell lines: implications supporting the premise that hCG protects women against breast cancer. AB - We investigated MCF-7 and MDA-MB-231 human breast cancer cell lines and immortalized mammary epithelial HBL-100 cells for the presence of functional LH/hCG receptors. The results revealed that all three breast cell lines contain LH/hCG receptor mRNA transcripts and receptor proteins that can bind 125I-hCG. The MCF-7 cells, however, contain higher levels than the others. Culturing MCF-7 cells with highly purified hCG resulted in a dose- and time-dependent significant decrease in steady-state estradiol receptor mRNA and protein levels as compared to controls, with the maximal decrease occurring after 4 h of culture with 10 ng/ml hCG. The studies on cell growth demonstrated that hCG treatment in the presence of minimal or no fetal bovine serum had a time-dependent significant inhibitory effect on MCF-7 and HBL-100, but not on MDA-MB-231 cells. In summary, our results demonstrate that human breast cell lines contain functional LH/hCG receptors. The hCG effects in MCF-7 cells are consistent with a premise that hCG protects women against breast cancer. PMID- 9369189 TI - Characterization of intrafollicular steroid hormones, inhibin, and follistatin in women with and without polycystic ovarian syndrome following gonadotropin hyperstimulation. AB - The etiology of polycystic ovary syndrome (PCOS) is unexplained. Since no major deficiencies are reported in serum FSH or inhibin, we hypothesized that abnormal levels of a paracrine modulator of FSH action within the ovary may be associated with the arrest of follicular growth seen in the PCOS ovary. Follicular fluid aspirates were collected from women with (n = 7) or without (n = 17) PCOS during oocyte retrieval for in vitro fertilization. Aspirates were assayed for total inhibin, inhibin A (InhA), inhibin B (InhB), and follistatin (FS), as well as for estradiol, progesterone (P4), androstenedione, and total protein. Hormone levels were compared between women with and without PCOS using all aspirates (some of which were collected from multiple follicles at once) and also between aspirates containing fluid from a single follicle only (PCOS, n = 30; non-PCOS, n = 107). P4 levels were significantly (p < 0.01) reduced in PCOS versus non-PCOS women as evidenced by analysis of all follicles as well as in single-follicle aspirates only. In addition, InhA, P4, and FS increased with follicle volume, and InhB decreased significantly in non-PCOS, but not in PCOS, follicles. Therefore, although follicular development can be induced in PCOS patients with gonadotropins, hormonal responses within the ovary appear inappropriate in terms of concentrations or patterns of secretion. These data support the concept that PCOS is associated with a deficit in the paracrine control of folliculogenesis. PMID- 9369190 TI - Cytotoxic activity of endometrial granulated lymphocytes during the menstrual cycle in humans. AB - CD56+ CD16- granulated lymphocytes, termed endometrial granulated lymphocytes (eGLs), have been suggested to play a role in the maintenance of human pregnancy, although their in vivo function in both pregnant and nonpregnant endometrium remains unknown. The present study compared the cytotoxic activity of CD56+ CD16- eGLs (> 98% purity) positively selected from early and late proliferative-phase, early and late secretory-phase, and menstrual-phase endometrium with that of CD56+ CD16- eGLs purified from first-trimester decidua and CD56+ predominantly CD16+ cells from peripheral blood. From the late proliferative phase onwards, the major histocompatibility complex (MHC)-nonrestricted cytotoxic activity of eGLs was comparable between phases of the menstrual cycle. In contrast, eGLs from early proliferative-phase endometrium displayed significantly lower cytotoxic activity. With the exception of eGLs purified from early proliferative-phase endometrium, the cytotoxic activity of CD56+ CD16- eGLs purified from nonpregnant endometrium was comparable to that of CD56+ CD16- eGLs in decidua and CD56+ predominantly CD16+ cells from peripheral blood. No endogenous lymphokine activated killer cell activity was detected in eGLs from endometrium or decidua. The present study using highly purified eGLs demonstrates that, with the exception of early proliferative-phase samples, CD56+ CD16- eGLs from nonpregnant endometrium and early pregnancy decidua have cytotoxic activity comparable to that of "classical" natural killer cells from peripheral blood. PMID- 9369191 TI - Expression cloning of a rat testicular transcript abundant in germ cells, which contains two leucine zipper motifs. AB - The aim of the present study was to identify specific, novel germ cell markers that could be used to monitor normal and abnormal spermatogenesis. Of several cloned cDNAs isolated from an adult rat testis cDNA library using an expression screening strategy, clone 813B4 (700 base pairs) hybridized exclusively to three mRNA transcripts in samples isolated from rat testes on and after Day 21 of life and to epididymides from some, but not all, adult rats. After further screening, two identical clones encoding a 2.2-kilobase cDNA (KTT4) were isolated and found to contain an open reading frame of 578 amino acids including two leucine zipper motifs. On Northern blots, KTT4 mRNA was abundant in samples from round spermatids, and homologous mRNAs were present in testes from mice and marmosets. A zoo blot revealed that the KTT4 gene is conserved in humans, monkeys, mice, dogs, and cattle. On sections of rat testes, KTT4 mRNA was first detectable in pachytene spermatocytes at stage VII and thereafter was abundant in round and elongating spermatids until step 15. Expression of KTT4 was not altered by ethane dimethane sulphonate-induced androgen withdrawal, but in rats treated 14 days previously with methoxyacetic acid, a marked reduction in KTT4 was noted associated with the depletion of round spermatids. In conclusion, the present study identified a conserved gene expressed in meiotic and post-meiotic germ cells; database searches have shown it to be homologous to recently published sequences for an outer dense fiber protein of the sperm tail (Odf2/Odf84). PMID- 9369192 TI - Chronically elevated luteinizing hormone depletes primordial follicles in the mouse ovary. AB - A few years before reproductive senescence, primordial follicles are depleted from the ovary at a dramatically accelerated rate. It has been proposed that this depletion is due to transient increases in gonadotropin levels. To test this hypothesis, we used mice that produce chronically elevated levels of serum LH via expression of an LHbeta subunit transgene. Ovaries were collected from transgenic and control mice, and complete serial sections were prepared for histological examination. Each section was scanned for morphological abnormalities, and every fifth section was sampled to estimate the total number of primordial, primary, and large preantral follicles per ovary. Until 3 wk postpartum, ovaries from transgenic and control mice were morphologically similar. By 5 wk, control ovaries contained many healthy primordial, primary, and large preantral follicles as well as atretic follicles. Transgenic ovaries contained blood-filled cysts, misshapen granulosa cells, luteinized cells, and approximately 45% fewer primordial follicles than controls. By 3 mo, transgenic ovaries had about 68% fewer primordial follicles and 53% fewer primary follicles than controls. These results suggest that, in addition to having profound effects on growing follicles, chronically elevated LH levels deplete the primordial follicle pool and thus may hasten the onset of reproductive senescence. PMID- 9369193 TI - Salmonid follicle-stimulating hormone (GtH I) mediates vitellogenic development of oocytes in the rainbow trout, Oncorhynchus mykiss. AB - Rainbow trout (Oncorhynchus mykiss) were subjected to unilateral ovariectomy (ULO) during early vitellogenesis to examine the endocrine responses mediating the recruitment and growth of oocytes in the secondary (vitellogenic) growth phase. ULO induced recruitment of a second population of primary oocytes into the vitellogenic growth phase that then grew at a faster rate than oocytes in the control fish. Seven days post-ULO, the concentration of plasma salmonid FSH (sFSH = GtH I) was significantly higher than in controls and was elevated for at least 54 days. Maximal concentrations of sFSH in ULO fish (Day 21 post-ULO) were twice (10 ng/ml) those in controls. The data show that sFSH plays a primary role in mediating vitellogenic development. After ULO, plasma concentrations of estradiol 17beta were significantly lower than in controls up until 21 days post-ULO. Thereafter, plasma concentrations of estradiol-17beta did not differ from those in controls. The changes in concentrations of plasma estradiol-17beta and sFSH in the ULO fish demonstrated that the secretion of sFSH is probably not controlled by negative feedback of estradiol-17beta alone; in fish, as in mammals, it is likely that intragonadal autocrine/paracrine factors, such as inhibin and activin, also participate in the regulation of sFSH secretion. Plasma concentrations of testosterone did not appear to differ between the control and ULO fish. The responses in the production of estradiol-17beta and testosterone indicate that the dynamics of sex steroid synthesis in ovarian follicles in ULO fish was different than in the ovaries of control fish. PMID- 9369194 TI - Calcium, calcium release receptors, and meiotic resumption in bovine oocytes. AB - During maturation, mammalian oocytes undergo a series of changes that prepare them for fertilization. These events are regulated by kinases, most notably histone H1 and mitogen-activated protein kinase. Intracellular calcium ([Ca2+]i) oscillations participate in oocyte signaling, and it has been postulated that they play a role in oocyte maturation. In these studies we investigated the association of Ca2+, Ca2+ channels, and activation of kinases in in vitro maturating bovine oocytes. BAPTA-AM, a Ca2+ chelator, inhibited oocyte maturation and delayed activation of kinases, although spontaneous [Ca2+]i rises were not observed in control oocytes loaded with fura-2, a Ca2+ indicator. The ability of the 1,4,5-inositol trisphosphate receptor (InsP3R) to release Ca2+, monitored after the addition of thimerosal and myo-inositol 1,4,5-trisphosphate (InsP3), increased as maturation progressed. This may be associated with a similar increase, monitored by Western blotting, in the density of the type I InsP3R isoform during oocyte maturation. Injection of heparin, an InsP3R antagonist, blocked oocyte maturation and activation of kinases. The density of the ryanodine receptor, another Ca2+ channel, may be 30- to 100-fold lower than that of the InsP3R in bovine oocytes. Thus, our results demonstrate that [Ca2+]i participates in the progression of meiosis and that the InsP3R may be responsible for the majority of Ca2+ release during maturation and fertilization. PMID- 9369195 TI - Ontogeny of elongation and gene expression in the early developing porcine conceptus. AB - Early porcine conceptus development is characterized by rapid trophoblastic elongation between Days 11 and 12 of pregnancy, a period of embryonic loss in the pig. Growth factors and steroids secreted by the conceptus and uterus, as well as ligand receptors produced by the conceptus, are thought to regulate trophoblastic elongation. Therefore, the objectives of this study were to characterize conceptus gene expression for the steroidogenic enzymes 17alpha-hydroxylase and aromatase and the mesodermal marker brachyury, as well as the expression of receptors for fibronectin (integrin beta-1), progesterone, estrogen, oxytocin, prostaglandin F2alpha, and leukemia inhibitory factor (LIF), prior to and during trophoblastic elongation. Total RNA was extracted from individual conceptuses from Day 10 to Day 12 of pregnancy. Gene expression was determined by reverse transcription polymerase chain reaction on conceptuses having 2- to 4-, 5-, 6-, 7 , 8-, 9-, and 10- to 12-mm spherical, 13- to 25-mm tubular, and > 100-mm filamentous morphologies. There was a stage of development effect on both 17alpha hydroxylase (p < 0.001) and aromatase (p < 0.003) gene expression. Initial 17alpha-hydroxylase gene expression was detected in early spherical conceptuses (2-4 mm), increasing abruptly through to 7-mm conceptuses. Aromatase gene expression increased dramatically in 6- to 7-mm conceptuses, with increased expression throughout development. Gene expression for LIF receptor (LIFR) (p < 0.02) was similar to that for 17alpha-hydroxylase, while brachyury gene expression began in 6-mm conceptuses and increased (p < 0.001) throughout development. Integrin beta-1 was expressed at all stages of development. Conceptus gene expression was not detected for progesterone, estrogen, oxytocin, and prostaglandin F2alpha receptors. Prior to elongation, dynamic changes in gene expression are occurring that appear to be associated with estrogen production and preparation of the conceptuses for elongation. LIFR expression is highly associated with steroidogenic enzyme production with an initial peak preceding rapid trophoblastic elongation, suggesting that LIF may be involved in early conceptus development in the pig. PMID- 9369196 TI - Protection against oxidative damage of erythrocyte membrane by the flavonoid quercetin and its relation to iron chelating activity. AB - Incubation of glutathione (GSH) depleted mouse erythrocytes with the oxidants phenylhydrazine, acrolein, divicine and isouramil resulted in the release of free iron and in lipid peroxidation and hemolysis. The addition of the flavonoid quercetin, which chelates iron and penetrates erythrocytes, resulted in remarkable protection against lipid peroxidation and hemolysis. The protection seems to be due to intracellular chelation of iron, since a semi-stoichiometric ratio between released iron and the amount of quercetin necessary to prevent lipid peroxidation and hemolysis was found. Incubation of GSH depleted human erythrocytes with divicine and isouramil did not induce lipid peroxidation and hemolysis in spite of a substantial release of iron. However, divicine and isouramil produced alterations of membrane proteins, such as spectrin and band 3, as well as formation of senescent cell antigen. The addition of quercetin prevented these alterations. PMID- 9369197 TI - 1H NMR and fluorescence studies of the complexation of DMPG by wheat non-specific lipid transfer protein. Global fold of the complex. AB - Plant non-specific lipid transfer proteins (LTPs) are proteins which transfer lipids between membranes in vitro and are believed to be involved in the transport of cutin monomers to the cuticle layer in vivo or in the plant defence against phytopathogens. The complexation of DMPG, a diacyl phospholipid, by wheat ns-LTP, a protein extracted from wheat seeds, was followed by 1H NMR and fluorescence spectroscopy. The global fold of the protein was calculated using the DIANA software package from a list of 968 distance constraints. The internal cavity volume, a feature common to all known ns-LTP structures, was estimated to be 750 A3 using the 'CAVITE' program. This model of the complex was obtained by inserting a lipid molecule in the cavity and was energy minimized. The study showed that the protein fold described for the free form was only weakly affected by the insertion of the bulky lipid. Observation of some intermolecular NOEs between the protein and the lipid glycerol moiety revealed that the cavity entrance was located between residues His35 and Arg44. The resulting solution structure was compared to the crystal structure of the maize ns-LTP/palmitate complex. PMID- 9369198 TI - The different inhibitory domains of the Oct-2 transcription factor have distinct functional activities. AB - The Oct-2 POU family transcription factor contains three distinct regions whose deletion reduces its ability to inhibit transcription via its octamer binding site. Here we show that only one of these inhibitory domains is capable of also inhibiting the activity of activating molecules bound at adjacent sites upstream of a TATA box-containing promoter whereas the other two regions are inactive in this assay. None of the three regions is able to achieve this effect when located upstream of the same promoter containing an initiator motif. The mechanisms of action of these domains and their role in the functioning of the Oct-2 factor are discussed. PMID- 9369199 TI - An estrogen inducible 104 kDa chaperone glycoprotein binds ferric iron containing proteins: a possible role in intracellular iron trafficking. AB - We have previously described an estrogen inducible, intracellular, homodimeric membrane glycoprotein (subunit Mr 104 kDa) which is structurally related to 'chaperone' proteins (Poola, I. and Kiang J.G., J. Biol. Chem. 269 (1994) 21762 21769). In this report we describe a novel finding that the 104 kDa chaperone protein exhibits affinity for iron containing proteins such as transferrins from several species, human lactoferrin and microbial ferric binding protein (FBP). A single ferric ion in the above proteins appears to be sufficient for binding. It also binds to immobilized ferritin. However, it does not exhibit any affinity for apotransferrins, apolactoferrin, apoferritin and apoFBP. This is the first report of a chaperone protein that exhibits affinity for iron containing proteins. PMID- 9369200 TI - Cellulysin from the plant parasitic fungus Trichoderma viride elicits volatile biosynthesis in higher plants via the octadecanoid signalling cascade. AB - Cellulysin, a crude cellulase from the plant parasitic fungus Trichoderma viride, induces the biosynthesis of volatiles in higher plants (Nicotiana plumbaginifolia, Phaseolus lunatus, and Zea mays) when applied to cut petioles by the transpiration stream. The pattern of the emitted volatiles largely resembles that from a herbivore damage or treatment of the plants with jasmonic acid (JA) indicating that cellulysin acts via activation of the octadecanoid signalling pathway. The treatment with cellulysin raises the level of endogenous JA after 30 min and is followed by a transient emission of ethylene after 2-3 h. Volatile production becomes significant after 12-24 h. Inhibitors of the JA pathway effectively block the cellulysin-dependent volatile biosynthesis. PMID- 9369201 TI - Phosphorylation regulates the microtubule-destabilizing activity of stathmin and its interaction with tubulin. AB - Stathmin is a regulator of microtubule dynamics which undergoes extensive phosphorylation during the cell cycle as well as in response to various extracellular factors. Four serine residues are targets for protein kinases: Ser 25 and Ser-38 for proline-directed kinases such as mitogen-activated protein kinase and cyclin-dependent protein kinase, and Ser-16 and Ser-63 for cAMP dependent protein kinase. We studied the effect of phosphorylation on the microtubule-destabilizing activity of stathmin and on its interaction with tubulin in vitro. We show that triple phosphorylation on Ser-16, Ser-25, and Ser 38 efficiently inhibits its activity and prevents its binding to tubulin. PMID- 9369202 TI - Conversion of dihydroceramide to ceramide occurs at the cytosolic face of the endoplasmic reticulum. AB - Dihydroceramide desaturase is responsible for the introduction of the 4,5-trans double bond into ceramide. Here, we describe the localization of this enzyme in the endoplasmic reticulum (ER) using ER- and Golgi-enriched fractions from rat liver. Furthermore, enzyme topology was studied. Mild proteolysis of ER-derived vesicles under conditions which assure membrane integrity (latency of mannose 6 phosphatase was at least 91%) resulted in an up to 90% inactivation of dihydroceramide desaturase activity. This indicates a cytosolic orientation of dihydroceramide desaturase activity in the ER membrane. PMID- 9369204 TI - Elevation of apolipoprotein E in the CSF of cattle affected by BSE. AB - The cerebrospinal fluid (CSF) of patients suffering from Creutzfeldt-Jakob disease (CJD) display two unique polypeptide chains by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). In the absence of a well-defined ante-mortem diagnostic test for bovine spongiform encephalopathy (BSE), spinal fluid samples of eight normal cows and eight cows known to carry BSE by post mortem histological analysis were investigated to verify if equivalent polypeptides were present. Proteins with similar migration to human CJD polypeptides were not detected. But surprisingly, a cluster of polypeptide spots that was faint or not detected in normal bovine CSF samples was found to be elevated or massively increased in BSE CSF samples (more than 10-fold increase). These elevated polypeptide chains were identified as apolipoprotein E. PMID- 9369203 TI - Sequence analysis of a 24-kb contiguous genomic region at the Arabidopsis thaliana PFL locus on chromosome 1. AB - As part of the European Union program of European Scientist Sequencing Arabidopsis (ESSA), the DNA sequence of a 24.053-bp insert of cosmid clone CC17J13 was determined. The cosmid is located on chromosome 1 at the PFL locus (position 30 cM). Analysis of the sequence and comparison to public databases predicts seven genes in this area, thus approximately one gene every 3.3 kb. Three cDNAs corresponding to genes in this region were also sequenced. The homologies and/or possible functions of the (putative) genes are discussed. Proteins encoded by genes in this region include a polyadenylate-binding protein (PAB-3) and a GTP-binding protein (Rab7) as well as a novel protein, possibly involved in double-stranded RNA unwinding and apoptosis. Intriguingly, the gene encoding the PAB-3 protein, which is very specifically expressed, is flanked by putative matrix attachment regions. PMID- 9369205 TI - The Su(Ste) repeat in the Y chromosome and betaCK2tes gene encode predicted isoforms of regulatory beta-subunit of protein kinase CK2 in Drosophila melanogaster. AB - We report an exon-intron structure of the Su(Ste) repeat capable of encoding an isoform of the beta-subunit of protein kinase CK2. The predicted Su(Ste) gene product contains a drastically changed amino acid sequence of the N-terminal fragment as compared to the earlier described bCK2tes gene considered to be an ancestor of the Su(Ste) repeats. The following peculiarities of molecular divergence of the Su(Ste) and betaCK2tes genes are revealed: damages of the autophosphorylation site; usage of an alternative splicing site instead of a damaged one; conservation of the zinc finger domain in spite of local ORF alterations. PMID- 9369206 TI - Titration kinetics of Asp-85 in bacteriorhodopsin: exclusion of the retinal pocket as the color-controlling cation binding site. AB - The spectrum (the purple blue transition) and function of the light-driven proton pump bacteriorhodopsin are determined by the state of protonation of the Asp-85 residue located in the vicinity of the retinal chromophore. The titration of Asp 85 is controlled by the binding/unbinding of one or two divalent metal cations (Ca2+ or Mg2+). The location of such metal binding site(s) is approached by studying the kinetics of the cation-induced titration of Asp-85 using metal ions and large molecular cations, such as quaternary ammonium ions, R4N+ (R = Et, Pr, a divalent 'bolaform ion' [Et3N+-(CH2)4-N+Et3] and the 1:3 molecular complex formed between Fe2+ and 1,10-phenanthroline (OP). The basic multi-component kinetic features of the titration, extending from 10(-2) to 10(4) s, are unaffected by the charge and size of the cation. This indicates that cation binding to bR triggers the blue --> purple titration in a fast step, which is not rate-determining. In view of the size of the cations involved, these observations indicate that the cation binding site is in an exposed location on, or close to, the membrane surface. This excludes previous models, which placed the color controlling Ca2+ ion in the retinal binding pocket. PMID- 9369207 TI - Spontaneous spectral changes of the reduced cytochrome bd. AB - Reduction of the membrane-bound cytochrome bd from Bacillus subtilis, Escherichia coli and Azotobacter vinelandii as well as of the purified enzyme from E. coli was followed by secondary absorption changes on a time scale of tens of minutes. The difference absorption spectra of these changes resembled those induced by CO binding with heme d2+ indicating interaction of the heme with an endogenous pi acceptor ligand. The spontaneous spectral changes were prevented and reversed by CO binding with the reduced cytochrome bd. Bonding of heme d iron to an endogenous protein ligand at the sixth axial position upon reduction is proposed and several possible mechanisms of such a process are considered. PMID- 9369208 TI - 2,7-Dihydrodichlorofluorescein diacetate as a fluorescent marker for peroxynitrite formation. AB - Reactive oxygen species (ROS) have been implicated as an important causative factor in cell damage, including apoptosis and necrosis. Their proposed actions comprise lipid peroxidation, DNA damage, destruction of the mitochondrial respiratory chain and protein modifications. Recent experiments underline the importance of peroxynitrite, the reaction product of the two potent reactive species nitric oxide and superoxide. Several fluorogenic compounds have been used in order to determine ROS formation in living cells. Besides dihydrorhodamine-123 (DHR-123), at present mostly applied to monitor peroxynitrite, 2,7 dihydrodichlorofluorescein (DCF-H) is used for detection of hydrogen peroxide and nitric oxide. We employed a cell free approach to evaluate the specificity and sensitivity of DCF-H to various oxidizing compounds. Our studies imply that DCF-H is much more sensitive to peroxynitrite oxidation than any other compound tested. In order to study peroxynitrite generation within individual cells, primary glial cultures loaded with DCF-H were monitored with a laser scanning microscope. Microglia, stimulated to simultaneously produce the peroxynitrite precursors nitric oxide and superoxide, displayed the greatest increase in DCF fluorescence, whereas microglia producing either nitric oxide or superoxide alone showed a relatively small increase in DCF fluorescence. In conclusion, DCF-H was demonstrated to be an excellent peroxynitrite marker with the potential to detect peroxynitrite formation in living cells. PMID- 9369209 TI - Nitrogen source-dependent expression of a 126 kDa protein in the plasma membrane of the cyanobacterium Synechococcus PCC 7942. AB - The expression of a 126 kDa protein in the cytoplasmic membrane of Synechococcus PCC 7942 is shown to be dependent on the nitrogen source. It is absent in ammonium-grown cells and its quantity is inversely related to the concentration of nitrate or nitrite in the growth medium. Addition of ammonium-grown cells to a medium containing nitrate or L-methionine-DL-sulfoximine results in the expression of this protein. It is present in the plasmalemma of the Synechococcus NC3 mutant (nrtC gene deleted) and absent in the NA3 mutant (nrtABCD genes deleted). These results may suggest involvement of the 126 kDa protein in nitrate transport through Synechococcus cytoplasmic membrane. PMID- 9369210 TI - Resistance to tumor necrosis factor (TNF) cytotoxicity by autocrine TNF production is independent of intracellular signaling pathways. AB - We previously showed that autocrine tumor necrosis factor (TNF) production in the TNF-sensitive L929sA fibrosarcoma cell line induced TNF resistance, which is correlated with downmodulation of both TNF receptors on the cell surface. We now analyzed whether autocrine TNF production also interfered with intracellular TNF signaling pathways. The L929sA-CAT-R55i cell line, in which cell death can be induced by controlled cytoplasmic expression of a trimeric fusion protein between chloramphenicol acetyltransferase and the intracellular domain of TNF-R55 (CAT R55i), was supertransfected with the murine TNF gene. Expression of the latter conferred resistance to cell death induced by exogenous TNF, while cytotoxicity induced by CAT-R55i was not impaired. This demonstrates that autocrine TNF did not induce intracellular mechanisms that block TNF signaling leading to cell death. Thus the induction of TNF resistance via autocrine TNF production in L929sA cells is solely due to downmodulation of TNF receptors on the cell surface. PMID- 9369211 TI - Is the mammalian porin channel, VDAC, a perfect cylinder in the high conductance state? AB - The mammalian porin channel (VDAC, porin-31BM) was reconstituted in planar lipid bilayers under voltage clamp conditions. The radii of both entrances of the channel were examined using a method that consisted in filling the channel with different non-electrolytes through its cis or trans entrances while recording single channel conductances. As a result it was found that the geometry of channels formed by porin-31BM could not be approximated by a perfectly cylindrical pore. In fact there is an asymmetry in the geometry of the channel: the diameters of the cis and trans entrances were estimated to be approximately 2 nm and approximately 4 nm respectively. PMID- 9369212 TI - The fungal elicitor cryptogein is a sterol carrier protein. AB - Cryptogein is a protein secreted by the phytopathogenic pseudo-fungus, Phytophthora cryptogea. It is a basic 10 kDa hydrophilic protein having a hydrophobic pocket and three disulfide bridges. These common features with sterol carrier proteins led us to investigate its possible sterol transfer activity using the fluorescent sterol, dehydroergosterol. The results show that cryptogein has one binding site with strong affinity for dehydroergosterol. Moreover, this protein catalyzes the transfer of sterols between phospholipidic artificial membranes. This is the first evidence for the existence of an extracellular sterol carrier protein and for a molecular activity of cryptogein. This property should contribute to an understanding of the role of cryptogein in plant microorganism interactions. PMID- 9369213 TI - Epitope mapping by screening of phage display libraries of a monoclonal antibody directed against the receptor binding domain of human alpha2-macroglobulin. AB - The human proteinase inhibitor, alpha2-macroglobulin (a2-M), inhibits a large number of proteinases. Alpha2-M-proteinase complexes are rapidly cleared from the circulation by binding to a cellular receptor (alpha2-M-R/LRP) via the receptor binding domain (RBD) which is made up of a 20 kDa C-terminal stretch of the 180 kDa monomer of the inhibitor. A monoclonal antibody (mab alpha-1) has been described which reacts with the receptor-recognizable form of the inhibitor, the so called transformed alpha2-M (a2-Mt). By screening of a phage display library an epitope in the RBD of the inhibitor was identified that reacts with mab alpha 1. Out of 25 phage clones a heptapeptide sequence (S-x1-x2-D-x3-x4-K) was obtained containing identical amino acids in three positions. A consensus peptide (S-R-S-D-P-P-K) was synthesized and found to displace alpha2-Mt from binding to mab alpha-1 and to receptor. The specificity of competition was demonstrated by a reversed peptide and a control antibody. By structural comparison it was found that the consensus heptapeptide mimics a discontinuous conformationally constrained epitope present in the RBD of the inhibitor. This is the first report describing the detection of discontinuous epitopes by phage display using a short linear peptide. PMID- 9369214 TI - The disulphide bond pattern of bitistatin, a disintegrin isolated from the venom of the viper Bitis arietans. AB - The disulphide bond pattern of the long disintegrin bitistatin (83 amino acids, 14 cysteines) was established using structural information gathered by amino acid analysis, N-terminal sequencing, and molecular mass determination of fragments isolated by reversed-phase HPLC after polypeptide degradation with trypsin and oxalic acid. A computer program was used to calculate all possible combinations of disulphide-bonded peptides matching the mass spectrometric data, and the output was filtered using compositional and sequence data. Disulphide bonds between cysteines 16-34, 18-29, 28-51, 42-48, 47-72, and 60-79 are conserved in medium-long disintegrins flavoridin and kistrin (70 amino acids, 12 cysteines), and the two cysteine residues at positions 5 and 24 found in bitistatin but not in other disintegrin molecules are disulphide-bridged. This linkage creates an extra, large loop, which, depending on whether the NMR structure of flavoridin or kistrin is used for modelling the structure of bitistatin, lies opposite or nearly parallel, respectively, to the biologically active RGD-containing loop. PMID- 9369215 TI - Definitive chemical evidence for the constitutive ability of Candida albicans serotype A strains to synthesize beta-1,2 linked oligomannosides containing up to 14 mannose residues. AB - We have previously reported the presence of phosphate bound beta-1,2 linked oligomannosides with unusually high degrees of polymerization (DP > 7) in the mannan of Candida albicans strain VW32. To confirm this observation, we have prepared these oligomannosides from the mannan of C. albicans strain NIH A 207. Gel filtration chromatography and TLC analysis revealed DP up to 14. For both strains, NMR analysis confirmed the exclusive presence of beta-1,2 linkages in the pools of oligomannosides with a DP higher than 6 which presented an average DP of 10.6 (VW32) and 10.4 (NIH A 207). These results are important to consider in relation with the ability of these C. albicans derived oligomannosides to trigger TNFalpha synthesis according to their DP. PMID- 9369216 TI - c-di-GMP-binding protein, a new factor regulating cellulose synthesis in Acetobacter xylinum. AB - A protein which specifically binds cyclic diguanylic acid (c-di-GMP), the reversible allosteric activator of the membrane-bound cellulose synthase system of Acetobacter xylinum, has been identified in membrane preparations of this organism. c-di-GMP binding is of high affinity (KD 20 nM), saturable and reversible. The equilibrium of the reaction is markedly and specifically shifted towards the binding direction by K+. The c-di-GMP binding protein, structurally associated with the cellulose synthase, appears to play a major role in modulating the intracellular concentration of free c-di-GMP and thus may constitute an essential factor in regulating cellulose synthesis in vivo. PMID- 9369217 TI - Classification of 'activation' antibodies against integrin beta1 chain. AB - We compared the effects of two anti-beta1 integrin activating antibodies, TS2/16 and AG89, on K562 cell adhesion to fibronectin. Though both antibodies effectively induced cell adhesion, the EC50 for AG89 was more than 200-fold higher than that for TS2/16. Scatchard analysis of the data from [125I]Fab fragment binding to the cells revealed that the TS2/16 epitope is exposed constitutively on all the beta1 integrin molecules, while only 3% of the beta1 integrins on resting K562 cells bear the AG89 epitope. Calculation of the actual number of each antibody bound to the cell during the cell adhesion assay revealed that induction of cell adhesion can be accomplished by binding much fewer AG89 molecules compared to TS2/16. Thus, AG89 and TS2/16 represent distinct classes of anti-integrin activating antibodies that show completely different binding characteristics as well as different activation effects on the integrin molecule upon binding. PMID- 9369218 TI - Role of the N-terminus in the structure and stability of chicken annexin V. AB - The role of the short N-terminal region of chicken annexin V in the maintenance of the protein structure and its influence in the conformation of the calcium binding regions was analyzed. The N-terminal domain is not essential for protein folding, wild-type and dnt-annexin V showing almost identical secondary structures. However, the partial truncation of the N-terminus significantly decreases the melting temperature of the protein and induces the partial exposure of Trp187 which is normally located in a hydrophobic pocket of the calcium binding region of domain 3 of annexin V in the Ca2+-free form. PMID- 9369219 TI - Did cyclodextrin glycosyltransferases evolve from alpha-amylases? AB - The hydrolytic enzymes, alpha-amylases, and the cyclodextrin glycosyltransferases (CGTases) are key enzymes in the depolymerization of starch. These two groups of enzymes are evolutionarily related. We propose that the transferase activity is likely to have evolved from an ancestral hydrolase. Sequence analysis provides support for this hypothesis. Consequently, we have conducted an experimental study to test the possible adaptive value for evolving a CGTase. We found that when an alpha-amylase and a CGTase are combined more glucose is generated from starch than would be expected from the independent action of either of these enzymes. Thus, we propose that the biological role of CGTases is to work in concert with alpha-amylases for the efficient saccharification of starch. This observation can be useful in industrial processes aimed at producing syrups with high contents of glucose or maltose. PMID- 9369220 TI - Effect of temperature on the role of Hsp104 and trehalose in barotolerance of Saccharomyces cerevisiae. AB - We have studied the effect of temperature on the contribution of Hsp104 and trehalose to barotolerance using mutants deficient in Hsp104 and trehalose synthesis. When compared with a corresponding wild type strain, mutants of Hsp104 did not show temperature dependent barotolerance when the incubation temperature during the hydrostatic pressure treatment was increased. However, a mutant deficient in trehalose synthesis showed features similar to a wild type strain. Furthermore, the Hsp104 level was low in the insoluble fraction of the wild type strain after pressure treatment at 35 degrees C but not at 4 degrees C, and the protein profiles in the insoluble fraction were different between 35 degrees C and 4 degrees C. In contrast to the Hsp104 deficient mutants, the protein profile of the wild type after pressure treatment at 35 degrees C favors the role of Hsp104 as a disaggregator of proteins during hydrostatic pressure stress. These results suggest that the role of Hsp104 in barotolerance is temperature dependent in contrast to trehalose. PMID- 9369221 TI - Molecular analysis of the interaction between HPV type 16 E6 and human E6 associated protein. AB - The complex formed between the human papillomavirus type 16 E6 protein and human E6-associated protein, which combine to ubiquitylate and degrade p53, has been studied by chemical crosslinking. Analysis of the interactions of proteins purified from Escherichia coli as well as proteins expressed in insect cells indicates that, while E6 has the capacity to form dimers, E6 and E6-associated protein interact as two monomers to form a heterologous dimer. PMID- 9369222 TI - Insertion of a SNS-specific tetrapeptide in S3-S4 linker of D4 accelerates recovery from inactivation of skeletal muscle voltage-gated Na channel mu1 in HEK293 cells. AB - Na channel subunits alphaSNS (PN3) and alpha mu1(SkM1) produce slowly inactivating/TTX-resistant and rapidly inactivating/TTX-sensitive currents, respectively. AlphaSNS (PN3) current recovers from inactivation (reprimes) rapidly. Sequence alignment identified the tetrapeptide SLEN, in the S3-S4 linker of D4, as alphaSNS-specific. To determine whether SLEN endows Na channels with slow kinetics and/or rapid repriming, we analyzed the transient Na current produced by a chimera mu1SLEN in HEK293 cells. Neither kinetics nor voltage dependence of activation and inactivation was affected. However, repriming was twice as fast as in the wild type at -100 mV. This suggests that SLEN may contribute to the rapid repriming of TTX-resistant Na current. PMID- 9369223 TI - High protonic potential actuates a mechanism of production of reactive oxygen species in mitochondria. AB - Formation of H2O2 has been studied in rat heart mitochondria, pretreated with H2O2 and aminotriazole to lower their antioxidant capacity. It is shown that the rate of H2O2 formation by mitochondria oxidizing 6 mM succinate is inhibited by a protonophorous uncoupler, ADP and phosphate, malonate, rotenone and myxothiazol, and is stimulated by antimycin A. The effect of ADP is abolished by carboxyatractylate and oligomycin. Addition of uncoupler after rotenone induces further inhibition of H2O2 production. Inhibition of H2O2 formation by uncoupler, malonate and ADP+Pi is shown to be proportional to the delta psi decrease by these compounds. A threshold delta psi value is found, above which a very strong increase in H2O2 production takes place. This threshold slightly exceeds the state 3 delta psi level. The data obtained are in line with the concept [Skulachev, V.P., Q. Rev. Biophys. 29 (1996), 169-2021 that a high proton motive force in state 4 is potentially dangerous for the cell due to an increase in the probability of superoxide formation. PMID- 9369224 TI - Thyroid hormone-induced expression of the ADP/ATP carrier and its effect on fatty acid-induced uncoupling of oxidative phosphorylation. AB - Liver mitochondria from rats made hypothyroid by administration of 2-mercapto-1 methylimidazole were less sensitive to the uncoupling effect of myristic acid, as measured by the increase of resting state respiration, than mitochondria from euthyroid animals, whereas subsequent administration to the animals of triiodothyronine ('hyperthyroidism') resulted in an increased uncoupling action of myristate. 'Hyperthyroidism' also resulted in doubling of the carboxyatractyloside-sensitive portion of the myristate-stimulated respiration. Parallel to this was a twofold increase of the mitochondrial content of the ADP/ATP carrier protein and an over threefold increase of its activity. The uncoupling effect of phytanic acid was less sensitive to carboxyatractyloside and was increased in the hyperthyroid state to a smaller extent than in the case of myristate. These results provide further support to the thesis [Skulachev, V.P., FEBS Lett. 294 (1991) 158-162] that the ADP/ATP carrier is involved in the mechanism of the uncoupling effect of long-chain fatty acids. PMID- 9369225 TI - DNA-hydrolyzing activity of the light chain of IgG antibodies from milk of healthy human mothers. AB - Various catalytically active antibodies or abzymes have been detected recently in the sera of patients with several autoimmune pathologies, where their presence is most probably associated with autoimmunization. Normal humans are generally considered to have no abzymes, since no obvious immunizing factors are present. Recently we have shown that IgG (its Fab and F(ab)2 fragments) from the milk of normal humans possesses DNase activity. Here we demonstrate for the first time that the light chain of IgG catalyzes the reaction of DNA hydrolysis. These findings speak in favor of the generation of abzymes in the tissue of healthy mothers, and since a mother's breast milk protects her infant from infections until the immune system is developed, they raise the possibility that these abzymes may contribute to this protective role. PMID- 9369226 TI - Insulin dependent tyrosine phosphorylation of the tyrosine internalisation motif of TGN38 creates a specific SH2 domain binding site. AB - Tyrosine-based motifs are involved in both protein targeting and, via SH2 domain binding, intracellular signalling. To date there has only been one example of such a motif acting as both an intracellular sorting signal and SH2 binding determinant, namely that of the T cell costimulation receptor, CTLA-4. We show that insulin stimulation of cultured rat hepatoma cells results in increased cell surface expression of TGN38. Furthermore, the cytosolic domain of TGN38 can be phosphorylated by the insulin receptor in vitro and tyrosine phosphorylated TGN38 can specifically bind to the SH2 domains of the spleen tyrosine kinase Syk. These data imply that tyrosine-based motifs may play a broader role than has previously been accepted and could help to integrate trafficking and signalling events. PMID- 9369227 TI - Identification of novel homologues of mouse importin alpha, the alpha subunit of the nuclear pore-targeting complex, and their tissue-specific expression. AB - Transport of karyophilic proteins into the nucleus is mediated by nuclear localization signals (NLSs) via a multistep process. The karyophiles are recognized by the importin alpha subunit in the cytoplasm to form a stable complex, termed the nuclear pore-targeting complex (PTAC). To date, three different mammalian alpha subunits (mSRP1/NPI-1, PTAC58/mPendulin/Rch1 and Qip1) have been identified. In this study, we report the identification of three additional mouse genes homologous to the known alpha subunits using RT-PCR methodology and show that the mouse alpha subunits can be classified into at least three subfamilies, alpha-P, alpha-Q and alpha-S families, each composed of closely related members (more than 80% amino acid sequence identity). These three subfamilies, however, have approximately 50% amino acid identity to one another. Northern blot analysis showed that all were differentially expressed in various mouse tissues. These results suggest that the function of these proteins may be controlled in a tissue-specific manner and that their combinatorial expression may play a role in differentiation and organogenesis. PMID- 9369228 TI - Interaction of SecB with soluble SecA. AB - The preprotein binding molecular chaperone SecB functions by preventing the premature folding of the preprotein in the cytosol, and targeting it to the peripheral subunit SecA of the translocase at the cytoplasmic membrane. The nature of the interaction of SecB with soluble SecA was studied by fluorescence anisotropy spectroscopy of Ru(bpy)2(dcbpy)-labeled SecA in the presence of increasing concentrations of SecB. A more than 50-fold difference in affinity for the cytosolic SecA compared to translocase associated SecA seems to prevent unproductive binding of SecB to the cytosolic SecA and stresses its targeting function. PMID- 9369229 TI - The betagamma subunits of heterotrimeric G proteins acquire detergent insolubility directly at the plasma membrane. AB - The subunits of heterotrimeric G proteins, G alpha and G betagamma, are found in association with detergent-resistant domains in most mammalian cell types, implicating such domains in G protein-coupled signaling. The pathway by which the betagamma complexes are targeted to these detergent-resistant domains was unaffected by the brefeldin A-imposed block on endoplasmic reticulum-to-Golgi transport. We have used subcellular fractionation and beta subunit-specific immunoprecipitation to localize the acquisition of detergent insolubility of newly synthesized betagamma complexes. The beta subunits cofractionate with plasma membranes, and acquire detergent insolubility coincident with arrival in the plasma membrane fractions. This association was not affected by phorbol 12 myristate 13-acetate-induced activation of Protein kinase C. PMID- 9369231 TI - A novel autophosphorylation mediated regulation of nitrite reductase in Candida utilis. AB - The assimilatory nitrite reductase catalyses the conversion of nitrite to ammonia. The enzyme from Candida utilis has been previously purified to homogeneity and shown to be a heterodimer consisting of 58 kDa and 66 kDa subunits. The enzyme has also been shown to be induced by nitrate and repressed by ammonium ions. The levels of nitrite reductase mRNA, its protein and the enzyme activity were modulated together indicating that the primary level of regulation of this enzyme existed at the transcriptional level. Here we report that the 58 kDa and 66 kDa subunits of the enzyme were differentially phosphorylated under the induced and repressed conditions, indicating a second level of regulation. The highly phosphorylated 66 kDa subunit was shown to be dephosphorylated by calf intestinal alkaline phosphatase. The enzymatic activity associated with the native enzyme also decreased due to the dephosphorylation. Each of the subunits could undergo autophosphorylation at serine/threonine residues as demonstrated by thin layer chromatography and recognition by antibodies to phosphoamino acids. The presence of similar phosphorylated subunits under in vivo conditions has also been demonstrated. A model has been proposed to explain the post-translational regulation of the enzyme. PMID- 9369230 TI - Disturbed progastrin processing in carboxypeptidase E-deficient fat mice. AB - The fat mouse strain exhibits a late-onset obesity syndrome associated with a mutation in the gene encoding carboxypeptidase E (CPE). Since CPE plays a central role in the biosynthesis of a number of regulatory peptides, including gastrin, we examined the biogenesis and processing of progastrin in fat/fat mice by measuring gastrin mRNA, carboxyamidated gastrin and its processing intermediates in the stomach. The tissue concentration of carboxyamidated (i.e. bioactive) gastrin was only slightly reduced (601 +/- 28 pmol/g in fat/fat mice vs. 715 +/- 43 pmol/g in wild-type controls). However, progastrin processing intermediates accumulated excessively with an 86-fold increase in the concentration of the CPE substrate, glycyl-arginine extended gastrin, and a seven-fold increase in the concentration of glycine-extended gastrin. Accordingly, the total progastrin product was doubled, as was the concentration of gastrin mRNA. Plasma concentrations of carboxyamidated gastrin were, however slightly reduced both in fasted fat/fat mice and postprandially. The results show that the CPE mutation diminishes the efficiency of progastrin processing, but gastrin synthesis is nevertheless increased to maintain an almost normal production of bioactive gastrins. By comparison with other neuroendocrine prohormones, progastrin processing in CPE-deficient mice is unique. Hence, the increase of glycine extended gastrin in combination with normal levels of carboxyamidated gastrin suggests that G-cells may have another biosynthetic pathway for gastrin. PMID- 9369232 TI - Evidence for lipid kinase activities in spinach chloroplast envelope membranes. AB - Three spinach chloroplast envelope membrane preparations (i.e. whole, outer and inner membranes) were incubated in the presence of [gamma-32P]ATP. After lipid extraction and separation by TLC, four main phosphorylated lipids were detected by autoradiography in whole envelope preparations. These phospholipids were identified by comparing their Rf with that of lipid markers and by a deacylation procedure. They were found to be phosphatidic acid (PA) and lyso-PA, L-alpha phosphatidyl-inositol 4-monophosphate (PIP) and lyso-PIP. These lipids were not equally distributed in the outer and inner envelope membranes. Chloroplast envelope membranes were verified not to be contaminated by plasma membranes. It is concluded that lipid kinase activities are associated with spinach chloroplast envelope membranes. PMID- 9369233 TI - Purification, biochemical properties and substrate specificity of a catechol 1,2 dioxygenase from a phenol degrading Acinetobacter radioresistens. AB - A catechol 1,2-dioxygenase (C1,2O) has been purified to homogeneity from Acinetobacter radioresistens grown on phenol as the sole carbon and energy source. The C1,2O appears to be a homodimer, with a molecular mass of 78,000 Da. At relatively high ionic strengths (0.5 M Na2SO4) subunit dissociation occurs and the monomeric unit (38,700 Da) is shown to be active. This phenomenon has never been observed before in dioxygenases. The purified C1,2O contains 0.96 iron(III) ions per unit and spectroscopic measurements suggest the presence of one high spin iron(III) ion in an environment characteristic of intradiol cleaving enzymes. The NH2-terminal amino acid sequence has been determined and compared to the primary structures of intradiol rings cleaving dioxygenases from other Acinetobacter strains revealing 45% homology with the benzoate-grown A. calcoaceticus ADP-1 and an identity of only one of the 20 amino acids sequenced for the phenol-grown A. calcoaceticus NCIB 8250. PMID- 9369234 TI - Limited photosynthetic electron flow but no CO2 fixation in Chlamydomonas mutants lacking photosystem I. AB - By measuring O2 and CO2 exchange in mutants of the green alga Chlamydomonas reinhardtii in which genes encoding the reaction center of photosystem I (psaA or psaB) have been deleted, we found that a photosystem II-dependent electron flow using O2 as the final acceptor can be sustained in the light. However, in contrast with recent reports using other Chlamydomonas mutants (B4 and F8), we show here that CO2 fixation does not occur in the absence of photosystem I. By deleting the psaA gene in both B4 and F8 strains, we conclude that the ability of these mutants to fix CO2 in the light is due to the presence of residual amounts of photosystem I. PMID- 9369235 TI - Induction of manganese superoxide dismutase by thyroid stimulating hormone in rat thyroid cells. AB - Alterations in the superoxide dismutase (SOD) content of thyroid tissues occurring in association with thyroid dysfunction have been reported. In this study, the Mn-SOD content was found to increase in thyroid tissues of rats administered thyroid stimulating hormone (TSH) and in thyrocytes cultured in medium supplemented with TSH. Furthermore, in the thyroid glands of rats whose serum TSH level was elevated by inhibiting the synthesis of T3 and T4 by 6-methyl 2-thiouracil, the Mn-SOD increased as the TSH concentration increased. In the cultured thyrocytes, the increase in Mn-SOD induced by TSH was inhibited by the C kinase inhibitor H7. These findings suggest the induction of Mn-SOD by TSH in thyroid cells and point to a role of C-kinase in this process, thereby indicating that a close relationship exists between the serum TSH level and the change in Mn SOD content in thyrocytes with thyroid dysfunction. PMID- 9369236 TI - Trifluoroethanol-induced conformational transition of hen egg-white lysozyme studied by small-angle X-ray scattering. AB - The trifluoroethanol (TFE)-induced conformational transition of hen lysozyme was studied with the combined use of far-UV circular dichroism (CD) and small-angle X ray scattering. At pH 2.0 and 20 degrees C, the addition of TFE to the native lysozyme induced a cooperative transition to an intermediate state with an increased helical content (TFE state). Small-angle X-ray scattering measurements indicated that the TFE state has a radius of gyration which is 20% larger than that of the native state and assumes a chain-like conformation with some remaining globularity. The TFE-induced transition curves obtained by CD and the small-angle X-ray scattering measurements agreed well, consistent with a two state transition mechanism. A singular value decomposition analysis of Kratky plots of the small-angle X-ray scattering profiles indicated that two basic scattering functions reproduce the observed spectra, further confirming the validity of a two-state approximation. PMID- 9369237 TI - Stoichiometry of 7-ethoxycoumarin metabolism by cytochrome P450 2B1 wild-type and five active-site mutants. AB - Recombinant P450 2B1 wild-type and the active-site mutants I114V, F206L, V363A, V363L, and G478S were purified and studied. The efficiency of coupling of reducing equivalents to 7-hydroxycoumarin formation was decreased for all the mutants except I114V. Uncoupling to H2O was increased for F206L, V363A, and G478S, decreased for V363L, and unchanged for I114V. Uncoupling to H2O2 was increased for V363L and decreased for I114V, F206L, and V363A. The findings from this study provide firm biochemical evidence that residues 206, 363, and 478 comprise part of the substrate binding site of P450 2B1. PMID- 9369238 TI - Modulation of cellular AP-1 DNA binding activity by heat shock proteins. AB - Recent studies have indicated that ubiquitously expressed molecular chaperones of the heat shock protein (Hsp) class may have an additional, nuclear, role in the regulation of gene expression. Experiments on cellular transcription factors derived from the rat adrenal gland have now shown that Hsps modulate in vitro DNA binding activity of the AP-1 factor. Both Hsc70 (p73) and Hsp70 (p72) were demonstrated to exert this effect through a mechanism that appears to be independent of both redox, and phosphorylation state. Further studies on the effect of Hsps on recombinant Fos/Jun protein binding activity indicated that the mechanism of action involves a selective attenuation of high affinity c-Fos:c-Jun binding as compared with c-Jun homodimer binding activity. Because cellular and physiological stress are associated with the induction of both AP-1 and Hsps it is apparent that Hsps may play a modulatory role in the regulation of AP-1 responsive genes. PMID- 9369239 TI - A model for the [C+-GxC]n triple helix derived from observation of the C+-GxC base triplet in a crystal structure. AB - A molecular modelling study on the [C+-GxC]n triple helix is reported. We have observed the C+-GxC base triplet in the crystal structure of an oligonucleotide drug complex, between the minor-groove drug netropsin and the decanucleotide d(CGCAATTGCG)2. The complex was crystallised at pH 7.0, but the crystal structure, at a resolution of 2.4 A, shows that a terminal cytosine has become protonated and participates in a parallel C+-GxC base triplet. The structure of this triplet and its associated sugar-phosphate backbones have been energy refined and then used to generate a triple helix. This has characteristics of the B-type family of DNA structures for two strands, with the third, the C+ strand, having backbone conformations closer to the A family. PMID- 9369240 TI - Stimulation of glyceraldehyde-3-phosphate dehydrogenase by oxyhemoglobin. AB - Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key glycolytic enzyme regulated by many diverse mechanisms. In this study we present evidence that GAPDH activity is stimulated in the presence of oxyhemoglobin (2.3-fold, P < 0.005). No stimulation was seen by myoglobin, and only slight stimulation (1.2 fold, not significant) by methemoglobin was observed. Such stimulation may have physiological significance as 1,3-bis-phosphoglycerate, the product of GAPDH, isomerises to 2,3-bis-phosphoglycerate, an allosteric effector that decreases the oxygen affinity of hemoglobin, thus providing a feedback loop. The results suggest that when assaying GAPDH activity in biological samples, hemoglobin content should be taken into account. PMID- 9369241 TI - Slight sequence variations of a common fold explain the substrate specificities of tRNA-guanine transglycosylases from the three kingdoms. AB - tRNA-guanine transglycosylases (TGTs) are the enzymes catalyzing the base exchange required for the synthesis of the modified bases derived from 7 deazaguanine in prokaryotic, archaebacterial, and eukaryotic tRNAs. Unlike the eukaryotic and archaebacterial enzymes, the prokaryotic TGTs have been clearly identified and highly characterized both biochemically and structurally. The recent occurrence in sequence databases of archaebacterial and eukaryotic proteins homologous to the prokaryotic TGTs reveals that all TGTs unexpectedly adopt a common fold. Observed sequence variations at the active site correlate well with their specificities for the various 7-deazaguanine derivatives and the total conservation of the catalytic residues strongly favors a common catalytic mechanism for all TGTs. PMID- 9369242 TI - Class 2 aldehyde dehydrogenase. Characterization of the hamster enzyme, sensitive to daidzin and conserved within the family of multiple forms. AB - Mitochondrial (class 2) hamster aldehyde dehydrogenase has been purified and characterized. Its primary structure has been determined and correlated with the tertiary structure recently established for this class from another species. The protein is found to represent a constant class within a complex family of multiple forms. Variable segments that occur in different species correlate with non-functional segments, in the same manner as in the case of the constant class of alcohol dehydrogenases (class III type) of another protein family, but distinct from the pattern of the corresponding variable enzymes. Hence, in both these protein families, overall variability and segment architectures behave similarly, with at least one 'constant' form in each case, class III in the case of alcohol dehydrogenases, and at least class 2 in the case of aldehyde dehydrogenases. PMID- 9369243 TI - How melatonin interacts with lipid bilayers: a study by fluorescence and ESR spectroscopies. AB - ESR spectra of spin labels placed at the membrane surface and at different depths of the bilayer core, and melatonin fluorescence in the presence of lipid vesicles, suggest an average shallow position for the hormone in the membrane. However, according to the melatonin ability to cross lipid bilayers, nitroxides placed deep in the bilayer were able to quench the melatonin fluorescence. Melatonin membrane partition coefficients were calculated for bilayers in different packing states, and similar and rather high values were found. The data presented here may be quite important to the understanding of melatonin physiological actions at the membrane level. PMID- 9369244 TI - Cardiac myocytes and fibroblasts contain functional estrogen receptors. AB - Gender-based differences found in cardiovascular diseases raise the possibility that estrogen may have direct effects on cardiac tissue. Therefore we investigated whether cardiac myocytes and fibroblasts express functional estrogen receptors. Immunofluorescence demonstrated estrogen receptor protein expression in both female and male rat cardiac myocytes and fibroblasts. Nuclear translocation of the estrogen receptor protein was observed after stimulation of cardiomyocytes with 17beta-estradiol (E2). Cells transfected with an estrogen responsive reporter plasmid showed that treatment with E2 induced a significant increase in reporter activity. Furthermore, E2 induced a significant increase in expression of the estrogen receptors alpha and beta, progesterone receptor and connexin 43 in cardiac myocytes. Cardiac myocytes and fibroblasts contain functional estrogen receptors and estrogen regulates expression of specific cardiac genes. These data suggest that gender-based differences in cardiac diseases may in part be due to direct effects of estrogen on the heart. PMID- 9369245 TI - Mechanisms of cycloheximide-induced apoptosis in liver cells. AB - Cycloheximide in sublethal doses caused apoptosis in liver cells in vivo, inducing c-myc, c-fos, c-jun and p53 genes and accumulation of sphingosine, a toxic product of the sphingomyelin cycle. These data support the hypothesis that continuous synthesis of labile protective proteins is required to restrain apoptosis in liver; sphingosine might be important in mediating cycloheximide induced apoptosis as an endogenous modulator of protein kinase C activity. PMID- 9369246 TI - Small heat shock proteins inhibit in vitro A beta(1-42) amyloidogenesis. AB - We demonstrate that small heat shock proteins (sHsp) inhibit in vitro amyloid formation by the Alzheimer's A beta(1-42) polypeptide as detected by a thioflavine T fluorescence assay and electron microscopy. Human sHsp27 (0.50-3.0 microM) inhibited amyloid formation from 20 microM A beta(1-42) by 23-75%, in 24 h. In contrast, treatment of pre-formed amyloid with 0.5-3.0 microM sHsp27 only reduced the fluorescence signal by 6-36%. The data suggest that ordered fibril formation may represent a form of off-pathway aggregation that can be prevented by chaperone action. The data raise the possibility that age-related changes in chaperone function could contribute toward the pathogenesis of Alzheimer's and other amyloid-associated diseases. PMID- 9369247 TI - A newly identified peptide, proadrenomedullin N-terminal 20 peptide, induces hypotensive action via pertussis toxin-sensitive mechanisms. AB - Proadrenomedullin N-terminal 20 peptide (PAMP) and adrenomedullin (AM) are novel hypotensive peptides. Although they are derived from the same gene product, proadrenomedullin, their hypotensive mechanisms are different; PAMP inhibits the release of norepinephrine from the peripheral sympathetic nerve endings, whereas AM fosters vasodilation by elevating intracellular cAMP, possibly via activation of cholera toxin-sensitive G proteins. In PC12 cells, PAMP inhibited N-type calcium channel via activation of pertussis toxin-sensitive mechanisms. To clarify the relationship between the hypotensive effect of PAMP and pertussis toxin-sensitive mechanisms, we administered pertussis vaccine intraperitoneally into rats for 3 consecutive days. By using mesenteric artery preparation, we showed that PAMP's ability to decrease norepinephrine overflow was significantly attenuated in pertussis toxin-treated rat (-18.5 +/- 6.9%; P<.05 versus control rats). In electrically stimulated pithed rat, PAMP (20 and 40 nmol/kg) showed a hypotensive effect (-13 +/- 5 and -18 +/- 7 mm Hg, respectively; P<.05, P<.01), whereas in pertussis vaccine-treated rat it did not (-2 +/- 3 and -8 +/- 9 mm Hg, respectively; P=NS). Also, in pithed rat, plasma norepinephrine level was significantly elevated by electrical stimulation in both control (0.323 +/- 0.035 ng/mL) and pertussis vaccine-treated groups (0.355 +/- 0.079 ng/mL). After injection of PAMP (40 nmol/kg), plasma norepinephrine level significantly decreased in the control group (0.225 +/- 0.044 ng/mL; P<.01) but not in the pertussis vaccine-treated group (0.392 +/- 0.021 ng/mL; P=NS). Moreover, in conscious rats, intravenous administration of PAMP (40 nmol/kg) did not evoke hypotension after pertussis vaccine treatment, although untreated controls had significantly decreased arterial pressure (-5 +/- 2 versus -20 +/- 3 mm Hg; P<.01). In contrast to PAMP, the administration of AM (1 nmol/kg) significantly reduced the blood pressure of pertussis vaccine-treated as well as control rats ( 20 +/- 5 versus -18 +/- 7 mm Hg; P=NS). These results demonstrate that the ability of PAMP to inhibit norepinephrine release from peripheral sympathetic nerve endings and to decrease blood pressure is pertussis toxin sensitive. Our findings thus suggest that despite being derived from the same gene, PAMP and AM apparently produce hypotension by activating different signaling pathways. PMID- 9369248 TI - High plasma level of N-acetyl-seryl-aspartyl-lysyl-proline: a new marker of chronic angiotensin-converting enzyme inhibition. AB - The acute administration of the angiotensin-converting enzyme (ACE) inhibitor captopril to healthy subjects transiently increases 5.5-fold the plasma levels of a natural stem-cell regulator, N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP). The aim of this study was to measure plasma Ac-SDKP levels during chronic treatment with all types of ACE inhibitors and to assess its relevance as a marker of ACE inhibition. Plasma levels of Ac-SDKP were blindly determined in age and sex-matched hypertensive patients either treated (ACEI group, n=27) or not (non-ACEI group, n=23) with an ACE inhibitor for more than 1 month. Geometric mean [range] of plasma Ac-SDKP levels were significantly higher in the ACEI group (3.78 [1.48 to 14.5] pmol/mL) than in the non-ACEI group, with no overlap between the groups (0.75 [0.36 to 1.22] pmol/mL, P<.0001). The measurement of Ac-SDKP in plasma discriminated all the patients of the ACEI group, whereas the simultaneous determination of either in vitro (using hippuryl-histidine-leucine as substrate) or in vivo (angiotensin II/angiotensin I ratio) ACE activity failed to identify nine and five cases, respectively. We conclude that Ac-SDKP accumulates in plasma during chronic ACE inhibitor treatment. The long-term consequences of Ac-SDKP accumulation are unknown. The reliability of plasma Ac-SDKP measurement makes it the best marker of chronic ACE inhibition, which can help to verify patients' compliance to ACE inhibitor treatment. PMID- 9369249 TI - Antecedent hypertension confers increased risk for adverse outcomes after initial myocardial infarction. AB - Several studies have examined the association of blood pressure (BP) after myocardial infarction (MI) with a risk for adverse outcome; however, few studies have investigated prognosis after MI as a function of BP before MI. Our goal was to examine the relation of antecedent hypertension to risk of adverse outcomes after initial MI. From 1967 to 1990, 404 subjects followed at the Framingham Heart Study developed an initial MI. These subjects were classified on the basis of preinfarction BP into normotensive (BP<140/90 mm Hg and not receiving antihypertensive treatment; n=118), stage I-untreated hypertension (BP 140 to 159/90 to 99 mm Hg; n=89), and stage II to IV or treated hypertension (BP > or =160/100 mm Hg or treated hypertension; n=197). Cox models were used to adjust for age, sex, smoking, glucose intolerance, total cholesterol, and prior cardiovascular disease. Antecedent hypertension was related to risk of adverse outcome after MI. Compared with normotensive individuals, stage II to IV hypertensives were at increased risk for reinfarction (hazard ratio [HR], 2.20; 95% confidence interval [CI], 1.20 to 4.04). A similar but nonsignificant association was seen in stage I hypertensives (HR, 1.91; 95% CI, 0.97 to 3.77). Stage II to IV hypertensives were at increased risk for all-cause mortality compared with normotensive persons (HR, 1.45; 95% CI, 1.07 to 1.98). Thus, even after MI, a history of antecedent hypertension remains predictive of adverse outcome. These findings are consistent with beneficial effects of BP control in primary and secondary prevention settings. Effective BP control may both reduce the risk for an initial MI and improve outcome in the event that an MI occurs. PMID- 9369250 TI - Heritability of left ventricular mass: the Framingham Heart Study. AB - Left ventricular hypertrophy is associated with an increased risk for cardiovascular disease. The known determinants of left ventricular hypertrophy only partially explain its variability. The purpose of this study was to estimate heritability of left ventricular mass. The study sample included adults in the original Framingham Heart Study and the Framingham Offspring Study who were not receiving antihypertensive medications and who were free of coronary heart disease, congestive heart failure, diabetes mellitus, renal insufficiency, valvular heart disease, and severe left ventricular hypertrophy. Intraclass correlations for left ventricular mass among first-degree relatives, second degree relatives, and unrelated spouse pairs were calculated to determine the contribution of heredity to the variability in left ventricular mass. After adjustments for age, height, weight, and systolic blood pressure, the intraclass correlations between first-degree relatives were .15 (parent-child, P<.001) to .16 (siblings, P<.001), between second-degree relatives the correlation was .06 (P=NS), and between spouses it was .05 (P=NS). The estimated heritability of adjusted left ventricular mass was between .24 and .32. The proportion of the variance in sex-specific left ventricular mass explained by age, height, weight, and systolic blood pressure was .26 in men and .34 in women. On the basis of intraclass correlations for left ventricular mass, incorporation of adjusted left ventricular mass of a parent or sibling would increase the explained variance by an additional .02 to .03. Heredity explains a small, but discernible proportion of the variance in left ventricular mass. Studies are currently under way to identify genetic markers that predict an individual's predisposition to left ventricular hypertrophy. This knowledge may lead to advances in the prevention of left ventricular hypertrophy, which is strongly associated with cardiovascular morbidity and mortality. PMID- 9369251 TI - Cardiomyocyte apoptosis and cardiac angiotensin-converting enzyme in spontaneously hypertensive rats. AB - Increased apoptosis has been reported in the heart of rats with spontaneous hypertension and cardiac hypertrophy. This study was designed to investigate the relationship between apoptosis and hypertrophy in cardiomyocytes from the left ventricle of spontaneously hypertensive rats (SHR). In addition, we evaluated whether the development of cardiomyocyte apoptosis is related to blood pressure or to the activity of the local angiotensin-converting enzyme (ACE) in SHR. The study was performed in 16-week-old SHR, 30-week-old untreated SHR, and 30-week old SHR treated with quinapril (10 mg x kg[-1] x d[-1]) during 14 weeks before they were killed. Cardiomyocyte apoptosis was assessed by direct immunoperoxidase detection of digoxigenin-labeled 3'-hydroxyl ends of DNA. Nuclear polyploidization measured by DNA flow cytometry was used to assess cardiomyocyte hypertrophy. Compared with 16-week-old normotensive Wistar-Kyoto rats, 16-week old SHR exhibited increased blood pressure (P<.001), increased rate of tetraploidy (P<.05), and similar levels of ACE activity and apoptosis. Compared with 30-week-old Wistar-Kyoto rats, 30-week-old SHR showed increased blood pressure (P<.001), increased ACE activity (P<.05), increased rate of tetraploidy (P<.01), and increased apoptosis (P<.01). Untreated 30-week-old SHR exhibited similar values of blood pressure and tetraploidy and higher ACE activity (P<.05) and apoptosis (P<.001) than 16-week-old SHR. A direct correlation (P<.01) was found between ACE activity and the apoptotic index in untreated 30-week-old SHR. The long-term administration of quinapril was associated with the normalization of ACE activity and apoptosis in treated SHR. These results suggest that the timing and mechanisms responsible for apoptosis and hypertrophy of cardiomyocytes are different in SHR. Whereas hypertrophy seems to be an earlier alteration that develops in parallel with hypertension, apoptosis develops later in association with overactivity of the local ACE. Our data suggest that cell death dysregulation may be a novel target for antihypertensive agents that interfere with the renin-angiotensin system in hypertension. PMID- 9369252 TI - Effect of nitric oxide on DNA replication induced by angiotensin II in rat cardiac fibroblasts. AB - Our previous in vivo studies (Hou et al. J Clin Invest. 1995;96:2469-2477.) demonstrated that chronic inhibition of nitric oxide synthase led to an exaggerated response to relatively low doses of angiotensin II, resulting in a rapid and marked cardiac fibrosis. To examine further the importance of angiotensin II in inducing cardiac fibrosis and the possibility that nitric oxide serves as a modulator of the proliferative effects of angiotensin II, we used cultured rat cardiac fibroblasts to study the interrelationships between these substances. Angiotensin II induced a delayed DNA synthetic response in quiescent cells that occurred 30 hours after exposure to the hormone. The most pronounced effect of angiotensin II on thymidine uptake occurred 36 to 42 hours after the addition to cells. This response was inhibited in a dose-dependent manner by the addition of either S-nitroso-N-acetylpenicillamine or sodium nitroprusside, each a source of nitric oxide. The nitric oxide donor was most effective in reducing thymidine incorporation when added 12 hours after angiotensin II, whereas the metabolite N-acetylpenicillamine had no effect at any time. The inhibitory effect of S-nitroso-N-acetylpenicillamine was mimicked by 8-bromoguanosine 3':5'-cyclic monophosphate but not by 8-bromoadenosine 3':5'-cyclic monophosphate. Nitric oxide donors did not appear to inhibit the induction of c-fos, Egr-1, or other immediate-early genes in response to angiotensin II. The results suggest that nitric oxide affects the cell cycle following the transition into G, and modulates the proliferation of fibroblasts during cardiac fibrosis induced by angiotensin II. PMID- 9369253 TI - Cardiac myocyte membrane wounding in the abruptly pressure-overloaded rat heart under high wall stress. AB - The potential role of transient sarcolemmal membrane wounding as a signal transduction event for cardiomyocyte hypertrophy was evaluated in rats with short term pressure overload caused by banding of the proximal aorta. This procedure resulted in significant increases in left ventricular systolic (1.5-fold) and end diastolic (2.6-fold) pressures and wall stresses that were associated with significant wall thinning and cavitary enlargement. Quantitative image analysis of frozen sections of the stressed ventricles obtained 60 minutes after banding demonstrated a 6- to 10-fold increase in cytosolic staining with a horseradish peroxidase-labeled anti-albumin antibody compared with sham-operated controls, indicating that an increase in transient sarcolemmal membrane permeability (wounding) is an early response to an abrupt increase in hemodynamic load in vivo. We conclude that an intense hemodynamic stress in vivo can result in histologically detectable cardiomyocyte wounding. PMID- 9369254 TI - Prostacyclin release by rat cardiac fibroblasts: inhibition of collagen expression. AB - Cardiac fibroblasts, as the source of extracellular matrix for the left ventricle, subserve important functions to cardiac remodeling and fibrotic development following myocardial infarction or with pressure-overload cardiac hypertrophy. The fibroblast may be the target cell for angiotensin-converting enzyme inhibitors (ACEI) that are cardioprotective and reverse collagen deposition and remodeling but whose mechanisms of action remain controversial. Because we previously documented phenotypic differences between cardiac fibroblasts from the spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) left ventricle, the present study evaluated whether phenotypic differences also exist in the release of endogenous arachidonic acid metabolites or in the activation of phospholipase D, and the importance of observed differences to the formation of collagen and the mechanism of action of ACEI. The experimental design compared endogenous sources of arachidonic acid with exogenous prelabeling of cells. Angiotensin II stimulated greater arachidonic acid release than bradykinin, and WKY cells were more responsive than SHR. The major prostanoid formed by cardiac fibroblasts was prostaglandin I2 (PGI2), with more prostacyclin production by WKY cells than SHR cells both under nonstimulated conditions and in response to angiotensin II or bradykinin. Beraprost, a PGI2 analogue, was shown to decrease growth rate and DNA synthesis of fibroblasts and to inhibit mRNA expression for collagen types I and III, with SHR cells being less responsive to beraprost than WKY cells. These results potentially implicate eicosanoid metabolism, particularly PGI2, in collagen formation, fibrotic development, and cardiac remodeling, and they imply that the SHR genetic hypertension model may be predisposed to excess cardiac fibrosis. PMID- 9369255 TI - Angiotensin blockade improves cardiac and renal complications of type II diabetic rats. AB - Using Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a new model of human non insulin-dependent diabetes mellitus (NIDDM), we examined the role of local angiotensin II in cardiovascular and renal complications of NIDDM. OLETF rats were orally given cilazapril (an angiotensin-converting enzyme inhibitor, 1 or 10 mg/kg), E4177 (an angiotensin AT1 receptor antagonist, 10 mg/kg), or vehicle for 26 or 40 weeks (from the age of 20 to 46 or 60 weeks). Cardiac mRNAs were measured by Northern blot analysis, and the thickening of the coronary arterial wall and the degree of perivascular fibrosis were determined by an image analyzer. Cilazapril or E4177 did not significantly affect body weight or plasma glucose and insulin levels of OLETF rats, indicating the minor effects on diabetes itself. However, both drugs significantly and similarly prevented coronary microvascular remodeling (the increase in wall thickening and perivascular fibrosis in coronary arterioles and small coronary arteries) in OLETF rats, and they were associated with the suppression of cardiac transforming growth factor-beta1 expression. Both drugs suppressed not only the increase in left ventricular weight but also the downregulation of cardiac alpha-myosin heavy chain expression in OLETF rats. Glomerulosclerosis and glomerular hypertrophy in OLETF rats were improved by cilazapril and E4177 to a comparable extent. These results, taken together with the fact that OLETF rats show normal plasma renin levels, support that the AT1 receptor is involved in the pathogenesis of cardiac and renal complications in NIDDM. PMID- 9369256 TI - The hypertension of autonomic failure and its treatment. AB - We studied the incidence and severity of supine hypertension in 117 patients with severe primary autonomic failure presenting to a referral center over a 9-year period. Patients were uniformly characterized by disabling orthostatic hypotension, lack of compensatory heart rate increase, abnormal autonomic function tests, and unresponsive plasma norepinephrine. Fifty-four patients had isolated autonomic impairment (pure autonomic failure). Sixty-three patients had central nervous system involvement in addition to autonomic impairment (multiple system atrophy). Patients were studied off medications, in a metabolic ward, and on a controlled diet containing 150 mEq of sodium. Fifty-six percent of patients had supine diastolic blood pressure > or =90 mm Hg. The prevalence of hypertension was slightly greater in females (63%) than in males (52%). Potential mechanisms responsible for this hypertension were investigated. No correlation was found between blood volume and blood pressure. Similarly, plasma norepinephrine (92+/-15 pg/mL) and plasma renin activity (0.3+/-0.05 ng/mL per hour) were very low in the subset of patients with pure autonomic failure and supine hypertension (mean systolic/diastolic pressure, 177 +/- 6/108 +/- 2 mm Hg, range 167/97 to 219/121). Supine hypertension represents a challenge in the treatment of orthostatic hypotension. We found these patients to be particularly responsive to the hypotensive effects of transdermal nitroglycerin. Doses ranging from 0.025 to 0.1 mg/h decreased systolic blood pressure by 36+/-7 mm Hg and may effectively treat supine hypertension overnight, but the dose should be individualized and used with caution. PMID- 9369257 TI - Identification of a renin threshold and its relationship to salt intake in a patient with pure autonomic failure. AB - Animal studies have demonstrated a threshold below which renin release increases proportionally to a decrease in renal perfusion pressure. Demonstration of a similar mechanism in humans, however, has proved difficult, as any attempt to lower blood pressure below the putative renin threshold results in renin release mediated by reflex activation of the sympathetic nervous system. In this study, we report on our observations in a 71-year-old woman who presented with a 20-year history of faintness and syncope and was diagnosed as having pure autonomic failure. Graded head-up tilting resulted in a stepwise reduction in mean arterial blood pressure to a minimum of 54 mm Hg, with no signs of increased sympathetic activity. A fall in blood pressure below 80 mm Hg resulted in a distinct rise in plasma renin activity, and a similar threshold pressure was observed under both a 50- and a 100-mmol/d sodium chloride diet. Below the threshold, response to changes in perfusion pressure was proportionally greater under the 50-mmol/d diet than under a 100- or 200-mmol/d diet. These observations demonstrate that a pressure threshold for renin release at 10 to 15 mm Hg below ambient blood pressure, as described previously in animal studies, is also present in humans. The significance of this pressure-dependent mechanism of renin release for the long-term regulation of blood pressure and water and mineral balance in humans remains to be determined. PMID- 9369258 TI - Malignant vagotonia due to selective baroreflex failure. AB - Baroreflex failure is characterized by dramatic fluctuations of sympathetic activity and paroxysms of hypertension and tachycardia. In contrast, unopposed parasympathetic activity has not been described in patients with baroreflex failure because of concurrent parasympathetic denervation of the heart. We describe the unusual case of a patient with baroreflex failure in a setting of preserved parasympathetic control of HR manifesting episodes of severe bradycardia and asystole. Thus, parasympathetic control of the HR may be intact in occasional patients with baroreflex failure. Patients with this selective baroreflex failure require a unique therapeutic strategy for the control of disease manifestations. PMID- 9369259 TI - Norepinephrine release in the human forearm: effects of epinephrine. AB - It has been postulated that delayed facilitation of norepinephrine release by epinephrine is causally related to the development of hypertension. It has been proposed that a brief increase in epinephrine concentrations results in the uptake of epinephrine into the sympathetic nerve terminal. Subsequent rerelease of epinephrine stimulates presynaptic beta-adrenergic receptors, resulting in a prolonged increase in plasma norepinephrine (NE) concentrations, with amplified sympathetic responses and vasoconstriction. To determine whether such epinephrine induced, delayed facilitation of NE release occurs in a vascular bed draining resistance vessels and, if it occurs, whether that facilitation differs in hypertension, we used a radioisotope dilution method to measure unstimulated and isoproterenol-stimulated forearm NE spillover before, during, and after a 50 ng/min infusion of epinephrine for 30 minutes directly into the brachial artery. No delayed facilitatory effects of epinephrine on forearm NE spillover were observed in either 6 normotensive (NT) or 8 borderline hypertensive (BHT) subjects (NT unstimulated forearm NE spillover preepinephrine 1.79+/-0.41 ng/min versus postepinephrine 2.36+/-0.65 ng/min, P=.38; BHT preepinephrine 2.24+/-0.70 ng/min versus postepinephrine 1.93+/-0.46 ng/min, P=.51; NT isoproterenol stimulated forearm NE spillover preepinephrine 4.61+/-1.01 ng/min versus postepinephrine 4.4+/-0.98 ng/min, P=.9; BHT preepinephrine 4.04+/-1.36 ng/min versus postepinephrine 4.69+/-1.49 ng/min P=.5). We conclude that the short-term local infusion of epinephrine does not have a delayed facilitatory effect on forearm NE spillover in NT or BHT subjects. Therefore, the prolonged increase in NE concentrations after epinephrine infusion previously shown systemically, and not seen locally in the forearm, suggests that the delayed facilitatory response to epinephrine may occur in other organs. PMID- 9369260 TI - Effect of sympathectomy on mechanical properties of common carotid and femoral arteries. AB - Sympathetic stimulation is accompanied by a reduction of arterial distensibility, but whether and to what extent elastic and muscle-type arterial mechanics is under tonic sympathetic restraint is not known. We addressed this issue by measuring, in the anesthetized rat, the diameters of the common carotid and femoral arteries with an echo-Doppler device (NIUS 01). Blood pressure was measured by a catheter inserted contralaterally and symmetrically to the vessel where the diameter was measured. Arterial distensibility over the systolic diastolic pressure range was calculated according to the Langewouters formula. Data were collected in 10 intact (vehicle pretreatment) and 9 sympathectomized (6 hydroxydopamine pretreatment) 3-month-old Wistar-Kyoto rats. Compared with the intact animals, sympathectomized rats showed a marked increase in arterial distensibility over the entire systolic-diastolic pressure range. When quantified by the area under the distensibility-pressure curve, the increase was 59% and 62% for the common carotid and femoral arteries, respectively (P<.01 for both). In the femoral but not in the common carotid artery, sympathectomy was accompanied also by an increase in arterial diameter (+18%, P<.05 versus intact). Therefore, in the anesthetized normotensive rat, sympathetic activity exerts a tonic restraint on large-artery distensibility. This restraint is pronounced in elastic vessels and even more pronounced in muscle-type vessels. PMID- 9369261 TI - Reflex effects on renal nerve activity characteristics in spontaneously hypertensive rats. AB - The effects of arterial and cardiac baroreflex activation on the discharge characteristics of renal sympathetic nerve activity were evaluated in conscious spontaneously hypertensive and Wistar-Kyoto rats. In spontaneously hypertensive rats compared with Wistar-Kyoto rats, (1) arterial baroreflex regulation of renal sympathetic nerve activity was reset to a higher arterial pressure and the gain was decreased and (2) cardiac baroreflex regulation of renal sympathetic nerve activity exhibited a lower gain. With the use of sympathetic peak detection analysis, the inhibition of integrated renal sympathetic nerve activity, which occurred during both increased arterial pressure (arterial baroreflex) and right atrial pressure (cardiac baroreflex), was due to parallel decreases in peak height with little change in peak frequency in both spontaneously hypertensive and Wistar-Kyoto rats. Arterial and cardiac baroreflex inhibition of renal sympathetic nerve activity in Wistar-Kyoto and spontaneously hypertensive rats is due to a parallel reduction in the number of active renal sympathetic nerve fibers. PMID- 9369262 TI - Effects of chronic nitric oxide synthase inhibition on cerebral arterioles in rats. AB - We examined the effects of nitric oxide (NO) synthase inhibition on the structure and mechanics of cerebral arterioles. We measured pressure, diameter, and cross sectional area of the vessel wall (histologically) in maximally dilated cerebral arterioles in Sprague-Dawley rats that were untreated or treated for 3 months with the NO synthase inhibitor N-nitro-L-arginine methyl ester (L-NAME; 10 mg/kg per day). Treatment with L-NAME increased cerebral arteriolar mean (87+/-6 versus 42+/-2 mm Hg, P<.05) and pulse (25+/-2 versus 13+/-2 mm Hg, P<.05) pressures, as well as cross-sectional area of the vessel wall (1839+/-70 versus 1019+/-58 microm2, P<.05) and external diameter (101+/-4 versus 87+/-2 microm, P<.05). These findings suggest that hypertension induced by NO synthase inhibition is accompanied by hypertrophy of the vessel wall and enlargement of cerebral arterioles in rats. To determine the role of cerebral arteriolar pulse pressure in hypertrophy of cerebral arterioles during inhibition of NO synthase, we measured the cross-sectional area of the vessel wall in rats treated with L-NAME that underwent unilateral carotid clipping. Unilateral carotid clipping failed to prevent increases in cross-sectional area of the vessel wall (1507+/-173 and 1613+/-148 microm2 in the clip and sham sides, respectively) in rats treated with L-NAME, even though increases in pulse pressure were prevented (16+/-1 and 27+/-1 mm Hg in the clip and sham sides, respectively, P<.05). These findings suggest that inhibition of NO synthase may promote hypertrophy of cerebral arterioles independently of increases in arteriolar pulse pressure. PMID- 9369263 TI - Role of endothelial kinins in control of coronary nitric oxide production. AB - The purpose of the present study was to determine whether interventions that promote kinin production or decrease kinin inactivation affect nitric oxide production in isolated canine coronary microvessels. Accordingly, bradykinin (10[ 8] to 10[-5] mol/L), ramiprilat (10[-10] to 10[-8] mol/L), A23187 (10[-8] to 10[ 6] mol/L), kallikrein (1 to 20 U/mL), and kininogen (0.5 to 10 microg/mL) were used to stimulate endothelium-dependent nitric oxide production. Receptor antagonists, serine protease inhibitors, and a kinin antibody were used to inactivate local kallikrein-kinin activity. Nitrite, the metabolite of nitric oxide in aqueous solution, was measured using the Griess reaction. All the agonists significantly increased nitrite release. For instance, the highest dose of bradykinin, ramiprilat, A23187, kallikrein, and kininogen markedly increased nitrite production, from 60+/-10 to 156+/-12, 153+/-11, 161+/-15, 176+/-15, and 168+/-16 pmol/mg (all P<.05), respectively. The increased nitrite production caused by these agents was not only blocked by N omega-nitro-L-arginine methyl ester (L-NAME) and HOE 140 (which blocks B2 kinin receptor) but by the kinin antibody also. For instance, nitrite production elicited by bradykinin, ramiprilat, A23187, and kininogen was reduced to 95+/-8, 87+/-8, 94+/-11, and 85+/-11 pmol/mg (all P<.05), respectively, by the kinin antibody. Carbachol induced nitrite production (from 66+/-8 to 144+/-13) was blocked by L-NAME but not by HOE 140 or the kinin antibody. These results suggest that either increasing kininogen to promote endogenous kinin formation or inhibiting angiotensin-converting enzyme to decrease kinin breakdown, increases nitric oxide production in isolated coronary microvessels. These data indicate that a microvessel kallikrein-kinin system has an important role in the control of nitric oxide production in coronary microvessels. PMID- 9369264 TI - Arginine vasopressin increases nitric oxide synthesis in cytokine-stimulated rat cardiac myocytes. AB - We investigated the effects of arginine vasopressin (AVP) on nitric oxide (NO) synthase activity in cardiac myocytes by measuring the production of nitrite, a stable metabolite of NO, and the expression of inducible NO synthase (iNOS) mRNA and protein. Incubation of cultured neonatal rat cardiac myocytes for 24 hours with interleukin-1beta (IL-1beta) caused a significant increase in NO production. Both AVP and V1a receptor agonist [Phe2,Ile3,Orn8]vasopressin augmented NO synthesis in IL-1beta-stimulated, but not in unstimulated myocytes, in a dose dependent manner. The V1a receptor antagonist [d(CH2)[5]1,O-Me Tyr2,Arg8]vasopressin completely inhibited the effect of AVP. The AVP-induced NO production by IL-1beta-stimulated cells was accompanied by increased iNOS mRNA and protein accumulation. AVP caused a significant increase in cytosolic free Ca2+ levels of cardiac myocytes, whereas it showed no effect on cytosolic cAMP levels. After protein kinase C activity was functionally depleted by treating cells with phorbol 12-myristate 13-acetate for 24 hours, AVP did not augment IL 1beta-induced NO production. The effect of AVP was also inhibited in the presence of the protein kinase C inhibitor calphostin C. The addition of AVP increased protein kinase C activity in cardiac myocytes, and its effect was significantly inhibited in the presence of calphostin C. These results support the hypothesis that the heart may be a target organ for AVP and that AVP modulates IL-1beta induced iNOS expression in myocytes through the V1a receptor, which is mediated at least partially via activation of protein kinase C. PMID- 9369265 TI - Effects of SR 49059, a new orally active and specific vasopressin V1 receptor antagonist, on vasopressin-induced vasoconstriction in humans. AB - We have evaluated the efficacy of SR 49059, a new orally active and specific vasopressin V1 receptor antagonist (arginine-vasopressin [AVP]), in the blockade of the vascular effects of exogenous AVP in healthy subjects. In preliminary experiments, two procedures to measure the V1 vascular effects of AVP were assessed. First, the AVP-induced changes in skin blood flow were investigated by the injection of increasing doses of AVP intradermally, with or without a previous local vasodilation with calcitonin gene-related peptide (CGRP). In a second protocol, AVP was infused intra-arterially, and the changes in radial artery diameter and blood flow were measured. The intradermal injection of AVP caused significant decreases in skin blood flow, and the use of CGRP increased the sensitivity of the method by a factor of 10(2) to 10(3). AVP infused intra arterially caused dose-dependent decreases in the radial artery diameter and blood flow. In the main study, the potency and efficacy of SR 49059 to block the AVP-induced changes in skin blood flow were assessed in 12 healthy men with a double-blind, triple crossover study design. The subjects were randomized to receive a placebo orally and 30 mg and 300 mg of the antagonist at a 1-week interval. The subjects were then further randomized to evaluate the efficacy of the same doses of the antagonist to block the vasoconstriction of the radial artery induced by an intra-arterial infusion of AVP. SR 49059 inhibits, dose dependently and significantly, the AVP-induced changes in skin blood flow, with a peak effect occurring between 2 and 6 hours after injection. In addition, the 300 mg dose of SR 49059 completely blocked the vasoconstriction of the radial artery induced by AVP. In conclusion, skin blood-flow measurement, after intradermal injection of AVP on a skin area vasodilated with CGRP, is an effective method to investigate the V1 vascular effect of AVP in humans. SR 49059 is a potent and specific antagonist of V1 receptors, which blocks the AVP-induced vasoconstriction. PMID- 9369266 TI - Insulin enhances endothelial alpha2-adrenergic vasorelaxation by a pertussis toxin mechanism. AB - To investigate whether insulin effect on endothelium is related to a specific signal transduction pathway or reflects a more generalized action of the hormone, we studied in aortic rings of Wistar-Kyoto (WKY) rats the effects of the hormone on endothelium-dependent relaxations generated by acetylcholine, adenosine diphosphate, the selective alpha2-adrenergic agonist UK 14,304, and the calcium ionophore ionomycin. The responses were evaluated both in control conditions and after 30 minutes of exposure to three different levels of insulin (30, 100, and 500 microU/mL). Insulin failed to modify the phenylephrine aortic contractions and the relaxations induced by acetylcholine, adenosine diphosphate, and ionomycin. In contrast, both 100 and 500 microU/mL insulin were able to potentiate the UK 14,304-induced vasorelaxation (+96+/-19% and +91+/-12%, respectively). Pertussis toxin, which causes alpha2-adrenergic receptor Gi uncoupling, reduced the alpha2-adrenergic vasorelaxation and prevented the insulin potentiation of the response to UK 14,304. Furthermore, in primary cultured aortic endothelial cells from WKY, we evaluated the conversion of [3H]arginine to [3H]citrulline in response to acetylcholine, ionomycin, and UK 14,304, both in control conditions and during insulin exposure. Again, insulin did not affect basal citrulline production or the increase induced by acetylcholine and ionomycin, whereas it potentiated the response to UK 14,304. Finally, in aortic rings of spontaneously hypertensive rats, insulin treatment (100 and 500 microU/mL) was unable to enhance the alpha2-adrenergic vasodilator response; in vascular endothelial cells from spontaneously hypertensive rats, insulin did not potentiate the increase in citrulline production evoked by UK 14,304. In conclusion, insulin selectively enhances alpha2-adrenergic endothelial vasorelaxation through a pertussis toxin-sensitive mechanism, by potentiating endothelial nitric oxide production. This vasorelaxant mechanism is altered in spontaneously hypertensive rats. PMID- 9369268 TI - Insulin resistance, hyperinsulinemia, and blood pressure: role of age and obesity. European Group for the Study of Insulin Resistance (EGIR). AB - In population surveys, blood pressure and plasma insulin concentration are related variables, but the association is confounded by age and obesity. Whether insulin resistance is independently associated with higher blood pressure in normal subjects is debated. We analyzed the database of the European Group for the Study of Insulin Resistance, made up of nondiabetic men and women from 20 centers, in whom insulin sensitivity was measured by the euglycemic insulin clamp. After excluding subjects aged > or =70 years, those with severe obesity (body mass index [BMI] >40 kg x m[-2]), and those with abnormal blood pressure values (> or =140/90 mm Hg), 333 cases (ages 18 to 70 years; BMI, 18.4 to 39.8 kg x m[-2]) were available for analysis. In univariate analysis, both systolic and diastolic blood pressures were inversely related to insulin sensitivity, with r values of 0.18 (P<.005) and 0.34 (P<.0001), respectively. In a multivariate model simultaneously accounting for sex, age, BMI, and fasting insulin, systolic and diastolic blood pressures were still inversely related to insulin sensitivity (partial r, 0.15 and 0.19; P<.01 for both). In this model, age was positively related to blood pressure levels independently of insulin sensitivity, whereas BMI was not. The predicted impact on blood pressure of a decrease in insulin sensitivity of 10 micromol x min(-1) x kg(-1) was +1.4 mm Hg, similar to that associated with a 10-year difference in age. Although insulin levels and insulin action were reciprocally interrelated, diastolic blood pressure varied as a simultaneous function of both. In normotensive, nondiabetic Europeans, insulin sensitivity and age are significant, mutually independent correlates of blood pressure, whereas body mass is not. The relation of blood pressure to both insulin action and circulating insulin levels is compatible with distinct influences on blood pressure by insulin resistance and compensatory hyperinsulinemia. PMID- 9369267 TI - Prevalence and clinical correlates of microalbuminuria in essential hypertension: the MAGIC Study. Microalbuminuria: A Genoa Investigation on Complications. AB - The prevalence of microalbuminuria and its relationship with several cardiovascular risk factors and target organ damage were evaluated in a cohort of 787 untreated patients with essential hypertension. Albuminuria was measured as the albumin-to-creatinine ratio in three nonconsecutive, first morning urine samples. The prevalence of microalbuminuria was 6.7%. Albuminuric patients were more likely to be men and to be characterized by higher blood pressure, body mass index, and uric acid levels and lower HDL cholesterol and HDL cholesterol-to-LDL cholesterol ratio. Piecewise linear regression analysis demonstrated that uric acid and diastolic blood pressure significantly influence albuminuria and together account for a large part of its variations. K-means cluster analysis performed on the entire cohort of patients confirmed that microalbuminuria is associated with a worse cardiovascular risk profile. Furthermore, microalbuminuria was associated with the presence of target organ damage (eg, electrocardiographic [ECG] abnormalities and retinal vascular changes). Age and the presence of microalbuminuria act as independent risk factors for the development of ECG abnormalities and retinal vascular changes. Cluster analysis allowed us to identify three subgroups of patients who differed in the presence or absence of microalbuminuria, retinopathy, and ECG abnormalities. We conclude that the prevalence of microalbuminuria in essential hypertension is lower than previously reported. Increased urinary albumin excretion is associated with a worse cardiovascular risk profile and is a concomitant indicator of early target organ damage. PMID- 9369269 TI - Fatty acids, not insulin, modulate alpha1-adrenergic reactivity in dorsal hand veins. AB - Resistance to the vasodilator action of insulin and its capacity to antagonize vascular alpha-adrenergic reactivity may contribute to the increased neurovascular tone and blood pressure in obese hypertensive subjects. We showed that nonesterified fatty acids (NEFAs) were elevated in obese hypertensive subjects and that raising NEFAs locally in dorsal hand veins of healthy normotensive subjects enhances alpha1adrenoceptor reactivity. Research by others suggests that insulin antagonizes alpha1-adrenoceptor tone in dorsal hand veins. Taken together with evidence that NEFAs antagonize several of the metabolic actions of insulin, these observations raise the possibility that NEFAs participate in resistance to the vascular effects of insulin and suggest that dorsal hand veins represent a good model for studying these interactions. Thus, we produced local hyperinsulinemia in the dorsal hand veins of six lean normal volunteers and quantified changes of venous distensibility in response to phenylephrine in the presence and absence of a local elevation of NEFAs. We confirmed that raising NEFAs locally decreased by twofold to threefold the phenylephrine ED50 (P<.01), but this alpha1-sensitizing action of NEFAs was not antagonized by insulin concentrations up to approximately 1000 microU/mL. Moreover, local hyperinsulinemia alone did not affect vascular alpha1-adrenergic sensitivity as measured by the phenylephrine ED50. To address the possibility that the absence of an insulin effect reflected a lack of nitric oxide-mediated, endothelium-dependent dilation in hand veins, responses to acetylcholine were obtained. Acetylcholine relaxed preconstricted hand veins by 60% to 80% (P<.01) in the presence and absence of indomethacin, which suggests substantial endothelium-dependent, cyclooxygenase-independent vasodilation. The results confirm that raising NEFAs locally enhances vascular alpha1-adrenoceptor sensitivity. Despite the presence of significant endothelium-dependent dilation in dorsal hand veins, insulin does not antagonize vascular alpha1-adrenoceptor sensitivity in the presence of either ambient or locally elevated fatty acids. PMID- 9369270 TI - Angiotensin II affects basal, pulsatile, and glucose-stimulated insulin secretion in humans. AB - Angiotensin II (Ang II) modulates the tissue response to insulin (insulin sensitivity), but the effect of Ang II on the secretion of insulin has not been investigated thus far. Nineteen healthy volunteers (17 male; mean age, 26+/-1 years) were studied. In a double-blind, randomized, placebo-controlled study, seven volunteers were allocated on three occasions in random order after an overnight fast to three interventions: (1) solvent (placebo) infusion; (2) infusion of 1.0 ng Ang II x kg(-1) x min(-1) (subpressor dose); and (3) infusion of 5.0 ng Ang II x kg(-1) x min(-1) (pressor dose). Frequent blood samples (each minute) were obtained for estimation of plasma insulin concentrations over a period of 120 minutes to assess basal and pulsatile insulin secretion. In an ancillary study, plasma glucose and insulin levels were measured after an oral glucose tolerance test while solvent (placebo) or Ang II was infused in 12 fasting healthy volunteers. Plasma insulin concentrations were measured immunoenzymatically (enzyme-linked immunosorbent assay). Insulin secretion pulses were analyzed with the deconvolution technique, and the regularity of insulin secretion was analyzed with the approximate entropy technique. Plasma insulin half-life was assessed using the hyperinsulinemic euglycemic clamp method. The pressor dose of Ang II reduced total, basal, and pulsatile insulin secretion, and this effect was highly significant (P<.01). The subpressor dose tended to suppress insulin secretion. The burst frequency (number of peaks) and the regularity of insulin secretion were not affected by administration of Ang II. After the oral glucose load, the insulinemic response was significantly lower and plasma glucose concentrations were significantly higher with infusion of Ang II compared with placebo. Ang II affects both the basal (nonpulsatile) and the pulsatile component of spontaneous insulin secretion and the glucose-stimulated insulin secretion in humans. This observation is of potential interest with respect to the interaction of Ang II and insulin, eg, in the genesis of hyperinsulinemia and hypertension. PMID- 9369271 TI - Sodium, blood pressure, and arterial distensibility in insulin-dependent diabetes mellitus. AB - We investigated 24-hour ambulatory blood pressure and arterial distensibility, a marker of biophysical vessel wall properties, in 32 normoalbuminuric type I diabetic patients and 32 healthy control subjects on diets containing 50 mmol and 200 mmol sodium per day. The increase in daytime diastolic blood pressure from 50 to 200 mmol sodium was significantly higher in the diabetic patients than in the control subjects (2.3+/-4.9 versus 0.2+/-3.7 mm Hg, P<.05). On a high sodium regimen, femoral artery distensibility was decreased in the diabetic patients compared with the control subjects (19.2+/-7.6 versus 24.1+/-9.3 10[-3]/kPa, P<.05). Angiotensin-converting enzyme inhibition in the diabetic patients on a high sodium diet decreased daytime diastolic blood pressure and increased femoral artery distensibility. The blood pressure decrease in response to angiotensin converting enzyme inhibition correlated significantly with the blood pressure increase to sodium (for 24-hour systolic and diastolic blood pressure, r=.72, P<.001 and r=.76, P<.001). In addition, we found that in the diabetic patients on a high sodium diet, the renal blood flow response to exogenous angiotensin II was not bimodally distributed, as is the case in essential hypertension, in which a subgroup of the patients are characterized by sodium sensitivity of the blood pressure and an abnormal renal blood flow response to exogenous angiotensin II ("nonmodulator phenotype"). These results show that blood pressure in insulindependent diabetes mellitus is sodium sensitive, but that this is not related to the nonmodulator phenotype, and suggest that in IDDM a relatively high sodium intake may be a factor that predisposes to the development of diabetic vascular disease. PMID- 9369272 TI - Vasodilators, aortic elasticity, and ventricular end-systolic stress in nonanesthetized unrestrained rats. AB - We evaluated the effect of different vasodilators on ventricular end-systolic stress by investigating the impact of sodium nitroprusside, nifedipine, and hydralazine on blood pressure, aortic stiffness, and wave reflection during drug induced hypotension (to 80 mm Hg mean blood pressure) in normotensive (central aortic mean blood pressure, 116 to 119 mm Hg; systolic pressure, 133 to 137 mm Hg), nonanesthetized, unrestrained rats. Aortic stiffness was evaluated from the slope of the linear regression relating pulse wave velocity (PWV) to central aortic mean or pulse pressure. The fall in central aortic systolic blood pressure was less than the fall in mean pressure, especially after hydralazine (122+/-4 mm Hg; sodium nitroprusside, 107+/-2; and nifedipine, 112+/-3 mm Hg; P<.05). The PWV/mean pressure slope was linear, positive, and similar in all three groups (hydralazine, 3.3+/-0.2; sodium nitroprusside, 3.8+/-0.3; and nifedipine, 3.9+/ 0.3 cm x s[-1]x mm Hg[-1]; P>.05). The PWV/pulse pressure slope was linear, negative, and less steep in the case of hydralazine (-4.9+/-0.6; sodium nitroprusside, -15.5+/-3.7; and nifedipine, -13.5+/-2.9 cm x s[-1] x mm Hg[-1]; P<.05). The travel time and augmentation index of the reflected wave were similar in all groups. In conclusion, sodium nitroprusside and nifedipine had a more beneficial effect on end-systolic stress than did hydralazine. This does not appear to be related to any specific effect on wave reflection or the "static" relationship between PWV and aortic mean blood pressure; it may be related to the effects of these drugs on the "dynamic" relationship between PWV and pulse pressure. PMID- 9369273 TI - Interactions between nitric oxide and angiotensin II on renal cortical and papillary blood flow. AB - This study examined the role of angiotensin II (Ang II) on the effects of nitric oxide (NO) synthesis blockade on renal cortical and papillary blood flow in innervated and denervated kidneys of volume-expanded Munich-Wistar rats with hormonal influences on the kidney that were held constant by intravenous infusion. Cortical (CBF) and papillary (PBF) blood flow were measured by laser Doppler flowmetry. A low dose of N omega-nitro-L-arginine methyl ester (L-NAME, 3.7 nmol x kg[-1] x min[-1]) reduced CBF only in innervated kidneys, and this effect was abolished by subsequent administration of valsartan (an AT1 antagonist). L-NAME 3.7 nmol x kg(-1) x min(-1) improved PBF autoregulation by lowering PBF to the range of 100 to 140 mm Hg of perfusion pressure, and this effect was attenuated or abolished by valsartan in innervated and denervated kidneys, respectively. These results indicate that the cortical and medullary vasoconstriction induced by a low dose of L-NAME are caused by potentiation of the vasoconstrictor influence of renal sympathetic nerves and Ang II. A higher dose of L-NAME (37 nmol x kg[-1] x min[-1]) lowered CBF and PBF in both innervated and denervated kidneys. This effect of L-NAME on the cortical circulation was abolished by valsartan, but this AT1 antagonist had no effect on the medullary vasoconstriction produced by NO synthesis blockade. Therefore, a higher dose of L-NAME induces a renal cortical vasoconstriction through potentiation of the renin-angiotensin system, whereas the fall of PBF seen after L-NAME 37 nmol x kg(-1) x min(-1) seems to be caused primarily by NO suppression. This Ang II potentiation produced by L-NAME in the renal cortex seems to be mediated by AT1 receptors, because it was unaffected by PD123319 (an AT2 antagonist). The results of the present study indicate that NO is an important modulator of the vasoconstrictor influence of Ang II in the renal cortical circulation of the rat. However, although there are some interactions between NO and renal nerves and Ang II on the medullary circulation, the renal medullary vasoconstriction produced by L-NAME appears to be caused primarily by NO suppression, with little influence of the renal vasoconstrictor systems. PMID- 9369274 TI - Angiotensin-converting enzyme inhibition alters nitric oxide and superoxide release in normotensive and hypertensive rats. AB - Young (approximately 1 month old) male normotensive Wistar-Kyoto rats (n=26) and spontaneously hypertensive rats (n=38) were randomized into three groups treated via drinking water for approximately 2 years with, respectively, placebo, low doses, or high doses of an angiotensin-converting enzyme inhibitor, ramipril (10 microg x kg[-1] x d[-1], non-blood pressure-lowering dose, or 1 mg x kg[-1] x d[ 1], blood pressure-lowering dose). Relative to placebo treatment in each respective rat strain, both ramipril dosages increased endothelial constitutive nitric oxide synthase expression (Western blot) and resultant synthesis of nitric oxide (porphyrinic sensor) in freshly excised carotids and thoracic aortas, respectively. Paradoxically, this activity was associated with an increased/decreased superoxide accumulation (chemiluminescence) in freshly excised aortas from 24-/22-month-old normotensive/hypertensive rats. In normotensive rats, relative to placebo treatment, the threefold increase in superoxide accumulation with antihypertensive ramipril treatment is most likely from the >300% increase in endothelial constitutive nitric oxide synthase expression (some of which may be disarranged by local insufficiencies in L arginine or tetrahydrobiopterin). In hypertensive rats, relative to placebo treatment, the 35% increase in nitric oxide availability by long-term antihypertensive ramipril treatment may contribute to the preservation of the endothelium and prevent its dysfunction by inhibiting superoxide production. Increased nitric oxide production with concomitant decreased superoxide accumulation (approximately one third of placebo levels) correlates positively with the previously reported +40% life span extension for rats with genetic hypertension that were treated with antihypertensive doses of ramipril. PMID- 9369275 TI - Endogenous angiotensin II produced by endothelium regulates interleukin-1beta stimulated nitric oxide generation in rat isolated vessels. AB - The endothelium is a source of several factors that regulate vascular functions. Angiotensin II is one of the main active factors released by the endothelium. The aim of the present work was to analyze the role of angiotensin II released by the endothelium in the regulation of the inducible nitric oxide synthase expression in rat isolated aortic vessels. Interleukin-1beta (0.03 U/L) stimulated nitrite release by the aortic vessels. The nitrite released was less in vessels with endothelium than in deendothelialized aortic segments. This effect was accompanied by a reduced expression of the inducible nitric oxide synthase in the aortic rings with endothelium. Exogenous angiotensin II inhibited IL-1beta stimulated inducible nitric oxide synthase protein expression in both deendothelialized vessels and those with endothelium, although with reduced ability on the aortic segments with endothelium by a nitric oxide-independent mechanism. In the aortic rings with endothelium, either inhibition of the AT-1 receptor with losartan or blocking of angiotensin II generation with fosinopril enhanced interleukin-1beta-stimulated inducible nitric oxide synthase protein expression. In conclusion, the endothelium decreases inducible nitric oxide synthase expression in the vascular wall. Angiotensin II released from endothelial cells is a main mediator responsible for this inhibition through an AT-1-type receptor-dependent mechanism. PMID- 9369276 TI - Endothelin-1 as an autocrine/paracrine apoptosis survival factor for endothelial cells. AB - Endothelin-1 (ET-1), an endothelium-derived vasoactive peptide, functions as a potent vasoconstrictor as well as mitogen. We show here a novel role for ET-1 as an apoptosis survival factor for cultured rat endothelial cells. When we rendered endothelial cells obtained from rat aorta quiescent by serum starvation, significant portions of cultured cells underwent apoptotic death as demonstrated by nucleosomal laddering on agarose gel electrophoresis, flow cytometry analysis with FACS, and the TdT-mediated dUTP biotin nick-end labeling (TUNEL) method. ET 1 dose-dependently (10[-12] to 10[-6] mol/L) suppressed the apoptosis induced by serum starvation. The ET(B) receptor antagonist (BQ788; 10[-6] mol/L) and ET(A/B) receptor antagonists (PD142893 and PD145065; 10[-6] mol/L), but not the ET(A) receptor antagonist (BQ123; 10[-6] mol/L), blocked the apoptosis protective effect of 10[-7] mol/L ET-1. Nonimmune rabbit serum reduced the apoptotic event induced by serum deprivation, whereas neutralization of endogenous ET-1 by polyclonal anti-ET-1 antiserum abrogated this protective effect. The ET(B) receptor antagonist (BQ788; 10[-8] to 10[-6] mol/L), but not the ET(A) receptor antagonist (BQ123; 10[-8] to 10[-6] mol/L), significantly inhibited proliferation of endothelial cells. These data suggest that ET-1, as well as mitogen, functions as an apoptosis survival factor for endothelial cells in an autocrine/paracrine manner via the ET(B) receptor. PMID- 9369277 TI - ET(B) receptor and nitric oxide synthase blockade induce BQ-123-sensitive pressor effects in the rabbit. AB - Endothelin-1 (0.25 nmol/kg, injected into the left cardiac ventricle) induces a protracted increase of mean arterial pressure that is significantly reduced by the selective ET(A) receptor antagonist BQ-123 (1 and 10 mg/kg) in the anesthetized rabbit. The sole administration of the selective ET(B) antagonist BQ 788 (0.25 mg/kg) induces a pressor response abolished by BQ-123 (1 mg/kg). Concomitant to the increase in mean arterial pressure, BQ-788 induces a significant increase in plasma levels of endothelin-1 and its precursor big endothelin-1. The nitric oxide synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME; 10 mg/kg) also increases arterial blood pressure, and the response is reduced dose-dependently by BQ-123 (1 and 10 mg/kg). In addition, the administration of BQ-788 in the presence of L-NAME induced a further increase in arterial blood pressure. The duration of the pressor response to L-NAME is also significantly reduced by an endothelin-converting enzyme inhibitor, phosphoramidon (10 mg/kg). Finally, L-NAME induces an increase in plasma levels of big endothelin-1 but not endothelin-1. Our results illustrate that blockade of either nitric oxide synthase or ET(B) receptors triggers a raise in plasma levels of endothelin-1 or its precursor. These later moieties are suggested to be significantly involved, through the activation of ET(A) receptors, in the pressor effects of L-NAME and BQ-788 in the anesthetized rabbit. PMID- 9369278 TI - Endothelin and prostaglandin H2 enhance arteriolar myogenic tone in hypertension. AB - We hypothesized that endothelin in addition to prostaglandin (PG)H2 may also contribute to the enhanced myogenic tone of skeletal muscle arterioles of spontaneously hypertensive (SH) rats. Changes in the diameter of isolated, cannulated arterioles (approximately 60 microm) from cremaster muscles of 30-week old normotensive Wistar Kyoto (WKY) and SH rats were measured as a function of perfusion pressure (20 to 140 mm Hg). Pressure-induced constrictions were significantly enhanced between 60 to 140 mm Hg in arterioles of SH rats compared with those of WKY rats; at 80 and 140 mm Hg the normalized diameter of arterioles (expressed as a percentage of corresponding passive diameter) of SH rats was 11.0% and 15.4% less (P<.05) than that of WKY rats. After inhibition of thromboxane A2-PGH2 receptors by SQ 29,548 (10[-6] mol/L), the still enhanced myogenic response of SH arterioles was eliminated by the removal of endothelium or the administration of BQ-123 (10[-7] mol/L), an endothelin A (ET-A) receptor blocker, which also inhibited constrictions to exogenous ET-1 (10[-11] to 5x10[ 10] mol/L). ET-1 elicited comparable responses in arterioles of SH and WKY rats. Thus, in SH rats the enhanced arteriolar constriction to increases in intravascular pressure seems to be due to the production of endothelium-derived constrictor factors PGH2 and endothelin. PMID- 9369279 TI - Sensitivity of blood pressure and renin activation during sodium restriction. AB - The objective of the present study was to explore the interrelationships among cumulative sodium loss, renin activation, and blood pressure changes during sodium restriction in essential hypertensive patients. Specifically, we wanted to know whether the degree of sodium sensitivity of blood pressure depends on renin activation during steady state or on initial renin activation during the first days of sodium restriction. Sixty-seven untreated essential hypertensive patients were admitted to a metabolic ward for 8 days and put on a sodium restricted diet of 55 mmol/d from the second to the last day. Urinary excretions of sodium, potassium, and creatinine were determined along with mean arterial pressure and weight during 7 days. Besides measurements in steady state condition (after 7 days), active plasma renin concentration, aldosterone, and catecholamines were also assessed during the first 3 days of sodium restriction. Analyzable data are available for 55 patients. Baseline sodium excretion and the activation of renin during the first 3 days both appeared to be predictors of total sodium loss after 7 days. Changes in blood pressure were not related to changes in sodium balance, but they were to baseline blood pressure, baseline norepinephrine, and renin activation during the early phase of sodium restriction. In addition, blood pressure appeared to fall more when the normal relationship between sodium loss and early (but not late) activation of renin was disturbed. We conclude that sodium sensitivity of blood pressure during sodium restriction is associated with a relative unresponsiveness of the renin system during the early phase of sodium loss rather than to absolute renin levels during steady state. PMID- 9369280 TI - Calcium signaling mechanisms in renal vascular responses to vasopressin in genetic hypertension. AB - Previous blood flow studies demonstrated that arginine vasopressin (AVP) produces exaggerated renal vasoconstriction in young spontaneously hypertensive rats (SHR) compared with Wistar-Kyoto control rats (WKY). The purpose of the present study was to determine the role of postreceptor calcium signaling pathways in AVP induced renal vasoconstriction in vivo. Renal blood flow (RBF) was measured by electromagnetic flowmetry in anesthetized, water-loaded, 8-week-old WKY and SHR pretreated with indomethacin to avoid interactions with prostaglandins. AVP was injected into the renal artery to produce a transient 25% to 30% decrease in RBF without affecting arterial pressure. To achieve similar control levels of vasoconstriction, SHR received a lower dose (2 versus 5 ng). Coadministration of nifedipine with AVP produced dose-dependent inhibition of the AVP-induced renal vasoconstriction. Nifedipine exerted maximum inhibition by blocking 30% to 35% of the peak AVP response, indicating the involvement of dihydropyridine-sensitive voltage-dependent calcium channels. To evaluate intracellular calcium mobilization, 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (TMB-8) or heparin was coadministered with AVP. Each agent produced a dose-dependent inhibition of up to 65% of the maximum blood flow change produced by AVP. The degrees of inhibition produced by maximum effective doses of nifedipine and TMB-8 were additive; the combination blocked up to 85% of the response to AVP. These observations indicate that about one third of the AVP-induced constriction of renal resistance vessels is mediated by voltage-dependent L-type calcium channels responsive to the dihydropyridine nifedipine. Approximately two thirds of the change in vascular tone is due to inositol 1,4,5-trisphosphate-mediated calcium mobilization from intracellular sources sensitive to TMB-8 and heparin. The results suggest that the exaggerated renal vascular reactivity to AVP challenge in SHR is probably not due to a strain difference in postreceptor calcium signal transduction. After AVP receptor stimulation, calcium mobilization and calcium entry signaling pathways participate to similar degrees in WKY and SHR. PMID- 9369281 TI - Perindopril ameliorates glomerular and renal tubulointerstitial injury in the SHR/N-corpulent rat. AB - We compared the effects of long-term treatment with the angiotensin-converting enzyme inhibitor perindopril and triple therapy (hydrochlorothiazide, reserpine, and hydralazine) on the metabolic and renal features in the SHR/N-corpulent (cp) rat, a genetic model of non-insulin-dependent diabetes mellitus and hypertension. Obese male SHR/N-cp rats (4 to 6 weeks old) were fed a 54% carbohydrate diet containing 18% sucrose and 36% starch. After 2 months on the diet, rats were assigned to one of three groups: one group (n=8) received perindopril (PE); the second group (n=8) received triple therapy (TT); and the third group (n=8) did not receive therapy. Treatment was maintained for 3 to 4 months. Body weight, food intake, and fasting levels of serum glucose and insulin did not differ among the three groups. Control rats exhibited progressive proteinuria in parallel with the rise in systolic blood pressure (SBP). Both PE and TT equally lowered SBP to normal levels and reduced proteinuria in treated rats. However, the reduction of proteinuria was greater and more sustained with PE than with TT (P<.05), whereas the effect of TT on proteinuria was delayed. Plasma renin activity was increased in PE and TT rats compared with control rats (P<.02). Semiquantitative analysis of renal lesions showed that the percentage of glomeruli with mesangial expansion and sclerosis and the tubulointerstitial score (an index of severity of tubulointerstitial lesions, namely tubular atrophy, inflammatory cellular infiltrates, and interstitial fibrosis) was reduced in both PE and TT rats. However, the reduction of glomerulosclerosis and tubulointerstitial lesions was greater in PE than in TT rats (P<.01). The percentage of glomerular sclerosis was positively correlated with the severity score of tubulointerstitial lesions (r=.60, P<.01). We conclude that PE is more effective than TT in halting the progression of proteinuria in the SHR/N-cp rat with non-insulin-dependent diabetes mellitus and hypertension. The antiproteinuric effect of PE is associated with significant reduction in glomerulosclerosis and tubulointerstitial lesions, independent of the effect of treating hypertension. PMID- 9369282 TI - Expression of the subtype 2 angiotensin (AT2) receptor protein in rat kidney. AB - In situ hybridization studies have suggested that the subtype 2 angiotensin (AT2) receptor gene is expressed in fetal and newborn rat kidney but is undetectable in the adult animals. In the present study, we investigated the expression of AT2 receptor protein in the fetal (days 14 and 19 of fetal life), newborn (day 1 postpartum), and adult (4-week-old and 3-month-old) rat kidney. Polyclonal anti peptide antiserum was raised against the amino terminus of the native AT2 receptor. The selectivity of the antiserum was validated by recognition of the AT2 receptor in a stably transfected COS-7 cell line by Western blot and immunocytochemical analysis. As a positive control, the AT2 receptor signal was detected strongly in the adrenal gland. Positive immunohistochemical staining was observed in the mesenchymal cells and ureteric buds of the 14-day fetal kidney and in the glomeruli, tubules, and vessels in the 19-day fetal and newborn kidney. Glomeruli expressing the AT2 receptor were localized mainly in the outer layer of the renal cortex. In the young (4-week-old) and mature (3-month-old) adult rat on normal sodium intake, renal AT2 receptor immunoreactivity was present in glomeruli but substantially diminished compared with that of newborn rats. In both young and mature adult rats, dietary sodium depletion increased the renal AT2 receptor signal, mainly in the glomeruli and interstitial cells. Preimmune and preadsorption controls were negative. Western blot analysis detected a single 44-kD band in the fetal and newborn rat kidney and in the young and mature adult rat kidney. Dietary sodium depletion increased the density of the AT2 receptor band in mature adult rat kidneys. These data provide evidence that the AT2 receptor protein is expressed in the fetal and newborn rat kidney, diminishes in adult life, and is reexpressed in the adult in response to sodium depletion. PMID- 9369283 TI - Angiotensin II has depressor effects in pregnant and nonpregnant women. AB - Studies in anesthetized animals suggest that angiotensin II evokes a depressor as well as a pressor effect, which becomes evident on cessation of infusion. We have studied 18 nonpregnant and 8, 23, and 22 women in the first, second, and third trimesters of pregnancy to determine whether such an effect is present in conscious women, whether it is dose dependent, and whether it is influenced by pregnancy. Angiotensin II was infused intravenously in doubling concentrations at 10-minute intervals until a pressor effect of approximately 20 mm Hg was observed. The infusion was stopped, and blood pressure was monitored at 2-minute intervals for 30 minutes. There was a significant diastolic depressor effect after stopping angiotensin II in the nonpregnant women and those in the second and third trimesters of pregnancy. Individual women required differing doses of angiotensin II to evoke the standardized pressor response. It was thus possible to examine the depressor response in each group in relation to infused doses of angiotensin II. In nonpregnant women and in those in the second and third trimesters of pregnancy, the depressor response was dose dependent (P<.001). At any given dose, the depressor response deepened as pregnancy progressed (P<.001). Basal plasma prostacyclin concentrations rise in pregnancy, and angiotensin II can stimulate prostacyclin synthesis. This might mediate the depressor effect. In conclusion, the diminished pressor response to angiotensin II in normal pregnancy may be partly due to an increasing depressor effect of the hormone. PMID- 9369284 TI - Cardiac type-1 angiotensin II receptor status in deoxycorticosterone acetate-salt hypertension in rats. AB - The regulation of angiotensin II (Ang II) receptors and Ang II-induced modulation of intracellular Ca2+ concentration in cardiac cells from hearts of experimentally induced hypertensive deoxycorticosterone acetate (DOCA)-salt and control unilaterally nephrectomized (Uni-Nx) Sprague-Dawley rats was assessed. Ang II receptor density and intracellular Ca2+ concentration measurements were examined in adult ventricular myocytes and fibroblasts by radioligand binding assay and digital imaging using fura 2 methodology, respectively. Four-week DOCA salt treatment induced hypertension associated with cardiac hypertrophy. Ang II binding studies demonstrated that adult ventricular myocytes and fibroblasts possess mainly the AT1 subtype receptor. Moreover, DOCA-salt hypertension was associated with a 1.8-fold increase in Ang II-specific binding compared with myocytes from Uni-Nx control rats. Intracellular Ca2+ responses induced by increasing Ang II concentrations (10[-12] to 10[-4] mol/L) were significantly enhanced in cardiomyocytes from DOCA-salt rats. The effects of Ang II on intracellular Ca2+ spike frequency were unaltered in cardiomyocytes from DOCA salt-hypertensive rats. The density of AT1 subtype receptors was not modified in ventricular fibroblasts after DOCA-salt treatment. Ang II increased intracellular Ca2+ concentration similarly in ventricular fibroblasts from normal and hypertensive rats. In conclusion, DOCA-salt hypertension is characterized by an increased AT1 receptor density and intracellular calcium responses in ventricular myocytes, whereas in ventricular fibroblasts the AT1 receptor status is unaltered. These findings report for the first time the cardiac cell-specific implication of Ang II and the intracellular calcium signaling pathway stimulated by the AT1 receptor in cardiac hypertrophy in DOCA-salt-hypertensive rats. PMID- 9369285 TI - Analysis of the effects of candesartan in the mesenteric vascular bed of the cat. AB - The effects of the nonpeptide angiotensin II AT1 receptor antagonist candesartan on responses to angiotensin II were investigated in the mesenteric vascular bed of the cat. Under constant-flow conditions, injections of angiotensin II caused dose-related increases in perfusion pressure that were reduced by candesartan in doses of 3, 10, and 30 microg/kg i.v.. After administration of the AT1 receptor antagonist in a dose of 3 microg/kg i.v., the dose-response curve for angiotensin II was shifted to the right in a parallel manner, whereas the administration of higher doses resulted in nonparallel rightward shifts of the angiotensin II dose response curves. The duration of the inhibitory actions of candesartan were dependent on dose, and the AT1 receptor antagonist did not alter responses to norepinephrine, U46619, vasopressin, neuropeptide Y, BAY K8644, endothelin-1, alpha,beta-methylene ATP, adenosine, acetylcholine, and bradykinin. Treatment with the AT2 receptor antagonist PD123,319 or with sodium meclofenamate did not alter the inhibitory effects of candesartan on responses to angiotensin II. Candesartan also decreased pressor responses to angiotensin III and IV with a parallel shift at the low dose and a nonparallel shift to the right of the dose response curve at the high dose. These results indicate that candesartan is a potent, selective, long-acting AT1 receptor antagonist that, depending on dose, can produce both competitive and noncompetitive blockade of responses to angiotensin II, III, and IV. PMID- 9369287 TI - Impaired cortisol binding to glucocorticoid receptors in hypertensive patients. AB - We compared glucocorticoid receptor binding characteristics and glucocorticoid responsiveness of human mononuclear leukocytes (HML) from hypertensive patients and matched normotensive volunteers. We also considered associations of these variables with plasma renin activity, aldosterone, cortisol, corticotropin, and electrolyte concentrations. We calculated binding affinity (Kd; nmol/L) and capacity (Bmax; sites/cell) for dexamethasone and cortisol from homologous and heterologous competition curves for specific [3H]dexamethasone binding sites on HML isolated from the blood of normotensive volunteers and subjects with essential hypertension. Glucocorticoid responsiveness of HML was evaluated as IC50 values (nmol/L) for dexamethasone and cortisol for the inhibition of lysozyme release. We measured plasma hormones by radioimmunoassay. Kd values (mean+/-SE) for cortisol in HML of hypertensive patients were higher than in control subjects (24.6+/-2.4 versus 17.5+/-1.7 nmol/L, P<.04). Binding capacity (4978+/-391 versus 4131+/-321 sites/cell), Kd values for dexamethasone (6.7+/-0.5 versus 5.7+/-0.3 nmol/L), and IC50 values for dexamethasone (3.4+/-0.3 versus 3.1+/-0.2 nmol/L) and cortisol (12.2+/-1.6 versus 9.5+/-0.3 nmol/L) were not significantly different. Patients with renin values less than 0.13 ng angiotensin I/L per second were markedly less sensitive to cortisol than those with higher values. Both Kd (30.3+/-2.5 versus 19.2+/-2.4 nmol/L) and IC50 values (15.5+/-1.8 versus 8.9+/-1.2 nmol/L) for cortisol were significantly higher in patients with lower renin values (P<.03). Other variables, including plasma hormone and electrolyte values and binding characteristics for dexamethasone, were not different. These data suggest that cortisol binding to glucocorticoid receptor is slightly impaired in patients with essential hypertension. In vivo, this could lead to inappropriate binding of cortisol to mineralocorticoid receptors. Hence, decreased sensitivity to cortisol is associated with renin suppression. This hypothesis is supported by evidence of hypertension and low renin activity, which others have described in patients with primary glucocorticoid resistance due to mutations of the glucocorticoid receptor. PMID- 9369286 TI - Relationship of tachycardia with high blood pressure and metabolic abnormalities: a study with mixture analysis in three populations. AB - Faster resting heart rate has been shown to be associated with a higher risk of developing hypertension and a greater incidence of cardiovascular morbidity and mortality. The aim of this study was to investigate the distribution of heart rate and its relationship with blood pressure and other cardiovascular risk factors in three populations. One European general population (Belgian study), one North American general population (Tecumseh study), and one European hypertensive population (HARVEST trial) were studied. Within each population, mixture analysis was used to investigate whether a mixture of two normal distributions explained the variance in heart rate better than a single distribution. In the men of all populations, mixture analysis identified a larger subpopulation of subjects with normal heart rate and a smaller one with fast heart rate. The subgroups with tachycardia had higher blood pressure and lipid levels than those with normal heart rate. In the populations in which they were measured, fasting insulin and postload glucose were also higher in the men with faster heart rate. A subgroup with tachycardia could also be singled out among the women from Tecumseh, but no relation between heart rate and blood pressure could be found. These findings show that in Western societies, high heart rate pertains to a distinct subgroup of subjects, who are more frequently men and exhibit the characteristic features of the insulin resistance syndrome. Sympathetic overactivity is likely to be the mechanism underlying this clinical condition. PMID- 9369288 TI - Susceptibility to pain in hypertensive and normotensive patients with coronary artery disease: response to dental pulp stimulation. AB - An association between a decreased responsiveness to varying painful stimuli and arterial hypertension both in animals and in humans has been documented. The relationship between essential hypertension and silent myocardial ischemia in coronary artery disease (CAD) populations is not well understood. The aims of this study in CAD patients with and without essential hypertension were (1) to determine dental pain threshold and reaction to tooth pulp stimulation and (2) to ascertain whether hypertensive CAD patients differ from normotensive ones in reactivity to pain. This study involved 182 patients who were affected by mild and moderate hypertension (G1) and 174 normotensive patients (G2). The inclusion criteria were reproducible exercise-induced myocardial ischemia, CAD documented at angiography, and dental formula suitable for pulp test. All patients underwent an ergometric stress test, coronary angiography, and pulp test. Our CAD hypertensive patients showed a lower prevalence of angina during daily life (64.8% in G1 versus 81.6% in G2, P<.05) and a higher incidence of exercise induced silent myocardial ischemia (60.4% in G1 versus 48.8% in G2, P<.05) than the normotensive group. The mean anginal pain intensity, which was suffered both during spontaneous transitory episodes of ischemia and/or during acute myocardial infarction, was significantly lower in G1 than in G2 patients (P<.05). During pulp test, 31.8% of G1 and 13.7% of G2 referred no symptoms, even at the highest current intensity of 500 mA. The hypertensive patients with symptoms during pulp test had a higher mean dental pain threshold and lower mean threshold reaction and maximal reaction than did the normotensive symptomatic ones. In patients of both groups, a positive correlation between the mean maximal reaction during pulp test and the prevalence of angina during daily life was also found. In conclusion, patients with CAD and essential hypertension differ from normotensive CAD patients in reactivity to pain. Significantly higher pain thresholds and lower reactions to tooth pulp stimulation characterized patients with increased blood pressure values. PMID- 9369289 TI - Increased expression of parathyroid hormone-related peptide gene in blood vessels of spontaneously hypertensive rats. AB - We have shown recently that mechanical stretch of cultured rat aortic smooth muscle cells induces a marked increase in gene expression of the vasorelaxant parathyroid hormone-related peptide. In the present study, we investigated whether mechanical force affected the in vivo parathyroid hormone-related peptide gene expression in blood vessels. Northern blot analysis revealed that stretch of isolated rat aortic strips increased the expression level of parathyroid hormone related peptide mRNA. The parathyroid hormone-related peptide transcript level in aorta and mesenteric vessels from 18-week-old spontaneously hypertensive rats (SHR) was 2.5- and 2.2-fold higher, respectively, compared with age-matched Wistar-Kyoto (WKY) controls, whereas the parathyroid hormone-related peptide mRNA level in aorta from normotensive 4-week-old SHR was similar to that of age matched WKY controls. The aortic parathyroid hormone-related peptide content was higher in 18-week-old SHR than in age-matched WKY controls. Moreover, treatment of mature SHR with an angiotensin II type 1 receptor antagonist or hydralazine caused a concomitant decrease in the parathyroid hormone-related peptide transcript level in aorta with lowering of blood pressure. These results suggest that the in vivo parathyroid hormone-related peptide gene expression in blood vessels is under the control of mechanical force, pointing to a role of parathyroid hormone-related peptide in the regulation of vascular tone. PMID- 9369291 TI - Nocturnal blood pressure fall. PMID- 9369290 TI - Association of calcitriol and blood pressure in normotensive men. AB - The purpose of this study was to clarify the possible associations between the serum 1,25-dihydroxyvitamin D (calcitriol) level and blood pressure. Cross sectional analysis of data was performed. Data collected included levels of serum calcitriol, parathyroid hormone, serum calcium, and blood lead; blood pressure; dietary history; and demographic and anthropometric variables. One hundred normotensive male industrial employees made up the study population. Systolic blood pressure and diastolic blood pressure were main outcome measures. After possible confounders were controlled for, multivariate analyses yielded an inverse, independent, and statistically significant association between calcitriol level and systolic blood pressure (standardized beta= -0.2704, P=.0051). A similar trend of borderline significance was found for the association between calcitriol and diastolic blood pressure (standardized beta= 0.1814, P=.0611). Parathyroid hormone, serum calcium, and blood lead levels were not associated with blood pressure. When subjects were divided into four groups by calcitriol level, those in the lowest quartile showed significantly higher systolic and diastolic blood pressures than those in the upper quartile (difference=11 mmHg, P=.007, and difference=4 mmHg, P=.071, respectively). There is an inverse association between serum calcitriol level and blood pressure. This suggests that in addition to its role in calcium homeostasis, the active metabolite of vitamin D may play a role in determining blood pressure. The differences in both systolic and diastolic blood pressures between the upper and lower quartiles of serum calcitriol were substantial and may be of clinical significance. PMID- 9369292 TI - Sodium pump isoform specificity for digitalis-like factor. PMID- 9369293 TI - LVH in primary aldosteronism. PMID- 9369294 TI - Nestin expression in reactive astrocytes following focal cerebral ischemia in rats. AB - During central nervous system (CNS) development, intermediate filaments are subjected to a sequential remodelling process. Nestin is a distinct intermediate filament which is transiently expressed in proliferating neuroepithelial stem cells during the neurulation stage of development. Nestin re-expression in the adult rat was studied following transient (2 h) middle cerebral artery occlusion. Seven days after the ischemic insult, nestin reactive astrocytes were found in the border zone surrounding cerebral infarction. Nestin immunoreactivity delineated a zone between infarction and the surrounding intact cerebral parenchyma. In situ hybridization for nestin mRNA showed early changes in small cells in the surround of the ischemic lesion. These results with nestin, along with other stem cell markers expressed by reactive astrocytes, suggest an embryonic reversion of the mature cytoskeleton as a response of astrocytes to cerebral injury. PMID- 9369295 TI - F-actin cytoskeleton and sucrose permeability of immortalised rat brain microvascular endothelial cell monolayers: effects of cyclic AMP and astrocytic factors. AB - The immortalised RBE4 cell line, derived from rat brain capillary endothelial cells, preserves many features of the in vivo brain endothelium, and hence is of interest as a potential in vitro model of the blood-brain barrier (BBB). This study reports the effects of elevated intracellular cAMP and factors released by astrocytes on the F-actin cytoskeleton and paracellular sucrose permeability of monolayers of RBE4 cells. RBE4 cells grown in control medium showed a marked increase in the F-actin staining at the cytoplasmic margin at confluence, which was not significantly enhanced by elevation of intracellular cAMP and/or addition of astrocyte-conditioned medium (ACM). The formation of the marginal band of F actin was accompanied by an increase in the F-actin content of the RBE4 cells up to confluence, and a decline in F-actin content thereafter. Elevation of intracellular cAMP or co-culture above astrocytes significantly decreased the paracellular sucrose permeability of confluent RBE4 cell monolayers grown on collagen filters (P < 0.01 and P < 0.001, respectively). Co-culture above astrocytes together with elevated cAMP also produced a significant decrease in the sucrose permeability of the monolayer (P < 0.01) but this was no greater than with astrocytes alone. These findings show that the RBE4 cell line may serve as a useful in vitro model for the study of brain endothelial cell physiology and agents which alter the permeability of the BBB. PMID- 9369297 TI - Sex differences in N-methyl-D-aspartate involvement in kappa opioid and non opioid predator-induced analgesia in mice. AB - There are suggestions of sex differences in N-methyl-D-aspartate (NMDA) receptor system involvement in the mediation of analgesia. The present study examined the effects of the specific, competitive NMDA antagonist, NPC 12626, on the nociceptive (50 degrees C hot plate) responses of reproductive male and female laboratory mice exposed to (i) an ethologically relevant aversive stimulus, the odor of a predator and (ii) administration of the kappa opiate agonist, U69,593. A 30-s exposure to 2-propylithietane, the major component of weasel odor, elicited a 'non-opioid' analgesia that was in both sexes insensitive to naloxone and the kappa opiate antagonist nor-binaltorphimine. In male mice this non-opioid analgesia was antagonized by NPC 1262, while in reproductive females the predator induced analgesia was insensitive to NPC 12626. Similarly, NPC 12626 attenuated the analgesic effects of the kappa opiate agonist, U69,593, in male mice while having no significant effects on the equivalent levels of kappa opiate analgesia in females. These results show that there are sex differences in NMDA involvement in the expression and, or mediation of both non-opioid stress-induced and kappa opiate-mediated analgesia. PMID- 9369296 TI - Application of recombinant adenovirus for in vivo gene delivery to spinal cord. AB - One strategy for treating spinal cord injury is to supply damaged neurons with the appropriate neurotrophins either by direct delivery or by transfer of the corresponding genes using viral vectors. Here we report the feasibility of using recombinant adenovirus for in vivo gene transfer in spinal cord. After injection of a recombinant adenovirus carrying a beta-galactosidase (beta-gal) reporter gene into the mid-thoracic spinal cord of adult rats, transgene expression occurred not only in several types of cells around the injection site but also in neurons whose axons project to this region from rostral or caudal to the injection site. Among labeled neurons were those of the red nucleus, the vestibular nuclei, reticular formation, locus coeruleus, and Clarke's nucleus. A non-specific immune reaction, which could be blocked by immunosuppression with Cyclosporin A, reduced the number of transduced cells surviving at the injection site by 1 month. In neurons away from the injection site, where the immune response was minimal, transgene expression lasted for at least 2 months. These results support the idea that recombinant adenovirus can be used in the spinal cord for in vivo delivery of therapeutic genes important for supporting neuron survival and axon regeneration. PMID- 9369298 TI - Effects of the removal of extracellular Ca2+ on [Ca2+]i responses to FCCP and acetate in carotid body glomus cells of adult rabbits. AB - The effects of the removal of extracellular Ca2+ on the responses of cytosolic concentrations of Ca2+ ([Ca2+]i) to acidic stimuli, a protonophore carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) and an organic acid acetate, were examined in clusters of cultured carotid body glomus cells of adult rabbits using fura-2 microfluorometry. Application of FCCP (1 microM) induced an increase in [Ca2+]i (mean +/- S.E.M., 108 +/- 14%). After withdrawal of the protonophore the increased [Ca2+]i returned slowly to a resting level. The [Ca2+]i response was attenuated by an inorganic Ca2+ channel antagonist Ni2+ (2 mM) by 81 +/- 4%, and by an L-type voltage-gated Ca2+ channel antagonist D600 (10 microM) by 53 +/- 13%. The removal of extracellular Ca2+ eliminated the [Ca2+]i response in 71% of the tested cells (n = 17), and depressed it by 68 +/- 6% in the rest. Recovery following stimulation with FCCP in the absence of Ca2+ reversibly produced a rapid and large rise in [Ca2+]i, referred to as a [Ca2+]i rise after Ca2+ free/FCCP. The magnitude of a [Ca2+]i rise after Ca2+-free/FCCP (285 +/- 28%, P < 0.05) was larger than that of an increase in [Ca2+]i induced by FCCP in the presence of Ca2+ and had a correlation with the intensity of the suppression of the [Ca2+]i response by Ca2+ removal. A [Ca2+]i rise after Ca2+-free/FCCP was inhibited mostly by D600. Similarly, recovery following exposure to acetate in the absence of Ca2+ caused a rise in [Ca2+]i, referred to as a [Ca2+]i rise after Ca2+-free/acetate which was sensitive to D600. The magnitude of the [Ca2+]i rise was larger than that of a change in [Ca2+]i caused by acetate in the presence of Ca2+. These results suggest that FCCP-induced increase in [Ca2+]i was, in most cells, due to Ca2+ influx via L-type voltage-gated Ca2+ channels and, in some cells, due to both Ca2+ influx and Ca2+ release from internal Ca2+ pool. The removal of extracellular Ca2+ might modify [Ca2+]i responses to acidic stimuli, causing [Ca2+]i rises after Ca2+-free/acidic stimuli which involve mostly L-type Ca2+ channels. PMID- 9369299 TI - Mobilization of arachidonate and docosahexaenoate by stimulation of the 5-HT2A receptor in rat C6 glioma cells. AB - In this study, we demonstrate that astroglial 5-HT2A receptors are linked to the mobilization of polyunsaturated fatty acids (PUFA). Stimulation of C6 glioma cells, prelabeled with [3H]arachidonate (AA, 20:4n6) and [14C]docosahexaenoate (DHA, 22:6n3), with serotonin and the 5-HT(2A/2C) receptor agonist (+/-)-2,5 dimethoxy-4-iodoamphetamine hydrochloride (DOI) resulted in the mobilization of both [3H] and [14C] into the supernatant of the cell monolayers. The increased radioactivity in the supernatant was mainly associated with free fatty acids. Experiments using inhibitors of phosphoinositide-specific phospholipase C and PLA2, inhibited the DOI-stimulated mobilization of AA and DHA, suggesting the involvement of both phospholipases. Ketanserin (1 microM), a 5-HT(2A/2C) receptor antagonist, and MDL 100,907 (R(+)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4 fluorophenylethyl)]-4-pi peridine-methanol) (1 microM), a highly selective antagonist for 5-HT2A receptors, significantly decreased the DOI-stimulated release of AA and DHA. These results indicate that the 5-HT2A receptor is coupled to the mobilization of PUFA. The release of AA and DHA in response to serotonin may represent a mechanism through which astroglia provide these polyunsaturated fatty acids to neurons. PMID- 9369300 TI - 3-[2,4-Dimethoxybenzylidene]anabaseine (DMXB) selectively activates rat alpha7 receptors and improves memory-related behaviors in a mecamylamine-sensitive manner. AB - The alpha7 nicotinic receptor agonist 3-[2,4-dimethoxybenzylidene]anabaseine (DMXB; GTS-21) was investigated for its ability to: (1) activate a variety of nicotinic receptor subtypes in Xenopus oocytes; (2) improve passive avoidance and spatial Morris water task performances in mecamylamine-sensitive manners in bilaterally nucleus basalis lesioned rats; and (3) elevate high-affinity [3H]acetylcholine (ACh) and high-affinity alpha-[125I]bungarotoxin binding in rat neocortex following 2 weeks of daily injections. DMXB (100 microM) activated alpha7 homo-oligomeric receptors, without significant activity at alpha2-, alpha3 and alpha4-containing subtypes. Mecamylamine blocked rat alpha7 receptors weakly if co-administered with agonist, but much more potently when pre-applied. Bilateral ibotenic acid lesions of the nucleus basalis interfered with passive avoidance and spatial memory-related behaviors. DMXB (0.5 mg/kg, i.p.) improved passive avoidance behavior in lesioned animals in a mecamylamine-sensitive manner. DMXB (0.5 mg/kg 15 min before each session) also improved performance in the training and probe components of the Morris water task. DMXB-induced improvement in the probe component but not the training phase was mecamylamine sensitive. [3H]ACh binding was elevated after 14 days of daily i.p. injections with 0.2 mg/kg nicotine but not after 1 mg/kg DMXB. Neither drug elevated high affinity alpha-[125I]bungarorotoxin binding over this interval. PMID- 9369301 TI - Glutamate stimulates 2-deoxyglucose uptake in rat cerebellar granule cells. AB - Although glutamate is the most widely used excitatory neurotransmitter in mammalian brain a prolonged exposure of neurons to this amino acid causes their degeneration and death, an event also referred to as excitotoxicity. Since one of the earliest events of excitotoxicity is an impairment of energy metabolism, we have assessed whether such damage is due to a concomitant alteration of glucose uptake in rat cerebellar granule cells. We report that glutamate rather than inhibiting actually activates glucose uptake in a time- and temperature-dependent fashion and that this effect is completely blocked by MK-801, a specific inhibitor of glutamate receptors of the NMDA type. Moreover, while the rate of glucose uptake is constant between 2 DIV and 10 DIV, the extent of glutamate triggered increase above the basal level is undetectable at 2 DIV and becomes progressively higher with days of incubation in cultures, in a fashion overlapping the appearance of functionally active glutamate receptors. The action of this excitatory amino acid is also mimicked, to various extents, by other glutamate agonists such as kainate, NMDA and quisqualate. The glutamate stimulation of glucose uptake occurs in the same range of concentrations as those necessary to cause neuronal death. These findings are discussed in the light of the possible metabolic mechanism responsible of such activation and in connection with previous similar studies performed on glial or mixed glial-neuronal cultures, whereby the stimulating action of glutamate is achieved via alternate pathways not involving glutamate receptors. PMID- 9369302 TI - Melatonin suppression of PC12 cell growth and death. AB - Melatonin has previously been reported to influence cell differentiation and growth in a number of cell culture systems in vitro. In this paper, we describe the effects of high pharmacological and low physiological concentrations of melatonin on cell growth in rat pheochromocytoma cells (PC12 cells). Melatonin produced a biphasic response with respect to cell growth in PC12 cells. At low concentrations (1-10 nM) melatonin suppressed PC12 cell growth whereas at higher concentration (10 microM) it prevented cell death. Cultures treated with high concentrations of melatonin displayed an increase in cell number and a decreased release of lactic acid dehydrogenase (LDH) into the culture media, indicating that melatonin was enhancing cell survival as opposed to stimulating cell proliferation. Inhibition of cell death by high concentrations of melatonin was both time and concentration-dependent and did not require the continued presence of melatonin throughout the entire time of incubation. These studies suggest melatonin is preventing either apoptosis or programmed cell death. In contrast, concentrations of melatonin (1-10 nM) at or near the binding affinity for the nuclear receptor, RZRbeta, suppressed PC12 cell growth. At these concentrations, melatonin failed to inhibit forskolin-induced cAMP formation and process outgrowth as well as prevent forskolin suppression of cell growth. These data indicate that PC12 cells probably lack functionally active cell surface receptors for melatonin and suggest the interaction of melatonin with the nuclear receptor may be responsible for suppression of PC12 cell growth. PMID- 9369303 TI - Role of respiratory and non-respiratory neurones in the region of the NTS in the elaboration of the sneeze reflex in cat. AB - Extracellular recordings were made in the dorsal respiratory group (DRG) and adjacent reticular formation following single-shock stimulation of the anterior ethmoidal nerve (AEN) and during sneeze evoked by repetitive stimulation of the AEN in nembutal-anaesthetized, curarized and ventilated cats. These neurones were characterised according to (i) their activity during the respiratory cycle (as inspiratory augmenting or decrementing (I Aug or I Dec), expiratory augmenting or decrementing (E Aug or E Dec), silent or tonic), and (ii) their axonal projection (bulbospinal or non-bulbospinal-non-vagal (BS or NBS-NV)). Following single-shock stimulation of the AEN, most of the inspiratory neurones were transiently inhibited, whereas E Aug neurones were activated and E Dec neurones were activated and then inhibited. Silent neurones responded with a multispike or a paucispike pattern. Following repetitive stimulation of the AEN and during the resulting sneeze reflex, I Aug neurones increased their activity in parallel with the phrenic activity, I Dec neurones fired at the onset and at the end of the inspiration, E Dec and some silent neurones fired either during the compressive phase or after the expulsive phase, whereas E Aug and some silent neurones fired during the expulsive phase. We conclude that sneeze involves a reconfiguration of the central respiratory drive which uses, at least partly, the respiratory network to trigger a non-ventilatory defensive motor act. PMID- 9369304 TI - Reduction in the ratio of beta-preprotachykinin to preproenkephalin messenger RNA expression in postmortem human putamen during aging and in patients with status lacunaris. Implications for the susceptibility to parkinsonism. AB - Gamma-aminobutyric acid (GABA)/substance P (SP) neurons and GABA/enkephalin (Enk) neurons in the striatum exert opposing influence on the regulation of movement. The loss of GABA/SP neurons results in hypokinetic disorders (parkinsonism), whereas the loss of GABA/Enk neurons results in hyperkinetic disorders (e.g. chorea). The present study determined age-related changes in the beta preprotachykinin (the precursor of SP) and preproenkaphalin (the precursor of Enk) messenger RNA (mRNA) ratio in the postmortem human putamen using the reverse transcription-polymerase chain reaction (RT-PCR). The ratio of beta preprotachykinin to preproenkephalin mRNA expression decreased with age. The reduction in the beta-preprotachykinin/preproenkephalin mRNA ratio was more marked in cases with multiple small infarcts (status lacunaris) in the putamen. These findings may in part explain the susceptibility of the elderly, particularly of those with ischemic changes in the striatum to hypokinetic disorders. PMID- 9369305 TI - A role for hydrolysis of inositol 1,4,5-trisphosphate in terminating the response to inositol 1,4,5-trisphosphate and to a flash of light in Limulus ventral photoreceptors. AB - Injection of inositol 1,4,5-trisphosphate (Ins 1,4,5-P3) into Limulus ventral photoreceptors produces excitation similar to that produced by light. One process which might contribute to rapid termination of the responses to Ins 1,4,5-P3 and to light is the hydrolysis of Ins 1,4,5-P3 by an InsP3-5-phosphatase to form inositol 1,4-bisphosphate. Inositol 2,4,5-trisphosphate (Ins 2,4,5-P3) is known to be less hydrolysable by the InsP3-5-phosphatase than is Ins 1,4,5-P3. Whereas ventral photoreceptors respond to an injection of Ins 1,4,5-P3 with a single wave of depolarization, the response to Ins 2,4,5-P3 is a burst of waves of depolarization. Our hypothesis is that it is the resistance to hydrolysis by the InsP3-5-phosphatase which accounts for the burst of waves produced by Ins 2,4,5 P3. To test this idea we injected ventral photoreceptors with Ins 1,4,5-P3 in the presence of the non-specific phosphatase inhibitors, vanadate and fluoride, which prolong the response to a flash of light in ventral photoreceptors (D.W. Corson, A. Fein, W.W. Walthall, J. Gen. Physiol. 82 (1983) 659-677). In the presence of fluoride or vanadate the response to Ins 1,4,5-P3 was composed of a burst of waves rather than a single wave of depolarization. We conclude that hydrolysis of Ins 1,4,5-P3 by the InsP3-5-phosphatase plays a role in terminating the ventral photoreceptors response to Ins 1,4,5-P3 and also to light. PMID- 9369306 TI - Neurons of the rostral para-ambiguual field have activity correlated to the 10-Hz rhythm in sympathetic nerve discharge of urethane-anesthetized cat. AB - Using the techniques of time domain correlation (mid-signal spike-triggered averaging) and frequency domain correlation (neuron-to-nerve coherence), 24% (54) of a sample of 229 neurons of the rostral para-ambiguual field have shown to have activity correlated to the 8- to 13-Hz rhythm in the inferior cardiac sympathetic nerve discharge (SND) of urethane-anesthetized cat. This correlation existed in both baroreceptor-innervated and -denervated animals. Of the correlated neurons, 37% (20) were non-rhythmically firing and displayed flat autospectra, while 63% (34) fired rhythmically and contained well-defined peaks in their autospectra. The group firing rate of these neurons was 4.3 +/- 0.4 spikes/s, indicating that they are not pacemaker neurons for the 10-Hz SND rhythm. The group time of firing of these neurons to the next peak of the SND slow wave was 52 +/- 4 ms. Correlation of the activity of medullary neurons with the 8-13-Hz rhythm of the SND was previously claimed only for rostral ventrolateral medulla, caudal raphe, and rostral caudal ventrolateral medulla. This present finding suggests that this behavior may be more widely spread throughout the medulla. PMID- 9369307 TI - The effect of blockade of kappa-opioid receptors in the medial preoptic area on the luteinizing hormone surge in the proestrous rat. AB - The present study examined whether blockade of kappa-opioid receptors in the medial preoptic area (MPOA) prior to the critical period on the afternoon of proestrus could prematurely evoke an ovulatory luteinizing hormone (LH) surge, and if so, whether norepinephrine (NE) is involved in mediating this response. In the first experiment, push-pull perfusion of the MPOA with nor-binaltorphimine (nor-BNI), a specific kappa-opioid receptor antagonist, was done in rats between 10.30 and 13.50 h on proestrus. To determine whether any resulting ovulation was due to a nor-BNI-induced increase in LH release, rats were injected with pentobarbital at 13.55 h to block the afternoon LH surge. In 7 of 10 rats, nor BNI in the MPOA produced a large increase in LH release beginning between 12.30 and 13.30 h, and 5 of 7 ovulated. During MPOA perfusion with cerebrospinal fluid in our normal colony between 14.00 and 17.00 h, surges of LH release began in the majority of rats between 15.30 and 16.30 h. Thus blockade of MPOA kappa-opioid receptors advanced the LH surge by 3 h. The next experiment examined the effect of NE synthesis inhibition with bis(4-methyl-1-homopiperazinylthiocarbonyl) disulfide (FLA-63), or alpha-adrenergic receptor blockade with phenoxybenzamine (PBZ), on the nor-BNI-induced LH response. In 5 of 6 vehicle-treated rats, blockade of MPOA kappa-opioid receptors elicited a large increase in LH release and all 5 ovulated. In contrast, only 3 of 8 rats pretreated with FLA-63 had a large increase in LH release and ovulated, and PBZ prevented the nor-BNI-induced LH increase and ovulation in 4 of 4 rats. PBZ also prevented the afternoon LH surge and ovulation in 4 of 4 rats in our normal colony. Finally, HPLC measurement of NE levels in MPOA push-pull perfusate indicated no increase in NE release during the nor-BNI-induced or normal afternoon LH surges. These results indicate that antagonism of kappa-opioid receptors in the MPOA can prematurely evoke an ovulatory LH surge prior to the critical period on the afternoon of proestrus. Furthermore, the nor-BNI-induced as well as the normal afternoon LH surges are dependent on the proper functioning of central noradrenergic neurons, but do not involve increased NE release within the MPOA. PMID- 9369308 TI - Melatonin protects primary cultures of rat cortical neurones from NMDA excitotoxicity and hypoxia/reoxygenation. AB - Studies on rat cortical cultures show that glutamate (10 microM) or hypoxia followed by reoxygenation causes damage to the cells as indexed by a release of lactate dehydrogenase (LDH). These effects could be counteracted by the N-methyl D-aspartate (NMDA) antagonist MK-801 (2 microM) but not by the kainate/AMPA antagonist CNQX (100 microM). These data favour the view that the damage caused to the cells by glutamate and hypoxia/reperfusion is mediated via NMDA receptors. The damage to the cells could also be prevented by melatonin (100 microM). The melatonin effect is not mediated by specific receptors because it was not blunted by the melatonin antagonist, luzindole. Moreover, NMDA stimulated an accumulation of 45Ca2+ by cortical neurones, but although this effect was counteracted by MK 801, melatonin was ineffective, which showed that the neuroprotective effect of melatonin is not elicited by direct action with NMDA receptors. Ascorbate and iron stimulated the production of free radicals in a retinal cell preparation. Chelation of the iron with deferoxamine prevented this process as did melatonin while MK-801 had no effect. The combined findings suggest that melatonin counteracts the in vitro destructive effects of NMDA or hypoxia/reperfusion by preventing accumulation of excessive free radicals. PMID- 9369309 TI - Serotonin-containing fibers in the suprachiasmatic hypothalamus attenuate light induced phase delays in mice. AB - Photic and non-photic stimuli phase shift and entrain circadian rhythms through distinct but interacting mechanisms which impinge on the suprachiasmatic nucleus (SCN), the circadian pacemaker. Our understanding of this mechanism is incomplete. Serotonin (5-HT) injected locally at the SCN reduces light-induced glutamate release and decreases the expression of c-fos, a marker of photic transduction. Furthermore, in SCN slices, 5-HT application reduces field potentials after optic nerve stimulation. We therefore predicted that 5-HT terminal destruction restricted to the SCN would augment phase shifts of circadian rhythms induced by light exposure. To investigate this possibility, we compared photic phase delays and Fos-like immunoreactivity in mice which had previously received bilateral infusions directed at the SCN containing either the selective 5-HT neurotoxin 5,7-dihydroxytryptamine (DHT, n = 16) or vehicle (VEH, n = 12). Phase delays after a light pulse given during the mid-subjective night (30 lux, 30 min starting at circadian time (CT) 12-20) in DHT-mice were 50% greater than in VEH-mice (P = 0.017). DHT mice (n = 5) had 76% larger Fos responses to a mid-subjective night light pulse than VEH-mice (n = 5) (P = 0.029). We conclude that 5-HT at or near the SCN in mice reduces photic phase shifts and modulates the magnitude of the photic phase response in the mouse. PMID- 9369310 TI - Differential expression of Fos protein after transection of the rat infraorbital nerve in the trigeminal nucleus caudalis. AB - To determine the effects of nerve injury on Fos expression, temporal and spatial distributions of Fos-positive neurons in the trigeminal nucleus caudalis were examined after tissue injury for isolation of the infraorbital nerve as controls and transection of this nerve as well as noxious chemical stimulation by formalin injection in adult rats. Fos immunoreactivity was markedly elevated in laminae I and II of the only ipsilateral nucleus caudalis 2 h after these surgical procedures and noxious chemical stimulation. The distributions of Fos-positive neurons were restricted rostro-caudally following formalin injection and tissue injury compared to transection of the infraorbital nerve. One day after tissue injury and nerve transection, however, Fos-positive neurons were distributed bilaterally in laminae III and IV extending rostro-caudally and medio-laterally in this nucleus, and this persisted over the 2-week study period. The number of Fos-positive neurons in the side ipsilateral to nerve transection was markedly less than that in the contralateral side whereas positive neurons in the tissue injured rats were distributed symmetrically along the rostro-caudal axis. There was no difference in the contralateral sides between nerve transection and tissue injury groups. The rostro-caudal level showing reduction in Fos expression corresponded roughly to the sites of central termination of the injured nerve in this nucleus, suggesting a role for the primary afferents in the reduction of Fos expression in laminae III and IV neurons of the ipsilateral nucleus caudalis. PMID- 9369311 TI - Vasopressin in the forebrain of common marmosets (Callithrix jacchus): studies with in situ hybridization, immunocytochemistry and receptor autoradiography. AB - The distribution of vasopressin (AVP) producing cells, their projections and AVP receptors was examined in the brain of common marmosets (Callithrix jacchus) using in situ hybridization, immunocytochemistry and receptor autoradiography. Clusters of cells labeled for AVP mRNA or stained for AVP immunoreactivity (AVP ir) were found in the paraventricular (PVN), supraoptic (SON) and suprachiasmatic nuclei (SCN) of the hypothalamus. Scattered AVP producing cells were also found in the lateral hypothalamus and the bed nucleus of the stria terminalis (BST). Neither AVP mRNA-labeled nor AVP-ir cells were detected in the amygdala. Although AVP-ir fibers were evident outside of the hypothalamic-neurohypophyseal tract, a plexus of fibers in the lateral septum, as observed in the rat brain, was not detected. Receptor autoradiography using 125I-linear-AVP revealed specific binding for AVP receptors in the nucleus accumbens, diagonal band, lateral septum, the BST, SCN, PVN, amygdala, anterodorsal and ventromedial nucleus of the hypothalamus, indicating sites for central AVP action in the marmoset brain. Together, these data provide a comprehensive picture of AVP pathways in the marmoset brain, demonstrating differences from rodents in the distribution of cell bodies, fibers and receptors. PMID- 9369312 TI - 'Chemical ischemia' in cultured retina cells: the role of excitatory amino acid receptors and of energy levels on cell death. AB - In this study, we determined whether the retina cell death observed in response to an ischemic-like insult is related to an overactivation of the ionotropic glutamate receptors and/or to a collapse of the energy levels. Cultured chick retina cells were submitted to 'chemical ischemia' by metabolic inhibition with sodium cyanide and iodoacetic acid, which block oxidative phosphorylation and glycolysis, respectively. The assessment of neuronal injury was made spectrophotometrically by quantification of cellularly reduced MTT, which gives information about mitochondrial function, or by staining with fluorescein diacetate (FDA), which correlates with changes in the plasma membrane permeability. 'Chemical ischemia' induced both an acute and a delayed time dependent degeneration of chick retina cells. We observed that 2 min after the ischemic insult, the levels of ATP were reduced to a minimum. On the other hand, the metabolic inhibition induced the release of aspartate, glutamate and gamma aminobutyric acid, and the activation of AMPA/kainate receptors during the period of metabolic arrest was partially responsible for the loss of mitochondrial function. However, the NMDA and non-NMDA receptor antagonists (MK-801 and CNQX) did not prevent the plasma membrane damage caused by sodium cyanide and iodoacetic acid. The results show that the collapse of the energy levels, rather than the increase in excitatory amino acids, appears to underlie the observed cell injury, suggesting an important relationship between ischemia-induced depletion of high-energy metabolites and retina cell degeneration. PMID- 9369313 TI - Sensory-evoked high-frequency (gamma-band) oscillating potentials in somatosensory cortex of the unanesthetized rat. AB - A 64-channel epipial electrode array was used to investigate high-frequency (gamma-band) oscillations in somatosensory cortex of the unanesthetized and unrestrained rat. Oscillations were evoked by manual stimulation of the vibrissae and mystacial pad. Stimulation of the contralateral vibrissae resulted in a significant increase in gamma-power during 128-ms epochs taken just following stimulus onset compared to the prestimulus baseline. Stimulation of the ipsilateral vibrissae was completely ineffective in evoking gamma-oscillations in any animals. Sensory evoked gamma-oscillations were constrained to primary (SI) and secondary (SII) somatosensory cortex. When averaged to an arbitrary reference of peak times in one of the channels, these oscillations exhibited a systematic temporal organization, propagating from the rostral portion of SI to the barrel field proper, and finally to SII. These spatiotemporal characteristics were probably produced by intracortical pathways within rodent somatosensory cortex. The rostrocaudal propagation of gamma-oscillations within the barrel field may also reflect whisking patterns observed when the vibrissae are used as a sensory array, suggesting that synchronized gamma-oscillations may play a role in assembling punctate afferent information provided by the vibrissae into a coherent representation of a somatosensory stimulus. PMID- 9369314 TI - Role of impaired cAMP and calcium-sensitive K+ channel function in altered cerebral hemodynamics following brain injury. AB - Previous studies have shown that pial arteries constricted and responses to dilator opioids were blunted after fluid percussion injury (FPI) in newborn pigs. Membrane potential of vascular muscle is a major determinant of vascular tone and activity of K+ channels is a major regulator of membrane potential. Recent data show that opioids elicit dilation via the sequential production of cAMP and subsequent activation of calcium-sensitive K+ (K(Ca2+)) channels by this second messenger. The present study was designed to investigate the effect of FPI on cAMP and K(Ca2+) channel function. Chloralose-anesthetized piglets equipped with a closed cranial window were connected to a percussion device consisting of a saline-filled cylindrical reservoir and a metal pendulum. Brain injury of moderate severity (1.9-2.1 atm) was produced by allowing the pendulum to strike a piston on the cylinder. FPI blunted dilation to the cAMP analogs 8-Bromo cAMP and Sp 8-Bromo cAMPs (10(-8), 10(-6) M), (9 +/- 1 and 16 +/- 1 vs. 2 +/- 1 and 3 +/- 1% dilations to 8-Bromo cAMP before and after FPI, respectively, n = 8). Similarly, FPI attenuated dilation to pituitary adenylate cyclase activating peptide (PACAP), an endogenous activator of adenylate cyclase, and NS 1619, a K(Ca2+) channel agonist (9 +/- 1 and 16 +/- 1 vs. 3 +/- 1 and 5 +/- 1% for NS 1619 10(-8), 10(-6) M before and after FPI, respectively, n = 8). Moreover, FPI attenuated PACAP, methionine enkephalin, leucine enkephalin, and dynorphin induced elevations in CSF cAMP concentration (940 +/- 2, 1457 +/- 50, and 2191 +/ 53 vs. 810 +/- 17, 1033 +/- 36, and 1218 +/- 49 fmol/ml for control, PACAP 10( 8), 10(-6) M before and after FPI, respectively, n = 8). These data show that cAMP and K(Ca2+) channel function is impaired after FPI. Further these data suggest that impaired cAMP and K(Ca2+) channel function contribute to altered cerebral hemodynamics following FPI. PMID- 9369315 TI - Induction of immediate-early gene expression in preoptic and hypothalamic neurons by the glucocorticoid receptor agonist, dexamethasone. AB - Glucocorticoid receptors (GR) exist in several preoptic and hypothalamic nuclei that participate in neuroendocrine control of anterior pituitary function. GR may mediate effects of endogenous steroids on hormone secretion, since intracerebral administration of exogenous ligands alters plasma levels of several pituitary hormones. The following studies utilized selective antisera for the transcriptional proteins, Fos and Jun, to examine whether these immediate-early gene products are upregulated in response to the GR agonist, dexamethasone (DEX). DEX was administered to groups of male rats by either a subcutaneous (s.c., 5.0 mg/kg) or intracerebroventricular route (i.c.v., 10.0 microg/rat); matched controls received vehicle only. Two hours later, the rats were sacrificed by transcardial perfusion, and serial 25 microm sections through the preoptic area and hypothalamus were processed by avidin-biotin immunocytochemistry for Fos- and Jun-like proteins. Animals treated with DEX i.c.v. exhibited Fos-like immunoreactivity (-li) in several sites in close proximity to the third ventricle, including the preoptic and anterior hypothalamic nuclei, and the periventricular zone of the paraventricular nucleus. In the same group, Jun-li was detected only in the arcuate and suprachiasmatic nuclei. Subcutaneous injection of DEX resulted in more widespread immunostaining for Fos, which occurred in lateral, as well as medial, loci in the preoptic area and hypothalamus, whereas Jun-li was restricted to only medial sites. These data show that discrete populations of preoptic/hypothalamic neurons express c fos and/or jun in response to GR activation. The differential distribution of Fos-li following s.c. vs. i.c.v. administration of DEX suggests that steroid induction and/or amplification of this cellular signaling cascade may depend upon resultant hormone concentrations in neural tissue. In addition, the wide pattern of immunolabeling for Fos in the systematically treated group may reflect both central and peripheral (indirect) steroid effects. Additional studies are in progress to characterize those neurons within sites of neuroendocrine significance that exhibit possible upregulation of these regulatory gene products in response to GR stimulation. PMID- 9369316 TI - Enhancement of contextual fear-conditioning by putative (+/-)-alpha-amino-3 hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor modulators and N methyl-D-aspartate (NMDA) receptor antagonists in DBA/2J mice. AB - Previous studies demonstrated that DBA/2J (DBA) mice performed poorly while C57BL/6J (C57) mice performed normally on a number of complex learning and memory tasks. Chronic oxiracetam treatment dramatically improved the performance of DBA mice but not that of C57 mice on the Morris water task and in contextual fear conditioning. The present study demonstrates that acute treatment with nootropics, oxiracetam (10-1000 mg/kg) or aniracetam (10-100 mg/kg), and N-methyl D-Aspartate (NMDA) antagonists, (+)-MK-801 (0.1-3 microg/kg), CPP (0.01-0.3 mg/kg), and (+)-HA-966 (0.1-3 mg/kg), administered prior to training and testing, reversed the contextual learning impairment in DBA mice in a dose-dependent manner without affecting auditory cue conditioning. These effects appeared to be independent of testing order (context vs. auditory cue tests) and were not due to state-dependent learning. The inactive stereoisomers, (-)-MK-801 and (-)-HA-966, were incapable of increasing contextual freezing in DBA mice. In DBA mice, the effects of 30 mg/kg oxiracetam and 100 mg/kg aniracetam were inhibited by the (+/ )-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor antagonists, NBQX, and GYKI-52466. The combined administration of 30 mg/kg oxiracetam and 1 microg/kg (+)-MK-801 produced an additive response. None of the pharmacological treatments altered performance in C57 mice at doses that were effective in DBA mice. These results suggest that DBA mice may be learning impaired due to altered glutamatergic receptor function. PMID- 9369317 TI - Amino-terminus truncated apolipoprotein E is the major species in amyloid deposits in Alzheimer's disease-affected brains: a possible role for apolipoprotein E in Alzheimer's disease. AB - Amyloid deposits in Alzheimer's disease (AD) are composed of amyloid beta protein (A beta) and many other components called amyloid-associated proteins. Apolipoprotein E (apoE) is one of the most important amyloid-associated proteins. The role apoE plays in AD, however, is yet to be determined. In this study, we present the biochemical and histochemical nature of apoE in AD-affected brains using four monoclonal antibodies (mAbs) against apoE and newly established antibodies against the amino-terminal (anti-apoE-N), and carboxyl-terminal regions (anti-apoE-C) of apoE. Competitive ELISA and Western-blot analysis combined with thrombolytic digestion of apoE indicated that our four mAbs recognized at least two different epitopes within a 22-kDa amino-terminal domain of apoE. Using these mAbs and an anti-A beta mAb, double immunostaining showed that the majority of amyloid deposits were stained by both anti-apoE and anti-A beta mAbs, but the minority of them were detected only by either anti-apoE or anti-A beta mAbs. Differences in staining properties between anti-apoE-N and anti apoE-C were that anti-apoE-C recognized both amyloid deposits and astrocytes similar to anti-apoE mAbs, but anti-apoE-N strongly stained only astrocytes. Preliminary semi-quantitative determinations of apoE in CSF and brain homogenate showed that the amount of apoE increased in AD and Creutzfeldt-Jakob disease brains compared to normal samples. Our immunological data, using antibodies specific for the amino and carboxyl termini of apoE, suggest that apoE may, in some circumstances, initiate plaque formation, and that apoE in amyloid deposits has at least part of its amino termini cleaved out. PMID- 9369318 TI - Differential expression of kainate receptors in the basal ganglia of the developing and adult rat brain. AB - Glutamate is the principal excitatory transmitter of the mammalian brain and plays a particularly important role in the physiology of the basal ganglia structures responsible for movement regulation. Using in situ hybridization with oligonucleotide probes, we examined the expression patterns of the five known kainate type glutamate receptor subunit genes, KA1, KA2 and GluR5-7, in the basal ganglia of adult and developing rat brain. In the adult rat, a highly organized and selective pattern of expression of the kainate subunits was observed in the basal ganglia and associated structures as well as in other regions of the brain. KA2 mRNA was abundant in the striatum, nucleus accumbens, subthalamic nucleus and substantia nigra pars compacta, and was present at lower levels in the globus pallidus and substantia nigra pars reticulata. Neither KA1 nor GluR5 expression was observed in the basal ganglia of adult rats, although these messages were present in other regions. GluR6 was highly expressed in the striatum and subthalamic nucleus and to a lesser extent in the substantia nigra pars reticulata, while no hybridization signal was detectable in the large, presumably dopaminergic neurons of the substantia nigra pars compacta. In contrast, GluR7 was strongly expressed in the substantia nigra pars compacta, was present at lower levels in the striatum, globus pallidus and substantia nigra pars reticulata, and was not detectable in the subthalamic nucleus. During postnatal development, expression of the kainate receptor subunits was characteristically highest on postnatal day 1 and declined to adult levels by day 20; however, in the globus pallidus we did observe the transient expression of KA1 and GluR5 between day 1 and day 10. These results demonstrate that the neuronal structures comprising the basal ganglia express a distinct combination of kainate receptor subunit genes, suggesting that the pharmacological properties of the resultant glutamate receptors are likely to be regionally specific. The organization of expression of these genes is established early in life, which is consistent with the important role they may play in establishing the functions of the motor system. PMID- 9369319 TI - Invertebrate proenkephalin: delta opioid binding sites in leech ganglia and immunocytes. AB - The leech Theromyzon tessulatum and the marine mussel Mytilus edulis immunocytes contain a mammalian-like proenkephalin molecule. The opioid precursor was purified by gel permeation chromatography, anti-Met- and Leu-enkephalin-affinity column separation and then by reversed-phase HPLC. The amino acid sequence analysis, determined by Edman degradation, enzymatic treatments and matrix assisted laser desorption time of flight. The structure of the leech proenkephalin material demonstrates considerable amino acid sequence similarity with amphibian proenkephalin (e.g. 25.4% with Xenopus laevis) but it is smaller, 15 kDa vs. 30 kDa. In contrast, Mytilus proenkephalin is not only larger (26 kDa) but it exhibits a higher sequence identity with guinea pig proenkephalin (50%). Both of the invertebrate materials possess Met-enkephalin and Leu-enkephalin in a ratio of 3:1 for Mytilus and 1:2 in the leech. They also contain Met-enkephalin Arg-Gly-Leu and Met-enkephalin-Arg-Phe sequences that are flanked by dibasic amino acid residues, demonstrating cleavage sites. Furthermore, using sequence comparison with bovine proenkephalin A (209-237), enkelytin (FAEPLPSEEEGESYSKEVPEMEKRYGGFM), an antibacterial peptide is found in the proenkephalin of both animals and it exhibits a 98% sequence identity with mammalian material. Finally, opioid binding experiments demonstrate the presence in leech ganglia and immunocytes of delta1 and delta2 opioid receptor subtypes as also found human and Mytilus immune cells. This report constitutes the first complete biochemical characterization of mammalian proenkephalin in invertebrates, demonstrating its origin in simpler animals. PMID- 9369320 TI - Neonatal vs. adult unilateral hippocampal lesions: differential alterations in contralateral hippocampal theta rhythm. AB - Subcortical damage often has more severe consequences in neonates than in adults. For example, unilateral hippocampal lesions in adult rats typically lead to transient memory deficits, whereas neonatal lesions cause lasting learning impairment. We hypothesized that the defects triggered by unilateral damage may include synaptic dysfunction in the contralateral hippocampus. Consequently, we examined the hippocampal theta rhythm, an EEG pattern thought to be associated with learning. Initial comparisons between intact and lesioned rats revealed no obvious differences in basal theta rhythm properties. However, manipulations of ascending brainstem projections to hippocampus with drugs specific for serotonergic, noradrenergic and cholinergic receptors uncovered differences. Antagonism of 5-HT3 receptors known to promote learning significantly increased theta frequency in controls and adult lesioned rats, but not after neonatal damage. In contrast, blockade of noradrenergic-alpha2 receptors had no effect. Antagonism of cholinergic receptors which typically impairs learning disrupted theta and caused irregular, high-amplitude activity that was significantly more pronounced in the lesioned groups. A final approach involved pharmacological facilitation of AMPA receptor-mediated currents, using a drug which enhances memory. This treatment significantly enhanced theta frequency in controls and animals lesioned as adults. In contrast, it failed to do so in rats lesioned at birth. These observations suggest that latent dysfunction in contralateral hippocampal physiology may contribute to the lasting memory deficits seen after unilateral hippocampal lesion in neonates. PMID- 9369321 TI - Role of ventral hippocampus in acquisition, consolidation and retrieval of rat's passive avoidance response memory trace. AB - By means of local administration of tetrodotoxin (TTX) a fully reversible functional inactivation of rat's ventral hippocampus (VH) was obtained in order to characterize the role of this structure in the memorization of a conditioned passive avoidance response (PAR). In Experiment 1, on permanently cannulated animals, TTX (10 ng in 1.0 microl saline) or saline (1.0 microl) was injected uni or bilaterally in the VH, respectively, 1 h before PAR acquisition, immediately after PAR acquisition, and 1 h before PAR retrieval, always performed 48 h after the acquisition trial. It was shown that both pre-acquisition and pre-retrieval VH uni- or bilateral blockades were followed by significant PAR retention impairment, while in post-acquisition only the bilateral blockade determined PAR retention impairment. In Experiment 2, on three different groups of rats, TTX (10 ng in 1 microl saline) was bilaterally administered, under general ketamine anesthesia (100 mg/kg b.w.), into the VH at different post-acquisition delays (0.25, 1.5, 6 h). Retrieval testing, 48 h after treatment, showed that post acquisition bilateral VH blockade caused PAR impairment only when performed 0.25 h after acquisition. The results clearly indicate a role of VH during acquisition, consolidation and retrieval of PAR engram. The experimental evidence is discussed in comparison to previous results concerning TTX dorsal hippocampus blockade effects on rat's PAR and in relation to hippocampal connectivity with the medial septal area and the amygdala. PMID- 9369322 TI - Impaired modulation of AMPA receptors by calcium-dependent processes in streptozotocin-induced diabetic rats. AB - The mechanisms by which diabetes impairs cognitive function are not well established. In the present study, we determined the electrophysiological and biochemical nature of disturbances in the mechanism of long-term potentiation (LTP) in diabetic rats. As previously reported, the administration of streptozotocin (STZ) was found to reduce the magnitude of LTP in the CA1 region of the hippocampus, while the same treatment did not interact with the capacity of the hippocampus to generate long-term depression induced by low-frequency stimulation. In addition, STZ treatment did not modify the component of excitatory postsynaptic potentials mediated by activation of the N-methyl-D aspartate (NMDA) subtype of glutamate receptors, suggesting that NMDA receptor function remained intact in STZ-treated slices. At the biochemical level, the capacity of calcium to increase [3H](RS)-alpha-amino-3-hydroxy-5-methylisoxazole propionic acid (3H-AMPA) binding to glutamate/AMPA receptors in rat brain tissue sections was markedly affected in most regions of the hippocampus of STZ-treated rats. Moreover, changes in 3H-AMPA binding properties elicited by both exogenous phospholipase A2 and melittin, a potent activator of endogenous phospholipases, were also altered in synaptoneurosomes from diabetic rats. Taken together, the present data suggest that the loss of LTP maintenance in STZ-treated rats is more likely the result of disruption of calcium-dependent processes that are suspected to modulate postsynaptic AMPA receptors during synaptic potentiation. Understanding the biochemical factors participating in the impairment of AMPA receptor modulation might provide important clues revealing the very basis of memory deficits in diabetes. PMID- 9369324 TI - Effects of vasopressin and involvement of receptor subtypes in the rat central amygdaloid nucleus in vitro. AB - Effects of arginine-vasopressin (AVP) on neurons in the central amygdaloid nucleus (ACe) were investigated with rat brain slice preparations using extracellular recording methods. Of 160 ACe neurons tested, 70 cells (44%) were excited and 9 cells (6%) were inhibited by bath application of AVP at 3 x 10(-7) M. The excitatory effects of AVP were dose-dependent and the threshold concentration was approximately 10(-10) to 10(-9) M. The excitatory effects of AVP persisted under blockade of synaptic transmission by perfusing with Ca2+-free and high-Mg2+ medium, whereas the inhibitory effects were abolished by synaptic blockade. AVP-induced effects were mimicked by a V1-receptor agonist and completely blocked by a selective V1-antagonist. V2-agonist produced no effects on ACe neurons and V2-antagonist had no effect on AVP-induced excitation. These results showed that the excitatory effect of AVP on ACe neurons was produced by a direct action through the V1-receptors, whereas the inhibitory response of ACe neurons to AVP seemed to be produced by an indirect action. The results of this study suggest that AVP is involved in the amygdala-relevant functions as a neurotransmitter or a neuromodulator. PMID- 9369323 TI - Effects of amisulpride, an atypical antipsychotic which blocks preferentially presynaptic dopamine autoreceptors, on integrated functional cerebral activity in the rat. AB - Amisulpride, a benzamide derivative with an atypical neuroleptic profile relieves the negative symptoms of schizophrenia when administered at low doses (50-150 mg). In an attempt to define the anatomical substrates involved in this action we have studied the effects of amisulpride on regional cerebral glucose utilisation (RCGU) in the awake lightly restrained rat, by quantitative autoradiography using [14C]2-deoxyglucose ([14C]2-DG). Amisulpride was administered 1 h before [14C]2DG i.v. injection, at a dose of 5 mg/kg which resulted in a striatal D2 receptor occupancy of 10% similar to that induced by doses of this compound used for the treatment of negative symptoms of schizophrenia. Amisulpride induced significant RCGU increases in cortical areas, in visual relays, in auditory structures and in several limbic structures. The pattern of changes in RCGU seen with amisulpride clearly differs from that of haloperidol, given at a dose resulting in a similar occupancy of striatal D2 receptors (0.01 mg/kg), which was mostly ineffective. The amisulpride-induced activation of RCGU in specific brain areas involved in the control of cognitive functions and motivational and emotional behavior, may at least in part, explain the efficacy of this compound in the treatment of negative symptoms of schizophrenia. PMID- 9369325 TI - Differential effects of acute administration of clozapine or haloperidol on local cerebral glucose utilization in the rat. AB - We employed the [14C]2-deoxyglucose method in order to map local brain metabolic activity of rats administered 1, 5, or 20 mg/kg of clozapine, or 0.5 mg/kg of haloperidol, as compared to saline. Clozapine produced a dose-dependent reduction of glucose utilization. At the dose of 1 mg/kg, the effects were limited to limbic areas. An additional number of structures were significantly affected following administration of 5 mg/kg (the whole hippocampal formation and septal area, and cortical limbic areas). The dose of 20 mg/kg markedly reduced glucose utilization in most of the areas examined. Haloperidol (0.5 mg/kg) reduced glucose utilization of the orbital cortex, hippocampal formation and septal area, globus pallidus, amygdala, ventral thalamus, and substantia nigra reticulata. The results show that acute administration of clozapine or haloperidol are associated with different distribution patterns of altered cerebral energy metabolism. Clozapine differently from haloperidol, reduces energy metabolism of the nucleus accumbens and other limbic areas. Haloperidol, but not clozapine (1 or 5 mg/kg), affects the substantia nigra reticulata. PMID- 9369326 TI - Integrin Mac-1 and beta-amyloid in microglial release of nitric oxide. AB - The beta-amyloid protein associated with Alzheimer's disease (AD) has been well characterized biochemically; however, its primary biological function and mode of action in AD has not been determined. We have shown previously that beta-amyloid (beta25-35), in combination with interferon-gamma (IFN-gamma), can induce nitric oxide release from cultured hippocampal microglial cells. In the present study, binding of beta-amyloid with the leukocyte integrin Mac-1, a cell surface receptor on microglia, was studied by observing (1) inhibition of beta-amyloid (beta25-35)-mediated release of nitric oxide from cultured microglial cells following exposure to monoclonal antibodies against Mac-1 (anti-CD18 and anti CD11b) and (2) competitive binding of fluorochrome-labeled beta25-35 with anti CD18 or anti-CD11b using fluorescent flow cytometry. Wt.3 (anti-CD18 antibody) and OX42 (anti-CD11b antibody) were as effective as opsonized zymosan at inducing the release of nitric oxide from microglia. Furthermore, Wt.3 and OX42 acted synergistically to induce maximum nitric oxide release. An interaction between beta-amyloid and CD18 of Mac-1 was evidenced by the suppressive action of beta25 35 on Wt.3-mediated release of nitric oxide and the synergistic action between OX42 and beta25-35 in inducing nitric oxide release from microglia. The tissue culture study was supported by competitive binding assays of fluorochrome-labeled beta25-35 and Mac-1 antibodies (Wt.3 or OX42). The majority of microglial cells (71%) did bind biotinylated beta-amyloid in the presence of cytochalasin B, suggesting that beta-amyloid binding to microglia is a receptor-mediated event. Furthermore, pre-exposure to Wt.3, but not OX42, significantly decreased binding of biotinylated beta25-35 to microglia. These findings suggest that CD18 of Mac-1 may play a role in beta-amyloid-mediated release of nitric oxide. PMID- 9369327 TI - Neonatal treatments with the serotonin uptake inhibitors clomipramine and zimelidine, but not the noradrenaline uptake inhibitor desipramine, disrupt sleep patterns in adult rats. AB - Chronic postnatal exposure to clomipramine (CMI), a monoamine uptake inhibitor, results in persistent alterations in adult rat REM sleep. These effects have been ascribed to CMI's ability to block neonatal active sleep (AS). However, these effects have not been obtained with other anti-depressants which also block neonatal AS. We compared the long-term effects on adult rat sleep after postnatal treatments (P8-P21) with either CMI or zimelidine (ZMI, a selective serotonin uptake inhibitor) or desipramine (DMI, a selective noradrenaline uptake inhibitor). ZMI and CMI increased the frequency and decreased the duration of REM sleep bouts, increased the number of nonREM-REM transitions, and increased sigma power in REM and nonREM sleep EEGs in adulthood. In contrast, DMI had no effect on any adult sleep parameters. Since ZMI, DMI and CMI all reduce AS to similar levels, these results suggest that neonatal AS suppression is not responsible for the sleep deficits following CMI or ZMI treatment. However, since ZMI and CMI, but not DMI, increase synaptic concentrations of serotonin, elevated serotonin levels during development may instead be responsible for the long-lasting sleep deficits. PMID- 9369328 TI - Hydrogen cyanide generation by mu-opiate receptor activation: possible neuromodulatory role of endogenous cyanide. AB - Hydrogen cyanide, a gaseous molecule, is produced by white blood cells during phagocytosis. The present study examined the possibility that neuronal-like cells may also produce cyanide following activation. Rat pheochromocytoma (PC12) cells exhibited a low level of cyanide generation that was significantly increased by mu-opiate agonists (hydromorphone, morphine) and blocked by naloxone. A variety of other agonists including bradykinin, nicotine and glutamate did not generate cyanide in PC12 cells. Systemic administration of hydromorphone to rats increased brain cyanide levels by 61% after 15 min. Using microdialysis probes implanted in the cortical-hippocampal areas of the anesthetized rat or in the hypothalamus of the conscious hamster, a 2- to 5-fold increase in cyanide generation was seen after hydromorphone administration and this increase was blocked by naloxone. To determine whether cyanide release by hydromorphone has functional significance in a neuronal system, cyanide enhancement of N-methyl-D-aspartate (NMDA)-induced increased [Ca2+]i was measured in rat cerebellar granule cells. Hydromorphone enhanced the response to NMDA similar to cyanide and the hydromorphone effect was blocked by cyanide scavengers. These data show that cyanide generation is increased in neuronal tissue by a mu-opiate receptor agonist and it is proposed that endogenous cyanide may modulate the NMDA receptor response. PMID- 9369329 TI - Neurosteroid modulation of [3H]flunitrazepam binding in the medulla: an autoradiographic study. AB - Neurosteroids bind to unique sites on the GABA(A) receptor complex and modulate receptor function. The effects of neurosteroids on GABA(A) receptors have been well characterized in forebrain regions. However, little is known about their effects on GABA(A) receptors in the medulla, especially those areas involved in autonomic reflex pathways. Stimulation of [3H]flunitrazepam binding to the GABA(A) receptor by two progesterone metabolites, 3alpha-hydroxy-5alpha-pregnan 20-one (3alpha-OH-DHP) and 3beta-hydroxy-5alpha-pregnan-20-one (3beta-OH-DHP), was studied using autoradiographic methods in the medulla and cerebellum of female rats at estrus. [3H]Flunitrazepam binding was enhanced by 3alpha-OH-DHP in every nucleus examined in the medulla and cerebellum. This effect was stereoselective since 3beta-OH-DHP had no effect on binding in any region. No differences were observed in the degree of stimulation of [3H]flunitrazepam binding by 3alpha-OH-DHP among medullary brain regions. However, in the cerebellum, the stimulation of binding was significantly greater in the granular layer than in the molecular layer. Stimulation of [3H]flunitrazepam binding by 3alpha-OH-DHP in nuclei involved in the baroreflex pathways supports previous studies which report that neurosteroids modulate autonomic regulation of blood pressure. These actions may also underlie alterations in autonomic function during pregnancy. PMID- 9369330 TI - Sensorimotor learning and retention during equilibrium tests in Purkinje cell degeneration mutant mice. AB - In order to determine the consequences of atrophy to the cerebellar cortex on postural sensorimotor learning and performance, a natural mutation, Purkinje cell degeneration (pcd), was used. The homozygous mutants were compared to heterozygous non-ataxic controls on three static beams, two grids (vertical and tilted), a mobile beam (accelerating rotorod), and a coat-hanger. Although their posture was less stable than that of controls, the pcd mutants were not impaired in distance travelled or in latencies before falling on the static beams. Mutant performance on the grids was not impaired in comparison to controls, while a reduction of latencies before falling on the coat-hanger occurred only during the early part of training. On the accelerating rotorod, pcd mutants fell far sooner than controls and spent more time in passive rotation. By contrast to controls, pcd mutants were not able to improve with practice. Both mutants and controls were deficient during a retention test conducted 8 days after acquisition. The cerebellar cortex is critically involved in timing whole body movements during postural adjustments to a mobile beam but not to four types of immobile apparatus. PMID- 9369331 TI - Melatonin rescues dopamine neurons from cell death in tissue culture models of oxidative stress. AB - Dopamine (DA) neurons are uniquely vulnerable to damage and disease. Their loss in humans is associated with diseases of the aged, most notably, Parkinson's Disease (PD). There is now a great deal of evidence to suggest that the destruction of DA neurons in PD involves the accumulation of harmful oxygen free radicals. Since the antioxidant hormone, melatonin, is one of the most potent endogenous scavengers of these toxic radicals, we tested its ability to rescue DA neurons from damage/death in several laboratory models associated with oxidative stress. In the first model, cells were grown in low density on serum-free media. Under these conditions, nearly all cells died, presumably due to the lack of essential growth factors. Treatment with 250 microM melatonin rescued nearly all dying cells (100% tau+ neurons), including tyrosine hydroxylase immunopositive DA neurons, for at least 7 days following growth factor deprivation. This effect was dose and time dependent and was mimicked by other antioxidants such as 2 iodomelatonin and vitamin E. Similarly, in the second model of oxidative stress, 250 microM melatonn produced a near total recovery from the usual 50% loss of DA neurons caused by neurotoxic injury from 2.5 microM 1-methyl-4-phenylpyridine (MPP+). These results indicate that melatonin possesses the remarkable ability to rescue DA neurons from cell death in several experimental paradigms associated with oxidative stress. PMID- 9369332 TI - Activation of locus coeruleus by prefrontal cortex is mediated by excitatory amino acid inputs. AB - We examined the role of excitatory amino acids (EAAs) in activation of noradrenergic locus coeruleus (LC) neurons evoked by electrical stimulation of the medial prefrontal cortex (mPFC) in halothane-anesthetized rats. Microinfusion of the specific N-methyl-D-aspartate antagonist 2-amino-5-phosphonopentanoic acid (AP5, 50 or 100 microM) into the LC significantly suppressed LC responses evoked by mPFC stimulation. Microinfusion of the selective non-NMDA antagonist 6-cyano-7 nitroquinoxaline-2,3-dione (CNQX, 25 or 50 microM) also significantly reduced evoked LC responses. Simultaneous microinfusion of both AP5 and CNQX considerably increased the proportion of LC neurons which exhibited complete suppression of evoked responses (81%), compared to either AP5 or CNQX alone (approximately 50% each). These results indicate that LC activation by mPFC stimulation is mediated by both NMDA- and non-NMDA-type EAA channels. PMID- 9369333 TI - The distribution of the NMDA R1 subunit in the rat hippocampus--an immunocytohistochemical study. AB - In the present study we examined immunocytochemically the distribution of the R1 subunit of NMDA receptors in rat hippocampus. The applied antibody directed against the III-IV transmembrane region of the R1 subunit of NMDA receptors revealed a heterogeneous distribution of NMDA R1 protein which was highest in the CA1 pyramidal layer and lowest in the stratum lacunosum moleculare. The high immunoreactivity that corresponded to the presence of NMDA R1 receptor subunits was observed mainly in layers of cell bodies of hippocampal neurons, such as deep pyramidal layers of CA1, CA2 and CA3 regions and a granular cell layer of the dentate gyrus. The obtained data are discussed in terms of correlation between the receptor localization and the vulnerability of hippocampal neurons to overstimulation associated with activation of NMDA receptors. PMID- 9369334 TI - Extracellular glutamate increases in the lateral hypothalamus and decreases in the nucleus accumbens during feeding. AB - Glutamate release was monitored in the lateral hypothalamus and the nucleus accumbens during a meal using 30 s resolution microdialysis and capillary zone electrophoresis with laser-induced fluorescence. A significant increase in hypothalamic glutamate and a decrease in accumbens glutamate were observed. These results, added to previous pharmacological studies, suggest that glutamatergic synapses in the lateral hypothalamus and the nucleus accumbens might be involved in the control of feeding behavior. PMID- 9369335 TI - Interleukin-1beta does not increase synaptic inhibition in hippocampal CA3 pyramidal and dentate gyrus granule cells of the rat in vitro. AB - Effects of interleukin-1beta (bath-applied; 500 pM) on rat hippocampal CA3 pyramidal and dentate granule cells were studied using intracellular microelectrode recording in vitro. In both cell types membrane input resistance, resting membrane potential and action potential amplitude remained stable throughout. No change was seen in postsynaptic potentials in granule cells. After blocking excitatory synaptic transmission in CA3 pyramids interleukin-1beta was found to consistently decrease synaptic inhibition by about 30%. PMID- 9369336 TI - Methamphetamine-induced serotonin neurotoxicity is attenuated in p53-knockout mice. AB - Methamphetamine (METH) is a drug of abuse that causes deleterious effects to brain monoaminergic systems. The tumor suppressor gene, p53, is thought to play an important role in cell death. In the present study, we have assessed the participation of p53 in METH-induced serotonergic neurotoxicity, by using the mice lacking the gene for p53 protein. Three dosages (2.5, 5.0 and 10.0 mg/kg x 4) of METH were administered to wild-type (p53+/+), heterozygous (p53+/-) and homozygous (p53-/-) p53-knockout mice. The two lower doses caused no significant changes in serotonin (5-HT) transporters in any of the groups. The highest dose (10.0 mg/kg) caused significant decreases in striatal 5-HT transporters in wild type (-31%) and heterozygous (-18%) mice. In contrast, 5-HT transporters were not significantly decreased in homozygous mice. These results suggest that the tumor suppressor, p53, plays an important role in METH-induced serotonergic neurotoxicity in mice brain. These data provide further evidence for a role of p53 in the neurotoxic effects of METH. PMID- 9369337 TI - Coexistence of calcium-binding proteins in vagal and glossopharyngeal sensory neurons of the rat. AB - The presence and coexistence of the calcium-binding proteins (CaBPs), calbindin D 28k, parvalbumin and S100 protein, were immunohistochemically examined in the glossopharyngeal and vagal sensory ganglia, the carotid body and taste buds. The CaBPs were found in each ganglion with the nodose ganglion containing the largest number of CaBP-immunoreactive (ir) cells (calbindin D-28k > or = S100 >> parvalbumin). The coexistence of CaBPs was found in neurons of the nodose, petrosal, and jugular ganglia. Calbindin D-28k-ir neurons in the nodose and petrosal ganglia frequently colocalized S100-ir whereas calbindin D-28k-ir neurons in the jugular ganglion less frequently contained S100-ir. Only small percentages of calbindin D-28k-ir neurons in each ganglion colocalized parvalbumin. Similarly, S100-ir neurons in the nodose and petrosal ganglia frequently colocalized calbindin D-28k-ir whereas S100-ir neurons in the jugular ganglion less frequently contained calbindin D-28k-ir. Moderate to small percentages of S100-ir neurons in each ganglion colocalized parvalbumin. Parvalbumin-ir neurons nearly always colocalized S100-ir in the nodose, petrosal and jugular ganglia. Moderate to small percentages of parvalbumin-ir neurons in each ganglion colocalized calbindin D-28k. Whereas calbindin D-28k- and S100-ir were colocalized in nerve fibers and cells within taste buds of circumvallate papilla of the tongue, the coexistence of these CaBPs could not be determined in the carotid body. These findings suggest a co-operative role for CaBPs in the functions of subpopulations of nodose and petrosal ganglia neurons. PMID- 9369338 TI - Alterations of AMPA-selected glutamate subtype immunoreactivity in the dentate gyrus after perforant pathway lesion. AB - Immunocytochemical techniques were employed to examine the changes in immunolabeling of the alpha-amino-3-hydroxy-5-methyl-4-isoaxolepropionate (AMPA) receptor subunits GluR1 and GluR2/3 within the dentate gyrus 1, 3, 7, 14, 30, and 90 days after a unilateral perforant pathway lesion in the rat brain. Completeness of the lesion was confirmed following examination of Nissl-stained tissue sections at all times post-lesion and acetylcholinesterase (AChE)-stained sections 14, 30 and 90 days post-lesion, the latter providing evidence of compensatory sprouting of cholinergic fibers in the outer molecular layer of the dentate gyrus. Compared to the non-lesioned hippocampus there was no difference in the staining pattern of AMPA receptor subunits in the dentate gyrus of the deafferented hippocampus 1, 3, 7 and 14 days following lesioning of the perforant pathway. In contrast, 30 and 90 days post-lesion, GluR1 immunolabeling was increased in the outer molecular layer of the dentate gyrus (i.e., deafferented zone) ipsilateral to lesion. Likewise, GluR2/3 immunolabeling was increased within the same region although the intensity of the response was less than that which was observed for GluR1. These data suggest that the loss of the perforant pathway fibers results in a compensatory increase in GluR1 and to a lesser extent GluR2/3 immunolabeling of the outer molecular layer at 30 and 90 days post-lesion and further suggest that AMPA receptor subunits play a role in perforant pathway signal transduction. PMID- 9369340 TI - Interaction studies of 5-HT1A receptor antagonists and selective 5-HT reuptake inhibitors in isolated aggressive mice. AB - Recently published studies have suggested that behavioral and neurochemical changes induced by selective serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitors are potentiated by coadministration of a 5-HT1A receptor antagonist. The potentiating effect is hypothesized to be due to antagonism of somatodendritic 5-HT1A autoreceptors. In the present study the effects of concomitant administration of a selective 5-HT reuptake inhibitor with a 5-HT1A receptor antagonist (N-[2-[4-(2-methoxyphenyl)-1-piperazinyl] ethyl]-N-(2 pyridinyl) cyclo-hexanecarboxamide (WAY 100635) or a beta-adrenoceptor and 5 HT1A/1B receptor antagonist (pindolol or (-)-penbutolol) were studied in isolated aggressive mice. WAY 100635 was inactive, but high doses of WAY 100635 produced a marked anti-aggressive effect when combined with a non-effective dose of citalopram or paroxetine. Low doses of pindolol, but not (-)-penbutolol, produced a minor but significant anti-aggressive effect in combination with citalopram or paroxetine. High doses of pindolol or (-)-penbutolol inhibited aggressive behavior, an effect which was reversed by citalopram or paroxetine. The beta adrenoceptor antagonist, metoprolol, but not the alpha1-adrenoceptor antagonist, prazosin, facilitated the anti aggressive effect of citalopram. The significance of these findings is discussed relative to the above hypothesis. PMID- 9369339 TI - NMDA-induced response in pyramidal neurons of the rat medial prefrontal cortex slices consists of NMDA and non-NMDA components. AB - Using the techniques of intracellular recording, we examined and characterized the membrane response induced by N-methyl-D-aspartate (NMDA) and compared the excitatory postsynaptic potentials (EPSPs) elicited by NMDA and by electrical stimulation of the forceps minor in presumed pyramidal cells of the rat medial prefrontal cortex (mPFC) slice preparation. Bath application of NMDA produced EPSPs, membrane depolarization, and bursts of action potentials. These effects were completely blocked by the NMDA receptor antagonist D-2-amino phosphonopentanoic acid (d-AP5). The non-NMDA receptor antagonist 6-cyano-7 nitroquinoxaline-2,3-dion (CNQX) markedly decreased NMDA-induced responses and converted the I-V relationship curve of NMDA from a curvi-linear to the characteristic J-shape, thus indicating the existence of a non-NMDA component. Synaptic responses elicited by electrical stimulation of the forceps minor also consisted of NMDA and non-NMDA components. Both NMDA- and electrical stimulation elicited EPSPs were markedly reduced or completely abolished by using Ca2+-free artificial cerebrospinal fluid (ACSF), ACSF containing either TTX, low Ca2+ plus Cd2+, or a membrane permeable Ca2+ chelator BAPTA-AM (when BAPTA was loaded in the recording electrode, it was without effect). Under these conditions, NMDA induced depolarization was significantly reduced. Taken together, these results suggest that in addition to a direct action on pyramidal neurons, NMDA causes a release of excitatory amino acids (EAAs), which in turn activate non-NMDA receptors. PMID- 9369341 TI - Intracerebroventricular injection of isoproterenol produces its analgesic effect through interleukin-1beta production. AB - The effects of isoproterenol, a beta-adrenoceptor agonist, on the production of interleukin-1beta in the brain and on mechanical nociception were examined in rats. Intracerebroventricular (i.c.v.) injection of isoproterenol at the dose of 3 microg/rat markedly induced interleukin-1beta mRNA in the molecular layer of the hippocampus, medial preoptic area, paraventricular thalamic nucleus, paraventricular hypothalamic nucleus, ventromedial hypothalamic nucleus, dorsomedial hypothalamic nucleus and central gray 1 h after injection. In these regions, interleukin-1beta mRNA was expressed mainly in the glial cells. The thresholds to the mechanical stimulation to the hind paw were elevated by i.c.v. administration of isoproterenol (1 to 10 microg/rat). When isoproterenol was given at the dose of 3 microg/rat, the analgesic effect showed two peaks. The first peak was observed at 60 min after injection and the second was observed at 180 min. The second phase of analgesia was antagonized by coadministration of interleukin-1 receptor antagonist. These results suggest that isoproterenol produces an analgesic effect, at least in part, through the induction of interleukin-1beta expression in the brain. PMID- 9369342 TI - 5-HT1A receptor agonist properties of the antipsychotic, nemonapride: comparison with bromerguride and clozapine. AB - 5-HT1A receptor agonists are thought to enhance the antipsychotic-like effects of dopamine D2 receptor antagonists while reducing their potential to produce extrapyramidal side effects. Thus, 5-HT1A receptor agonist properties of mixed 5 HT1A receptor agonists/D2 receptor antagonists might be of clinical importance. The antipsychotics, clozapine and nemonapride, and the putative antipsychotic, bromerguride, have intermediate to high affinity for 5-HT1A receptors. The present study examined the 5-HT1A receptor agonist activity of nemonapride and bromerguride, in comparison with clozapine, which has partial 5-HT1A receptor agonist properties in vitro. Here, 5-HT1A receptor activation was examined in vitro, by measuring forskolin-stimulated cAMP accumulation in HeLa cells expressing human 5-HT1A receptors, and in vivo, by using microdialysis to measure the extracellular concentration of hippocampal 5-hydroxytryptamine (5-HT) in rats. Nemonapride markedly decreased both forskolin-stimulated cAMP accumulation and the extracellular concentration of 5-HT; both effects were antagonized by the 5-HT1A receptor antagonist, N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2 pyridinyl) cyclohexanecarboxamide (WAY100635). In contrast, clozapine only partially decreased forskolin-stimulated cAMP accumulation and extracellular 5 HT, and only its effects on cAMP accumulation were attenuated by WAY100635. Bromerguride decreased neither forskolin-stimulated cAMP accumulation nor extracellular 5-HT; instead, it antagonized the decrease of cAMP accumulation produced by 5-HT and the decrease of extracellular 5-HT produced by the 5-HT1A agonist (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). The selective D2 receptor antagonist, raclopride, affected neither forskolin-stimulated cAMP in vitro nor extracellular 5-HT in vivo. Thus, in contrast with clozapine and bromerguride, only the novel antipsychotic, nemonapride, exhibited marked 5-HT1A receptor agonist properties both in vitro and in vivo; conceivably, these properties may play a role in its preclinical and clinical effects. PMID- 9369343 TI - Accumbal dopamine overflow after ethanol: localization of the antagonizing effect of mecamylamine. AB - It has been suggested that ethanol exerts its mesolimbic dopamine activating effects and its reinforcing effects via interaction with central nicotinic acetylcholine receptors, thus providing a basis for the often observed covariation between ethanol and nicotine consumption. We have previously demonstrated that the central nicotinic acetylcholine receptor antagonist mecamylamine totally counteracts the ethanol-induced elevation of extracellular dopamine in the nucleus accumbens, as measured by in vivo microdialysis. A contribution of peripheral nicotinic receptor blockade could, however, not be excluded. In the present study, mecamylamine (1.0 mg/kg, i.p.) again totally counteracted the ethanol-induced dopamine overflow, as measured by in vivo microdialysis, while the quarternary nicotinic receptor antagonist hexamethonium (10 mg/kg, i.p.) did not. Furthermore, the increase in accumbal dopamine overflow after systemic ethanol (2.5 g/kg, i.p.) was counteracted by local perfusion of mecamylamine (50 microM) in the ipsilateral ventral tegmental area, but not by mecamylamine perfusion in the nucleus accumbens. Ethanol-induced accumbal dopamine overflow was also counteracted by perfusion of hexamethonium (250 microM) in the ventral tegmental area. These results provide further evidence that ethanol-induced activation of the mesolimbic dopamine system is mediated via stimulation of central nicotinic acetylcholine receptors, and that the receptor population within the ventral tegmental area may be the most important in this regard. It is suggested that antagonists of central nicotinic acetylcholine receptors may be useful in the treatment of alcoholism. PMID- 9369344 TI - Cardioprotective effect of interleukin-10 in murine myocardial ischemia reperfusion. AB - We investigated the cardioprotective effects of rat interleukin-10 in a murine model of myocardial ischemia-reperfusion (20 min ischemia, 24 h reperfusion). Interleukin-10 (100 microg/rat) administered 15 min prior to reperfusion, significantly (P < 0.01) attenuated myocardial injury compared to rats receiving only 0.9% saline as a vehicle, as indicated by a reduced loss of myocardial creatine kinase from the ischemic-reperfused myocardium. Cardiac myeloperoxidase activity was also significantly (P < 0.01) attenuated by interleukin-10 within the ischemic-reperfused region compared to vehicle treated rats. To further investigate the mechanism of interleukin-10 we observed the in vitro adherence of neutrophil to rat vascular endothelium. Interleukin-10 treatment significantly (P < 0.05) attenuated neutrophil adherence to rat superior mesenteric artery endothelium stimulated with interleukin-1beta. Thus, interleukin-10 demonstrated significant cardioprotective effects as evidenced by a decrease in myocardial creatine kinase loss as well as an inhibition of neutrophil accumulation within the myocardium. It appears as though interleukin-10 mediates its effects, at least in part, by inhibiting leukocyte-endothelial interactions. PMID- 9369345 TI - Dopamine constricts porcine pial veins. AB - Dopamine has been shown to induce pial arterial relaxation and constriction in several species. Its mode of action on pial veins, however, remains unclarified. The vasomotor effect of dopamine on porcine pial veins was, therefore, examined using an in vitro tissue bath technique. The results indicated that dopamine constricted exclusively isolated ring segments of pial veins in the presence or absence of active muscle tone. The constriction induced by dopamine was not affected by N(omega)-nitro-L-arginine (L-NNA, 2 x 10(-5) M) or indomethacin (10( 5) M). Only in few preparations was the constriction induced by maximum concentration of dopamine potentiated by L-NNA, suggesting that dopamine at high concentrations may release NO or a NO-related substance. In the presence of L-NNA (2 x 10(-5) M), dopamine-induced constriction was inhibited by phentolamine and yohimbine (but not prazosin) in a concentration-dependent manner with maximum inhibition at 10(-6) M. SKF38393 and 6-bromo-APB (selective dopamine D1 receptor agonists) and LY171555 (a selective dopamine D2 receptor agonist) also induced pial venous constriction exclusively in the presence of L-NNA. The constriction was not affected by phentolamine (10(-6) M). The order of potency for these agonists in the presence of phentolamine, propranolol, guanethidine and L-NNA was: 6-bromo-APB > SKF38393 > dopamine > LY171555. The dopamine-induced constriction in the presence of phentolamine was further inhibited by both SCH23390 (a selective dopamine D1 receptor antagonist) and sulpiride (a selective dopamine D2 receptor antagonist), but was not affected by dopamine D3 or D4 receptor antagonists. These results indicate that dopamine at low and high concentrations induces exclusively constriction of isolated porcine pial veins. The constriction is mediated by postsynaptic alpha2-adrenoceptors, and dopamine D1 and D2 receptors. PMID- 9369346 TI - Pharmacological analysis of responses to ATP in the isolated and perfused canine coronary artery. AB - Vascular responses of the isolated and perfused canine coronary artery to adenosine 5'-triphosphate (ATP) were analyzed pharmacologically. At basal perfusion pressure, ATP induced a vasoconstriction followed by a vasodilation dose-dependently. The potency order for vasoconstriction was alpha,beta-methylene ATP > 2-methylthio ATP > UTP > ATP. That for vasodilation was ATP > 2-methylthio ATP > alpha,beta-methylene ATP >> UTP in the preparations precontracted by 20 mM KCl. Aminophylline inhibited the vasodilation induced by adenosine, but not that induced by ATP. Alpha,beta-methylene ATP and suramin inhibited the vasoconstriction induced by ATP. Reactive blue 2 inhibited the vasodilation induced by ATP, but not the vasoconstriction. Removal of the endothelium by saponin and L-N(G)-nitroarginine inhibited the vasodilation induced by ATP, but indomethacin did not. The results suggest that ATP induces vasoconstriction via P2X purinoceptors on the smooth muscle and vasodilation via P2Y purinoceptors on the endothelium through mainly the release of nitric oxide in the canine coronary artery, respectively. PMID- 9369347 TI - Inhibition of nitric oxide synthase and soluble guanylate cyclase induces cardiodepressive effects in normal rat hearts. AB - Exogenous nitric oxide (NO) has been shown to modulate the contractile force of rat cardiac myocytes. We sought to determine whether endogenous NO-production in the isolated normal rat heart has an effect on myocardial contractility. Hearts of male Wistar rats were investigated using a constant flow perfused non-paced Langendorff preparation. Changes of contractile parameters such as left ventricular peak pressure, dP/dtmax and dP/dtmin, and of coronary perfusion pressure and heart rate were recorded after infusion of the NO-synthase inhibitors N(omega)-nitro-L-arginine (L-NOARG, 0.1 mM, 1.0 mM, n = 6), N(omega) methyl-L-arginine (L-NMMA, 0.1 mM, 1.0 mM, n = 9) and methylene blue (2 microM, 20 microM, n = 6), the NO-donor sodium (Z)-1-(N,N-diethylamino)diazen-1-ium-1,2 diolat (DEA/NO, 0.01 microM, 0.1 microM, n = 12), the specific inhibitor of soluble guanylate cyclase 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 0.1 microM, n = 7) and L-arginine (0.1 mM, 1.0 mM, n = 6). All NO-synthase inhibitors reduced the contractile function of the ventricular muscle before changes in coronary perfusion pressure were evident. The negative inotropic effect of L-NMMA was absent in the presence of an equimolar concentration of L-arginine. ODQ reduced contractile force and coronary perfusion pressure in parallel. By contrast, L-arginine and DEA/NO improved the contractile force of the left ventricle and DEA/NO decreased coronary perfusion pressure. Heart rate was reduced by L-NOARG (1 mM) and methylene blue (20 microM), while DEA/NO (0.1 microM) and L-arginine (1 mM) had a positive chronotropic effect. All these changes were significant (P < 0.05). These results suggest that endogenous NO production exerts a positive effect on myocardial contraction that is mediated by activation of guanylate cyclase. In addition, NO might be involved in regulation of heart rate. PMID- 9369348 TI - Different sympathetic-parasympathetic interactions on sinus rate and atrioventricular conduction in dog hearts. AB - We investigated the sympathetic-parasympathetic interactions involved in SA nodal pacemaker activity and AV conductivity in the anesthetized dog heart. Stimulation of the intracardiac parasympathetic nerves to the SA nodal region (SAPS) and stimulation of the intracardiac parasympathetic nerves to the AV nodal region (AVPS) induced negative chronotropic and dromotropic responses, respectively. Cardiac sympathetic stimulation, aminophylline, 3-isobutyl-1-methylxanthine (IBMX, a relatively pure nonselective phosphodiesterase inhibitor) and methyl-1,4 dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)-p iridine-5-carboxylate (Bay k 8644, a Ca2+ channel agonist) increased sinus rate and decreased AV conduction time. Sympathetic stimulation augmented the negative chronotropic response to SAPS but not the negative dromotropic response to AVPS, IBMX augmented both responses, Bay k 8644 augmented the chronotropic response and attenuated the dromotropic response, and aminophylline did not affect the chronotropic response to SAPS and inhibited the dromotropic response to AVPS. Additionally, when Bay k 8644 directly given via the AV node artery decreased AV conduction time, it attenuated the negative dromotropic response to AVPS and carbachol injected into the AV node artery. These results suggest that the differential sympathetic-parasympathetic interactions on sinus rate and AV conduction are at least partly induced by an interaction between changes in slow inward Ca2+ current or intracellular Ca2+ and the cardiac effects of acetylcholine in the heart in situ. PMID- 9369349 TI - Cardiac ischemia and impairment of vascular endothelium function in hearts from growth hormone-deficient rats: protection by hexarelin. AB - The ability of hexarelin, an effective growth hormone (GH)-releasing hexapeptide, to reverse the worsening of cardiac dysfunction in GH-deficient animals was studied in young male rats passively immunized by administration of an anti-GH releasing hormone (GHRH) serum. Heart preparations from anti-GHRH serum-treated rats, undergoing low-flow ischemia and reperfusion, showed: (1) a progressive increase of left ventricular end-diastolic pressure during the ischemic period and a poor recovery of contractility at reperfusion with a consistent decrease of the left ventricular-developed pressure; (2) a decreased rate of formation of 6 keto-prostaglandin F1alpha (6-keto-PGF1alpha), a stable metabolite of prostacyclin, in perfusates from preischemic and reperfusion periods; (3) an increased vasopressor activity of angiotensin II. Hexarelin (80 microg/kg, bid, s.c.), administered for 15 days to anti-GHRH serum-treated rats, restored to normal the impaired somatotropic function and counteracted the ischemic damage, improving postischemic left ventricular developed pressure to values higher than those of controls. Furthermore, both the generation of 6-keto-PGF1alpha and the vasopressor activity of angiotensin II reverted to those of control preparations. Administration of hexarelin to control rats induced a considerable improvement of postischemic ventricular function of the perfused hearts which was similar to that present in preparations from anti-GHRH serum-treated rats given hexarelin. This protective activity was divorced from any further stimulation of somatotropic function. Collectively, these data indicate that, in GH-deficient rats, hexarelin is capable of restoring somatotropic function and has a beneficial effect in myocardial ischemia and reperfusion damage. In addition, the increased responsiveness of the coronary vasculature to angiotensin II and the decreased generation of prostacyclin in hearts from GH-deficient rats would indicate that for prevention of injury and dysfunction of the vascular endothelium a normal somatotropic function is mandatory. PMID- 9369350 TI - Effects of beta-adrenoceptor blockade on beta-adrenergic signal transduction in cardiomyopathic hamster (BIO 8262) hearts. AB - In myopathic BIO 8262-hamsters beta1-adrenergic stimulation of cardiac adenylyl cyclase has been found to be markedly reduced compared to that of healthy controls. In order to test the hypothesis that the functional uncoupling of beta1 adrenoceptors in diseased hamster hearts is due to agonist-dependent desensitization, we investigated the effects of prolonged treatment with beta adrenoceptor antagonists on cardiac beta-adrenergic signaling. Groups of hamsters aged 240 days received either drinking water, or drinking water containing metoprolol (10 or 100 mg/kg/day) or propranolol (4 or 40 mg/kg/day). After 4 weeks' treatment animals were killed and heart ventricles were prepared for determination of beta1- and beta2-adrenoceptor densities and their functional contribution to stimulation of adenylyl cyclase. Markers of myocardial hypertrophy, i.e. absolute and relative ventricular weight and 5-nucleotidase activity, were not affected by the different treatment regimens. Neither absolute densities nor relative proportions of beta-adrenoceptor subtypes differed between untreated and treated hamster groups. Metoprolol had no effects on the functional efficacy of beta1- and beta2-adrenoceptors. Hamsters treated with high dose propranolol showed unchanged beta1-adrenoceptor function but reduced beta2 adrenergic stimulation of adenylyl cyclase. The findings of the present study demonstrate that the disturbed coupling of cardiac beta1-adrenoceptors to adenylyl cyclase cannot be reversed by in vivo treatment with beta-adrenoceptor antagonists and, therefore, is unlikely to be due to agonist-dependent desensitization. PMID- 9369351 TI - Beta3-adrenoceptors mediate relaxation of guinea pig taenia caecum by BRL37344A and BRL35135A. AB - Beta-adrenoceptor-mediated relaxation of guinea pig taenia caecum was investigated by studying the effects of the beta3-adrenoceptor agonists, BRL37344A [(R*,R*)-(+/-)-4-[2'-[2-hydroxy-2-(3-chlorophenyl) ethylamino] propyl] phenoxyacetic acid sodium salt sesquihydrate] and BRL35135A [(R*,R*)-(+/-)-methyl 4-[2-[2-hydroxy-2-(3-chlorophenyl) ethylamine] propyl] phenoxyacetate hydrobromide]. BRL37344A and BRL35135A caused dose-dependent relaxation of the guinea pig taenia caecum. The concentration-response curves for BRL37344A and BRL35135A were unaffected by propranolol, ICI118551 [erythro-1-(7-methylindan-4 yloxy)-3-(isopropylamine)-but an-2-ol], atenolol, butoxamine, prazosin, yohimbine and phentolamine. Bupranolol produced shifts of the concentration-response curves for BRL37344A and BRL35135A. Schild regression analyses carried out for bupranolol against BRL37344A and BRL35135A gave pA2 values of 5.79 and 5.84, respectively. These results suggest that the relaxant response to BRL37344A and BRL35135A of the guinea pig taenia caecum is mediated by beta3-adrenoceptors. PMID- 9369352 TI - DMPP causes relaxation of rat distal colon by a purinergic and a nitrergic mechanism. AB - The non-adrenergic relaxation of carbachol precontracted longitudinal muscle of the rat distal colon was investigated. Intrinsic nerves were activated by the nicotinic, ganglionic receptor agonist, 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP). DMPP at 1 and 4 microM caused a relaxation that was markedly antagonized by the nerve blocker tetrodotoxin (1 microM) or the nicotinic receptor antagonist, hexamethonium (1 mM). The response to DMPP was significantly antagonized by apamin (an inhibitor of ATP-sensitive K+-channels), by reactive blue 2 (a blocker of P2y purinoceptors) and by an inhibitor of nitric oxide (NO) synthase (N(G)-nitro-L-arginine, L-NNA). The combined treatment with reactive blue 2 and L-NNA reduced the relaxatory response to 1 microM DMPP by 77 +/- 8% and to 4 microM DMPP by 58 +/- 4% of control, but left a residual component. Our results indicate that ATP and NO, together with at least one additional (hitherto unidentified) substance may be inhibitory neurotransmitters in rat distal colon. PMID- 9369353 TI - Dopamine D2-like receptors in the rat kidney: effect of denervation. AB - The effects of monolateral denervation induced by renal artery occlusion on dopamine D2-like receptors were assessed in rat kidney using radioligand binding assay and autoradiographic techniques. [3H]spiperone was used as a ligand. [3H]spiperone was bound specifically to sections of control innervated kidneys with a dissociation constant (Kd) value of 0.07 +/- 0.003 nM and a maximum density of binding sites (Bmax) value of 35.4 +/- 0.16 fmol/mg tissue. Light microscope autoradiography showed the accumulation of silver grains both in the arterial tree and in cortical tubules. At the vascular level, [3H]spiperone binding sites were accumulated primarily in the adventitia and in adventitia media transitional zone. In cortical tubules, the higher density of [3H]spiperone binding sites was noticeable in proximal convoluted tubules. A few binding sites were also found in the glomerular tuft. In denervated kidneys, noradrenaline and dopamine levels were reduced by about 90% and 60% respectively in comparison with control innervated kidneys. Denervation reduced the density of [3H]spiperone binding sites by more than 85%. In denervated kidneys, light microscope autoradiography showed the disappearance of specific vascular binding sites and a remarkable reduction of tubular [3H]spiperone binding sites. The above results indicate that the largest majority of renal dopamine D2-like receptors labelled by [3H]spiperone is prejunctional in location. PMID- 9369354 TI - Ketotifen prevents gastric hyperemia induced by intracisternal thyrotropin releasing hormone at a low dose. AB - The thyrotropin-releasing hormone (TRH) analog, RX 77368, (p-Glu-His-(3,3' dimethyl)-Pro-NH2) injected intracisternally (i.c.) at low doses increases gastric mucosal blood flow through vagal cholinergic and calcitonin gene-related peptide dependent pathways. The influence of the mast cell stabilizer, ketotifen, on i.c. injection of RX 77368 (1.5 ng)-induced changes in gastric mucosal blood flow (hydrogen gas-clearance technique), gastric acid secretion and mean arterial pressure was studied in urethane-anesthetized rats. RX 77368 increased gastric blood flow by 131% and systemic arterial pressure by 11 mm Hg and decreased gastric mucosal vascular resistance by 54% whereas acid secretion was not altered within the 30 min period post injection. Ketotifen had no effect on these basal parameters but abolished i.c. RX 77368-induced increased gastric mucosal blood flow and decreased gastric vascular resistance. These data suggest that mast cells may be part of the peripheral mechanisms involved in vagal gastric hyperemia induced by TRH analog injected i.c. at a low dose. PMID- 9369355 TI - Changes of abdominal temperature and circulating levels of cortisol and interleukin-6 in response to intra-arterial infusions of tumor necrosis factor alpha or tumor necrosis factor-beta in guinea pigs. AB - The sister proteins tumor necrosis factor (TNF)-alpha and TNF-beta share 35% of their amino acid sequence and a number, but not all, of their biological properties. In the present study we infused amounts of 5 microg/kg TNF-alpha, TNF beta (both preparations with identical bioactivities) or of solvent (0.9% sterile saline) into the circulation of guinea pigs and studied the effects on abdominal temperature, on the induction of endogenous formation of interleukin-6 and on levels of cortisol in plasma as a parameter of the activation of the hypothalamic pituitary-adrenal axis. Infusion of TNF-alpha and TNF-beta both resulted in identical circulating TNF-like-activities corresponding to an amount of about 7000 pg/ml. TNF-alpha induced a biphasic fever lasting for more than 6 h, while in response to TNF-beta just the shorter first phase of fever (duration: 120 min) was measured. Circulating interleukin-6 (baseline level: 12-20 International Units (I.U.)/ml) and cortisol (baseline level: 70-120 ng/ml) increased about 6 fold during the first phase of the febrile response 60 min after the start of infusion with TNF-alpha or TNF-beta. Thereafter interleukin-6 and cortisol declined again in response to TNF-beta, but further increased after infusion with TNF-alpha to peak values measured 3 h after the start of infusion (interleukin-6: 258 +/- 52 I.U./ml; cortisol: 790 +/- 167 ng/ml). In animals infused with solvent abdominal temperature and interleukin-6 remained at the baseline values, just cortisol increased slightly. The results demonstrate that TNF-alpha is a much stronger inducer of fever and interleukin-6 production or of HPA-axis activation than TNF-beta in so far as all the investigated responses can be measured for prolonged time in response to TNF-alpha. PMID- 9369356 TI - Different role of serum components and cytokines on alveolar macrophage activation by soluble fungal (1-->3)-beta-D-glucan. AB - In this study, we investigated the mechanism of alveolar macrophage activation by systemic administration of SSG, a soluble highly branched (1-->3)-beta-D-glucan obtained from a fungus Sclerotinia sclerotiorum IFO 9395. Multiple i.v. administration (10 mg/kg; once daily for 10 consecutive days) of SSG enhanced some functions of alveolar macrophages, such as lysosomal enzyme activity and nitric oxide secretion, on day 1 after the last administration, and it also elevated the concentrations of serum protein, interferon gamma and SSG in bronchoalveolar lavage fluid on the same day. On the in vitro assay system, stimulation by SSG alone (500 microg/ml) slightly augmented the lysosomal enzyme activity of alveolar macrophages, but it had no effect on nitric oxide production of cells. Stimulation by serum (1 or 10% mouse serum) or serum components, such as fibronectin (25 microg/ml) and albumin (500 microg/ml), alone strongly augmented only the lysosomal enzyme activity of alveolar macrophages, but it had no effect on nitric oxide secretion from cells, and no synergism or additive-like effect was observed between serum components and SSG. In contrast, stimulation by crude lymphokine (5%) or recombinant murine interferon gamma (100 U/ml) alone did not induce augmentation of lysosomal enzyme activity and nitric oxide production of alveolar macrophages in vitro, but when cells were incubated together with crude lymphokine or recombinant murine interferon gamma and SSG (500 microg/ml), a significant combined effect was observed on both functions of alveolar macrophages. In addition, pretreatment of crude lymphokine or recombinant murine interferon gamma enhanced the expression of beta-D-glucan specific binding sites on the alveolar macrophage surface in vitro though pretreatment by serum components had no effect. Based on these findings, the enhancement of alveolar macrophage functions by systemic administration of SSG appears to be mediated, at least in part, by both the simple effect of serum components including fibronectin and albumin leaked from pulmonary peripheral blood into the alveoli and the synergistic effect between lymphokines released from activated pulmonary T cells and SSG itself entering the alveoli after SSG injection via the priming effect of lymphokines which enhances the expression of beta-D-glucan specific binding sites on the alveolar macrophage surface. PMID- 9369357 TI - Interleukin-2 and -4 induce resistance of granulocyte-macrophage colony stimulating factor to corticosteroids. AB - In vitro pretreatment of human mononuclear blood cells with a combination of interleukin-2 and interleukin-4 decreases corticosteroid receptor affinity and reduces the anti-proliferative effects of corticosteroids. Similar abnormalities have been observed in mononuclear blood cells of steroid-resistant asthmatics. In vitro steroid resistance was induced by 48 h pretreatment of mononuclear blood cells from healthy individuals (n = 10) with interleukin-2 and interleukin-4 (500 Units (U)/ml). The effects of three structurally different corticosteroids (10( 7)-10(-11) M) on lipopolysaccharide-stimulated (10 ng/ml; 20 h) production of granulocyte-macrophage colony-stimulating factor (GM-CSF) were examined. GM-CSF production was efficiently inhibited by all three corticosteroids in the control cultures. Cortivazol was significantly more potent (IC50 = 3 x 10(-11) M) than budesonide and tipredane (IC50 = 2.5 x 10(-10) M and IC50 = 2 x 10(-10) M, respectively). However. interleukin-2 and interleukin-4 pretreatment counteracted the inhibitory effects of all three corticosteroids to a similar degree. The results highlight the importance of interleukin-2 and interleukin-4 in the induction of steroid resistance, since pretreatment of mononuclear blood cells with these cytokines impaired corticosteroid inhibition of GM-CSF production. PMID- 9369358 TI - Reduced striatal vesicular monoamine transporters after neurotoxic but not after behaviorally-sensitizing doses of methamphetamine. AB - Prior studies indicate long-term reductions of striatal dopaminergic markers after sustained, high dose methamphetamine exposures in vivo, suggesting a neurotoxic effect. We have reported lack of regulation of vesicular monoamine transporter type-2 expression, as opposed to other markers of striatal dopaminergic terminals, under conditions that alter dopaminergic transmission without synaptic terminal losses. In the present study, we evaluated the vesicular monoamine transporter and the neuronal membrane dopamine transporter in rat striata after in vivo exposure to neurotoxic or to intermittent, low dose (behaviorally-sensitizing, non-neurotoxic) methamphetamine administrations. Vesicular monoamine transporter binding was measured by autoradiography of (+) [3H]dihydrotetrabenazine, the active isomer of (+/-)-[3H]dihydrotetrabenazine. (+)-Dihydrotetrabenazine bound to a homogeneous population of striatal sites in controls with a Kd of 1.5 nM and a Bmax of 3.8 fmol/microg protein. Neurotoxic methamphetamine treatment reduced both striatal vesicular monoamine transporter ( 26%) and dopamine transporter (-39%) bindings. There were no changes after the non-neurotoxic treatment regimen. The vesicular monoamine transporter may thus be a valuable marker in the further clinical study of psychostimulant drug neurotoxicity. PMID- 9369359 TI - Reduction in the bioelectric properties of swine tracheal submucosal gland cells in culture after daily short-term exposure to cocaine. AB - Chronic use of cocaine has been associated with respiratory complications. In this study, we investigated the effects of daily short-term cocaine exposure on epithelial bioelectric properties and chloride secretion in response to secretagogues in primary culture of swine tracheal submucosal gland cells grown on microporous inserts. Cell cultures exposed continuously to cocaine for 24 h or intermittently for 30 min daily for up to 3 consecutive days, resulted in a concentration-dependent reduction in transwell voltage and transepithelial resistance. Cocaine (300 microM) treatment for 24 h decreased the voltage and resistance by 87 and 75%, respectively. The voltage and resistance were also substantially decreased after 3 days of intermittent cocaine (10-30 microM) exposure. Cocaine exposure protocols used here did not enhance lactate dehydrogenase (LDH) release. Chloride secretion was measured as short-circuit current utilizing Ussing chamber methodology. Cocaine exposure did not change the decreases in short-circuit current caused by amiloride (10 microM), but reduced the increases in short-circuit current induced by acetylcholine and isoproterenol. After 3 days of intermittent cocaine (30 microM) exposure, the maximal acetylcholine and isoproterenol responses were reduced by 67 and 71%, respectively. Therefore, cocaine exposure continuously for 24 h or intermittently for 30 min daily for up to 3 days decreased basal transepithelial voltage as well as resistance and reduced the responses to cholinergic and beta-adrenoceptor agonists. These results suggest that alterations in epithelial function can occur even after daily transient cocaine exposure. PMID- 9369360 TI - Involvement of a cyclic-AMP pathway in group I metabotropic glutamate receptor responses in neonatal rat cortex. AB - 3,5-Dihydroxyphenylglycine (DHPG), (S)-3-hydroxyphenylglycine and (S)-4-carboxy-3 hydroxyphenylglycine (S-4C3HPG) stimulated phosphoinositide hydrolysis in neonatal rat cortical slices, but with lower maximal effect, in comparison with 2S,1'S,2'S-2-(2'-carboxycyclopropyl)glycine (L-CCG I) or (1S,3R)-1-aminocyclo pentane-1,3-dicarboxylic acid (1S,3R-ACPD). DHPG, 1S,3R-ACPD, and S-4C3HPG also evoked a rapidly desensitizing increase in [Ca2+]i in cortical layers of neonatal brain slices. (R,S)-alpha-methyl-4-tetrazolyl-phenylglycine (MTPG), and (R,S) alpha-methyl-4-phosphono-phenylglycine (MPPG) inhibited the increase of phosphoinositide hydrolysis elicited by 1S,3R-ACPD but not that by R,S-DHPG. In contrast, the selective group II receptor agonist (1S,2S,5R,6S)-2-amino-bicyclo [3.1.0]-hexane-2,6-dicarboxylate (LY 354740) potentiated the response of R,S DHPG. Finally, 8-(4-chlorophenylthio)-cAMP, a membrane permeant analogue of cAMP, reversed the stimulatory effect of 1S,3R-ACPD and S-4C3HPG on phosphoinositide hydrolysis and [Ca2+]i mobilization, without affecting the response induced by R,S-DHPG. These data suggest that, in neonatal rat cortex, the activation of group II metabotropic glutamate receptors potentiates the phosphoinositide hydrolysis and [Ca2+]i responses mediated by group I metabotropic glutamate receptors. PMID- 9369361 TI - Biological activities of N6,C8-disubstituted adenosine derivatives as partial agonists at rat brain adenosine A1 receptors. AB - C8-substituted derivatives of the adenosine A1 receptor-selective agonist N6 cyclopentyladenosine (CPA) were evaluated as potential partial adenosine A1 receptor agonists in rat brain. Potencies and efficacies of 8-alkylamino-CPA derivatives were determined in G protein activation assays by their ability to stimulate binding of [35S]guanosine-5'-(gamma-thio)triphosphate ([35S]GTPgammaS) to rat forebrain membranes, by their ability to inhibit forskolin-stimulated adenylate cyclase, and by inhibition of evoked field excitatory postsynaptic potentials (field EPSPs) in hippocampal slices. EC50 values around 1 microM were determined for all C8-substituted CPA derivatives. Increase in chain length of the substituent gradually reduced agonist efficacy in [35S]GTPgammaS binding studies. Only C8-methylamino-, C8-ethylamino- and C8-propylamino-CPA inhibited forskolin-stimulated adenylate cyclase. In contrast, 8-methylamino- and 8 butylamino-CPA were the compounds of highest intrinsic activity in inhibition of field EPSPs in the hippocampus, followed by 8-ethylamino-CPA. 8-Cyclopentylamino CPA was without effect in this tissue, and the propylamino derivative, when applied cumulatively, caused an inhibition which was smaller the higher the concentration used and the longer the application, which is suggestive of drug induced desensitization. These data indicate that 8-aminoalkyl-substituted CPA derivatives act as partial agonists on the brain and may serve as valuable tools to dissect adenosine A1 receptor mediated signal trafficking in various organs. PMID- 9369363 TI - Dopamine D4 receptor and anxiety: behavioural profiles of clozapine, L-745,870 and L-741,742 in the mouse plus-maze. AB - The dopamine D4 receptor has been implicated in the therapeutic effects of the atypical antipsychotic, clozapine. As it has been proposed that anxiolytic-like activity may contribute to the efficacy of this agent in ameliorating the negative symptoms of schizophrenia, the current study employed ethological methods to fully characterize the acute behavioural profiles of clozapine and two more selective dopamine D4 receptor antagonists, L-745,870 (3-[{4-(4 chlorophenyl)piperazin-1-yl)]methyl}-1 H-pyrrolo[2,3b]pyridine) and L-741,742 (5 (4-chlorophenyl)-4-methyl-3-(1-(2-phenylethyl)piperidin-4-yl)is oxazole), in the mouse elevated plus-maze test. Results showed that while clozapine (0.3-6.0 mg/kg) dose-dependently inhibited all active behaviours (arm entries, exploration, rearing) and increased grooming and immobility, it failed to alter the major anxiety indices (percent open entries and open time). In contrast, L 745,870 (0.02-1.5 mg/kg) and L-741,742 (0.04-5.0 mg/kg) did not produce any significant behavioural changes under present test conditions. These data, which contrast markedly with the robust anxiolytic profile of the reference compound, chlordiazepoxide (10.0 mg/kg), provide little support for the suggestion that clozapine possesses anxiolytic-like properties and further indicate that selective dopamine D4 receptor antagonists are ineffective in the modulation of anxiety-related behaviours in the plus-maze. PMID- 9369362 TI - MK-801-induced hyperlocomotion: differential effects of M100907, SDZ PSD 958 and raclopride. AB - The influence of three selective monoamine receptor antagonists on spontaneous locomotion and on the hyperlocomotion induced by the un-competitive N-methyl-D aspartate (NMDA) receptor antagonist [+]-5-methyl-10,11-dihydro-5H-dibenzo-[a,d] cyclohepten-5,10-imine hydrogen maleate (MK-801; dizocilpine) was investigated. The selective and potent 5-hydroxytryptamine (5-HT)2A receptor antagonist R(+) alpha(2,3-dimethoxyphenyl)-1-[2(4-fluorophenyl)ethyl)]-4-piperidine -methanol (MDL100,907; M100907) displayed a clear-cut selectivity for reduction of MK-801 induced as compared to spontaneous locomotion, in that the former was dose dependently (0.001, 0.01, 0.1 mg/kg i.p.) blocked and even totally abolished by the highest dose, while the latter was only modestly affected. Even at high doses of M100907 (up to 9 mg/kg i.p.), spontaneous locomotion was not reduced below 40% of control. The selective dopamine D1 receptor antagonist (-)-[4aR, 10 aR] 1,2,3,4,4a,5,10,10a-octahydro-4-(4-chloro-2-methyl-phenyl)-1-methyl- benzo[g]quinoxaline-6-ol (SDZ PSD 958; 0.017, 0.15, 1.35 mg/kg i.p.) decreased both spontaneous and MK-801-induced locomotion with a slight preference for the latter; spontaneous locomotion was dose-dependently diminished to approx. 10% of controls (at 8 mg/kg i.p.). The dopamine D2 receptor antagonist raclopride ([(-) (S)-3,5-dichloro-N-((1-ethyl-2-pyrrolidinyl) methyl)-6-methoxy-salicylamide tartrate]; 0.11, 0.33, 1.0 mg/kg i.p.) reduced both MK-801-induced and spontaneous locomotion to a similar extent. An orthogonal matrix experimental design, and multiple regression, were used to evaluate the effects of several combinations of different doses of the 5-HT2A receptor antagonist and the dopamine D1 receptor antagonist. No synergistic actions on reduction of spontaneous or MK-801-induced locomotion were detected between M100907 and SDZ PSD 958. If the hyperlocomotion elicited by acutely administered MK-801 is a valid model of at least some aspects of schizophrenia, these results indicate that the 5-HT2A receptor antagonist M100907 will have efficacy in treating this condition. The lack of effect on spontaneous locomotion, suggests that M100907, compared to dopamine receptor antagonists, will be less prone to induce psychomotor side-effects. Ongoing clinical studies will hopefully give the answers in the near future. PMID- 9369364 TI - A dual effect of 5-HT1B receptor stimulation on nociceptive dorsal horn neurones in rats. AB - In this study the modulatory effects of 5-HT1B receptor activation on wide dynamic range neurones in the spinal cord were studied. Extracellular single unit recordings of dorsal horn neurones were performed in intact urethane anaesthetized female Sprague-Dawley rats, and the receptive field distally on one hind paw was electrically stimulated with needle electrodes applied to the skin. The 5-HT1B receptor agonist, CP-93,129 (3-(1,2,5,6-tetrahydropyrid-4 yl)pyrrolo[3,2-b]pyrid-5-one), the 5-HT1A/B receptor antagonist cyanopindolol, and the 5-HT1A receptor antagonist WAY100635 (N-[2-[4-(2-methoxypheny])-1 piperazinyl]ethyl]-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride), were applied directly onto the spinal cord, and single unit responses were counted separately for A beta-, A delta-, C-fibre responses and post-discharge according to the latencies. A dual effect of CP-93,129 was observed: 50 nmol CP-93,129 caused a clear inhibition of the A delta-fibre responses, whereas 50 and 150 nmol CP-93,129 produced a dose-dependent increase in post-discharge without affecting A beta- and C-fibre responses. Application of 50 nmol cyanopindolol or 50 nmol WAY 100635 alone did not affect neither the neuronal A-fibre nor the C-fibre responses, but when 50 nmol cyanopindolol was coadministered with 50 nmol CP 93,129 the effect of CP-93,129 alone was blocked: the A delta-fibre response was not inhibited and the post-discharge was not increased. In contrast, 50 nmol WAY100635 did not block the effect of 50 nmol CP-93,129 when the two drugs were coadministered. These results suggest that stimulation of the 5-HT1B receptors may have both pro- and antinociceptive effects on wide dynamic range neurones in the dorsal horn after repeated electrical stimulation. PMID- 9369365 TI - Functional correlates of heroin sensitization in the rat brain. AB - The aim of the study was to measure the changes in cerebral energy metabolism and c-fos mRNA expression following challenge with heroin in drug-naive rats and in animals previously sensitized to the drug. Acute heroin administration to drug naive-rats produced a generalized metabolic depression. In contrast, challenge with heroin in drug-sensitized rats produced selective metabolic increases in structures belonging to the basal ganglia. These changes were accompanied by increased c-fos mRNA expression in the caudate-putamen nucleus. These results demonstrate that the process of sensitization to heroin is coupled to functional changes that are confined to the subcortical motor circuits of the basal ganglia. PMID- 9369366 TI - Involvement of nitric oxide in development of tail-tremor induced by repeated nicotine administration in rats. AB - Daily administration of nicotine (0.5 mg/kg per day s.c.) to rats caused a tremor that appeared only in the tail (tail-tremor) and which became more marked over 8 days. Nitric oxide (NO) synthase inhibitors, Nw-nitro-L-arginine (10 mg/kg per day i.p.) or Nw-nitro-L-arginine methyl ester (20 and 40 mg/kg per day i.p.), administered each day before nicotine attenuated the development of the tail tremor. However, neither Nw-nitro-L-arginine (2-10 mg/kg i.p.) nor Nw-nitro-L arginine methyl ester (10-40 mg/kg i.p.) affected the tail-tremor that developed after 14 days of repeated nicotine administration. The noncompetitive N-methyl-D aspartate (NMDA) receptor antagonist, MK-801 ((+)-5-methyl-10,11,-dihydro-5H dibenzo[a,b]cyclohepten-5,10-imine hydrogen maleate) at 0.2 mg/kg per day (i.p.), or competitive antagonist, CPP (3-[(+/-)-2-carboxypiperazin-4-yl] propyl-1 phosphonic acid) at 2 mg/kg per day (i.p.), administered each day before nicotine attenuated the development of the tail-tremor. MK-801 (0.01-0.2 mg/kg i.p.) but not CPP (0.5-4 mg/kg i.p.) suppressed the tail-tremor that developed after 14 days of repeated nicotine administration. These results suggest that NO formation mediated by NMDA receptors is involved in the mechanisms underlying the tail tremor induced by the repeated administration of nicotine. PMID- 9369367 TI - Inhibition of rat hippocampal excitability by the Aconitum alkaloid, 1 benzoylnapelline, but not by napelline. AB - The effects of the two structurally related Aconitum alkaloids, 1 benzoylnapelline and napelline, were investigated by extracellular recording of the stimulus-evoked population spike in the CA1 region of rat hippocampal slices in vitro. 1-Benzoylnapelline (1-100 microM) exerted a depressant action on the orthodromic as well as on the antidromic population spike. Napelline failed to evoke a significant effect at concentrations up to 100 microM. The inhibitory action induced by 1-benzoylnapelline was enhanced when the frequency of electrical stimulation was increased. In contrast, reversal of the inhibitory effect was accelerated when stimulation frequency was decreased. The activity dependent mode of action of 1-benzoylnapelline raised the question of whether the drug is effective to suppress epileptiform activity. The results obtained from experiments on epileptiform hippocampal slices revealed a reduction of the burst duration and of the number of spikes in the burst as well as attenuation of the amplitude of the population spikes. These data support the conclusion that 1 benzoylnapelline, in contrast to the structurally related compound, napelline, has an activity-dependent inhibitory action on central neurons. PMID- 9369368 TI - Ca2+-entry blockade by CAF603, a carotane sesquiterpene isolated from Trichoderma virens. AB - Isometric tension recordings and patch-clamp methods were combined to explore the functional effects and mechanisms of action of 8-daucene-3,4-diol (CAF603), a carotane sesquiterpene isolated from the fungus Trichoderma virens. CAF603 (1-100 microM) inhibited the spontaneous motility of guinea-pig portal vein, duodenum and ileum, and the Ca2+-induced tension of depolarized ileum strips. These effects were not antagonized by either iberiotoxin or glyburide. CAF603 increased the spontaneous motility of guinea-pig detrusor muscle, but inhibited the contraction induced by high-KCl, depolarizing salines. CAF603 blocked L-type Ca2+ channel currents of rabbit cardiac myocytes. It is proposed that Ca2+-entry blockade accounts for the inhibitory effects of CAF603 on smooth muscle contractility, whereas the stimulation of spontaneous motility of detrusor muscle is ascribed to blockade of Ca2+-activated K+ (BKCa) channel currents. The latter interpretation is consistent with the allosteric modulation of charybdotoxin binding to BKCa in smooth muscle membranes [Lee et al., 1995. J. Nat. Prod. 58, 1822-1828]. PMID- 9369369 TI - Effects of NMDA receptor antagonists on delta1- and delta2-opioid receptor agonists-induced changes in the mouse brain [3H]DPDPE binding. AB - Male Swiss-Webster mice were injected intracerebroventricularly (i.c.v.) with [D Pen2,D-Pen5]enkephalin (20 microg/mouse) twice a day for 2 days. This procedure resulted in down-regulation of binding sites for [3H][D-Pen2,D-Pen5]enkephalin as evidenced by a 52% decrease in the Bmax value. Twice daily injections of (+)-5 methyl-10,11-dihydro-5H-dibenzo-[a,d]-cyclohepten-5,10-imine (MK-801) (0.1 mg/kg, i.p.) or [(-)3-SR,4a-RS,8a-SR-6-(phosphonomethyl)-1,2,3,4,4a,5,6,7,8,8a-decahy droisoquinoline-3-carboxylic acid] (LY 235959) (2 mg/kg, i.p.), the noncompetitive and competitive antagonist of the N-methyl-D-aspartate (NMDA) receptor, respectively, for 2 days did not alter the Bmax or Kd value of [3H][D Pen2,D-Pen5]enkephalin binding to the mouse brain. Concurrent treatment of MK 801, but not of LY 235959 with [D-Pen2,D-Pen5]enkephalin, reversed the decreases in Bmax value of [3H][D-Pen2,D-Pen5]enkephalin. Twice daily injections of [D Ala2,Glu4] deltorphin II (20 microg/mouse) for 2 days caused an increase in the Kd value, but not the Bmax value of [3H][D-Pen2,D-Pen5]enkephalin to bind to brain membranes. Concurrent treatment of [D-Ala2,Glu4]deltorphin II with LY 235959 reversed the increase in Kd value of [3H][D-Pen2,D-Pen5]enkephalin binding induced by multiple injections of [D-Ala2,Glu4]deltorphin II, but MK-801 had no effect. The results suggest that multiple injections of delta1- and delta2-opioid receptor agonists down-regulate delta1-opioid receptors of the brain by modifying Bmax and Kd values of [3H][D-Pen2,D-Pen5]enkephalin binding, respectively. MK-801 and LY 235959 reverse delta1- and delta2-opioid receptor agonists-induced down regulation of brain delta1-opioid receptor, respectively, apparently by different mechanisms. It is concluded that short term treatment of mice with delta1-opioid receptor agonist down-regulates brain delta1-opioid receptors by decreasing Bmax of the ligand which is partially reversed by concurrent treatment with MK-801 but not by LY 235959. On the other hand, short term treatment of mice with delta2 opioid receptor agonist down-regulates brain delta1-opioid receptors by increasing Kd of the ligand which is partially reversed by concurrent treatment with LY 235959 but not by MK-801. PMID- 9369371 TI - Antihypertensive activity of a nonpeptide angiotensin II receptor antagonist, YM358, in rats and dogs. AB - The antihypertensive activity of YM358, 2,7-diethyl-5-[[2'-(1 H-tetrazol-5 yl)biphenyl-4-yl]methyl]-5H-pyrazolo[1,5-b][1,2,4]tri azole potassium salt monohydrate, a new nonpeptide angiotensin II receptor antagonist, was characterized in rats and dogs. In conscious rats, YM358 after a single oral administration (1-30 mg/kg) lowered blood pressure. The rank order of hypotensive potency of YM358 in conscious rats was 2-kidney, 1-clip renal hypertensive rats > spontaneously hypertensive rats > normotensive rats on the basis of maximum hypotension. YM358 also caused decreases in blood pressure in 2-kidney, 1-clip renal hypertensive dogs and furosemide-treated dogs. Repeated administration of YM358 to 2-kidney, 1-clip renal hypertensive rats for 28 days produced a stable and long-lasting antihypertensive effect without influencing circadian blood pressure and heart rate rhythms. No reflex tachycardia was observed in any animals of either species treated with YM358. Therefore, the pharmacological profile of this compound indicates that YM358 has potential as a useful antihypertensive agent. PMID- 9369370 TI - Pharmacological profile of YM358, a novel nonpeptide angiotensin AT1 receptor antagonist. AB - The pharmacological profile of YM358, 2,7-diethyl-5-[[2'-(1 H-tetrazol-5 yl)biphenyl-4-yl]methyl]-5H-pyrazolo[1,5-b][1,2,4]tri azole potassium salt monohydrate, a novel non-peptide angiotensin AT1 receptor antagonist, was studied in vitro and in vivo. YM358 competed with [125I][Sar1, Ile8]angiotensin II for angiotensin AT1 receptors in rat liver membranes. YM358 displayed competitive kinetics and the pKi value was calculated as 8.79. In contrast, YM358 had little effect on the binding of [125I][Sar1, Ile8]angiotensin II to the angiotensin AT2 receptor in bovine cerebellum. In isolated rabbit aorta, YM358 produced a parallel rightward shift in the concentration-response curve for angiotensin II with a pA2 value of 8.82. YM358 had no effect on the contraction induced by KCl, norepinephrine, serotonin, histamine, prostaglandin F2alpha or endothelin-1 even at 10(-5) M. On the basis of pKi values in the binding assay and pA2 values in the isolated tissues, YM358 was approximately 3-10 times more potent than losartan in antagonizing angiotensin AT1 receptors. In pithed rats, intravenous administration of YM358 inhibited an increase in mean blood pressure induced by intravenous infusion of angiotensin II in a dose-dependent manner. In conscious normotensive rats, YM358 at 3-30 mg/kg p.o. inhibited the angiotensin II-induced pressor response in a dose-dependent manner. YM358 at 30 mg/kg caused maximum and complete inhibition 30 min after dosing, and inhibition lasted more than 24 h. These results demonstrate that YM358 is a potent, AT1-selective and competitive nonpeptide angiotensin receptor antagonist. Moreover, YM358 is both orally active and long-lasting. This pharmacological profile suggests that YM358 would be suitable for the treatment of cardiovascular disorders such as hypertension and chronic heart failure. PMID- 9369373 TI - Cardiovascular effects of elgodipine and nifedipine compared in anaesthetized rats. AB - The cardiovascular effects of elgodipine were studied and compared with those of nifedipine in the presence or absence of ganglion blockade. A bolus of elgodipine (5-25 microg/kg) or nifedipine (60-120 microg/kg) was given and sequential cardiovascular effects in rats were recorded. Both dihydropyridines induced a dose-dependent decrease in mean arterial pressure but, whereas nifedipine induced reflex tachycardia, elgodipine induced a dose-dependent bradycardia. Both substances induced decreases in left ventricular d P/dt(max) without significant changes in central venous pressure. Good linear correlation was observed between the elgodipine-induced decrease in mean arterial pressure and those of heart rate and left ventricular dP/dt(max). The profile of the decrease in mean arterial pressure in animals pretreated with hexametonium chloride (20 mg/kg) was the same but the nifedipine-induced tachycardia was abolished without changes in elgodipine-induced bradycardia. These characteristics of elgodipine makes this dihydropyridine a potentially beneficial therapeutic agent in the case of severe hypertension accompanied by obstructive coronopathy. PMID- 9369372 TI - 17Beta-oestradiol reduces cardiac leukocyte accumulation in myocardial ischaemia reperfusion injury in rat. AB - We investigated whether oestrogens modulate the phenomenon of leukocyte accumulation during ischaemia and reperfusion of the myocardium. Anaesthetized rats were subjected to total occlusion (1 h) of the left main coronary artery followed by 1 h reperfusion. Sham myocardial ischaemia-reperfusion rats (Sham) were used as controls. Myocardial necrosis, myocardial myeloperoxidase activity, serum creatinine phosphokinase activity, serum and macrophages tumour necrosis factor (TNF-alpha) and the myocardial staining of intercellular adhesion molecule 1 (ICAM-1) were evaluated. Myocardial ischaemia plus reperfusion in untreated rats produced marked myocardial necrosis, increased serum creatinine phosphokinase activity (348 +/- 38 U/ml) and cardiac myeloperoxidase activity, a marker of polymorphonuclear leukocyte accumulation, both in the area at risk and in the necrotic area (MPO 9 +/- 1.1 mU/g tissue and 8.2 +/- 1 mU/g tissue, respectively), and induced a marked increase in the macrophage (156 +/- 14 U/ml at the end of reperfusion) and serum (344 +/- 12 U/ml, at the end of reperfusion) levels of TNF-alpha. Finally, myocardial ischaemia-reperfusion injury increased ICAM-1 staining in the myocardium. Administration of 17beta-oestradiol (5, 10 and 20 microg/kg, i.m. 5 min after induction of myocardial ischaemia-reperfusion injury), lowered myocardial necrosis and myeloperoxidase activity in the area at risk and in the necrotic area, reduced serum and macrophages TNF-alpha (20 +/- 3 U/ml and 9 +/- 3 U/ml, respectively) and decreased serum creatinine phosphokinase activity (67 +/- 3 U/ml). Oestrogen treatment also blunted the increased staining of ICAM-1 in the injured myocardium. Finally, 17beta-oestradiol added in vitro to peritoneal macrophages collected from untreated rats subjected to myocardial ischaemia-reperfusion injury, significantly reduced TNF-alpha production. Our results suggest that 17beta-oestradiol, by inhibiting TNF-alpha production, limits the deleterious ICAM-1-mediated binding of leukocytes to injured myocardium and protects against myocardial ischaemia-reperfusion injury. PMID- 9369374 TI - Effect of N(G)-nitro-L-arginine methyl ester on functionally characterized muscarinic receptors in anesthetized cats. AB - This study was undertaken to determine if the nitric oxide (NO) synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), is a competitive antagonist of muscarinic receptors in vivo. Cats were anesthetized with pentobarbital (36 mg/kg, i.p.). Five peripheral muscarinic responses were characterized based on their sensitivity to intravenous administration of atropine (1-100 microg/kg), pirenzepine (1-100 microg/kg) or gallamine (30-3000 microg/kg) as follows: (1) muscarinic ganglionic transmission through the superior cervical ganglion to the nictitating membrane (M1), (2) electrically elicited vagal bradycardia (M2), (3) neurally evoked sudomotor responses (M3; non-endothelial), (4) basal pupil tone in sympathectomized cats (M3; non-endothelial) and (5) methacholine-induced depression of arterial blood pressure (M3; endothelial). Additional groups of animals were administered L-NAME (50 mg/kg, i.v.) to determine if this agent would alter activation of these muscarinic systems. L-NAME was devoid of effect on responses elicited by stimulation of muscarinic M1, M2 and M3 (non endothelial) receptors. In contrast, L-NAME significantly reduced the depressor responses to i.v. methacholine (M3; endothelial), as did its non-alkyl ester congener, L-NA (NG-nitro-L-arginine; 25 mg/kg, i.v.). These results support the conclusion that although L-NAME inhibits synthesis of nitric oxide in vascular endothelial cells, it is not a generalized muscarinic receptor antagonist in vivo. PMID- 9369376 TI - Capsaicin-induced nitric-oxide-dependent relaxation in isolated dog urethra. AB - Capsaicin (5 x 10[-8] to 5 x 10[-5] M) produced a non-adrenergic and non cholinergic phasic relaxation in a concentration-dependent manner in isolated dog urethral preparations precontracted by noradrenaline. The mode of action of capsaicin was investigated with special reference to the possible involvement of endogenous nitric oxide (NO). A marked tachyphylaxis was observed in the responses to capsaicin. Pretreatment with NG-nitro-L-arginine-methyl-ester (L NAME) prevented or markedly reduced the inhibitory effect of L-NAME. Methylene blue inhibited the capsaicin-induced relaxation. In preparations stored at 4 degrees C for 72 h, the reduction in the capsaicin-induced relaxation was significantly greater than that in the relaxation induced by either electrical field stimulation or by sodium nitroprusside. We conclude that capsaicin produces an endogenous-NO-dependent relaxation in the isolated dog urethra via mechanisms that deteriorate during cold storage of the preparations. PMID- 9369375 TI - Involvement of a cannabinoid in endothelium-derived hyperpolarizing factor mediated coronary vasorelaxation. AB - We have recently proposed that an endocannabinoid is the endothelium-derived hyperpolarizing factor (EDHF) and have now tested this hypothesis in the rat isolated perfused heart. In this preparation bradykinin gave rise to nitric oxide and prostanoid-independent relaxations, assessed as reductions in coronary perfusion pressure (ED50 = 14.9 +/- 5.9 pmol; Rmax = 25.2 +/- 2.2%), which are thought to be mediated by EDHF. These relaxations were antagonised by both the highly selective cannabinoid antagonist, SR141716A (1 microM) (Rmax = 8.3 +/- 1.2%, P < 0.001) and by the calcium-dependent potassium channel blocker tetrabutylammonium (300 microM) (Rmax = 6.7 +/- 3.4%, P < 0.01) and were abolished by the EDHF inhibitor clotrimazole (3 microM). The endogenous cannabinoid, anandamide, similarly caused coronary vasorelaxation (Rmax = 32.3 +/ 2.3%), which was abolished by clotrimazole (3 microM) and antagonised by both 300 microM tetrabutylammonium (Rmax = 18.2 +/- 2.8%, P < 0.01) and 1 microM SR141716A (Rmax = 16.4 +/- 3.3%, P < 0.01). Accordingly, these results suggest that EDHF-mediated responses in the rat coronary vasculature are due to an endogenous cannabinoid and that anandamide causes vasorelaxation through potassium channel activation. These findings are, therefore, consistent with our recent proposal that EDHF is an endogenous cannabinoid. PMID- 9369377 TI - Potencies of agonists acting at tachykinin receptors in the oestrogen-primed rat uterus: effects of peptidase inhibitors. AB - The uterotonic potencies of the naturally occurring mammalian tachykinins and the synthetic subtype-selective agonist analogues of these agents [Lys5,MeLeu9,Nlel0]neurokinin A-(4-10) and [Nle10]neurokinin A-(4-10) (tachykinin NK2 receptor-selective), [Sar9,Met(O2)11]substance P (tachykinin NK1 receptor selective) and senktide (tachykinin NK3 receptor-selective) were determined using preparations from oestradiol-treated rats. The endopeptidase 24.11 inhibitor, N [N-[1-(S)-carboxyl-3-phenylpropyl]-(S)-phenyl-alanyl-(S)-isoserine+ ++ (SCH 39370), potentiated responses to neurokinin A, neurokinin B and substance P, but not to [Lys5,MeLeu9,Nle10)]neurokinin A-(4-10) or senktide. [Nle10]neurokinin A (4-10) effects were potentiated by SCH 39370 with amastatin and those to [Sar9,Met(O2)11]substance P were potentiated by SCH 39370 and captopril in combination. In the presence of optimal concentrations of peptidase inhibitors the relative order of agonist potency was: neurokinin A > substance P > neurokinin B for the naturally occurring mammalian tachykinins and [Lys5,MeLeu9,Nle10]neurokinin A-(4-10) > [Nle10]neurokinin A-(4-10) > [Sar9,Met(O2)11]substance P > senktide for the synthetic tachykinin analogues. Thus, while a tachykinin NK2 receptor predominates in the oestrogen-primed uterus, a tachykinin NK1 receptor may also be present. The non-peptide tachykinin NK3 receptor antagonist, SR 142801, did not antagonise the effects of senktide suggesting that tachykinin NK3 receptors do not mediate its relatively minor effect on the uterus of the oestrogen-primed rat. PMID- 9369378 TI - Repaglinide, glibenclamide and glimepiride administration to normal and hereditarily diabetic rats. AB - Repaglinide (1 microg/g body wt), glibenclamide (10 microg/g) or glimepiride (10 microg/g) were administered orally to either fed or overnight fasted normal rats and hereditarily diabetic animals (GK rats). In both fed and starved normal rats, repaglinide provoked a greater and more rapid increase in plasma insulin concentration and an earlier fall in glycemia than those observed after administration of the hypoglycemic sulfonylureas. Likewise, in fed GK rats, the plasma insulin concentration was already increased by 30.0 +/- 1.6% 15 min after administration of repaglinide, whilst a sizeable insulinotropic action of the sulfonylureas was only recorded at much later times. Except for a lower glycemia at the 240th min of the test, there was little to distinguish, in starved GK rats, between control experiments including the oral administration of the solution of carboxymethylcellulose used as vehicle and the experiments conducted with the antidiabetic agents. Several converging observations indicated that glimepiride stimulated insulin release more promptly than glibenclamide. It is proposed that advantage can be taken from these vastly different time-courses of the hormonal and metabolic response to distinct hypoglycemic agents to optimize the control of glucose homeostasis in non-insulin-dependent diabetic subjects. PMID- 9369379 TI - Nitric oxide mediates down regulation of lipoprotein lipase activity induced by tumor necrosis factor-alpha in brown adipocytes. AB - We previously reported that tumor necrosis factor-alpha (TNF-alpha)/cachectin suppresses lipoprotein lipase activity and its gene expression in brown adipocytes differentiated in culture. Recent evidence suggests that the effect of TNF-alpha over various cells is related to the enhanced production of nitric oxide (NO). The present study examined whether the suppressive effect of TNF alpha on lipoprotein lipase activity is mediated by production of NO in the brown adipocytes. A reverse transcription-polymerase chain reaction (RT-PCR) assay revealed that TNF-alpha caused a concentration- and time-dependent expression of inducible NO synthase in brown adipocytes. Increasing concentrations of TNF-alpha (0.5-50 ng/ml) for 24 h resulted in a concentration-dependent decrease in lipoprotein lipase activity with reciprocal increase in nitrite production in the medium. The suppressive effect of TNF-alpha on lipoprotein lipase activity was significantly prevented by NO synthase inhibitors, NG-nitro-L-arginine methyl ester (L-NAME) and aminoguanidine, but not by D-NAME, an inactive isomer. Furthermore, 8-bromoguanosine 3',5'-cyclic monophosphate, cell permeant cGMP, suppressed lipoprotein lipase activity and 1 H-[1,2,4] oxadiazolo[4,3 a]quinoxalin-1-one, a selective inhibitor for soluble guanylate cyclase, restored the TNF-alpha-suppressed lipoprotein lipase activity. These results suggest that TNF-alpha stimulates brown adipocytes to express inducible NO synthase, followed by production of NO, which in turn mediates the suppressive effect of TNF-alpha on lipoprotein lipase activity. The effect of NO is mediated, at least partly, through production of cGMP. PMID- 9369380 TI - Inhibitory effect of 2-phenyl-4-quinolone on serotonin-mediated changes in the morphology and permeability of endothelial monolayers. AB - The integrity of endothelial cell monolayers, a critical requirement for barrier maintenance, is needed for the prevention of edema formation. To investigate the mechanisms by which 2-phenyl-4-quinolone (YT-1) provided protection against serotonin-induced exudation, rat heart endothelial cell cultures were used. In this study, serotonin and phorbol myristate acetate (PMA) caused endothelial cells to became permeable to macromolecules by causing cell contraction and intercellular gap formation. These responses were attenuated by staurosporine, a protein kinase C inhibitor. Further experiments showed that YT-1 (1) did not alter serotonin-mediated early signal events such as protein kinase C activation, (2) protected against serotonin-induced endothelial barrier dysfunction by increasing intracellular cAMP levels, (3) played a role in regulating adenylate cyclase activity, (4) reversed serotonin-induced permeability to macromolecules, an effect which did not correlate with intracellular cGMP concentrations. This study demonstrates a possible mechanism by which YT-1 protects endothelial function and preserves the microvasculature from pharmacologic injury by vasoactive agents. PMID- 9369381 TI - Opioid alkaloids and casomorphin peptides decrease the proliferation of prostatic cancer cell lines (LNCaP, PC3 and DU145) through a partial interaction with opioid receptors. AB - Opioid agonists (ethylketocyclazocine, etorphine, [D-Ala2,D-Leu5]enkephalin (DADLE), [D-Ala2, N-Me-Phe4-Gly-ol]enkephalin (DAGO), [D-Ser2,Leu5]enkephalin Thr6 (DSLET) and morphine were found to inhibit the proliferation of human prostate cancer cell lines (LNCaP, DU145, and PC3), in a dose-dependent manner. The 50% inhibitory concentrations (IC50) were in the picomolar range. In many cases, this effect was antagonized by the general opioid antagonist, diprenorphine, indicating the existence of specific opioid binding sites. Saturation binding experiments with selective ligands and effectors showed no opioid sites on the LNCaP cell line, kappa1 and mu sites on the PC3 cell line, and kappa1, kappa3 and mu sites on the DU145 cell line. In other cases, the opioid effect was not antagonized by diprenorphine, indicating that the action of opioids might be mediated through other membrane receptors. Furthermore, casomorphin peptides, issued from bovine alpha- (alpha-casein-90-95 and alpha casein-90-96) and beta-caseins (beta-casomorphin and beta-casomorphin-1-5), and human alphaS1-casein (alphas -casomorphin and alphaS1-casomorphin amide) inhibited cell proliferation of human prostate cell lines, also by a mechanism partly involving opioid receptors. As opioid neurons can be found in the prostate gland, and casomorphin peptides might reach the gland through the general circulation, the above findings indicate a putative role of opioids in prostate cancer cell growth. PMID- 9369382 TI - 2(3H)-benzoxazolone and 2(3H)-benzothiazolone derivatives: novel, potent and selective sigma1 receptor ligands. AB - A series of original 2(3H)-benzoxazolone and 2(3H)-benzothiazolone derivatives were evaluated for their affinity at sigma1 and sigma2 receptor subtypes in competition binding experiments, using [3H](+)-pentazocine or [3H]1,3-di-o-tolyl guanidine (DTG) in the presence of 100 nM (+)-N-allylnormetazocine (NANM) in guinea-pig brain membranes. Several of these derivatives showed preferential selectivity for sigma1 binding sites. Compound 1 [3-(1-piperidinoethyl)-6 propylbenzothiazolin-2-one] emerged as a potent sigma1 receptor ligand (Ki = 0.6 nM) and displayed a moderate selectivity over the sigma2 receptor subtype (Ki for sigma2/Ki for sigma1 = 29). Compounds 2 [3-(1-piperidinopropyl)-6 propanoylbenzothiazolin-2-one] and 3 [3-(1-piperidinopropyl)-6 propanoylbenzoxazolin-2-one] still showed rather high affinities for sigma1 binding sites with Ki values of 2.3 and 8.5 nM, respectively. On the contrary, they had 87- and 58-fold less affinity at sigma2 receptors, respectively. Unlike their potent affinity for sigma binding sites, these compounds had negligible affinity for mu-, delta- and kappa-opioid receptors, 5-HT2, dopamine D2, and muscarinic M2 receptors. Sigma receptor ligands may affect neuronal transmission and display, in animal models, antipsychotic, cognitive, motor, neuroprotective and anticonvulsant activity. Therefore, on the basis of these findings, these novel sigma receptor ligands were assayed, in mice, in three tests: maximal electroshock, subcutaneous pentylenetetrazol and rotarod neurotoxicity. Compound 1, administered intraperitoneally, was the most effective against maximal electroshock-induced seizures and was devoid of significant neurotoxic effects. PMID- 9369383 TI - Molecular pharmacology of 4-substituted glutamic acid analogues at ionotropic and metabotropic excitatory amino acid receptors. AB - The pharmacology of (2S,4R)-4-methylglutamic acid, (2S,4S)-4-methylglutamic acid and (S)- and (R)-4-methyleneglutamic acids (obtained in high chemical and enantiomeric purity from racemic 4-methyleneglutamic acid by chiral HPLC using a Crownpak CR(+) column), was examined in binding experiments using rat brain ionotropic glutamate receptors, and in functional assays using cloned metabotropic glutamate (mGlu) receptors. As a notable result of these studies, (2S,4R)-4-methylglutamic acid and (2S,4S)-4-methylglutamic acid were shown to be selective for kainic acid receptors and mGlu receptors (subtypes 1alpha and 2), respectively, whereas (S)-4-methyleneglutamic acid showed high but rather non selective affinity for the (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4 yl)propionic acid (AMPA), kainic acid, NMDA and mGlu receptors (subtypes 1alpha and 2). Although none of the compounds were specific for any of the receptor subtypes, the results demonstrate that each of these structurally related compounds has a distinct pharmacological profile. PMID- 9369384 TI - Ethical issues raised by managed care. AB - Health care costs have risen steadily for many years as a result of an inflationary reimbursement system, technologic advances, an aging population, and increasing patient expectations. The growth of managed care organizations (MCOs) has accelerated rapidly in recent years as an attempt to control costs. Because MCOs are involved with medicine, a moral enterprise, they enter the ethical arena. In this report several of the ethical issues raised by the attempted union of potentially conflicting systems are explored. The discussion focuses on four sets of relationships: physician-patient, physician-physician, patient-MCO and medicine-MCO as systems. Some remedies for dealing with the conflicts raised are offered. PMID- 9369385 TI - A classification scheme for paradoxical vocal cord motion. AB - Paradoxical vocal cord motion (PVCM) is characterized by the inappropriate adduction of the true vocal cords during inspiration. Multiple causes have been proposed for this group of disorders, which share the common finding of mobile vocal cords that adduct inappropriately during inspiration and cause stridor by approximation. Management of this group of disorders has been complicated by the lack of a classification scheme to include all types of PVCM. We propose that PVCM be classified according to its underlying etiology and recognize the following causes of the disorder: 1. brainstem compression; 2. cortical or upper motor neuron injury; 3. nuclear or lower motor neuron injury; 4. movement disorder; 5. gastroesophageal reflux; 6. factitious or malingering disorder; 7. somatization/conversion disorder. Case reports are presented to illustrate the characteristic features and diagnostic evaluation used in assessing patients with PVCM. Management varies depending on the cause of PVCM and entails speech therapy, pharmacologic therapy, behavioral modification, and/or surgical intervention. Recognition of the multiple causes of PVCM allows otolaryngologists to formulate well-directed diagnostic evaluation and treatment. PMID- 9369386 TI - Zenker's diverticulum. AB - Symptomatic Zenker's diverticula are usually treated with diverticulectomy and myotomy. Other, more conservative open procedures consist of diverticulopexy, imbrication, and myotomy alone. These more conservative procedures do not result in a breach of esophageal mucosa and should have more rapid postoperative recovery. We performed a retrospective chart review of all open surgical procedures performed at the Marshfield Clinic and St. Joseph's Hospital between 1975 and 1996. Using Wilcoxon's rank sum test, the conservative procedures were compared with the standard diverticulectomy for duration of hospitalization and length of time to resumption of oral intake. Fifty-nine patients are reported. Statistically significant differences between the surgery groups were found for hospitalization (P < 0.001) and days to resumption of oral intake (P < 0.001). Conservative open surgical procedures for repair of Zenker's diverticula result in decreased hospitalization and earlier resumption of oral diet compared with diverticulectomy. PMID- 9369387 TI - Stapedectomy training with the carbon dioxide laser. AB - All primary carbon dioxide (CO2) laser stapedectomies supervised by the senior author since 1986 were retrospectively reviewed and reported according to 1995 American Academy of Otolaryngology-Head and Neck Surgery Committee on Hearing guidelines. Sixty-three cases had more than 6 weeks of follow-up with an average residual gap of 6.49 dB (SD = 5.55 dB) and an 89% success rate. Thirty cases had more than 1 year of follow-up with the average hearing result of 6.58 dB (SD = 5.93 dB) and an 87% success rate. In 11 cases, 14 operative problems or complications occurred. Suctioning the vestibule occurred in five cases. Because suction is required to evacuate laser smoke, these cases are attributed to the laser. One of these patients had delayed sensorineural hearing loss. One patient had profound delayed sensorineural hearing loss as a result of granuloma formation. These were the only major complications. The laser is a tool that gives reproducible technique and good success rates. PMID- 9369388 TI - Thermal effects of laser stapedectomy in an animal model: CO2 versus KTP. AB - Although use of the laser for stapedectomy has become common in recent years, controversy remains regarding whether the CO2 or visible-spectrum lasers (argon and KTP) are best suited for this operation. The main concern has been the potential for thermal injury to the inner ear with the visible-spectrum lasers attributable to their absorption characteristics. To further investigate this issue, the author performed 20 laser stapedectomies on adult chinchillas. Following placement of a 0.127-mm-diameter copper/constantan thermocouple (sampling at 12 Hz) beneath the footplate on the medial wall of the vestibule via a distant fenestration site, thermal changes with a micromanipulator-based CO2 and fiberoptic KTP system were compared. This was the first live animal model comparison of these two lasers. There was no statistical difference in the mean temperature elevation between the two systems (P = 0.395). PMID- 9369389 TI - Fallopian bridge technique in surgery for chronic ear disease. AB - Disease that lies in the posterior mesotympanum, including inflammatory polyps, cholesterol granuloma, and cholesteatoma, is often difficult to extirpate. The literature reflects a divided and often controversial opinion regarding the removal of the bony posterior canal wall to reach this disease. Recently, endoscopic visualization has been advocated to enhance exposure. Employing a fallopian bridge technique wherein the bone medial to the facial nerve is opened into the posterior mesotympanum the authors have used this approach in selective circumstances to optimize the eradication of disease. Three hundred patients undergoing tympanomastoidectomy were included in this analysis. The fallopian bridge technique was attempted in 58 cases and was successfully employed in 42 patients. Indications as well as limitations for this procedure are discussed. PMID- 9369390 TI - Clinical applications of otoacoustic emissions in sudden hearing loss. AB - Sudden hearing loss (SHL) is a controversial topic for which no definitive practical guidelines exist. Studies employing vasodilators, plasma expanders, anticoagulants, and carbogen inhalations have shown no improvement over the rate of spontaneous recovery. At present, there is insufficient evidence to support medical treatment for SHL, except steroid therapy in selected patients. Distortion product otoacoustic emissions (DPOAEs) are sensitive to cochlear disorders and are absent in ischemic injury to the cochlea, but can persist in cochlear neuritis. In a prospective study of 10 patients who presented to Albany Medical Center from 1995 to 1996, three patients with intact DPOAEs at presentation had an average improvement of 33 dB in the pure-tone average (PTA) of 0.5, 1.0, and 2.0 kHz with steroid therapy, whereas five of seven patients with absent DPOAEs had no improvement in hearing despite steroid therapy in six patients. The presence of DPOAEs may be a useful prognostic factor that positively correlates with recovery from SHL. PMID- 9369391 TI - Wound complications associated with brachytherapy for primary or salvage treatment of head and neck cancer. AB - Brachytherapy can be employed in the primary or salvage treatment of head and neck cancer. The advantage of brachytherapy is the stereotactic limitation of radiation exposure to noninvolved tissues. Wound complications associated with brachytherapy have been discussed only sporadically in the literature. This retrospective study examines 28 patients, 20 for initial treatment and eight for salvage, with varying site and stage head and neck cancer treated with brachytherapy in addition to external beam radiation therapy and/or surgery. The overall complication rate was 50% (14/28), with infection and minor flap breakdown being the most common problems. Tumor site in the primary treatment group was the only significant factor in wound complications. In the salvage group complications were minor and primarily related to flap coverage of brachytherapy catheters. PMID- 9369392 TI - Validation of the Charlson comorbidity index in patients with head and neck cancer: a multi-institutional study. AB - Comorbid conditions are medical illnesses that accompany cancer. The impact of these conditions on the outcome of patients with head and neck cancer is well established. However, all of the comorbidity studies in patients with head and neck cancer reported in the literature have been performed using the Kaplan Feinstein index (KFI), which may be too complicated for routine use. This study was performed to introduce and validate the use of the Charlson comorbidity index (CI) in patients with head and neck cancer and to compare it with the Kaplan Feinstein comorbidity index for accuracy and ease of use. Study design was a retrospective cohort study. The study population was drawn for three academic tertiary care centers and included 88 patients 45 years of age and under who underwent curative treatment for head and neck cancer. All patients were staged by the KFI and the CI for comorbidity and divided into two groups based on the comorbidity severity staging. Group 1 included patients with advanced comorbidity (stages 2 or 3), and group 2 included those with low-level comorbidity (stages 0 or 1). Outcomes were compared based on these divisions. The KFI was successfully applied to 80% of this study population, and the CI was successfully applied in all cases (P < 0.0001). In addition, the KFI was found to be more difficult to use than the CI (P < 0.0001). However, both indices independently predicted the tumor-specific survival (P = 0.007), even after adjusting for the confounding effects of TNM stage by multivariate analysis. Overall, the CI was found to be a valid prognostic indicator in patients with head and neck cancer. In addition, because comorbidity staging by the CI independently predicted survival, was easier to use, and more readily applied, it may be better suited for use for retrospective comorbidity studies. PMID- 9369393 TI - Lost airway during anesthesia induction: alternatives for management. AB - Pediatric and adult patients with upper airway obstruction pose several challenges to the anesthesiologist and otolaryngologist--head and neck surgeon. The initiation of general anesthesia and endotracheal intubation may progress to complete life-threatening respiratory decompensation with failure to achieve endotracheal intubation or mask ventilation. Hurried invasive maneuvers such as large-bore needle tracheal entry and cricothyrotomy are recognized salvage techniques, but other modes of extratracheal ventilation are now possible before surgical airway procedures are required. The laryngeal mask airway and esophagotracheal Combitube (Kendall Sheridan Health Care Products Co., Argyle, NY) are described, with examples of their clinical application. The combined technique of anterior commissure laryngoscopy and intubation with the gum elastic bougie is the preferred alternative for achieving tracheal entry when extratracheal ventilation cannot be accomplished. An algorithm for joint management of the problem airway by anesthesiologist and otolaryngologist--head and neck surgeon is illustrated. PMID- 9369394 TI - Trends and perspectives in minimally invasive surgery in otorhinolaryngology-head and neck surgery. AB - The roots of minimally invasive surgery (MIS) in otolaryngology-head and neck surgery (ORL-HNS) can be traced to the 1950s. Today, endonasal sinus surgery and endolaryngeal surgery already fulfill the principles of MIS. To widen its spectrum of indications, however, MIS must be able to offer three advantages that conventional macrosurgery and microsurgery already have: free maneuverability for the instrument, sensory feedback, and three-dimensional imaging. Every anatomical region (e.g., paranasal sinuses, upper aerodigestive tract, cerebellopontine angle) requires specific surgical instrumentation. Here, the authors present recently developed steerable instruments that allow two additional degrees of freedom not attainable with conventional instruments. These instruments may permit access to problem zones (e.g., laterally extending frontal and ethmoidal sinus recesses) in the near future. For better control of the instrument and the operative procedure, tactile feedback can be achieved with appropriate microsensor systems. Three-dimensional vision can be realized by three dimensional video-endoscopes and sequential image processing. PMID- 9369395 TI - Optimizing suicide gene therapy for head and neck cancer. AB - An effective "suicide gene" therapy strategy in experimental studies has been the use of the herpes simplex virus thymidine kinase gene (HSV-tk) to sensitize tumors to the cytotoxic effects of ganciclovir administration. Previous studies using this model have focused on utilizing maximal viral titers and high levels of ganciclovir that are not compatible with human dosing. Because of the high ganciclovir doses and the maximal viral titers, this strategy has limited application to actual clinical scenarios. In the following studies the authors investigate tumor regression in an oral squamous cell carcinoma animal model as a function of variable adenoviral titers and more physiologic ganciclovir dosing. Using adenoviral titers ranging from 1 x 10(8) to 2 x 10(9) plaque forming units (pfu) to treat oral tumors, they found no statistical difference in tumor regression among the different viral doses, despite differences in mitotic activity. Each treatment group, however, demonstrated a significant effect on tumor regression when compared with controls. Furthermore, the authors were able to reduce the level of ganciclovir administration to 10 mg/kg twice daily from established levels of 100 to 150 mg/kg twice daily while maintaining significant tumor responses to the HSV-tk therapy. Mean survival of animals treated with this lower ganciclovir dose was significantly higher than in controls and was equal to established means based on previous studies using higher ganciclovir doses. The optimization of this suicide gene therapy strategy is imperative in order to minimize theoretical and known viral and ganciclovir toxicities while establishing a foundation upon which to design appropriate and effective clinical trials. PMID- 9369396 TI - Frey's syndrome after parotidectomy: a retrospective and prospective analysis. AB - Gustatory sweating is a well-known sequela after parotid surgery. In a retrospective and prospective study of patients undergoing parotid surgery, the onset, time course, extent, and treatment modalities of Frey's syndrome were analyzed. Twenty-two percent of the patients evaluated by questionnaires and 43% of the patients followed prospectively within 1 year were found to be symptomatic. Although the Minor starch-iodine test was positive in 38% of patients at 3 months, none of these patients experienced symptoms. Up to 12 months after surgery the rate of patients who tested positive increased to 96% and the total area of sweating expanded to a mean value of 18 cm2. Whereas most of the patients are not markedly disturbed, few patients (5% to 10%) suffer from severe gustatory sweating. These patients present a therapeutic challenge. PMID- 9369397 TI - Primary laryngeal lymphoma. AB - Primary laryngeal lymphoma is a very rare entity, with fewer than 50 cases reported in the English literature in the past 60 years. Close scrutiny of some of these case reports reveals that the larynx was not always the only site of involvement, thereby diminishing the total number of patients with primary laryngeal lymphoma to fewer than 35. The authors report a series of six patients, who were seen and evaluated at the Mayo Clinic between 1952 and 1995, with stage IAE non-Hodgkin's lymphoma of the larynx. Three patients had large-cell lymphomas according to the REAL (Revised European-American Lymphoid) classification. The other three had a small lymphocytic lymphoma, follicular small cleaved lymphoma, and follicular mixed lymphoma. All patients received radiation therapy alone as initial therapy for their disease and all patients had a complete remission to initial therapy. Four patients subsequently relapsed and the histology at relapse was the same as the initial histology in all four patients. Five patients have died, three of lymphoma, with a median survival of 67 months (range, 40 to 228 months). In view of the heterogeneity of histologies in this group of lymphomas, the variability in duration of response, and the significant number of patients who died of their disease, it is more likely that primary laryngeal lymphoma is an unusual presentation of non-Hodgkin's lymphoma than a separate disease entity. Despite the small number of patients in this study, the data would suggest that patients are best treated according to the histology of the lymphoma, rather than the limited stage and location of the disease. PMID- 9369398 TI - Laryngofissure and cordectomy for glottic carcinoma limited to the mid third of the mobile true vocal cord. AB - The objective of this study was to analyze the long-term results of laryngofissure with cordectomy for invasive glottic squamous cell carcinoma limited to the mid third of the mobile true vocal cord. The authors conducted a retrospective review of the medical charts and operative files of 33 patients with invasive glottic carcinoma limited to the mid third of the mobile true vocal cord managed with laryngofissure and cordectomy. A 10-year follow-up was achieved in 30 patients (90.9%). Kaplan-Meier actuarial analysis of survival, local control, nodal recurrence, distant metastasis, and second primary metachronous tumor was performed. The 5-year actuarial survival, local control, nodal recurrence, and distant metastasis estimates were 97%, 100%, 0%, and 0%, respectively. Tracheotomy was never performed. The overall laryngeal preservation rate was 100%. The 5- and 10-year actuarial metachronous second primary tumor estimates were 3% and 11.5%, respectively. The authors' experience suggested that laryngofissure and cordectomy should still be considered a valuable oncologic option for the management of invasive glottic carcinoma limited to the mid third of the mobile true vocal cord. PMID- 9369400 TI - Quantitative study of nasal secretory cells in normal subjects and patients with chronic sinusitis. AB - The contribution of nasal secretory cells to mucus hypersecretion in chronic sinusitis was investigated. The mucosae of the inferior turbinate were obtained from 18 normal control subjects and 65 patients with chronic sinusitis. Histochemical quantitation showed that there was no significant difference in the number of goblet cells between normal controls and chronic sinusitis. On the other hand, the number of submucosal acinar cells in chronic sinusitis was significantly higher than that in normal controls (P < 0.01). The area occupied by the acini in lamina propria was also increased in chronic sinusitis (P < 0.01). There was no significant difference in the distribution of the intra acinar glycoproteins between normal control subjects and patients with chronic sinusitis. Results suggest that hyperplasia and hypertrophy of nasal acinar cells may have an important role in mucus hypersecretion in chronic sinusitis. PMID- 9369401 TI - Expression of adhesion molecules in nonallergic chronic sinusitis. AB - Endothelial and epithelial adhesion molecules are important in the recruitment of leukocytes to inflammatory sites. To determine the relationship between recruited leukocytes and adhesion molecules in the paranasal sinus mucosa of nonallergic chronic sinusitis, we surgically obtained mucosa from 16 patients and identified the expression of intercellular adhesion molecules (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and P-selectin by immunohistochemistry. Neutrophils were significantly dominant in the nasal discharge as compared with eosinophils. The degree of neutrophil infiltration in the paranasal sinus mucosa was prominent in both intraepithelial and subepithelial areas as compared with the lamina propria. In each tissue site, the degree of infiltration of neutrophils was similar to that of eosinophils. These findings suggest that the tissue neutrophils actively and rapidly migrated into the lumen. All the adhesion molecules except VCAM-1 were expressed in the vascular endothelial cells. On the other hand, the surface epithelial cells showed the expression of only ICAM-1. The expression of ICAM-1 on the endothelial cells correlated with the degree of neutrophil infiltration in the mucosa The eosinophil infiltration was not dependent on any adhesion molecules examined here. It was concluded that ICAM-1 expression in the mucosa may be involved in neutrophil recruitment and may contribute to the establishment of the inflammatory cell distribution in the paranasal sinus of nonallergic chronic sinusitis. PMID- 9369399 TI - Effects of Aspergillus fumigatus and Alternaria alternata on human ciliated epithelium in vitro. AB - Fungi represent the etiologic agent in a large number of patients with chronic sinusitis. Despite this, no study has examined the effects of fungi on ciliated epithelium. This study evaluates the effects of cultures and filtrates of Aspergillus fumigatus and Alternaria alternata on ciliary beat frequency (CBF) in vitro. CBF was recorded after exposure to either a control or experimental solution. A statistical comparison of control and experimental values was performed to determine significance at P < 0.05. A statistically significant inhibition of CBF in cultures and filtrates of A fumigatus and A alternata was demonstrated. We conclude that a soluble metabolite produced by clinical isolates of both A fumigatus and A alternata causes inhibition of CBF and may represent one virulence factor involved in the development of fungal sinusitis. PMID- 9369402 TI - An accurate, cost-effective approach for diagnosing retrocochlear lesions utilizing the T2-weighted, fast-spin echo magnetic resonance imaging scan. AB - Recent data indicate that the auditory brainstem response (ABR) fails to identify a significant number of retrocochlear lesions. Although the magnetic resonance imaging (MRI) scan with paramagnetic enhancement is highly accurate at detecting these lesions, it is time consuming and expensive. We report on our prospective evaluation of a cohort of 155 patients who underwent T2-weighted, fast-spin echo MRI scans designed to screen for retrocochlear lesions. This imaging technique is rapidly performed and provides superb visualization of the relevant anatomic structures at a global cost of $475. Four tumors were identified with this technique. Cost analysis indicates that supplanting ABR with this limited MRI may well represent a cost-effective approach for evaluating patients with suspected retrocochlear lesions. PMID- 9369403 TI - Three-dimensional endoscopic mode for observation of laryngeal structures by helical computed tomography. AB - We produced high-quality three-dimensional (3D) endoscopic images of the larynx using helical scanning computed tomography. Subjects included two normal volunteers and 10 patients: five with laryngeal cancer, four with unilateral recurrent laryngeal nerve (RLN) palsy, and one with atrophied vocal folds. Two vertically split hemilaryngeal images were displayed together with the oral and tracheal views. Although motion artifacts were seen in four patients, laryngeal structures including the vocal fold, ventricular fold, and ventricle were clearly identified in all subjects. In the patients with cancer, axial images showing the extent of the tumor in each patient provided more information than 3D endoscopic images. In the patients with RLN palsy and atrophied vocal fold, combination of 3D endoscopic and cross-sectional images offered more diagnostic information than axial images alone. PMID- 9369404 TI - Perioperative complications of percutaneous dilational tracheostomy. AB - Percutaneous dilational tracheostomy (PDT) has replaced conventional tracheostomy for long-term intubated patients in many intensive care units (ICUs). In a prospective study carried out between September 1994 and August 1996, 76 patients underwent PDT. In 41 patients, PDT was performed "blind." In 35 patients it was executed with simultaneous bronchoscopic monitoring. The type and rate of complications of the two techniques were compared. Comparing the groups with and without bronchoscopy, the perioperative complication rate was equivalent (7% vs 6%); however, more severe complications occurred in the group without bronchoscopy (one death due to tension pneumothorax, two cases of perforating the rear tracheal wall) than in the group with bronchoscopy (two cases of intratracheal hemorrhage). PDT is a suitable bedside method for ICU patients undergoing long-term ventilation. Simultaneous endoscopy minimizes the severity of complications. PMID- 9369405 TI - Submental artery island flap. PMID- 9369406 TI - Pediatric percutaneous revision tracheotomy. PMID- 9369407 TI - Use of silicone stents in the management of subglottic stenosis. PMID- 9369408 TI - Ifosfamide/cisplatin-based chemotherapy in metastatic undifferentiated nasopharyngeal carcinoma. PMID- 9369409 TI - Information booklet for parents of children surviving cancer. AB - With increasing survival rates in pediatric oncology, the medical and psychosocial costs of cure are becoming apparent for the child and his family. The focus of our concern is now how to prevent and to reduce these adverse late effects of cancer and its treatment. To reduce the late psychosocial consequences for the child and its family a booklet was written for parents. We decided to address parents because of the young age of many children when treatment is completed, the essential role of parents in alleviating late effects for the child and his siblings, and the possibility to discuss the whole range of psychosocial late effects: those for the patient, the siblings, and for the parents themselves. The booklet acknowledges the specific emotional problems in patients, parents, and siblings that results from surviving childhood cancer and provides information and support on how to deal with them. The booklet can enhance open communication with the health care team about late consequences. In this way the booklet supports the further integration of medical and psychosocial aftercare. PMID- 9369410 TI - Management of infective complications in patients with advanced hematologic malignancies in home care. AB - A home care service has been implemented at our center with the aim of offering domiciliary assistance to patients with hematologic malignancies in advanced phase. We report our experience concerning the home management of these patients in the setting of infective complications. Of 151 patients in home care, 70 (46%) developed a total of 109 febrile episodes, performance status and neutrophil count significantly affecting the incidence of infections. Fever was of unknown origin in 51% of cases and microbiologically and clinically documented infections accounted for 26 and 23% of the cases, respectively. Oral ciprofloxacin in patients not neutropenic and intravenous ceftriaxone plus amikacin in neutropenic patients was shown to be effective and suitable for empiric home antibacterial treatment; in fact, 65% of febrile episodes responded to the initial antibacterial therapy with a further 16% after modification. Overall, 19.3% of the infective episodes were fatal, the prognosis appearing to be similar to that usually observed in the same category of patients in an inpatient setting. Our experience appears to show that a home care program could be the option of choice for patients with advanced cancer even in the setting of infective complications. It could improve the quality of life of patients and of their families, and it could save these subjects the risk of developing infections by resistant nosocomial isolates. PMID- 9369412 TI - THP-COPBLM (pirarubicin, cyclophosphamide, vincristine, prednisone, bleomycin and procarbazine) regimen combined with granulocyte colony-stimulating factor (G-CSF) for non-Hodgkin's lymphoma in elderly patients: a prospective study. AB - THP-COPBLM including pirarubicin (THP), which is thought to be less toxic than doxorubicin, was used to treat non-Hodgkin's lymphoma (NHL) and the remission rate and adverse effects were studied in 26 patients older than 70 years. Complete remission (CR) was achieved in 19 patients (73.1%) and partial remission in three (11.5%). Classified by stages, CR was achieved in seven out of nine stage II patients and 12 out of 17 stage III, IV patients. The 2-year survival rate was 60.3%. Grade 3 or higher adverse effects included leukopenia in eight patients (30.8%), anemia in three (11.5%), thrombocytopenia in two (7.7%) and nausea/vomiting in 1 (3.8%). The THP-COPBLM regimen appears useful for the treatment of NHL in elderly patients. The regimen was seldom associated with gastrointestinal symptoms and cardiotoxicity. Despite the administration of granulocyte colony-stimulating factor (G-CSF), however, the white blood cell count decreased in many patients, suggesting the necessity for further study of this regimen to modify the dose of THP. PMID- 9369411 TI - Urate oxidase in prevention and treatment of hyperuricemia associated with lymphoid malignancies. AB - Standard prophylaxis and treatment of malignancy-associated hyperuricemia in the USA has been allopurinol with vigorous hydration, urinary alkalinization and osmotic diuresis. Urate oxidase, the enzyme that converts uric acid to allantoin (a readily excreted metabolite that has 5- to 10-fold higher solubility than uric acid), is an alternative therapy; however, few published findings support this practice. Between February 1994 and December 1996, we administered non recombinant urate oxidase (Uricozyme) to 126 children with newly diagnosed non-B cell acute lymphoblastic leukemia (ALL) during the first 5 days of chemotherapy with methotrexate, 6-mercaptopurine or both. Their blood levels of uric acid and other indicators of tumor lysis were measured at diagnosis and during treatment and then compared with findings in 129 similarly treated historical controls who had received allopurinol to control hyperuricemia. Clinical responses to urate oxidase were also determined in eight patients with newly diagnosed B cell ALL or advanced-stage non-Hodgkin lymphoma. Patients treated with urate oxidase had rapid and significantly greater decreases in their blood uric acid levels than did the historical controls (median maximal level during treatment, 2.3 vs 3.9 mg/dl, P < 0.001). They also had lower creatinine (0.6 vs 0.7 mg/dl, P = 0.01) and blood urea nitrogen (11 vs 24 mg/dl, P < 0.001) levels. Similar findings were made in the eight cases of B cell ALL or non-Hodgkin lymphoma. None of the patients required dialysis for acute renal failure. Six (4.5%) of the 134 children given urate oxidase had allergic reactions, manifested primarily by urticaria, bronchospasm and hypoxemia. Thus, non-recombinant urate oxidase is a more effective uricolytic agent than allopurinol but is associated with acute hypersensitivity reactions, even in patients without a history of allergy. PMID- 9369413 TI - Study of the thrombopoitin receptor in essential thrombocythemia. AB - Essential thrombocythemia (ET) is a myeloproliferative disorder associated with megakaryocytic hyperplasia and thrombocytosis. In this disease, in vitro autonomous growth of megakaryocytic colonies has been demonstrated by various investigators. This phenomenon is impaired by the inhibition of the thrombopoietin/c-mpl pathway. In order to evaluate the potential role of mutations of the receptor gene in the origin of this autonomous growth, we compared the expression of c-mpl mRNA isoforms in platelets derived from ET patients and normal subjects. Overlapping c-mpl PCR fragments derived from four ET patients were sequenced to search for small mutations. In the 10 ET and five normal samples we studied, relative expression of the c-mpl isoforms was identical. New variants of Mpl-P and K isoforms, Mpl-P2 and K2 were detected. Cloning of these isoforms indicated that they are produced by alternative splicing of exon 9 sequences shared by Mpl-P and K. Their predicted amino acid sequence would be deleted by 24 aminoacids, upstream of the WSSWS box of the second domain of c-mpl. Two sequence variations, leading to DNA restriction polymorphisms, were present in the extracellular and Mpl-K intracytoplasmic domains. Both were present in normal and ET samples, excluding mutations of c-mpl as a cause of ET. PMID- 9369414 TI - Blood thrombopoietin, IL-6 and IL-11 levels in patients with agnogenic myeloid metaplasia. AB - Agnogenic myeloid metaplasia (AMM) is a disease characterized by bone marrow megakaryocyte hyperplasia and clusters of megakaryocytes, in which many of the megakaryocytes are atypical. In order to elucidate the mechanisms of megakaryocytosis, ELISA assays of blood levels of thrombopoietin (TPO), interleukin-6 (IL-6) and interleukin-11 (IL-11) were done in 45 patients with AMM and compared with normal volunteer controls. Higher blood TPO levels were found in AMM than in controls (P < 0.0001), and blood TPO levels were correlated with the degree of marrow fibrosis (P = 0.0078). Blood levels of IL-6 were also significantly higher in AMM, when compared with controls (P < 0.0001). However, no correlation was found between blood IL-6 levels and degree of marrow fibrosis. No correlation was found between either TPO or IL-6 and the number of blood platelet counts, the number of marrow megakaryocytes, WBC counts, or the degree of splenomegaly. Blood IL-11 levels were undetectable in most patients and no significant difference was found in AMM as compared to controls. The present study demonstrated that, while in idiopathic thrombocytopenic purpura (ITP) or aplastic anemia, blood TPO levels are relatively correlated with the numbers of platelet and/or megakaryocyte mass, blood TPO levels do not correlate with blood platelet counts, or marrow megakaryocyte mass in AMM. Therefore, in AMM, other mechanisms such as the number of TPO receptors on platelets or megakaryocytes, c MPL receptor abnormalities, abnormal production of TPO mRNA and so on, will have to be studied. Furthermore, TPO may play a significant role in the pathogenesis of marrow fibrosis; IL-6 may be a factor in the development of marrow megakaryocytosis but its elevated blood levels may represent a secondary immune phenomenon; and IL-11 probably does not play a significant role in causing marrow megakaryocytosis in this disease. PMID- 9369415 TI - Deficient activation of the CD95 (APO-1/Fas) system in drug-resistant cells. AB - The molecular mechanisms for sensitivity and resistance of tumor cells towards chemotherapy are only partially understood. In chemosensitive leukemias and solid tumors, anticancer drugs have been shown to induce apoptosis. We previously identified activation of the CD95 (APO-1/Fas) receptor/CD95 ligand (CD95/CD95-L) system as a key mechanism for drug-induced apoptosis. Here, we show that therapeutic concentrations of doxorubicin, methotrexate and cytarabine also induce apoptosis via activation of the CD95 system in primary leukemia cells in vivo. CD95-resistant and doxorubicin-resistant leukemia and neuroblastoma cells display cross-resistance for induction of cell death. Down-regulation of CD95 expression was found in drug-resistant and CD95-resistant cell lines. Furthermore, up-regulation of CD95-L, previously shown to mediate drug-induced apoptosis in a variety of tumor cells, was completely blocked in doxorubicin resistant cells. The prototype caspase (ICE/Ced-3 protease) substrate, poly(ADP ribose)polymerase (PARP), was cleaved in sensitive, but not in resistant tumor cells following CD95 triggering or drug treatment. Since failure to activate CD95 L was not due to decreased drug uptake or increased drug efflux, non-multi-drug resistance (non-MDR) mechanisms are involved in this type of resistance. These findings suggested that an intact CD95 system plays a key role in determining sensitivity or resistance towards anticancer therapy. PMID- 9369416 TI - A new look at the role of p53 in leukemia cell sensitivity to chemotherapy. AB - A gene encoding the p53 val135 mutant, which assumes mutant conformation at 38.5 degrees C and wild-type conformation at 32.5 degrees C, was introduced into p53 deficient K562 myeloid leukemia cells. Forced expression of wild-type, but not mutant, p53 resulted in growth arrest, accumulation of p21 and Bax proteins, and delayed cell death. Wild-type p53 enhanced the cytotoxic effects of some drugs and attenuated those of others. Compared with wild-type p53, mutant p53 induced much stronger sensitization to drug cytotoxicity. This occurred in the absence of effects on cell cycle progression or activation of several p53 target genes. Although both mutant and wild-type p53 induced changes of immunophenotype, no specific pattern of differentiation was associated with enhanced chemosensitivity. Thus, (1) induction of growth arrest and activation of p53 target genes such as p21 and bax are linked to the wild-type conformation of p53; (2) p53 induces immunophenotypic changes of myeloid leukemia cells suggestive of multidirectional differentiation in a conformation-dependent manner; and (3) (so called) mutant p53 induces chemosensitization in the absence of effects on cell cycle progression, activation of bax, p21, gadd45 and mdm-2, or a specific pattern of differentiation; and (4) chemosensitization mediated by wild-type p53 may be masked by transcription-dependent induction of growth arrest. PMID- 9369417 TI - Expression of c-Kit and functional drug efflux are correlated in de novo acute myeloid leukaemia. AB - P-glycoprotein (Pgp), the major mediator of multidrug resistance (MDR) has often been implicated as a poor prognostic indicator in acute myeloid leukaemia (AML). We have previously reported that high expression of the receptor tyrosine kinase c-Kit in AML is associated with poor prognosis. To determine whether the MDR phenotype is associated with high c-Kit expression, the monoclonal antibodies UIC 2 and YB5.B8, which identify Pgp and c-Kit, respectively, were used for indirect immunofluorescence labelling of 50 de novo AML specimens. Quantitative dye efflux studies using Rhodamine123 were also carried out to assess the functional drug efflux capability of these samples. Pgp expression by the majority of primary AML was comparable to that seen in subsets of cells from normal bone marrow and Spearman rank analysis showed no relationship with c-Kit expression (rs = 0.20, P = 0.16). However, c-Kit expression did show a significant correlation with Rhodamine123 efflux (rs = 0.57, P = 0.0001), suggesting that the MDR phenotype, Pgp mediated or other, may contribute to the prognostic significance of high c Kit expression. The monoclonal antibody UIC-2 was used specifically to block Pgp activity of a limited number of leukaemic specimens and cell lines, and evidence of non-Pgp-mediated efflux was found. The existence of alternative mechanisms may explain the relatively low correlation of Pgp expression with dye efflux within the leukaemic samples (rs = 0.47, P = 0.0006) and has implications for prognosis in AML. The c-Kit ligand, stem cell factor, did not influence drug efflux activity of the nine c-Kit-positive AML specimens tested. Thus the correlation between c-Kit and the MDR phenotype in AML is likely to be a consequence of co expression at a similar stage of differentiation, and may account for the previously observed association of high c-Kit expression with poor outcome. PMID- 9369418 TI - Cell cycle arrest and apoptosis of leukemia cells induced by L-asparaginase. AB - Apoptotic cell death of murine leukemia cells induced by E. coli L-asparaginase was studied. Deprivation of L-asparagine from the culture of L5178Y cells by L asparaginase caused the fragmentation of chromosomal DNA of the leukemia cells within 24 h. Prior to the degradation of DNA, cell cycles of L5178Y cells were found to be arrested in G1 phase, and evidence of the DNA strand breaks was initially observed in G1 phase cells as early as 8 h after the asparaginase treatment. Therefore, apoptosis of leukemia cells induced by L-asparaginase is an event that is associated with the cell cycle arrest in G1 phase. PMID- 9369419 TI - In vitro activation of low-grade non-Hodgkin's lymphoma by murine fibroblasts, IL 4, anti-CD40 antibodies and the soluble CD40 ligand. AB - The in vitro analysis of growth regulation in low-grade B non-Hodgkin's lymphoma (B-NHL) is hampered by the rapid apoptotic death of the malignant B cells ex vivo. A complex culture system, using murine CDw32 transfected fibroblasts (LTK cells), IL-4 and anti-CD40 mAb, has been established for the propagation of normal mature B cells in vitro. We investigated the influence of the different components of this coculture system on cell survival and apoptosis of B-NHL cells. Nine samples from patients with follicular lymphoma and from eight patients with immunocytoma were analyzed. No cell proliferation of B-NHL cells could be induced in the culture system. However, CDw32-transfected murine fibroblasts most efficiently supported cell viability of B-NHL cells with an increase in cell survival by 114% compared to the control (P = 0.047). IL-4 alone also had a stimulatory effect on cell survival of B-NHL cells after 6 days. In contrast, the soluble recombinant CD40 ligand gp39 and the anti-CD40 mAbs mAb89 and EA-5 did not prolong cell survival. CDw32 transfectants blocked apoptosis of B-NHL cells efficiently from 67% in the control to 16% (P = 0.001). Reduction in apoptosis was accompanied by an elevated bcl-2 protein expression. IL-4 or mAb89 did not further reduce apoptotic cell death in CDw32 transfectant-dependent cocultures. Our data underline the pivotal role of LTK- cells for cell survival of B-NHL cells in vitro. The efficient blockage of apoptosis associated with increased bcl-2 protein expression causes prolonged cell viability of the B-NHL cells. PMID- 9369420 TI - Malignant and reactive cells from human lymphomas frequently express Fas ligand but display a different sensitivity to Fas-mediated apoptosis. AB - Fas ligand (FasL) is capable of inducing apoptosis of lymphoid cells by cross linking with its natural receptor, Fas. We aimed to investigate the possible role of the Fas/FasL-mediated apoptosis in the development of human lymphomas. FasL mRNA was detected by reverse transcriptase-polymerase chain reaction in 38 out of 63 lymphoma biopsy specimens representative of various subtypes of non-Hodgkin's lymphoma (NHL) and Hodgkin's disease. FasL was co-expressed with Fas mRNA in most cases. Flow cytometry (FACS) analysis showed a bright FasL staining in 31% to up to 75% of the total cell population from 14 out of 16 samples; the presence of the FasL protein was confirmed by Western blotting. Dual-color FACS analysis showed that FasL was expressed by T cells in B-NHLs and T-NHLs. A significant percentage of B cells in various B-NHLs also stained positively for FasL. Freshly separated neoplastic B cells from three FasL+ and one FasL- B-NHLs displayed a relative resistance to Fas-mediated apoptosis, when compared to reactive T cells isolated from the same tissue samples. In contrast, the sensitivity to Fas mediated killing of the T cells isolated from two FasL+ T-NHLs was not uniform. These data show that (1) FasL is expressed in both neoplastic and reactive cells from a significant proportion of lymphoma cases, and (2) that the intratumoral FasL+/Fas+ reactive T cells are more sensitive to Fas-induced apoptosis than the neoplastic FasL+/Fas+ malignant B cells. A putative defect in the Fas/FasL pathway may thus favor the development of malignant B cell populations. PMID- 9369421 TI - Flow cytometry CD45 gating for immunophenotyping of acute myeloid leukemia. AB - A flow cytometry method has been introduced into the routine investigation of whole bone marrow samples following red blood cell lysis on the basis of a primary CD45/side scatter (SSC) gating procedure. Blast cells were first identified by CD45/SSC gating in 74 cases of acute myeloid leukemia (AML) and the results were compared to a conventional FSC/SSC gating procedure and to MGG staining smears. The percentages of blast cells in these samples as defined by the morphological analysis of MGG smears correlated better with the values determined by CD45/SSC gating (r = 0.94) than with the blast cell counts recorded with FSC/SSC gating (r = 0.76). These findings were not surprising because while CD45 expression was regularly lower on leukemic blasts than on normal lymphoid and monocytic cells, the FCS/SSC characteristics of these populations were overlapping. In 53 samples, the blast cell populations were also analyzed with a panel of FITC-conjugated monoclonal antibodies that were utilized in double labeling with CD45-PE. We show that the CD45/SSC gating procedure improved phenotypic determination of the blast cells in three ways: (1) by discriminating between leukemic blast cells and residual normal cells; (2) by excluding normal cells from the phenotypic analysis of leukemic blast cells; and (3) by identifying blast cell heterogeneity in many cases of leukemia on the basis of different CD45 display. Moreover, this immunophenotyping procedure on whole bone marrow samples also allowed an efficient discrimination between the various cell lineages and facilitated the analysis of leukemic blasts present in low proportions. PMID- 9369422 TI - Expression of CD25 (interleukin-2 receptor alpha chain) in adult acute lymphoblastic leukemia predicts for the presence of BCR/ABL fusion transcripts: results of a preliminary laboratory analysis of ECOG/MRC Intergroup Study E2993. Eastern Cooperative Oncology Group/Medical Research Council. AB - Of 144 adult Eastern Cooperative Oncology Group (ECOG) patients with acute lymphoblastic leukemia (ALL) entered on study E2993 at the time of analysis, 104 had informative immunophenotypes and molecular analysis by polymerase chain reaction for BCR/ABL fusion transcripts. In 23 patients (22%), BCR/ABL transcripts were detected: the ALL-typical e1a2 alone in 12, e1a2 + b2a2/b3a2 in five, and b2a2 and/or b3a2 in six. Of BCR/ABL-positive patients, 83% had early pre-B ALL, one patient had pre-T ALL, while half of the BCR/ABL-negative patients had early pre-B ALL, 18% had CD10-negative pro-B ALL and 21% were pre-T. When antibodies to both the interleukin-2 receptor alpha (CD25) and beta chain (CD122) were tested, CD25 was expressed significantly more frequently in BCR/ABL-positive (median 23% positive blast cells, range 1-84%) than BCR/ABL-negative patients (median 3%, range 0-69%) (P = 0.00006). There was no corelation with CD122 expression. Therefore, CD25 expression may serve as a surrogate marker for BCR/ABL positivity (Philadelphia chromosome), the major poor prognostic parameter in adult ALL. PMID- 9369423 TI - Three-color flow cytometry in the diagnosis of malignant lymphoma based on the comparative cell morphology of lymphoma cells and reactive lymphocytes. AB - This study examines the identification of unusual cell populations highly associated with lymphoma cells (UCP-L) in diagnostic biopsy specimens using three color flow cytometry (3-FCM). Patterns of surface antigen expression were used to compare the morphology of distinct lymphoid cell populations present in biopsy specimens and determine the presence or absence of UCP-L. UCP-L were identified by their larger size as compared to admixed reactive lymphocytes, and the method is based on the concept that neoplastic lymphoma cells are larger than reactive lymphocytes. The comparison of relative cell sizes was determined by overlaying forward scatter histograms by multicolor gating using PAINT-A-GATE software. In order for separate gates to be set on UCP-L and reactive cell populations, UCP-L had to fulfill one or more immunophenotypic criteria. These included: (1) belonging to a subset of B cell antigen-positive cells showing restricted expression of kappa or lambda light chains; (2) belonging to a subset of CD4 positive cells having dim or absent expression of CD45RA; (3) showing alterations in antigen expression (loss, dimmer or brighter); or (4) expressing an immunophenotype that is present on only rare cell populations or is absent from reactive lymph nodes. The immunophenotypic profiles of the respective cell populations were demonstrated by cubic representations to assess more easily the co-expression of three antigens. The common morphology of UCP-L as defined by forward and side scatter grams was consistent with a 'lymphoid appearance' except in several cases of HTLV-I-positive T cell lymphoma and gammadelta T cell lymphoma. The immunophenotypic profiles of UCP-L were confirmed to correspond to the presumptive lymphoma cell population by use of a live gating procedure on the large cells, which eliminated interference by reactive cells or necrotic tissue fragments. Using this method, we identified UCP-L in 208 of 293 (71%) consecutive cases of non-Hodgkin's lymphomas, while no UCP-L were seen in 72 cases of non specific hyperplasia of lymph nodes. Twenty-seven cases could not properly be examined about the existence of UCP-L because of massive necrosis, extensive fibrosis or strong non-specific staining reactions of unknown cause. When those cases were eliminated from the analysis, 80% of non-Hodgkin's lymphoma were found to contain UCP-L. In B cell lymphoma, the incidence of UCP-L in nodal lymphomas (80%) was much higher than in extranodal lymphomas (47%). Only one of 21 cases of Hodgkin's lymphoma was found to have UCP-L. The 3-FCM procedure was validated by the combined use of immunohistochemistry, morphologic examination, cytogenetic and antigen receptor gene rearrangement analysis by Southern blot hybridization. Our findings indicate that detection of UCP-L by 3-FCM is a reliable method to distinguish non-Hodgkin lymphomas from reactive hyperplasias in the majority of cases, even when the reactive cell population predominates over the malignant cell population. PMID- 9369424 TI - A functional study on the migration of human monocytes to human leukemic cell lines and the role of monocyte chemoattractant protein-1. AB - In the present study the migration of human monocytes towards the supernatants of five different human myeloid leukemic cell lines, four different human lymphatic leukemic cell lines and blasts derived from three different patients with acute myeloid leukemia (AML) was studied and the role of monocyte chemoattractant protein (MCP)-1 was established with an ELISA assay. Large differences in migration of monocytes towards the leukemic cell supernatants were shown (variation of approximately 10 to 150% compared to positive control), but high amounts of monocyte migration was always restricted to myeloid leukemic cells (cell lines or patient blasts). MCP-1 turned out to play a major role in the migration, firstly since there was a direct correlation between the amount of migration and the concentration of MCP-1 in the supernatants, and secondly since the addition of anti-hMCP-1 was able to inhibit migration to background level in all cases. Cytotoxicity experiments with a MTT test using MCP-1-stimulated monocytes against two human myeloid leukemic cell lines showed no increase in cell death compared to unstimulated monocytes. It is concluded that monocyte migration towards leukemic cells is restricted to the myeloid lineage and is regulated by MCP-1, which is produced in different amounts by the leukemic cells. Besides, MCP-1 does not increase the direct toxic effects of monocytes on leukemic cells. PMID- 9369425 TI - Analysis of residual disease in chronic lymphocytic leukemia by flow cytometry. AB - We have investigated the value of both conventional and quantitative flow cytometry to detect minimal residual disease in 21 CLL patients in remission including bone marrow histology: eight in complete remission (CR), 11 in nodular partial remission (nPR) and two in PR. The techniques used were double immunostaining with CD5 and CD19 and quantitative estimation of the number of both antigens with standard microbeads. Reference values were established on normal peripheral blood and bone marrow controls. Patients were considered in 'immunological' remission when the percentage of CD5+ CD19+/total CD19+ cells was <25% in PB and <15% in BM. In six of the eight patients in CR, CLL cells were still detectable by flow cytometry. Only two patients, that underwent allogeneic bone marrow transplant, achieved immunological remission. CLL samples showed significantly higher CD5 and lower CD19 antigen density than normal controls (P < 0.001). Persistence of residual disease was a predictor of time to progression. None of the two patients in immunological remission relapsed within a period of 13 and 33 months, whilst two of the six patients in CR with positive flow cytometry relapsed 3 and 6 months after achieving CR. This study demonstrates that flow cytometry contributes to increase the sensitivity of the clinicohematological criteria to detect residual malignant cells in CLL patients and may be useful to monitor disease status following treatment. PMID- 9369426 TI - Deletions and rearrangements of cyclin-dependent kinase 4 inhibitor gene p16 are associated with poor prognosis in B cell non-Hodgkin's lymphomas. AB - In the present study we examined by Southern blot analysis the presence of deletions and rearrangements of the p16 tumor-suppressor gene in B cell non Hodgkin's lymphomas (NHLs) in order to determine whether or not these changes can be related to a particular histological subtype and the different clinico biological and prognostic characteristics of the disease. 103 untreated patients were enrolled in the study. Seven cases displayed alterations in the p16 gene: four cases with homozygous deletions and three with gene rearrangement. The presence of these abnormalities did not correlate with any specific histological subtype: three cases were small lymphocytic lymphomas (two of them reclassified as mantle cell lymphoma on the basis of the REAL classification), two diffuse large cell lymphomas and two small non-cleaved cell lymphomas (one of them considered to be a Burkitt-like lymphoma according to the REAL). These seven cases showed a trend towards worse prognostic indicators than the remaining patients, and this was confirmed in the survival analysis, since the presence of p16 gene abnormalities was associated with a shorter survival (10 vs 81 months, P = 0.0006). In the multivariate analysis, p16 abnormalities were selected as an independent prognostic factor together with the LDH and beta2-microglobulin. These findings support a role for the p16 gene in the pathogenesis of B cell NHLs and suggest an association of p16 abnormalities with aggressive forms of the disease that could be useful to predict the prognosis of patients. PMID- 9369428 TI - Deletions at 11q identify a subset of patients with typical CLL who show consistent disease progression and reduced survival. AB - Eighty-four patients with typical chronic lymphocytic leukemia (CLL) (by morphological and immunophenotypic criteria) on whom karyotypes were available were studied. Binet stage at diagnosis and follow-up were defined. Survival was calculated from diagnosis. Fifty-one percent of patients had a karyotypic abnormality, the commonest being abnormalities at 13q14 (16%); these patients did not have significantly different survival from patients with normal karyotype. The second commonest abnormality was del(11q) (13%); these patients had significantly worse survival when compared both with patients with normal karyotype (P < 0.0001) and with other patients with karyotypic abnormality (P = 0.0012). All patients with del(11q) had progressed to stage C at follow-up while only 20% of the other patients had shown any disease progression (P < 0.0001). Del(11q) may identify a subset of patients with typical CLL who have worse survival and consistent disease progression and in future may help define a group of patients with CLL who could benefit from earlier or more intensive therapy. PMID- 9369427 TI - Normal Syk protein level but abnormal tyrosine phosphorylation in B-CLL cells. AB - One characteristic of B cells that accumulate during chronic lymphocytic leukemia (CLL) is their highly heterogeneous functional responses to B cell receptor (BCR) stimulation. Leukemic B cells with very poor responses have defective rapid tyrosine phosphorylation of numerous substrates, especially phospholipase C (PLC)gamma, as well as a defective calcium elevation on BCR stimulation. This points to a defect in BCR-associated protein tyrosine kinase (PTK). We investigated whether a defect in Syk, a PTK that is pivotal in coupling BCR to downstream signaling events, could account for these alterations. Syk tyrosine phosphorylation triggered by BCR ligation was severely impaired in B-CLL cells with low calcium responses to anti-mu stimulation. Syk associations were also defective, as concomitant tyrosine phosphorylation of a Syk-associated 145 kDa protein comigrating with PLCgamma-2 was only detected in responding B-CLL cells. By contrast, we found similar expression of the kinase regardless of B-CLL cell responsiveness. These results are consistent with the possibility that very proximal BCR signaling elements in some B-CLL cells are unable to connect with downstream biochemical events dominated by tyrosine phosphorylation and the potential docking function of Syk PTK. PMID- 9369429 TI - Chromosome aberrations in atypical chronic lymphocytic leukemia: a cytogenetic and interphase cytogenetic study. AB - To define better the chromosomal profile of atypical chronic lymphocytic leukemia (aCLL), cytogenetic and interphase cytogenetic studies were performed in 43 cases, using mitogen-stimulated cultures and DNA probes detecting the two most frequently occurring aberrations in CLL, ie +12 and 13q14 deletions. All cases showed monoclonal CD5/CD19-positive lymphocytosis, with more than 10% large lymphocytes and/or prolymphocytes in peripheral blood smears and reactivity with FMC7, or bright expression of surface immunoglobulins in a fraction of the cases. Karyotype aberrations were detected in 27 of 43 cases (62.8%). Recurrent chromosome changes were +12 (nine cases), 13q14 aberrations (five cases), 11q anomalies (three cases), 6q21-q23 abnormalities and 4q anomalies with different breakpoints (two cases each). Additional chromosome changes were seen in four cases with +12, in three cases with 13q14 anomalies, in two cases with 11q anomalies, in one case with 6q and 4q anomalies. Trisomy 12 was associated with 13q14 anomalies in three cases, one of which also had an 11q abnormality; other associations, found in one case each, were: 13q14 deletion with a 6q anomaly, 11q anomaly with 13q- and 7q-, a 6q anomaly with 7q- and +12. Interphase cytogenetics confirmed the results of chromosome banding analysis and showed that six patients with normal karyotype or no mitosis in fact had concomitant +12 and 13q14 deletion in four cases and isolated +12 or 13q14 deletion in one case each, with a resultant 76% overall incidence of cytogenetic abnormalities. The presence of +12, 13q14 deletions, 11q, and 6q21-q23 anomalies in 19 cases was associated with a 2-month median interval between diagnosis and start of treatment, as compared with a 24-month median interval in 14 cases with normal karyotype or non recurrent chromosome changes (P = 0.003). We conclude that aCLL is characterized by a relatively high incidence of chromosome anomalies, with recurrent chromosome changes, involving chromosomes 12, 13q14, 6q21q23, 11q, and, possibly, 4q. The presence of complex karyotypes, with concomitant abnormalities of 13q, +12, 6q, 11q, suggests that the development of sequential chromosome changes, rather than any single specific anomaly, may underlie leukemogenesis in this cytologic subset of CLL, partially accounting for the relatively aggressive clinical course. PMID- 9369430 TI - Establishment and characterization of a new erythropoietin-dependent acute myeloid leukemia cell line, AS-E2. AB - We have established an erythropoietin-dependent human leukemia cell line, AS-E2, from a patient with acute myeloid leukemia. These cells have many characteristics of late erythroid progenitor cells, they are positive for CD36, Glycophorin A, and CD71 but negative for CD41, and positive for benzidine and PAS staining. These cells express GATA-1 and have low affinity erythropoietin (EPO) receptor on their surface. Interestingly, AS-E2 cells are strictly dependent on EPO for their growth and survival; other cytokines including GM-CSF, stem cell factor, or IL-3 cannot support the growth of this cell line. These features are similar to late erythroid lineage cells, like normal BFU-E or CFU-E, and we have demonstrated that EPO stimulation induces the tyrosine phosphorylation of several proteins in AS-E2 cells including the EPO receptor and JAK2 kinase. This new cell line is a useful reagent to study biological and molecular events during the late stages of erythropoiesis, and to understand transforming events in human erythroid cells. PMID- 9369431 TI - Mutant AF-2 domain of PML-RARalpha in retinoic acid-resistant NB4 cells: differentiation induced by RA is triggered directly through PML-RARalpha and its down-regulation in acute promyelocytic leukemia. AB - To study the molecular mechanism of the differentiation induced by retinoic acid (RA) in acute promyelocytic leukemia (APL), we established a new RA-resistant NB4 subline, NB4/RA. The NB4/RA cells were neither differentiated by a single or a combination of RA isoforms, nor by the addition of clotrimazole (P450-inhibitor) or interferon gamma. However, the combination of RA and 8-(4-chlorophenylthio) adenosine cyclic 3',5'-monophosphate (a cAMP analog, 8-CPT-cAMP) induced differentiation. Immunostaining of NB4/RA cells using anti-PML antibody showed a microgranular pattern which was not restored even by the combination of RA and 8 CPT-cAMP, whereas the microgranular pattern in NB4 cells was rapidly restored to the normal speckled pattern by RA. Western blot analysis revealed that RA alone or the combination with 8-CPT-cAMP did not down-regulate PML-RARalpha in NB4/RA cells, which was in contrast to NB4 cells. The PML-RARalpha fusion gene and transcript in NB4/RA cells were conserved as well as the RARalpha gene and transcripts. Sequence analysis of the PML-RARalpha transcript in NB4/RA cells indicated a Pro (CCG) to Leu (CTG) mutation at codon 900 (type L) in AF-2 domain, while the RARalpha transcript had a normal sequence. These data suggest that differentiation of APL by RA is triggered directly through PML-RARalpha, and is associated with its degradation. Furthermore, there might be another mechanism of differentiation which does not require the down-regulation of PML-RARalpha and the restoration of the PML-staining pattern. PMID- 9369433 TI - The spectrum of chronic lymphoproliferative disorders in Hong Kong. A prospective study. AB - We report the incidence of the chronic lymphoproliferative disorders evolving with leukaemia in Hong Kong. Our findings demonstrate that B cell malignancies are significantly more frequent than mature T cell neoplasms, a picture similar to that seen in Western countries but different from other Eastern countries, eg Japan, where T cell malignancies are more frequent. In contrast to the West, where chronic lymphocytic leukaemia (CLL) is the most common disorder, in Hong Kong there is a clear predominance of B cell lymphomas in leukaemic phase accounting for two-thirds of the cases and particularly those displaying lymphoplasmacytic features or with villous lymphocytes. CLL in Hong Kong has similar clinical and laboratory features to the disease in patients from the West. Distinct disease categories, rare in the West such as the variant form of hairy cell leukaemia and T cell prolymphocytic leukaemia, are also documented. It is unclear whether the differences in prevalence of disease subtypes between Hong Kong and the West relate to different genetic background or environmental factors determinant of the development or progression of the leukaemia. Further studies investigating the genetic/molecular lesions may help to clarify whether the aetiopathogenesis of the lymphoid disorders in Hong Kong is similar to that of Western countries. PMID- 9369432 TI - Role of CDK4 and p16INK4A in interleukin-6-mediated growth of multiple myeloma. AB - Interleukin-6 (IL-6) promotes growth of human multiple myeloma (MM) cells via phosphorylation of retinoblastoma protein (pRB). We therefore examined the kinetics of cyclin-dependent kinase 4 (CDK4), p16INK4A, and pRB activation during IL-6-mediated patient MM cell growth compared with growth of IL-6 unresponsive patient plasma cell leukemia (PCL) cells. CDK4 protein was more strongly expressed in PCL cells than in MM cells. On the other hand, p16 protein was present in MM cells but undetectable in PCL cells. Interestingly, IL-6 induced peak proliferation of MM cells at days 1-3, with a return to baseline levels of DNA synthesis by days 6-9 in spite of replenishing IL-6. In these cells, IL-6 triggered a sustained increase in CDK4 by day 1 and a gradual increase in p16 to day 9. The progressive increase in p16 without further increments in CDK4 resulted in a shift from cyclin D2-CDK4/CDK6 binding at days 1-3 to p16-CDK4/CDK6 complex formation at days 6-9. Both phosphorylated pRB and dephosphorylated pRB were present initially in patient MM cells; IL-6 triggered a shift to phosphorylated pRB and G1 to S transition at days 1-3, with return to baseline levels of dephosphorylated pRB and related G1 growth arrest by day 9. No similar changes in CDK4, p16, or cell cycle profile were observed in IL-6 nonresponsive PCL cells. Our data therefore suggest a feedback mechanism in IL-6-mediated MM cell growth which is absent in IL-6 nonresponsive PCL cells. PMID- 9369434 TI - Deletions of chromosome 21 restricted to the leukemic cells of children with Down syndrome and leukemia. AB - Down syndrome (DS) is associated with an increased risk of developing hematological malignancies, but the basis for this predisposition is so far unknown. Using fluorescence in situ hybridization with a panel of locus-specific probes on normal and leukemic metaphases, we have found long-arm interstitial deletions of one of the chromosome 21s in the leukemic cells from five patients with DS and leukemia. This finding provides strong evidence for a gene or genes present on chromosome 21 having an important function in the development of leukemia in individuals with Down syndrome. PMID- 9369435 TI - Multiplex PCR for simultaneous detection of the most frequent T cell receptor delta gene rearrangements in childhood ALL. AB - A rapid and simple multiplex polymerase chain reaction (PCR) is described that is capable of identifying the six most frequent rearrangements of the T cell receptor (TCR)-delta gene segments in childhood acute lymphoblastic leukemia (ALL). The PCR products amplified in a single reaction are of different size for each TCR-delta gene rearrangement. Therefore, they are readily and unambiguously distinguished after agarose gel electrophoresis and assigned to a specific V-D-J gene rearrangement. There is no need for labor-intensive and time-consuming Southern blot hybridization or nested PCR. To evaluate the multiplex assay we chose 45 DNA samples of childhood ALL analyzed beforehand for TCR-delta gene rearrangements by Southern blot and single PCR of which 30 showed TCR-delta gene rearrangements. The multiplex PCR results corresponded to the Southern blot and single PCR analyses. The described multiplex PCR enables the detection of clonal markers in about 50% of patients in order to monitor minimal residual disease (MRD) in prospective studies with a high turnover of samples. PMID- 9369436 TI - CD3-CD4+ cells with a Th2-like pattern of cytokine production in the peripheral blood of a patient with cutaneous T cell lymphoma. AB - A case of cutaneous T cell lymphoma associated with mild eosinophilia and rise of IgE levels is reported. A population of CD3-CD4+ cells was observed in the peripheral blood. After activation, these purified CD3-CD4+ cells showed a Th2 pattern of cytokine production, secreting higher levels of IL-5 and IL-4 and lower levels of IFN-gamma compared to the patient's and controls' CD3+CD4+ cells. Moreover, high levels of IL-5 and soluble CD30, a marker of Th2 cell activation, were detected in the patient's serum. PMID- 9369438 TI - Pulmonary embolism in a patient with acute promyelocytic leukemia treated with all-trans retinoic acid. PMID- 9369437 TI - Burkitt's type acute lymphoblastic transformation associated with t(8;14) in a case of B cell chronic lymphocytic leukemia. PMID- 9369439 TI - Assessment of chimerism in sex-mismatched allogeneic bone marrrow transplants (allo-BMT) by in situ hybridization and cytogenetics. Is host cell percentage predictive of relapse? PMID- 9369440 TI - Secondary leukemia after autologous peripheral blood progenitor cell transplantation for breast cancer. PMID- 9369441 TI - Internal tandem duplication in the juxtatransmembrane domain of the flt3 is not involved in blastic crisis of chronic myeloid leukemia. PMID- 9369443 TI - Isolated chloroma of breast preceding acute nonlymphatic leukemia. PMID- 9369442 TI - Two Burkitt-type lymphoma/leukemia-derived cell lines presenting 3q27 translocations and immunoglobulin/BCL6 chimeric transcripts. PMID- 9369444 TI - Site-directed mutagenesis and yeast two-hybrid studies of the insulin and insulin like growth factor-1 receptors: the Src homology-2 domain-containing protein hGrb10 binds to the autophosphorylated tyrosine residues in the kinase domain of the insulin receptor. AB - To characterize the structural basis for the interaction between hGrb10 and the insulin receptor and the insulin-like growth factor-1 receptor, different mutant receptors containing a segment of deletion in either the juxtamembrane domain or in the C terminus of the receptors, or containing tyrosine-to-phenylalanine point mutations in these regions of the insulin receptor, were generated. Yeast two hybrid and in vitro binding studies of the interaction between the mutant receptors and hGrb10 revealed that tyrosine residues in these regions are not essential for the binding of hGrb10. To further identify the binding site for hGrb10, all conserved tyrosine residues in the kinase domain of the insulin receptor were replaced with either phenylalanine or alanine by site-directed mutagenesis. Mutations of all tyrosine residues in this region, except at positions 1162/1163, did not inhibit the binding of the receptor to hGrb10. The binding of the Src homology 2 domain of hGrb10 to the receptors was significantly enhanced in the presence of an intact pleckstrin homology domain. Our findings suggest that, unlike other Src homology 2 domain-containing proteins, hGrb10 binds to the autophosphorylated tyrosine residues in the kinase domain of the insulin receptor, and the pleckstrin homology domain plays an important role in hGrb10/receptor interaction. Because the autophosphorylated tyrosine residues are critical for the autophosphorylation and kinase activity of the receptor, the binding of hGrb10 at these sites may suggest a role for the protein in the transduction or regulation of insulin receptor signaling. PMID- 9369445 TI - Targeted expression of a dominant negative epidermal growth factor receptor in the mammary gland of transgenic mice inhibits pubertal mammary duct development. AB - The epidermal growth factor (EGF) system has been thought to play an important role in normal mammary development and carcinogenesis. To study the role of the EGF receptor (EGFR) in mammary development, we developed a transgenic mouse model in which a C-terminal truncated mouse EGFR (EGFR-TR) was expressed in the mouse mammary epithelium under the control of the mouse mammary tumor virus long terminal repeat. The EGFR-TR lacks most of the cytoplasmic domain of the receptor, including the entire protein tyrosine kinase domain. In cultured cells, we show that it acts in a dominant negative manner in EGF-signaled EGFR autophosphorylation. Several lines of mice were characterized and shown to express the transgene at the mRNA and protein levels not only in the mammary gland but also in the salivary glands, epididymis, and prostate. In postpubertal virgin female mice, the expression of the EGFR-TR in the mammary glands was greater than the expression of the endogenous wild type EGFR. In these virgin mice, inhibition in mammary ductal development and a decrease of mammary epithelial DNA synthesis were observed beginning at 5-6 weeks. The inhibition of duct development was most apparent by 15-16 weeks, resulting in a significant defect in ductal branching and outgrowth and an apparent overall decrease in the size of the mammary glands. However, during pregnancy, expression of the endogenous wild type EGFR was markedly increased relative to the EGFR-TR and, at this stage, normal presecretory alveoli developed from the hypoplastic duct tree. Postpartum, normal lactation occurred. Despite EGFR-TR expression in other tissues, no morphological abnormalities were observed. This model demonstrates that the EGFR-TR behaves as a dominant negative regulator of the EGFR system in vivo and that the EGFR system plays an important role in mammary ductal development. PMID- 9369447 TI - Identification of amino acids in the tau 2-region of the mouse glucocorticoid receptor that contribute to hormone binding and transcriptional activation. AB - The tau 2-region of steroid hormone receptors is a highly conserved region located at the extreme N-terminal end of the hormone-binding domain. A protein fragment encoding tau 2 has been shown to function as an independent transcriptional activation domain; however, because this region is essential for hormone binding, it has been difficult to determine whether the tau 2-region also contributes to the transactivation function of intact steroid receptors. In this study a series of amino acid substitutions were engineered at conserved positions in the tau 2-region of the mouse glucocorticoid receptor (mGR, amino acids 533 562) to map specific amino acid residues that contribute to the hormone-binding function, transcriptional activation, or both. Substitution of alanine or glycine for some amino acids (mutations E546G, P547A, and D555A) reduced or eliminated hormone binding, but the transactivation function of the intact GR and/or the minimum tau 2-fragment was unaffected for each of these mutants. Substitution of alanine for amino acid S561 reduced transactivation activity in the intact GR and the minimum tau 2-fragment but had no effect on hormone binding. The single mutation L550A and the double amino acid substitution L541G+L542G affected both hormone binding and transactivation. The fact that the S561A and L550A substitutions each caused a loss of transactivation activity in the minimum tau 2 fragment and the full-length GR indicated that the tau 2-region does contribute to the overall transactivation function of the full-length GR. Overall, the N terminal portion of the tau 2-region (mGR 541-547) was primarily involved in hormone binding, whereas the C-terminal portion of the tau 2-region (mGR 548-561) was primarily involved in transactivation. PMID- 9369446 TI - Msx1 is present in thyrotropic cells and binds to a consensus site on the glycoprotein hormone alpha-subunit promoter. AB - Our studies are aimed at identifying the transcription factors that activate the glycoprotein hormone alpha-subunit promoter. Therefore, we performed a Southwestern screening of a thyrotropic (alphaTSH) cDNA expression library, using the region of the promoter from -490 to -310 that contains sequences critical for expression in thyrotrope cells. A clone was isolated corresponding to part of the coding sequence of Msx1, which is a homeodomain-containing transcription factor that has been found to play an important role in the development of limb buds and craniofacial structures. Northern blot analysis, using the cloned Msx1 cDNA fragment as a probe, demonstrated that alpha-subunit-expressing thyrotrope cells (alphaTSH cells and TtT97 tumors) contained Msx1 RNA transcripts of 2.2 kb, while somatomammotrope (GH3) cells that do not produce the alpha-subunit had barely detectable levels. The presence of Msx1 protein was demonstrated by Western blot analysis in alphaTSH cells. We also demonstrated that transcripts encoding the closely related Msx2 factor were not detectable by Northern blot analysis in either thyrotrope or somatomammotrope-derived cells. Subfragments of the region from -490 to -310 of the alpha-subunit promoter were used in a Southwestern blot assay using bacterially produced Msx1 and demonstrated that binding was localized specifically to the region from -449 to -421. Deoxyribonuclease I protection analysis, using purified Msx1 homeodomain, demonstrated structurally induced differences in DNA digestion patterns between -436 and -413, and sequence analysis of this region revealed a direct repeat of the sequence GXAATTG, which is similar to the Msx1 consensus-binding site. When nucleotides at both sites were mutated, Msx1 binding was dramatically reduced, and the activity of an alpha subunit promoter construct decreased by approximately 50% in transfected thyrotrope (alphaTSH) cells. These studies suggest that Msx1 may play a role in the expression of the alpha-subunit gene in thyrotrope cells. PMID- 9369448 TI - Biochemical basis of partial nephrogenic diabetes insipidus phenotypes. AB - Biochemical properties of mutant type 2 vasopressin receptors (V2Rs) causing a partial phenotype of nephrogenic diabetes insipidus were investigated in transiently transfected HEK 293 cells. Cell surface expression of the V2R was not altered by substituting Asp85 in the second transmembrane region by Asn as determined by saturation binding assays. Although the affinity of the mutant V2R for arginine vasopressin (AVP) was reduced only 6-fold, the response of adenylyl cyclase activity to AVP revealed a 50-fold right shift in EC50 and a decreased maximum response for the mutant V2R. These data indicated that replacement of Asp85 by Asn affected coupling of the receptor to Gs, a conclusion substantiated by a 20-fold decrease in the calculated coupling efficiency of this receptor. The Gly201Asp mutation in the second extracellular loop, also found associated with an NDI partial phenotype, decreased cell surface expression of the V2R with minor reduction in ligand-binding affinity and coupling efficiency to Gs. A pronounced difference was observed for this mutant V2R between the stimulation of adenylyl cyclase activity promoted by AVP and the V2 vasopressin receptor agonist deamino[Cys1,D-Arg8]-vasopressin, suggesting an involvement of Gly201 in the selectivity of the receptor for different ligands. These data demonstrated that while decreased ligand-binding affinity and decreased coupling to Gs are responsible for the attenuation of response to ligand in the Asp85Asn mutant V2R, cell surface expression of the V2R is the major factor reducing cellular responses to ligand for the Gly201Asp mutant V2R. PMID- 9369449 TI - The tripartite basal enhancer of the gonadotropin-releasing hormone (GnRH) receptor gene promoter regulates cell-specific expression through a novel GnRH receptor activating sequence. AB - The molecular mechanisms regulating restricted expression of GnRH receptor and gonadotropin subunit genes to gonadotrope cells have been the focus of intense interest. Using deletion and mutational analysis we have identified a tripartite enhancer that regulates cell-specific expression of the GnRH receptor gene in the gonadotrope-derived alphaT3-1 cell line. Individual elements of this enhancer include binding sites for steroidogenic factor-1; activator protein 1 (AP-1); and a novel element referred to as the GnRH receptor activating sequence (GRAS). Mutation of each element alone results in loss of approximately 60% of promoter activity. Combinatorial mutations of any two elements decreases promoter activity by approximately 80%. Finally, mutation of all three elements reduces promoter activity to a level not different from promoterless vector. Using 2-bp mutations, we have defined the functional requirements for transcriptional activation by GRAS. The core motif of GRAS is at -391 to -380 bp relative to the start site of translation and has the sequence 5'-CTAGTCACAACA-3'. Three copies of GRAS or GRAS with a 2-bp mutation (muGRAS) were cloned into a luciferase expression vector immediately upstream of the thymidine kinase minimal promoter (TK) and tested for expression in alphaT3-1 cells. When compared with TK promoter alone, activity of 3xGRAS-TKLUC was increased by more than 5-fold while activity of 3xmuGRAS-TKLUC was unchanged. When 3xGRAS-TKLUC was transfected into a variety of nongo nadotrope cell lines, it did not increase activity of the TK promoter. We propose that basal activity of the GnRH receptor gene is regulated by a tripartite enhancer, and the key component of this enhancer is an element, GRAS, that activates transcription in a cell-specific fashion. PMID- 9369450 TI - Hepatocyte nuclear factor 1 and the glucocorticoid receptor synergistically activate transcription of the rat insulin-like growth factor binding protein-1 gene. AB - The insulin-like growth factor (IGF) binding proteins (IGFBPs) are a family of proteins that bind IGF-I and IGF-II and modulate their biological activities. IGFBP-1 is distinctive among the IGFBPs in its rapid regulation in response to metabolic and hormonal changes. The synthetic glucocorticoid, dexamethasone, increases IGFBP-1 mRNA abundance and gene transcription in rat liver and in H4-II E rat hepatoma cells. A glucocorticoid response element (GRE) located at nucleotide (nt) -91/-77 is required for dexamethasone to stimulate rat IGFBP-1 promoter activity in transient transfection assays in H4-II-E cells. In addition to the GRE, three accessory regulatory sites [a putative hepatocyte nuclear factor-1 (HNF-1) site (nt -62/-50), an insulin-response element (nt -108/-99), and an upstream site (nt -252/-236)] are involved in dexamethasone stimulation under some, but not all, circumstances. The present study begins to address the mechanism by which transcription factors bound to the putative HNF-1 site act synergistically with the glucocorticoid receptor (GR) bound to the GRE. In gel shift assays, HNF-1alpha and HNF-1beta in H4-II-E extracts bind to the palindromic HNF-1 site. Both half-sites are required. Overexpression of HNF-1beta enhances dexamethasone-stimulated promoter activity. Both the HNF-1 site and the GRE must be intact for stimulation to occur. By contrast, overexpression of HNF 1alpha does not enhance dexamethasone-stimulated promoter activity, although, as also observed with overexpression of HNF-1beta, it inhibits basal promoter activity. Thus, the synergistic effects of HNF-1beta and the GR on dexamethasone stimulated promoter activity require that they are bound to the HNF-1 site and the GRE, respectively, and may involve protein-protein interactions between the transcription factors, or between them and the basal transcription machinery or a steroid receptor coactivator. Synergy between the ubiquitously expressed GR and HNF-1, which is developmentally regulated and expressed in a limited number of tissues, provides a possible mechanism for tissue- and development-specific regulation of glucocorticoid action. PMID- 9369451 TI - Osteogenic protein-1 up-regulation of the collagen X promoter activity is mediated by a MEF-2-like sequence and requires an adjacent AP-1 sequence. AB - Bone morphogenetic proteins induce chondrogenesis and osteogenesis in vivo. To investigate molecular mechanisms involved in chondrocyte induction, we examined the effect of osteogenic protein (OP)-1/bone morphogenetic protein-7 on the collagen X promoter. In rat calvaria-derived chondrogenic C5.18 cells, OP-1 up regulates collagen X mRNA levels and its promoter activity in a cell type- specific manner. Deletion analysis localizes the OP-1 response region to 33 bp ( 310/-278), which confers OP-1 responsiveness to both the minimal homologous and heterologous Rous sarcoma virus promoter. Transforming growth factor-beta2 or activin, which up-regulates the expression of a transforming growth factor-beta inducible p3TP-Lux construct, has little effect on collagen X mRNA and on this 33 bp region. Mutational analysis shows that both an AP-1 like sequence (-294/-285, TGAATCATCA) and an A/T-rich myocyte enhancer factor (MEF)-2 like sequence (-310/ 298, TTAAAAATAAAAA) in the 33-bp region are necessary for the OP-1 effect. Gel shift assays show interaction of distinct nuclear proteins from C5.18 cells with the AP-1-like and the MEF-2-like sequences. OP-1 rapidly induces nuclear protein interaction with the MEF-2-like sequence but not with the AP-1 like sequence. MEF 2-like binding activity induced by OP-1 is distinct from the MEF-2 family proteins present in C2C12 myoblasts, in which OP-1 does not induce collagen X mRNA or up-regulate its promoter activity. In conclusion, we identified a specific response region for OP-1 in the mouse collagen X promoter. Mutational and gel shift analyses suggest that OP-1 induces nuclear protein interaction with an A/T-rich MEF-2 like sequence, distinct from the MEF-2 present in myoblasts, and up-regulates collagen X promoter activity, which also requires an AP-1 like sequence. PMID- 9369452 TI - A novel neuroendocrine intracellular signaling pathway. AB - Expression of many components of the secretory pathway in peptidergic neuroendocrine cells is precisely controlled in response to secretagogues. Regulated endocrine-specific protein (RESP18) was identified as a dopamine regulated intermediate pituitary transcript. Although the amino acid sequence of RESP18 initially suggested that it might be a novel preprohormone, its widespread expression in peptide-producing neurons and endocrine cells and its localization to the lumen of the endoplasmic reticulum suggested that it subserves a unique function. Subtractive hybridization of a pituitary corticotrope AtT-20 cell line engineered for inducible RESP18 expression demonstrated a RESP18-dependent induction of several transcripts. Regulation of RESP18 expression in vitro and in vivo was accompanied by changes in the same transcripts. Several cDNAs encoding transcripts up-regulated by RESP18 were analyzed by DNA sequencing, searching the GenBank databases for homologous proteins, and Northern blotting. One novel clone showed a tissue distribution nearly identical to that of RESP18. One clone was identical to rat LIMK2, a protein kinase containing modular protein-protein interaction LIM (lin-11, isl-1, mec-3) domains. Another clone was similar to monomeric bacterial isocitrate dehydrogenases. Like the unfolded protein response, these data demonstrate a novel signaling pathway from the secretory pathway lumen to the nucleus. RESP18 acts as a lumicrine peptide (an intracellular luminal autocrine hormone) inducing this pathway. PMID- 9369453 TI - Interference of BAD (Bcl-xL/Bcl-2-associated death promoter)-induced apoptosis in mammalian cells by 14-3-3 isoforms and P11. AB - Apoptosis and survival of diverse cell types are under hormonal control, but intracellular mechanisms regulating cell death are unclear. The Bcl-2/Ced-9 family of proteins contains conserved Bcl-2 homology regions that mediate the formation of homo- or heterodimers important for enhancing or suppressing apoptosis. Unlike most other members of the Bcl-2 family, BAD (Bcl-xL/Bcl-2 associated death promoter), a death enhancer, has no C-terminal transmembrane domain for targeting to the outer mitochondrial membrane and nuclear envelope. We hypothesized that BAD, in addition to binding Bcl-xL and Bcl-2, may interact with proteins outside the Bcl-2 family. Using the yeast two-hybrid system to search for BAD-binding proteins in an ovarian fusion cDNA library, we identified multiple cDNA clones encoding different isoforms of 14-3-3, a group of evolutionally conserved proteins essential for signal transduction and cell cycle progression. Point mutation of BAD in one (S137A), but not the other (S113A), putative binding site found in diverse 14-3-3 interacting proteins abolished the interaction between BAD and 14-3-3 without affecting interactions between BAD and Bcl-2. Because the S137A BAD mutant presumably resembles an underphosphorylated form of BAD, we used this mutant to screen for additional BAD-interacting proteins in the yeast two-hybrid system. P11, a nerve growth factor-induced neurite extension factor and member of the calcium-binding S-100 protein family, interacted strongly with the mutant BAD but less effectively with the wild type protein. In Chinese hamster ovary (CHO) cells, transient expression of wild type BAD or its mutants increased apoptotic cell death, which was blocked by cotransfection with the baculovirus-derived cysteine protease inhibitor, P35. Cotransfection with 14-3-3 suppressed apoptosis induced by wild type or the S113A mutant BAD but not by the S137A mutant incapable of binding 14-3-3. Furthermore, cotransfection with P11 attenuated the proapoptotic effect of both wild type BAD and the S137A mutant. For both 14-3-3 and P11, direct binding to BAD was also demonstrated in vitro. These results suggest that both 14-3-3 and P11 may function as BAD-binding proteins to dampen its apoptotic activity. Because the 14 3-3 family of proteins could interact with key signaling proteins including Raf-1 kinase, protein kinase C, and phosphatidyl inositol 3 kinase, whereas P11 is an early response gene induced by the neuronal survival factor, nerve growth factor, the present findings suggest that BAD plays an important role in mediating communication between different signal transduction pathways regulated by hormonal signals and the apoptotic mechanism controlled by Bcl-2 family members. PMID- 9369454 TI - Molecular and kinetic basis for the mixed agonist/antagonist activity of estriol. AB - Estriol acts as a weak estrogen when administered in a single dose into immature or ovariectomized laboratory animals, but produces full estrogenic responses upon chronic administration. However, when estriol is injected together with estradiol it acts as an antiestrogen. We studied the dual agonist/antagonist properties of estriol, using recombinant human estrogen receptor (hER) in ligand-binding assay, cell-free transcription assay, electrophoretic mobility shift assay with cVitII estrogen response element (ERE), and ERE-Sepharose chromatography. We show that the weak estrogenic activity of estriol results from impaired hER-ERE interaction. The antiestrogenic activity of estriol was demonstrated in a cell free transcription assay where it reduced estradiol-dependent transcription in a dose-dependent manner. Estriol interfered with estradiol-induced positive cooperative binding and receptor dimerization, and binding of hER complexes to ERE. These effects of estriol were maximal at a 10-fold molar excess over estradiol; under these conditions estradiol-dependent transcription was decreased by 85%, although [3H]estradiol binding was reduced by only 50%. We propose that when hER, estradiol, and estriol are coequilibrated, several receptor species are formed: unliganded hER monomers and dimers; estradiol-hER monomers and dimers, estriol-hER monomers and dimers; and presumably mixed estradiol-estriol dimers. Since estrogen-hER complexes bind cooperatively to ERE sequences, the concentrations of transcriptionally active complexes (estriol- and estradiol-hER dimers) are reduced to low levels that fail to bind cooperatively with ERE and initiate transcription. We discuss our results in relation to the massive estriol production during pregnancy and to the "Estriol Hypothesis" on the protective role for estriol in opposing carcinogenic effects of estradiol. PMID- 9369455 TI - An introduction to birdsong and the avian song system. PMID- 9369456 TI - Three models of song learning: evidence from behavior. AB - Research on avian song learning has traditionally been based on an instructional model, as exemplified by the sensorimotor model of song development. Several large-scale, species-wide field studies of learned birdsongs have revealed that variation is narrowly restricted to certain aspects of song structure. Other aspects are sufficiently stereotyped and so widely shared by species' members that they qualify as species-specific universals. The limitations on natural song variation are difficult to reconcile with a fully open, instructive model of song learning. An alternative model based on memorization by selection postulates a system of innate neural templates that facilitate the recognition and rapid memorization of conspecific song patterns. Behavioral evidence compatible with this model includes learning preferences, rapid conspecific song learning, and widespread ocurrence of species-specific song universals that are recognized innately but fail to develop in songs of social isolates. A third model combines instruction, in the memorization phase, with selection during song production. An overproduced repertoire of plastic songs previously memorized by instruction is winnowed by selection imposed during social interactions at the time of adult song crystallization. Selection during production is well established as a factor in the song development of several species, in the form of action-based learning. The possible role of selective processes in song memorization merits further neurobiological investigation. PMID- 9369457 TI - Comparative approaches to the avian song system. AB - There is extensive diversity among the 4000 species of songbirds in different aspects of song behavior, including the timing of vocal learning, sex patterns of song production, number of songs that are learned (i.e., repertoire size), and seasonality of song behavior. This diversity provides unparalleled opportunities for comparative studies of the relationship between the structure and function of brain regions and song behavior. The comparative approach has been used in two contexts: (a) to test hypotheses about mechanisms of song control, and (b) to study the evolution of the control system in different groups of birds. In the first context, I review studies in which a comparative approach has been used to investigate sex differences in the song system, the relationship between the number of song types a bird sings and the size of the song nuclei, and seasonal plasticity of the song control circuits. In the second context, I discuss whether the vocal control systems of parrots and songbirds were inherited from a common ancestor or independently evolved. I also consider at what stage in the phylogeny of songbirds the hormone-sensitive forebrain circuit found in modern birds first evolved. I conclude by identifying directions for future research in which a comparative approach would be productive. PMID- 9369458 TI - Anatomical and synaptic substrates for avian song learning. AB - In songbirds, vocal learning occurs during periods of major cellular and synaptic change. This neural reorganization includes massive synaptogenesis associated with the addition of new neurons into the vocal motor pathway, as well as pruning of connections between song regions. These observations, coupled with behavioral evidence that song development requires NMDA receptor activation in specific song nuclei, suggest that experiences associated with vocal learning are encoded by activity driven, Hebbianlike processes of synaptic change akin to those implicated in many other forms of developmental plasticity and learning. In this review we discuss the hypothesis that develpmental and/or seasonal changes in NMDA receptor function and the availability of new synapses may modulate thresholds for plasticity and thereby define sensitive periods for vocal learning. PMID- 9369459 TI - Role of gene regulation in song circuit development and song learning. AB - The songbird has emerged as an important model for study of brain-behavior relationships by virtue of its rich natural advantages and from the pioneering efforts of explorers using anatomical and behavioral approaches. Now, molecular biology is providing a new and complementary paradigm for discerning songbird brain organization and function. Here, I review the work over the last 10 years that has laid the foundation for approaching songbird biology from the molecular perspective. As a result of this work, specific hypotheses can now be framed and tested regarding the mechanisms behind song circuit formation, behavioral plasticity, and the boundaries of adaptability. Age-related changes in more than 15 molecules have been observed in the song system of juvenile zebra finches, and these changes seem to define specific phases in circuit development. In adult songbirds, ordinary song-related activities such as singing and listening cause dramatic increases in gene expression in brain areas specific to each activity. The sensitivity of gene activation is modulated as a result of experience in adulthood and also changes during juvenile song learning. These studies have provided unexpected insights into the functional organization of the song circuit and the potential role of extrinsic modulatory systems in directing and limiting plastic change in the brain. With this rich base of knowledge, and techniques of gene manipulation on the horizon, answers to old questions seem within our reach: What sets the boundaries of neural plasticity? What limits learning? PMID- 9369460 TI - Sexual differentiation of the zebra finch song system: positive evidence, negative evidence, null hypotheses, and a paradigm shift. AB - Permanent sex differences in the brain are found in many vertebrates, and are thought to be induced by sex differences in secretion of gonadal steroid hormones during critical periods of early development. This theory has received support primarily from many experiments conducted on mammals, but also from studies on other vertebrate classes, including birds. The only avian neural dimorphism that has allowed extensive tests of this hypothesis is the neural circuit for song in passerine birds, which is much larger in males than in females. Experiments in zebra finches have yielded contradictory results. Although it is relatively easy to induce masculine patterns of development in genetic females with estrogen, it has not been possible to induce feminine patterns of development in males with any treatments, including antiestrogens and inhibitors of estrogen synthesis. Moreover, genetic females that develop with large amounts of functional testicular tissue but with virtually no ovarian tissue nevertheless have a feminine song circuit. The latter studies fail to support the idea of steroid induction of sexual differentiation. An alternative to the steroidal control hypothesis is that nonhormonal gene products expressed in the brain early in development trigger sexually dimorphic patterns of development. Although current evidence in several neural and nonneural systems indicates that sexual differentiation of some somatic phenotypes cannot be explained by the actions of gonadal steroids, the idea of direct genetic (nonhormonal) induction of sexual differentiation has yet to be proved. PMID- 9369461 TI - Birth, migration, incorporation, and death of vocal control neurons in adult songbirds. AB - Neurogenesis continues in the brain of adult birds. These cells are born in the ventricular zone of the lateral ventricles. Young neurons then migrate long distances guided, in part, by radial cell processes and become incorporated throughout most of the telencephalon. In songbirds, the high vocal center (HVC), which is important for the production of learned song, receives many of its neurons after hatching. HVC neurons which project to the robust nucleus of the archistriatum to form part of the efferent pathway for song production, and HVC interneurons continue to be added throughout life. In contrast, Area X-projecting HVC cells, thought to be part of a circuit necessary for song learning but not essential for adult song production, are only born in the embryo. New neurons in HVC of juvenile and adult birds replace older cells that die. There is a correlation between seasonal cell turnover rates (addition and loss) and testosterone levels in adult male canaries. Available evidence suggests that steroid hormones control the recruitment and/or survival of new HVC neurons, but not their production. The functions of neuronal replacement in adult birds remain unclear. However, rates of HVC neuron turnover are highest at times of year when canaries modify their songs. Replaceable HVC neurons may participate in the modification of perceptual memories or motor programs for song production. In contrast, permanent HVC neurons could hold long-lasting song-related information. The unexpected large-scale production of neurons in the adult brain holds important clues about brain function and, in particular, about the neural control of a learned behavior--birdsong. PMID- 9369462 TI - Circuits, hormones, and learning: vocal behavior in songbirds. AB - Species-typical vocal patterns subserve species identification and communication for individual organisms. Only a few groups of organisms learn the sounds used for vocal communication, including songbirds, humans, and cetaceans. Vocal learning in songbirds has come to serve as a model system for the study of brain behavior relationships and neural mechanisms of learning and memory. Songbirds learn specific vocal patterns during a sensitive period of development via a complex assortment of neurobehavioral mechanisms. In many species of songbirds, the production of vocal behavior by adult males is used to defend territories and attract females, and both males and females must perceive vocal patterns and respond to them. In both juveniles and adults, specific types of auditory experience are necessary for initial song learning as well as the maintenance of stable song patterns. External sources of experience such as acoustic cues must be integrated with internal regulatory factors such as hormones, neurotransmitters, and cytokines for vocal patterns to be learned and produced. Thus, vocal behavior in songbirds is a culturally acquired trait that is regulated by multiple intrinsic as well as extrinsic factors. Here, we focus on functional relationships between circuitry and behavior in male songbirds. In that context, we consider in particular the influence of sex hormones on vocal behavior and its underlying circuitry, as well as the regulatory and functional mechanisms suggested by morphologic changes in the neural substrate for song control. We describe new data on the architecture of the song system that suggests strong similarities between the songbird vocal control system and neural circuits for memory, cognition, and use-dependent plasticity in the mammalian brain. PMID- 9369463 TI - Sex steroids and their actions on the birdsong system. AB - It is probably not surprising to most of us that the endocrine system plays a significant role in controlling the singing behavior of birds. We are familiar with the song of birds as a conspicuous acoustic feature of our environment during the avian breeding season. We often witness song when it is produced by birds (males) that are aggressively establishing and defending territories and that are advertising to available females. Thus, it is easy to imagine that song is likely to be stimulated by gonadal hormones. However, the ways in which gonadal sex steroids influence the various parts of the brain at various stages of the bird's life to influence song are complex and far from being completely understood. In this review, I will highlight some of the significant discoveries that have contributed to our view that the songbird brain is a significant and dynamic target of sex steroids. I will also describe what we have learned about properties of the endocrine system and the brain and how they each contribute to making androgens or estrogens available to particular parts of the songbird brain. Finally, I will describe some new research directions that may help answer some unresolved issues about hormonal effects on the songbird brain. PMID- 9369464 TI - Peripheral control and lateralization of birdsong. AB - Recent studies on several species of oscine songbirds show that they achieve their varied vocal performances through coordinated activity of respiratory, syringeal, and other vocal tract muscles in ways that take maximum advantage of the acoustic flexibility made possible by the presence of two independently controlled sound sources in their bipartite syrinx (vocal organ). During song, special motor programs to respiratory muscles alter the pattern of ventilation to maintain the supply of respiratory air and oxygen to permit songs of long duration, high syllable repetition rates, or maximum spectral complexity. Each side of the syrinx receives its own motor program that, together with that sent to respiratory muscles, determines the acoustic properties of the ipsilaterally produced sound. The acoustic expression of these bilaterally distinct, phonetic motor patterns depends on the action of dorsal syringeal adductor muscles that, by opening or closing the ipsilateral side of the syrinx to airflow, determine the amount each side contributes to song. The syringeally generated sound is further modified by muscles that control the shape of the vocal tract. Different species have adopted different motor strategies that use the left and right sides of the syrinx in patterns of unilateral, bilateral, alternating, or sequential phonation to achieve the differing temporal and spectral characteristics of their songs. As a result, the degree of song lateralization probably varies between species to form a continuum from unilateral dominance to bilateral equality. PMID- 9369465 TI - Neural pathways for the control of birdsong production. AB - As in humans, song production in birds involves the intricate coordination of at least three major groups of muscles: namely, those of the syrinx, the respiratory apparatus, and the upper vocal tract, including the jaw. The pathway in songbirds that controls the syrinx originates in the telencephalon and projects via the occipitomesencephalic tract directly upon vocal motoneurons in the medulla. Activity in this pathway configures the syrinx into phonatory positions for the production of species typical vocalizations. Another component of this pathway mediates control of respiration during vocalization, since it projects upon both expiratory and inspiratory groups of premotor neurons in the ventrolateral medulla, as well as upon several other nuclei en route. This pathway appears to be primarily involved with the control of the temporal pattern of song, but is also importantly involved in the control of vocal intensity, mediated via air sac pressure. There are extensive interconnections between the vocal and respiratory pathways, especially at brain-stem levels, and it may be these that ensure the necessary temporal coordination of syringeal and respiratory activity. The pathway mediating control of the jaw appears to be different from those mediating control of the syrinx and respiratory muscles. It originates in a different part of the archistriatum and projects upon premotor neurons in the medulla that appear to be separate from those projecting upon the syringeal motor nucleus. The separateness of this pathway may reflect the imperfect correlation of jaw movements with the dynamic and acoustic features of song. The brainstem pathways mediating control of vocalization and respiration in songbirds have distinct similarities to those in mammals such as cats and monkeys. However, songbirds, like humans, but unlike most other non-songbirds, have developed a telencephalic vocal control system for the production of learned vocalizations. PMID- 9369466 TI - Functional organization of forebrain pathways for song production and perception. AB - This article reviews the organization of the forebrain nuclei of the avian song system. Particular emphasis is placed on recent physiologic recordings from awake behaving adult birds while they sing, call, and listen to broadcasts of acoustic stimuli. The neurons in the descending motor pathway (HVc and RA) are organized in a hierarchical arrangement of temporal units of song production, with HVc neurons representing syllables and RA neurons representing notes. The nuclei Uva and NIf, which are afferent to HVc, may help organize syllables into larger units of vocalization. HVc and RA are also active during production of all calls. The patterns of activity associated with calls differ between learned calls and those that are innately specified, and give insight into the interactions between the forebrain and midbrain during calling, as well as into the evolutionary origins of the song system. Neurons in Area X, the first part of the anterior forebrain pathway leading from HVc to RA, are also active during singing. Many HVc neurons are also auditory, exhibiting selectivity for learned acoustic parameters of the individual bird's own song (BOS). Similar auditory responses are also observed in RA and Area X in anesthetized birds. In contrast to HVc, however, auditory responses in RA are very weak or absent in awake birds under our experimental paradigm, but are uncovered when birds are anesthetized. Thus, the roles of both pathways beyond HVc in adult birds is under review. In particular, theories hypothesizing a role for the descending motor pathway (RA and below) in adult song perception do not appear to obtain. The data also suggest that the anterior forebrain pathway has a greater motor role than previously considered. We suggest that a major role of the anterior forebrain pathway is to resolve the timing mismatch between motor program readout and sensory feedback, thereby facilitating motor programming during birdsong learning. Pathways afferent to HVc may participate more in sensory acquisition and sensorimotor learning during song development than is commonly assumed. PMID- 9369467 TI - Song- and order-selective neurons develop in the songbird anterior forebrain during vocal learning. AB - The anterior forebrain (AF) pathway of songbirds has an essential but poorly understood function during song learning, a process requiring auditory experience. Consistent with a role in processing auditory information, two nuclei of the AF, the lateral magnocellular nucleus of the anterior neostriatum (IMAN) and Area X (X), contain some of the most complex auditory neurons known. In adult zebra finches, these neurons are strongly selective for both spectral and temporal properties of song: They respond more robustly to the bird's own song (BOS) than to songs of conspecific individuals, and they respond less well to BOS if it is played in reverse. IMAN and X neurons of young finches early in the process of song learning (30-45 days of age) are also song responsive, but lack the song and order selectivity present in adult birds. By an intermediate stage of learning (60 days), when birds have experience of both tutor song and their own developing (plastic) song, AF neurons have significant song and order selectivity for both tutor song and BOS (in this case, plastic song). The degree of BOS selectivity is still less than that found in adults, however. In addition, neurons at 60 days are heterogenous in their preference for BOS versus tutor song: Most prefer BOS, some prefer tutor song, and others respond equally to both songs. The selectivity of adult AF auditory neurons therefore arises rapidly during development in neurons that are initially unselective. These neurons are one of the clearest examples of experience-dependent acquisition of complex stimulus selectivity. Moreover, the neural selectivity for both BOS and tutor song at 60 days raises the possibility that experience of both songs during learning contributes to the properties of individual AF neurons. PMID- 9369468 TI - Mercury-sensitive residues and pore site in AQP3 water channel. AB - Water channel function of all aquaporins (AQPs) but AQP4 can be inhibited by mercurial reagents. Mercurial reagents are believed to bind specifically to cysteine residues and block the aqueous pore of AQPs. Because of the low homology of AQP3 to other AQPs, it is not certain whether the pore structure of AQP3 is similar to that of the others. Determination of mercury-sensitive cysteine residues in AQP3 and comparison with those in other AQPs will help to resolve this question. When AQP3 was expressed in Xenopus oocytes, incubation with 0.3 mM HgCl2 decreased its osmotic water permability (Pf) by approximately 30%. To identify the mercury-sensitive site, six individual cysteine residues in human AQP3 (at positions 11, 29, 40, 91, 174, and 267) were altered by site-directed mutagenesis. Mutants of C11S and C11A had a similar basal Pf to wild-type but acquired mercury resistance. Replacement of Cys-11 with Trp, which possesses a large side chain, did not change Pf. Mercurial inhibition of Pf was still observed in five other Cys-to-Ser mutants. These results suggest that Cys-11 is the mercury-sensitive residue in AQP3 and that this residue might be independent of water channel function. Mutation of Tyr-212, a position corresponding to the mercury-sensitive residues in AQP1 and AQP2, to cysteine enhanced the mercurial inhibition of Pf. Y212W had no water channel activity. Expression of AQP3 increased glycerol permeability (Pgly) 3.1-fold, whereas Pgly of Y212W-expressing oocytes was similar to Pgly of control oocytes. Cysteine mutation at Tyr-212 increased the inhibitory effect of mercury on Pgly. These results suggest that the structure of the aqueous pore of AQP3 resembles those of AQP1 and AQP2 and support the hypothesis that water and small molecules share a common pore in AQP3. PMID- 9369469 TI - Human thioredoxin homodimers: regulation by pH, role of aspartate 60, and crystal structure of the aspartate 60 --> asparagine mutant. AB - Thioredoxins are a group of ca. 12 kDa redox proteins that mediate numerous cytosolic processes in all cells. Human thioredoxin can be exported out of the cell where it has additional functions including the ability to stimulate cell growth. A recent crystal structure determination of human thioredoxin revealed an inactive dimeric form of the protein covalently linked through a disulfide bond involving Cys 73 from each monomer [Weichsel et al. (1996) Structure 4, 735-751]. In the present study, apparent dissociation constants (Kapp) for the noncovalently linked dimers were determined at various pHs using a novel assay in which preformed dimers, but not monomers, were rapidly linked through oxidation (with diamide) of the Cys 73 disulfide bond, and the relative amounts of monomer and dimer were detected by gel filtration. The values obtained were pH-dependent, varying between 6.1 and 166 microM for the pH range of 3.8-8.0, and were consistent with the titration of a single ionizable group having a pKa of 6.5. A similar value was obtained using gel filtration at pH 3.8 (Kapp = 164 microM), and the crystal structure of the diamide-oxidized protein was determined to be nearly identical to that obtained in the absence of diamide. Asp 60 lies in the dimer interface and was found to be responsible for the pH dependence for dimer formation, and therefore must have a pKa elevated by approximately 2.5 pH units. Mutation of Asp 60 to asparagine abolished nearly all of the pH dependence for dimer formation. The crystal structure of the D60N mutant revealed a dimer nearly identical to the wild type, but, surprisingly, it had the Asn 60 side chain rotated out of the dimer interface and replaced with two water molecules. The values obtained for Kapp suggest human thioredoxin may dimerize in vivo and possible roles for such dimers are discussed. PMID- 9369470 TI - Structure of an RNA hairpin loop with a 5'-CGUUUCG-3' loop motif by heteronuclear NMR spectroscopy and distance geometry. AB - Structural features of a 19-nucleotide RNA hairpin loop (5'-GGCGUACGUUUCGUACGCC 3'), a loop motif which occurs in eukaryotic 18S rRNA, have been derived using multidimensional heteronuclear NMR spectroscopy in combination with local conformational analysis and torsion angle distance geometry followed by restrained energy minimization. A method to obtain both the 3JC4'P3' and 3JC4'P5' coupling constants from a set of spin-echo difference constant time HSQC spectra is introduced, and it is shown how these couplings can be assigned to the backbone angles beta and epsilon. A total of 280 distance constraints as well as 132 homo- and heteronuclear three-bond scalar coupling constants were derived from the NMR data. The structure which has been determined is a pentaloop rather than a triloop with no base pairing between G8 and C12. G8 is pointed to the minor groove where it forms a base triplet with C7-G13 that is further stabilized by hydrogen bonding to the 2'-hydroxyl group of C7. C12 is directed to the major groove where its conformation is stabilized by hydrogen bonding between O2 and HO2'. The NMR data suggest two possible, interconverting conformations with stacking of bases U10-G8 or U11-C7. Overall, the loop provides a variety of interaction sites for RNA or protein interactions. PMID- 9369471 TI - Paramagnetic cobalt as a probe of the orientation of an accessory DNA-binding region of the yeast ADR1 zinc-finger protein. AB - The minimal DNA-binding domain of the yeast ADR1 transcription factor consists of two Cys2-His2 zinc fingers and an additional 20 residues N-terminal and proximal to the fingers. The accessory sequence likely plays a role in contacting DNA. Paramagnetic cobalt was incorporated into the fingers of an ADR1 DNA-binding construct (ADR1z) to serve as a probe of the proximity of the accessory sequence to the zinc fingers. NMR signals from the accessory region are not perturbed by cobalt incorporation. Previous studies showed that this region is random coil in the ADR1z construct in the absence of DNA; it does not adopt a fixed orientation with respect to the cobalt sites. In contrast, many residues of the accessory region are perturbed by cobalt in the DNA-bound form of the protein, suggesting this region becomes constrained. This observation agrees with previous results showing a disorder-to-order transition for the accessory region upon DNA binding. Furthermore, these results indicate that the accessory region lies close to the fingers in the protein-DNA complex. This region thus does not extend along the DNA away from the zinc fingers; it more likely binds the same stretch of DNA contacted by the zinc fingers. Comparison to the behavior of other zinc-finger proteins that utilize an accessory DNA-binding sequence suggested that the region of ADR1 proximal to the zinc fingers might form an alpha-helix. Analysis of sequential NOEs in the accessory region of DNA-bound ADR1z reveals no helical structure. PMID- 9369472 TI - Structural comparison of the enzymatically active and inactive forms of delta crystallin and the role of histidine 91. AB - The major soluble protein component of avian and reptilian eye lenses, delta crystallin, is highly homologous to the urea cycle enzyme, argininosuccinate lyase (ASL). In duck lenses there are two highly homologous delta crystallins, termed delta I and delta II, that are 94% identical in amino acid sequence. While delta II crystallin has been shown to exhibit ASL activity in vitro, delta I crystallin is inactive. The X-ray structure of a His to Asn mutant of duck delta II crystallin (H91N) has been determined to 2.5 A resolution using the molecular replacement technique. The overall fold of the protein is similar to other members of the superfamily to which this protein belongs, with the active site located in a cleft between three different monomers of the tetrameric protein. A reexamination of the kinetic properties of the H91N mutant reveals that the mutant has 10% wild-type activity. The Vmax of the mutant protein is identical to that of the wild-type protein, but a 10-fold increase in the Michaelis constant is seen, suggesting that His 91 is involved in binding the substrate. In an effort to determine the reasons for the loss of enzymatic activity in delta I crystallin, a structural comparison of the H91N mutant with the enzymatically inactive turkey delta I crystallin has been performed. This study revealed a remarkable similarity in the overall structures of the two proteins. Three regions of secondary structure do differ significantly between the two models; these include the N-terminal tail, a loop containing residues 76-91, and a cis versus trans peptide linkage at residue Thr 322. The cis to trans peptide variation appears to be an interspecies difference between turkey and duck and is therefore not directly involved in the loss of enzymatic activity. All the residues implicated in the catalytic mechanism are conserved in both the active and inactive proteins, and given the linearity of the relationship between the enzymatic activity of duck delta I/delta II heterotetramers and their delta II content (Piatigorsky & Horwitz, 1996), it is evident from the structure that only one of the three domains that contributes to the active site is responsible for the loss of activity in the delta I protein. Given the structural differences found in domain 1 (N-terminal tail and 76-91 loop), we postulate that these differences are responsible for the loss of catalytic activity in the delta I crystallin protein and that the delta I protein is inactive because it no longer binds the substrate. PMID- 9369473 TI - Active site cavity of herpesvirus proteases revealed by the crystal structure of herpes simplex virus protease/inhibitor complex. AB - Human herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are responsible for herpes labialis (cold sores) and genital herpes, respectively. They encode a serine protease that is required for viral replication, and represent a viable target for therapeutic intervention. Here, we report the crystal structures of HSV-1 and HSV-2 proteases, the latter in the presence and absence of the covalently bound transition state analog inhibitor diisopropyl phosphate (DIP). The HSV-1 and HSV-2 protease structures show a fold that is neither like chymotrypsin nor like subtilisin, and has been seen only in the recently determined cytomegalovirus (CMV) and varicella-zoster virus (VZV) protease structures. HSV-1 and HSV-2 proteases share high sequence homology and have almost identical three-dimensional structures. However, structural differences are observed with the less homologous CMV protease, offering a structural basis for herpes virus protease ligand specificity. The bound inhibitor identifies the oxyanion hole of these enzymes and defines the active site cavity. PMID- 9369474 TI - High-resolution crystal structures of delta5-3-ketosteroid isomerase with and without a reaction intermediate analogue. AB - Bacterial Delta5-3-ketosteroid isomerase (KSI) catalyzes a stereospecific isomerization of steroid substrates at an extremely fast rate, overcoming a large disparity of pKa values between a catalytic residue and its target. The crystal structures of KSI from Pseudomonas putida and of the enzyme in complex with equilenin, an analogue of the reaction intermediate, have been determined at 1.9 and 2.5 A resolution, respectively. The structures reveal that the side chains of Tyr14 and Asp99 (a newly identified catalytic residue) form hydrogen bonds directly with the oxyanion of the bound inhibitor in a completely apolar milieu of the active site. No water molecule is found at the active site, and the access of bulk solvent is blocked by a layer of apolar residues. Asp99 is surrounded by six apolar residues, and consequently, its pKa appears to be elevated as high as 9.5 to be consistent with early studies. No interaction was found between the bound inhibitor and the residue 101 (phenylalanine in Pseudomonas testosteroni and methionine in P. putida KSI) which was suggested to contribute significantly to the rate enhancement based on mutational analysis. This observation excludes the residue 101 as a potential catalytic residue and requires that the rate enhancement should be explained solely by Tyr14 and Asp99. Kinetic analyses of Y14F and D99L mutant enzymes demonstrate that Tyr14 contributes much more significantly to the rate enhancement than Asp99. Previous studies and the structural analysis strongly suggest that the low-barrier hydrogen bond of Tyr14 (>7.1 kcal/mol), along with a moderate strength hydrogen bond of Asp99 ( approximately 4 kcal/mol), accounts for the required energy of 11 kcal/mol for the transition-state stabilization. PMID- 9369475 TI - Alanine scanning mutagenesis of the switch I region in the ATPase site of Dictyostelium discoideum myosin II. AB - In order to determine the functional roles of the conserved sequence (NXNSSRFG) of the "switch I" loop (residues 233-240 in Dictyostelium myosin II), alanine scanning mutagenesis was performed on Dictyostelium myosin II. N233A and S237A mutant myosins did not bind a fluorescent analog of ADP, mant-deoxyADP, at the low concentration range (micromolar and had low level of ATPase activities. They were nonmotile when examined by the in vitro motility assay. Dictyostelium cells expressing these myosins showed worse phenotypes than that of myosin-null cells. In contrast to these mutant myosins, R238A myosin tightly bound mant-deoxyADP. However, the mutant had a defect in the ATP hydrolysis step and exhibited the lowest ATPase activities among the mutants examined here. The R238A myosin was nonmotile. R238C or R238H mutations, which mimic the Usher syndrome mutations, generated myosins with similar functional defects to those of the R238A mutation. Cells expressing the R238A myosin exhibited the phenotype similar to that of the myosin-null cells. N235A, S236A, F239A, and G240A myosins retained moderate levels of ATPase activities and could drive sliding of actin filaments at various speeds. Phenotypes of cells expressing them were very similar to that of the wild type cells. Taken together, these results suggest that side chains of N233 and S237 may play essential roles in holding a nucleotide in the ATPase pocket and that R238 may play crucial roles in the ATP hydrolysis step, while those of the other residues in the switch I loop are not essential for the process. PMID- 9369476 TI - Cyanide and nitric oxide binding to reduced protocatechuate 3,4-dioxygenase: insight into the basis for order-dependent ligand binding by intradiol catecholic dioxygenases. AB - EPR-silent, chemically reduced protocatechuate 3,4-dioxygenase (Er) binds NO at the active site Fe2+ to yield an EPR-active, S = 3/2 species that blocks subsequent binding of all other exogenous ligands. In contrast, addition of NO to a preformed Er.CN- complex yields an EPR-active, S = 1/2 species [Er.(CN)x.NO] that exhibits resolved superhyperfine splitting from 13CN-, 15/14NO, and a protein-derived 14N. Simulations of the EPR spectra observed for the Er.(CN)x.NO complex formed with 12CN- and 13CN- (1:1) show that CN- binds in two iron ligand sites (x >/= 2). The two cyanides exhibit similar, but distinguishable, hyperfine coupling constants. This demonstrates unambiguously that at least three exogenous ligands (two cyanides and NO) can bind to the Fe2+ simultaneously and strongly suggests that at least one histidine ligand is retained in the complex. The Er.(CN)>/=2.NO complex readily exchanges both of the bound cyanides for the substrate analog, 2-hydroxyisonicotinic acid N-oxide (INO), to form a Er.INO.NO complex exhibiting the same S = 3/2 type EPR spectrum that is observed for this complex in the absence of CN-. Because the dead-end Er.NO complex does not accumulate during the exchange, the results suggest that Er.(CN)>/=2. NO and Er.INO.NO are in conformational states that allow facile exchange of INO and CN- but not NO. The results are interpreted in the context of the known X-ray crystal structures for the ferric form of the resting enzyme (Eox) and numerous Eox.substrate, inhibitor, and CN- complexes, all of which have a charge neutral iron center. It is proposed that the binding of one CN- causes dissociation of an anionic endogenous ligand which begins a series of conformational changes analogous to those initiated by anionic substrate binding to Eox. This results in a new unique coordination site for NO, and a new second site for CN-; both cyanide sites are utilized when the enzyme subsequently binds substrates or INO. PMID- 9369477 TI - RNA dependent DNA replication fidelity of HIV-1 reverse transcriptase: evidence of discrimination between DNA and RNA substrates. AB - The RNA dependent DNA replication fidelity of HIV-1 reverse transcriptase has been investigated using pre-steady-state kinetics under single turnover conditions. In contrast to previous estimates of low replication fidelity of HIV 1 reverse transcriptase, the present study finds the enzyme to be more highly discriminating when an RNA/DNA template-primer is employed as compared with the corresponding DNA/DNA template-primer. The basis of this selectivity is due to extremely slow polymerization kinetics for incorporation of an incorrect deoxynucleotide. The maximum rates for misincorporation (kpol) of dGTP, dCTP, and dTTP opposite a template uridine were 0.2, 0.03, and 0.003 s-1, respectively. The equilibrium dissociation constants (Kd) for the incorrect nucleotide opposite a template uridine were 1.0, 1.1, and 0.7 mM for dGTP, dCTP, and dTTP, respectively. These kinetic values provide fidelity estimates of 26 000 for discrimination against dGTP, 176 000 for dCTP, and 1 x 10(6) for dTTP misincorporation at this position. Similar observations were obtained when incorrect nucleotide misincorporation was examined opposite a template adenine. Thus in a direct comparison of RNA/DNA and DNA/DNA template-primer substrates, HIV-1 RT exhibits approximately a 10-60-fold increase in fidelity. This study augments our current understanding of the similarities and differences of catalytic activity of HIV-1 reverse transcriptase using RNA and DNA substrates. Moreover, these studies lend further support for a model for nucleotide incorporation by HIV-1 reverse transcriptase involving a two-step binding mechanism governed by a rate-limiting conformational change for correct incorporation. PMID- 9369478 TI - Pre-steady-state kinetic characterization of wild type and 3'-azido-3' deoxythymidine (AZT) resistant human immunodeficiency virus type 1 reverse transcriptase: implication of RNA directed DNA polymerization in the mechanism of AZT resistance. AB - There is lack of a correlation between biochemical studies and the observed clinical resistance of AIDS patients on long term AZT therapy. Mutant HIV-1 reverse transcriptase in the viral isolates from these patients shows a 100-fold decrease in sensitivity whereas little or no difference is observed in kinetic parameters in vitro using steady-state kinetic analysis. A detailed pre-steady state kinetic analysis of wild type and the clinically important AZT resistant mutant (D67N, K70R, T215Y, K219Q) HIV-1 reverse transcriptase was conducted to understand the mechanistic basis of drug resistance. In contrast to steady-state techniques, a pre-steady-state kinetic analysis allows for the direct observation of catalytic events occurring at the active site of the enzyme, including subtle conformational changes enabling a greater degree of mechanistic detail. In this investigation the rate of incorporation of dTMP and AZTMP by wild type and mutant HIV-1 RT was determined using an RNA and the corresponding DNA template. The present study has shown a 1.5-fold decrease in the rate constant for polymerization (kpol) and a 2.5-fold decrease in the equilibrium dissociation constant (Kd) for AZTTP for the mutant reverse transcriptase as compared to the wild type, for RNA dependent DNA replication. These values translate into a 4 fold decrease in selectivity (kpol/Kd) for AZTMP incorporation by mutant reverse transcriptase as compared to wild type for RNA dependent DNA replication. No such decrease in selectivity was detected for DNA dependent replication. These results suggest that the basis of AZT resistance is related to RNA dependent replication rather than DNA dependent replication. PMID- 9369479 TI - Inhibition of klenow fragment (exo-) catalyzed DNA polymerization by (5R)-5,6 dihydro-5-hydroxythymidine and structural analogue 5,6-dihydro-5-methylthymidine. AB - Oligonucleotides containing 5R-5,6-dihydro-5-hydroxythymidine (5R-3) and structural analogue 5,6-dihydro-5-methylthymidine (9) at defined sites were chemically synthesized via a method that obviates the use of NH4OH. Oligonucleotides prepared by this method were used to examine the effects of 5R-3 and 9 on the fidelity of Klenow (exo-) in vitro. The presence of lesions 5R-3 and 9 in DNA templates was shown to inhibit polymerization of primers hybridized to these templates. Inhibition was observed for both translesional synthesis and extension one nucleotide past the lesion, with the latter being more pronounced. The fidelity of Klenow (exo-) was reduced only slightly when utilizing substrates containing either dihyropyrimidine nucleotide. These results provide the first experimental verification of computational studies carried out on the effects of 3 on DNA templates, and are consistent with a structural model in which the C5 methyl group of 5R-3 adopts a pseudoaxial orientation resulting in a disruption in base stacking. PMID- 9369480 TI - A hexameric helicase encircles one DNA strand and excludes the other during DNA unwinding. AB - The bacteriophage T7 DNA helicase/primase (gene 4 protein) is a ring-like hexamer that encircles ssDNA and requires forked DNA to catalyze DNA unwinding. We report that optimal rates of unwinding of forked DNA require ssDNA tails of 55 nucleotides on the 5'-to-3' strand and 15 nucleotides on the 3'-to-5' strand. Surprisingly, streptavidin bound to a biotinylated 3'-end fully substitutes for the 3'-to-5' ssDNA tail. This suggests that excluding the 3'-to-5' DNA strand from the center of the helicase is an essential aspect of the mechanism of hexameric helicase-catalyzed DNA unwinding. We also report that streptavidin bound to a biotinylated dT within the 5'-to-3' strand of the duplexed region abolishes DNA unwinding; whereas, streptavidin bound to a biotinylated dT within the duplexed region of the other strand has no effect. These results unambiguously demonstrate that the T7 gene 4 protein is a 5'-to-3' helicase and imply that during DNA unwinding the 5'-to-3' strand transverses the center of the ring while the 3'-to-5' strand is excluded from the center of the ring. Implications for collisions between a helicase and other protein-DNA complexes are discussed. PMID- 9369481 TI - The orphan nuclear receptor TR2 suppresses a DR4 hormone response element of the mouse CRABP-I gene promoter. AB - The mouse orphan nuclear receptor TR2-11-f suppressed the expression of reporters fused to a hormone response element of the mouse cellular retinoic acid-binding protein I gene promoter. TR2-11-f was able to bind to a direct repeat with four nucleotides in the spacer (5'TGACCTTTGGGGACCT3') located within this hormone response element as homodimers. The specificity of protein-DNA interactions was demonstrated by competition in gel retardation and antibody-mediated supershift reactions. The residues critical for TR2-11-f binding were mapped to both repeated sequences, whereas the spacer and the flanking sequences were less important. The Kd and Bmax of TR2-11-f homodimer binding to this direct repeat were determined to be 2.6 nM and 0.012 nM, respectively. By using a yeast two hybrid system, it was demonstrated that dimerization of TR2-11-f was mediated by its ligand-binding domain. The actions of TR2-11-f in regulating cellular retinoic acid-binding protein I gene will likely influence retinoic action and availability within the cells. PMID- 9369482 TI - The role of HNF1alpha, HNF3gamma, and cyclic AMP in glucose-6-phosphatase gene activation. AB - The gene for glucose-6-phosphatase (G6Pase), the key enzyme in glucose homeostasis, is expressed in a tissue-specific manner in the liver and kidney. To understand the molecular mechanisms regulating liver-specific expression of the G6Pase gene, we characterized G6Pase promoter activity by transient expression assays. The G6Pase promoter is active in HepG2 hepatoma cells, but inactive in JEG3 choriocarcinoma or 3T3 cells. DNA elements essential for optimal and liver specific expression of the G6Pase gene were contained within nucleotides -234 to +3. Deletion analysis revealed that the G6Pase promoter contained three activation elements (AEs) at nucleotides -234 to -212 (AE-I), -146 to -125 (AE II), and -124 to -71 (AE-III). AE-I contains binding sites for hepatocyte nuclear factors (HNF) 1 and 4. Electromobility shift and cotransfection assays demonstrated that HNF1alpha, but not HNF4, bound to its cognate site and transactivated G6Pase gene expression. The G6Pase promoter contained five HNF3 motifs, 1 (-180/-174), 2 (-139/-133), 3 (-91/-85), 4 (-81/-75), and 5 (-72/-66), and all five sites bound HNF3gamma with high affinity. Transient expression and cotransfection assays showed that HNF3 site 1 is not required for basal promoter activity, but is essential for HNF3gamma-activated transcription from the G6Pase promoter. We further showed that HNF3 sites 3, 4, and 5 were essential for basal G6Pase promoter activity and transactivation by HNF3gamma. AE-II contains, in addition to a HNF3 motif, a cAMP-response element (CRE) and a C/EBP half-site. The G6Pase(-146/-116) DNA containing AE-II formed multiple protein-DNA complexes with HepG2 nuclear extracts, including HNF3gamma, CRE-binding protein (CREB), C/EBPalpha, and C/EBPbeta. We showed that AE-II mediated transcription activation of the G6Pase gene by cAMP. PMID- 9369483 TI - A calcium-metalloribozyme with autodecapping and pyrophosphatase activities. AB - A previously-isolated ribozyme with capping activity has self-decapping activity, here characterized alongside its additional, somewhat parallel, pyrophosphatase reaction. Decapping is 10-50 times slower than the pyrophosphatase activity, depending on pH. The RNA accelerates pyrophosphate release 170 000 times over a control composed of randomized pppRNA, and 5' capped RNA accelerates decapping 1000-fold over random capped RNA. Triphosphate-linked G(5')pppRNA also supports an unusual cap-exchange reaction, exchanging its cap with guanosine 5' tetraphosphate to form pentaphosphate-linked G(5')pppppRNA. GDP, a capping reactant for the RNA, appears to suppress both decapping and pyrophosphatase activities. Autodecapping and pyrophosphatase activities have in common an unusual divalent metal ion requirement for Ca2+ or less effectively Mn2+, and both are active over a broad pH range of 4.5-9. 0. These characteristics resemble the capping activity of the same RNA. Kinetic analysis reveals a well-defined Ca2+-RNA complex, and Mg2+ and Sr2+ act as competitive inhibitors of Ca2+. A strong Ca2+-binding site is suggested by a low KM of 40-60 microM at pH >/= 7.0. The role of Ca2+ in these reactions can be surmized from literature data on reactivity of nucleotide phosphates. Pyrophosphatase, capping, and decapping activities of isolate 6 RNA are apparently carried out by a single reaction center, whose rate of reaction with all nucleophiles sums to a constant total rate. This suggests a universal rate-limiting step. Versatile activation of alpha phosphate by this reaction center raises the possibility of combinatorial ribozymes. PMID- 9369484 TI - Ligand-induced movement of helix X in the lactose permease from Escherichia coli: a fluorescence quenching study. AB - Five single-Trp mutants were constructed by replacing Val315, Leu318, Val326, Leu329, or Val331 with Trp in transmembrane helix X of a functional lactose permease mutant devoid of Trp residues (Trp-less permease). Taking into account expression levels, each single-Trp permease except for Val331-->Trp exhibits significant activity. The intrinsic fluorescence emission of each single-Trp mutant does not change significantly after addition of beta-d-galactopyranosyl 1 thio-beta-d-galactopyranoside (TDG), indicating that ligand induces little change in the microenvironment of the Trp residues. However, fluorescence quenching studies with the brominated detergent 7,8-dibromododecyl beta,d-maltoside (BrDM) demonstrate that a Trp residue in place of Val315, Val326, or Val331 becomes less accessible to BrDM in the presence of TDG, while a Trp residue in place of Leu318 or Leu329 becomes more accessible. Acrylamide quenching studies with Leu318-->Trp and Val331-->Trp permeases or 2-(4-maleimidoanilino)naphthalene-6-sulfonic acid (MIANS)-labeled Thr320-->Cys and Glu325-->Cys permeases indicate that positions 318 and 325 also become more accessible to a hydrophobic environment in the presence of TDG, while positions 320 and 331 become less accessible. The findings are consistent with a recently proposed mechanism for energy coupling in lactose permease [Kaback, H. R. (1997) Proc. Natl. Acad. Sci. U.S.A. 94, 5539-5543] in which substrate binding causes a conformational change resulting in movement of Glu325 to a nonpolar environment with a dramatic increase in pKa. PMID- 9369485 TI - Mitomycin C-DNA adducts generated by DT-diaphorase. Revised mechanism of the enzymatic reductive activation of mitomycin C. AB - Mitomycin C (MC) was reductively activated by DT-diaphorase [DTD; NAD(P)H:quinone oxidoreductase] from rat liver carcinoma cells in the presence of Micrococcus lysodeicticus DNA at pH 5.8 and 7.4. The resulting alkylated MC-DNA complexes were digested to the nucleoside level and the covalent MC-nucleoside adducts were separated, identified, and quantitatively analyzed by HPLC. In analogous experiments, two other flavoreductases, NADH-cytochrome c reductase and NADPH cytochrome c reductase, as well as two chemical reductive activating agents Na2S2O4 and H2/PtO2 were employed as activators for the alkylation of DNA by MC. DTD as well as all the other activators generated the four known major guanine-N2 MC adducts at both pHs. In addition, at the lower pH, the guanine-N7-linked adducts of 2,7-diaminomitosene were detectable in the adduct patterns. At a given pH all the enzymatic and chemical reducing agents generated very similar adduct patterns which, however, differed dramatically at the acidic as compared to the neutral pH. Overall yield of MC adducts was 3-4-fold greater at pH 7.4 than at 5. 8 except in the case of DTD when it was 4-fold lower. Without exception, however, cross-link adduct yields were greater at the acidic pH (2-10-fold within the series). The ratio of adducts of bifunctional activation to those of monofunctional activation was 6-20-fold higher at the acidic as compared to the neutral pH. A comprehensive mechanism of the alkylation of DNA by activated MC was derived from the DNA adduct analysis which complements earlier model studies of the activation of MC. The mechanism consists of three competing activation pathways yielding three different DNA-reactive electrophiles 11, 12, and 17 which generate three unique sets of DNA adducts as endproducts. The relative amounts of these adducts are diagnostic of the relative rates of the competing pathways in vitro, and most likely, in vivo. Factors that influence the relative rates of individual pathways were identified. PMID- 9369486 TI - Structural features of the final intermediate in the biosynthesis of the lantibiotic nisin. Influence of the leader peptide. AB - The antimicrobial membrane-interacting polypeptide nisin is a prominent member of the lantibiotic family, the members of which contain thioether-bridged residues called lanthionines. To gain insight into the complex biosynthesis and the structure/function relationship of lantibiotics, the final intermediate in the biosynthesis of nisin A was studied by nuclear magnetic resonance spectroscopy. In aqueous solution the leader peptide part of this precursor adopts predominantly a random coil structure, as does the synthetic leader peptide itself. The spatial structure of the fully modified nisin part of the precursor is similar to that of nisin in water. The leader peptide part does not interact with the nisin part of the precursor molecule. Thus, these two parts of the precursor do not influence each other's conformation significantly. The conformation of the precursor was also studied while complexed to micelles of dodecylphosphocholine, mimicking the primary target of the antimicrobial activity of nisin, i.e. the cytoplasmic membrane. The location of the molecule relative to the micelles was investigated by using micelle-inserted spin-labeled 5 doxylstearic acid. It was observed that the N-terminal half of the nisin part of the precursor interacts in a different way with micelles than does the corresponding part of mature nisin, whereas no significant differences were found for the C-terminal half of the nisin part. In this model system the leader peptide is in contact with the micelles. It is concluded that the strongly reduced in vivo activity of the precursor molecule relative to that of nisin is not caused by a difference in the spatial structure of nisin and of the corresponding part of precursor nisin in water or by a shielding of the membrane interaction surface of the nisin part of the precursor by the leader peptide. Probably a different interaction of the N-terminal part of the nisin region with membranes contributes to the low activity by preventing productive insertion. The residues of the leader peptide part just next to the nisin part are likely to contribute most to the low activity of the precursor. PMID- 9369487 TI - Transport of long-chain native fatty acids across lipid bilayer membranes indicates that transbilayer flip-flop is rate limiting. AB - Evidence from a number of laboratories suggests that membrane proteins may meditate the transport of physiologic fatty acids (FA) across cell membranes. However, studies using lipid membranes indicate that FA are capable of spontaneous flip-flip, raising the possibility that rapid transport through the lipid phase obviates the need for a transport protein. Determining the rate limiting steps for transport of FA across lipid membranes, therefore, is central to understanding FA transport across cell membranes. The transport of long-chain FA across lipid membranes, from the aqueous compartment on one side of the lipid bilayer to the aqueous phase on the other side, has not been measured previously. In this study, we have used the fluorescent probe ADIFAB to monitor the time course of FA movement from the outer to the inner aqueous compartments and from the lipid membrane to the outer aqueous compartment of lipid vesicles. These two measurements, together with measurements of the lipid:aqueous partition coefficients, allowed the determination of the rate constants for binding (kon), flip-flop (kff), and dissociation (koff) for the transport of long-chain natural FA across lipid vesicles. These rates were determined using large unilamellar vesicles (LUV) of approximately 1000 A diameter, prepared by extrusion and giant unilamellar vesicles (GUV), prepared by detergent dialysis, that are >/=2000 A diameter. The results of these studies for vesicles composed of egg phosphatidylcholine (EPC) and cholesterol reveal kff values that range from 3 to 15 s-1 for LUV and from 0.1 to 1.0 s-1 for GUV, depending upon temperature and FA type. For these same vesicles, dissociation rate constants range from 4 to 40 s-1 for LUV and from 0.3 to 2.5 s-1 for GUV. In all instances, the rate constant for flip-flop is smaller than koff, and because the rate of binding is greater than the rate of transport, we conclude that flip-flop is the rate-limiting step for transport. These results demonstrate that (1) kff and koff are smaller for GUV than for LUV, (2) the rate constants increase with FA type according to oleate (18:1) < palmitate (16:0) < linoleate (18:2), and (3) the barrier for flip-flop has a significant enthalpic component. Comparison of the flip-flop rates determined for GUV with values estimated from previously reported metabolic rates for cardiac myocytes, raises the possibility that flip-flop across the lipid phase alone may not be able to support metabolic requirements. PMID- 9369488 TI - Structural and functional characterization of retinal calcium-dependent guanylate cyclase activator protein (CD-GCAP): identity with S100beta protein. AB - Calcium-dependent guanylate cyclase activator protein (CD-GCAP) is a low molecular-weight retinal calcium-binding protein which activates rod outer segment guanylate cyclase (ROS-GC) in a calcium-dependent manner. This investigation was undertaken to determine the protein's structure and identity. Partial amino acid sequencing (72% of the protein), mass spectral analysis, cloning, and immunological studies revealed that CD-GCAP is identical to S100beta, another low-molecular-weight calcium-binding protein whose structure was known. We had shown earlier that the latter protein, which is usually called S100b (S100betabeta or dimer of S100beta), also activates ROS-GC but that the Vmax of activated cyclase was about 50% lower than when stimulated by CD-GCAP. S100b also required about 15 times more calcium (3.2 x 10(-)5 vs 1.5 x 10(-)6 M) for half-maximal stimulation of cyclase. To investigate the possibility that CD GCAP is a post-translationally modified form of S100b, both proteins were treated with 1 M hydroxylamine which is known to deacylate proteins. After the treatment, CD-GCAP did not activate cyclase while S100b activation remained unaffected suggesting that CD-GCAP could not be a modified form of S100b. Hydroxylamine also broke down CD-GCAP into smaller fragments while leaving S100b intact. It therefore appeared that in spite of identical primary structures, the conformations of the two proteins were different. We then investigated the possibility that the purification procedures of the two proteins, which were quite different, could have contributed to such conformational differences: CD GCAP purification included a step of heating at 75 degrees C in 5 mM Ca, while S100b purification included zinc affinity chromatography. To test the influence of these treatments on the properties of the proteins, CD-GCAP was subjected to zinc affinity chromatography and purified as S100b (CD-GCAP-->S100b) and S100b was heated in Ca and purified as CD-GCAP (S100b-->CD-GCAP). Cyclase activation, calcium-sensitivity, and hydroxylamine-lability measurements revealed that CD GCAP-->S100b is identical to S100b and that S100b-->CD-GCAP is identical to CD GCAP. Taken together the results demonstrate that CD-GCAP and S100b are one and the same protein and that their functional differences are due to different interconvertible conformational states. PMID- 9369489 TI - Isolation and properties of photochemically active reaction center complexes from the green sulfur bacterium Prosthecochloris aestuarii. AB - A new and rapid procedure was developed for the isolation of the reaction center core (RCC)-complex from the green sulfur bacterium Prosthecochloris aestuarii. Reaction center preparations containing the Fenna Matthews Olson (FMO) protein were also obtained. The procedure involved incubation of broken cells with the detergents Triton X-100 and SB12, sucrose gradient centrifugation and hydroxyapatite chromatography. Three different pigment protein complexes were obtained: one containing (about) three FMO trimers per RCC, one with one FMO per RCC and one consisting of RCC only. The last one contained polypeptides with apparent molecular masses of 64 kDa (pscA) and 35 kDa (pscB, the FA/FB, FeS subunit), but no cytochrome. Bacteriochlorophyll a and the chlorophyll a isomer functioning as primary electron acceptor were present at a ratio of 4.8:1. The complexes were also characterized spectroscopically and in terms of photochemical activity, at room temperature as well as at cryogenic temperatures. Illumination caused oxidation of the primary donor P840, with the highest activity in the RCC complex (DeltaA840/A810 = 0.06). At room temperature in the RCC complex essentially all of the P840+ produced in a flash was re-reduced slowly in the dark (several seconds). At low temperatures (150-10 K) a triplet was formed in a fraction of the reaction centers, presumably by a reversal of the charge separation, whereas in others P840+ formed in the light was re-reduced in 40-50 ms. PMID- 9369490 TI - Presence of two rhodopsin intermediates responsible for transducin activation. AB - To identify how many rhodopsin intermediates interact with retinal G-protein transducin, the photobleaching process of chicken rhodopsin has been investigated in the presence or absence of transducin by means of time-resolved low temperature spectroscopy. Singular value decomposition (SVD) analysis of the spectral data showed that a new intermediate called meta Ib is present between formally identified metarhodopsin I (now referred to as meta Ia) and metarhodopsin II (meta II). Since the absorption maximum of meta Ib (460 nm) is similar to that of meta Ia (480 nm), but considerably different from that of meta II (380 nm), meta Ib should have a protonated retinylidene Schiff base as its chromophore. Whereas transducin showed no effect on the conversion process between lumirhodopsin (lumi) and meta Ia, it affected the process between meta Ia and meta Ib and that between meta Ib and meta II. These results suggest that at least two intermediates (meta Ib and meta II) interact with transducin. The addition of GTPgammaS had no effect on the meta Ib-transducin interaction, while it abolished the ability of transducin to interact with meta II. Thus, meta Ib only binds to transducin, while meta II catalyzes a GDP-GTP exchange in transducin. These results suggest that deprotonation of the Schiff base chromophore is not necessary for the binding to transducin, while changes in protein structure including Schiff base deprotonation are needed to induce the GDP-GTP exchange in transducin. PMID- 9369491 TI - Detection and characterization of the lignin peroxidase compound II-veratryl alcohol cation radical complex. AB - Lignin peroxidases (LiP) from the white-rot fungus Phanerochaete chrysosporium oxidize veratryl alcohol (VA) by two electrons to veratryl aldehyde, although the VA cation radical (VA.+) is an intermediate [Khindaria, A., et al. (1995) Biochemistry 34, 6020-6025]. It was speculated, on the basis of kinetic evidence, that VA*+ can form a catalytic complex with LiP compound II. We have used low temperature EPR to provide direct evidence for the formation of the complex. The EPR spectrum of VA*+ obtained at 4 K was explained by a model for coupling between the oxoferryl moiety of the heme (S = 1) and VA.+ (S = 1/2) similar to the model proposed for an oxyferryl and a porphyrin pi cation radical of horseradish peroxidase. The coupling constant suggested that VA.+ was equally ferro- and antiferromagnetically coupled to the oxoferryl moiety. The spectrum was simulated with g perpendicular only marginally greater than g parallel. This was surprising since the only other known organic radical coupled to the heme iron in a peroxidase is the tryptophan cation radical in cytochrome c peroxidase which exhibits a g tensor with g parallel greater than g perpendicular. Spin concentration analysis suggested that the 1 mol of VA*+ was coupled to the oxoferryl moiety per mole of enzyme. The VA.+ signal decayed with a first-order decay constant of 1.76 s-1, in close agreement with the earlier published decay constant of 1.85 s-1 from room-temperature EPR studies. The exchange coupling between VA.+ and the oxoferryl moiety strongly advocates calling this species (VA.+ and LiP compound II) a catalytic complex. PMID- 9369492 TI - Crystal structure of the complex of bovine pancreatic phospholipase A2 with the inhibitor 1-hexadecyl-3-(trifluoroethyl)-sn-glycero-2-phosphomethanol,. AB - The structure of recombinant bovine pancreatic phospholipase A2 (PLA2) complexed with the competitive inhibitor 1-hexadecyl-3-(trifluoroethyl)-sn-glycero -2 phosphomethanol (hereafter MJ33), a phospholipid analogue without the sn-3 phosphodiester group, has been determined. The crystals are trigonal, space group P3121, a = b = 46.36 A and c = 102.56 A, and isomorphous to the recombinant PLA2 with one molecule in the asymmetric unit. The structure was refined using 8082 reflections between 8.0 and 1.91 A resolution to a final R-value of 18.4% [Rfree = 28.0%]. The model includes 957 protein atoms, 86 water molecules, one calcium ion, and 26 non-hydrogen atoms of the inhibitor MJ33. The overall tertiary fold of the complex is very similar to that of the inhibitor-free recombinant PLA2 with a root mean square deviation of 0.32 A for all the backbone atoms. The electron density of the surface loop residues 62-66 is clear and ordered, unlike the other trigonal bovine PLA2 structures done to date. This structural change could be responsible for the interfacial allosteric activation, which thermodynamically relates the enhanced binding of the substrate mimic to the active site of the enzyme. MJ33 is tightly bound in the active-site cleft, dislodging the equatorial coordinated calcium water (W5), the putative catalytic water W6, and the neighboring water W7. The axial coordinated calcium water is missing; thus the hexacoordinated calcium is a monocapped pentagonal pyramid. Although MJ33 is a sn-2 tetrahedral mimic, its phosphate binds to PLA2 differently from the sn-2 phosphonate analogue of phospholipids, another tetrahedral mimic. The knowledge of the active-site geometry of MJ33 would be useful in the design of more useful therapeutic agents for PLA2. PMID- 9369493 TI - 19F NMR study on the regiospecificity of hydroxylation of tetrafluoro-4 hydroxybenzoate by wild-type and Y385F p-hydroxybenzoate hydroxylase: evidence for a consecutive oxygenolytic dehalogenation mechanism. AB - The regiospecificity of hydroxylation of tetrafluoro-4-hydroxybenzoate (F4-POHB) by p-hydroxybenzoate hydroxylase (PHBH) and its active site mutant Y385F was investigated by 19F NMR. Evidence is provided that the hydroxylation of F4-POHB is not restricted to the C3 center of the aromatic ring but rather involves sequential oxygenation and dehalogenation steps. The catalytic efficiency of PHBH and Y385F with F4-POHB was optimal near pH 6.5. Below pH 7.0, substantial substrate inhibition occurred. Dianionic F4-POHB was a competent effector, highly stimulating upon binding the rate of flavin reduction by NADPH. Hydroxylation of F4-POHB involved the formation of quinone intermediates as primary products of oxygenolytic defluorination. Ascorbate competed favorably with NADPH for the nonenzymatic reduction of these reactive intermediates and prevented the accumulation of nonspecific oxidation products. 19F NMR showed that the initial aromatic product 2,5,6-trifluoro-3,4-dihydroxybenzoate (F3-DOHB) was further converted to 5,6-difluoro-2,3,4-trihydroxybenzoate (5,6-F2-TOHB). This reaction was most efficient with Y385F. F3-DOHB was not bound in a unique regiospecific orientation as also 2,6-difluoro-3,4, 5-trihydroxybenzoate (2,6-F2-TOHB) was formed. The oxygenolytic dehalogenation of F3-DOHB by PHBH and Y385F is consistent with the electrophilic aromatic substitution mechanism proposed for this class of flavoenzymes. Nucleophilic attack of the carbon centers of F3-DOHB onto the distal oxygen of the electrophilic flavin C(4a)-hydroperoxide occurs when the carbon center has a relatively high HOMO density and is relatively close to the distal oxygen of the flavin C(4a)-hydroperoxide. PMID- 9369494 TI - Conformation of the trypanocidal pharmaceutical suramin in its free and bound forms: transferred nuclear overhauser studies. AB - Suramin is a lead compound for treatment of cancer, HIV, and trypanosomiasis. The conformations of suramin in its free form and bound to phosphoglycerate kinases from T. brucei and S. cerevisae, have been studied in aqueous solutions using nuclear Overhauser effect (NOE) and transferred NOE NMR spectroscopies. The NOE data of the free drug can be accommodated by a model in which many of the single bonds of suramin are unrestricted at room temperature, consistent with molecular mechanics calculations. The angle between the naphthalene ring and the adjoining amide is essentially locked by a strong amide-sulfonate hydrogen bond into one preferred conformation. Another degree of freedom near the termini of the molecule has a rather pronounced preference, and a third exhibits a nearly perpendicular arrangement between the amide and adjacent aromatic ring. The other two degrees of freedom have weaker preferences. Molecular mechanics calculations using AMBER force field and charges on amides and sulfonates obtained from semiempirical or ab initio calculations reproduced the extent of nonplanarity but not the detailed preferences. 13C spin-lattice relaxation, proton NOE, and light scattering measurements for free suramin indicate that the correlation time of the molecule is approximately 3 ns at 5 mM concentration, suggesting that suramin is multimeric. Lowering the temperature to 5 degrees C causes a dramatic broadening of all of the resonances in the NMR spectra of 5 mM suramin. This broadening probably is associated with further aggregation into micelles. Suramin is monomeric at 0.5 mM and room temperature, and the NOE cross-relaxation rate constants are close to the cancellation condition for a 500 MHz proton frequency; this concentration is typical of blood serum concentrations when the drug is utilized in humans. Changes in the conformational preferences for terminal degrees of freedom are observed in the bound states of suramin based upon the transferred NOE data. The data for the bound state cannot be accommodated by a symmetric conformer. Analysis of the transferred NOESY buildup curves indicates complex kinetics of binding, probably involving an electrostatically bound encounter complex. Despite the weak binding constant, the buildup curves cannot be treated as population-weighted averages of the free and bound cross-relaxation rates, and therefore complete relaxation-exchange matrix analysis has been performed to simulate the data sets. PMID- 9369495 TI - Characterization of phosphine complexes of technetium(III) as transport substrates of the multidrug resistance P-glycoprotein and functional markers of P glycoprotein at the blood-brain barrier. AB - The multidrug resistance (MDR1) P-glycoprotein functions as a broad specificity efflux transporter of structurally diverse natural product and xenobiotic compounds. P-glycoprotein also is an important component of the functional blood brain barrier. To enable further studies of function and modulation of MDR1 P glycoprotein in vitro and in vivo, two novel phosphine technetium(III) complexes were designed and characterized: trans-[2,2'-(1, 2-ethanediyldiimino)bis(1, 5 methoxy-5-methyl-4-oxo-hexenyl)]bis[methylbis(3-methoxy-1- propyl)ph osphine]Tc(III) (Tc-Q58) and trans-[5,5'-(1,2-ethanediyl diimino)bis(2-ethoxy-2 methyl-3-oxo-4-pentenyl)]bis[dimethyl(3- methox y-1-propyl)phosphine)]Tc(III) (Tc Q63). In human drug-sensitive KB 3-1 cells and multidrug-resistant KB 8-5 and 8-5 11 derivative cell lines, expressing nonimmunodetectable, low, and high levels of MDR1 P-glycoprotein, respectively, accumulation of Tc-Q58 and Tc-Q63 was inverse to expression of the transporter. Differences between drug-sensitive and multidrug-resistant cells, while detectable at picomolar concentrations of each radiopharmaceutical, were independent of tracer concentration. Ratios of tracer accumulation in KB 3-1 and 8-5 cells were 62.3 and 48.1 for Tc-Q58 and Tc-Q63, respectively. Cell contents of Tc-Q58 and Tc-Q63 were enhanced up to 60-fold in MDR cells by known modulators of MDR1 P-glycoprotein, while drugs not in the multidrug-resistant phenotype had no effect on their accumulation. In KB 8-5 cells, potency of modulators was GF120918 >> cyclosporin A > verapamil. Accumulation of Tc-Q58 and Tc-Q63 in Sf9 insect cells infected with a recombinant baculovirus containing human MDR1 P-glycoprotein was reduced in a GF120918 reversible manner (EC50 = 70 nM) compared with cells infected with a wild-type baculovirus. By contrast, cell contents of Tc-Q58 or Tc-Q63 in Sf9 cells expressing the homologous MDR3 P-glycoprotein did not differ from wild-type virus. Demonstrating molecular targeting of these complexes in vivo, distribution and retention of Tc-Q58 in brain tissue of FVB mice treated with a saturating dose of GF120918 and mice deficient in the mdr1a gene [mdr1a (-/-)] were enhanced 180% and 520% over control, respectively. Exploiting the gamma-emission spectrum of 99mTc, increased uptake of Tc-Q58 in brain tissue of mdr1a (-/-) mice was readily detected noninvasively by scintigraphic imaging. Thus, both Tc-Q58 and Tc Q63 are demonstrated to be substrates for transport by MDR1 P-glycoprotein, broadening the specificity of this transporter to include phosphine-containing metal complexes. As shown with Tc-Q58, these Q complexes can be used to detect transport activity and modulation of MDR1 P-glycoprotein in vitro and to directly monitor the functional status of P-glycoprotein at the blood-brain barrier in vivo. PMID- 9369496 TI - ATP-ADP exchange reaction catalyzed by Na+,K+-ATPase: dephosphorylation by ADP of the E1P enzyme form. AB - We studied the effects of Mg2+ and of ADP and other nucleoside diphosphates on the dephosphorylation of the E1P form of the partially purified pig kidney Na+,K+ ATPase at 20-22 degrees C. We report for the first time the rate of the reversal of ATP phosphorylation. The experiments were done on enzyme subjected to controlled chymotrypsin digestion consisting of a homogenous population of a truncated catalytic subunit. Under this condition the whole cycle is E1 <-- (f1.ATP, b1) --> E1ATP <-- (f2, b2) --> E1P.ADP <-- (fd, bd.ADP) --> E1P-(f3) --> E1. The values of f1, b1, f2, and f3 were independently estimated in the absence of ADP; those of fd, bd, and b2 were obtained from the fit of ADP-dependent dephosphorylation data to the differential equation set. When f2 = 0 or b1 is very large, the model predicts that dephosphorylation by ADP gives a single exponential; in all other cases it predicts a biphasic dephosphorylation in a semilogarithmic plot. The fast phase is governed by b2.ADP and the slow one by b1. This was experimentally verified. Also, ADP stimulates E1P breakdown without release of Pi, thus leading to ATP synthesis. The data indicate that the true substrate for ATP synthesis is free ADP, while Mg2+ inhibits mainly by a reduction in the free [ADP]; in addition, E1P has a very low affinity for MgADP. The nucleotide structure is also very important; all ADP analogues tested were much less effective than ADP due to a reduced affinity for the E1P and a poor capacity to reverse phosphorylation. PMID- 9369497 TI - Proton and electron transfer to the secondary quinone (QB) in bacterial reaction centers: the effect of changing the electrostatics in the vicinity of QB by interchanging asp and glu at the L212 and L213 sites. AB - The bacterial reaction center (RC) plays a central role in photosynthetic energy conversion by facilitating the light induced double reduction and protonation of a bound quinone molecule, QB. Two carboxylic acid residues, Asp-L213 and Glu L212, located near QB, were previously shown to be important for proton transfer to QB. In this work, the ability of Glu to substitute for Asp at L213 and Asp to substitute for Glu at L212 was tested by site-directed mutagenesis. Both single mutants and a double mutant in which Asp and Glu were exchanged between the two sites were constructed. The electron transfer rate constants kBD (D+QAQB- --> DQAQB), and kAB(2) (DQA-QB- + H+ --> DQA(QBH)-), that are known to be sensitive to the energy of the QB- state, were found to be altered by Asp/Glu substitutions. Both rates were fastest ( approximately 10-fold) in RCs with Asp at both sites, slowest with Glu at both sites ( approximately 50-fold) and relatively unchanged by the caboxylic acid exchange. These changes could be explained if Asp was predominantly ionized and Glu was predominantly protonated at both sites (pH 7.5). The charge recombination kBD suggests an observed approximately 5 pKa unit difference of Glu over Asp. Modeling of kBD by strong electrostatic interactions ( approximately 3-4 pKa units) among negatively charged acids and QB- indicated a lower intrinsic pKa for Asp compared to Glu at either site of approximately 2-3 units. The mechanism of the kAB(2) reaction was determined to be the same in all mutant RCs as for native RCs. A quantitative explanation of the effect of the electrostatic environment on kAB(2) was obtained using the two-step model proposed for native RCs [Graige, M. S., Paddock, M. L., Bruce, J. M., Feher, G., & Okamura, M. Y. (1996) J. Am. Chem. Soc. 118, 9005 9016] which involves fast protonation of the semiquinone followed by rate limiting electron transfer. Using simple models for the quinone/quinol conversion rate, it is shown that the optimal electrostatic potential for the QB site is close to that found in native RCs. PMID- 9369498 TI - Human recombinant phosphodiesterase 4B2B binds (R)-rolipram at a single site with two affinities. AB - The interactions between (R)-rolipram and purified human recombinant low-Km, cAMP specific phosphodiesterase (HSPDE4B2B) constructs were investigated using biochemical, kinetic, and biophysical approaches. The full-length protein (amino acids 1-564) and an N-terminal truncated protein (amino acids 81-564) exhibited high-affinity (R)-rolipram binding, whereas an N-terminal and C-terminal truncated protein (amino acids 152-528) lacked high-affinity (R)-rolipram binding. The 152-528 and 81-564 proteins had similar Km's and kcat/Km's and differed less than 4-fold compared with the 1-564 protein. (R)-Rolipram inhibition plots were biphasic for the 1-564 and 81-564 proteins and fit to two states, a high-affinity (Ki = 5-10 nM) state and a low-affinity (Ki = 200-400 nM) state, whereas the 152-528 protein fit to a single state (Ki = 350-400 nM). The stoichiometry for high-affinity binding using a filter binding assay was found to be <1 mol of (R)-rolipram per mole of 1-564 or 81-564 protein. Titration microcalorimetric studies revealed both a high-affinity state with a stoichiometry of 0.3 mol of (R)-rolipram per mole of protein and a low-affinity state with a stoichiometry of 0.6 mol of (R)-rolipram per mole of protein for the 81-564 protein. A single low-affinity state with a stoichiometry of 0.9 mol of (R)-rolipram per mole of protein was seen using the 152-528 protein. The data indicate that purified HSPDE4B2B 1-564 and 81-564 proteins contain a single binding site for (R)-rolipram and suggest that the proteins exist in two different states distinguishable by their affinity for (R)-rolipram. Furthermore, the high-affinity binding state of the protein requires amino acid residues at the N-terminus (81-151) of the protein and catalytic domain (152-528), whereas the low-affinity binding state only requires residues in the catalytic domain (152-528). Phosphorylation at residues 487 and 489 of the 81-564 protein does not appear to alter the substrate kinetics or the stoichiometry and binding affinity of (R)-rolipram. PMID- 9369499 TI - Evidence that nonbilayer phase propensity of the membrane is important for the side chain cleavage activity of cytochrome P450SCC. AB - To analyze whether specific protein-lipid interactions or physical features of the membrane contribute to cytochrome P450SCC (CYP11A1) activation by lipids, dimyristoylphosphatidylcholine/cardiolipin and dimyristoylphosphatidylcholine/branched phosphatidylcholine vesicles of defined acyl chain structure were studied for their ability to stimulate the side chain cleavage activity of the enzyme. Activation was found to increase with the mole percent of nonbilayer lipids in the system and the chain lengths of both the branched and main fatty acyl chains of the activator lipid. Unsaturation provided by dioleoylphosphatidylcholine as host lipid leads to a further increase in the potency of the branched phosphatidylcholines to activate the enzyme. The observed activation can be qualitatively interpreted in terms of the effect of these lipids on the hydrophobic volume of the membrane. Using differential scanning calorimetry, we showed that the branched phosphatidylcholines perturb the bilayer membrane structure of dimyristoylphosphatidylcholine and lower the bilayer to hexagonal phase transition temperature of dielaidoylphosphatidylethanolamine, i.e., promote hexagonal phase formation. We also examined the effect of eicosane on both the cytochrome P450SCC activity and the lipid polymorphism and found that eicosane increases both the activity and the hexagonal phase propensity of the vesicle membrane. Because of these correlations, we conclude that the nonbilayer phase propensity of the membrane rather than specific binding of activator lipids to the enzyme explains best the observed activation of enzymatic activity by the lipids. PMID- 9369500 TI - Determinants of organ tropism of Sendai virus. AB - Wild-type Sendai virus is exclusively pneumotropic in mice. Protease activation mutants, ts-f1 and F1-R, were isolated from persistently infected tissue culture cells. Additional mutants were isolated from wild-type Sendai virus with phenotypes similar to the pantropic mutant, F1-R. The genome of the mutants was sequenced and mutations were revealed in several proteins encoded by the genes. Three of the six mutations in the fusion (F) proteins were considered prime candidates for the determinant of pantropism. Characterization of the mutants led to the finding that the exchange (Ser to Pro) residue 115 next to the cleavage site of the F protein was the primary determinant that resulted in the enhanced cleavability of the F protein. Another important finding was bipolar budding of F1-R in polarized epithelial cells and mouse bronchial epithelium. This has been attributed to two mutations in the matrix (M) protein, at residues 128 (Asp to Gly) and 210 (Ile to Thr). Thus, the determinants of pantropism of F1-R are protease activation of the F protein and biopolar budding attributed to the mutated M protein. PMID- 9369501 TI - Non-accidental injury: a review of the radiology. AB - There have been many descriptions of the radiological features of non-accidental injury since John Caffey introduced the concept of inflicted injury and initially described some of the patterns of injury. Since then, our understanding of the radiologically detectable injuries has increased. This article provides a review of our current understanding of the lesions. PMID- 9369502 TI - Developmental intrahepatic shunts of childhood: radiological features and management. AB - The purpose of this study was to evaluate the role of radiological techniques in the diagnosis and management of developmental intrahepatic shunts. Hepatic vascular fistulae are recognised sequelae of liver trauma and intrahepatic tumours. However, there are rare developmental malformations which may present in childhood or later life and which may carry life-threatening complications. Retrospective analysis of clinical and radiological data was carried out in 24 patients. Anomalies evaluated were: (a) direct communication between hepatic artery and hepatic veins; (b) congenital hepatoportal arteriovenous malformations; and (c) congenital portocaval anastomosis with persistent flow through the ductus venosus. Although rare, the prompt recognition of these vascular anomalies allows early surgical or radiological intervention and reversal of the haemodynamic complications. PMID- 9369503 TI - Venous thrombosis in and after extracorporeal membrane oxygenation: detection and follow-up by color Doppler sonography. AB - The purpose of our study was to evaluate thrombosis of venous vessels during and after extracorporeal membrane oxygenation (ECMO) using color Doppler sonography. We prospectively performed serial color Doppler sonography investigations in 30 ECMO patients [age: newborn to 3 years, male:female = 20:10, venoarterial (VA) ECMO = 18, venovenous (VV) ECMO = 12]. During ECMO obstruction and/or thrombosis of the superior vena cava (SVC) was observed in 2 neonates on VA ECMO. Furthermore, a thrombotic clot from an initially open duct of Arantii with partial portal vein thrombosis, reaching into the inferior vena cava (IVC), occurred despite adequate heparinization. After ECMO, late septic SVC thrombus occurred in one neonate. IVC thrombus was observed in two pediatric VV ECMO patients. The overall incidence of venous clots was 20 % (6 of 30). Routine color Doppler sonography monitoring of vessels in children on and after ECMO was found to be useful for early detection of venous thrombosis. It enabled consequent administration of appropriate therapy as well as follow-up after decannulation and reconstruction. PMID- 9369504 TI - MRI of the gastrointestinal tract. AB - This article reviews the application of magnetic resonance imaging (MRI) to study the gastrointestinal (GI) tract. A summary of the current MRI techniques is included, emphasizing the choice of pulsing sequences, imaging plane, surface coils and intravenous and oral contrast agents for each of the different segments of the GI tract. The multiple available oral contrast agents are reviewed, including the role of both positive and negative. Finally, the major clinical applications of MRI in the GI tract are discussed by major disease categories (congenital abnormalities, inflammatory disease and benign and malignant neoplasms). The latter is further subdivided by GI tract segments such as esophagus, stomach, small bowel and colon. PMID- 9369505 TI - US and CT findings of small bowel neoplasms. AB - Small bowel (SB) neoplasms are very rare tumours, but are still associated with high mortality rates, since the tumour-related symptoms occur late and are non specific. In addition, endoscopy is not feasible in most cases, and radiological contrast studies do not reach the high accuracy obtained in the evaluation of upper and lower gastrointestinal tract. Cross-sectional imaging, and particularly CT, is becoming increasingly relevant in the diagnosis of these tumours. Both US and CT allow tumour detection, even when performed on an emergency basis, and are capable of showing the lesion as well as possible complications. Moreover, CT offers the possibility of a preoperative staging by evaluating tumour extension through the bowel wall, lymph node involvement and possible metastases. Finally, in most cases a direct correlation between cross-sectional findings and histology can be found, thus permitting tumour characterisation. PMID- 9369506 TI - Differentiation of hepatocellular adenoma and focal nodular hyperplasia of the liver: comparison of power Doppler imaging and conventional color Doppler sonography. AB - The aim of our study was to compare the diagnostic efficacy of power Doppler imaging and conventional color Doppler sonography for differentiating between hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH) of the liver. Thirty-one focal liver lesions (in 29 patients) with histologic proof of HCA (n = 9) or FNH (n = 22) were studied with power and color Doppler sonography according to a standardized examination protocol. The size of the lesions ranged between 1.5 and 14.5 cm (HCA, 3.5-14.5 cm, mean +/- SD 7.3 +/- 3.3 cm; FNH, 1.5-9.1 cm, mean +/- SD 5.1 +/- 2.1 cm). Intratumoral vessels with a venous Doppler spectrum, associated with either pulsatile or continuous peripheral flow, were detected in HCA (eight of nine lesions by power Doppler imaging and six of nine by color Doppler imaging) but not in FNH. In contrast, color signals with an arterial Doppler spectrum, radiating from the center to the periphery of the lesion, were depicted in FNH (20 of 22 cases by power Doppler imaging and 15 of 22 by color Doppler sonography) but not in HCA. Differentiation of HCA and FNH was achieved in 28 of 31 cases (90 %) by power Doppler imaging and in 21 of 31 (68 %) by color Doppler sonography (p < 0.01). Power Doppler imaging is superior to conventional color Doppler sonography in the depiction of the intratumoral flow characteristics of HCA and FNH, and enables a more accurate differential diagnosis than color Doppler sonography. PMID- 9369507 TI - CT in the diagnosis of abdominal wall hernias: a preliminary study. AB - The aim of the study was to estimate the value of CT in the diagnosis of abdominal wall hernias and at the same time to create a standard for this CT investigation. Twenty-four patients with suspected hernia of the abdominal wall were examined. All were operated on. The CT scans were assessed by two radiologists to estimate the interobserver variation. The CT diagnoses made by the two radiologists were correct in 83 % and 79 % of cases, respectively. The sensitivity was 0.83 in both CT evaluations and the specificity was 0.83 and 0.67, respectively. The predictive value of a positive CT finding was 0.94 and 0.88, while the predictive value of a negative CT finding was 0.63 and 0.57, respectively. The interobserver variation (kappa) was 0.87. The study therefore indicates that a positive CT finding of abdominal wall hernia is reliable, while a negative finding does not exclude the diagnosis. The interobserver variation of the CT diagnoses is acceptable. To achieve the highest diagnostic accuracy, it is recommended to always use the Valsalva manoeuvre, oral intake of contrast and 10/10 mm CT slices. PMID- 9369508 TI - Intestinal disease in acquired immunodeficiency: evaluation by CT. AB - Intestinal symptoms affect most AIDS patients at some point in their disease. The purpose of this study was to evaluate the use of CT in this setting. A total of 339 abdominal CT exams were reviewed for signs of intestinal disease. Abdominal CT scans of 45 patients with intestinal symptoms were compared with colonoscopy and histologic data. The CT results were correlated with CD4( +) T-lymphocyte counts and patient survival. More than 14 % of all abdominal CT exams displayed signs of enteric disease. Of the 45 patients studied with both CT and colonoscopy, 35 (78 %) had signs of intestinal disease by CT. Of these 35 patients, colonoscopic signs of an intestinal lesion were found in 29 and histologic proof of disease was established in 30 cases. Colonoscopy and histology detected 8 lesions missed by CT. There were 14 cases of unspecific colitis, 15 cases of cytomegalovirus (CMV) colitis, and 4 cases of enteric tuberculosis as per biopsy. Five patients presented with Kaposi's sarcoma and 1 with a non-Hodgkin's lymphoma. Neither colonoscopic nor CT signs of intestinal disease did reliably distinguish between histologic subgroups. Specifically, CMV colitis could not be distinguished from unspecific colitis. CD4( +) T-lymphocyte counts for histologic subgroups were not significantly different, either. No colonoscopic or histologic feature predicted survival, whereas low CD4 counts and ascites on CT indicated a poor prognosis. Whereas CT detects signs of intestinal disease in most AIDS patients, these signs remain largely unspecific. Colonoscopy and biopsies provide no consistently valid standard with which to compare CT because of controversial sensitivity and specificity of these methods. The CT technique detects small bowel as well as extraintestinal disease. Therefore, CT is an important diagnostic modality in abdominal disease of immunocompromised patients. PMID- 9369509 TI - MRI of plantar fasciitis. AB - At present, MRI is the only imaging method that can precisely visualize lesions of the superficial plantar aponeurosis, whether they be musculoaponeurositides, enthesopathies or tears, and whether they be acute or chronic, with or without complications. By its direct visualization of the lesion, MRI enables an accurate assessment of the injury to be made and thereby better orients the therapeutic strategy. PMID- 9369510 TI - Accuracy of single-energy quantitative computed tomography in the assessment of bone mineral density of cervical vertebrae. AB - Earlier studies have shown that single-energy quantitative computed tomography (SEQCT) is a reliable method for bone mineral density (BMD) measurements in thoracic and lumbar vertebrae. Moreover, SEQCT has proved to be a useful parameter in the selection of appropriate implants in cervical spondylodesis. The aim of this study was to determine the accuracy of SEQCT in cervical vertebrae BMD measurement. BMD with reference to calcium hydroxyapatite (Ca10[PO4]6[OH]2) was assessed by SEQCT in 100 human vertebral bodies of the cervical spine. Bone cylinders were then cut from the appropriate region of interest. The cylinder volume was determined by the liquid displacement technique. The density of the mineral component was measured following incineration at 1100 degrees C for 24 h. The calculated BMD was correlated with the SEQCT values, resulting in a coefficient of r = 0.79 (P < 0.01). Mean SEQCT values were significantly lower than those determined by direct density assessment (t-test for coupled sampling, P < 0.02). This result was in agreement with studies on thoracic and lumbar vertebrae. These data suggest that SEQCT can reliably measure BMD in the cervical spine. PMID- 9369511 TI - Diagnostic value of MR arthrography in detection of intrinsic carpal ligament lesions: use of cine-MR arthrography as a new approach. AB - Twenty-five patients with chronic wrist pain and a preliminary diagnosis of carpal instability were examined with conventional MR imaging and MR arthrography with single compartment intra-articular injection. A new cine-MR arthrography technique, with image acquisition at every 5 s during intra-articular injection, was performed in 17 subjects. The purpose of this study was to determine the diagnostic value of MR arthrography in ligamentous lesions of the wrist and to assess the value of cine-MR arthrography in comparison with arthroscopy and/or surgery. Magnetic resonance arthrography, a semi-invasive technique, increased the diagnostic accuracy of intrinsic carpal ligament injuries. Cine-MR arthrography can be considered as a promising technique especially for the evaluation of lunatotriquetral and scapholunate ligament injuries of the wrist. PMID- 9369512 TI - Scintigraphically negative skip metastasis in osteosarcoma. AB - The accurate pre-operative evaluation of the intramedullary extent of osteosarcoma is essential, as it determines the level of bone resection. Radiographs, isotope bone and MR imaging scans have been considered as reliable in detecting skeletal metastasis and skip lesions. We report a case of osteosarcoma of the distal femur with a large skip lesion proximally which was not visualized by either routine radiography or bone scintigraphy, and was not included within the scan field on the initial MR imaging scan. The implications on patient management and possible reasons for failure of imaging to reveal the skip metastasis are discussed. PMID- 9369513 TI - Intraosseous pneumatocyst of the ilium: CT findings in two cases and literature review. AB - Intraosseous pneumatocyst of the ilium is a rare lesion of uncertain origin. It predilects male subjects and may be associated or not with sacroiliac joint degenerative disease, intra-articular gas, sacral pneumatocyst, and communication with the articular space. To our knowledge, only 16 observations have been reported in the literature. We have evaluated with plain radiographs and CT two additional cases. Plain films frequently identify these lesions, but CT is the method of choice in demonstrating their air density and assessing the possible abnormalities of the surrounding bone and sacroiliac joints. PMID- 9369514 TI - Calcium pyrophosphate dihydrate crystal deposition disease presenting as a pseudotumor of the temporomandibular joint. AB - We report a case of a 66-year-old white woman with calcium pyrophosphate dihydrate (CPPD) crystal deposition disease. The patient related a 2-month history of swelling with tenderness over the left pre-auricular region. A CT scan suggested a synovial chondromatosis. Surgical removal was done and histologic study showed CPPD crystals. This disease rarely involves the temporomandibular joint (TMJ) and is not usually considered in the differential diagnosis. To our knowledge, only 14 cases have been reported in the literature. PMID- 9369515 TI - Radiology in the management of pleural disease. AB - This is a review of the role of radiological intervention in the pleural space. It discusses the radiological management of effusions, empyemas (including the use of fibrinolytic agents), pneumothoraces and pleural thickening. PMID- 9369516 TI - Automatic detection of ground glass opacities on lung HRCT using multiple neural networks. AB - The purpose of this study was to implement neural networks and expert rules for the automatic detection of ground glass opacities (GG) on high-resolution computed tomography (HRCT). Different approaches using self-organizing neural nets as well as classifications of lung HRCT with and without the use of explicit textural parameters have been applied in preliminary studies. In the present study a hybrid network of three single nets and an expert rule was applied for the detection of GG on 120 HRCT scans from 20 patients suffering from different lung diseases. Single nets alone were not capable to reliably detect or exclude GG since the false-positive rate was greater than 100 % with regard to the area truly involved, more than 50 pixels throughout, and the true-positive rate was greater than 95 %. The hybrid network correctly classified 91 of 120 scans. Mild GG was false positive in 15 cases with less than 50 pixels, which was judged not clinically relevant. The pitfalls were: partial volume effects of bronchovascular bundles and the chest wall. Motion artefacts and diaphragm were responsible for 11 misclassifications. Hybrid networks represent a promising tool for an automatic pathology-detecting system. They are ready to use as a diagnostic assistant for detection, quantification and follow-up of ground glass opacities, and further applications are underway. PMID- 9369517 TI - Spiral CT angiography and 3D reconstruction in patients with aortic coarctation. AB - The objective of this study was to assess the reliability of spiral CT angiography (CTA) and 3D reconstruction in patients with aortic coarctation (CoA). Eighteen patients with suspected or surgically proven coarctation were examined by spiral CT. In addition to the axial slices, 3D reconstructions, such as shaded surface display (SSD) and maximum intensity projection (MIP), were used to determine the diameters of the CoA and the pre- and poststenotic aorta and to visualise the collateral vessels. Diameters derived from cardiac catheterization were compared with those from CTA in 8 patients. The degree of aortic stenosis was correlated with blood pressure gradients (BPG) in 12 patients. The difference between the diameters of the CoA and the pre- and poststenotic aorta derived from MIP and angiography was not statistically significant (p = 0.69). With SSD the internal thoracic artery was detected in 16 and the posterior intercostal artery in 13 cases. The degree of aortic stenosis correlated poorly with the BPG (r = 0.51, r2 = 0.26). CTA with 3D reconstruction represents a reliable noninvasive technique for the assessment of the degree of CoA and the visualisation of collateral vessels. It may serve as a follow-up investigation after intervention or surgical treatment. PMID- 9369518 TI - Evaluation of myelination and myelination disorders with turbo inversion recovery magnetic resonance imaging. AB - The aim of our work was to determine the efficacy of turbo inversion recovery spin echo (TIRSE) pulse sequences in differentiating patients with normal and abnormal myelination. Twenty neurological normal children (aged 5 months to 12 years) as well as 65 children presenting clinically with neurologic developmental deficits (aged 2 months to 10 years) were examined using TIRSE, T1-weighted SE, and T2-weighted turbo SE pulse sequences. Contrast-to-noise-ratio (CNR) between myelinated white and gray matter was compared for the different pulse sequences. In addition, two readers analyzed all images qualitatively by consensus. The CNR values were significantly higher on TIRSE images as compared with conventional images (p < 0. 05). Forty-two neurologically abnormal patients displayed a normal myelination on all sequences, whereas 23 showed an abnormal myelination. The TIRSE sequence provided a sensitive and specific depiction of an abnormal myelination in all of these patients. The TIRSE sequence provided additional information to conventional pulse sequences in determining myelination disorders in children, especially in children older than 2 years. PMID- 9369519 TI - MR cisternography: a new method for the diagnosis of CSF fistulae. AB - The aim of this study was to compare a new MRI method for detecting the existence of cerebrospinal fluid (CSF) fistulae, i. e. MR cisternography, with CT cisternography. In a prospective study, 30 patients with post-traumatic CSF fistulae were examined. The MR examinations were performed with a 1.0-T whole body MR system, using two T2(*)-weighted sequences, a 3D PSIF (time-inversed fast imaging with steady-state precession, FISP) and a 3D constructive interference steady-state (CISS) sequence. The results of MRI and CT cisternography were compared with the surgical findings. The sensitivity in detecting CSF fistulae with MR cisternography (PSIF: 89.9 %; CISS: 93.6 %) was higher than with CT cisternography (72.3 %). The sensitivity of CT cisternography at detecting CSF fistulae in patients with a size of dural lesion less than 2 mm or in patients with multiple dural lesions is significantly lower compared with the MR method. Although the localization of CSF fistulae always proved possible with MR cisternography, this could only be accomplished wih CT in 70 % of cases. The MR cisternography technique is a new examination method with a higher sensitivity for the detection of CSF fistulae than CT cisternography. The CISS technique is superior compared with PSIF and should be used in patients with high-flow CSF fistulas. PMID- 9369520 TI - Primitive hypoglossal artery: demonstration with digital subtraction-, MR- and CT angiography. AB - The primitive hypoglossal artery (PHA) is a rare persistent carotid-basilar anastomosis. Usually it is found incidentally on angiography, but detection may be of importance for patient management. In the presented case MR- and CT angiography, which to our knowledge have not yet been reported in PHA, provided important additional information. PMID- 9369521 TI - Magnetic resonance angiography and colour-Doppler sonography in the evaluation of abdominal aortic aneurysms. AB - This prospective study was aimed at comparing the diagnostic accuracy of magnetic resonance angiography (MRA) with colour-Doppler ultrasonography (colour-Doppler US) in the assessment of abdominal aortic aneurysms (AAA). Twenty patients with abdominal aortic aneurysms underwent MRA, colour-Doppler US, digital subtraction angiography (DSA) and CT. The MRA technique and colour-Doppler findings were compared with DSA as well as surgical and pathological findings, which were considered as the gold standard. In 6 patients who refused surgery, CT and DSA were considered as the gold standard. The MRA technique always correctly assessed the size and site of the aneurysms, the involvement of the renal and common iliac arteries, the course of the left renal vein, the thrombotic component and the calcifications. Colour-Doppler US always correctly assessed the size and site of the aneurysms, the thrombotic component and calcifications and the involvement of the iliac arteries. Our preliminary results suggest that MRA together with colour Doppler US represents a valid alternative to invasive imaging in the assessment of AAA. PMID- 9369522 TI - Percutaneous vascular access guided by color duplex sonography. AB - Color duplex sonography (CDS) is primarily applied as a diagnostic procedure. It has not yet established itself as an aid in punctures or other interventions. The aim of this study was to evaluate the value of CDS in arterial and venous vascular punctures. One hundred and sixty-five CDS-assisted vascular punctures were performed in a prospective study after three unsuccessful palpation-guided vasopunctures or in the absence of a palpable pulse. All CDS-assisted punctures were successful. The duration of each attempted puncture showed no statistically significant difference compared with the palpation-guided puncture technique. In the cases with three unsuccessful palpation-guided vascular punctures, the CDS assisted technique was successful after 1.66 attempts on the average. It is concluded that CDS-assisted vascular puncture is a fast and safe alternative for puncturing a pulseless vessel or for puncturing under difficult conditions. PMID- 9369523 TI - From Bertha Roentgen's hand to current medical imaging: one century of radiological progress. AB - From 1896 to 1996 radiology progressed at an amazing and unforeseen pace. The analysis of a few examples shows that these developments were due to a few groups and were enhanced by a close interaction between radiologists, physicists, engineers and manufacturers. Radiologists emphasize needs and are often able to suggest avenues for research; engineers exploit the basic discoveries of physicists and find new technologies. Manufacturers proceed from prototypes to instruments that can be built on an industrial scale at an affordable price. This system works efficiently only in a few developed countries. The gap between developing and developed countries is not narrowing and a large proportion of the world population has no access to adequate medical imaging. Very sophisticated imaging technologies used in industrialized countries are costly in terms of both money and human resources and in developing countries may usurp the limited assets that are needed for public health. Thus, the current challenge facing radiology is to take advantage of technological progress, firstly for building affordable and easy to maintain equipment giving images of sufficient quality, and secondly, through progress in telecommunications and computers, to improve medical education, telemedicine and build hospital networks. These networks will enable easier access to consultations with specialized radiologists and will give physicians the means of sharing their medical expertise. The aim is not only to narrow the gap but to provide a sufficient level of care in imaging medicine and radiotherapy throughout the world. This will only be achieved through a clear strategy and adequate human, technical and financial resources. The role of the radiological community, in particular ISR, RSNA and EAR, shall be crucial in this endeavour. PMID- 9369524 TI - Postgraduate radiology training in Japan. PMID- 9369525 TI - Amyloid beta-protein toxicity and oxidative stress in Alzheimer's disease. AB - Alzheimer's disease (AD) is a neurodegenerative disorder characterized by loss of memory and progressive decline of cognitive abilities. Although the pathogenesis of this disease is not known and is still under intensive investigation, there are several hypotheses which address certain aspects of the disease. This review focuses on the oxidative-stress hypothesis of AD and on novel antioxidative approaches to an effective neuroprotection for the prevention and therapy of this neurodegenerative disorder. The toxicity of the AD-associated amyloid beta protein (Abeta), the induction of oxidative stress by Abeta in neurons, and potential sources of oxidative events in brain tissue are discussed. PMID- 9369526 TI - Plakophilins 1a and 1b: widespread nuclear proteins recruited in specific epithelial cells as desmosomal plaque components. AB - The cytokeratin-binding, basic 80.5 kDa polypeptide plakophilin 1 ("band 6 protein" of bovine muzzle desmosome fractions) has originally been described as a single molecular species, localized to desmosomal plaques of certain cell types, mostly stratified squamous epithelia and complex epithelia. We now report that this protein exists in at least two different isoforms: 726 amino acids (aa), plakophilin 1a; and 747 aa, plakophilin 1b. This reflects the splicing of the 21 aa-encoding exon 7 of the human plakophilin-1 gene and that each mRNA splice form can occur in two polyadenylation forms of 2.7 kb and 5.3 kb. Antibodies recognizing either isoform and/or others that are specific for the exon-encoded sequence of form 1b have allowed, in combination with immunolocalization protocols minimizing losses of diffusible proteins, the detection of both isoforms in the nucleoplasm of diverse kinds of cultured cells and tissues, including desmosome-forming cells as well as cells that never form desmosomes. The protein has also been identified in manually isolated nuclei (germinal vesicles) of Xenopus laevis oocytes. Plakophilin 1a accumulates in nuclei as shown by suitable immunolocalization protocols and upon overexpression following transfection with cDNAs, but is also located in desmosomes of stratified and complex epithelia. By contrast, isoform 1b has been found exclusively in nuclei, even in cells connected by desmosomes immunostained with plakophilin 1a-reactive antibodies. We conclude that plakophilins 1a and 1b are constitutive nuclear proteins encoded by the same gene, which is not expressed in relation to epithelial differentiation pathways, whereas the additional appearance of plakophilin 1a in desmosomal plaques of stratified and complex epithelia is regulated by an as yet unknown mechanism of differentiation-dependent topogenic recruitment. Possible functions of plakophilins are discussed in relation to recent reports of the involvement of other members of the armadillo/plakoglobin multigene family of proteins in cell surface-gene regulation signalling pathways. PMID- 9369527 TI - Immunocytochemical analysis of the transport of arginine analogues into nitrergic neurons and other cells in the retina and pituitary. AB - Nitric oxide is formed by the action of nitric oxide synthase upon l-arginine. The efficacy of some exogenously applied arginine analogues in inhibiting nitric oxide synthase and thus nitrergic transmission indicates that neurons producing nitric oxide may possess an arginine transport system. To investigate whether arginine analogues are preferentially transported into nitric oxide-utilising cells or into cells making other neurochemicals, we have raised highly specific antisera against a number of arginine analogues including NG-methyl arginine, D arginine, NGnitro-L-arginine, NG-nitro-L-arginine methyl ester and canavanine. Retinae were incubated in physiological media containing these analogues and rats were given intraperitoneal injections of the analogues to study the pituitary. Immunocytochemistry and NADPH-diaphorase histochemistry revealed that many of these analogues could be transported preferentially, but not exclusively, into nitric oxide-generating cells. However, some nitric oxide-producing cells apparently lacked the ability to take up some arginine analogues. We conclude that nitric oxide-generating cells in the retina and pituitary possess one or more arginine transporters. Other subsets of neurons that use GABA or glutamate as a neurotransmitter may also accumulate arginine analogues, possibly as a substrate for formation of these neurochemicals. PMID- 9369528 TI - TGF-beta receptor type II and fetuin in the developing sheep neocortex. AB - Fetuin shows a characteristic pattern of distribution in the developing neocortex in many mammalian species. Its expression is confined to early-appearing cortical plate and later subplate neurons. A short 19 amino-acid sequence of fetuin shows a degree of homology to an 18 amino-acid sequence of the TGF-beta type II receptor (TbetaR-II) and in vitro fetuin binds to members of the TGF-beta family of cytokines. It has been suggested that fetuin is the biologically significant antagonist of these cytokines. We have compared, using immunocytochemistry, the distribution pattern of TbetaR-II and fetuin in the developing neocortex of foetal sheep. TbetaR-II immunoreactivity first appears at around 40 days of gestation in the fetal sheep (E40, term in sheep is 150 days from conception), localised in two discreet bands: one just outside the cortical plate in the inner part of the marginal zone and one deep in the cortical plate in what becomes the transient subplate zone. By E70-E80, TbetaR-II is prominent in a population of subplate cells, whereas, by E120 only small patches of TbetaR-II-positive cells are visible, principally in pyramidal cells in layer VI. The developmental sequence of the staining pattern for TbetaR-II in the neocortex is complementary to that for fetuin, rather than overlapping with it. Double-labelling of fetuin and TbetaR-II shows some cellular co-localisation, especially at E60, but most fetuin-positive cells are not immunoreactive for TbetaR-II. Thus, fetuin's proposed role as an antagonist of TGF-beta cytokines and mimic of TbetaR-II is not consistent with the observed distribution of these two molecules in the developing neocortex of the foetal sheep. PMID- 9369529 TI - Heat shock protein 70 in the retina of Xenopus laevis, in vivo and in vitro: effect of metabolic stress. AB - We utilized the frog eyecup as an in vitro model to compare heat-shock protein 70 (hsp70) synthesis in untreated retinas and in hyperthermia-, arsenite-, or glutamate-treated retinas. Hsp70-like immunoreactivity in vivo was concentrated in the photoreceptors in a pattern that was basically unchanged throughout the light/dark cycle. Retinas from eyecups in culture displayed the same immunoreactivity pattern as those in vivo except for a rapid, transient increase in immunoreactivity surrounding the photoreceptor nuclei. The immunoreactivity pattern in heat-treated retinas was similar to that of controls, but overall intensity was greatest in the outer plexiform layer. Arsenite-treated retinas displayed hsp70-like immunoreactivity in a pattern that was also like that of control retinas. Glutamate exposure resulted in increased hsp70-like immunoreactivity not only in the inner segments and outer plexiform layer, but also in photoreceptor nuclei. Gel fluorography of 35S-methionine-labeled proteins from heat- and arsenite-stressed retinas demonstrated increased synthesis of one or two proteins of approximately 70 kD and one protein of approximately 90 kD. Exposure of eyecups to glutamate did not result in detectable changes in protein synthesis. Following exposure to heat or glutamate, the retinas displayed swelling of the inner plexiform layer (IPL) as well as pyknotic nuclei in the inner nuclear layer. Exposure of eyecups to arsenite caused clumping of the melanin granules of the retinal pigmented epithelium (RPE) but not IPL swelling or pyknotic nuclei. We have shown that the stress response can be manipulated successfully in the in vitro Xenopus retina and that the pattern of the response depends on the nature of the stressor. PMID- 9369530 TI - Exocytotic proteins in enterochromaffin-like (ECL) cells of the rat stomach. AB - Proteins participating in vesicular docking and fusion have been identified in the nervous system. Such proteins appear to be important for the molecular regulation of exocytosis also in non-neuronal cells. The enterochromaffin-like (ECL) cells of the gastric acid-secreting (oxyntic) mucosa secrete histamine and chromogranin A-derived peptides, such as pancreastatin. Using immunohistochemistry, we have examined whether the ECL cells of the rat stomach, identified with antibodies to histidine decarboxylase (HDC, the histamine-forming enzyme), express the same exocytotic proteins as neurons. The ECL cells displayed immunoreactivity for synaptophysin, synaptotagmin III, vesicle-associated membrane protein-2 (VAMP-2), cysteine string protein (CSP), vesicular monoamine transporter-2 (VMAT-2), synaptosomal-associated protein of 25 kDa (SNAP-25), syntaxin, and Munc-18, but not for synaptotagmin I/II and VAMP-1. Synaptophysin and VMAT-2 could be detected not only in the ECL cells, but also in a population of HDC-negative cells. The demonstration of synaptotagmin III in only a limited number of ECL cells suggests the existence of a subpopulation of ECL cells. The results show that several exocytotic proteins, previously identified in neurons, are present in rat stomach ECL cells. Hence, proteins engaged in vesicular docking and in the fusion of granule/vesicle membrane with plasma membrane seem to exist in both neurons and endocrine cells. PMID- 9369531 TI - Effects of postnatal age and of thymectomy on hamster pulmonary neuroendocrine system and aspects of programmed cell death. AB - Effects of postnatal age and neonatal thymectomy on the numbers and characteristics of pulmonary neuroepithelial bodies (NEB) were investigated in 14 day- compared with 2.5-month-old hamsters. Left lung sections were stained for the marker PGP 9.5 and used for light-microscopic quantification, while the right lungs were processed for an electron-microscopic survey of the NEB ultrastructural features. For the first time, it is clearly demonstrated that, depending on the sampling method, the number of NEB may rise or fall with age; when considering the entire lung volume, the actual number of NEB doubles, whereas when studying a constant surface area, their number apparently decreases. Also, the proportion of alveolar NEB as well as luminal contact increase on normal development. In neonates, in contrast to older animals, apoptosis is clearly present in NEB, and approximately 10% of the NEB are associated with inflammatory cells. In some cases, the dead cells have properties of both apoptosis, disintegration and cytoplasmic degeneration. The presence of intracorpuscular neutrophilic granulocytes correlates with cellular death and innervation of the NEB. Thymectomy causes only minor effects on the pulmonary neuroendocrine system. It is argued that development of the NEB and of their innervation continue during the postnatal period. PMID- 9369532 TI - Cellular expression of neurotrophin mRNAs during tooth development. AB - Target-derived neurotrophins support and sustain peripheral sensory neurons during development. In addition, it has been suggested that these growth factors could have developmental functions in non-neuronal tissues. To further elucidate the possible roles of neurotrophins in tooth morphogenesis and innervation, we have used in-situ hybridization to determine the specific sites of neurotrophin gene activity in pre- and postnatal rat jaws from E16 to P7. All four neurotrophins were expressed during tooth development with specific temporospatial patterns. Nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) mRNAs were mainly detected in the dental papilla/pulp in postnatal animals, and the pattern of expression correlated with the onset of dental innervation. In contrast, neurotrophin 3 (NT3) and neurotrophin 4 (NT4) mRNA expression patterns were predominantly epithelial and were strongest during early developmental stages when teeth are not yet innervated. Dental papilla NGF-mRNA expression was first seen in both epithelium and mesenchyme and later shifted to the odontoblast layer and the subodontoblast zone. BDNF-mRNA labeling was present in low levels in the early dental organ, but increased in the pulp and in the odontoblast cell layer of the developing teeth at later developmental stages. Both NT3 and NT4 mRNA were observed in the prenatal oral epithelium and the inner dental epithelium. NT3-mRNA labeling was seen mainly in the cervical loop region, fissure system depressions and cuspal tops, while NT4 mRNA was more evenly distributed in the dental epithelium. At P7, NT3-mRNA labeling was below detection level and NT4 mRNA expression was lower than at prior stages. Complementary to reports on the presence of low-affinity neurotrophin receptor (LANR), trkB and trkC mRNA in the developing teeth, our results suggest that neurotrophins may have multiple functions during tooth morphogenesis. Neurotrophins might participate in epithelial-mesenchymal interactions in early tooth morphogenetic events such as proliferation and differentiation of epithelial and mesenchymal cells. In addition, based on mRNA localization in postnatal animals, we also suggest that NGF and BDNF (beside glial cell line derived neurotrophic factor) might participate in establishing and maintaining the innervation of the teeth, thus acting as classical neurotrophic factors. PMID- 9369533 TI - Age-related differences in the temporal and spatial regulation of matrix metalloproteinases (MMPs) in normal skin and acute cutaneous wounds of healthy humans. AB - Despite the association of increasing age with chronic wound-healing disorders and an impaired rate of healing of acute cutaneous wounds, the role of matrix metalloproteinases (MMPs) is unknown. To determine the spatial and temporal patterns and activities of MMP-1, -2, -3 and -9, 132 healthy humans aged between 19 and 96 years underwent 4-mm punch biopsies followed by wound excision between day 1 and day 180 post-wounding. Wounds showed an age-related increase in MMP-2 and MMP-9 immunostaining from day 3; this was associated with degradation of gelatin as shown by zymograms and with increased proteinase activity as shown by azocoll assays. Distinct spatial localisations for each MMP were observed: MMP-2 was found in epidermal structures; MMP-9 was observed in inflammatory cells up to day 21; MMP-1 was localised to keratinocytes at the wound margin. Normal old skin showed pro-MMP-2 bands on zymography and increased MMP-2 immunostaining. These results indicate that: (1) intrinsic ageing is associated with the up-regulation of MMPs previously associated with chronic wound healing; (2) wound-tissue proteinases are essentially active up to day 21 postwounding; and (3) intrinsic ageing may predispose to tissue breakdown disorders because of MMP-2 up regulation in normal skin. PMID- 9369534 TI - The fibroblast-specific MAb AS02: a novel tool for detection and elimination of human fibroblasts. AB - The unwelcome presence of fibroblasts in many cell cultures prevents the long term cultivation of various cell types and work with pure populations. Recently, we described a novel fibroblast-specific monoclonal antibody (MAb AS02) that recognises a membrane-bound antigen. We have now developed a method using the fibroblast-specific MAb AS02 immobilised on goat-anti-mouse-magnetic beads to separate contaminating fibroblasts. An endothelial cell line experimentally contaminated with 5%-50% fibroblasts was successfully purified. Additionally, an endothelial cell line with an initial fibroblast contamination of 1.5% was prepared. A proportion of each preparation was cultured with no separation step being performed, whereas the remainder was cultured after purification with MAb AS02 to exclude the presence of a minor number of fibroblasts (<0.1%). The proportion of fibroblasts increased up to 38% in the fifth passage of culture without elimination of the low initial fibroblast contamination, whereas in the fraction with the separation step, no fibroblasts were detectable by flow cytometry, even after the fifth passage. We also used the antibody to detect the presence of naturally contaminating fibroblasts in thyrocyte cultures. After cultivation of thyrocyte cultures over five passages, the number of fibroblasts increased dramatically up to 50%-80% of the whole population. Subsequently, we successfully applied the method for complete elimination of naturally contaminating fibroblasts from freshly isolated thyrocyte cultures from enzymatically digested thyroid glands. Thus, MAb AS02 is a fibroblast-specific marker that is a useful tool for the detection and elimination of contaminating fibroblasts. The specificity of MAb AS02 permits the universal application of this antibody for human cell cultures of interest. PMID- 9369535 TI - Molecular anatomy of the perivascular sheath in human placental stem villi: the contractile apparatus and its association to the extracellular matrix. AB - In previous studies, we have shown that smooth muscle cells and myofibroblast subpopulations of the perivascular stem villous sheath of the human placenta contain focal adhesion plaques and talin immunoreactivity. The close association of these cells to elastic and collagen fibres have led to the assumption of a functional myofibroelastic unit within the perivascular stem villous sheath. Interactions between the extracellular matrix and smooth muscle cells depend on a variety of structural protein assemblies. In the present study, we examined, by immunocytochemistry, whether the molecular assembly of extracellular matrix proteins and molecules of focal adhesions, known to be essential for signal transduction in smooth muscle cells, are also found in smooth muscle cells of the perivascular stem villous sheath of the human placenta. Vascular and extravascular smooth muscle cells were immunoreactive for alpha-actinin, vinculin, paxillin and tensin, the integrin chains alpha1 and beta1, and the basement membrane components laminin and heparan/-chondroitin sulfate proteoglycan perlecan. pp125(FAK) did not react. In the extracellular matrix of blood vessel walls and the perivascular stem villous sheath, we found immunoreactivity of fibronectin and collagen types I, VI and undulin (collagen type XIV). From our data we conclude that within the perivascular stem villous sheath, there exists a system of signal transduction molecules, indicating a cross talk between the smooth muscle cells of this sheath and their surrounding extracellular matrix. PMID- 9369536 TI - Thymic aging in ICR female mice is suspended by prolonged hydrocortisone exposure. AB - Age-related decline of the thymus in ICR female mice was studied following long term (three month) weekly exposure to hydrocortisone acetate. When examined one week after cortisone injections, the well-known thymic atrophy was observed. Five weeks after 12 hydrocortisone injections, the cortical volume fraction (Vc), cortical/medullary ratio (C/M), the number of thymocytes and CD4/CD8 profiles were in the range that characterizes younger mice, compared with PBS-injected mice, uninjected controls, or mice given a single hydrocortisone injection 5 weeks earlier. It seems as if thymic involution with age was suspended during the period of glucocorticoid exposure. PMID- 9369537 TI - Ultrastructural localization of relaxin in the corpus luteum of the pregnant and early lactating tammar wallaby, Macropus eugenii. AB - Electron-microscope immunocytochemistry was used to determine the subcellular distribution and presence of immunoreactive relaxin throughout pregnancy and early lactation in the corpus luteum of a marsupial, the tammar wallaby. Membrane bound, electron-dense granules were a prominent feature of the luteal cell cytoplasm. The highest numbers of granules were observed between days 20 and 24 of the 26-day gestation, with a rapid clearance immediately after birth. Relaxin immunogold particles were present only in small, electron-dense granules (200-350 nm in diameter), with no particles observed in larger granules (>400 nm diameter), nuclei or mitochondria. Relaxin immunoreactivity was low throughout early and mid pregnancy but increased markedly between days 21 and 22 and remained high over the last 4 days of pregnancy. The number of granules containing relaxin immunogold particles and the density of immunostaining were both reduced on the day of expected births (day 26). Our data demonstrate that electron-dense granules in the luteal cell cytoplasm of a pregnant marsupial contain relaxin. The peptide is produced in greatest amounts at the end of pregnancy, consistent with a role in parturition. PMID- 9369538 TI - Platelet/endothelial cell adhesion molecule-1 (PECAM-1) is localized over the entire plasma membrane of endothelial cells. AB - The subcellular localization of PECAM-1 in endothelial cells was examined by using advanced morphological techniques, such as confocal scanning microscopy and immunolabeling procedures for electron microscopy. The localization of PECAM-1 was studied immunohistochemically with five specific monoclonal antibodies and one polyclonal antibody (all anti-human) in human and rabbit myocardium and in isolated endothelial cells. In vivo, PECAM-1 was localized uniformly on the plasma membrane of all vascular endothelial cells, predominantly on the luminal side of vessels. No specific increase in labeling was found at sites of cell-to cell contact. In vitro, primary isolated cells (human umbilical vein endothelial cells) showed continuous labeling of the entire cell membrane. Cells of higher passages were labeled in a manner similar to freshly isolated cells. Our findings refute the commonly accepted hypothesis that PECAM-1 is localized only at cell-to cell contacts. Further, we have not been able to confirm the hypothesis regarding the important mechanical role of PECAM-1 in stabilizing the endothelial monolayer. Since PECAM-1 is also expressed on platelets and is known to bind to itself, the way in which PECAM-1-positive endothelial cells are protected against binding of PECAM-1-positive platelets remains unclear. In view of these findings, the role of PECAM-1 in the leukocyte migration cascade needs to be re-evaluated. PMID- 9369540 TI - The peripheral branching pattern of identified dorsal unpaired median (DUM) neurones of the locust AB - Identified dorsal unpaired median (DUM) neurones of the locust Locusta migratoria were stained intracellularly with large amounts of cobalt to reveal their extensive peripheral branching patterns. Two neurones of the suboesophageal ganglion were studied as well as several neurones of thoracic ganglia. The peripheral branching pattern of all these neurones is described completely. As expected, the prevalent target organs of all DUM neurones are skeletal muscles. In addition several, but not all DUM neurones studied here form neurohaemal release sites on the surface of peripheral nerves and thus represent potential sources for octopamine acting as a neurohormone. PMID- 9369539 TI - Immuno-electron microscopy reveals that the excitotoxin quinolinate is associated with the plasma membrane in human peripheral blood monocytes/macrophages. AB - Quinolinate (QUIN), a tryptophan-derived excitotoxin, was localized ultrastructurally in human peripheral blood monocytes/macrophages (MO) by immuno electron microscopy. A combined carbodiimide/glutaraldehyde/paraformaldehyde based fixation procedure was developed for optimal retention of QUIN in the cell as well as minimal loss of ultrastructure; a silver-enhanced colloidal gold detection system was used for electron-microscopic analysis. Gold particles representing QUIN immunoreactivity were associated with the inner side of the plasma membrane in normal MO. The number of gold particles increased significantly when QUIN levels were elevated by treatment with its precursor kynurenine, but location of the gold particles remained essentially the same under this condition. Treatment with interferon-gamma increased the number of Golgi bodies, vacuoles and pseudopodia, reflecting the activated state of the cell. Significantly increased numbers of gold particles representing QUIN were detectable in approximately the same location as in the case of kynurenine treatment. Combined treatment with kynurenine and interferon-gamma maximally increased the number of gold particles at the periphery of the cell. The pseudopodia were intensely stained with gold particles, while they were not detectable in the inner part of the cytoplasm or in any other organelle even under this activated condition. The significance of the specific location of QUIN revealed in the present study and its relation to the release and subsequent actions of QUIN are discussed. PMID- 9369541 TI - The peroxisomes of the hepatopancreas in two species of chitons AB - . This paper presents the first description of peroxisomes in polyplacophorans. As in other molluscs, the hepatopancreas of chitons is composed of basophilic and digestive cells. In the basophilic cells, the endoplasmic reticulum is abundant and several Golgi stacks can be observed. These cells also possess secretion granules and vacuoles with spherites. The digestive cells are mainly characterized by the presence of many food vacuoles. Several peroxisomes were observed in the basophilic cells of Acanthochiton crinita, most of them almost spherical. The matrix is filled with tubular structures and a crystalline nucleoid is also present in these organelles. In the digestive cells of A. crinita, peroxisomes are also almost spherical and possess two kinds of nucleoids. One of them presents a diamond shape and a bundle of tubular structures forms a second kind of nucleoid, which shows an elongated form. In Lepidochitona cinerea, the peroxisomes of basophilic cells are spherical or oval. Within the matrix, a cluster of dense rods and a prismatic nucleoid were observed. In the digestive cells of this species, almost spherical or oval peroxisomes are common, but they are smaller than the peroxisomes of the preceding cells. Nucleoids were not detected, but a few dense rods could be observed in the matrix. In both cell types of the two species, catalase activity was detected in the peroxisomal matrix. In addition, the elongated nucleoid of A. crinita digestive-cell peroxisomes and the nucleoid of L. cinerea basophilic-cell peroxisomes also present catalase activity. PMID- 9369543 TI - Occurrence of binding sites for [125I] ANP in the myocardium but not in Purkinje fibers of the bovine heart. AB - Atrial natriuretic peptide has frequently been detected in the cardiac conduction system and has been shown to regulate some intracellular effects in Purkinje fibers. To determine if atrial natriuretic peptide works as an autocrine and/or paracrine hormone on cardiac Purkinje fibers, we examined the different parts of the conduction system in the bovine heart by use of in vitro receptor autoradiography. In no parts of the bovine conduction system were specific binding sites for [125I] atrial natriuretic peptide observed, whereas the ventricular myocardium exhibited a large number of [125I] atrial natriuretic peptide binding sites. This is the first morphologic study showing the presence of [125I] atrial natriuretic peptide binding sites in the ventricular myocardium and their absence in the conduction system. The present observations together with results obtained in studies using other methods strongly suggest that natriuretic peptide receptors are localized on ventricular myocytes. PMID- 9369542 TI - Neuropeptide Y in the infundibular nucleus and hypophysis of great apes. AB - We studied the distribution of neuropeptide Y (NPY) immunoreactivity in the infundibular nucleus and the hypophysis of the chimpanzee, gorilla, and orangutan. Using antibodies developed in rabbit against synthetic porcine NPY, we found numerous NPY-immunoreactive neuronal somata in the infundibular nucleus; this nucleus was also filled with short NPY-positive processes and an abundance of punctate structures that could be indicative of synaptic terminals. Numerous varicose NPY-positive fibers were concentrated in the upper infundibular stem in association with capillary loops of the portal vasculature and with the long portal vessels. Bundles of long varicose fibers ran down the infundibular stem, some appearing to terminate in the lower stem in the vicinity of short portal vessels. The bulbous infundibular process contained only sparsely distributed fibers; they were mostly concentrated near vessels at the border between the infundibular process and the anterior pituitary gland, where the fibers often terminated in a spray-like fashion near blood vessels. No NPY immunoreactivity was seen in the anterior pituitary gland. These results provide anatomical evidence for the release of NPY into the portal vasculature of great apes. PMID- 9369545 TI - Management of tissue load: An excerpt from the third NPUAP Slide Set. National Pressure Ulcer Advisory Panel. AB - In 1994, the Agency for Health Care Policy and Research (AHCPR) published Treatment of Pressure Ulcers, a clinical practice guideline that provides a comprehensive program for treating individuals with Stages II through IV pressure ulcers. The treatment program outlined in the AHCPR treatment guideline includes: assessment of the patient and pressure ulcer(s), tissue load management, ulcer care, management of bacterial colonization and infection, consideration of operative repair, and education and quality improvement. This excerpt from the NPUAP CE Program 2 (Slide Set #3) addresses issues related to tissue load management such as positioning and repositioning, head-of-the-bed elevation, selection of support surfaces, and moisture considerations. PMID- 9369544 TI - The role of skin blood flow in pressure ulcer development during surgery. AB - Laser Doppler flowmetry was used to examine the relationships between skin blood flow and pressure ulcer development. Blood flow in the skin over the iliac and sacral bony prominences was measured intraoperatively in 24 consecutive patients undergoing lengthy surgical procedures. Patients who did not develop pressure ulcers postoperatively had a 500% mean increase in blood flow during the procedure as compared with the preoperative levels. Blood flow levels decreased during surgery in patients who developed pressure ulcers postoperatively. There was no statistical difference in the lengths of surgery between the two groups. These results suggest that the body's failure to increase blood flow in response to extended pressure during surgery may contribute to pressure ulcer development. PMID- 9369546 TI - Symbols of hope. PMID- 9369547 TI - Population studied not typical. PMID- 9369548 TI - Supporting women during breast diagnostics. AB - Breast cancer is the most frequently diagnosed cancer among Canadian women. It is estimated that, in 1997, there will be 18,400 new cases of breast cancer and 5,100 breast cancer deaths among Canadian women; one in nine Canadian women will develop breast cancer at some time in their lives. PMID- 9369549 TI - Physical punishment: an unnecessary risk to children. AB - Using physical punishment to control, guide or correct the behavior of children has long been practised in Western culture. "Spare the rod and spoil the child," recite its advocates, both misquoting and misinterpreting the biblical proverb. In recent years, child care experts, health care practitioners and parents have begun questioning the practice of physical punishment and considering its role in child abuse. Child abuse, a form of family violence, is a major public health issue with far-reaching effects and costs and many implications for health policy, prevention and promotion strategies. Because nurses are often called upon to provide guidance and advice on parenting and discipline, we should be aware of the issues and risks of physically punishing children. PMID- 9369550 TI - Breastfeeding: a course for health professionals. AB - Breastfeeding advocates say that breastfeeding is health promotion in its purest form. Its considerable health benefits to the infant and the mother are well documented. Recent research has identified breastfeeding as a key factor in the prevention of sudden infant death syndrome and increased cognitive functioning. As a method of feeding, breastfeeding offers immediate economic advantages to the parents and long term economic savings to society. One author reports that the exclusive breastfeeding of infants for four months could save the Province of Ontario at least $862,000 a year just by reducing the need for the treatment of otitis media. Another researcher calculated the cost of treating 150 bottle-fed babies hospitalized for gastroenteritis at $450,000 Canadian, while reminding us that "hospitalization for gastroenteritis is almost unknown for exclusively breastfed infants." With all these known benefits, why is breastfeeding not more prevalent among Canadian mothers? PMID- 9369551 TI - Lessons from Mary Lou. PMID- 9369552 TI - Breast cancer resources online. AB - It used to be that breast cancer was shrouded in mystery. Those diagnosed with the disease had difficulty finding information or even knowing where to look for it. Gladly, times have changed. Growing awareness of the disease has been accompanied by a growth in related resources. Much of the information is provided by those who have experienced breast cancer firsthand. PMID- 9369553 TI - A question of values. AB - Health care reform has increased efforts by researchers and policy makers to search for more conclusive evidence on what works and what doesn't in health care. Considerable attention is being given to reducing inefficiencies in the system and ensuring that only cost-effective programs are funded. PMID- 9369554 TI - [Peritoneal equilibration test and its operation on CAPD patients]. AB - In order to observe the transport ability of peritoneum to small molecular substances, peritoneal equilibration test (PET) was performed in 52 CAPD patients. By analysing the relationship between peritoneal transport function and dialysis adequacy, we found the average urea KT/V and Cr were significantly lower in high and low transport groups (n = 6 and n = 2) than in high average and low average groups (n = 35 and n = 9). According to the results of PET, we adjusted the dialysis program of 11 patients and the dialysis adequacy was markedly improved. We concluded that PET was helpful for selecting and adjusting CAPD program, and discussed some questions which should be payed more attention in PET operation. PMID- 9369555 TI - [Language rehabilitative training for postoperative aphasia in neurosurgery]. AB - Rehabilitation nursing focus on assisting patients to reconstruct their health. We trained 21 cases of aphasia after operation with different types of early comprehensive speech reconstruction exercises, including hearing, speaking, reading and writing. We achieved expected results. Anomia aphasia has the best outcome, next is motor and sensory aphasia, and combined aphasia is less effective. In addition, patients with aphasia before surgery got slightly better rehabilitation than those whose aphasia was resulted from surgery. PMID- 9369556 TI - [Reasons of failure in blocking mother-infant transmission of HBV by using vaccine and related strategies]. AB - We have detected the serum marker of HBV of 32 mothers whose HBsAg present positive and their children whom were given Hepatitis B vaccine immunization throughout duration of their mothers' pregnancy, altogether making up 66 cases. In 3 of these 32 families, Hepatitis B vaccine failed to block transmission between mother and infant. Direct nucleotide sequence analysis of HBV were carried out in 7 HBsAg positive infected persons. To confirm the possibility of HBV transmission between mother and infant on molecular level, we used PCR technique and DNA sequencing method. The reasons of which HBV vaccine failed in blocking transmission were discussed at the point of views of virus variation. Besides, we make and emphasized discussion on how to tighten up the measurement of controlling the course of infection and protecting susceptible population. PMID- 9369557 TI - [The observation on the disinfecting efficiency of the disinfectant 93]. AB - Disinfectant 93 is a colorless and transparent liquid. It contains surfactant and hand-protective. Its major component is Di(octyl amino-ethyl) glycine hydrochloride. 99.8% natural bacteria could be removed from the medical staff's hands by using the disinfectant 93 to scrub for 1 min twice. According to the standard of the Ministry of Public Health, it is allowed that the amount of bacteria on the hands is less than equal to 10cfu/cm2 under the condition of class III, and less than equal to 5cfu/cm2 under the condition of class I [symbol: see text] II, in which the qualification rate reached to 100% and 98%, respectively. The average elimination rate of natural bacteria reached to 99.5% and 99.3%, when the hands of surgical operators were disinfected with the disinfectant 93 after scrubbing and brushing with soap. The results showed that disinfecting efficiency of the disinfectant 93 was stronger, its continued effects were also visible, and it wasn't irritative for skin. PMID- 9369558 TI - [Clinical features and treatment of hemoperitoneum in continuous ambulatory peritoneal dialysis patients]. PMID- 9369559 TI - [Nursing care of pediatric burn patients with septicemia and convulsions]. PMID- 9369560 TI - [Care of phosphorus poisoning following phosphorus]. PMID- 9369561 TI - [Nursing care of mixed pulp autoepidermis and autodermis grafts on deeper donor wounds]. PMID- 9369562 TI - [Nursing care of children after cystostomy]. PMID- 9369563 TI - [Urinary function after gastrocystoplasty]. PMID- 9369564 TI - [Analysis and nursing care of extrapyramidal reactions caused by antipsychotics in 75 cases]. PMID- 9369565 TI - [Analysis and nursing care of vasa praevia in cord velamentous insertion]. PMID- 9369566 TI - [Breast feeding reduces the physiological weight loss of the newborn]. PMID- 9369567 TI - [Early use of tracheal and umbilical vein intubation for the treatment neonatal asphyxia]. PMID- 9369568 TI - [Relationship between psychoactive drug treatment and nosocomial infection]. PMID- 9369569 TI - [Nursing administration for foreigners--analysis of the experience]. PMID- 9369571 TI - [Progress in nursing care of patients after laryngeal surgery]. PMID- 9369570 TI - [Training of heart surgery operating room nurses: retrospective study of 68 nurses]. PMID- 9369572 TI - Screening RN members for good character. PMID- 9369573 TI - Guidelines for acceptable employment to maintain eligibility for registration with the Saskatchewan Registered Nurses' Association. PMID- 9369574 TI - Health Liaison Worker Pilot Project: a joint venture between the Meadow Lake Tribal Council and the Northwest Health District. PMID- 9369575 TI - Saskatchewan Heart Health Program. Part II: Demonstration phase. Saskatchewan Heart Health Coalition. PMID- 9369576 TI - Investigation results of seniors and health-professionals' perceptions and communication about prescriptions and alternate therapies. PMID- 9369577 TI - The faults in no-fault insurance. PMID- 9369578 TI - [Sedation and analgesia in a surgical intensive care unit]. PMID- 9369579 TI - [Nursing evaluation of the effect of the type of sedation on the degree of anxiety in patients undergoing cardiac surgery]. AB - The objective of this work is to identify the degree of preoperatory anxiety which patients who must undergo cardiac surgery present, and evaluate the influence of sedation with Propofol or Midazolam in the appearance of anxiety in the immediate and late postoperatory. The study population was formed by 22 patients, being appointed at random to receive Propofol or Midazolam in infusions. We used the scale of Max Hamilton in three consecutive stages (preoperatory, post-extubation, and pre-discharge) to measure the level of anxiety. Both groups were similar according to their distribution in sex, age, weight, conscience level and severity level at entrance. The patients who were sedated with propofol showed a level of postoperatory anxiety significatively lower than those patients who were treated with midazolam (p < 0.05). To conclude, we believe that the type of sedative used has a significant influence in the development of post-operatory anxiety. PMID- 9369580 TI - [Tracheostomy in the intensive care unit]. AB - During the last 22 months, a total number of 85 tracheostomies have been performed in our ICU, 40 of which have been surgical, and 45 percutaneous to patients under mechanical ventilation. This period has coincided with the learning process of the technique of percutaneous tracheostomy by our staff. The choice of the type of tracheostomy was not taken at random, but guided by clinical criteria. Our results confirm a lower rate of infection of the estoma in percutaneous tracheostomies than in surgical ones (5 percutaneous and 29 surgical, p < 0.001). The most serious complication was a tracheal perforation in a percutaneous tracheostomy. 17 of the 85 patients died in ICU, and 33 of the 68 patients who were discharged, survived the hospital, 27 of whom left with a closed tracheostomy. The other 6 permanent tracheostomies had been performed surgically and corresponded to 4 patients with worsening EPOC, one neurological patient and another patient suffering from anoxic encephalopathy. No percutaneous tracheostomy was left as permanent. The patients who benefitted especially from the tracheostomy presented the following characteristics: acute respiratory insufficiency with prolonged intubation, neurological patients, and worsening EPOC. The tracheostomy in persistent vegetative status allowed their moving to more suitable areas. Our study proves the existence of a learning curve in the practice of percutaneous tracheostomy. This aspect should be taken into account by other groups who are interested in including this technique in their services. PMID- 9369581 TI - [Tolerance for enteral nutrition in critical patients. Results of a nursing protocol]. PMID- 9369582 TI - [Intensive care nursing 1988-1997. Balance sheet of an epoch]. PMID- 9369583 TI - Cultural assessment in home healthcare. AB - As the nurse becomes adept at performing cultural assessments and culturally competent care, it will become clear that "although it is critical to conduct a cultural assessment with culturally and ethnically diverse groups, it is also important to realize that every client needs a cultural assessment. Every client has values, beliefs, and practices that must be considered when a clinician renders healthcare services. Therefore, cultural assessments are not limited to specific ethnic groups, but rather should be conducted on each individual" (Campinha-Bacote, 1995, p.148). Nurses who have been identified as good transcultural nurses have been found to be empathetic, caring, open, and flexible. They have a positive attitude toward cultural differences and have a genuine interest in learning from the client about the client's culture (Emerson, 1995). Talabere (1996) states that openness, appreciation of another's perspective, holistic communication, genuine interest, and a nonjudgmental attitude are central to cultural sensitivity. When a culturally sensitive nurse develops mutually agreeable goals with a patient from another culture, a kind of cultural synergy occurs, resulting in care that is "meaningful, satisfying and beneficial to clients" (Leininger, 1988, p.155). PMID- 9369584 TI - Contracted services survey process. PMID- 9369585 TI - Reflections of my cultural nursing experience in Mexico. AB - One home care nurse's experience in Mexico has meaning for her daily practice in Georgia. Other home care nurses will also profit from this nurse's insight into culturally diverse populations and the importance of delivering this care to all patients and families. PMID- 9369586 TI - A patient is more than the sum of the chart. PMID- 9369587 TI - The home healthcare nurse and assisted suicide. PMID- 9369588 TI - Visiting Nurse Service of New York celebrates multiculturalism. AB - Home health providers must develop culturally sensitive and specific programs for many populations. This article outlines the steps agencies and practitioners can take to design these programs. Examples of two specialty programs developed by the Visiting Nurse Service of New York, one focusing on the Jewish and Russian Jewish community and the other on the Asian Home Care Program, provide insight into the importance of a comprehensive approach to all cultural home care programs. PMID- 9369589 TI - Being aware of workplace abuse of home care aides. PMID- 9369590 TI - The art of seeing. AB - This article, written by a home care nurse from Norway, won the World Health Organization's Balint Prize for the field of health and nursing care in 1996. The author shares a compelling client situation illustrating that home care nurses throughout the world share many attributes, but the main one is caring. PMID- 9369591 TI - Home care in Changsha, the Peoples Republic of China: a view from the field. PMID- 9369592 TI - An invitation to The Netherlands. PMID- 9369593 TI - Community health nursing in Northern Ireland. PMID- 9369594 TI - Diabetes information you can use. PMID- 9369595 TI - Chronic subclinical hypothermia: home care alert. AB - Chronic subclinical hypothermia poses a serious challenge to home health nurses because the condition may negatively impact the plan of care for very old and frail clients. This article provides a review of age-associated changes in thermoregulation, discusses the ways in which these changes may affect an elderly client's response to care, and offers home care interventions for individuals with chronic subclinical hypothermia. PMID- 9369596 TI - Nurses: community actualizers. PMID- 9369597 TI - President's message. If I could reach.... PMID- 9369598 TI - Euthanasia, assisted suicide, and the right to die. PMID- 9369599 TI - Finnish emergency nurses group wishes to strengthen ties with international groups. PMID- 9369600 TI - More on injury prevention. PMID- 9369601 TI - More on progressive latex allergy syndrome. PMID- 9369602 TI - Natural rubber latex allergy. PMID- 9369603 TI - A fatal case of acid ingestion. PMID- 9369605 TI - Strategies to implement helmet legislation for child bicyclists. AB - Research in the area of injury prevention has shown that legislation combined with education is the most effective way to increase helmet use in child bicyclists. Legislative activities have been proven to reduce injuries. Nurses can join with other interested stakeholders to form community coalitions, to educate the public, and to influence public policy. PMID- 9369604 TI - Effect of a bicycle safety program and free bicycle helmet distribution on the use of bicycle helmets by elementary school children. AB - OBJECTIVE: Each year in the United States, 300,000 children are treated in emergency departments for bicycle injuries; one third have head injuries. The purpose of this study was to determine the effectiveness of educational interventions and free helmet distribution in increasing the use of helmets by elementary school children. METHODS: Self-report questionnaires on the use of bicycle helmets were used for students at two elementary schools (n = 1610). Testing was done both before and after the administration of a bicycle safety program and the distribution of free helmets. Pretest and posttest answers were then compared for changes in helmet use. RESULTS: Helmet usage increased significantly after the bicycle safety program, from 38% to 46% overall (p < 0.005). Children who were given free helmets were significantly more likely to wear their helmets (61.4%) than children who already owned helmets (43.4%) (p > 0.016). Children who attended the school in which free helmets were distributed showed a significant increase in helmet use (p < 0.01), whereas those at the school that had a safety program alone did not show a significant increase (p > 0.17). DISCUSSION: The results of this study suggest that bicycle safety programs and free helmet distribution may increase the consistent use of helmets in elementary school children. PMID- 9369606 TI - Resurgence of tuberculosis: implications for emergency nurses. AB - An emergency nurse is often the first person with contact with patients with suspected or known TB when they come to the emergency department. With rapid recognition of signs and symptoms of active TB and prompt implementation of precautions, emergency nurses can reduce the transmission of the "greatest killer of mankind" to other patients, visitors, health care workers, and ourselves. PMID- 9369607 TI - Asthma in the emergency department. PMID- 9369608 TI - Air bags: an update. AB - Overwhelming evidence shows that air bags save lives and reduce morbidity associated with MVCs. The resulting benefits far outweigh the risks of air bag injury or death. Emergency nurses play a pivotal role in educating the public about active seat belt use in conjunction with passive restraint systems such as air bags. Air bags cannot be viewed as a single solution or panacea to occupant protection. Air bags are designed as supplemental devices to be used with seat belts and require the active participation of the user for maximum benefit and safety. PMID- 9369610 TI - Emergency center follow-up program. PMID- 9369609 TI - Seven abdominal assessment signs every emergency nurse should know. PMID- 9369611 TI - Bogus heroin. PMID- 9369612 TI - Improved forensic documentation of genital injuries with colposcopy. PMID- 9369613 TI - Provider order entry: it can work! PMID- 9369614 TI - The duty to document--what are the limits! PMID- 9369615 TI - A look back: battle of the bulge. PMID- 9369616 TI - Designing and implementing a significant findings charting system in the pediatric emergency department. PMID- 9369617 TI - Writing a research abstract. AB - Research abstracts may be difficult to write, especially for novice researchers. Reading abstracts from previous ENA Scientific Assemblies with a critical eye will help you focus on the abstract elements described in this article. Your abstracts should be clear, logical, and grammatically correct. Having others (for example, clinical nurses and a nurse researcher) review your abstract and provide feedback before submission is also helpful. And, after your research abstract has been accepted and presented, it's still not over--the next step is writing the research manuscript! PMID- 9369618 TI - SANE program staff: selection, training, and salaries. PMID- 9369619 TI - Giving bad news compassionately: a 2-hour medical school educational program. PMID- 9369620 TI - A 19-year-old woman with unexplained weakness and dizziness. PMID- 9369621 TI - Camp Barnabas: enlarging the spirit, encouraging the heart--where children with special challenges can just be kids. PMID- 9369622 TI - Management of dialysis catheters. AB - The goals of dialytic therapy are to provide safe, effective care and to emphasize the continuous improvement of quality. To provide such effective care requires the availability of a functional dialysis access. This is a critical (and sometimes the most difficult) component of dialysis. Care should focus not only on the maintenance of function but also on the prevention of complications. This article will familiarize the healthcare professional with the types, uses, and management of peritoneal and hemodialysis catheters. PMID- 9369623 TI - Catheter pinch-off syndrome: recognition and management. AB - Catheter pinch-off syndrome is an uncommon and often unrecognized complication of central venous catheters. The cause, clinical diagnosis, and management of this unique catheter occlusion are reviewed. Nurses can play a key role in the early detection of catheter pinch-off syndrome as well as the prevention of subsequent catheter fracture and embolization. PMID- 9369624 TI - Adverse effects of transfusions caused by leukocytes. AB - The tremendous complexity of blood products gives rise to a range of adverse reactions. Transfusion reactions caused by leukocytes range from subtle and discomforting to dramatic and fatal. Although leukocyte-mediated events usually are harmful, some effects are beneficial. Leukoreduction can prevent most, but not all, adverse reactions. Awareness of the array of leukocyte-mediated transfusion complications and the appropriate preventive and therapeutic measures to be taken is a critical component of sound clinical transfusion practice. PMID- 9369625 TI - Intravenous conscious sedation in children. AB - More and more children undergoing both invasive and noninvasive procedures are receiving intravenous conscious sedation (IVCS). Medications including midazolam and fentanyl are used to provide both anxiety and pain relief, whereas barbiturates such as pentobarbital induce sleep for more sensitive studies including diagnostic imaging. An emphasis on proper staff education regarding airway management, medication delivery, patient assessment, and monitoring is essential for safe administration and care. In addition, planning should include preparation time for the patient and family. Adequate patient education as well as proficiency of the clinician enables IVCS to be delivered safely and effectively to achieve the desired outcome with limited risk to the patient. PMID- 9369627 TI - Decision matrix for selection of patients for a home infusion therapy program. AB - Managed care and escalating healthcare costs have affected all aspects of clinical practice. Today's practitioners must evaluate each patient and clinical situation to select the appropriate intravenous delivery venue to improve the chances of producing a satisfactory outcome. The IV venue discussed in this article will focus on the key elements of identifying patients who will benefit from receiving pharmacomedical services in a home infusion therapy program. PMID- 9369626 TI - A randomized study comparing IV 3000 (transparent polyurethane dressing) to a dry gauze dressing for peripheral intravenous catheter sites. AB - Patients with an intravenous catheter on a cardiology unit were prospectively randomized to receive a transparent polyurethane dressing (N = 49) or sterile gauze (N = 31) dressing to compare security of fixation, dressing condition, skin condition, and rates of inflammation. The mean age of patients was 63 years of age (standard deviation, 12.57), and the average length of cannulation was 18 hours. The only significant difference between the two groups was the dressing condition in the transparent group was significantly better (P = 0.006) than that of the gauze group. The results suggest that gauze dressing may be a viable option to cover i.v. exit sites for patients requiring short-term cannulation. PMID- 9369629 TI - Should you volunteer? PMID- 9369628 TI - Improving the outlook for diagnosing visual disorders: genes on the move! PMID- 9369630 TI - An approach to acquired visual loss in adults. AB - This article has covered the fundamentals of evaluating visual loss. These include a careful history and attention to the "vital signs" of neuro ophthalmology: visual acuities, visual field results, and pupillary reactions. PMID- 9369631 TI - The use of photoscreening to identify visual problems in the preschool population. PMID- 9369632 TI - Adult vision screening by nonphysicians. PMID- 9369633 TI - Consumer product-related eye injuries. PMID- 9369634 TI - Preventing the spread of infection in the contact lens room. PMID- 9369635 TI - Quiz. Syringoma. PMID- 9369636 TI - Helping the victims and the bullies. PMID- 9369637 TI - The innocent heart murmur in children. AB - Most children have an audible murmur at some point from infancy through adolescence. Fortunately most of these murmurs are innocent. These murmurs are asymptomatic and require no follow-up care. On the other hand, pathologic murmurs are symptomatic and do require assessment by a pediatric cardiologist. Referrals are not only anxiety-provoking for the family but are also costly. The pediatric nurse practitioner must therefore be able to differentiate between the innocent and pathologic murmur. Auscultation of heart sounds is the most effective method used to assess murmurs. Given that innocent murmurs are asymptomatic, they require minimal follow-up care, and the expected outcome for a child with the diagnosis of such a murmur is excellent. PMID- 9369638 TI - Making sense of the beta-agonist debate: a guide for nurse practitioners. AB - This article discusses the controversy surrounding the role of beta-agonist use in asthma therapy. Historic issues that led to the controversy are initially reviewed. Current research regarding beta-agonist use is examined, and a discussion on recommendations for patient care is provided. PMID- 9369640 TI - Hyperthyroidism (Graves' disease). PMID- 9369641 TI - Drugs in breast milk: a scientific explanation. PMID- 9369639 TI - Incorporating violence prevention into anticipatory guidance for well child visits. PMID- 9369642 TI - Conjunctivitis: a practice guideline. PMID- 9369643 TI - Munchausen syndrome by proxy. PMID- 9369644 TI - Lifetime benefit caps: "it could happen to you". PMID- 9369645 TI - The first pelvic examination. PMID- 9369646 TI - So you want to change jobs. PMID- 9369647 TI - Nasal spray flu vaccine proves effective in children. PMID- 9369649 TI - Charting with tact. PMID- 9369648 TI - Profile of a NAPNES member. PMID- 9369650 TI - The art of giving encouragement. PMID- 9369651 TI - The NAPNES Pharmacology Certificate. PMID- 9369652 TI - CE--"math for nurses" #93. PMID- 9369653 TI - Antidiabetic agents. PMID- 9369654 TI - Generic nursing outcome objectives for use in long-term care facilities. AB - Twenty-two registered nurses employed in four long-term care facilities generated data for a study about nursing diagnoses in long-term care (N = 360). Generic outcome objectives were developed as an integral part of the project. The research team also specified exceptions to the outcomes: instances where meeting outcome objectives might not be possible. The outcome objectives and exceptions for the sample's 20 most frequently occurring nursing diagnoses are presented as working statements. The authors expect that these outcome objectives and exceptions will be revised by nurses who use them in practice, basic and continuing education, and research. PMID- 9369655 TI - A review of nursing research on the use of unlicensed assistive personnel (UAP). AB - The increased use of unlicensed assistive personnel (UAP) has raised the question: "What nursing research has been conducted to evaluate the effectiveness of the UAP in relation to patient outcomes?" To answer this question, the New York State Nurses Association Council on Nursing Research conducted a literature review on the issue of UAP. The specific purposes of this article are to: (a) present an overview of the health care climate and consumer and RN reaction in relation to the UAP movement, (b) summarize reported reviews of UAP research conducted between 1988 and 1994, (c) critique and synthesize the most recent UAP nursing research conducted between 1994 and 1997, and (d) make recommendations for education, practice, and research. PMID- 9369656 TI - Historical research in nursing: standards for research and evaluation. AB - Historical research, a method of inquiry that combines science and literature, often supports a common thesis that an informed understanding of nursing history provides insights that can contribute effective approaches to current professional issues. Historical research was formally recognized by the American Nurses Association (ANA) in 1965. A review of 11 recent historical research studies supports the concept that adherence to established standards of research and presentation contributes to the value of historical research. While relating an interesting story is an intrinsic element of historical research, the research gains purpose and meaning when the presentation of data includes a statement of purpose utilizing a research question, a review of literature establishing a relation to the greater nursing community, and a concluding analysis relating the research to current and future professional issues. PMID- 9369657 TI - Nursing research activities in New York state are alive and well: a survey of selected acute care facilities and schools of nursing. AB - This survey was conducted to assess the nature and extent of nursing research activities in acute care facilities and schools of nursing in New York state. A questionnaire was mailed to 269 acute care facilities and 42 schools of nursing with a response rate of 29%. Sixty-seven percent of acute facilities and 100% of schools responding reported participating in nursing research activities. Sixty eight percent of the acute care facilities and 67% of the schools of nursing that participated in research activities reported that nursing research was included in staff job descriptions. The findings revealed that the organizational environment in schools was more supportive of research activities than in acute care facilities. Despite changes in health care, including overall downsizing and deletion of nursing research positions, acute care facilities and schools of nursing reported an increase in quality and quantity of research from 1992-1996 compared to 1988-1991. PMID- 9369658 TI - How has caring made a difference for one of your patients? PMID- 9369659 TI - Transcultural nursing care of the elderly is a worldwide imperative. PMID- 9369660 TI - Culture care of Iranian immigrants in New South Wales, Australia: sharing transcultural nursing knowledge. AB - Discovery and analysis of care meanings, expressions, and practices of Iranian Immigrants in New South Wales, Australia was the focus of this ethnonursing qualitative research. The purpose of the study was to systematically discover, describe and analyse the values, beliefs, and practices of Iranian immigrants in New South Wales, Australia. The aim of the investigation was to discover transcultural nursing knowledge to guide nurses and health professionals to provide culturally congruent nursing and health care to Iranians. Leininger's theory of Culture Care Diversity and Universality (Leininger, 1991) was used as the conceptual framework for the study. It was predicted that care meanings and expressions of Iranian immigrants would be influenced by their worldview, social structure features, language, and cultural values rooted in their long ethnohistorical past and reflected in their lifeways in Australia. Using the ethnonursing qualitative research method, key and general informants were purposefully selected among Iranian immigrants residing in New South Wales. Three care themes supported by a number of universal and some diverse patterns were identified for Iranian immigrants. The three themes were: (1) Care meant family and kinship ties (hambastegie) as expressed in daily lifeways and interactions with family, friends, and community; (2) Care as expressed in carrying out traditional urban gender roles (role-zan-o-mard) (Azadie zan) as well as in fulfilling emerging new role responsibilities related to equality for female Iranian immigrants; and (3) Care as preservation of Iranian identity (inhamoni, hamonandi) as expressed in traditional cultural events and health care practices. Leininger's (1991) three modes of actions and decisions were used to develop appropriate and culturally meaningful nursing care actions and decisions which were in harmony with the cultural beliefs of Iranian immigrants. PMID- 9369661 TI - Cultural discovery: an innovative philosophy for creative learning activities. AB - The purpose of this article is to describe a philosophical approach for integrating general transcultural nursing concepts and skills within a first semester associate degree nursing course. The authors wished to design a learning activity that would provide meaningful experiences and stimulate critical thinking among nontraditional, culturally diverse students who must learn to care for many clients of diverse cultural backgrounds. With a focus on culture, aging, and health, this creative learner-centered approach, called Cultural Discovery, emphasizes learning outcomes in both the cognitive and affective domains. Cultural Discovery includes several components in conjunction with the Leininger Acculturation Health Care Assessment Enabler for Cultural patterns in Traditional and Nontraditional Lifeways, specifically: background reading assignments, classroom activity component, collaborative library introductory program, videotape program, interview, literature review, reflection, and written paper assignment. Implemented over an eight week period, Cultural Discovery assisted beginning nursing students to systematically conduct a basic general cultural assessment, identify some similarities and differences among individuals within cultural groups, distinguish between varying dimensions of acculturation, and discover the importance of culturally congruent nursing care. PMID- 9369662 TI - Increasing transcultural awareness: the McMaster-Aga Khan-CIDA Project workshop model. AB - McMaster-Aga Khan-CIDA Project personnel at McMaster University School of Nursing over a period of four years designed and conducted eight one-day introductory workshops for nurses, faculty, staff, host families, and others involved with Pakistani nurses and Lady Health Visitors studying in Canada. The workshops (entitled Increasing Intercultural Awareness) assisted the Canadian and international participants to improve their awareness and knowledge of transcultural communication in preparation for working and socializing together. Using a participatory and active-learning approach, the workshop method introduced participants to transcultural communication; emphasized appreciation of cultural values, similarities and differences; and provided country-specific information on Pakistan. This article outlines the workshop design and rationale and describes specific examples of the transcultural nursing principles, practices, and teaching activities included in the one-day event. PMID- 9369663 TI - Overview of the theory of culture care with the ethnonursing research method. PMID- 9369664 TI - Transcultural nursing: a scientific and humanistic care discipline. PMID- 9369665 TI - Nursing in the People's Republic of China. AB - In June, 1994 Dr. Grayce Roessler led a group of nurses to China to attend and present at international nursing conferences in Beijing and Shanghai. Dr. Roessler, an internationally known transcultural nursing leader, has traveled extensively in China (some 36 trips over 20 years). Her first trip to China, focused on nursing, took place in the fall of 1981 as a member of the American Nurses Association (ANA). The ANA group was invited to China by the Chinese government and the Chinese Nurses Association (CNA). Subsequent to that visit, she became involved in working with the Chinese Ministry of Health, the Chinese Nurses Association, and several of the CNAs in various cities throughout China. In an effort to assist in the preparation of Chinese nurses as teachers and administrators in the evolving health care system, Dr. Roessler facilitated a one year (1985-86) study program in the United States (Golden West College, Huntington Beach, California) for a group of 20 Chinese nurses. It was the first time in history that a number of Chinese nurses had studied at one institution with American nurses in the United States. Dr. Roessler has since coordinated several international conferences in China and arranged for American nurse experts in various fields to present at these meetings. In addition, she has traveled independently as a teacher and consultant and has taken numerous nursing study tour groups to many countries as part of continuing educational experiences. In this issue of the Journal of Transcultural Nursing, Dr. Roessler presents her reflections on nursing in China from a historical and transcultural nursing leader's perspective. PMID- 9369666 TI - Transcultural nursing clinical incident: what do you think? What would you do? Clinical incident #12. PMID- 9369667 TI - Surviving workplace trauma. PMID- 9369668 TI - An old survivor. PMID- 9369669 TI - Surviving Port Arthur. PMID- 9369670 TI - Nursing stress: applying the wisdom of the wounded-healer. AB - We think of stress as a modern problem, however from ancient times and in many cultures it has been recognised that being a healer involves demands, difficulties, vulnerabilities, hurt and pain--that is, healing involves wounding. As nurses engage in healing we experience the stresses inherent in personal and professional life. These may have beneficial effects for stress and can provide challenge and motivation. However when the demands become too much or the source of stress is undesirable, then we become distressed or wounded. PMID- 9369671 TI - Cultural awareness and cultural vision. The First National Forum of Aboriginal and Torres Strait Islander Nurses. AB - Thirty-five Aboriginal and Torres Strait Islander nurses from across Australia met for three days of discussion, including the development of strategies to increase the number of indigenous people in the nursing profession. Indigenous nurses shared their stories, experiences and their specific needs as Aboriginals and Torres Strait Islanders. PMID- 9369672 TI - Changes to the law pertaining to workplace rehabilitation. PMID- 9369673 TI - Patients help with manual handling. AB - Moruya Hospital on the NSW south coast has been taking its health and safety programs to the community in order to improve the public's understanding of safe practices and manual handling equipment use, and to enlist their co-operation. International Nurses' Day was used as an opportunity to meet with the community to promote health and safety. PMID- 9369675 TI - Japanese superunion comes to conference. PMID- 9369674 TI - Victorian nurses under Kennett--battered but not beaten. PMID- 9369676 TI - Nurse in profile. PMID- 9369677 TI - Heroin: nurses address the issues. PMID- 9369678 TI - Anorexia nervosa. Complex illness, complex adolescent nursing. AB - Adolescents requiring inpatient care for anorexia nervosa present an exciting challenge for nurses because of the complex biopsychosocial nature of the illness. Nurses currently play a major role in caring, not only for the physical health of these patients, but for many of their psychological, social and family needs as well. With the strong foundation in holistic care which underpins nursing, scientific research and innovative nursing interventions may well hold the key to improving the current less-than-ideal long-term outcome for young people with anorexia nervosa. PMID- 9369679 TI - "Been there, done that." CanTeen supports teenagers facing cancer. PMID- 9369680 TI - From student nurse to health professional. Interview by Kate Adams. PMID- 9369682 TI - Why I am a union member. PMID- 9369681 TI - Procedural fairness in the disciplinary process. PMID- 9369683 TI - More on exercise and its role in injury prevention. PMID- 9369684 TI - Nurses win CNC dispute. PMID- 9369685 TI - Nurse education in Australia. PMID- 9369686 TI - Enrolled nurses access Bachelor of Nursing programs. PMID- 9369688 TI - International medical retrievals: what you need to know. PMID- 9369687 TI - Managing asthma: An adolescent good news story. AB - In any 12 month period up to 20 per cent of the population will have symptoms of asthma. For some these will be mild and occasional, for others it will be a daily problem requiring medical intervention and even hospitalisation. More than 30 per cent of Australian children have been affected by asthma by the time they reach eight years of age. By the time they are aged 12 this may have risen to over 45 per cent. PMID- 9369689 TI - Nurse in profile. PMID- 9369690 TI - Recognizing congestive heart failure in the neonatal period. AB - Signs of congestive heart failure can be subtle and vary in the time frame of presentation. As a result, this diagnosis is often missed in its early stages. This article reviews risk factors for myocardial dysfunction in the newborn period. Additionally, there is a comprehensive overview of cardiac physiology as it relates to the presentation of symptoms of congestive heart failure. This information is presented to provide a foundation of knowledge related to physiologic changes involved in congestive heart failure so that the health care provider can recognize congestive heart failure early. PMID- 9369691 TI - Cisapride: a review of the evidence supporting its use in premature infants with feeding intolerance. AB - A systematic computerized search of all databases was performed to review the scientific evidence in support of the efficacy of cisapride in reducing feeding intolerance in premature infants. Reference lists from these articles were used to identify relevant scientific literature to address important aspects of the use of cisapride. Three open prospective, uncontrolled studies were found. All studies reported improved clinical outcomes as evidenced by decreased gastric residuals, decreased incidence of vomiting, increased feeding volume, decrease in all reflux parameters measured, and increased weight gain. These observational studies reflect the current state of knowledge and have important research and clinical implications because of the profound effects of feeding intolerance on infant growth and development and on length of stay within NICUs. PMID- 9369692 TI - Now I lay me down to sleep: SIDS and infant sleep positions. AB - Sudden infant death syndrome (SIDS) is the primary cause of infant death outside the neonatal period. The etiology of SIDS has been studied extensively but remains unclear. In 1992, the American Academy of Pediatrics (AAP) responded to international research that suggested an association between SIDS and prone sleeping patterns. Controversial guidelines on infant sleep position were issued at this time, advocating supine or sidelying positions. The AAP modified their initial guidelines in 1996, recommending supine as the preferred sleep position during infancy. The AAP stressed that both sidelying and supine positions place an infant at less risk for SIDS than the prone position, but that supine offered the lowest risk of SIDS. The AAP reaffirmed that these guidelines were intended for healthy newborns only, and also modified some of the original recommendations to reflect the latest research on SIDS. This article provides a brief overview of SIDS and the events leading to the current AAP stance on infant positioning. Parent education is addressed, with specific recommendations for discharge teaching. PMID- 9369694 TI - Behavioral state activity during nipple feedings for preterm infants. PMID- 9369693 TI - Neonatal integrated home care: nursing without walls. AB - A Neonatal Integrated Home Care Program was developed to cross-train NICU staff nurses to provide follow-up care for high-risk neonates in the home. Implementation required collaboration of the NICU and the Center for Home Care and Hospice. Initial target populations were premature infants in transition to oral feeds and oxygen-dependent neonates. Staff, parent, and insurer enthusiasm for this innovative program resulted in expansion to serve infants and families with many other care needs. Continuity of care provides an invaluable resource for families at home with their high-risk infants. Outcomes include reduction in NICU length of stay and readmission for this population. The NICU home care team shares experiences with staff, increasing awareness of and sensitivity to family strengths and discharge realities. The program has fostered revisions in practice regarding preparation for discharge and education of families, facilitating the transition to home following NICU hospitalization. PMID- 9369695 TI - Maternal varicella infection: risks to the mother and baby? PMID- 9369696 TI - Impressions from a public health group visit to China. AB - During my trip to China, I saw how many factors interact to influence maternal and child health. These factors cover a broad scope of biologic, behavioral, environmental, and socioeconomic issues. The experience proved to be invaluable. It has helped me to understand how these factors differ--and how they are alike- in China, Canada, and other cultures. PMID- 9369697 TI - DIC screening in the newborn. AB - Although reliable hemostasis screening in the newborn is difficult to obtain, the information gained from such testing is essential in differentiating the inherited from the acquired bleeding disorder. Sick infants are at risk for developing hemorrhage or thrombosis in response to a variety of diseases or injuries. Screening tests must be interpreted using appropriate normal ranges for term or preterm infants. Neonates are particularly susceptible to DIC because of their underdeveloped reticuloendothelial system and their tendency to develop acidosis, hypothermia, hypoxia, and shock. Bleeding is commonly the results of intravascular coagulation or decreased synthesis of clotting factors by the liver. Criteria based on clinical and laboratory findings have been determined in adults; however, these criteria are not necessarily applicable to neonates. A study reviewing 74 cases of newborns with suspected DIC reported that the most reliable diagnostic tests are the platelet count, D-dimer or FDP, PT, PTT, and fibrinogen. Whatever the test, the nurse's accurate assessment of the neonate, careful collection of blood, and reporting of abnormal results remain paramount in obtaining timely, appropriate care. PMID- 9369698 TI - Basic principles of developmental caregiving. AB - Providing a developmental care approach does not mean you must have all the latest positioning aids and the best technology for reducing light and noise in your nursery. Providing a developmental care approach means realizing that you are going to communicate with the baby and that the baby will communicate with you as you care for him. As you observe the baby and watch what he tells you, you can adjust your care to those messages. You will feel different about your care, and you will be enriched beyond your expectations. PMID- 9369699 TI - Dissolution of tradition: a reprise. AB - Last summer, within the pages of this journal, an essay described the uncertainty surrounding the future of our small but independent VNA ("Dissolution of Tradition into Fantasy: A Lament," May/June, 1996). Supposedly, harsh financial pressures bombarded us and our Board began an inexorable movement toward affiliation with a powerful local hospital. When professional staff became jittery, Board representatives soothed us. This anxious period, given the decidedly unromantic coinage "due diligence," was likened to a courtship phase, an arranged engagement of sorts. Cold feet, second thoughts, panic attacks, and troubled dreams--all were to be expected, considered perfectly natural. All would be forgotten in the bliss of connubial union. Be patient and trust, we were advised; the consummation would make it all worthwhile. And we tried. What has transpired between last summer and this spring, however, exceeded our most vivid nightmare. Betrayed and angry, we scrambled to save what we could of our VNA before it was consigned to obsolescence in this, the year of our centennial. PMID- 9369700 TI - Let me tell you about bedpans. AB - You see, it worked. This title grabbed your attention just like Suzanne Gordon said it would. Suzanne Gordon is a journalist, not a nurse, so she ought to know something about grabbing a reader's attention. As it happens, she also knows something about nursing. If you want to be convinced, read her widely praised new book Life Support--Three Nurses on the Front Lines (Little, Brown 1997). So how does it happen that she is able to write and speak with authority about nursing? Because nurses talked with her about what they do, how they do it, and why. And now she talks back to nurses. Tells us that our passion and anger are all that stand between us and the death of care giving. Challenging things like that. PMID- 9369701 TI - Painful stimulus: absorbing and assimilating grief and loss in HIV nursing practice. AB - To explore grief and loss in nursing care, it is not enough to touch upon it as an occupational hazard to be dealt with. It is also necessary to touch upon our feelings. Internal emotions motivate our external reactions and motivations. They also teach us and guide us. Our reactions, both short-term and long-term, may be both positive and negative. In either case, we need to understand these feelings in order to continue in a positive way within our personal and professional lives. PMID- 9369702 TI - When cultures collide: decision making in a multicultural environment. PMID- 9369703 TI - From motivation to action: understanding nurses' political involvement. AB - Nurses comprise the largest group of health care provides in the nation, but few are in positions to definitively influence public health policy. If the nursing profession is to meet the challenges of the 21st century, political action is necessary, and an understanding of the factors that motivate or impede political action is needed. PMID- 9369704 TI - Through the looking glass: the labor market for registered nurses in the 21st century. AB - From the 1950s through the early 1990s, nurses enjoyed employment security. Now supply outstrips demand and nursing student enrollments are declining. What are the forces at work and how can the rules of the marketplace be used to predict the future? PMID- 9369705 TI - Mary. PMID- 9369707 TI - A holistic approach to health care. PMID- 9369706 TI - AIDS for all by 2000 AD? PMID- 9369708 TI - Nursing assessment of LBW infants. PMID- 9369709 TI - I wish I'd live. PMID- 9369710 TI - Mahatma Gandhi on organizational redesign. PMID- 9369711 TI - To the members of the nursing community. PMID- 9369712 TI - Error-proof the system... PMID- 9369713 TI - Common questions about JCAHO standards. AB - This column is dedicated to answering a variety of the most commonly asked questions regarding JCAHO requirements for accreditation. The subjects range from performance reviews to staffing ratios to counting drugs--and more. PMID- 9369714 TI - Labor law update--Part 5. PMID- 9369715 TI - Technology assessment--who is getting stuck, anyway? AB - Some 13% to 62% of all injuries reported to hospital occupational health workers are traceable to phlebotomy procedures. However, the selection of a needleless system is complex. The informed manager seeks answers to the following questions: (1) Do needleless systems reduce the risk of seroconversion to bloodborne pathogens? (Answer yes.) (2) Does the use of a needleless system affect patients' risk of catheter sepsis? (Answer no.) and (3) What about chemical compatibility with the newer materials used in needleless systems? (New variables require more studies.) The author lists references, manufacturers and some of the chemicals to which some manufacturers have exposed their devices. PMID- 9369716 TI - Technology: nursing the system. Technology and the potential for entrepreneurship. AB - Many nurses are stepping beyond the boundaries of traditional practice and creating their own business or service centers. New entrepreneurial opportunities include working on computer-based patient records, providing consulting services, developing policies and more. Getting involved--joining informatics groups, taking classes--is the first step. PMID- 9369717 TI - Managing risks in subacute care. AB - Risk management should improve the quality of care and clinical outcomes as well as prevent litigation. A systematic risk-management program needs objectives, goals, benchmarks and a continuous quality improvement approach. Three basic tenets help: quality, evaluation and utilization management. PMID- 9369718 TI - How purchasers evaluate health plans. AB - Single health care purchasers and purchasing coalitions are using price, quality and access indicators to help evaluate health plans and foster competition among them. Purchasers also are providing employees with financial reasons to be cost conscious in choosing a health plan and utilizing health services. And they are dispensing information to combat employees' negative perception of managed care. PMID- 9369719 TI - A 4-year history of work redesign in two ICUs. AB - To understand caregiver activities and their associated costs, two intensive care units (ICUs) initiated a work redesign study. During 1 week each year, ICU employees recorded and summarized their activities in 5-minute blocks of time. Activities were analyzed; processes were evaluated and redesigned. PMID- 9369720 TI - Managing an increasingly complex system. AB - A study of more than 170,000 health care workers (including 47,692 registered nurses [RNs]) in 138 acute care health care organizations revealed that the role of the RN is characterized by excessive numbers of activities, a loss of focus on the professional components of nursing and significant activity overlap with other job classes. Additionally, the study found that these characteristics were related to reduced morale, decreased patient and physician satisfaction with care and increased health care costs. The results of this study suggest a need for nursing leaders to develop new methods for controlling the complexity of health care systems, particularly the complexity of the RN role. Controlling complexity requires better tools for identifying system inefficiencies, more advanced skills in cross-functional work process diagnostics and more effective strategies for reducing complexity across health care systems. PMID- 9369721 TI - Pediatric case management in the emergency department. AB - Through coordination of care, pediatric nursing case management improves children's health services and decreases duplication of services and the misuse of the emergency department (ED). This study looks at the effect of pediatric nursing case management on the number of ED visits of chronically ill children before, during and after case management. PMID- 9369722 TI - The Patient Self-Determination Act--measuring its outcomes. AB - Seven years have passed since the Patient Self-Determination Act was implemented. It's time to evaluate its outcomes. A shared governance council collects the data and reports the results. PMID- 9369723 TI - Five pitfalls of work redesign in acute care. AB - During work redesign in nursing units, five common pitfalls can emerge: moving too fast, failing to involve major stakeholders, discounting bargaining unit contracts, separating training classes and not defining desired outcomes. Suggestions on how to avoid these problems are given. PMID- 9369724 TI - Systems redesign in rehabilitation. AB - A performance improvement team overhauled its facility's rehabilitation systems. A rehabilitation care plan was revised and an integrated assessment reduced 29 pages of documentation to 17 pages. Case management goals and documentation are integrated into one care plan. PMID- 9369725 TI - An orientation process for new nurse managers. AB - A management orientation process can provide the means to understand the organization and to build relationships. A thorough understanding of the corporate operations and the matrix to engage in those operations, maps out a successful pathway for the new manager. PMID- 9369726 TI - Working with Peace Corps volunteers. PMID- 9369727 TI - Documentation system changes. PMID- 9369728 TI - Pain and placebos: ethical and professional issues. PMID- 9369729 TI - A study of discomfort and confusion among elderly surgical patients. PMID- 9369730 TI - Pediatric lap belt injuries: care and prevention. AB - Motor vehicle collisions are the leading cause of death from injury during childhood. As children outgrow their toddler car seats, they are often restrained by two-point lap belts, which are fashioned for adult body proportions. Those children restrained by two-point lap belts are at risk for intraabdominal and spinal injury during an auto collision. This article explores the mechanisms of injury and identification of "lap belt syndrome." Aspects of nursing care and prevention strategies will be discussed. A case study illustrates and summarizes the cogent aspects of lap belt related injury and child/family care. PMID- 9369731 TI - Proximal femoral focal deficiency. AB - Proximal femoral focal deficiency (PFFD) is an uncommon congenital defect that involves the femur and acetabulum in varying degrees. It may occur with or without fibular hemimelia and can be unilateral or bilateral in presentation. Children with PFFD and their families are faced with many treatment decisions, both nonsurgical and surgical. Nursing care is central in the care of these children and their families both for psychosocial support and teaching during the decision-making process and for being a patient advocate to help meet postoperative and rehabilitation goals. PMID- 9369733 TI - Promoting positive outcomes from patient complaints. AB - Complaints from patients often indicate their difficulty in coping with the health care system. Nurses need to acknowledge these complaints and help the patient resolve the problem. They need to see complaints as part of a continuous dialogue with their patients and their families. In addition, nurses need to use these complaints to assess the needs of the patient and to evaluate the care and delivery of services. This article presents nine steps the nurse can take when a patient or family member has a complaint. PMID- 9369732 TI - What if you don't get well after an accident. AB - The author shares her experience three years following a life-threatening accident. Many individuals must learn to live with long-term disability. Maximizing assets can facilitate optimal quality of life in spite of limitations. PMID- 9369734 TI - Comparing the effectiveness of different educational programs for patients with total knee arthroplasty. AB - PURPOSE: To compare the effects of preadmission and postadmission educational programs for patients with total knee arthroplasty. DESIGN: Quasiexperimental study. SAMPLE: 60 total knee arthroplasty patients. METHODS: Subjects in the experimental group received preadmission preoperative teaching with an instruction booklet during a preoperative outpatient clinic visit. Upon admission to the hospital, they were presented with an educational video tape. The control group received only postadmission preoperative teaching with the same instruction booklet and no video. PREADMISSION AND POSTADMISSION: Preoperative anxiety level, knowledge about postoperative care, exercise performance and postoperative recovery were used as outcome measures. FINDINGS: The research results found: 1. there was no significant difference between the two groups in reduction of preoperative anxiety score: 2. the experimental group had a significantly higher knowledge level than the control group; 3. the experimental group performed exercise more regularly and correctly than those in the control group; 4. the experimental group had greater flexion of the operative knee joint than the control group. CONCLUSION: Preadmission teaching with a videotape program and a health manual for patients with total knee arthroplasty is recommended. IMPLICATIONS FOR NURSING RESEARCH: More indicators such as postoperative pain and patient satisfaction can be used to investigate the effectiveness of intervention. In addition, increasing the sample size is recommended for future studies. PMID- 9369735 TI - Prophylaxis for thromboembolism in elective orthopaedic surgery. AB - Thromboembolism is a major complication for patients undergoing elective hip and knee surgery. It can delay full recovery and increase the cost of treatment. This review article focuses on the pathophysiology, risk factors, and methods of prophylaxis in this select patient group. Emphasis is placed on the role of the nurse in the ongoing assessment of the patient's risk for thromboembolism. PMID- 9369736 TI - Spinal cord injury without radiographic abnormality (SCIWORA). AB - Spinal cord injury without radiographic abnormality (SCIWORA) is associated with self-reducing transient subluxation or distraction of the juvenile spine. It accounts for about 40% of spinal injuries in children under sixteen. Children's anatomical features increase their susceptibility to hyperflexion, hyperextension and distraction mechanisms. Nursing management includes an awareness of two of its greatest dangers: a delay in onset of symptoms and a possible recurrence. If these dangers are identified early, the child's potential for recovery is maximized. PMID- 9369737 TI - Shoulder immobilizers. Shoulder immobilization devices. AB - Currently a myriad of devices are available for immobilization of the injured or postsurgical upper extremity. Some of these devices are straightforward and easily used, but some are more complicated and require more familiarity for their successful application. However, even simple devices have the potential for misapplication and thus prevent their benefit to the patient. This article is the second in a 3-part series. The goals of the series are (1) to present and review several devices on the market used by shoulder surgeons to immobilize the upper extremity, and (2) to discuss proper application and precautions of their use. It is intended that this series will benefit nurses, therapists, and trainers involved in the use of these devices. PMID- 9369738 TI - Rheumatoid arthritis and osteoarthritis: a basic comparison. AB - Osteoarthritis and rheumatoid arthritis are the two major types of arthritis. Osteoarthritis is a degenerative process, whereas rheumatoid arthritis is an inflammatory process. Nurses need to be able to distinguish between the two types to provide patients with appropriate treatments. PMID- 9369739 TI - Orthopaedic home care independent study. PMID- 9369740 TI - Predictors of hospital acquired heel pressure ulcers. AB - The purpose of this study was to evaluate predictors of hospital acquired heel pressure ulcers. A prospective cohort study of hospitalized patients was conducted (N = 291). Subjects were enrolled by one team and followed by another team that was blind to initial assessment information. Initial assessment included demographics, Braden scale, and other variables found in the first study to be statistically significant. Ongoing evaluation involved heel assessment only. Univariate analysis yielded 15 statistically significant variables. Using multivariate logistic regression, subject's with a potential problem on the Braden Friction and Shear item (p = 0.01) and who were more frequently moist on the Braden Moisture item (p = 0.007) were more likely to develop heel ulcers (chi square 30.52, df 3, p = 0.00001). Receiver Operator Characteristic (ROC) curves were plotted for the Braden scale and multiple other scoring systems. ROC curves were virtually identical using all new scoring systems as compared to the original Braden scale. No new scoring system was identified that led to a clinically significant improvement in sensitivity/specificity over the total Braden scale. While not perfect, the Braden scale may currently be the best predictive tool for heel pressure ulcer development. PMID- 9369741 TI - Wound caring is more than wound care: the provider as a partner. AB - We all know about the placebo effect, but what is it? When a patient "thinks" that he/she is being treated effectively they can improve. Patients who receive supportive interaction do better than those who are alone. These concepts suggest that the mind influences the body's response. This article will discuss the issues of the mind-body connection and its implications in patient care. The first part of this article will provide an overview of the landmark scientific information that validates this intricate relationship between the body and the mind. The second part of this article will focus on the professional practice of medicine and how improved interaction with the patient leads to better outcomes. When the provider becomes a partner with the patient, the results become synergistic. The third part of this article is written by a pervious cancer patient whose presence today is a testimonial to the success of the body/mind alliance and the provider-as-partner concept. She will present the patient's side of medical care. PMID- 9369742 TI - The practice of the provider as a partner. PMID- 9369743 TI - The experience of the patient--healing from the inside out: the patient as a healer and the healed. PMID- 9369744 TI - Geometric, shape and area measurement considerations for diabetic neuropathic plantar ulcers. AB - Though neuropathic plantar ulcers are known to be "round-like," systematic quantitative data on their shape and geometric features are not readily available. A sample of 305 ulcers were retrospectively assessed to provide distribution data on quantitative geometric and shape parameters. After tracing the ulcer during the patient's initial visit, the following parameters were determined: surface area (A), maximum length (L), maximum perpendicular width (W), perimeter (p), shape factor (SF), and an ulcer regularity index (URI). SF assesses ulcer "circularity" and URI measures ulcer perimeter "smoothness" in comparison to a fictitious circle with the same contained area. SF and URI values of 1.0 correspond to 100 percent circularity and regularity. These data and the associated distributions, which are derived from a reasonably large random sample, provide a useful quantitative description of plantar ulcer geometry and shape. PMID- 9369745 TI - Variability in skin microvascular vasodilatory responses assessed by laser Doppler imaging. AB - Skin blood perfusion (SBP) responses to pressure loading and other traumatic and noxious stimuli are used to help identify patients at-risk of skin breakdown, evaluate preventive strategies and help clarify patho-physiological mechanisms in pre-ulcerative and ulcerative conditions. Often, laser-Doppler methods are used to compare vasodilatory responses at differing skin sites to evaluate skin parameter changes. Significant variations in skin microvasculature are known to be normally present, even in closely separated skin zones. In this study, spatial variability and temporal responses of SBP were evaluated with a widely used topical vasodilator (methylnicotinate, MN). A mask with nine holes (1.25 cm2 each) was placed on the volar forearm of ten volunteers. SBP was measured with laser-Doppler Imaging (LDI) prior to applying MN (15 ul, 50 mM) to six zones and 5, 10, 15, 20 and 30 minutes afterwards. Inter-zone mean SBP and inter- and intra zone coefficients of variation (CV) were determined at each time. Results show that MN responses, when determined as zone LDI means, reached maximum at 15 minutes with no significant differences in relative responses among treated zones. Inter-zone perfusion CV's (range 0.11-0.13) were about 50 percent of intra zone CV's (p < 0.01). We conclude that LDI perfusion responses can be obtained at different forearm skin sites with reasonable and acceptable levels of spatial variation if zone mean SBP values are used. PMID- 9369746 TI - Carville ... a tour to remember. PMID- 9369747 TI - Update: venous leg ulcer guideline. University of Pennsylvania. PMID- 9369748 TI - Public notice from the Food & Drug Administration's Center for Devices and Radiological Health. PMID- 9369749 TI - Nursing career structures into the future. PMID- 9369750 TI - Nurse in profile. Dawn Underwood. PMID- 9369751 TI - Guide to handling cytotoxic drugs and related waste. PMID- 9369752 TI - Professional practice concerns. AB - When the Union had numerous reports last year of nurses' professional practice being overridden by non-nurses (for instance where nurses work in special schools, doctors' surgeries and boarding schools) we sought advice from the Queensland Nursing Council. As this problem appears to be occurring more frequently again, we publish below for the information of our members the QNC advice provided in June 1996. (While the QNC advice relates specifically to school nurses, the response has relevance for other QNU members.) PMID- 9369753 TI - [The role of the psychiatric nurse--oppressed and oppressor]. AB - This work aims at analysing the role of the psychiatric nurse in assisting the hospitalized mentally ill, viewing that practice not in itself, but as a social and historical one. An empirical research was done in two psychiatric hospitals in two stages: field observations and interviews with nurses. It was checked that the emphasis the role of the psychiatric nurse is not in therapeutic relationship but in administratives activities and that the relationship the members of the nursing team have with the patient is authoritarian and reproduce the authoritarism of the institutions. Thus the precepts of school that says the chief role of the nurse is the therapeutic relationship seem to have an ideological character. That makes us suggest that the teaching-learning relationships must be established on a praxis basis. PMID- 9369754 TI - [Values that guide the decision process in nursing]. AB - The aim of this study is to identify the values raised by a group of nurses from a health care institution, and to understand in which way these values can interfere in nursing management activities. This study was based on Methodological Triangle which envolves both quantitative and qualitative methods. It was held at a philantropic hospital in Sao Jose do Rio Preto with nurses who work in specialized areas with in-patients. The data were collected using a questionnaire in which three situations were presented covering usual incidents to nurses. These situations required important decisions to be made based on personal values. The results showed that for nurses, honesty, self-control and responsibility are inter-related; usually, the nurses demonstrated tolerance, understanding and solidarity. But, many times, nurses are condescending to their subordinates when their professional competence is not required. However, when trying to attain social recognition, nurses are keen and they can punish their subordinates. PMID- 9369755 TI - [The importance of symbolic interactionism in nursing practice]. AB - The nurse should combine, in their daily practice, technical abilities with a profound comprehension of the main object oh their work, the human being. Symbolic Interactionism is an approach which enables the nursery professional to understand patients by the meaning they value their living experiences. The use of qualitative methods in nursery research is essential because it studies the humans beings and their relationship with the environment, allowing the understanding of the living experiences. These kind of approaches should be even more applied in nursery practice as they open new ways for professional knowledge and enrich practical skills. PMID- 9369756 TI - [Situational leadership: a model for application in Brazilian nursing]. AB - Leadership is a very important theme to the management of nursing care provided to the patient. This study aimed at presenting key-concepts of the leadership model developed by Hersey and Blanchard, entitled Situational Leadership. We believe that this model can bring relevant contributions to nurse's leadership skills. PMID- 9369757 TI - [Group process in nursing: possibilities and limits]. AB - This work shows studies and reflections about the utilisation of groups in nursing assistance. As an aim sought to identify, through nurses perspective, aspects about their motivations to work with groups, their source of knowledge and relevant points of their experience with groups. The results demonstrates that nurses recognise the therapeutic value of groups in assistance and provide suitable conditions to its development. However, difficulties to handling groupal situations are limiting elements to develop this activity that reveal the human sentiment meander, indicating that nurse group co-ordinator needs, beyond theoretical establishment, to practice by their self-knowledge to provide an ambient and a interpersonal relationship able to obtain the real significance of this activity. PMID- 9369758 TI - [Nurses' participation in the development of a multidisciplinary team for chronic and terminal patients]. AB - Since long ago the nurse has become more concerned about the delivery of care for patients with chronic and degeneratives diseases. Nevertheless, the accomplishment of this task is not an easy one. Moreover, when the patient reaches the final stage. Usually this patient experiences emotional and physical alteration. The family is deeply involved in this process and generally they seek nurses help because they are the closest ones to the patient and his/her family. When the patient go trough this dramatic acute change in health condition or in face of chronic degenerative or final stage disease is made, the relationship with the family becomes more difficult demanding nursing intervention. The objective of this study is to report the experience of nurse's participation in the implantation and development of multidisciplinary group for treatment of chronical and final stage patients. This group has been working for two years and has had good results. This group has worked treatment schemes for treatment used by all members of multidisciplinary team. From previous experiences, we knew that there is always a discrepancy between the information given by professional and friends and relatives ones. Which could increase fear and anxiety the reassurance given by the health team, a fair distribution of tasks and the information delivery to the patient proved to be successful. PMID- 9369759 TI - [The Delphi technique to validate nursing interventions]. AB - Know-how and science are universal and have been developed very fast, and nurses have realized their roles in this scientific development. Aiming at analyzing the Delphi though a description of its use in the validity of nursing interventions, to the spinal cord injured in rehabilitation, it was possible to get reliable results by means of a flexible technique and above all of appreciating the opinion and skills of each nurse who deals with the spinal cord injured. This Delphi Technique has given opportunity for specialists to show the interventions recommended to this kind of patients, even so, this context had some needed requirements which identify the make--think in nursing. PMID- 9369760 TI - [Married couples' experiences at a human reproduction center]. AB - The present study was intended to understand the feeling demonstrated by married couples seeking a Human Reproduction Center for infertility evaluation. Intending to understand the way Assisted Reproduction is experienced from the couple's perspective, a phenomenological approach was adopted and the directing question was: "How do you feel using the Assisted Reproduction as a treatment?" PMID- 9369761 TI - [Characteristics of intensive care units in Sao Paulo]. AB - This study is the first part in a series of the articles reporting results of a project conducted to analyse the structural resources of ICUs in Sao Paulo city. This article describes the characteristics of those Units, considering the quantity and geographic location, bed number, maintainer entity, type of assistance, type of client, as well the percentage of beds usage and length of stay. Forty three ICUs were analysed and a questionnaire answered by the ICU nurse coordinator was used to collect data. The results showed that the number of ICUs in the hospital varied from 1 to 4, being more frequently those with only one ICU (68.8%). 79.2% of the Units were in private hospitals, located in the central area of the city. ICU beds represented 8.0% of the total hospital beds and there was an average of 10 beds per Unit. There was a predominance of general ICUs (60.5%), destined only for adult patients (51.2%) and for clinical-surgical treatment (95.3%). The percentage of beds usage in majority of ICU was between 80 to 100% and the length of stay was 4,5 days. PMID- 9369762 TI - [The construction of the mother's personhood: theoretical considerations about identity and the maternal role]. AB - This work is a reflection about the construction of the maternal role into the identity of the woman's identity who experiences the maternity process. Therefore, it sought from literature, theoretical frameworks of some authors, outlining parallels and confronts among them and the implications which they bring about, in the care process when we choose or adopt one theoretical references or concepts. PMID- 9369763 TI - [Nursing staff and occupational accidents in a central supply unit]. AB - The aims of this study are to analyse the occupational accidents that affected nursing workers in the central supply unit of the public hospitals that make part of the ERSA-2 in the city of Sao Paulo and also identify the work load performed by these workers. Data were obtained by verifying all accidents registers that were listed in the Worker Health Attending Service of the institutions related above and by interviewing the workers. Sample was divided in two groups. In the Group I are included sixty-one (61) nursing workers that have registered ninety seven (97) occupational accidents and in the Group II, are included forty five (45) nursing workers who have pointed seventy-eight (78) accidents during the interview. Results were evaluated by quantitative analysis and association tests have been applied, in order to verify the possible differences between the groups of workers. Thus, this study has been able of observe that the major part of affected workers are the female nursing attendants aging from twenty (20) to forty (40) years old. The occupational accidents were also analysed by considering the kind, the place and period in which the accidents occurred; the sort of objects and the injuries that caused them; the body region that has been affected in the worker and if the medical leaves has been necessary and how long it has been taken. The work load evaluated are those identified by the workers of the central supply unit as chemical, physical, biologic, mechanical and physiological loads; The psychic loads have not been mentioned. In this study, the occupational accidents occurrence shows relation with the human and the material resources as well as with the environment and also, the suggestions to minimize them have to consider these points. PMID- 9369764 TI - Fitting in at a new job. PMID- 9369765 TI - The way it was--Lalah's stories. PMID- 9369766 TI - The way it was--RN and me. PMID- 9369767 TI - The way it is today. PMID- 9369768 TI - The way it was--nursing school. PMID- 9369769 TI - Regulations for student nurses in 1940. PMID- 9369770 TI - Infusion pump update. PMID- 9369771 TI - The 1997 earnings survey--slow gains, high earnings. PMID- 9369772 TI - Antibiotics. PMID- 9369774 TI - Complementary therapies--therapeutic horseback riding? PMID- 9369773 TI - When low literacy blocks compliance. PMID- 9369775 TI - Malpractice insurance: for your protection. PMID- 9369777 TI - [An ordinary and exemplary pathology]. PMID- 9369776 TI - Don't lose sleep over the night shift. PMID- 9369778 TI - [Burns. A physical, psychological and social disruption]. PMID- 9369779 TI - [Burns. Who, when, how?]. PMID- 9369781 TI - [Integration of nurses into the burn service]. PMID- 9369780 TI - [Nursing care of burns]. PMID- 9369782 TI - [Nurses in the burn unit]. PMID- 9369783 TI - [The patient and the nurse in a world apart at night]. PMID- 9369784 TI - [Nurse anesthetists in a burn service]. PMID- 9369785 TI - [Management and resuscitation of burned patients]. PMID- 9369786 TI - [Burns in the acute phase. Local and surgical treatment]. PMID- 9369787 TI - [Complications of burns. Clinical aspects and treatment]. PMID- 9369788 TI - [Treatment at Roche Posay. Comprehensive management]. PMID- 9369789 TI - [Clinical ethics and nursing practice]. PMID- 9369790 TI - [Nurse aides, nurses. Prospectives...]. PMID- 9369791 TI - [Varicose veins: venous insufficiency and hospital work conditions]. PMID- 9369792 TI - [Macrolide antibiotics]. PMID- 9369793 TI - [Knee joint. Anatomy and biomechanics]. PMID- 9369794 TI - [Knee arthroscopy]. PMID- 9369795 TI - [Arthroscopic reconstruction of the anterior cruciate ligament]. PMID- 9369796 TI - [Knee ligament arthroplasty. Preoperative and postoperative nursing care]. PMID- 9369797 TI - [While waiting for accreditation, let's get certified!]. PMID- 9369798 TI - [Lighting amplification in the operating room. The radiation protection aspect]. PMID- 9369799 TI - [Anesthesia in urology. Transuretheral prostate resection]. PMID- 9369800 TI - Government affairs. PMID- 9369801 TI - Confusing facets of critical thinking. PMID- 9369804 TI - Lesbian health & homophobia. PMID- 9369802 TI - Critical thinking: the path to the future. PMID- 9369803 TI - Nursing, grief, and dying: cultural contexts for a political happening. PMID- 9369805 TI - Tennessee studies of BSN hospital nurses and their enduring interpersonal values. PMID- 9369806 TI - The Balanced Budget Act of 1997. What's in it for nursing? PMID- 9369807 TI - Licensure undergoes reform. PMID- 9369808 TI - Mapping the telehealth maze. PMID- 9369809 TI - Gun safe coalition leader honored. PMID- 9369810 TI - Cervical ultrasonography compared with manual examination as a predictor of preterm delivery. AB - OBJECTIVE: Our purpose was to compare the accuracy of ultrasonographic and manual cervical examinations for the prediction of preterm delivery. STUDY DESIGN: One hundred two singleton pregnancies at high risk for preterm delivery were followed up prospectively from 14 to 30 weeks with both serial cervical ultrasonography measurements and manual examinations of the length of the cervix. The primary outcome studied was preterm (< 35 weeks) delivery. RESULTS: Excluding six induced preterm deliveries, 96 pregnancies were analyzed. The mean cervical length measured by ultrasonography was 20.6 mm in pregnancies delivered preterm (n = 17) and 31.3 mm in pregnancies delivered at term (n = 79) (p = 0.003); the mean cervical lengths measured by manual examination were 16.1 mm and 18.6 mm in the same preterm and term pregnancies, respectively (not significant). The sixteenth- and twentieth-week ultrasonographic cervical lengths predicted preterm delivery most accurately (p < 0.0005). The 25th percentiles of ultrasonographic (25 mm) and manual (16 mm) cervical lengths showed relative risks for preterm delivery of 4.8 (95% confidence interval 2.1 to 11.1, p = 0.0004) and 2.0 (95% confidence interval 0.5 to 4.7, p = 0.1), respectively; sensitivity, specificity, and positive and negative predictive values were 59%, 85%, 45%, 91%, and 41%, 77%, 28%, and 86%, respectively. CONCLUSION: Cervical length measured by ultrasonography is a better predictor of preterm delivery than is cervical length measured by manual examination. Cervical ultrasonography in patients at high risk for preterm birth seems to be most predictive of preterm delivery when it is performed between 14 and 22 weeks' gestation. PMID- 9369811 TI - Collagenolytic enzymes (gelatinases) and their inhibitors in human amniochorionic membrane. AB - OBJECTIVE: This study was designed to investigate the presence of matrix metalloproteinase-2 (gelatinase A), matrix metalloproteinase-9 (gelatinase B), and their natural inhibitors in both cultured amniochorionic membrane and membrane obtained from women with infection-associated preterm labor. STUDY DESIGN: Amniochorionic membranes were collected from women with documented intraamniotic infection and from women not in labor undergoing elective repeat cesarean section with no signs of infection or other complications of pregnancy. Normal membranes were cultured and exposed to endotoxin and peptidoglycan polysaccharide. Messenger ribonucleic acid expression for gelatinase A, gelatinase B, and tissue inhibitors of matrix metalloproteinase types 1 and 2 was studied with use of reverse transcriptase-polymerase chain reaction and localization of messenger ribonucleic acid was accomplished with use of in situ hybridization. Release of gelatinases from the membranes was studied with gelatin zymography. Tissue inhibitors of matrix metalloproteinase peptides were localized with use of immunocytochemistry. RESULTS: The expression of matrix metalloproteinase types 2 and 9 was seen in amniochorionic membranes in culture. Matrix metalloproteinase-2 was seen in membranes from nonlaboring women and in women with intraamniotic infection, whereas matrix metalloproteinase-9 was seen only in membranes from women with intraamniotic infection. The matrix metalloproteinase-9 expression could also be induced by lipopolysaccharide or peptidoglycan polysaccharide stimulation in culture. In situ hybridization localized messenger ribonucleic acid for these matrix metalloproteinases to both amnion and chorion. Zymogram studies showed the activity of matrix metalloproteinase-2 in normal resting membrane and cultured membrane. Matrix metalloproteinase-9 was induced by culture conditions. Tissue inhibitor of matrix metalloproteinase-1 and tissue inhibitor of matrix metalloproteinase-2 messenger ribonucleic acid was seen in normal, infected, and cultured membranes. In situ hybridization data indicated that these messages were mainly produced by chorion, but they were also seen in amnion. Immunohistochemistry demonstrated the presence of tissue inhibitor of matrix metalloproteinase-1 and tissue inhibitor of matrix metalloproteinase-2 peptides in both amnion and chorion and in cells of the reticular layer of the matrix. CONCLUSION: Normal amniochorionic membrane is a source of matrix metalloproteinase-2 and tissue inhibitors of matrix metalloproteinases. Culture conditions and infection induce matrix metalloproteinase-9 expression and release from amniochorion. These findings suggest that these collagenolytic enzymes may play a role in premature rupture of the membranes in infection, which can lead to preterm labor. PMID- 9369812 TI - Successful magnesium sulfate tocolysis: is "weaning" the drug necessary? AB - OBJECTIVE: Magnesium sulfate is the most commonly used tocolytic agent for preterm labor. A common clinical practice is to slowly discontinue the drug (wean) after successful tocolysis. Our objective was to determine the necessity of this practice. STUDY DESIGN: A prospective, randomized clinical trial was performed from June 1993 to July 1996. After successful magnesium sulfate tocolysis, patients with preterm labor were randomized to two groups: stopping the drug abruptly (no weaning) or gradually weaning the drug (approximately 1 gm every 4 hours). Preterm labor was defined as documented cervical change with regular uterine contractions or regular uterine contractions with a cervix of 2 cm and 75% effacement. The primary outcome variable was the necessity to reinstitute magnesium sulfate therapy within 24 hours of discontinuation of successful tocolysis. RESULTS: One hundred forty-one patients completed the study. No patient in the no-wean group required retocolysis within 24 hours of magnesium discontinuation. However, eight patients in the wean group required retocolysis within 24 hours of magnesium discontinuation (p = 0.01). Significantly more patients in the wean group had retocolysis during pregnancy (3 vs 12, p = 0.03). Patients in the wean group were also in the labor and delivery unit longer and, as would be anticipated, received magnesium sulfate significantly longer. No differences in the neonatal outcomes were noted between the two groups. Seventy-seven percent of the patients in the study were delivered prematurely. CONCLUSION: This study demonstrated an increased need for retocolysis in the group weaned from magnesium sulfate. We also found that patients in the wean group had an increased labor and delivery time and a longer administration time of magnesium sulfate. Thus weaning magnesium sulfate increases health care cost. The practice of weaning magnesium sulfate does not appear beneficial. PMID- 9369813 TI - Encapsulated beta-islet cells as a bioartificial pancreas to treat insulin dependent diabetes during pregnancy. AB - OBJECTIVE: Our purpose was to determine the effectiveness of the bioartificial pancreas technique in correcting (1) maternal carbohydrate metabolism and (2) fetal malformation rates in a pregnant diabetic animal model. STUDY DESIGN: Insulin secretion from encapsulated rat islets cultured in the presence of homologous rat prolactin was determined and compared with that of controls. Streptozotocin-induced diabetic Balb/c mice were then transplanted with rat islet cells encapsulated within alginate microbeads and were then bred. Blood glucose determinations were made after transplantation and throughout gestation. Pups were delivered by cesarean section on day 19 of gestation. Outcome parameters from the transplanted study animals were compared with those of nondiabetic controls and untreated diabetic animals. RESULTS: Insulin secretion was increased twofold in encapsulated rat islets exposed to prolactin compared with control values. Throughout gestation maternal weights and blood, glucose levels of transplanted animals were similar to those of nondiabetic controls. A fetal malformation rate of only 1.4% was observed in the pups from transplanted animals. CONCLUSIONS: Transplanted encapsulated islets are capable of normalizing maternal carbohydrate metabolism in a pregnant diabetic animal model. This therapy, if instituted before conception, also appears to eliminate the increase in fetal malformations seen in diabetic pregnancies. PMID- 9369814 TI - The effect of the source of transfused blood on the rate of consumption of transfused red blood cells in pregnancies affected by red blood cell alloimmunization. AB - OBJECTIVE: Our purpose was to compare the rate of consumption of maternally donated red blood cells with the rate of red blood cells from volunteers in fetuses affected by red blood cell alloimmunization. STUDY DESIGN: The rate of hemoglobin decline was calculated in 293 fetal transfusions in 52 pregnancies, in 43 patients affected by red blood cell alloimmunization from 1987 to 1996. Fifty eight transfusions were excluded from analysis. Hemoglobin decline was stratified by gestational age. The rates of consumption were compared with use of unpaired t tests. RESULTS: The rates of hemoglobin decline (in grams per deciliter per day) were 18 to 24 weeks, 0.47 volunteer and 0.38 maternal (p = 0.174); 25 to 28 weeks 0.41 volunteer, 0.34 maternal (p = 0.46); 29 to 32 weeks, 0.35 volunteer, 0.33 maternal; > or = 33 weeks, 0.37 volunteer, 0.25 maternal, p = 0.048). Hemoglobin decline was less for the maternal donation group than for the volunteer donation group throughout gestation, becoming significant only in fetuses at > or = 33 weeks. CONCLUSION: In the red blood cell-alloimmunized fetus, there is less consumption of maternal than of volunteer red blood cells. This difference reaches a statistical significance only in late gestation. PMID- 9369815 TI - Indomethacin modifies the fetal hemodynamic response induced by percutaneous umbilical blood sampling. AB - OBJECTIVE: Percutaneous umbilical blood sampling induces a marked decrease of impedance to flow in the umbilical artery. Because these changes are believed to be the result of the release of prostanoids, we conducted a study to determine whether indomethacin administration before percutaneous umbilical blood sampling affects the hemodynamic response induced by this procedure. STUDY DESIGN: Percutaneous umbilical blood sampling was performed in 20 singleton pregnancies that were treated for 3 days before the procedure with indomethacin (25 mg orally 6 hours apart) as tocolytic agent and in 22 untreated pregnancies. All the procedures were uncomplicated, and sampling of the umbilical vein was confirmed by blood pressure measurement at the time of the procedure. The umbilical artery pulsatility index and the fetal heart rate were measured immediately before and after the procedure. The first and last aliquots of umbilical vein plasma obtained at the beginning and closing of the procedure were assayed for endothelin-1, 6-keto-prostaglandin F1 alpha and thromboxane B2. RESULTS: In untreated pregnancies percutaneous umbilical blood sampling induced a decrease of the umbilical artery pulsatility index (p < 0.0001) and an increase in 6-keto prostaglandin F1 alpha (p < 0.001) and endothelin-1 levels (p = 0.001), whereas no significant changes were present in fetal heart rate and thromboxane B2 levels. In pregnancies treated with indomethacin, 6-keto-prostaglandin F1 alpha, and thromboxane B2, concentrations at the beginning of the procedure were both significantly less (p < 0.0001) than those found in untreated pregnancies. In pregnancies treated with indomethacin percutaneous umbilical blood sampling did not affect umbilical artery pulsatility index, and 6-keto-prostaglandin F1 alpha and thromboxane B2 levels did not vary during the procedure. However, endothelin 1 (p < 0.001) and fetal heart rate (p < 0.0001) increased after the procedure. CONCLUSION: Indomethacin affects the fetal hemodynamic response to percutaneous umbilical blood sampling by inhibiting the release of prostanoids and the fall in umbilical artery pulsatility index. Under this condition the fetus adapts to the procedure by increasing the heart rate. PMID- 9369816 TI - Intrapartum maternal glucose infusion reduces umbilical cord acidemia. AB - OBJECTIVE: Our purpose was to compare the effects of intrapartum 5% glucose in the intravenous fluid on umbilical cord acid-base and glucose status after spontaneous vaginal delivery. STUDY DESIGN: This was a prospective randomized clinical trial in which gravid women with low-risk pregnancies at term were randomized by computer to receive lactated Ringer's solution, either with 5% glucose or without, as the maintenance intravenous fluid during active labor. Antepartum and intrapartum factors that might influence fetal-neonatal glucose levels were recorded. Umbilical arterial cord blood was assessed for glucose level and acid-base status. RESULTS: Of the 106 parturient patients who consented, 15 were excluded because of operative delivery (n = 8), preeclampsia (n = 2), shoulder dystocia (n = 1), intravenous fluid infusion duration of < 1 hour (n = 1), and cord blood data not available (n = 3). There were no statistical differences between the two groups regarding maternal age, parity, maternal weight at term, epidural placement, intravenous fluid duration, or gestational age. Infant birth weight, gender, Apgar scores, and incidence of meconium were not statistically different. Neonatal hypoglycemic episodes and intrapartum fetal heart rate tracing parameters were similar between groups. The difference between the umbilical artery pH values of those who were treated with lactated Ringer's solution with 5% glucose (n = 48) versus those treated with the solution without glucose (n = 43) approached significance, with a p value of 0.08 (mean +/- SD, 7.30 +/- 0.07 and 7.27 +/- 0.09, respectively). The PCO2 value of those treated with lactated Ringer's solution without glucose was higher (mean +/ SD, 50.6 +/- 12.9 mm Hg vs 44.8 +/- 9.9 mm Hg) (p = 0.02). Base excess (in milliequivalents per deciliter) and cord glucose (in milligrams per deciliter) levels, as well as the incidence of neonatal hypoglycemic episodes within the first 8 hours of life, were not statistically different. Despite failure of mean pH differences to achieve significance, the relative risk (0.22) for an umbilical arterial pH < or = 7.20 was significantly reduced (95% confidence interval 0.1 to 0.7) with lactated Ringer's solution containing 5% glucose. The relative risk (0.42) of having an umbilical artery cord blood PCO2 value > or = 55 mm Hg was also significantly lowered (95% confidence interval 0.19 to 0.93) when lactated Ringer's solution containing 5% glucose was used. CONCLUSIONS: Intrapartum intravenous fluid consisting of lactated Ringer's solution containing 5% glucose reduces umbilical cord acidemia and hypercarbia but does not change cord levels of glucose or base excess. Lactated Ringer's solution containing 5% glucose may be a preferable solution than without glucose as an intravenous fluid during labor. PMID- 9369817 TI - Controlled cord traction versus minimal intervention techniques in delivery of the placenta: a randomized controlled trial. AB - OBJECTIVES: Our purpose was to compare the controlled cord traction technique with the minimal intervention technique for delivery of the placenta. The primary outcome was the incidence of postpartum hemorrhage. Secondary outcomes included duration of third stage of labor, frequency of retained placenta, hemorrhagic shock, the need for blood transfusion, and the need for uterotonic agents to control postpartum hemorrhage. STUDY DESIGN: A total of 1648 women who were delivered vaginally were randomly allocated during labor to the controlled cord traction group (n = 827) or the minimal intervention group (n = 821). In the controlled cord traction group women received oxytocin, 10 units intramuscularly, with delivery of the baby's anterior shoulder, after which the placenta was delivered actively by controlled cord traction (Brandt-Andrews method). In the minimal intervention group the placenta was delivered by maternal pushing. Continuous intravenous oxytocin was given after delivery of the placenta. Odds ratios with 95% confidence intervals were calculated for each variable. RESULTS: The overall incidence of postpartum hemorrhage was significantly lower in the controlled cord traction group (5.8% vs 11%; odds ratio 0.50, 95% confidence interval 0.34 to 0.73). The incidence of retained placenta (> or = 30 minutes) was 1.6% in the controlled cord traction group and 4.5% in the minimal intervention group (odds ratio 0.31, 95% confidence interval 0.15 to 0.63). Significantly more patients in the minimal intervention group required additional uterotonic agents to control hemorrhage (5.1% vs 2.3%; odds ratio 0.44, 95% confidence interval 0.24 to 0.78). CONCLUSION: The controlled cord traction technique for delivery of the placenta results in a significantly lower incidence of postpartum hemorrhage and retained placenta, as well as less need for uterotonic agents, compared with the minimal intervention technique. PMID- 9369818 TI - Prediction of umbilical artery base excess by intrapartum fetal oxygen saturation monitoring. AB - OBJECTIVE: Our purpose was to evaluate the predictive value of intrapartum fetal oxygen saturation as monitored by reflectance pulse oximetry (SpO2) for metabolic acidosis at birth. STUDY DESIGN: An observational study was carried out on intrapartum patients at > or = 35 weeks' gestation having either a nonreassuring fetal heart rate pattern, intrauterine growth restriction, or thick meconium. Fetal oxygen saturation monitoring was performed with use of the Nellcor N-400 monitor and the FS-14 fetal oxygen sensor. Mean values of SpO2 from the last 30 minutes of monitoring were correlated with umbilical artery base excess and pH at birth, with use of regression analysis, whereas the prediction of acidosis by SpO2 at different thresholds was tested with use of receiver-operator characteristic curve calculations. RESULTS: Fifty-four patients met the criteria for data analysis, with a mean SpO2 monitoring time of 150 +/- 124 minutes (SD) and a mean signal loss of 30% +/- 20%. Mean fetal SpO2 for the last 30 minutes of monitoring averaged 42.1% +/- 9.9% and, for individual patient studies, correlated significantly with calculated oxygen saturation in the umbilical vein (r = 0.52, p < 0.001) and in the umbilical artery (r = 0.34, p = 0.02) as measured at birth. However, the correlation with umbilical artery base excess values at birth was somewhat weaker (r = 0.30, p < 0.05), as was the correlation with umbilical artery pH values (r = 0.26, p = 0.05). Receiver-operator characteristic curve calculations were all nonsignificant when SpO2 from the last 30 minutes of monitoring was used as a diagnostic test for predicting acidosis at birth. CONCLUSIONS: Intrapartum fetal SpO2 as monitored in the current study was of limited use as a diagnostic test for predicting acidosis at birth, regardless of the SpO2 cutoff value used. PMID- 9369819 TI - Maternal colonization with group B Streptococcus and prelabor rupture of membranes at term: the role of induction of labor. TermPROM Study Group. AB - OBJECTIVES: Our purpose was to determine the effect of induction of labor on neonatal infection if mothers are group B streptococci positive and have prelabor rupture of membranes at term. STUDY DESIGN: In the TermPROM study 5041 women were randomized to induction with intravenous oxytocin, induction with vaginal prostaglandin E2 gel, or expectant management with induction, if needed. Of these, 4834 women had vaginal or introital swabs for group B streptococci taken at entry. We used logistic regression to test for effects of treatment within group B streptococci subgroups. RESULTS: Group B streptococci were predictive of neonatal infection for the induction with vaginal prostaglandin E2 gel and expectant groups but not for the induction with oxytocin group. For women positive for group B streptococci the rates of neonatal infection were 2.5% for the induction with oxytocin group and > 8% for all other groups. CONCLUSIONS: Induction of labor with intravenous oxytocin may be preferable for group B streptococci-positive women with prelabor rupture of membranes at term. PMID- 9369820 TI - A randomized, prospective study comparing once-daily gentamicin versus thrice daily gentamicin in the treatment of puerperal infection. AB - OBJECTIVE: The efficacy, safety, and antibiotic-related charges for once-daily gentamicin with twice-daily clindamycin were compared with those of thrice-daily dosing of these antibiotics. STUDY DESIGN: Patients with puerperal endometritis or with chorioamnionitis in labor assessed to be at risk for endometritis were randomized to receive gentamicin 4 mg/kg intravenously every 24 hours with clindamycin 1200 mg intravenously every 12 hours (experimental arm) or gentamicin 1.33 mg/kg intravenously and clindamycin 800 mg intravenously every 8 hours (conventional dosing interval arm). Primary outcomes included cure rates, mean length of treatment, antibiotic-related charges, and nephrotoxicity. Multiple logistic regression analysis was used to control for confounding variables. RESULTS: There were 135 and 137 patients randomized to the experimental and conventional interval arms, respectively. Cures were obtained in 94.1% and 87.6% of patients in the experimental and conventional arms, respectively (p = 0.06). The experimental arm had mean antibiotic charges of $250.79 versus $442.49 in the conventional arm (p < 0.0001). There was no permanent nephrotoxicity in either group. CONCLUSIONS: Once-daily gentamicin dosing with twice-daily clindamycin dosing is as efficacious and safe as the thrice-daily dosing of gentamicin and clindamycin for peripartum uterine infection. The experimental regimen results in substantial cost savings. The incidence of nephrotoxicity is low. PMID- 9369821 TI - Elevated amniotic fluid nitric oxide metabolites and cyclic guanosine 3',5' monophosphate in pregnant women with intraamniotic infection. AB - OBJECTIVE: Our purpose was to compare amniotic fluid nitric oxide metabolites and cyclic guanosine 3',5'-monophosphate in pregnant women with and without intraamniotic infection. STUDY DESIGN: Amniocentesis was performed on 72 pregnant women with preterm contractions, labor, or rupture of membranes. Fourteen patients had intraamniotic infection and 58 did not. Intraamniotic infection was defined as the presence of a positive amniotic fluid culture. Amniotic fluid Gram stain, glucose, leukocyte counts, leukocyte esterase activity, creatinine, pH, and specific gravity were performed. Endogenous nitrite was determined using Griess reagent. Amniotic fluid nitric oxide metabolites (nitrite and nitrate) were measured after reduction of nitrate to nitrite with Aspergillus nitrate reductase. Tests for amniotic fluid cyclic guanosine monophosphate levels were determined by enzyme immunoassay. Two-tailed t test, contingency table methods, linear regression, and correlation were used for statistical analyses. RESULTS: Amniotic fluid levels of nitric oxide metabolites, endogenous nitrite, nitrate, and cyclic guanosine monophosphate were significantly higher in pregnant women with intraamniotic infection than in those without intraamniotic infection (2.66 +/- 0.49 vs 1.77 +/- 0.07 mumol/mg creatinine, p = 0.002; 0.69 +/- 0.15 vs 0.38 +/- 0.03 mumol/mg creatinine, p = 0.003; 1.99 +/- 0.41 vs 1.38 +/- 0.07 mumol/mg creatinine, p = 0.02; and 1.47 +/- 0.22 vs 0.90 +/- 0.08 nmol/mg creatinine, p = 0.004, respectively). Both amniotic fluid nitric oxide metabolites and cyclic guanosine monophosphate were positively correlated with amniotic fluid leukocyte counts and leukocyte esterase activity and negatively correlated with amniotic fluid glucose concentrations. CONCLUSIONS: Our data indicate that amniotic fluid nitric oxide and cyclic guanosine monophosphate may play important roles in the pathogenesis of intraamniotic infection. Measurements of amniotic fluid nitric oxide metabolites and cyclic guanosine monophosphate may be part of a panel of tests that can be used to detect intraamniotic infection. PMID- 9369822 TI - Experimentally induced intrauterine infection causes fetal brain white matter lesions in rabbits. AB - OBJECTIVE: Periventricular leukomalacia, a common brain white matter lesion in preterm neonates, is a major risk factor for cerebral palsy. Epidemiologic studies have demonstrated an association between infection and periventricular leukomalacia. The purpose of this study was to determine whether ascending intrauterine infection could cause brain white matter lesions in the fetal rabbit. STUDY DESIGN: Rabbits with timed pregnancies underwent hysteroscopy at 20 to 21 days of gestation (70%). Animals were allocated in a ratio of 2:1 for inoculation with either Escherichia coli (0.2 ml containing 10(3) to 10(4) colony forming units) or sterile saline solution. Both groups were treated with ampicillin-sulbactam (Unasyn, 100 mg/kg per day; Pfizer, Seoul) every 8 hours until they were killed 5 to 6 days after hysteroscopy. Histologic examination of the placentas and fetal brains was conducted. RESULTS: Forty-five animals underwent hysteroscopy; 31 were inoculated with E. coli and 14 with sterile saline solution. At the time the animals were killed, the rate of intrauterine infection was higher and there were fewer live fetuses in the E. coli-inoculated animals than in the saline solution group. Histologic evidence of brain white matter damage was identified in 12 fetuses born to 10 E. coli-inoculated rabbits but none in the saline solution group (p < 0.05). All rabbits with brain white matter lesions had evidence of intrauterine infection. Evidence of white matter damage included increased karyorrhexis, rarefaction, and disorganization of white matter. Apoptosis was demonstrated in areas of white matter damage by immunohistochemical studies. CONCLUSION: Experimental ascending intrauterine infection can cause fetal brain white matter lesions. PMID- 9369823 TI - Interleukin-10 and transforming growth factor-beta inhibit amniochorion tumor necrosis factor-alpha production by contrasting mechanisms of action: therapeutic implications in prematurity. AB - OBJECTIVE: This study was designed to detect the regulatory effect of the immunoinhibitory cytokines interleukin-10 and transforming growth factor-beta on the amniochorion production of tumor necrosis factor-alpha. STUDY DESIGN: Amniochorionic membranes were collected from women undergoing elective repeat cesarean section with no history of infection. Membranes were placed in organ explant culture for 48 hours and then stimulated with lipopolysaccharide (50 ng/ml), lipopolysaccharide plus interleukin-10 (50/ 50, 50/100 ng/ml), interleukin-10 (50 and 100 ng/ml), lipopolysaccharide plus transforming growth factor-beta (50/50 and 50/100 ng/ml), and transforming growth factor-beta (50 and 100 ng/ml). At the end of a 24-hour stimulation tissue samples were frozen for ribonucleic acid analysis and media samples were frozen for enzyme-linked immunosorbent assay. Quantitation of the messenger ribonucleic acid was accomplished by quantitative competitive polymerase chain reaction, and tumor necrosis factor-alpha protein was assayed by use of enzyme-linked immunosorbent assay. RESULTS: Lipopolysaccharide stimulation of fetal membranes produced approximately 60,000 molecules of tumor necrosis factor-alpha messenger ribonucleic acid, whereas control tissue produced none. Lipopolysaccharide plus interleukin-10 stimulation resulted in a dose-dependent decrease in tumor necrosis factor-alpha messenger ribonucleic production (transcriptional regulation) to 6000 (50/50) and 600 (50/100) molecules. Enzyme-linked immunosorbent assay performed on media samples from these experiments demonstrated a dose-dependent reduction in tumor necrosis factor-alpha peptide release. Stimulation of membranes with lipopolysaccharide plus transforming growth factor-beta had minimal effects on tumor necrosis factor-alpha messenger ribonucleic acid and protein production compared with lipopolysaccharide-treated samples. Membranes stimulated with interleukin-10 alone showed no effect on messenger ribonucleic acid or protein levels and remained similar to the levels seen in control tissues. In the absence of lipopolysaccharide, transforming growth factor-beta treatment produced a dramatic decrease in tumor necrosis factor-alpha peptide levels without affecting messenger ribonucleic acid levels. CONCLUSION: In the presence of a stimulatory agent, interleukin-10 down-regulates tumor necrosis factor-alpha release from cultured human amniochorionic membranes. Transforming growth factor-beta seems to have some stimulatory effect on transcription, and no effect on translation was seen with concurrent lipopolysaccharide stimulation. However, down-regulation of tumor necrosis factor alpha peptide by transforming growth factor was seen in fetal membranes when not overridden by an inflammatory stimulant. This study suggests that interleukin-10 and transforming growth factor-beta can regulate tumor necrosis factor-alpha release from amniochorion under different conditions and by a different mechanism. PMID- 9369824 TI - A promoter mutation that increases transcription of the tumor necrosis factor alpha gene is not associated with preterm delivery. AB - OBJECTIVE: Increased amniotic fluid concentrations of tumor necrosis factor-alpha are observed in women with preterm labor and subsequent preterm birth. We tested whether a mutation in the promoter region of tumor necrosis factor-alpha gene, TNF T2, which increases transcription of the gene, is more frequent in a preterm delivery cohort. STUDY DESIGN: Deoxyribonucleic acid was extracted from whole blood of 203 women and 44 fetuses delivered at < 37 weeks of estimated gestational age. The polymerase chain reaction was used to amplify the promoter region of the tumor necrosis factor-alpha gene. The resulting polymerase chain product was subjected to allele-specific enzymatic digestion with Nco I. Fragments were size fractionated on a 3% Metaphor agarose gel stained with ethidium bromide. Results were analyzed with use of a chi 2 contingency table. RESULTS: No statistically significant differences for either the TNF T1 or TNF T2 allele frequencies were found between women or fetuses delivered preterm compared with a control group or previously published allele frequencies. CONCLUSIONS: The frequency of this tumor necrosis factor-alpha promoter mutation, TNF T2, is not increased in either women or fetuses delivered at < 37 weeks' gestation. Basal levels of tumor necrosis factor-alpha are unlikely to affect a woman's risk of preterm delivery. Tumor necrosis factor-alpha variants should not be used as a predictive test for preterm delivery. PMID- 9369825 TI - Management options in women with preterm uterine contractions: a randomized clinical trial. AB - OBJECTIVE: Our purpose was to evaluate three management strategies and to assess pregnancy outcomes in women with preterm uterine contractions. STUDY DESIGN: Consenting women seen in our hospital triage area with preterm uterine contractions were randomly assigned to observation alone, intravenous hydration, or one dose of subcutaneous terbutaline sulfate (0.25 mg). Eligible women had a singleton gestation between 20 and 34 weeks, intact membranes, more than three contractions in 30 minutes, and a cervical dilation < or = 1 cm and effacement < 80%. Women who had progressive cervical change at < 34 weeks were treated with intravenous tocolysis. Women with recurrent preterm uterine activity remained in their assigned group during subsequent triage visits. RESULTS: One hundred seventy-nine women were randomized: observation (56), hydration (62), and terbutaline (61). Women in these three groups were similar with respect to maternal age, race, parity, prior preterm births, gestational age at randomization, contraction frequency, and mean cervical dilatation. There were no intergroup differences in the mean days to delivery, the number of repeat triage visits, the incidence of preterm labor at < 34 weeks, or the frequency of preterm deliveries at < 34 weeks and < 37 weeks. Women assigned to terbutaline had contractions stopped and were discharged earlier (terbutaline 4.1 +/- 5.1 hours, observation 5.2 +/- 5.3 hours, hydration 6.0 +/- 5.7 hours; p = 0.006). No complications of therapy were observed. CONCLUSIONS: The use of intravenous hydration in the management of preterm contractions was of no benefit. The use of one dose of subcutaneous terbutaline resulted in the shortest length of triage stay but did not affect pregnancy outcome. PMID- 9369826 TI - Is there justification for using indomethacin in preterm labor? An analysis of neonatal risks and benefits. AB - OBJECTIVE: Recent reports have suggested that the use of indomethacin for tocolysis may independently increase the risk for major adverse neonatal events such as intraventricular hemorrhage and necrotizing enterocolitis. The objective of this study was to determine whether this potential risk of indomethacin is outweighed by the benefit of delivery delay at gestational ages < 32 weeks. STUDY DESIGN: We constructed separate decision trees to compare strategies of tocolysis with indomethacin versus no tocolysis for hypothetic cohorts of patients with idiopathic preterm labor at 24, 26, 28, 30, and 32 weeks' gestation. Probabilities for these decision models, including estimates of indomethacin efficacy and the potential for increase in adverse neonatal events with indomethacin, were obtained from the medical literature. The primary outcome was the number of expected adverse neonatal events per 1000 women for each strategy at each gestational age. RESULTS: In the base case analysis tocolysis with indomethacin was a more favorable strategy than no tocolysis across all gestational ages that we studied. As expected, the difference in the number of events between the two strategies declined with advancing gestational age because of a decreasing baseline risk for adverse neonatal events as gestational age increased. The models at 26, 28, 30, or 32 weeks were not sensitive to our estimates of indomethacin efficacy, nor to our estimates of baseline neonatal morbidity or steroid efficacy, or to the relative increase in some neonatal morbidities with indomethacin use. CONCLUSIONS: On the basis of current estimates, the benefits of indomethacin outweigh the potential risks to the neonate at gestational ages < or = 32 weeks. Thus the use of indomethacin for tocolysis at these ages is a reasonable strategy. PMID- 9369827 TI - Amniotic fluid cytokines (interleukin-6, tumor necrosis factor-alpha, interleukin 1 beta, and interleukin-8) and the risk for the development of bronchopulmonary dysplasia. AB - OBJECTIVE: Our purpose was to test the hypothesis that neonates who develop bronchopulmonary dysplasia have higher amniotic fluid concentrations of proinflammatory cytokines than those who do not develop bronchopulmonary dysplasia. STUDY DESIGN: The relationship between amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 and the occurrence of bronchopulmonary dysplasia in the neonate was examined in 69 patients who were delivered of preterm neonates (< or = 33 weeks) within 5 days of amniocentesis. Cytokines were measured by specific immunoassays. RESULTS: Bronchopulmonary dysplasia was diagnosed in 19% (13/69) of newborns. Median amniotic fluid concentrations of interleukin-6, tumor necrosis factor alpha, interleukin-1 beta, and interleukin-8 concentrations were significantly higher in mothers whose infants had bronchopulmonary dysplasia than in mothers whose infants did not have bronchopulmonary dysplasia (p < 0.05 for each). Neonates who had bronchopulmonary dysplasia were delivered at earlier gestational ages and had lower birth weights than those without bronchopulmonary dysplasia. The differences in median amniotic fluid interleukin-6, interleukin-1 beta, and interleukin-8 between these two groups remained significant after we adjusted for the effect of gestational age at birth (p < 0.05 for each). CONCLUSIONS: (1) Antenatal exposure to proinflammatory cytokines is a risk factor for the development of bronchopulmonary dysplasia; (2) the injury responsible for bronchopulmonary dysplasia in a subset of neonates may begin before birth. PMID- 9369828 TI - Randomized trial of single-dose versus multiple-dose cefotetan for the postpartum treatment of intrapartum chorioamnionitis. AB - OBJECTIVE: Our purpose was to determine whether a single postpartum dose of a cephalosporin would effectively treat women with intrapartum chorioamnionitis and decrease the length of hospitalization. STUDY DESIGN: After vaginal delivery consenting women who had received antibiotics for chorioamnionitis were assigned to postpartum treatment with either a single 2 gm intravenous dose of cefotetan or to cefotetan 2 gm given intravenously every 12 hours for a minimum of 48 hours. Chorioamnionitis was defined as an intrapartum temperature of > or = 100.4 degrees F and maternal or fetal tachycardia, maternal leukocytosis, or uterine tenderness. Patients were discharged when they had received their assigned dosage of cefotetan, were afebrile (temperature < 100.4 degrees F) and > or = 24 hours from delivery. RESULTS: We studied 109 women (55 single dose, 54 multiple dose) with chorioamnionitis. The two groups were similar with regard to demographic and intrapartum characteristics. The median (range) interval from delivery to discharge was 24 hours lower in the single-dose group (33 [16 to 190] vs 57 [36 to 190] hours, p = 0.0001). The incidence of failed therapy was similar (single dose: 6/55, 11%, vs multiple dose: 2/54, 3.7%, p = 0.27). CONCLUSIONS: A single postpartum dose of cefotetan appears to be effective treatment for intrapartum chorioamnionitis after a vaginal delivery and decreases the length of hospital stay. PMID- 9369829 TI - Is fluorescence polarization reliable and cost efficient in a fetal lung maturity cascade? AB - OBJECTIVE: The objective of the study was to compare the accuracy of the TDxFLM test (Abbott Laboratories) with the fetal lung maturity cascade (shake, foam stability index, lecithin/sphingomyelin tests) and to determine whether the TDxFLM test could increase the efficiency and reduce the cost without decreasing the reliability of a cascade. STUDY DESIGN: A prospective, single-blinded study was conducted. Uncontaminated amniotic fluid obtained by transabdominal amniocentesis for fetal lung maturity assessment was evaluated with use of the fetal lung maturity cascade and the TDxFLM test. At study completion the results of the TDxFLM test were compared with those of the maturity cascade with regard to hyaline membrane disease, which was defined by strict clinical and radiographic parameters. A power analysis was performed requiring a sample size of 100 infants delivered within 72 hours of amniocentesis with use of the 95% confidence interval. RESULTS: A total of 115 cases had a full maturity cascade performed, of which 40 (35%) had a positive shake or foam stability index and 75 cases required progression to a lecithin/sphingomyelin ratio because of negative results. The TDxFLM test result was > or = 70 mg/gm in 42 (37%) of these 115. One hundred eight newborns were delivered within 72 hours of the amniocentesis; 65% (71) of these were between 30 and 37 weeks of estimated gestational age. There were 7 cases of hyaline membrane disease in the 108 newborns. Of these 108, 87 had a mature original cascade versus 85 mature tests with use of a proposed TDxFLM test-lecithin/sphingomyelin ratio cascade with one case of respiratory distress syndrome and hyaline membrane disease. The sensitivity, specificity, and positive and negative predictive values for the original cascade were 86%, 84%, 27%, and 99%, respectively; for the proposed TDxFLM test-lecithin/sphingomyelin ratio cascade the values were 86%, 83%, 26%, and 99%, respectively. The TDxFLM test-lecithin/sphingomyelin ratio cascade would have resulted in a cost reduction of 24% with no significant delay in turnaround time. CONCLUSION: The TDxFLM test appears to be a reliable and accurate assessment of fetal lung maturity. Furthermore, by replacing the shake and foam stability index portion of the cascade with the TDxFLM test, a cost savings of 24% would occur without a decrease in safety. These results also reveal that it could enhance patient care and be cost efficient for institutions not currently doing fetal pulmonary maturity testing to undertake use of the TDxFLM test and to only send out specimens for a lecithin/sphingomyelin ratio that have an initial immature TDxFLM test result (< 70 mg/gm). Likewise, institutions currently only performing a lecithin/sphingomyelin ratio may consider a TDxFLM test-lecithin sphingomyelin ratio cascade. Although direct costs would increase, they would be counterbalanced by a significant reduction in laboratory technician time. PMID- 9369830 TI - Measurement of fetal nasal width by ultrasonography. AB - OBJECTIVE: This study was designed to determine the range of normal fetal nasal width by ultrasonography, which may be beneficial for detection of trisomy 21 and other chromosomal abnormalities. We hypothesize that a wide, saddle-shaped nose, which is one of the clinical neonatal anatomic features of trisomy 21, can be diagnosed prenatally. STUDY DESIGN: Fetal nasal width diameter was measured on 782 normal white fetuses by ultrasonography. Gestational ages ranged from 13.8 to 40.4 weeks. Mean and SD of fetal width diameter was calculated weekly by gestational age to establish normal values. RESULTS: The fetal nasal width increased as a function of gestational age, showing a polynomial curve during pregnancy (r = 0.912, p = 0.002). With use of mean +/- 1 SD as a cutoff value, the results showed a sensitivity of 80% with a specificity of 67% and a positive predictive value of 2.2% with a negative predictive value of 99.7% for the diagnosis of trisomy 21. CONCLUSION: The fetal nasal width diameter may be used as a biometric measurement and may be useful to identify trisomy 21 or other chromosomal abnormalities in conjunction with other already defined parameters used in a genetic ultrasonographic screen. PMID- 9369831 TI - Telemedicine and fetal ultrasonography: assessment of technical performance and clinical feasibility. AB - OBJECTIVE: Our aim was to determine the performance and clinical feasibility of telesonography for the interpretation of fetal anatomic scans sent from a remote location compared with those obtained at a tertiary care prenatal ultrasonography center. STUDY DESIGN: Routine ultrasonographic studies from 35 patients were remotely interpreted. Evaluation included a blinded comparison of the sonographer's assessment of 38 fetal structures with that of the physician at the tertiary care center. Technical evaluation included system reliability and the number of digital telephone lines required for adequate real-time visualization. RESULTS: The mean gestational age at the time of the ultrasonography was 25.84 +/ 6.8 weeks (range 14 to 38). There was complete consistency of interpretation for 25 of 38 (66%) fetal structures. Thirteen structures had discrepancies in visualization, reflecting a difference in the adequacy of visualization, not the normalcy or identity of the structures. Three digital (integrated switching digital network, ISDN) telephone lines were required for real-time visualization. CONCLUSION: Our preliminary experience supports telesonography as a clinically useful tool for remote interpretation of fetal ultrasonographic examinations. Further studies are warranted for the continued evaluation of this emerging technology. PMID- 9369832 TI - Outcome of twin gestations with a single anomalous fetus. AB - OBJECTIVE: Our goal was to determine whether the presence of one anomalous fetus in a twin gestation affects pregnancy outcome when compared with twin pregnancies without fetal anomalies. STUDY DESIGN: Maternal and neonatal data from 970 twin pregnancies delivered from 1988 to 1995 were collected. Three groups of twin gestations were identified: one fetus with a major anomaly (n = 18), one fetus with a minor anomaly (n = 38), and both fetuses without anomalies (n = 914). RESULTS: Maternal demographic characteristics (age, race, and antepartum complications) were similar among the groups. There was no difference in neonatal outcome (gestational age at delivery, birth weight, cord pH, sepsis, and death) in the minor anomaly and no anomaly groups. There were significant differences between the major anomaly group and the no anomaly group in gestational age at delivery (32.9 vs 35.6 weeks, p < 0.05), birth weight at delivery (1759 vs 2291 gm, p < 0.05), hospital days (41 vs 13 days, p < 0.05), and perinatal death of the anomalous fetus (278/1000 vs 10/1000). Except for total days in the hospital, there was no difference in neonatal morbidity or mortality for the normal fetus when compared with the minor group or the no anomaly group. CONCLUSION: The presence of a fetus with a major anomaly in a twin gestation increases the risk of preterm delivery. The neonatal outcome of the nonanomalous fetus does not appear to be affected by the anomalous fetus. PMID- 9369833 TI - Interobserver reliability of digital and endovaginal ultrasonographic cervical length measurements. AB - OBJECTIVE: Our purpose was to prospectively evaluate the interobserver reliability of digital and endovaginal ultrasonographic cervical length measurements. STUDY DESIGN: Forty-three women were recruited from our antepartum clinic to participate in this study. Two independent and blinded digital cervical examinations were performed by the first author and a second examiner. Instructions were given to estimate the cervical length in millimeters. After micturition endovaginal ultrasonographic cervical length measurements were performed by two independent, blinded registered diagnostic medical sonographers. Cervical lengths were compared with the Student t test and Pearson's correlation coefficient. A kappa statistic was calculated for interobserver reliability at three levels of agreement +/- 1 mm, +/- 4 mm, and +/- 10 mm. Data are expressed as means +/- SD. RESULTS: Digital cervical lengths were not different between the two examiners (18.7 +/- 4.8 mm, 20.5 +/- 6.2 mm) nor between the two ultrasonographic measurements (38.6 +/- 6.1 mm, 39.2 +/- 5.4 mm). The digital cervical lengths agreed (+/- 1 mm) 35% of the time (R2 0.10, p = 0.02). The endovaginal ultrasonographic measurements agreed (+/- 1 mm) 74% of the time with a stronger correlation (R2 0.53, p = 0.0001). The kappa statistic for interobserver variability was marginal for both digital and endovaginal cervical length measurements when agreement was defined as +/- 1 mm. Endovaginal ultrasonography was significantly more reliable than digital examination when agreement between examiners was defined as either +/- 4 mm or +/- 10 mm. CONCLUSION: Although both digital and endovaginal ultrasonographic cervical length measurements show correlation between examiners, endovaginal ultrasonography is significantly more reliable when agreement is defined as > or = +/- 4 mm. Serial cervical length measurements to predict preterm labor will be enhanced by the interobserver reliability of endovaginal ultrasonography. PMID- 9369834 TI - Limited clinical utility of midtrimester fetal morphometric percentile rankings in screening for birth weight abnormalities. AB - OBJECTIVE: Our purpose was to determine whether midtrimester fetal ultrasonographic morphometric percentile rankings are sensitive screening tests for preterm labor or birth weight abnormalities. STUDY DESIGN: Stepwise multiple regression and chi 2 analysis were used to identify midtrimester fetal measurements predicting birth weight and gestational age. Receiver-operator characteristics curves were used to evaluate abdominal circumference percentiles as a test for large-for-gestational-age and small-for-gestational-age infants. RESULTS: Extremes in abdominal circumference and head measurement percentiles were associated with large- and small-for gestational-age infants but not with preterm delivery. Abdominal circumference predicted birth weight in regression analysis; however, receiver-operator characteristic curves showed abdominal circumference percentiles to be poor screening tests for large- or small-for gestational-age infants. The positive predictive value of 10th and 90th abdominal circumference percentiles for small- and large-for-gestational-age infants was < 20%. CONCLUSION: Midtrimester percentile rankings offer no clear benefit in targeting fetuses with potential birth weight abnormalities or risk of preterm delivery and may provide clinically misleading information. PMID- 9369835 TI - Suspected skeletal dysplasias: femur length to abdominal circumference ratio can be used in ultrasonographic prediction of fetal outcome. AB - OBJECTIVES: Skeletal dysplasias are a group of bone growth disorders, some of which can be recognized prenatally. Certain types of skeletal dysplasias result in a lethal fetal outcome. The ability to predict this outcome prenatally would be important in counseling parents. This study evaluated the ratio of femur length to abdominal circumference as a predictor of fetal outcome in cases of suspected skeletal dysplasia. STUDY DESIGN: This 3-year retrospective study identified 18 cases of prenatally suspected skeletal dysplasia from a population of approximately 35,000 fetuses undergoing prenatal ultrasonography. The femur length/abdominal circumference ratio was calculated and compared with fetal neonatal outcomes and diagnoses. RESULTS: Eighteen cases of suspected skeletal dysplasia were identified, and the femur length/abdominal circumference ratio was found to be a good predictor of fetal outcome independent of gestational age. A ratio < 0.16 resulted in a lethal outcome in nine of nine cases. Conversely, a ratio > or = 0.16 resulted in a diagnosis of a nonlethal form of skeletal dysplasia or a diagnosis that ruled out any form of skeletal dysplasia in nine of nine cases. CONCLUSIONS: The femur length/abdominal circumference ratio may be useful to predict a lethal fetal outcome when ultrasonography indicates a possible skeletal dysplasia. PMID- 9369836 TI - Intrapartum airway management for giant fetal neck masses: the EXIT (ex utero intrapartum treatment) procedure. AB - OBJECTIVE: Our goal was to review our experience with the EXIT (ex utero intrapartum treatment) procedure in the management of five cases with life threatening fetal neck masses. STUDY DESIGN: We present a retrospective review of prenatal presentation and course, diagnostic accuracy of imaging studies, intraoperative management, complications, and outcomes. RESULTS: Polyhydramnios was the initial presenting symptom in three of five fetuses with a mean gestational age of 25 +/- 6 weeks. Preterm labor occurred in two patients. Fetal magnetic resonance imaging provided accurate diagnosis in all four cases whereas conventional ultrasonography led to the diagnosis in four of five cases. The mean duration of EXIT was 28 +/- 22 minutes. The mean venous cord blood gas values were pH 7.22 +/- 0.05, PCO2 61 +/- 11 mm Hg, and PO2 42 +/- 8 mm Hg. In four of five cases an airway was successfully secured. CONCLUSIONS: The EXIT procedure provides up to 1 hour of good uteroplacental support and is the procedure of choice to secure an airway in the fetus with a giant neck mass. PMID- 9369837 TI - The geriatric gravida: multifetal pregnancy reduction, donor eggs, and aggressive infertility treatments. AB - OBJECTIVE: Recent technologic advances and societal acceptance have dramatically increased the use of donor eggs for infertile couples who require assisted reproductive technologies. Now many "older" couples can access assisted reproductive technologies to achieve pregnancies. We sought to evaluate the changing pattern of patients referred for multifetal pregnancy reduction as a result of donor eggs and age factors in aggressive infertility treatment. STUDY DESIGN: Patients undergoing multifetal pregnancy reduction from 1986 to 1996 were included and categorized by year groupings, age, and the use of donor eggs. RESULTS: A total of 523 patients were referred for and underwent multifetal pregnancy reduction. Before 1994, only 4 of 226 (1.8%) had received donor eggs, whereas in 1994 to 1996, 29 of 297 (9.8%) had received donor eggs (chi 2 = 12.6, p < 0.001). Eight of 9 patients aged > or = 45 years undergoing multifetal pregnancy reduction received donor eggs. There were no patients aged > or = 45 years before 1994 but 9 in 1994 to 1996. Four of 9 patients aged > or = 45 years with multifetal pregnancies chose reduction to singleton gestation. The proportions of patients aged > or = 40 years have increased from 0% to 11% in the last 8 years. CONCLUSIONS: The availability of donor eggs has dramatically increased the use of assisted reproductive technologies and subsequent use of multifetal pregnancy reduction in older patients. Older patients are more inclined to want reduction to singleton gestation; they cite parental demands, financial issues, and their ability to parent in their 60s and 70s as reasons for reduction to singleton gestation. PMID- 9369838 TI - Maternal serum analyte levels in pregnancies with fetal Down syndrome resulting from translocations. AB - OBJECTIVE: Our purpose was to determine whether pregnancies affected by fetal Down syndrome resulting from Robertsonian translocations are associated with second-trimester maternal serum analyte levels different from those resulting from fetal trisomy 21. STUDY DESIGN: Pregnancies with Down syndrome caused by Robertsonian translocations were identified through the cytogenetics laboratories at the participating institutions. Those with maternal serum screening values between 15 and 20 weeks were evaluated. RESULTS: Eleven cases of fetal Down syndrome caused by Robertsonian translocations were identified. The median alpha fetoprotein, unconjugated estriol, and human chorionic gonadotropin levels were 0.68, 0.67, and 2.83 multiples of the median, respectively. These analyte levels are similar to those for fetal trisomy 21. CONCLUSIONS: These data suggest that Down syndrome resulting from either Robertsonian translocations or trisomy 21 will be detected in a similar percentage of cases because the second-trimester maternal serum analyte levels are similar. PMID- 9369839 TI - Precise gaussian distribution functions of maternal serum alpha-fetoprotein and free beta-subunit of human chorionic gonadotropin for trisomy 21 screening: improved accuracy for patient counseling. AB - OBJECTIVE: Gaussian equation curves are used to generate baseline curves against which a priori maternal age Down syndrome risks are adjusted to develop likelihood ratios for individual patients. We sought to evaluate the accuracy of these calculations, minimize the affects of outliers, and to make improvements. STUDY DESIGN: Gaussian distribution functions were used to investigate the best model for alpha-fetoprotein and free beta-human chorionic gonadotropin multiples of the median with use of nonlinear regressions. Parameters from distribution functions can be used to compute a more precise likelihood ratio for the decision logic for trisomy 21. A total of 58,297 normal cases and 348 cases of trisomy 21 were computed. RESULTS: Log normal distribution functions generated by nonlinear regression produced excellent but exaggerated goodness of fit R2 to the frequency distributions of the data. For normal cases values were as follows (in mean, SD, and R2, respectively): log alpha-fetoprotein -0.07199, 0.15681, and 0.9970; log beta-human chorionic gonadotropin -0.15203, 0.24284, and 0.9987. For trisomy 21 cases the values were (in mean, SD, and R2, respectively) for log alpha fetoprotein -0.19303, 0.15802, and 0.9828 and for log beta-human chorionic gonadotropin 0.19996, 0.29760, and 0.9669. Distributions reconstructed with use of statistical means and SDs generated goodness of fit R2 from 0.585 to 0.914. Use of means and SDs derived from distribution functions increased the R2 to 0.855 and 0.999. The change in the model produces, at a 5% false-positive rate, a sensitivity of 57.18% (199/348). A 1 in 113 cutoff point risk is obtained and is tighter than the 1 in 251 without the distribution functions, as versus 1 in 270 by age calculations alone. CONCLUSIONS: Our data suggest that (1) normality of log transforms of alpha-fetoprotein and normality of log transforms of beta-human chorionic gonadotropin are reasonable models, (2) distribution functions can minimize the effect of outliers, which produces more realistic risk estimates, and (3) the effect of distribution functions versus standard mean and SDs cannot automatically be extrapolated to other parameters, which must be tested individually. PMID- 9369840 TI - Third-generation oral contraceptive and deep venous thrombosis: from epidemiologic controversy to new insight in coagulation. AB - Four epidemiologic studies showed a twofold increase in risk of deep venous thrombosis with the use of oral contraceptives containing third-generation progestins, relative to second-generation products. These findings have been strongly debated ever since, and new studies have been added. In the current article we examine whether the findings can be explained by potential biases or other shortcomings of the epidemiologic studies. We conclude that complete certainty cannot exist but that the most rational conclusion from the epidemiologic findings and their discussion is that an increased risk of deep venous thrombosis with third-generation contraceptives is likely, especially in first-time and young users. The controversy has recently led to new insights in coagulation: Women who use third-generation contraceptives acquire a resistance to the blood's own anticoagulation system, similar to the activated protein C resistance that is seen in persons who carry the factor V Leiden mutation but different from that in women using second-generation contraceptives. PMID- 9369841 TI - Is the academic physician-scientist an oxymoron in contemporary obstetrics and gynecology? AB - Because of changes in health care reimbursement and decreasing federal funding, academic obstetrics and gynecology is at a pivotal point. Either the discipline can regress to the past, when the field and its practitioners were viewed negatively and failed to attract the academic upper echelons of medical students, or it can build on the immense gains it has made in recent years and develop a critical cadre of well-trained clinician-scientists who maintain the discipline at the leading edge of medicine and biology. Data from two programs in which extensive contemporary training in biomedical research is provided, the Reproductive Scientist Development Program and the American Association of Obstetricians and Gynecologists Foundation fellowship program, indicate that the superb physician-scientists in these programs are obtaining peer-reviewed funding in excess of 70%. Thus the risk of recruiting such individuals to academic faculties is small. More important, these individuals are the linchpins for an even more exciting future. The alternatives are unthinkable. PMID- 9369842 TI - Prenatal diagnosis of fetal varicella-zoster virus infection with polymerase chain reaction of amniotic fluid in 107 cases. AB - OBJECTIVE: Varicella, resulting from primary infection by varicella zoster virus, carries a risk of severe congenital varicella. Prenatal diagnosis is rarely applied because methods remain to be validated. STUDY DESIGN: From 1989 to 1994, 107 women contracted clinical varicella before 24 weeks of pregnancy. Amniocentesis was performed in all cases, with simultaneous fetal blood sampling in 82 cases. Virus was detected in amniotic fluid by cell culture inoculation and polymerase chain reaction. Fetal blood was tested for anti-varicella zoster virus immunoglobulin M. RESULTS: Of the 107 amniotic fluid samples tested, nine of 107 (8.4%) were positive by polymerase chain reaction, but only two of these (1.8%) were positive in cell culture; none of the blood samples from infected fetuses were positive for specific anti-varicella zoster virus immunoglobulin M. The outcome of 99 pregnancies was fully documented. CONCLUSION: The risk of transplacental passage before 24 weeks of pregnancy was 8.4% in our series. The risk of congenital varicella is 3 in 107 (2.8%) and that of isolated postnatal varicella zoster infection is 3 in 78 (3.8%). Polymerase chain reaction is more sensitive than cell culture for the detection of varicella zoster virus in amniotic fluid. PMID- 9369843 TI - Quantitative fluorescence polymerase chain reaction for the rapid prenatal detection of common aneuploidies and fetal sex. AB - OBJECTIVE: We have developed a quantitative fluorescence multiplex polymerase chain reaction assay for the rapid detection of sex and aneuploidies involving chromosomes 21, 18, and 13. STUDY DESIGN: Samples of deoxyribonucleic acid (n = 85) extracted from amniotic fluid, fetal tissues, and blood were investigated by multiplex polymerase chain reaction amplification of polymorphic small tandem repeat markers specific for chromosomes 21, 18, 13, and X. RESULTS: Quantitative analysis of the polymerase chain reaction products allowed us to distinguish between normal samples and samples with autosomal trisomies while sexing was performed simultaneously. From 85 samples only three produced unsatisfactory results with one of the two chromosome 13-specific markers. In these three cases the amplification of the other chromosome 13 marker always resulted in a correct normal pattern. CONCLUSION: Quantitative fluorescence multiplex polymerase chain reaction is a reliable and rapid method that allows prenatal diagnosis of the major numeric chromosomal abnormalities to be performed within 24 hours. PMID- 9369844 TI - Involvement of nitric oxide pathway in prostaglandin F2 alpha-induced preterm labor in rats. AB - OBJECTIVE: Our purpose was to investigate the roles of nitric oxide and prostaglandins in controlling parturition. STUDY DESIGN: Pregnant rats on day 18 of gestation were injected intraperitoneally with prostaglandin F2 alpha, prostaglandin F2 alpha plus diethylenetriamine-nitric oxide (a donor of nitric oxide), prostaglandin F2 alpha plus diethylenetriamine without nitric oxide, or vehicle. Uterine nitrite production, nitric oxide synthase messenger ribonucleic acid and contractile response in vitro, and serum progesterone levels were measured. The labor and delivery of the rats also were monitored. RESULTS: Exogenously administered prostaglandin F2 alpha significantly inhibited nitric oxide production by the uterus in a time-dependent manner with maximal effects observed 48 hours after prostaglandin F2 alpha treatment. Messenger ribonucleic acid for inducible nitric oxide synthase but not endothelial nitric oxide synthase messenger ribonucleic acid in the uterus was significantly inhibited by prostaglandin F2 alpha with maximal inhibition at 48 hours after prostaglandin F2 alpha injection. The serum progesterone concentration was substantially reduced by prostaglandin F2 alpha, and this reduction was partially reversed by administration of diethylenetriamine-nitric oxide but not diethylenetriamine without nitric oxide. Prostaglandin F2 alpha caused increases in contractile activity of the uterus in a dose-dependent manner. Diethylenetriamine-nitric oxide (10(-4) mol/L) blocked prostaglandin F2 alpha-induced contractions. Premature parturition was induced within 48 hours after prostaglandin F2 alpha injection in 100% of the animals. Coadministration of diethylenetriamine-nitric oxide completely prevented the preterm labor induced by prostaglandin F2 alpha. CONCLUSION: Prostaglandin F2 alpha inhibited inducible nitric oxide synthase messenger ribonucleic acid and subsequent nitric oxide generation in the rat uterus. Nitric oxide can prevent prostaglandin F2 alpha-induced preterm labor, possibly by attenuating the fall in serum progesterone and blocking uterine contractions induced by prostaglandin F2 alpha administration. PMID- 9369846 TI - Vaginal ultrasonography versus endometrial biopsy in women with postmenopausal bleeding. AB - OBJECTIVE: Our goal was to compare the predicted outcomes and costs of two diagnostic algorithms for postmenopausal bleeding. STUDY DESIGN: Two algorithms for postmenopausal bleeding were developed, one with vaginal ultrasonography and the other with office endometrial biopsy as the first test. Literature review was performed to estimate the probability of either an abnormal result of ultrasonography or a nondiagnostic biopsy, or both. Cost and sensitivity analyses were performed. RESULTS: Estimated probability of a nondiagnostic endometrial biopsy was 28%, and estimated probability of an abnormal result of vaginal ultrasonography (either inconclusive or endometrial thickness > 4 mm) was 55%. Cost analysis showed that vaginal ultrasonography as the first diagnostic test cost $230 per patient on average compared with $244 for endometrial biopsy, with savings ranging from $14 to $20 per patient over a wide range of possible values for estimated parameters. CONCLUSION: Vaginal ultrasonography costs slightly less than office endometrial biopsy as the first test in the diagnostic evaluation of women with postmenopausal bleeding. PMID- 9369845 TI - Antiphospholipid immunoglobulin G antibodies reduce annexin-V levels on syncytiotrophoblast apical membranes and in culture media of placental villi. AB - OBJECTIVES: The mechanism by which antiphospholipid antibodies are associated with pregnancy loss and thromboembolism has not been established. We previously showed that annexin-V, a phospholipid-binding protein with potent anticoagulant activity, is present on the apical membranes of the syncytiotrophoblasts that line placental villi and that this protein is reduced, by immunohistochemistry, on placentas of patients with antiphospholipid antibodies. We therefore investigated whether annexin-V in apical membranes of placental villi is quantitatively reduced by antiphospholipid antibody immunoglobulin G. STUDY DESIGN: Placentas were obtained from an index patient with antiphospholipid syndrome with intrauterine growth restriction and from a patient with an uncomplicated pregnancy who were both delivered by cesarean section. Apical villous membranes were isolated and annexin-V levels were measured by enzyme linked immunosorbent assay. We then studied the effects of antiphospholipid immunoglobulin G on placental villous apical annexin-V in vitro. Antiphospholipid immunoglobulin G was isolated from the sera of five different patients with antiphospholipid antibody syndrome along with five paired control immunoglobulin Gs. Short-term cultures were established from normal placental villi and were exposed to the antibodies, after which isolated apical membranes and culture media were immunoassayed for annexin-V levels. RESULTS: Measurements of apical membrane-associated annexin-V from the antiphospholipid placenta showed significantly less apical membrane-associated annexin-V than did the normal placenta (mean +/- SEM: 4.9 +/- 0.4 micrograms/gm villi for antiphospholipid placenta vs 10.2 +/- 0.6 micrograms/gm villi for control, p < 0.001, n = 4). Exposure of placental villous cultures to five different antiphospholipid immunoglobulin Gs for 24 hours resulted in significant reduction of the levels of apical membrane annexin-V (mean +/- SEM: 3.9 +/- 0.3 micrograms/gm villi) compared with paired controls (5.1 +/- 0.3 micrograms/gm villi, p = 0.02). Villi incubated with the different antiphospholipid immunoglobulin Gs had significantly less annexin-V in conditioned media (mean +/- SEM: 45.1 +/- 4.9 ng/gm villi) compared with the paired normal immunoglobulin G control levels (72.6 +/- 11.4 ng/gm villi, p = 0.03). CONCLUSIONS: Antiphospholipid immunoglobulin G reduces the levels of syncytiotrophoblast apical membrane-associated annexin-V in placental villi and the release of annexin-V into surrounding media. Reduction of this anticoagulant protein at the maternal-fetal interface may account for the pregnancy loss observed in patients with antiphospholipid syndrome. Short-term culture of placental villi may offer an in vitro model to further study the mechanism of this effect of antiphospholipid antibodies. PMID- 9369847 TI - Human papillomavirus testing as triage for atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesions: sensitivity, specificity, and cost-effectiveness. AB - OBJECTIVE: Our purpose was to evaluate the cost-effectiveness of the use of a Food and Drug Administration-approved human papillomavirus test in triaging patients with Papanicolaou smears showing atypical squamous cells of undetermined significance or a low-grade squamous intraepithelial lesion for colposcopy compared with an algorithm that used cytologic follow-up. STUDY DESIGN: Four hundred sixty-two women referred to our Colposcopy Clinic with a Papanicolaou smear report of atypical squamous cells of undetermined significance or a low grade squamous intraepithelial lesion underwent repeat Papanicolaou smear, cervical colposcopy, directed cervical biopsy, and endocervical curettage. In addition, human papillomavirus testing by the Food and Drug Administration approved HPV Profile (Digene Diagnostics, Silver Spring, Md.) test was done. A comparison of sensitivity, specificity, and cost-effectiveness of an algorithm determining the need for colposcopy on the basis of repeat cytologic testing versus an algorithm that incorporated repeat cytologic testing and human papillomavirus screening was done. The cost-effectiveness of both of these triage algorithms was also compared. RESULTS: As expected, high-risk human papillomavirus deoxyribonucleic acid was detected with greater frequency in relation to increasing severity of cervical intraepithelial neoplasia. In 268 women, the follow-up smear obtained in our clinic was reported as negative. High risk human papillomavirus types were found in 23.5% of these women. In the human papillomavirus-negative women, 5.9% had grade 2 or 3 cervical intraepithelial neoplasia confirmed on cervical biopsy. In comparison, 20.6% of those with a positive result of the human papillomavirus test had grade 2 or 3 cervical intraepithelial neoplasia on biopsy (p < 0.001). Despite this difference, the sensitivity of a positive result of a high-risk human papillomavirus test in predicting the presence of grade 2 or 3 cervical intraepithelial neoplasia was only 52%. Among the women for whom a follow-up clinic Papanicolaou smear was reported as showing atypical squamous cells of undetermined significance or a low grade squamous intraepithelial lesion, there was no difference in the frequency of biopsy-proved grade 2 or 3 cervical intraepithelial neoplasia between those women with a positive human papillomavirus test result and those with a negative test result. Colposcopy would have been recommended for 194 women because of a repeat clinic smear revealing atypical squamous cells of undetermined significance, a low-grade squamous intraepithelial lesion, or a high-grade squamous intraepithelial lesion, and in 21.6% of these grade 2 or 3 cervical intraepithelial neoplasia was shown on biopsy (sensitivity 63%, specificity 62%). Colposcopy would have been recommended for 180 women because high-risk human papillomavirus or a high-grade squamous intraepithelial lesion was detected at the clinic visit, and in 25% of this group grade 2 or 3 cervical intraepithelial neoplasia was shown on biopsy (sensitivity 67%, specificity 66%). Sensitivity and specificity were virtually identical for the two algorithms, but the cost of human papillomavirus testing was nearly double that of triage based on repeat cytologic testing alone ($692 vs $1246 per case). CONCLUSION: The Food and Drug Administration-approved HPV Profile test is not a cost-effective triage for patients referred with Papanicolaou smears reported as showing atypical squamous cells of undetermined significance or low-grade squamous lesions. PMID- 9369848 TI - Randomized, double-blind, dose-ranging study of the endometrial effects of a vaginal progesterone gel in estrogen-treated postmenopausal women. AB - OBJECTIVE: Our purpose was to assess the endometrial effects of two doses of natural progesterone administered by a bioadhesive vaginal gel in estrogen treated postmenopausal women. STUDY DESIGN: This was a double-blind, randomized, dose-ranging study of 31 postmenopausal women attending a specialist menopause clinic. Endometrial histologic features, sex steroid hormone concentrations, and vaginal bleeding patterns were assessed during three 28-day cycles of continuous oral conjugated estrogens (0.625 mg/day) and two doses of sequential vaginally administered natural progesterone (45 or 90 mg every 48 hours). Histologic results are presented descriptively. Between-group comparisons of other parameters were made with the use of the Mann-Whitney U and Student t tests. RESULTS: Secretory endometrium was found in 35 of 41 histologic samples that yielded adequate tissue for diagnosis. There was one case of proliferative endometrium in the 45 mg progesterone group and none in the 90 mg group and no cases of hyperplasia. Mean plasma progesterone concentrations of 4.6 ng/ml and 6.8 ng/ml were achieved in the 45 and 90 mg groups, respectively. CONCLUSIONS: Very low doses of natural progesterone, when administered vaginally in a bioadhesive gel, cause secretory endometrial transformation in estrogen-treated postmenopausal women. PMID- 9369849 TI - Pregnancy outcomes in women with inflammatory bowel disease--a population-based cohort study. AB - OBJECTIVE: Our purpose was to assess the frequency of adverse pregnancy outcomes in women with inflammatory bowel disease compared with the general population. STUDY DESIGN: Of all 239,773 pregnant women with single births in Sweden from 1991 to 1992, 756 women with inflammatory bowel disease could be analyzed for late fetal and infant death, preterm birth, low birth weight, small for gestational age, and cesarean section. Logistic regression analyses was used to estimate the odds ratios. RESULTS: Pregnancies in women with inflammatory bowel disease were associated with an increased risk of preterm birth at < 33 weeks (odds ratio 1.81, 95% confidence interval 1.06 to 3.07) and at 33 to 36 weeks (odds ratio 1.48, 95% confidence interval 1.10 to 1.99); low birth weight < 1500 gm (odds ratio 2.15, 95% confidence interval 1.11 to 4.15) or 1500 to 2499 gm (odds ratio 1.57, 95% confidence interval 1.12 to 2.22); small for gestational age (odds ratio 1.40, 95% confidence interval 0.97 to 2.02); and cesarean section (odds ratio 1.51, 95% confidence interval 1.27 to 1.89). CONCLUSIONS: Inflammatory bowel disease in pregnant women is associated with an increased frequency of adverse pregnancy outcomes. PMID- 9369850 TI - Prevention of preterm birth in patients with symptoms of preterm labor--the benefits of psychologic support. AB - OBJECTIVE: The aim of this study was to assess the effectiveness of psychologic support against preterm delivery in pregnant women with symptoms of preterm labor. STUDY DESIGN: The study, which involved two cohorts of women identified during two successive periods in the same maternity ward, included 309 women in the experimental group and 323 in the control group. The women in the control group were followed up according to the usual therapeutic procedures, whereas additional psychologic support was offered to the experimental group. The analysis, conducted "in intent to treat," was based on the estimation of the relative risk by a multivariate logistic regression adjusting for confounding factors. RESULTS: A significant decrease in the preterm birth rate was observed in the experimental group (12.3%) compared with the control group (25.7%), with an adjusted relative risk of 0.37 (95% confidence interval 0.30 to 0.47). CONCLUSION: This study confirms the feasibility of this kind of intervention and the effectiveness of psychologic support on the risk of preterm delivery. PMID- 9369851 TI - Congenital adenomatoid malformation of the lung: when is active fetal therapy indicated? AB - OBJECTIVE: Although aggressive fetal therapies such as thoracoamniotic shunting can be applied to cystic adenomatoid malformations of the lung diagnosed in utero, there is no clear consensus regarding their indications. Our purpose was to evaluate a management policy in which aggressive fetal therapy was restricted to those cases complicated by major polyhydramnios or hydrops; all other cases were managed conservatively. STUDY DESIGN: A prospective cohort study of 33 cases with a prenatal diagnosis of cystic adenomatoid malformations of the lung was performed. Thoracoamniotic shunting was offered only in nine macrocystic cases with acute polyhydramnios or hydrops. RESULTS: Four cases were diagnosed postnatally as sequestrations. Of 12 cases complicated by acute polyhydramnios or hydrops, 5 survived (1 type III with spontaneous incomplete resolution in utero, 4 type I with substantial volume reduction after shunting). The 17 cases without acute polyhydramnios or hydrops were managed conservatively and survived. CONCLUSION: Conservative management is indicated in cases of cystic adenomatoid malformations of the lung without acute polyhydramnios or hydrops. PMID- 9369852 TI - External alkalinization decreases intracellular Ca++ and spontaneous contractions in pregnant rat myometrium. AB - OBJECTIVES: As plasma pH rises during pregnancy, the effect of raising external pH on spontaneous contractions in pregnant rat myometrium was investigated to test the hypothesis that elevated external pH depresses contraction. STUDY DESIGN: Strips of longitudinal myometrium were loaded with SNARF (seminaphthorhodafluor) or Indo-1 for simultaneous intracellular pH or Ca++ and force measurements. Results were obtained from a minimum of five animals in each group, and significant differences were tested for by paired Student t tests. RESULTS: Raising the external pH significantly reduced spontaneous force and calcium transient in the pregnant uterus. Raising the external pH led to a slow rise in intracellular pH, but this could not account for the functional effect. K+ rubidium 86-labeled efflux rates were unaffected by external pH, suggesting no hyperpolarization. The Ca++ channel agonist Bay K8644 (5 mumol/L) restored contractions abolished by raised external pH. CONCLUSIONS: Raised external pH reduces spontaneous contractions in the pregnant rat uterus, probably by an external effect on Ca++ entry. This effect may contribute to uterine quiescence before term. PMID- 9369853 TI - Antiphosphatidylserine antibody removes annexin-V and facilitates the binding of prothrombin at the surface of a choriocarcinoma model of trophoblast differentiation. AB - OBJECTIVE: Trophoblast differentiation is associated with externalization of phosphatidylserine from the inner to the outer surface of the plasma membrane. In this study we tested the hypothesis that concurrent externalization and binding of annexin-V blocks the phosphatidylserine-rich surface from acting as a site for activation of coagulation and that antiphospholipid antibodies lead to a procoagulant state by preventing annexin-V binding. STUDY DESIGN: A choriocarcinoma model of trophoblast differentiation, forskolin-activated BeWo cells and immunoperoxidase techniques were used to determine surface and cytoplasmic localization of annexin-V related to differentiation. Monoclonal immunoglobulin M antibodies against phosphatidylserine- and cardiolipin-dependent antigens were used to determine the effects of antiphospholipid antibodies on annexin-V localization and on the binding of prothrombin to the BeWo surface. RESULTS: During differentiation BeWo cells externalized phosphatidylserine and increased the expression of surface annexin-V. Monoclonal antibody against phosphatidylserine removed annexin-V from the BeWo surface and increased binding of prothrombin. CONCLUSION: Antiphosphatidylserine antibody induces sites for prothrombin binding on the surface of a BeWo model of trophoblast, most likely by removing annexin-V. This mechanism could explain the frequent observation of increased thrombosis at the maternal-fetal interface in miscarriages associated with antiphospholipid antibodies. PMID- 9369854 TI - The quality of citations in major international obstetrics and gynecology journals. AB - OBJECTIVE: Our goal was to determine the error rate in references in articles published in three major international journals in obstetrics and gynecology. STUDY DESIGN: All issues (excluding supplements) for the year 1995 of the American Journal of Obstetrics and Gynecology, the Australian and New Zealand Journal of Obstetrics and Gynaecology, and the British Journal of Obstetrics and Gynaecology were examined. References were numbered sequentially, and 50 randomly selected references from each journal were checked against the original for accuracy. RESULTS: Errors were found in the majority of references. The lowest error rate was 55.6% from the Australian and New Zealand Journal of Obstetrics and Gynaecology, and the highest was 66.7% from the British Journal of Obstetrics and Gynaecology. The difference between journals was not statistically significant. The most frequent types of error were in the title of the article or in the authors' names. CONCLUSIONS: Error rates in major international journals in obstetrics and gynecology are high, and care must be taken by authors and journal staff to improve the quality of published articles. PMID- 9369855 TI - Anesthesia: part of the solution. PMID- 9369856 TI - Mechanism of intrauterine device contraceptive action. PMID- 9369857 TI - The intrauterine contraceptive device: an acceptable alternative to sterilization in young women. PMID- 9369858 TI - Abbot Purchart I (928-971) of St. Gallen--born by postmortem cesarean section. PMID- 9369859 TI - Possible roles of long-chain fatty acids in preterm birth. PMID- 9369860 TI - No evidence to support intrauterine contraceptive device and embryo destruction. PMID- 9369861 TI - Intrauterine contraceptive devices act before fertilization. PMID- 9369862 TI - The management of persistent adnexal masses in pregnancy. PMID- 9369863 TI - Which human chorionic gonadotropin? Which analyte? PMID- 9369864 TI - Colposuspension and the possibility of recurrent cystocele. PMID- 9369865 TI - Accidental electric shock in pregnancy: a prospective cohort study. PMID- 9369866 TI - True natural history of transfundal pressure. PMID- 9369867 TI - Quality. An elusive goal with a clear path. PMID- 9369868 TI - The impact of birth defects and genetic diseases. PMID- 9369869 TI - Development of a quality of care measurement system for children and adolescents. Methodological considerations and comparisons with a system for adult women. AB - OBJECTIVES: To describe the development of a pediatric quality of care measurement system designed to cover multiple clinical topics that could be applied to enrollees in managed care organizations and to compare the development of this system with the concurrent development of a similar system for adult women. DESIGN: Indicators were developed for 21 pediatric (ages 0-18 years) clinical topics and 20 adult (ages 17-50 years) women's clinical topics. Indicators were classified by the strength of evidence supporting them. A modified Delphi method was used to obtain validity and feasibility ratings from a pediatric expert panel and an adult women's expert panel. Indicators were categorized by type of care (preventive, acute, or chronic), function (screening, diagnosis, treatment, or follow up), and modality (history, physical examination, laboratory/radiology study, medication, other intervention, or other contact). RESULTS: Of 557 pediatric and 391 adult women's proposed indicators, 453 (81%) and 340 (87%), respectively, were retained by the 2 expert panels. A lower percentage of final pediatric indicators than adult indicators were based on randomized, controlled trials and other rigorous studies (18% vs 40%, P < .001). The expert panels were more likely to retain indicators based on rigorous studies (93% retained) than on descriptive studies and expert opinion (81% retained, P < .001). A higher percentage of pediatric indicators than women's indicators were for preventive care (30% vs 11%, P < .001) and a lower percentage were for acute care (36% vs 49%, P < .001) or chronic care (34% vs 41%, P = .06). CONCLUSIONS: This study contributes to the field of pediatric quality of care assessment by providing many more indicators than have been available previously and by documenting the strength of evidence supporting these indicators. Formal consensus methods are essential for the development of pediatric quality measures because the evidence base for pediatric care is more limited than for adult care. PMID- 9369870 TI - Contribution of birth defects and genetic diseases to pediatric hospitalizations. A population-based study. AB - OBJECTIVE: To estimate the contribution of birth defects and genetic diseases to pediatric hospitalizations by use of population-based data. DESIGN: Hospital discharges were categorized according to the diagnostic codes of The International Classification of Diseases, Ninth Revision, Clinical Modification. Hospitalizations that were related to birth defects and genetic diseases were compared with hospitalizations for other reasons, with respect to age, race/ethnicity, sex, length of stay, charges, source of payment, and mortality rate. Hospitalization rates and per capita charges were computed with the use of population estimates from 1990 census data. MATERIALS: The 1991 population-based hospital discharge data from California and South Carolina. RESULTS: Nearly 12% of pediatric hospitalizations in the 2 states combined were related to birth defects and genetic diseases. These children were, on average, about 3 years younger, stayed 3 days longer in a hospital, incurred 184% higher charges, and had a 4 1/2 times greater in-hospital mortality rate than children who were hospitalized for other reasons. The rate of hospitalizations that were related to birth defects and genetic diseases was 4 per 1000 children in both states, but these rates varied by age and race. CONCLUSION: These population-based data are the first contemporary findings to show the substantial morbidity rate and hospitalization charges associated with birth defects and genetic diseases in the pediatric population. IMPLICATIONS: This information is important for planning effective health care strategies, especially as the causes, treatments, and prevention of these disorders are being further elucidated by findings from human genome research and epidemiologic studies. PMID- 9369871 TI - The effect of health maintenance organization vs commercial insurance status on obstetrical management and outcome. AB - OBJECTIVE: To compare obstetrical management and birth outcomes between patients with health maintenance organization (HMO) insurance and those with private commercial insurance. DESIGN: Retrospective population-based cohort study. SETTING: King County, Washington. PATIENTS: Among newborns delivered in 1992 and 1993, a random sample of 4000 birth records listing HMO insurance for prenatal care was compared with a random sample of 4000 birth records listing private commercial insurance as the primary coverage. MAIN OUTCOME MEASURES: Use of ultrasonography and amniocentesis; rate of primary cesarean section performed; adequacy of prenatal care; incidence of maternal medical complications, low birth weight, and congenital malformations; and length of hospital stay. RESULTS: Women covered by HMO compared with commercial insurance were more likely to undergo ultrasonography (relative risk [RR], 1.4; 95% confidence interval [CI], 1.3-1.4). Inadequate prenatal care was less frequent among HMO-insured patients (RR, 0.6; 95% CI, 0.5-0.7), as was the incidence of birth weight below 2500 g (RR, 0.7; 95% CI, 0.6-0.9). No differences in rates of cesarean section and congenital anomalies were observed. Among women without obstetrical risk factors, HMO insured mothers were at an increased risk of labor and delivery complications (RR, 1.4; 95% CI, 1.3-1.5); their infants were at an increased risk of infant distress (RR, 1.8; 95% CI, 1.5-2.2). CONCLUSIONS: Patients with HMO insurance have improved access to prenatal care and screening when compared with privately insured patients. The reasons for increased risks of abnormal maternal and infant outcomes observed among a subset of HMO-insured patients are unclear. A study with more detailed prospective data collection is warranted. PMID- 9369872 TI - Insurance status and recognition of psychosocial problems. A report from the Pediatric Research in Office Settings and the Ambulatory Sentinel Practice Networks. AB - OBJECTIVE: To examine the effect of insurance status on clinician recognition of psychosocial problems for pediatric primary care visits. DESIGN: A cohort study of 10,250 visits by children 4 to 15 years old for nonemergent care. SETTING: Two large primary care research networks reported data from 172 primary care clinicians in office-based practice. PATIENTS: Ten thousand two hundred and fifty unique children presenting consecutively to participating physicians for nonemergent services with a parent or caregiver. MAIN OUTCOME MEASURE: Children were classified as positive for psychosocial problems if their score on the parent-reported Pediatric Symptom Checklist exceeded the standard cutoff of 28. Clinician recognition was obtained by report as a dichotomous variable. Insurance status was categorized by payor and plan structure. RESULTS: Clinicians did not recognize psychosocial problems for a substantial number of children with scores suggestive of marked psychosocial dysfunction on the Pediatric Symptom Checklist. Insurance type was not associated with rates of recognition. However, provider familiarity with patients, provider discipline, and patient demographics were associated with increased recognition of psychosocial problems. CONCLUSIONS: Differences in treatment among various insurance groups documented in prior studies are not likely to be related to varying recognition rates, but rather to availability and choices of treatment by insurers, families, and clinicians. Continuity of care was the strongest predictor of clinician recognition. PMID- 9369873 TI - Impact of a new universal purchase vaccine program in North Carolina. AB - OBJECTIVE: To explore the effects of state universal purchase (UP) of vaccines for all children, regardless of income or insurance status, on North Carolina physicians and families. DESIGN: Cross-sectional survey. PARTICIPANTS: Pediatricians and family physicians (N = 2163) were surveyed in 1995 to compare immunization charges in North Carolina (new UP) with those of Massachusetts (UP) and Texas (free market). MAIN OUTCOME MEASURES: Patient charges for immunizations and well-child visits and physician perceptions of the effects of state immunization programs. Models were devised to simulate the net effect of the North Carolina UP program on immunization revenue for physicians and on families' out-of-pocket costs for well-child care. RESULTS: Physician participation rates in the 2 UP programs were very high. North Carolina physicians reported substantial decreases in immunization charges and reduced referrals to public clinics, but thought that UP increased their administrative burden. Sixty percent of North Carolina physicians increased charges for well-child visits, nearly twice that in the 2 control states. Families who previously had received immunizations from public clinics but chose to remain in the private-sector "medical home" for immunizations after implementation of UP had increased out-of pocket expenses that varied by their insurance status. CONCLUSIONS: The North Carolina UP program is effective in decreasing patient immunization charges and reducing referrals to public clinics. However, UP does not eliminate cost as a barrier to immunization, nor does it enable all children to remain in their medical homes. Underinsured children still may face considerable financial barriers to immunization in a UP system. PMID- 9369874 TI - Variation in the management of pediatric diabetic ketoacidosis by specialty training. AB - OBJECTIVE: To compare management strategies for pediatric diabetic ketoacidosis (DKA) among physicians with different specialty training. METHODS: We conducted a mail survey of 1000 randomly selected physicians, including 200 pediatric endocrinologists, 200 general emergency physicians, 200 pediatric emergency physicians, 200 pediatric intensivists, and 200 pediatric chief residents. We posed questions regarding a hypothetical 10-year-old patient with new onset of diabetes mellitus who is approximately 10% dehydrated but alert, with venous pH of 7.1 and serum glucose concentration of 34.7 mmol/L (625 mg/dL). Questions involved the rate of rehydration, content of intravenous fluids, insulin therapy, potassium replacement, use of sodium bicarbonate, and adjustments in therapy for decreasing serum glucose concentration. We compared responses of physicians in each specialty and used multiple regression analysis to adjust for potential confounding variables, including number of years in practice, number of children with DKA seen per month, and practice setting. RESULTS: Five hundred eighty-one physicians (58.1%) completed the survey, with responses demonstrating significant, consistent differences between specialties. Extremes of responses included the following: (1) 59% of endocrinologists vs 11% of general emergency physicians would give an initial fluid bolus of less than 20 mL/kg (odds ratio [OR], 11.7; 95% confidence interval [CI], 5.0-27.7) (P < .001); (2) 83.5% of general emergency physicians vs 42.5% of pediatric intensivists would administer an initial insulin bolus (OR, 4.1; 95% CI, 2.0-8.7) (P < .001); (3) 58.2% of pediatric intensivists vs 9% of general emergency physicians would replace fluids over a period of greater than 24 hours (OR, 14.1; 95% CI, 5.5-37.5) (P < .001); and (4) 54.3% of general emergency physicians vs 7.3% of pediatric intensivists would use potassium chloride alone for potassium replacement (OR, 10.8; 95% CI, 5.0-23.8) (P < .001). All of these differences persisted after adjusting for the potential confounding variables. CONCLUSIONS: Substantial differences exist in the management of pediatric DKA among physicians of different specialties, presumably due to differences in specialty training. These differences obscure our ability to evaluate the treatment of DKA and highlight the necessity for further studies comparing the outcomes of different treatment strategies. PMID- 9369875 TI - Sun protection counseling by pediatricians. AB - OBJECTIVE: To establish a national baseline regarding pediatricians' sun protection counseling perceptions and behaviors. INTERVENTIONS: A survey was mailed to a random sample of 600 pediatricians selected from the 1996 American Academy of Pediatrics Directory using a 3-wave mailing technique to maximize the response rate. The 3-wave mailing resulted in 414 returned surveys of 583 surveys (17 surveys were nondeliverable) (a 71% response rate). RESULTS: Most (60%) of the pediatricians lacked formal training on how to counsel parents and children about sun protection. Approximately 3 (78%) of 4 indicated that not enough time was spent in their residency program on how to educate parents and children about sun protection. Greater than half (60%) of the respondents indicated that they usually (47%) or always (13%) counseled about sun protection. Seventy-seven percent of the respondents indicated that pediatricians have a professional responsibility to counsel parents and children about sun protection. CONCLUSIONS: The results of this investigation suggest that most pediatricians surveyed believed that they had a professional responsibility to counsel about sun protection and that such counseling would be effective in decreasing skin cancer and the number of sunburns. Although most had not had training on sun protection counseling in their residency program, 6 of 10 indicated that they usually or always counseled about sun protection. Sun protection counseling training in residency programs can potentially extend pediatricians' knowledge of skin cancer and the importance of a broad spectrum of preventive measures, as well as increase their ability to counsel about such measures. PMID- 9369876 TI - Number of sexual partners and health lifestyle of adolescents. Use of the AMA Guidelines for Adolescent Preventive Services to address a basic research question. AB - OBJECTIVE: To expand understanding of the behavioral epidemiology of an important sexually transmitted disease risk factor within a clinical framework of the AMA Guidelines for Adolescent Preventive Services (GAPS): Recommendations and Rationale. DESIGN: Cross-sectional analysis of the fourth year of a longitudinal study of adolescent health behavior. SETTING: High schools in a single major urban school district. PARTICIPANTS: Nine hundred and forty-six white, African American, and Hispanic sexually active adolescents. MAIN OUTCOME MEASURES: Number of sexual partners in previous year and other health-risk and health-protective behaviors. Measures are operationalized according to guidelines for adolescent preventive services recommendations. RESULTS: Adolescents with 3 or more sexual partners annually were more involved with potentially health-harming behaviors such as illicit substance use and less involved with potentially health protective behaviors such as seat belt use. These relationships were independent of sex, ethnic group, or socioeconomic status. CONCLUSIONS: The number of sexual partners may be considered part of a larger pattern of adolescent health-risk and health-protective behaviors. The guidelines may provide a useful framework for clinical assessment of these patterns as part of a routine health care visit of adolescent patients. PMID- 9369877 TI - Maternal expectations about normal child development in 4 cultural groups. AB - OBJECTIVE: To determine whether expectations about normal infant and child development are different among mothers from 4 ethnocultural groups. PARTICIPANTS: Two hundred fifty-five mothers (90 Puerto Rican, 59 African American, 69 European American, 37 West Indian-Caribbean) whose children received health care at hospital-based pediatric clinics and private pediatricians' and family practitioners' offices. DESIGN: Verbally administered questionnaire that included 25 questions in which mothers were asked to give their opinions about the age at which a normal child should begin to accomplish standard developmental milestones. ANALYSIS: Responses (mean ages at which mothers expected children to attain the milestones) from each group were compared after controlling for age of mother, number of children, level of education, and socioeconomic status. RESULTS: Significant differences among ethnic groups' responses were seen for 9 of 25 developmental milestones. Differences were mainly seen among personal and social milestones, and Puerto Rican mothers tended to expect children to attain these milestones at a later age than did other mothers. No differences in responses were seen between Spanish- and English-speaking Puerto Rican mothers. European-American mothers expected children to take first steps and become toilet trained at a later age. CONCLUSIONS: Developmental expectations differ among mothers from different ethnocultural groups. Many of these differences can be explained by underlying cultural beliefs and values and specific child-rearing practices. Clinicians should ask about maternal expectations during child health visits to interpret mothers' concerns and opinions about their children's development. PMID- 9369878 TI - Documenting the educational content of morning report. AB - OBJECTIVES: To document the educational content of a pediatric morning report and to determine if it represents a curriculum. SETTING: A midwestern, tertiary care, pediatric training program. DESIGN: A prospective, observational study was conducted of case presentations discussed during pediatric morning report from July 1995 through July 1996. Presented cases were analyzed for demographics, clinical venues where patients were encountered, case diagnoses, and ensuing discussion. RESULTS: Morning report by study criteria was considered a curriculum. A wide variety of patient ages (aged from birth to 41 years) and all clinical venues were represented. A broad spectrum of diagnoses covered 30 of 31 Pediatrics Review and Education Program (American Academy of Pediatrics, Elk Grove Village, Ill) Content Specification headings and most (72%) of the Educational Objectives listed (N = 977 [72%]). The most common topic areas were infectious diseases (n = 137 [18.2%]), disorders of the blood/neoplasms (n = 85 [11.2%]), neurological disorders (n = 57 [7.5%]), genetics or dysmorphology (n = 56 [7.4%]), and gastrointestinal tract disorders (n = 44 [5.8%]). Top discussion categories were patient clinical presentation (n = 399 [19.6%]), evaluation (n = 375 [18.4%]), and management (n = 377 [18.5%]). CONCLUSIONS: Morning report represents a curriculum in a pediatric residency training program. It can be used effectively to address nontraditional or rarely discussed topics that are important to the overall professional development of pediatric residents. PMID- 9369879 TI - Radiological case of the month. Childhood intervertebral disk calcification. PMID- 9369880 TI - Radiological case of the month. Inguinal hernia presenting as an intestinal obstruction. PMID- 9369881 TI - Picture of the month. Persistent omphalomesenteric duct. PMID- 9369882 TI - Pathological case of the month. Congenital alveolar capillary dysplasia and misalignment of lung vessels. PMID- 9369883 TI - Pathological case of the month. Hereditary fructose intolerance. PMID- 9369884 TI - Bullous impetigo. PMID- 9369886 TI - Composition and concentration of bile acid reflux into the esophagus of patients with gastroesophageal reflux disease. AB - BACKGROUND: Reflux of duodenal contents into the esophagus of patients with gastroesophageal reflux disease has been suggested by pH and bilirubin monitoring but is rarely directly measured. A portable device has been developed and was used to collect and quantitate material refluxed into the esophagus under ambulatory conditions during a prolonged time period. The objective of this study was to use this device to quantitate the composition and concentration of bile acids refluxed into the esophagus of patients with gastroesophageal reflux disease. METHODS: Esophageal aspiration was performed on 43 normal subjects and 37 patients with reflux disease during a 17-hour period. Aspiration was performed through a modified 16F Salem sump tube, positioned 5 cm above the lower esophageal sphincter and connected to a portable, battery powered pump that aspirated continuously at 100 mm Hg pressure. Validation studies showed that minimal amounts of saliva and swallowed liquids were aspirated and that gastric pressure was not altered. Postprandial, upright, and supine collections were performed. Total bile acids were assayed by a standard enzymatic assay; specific conjugated bile acids were analyzed by high-performance liquid chromatography. RESULTS: There was no difference in the total aspiration volume between normal volunteers and patients with gastroesophageal reflux disease, although patients tended to have a higher volume in the supine and postprandial periods. Bile acids could be detected in 58% of normal subjects and 86% of patients (p < 0.003). The mean concentration of bile salt exposure (micromole per liter) was higher in patients during the postprandial and supine periods. The mean bile acid reflux rate (micromole per hour) during all three aspiration periods was significantly higher in patients. On a molar basis the composition of the bile acids was 60% glycocholic acid, 16% glycodeoxycholic acid, and 15% glycochenodeoxycholic acid. Taurocholic, taurodeoxycholic, taurochenodeoxycholic, and glycolithocholic acid constituted the remaining 10%. CONCLUSIONS: Patients with reflux disease have an increased concentration of bile acids in their esophageal aspirates. Most of the exposure occurs during the postprandial and supine periods. A variety of bile acids were detected, most of which were in their glycine conjugated form. PMID- 9369885 TI - Assessment of disseminated pancreatic cancer: a comparison of traditional exploratory laparotomy and radioimmunoguided surgery. AB - BACKGROUND: After curative resection for pancreatic cancer, only 10% of patients survive disease for 5 years. These dismal results suggest the presence of occult tumor at the time of initial operation. This phase I/II study was conducted to compare traditional exploratory laparotomy with radioimmunoguided surgery (RIGS) in the assessment of disseminated pancreatic cancer. METHODS: Ten patients with the diagnosis of adenocarcinoma of the pancreas were injected intravenously with 1 mg CC49 monoclonal antibody radiolabeled with 2 mCi iodine 125. All patients were evaluated by a standard abdominal exploration followed by RIGS. Tumor identified by each technique was documented and categorized as neoplasm disseminated to viscera or lymphatics. RESULTS: There were 25 visceral sites of disease that were traditionally discovered at the time of exploration including pancreas, omentum, small bowel, pelvis, liver, and other. All 25 sites of disease were positive by RIGS plus an additional four sites of visceral tumor for a total of 29 RIGS positive sites of disease. Six lymphatic sites of disease were discovered by traditional examination; however, 44 sites of lymphatic sites were documented by RIGS (p < 0.001). In addition, nine traditionally and pathologically negative/RIGS positive nodes were subjected to cytokeratin and MOC 31 immunohistochemistry. Six of nine nodes were positive by cytokeratin immunohistochemistry, and five of the six cytokeratin positive nodes were MOC 31 positive. CONCLUSIONS: These data suggest that the RIGS technique detected significantly more foci of visceral spread of tumor than traditional exploratory laparotomy and significantly more sites of lymphatic dissemination were identified by RIGS than by standard exploration. PMID- 9369887 TI - Changes in bone mass and serum markers of bone metabolism after parathyroidectomy. AB - BACKGROUND: Primary hyperparathyroidism (PHPT) is associated with an increased bone turnover. The simultaneous use of biochemical and bone mass measurements before and after parathyroidectomy is sparsely reported. This study was carried out to evaluate changes in bone mass and markers of bone metabolism in postmenopausal women with PHPT after parathyroidectomy. METHODS: Twelve women, mean age of 63 years, were investigated. Measurements of bone mineral density (total body, spine, hip, and forearm bone mineral density) with dual-energy x-ray absorptiometry were performed before operation and at follow-up at a median of 23 months. Concomitantly, changes in serum intact parathyroid hormone, bone-specific alkaline phosphatase (B-ALP), osteocalcin, carboxyterminal propeptide of type I procollagen, and the immunoactive carboxyterminal telopeptide of type I collagen were recorded. RESULTS: At follow-up a significant increase in bone mineral density of the spine (p < 0.05), femoral neck (p < 0.05), Ward's triangle (p < 0.05), and trochanter (p < 0.01) was observed. No significant changes in the forearm were registered. Levels of parathyroid hormone, B-ALP, and osteocalcin were elevated and intercorrelated before operation. The serum levels of these parameters decreased significantly after operation. Serum levels of carboxyterminal propeptide of type I procollagen and the immunoactive carboxyterminal telopeptide of type I collagen did not significantly differ from a reference population, and no major changes were observed at follow-up. CONCLUSIONS: Bone mineral density in the spine and hip is improved after parathyroidectomy in postmenopausal women with primary hyperparathyrodism. Serum levels of B-ALP and osteocalcin are elevated in PHPT and decrease after operation. The clinical usefulness of serum markers of collagen metabolism in investigating bone metabolism in PHPT seems limited. PMID- 9369888 TI - Heparin coating of vascular prostheses reduces thromboemboli. AB - BACKGROUND: Synthetic conduits made from currently available materials are suboptimal for use in small-diameter vascular reconstruction because of their high surface thrombogenicity, which leads to failure. METHODS: In this study control, heparin-irrigated, or heparin-bonded expanded polytetrafluoroethylene (ePTFE) grafts (4 mm long by 1 mm inner diameter) were implanted to reconstruct the iliac artery in male rats. The cremaster muscle was isolated as an island flap based on branches of the iliac artery downstream from the graft. Emboli were quantitated by using intravital fluorescent microscopy of the cremaster muscle's microcirculation. RESULTS: The mean number of emboli observed per animal during a 20-minute period was 91 for the control group, 84 for the heparin-irrigated group, and 22 for the tridodecylmethylammonium chloride (TDMAC)-heparin group. The mean area of each embolus was 1057 microns 2 for control, 940 microns 2 for heparin-irrigated, and 808 microns 2 for TDMAC-heparin-coated grafts (p < 0.05 for TDMAC-heparin versus control or heparin-irrigated). CONCLUSIONS: A TDMAC heparin coating of ePTFE microvascular prostheses significantly reduces downstream microemboli. PMID- 9369889 TI - Experimental development of an endoscopic approach to neck exploration and parathyroidectomy. AB - BACKGROUND: Recent advances in minimally invasive surgical technology have the potential to lead to new applications outside body cavities. The purpose of the present study was to develop techniques for obtaining endoscopic exposure and access to the pretracheal space in the neck with the goal of performing neck exploration and parathyroidectomy and to evaluate the safety and efficacy of such an approach experimentally. METHODS: The technique for endoscopic neck exploration was developed in eight adult mongrel dogs and was further evaluated in a survival dog model and in human cadavers. The pretracheal space was accessed by a 2.5 cm midline incision in the lower neck. This space was expanded with a balloon dissector, and exposure was maintained with an external lift device. A 5 or 10/12 mm midline port and two to four lateral 5 mm cervical ports were placed, and dissection was carried out with pediatric endoscopic instruments and an ultrasonic coagulator. Excised parathyroid tissue was verified histologically. RESULTS: Two-gland parathyroidectomy was successfully completed in five of six dogs; inadequate exposure led to a failed procedure in one animal. Mean operative time was 130 +/- 6 minutes, and there were no operative complications. Serum calcium levels did not change significantly after operation (p = not significant). At autopsy, approximately 20 ml of clear sterile fluid was present in the pretracheal space of every dog. In five human cadavers mean dissection time for attempted four-gland parathyroidectomy was 69 +/- 38 minutes (range, 45 to 135 minutes). Four of four parathyroids were identified and removed in two patients, three of three parathyroids in one patient, three of four parathyroids in one patient, and two of four parathyroids in one patient. CONCLUSIONS: Parathyroidectomy may be performed safely and reliably in an animal model with minimally invasive techniques that can be applied to parathyroid dissection in human cadavers. These results suggest that an endoscopic approach to neck exploration and parathyroidectomy is potentially feasible and may warrant further study in clinical trials. PMID- 9369890 TI - Influence of continuous hemofiltration on the hemodynamics of trauma patients. AB - BACKGROUND: The aim of this prospective randomized controlled study was to investigate the effects of continuous venovenous hemofiltration on the hemodynamics and respiratory function of critically ill trauma patients with multiple organ dysfunction syndrome. METHODS: Thirty consecutive critically ill, mechanically ventilated, trauma patients with multiple organ dysfunction syndrome (without kidney failure) who had invasive hemodynamic monitoring for management of hypotension or hypoxemia were randomized to treatment with or without continuous venovenous hemofiltration. Hemodynamics profile was recorded immediately before and at 6, 12, 24, and 48 hours after the hemofiltration was started (mean of three set data each time). No changes in ventilatory parameters were performed during the study. RESULTS: Thirty patients were analyzed (15 with and 15 without hemofiltration). Both groups were similar in age (36 +/- 18 versus 36 +/- 14 years) and severity scores (Injury Severity Score, 32 +/- 16 versus 30 +/- 11; Acute Physiology and Chronic Health Evaluation II score, 22 +/- 7 versus 21 +/- 6; Goris score, 5.2 +/- 1.7 versus 5.2 +/- 1.8) and received similar inotropic support. We found a significant improvement in mean arterial pressure (80 +/- 9 to 94 +/- 8 (mm Hg), p = 0.01) and partial pressure of oxygen in arterial blood/inspiratory oxygen supply index (124 +/- 40 to 204 +/- 44, p = 0.03) in the intervention group during the study period. We did not find any other significant change in variables studied. CONCLUSIONS: Continuous venovenous hemofiltration is associated with a significant improvement in hemodynamic and respiratory variables in critically ill trauma patients with multiple organ dysfunction syndrome. This improvement can help in the management of these patients. Further work is necessary to define whether this technique can reduce the high mortality of this disease. PMID- 9369891 TI - Early complement system activation and neutrophil priming in acute pancreatitis: participation of trypsin. AB - BACKGROUND: It is known that the pancreatic enzyme trypsin can cleave components of the complement system, producing the chemokines C3a and C5a. In the setting of experimental acute pancreatitis, we analyzed the contribution of serum trypsin to systemic complement activation and its importance in neutrophil lung sequestration, an early event in acute pancreatitis. METHODS: Cerulein was infused into Lewis rats to produce mild edematous acute pancreatitis. Soluble complement receptor, sCR1, was used to block complement activation. RESULTS: Induction of acute pancreatitis was confirmed by the serum levels of amylase and trypsin and by histologic studies. A correlation was found between serum total complement activity and the trypsin level (r = -0.884). Whole lung tissue myeloperoxidase activity was high in rat lungs at t = 4 hours, indicating accumulation of neutrophils. The sCR-1-treated group showed significantly lower levels. Flow cytometry of neutrophils incubated with serum from rats with pancreatitis showed significantly higher CD11b/CD18 expression than that after incubation with serum from control or sCR-1-treated rats. Until t = 12 hours, no change in the lung wet to dry weight ratio or bronchoalveolar fluid cytology was observed, indicating no functional enhancement of neutrophils that had accumulated in the lungs. CONCLUSIONS: The present results demonstrate the important role of trypsin in systemic complement activation early in the course of acute pancreatitis. The resulting central production of chemotaxins causes priming of circulating neutrophils and subsequent lung sequestration. These events can be at least partially reversed by sCR-1 treatment. PMID- 9369892 TI - Neutrophil activation, vascular leak toxicity, and cytolysis during interleukin-2 infusion in human cancer. AB - BACKGROUND: Recombinant interleukin-2 (rIL-2) therapy for advanced malignancy is usually associated with a vascular leak syndrome (VLS) similar to that seen in severe sepsis. We investigated the possibility that the IL-2-induced VLS may be associated with the presence of circulating activated polymorphonuclear (PMN) leukocytes as occurs in sepsis syndrome. METHODS: Estimation of phenotypic (CD11B/CD18) and functional (H2O2, HOCl) up-regulation of circulating neutrophil activity was made by fluorescence-activated cell sorter analysis and ultraviolet spectrophotometry. Associated systemic cytokine enhancement tumor necrosis factor alpha by enzyme-linked immunosorbent assay for bioactivity and parallel estimation of clinical evidence of vascular leak syndrome were also studied in human subjects with advanced cancer receiving therapeutic doses of rIL-2. RESULTS: The present studies confirm previous reports that tumor necrosis factor alpha is released into the circulation during infusional therapy with rIL-2. In addition, we have found that this is accompanied by both phenotypic (up regulation of CD11b/CD18 adhesion receptor expression) and functional (hydrogen peroxide and hypochlorous acid production) evidence of potent PMN activation. Furthermore, patients showing disease response to treatment have significantly greater production of PMN oxidants. CONCLUSIONS: These data suggest that the VLS seen during rIL-2 infusion in human beings may be attributable to PMN mechanisms similar to those invoked during severe sepsis. Consequently, this study may provide further insights into the mechanism of rIL-2's therapeutic action in advanced malignant disease. PMID- 9369893 TI - Cell cycle-mediated regulation of hepatic regeneration. AB - BACKGROUND: Hepatic regeneration after partial hepatectomy (PH) is characterized by a synchronous induction of normally quiescent hepatocytes to reenter the cell cycle, leading to a complete restoration of hepatic mass. Cell cycle progression requires activation of cyclin-dependent kinases (Cdks) that are regulated by cyclins and Cdk inhibitors. METHODS: Protein expression of the cyclins (D-type and E), Cdks (Cdk2 and 4), and Cdk inhibitors (p21 and p27) was measured by Western blot after SHAM operation or PH in F344 rats. In addition, Cdk2 associated kinase activity was measured. RESULTS: Rapid induction of D-type and E cyclins, as well as their catalytic partners, Cdk2 and Cdk4, occurred after PH in rats. Complexes containing cyclin E and Cdk2 assembled in the regenerating liver, leading to increased Cdk2-associated kinase activity. The regenerating liver returned to preresection weight by day 7, at which time the Cdk2 activity also returned to SHAM levels. Biphasic induction of the Cdk inhibitor p21 was observed; the first peak occurred as early as 6 hours after PH, with a subsequent peak in expression occurring at 24 to 72 hours after PH. CONCLUSIONS: Taken together, these data support the concept that cyclins, Cdks, and Cdk inhibitors regulate cell cycle progression in the regenerating liver. In addition, the induction of p21 at two time points suggests that this protein may regulate both early proliferation and subsequent inhibition of hepatocyte regeneration. PMID- 9369895 TI - Changes in measured resting energy expenditure after Roux-en-Y gastric bypass for clinically severe obesity. AB - BACKGROUND: Roux-en-Y gastric bypass (RYGB) results in sustained weight loss and amelioration of comorbid conditions in patients with clinically severe obesity. The mechanism of weight loss after RYGB is not well defined. The objective of this study was to document the changes in measured resting energy expenditure (MREE) over time in patients with clinically severe obesity after RYGB. METHODS: We prospectively studied MREE in 70 patients (11 male, 59 female; body mass index [BMI], 40 to 80 kg/m2) treated by RYGB. MREE was measured by indirect calorimetry before operation and at 6 weeks and 3, 6, 12, 18, and 24 months after operation. Patients were stratified to hypometabolic ([HM] MREE less than 85% of Harris Benedict [HB] predicted; n = 22) or normal metabolic rate ([NM] MREE +/- 15% HB predicted; n = 48) before operation; mean BMIs were HM, 53.4 +/- 11.0 kg/m2; NM, 51.4 +/- 9.8 kg/m2; p = not significant. MREE, weight loss, percent excess body weight loss (EWL), and energy intake were determined at each time point. RESULTS: Overall, MREE was significantly less than HB-predicted REE before operation (90 +/- 28%), but rose to become equal to the HB-predicted REE by 6 weeks (96 +/- 15%) and remained so. When stratified by initial metabolic rate, MREE increased significantly in the HM patients by 6 weeks, from 1329 +/- 604 kcal/day (55% of HB predicted) to 1882 +/- 398 kcal/day (88% of HB predicted) (p < 0.001), and MREE remained normal (2332 +/- 484 kcal/day to 2029 +/- 410 kcal/day) in the NM patients. Percent EWL was similar in both groups at each time. Energy intake was 2603 +/- 982 kcal/day before operation and fell to 815 +/- 196 kcal/day at 3 months, 969 +/- 241 kcal/day at 6 months, 1095 +/- 307 kcal/day at 12 months, 1259 +/- 466 kcal/day at 18 months, and 1373 +/- 620 kcal/day at 24 months, and was similar between the groups at each time point. Percent HB-predicted REE increased significantly after operation despite a significant decrease in energy intake. CONCLUSIONS: RYGB is associated with significant changes in MREE over time. In NM patients MREE fell over time consistent with weight loss but remained normal, whereas patients who were hypometabolic exhibited increases in MREE toward normal. These changes in MREE occurred despite reduced energy intake comparable to a very low calorie diet. This paradoxical effect on MREE may contribute to the enhanced weight loss associated with RYGB. PMID- 9369894 TI - Overexpression of endothelin-1 mRNA and protein in portal hypertensive gastric mucosa of rats: a key to increased susceptibility to damage? AB - BACKGROUND: Portal hypertension predisposes gastric mucosa to increased injury by various noxious factors. Because endothelin-1 (ET-1) is a potent vasoconstrictor that enhances gastric mucosal injury, we examined ET-1 expression in the portal hypertensive (PHT) gastric mucosa and its possible role in increased mucosal susceptibility to damage. METHODS: In gastric specimens of PHT or sham-operated rats, ET-1 mRNA expression was studied by S1-nuclease protection assay and ET-1 protein by enzyme immunoassay and immunostaining. We also determined the extent of ethanol-induced gastric mucosal necrosis in PHT and sham-operated rats after administering either a placebo or FR 139317, a selective ETA receptor antagonist. RESULTS: In PHT stomachs ET-1 mRNA expression and protein concentration were significantly increased compared with sham-operated controls: mRNA expression (ET 1/glyceraldehyde-3-phosphate-dehydrogenase ratio), 0.54 +/- 0.18 versus 0.30 +/- 0.08; protein concentration, 7.36 +/- 2.21 pg/mg versus 3.93 +/- 0.40 pg/mg, respectively; both p < 0.01. Immunofluorescence signal of ET-1 protein was predominantly localized to endothelia of gastric mucosal and submucosal vessels. In PHT stomachs FR 139317 significantly reduced mucosal necrosis (percentage of necrotic area, from 24.9 +/- 5.9% to 10.8 +/- 4.0%; p < 0.01), although it had no effect on sham-operated controls. CONCLUSIONS: Portal hypertension activates the ET-1 gene with overexpression of ET-1 protein in the gastric mucosa. Protection of PHT gastric mucosa by ETA receptor antagonist against damage indicates that overexpression of ET-1 plays an important role in increased susceptibility of PHT gastric mucosa to injury. PMID- 9369896 TI - Adaptive lipid metabolism after ileal autotransplantation in pigs with proximal gut resection. AB - BACKGROUND: Transplantation of the small intestine impairs intestinal absorptive function, but the adaptive response of a segmental graft is unknown. The aim of this study was to investigate the effects of ileal autotransplantation on the adaptive absorption and metabolism of lipids in pigs that had undergone proximal gut resection. METHODS: Serum lipids, plasma vitamins A and E, absorption and excretion of cholesterol, bile acids and fat, plasma cholesterol precursor and plant sterol proportions to cholesterol (respective markers of cholesterol synthesis and absorption), enteric structure, and transit were determined 4, 8, and 14 weeks after 75% proximal resection with (n = 15) or without (n = 15) autotransplantation of the remaining ileum. RESULTS: As compared with pigs that underwent proximal gut resection, the additional autotransplantation reduced the adaptive increase in total serum and high-density lipoprotein cholesterol, plasma plant sterol proportions and vitamin E concentrations, cholesterol and fat absorption efficiency, and villus height (p < 0.05 for all) during the 14 postoperative weeks and resulted in increases of up to 4.6, 2.7, 1.3, and 2.1 times the plasma cholesterol precursors (p < 0.005), fecal excretion of bile acids (p < 0.0005), neutral steroids (p < 0.005), and net elimination of cholesterol (p < 0.0005), respectively. Cholesterol and fat absorption and plasma plant sterols were significantly enhanced between 8 and 14 weeks after autotransplantation (p < 0.05, p < 0.005, and p < 0.05, respectively), whereas fecal elimination of cholesterol remained increased until the end of the follow up. CONCLUSIONS: Autotransplantation of the ileum in pigs that have undergone proximal small bowel resection disturbs the adaptive absorption of cholesterol, bile acids, fat, and fat-soluble vitamins, resulting, through increased fecal elimination of cholesterol, in decreased serum cholesterol despite a marked compensatory increase in cholesterol synthesis. PMID- 9369897 TI - A case of Kikuchi's disease with abdominal manifestations. PMID- 9369898 TI - Application of self-expandable metallic stents in the inferior vena cava followed by portosystemic shunt in the treatment of primary Budd-Chiari syndrome complicated by caval obstruction. PMID- 9369899 TI - Necrotizing mastopathy caused by calciphylaxis: a case report. PMID- 9369900 TI - Aggressive angiomyxoma presenting as a pelvic floor hernia. PMID- 9369901 TI - Techniques of preserving the spleen with distal pancreatectomy. PMID- 9369902 TI - Gut as a possible source for endotoxemia. PMID- 9369903 TI - Feasibility of high-volume intestinal lavage in critically ill patients. PMID- 9369904 TI - Treatment of small bowel obstruction by jejunal enterolith. PMID- 9369905 TI - [Treatment based on biological characteristics of lung cancer: biological differences between small cell and non-small cell lung cancer and gene therapy]. AB - Whether chemotherapy or surgical resection is primarily selected for lung cancer therapy is determined based on the pathological diagnosis of small cell or non small cell lung cancer. In future, however, each standard therapy should be established against the respective subgroups of lung cancer, which will be more precisely defined depending on the biological or the molecular basis, like malignant lymphoma. Much evidence is increasing to help understand the mechanisms mediating differences in clinical behavior and neuroendocrine features between small cell and non-small cell lung cancer. Here we showed the experimental models of tissue-specific gene therapy targeting CEA- or Myc-overexpressing lung cancer cell lines. PMID- 9369906 TI - [Genetic alteration of lung cancer as a prognostic marker and its therapeutic implications]. AB - Many genetic lesions found in non-small cell lung cancer (NSCLC) have been reported to be associated with a poor prognostic outcome of this disease. Such alterations include mutations of ras genes, overexpression of myc or erbB2 genes and inactivation of RB genes. Among them, the prognostic implications of the p53 gene have been most extensively studied; over 20 reports have been published. However, the significance of the p53 gene abnormality also still remains unclear. Therefore, we re-evaluated our 562 patients with NSCLC retrospectively to see if the p53 gene abnormality really had an effect on patients' survival in this large cohort. There was no effect of p53 gene abnormality on all patients with NSCLC or on those with squamous cell carcinoma, but p53 abnormality was a significant, independent prognostic marker in adenocarcinoma subset. We should plan a clinical trial of postoperative adjuvant therapy for patient with pulmonary adenocarcinoma incorporating information on the p53 gene status to possibly translate these findings into clinical practice. PMID- 9369907 TI - [The role of CT and MR imaging in the diagnosis of lung cancer]. AB - CT and MR imaging can play an important role in the diagnosis of lung cancer. Evaluation of a solitary pulmonary nodule is usually carried out using CT. High resolution CT is useful in the morphologic diagnosis of a solitary pulmonary nodule. The enhancement characteristics of a pulmonary nodule in contrast enhancement CT can be a method of distinguishing benign and malignant nodules. MR imaging is superior to CT in contrast resolution and multidirectional imaging capability. Contrast-enhancement MR imaging can describe the enhancement characteristics of the pulmonary lesion better than contrast-enhancement CT. The extent of chest wall and mediastinal invasion of lung cancer can be better shown using MR imaging than CT. PMID- 9369908 TI - [Principles of histological diagnosis and clinical staging evaluation for lung cancer]. AB - In the histological diagnosis, it is important to consider the presence of borderline lesions, the possibilities of multiple primary lung cancers and the differential diagnosis between small cell carcinoma and non-small cell carcinomas. In the definite diagnosis, moreover, it is necessary to refer to the special staining procedures, including immuno-histochemistry. In clinical trials, one must evaluate the precise clinical staging in addition to the pathological qualification for enrolled cases. On the other hand, the staging evaluation should be minimal in the practical treatment. It should be noticed that the staging procedure between non-small cell carcinoma and small cell carcinoma is different. PMID- 9369909 TI - [State of the art treatment of lung cancer: non-small cell lung cancer--surgical treatment]. AB - Surgery is defined as purely a local treatment modality. In the treatment of non small cell lung cancer, surgery remains the first-line treatment of choice for local diseases. Thus, stages I, II, and a part of IIIA disease are definite indications for surgical therapy. The standard operative mode in curative intent for such local diseases is the resection of the entire lobe or lung where the cancer is located. The prognostic significance of hilar/mediastinal lymph node dissection remains controversial, although it can provide the most accurate information regarding the metastatic status of hilum and mediastinum. For locally advanced diseases of stages IIIA and IIIB, the surgical approach still remains investigational in a combined modality setting. For N2 diseases (with mediastinal node metastasis), the prognostic benefit of both preoperative and postoperative chemo (-radio) therapy has not been definitively demonstrated yet, although several reports suggested their potential benefits. They await further evaluation by clinical trials in a phase III setting. Although aggressive surgical approaches for tumors invading surrounding vital structures (IIIB disease) have been reported, it is also still uncertain whether their results can really exceed those obtained by chemoradiotherapy. PMID- 9369910 TI - [The state of the art: radiation therapy for non-small cell lung cancer]. AB - The standard radiation schedule for non-small cell lung cancer is conventional fractionated 60-70 Gy/6-7 weeks in Japan, while a split-course or hypofractionated schedule is also used in some institutions in other countries. Hyperfractionated radiotherapy with/without chemotherapy is increasing while no definitive treatment schedule has been established as a standard treatment method. Dose escalation study by 3D-conformal radiotherapy is also an attempt at a breakthrough of radiotherapy in unresectable non-small cell lung cancer. PMID- 9369911 TI - [Combination chemotherapy in the treatment of inoperable non-small cell lung cancer]. AB - Recent meta-analysis data showed that alkylating agents had a detrimental effect on survival of patients with non-small cell lung cancer (NSCLC), but that cisplatin-containing regimens afforded a modest but significant survival advantage. Regrettably, there is no standard therapy for the treatment of NSCLC. The development of new drugs is clearly an important avenue for improving the treatment of NSCLC. Several cytotoxic agents with promising single-agent activity, including vinorelbine, irinotecan, paclitaxel, docetaxel, and gemcitabine have recently been defined. The data on combination chemotherapy of new agents in the treatment of advanced NSCLC is then reviewed here. PMID- 9369912 TI - [Combined modality treatment of chemotherapy and radiotherapy for unresectable non-small cell lung cancer]. AB - Unresectable stage III non-small cell lung cancer (NSCLC) comprised a heterogeneous group. According to the policy of evidence-based medicine, the literature on combined modality treatment of chemotherapy and radiotherapy for unresectable non-small cell lung cancer was reviewed. Several prospective randomized trials demonstrate a survival advantage to combined modality treatment over radiotherapy or chemotherapy alone when a cisplatin-based chemotherapy regimen is utilized in the treatment plan. Combined modality treatment of cisplatin-based chemotherapy and radiotherapy is standard treatment for patients who met eligibility criteria of clinical trials. It is suggested that concurrent chemotherapy and radiotherapy is more efficacious in terms of response rate and survival than chemotherapy followed by radiotherapy. Determining the contribution of new agents in combined modality treatment will require carefully designed and conducted clinical trials. PMID- 9369913 TI - [Surgical treatment for small cell lung cancer]. AB - Results of surgical treatment for small cell lung cancer were reviewed to confirm the role of surgery. Most of the surgical therapy was performed with post or pre operative chemotherapy. Clinical staging of small cell lung cancer treated by chemotherapy and/or radiotherapy has not been classified according to the TNM staging system, which made it difficult to compare the results of surgical treatment with non-surgical treatment in detail. Results of surgical treatment for small cell lung cancer according to the TNM staging system reported in 1990's were as follows. For stage I diseases, nearly all the patients underwent complete resection followed by standard chemotherapy. Five-year survival rates were over 50% in most of the reports. Surgical resection followed by chemotherapy is the standard therapy for stage I diseases. For stage II diseases, the greater part of patients were treated by complete resection followed by chemotherapy, which resulted in five-year survival rates of 28-35%. Nationwide statistics on surgical resection for small cell lung cancer in Japan revealed that the stage I and II diseases are actually resected, and the five-year survival rate reached 37%. Thus, surgery followed by chemotherapy for stage II diseases is becoming the standard therapy. For stage IIIA diseases, surgical resection after chemotherapy followed by chemotherapy and/or radiotherapy has been tried investigationally. The five-year survival rates of 16-48% in these patients suggests the increasing role of surgery for these patients. PMID- 9369914 TI - ["State-of-the-art" chemotherapy for small-cell lung cancer]. AB - A combination of etoposide and cisplatin (EP) is the current standard chemotherapy for small-cell lung cancer (SCLC). A combined modality-treatment of EP and thoracic irradiation has been established as the standard therapy for limited disease (LD)-SCLC. To improve further the results of treatment for SCLC, it is necessary to reconsider a new non-cross resistant alternating chemotherapy including promising new agents in LD-SCLC. A new maintenance chemotherapy with new agents should also be studied again. In extensive disease (ED)-SCLC, there were few long-term survivors in spite of aggressive chemotherapy. It is important to develop a new combination chemotherapy including new agents (irinotecan, topotecan, paclitaxel, docetaxel, and gemcitabine). PMID- 9369915 TI - [Multimodality therapy for small-cell lung cancer]. AB - In limited small-cell lung cancer, combined chemoradiotherapy is superior to chemotherapy alone. Early thoracic radiotherapy (TRT) yields superior rates of long-term survival than delayed TRT. Concurrent use of TRT with cisplatin and etoposide may be optimal and has been considered the standard in North America and Japan. The use of multimodality therapy in LD-SCLC appears to have substantially improved median (> 20 mos) and 3-year survival rates (> 40%). The development of more effective local and systemic therapy is necessary for cure oriented treatment. PMID- 9369916 TI - [Prophylactic cranial irradiation in small cell lung cancer]. AB - The Brain is one of the common relapse sites in small cell lung cancer because of isolation from chemotherapeutic agents by the blood-brain barrier. Prophylactic cranial irradiation (PCI) is expected to reduce brain relapse and increase the survival rate. PCI prolonged the survival in only 10-20% of patients with small cell lung cancer after complete response. Most randomized trials demonstrated the significant reduction of brain relapse, however, none of them demonstrated an increase of survival rate because their sample sizes were relatively small to detect the difference of survival, such as 10% in 3-year survival. The results of ongoing meta-analysis should provide new findings on the survival benefits of PCI. No standard PCI dose and schedule are established, however, over 30Gy for total dose, over 3Gy per fraction. Concurrent use with chemotherapy is considered to induce central nerve toxicity. PCI should be proposed for patients with complete response as an optional treatment. PMID- 9369917 TI - [State of the art: treatment of malignant pleural and pericardial effusions]. AB - Symptomatic malignant pleural effusions should be treated systemic chemotherapy in chemo-sensitive tumors such as small cell lung cancer, breast cancer, lymphoma, or ovarian cancer. In other non-chemo-sensitive malignancies including non-small cell lung cancer, water-sealed tube drainage and pleurodesis is the standard treatment of choice in most of the cases. Drugs for instillation should be blomycin or OK-432 if commercially available. Instead of the former standard drug tetracycline, doxycycline has been frequently used. As we have no randomized trials, this drug awaits phase III trials. Talc slurry has been accepted and counted as one of the standard choices in the western countries, however, it usually needs general anesthesia and adverse effects are not negligible. As we have little experience on this modality, it should not be considered as a standard treatment. Other antitumor drugs instillation, thoraco-abdominal shunting, and pleuro-pneumonectomy should be considered experimental because of the lack of randomized trials. Symptomatic pericardial malignant effusion or cardiac tamponade is an oncologic emergency. We had better to treat the patient immediately by pericardiocentesis under the cardiac echographic guidance. It should be reserved to solve in randomized trials that the best method would be pericardiocentesis alone, percutaneous continuous drainage, pericardial fenestration, or pericardio-thoraco fenestration. Instillation of drug like doxycycline, OK-432, or bleomycin, lacks phase III comparison and it should be categorized as experimental. PMID- 9369918 TI - [Treatment for brain metastases of lung cancer]. AB - Treatment for brain metastases of lung cancer was reviewed. For single brain metastasis of non-small cell lung cancer, surgical resection followed by whole brain irradiation (WBI) or stereotactic radiosurgery (SRS) showed a better treatment outcome compared with WBI alone. A randomized trial comparing surgical resection plus WBI with SRS may be warranted. For multiple brain metastasis, WBI is now the sole effective therapy. However, an optimal schedule of radiotherapy has not yet been established. For brain metastasis of small-cell lung cancer (SCLC), rapid improvement of symptoms is achieved with WBI, while the response duration is brief. Recently, the brain metastasis from SCLC is suggested to respond as well to the systemic chemotherapy as does extracranial disease, even though it has not been documented in randomized trials. Consolidating WBI after systemic chemotherapy for the brain metastasis from SCLC should be evaluated. PMID- 9369919 TI - [Strategy of therapy for interstitial lung disease due to chemotherapeutic drugs or radiation]. AB - Pulmonary disease induced by chemotherapeutic drug or radiation is one of the major cause, of death in patients with lung cancer. Many of these patients die from interstitial lung disease despite discontinuation of the drug and addition of corticosteroid treatment. The clinical presentation is similar for all of the chemotherapeutic drugs. For the early detection of interstitial lung disease due to a chemotherapeutic drug, serial measurements of the CO diffusing capacity (DLco), serum LDH, and serum KL-6 are useful. The first step in treatment is withdrawal of the drugs, and pulse therapy by using methylprednisolone is used as a standard therapy for interstitial lung disease due to chemotherapeutic agents. Immunosuppressive agents, such as cyclophosphamide or azathioprine, might be used as second-line drugs in patients for whom drugs either failed or could not tolerate corticosteroid treatment. Thus the usefulness of this therapy is unknown, and it should be considered as a marginal therapy. To develop an investigational therapy for the chemotherapeutic drug-induced interstitial lung disease, we investigated the efficacy of a new specific neutrophil elastase inhibitor (ONO-5046.Na) in bleomycin-induced pulmonary fibrosis. The inhibitory effect of ONO-5046.Na was observed in bleomycin-induced pulmonary fibrosis in mice. This specific neutrophil elastase could be a investigational therapeutic agent for interstitial lung disease due to chemotherapeutic agents used against lung cancer. PMID- 9369920 TI - [Problems and recommendations for use of G-CSF in lung cancer patients with neutropenia after chemotherapy]. AB - Reports are reviewed on G-CSF studies in neutropenia after lung cancer chemotherapy, especially randomized trials including our data. With preventive administration of G-CSF after dose-intensive chemotherapy in small-cell lung cancer, three studies showed that G-CSF shortened the duration of neutropenia, and reduced the incidence of neutropenic fever, the use of antibiotics and hospitalization with statistical significance, but showed no advantage in response rate or the incidence of infection-related death. And the effect on survival has not been proved clearly. When G-CSF was administered to afebrile neutropenic patients, it accelerated recovery from neutropenia significantly, but did not clearly reduce the incidence of neutropenic fever or infection. When G CSF was administered to febrile neutropenic patients combined with antibiotics concurrently, it also could accelerate recovery of neutropenia significantly, but could not reduce neutropenic fever or infection compared with no CSF. For optimal use, it has not been proved when G-CSF should be started. Marginal therapy is considered to be administration in neutropenia with fever or infection and in severe neutropenia. Investigational therapy is considered for administration in neutropenia without fever or infection and use in clinical trials. Because no standard therapy with G-CSF has been established, additional clinical trials are necessary. PMID- 9369922 TI - [International consensus for lung cancer treatment]. AB - Lung cancer is classified into small cell lung cancer (SCLC) and non-SCLC (NSCLC) based on their clinical and biological characteristics. Chemotherapy is currently a primary treatment modality for SCLC, which is divided into two groups: limited and extensive stage. In the limited stage, radiotherapy is added to chemotherapy to improve the treatment result. In the extensive stage, only chemotherapy provides a survival benefit. In NSCLC, surgical resection is a main treatment modality in stage I, II, and some stage III patients. Other unresectable patients are treated by cisplatin-based chemotherapy and/or radiotherapy with limited benefit. Most of lung cancer patients need systemic therapy, so chemotherapy is important for its treatment. However, the agents which are commonly used for treatment of lung cancer are not sufficiently beneficial. Further improvement, including development of new anti-cancer agents, is expected. PMID- 9369921 TI - [Paraneoplastic syndrome]. AB - Treatment for the paraneoplastic syndrome associated with lung cancer was reviewed. The principle of the treatment of paraneoplastic syndrome is to control cancer as an underlying disease. Therefore, the standard therapy for Cushing's syndrome associated with lung cancer is surgical treatment if the tumor is operable. There is no standard therapy for Cushing's syndrome associated with advanced small-cell lung cancer. Metyrapone is used in combination with systemic chemotherapy. The effects of ketoconazole and octreotide are under investigation. To control hyponatremia due to the syndrome of inappropriate antidiuretic hormone secretion, fluid restriction is standard. When hyponatremia cannot be controlled with fluid restriction, demeclocycline can be used. For life-threatening hyponatremia, hypertonic saline with intravenous furosemide is administered under careful monitoring. Followed by hydration with saline, pamidronate is effective for the control of symptomatic hypercalcemia. Combined use of calcitonin facilitates rapid normalization of serum calcium for critically ill cases. Heparin is used for patients with recurrent episodes of thrombosis resulting from chronic disseminated intravascular coagulation, although the efficacy is controversial. Thrombocytes and coagulation factors are combined with heparin for patients with uncontrollable bleeding, although the efficacy is not established. PMID- 9369923 TI - Telomerase and cancer. PMID- 9369924 TI - Nucleotide sequence variation of human T-lymphotropic virus type II in Vietnam. AB - A high rate of human T-lymphotropic virus type II (HTLV-II) infection has been documented in intravenous drug abusers (IVDAs) in South Vietnam. We have investigated the molecular characteristics of the virus and have shown that one HTLV-II subtype is predominant in Ho Chi Minh City. This molecular subtype, HTLV IIb, was identified in a number of South Vietnamese by nucleotide sequence analysis of the long terminal repeat (LTR) region. HTLV-IIa was not found. These findings suggest that HTLV-IIb is endemic in IVDAs in South Vietnam, although IVDAs in urban areas in North America are predominantly infected with HTLV-IIa. PMID- 9369925 TI - Assessment of preference for breast cancer chemoprevention in Japanese young women. AB - Pills containing estrogen and progesterone or gonadotropin releasing hormone agonist have been considered valuable to prevent breast cancer. This study assessed preference for the combination-type pill for preventing breast cancer, to evaluate the hypothetical preventive effect of this agent among young Japanese women. The standard gamble method was applied. Fifty-five college students and 44 nursing school students aged between 18 and 41 years were asked to decide the probability of being affected by breast cancer at which they would start to take this agent. Preference score was calculated by subtracting the probability given by each respondent from 1, which corresponds to the value (utility) she allotted to the agent. The means of preference score were 0.58, 0.48, 0.37, and 0.27 for 100, 75, 50, and 25% of efficacy levels of the agent, respectively. Preference score was significantly lower in nursing school students and those whose knowledge about hormones were relatively high. Score of Health Locus of Control (HLC) was nonsignificantly negatively correlated with preference score at any efficacy level. HLC score was significantly higher among those who refused the agent with 50 and 25% efficacy levels at 100% level of breast cancer risk. The data suggest that perceived risk of this agent was not negligibly small in this population and school status, knowledge about hormones, and beliefs about health would affect preference for the agent. Understanding of preference for chemopreventive agents for breast cancer, especially those containing hormones, is important to assess their potential as future preventive agents and is helpful when planning a strategy of chemoprevention. PMID- 9369926 TI - Carcinogenicity of methylurea or morpholine in combination with sodium nitrite in rat multi-organ carcinogenesis bioassay. AB - For carcinogenic risk assessment of combinations of N-nitroso precursors in man, the effects of feeding methylurea (MU) or morpholine (Mor) plus sodium nitrite (NaNO2) were investigated using a multi-organ carcinogenesis model. In experiment 1, to initiate multiple organs, groups of 10 or 20 male F344 rats were treated with 6 carcinogens targeting different organs. Starting a week after completion of this initiation phase, animals were given 0.1% MU or 0.5% Mor in their food and/or 0.15% NaNO2 in their drinking water for 23 weeks. The induction of tumors and/or preneoplastic lesions in the forestomach and esophagus was significantly increased in the group receiving MU plus NaNO2. The numbers and areas of liver glutathione S-transferase placental form (GST-P)-positive foci were significantly elevated with MU or Mor plus NaNO2. Experiment 2 was conducted to assess formation of N-nitroso compounds in the stomach, and to detect DNA adduct generation in target organs by immunohistochemical staining. Groups of 5 or 14 animals were starved overnight, then given 0.4% MU or 2.0% Mor in the diet, or basal diet alone for 1 h. Then NaNO2 or distilled water was given intragastrically. The mean gastric N-methyl-N-nitrosourea yield in the MU plus NaNO2 group was 7700 micrograms at 2 h after combined administration. The mean N nitrosomorpholine yield in the group given Mor plus NaNO2 was 6720 micrograms. Immunohistochemically, N7-methyldeoxyguanosine-positive nuclei were evident in the forestomach epithelium at 8 h after the combination treatment with MU plus NaNO2. PMID- 9369927 TI - Relationship between the nature of mucus and crypt multiplicity in aberrant crypt foci in the rat colon. AB - Aberrant crypt foci (ACF) induced in the distal colon of F344 male rats, 4, 8, 12 and 35 weeks after the first administration of 1, 2-dimethylhydrazine-2HCl (DMH) were examined to determine whether a correlation exists between the nature of goblet cell mucin and the number of crypts (crypt multiplicity) comprising the ACF. According to the ACF score calculated from the results of the qualitative observation of sulfomucins (SuMs) and sialomucins (SiMs), the ACF in the 4th week showed a weak correlation between the nature of the mucus and crypt multiplicity, and the ACF of each class showed similar mucous profiles. From the 8th week, a significant difference (P < 0.01) was recognized between the ACF consisting of 3 crypts or less and those consisting of 4 crypts or more. The proportion of crypts with SiM predominance showed a decrease in the 8th week in the ACF consisting of 1 crypt and in the 12th week in the ACF consisting of 2 or 3 crypts, implying a recovery tendency. The ACF consisting of more than 4 crypts showed little change over time, retaining the tendency of SiM predominance. Ulex europaeus agglutinin I (UEA-I) lectin-positive crypts appeared in the ACF. This finding was significantly more prominent (P < 0.001) in the ACF with SiM predominance than in the ACF with SuM predominance at each experimental period, and in the 12th week after the first administration of DMH, the incidence of ACF with UEA-I-reactive mucin was decreased in the ACF groups consisting of 3 crypts or less, compared with the ACF groups consisting of 4 or more crypts. These results suggest that the biological quality of mucus in ACF consisting of 4 or more crypts is different from that in ACF consisting of 3 crypts or less. This difference should be considered when ACF are used as an intermediate biomarker of colon cancer. PMID- 9369928 TI - Regressive effects of various chemopreventive agents on azoxymethane-induced aberrant crypt foci in the rat colon. AB - Regressive effects of four chemopreventive agents [5-hydroxy-4-(2-phenyl-(E) ethenyl)-2(5H)-furanone (KYN-54), S-methyl methanethiosulfonate (MMTS), chlorogenic acid (CA), and piroxicam] on azoxymethane (AOM)-induced aberrant crypt foci (ACF) in the colon of male F344 rats were examined by dietary exposure. At six weeks of age, 60 rats of groups 1 through 5 received subcutaneous injections of AOM (15 mg/kg body weight) once a weeks. Twelve weeks after the first carcinogen injection, when the occurrence of ACF was maximal, the rats in groups 2 through 5 were started on diet containing the test chemicals as follows: group 2, KYN-54 (0.02%); group 3, MMTS (0.01%); group 4, CA (0.025%); and group 5, piroxicam (0.0125%). Group 1 (20 rats) was kept on the basal diet alone, and group 6 (12 rats) served as an untreated control. Rats in each group were killed at 6, 12, 18, or 24 weeks after the start of the experiment, and the yield of ACF in the colon of each group at 18 or 24 weeks was compared with that at 12 weeks. The number of ACF per rat colon of each group at 18 or 24 weeks was smaller than that at 12 weeks. The reduction rates at 18 weeks were 7% in group 1 (AOM alone), 11% in group 2 (AOM + KYN-54), 10% in group 3 (AOM + MMTS), 51% in group 4 (AOM + CA) (P < 0.01), and 33% in group 5 (AOM + piroxicam) (P < 0.02), while at 24 weeks they were 12%, 26%, 51% (P < 0.002), 43% (P < 0.05), and 70% (P < 0.001), respectively. These results indicate that chemopreventive agents for large bowel carcinogenesis, i.e., KYN-54, MMTS, CA, and piroxicam, are not only able to prevent the development of ACF, but also can regress ACF, which are regarded as precursor lesions of colorectal cancer. PMID- 9369930 TI - Isolation and characterization of invasive and noninvasive variants of a rat bladder tumor cell line. AB - We isolated, in vitro, spontaneous variants of the rat bladder tumor NBT-II cell line with a distinctive morphology. Of five sublines obtained, three (NBT-L1, L2a and L2b) exhibited an elongated shape and moderate to high invasive activity in vitro. The other two sublines (NBT-T1 and T2) formed tight colonies and exhibited very low or negligible invasive activity. The contents of mRNAs coding for E cadherin and cadherin-associated molecules (alpha-catenin and beta-catenin) were not correlated with the invasive activity of the cells. However, the expression level of the E-cadherin protein, but not those of catenins, was lower in invasive cells (NBT-L1, L2a and L2b) than in noninvasive cells (NBT-T1 and T2). Analysis of mRNAs coding for several growth factors and their receptors showed that the transforming growth factor alpha mRNA content in invasive cells was higher than that in noninvasive cells, and that the content of epidermal growth factor receptor mRNA was low in NBT-T2. Although NBT-II is known to acquire a fibroblastic appearance and cell motility in response to several growth factors, the conditioned media of the invasive sublines hardly affected the morphology or motility of noninvasive cells. These results indicate that the decreased E cadherin expression is closely associated with the transition from the noninvasive to the invasive phenotype of the bladder tumor cells, and that a post transcriptional process is important in the control of E-cadherin expression in the cells. These sublines may be useful as models for studies on the progression of bladder tumors. PMID- 9369931 TI - Coexpression of multiple Sertoli cell and Leydig cell marker genes in the spontaneous testicular tumor of F344 rat: evidence for phenotypical bifurcation of the interstitial cell tumor. AB - The development of testicular tumor has been frequently observed in some laboratory rat strains. In the present study, we have further characterized the testicular tumor that spontaneously develops in the F344 rat (F344/Jcl). Tumor cells first appeared in the interstitium and developed into multifocal nodular lesions. In the later stage, the whole testes were occupied by tumor cells that consisted of three different types of cells in morphological appearance: large clear type, small eosinophilic type and intermediate type. To determine the character of these cells, we examined the expression of marker genes for Sertoli cells (e.g., transferrin) and Leydig cells (e.g., 3 beta-hydroxysteroid dehydrogenase 1 (3 beta-HSD 1)). Transferrin and 3 beta-HSD 1 mRNAs were found in all 8 tumor samples analyzed by northern blotting. By in situ hybridization, we observed a substantial amount of 3 beta-HSD 1 mRNA and little or no transferrin mRNA in the large clear cells. In contrast, the small eosinophilic cells showed little or no 3 beta-HSD 1 mRNA and a large amount of transferrin mRNA, suggesting that the tumor was a mixture of at least two types of cells. Other Sertoli cell marker genes, such as cyclic protein 2 and sulfated glycoprotein 2, were expressed in all 8 tumors analyzed, and testin and steel factor (SLF), the c-kit receptor ligand, were also expressed in some of the tumors (testin, 75%; SLF, 25%), while other Leydig cell markers, LH receptor and c-kit, were expressed in 87% and 80% of the tumors, respectively. These results indicate that the spontaneous testicular tumor of F344 rat is of interstitium origin, showing phenotypical bifurcation possibly via transdifferentiation. PMID- 9369929 TI - Chemoprevention of azoxymethane-induced rat colon carcinogenesis by a xanthine oxidase inhibitor, 1'-acetoxychavicol acetate. AB - In our studies to find natural compounds with chemopreventive efficacy in foods, using azoxymethane (AOM)-induced colonic aberrant crypt foci and colonic mucosal cell proliferation as biomarkers, a xanthine oxidase inhibitor, 1' acetoxychavicol acetate (ACA), present in the edible plant Languas galanga from Thailand was found to be effective. This study was conducted to test the ability of ACA to inhibit AOM-induced colon tumorigenesis when it was fed to rats during the initiation or post-initiation phase. Male F344 rats were given three weekly s.c. injections of AOM (15 mg/kg body weight) to induce colonic neoplasms. They were fed diet containing 100 or 500 ppm ACA for 4 weeks, starting one week before the first dosing of AOM (the initiation feeding). The other groups were fed the ACA diet for 34 weeks, starting one week after the last AOM injection (the post initiation feeding). At the termination of the study (week 38), AOM had induced 71% incidence of colonic adenocarcinoma (12/17 rats). The initiation feeding with ACA caused significant reduction in the incidence of colon carcinoma (54% inhibition by 100 ppm ACA feeding and 77% inhibition by 500 ppm ACA feeding, P = 0.03 and P = 0.001, respectively). The post-initiation feeding with ACA also suppressed the incidence of colonic carcinoma (45% inhibition by 100 ppm ACA feeding and 93% inhibition by 500 ppm ACA feeding, P = 0.06 and P = 0.00003, respectively). Such inhibition was dose-dependent and was associated with suppression of proliferation biomarkers, such as ornithine decarboxylase activity in the colonic mucosa, and blood and colonic mucosal polyamine contents. ACA also elevated the activities of phase II enzymes, glutathione S-transferase (GST) and quinone reductase (QR), in the liver and colon. These results indicate that ACA could inhibit the development of AOM-induced colon tumorigenesis through its suppression of cell proliferation in the colonic mucosa and its induction of GST and QR. The results confirm our previous finding that ACA feeding effectively suppressed the development of colonic aberrant crypt foci. These findings suggest possible chemopreventive ability of ACA against colon tumorigenesis. PMID- 9369932 TI - Frequent somatic mutations of the APC and p53 genes in sporadic ampullary carcinomas. AB - Although a close relation of somatic mutations of the adenomatous polyposis coli gene with ampullary carcinomas in familial adenomatous polyposis patients has been reported, the possible association with sporadic ampullary neoplasms has not been fully examined. We have therefore investigated loss of heterozygosity at the adenomatous polyposis coli locus and the mutational status of a portion of the adenomatous polyposis coli gene, including the mutation cluster region, in 17 ampullary carcinomas of non-familial adenomatous polyposis patients. Alteration of the adenomatous polyposis coli gene was found in 8 of 17 (47.1%) cases, as missense or insertion mutations, with or without loss of heterozygosity. Additional investigation of p53 (exons 5-8) and K-ras (codons 12 and 13) gene mutations revealed a striking mutational pattern of the p53 gene. Nine of the 17 cases demonstrated a total of 12 mutations, 6 clustered at codon 189 and 3 at codon 166. Furthermore, 5 of the 12 mutations were nonsense mutations. Regarding the K-ras gene, 4 of the 17 (23.5%) cases had mutations in codon 12, 3 of the 4 cases being derived from the intraduodenal bile duct. The findings indicate that alterations of the adenomatous polyposis coli and the p53 genes are relatively frequent in sporadic ampullary carcinomas. In particular, the clustering at specific p53 codons might offer an etiological clue to clarify ampullary carcinogenesis. Mutations of the K-ras gene, on the other hand, might be characteristic of intraduodenal bile duct origin. PMID- 9369933 TI - Expressions of cell cycle regulators in human colorectal cancer cell lines. AB - To study the altered mechanisms of cell cycle regulation in colorectal cancer, the expressions of cyclins, cyclin-dependent kinases (CDKs), CDK inhibitors, p53 and retinoblastoma (Rb) protein were analyzed by western blotting in a series of human colorectal cancer cell lines. The colorectal cancer cell lines exhibited various expression patterns of cell cycle regulators, which may reflect differences in the biological characteristics of cancer cells and in the genetic backgrounds of carcinogenesis. A correlation was found between p53 gene alteration and p21 expression, suggesting that p53 gene mutation usually suppresses p21 expression, though p21 expression could be induced via both a p53 dependent and a p53-independent pathway in colorectal cancer. None of the cell lines studied expressed p16 protein, suggesting that inactivation of p16 may be a common alteration in colorectal cancer. Moreover, all the D-type cyclins, especially D2 and D3, were expressed at a high level in most of the cell lines. Loss of p16 expression and increased expression of D-type cyclins promote CDK mediated Rb phosphorylation. All of the colorectal cancer cell lines studied herein expressed Rb protein, but the growth-suppressive properties of Rb may be inactivated by the loss of p16 expression and increased expressions of D-type cyclins. In view of the pivotal role of Rb in cell cycle regulation, loss of p16 expression and overexpression of D-type cyclins may be critical alterations in colorectal cancer. PMID- 9369934 TI - NG-nitro-L-arginine methyl ester inhibits bone metastasis after modified intracardiac injection of human breast cancer cells in a nude mouse model. AB - We investigated the effects of NG-nitro-L-arginine-methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor, on bone metastasis of human breast cancer, MDA-231 cells. Tumor cells (2 x 10(5) cells in 0.2 ml of phosphate-buffered saline; PBS) were injected through the diaphragm into the left ventricle of the heart of laparotomized nude mice (male 5-week-old ICR-nu/nu). L-NAME (2 mg/mouse/injection in 0.1 ml of PBS) was given intraperitoneally to mice 6 h and 3 h before and immediately, 3 h, 6 h, 18 h and 21 h after the intracardiac injection of tumor cells. As a control, 0.1 ml of PBS was injected instead of L NAME. The effect of NG-nitro-D-arginine-methyl ester (D-NAME; 2 mg/mouse/injection), an inactive analogue of L-NAME, was also investigated to evaluate the specificity of L-NAME action. Radiographical examination 31 days after the tumor-cell injection showed that the incidence and number of osteolytic bone metastases and the number of bones with metastasis in L-NAME-treated mice were significantly reduced compared with those in PBS-treated mice (P < 0.05). The differences between PBS-treated and D-NAME-treated mice were not significant. Our findings suggest that specific and appropriate NOS inhibitors may represent a new pharmacological approach to therapy for cancer patients at risk of developing osteolytic bone metastases. PMID- 9369935 TI - Characterization of the extracellular domain in vascular endothelial growth factor receptor-1 (Flt-1 tyrosine kinase). AB - Flt-1 tyrosine kinase, vascular endothelial growth factor (VEGF) receptor-1, binds VEGF and a new VEGF-related ligand, placenta growth factor, but KDR/Flk-1 (VEGF receptor-2) binds only VEGF. To characterize the functional regions in the Flt-1 extracellular domain such as the ligand binding region and the dimer formation of the receptor, we constructed a series of mutants of the Flt-1 extracellular domain as soluble forms in a baculovirus system. We found that a region carrying the N-terminal 1st to 3rd immunoglobulin (Ig)-like domains of Flt 1 binds both ligands with high affinity. However, for dimer formation of soluble Flt-1, a region further downstream in the Flt-1 extracellular domain was required. Mutant Flt-1 receptors expressed in COS cells confirmed the requirement of the 4th to 7th Ig region for the activation of Flt-1 tyrosine kinase. Soluble Flt-1 carrying the N-terminal 1st to 3rd Ig region suppressed VEGF-dependent endothelial proliferation in vitro to the same level as the larger forms of soluble Flt-1, suggesting that the binding of one soluble Flt-1 molecule to one subunit of the VEGF homodimer may be sufficient to block the VEGF activity. PMID- 9369936 TI - Significance of basic fibroblast growth factor and fibroblast growth factor receptor protein expression in the formation of fibrotic focus in invasive ductal carcinoma of the breast. AB - A fibrotic focus (FF) is a scar-like area within invasive ductal carcinoma (IDC) of the breast, and has been shown to be a marker of high aggressiveness of IDC. In order to investigate the mechanism of FF formation in IDC, expression of basic fibroblast growth factor (bFGF) and fibroblast growth factor receptor (FGFR) was studied. One hundred and forty-nine IDCs were divided into solid tumors and scirrhous tumors. Immunohistochemistry was used to determine the expression of bFGF and FGFR proteins in both tumor cells and fibroblasts forming FF. Scirrhous tumors with FF showed a significantly higher frequency of bFGF protein expression than those without (P = 0.017), whereas, in solid tumors, the presence of FF was not significantly associated with the frequency of bFGF protein expression (P = 0.143). In addition, scirrhous tumors showed a significantly higher frequency of FGFR protein expression than solid tumors (P = 0.001). Among IDCs having FF and expressing bFGF protein, a significantly larger number of fibroblasts expressing FGFR protein within FF was observed in scirrhous tumors than in solid tumors (P = 0.016). The results of this study suggest that in scirrhous tumors the interaction between tumor cells and stromal fibroblasts plays an important role in the formation of FF, and that there is a paracrine mechanism between bFGF protein from tumor cells and FGFR protein in fibroblasts. PMID- 9369937 TI - Heterogeneity of DNA ploidy pattern in carcinoma of the gallbladder: primary and metastatic sites. AB - There are few detailed reports on the heterogeneity of the nuclear DNA ploidy pattern in carcinoma of the gallbladder. We studied twelve autopsied cases who died of extended gallbladder carcinoma. Multiple samples were taken from the primary site (Pri), from direct invasion of the liver (Hinf), from hematogenous metastasis to the liver (H), from lymphatic metastasis (LN) and from peritoneal dissemination (P). The DNA ploidy pattern was investigated by image cytometry. Heterogeneity of the DNA ploidy pattern in Pri, Hinf, H, LN and P was found in 7/11, 2/10, 5/10, 2/6 and 3/6 cases, respectively. Aneuploidy was more frequently found in Hinf than at the Pri. The DNA index of Hinf was significantly higher than that of Pri. Several stemlines, with different quantities of DNA, were found in Pri. Most of these stemlines were also observed in other sites. These facts may suggest that polyclonal cancer cells rather than one cancer cell or monoclonal cancer cells of a Pri metastasize or infiltrate, and that various polyclonal cancer cells proliferate to different degrees under different circumstances. PMID- 9369939 TI - Cytotoxicity of trimetrexate against antifolate-resistant human T-cell leukemia cell lines developed in oxidized or reduced folate. AB - Cytotoxicity of trimetrexate (TMQ), a lipophilic dihydrofolate reductase inhibitor, was examined in antifolate-resistant human T-cell leukemia cell lines developed in oxidized or reduced folate. An approximately 60-fold methotrexate (MTX)-resistant subline was developed in oxidized folate (pteroylglutamic acid: PGA) (CCRF-CEM/MTX60-PGA) from human T-cell leukemia cell line CCRF-CEM; this line exhibited impaired membrane transport of the drug. Further enhancement of MTX resistance resulted in selection of an approximately 5000-fold MTX-resistant subline (CCRF-CEM/ MTX5000-PGA), which showed increased dihydrofolate reductase activity due to gene amplification in addition to further impairment of MTX transport. An approximately 140-fold MTX-resistant subline, and then a 1500-fold MTX-resistant subline were developed in reduced folate (10 nM leucovorin) (CCRF CEM/MTX140-LV and CCRF-CEM/MTX1500-LV); they exhibited increased dihydrofolate reductase due to gene amplification accompanied by increased intracellular drug accumulation of MTX. While CCRF-CEM/MTX140-LV and CCRF-CEM/MTX1500-LV cells showed cross-resistance to TMQ, CCRF-CEM/MTX60-PGA and CCRF-CEM/MTX5000-PGA cells were at least as sensitive to TMQ as the parent cells. TMQ was more potent against approximately 200-fold N10-propargyl-5,8-dideazafolic-acid (CB3717) resistant human T-cell leukemia MOLT-3 sublines developed in PGA (MOLT 3/CB3717(200)-PGA) or leucovorin (MOLT-3/CB3717(200)-LV), as compared to the parent cells; MOLT-3/CB3717(200)-PGA and MOLT-3/CB3717(200)-LV cells were resistant to CB3717 by virtue of impaired transport, only the former possessing gene amplification of thymidylate synthase. The cytotoxicity of TMQ in both MOLT 3/CB3717(200)-PGA and MOLT-3/CB3717(200)-LV cells was reduced by addition of leucovorin in a dose-dependent manner, suggesting intracellular folate deficiency as a cause of TMQ sensitivity. These results demonstrate that TMQ overcomes transport-impaired antifolate resistance, irrespective of gene amplification of dihydrofolate reductase or thymidylate synthase. Types of folate used during the development of antifolate resistance seem to be important in relation to the mechanism of TMQ responsiveness as well as that of antifolate resistance. PMID- 9369938 TI - Anti-murine antibody response to mouse monoclonal antibodies in cancer patients. AB - Although development of human anti-murine immunoglobulin antibody (HAMA) is often seen in patients receiving murine antibodies, the variety of methods used for detecting HAMA makes it difficult to compare directly the HAMA responses measured by different assays. In the present study, several parameters of the HAMA response to two murine monoclonal antibodies were evaluated. The anti-sialosyl Tn antibody MLS102 and anti-CA125 antibody 145-9, which were labeled with 111In, were injected intravenously into 17 colorectal cancer patients and 11 ovarian cancer patients for immunoscintigraphy, respectively. HAMA was measured by enzyme linked immunosorbent assay. There was no difference in baseline HAMA levels before antibody injection between the two groups. HAMA developed more frequently in ovarian cancer patients receiving the 145-9 antibody than in colorectal cancer patients receiving the MLS102 antibody (9/11 vs. 6/17, P < 0.05). No significant difference was observed in maximal HAMA levels between the two groups of patients. However, time to reach the maximal levels was delayed and the duration of the response seemed longer in ovarian cancer patients. Among 11 patients receiving the 145-9 antibody three patients became positive for HAMA more than 2 months after antibody injection and the other two had HAMA activity in their sera for more than 17 months. HAMA response was different between the two antibodies, and late onset or long duration of HAMA response against the 145-9 antibody suggests the importance of HAMA measurement in patients who receive a second injection of murine antibodies even after a long interval. PMID- 9369940 TI - Effects of bioreductive agents, tirapazamine and mitomycin C, on quiescent cell populations in solid tumors, evaluated by micronucleus assay. AB - Mice bearing transplantable solid tumors received 10 intraperitoneal administrations of 5-bromo-2'-deoxyuridine (BrdU) to label the proliferating (P) tumor cells, and were then irradiated with 60Co gamma-rays or injected with cis diamminedichloroplatinum (II) (cisplatin). The tumor cells were isolated and incubated with cytochalasin-B (a cytokinesis blocker). The micronucleus (MN) frequency in the cells without BrdU labeling, which were regarded as quiescent (Q) cells in the tumor, was determined using immunofluorescence staining for BrdU. The MN frequency in the total (P + Q) tumor cell population was determined from tumors that were not pretreated with BrdU. Pretreatment with tirapazamine, a bioreductive agent, could enhance the sensitivity of tumor cells, including Q cells, to radiation more markedly than mitomycin C pretreatment as judged from an in vivo assay immediately after irradiation. Post-irradiation administration of tirapazamine produced a large post-irradiation radiosensitizing effect on both the total and Q tumor cell populations in vivo. Cisplatin treatment combined with tirapazamine demonstrated that tirapazamine also has a chemosensitizing potential for both the total and Q tumor cell populations. We confirmed that the sensitivity of Q cell populations to radiation and chemotherapy using cisplatin can be enhanced by combined treatment with tirapazamine. PMID- 9369941 TI - Detection of MAGE-4 protein in the sera of patients with hepatitis-C virus associated hepatocellular carcinoma and liver cirrhosis. AB - The aim of this study was to determine whether MAGE-4 protein is detectable in sera of patients with hepatocellular carcinoma and other liver diseases. An enzyme-linked immunosorbent assay was employed for detection of MAGE-4 protein in sera of liver disease patients, healthy men and women (control I) and those undergoing prostatic cancer screening (control II). MAGE-4 protein levels in sera of patients with hepatitis C virus-associated HCC (HCC-C) (n = 45, mean = 2.160 ng/ml) and HCV-associated cirrhosis (LC-C) (n = 55, 1.072 ng/ml) were significantly higher (P < 0.0001) than those of control I (0.327 ng/ml) or control II (0.394 ng/ml). MAGE-4 protein was positive in 21/45 (46.7%) HCC-C patients and 18/55 (32.7%) LC-C patients (cut-off, mean plus 2 SD in healthy controls) but in 0/12 (0%) hepatitis B virus-associated HCC (HCC-B) patients, 3/49 (6.1%) hepatitis B virus-associated LC (LC-B) patients, 4/47 (8.5%) alcoholic liver disease patients, and 1/49 (2.0%) controls. Serum MAGE-4 protein level may be useful as a marker for identification of LC-C patients suffering from HCC that is undetectable by presently available methods. PMID- 9369942 TI - Functional role of endogenous CD14 in lipopolysaccharide-stimulated bone resorption. AB - Lipopolysaccharide (LPS) is a bacterial cell component that plays multifunctional roles in inflammatory reactions, and one of these roles is that of a powerful stimulator of bone resorption. However, the mechanism by which LPS stimulates bone resorption is not yet understood. In the present study, we show, by using mouse embryonic calvarial cells, that endogenous CD14 and interleukin-1 beta (IL 1 beta) play an important role in the LPS-mediated bone resorption and that interferon-gamma (IFN-gamma) functions as a strong inhibitor of this resorption by suppressing LPS-stimulated expression of CD14 and IL-1 beta genes in the calvarial cells. We observed that LPS-stimulated differentiation of osteoclastic cells and bone resorption were markedly neutralized by anti-mouse CD14 antibody and were clearly inhibited by anti-sense CD14 oligonucleotide treatment. In addition, because LPS stimulated CD14 gene expression in the calvarial cells, these observations demonstrate the precise role of endogenous CD14 in LPS stimulated differentiation of osteoclastic cells and bone resorption. However, the stimulation of the differentiation of osteoclastic cells and bone resorption was also inhibited by anti-mouse IL-1 beta antibody. Interestingly, anti-sense CD14 oligonucleotide inhibited LPS-stimulated expression of the IL-1 beta gene in the calvarial cells. These observations suggest a functional role of endogenous CD14 in LPS-stimulated expression of the IL-1 beta gene in the cells. Because IFN gamma is a potent inhibitor of bone resorption stimulated by IL-1, in additional experiments, we examined whether IFN-gamma is able to inhibit LPS-stimulated differentiation of osteoclastic cells and bone resorption. We found that IFN gamma inhibited these stimulations by suppressing CD14 and IL-1 beta genes in the calvarial cells. The present study thus clearly demonstrates a functional role of endogenous CD14 in LPS-stimulated bone resorption. PMID- 9369943 TI - PMA-induced activation of the p42/44ERK- and p38RK-MAP kinase cascades in HL-60 cells is PKC dependent but not essential for differentiation to the macrophage like phenotype. AB - The signaling mechanisms leading to phorbol ester myristate (PMA)-induced differentiation of HL-60 cells to the macrophagelike phenotype were investigated by using different protein kinase inhibitors. The protein kinase C inhibitor Ro 31-8220 specifically blocks PMA-induced differentiation, activation of the p42/44ERK- and p38RK-MAP kinase cascades and Hsp27-phosphorylation in HL-60 cells. Because Ro 31-8220 does not inhibit activation of the MAP kinase cascades by protein kinase C (PKC)-independent signals such as epidermal growth factor (EGF), heat shock, or anisomycin in these cells, only PMA-induced activation of the MAP kinases can be downstream of PKC. The MEK1 inhibitor PD 098059 and the p38RK inhibitor SB 203580 also were used to analyze whether the PMA-induced PKC dependent activation of MAP kinases is involved in the differentiation process. Under certain conditions, PD 098059 can completely block the PMA-induced activation of the p42ERK as monitored by immunoprecipitation kinase assay by using the substrate myelin basic protein. SB 203580 specifically inhibits activation of p38RK as judged by MAPKAP kinase 2 activity against the substrate Hsp27 and also blocks Hsp27 phosphorylation in the cells. In contrast, neither PD 098059 nor SB 203580 nor both inhibitors together prevent PMA-induced differentiation of the HL-60 cells to the macrophagelike phenotype. The results suggest the existence of a diversification of PMA-induced signaling in HL-60 cells downstream of PKC, leading to activation of MAP kinases that are not essential for differentiation and to phosphorylation of other, so far unidentified, targets responsible for differentiation. PMID- 9369944 TI - c-Myb function in fibroblasts. AB - The protooncogene c-myb is a nuclear transcription factor that shares significant sequence homology with two other myb family members, A-myb and B-myb. Recent studies have suggested that c-myb is involved in regulation of the cell cycle via control of intracellular calcium [Ca2+]i concentration. Given the limited cell type expression of the c-myb gene, we set out to investigate whether myb dependent cell cycle regulation occurs in cells not known to express the c-myb protein. NIH 3T3 fibroblasts were stably transfected with an inducible c-myb dominant negative construct composed of a myb DNA binding domain linked to the Drosophila engrailed transcription suppresser (pGREMEn) and a full-length murine c-myb cDNA sequence. Induced expression of the dominant negative construct was associated with a G1 cell cycle arrest and a failure to increase late G1 intracellular calcium levels. Similar expression studies in mouse embryonic fibroblasts derived from the c-myb knockout mouse have demonstrated lower baseline [Ca2+]i levels than in normal mice fibroblasts that were not further lowered by MEn expression. We conclude that regulation of calcium homeostasis and cell cycle progression via myb-dependent transcription may play an important role in cells not possessing detectable levels of c-myb protein. PMID- 9369945 TI - Regulation of human monocyte matrix metalloproteinases by SPARC. AB - SPARC (secreted protein, acidic and rich in cysteine), also called osteonectin or BM-40, is a collagen-binding glycoprotein secreted by a variety of cells and is associated with functional responses involving tissue remodeling, cell movement and proliferation. Because SPARC and monocytes/macrophages are prevalent at sites of inflammation and remodeling in which there is connective tissue turnover, we examined the effect of SPARC on monocyte matrix metalloproteinase (MMP) production. Treatment of human peripheral blood monocytes with SPARC stimulated the production of gelatinase B (MMP-9) and interstitial collagenase (MMP-1). Experiments with synthetic peptides indicated that peptide 3.2, belonging to the alpha helical domain III of SPARC, is the major peptide mediating the MMP production by monocytes. SPARC and peptide 3.2 were also shown to induce prostaglandin synthase (PGHS)-2 as determined by Western and Northern blot analyses. The increase in PGHS-2 stimulated by SPARC or peptide 3.2 correlated with substantially elevated levels of prostaglandin E2 (PGE2) and other arachidonic acid metabolites as measured by radioimmunoassay and high performance liquid chromatography (HPLC), respectively. Moreover, the synthesis of MMP was dependent on the generation of PGE2 by PGHS-2, since indomethacin inhibited the production of these enzymes and their synthesis was restored by addition of exogenous PGE2 or dibutyryl cAMP (Bt2cAMP). These results demonstrate that SPARC might play a significant role in the modulation of connective tissue turnover due to its stimulation of PGHS-2 and the subsequent release of PGE2, a pathway that leads to the production of MMP by monocytes. PMID- 9369946 TI - Hypoxia affects cytokine production and proliferative responses by human peripheral mononuclear cells. AB - We have shown that hypoxia (2% O2 approximately pO2 14 mmHg) as opposed to O2 atmospheric pressure (20.9% O2 approximately pO2 140 mmHg) can deeply affect the production of cytokines in human peripheral mononuclear cells (PBMC) in the presence or absence of a specific T-cell activator such as phytohemagglutinin (PHA). In hypoxia, interleukin (IL)-2, IL-4, and interferon (IFN)-gamma production increased by 110, 70, and 50% over that of controls, respectively, in PHA-stimulated PBMC (P < 0.05). Moreover, in hypoxia, IL-6 production was significantly enhanced in both resting and PHA-stimulated PBMC by 36 and 37%, respectively (P < 0.05). However, in hypoxia, IL-10 production decreased in both resting and stimulated PBMC, being 80 and 67% of controls, respectively (P < 0.05). PBMC proliferation was not significantly affected by hypoxia, although PBMC susceptibility to PHA was about 80% of that of the control (P < 0.05) after 40 hr of treatment, whereas the cycle progression of hypoxic PBMC was delayed. From an evaluation of these results, hypoxia apparently modifies the production of cytokines by PBMC. These results have both theoretical and practical interest because local hypoxia is very common in several conditions, such as inflammation and local ischemia, and is a host-nonspecific defense against infection. Furthermore, these results suggest a differential pattern of cytokine production in vivo in hypoxic tissues. PMID- 9369947 TI - Cytoskeletal-dependent activation of system A for neutral amino acid transport in osmotically stressed mammalian cells: a role for system A in the intracellular accumulation of osmolytes. AB - System A activity for neutral amino acid transport is increased after hypertonic shock in NBL-1 (an epithelial cell line) and CHO-K1 cells (a nonepithelial cell line) by a mechanism which is consistent with the synthesis of a regulatory protein that activates preexisting system A carrier proteins (Ruiz-Montasell et al., 1994, Proc. Natl. Acad. Sci. USA, 91,9569-9573). In this study, we have further investigated this biological response by determining the role of cytoskeletal structures in system A regulation by hypertonic stress. Using inhibitors of the microfilament and microtubule networks, we show that the increase in system A activity after hypertonic treatment requires the integrity of both cytoskeletal structures in NBL-1 cells, although the increase in system A activity triggered by amino acid starvation is completely insensitive to any of these drugs. In contrast, the enhancement of system A activity in osmotically stressed CHO-K1 cells is not sensitive to inhibitors of the microtubule network. In both cell types, the results suggest that the inhibitors block the increase of system A activity. System A transport decreases when CHO-K1 cells return to isotonic conditions by a mechanism that is insensitive to inhibitors of protein and mRNA synthesis. The increase in system A transport activity is also followed by the accumulation of neutral amino acids (fourfold for alanine), which is totally blocked by the same agents (cycloheximide and actinomycin D) that prevent the increase in system A activity after hypertonic treatment, thus indicating that system A is crucial for maintaining a high concentration of organic osmolytes inside the cell. PMID- 9369948 TI - Expression cloning of a mammalian amino acid transporter or modifier by complementation of a yeast transport mutant. AB - A cDNA clone named L21 was isolated from L6 rat muscle cells by complementation of a yeast proline transport mutant. L21 cDNA has 2,268 bp and codes for a peptide of 228 amino acids with four potential transmembrane domains. The amino acid sequence of L21 shows no homology to any known proteins. Expression of L21 cDNA enables the mutant yeast to grow in proline as the sole nitrogen source and to transport proline, alpha-aminoisobutyric acid (AIB) and leucine. The Km for proline is about 1.0 mM. The substrate specificity of L21 expressed in yeast shows no striking similarity to known mammalian amino acid transporters. PMID- 9369949 TI - Arachidonate initiated protein kinase C activation regulates HeLa cell spreading on a gelatin substrate by inducing F-actin formation and exocytotic upregulation of beta 1 integrin. AB - HeLa cell spreading on a gelatin substrate requires the activation of protein kinase C (PKC), which occurs as a result of cell-attachment-induced activation of phospholipase A2 (PLA2) to produce arachidonic acid (AA) and metabolism of AA by lipoxyginase (LOX). The present study examines how PKC activation affects the actin- and microtubule-based cytoskeletal machinery to facilitate HeLa cell spreading on gelatin. Cell spreading on gelatin is contingent on PKC induction of both actin polymerization and microtubule-facilitated exocytosis, which is based on the following observations. There is an increase in the relative content of filamentous (F)-actin during HeLa cell spreading, and treating HeLa cells with PKC-activating phorbol esters such as 12-O-tetradecanoyl phorbol 13-acetate (TPA) further increases the relative content of F-actin and the rate and extent to which the cells spread. Conversely, inhibition of PKC by calphostin C blocked both cell spreading and the increase of F-actin content. The increased F-actin content induced by PKC activators also was observed in suspension cells treated with TPA, and the kinetics of F-actin were similar to that for PKC activation. In addition, PKC epsilon, which is the PKC isoform most involved in regulating HeLa cell spreading in response to AA production, is more rapidly translocated to the membrane in response to TPA treatment than is the increase in F-actin. Blocking the activities of either PLA2 or LOX inhibited F-actin formation and cell spreading, both of which were reversed by TPA treatment. This result is consistent with AA and a LOX metabolite of AA as being upstream second messengers of activation of PKC and its regulation of F-actin formation and cell spreading. PKC appears to activate actin polymerization in the entire body of the cell and not just in the region of cell-substrate adhesion because activated PKC was associated not only with the basolateral plasma membrane domain contacting the culture dish but also with the apical plasma membrane domain exposed to the culture medium and with an intracellular membrane fraction. In addition to the facilitation of F-actin formation, activation of PKC induces the exocytotic upregulation of beta 1 integrins from an intracellular domain to the cell surface, possibly in a microtubule-dependent manner because the upregulation is inhibited by Nocodazole. The results support the concept that cell-attachment induced AA production and its metabolism by LOX results in the activation of PKC, which has a dual role in regulating the cytoskeletal machinery during HeLa cell spreading. One is through the formation of F-actin that induces the structural reorganization of the cells from round to spread, and the other is the exocytotic upregulation of collagen receptors to the cell surface to enhance cell spreading. PMID- 9369950 TI - Heparin suppresses sgk, an early response gene in proliferating vascular smooth muscle cells. AB - Vascular smooth muscle cell (VSMC) hyperplasia plays a central role in chronic and acute vascular pathology including arteriosclerosis and restenosis following vascular surgery. The glycosaminoglycans of the heparan sulfate class, including heparin, inhibit VSMC proliferation in animals and in culture. Heparin binds to high affinity sites on the cell surface, selectively modulates mitogenic signal transduction pathway(s), and rapidly alters transcription of several genes. To further explore the molecular mechanisms responsible for this growth inhibition, we have employed the differential display technique to identify heparin-regulated genes. Here we demonstrate that heparin inhibits the expression of the early response gene sgk (serum and glucocorticoid-regulated kinase). The expression of sgk is not inhibited by chondroitin sulfate, a nonantiproliferative glycosaminoglycan, suggesting that sgk suppression may play a functional role in the antiproliferative effect of heparin. This idea is strengthened by the finding that heparin does not inhibit sgk expression in VSMCs resistant to the antiproliferative effect of heparin or in vascular endothelial cells which are unresponsive to heparin. Expression of sgk mRNA diminishes with increasing concentrations of heparin. Finally, sgk expression is not suppressed by other growth inhibitors such as transforming growth factor-beta 1 (TGF-beta 1) and interferon-beta (IFN-beta), suggesting separate and distinct effects of these growth inhibitors on the mitogenic pathway. PMID- 9369951 TI - Differential expression of the keratinocyte growth factor (KGF) and KGF receptor genes in human vascular smooth muscle cells and arteries. AB - Keratinocyte growth factor (KGF) is a secreted member of the fibroblast growth factor (FGF) family of heparin-binding proteins. Studies reported to date indicate that it functions primarily as an important paracrine mediator of epithelial cell growth and differentiation. KGF appears to act via binding to a specific FGF receptor-2 isoform generated by an alternative splicing mechanism. To determine whether KGF may play a role in vascular smooth muscle cell (SMC) biology, we investigated KGF and KGF receptor gene expression in human SMC cultured in vitro as well as in several human nonatherosclerotic artery and atheroma specimens. KGF mRNA but not KGF receptor mRNA was expressed by SMCs, as determined by Northern blot hybridization analysis or reverse transcription polymerase chain reaction assays, respectively. Additional experiments demonstrated that 1) human SMCs produce and secrete mitogenically active KGF and that 2) the cytokine interleukin-1 increases KGF mRNA and protein levels in human SMCs. We also found that KGF transcripts but not KGF receptor transcripts were expressed in control and atherosclerotic human arteries. Taken together, these results indicate that KGF is unlikely to be involved in SMC growth regulation unless it can function intracellularly or interact with a presently unidentified KGF receptor. PMID- 9369952 TI - Bradykinin- and thrombin-induced increases in endothelial permeability occur independently of phospholipase C but require protein kinase C activation. AB - We determined whether activation of phosphatidylinositol-specific phospholipase C (PI-PLC) and a subsequent increase in cytosolic calcium concentration ([Ca2+]i) was an obligatory signaling event mediating the increase in transendothelial permeability induced by bradykinin (BK) and alpha-thrombin (alpha-T). Both BK and alpha-T (each at a concentration range of 0.01-1 microM) caused dose-dependent increases in transendothelial 125I-albumin permeability in cultured bovine pulmonary artery endothelial cell monolayers. Both agonists also produced a rise in inositol (1,4,5)-trisphosphate [Ins(1,4,5)P3] by 10 sec that was followed by a prolonged increase in [Ca2+]i. Pretreatment of endothelial cells with the PLC inhibitor, 1-(6-((17 beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1 H pyrrole-2,5-dion [(U73122) at 10 microM for 15 min], prevented the increases in Ins(1,4,5)P3 and [Ca2+]i induced by both BK and alpha-T. However, inhibition of PLC with U73122 or another PLC inhibitor, neomycin, did not prevent the increase in endothelial permeability induced by either agonist. In contrast, depletion of cellular protein kinase C (PKC) with phorbol-12-myristate 13-acetate (0.01 microM for 20 hr) increased both BK- and alpha-T-induced phosphoinositide turnover but inhibited the agonist-induced increase in permeability. A PKC inhibitor, staurosporine (5 microM) likewise inhibited the BK-induced increase in endothelial cell permeability to albumin. We conclude that increases in endothelial permeability induced by the inflammatory mediators, BK and thrombin, can occur independently of PLC activation and increased [Ca2+]i but that a PKC dependent pathway is required for the permeability response. PMID- 9369954 TI - Factor X-dependent, thrombin-generating activities on a neuroblastoma cell and their disappearance upon differentiation. AB - Some tumor cells induce platelet aggregation in the bloodstream, which has been implicated in tumor metastasis. In this study, we investigated the mechanism of platelet aggregation induced by a human neuroblastoma cell line, GOTO. It was revealed that GOTO cells had tissue factor on their surface and converted factor X (FX) to FXa with the aid of factor VIIa. The produced FXa formed prothrombinase complex on the cells and activated prothrombin. From experiments on activity inhibition by specific monoclonal as well as polyclonal antibodies, it was concluded that factor V did not constitute this prothrombinase complex. Another cofactor known to constitute prothrombinase complex on some cells, effector cell protease receptor-1 (EPR-1), was not expressed on GOTO cells, suggesting that the cofactor composing FXa-dependent prothrombinase activity on GOTO cells is not factor V or EPR-1 but, rather, is an unknown molecule. Upon the culturing in the presence of 5-bromo-2'-deoxyuridine for 4 days, GOTO cells differentiated into Schwann-like cells, and both FXase and prothrombinase activities were greatly diminished. Flow cytometric analyses revealed that the decrease of FXase activity should be attributed to the decrease of tissue factor expression on GOTO cells. Because these activities greatly diminished upon cellular differentiation, the expression of both cofactor molecules may be related to the malignant and metastatic nature of the tumor cells. PMID- 9369953 TI - Altered proton extrusion in cells adapted to growth at low extracellular pH. AB - Intracellular pH (pHi) homeostasis is crucial to cell survival. Cells that are chronically exposed to a low pH environment must adapt their hydrogen ion extrusion mechanisms to maintain their pHi in the physiologic range. An important component of the adaptation to growth at low pH is the upregulation of pHi relative to the extracellular pH (pHe). To test the ability of low pHe adapted cells to respond to a pHi lowering challenge, a fluorescence assay was used that directly monitors proton removal as the rate of change of pHi during recovery from cytosolic acidification. Two cell lines of Chinese hamster origin (ovarian carcinoma and ovary fibroblastoid cells) were compared, both of which showed altered proton extrusion after adaptation to growth at low pHe = 6.70. In the ovarian carcinoma (OvCa) cell line, the pattern was consistent with an upregulation by means of an increase in the number of functional proton transporters in the plasma membrane. In the ovary fibroblastoid (CHO-10B) cell line, pHi was consistently elevated in adapted cells as compared with cells grown at normal pHe = 7.30 without an increase in maximum extrusion rate. This upregulation was consistent with a shift in the activating pHi of proton transporters without an increase in the number of transporters, i.e., a change in substrate affinity of the transporter. In OvCa cells, recovery from acidification could be blocked by amiloride, an inhibitor of Na+/ H+ exchange. In contrast, a more modest effect of amiloride on CHO cells was observed but a complete inhibition was seen with the Cl-/HCO(-3)exchange inhibitor 4,4' diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS). These data indicate that the two cell lines rely to different degrees on the two major pathways for pH regulation during recovery from cytosolic acidification. PMID- 9369955 TI - Cell behavior and cell-matrix interactions of human palmar aponeurotic cells in vitro. AB - The present investigation has been performed to better characterize, in vitro, normal aponeurotic cells in comparison with dermal fibroblasts and with cells derived from Dupuytren's affected aponeuroses. Cells were cultured in monolayer and/or into three-dimensional collagen gels. Cell structure, adhesion, and spreading capability on different substrates, as well as integrin expression were investigated by light and electron microscopy and by flow cytometry. Cell-matrix interactions were also analyzed by gel retraction experiments in the presence, or absence, of RGD peptides and anti-integrin antibodies. Normal aponeurotic cells, compared with dermal fibroblasts, exhibited in vitro peculiar structural features, which were substantially maintained in Dupuytren's aponeurotic cells, irrespective of the substrate they were grown on. By contrast, the aponeurotic cell behavior was different in normal and diseased cells, these latter approaching that of dermal fibroblasts. Normal aponeurotic cells, in fact, were characterized by low efficiency in retracting the collagen gel, low alpha 2, alpha 1, and alpha 5 integrin subunit expression and low adhesion properties onto collagen and fibronectin, whereas cells isolated from the aponeuroses of Dupuytren's patients exhibited higher capability of retracting the collagen gel, increased adhesion properties toward collagen and fibronectin, and higher levels of integrin expression. No differences were observed between dermal fibroblasts from Dupuytren's patients or from normal subjects. These in vitro results are consistent with those previously obtained in situ, suggesting that palmar aponeurotic cells have a peculiar phenotype and that changes in cell-matrix interactions occur in Dupuytren's contracture. Moreover, by comparing data obtained from the retracted fibrotic cords and the still clinically unaffected aponeuroses of the same patients, it may be noted that Dupuytren's disease is not only confined to the clinically involved branches, but includes the whole aponeurosis of the affected hand. PMID- 9369956 TI - Human cystatin C forms an inactive dimer during intracellular trafficking in transfected CHO cells. AB - To define the cellular processing of human cystatin C as well as to lay the groundwork for investigating its contribution to lcelandic Hereditary Cerebral Hemorrhage with Amyloidosis (HCHWA-I), we have characterized the trafficking, secretion, and extracellular fate of human cystatin C in transfected Chinese hamster ovary (CHO) cells. It is constitutively secreted with an intracellular half-life of 72 min. Gel filtration of cell lysates revealed the presence of three cystatin C immunoreactive species; an 11 kDa species corresponding to monomeric cystatin C, a 33 kDa complex that is most likely dimeric cystatin C and immunoreactive material, > or = 70 kDa, whose composition is unknown. Intracellular monomeric cystatin C is functionally active as a cysteine protease inhibitor, while the dimer is not. Medium from the transfected CHO cells contained only active monomeric cystatin C indicating that the cystatin C dimer, formed during intracellular trafficking, is converted to monomer at or before secretion. Cells in which exit from the endoplasmic reticulum (ER) was blocked with brefeldin A contained the 33 kDa species, indicating that cystatin C dimerization occurs in the ER. After removal of brefeldin A, there was a large increase in intracellular monomer suggesting that dimer dissociation occurs later in the secretion pathway, after exiting the ER but prior to release from the cell. Extracellular monomeric cystatin C was found to be internalized into lysosomes where it again dimerized, presumably as a consequence of the low pH of late endosome/lysosomes. As a dimer, cystatin C would be prevented from inhibiting the lysosomal cysteine proteases. These results reveal a novel mechanism, transient dimerization, by which cystatin C is inactivated during the early part of its trafficking through the secretory pathway and then reactivated prior to secretion. Similarly, its uptake by the cell also leads to its redimerization in the lysosomal pathway. PMID- 9369957 TI - PTHrP and cell division: expression and localization of PTHrP in a keratinocyte cell line (HaCaT) during the cell cycle. AB - Parathyroid hormone-related protein (PTHrP) is highly expressed in normal skin keratinocytes, and its involvement in growth and differentiation processes in these cells has been implicated by several lines of evidence which include the use of antisense PTHrP (Kaiser et al., 1994, Mol. Endocrinol., 8:139-147). In this study, we have investigated whether PTHrP expression and its subcellular localization is linked to cell cycle progression in a human keratinocyte cell line (HaCat), which constitutively expresses and secretes PTHrP. PTHrP mRNA and immunoreactive PTHrP were assessed in asynchronous dividing cells and in cells blocked at G1 or G2 + M phases of the cell cycle using several different protocols. The response of PTHrP mRNA expression was examined following readdition of serum in the continued presence of cycle blockers, and after release from cell cycle block, or from cell synchronization by serum deprivation. PTHrP expression was greatest in actively dividing cells when cells were in S and G2 + M phases of the cell cycle and were lowest in quiescent G1 cells. Most notable were the high levels of PTHrP mRNA and protein in cells at G2 + M phase of the cell cycle at division. Furthermore, PTHrP was localized to the nucleolus in quiescent cells, but redistributed to the cytoplasm when cells were actively dividing. Taken together, these results support a role for PTHrP in cell division in keratinocytes. In asynchronously growing cells, PTHrP expression fell as cells became confluent at a time when cell growth is inhibited and cells begin to differentiate. Mitogen stimulation of HaCaT cells resulted in a rapid increase in PTHrP mRNA expression, but was dependent upon cells being in the G1 phase of the cell cycle. Cells blocked in G1 responded to mitogen both in the continued presence of aphidicolin or when released from block. Cells blocked at G2 + M with colcemid expressed high levels of PTHrP mRNA and protein, and PTHrP mRNA did not respond further to mitogen in the continued presence of blocker. However, in cells released from block at G2 + M by addition of serum, an increase in PTHrP expression was seen coincident with the progression of cells into G1. In contrast, in a squamous cancer cell line (COLO16), basal PTHrP expression was high and was not altered during the cell cycle or by cell cycle block, consistent with association of its dysregulated expression in malignant cells. The results of this study suggest that PTHrP may have two roles in the cell cycle; one in G1 in response to mitogen, and a second at cell division when its expression is high and it is relocated from the nucleolus to the cytoplasm. PMID- 9369958 TI - Characterization of a 60-kDa cell surface-associated transforming growth factor beta binding protein that can interfere with transforming growth factor-beta receptor binding. AB - We have characterized a 60-kDa transforming growth factor-beta (TGF-beta) binding protein that was originally identified on LNCaP adenocarcinoma prostate cells by affinity cross-linking of cell surface proteins by using 125I-TGF-beta 1. Binding of 125I-TGF-beta 1 to the 60-kDa protein was competed by an excess of unlabeled TGF-beta 1 but not by TGF-beta 2, TGF-beta 3, activin, or osteogenic protein-1 (OP-1), also termed bone morphogenetic protein-7 (BMP-7). In addition, no binding of 125I-TGF-beta 2 and 125I-TGF-beta 3 to the 60-kDa binding protein on LNCaP cells could be demonstrated by using affinity labeling techniques. The 60-kDa TGF beta binding protein showed no immunoreactivity with antibodies against the known type I and type II receptors for members of the TGF-beta superfamily. Treatment of LNCaP cells with 0.25 M NaCl, 1 microgram/ml heparin, or 10% glycerol caused a release of the 60-kDa protein from the cell surface. In addition, we found that the previously described TGF-beta type IV receptor on GH3 cells, which does not form a heterometric complex with TGF-beta receptors, could be released from the cell surface by these same treatments. This suggests that the 60-kDa protein and the similarly sized TGF-beta type IV receptor are related proteins. The eluted 60 kDa LNCaP protein was shown to interfere with the binding of TGF-beta to the TGF beta receptors. Thus, the cell surface-associated 60-kDa TGF-beta binding protein may play a role in regulating TGF-beta binding to TGF-beta receptors. PMID- 9369959 TI - Surveillance after potentially curative cancer treatment. PMID- 9369960 TI - Expression of retinoid-responsive genes occurs in colorectal carcinoma-derived cells irrespective of the presence of resistance to all-trans retinoic acid. AB - BACKGROUND AND OBJECTIVES: Retinoids are metabolized in human intestinal epithelial cells to all-trans retinoic acid; however, it is unknown whether these cells express retinoid receptors, and whether sensitivity or resistance to the hormone is associated with a particular pattern of expression of retinoid responsive genes. METHODS: Northern blot analysis and reverse transcriptase polymerase chain reaction (RT-PCR) were used to identify mRNAs for retinoid receptors. Both Relative RT-PCR and transfection of retinoid-inducible plasmid were applied to test functionality of the pathway in a model system for colorectal carcinoma progression (primary SW480, all-trans retinoic acid sensitive cells vs. metastatic SW620, -insensitive cells). RESULTS: Three colorectal carcinoma-derived cell lines were inhibited by the hormone. Retinoic acid receptor type alpha (hRAR alpha) and retinoid X receptor type alpha (hRXR alpha) mRNAs were detected in normal enterocytes, colonocytes, and in all colorectal carcinoma-derived cells studied. Primary carcinomas and metastatic lesions expressed high amounts of hRAR alpha receptor protein, showing no simple correlation between the amounts of mRNA and receptor protein. No pattern of expression of the retinoid-responsive genes was associated with sensitivity or resistance to the retinoid. Expression of the genes occurred irrespective of resistance to the hormone or inactivity of the pathway. CONCLUSIONS: Colonocytes possess a molecular system for transduction of the retinoid signal. All-trans retinoic acid modifies gene expression and inhibits proliferation of these cells. Therefore, retinoids are likely to be effective in chemoprevention of colorectal carcinoma. PMID- 9369961 TI - The role of stromal cells in the expression of interstitial collagenase (matrix metalloproteinase-1) in the invasion of gastric cancer. AB - BACKGROUND AND OBJECTIVES: In one of the steps of tumor invasion and metastasis, tumor cells must invade surrounding tissues and degrade the components of the basement membranes. Interstitial collagenase (matrix metalloproteinase-1: MMP-1) has been also investigated in relation to cancer invasion and metastasis. METHODS: We investigated the formation and mechanism of MMP-1 expression using gastric cancer cell lines and gastric fibroblasts derived from normal gastric mucosa by ELISA and immunohistochemistry. RESULTS: Production of MMP-1 protein in gastric fibroblasts was stimulated significantly by adding the conditioned medium of MKN-74. Localization of MMP-1 protein in the xenografted gastric cancer cell lines was heterogeneous according to different cell lines. CONCLUSIONS: These results suggested that the production of MMP-1 protein in tumor invasion was regulated by interaction between stromal cells, particularly fibroblasts, and tumor cells. PMID- 9369962 TI - Low level c-myc gene amplification in gastric cancer detected by dual color fluorescence in situ hybridization analysis. AB - BACKGROUND AND OBJECTIVES: By using the dual color fluorescence in situ hybridization analysis, the amplification of c-myc gene can be detected in the tumor tissue samples obtained from patients with gastric cancer, and the relationship between the molecular cytogenetic change and the clinical stage or histological type may be clarified. METHOD: The tumor tissue samples were obtained from 21 patients with gastric cancer. Simultaneous detection of signals from the chromosome 8 centromere and c-myc gene in each cell after hybridization with appropriate probes was carried out on 50-200 tumor cells in each case. RESULTS: Chromosome 8 polysomy was found in 10 patients. The average centromere 8 copy number was significantly higher in differentiated (2.7) than in undifferentiated (2.3) types of gastric cancer. However, there was no significant difference in occurrence of polysomy 8 between early and advanced cancer. The relative gain (1.1-1.9) of c-myc copy number was found in all 21 cases. There was no significant difference in the fraction of cells with c-myc gene amplification between early (pT1) and advanced (pT2-4) carcinomas. CONCLUSION: We conclude that the present dual color fluorescence in situ hybridization of gastric cancer may be useful in the evaluation of low level c-myc gene amplification, which is difficult to detect by Southern blotting, and may be applicable to the diagnosis of early gastric cancer. PMID- 9369963 TI - Multimodality treatment of noninflammatory stage IIIb breast cancer. AB - BACKGROUND AND OBJECTIVES: The 1990s have established the contribution of multimodality therapy in the management of IIIb noninflammatory breast cancer (IIIb NIBC), by reducing the odds of recurrence and death. METHODS: A total of 300 women with IIIb NIBC received a multimodality therapy. The treatment consisted of neoadjuvant chemotherapy [FAC (5-fluorouracil, Adriamycin, cyclophosphamide) regimen], radical (Halsted) mastectomy or modified (Patey mastectomy), postoperative radiotherapy, and adjuvant chemohormone therapy [FAC regimen + cyclophosphamide, 5-fluorouracil and methotrexate (CMF) regimen or Tamoxifen]. RESULTS: Complete or partial clinical response (CR or PR) after neoadjuvant chemotherapy was obtained in 83% patients. Ninety-nine patients (33%) survived 5 years without evidence of disease (NED). The uni- and multivariate analyses factors that had significant influence on the treatment results were: clinical response to neoadjuvant chemotherapy, pathological tumor size, and microscopical status of the axillary lymph nodes. CONCLUSIONS: We conclude that neoadjuvant FAC regimen chemotherapy is very effective in producing objective tumor regression and offers the benefit of radical mastectomy to patients with previously unresectable IIIb NIBC. PMID- 9369964 TI - Chemotherapy is a safe and effective initial therapy for infected malignant breast and chest wall ulcers. AB - BACKGROUND AND OBJECTIVES: Locally advanced breast cancers may form large, infected skin ulcers, which were traditionally treated with radiation therapy. Neoadjuvant chemotherapy is now standard treatment for locally advanced breast cancer. METHODS: The response of 33 patients with ulcerated breast cancer to primary chemotherapy was retrospectively analyzed. Antibiotics were not used in primary treatment. Tumor and ulcer responses were evaluated independently. RESULTS: Chemotherapy alone healed 18 of these ulcers. Neither responding nor refractory patients developed sepsis during this treatment. CONCLUSIONS: Chemotherapy is safe and effective treatment for patients with infected malignant breast ulcers and does not cause systemic sepsis. PMID- 9369965 TI - Endometrial carcinoma in the south of Israel: study of 231 cases. AB - BACKGROUND AND OBJECTIVES: Endometrial carcinoma is the commonest female genital tract malignancy in the south of Israel. The purpose of this study was to investigate the clinical and histologic findings, treatment and outcome of patients with endometrial carcinoma in the south of Israel. METHODS: Data from the files of 231 patients with endometrial carcinoma who were managed at the Soroka Medical Center between January 1961 and December 1994 were evaluated. RESULTS: Endometrial carcinoma was more prevalent among Jewish as compared to Arab-Beduin women, and among Ashkenazi as compared to Sephardic Jewish women. The prevailing presenting symptom was postmenopausal bleeding and most patients (68.8%) had Stage I disease. Most patients (209/225, 92.9%) underwent surgery, 131/222 (59%) had radiotherapy and 15/214 (7%) received chemotherapy. The 5-year survival rate was 79.1% overall; 89% for Stage I, 71.7% for Stage II, 21.6% for Stage III and 0% for Stage IV; 89.8% for Grade 1, 70% for Grade 2 and 60.9% for Grade 3; 100% for adenoacanthoma, 82% for endometrioid carcinoma, 65.8% for adenosquamous carcinoma and 51.6% for papillary serous carcinoma. CONCLUSIONS: Endometrial carcinomas are characterized by a relatively favorable prognosis with a 5-year survival of about 80%. Surgical stage, histologic differentiation and histologic subtype are sensitive predictors of survival. The mainstay of treatment is surgery with adjuvant pelvic radiotherapy when necessary. PMID- 9369966 TI - Intraoperative intrapleural hypotonic cisplatin treatment for carcinomatous pleuritis. AB - BACKGROUND AND OBJECTIVES: We recently developed a new intraoperative intrapleural hypotonic cisplatin treatment for carcinomatous pleuritis found at thoracotomy in non-small cell lung cancer patients. In the present study, the efficacy and adverse events of this treatment as well as the pharmacokinetics of cisplatin in the blood after the treatment were evaluated. PATIENTS AND METHODS: Twenty-one patients received the treatment for 15 minutes after completing the intrathoracic surgical procedures. The total and free platinum levels in the blood of five patients were then measured. As a control, 29 patients without such treatment were reviewed retrospectively. RESULTS: The survival rates in the treatment and non-treatment groups were similar. The pleural disease free survival of the treated patients was, however, significantly higher than that of the non-treated patients. Such pleural disease as effusion and the growth of the pleural disseminated tumors only appeared in three of the 21 (14%) treated patients while 26 of 29 (90%) non-treated patients had clinically detected pleural disease. The blood platinum levels after the treatment were extremely low and such low levels probably induced no systemic adverse events after the treatment. The only adverse event of this treatment was an increase in the postoperative drainage volume. CONCLUSIONS: These observations seem to suggest that intraoperative intrapleural hypotonic cisplatin treatment for carcinomatous pleuritis found at thoracotomy can, at least, delay the appearance of the pleural disease without any adverse events. PMID- 9369968 TI - Colon polyps. AB - Colon polyps may be single or multiple, noninherited or inherited, histologically may vary from inflammatory, hamartomatous, neurogenic, or adenomatous, and may be benign or malignant. The various recognized syndromes are discussed including their clinical presentation, malignant potential, and associated tumors. Recognition of these clinical syndromes will allow the clinician to categorize the patient and the relative risk. The discussion goes into the genetic studies identifying the adenomatous polyposis coli gene on chromosome 5 q21 and the identification of mutations arising in the DNA repair genes (MSA2, MLH1, PMSI, and M52) in the HNPCC syndrome. This identified two divergent pathologies, both involving "multiple hits" with mucosal cells going from normal to adenoma dysplasia-carcinoma. The understanding of the multiple hit concept with the adenoma-dysplasia-carcinoma progression will aid in the further understanding of the broad neoplastic process. PMID- 9369967 TI - Primary malignant melanoma of the esophagus. AB - A 48-year-old woman presented with a 6-month history of dysphagia, often associated with retrosternal chest pain. Upper endoscopy revealed an unusual pigmented lesion within the middle portion of the esophagus, and multiple biopsies were obtained. The histopathology and immunohistochemical profile of the tissue specimens were diagnostic of malignant melanoma. A thorough clinical and radiographic evaluation was performed, providing no additional findings or alternative primary source. Of approximately 11,500 melanoma patients entered in the Duke University melanoma database since 1970, this represents the only case of primary esophageal melanoma. The case is described and a review of the literature is presented. PMID- 9369969 TI - Use of aromatase inhibitors in postmenopausal women with advanced breast cancer. AB - Surgeons have been involved in the management of metastatic breast cancer since the technique of ovarian ablation was introduced in 1896. However, as newer hormonal and chemotherapeutic regimens were developed, drug therapy gradually replaced surgery as the preferred treatment for metastatic breast cancer. Thus, management of metastatic breast cancer has largely shifted from surgeons to medical oncologists. Advances in hormonal pharmacology have placed hormonal therapy alongside surgery and radiation therapy as a standard treatment option for women with advanced breast cancer. The purpose of this article is to update surgeons on the current use of hormonal agents for treatment of advanced breast cancer in postmenopausal women, and to review the aromatase inhibitors, a new line of hormonal agents for the treatment of advanced breast cancer. PMID- 9369970 TI - Protective mechanisms of adenosine in neurons and glial cells. AB - As illustrated in Figure 1, a disturbance of the intracellular Ca2+ homeostasis is thought to be a common pathogenic factor for the generation of secondary nerve cell damage that develops after brain trauma or stroke or during the course of neurodegenerative diseases. A neuronal Ca2+ overload which may result from an excessive glutamate-evoked membrane depolarization and consecutive Ca2+ influx as well as from an activation of metabotropic receptors and consecutive intracellular Ca2+ mobilization is known to have direct toxic effects on the cytoskeleton and the cell metabolism of neurons. In addition, a Ca(2+)-dependent activation of glial cells along with the loss of physiologically required mature astrocyte functions and with the acquisition of potentially neurotoxic microglial properties, has more recently been recognized as an additive pathogenic factor. This may provide an effective target for pharmacological interference. Specifically, the reinforcement of an endogenous homeostatic regulator, which obtained its sophisticated know-how during evolution, may provide a neuroprotective therapy which can handle the complexity of the pathological process with a minor risk of pharmacological side effects. Adenosine is such an ancient molecular signal that acts on both neurons and glial cells. In neurons, adenosine activates K+ and Cl- conductances, which limits synaptically evoked depolarization, thus counteracting the Ca2+ influx through voltage-dependent and NMDA receptor-operated ion channels. This A1 receptor-mediated effect seems to be the major action by which adenosine adds directly to the protection of neurons against Ca(2+)-dependent damage. In glial cells, the prevalent effect of adenosine is its regulatory influence on the Ca2+ and cAMP-dependent molecular signaling that determines the cellular proliferation rate, the differentiation state and related functions. When mimicking the activation of metabotropic glutamate receptors in cultures of immature rat astrocytes, which largely resemble pathologically activated astrocytes, a transient Ca2+ mobilization was initiated by adenosine. This A1 receptor-mediated Ca2+ signal caused a prolonged potentiation of the A2 receptor-mediated intracellular cAMP rise. An experimentally sustained enhancement of the cAMP signaling initiated the differentiation of cultured astrocytes and the new expression of K+ and Cl- channels which are required for the physiological astrocyte function to maintain the extracellular ion homeostasis. Evidence is accumulating that a strengthening of the cAMP signaling, which can be achieved by adenosine agonists and also by the pharmacon propentofylline (an adenosine uptake blocker and phosphodiesterase inhibitor), stimulates the mRNA production of neurotrophic factors in astrocytes. In cultured microglial cells, several days' treatment with adenosine agonists or propentofylline markedly inhibited their proliferation rate, the in vitro spontaneously occurring transformation into macrophages and their particularly high formation of free oxygen radicals. Adenosine agonists also depressed the release of the potentially toxic cytokine TNF alpha and induced programmed cell death in immunologically activated microglial cells. We conclude that a pharmacological reinforcement of the endogenous cell modulator adenosine may provide neuroprotection by counteracting neuronal Ca2+ overload, by depressing potentially neurotoxic microglial functions and by regaining physiologically required properties of differentiated astrocytes. Further information about the influence of adenosine on the molecular signaling and on ischemic brain damage is given in Refs. 37 and 38, and about the implicated possible relevance for the treatment of stroke in Ref. 39. PMID- 9369972 TI - Adenosine A1 receptor agonists as clinically viable agents for treatment of ischemic brain disorders. PMID- 9369971 TI - Modulation of apoptosis by adenosine in the central nervous system: a possible role for the A3 receptor. Pathophysiological significance and therapeutic implications for neurodegenerative disorders. PMID- 9369973 TI - Adenosine A2A receptors and neuroprotection. AB - The adenosine A2A receptor subtype is one of the four adenosine receptors that have been identified in the mammalian organism. In addition to being found in blood vessels, platelets and polymorphonuclear leukocytes, the A2A receptors are abundant in the central nervous system, especially in the striatum. The recent development of selective A2A receptor ligands, in particular of receptor antagonists, makes it possible to elucidate the function of A2A receptors in normal and altered conditions. Pharmacological studies have shown that A2A receptor antagonists are potentially effective for treatment of neurodegenerative processes such as Parkinson's disease. Their activity is attributed to the close anatomical and functional links between A2A receptors and dopaminergic pathways in the basal ganglia. More recently, A2A receptor antagonists have proved to be active in models of cerebral ischemia. While the mechanisms underlying the role of A2A receptors in the hypoxia/ ischemia processes remains to be clarified, it is recognized that A2A receptor antagonists counteract the effects of excitatory aminoacids, which are massively released after cerebral ischemia. Another function of A2A receptors is related to protection from seizures, but further studies are needed to elucidate their specific interaction, if any, with neuronal excitability. Altogether, the great advance recently made with the discovery of selective A2A receptor ligands provides increasing information on the function of A2A receptors and opens new perspectives for treatment of neurological disorders. PMID- 9369974 TI - Adenosine A3 receptor and brain. A culprit, a hero, or merely yet another receptor? PMID- 9369975 TI - Prophylactic actions of melatonin in oxidative neurotoxicity. PMID- 9369976 TI - In vitro and in vivo protective effects of melatonin against glutamate oxidative stress and neurotoxicity. PMID- 9369977 TI - Neuroprotective action of the pineal hormone melatonin against excitotoxicity. Receptor abuse-dependent antagonism (RADA). PMID- 9369978 TI - Calcium-activated proteolysis as a therapeutic target in cerebrovascular disease. PMID- 9369979 TI - The calpain proteolytic system in neonatal hypoxic-ischemia. AB - Neonatal rats were subjected to transient cerebral hypoxic-ischemia (HI, unilateral occlusion of the common carotid artery +7.70% O2 for 100 min) and allowed to recover for up to 14 days. Calpain caseinolytic activity was found to increase in both hemispheres for at least 20 hr. Hypoxic exposure per se increased the activity of calpains, more pronounced in a membrane-associated fraction, probably through interaction with cellular components, whereas HI introduced a loss of activity, most likely through consumption and loss of proteases. Consecutive tissue sections were stained with antibodies against calpastatin, alpha-fodrin, the 150-kDa breakdown product of alpha-fodrin (FBDP, marker of calpain proteolysis) or microtubule-associated protein 2 (MAP-2, marker of dendrosomatic neuronal injury). Areas with brain injury displayed a distinct loss of MAP-2, which clearly delineated the infarct. FBDP accumulated in injured and borderline regions ipsilaterally, and a less conspicuous, transient increase in FBDP also occurred in the contralateral hemisphere, especially in the white matter. The cytosolic fraction (CF) and the membrane and microsomal fraction (MMF) of cortical tissue were subjected to Western blotting and stained with antibodies against calpain, calpastatin and the 150-kDa breakdown product of alpha-fodrin (FBDP). Calpain immunoreactivity decreased bilaterally in the CF during the insult (62-68% of controls) and remained significantly lower during early recovery, whereas the MMF showed no significant changes. This translocation of calpains coincided with the appearance of FBDP in the ipsilateral, HI hemisphere, displaying a significantly higher level of FBDP from immediately after the insult until at least 1 day of recovery (204-292% of controls). No significant changes in FBDP were found in the contralateral, undamaged hemisphere, despite translocation of calpains in both hemispheres, a prerequisite for calpain activation. This discrepancy may be related to changes in the endogenous inhibitor, calpastatin. Calpastatin protein was found to decrease during and shortly after HI in the ipsilateral, but not the contralateral, hemisphere. The inhibitory activity of calpastatin also tended to decrease after HI, indicating that a reduction of calpastatin may be necessary for extensive calpain activation to occur. The mRNA of m-calpain increased in the HI hemisphere 48 hr after the insult (167%, p < 0.001), a time point when the protein was also increased. In summary, our findings indicate that calpains are activated during HI and in the early phase of reperfusion after HI, preceding neuronal death. PMID- 9369981 TI - Calpain, a mediator of myelin breakdown in demyelinating diseases. PMID- 9369980 TI - Role of calpain and its inhibitors in tissue degeneration and neuroprotection in spinal cord injury. PMID- 9369982 TI - The role of dendritic dysfunction in neurodegeneration. PMID- 9369983 TI - Compensatory long-term effect of perinatal hypoxia-ischemia. A possible mechanism for neuroprotection? PMID- 9369984 TI - Toxin-induced blood vessel inclusions caused by the chronic administration of aluminum and sodium fluoride and their implications for dementia. PMID- 9369985 TI - Role of heat shock proteins in MPTP-induced neurotoxicity. AB - 1. MPTP and its major metabolite MPP+ have significant effects on body temperature regulation in mice, which are both age and strain dependent. 2. These effects were produced by intraperitoneal injection of either MPTP or MPP+ suggesting that the predominant site of action lies outside the blood-brain barrier. 3. The initial hyperthermia induced in CD-1 mice, which was sufficient to lead to the induction of HSP 72, appears to have a protective effect with regard to striatal dopamine depletion. 4. Cultured CHO cells are sensitive to MPP+ cytotoxicity at high concentrations. This toxicity can be reduced by heat shocking the cells prior to the addition of MPP(+)-containing media. 5. In summary, these in vivo and in vitro data strongly suggest that heat shock proteins (HSP 72) play a neuroprotective role in MPTP-induced neurotoxicity. PMID- 9369986 TI - Inflammatory gene expression in cerebral ischemia and trauma. Potential new therapeutic targets. AB - This review summarized evidence in support for the case that ischemia elicits an inflammatory condition in the injured brain. The inflammatory condition consists of cells (neutrophils at the onset and later monocytes) and mediators (cytokines, chemokines, others). It is clear that de novo upregulation of proinflammatory cytokines, chemokines and endothelial-leukocyte adhesion molecules in the brain follow soon after the ischemic insult and at a time when the cellular component is evolving. The significance of the inflammatory response to brain ischemia is not fully understood. Evidence is emerging in support of the possibility that the acute inflammatory reaction to brain ischemia may be causally related to brain damage. This evidence includes: 1) the capacity of cytokines to exacerbate brain damage; 2) the capacity of specific cytokine antagonists such as IL-1ra to reduce ischemic brain damage; 3) that depletion of circulating neutrophils reduces ischemic brain injury; 4) and that antagonists of the endothelial-leukocyte adhesion interactions (e.g., anti-ICAM-1) reduce ischemic brain injury. However, it should be kept in mind that cytokines were also argued to provide beneficial effects in brain injury as inferred from studies with TNF-receptor knock-out mice (p55 and p75 knock-out), which display increased sensitivity to brain ischemia, and the capacity of IL-1 to elicit the state of ischemic tolerance upon repeated administration. Nevertheless, the recent revelation on the capacity of ischemia to induce acute inflammation in the brain provides a new and fertile ground for new explorations for novel therapeutic agents that could confine the neuronal damage that follows ischemia. Furthermore, many of the genes that are upregulated by ischemia have growth-promotion capacity and therefore raise the possibility that such gene products may be useful in counteracting brain damage by enhancing repair and establishing compensatory mechanisms that enhance histological and functional recovery. PMID- 9369987 TI - Excitotoxic mechanisms of neurodegeneration in transmissible spongiform encephalopathies. AB - Endogenous excitatory amino acids (EAAs) such as glutamic or aspartic acids have been proposed to mediate the brain damage to EAA receptor-rich brain sites that is caused by a variety of external toxic agents (glutamic acid, domoic acid, kainic acid, ibogaine, trimethyltin (TMT), 3-nitropropionic acid (3-NPA)), as well as from such naturally-occurring age-related neurodegenerative diseases as Alzheimer's disease, Huntington's chorea, and Parkinson's disease. Sites often damaged include the hypothalamus (glutamate), the hippocampal and neocortical pyramidal neurons (domoic acid), the cerebellar Purkinje neurons (ibogaine) and the corpus striatum (3-NPA, amphetamine). The excitotoxic damage occurs to neuronal cell bodies and their dendrites, resulting in a characteristics appearance of pyknotic neurons surrounded by their vacuolated, swollen dendrites. Axons passing through the region that lack EAA receptors are completely spared. However, astrocytes with swollen perikarya and nuclei (Alzheimer's type II "reactive" astrocytes) are often observed in the vicinity of the lesions. Animal and human "Prion Diseases" or "Transmissible Spongiform Encephalopathies" (TSEs) result (after a period of months to years) in a neurodegenerative picture characterized by pyknotic neurons surrounded by vacuoles with numerous reactive astrocytes in the vicinity of the damage. In addition, amyloid deposits composed of a protease-resistant protein (PrPSc) characteristic of the particular host species with the disease are found near the degenerating neurons. By using different strains of the scrapies TSE agent to inoculate hamsters and mice, reproducible models of hypothalamic, hippocampal, or cerebellar damage resulting in the appropriate functional deficits may be obtained. Because of the close similarity in the appearance, localization, and functional consequences from TSE neuropathology compared to some of the well-known EAA syndromes, we propose that excitotoxic mechanisms may play a role in the pathogenesis of TSE neurodegenerative diseases. The similarity in pathogenesis of the neurodegenerative processes in excitotoxicity compared to TSE diseases also implies that neuroprotective strategies against excitotoxicity may also be effective against TSEs. PMID- 9369988 TI - Toward the development of strategies to prevent ischemic neuronal injury. In vitro studies. AB - Cerebellar granule cells in culture, which are extremely vulnerable to excitotoxin glutamate or N-methyl-D-aspartate (NMDA), were used to study mechanisms of neuronal cell death and protection. Paradoxically, pretreatment of these cells with subtoxic concentrations of NMDA markedly blocked the neurotoxicity resulting from subsequent exposure to glutamate or NMDA. The NMDA mediated neuroprotection can be antagonized by pretreatment of these cells with protein synthesis inhibitors, suggesting an involvement of protein(s) with neuroprotectant properties, most likely neurotrophic factors. Because basic fibroblast growth factor (BFGF) is well known to prevent neuronal cell death following mechanical or chemical injury, we have tested whether NMDA increases the synthesis of bFGF in cerebellar granule cells. NMDA elicited a rapid and time dependent increase in bFGF mRNA, suggesting that availability of this trophic factor may play a role in the NMDA-mediated neuroprotection. PMID- 9369989 TI - Low-affinity NMDA receptor antagonists. The neuroprotective potential of ARL 15896AR. PMID- 9369990 TI - Neuroprotective effects of eliprodil in a rat hippocampal slice hypoxia model. PMID- 9369992 TI - Effect of selective brain cooling during cerebral ischemia on postischemic brain water content in rabbit. PMID- 9369991 TI - The rationale for, and effects of oxygen delivery enhancement to ischemic brain in a feline model of human stroke. AB - Reduced brain tissue oxygenation is frequently seen in severe head injury and after subarachnoid hemorrhage, and this is considered a major cause of secondary ischemic brain injury. In fact, in a previous study, we found a tight correlation between low brain tissue oxygen tension and poor outcome. Therefore, we tested the hypothesis that an allosteric modifier of hemoglobin, which improves oxygen transport to tissue, could reduce the size of an acute infarct in a feline model of human stroke. This compound produces a shift in the hemoglobin dissociation curve to the right and therefore facilitates the unloading of oxygen during low oxygen tension. Seventeen adult cats were studied. Ischemic stroke was induced through a transorbital, permanent, middle cerebral artery occlusion. Seven animals received saline, and 10 received the allosteric Hb modifier RSR-13. Three different endpoints were used to determine the effect of the allosteric modifier. Delta p50 values were measured in the arterial blood; the intra-infarct oxygen tension was measured, and finally, the volume of the infarct was assessed using TTC staining. Mean delta p50 changes varied from 10.4 +/- 9.2 mmHg up to 15.0 +/- 6.8 mmHg. Mean intra-infarct oxygen tension was 27 +/- 6 mmHg for the control group and 33 +/- 7 mmHg for the drug-treated animals. The mean infarct size (measured as percentage of hemisphere volume) in the control group was 32 +/- 9% and for the RSR-13 animals 22 +/- 10% (p < 0.05). A definitive trend towards improvement in brain oxygen tension was seen, such that animals pretreated with RSR-13 showed a higher infarct oxygen tension. Infarct size was significantly reduced in the drug group. Therefore, RSR-13 is potentially beneficial in the treatment of brain ischemia. Since human studies with this compound are already completed, and other compounds which increase oxygen delivery, such as perfluorocarbons, are already being evaluated, it is likely that oxygen delivery enhancement will rapidly become the first 'neuroprotective' modality, employed in patients with severe brain injury, stroke and subarachnoid hemorrhage. PMID- 9369993 TI - An advanced in vitro model to study hypoxia/low glucose-induced neuronal cell damage and death. PMID- 9369994 TI - Does effect of a neuroprotective agent on volume of experimental animal cerebral infarct predict effect of the agent on clinical outcome in human stroke? PMID- 9369995 TI - Neuroprotection in surgery. Development of a pharmacologic cocktail for intraoperative use. PMID- 9369996 TI - Clinical trials in traumatic brain injury. What can we learn from previous studies? AB - Many compounds have now been tested that were expected to ameliorate the secondary ischemic brain damage after severe head injury. Thus far, none of these have been clearly successful. This review is an attempt to identify factors that could be responsible for some of these failures. Recommendations are made that could help to avoid these pitfalls in the future. The usefulness and criteria for use of animal models for traumatic brain injury to depict human head injury are discussed. Clearly, it has now become widely accepted that mechanism-driven trials, in which individual pathophysiological mechanisms are targeted, are preferable in this heterogeneous patient population. Other factors, such as the effect of brain penetration, safety and tolerability of the compound, and the interface between the pharmaceutical industry and academics are a major influence in the success of these trials. Furthermore, different ways of analyzing trials such as sequential analysis and newer, alternative end points should be considered. Pharmacological agents will never be the "magic bullet" for a process as heterogenous in pathophysiological mechanisms as traumatic brain injury. This does not imply that the role of neuroprotective compounds will not be important in the future. New approaches in developing, conducting and analyzing these expensive clinical trials must be devised in the future. PMID- 9369997 TI - Cocaine dependence. A clinical syndrome requiring neuroprotection. AB - Cocaine use has increased the frequency of medical complications among younger individuals. Neurological and neurovascular complications include strokes, seizures, transient ischemic attacks, and headaches. Subclinical deficits in cerebral perfusion and EEG have been noted in this population. Although these subclinical deficits may be an indication of increased risk of medical complications, the prophalactic treatment of cocaine abusers with neuroprotective agents has not yet been advocated. Blood flow of the anterior and medial cerebral arteries was measured by transcranial Doppler sonography in cocaine abusers (n = 70) and control subjects (n = 20) to determine whether cocaine abusers might have reduced cerebral blood flow in large cerebral arteries. Blood flow was measured within three days of and again about 28 days after admission of subjects to an inpatient research ward to determine whether blood flow improved with monitored abstinence. The mean, systolic, and diastolic velocities as well as the Pulsatility Index (PI) in both arteries differed between the control and cocaine abusers (p < 0.05). After about a month of abstinence, blood flow for the cocaine dependent subjects increased. These preliminary findings suggest that blood flow is reduced in cocaine abusers and that there is a slight improvement with abstinence. Further research is needed to determine whether blood flow in abstinent cocaine abusers can be increased by pharmacological manipulations. PMID- 9369998 TI - Subclinical neurological and neurovascular deficits in cocaine dependence. Gender and psychosocial considerations. AB - Neurological and neurovascular deficits were reported in cocaine abusers. In order to examine the contribution of cocaine use severity as well as other psychosocial factors to these deficits, we examined the following measures in a sample of cocaine abusers (n = 70): blood flow (transcranial Doppler sonography), and psychosocial measures (the Norbeck Social Support Questionnaire, the Symptom Check List 90R, the Beck Hopelessness Scale, and the Ellison Wellness Scale). Blood flow in the anterior and medial cerebral arteries was lower in the cocaine abusers than in the control subjects. Both cocaine use and psychosocial measures significantly predicted decreases in blood flow. PMID- 9369999 TI - Astrocyte metallothioneins (MTs) and their neuroprotective role. AB - I have briefly detailed in this review the role of astrocytes in MeHg neurotoxicity, emphasizing the mechanisms and significance of astrocytic swelling in neuropathological conditions. I have also described the functions of brain MTs and have reported recent observations on their propensity to attenuate cytotoxicity. While it is unclear why three different MT genes are expressed in the brain, this redundancy should allow for greater accumulation of MTs under stressful conditions compared to its accumulation if only a single gene was present. Another explanation may be that genes encoding functionally identical MTs might be regulated independently, thus permitting cell-specific MT expression. Finally, each of the three MT isoforms may have distinct functions. As discussed herein, astrocytic MTs afford protection from the acute cytotoxic effects of MeHg, reversing the effect of this organometal on RVD and inhibition of taurine release. Whether other vital cellular functions are protected by MTs will have to await future studies, as will the mechanisms associated with MT induced cellular protection. That the resistance to heavy metal toxicity is closely related to the cellular ability to synthesize MTs, raises interesting questions regarding the potential involvement of heavy metals in neurodegenerating (amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease) under conditions of compromised MT synthesis. Future studies on the expression and regulation of MT genes are likely to culminate in novel strategies for manipulating intracellular MT levels, providing insight to their role in both health and disease. PMID- 9370000 TI - Neuregulins as potential neuroprotective agents. PMID- 9370002 TI - Ion channels as targets for neuroprotective agents. PMID- 9370001 TI - Poly(ADP-ribose) polymerase (PARP) revisited. A new role for an old enzyme: PARP involvement in neurodegeneration and PARP inhibitors as possible neuroprotective agents. PMID- 9370003 TI - Is low molecular weight heparin a neuroprotectant? AB - This communication reports the results of investigations on the effect of low molecular weight heparin (LMWH) on intraneuronal calcium release, and considers its possible relevance to the treatment of ischemic stroke. It previously was shown that intraneuronal injection of conventional heparin (MW 12,000) in vitro prevents glutamate-induced calcium release from intracellular stores through its blocking action on IP3 (inositol-1,4,5-triphosphate) receptors, and thus interferes with events occurring in the ischemic cascade. In the experiments reported herein, a LMWH of MW 4500 was shown to have these same effects when injected into a Purkinje cell in an in vitro cerebellar slice preparation, and also when administered externally (bath application). By contrast, conventional heparin works only when injected into the cell; bath application has no effect. The results are interpreted to mean that the larger conventional heparin molecule cannot pass through the cell membrane, while the smaller LMWH molecule does indeed enter the cell. In a clinical trial, LMWH begun within 48 hours of ischemic stroke onset in humans improved outcome at 6 months; conventional heparin given in a similar trial was without benefit. That one anticoagulant was beneficial while another failed suggests the possibility that the difference was independent of effect on the clotting system. The experimental data herein reported support the view that LMWH may benefit stroke victims by an action directly cytoprotective against the consequences of neuronal ischemia. PMID- 9370004 TI - Pharmacology of the AMPA antagonist 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo-(F) quinoxaline. PMID- 9370005 TI - Current and future approaches to neurotoxicity risk assessment. PMID- 9370006 TI - Young male drinkers and impaired driving intervention: results of a U.S. telephone survey. AB - The present study examines the role of interveners in the driving behavior of a group of drivers at higher risk for involvement in a fatal, alcohol-related motor vehicle accident than the general population, based on their demographic characteristics. The sample consisted of men, aged 21-34 years, living in areas where alcohol-involved motor vehicle fatalities most commonly occur. More than one-half (55%) of these men reported having been the target of an intervention to prevent them from drinking and driving. The variables most strongly associated with having been the target of an intervention were: involvement in an accident after drinking; frequency of driving after drinking too much to drive safely; binge drinking; reporting that it takes ten or more drinks to feel drunk. Age, total alcohol consumption and the relationship between the target and the intervener predicted intervention success. Persons who have close relationships with drinking drivers, particularly wives/girlfriends, are most likely to be successful in preventing these men from drinking and driving. To the extent they can be encouraged to safely intervene, wives/girlfriends and close friends may be potential targets for messages promoting informal social control of drinking and driving. PMID- 9370007 TI - Alcoholism at the time of injury among trauma center patients: vehicular crash victims compared with other patients. AB - A structured in-depth interview employing standardized criteria was used to determine the prevalence of lifetime and current alcohol dependence (alcoholism) in unselected consecutive patients admitted to a regional Level I trauma center. Of 629 patients, 157 (25.0%) were current alcoholics at the time of injury. An additional 87 (13.8%) were diagnosed as lifetime non-current alcoholics. There was no significant difference in the rates of current alcohol dependence among patients injured in vehicular crashes (23.5%), other unintentional trauma victims (29.3%), and those injured as a result of violence (24.6%). Of BAC+ (blood alcohol concentration positive) patients, 54.5% were current alcoholics. However, 14.4% of alcohol-negative patients were also diagnosed as alcohol dependent. PMID- 9370008 TI - Close-following drivers on two-lane highways. AB - This study was intended first to replicate, on two-lane highways, of the Evans and Wasielewski (Accident Analysis & Prevention 14, 57-64, 1982; 15, 121-136, 1983) results on the connection between close-following driving and traffic offenses and, second, to reveal reasons for close-following. A sample of close following drivers (N = 157) and control drivers (N = 178) was picked from the flow on two-lane main highways. The driver records of the past 3 years showed retrospectively that the close-followers had accumulated 2.3 times more traffic offenses than had the control drivers and 2.0 times more when mileage was taken into account. The result is in agreement with the Evans and Wasielewski results for multi-lane highways, with the additional check for mileage in these data. However, the effect only occurred in males and was more marked in young males. Close-following females even indicated a tendency of having fewer offenses than their controls when their higher mileage was taken into account. Another sample of close-followers interviewed on the road revealed that hurry or desire to overtake the car ahead was the justification for the close-following in the majority of cases. It was suggested that on two-lane highways close-following substantially stems from overtaking needs and maneuvering connected to higher target speeds. This study partly confirms the connection between close-following and an increased number of offenses in comparisons between drivers. However, the suggested connection between close-following and accident involvement, as based on interindividual comparisons, still remains somewhat open. PMID- 9370009 TI - Paediatric slow-speed non-traffic fatalities: Victoria, Australia, 1985-1995. AB - An important group of fatal incidents are slow-speed pedestrian non-traffic incidents to children, which account for 14% of accidental deaths from all causes in Victorian children under 5 years of age between 1985 and 1995, and 12% of pedestrian deaths of all ages. In Victoria, Australia, the database of the state Consultative Council on Obstetric and Paediatric Morbidity and Mortality was utilised to identify paediatric slow-speed pedestrian non-traffic-accident deaths in the local population. Additional data relating to the car and its driver, the child, and the circumstances of the incident were abstracted from records kept by the State Coroner and the Victorian compulsory third party traffic injury insurance organisation. Twenty eight Victorian children were identified who had died in one of three types of incident (driverless cars, child interacting with the vehicle and driver, and drivers who were unaware of the child's proximity). These incidents were more common in rural areas compared with urban, usually occurring at the child's home. The child was with or near an adult on all occasions. The vehicle was usually being driven by a relative, and was reversing in a higher proportion of 'unaware' incidents compared with the 'interactive' type. The association of 'off-road' family vehicles and trucks with these incidents appears to be increasing, especially in recent years. These findings suggest some countermeasures, including the separation of vehicle driveways from children's play areas, and object vicinity ultrasonic warning devices for vehicles. PMID- 9370010 TI - Safety knowledge of users and non-users of the lap belt on two-point motorized belt systems. AB - A field study of 1146 drivers and passengers of vehicles equipped with motorized passive belts was conducted in shopping malls and other locations in the states of Arizona and Indiana. The Indiana data was collected the summer of 1994 and the Arizona data the summer of 1995. Shoulder belt use by drivers and passengers was 93.4% in Indiana and 87.8% in Arizona. Lap belt use was 65% in Indiana and 69.9% in Arizona. Over 99% of drivers in both states knew that a manually fastened lap belt was provided along with the motorized shoulder belt. Most drivers agreed that they are supposed to wear the lap belt (96.3% in Indiana and 94.3% in Arizona) and said that the vehicle they were driving provided a warning signal when the lap belt was not fastened (75.7% in Indiana and 79.4% in Arizona). Most drivers were also aware of warning labels telling them to use their lap belt (63.9% in Indiana and 68.2% in Arizona). PMID- 9370011 TI - Fatal crashes of passenger vehicles before and after adding antilock braking systems. AB - Fatal crash rates of passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. Vehicles selected for analysis had no other significant design changes between the model years being compared, and the model years with and without antilocks were no more than two years apart. The overall fatal crash rates were similar for the two model years. However, the vehicles with antilocks were significantly more likely to be involved in crashes fatal to their own occupants, particularly single-vehicle crashes. Conversely, antilock vehicles were less likely to be involved in crashes fatal to occupants of other vehicles or nonoccupants (pedestrians, bicyclists). Overall, antilock brakes appear to have had little effect on fatal crash involvement. Further study is needed to better understand why fatality risk has increased for occupants of antilock vehicles. PMID- 9370012 TI - Effects of incentive programs to stimulate safety belt use: a meta-analysis. AB - The effects of campaigns using tangible incentives (rewards) to promote safety belt usage have been evaluated by means of a meta-analytic approach. Two coders extracted a total number of 136 short-term and 114 long-term effect sizes and coded many other variables from 34 journal articles and research reports. The results show a mean short-term increase in use rates of 20.6 percentage points; the mean long-term effect was 13.7 percentage points. Large scale studies report smaller effect sizes than small scale studies; when studies were weighted by the (estimated) number of observations, the weighted mean effect sizes were 12.0 and 9.6 percentage points for the short and long term, respectively. The main factors that influence the magnitude of the reported short-term effect of the programs were the initial baseline rate (which was highly correlated with the presence or absence of a safety belt usage law), the type of population involved, whether incentives were delivered immediately or delayed, and whether incentives were based on group or individual behaviour. Together these four variables accounted for 64% of the variance. Other variables, such as the duration of the intervention, the probability of receiving a reward, and the value of the reward were not related to the short-term effect sizes. The relationship between moderating variables and long-term effects was less clear. PMID- 9370013 TI - Driver age and traffic citations resulting from motor vehicle collisions. AB - This paper is an initial effort to examine whether driver age is related to the likelihood of receiving a traffic citation as a consequence of a crash. All crashes involving two motor vehicles in Wisconsin, 1991 were examined; additional information on any injuries resulting from a crash were obtained from hospital discharge records. Controlling for a variety of driver, vehicle and crash-related factors, these data suggest that the likelihood of receiving a citation is an increasing function of driver age. PMID- 9370014 TI - Lower limb injuries to passenger car occupants. AB - A detailed examination was undertaken of hospitalized car occupants who sustained a lower limb injury in a frontal crash. The assessment included an analysis of the type, severity and causes of these injuries and mechanisms involved in lower limb fractures. The findings showed that fractures and dislocations occurred in 88% of lower limb injury cases, that more than half were from crashes < 48 km hour-1 and that the number of fractures was directly proportional with delta V. Ankle dislocations and foot fractures from the floor and toe pand were the most common injury-source combination overall. The most frequent mechanisms of lower limb fracture were compression, perpendicular loading of the knee and crushing or twisting of the foot. The study points to the need for further regulation to reduce lower limb fractures in frontal crashes and highlights a number of possible countermeasures. PMID- 9370015 TI - Age related effects of restricted head movements on the useful field of view of drivers. AB - Eighty drivers in a sample of four groups of 20 (10 males, 10 females), aged under 30 years ('young'), 40-59 ('middle aged'), 60-69 ('older'), and 70 years and over ('oldest'), participated in tests of head rotation and of several visual functions relevant to safe driving. Head rotation data showed that the oldest drivers had lost about 1/3 of movement and that the loss tended to be more evident in males. Second attempts almost always produced slightly better results. All participants had at least 20/40 binocular vision, however, tests of monocular visual acuity, stereovision, and horizontal peripheral vision revealed that the poorest performers were aged 60 years and over and that the degree of decrement increased with age. Many of the older and oldest drivers in the sample were both severely restricted in their ability to turn their head and evidenced a loss of visual functioning. Analysis of the effect of reduced head movement on the useful field of view indicated that, for the drivers aged 60 years and over, there was an evident restriction on the distances at which approaching traffic could be brought into the central, stationary field, so that even at maximum head rotation plus one saccade (15 degrees), approaching vehicles would not be clearly perceived beyond a distance of 50 m. The findings are discussed in relation to older drivers' involvement in intersection accidents. PMID- 9370016 TI - Crash reductions related to traffic signal removal in Philadelphia. AB - The effect on intersection crashes of converting one-way street intersections in Philadelphia from signal to multiway stop sign control was estimated. Using crash and traffic volume data for a comparison group, regression models were computed to represent the normal crash experience of signal controlled intersections of one-way streets, by impact type, as a function of traffic volume. An empirical Bayesian procedure was used to estimate what would have been the expected number of crashes at the converted intersections had they not been converted. The empirical Bayesian estimates were compared with actual counts of crashes after conversion. Estimates were obtained for different classes of crashes categorized by impact type, day/night condition, and impact severity. Aggregate results indicate that replacing signals by multiway stop signs on one-way streets is associated with a reduction in crashes of approximately 24%, combining all severities, light conditions, and impact types. PMID- 9370017 TI - Serious brain injury from traffic-related causes: priorities for primary prevention. AB - This study evaluated the incidence and outcome of serious brain injury from traffic-related causes in 695 patients admitted to the Department of Neurosurgery at Karolinska Hospital during 1981-1992. A total of 37.3% of patients were car occupants, 28.1% pedestrians, 12.9% bicyclists, 12.2% car-bicycle/car-moped and 9.5% motorcycle riders. The dominating injury was brain contusion (61.6%) verified with computerized tomography. The level of consciousness was evaluated by the Glasgow Coma Scale (GCS) and outcome by the Glasgow Outcome Scale (GOS) at discharge and 6-36 months thereafter. The final outcome was 67.5% good recovery (GOS 4-5), 11.5% severely disabled (GOS 2-3) and 21.0% GOS 1 or brain dead. Patients with GOS < 4 (32.5%) were severely disabled and motivate priorities for injury prevention. Car occupants represent 40.7% of the total, followed by pedestrians at 33.6% and bicyclists at 18.2%. Much remains to be done in the primary prevention of disabling brain injury to car occupants and pedestrians. In order to achieve a more-effective primary prevention, future research should be directed toward biomechanical aspects of brain contusion as a dominating brain injury. PMID- 9370018 TI - Crash characteristics and injuries of victims impaired by alcohol versus illicit drugs. AB - Alcohol has long been associated with injury, but the relationship between other drugs and injury is less clear. Blood samples from 894 patients presenting to two Emergency Departments for treatment of motor vehicle injury sustained in passenger cars, station wagons, vans and pickup trucks, were tested for alcohol and other drugs. Results were related to demographic characteristics, including prior history of alcohol and drug use; crash characteristics; and injury characteristics. Alcohol was associated with more severe crashes, but other drugs, in the absence of alcohol, were not. The crashes involving drugs but no alcohol were very similar to those involving neither alcohol nor drugs. PMID- 9370019 TI - Modeling accident frequencies as zero-altered probability processes: an empirical inquiry. AB - This paper presents an empirical inquiry into the applicability of zero-altered counting processes to roadway section accident frequencies. The intent of such a counting process is to distinguish sections of roadway that are truly safe (near zero-accident likelihood) from those that are unsafe but happen to have zero accidents observed during the period of observation (e.g. one year). Traditional applications of Poisson and negative binomial accident frequency models do not account for this distinction and thus can produce biased coefficient estimates because of the preponderance of zero-accident observations. Zero-altered probability processes such as the zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) distributions are examined and proposed for accident frequencies by roadway functional class and geographic location. The findings show that the ZIP structure models are promising and have great flexibility in uncovering processes affecting accident frequencies on roadway sections observed with zero accidents and those with observed accident occurrences. This flexibility allows highway engineers to better isolate design factors that contribute to accident occurrence and also provides additional insight into variables that determine the relative accident likelihoods of safe versus unsafe roadways. The generic nature of the models and the relatively good power of the Vuong specification test used in the non-nested hypotheses of model specifications offers roadway designers the potential to develop a global family of models for accident frequency prediction that can be embedded in a larger safety management system. PMID- 9370021 TI - The importance of the time factor in fire and rescue service operations in Sweden. AB - The aim of the paper is to measure the benefits and costs for the society if the fire and rescue service is delayed by 5 and 10 min respectively. A 5 min longer turn-out time is often the difference between a full-time and a voluntary crew. A 10 min difference may represent what happens if a voluntary crew on the outskirts of the municipality is closed down and their services are taken over by the centrally located full-time staff. In Sweden a full-time staff costs USD 180,000 more per year and man on duty. When it comes to the costs of a longer turn-out time three items dominates: fires in buildings; road transport accidents; and drowning cases. These three account for 38% of the alarms but 97% of the damage increase if the rescue operation is delayed, whether it is for 5 or 10 min. For all these three items we have carried out calculations based on our own empirical material. To be allowed to fight fires using breathing apparatus Swedish legislation requires a minimum crew of five. For a municipality in Sweden with the average number and distribution of alarms a full time crew of five is not economically justifiable until it reaches a population of 30,000. PMID- 9370020 TI - Differences in traffic judgements between young and old adult pedestrians. AB - Older pedestrians have been shown to be over-involved in casualty crashes, compared to younger pedestrians, in recent reports. This study set out to investigate whether older pedestrians' road crossing behaviour might render them more vulnerable to crashes because of declines in their physical, sensory, perceptual or cognitive abilities. An initial 'blackspot' accident analysis highlighted the types of crashes in which older (and younger) adult pedestrians were involved and likely crossing actions. Road crossing behaviour was then systematically measured from unobtrusive video recordings of individual road crossings for a sample of younger and older pedestrians at several urban locations. On two-way undivided roads, older pedestrians crossed more frequently when there was closer moving traffic and generally adopted less safe road crossing strategies than their younger counterparts. On one-way divided roads, their crossing behaviour was considerably more safe and similar to that of younger pedestrians. The findings suggest that age-related perceptual and cognitive deficits may play a substantial role in many of the crashes involving older pedestrians. PMID- 9370022 TI - Practice profile differences among Swedish dentists. A questionnaire study with special reference to prosthodontics. AB - A questionnaire measuring differences in prosthodontic practice profiles was sent to 2100 Swedish dentists working as general practitioners. The response rate was 76%. Among the responders, 58% were men and 42% women. Fifty per cent were private practitioners, the other 50% being publicly employed. The practice profile variables showed a great variation, and several of the distributions differed with regard to sex and dental care system. The working hours per week the time spent on prosthodontics were on average higher for men than for women. Private practitioners more frequently worked in large communities and cities than did dentists working in the Public Dental Health Service. Practically all (98%) of the private practitioners used more than 75% of their clinical time on treating adults, compared with less than half of the dentists in the Public Dental Health Service. Male dentists reported higher percentage figures with regard to clinical time used for dental care of adults and for prosthodontic services than did female dentists. The figures for fixed prosthodontic service rates varied in the same manner. Fixed prosthodontic services were much more common in private practice than in the Public Dental Health Service, in which more removable dentures were made. Even though private practitioners used more time for prosthodontic services, they referred fewer patients to specialists in prosthodontics and consulted a specialist less often than did the dentists in the Public Dental Health Service. PMID- 9370023 TI - Pattern of self-administered paracetamol and codeine analgesic consumption after mandibular third-molar surgery. AB - Pattern of analgesic consumption after unilateral mandibular third-molar surgery was investigated in an open study in 201 patients. All patients were supplied with six analgesic tablets containing 500 mg paracetamol and 30 mg codeine. Instructions for use were given. A mean consumption of 4.9 tablets over the 1st week and 3.6 tablets the day of operation was found. Eight (4%) patients indicated inadequate or no effect of the medication. The remaining patients were able to control pain, to a level of one-third of maximum pain, by using from one to five tablets. One hundred and thirty-two (68%) patients followed instructions with regard to start of medication. No difference in mean tablet consumption was found between compliant patients and those who delayed the intake of the first analgesic dose by more than 1 h. Predictor analysis showed the most powerful predictors to be preoperative depth of the third molar and moderate or heavy smoking. Thirteen per cent explanatory power of all predictors together was found. PMID- 9370024 TI - Surface ultrastructure of intact and in situ chlorhexidine-treated human buccal cells. A method for scanning electron microscopy. AB - Air-dried and ethanol-fixed buccal epithelial cell smears from five subjects were observed by scanning electron microscopy. The mucous pellicle was precipitated as a smooth haze covering the cells, and outlines of bacteria were found embedded within it. Rinsing the preparations under running water gradually diminished the mucous pellicle but not the cell-adherent bacteria. A more complete dissolution of the pellicle was accomplished by washing the buccal epithelial cells before smearing. After a chlorhexidine mouthrinse the buccal cells appeared distorted, with only a few adherent bacteria. Three days after the rinsing, the denatured appearance still persisted on many cells, however, simultaneously with the emergence of undenatured epithelial cells with adherent bacteria. The method introduced in this study is useful to investigate the bacteria-mucus-epithelial cell interactions. A possible mode of antibacterial activity of chlorhexidine in vivo may be that it destroys bacterial adhesins. The substantivity of chlorhexidine in the oral cavity may be linked to the turnover rate of the oral epithelial cells. PMID- 9370025 TI - Dental caries and related factors in 88- and 92-year-olds. Cross-sectional and longitudinal comparisons. AB - Our aim was to compare two groups of 88- and 92-year-olds (n = 92 and n = 40), respectively, with regard to teeth, caries, and salivary and microbial conditions. Oral variables were analyzed in relation to functional capacity and use of cardiovascular agents and psychoactive drugs. Untreated root caries, plaque score, and counts of lactobacilli increased between the ages of 88 and 92 years (P < 0.01). Nine of the 24 longitudinally followed up subjects had lost 1-5 teeth over 4 years, and 17 subjects had developed new caries (DFS). The mean caries increment over 4 years was 1.3 coronal and 3.6 root surfaces, and new DFS per 100 surfaces at risk was 4.3 coronal and 17.5 root surfaces. Plaque score and final pH of buffer capacity increased (P < 0.05 and 0.01, respectively), whereas saliva flow, independent of gender, was unchanged. Use of cardiovascular agents and psychoactive drugs was associated with a deteriorated dental status. PMID- 9370026 TI - The effect of two sucrose diets on formation of dentin and predentin in growing rats. AB - The effect of two high-sucrose diets on dentinal caries, dentin formation, and the predentin width was studied in Sprague-Dawley rats. Rats were weaned at the age of 3 weeks and for 4 weeks fed a non-cariogenic commercial rat food (R36) for control, a high-sucrose Stephan-Harris (S-H) diet, or a new high-sucrose (sR36) diet in which most of the barley and wheat flour of the control R36 diet were replaced by sucrose. The areas of dentinal caries, the areas of dentin formation, and the width of predentin and dentin were quantified. Both high-sucrose diets induced dentinal caries, and both reduced dentin formation and increased the width of predentin compared with the control diet. Moreover, rats fed the S-H high-sucrose diet showed significantly greater progression of caries and reduction of dentin formation relative to rats fed the new high-sucrose diet, sR36. The high-sucrose diet thus was a substrate for caries-inducing microbes and a significant, but possibly not the exclusive, substrate for host modulation of odontoblast function. PMID- 9370027 TI - HLA-DR4 and number of mutans streptococci in saliva among dental students and staff. AB - Our aim was to corroborate previous findings that HLA-DR4 carriers are characterized by higher levels of mutans streptococci in saliva than are individuals expressing other HLA-DR types. Of 68 subjects (dental students, staff, and faculty) who were sampled for salivary counts of mutants streptococci, 13 subjects with the lowest counts of mutans streptococci and 15 subjects with the highest counts were selected for HLA-typing. Of the 13 who expressed HLA-DR4, 8 were heavily colonized by mutants streptococci. Although a trend towards a relationship was found between HLA-DR4 carriage and high levels of mutans streptococci, it was not statistically significant. In this selected population, knowledge of how to minimize the risk of caries and mutans streptococci level may have influenced the results. PMID- 9370028 TI - Association of residual ridge resorption with systemic factors in home-living elderly subjects. AB - Residual ridge resorption after loss of teeth is a multifactorial oral problem. To examine the association of residual ridge resorption with systemic factors, a cross-sectional study was made of 177 edentulous subjects (43 men and 134 women) aged 76, 81, and 86 years. Resorption in the mandibular and maxillary residual ridges was assessed from panoramic radiographs. The effects on residual ridge resorption of the age, gender, smoking, alcohol intake, body mass index, functioning in daily living, and certain systemic diseases of the subjects were investigated. After adjustment for age and duration of edentulousness, the elderly women had a greater amount of reduction in the mandibular residual ridge than the men (P < 0.001). When the resorption was classified into slight or moderate and severe resorptions, the elderly with asthma were at high risk of severe reduction in the edentulous mandible (odds ratio, 6.0; 95% confidence interval (CI), 1.3-28.2); the elderly women were at high risk of severe resorption in the edentulous mandible, with an odds ratio of 4.5 (95% CI, 1.2 17.1); an inverse association was found between alcohol intake and severe resorption in the edentulous maxilla (odds ratio, 0.4; 95% CI, 0.2-0.9). This study suggests that asthma due to corticosteroid treatment is to be considered a risk indicator for severe resorption of the edentulous mandible, alcohol intake in the elderly may be related to a lesser degree of resorption of the edentulous maxilla. Female gender is confirmed as a major factor resulting in mandibular atrophy. PMID- 9370029 TI - Oral status and prosthetic factors related to residual ridge resorption in elderly subjects. AB - Our earlier studies on edentulous elderly subjects have shown associations of severe resorption in the mandibular residual ridge with female gender and systemic diseases. The aim of this study was to examine whether other factors also were related to residual ridge resorption (RRR). Among 177 edentulous elderly subjects effects on RRR were investigated with regard to history of edentulousness and denture-wearing, the condition of the dentures and soft tissues, dental status of the opposing jaw, and oral hygiene habits. No significant association was found between degree of resorption and duration of edentulousness in either the mandible or the maxilla. RRR was related to denture quality (P < 0.05); however, severe resorption was not. In the maxilla previous use of removable partial dentures was a factor contributing to the resorption (odds ratio (OR), 2.4); flabby ridge was related to the severity of the resorption (OR, 2.4). This study showed local factors related to RRR more often in the maxilla than in the mandible, thus suggesting that severe resorption in the mandible is influenced more by systemic factors than by those investigated in this study. PMID- 9370030 TI - Dimensions of the Dental Fear Survey among patients with dental phobia. AB - The aims of this study were to analyze and assess dimensions of the Dental Fear Survey (DFS), which has been developed to measure dental fears and phobias. The present study of 313 dental-phobic individuals analyzed the DFS in a factor analysis using an exploratory (EFA) and a confirmatory (CFA) factor analysis to show dimensions and latent variables. The EFA showed a five-factor structure, with dimensions including items characterizing 'Avoidance of dental care', 'Physiologic arousal during dental treatment', 'Anticipatory anxiety while waiting for dental treatment', 'Fear of the injection needle', and 'Fear of the drill'. The total explained variance of the EFA was 63%. Although statistically significant, the CFA model showed a factor structure with 6 latent variables including a general dental fear factor loading on all 20 items together with the aforementioned 5 factors. In spite of the limitation in sample size and the significant test statistic for this 6-factor structure, the model was interpretable in its dimensionality. In conclusion, these factor analyses have shown a different factor structure of the DFS in this sample of dental-phobic individuals as compared with the dimensions reported from previous research in samples representing nonclinical populations. PMID- 9370031 TI - Prevention of temporomandibular disorder-related signs and symptoms in orthodontically treated adolescents. A 3-year follow-up of a prospective randomized trial. AB - Recommendations about the need for occlusal adjustment after malocclusion therapy are inconclusive. A total of 123 orthodontically treated healthy adolescents (88 girls, 35 boys; 14.8 +/- 1.7 years old) agreed to participate in the present study. The subjects were interviewed and examined for signs and symptoms related to temporomandibular disorder (TMD) and were randomly allocated to intervention (n = 63) and control (n = 60) groups. At base line, occlusal adjustment was carried out for the intervention group and repeated every 6 months thereafter as needed. Mock adjustments were performed for the control group. At the end of the 3rd year 118 subjects (96%) turned up for re-examination. The number of subjects with palpatory pain of the masticatory muscles, and with occlusal centric slides decreased significantly in the intervention group but not in the control group (P < 0.001). In conclusion, occlusal adjustment therapy may prevent the occurrence of TMD signs in orthodontically treated healthy adolescents. PMID- 9370032 TI - The need and demand for orthodontic treatment in 13- to 15-year-olds in Nairobi, Kenya. AB - The need for orthodontic treatment in Kenya was previously not been investigated. This study was undertaken to assess the need for orthodontic treatment in 13- to 15-year-old children in Nairobi. The objective need was assessed in 919 children by using the Norwegian treatment need index, and the subjective need was assessed in 739 children by using a structured questionnaire. Objective treatment need was recorded in 29% and subjective need in 33% of the children. Less than 1% were allocated the 'very great need' category. Relatively more girls than boys were dissatisfied with the appearance of their teeth, and a significantly higher number of girls (P < 0.001) said they would like to have their teeth straightened. The children's perceived need for treatment correlated significantly with the treatment need index. Fixed appliances were found necessary for correcting malocclusion in 23% of the children and removable appliances in 6%. Future studies in Kenya should be directed at determining the societal perception of malocclusion, upon which treatment standards may be based. PMID- 9370034 TI - Synthesis and hybridization properties of the conjugates of oligonucleotides and stabilization agents--II. AB - New pyranone derivatives having tri- or pentamethylenamine linker functions were synthesized. These derivatives were covalently attached through the 5' phosphoramide linkage to heptanucleotide pd(CCAAACA). Complementary complexes of the octanucleotide pd(TGTTTGGC) and above oligonucleotide conjugates were tested for their thermodynamic response. The Tm data and thermodynamic parameters for complex formation have demonstrated the ability of chromone (gamma-pyrone) and coumarin (alpha-pyrone) derivatives to stabilize strongly 7-mer/8-mer complementary complex, most likely through the stacking interaction of the pyran aromatic system with the neighboring nucleotide bases. The effect of chromone (or coumarin) derivatives on the stability of the oligonucleotide complexes (delta delta G at 37 degrees C ranged from -1.0 to -1.7 kcal/mol) was shown to be comparable to the effect of one nucleotide base pair and similar to the effect (delta delta G at 37 degrees C ranged from -1.5 to -2.0 kcal/mol) found for acridineoligonucleotide conjugates served in this study as a reference. PMID- 9370033 TI - The design, synthesis and transmembrane transport studies of a biomimetic sterol based ion channel. AB - A model sterol-based ion channel was rationally designed and synthesized. The potential ion channel is comprised of a tartrate-derived crown ether to which six steroids are appended. Macromolecule 1a was incorporated into phospholipid vesicles and shown to facilitate the transmembrane transport of sodium and lithium ions using alkali metal NMR spectroscopy. PMID- 9370035 TI - Isolation of new bioactive annonaceous acetogenins from Rollinia mucosa guided by liquid chromatography/mass spectrometry. AB - Reversed-phase high-performance liquid chromatography (RP-HPLC) fractionation, monitored by liquid chromatography/electrospray mass spectrometry (LC/ESI-MS), led to the isolation of two new bioactive annonaceous acetogenins, rollidecin C (1) and rollidecin D (2), from the bioactive aqueous methanol fraction of the leaves of Rollinia mucosa (Annonaceae). The structures were confirmed by analyses of the 1H and 13C NMR data. In addition, a known adjacent bis-tetrahydrofuran (THF) acetogenin, desacetyluvaricin (3), was isolated from this plant for the first time utilizing the LC/ESI-MS monitoring approach. Compound 1 exhibited selective cytotoxicity toward the colon tumor cell line (HT-29), while 2 showed only borderline cytotoxicity in a panel of six human tumor cell lines. PMID- 9370036 TI - Solid-phase synthesis of CD52 glycopeptide and an efficient route to Asn-core pentasaccharide conjugate. AB - The intact peptide sequence (18) as well as its glycoform carrying an N-linked core pentasaccharide (1) of CD52 antigen were prepared by means of solid-phase synthesis employing Fmoc-amino acids and benzyl-protected oligosaccharide asparagine conjugate (3) as building blocks. It was concluded that the pentasaccharide structure had little influence on further peptide elongation in solid-phase synthesis and the benzylated pentasaccharide moiety was sufficiently stable to the 95% TFA acidic conditions used to release glycopeptide from the supporting resin. The paper also describes an efficient route leading to asparagine-core pentasaccharide conjugate (3) which was prepared in seven steps for an overall yield of 23% from monosaccharide units 5, 6, 7 and 8. PMID- 9370037 TI - Stereochemical influence on the stability of radio-metal complexes in vivo. Synthesis and evaluation of the four stereoisomers of 2-(p-nitrobenzyl)-trans CyDTPA. AB - Distinct differences in in vivo stability of the two diastereomeric C Functionalized CyDTPA chelating agents, (CHX-A DTPA and CHX-B DTPA, both racemates), as recently reported prompted further investigation as to why differences in configuration produced striking effects on the in vivo stability of their yttrium complexes. To this end, the four individual component stereoisomers of CHX-A and CHX-B were synthesized and ability to bind yttrium was investigated both in vitro and in vivo. PMID- 9370038 TI - Inhibition of cathepsin G by 4H-3,1-benzoxazin-4-ones. AB - A series of 4H-3,1-benzoxazin-4-ones is reported that inhibit the serine proteases human cathepsin G and bovine chymotrypsin. The synthesis and kinetic parameters of the alkaline hydrolysis is described. These compounds act as acyl enzyme inhibitors of both enzymes. The reaction of cathepsin G with 2-benzylamino 4H-3,1-benzoxazin-4-one (20) was studied in detail. A partition in deacylation of the initially formed acyl-enzyme was observed, leading to the formation of 2-(3 benzylureido)benzoic acid (26) and 3-benzylquinazoline-2,4-(1H,3H)-dione (27). A 6-methyl substitution strongly increased the acylation rate of both proteases. Introduction of an aryl moiety into the 2-substituent led to compounds with Ki values towards cathepsin G in the nanomolar range. Their inhibitory potency is stronger than that of other synthetic inhibitors of cathepsin G. PMID- 9370039 TI - Structure of kainic acid totally elucidated by NMR and molecular modelling. AB - One class of glutamate receptors is characterized by the binding of the neuroexcitant and toxin kainic acid (KA), which contains an embedded L-glutamate moiety in a partially restricted (about the 2,3-bond) conformation. While there are a number of compounds that exhibit high specificity and selectivity at the ionotropic N-methyl-D-aspartate receptor, there has been a lack of selective and high-affinity ligands for the ionotropic KA subclass of excitatory amino acid receptors. This substance has received some attention recently being the least understood of the ionotropic type of glutamate receptor. The spatial orientation of the perceived functional groups of KA has been elucidated by a conformational analysis of an aqueous solution of KA using a combination of nuclear magnetic resonance (NMR) experimental results, mechanics and dynamics calculations, and theoretical simulation of NMR spectra. The weak pH-dependent effects on overall conformation and the structure of the principal '4E-envelope' KA conformer are established in aqueous solution. This study clearly shows the structural 'down' position of the double bond and the preferred 'g(-)-c' conformation of the C(3) carboxymethyl side-chain. The complex structure of this compound is thus definitively resolved. The conformation of the envelope ring such as C(3) carboxymethyl and C(4)-isopropenyl groups may strongly influence the potencies of KA interactions with the KA receptor. PMID- 9370040 TI - Preparation, antimicrobial evaluation, and mutagenicity of [2-hydroxyaryl]-[1 methyl-5-nitro-1H-2-imidazolyl]methanols , [5-tert-butyl-2-methylaminophenyl]-[1 methyl-5-nitro-1H-2-imidazo lyl]me thanol, and [2-hydroxyaryl]-[1-methyl-5-nitro 1H-2-imidazolyl] ketones. AB - Efficient preparations of the titled compounds are described, their antimicrobial activity and mutagenic properties being evaluated. Some of the studied compounds are nonmutagenic and present a MIC as low as some of the usual standards in the field. PMID- 9370041 TI - Structure-binding relation of philanthotoxins from nicotinic acetylcholine receptor binding assay. AB - Philanthotoxins are noncompetitive inhibitors of the nicotinic acetylcholine receptor and the various glutamate receptors. Analogues carrying photoaffinity labels, fluorine atoms for solid-state NMR studies of ligand/receptor interaction, and large head groups such as porphyrins and planar bulky aromatic rings (BIG analogues) for clarifying mode of entry and orientation of analogues in receptors have been synthesized, assayed against the nicotinic acetylcholine receptor, and brief comments are given for the assay results. PMID- 9370042 TI - A new type of carboxypeptidase A inhibitors designed using an imidazole as a zinc coordinating ligand. AB - 2-(4-Imidazoyl)hydrocinnamic acid (1) and its congeners (2-4) having different length of alkyl chain spacers between the imidazole ring and the alpha-carbon to the carboxylate of 1 have been designed, synthesized and evaluated as inhibitors for carboxypeptidase A to show that they are competitive inhibitors for the enzyme. Inhibitor 1 was most potent having the Ki value of 0.8 microM. The present study demonstrates that imidazole ring is an effective zinc coordinating ligand that can be useful for the design of inhibitors for zinc proteases. PMID- 9370043 TI - Chronic lymphocytic leukaemia: the nature of the leukaemic cell. AB - Far from being the boring, inactive, inert lymphocyte that haematologists of old perceived it to be, the chronic lymphocytic leukaemia (CLL) cell has set us many complex problems. The cell is apparently stuck in G0 in cell cycle, yet expresses many activation markers. The cells apparently manufacture many cytokines and respond in vitro to even more, yet cells entering even G1 are few. The cell surface marker profile is unique. There is apparently no normal equivalent of the CLL cell. In part, this may be because the cell is malignant; malignant cells often express aberrant markers. Consistent chromosomal abnormalities are emerging but we have no idea how these abnormalities translate into molecular mistakes that dictate the peculiar nature of the cell. CLL cells carry a characteristics set of adhesion molecules, but we cannot read their homing and recycling instructions. The outstanding irregularities of the CLL cell are its CD5 positivity and its sparse surface immunoglobulin. This ought to translate as an anergic B1 cell, perhaps programmed for autoimmunity. If the tumour cell were responsible for the patient's production of immunoglobulin or secretion of autoantibodies, then a pattern might have emerged. Alas, these are the product of the normal B cells. How the CLL cell induces these complications is unknown. Thus, despite the information contained in this review, the CLL cell remains a puzzle. PMID- 9370044 TI - Clonal eosinophilic disorders and the hypereosinophilic syndrome. AB - An increase in the blood eosinophil count may occur in a number of disease states including allergies, parasitic infections, vascular disease and as a reaction to the presence of malignant tumours. This article defines those disorders that are not purely reactive, and describes in detail the diagnosis and features of clonal eosinophilic disorders and the hypereosinophilic syndrome. The clonal disorders that are associated with eosinophilia are discussed, in particular the acute and chronic eosinophilic leukaemias and clonal eosinophilias in association with acute myeloid leukaemia, myeloproliferative disorders and myelodysplastic syndromes. Whether eosinophilia is produced by a clonal or reactive disorder, the end result can often be the same, i.e. end organ damage produced by sustained hypereosinophilia in the presence of eosinophil activation. When no cause for the eosinophilia leading to the end organ damage is found, this disease is termed 'idiopathic hypereosinophilic syndrome'. Its pathogenesis, clinical features and management are discussed with particular reference to the possibility of it being a T-cell-associated disorder. PMID- 9370045 TI - Use of radioactive phosphorus in haematology. AB - Following the development of the cyclotron in 1932, radio-isotopes became available for use in medicine both as tracer substances and therapeutic agents. The father of nuclear medicine, Dr J. H. Lawrence, pioneered their use in a range of disease states and found that radio-isotopes were of enormous value in the diagnosis and treatment of haemopoetic disease, particularly the myeloproliferative disorders. Radioactive phosphorus 32P emerged as the radio isotope of choice for the myelosuppressive treatment of myeloproliferative disorders. This article also describes the use of radio-isotopes in the treatment of other disorders: chronic myeloid leukaemia, chronic lymphocytic leukaemia and myeloma, work that is now largely forgotten. All myeloproliferative disorders may evolve without treatment into myelodysplastic syndrome or blast-cell transformation. It is accepted that life is prolonged in myeloproliferative disorders treated with 32P or alkylating agents, yet both are leukaemogenic. The ideal form of treatment for polycythaemia vera is unknown and will remain so, for patients with this disorder often outlive their physician and achieve 90% of normal life expectation. 32P remains the treatment of choice for elderly patients with polycythaemia vera. PMID- 9370046 TI - Stem-cell mobilization for autografting in chronic myeloid leukemia. AB - In this article, the rationale for autografting in chronic myeloid leukemia is reviewed, and alternative therapeutic approaches to the use of granulocyte-colony stimulating factor and chemotherapy-mobilized peripheral blood stem cells are discussed. The data from patients treated using the original ICE (idarubicin, cytarabine, etoposide), or the shorter course mini-ICE protocols are considered, with special emphasis on those patients who received their chemotherapy regimens soon after diagnosis and prior to any treatment with interferon alpha. The appropriate design of a trial to test the value of autografting in chronic myeloid leukemia is discussed, as is the optimal timing of collections to achieve the maximal yield and purity of Ph-negative peripheral blood stem cells. PMID- 9370047 TI - Clinical erythrokinetics: a critical review. AB - The hemoglobin concentration and the hematocrit percentage are usually used to diagnose anemias and erythrocytoses and to monitor their treatment and progress. However, they may be misleading because of dehydration or dilution and it is imperative to keep in mind their relationship to the size of the red-cell mass. This size is determined by the cellular kinetics of four distinct compartments which make up the erythron: the stem cells, the progenitor cells, the precursor cells and the mature cells. Under normal physiologic conditions, the kinetics of the progenitor-cell compartment determines the size of the red-cell mass but, under abnormal conditions, the kinetics of each of the compartments may affect the size. In this review, normal and abnormal kinetics of the four compartments are defined and related to the size of the red-cell mass and the pathogenesis of anemias and erythrocytoses. PMID- 9370048 TI - Regulation of blood pressure with calcium-dependent dopamine synthesizing system in the brain and its related phenomena. AB - The effects of calcium on blood pressure regulation remain controversial. Although the mechanism by which calcium increases blood pressure when it is given intravenously and acutely has been elucidated, that by which calcium reduces blood pressure when it is supplemented chronically and slightly through daily diet is unclear. From a number of animal experiments concerning the effects of calcium on blood pressure, we believe that calcium ions have two separate roles in the regulation of blood pressure through both central and peripheral systems: (1) calcium ions reduce blood pressure through a central, calcium/calmodulin dependent dopamine-synthesizing system and (2) calcium ions increase blood pressure through an intracellular, calcium-dependent mechanism in the peripheral vasculature. These concepts were applied to elucidate the mechanisms underlying hypertension in spontaneously hypertensive rats (SHR) and changes in blood pressure in other experimental animals, and the following conclusions were reached. The decrease of the serum calcium level in spontaneously hypertensive rats (SHR) causes a decrease in calcium/calmodulin-dependent dopamine synthesis in the brain. The subsequent low level of brain dopamine induces hypertension. The increase in susceptibility to epileptic convulsions and the occurrence of hypertension in epileptic mice (El mice) may be linked through a lowering of calcium-dependent dopamine synthesis in the brain, and epilepsy and hypertension may be associated. Exercise leads to increases in calcium-dependent dopamine synthesis in the brain, and the increased dopamine levels induce physiological changes, including a decrease in blood pressure. Cadmium which is not distinguished from calcium by calmodulin, activates calmodulin-dependent functions in the brain, and increased dopamine levels may decrease blood pressure. In this report, our studies are considered in light of reports from many other laboratories. PMID- 9370049 TI - Methodological considerations of intracerebral microdialysis in pharmacokinetic studies on drug transport across the blood-brain barrier. AB - For the study of the pharmacokinetics of drugs in the brain a number of in vivo techniques is available, including autoradiography, imaging techniques, cerebrospinal fluid sampling and in vivo voltammetry, which all have their specific advantages and limitations. Intracerebral microdialysis is a relatively new in vivo technique. It permits monitoring of local concentrations of drugs and metabolites at specific sites in the brain which makes it an attractive tool for pharmacokinetic research. In the use of this technique a number of factors should be considered. These include: type of probe, surgical trauma, post-surgery interval, perfusion flow rate, as well as composition and temperature of the perfusion medium. In particular in studies on drug transport across the blood brain barrier (BBB), effects of insertion of the probe on BBB functionality is important. It appears that BBB functionality is not significantly affected if surgical and experimental conditions are well-controlled. The relationship between dialysate concentrations and those in the extracellular fluid of the periprobe tissue, the recovery of the drug, depends on periprobe processes governing the actual concentration of the drug at that site. These include extracellular-microvascular exchange, metabolism, and diffusion of the drug. Several methods have been proposed to determine recovery values. In particular the no net flux method and the extended no net flux method are useful in practice. Several microdialysis studies on BBB transport of drugs are presented showing that intracerebral microdialysis is capable to assess local BBB transport profiles. Compared with other in vivo techniques, intracerebral microdialysis is the only (affordable) technique that offers the possibility to monitor local BBB transport of drugs in unanaesthetized animals, under physiological and pathological conditions. PMID- 9370050 TI - Cholinergic activity and amyloid precursor protein metabolism. AB - With more than 4 million Alzheimer's victims nationwide, there is intense research to elucidate the relationship among the hallmarks of the disease, amyloid plaques, neurofibrillary tangles, and degeneration of the basal forebrain cholinergic neurons. There has been much debate about which of these is the primary lesion, and which develops secondarily. The correlation between plaques and tangles and dementia is not absolute, but a consistent feature of Alzheimer's disease is loss of cortical and hippocampal cholinergic function as a result of basal forebrain compromise. Additionally, factors associated with the cholinergic system have been shown to influence the processing and metabolism of the amyloid precursor, a protein that contains the amyloidogenic sequence found in plaques. In this paper, the relationship between cholinergic compromise and amyloid deposition, as well as the cholinergic system-associated factors which appear to participate in amyloid precursor protein processing, are discussed. PMID- 9370051 TI - Animal models of cerebral beta-amyloid angiopathy. AB - Cerebral amyloid angiopathy (CAA) is a significant risk factor for hemorrhagic stroke in the elderly, and occurs as a sporadic disorder, as a frequent component of Alzheimer's disease, and in several rare, hereditary conditions. The most common type of amyloid found in the vasculature of the brain is beta-amyloid (A beta), the same peptide that occurs in senile plaques. A paucity of animal models has hindered the experimental analysis of CAA. Several transgenic mouse models of cerebral beta-amyloidosis have now been reported, but only one appears to develop significant cerebrovascular amyloid. However, well-characterized models of naturally occurring CAA, particularly aged dogs and non-human primates, have contributed unique insights into the biology of vascular amyloid in recent years. Some non-human primate species have a predilection for developing CAA; the squirrel monkey (Saimiri sciureus), for example, is particularly likely to manifest beta-amyloid deposition in the cerebral blood vessels with age, whereas the rhesus monkey (Macaca mulatta) develops more abundant parenchymal amyloid. These animals have been used to test in vivo beta-amyloid labeling strategies with monoclonal antibodies and radiolabeled A beta. Species-differences in the predominant site of A beta deposition also can be exploited to evaluate factors that direct amyloid selectively to a particular tissue compartment of the brain. For example, the cysteine protease inhibitor, cystatin C, in squirrel monkeys has an amino acid substitution that is similar to the mutant substitution found in some humans with a hereditary form of cystatin C amyloid angiopathy, possibly explaining the predisposition of squirrel monkeys to CAA. The existing animal models have shown considerable utility in deciphering the pathobiology of CAA, and in testing strategies that could be used to diagnose and treat this disorder in humans. PMID- 9370052 TI - The role of thrombin-like (serine) proteases in the development, plasticity and pathology of the nervous system. AB - There is increasing evidence suggesting that members of the serine protease family, including thrombin, chymotrypsin, urokinase plasminogen activator, and kallikrein, may play a role in normal development and/or pathology of the nervous system. Serine proteases and their cognate inhibitors have been shown to be increased in the neural parenchyma and cerebrospinal fluid following injury to the blood brain barrier. Zymogen precursors of thrombin and thrombin-like proteases as well as their receptors have also been localized in several distinct regions of the developing or adult brain. Thrombin-like proteases have been shown to exert deleterious effects, including neurite retraction and death, on different neuronal and non-neuronal cell populations in vitro. These effects appear to be mediated through cell surface receptors and can be prevented or reversed with specific serine protease inhibitors (serpins). Furthermore, we have recently shown that treatment with protease nexin-1 (a serpin that inhibits thrombin-like proteases) promotes the survival and growth of spinal motoneurons during the period of programmed cell death and following injury. Taken together, these observations suggest that thrombin-like proteases play a deleterious role, whereas serpins promote the development and maintenance of neuronal cells. Thus, changes in the balance between serine proteases and their cognate inhibitors may lead to pathological states similar to those associated with some neurodegenerative diseases such as Alzheimer's disease. The present review summarizes the current state of research involving such serine proteases and speculates on the possible role of these thrombin-like proteases in the development, plasticity and pathology of the nervous system. PMID- 9370053 TI - Important role for angiotensin III and IV in the brain renin-angiotensin system. AB - Considerable evidence now suggests that the precursors and enzymes necessary for the formation and degradation of biologically active forms of angiotensins are present in brain tissues, accompanied by at least three specific binding sites. It also appears that several forms of angiotensin may serve as signaling agents at these sites. There is accumulating support for the notion that AngII must be converted to AngIII in order to bind at the AT1 and AT2 receptor subtypes, and AngIII must be converted to AngIV in order to activate the AT4 receptor subtype. Further, AngII(1-7) may activate a separate binding site concerned with antidiuresis, however, characterization of this site has not been completed. The AT1 site appears to mediate the classic angiotensin functions concerned with body water balance, maintenance of blood pressure, and cyclicity of reproductive hormones and sexual behaviors. This receptor site also exerts some control over the secretion of pituitary hormones. Less is known about the functional importance of the AT2 site, however, it has been implicated in vascular growth, control of blood flow, and perhaps modulation of NMDA receptors. The AT4 site is heavily distributed in neocortex, hippocampus, cerebellum, and basal ganglia structures, as well as several peripheral tissues. This site appears to mediate memory acquisition and retrieval, the regulation of blood flow, neurite outgrowth, angiogenesis, and kidney function. In addition to the well-studied functions of the brain renin-angiotensin system, additional less well investigated responses are reviewed. These include electrophysiological activation, tachyphylaxis, long term potentiation, learning and memory, and cognitive affect. PMID- 9370054 TI - Behavioral, anatomical, and physiological aspects of recovery of motor function following stroke. AB - Restoration of motor function is relatively common in humans and non-human primates. Studies of the behavioral aspects of recovery indicate that responses re-emerge in a fixed sequence that resembles initial acquisition. The extent to which this occurs depends on factors unique to the subject. Research suggests that the traditional view of a hierarchically organized brain is inaccurate. Instead, the brain is comprised of parallel circuits which may be disinhibited and/or recruited when damage occurs. In some cases, damage leads to reorganization of cerebral cortical maps. Available data point to the utility of interventions to promote recovery. Research suggests that recovery from other forms of impairment (e.g., non-vascular lesions or impairment in language) involves similar processes. PMID- 9370055 TI - The effects of 'sleep promoting agents' on behavioural state in the ovine fetus. AB - Fetal behavioural states, with similarities to adult sleep states, exist in both the human and ovine fetus near term. The purpose of the present study was to determine the effects of intracerebral administration of pharmacologic agents, known to affect sleep states in the adult, on fetal behavioural states and physiologic correlates using the chronically catheterized ovine fetus near term. Each drug was infused into either the cisterna magna or lateral ventricle for 90 min in one of two doses. Carbachol (1.35 x 10(-5) and 4.25 x 10(-6) M) led to an increase in low-voltage ECOG, eye movement and FBM activities, while scopolamine (4.68 x 10(-4) and 1.56 x 10(-4) M) led to a decrease in low-voltage ECOG and eye movement activity with an increase in high-voltage ECOG activity. L-5 Hydroxytryptophan (5-HTP) (2.04 x 10(-3) and 6.81 x 10(-4) M) infusion led to an increase in FBM, while VIP (3.00 x 10(-7) and 1.00 x 10(-7) M) infusion had no effect on fetal behavioural state parameters. Study results indicate that fetal behavioural states can be altered pharmacologically and in a manner similar to that seen in the adult but with notable differences that may relate to species, developmental or dose-response issues. PMID- 9370056 TI - Calcium-binding proteins in the substantia nigra and ventral tegmental area during development: correlation with dopaminergic compartmentalization. AB - The importance of calcium in neuronal function has been amply demonstrated in recent years. The discovery of a class of proteins within neurons which bind calcium, therefore, has proven to be a catalyst for the generation of theories and hypotheses regarding mechanisms of neurotoxicity in the CNS. In addition, the distribution of certain calcium-binding proteins changes during neural development, suggesting that they may play a role in organization or pattern generation. We have examined the ontogeny of three related calcium-binding proteins, calbindin-D28, parvalbumin and calretinin, with respect to the ventral and dorsal compartments or tiers of the dopaminergic population in the ventral midbrain. Single and dual-label immunocytochemistry was employed to map the distributions of calcium-binding proteins and tyrosine hydroxylase from E18 through adulthood. The results show that each of the three proteins exhibits a unique developmental sequence and compartment preference, with calbindin D28 clearly related to the later-developing dorsal tier, and parvalbumin and calretinin to the ventral tier of the dopaminergic ventral mesencephalon. PMID- 9370057 TI - Maternal protein restriction early in rat pregnancy alters brain development in the progeny. AB - We assessed the effects of a dietary protein restriction (5% vs. 20% casein in diet) initiated at conception and imposed during the first 2 weeks of rat gestation on postnatal brain development. At the end of the malnutrition period, protein-restricted animals exhibited significantly smaller fetal body weight and brain cortical thickness than controls. At birth and thereafter, body weight was normalized in the progeny. Similarly, brain weight and cytoarchitecture were normal in postnatal animals. In contrast, we observed, during the first 2 postnatal weeks, several abnormalities of brain development which affected all the studied areas for most of the studied parameters: (i) delayed astrocytogenesis as shown by a reduced GFAP staining; (ii) delayed production of hyaluronan in the extracellular matrix studied with binding of biotinylated hyaluronectin; (iii) abnormal neuronal differentiation as shown by reduced expression of MAP-5 and increased expression of MAP-1; (iv) abnormal synaptogenesis as shown by the increased expression of synaptophysin in the basal ganglia; (v) decreased programmed cell death. In adult prenatally protein restricted animals, all the above parameters were normalized excepted MAP-1 labeling which remained high. In addition, we observed slight alterations of the ventilatory response to hypoxia in adult animals. The present study demonstrates that early protein malnutrition during embryonic development induces multiple, transient alterations of brain development. However, the almost complete normalization in adults of brain architecture and differentiation as well as our physiological data strongly suggest a remarkable plasticity of the developing brain following an early aggression. PMID- 9370058 TI - Differential expression of calretinin, calbindin D28K and parvalbumin in the developing human cerebellum. AB - Three calcium-binding proteins, calretinin, calbindin D28K and parvalbumin, were immunohistochemically localized in the human cerebellum at different developmental stages. Cells positive for calretinin were not detected during early development of the cerebellum until 21 weeks of gestation at which stage weak staining was found in Purkinje and basket cells of the cortex and in neurons of the dentate nucleus. Both the number of positive cells and the intensity of immunoreactivities were found to increase as the cerebellum became more mature. Calbindin D28K immunoreactivity was, however, detected early in development at 14 weeks of gestation. Positive cells were found in Purkinje, basket, stellate and granule cells of the cerebellar cortex and in neurons of fastigial, globose, emboliform and dentate nuclei. The number of positive cells and the staining intensity for calbindin in both the cerebellar cortex and deep nuclei decreased at more advanced developmental stages. At 21-31 weeks of gestation, positive staining was restricted to Purkinje and basket cells of the cortex. Parvalbumin immunoreactivity was also observed early in development at 14 weeks of gestation. Positivity was found in Purkinje, basket and stellate cells of the cerebellar cortex and in neurons of all the deep nuclei, with the highest number of positive cells in the fastigial nucleus followed by emboliform, globose and dentate nuclei. As the cerebellum became more mature, both the number of positive cells and the staining intensity for parvalbumin decreased in the cortex and deep nuclei. The results of the present study showed that among the three calcium binding proteins examined, strong immunoreactivities for calbindin D28K and parvalbumin were found inthe human cerebellum early in development at 14 weeks of gestation, but there was a decrease in both the intensity and number of positive cells at more advanced stages. In contrast, calretinin positive cells were not detected until 21 weeks of gestation and the immunoreactivity increased as the cerebellum became more mature. A possible correlation between the developmentally regulated expression of the calcium-binding proteins and expression of different neurotransmitters during development is discussed. PMID- 9370059 TI - Developmentally regulated markers in the postnatal cervical spinal cord of the opossum Monodelphis domestica. AB - The aim of this study was to identify developmentally regulated immunocytochemical markers to assess development in the cervical spinal cord of Monodelphis domestica. We demonstrate that two commercially available antibodies exhibit altered patterns of distribution during early postnatal development. Although neurofilament staining was present at birth, only the phosphorylated form, recognised by monoclonal antibodies 2F11 or SMI31 could be detected. Non phosphorylated neurofilament, recognised by monoclonal antibody SMI32, only became detectable around postnatal day 4 (P4) but was restricted to cells in the ventral horn until 5 weeks postnatum. By 7.5 weeks, SMI32 immunoreactivity (IR) was found throughout the grey matter in a pattern similar to that in the adult for both SMI32 and microtubule-associated protein 2 (MAP2). The intermediate filament proteins, glial fibrillary acidic protein (GFAP) and vimentin (VIM), were detectable at birth in radially oriented, fibrous cells, but GFAP-IR was restricted to the ventral half of the cord. This ventral to dorsal gradient of GFAP-IR diminished during the first week of postnatal life, disappearing by P8. Many astrocyte-like, GFAP-positive cells were clearly present by 38 days and, in the adult, were abundant in the white matter. A few VIM-IR cells remained in the adult cord, also within the white matter. We suggest that SMI32 and GFAP are useful, developmentally regulated markers for studies of opossum spinal cord development. We are currently using these markers to investigate the pronounced rostral to caudal gradient in the postnatal spinal cord and to assess development in the cultured spinal cord. PMID- 9370060 TI - Changes in brain glucose levels and glucose transporter protein isoforms in alcohol- or nicotine-treated chick embryos. AB - Suppression of fetal brain growth during pregnancy as the result of maternal smoking or alcohol consumption leads to significant problems for the offspring as well as for the society who must care for these individuals. Chronic maternal intake of cigarette smoke is frequently observed in humans and studies using animal models suggest that in utero nicotine exposure is an important component of the growth suppression that results. Similarly, maternal consumption of alcohol (ethanol) has a profound, negative effect on fetal growth. The developing fetal central nervous system (CNS) is sensitive to the growth inhibitory effect of nicotine or alcohol and morphological as well as functional CNS deficits may result from fetal exposure. Using an embryonic chick model which minimizes drug induced changes in maternal nutrition and behavior, the studies presented here indicate that nicotine or alcohol exposure during early embryonic development inhibits brain growth to a degree comparable to that seen in the rest of the organism, i.e., there was no 'brain sparing' in this model. Glucose content per milligram tissue was markedly decreased in brains of the nicotine-treated embryos but was not significantly different in the alcohol-exposed embryos. Western blots of fetal brain glucose transporter protein isoforms showed no change in the Glut 3 transporter content in the growth suppressed brains compared to vehicle-treated brains. The Glut 1 55 kilodalton (kd) isoform protein content was significantly decreased in the nicotine-treated brains but unchanged in the ethanol-treated brains, while the reverse was true for the Glut 1 45 kd isoform. Thus, the changes in the 55 kd isoform protein content were correlated with tissue glucose levels in the ethanol- and nicotine-treated embryos. PMID- 9370061 TI - Variations in oxidative enzyme type profiles among prenatal rat lumbar motoneurons. AB - We have used cytochrome oxidase histochemical staining to evaluate whether immature rat lumbar motoneurons show intrinsic separation into high or low oxidative enzyme types. Relative oxidative enzyme levels are frequently used to help differentiate between muscle fibres of various types and to differentiate between mature neurons. Here we show a wide variation in motoneuron cytochrome oxidase levels from prenatal times, although the range of staining levels as measured densitometrically is greater for mature than for prenatal animals. We find variation in cytochrome oxidase levels among motoneurons prior to the formation of mature patterns of connectivity or electrical activity, and conclude therefore that this differentiation is unlikely to have arisen by differential usage and probably arose as a function of cell lineage. PMID- 9370062 TI - A splice variant of Dp71 lacking the syntrophin binding site is expressed in early stages of human neural development. AB - Dp71, a 71 kDa C-terminal isoform of dystrophin, is the major product of the DMD gene in brain. Two alternatively spliced transcripts of Dp71 were amplified by RT PCR from different areas of human fetal neural tissue. Both transcripts were spliced out of exons 71 and 78. The shorter transcript was also alternatively spliced of exons 72-74, a region comprising the coding sequence for the binding site to syntrophin, one component of the dystrophin-associated protein complex. Results indicate that alternatively spliced forms of Dp71 are regulated during human neural development. PMID- 9370063 TI - Exposure to light prior to hatching induces asymmetry of receptor binding in specific regions of the chick forebrain. AB - This paper describes neurochemical asymmetries present in forebrain regions of the newly hatched chick that result from environmental conditions; specifically from asymmetrical exposure of the chick embryo to light prior to hatching. Quantitative autoradiography was used to determine GABA and glutamate receptor subtype binding in a number of regions of the left and right forebrain hemispheres of chicks that had either the left (LES), or the right (RES), eye system exposed to light prior to hatching. On day 19 of incubation the embryo's head was withdrawn from the egg and the left or the right eye was occulded until hatching. [3H]MK-801, [3H]AMPA and [3H]muscimol binding assays were performed on frozen sections from 2 different coronal regions of the forebrain, sampled on day 1 posthatching. Significant [3H]MK-801, [3H]AMPA and [3H]muscimol binding asymmetries were determined in forebrain regions from chicks that had their RES exposed to light prior to hatching, particularly in forebrain regions which are known to receive afferent visual input. The reverse pattern of asymmetry was found for all 3 ligands in regions such as the ectostriatum of chicks that had their LES exposed to light, while asymmetry of muscimol and AMPA binding, present in many regions in right eye system chicks was not present in chicks that had the left eye system exposed to light during incubation. Thus, the presence and pattern of experience-dependent neurochemical asymmetries in the chick forebrain are specific to both region and receptor type. PMID- 9370064 TI - Adrenal steroids suppress granule cell death in the developing dentate gyrus through an NMDA receptor-dependent mechanism. AB - Treatment with the NMDA receptor antagonist MK-801 prevented the adrenal steroid induced suppression of cell death, determined by both morphological identification of pyknotic cells and TUNEL staining, in the dentate gyrus in rat pups. This finding suggests that adrenal steroids naturally promote granule cell survival via NMDA receptor activation. PMID- 9370065 TI - Expression of potassium channels in gerbil outer hair cells during development does not require neural induction. AB - Mammalian outer hair cells (OHCs) contain Ca and K channels in their synaptic pole. We questioned if the ontogeny of potassium currents of OHCs depends on the neural induction of early afferent contact. By recording whole-cell currents of OHCs grown in organotypic cultures deprived of afferent innervation, we show that a Ca-activated K channel is expressed in these cells, suggesting that the ontogeny of the K channel is an intrinsic process. PMID- 9370066 TI - The regional vulnerability to blockade of action potentials in organotypic hippocampal culture. AB - We investigated how blockade of spontaneous action potentials influenced the synaptogenesis by measuring the field population spike using hippocampal organotypic cultures. Although respective blockade of inhibitory and excitatory neurotransmission by picrotoxin and CNQX did not significantly induce cell death in all hippocampal area, sodium channel blocking drugs (tetrodotoxin or lidocaine) caused specific and severe damage and affected the formation of functional synapse in CA1 and the entorhinal cortex but not in CA3. It is suggested that the spontaneous action potentials would play a critical role during synaptogenesis. PMID- 9370067 TI - Urodynamic and cardiovascular measurements in patients with micturition syncope. AB - We describe the findings of urodynamic studies, together with blood pressure and heart rate monitoring, in five patients with micturition syncope. All patients had almost normal storage and evacuation function and no evidence of prostate hypertrophy. Conventional head-up tilt testing with an empty urinary bladder caused no change in arterial blood pressure, but a moderate increase in heart rate. Urinary bladder filling caused minimal increases of the arterial pressure and heart rate. The sitting posture with a distended bladder caused mild orthostatic hypotension. Urinary bladder evacuation caused a fall in arterial pressure with a decrease in heart rate. These responses were similar to those described in vasovagal syncope. The central mechanism for the initiation of urinary evacuation, or sensory input from the lower urinary tract, may trigger micturition syncope. PMID- 9370068 TI - Postural hypotension in a patient with cervical myelopathy due to craniovertebral anomaly. AB - We report a patient with craniovertebral anomaly leading to cervical cord compression who presented with disabling postural hypotension. A 60-year-old electrician presented with progressive weakness of the upper and lower limbs, which had started 7 years previously. He had difficulty in holding urine for the previous year and had blacked out on standing for the past 3 months. He had upper limb wasting and lower limb spasticity, with impaired joint position sense. Autonomic dysfunctions included postural hypotension, absence of sinus arrhythmia, impaired Valsalva ratio, and lack of increase in blood pressure on cold immersion and isometric contraction. Cervical spine radiograph and magnetic resonance imaging revealed atlantoaxial dislocation, Klippel-Feil syndrome and osteophytes, resulting in cord compression at C2-C4. Partial and selective damage to the descending autonomic fibres may be responsible for postural hypotension in this patient. PMID- 9370069 TI - Recent advances in breast cancer biology. AB - As medicine enters the 21st century, the field of breast cancer continues to reflect both our greatest successes and our greatest challenges as scientists, epidemiologists, and clinicians. Discoveries in the areas of breast cancer biology and genetics continue to help us refine our approach to the newly diagnosed patient as well as guide our development of cancer prevention and early detection strategies. This review highlights some of the recent advances in breast cancer biology, with an emphasis on dysregulation of the cell cycle, inherited cancer susceptibility, and tumor-related alterations of growth regulation and signal transduction pathways. PMID- 9370070 TI - Epidemiology, prevention, and early detection of breast cancer. AB - Breast cancer is a leading women's health issue. Continued advances in understanding the temporal sequencing of relevant exposures promises to shed light on the continuum of breast carcinogenesis. Oral contraceptive use and the transient increase in risk following childbirth are exposures that affect the near-term risk of breast cancer. The availability of commercial testing for inherited susceptibility to breast cancer has accelerated the need for data to develop sound policy for implementing gene testing. The risks associated with BRCA1 and BRCA2 mutations may be less than previously estimated. Antiestrogens with lesser risks than tamoxifen hold promise for chemoprevention, but await testing. Not enough is known to formulate primary prevention strategies based on lifestyle interventions. Further understanding lifestyle factors that may be involved in the etiology of breast cancer and are amenable to preventive intervention thus remains a top priority, with diet and physical activity of greatest interest. PMID- 9370071 TI - Pathology of preinvasive and excellent-prognosis breast cancer. AB - Our review of recent developments in breast cancer involving evaluation of cellular and tissue samples is targeted at indicators of elevated risk of sufficient magnitude to attain clinical significance; lesions unassociated with metastatic capacity but of sufficient risk to attain that capacity that formal treatment is necessary, ie, ductal carcinoma in situ; and indicators of good prognosis in invasive cancer. Ductal carcinoma in situ has been the subject of much recent discussion. We highlight particularly the area of stratification or classification within this group of lesions. The importance of the extensiveness of ductal carcinoma in situ in the prediction of local recurrence within the conserved breast is included. Also discussed are advances in diagnostic techniques, specifically core needle biopsies performed under mammographic and ultrasonographic guidance. PMID- 9370072 TI - Surgery of breast cancer. AB - Near the beginning of this century, the aggressive surgical procedure of radical mastectomy to treat breast cancer was proposed by William S. Halsted. Today, the patient with newly diagnosed breast cancer and her surgeon have significantly more varied treatment options. Radical surgical resection has been supplanted by breast conservation therapy. Biopsy methods and the actual surgical techniques continue to be refined. Further developments have emerged in the debates over the efficacy of axillary dissection and sentinel lymph node biopsy. Diverse differences are seen in breast cancer of younger patients due to some fundamental distinctions in their disease. As we approach the next millenium it is clear that breast cancer is curable in a large percentage of women. While attention is turning to the investigation of the biologic and genetic factors involved with this disease, surgical regimens maintain a preeminent role in the overall quest for cure. PMID- 9370073 TI - Radiation therapy and breast cancer. AB - Although the role of radiation therapy in the management of ductal carcinoma in situ is somewhat controversial, the benefit of radiation therapy in breast conserving treatment of early stage invasive breast cancer is well established. Patients undergoing tumor excision with clear margins have low rates of recurrence with radiation therapy whether there is an extensive intraductal component or not. In all patients, there is a significantly higher risk of recurrence without radiation therapy. In patients receiving systemic therapy, the optimal sequence of chemotherapy and radiation therapy is still being defined; however, in patients with positive nodes and negative margins it is now clear that it is preferable to start chemotherapy first. PMID- 9370074 TI - Systemic therapy for breast cancer. AB - Currently available information suggests that the optimal duration of adjuvant therapy for breast cancer patients with no involved axillary nodes is 5 years, though controversy about this recommendation persists. In postmenopausal patients, disease-free survival appears to be improved by the addition of combination chemotherapy to tamoxifen. Recently reported studies indicate that there is no benefit to dose escalation of cyclophosphamide in adjuvant therapy and that the risk of secondary leukemia may be increased. The combination of paclitaxel and doxorubicin has been reported in single-institution studies to produce high response rates but may also be cardiotoxic. Recent reports indicate that a pharmacokinetic interaction between these two drugs may cause these clinical findings. New agents that may be of utility in the management of advanced or primary breast cancer include novel hormonal agents, notably the aromatase inhibitors, and the bisphosphonates. PMID- 9370075 TI - Inhibitors of multidrug resistance. AB - P-glycoprotein expression on tumor cells is a frequent cause of pleiotropic drug resistance in cell lines and tumor specimens. Besides the multidrug resistance gene (MDR1), other mechanisms of increased drug extrusion have been described, such as the MDR-related protein and the lung resistance protein. In addition, other gene-regulated processes may lead to cell survival after exposure to cytostatic agents. It has been shown that p-glycoprotein can be circumvented in vitro by noncytotoxic agents such as verapamil and cyclosporin A, which interact pharmacologically with p-glycoprotein-mediated efflux. More recently, molecular approaches to downregulate p-glycoprotein expression or function have been studied. These approaches and the clinical results obtained so far will be discussed. PMID- 9370076 TI - Cell adhesion and drug resistance in cancer. AB - The impact of cell adhesion in the pathobiology of tumors has been studied almost exclusively in the context of invasion, angiogenesis, and metastasis. Here we review data supporting a major role for cell-cell adhesion in the regulation of intrinsic or acquired resistance of solid tumors to various anticancer therapeutics. Cell-cell interactions are known to protect cells from apoptosis, and may help to explain chemoresistance of solid tumors. Recent data implicates p27KIP1, a cyclin-dependent kinase inhibitor, as a possible mediator of adhesion dependent drug resistance. A model is described whereby cell-cell interactions signal the upregulation of p27, which in turn causes growth arrest in the G1 phase of the cell cycle and resistance to apoptosis induced by anticancer agents that target rapidly dividing cells. We focus on E-cadherin, a homophilic cell cell adhesion molecule capable of upregulating p27, as one potential mediator of intrinsic resistance of carcinomas. A clearer understanding of how cell-cell adhesion suppresses cell growth and apoptosis should aid in the development of novel, more effective anticancer strategies. PMID- 9370077 TI - Inhibitors of prenyl transferases. AB - Because farnesylation of Ras is required for its cancer-causing activity, several classes of farnesyl transferase inhibitors have recently been developed as potential anticancer drugs. During the last 12 months, important advances have been made in this field. In this review, we focus on three topics: targets of farnesyl transferase inhibitors other than Ras, alternative prenylation of K-Ras by the closely related prenyl transferase, geranyl geranyl transferase I, and the effects of geranyl geranyl transferase I inhibitors on cell cycle, apoptosis, and human tumor growth. PMID- 9370079 TI - Toxicity antagonists in cancer therapy. AB - Modern cancer therapy produces substantial acute and chronic toxicity which impairs quality of life and limits the effectiveness of treatment. Recent clinical and laboratory data suggest that repair of treatment-related injury is a multiphase and continuous process providing multiple opportunities for pharmacologic intervention. A host of agents (toxicity antagonists) are under development that modulate normal tissue response or interfere with mechanisms of toxicity. Although significant challenges remain, the routine application of such agents promises to substantially reduce treatment related morbidity and potentially allow treatment intensification in high-risk disease. PMID- 9370080 TI - Adoptive immunotherapy. AB - Some of the most dramatic advances in the treatment of cancer have used the immune system in combination with conventional or transplantation chemotherapy. Adoptive immunotherapy has been used for relapses after allogeneic bone marrow transplantation, and it has been particularly effective for chronic myeloid leukemia. Adoptive immunotherapy also has been used for Epstein-Barr virus related lymphomas developing after allogeneic marrow transplantations. Cellular therapy, including the infusion of tumor-reactive immune cells, has been used to mediate response of established solid tumors. This has been used for therapeutic benefit for renal cell carcinoma, melanoma, lung cancer, and breast cancer. Current research is focusing on reducing the toxicity of these approaches as well as further defining the appropriate target tissue. PMID- 9370078 TI - Inhibitors of tyrosine kinase. AB - This review covers the literature on significant studies of small molecule inhibitors of the epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR), fibroblast growth factor receptor (FGFR), Flk-1, and src family tyrosine kinases from 1996 through mid-1997. During this period, there has been substantial progress in the discovery of new and highly specific tyrosine kinase inhibitors (TKIs), particularly for the EGFR family. The last 18 months saw a focused effort to discover tyrosine kinase inhibitors with increased potency, increased selectivity, better animal pharmacokinetics, and decreased toxicity. Indeed, some EGFR TKIs are now in clinical trials or are about to enter clinical trials as potential anticancer agents. Potent and selective kinase inhibitors have also been described for PDGFR, but none of these compounds have appeared to advance in the developmental process as far as kinase inhibitors for the EGFR family. Surprisingly, potent and selective inhibitors of receptors involved in neovascularization such as FGFR, Flk-1, or Flt-1 are less prevalent in the literature, and the discovery of TKIs that can inhibit angiogenesis remains a fertile area for drug discovery. Tyrosine kinases continue to remain an extremely attractive target for the design of potent and selective inhibitors that will represent an important new class of therapeutic agents for the treatment of a variety of diseases where current therapy is still insufficient. PMID- 9370081 TI - Clinical trials of antiangiogenic agents. AB - Acquisition of new blood vessels is a required step in malignant transformation, tumor growth, and metastasis. Inhibition of angiogenesis is one of the most promising new strategies for the treatment of malignant neoplasms. In recent years, several antiangiogenic compounds, including TNP-470, matrix metalloproteinase inhibitors, carboxyamidotriazole, and tecogalan sodium, have entered clinical trials. In this we review, we look at the results of early clinical trials of these agents and discuss the new angiogenesis inhibitors in preclinical development. PMID- 9370082 TI - Breast. PMID- 9370083 TI - Therapeutic modalities. PMID- 9370084 TI - Amygdala-hippocampal atrophy and memory performance in dementia of Alzheimer type. AB - The aim of the present study was to examine the involvement of brain structures, especially the amygdala-hippocampal complex, in dementia of Alzheimer type (DAT), and to assess the relation of amygdala-hippocampal atrophy with memory dysfunction. 14 patients with DAT and 10 healthy age-matched controls were examined with different neuropsychologic tests including the UCLA-Auditory Verbal Learning Test. MRI was performed with a conventional 1.5-tesla scanner. Atrophy was found in many brain structures of demented subjects in comparison with healthy age-matched controls. The volumes of amygdala-hippocampal complexes and of the temporal lobes of demented subjects were more reduced than the total brain volume and other structures. Memory dysfunction was highly correlated with atrophy of the amygdala-hippocampal complexes and of the temporal lobes. Consequently, DAT seems to affect the amygdala-hippocampal complex and their related function (i.e. memory) more than other cerebral structures, but cerebral degeneration in DAT is not restricted to these structures. PMID- 9370085 TI - Monomeric and polymeric forms of alpha-1 antichymotrypsin in sera from patients with probable late onset Alzheimer's disease. AB - Patients with probable late-onset Alzheimer's disease (l-AD) had higher levels of serum alpha 1-antichymotrypsin (alpha 1-ACT) than those found in patients with vascular dementia (VD) and healthy elderly controls, when assessed by a competitive enzyme-linked immune assay. Serum alpha 1-ACT was also characterized by SDS PAGE electrophoresis. Western blot and computer-assisted optical density reading (OD). Using a polyclonal affinity-purified antibody specific for human alpha 1-ACT, one band with the apparent MW of 60 and another with 180 kD in sera from all subjects were clearly detectable. OD of both alpha 1-ACT bands from patients with l-AD was higher than that from VD patients, the 180-kD form being 2.65 times higher than that observed from patients with VD. Serum levels of other acute phase proteins from l-AD were comparable to those observed in VD patients. A slight but nonstatistical increment of serum IL-6 was noted in patients with l AD. Serum alpha 1-ACT was purified from 3 of these l-AD patients by a two-step affinity chromatography technique. After Western blot, purified alpha 1-ACT showed two or three different bands which immune-reacted with an antibody specific for alpha 1-ACT. The apparent MWs were 60, 120 and 180 kD. In human sera the serpin was present mainly in a monomeric form, but it could also form SDS stable dimers and trimers. Both monomeric and SDS stable polymeric forms of alpha 1-ACT appeared to be increased in sera from patients with l-AD. PMID- 9370086 TI - Global dimensional complexity of multichannel EEG in mild Alzheimer's disease and age-matched cohorts. AB - Multichannel EEG as sequence of momentary brain field maps constitutes a trajectory through K-dimensional state space (K = number of channels); the complexity of this trajectory is assessed by the nonlinear measure of global correlation dimension (Global Dimensional Complexity, GDC) with the number of electrodes as embedding dimension. We analyzed eyes-closed EEG of three age matched subject groups: mild Alzheimer's disease (AD; n = 21), mild cognitive impairment (29) and subjective memory complaint (29). Kruskal-Wallis statistics showed an overall effect between groups. AD patients differed significantly (GDC = 4.56) from mild cognitive impairments (GDC = 4.98) and from subjective memory complaints (GDC = 4.93). GDC also had significant positive correlations with mental condition and performance (MMSE and WAIS-R scores). Thus, the dynamics of brain state development over time in mild AD differs from that in mild cognitive impairment and in subjective memory complaint cases. PMID- 9370087 TI - A SPECT imaging study of MRI white matter hyperintensity in patients with degenerative dementia. AB - We investigated the correlation between cortical perfusion and white matter hyperintensities on magnetic resonance images (MRI) of patients with dementia. The study included 40 subjects, each of whom had undergone both MRI and single photon emission computed tomography (SPECT) studies as part of their diagnostic evaluation for degenerative dementia. Two neuroradiologists rated the MRI films for severity of periventricular white matter changes on a 0-5 point scale and severity of subcortical white matter changes on a 0-4 point scale. Twelve regions of interest from association cortex were sampled for the semiquantitative analysis of SPECT images. No relationship was found between these global MRI ratings and semiquantitative or qualitative SPECT findings. Dementia severity as measured by the Mini-Mental State Examination and the Clinical Dementia Rating was significantly correlated with SPECT, whereas age was significantly correlated with MRI ratings, particularly in the periventricular regions. These data support the view that cortical SPECT abnormalities are not associated with global MRI abnormalities in the subcortical and periventricular regions of patients with a clinical picture of degenerative dementia. PMID- 9370088 TI - Early-stage Alzheimer's disease and multiple subcortical infarction with mild cognitive impairment: neuropsychological comparison using an easily applicable test battery. AB - We conducted a neuropsychological study comparing early-stage Alzheimer's disease (AD; n = 22) and multiple subcortical infarction with mild cognitive impairment (MSI; n = 22) using an easily applicable test battery which included 8 tests. Two groups were matched for age, education and score on the Mini-Mental State Examination. Patients with AD had significantly lower scores than MSI patients in the delayed recall of the Rey-Osterrieth Complex Figure, while MSI patients had significantly worse scores in the Wisconsin Card-Sorting Test. This suggests that early discrimination of MSI from AD can be made by frontal system impairment in MSI and episodic memory disturbance in the visuospatial domain in AD using simple neuropsychological tests. PMID- 9370089 TI - Assessment of ambulatory behavior in nursing home residents who pace or wander: a comparison of four commercially available devices. AB - This study evaluated four devices--a Pedometer, Step Sensor, Actigraph, and Personal Activity Meter (PAM)--as measures of pacing behavior. Ten nursing home residents who frequently paced in a long-term care facility underwent 1 day of data collection with each of the devices. Data derived from devices were compared to behavioral observations regarding the number of steps taken. Additionally, devices were evaluated via ratings concerning ease of use, and how well residents tolerated them. All devices yielded high correlations with the observed number of steps, with highest correlations for the PAM and Actigraph. All devices were tolerated well. The Pedometer and Step Sensor were the easiest to use. This study demonstrated that these devices offer an objective means to measure pacing/wandering behavior. PMID- 9370090 TI - Comparative effects of ageing and dementia of the Alzheimer type on orientation of visual attention. AB - Age-related changes and the effects of dementia of the Alzheimer type (DAT) were investigated during a visual orienting attention task in which attention was pre cued to one or other hemifields. Central cues were either valid, neutral, invalid or NoGo (inhibitory). The response time cost-benefit analysis showed a decreased benefit after valid cueing in the old compared with the young group with no change in the cost of invalid cueing. The older group were also slower over all cue types. These results suggest there is an age-related reduced ability to covertly orient attention in a visual hemifield before target onset. In contrast, the DAT group showed an increased response time benefit and showed a trend for a decreased cost in response time compared with controls. This was due to slowest response times after neutral cues. They also made significantly more response errors particularly following neutral cueing, and were less able to inhibit responses on NoGo trials than controls. The increased benefit and reduced cost found in the DAT group was interpreted as an impairment in dividing attention between left and right target locations. PMID- 9370092 TI - Borrelia burgdorferi-seropositive chronic encephalomyelopathy: Lyme neuroborreliosis? An autopsied report. AB - A 36-year-old Japanese woman presented with progressive cerebellar signs and mental deterioration of subacute course after her return from the USA. Her serum antibody to spirochete Borrelia burgdorferi was significantly elevated. A necropsy 4 years after her initial neurological signs revealed multifocal inflammatory change in the cerebral cortex, thalamus, superior colliculus, dentate nucleus, inferior olivary nucleus and spinal cord. The lesions showed spongiform change, neuronal cell loss, astrocytosis and proliferation of activated microglial cells. The internal capsule was partially vacuolated and the spinal cord, notably at the thoracic level, was demyelinated and cavitated in the lateral funiculus. Microglial cells aggregated within and around the spongiform lesions and microglial nodules were present in the medulla oblongata. Use of Warthin-Starry stain demonstrated silver-impregnated organisms strongly suggesting B. burgdorferi in the central nervous tissues. The dentate nucleus and inferior olivary nucleus showed the most advanced lesions with profound fibrillary gliosis. Occlusive vascular change was relatively mild, and fibrous thickening of the leptomeninges with lymphocyte infiltrates was localized in the basal midbrain. The ataxic symptoms were due to the dentate and olivary nucleus lesions and mental deterioration was attributable to the cortical and thalamic lesions. Spongiform change, neuronal cell loss, and microglial activation are characteristic pathological features in the present case. The cerebellar ataxia and subsequent mental deterioration are unusual clinical features of Lyme neuroborreliosis. Spirochete B. burgdorferi can cause focal inflammatory parenchymal change in the central nervous tissues and the present case may be an encephalitic form of Lyme neuroborreliosis. PMID- 9370091 TI - Episodic memory functioning in population-based samples of very old adults with Alzheimer's disease and vascular dementia. AB - Population-based samples of normal old adults, patients with Alzheimer's disease (AD), and patients with vascular dementia (VaD) between 90 and 100 years of age were given a series of episodic memory tasks, assessing face recognition, word recall, and object recall. Results indicated (a) no group differences in those variables reflecting primary memory, and clear dementia-related deficits in secondary memory; (b) no differences between persons with AD and VaD in face recognition and object recall, and (c) an advantage of VaD patients compared with AD patients in word recall. It was suggested that the ability to transfer information from temporary to permanent storage may be particularly affected by a dementing disease. In addition, the selective AD-related deficit in word recall was interpreted in terms of a greater impairment of various language-related skills in AD compared with VaD. PMID- 9370093 TI - Consensus statement on lung cancer. Lung Cancer Panel. PMID- 9370094 TI - Programmed cell death: will it become a factor in cancer prevention? AB - Among the factors triggering programmed cell death (PCD) are a number of known carcinogens, and several consequences of DNA abnormalities characteristic of cancer have been shown capable of eliciting the PCD response. So although elimination of a potentially malignant cell is likely to be a rare consequence of PCD it could turn out to be important for cancer development. A brief survey is given of the most well-known triggering factors, the molecular mechanisms of the pathways involved and the emerging experimental and clinical data relating capacity of PCD to cancer initiation and progression. It is suggested that future cancer prevention will have to consider also those factors which may abrogate normal PCD. PMID- 9370095 TI - Reduced testosterone, 17 beta-oestradiol and sexual hormone binding globulin, and increased insulin-like growth factor-1 concentrations, in healthy nulligravid women aged 19-25 years who were first and/or second degree relatives to breast cancer patients. AB - Differences in hormonal and constitutional parameters between women with at least one first and/or second degree relative with breast cancer (RBC) and women without such affected relatives were studied in a group of healthy, nulligravid women aged 19-25 years. Present oral contraceptive (OC) users were analysed separately. In women not presently exposed to OCs we found significant correlations between RBC and reduced concentrations of testosterone during both the follicular (P < 0.001) and luteal menstrual cycle phases (P = 0.016). 17 beta oestradiol was also significantly negatively correlated with RBC in the follicular (P = 0.044) and in the luteal phase (P = 0.027). RBC was significantly correlated with a lower waist/hip ratio (P = 0.044) compared with women without such a history. In multivariate analyses, the results for testosterone but not 17 beta-oestradiol remained significant. In these analyses high IGF-1 (P = 0.05) in the follicular phase and low sexual hormone-binding globulin (SHBG) (P = 0.04) in the luteal phase were also related to RBC. Including all 66 women in a multivariate model that analysed the specific effects from OCs and RBC on plasma testosterone showed that plasma testosterone was significantly lower among present OC users (P = 0.004) and in women with RBC (P = 0.005) during cycle days 5-10, with a significant positive two-way interaction between present OC use and RBC (P = 0.007). During cycle days 18-23 plasma testosterone showed a significant negative relationship with present OC use (P < 0.001) and RBC (P = 0.016) no significant interaction was seen during cycle days 18-23. Factors not significantly related to RBC were height, weight, breast size, age at menarche, p progesterone and p-prolactin. It is concluded that a family history of breast cancer significantly lowered plasma testosterone concentrations in both cycle phases among healthy, nulligravid women compared with women without such history. PMID- 9370096 TI - Explaining breast cancer mortality in England: the effect of socioeconomic factors and health care services. AB - England has the worst mortality rate for breast cancer in the developed world. Using area-level data for 145 health districts in England, this study seeks to explain variations in breast cancer mortality among women aged 50-64 years in the period before the National Breast Screening Programme became operational. It is found that socioeconomic and behavioural factors had a larger effect on mortality than did health care inputs. This might be explained both by inadequacies in the data, and by the fact that, in the absence of screening, cancers tend to be detected at a later stage, by which time the chances of a successful outcome are reduced. It is suggested that the impact of health care services in reducing mortality will increase in the future as screening becomes widespread and results in earlier detection and treatment. The prioritization of screening is central to achieving the reductions in mortality from breast cancer specified in the Health of the Nation targets. PMID- 9370097 TI - Salivary nitrate, nitrite and N-nitroso compounds in patients with cancer of the upper aerodigestive tract. AB - N-nitroso compounds are carcinogens that can be ingested directly or synthesized from nitrites and nitrates. The possible role of N-nitroso compounds in the induction of upper aerodigestive tract tumours was considered in a case-control study conducted in the Valle d'Aosta, an Italian region with a high incidence of these neoplasms. Nitrate, nitrite, labile and stable N-nitroso compounds were analysed in the saliva of 36 patients with cancers of the upper aerodigestive tract and 23 healthy individuals. After allowing for tobacco, salivary nitrate, nitrite and N-nitroso compounds were not associated with an increased risk of upper aerodigestive tract cancers. The odds ratio for continuous units of total N nitros compounds was 0.99 (95% confidence interval 0.9-1.1). Thus, salivary nitrate, nitrite and N-nitroso compounds might not be suitable markers for the assessment of the risk of cancer of the upper aerodigestive tract, although a role for N-nitroso compounds cannot be excluded. PMID- 9370098 TI - Inhibition by acetaminophen of intestinal cancer in rats induced by an aromatic amine similar to food mutagens. AB - The widely used analgesic acetaminophen (APAP) was studied in rats for its ability to inhibit intestinal carcinogenesis induced by 3,2'-dimethyl-4 aminobiphenyl (DMAB), which was selected as the carcinogen because of its similarity to the heterocyclic amines formed during cooking and which are postulated to be involved in colon cancer in humans. APAP was fed to male F344 rats at 250 ppm, which is about 1/4 the human therapeutic dose and at 5000 ppm, which is about fivefold the human dose. DMAB was injected subcutaneously at 50 mg/kg body weight weekly for 20 weeks, to assure identical exposures to all animals, followed by 22 weeks of maintenance. The DMAB was an effective inducer of tumours in the small and large intestines, producing an average of 1.3 tumours per animal. Feeding of APAP began 2 weeks before DMAB administration and continued for 44 weeks. A 9% reduction in the number of colon tumours per rat cancer at the low dose and an 86% reduction at the high dose were found. Small intestinal tumour incidence was reduced at both doses. The number of multiple intestinal tumours per rat was reduced by 27% and 49% for the low and high doses, respectively. The dimensions of these neoplasms, especially those in the colon, were also reduced in both dose groups. Thus, APAP, even at a sub-therapeutic dose, inhibited intestinal carcinogenesis induced by DMAB. This allows us to speculate that the effects of low exposures to dietary carcinogens of the heterocyclic amine type could be inhibited by therapeutic doses of APAP. PMID- 9370099 TI - Risk factors for bladder cancer: a case-control study in northeast China. AB - A case-control study of risk factors for bladder cancer was carried out in Heilongjing Province, China. Between May 1989 and May 1990, 217 histologically confirmed cases of bladder cancer and 254 controls with non-neoplastic and non urine system disease were recruited. Individuals were interviewed in the wards of six major hospitals. Controls were matched by sex, age and area of residence. Information was collected concerning economic status, occupation, histories of smoking and consumption of alcohol, use of tea, the taking of analgesics, dietary histories and previous diseases. Odds ratios (ORs) were calculated from stratified analysis and conditional logistic regression models. Increased risk was observed with increasing times per year and number of years of saccharine use. Compared with non-users, the use of saccharine for more than 19 times per year, and for more than 15 years, the adjusted ORs were 3.9 (95% CI = 1.8-8.67) and 5.1 (95% CI = 2.3-11.6), respectively. Statistically significant associations were also found for diseases related to the urinary system (OR = 2.8; 95% CI = 1.1-7.6). Increased consumption of fruit and vegetable may reduce the risk of bladder cancer. Cigarette smoking had no effect on the risk of bladder cancer in both genders. There was no association between the consumption of alcohol or tea, or types of water supply, with bladder cancer risk. PMID- 9370101 TI - Relation between fat intake and mortality: an ecological analysis in Belgium. AB - A representative sample of the Belgian population, aged 25-74 years, was interviewed between 1980 and 1985. Dietary habits were assessed using a 24 h food record method. Age-, sex- and district-specific energy-adjusted averages of macronutrient intakes were compared with mortality rates from 1988-90, with special emphasis on the association between fat intake and cancer mortality. Univariate analyses were followed by multiple linear regression analyses, controlling for possible confounders such as fibre intake, smoking and educational level. In multivariate analyses, significant positive associations were found between all-causes mortality and saturated fat intake in men, and between all-causes mortality and the ratio of n-3 to n-6 fatty acids in men; colorectal cancer mortality was associated with polyunsaturated fat intake and with the ratio of unsaturated to saturated fat in men. Significant negative associations were found between all-causes mortality and polyunsaturated fat intake in men, and between all-causes mortality and the ratio of unsaturated to saturated fat in men; colorectal cancer mortality was associated with saturated fat intake in men. In women, only breast cancer mortality was associated with saturated and monounsaturated fat intake. Prostate cancer mortality was not related to any of the studied dietary fat components. For total cancer mortality, only weak non-significant associations with fat intake were found. PMID- 9370100 TI - Fats in seasoning and the relationship to pancreatic cancer. AB - The relationship between consumption of fat in seasoning and the risk of pancreatic cancer has been considered in a case-control study conducted in Italy between 1983 and 1995 on 362 pancreatic cancer cases and 1502 controls in hospital for acute, not neoplastic, non-digestive tract disorders. Subjective scores (low, intermediate, high) for the intake of butter, margarine and oil were used to evaluate the use of fat in seasoning. No material association was observed for butter or margarine. The score for oil (mainly olive oil) intake was inversely related to the risk of pancreatic cancer: the multivariate odds ratios were 0.76 for the intermediate, and 0.60 for the highest score of intake, and the trend in risk was significant. These findings support the hypothesis that (olive) oil may have a comparatively more favourable impact on the risk of pancreatic cancer than other types of seasoning fats. PMID- 9370102 TI - Cigarette smoking and risk of prostate cancer: a population-based case-control study in Ontario and British Columbia, Canada. AB - The relationship between cigarette smoking and risk of prostate cancer was examined in a case-control study conducted in Ontario and British Columbia, Canada. In each centre, cases were men with a histologically confirmed diagnosis of adenocarcinoma of the prostate notified to the provincial cancer registry. In Ontario, controls were selected randomly from assessment lists maintained by the Ontario Ministry of Revenue and were frequency matched to the cases on age. In British Columbia, controls were also frequency matched to the cases on age and were selected randomly from a roster maintained by the Medical Services Plan of British Columbia. The study in Ontario was conducted between April 1990 and April 1992, and that in British Columbia was conducted between January 1989 and December 1991. In all, the study included 408 cases (207 in Ontario and 201 in British Columbia) and 407 controls (207 in Toronto and 200 in British Columbia (one case was unmatched). Overall, there was little variation in risk of prostate cancer with pack-years of cigarette consumption (filter and non-filter cigarettes combined), and there was no evidence for an effect confined to filter or non filter cigarettes. There was some evidence for a positive association with non filter cigarettes in British Columbia, but on formal testing for heterogeneity, this finding was not inconsistent with the absence of an association in Ontario. There was also little variation in risk by years since first smoked or (for ex smokers) by years since quitting. These data provide little support for an association between cigarette smoking and prostate cancer risk. PMID- 9370103 TI - Cervical cancer screening in the Flemish region (Belgium): measurement of the attendance rate by telephone interview. AB - In November and December 1995 a computer assisted telephone interview (CATI) was organized in order to measure the rate of participation in cervical cancer screening among a sample of 1,477 women between 18 and 69 years old, residing in the Flemish Region and selected by random digit dialling. Associations between screening status and a set of explanatory variables (demographic, socioeconomic determinants and exposition to primary risk factors for cervical cancer) were studied by logistic regression modelling. The screening coverage meaning the percentage of women screened less than 3 years ago, increases sharply up to 25 years and remains higher than 85% up to 40 years; from then it decreases progressively. Socioeconomically deprived groups and single women are less likely to have a smear taken. Notable regional differences exist. Over-screening (interval between Papanicolaou smears less than 3 years) is an important phenomenon among screened women especially within the younger age groups. The prevalence of risk factors (sexual intercourse at young age, multiple sex partners, contraceptive pill use, smoking) has increased over time but women at higher risk are generally better screened. This survey provides useful baseline information necessary to monitor the achievement of some main objectives, formulated by the Europe Against Cancer programme and also included in Flemish public health policy. PMID- 9370104 TI - Chemopreventive effects of sandalwood oil on skin papillomas in mice. AB - The essential oil, emulsion or paste of sandalwood (Santalum album L) has been used in India as an ayurvedic medicinal agent for the treatment of inflammatory and eruptive skin diseases. In this investigation, the chemopreventive effects of sandalwood oil (5% in acetone, w/v) on 7,12-dimethylbenz(a)anthracene-(DMBA) initiated and 12-O-tetradecanoyl phorbol-13-acetate(TPA)-promoted skin papillomas, and TPA-induced ornithine decarboxylase (ODC) activity in CD1 mice were studied. Sandalwood oil treatment significantly decreased papilloma incidence by 67%, multiplicity by 96%, and TPA-induced ODC activity by 70%. This oil could be an effective chemopreventive agent against skin cancer. PMID- 9370105 TI - Consensus statement on diet and gastric cancer. Gastric Cancer Panel. PMID- 9370106 TI - Glucagon-like peptide 1 and its potential in the treatment of non-insulin dependent diabetes mellitus. AB - Studies examining small groups of type 2-(NIDDM) diabetic patients have shown the potential of glucagon-like peptide 1 (GLP-1) to normalize fasting hyperglycaemia. Patient characteristics determining the size of the effect have not been reported. Therefore, the results of four studies were analysed. Exogenous GLP-1 was administered i.v. or s.c. in 37 type 2-diabetic patients, age 60 +/- 8 years; BMI 28.2 +/- 5.3 kg/m2; HbA1c 10.6 +/- 1.6%; diabetes duration 10 +/- 6 years, treatment with sulfonylureas, n = 33, metformin, n = 11, acarbose, n = 3. Results were analysed using repeated measures analysis of variance and multiple regression analysis. Exogenous GLP-1 lowered fasting plasma glucose within 4-5 h from 12.8 +/- 2.5 to 5.3 +/- 1.3 mmol/l (placebo: 12.8 +/- 2.3 to 10.0 +/- 2.2; p < 0.0001 for the interaction of treatment and time). Only fasting glycaemia (p = 0.0085) and the route (i.v. vs. s.c.; p = 0.05), but not gender, age, BMI, HbA1c, diabetes duration, treatment with sulfonylureas, metformin or acarbose, were significant predictors of the plasma glucose concentrations reached after the administration of GLP-1 (variation: 3.4-8.5 mmol/l). In conclusion, GLP-1 is able to normalize plasma glucose in all type 2-diabetic patients studied. This analysis underlines the great therapeutic potential of GLP-1. PMID- 9370107 TI - GLP-1 (7-36) amide: effects on glucose transport and metabolism in rat adipose tissue. AB - In rat adipocytes, GLP-1 (7-36) amide induced an increment in 2-deoxy-glucose uptake, which was additive to that of insulin. Furthermore, in rat fat, GLP-1 (7 36) amide provoked a rise in glycogen synthesis, glucose oxidation and utilization and lipogenesis, the increments being lower than those obtained with insulin. These data support the idea that GLP-1 exerts insulin-like effects on glucose metabolism in rat adipose tissue, as it does in rat hepatocytes and skeletal muscle, although with a lower potency than that of insulin. PMID- 9370108 TI - Secretory profile of immunoreactive growth hormone-releasing hormone (IR-GHRH) during sleep in man and its clinical value. AB - To clarify the role of growth hormone-releasing hormone (GHRH) in the regulation of the episodic growth hormone (GH) secretion which is known to occur constantly in the initial slow wave stage of nocturnal sleep in man, we studied the relation between the secretions of plasma immunoreactive(IR)-GHRH and GH while recording electroencephalograms. In subjects who showed a normal sleep pattern, the plasma IR-GHRH level increased 3- to 4-fold just before the surge of plasma GH, suggesting that GH release in the initial slow wave stage of sleep is mainly mediated by GHRH. However, when there was an apparent GH surge just before the onset of sleep, the magnitude of the GH response associated with the initial slow wave stage tended to be blunted, even when sufficient IR-GHRH was released. We also observed no appreciable fluctuations of plasma IR-GHRH during nocturnal sleep in a patient diagnosed as having GH-deficient dwarfism, suggesting the primary lesion was on the hypothalamus level, not the pituitary, in such a patient. In a case of multiple endocrine neoplasia (MEN) type I with an ectopic (GHRH-producing pancreatic tumor, no remarkable elevation of plasma IR-GHRH was detected in the initial slow wave stage of nocturnal sleep. We conclude that the present study is significant not only in demonstrating the physiology of GHRH release, but also in establishing a safe, reliable and practical test for routine clinical use to investigate intrinsic ability to release GHRH and the primary lesions in patients with disorders of GH secretion. PMID- 9370109 TI - Effects of gamma-butyric acid on the release of thyrotropin-releasing hormone from the rat retina in vitro. AB - Effects of gamma-butyric acid (GABA) on the release of thyrotropin-releasing hormone (TRH) from the rat retina in vitro were studied. The rat retina was incubated in medium 199 (pH 7.4) with 1.0 mg/ml of bacitracin and 100 micrograms/ml of ascorbic acid (medium). The amount of TRH release into the medium was measured by radioimmunoassay. The TRH release from the rat retina was inhibited significantly in a dose-related manner with the addition of GABA, but not with bicuculline. The inhibitory effect of GABA on TRH release from the retina was blocked by adding bicuculline to the medium. The findings suggest that the GABAergic system inhibits TRH release from the rat retina in vitro. PMID- 9370111 TI - Effects of the carnitine-acyltransferase inhibitor etomoxir on insulin sensitivity, energy expenditure and substrate oxidation in NIDDM. AB - We studied the influence of Etomoxir on fat and carbohydrate oxidation, and the influence of these changes on insulin sensitivity in type 2 diabetic patients. Etomoxir is an oxirane carboxylic acid derivative that specifically inactivates carnitine-acyltransferase I (CAT I, EC: 2.3.1.21), the key enzyme for the transport of long-chain acyl-CoA compounds into the mitochondria. Thus, oxidation of fatty acids should be reduced by this drug and glucose utilisation be increased according to the Randle mechanism. In order to test this hypothesis, we measured oxidative and non-oxidative glucose utilisation using the euglycaemic hyperinsulinaemic clamp technique, the isotope dilution mass spectrometry (IDMS) method with stable isotopes (6,6-D2-glucose) and indirect calorimetry. The clamps lasted 5 hours, indirect calorimetry was performed during the last hour and calculations of glucose disposal were based on steady state conditions during the last 30 minutes. Twelve type 2 diabetic patients were treated with 100 mg etomoxir/per day for 3 days in this placebo-controlled, randomized, double-blind study. Treatment resulted in a significant increase in carbohydrate oxidation (from 72 to 113 g/24 h, p = 0.039), decrease in fat oxidation (from 139 to 114 g/24 h, p = 0.037), and decrease of the glucose appearance rate (RA) in the basal state (from 1.85 to 1.70 mg/kg min., p = 0.014). During the euglycaemic clamp neither RA (3.30 and 3.20 mg/kg min., p = 0.471) nor the glucose infusion rate (4.28 and 4.53 mg/kg min., p = 0.125) showed significant changes. In addition, no significant changes in glucose and fat oxidation were detected during the hyperinsulinaemic clamp. Under basal conditions non-oxidative glucose utilisation was decreased by etomoxir (1.26 and 0.80 mg/ kg x min). Thus, we could demonstrate a decrease in fat and increase in glucose oxidation by etomoxir, but non-oxidative glucose utilisation was decreased. No significant changes could be demonstrated under clamp conditions. PMID- 9370110 TI - Reduced effects of L-carnitine on glucose and fatty acid metabolism in myocytes isolated from diabetic rats. AB - Depressed glucose utilization and over-reliance of muscle tissues on fat represents a major metabolic disturbance in diabetes. This study was designed to investigate the relationship between fatty acid oxidation and glucose utilization in diabetic hearts and to examine the role of L-Carnitine on the utilization of these substrates in diabetes. 14CO2 release from [1-14C]pyruvate (an index of PDH activity), [2-14C]pyruvate and [6-14C]glucose (an index of acetyl-CoA flux through the Krebs cycle), [U-14C]glucose (an index of both PDH and acetyl-CoA flux through the Krebs cycle), and [1-14C]palmitate oxidation were studied in cardiac myocystes isolated from normal and streptozotocin-injected rats. Palmitate oxidation was increased twofold in diabetic myocytes compared to normal cells (5.4 +/- 1.45 vs 2.35 +/- 0.055 nmol/mg protein/30 min, p > 0.05). L Carnitine (5 mM) significantly increased palmitate oxidation (60-70%) in normal cells but had no effect on diabetic cells. The activity of PDH and acetyl-CoA flux through the Krebs cycle was severely depressed in diabetes (58.14 +/- 20.27 and 8.63 +/- 0.62 in diabetes vs 128.75 +/- 11.47 and 24.84 +/- 7.81 nmol/mg protein/30 min in controls, p > 0.05, respectively). The efflux of acetylcarnitine, a by-product of PDH activity was also much lower in diabetic cells than in normal cells but had no effect in diabetes. L-Carnitine also had no effect on 14CO2 release from [U-14C]glucose but significantly decreased that from [6-14C]glucose, which reflects oxidative metabolism suggesting that L-Carnitine decreases oxidative glucose utilization. Thus, these data suggest that the overreliance on fat in diabetes may be in part secondary to a reduction of carbohydrate-generated acetyl-CoA through the Krebs cycle. PMID- 9370112 TI - Detection of hypoglycaemia by microdialysis measurements of glucose in subcutaneous adipose tissue. AB - The aim of the present investigation was to study how various fractional sampling times affect the detection of hypoglycaemia, using microdialysis of the adipose tissue. We therefore studied eight healthy subjects during a standardized hyperinsulinaemic hypoglycaemic clamp. The glucose concentration in the adipose tissue dialysate was determined in timed fractions of 15 min, 30 min and 60 min and compared to those in arterialized venous plasma. Before and after hypoglycaemia, the plasma and adipose tissue glucose concentrations were similar. However, during hypoglycaemia, the adipose tissue glucose nadir, as measured in 15-min fractions of the tissue dialysate, was significantly lower than that in plasma (2.1 +/- 0.1 vs. 2.4 +/- 0.1 mmol/l, p = 0.05) and during the increase in plasma glucose, the corresponding increase in adipose tissue glucose was delayed by approximately 20 min (p = 0.004). When the microdialysate was sampled over 30 or 60 min periods, there was a close agreement between the plasma and adipose tissue glucose nadirs. We conclude that there is a protracted fall in subcutaneous adipose tissue glucose levels in response to insulin-induced hypoglycaemia. While shorter microdialysis sampling periods improve the resolution of the hypoglycaemic event, 30-min fractions seem sufficient to detect hypoglycaemia in a clinically relevant way. PMID- 9370113 TI - Pioglitazone reduces smooth muscle cell density of rat carotid arterial intima induced by balloon catheterization. AB - The effect of pioglitazone on balloon catheterization-induced carotid arterial intimal thickening lesion of male Wistar fatty rats and its littermates (Wistar lean rats) was investigated. Pioglitazone was administered via gastric tube at 10 mg/kg/day to 12-week-old rats for 7 days. Age-matched rats without pioglitazone were used as respective controls. Each rat was catheterized using a balloon catheter inserted from the left femoral artery to the left common carotid artery, and the endothelium in the left common carotid artery was denuded. Rats were then treated with pioglitazone for 14 days post catheterization and the left common carotid artery was removed and stained with Elastica-Masson and anti-alpha-smooth muscle actin antibody. In addition, for smooth muscle cell (SMC) culture, pioglitazone was administered at 10 mg/kg/day for 28 days to a separate group of 12-week-old rats, and the aortic medial outgrowth rate of their SMCs was measured. Age-matched rats without pioglitazone were prepared as respective controls. In comparison with the area ratio of the thickened intima/media of fatty rats without treatment, those of fatty rats with treatment and lean rats without treatment were significantly decreased by approximately 60%, and also that of lean rats with treatment to 27%. With anti-alpha-smooth muscle actin antibody staining, almost all cells present in intimal thickening were positive. Treatment with pioglitazone reduced the amount of anti-alpha-smooth muscle actin antibody-staining cells. In addition, the outgrowth rate of SMCs at day 10 compared to that in fatty rats without treatment decreased to 42% in fatty rats with treatment, 29% in lean rats without treatment and 23% in lean rats with treatment, respectively. Therefore, pioglitazone has an inhibitory effect on the growth of SMCs, and consequently suppressed carotid intimal thickening. Furthermore, this inhibitory effect was enhanced in diabetes. PMID- 9370114 TI - Diet and day-to-day variability in a sample of Spanish adults with IDDM or NIDDM. The Diabetes and Nutrition Study Group of the Spanish Diabetes Association (GSEDNu). AB - OBJECTIVE: To ascertain the nutritional pattern, including the day-to-day variability in the macronutrients consumption, in Spanish adults with IDDM or NIDDM. RESEARCH DESIGN AND METHODS: The diabetes Nutrition and Complications Trial (DNCT) is a prospective multicentre study designed for finding out which is the nutritional behaviour of diabetic subjects in Spain, based on a diet record that patients prospectively fill in for 7 days. Day-to-day variability in nutrients intake is given as the mean of the mean standard deviations of the daily macronutrients intake, as well as the mean of the mean coefficients of variation. Glycaemic control was assessed by measuring the HbA1c during the study period and the mean of the 3 previous determinations. Data of the first 60 patients (30 IDDM, M/F 15/15, 30 NIDDM, M/F 15/15) are shown in this paper. RESULTS: The overall energy intake of Spanish subjects with IDDM or NIDDM, expressed as median, are 1978 and 1707 Kcal/ day, respectively, were distributed as follows (IDDM and NIDDM): Carbohydrate 36.5 and 37.4%, protein 17.9 and 20.0%, fat 41.7 and 36.8% (saturated 14.7 and 11.6%, polyunsaturated 5.0 and 4.2%, monounsaturated 22.1 and 20.8%, saturated/total fat ratio 0.29 and 0.26, cholesterol 279 and 245 mg), alcohol 2.6 and 4.2%, dietary fibre 19 and 15 gr. Women received less energy than men and subjects with NIDDM ate less than subjects with IDDM (both p < 0.05). The means of the standard deviations of the average carbohydrate intake were 37.0 +/- 20.1 and 28.9 +/- 20.9 g., whereas the means of the coefficients of variation were 18.3 +/- 8.5 and 15.5%, expressed as the average percentage of carbohydrates intake for both IDDM and NIDDM subjects, respectively. There was no correlation between the day-to-day variability in carbohydrate intake and HbA1c. CONCLUSIONS: Diet of diabetic patients in Spain is low in carbohydrate and high in fat content, mainly monounsaturated fat. Day-to day variability in carbohydrate intake is not associated with the glycaemic control. PMID- 9370115 TI - The effects of streptozotocin-induced hypoinsulinemia on serum lipid levels in spontaneously hyperlipidemic rats. AB - We compared the effects of streptozotocin (STZ) treatment on serum cholesterol and lipoprotein levels in spontaneously hyperlipidemic rats (HLR), a hereditary hyperlipidemic model animal, with those in Sprague-Dawley rats (SDR). The body weight of control SDR and HLR were increased continuously for 30 days. Both SDR and HLR lost their body weight after STZ administration. Glucose levels of SDR and HLR were significantly increased by STZ treatment. Insulin levels were markedly decreased in HLR compared with those in SDR. Serum cholesterol and triglyceride levels of HLR treated with STZ were significantly higher than those of untreated HLR. The increment of both levels in HLR was much larger than that in SDR. The high density lipoprotein (HDL) cholesterol level of the STZ-treated HLR was significantly lower than that of untreated HLR. In the STZ-treated HLR the intensities of both bands of the very low density lipoprotein (VLDL) and the low density lipoprotein (LDL) were higher than those in untreated HLR, while the intensity of any lipoprotein band remained unchanged between STZ-treated and control SDR. The atherogenic index (the ratio of total cholesterol level minus HDL cholesterol level of HDL cholesterol level) in the STZ-treated HLR was significantly high compared with that in other groups. The STZ-treated HLR showed the extremely hyperlipidemic state and this animal might be useful in experiments for the development of atherosclerosis or the drug evaluation for the agents used in hyperlipidemia. PMID- 9370116 TI - The effects of high altitude trekking on body composition and resting metabolic rate. AB - Resting metabolic rate (RMR) and body composition were evaluated in 12 healthy volunteers before and after 16 days of high altitude trekking and climbing. RMR was measured by indirect calorimetry and body composition by electrical impedance. A 29% reduction in energy intake during high altitude exposure was observed. Fat mass loss averaged about 2.2 kg (p < 0.05) and lean body mass about 1.1 kg, which was almost significant (p = 0.07). As expected, estimated RMR at the end of the expedition--calculated by predictive formulae including body fat and lean body mass as covariates--was significantly reduced by 119 kcal/day as a consequence of the reduction in body weight. Measured RMR values, on the contrary, did not show any significant decline. In conclusion our study showed that high altitude trekking induced a weight loss due approximately 2/3rds to fat mass and 1/3rd to lean body mass. Decreased energy efficiency, which was still present several days after returning to sea level, may have helped contribute to weight loss due to reduced energy intake. PMID- 9370117 TI - Changes in LDH isozyme pattern in uterine fluid of mice during early pregnancy. AB - The total LDH activity in the uterine fluid of mice shows a rising trend from the first day after mating (DAM-1) to the seventh day after mating (DAM-7). This suggests that LDH activity increases as gestation progresses. During early pregnancy, M-isozymes of LDH show a predominance from DAM-1 to DAM-3 in the uterine luminal fluid of mice, while H-isozyme shows a rising level from DAM-5 (implantation day) and attains a maximum level at DAM-7 (the post-implantation period). Such shift of M-isozymes into H-isozymes of LDH (lactate dehydrogenase) during pre-implantation (DAM-3) to post-implantation (DAM-7) period changes the uterine luminal environment from anaerobic to aerobic condition which is more conducive for the normal development, implantation and survival of the growing blastocyst. PMID- 9370118 TI - Inhibition of rat renal and testicular 11 beta-hydroxysteroid dehydrogenase by some antihypertensive drugs, diuretics, and epitestosterone. AB - With regard to previous finding of an inhibitory activity of furosemide on 11 beta-hydroxysteroid dehydrogenase, 16 other commonly used diuretics have been tested as to their ability to inhibit rat renal, and in four instances also testicular 11 beta-hydroxysteroid dehydrogenase, using glycerrhetinic acid as a standard. In addition, epitestosterone has been tested as well, with respect to its recently demonstrated inhibitory activity on several other enzymes of androgen biosynthesis. Besides corticosterone, 11 beta-hydroxy-4-androstene-3,17 dione has been used as a substrate. Of all drugs studied, quinapril, dihydralazin, trandolapril, metipamid, methyldopa, betaxolol only appeared to be weak inhibitors of 11 beta-hydroxysteroid dehydrogenase, with an inhibitory activity 10-28% of that of glycyrrhetinic acid. Using corticosterone as a substrate, epitestosterone displayed a weak inhibitory activity with Ki 850, 1200 nmol/l and Vmax 2420, 3900 nmol/l.min for renal and testicular enzyme, respectively. In contrast to kidneys, the testicular 11 beta-hydroxysteroid dehydrogenase accepted also 11 beta-hydroxy-4-androstene-3,17-dione as a substrate, which could be inhibited by epitestosterone (Ki 1490 nmol/l, Vmax 1150 nmol/l.min). The results represent further evidence for different substrate specificity of renal and testicular 11 beta-hydroxysteroid dehydrogenase. PMID- 9370119 TI - Raised plasma concentrations of parathyroid hormone related peptide in hypercalcemic multiple myeloma. AB - In order to clarify the pathogenesis of hypercalcemia in multiple myeloma, we measured plasma levels of parathyroid hormone related peptide (PTHrP), tumor necrosis factor alpha (TNF-alpha), tumor necrosis factor beta (TNF-beta), intact PTH and, serum 1,25-dihydroxyvitamin D in fifteen patients of multiple myeloma. We also measured serum levels of inorganic phosphorus (iP) and alkalinephosphatase activity (ALP). No significant differences in iP (3.2 +/- 0.4 vs. 4.0 +/- 2.2 mg/dl), ALP (150 +/- 28 vs. 335 +/- 305 IU/l) 1,25(OH)2 D (31.5 +/- 17.0 vs. 23.3 +/- 11.2 pg/ml) or TNF-alpha (7.8 +/- 2.1 vs. 8.0 +/- 2.0 pg/ml) were observed between normocalcemic and hypercalcemic patients. Plasma iPTH levels in hypercalcemic patients were significantly lower than those in normocalcemic patients (28.5 +/- 9.4 vs. 16.3 +/- 5.6 pg/ml, p = 0.01). Plasma levels of TNF-beta were less than 15.6 pg/ml in all subjects. On the other hand, the frequency of patients with abnormally high plasma levels of PTHrP was significantly greater (2/9 for normocalcemia vs 5/6 for hypercalcemia, chi 2 = 5.20, p = 0.02) in patients with hypercalcemia than in normocalcemic patients. Furthermore, a significant positive relationship between plasma PTHrP levels and corrected serum calcium levels (cCa) was observed using Spearman's correlation analysis by rank in fifteen myeloma cases (rs = 0.66, p = 0.013). These results suggest that PTHrP might be involved in the elevation of serum calcium levels in hypercalcemic myeloma patients. However, a few cases exhibit normocalcemia despite elevated plasma PTHrP levels or hypercalcemia without high plasma PTHrP levels. Therefore, further studies are necessary to elucidate the pathogenesis of hypercalcemia in multiple myeloma. PMID- 9370120 TI - Relative deficiency in circulating levels of insulin-like growth factor I (IGF-I) during long-term treatment with a GnRH agonist. PMID- 9370121 TI - Regulation of hepatic lipase secretion from Hep G2 cells by ACTH and corticosteroids. PMID- 9370122 TI - Endothelial and epithelial cells: general principles of selective vectorial transport. AB - Endothelial and epithelial cells are both barriers and bridges between different compartments. This contribution discusses the general principles of paracellular, transcellular, and transmembrane transport with special emphasis on the relation between asymmetry and net movement of small solutes. Asymmetry of cell membrane transport properties is found in both epithelial and endothelial cell layers and provides the basis for transcellular transport. Furthermore, the asymmetry of membrane transporters such as the blood-brain barrier GLUT1 and the renal sodium glutamate cotransporter is discussed with regard to their different properties at the extra- and intracellular face. These molecular asymmetries play an important role in the efficiency, direction, and regulation of transport processes across the plasma membranes in endothelial and epithelial cells. PMID- 9370124 TI - Fluid exchange across endothelium. AB - The fluid pathway between plasma and lymph comprises 3 matrices of biopolymer chains arranged in series (endothelial glycocalyx, basement membrane, interstitial matrix), each of differing area, thickness, density and biochemical composition. Fluid exchange obeys the Starling principle but the 'balance' of pressures commonly favours filtration even 'downstream', and not venular reabsorption as still widely mistaught. At tissue level the maintenance of fluid balance remains controversial. The 3-pore theory is reviewed and updated following aquaporin characterisation. The permeability of the endothelial layer can be altered by both intracellular (Ca2+i and cyclic nucleotides) and extracellular mechanisms (albumin, orosomucoid), leading to gross 'hole' formation through as well as between cells (inflammatory stimuli) or more subtle changes (e.g. atrial natriuretic peptide). This is currently a fertile zone of interaction between classical physiology and molecular studies. PMID- 9370123 TI - Physiology and cell biology of the endothelium: a dynamic interface for cell communication. AB - This manuscript presents a brief overview of the physiology and cell biology of the endothelium, which is the basis for understanding the role of endothelial cells in pathological processes as diverse as atherosclerosis, tumour intravasation and multiple organ failure. Following consideration of general aspects of endothelial function in regulating haemostasis, vascular tone and growth, special emphasis will be placed on endothelial regulation of the inflammatory response, which centres on the microcirculation. A particular role in inflammation is played by cell adhesion molecules (CAM), expressed both on endothelial and blood cells. Cell and molecular biological methods to investigate the expression of CAM in endothelial cells in vitro will be presented, as well as novel data, indicating that cytokine-induced up-regulation of CAM in the endothelium may involve signal transduction pathways other than those culminating in the activation of NF-kappa B. Finally, the phenomenon of angiogenesis will be briefly reviewed as a characteristic of endothelial cell activity of central importance to both physiology and pathology and new experimental data presented from an in vitro model to study the ability of individual endothelial cells to form vessel-like structures. In comparative studies to investigate the roles of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor, the dominant role of VEGF in the formation of capillary networks could be unequivocally demonstrated. PMID- 9370125 TI - Shear stress, the endothelium and the balance between flow-induced contraction and dilation in animals and man. AB - Dilation is the most commonly observed diameter change in blood vessels when intraluminal flow increases. However, at very high and low levels of vascular tone the response is constriction. This complex response seems designed to ensure that time-averaged vascular tone levels are restricted to an intermediate range. Flow dilation is initiated predominantly at the surface of the endothelium, probably by conformational change in macromolecules of the extracellular matrix such as glycosaminoglycans. This is associated with changes in ion binding--flow is exquisitely sodium sensitive, and subsequent alteration in cellular function. In the rabbit basilar artery the inward rectifying potassium channel of the endothelium cell is opened by shear stress increase leading to dilation and the voltage-dependent calcium channel of the smooth muscle cells with constriction. In this blood vessel, at any rate, the final response to flow change seems to be predominantly the consequence of the interaction between these two processes. PMID- 9370126 TI - The role of the endothelium in inflammation and tumor metastasis. AB - In inflammation, cells interact with extracellular matrices or neighboring cells by a spatio-temporal intervention pattern of specific cell surface receptors and adhesion molecules. Resident cells of the injured tissue communicate with circulating effector cells by cytokines and direct cell-cell contact. These cytokines stimulate expression of the adhesion molecules ICAM-1, VCAM-1, and E- and P-selectin on endothelial cell surfaces and upregulate beta 2-integrins and ICAM-1 on luminal leukocytes. White blood cells then adhere to the activated endothelial cells, migrate through the vessel wall, and penetrate areas of infection or tissue damage. The basis for a cellular immune response is formed by the interaction between T lymphocytes and antigen-presenting cells amplified by adhesion molecule LFA-1,2,3 to ICAM-1 binding. PMID- 9370127 TI - Endothelium and high blood pressure. AB - Due to its strategic anatomical position, the endothelium is constantly exposed to the different risk factors for atherosclerosis. During the last decade it has become clear that hypertension profoundly affects endothelial function. Depending on the form of hypertension, endothelium-dependent relaxation is impaired in most vascular beds. In spontaneous hypertension, the production of nitric oxide, which in endothelial cells is formed from L-arginine via the constitutively expressed enzyme endothelial nitric oxide synthase, represents the main mediator of endothelium-dependent vasodilation and seems to be enhanced. On the other hand, the release of endothelium-dependent contracting factors such as prostaglandin H2 and thromboxane A2 have been demonstrated in this model of hypertension. Similar results have been obtained in the forearm circulation of patients with essential hypertension. In contrast, in models of salt-sensitive hypertension no release of vasoconstrictor prostanoids can be found indicating a decreased production of nitric oxide. Thus, in spontaneous hypertension an increased production of nitric oxide seems to occur, which is ineffective due to either the simultaneous release of endothelium-dependent vasoconstrictors and/or inactivation of nitric oxide, or due to anatomical changes such as hypertension-induced intimal thickness which inhibits its action on vascular smooth muscle cells. In summary, in hypertension, endothelium-dependent vasodilation is blunted and the endothelial L-arginine nitric oxide pathway is altered. These changes seem to represent a consequence rather than a cause of hypertension. PMID- 9370128 TI - The adventitia, endothelium and atherosclerosis. AB - Despite many theories, the initiating circumstances for the development of atherosclerosis remain obscure. The development of animal models of atherosclerosis was based upon the different theories of the origins of atherosclerosis which suggested that it originates at the intimal surface of the vessel. A more recent model of atherosclerosis involves perivascular manipulation of the vessel by positioning of a hollow silastic collar around the artery. In this model, several of the features seen in early human atherosclerosis are generated within a period of 7 days. It is hypothesized that arterial wall hypoxia following occlusion of the vasa vasorum may be the initial lesion of atherosclerosis, and hence that in some cases atherosclerosis is a disease of the outer layers of the arterial wall. PMID- 9370129 TI - [Lymph node dissection for T1 esophageal cancer]. AB - Proper mucosal cancer of esophagus of esophageal has no lymph node metastasis, and lymph node metastasis occurs when the tumor invades to muscularis mucosa. Submucosal cancer of esophagus has lymph node metastasis in the rate of 44.4% (40/90). The incidence and number of metastatic lymph node increase with the depth of invasion. Lymph node metastasis of esophageal cancer spreads widely to cervix, mediastinum and abdomen. It's same in submucosal cancer and first metastasis occurs also appears at everywhere from cervix to abdomen. There are high rate of lymph node metastasis in 101L, 105, 106rR, 106rL, 108, 110, 1, 2, 3, 7 lymph nodes. The cancer in upper thoracic esophagus has high rate of lymph node metastasis in cervix and upper mediastinum and lymph node metastasis of lower thoracic esophageal cancer is liable to appear in lower mediastinum and abdomen. Then the cancer in middle thoracic esophagus should be performed the lymph node dissection in cervix, mediastinum and abdomen, especially 101, 102m, 104, 105, 106r, 106t, 107, 108, 110, 1, 2, 3, 7 lymph nodes. On the other hand, cancers limited to proper mucosal layer should be treated with endoscopic mucosal resection. And its same as in the greater part of cancers invaded to muscularis mucosa and shallow layer of esophageal submucosa. The 5 year survival rate of T1 cancers of esophagus is 85.6%, which were performed surgical treatment. PMID- 9370130 TI - [Necessity of cervical lymph node dissection by retrospective analysis of submucosal cancer in mid-thoracic esophagus]. AB - The frequency and distribution of metastatic lymph node of submucosal cancer (sm) located in mid-thoracic esophagus were investigated retrospectively to evaluate the significance of cervical lymph node dissection, so-called "radical neck dissection". In the further investigations of lymph node dissection in sm cancer located only in mid-thoracic esophagus, cervical lymph node metastasis was found only in 2 cases of 19 mid-thoracic esophageal sm cancer, which were both at paraesophageal area, resectable from the thoracic approach. Comparison of the survival cases receiving esophagectomy for sm cancer located in mid- and lower esophagus, with cervical lymph node dissection (n = 26) and without (n = 16) showed no significant differences. Therefore cervical lymph node dissection can be omitted in cases of mid-thoracic esophageal sm cancer. PMID- 9370131 TI - [Operative procedures of T1 cancer of the lower thoracic esophagus]. AB - Pathological results for 70 cases of T1 EiEa esophageal cancer resected in our department for the past 12 years, have shown 32 cases of mucosal cancer and 38 cases of submucosal cancer. Lymph node metastasis was recognized in 21 cases (30%). Moreover, positive nodes were observed only in submucosal cancer cases. Lymph node metastasis was mainly observed in the lower mediastinum and in the upper abdomen. However, it was frequently observed in the upper mediastinum (106) and sometimes in the supraclavicular area (104). The lymph node dissection should be performed in the mediastinum through the upper abdomen and neck. The subtotal esophagectomy with thoracotomy and the systematic dissection is common operative procedures, but the reduced surgery, i.e. transhiatal esophagectomy or the lower esophagectomy and proximal gastrectomy, is also indicated in some cancer patients. PMID- 9370132 TI - [Reasonable lymph node dissection for T2 or T3 midthoracic esophageal cancer with cervical lymph-node metastasis]. AB - In order to determine the reasonable lymph node dissection for T2 or T3 midthoracic esophageal cancer with cervical lymph node metastasis, a retrospective study was carried out on 106 patients receiving resection between 1983 and 1996. Metastasis to cervical lymph node was obtained in 27.4% (29/106) of patients with T2 or T3 midthoracic esophageal cancer. Within 29 patients, metastasis in cervical node only, in two fields and in three fields occupied 17.2%, 41.4% and 41.4%, respectively. And according to the histologic examination of dissected lymph nodes, metastatic sites spreaded from neck to perigastric region. Five-year survival rate of 23 patients receiving curative operation was 33.0%, and that of 13 patients excluding 3-field metastasis was 51.9%. But the main sites of nodal recurrence were cervical or superior mediastinal nodes along the bilateral recurrent laryngeal nerves, and the rate of nodal recurrence was 47.8%. These results of actual state of lymph node metastasis and prognostic benefit of aggressive dissection suggest that 3-field lymph node dissection is mandatory for T2 or T3 midthoracic esophageal cancer with cervical lymph node metastasis. And we should endeavor to upgrade the precise dissection in order to decrease the nodal recurrence. PMID- 9370133 TI - [Rational lymphadenectomy in patients with cervical nodes metastasis for carcinoma of the lower third esophagus]. AB - Prognostic value of removing cervical nodes in patients with carcinoma of the lower third esophagus is extremely controversial. Of 93 patients with curative esophagectomy via trans-thoracic approach, cervical nodes were involved in five patients (13%), upper mediastinal nodes in 12 patients (30%), and para-aortic nodes in only one patients (3%) for 40 patients whose proximal part of the tumor invading the mid-esophagus from below. Of the remaining 53 patients with tumor extent confined to the lower third esophagus, cervical nodes were involved in only one patients (2%), upper mediastinal nodes in five patients (9%), and paraaortic nodes in six patients (11%). Three of the five patients with cervical metastasis whose proximal part of the tumor invading the mid-esophagus survived for at least 22 months or more following three-field lymphadenectomy. Removing the cervical nodes in patients with carcinoma of the lower third esophagus may have some role to improve the survival if the tumor invades the mid-esophagus from below. PMID- 9370134 TI - [Strategy of lymph nodes dissection for the lower thoracic esophageal cancer without metastasis to the upper-mediastinal lymph nodes]. AB - The incidence of metastasis to the lymph nodes in preoperative untreated patients with Ei, T2 or T3 esophageal cancer is 70.7% (41 of 58 cases) in our institute. Especially, a high incidence of metastasis to the abdominal lymph nodes has been noted. In contrast, metastasis to the cervical lymph nodes is not common. The majority of recurrence appear as a distant metastasis to the liver, lung or bone through the hematogenic route. However, recurrence in the peritoneum through the lymphatogenic route is not uncommon. Therefore, current strategy of lymph nodes dissection for esophageal carcinoma would be inadequate for the complete inhibition of recurrence, so that chemotherapy remains to be needed. Since the diagnostic procedure with ultrasonographic endoscopy and computerized tomography is highly accurate for the assessment of metastasis to the uppermediastinal lymph nodes, operative procedure suitable for each case should be determined on the basis of preoperative examination. PMID- 9370135 TI - [Rational extent of lymph node dissection for carcinoma of the lower third of the thoracic ESOP-hagus of T2 or T3 stage with abdominal lymph node metastasis]. AB - We discussed the rational extent of the lymph node dissection for carcinoma of the lower third of the esophagus of T2 or T3 stage with abdominal lymph node metastasis. Lymph node metastasis developed in 89.5% of patients. Cervical lymph node metastasis was seen in 35.8%. In the cases with positive abdominal lymph node, 40.9% of the patients had cervical node metastasis. The most frequent site of the positive node in the neck is the area along the right recurrent laryngeal nerve. On the stand point of removal of metastatic lymph node, neck dissection should be required. Three-field dissection yielded better survival rate than two field dissection but statistical significance was not obtained. When the patients have cervical lymph node metastasis, they have greater possibility of developing blood borne metastasis. However, this observation does not deny the validity of the three-field dissection. Because this dissection may help reducing nodal spread and nodal recurrence. We have to wait for accumulation of the patients to analyze the definite extent of node dissection for T2 or T3 stage of carcinoma of the lower third of the esophagus with positive abdominal lymph node. PMID- 9370136 TI - [Neoadjuvant chemotherapy and concurrent radiochemotherapy for advanced esophageal carcinoma potentially invading adjacent structures]. AB - Advanced esophageal carcinoma invades adjacent structures, and its resection without residual tumor is difficult. Preoperative chemotherapy and combined modality therapy are being tried to improve survival in patients with T4 esophageal carcinoma. For these cases, chemotherapy with 5-fluorouracil and cisplatin (FP) is known to be not so effective. For 17 patients with T4 esophageal carcinoma in 2 institutes, treated primarily with chemotherapy with 5 fluorouracil, cisplatin and adriamycin (FAP), the response rate was 76%. Operation was performed in all of them after 2-3 courses of FAP, and curative resection without resection of adjacent structure was carried out in 14 cases (82%). Treatment with FP concurrent with more than 50Gy of radiation (CRT) was effective for patients with T4 esophageal carcinoma, its response rate was 72.80% in Japanese literature, and resectability rate was 37-48% after treatment. All of our 3 cases had partial response, but resection was not performed because patients refused surgery. Phase II trial of neoadjuvant chemotherapy followed by concurrent chemotherapy plus high-dose radiation therapy was carried out for 45 patients with clinical stage T1-4N0-1M0 in an attempt to improve the result of concurrent chemoradiation in America (RTOG), and the overall median survival was 20 months. But this treatment will not be used, because treatment-related death was seen in 10%. We think that FAP and CRT are the most effective neoadjuvant therapy in patients with T4 esophageal carcinoma. If curative resection is possible after treatment, operation should be done to improve prognosis. PMID- 9370137 TI - [Salvage surgery for the T4 esophageal cancer following downstaging by neoadjuvant chemoradiotherapy]. AB - The standard modality of the treatment for the patients with T4 esophageal cancer, whose prognosis still remains quite poor, is not established yet. Salvage surgery for the T4 esophageal cancer following downstaging by neoadjuvant chemo radiotherapy has become to be available. During the period from 1992 to 96, 30 patients with the suspected T4 esophageal cancer underwent chemoradiotherapy, which consisted of two courses of CDDP/5-FU with-sequential or concurrent 50-60Gy radiotherapy. Among them eleven patients became to be resectable by means of thoracotomy and laparotomy and pathological CRs were obtained in either primary lesions or lymph nodes. The longest survival term following surgery is 36 months. Three patients died of cancer recurrence including the organ metastasis and one died from pyothorax without cancer due to severe immunosuppression attributable to chemoradiation. Our results warrants further studies of neoadjuvant chemoradiotherapy for the patients with T4 esophageal cancer. PMID- 9370138 TI - [Esophagectomy combined resection of invaded neighboring organs for T4 esophageal carcinoma]. AB - Advanced esophageal cancer, which invades into neighboring organs are classified as T4 esophageal cancer. Thoracic descending aorta, tracheobronchial tree, lung and pericardium are organs frequently invaded from esophageal cancer. Extended operation with combined resection of invaded neighboring organs such as aorta or tracheobronchhial tree were thought to be difficult and had high postoperative complications rates, mortality rates and poor prognosis. Therefore, this type of operation were not performed in the past except a few cases. However, recent progress in the fields of cardiovascular or general thoracic surgery, aortic replacement or tracheobronchial reconstruction become safety operation at present. Reports of extended operation of aortic or tracheobronchial resection for T4 esophageal cancer are increasing. Patients with T4 esophageal cancer are expected to have long term survival from extended operations when their cancer have no distant metastasis, and no or minor regional lymph node metastasis, are resected completely by combined resection of invaded neighboring organs, and responders to preoperative chemo and/or radiotherapy. Extended operation for T4 esophageal cancer will be considered as curative operation for very selected patients and improve the survival of the patients in the future. PMID- 9370139 TI - [My device for operation of esophageal and gastric cancer]. AB - I employed esophageal reconstruction prior to esophagectomy as a standard surgical procedure. In this procedure, two separate teams perform the operation in the cervical and abdominal regions simultaneously, therefore the operation time is shortened, and we can estimate the degree of lymph node and distant metastasis in each area early in the operation. I applied free ileocolon transfer to 5 patients with cervical esophageal cancer because of voice restoration combined with reconstruction of cervical esophagus. They were able to achieve a fair to good voice, to swallow without aspiration. Since the founding of our institute, we have performed 185 esophagectomies with an operative death rate of 4.3% and 5-year survival rate of 20.4%. I employed ileocolon interposition as a reconstruction in 55 patients after total and proximal partial gastrectomy. In this procedure, reflux esophagitis is prevented by the Bauhin's valve and the colonic segment functions as a gastric reservoir. PMID- 9370140 TI - [Paths of innovative surgery in gastrointestinal cancer in our department]. AB - Our Department of Surgery was founded in 1982 by Prof. Inoko who performed reportedly the first gastrectomy for gastric cancer in Japan. Prof. Mine developed the auto-suture device which was world first one in 1958. We have carried out novel therapeutic methods for metastases and invasions in gastrointestinal cancer. For the management of lymph node metastasis, we developed emulsion and activated carbon particles containing anticancer agents which were selectively delivered to lymph nodes. Activated carbon particles visualized the regional lymph nodes as blackened nodes which can be easily dissected at time of surgery. Mitomycin C bound to carbon particles was effective for prophylaxis and treatment of peritoneal metastasis in prospective randomized control study. For prevention of postoperative local recurrence of rectal cancer, we developed preoperative 3 combined treatments with radiation, hyperthermia and 5-Fluorouracil suppository therapy. This 3 combined treatments resulted in improvement of survival and decreasing the local recurrence. For the new challenge to metastasis we have tried to apply the monoclonal antibody drug conjugate, angiogenesis inhibitor and immuno-guided surgery. PMID- 9370141 TI - Supplementation with antioxidants prior to bone marrow transplantation. AB - Conditioning therapy preceding bone marrow transplantation (BMT) usually consists of high-dose chemotherapy and total body irradiation (TBI). It has acute and delayed toxic effects on several tissues, possibly related to peroxidation processes and exhaustion of antioxidants. Early studies indicated an increase of peroxide processes and a decrease of antioxidants during conditioning therapy. Hence, we investigated the effect of antioxidant supplementation on peroxidation processes and antioxidant status. We supplemented a patient group (N = 16) [BMT (+)], with oral 45 mg beta-carotene, 825 mg alpha-tocopherol and 450 mg ascorbic acid daily for three weeks before conditioning therapy. Another patient group (N = 10), BMT(-), was not supplemented with antioxidants before conditioning therapy. In order to investigate the physiologic effect of supplement antioxidants a healthy control group (N = 10) was supplemented with the same doses as BMT(+). Peroxide concentrations in plasma were measured by using the cholesterol oxidase (CHOD)-iodide method and antioxidants were measured by HPLC. Before supplementation the beta-carotene and alpha-tocopherol concentrations were comparable in both patient groups. After supplementation significantly higher beta-carotene and alpha-tocopherol concentrations were measured in the supplemented patients, BMT(+), than in the unsupplemented patients, BMT(-). After conditioning therapy, BMT(+) patients showed a significantly higher beta-carotene concentration (p < 0.05) than before supplementation. In BMT(-) patients the beta carotene (p < 0.05) and alpha-tocopherol concentrations (p < 0.01) decreased significantly and the lipid peroxide concentration increased significantly following conditioning therapy. We conclude that antioxidant supplementation prior to conditioning therapy reduces peroxidation processes induced by conditioning therapy in bone marrow recipients. PMID- 9370142 TI - Clinical, biochemical, and histological changes in hepatitis C virus infection associated cryoglobulinemia. AB - The most common extrahepatic manifestation of HCV infection is mixed cryoglobulinemia (MC). 62 unselected patients with chronic HCV infection were prospectively evaluated for the presence of cryoglobulinemia and associated clinical and biochemical parameters. Furthermore, a putative relationship between the HCV genotypes and cryoglobulinemia was tested. Histological features typical for HCV infection were comparatively analyzed in cases with and without cryoglobulinemia. Whether an intrahepatic Th2-response is responsible for the strong antibody production causing cryoglobulinemia was also examined. Cryoglobulins were detected in sera of 30 patients (approximately equal to 48%). Patients with cryoglobulinemia were on the average elder, showed an apparent longer duration of infection, and suffered more frequently from arthralgia, accompanied by a significant increase of total serum IgM concentration and rheumatoid factor activity. The HCV genotype distribution among patients with cryoglobulinemia was not different from that found in patients without cryoglobulinemia. In cases with cryoglobulinemia, an increased activity of chronic hepatitis and a higher grade of liver fibrosis was noted. The prevalence of HCV-typical histological lesions among all patients were: Portal lymphocytic aggregates (40%), bile duct damage (35%), steatosis (47%), and intracellular acidophilic bodies (29%). A significant correlation, however, could not be found between cryoglobulinemia and the presence of HCV-typical histological lesions. An intrahepatic Th2-response causing an increased antibody production could not be observed in cases with cryoglobulinemia. PMID- 9370143 TI - A case of Behcet's syndrome presenting with Dieulafoy's ulcer. AB - Behcet's syndrome represents a multisystemic disease with vasculitic changes. We here describe a patient with Dieulafoy's ulcer and oral, genital and bronchial mucosal lesions who met the criteria of incomplete Behcet's syndrome. The rare observation of Behcet's syndrome presenting with Dieulafoy's ulcer in our patient raises the question as to whether this type of ulcer, usually caused by a developmental malformation of a submucosal gastric artery, may occasionally be due also to submucosal aneurysms that result from a vascular inflammation. PMID- 9370144 TI - Lactulose--a multifaceted substance. AB - Lactulose is therapeutically used in hepatic encephalopathy, constipation, and salmonellosis. This semisynthetic disaccharide is neither metabolized nor absorbed in the normal small intestines. Comparable to plant-polysaccharides lactulose is bacterially fermented in the colon to short chain fatty acids and gases. Major consequences are a drop in pH and a change in composition and metabolic activity of the colonic flora. These and other potential effects suggest complex mechanisms of action of lactulose, with the potential for additional indications in diagnosis and therapy. The use of lactulose as substrate for the H2-breath-test is well known as a means for the measurement of oroeceal transit time and as test for small intestinal bacterial overgrowth. An extension of the diagnostic potential is given by the assessment of the permeability in diffuse intestinal disease with combined disaccharide/monosaccharide test solutions, especially in Crohn's disease. Explanations for positive effects in the prophylaxis of cholesterol-gallstones, in the therapy of hypercholesterolemia and in the prevention of colorectal adenoma and carcinoma can be found in changes in lipid- and bile acid metabolism found after lactulose ingestion. Lactulose may lead to an improved glucose tolerance in parallel to fibre and acarbose effects which involve several mechanisms of carbohydrate metabolism. Lactulose presumably reduces pathogenic bacteria in favor of the health promoting bifidusflora; also, production and absorption of endotoxines may be reduced; this suggests that lactulose may have therapeutic effects on both infectious and idiopathic inflammatory bowel diseases. Numerous studies with interesting but not as yet convincingly documented clinical relevance suggest that the many effects of lactulose may be interesting subjects for future research. PMID- 9370145 TI - Beliefs about genetic influences on mathematics achievement: a cross-cultural comparison. AB - The poor mathematics performance of children in the United States has become a topic of national concern. Numerous studies have shown that American children consistently perform worse than their counterparts in many parts of the world. In contrast, children in China, Japan, Taiwan, and other Asian countries consistently perform at or near the top in international comparisons. This paper examines possible causes of the poor performance of American children and the excellent performance of Asian children. Contrary to the beliefs of many Americans, the East Asian advantage in mathematics is probably not due to a genetically-based advantage in mathematics. Instead, differences in beliefs about the role of genetics may be partly responsible. Asians strongly believe that effort plays a key role in determining a child's level of achievement, whereas Americans believe that innate ability is most important. In addition, despite the relatively poor performance of their children, American parents are substantially more satisfied with their children's performance than Asian parents. The American emphasis on the role of innate ability may have several consequences for children's achievement. For example, it may lead children to fear making errors and to expend less effort on mathematics than their Asian counterparts. As research on genetic influences on behavior, traits, and abilities increases scientists should be careful to ensure that the public understands that genetics does not directly determine the exact level of a child's potential achievement. PMID- 9370146 TI - Adjustment of reduced arterial blood pressure--a tool for investigations into gradually reduced brain function. AB - Hypoxic-ischemic disorders of the neonatal brain function depend in particular on critical decrease of arterial blood pressure (ABP) below the limited range of cerebral autoregulation. An experimental design including an extracorporal ABP controller is presented which enables the induction of gradual hemorrhagic hypotension at different stages of blood flow reduction up to stages of critically disturbed systemic and regional hemodynamics and oxygen supply. In nine newborn piglets several levels of critically reduced ABP (60, 50, 40, 35 mmHg, normal about 75 mmHg) were stabilized over 30 min, and heart rate, breathing, blood gases, systemic and cerebral hemodynamics, and electrocorticogram were recorded. It was found that the reduced circulating blood volume was redistributed in favour of the vital organs. Therefore, brain cortical blood flow was slightly increased at ABP = 60 and ABP = 50 mmHg. A significant reduction of cortical blood flow occurred only at ABP = 35 mmHg. The experimental design which was based on an extracorporal ABP controller is necessary and sufficient for producing functional states of gradual hemorrhagic hypotension with high stability and accuracy, enabling a systematic study of disturbed regional hemodynamics and disturbed energy metabolism under steady state conditions, even under critically changed states of the systemic cardiovascular regulation. PMID- 9370147 TI - Pityrosporum yeasts--what's new? AB - The lipophilic yeast Pityrosporum ovale is a member of the normal human cutaneous flora in adults but also associated with several skin diseases. In pityriasis versicolor, under the influence of predisposing factors, P. ovale changes from the round blastospore form to the mycelial form. A great problem in pityriasis versicolor is the high rate of recurrence and to avoid this a prophylactic treatment is mandatory. Pityrosporum folliculitis is a chronic disease characterized by pruritic follicular papules and pustules located primarily on the upper trunk, neck and upper arms. In direct microscopy clusters of round budding yeast cells are found. The disease responds rapidly to antimycotic therapy. There are now many studies indicating that P. ovale plays an important role in seborrhoeic dermatitis. Many of these are treatment studies showing a good effect of antimycotics paralleled by a reduction in number of organisms. Severe seborrhoeic dermatitis often difficult to treat is associated with AIDS. In peripheral blood from a high number of patients with seborrhoeic dermatitis we found an increase in number of natural killer T-cells and decreased PHA and Con-A stimulation. Secondary we found low serum IgG antibody titres in patients compared to controls. Other studies have found a reduced lymphocyte stimulation reaction when lymphocytes from patients with seborrhoeic dermatitis were stimulated with a P. ovale extract. Additionally, IL-2 and IFN gamma production by lymphocytes from patients was markedly depressed and IL-10 synthesis were increased after stimulation with P. ovale extract. The majority of adult patients with atopic dermatitis localized to the head, neck and scalp are prick-test positive to a protein P. ovale extract. One study showed that p. ovale extracts increased IL-4, IL-10 and IgE synthesis in patients with atopic dermatitis. There are also treatment studies indicating that antifungal treatment may be beneficial in these patients. PMID- 9370173 TI - Vasopressin and water conservation: the good and the evil. PMID- 9370174 TI - Ambulatory blood pressure monitoring is a useful clinical tool in nephrology. AB - Hypertension is a key factor in the genesis and deterioration of many renal diseases and is also a risk factor for death in patients with end-stage renal disease. However, the standard methods of measurement are prone to variability, especially in patients undergoing dialysis. The technique of ambulatory blood pressure monitoring allows a better assessment of overall blood pressure levels and promises to assume a bigger role in the care of renal patients. Ambulatory blood pressure monitoring is widely used in hypertension trials, and the reports of several consensus meetings on the clinical uses of ambulatory blood pressure monitoring have been published. Two similar validation protocols now exist for ambulatory blood pressure monitors, and tables of population-based normal blood pressures for age and gender are available. The available evidence suggests that ambulatory blood pressure compared with blood pressure measured in the physician's office is better correlated to left ventricular mass in subjects with chronic renal disease. Furthermore, studies in subjects with chronic renal disease and those undergoing renal replacement therapy show that blood pressure control is suboptimal in many patients and that nocturnal blood pressure is generally higher than in control subjects. Further insights into overall blood pressure behavior in this population will certainly emerge in the future. PMID- 9370175 TI - Effects of excess PTH on nonclassical target organs. AB - The classical target organs for parathyroid hormone (PTH) are the bone and kidneys. In uremia, however, numerous studies have shown that PTH may also affect the function of a number of nonclassical organs and tissues besides the bone and kidney, including the brain, heart, smooth muscles, lungs, erythrocytes, lymphocytes, pancreas, adrenal glands, and testes. Most of these effects do not apply to the generally accepted actions or normal regulatory mechanisms of PTH. Thus, the potential role of PTH as one of the possibly many toxins in uremia is of current interest. The molecular basis for the actions of elevated PTH levels on various nonrenal and nonskeletal organs or tissues might be mediated via the widespread distribution of the classical PTH/PTH-related peptide (PTHrP) receptors and via the novel PTH2 receptors. The present survey deals with an evaluation of the nonrenal and nonskeletal effects of excess PTH in uremia, taking into consideration the presently available information on the organ specific expression of the classical and novel PTH receptors, and of the expression and function of PTHrP. PMID- 9370176 TI - Changing etiologies of unexplained adult nephrotic syndrome: a comparison of renal biopsy findings from 1976-1979 and 1995-1997. AB - Data compiled during the 1970s and early 1980s indicated that during these periods, membranous nephropathy was the most common cause of unexplained nephrotic syndrome in adults, followed in order of frequency by minimal-change nephropathy and focal segmental glomerulosclerosis (FSGS). However, we and others recently reported an increase in the incidence of FSGS over the past two decades, and the number of cases of FSGS diagnosed by renal biopsies in these centers now exceeds the number of cases of membranous nephropathy. Nonetheless, as a substantial fraction of patients with FSGS do not have the nephrotic syndrome, it remained unclear as to what extent the relative frequencies of FSGS and other glomerulopathies as causes of the nephrotic syndrome have changed over this time. To address this concern, we reviewed data from 1,000 adult native kidney biopsies performed between January 1976 and April 1979 and from 1,000 biopsies performed between January 1995 and January 1997, identified all cases with a full-blown nephrotic syndrome of unknown etiology at the time of biopsy, and compared the relative frequencies with which specific diseases were diagnosed in these latter cases between the two time intervals. The main findings of this study were that, first, during the 1976 to 1979 period, the relative frequencies of membranous (36%) and minimal-change (23%) nephropathies and of FSGS (15%) as causes of unexplained nephrotic syndrome were similar to those observed in previous studies during the 1970s and early 1980s. In contrast, from 1995 to 1997, FSGS was the most common cause of this syndrome, accounting for 35% of cases compared with 33% for membranous nephropathy. Second, during the 1995 to 1997 period, FSGS accounted for more than 50% of cases of unexplained nephrotic syndrome in black adults and for 67% of such cases in black adults younger than 45 years. Third, although the relative frequency of nephrotic syndrome due to FSGS was two to three times higher in black than in white patients during both study periods, the frequency of FSGS increased similarly among both racial groups from the earlier to the later period. Fourth, the frequency of minimal-change nephrotic syndrome decreased from the earlier to the later study period in both black and white adults. Fifth, the relative frequency of membranoproliferative glomerulonephritis as a cause of the nephrotic syndrome declined from the 1976 to 1979 period to the 1995 to 1997 period, whereas that of immunoglobulin A nephropathy appeared to increase; the latter accounted for 14% of cases of unexplained nephrotic syndrome in white adults during the latter study period. Finally, 10% of nephrotic adults older than 44 years had AL amyloid nephropathy; none of these patients had multiple myeloma or a known paraprotein at the time of renal biopsy. PMID- 9370177 TI - Mesangial phenotypic changes associated with cellular lesions in primary focal segmental glomerulosclerosis. AB - Injury to glomerular visceral epithelial cells has been proposed as the initial step in glomerular scar formation in primary focal segmental glomerulosclerosis (FSGS); however, the subsequent process that ultimately results in glomerular scar formation remains uncertain. This study examined whether phenotypically altered mesangial cells determine the early progression of primary FSGS. Cellular lesion characterized by proliferative epithelial cell reaction with occasional endocapillary hypercellularity has been considered to be an early morphologic feature in the development of glomerular scar in primary FSGS. We compared the immunohistologic findings of 10 patients with primary FSGS showing cellular lesion, 15 patients with primary FSGS showing only segmental scar, and 10 patients with minimal-change nephrotic syndrome. Histologically normal kidney tissue samples obtained from three patients with renal trauma were used as normal controls. Alpha-smooth muscle actin expression detected by a mouse anti-human monoclonal antibody as well as de novo type III collagen expression determined by a goat polyclonal antibody were prominent in the glomerular tufts with cellular lesions in FSGS patients. A significant increase in the number of glomerular CD68+ (a mouse anti-human monoclonal antibody) macrophages was also observed in association with the cellular lesion. Repeat renal biopsies in six of the 10 FSGS patients with a cellular lesion showed disappearance of the cellular lesion, reduced glomerular alpha-smooth muscle actin expression, decreased number of glomerular CD68+ macrophage, and progression of glomerular scar formation. These results indicate that mesangial cells undergo phenotypic changes to myofibroblasts in association with the cellular lesion in primary FSGS. Thus, the phenotypically altered mesangial cells acquiring features of a myofibroblast may have an important role in the early process of glomerular scar formation in certain types of primary FSGS. PMID- 9370178 TI - A randomized trial comparing cyclosporine induction with sequential therapy in renal transplant recipients. AB - Calcium antagonists may reduce the nephrotoxicity of cyclosporine (CsA), allowing CsA to be introduced immediately after renal transplantation and thereby obviating the need for sequential induction therapy with a monoclonal or polyclonal antibody. To test this hypothesis, in a pilot feasibility trial 100 cadaveric or one-haplotype-mismatched living-related renal transplant recipients were randomized to either (1) sequential therapy with anti-thymocyte globulin (ATG) (ATGAM; Upjohn, Kalamazoo, MI) 20 mg/kg/d for 7 to 14 days until renal function was established and CsA (Sandimmune; Sandoz, East Hanover, NJ) was started, or (2) CsA 8 mg/kg/d begun immediately before surgery with diltiazem (Cardizem; Marion Merrell Dow, Kansas City, MO) 60 mg sustained release twice daily. Acute rejection episodes during the first 90 days were not different with ATG versus CsA induction (42% v 28%; P = 0.142 by chi-square analysis). Graft failures (10% v 16%; P = 0.372) and the incidence of delayed graft function (28% v 34%; P = 0.516) were also similar with ATG compared with CsA. ATG caused lower platelet counts (138 +/- 59 x 10(3) v 197 +/- 75 x 10(3) at 7 days; P < 0.001) and lower white blood cell counts (9.6 +/- 4.6 x 10(3) v 12.3 +/- 4.9 x 10(3) at 7 days; P = 0.003). Diltiazem reduced the dose of CsA required to maintain target blood levels (479 +/- 189 mg/d v 576 +/- 178 mg/d at 14 days; P = 0.015). There were no statistically significant differences between the groups in serum creatinine levels at days 1, 3, 5, 7, 14, 28, 60, or 90. The results of this pilot feasibility trial suggest that prophylactic treatment with CsA and diltiazem may be equally effective and less toxic than ATG induction after renal transplantation. PMID- 9370179 TI - GFR determined by nonradiolabeled iothalamate using capillary electrophoresis. AB - Traditional measurements of glomerular filtration rate (GFR) in clinical practice include the measurement of serum creatinine or creatinine clearance. Increasing evidence concerning the limitation of these measurements in clinical practice and clinical trials has resulted in efforts to develop technologies that improve measurement of GFR. Recent efforts in that regard have used radioisotopic labeling of markers of GFR, such as 125I-iothalamate, and 51Cr ethylenediaminetetraacetic acid. Limitations of these technologies include radiation exposure as well as cost considerations for the management of radioisotopes, including safety, disposal, mailing, and deteriorating activity that results in short shelf life. We report a test that used 0.5 mL Conray dye injected subcutaneously and subsequent measurement of the nonisotopic (cold) iothalamate by capillary electrophoresis in blood and urine. GFR using cold iothalamate compared with standard clearance using 125I-iothalamate was 0.99. The method is cost-effective and allows for avoiding exposure to isotopes, as well as problems such as the disposal and short shelf life of isotopes. This technology could allow for replacement of 125I-iothalamate as a marker for GFR. PMID- 9370180 TI - Aluminum utensils contribute to aluminum accumulation in patients with renal disease. AB - Presently, aluminum utensils are widely used in the world, especially in the developing countries. However, whether aluminum leaching from such utensils contributes to aluminum accumulation or causes any damage in patients with renal disease remains unknown. We designed a prospective study to evaluate this problem. After excluding patients who were not examined at follow-up or who poorly complied during the study period, the opened randomized study consisted of 42 patients with chronic renal insufficiency (creatinine clearance <60 mL/min and >10 mL/min). All patients had not taken any aluminum-containing agents for 3 months, but used aluminum kitchen utensils for more than 1 year. Twelve patients comprised the control group; the other 30 patients comprised the study group. The aluminum kitchen utensils used by the study group patients were replaced with stainless steel utensils for 3 months, but those used by the control group were not. After 3 months, the decrements of serum aluminum (5.5 +/- 4.6 microg/L v 2.1 +/- 3.5 microg/L; P = 0.012) and daily urine aluminum excretion (14.3 +/- 15.2 microg/d v 2.1 +/- 5.6 microg/d; P = 0.005) in the study group patients were greater than those in the control group patients. The increments of transferrin saturation of the study group patients (1.8% +/- 9.5% v -3.7% +/- 9.5%; P = 0.052) were greater than those of the control group patients. In addition, the increments of iron (r = 0.368, P = 0.035) and transferrin saturation (r = 0.345, P = 0.049) positively correlated with the decrements of daily aluminum excretion in all patients. The study group patients with greater decrements of serum aluminum (>5.5 microg/L) had greater serum iron levels (90.2 +/- 27.7 microg/dL v 71.9 +/- 27.8 microg/dL; P = 0.047) and transferrin saturation (30.5% +/- 11.0% v 23.0% +/- 9.5%; P = 0.046) than those with less decrements of serum aluminum (<5.5 microg/L) after the study. Our study demonstrates that aluminum kitchen utensils may be the important aluminum exposure source for patients with chronic renal insufficiency who are not taking aluminum-containing agents, and hints that the long-term exposure of aluminum leaching from aluminum utensils probably affects iron levels in patients with chronic renal insufficiency. Further studies are clearly needed to confirm this observation. PMID- 9370181 TI - Prolonged therapy with ACE inhibitors induces a regression of left ventricular hypertrophy of dialyzed uremic patients independently from hypotensive effects. AB - Left ventricular hypertrophy (LVH), which frequently occurs in chronic uremia, may be due in part to factors other than arterial hypertension, chronic anemia, and/or other well-known loading conditions inherent to the uremic state. Angiotensin-converting enzyme (ACE) inhibitors may be able to reverse LVH by mechanisms independent of their antihypertensive effects. In this study, 18 subjects free of arterial hypertension or severe anemia were selected from 170 chronically hemodialyzed uremic patients after fulfilling the criterion of a supranormal left ventricular mass (LVM). Ten subjects agreed to undergo treatment with 2.5 to 20 mg lisinopril every other day over a period of 2 years, during which annual determinations of the LVM by echocardiography and of the 24-hour blood pressure with a portable device were carried out. Eight patients unwilling to undergo the treatment served as controls. The average resting left ventricular mass index (LVMi) of the overall group was 178 +/- 30 g/m2 body surface area (+/- SD), and did not differ between the two subgroups. Lisinopril treatment significantly decreased the LVM of eight of 10 treated subjects and actually even completely normalized it in three. The LVM of the untreated group remained unchanged. Systolic and diastolic blood pressures were 138 +/- 5 mm Hg and 78 +/- 6 mm Hg in the treated group and 133 +/- 9 mm Hg and 75 +/- 4 mm Hg in the untreated group, respectively (P = NS), and did not vary over the following 2 years. This study indicates that a mild degree of LVH, which is seemingly independent of arterial blood pressure load, does exist in a tight subset of uremic patients. This study also demonstrates that this type of LVH is apparently nonprogressive. ACE inhibitors given at doses not affecting blood pressure are able to reverse it. PMID- 9370182 TI - Impact of nitric oxide on blood pressure in hemodialysis patients. AB - Nitric oxide (NO) is a powerful vasoactive agent that contributes to the regulation of blood pressure (BP). However, the role of NO in uremic patients and during the course of hemodialysis is still debated. Blood L-arginine concentrations and exhaled NO concentrations were measured in 22 healthy controls and in 22 hemodialysis patients before and after dialysis. On the basis of their BP response during hemodialysis, the patients were divided into three groups: 6 of the 22 patients presented with a decrease in BP during dialysis (group 1), eight presented with a stable BP (group 2), and eight with an increase in BP (group 3). The exhaled NO concentration was higher in dialysis patients than in healthy controls (22.7 +/- 2.6 ppb in dialysis patients v 16.7 +/- 0.9 ppb in controls, mean +/- SEM, P = 0.044). The predialysis and postdialysis exhaled NO concentrations were inversely correlated with the change in BP during hemodialysis (r = -0.47, P = 0.013). Patients with a decrease in BP (group 1) had the highest NO concentrations; patients with an increase in BP (group 3) had the lowest values; and patients with a stable BP during the course of dialysis (group 2) had intermediary values (trend test, P = 0.0291). In addition, both the exhaled NO concentration and the blood L-arginine concentration decreased during dialysis in all patients (P = 0.005 and P = 0.001, respectively). These results provide several novel insights into NO metabolism and BP regulation during hemodialysis: (1) maintenance hemodialysis is associated with a chronic increase in NO concentrations; (2) changes in BP during hemodialysis are inversely correlated with exhaled NO concentrations, higher NO levels being associated with a decrease in BP and lower NO levels with an increase in BP during dialysis; (3) blood L-arginine levels decrease during hemodialysis, and this reduction may in turn influence NO production. PMID- 9370183 TI - Protein catabolic rate over lean body mass ratio: a more rational approach to normalize the protein catabolic rate in dialysis patients. AB - Protein catabolic rate (PCR), equivalent to dietary protein intake in "stable" dialysis patients, is widely accepted as a marker of their protein nutritional status. PCR is usually established from urea generation rate using urea kinetic modeling (UKM), but the normalizing factor is still a matter of controversy. By convention, PCR is expressed in grams of protein degraded daily divided by the dry body weight (BW) (nPCRBW). To be valid, this implies that dry BW is close to ideal BW and that body composition is preserved with a lean body mass (LBM) over BW ratio near 0.73. Such conditions being infrequently found in dialysis patients, it has been proposed to normalize PCR to ideal BW or to total body water, but these correction factors are not really appropriate. A more rational approach would be to express PCR as the ratio of protein degraded to the kilograms of LBM (nPCRLBM), thus offering the main advantage of directly coupling PCR to changes in protein or nitrogen reserve. In this study, we developed a combined kinetic model of urea and creatinine applied to the midweek dialysis cycle in 66 end-stage renal disease (ESRD) patients. UKM provided Kt/V and PCR, whereas creatinine kinetic modeling (CKM) was used to calculate LBM. Thirty-four patients with a preserved LBM (LBM/dry BW ratio equal to or greater than 0.70; mean ratio, 0.81 +/- 0.11) and with a dry/ideal BW ratio of 1.01 +/- 0.16 had a mean PCR of 1.14 +/- 0.30 g/kg/24 h when normalized to BW (nPCRBW) and of 1.40 +/ 0.30 g/kg/24 h when normalized to LBM (nPCRLBM). In the 32 patients with a reduced LBM (LBM/dry BW ratio, below 0.70; mean ratio, 0.60 +/- 0.09) and dry/ideal BW ratio of 1.11 +/- 0.23, the mean nPCRBW was 0.99 +/- 0.31 g/kg/24 h, whereas nPCRLBM was 1.62 +/- 0.32 g/kg/24 h. For both subgroups, Kt/V was similar, with mean values of 1.76 +/- 0.34 and 1.69 +/- 0.27. Normalizing PCR to LBM offers a double benefit: it compensates for the error induced by abnormal body composition (eg, obese patients) and permits PCR to be adjusted for the decrease in LBM that occurs with age. We propose nPCRLBM as a more rational index to express PCR in dialysis patients. PMID- 9370184 TI - Effect of two-chambered bicarbonate lactate-buffered peritoneal dialysis fluids on peripheral blood mononuclear cell and polymorphonuclear cell function in vitro. AB - Low pH, high osmolality, increasing glucose concentration, and glucose degradation products (GDP) formed during heat sterilization of conventional peritoneal dialysis (PD) fluids have been shown to have a detrimental effect on cells involved in peritoneal host defense. The two-chambered PD fluid bag in which glucose at pH approximately 3 is separated from a bicarbonate (25 mmol/L) lactate (15 mmol/L) buffer during heat sterilization permits PD fluids with lower GDP to be delivered to the patient at neutral pH. To establish the possible benefit of two-chambered bag PD fluids on peripheral blood mononuclear cell (PBMC) and polymorphonuclear (PMN) cell function, we compared conventional 1.5% Dianeal (1.5%D) with 1.5% two-chambered bag bicarbonate-lactate (1.5%D-B), and conventional 4.25% Dianeal (4.25%D) with 4.25% two-chambered bag bicarbonate lactate (4.25%D-B). Furthermore, to study the effect of the sterilization process on PBMC and PMN function, we compared filter-sterilized 4.25%D (4.25%D-F) with 4.25%D and 4.25%D-B. PBMC were harvested by Ficoll-Hypaque separation, and 2.5 x 10(6) cells in RPMI were incubated with an equal volume of the test fluids for 4 hours, pelleted, and resuspended in RPMI containing 10 ng endotoxin for a further 20 hours. Tumor necrosis factor alpha (TNF-alpha) production by endotoxin stimulated PBMC was not significantly different (P = 0.10) between 1.5%D-B and 1.5%D, but was significantly higher (P = 0.01) with 4.25%D-B compared with 4.25%D. PBMC exposed to filter-sterilized fluid (4.25%D-F) showed significantly higher endotoxin-stimulated TNF-alpha production compared with 4.25%D (P = 0.02), but was not significantly different from 4.25%D-B (P = 0.40). PMN were harvested by Ficoll-Hypaque separation and 10 x 10(6) cells incubated with test fluids for 30 minutes. After incubation, phagocytosis (phagocytosis index) was determined by the uptake of 14C-labeled Staphylococcus aureus, oxidative burst by reduction of ferricytochrome C to ferrocytochrome C on stimulation with PMA, and enzyme release by measurement of endotoxin-stimulated bactericidal/permeability increasing protein (BPI). Bicarbonate-lactate two-chambered fluids of similar osmolality and glucose concentration conferred a significant improvement in phagocytosis (P = 0.02 for 1.5%D-B and P < 0.001 for 4.25%D-B). Oxidative burst and BPI release were significantly higher in 4.25%D-B compared with 4.25%D (P < 0.001). Filter-sterilized 4.25%D-F conferred a significant improvement in phagocytosis and oxidative burst compared with 4.25%D (P < 0.001) or 4.25%D-B (P < 0.001). Furthermore, conventional 4.25%D was associated with significantly lower BPI release compared with 4.25%D-F (P = 0.01). GDP's acetaldehyde and 5-HMF were analyzed in 4.25%D-B, 4.25%D, and 4.25%D-F. Acetaldehyde was below the lower limit (0.79 ppm) of the standard curve in 4.25%D-B and 4.25%D-F fluids but was detected (3.76 to 5.12 ppm) in all of the 4.25%D fluids. Relative levels of 5-HMF in the 4.25%D-B (0.032 to 0.041 Abs @ 284 nm) and 4.25%D (0.031 to 0.036 Abs @ 284 nm) were similar. The lowest levels (0.001 Abs @ 284 nm) were observed in the filter-sterilized 4.25%D-F. The beneficial effects of two-chambered bicarbonate lactate-buffered PD fluids on PBMC and PMN function are probably related to reduction of GDP from heat sterilization of glucose in a separate chamber at a lower pH. This improvement in biocompatibility could have a beneficial affect on peritoneal defenses. PMID- 9370185 TI - Complications associated with insertion of jugular venous catheters for hemodialysis: the value of postprocedural radiograph. AB - It is routine in hemodialysis units to require a chest radiograph after the insertion of an internal jugular line for venous access before dialysis is commenced. There are two principal reasons for this: (1) to ensure that no procedural complications have occurred and (2) to verify correct catheter placement. Knowledge of the time delay involved may prompt nephrologists to opt for femoral access (with increased hemodialysis recirculation and need for repeated line placement). The benefit of the postprocedural chest radiograph has never been evaluated in the hemodialysis population. We retrospectively reviewed the data on internal jugular access placement from two large nephrology training centers. Over a 36-month period, 460 internal jugular dialysis catheters were placed in 312 patients. Wherever possible, 15-cm lines were used for the left internal jugular vein and 12-cm lines for the right internal jugular vein. Ultrasound guidance was used in 105 cases (22.8%). There were a total of 90 (19.6%) clinical complications in 62 patients (13.5%). These consisted of carotid artery puncture (n = 35, 7.6%) and hematoma (n = 55, 12%). All of these patients had a normal post-internal jugular chest radiograph. Carotid artery puncture did not occur if ultrasound guidance was used. There was no case of associated pneumothorax. Of the 370 line insertions in 250 patients in whom it was believed clinically that no complication had occurred, the chest radiograph only showed unsuspected line malposition in four cases (1.08%). Routine chest radiographs rarely contribute to the diagnosis of any procedural complications and are of little value after internal jugular access placement, especially if it is believed clinically that no complication occurred. PMID- 9370186 TI - Interleukin-1 receptor antagonist modulates the progression of a spontaneously occurring IgA nephropathy in mice. AB - Cytokines, such as interleukin-1 (IL-1), may play a key role in the pathogenesis of IgA nephropathy (IgAN). This study was conducted to evaluate the effects of IL 1 receptor antagonist (IL-1ra) in the treatment of a spontaneously occurring experimental IgAN in established phase. ddY mice (12/group) were injected twice daily with 3 mg/kg of IL-1ra, intraperitoneally, for 8 consecutive weeks. The placebo mice were injected with saline only. As normal controls, ddY mice, which were not treated with IL-1ra or saline, were killed at 6 weeks of age. Results showed a significant reduction of proteinuria in the IL-1ra-treated mice, compared with saline-treated mice (urinary albumin/creatinine, 0.24 +/- 0.04 v 0.39 +/- 0.03, P < 0.001). A significant improvement of renal 51Cr-EDTA (ethylenediaminetetra-acetic acid) clearance was observed in the IL-1ra-treated mice (t1/2, 12 +/- 2.7 minutes, compared with saline-treated mice 25 +/- 2.0 minutes, P < 0.001). Similarly, serum levels of creatinine (1.0 +/- 0.4 v 2.4 +/- 0.3 mg/dL, P < 0.001) and urea nitrogen (46 +/- 6 v 58 +/- 2 mg/dL, P < 0.01) were significantly lower in IL-1ra-treated mice than in saline-treated mice. In renal tissue studies, the IL-1ra-treated mice exhibited significantly decreased mesangial cell proliferation, compared with saline-treated mice (P < 0.001), as shown by light and electron microscopy. In addition, the IL-1ra-treated mice showed significantly lower glomerular expression of collagen type IV, fibronectin, laminin, and IL-6 (P < 0.001) than saline-treated mice, although they still showed higher glomerular expression of collagen type IV (P < 0.01), fibronectin (P < 0.01), laminin (P < 0.001), IL-1 (P < 0.001), and IL-6 (P < 0.01) than did normal control mice. Meanwhile, glomerular C3 deposition was significantly lower in IL-1ra-treated mice than in saline-treated mice (P < 0.001). These findings indicate that IL-1ra partially prevented the progression of spontaneously occurring IgAN in this experimental model. Data from these experiments also confirm the pathogenic effects of IL-1 in the established phase of IgAN in ddY mice. PMID- 9370187 TI - Renal accumulation and excretion of cyclic adenosine monophosphate in a murine model of slowly progressive polycystic kidney disease. AB - Evidence from in vitro studies indicates that increased proliferation of epithelial cells and secretion of fluid by these cells may be important factors in the progressive enlargement of renal cysts. The rate of cellular proliferation and fluid secretion by cyst epithelium in vitro can be strikingly accelerated by cyclic adenosine 3'5' monophosphate (cAMP) and agonists that lead to the production of this nucleotide. The extent to which renal cAMP content is increased in polycystic kidneys is unknown. In the current study, we determined the amount of this nucleotide in intact kidneys, cyst fluid, plasma, and urine in nonazotemic mice (DBA/2FG-pcy/pcy) with a slowly progressive form of inherited polycystic kidney disease (PKD). In 45 pcy/pcy mice studied 20, 45, or 70 days after birth, the total kidney cAMP content was 0.22 +/- 0.01, 0.46 +/- 0.02, and 0.90 +/- 0.05 pmol/mg tissue, respectively. By contrast, in 37 control DBA/2J mice the levels of cAMP at identical times remained relatively constant at 0.22 +/- 0.01, 0.21 +/- 0.01, and 0.29 +/- 0.01 pmol/mg tissue, respectively. In 70 day-old nonazotemic pcy/pcy mice with normal serum levels of parathyroid hormone, cAMP generated by the kidneys (nephrogenous cAMP) was 22.9 +/- 2.8 nmol/100 mL creatinine clearance, compared with 6.5 +/- 1.3 in normal animals of the same age (P < 0.001). The cyst fluids of 70-day-old pcy/pcy mice contained a lipid that increased transepithelial secretion of fluid by MDCK monolayers from a baseline of 0.012 +/- 0.002 to 0.136 +/- 0.008 microL/cm2/hr (P < 0.05). This lipid also stimulated cellular proliferation by monolayers of cultured MDCK and LLC-PK1 cells 2.5- and 7.9-fold (P < .05), respectively, and stimulated cAMP accumulation by these cells 1.6- and 2.0-fold (P < .05), respectively. These studies illustrate that renal cAMP production and excretion increase in concert with the cystic enlargement of the kidneys in DBA/2FG-pcy/pcy mice and identify a lipid cAMP agonist in murine renal cystic kidney disease. PMID- 9370188 TI - An 11-month-old with anti-glomerular basement membrane disease. AB - Anti-glomerular basement membrane antibody disease is an autoimmune disease that has rarely been described in children, and no cases have previously been described in a patient younger than 2.5 years of age. We report an 11-month-old infant girl who developed anti-glomerular basement membrane disease and progressed to end-stage renal disease and eventual renal transplantation. Although it has been suggested that this disease does not occur in infants, the possibility of anti-glomerular basement membrane disease must be considered in the differential diagnosis of acute renal failure and glomerulonephritis in an infant. The characteristic linear pattern of immunofluorescent studies for Immunoglobulin (Ig) G is important in suggesting the diagnosis, which can be confirmed by serologic testing for antibody titers. PMID- 9370189 TI - Appearance of immune complex glomerulonephritis following the onset of type I diabetes mellitus in a child. AB - Renal disease is a frequent late complication of type I diabetes mellitus, occurring almost entirely in adult patients. Typical diabetic nephropathy is characterized by proteinuria, and by the histological lesions of mesangial expansion and basement membrane thickening. We report an interesting case of a 3 year-old boy who developed immune complex glomerulonephritis with nephrotic syndrome 2 months after the onset of insulin-dependent diabetes mellitus. PMID- 9370190 TI - Posthysteroscopic hyponatremia: evidence for a multifactorial cause. AB - Hyponatremia, caused by absorption of hypotonic irrigating fluids, is a well documented complication of surgical procedures such as transurethral resection of the prostate (TURP). Although not commonly mentioned in the renal literature, there have been several case reports of hyponatremia associated with hysteroscopic endometrial ablation that also were considered to be attributable to absorption of hypotonic fluid. We present a 43-year-old white woman who underwent endometrial ablation for menorrhagia under general anesthesia. Postoperative serum chemistries showed a sodium of 112 mEq/L and an osmolality of 234 mOsm/L, and urine chemistries showed a sodium of 125 mEq/L and an osmolality of 629 mOsm/L. Although fluid retention of hypotonic irrigating fluid clearly contributed to the hyponatremia, search for associated morbidity showed an absence of either osmotic or volume stimulus to account for the apparent antidiuretic effect, suggesting the participation of a postsurgical, stress related ADH release. We conclude that hyponatremia associated with hysteroscopic endometrial ablation may be multifactorial. PMID- 9370191 TI - A role for uteroglobin in glomerulopathy: knockout mice as a model system. PMID- 9370192 TI - Progressive postinfectious glomerulonephritis with multiple tubuloreticular inclusions in an HIV-negative patient. PMID- 9370193 TI - Hungry bone syndrome after surgical parathyroidectomy. PMID- 9370194 TI - Proceedings of the Vth International Conference on Hormones, Brain, and Behavior (Torino, Italy, August 25-30, 1996). PMID- 9370195 TI - Estrogen regulation of GABA transmission in rat preoptic area. AB - The medial preoptic area represents a brain region where gonadal steroids act upon classical nuclear receptors to alter brain function. Of all the neuronal phenotypes shown to express estrogen receptors in the preoptic area, GABA neurones are the most abundant and known to be located in several nuclei of the medial preoptic area. Investigators utilising techniques capable of assessing endogenous GABA levels have shown that estrogen increases both basal and stimulated extracellular GABA concentrations within the preoptic area. Experiments have also shown that estrogen is able to modulate the actions of noradrenaline upon preoptic GABA neurones. The precise nature of estrogen's stimulatory influence on preoptic GABA concentrations is not understood fully but appears to involve changes in both the release and reuptake of GABA. As estrogen does not influence glutamic acid decarboxylase activity or gene expression in the preoptic area, the subcellular mechanism(s) through which estrogen enhances GABA release remain unknown. Recent investigations indicate that estrogen upregulates transcription of the GAT-1 GABA transporter gene in the preoptic area, and that this may contribute the stimulatory effect of estrogen on extracellular GABA concentrations. Further studies have identified effects of estrogen on GABA(A) receptor expression and ligand binding and, together with the above observations, demonstrate a coordinated and multifaceted upregulation of the preoptic GABA network by estrogen. It is suggested that estrogen acts directly upon GABA neurones expressing estrogen receptors to alter the dynamics of inhibitory transmission within specific neuronal networks of the preoptic area. This is likely to be of functional significance to the "feedback" influence of estrogen on the neural regulation of reproduction. PMID- 9370196 TI - Testosterone, preoptic dopamine, and copulation in male rats. AB - Steroid hormones prime neural circuits for sexual behavior, in part by regulating enzymes, receptors, or other proteins affecting neurotransmitter function. Dopamine facilitates male sexual behavior in numerous species and is released before and/or during copulation in three integrative neural systems. The nigrostriatal system enhances readiness to respond; the mesolimbic system promotes many appetitive behaviors; the medial preoptic area (MPOA) contributes to sexual motivation, genital reflexes, and copulation. We have reported a consistent relationship between precopulatory dopamine release in the MPOA, when an estrous female was behind a perforated barrier, and the ability to copulate after the barrier was removed. Recent, but not concurrent, testosterone was necessary for the precopulatory dopamine response and copulation. The deficit in MPOA dopamine release in castrates was observed in basal conditions as well as the sexual context. However, dopamine in tissue punches from castrates was higher than in intact males. Because tissue levels represent primarily stored neurotransmitter, dopamine appeared to have been synthesized normally, but was not being released. Amphetamine induced greater dopamine release in castrates, again suggesting excessive dopamine storage. The decreased release may result from decreased activity of nitric oxide synthase in the MPOA of castrates. A marker for this enzyme showed lower activity in castrates than in intact males. Finally, blocking nitric oxide synthase in intact males blocked the copulation induced release of dopamine in the MPOA. Therefore, one means by which testosterone may promote copulation is by upregulating nitric oxide synthesis in the MPOA, which in turn enhances dopamine release. PMID- 9370197 TI - Estrogen modulation of opioid and cholecystokinin systems in the limbic hypothalamic circuit. AB - The display of lordosis behavior has been correlated with the estrogen-induced expression of cholecystokinin (CCK) and enkephalin within the limbic-hypothalamic circuit. These neuropeptides have opposing effects on lordosis; for example, in the medial preoptic nucleus, CCK facilitates and opiates inhibit lordosis. Antisense oligodeoxynucleotide blockade of receptor expression indicated that CCK modulates lordosis in the medial preoptic nucleus through the CCK(A)-receptor. Sequence-specific antibodies directed against delta- and mu-opiate receptor proteins labeled fibers in the medial preoptic nucleus. Estrogen treatment of ovariectomized rats or etorphine (a nonselective opiate agonist) treatment altered the appearance of the immunoreactivity from a diffuse pattern to one of distinctly stained mu-opiate receptor immunoreactive cells and varicose fibers in the medial preoptic nucleus. Such a pattern of staining reflects an internalization of mu-opiate receptors following agonist stimulation. This type of internalization has been used as an indication of synaptic activity. The distribution of receptor internalization surrounds the distribution of CCK cells in the medial preoptic nucleus, suggesting that endogenous opioid peptides may modulate estrogen-induced CCK mRNA expression. Interestingly, nonselective and delta-opiate receptor selective antagonists potentiated the estrogen-induced CCK mRNA expression in the medial preoptic nucleus. Together, these results suggest that endogenous opioid peptides may modulate the estrogenic upregulation of CCK mRNA expression and demonstrate an important level of regulation of gene expression in which synaptic activity modifies hormonal input. PMID- 9370198 TI - Brain vasotocin pathways and the control of sexual behaviors in the bullfrog. AB - The neurohypophysial peptide arginine vasotocin (AVT) alters the display of several sexually dimorphic behaviors in the bullfrog (Rana catesbeiana). These behaviors include mate calling, release calling, call phonotaxis, and locomotor activity. Populations of AVT-immunoreactive cells are present in six areas of bullfrog brain and fibers are widespread. Neural areas involved in vocalization, in particular, contain AVT cells and fibers. As well, AVT concentrations in a subset of brain areas are sexually dimorphic and steroid sensitive. Effects of gonadectomy and gonadal steroid treatment vary, depending on the brain area and sex of the frog. For example, some anterior areas are sensitive to changes in both dihydrotestosterone (DHT) and estradiol. In some posterior brain areas, on the other hand, AVT levels are affected only by DHT. A similar situation exists for putative AVT receptors in bullfrogs. Receptors are widespread, occurring in many areas that have been linked to behavior. Receptor concentrations are sexually dimorphic in the amygdala pars lateralis, hypothalamus, pretrigeminal nucleus, and dorsolateral nucleus. Estradiol alters AVT receptor level in the amygdala of both sexes of bullfrog and both estradiol and DHT alter the receptor number in the pretrigeminal nucleus, but only in males. The mechanisms responsible for steroid effects on vasotocin neurons and their targets are unknown. Specific AVT cells, fiber terminal fields, and receptor populations are likely influenced by gonadal steroids for effective timing of individual behaviors displayed by bullfrogs. PMID- 9370199 TI - Regulation of aromatase gene expression in the adult rat brain. AB - Brain aromatase plays an important role in the regulation of adult reproductive behavior in male rodents. This report focuses on recent experiments from our laboratory that examined the distribution and regulation of aromatase mRNA in the rat brain. Aromatase mRNA was measured by a highly sensitive ribonuclease protection assay using a 32P-labeled antisense RNA probe that was complimentary to the 5' coding region of rat aromatase mRNA. This probe protects two RNA fragments in rat brain tissue: a 430-nt length fragment and a shorter 300-nt fragment. The presence of the 300-nt RNA fragment is not associated with enzyme activity in the rat brain and appears to represent an alternative brain-specific aromatase transcript whose function, if any, is unknown. In contrast, the 430-nt RNA fragment represents mRNA, which is thought to encode functional aromatase enzyme because its levels are correlated with aromatase activity concentrations in preoptic area, hypothalamus, amygdala, and ovary. Aromatase activity and mRNA levels in the preoptic area and hypothalamus decreased by 7 days after castration and were maintained at intact levels by treatment with testosterone and dihyhdrotestosterone, but not with estradiol. In contrast, neither aromatase activity nor mRNA levels in the amygdala are affected by castration or hormone replacement. In addition, sex differences in the regulation of aromatase mRNA were apparent in both the preoptic area and hypothalamus. These results demonstrate that androgens regulate the transcription or stability of aromatase mRNA in specific brain areas. Moreover, they suggest that gender differences in androgen responsiveness play an important role in regulating gene expression in the adult rat brain. PMID- 9370200 TI - The activity and expression of aromatase in songbirds. AB - Songbirds have emerged as extremely important animals for investigating sex steroid hormone effects on the central nervous system. The masculinizing effects of exogenous estrogen on the neural circuits controlling song in female zebra finches are well documented. There is evidence that estrogens are necessary for the full activation of singing behavior in several species. These kinds of studies have led us and others to investigate the mechanisms whereby estrogens are made available to the brains of songbirds during development and adulthood. In this article, I review results of some of these studies examining the estrogen synthetic enzyme aromatase and its expression and activity in brain and in other tissues of songbirds. I will discuss some results and thoughts we have about the interactions of aromatase with the two remaining androgen-metabolizing enzymes in the avian brain, 5alpha-reductase, the enzyme that converts T into the active androgen 5alpha-dihydrotestosterone (DHT); and 5beta-reductase, the enzyme that converts T into the inactive 5beta-DHT. Finally, I will consider some ideas raised by these studies concerning potential sources of the androgen substrate for brain aromatization as well as some possible new functions that aromatase might be playing in the songbird telencephalon. PMID- 9370201 TI - Steroid metabolism in the mammalian brain: 5alpha-reduction and aromatization. AB - Several steroid molecules, including androgens, estrogens, progestagens, and corticostereroids, are able to modulate the brain development and functions. These compounds are not always active in their own natural molecular configuration but they often need to be transformed at the level of their target cells into 'active metabolites'. The two major metabolic pathways that transform steroids in the brain are: the 5alpha-reductase-3alpha-hydroxy-steroid dehydrogenase and the aromatase pathways. Both are present in the brain and probably exert specific roles in the mechanism of action of hormonal steroids. In this article we briefly review some important findings achieved in our own and in other laboratories concerning the cellular and subcellular brain distribution, development, regulation, cloning, and molecular characterization of the involved enzymes. In particular, the recent identification of two isoforms of the 5alpha reductase, the type 1 and type 2, possessing different structural, biochemical, and distribution characteristics has attracted a considerable attention. The few data available on their brain distribution have been carefully considered. Finally, we have tried to focus on the role of the steroid metabolites in the brain, both when they interact with genomic and with membrane receptors. In particular, some unpublished observations on the effects of two 5alpha-reductase inhibitors on progesterone-induced anesthesia, a phenomenon mediated through the GABA(A) receptor, are presented. PMID- 9370202 TI - Sex differences in the vomeronasal system. AB - In the early eighties we found sex differences in the vomeronasal organ (VNO) and hypothesized that the vomeronasal system (VNS), a complex neural network involved in the control of reproductive behavior, might be sexually dimorphic. At that time sex differences had already been described for some structures that receive VNO input, such as the medial amygdala, the medial preoptic area, the ventromedial hypothalamic nucleus, and the ventral region of the premammillary nucleus. Since then, we have shown sex differences in the accessory olfactory bulb (AOB), the bed nucleus of the accessory olfactory tract (BAOT), and the bed nucleus of the stria terminalis (BST). When new VNS connections were found, all of them ended in nuclei that present sex differences. In general, sex differences in the olfactory system show two morphological patterns: one in which males present greater morphological measures than females, and just the opposite. To explain the morphometric measures of males in the latter, it has been hypothesized that androgens serve as inhibitors. Our work on the involvement of the GABA(A) receptor in the development of AOB and maternal behavior sex differences also suggests that neonatal changes in neuronal membrane permeability to the ion Cl- differences. This might be the first animal model to help us to understand the situation in which human genetic and gonadal sex do not agree with brain and behavioral sex. Finally, we stress that sex differences in the VNS constitute a neurofunctional model for understanding sex differences in reproductive behaviors. PMID- 9370203 TI - Neural control of maternal behaviour and olfactory recognition of offspring. AB - In terms of reproductive success the quality and duration of maternal care exhibited by any particular species is of paramount importance, and yet compared with the amount of research studying the control of reproductive cycles, sexual behaviour, and fertility, it has historically received considerably less attention. However, we are now beginning to understand how the brain is organised to mediate this complex behaviour and how its expression is orchestrated by different hormonal and neurochemical factors. This review summarises a series of neuroanatomical, electrophysiological, in vivo sampling and behavioural neuropharmacological experiments carried out in sheep. These have attempted to define the neural circuitry and hormonal neurotransmitter systems involved both in the control of maternal behaviour per se and in the selective olfactory recognition of lambs, which is the basis of an exclusive emotional bond between mother and offspring. PMID- 9370204 TI - Implications of immediate-early gene induction in the brain following sexual stimulation of female and male rodents. AB - Induction of immediate-early genes (IEGs), such as c-fos, has been widely used to mark the activation of brain regions following different types of sexual stimulation and behavior. A relatively common set of hormone-concentrating basal forebrain and midbrain structures in female and male rodents is activated by copulatory stimulation, in particular, stimulation of sensory nerves that innervate the penis or vagina/cervix, olfactory or pheromonal stimuli, and conditioned sexual incentives. These regions include the preoptic area, lateral septum, bed nucleus of the stria terminalis, paraventricular hypothalamus, ventromedial hypothalamus, medial amygdala, ventral premammillary nuclei, ventral tegmentum, central tegmental field, mesencephalic central gray, and peripeduncular nuclei. Regions that do not contain classic intracellular steroid receptors, such as the ventral and dorsal striatum or cortex, are also activated. IEGs have also been colocalized with cytoplasmic proteins like GnRH and oxytocin, and have been used in conjunction with retrograde tracers to reveal functional pathways associated with different sexual behaviors. Steroid hormones can also alter the ability of sexual stimulation to induce IEGs. Despite the many similarities, some differences in IEG induction between sexes have also been found. We review these findings and raise the question of what IEG induction in the brain actually means for sexual behavior, that is, whether it indicates the perception of sexual stimulation, commands for motor output, or the stimulation of a future behavioral or neuroendocrine event related to the consequences of sexual stimulation. To understand the role of a particular activated region, the behavioral or neuroendocrine effects of lesions, electrical stimulation, drug or hormone infusions, must also be known. PMID- 9370205 TI - Sex differences in function of a pheromonally stimulated pathway: role of steroids and the main olfactory system. AB - Exposure to the pheromones contained in female hamster vaginal secretions (FHVS) produces stereotypic, sex-specific behaviors in Syrian hamsters. Using Fos as a marker of neuronal stimulation we have found that (1) FHVS stimulates neurons in the posterior subdivision of the medial nucleus of the amygdala (MeP), the posterior medial subdivision of the bed nucleus of the stria terminalis (BNSTpm), and the magnocellular subdivision of the medial preoptic nucleus (MPN mag); (2) this stimulation is mediated by the main olfactory system; (3) stimulation of the MPN mag is regulated by testosterone in males; (4) stimulation of the BNSTpm and MeP is regulated by testosterone in females; and (5) FHVS does not induce Fos production in the MPN mag in females regardless of the hormonal state. These results support the hypothesis that the main olfactory system plays an important role in the regulation of pheromonally driven behaviors, identifies functional sex differences in pathways that regulate these behaviors, and emphasizes the different roles of the BNSTpm, MeP, and MPN mag in the regulation of male copulatory behavior. PMID- 9370206 TI - Female-attracting pheromone in newt cloacal glands. AB - It has been postulated that male newts emit pheromones that attract females of the same species. Female newts of the species Cynops pyrrhogaster were attracted to water in which sexually active conspecific males had been kept, but not to water in which abdominal gland-ablated males had been kept, indicating that the attracting pheromone was secreted by or through the abdominal gland of the cloaca. An attempt has been made to isolate and characterize the female attracting pheromone in the abdominal glands of male newts. Female-attracting activity was monitored using a preference test. The active substance was isolated by two steps of purification using reverse-phase high-performance liquid chromatography. Direct sequencing of the final product revealed that it is a decapeptide with the amino acid sequence Ser-Ile-Pro-Ser-Lys-Asp-Ala-Leu-Leu-Lys. Its minimum effective concentration was estimated to be between 0.1 pM and 1.0 pM. The synthetic peptide showed a female-attracting activity similar to that of the native peptide. It seems to act through the olfactory organ of female newts, because the effect of the peptide was blocked by bilateral nostril plugging with cotton balls soaked in melted vaseline. An antiserum against sodefrin was generated in a rabbit. An immunoelectron microscopic study using this antiserum revealed that sodefrin exists predominantly within secretory granules in the epithelial cells of the abdominal glands. A radioimmunoassay for sodefrin was developed in which the antiserum was used along with sodefrin which was N terminally extended with a tyrosine residue as a radioligand. The immunoassayable sodefrin content in C. pyrrhogaster males was diminished by castration and hypophysectomy. The sodefrin content was increased markedly in the castrated and hypophysectomized newts after treatment with both testosterone and prolactin. Testosterone but not prolactin increased the sodefrin content to a lesser extent. Aqueous extract of the abdominal glands of C. ensicauda showed no inhibition of binding in this assay. Moreover, C. ensicauda females were insensitive to sodefrin, although they were attracted to a water extract of abdominal glands from males of their own species. On the other hand, C. pyrrhogaster females responding to sodefrin were not attracted to the water extract of the abdominal glands from C. ensicauda males. Sequence analyses of sodefrin cDNA clones obtained from a C. ensicauda abdominal gland cDNA library revealed that the cDNA encoded a variant type of sodefrin peptide with substitutions of Leu3 and Gln8. The synthetic [Leu3, Gln8]-sodefrin attracted C. ensicauda females but not C. pyrrhogaster females. These results indicate that the female-attracting pheromone differs between these two species of genus Cynops. PMID- 9370207 TI - Role of melatonin in mediating seasonal energetic and immunologic adaptations. AB - Winter is energetically demanding and stressful; thermoregulatory demands increase when food availability usually decreases. Physiological and behavioral adaptations, including termination of breeding, have evolved among nontropical animals to cope with the energy shortages during winter. Presumably, selection for the mechanisms that permit physiological and behavioral anticipation of seasonal ambient changes have led to current seasonal breeding patterns for many populations. In addition to the well-studied seasonal cycles of mating and birth, there are also significant seasonal cycles of illness and death among field populations of mammals and birds. Energetically challenging winter conditions can directly induce death via hypothermia, starvation, or shock; surviving these demanding conditions likely puts individuals under great physiological stress. The stress of coping with energetically demanding conditions may increase adrenocortical steroid levels that could indirectly cause illness and death by compromising immune function. Individuals would enjoy a survival advantage if seasonally recurring stressors could be anticipated and countered by bolstering immune function. The primary environmental cue that permits physiological anticipation of season is daily photoperiod, a cue that is mediated by melatonin. However, other environmental factors may interact with photoperiod to affect immune function and disease processes. Immune function is compromised during the winter in field studies of birds and mammals. However, laboratory studies of seasonal changes in mammalian immunity consistently report that immune function is enhanced in short day lengths. To resolve this apparent discrepancy, we hypothesize that winter stressors present in field studies counteract short-day enhancement of immune function. Prolonged melatonin treatment mimics short days, and also enhances rodent immune function. Reproductive responsiveness to melatonin appears to affect immune function. In sum, melatonin may be part of an integrative system to coordinate reproductive, immunologic, and other physiological processes to cope successfully with energetic stressors during winter. PMID- 9370208 TI - Control of the circannual rhythm of reproduction by melatonin in the ewe. AB - Annual variations in day length are responsible for seasonal changes in reproductive activity in sheep. However, in constant photoperiodic conditions, ewes express an endogenous rhythm characterized by alternations of reproductive activity and quiescence that are not synchronized among animals. Thus, the main role of photoperiod in the natural environment appears to be the synchronization of this endogenous rhythm. Photoperiodic information is processed through a complex nervous and endocrine pathway to modulate reproductive activity. Light information perceived at the level of the retina is transformed through neural processing into an endocrine signal by the pineal gland: the nocturnal increase in melatonin release. Recent studies strongly suggest that melatonin has a hypothalamic target to modulate the reproductive neuroendocrine axis. Most LHRH perikarya are located in the preoptic area, but this region is devoid of melatonin receptors, and microimplants of melatonin placed in the preoptic area do not effect LHRH release. Thus, melatonin influences LHRH neurones indirectly and must involve interneurons. Good evidence now exists to demonstrate that a population of dopaminergic neurons with axons projecting to the median eminence is one of these interneurons. PMID- 9370209 TI - Melatonin: generation and modulation of avian circadian rhythms. AB - The pineal organ and its hormone melatonin are significant components of avian circadian pacemaking systems. In songbirds, pinealectomy results in the abolition or destabilization of overt circadian rhythms such as the rhythm of locomotor activity, feeding, or body temperature. A stable rhythmicity can be restored either by reimplanting a pineal organ, by periodic injections or infusions of melatonin, or by applying melatonin rhythmically through the drinking water. Several results suggest that the pineal melatonin rhythm acts on at least one other oscillator within the circadian pacemaking system, presumably the SCN, which in turn, feeds back to the pineal. As described by the "Neuroendocrine Loop" and "Internal Resonance" models, overall pacemaker output thus depends on the relative strengths of the oscillations in the pineal and the SCN. Investigations on migratory birds have shown that the amplitude of the 24-h plasma melatonin rhythm is reduced during the migratory seasons compared with the nonmigratory seasons. According to the models mentioned above, such a reduced melatonin amplitude should result in a reduction in the degree of self sustainment of the pacemaker as a whole. This, in turn, should facilitate adjustment to the altered Zeitgeber conditions encountered by these birds as a result of their own migratory flights. A seasonal reduction in melatonin amplitude also occurs in some high-latitude birds during midsummer and midwinter. Under such conditions a less self-sustained circadian pacemaker may enhance entrainability to weak zeitgeber conditions. These examples suggest that the properties of the circadian system may be adjusted to match the changing requirements for synchronization, and that this is achieved by altering the melatonin amplitude. PMID- 9370210 TI - The GnRH system of seasonal breeders: anatomy and plasticity. AB - Seasonal breeders, such as sheep and hamsters, by virtue of their annual cycles of reproduction, represent valuable models for the study of plasticity in the adult mammalian neuroendocrine brain. A major factor responsible for the occurrence of seasonal reproductive transitions is a striking change in the responsiveness of gonadotropin-releasing hormone (GnRH) neurons to the inhibitory effects of gonadal steroids. However, the neural circuitry mediating these seasonal changes is still relatively unexplored. In this article, we review recent findings that have begun to define that circuitry and its plasticity in a well-studied seasonal breeder, the ewe. Tract tracing studies and immunocytochemical analyses using Fos and FRAs as markers of activation point to a subset of neuroendocrine GnRH neurons in the MBH as potential mediators of pulsatile GnRH secretion. Because the vast majority of GnRH neurons lack estrogen receptors, seasonal changes in responsiveness to estradiol are most probably conveyed by afferents. Two possible mediators of this influence are dopaminergic cells in the A14/A15 cell groups of the hypothalamus, and estrogen receptor containing cells in the arcuate nucleus that project to the median eminence. The importance of GnRH afferents in the regulation of season breeding is underscored by observations of seasonal changes in the density of synaptic inputs onto GnRH neurons. Thyroid hormones may participate in this remodeling, because they are important in seasonal reproduction, influence the morphology of other brain systems, and thyroid hormone receptors are expressed within GnRH neurons. Finally, in the hamster, neonatal hypothyroidism affects the number of caudally placed GnRH neurons in the adult brain, suggesting that thyroid hormones may influence development of the GnRH system as well as its reproductive functions in the adult brain. PMID- 9370212 TI - Astrocyte-neuron interactions in vitro: role of growth factors and steroids on LHRH dynamics. AB - The data here reviewed, obtained with in vitro models, indicate that growth factors and steroids play a significant role in astrocyte-neuron interactions. Different designs have been adopted: (1) GT1-1 cells (a cell line derived from a mouse hypothalamic LHRH-producing tumor) were cocultured with type 1 rat astrocytes; and (2) GT1-1 cells were exposed to the conditioned medium (CM) in which type 1 rat astrocytes had been grown for 24 h. LHRH release and mRNA LHRH levels were measured respectively in the medium and in cell homogenates, at different time intervals (LHRH release, by RIA; LHRH mRNA by Northern blot analysis). The data obtained show that type 1 astrocytes secrete in the medium TGFbeta, which is able to modulate the release and the gene expression of LHRH in GT1-1 cells; and that one or more LHRH-degrading enzymes is/are present in the conditioned medium of type 1 astrocytes. A second part of the experiments have indicated that type 1 astrocytes are also able to affect, in different directions, the metabolism of testosterone and progesterone into their 5alpha reduced metabolites occurring in the GT1-1 cells. In particular, it has been observed that the conversion of testosterone into DHT is decreased by the coculture with type 1 astrocytes, while the conversion of progesterone into DHP is increased by the same coculture conditions. Moreover, type 1 astrocytes are sensitive to steroid hormones, and in particular to the 5alpha-reduced metabolites of progesterone; this has been shown by analyzing the effects exerted by different steroids on the gene expression of the typical astrocyte marker GFAP. PMID- 9370211 TI - Behavioral regulation of gonadotropin-releasing hormone production. AB - In vertebrates reproductive readiness requires coordination between the sexes. Behavioral interactions with potential mates can initiate the neuroendocrine events that are required for successful copulation, ovulation, and fertilization. Regardless of the efferent pathway used, their targets are the neurons that produce and secrete gonadotropin-releasing hormone (GnRH). Several excellent animal models are currently under use to study the relationship between behavior and GnRH. In the musk shrew (Suncus murinus) starting 15 h after mating, prior to ovulation, GnRH-ir cell numbers are elevated along with GnRH content in brain and estradiol in plasma. Immunoreactive GnRH cell numbers also change in brains of female musk shrews sacrificed during, and directly after, brief interactions with males. These rapid changes in GnRH-ir cells are not correlated with measurable increases in GnRH content or elevations in plasma concentrations of estradiol. To determine which aspect(s) of the behavioral interaction is salient for the change in GnRH-ir, studies have been conducted in which interactions with males and their sensory cues were restricted during a 1-h interaction. In this study, behavioral interactions with an awake male behind a screen barrier resulted in a decrease in the numbers of GnRH-ir cells in the forebrain. Further studies with this animal model will help determine how behavioral inputs stimulate processing and release of GnRH. PMID- 9370213 TI - Neuroendocrine regulation of GnRH and behavior during aging in birds. AB - Avian species exhibit a great variety of life-long patterns in reproduction. Japanese quail are relatively short lived and undergo an age-related loss of reproductive function, making this species an excellent model for the study of the basic biology of aging. Because individuals age at variable rates, sexual behavior has provided a useful index to assess reproductive status of individuals of the same chronological age. Further, exogenous testosterone restores sexual behavior in reproductively senescent male quail, thereby providing evidence for a continued ability of the system to respond. In addition, we have been studying hypothalamic neuroendocrine systems that regulate the endocrine as well as behavioral components of reproduction. Overall, our findings point to the hypothalamic neuroendocrine systems as the site of initial age-related alterations that contribute to the reproductive deterioration. Specifically, we studied adrenergic, opioid peptide, vasotocin, and aromatase systems to understand their relationship to the cGnRH-I system and their potential role in the deterioration of the cGnRH-I system during aging. Our findings provide evidence for qualitative and quantitative alterations in the aromatase enzyme system, which can be partially restored with exogenous testosterone. In addition, other neuronal systems, including the vasotocin system, decline with the loss of gonadal steroids and are restimulated with exogenous testosterone. We will synthesize the data relative to these neuroendocrine systems with attention to the effects of gonadal steroids on these systems during aging. PMID- 9370214 TI - Gonadotropin-releasing hormone containing neurons and olfactory fibers during development: from lamprey to mammals. AB - Gonadotropin releasing-hormone (GnRH) regulates the hypothalamo-pituitary-gonadal axis in all vertebrates. The vast majority of GnRH neurons are thought to be derived from progenitor cells in medial olfactory placodes. Several antibodies and lectins that recognize cell surface carbohydrates have been useful for delineating the migratory pathway from the olfactory placodes and vomeronasal organ, through the nasal compartment, and across the cribriform plate into the brain. In rats, alpha-galactosyl-linked glycoconjugates (immunoreactive with the CC2 monoclonal antibody) are expressed on fibers along the GnRH migration pathway and approximately 10% of the GnRH neuronal population. In lamprey, the alpha galactosyl binding lectin, Grifonia simplicifolia-I (GS-1), identifies cells and fibers of the developing olfactory system. In contrast to the CC2 immunoreactive GnRH neurons in rats, the GS-1 does not label a subpopulation of presumptive GnRH neurons in lamprey. Results from these and other experiments suggest that GnRH neurons in developing lamprey do not originate within the olfactory placode, but rather within proliferative zones of the diencephalon. However, the overlap of olfactory- and GnRH-containing fibers from prolarval stages to metamorphosis, suggest that olfactory stimuli may play a major role in the regulation of GnRH secretion in lamprey throughout life. By contrast, olfactory fibers are directly relevant to the migration of GnRH neurons from the olfactory placodes in mammalian species. Primary interactions between olfactory fibers and GnRH neurons are likely transient in mammals, and so in later life olfactory modulation of GnRH secretion is likely to be indirect. PMID- 9370215 TI - Excitatory neurotransmission and sexual differentiation of the brain. AB - During normal development there is a perinatal sensitive period during which the male brain is exposed to high levels of gonadal steroids, resulting in permanent differentiation of neural substrates. The cellular mechanisms mediating hormonally induced sexual differentiation remain largely unknown. In the adult brain, steroids exert profound influences on the amino acid transmitters, GABA, and glutamate. We have found steroid regulation of amino acid neurotransmission during the perinatal sensitive period and propose this may be functionally related to sexual differentiation of the brain. Specifically, the mRNA coding for the rate-limiting enzyme in GABA synthesis, glutamic acid decarboxylase (GAD), is up to twice as high in some steroid-concentrating regions of the neonatal male brain compared to females, including the arcuate nucleus, dorsomedial nucleus, and the CA1 region of hippocampus. Sex differences in GABA tissue concentrations positively correlate with GAD mRNA differences in several brain regions. There are also sex differences in protein levels of GABA(A) receptor subunits. In parallel with these findings are significantly higher levels of binding to the non-NMDA glutamate receptor in steroid-concentrating regions of male brain. Given that GABA is an inhibitory transmitter and glutamate is an excitatory amino acid, these results initially appear paradoxical. However, in contrast to its inhibitory action in the adult brain, early in development GABA is actually excitatory and acts in a manner analogous to glutamate. Therefore, the combination of increased excitatory GABAergic and glutamatergic activity should result in substantially higher levels of neuronal excitation in the male brain. We speculate that an increased level of neuronal excitation is a potential mechanism mediating the permanent masculinization of the brain. PMID- 9370216 TI - Organizational actions of sex hormones on sexual partner preference. AB - Sexual dimorphism in copulatory behavior results from organizational actions of sex steroids (permanent effects of sex steroids occurring during early development). Reproductive success depends not only on copulatory behavior, but also on mate choice, which is often sexually dimorphic as well. The clearest example is sexual partner preference: the preference of males for female sexual partners and females for males. Are organizational hormone actions responsible for sexual differentiation of sexual partner preference? The zebra finch (Taeniopygia guttata) is a potentially valuable species for addressing this question, because the birds form life-long socially monogamous pair bonds. In one experiment, both early estrogen treatment (injection with estradiol benzoate-EB for the first 2 weeks posthatch) and unisex housing during juvenile development independently resulted in a preference for females over males in two-choice tests, and only females that experienced both EB treatment and unisex living were more likely than controls to pair with other females in colony tests. In a second experiment, females injected with an estrogen synthesis inhibitor for the first week posthatch preferred to spend time near females instead of males in two choice tests, unlike control females. These experiments suggest that sexual partner preference may result from organizational hormone actions in this pair bonding species. Possible neural mechanisms or sites that could underly hormonal organization of sexual partner preference in birds and mammals include the anterior hypothalamic/preoptic area, the corticomedial amygdala, and its avian homologue nucleus taeniae of the archistriatum, the septum, and peripheral sensory processes. PMID- 9370217 TI - Experimental analysis of sexual differentiation of the zebra finch brain. AB - Classical theories of sexual differentiation of brain and behavior hold that sex differences in the brain arise because of the action of gonadal steroid hormones. In mammals, testosterone secretion by the testes stimulates a masculine pattern of neural differentiation, whereas feminine patterns of development occur in the absence of testicular secretions. In some bird species, estrogen secreted by the ovary is thought to trigger feminine patterns of neural development, whereas masculine development occurs in the absence of ovaries. Sexual differentiation of the neural circuit for song in zebra finches is not easily explained by these theories. Although female zebra finches can be masculinized by treatments with estrogen, it has proven difficult to prevent masculine neural development in genetic males by treating them with inhibitors of estrogen synthesis. Moreover, when genetic female embryos are treated with inhibitors of estrogen synthesis, they develop significant amounts of testicular tissue that causes little or no masculinization of the song system. Thus, testicular secretions alone appear to be insufficient to cause masculine neural differentiation, and other factors need to be invoked. These factors may include ovarian secretions that inhibit masculine development, or direct genetic (nonhormonal) effects on neural differentiation. PMID- 9370218 TI - Distribution and dynamics in the expression of androgen and estrogen receptors in vocal control systems of songbirds. AB - Developmental and seasonal changes in the production of androgens and estrogens seem to control sex-specific differentiation and seasonal changes in sexual behaviors such as singing of songbirds. These steroids affect the brain by binding to intracellular located receptors. Here we analyze whether the expression of androgen receptors (AR) and estrogen receptors (ER) is a limiting factor for differentiation of the vocal pattern and the vocal control system of zebra finches and canaries. AR and ER are localised in the brain using in situ hybridizations with cRNA probes of the AR and ER of the zebra finch. AR are widely expressed in the vocal control system and allow androgen-dependent alterations of the development and function of most vocal control areas. The expression of AR in some vocal control areas such as NIF, DLM, and AVT differs between individuals. This individual variability suggests genetic differences or transient steroid-independent expression of AR. ER are found only in the HVC and thus restrict estrogen-dependent developmental and functional changes of the singing to the HVC area. AR- and ER-mRNA expression per cell in the HVC of adult canaries undergoes seasonal changes so that ER are higher expressed from fall to the early breeding season. During ontogeny, ER start to occur in the zebra finch HVC at posthatching day 15 and in the canary HVC at posthatching day 30. As the HVC is already sexual dimorphic in size at these times, HVC-based estrogen-ER dependent mechanisms seem not to be important for the initial sexual dimorphic development of the HVC. PMID- 9370219 TI - SK-ER3 neuroblastoma cells as a model for the study of estrogen influence on neural cells. AB - The neuroblastoma SK-ER3 cell line obtained by stable transfection of the human SK-N-BE cell line is proposed as a model for the study of estrogen receptor activity in cells of neural origin. In the SK-ER3 cell line the estrogen receptor, once activated, initiates a differentiation program leading to growth arrest, morphological changes, and acquisition of the dopaminergic phenotype. In the absence of estrogens, this program can be triggered by IGF-I, which can activate the unliganded estrogen receptor via the ras-pathway. It is proposed that this model system might recapitulate the events occurring in vivo during the differentiation of the nervous system and that IGF-I may play an important role in the activation of estrogen receptor at the very early stage of brain development affecting the differentiation of a number of hypothalamic and extrahypothalamic brain regions. PMID- 9370220 TI - Role of astroglia and insulin-like growth factor-I in gonadal hormone-dependent synaptic plasticity. AB - Gonadal hormones exert a critical influence over the architecture of specific brain areas affecting the formation of neuronal contacts. Cellular mechanisms mediating gonadal hormone actions on synapses have been studied extensively in the rat arcuate nucleus, a hypothalamic center involved in the feed-back regulation of gonadotropins. Gonadal steroids exert organizational and activational effects on arcuate nucleus synaptic connectivity. Perinatal testosterone induces a sexual dimorphic pattern of synaptic contacts. Furthermore, during the preovulatory and ovulatory phases of the estrous cycle there is a transient disconnection of inhibitory synaptic inputs to the somas of arcuate neurons. This synaptic remodeling is induced by estradiol, blocked by progesterone, and begins with the onset of puberty in females. Astroglia appear to play a significant role in the organizational and the activational hormone effects on neuronal connectivity by regulating the amount of neuronal membrane available for the formation of synaptic contacts and by releasing soluble factors, such as insulin-like growth factor I (IGF-I), which promote the differentiation of neural processes. Recent evidence indicates that gonadal steroids and IGF-I may interact in their trophic effects on the neuroendocrine hypothalamus. Estradiol and IGF-I promote the survival and morphological differentiation of rat hypothalamic neurons in primary cultures. The effect of estradiol depends on IGF-I, while the effects of both estradiol and IGF-I depend on estrogen receptors. Furthermore, estrogen activation of astroglia in hypothalamic tissue fragments depends on IGF-I receptors. These findings indicate that IGF-I may mediate some of the developmental and activational effects of gonadal steroids on the brain and suggest that IGF-I may activate the estrogen receptor to induce its neurotrophic effects on hypothalamic cells. In addition, IGF-I levels in the neuroendocrine hypothalamus are regulated by gonadal steroids. IGF-I levels in tanycytes, a specific astroglia cell type present in the arcuate nucleus and median eminence, increase at puberty, are affected by neonatal androgen levels, show sex differences, and fluctuate in accordance to the natural variations in plasma levels of ovarian steroids that are associated with the estrous cycle. These changes appear to be mediated by hormonal regulation of IGF-I uptake from blood or cerebrospinal fluid by tanycytes. These results suggest that tanycytes may be involved in the regulation of neuroendocrine events in adult rats by regulating the availability of IGF-I to hypothalamic neurons. In summary, IGF-I and different forms of neuron-astroglia communication are involved in the effects of estradiol on synaptic plasticity in the hypothalamic arcuate nucleus. PMID- 9370221 TI - Expression and plasticity of NO synthase in the neuroendocrine system. AB - The expression of the nitric oxide (NO)-synthase enzyme (NOS) was analyzed in several hypothalamic nuclei and in the pituitary gland using in situ hybridization and immunohistochemistry. The effects of physiological and experimental stimuli on the expression of NOS was also investigated. Moreover, the role of NO in the secretion of anterior pituitary hormone luteinizing hormone (LH) was studied using primary culture of pituitary cells. The findings indicate that the expression of neuronal NOS is hormonally regulated and suggest that NO plays a role in hormone secretion. PMID- 9370222 TI - Hormonally induced neuronal plasticity in the adult motoneurons. AB - Sex steroids are known to play a crucial role in reproductive neuroendocrine functions in adulthood. A number of neurons in the neuroendocrine brain contain sex steroid receptors, and are thought to be a key element of functional neural circuits that are regulated by sex steroids. Motoneurons in the spinal nucleus of the bulbocavernosus in adult male rodents are one of the androgen-sensitive neural substrates. In the spinal nucleus of the bulbocavernosus, castration of adult male rats results in a significant decrease in the somatic size and dendritic length of the motoneurons, and in the number and size of chemical and electrical (gap junction) synapses onto these motoneurons. Androgen treatment of castrates reverses these changes. Furthermore, androgen has been reported to be involved in regulation of androgen receptor expression and gene expression of structural proteins such as beta-actin, beta-tubulin and gap junction channels in these motoneurons. The findings suggest that androgen induces morphological and molecular changes in the motoneurons that reflect their neural functions, and may provide evidence for the mechanisms of hormonally induced neuronal plasticity in the motoneurons in adulthood. PMID- 9370223 TI - Thyroid hormone-induced plasticity in the adult rat brain. AB - It is well known that thyroid hormone plays a crucial role in the development and maturation of the nervous system. However, little is known about the role of thyroid hormone in the adult brain. In this short review we have dwelt on this point, with regard to the role of thyroid hormone on neuropeptide gene expression regulation in the paraventricular nucleus of the hypothalamus and in extrahypothalamic brain areas, on neurotrophin and neurotrophin receptor expression in the hippocampus and basal forebrain in basal conditions, and after neurotoxic challenges. Effects of hypothyroidism are discussed in view of a possible role of thyroid status in brain aging quality. PMID- 9370224 TI - State-specific prevalence of cigarette smoking among adults, and children's and adolescents' exposure to environmental tobacco smoke -- United States, 1996. AB - In 1996, the prevalence of cigarette smoking was added to the list of nationally notifiable health conditions reported by states to CDC. The addition of a health related behavior to the list of diseases and illnesses reflected the recognized role of tobacco use as the leading preventable cause of death in the United States. This report summarizes the 1996 prevalence of current smoking among adults in 49 states and the District of Columbia and presents state-specific estimates of environmental tobacco smoke (ETS) exposure for children and adolescents residing in homes where adults smoke. The findings indicate that state-specific smoking prevalence among adults varied twofold and that approximately 15 million children and adolescents were exposed to ETS in their home. PMID- 9370225 TI - Filter ventilation levels in selected U.S. cigarettes, 1997. AB - Cigarette brands that deliver < or = 15 mg of tar in official smoking-machine tests accounted for 72.7% of total cigarette sales in 1995. Many of these brands use ventilated filters-a system with small perforations around the filter that are designed to draw in additional air during smoking. In brands with ventilated filters, air introduced through the vents dilutes the amounts of tar, nicotine, carbon monoxide (CO), and other hazardous constituents of cigarette smoke. This report summarizes results of tests conducted by researchers at The Pennsylvania State University during July 1997 to measure the percentage of air drawn through the filter vents of 32 brands of U.S. cigarettes that have tar yields rated by the Federal Trade Commission (FTC) as ranging from 1 mg-18 mg; the report also examines the correlation between the degree of filter ventilation and tar yield. The findings indicate that 30 (94%) of 32 brands tested were ventilated and that percentage filter ventilation varied inversely with standard tar, nicotine, and CO yields. PMID- 9370226 TI - Medical-care expenditures attributable to cigarette smoking during pregnancy -- United States, 1995. AB - An estimated 26% of women of reproductive age (i.e., 18-44 years) smoked in 1993, and approximately 19%-27% of women smoke during pregnancy. Smoking during pregnancy is causally associated with an annual estimated 32,000-61,000 low birthweight infants and 14,000-26,000 admissions to neonatal intensive-care units. The estimated smoking-attributable direct medical-care costs for chronic conditions in 1993 were $50.0 billion; however, this estimate omitted the direct medical costs of tobacco exposure for infants and children and most of these costs for pregnant women. To derive 1995 estimates of the smoking-attributable costs for direct medical expenditures (i.e., inpatient, physician, hospital outpatient, and emergency department costs) related to pregnancy outcomes, the University of California at Berkeley and CDC analyzed data from the 1987 National Medical Expenditures Survey (NMES-2). This report summarizes the findings, which indicate substantial smoking-attributable direct medical expenditures for pregnant women and newborns. PMID- 9370227 TI - Molecular cytogenetics of brain tumors. AB - Molecular cytogenetics includes a spectrum of methodologies that use molecular reagents to better define chromosomal alterations in normal and neoplastic cells. Brain tumors are a group of neoplasms for which there is a wealth of cytogenetic and molecular genetic information, and some of the newer techniques have extended the types of samples from which genetic information which can be obtained to biopsies and even paraffin-embedded sections. Fluorescence in situ hybridization on interphase nuclei has been used to confirm gains of chromosome 7, loss of chromosome 10, 9p deletion and gene amplification in malignant gliomas, and to visualize isochromosome 17q in medulloblastomas. Comparative genomic hybridization uses genomic DNA to determine gains and losses of chromosomes and chromosomal regions. This approach is particularly useful for identifying gene amplification. For cases in which chromosomal spreads are obtained, chromosomal painting is helpful in determining the origin of chromosomal segments. Several methods are now available in which each of the 22 autosomes and the sex chromosome can be identified by unique colors, termed Spectral karyotyping and multiplex-FISH. These molecular cytogenetic techniques are important clinical and experimental tools that have provided new insight into the genetic alterations of brain tumors. PMID- 9370228 TI - Alteration of E-cadherin and alpha N-catenin immunoreactivity in the mouse spinal cord following peripheral axotomy. AB - We examined the effects of peripheral axotomy on the immunoreactivity of E cadherin and cadherin-associated protein alpha N-catenin in the spinal cord. E cadherin is known to be exclusively expressed in lamina II of Rexed in the spinal cord dorsal horn. This expression disappeared by day 7 after axotomy and reappeared following nerve ligature (partial axonal regeneration model) on day 63. In contrast, it remained undetectable following nerve clipping (complete degeneration model). Alpha N-catenin was diffusely stained in the gray matter, and the immunoreactivity was specifically intense in the central canal and superficial dorsal horn. The expression of alpha N-catenin in the superficial dorsal horn was similarly reduced by day 7 after axotomy, but recovered by day 63 after nerve ligature. In contrast, it remained at the reduced level after nerve clipping. The alteration of alpha N-catenin immunoreactivity showed a similar pattern consistent with that of E-cadherin. Administration of nerve growth factor (NGF) rescued the immunoreactivity of substance P, which is known to disappear after peripheral axotomy, but not influence that of both E-cadherin or alpha N catenin. These results clearly showed that peripheral axotomy simultaneously alters the immunoreactivity of E-cadherin and alpha N-catenin in the spinal cord, suggesting a correlation in the expression of both E-cadherin and alpha N-catenin in vivo. E-cadherin-alpha N-catenin complex might be crucial for plasticity of the spinal cord dorsal horn after peripheral axotomy. PMID- 9370229 TI - Identification of post-mitotic oligodendrocytes incapable of remyelination within the demyelinated adult spinal cord. AB - In order to investigate the remyelinating potential of mature oligodendrocytes in vivo, we have developed a model of demyelination in the adult rat spinal cord in which some oligodendrocytes survive demyelination. A single intraspinal injection of complement proteins plus antibodies to galactocerebroside (the major myelin sphingolipid) resulted in demyelination followed by oligodendrocyte remyelination. Remyelination was absent when the spinal cord was exposed to 40 Grays of x-irradiation prior to demyelination, a procedure that kills dividing cells. Quantitative Rip immunohistochemical analysis revealed a similar density of surviving oligodendrocytes in x-irradiated and nonirradiated lesions 3 days after demyelination. Rip and bromodeoxyuridine double immunohistochemical analysis of demyelinated lesions indicated that Rip+ oligodendrocytes did not divide as an acute response to demyelination. Oligodendrocytes were also identified by Rip immunostaining and electron microscopy at late time points (3 weeks) within x-irradiated areas of demyelination. These oligodendrocytes extended processes that engaged axons, and on occasion formed myelin membranes, but did not lay down new myelin sheaths. These studies demonstrate that (a) oligodendrocytes that survive within a region of demyelination are not induced to divide in the presence of demyelinated axons, and (b) fully-differentiated oligodendrocytes are therefore postmitotic and do not contribute to remyelination in the adult CNS. PMID- 9370230 TI - Comparison of two quantitative methods for the evaluation of neuronal number in the frontal cortex in Alzheimer disease. AB - How to assess the substantial neuronal loss in a neurodegenerative disease such as Alzheimer disease is still being debated. Recently, stereological procedures have been proposed that claim improved accuracy and statistical power, but the results of some of these investigations have been controversial. In this study we compared and correlated the cell density results calculated per unit of volume obtained by a stereological technique, the "selector," with the cell counts per unit area obtained by computer-aided image analysis morphometry, in the same sections of midfrontal cortex in Alzheimer disease and control cases. The "selector" revealed a significant decrease in neuronal density that correlated well with a similar fall in large neuronal counts per unit area, as estimated by image analysis morphometry. These results indicate that stereological techniques and image analysis morphometry are complementary methods in reliably assessing cellular populations in neurodegenerative disorders. PMID- 9370231 TI - Pathology of the central nervous system in Chester-Erdheim disease: report of three cases. AB - Chester-Erdheim disease is a rare form of non-Langerhans cell histiocytosis consisting of disseminated xanthogranulomatous infiltration and fibrosis that primarily involves the bones, visceral organs and systemic fatty spaces. Involvement of the central nervous system is variable, and neuropathological features have seldom been documented. We report the neuropathological findings in 3 autopsy cases. One patient had radiological and pathological bone changes characteristic of Chester-Erdheim disease. Neuropathology revealed multiple characteristic xanthogranulomas disseminated in the cerebral hemispheres, hypothalamus, cerebellum, and brainstem. The second patient presented first with cutaneous lesions characteristic of Langerhans cell histiocytosis. She subsequently developed bone abnormalities suggestive of Chester-Erdheim disease, which was confirmed by autopsy, raising the possibility of a common spectrum of histiocytosis including both diseases. Gross examination of the brain was normal, however, microscopy showed infiltration of the brain by characteristic non Langerhans cell xanthogranulomas. The third patient presented with systemic features characteristic of Chester-Erdheim disease. Neurological signs included gait disturbance, seizures and confusion. Examination of the brain did not show any histiocytic infiltration, but did show changes suggestive of Hallervorden Spatz syndrome. Association of Chester-Erdheim disease and Hallervorden-Spatz syndrome has not been previously reported. The relationship between both conditions is unclear. PMID- 9370232 TI - Membranous ultrastructure of human arachnoid cells. AB - The ultrastructure of arachnoid cell membranes was investigated by conventional transmission EM and by freeze-fracture techniques in human arachnoid granulations. Arachnoid cells showed widespread membrane specialization in the granulations including the formation of desmosomes, gap junctions, tight junctions, intermediate junctions, hemidesmosome-like structures, and micropinocytotic vesicles. However, the extent of the specialization varied from portion to portion; this was clearly shown on freeze-fracture replicas. Numerous extracellular cisterns were separated by cytoplasmic bodies or slender processes, joined by these junctional complexes. Uncoated and coated vesicles were abundant along the surface of extracellular cisterns representing the pathway of CSF. Complexes of branching tight junctions were comprised of 1-50 particle strands, which formed elaborate meshworks accompanied by numerous gap junctions and desmosomes. Micropinocytotic vesicles were often concentrated in the arachnoid cell cluster up to 40 per microm2, which is equivalent to the concentration in brain capillary endothelial cells. The results of this study clearly suggest that arachnoid cells in arachnoid granulations are not only tightly adherent to form a firm structure for the passage of CSF, but that the arachnoid cells lining the CSF pathway show intense cell-cell communication and pinocytotic activity. This high transcellular activity probably reflects active transports or secretion of certain molecules by arachnoid cells. PMID- 9370233 TI - Apolipoprotein E accumulates with the progression of A beta deposition in transgenic mice. AB - To study the role of apolipoprotein E (apoE) in vivo in deposits of amyloid beta protein (A beta), a major component of senile plaque amyloid in the brain of patients with Alzheimer disease, the transgenic mice were examined by apoE immunostaining. The mice were systemically overexpressing signal peptide and 99 amino acid residues of the carboxy-terminal fragment of human amyloid beta protein precursor (betaAPP) under control of the powerful cytomegalovirus enhancer/chicken beta-actin promotor. A beta deposits appeared at 4 months and increased with aging in the acinar cells of the transgenic pancreas. Similarly, apoE deposits appeared in the pancreatic acinar cells at 4 months old. The number and size of apoE deposits increased with aging and correlated with the progression of A beta deposits. Interstitial macrophages labeled by apoE immunostaining appeared at 8 months after birth and their number increased with aging. On serial section of the pancreata of 24-month-old mice, approximately 70% of A beta deposits were labeled with the apoE antiserum. ApoE was detected in the highly insoluble formic acid fraction of the transgenic pancreas by an immunoblot study. The Northern blot study revealed no increase in synthesis of endogenous apoE mRNA. These findings indicate that apoE is closely related to progression of A beta deposits with aging and suggest that A beta deposition in the transgenic pancreas is similar to that in the senile plaque of Alzheimer brains. Therefore, our experimental system using transgenic mice will provide a useful tool to analyze the molecular mechanism of A beta deposition in association with apoE in vivo. PMID- 9370234 TI - p53 mutations versus EGF receptor expression in giant cell glioblastomas. AB - Recent studies have shown that there are distinct genetic pathways leading to the most malignant astrocytic neoplasm, the glioblastoma. Primary (de novo) glioblastomas are characterized by amplification/overexpression of the EGF receptor (EGFR) and, less frequently, of the MDM2 gene. Another pathway, operative in the progression of low-grade or anaplastic astrocytomas to secondary glioblastomas, is characterized by the frequent occurrence of p53 mutations. In this study, we assessed p53 mutations and EGFR expression in the giant cell glioblastoma. This rare variant is characterized by unusually large, multinucleated giant cells, but tends to be more confined and has been reported to carry a somewhat more favorable prognosis. We analyzed biopsies from 16 patients (mean age at clinical manifestation, 40 years). DNA sequencing revealed that 12 of 16 (75%) giant cell glioblastomas contained a p53 mutation. In 7 patients with two or more surgical interventions, the p53 mutation was already detected in the first biopsy. Focal EGFR overexpression, including multinucleated giant cells, was observed immunohistochemically in 9 of 16 (56%) tumors. However, most tumor areas lacked immunoreactivity, indicating that EGFR overexpression does not play a significant role in the evolution of this glioblastoma variant. These results suggest that giant cell glioblastomas develop de novo with a short preoperative history (mean, 47 +/- 40 days), but contain genetic alterations similar to those observed in secondary glioblastomas. PMID- 9370236 TI - Decreased kainate receptor binding in the arcuate nucleus of the sudden infant death syndrome. AB - The human arcuate nucleus is postulated to be homologous to ventral medullary surface cells in animals that participate in ventilatory and blood pressure responses to hypercarbia and asphyxia. Recently, we reported a significant decrease in muscarinic cholinergic receptor binding in the arcuate nucleus in victims of the sudden infant death syndrome compared with control patients that died of acute causes. To test the specificity of the deficit to muscarinic cholinergic binding, we examined kainate binding in the arcuate nucleus in the same database. We assessed 3H-kainate binding to kainate receptors with tissue receptor autoradiography in 17 brainstem nuclei. Analysis of covariance was used to examine differences in binding by diagnosis, adjusted for postconceptional age (the covariate). Cases were classified as SIDS, 47; acute control, 15; and chronic group with oxygenation disorder, 17. (Acute controls are infants who died suddenly and unexpectedly and in whom a complete autopsy established a cause of death). The arcuate nucleus was the only region in which there was a significant difference in the age-adjusted mean kainate binding between the SIDS group (37+/ 2 fmol/mg tissue) and both the acute controls (77+/-4 fmol/mg tissue) (p < 0.0001) and the chronic group (69+/-4 fmol/mg tissue) (p < 0.0001). There was a positive correlation between the density of muscarinic cholinergic and kainate binding in the SIDS cases only (R = 0.460; p = 0.003). The neurotransmitter deficit in the arcuate nucleus in SIDS victims involves more than one receptor type relevant to carbon dioxide and blood pressure responses at the ventral medullary surface. PMID- 9370235 TI - Putative control of angiogenesis in hemangioblastomas by the von Hippel-Lindau tumor suppressor gene. AB - The hypoxia-inducible endothelial cell-specific mitogen vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) is expressed in low amounts in adult human brain, but is highly upregulated in the perinecrotic palisading cells of glioblastomas. We observed high VEGF expression in cerebellar hemangioblastomas, which are highly vascular, nonnecrotic and presumably nonhypoxic tumors, and hypothesized that a mechanism other than hypoxia leads to VEGF upregulation. Because hemangioblastomas develop in patients with von Hippel Lindau disease, and mutations of the von Hippel-Lindau tumor suppressor (VHL) gene have also been reported in sporadic hemangioblastomas, we investigated VHL expression in normal cerebellum and in hemangioblastomas and tested the hypothesis that mutations in the VHL gene lead to upregulation of VEGE We observed constitutive expression of VHL mRNA, but downregulation of VEGF mRNA in the postnatal cerebellum. In the adult cerebellum, VHL is predominantly expressed in neuronal cells. In hemangioblastomas, VHL expression appears to be restricted to stromal cells, suggesting that the neoplastic component is the stromal cell. VHL-deficient renal cell carcinoma cells (786-0) produced significantly higher levels of VEGF mRNA and protein compared with 786-0/ wt10 cells, which were stably transfected with the wild-type VHL gene. Our observations suggest that VHL mutations affect stromal cells in hemangioblastomas and that VEGF is upregulated in stromal cells as a consequence of mutations in the VHL gene. PMID- 9370237 TI - Axonal damage revealed by accumulation of beta-APP in HIV-positive individuals without AIDS. AB - The presence of neuropsychological disturbances in HIV-positive, pre-symptomatic individuals is a controversial issue. Neuroimaging studies have not shown brain atrophy or hyperintensity in the white matter, whereas proton magnetic resonance spectroscopy has revealed some abnormality of cerebral biochemistry. Using an antibody to beta-amyloid precursor protein (beta-APP), we previously demonstrated frequent and widespread axonal changes in the brains of AIDS patients. In this study, we extended the use of beta-APP to asymptomatic patients in order to establish a possible morphological correlation with neuropsychological disorders. Brain samples from 29 patients were examined. Results showed bundles of beta-APP positive axons in 8/29 cases (27%). The changes, seen in both superficial and deep white matter, were either focal or diffuse, could not be visualized by silver or ubiquitin stains, and did not coexist with any change in distribution or morphology of astrocytes and microglial cells. We conclude that in HIV positive asymptomatic individuals, axonal changes: (a) may be related to the state of immune activation with consequent presence of toxic substances, including cytokines, observed in these patients; (b) may represent mild changes that could undergo repair, unless other pathological events, such as the supervening of the AIDS stage and the specific encephalitis, make them permanent. PMID- 9370239 TI - Liquid-liquid immiscibility in lipid monolayers. AB - Some binary lipid mixtures form coexisting liquid phases when spread at the air/water interface. This work describes the pressure-composition phase diagrams of binary mixtures of four unsaturated phosphatidylcholines with dihydrocholesterol. These four binary mixtures have critical compositions of approximately fifty mole percent, and average critical exponents of 0.25 +/- 0.07. The data can also be approximated by a regular solution thermodynamic model, yielding parameters for the non-ideality of these mixtures. PMID- 9370238 TI - Hypertonicity enhances expression of functional Na+/K+/2Cl- cotransporters in Ehrlich ascites tumour cells. AB - Ehrlich cells exposed to a hypertonic medium for five hours respond by an increased expression of Na+/K+/2Cl- cotransport proteins as estimated from immunoprecipitations using polyclonal anti-cotransporter antibodies. The 3.4-fold increase in cotransport expression is followed by a concomitant 2.6-fold increase in the maximal bumetanide-sensitive K+ influx during regulatory volume increase, indicating a 2.6-fold increase in the number of functional cotransporters in the plasma membrane. PMID- 9370240 TI - Alpha- and beta-subunits of a V-type membrane ATPase in a hyperthermophilic sulfur-dependent archaeum, Thermococcus sp. KI. AB - The genes encoding alpha- and beta-subunits of a V-type ATPase in a sulfur dependent hyperthermophilic archaeum, Thermococcus sp. KI, were cloned and sequenced. The deduced amino acid sequences were approximately 60, 50 and 25% identical to those of other archaeal, eukaryotic V-type and E. coli F-type ATPase, respectively. Phylogenetic analysis revealed that Thermococcus ATPase was closely related to that of Thermus, and those of Methanosarcina and Halobacterium. PMID- 9370241 TI - A new member of the transmembrane 4 superfamily (TM4SF) of proteins from schistosomes, expressed by larval and adult Schistosoma japonicum. AB - The transmembrane 4 superfamily (TM4SF) comprises an assemblage of surface antigens from mammalian cells and from the human blood flukes. Member proteins of the TM4SF are characterized by the presence of four hydrophobic domains, which are presumed to be membrane-spanning, and specific conserved motifs. The Sm23 group of TM4SF, which includes Sm23, Sj23, and Sh23 from blood flukes, shows potential as immunodiagnostic and vaccine target antigens for use in controlling human schistosomiasis. Here we describe a cDNA from miracidia and adult Schistosoma japonicum parasites which apparently encodes a new member of the TM4SF. The deduced polypeptide, termed Sj25/TM4, has substantial amino acid homology to Sm23 from Schistosoma mansoni although it is not a species homologue of Sm23. Sj25/TM4 is predicted to span the cell membrane four times, with its NH2 and COOH-termini embedded in the cytoplasm, and to have two extracellular hydrophilic loops, one of which may be N-glycosylated. This topology is characteristic of TM4SF proteins; in addition, Sj25/TM4 contains the sequence motifs conserved in the TM4SF. Southern hybridization analysis demonstrated that Sj25/TM4 and Sj23 are encoded by genes at separate loci and, further, showed interstrain variation at the locus encoding Sj25/TM4 in Chinese and Philippine isolates of S. japonicum. PMID- 9370242 TI - Characterization of the effects of amphotericin B on ion channels in MDCK cells using the patch-clamp technique. AB - Cultured Madin-Darby Canine Kidney cells were used as a model to study the mechanism of nephrotoxicity of amphotericin B using the patch-clamp technique. At the whole-cell level, amphotericin B altered potassium conductances in two types of these cells categorized on the basis of whole-cell potassium currents. The first cell type, classified as Type I, exhibited no significant whole-cell potassium currents. The second type, Type II, exhibited depolarization-induced outward potassium currents that rundown over time. In both of these subpopulations, exposure to amphotericin B at a concentration of 68 nM for a prolonged period of time (approximately 30-45 min) led to an increased whole-cell potassium conductance. In Type I cells, it increased by a factor of 16 and in Type II cells, by a factor of 3.5. Furthermore, the potassium currents observed in Type I cells following amphotericin B treatment bore no resemblance to currents through pores formed by amphotericin B in artificial membranes. At the single-channel level, incubation with amphotericin B led to a significantly higher potassium channel activity in both inside-out and outside-out patches. Kinetic studies in inside-out patches revealed that the increases in channel activity were associated with a decrease in the mean closed time and an overall increase in the mean open time. In summary, our data suggest that the direct toxicity of amphotericin B is primarily related to its ability to disturb normal ion channel functioning rather than to formation of pores in cell membranes. PMID- 9370243 TI - Entrapment of nucleic acids in liposomes. AB - The entrapment efficiency of three main methods used in the literature for the encapsulation of nucleic acids in liposomes were studied using 1-palmitoyl-2 oleoyl-sn-glycero-3-phosphocholine (POPC) liposomes. In particular the reverse phase method, the dehydration/rehydration method, and the freeze/thawing method were compared to each other under standardised conditions, i.e. using in every case the same concentration of guest molecules (DNA, tRNA and ATP as low molecular weight analogue) and equally extruded liposomes. The percentage of entrapment strictly referred to the material localized inside the liposomes, i.e. particular care was devoted to ruling out the contribution of the nucleic acid material bound to the outer surface of the liposomes: this was eliminated by extensive enzymatic digestion prior to column chromatography. Depending on the conditions used, the percentage of the entrapped material varied between 10 and 54% of the initial amount. Further, the encapsulation efficiency was markedly affected by the salt concentration, by the size of liposomes, but to a lower degree by the molecular weight of the guest molecules. In general, we observed that the freeze/thawing encapsulation procedure was the most efficient one. In a second part of the work the freeze/thawing method was applied to encapsulate DNA (369 bp and 3368 bp, respectively) using liposomes obtained from POPC mixed with 1-10% charged cosurfactant, i.e. phosphatidylserine (PS) or didodecyldimethylammonium bromide (DDAB), respectively. Whereas PS had no significant effect, the entrapment efficiency went up to 60% in POPC/DDAB (97.5:2.5) liposomes. The large entrapment efficiency of DNA permits spectroscopic investigations of the DNA encapsulated in the water pool of the liposomes. UV absorption and circular dichroism spectra were practically the same as in water, indicating no appreciable perturbation of the electronic transitions or of the conformation of the entrapped biopolymer. This was in contrast to the DNA bound externally to the POPC/DDAB liposomes which showed significant spectral changes with respect to DNA dissolved in water. PMID- 9370244 TI - The hinge portion of the S. aureus alpha-toxin crosses the lipid bilayer and is part of the trans-mouth of the channel. AB - This paper compares the functional properties of ion channels formed in planar lipid membranes by the wild and mutant Staphylococcus aureus alpha-toxin. It was shown that replacement of the amino acid Gly at position 130 by Cys in the primary structure of the toxin decreases the single-channel conductance with a concomitant decrease in the pH at which the channel becomes unable to discriminate between Cl- and K+ ions. The mutation also induced an increase in the asymmetry in the current-voltage relationship of the channel. The results of our experiments suggest that the trans-mouth of the channel is responsible for all the observed changes in channel properties. It was assumed that this entrance is built by the glycine-rich hinge portion of the toxin and is situated close to the surface of monolayer facing the trans-compartment. PMID- 9370245 TI - Interlamellar waters in dimyristoylphosphatidylethanolamine-water system as studied by calorimetry and X-ray diffraction. AB - The number of water molecules incorporated into the interlamellar region in a gel phase of dimyristoylphosphatidylethanolamine (DMPE)-water system containing up to about 40 g% water was estimated by techniques of calorimetry and X-ray diffraction. The calorimetric estimation based upon enthalpy changes of deconvoluted ice-melting peaks revealed that bulk water existing outside lipid bilayers begins to appear although the gel phase is not fully hydrated. The gel phase showed a linear depression of its transition temperature proportional to the amount of freezable waters interposed between bilayers. For a fully hydrated gel phase, the numbers of non-freezable and freezable interlamellar waters estimated by calorimetric analysis were about 2.3 and 3.7 molecules per lipid, respectively. The limiting, total number of interlamellar waters, 6 H2O/lipid, agreed with that estimated from both the X-ray diffraction data and the absolute specific volume for a DMPE molecule. Furthermore, the analysis for the lamellar intensity data is also consistent with the result of calorimetric analysis. PMID- 9370246 TI - Estimating the electrostatic potential at the acetylcholine receptor agonist site using power saturation EPR. AB - Continuous wave EPR power saturation was used to measure electrostatic potentials at spin-labeled sites. Membrane surface potentials were estimated by power saturating the EPR spectrum of a membrane bound 14N spin-labeled amphiphile in the presence of a neutral or positively charged 15N labeled aqueous spin probe. The potentials that are measured are in good agreement with other probe measurements and with the predictions of the Gouy-Chapman-Stern theory, indicating that this is a valid approach to determine electrostatic potentials. A spin-labeled affinity probe based on maleimidobenzyltrimethylammonium was synthesized and could be derivatized to a sulfhydryl near either agonist site on the nicotinic acetylcholine receptor. The amplitudes of motion of the spin-probe on the ns time scale are significantly different when the two labeled sites are compared, and the probe is more restricted in its motion when attached to the more easily labeled site. When attached to this agonist site, power saturation EPR yields an electrostatic potential of -15 mV. Two other sulfhydryl-specific probes were used to label this site in reconstituted receptor containing membranes. These probes show less contact with the receptor and reduced electrostatic potentials, indicating that there is a strong spatial dependence to the potential at the agonist site. This work demonstrates that power saturation EPR provides a general method that can be used to estimate electrostatic potentials at any specifically spin-labeled macromolecular site. PMID- 9370247 TI - Phase behavior and permeability properties of phospholipid bilayers containing a short-chain phospholipid permeability enhancer. AB - The thermodynamic phase behavior and trans-bilayer permeability properties of multilamellar phospholipid vesicles containing a short-chain DC10PC phospholipid permeability enhancer have been studied by means of differential scanning calorimetry and fluorescence spectroscopy. The calorimetric scans of DC14PC lipid bilayer vesicles incorporated with high concentrations of DC10PC demonstrate a distinct influence on the lipid bilayer thermodynamics manifested as a pronounced freezing-point depression and a narrow phase coexistence region. Increasing amounts of DC10PC lead to a progressive lowering of the melting enthalpy, implying a mixing behavior of the DC10PC in the bilayer matrix similar to that of a substitutional impurity. The phase behavior of the DC10PC-DC14PC mixture is supported by fluorescence polarization measurements which, furthermore, in the low-temperature gel phase reveal a non-monotonic concentration-dependent influence on the structural bilayer properties; small concentrations of DC10PC induce a disordering of the acyl chains, whereas higher concentrations lead to an ordering. Irreversible fluorescence quench measurements demonstrate a substantial increase in the trans-bilayer permeability over broad temperature and composition ranges. At temperatures corresponding to the peak positions of the heat capacity, a maximum in the trans-bilayer permeability is observed. The influence of DC10PC on the lipid bilayer thermodynamics and the associated permeability properties is discussed in terms of microscopic effects on the lateral lipid organization and heterogeneity of the bilayer. PMID- 9370248 TI - Hepatic microsomal membrane lipidic composition and growth hormone effect in adult male rat: evidence for a 'feminization' process of total phospholipid fatty acid pattern. AB - Growth hormone (GH) effects on fatty acid composition and on delta5-, delta6-, delta9-desaturase and palmitic acid elongation activities were studied in male rat hepatic microsomes. Sham-operated and hypophysectomized animals were injected with two different dosages of GH, mimicking either the male or female GH secretion pattern. Half the hypophysectomized animals received thyroxine and cortisol in concentrations chosen to compensate for the lack of thyroid hormones and glucocorticoids. GH, administered to sham-operated or to cortisol/thyroxine treated hypophysectomized rats resulted in an increase in stearic and arachidonic acid proportions, while palmitic acid percentage was decreased. Total monounsaturated fatty acids were dramatically reduced by this treatment. DeltaA desaturase and palmitic acid elongation activities were increased by GH treatment, while delta9-desaturase activity was decreased. These GH effects on desaturation and elongation activities could explain the modifications in microsomal fatty acid composition. Hypophysectomy markedly altered the fatty acid composition by reducing arachidonic and stearic acid proportions and increasing the linoleic acid proportion, while delta9-, delta5-desaturase and palmitic acid elongation activities were decreased. Restoration of most of the fatty acid proportions to control values was realized in hypophysectomized animals with a cortisol/thyroxine replacement administered alone or together with the low dosage of GH mimicking the male secretion pattern. High GH dosage produces essentially a 'feminization' process of the fatty acid composition of the hepatic microsomal membrane in male rats when compared to that of females. PMID- 9370249 TI - Functional consequences of mutations in the transmembrane domain and the carboxy terminus of the murine AE1 anion exchanger. AB - We have characterized mouse AE1-mediated 36Cl- influx and surface AE1 polypeptide expression in Xenopus oocytes injected with cRNA encoding two classes of loss-of function mutants. The first arose spontaneously. Chimeric mutants constructed with a functional AE1 cDNA localized the site of spontaneous mutation to the transmembrane domain, and DNA sequencing revealed two missense mutations encoding the double-mutant polypeptide V728F/M7301. Each mutation individually produced only partial loss of AE1 transport activity, and coexpression of the individual mutants did not restore full activity. The functional changes produced by the mutations correlated with reduced fractional accumulation of polypeptides at the oocyte surface. The V728F/M7301 polypeptide expressed in mammalian cells displayed complete endoH resistance and rapid degradation. We also examined the effect on AE1 function of engineered removal of its hydrophilic carboxy-terminus. Both delta(c)890 and the internal deletion delta(c)890-917 were functionally inactive in Xenopus oocytes. Lack of transport activity correlated with lack of detectable polypeptide accumulation at the oocyte surface. Coexpression with wt AE1 of some, but not all, of these AE1 mutants partially suppressed wt AE1 mediated 36Cl- uptake. In contrast, coexpression with wt AE1 of soluble N terminal AE1 fragments was not inhibitory. PMID- 9370250 TI - The headgroup orientation of dimyristoylphosphatidylinositol-4-phosphate in mixed lipid bilayers: a neutron diffraction study. AB - The trisodium salt of dimyristoylphosphatidylinositol-4-phosphate (DMPI-4P) has been synthesised specifically deuterated at particular sites in the headgroup. These materials have been used in neutron diffraction experiments, which successfully located the position (depth) of each of these deuterated sites to within +/- 0.5 A in a mixed model membrane (a 1:1 molar mixture of DMPI-4P with dimyristoyl-phosphatidylcholine, DMPC, in the L alpha phase, hydrated to the level of 28 water molecules per lipid molecule). The diffracted intensities were measured at four different D2O/H2O ratios and six orders of diffraction were obtained. These data sets, in conjunction with computer modelling, have been used to determine the orientation of the inositol ring of DMPI-4P, localising each vertical H-H distance to within approximately +/- 0.03 A. The orientation of the inositol ring is found to be one in which the C5 hydroxyl is extended out into the aqueous medium. This is, therefore, the most accessible site for water-borne reagents. This may be significant for the important pathway leading from PI-4P to PI-4,5P2. On the assumption that the P/ODAG bond is orientated parallel to the bilayer normal, these results are consistent with two possible conformations for the portion of the headgroup connecting the diacylglycerol to the inositol ring. Distinction between these two is difficult, but one may be favoured since the other involves close atom-atom contacts. PMID- 9370251 TI - Stability of association of 1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine with liposomes is composition dependent. AB - The ether lipid, 1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine (ET-18 OCH3), has anticancer activity, but it has serious side-effects, including hemolysis, which prevent its optimal use. We surmised if ET-18-OCH3 could be stably associated with liposomes, less free ET-18-OCH3 would be available for lytic interaction with red cells. Liposome composition variables investigated included acyl chain saturation, phospholipid head group and mole ratio of Chol and ET-18-OCH3. It was found that attenuation of hemolysis was strongly liposome composition dependent. Some ET-18-OCH3 liposome compositions were minimally hemolytic. For example, whereas the HI5 (drug concentration required to cause 5% human red cell lysis) was 5-6 microM for free ET-18-OCH3, it was approximately 250 microM for DOPC (dioleoylphosphatidylcholine):Chol (cholesterol):DOPE-GA (glutaric acid derivatized DOPE):ET-18-OCH3, (4:3:1:2) and 640 microM for DOPE (dioleyolphosphatidylethanolamine):Chol:DOPE-GA:ET-18-OCH3 (4:3:1:2) liposomes. Efflux of carboxyfluorescein (CF) from liposomes and Langmuir trough determinations of mean molecular area of lipids in monolayers (MMAM) were used as indicators of membrane packing and stability. Incorporation of ET-18-OCH3 in liposomes reduced the MMAM. Reduction in CF permeation was correlated with reduction in hemolysis. The most stable liposomes included components, such as cholesterol, DOPC and DOPE, which have complementary shapes to ET-18-OCH3. PMID- 9370253 TI - The effect of phloretin on the hydration of egg phosphatidylcholine multilayers. AB - The effect of phloretin on the hydration, structure and interactive properties of supported phospholipid bilayers has been studied by a combination of direct water adsorption measurements and X-ray diffraction. Adsorption isotherms show that over a wide range of relative vapor pressures (from 0 to approximately 1.0) the addition of 20 or 40 mol% phloretin significantly alters the amount of water adsorbed by egg phosphatidylcholine (EPC) multilayers. X-ray diffraction analysis shows that the incorporation of phloretin decreases the width of the EPC bilayer, thereby increasing the area per lipid molecule from approximately 64 A2 for EPC to about 78 A2 for EPC:Ph, 3:2, M:M. Phloretin also decreases the distance between apposing EPC bilayers, most likely because it causes a reduction in repulsive hydration/steric pressure between apposing bilayers. Because phloretin decreases the fluid layer between bilayers by a larger amount than it increases the area per EPC molecule, phloretin has the effect of decreasing the water volume in the multilayers. PMID- 9370252 TI - New fluorescent lysolipids: preparation and selective labeling of inner liposome leaflet. AB - Two new fluorescent lysophosphatidylcholine probes have been synthesized for use as a donor-acceptor pair in fluorescence resonance energy transfer (FRET): 9 anthrylvinyl (LAPC) as donor and 3-perylenoyl (LPPC) as acceptor. The partition coefficients between membrane and aqueous phases were 8.3 x 10(5) and 10.5 x 10(5) for LAPC and LPPC, respectively. The inner leaflets of unilamellar lipid vesicles were labeled with these probes to assess conservation of membrane sidedness after membrane fusion. After medium-sized unilamellar vesicles (MUV) were prepared with a probe in both leaflets, probe in the outer leaflet was removed by repeatedly washing with an excess of unlabeled giant unilamellar vesicles (GUV). MUV and GUV were separated by centrifugation. The probes did not flip-flop across bilayers at 25 degrees C for at least 12 h. MUV containing the ganglioside GT1b were labeled with the LAPC/LPPC pair in the inner leaflet and incubated for 30 min at neutral pH with influenza virus. Fusion was triggered by acidification to pH 5.0 and was monitored by an increase in donor fluorescence in a FRET assay. When the inner leaflets of MUV were labeled by LAPC only, its fluorescence did not change after fusion. However, the fluorescence decreased by 60% when the LAPC was removed from the outer leaflets of the fused membranes by repeated washings with GUV. We conclude that the lipids of the inner and outer leaflets of the fused MUV/virus complexes intermixed. PMID- 9370255 TI - Effect of dicetylphosphate or stearic acid on spontaneous transfer of protein from influenza virus-infected cells to dimyristoylphosphatidylcholine liposomes. AB - Membrane proteins, such as viral spike, were transferred spontaneously from influenza virus-infected cells to various liposomes. The protein transfer was enhanced by the presence of negative charged component dicetylphosphate (DCP) or stearic acid (SA) in dimyristoylphosphatidylcholine (DMPC) liposomes. The lowering of membrane fluidity did not relate to the effect of DCP or SA on protein transfer in this study. We considered that the alteration of membrane properties, such as construction of the surface or stability of transferred protein in liposomes, due to the specific structure of DCP or SA is responsible for the enhancement of spontaneous protein transfer by the presence of the amphiphilic components. PMID- 9370254 TI - Lack of effect of transmembrane gradient of magnesium and sodium on regulation of cytosolic free magnesium concentration in rat lymphocytes. AB - The regulation of the intracellular concentration of Mg2+ ([Mg2+]i) is not fully understood. The level of Mg in lymphocytes is a good predictor of total body Mg status. We measured [Mg2+]i and total Mg in rat lymphocytes by using, respectively, the fluorescent Mg2+ indicator mag-fura-2 and atomic absorption spectrophotometry. The basal [Mg2+]i in rat lymphocytes was 328 +/- 23 micromol/l. An elevation to 5 mmol/l or the removal of extracellular Mg2+ did not affect [Mg2+]i. A reduction in extracellular Na+ did not influence [Mg2+]i for 60 min. The total Mg concentration in lymphocytes also remained stable. Results suggest that the permeability of the plasma membrane to Mg2+ is very low, and that Na+/Mg2+ exchange is not involved in the regulation of [Mg2+]i in rat lymphocytes. PMID- 9370256 TI - Conformational studies of synthetic lipid A analogues and partial structures by infrared spectroscopy. AB - Synthetic lipid A analogues and partial structures were analyzed and compared with natural hexaacyl lipid A from E. coli applying Fourier transform infrared spectroscopy. The investigations comprised (i) the measurement of the beta <=> alpha phase transition of the acyl chains via monitoring of the symmetric stretching vibration of the methylene groups, (ii) an estimation of the supramolecular aggregate structures evaluating vibrations from the interface like ester carbonyl and applying theoretical calculations (iii) a determination of the inter- and intramolecular conformations monitoring functional groups from the interface and the diglucosamine backbone (ester carbonyl, phosphate). The phase transition temperature Tc was found to be nearly a linear function of the number of acyl chains for most bisphosphoryl compounds indicating comparable packing density, whereas the deviating behaviour of some samples indicated a higher packing density. From the determination of the supramolecular aggregate structures (cubic, HII) of natural hexaacyl lipid A by X-ray small-angle diffraction, the existence of the same aggregate structures also for the synthetic hexaacyl lipid A was deduced from the nearly identical thermotropism of the ester carbonyl band. From this, a good approximation of the supramolecular structures of all synthetic samples was possible on the basis of the theory of Israelachvili. The analysis of the main phosphate band, together with that of the Tc data and former colorimetric results, allowed the establishment of a model of the intermolecular conformations of neighbouring lipid A/LPS molecules. The biological relevance of the findings is discussed in terms of the strongly varying biological activity (between high and no activity) of the samples. PMID- 9370257 TI - Correction to "Is vitrification involved in depression of the phase transition temperature in dry phospholipids?" [Biochim. Biophys. Acta 1280 (1996) 187-196]. PMID- 9370258 TI - Quantification of alternatively spliced RUSH mRNA isoforms by QRT-PCR and IP-RP HPLC analysis: a new approach to measuring regulated splicing efficiency. AB - Quantitative reverse transcriptase-polymerase chain reaction (QRT-PCR) and the ion-pair reverse-phase (IP-RP)-HPLC product purification and detection system were developed to facilitate the isolation and proportional quantification of alternatively spliced RUSH mRNAs. RUSH isoforms result from alternative splicing of a 57-bp exon and encode SNF/SWI-related proteins that bind to the uteroglobin promoter. QRT-PCR was performed using total RNA, and a pair of primers designed to flank the 57-bp exon. When more than one splice variant was expressed, IP-RP HPLC identified the specific homoduplex products, as well as the heteroduplexes formed as a consequence of partial sequence complementarity between the products. Data analysis included the correct re-allocation of heteroduplex components to achieve accurate quantitation of changes in the relative levels of RUSH message isoforms. The preferential expression of the RUSH-1alpha isoform by all the tissues except estrous uterine endometrium and lactating mammary gland indicates RUSH pre-mRNAs are alternatively spliced in a tissue-specific manner. A 61-fold difference in the relative rate of RUSH pre-mRNA splicing is indicated by the difference in the ratios of RUSH mRNA isoforms from uterine endometrium and testis. Clearly, QRT-PCR and IP-RP-HPLC are powerful and versatile tools for the detection and quantitation of mRNA splice variants. PMID- 9370259 TI - Characterization of a Schistosoma mansoni gene encoding a homologue of the Y-box binding protein. AB - We have cloned and characterized a Schistosoma mansoni cDNA encoding a basic protein homologous to the human Y-box binding protein 1 (YB-1). The 1.3-kb S. mansoni YB-1 transcript, which was shown to be expressed in various stages of the parasite life cycle, codes for a protein of 217 amino acids containing, towards its N-terminus, a nucleic acid binding motif, known as the cold-shock domain (CSD). This domain is 64% identical to the cold-shock domain of other members of the Y-box binding protein family and 43% identical to the cold-shock protein CspA of Escherichia coli. In S. mansoni YB-1, the cold-shock domain possess some structural characteristics that permit dimer formation as occurs in the Bacillus subtilis cold-shock protein CspB. The C-terminal region of S. mansoni YB-1 differs from the other Y-box binding proteins because of the presence of tandem repeats of Arg and Gly, suggesting the formation of a fibroin-like beta-sandwich structure. This novel folding pattern for the C-terminus of S. mansoni YB-1 might suggest a distinct specific function for this protein in the parasite. PMID- 9370260 TI - viking: identification and characterization of a second type IV collagen in Drosophila. AB - We have taken an enhancer trap approach to identify genes that are expressed in hematopoietic cells and tissues of Drosophila. We conducted a molecular analysis of two P-element insertion strains that have reporter gene expression in embryonic hemocytes, strain 197 and vikingICO. This analysis has determined that viking encodes a collagen type IV gene, alpha2(IV). The viking locus is located adjacent to the previously described DCg1, which encodes collagen alpha1(IV), and in the opposite orientation. The alpha2(IV) and alpha1(IV) collagens are structurally very similar to one another, and to vertebrate type IV collagens. In early development, viking and DCg1 are transcribed in the same tissue-specific pattern, primarily in the hemocytes and fat body cells. Our results suggest that both the alpha1 and alpha2 collagen IV chains may contribute to basement membranes in Drosophila. This work also provides the foundation for a more complete genetic dissection of collagen type IV molecules and their developmental function in Drosophila. PMID- 9370261 TI - Insertional mutagenesis by a modified in vitro Ty1 transposition system. AB - Transposable elements are useful tools for insertional mutagenesis and have many potential applications in the characterization of complex genomes. Here we describe a system which facilitates the construction of large transposon insertion libraries useful for genome sequencing and functional genomic analysis. We developed two transposons, TyK and TyK'GFP+, which can be introduced into target DNAs by Ty1-mediated transposition in vitro, and several modifications which decrease the frequency of false transposition events and direct the recovery of transpositions into passenger rather than vector DNA. Insertions of TyK'GFP+ additionally may yield fusions to the Aequorea green fluorescent protein (GFP), useful in studies of gene expression and protein targeting. Transposition in vitro was obtained into target DNAs of up to 50 kb in size, restriction mapping showed insertion to be relatively random, and the sequence of 55 insertion sites showed neither strong site nor base compositional preference. Our data suggest that TyK-based artificial transposons will be suitable for a variety of genetic applications in many organisms. PMID- 9370262 TI - A phosphoglycerate mutase brain isoform (PGAM 1) pseudogene is localized within the human Menkes disease gene (ATP7 A). AB - We have identified a phosphoglycerate mutase brain isoform (PGAM 1, PGAM B) cDNA that is localized between exons 1 and 2 of the Menkes disease gene (ATP7 A, MNK) at Xq13.3. The cDNA shows 98% identity to the previously identified PGAM 1 cDNA (Sakoda et al., J. Biol. Chem. 263 (1988) 16899-16905) and probably represents a recent retroposition of this parent PGAM 1 mRNA. Although the typical features of a processed pseudogene are present, the open reading frame (ORF) of this PGAM cDNA is potentially expressed. There are 11 bp changes in the 765 bp ORF, none of which are nonsense mutations or deletions. The region upstream from the ORF shows some features of a possible promoter region, although it lacks a CpG island often associated with functional promoters. We analyzed the expression of this PGAM 1 cDNA using RT-PCR followed by restriction enzyme digestion based on a 1 bp missmatch in this cDNA to distinguish it from normal PGAM 1 gene expression. With this sensitive method, we could not find expression in any of the tissues examined. Taken together, we conclude that the PGAM 1 cDNA upstream from exon 2 of the Menkes gene is likely to be a processed pseudogene originating from a very recent retroposition of a PGAM 1 transcript. To our knowledge this is the first report of a pseudogene located within a gene. PMID- 9370264 TI - Cloning and expression of three members of the zebrafish Bmp family: Bmp2a, Bmp2b and Bmp4. AB - In vertebrates, Bmps (bone morphogenetic proteins) play critical roles in establishing the basic embryonic body plan and are involved in the development of a large variety of organs and tissues. To study the evolution of Bmps, we isolated cDNAs for three members of the zebrafish Bmp gene family: Bmp2a, Bmp2b and Bmp4. The deduced amino acid sequences of Bmp2a and Bmp4 consist of 386 and 400 aa, respectively and show high homologies to their counterparts in mouse, chick and Xenopus. The deduced Bmp2b aa sequence consists of 411 aa and the mature protein shows 88% and 86% identities to zebrafish Bmp2a and Bmp4, respectively. The expression of the mRNA of these three genes has been analyzed by whole mount in situ hybridization and RT-PCR. Areas of zebrafish Bmp2 and Bmp4 expression suggest evolutionary conserved mechanisms of Bmp2/4 dependent differentiation between lower and higher vertebrates. PMID- 9370263 TI - The ER chaperone encoding bipA gene of black Aspergilli is induced by heat shock and unfolded proteins. AB - We describe the cloning and characterisation of the BiP gene homologues of the filamentous fungi Aspergillus niger and Aspergillus awamori. The BiP genes of these black Aspergilli encode an identical protein of 672 amino acids, which has a high homology with the BiP protein from Saccharomyces cerevisiae and contains a putative signal sequence of 38 amino acids. The DNA sequences of the Aspergillus BiP genes diverge in particular in the three intronic sequences and the 5'- and 3'- noncoding regions. Sequences resembling Heat Shock Elements (HSE) and Unfolded Protein Response (UPR) elements, as found in the yeast KAR2 promoter, are present in the 5' non-transcribed regions of both genes. The expression of the A. niger bipA gene is increased by heat shock and tunicamycin treatment. PMID- 9370265 TI - Molecular cloning and chromatin structure analysis of the murine alpha1(I) collagen gene domain. AB - We have isolated molecular clones of genomic mouse DNA spanning 55 kb, including the entire coding region of the murine alpha1(I) collagen (Col1a1) gene and 24 kb of 5' and 13 kb of 3'-flanking sequences, and have performed a detailed chromatin structure analysis of these sequences. Several new DNase-I-hypersensitive sites were identified. The distal 5'-flanking region contains two clusters of DNase-I hypersensitive sites located between 7 and 8 kb and between 15 and 20 kb upstream of the start site of transcription, respectively. Several of these sites were shown to be present in collagen-producing, but not in non-producing cells, indicating that they are associated with transcription of the gene and may function in its regulation. One strong constitutive DNase-I-hypersensitive site at -18.5 kb was also cleaved by endogenous nucleases. The 3'-flanking region of the gene contains a DNase-I-hypersensitive site located 6 kb downstream of the end of the gene, as well as sequences that can induce a non-B DNA structure. Because these latter sequences coincide with DNase-I-hypersensitive sites in the homologous human gene, our results suggest that some regulatory elements may play a role in gene regulation, not by specific protein-DNA interactions but by virtue of their ability to induce a non-B DNA structure and/or an alternate chromatin conformation. A comparison of the murine and human Col1a1 domains shows a similar, although not identical, distribution of DNase-I-hypersensitive sites, indicating a conserved arrangement of regulatory elements. Our results strongly suggest that these new sites constitute regulatory elements which are involved in the transcriptional regulation and/or chromatin loop organization of the Col1a1 gene, and they are now amenable for functional analyses. PMID- 9370266 TI - Cloning, sequencing and regulation of thiA, a thiamin biosynthesis gene from Bacillus subtilis. AB - The thiA gene is involved in the biosynthesis of the pyrimidine moiety of thiamin in Bacillus subtilis. This gene was cloned using a DNA probe rescued from thiA::Tn917 to screen a B. subtilis genomic library. ThiA exhibits 70% identity with E. coli thiC. The proposed thiA open reading frame complements all available thiA mutants of B. subtilis as well as the thiC mutant of E. coli. This suggests a similar biosynthetic pathway to 2-methyl-4-amino-5-hydroxymethylpyrimidine in both organisms. The expression of thiA is regulated, at least on the transcriptional level, and is significantly repressed by thiamin and 2-methyl-4 amino-5-hydroxymethylpyrimidine. PMID- 9370267 TI - Distribution of human endogenous retroviral RTVL-H2 LTR sequences among human chromosomes. AB - The human genome carries multiple copies of sequences related to endogenous retroviral DNA. We report here the distribution of a new multicopy long terminal repeat (LTR) sequence that has been a part of an endogenous retrovirus-like sequence RTVL-H2. Twenty-four human chromosomes were either separated by flow sorting or by using rodent cells carrying a single human chromosome, and the DNA was subjected to Southern analyses using the RTVL-H2 DNA as a probe. The RTVL-H2 LTRs were distributed among all the human chromosomes, but the density and the profile differed from chromosome to chromosome. The same chromosome obtained from different individuals showed essentially the same chromosome-specific patterns. The distribution of the RTVL-H2 LTRs among different chromosomes did not correlate with the distribution of LTRs from another endogenous retroviral DNA, HERV-A, strongly suggesting that there is no preferred chromosome or a region thereof, for the integration. The possibility of rearrangement or amplification after integration is discussed. PMID- 9370268 TI - The normally silent sigma54 promoters upstream of the pilE genes of both Neisseria gonorrhoeae and Neisseria meningitidis are functional when transferred to Pseudomonas aeruginosa. AB - The pilE gene encodes the pilin subunit in Neisseria gonorrhoeae and Neisseria meningitidis. Transcriptional analysis of promoters upstream of pilE in N. gonorrhoeae has been described previously (Fyfe et al. (1995) J. Bacteriol. 177, 3781-3787). Transcription from the sigma54-dependent promoter P3 was detected in Pseudomonas aeruginosa. Here we show that this transcription is dependent on the P. aeruginosa transcriptional activator PilR, and a specific upstream sequence with a high degree of similarity to the PilR-binding site found upstream of the P. aeruginosa pilin gene. This implies there is an upstream activator site (UAS) present 5' of pilE. Sequencing upstream of the N. meningitidis MC58 c2 pilE gene shows this region to be very similar to that in N. gonorrhoeae. P3 and the UAS are conserved, although insertions were noted on either side of the UAS. Transcriptional analysis has shown that the N. meningitidis P3 promoter is used in P. aeruginosa, provided PilR and an upstream region that includes sequence similar to the UAS are present. Transcription from the N. meningitidis PpilE is stronger than from the N. gonorrhoeae equivalent. N. meningitidis uses the sigma70 promoter P1 to transcribe pilE. PMID- 9370269 TI - Filamentous phage infection-mediated gene expression: construction and propagation of the gIII deletion mutant helper phage R408d3. AB - We describe the use of transcriptional fusions to the phage shock protein (psp) promoter. These fusions are expressed only when cells are infected by filamentous phage. In an application, the psp promoter was fused to the protein coding part of filamentous phage gene III (gIII). Protein III (pIII) is needed to complement mutant f1 phage containing a deletion of gIII, but its synthesis also renders cells resistant to infection. By inducing pIII production from psp-gIII only in the cells that are already infected with phage, it was possible to obtain plaques from phage in which gIII had been completely deleted. gIII was deleted from two helper phages: R408 and VCSM13, which were then propagated on cells containing the psp-gIII fusion. These two phages were tested for use in a phage display method that requires generation of noninfectious, phagemid-containing virion-like particles. Both helpers worked, but R408d3 was superior to VCSM13d3, because it generated about 1800-times fewer background infectious particles. PMID- 9370270 TI - Salmonella typhimurium specifies a circular chromosome dimer resolution system which is homologous to the Xer site-specific recombination system of Escherichia coli. AB - The Xer site-specific recombination system of Escherichia coli resolves both chromosome dimers and multimers of certain plasmids including those of ColE1. In this manner, Xer site-specific recombination contributes to the accurate distribution of circular chromosomes at cell division. Two related site-specific recombinases, XerC and XerD, are required for this process. The xerC and xerD genes of Salmonella typhimurium LT2 were isolated from libraries of LT2 genomic DNA by genetic complementation of E. coli Xer mutants. The putative proteins specified by the S. typhimurium genes can substitute for and are highly homologous to the corresponding proteins in E. coli. The distribution of amino acid dissimilarities differs, however, between pairs of cognate Xer proteins. The immediate genetic contexts of equivalent xer genes, i.e., in operons with genes of apparently unrelated function, are conserved between the two bacteria. This is the first description of the identification of a pair of functional homologues of the xerC and xerD genes of E. coli. PMID- 9370271 TI - Evolutionary relationship among rfb gene clusters synthesizing mannose homopolymer as O-specific polysaccharides in Escherichia coli and Klebsiella. AB - In order to clarify the evolutionary relationship among rfb gene clusters synthesizing mannose homopolymer as O-specific polysaccharides in Escherichia coli and Klebsiella, we studied the DNA sequence of the boundary region between the rfb and his genes in a series of strains possessing mannose homopolymer as O specific polysaccharide. All had a characteristic gene organization carrying no gene between the rfb and his genes. Further, the recombination event was suggested to occur at the same site of the hisI gene in those strains. It was suggested that there was a close evolutionary relationship among rfb gene clusters synthesizing mannose homopolymer as O-specific polysaccharide in E. coli and Klebsiella. PMID- 9370273 TI - Functional characterization of bovine von Willebrand factor gene promoter in bovine endothelial cells demonstrates species-specific properties. AB - Von Willebrand factor (vWF), a protein necessary for platelet adhesion and thrombus formation, is specifically synthesized in endothelial cells and in platelet precursors (megakaryocytes). We previously demonstrated that the sequences localized either in the 5'-flanking region or in the first exon of human (hu) vWF gene (vWF), which regulate the cell-specific transcription, are not conserved in the bovine counterpart. In order to look for cis-acting elements involved in the endothelial expression of bovine (bo) vWF, fragments including 113 base pairs (bp) of a sequence 5'-flanking the transcription start point (tsp, +1) and various deletions of the first 233 bp exon were linked in plasmids to the bacterial chloramphenicol (Cm) acetyltransferase gene (cat). These constructs were analyzed by transient transfection in calf pulmonary artery endothelial (CPAE), human epithelial (HeLa) from cervix and green monkey fibroblasts from kidney (COS) cells. The longest fragment, containing 229 bp of the first exon, was the most active, with identical cat expression in the three cell types. The CAT activity was equivalent to that measured by transfection of the same cells with the basal promoter (from bp -89 to +19) of hu vWF. Addition of upstream bo vWF sequences from bp -113 to -1362 resulted in progressive reduction of the activity of the -113/+229 fragment. The upstream negative regulatory domains between -1362 and -278 also repressed the heterologous thymidine kinase (tk) promoter in CPAE and HeLa cells. Comparison of results with those previously obtained by transfection of hu vWF promoter in bovine endothelial cells demonstrates that the cis-acting elements do not behave identically in bo vWF promoter. In particular, positive tissue-specific elements able to overcome the negative regulation in endothelial cells could not be found in bo vWF between bp 1362 and +229. PMID- 9370274 TI - Cloning and sequencing of two genes, prtA and prtB, from Myxococcus xanthus, encoding PrtA and PrtB proteases, both of which are required for the protease activity. AB - The sequence of a 1955-bp TaqI DNA fragment from Myxococcus xanthus was determined. This fragment contains two complete genes, designated prtA and prtB. The prtA and prtB ORFs extend over 828 and 798 bp, respectively. They are separated only by 3 nt and appear to be present in a polycistronic transcriptional unit. A typical lipoprotein signal sequence is present at the N terminus of the two deduced polypeptides. The aa sequence of PrtA shows a high degree of identity to the region adjacent to the Ser residue belonging to the catalytic triad of serine proteases from Staphylococcus aureus and Enterococcus faecalis. It also exhibits features characteristic of trypsin-like serine proteases in that it contains the same pattern of variable and conserved regions. The deduced aa sequence of PrtB reveals a signature zinc-binding consensus motif (HEXXHXXGXXH/Met-turn) characteristic of the class of metalloproteases called metzincins. Plasmids containing prtA, prtB, or both were constructed. Protease activity studies of Escherichia coli clones containing these plasmids showed that both genes are necessary for this activity, whatever their cis or trans position. As prtB produces a putative membrane-bound lipoprotein of 266 aa, the protease activation must occur at the membrane level. PMID- 9370272 TI - The Deinococcus radiodurans uvr A gene: identification of mutation sites in two mitomycin-sensitive strains and the first discovery of insertion sequence element from deinobacteria. AB - Deinococcus radiodurans (Dr) possesses a prominent ability to repair the DNA injury induced by various DNA-damaging agents including mitomycin C (MC), ultraviolet light (UV) and ionizing radiation. DNA damage resistance was restored in MC sensitive (MC(S)) mutants 2621 and 3021 by transforming with DNAs of four cosmid clones derived from the gene library of strain KD8301, which showed wild type (wt) phenotype to DNA-damaging agents. Gene affected by mutation (mtcA or mtcB) in both mutants was cloned and its nucleotide (nt) sequence was determined. The deduced amino acid (aa) sequence of the gene product consists of 1016 aa and shares homology with many bacterial UvrA proteins. The mutation sites of both mutants were identified by analyzing the polymerase chain reaction (PCR) fragments derived from the genomic DNA of the mutants. A 144-base pair (bp) deletion including the start codon for the uvrA gene was observed in DNA of the mutant 3021, causing a defect in the gene. On the other hand, an insertion sequence (IS) element intervened in the uvrA gene of the mutant 2621, suggesting the insertional inactivation of the gene. The IS element comprises 1322-bp long, flanked by 19-bp inverted terminal repeats (ITR), and generated a 6-bp target duplication (TD). Two open reading frames (ORFs) were found in the IS element. The deduced aa sequences of large and small ORFs show homology to a putative transposase found in IS4 of Escherichia coli (Ec) and to a resolvase found in ISXc5 of Xanthomonas campestris (Xc), respectively. This is the first discovery of IS element in deinobacteria, and the IS element was designated IS2621. PMID- 9370276 TI - Molecular characterization of the alpha-amylase genes of Lactobacillus plantarum A6 and Lactobacillus amylovorus reveals an unusual 3' end structure with direct tandem repeats and suggests a common evolutionary origin. AB - The alpha-amylase gene (amyA) of Lactobacillus plantarum A6 was isolated from the genome by polymerase chain reaction with degenerated oligonucleotides, synthesized according to the tryptic peptide amino acid sequences of the purified enzyme. Nucleic acid sequence analysis revealed one open reading frame of 2739 bp encoding a 913 amino acid protein. The amylase appears to be divided into two equal parts. The N-terminal part has the typical characteristics of the well known alpha-amylase family (65% identity with the alpha-amylase of Bacillus subtilis and 97% identity with the partial sequence available for the alpha amylase of Lactobacillus amylovorus). The C-terminal part displays a fairly unusual structure. It consists of four direct tandem repeated sequences of 104 amino acids sharing 100% similarity. The complete nucleotide sequence of the alpha-amylase gene of L. amylovorus was also determined. An open reading frame of 2862 bp encoding a 954 amino acid protein was identified. Perfect homology between the two amyA genes was observed in the N-terminal region. The C-terminal part of L. amylovorus alpha-amylase also included tandem repeat units but striking differences were observed: (i) the addition of one repeat unit; (ii) a shorter, 91 amino acid repetition unit. These structural homologies suggest that both genes have a common ancestor and may have evolved independently by duplication with subsequent recombination and mutation. PMID- 9370275 TI - Cloning and chromosome mapping of the feline genes p21WAF1 and p27Kip1. AB - For investigation of the relation of cell cycle regulation with tumorigenesis in cats, we carried out molecular cloning of feline p21WAF1 and p27Kip1 cDNAs and chromosomal mapping of these genes on the cat genome. The feline p21WAF1 cDNA clone obtained in this study encoded 164 amino acids (aa) showing 83.5% and 76.8% sequence similarity with those of the human and mouse counterparts, respectively. The cat p27Kip1 cDNA clone isolated here encoded 198 aa, showing sequence similarities of 93.4% and 90.4% with its human and mouse counterparts, respectively. Using a panel of feline x rodent somatic cell hybrids, the feline CDKN1A (p21WAF1) and CDKN1B (p27Kip1) loci were assigned to feline chromosomes B2 and B4, respectively. Southern-blot analyses of 17 feline spontaneous leukemia and lymphoma cases using these cDNAs as probes did not reveal any rearrangements in either the p21WAF1 or the p27Kip1 gene. RT-PCR/SSCP (single strand conformation polymorphism) analysis of p27Kip1 cDNA did not uncover any amino acid substitutions in the 10 feline leukemia and lymphoma cases that were examined. PMID- 9370277 TI - Identification of a functional CT-element in the Phytophthora infestans piypt1 gene promoter. AB - CT-rich sequences of incompletely characterized function have been found in the gene promoter regions of many organisms, fungi and members of the genus Phytophthora prominently among them. We describe here an in vitro analysis of CT element function in regulating transcription of the Phytophthora infestans piypt1 gene, a gene that encodes a monomeric G-protein believed to be involved in regulation of vesicle transport (Chen and Roxby (1996) Gene 181, 89-94). The results of the promoter analysis indicate that a 17-bp CT-element lying close to the transcription start point of this gene is important in determining the frequency of transcription initiation. Competition experiments suggest that transcription factors bind to the CT element. A subregion lying at the 5'-end of the CT-element resembles an Inr element, a type of CT-rich transcription regulator first discovered in some mammalian genes. This Inr-like subregion appears to be more important in the interactions leading to transcription initiation than more downstream regions within this CT-element. Two proteins, of 37 and 45 kDa, respectively, that bind to the CT-element and are presumed to be transcription factors were detected in P. infestans nuclear extracts by southwestern blotting. PMID- 9370278 TI - Isocitrate lyase localisation in Saccharomyces cerevisiae cells. AB - The isocitrate lyase from Saccharomyces cerevisiae was only located in the cell cytoplasm. This protein was found not to be associated with cell organelles, even under growth conditions that induce peroxisome proliferation. This conclusion is supported by experiments carried out by damaging the protoplast plasma membrane with DEAE-dextran, by differential centrifugation of osmotically lysed protoplast and by using the green fluorescent protein (GFP) of Aequorea victoria as a reporter fusion tag to localise the subcellular compartment to which isocitrate lyase is targeted. PMID- 9370279 TI - Codon usage and nucleotide composition in Coxiella burnetii. AB - Coxiella burnetii, the causative agent of Q fever, is an obligate intracellular bacterium. With the development of molecular biology techniques, there have been increasing efforts on gene cloning and other genetic analyses of this organism. In this report, we tabulate the codon usage (CU) and nucleotide (nt) co occurrence in C. burnetii, based on available nt sequence data. The average G+C content of the C. burnetii genome is 42.4%, where the G+C content is 42.7% for the chromosome and 38.7% for the plasmid. In comparison to Escherichia coli, there is biased CU. Some codons are frequently used in C. burnetii, but rarely used in E. coli and vice versa. Plasmid genes prefer A or T at the first or third position of a codon. However, TAA remains the most used stop codon. In the AT rich DNA of C. burnetii, A or T tend to occur together, forming A or T tracks. PMID- 9370280 TI - Isolation and characterization of the droPIK57 gene encoding a new regulatory subunit of phosphatidylinositol 3-kinase from Drosophila melanogaster. AB - Mammalian phosphatidylinositol 3-kinase (PI 3-kinase) plays an important role in the regulation of various cellular, receptor tyrosine kinase-mediated processes, such as mitogenesis and transformation. PI 3-kinase is composed of a 110-kDa catalytic subunit and a regulatory subunit of 85 kDa or 55 kDa. We have cloned a gene for a regulatory subunit from Drosophila melanogaster, named droPIK57, from head-specific cDNA libraries. The droPIK57 gene encodes a protein containing two SH2 domains with significant sequence homology to those in p85 and p55. Like the p55 subunits, DroPIK57 is missing the SH3 domain and the bcr homology region of the p85 subunit. The short N-terminus as well as the C-terminus of the DroPIK57 protein show no identity to the known PI 3-kinase subunits, suggesting that it is a new member in the family of regulatory subunits. In-situ hybridization and Northern blot analysis indicate a widespread function of this gene during embryogenesis and in the CNS. PMID- 9370281 TI - Sp1 protein contributes to airway-specific rat MUC 2 mucin gene transcription. AB - We have shown increases in the abundance of airway mucin mRNA during the pathogenesis of chronic obstructive pulmonary disease in rat models (Jany et al., 1991) and now seek to determine the underlying mechanisms. As transcriptional modulation may be involved, we provide here a functional analysis of the 5' flanking region of a rat mucin gene (MUC 2). Using deletion mutants to bp -859, we constructed expression cassettes in CAT vectors and transfected them into two MUC 2-expressing cell lines, SPOC 1, a rat airway epithelial cell line and IEC-6, a rat intestinal epithelial cell line, and into one MUC 2 non-expressing cell line, FR, a rat skin fibroblast cell line. Results indicated that nucleotides -59 to -40 mediated high level expression in SPOC 1, but not in the other cells. Used as a probe in gel shift assays, fragment -59/-40 formed complexes of differing mobilities when incubated with nuclear protein extracts from the three cell types. Mutation of the putative Sp1 binding site in the probe sequence interfered with protein binding in all three cell types, but anti-Sp1 antibody supershifted a band formed only by airway cell extracts. A model of airway cell-specific MUC 2 transcription is proposed. PMID- 9370282 TI - Modification of the mouse mitochondrial genome by insertion of an exogenous gene. AB - Using homologous recombination in yeast we have inserted a synthetic gene encoding human ornithine transcarbamylase (sOTC), designed to allow mitochondrial (mt) translation, into the mouse mt genome. Modification of the mt genome was facilitated by its cloning into a yeast centromeric plasmid. The sOTC gene was initially flanked by 25 bp of the mt tRNA(His) gene at its 5' end and by 23 bp of the mt tRNA(Ser (AGY)) gene at its 3' end (Wheeler et al., 1996). In order to achieve homologous recombination the flanking homology was subsequently extended to 525 and 362 bp by the polymerase chain reaction (PCR). The sOTC gene was thus inserted into the cloned mt genome at a unique location between the tRNA(His) and tRNA(Ser (AGY)) genes. Positioning of the sOTC gene between these normally contiguous tRNA genes should allow its processing from the mt polycistronic transcript. The ability to modify the mammalian mt genome in this way is a valuable step towards a functional analysis of mt genetic mechanisms and possibly also towards a gene therapy approach for mt disorders. PMID- 9370283 TI - Cloning and expression of the red visual pigment gene of goat (Capra hircus). AB - We have cloned and sequenced the red opsin gene, rCh, of goat (Capra hircus). When rCh is expressed in cultured cells and reconstituted with 11-cis retinal, the resulting visual pigment has a wavelength of maximal absorption (lambda max) of 553 nm. This result and the deduced aa sequence of the goat red opsin suggest that the lambda max values of the red pigments of goat and human are based mainly on Y277 and T285. The slightly lower lambda max value of the red pigment in goat than in human (approximately 560 nm) can be explained by a single aa difference between the goat (A180) and human (S180) red pigments. PMID- 9370284 TI - Cloning, sequencing and expression of the gene encoding elongation factor P in the amino-acid producer Brevibacterium lactofermentum (Corynebacterium glutamicum ATCC 13869). AB - The Brevibacterium lactofermentum EF-P gene, encoding the elongation factor protein P, was cloned and sequenced. According to DNA sequence analysis of this gene, the B. lactofermentum EF-P protein consists of 187 amino acids with a calculated molecular weight of 20,584. Southern hybridization of an internal fragment of the EF-P gene from B. lactofermentum with chromosomal DNAs from different microorganisms reveals that it is a unique gene product in B. lactofermentum and Corynebacterium glutamicum. The EF-P gene was expressed in E. coli using the T7 expression system and the calculated molecular weight of the expressed protein was 23,000. Disruption experiments using an internal fragment of the EF-P gene or a disrupted EF-P gene in suicide plasmids always failed, suggesting that the gene is needed for cell viability. PMID- 9370285 TI - Serine/threonine phosphatases of the pufferfish, Fugu rubripes. AB - The compact genome of the Japanese pufferfish, Fugu rubripes, about 7.5 times smaller than the human genome, facilitates the isolation of vertebrate genes. We have used this genome to isolate and characterize members of the vertebrate serine/threonine protein phosphatase gene family. Our data reveal the presence of two isoforms of PP2A, alpha and beta, and PPX, as previously found in mammals. PMID- 9370286 TI - Unique gene organization: alternative splicing in Drosophila produces two structurally unrelated proteins. AB - The Ub80 gene in eukaryotes produces a ubiquitin fusion protein in which ubiquitin is fused in frame to a tail protein (Redman and Rechsteiner, 1988; Finley et al., 1989; Barrio et al., 1994). The tail protein is incorporated into the ribosome, and ubiquitin is thought to act as a chaperone. The DUb80 gene of Drosophila melanogaster was cloned by Barrio et al. (1994) and contains a 5' untranslated exon, followed by a large intron and then the first coding exon. We report that the large intron of DUb80 contains an open reading frame, which produces a 259-aa protein (IP259) that is conserved in eukaryotes from yeast to mammals. Transcription of the DUb80 and IP259 mRNAs begins at the same start sites. However, alternate splicing of the primary transcript produces two structurally unrelated proteins. This is the second reported instance of two structurally unrelated proteins being produced via alternate splicing, suggesting that this form of genomic organization may be more common than previously thought. PMID- 9370287 TI - Sequence of the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Nicotiana plumbaginifolia and phylogenetic origin of the gene family. AB - A cDNA-library has been constructed from Nicotiana plumbaginifolia seedlings, and the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase (GapN, EC 1.2.1.9) was isolated by plaque hybridization using the cDNA from pea as a heterologous probe. The cDNA comprises the entire GapN coding region. A putative polyadenylation signal is identified. Phylogenetic analysis based on the deduced amino acid sequences revealed that the GapN gene family represents a separate ancient branch within the aldehyde dehydrogenase superfamily. It can be shown that the GapN gene family and other distinct branches of the superfamily have its phylogenetic origin before the separation of primary life-forms. This further demonstrates that already very early in evolution, a broad diversification of the aldehyde dehydrogenases led to the formation of the superfamily. PMID- 9370288 TI - Cloning and sequencing of the mouse cDNA encoding a phospholipid hydroperoxide glutathione peroxidase. AB - Phospholipid hydroperoxide glutathione peroxidase (PHGPx), a selenoprotein, reduces the hydroperoxides of phospholipid, cholesterol, and cholesteryl ester in biomembranes. In this study, a full-length cDNA clone encoding the PHGPx was isolated from mouse testes using a RACE (rapid amplification of cDNA ends) technique. According to sequence analysis, the cDNA encodes a polypeptide of 197 amino acids (aa) that initiates the translation at ATG(145-147) and contains an inframe TGA selenocysteine codon. It also has selenocysteine insertion sequences in the 3'-UTR that are involved in the insertion of selenocysteine at an opal codon. Moreover, the mouse PHGPx contains the active-site residues Gln108 and Trp163 that interact with selenocysteine, and the N-terminal 27-aa residues that may act as a potential mitochondrial targeting signal. According to the deduced aa analysis, mouse PHGPx shares a high level of aa identity with pig (93.4%), human (92.9%), and rat (98%) PHGPxs. However, the PHGPx mRNA particularly showed a high degree of expression in testis. This suggests that the PHGPx in testis may have more than just an antioxidant function. PMID- 9370289 TI - The human RAE1 gene is a functional homologue of Schizosaccharomyces pombe rae1 gene involved in nuclear export of Poly(A)+ RNA. AB - A Schizosaccharomyces pombe temperature-sensitive mutant, rae1-1, was previously identified by us as being defective in nuclear export of Poly(A)+ RNA when grown at restrictive temperature. Here, we report the isolation of the human homologue of the S. pombe rae1 gene. The RAE1 genes are highly conserved in evolution in both structure and function. The human RAE1 cDNA, when expressed from the CMV promoter, can suppress partially the temperature sensitivity of the rae1-1 mutant. This is also reflected by increased Poly(A)+ RNA export at a restrictive temperature. An epitope tagged human Rae1p localizes to both the nucleus and the cytoplasm in transiently transfected HeLa cells. We discuss the potential role of Rae1p in nuclear cytoplasmic trafficking in yeast and higher eukaryotic cells. PMID- 9370290 TI - Phenotype of recombinant Trypanosoma cruzi which overexpress elongation factor 1 gamma: possible involvement of EF-1gamma GST-like domain in the resistance to clomipramine. AB - In previous studies, molecular and immunological approaches have been used to characterize the Trypansosoma cruzi elongation factor 1gamma (TcEF-1gamma). A primary sequence homology search revealed that the TcEF-1gamma N-terminal domain showed significant homology to glutathione S-transferases (GSTs). Although studies have suggested the involvement of EF-1gamma in the protein synthesis machinery, the exact function of this protein, particularly the role of its GST like domain, is not fully understood. Therefore, we have used the protozoan parasite T. cruzi, as a recipient for a shuttle vector which allows overexpression of TcEF-1gamma in order to gain insight into its biological function. The growth of parasites which overexpress TcEF-1gamma and control cells was equally sensitive to inhibition by nifurtimox and benznidazole, which exert a trypanocidal activity through the production of free radicals. In contrast, a strong resistance of transformed organisms to the tricyclic antidepressant drug, clomipramine, a lipophilic compound, was observed, whereas control cells were highly sensitive. Our findings suggest that TcEF-1gamma participates in the detoxification of lipophilic compounds probably by conjugation with glutathione through its GST-like domain. To our knowledge, this is the first report showing that the eukaryotic EF-1gamma GST conserved enzymatic model could play a role in drug resistance. Furthermore, these results reinforce the notion that the aggressiveness of certain tumours could in part be linked to overexpression of EF 1gamma. They also raise a central question regarding the GST as target for chemotherapeutic drugs in cancer research. PMID- 9370291 TI - Isolation of human and mouse HMG2a cDNAs: evidence for an HMG2a-specific 3' untranslated region. AB - We have isolated cDNAs of the human gene for high mobility group protein HMG2a, using the method of direct cDNA selection. The gene maps to chromosome band Xq28, and is located within 40 kb from marker DXS1684, at a distance of 5.4 Mb from the telomere. The deduced human HMG2a protein sequence has a length of 199 amino acids and is 97% identical to the sequence of chicken HMG2a. The 3' untranslated regions of the HMG2a gene in both species are highly homologous (87% identical nucleotides), and are even more conserved than the coding sequences (84% identical nucleotides). In addition, a partial cDNA sequence of the putative HMG2a gene from mouse was identified. The 3' untranslated regions from human and mouse are 90% identical. We conclude that the 3' untranslated sequences have been under strong selective pressure during evolution. Whereas expression of the chicken HMG2a gene has previously been demonstrated in liver of newly hatched chicken, the human HMG2a gene is transcribed mainly in placenta. PMID- 9370292 TI - Xenopus HDm, a maternally expressed histone deacetylase, belongs to an ancient family of acetyl-metabolizing enzymes. AB - Modification of core histones can alter chromatin structure, facilitating the activation and repression of genes. A key example is the acetylation of N terminal lysines of the core histones. Recently, the mammalian histone deacetylase HD1 was cloned from Jurkat T cells, and shown to be 60% identical to the yeast global gene regulator Rpd3 (Taunton et al., 1996). Here we report the cloning of HDm, a maternally expressed putative deposition histone deacetylase from Xenopus laevis. Comparison of the amino acid sequences of histone deacetylases from diverse eukaryotes shows high levels of identity within a putative enzyme core region. Further alignment with other types of protein: acetoin-utilizing enzymes from eubacteria; acetylpolyamine hydrolases from mycoplasma and cyanobacteria; and a protein of unknown function from an archaebacterium, reveals an apparently conserved core, and suggests that histone deacetylases belong to an ancient family of enzymes with related functions. PMID- 9370293 TI - Leishmania braziliensis, molecular characterization of an elongation factor 1alpha gene. AB - The elongation factor EF-1alpha is one of the most studied components of the translation machinery owing to its abundance and possible role in other cellular functions. EF-1alpha mediates the correct coupling of the aminoacyl-tRNA on the A site of the ribosome in a GTP-dependent reaction. We have previously described an EF-1alpha DNA sequence in Leishmania amazonensis, pLEF11 (accession No. M92653), using PCR. In this paper we describe the DNA sequence and genomic organization of L. braziliensis EF-1alpha gene. Southern blot analysis revealed that EF-1alpha is organized as a 2 kb tandem repeat. The pLEF11 probe recognized a 1.8 kb mRNA from promastigotes in Northern blots. A clone containing the first copy and a half of the EF-1alpha tandem repeat was isolated by screening a L. braziliensis genomic library. Southern blot analysis showed that the isolated clone (lambda2.2) presented the same hybridization profile as that of a genomic blot. The partial sequencing of clone lambda2.2 spans 2959 nucleotides in length, which has two open reading frames separated by a putative non-coding region. The nucleotide and the predicted peptide sequence of the first coding region presented approximately 80% identity with other eukaryotic EF-1alpha genes. The sequence also displayed the four consensus motifs corresponding to the GTP-binding site (G1, G2, G3 and G4). Computer analysis of the sequence of both coding regions revealed three divergent nucleotides, which generated two changes at the amino acid level. One was found to be located in the G2 domain. The non-coding region of the EF-1alpha gene sequence showed potential regulatory elements such as polypyrimidine tracks, chi-homologous sequences and stem-loop forming sequences. PMID- 9370294 TI - A genetic selection for isolating cDNAs encoding secreted proteins. AB - We describe a simple, rapid technique for simultaneously isolating large numbers of cDNAs encoding secreted proteins. The technique makes use of a facile genetic selection performed in a strain of Saccharomyces cerevisiae deleted for its endogenous invertase gene. A cDNA cloning vector which carries a modified invertase gene lacking its leader sequence is used in conjunction with this strain. Heterologous secreted genes fused appropriately upstream of this defective invertase provide the necessary signals to restore secretion, allowing the yeast to grow on sugars such as sucrose or raffinose. This microbial growth selection facilitates scanning cDNA libraries containing millions of clones, enabling the wholesale identification of novel secreted proteins without the need for specific bioassays. The technique is similar to one previously described (Klein et al. (1996) Proc. Natl. Acad. Sci. USA 93, 7108-7113). We describe results using a cDNA library derived from activated human peripheral blood mononuclear cells (PBMC). Genes identified from this library encoded signal sequences of proteins of diverse structure, function, and cellular location such as cytokines, type 1 and type 2 transmembrane proteins, and proteins found in intracellular organelles. In addition, a number of novel secreted proteins were identified, including a chemokine and a novel G-protein-coupled receptor. Since signal sequences possess features conserved throughout evolution, the procedure can be used to isolate genes encoding secreted proteins from both eukaryotes and prokaryotes. PMID- 9370295 TI - Sequence and functional analysis of the gene encoding Vibrio cholerae cAMP receptor protein. AB - We describe here the cloning, nucleotide sequence, and functional expression of the crp gene of Vibrio cholerae (Vc) encoding the cyclic AMP receptor protein (CRP). The Vc crp gene shows 81% identity with the crp gene from Escherichia coli (Ec) and its deduced amino acid sequence shows 95% identity with the Ec protein. When expressed from inducible promoters, the cloned Vc gene produced an approximately 20-kDa protein which complemented the carbohydrate-negative and growth-defective phenotypes of both Ec and Vc crp mutants. In the Vc crp mutant, the cloned crp gene also restored the normal repression of ToxR-regulated virulence genes which occurs under certain environmental conditions. PMID- 9370296 TI - Upregulation of a novel gene by freezing exposure in the freeze-tolerant wood frog (Rana sylvatica). AB - A novel gene responsive to freezing exposure was identified among five cDNA clones obtained through differential screening of a cDNA library constructed from liver of frozen wood frogs. The cDNA sequence of this gene, cloned in the recombinant plasmid, pBfFR14, showed no homology to any genes available in the Genbank database. The clone, designated as Fr10, carried a 457 bp cDNA sequence and contained a single open reading frame that could potentially encode a small protein of 90 amino acids with a molecular weight of about 10 kDa, named FR10. The putative protein contained a highly hydrophobic N-terminal region (21 residues) that carries a potential nuclear exporting signal (NES) sequence, LALVVLVIAISGL, similar to the NES found in PKI, an inhibitor of protein kinase A (PKA). A single mRNA transcript with a size of 550 nt was detected when the insert of the pBfFR14 was used as a probe against the Northern blot containing total RNA isolated from wood frog organs. RNA blotting analysis for gene expression in eight organs showed that transcription of the gene was highly induced by 24 h of freezing exposure at -2.5 degrees C in liver and gut, moderately elevated in heart, lung, brain and bladder but showed no change in skeletal muscle and decreased in kidney. A time-course analysis for freezing regulation of gene expression in liver showed that transcript levels were increased by 2-fold in 1 h of freezing exposure and the levels continued to increase up to 3.5-fold over the control after 24 h of freezing exposure, but had returned to control levels after 24 h thawing at 5 degrees C. Gene expression in liver was also up-regulated by whole animal dehydration at 5 degrees C but strongly down-regulated by anoxia exposure, indicating that the gene may respond to cell volume regulatory signals in vivo during natural freezing. PMID- 9370297 TI - Genomic structure of the human GT334 (EHOC-1) gene mapping to 21q22.3. AB - Several inherited diseases have been mapped to the distal tip of human chromosome 21. In our recent efforts to clone candidate genes for some of these disorders, we have assembled a cosmid and BAC contig spanning 770 kb. We have identified expressed sequences from this contig by means of a cDNA hybrid selection scheme. We present here the isolation, cDNA sequence, genomic organization, and polymorphisms analysis of one such expressed sequence, GT334, which had been identified independently and designated EHOC-1. GT334 is split into 23 exons, and spans an estimated 95 kb of genomic DNA. A pseudogene of the histone H2AZ gene has been identified, and maps within the third intron. We have identified an ORF potentially encoding a protein 1259 amino acids in length, longer than that described in the EHOC-1 gene. The GT334 gene was screened for single base pair changes using single-strand conformation polymorphism (SSCP) analysis and we have identified seven sequence variations within this gene. These polymorphisms can be used as markers in the genetic mapping of other diseases localized to this region. PMID- 9370298 TI - Gene coding for the transcription factor, SUG/proteasome, p45 is located nearly 40 kb downstream from the rat growth hormone gene. AB - About 40 kilobases (kb) downstream of the rat growth hormone gene, a gene was found to be expressed in the liver and placenta as 1.5 kb poly(A)-rich RNA. Using the genomic DNA fragment as a probe, the corresponding cDNA clone containing a 1.3 kb insert was isolated from the rat liver cDNA library. The deduced amino acid sequence having 406 residues was identical with that of the mouse transcription factor, SUG and human proteasome subunit, p45. The gene was thus identified as the rat SUG/p45 (rSUG/p45) gene. The 5' end of the gene was determined by the primer-extension analysis and the exon was noted to comprise 1409 bases. The rSUG/p45 gene, 6.0 kb in length and possessing 12 exons, started at 42.8 and ended at 36.8 kb downstream from the transcription start site of the GH gene. From exon 2 to 11, the size of each rSUG/p45 exon was identical with the corresponding exon of the 4.4 kb pig gene. Rat SUG/p45 mRNA was similarly expressed in seven different tissues and one cell line. PMID- 9370299 TI - The mouse Plk gene: structural characterization, chromosomal localization and identification of a processed Plk pseudogene. AB - The Plk gene encodes a serine/threonine protein kinase believed to be important for the normal progression of mammalian cells through the cell cycle. In this paper, we report the genomic organization of the mouse Plk gene. The mouse Plk gene encompasses 16 kb of the mouse genome and is organised into 10 exons. Based on homology with the human PLK1 promoter region, the putative mouse promoter region includes a CCAAT motif but lacks the conventional TATA motif. The proposed promoter region contains consensus binding sites for several transcriptional regulators, including Sp1 and AP2. In addition to the active copy of Plk, Plk exists as a processed pseudogene. Using RFLP analysis, we have localized the active Plk gene to mouse Chromosome 7 and the processed pseudogene to mouse Chromosome 5. Southern blot analysis of DNA from a limited number of other mammalian species suggests that the duplication is confined to the mouse. Parsimony analysis suggests that the gene duplication leading to the mouse Plk pseudogene occurred after the rat-mouse split. PMID- 9370300 TI - Cloning of mouse diastrophic dysplasia sulfate transporter gene induced during osteoblast differentiation by bone morphogenetic protein-2. AB - Although intensive studies have been directed at understanding osteoblastic differentiation, the molecular mechanisms are still unclear. In this study, we describe a cDNA that encodes a sulfate transporter that was cloned as a gene induced in osteoblast precursor cells in association with osteoblastic differentiation. Based on the fact that bone morphogenetic protein-2 (BMP-2) induces osteoblastic phenotypes in immature mouse fibroblastic C3H10T1/2 cells, we performed a subtraction hybridization between BMP-2-treated and untreated cells, and have isolated one clone (designated as st-ob for sulfate transporter in osteoblast) induced by BMP-2 that is constantly expressed in osteoblastic cells. The deduced amino acid sequence and proposed structure of st-ob are mostly identical to those of the human diastrophic dysplasia sulfate transporter gene product (DTDST). St-ob mRNA was abundantly expressed in the thymus, testis, calvaria and osteoblastic MC3T3-E1 cells, whereas its expression was faint in C3H10T1/2 cells. Expression of st-ob in C3H10T1/2 cells was increased by transforming growth factor-beta1 (TGF-beta1), retinoic acid and dexamethasone as well as BMP-2. Furthermore, BMP-2 increased sulfate incorporation in C3H10T1/2 cells about twice as high as the baseline level. Osteoblasts actively take up sulfate to synthesize proteoglycans, which are one of the major components of the extracellular matrix of bone and cartilage. The present study demonstrates that st-ob induced during osteoblastic differentiation is an important phenotype of osteoblasts for characterizing their function. PMID- 9370301 TI - Characterization of the human MANB gene encoding lysosomal alpha-D-mannosidase. AB - Genomic clones of human MANB gene encoding the lysosomal enzyme, alpha mannosidase, have been isolated, sequenced and analyzed. The human MANB gene spans approximately 22 kb and consists of 24 exons. The 5' flanking region of the gene shows a high G+C content and has two Sp1 and three AP-2 sites. Promoter analysis using deletion constructs of the 5' flanking region fused to the bacterial CAT gene showed that 150 bp of 5' sequence could drive the expression of MANB in COS 7 cells. Determination of the sequence of the 5' end of the alpha mannosidase mRNA by 5' RACE protocol showed that transcription is initiated from a cluster of sites centered -28 and -20 bp from the first in-frame ATG. These data demonstrate that, like other lysosomal enzyme genes such as those for beta glucuronidase or beta-hexosaminidase, the human MANB gene is controlled by a short 5' flanking sequence located near the initiation codon. PMID- 9370303 TI - A cassette for high-level expression in the mouse salivary glands. AB - Expression in the mouse salivary glands may be used as a model system for studies involving oral cavity delivery of gene products. Previously, sequences from the mouse Psp gene were used to build a minigene construct denoted 'Lama'. This construct was used as a cassette for expression of human factor VIII light chain in mouse saliva. However, whereas the endogenous Psp mRNA is the most abundant protein-coding transcript in the parotid glands, the Lama mRNA was expressed below 1% of the level of Psp mRNA in these glands. Here, we show that a 25-kb cosmid-derived DNA fragment (PspX25) carrying the structural gene and large flanking areas of Psp is expressed in all 14 analysed lines in the parotid glands. The average level of transgene expression was estimated to be 45% of that of the endogenous Psp gene. More importantly, it was possible to transfer PspX25's ability for high-level parotid gland expression to the Lama construct. PMID- 9370302 TI - Identification of p34cdc2 kinase from sea urchin Hemicentrotus pulcherrimus and its involvement in the phosphorylation of myosin II regulatory light chain in the metaphase extract. AB - We present here the nucleotide sequence for a cDNA clone encoding p34cdc2 from sea urchin, Hemicentrotus pulcherrimus. The obtained cDNA comprised 301 amino acid residues that contained the PSTAIRE domain to be important for binding to cyclins. Amino acid sequence similarity between this clone and other eukaryotic cdc2 sequences averaged approximately 72%. Using p13suc1-conjugated Sepharose 4B and a selective inhibitor of p34cdc2 kinase, butyrolactone I, it was first suggested that p34cdc2 kinase is involved in the phosphorylation of MRLC at both MLCK site and two PKC sites. PMID- 9370304 TI - Identification of the transcription termination site of the mouse nkx-1.2 gene: involvement of sequence-specific factors. AB - We have identified a transcription termination site in the 3' flanking region of the mouse nkx-1.2 gene. A downstream transcription regulatory element in the mouse nkx-1.2 gene was characterized by transferring its 3'-fragment into a chloramphenicol acetyl transferase (CAT) expression vector. Analysis of recombinant plasmids transfected into mouse NIH3T3 cells by CAT assay showed the possible region of regulation. There were two direct repeat structures containing poly(dG-dT) x poly(dC-dA) sequences (GT repeats) in this region. The precise location of transcription termination was mapped by nuclease S1 analysis of the transcripts from recombinant plasmids transfected into COSM6 cells. It was approximately 20 nucleotides upstream of the first GT repeat within the 5' sequences of the first element of the two direct repeats. Gel mobility shift assay and footprinting analysis demonstrated that nuclear DNA binding proteins bound specifically to the sequences where the termination occurred as well as the other sequences in the second element of the direct repeats. Southwestern analysis showed that 90-, 54-, 36- and 15-kDa nuclear proteins bound to the region of the termination. It is possible that one or more of those proteins are involved in blocking the elongation of the mouse nkx-1.2 gene transcript and then result in termination. PMID- 9370305 TI - Molecular characterization of a serine/threonine kinase in the DiGeorge minimal critical region. AB - The majority of patients with DiGeorge, velocardiofacial or conotruncal anomaly facial syndromes share a common genetic etiology, deletion of chromosomal region 22q11.2. This report describes a computational approach toward the identification and molecular characterization of a newly identified serine/threonine kinase from the minimal critical deleted region (MDGCR). A cosmid contig of the minimal critical region has been assembled and sequenced in its entirety. Database searches and computer analysis of one cosmid (111f11) for coding sequences identified two regions with high similarity to the mouse serine/threonine kinase, Tsk1. Our investigations demonstrate that one of these regions contains a testis specific gene that undergoes differential splicing, while the other region is most likely a pseudogene. Northern blot analysis and cDNA cloning demonstrate that there is alternate processing of the 3'UTR without altering the conserved kinase domains within the open reading frame. Serine/threonine kinases can play a regulatory role and have been found to be expressed during early embryogenesis. Based on its position in the MDGCR and possible function, the gene reported here is a candidate for the features seen in the 22q11 deletion syndrome. PMID- 9370306 TI - Isolation and characterization of the urease gene (URE) from the pathogenic fungus Coccidioides immitis. AB - The urease (URE)-encoding gene from Coccidioides immitis (Ci), a respiratory fungal pathogen of humans, was cloned, sequenced, chromosome-mapped and expressed. Both the genomic and cDNA sequences are reported. The transcription start point and poly(A)-addition site were confirmed. The URE gene contains eight introns and a 2517-bp ORF that translates a 839-amino-acid (aa) protein of 91.5 kDa and pI of 5.5, as deduced by computer analysis of the nucleotide sequence. The translated protein revealed eight putative N-glycosylation sites. The deduced URE showed comparable levels of homology to reported URE of the jack bean plant (Canavalia ensiformis; 71.8%) and URE of several genera of bacteria (Bp, 71.7%; Hp, 68.3%; Ka, 71.6%; Pm, 71.9%). The URE gene was mapped to chromosome III of Ci and was shown to be a single copy gene by Southern hybridization. Expression of a 1687-bp fragment of the URE gene in E. coli resulted in the production of a 63 kDa recombinant protein that was recognized in an immunoblot by antiserum raised against the Ka URE homolog. This is the first report of a fungal URE gene. PMID- 9370308 TI - Sequence analysis and expression of the polyhedrin gene of Choristoneura fumiferana cytoplasmic polyhedrosis virus (CfCPV). AB - The segmented double-stranded RNA genome of Choristoneura fumiferana cytoplasmic polyhedrosis virus (CfCPV) was extracted, polyadenylated, reverse-transcribed into cDNA and cloned. The cDNA clones that hybridized to the smallest genomic segment (segment 10) were identified, and its nucleotide sequence was determined. Genome segment 10 of CfCPV was found to be 1171 nucleotides in length with a single open reading frame in one strand capable of coding a predicted protein of 258 residues (Mr of 29,795), consistent with an apparent Mr of 30.5 kDa determined by SDS-PAGE of purified polyhedrin. Comparison of the nucleotide and amino acid sequences of the polyhedrin gene of CfCPV with those of other CPVs and with several nuclear polyhedrosis viruses revealed no particular homology. Analysis of the hydrophilic profiles and predicted secondary structures of Bombyx mori (BmCPV), Euxoa scandens (EsCPV) and CfCPV indicated the presence of seven similar regions located at the amino terminus of the polyhedrin polypeptide of the three viruses. The expression of the cloned CfCPV polyhedrin gene in Escherichia coli demonstrated that this polyhedrin has the property of self assembly, since the production of crystal-like occlusion with a well-defined crystalline lattice structure was observed. PMID- 9370307 TI - Cloning and expression of five myb-related genes from rice seed. AB - Three elements in the promoter of rice glutelin genes are important for their endosperm specific expression. One of these, an AACA motif, has been shown to be a negative regulator in non-seed tissues and has a similarity to the barley gibberellin responsive element recognized by MYB-like DNA binding proteins. A cDNA library constructed from immature rice seed was screened using two types of myb gene probes to isolate cDNA clones representing genes encoding MYB-like DNA binding proteins that may recognize the AACA motif in rice glutelin gene promoter. We obtained four cDNA clones encoding MYB-related proteins, Oryza sativa MYB (OSMYB) 1-4, using the maize C1 probe. Another myb-like clone, Osmyb5, was obtained by screening a rice seed cDNA library with probes designed to recognize the AACA-like binding domain in GAMYB and PHMYB3. RT-PCR was used to analyze Osmyb expression during rice seed development and their presence in other rice tissues, as it was not possible to detect these mRNAs by conventional Northern analysis. RT-PCR analysis showed that Osmyb2, Osmyb3 and Osmyb5 genes were expressed in all tissues examined. In seed, the mRNA levels of Osmyb1 and Osmyb4 genes reached a maximum at 14 days after flowering (DAF), suggesting that these genes may play a role in seed maturation. As Osmyb5 exhibits a high similarity to the regions in both GAMYB and PHMYB3, which can bind to the AACA motif, there is a possibility that the OSMYB5 protein may bind to the AACA motif of glutelin genes. PMID- 9370309 TI - Cloning and characterization of hcKrox, a transcriptional regulator of extracellular matrix gene expression. AB - cKrox is a novel zinc finger-containing transcription factor that binds to the alpha1(I) and alpha2(I) collagen gene promoters. The gene coding for cKrox is a new member of a family of early growth response genes, that play important roles in development. In the mouse, cKrox is expressed, beginning at 9.5 days of gestation and at 10.5 days in regions destined to become skin. In adult animals, expression is predominantly in skin, one of the two major organs where type I collagen is expressed. We have isolated cDNA clones for human cKrox. Theoretical translation of the nucleic acid sequence reveals 90% conservation of amino acids between the mouse and human proteins; however, the human gene product contains a 117-amino-acid N-terminal extension. The amino acid sequences of the zinc-finger DNA binding domains of mouse and human cKrox are identical. RT-PCR analysis of human fibroblasts indicates constitutive low-level expression of cKrox which can be transiently elevated by treatment with retinoic acid. Transient transfection assays indicate that hcKrox represses transcription of the alpha1(I) procollagen promoter, and electrophoretic mobility shift assays demonstrate that hcKrox binds to both the human and murine promoter DNA. Deletion derivatives of hcKrox demonstrate transcription-activating potential that is promoter-dependent. NIH3T3 cells permanently expressing hcKrox demonstrate a threefold and 10-fold decrease in alpha1(I) procollagen and fibronectin mRNA levels, respectively, compared to control cells. Consistent with this finding, a fibronectin promoter reporter construct is repressed more than 80% by hcKrox. These data suggest that hcKrox represses collagen transcription directly, and it may function as a repressor of fibronectin and possibly other matrix genes. PMID- 9370310 TI - sn-Glycerol-3-phosphate acyltransferase from Escherichia coli. AB - This review attempts to capture the history of research involved in the understanding of lipid metabolism via investigation of the sn-glycerol-3 phosphate acyltransferase (glycerol-P acyltransferase), the first step in the synthesis of lipids in E. coli. We will review the original identification of this enzymatic activity and its subsequent characterization. The biochemical and genetic regulation of this enzyme and gene are discussed, as well as the unique structural characterization of this integral membrane protein. Future perspectives regarding the regulatory and structural aspects of this key enzyme are discussed. PMID- 9370312 TI - Mammalian mitochondrial glycerol-3-phosphate acyltransferase. AB - Glycerol-3-phosphate acyltransferase (GPAT) is the first committed, and presumed to be a rate-limiting, step in glycerophospholipid biosynthesis. There are two isoforms of GPAT, a mitochondrial and a microsomal form. Mitochondrial GPAT has recently been purified and its gene has been cloned and expressed in baculovirus infected cells. The GPAT activity was reconstituted using the purified enzyme and various phospholipids. Mitochondrial GPAT prefers saturated fatty acyl-CoA as a substrate. This preference may contribute to the observed asymmetric distribution of saturated and unsaturated fatty acids at the sn-1 and sn-2 positions of cellular glycerophospholipids. A region of homology to various acyltransferases that may be important for catalysis or fatty acyl-CoA binding is present in mitochondrial GPAT. Mitochondrial GPAT is upregulated at the transcriptional level by refeeding a high carbohydrate, fat-free diet to previously fasted mice and by insulin administration to diabetic animals, whereas microsomal GPAT activity is largely unaffected by these treatments. PMID- 9370311 TI - Glycerol-3-phosphate acyltransferase in plants. AB - Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the transfer of an acyl group from an acyl donor to the sn-1 position of glycerol 3-phosphate. The plant cell contains three types of GPAT, which are located in the chloroplasts, mitochondria and cytoplasm, respectively. The enzyme in chloroplasts is soluble and uses acyl-(acyl-carrier protein) as the acyl donor, whereas the enzymes in the mitochondria and the cytoplasm are bound to membranes and use acyl-CoA as the acyl donor. cDNAs for GPAT of chloroplasts have been cloned from several plants, and the gene for the enzyme has been cloned from Arabidopsis thaliana. The amino acid sequences deduced from the nucleotide sequences of cDNAs indicate that the product of translation is a precursor of about 460 amino acid residues, which consists of a leader sequence of about 70 amino acid residues and a mature protein of about 400 residues, with a molecular mass of about 42 kDa. Genetic engineering of the unsaturation of fatty acids has been achieved by manipulation of the cDNA for the GPAT found in chloroplasts and has allowed modification of the ability of tobacco to tolerate chilling temperatures. PMID- 9370313 TI - Dihydroxyacetone phosphate acyltransferase. AB - In this article the properties, assay, distribution, subcellular localization, deficiency in congenital peroxisomal disorders, purification and physiological functions of dihydroxyacetone phosphate acyltransferase (EC 2.3.1.42) are reviewed. PMID- 9370314 TI - Alkyl-dihydroxyacetonephosphate synthase. AB - Mammalian ether phospholipids are characterized by a glycero-ether linkage at the sn-1-position of the glycerol backbone. In humans this type of phospholipid species occurs mainly in the ethanolamine and choline phosphoglycerides comprising an estimated 15% of total phospholipids. The glycero-ether linkage is synthesized by replacement of the acyl chain in acyl-dihydroxyacetonephosphate by a long-chain alcohol that donates the oxygen for the ether linkage. Both the enzyme that forms acyl-dihydroxyacetone phosphate (see Chapter II of this volume) and the one that introduces the glycero-ether linkage. i.e. alkyl dihydroxyacetonephosphate synthase, are located in peroxisomes. The deficiency of ether phospholipids in human inborn errors of metabolism, caused by defects in peroxisome biogenesis, has clearly delineated the indispensable role of peroxisomes in ether phospholipid synthesis. The most characteristic enzyme of ether lipid synthesis is alkyl-dihydroxyacetonephosphate synthase. Its discovery and some of its properties, including mechanistic studies, have been discussed in recent reviews. This review recapitulates these findings and focuses on the new insights into the structure and properties of the enzyme that have recently been obtained resulting from the purification and subsequent cloning and expression of the cDNA encoding this peroxisomal enzyme. PMID- 9370315 TI - Phosphatidate phosphatases and diacylglycerol pyrophosphate phosphatases in Saccharomyces cerevisiae and Escherichia coli. AB - Phosphatidate phosphatase plays a major role in the synthesis of phospholipids and triacylglycerols in the yeast Saccharomyces cerevisiae. Membrane- and cytosolic-associated forms of the enzyme have been isolated and characterized. These enzymes are Mg2+-dependent and N-ethylmaleimide-sensitive. The expression of a membrane-associated form of phosphatidate phosphatase is regulated by growth phase and inositol supplementation, whereas enzyme activity is regulated by lipids, nucleotides, and by phosphorylation. Phosphatidate phosphatase is coordinately regulated with other phospholipid biosynthetic enzymes including phosphatidylserine synthase. Diacylglycerol pyrophosphate phosphatase is a novel enzyme of phospholipid metabolism which is present in S. cerevisiae, Escherichia coli, and mammalian cells. This enzyme possesses a phosphatidate phosphatase activity which is Mg2+-independent and N-ethylmaleimide-insensitive and is distinct from the Mg2+-dependent and N-ethylmaleimide-sensitive form of phosphatidate phosphatase. Genes encoding for diacylglycerol pyrophosphate phosphatase have been isolated from S. cerevisiae and E. coli. The deduced protein sequences of these genes show homology to the sequence of the mouse PAP2 (Mg2+-independent and N-ethylmaleimide-insensitive phosphatidate phosphatase) protein, especially in a novel phosphatase sequence motif. Rat liver PAP2 displays diacylglycerol pyrophosphate phosphatase activity. PMID- 9370316 TI - Phosphatidic acid phosphatase from mammalian tissues: discovery of channel-like proteins with unexpected functions. AB - Phosphatidic acid phosphatase (PAP) has long been known as a key enzyme involved in both glycerolipid biosynthesis and cellular signal transduction. The cDNA cloning of a plasma membrane-bound type 2 PAP has revealed the existence of a novel glycoprotein with six transmembrane domains. The type 2 PAP now represents an enzyme family consisting of Drosophila Wunen and rat Dri 42, which participate in germ cell migration and epithelial differentiation, respectively. Such novel functions of the type 2 PAP suggest the unexpected importance of lipids and/or their metabolic enzymes. PMID- 9370317 TI - Choline kinase from yeast. AB - Choline kinase, the initial enzyme of the CDP-choline pathway, mediates the conversion of choline to phosphorylcholine and is localized in the supernatant fraction of cells. The enzyme also catalyzes the phosphorylation of ethanolamine, functioning as the initial enzyme of the CDP-ethanolamine pathway as well. Yeast choline kinase is encoded by a single structural gene, CKI, which was cloned by the genetic complementation of the choline kinase mutation cki. The deduced sequence comprises 582 amino acid residues with a molecular mass of 66316 Da and bears local sequence similarity to various protein kinases and bacterial antibiotic phosphotransferases. The expression of yeast choline kinase is transcriptionally repressed by myo-inositol and choline in a coordinate manner with other phospholipid-synthesizing enzymes in yeast. PMID- 9370318 TI - Choline/ethanolamine kinase from mammalian tissues. PMID- 9370319 TI - CTP:phosphocholine cytidylyltransferase. AB - CTP:phosphocholine cytidylyltransferase (CCT) catalyzes the synthesis of CDP choline and is regulatory for phosphatidylcholine biosynthesis. This review focuses on recent developments in understanding the catalytic and regulatory mechanisms of this enzyme. Evidence for the nuclear localization of the enzyme is discussed, as well as evidence suggesting cytoplasmic localization. A comparison of the catalytic domains of CCTs from a wide variety of organisms is presented, highlighting a large number of completely conserved residues. Work implying a role for the conserved HXGH sequence in catalysis is described. The membrane binding domain in rat CCT has been defined, and the role of lipids in activating the enzyme is discussed. The identification of the phosphorylation domain is described, as well as approaches to understand the role of phosphorylation in enzyme activity. Other possible control mechanisms such as enzyme degradation and gene expression are presented. PMID- 9370320 TI - CTP:phosphoethanolamine cytidylyltransferase. AB - CTP:phosphoethanolamine cytidylyltransferase (ET) catalyzes the conversion of phosphoethanolamine into CDP-ethanolamine. Immunogold electron microscopy studies have demonstrated that, in hepatocytes, ET is localized predominantly in areas of the cytoplasm that are rich in rough endoplasmic reticulum (RER). Within these areas the enzyme shows a bimodal distribution between the cisternae of the RER and the cytosolic space. Studies on the substrate specificity of ET have shown that it can utilize both CTP and dCTP as substrates, but not other trinucleotides. In addition, the enzyme shows a very pronounced specificity for phosphoethanolamine. Under most conditions ET contributes significantly to the overall regulation of the CDP-ethanolamine pathway. Reversible binding of the enzyme to the endoplasmic reticulum could potentially play a key-role in metabolic channeling of phosphatidylethanolamine synthesis. ET has been purified from rat liver. Convincing evidence has been provided that ET and CTP:phosphocholine cytidylyltransferase (CT), the analogous enzyme in the CDP choline pathway, are separate activities that reside on different proteins. The gene coding for yeast ET has been cloned. The deduced amino acid sequence contained a region in the N-terminal half with significant similarities to the conserved catalytic domain of both yeast and rat CT. The human cDNA for ET was also cloned recently. The predicted amino acid sequence of human ET shows a high degree of similarity (36% identity) to that of yeast ET, but the human protein is longer than the yeast protein, especially at the C-terminal region. Interestingly, both yeast and human ET have a large repetitive sequence in their N-terminal and C-terminal half. PMID- 9370321 TI - CDP-choline:1,2-diacylglycerol cholinephosphotransferase. AB - Cholinephosphotransferase transfers a phosphocholine moiety from CDP-choline to diacylglycerol thus forming phosphatidylcholine (PtdCho) and CMP. This reaction defines the ultimate step in the Kennedy pathway for the genesis of de novo synthesized PtdCho. Hence, the intracellular location of cholinephosphotransferase identifies both the site from which de novo synthesized PtdCho is transported to other organelles and the site from which it is assembled with proteins and other lipids for secretion from the cell during the generation of lung surfactant, lipoproteins, and bile. Most subcellular fractionation studies observed the majority of cholinephosphotransferase activity in the endoplasmic reticulum, although the method of subcellular fractionation was found to grossly affect these results with activity alternately dispersed within Golgi, nuclear, and mitochondrial fractions. Coupling subcellular fractionation results with immunofluorescence or electron microscopy studies would resolve the issue of the site of PtdCho synthesis. However, antibodies have yet to be generated to cholinephosphotransferase since its integral membrane-bound nature has prevented its purification from any source and a mammalian cholinephosphotransferase cDNA has also yet to be isolated. However, cholinephosphotransferase genes have recently been isolated from the yeast Saccharomyces cerevisiae. Structure/function analysis of the S. cerevisiae cholinephosphotransferase has allowed for an in depth molecular examination resulting in the identification of the catalytic site. In addition, this analysis has generated the predicted amino acid data necessary to produce antibodies to pursue the site of PtdCho synthesis in this organism, as well as to provide information that should allow for the isolation of mammalian cholinephosphotransferase cDNA(s). PMID- 9370322 TI - CDP-choline:alkylacetylglycerol cholinephosphotransferase catalyzes the final step in the de novo synthesis of platelet-activating factor. AB - Platelet-activating factor (PAF) can be synthesized de novo or by a remodeling mechanism involving the sn-2 acyl moiety of alkylacylglycerophosphocholines, a membrane-bound precursor. The final step in the de novo pathway is catalyzed by a dithiothreitol-insensitive cholinephosphotransferase that utilizes 1-alkyl-2 acetyl-sn-glycerol and CDP-choline as substrates. This article reviews various studies concerning the occurrence, assay, subcellular location, biochemical properties, substrate specificity, and regulatory controls of the PAF-related cholinephosphotransferase. Alkylacetylglycerol cholinephosphotransferase, which is located on the cytoplasmic surface of the endoplasmic reticulum, is widely distributed among mammalian tissues. Both the alkyl and acyl analogs of radylacetylglycerol are utilized at equivalent rates. Optimal enzyme activity occurs at pH 8.0 and Mg2+ is required, whereas calcium, deoxycholate, ethanol, and centrophenoxine are inhibitory. Formation of CDP-choline by cytidylyltransferase appears to play a crucial role in the regulation of PAF produced via the cholinephosphotransferase route. Significant differences exist in the behavior of the cholinephosphotransferase activities responsible for the synthesis of PAF and phosphatidylcholine. However, neither enzyme activity has been purified or cloned and, therefore, it is unknown whether a single or two separate proteins are responsible for the observed catalytic activities that form these two distinctly different classes of phospholipids. PMID- 9370323 TI - CDP-ethanolamine:1,2-diacylglycerol ethanolaminephosphotransferase. AB - Ethanolaminephosphotransferase catalyzes the final step of the CDP-ethanolamine pathway for the de novo synthesis of phosphatidylethanolamine (PtdEtn) via transfer of a phosphoethanolamine moiety from CDP-ethanolamine to diacylglycerol for the formation of PtdEtn and CMP. Ethanolaminephosphotransferase is an integral membrane-bound enzyme whose intracellular location defines the site of PtdEtn synthesis by the CDP-ethanolamine pathway. Subcellular fractionation experiments have yet to resolve the precise subcellular location of ethanolaminephosphotransferase, although it is routinely associated with the microsomal fraction. Ethanolaminephosphotransferase has yet to be purified from any source and its cDNA has not been isolated from any mammalian source, thus preventing the generation of antibodies necessary to directly examine its intracellular location through immunofluorescence or electron microscopy approaches. An ethanolaminephosphotransferase gene has recently been isolated from the yeast Saccharomyces cerevisiae and structure/function analyses of the encoded enzyme identified several important characteristics including the catalytic site. The predicted amino acid sequence of the S. cerevisiae ethanolaminephosphotransferase gene should allow for the generation of antibodies required to directly define the site of PtdEtn synthesis in this organism, and it has provided the necessary information to pursue the isolation of a mammalian cDNA. PMID- 9370324 TI - Acyl-GPC and alkenyl/alkyl-GPC:acyl-CoA acyltransferases. AB - In mammalian tissues, phosphatidylcholine, or 1,2-diacyl-glycerophosphocholine (GPC), is the most abundant form of choline-containing phospholipids. In some electrically active tissues, a significant portion of the choline-containing phospholipids is 1-alkenyl-2-acyl-GPC (plasmenylcholine). The 1-alkyl-2-acyl-GPC is found in significant amounts in circulating cells such as neutrophils and macrophages but in low amounts in other tissues. Structural studies of phosphatidylcholine indicate that there is an asymmetric distribution of acyl groups on the molecule. Saturated fatty acids are usually esterified at the sn-1 position of the glycerol backbone, whereas unsaturated fatty acids are esterified at the sn-2 position. Similarly, unsaturated acyl groups are usually found in the sn-2 position of plasmenylcholine. The remodelling of the sn-2 acyl group in phosphatidylcholine by the deacylation-reacylation process has been demonstrated in a number of tissues. Phospholipase A2 is responsible for the hydrolysis of the acyl group at the sn-2 position, whereas 1-acyl-GPC:acyl-CoA acyltransferase is responsible for the reacylation reaction. The acyltransferase is located in the microsomal fraction and displays specificity towards the polyunsaturated acyl groups. The enzyme can be solubilized by detergent, but the enzyme activity in soluble form is difficult to maintain. The acyltransferase for the reacylation of 1-alkenyl-GPC is also located in the microsomal fraction and is somewhat specific towards polyunsaturated acyl groups. In guinea pig heart mitochondria, however, a new form of 1-alkenyl-GPC acyltransferase was identified which appeared to be different from the microsomal form. The acyltransferase for the acylation of 1 alkyl-GPC into platelet-activating factor has been studied in several tissues including human neutrophils. At present, the contribution of the acyltransferase in attaining the observed molecular composition of the choline-containing phospholipids in the tissue has not been defined. We postulate that the intrinsic acyl-CoA specificity of the acyltransferase, the flux of 1-acyl-GPC, 1-alkenyl GPC and 1-alkyl-GPC, as well as the pool size of acyl-CoA are major factors in producing the final composition of the molecular species of the choline containing phospholipids. PMID- 9370325 TI - The phospholipid methyltransferases in yeast. AB - In fungal microorganisms including fission yeast, Schizosaccharomyces pombe and baker's yeast, Saccharomyces cerevisiae, two enzymes are required to catalyze the synthesis of phosphatidylcholine (PC) from phosphatidylethanolamine (PE). The genes encoding the class I and class II phospholipid N-methyltransferases (PLMTs) have been cloned from both yeasts. The class II PLMTs catalyze the first methylation step from PE to phosphatidyl-monomethylethanolamine (PMME). Representatives of the class II type enzymes have been isolated only from yeast and the amino acid sequence of these enzymes contain regions of internal duplication. The class I PLMTs catalyze the last two methylation steps from PMME to PC. The class I PLMTs from both yeasts are homologous to the products of the phosphatidylethanolamine methyltransferase (PEMT) genes isolated from mouse and rat (described in the article by Vance et al. in this volume). Like the mammalian PEMT gene products, the S. cerevisiae class I enzyme can catalyze all three methylation steps to PC biosynthesis. S. cerevisiae strains, in which either the class II or class I enzyme is deleted, grow slowly in the absence of choline and exhibit low levels of PC. However, in S. pombe, mutants lacking either one of the two PLMTs are choline auxotrophs. Thus, both enzymes are required in S. pombe for maximal growth in the absence of exogenous choline. The S. cerevisiae methyltransferase genes are regulated at the level of transcription in response to the soluble precursors, inositol and choline as well as to growth phase. The mechanism of regulation of the S. pombe methyltransferases is not yet understood but appears to occur post-transcriptionally in response to choline availability. In addition, the S. pombe PLMT genes are regulated transcriptionally in response to growth phase. PMID- 9370326 TI - Phosphatidylethanolamine N-methyltransferase from liver. AB - Phosphatidylethanolamine N-methyltransferase (PEMT) converts phosphatidylethanolamine to phosphatidylcholine. Most PEMT activity (PEMT1) is associated with endoplasmic reticulum. A second form of the enzyme (PEMT2) has been localized to the mitochondria-associated membrane. PEMT2 is a 22.5-kDa protein that has been purified from rat liver. The rat liver PEMT2 cDNA and the murine PEMT gene have been cloned and characterized. The PEMT gene encodes both forms of the enzyme. Deletion of the PEMT gene eliminates all activity in liver that converts phosphatidylethanolamine to phosphatidylcholine. The activity of PEMT is regulated by supply of the substrates, phosphatidylethanolamine and S adenosylmethionine, and by the product S-adenosylhomocysteine. The expression of the gene is regulated during development and by the supply of choline in the diet. There is reciprocal regulation of the Kennedy pathway for phosphatidylcholine biosynthesis (via CDP-choline) and phosphatidylethanolamine N methyltransferase. Several experimental approaches suggest that this enzyme might play a role in regulation of hepatocyte growth and cell division. PMID- 9370327 TI - Phosphatidylserine synthase I and II of mammalian cells. AB - Phosphatidylserine (PtdSer) in mammalian cells is synthesized through an exchange of free L-serine for the base moiety of pre-existing phospholipids. Studies on PtdSer biosynthesis in Chinese hamster ovary (CHO) cells have suggested that the serine base-exchange is catalyzed by at least two different enzymes; one, named PtdSer synthase I (PSS I), uses phosphatidylcholine (PtdCho) and possibly phosphatidylethanolamine (PtdEtn) as phosphatidyl donors for the serine base exchange, and the other, named PtdSer synthase II (PSS II), uses PtdEtn but not PtdCho as a phosphatidyl donor. Recently, cDNAs of the PSS I and II have been isolated from CHO-K1 cells. This review will briefly describe the current understanding of PtdSer synthases of mammalian cells, mainly CHO cells. PMID- 9370328 TI - CDP-diacylglycerol synthase of microorganisms. AB - The synthesis and utilization of CDP-diacylglycerol in mammalian cells was demonstrated over 35 years ago when initial studies were carried out. However, CDP-diacylglycerol synthases and the genes encoding these enzymes have been studied in the greatest detail in Escherichia coli and Saccharomyces cerevisiae. The involvement of CDP-diacylglycerol in regulation of phospholipid metabolism has recently been demonstrated in Saccharomyces cerevisiae, and evidence now exists from studies in Drosophila that this liponucleotide may be important in regulation of lipid-dependent signal transduction processes. The vast amount of biochemical and genetic information on the synthases from microorganisms has led to the cloning of genes that encode CDP-diacylglycerol synthases from somatic cells. The combination of information on these synthases from all organisms will lead to a clearer understanding of the role CDP-diacylglycerol plays in cellular processes. PMID- 9370329 TI - CDP-diacylglycerol synthase from mammalian tissues. AB - CDP-diacylglycerol resides at the branch point of glycerolipid biosynthesis as precursor of both the phosphoinositides and phosphatidylglycerol. The discovery of the phosphoinositide signal transduction pathway and the recognition of its prominent role in intracellular communication has focused new attention on CDP diacylglycerol synthase. As a rate-limiting step in this pathway, it is a likely target for regulation. Exploration of this possibility will be facilitated by the recent cloning of mammalian CDP-DAG synthase. PMID- 9370330 TI - Phosphatidylinositol synthase from yeast. AB - PI is an important precursor for polyphosphoinositides and some sphingolipids and is also involved in the glycolipid anchoring of plasma membrane proteins. This lipid is synthesized from CDP-diacylglycerol and myo-inositol by PI synthase, an enzyme localized in the outer mitochondrial membranes and microsomes in yeast. PI synthase was highly purified from yeast microsomes after solubilization with Triton X-100. The activity is dependent on Mn2+ or Mg2+ and Triton X-100. The reaction follows a sequential Bi-Bi mechanism with binding to CDP-diacylglycerol before myo-inositol and releasing PI prior to CMP. Unlike most of the yeast phospholipid-synthesizing enzymes, PI synthase is a constitutive enzyme. Its expression is insensitive to the addition of myo-inositol and choline to culture medium or the transition of growth phase. The primary translate deduced from the encoding gene, PIS, comprises 220 amino acid residues with a calculated molecular mass of 23,613. The sequence contains several hydrophobic regions and resembles that of the human enzyme. The sequence also contains the local, conserved region found in enzymes catalyzing the transfer of the phosphoalcohol moiety from CDP alcohol, such as phosphatidylserine synthase, cholinephosphotransferase and phosphatidylglycerolphosphate synthase. Substitution of amino acid at position 114 from His (CAC) to Gln (CAA) results in a 200-fold increase in Km of the enzyme for myo-inositol, making cells auxotrophic for myo-inositol. Disruption of the PIS locus in the genome is lethal, indicating that PI is essential for the survival and growth of yeast cells. PMID- 9370331 TI - Phosphatidylinositol synthase from mammalian tissues. AB - Phosphatidylinositol synthase (CDP-diacylglycerol:myo-inositol 3-phosphatidyl transferase, EC 2.7.8.11) is a 24-kDa membrane-bound enzyme. It is present in all mammalian cells and is localized predominantly to the endoplasmic reticulum. The enzyme performs the last step in the de novo biosynthesis of the phospholipid phosphatidylinositol by catalyzing the condensation of CDP-diacylglycerol and myo inositol to form the products phosphatidylinositol and CMP. Phosphatidylinositol, apart from being an essential membrane phospholipid, is involved in protein membrane anchoring and is the precursor for the second messengers inositol-tri phosphate and diacylglycerol. PMID- 9370332 TI - Phosphatidylglycerophosphate synthase from yeast. AB - The phospholipid cardiolipin, or diphosphatidylglycerol, is ubiquitous in eucaryotes. It is unique in structure, subcellular localization, and potential function. Because it is found predominantly in the mitochondrial inner membrane, it is an excellent marker for mitochondrial biogenesis. Cardiolipin is required for activity of several mitochondrial enzymes and possibly also for import of proteins into the mitochondrion. To understand the role of cardiolipin in these cellular events, it is necessary to characterize the enzymes of the cardiolipin pathway, as well as the genes that control the expression of these enzymes. To date, the structural genes encoding the cardiolipin biosynthetic enzymes have not been identified in any eucaryotic organism. However, considerable information is available regarding the regulation of this pathway in yeast. The activity and regulation of the first enzyme of the pathway, CDP-diacylglycerol:sn-glycerol-3 phosphate 3-phosphatidyltransferase (phosphatidylglycerophosphate (PGP) synthase, EC 2.7.8.5), has been characterized in two evolutionarily divergent yeasts, Saccharomyces cerevisiae and Schizosaccharomyces pombe. In contrast to the second and third enzymes of the pathway, this enzyme is highly regulated, both by cross pathway control and by factors affecting mitochondrial development. PGP synthase from S. pombe (and cardiolipin synthase from S. cerevisiae) have been purified to homogeneity. The amino acid sequences of these enzymes, combined with the availability of the complete genome sequence from S. cerevisiae will simplify the cloning of these genes in the near future. PMID- 9370333 TI - Cardiolipin synthase from Escherichia coli. AB - Escherichia coli cardiolipin synthase catalyzes reversible phosphatidyl group transfer from one phosphatidylglycerol molecule to another to form cardiolipin (CL) and glycerol. The enzyme is specified by the cls gene, located at min 28.02 of the E. coli genetic map. Cells with mutations in cls have longer doubling times, tend to lose viability in the stationary phase, are more resistant to 3,4 dihydroxybutyl-1-phosphonate, and have an altered sensitivity to novobiocin. Although cls null mutants appear to lack CL synthase activity, they are still able to form trace quantities of CL. The enzyme appears to be regulated at both the genetic and enzymatic levels. CL synthase's molecular mass is 45-46 kDa, or about 8 kDa less than the polypeptide predicted by the gene sequence, suggesting that posttranslational processing occurs. CL synthase can use various polyols such as mannitol and arabitol to convert CL to the corresponding phosphatidylglycerol analog. When the amino acid sequences of four bacterial CL synthases are compared, three highly conserved regions are apparent. One of these regions contains a conserved pentapeptide sequence, RN(Q)HRK, and another has a conserved HXK sequence. These two sequences may be part of the active site. E. coli CL synthase has been studied by using a mixed micelle assay. The enzyme is inhibited by CL, the product of the reaction, and by phosphatidate. Phosphatidylethanolamine partially offsets inhibition caused by CL but not by phosphatidate. CDP-diacylglycerol does not appear to affect the activity of the purified enzyme but does stimulate the activity associated with crude membrane preparations. PMID- 9370334 TI - Cardiolipin synthase from yeast. AB - Cardiolipin synthase catalyzes the synthesis of the mitochondrial phospholipid cardiolipin. Cardiolipin synthase is a unique membrane-bound enzyme in that it utilizes two phospholipids, both insoluble in water, as substrates. Kinetic analysis suggests that the enzyme forms a ternary complex with the two lipid substrates, and that a divalent metal ion directly associates with cardiolipin synthase to form the active enzyme. While little is known about the regulation of cardiolipin synthase in yeast, activity is reduced in mutants in which the mitochondrial genome is deleted, and in mutants with defective respiratory complexes. In p0 mutants, which contain no mitochondrial DNA and are defective in the assembly of many mitochondrial membrane protein complexes, cardiolipin synthase activity is reduced by 50%. Mutants defective in respiratory complexes, particularly those incapable of cytochrome oxidase assembly, also have reduced cardiolipin synthase activity. Thus it is likely that respiration and cardiolipin formation are interdependent. The enzyme was recently purified from the budding yeast Saccharomyces cerevisiae. Enzyme activity was associated with a 25-30-kDa protein. The amino acid sequence of this protein, combined with the availability of the complete yeast genome sequence, will hopefully lead to the identification of the structural gene for this enzyme in the near future. PMID- 9370335 TI - Cardiolipin synthase from mammalian mitochondria. AB - Cardiolipin was first isolated from beef heart and was shown to contain an unusually high content of linoleic acid ester residues. Cardiolipin is found throughout the eukaryotes including animals, plants and fungi. In mammalian tissue and in yeast, cardiolipin is found exclusively in mitochondria. Mitochondrial synthesis of cardiolipin utilizes phosphatidylglycerol and CDP diacylglycerol as substrates in a reaction which requires a divalent cation (Mg2+, Mn2+ or Co2+). Cardiolipin synthase has been purified to near-homogeneity from rat liver by solubilization with Zwittergent 3-14 followed by FPLC anion exchange, gel permeation and chromatofocusing steps. Cardiolipin synthase has a molecular mass of 50 kDa, a pH optimum of 8.0, and requires added phospholipids (phosphatidylethanolamine and cardiolipin) and 4 mM Co2+ for optimal activity. Except for the effects of divalent cations and the requirement for phospholipids, little is known about the regulation of cardiolipin synthase. Cardiolipin deficiency in aging mitochondria has been linked to decreased metabolite transport across the inner membrane. Both cardiolipin levels and cardiolipin synthase activity are increased in hyperthyroidism and decreased in hypothyroidism suggesting regulation by thyroid hormone. Mammalian cardiolipin synthase has not been sequenced or cloned and its biological role in mitochondria is not yet fully understood. PMID- 9370336 TI - Phosphatidylserine synthase from bacteria. AB - This review summarizes the characteristics of two subclasses of phosphatidylserine synthases: subclass I of gram-negative bacteria and subclass II of gram-positive bacteria. Unlike other phospholipid biosynthetic enzymes, the phosphatidylserine synthases of gram-negative bacteria, the enzyme from Escherichia coli has been extensively examined and characterized, are associated with the ribosomal fraction of cell lysates. Enzymes from gram-positive bacteria are membrane-bound, and the structural gene of membrane-bound synthase of Bacillus subtilis has been cloned and used in our laboratory for replacement with the E. coli counterpart. This review discusses the possible regulatory mechanisms of phosphatidylethanolamine synthesis in E. coli, which are closely related to the subcellular localization and properties of phosphatidylserine synthase, and highlights the cross-feedback regulatory model which assumes two forms of phosphatidylserine synthase (only molecules bound with acidic phospholipids of the membrane are active in phosphatidylserine synthesis, whereas others in the cytoplasm are latent). In addition, considerations of the origin and evolution of the two vastly different subclasses of phosphatidylserine synthases of bacteria are also presented. PMID- 9370337 TI - Phosphatidylserine synthase from yeast. AB - Whereas mammalian cells produce PS by a base exchange reaction from preexisting phospholipids, yeast cells synthesize PS from CDP-diacylglycerol and serine by the PS synthase reaction. Yeast PS synthase was purified to homogeneity and shown to have a molecular mass of 23 kDa. The activity is dependent on either Mg2+ or Mn2+ and Triton X-100. The enzyme specifically transfers the phosphatidyl group from CDP-diacylglycerol or dCDP-diacylglycerol to L-serine, but not to threonine, cysteine and ethanolamine. The PSS/CHO1 gene encoding the enzyme was cloned by the complementation of the choline auxotrophic pss/cho1 mutant. The deduced protein comprises 279 amino acids with a calculated molecular mass of 30,804. The primary translate undergoes proteolytic processing to the enzymatically more active 23-kDa enzyme. The deduced amino acid sequence contains several putative membrane-spanning regions and resembles that of the Bacillus subtilis enzyme, but not those of the E. coli and Haemophilus influenzae enzymes. The sequence also contains the local, conserved region found in enzymes catalyzing the transfer of the phosphoalcohol moiety from CDP-alcohol, such as PI synthase, cholinephosphotransferase and phosphatidylglycerolphosphate synthase. The activity of PS synthase is maximal in the exponential phase, but decreases when cells enter the stationary phase. The enzyme is phosphorylated at a single serine residue by cyclic AMP-dependent protein kinase with a 60-70% decrease in enzymatic activity, but the primary translation product is not phosphorylated. PS synthase is inhibited by CTP, probably due to the chelation of the divalent cations, Mg2+ and Mn2+, and also by sphingoid bases, such as sphinganine and phytosphingosine. Phosphatidate, phosphatidylcholine and phosphatidylinositol are stimulatory, whereas cardiolipin and diacylglycerol are inhibitory. The expression of yeast PS synthase is transcriptionally repressed by myo-inositol and choline in a coordinate manner with other phospholipid-synthesizing enzymes. The upstream regulatory region of the PSS/CHO1 gene responsible for the myo inositol-choline regulation was identified. An octameric sequence, CATRTGAA (R = A or G), plays an important role in the conferral of the myo-inositol-choline transcriptional regulation. PMID- 9370338 TI - Phosphatidylserine decarboxylase. AB - Phosphatidylserine decarboxylase (PSD) is an important enzyme in the synthesis of phosphatidylethanolamine in both prokaryotes and eukaryotes. The cloned bacterial gene encodes an integral membrane protein that is first made as a proenzyme, and subsequently proteolyzed to an alpha subunit, containing a pyruvoyl prosthetic group, and a beta subunit. Two types of decarboxylases are found in yeast, PSD1 and PSD2, that localize to the inner mitochondrial membrane and the Golgi/vacuole membrane, respectively. The mammalian enzyme is also found in the inner mitochondrial membrane. The yeast genes and mammalian cDNA have been cloned and sequenced. The yeast genes contain 5' sequences associated with regulation of expression by inositol and choline. The yeast PSD1 and the mammalian PSD both contain an LGST amino acid motif that identifies the site of proteolysis and pyruvoyl prosthetic group attachment in the bacterial enzyme. The yeast PSD1 and mammalian PSD also have mitochondrial targeting and inner membrane sorting sequences. Processing intermediates have been defined in the mammalian enzyme that correspond to the sequential removal of the mitochondrial targeting and inner membrane sorting sequence, followed by formation of the alpha and beta subunits. In contrast, the PSD2 enzyme contains a putative Golgi localization/retention sequence and a C2 homology domain, in addition to predicted alpha and beta subunits. The transport requirements for substrate access to the PSD enzymes have provided important information about lipid trafficking, and the availability of yeast mutants is likely to provide important new genetic selections in the future. PMID- 9370339 TI - 1L-myo-inositol-1-phosphate synthase. AB - 1L-myo-Inositol-1-phosphate synthase catalyzes the conversion of D-glucose 6 phosphate to 1L-myo-inositol-1-phosphate, the first committed step in the production of all inositol-containing compounds, including phospholipids, either directly or by salvage. The enzyme exists in a cytoplasmic form in a wide range of plants, animals, and fungi. It has also been detected in several bacteria and a chloroplast form is observed in alga and higher plants. The enzyme has been purified from a wide range of organisms and its active form is a multimer of identical subunits ranging in molecular weight from 58,000 to 67,000. The activity of the synthase is stimulated by NH4Cl and inhibited by glucitol 6 phosphate and 2-deoxyglucose 6-phosphate. Structural genes (INO1) encoding the 1L myo-inositol-1-phosphate synthase subunit have been isolated from several eukaryotic microorganisms and higher plants. In baker's yeast, Saccharomyces cerevisiae, the transcriptional regulation of the INO1 gene has been studied in detail and its expression is sensitive to the availability of phospholipid precursors as well as growth phase. The regulation of the structural gene encoding 1L-myo-inositol-1-phosphate synthase has also been analyzed at the transcriptional level in the aquatic angiosperm, Spirodela polyrrhiza and the halophyte, Mesembryanthemum crystallinum. PMID- 9370340 TI - Function, gene organization and protein structures of 11beta-hydroxysteroid dehydrogenase isoforms. AB - Enzymatic interconversion of active and inactive glucocorticoid hormone is important, and is carried out physiologically by 11beta-hydroxysteroid dehydrogenase (11beta-HSD) isoforms, explaining their role in cellular and toxicological processes. Two forms of the enzyme, 11beta-HSD-1 and 11beta-HSD-2, belonging to the protein superfamily of short-chain dehydrogenases/reductases, have been structurally and functionally characterised. Although displaying dehydrogenase and reductase activities in vitro, the dominant in vivo function of the type-1 enzyme might be to work as a reductase, thus generating active cortisol from inactive cortisone precursors. On the other hand, for adrenal glucocorticoids the type-2 enzyme seems to be exclusively a dehydrogenase and, by inactivating glucocorticoids, confers specificity to peripheral mineralocorticoid receptors. PMID- 9370341 TI - Medical and physiological aspects of the 11beta-hydroxysteroid dehydrogenase system. AB - 11Beta-hydroxysteroid dehydrogenases (11beta-HSD) catalyse the interconversion of active glucocorticoids (cortisol, corticosterone) and their inert 11-keto derivatives (cortisone, 11-dehydrocorticosterone). The type-2 isozyme (11beta-HSD 2) is a high-affinity dehydrogenase that catalyses the rapid inactivation of glucocorticoids, thus ensuring selective access of aldosterone to otherwise non selective mineralocorticoid receptors in the distal nephron. Mutations of the gene encoding 11beta-HSD-2 are responsible for the syndrome of apparent mineralocorticoid excess, in which cortisol illicitly occupies mineralocorticoid receptors, causing hypertension and hypokalaemia. 11Beta-HSD-2 is also highly expressed in the placenta and mid-gestation fetus, where it may protect developing tissues from the often deleterious actions of glucocorticoids upon fetal growth and organ maturation. 11Beta-HSD-1 is probably an 11beta-reductase in vivo. Its function is obscure, but may amplify glucocorticoid action during the diurnal nadir, drawing upon the substantial circulating levels of 11-keto steroids. Both isozymes are regulated during ontogeny and by a series of hormonal and other factors. 11Beta-HSD provide an important control of glucocorticoid action at a cellular level, and may represent new targets for therapeutic intervention. PMID- 9370342 TI - Role of type-1 11beta-hydroxysteroid dehydrogenase in detoxification processes. AB - Carbonyl reduction is a significant step in the biotransformation leading to the elimination, of endogenous and exogenous aldehydes, ketones and quinones. This reaction is mediated by members of the aldo-keto reductase and short-chain dehydrogenase/reductase (SDR) superfamilies. The essential role of these enzymes in protecting organisms from damage by the accumulation of toxic carbonyl compounds is generally accepted, although their physiological roles are not always clear. Recently, the SDR enzyme 11beta-hydroxysteroid dehydrogenase-1 has been identified to perform an important role in the detoxification of non steroidal carbonyl compounds, in addition to metabolising its physiological glucocorticoid substrates. This review summarises the current knowledge of type-1 11beta-hydroxysteroid dehydrogenase and discusses possible substrate/inhibitor interactions. They might impair either the physiological function of glucocorticoids or the detoxification of non-steroid carbonyl compounds. PMID- 9370343 TI - Platination of a GG site on single-stranded and double-stranded forms of a 14 base oligonucleotide with diaqua cisplatin followed by NMR and HPLC -- influence of the platinum ligands and base sequence on 5'-G versus 3'-G platination selectivity. AB - Detailed studies of the kinetics of platination of the single-stranded 14-base DNA oligonucleotide d(ATACATGGTACATA) and the corresponding duplex by cis [Pt(NH3)2(H2O)2]2+ show that HPLC and NMR are complementary methods which provide similar results. The 5'-G and 3'-G monofunctional intermediates were trapped, separated and characterized by NMR (via 15NH3 labeling) and enzymatic digestion followed by mass spectrometry. The kinetic data are compared with those for the corresponding reactions of cis-[PtCl2(NH3)2] (cisplatin) and its monohydrolysed analogue. For both single and double strands of the oligonucleotide, the aqua complex shows little selectivity for the 5'-G or the 3'-G in the initial platination step, whereas the chloro-complex preferentially platinates the 3'-G. The base on the 3' side of the GG sequence appears to play an important role in controlling this selectivity; replacement of T by C increases the selectivity of duplex platination by the diaqua complex by a factor of about 6, and the selectivity of chelation of the 3'-G monofunctional adduct by a factor of about 3. In general the reactivity of the 5'-G in a GG sequence appears to be enhanced in a duplex compared with a single-strand. For both the aqua-monoadduct and chloro-monoadduct, cis-[Pt(NH3)2(N7G)(H2O or Cl)], the 5'-G monoadduct is much longer lived (t1/2 approximately 4 h at 288 K for aqua, 80 h at 298 K for chloro) than the 3'-G monoadduct (t1/2 < or = 45 min at 288 K for aqua, 6 h at 298 K for chloro). Inspection of molecular mechanics models of the end states of various monofunctional adducts provided insight into H-bonding and destacking interactions in these adducts and the sequence selectivity observed in their formation. Such adducts may play an important role in the mechanism of action of platinum anticancer drugs. PMID- 9370345 TI - Regulation of the flavin redox potential by flavin-binding antibodies. AB - Single-chain Fv antibody fragments binding different flavin forms [10-(5' carboxybutyl-)flavin (Fl[ox]) and 10-(5'-carboxybutyl)-1,5-dihydroflavin (Fl[red])] have been generated from an antibody phage-display library to study how a protein environment regulates the redox potential, starting from a protein other than a natural flavoprotein. These 'flavobodies' are characterized by time resolved and steady-state fluorescence spectroscopy, by competitive ELISA methods (mapping of the antigen-binding site), and by molecular modelling. The three dimensional models of the antigen-binding sites are consistent with the experimental results. Binding of anti-Fl(red) 5 to flavin increases the redox potential, mainly due to an Arg residue interacting with the flavin N1. Thus anti Fl(red) 5 shows an 'oxidase-like' redox-potential behaviour, confirming the idea that positively charged residues in the vicinity of N1 increase the redox potential. The results obtained with anti-Fl(ox), which do not resemble a natural flavoprotein, show that when the pyrimidine-like nucleus of the flavin is not involved in binding, the redox potential is not significantly affected. These results are in contrast to those obtained with chicken riboflavin-binding protein. PMID- 9370344 TI - Different consequences of incorporating chloroplast ribosomal proteins L12 and S18 into the bacterial ribosomes of Escherichia coli. AB - We have incorporated chloroplast ribosomal proteins (R-proteins) L12 and S18 into Escherichia coli ribosomes and examined the hybrid ribosomes for their ability to form polysomes in vivo and perform poly(U)-dependent poly(Phe) synthesis in vitro. The rye chloroplast S18 used for the experiment is a highly divergent protein (170 amino acid residues; E. coil S18, 74 residues), containing a repeating, chloroplast-specific, heptapeptide motif, and has amino acid sequence identity of only 35% to E. coli S18. When expressed in E. coli, chloroplast S18 was assembled in E. coli ribosomes. The latter formed polysomes in vivo at about the same rate as the host ribosomes, indicating that the replacement of E. coli S18 with its chloroplast homologue has only a minor, if any, effect on function. The L12 protein is much more conserved in sequence and chain length, and is known to have a very important function. The Arabidopsis chloroplast L12 used in the experiment was incorporated into E. coli 50S subunits that associated with the 30S subunits to form ribosomes, but the latter were unable to form polysomes. This result indicates functional inactivation of E. coil ribosomes by a chloroplast R-protein. To further confirm this result, we overproduced chloroplast L12 through the use of a secretion vector and purified the protein to homogeneity. Chloroplast L12 could be efficiently incorporated in vitro into L7/12-lacking E. coli ribosomes, but the hybrid ribosomes were totally inactive in poly(U)-dependent poly(Phe) synthesis. Computer modeling of the spatial structure of all known chloroplast L12 proteins (using E. coli L12 coordinates) indicated a 'chloroplast loop' present only in chloroplast L12. The presence of this loop might have a role in the observed inactivation. Taken together with previously reported results (summarized in this paper), it would appear that the features of chloroplast R-proteins concerned with specific functions are more divergent than their assembly properties. We have previously described methods suitable for overproduction and purification of chloroplast R-proteins that are encoded in organellar DNA (approximately 20), but that gave poor yield for those encoded in the nuclear DNA (approximately 45). Here we describe a method that overcomes this problem and allows the purification of nucleus-encoded chloroplast R-proteins in milligram quantities. PMID- 9370346 TI - Reactivity of the tyrosyl radical of Escherichia coli ribonucleotide reductase -- control by the protein. AB - Ribonucleotide reductase is a key enzyme for DNA synthesis. Its small component, named protein R2, contains a tyrosyl radical essential for activity. Consequently, radical scavengers are potential antiproliferative agents. In this study, we show that the reactivity of the tyrosyl radical towards phenols, hydrazines, hydroxyurea, dithionite and ascorbate can be finely tuned by relatively small modifications of its hydrophobic close environment. For example, in this hydrophobic pocket, Leu77-->Phe mutation resulted in a protein with a much higher susceptibility to radical scavenging by hydrophobic agents. This might suggest that the protein is flexible enough to allow small molecules to penetrate in the radical site. When mutations keeping the hydrophobic character are brought further from the radical (for example Ile74-->Phe) the reactivity of the radical is instead very little affected. When a positive charge was introduced (for example Ile74-->Arg or Lys) the protein was more sensitive to negatively charged electron donors such as dithionite. These results allow us to understand how tyrosyl radical sites have been optimized to provide a good stability for the free radical. PMID- 9370347 TI - Contribution of Arg288 of Escherichia coli elongation factor Tu to translational functionality. AB - The recently solved structure of the ternary complex formed between GTP-bound elongation factor Tu and aminoacylated tRNA reveals that the elements of aminoacyl-tRNA that interact with elongation factor Tu can be divided into three groups: the T stem; the 3'-end CCA-Phe; and the 5' end. The conserved residues Arg288, Lys89 and Asn90 are involved in the binding of the 5' end. In the active, GTP-bound form of the elongation factor, Arg288 and Asn90 are involved in the formation of a network of hydrogen bonds connecting the switch regions I and II of domain 1 with the rest of the molecule. This network is disrupted upon formation of the ternary complex. Arg288 was replaced by alanine, isoleucine, lysine or glutamic acid, and the resulting mutants have been subjected to an in vitro characterisation with the aim of clarifying the function of Arg288. Unexpectedly, the mutants behaved like the wild-type factor with regard to the association and dissociation of guanine nucleotides, and the intrinsic GTPase activities are unchanged. Furthermore, the mutants were as efficient as the wild type factor in carrying out protein synthesis in vitro in the presence of an excess of aminoacyl-tRNA. However, the mutants' abilities to bind aminoacyl-tRNA and protect the labile aminoacyl bond were impaired, especially where the charge had been reversed. PMID- 9370348 TI - Cloning of a putative G-protein-coupled receptor from Arabidopsis thaliana. AB - We have cloned and characterized a cDNA from Arabidopsis thaliana that most likely encodes a novel member of the vast superfamily of G-protein-coupled receptor proteins (GPCRs). By taking advantage of amino acid sequence similarities between plant expressed sequence tags (ESTs) and established G protein-coupled receptor sequences, a probe was obtained which was used for the screening of an Arabidopsis cDNA library. The cDNA which was found is very infrequently represented in the cDNA library, suggesting a low and/or spatially restricted expression. A region of the translated sequence of the cDNA shows the highest similarity to cAMP receptors from the slime mold Dictyostelium discoideum. The same region is also similar to that in members of the animal calcitonin family of receptors. Another region of the putative receptor, however, is similar to sequences of serotonin receptors and other receptors of the so called rhodopsin family of GPCRs. The rhodopsin family has numerous members in higher vertebrate species. Alignments and phylogenetic analyses of the regions of similarity yielded results in accordance with other evolutionary considerations. Our cDNA thus occurred on a distinct major branch in relation to the rest of the rhodopsin family. In relation to the calcitonin family, our cDNA and cAMP receptors occurred together on a distinct major branch but appear to have diverged from each other shortly after their divergence from the rest of the calcitonin family. Other features further argue for a tentative identification of it as a GPCR. It displays seven discrete and strongly predicted transmembrane domains when analyzed in hydropathy plots. The preferred orientation is with the amino terminus towards the outside. It has one Cys residue in extracellular loop 1 and another in extracellular loop 2. Cys residues in these loops are known to form disulfide bridges in many other GPCRs. Finally, it has several fully conserved amino acids that belong to the most conserved in previously known GPCRs, that occur in the above regions of similarity. PMID- 9370349 TI - Tumor-necrosis factor-alpha modulates mitogen-activated protein kinase activity of epidermal-growth-factor-stimulated MCF-7 breast cancer cells. AB - Tumor-necrosis factor(TNF)-alpha inhibited in a dose-dependent fashion the proliferation of epidermal-growth-factor(EGF)-stimulated MCF-7 breast cancer cells with an IC50 of 0.25 nM. A comparable TNF-alpha-mediated inhibition of p42/44 mitogen-activated protein (MAP) kinase activity was observed in 10 nM EGF stimulated cells. The MAP kinase activity dropped 50% within 3 min of TNF-alpha (1 nM) addition to EGF-stimulated MCF-7 cells. EGF and TNF-alpha, when added independently, led to a transient stimulation of MAP kinase activity with maximal activations within 6-8 min and 1-2 min, respectively. These observations suggest that MAP kinase activity in EGF-stimulated MCF-7 cells is modulated by the growth inhibitory receptor pathways of TNF-alpha. Phosphorylation measurements on western blots determined the involvement of several individual MAP kinases, namely p42/44 MAP kinases, p38 MAP kinase and c-Jun N2-terminal kinase 1 (JNK1), in EGF and TNF-alpha-induced signalling. Phosphorylation of p42 and p38 MAP kinases only was observed after treatment with either TNF-alpha or EGF. A combination of both ligands inhibited p42 and p38 MAP kinase phosphorylation in MCF-7 cells. In contrast, no JNK1 phosphorylation was detected in these cells. Simultaneous addition of okadaic acid, a potent inhibitor of phosphatases 1 and 2A, blocked the decay of EGF-stimulated MAP kinase activity over 40 min. TNF alpha added to EGF-stimulated and okadaic-acid-treated cells increased the MAP kinase activity twofold within 1 min. Similarly, okadaic acid treatment partly reverted the TNF-alpha-inhibited growth of MCF-7 cells. These experiments suggest that phosphatases are involved in the rapid shut-down by TNF-alpha of p42 MAP kinase activity. PMID- 9370350 TI - Dynamics of ubiquitin conjugation during heat-shock response revealed by using a monoclonal antibody specific to multi-ubiquitin chains. AB - Levels of intracellular multi-ubiquitinated proteins in heat-shocked HeLa cells were investigated using a monoclonal antibody specific to multi-ubiquitin chains. After heat-shock treatment at 42-44 degrees C for 30 min, the level of multi ubiquitinated proteins increased within the first 2 h at 37 degrees C and returned to the initial level within the following 2 h. The accumulation of multi ubiquitin conjugates was elevated by increasing the temperature, while the opposite was the case for the level of ubiquitinated histone H2A. Immunocytochemical analysis revealed that the amount of ubiquitin conjugates rapidly increased in the cytosol and concomitantly decreased in the nucleus under heat-shock conditions. The heat-shock treatment elicited little apparent change in the activity of the 26S proteasome, but it did induce a gradual increase in activity of the ubiquitinating enzyme system. These results strongly suggest that the level of cytoplasmic multi-ubiquitinated proteins and that of nuclear ubiquitinated histone H2A increases and decreases, respectively, in response to heat shock and that the heat-shock-induced accumulation of multi-ubiquitinated proteins is caused by activation of the ubiquitinating enzyme system rather than inactivation of the 26S proteasome. PMID- 9370351 TI - Expression of rat cGMP-binding cGMP-specific phosphodiesterase mRNA in Purkinje cell layers during postnatal neuronal development. AB - The cDNA encoding rat cGMP-binding, cGMP-specific phosphodiesterase (cGB-PDE) was isolated from a rat lung cDNA library. Although the deduced amino acid sequence showed 93.4% similarity with that of bovine cGB-PDE, the N-terminal portion of rat cGB-PDE was extremely different from that of bovine. Northern blot analysis indicated that cGB-PDE transcripts in rats were expressed not only in aorta and lung, but also in several other tissues including cerebellum. In situ hybridization analysis demonstrated that cerebellar expression of cGB-PDE was confined to Purkinje cell layers in adult rats. To clarify the role of cGB-PDE in the cerebellum, we investigated expression of cGB-PDE mRNA in rats of various ages. cGB-PDE mRNA was not observed in the cerebellum of newborn rats, but levels of a cGB-PDE mRNA were markedly increased between 4 days and 28 days of age and reached a maximum in eight-week-old rats. In this study, we suggest that cGB-PDE plays important roles not only in regulating the relaxation of vascular vessels, but also in establishing neuronal networks in the cerebellum at an early postnatal stage. In addition the NO/cGMP/cGB-PDE pathway appears to be essential for the induction of long-term depression. PMID- 9370352 TI - Cloning and characterization of the arginine-specific carbamoyl-phosphate synthetase from Bacillus stearothermophilus. AB - Bacillus stearothermophilus contains two carbamoyl-phosphate synthetases (CPS), one specific for pyrimidine biosynthesis and the other for arginine biosynthesis. The pyrimidine-specific CPS is repressed by exogenous pyrimidines, and its activity is inhibited by UMP and activated by 5-phospho-alpha-D-ribosyl diphosphate. The arginine-specific CPS is similarly repressed by exogenous arginine but its activity is not sensitive to these or other potential effectors. Each of the two enzymes consist of two unequal subunits, as is the case for other microbial CPS; however, the large subunit for the arginine-specific CPS is smaller than that for the pyrimidine-specific enzyme. Comparison of the derived amino acid sequence for the cloned large subunit of the arginine-specific CPS with those for subunits from pyrimidine-sensitive CPS showed significant similarity throughout the polypeptides except at the carboxy terminus, which was identified by other laboratories to contain the binding site for the pyrimidine effector. Unlike the results previously reported for CPS from an enteric mesophile, the kinetic properties of the arginine-specific CPS were not affected by growth of B. stearothermophilus at temperatures near the minimal growth temperature. Furthermore, calorimetric studies showed that the thermal stability of cloned CPS was identical regardless of the growth temperature of B. stearothermophilus between 42 degrees C and 63 degrees C. The thermal stability of cloned CPS was not affected by expression at 37 C in Bacillus subtilis or Escherichia coli. In contrast, the thermal stabilities for CPS and other proteins were higher in extracts of cells grown at higher temperatures. These results indicate that cellular factors, probably chaperonins, are necessary for thermal stability of proteins at and below the optimal temperature for this thermophile. PMID- 9370353 TI - Changes in composition of newly synthesized sphingolipids of HeLa cells during the cell cycle -- suppression of sphingomyelin and higher-glycosphingolipid synthesis and accumulation of ceramide and glucosylceramide in mitotic cells. AB - Sphingolipid biosynthesis in synchronized HeLa cells was studied by pulse labeling with [14C]Ser or [14C]Gal and a simple TLC method. The major HeLa cell sphingolipids are ceramide (Cer), sphingomyelin, glucosylceramide (GlcCer), lactosylceramide (LacCer), globotriaosylceramide (Gb3Cer), N acetylneuraminosylgangl iotriaosylceramide (GM2) and sialylparagloboside (G[M1 GlcNAc]). The sphingolipid biosynthetic profiles of HeLa cells in the G1, G1/S boundary, S and G2 phases were similar, but significant changes occurred during M phase, when incorporation of radioactivity into sphingomyelin, Gb3Cer and a mixture of GM2 and G(M1-GlcNAc) decreased, and those of Cer and GlcCer increased. These data indicate that transfer of phosphocholine and galactose to Cer and GlcCer, respectively, decreased in mitotic cells, resulting in accumulation of Cer and GlcCer. Analysis of LacCer synthase activity revealed that GlcCer accumulation was not due to reduced activity of this enzyme. The results suggest that Cer and GlcCer accumulation in mitotic cells resulted from suppression of sphingomyelin and LacCer synthesis, probably caused by vesiculation of membranous organelles, such as the endoplasmic reticulum and Golgi apparatus. PMID- 9370354 TI - Topological photoaffinity labeling of the rabbit ileal Na+/bile-salt-cotransport system. AB - For the investigation of the topology of the rabbit ileal Na+/bile-salt cotransport system, composed of a 93-kDa integral membrane protein and a peripheral 14-kDa bile-acid-binding protein (ILBP), we have synthesized photolabile dimeric bile-salt-transport inhibitors (photoblockers), G1-X-G2, where two bile acid moieties (G1 and G2) are tethered together via a spacer, X, and where one of the two bile acid moieties carries a photoactivatable group. These photoblockers specifically interact with the ileal Na+/bile-salt cotransport system as demonstrated by a concentration-dependent inhibition of [3H]cholyltaurine uptake by rabbit ileal brush-border membrane vesicles and by inhibition of photolabeling of the 93-kDa and 14-kDa bile-salt-binding proteins by 7,7-azo and 3,3-azo derivatives of cholyltaurine. Ileal bile-salt uptake was specifically inhibited by the photoblockers, which were not taken up themselves by the small intestine as demonstrated by in vivo ileal perfusion. Dependent on the photoblocker used several polypeptides in the molecular-mass range of 14-130 kDa were labeled. The cytoplasmically attached 14-kDa ILBP was significantly labeled only by inhibitors that are photoactivatable in bile acid moiety G1, suggesting that during binding and translocation of a bile-salt molecule by the ileal bile-salt-transport system the steroid nucleus gets access to the cytoplasmic site of the ileal brush-border membrane first. Photoaffinity labeling in the frozen state with the transportable 3,3-azo and 7,7-azo derivatives of cholyltaurine revealed a time-dependent increase in the extent of labeling of the 14-kDa and 93-kDa proteins, suggesting a labeling of these proteins from the cytoplasmic site of the ileal brush-border membrane. By photoaffinity labeling in the frozen state with the various photoblockers time-dependent changes in the extent of photoaffinity labeling of bile-salt-binding proteins were observed, demonstrating the possibility of topological analysis of the rabbit ileal Na+/bile-salt-cotransport system. PMID- 9370355 TI - Ultraviolet-B-radiation-induced changes in nicotinamide and glutathione metabolism and gene expression in plants. AB - Pea (Pisum sativum L. cv. Greenfeast) plants were exposed to supplementary ultraviolet-B (UV-B) radiation (biologically effective dose rates normalised to 300 nm, UV-B[BE,300]: 0.18, 0.32 or 1.4 W m[-2]). Leaf nicotinamide, trigonelline, GSHtot (total glutathione) and GSSG (oxidised glutathione) levels remained unchanged after exposure to the lowest dose rates. 1.4 W m(-2) UV B(BE,300) gave rise to 60-fold and 4.5-fold increases in GSSG and GSHtot, respectively. 3.5-fold and 9.5-fold increases were found in nicotinamide and trigonelline, respectively. cab (Chlorophyll-a/b-binding protein) transcript levels decreased and CHS (chalcone synthase) and PAL (phenylalanine ammonia lyase) mRNA increased after shorter UV-B exposures (hours) to the higher dose rate of UV-B, and after exposure to the intermediate dose rate. CHS and PAL mRNAs also increased after prolonged exposure to the lowest dose rate. cab transcripts completely disappeared, whereas CHS and PAL mRNA levels rose by 60-fold and 17 fold, respectively, after 12 h exposure at the highest dose rate and 12 h of development. Our results indicate that nicotinamide or trigonelline do not function as signalling compounds for CHS and PAL gene expression. Elevated nicotinamide and trigonelline levels occur in response to UV-B, but only at UV-B doses high enough to cause oxidative stress. PMID- 9370356 TI - Comparative study in vivo and in vitro of uniformly 14C-labelled and 125I labelled recombinant fibroblast growth factor 2. AB - Recombinant bovine fibroblast growth factor (FGF2), uniformly labelled with 14C ([14C]FGF2), was purified and showed to be highly stable and to retain full biological activity. Organ distribution of [14C]FGF2 after intravenous injection of young rats was assessed by autoradiography of whole body sections and compared with those obtained with [125I]iodinated FGF2 (125I-FGF2). Thyroid, stomach, intestine, bladder and skin were radioactively labelled only in the case of 125I FGF2. This tissue-labelling is artefactual, probably due to free iodide binding not observed when using [14C]FGF2. High-resolution autoradiography showed a complex tissue distribution of [14C]FGF2 in kidney and adrenal organs. Incubation of frozen eye sections with [14C]FGF2 showed a specific and high-resolution labelling pattern of ocular tissues. After cellular internalization, [14C]FGF2 was processed into five distinct polypeptides of 16, 14, 8, 7, and 5.5 kDa. The 14-kDa and 7-kDa polypeptides are novel catabolic fragments not detected with radioiodinated FGF2. In terms of stability, tissue distribution specificity, and autoradiographic resolution, [14C]FGF2 proved to have more advantages than 125I FGF2 for pharmacokinetic and catabolism studies. PMID- 9370357 TI - PCTAIRE 2, a Cdc2-related serine/threonine kinase, is predominantly expressed in terminally differentiated neurons. AB - PCTAIRE are members of a subfamily of Cdc2-related kinases that have been shown to be preferentially expressed in post-mitotic cells. To examine the neural functions of PCTAIRE, rat cDNA clones encoding PCTAIRE 1, 2, and 3 were isolated, and their expression patterns in the brain were analyzed. Among the three rat PCTAIREs, only PCTAIRE 2 was found to be specifically expressed in the brain. Furthermore, its expression was transiently increased during brain development, peaking 7-15 days after birth. Within the brain, PCTAIRE 2 was concentrated in the neuronal layers of the hippocampus and olfactory bulb, which mostly consist of post-mitotic neurons. In an immunocytochemical experiment, immunoreactivity for PCTAIRE 2 was detected in the cell bodies and extended neurites of neurons, but not in astrocytes. The PCTAIRE 2 protein was recovered in the particulate fraction and resistant to solubilization with non-ionic detergent, suggesting that PCTAIRE 2 might be present as a component of a large protein complex. An immunoprecipitation assay revealed that the PCTAIRE 2 was associated with Ser/Thr phosphorylating activity for histone H1, and that its activity depended on association with a regulatory partner that can be released under high-salt conditions. These findings suggest that PCTAIRE 2 is a Ser/Thr kinase that might play a unique role in terminally differentiated neurons. PMID- 9370358 TI - DNA methylation accounts for the inhibition of collagen VI expression in transformed fibroblasts. AB - The expression of collagen VI, an adhesive glycoprotein of the extracellular matrix, is completely inhibited in virally transformed fibroblasts and in many cell lines derived from spontaneous mesenchymal tumors. Here we present evidence that DNA methylation plays an important role in this inhibition: (a) The mRNA level for DNA methyltransferase is highly increased in simian virus 40 (SV40) transformed fibroblasts compared with normal cells and this increase correlates with the decrease of the mRNA level for collagen VI. (b) Methylation of the alpha2(VI) collagen promoter in vitro abolishes promoter activity in a transient transfection assay. (c) Genomic sequencing reveals extensive methylation of the promoter region in SV40-transformed cells, but virtually no methylation of the corresponding region in normal cells. Increased methylation is also observed in a rhabdomyosarcoma cell line. (d) Two of the cis-acting elements of the alpha2(VI) collagen promoter lose their affinity for transcription factor AP2 when methylated in vitro as demonstrated by gel retardation experiments. DNA methylation is therefore involved in the silencing of the alpha2(VI) collagen gene. It seems likely that the same mechanism is also responsible for the repression of other transformation-sensitive proteins. PMID- 9370359 TI - Transport of CtpA protein from the cyanobacterium Synechocystis 6803 across the thylakoid membrane in chloroplasts. AB - The CtpA protein in the cyanobacterium Synechocystis 6803 is a C-terminal processing protease that is essential for the assembly of the manganese cluster of the photosystem II complex. When fused to different chloroplast-targeting transit peptides, CtpA can be imported into isolated spinach chloroplasts and is subsequently translocated into the thylakoid lumen. Thylakoid transport is mediated by the cyanobacterial signal peptide which demonstrates that the protein transport machinery in thylakoid membranes is functionally conserved between chloroplasts and cyanobacteria. Transport of CtpA across spinach thylakoid membranes is affected by both nigericin and sodium azide indicating that the SecA protein and a transthylakoidal proton gradient are involved in this process. Saturation of the Sec-dependent thylakoid transport route by high concentrations of the precursor of the 33-kDa subunit of the oxygen-evolving system leads to a strongly reduced rate of thylakoid translocation of CtpA which demonstrates transport by the Sec pathway. However, thylakoid transport of CtpA is affected also by excess amounts of the 23-kDa subunit of the oxygen-evolving system, though to a lesser extent. This suggests that the cyanobacterial protein is capable of also interacing with components of the deltapH-dependent route and that transport of a protein across the thylakoid membrane may not always be restricted to a single pathway. PMID- 9370360 TI - Characterization of a stable intermediate trapped during reversible refolding of Bacillus subtilis alpha-amylase. AB - Bacillus subtilis exocellular alpha-amylase is reversibly refolded after denaturation by guanidine hydrochloride at pH 7 and 37 degrees C. The unfolding folding transition monitored by intrinsic fluorescence changes and resistance to proteolysis was resolved into a two-state transition. The first step (t1/2 < 1 s) led from D, the totally unfolded state, to C, a stable partially structured state of the protein. This folding intermediate was devoid of any enzyme activity and partially resistant to protease degradation. Calcium was required for the transition from C to N, the native state. This metal did not remain associated with the native form and could be replaced by barium or strontium, but not by magnesium. We discuss the hypothesis that C, the folding intermediate whose further transformation is under kinetic control, is the competent state involved in the secretion process of alpha-amylase. PMID- 9370361 TI - Amino acid sequence, binding properties and evolutionary relationships of the basic liver fatty-acid-binding protein from the catfish Rhamdia sapo. AB - The complete amino acid sequence of a basic liver fatty acid-binding protein (L FABP) from catfish (Rhamdia sapo) was determined. Alignment of sequences shows that it has more similarity to chicken basic L-FABP than to mammalian L-FABP. The phylogenetic analysis suggests that basic L-FABP from catfish, chicken and iguana diverged from the mammalian protein before the fish-tetrapod divergence, thus implying that the two types are encoded by different genes. Supporting this conclusion, a 14-kDa protein, structurally closely related to mammalian L-FABP, was isolated from catfish intestine, indicating the presence of the two genes in the same species. The catfish basic L-FABP binds only one fatty acid/molecule, while mammalian L-FABP bind two. The former has more affinity for trans-parinaric acid than for cis-parinaric acid, in constrast to the latter proteins. PMID- 9370362 TI - Characterization of dopuin, a polypeptide with special residue distributions. AB - A 62-residue polypeptide, dopuin, has been isolated from pig small intestine. It is distinguished by an N-terminal part with a high content of proline (7 in a 26 residue segment), a C-terminal part with a high proportion of histidine (3 in a 9 residue segment), and six half-cystine residues in three intrachain disulphide bridges (connecting positions 22-25, 23-54 and 35-44). The Cys and Pro distributions suggest a tight and special conformation. In contrast to PEC-60 and somatostatin, it has no established inhibitory effect on insulin secretion. At 10 nM concentration, a weak inhibitory tendency is less than half of that of the other two peptides. Like gastrointestinal trefoil peptides, dopuin has three disulphide bridges, Ala-Pro segments, and many charged residues, but they are differently distributed and dopuin belongs to a separate, apparently novel family. However, dopuin is similar to a peptide corresponding to an expressed sequence-tag cDNA of human fetal liver and spleen, establishing the nature of the mature form of the product of this cDNA, and showing a general tissue, age, and species distribution of this peptide. A truncated form of vimentin, composed of its C-terminal 37 residues, vimentin-C37, was also purified and structurally characterized. These two peptides increase the complexity of known intestinal polypeptides and at least dopuin has properties compatible with specific biofunctions. PMID- 9370363 TI - Crystallographic analysis of human immunodeficiency virus 1 protease with an analog of the conserved CA-p2 substrate -- interactions with frequently occurring glutamic acid residue at P2' position of substrates. AB - Human immunodeficiency virus type 1 (HIV-1) protease hydrolysis of the Gag CA-p2 cleavage site is crucial for virion maturation and is optimal at acidic pH. To understand the processing of the CA-p2 site, we have determined the structure of HIV-1 protease complexed with an analog of the CA-p2 site, the reduced peptide inhibitor Arg-Val-Leu-r-Phe-Glu-Ala-Ahx-NH2 [r denotes the reduced peptide bond and Ahx 2-aminohexanoic acid (norleucine), respectively]. The crystal structure was refined to an R-factor of 0.17 at 0.21-nm resolution. The crystals have nearly the same lattice as related complexes in P2(1)2(1)2(1) which have twofold disordered inhibitor, but are in space group P2(1). and the asymmetric unit contains two dimers of HIV-1 protease related by 180 degrees rotation. An approximate non-crystallographic symmetry has replaced the exact crystal symmetry resulting in well-ordered inhibitor structure. Each protease dimer binds one ordered inhibitor molecule, but in opposite orientations. The interactions of the inhibitor with the two dimers are very similar for the central P2 Val to P2' Glu residues, but show more variation for the distal P3 Arg and P4' Ahx residues. Importantly, the carboxylate oxygens of Glu at P2' in the inhibitor are within hydrogen-bonding distance of a carboxylate oxygen of Asp30 of the protease suggesting that the two side chains share a proton. This interaction suggests that the enzyme-substrate complex is additionally stabilized at lower pH. The importance of this interaction is emphasized by the absence of polymorphisms of Asp30 in the protease and variants of P2' Glu in the critical CA-p2 cleavage site. PMID- 9370364 TI - The 40-kDa component of the phagocyte NADPH oxidase (p40phox) is phosphorylated during activation in differentiated HL60 cells. AB - The superoxide-generating NADPH oxidase complex of phagocytic cells is a multicomponent system containing a membrane-bound flavocytochrome b and a small G protein Rac as well as cytosolic factors p67phox, p47phox and p40phox which translocate to the membrane upon activation. Known mechanisms underlying the translocation of these proteins include polyphosphorylation of p47phox and specific Src homology 3/polyproline motif interactions. In this study, through two-dimensionnal electrophoresis and immunoprecipitation experiments, we show using dimethylsulfoxide-differentiated HL60 promyelocytes that p40phox is in a basal phosphorylated state in resting cells and undergoes further phosphorylation on multiple sites upon stimulation of the NADPH oxidase by either phorbol myristate acetate or by the formyl peptide fMet-Leu-Phe-Lys. Moreover, the extent of phosphorylation is strongly correlated with the level of superoxide production. Typically, in cells transiently activated by fMet-Leu-Phe-Lys, onset of superoxide production coincides with the appearance of new phosphorylated species of p40phox and, at the end of the respiratory burst, dephosphorylation of p40phox is observed. In vitro assays show that the kinase(s) involved in the phosphorylation of p40phox differ from those which participate in the phosphorylation of p47phox. This suggests that, in the cell, the phosphorylation of p40phox and of p47phox are under the control of two different kinase pathways. PMID- 9370365 TI - Dimerization of the synaptic vesicle protein synaptobrevin (vesicle-associated membrane protein) II depends on specific residues within the transmembrane segment. AB - Synaptobrevin is an integral membrane protein of presynaptic vesicles and is essential for neurotransmitter release. Previously, a dimeric quaternary structure has been proposed by cross-linking experiments performed on brain fractions. Here, we demonstrate that heterologously expressed and solubilized synaptobrevin II forms a homodimer. The dimers were detected upon cross-linking with a homobifunctional lysine-reactive reagent or by oxidation of the single cysteine residue located within the transmembrane segment. Dimerization was also observed without prior cross-linking upon SDS/PAGE under mild conditions. Interestingly, dimerization required the presence of the transmembrane segment which therefore is inferred to be the principal site of subunit-subunit interaction. The residues comprizing this segment were individually mutated. Dimerization of some point mutants was significantly impaired, which proved the sequence specificity of interaction and identified residues contributing to the subunit-subunit interface. The distribution of these residues (Leu99, Ile102, Cys103, Leu107, Ile110, and Ile111) suggests that the transmembrane segment has an alpha-helical structure and that the helices pair in a right-handed fashion. The importance of the transmembrane segment for subunit-subunit interaction relates synaptobrevin to fusogenic membrane proteins of enveloped viruses where transmembrane segments have been implicated in both oligomerization and membrane fusion. PMID- 9370366 TI - The Ca2+-mobilizing potency of alpha-thrombin and thrombin-receptor-activating peptide on human platelets -- concentration and time effects of thrombin-induced Ca2+ signaling. AB - In single platelets and in suspensions of platelets, alpha-thrombin evokes dose dependent, transient increases in cytosolic Ca2+ concentration, [Ca2+]i, which are more prolonged than the [Ca2+]i transients evoked by other platelet agonists such as the thrombin-receptor-activating hexapeptide SFLLRN, thromboxane A2 analog U46619, and ADP. As a quantity taking into account both the magnitude and length of the Ca2+ response, we defined the Ca2+-mobilizing potency (CMP) of an agonist as the integrated rise in [Ca2+]i during the time of the Ca2+ signal. It was observed that: (a) the CMP increased with the agonist concentration in a saturating way, its maximal value being about four-times higher with alpha thrombin than with SFLLRN; (b) the high CMP of alpha-thrombin was for only a small part due to endogenous production of ADP or thromboxane, and was mainly a consequence of prolonged influx of external Ca2+; (c) the CMP declined when alpha thrombin was inactivated during the course of the Ca2+ signal; (d) CMP values increased with the agonist concentration upon sequential addition of increasing amounts of alpha-thrombin or SFLLRN; (e) when alpha-thrombin was gradually added to the platelets or formed by an in situ reconstituted prothrombinase system (with factor Xa, factor Va, and prothrombin), integrated Ca2+ responses were a function of the product of the alpha-thrombin concentration and the time of its presence. However, in these cases, the final CMP values were independent of the rate of alpha-thrombin addition or formation. We conclude that alpha-thrombin induced Ca2+ signals in platelets rely largely upon Ca2+ influx, are not, or only slightly, subjected to homologous desensitization, and reflect the enzymatic capacity of alpha-thrombin to cleave protease-activated receptors. Thus, the high and prolonged Ca2+ signal induced by alpha-thrombin is due to continuous receptor cleavage without desensitizing effects of previously cleaved receptors. PMID- 9370367 TI - The role of ferredoxin-NADP+ reductase in the concerted cell defense against oxidative damage -- studies using Escherichia coli mutants and cloned plant genes. AB - Ferredoxin-NADP+ reductases (FNR) participate in cellular defense against oxidative damage. Escherichia coli mutants deficient in FNR are abnormally sensitive to methyl viologen and hydrogen peroxide. Tolerance to these oxidants was regained by expression of plant FNR, superoxide dismutase, or catalase genes in the mutant cells. FNR contribution to the concerted defense against viologen toxicity under redox-cycling conditions was similar to that of the two major E. coli superoxide dismutases together, as judged by the phenotypes displayed by relevant mutant strains. However, FNR expression in sodA sodB strains failed to increase their tolerance to viologens, indicating that the FNR target is not the superoxide radical. Sensitivity of FNR-deficient cells to oxidants is related to extensive DNA damage. Incubation of the mutant bacteria with iron chelators or hydroxyl radical scavengers provided significant protection against viologens or peroxide, suggesting that oxidative injury in FNR-deficient cells was mediated by intracellular iron through the formation of hydroxyl radicals in situ. The NADP(H)-dependent activities of the reductase were necessary and sufficient for detoxification, without participation of either ferredoxin or flavodoxin in the process. Possible mechanisms by which FNR may exert its protective role are discussed. PMID- 9370368 TI - Molecular characterisation of the pifC gene encoding translation initiation factor 3, which is required for normal photosynthetic complex formation in Rhodobacter sphaeroides NCIB 8253. AB - In order to determine whether translation initiation events play a selective role in regulating the expression of photosynthetic complexes in the photosynthetic bacterium Rhodobacter sphaeroides, we have undertaken an initial study to investigate the potential role of translation initiation factor IF3, which also behaves as a pleiotropic regulatory factor in some bacteria. Following the isolation and purification of a 24-kDa IF3-like protein (PifC) from R. sphaeroides, we used nested PCR to clone and characterise the encoding gene, pifC (photosynthesis-affecting initiation factor). The 545-bp pifC encodes a protein exhibiting 60% identity (78.6% similarity) with the Escherichia coli IF3 (InfC) protein and, in common with all other IF3 genes identified to date, pifC possesses a rare initiation codon (AUA). Furthermore, in common with IF3, PifC was shown here to perform a discriminatory function towards CUG start codons, confirming its role and function as an IF3 in R. sphaeroides. Insertion of a kanamycin resistance cassette into the 5' end of pifC resulted in a viable phenotype which exhibits growth rates similar to wild type but which possesses reduced bacteriochlorophyll and photosynthetic complexes in semi-aerobic cultures. It is shown here that the mutant is still able to produce a PifC protein but that it possesses reduced IF3 activity. This may account for the viable nature of the mutant strain, and may indicate that the effect of the mutation on photosynthesis can be more severe than shown in the present study. The mechanisms by which PifC may exert its selective regulatory effect on photosynthesis expression are discussed. PMID- 9370369 TI - Design and NMR study of an immobile DNA four-way junction containing 38 nucleotides. AB - The DNA Holliday junction is a central intermediate in genetic recombination. We have designed and synthesized a DNA oligomer, J1a, as a model compound for the Holliday junction suitable to be studied by NMR spectroscopy and future molecular modelling. The design was based on a 46-base oligomer, J4, previously studied by Pikkemaat, J. A., van den Elst, H., van Boom, J. H. & Altona, C. [Biochemistry 33, 14896-14907 (1994)], including the propensity to undergo a self-folding process to give a four-way junction in which three of the four arms are capped with a hairpin loop. J1a, however, is considerably shortened by eight bases and thus contains only 38 residues which significantly facilitates the proton resonance assignments. The base sequence at the branch point is identical to that in J4. 1H-NMR data clearly point to the presence of three hairpin loops in J1a and show that the double-helical arms adopt the B-DNA form. Quasicontinuous pairwise stacking between helical arms to give a single preferred stacked X conformation is evident. The extent of folding into this stacked conformation is strongly dependent upon the magnesium concentration. Full Watson-Crick base pairing at the branch point is completely preserved. The A/D-stacking preference of the small junction is the same as that exhibited by J4. PMID- 9370370 TI - cDNA cloning of a Trichoderma reesei cellulase and demonstration of endoglucanase activity by expression in yeast. AB - A Trichoderma reesei cDNA encoding a previously unknown protein with a C-terminal cellulose-binding domain was obtained by complementation screening of a T. reesei cDNA library in a sec1 yeast mutant impaired in protein secretion. The T. reesei protein shows amino acid similarity over its entire length to the Agaricus bisporus cellulose-induced protein CEL1 whose function is not known. These two proteins form a new glycosyl hydrolase family, number 61. Expression of the T. reesei cDNA in yeast showed that it encoded a protein with endoglucanase activity and thus the protein was named EGIV and the corresponding gene egl4. Polyclonal antibodies were prepared against EGIV produced in Escherichia coli and detected a 56-kDa protein in the T. reesei culture supernatant. Northern hybridisation revealed that T. reesei egl4 is regulated in the same manner as other cellulase genes of this fungus. PMID- 9370371 TI - In vitro assembly properties of purified bacterially expressed capsid proteins of human immunodeficiency virus. AB - The Gag polyprotein of retroviruses is sufficient for assembly and budding of virus-like particles from the host cell. In the case of human immunodeficiency virus (HIV), Gag contains the domains matrix, capsid (CA), nucleocapsid (NC) and p6 which are separated by the viral proteinase inside the nascent virion, leading to morphological maturation to yield an infectious virus. In the mature virus, CA forms a capsid shell surrounding the ribonucleoprotein core consisting of NC and the genomic RNA. To define requirements for particle assembly and functional contributions of individual domains, we expressed domains of HIV Gag in Escherichia coli and purified the products to near homogeneity. In vitro assembly of CA, with or without the C-terminally adjacent spacer peptide, yielded tubular structures with a diameter of approximately 55 nm and heterogeneous length. Efficient particle formation required high protein concentration, high salt and neutral to alkaline pH. In contrast, in vitro assembly of CA-NC occurred at a 20 fold lower protein concentration and in low salt, but required addition of RNA. These results suggest that hydrophobic interactions of capsid proteins are sufficient for particle formation while the RNA-binding nucleocapsid domain may concentrate and align structural proteins on the viral genome. PMID- 9370372 TI - Mutagenesis and ligand modification studies on galanin binding to its GTP-binding protein-coupled receptor GalR1. AB - In this study, a large number of receptor mutants were generated and several N terminally modified galanin analogues synthesized to refine the previously proposed binding site model for galanin to its GTP-binding-protein-coupled receptor GalR1. In addition to ligand-binding studies, the functionality of mutant receptors was evaluated by assessing their ability to mediate galaninergic inhibition of isoproterenol-stimulated adenylyl cyclase activity. The His264Ala and Phe282Ala receptor mutants, although deficient in binding in the concentration range of galanin used, remain functional albeit 20-fold less efficient than the wild-type receptor in mediating inhibition of stimulated cAMP production by galanin. The His267Ala mutant is, apart from being deficient in galanin binding, also severely impaired in functional coupling. While His264 and Phe282 seem to be important in forming the binding pocket for galanin, His267 might play a role in forming or stabilizing the active conformation of the GalR1 receptor rather than directly participating in the formation of the binding pocket for galanin. N-terminal carboxylic acid analogues of galanin have low affinity to wild-type GalR1, but substantially increased affinity to the Glu271Lys receptor mutant. This, together with the finding that an alanine substitution of Phe115 in TM III results in a tenfold decrease in affinity for galanin, suggests that the N-terminus of galanin interacts with Phe115. In contrast to the Phe282Ala mutation in TM VII, a conservative mutation of Phe282 to tyrosine did not alter the affinity for galanin. Thus, the interaction between Tyr9 of galanin and Phe282 is likely to be of an aromatic-aromatic nature. PMID- 9370373 TI - Stabilisation of halophilic malate dehydrogenase from Haloarcula marismortui by divalent cations -- effects of temperature, water isotope, cofactor and pH. AB - Halophilic malate dehydrogenase is stable in a limited concentration range of MgCl2 or CaCl2. Thermal deactivation of the protein at low concentrations of these divalent salts is very different from that occurring at high concentrations. In low salt, stability always increases as the temperature is lowered. In high salt, stability shows bell-shaped behaviour as a function of temperature: increasing to a maximum at 4 degrees C, and subsequently decreasing as the temperature is lowered. This is in contrast to other salts, for which the deactivation behaviour depends on the salt type but not on its concentration. Cofactor addition or replacement of H2O by D2O modify only the deactivation at low MgCl2 or CaCl2 concentrations. A pH transition between pH 7 and pH 8, however, modified enzyme deactivation at both low and high MgCl2 or CaCl2 concentrations. The pH effect on stability was also observed in other salts. By comparing the effect of CaCl2, MgCl2, and NaCl, a strong correlation was found between the minimum salt concentration required for the stabilisation of halophilic malate dehydrogenase and the hydration of the cation. PMID- 9370375 TI - Acceleration of unisite catalysis of mitochondrial F1-adenosinetriphosphatase by ATP, ADP and pyrophosphate--hydrolysis and release of the previously bound [gamma 32P]ATP. AB - The effect of ATP, ADP and pyrophosphate (PPi) on hydrolysis and release of [gamma-32P]ATP bound to the high-affinity catalytic site of soluble F1 from bovine heart mitochondria under unisite conditions [Grubmeyer, C., Cross, R. L. & Penefsky, H. S. (1982) J. Biol. Chem. 257, 12092-12100] was studied. In accord with the previous data, it was observed that millimolar concentrations of ATP or ADP added to F1 undergoing unisite hydrolysis of [gamma-32P]ATP accelerated its hydrolysis. PPi also produced a hydrolytic burst of a fraction of the previously bound [gamma-32P]ATP; kinetic data suggested that for production of optimal hydrolysis by PPi of the bound [gamma-32P]ATP, two binding sites with apparent Kd of 27 microM and 240 microM must be filled. The extent of the hydrolytic burst induced by MgPPi was lower than that induced by ADP and ATP. In F1 in which PPi had produced a hydrolytic burst of the bound [gamma-32P]ATP, the addition of ATP induced a second burst of hydrolysis. By filtration experiments and enzyme trapping, it was also studied whether ATP, ADP and PPi produce release of the tightly bound [gamma-32P]ATP. At millimolar concentrations, ATP and ADP brought about release of about 25% of the previously bound [gamma-32P]ATP. At micromolar concentrations, ADP accelerated the hydrolysis of the previously bound [gamma 32P]ATP but not its release. Hence, the hydrolytic and release reactions could be separated, indicating that the two reactions require the occupancy of different sites in F1. With PPi, no release of the tightly bound [gamma-32P]ATP was observed. The ADP induced hydrolysis and release of the F1-bound [gamma-32P]ATP were inhibited by sodium azide to the same extent (60%). Since release of ATP from a high-affinity catalytic site of F1 represents the terminal step of oxidative phosphorylation, the data illustrate that the binding energy of substrates to F1 is critical to the ejection of ATP into the media. The failure of PPi to induce release of [gamma-32P]ATP bound to F1 under unisite conditions is probably due to its lower binding energy. PMID- 9370374 TI - Subcellular localization, substrate specificity and crystallization of duodenase, a potential activator of enteropeptidase. AB - Duodenase, a serine protease from bovine duodenum mucosa, was located in endoplasmic reticulum, the Golgi secretory granules of epithelial cells and ducts of Brunner's glands by the A-gold immunocytochemical method. Duodenase exhibits trypsin-like and chymotrypsin-like specificities with a preference for substrates having lysine at the P1 and proline at the P2 positions. The kinetic constants for the hydrolysis of 21 potential duodenase substrates are reported. The best substrates were found to be alpha-N-tosylglycylprolyllysine 4-nitroanilide (k[cat]/Km of 35000 M[-1] s[-1]), alpha-N-succinylthreonylprolyllysine 4 nitroanilide (k[cat]/Km of 18000 M[-1] s[-1]) and alpha-N-serylprolyllysine 4 nitroanilide (k[cat]/Km of 2600 m[-1] s[-1]), all of which contain the P1-P3 sequence of the enteropeptidase zymogen/activation site. On the basis of its catalytic properties and sites of localization, duodenase has been postulated to be an activator of the enteropeptidase precursor. A tetradecapeptide (LVTQEVSPKIVGGS) having the P9-P5'sequence of the cleavage site of zymogen activation of bovine proenteropeptidase was synthesized, and kinetic parameters of its hydrolysis by duodenase were determined (Km of 87 microM; k[cat] of 1.4 s[ 1]; k[cat]/Km of 16000 M[-1] s[-1]). Crystals of duodenase frozen in a stream of liquid nitrogen diffracted synchrotron X-rays to 0.2-nm resolution. PMID- 9370376 TI - Electron transfer towards the RCI-type photosystem in the green sulphur bacterium Chlorobium limicola forma thiosulphatophilum studied by time-resolved optical spectroscopy in vivo. AB - Flash-induced spectral changes in the wavelength region of the alpha-peaks of heme proteins and in the time domain from microseconds to seconds have been recorded on whole cells of the green sulphur bacterium Chlorobium limicola forma thiosulfatophilum. Extensive flash-excitation by trains of flashes resulted in oxidation of 7-8 c-type heme molecules/photosynthetic reaction centre. The complement of heme species was found to be spectrally heterogeneous allowing the study of electron transfer events induced by an isolated single-turnover flash. Under single-flash conditions, a c553 heme was seen to become oxidised with tau = 30 micros, concommitant with the reduction of the primary donor of the reaction centre. Subsequently, the alpha-peak of the photooxidised heme broadened and shifted towards longer wavelengths (tau = 70 micros) indicating equilibration of the positive charge over two differing heme species. In the time domain t > 1 ms, rereduction of c-type hemes was seen to be paralleled by a blue shift and further broadening of the alpha-peak. Concommitantly, b-type hemes were observed to first become reduced (within a few milliseconds), then over-oxidised (t > 200 ms) and eventually rereduced to their redox state prior to the flash. The results obtained are discussed with respect to the question of the identity of the immediate electron donor to the photosynthetic reaction centre and with respect to the involvement of a cytochrome bc complex in photo-induced electron transport of green sulphur bacteria. PMID- 9370377 TI - Impairment of endothelial function in salt-sensitive hypertension in humans. AB - In this study, we evaluated the relationship between the endothelium-dependent vasodilation and salt sensitivity in patients with essential hypertension. Fifteen untreated hypertensive male patients (age, 29 to 54 years) were sodium restricted (5 g/day) for 1 week, and placed on a high salt diet (20 g/day) the second week. At the end of each period, measurements of forearm vascular responses to drugs (acetylcholine, 3 to 24 microg/min; sodium nitroprusside, 0.15 to 1.2 microg/min; norepinephrine, 0.15 to 1.2 microg/min; and N(G)-monomethyl-L arginine [L-NMMA], 1 to 8 micromol/min) were obtained by using strain-gauge venous plethysmography. Subjects were divided into two groups according to the blood pressure response to sodium loading: salt-sensitive hypertensive group (24 h mean increase of arterial pressure > or = 10%; n = 6) and salt-resistant group (< 10%; n = 9). The two groups showed no significant difference in clinical data or mean arterial pressure during low salt intake. The dose-dependent vasodilation induced by acetylcholine was significantly reduced (P < .05) in the salt sensitive hypertensive patients v the salt-resistant patients regardless of sodium loading. There were no differences between the two groups in response to sodium nitroprusside, norepinephrine, or L-NMMA. These results indicate that vasodilation to acetylcholine is reduced in salt-sensitive hypertensive patients even on restricted sodium diets. This may contribute to blood pressure elevation when sodium intake is increased. PMID- 9370378 TI - Race affects the decline in blood pressure with hospitalization. AB - Hospitalization routinely lowers blood pressure (BP). This study examined the effects of race and psychologic characteristics on this phenomenon. Data are reported from two separate cohorts of hypertensive and normotensive black and white men and women who were studied following a stay at a clinical research center where sodium intake was held constant. Blacks (N = 88), as compared to whites (N = 77), showed consistently smaller declines in systolic BP (P < .01) following hospitalization (-11.6 mm Hg SBP v -19.5 mm Hg SBP, respectively). A multiple regression model that treated BP as a function of physiologic and psychologic attributes indicated that preadmission BP level, body mass index, stress level, and anger expression were related to the drop in systolic (r2 = 65%) and diastolic (r2 = 45%) BP brought about by hospitalization (P < .0001). In blacks, high environmental stress ratings were unrelated to the change in BP with hospitalization. In contrast, whites with high environmental stress ratings lowered their BP noticeably with hospitalization. Given that the reduction in BP with hospitalization can be similar to that attained with pharmacologic therapy, these findings may have a bearing on studies examining BP in the hospital. PMID- 9370379 TI - Awareness, treatment, and control of hypertension in Canada. AB - The Canadian Heart Health Surveys are cross-sectional, population-based cardiovascular disease risk factor surveys that took place in each of the 10 Canadian provinces between 1986 and 1992. Hypertension awareness, treatment, and control status are examined. Of 23,129 randomly selected, noninstitutionalized respondents aged 18 to 74 years, 85% had four blood pressure (BP) measurements taken under standardized conditions, two at home during a home interview and two at a following clinic visit. The mean of all available measurements was used to determine hypertension status. Estimates are weighted and represent population values. Only 2% of respondents had never had their BP checked, and 73% had had their BP checked in the last 12 months. A systolic or diastolic BP > or = 140/90 mm Hg was found in 22% of participants (26% of men, 18% of women), representing 4.1 million Canadians. Overall, 16% of participants were treated and controlled; 23% were treated and not controlled; 19% were not treated and not controlled; and 42% were unaware of their hypertension (47% of men and 35% of women). Among hypertensives 18 to 34 years old, 64% of men and 19% of women were unaware of their hypertension. Among treated and not controlled hypertensives 63% had a mean systolic BP > or = 150 mm Hg, and 29% a diastolic BP > or = 95 mm Hg, suggesting that an important number of Canadians treated for hypertension are still at increased risk. Despite frequent interactions with the health care system, too many Canadians are still not well controlled or are unaware of their hypertension. PMID- 9370380 TI - Effect of reduction of nitric oxide on plasma and kidney tissue angiotensin II levels. AB - Nitric oxide synthase (NOS) blockade increases blood pressure (BP) and modifies glomerular and tubular function. Angiotensin II (AII) blockade restores glomerular and tubular function but does not lower BP. We measured plasma renin activity (PRA), plasma (AIIp), and kidney tissue (AIIk) AII with radioimmunoassay to investigate the dissociation between renal and systemic effects of NOS blockade. Two period clearance studies followed by plasma and renal tissue harvesting were performed in seven groups of rats. Groups 1 and 1A served as controls. Groups 2 and 2A received NaCl-NaHCO3 during the first period and N(G) monomethyl-L-arginine (L-NMMA, 0.5 mg/kg/min) during the second period. Group 3 was similar to group 2 but renal perfusion pressure (RPP) was maintained constant by using an aortic snare. Groups 4 and 4A received N(G)-nitro-L-arginine-methyl ester (L-NAME, 5 mg/100 mL of drinking water) for 2 weeks. NOS blockers decreased AIIp (group 1, 74 +/- 7 pg/mL; group 2, 22 +/- 1 pg/mL; group 3, 26 +/- 1 pg/mL; group 4, 19 +/- 3 pg/mL). The decrease in AIIp was a direct effect of L-NMMA independent of changes in perfusion pressure, as AIIp was similar in group 3 (normal RPP) and groups 2 and 4 (increased RPP). Measurements of PRA and AIIp demonstrated a similar reduction in PRA and AIIp in rats treated with NOS blocker. Although NOS blockers decreased AIIp, acute or chronic administration of NOS blockers did not modify AIIk (group 1, 1,192 +/- 51; group 2, 1,354 +/- 85; group 3, 1,348 +/- 180; group 4, 1,276 +/- 172 pg/kidney). Our findings demonstrate that NO blockers produce a dissociation between plasma and kidney AII levels. This dissociation can explain the beneficial effects of AII blockers on renal function and their lack of antihypertensive effects in anesthetized rats treated with NOS blockers. PMID- 9370381 TI - Difference in susceptibility of developing renal damage in normotensive fawn hooded (FHL) and August x Copenhagen Irish (ACI) rats after N(omega)-nitro-L arginine methyl ester induced hypertension. AB - Previous studies using the fawn-hooded hypertensive (FHH) rat have indicated that genetic factors appear to be important in determining the susceptibility to develop renal damage. This was further investigated by comparing the effects of N(omega)-nitro-L-arginine methyl ester (L-NAME) induced hypertension on functional and structural renal damage in two normotensive strains, the resistant August x Copenhagen Irish rat (ACI) and the normotensive fawn-hooded (FHL) rat, which also appears to carry a susceptibility locus for renal failure. Male rats were studied during chronic treatment with L-NAME in either a low dose (LD, 75 to 100 mg/L drinking fluid) or a high dose (HD, 175 to 250 mg/L). Survival of FHL rats was adversely affected by L-NAME treatment. All FHL-HD and 6 of 14 FHL-LD rats died before the end of the 11 weeks of follow-up, whereas all treated ACI rats except for one ACI-HD animal survived. In both strains, L-NAME caused a dose dependent increase in systolic blood pressure (SBP). However, at similar levels of SBP, the increase in albuminuria (UaV) was significantly higher in FHL compared with ACI, as was the incidence of glomerulosclerosis (GS). Both the SBP and the blood pressure burden (SBP-Av), defined as SBP averaged over the period of follow-up, directly correlated with UaV and GS in both strains. However, the increase in the degree of renal damage per millimeter of mercury increase in SBP or SBP-Av was significantly higher in the FHL than in the ACI rats. Our findings clearly show that FHL rats are more susceptible to developing renal damage after induction of hypertension by chronic L-NAME treatment. We conclude that there is an interaction between blood pressure and the genetic susceptibility to renal disease in the FHL rat. PMID- 9370382 TI - Role of long-form PDGF A-chain in the growth of vascular smooth muscle cells from spontaneously hypertensive rats. AB - Vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) exhibit exaggerated growth relative to cells from normotensive Wistar-Kyoto (WKY) rats. Platelet-derived growth factor (PDGF) A-chain has been implicated in the exaggerated growth of VSMC from SHR. Two isoforms of PDGF A-chain mRNA that either include (long form) or exclude (short form) exon 6 are produced as a result of alternative splicing. The expression of the long-form PDGF A-chain at the mRNA level and its role in the growth of VSMC from SHR have now been investigated with the use of an antisense oligodeoxynucleotide (ODN) complementary to exon 6 of the PDGF A-chain gene. Reverse transcription polymerase chain reaction (RT-PCR) analysis with primers encompassing exon 6 of PDGF A-chain mRNA revealed bands corresponding to both long- and short-form PDGF A-chain transcripts in quiescent VSMC from both SHR and WKY rats, with the long form mRNA more abundant in VSMC from SHR than in cells from WKY rats. Expression of the long-form of PDGF A-chain mRNA was enhanced with angiotensin II and transforming growth factor-beta1 in VSMC from SHR, but not in cells from WKY rats. The antisense ODN significantly inhibited DNA synthesis by VSMC from SHR, but not by cells from WKY rats, in the absence or presence of serum. In addition, the antisense ODN significantly inhibited serum induced proliferation of VSMC from SHR, but not those from WKY rats. The antisense ODN abolished expression of the long-form PDGF A-chain mRNA in VSMC, suggesting that its inhibitory effects on the growth of VSMC from SHR are mediated by depletion of the long-form transcripts. These results indicate that the long-form of PDGF A-chain contributes to the exaggerated growth of VSMC from SHR. PMID- 9370383 TI - Inhibition of thromboxane synthesis attenuates insulin hypertension in rats. AB - Chronic insulin infusion in rats increases mean arterial pressure (MAP) and reduces glomerular filtration rate (GFR), but the mechanisms for these actions are not known. This study tested whether thromboxane synthesis inhibition (TSI) would attenuate the renal and blood pressure responses to sustained hyperinsulinemia. Male Sprague-Dawley rats were instrumented with arterial and venous catheters, and MAP was measured 24 h/day. After 4 days of baseline measurements, endogenous synthesis of thromboxane was suppressed in 7 rats by infusing the thromboxane synthetase inhibitor, U63557A, intravenously (30 microg/kg/min) for the remainder of the experiment; 7 other rats received vehicle. Baseline MAP was not significantly different between vehicle and TSI rats (96 +/- 1 v 99 +/- 1 mm Hg). After 3 days of U63557A or vehicle, a 5-day control period was started, followed by a 7-day infusion of insulin (1.5 mU/kg/min, intravenously). Glucose (22 mg/kg/min, intravenously) was infused along with insulin to prevent hypoglycemia. In the control period, MAP was not different between vehicle and TSI rats (99 +/- 2 v 100 +/- 1 mm Hg), but MAP increased throughout the 7-day infusion period only in the vehicle rats with an average increase in blood pressure of 7 +/- 2 mm Hg. In the control period, GFR was lower in vehicle rats compared with TSI rats (2.5 +/- 0.1 v 3.1 +/- 0.2 mL/min, P = .06), and the decrease to 81% +/- 4% and 91% +/- 6% of control, respectively, during insulin was significant only in the vehicle rats. All variables returned toward control during a 6-day recovery period. These results suggest that full expression of hypertension and renal vasoconstriction during hyperinsulinemia in rats is dependent on a normal ability to synthesize thromboxane. PMID- 9370384 TI - Tissue-specific regulation of the sodium pump in DOCA-salt hypertension. AB - Alterations in sodium pump activity have been associated with volume-sensitive hypertension, but little is known regarding the molecular regulation of the catalytically active alpha-subunit of the sodium pump in these models. We examined changes in the mRNA abundance of the alpha-isoforms in tissues that might participate in sodium and volume regulation in the deoxycorticosterone acetate (DOCA)-high salt rat model. These tissues included kidney, heart, aorta, pituitary, and hypothalamus. This study assessed alterations arising from changes in dietary salt intake alone, from DOCA administration alone, and those requiring both DOCA and high salt with their attendant volume expansion and hypertension. Increased sodium intake produced no significant change in any isoform in the five tissues studied. DOCA administered with a low salt diet produced no significant change in any of the alpha-isoforms in any of the tissues studied. The combination of DOCA and high salt (HS), on the other hand, brought about a twofold increase in renal alpha1-mRNA abundance compared with control (alpha1, CTL: 101.1 +/- 9.3, DOCA-HS: 197.3 +/- 22.9, P < .0001). DOCA-HS also induced a marked increase in both alpha1- and alpha2-mRNA in the aorta (alpha1, CTL: 122.5 +/- 33.3 v DOCA-HS: 487.2 +/- 59.9, P = .001; alpha2, CTL: 126.6 +/- 40.0 v DOCA HS: 559.8 +/- 271.7, P = .01). In contrast DOCA-HS animals showed a significant reduction in the alpha2-, but not alpha1-, mRNA abundance in heart (alpha2, CTL: 118.0 +/- 11.7 v DOCA-HS: 61.1 +/- 9.1, P = .006). No change was observed in pituitary or hypothalamus with DOCA-HS. Of factors known to modulate the mRNA abundance of the sodium pump, only the putative endogenous sodium pump inhibitor might account for the changes in the aorta and kidney. Reductions in aldosterone or hypertension might reduce alpha2 in the heart. Only the renal response would favor sodium reabsorption, which could contribute to the hypertensive process. PMID- 9370385 TI - In vivo platelet thrombus formation in microvessels of spontaneously hypertensive rats. AB - Sustained high blood pressure causes functional changes in both vascular endothelial cells and platelets. Therefore, we hypothesized that in vivo platelet thrombus formation would be increased in the cremaster muscle microvessels of rats during genetic hypertension. Experiments were carried out on spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto rats (WKY) at 12 weeks of age. Fluorescein isothiocyanate tagged to bovine serum albumin (FITC-BSA) was injected intraarterially and 450 to 490 nm light was used to activate the FITC BSA and induce a thrombus within the vasculature. In vivo television microscopy was used to quantitate thrombus formation and microvascular diameter changes. The time of platelet thrombus initiation and subsequent time of thrombus growth were studied at wall shear rates of approximately 2000 sec(-1) and 270 sec(-1) in third-order arterioles and venules, respectively. In SHR, times for platelet thrombus initiation and vessel occlusion were significantly less in both arterioles and venules, whereas time for platelet thrombus growth following initiation was significantly prolonged. Greater shear rates in arterioles compared to venules decreased platelet adhesion and subsequently decreased the rate of thrombus formation in both WKY and SHR groups. However, the ratio of WKY to SHR platelet thrombus growth (platelet aggregation) time remained similar (0.83 +/- 0.06 in arterioles and 0.79 +/- 0.06 in venules). These results indicate that there is increased thrombus formation during hypertension and that the platelet adhesion processes may be of greater importance than platelet aggregation in producing this increase. PMID- 9370386 TI - Quinapril inhibits c-Myc expression and normalizes smooth muscle cell proliferation in spontaneously hypertensive rats. AB - A number of data suggest that angiotensin II-dependent activation of the protooncogene c-myc participates in the proliferative response of smooth muscle cells (SMC) of rats with spontaneous hypertension (SHR). We therefore investigated the effects of chronic treatment with the angiotensin converting enzyme (ACE) inhibitor quinapril on the oncoprotein c-Myc and the proliferating cell nuclear antigen cyclin A in SMC of small intramyocardial arteries from the left ventricle of SHR. The expression of c-Myc and cyclin A was assessed by immunocytochemical analysis. The number of smooth muscle cells was assessed by morphometrical analysis. As compared to normotensive Wistar-Kyoto (WKY) rats, untreated SHR exhibited an increased percentages of cells expressing c-Myc (33% +/- 4% v 19% +/- 2%, mean +/- SEM, P < .005) and cyclin A (25 +/- 2 v 11% +/- 1%, P < .001). In quinapril-treated SHR compared with untreated SHR, we found decreased expression of c-Myc (22% +/- 2%, P < .005) and cyclin A (13% +/- 1%, P < .001). No significant differences were found between WKY rats and quinapril treated SHR in the above parameters. Cyclin A was directly correlated with the number of SMCs in each group of rats. These results suggest that an enhanced expression of c-Myc may be involved in the increased proliferation seen in SMCs from small arteries of SHR. Quinapril administration normalizes proliferation in the SMCs of SHR, possibly by inhibiting the expression of the oncoprotein c-Myc and its effects on the cell cycle. PMID- 9370387 TI - Calcium antagonism abolishes the antipressor action of vasopressin (V1) receptor antagonism. AB - Previous studies demonstrate that vasopressin (V1) receptor antagonism lowers arterial pressure in blacks. This action of V1 receptor blockade may be mediated through various mechanisms including changes in intracellular calcium fluxes. This study was undertaken to test the hypothesis that inhibition of calcium entry may attenuate the reduction in arterial pressure observed with V1 receptor blockade. Sixteen hypertensive patients, 8 whites and 8 blacks, were examined. Each had their antihypertensive therapy stopped for 1 week. Following three baseline blood pressure measurements, all patients were given an intravenous bolus injection of a V1 receptor antagonist. Blood pressure was monitored every 10 min for a period of 3 h. Subjects were then randomized to either 0.2 mg clonidine twice daily or 300 mg diltiazem CD daily for a period of 3 days and the previous experiments repeated. Patients were then crossed over to the other drug for an additional 3 days and the experiments repeated. There was a significant reduction from baseline in the mean arterial pressure among blacks but not whites (-11 +/- 3 delta mm Hg blacks versus -1 +/- 2 delta mm Hg whites, P < .01). In the presence of clonidine, there were similar reductions in arterial pressure in both groups (P = .026) with a further reduction following V1 receptor blockade only in the blacks (-7 +/- 3 delta mm Hg blacks versus 6 +/- 2 delta mm Hg whites; P < .001). Conversely, in the presence of diltiazem CD, there were no further reductions in arterial pressure in either group following the V1 receptor antagonist. We conclude that calcium channel blockade abolishes the blood pressure lowering response of V1 receptor blockade in blacks. PMID- 9370388 TI - Insulin resistance and hypertension: in vivo and in vitro insulin action in skeletal muscle in spontaneously hypertensive and Wistar-Kyoto rats. AB - The spontaneously hypertensive rat (SHR) has been reported to be insulin resistant compared to the Wistar-Kyoto (WKY) parent strain. Because insulin resistance usually reflects a defect in insulin action at the muscle, we compared the ability of muscle (gastrocnemius) to store glycogen in response to a standard oral glucose challenge in SHR to that in WKY. As a control, we examined the glycogen response in liver in these two rat strains. However, in vivo insulin action reflects both tissue responsiveness as well as substrate and hormone availability at the tissue level. To evaluate tissue responsiveness in vitro, we examined two parameters of insulin action: 1) muscle glycogen synthesis using 3H glucose and 2) muscle glucose transport using 3H-2-deoxy-glucose (3H-2-DG). Thirteen-week-old male rats were studied after overnight fasting. Liver glycogen increased similarly (mean +/- SD shown) in response to glucose gavage feeding in both groups [WKY: 15.2 +/- 6.9 to 50.6 +/- 17.9 micromol/g wet wt (P < .05); SHR: 30 +/- 18 to 63.5 +/- 33.3 micromol/g wet wt (P < .01)]. On the other hand, muscle glycogen increased in WKY [13.7 +/- 2 to 17.8 +/- 1.1 micromol/g wet wt (P < .05)], whereas in SHR there was no significant change [14.6 +/- 2.1 to 15.3 +/- 2.99 micromol/g wet wt P = NS)]. Results of in vitro studies demonstrated that glycogen synthesis increased from 377 +/- 120 to 439 +/- 175 disintegrations per minute (dpm) 3H-glucose/mg extensor digitorum longus (EDL) in WKY when insulin increased from 0 to 1000 microU/mL (P < .05), whereas SHR the increase was from 289 +/- 89 to 565 +/- 187 (P < .05). Glucose transport increased from 483 +/- 74 to 785 +/- 369 dpm 3H-2-DG/mg EDL in WKY when insulin was increased from 0 to 500 microU/mL (P < .03), whereas in SHR the increase was 516 +/- 61 to 997 +/- 347 (P < .001). In summary, liver glycogen increased in response to feeding in a similar manner in both WKY and SHR, whereas muscle glycogen increased only in WKY. We conclude that in vivo muscle glycogen accumulation may represent an index of insulin resistance in SHR. In contrast, in vitro data suggest that both muscle glucose transport and glycogen synthesis were stimulated to a comparable degree by insulin in EDL strips from WKY and SHR; there were no significant differences between WKY and SHR. Further studies are needed to clarify these differences. PMID- 9370389 TI - Dietary calcium attenuates platelet aggregation and intracellular Ca2+ mobilization in spontaneously hypertensive rats. AB - Spontaneously hypertensive rats (SHR) are known to be blood pressure sensitive to dietary calcium. The effects of dietary calcium on platelet aggregation and intracellular Ca2+ mobilization were assessed by turbidimetric methods and fura-2 methods, respectively, in washed platelets of SHR. Ca2+ ATPase activity was examined in aortic membrane fractions. Six weeks of dietary calcium supplementation attenuated the increase of systolic blood pressure (SBP 199 +/- 16 v 170 +/- 9 mm Hg, P < .001) and thrombin-induced platelet aggregation (84.5 +/- 3.7 v 73.7 +/- 7.4%, P < .004) at 9 weeks of age. The ionomycin-induced intracellular calcium ([Ca2+]i) peak in the absence of external Ca2+, which reflects [Ca2+]i storage size, and thrombin-evoked [Ca2+]i release from [Ca2+]i storage were decreased by 2.0% Ca diet (472 +/- 55 v 370 +/- 23 nmol/L, P < .001, 339 +/- 29 v 278 +/- 33 nmol/L, P < .002). In addition, SBP was positively correlated with platelet aggregation (r = 0.703, P = .0088), thrombin-evoked [Ca2+]i (r = 0.739, P = .0044), and ionomycin-induced [Ca2+]i (r = 0.591, P = .0415), respectively. However, there was no significant effect of dietary calcium on Ca2+-ATPase activity in aortic membranes. These results suggest that dietary calcium supplementation had a beneficial effect on platelets of SHR by attenuating [Ca2+]i mobilization from [Ca2+]i storage. The hypotensive effect of dietary calcium might be associated with attenuated [Ca2+]i mobilization in SHR. PMID- 9370390 TI - High plasma immunoreactive leptin level in essential hypertension. AB - Insulin resistance, the most important factor in metabolic syndrome X, has been considered to raise blood pressure. Recently it was reported that insulin resistance was related to an elevated plasma level of leptin, which is an adipocyte-specific ob gene product and which plays a role in food intake suppression, thermogenesis, and energy expenditure through the activation of the hypothalamus. However there are no reports that deal with the relationship of insulin resistance to plasma leptin and blood pressure. To evaluate the role of leptin in essential hypertensives, two groups of subjects who were carefully matched for body mass index (BMI) were studied; 22 normotensives (NT, age: 46.5 +/- 2.6 years, BMI: 23.9 +/- 0.4 kg/m2, male/female: 14/8) and 45 mild-to moderate essential hypertensives (EHT, age: 51.9 +/- 2.0 years, BMI: 24.5 +/- 0.4 kg/m2, male/female: 21/24). We applied the euglycemic hyperinsulinemic glucose clamp technique to all subjects and insulin sensitivity was evaluated as the M value. EHT showed a significantly lower M value (160.2 +/- 7.4 v 184.3 +/- 7.3 mg/m2/min, P < .05) and higher basal plasma immunoreactive leptin level (7.6 +/- 0.8 v 5.0 +/- 0.8 ng/mL, P < .05) than NT, despite the fact that there was no significant difference between NT and EHT in age, gender, or BMI. The relationship between mean blood pressure and leptin showed a significant positive correlation in all of the subjects (r = 0.31, P < .05), suggesting that leptin may be related to a pathophysiology of essential hypertension. PMID- 9370392 TI - Comments on the study of Zannad et al. Monitoring to evaluate antihypertensive therapy. PMID- 9370393 TI - Functional improvements in ventilatory mechanics after lung volume reduction surgery for homogeneous emphysema. AB - OBJECTIVE: Between September 1994 and August 1996 Lung Volume Reduction Surgery (LVRS) was performed through median sternotomy, videoendoscopically or by thoracotomy in 54 consecutive patients (age 34-69 years, mean 48 years). METHODS: The areas with the most destroyed lung parenchyma were resected by means of linear stapling devices. A total of 5 patients died postoperatively due to aspiration pneumonia, multiorgan failure and acute hepatic failure respectively. A marked functional improvement and increase in quality of life was observed in the remaining patients. RESULTS: Residual volume decreased from 317.0 +/- 12.4% of predicted (%p) preoperatively to 226.2 +/- 8.8%p within the first month (P = 0.0001). FeV1 significantly increased from 23.7 +/- 1.3%p preoperatively to 36.3 +/- 4.1%p during the first 6 months postoperatively (P = 0.0016). Radiological signs of hyperinflation and distention of the thorax preoperatively improved to a more dome shaped diaphragm and narrowed intercostal spaces. These morphologic changes resulted in better ventilatory muscle function. The intrinsic PEEP significantly decreased from 5.92 +/- 0.64 cm H2O preoperatively to 1.70 +/- 0.25 cm H2O postoperatively (P = 0.0001). The work of breathing decreased from 1.58 +/ 0.09 J/l preoperatively to 0.99 +/- 0.07 J/l postoperatively (P = 0.0001). CONCLUSIONS: In conclusion, LVRS is an excellent therapeutic option for patients with homogeneous emphysema with additional signs of severe hyperinflation. PMID- 9370391 TI - Vascular compliance and cardiovascular disease: a risk factor or a marker? PMID- 9370394 TI - Role of surgery in multi-drug-resistant tuberculosis: results of 27 cases. AB - OBJECTIVE: To evaluate the results of resectional surgery as an adjuvant therapy in multi-drug resistant tuberculosis. METHODS: A total of 27 human immunodeficiency virus (HIV)-negative patients with multi-drug resistant tuberculosis underwent resectional surgery between 1993 and 1996. The lesions were bilateral in 16 cases, with a preponderance of cavities on one side. Out of 27 cases, 5 patients had unilaterally destroyed lung; 20 patients underwent pneumonectomy (15 left, 5 right). Lobectomy operations included bilobectomy superior (n = 1), right lower lobectomy (n = 2), right upper lobectomy (n = 3), and left upper lobectomy with superior segmentectomy (n = 1). RESULTS: Because of haemorrhage, 2 cases who underwent a right and left pneumonectomy, respectively, required revision on the first day . Bronchopleural fistula was found in 2 cases with left pneumonectomy. Apical residual space was left in one of the 3 patients who underwent right upper lobectomy. Retreatment protocols resulted in negative cultures and smears in all patients with an average duration of 4 months (1-6 months). A total of 4 patients (16%) completed a retreatment period of 18-24 months with negative cultures. Only 1 patient (3.7%) developed relapse in the 17th month of retreatment. Patients with negative cultures numbered 22 and continued receiving retreatment. CONCLUSIONS: Our results indicate that surgical management of multi-drug resistant tuberculosis, combined with chemotherapy, provides a more favourable outcome than that obtained with medical therapy alone. PMID- 9370395 TI - Tumor angiogenesis and biologic markers in resected stage I NSCLC. AB - OBJECTIVE: Microvessel count (MC), as a measure of tumor angiogenesis, has been shown to be significantly correlated with metastatic disease in cutaneous, mammary, prostatic, head and neck cancer. We have previously assessed the role of intensity of angiogenesis as predictor of metastasis in surgically resected T1N0M0 NSCLC. We needed to confirm its value, in a prospective larger study on Stage I NSCLC, before its utilization as a prognostic tool for further clinical investigations. METHODS: In the present report we prospectively investigated 227 patients (206 males, 21 females; median age 65 years) with Stage I NSCLC treated only by radical surgery between March 1991 and December 1994 with utmost care for some biological characteristics (proliferative activity, the blood vessel invasion, angiogenesis and the p53 protein expression). RESULTS: The operative procedures consisted of 62 pneumonectomies, 148 lobectomies and 17 segmentectomies or wedge resections. With a median follow-up of 36 months (range 15-60), eighty patients have already experienced a local (n = 22) or systemic (n = 58) relapse. Univariate analysis revealed that T factor (T1 versus T2)(P = 0.008) and angiogenesis count (< or = versus > median, 17) (P = 0.0006) were significant predictors of survival. The same variables were also significant predictors of long Disease Free Survival (P = 0.006 and P = 0.004, respectively). On multivariate analysis, however, only the microvessel count retained its level of prognostic significance as regards both overall (P < 0.01) and disease-free survival (P < 0.01). CONCLUSIONS: The present study corroborates the role of angiogenesis in the metastatic spread of NSCLC and emphasizes its value in the identification of patients in whom surgery should be supplemented by systemic treatment. PMID- 9370396 TI - Experimental assessment of photodynamic therapy with chlorins for malignant mesothelioma. AB - OBJECTIVE: Photodynamic therapy (PDT) with two chlorin sensitisers was assessed on nude mice bearing human mesothelioma xenografts, and on intrathoracic tissues of minipigs with the same drug-light conditions to optimise the antitumour activity of PDT while preventing photosensitising injury to normal tissues. METHODS: Laser light (20 J/cm2) at 652 nm was delivered to the xenografts 1-4 days after i.p. administration of 0.1 mg/kg m-tetrahydroxyphenyl-chlorin (mTHPC) or an equimolar dose of polyethylene glycol-derived mTHPC (pegylated mTHPC), respectively. The extent of tumour necrosis was assessed by histomorphometry. Intraoperative PDT was then performed to the thoracic cavity of minipigs through a sternotomy with the same drug-light conditions at drug-light intervals ranging from 12 h to 6 days after i.v. administration of mTHPC and pegylated mTHPC, respectively. RESULTS: Both, mTHPC and pegylated mTHPC, resulted in photosensitised necrosis of mesothelioma xenografts at drug-light intervals from 1 to 4 days but the extent of necrosis was significantly larger by use of pegylated mTHPC instead of mTHPC at a drug-light interval of 3 and 4 days. The optimal tumourcidal effect was achieved with pegylated mTHPC at a drug-light interval of 4 days. The photosensitising effect of mTHPC on intrathoracic tissues of minipigs revealed severe damage of virtually all tissues except nerves at short drug-light intervals. Tissue damage gradually became less at longer drug light intervals and was absent at intervals of 3 days and longer. In contrast, pegylated mTHPC resulted in no obvious change to any structure at any drug-light interval assessed. CONCLUSIONS: PDT with pegylated mTHPC reveals the potential of selective tumour destruction in this experimental setting and deserves further evaluation for intraoperative application in patients with malignant mesothelioma. PMID- 9370397 TI - The role of cryotherapy for airway complications after lung and heart-lung transplantation. AB - OBJECTIVE: Although airway problems after lung and heart-lung transplantation have been greatly reduced due to changes in surgical technique, excessive granulation tissue at the anastomosis may threaten airway patency. Treatment options include electrocautery, dilation, laser coagulation and stent placement however, recurrence remains a problem. Cryotherapy, the controlled application of extreme cold, is effective at causing cell lysis in granulation tissue and may therefore be effective after lung transplantation for airway problems arising from granulation stenosis. Our objective was to review our experience with cryotherapy as a first-line treatment for airways compromised by granulation tissue after lung and heart-lung transplantation. METHODS: A retrospective analysis of patient records after lung and heart-lung transplantation was performed. A total of 696 patients were identified who received lung or heart lung transplants, 64 of whom were found to have granulation tissue at the site of airway anastomosis (8.9% of 721 airways at risk). When the granulation tissue was found to narrow the lumen by > or = 50% and affect lung function. RESULTS: The trachea was involved in 5 patients and the main stem bronchus in 16. Each patient required a mean of 2.6 +/- 2.0 cryoapplications. Anatomical results of cryotherapy were judged excellent to good in 15 patients and fair in 6 patients. Eight patients required endobronchial stenting as part of a multimodality treatment. Overall, the post-treatment FEV1 and FVC increased by 34 +/- 36% and 25 +/- 27% from pre-treatment values respectively (P < 0.001). In 13 patients in whom cryotherapy and dilation alone were effective, the FEV1 increased by 41 +/- 43% (range -11 +/- 138%) and the FVC by 28 +/- 29% (range -4 +/- 96%). These changes were also significant (P < 0.001). Changes in these two parameters were positively and significantly correlated (P < 0.01). Acturial survival at 3 and at 5 years were 57 and 43%, respectively (NS compared to total cohort), and median survival was 978 days (range 365-1862). Six patients are alive at a median follow up of 5.75 years (range 0.6-8.3). CONCLUSIONS: We conclude that cryotherapy is a safe, effective treatment for excessive granulation tissue after lung and heart lung transplantation and may reduce the need for endobronchial stenting and limit recurrence. PMID- 9370398 TI - Conventional and total orthotopic cardiac transplantation: a comparative clinical and echocardiographical study. AB - OBJECTIVE: Clinical interest has recently emerged in a new technique of heart transplantation with bicaval and pulmonary venous anastomosis. This technique is thought to improve left heart function and reduce thromboembolism. We have used this technique systematically since 1993. We compared the patients transplanted before September 1993 with the standard technique and the patients transplanted with the new technique. METHODS: A total of 135 patients were transplanted at our institution from 1987 to 1995, 100 with the standard technique and 35 with the new technique. of these, 95 survivors were studied by transthoracic and transesophageal echocardiography; 65 were transplanted with the standard technique ('standard' group) and 30 with the new technique ('total heart' group). All patients were free from rejection and in sinus rhythm when studied. RESULTS: Boths groups were similar in pretransplant characteristics. Operative data were similar with a limited increase in the ischemic time with the total heart technique (210 +/- 73 min for 'total heart' vs. 196 +/- 84 min for 'standard'). Right heart catheterization showed comparable cardiac output and pulmonary pressures. Peripheral embolic events occured in 9 patients in the 'standard' group and none in the 'total heart' group. The left atrium was larger in the 'standard' group (58 +/- 6 vs. 42 +/- 4 mm, P = 0.0006). Left atrial spontaneous echo contrast was present in 32 patients in group 'standard' and none in 'total heart' group (P < 0.0001), and left atrial thrombi were detected in 17 patients in group 'standard' vs. none in group 'total heart' (P = 0.01). All patients with a history of embolism had left atrial thrombus and spontaneous echo contrast. CONCLUSION: This study showed a high incidence of left atrial spontaneous echo contrast and thrombi when using the standard technique, which was absent when using the total heart technique. Total heart transplantation with bicaval and pulmonary venous anastomosis should be preferred for heart transplantation. PMID- 9370399 TI - Dynamic cardiomyoplasty: clinical follow-up at 12 years. AB - OBJECTIVE: The purpose of this study is to evaluate the long-term outcome of dynamic cardiomyoplasty. This surgical technique was conceived to assist the failing heart. The many proposed mechanisms of action of cardiomyoplasty are: (1) systolic assist; (2) limitation of ventricular dilation; (3) reduction of ventricular wall stress (sparing effect); (4) ventricular remodeling with an active girdling effect; (5) angiogenesis; and (6) a neurohumoral effect. METHODS: We investigated 95 patients in our hospital undergoing this procedure due to severe chronic heart failure, refractory to optimal medical treatment. Patients had a mean age of 51 +/- 12 years. The etiology of heart failure was ischemic 55%, idiopathic 34%, ventricular tumor 6%, and other 5%. The mean follow-up was 44 months. RESULTS: The mean New York Heart Association (NYHA) functional class improved postoperatively from 3.2 to 1.8. Average radioisotopic left ventricular (LV) ejection fraction increased from 17 +/- 5 to 27 +/- 4% (P < 0.05). Stroke volume index increased from 32 +/- 7 to 43 +/- 8 ml/beat per m2 (P < 0.05). The heart size remained stable over the long term. Following cardiomyoplasty, the number of hospitalizations due to congestive heart failure was reduced to 0.4 hospitalizations/patient per year (preoperative: 2.5, P < 0.05). Computed tomography scans showed at long term a preserved latissimus dorsi muscle structure in 84% of patients. Survival probability at 7 years is 54%. Six patients underwent heart transplant after cardiomyoplasty (mean delay: 25 months), due to the natural evolution of their underlying heart disease. There were no specific technical difficulties. CONCLUSIONS: Clinically, this procedure reverses heart failure, improves functional class and ameliorates quality of life. The latissimus dorsi muscle histological structure is maintained at long term, when postoperative electrostimulation is performed, avoiding excessive stimulation. Cardiomyoplasty may delay or prevent the progression of heart failure and the indication of cardiac transplantation. PMID- 9370400 TI - Increased pulmonary flow velocities in oversized homografts in patients after the Ross procedure. AB - OBJECTIVE: Between September 1991 and July 1996, 60 patients (mean age 29.8 +/- 9 years; range 5-57) underwent aortic root replacement with pulmonary autograft, a viable biologic and nondegenerating substitute. The pulmonary root was replaced with cryopreserved homografts from cardiac transplant recipients. The aim of this study was to evaluate differences in early valve function of viable and cryopreserved allografts. METHODS: All patients had Doppler echocardiographic examinations preoperatively, at discharge from hospital and 54 patients at 1 year follow-up. We measured aortic and pulmonary peak flow velocities with continuous and pulsed-wave Doppler, and graded aortic and pulmonary insufficiency (AI, PI) with color Doppler flow (grade 0-IV). Intraoperatively, the diameters of the pulmonary root and the pulmonary homograft were measured with standard valve probes and matched to body surface area. RESULTS: Pulmonary peak flow velocity (PVmax) increased significantly from preoperative 0.87 +/- 0.11 m/s to 1.30 +/- 0.34 m/s postoperatively (P < 0.001). The implanted homografts (mean 25.9 +/- 2.4 mm) were larger than their native pulmonary diameter (mean 23.3 +/- 1.8 mm) in all patients. Homograft size matched for body surface area (BSA) did not correlate with increased PVmax. There was a significant increase of PVmax at follow-up (FU) since discharge, also (1.83 +/- 0.53 m/s; P < 0.001). Pulsed-wave Doppler demonstrates that increase of PVmax is located directly at the homograft leaflets and not at the anastomoses. Aortic peak flow velocities (AVmax) were normal postoperatively and at FU (post = 1.35 +/- 0.35 m/s; FU = 1.17 +/- 0.27 m/s). There was no significant change in AI or PI since discharge (AI FU = 0.8 +/ 0.4; PI FU = 0.7 +/- 0.5). Eight patients with fever and symptoms diagnosed as post-pericardiotomy syndrome had significantly higher PVmax at FU (PVmax = 2.41 +/- 0.40 m/s; P < 0.02). CONCLUSIONS: The Ross procedure leads to normal AVmax but significant increase of PVmax even in oversized cryopreserved homografts immediately after surgery. Further increase of PVmax without changes in AVmax in the first year demonstrates that changes in flow velocities are valve related and not due to increase in cardiac output. Further investigations will be necessary to determine whether this observation is due to valve rejection or early leaflet degeneration and treatment with immunosuppressive therapy is warranted. PMID- 9370401 TI - Exercise capacity and mid-term survival in patients with tricuspid atresia and complex congenital cardiac malformations after modified Fontan-operation. AB - OBJECTIVE: Continued follow-up of the Fontan population group is mandatory in order to evaluate the best approach for long term treatment. We studied exercise capacity and survival in patients with either right atrial to right ventricular (Fontan-Bjoerk, RA-RV) anastomosis or right atrial to pulmonary artery (RA-PA) connection. METHODS: Between January 1980 and December 1995 Fontan-Bjoerk modifications were performed in 73 patients with tricuspid atresia. A RA-PA anastomosis (performed either with direct atrio-pulmonary connection or with a lateral tunnel of autologous atrial tissue) was used in 118 patients with single ventricle or complex cardiac malformations. Using bicycle ergospirometry and impedance cardiography standard variables of exercise testing were measured in 15 patients with RA-RV and in 18 patients with RA-PA connection. A group of 23 healthy pupils served as controls. RESULTS: Follow-up was complete for 97.9% (n = 187) of all operated patients. Survival (% mean +/- SEM) at 5, 10 and 15 years was 89.3 +/- 3.6, 76.8 +/- 0.6 and 63.6 +/- 10.5 for RA-RV connection and 80.2 +/ 4.0, 75.3 +/- 4.5 and 64.6 +/- 10.7 for RA-PA connection (P = 0.12) respectively. Exercise capacity was tested after a median time of 6.0 (0.8-19.8) years after Fontan operation in RA-RV and of 7.8 (4.3-18.2) years in RA-PA patients. Total work load was equal in the two Fontan groups, but it was below normal. Heart rate, respiratory rate, oxygen uptake and ventilatory equivalent for oxygen were not different between the two Fontan groups. Cardiac index and stroke volume index were consistently lower at anaerobic threshold and at maximal exercise in RA-PA patients compared with controls. CONCLUSION: Survival analysis between RA-RV and RA-PA Fontan connection failed to demonstrate a better outcome for patients with either Fontan modification. Although there was a tendency for RA-RV connection to adapt cardiac output more efficient to exercise compared with RA-PA patients, total work load and ventilatory equivalent was not significantly different between the two Fontan modifications. We conclude, that by incorporation of a residual subpulmonary ventricular chamber within the Fontan circulation no additional benefit for exercise capacity could be observed. PMID- 9370402 TI - Pulmonary circulation after biventricular repair in patients with major systemic to-pulmonary collateral arteries. AB - OBJECTIVE: To determine factors affecting postoperative pulmonary circulation in patients with major systemic-to-pulmonary collateral arteries. METHODS: A total of 48 patients underwent biventricular repair subsequent to unifocalization at ages in the range 1-34 years. The preparative procedures consisted of ligation of the collateral arteries in 6, plasty to the pulmonary arteries using no artificial materials in 12 and extensive reconstruction using heterologous pericardial tubes in 30. The number of the pulmonary vascular segments unifocalized was 9-18 (16 +/- 3). The amount of flow draining via residual minute systemic-to-pulmonary collaterals measured at the time of repair was 4-58% (24 +/ 16%) of the total perfusion by the cardiopulmonary bypass machine. RESULTS: This value was 40 +/- 16% in 5 patients dying in the short term after repair. The number of segments was nine or ten after unifocalization in 2 of these. Another 4 patients died in the longer term, 3 of these with CATCH 22 syndrome dying because of pulmonary hypertension. Postoperative catheterization demonstrated mean pulmonary arterial pressures in the range 8-40 (21 +/- 9) mmHg and pulmonary resistance in the range 1.7-10 (5.0 +/- 2.1) units/m2. Pulmonary resistance was correlated statistically to age at repair (r = 0.77), the number of pulmonary vascular segments (r = -0.41) and to percent collateral flow (r = 0.48). The use of a heterologous pericardial tube for unifocalization was also related probably to higher pulmonary resistance. CONCLUSION: It is essential to accomplish effective unifocalizations followed by earlier definitive repair so as to establish better pulmonary circulation. PMID- 9370403 TI - The morphologically tricuspid valve in hypoplastic left heart syndrome. AB - OBJECTIVE: Competence of the tricuspid valve is crucial for survival of children with hypoplastic left heart syndrome. We studied the morphology and topology of the valvar and subvalvar structures, trying to identify abnormalities which could impair valvar function. METHODS: A total of 82 specimens with hypoplastic left heart syndrome were examined pathologically. Measurements of valvar dimensions were taken, significant dysplasia of the valvar leaflets was noted and the muscular and tendinous supporting structures determined. The findings were correlated to the subgroups of hypoplastic left heart syndrome. RESULTS: Of the hearts, 10 (12%) showed a bileaflet right atrioventricular valve, 27 (33%) a moderately and 2 (2%) a severely dysplastic tricuspid valve. The majority of the abnormalities was found in hearts with a patent mitral valve. In 79% of the hearts with mitral atresia, the septal surface was concave instead of convex to the right ventricular lumen and the direct tendinous attachments of the septal leaflet replaced by a multitude of freestanding papillary muscles. The number of direct septal attachments was significantly higher in hearts with a patent mitral valve. CONCLUSIONS: The tricuspid valve in hypoplastic left heart syndrome can differ from the valve seen in normal patients. The subvalvar apparatus is different in hearts with mitral atresia, whereas dysplasia of the leaflets occurs more often together with mitral stenosis. These features should be considered in reconstructive operations as well as during diagnostic procedures. PMID- 9370404 TI - Cardiological and general health status in preschool- and school-age children after neonatal arterial switch operation. AB - OBJECTIVE: Cardiological and general health status 3-9 years after neonatal arterial switch operation for transposition of the great arteries should be evaluated by non-invasive methods. METHODS: A total of 77 unselected children with intact ventricular septum (75.3%) or ventricular septal defect (24.7%) without or with aortic isthmic stenosis (5.2%) were prospectively examined 3.2 9.4 years (5.4 +/- 1.6) after neonatal switch. Clinical pediatric and cardiological examination, standard and 24 h Holter electrocardiogram, M-mode, 2D , Doppler and colour Doppler echocardiography were performed. Outcome data were compared to published normals. RESULTS: Reoperation rate was 2.6%, 96.1% were without limitation of physical activity and 98.7% without medication. Compared to normals, growth was adequate, weight and head circumference were slightly reduced. After median sternotomy, 23.4% had abnormal thoracic configuration (16.9% asymmetry, 6.5% funnel chest). ECG and Holter: 93.5% were in sinus, 6.5% in ectopic atrial or junctional rhythm. Incidence of complete right bundle branch block was 15.8% in patients with ventricular septal defect and 5.2% in those without. Ischemic ST-T changes during exercise due to coronary artery occlusion and evidence of old myocardial infarction were found in 1 patient (1.3%) each. Occasional atrial ectopy was found in 27.4%, ventricular ectopy in 15.3%: occasional in 12.5% and frequent (> 30/h) in 2.8% presenting bigemini, couplets and short runs of ventricular tachycardia at rest and during exercise. Echocardiography: Left ventricular function was normal in all. Endsystolic diameter of neoaortic valve annulus was beyond 90% confidence interval for controls in 79.2%, neoaortic root diameter in 100%. Mild aortic insufficiency was seen in 10.4%. No correlation was found between aortic insufficiency and aortic dilatation. Neoaortic stenosis was not seen, mild residual coarctation after end to-end-anastomosis was found in 2.6%, native coarctation corrected later on in 1.3%. Supravalvular pulmonary stenosis was seen in 29.9% (19.5% trivial, 7.8% mild, 2.6% moderate), mild subvalvular pulmonary stenosis in 1.3%, pulmonary insufficiency in 2.6%. CONCLUSION: The study confirms good midterm results after neonatal arterial switch operation for transposition with or without ventricular septal defect. Long-term observation is necessary to assess rhythm, coronary artery and myocardial function as well as development of neo-aorta and pulmonary artery system. PMID- 9370405 TI - Heart surgery and quality of life: a prospective study on ischemic patients. AB - OBJECTIVE: Recently, an interest has developed in the use of quality of life instruments to provide a more comprehensive assessment of the impact of disease and treatments on patients' everyday lives over time, particularly in the cardiovascular field. To evaluate changes in quality of life of patients with a coronary heart disease and undergoing heart surgery and to identify patients on which to concentrate stronger rehabilitative intervention, an observational prospective study with repeated measurements has been designed. METHODS: A total of 259 consecutive coronary heart disease patients (211 males, 48 females, aged 63 (S.D., 9 years) are included into the study. Quality of life has been assessed by means of Karnofsky Performance Status Scale and Nottingham Health Profile (6 dimensions of quality of life) preoperatively, at 2 and 6 months. Changes in quality of life scores at short and mid term and the influence of possible predictors have been investigated. Separate scores have been considered for each dimension of quality of life as well as a global statistics accounting for the multidimensionality of quality of life. RESULTS: Quality of life increased by 57, 64, 72, 52, 23, 44 and 56% for Karnofsky Performance Status Scale, energy, pain, emotion, sleep, social and mobility respectively at 2 months; at 6 months a further increase of 18% in sleep only occurred. Global scores appeared to be significantly influenced by sex, age class, preoperative NYHA, type of angina, associated procedure and complication at surgery. CONCLUSIONS: The increase of quality of life concentrates mainly at an early stage of post-operative period. The preoperative factors tested, allow to stratify patients based on quality of life and to identify those on which to concentrate stronger rehabilitative intervention. PMID- 9370406 TI - Quality of life after coronary bypass grafting: do bigger hospitals give better outcomes? PMID- 9370407 TI - Impact of coronary artery bypass grafting on various aspects of quality of life. AB - OBJECTIVE: To prospectively study the improvement in quality of life (QoL) after coronary artery bypass surgery (CABG). PATIENTS AND METHODS: Consecutive patients (n = 2121) who underwent CABG at Sahlgrenska University Hospital between 1988 and 1991 received 3 questionnaires for the study of QoL: the Physical Activity Score, the Nottingham Health Profile and the Psychological General Well-being Index, which were responded both before surgery and at 3 months (n = 1059), 1 year (n = 1045) and 2 years (n = 1027) postoperatively. RESULTS: All differences were tested against baseline. The Physical Activity Score improved (mean 4.3 before CABG, 3.1, 3 months after (P < 0.0001), and 2.8, 2 years postoperatively (P < 0.0001)). The Nottingham Health Profile score improved (mean 20.5 before CABG, 11.4, 3 months (P < 0.0001), and 10.4, 2 years postoperatively (P < 0.0001)). The Psychological General Well-being Index improved (mean 91.1 before CABG, 103.8, 3 months (P < 0.0001), and 105.8 (P < 0.0001), 2 years after CABG). The subscale analyses of the Nottingham Health Profile and the Psychological General Well being Index 2 years after CABG showed the greatest improvement in areas reflecting physical capacity and pain, to be followed by mental qualities. At 2 years after CABG only sexual problems were still markedly frequent, and independent predictors for sexual problems after surgery were preoperative problems (P < 0.00001), male sex (P < 0.0001), and diabetes mellitus (P = 0.0008). CONCLUSION: QoL was markedly and significantly improved after CABG. The major improvement was seen already at 3 months, with further slight improvement observed 2 years after surgery. The major improvement was found in areas reflecting physical capacity and pain, which is consistent with symptomatic and objective measurements after CABG. In contrast to the overall improvement in QoL sexual problems were still markedly common 2 years after CABG. The mechanism for this is not fully understood and needs further investigation. PMID- 9370408 TI - Comparison of retrograde versus antegrade cold blood cardioplegia: randomized trial in elective coronary artery bypass patients. AB - OBJECTIVE: Myocardial areas distal to complete coronary artery occlusion are poorly protected by antegrade cardioplegia. Hence, retrograde cardioplegia becomes an important adjunct in myocardial protection. An aim of the study was to compare both methods prospectively. METHODS: 158 coronary artery bypass grafting (CABG) patients were randomly assigned to two groups according to myocardial protection technique: 89 patients to group 1--retrograde cold blood cardioplegia (RCBC); and 69 patients to group 2--antegrade cold blood cardioplegia (ACBC). Preoperative parameters were similar but cross-clamp time and volume of cardioplegia needed were higher in the retrograde group. The results were assessed on the basis of: (1) clinical outcome; (2) ECG and enzymatic parameters of ischemia; (3) assessment of early systolic function by means of cardiac output (CO), stroke work index (SWI), left ventricular stroke work index (LVSWI) and right ventricular stroke work index (RVSWI) taken before, and 1 and 5 h after coming off bypass; (4) late systolic and diastolic function by echo assessment of segmental contractility of 17 segments and indexes of peak transmitral flow (TMI) taken 7 days and 6 months after operation. RESULTS: Ischemic events, inotropes and ventricular fibrillation on reperfusion were significantly more frequent in the antegrade group. Sinus rhythm at an early stage postoperatively was found more frequently in the retrograde group. All these parameters became comparable 24 h after operation. Early myocardial recovery was better in the retrograde group where intraoperative improvement in CO and SWI was significant. At the same time, SWI decreased significantly in the antegrade group. RVSWI changes were similar in both groups. There were no differences in mortality and perioperative MI. Late myocardial performance by segmental contractility and diastolic transmitral flow were similar in both groups. CONCLUSIONS: Retrograde continuous blood cardioplegia reduces ischemic injury and permits better early recovery of myocardial function. There is no difference, however, regarding long-term assessment of myocardial recovery. PMID- 9370410 TI - Platelet morphology in patients with mechanical circulatory support. AB - OBJECTIVE: Mechanical circulatory support is a therapy for patients with end stage cardiac insufficiency. The thromboembolic events are feared complications during support, due to the surface thrombogenicity of the implanted device. Activated blood platelets play a major role in this context. Consequently the platelet morphology of patients was investigated. METHODS: Platelets of eight patients were observed by means of scanning electron microscopy during the period of support with the Novacor left ventricular assist system N100. Blood was collected preoperatively and daily during the first week as well as weekly during the first 3 months. Samples were fixed with cacodylic-acid buffered glutaraldehyde. Platelet alterations were classified as non-activated, activated and aggregated, based on the so-called 'shape change' morphology. In addition, blood coagulation parameters were evaluated (e.g. activated partial thromboplastin time, prothrombin time, antithrombin III). RESULTS: Preoperatively, 15.0 +/- 4.6% (overall mean values) of activated platelets were found. Within the first postoperative week, the mean level of activated platelets increased to 32.8 +/- 8.0% (P < 0.05). Comparing short- (< 30 days; n = 4) vs. long-period (> 30 days; n = 4) support, a significant difference of activated platelets was evaluated (24.3 +/- 3.3% vs. 34.8 +/- 3.4%, P = 0.004). A correlation was found between the values of activated clotting time and activated platelets. Specific platelet deformations and damages appeared during support, which could not be found preoperatively. CONCLUSIONS: The platelet morphology showed alterations in all patients probably most strongly induced by the surface activation of the implanted device. These observations should be taken into consideration in management of postoperative anticoagulation therapy. PMID- 9370409 TI - Intraoperative radiofrequency microbipolar coagulation to replace incisions of maze III procedure for correcting atrial fibrillation in patients with rheumatic valvular disease. AB - OBJECTIVE: Radiofrequency catheter ablation of atrial tachycardias and flutter is an established technique. The same modality in the microbipolar mode is effective in producing full thickness coagulation injury. Cox's maze procedure is highly successful in curing atrial fibrillation (AF) surgically. However, it consumes relatively long cross clamp time and cardiopulmonary bypass time. In this study, radiofrequency microbipolar coagulation was used as an adjunct to corrective valve surgery, as an intraoperative ablative modality to replace Cox's maze III incisions, thus remarkably shortening the procedure. The results of this procedure are compared historically with those of 26 patients who underwent corrective valve surgery alone. METHODS: Radiofrequency microbipolar coagulation was used to produce conduction blocks along the Cox's maze III incision lines as an adjunct to valve surgery in 18 patients in atrial fibrillation undergoing surgery for rheumatic valvular disease. A bayonet type bipolar forceps with an active tip length of 7 mm drawing current from a microbipolar port of Valleylab Force 4 electrosurgical unit (Valleylab, Boulder, CO) was used for microbipolar coagulation. A 3-mm retinal handheld cryoprobe working on nitrous oxide gas was used for cryoablation. RESULTS: A total of 15 survivors in the coagulation maze group were followed from 43 to 224 days (149.7 +/- 73.1 mean +/- S.D.). Twelve of the 15 survivors (80%) converted to normal sinus rhythm (70% confidence limit: 64.7-90.6%). Atrial transport function studies with pulsed wave doppler, showed presence of a wave in all the 12 (100%) patients in tricuspid valve flow and in nine (75%) patients in mitral valve flow. The procedure took 11.62 +/- 3.86 min of elective cardioplegic arrest time for the left atrial portion and 18.71 +/- 4.25 min of cardiopulmonary bypass time during reperfusion for the right atrial portion. Of the 23 survivors out of 26 patients who underwent the valve procedure alone, only one patient (4.3%) converted to normal sinus rhythm (70% confidence limit: 0.6-14%). CONCLUSION: Thus, our modification considerably shortened the time taken for creating the maze in comparison to the Cox's maze procedure and was effective in restoring normal sinus rhythm in 80% of the patients. PMID- 9370411 TI - The effects of simulated akinetic and dyskinetic aneurysms on left ventricular systolic function: clinical implications. AB - OBJECTIVE: Scant attention has been directed towards quantifying the degree of mechanical disadvantage produced by akinetic and dyskinetic aneurysms. The purpose of this study was to evaluate the mechanical disadvantages of simulated akinetic and dyskinetic aneurysms on left ventricular function. METHODS: An elaborate experimental apparatus consisting of a computer-controlled water pressure chamber in which is suspended a model rubber ventricle was developed. The system has been shown to reproduce accurately the ventricular and aortic pressures found in vivo. In this study, a procedure was designed to simulate akinetic and dyskinetic aneurysms of various sizes on ventricular function. RESULTS: The results indicated that an akinetic aneurysm produces little or no mechanical disadvantage with respect to ventricular pressure since systolic paradox is minimal. However, a dyskinetic aneurysm, irrespective of size, will usually compromise ventricular function due to paradoxical systolic expansion in the bulging aneurysmic sac. In vivo, other factors, such as blood coagulation and rhythm disturbances, may influence these results. CONCLUSIONS: An akinetic aneurysm causes little or no mechanical disadvantage while the dyskinetic aneurysm, irrespective of size. will restrict ventricular function. The experimental simulation system, notwithstanding its limitations, thus provides a unique procedure to quantify akinetic and dyskinetic aneurysms. PMID- 9370412 TI - Evaluation of pentoxifylline in experimental spinal cord ischemia. AB - OBJECTIVE: Despite the advance of anesthesia and surgery, postoperative neurological dysfunction has remained a challenging problem after descending and thoracoabdominal aortic surgery. The pathophysiology of early and especially late paraplegia is not clearly understood. The effect of pentoxifylline (PTX), an agent known to inhibit in vitro neutrophil activation and improve recovery after cerebral ischemia in animals, was investigated on spinal cord protection. METHODS: Twenty four New Zealand white rabbits were used for spinal cord ischemia models. Infrarenal aortic occlusion devices were placed. After 48 h, the rabbits were randomly taken for study. The PTX groups (n = 12) were given PTX 40 mg/kg i.v. bolus followed by 0.2 mg/kg/min infusion. The control (CT) group (n = 12) received normal saline. Two groups underwent temporary (20-24 min) spinal cord ischemia in a conscious state. After the operation, the spinal cord function was assessed at 6, 12, 24, 48 and 72 h by the scale (score of 5 = normal hop, score of 0 = no movement). Histological analysis of the spinal cords was carried out immediately after acute paraplegia or within 24 h after development of delayed paraplegia. RESULTS: During the aortic occlusion, the distal aortic pressures were the same in both groups (PTX group: 14.92 +/- 3.78 mmHg; CT group: 17.42 +/- 3.2 mmHg). At the 72nd h, the scores were not different in the PTX group (1.58 +/ 2.11) and in the CT group (0.83 +/- 1.95) (P = 0.817). Acute paraplegia developed in 3 rabbits (25%) of each group. Delayed paraplegia was observed in 6 rabbits (50%) in the PTX group and 7 rabbits (58%) in the CT group. On morphological examination on the spinal cords, ischemic changes were observed in both groups. Although neutrophil leukocytes were noted in the control group with acute paraplegia and macrophage infiltration was noted in the control group with delayed paraplegia, there was not any leukocyte or macrophage sequestration in the PTX group. CONCLUSIONS: Neurological deficits after spinal cord ischemic/reperfusion injury were not directly responsible for blood-originated phagocytic cells and the inhibition of this type of cell function did not change the outcome. PMID- 9370413 TI - Combined heart and kidney transplantation: an effective therapeutic option- report of six cases. AB - Six cases of combined heart and kidney transplantation with organs from the same donor are reported. All six patients suffered from primary end-stage kidney disease, two chronic glomerulonephritis, two glomerulosclerosis, one chronic pyelonephritis and one with unknown etiology. Four patients were undergoing hemodialysis. Three patients had the diagnosis of ischemic heart disease, one dilated cardiomyopathy secondary to congenital heart disease, two idiopathic dilated cardiomyopathy. Five were males and one female. Ages ranged from 38 to 54 years. On-site or short-distance young donors with normal renal function and good cardiac function necessitating low inotropic support were selected. ABO compatibility was used exclusively. Orthotopic heart transplantation was performed first. During cardiopulmonary bypass, hemofiltration was used in four cases. Kidney transplantation was performed immediately after the closure of the chest. Diuresis was immediate in all cases. No cardiac rejection was documented at EMB. Renal function normalized within few days with no signs of kidney rejection. All six patients are alive and well with normal cardiac and renal function at a mean follow-up of 43 months. Patients and donors selection associated with a proper surgical strategy and prompt immunosuppressive therapy administration make the combined heart and kidney transplantation an effective therapeutic option. PMID- 9370414 TI - VATS resection of an oesophageal leiomyoma in a patient with neurofibromatosis Recklinghausen. AB - A series of reports in the literature suggest an association of neurofibromatosis Recklinghausen with intestinal tumors as carcinoids, leiomyomas and leiomyosarcomas. We present a case of a 23-year-old man with severe cutaneous manifestation of neurofibromatosis. Dysphagia was the main symptom. CT scan suggested the diagnosis of an oesophageal leiomyoma. The oesophageal muscle layers were split and the tumor was enucleated by video assisted thoracoscopic surgery (VATS). The postoperative course was uneventful. The patient was drinking liquids from day 1 and was eating a normal diet from day 3 postoperatively. He was dismissed from the hospital on the 4th postoperative day. We conclude that in patients with neurofibromatosis and oesophageal symptoms an intestinal manifestation of the disease in the oesophagus has to be considered and that VATS resection of intramural and extrinsic oesophageal leiomyomas is the treatment of choice. PMID- 9370415 TI - Anomalous origin of circumflex coronary artery from the right pulmonary artery associated with subaortic stenosis and coarctation of the aorta. AB - Anomalous origin of the circumflex coronary artery is extremely rare and may cause acute cardiac decompensation associated with correction of coexisting congenital malformations. We describe a 10-year-old female patient who underwent surgical repair of the aortic coarctation at 4 years of age. Six years later, she presented with chest pain during exercise. Cardiac catheterization demonstrated 25 mmHg subaortic systolic gradient and retrograde filling of the circumflex coronary artery from the left anterior descending and right coronary artery, with drainage into the right pulmonary artery. Reimplantation of the anomalous circumflex coronary artery to the aorta and resection of subaortic fibrous membrane was performed. Her postoperative course was uneventful, with complete relief of symptoms. PMID- 9370417 TI - Interrupted aortic arch, aorto-pulmonary window and aortic origin of the right pulmonary artery: single stage repair in a neonate. AB - Aorto-pulmonary window, interrupted aortic arch and abnormal origin of the right pulmonary artery from the aorta, combined with patent ductus arteriosus and with intact ventricular septum, is a very rare and complex cardiac malformation. We report one-stage repair in a 4 day-old neonate, using aortic homograft tissue to reconstruct the ascending aorta. PMID- 9370416 TI - Surgical retrieval of undeployed intracoronary stent without cardiopulmonary bypass. AB - Intracoronary stenting has now become a widely established method for treatment of complications of coronary angioplasty. The risk of stent embolism exists and if not retrieved, it may lead to thrombosis and coronary occlusion with myocardial infarction. We report a case of embolism of an undeployed intracoronary stent where there was failure of percutaneous attempts to pull back the stent, requiring surgical retrieval and simultaneous coronary artery bypass grafting, both without cardiopulmonary bypass. PMID- 9370418 TI - Pregnancy with aortic dissection in Ehler-Danlos syndrome. Staged replacement of the total aorta (10-year follow-up). AB - Pregnancy complicated by aortic dissection in patients with hereditary disorder of connective tissue presents interesting considerations including management of caesarean section with the unexpected need for cardiac surgery in emergency. Generalizations can be made on management principles with long-term follow-up requiring an aggressive individualized approach by a multidisciplinary team. A 33 year-old parturient presenting an aortic dissection at 37 weeks gestation required prompt diagnosis of Ehlers-Danlos syndrome in combination with correct surgical therapy resulted in the survival of both the mother and infant. During the 10-year follow-up, multiple complex dissection required transverse aortic arch and thoracoabdominal aortic replacement. PMID- 9370419 TI - Comparison between intercostal and diaphragmatic flap in the surgical treatment of early bronchopleural fistula. PMID- 9370420 TI - Platelet function, plasma expanders, hypocalcaemia-induced artefacts and cardiopulmonary bypass. PMID- 9370421 TI - Stochastic resonance at the molecular level. PMID- 9370422 TI - Protein attraction in membranes induced by lipid fluctuations. AB - The nonspecific lipid-mediated attraction between two proteins embedded in a bilayer membrane have been investigated for a model system using Monte Carlo simulations. We found two types of attraction with different regimes. A depletion induced attraction in the range r < sigmaL, where sigmaL is the diameter of a lipid and r is the distance between the surfaces of the two proteins, and a fluctuation-induced attraction in the range 1 < r/sigmaL < 6, which originates from the gradients of density and orientational fluctuations of the lipids around each protein. The effective potential of the latter type of attraction decays exponentially with U(r) approximately exp(r/vi) where the correlation length is vi/sigmaL approximately 3.2 in the present model system. PMID- 9370423 TI - Probing the outer vestibule of a sodium channel voltage sensor. AB - The second and third basic residues of the S4 segment of domain 4 (D4:R2 and D4:R3) of the human skeletal muscle Na+ channel are known to be translocated from a cytoplasmic to an extracellular position during depolarization. Accessibilities of individual S4 residues were assayed by alteration of inactivation kinetics during modification of cysteine mutants by hydrophilic methanethiosulfonate reagents. The voltage dependences of the reaction rates are identical for extracellular application of cationic methanethiosulfonate-ethyltrimethylammonium (MTSET) and anionic methanethiosulfonate-ethylsulfonate (MTSES), suggesting that D4:R3C is situated outside the membrane electric field at depolarized voltages. The absolute rate of R3C modification is 281-fold greater for MTSET than for MTSES, however, suggesting that at depolarized voltages this S4 thiol resides in a negatively charged hydrophilic crevice. The two hydrophobic residues between D4:R2C and D4:R3C in the primary sequence (L1452 and A1453) are not externally exposed at any voltage. An alpha-helical representation of D4/S4 shows that the basic residues D4:R2 and D4:R3 are on the face opposite that of L1452 and A1453. We propose that in the depolarized conformation, the hydrophobic face of this portion of D4/S4 remains in contact with a hydrophobic region of the extracellular vestibule of the S4 channel. PMID- 9370424 TI - Molecular dynamics simulation of unsaturated lipid bilayers at low hydration: parameterization and comparison with diffraction studies. AB - A potential energy function for unsaturated hydrocarbons is proposed and is shown to agree well with experiment, using molecular dynamics simulations of a water/octene interface and a dioleoyl phosphatidylcholine (DOPC) bilayer. The simulation results verify most of the assumptions used in interpreting the DOPC experiments, but suggest a few that should be reconsidered. Comparisons with recent results of a simulation of a dipalmitoyl phosphatidylcholine (DPPC) lipid bilayer show that disorder is comparable, even though the temperature, hydration level, and surface area/lipid for DOPC are lower. These observations highlight the dramatic effects of unsaturation on bilayer structure. PMID- 9370425 TI - Meta-stability of the hemifusion intermediate induced by glycosylphosphatidylinositol-anchored influenza hemagglutinin. AB - Fusion between influenza virus and target membranes is mediated by the viral glycoprotein hemagglutinin (HA). Replacement of the transmembrane domain of HA with a glycosylphosphatidylinositol (GPI) membrane anchor allows lipid mixing but not the establishment of cytoplasmic continuity. This observation led to the proposal that the fusion mechanism passes through an intermediate stage corresponding to hemifusion between outer monolayers. We have used confocal fluorescence microscopy to study the movement of probes for specific bilayer leaflets of erythrocytes fusing with HA-expressing cells. N-Rh-PE and NBD-PC were used for specific labeling of the outer and inner membrane leaflet, respectively. In the case of GPI-HA-induced fusion, different behaviors of lipid transfer were observed, which include 1) exclusive movement of N-Rh-PE (hemifusion), 2) preferential movement of N-Rh-PE relative to NBD-PC, and 3) equal movement of both lipid analogs. The relative population of these intermediate states was dependent on the time after application of a low pH trigger for fusion. At early time points, hemifusion was more common and full redistribution of both bilayers was rare, whereas later full redistribution of both probes was frequently observed. In contrast to wild-type HA, the latter was not accompanied by mixing of the cytoplasmic marker Lucifer Yellow. We conclude that 1) the GPI-HA-mediated hemifusion intermediate is meta-stable and 2) expansion of an aqueous fusion pore requires the transmembrane and/or cytoplasmic domain of HA. PMID- 9370426 TI - X-ray diffraction studies of cross-bridges weakly bound to actin in relaxed skinned fibers of rabbit psoas muscle. AB - X-ray diffraction patterns were obtained from skinned rabbit psoas muscle under relaxing and rigor conditions over a wide range of ionic strengths (50-170 mM) and temperatures (1 degree C-30 degrees C). For the first time, an intensification of the first actin-based layer line is observed in the relaxed muscle. The intensification, which increases with decreasing ionic strength at various temperatures, including 30 degrees C, parallels the formation of weakly attached cross-bridges in the relaxed muscle. However, the overall intensities of the actin-based layer lines are low. Furthermore, the level of diffuse scattering, presumably a measure of disorder among the cross-bridges, is little affected by changing ionic strength at a given temperature. The results suggest that the intensification of the first actin layer line is most likely due to the cross-bridges weakly bound to actin, and that the orientations of the weakly attached cross-bridges are hardly distinguishable from the detached cross bridges. This suggests that the orientations of the weakly attached cross-bridges are not precisely defined with respect to the actin helix, i.e., nonstereospecific. Intensities of the myosin-based layer lines are only marginally affected by changing ionic strength, but markedly by temperature. The results could be explained if in a relaxed muscle the cross-bridges are distributed between a helically ordered and a disordered population with respect to myosin filament structure. Within the disordered population, some are weakly attached to actin and others are detached. The fraction of cross-bridges in the helically ordered assembly is primarily a function of temperature, while the distribution between the weakly attached and the detached within the disordered population is mainly affected by ionic strength. Some other notable features in the diffraction patterns include a approximately 1% decrease in the pitch of the myosin helix as the temperature is raised from 4 degrees C to 20 degrees C. PMID- 9370427 TI - Temperature-induced structural changes in the myosin thick filament of skinned rabbit psoas muscle. AB - By using synchrotron radiation and an imaging plate for recording diffraction patterns, we have obtained high-resolution x-ray patterns from relaxed rabbit psoas muscle at temperatures ranging from 1 degree C to 30 degrees C. This allowed us to obtain intensity profiles of the first six myosin layer lines and apply a model-building approach for structural analysis. At temperatures 20 degrees C and higher, the layer lines are sharp with clearly defined maxima. Modeling based on the data obtained at 20 degrees C reveals that the average center of the cross-bridges is at 135 A from the center of the thick filament and both of the myosin heads appear to wrap around the backbone. At 10 degrees C and lower, the layer lines become very weak and diffuse scattering increases considerably. At 4 degrees C, the peak of the first layer line shifts toward the meridian from 0.0047 to 0.0038 A(-1) and decreases in intensity approximately by a factor of four compared to that at 20 degrees C, although the intensities of higher-order layer lines remain approximately 10-15% of the first layer line. Our modeling suggests that as the temperature is lowered from 20 degrees C to 4 degrees C the center of cross-bridges extends radially away from the center of the filament (135 A to 175 A). Furthermore, the fraction of helically ordered cross-bridges decreases at least by a factor of two, while the isotropic disorder (the temperature factor) remains approximately unchanged. Our results on the order/disordering effects of temperature are in general agreement with earlier results of Wray [Wray, J. 1987. Structure of relaxed myosin filaments in relation to nucleotide state in vertebrate skeletal muscle. J. Muscle Res. Cell Motil. 8:62a (Abstr.)] and Lowy et al. (Lowy, J., D. Popp, and A. A. Stewart. 1991. X ray studies of order-disorder transitions in the myosin heads of skinned rabbit psoas muscles. Biophys. J. 60:812-824). and support Poulsen and Lowy's hypothesis of coexistence of ordered and disordered cross-bridge populations in muscle (Poulsen, F. R., and J. Lowy. 1983. Small angle scattering from myosin heads in relaxed and rigor frog skeletal muscle. Nature (Lond.). 303:146-152.). However, our results added new insights into the disordered population. Present modeling together with data analysis (Xu, S., S. Malinchik, Th. Kraft, B. Brenner, and L. C. Yu. 1997. X-ray diffraction studies of cross-bridges weakly bound to actin in relaxed skinned fibers of rabbit psoas muscle. Biophys. J. 73:000-000) indicate that in a relaxed muscle, cross-bridges are distributed in three populations: those that are ordered on the thick filament helix and those that are disordered; and within the disordered population, some cross-bridges are detached and some are weakly attached to actin. One critical conclusion of the present study is that the apparent order <--> disorder transition as a function of temperature is not due to an increase/decrease in thermal motion (temperature factor) for the entire population, but a redistribution of cross-bridges among the three populations. Changing the temperature leads to a change in the fraction of cross bridges located on the helix, while changing the ionic strength at a given temperature affects the disordered population leading to a change in the relative fraction of cross-bridges detached from and weakly attached to actin. Since the redistribution is reversible, we suggest that there is an equilibrium among the three populations of cross-bridges. PMID- 9370428 TI - A 5-nanosecond molecular dynamics trajectory for B-DNA: analysis of structure, motions, and solvation. AB - We report the results of four new molecular dynamics (MD) simulations on the DNA duplex of sequence d(CGCGAATTCGCG)2, including explicit consideration of solvent water, and a sufficient number of Na+ counterions to provide electroneutrality to the system. Our simulations are configured particularly to characterize the latest MD models of DNA, and to provide a basis for examining the sensitivity of MD results to the treatment of boundary conditions, electrostatics, initial placement of solvent, and run lengths. The trajectories employ the AMBER 4.1 force field. The simulations use particle mesh Ewald summation for boundary conditions, and range in length from 500 ps to 5.0 ns. Analysis of the results is carried out by means of time series for conformationalm, helicoidal parameters, newly developed indices of DNA axis bending, and groove widths. The results support a dynamically stable model of B-DNA for d(CGCGAATTCGCG)2 over the entire length of the trajectory. The MD results are compared with corresponding crystallographic and NMR studies on the d(CGCGAATTCGCG)2 duplex, and placed in the context of observed behavior of B-DNA by comparisons with the complete crystallographic data base of B-form structures. The calculated distributions of mobile solvent molecules, both water and counterions, are displayed. The calculated solvent structure of the primary solvation shell is compared with the location of ordered solvent positions in the corresponding crystal structure. The results indicate that ordered solvent positions in crystals are roughly twice as structured as bulk water. Detailed analysis of the solvent dynamics reveals evidence of the incorporation of ions in the primary solvation of the minor groove B-form DNA. The idea of localized complexation of otherwise mobile counterions in electronegative pockets in the grooves of DNA helices introduces an additional source of sequence-dependent effects on local conformational, helicoidal, and morphological structure, and may have important implications for understanding the functional energetics and specificity of the interactions of DNA and RNA with regulatory proteins, pharmaceutical agents, and other ligands. PMID- 9370429 TI - Predicting the structure of apolipoprotein A-I in reconstituted high-density lipoprotein disks. AB - In reconstituted high-density lipoproteins, apolipoprotein A-I and phosphatidylcholines combine to form disks in which the amphipathic alpha-helices of apolipoprotein A-1 bind to the edge of a lipid bilayer core, shielding the hydrophic lipid tails from the aqueous environment. We have employed experimental data, sequence analysis, and molecular modeling to construct an atomic model of such a reconstituted high-density lipoprotein disk consisting of two apolipoprotein A-I proteins and 160 palmitoyloleoylphosphatidylcholine lipids. The initial globular domain (1-47) of apolipoprotein A-I was excluded from the model, which was hydrated with an 8-A shell of water molecules. Molecular dynamics and simulated annealing were used to test the stability of the model. Both head-to-tail and head-to-head forms of a reconstituted high-density lipoprotein were simulated. In our simulations the protein contained and adhered to the lipid bilayer while providing good coverage of the lipid tails. PMID- 9370430 TI - Effects of bath resistance on action potentials in the squid giant axon: myocardial implications. AB - This study presents a simplified version of the quasi-one-dimensional theory (Wu, J., E. A. Johnson, and J. M. Kootsey. 1996. A quasi-one-dimensional theory for anisotropic propagation of excitation in cardiac muscle. Biophys. J. 71:2427 2439) with two components of the extracellular current, along and perpendicular to the axis, and a simulation and its experimental confirmation for the giant axon of the squid. By extending the one-dimensional core conductor cable equations, this theory predicts, as confirmed by the experiment, that the shapes of the intracellular and the extracellular action potentials are related to the resistance of the bath. Such a result was previously only expected by the field theories. The correlation between the shapes of the intracellular and the extracellular potentials of the giant axon of the squid resembles that observed during the anisotropic propagation of excitation in cardiac muscle. Therefore, this study not only develops a quasi-one-dimensional theory for a squid axon, but also provides one possible factor contributing to the anisotropic propagation of action potentials in cardiac muscle. PMID- 9370433 TI - How are model protein structures distributed in sequence space? AB - The figure-to-structure maps for all uniquely folding sequences of short hydrophobic polar (HP) model proteins on a square lattice is analyzed to investigate aspects considered relevant to evolution. By ranking structures by their frequencies, few very frequent and many rare structures are found. The distribution can be empirically described by a generalized Zipf's law. All structures are relatively compact, yet the most compact ones are rare. Most sequences falling to the same structure belong to "neutral nets." These graphs in sequence space are connected by point mutations and centered around prototype sequences, which tolerate the largest number (up to 55%) of neutral mutations. Profiles have been derived from these homologous sequences. Frequent structures conserve hydrophobic cores only while rare ones are sensitive to surface mutations as well. Shape space covering, i.e., the ability to transform any structure into most others with few point mutations, is very unlikely. It is concluded that many characteristic features of the sequence-to-structure map of real proteins, such as the dominance of few folds, can be explained by the simple HP model. In analogy to protein families, nets are dense and well separated in sequence space. Potential implications in better understanding the evolution of proteins and applications to improving database searches are discussed. PMID- 9370431 TI - Does conformational free energy distinguish loop conformations in proteins? AB - Limitations in protein homology modeling often arise from the inability to adequately model loops. In this paper we focus on the selection of loop conformations. We present a complete computational treatment that allows the screening of loop conformations to identify those that best fit a molecular model. The stability of a loop in a protein is evaluated via computations of conformational free energies in solution, i.e., the free energy difference between the reference structure and the modeled one. A thermodynamic cycle is used for calculation of the conformational free energy, in which the total free energy of the reference state (i.e., gas phase) is the CHARMm potential energy. The electrostatic contribution of the solvation free energy is obtained from solving the finite-difference Poisson-Boltzmann equation. The nonpolar contribution is based on a surface area-based expression. We applied this computational scheme to a simple but well-characterized system, the antibody hypervariable loop (complementarity-determining region, CDR). Instead of creating loop conformations, we generated a database of loops extracted from high resolution crystal structures of proteins, which display geometrical similarities with antibody CDRs. We inserted loops from our database into a framework of an antibody; then we calculated the conformational free energies of each loop. Results show that we successfully identified loops with a "reference-like" CDR geometry, with the lowest conformational free energy in gas phase only. Surprisingly, the solvation energy term plays a confusing role, sometimes discriminating "reference-like" CDR geometry and many times allowing "non reference-like" conformations to have the lowest conformational free energies (for short loops). Most "reference-like" loop conformations are separated from others by a gap in the gas phase conformational free energy scale. Naturally, loops from antibody molecules are found to be the best models for long CDRs (> or = 6 residues), mainly because of a better packing of backbone atoms into the framework of the antibody model. PMID- 9370432 TI - Molecular dynamics of individual alpha-helices of bacteriorhodopsin in dimyristol phosphatidylocholine. I. Structure and dynamics. AB - Understanding the role of the lipid bilayer in membrane protein structure and dynamics is needed for tertiary structure determination methods. However, the molecular details are not well understood. Molecular dynamics computer calculations can provide insight into these molecular details of protein:lipid interactions. This paper reports on 10 simulations of individual alpha-helices in explicit lipid bilayers. The 10 helices were selected from the bacteriorhodopsin structure as representative alpha-helical membrane folding components. The bilayer is constructed of dimyristoyl phosphatidylcholine molecules. The only major difference between simulations is the primary sequence of the alpha-helix. The results show dramatic differences in motional behavior between alpha-helices. For example, helix A has much smaller root-mean-squared deviations than does helix D. This can be understood in terms of the presence of aromatic residues at the interface for helix A that are not present in helix D. Additional motions are possible for the helices that contain proline side chains relative to other amino acids. The results thus provide insight into the types of motion and the average structures possible for helices within the bilayer setting and demonstrate the strength of molecular simulations in providing molecular details that are not directly visualized in experiments. PMID- 9370434 TI - The dielectric properties of water within model transbilayer pores. AB - Ion channels contain extended columns of water molecules within their transbilayer pores. The dynamic properties of such intrapore water have been shown to differ from those of water in its bulk state. In previous molecular dynamics simulations of two classes of model pore (parallel bundles of Ala20 alpha-helices and antiparallel barrels of Ala10 beta-strands), a substantially reduced translational and rotational mobility of waters was observed within the pore relative to bulk water. Molecular dynamics simulations in the presence of a transpore electrostatic field (i.e., a voltage drop along the pore axis) have been used to estimate the resultant polarization (due to reorientation) of the intrapore water, and hence to determine the local dielectric behavior within the pore. It is shown that the local dielectric constant of water within a pore is reduced for models formed by parallel alpha-helix bundles, but not by those formed by beta-barrels. This result is discussed in the context of electrostatics calculations of ion permeation through channels, and the effect of the local dielectric of water within a helix bundle pore is illustrated with a simple Poisson-Boltzmann calculation. PMID- 9370435 TI - pKa calculations for class A beta-lactamases: methodological and mechanistic implications. AB - Beta-lactamases are responsible for resistance to penicillins and related beta lactam compounds. Despite numerous studies, the identity of the general base involved in the acylation step is still unclear. It has been proposed, on the basis of a previous pKa calculation and analysis of structural data, that the unprotonated Lys73 in the active site could act as the general base. Using a continuum electrostatic model with an improved treatment of the multiple titration site problem, we calculated the pKa values of all titratable residues in the substrate-free TEM-1 and Bacillus licheniformis class A beta-lactamases. The pKa of Lys73 in both enzymes was computed to be above 10, in good agreement with recent experimental data on the TEM-1 beta-lactamase, but inconsistent with the proposal that Lys73 acts as the general base. Even when the closest titratable residue, Glu166, is mutated to a neutral residue, the predicted downward shift of the pKa of Lys73 shows that it is unlikely to act as a proton abstractor in either enzyme. These results support a mechanism in which the proton of the active Ser70 is transferred to the carboxylate group of Glu166. PMID- 9370436 TI - DNA-lipid complexes: stability of honeycomb-like and spaghetti-like structures. AB - A molecular level theory is presented for the thermodynamic stability of two (similar) types of structural complexes formed by (either single strand or supercoiled) DNA and cationic liposomes, both involving a monolayer-coated DNA as the central structural unit. In the "spaghetti" complex the central unit is surrounded by another, oppositely curved, monolayer, thus forming a bilayer mantle. The "honeycomb" complex is a bundle of hexagonally packed DNA-monolayer units. The formation free energy of these complexes, starting from a planar cationic/neutral lipid bilayer and bare DNA, is expressed as a sum of electrostatic, bending, mixing, and (for the honeycomb) chain frustration contributions. The electrostatic free energy is calculated using the Poisson Boltzmann equation. The bending energy of the mixed lipid layers is treated in the quadratic curvature approximation with composition-dependent bending rigidity and spontaneous curvature. Ideal lipid mixing is assumed within each lipid monolayer. We found that the most stable monolayer-coated DNA units are formed when the charged/neutral lipid composition corresponds (nearly) to charge neutralization; the optimal monolayer radius corresponds to close DNA-monolayer contact. These conclusions are also valid for the honeycomb complex, as the chain frustration energy is found to be negligible. Typically, the stabilization energies for these structures are on the order of 1 k(B)T/A of DNA length, reflecting mainly the balance between the electrostatic and bending energies. The spaghetti complexes are less stable due to the additional bending energy of the external monolayer. A thermodynamic analysis is presented for calculating the equilibrium lipid compositions when the complexes coexist with excess bilayer. PMID- 9370437 TI - Enhancement of protein-protein association rate by interaction potential: accuracy of prediction based on local Boltzmann factor. AB - Electrostatic interactions are known experimentally to enhance the rate of protein-protein association by three to four orders of magnitude. However, theoretical efforts to quantitatively account for such rate enhancement have been hampered by the need to consider a large number of relative configurations of two associating proteins sampled during their diffusional encounter. Our recent work indicates that a good estimate of the rate enhancement is given by the average Boltzmann factor in the region of configurational space where association can effectively take place. This estimate is tested on a model system consisting of two spherical proteins, each with a "reactive patch." Three different forms of interaction potential are considered. Comparison with exact results for the association rate constant demonstrates that predictions based on the local Boltzmann factor are accurate to within approximately 50% for realistic sizes of the reactive region and amplitudes of the interaction potential. PMID- 9370439 TI - Signal transduction across alamethicin ion channels in the presence of noise. AB - We have studied voltage-dependent ion channels of alamethicin reconstituted into an artificial planar lipid bilayer membrane from the point of view of electric signal transduction. Signal transduction properties of these channels are highly sensitive to the external electric noise. Specifically, addition of bandwidth restricted "white" noise of 10-20 mV (r.m.s.) to a small sine wave input signal increases the output signal by approximately 20-40 dB conserving, and even slightly increasing, the signal-to-noise ratio at the system output. We have developed a small-signal adiabatic theory of stochastic resonance for a threshold free system of voltage-dependent ion channels. This theory describes our main experimental findings giving good qualitative understanding of the underlying mechanism. It predicts the right value of the output signal-to-noise ratio and provides a reliable estimate for the noise intensity corresponding to its maximum. Our results suggest that the alamethicin channel in a lipid bilayer is a good model system for studies of mechanisms of primary electrical signal processing in biology showing an important feature of signal transduction improvement by a fluctuating environment. PMID- 9370438 TI - The cholesterol dependence of activation and fast desensitization of the nicotinic acetylcholine receptor. AB - When nicotinic acetylcholine receptors are reconstituted into lipid bilayers lacking cholesterol, agonists no longer stimulate cation flux. The kinetics of this process are difficult to study because variations in vesicle morphology cause errors in flux measurements. We developed a new stopped-flow fluorescence assay to study activation independently of vesicle morphology. When receptors were rapidly mixed with agonist plus ethidium, the earliest fluorescence increase reported the fraction of channels that opened and their apparent rate of fast desensitization. These processes were absent when the receptor was reconstituted into dioleoylphosphatidylcholine or into a mixture of that lipid with dioleoylphosphatidic acid (12 mol%), even though a fluorescent agonist reported that resting-state receptors were still present. The agonist-induced channel opening probability increased with bilayer cholesterol, with a midpoint value of 9 +/- 1.7 mol% and a Hill coefficient of 1.9 +/- 0.69, reaching a plateau above 20-30 mol% cholesterol that was equal to the native value. On the other hand, the observed fast desensitization rate was comparable to that for native membranes from the lowest cholesterol concentration examined (5 mol%). Thus the ability to reach the open state after activation varies with the cholesterol concentration in the bilayer, whereas the rate of the open state to fast desensitized state transition is unaffected. The structural basis for this is unknown, but an interesting corollary is that the channels of newly synthesized receptors are not fully primed by cholesterol until they are inserted into the plasma membrane--a novel form of posttranslational processing. PMID- 9370440 TI - Voltage-dependent behavior of a "ball-and-chain" gramicidin channel. AB - The channel-forming properties of two analogs of gramicidin, gramicidin ethylenediamine (gram-EDA), and gramicidin-N,N-dimethylethylenediamine (gram DMEDA) were studied in planar lipid bilayers, using protons as the permeant ion. These peptides have positively charged amino groups tethered to their C-terminal ends via a linker containing a carbamate group. Gram-DMEDA has two extra methyl groups attached to the terminal amino group, making it a bulkier derivative. The carbamate groups undergo thermal cis-trans isomerization on the 10-100-ms time scale. The conductance behavior of gram-EDA is found to be markedly voltage dependent, whereas the behavior of gram-DMEDA is not. In addition, voltage affects the cis-trans ratios of the carbamate groups of gram-EDA, but not those of gram-DMEDA. A model is proposed to account for these observations, in which voltage can promote the binding of the terminal amino group of gram-EDA to the pore in a "ball-and-chain" fashion. The bulkiness of the gram-DMEDA derivative prevents this binding. PMID- 9370441 TI - Interplay between sodium and calcium dynamics in granule cell presynaptic terminals. AB - Fluorescent indicators were used to detect stimulus-evoked changes in presynaptic levels of intracellular sodium (Na(i)) and calcium (Ca(i)) in granule cell parallel fibers in brain slices from rat cerebellum. Ca(i) increased during stimulation, and three exponentials were needed to approximate its return to prestimulus levels. Ca(i) decayed to approximately 10% of peak levels with tau approximately 100 ms, to approximately 1% of peak values with tau approximately 6 s, and then returned to prestimulus levels with tau approximately 1-2 min. After stimulation, Na(i) accumulated in two phases; one rapid, the other continuing for several hundred milliseconds. The return of Na(i) to prestimulus levels was well approximated by a double exponential decay with time constants of 6-17 s and 2-3 min. Manipulations that prevented calcium entry eliminated both the slow component of sodium entry and the rapid component of Na(i) decay. Reductions of extracellular sodium slowed the rapid phase of Ca(i) decay. These Ca(i) and Na(i) transients were well described by a model in which the plasma membrane of presynaptic boutons contained both a sodium/calcium exchanger and a calcium ATPase (Ca-ATPase). According to this model, immediately after stimulation the sodium/calcium exchanger removes calcium from the terminal more rapidly than does the Ca-ATPase. Eventually, the large concomitant sodium influx brings the exchanger into steady-state, leaving only the Ca-ATPase to remove calcium. This perturbs the equilibrium of the sodium/calcium exchanger, which opposes the Ca ATPase, leading to a slow return of Ca(i) and Na(i) to resting levels. PMID- 9370442 TI - Proton conduction in gramicidin A and in its dioxolane-linked dimer in different lipid bilayers. AB - Gramicidin A (gA) molecules were covalently linked with a dioxolane ring. Dioxolane-linked gA dimers formed ion channels, selective for monovalent cations, in planar lipid bilayers. The main goal of this study was to compare the functional single ion channel properties of natural gA and its covalently linked dimer in two different lipid bilayers and HCl concentrations (10-8000 mM). Two ion channels with different gating and conductance properties were identified in bilayers from the product of dimerization reaction. The most commonly observed and most stable gramicidin A dimer is the main object of this study. This gramicidin dimer remained in the open state most of the time, with brief closing flickers (tau(closed) approximately 30 micros). The frequency of closing flickers increased with transmembrane potential, making the mean open time moderately voltage dependent (tau(open) changed approximately 1.43-fold/100 mV). Such gating behavior is markedly different from what is seen in natural gA channels. In PEPC (phosphatidylethanolamine-phosphatidylcholine) bilayers, single-channel current voltage relationships had an ohmic behavior at low voltages, and a marked sublinearity at relatively higher voltages. This behavior contrasts with what was previously described in GMO (glycerylmonooleate) bilayers. In PEPC bilayers, the linear conductance of single-channel proton currents at different proton concentrations was essentially the same for both natural and gA dimers. g(max) and K(D), obtained from fitting experimental points to a Langmuir adsorption isotherm, were approximately 1500 pS and 300 mM, respectively, for both the natural gA and its dimer. In GMO bilayers, however, proton affinities of gA and the dioxolane-dimer were significantly lower (K(D) of approximately 1 and 1.5 M, respectively), and the g(max) higher (approximately 1750 and 2150 pS, respectively) than in PEPC bilayers. Furthermore, the relationship between single channel conductance and proton concentration was linear at low bulk concentrations of H+ (0.01-2 M) and saturated at concentrations of more than 3 M. It is concluded that 1) The mobility of protons in gramicidin A channels in different lipid bilayers is remarkably similar to proton mobilities in aqueous solutions. In particular, at high concentrations of HCl, proton mobilities in gramicidin A channel and in solution differ by only 25%. 2) Differences between proton conductances in gramicidin A channels in GMO and PEPC cannot be explained by surface charge effects on PEPC membranes. It is proposed that protonated phospholipids adjacent to the mouth of the pore act as an additional source of protons for conduction through gA channels in relation to GMO bilayers. 3) Some experimental results cannot be reconciled with simple alterations in access resistance to proton flow in gA channels. Said differences could be explained if the structure and/or dynamics of water molecules inside gramicidin A channels is modulated by the lipid environment and by modifications in the structure of gA channels. 4) The dioxolane ring is probably responsible for the closing flickers seen in the dimer channel. However, other factors can also influence closing flickers. PMID- 9370443 TI - Sodium leak pathway and substrate binding order in the Na+-glucose cotransporter. AB - The Na+-glucose cotransporter (SGLT1) expressed in Xenopus laevis oocytes was shown to generate a phlorizin-sensitive sodium leak in the absence of sugars. Using the current model for SGLT1, where the sodium leak was presumed to occur after two sodium ions are bound to the free carrier before glucose binding, a characteristic concentration constant (Kc) was introduced to describe the relative importance of the sodium leak versus Na+-glucose cotransport currents. Kc represents the glucose concentration at which the Na+-glucose cotransport current is equal to the sodium leak. As both the sodium leak and the Na+-glucose cotransport current are predicted to occur after the binding of two sodium ions, the model predicted that Kc should be sodium-independent. However, by using a two microelectrode voltage-clamp technique, the observed Kc was shown to depend strongly on the external sodium concentration ([Na+]o): it was four times higher at 5 mM [Na+]o than at 20 mM [Na+]o. In addition, the magnitude of the sodium leak varied as a function of [Na+]o in a Michaelian fashion, and the sodium affinity constant for the sodium leak was 2-4 times lower than that for cotransport in the presence of low external glucose concentrations (50 or 100 microM), whereas the current model predicted a sigmoidal sodium dependence of the sodium leak and identical sodium affinities for the sodium leak and the Na+ glucose cotransport. These observations indicate that the sodium leak occurs after one sodium ion is associated with the carrier and agree with predictions from a model with the binding order sodium-glucose-sodium. This conclusion was also supported by experiments performed where protons replaced Na+ as a "driving cation." PMID- 9370444 TI - Transmembrane four-helix bundle of influenza A M2 protein channel: structural implications from helix tilt and orientation. AB - The transmembrane portion of the M2 protein from the Influenza A virus has been studied in hydrated dimyristroylphosphotidylcholine lipid bilayers with solid state NMR. Orientational constraints were obtained from isotopically labeled peptide samples mechanically aligned between thin glass plates. 15N chemical shifts from single site labeled samples constrain the molecular frame with respect to the magnetic field. When these constraints are applied to the peptide, modeled as a uniform alpha-helix, the tilt of the helix with respect to the bilayer normal was determined to be 33 degrees +/- 3 degrees. Furthermore, the orientation about the helix axis was also determined within an error of +/- 30 degrees. These results imply that the packing of this tetrameric protein is in a left-handed four-helix bundle. Only with such a large tilt angle are the hydrophilic residues aligned to the channel axis. PMID- 9370445 TI - Activation and deactivation rates of recombinant GABA(A) receptor channels are dependent on alpha-subunit isoform. AB - The role of subunit composition in determining intrinsic maximum activation and deactivation kinetics of GABA(A) receptor channels is unknown. We used rapid ligand application (100-micros solution exchange) to examine the effects of alpha subunit composition on GABA-evoked activation and deactivation rates. HEK 293 cells were transfected with human cDNAs encoding alpha1beta1gamma2- or alpha2beta1gamma2-subunits. Channel kinetics were similar across different transfections of the same subunits and reproducible across several GABA applications in the same patch. Current rise to peak was at least twice as fast for alpha2beta1gamma2 receptors than for alpha1beta1gamma2 receptors (reflected in 10-90% rise times of 0.5 versus 1.0 ms, respectively), and deactivation was six to seven times slower (long time constants of 208 ms versus 31 ms) after saturating GABA applications. Thus alpha-subunit composition determined activation and deactivation kinetics of GABA(A) receptor channels and is therefore likely to influence the kinetics and efficacy of inhibitory postsynaptic currents. PMID- 9370446 TI - Penetration of the insect defensin A into phospholipid monolayers and formation of defensin A-lipid complexes. AB - Defensin A is an inducible cationic protein secreted in the hemolymph of fleshfly Phormia terranovae larvae in response to bacterial or septic injuries. Defensin A is known to permeabilize the bacteria cell membranes by forming voltage-dependent channels. The penetration of this small protein into lipid monolayers was studied as a function of the polar head and acyl chain length of phospholipids. The extent of penetration by defensin A is higher in monolayers made of anionic phospholipids than in monolayers made of zwitterionic phospholipids (phosphatidylcholines), because of electrostatic interactions. From the analysis of the compression isotherm parameters of mixed defensin A/phospholipid monolayers, it appears that defensin A interacts with phospholipid by forming 1:4 complexes. These complexes are not miscible in the lipid phase and induce microheterogeneity in the lipid membrane. These clusters might be related to the ion-channel structures responsible for the biological activity of defensin A. PMID- 9370447 TI - Structural and fusogenic properties of cationic liposomes in the presence of plasmid DNA. AB - The structural and fusogenic properties of large unilamellar vesicles (LUVs) composed of the cationic lipid N-[2,3-(dioleyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA) and 1,2-dioleoyl-3-phosphatidylethanotamine (DOPE) have been examined in the presence of pCMV5 plasmid and correlated with transfection potency. It is shown, employing lipid mixing fusion assays, that pCMV5 plasmid strongly promotes fusion between DOTMA/DOPE (1:1) LUVs and DOTMA/1,2-dioleoyl-3 phosphatidylcholine (DOTMA/DOPC) (1:1) LUVs such that at a cationic lipid-to-DNA charge ratio of 3.0, approximately 80% fusion is observed. The anions citrate and chloride can also trigger fusion, but at much higher concentrations. Freeze fracture electron microscopy studies demonstrate the tendency of cationic vesicles to form clusters at low pCMV5 content, whereas macroscopic fused aggregates can be observed at higher plasmid levels. 31P NMR studies of the fused DNA-DOTMA/DOPE (1:1) complexes obtained at high plasmid levels (charge ratio 1.0) reveal narrow "isotropic" 31P NMR resonances, whereas the corresponding DOPC containing systems exhibit much broader "bilayer" 31P NMR spectra. In agreement with previous studies, the transfection potency of the DOPE-containing systems is dramatically higher than for the DOPC-containing complexes, indicating a correlation between transfection potential and the motional properties of endogenous lipids. Interestingly, it was found that the complexes could be separated by centrifugation into a pellet fraction, which exhibits superior transfection potencies, and a supernatant fraction. Again, the pellet fraction in the DOPE-containing system exhibits a significantly narrower 31P NMR resonance than the corresponding DOPC-containing system. It is suggested that the 31P NMR characteristics of complexes exhibiting higher transfection potencies are consistent with the presence of nonbilayer lipid structures, which may play a direct role in the fusion or membrane destabilization events vital to transfection. PMID- 9370448 TI - Spin-label electron spin resonance studies on the interactions of lysine peptides with phospholipid membranes. AB - The interactions of lysine oligopeptides with dimyristoyl phosphatidylglycerol (DMPG) bilayer membranes were studied using spin-labeled lipids and electron spin resonance spectroscopy. Tetralysine and pentalysine were chosen as models for the basic amino acid clusters found in a variety of cytoplasmic membrane-associating proteins, and polylysine was chosen as representative of highly basic peripherally bound proteins. A greater motional restriction of the lipid chains was found with increasing length of the peptide, while the saturation ratio of lipids per peptide was lower for the shorter peptides. In DMPG and dimyristoylphosphatidylserine host membranes, the perturbation of the lipid chain mobility by polylysine was greater for negatively charged spin-labeled lipids than for zwitterionic lipids, but for the shorter lysine peptides these differences were smaller. In mixed bilayers composed of DMPG and dimyristoylphosphatidylcholine, little difference was found in selectivity between spin-labeled phospholipid species on binding pentalysine. Surface binding of the basic lysine peptides strongly reduced the interfacial pK of spin-labeled fatty acid incorporated into the DMPG bilayers, to a greater extent for polylysine than for tetralysine or pentalysine at saturation. The results are consistent with a predominantly electrostatic interaction with the shorter lysine peptides, but with a closer surface association with the longer polylysine peptide. PMID- 9370449 TI - Differential scanning calorimetry of chain-melting phase transitions of N acylphosphatidylethanolamines. AB - Phosphatidylethanolamines in which the polar headgroup is N-acylated by a long chain fatty acid (N-acyl PEs) are present in many plasma membranes under normal conditions, and their content increases dramatically in response to membrane stress in a variety of organisms. The thermotropic phase behavior of a homologous series of saturated N-acyl PEs, in which the length of the N-acyl chain is equal to that of the O-acyl chains attached at the glycerol backbone, has been investigated by differential scanning calorimetry (DSC). All fully hydrated N acyl PEs with even chain lengths from C-12 to C-18 exhibit sharp endothermic chain-melting phase transitions in the absence of salt and in 1 M NaCl. Cooperative chain-melting is demonstrated directly by the temperature dependence of the electron spin resonance spectra from probe phospholipids bearing a spin label group in the acyl chain. The calorimetric transition enthalpy and the transition entropy obtained from DSC depend approximately linearly on the chain length with incremental values per CH2 group that exceed those of normal diacyl phosphatidylethanolamines, but to an extent that underrepresents the additional N acyl chain. A thermodynamic model is constructed for the chain-length dependences and end effects of the calorimetric quantities, which includes a deficit proportional to the difference in O-acyl and N-acyl chain lengths for nonmatched chains, as is found and justified structurally for mixed-chain diacyl phospholipids. From data on the chain-length dependence of N-acyl diC16PEs, it is then deduced that the N-acyl chains are less well packed than the O-acyl chains and, from the data on the matched-chain N-acyl PEs, that the O-acyl chain packing is similar to that in normal diacyl PEs. The gel-to-fluid phase transition temperatures of the N-acyl PEs in the absence of salt are practically the same as those of the normal diacyl PEs of the corresponding chain lengths, although the transition enthalpies and entropies are appreciably greater, indicating entropy enthalpy compensation. In 1 M NaCl, the transition temperatures are 3-4.5 degrees higher than in the absence of salt, representing the contribution of the electrostatic surface potential of the N-acyl PEs. PMID- 9370450 TI - Interaction of octyl-beta-thioglucopyranoside with lipid membranes. AB - Octyl-beta-thioglucopyranoside (octyl thioglucoside, OTG) is a nonionic surfactant used for the purification, reconstitution, and crystallization of membrane proteins. The thermodynamic properties of the OTG-membrane partition equilibrium are not known and have been investigated here with high-sensitivity titration calorimetry. The critical concentration for inducing the bilayer <==> micelle transition was determined as cD* = 7.3 mM by 90 degree light scattering. All thermodynamic studies were performed well below this limit. Sonified, unilamellar lipid vesicles composed of 1-palmitoyl-2-oleoyl-sn-glycero-3 phosphocholine (POPC) with and without cholesterol were employed in the titration calorimetry experiments, and the temperature was varied between 28 degrees C and 45 degrees C. Depending on the surfactant concentration in the membrane, the partition enthalpy was found to be exothermic or endothermic, leading to unusual titration patterns. A quantitative interpretation of all titration curves was possible with the following model: 1) The partitioning of OTG into the membrane follows a simple partition law, i.e., Xb = Kc(D,f), where Xb denotes the molar amount of detergent bound per mole of lipid and c(D,f) is the detergent concentration in bulk solution. 2) The partition enthalpy for the transfer of OTG from the aqueous phase to the membrane depends linearly on the mole fraction, R, of detergent in the membrane. All calorimetric OTG titration curves can be characterized quantitatively by using a composition-dependent partition enthalpy of the form deltaHD(R) = -0.08 + 1.7 R (kcal/mol) (at 28 degrees C). At low OTG concentrations (R < or = 0.05) the reaction enthalpy is exothermic; it becomes distinctly endothermic as more and more surfactant is incorporated into the membrane. OTG has a partition constant of 240 M(-1) and is more hydrophobic than its oxygen-containing analog, octyl-beta-D-glucopyranoside (OG). Including a third nonionic amphiphile, octa(ethyleneoxide) dodecylether (C12EO8), an empirical relation can be established between the Gibbs energies of membrane partitioning, deltaGp, and micelle formation, deltaGmic, with deltaGp = 1.398 + 0.647 deltaGmic (kcal/mol). The partition constant of OTG is practically independent of temperature and of the cholesterol content of the membrane. In contrast, the partition enthalpy shows a strong temperature dependence. The molar specific heat capacity of the transfer of OTG from the aqueous phase to the membrane is deltaCp = -98 cal/(mol x K). The OTG partition enthalpy is also dependent on the cholesterol content of the membrane. It increases by approximately 1 kcal/mol at 50 mol% cholesterol. As the partition constant remains unchanged, the increase in enthalpy is compensated for by a corresponding increase in entropy, presumably caused by a restructuring of the membrane hydration layer. PMID- 9370451 TI - Water translational motion at the bilayer interface: an NMR relaxation dispersion measurement. AB - Nuclear magnetic relaxation rates for water protons in aqueous palmitoyloleoylphosphatidylcholine vesicle suspensions containing different nitroxide free radical spin labels are reported as a function of magnetic field strength corresponding to proton Larmor frequencies from 10 kHz to 30 MHz. Under these conditions the water proton relaxation rate is determined by the magnetic coupling between the water protons and the paramagnetic nitroxide fixed on the phospholipid. This coupling is made time-dependent by the relative translational motion of the water proton spins past the nitroxide radical. Using theories developed by Freed and others, we interpret the NMR relaxation data in terms of localized water translational motion and find that the translational diffusion constant for water within approximately 10 A of the phospholipid surface is 6 x 10(-10) m2 s(-1) at 298 K. Similar results are obtained for three different nitroxide labels positioned at different points on the lipid. The diffusion is a thermally activated process with an activation energy only slightly higher than that for bulk water. PMID- 9370452 TI - Effects of size of macrocyclic polyamides on their rate of diffusion in model membranes. AB - A series of homologous amphiphilic molecules with surface areas in the range of 0.3 nm2 to 3.0 nm2 were prepared and used to investigate the diffusion in model dimyristoylphosphatidylcholine membranes as a function of temperature. The diffusion behavior of smaller molecules can be described by the interfacial viscosity limited free area theory promoted by Vaz and his co-workers, and that of the larger molecules can best be modeled by a recent interpretation of the theoretical description proposed by Evans and Sackmann. The experimental data show that the rate of diffusion is controlled by the size of the molecules at the interface of the lipid membrane, and provide evidence for a view of the membrane as a hydrodynamic triple layer with a low-viscosity central layer encased by two more viscous, yet fluid, layers. PMID- 9370453 TI - A single-residue deletion alters the lipid selectivity of a K+ channel-associated peptide in the beta-conformation: spin label electron spin resonance studies. AB - Lipid-peptide interactions with the 27-residue peptide of sequence KLEALYILMVLGFFGFFTLGIMLSYIR reconstituted as beta-sheet assemblies in dimyristoylphosphatidylcholine bilayers have been studied by electron spin resonance (ESR) spectroscopy with spin-labeled lipids. The peptide corresponds to residues 42-68 of the IsK voltage-gated K+ channel protein and contains the single putative transmembrane span of this protein. Lipid-peptide interactions give rise to a second component in the ESR spectra of lipids spin-labeled on the 14C atom of the chain that corresponds to restriction of the lipid mobility by direct interaction with the peptide assemblies. From the dependence on the lipid/peptide ratio, the stoichiometry of lipid interaction is found to be about two phospholipids/peptide monomer. The sequence of selectivity for lipid association with the peptide assemblies is in the order phosphatidic acid > stearic acid = phosphatidylserine > phosphatidylglycerol = phosphatidylcholine. Comparison with previous data for a corresponding 26-residue mutant peptide with a single deletion of the apolar residue Leu2 (Horvath et al., 1995. Biochemistry 34:3893-3898), indicates a very similar mode of membrane incorporation for native and mutant peptides, but a strongly modified pattern and degree of specificity for the interaction with negatively charged lipids. The latter is interpreted in terms of the relative orientations of the charged amino acid side chains in the beta-sheet assemblies of the native and deletion-mutant peptides. PMID- 9370454 TI - Effect of calcium on phospholipid interaction with pulmonary surfactant protein C. AB - Porcine pulmonary surfactant-associated protein SP-C was incorporated into bilayers of chain-perdeuterated dipalmitoylphosphatidylglycerol (DPPG-d62) and chain-perdeuterated dipalmitoyl-phosphatidylcholine (DPPC-d62) and into bilayers containing 70 mol% dipalmitoyl-phosphatidylcholine (DPPC) and 30 mol% DPPG-d62 or 70 mol% DPPC-d62 and 30 mol% dipalmitoylphosphatidylglycerol (DPPG). The effect of SP-C on the phase behavior, lipid chain order, and dynamics in these bilayers was examined by using deuterium nuclear magnetic resonance. SP-C was found to have a similar effect on the chain order and phase behavior of DPPC-d62 and DPPG d62 in bilayers with a single lipid component. In gel phase DPPC/DPPG (7:3) bilayers with one or the other lipid component chain-perdeuterated, SP-C was found to affect first spectral moment more strongly for DPPG-d62 than for DPPC d62. This may indicate that SP-C induced a nonrandom lateral distribution in the mixed lipid bilayer. SP-C was also found to influence motions responsible for deuteron transverse relaxation in both the gel and liquid crystalline phases. The presence of 5 mM Ca2+ in the aqueous phase substantially altered the effect of SP C on transverse relaxation in the bilayer. PMID- 9370456 TI - Exchange of monooleoylphosphatidylcholine as monomer and micelle with membranes containing poly(ethylene glycol)-lipid. AB - Surface-grafted polymers, such as poly(ethylene glycol) (PEG), provide an effective steric barrier against surface-surface and surface-macromolecule interactions. In the present work, we have studied the exchange of monooleoylphosphatidylcholine (MOPC) with vesicle membranes containing 750 mol wt surface-grafted PEG (incorporated as PEG-lipid) from 0 to 20 mol % and have analyzed the experimental results in terms of thermodynamic and stationary equilibrium models. Micropipette manipulation was used to expose a single lipid vesicle to a flow of MOPC solution (0.025 microM to 500 microM). MOPC uptake was measured by a direct measure of the vesicle area change. The presence of PEG(750) lipid in the vesicle membrane inhibited the partitioning of MOPC micelles (and to some extent microaggregates) into the membrane, while even up to 20 mol % PEG lipid, it did not affect the exchange of MOPC monomers both into and out of the membrane. The experimental data and theoretical models show that grafted PEG acts as a very effective molecular scale "filter" and prevents micelle-membrane contact, substantially decreasing the apparent rate and amount of MOPC taken up by the membrane, thereby stabilizing the membrane in a solution of MOPC that would otherwise dissolve it. PMID- 9370455 TI - Effects of dipalmitoylglycerol and fatty acids on membrane structure and protein kinase C activity. AB - The individual and combined effects of the saturated diacylglycerol (DAG) dipalmitin (DP) and saturated or polyunsaturated unesterified fatty acids (PUFAs) on both the structure of phosphatidylcholine/phosphatidylserine (PC/PS; 4:1 mol/mol) bilayers and on protein kinase C (PKC) activity were studied using 2H nuclear magnetic resonance (NMR) and enzyme activity assays. In the absence of DP, PUFAs only slightly activated PKC whereas palmitic acid had no effect. In the absence of fatty acids, DP induced lateral phase separation of the bilayer into liquid-crystalline and gel phases. Under these conditions virtually all DP was sequestered into the gel phase and no activation of PKC was observed. The addition of polyunsaturated arachidonic or docosahexaenoic acids to the DP containing bilayers significantly increased the relative amounts of DP and other lipid components in the liquid-crystalline phase, correlating with a dramatic increase in PKC activity. Furthermore, the effect was greater with PS, resulting in an enrichment of PS in the liquid-crystalline domains. In the presence of DP, palmitic acid did not decrease the amount of gel phase lipid and had no effect on PKC activity. The results explain the observed lack of PKC-activating capacity of long-chain saturated DAGs as due to the sequestration of DAG into gel domains wherein it is complexed with phospholipids and thus not available for the required interaction with the enzyme. PMID- 9370457 TI - Direct observation in the millisecond time range of fluorescent molecule asymmetrical interaction with the electropermeabilized cell membrane. AB - Interaction of two stains (propidium iodide and ethidium bromide) with electropermeabilized living Chinese hamster ovary cells is observed using an ultrafast fluorescence image acquisition system. The computing process is linked to an ultra-low-light intensifying camera working with a very short time resolution (3.33 ms per image). Altered parts of the cell membrane were identified via the enhancement in fluorescence intensity of the dyes. They reflect the electropermeabilized part of the membrane in which free flow of dye occurred. Images of the fluorescence interaction patterns of the two dyes, in a maximum 20-ms time lag after pulsation, reveal asymmetrical permeabilization of the cell membrane. For electric field intensities higher than a first threshold value, permeabilization is always observed on the anode-facing side of the cell. For electric field intensities over a second higher threshold value, the two electrode-facing hemispheres of the cell are permeabilized, the hemisphere facing the anode being most permeable. These data support the conclusion that electropermeabilization of living cell membrane is affected by its resting potential. The asymmetrical pattern of the dye interaction is not dependent on the nature or concentration of the dye, the ionic strength of the pulsing buffer, or the duration of the pulse. The field intensity determines the fraction of the membrane in which molecular alterations can occur. The extent of alteration in this localized region is determined by the duration of the pulse when a single pulse in the millisecond time range is applied. PMID- 9370459 TI - Deformability and stability of erythrocytes in high-frequency electric fields down to subzero temperatures. AB - High-frequency electric fields can be used to induce deformation of red blood cells. In the temperature domain T = 0 degrees to -15 degrees C (supercooled suspension) and for 25 degrees C this paper examines for human erythrocytes (discocytes, young cell population suspended in a low ionic strength solution with conductivity sigma(25 degrees) = 154 microS/cm) in a sinusoidal electric field (nu = 1 MHz, E0 = 0-18 kV/cm) the following properties and effects as a function of field strength and temperature: 1) viscoelastic response, 2) (shear) deformation (steady-state value obtained from the viscoelastic response time), 3) stability (by experimentally observed breakdown of cell polarization and hemolysis), 4) electrical membrane breakdown and field-induced hemolysis (theoretical calculations for ellipsoidal particles), and 5) mechanical hemolysis. The items 2-4 were also examined for the frequency nu = 100 kHz and for a nonionic solution of very low conductivity (sigma(25 degrees) = 10 microS/cm) to support our interpretations of the results for 1 MHz. Below 0 degrees C with decreasing temperature the viscoelastic response time tau(res)(T) for the cells to reach steady-state deformation values d(infinity,E) increases and the deformation d(infinity,E)(T) decreases strongly. Both effects are especially high for low field strengths. The longest response time of approximately 30 s was obtained for -15 degrees C and small deformations. For 1 MHz the cells can be highly elongated up to 2.3 times their initial diameter a0 for 25 degrees and 0 degrees C, 2.1a0 for -10 degrees C and still 1.95a0 for -15 degrees C. For T > or = 0 degrees C the deformation is limited by hemolysis of the cells, which sets in for E0(lysis)(25 degrees) approximately 8 kV/cm and E0(lysis)(0 degrees) approximately 14 kV/cm. These values are approximately three times higher than the corresponding calculated critical field strengths for electrically induced pore formation. Nevertheless, the observed depolarization and hemolysis of the cells is provoked by electrical membrane breakdown rather than by mechanical forces due to the high deformation. For the nonionic solution, where no electrical breakdown is expected in the whole range for E0, the cells can indeed be deformed to even higher values with a low hemolytic rate. Below 0 degrees C we observe no hemolysis at all, not even for the frequency 100 kHz, where the cells hemolyze at 25 degrees C for the much lower field strength E0(lysis) approximately 2.5 kV/cm. Obviously, pore formation and growth are weak for subzero temperatures. PMID- 9370458 TI - Roles of factor Va heavy and light chains in protein and lipid rearrangements associated with the formation of a bovine factor Va-membrane complex. AB - Factor Va is an essential protein cofactor of the enzyme factor Xa, which activates prothrombin to thrombin during blood coagulation. Peptides with an apparent Mr of approximately 94,000 (heavy chain; HC) and approximately 74,000 or 72,000 (light chain; LC) interact in the presence of Ca2+ to form active Va. The two forms of Va-LC differ in their carboxyl-terminal C2 domain. Using Va reconstituted with either LC form, we examined the effects of the two LC species on membrane binding and on the activity of membrane-bound Va. We found that 1) Va composed of the 72,000 LC bound only slightly more tightly to membranes composed of a mixture of neutral and acidic lipids, the Kd being reduced by a factor of approximately 3 at 5 mM and by a factor of 6 at 2 mM Ca2+. 2) The two forms of Va seemed to undergo different conformational changes when bound to a membrane. 3) The activity of bovine Va varied somewhat with LC species, the difference being greatest at limiting Xa concentration. We have also addressed the role of the two Va peptides in membrane lipid rearrangements and binding: 1) Va binding increased lateral packing density in mixed neutral/acidic lipid membranes. In the solid phase, Va-HC had no effect, whereas Va-LC and whole Va had similar but small effects. In the fluid phase, Va-HC and whole Va both altered membrane packing, with Va-HC having the largest effect. 2) Va-HC bound reversibly and in a Ca2+ independent fashion to membranes composed of neutral phospholipid (Kd, approximately 0.3 microM; stoichiometry approximately 91). High ionic strength had little effect on binding. 3) The substantial effect of Va on packing within neutral phospholipid membranes was mimicked by Va-HC. 4) Based on measurements of membrane phase behavior, binding of Va or its peptide components did not induce thermodynamically discernible lateral membrane domains. These results suggest that the membrane association of factor Va is a complex process involving both chains of Va, changes in lipid packing, and changes in protein structure. PMID- 9370460 TI - Mobility of creatine phosphokinase and beta-enolase in cultured muscle cells. AB - The diffusion of beta-enolase and creatine phosphokinase in muscle cells has been studied by modulated fringe pattern photobleaching. Beta-enolase is mobile in the sarcoplasm. At 20 degrees C, the diffusion coefficient is 13.5 +/- 2.5 microm2 s( 1) in the cytosol and 56 microm2 s(-1) in aqueous media. As in the case of dextrans of the same hydrodynamic radius, its mobility is hindered by both the crowding of the fluid phase of the cytoplasm and the screening effect due to myofilaments. A fraction of creatine phosphokinase is mobile in the sarcoplasm. Its diffusion coefficient in the cytosol, 4.5 +/- 1 microm2 s(-1), is lower than that of the dextran of equivalent size. The other fraction (20 to 50%) is very slightly mobile, with an apparent diffusion coefficient varying from 0.0035 to 0.043 microm2 s(-1). This low mobility might be attributed to exchange between free and bound creatine phosphokinase. The bound fraction of the endogenous enzyme was localized by immunocytofluorescence on the cultured muscle cells. Our results favor a localization of bound cytosolic creatine phosphokinase on the M line and a diffuse distribution in all myotubes. PMID- 9370461 TI - Salt effects on the structure and internal dynamics of superhelical DNAs studied by light scattering and Brownian dynamics. AB - Using laser light scattering, we have measured the static and dynamic structure factor of two different superhelical DNAs, p1868 (1868 bp) and simian virus 40 (SV40) (5243 bp), in dilute aqueous solution at salt concentrations between 1 mM and 3 M NaCl. For both DNA molecules, Brownian dynamics (BD) simulations were also performed, using a previously described model. A Fourier mode decomposition procedure was used to compute theoretical light scattering autocorrelation functions (ACFs) from the BD trajectories. Both measured and computed autocorrelation functions were then subjected to the same multiexponential decomposition procedure. Simulated and measured relaxation times as a function of scattering angle were in very good agreement. Similarly, computed and measured static structure factors and radii of gyration agreed within experimental error. One main result of this study is that the amplitudes of the fast-relaxing component in the ACF show a peak at 1 M salt concentration. This nonmonotonic behavior might be caused by an initial increase in the amplitudes of internal motions due to diminishing long-range electrostatic repulsions, followed by a decrease at higher salt concentration due to a compaction of the structure. PMID- 9370463 TI - Observation of an A-DNA to B-DNA transition in a nonhelical nucleic acid hairpin molecule using molecular dynamics. AB - One of the truly challenging problems for molecular dynamics (MD) simulations is demonstrating that the trajectories can sample not only in the vicinity of an experimentally determined structure, but also that the trajectories can find the correct experimental structure starting from some other structure. Frequently these transitions to the correct structure require that the simulations overcome energetic barriers to conformational change. Here we present unrestrained molecular dynamics simulations of the DNA analogs of the RNA 5'-GGACUUCGGUCC-3' hairpin tetraloop. In one simulation we have used deoxyuracil residues, and in the other we have used the native DNA deoxythymine residues. We demonstrate that, on a nanosecond time scale, MD is able to simulate the transitions of both of the A-DNA stems to B-DNA stems within the constraints imposed by the four-base loop that caps the helix. These results suggest that we are now in a position to use MD to address the nature of sequence-dependent structural effects in nonduplex DNA structures. PMID- 9370462 TI - On the origin of the temperature dependence of the supercoiling free energy. AB - Monte Carlo simulations using temperature-invariant torsional and bending rigidities fail to predict the rather steep decline of the experimental supercoiling free energy with increasing temperature, and consequently fail to predict the correct sign and magnitude of the supercoiling entropy. To illustrate this problem, values of the twist energy parameter (E(T)), which governs the supercoiling free energy, were simulated using temperature-invariant torsion and bending potentials and compared to experimental data on pBR322 over a range of temperatures. The slope, -dE(T)/dT, of the simulated values is also compared to the slope derived from previous calorimetric data. The possibility that the discrepancies arise from some hitherto undetected temperature dependence of the torsional rigidity was investigated. The torsion elastic constant of an 1876-bp restriction fragment of pBR322 was measured by time-resolved fluorescence polarization anisotropy of intercalated ethidium over the range 278-323 K, and found to decline substantially over that interval. Simulations of a 4349-bp model DNA were performed using these measured temperature-dependent torsional rigidities. The slope, -dE(T)/dT, of the simulated data agrees satisfactorily with the slope derived from previous calorimetric measurements, but still lies substantially below that of Duguet's data. Models that involve an equilibrium between different secondary structure states with different intrinsic twists and torsion constants provide the most likely explanation for the variation of the torsion constant with T and other pertinent observations. PMID- 9370464 TI - Guanidinium restores the chromophore but not rapid proton release in bacteriorhodopsin mutant R82Q. AB - Replacement of the Arg residue at position 82 in bacteriorhodopsin by Gln or Ala was previously shown to slow the rate of proton release and raise the pK of Asp 85, indicating that R82 is involved both in the proton release reaction and in stabilizing the purple form of the chromophore. We now find that guanidinium chloride lowers the pK of D85, as monitored by the shift of the 587-nm absorbance maximum to 570 nm (blue to purple transition) and increased yield of photointermediate M. The absorbance shift follows a simple binding curve, with an apparent dissociation constant of 20 mM. When membrane surface charge is taken into account, an intrinsic dissociation constant of 0.3 M fits the data over a range of 0.2-1.0 M cation concentration (Na+ plus guanidinium) and pH 5.4-6.7. A chloride counterion is not involved in the observed spectral changes, as chloride up to 0.2 M has little effect on the R82Q chromophore at pH 6, whereas guanidinium sulfate has a similar effect to guanidinium chloride. Furthermore, guanidinium does not affect the chromophore of the double mutant R82Q/D85N. Taken together, these observations suggest that guanidinium binds to a specific site near D85 and restores the purple chromophore. Surprisingly, guanidinium does not restore rapid proton release in the photocycle of R82Q. This result suggests either that guanidinium dissociates during the pump cycle or that it binds with a different hydrogen-bonding geometry than the Arg side chain of the wild type. PMID- 9370465 TI - The role of water in the extracellular half channel of bacteriorhodopsin. AB - The changes in the photocycle of the wild type and several mutant bacteriorhodopsin (D96N, E204Q, and D212N) were studied on dried samples, at relative humidities of 100% and 50%. Samples were prepared from suspensions at pH approximately 5 and at pH approximately 9. Intermediate M with unprotonated Schiff base was observed at the lower humidity, even in the case where the photocycle in suspension did not contain this intermediate (mutant D212N, high pH). The photocycle of the dried sample stopped at intermediate M1 in the extracellular conformation; conformation change, switching the accessibility of the Schiff base to the cytoplasmic side, and proton transport did not occur. The photocycle decayed slowly by dissipating the absorbed energy of the photon, and the protein returned to its initial bacteriorhodopsin state, through several M1 like substates. These substates presumably reflect different paths of the proton back to the Schiff base, as a consequence of the bacteriorhodopsin adopting different conformations by stiffening on dehydration. All intermediates requiring conformational change were hindered in the dried form. The concentration of intermediate L, which appears after isomerization of the retinal from all-trans to 13-cis, during local relaxation of the protein, was unusually low in dried samples. The lack of intermediates N and O demonstrated that the M state did not undergo a change from the extracellular to the cytoplasmic conformation (M1 to M2 transition), as already indicated by Fourier transform infrared spectroscopy, quasielastic incoherent neutron scattering, and electric signal measurements described in the literature. PMID- 9370466 TI - Water-coupled low-frequency modes of myoglobin and lysozyme observed by inelastic neutron scattering. AB - Conformational changes of proteins often involve the relative motion of rigid structural domains. Normal mode analysis and molecular dynamics simulations of small globular proteins predict delocalized vibrations with frequencies below 20 cm(-1), which may be overdamped in solution due to solvent friction. In search of these modes, we have studied deuterium-exchanged myoglobin and lysozyme using inelastic neutron scattering in the low-frequency range at full and low hydration to modify the degree of damping. At room temperature, the hydrated samples exhibit a more pronounced quasielastic spectrum due to diffusive motions than the dehydrated samples. The analysis of the corresponding lineshapes suggests that water modifies mainly the amplitude, but not the characteristic time of fast protein motions. At low temperatures, in contrast, the dehydrated samples exhibit larger motional amplitudes than the hydrated ones. The excess scattering, culminating at 16 cm(-1), is suggested to reflect water-coupled librations of polar side chains that are depressed in the hydrated system by strong intermolecular hydrogen bonding. Both myoglobin and lysozyme exhibit ultra-low frequency modes below 10 cm(-1) in the dry state, possibly related to the breathing modes predicted by harmonic analysis. PMID- 9370467 TI - Protein contributions to redox potentials of homologous rubredoxins: an energy minimization study. AB - The energetic contributions of the protein to the redox potential in an iron sulfur protein are studied via energy minimization, comparing homologous rubredoxins from Clostridium pasteurianum, Desulfovibrio gigas, Desulfovibrio vulgaris, and Pyrococcus furiosus. The reduction reaction was divided into 1) the change in the redox site charge without allowing the protein to respond and 2) the relaxation of the protein in response to the new charge state, focusing on the latter. The energy minimizations predict structural relaxation near the redox site that agrees well with that in crystal structures of oxidized and reduced P. furiosus rubredoxin, but underpredicts it far from the redox site. However, the relaxation energies from the energy-minimized structures agree well with those from the crystal structures, because the polar groups near the redox site are the main determinants and the charged groups are all located at the surface and thus are screened dielectrically. Relaxation energies are necessary for good agreement with experimentally observed differences in reduction energies between C. pasteurianum and the other three rubredoxins. Overall, the relaxation energy is large (over 500 mV) from both the energy-minimized and the crystal structures. In addition, the range in the relaxation energy for the different rubredoxins is large (300 mV), because even though the structural perturbations of the polar groups are small, they are very near the redox site. Thus the relaxation energy is an important factor to consider in reduction energetics. PMID- 9370469 TI - Pressure effects on the proximal heme pocket in myoglobin probed by Raman and near-infrared absorption spectroscopy. AB - The influence of high pressure on the heme protein conformation of myoglobin in different ligation states is studied using Raman spectroscopy over the temperature range from 30 to 295 K. Photostationary experiments monitoring the oxidation state marker bands demonstrate the change of rebinding rate with pressure. While frequency changes of vibrational modes associated with rigid bonds of the porphyrin ring are <1 cm(-1), we investigate a significant shift of the iron-histidine mode to higher frequency with increasing pressure (approximately 3 cm(-1) for deltaP = 190 MPa in Mb). The observed frequency shift is interpreted structurally as a conformational change affecting the tilt angle between the heme plane and the proximal histidine and the out-of-plane iron position. Independent evidence for iron motion comes from measurements of the redshift of band III in the near-infrared with pressure. This suggests that at high pressure the proximal heme pocket and the protein are altered toward the bound state conformation, which contributes to the rate increase for CO binding. Raman spectra of Mb and photodissociated MbCO measured at low temperature and variable pressure further support changes in protein conformation and are consistent with glasslike properties of myoglobin below 160 K. PMID- 9370468 TI - Dynamic properties of monomeric insect erythrocruorin III from Chironomus thummi thummi: relationships between structural flexibility and functional complexity. AB - We have investigated the kinetics of geminate carbon monoxide binding to the monomeric component III of Chironomus thummi-thummi erythrocruorin, a protein that undergoes pH-induced conformational changes linked to a pronounced Bohr effect. Measurements were performed from cryogenic temperatures to room temperature in 75% glycerol and either 0.1 M potassium phosphate (pH 7) or 0.1 potassium borate (pH 9) after nanosecond laser photolysis. The distributions of the low temperature activation enthalpy g(H) for geminate ligand binding derived from the kinetic traces are quite narrow and are influenced by temperature both below and above approximately 170 K, the glass transition temperature. The thermal evolution of the CO binding kinetics between approximately 50 K and approximately 170 K indicates the presence of some degree of structural relaxation, even in this temperature range. Above approximately 220 K the width of the g(H) progressively decreases, and at 280 K geminate CO binding becomes exponential in time. Based on a comparison with analogous investigations of the homodimeric hemoglobin from Scapharca inaequivalvis, we propose a link between dynamic properties and functional complexity. PMID- 9370470 TI - Myoglobin and hemoglobin rotational diffusion in the cell. AB - The detection of the 1H NMR signal of myoglobin (Mb) in tissue opens an opportunity to examine its cellular diffusion property, which is central to its purported role in facilitating oxygen transport. In perfused myocardium the field dependent transverse relaxation analysis of the deoxy Mb proximal histidyl NdeltaH indicates that the Mb rotational correlation time in the cell is only approximately 1.4 times longer than it is in solution. Such a mobility is consistent with the theory that Mb facilitates oxygen diffusion from the sarcoplasm to the mitochondria. The microviscosities of the erythrocyte and myocyte environment are different. The hemoglobin (Hb) rotational correlation time is 2.2 longer in the cell than in solution. Because both the overlapping Hb and Mb signals are visible in vivo, a relaxation-based NMR strategy has been developed to discriminate between them. PMID- 9370471 TI - Quantitative spatially resolved measurements of mass transfer through laryngeal cartilage. AB - The scanning electrochemical microscope (SECM) is a scanned probe microscope that uses the response of a mobile ultramicroelectrode (UME) tip to determine the reactivity, topography, and mass transport characteristics of interfaces with high spatial resolution. SECM strategies for measuring the rates of solute diffusion and convection through samples of cartilage, using amperometric UMEs, are outlined. The methods are used to determine the diffusion coefficients of oxygen and ruthenium(III) hexamine [Ru(NH3)6(3+)] in laryngeal cartilage. The diffusion coefficient of oxygen in cartilage is found to be approximately 50% of that in aqueous electrolyte solution, assuming a partition coefficient of unity for oxygen between cartilage and aqueous solution. In contrast, diffusion of Ru(NH3)6(3+) within the cartilage sample cannot be detected on the SECM timescale, suggesting a diffusion coefficient at least two orders of magnitude lower than that in solution, given a measured partition coefficient for Ru(NH3)6(3+) between cartilage and aqueous solution, Kp = [Ru(NH3)6(3+)]cartilage/[RU(NH3)6(3+)]solution = 3.4 +/- 0.1. Rates of Ru(NH3)6(3+) osmotically driven convective transport across cartilage samples are imaged at high spatial resolution by monitoring the current response of a scanning UME, with an osmotic pressure of approximately 0.75 atm across the slice. A model is outlined that enables the current response to be related to the local flux. By determining the topography of the sample from the current response with no applied osmotic pressure, local transport rates can be correlated with topographical features of the sample surface, at much higher spatial resolution than has previously been achieved. PMID- 9370472 TI - Use of the green fluorescent protein and its mutants in quantitative fluorescence microscopy. AB - We have investigated properties relevant to quantitative imaging in living cells of five green fluorescent protein (GFP) variants that have been used extensively or are potentially useful. We measured the extinction coefficients, quantum yields, pH effects, photobleaching effects, and temperature-dependent chromophore formation of wtGFP, alphaGFP (F99S/M153T/V163A), S65T, EGFP (F64L/S65T), and a blue-shifted variant, EBFP (F64L/S65T/Y66H/Y145F). Absorbance and fluorescence spectroscopy showed little difference between the extinction coefficients and quantum yields of wtGFP and alphaGFP. In contrast, S65T and EGFP extinction coefficients made them both approximately 6-fold brighter than wtGFP when excited at 488 nm, and EBFP absorbed more strongly than the wtGFP when excited in the near-UV wavelength region, although it had a much lower quantum efficiency. When excited at 488 nm, the GFPs were all more resistant to photobleaching than fluorescein. However, the wtGFP and alphaGFP photobleaching patterns showed initial increases in fluorescence emission caused by photoconversion of the protein chromophore. The wtGFP fluorescence decreased more quickly when excited at 395 nm than 488 nm, but it was still more photostable than the EBFP when excited at this wavelength. The wtGFP and alphaGFP were quite stable over a broad pH range, but fluorescence of the other variants decreased rapidly below pH 7. When expressed in bacteria, chromophore formation in wtGFP and S65T was found to be less efficient at 37 degrees C than at 28 degrees C, but the other three variants showed little differences between 37 degrees C and 28 degrees C. In conclusion, no single GFP variant is ideal for every application, but each one offers advantages and disadvantages for quantitative imaging in living cells. PMID- 9370473 TI - Coupled plasmon-waveguide resonators: a new spectroscopic tool for probing proteolipid film structure and properties. AB - A variant of surface plasmon resonance (SPR) spectroscopy has been developed that involves a coupling of plasmon resonances in a thin metal film and waveguide modes in a dielectric overcoating. This new technique is referred to as coupled plasmon-waveguide resonance (CPWR) spectroscopy. It combines a greatly enhanced sensitivity (due to increased electromagnetic field intensities at the dielectric surface) and spectral resolution (due to decreased resonance linewidths), with the ability to directly measure anisotropies in refractive index and optical absorption coefficient in a dielectric film adsorbed onto the surface of the overcoating. Experimental data obtained with an egg phosphatidylcholine bilayer are presented to document these properties. PMID- 9370474 TI - Viscoelastic response of fibroblasts to tension transmitted through adherens junctions. AB - Cytoplasmic deformation was monitored by observing the displacements of 200-nm green fluorescent beads microinjected into the cytoplasm of Swiss 3T3 fibroblasts. We noted a novel protrusion of nonruffling cell margins that was accompanied by axial flow of beads and cytoplasmic vesicles as far as 50 microm behind the protruding plasma membrane. Fluorescent analog cytochemistry and immunofluorescence localization of F-actin, alpha-actinin, N-cadherin, and beta catenin showed that the protruding margins of deforming cells were mechanically coupled to neighboring cells by adherens junctions. Observations suggested that protrusion resulted from passive linear deformation in response to tensile stress exerted by centripetal contraction of the neighboring cell. The time dependence of cytoplasmic strain calculated from the displacements of beads and vesicles was fit quantitatively by a Kelvin-Voight model for a viscoelastic solid with a mean limiting strain of 0.58 and a mean strain rate of 4.3 x 10(-3) s(-1). In rare instances, the deforming cell and its neighbor spontaneously became uncoupled, and recoil of the protruding margin was observed. The time dependence of strain during recoil also fit a Kelvin-Voight model with similar parameters, suggesting that the kinetics of deformation primarily reflect the mechanical properties of the deformed cell rather than the contractile properties of its neighbor. The existence of mechanical coupling between adjacent fibroblasts through adherens junctions and the viscoelastic responses of cells to tension transmitted directly from cell to cell are factors that must be taken into account to fully understand the role of fibroblasts in such biological processes as wound closure and extracellular matrix remodeling during tissue development. PMID- 9370475 TI - Effect of diamide on force generation and axial stiffness of the cochlear outer hair cell. AB - We found that diamide, which affects spectrin, reduces the axial stiffness of the cochlear outer hair cell, the cylindrically shaped mechanoreceptor cell with a unique voltage-sensitive motility. This effect thus provides a means of examining the relationship between the stiffness and the motility of the cell. For measuring axial stiffness and force production, we used an experimental configuration in which an elastic probe was attached to the cell near the cuticular plate and the other end of the cell was held with a patch pipette in the whole-cell recording mode. Diamide at concentrations of up to 5 mM reduced the axial stiffness in a dose-dependent manner to 165 nN per unit strain from 502 nN for untreated cells. The isometric force elicited by voltage pulses under whole-cell voltage clamp was also reduced to 35 pN/mV from 105 pN/mV for untreated cells. Thus the isometric force was approximately proportional to the axial stiffness. Our observations suggest a series connection between the motor and cytoskeletal elements and can be explained by the area motor model previously proposed for the outer hair cell. PMID- 9370476 TI - Hydrodynamic effects and receptor interactions of platelets and their aggregates in linear shear flow. AB - We have modeled platelet aggregation in a linear shear flow by accounting for two body collision hydrodynamics, platelet activation and receptor biology. Considering platelets and their aggregates as unequal-sized spheres with DLVO interactions (psi(platelet) = -15 mV, Hamaker constant = 10(-19) J), detailed hydrodynamics provided the flow field around the colliding platelets. Trajectory calculations were performed to obtain the far upstream cross-sectional area and the particle flux through this area provided the collision frequency. Only a fraction of platelets brought together by a shearing fluid flow were held together if successfully bound by fibrinogen cross-bridging GPIIb/IIIa receptors on the platelet surfaces. This fraction was calculated by modeling receptor mediated aggregation using the formalism of Bell (Bell, G. I. 1979. A theoretical model for adhesion between cells mediated by multivalent ligands. Cell Biophys. 1:133-147) where the forward rate of bond formation dictated aggregation during collision and was estimated from the diffusional limited rate of lateral association of receptors multiplied by an effectiveness factor, eta, to give an apparent rate. For a value of eta = 0.0178, we calculated the overall efficiency (including both receptor binding and hydrodynamics effects) for equal-sized platelets with 50,000 receptors/platelet to be 0.206 for G = 41.9 s(-1), 0.05 for G = 335 s(-1), and 0.0086 for G = 1920 s(-1), values which are in agreement with efficiencies determined from initial platelet singlet consumption rates in flow through a tube. From our analysis, we predict that bond formation proceeds at a rate of approximately 0.1925 bonds/microm2 per ms, which is approximately 50-fold slower than the diffusion limited rate of association. This value of eta is also consistent with a colloidal stability of unactivated platelets at low shear rates. Fibrinogen was calculated to mediate aggregation quite efficiently at low shear rates but not at high shear rates. Although secondary collisions (an orbitlike trajectory) form only a small fraction of the total number of collisions, they become important at high shear rates (>750 s(-1)), as these are the only collisions that provide enough time to result in successful aggregate formation mediated by fibrinogen. The overall method provides a hydrodynamic and receptor correction of the Smoluchowski collision kernel and gives a first estimate of eta for the fibrinogen-GPIIb/IIIa cross-bridging of platelets. We also predict that secondary collisions extend the shear rate range at which fibrinogen can mediate successful aggregation. PMID- 9370478 TI - A piece of my mind. Farewell to his craft. PMID- 9370479 TI - NCQA: quality through evaluation. National Committee for Quality Assurance. PMID- 9370477 TI - Mapping fluorophore distributions in three dimensions by quantitative multiple angle-total internal reflection fluorescence microscopy. AB - The decay of evanescent field intensity beyond a dielectric interface depends upon beam incident angle, enabling the 3-d distribution of fluorophores to be deduced from total internal reflection fluorescence microscopy (TIRFM) images obtained at multiple incident angles. Instrumentation was constructed for computer-automated multiple angle-TIRFM (MA-TIRFM) using a right angle F2 glass prism (n(r) 1.632) to create the dielectric interface. A laser beam (488 nm) was attenuated by an acoustooptic modulator and directed onto a specified spot on the prism surface. Beam incident angle was set using three microstepper motors controlling two rotatable mirrors and a rotatable optical flat. TIRFM images were acquired by a cooled CCD camera in approximately 0.5 degree steps for >15 incident angles starting from the critical angle. For cell studies, cells were grown directly on the glass prisms (without refractive index-matching fluid) and positioned in the optical path. Images of the samples were acquired at multiple angles, and corrected for angle-dependent evanescent field intensity using "reference" images acquired with a fluorophore solution replacing the sample. A theory was developed to compute fluorophore z-distribution by inverse Laplace transform of angle-resolved intensity functions. The theory included analysis of multiple layers of different refractive index for cell studies, and the anisotropic emission from fluorophores near a dielectric interface. Instrument performance was validated by mapping the thickness of a film of dihexyloxacarbocyanine in DMSO/water (n(r) 1.463) between the F2 glass prism and a plano-convex silica lens (458 mm radius, n(r) 1.463); the MA-TIRFM map accurately reproduced the lens spherical surface. MA-TIRFM was used to compare with nanometer z-resolution the geometry of cell-substrate contact for BCECF labeled 3T3 fibroblasts versus MDCK epithelial cells. These studies establish MA TIRFM for measurement of submicroscopic distances between fluorescent probes and cell membranes. PMID- 9370480 TI - Revitalized AHCPR pursues research on quality. Agency for Health Care Policy and Research. PMID- 9370481 TI - A FACCT-filled agenda for public information. Foundation for Accountability. PMID- 9370482 TI - HCFA focuses on new plans for quality care. Health Care Financing Administration. PMID- 9370483 TI - IHI views collaboration vs competition in quality. Institute for Healthcare Improvement. PMID- 9370484 TI - National Patient Safety Foundation studies systems. PMID- 9370485 TI - Joint Commission begins tracking outcome data. PMID- 9370486 TI - From the Centers for Disease Control and Prevention. National Diabetes Awareness Month--November 1997. PMID- 9370487 TI - From the Centers for Disease Control and Prevention. Trends in the prevalence and incidence of self-reported diabetes mellitus--United States, 1980-1994. PMID- 9370488 TI - From the Centers for Disease Control and Prevention. Availability of diabetes information on the Internet. PMID- 9370489 TI - Personal use of drug samples by physicians and office staff. PMID- 9370490 TI - Personal use of drug samples by physicians and office staff. PMID- 9370491 TI - Personal use of drug samples by physicians and office staff. PMID- 9370492 TI - Personal use of drug samples by physicians and office staff. PMID- 9370494 TI - Personal use of drug samples by physicians and office staff. PMID- 9370493 TI - Personal use of drug samples by physicians and office staff. PMID- 9370495 TI - Personal use of drug samples by physicians and office staff. PMID- 9370496 TI - Humanitarianism survives, despite being under the gun. PMID- 9370497 TI - Risk of hypoglycemia with antihypertensive medication. PMID- 9370498 TI - Risk of hypoglycemia with antihypertensive medication. PMID- 9370499 TI - Graduate medical education and government oversight. PMID- 9370500 TI - Role of the nurse practitioner in mental health services. PMID- 9370501 TI - Losartan-induced hepatotoxicity. PMID- 9370502 TI - Peer review of the quality of care. Reliability and sources of variability for outcome and process assessments. AB - CONTEXT: Peer assessments have traditionally been used to judge the quality of care, but a major drawback has been poor interrater reliability. OBJECTIVES: To compare the interrater reliability for outcome and process assessments in a population of frail older adults and to identify systematic sources of variability that contribute to poor reliability. SETTING: Eight sites participating in a managed care program that integrates acute and long-term care for frail older adults. PATIENTS: A total of 313 frail older adults. DESIGN: Retrospective review of the medical record with 180 charts randomly assigned to 2 geriatricians, 2 geriatric nurse practitioners, or 1 geriatrician and 1 geriatric nurse practitioner and 133 charts randomly assigned to either a geriatrician or a geriatric nurse practitioner. MAIN OUTCOME MEASURES: Interrater reliabilities for structured implicit judgments about process and outcomes for overall care and care for each of 8 tracer conditions (eg, arthritis). RESULTS: Outcome measures had higher interrater reliability than process measures. Five outcome measures achieved fair to good reliability (more than 0.40), while none of the process measures achieved reliabilities more than 0.40. Three factors contributed to poorer reliabilities for process measures: (1) an inability of reviewers to differentiate among cases with respect to the quality of management, (2) systematic bias from individual reviewers, and (3) systematic bias related to the professional training of the reviewer (ie, physician or nurse practitioner). CONCLUSIONS: Peer assessments can play an important role in characterizing the quality of care for complex patients with multiple interrelated chronic conditions, but reliability can be poor. Strategies to achieve adequate reliability for these assessments should be applied. These strategies include emphasizing outcomes measurement, providing more structured assessments to identify true differences in patient management, adjusting systematic bias resulting from the individual reviewer and their professional background, and averaging scores from multiple reviewers. Future research on the reliability of peer assessments should focus on improving the ability of process measures to differentiate among cases with respect to the quality of management and on identifying additional sources of systematic bias for both process and outcome measures. Explicit recognition of factors influencing reliability will strengthen efforts to develop sound measures for quality assurance. PMID- 9370503 TI - Consumer reports in health care. Do they make a difference in patient care? AB - CONTEXT: Consumer reports in health care are a relatively recent phenomenon. Primarily designed to assist consumers in making more informed decisions about their personal health care, they appear to have an important by-product-they led to positive changes in the behavior of clinicians and health care delivery organizations. While there has been much speculation on their impact on health care consumer behavior, consumer reports offer an effective strategy in improving the quality of patient care. OBJECTIVE: To examine the impact of an obstetrics consumer report developed and issued by the Missouri Department of Health on hospital behavior. DESIGN AND SETTING: A retrospective study of hospital behavior using both primary survey and secondary clinical data. PARTICIPANTS: Consumer reports were issued in 1993 to all Missouri hospitals providing obstetrical services (n=90). A survey was conducted a year later, and the results were analyzed with other available data to determine the effect of the report. Two hospitals discontinued obstetrical services by the time of the survey; of the remaining 88 hospitals, 82 (93%) responded to the survey. MAIN OUTCOME MEASURES: The following outcomes were examined: (1) number and percentage of hospitals that previously did not have services at the time report was issued, but had, or planned to have, services after a guide was published; (2) the percentage of obstetrical policies that were changed, planned to change, or are under discussion for change (car seat program, obstetrical follow-up services, formal transfer agreement, nurse educator for breast-feeding, and availability of tubal ligations); and (3) clinical outcomes, including satisfaction, appropriateness of charges, and the rates of cesarean delivery, high-risk infant transfer, ultrasound, vaginal birth after cesarean, very low birth weight, and newborn death. RESULTS: Within 1 year of the report, approximately 50% of hospitals that did not have car seat programs, formal transfer agreements, or nurse educators for breast-feeding prior to the report either instituted or planned to institute these services. Hospitals in competitive markets that did not offer one of these services at the time of the report were more likely to institute a service and/or were about twice as likely to consider improving several indicators. Clinical outcome indicators all improved in the expected direction. CONCLUSION: Public release of consumer reports may be useful not only in assisting consumers to make informed health care choices, but also in facilitating improvement in the quality of hospital services offered and care provided. Changes occur especially in competitive markets. PMID- 9370504 TI - Implementation of clinical guidelines using a computer charting system. Effect on the initial care of health care workers exposed to body fluids. AB - CONTEXT: While clinical guidelines are considered an important mechanism to improve the quality of medical care, problems with implementation may limit their effectiveness. Few empirical data exist about the effect of computer-based systems for application of clinical guidelines on quality of care. OBJECTIVE: To determine whether real-time presentation of clinical guidelines using an electronic medical record can increase compliance with guidelines. DESIGN: Prospective off-on-off, interrupted time series with intent-to-treat analysis. SETTING: University hospital emergency department. SUBJECTS: Patients were 280 health care workers (50 in the baseline control phase, 156 in the intervention phase, and 74 in the postintervention control phase) who presented for initial treatment of occupational body fluid exposures, including 89% (248/280) who sustained punctures and 81% (208/257) who were exposed to blood. Physicians included resident physicians and attending physicians working in the emergency department during the study. INTERVENTIONS: Implementation of a computer charting system that provides real-time information regarding history and recommendations for laboratory testing, treatment, and disposition based on rules derived from clinical guidelines. MAIN OUTCOME MEASURES: Quality of care as determined by essential items documented in the medical record and in aftercare instructions, compliance with testing and treatment guidelines, and total charges and percentage of charges attributable to guideline-endorsed activities. RESULTS: Mean percent documentation of 7 essential items regarding patient history in the medical record increased from 57% during the baseline period to 98% in the intervention phase (42% increase; 95% confidence interval [CI], 34%-49%) and 11 items in aftercare instruction increased from 31 % at baseline to 93% during the intervention phase (62% increase; 95% CI, 51%-74%), but both decreased to baseline when the computer system was removed. Percent compliance with 4 laboratory testing guidelines increased from 63% at baseline to 83% during the intervention phase (20% increase; 95% CI, 9%-31 %) but decreased to 52% when the computer system was removed. Compliance with 5 treatment guidelines increased from 83% at baseline to 96% during the intervention phase (13% increase; 95% CI, 9%-17%) and decreased to 84% following the intervention. Percentage of charges incurred for indicated laboratory tests and treatment increased from 44% at baseline to 81% during the intervention phase (37% increase; 95% CI, 22%-52%) and decreased to 36% following the intervention. Average total per-patient charges were $460, $384, and $373 in each phase, respectively. CONCLUSIONS: Use of a computer-based system for clinical guidelines for management of patients with occupational exposure to body fluids improved documentation, compliance with guidelines, and percentage of charges spent on indicated activities, while decreasing overall charges. The parameters returned to baseline when the computer system was removed. PMID- 9370505 TI - Impact of a clinical guidelines program for breast and colon cancer in a French cancer center. AB - CONTEXT: Between 1993 and 1994, the 80 physicians in the French comprehensive cancer center, Leon Berard, developed and implemented a Clinical Practice Guidelines (CPGs) project based on an analysis of the literature and a consensus of intrainstitutional experts. OBJECTIVE: The aims of this project are to assist community-based oncologists in their decision making and to minimize inappropriate variation in practices. A study was designed to assess the impact of CPGs on management of breast and colon cancer. DESIGN: A "before-after" study, using institutional computerized records of patients with breast or colon cancer. SETTING: Records for 100 women with localized breast cancer were randomly selected from those available in 1993 and 1995, and those for all patients newly referred with colon cancer in 1993 and 1995 (77 and 81 patients, respectively). Medical decisions on these records were analyzed to assess their compliance with the CPGs. (A systematic search of the literature was performed to determine the scientific evidence for noncompliant decisions.) RESULTS: Of 375 available medical decisions, 350 were assessable. The compliance rate with CPGs for breast cancer was significantly higher in 1995 compared with 1993, 54% (54/99; 95% confidence interval [CI], 44%-64%) vs 19% (18/95; 95% CI, 11%-27%) (P<.001). The compliance rate for colon cancer was also significantly higher in 1995 than in 1993, 70% (62/88; 95% CI, 60%-80%) vs 50% (34/ 68; 95% CI, 38%-62%) (P=.009). In 1993, 42% (40/95; 95% CI, 32%-52%) of medical decisions for breast cancer and in 1995, 68% (67/99; 95% CI, 59%-77%) conformed with the CPGs or were judged to be based on "scientific evidence." In 1993, 71% (48/68; 95% CI, 60%-81%) of medical decisions for colon cancer, and in 1995 81% (71/88; 95% CI, 73%-89%) conformed with the CPGs or were judged to be based on scientific evidence. CONCLUSIONS: Compliance rates were significantly higher in 1995 for both cancers. The development and implementation of CPGs for cancer management seem to result in significant changes in medical practice, although a causal relationship between changes and CPGs is not demonstrated in this study. PMID- 9370506 TI - Choice of a personal physician and patient satisfaction in a health maintenance organization. AB - CONTEXT: Being able to choose one's health care plan has been shown to increase subsequent patient satisfaction with the plan, but it is not known whether choosing one's own primary care physician affects patient satisfaction with the physician. OBJECTIVE: To compare satisfaction with care between members of a group-model health maintenance organization (HMO) who chose their primary care physician and members who were assigned a physician. DESIGN: Cross-sectional mailed survey with response rate of 71.4%. SETTING: A large group-model HMO in northern California. MAIN OUTCOME MEASURE: Nine questions on satisfaction with the primary care physician. SUBJECTS: Random sample of HMO members 35 to 85 years of age who were impaneled with a primary care physician. RESULTS: Among the 10205 survey respondents, patients who chose their personal physician (n=4748) were 16 to 20 percentage points more likely to rate their satisfaction as "excellent" or "very good" than patients who were assigned a physician (n =5457) for 9 satisfaction measures (P<.001 for each comparison). The association of choice with satisfaction was not due to physicians with higher patient satisfaction being chosen more often, or to differences in patient demographic or socioeconomic characteristics, health values, or health beliefs, or to differences in physician demographics or specialty. In a logistic regression model that adjusted for all of these characteristics, having chosen one's physician was the single predictor most strongly related to having high overall satisfaction (odds ratio, 2.18, 95% confidence interval, 1.95-2.42). CONCLUSION: These results suggest that even in a setting of limited physician choice, the opportunity to select one's personal physician may influence subsequent satisfaction. PMID- 9370507 TI - The risks of risk adjustment. AB - CONTEXT: Risk adjustment is essential before comparing patient outcomes across hospitals. Hospital report cards around the country use different risk adjustment methods. OBJECTIVES: To examine the history and current practices of risk adjusting hospital death rates and consider the implications for using risk adjusted mortality comparisons to assess quality. DATA SOURCES AND STUDY SELECTION: This article examines severity measures used in states and regions to produce comparisons of risk-adjusted hospital death rates. Detailed results are presented from a study comparing current commercial severity measures using a single database. It included adults admitted for acute myocardial infarction (n=11880), coronary artery bypass graft surgery (n=7765), pneumonia (n=18016), and stroke (n=9407). Logistic regressions within each condition predicted in hospital death using severity scores. Odds ratios for in-hospital death were compared across pairs of severity measures. For each hospital, z scores compared actual and expected death rates. RESULTS: The severity measure called Disease Staging had the highest c statistic (which measures how well a severity measure discriminates between patients who lived and those who died) for acute myocardial infarction, 0.86; the measure called All Patient Refined Diagnosis Related Groups had the highest for coronary artery bypass graft surgery, 0.83; and the measure, MedisGroups, had the highest for pneumonia, 0.85 and stroke, 0.87. Different severity measures predicted different probabilities of death for many patients. Severity measures frequently disagreed about which hospitals had particularly low or high z scores. Agreement in identifying low- and high-mortality hospitals between severity-adjusted and unadjusted death rates was often better than agreement between severity measures. CONCLUSIONS: Severity does not explain differences in death rates across hospitals. Different severity measures frequently produce different impressions about relative hospital performance. Severity-adjusted mortality rates alone are unlikely to isolate quality differences across hospitals. PMID- 9370508 TI - Health care quality. Incorporating consumer perspectives. AB - The goal of this article is to address, from the perspective of users of the health care system (consumers), the following questions: What are the most important health care quality gaps and/or challenges; what major changes should we anticipate in this area in the near future; and what should be the role of federal and state agencies, accreditation organizations, and philanthropic foundations in addressing these challenges? We discuss the needs, challenges, and potential action steps for increasing the prominence of the user's perspective in 3 areas: (1) the conceptualization and definition of quality; (2) the measurement of quality; and (3) routine quality assessment and improvement. The article concludes by making recommendations about the role that different agencies and organizations can and should play in meeting these challenges. PMID- 9370509 TI - Managed care is not the problem, quality is. PMID- 9370510 TI - Medicaid managed care and high quality. Can we have both? PMID- 9370511 TI - The future of quality measurement and management in a transforming health care system. PMID- 9370512 TI - Defining goals and conditions for a sustainable world. AB - Sustainable development is being approached component by component- socioeconomic, sustainable agriculture, transportation, forestry, energy use, cities, and the like--but, leaving a habitable planet for future generations will require the development of a widely shared paradigm. Further, the paradigm should be ecological from a scientific point of view. This development will be facilitated by a discussion of goals and those conditions necessary to meet them. The presently shared paradigm is that economic growth is the cure for all of society's problems, such as poverty, overpopulation, environmental degradation, and the increasing gap between rich and poor. A paradigm shift from growth to sustainability might result either from suffering painful consequences of continuing to follow out-moded paradigms or by discussing what sort of ecosystems will be available to future generations. The purpose of this paper is to help initiate such a discussion. PMID- 9370513 TI - The significance of mouse liver tumor formation for carcinogenic risk assessment: results and conclusions from a survey of ten years of testing by the agrochemical industry. AB - A survey was performed on the results of 138 carcinogenicity studies conducted in various mouse strains by the agrochemical industry over the period 1983-1993. Data for liver tumor incidence, liver weight, and histopathology were collected along with data on genotoxicity. Studies were judged positive or negative for liver tumor formation on the basis of apparent dose response, malignancy, and difference from historical control values using a weight of evidence approach. Thirty-seven studies were judged to be positive for liver tumorigenicity in one or both sexes. There was no evidence showing an influence of the mouse strain and the duration of the study on the proportion of positive studies. Although 8 of the chemicals tested in the 138 studies were positive in the Ames test, only one of these was judged positive for carcinogenicity. Only 6 of the 37 positive chemicals had any other reported positive genotoxicity findings. A clear relationship between hepatomegaly at 1 year after exposure and a positive tumorigenic outcome at 18 months or 2 years after exposure was demonstrated. Whereas the average relative liver weight of top dose animals was 110% of control in negative studies, it was 150% in positive studies. Likewise, very few negative studies demonstrated significant pathological findings after 1 year, whereas the majority of positive studies had significant liver pathology. The implications of these findings for extrapolation to humans are discussed. PMID- 9370514 TI - Bovine spongiform encephalopathy: is it an autoimmune disease due to bacteria showing molecular mimicry with brain antigens? AB - Bovine spongiform encephalopathy (BSE) could be an autoimmune disease produced following exposure of cattle to feedstuffs containing bacteria showing molecular mimicry between bacterial components and bovine tissue. Analysis of molecular sequence databases (Genbank and SwissProt) shows that three bacteria (Acinetobacter calcoaceticus,Ruminococcus albus, and Agrobacter tumefaciens) share sequences with the encephalitogenic peptide of bovine myelin, while three molecules in Escherichia coli show molecular mimicry with host-encoded prion protein. Immune responses against these bacteria at both T and B cell levels may cause neurological tissue injury resembling BSE. The role of these bacteria in BSE, if any, merits further investigation. PMID- 9370516 TI - Seeing the forests for the more than the trees. AB - Assessing the health effects of deforestation is difficult because of the rate at which the world's forests are disappearing. From 1990 to 1995 alone, the world lost a total area of forest cover nearly twice the size of Italy. Deforestation, which is caused by human population growth and encroachment, clearance for agricultural production, and the growing worldwide demand for wood products, has been linked with effects ranging from local changes in climatic and disease patterns to global climate change and biodiversity loss. Deforestation is responsible for about 25% of net annual releases of carbon dioxide into the atmosphere and also lessens the amount of forest available to absorb greenhouse gas emissions. Deforestation also causes a tremendous loss of biodiversity worldwide. It is estimated that over the next 50 years deforestation will rank as the single greatest cause of species loss. PMID- 9370518 TI - Working the bugs out of asthma. AB - Cockroach antigens (proteins found in the insects' feces, saliva, eggs, and shed cuticles) have been implicated as one of the leading causes of asthma among inner city children. These antigens can trigger severe allergic reactions, and even tiny amounts can be potentially fatal to sensitive asthmatics. PMID- 9370517 TI - Analysis of breast milk to assess exposure to chlorinated contaminants in Kazakstan: PCBs and organochlorine pesticides in southern Kazakstan. AB - Organochlorine pesticides (OC) and polychlorinated biphenyls (PCBs) were measured in samples of breast milk taken from 92 donors representative of regional populations in southern Kazakstan. The World Health Organization protocol for assessing levels of chlorinated contaminants in breast milk was followed. The most prevalent OC residues were beta-hexachlorocyclohexane (beta-HCH), p,p'-DDE, p,p'-DDT, hexachlorobenzene, and alpha-HCH. The measured levels of beta-HCH were among the highest reported in the published literature. Data from Aralsk, near the Aral Sea, indicated continuing DDT exposure. Overall PCB-toxic equivalent levels (22 pg/g fat) were similar to those reported in industrialized European countries. PCBs were highest in Atyrau in the Caspian oilfields. PMID- 9370515 TI - Examination of the estrogenicity of 2,4,6,2',6'-pentachlorobiphenyl (PCB 104), its hydroxylated metabolite 2,4,6,2',6'-pentachloro-4-biphenylol (HO-PCB 104), and a further chlorinated derivative, 2,4,6,2',4',6'-hexachlorobiphenyl (PCB 155). AB - Several studies have reported that polychlorinated biphenyls (PCBs) exhibit estrogenic activity; however, it is not clear if these responses are associated with the polychlorinated hydrocarbon or its hydroxylated metabolite. In order to further test this hypothesis, a battery of in vitro and in vivo assays were used to investigate the estrogenic and antiestrogenic activities of 2,4,6,2',6' pentachlorobiphenyl (PCB 104), its para-hydroxylated derivative 2,4,6,2',6' pentachloro-4-biphenylol (HO-PCB 104), and its para-chlorinated derivative 2,4,6,2',4',6'-hexachlorobiphenyl (PCB 155). PCB 104 was found to 1) compete with tritiated 17beta-estradiol (E2) for binding to the mouse uterine estrogen receptor (ER); 2) induce gene expression in MCF-7 human breast cancer cells transiently transfected with the Gal4-human ER chimeric construct (Gal4-HEGO) and the Gal4-regulated luciferase reporter gene (17m5-G-Luc); and 3) increase MCF-7 cell proliferation in a dose-dependent manner. HO-PCB 104 exhibited greater estrogenic activity than PCB 104 in the in vitro assays examined. However, gas chromatographic-mass spectrophotometric analysis of extracts prepared from MCF-7 cells incubated with PCB 104 failed to detect the presence of the expected major metabolite HO-PCB 104. The estrogenic activity of the para-chlorinated derivative, PCB 155, was minimal compared to PCB 104 and HO-PCB 104, but it did exhibit significant antiestrogenic activity following co-treatment with 1 nM E2. Co-treatment of PCB 104 with 1 nM E2 had no effect on reporter gene expression compared to E2 alone, while 10 microM HO-PCB 104 exhibited additivity with 1 nM E2. At a dose of 202 mg/kg,PCB 104 increased uterine wet weight in ovariectomized CD-1 mice and induced vaginal epithelial cell cornification at 202, 16, and 1.7 mg/kg in a dose-dependent manner. These studies demonstrate that in addition to the hydroxylated metabolites, selected parent PCB congeners may also exhibit estrogenic and antiestrogenic activities. PMID- 9370519 TI - Triazine herbicide exposure and breast cancer incidence: an ecologic study of Kentucky counties. AB - The incidence of breast cancer in the United States has steadily increased for the past three decades. Exposure to excess estrogen, in both natural and synthetic forms, has been implicated as a risk factor for the development of this disease. Considerable interest has been focused on organochlorines, such as the triazine herbicides, and their possible role in the initiation or promotion of human breast cancer. To explore this relationship, an ecologic study of Kentucky counties was designed. Exposure to triazines was estimated by use of water contamination data, corn crop production, and pesticide use data. A summary index of triazine herbicide exposure was developed to classify counties into low, medium, or high exposure levels. Data on county breast cancer rates were obtained from the state registry. A Poisson regression analysis was performed, controlling for age, race, age at first live birth, income, and level of education. Results revealed a statistically significant increase in breast cancer risk with medium and high levels of triazine exposure [odds ratio (OR) = 1.14,p<0.0001 and OR = 1.2, p<0.0001, respectively]. The results suggest a relationship between exposure to triazine herbicides and increased breast cancer risk, but conclusions concerning causality cannot be drawn, due to the limitations inherent in ecologic study design. PMID- 9370520 TI - Human pulmonary responses to experimental inhalation of high concentration fine and ultrafine magnesium oxide particles. AB - Exposure to air polluted with particles less than 2.5 micron in size is associated epidemiologically with adverse cardiopulmonary health consequences in humans. The goal of this study was to characterize human pulmonary responses to controlled experimental high-dose exposure to fine and ultrafine magnesium oxide particles. We quantified bronchoalveolar lavage (BAL) cell and cytokine concentrations, pulmonary function, and peripheral blood neutrophil concentrations in six healthy volunteers 18 to 20 hr after inhalation of fine and ultrafine magnesium oxide particles produced from a furnace system model. We compared postexposure studies with control studies from the same six subjects. Mean +/- standard deviation (SD) cumulative magnesium dose was 4,138 +/- 2,163 min x mg/m3. By weight, 28% of fume particles were ultrafine (<0.1 micron in diameter) and over 98% of fume particles were fine (<2.5 micron in diameter). There were no significant differences in BAL inflammatory cell concentrations, BAL interleukin (IL)-1, IL-6, IL-8, tumor necrosis factor, pulmonary function, or peripheral blood neutrophil concentrations postexposure compared with control. Our findings suggest that high-dose fine and ultrafine magnesium oxide particle exposure does not produce a measurable pulmonary inflammatory response. These findings are in marked contrast with the well-described pulmonary inflammatory response following zinc oxide particle inhalation. We conclude that fine and ultrafine particle inhalation does not result in toxicity in a generic manner independent of particle composition. Our findings support the concept that particle chemical composition, in addition to particle size, is an important determinant of respiratory effects. PMID- 9370521 TI - Phenolphthalein-containing laxative use in relation to adenomatous colorectal polyps in three studies. AB - Phenolphthalein, the active ingredient in many laxatives, was recently found to be a carcinogen in animal models. Human data suggest a laxative-colon cancer association, but few data specifically address the effects of phenolthalein containing laxatives. We examined use of phenolphtalein-containing laxatives in relation to occurrence of adenomatous colorectal polyps in data from three case control studies. The study conducted in Los Angeles, California (1991-1993), and the two studies conducted in North Carolina (1988-1990 and 1992-1995) altogether included 866 cases and 1,066 controls. The prevalence of using phenolphthalein containing laxatives at least once a week in the recent past, however, was less than 5% among these subjects. The multivariate-adjusted odds ratios associated with recent use of phenolphthalein-containing laxatives once a week or more were 1.8 -95% confidence interval (CI), 0.5-6.2] in Los Angeles, 1.0 (CI, 0.4-2.2) in North Carolina (1988-1990), and 1.1 (CI, 0.2-5.7) in North Carolina (1992-1995). For use of other types of laxatives, the corresponding odds ratios were 1.3 (CI, 0.9-1.9) in Los Angeles, 1.0 (CI, 0.5-1.7) in North Carolina (1988-1990), and 0.9 (CI, 0.4-1.8) in North Carolina (1992-1995). Although the low prevalence of frequent use made for relatively wide confidence intervals, overall these data suggest that use of phenolphthalein-containing laxatives does not increase risk of adenomatous colorectal polyps. PMID- 9370522 TI - Household pesticides and risk of pediatric brain tumors. AB - A follow-up to a population-based case-control study of pediatric brain tumors in Los Angeles County, California, involving mothers of 224 cases and 218 controls, investigated the risk of household pesticide use from pregnancy to diagnosis. Risk was significantly elevated for prenatal exposure to flea/tick pesticides odds ratio (OR) = 1.7; 95% confidence interval (CI), 1.1-2.6-, particularly among subjects less than 5 years old at diagnosis (OR = 2.5; CI, 1. 2-5.5). Prenatal risk was highest for mothers who prepared, applied, or cleaned up flea/tick products themselves (OR = 2.2; CI, 1.1-4.2; for subjects <5 years of age, OR = 5.4; CI, 1.3-22.3). A significant trend of increased risk with increased exposure was observed for number of pets treated (p = 0.04). Multivariate analysis of types of flea/tick products indicated that sprays/foggers were the only products significantly related to risk (OR =10.8; CI, 1.3-89.1). Elevated risks were not observed for termite or lice treatments, pesticides for nuisance pests, or yard and garden insecticides, herbicides, fungicides, or snail killer. Certain precautions,if ignored, were associated with significant increased risk: evacuating the house after spraying or dusting for pests (OR = 1.6; CI, 1.0-2.6), delaying the harvest of food after pesticide treatment (OR = 3.6; CI, 1.0-13.7), and following instructions on pesticide labels (OR = 3. 7;CI, 1.5-9.6). These findings indicate that chemicals used in flea/tick products may increase risk of pediatric brain tumors and suggest that further research be done to pinpoint specific chemicals involved. PMID- 9370523 TI - Estimating xenobiotic half-lives in humans from rat data: influence of log P. AB - The nature of empirical allometric expressions relating dispositional and kinetic parameters for a given xenobiotic across multiple mammalian species is well known. It has also been demonstrated that a simple allometric relationship may be used to predict kinetic parameters for humans based merely on data for multiple xenobiotics from rats. We decided to explore reasons for the variance in the data arising from the latter method. We were particularly interested in learning whether any physicochemical characteristics of xenobiotics might account for outlying data points (i.e., poor prediction of human half-life from rat half life). We have explored the influence of lipid solubility as reflected by a xenobiotic's log P value because adipose tissue comprises a significantly larger percentage of total body weight in humans than in rats. We used half-life data from the literature for 127 xenobiotics. A data subset of 102 xenobiotics for which we were able to find estimates of log P values, including several with extremely large log P values, was also analyzed. First and second order models, including and excluding log P, were compared. The simplest of these models can be recast as the familiar allometric relationship having the form Y = a(Xb). The remaining models can be seen as extensions of this relationship. Our results suggest that incorporation of log P into the prediction of xenobiotic half-life in humans from rat half-life data is important only for xenobiotics with extremely large log P values such as dioxins and polychlorinated biphenyls. Moreover, a second order model in logarithm of rat half-life accommodates all data points very well, without specifically accounting for log P values. PMID- 9370525 TI - Approximation algorithms. AB - Increasing global competition, rapidly changing markets, and greater consumer awareness have altered the way in which corporations do business. To become more efficient, many industries have sought to model some operational aspects by gigantic optimization problems. It is not atypical to encounter models that capture 10(6) separate "yes" or "no" decisions to be made. Although one could, in principle, try all 2(10(6)) possible solutions to find the optimal one, such a method would be impractically slow. Unfortunately, for most of these models, no algorithms are known that find optimal solutions with reasonable computation times. Typically, industry must rely on solutions of unguaranteed quality that are constructed in an ad hoc manner. Fortunately, for some of these models there are good approximation algorithms: algorithms that produce solutions quickly that are provably close to optimal. Over the past 6 years, there has been a sequence of major breakthroughs in our understanding of the design of approximation algorithms and of limits to obtaining such performance guarantees; this area has been one of the most flourishing areas of discrete mathematics and theoretical computer science. PMID- 9370524 TI - Have sperm densities declined? A reanalysis of global trend data. AB - In 1992 a worldwide decline in sperm density was reported; this was quickly followed by numerous critiques and editorials. Because of the public health importance of this finding, a detailed reanalysis of data from 61 studies was warranted to resolve these issues. Multiple linear regression models (controlling for abstinence time, age, percent proven fertility, specimen collection method, study goal and location) were used to examine regional differences and the interaction between region (United States, Europe, and non-Western countries) and year. Nonlinear models and residual confounding were also examined in these data. Using a linear model (adjusted R2 = 0. 80), means and slopes differed significantly across regions (p = 0. 02). Mean sperm densities were highest in Europe and lowest in non-Western countries. A decline in sperm density was seen in the United States (studies from 1938-1988; slope = -1.50; 95% confidence interval (CI), -1.90--1.10) and Europe (1971-1990; slope = -3.13; CI, -4.96- 1.30), but not in non-Western countries (1978-1989; slope = 1.56; CI, -1.00 4.12). Results from nonlinear models (quadratic and spline) were similar. Thus, further analysis of these studies supports a significant decline in sperm density in the United States and Europe. Confounding and selection bias are unlikely to account for these results. However, some intraregional differences were as large as mean decline in sperm density between 1938 and 1990, and recent reports from Europe and the United States further support large interarea differences in sperm density. Identifying the cause(s) of these regional and temporal differences, whether environmental or other, is clearly warranted. PMID- 9370529 TI - Core geophysics. PMID- 9370537 TI - Foreword PMID- 9370536 TI - The elusive singularity. PMID- 9370538 TI - Introduction to high-speed imaging. PMID- 9370539 TI - Recent and future advances in high-speed imaging. AB - Long acquisition times have long been a major drawback of magnetic resonance imaging (MRI) and have limited its use for all those organ systems with various types of movement, such as respiration, pulsation, and peristalsis. Recent advances in scanner hard- and software, most notably improvements in gradient and radio frequency coil design, in amplifier technology as well as in pulse sequence development, have created new fields of application for MRI. In this review article we give an overview of the development of pulse sequences from the spin echo technique through gradient echo techniques to the fastest imaging technique thus far developed, echo planar imaging (EPI). A variety of clinical applications for the different pulse sequences is included, along with a discussion on the advantages and drawbacks of each technique. The review ends with a discussion of possible future advances in the field of high-speed MR imaging. PMID- 9370541 TI - Clinical utility of contrast-enhanced MR angiography. AB - MR angiography (MRA) is a technique under ongoing discussion. Its non invasiveness and sensitivity to flow irregularities make it an investigational technique which is easy to apply but which does not always lead to comprehensive results. It requires special skill to perform and also experience for correct interpretation of the results. The lengthiness of the procedure combined with certain physical properties tends to limit its use to mostly neurovascular applications. With the introduction of ultrafast MRA in conjunction with peripheral bolus-injection of extracellular contrast media, a new approach to the imaging of such regions as the thoracic and abdominal vasculature not to mention other vascular territories has become possible. In this paper, considerations of bolus and measurement optimization and timing protocols for dedicated indications are presented together with an overview on the experience acquired to date for CE MRA of the carotid artery, mediastinal and pulmonary vessels, abdominal vasculature, and peripheral vessels. The main advantage of ultrafast CE-MRA is that patients are subjected to much more tolerable breath-hold investigations with the result that physiological motion such as peristalsis or major pulsation is minimised. PMID- 9370540 TI - Improvement of post-gadolinium contrast with magnetization transfer. AB - Magnetization transfer (MT) provides post-gadolinium contrast improvement through decreasing the tissue signal. Our study had two aims: to analyse the effect of MT qualitatively and quantitatively in 13 patients, and to analyse in vitro the competition between two relaxation phenomena, dipole-dipole which is characteristic of MT and proton - electron which is characteristic of gadolinium. Contrast between lesion and white matter improved from 20.6 % before MT to 65.1 % after MT, enabling new lesions to be detected in two patients. The improvement was due mainly to the proton - electron effect of gadolinium rather than the dipole relaxation of MT. These results are in agreement with those in the literature. The existence of spontaneous high-signal induced by MT in the absence of gadolinium indicates that it is preferable to perform an MT sequence before and after administration of gadolinium. PMID- 9370542 TI - Interventional MRI: update. AB - Interventional MRI is in its early stages of development. Nevertheless, the design of new interventional MRI scanners that allow maximum direct access to the patient combined with the development of new interventional MRI pulse sequences and localization systems, means that the archetypal operating rooms of the 21st century may well contain dedicated interventional MRI units for combined radiological and surgical procedures. The present article looks at the state of interventional MRI today and looks ahead to what may be forthcoming in the not too-distant future. After briefly discussing the instrumentation necessary for practical interventional MRI, the article will go on to describe a number of different approaches to, and clinical applications for, interventional MRI. The use of MRI in guiding and controlling tumor ablation, aspiration cytology and surgical biopsy of different body parts is described. PMID- 9370543 TI - Advances in high-speed MRI. PMID- 9370544 TI - Functional neuroimaging in the assessment of cerebral ischaemia. AB - Cerebral infarct causes over 170, 000 deaths per year in the United States. Recent developments in neuroimaging are providing an insight into focal cerebral ischaemia, including its pathophysiology and the area of brain at risk. Perfusion weighted magnetic resonance (MR) allows evaluation of the blood supply to the ischaemic area, and diffusion-weighted MR permits assessment of tissue damage. Although both functional imaging techniques require some refinement, it is likely that they will soon become part of the normal clinical routine and allow accurate characterisation of pathology. It is expected that this may eventually lead to the development of new treatments. PMID- 9370545 TI - Functional neuroimaging in the assessment of CNS neoplasms. AB - Assessment of CNS neoplasms has focused traditionally on morphological analysis. Recent developments in MR sequence design now enable functional assessments. T1 weighted, as well as T2(*)-weighted, dynamic, gadolinium-enhanced, imaging can be used for assessment of vascularisation, permeability, and microcirculation of CNS neoplasms. Characterisation of cerebrovascular blood flow is possible using dynamic MR angiography, while neurofunctional imaging enables visualisation of local alterations in neuronal activity in stimulated cortical areas. Diffusion weighted imaging can be used for improved delineation of neoplasms, while chemical shift imaging allows metabolic mapping of lesions and surrounding tissues. Implementation of these techniques can improve characterisation, information for therapy, planning and prognosis in clinical imaging of CNS neoplasms. PMID- 9370546 TI - Dynamic susceptibility contrast magnetic resonance imaging in neuropsychiatry: present utility and future promise. AB - Dynamic susceptibility contrast magnetic resonance imaging (DSC MRI) provides a noninvasive means to create high resolution maps of the regional distribution of cerebral blood volume (CBV). Most DSC MRI studies conducted to date have focused on the evaluation of patients with cerebral neoplasms, ischemia or infarction, and epilepsy. However, preliminary work suggests that DSC MRI may also provide clinically important information for the evaluation of patients with neuropsychiatric disorders, especially dementia and schizophrenia. Additionally, with appropriate modification, DSC MRI may be used to reliably evaluate the effects of pharmacological challenges on cerebral hemodynamics. As pharmacotherapy is an important component in the treatment of a range of psychiatric disorders, the dynamic assessment of changes in cerebral perfusion associated with drug administration may ultimately lead to the development of "brain function tests" for a wide range of disorders. PMID- 9370547 TI - Trends and developments in MRI contrast agent research. AB - The currently prevailing trends in industrial contrast agent research for MRI are discussed. Specific mention is made of contrast agents for liver imaging using both static and delayed procedures, of the potential for blood pool agents and the form such agents may take, and of the ultimate challenge for contrast agent R&D: tissue-targeting in a wider sense to both normal and pathologic tissues. PMID- 9370548 TI - The ProHance story: the making of a novel MRI contrast agent. AB - The four gadolinium chelates currently in clinical use as magnetic resonance imaging (MRI) contrast agents differ in two structural features: linear vs. macrocyclic cores, and ionic vs. nonionic charge types. While all are equivalent in relaxation effectiveness, the nonionic molecules have lower osmolality and viscosity and may be formulated safely at greater concentrations, and delivered confidently at greater doses and as a faster bolus. The macrocyclic molecules are more stable and show less tendency to dissociate free Gd. ProHance was conceived well over a decade ago, based upon a unique structure. It was first marketed in the USA in 1992, and was the first nonionic agent. It remains today still the only commercial MRI agent that is both macrocyclic and nonionic. To date it has been used safely in over a million patients. PMID- 9370549 TI - Contrast enhancement issues in the MR evaluation of the central nervous system. AB - Because of its high intrinsic contrast resolution, magnetic resonance imaging (MRI) has largely replaced computed tomography (CT) in the diagnosis of central nervous system (CNS) diseases, and the use of contrast media in MRI of the CNS has increased progressively, gadolinium chelates being, by far, the most used ones. Our paper will focus on the current indications for contrast-enhanced MR imaging of the CNS and will outline the current role and the future trends in contrast medium (CM) administration in the diagnosis of CNS disease. Gadolinium chelates are now routinely employed in MRI of the brain and spine and have been shown to be relatively safe and well tolerated at standard doses of 0.1 mmol/kg b. w. Although there is general consensus on the usefulness of CM administration in MRI of the CNS, some controversy still persists on the type of CM to be used, on the administration scheme, and on the imaging protocol. The current trend is toward selective employment of CM, the effect of which can be enhanced by Magnetization Transfer (MT) techniques, to increase the sensitivity of the procedure. Double or triple doses of CM can be useful in the detection of small parenchymal lesions with faint enhancement, in functional/dynamic studies of the brain parenchyma and in MR angiography. Gadoteridol (ProHance(R)) closely resembles the features of an optimal CM, because it is non-ionic, has a low osmolality and a low viscosity, and may be particularly efficacious when high doses are required. PMID- 9370550 TI - Contrast enhancement for the abdomen and pelvis. AB - A "quadraphasic" imaging technique is described for imaging malignancies of the abdomen (liver, kidneys and pancreas). With this technique images are acquired during four different phases relative to the administration of contrast agent: pre-contrast (baseline), during the capillary (arterial, pre-sinusoidal) phase, during the portal (sinusoidal) phase, and during the extracellular (delayed) phase. A brief summary of the kinds of malignancy that are best imaged during each of these phases is presented. Finally, comments are presented on the use of gadolinium-based contrast media for imaging tissues of the pelvis. PMID- 9370551 TI - Worldwide clinical safety assessment of gadoteridol injection: an update. AB - Gadoteridol injection is a low molecular weight chelate complex of gadolinium (III) which is useful as a contrast agent for magnetic resonance imaging. A total of 2481 adult and pediatric subjects were studied with gadoteridol at doses from 0.025 to 0.3 mmol/kg in phase I-IIIb clinical trials in Europe and the United States. The study population had a mean age of 49 years, and included 119 patients under 18 years of age and 747 patients over 60 years of age. After 2656 administered injections of gadoteridol a total of 233 adverse events were recorded in 176 exposures, an incidence rate of 6.6 % irrespective of relationship to drug administration. The most frequently reported adverse events were nausea (1.5 %), taste perversion (0.9 %), and headache (0.6 %). All other adverse events occurred with an incidence of 0.5 % or less. This report confirms the excellent safety profile of gadoteridol in healthy subjects and patients with a variety of known or suspected pathologies. PMID- 9370553 TI - Diagnostic imaging in 2001 - a health economics perspective. AB - Factors contributing to the growth and diffusion of new imaging technologies are discussed. The benefits derived from implementing and using new technologies are carefully evaluated against the associated costs to both patients and service providers. The need to invest in early scientific assessment of a new imaging technology in order to prevent wasted acquisition and utilisation later on is highlighted. Such assessment might involve evaluating the ability of the technology to improve diagnosis, positively impact on treatment plans and, above all, improve health. PMID- 9370552 TI - Safety of ProHance in special populations. AB - The safety profile of ProHance in special populations was evaluated by analyzing data extracted from the database of phase I-III studies which included data on 2,656 ProHance injections of which 119 in pediatric patients, 814 in elderly patients and 30 in patients with varying degrees of renal impairment (moderate, severe or end stage requiring hemodialysis). ProHance was administered at doses ranging from 0.1 mmol/kg to 0.3 mmol/kg and was found to be safe in all patient populations irrespective of age and of pre-existing renal impairment. There appeared to be no correlation between incidence of adverse events and dose level in these special populations and the higher dose level of 0.3 mmol/kg could be safely administered also to patients with end stage renal disease requiring hemodialysis, from whom the contrast medium was rapidly and efficiently dialysed. PMID- 9370554 TI - "Controversial issues". Summary of the third session. MRI contrast media: new developments and trends. Symposium. PMID- 9370555 TI - Cost containment and diffusion of MRI: oil and water?. Japanese experience. AB - The total number of MR units available in Japan relative to the population is the highest in the world. The total number of MR units installed in 1996 was 2,663, equivalent to 24 per million population. The average charge per procedure in Japan is only one fifth of that in the United States (USA), approximately US$200 and US$950, respectively, suggesting that economic considerations in Japan may not take the highest priority. Despite the low costs, the utilisation (the number of patients examined each year or per week) of MR units in Japan is only about half that in the USA. As such, an increase in the number of MR units per se does not result in excessive health care costs. PMID- 9370556 TI - Cost containment and diffusion of MRI: oil and water?. The situation in Europe. AB - Investments in diagnostic imaging in European countries range between 2.2 and 5.4 % of gross national product, a figure which, in view of new imaging modalities and increased radiological density, is considered to be wholly inadequate. Despite the fact that radiological examinations contribute more than laboratory tests and other diagnostic modalities to the final clinical diagnosis, and that MR is of increasing clinical relevance, economic constraints mean that the number of new MRI installations in Europe is decreasing relative to the situation elsewhere. The present article discusses the current state of radiological imaging in Europe with particular emphasis on present and expected future trends in MRI. PMID- 9370557 TI - MR equipment acquisition strategies: low-field or high-field scanners. AB - Magnetic resonance (MR) field strength is one of the key aspects to consider when purchasing MR equipment. Other aspects include the gradient system, coil design, computer and pulse sequence availability, purchase cost, local reimbursement policies, and current opinion within the medical community. Our objective here is to evaluate the decision-influencing aspects of the MR market, with a focus on some specific areas such as high resolution studies, examination times, special techniques, instrumentation, open design magnets, costs and reimbursement policies, academic and industrial interests, contrast media, clinical efficacy, and finally, clinicians' preferences. Certainly the advantage of high-field is a higher signal-to-noise ratio and improved resolution. With a high-field unit, higher spatial resolution images and higher temporal resolution images can be obtained. Typical imaging times needed to produce clinically diagnostic images are about 3 times longer at 0.1 T than at 1.0 or 1.5 T. High-field-related advanced techniques, such as functional imaging, spectroscopy and microscopy, may become clinically useful in the near future. As long as there is an unlimited demand for MR examinations, it appears financially profitable to run a high-field system, despite the associated higher costs. However, if demand for MR becomes saturated, low-field systems will cause less financial strain on the reimbursement organisation and service provider. Recent emphasis on cost containment, the development of interventional techniques, the increased use of MR for patients in intensive care and operating suites, the deployment of magnets in office suites, and the development of new magnet configurations, all favour the supplementary use of low-field systems. Hence, MR units of all field strengths have a role in radiology. PMID- 9370558 TI - Indication-related dosing for magnetic resonance contrast media. AB - This presentation reviews the issue of contrast media dosing and imaging protocols for the optimal MR imaging detection and characterization of pathology. The cumulative clinical experience gained in performing contrast-enhanced MR examinations with gadolinium chelates indicates that a dose of 0.1 mmol/kg body weight provides safe and effective enhancement of most CNS pathology. Doses lower than 0.1 mmol/kg have been shown to be inadequate for delineating all but selected types of CNS pathology, such as masses with a high lesion to background ratio on post-contrast images (acoustic neuromas) or lesions located in areas in which the normal tissue very rapidly takes up contrast agent (e. g. microadenomas in the pituitary gland). Recent clinical studies have suggested a role for high dose gadolinium administration (up to 0.3 mmol/kg) for the optimal detection and delineation of cerebral metastases or other small or poorly enhancing lesions. Differences in the histopathologic characteristics (capillary permeability, vascularity, location, size) of specific diseased tissues may require varying doses or even a different contrast agent to be used for optimal imaging results. As new MR contrast agents and new scanning techniques are introduced, the specific diagnostic question posed will likely determine the choice of pulse sequence, contrast agent and dose used. PMID- 9370559 TI - How much contrast is enough?. Dependence of enhancement on field strength and MR pulse sequence. AB - The overwhelming majority of published studies defining the clinical utility of gadolinium administration for neuroimaging have been performed at high field using conventional spin-echo imaging. Concerning the issue of field strength, several investigations have now shown that for a given dose of contrast, enhancement is less apparent at low field than at high field. Concerning the issue of pulse sequence, there is now convincing clinical and experimental evidence that all T1-weighted sequences are not equal in demonstrating contrast enhancement. Specifically, T1-weighted spoiled gradient-echo sequences do not show the same degree of visually apparent contrast enhancement compared to conventional spin-echo sequences. The use of magnetization transfer techniques which demonstrate areas of enhancement unseen on conventional pulse sequences is also addressed. PMID- 9370560 TI - Contrast-enhanced breast MRI: factors affecting sensitivity and specificity. AB - Contrast-enhanced MRI (CE-MRI) of the breast has been investigated for over 10 years. The reports of sensitivity for cancer detection have generally been greater than 90 %. However, estimates of specificity have varied greatly. Differing results are due to differences in study populations, technical methods and criteria for interpretation. Early and marked signal rise, detected using dynamic imaging technique following contrast administration, is the MRI hallmark of cancer. However, some malignant lesions may enhance slowly or minimally, and a variety of benign lesions may enhance rapidly with marked signal intensity. High resolution techniques generally requiring longer acquisition times are more likely to depict the slowly enhancing malignancies at the cost of a decrease in specificity due to lack of temporal resolution. This disadvantage may be offset by the improved visualization of lesion morphology with high resolution images. This report reviews the methods and results of the leading investigators of breast MRI. PMID- 9370562 TI - MRI contrast media - new developments and trends. CTA vs. MRA. AB - Recent developments in the non-invasive techniques of magnetic resonance angiography (MRA) and computerised tomographic angiography (CTA) are challenging conventional catheter angiography. Current indications for both techniques are discussed, such as their ability to diagnose aortic, pulmonary, renal, carotid and peripheral vascular diseases. Both tools provide almost identical clinical results, although each has their own advantages and disadvantages. MRA should be the technique of choice in young patients or those with real impairment since the gadolinium-based contrast agents are non-ionising and do not cause nephrotoxicity. On the other hand, MRA examination times are longer than those typically required for CTA, and therefore MRA is less suited to examinations of acute conditions. PMID- 9370561 TI - Sensitivity of enhanced MRI for the detection of breast cancer: new, multicentric, residual, and recurrent. AB - Magnetic resonance imaging (MRI) of the breast brings the advantages of high resolution cross-sectional imaging to breast cancer diagnosis, treatment and research: improved cancer detection, staging, selection of therapy, evaluation of therapeutic response in vivo, detection of recurrence, and even the development of new therapies. Until now breast cancer treatment and research has been impeded by the limited means of evaluating the breast cancer in vivo: primarily clinical palpation and mammography of the breast tumor. A review of the initial studies shows that with the use of paramagnetic contrast agents, MRI has a sensitivity of 96 % for detecting breast cancers. MRI detects multicentric disease with a sensitivity of 98 %, superior to any other modality. The ability of MRI to detect recurrent local breast cancer in the conservatively treated breast is nearly 100 %. MRI is capable of monitoring tumor response to chemotherapy and actually guiding therapeutic interventions such as interstitial laser photocoagulation. PMID- 9370563 TI - Professional apathy regarding UKCC elections. PMID- 9370564 TI - Controlling the direct supply of genetic tests. PMID- 9370565 TI - Nutrition and diabetes: putting guidelines into practice. AB - Dietary recommendations for the management of diabetes have changed over the past 10 years. There is now a reduced emphasis on the importance of carbohydrate in the diabetic diet. The first move away from carbohydrate restriction came in 1982 when the British Diabetic Association published its 'Dietary recommendations for diabetics for the 1980s'. This document suggested that the diet for people with diabetes should be based on a high intake of complex carbohydrate and fibre, with a restriction of fat intake. This article discusses the impact of these recommendations on different nutrients, and demonstrates, through the use of a case study, how these can be put into practice. PMID- 9370566 TI - Commercial gene testing: the need for professional and public debate. AB - Commercial gene tests are currently available in the UK and the range of tests offered is likely to increase. While knowing their genetic status may bring benefits to individuals and their families, genetic testing also brings its own unique problems. Commercial ventures may do little to resolve these and adequate safeguards are needed to ensure that clients undergoing testing are not disadvantaged. The availability of gene tests can only serve to heighten public awareness of the relevance of genetics to health care, and there is likely to be an increased demand for information and advice from healthcare professionals before, and following, testing. Nurses should be prepared to acquire adequate knowledge to maintain their role as health educators, and to participate in public and professional debate on the issues that commercial testing highlights. PMID- 9370567 TI - Lower limb amputation 2: once the decision to amputate has been made. AB - This is the second of four articles on lower limb amputation. The first article (Vol 6(17): 970-7) discussed the indications for amputation and briefly outlined the treatment options that may be tried before the amputation stage is reached. This second article examines the factors that need to be addressed once the decision to amputate has been made. It stresses the importance of preparing the patient and his/her family both psychologically and physiologically for the operation. The techniques and rationale for selecting the optimum level of amputation are then discussed. Finally, the specific levels of lower limb amputation are outlined. The next article in this series will explore the nurse's role in preparing the patient for an amputation, and the final article will address the issues raised when a patient decides that death is preferable to living as an amputee. PMID- 9370568 TI - Can leaflets assist parents in preparing children for hospital? AB - This article outlines the findings and implications of a small study designed to investigate the perceived usefulness of an information leaflet entitled 'Preparing your child for hospital: a parents' guide'. The study was carried out in an ear, nose and throat unit where children are admitted for elective surgery. A leaflet was developed and field tested before being mailed to a group of parents. An analysis of the data collected demonstrated considerable parental satisfaction with the information contained in the leaflet. The authors believe that similar leaflets should be routinely distributed to families with children awaiting hospital admission. PMID- 9370569 TI - Children's perceptions of asthma: establishing normality. AB - This qualitative research study explores children's perceptions of having asthma. The research methodology utilized a grounded theory approach. The study aimed to identify the beliefs and attitudes held by asthmatic children regarding their illness and to consider how this influences their asthma management. Ten asthmatic children, boys and girls, aged between 9 and 12 years, were interviewed. The transcribed interviews were analysed using the constant comparative method. Analysis revealed four major categories and a core variable identified as 'establishing normality'. These themes influenced each child's appraisal and response to having asthma. The findings show that their concern to establish normality and to be 'normal' does have benefits, but in some circumstances also encourages the acceptance of suboptimal control. PMID- 9370572 TI - The challenges and benefits of job sharing in palliative care education. AB - This article examines the authors' experience of job sharing a post in palliative care education. It discusses the concept of job sharing and examines factors such as power sharing, compatibility and other people's perception of the job sharing role. Effective communication is identified as a key issue. Benefits such as reduced professional isolation, increased job satisfaction and the opportunity to offer the knowledge and skills of two people are highlighted. The authors identify the factors which they consider to be crucial to the success of job sharing. PMID- 9370570 TI - The Pegasus Overture alternating-pressure mattress overlay. AB - Pressure sores affect approximately 10% of the adult population and occur in various hospitals and community settings (Department of Health, 1992). It is therefore essential to adopt a logical approach when selecting the optimum piece of equipment for patients at risk of pressure sore development. Alternating pressure mattresses have been used for many years in both hospitals and community environments to prevent and treat pressure sores. In September 1995, Pegasus Airwave Limited launched a new alternating-pressure mattress overlay, the Overture. It is designed for use with patients who have mobility problems and are at low to medium risk of developing pressure sores or have superficial tissue damage. This article describes the features of the Overture and its suitability for use in different care settings. PMID- 9370571 TI - Clinical risk modification. AB - Claims for compensation in cases of clinical negligence have risen dramatically in recent years. The implementation of the NHS reforms, with greater clarity of roles and responsibilities and the emphasis on devolving decision-making as close to the patient as possible, is meant to affect the entire performance of healthcare delivery. For most senior managers and clinicians, the environment in which they operate has grown increasingly turbulent and complex. Both purchasers and providers of health care want the best and most effective and efficient care. The cost and quality of care are components in determining the value of health care delivered, and both are elements of healthcare risk. To begin to manage these elements of risk, the process of healthcare risk modification can be applied. Healthcare risk modification provides the best service for patients through obtaining a synergy between risk management, quality and the law. PMID- 9370574 TI - Alternative therapies--hoaxes or viable options? PMID- 9370573 TI - Barriers to evidence-based nursing care. PMID- 9370575 TI - The postanesthesia care unit: a high-risk environment for bloodborne and infectious respiratory pathogens. PMID- 9370576 TI - Waste anesthesia gases. WAG. PMID- 9370577 TI - Multiple changes, multiple opportunities in the ambulatory surgery department. AB - As one facility that was restructured and purchased, the Ambulatory Surgery Department moved through changes at a very rapid pace. The waves of change began with preoperative testing requirements and expansion of the nurse's role in accurate and appropriate testing decisions. Cross-training for radiology, pain management, infusion services, and oncology services were also incorporated. As the department became a multi-faceted area of patient care, nursing staff met the challenge of change and grew both educationally and professionally. This article identifies areas of departmental and professional opportunity and outlines the development of protocols to meet each challenge. PMID- 9370578 TI - Pain management: a quality improvement project. AB - Pain management in the PACU is vital to patient care and favorable outcomes. Understanding all aspects of pain management is essential when caring for surgical patients. Most PACUs have quality improvement (QI) and/or risk management projects that involve pain management. This article discusses a QI project on the management of pain and the effect it had on nursing practice. The QI committee developed an improvement program that identified a patient care need and changed practice to improve patient care. The project began with the question "Are we accurately assessing patients' pain, or is the pain assessed only what the nurse perceives?" The QI data collected indicated that 100% of patients were discharged with adequate pain relief. The question was answered by following the recommendations of the Joint Commission on Accreditation of Healthcare Organizations for the QI process, in addition to using a model for linking outcomes to care processes developed by Windle and Houston. PMID- 9370579 TI - Improving telephone follow-up after ambulatory surgery. AB - The number of ambulatory surgery procedures performed annually is steadily increasing. Telephone follow-up of patients after ambulatory surgery remains an important component of care for ambulatory surgery patients. The purpose of this prospective quality improvement project was to obtain a more comprehensive telephone follow-up of ambulatory surgery patients in a large metropolitan medical center. During a 3 month evaluation period, 485 patients (61% of a convenience sample of 798 who had undergone an ambulatory surgical procedure) were interviewed to determine the incidence of side effects and elicit patient satisfaction. Postoperative side effects reported most frequently included pain, bleeding, nausea, dizziness, and fever. A majority of patients reported receiving adequate discharge instructions and excellent nursing care. This quality improvement project initiated by staff nurses resulted in changes in the procedure for documenting postoperative phone assessments from narrative notes to the use of a semistructured form for telephone follow-up after ambulatory surgery. PMID- 9370580 TI - Care of the patient undergoing transurethral resection of the prostate. AB - Transurethral resection of the prostate (TURP) for benign prostatic hypertrophy is a common surgical procedure in the United States. Left untreated, benign prostatic hypertrophy can lead to detrimental consequences such as renal failure from urinary obstruction. Although TURP is a common procedure, it is not without risk. Complications can occur, and the perianesthesia nurse must be familiar with them and their treatment. Complications related to the surgical procedure and the anesthesia technique must be assessed and treated quickly to prevent morbidity and mortality in these patients. The perianesthesia nurse is instrumental in managing and preventing complications associated with transurethral resection of the prostate. PMID- 9370582 TI - Designing research survey design--Part Two. AB - Surveys are essential for discovering the incidence, distribution, and inter relationship of variables within a population. As such, it is important that we are able to critically read published surveys. This manuscript is the second of two dealing with survey research. This manuscript deals with the advantages and disadvantages of different types of surveys and what the reader should be looking for when reading survey research. PMID- 9370581 TI - Risks and outcomes of perioperative pulmonary aspiration. AB - A 95 kg, 34-year-old woman undergoes a laparoscopic tubal ligation. Shortly after endotracheal extubation and during transport to the PACU, she attempts to cough, and gags and vomits. As she is wheeled into the PACU, she is coughing and cyanotic. The anesthesiologist quickly reanesthetizes and reintubates her. Concerned that she may have aspirated the vomitus into her trachea, you suction her endotracheal tube and find thick bilious secretions. How important is pulmonary aspiration? What are the risk factors? When does aspiration occur during the perioperative period? How do you treat pulmonary aspiration? What went wrong here? PMID- 9370583 TI - Practical points in the differential diagnosis of chest pain. PMID- 9370584 TI - The fourth turning. AB - As history has a way of repeating itself, looking at the past can offer some insight into the future. If, as the authors of the discussed book point out, the country is soon facing a crisis, we can prepare for it rather than waiting for it to happen. During the unraveling of an old culture when chaos is the order of the day, the opportunity for participating in the development of a new order is open to anyone willing to invest in the future. PMID- 9370585 TI - The silent disease. PMID- 9370586 TI - Hydrostatic leg ulcers: a new classification. AB - The classification of leg ulcers into standard aetiologies was conducted using a sample of 205 patients referred to the department of dermatology, Malmo University Hospital in Sweden. Patients with venous ulcers formed the largest group (51%). Classification was not possible in 31 patients (approximately 15%) and this formed the second largest group. A comparison of ulcer characteristics between this unclassified group and the venous ulcer group showed that the unclassified ulcers occur in patients with little or no venous disease and display different characteristics from venous ulcers. As a result of these differences, we propose that there should be a further classification of ulcers, known as 'hydrostatic' ulcers. The identification of this type of ulcer has important consequences for future ulcer management as these patients will not require venous surgery or further compression therapy following healing. PMID- 9370587 TI - Protocol for accurate assessment of ABPI in patients with leg ulcers. AB - Ankle brachial pressure index (ABPI) calculations are performed by nurses in the assessment of patients with leg ulceration. The measurement of pressure in one arm alone can result in inaccuracy which may be clinically significant. Two vascular nurse technologists performed ABPI measurements on 250 patients with 487 lower limbs. Community nurses replicated the study on 71 patients, assessing 123 lower limbs. The study shows that 22% of patients in the vascular laboratory and 20% in the community had a difference in brachial pressures of > or = 15 mmHg, indicating the presence of arch vessel or upper limb arterial disease. Furthermore, 6% of patients in the laboratory and 2% in the community demonstrated that the difference in brachial pressures affected the ABPI calculation around the value of 0.8, thus potentially influencing their clinical management. ABPI measurements should be performed, taking both brachial pressures for optimum results. PMID- 9370588 TI - Evaluation of a tool used to assess the management of fungating wounds. AB - This study evaluates the use of the Teler system tool in assessing the effectiveness of dressings used in patients with fungating malignant wounds. The Teler system of clinical evaluation was adapted for the study. This system measures outcomes for the key variables of symptom control, dressing performance and impact of the wound on the patient's daily life by tracing change or lack of change. Data are presented from one patient, and summarised data from 16 additional patients, relating to number of dressing changes, control of exudate and dressing fit. PMID- 9370589 TI - The aetiology and management of plantar callus formation. PMID- 9370590 TI - A tool for assessing perineal trauma. AB - The initial aim of this study was to develop a reliable visual tool to assist in the assessment of the severity of oedema and bruising in perineal trauma, using a categorical scale of 'none', 'mild', 'moderate' and 'severe'. A standardised set of photographs was selected by 10 clinically experienced midwives to represent these categories. The tool was tested in a clinical trial involving 77 women, recording and monitoring changes in the level of oedema and bruising during the first 48 hours following suturing of an episiotomy. The results demonstrated a statistically significant change for both oedema and bruising. However, the less experienced assessors reported some uncertainties in assessing a small proportion of women. A combined method, using this tool with a categorical scoring scale, was used to minimise difficulties in the assessment. Two pairs of midwives, one pair very experienced in assessing perineal trauma and the other less experienced, evaluated the combined method. The results showed a high level of agreement. The standard set of photographs and categorical scoring scale together resulted in a reliable and sensitive assessment tool to evaluate severity of perineal trauma. PMID- 9370591 TI - An educational initiative in pressure area management for nursing home staff. PMID- 9370592 TI - Evidence-based management of patients with leg ulcers. PMID- 9370593 TI - Research-based or idiosyncratic practice in the management of leg ulcers in the community. PMID- 9370594 TI - [Care of dying children and their parents]. PMID- 9370595 TI - [The kangaroo method (skin to skin contact) for premature infants]. PMID- 9370596 TI - [Drainage cradles in Uzbekistan]. PMID- 9370597 TI - [No truth without hope--particularly with sick children]. PMID- 9370598 TI - [Nursing report on the course of a severely brain-damaged former premature infant]. PMID- 9370599 TI - [Nursing anamnesis--determining the emphasis]. PMID- 9370600 TI - [Costs of usual and recommended nutrition of infants and pre-schoolers]. PMID- 9370601 TI - [Consequences of the ambivalence about openness and transparency]. AB - Personnel at the general intensive care unit at the University of Heidelberg Children's Hospital aim for a maximum of openness and transparency for parents regarding everything relevant to their own child. In this context ward nurses were interviewed about diverse aspects of their work. Aside from technical medical activities, nurses regarded the relationship to the parents to be a central point in their work. The recognize that the relationship to the parents influences the relationship to the child and partially even the nursing of the child. Nurses are in favor of openness and transparency in relating to parents, however, reality reveals contradictions. Nurses differentiated attitude and the consequences for physicians, psychologists and parents are discussed. A case example is presented. PMID- 9370602 TI - [Communication structures of a leading team--modern management instruments in nursing]. PMID- 9370603 TI - [Legal questions about dealing with central venous catheters]. PMID- 9370604 TI - [The "Gray Panthers" of pediatric nursing. The professional-political bite has its tradition in the Pediatric Nursing Association. Report on a former meeting in Munich]. PMID- 9370605 TI - [The undiagnosed suffering]. PMID- 9370606 TI - [Treat the foreigner as an individual]. PMID- 9370607 TI - [Outpatient practice nursing in Lima, where health is only for the rich]. PMID- 9370608 TI - [TV series and reality]. PMID- 9370609 TI - [Late fall]. PMID- 9370610 TI - ["Youth without drugs". No!]. PMID- 9370611 TI - [The arts, source of health]. PMID- 9370612 TI - [Abuse of the aged. Adequate support for the family]. PMID- 9370613 TI - [Representation of masculinity. Absent fathers, missing models]. PMID- 9370614 TI - [A new benefit for the handicapped. Traveling in a wheelchair]. PMID- 9370615 TI - [Mobbing, also among health personnel?]. PMID- 9370616 TI - Whose safety in childbirth? PMID- 9370617 TI - The babymilk question. PMID- 9370618 TI - Midwives, midwifery and the Internet. PMID- 9370619 TI - Manoeuvres for the relief of shoulder dystocia. PMID- 9370620 TI - Safe practice or prejudice? PMID- 9370621 TI - Misoprostol: preventing postpartum haemorrhage. AB - Postpartum haemorrhage is an important cause of maternal mortality and morbidity. In the developing world, it is estimated to account for 28% of maternal deaths. Evidence suggests that active management of the third stage of labour using oxytocics, significantly reduces the risk of PPH. Oxytocics are not always used in the developing world, due to storage problems, mode of administration and associated side-effects. Research using misoprostol, a prostaglandin, suggests that it may be effective in the prevention of PPH. It is given orally, does not require refrigeration and has few side-effects. Further research is planned, if misoprostol is found to be an acceptable alternative to other oxytocic agents, then it may be instrumental in reducing world wide deaths from PPH. PMID- 9370622 TI - Culture and condoms: a review of research literature. AB - Research into the use of condoms rarely explains how cultural factors influence beliefs and behaviours. Condoms are researched in functional, rather than cultural terms. Ignorance concerning the mechanisms of conception and contraception remains a fundamental concern, even among comparatively well educated populations. Men's perceived ambivalence to the regular use of condoms, and women's perceived stigma in obtaining and carrying condoms is a limiting factor to the more widespread use of barrier contraception. The etiquette barriers associated with discussing contraceptives, between partners and between couples and health care workers is an issue that extends across cultural boundaries. There is merit in understanding contraception from a cultural start point. This may involve investing more time in orientating to the culture before discussing the contraceptive. PMID- 9370623 TI - The Maternity Alliance. PMID- 9370624 TI - Achieving qualification--a new proposal. PMID- 9370625 TI - Practice-led education and development project: developing styles in clinical supervision. AB - This paper is the second installment which reports a study conducted by the authors following successful application to the Yorkshire Regional Health Authority in response to a call for proposals for studies into practice-led education and development. The aim of the project is to pilot and evaluate an approach to leadership development based upon a conceptual model of reflectivity within a learning organization whilst developing and evaluating a model of supervised practice. PMID- 9370626 TI - Preparation of nurses to meet the needs of an ethnically diverse society: educational implications. AB - In recognizing the multiethnic composition of contemporary society in the UK, this paper considers the implications for nurse education in respect of preparing practitioners who are capable of meeting the needs of an ethnically diverse population. It begins by considering briefly some contextual issues relating to the health needs of ethnic minorities and how they impact upon nursing practice. The literature clearly indicates some of the complexities that nurses face in attempting to deliver care which is responsive to the individual needs of patients in a multicultural context. The question then arises as to how nurse education can most effectively prepare future practitioners. Consideration is given to the curriculum content, methods and approaches that may be utilized together with different teaching and learning strategies. The case is made for the need for nurse educators to also consider the recruitment and support of students from ethnic minority groups, if nursing is to make progress in responding more appropriately to the needs of ethnic minority groups in the UK. PMID- 9370627 TI - Toward building an international consensus in professional values. AB - Although the importance of professional values has been espoused and national codes for nurses exist, there is a lack of systematic study to ascertain the commonalities of values among professional nurses. As part of a larger international study of professional values, nursing students from England and the USA (n = 130) were surveyed to determine congruence of values. The Professional Values Scale (PVS) instrument was used to collect data. Results showed a high degree of congruence among nursing students. The incongruencies found may be related to cultural differences in education and practice. PMID- 9370628 TI - Developing a framework for the future: a qualitative perspective on postgraduate nursing education in Hong Kong. AB - This paper addresses some of the issues related to determining the postgraduate education needs of nurses and the development of a locally appropriate framework for postgraduate nursing education in a country newly embarking on tertiary education for nurses. It reports part of a survey conducted among graduate nurses in Hong Kong, with reference to their expectations for locally prepared and presented higher education that will equip them for expert practice in their chosen specialty. Over 700 nurses participated in the survey, representing almost 50% of the graduate nurse population. The findings reported here provide a qualitative insight into the reasons underlying their preferences, the difficulties they experience in pursuing further education and the reasons why pragmatic rather than preferred choices must be made. It will be argued that these are important considerations in planning for future developments in postgraduate education in Hong Kong. They may also prove useful to countries facing similar developments. PMID- 9370629 TI - Primary health care: from classroom to reality. AB - This paper addresses a model for teaching the theory and practice of primary health care to nursing students at a South African university. The legal background for the inclusion of primary health care in undergraduate programmes is explained, as is the practical solution for clinical placements in a rural setting. An explanation is also provided for the development of clinical resources within the clinical field, and the paper concludes with a summary of the students' experience, thus showing how positive attitudes towards primary health care were fostered. PMID- 9370630 TI - Reflection in groups: contextual and theoretical considerations within nurse education and practice. AB - The action learning group (ALG) has been described as a mechanism to facilitate reflective practice. As a member of such groups, I contend that although a potentially ideal setting for learning, the group may evoke repressed anxiety and distress caused by self-awareness and contact with patients. This, if not contained, will hinder the process of learning from and through experience. More rigorous attempts by those conducting such groups may be required, to maintain the boundary and thus the safety of the group, and to obtain supervision, in order to deal more effectively with problems arising. PMID- 9370631 TI - Teaching pharmacology by case study. AB - This paper describes why case studies deserve a place in the centre of the bioscience curriculum, and how they have been used as a vehicle to improve care and save lives. A knowledge of drugs, their side-effects and interactions is becoming increasingly important to nurses. One powerful way to convey this information is the case study, which, despite its limitations, has the potential to endow difficult topics in therapeutics with the power of the narrative. The author suggests that case study projects encourage students to forge theory practice links, related to their own specialist areas. When shared with their colleagues, these encourage the class by illustrating 'bioscience in action' and endowing the subject with the 'reality factor'. They also provide rich qualitative data for evaluating and delineating the curriculum. These case studies demonstrate the value of evidence-based practice; although case data is part of the evidence, it can never substitute for evidence-based practice. This paper builds on the findings of the author's PhD in postregistration nurse education; the examples described here are typical of 151 such cases in the research project. PMID- 9370632 TI - The continuing professional education needs of midwives. AB - The philosophy behind Post Registration Education and Practice (PREP) dictates that continuing professional education (CPE) must be tailored to the needs of the individual and relevant to the practice environment. The study is set within the context of PREP and other changes that are currently affecting midwives and midwifery educational establishments. This study sought to explore the CPE needs of midwives. The main objective of the study was to seek information on a number of issues that would assist with the planning and implementation of continuing education programmes to meet the needs of midwives. The study takes the form of a descriptive survey. Questionnaires were sent to 696 midwives employed by 7 National Health Service Trusts in the South-West of England. A 45% response rate was achieved. Seven midwife managers were also interviewed to gain insight into their perspectives of CPE and to enhance the findings from the questionnaire. Results show that midwives use a variety of strategies to identify their CPE needs. One of the more significant seems to be through interaction with colleagues. 'Professional issues' and 'management topics' were the categories identified by both midwives and managers alike to be the greatest need. There is a demand for part-time and distance learning. The format and timings that would ensure that midwives find it easy to attend CPE events were identified. Findings illustrate how midwifery managers and educationalists can facilitate midwives with their CPE and career development. PMID- 9370633 TI - Compiling a placement audit tool: a case study of one college's use of the QualCube model in developing an audit tool for student placement areas. AB - Nursing students, as users of college services, can rightly expect satisfaction and even continuous improvement in their clinical experience, which is one of the cornerstones of nurse education. The North Yorkshire College of Health Studies has developed and used a multidisciplinary placement audit tool based on QualCube, a framework for standard setting, auditing and improving quality developed by Nicklin and Lankshear (in Nicklin & Kenworthy 1995 p 18). In order to facilitate a thorough audit of placement areas, a working group devised the tool based on the relevant areas of intersection of the three planes of the cube and then set written standards and specified performance criteria. This article describes the application of the QualCube framework, the design and description of the tool and feedback on its usage. The exciting and useful difference in the tool is its final page, the action plan, which is designed to realistically encourage continuous improvement in each placement area. PMID- 9370635 TI - The spiritual dimension: why the absence within nursing curricula? AB - This article explores the complex barriers which may have prevented the formal integration of the spiritual dimension within programmes of nurse education in the UK. These barriers have been termed intrinsic (arising from within the educational institutions themselves) and extrinsic (reflecting society's and individuals' values, beliefs and cultural norms). It is argued that these barriers have slowed down curriculum innovation and change, preventing the spiritual dimension from receiving due recognition within programmes of nurse education. PMID- 9370634 TI - The role of the external examiner in the assessment of clinical practice. AB - In the first part of this paper we give a brief overview of the development of the different types of clinical assessment used in the UK. Some general problems related to the assessment of clinical practice are outlined. The second part of the paper focuses on the role of the external examiner in the clinical assessment of students. We outline some of the major problems we encountered as internal and external examiners on the same university-based course in which 'I-day' practical assessments were undertaken. We emphasize the particular problems of externally assessing the clinical practice component of the course in this manner and conclude that the continuous assessment model, while not without its own problems, is potentially a more effective approach to student assessment. PMID- 9370636 TI - Issues in the sphere of elder abuse and neglect: the role of education. AB - In recent years, there has been an increased emphasis on violence and abuse within society. It therefore seems appropriate to consider the role of education in promoting a greater understanding of the linked phenomena of elder abuse and neglect, and of the quality of life of older people. The rationale behind the educational process covering the area of elder abuse and neglect has not, until now, been discussed in any structured or open way. Education concerning these social problems has tended to develop in an ad hoc manner, with numerous organizations, professionals and academics developing their own ideas about what might be considered to be an appropriate curriculum. This paper aims to address some of the fundamental questions which need to be explored, including: who is to be educated; what knowledge is to be taught; and how is it to be taught? PMID- 9370637 TI - Caring for communities. PMID- 9370638 TI - Taking time for ourselves. PMID- 9370639 TI - Nursing pay rates continue to widen. PMID- 9370640 TI - 'To sleep perchance to dream'. PMID- 9370641 TI - Giving a framework to nursing education? PMID- 9370642 TI - The axe falls on Stratford Hospital. PMID- 9370643 TI - Managing pain without drugs. PMID- 9370644 TI - Treating leg ulcers. PMID- 9370645 TI - Facing the challenges of emergency nursing. PMID- 9370646 TI - Working harder, earning less and dropping out. PMID- 9370647 TI - Sea change. PMID- 9370648 TI - Safe house. PMID- 9370649 TI - Time for broader leadership... PMID- 9370650 TI - Getting needled. PMID- 9370651 TI - Nurse 97 awards--Bailliere Tindall. Anticipating anxiety. Interview by Charlotte Alderman. PMID- 9370653 TI - Nursing with a human face. PMID- 9370652 TI - The shape of things to come. PMID- 9370654 TI - Clinical trials: what cancer patients need to know. The British Association of Cancer United Patients (BACUP). AB - In this report we highlight guidance issued by BACUP, the British Association of Cancer United Patients, on what cancer patients need to know about clinical trials. The information is to help nurses, GPs and other health professionals give patients the information they need to make an informed decision about participating in a trial. PMID- 9370655 TI - Making sense of clinical guidelines. AB - In a companion article to their paper on clinical effectiveness (McClarey and Duff 1997), the authors discuss the issues surrounding clinical guidelines. How they are developed and how they can be adapted to local practice are described to allow practitioners to base their practice on the most up-to-date research evidence. PMID- 9370656 TI - Multidisciplinary collaborative care planning. AB - Over many years, healthcare professionals have strived to improve the quality of patient care. The idea that collaborative care might achieve further improvements is relatively new but is a natural consequence of the Patient's Charter (1992) and other national standards. This article describes how multidisciplinary care planning was introduced in the stroke rehabilitation unit at Clatterbridge Hospital, Wirral Hospital NHS Trust. PMID- 9370657 TI - Hospitalising children: a review of the effects. AB - In this literature review, the author examines the effects of hospitalisation on children. In particular, the case for having a parent present throughout the admission is discussed, along with evidence for encouraging parents to become more involved in actual care. PMID- 9370661 TI - Spirit level. PMID- 9370659 TI - Alternative sources of funding for the NHS. PMID- 9370658 TI - Influenza vaccination. AB - The availability of influenza vaccines brings relief to high-risk categories. For trained and competent nurses this means carrying out an audit of high-risk people and ordering sufficient doses in the spring and summer, and then administering vaccines to this group in the autumn. PMID- 9370660 TI - Cutting health corners. PMID- 9370662 TI - Vocal discord. PMID- 9370663 TI - Time for action from the top. PMID- 9370664 TI - In the know. PMID- 9370665 TI - Bitter pill. PMID- 9370666 TI - Climbing the clinical ladder. PMID- 9370667 TI - Leading the way. PMID- 9370669 TI - Charter mark. PMID- 9370668 TI - As others see us. PMID- 9370670 TI - Institute of psychiatry: work in progress. PMID- 9370671 TI - Deliberate self-harm: developing clinical guidelines. AB - Nurses in an acute admissions psychiatric ward are using reflective practice to develop clinical guidelines for the management of patients who deliberately self harm. In this article, they describe the cyclical learning processes and reflective techniques involved. PMID- 9370672 TI - Snoezelen: benefits for nursing older clients. AB - In this article, the authors examine the possible benefits of Snoezelen for older clients. The authors suggest that nurses can be instrumental in developing and creating innovative therapeutic environments for this vulnerable client group. PMID- 9370673 TI - Retaining and recruiting peri-operative nursing staff. PMID- 9370674 TI - Clarifying accountability in operating theatre practice. PMID- 9370675 TI - Quality in theatre care: a critical analysis. AB - It is difficult to apply a universal definition to 'quality' and what constitutes 'quality' in nursing practice. This article examines quality care in operating theatres by reflecting on two critical incidents. The incidents are then analysed to elicit quality issues arising from them. PMID- 9370676 TI - An introduction to radiotherapy. PMID- 9370677 TI - Postscripts from the edge. PMID- 9370678 TI - Modern dance with death. PMID- 9370679 TI - Child care: the missing link. PMID- 9370680 TI - Working the family-friendly shift. PMID- 9370681 TI - Underwhelming responses. PMID- 9370682 TI - Nutrition and cancer. PMID- 9370683 TI - Clear passage to A&E. PMID- 9370684 TI - View from the floor. PMID- 9370686 TI - Handing back the reins. PMID- 9370685 TI - Mad to work here.... PMID- 9370687 TI - Citizen Smith. PMID- 9370688 TI - Practical procedures for nurses. 3.1. Assessing pulse--1. PMID- 9370689 TI - Phoenix arising. PMID- 9370690 TI - Questions of care. AB - The care Peter Keene's mother received before her death was seen by her family as inadequate. As a result, he wrote a review to help the trust involved learn from the experience and improve services. He has had an uphill struggle, as he tells Adam Legge. PMID- 9370692 TI - Structural barriers to pain control. AB - This fifth article in our series of six articles on the barriers to effective pain management considers how organisational influences can have an impact on the effectiveness of care. Routine, procedure and a lack of flexibility can all inhibit the effectiveness of pain control. This article examines the ways in which nurses can influence practice to make it more responsive to patients' needs. PMID- 9370691 TI - Who are we listening to? PMID- 9370693 TI - Specialist nurse support for clients with blood disorders. PMID- 9370694 TI - Invisible carers. AB - Many people with learning disabilities are finding themselves in caring roles. This article considers these roles and argues that the needs of this group of carers are largely unrecognised. It is written from the author's personal observation and includes two case histories of clients in this situation. PMID- 9370695 TI - Primary care scheme aims for partnership in practice. PMID- 9370697 TI - Mental health education: where to now? PMID- 9370696 TI - Genetic screening: risk factors for breast cancer. AB - The field of cancer genetics is rapidly changing. Demand for information on genetic testing is increasing and persistent patient pressure is likely to result in increased NHS resource allocation. Cancer genetics clinics must change from small ad hoc research clinics to large throughput, patient-centred specialist services run jointly by doctors and clinical nurse specialists expert in cancer genetics and cancer medicine. We describe the development of a regional breast cancer genetics service in East Anglia based on the three-tier cancer care model outlined in the Calman report. PMID- 9370698 TI - Theatre of operations. PMID- 9370699 TI - An NHS winter crisis. PMID- 9370700 TI - A severe facial disfigurement that is difficult to live with. Interview by Esther Leach. PMID- 9370701 TI - Leading players. PMID- 9370703 TI - In search of United States. PMID- 9370702 TI - Nursing education must take telephonic communication into account. PMID- 9370704 TI - All in a day's work.... PMID- 9370705 TI - Phantoms of the hospital. PMID- 9370707 TI - High priority. PMID- 9370706 TI - Why must people have vegetables as go-betweens? PMID- 9370708 TI - Positive thinking. PMID- 9370710 TI - Face values. PMID- 9370709 TI - Practical procedures for nurses. 3.2. PMID- 9370711 TI - The way to take charge. PMID- 9370712 TI - A one-woman crusade. Interview by David Gough. PMID- 9370713 TI - Fellow travellers. PMID- 9370714 TI - How to improve pain management practices. AB - This is the final article in a six-part series that has highlighted how a range of factors can affect patients' experience of pain. The series closes with a consideration of how evaluation of pain management can help, raise awareness of such issues and lead to improvement in the quality of care. PMID- 9370715 TI - Investing in breast-feeding. PMID- 9370716 TI - The immune system, Part 1: Anaphylaxis. PMID- 9370717 TI - [Head outside--feet inside. How do patients from other cultures experience the German health care system?]. AB - More migrants in a country mean also more patients from other cultures. Therefore, it is possible that cultural differences or institutional conditions become the origin of conflicts between patients and nursing personnel. Transcultural studies have mainly investigated problems of German nurses with foreign patients. The aim of the present study is to get to know the patients' own views as experts in their situation: "What are the experiences of migrants with the German Health Care System, especially with hospital nursing care?" The results of the study point out that the main sources of conflicts in hospital are located in institutional conditions rather than in cultural differences of patients. PMID- 9370718 TI - [What does mouth care mean to cancer patients?]. AB - The article describes an analysis of literature concerning the knowledge about mouth care with oncology patients. The still used empirical knowledge in assessing patient needs is compared with the use of assessment tools based on nursing science. The use of traditional mouth care products is discussed too. PMID- 9370720 TI - [A nursing intervention study in interdisciplinary cooperation: challenges and problem solving strategies]. AB - Doing a nursing intervention study in two hospitals in collaboration with physicians challenged all participating parties. The course of the study was influenced and partially changed by unforeseen problems. This article presents organizational perspectives on carrying through an intervention study while daily patient care is taking place and discusses specific issues of collaborating with physicians and nurses. Problem solving strategies and consequences from experiences with this study are presented. PMID- 9370719 TI - [Theories of nursing professionals about the elderly]. AB - Our study emphasizes the implicit theories of nursing professionals about the elderly and their influence on nursing behavior styles. According to our central hypothesis we expected a correlation between the differentiation of attitudes towards the elderly and the quality of nursing interventions. By means of a new methodological approach based on Forgas' theory of "social episodes" we investigated attitudes towards the elderly and behavior intentions in specific nursing situations. The sample consists of 133 professionals working in nursing homes for the elderly or in home care services. In a first step the structure of attitudes towards the elderly was examined by employing multivariate techniques, e.g. factor analysis and multidimensional scaling. Three aspects of older patients' competence constitute the images which influence nursing personnel's interactions with the elderly. In the next step a significant correlation between the complexity of attitudes towards the elderly and the quality of nursing behavior could be demonstrated. In general, the findings in our sample support personalized rather than stereotyped perceptions of the elderly. In particular such qualities will be stressed by nursing professionals which facilitate or disturb the nursing process. PMID- 9370721 TI - [Importance of qualitative research for nursing and nursing science]. AB - Qualitative research has an important place in nursing science and is becoming increasingly recognized. Qualitative research in nursing mainly deals with the lived experiences of patients and nurses. In the field of chronic illness, qualitative research has brought to the open some of the processes chronically ill patients undergo and what it means living with chronic illness. In addition, new insights were gained about the processes involved in receiving and in giving care. Qualitative research about chronic illness provided nurses with understanding of the lived experience of patients. This understanding is essential for good nursing care. However, qualitative research is not the only method and for some aspects of nursing not the adequate one. Qualitative and quantitative research are complementary. PMID- 9370722 TI - [BALINT--seminars in nursing education]. AB - The essay illustrates the importance of the BALINT-concept for nursing studies. It is already possible to practically experience and consider the psychodynamic aspects of the relationship between patient and nurse during the study period. The concept is particularly suited to developing a psychosomatic approach and a "basic therapeutic attitude" in nursing. The concept can, like supervision, contribute to the "Mental hygiene" of the staff, as well as control the quality of care in nursing. A specific method of the BALINT-seminar, the author named this the "Three-phases-Technique", and its benefits, is illustrated through the case study of a session. The psychoanalytical terminology used will be explained in footnotes. PMID- 9370723 TI - [Comparison of expectations and competencies of USA and German nursing students]. AB - This study is concerned with the impact of job expectations and job competence in the development of burnout. In an intercultural and longitudinal comparison expectations of job competence of US and German nursing students are investigated by means of half-standardized interviews at the end of their training. First results indicate that American nursing students regard themselves as better prepared for job reality with respect to job competence and theoretical training than German nursing students. On the other hand, they report distinct deficits of their practical training. These results are discussed against the background of the different training courses in the USA and in Germany. Prognoses for different courses of burnout processes are given which have to be tested in future investigations of the longitudinal study. PMID- 9370724 TI - [The Augsburg Central Hospital is 15 years old. Employers-taxpayers-workers: nursing is recognizing their value]. PMID- 9370725 TI - [The Federal Institute for Vocational Training looks back. Geriatric nursing--a profession for a limited time]. PMID- 9370726 TI - [Dealing with computers is not as hard as it appears]. PMID- 9370727 TI - [Improvements in efficiency and organization in the operating room and in anesthesia. Consideration from the viewpoint of nursing control and of nursing are complementing each other]. PMID- 9370728 TI - [Quality assurance in nursing. When does quality assurance make sense?]. PMID- 9370729 TI - [Nursing insurance--a link in the social network. Where are the points of contact with other social efforts?]. PMID- 9370730 TI - [Documentation system in a half-closed pediatric and adolescent ward. A whole team is enjoying the advantages]. PMID- 9370731 TI - [Approval of housing and restraining of the elderly: small distance between the prohibited and the permitted]. PMID- 9370732 TI - [Oncologic nursing--touching, moving, accompanying]. PMID- 9370733 TI - [What is epistemiology? The rapport between epistemiology and science]. PMID- 9370734 TI - [A representation of science ... an obstacle to doing science]. PMID- 9370735 TI - [Science and social sciences]. PMID- 9370736 TI - [The construction of the object of research in the scientific method]. PMID- 9370737 TI - [The question of research]. PMID- 9370738 TI - [Resolution of problems]. PMID- 9370739 TI - [The notion of variability in the experimental cadre]. PMID- 9370740 TI - [Qualitative research ... without difficulty and without regrets]. PMID- 9370741 TI - [Methodology of qualitative research in nursing care]. PMID- 9370742 TI - [Elaboration of qualitative data in human sciences]. PMID- 9370743 TI - [Case studies in research]. PMID- 9370744 TI - [From the scientific observation to the scientism of observation]. PMID- 9370745 TI - [Documentary analysis or valorization of documents]. PMID- 9370746 TI - [Analysis of contents]. PMID- 9370747 TI - [Quality in nursing care: preambles to methods]. PMID- 9370748 TI - [Quality of life]. PMID- 9370749 TI - [Evaluation of care: taking into account the patients' quality of life and relational elements]. AB - This paper offers a new perspective concerning care evaluation. Patients' quality of life is measured as well as relational and subjective parameters. A questionnaire "SQLP" ("subjective quality of life profile") has been constructed and validated on several thousands subjects. The results obtained have several points of interest. First the questionnaire allows us to describe various populations and their needs; it also allows to track the effects of different treatments and compare them. Finally it also allows to understand some of the treatments' mechanisms of action. The therapeutic relationship has been extensively studied in psychotherapy research. It may be usefull in other therapeutic settings. Various examples are given. A particular attention has been given to the evaluation of the patient/care-giver agreement. PMID- 9370751 TI - [Transformations in the world of work and of health care. Preliminary reflexions]. AB - In this work, I make some preliminary reflections about the transformations in the world of work and health. For this purpose, I start this study discussing essential dimensions of the work like the central category to analyse the society based on the Marxist conception. Following, I investigate transformations in the world of work and the specificity of health to the related reflection about care and the organization of health workers. PMID- 9370750 TI - [Islets of interdisciplinary rationality]. PMID- 9370752 TI - [Relationship between university and health services. Building work situations]. AB - The present study aims at reporting the experience of construction of an interinstitutional relationship: university and health services, pointing out the possibilities and difficulties of the process. PMID- 9370753 TI - [Gender and the working woman in Peru]. AB - This study identifies the peruvian women's labor conditions and its social and historical determinants due to social class, race and gender differences that influence women subordination in social structure. Bibliographic review shows that the peruvian working woman situation experienced great and deep changes in time, as a result of ideological and cultural patriarchal patterns that culminated in the current capitalist society. PMID- 9370754 TI - [The exercise of nursing in its bioethical dimension]. AB - In the present study we approached Bioethics, an area that has been targeted for discussion and reflection within the scope of biological and health sciences, in order to rethink human conduct towards moral values in the current context of great technological and scientific development. We started a discussion about the exercise of nursing in its bioethical dimension, analyzing how such exercise has been occurring at the level of the ethics of principles, which is based on beneficence, autonomy and justice. In this respect, in their relations with patients, the members of the nursing team have adopted a posture based on beneficence linked to the subordination of their practice to the medical act. On the other hand, close contact with patients enables the nursing team to form ties that confer a certain power, which can be used to lead patients to exercise the ir autonomy. PMID- 9370755 TI - [The leadership style exercised by nurses in surgical wards focuses on situational leadership]. AB - The present study was oriented to the leadership theme focussing nurses inside surgical ward unities. As a theoretical reference, the authors used the Situational Leadership Model proposed by Hersey and Blanchard. This study aimed at analysing the correspondence between the opinions of nurses and auxiliary personnel about the leadership style exerted by nurses in the surgical ward unit regarding the six categories of the assistance activity that were studied. Authors noticed that nurses, from the two studied hospitals, adopted the directive leadership styles (E2/selling or E1/telling) with the auxiliary personnel. PMID- 9370756 TI - [Utilization of nursing diagnosis according to Nanda's classification for the systematization of nursing care in breast feeding]. AB - The present study aimed at describing the reformulated instrument used in the puerperal woman nursing consultation based on the identified diagnoses classification according to the Taxonomy-I reviewed by NANDA, and the identification of the most frequent nursing diagnoses concerning maternal breastfeeding, based on the reformulated instrument. The diagnoses found as being over 50% were: knowledge deficit (100%); sleep pattern disturbance (75%), altered sexuality patterns (75%), ineffective breastfeeding (66.6%) and impaired physical mobility (66.6%). PMID- 9370757 TI - [Fruits of technology--must we feed an aged patient at all costs?]. AB - The purpose of this article is to analyze questions on a complex ethic, medical and caring dilemma about reasons to continue or suspend compelled alimentation in really old patients carrying progressive acute dementia. Traditionally, the principle of life holiness supports the idea that life should be extended at all costs and the decision to continue feeding the patients is not questioned. However, revolutionary ideas are arising about attitudes, concepts and value of treatment, conducting an urgent need to discuss this problem deeply. Until when should we compel demented patients to eat, as they do not accept food and have to be fed through a catheter or intraveined alimentation, tying back their hands or using other measures? This discussion occurred in a geriatric institution at Israel, when a doctor's order was not accepted by nurses, as they had a different way of seeing the problem. A national conference on this theme was organized with the attendance of doctors, nurses, social workers and psychologists. PMID- 9370758 TI - [Life style and risk factors in patients with a first episode of acute myocardial infarct]. AB - The prevention of acute myocardial infarction (AMI) has been related to the identification and control of risk factors (RF) present in the life style of the individuals. The aim of this study was to know the profile of patients with a first episode of AMI and to identify RF for this disease. Seventy eight in patients from the Coronary Care Unity of a University Hospital were interviewed. The results showed that the life style of the studied group includes habits that collaborate to coronary artery disease maintenance or progress. These results will help to elaborate an educational program aiming to prevent reinfarction and to promote health. PMID- 9370759 TI - [Educational program in universal precaution measures: a methodological approach]. AB - An updating program on measures of universal precautions (M.U.P.) was developed at the Center of Whole Care of Woman's Health (Centro de Atencao Integral a Saude da Mulher-CAISM). These measures and the procedures in the case of work accident were published in a booklet. First, servants should be aware of the matter of stress and its influence on the quality of life. Then, updating was carried through encouraging the reflection on the consequences of the non-adoption of M.U.P. The answers to 286 pre-tests and 242 post-tests were analyzed and the results showed a significantly higher index of correct answers (p < 0.01), mainly regarding the appropriate use of glove. PMID- 9370760 TI - [Social violence: references from a public health debate]. AB - This article is a part of a research developed by the author. Its aims at analysing aspects of social violence in order to support an approach to this problem in the field of public health. Therefore a theoretical discussion is presented. Finally, the author concludes that the interdisciplinary view and the intersectional actions are necessary for public health aiming at efficiently dealing with the complexity of social violence. PMID- 9370761 TI - [Phenomenology as a methodologic reference: sharing the experience of women who search for the prevention of cervical cancer]. AB - The article has the purpose to bring out the experience of having phenomenology as a methodological reference and Martin Heidegger's philosophical thinking expressed in the book entitled ?Being and Time, used by nursing in order to understanding women who search for the prevention of cervical cancer as well as to analyse teh programs offered to women. PMID- 9370762 TI - [An approach to the phenomenological interview]. AB - The purpose of this study is to describe my experiences about the phenomenological interview. It was developed in four moments, in order to adequate physical environment aspects, strategies of approaching the interviewers, the orientation question and the techniques to obtain the statements. The focus on researcher-subject/researched-subject has indicated adjustments in the utilization of the techniques and reoriented my person and professional development. PMID- 9370763 TI - ["As if I had won the lottery": the meaning of voice rehabilitation in a laryngectomized patient]. AB - This is a case study of a laryngectomized patient with the objective of "describing the meaning of voice rehabilitation". Data analysis was based on the search for categories of meaning. The central theme that emerged from the present study was "As if I had won in the lottery". With these words the patient revealed the complexity of this process. PMID- 9370764 TI - [Teaching nursing communication: a challenge]. AB - The use of video has been described in the literature as favourable to changes in behaviours during communication. This study aimed at verifying the effect of a training programme in the use of categories of confirmation and discordance during the interaction (oral communication) between students and patients. The results evidenced the predominance of confirmation categories in interactions: there were no significant changes in the interaction profile before and after training. Authors concluded that the teaching of communication abilities has to be done during the undergraduate course and not only in one course or period. PMID- 9370766 TI - [Communication between the patient care team and patients with hypertension]. AB - This study aims to analyse data on hypertensive individuals and their concern about the disease as well as to verify the communication process that took place between the individuals and the health staff working with them. Sixty-six individuals were interviewed and we obtained 73 statements. The majority of them (69 narratives) expressed correlation to high blood pressure concepts even though in a poorly elaborated form. Although 95% of the patients referred to the illness, it does not mean that the orientations were understood. Nurses are expected to perform an important role in the multiprofessional team, identifying possible obstacles to the process of communication in order to enable the clients' comprehension and their self care. PMID- 9370765 TI - [Teaching perioperative nursing: a comparative study of audiovisual (video) oral resources]. AB - The aim of this study was to compare information on perioperative Nursing regarding audiovisual (video) and oral resources. 104 patients were registered as subjects and divided in two groups, 54 of them in the oral group and 50 in the video group. Authors concluded that the groups were homogeneous and that there was no significant difference between the two resources used. Independent from the resource used, the responses were qualitatively better. However, regarding perioperative informations, authors spent 10 minutes using the video while oral information lasted 45 minutes. The video unabled verbalization that is characterized by the exposition of methods and reduces the time spent with information. PMID- 9370767 TI - [Blood pressure measurement in pregnancy]. AB - This study deals with the review of the literature regarding the indirect blood pressure measurement in normal pregnant women. It shows the changes that happened with the blood pressure due to pregnancy. Polemical aspects in the procedure of blood pressure measurement are discussed; for example, which one of the Korotkoff phases (4 or 5) that better represent the diastolic blood pressure and the use of Ambulatory Blood Pressure Monitoring in pregnancy. The recommendations from different societies are emphasized (American Heart Association, British Hypertension Society, Australasian Society, National High Blood Pressure Education Program and World Health Organization). PMID- 9370768 TI - [Health education: what it can be, but it is not]. AB - Based on his knowledge and experience, the author evaluates the concept and view of the medicine, health and education practices as well as the citizen's role. Then, the author aims at inquiring and interpreting the causes of the inefficiency of the health system and its changes due to scientific and technological improvement. PMID- 9370769 TI - [Computerized nursing prescriptions as an instrument of communication between multidisciplinary and nursing teams: report of an experience]. AB - This paper presents the computerized nursing prescription as a communication instrument able to promote changes in nursing multiprofessional and intra-team relationships and professional nursing "savoir-faire" socialization. It can become a strategy of reapproximation of nurses and patients/clients, through problems assessment and priorization, elaboration and selection of protocols that will be part of nursing prescription, assuring to patients a planned and adequated care, conducting to modifications in the practice, with repercussions in the forms of managing care and also in the care provided to patients/clients. PMID- 9370770 TI - [Educational communication between nurses and students about sexual health promotion]. AB - As school has been a crucial space for the development of knowledge and abilities in order to assure changes of behavior and considering the lack of reports about sexuality and STD/AIDS to the students, the present study aims to search scholars from three classes of high school, from a town surrounding the city of Ribeirao Preto-Sao Paulo. Authors identified students' problems by carrying out and assessing joint educative actions on the problems that have been found. Results have showed that these students relate AIDS to fatality and temerity and perhaps they are influenced by the message issued at the first decade of the history of this disease while now, the tendency is to work with up to date knowledge and abilities. They form an opinion about AIDS as a sex and preventible disease. A it however, authors detected misinformation in another basic aspects. Therefore, we suggest nurses to work hard with this question. PMID- 9370771 TI - [What nurses say about observation]. AB - The purpose of this study was to characterize what faculty and clinical nurses understand about Observation at their professional activities. Eleven nurses were interviewed, and the data were joined in categories in order to be analyzed. It was possible to realize that they regard it with extreme importance at their professional activities, as an essential instrument of nursing care administration, assessment, planning interventions and evaluating results. PMID- 9370772 TI - [Promoting health through the formation of human resources: the experience of the University of Sao Paulo at Ribeirao Preto College of Nursing--WHO Collaborating Center for Nursing Research Development]. PMID- 9370773 TI - [Are there masters in the art of living?]. PMID- 9370774 TI - [Friendly respect in the nursing relationship]. PMID- 9370775 TI - [Patient's rights. A quiet and beneficial revolution]. PMID- 9370776 TI - [Stress and burnout in emergency. Stress in the nurses of the emergency service of the Funchal Hospital Center]. PMID- 9370777 TI - [Love in the origin of the therapeutic relationship]. PMID- 9370778 TI - [To be born, to live and to die with lead]. PMID- 9370779 TI - [Relaxation techniques for surgical patients]. PMID- 9370780 TI - [The diabetes mellitus regimen]. PMID- 9370781 TI - [Ethics under pressure]. PMID- 9370783 TI - [ICN: president of the world's nurses. Interview by Grethe Kjaergaard and Charlotte Frendved Hansen]. PMID- 9370782 TI - [ICN: the struggle to be included]. PMID- 9370784 TI - [ICN: directors want more feedback. Interview by Grethe Kjaergaard and Charlotte Frendved Hansen]. PMID- 9370785 TI - [ICN: the Danish are visible]. PMID- 9370786 TI - [ICN: solidarity in research]. PMID- 9370787 TI - [ICN: stronger than ever. Interview by Grethe Kjaergaard and Charlotte Frendved Hansen]. PMID- 9370788 TI - [ICN: with various backgrounds]. PMID- 9370789 TI - [ICN: to Denmark in 4 years. Interview by Grethe Kjaergaard and Charlotte Frendved Hansen]. PMID- 9370790 TI - [Danish Nursing Council/District Board of Directors' election. It concerns influence. Interview by Soren Palsbo]. PMID- 9370791 TI - [Danish Nursing Council/District Board of Directors' election. The last little push. Interview by Soren Palsbo]. PMID- 9370792 TI - [Adverse Effects Tribunal--convulsions due to treatment with selective serotonin uptake inhibitors]. PMID- 9370793 TI - [Crucial support]. PMID- 9370794 TI - [Back injuries--remedies are no guarantee]. PMID- 9370795 TI - [Back injuries--focus on attitude. Interview by Claus Leick]. PMID- 9370796 TI - [Back injuries--support in handling stress]. PMID- 9370797 TI - [Mentally handicapped--handicapped sex is taboo sex]. PMID- 9370798 TI - [Mentally handicapped--what do you do?]. PMID- 9370799 TI - [India--women's life is a struggle]. PMID- 9370800 TI - [The Third World--microcredit against poverty]. PMID- 9370801 TI - [Nursing studies--an introductory week provides a better study environment]. PMID- 9370802 TI - [Practice report: a bear story]. PMID- 9370803 TI - [Hygiene nurse--specialist in prevention of infection]. PMID- 9370804 TI - [Hygiene nurse--measuring the standards of hygiene]. PMID- 9370805 TI - [Hygiene nurse--registration and prevention of pressure sores]. PMID- 9370806 TI - [Hygiene nurse--key persons in urinary incontinence]. PMID- 9370807 TI - [Hygiene nurse--spot-checking is a good work tool]. PMID- 9370808 TI - [EU (European Union)--common policy for blood and organs]. PMID- 9370809 TI - [Internet--hospitals go online]. PMID- 9370810 TI - [The use of nursing homes for drug addicts]. PMID- 9370811 TI - [Planetree models--welfare first and foremost]. PMID- 9370813 TI - [Hospitalization--a course to health]. PMID- 9370814 TI - [Ugh, that smells bad!]. PMID- 9370815 TI - [Money and firm policies needed for it to be successful. Interview by Carina Roxstrom]. PMID- 9370816 TI - [ICN Congress]. PMID- 9370818 TI - [International Council of Nurses soon to exist 100 years]. PMID- 9370817 TI - [ICN Congress--legislation does not help in achieving equal pay for equal job. Interview by Kaj Nyman]. PMID- 9370819 TI - [ICN Congress-nurses should be in the political arena]. PMID- 9370820 TI - [ICN Congress--undisputed definition of nursing is needed. Interview by Susanna Stubbendorff]. PMID- 9370821 TI - [ICN Congress--Gunilla recommends international congresses. Interview by Elisabet Forslind]. PMID- 9370822 TI - [ICN Congress--the dying need good care]. PMID- 9370823 TI - [Entrepreneurs--nurses who want to fulfill themselves]. PMID- 9370824 TI - [Nursing staff chooses coffee-break before patients. Wide gap between theory and practice demonstrated by research report. Interview by Anders Olsson]. PMID- 9370825 TI - [A common language gives recognition to nursing. Interview by Birgitta Dalenstam]. PMID- 9370826 TI - [Quick decisions in nurse's telephone counseling]. PMID- 9370828 TI - [Personnel acquitted in spite of criticism]. PMID- 9370827 TI - [Route of infection in ABC (Alternative Birth Center) has never been found]. PMID- 9370830 TI - ["Don't forget that this is your child's child!". Interview by Ingela Bjorck]. PMID- 9370829 TI - ["Consider how much has changed". Grandpa and grandma take a course in a women's clinic]. PMID- 9370831 TI - [Inventors' school for nurses]. PMID- 9370832 TI - [The Association should only be called Vardforbundet (Health Care Society). One of the issues for the November congress]. PMID- 9370833 TI - Females and their variability. PMID- 9370834 TI - The need for basic sciences in the understanding and practice of anaesthesia. AB - We conducted a survey using an unstructured, then a structured, questionnaire to determine the attitudes of 78 postfellowship anaesthetists to the Basic Sciences component of the part I examination for the FRCA. Seventy-two per cent replied. These anaesthetists felt that about 65% of the basic science syllabus was essential to the understanding and practice of everyday anaesthesia, but there was varying opinion as to the importance of specific topics. Cardiovascular, respiratory, central nervous system and renal physiology were all regarded as essential, as was the pharmacology of anaesthetic drugs. Topics regarded as irrelevant included biochemistry, endocrinology, membrane theory and immunology. Paradoxically, there were many topics which anaesthetists regarded as essential but on which they were unable to give a tutorial. There was little difference between the responses of consultants and trainees. This survey may help to identify a core syllabus on which the majority of anaesthetists agree but also suggests that the current syllabus is overloaded with detail that has no place in clinical practice. PMID- 9370835 TI - The effect of propofol on midazolam metabolism in human liver microsome suspension. AB - We have studied the inhibitory effects of propofol on the metabolism of midazolam using human liver microsomes. In addition, we also investigated whether the lipid in which propofol is solubilised inhibits the metabolism of midazolam. Only high concentrations of propofol (> 100 mmol), greater than those found in clinical practice, inhibited the metabolism of midazolam. The lipid had no effect on the metabolism of midazolam. This study differs from other laboratory studies looking at the inhibitory effects of propofol. These showed inhibition at concentrations similar to those seen in patients. The reasons for the differences may be explained by the use of different substrates or methodology. Propofol may be an enzyme inhibitor, but this remains to be shown to be important in patients. PMID- 9370836 TI - The influence of age upon opioid analgesic use in the patient-controlled analgesia (PCA) environment. AB - It is often asserted that older patients are more sensitive to opioid analgesics than younger patients but experimental evidence for this assertion remains sparse. Two studies were conducted investigating the relationship between age and opioid analgesic use in the patient-controlled analgesia environment. In study I, the relationship was analysed subsequent to our publication of a study investigating patients' responses to opioid use with patient-controlled analgesia. Fifty-five postoperative patients, stratified into 'older' and 'younger' patients by median age, received morphine or pethidine or fentanyl patient-controlled analgesia. A strong inverse relationship was found between age and fentanyl and morphine use but not between age and pethidine use. Study II was a retrospective study of the medical records of 199 patient-controlled analgesia patients who had received morphine or pethidine patient-controlled analgesia; there were insufficient patients who had used fentanyl for a reasonable sample. There was a difference in morphine use with the younger patients using significantly more morphine than the older patients (< 60 years). Findings were less clear for patients receiving pethidine but there was an inverse correlation between age and pethidine use as well. Overall, the findings of these two studies supported the common clinical belief that older patients require less opioids than younger patients. PMID- 9370837 TI - Magnesium sulphate for control of spasms in severe tetanus. Can we avoid sedation and artificial ventilation? AB - A prospective pilot study was undertaken to investigate the ability of magnesium sulphate to control the spasms of severe tetanus without the need for sedation and artificial ventilation. All eight patients admitted with severe tetanus to our intensive care unit within the last year were given magnesium sulphate intravenously as a 5-g loading dose followed by an infusion of 2-3 gh-1. The infusion rate was increased to control spasms while retaining the patella tendon reflex, which proved a valid guide to avoid overdose. Spasms were effectively controlled and serum magnesium concentrations were maintained within the therapeutic range. Spontaneous ventilation was adequate, ventilatory support being required only for the management of lung pathology. There was no evidence of cardiovascular instability due to sympathetic over activity. No supplementary sedation was required for the control of spasms or autonomic dysfunction during magnesium therapy. We conclude that magnesium sulphate can be used as the sole agent for the control of spasms in tetanus without the need for sedation and artificial ventilation. PMID- 9370838 TI - Postoperative symptoms at home following day-case surgery in children: a multicentre survey of 551 children. AB - The incidence and duration of postoperative symptoms in children at home following day-case anaesthesia and surgery was evaluated using a questionnaire completed by parents of 551 children aged 4 months to 13.4 years (mean 3.8 years). They also evaluated the instructions given in hospital for care at home. The incidence of all symptoms was highest at home on the day of the operation. No postoperative symptoms were reported in 79 (14%) children. The incidence of pain was 56% and the only significant predictor was the type of operation, tonsillectomy being the most problematic (mild pain in 38% and severe in 25%; pain lasted 7 days or longer in 33%). Analgesics were given to 78% of all the children reported to have pain on the day of the operation, to 60% the next day and later to 58%; 19 (3%) children were given more than two doses per day. The instructions given in hospital for the treatment of pain were considered inadequated by 12% of parents. Postoperative nausea and vomiting occurred in 13% of children. Predictors by multiple stepwise logistic regression analysis were emetic symptoms in hospital, pain at home, age > 5 years and administration of postoperative opioid (pethidine or fentanyl). Opioid given during anaesthesia (fentanyl or alfentanil) did not increase the incidence. Emetic symptoms were most common after tonsillectomy (31%). The highest incidences of emetic symptoms (37%), sedation (96%) and dizziness (41%) occurred in children who had been given fentanyl for postoperative pain. Undertreatment of nausea in hospital was evident as only two children had received anti-emetics, even though 61 were reported to have emetic symptoms. Administration of effective anti-emetics should be encouraged, as emetic symptoms in hospital were the most significant predictor of nausea and vomiting at home. Treatment of pain at home and instructions for treatment of pain need to be improved. PMID- 9370839 TI - Behavioural changes in children following day-case surgery: a 4-week follow-up of 551 children. AB - The purpose of this prospective multicentre survey was to evaluate the occurrence and the type of changes in children's behaviour during the first 4 weeks following the day of surgery, and to assess the significance of some patient related factors on the incidence. Pre- and postoperative questionnaires were completed by the parents of 551 children aged 4 months to 13.4 years in five hospitals incorporating nine operative units in Northern Finland. The overall incidence of problematical behavioural changes was 47% and that of beneficial changes 17%. Problematical changes were most common in the 1.0 to 2.9 year olds and the incidence decreased significantly from 46% on the day of the operation to 9% 4 weeks later (p < 0.0001). Predictors by multiple logistic regression analysis were age, mild pain at home following surgery, severe pain and a previous bad experience of health care which had adversely affected the attitude of the child towards doctors or nurses. Hospital influenced playing was a significant factor 3 and 4 weeks after the operation. By the 4th week, beneficial and problematical changes were equally common (9%). Gender, previous operations and experience of repeated paracenteses (for treatment of middle ear infection) did not have a significant effect on the incidence. Pain on the day of the operation predicted the occurrence of behavioural problems up to the 4th week, 2 4 weeks longer than the duration of pain itself. The results emphasise the importance of effective prevention of postoperative pain as well as the importance of avoiding unpleasant experiences in all contacts children have with health care. Playing could perhaps be used to help children cope with a short hospital experience. PMID- 9370840 TI - Damage to the laryngeal mask by residual fluid in the cuff. AB - It has been suggested that, in some situations, the cuff of the laryngeal mask should be filled with fluid. We speculated that this practice might damage the device during sterilisation in an autoclave. We studied whether injection of a small volume of water into the cuff of the laryngeal mask and subsequent sterilisation affected the integrity of the cuff. First, a pressure-volume relationship for each of 20 new masks was obtained by inflating the cuff with increasing volumes of air (5-45 ml). The masks were then randomly allocated into four groups (W0, W0.25, W0.5 or W1.0), 0, 0.25, 0.5 or 1.0 ml of water was injected into the cuff and the mask was then sterilised in an autoclave. After sterilisation, the shape of the cuff was examined and pressure-volume relationships were obtained again. The baseline intracuff pressures were similar in the four groups. After sterilisation, the pressure was significantly lower in groups W0.25, W0.5 and W1.0 than in group W0 (p < 0.05). Two masks in group W1.0 lost their integrity, resulting in herniation of and rupture of the cuff. We conclude that the cuff of the laryngeal mask should not be inflated with fluid unless the device is discarded afterwards. PMID- 9370841 TI - Selective serotonin reuptake inhibitors. Pharmacology and clinical implications in anaesthesia and critical care medicine. AB - The newer, selective serotonin reuptake inhibitors are increasingly used in psychiatry in both children and adults. Although they have fewer side-effects, they can cause significant physiological changes and drug interactions which have implications for the anaesthetist and the critical care physician, especially the potential to induce the serotonin syndrome. PMID- 9370842 TI - Acute superior vena caval syndrome with airway obstruction following elective mediastinoscopy. AB - A 47-year-old female patient had a subclinical superior vena caval syndrome which developed into the 'full blown' acute condition when she was placed into the left lateral position after mediastinoscopy. She developed airway obstruction requiring urgent re-intubation and subsequent admission to the intensive care unit. This subclinical condition might have been suspected pre-operatively if closer attention had been paid to the history, physical examination and review of the computerised axial tomography scan: she had a history of intermittent dysponea, wheeze and cough which was worse on waking and improved as the day progressed, she had a positive Pemberton's sign and the computerised axial tomography scan showed that the lesion was encroaching on the superior vena cava. PMID- 9370843 TI - Mechanical obstruction in the anaesthesia delivery-system mimicking severe bronchospasm. AB - We present a case where mechanical obstruction in the anaesthesia delivery system caused by plastic wrapping from a filter was misinterpreted as severe bronchospasm. The patient suffered severe hypoxia before the problem was solved by using a free-standing self-expanding ventilation bag. This near-fatal incident emphasises the importance of thorough equipment checking routines, rapid troubleshooting and how equipment failure may be misinterpreted as a medical complication. It also shows how transparent container material can become a medical hazard. PMID- 9370844 TI - Halothane treatment of severe asthma to avoid mechanical ventilation. AB - A 41-year-old woman was admitted to the Intensive Care Unit with a severe exacerbation of asthma. She was exhausted despite maximal standard medical treatment. Instead of tracheal intubation and mechanical ventilation a subanaesthetic dose of halothane was delivered in 100% oxygen using a close fitting face mask. Her bronchospasm resolved within minutes. The argument for using inhaled halothane to avoid tracheal intubation, mechanical ventilation and their side-effects is presented. PMID- 9370845 TI - Intubating conditions using cisatracurium after induction of anaesthesia with thiopentone. AB - We studied tracheal intubation conditions produced by the muscle relaxant, cisatracurium, following induction of anaesthesia with fentanyl (2 micrograms.kg 1) and thiopentone (6 mg.kg-1). Sixty patients were randomly assigned to receive cisatracurium in a single bolus dose of either 0.15 or 0.20 mg.kg-1. Tracheal intubation was commenced 120 s after injection of the relaxant. The mean (SD) time taken to achieve intubation was significantly shorter in the 0.20 mg.kg-1 group (137 (16) s) than the 0.15 mg.kg-1 group (149 (12) s; p < 0.05). The intubating conditions were better after the larger dose. Our results suggest that when anaesthesia is induced using thiopentone, a dose of 0.20 mg.kg-1 of cisatracurium is recommended to ensure satisfactory intubating conditions. PMID- 9370846 TI - The effect of co-induction with midazolam upon recovery from propofol infusion anaesthesia. AB - Forty-eight patients undergoing day-case anaesthesia were asked to complete pre- and postoperative tests of psychomotor function in order to study the influence of co-induction with midazolam in conjunction with propofol/alfentanil anaesthesia on postoperative psychomotor recovery. The study was placebo controlled and double blind with patients receiving either 0.03 mg.kg-1 of midazolam or saline 2 min before induction of anaesthesia with propofol and alfentanil. Patients who underwent co-induction with midazolam had significantly impaired concentration and rapidity of response but improved accuracy and vigilance when compared with those who received saline. The study confirmed that co-induction with a subanaesthetic dose of midazolam reduced the induction dose of propofol by up to 50%. We conclude that co-induction with midazolam reduces psychomotor recovery in the immediate postoperative phase following propofol infusion anaesthesia. PMID- 9370847 TI - A comparative multicentre trial of spinal needles for caesarean section. AB - We studied 681 patients in a randomised, multicentre, double-blind, parallel group trial designed to assess the incidence of headache following spinal anaesthesia for Caesarean section using four different pencil point spinal needles. The needles used were: Whitacre 25G (n = 170), Polymedic 25G (n = 170), Sprotte 24G (n = 173) and Polymedic 24G (n = 168). The incidence of all headaches prior to discharge was 11.1%. Only five headaches (0.75%) were severe with features of post dural puncture headache (PDPH) and required an epidural blood patch: Whitacre 25G = 0, Polymedic 25G = 1 (0.6%), Sprotte 24G = 2 (1.2%), Polymedic 24G = 2 (1.2%). There was no statistically significant difference between the four groups for PDPH. We conclude that all four needles studied performed satisfactorily and comparably. PMID- 9370848 TI - The effect of a toothguard on the difficulty of intubation. AB - Dental damage is the most common reason for complaints against anaesthetists. The purpose of this study was to investigate the common belief that the use of a toothguard at the time of intubation causes intubation to be more difficult. We studied 80 patients, half of whom were intubated with a toothguard in situ and the other half intubated without a toothguard. The time taken from mouth opening to successful passage of the tracheal tube through the vocal cords was measured. In the toothguard group, the recorded time also included the time taken to insert the toothguard. The median time to intubation in the group with a toothguard was 24 s and the median time to intubation in the group without a toothguard was 17 s. The difference of 7 s in the time to intubation was statistically significant (p = 0.0003). As the recorded times also included the time taken to insert the toothguard, we do not regard this result to be clinically significant and believe that anaesthetists should think carefully before disregarding this simple protective device. PMID- 9370849 TI - Anaesthesia and the Research Assessment Exercise. PMID- 9370850 TI - Predictors of postoperative myocardial ischemia. PMID- 9370851 TI - Patient-controlled analgesia--who benefits? PMID- 9370852 TI - Reshaping the Macintosh blade. PMID- 9370853 TI - A simple method for confirming epidural catheter placement. PMID- 9370854 TI - Donepezil, Alzheimer's disease and suxamethonium. PMID- 9370856 TI - Force during laryngoscopy. PMID- 9370855 TI - Intrathecal neostigmine. PMID- 9370857 TI - Latex allergy. PMID- 9370858 TI - A fault in a loss of resistance device. PMID- 9370859 TI - Persistent problem with propofol ampoules. PMID- 9370860 TI - Spinal anaesthesia and Shy Drager syndrome. PMID- 9370861 TI - A survey of postoperative nausea and vomiting. PMID- 9370862 TI - Air versus saline. PMID- 9370863 TI - A therapeutic anaesthetic? Termination of broad-complex tachycardia during induction of general anaesthesia. PMID- 9370864 TI - Is Hartmann's the solution? PMID- 9370865 TI - Is Hartmann's the solution? PMID- 9370866 TI - Nalbuphine and pruritus. PMID- 9370867 TI - Ophthalmic surgery, local anaesthesia and supplemental oxygen. PMID- 9370869 TI - Feline fits. PMID- 9370868 TI - Complete airway obstruction during awake fibreoptic intubation. PMID- 9370870 TI - An improved technique for nasogastric tube insertion during general anaesthesia. PMID- 9370872 TI - How do bisphosphonates prevent fractures? PMID- 9370871 TI - Prevention of glucocorticoid induced osteoporosis. PMID- 9370873 TI - Fatal postoperative airway obstruction in a patient with rheumatoid arthritis. PMID- 9370874 TI - Long-term prognosis of reactive salmonella arthritis. AB - OBJECTIVES: Reactive joint complications triggered by salmonella gastroenteritis are increasingly reported, but the outcome and long term prognosis of the patients is incompletely known. This study looked at the prognosis of salmonella arthritis in patients hospitalised in 1970-1986. METHODS: Hospital records from two hospitals in southern Finland were screened for patients with the discharge diagnosis of salmonellosis or reactive, postinfectious arthritis or Reiter's disease. For the patients with confirmed diagnosis of reactive salmonella arthritis, data about the acute disease were collected from the hospital records. A follow up study was performed. RESULTS: There were 63 patients (28 women, 35 men, mean age 36.5 years) with salmonella arthritis. Urethritis occurred in 27%, eye inflammation in 13%, and low back pain in 44% of the patients. HLA-B27 was present in 88%. More men than women were HLA-B27 positive. HLA-B27 positive patients had higher erythrocyte sedimentation rate (mean 80.9 v 46.5 mm 1st h, p = 0.0180). Also, extra-articular features and radiological sacroiliitis were seen only in HLA-B27 positive patients. A follow up study was performed on 50 patients mean 11.0 (range 5-22 years) later. Twenty patients had recovered completely. Ten patients had mild joint symptoms, 11 patients had had a new acute transient arthritis, and five acute iritis. Eight patients had developed chronic spondyloarthropathy. Radiological sacroiliitis was seen in six of 44 patients, more frequently in male than in female patients (32% v 0%; p = 0.0289). Recurrent or chronic arthritis, iritis or radiological sacroiliitis developed only in HLA B27 positive patients. CONCLUSION: Joint symptoms are common after reactive salmonella arthritis. HLA-B27 contributes to the severity of acute disease and to the late prognosis. PMID- 9370875 TI - Prevalence of Sjogren's syndrome in a closed rural community. AB - OBJECTIVE: To define the prevalence of Sjogren's syndrome (SS) through an epidemiological survey in a closed rural community. The classification of SS is based on the validated criteria reported by a multicentre study performed in Europe and supported by the Epidemiology Committee of the European Community (EEC COMAC Epidemiology). METHODS: The population under study consisted of 837 women aged 18 years or older, residing in the Astakos community of Aitoloakarnania, Greece. The study protocol was subdivided in two parts. In part I, an exhaustive epidemiological survey of these women was conducted in July and August of 1992. The validated questionnaire used in the survey assesses both ocular and oral involvement. In part II, 45 of the women reporting symptoms of both dry eye and dry mouth were approached for a full examination based on the validated set of classification criteria of SS. The full complement of the diagnostic tests was performed on 35 of these women. A subject is classified as a definite primary SS case if at least four of six items of the subject's test items are positive. If three of six items are positive the subject is classified as a probable primary SS case. RESULTS: The classification criteria for definite primary SS were satisfied by five women. This number corresponds to an estimated prevalence of 0.60% (exact 95% CI 0.19%, 1.39%). Probable primary SS was diagnosed for 25 women (prevalence = 2.99%). CONCLUSION: Because of the loss of follow up (10 of 45) and the use of slightly stricter criteria for inclusion of possible SS cases in part II of the study, we consider our estimate of the prevalence of SS to be conservative. This study concurring with other recent reports, suggests that SS is more prevalent than previously thought. PMID- 9370876 TI - Unusual and memorable. Asymmetric metacarpal periostitis. PMID- 9370877 TI - Measurement of synovial lining volume by magnetic resonance imaging of the knee in chronic synovitis. AB - OBJECTIVES: Current methods of monitoring chronic synovitis in a single joint rely on clinical examination derived indices, such as the detection of synovial thickening. This study aimed to develop a reproducible method for quantifying the volume of synovial lining in chronic synovitis using contrast enhanced magnetic resonance (MR) imaging. METHODS: The knees of 18 patients with chronic synovitis were examined (34 studies). A 2D T1 weighted FLASH sequence was used to evaluate the temporal enhancement of synovial structures after intravenous contrast. Synovial lining volume was calculated from subtraction of pre and post enhancement 3D T1 weighted MP RAGE images with thresholding and pixel counting. Eleven patients were examined before and after intra-articular glucocorticoid (mean interval 14 weeks) and MR data compared with changes in clinical examination derived indices of disease activity. RESULTS: Synovial lining volume varied from 52-267 ml. The coefficient of variation in volume calculation was 3.5% for a single observer and was 3.8% for two observers. Synovial lining volume was quantified in all patients where synovial lining thickening could not be detected clinically. A decrease in synovial lining volume of > 40% was associated with an improvement in synovial lining thickening, detected clinically. Decreases in synovial lining volume were quantified by MR in two of three patients where changes in clinical examination derived indices were inconsistent. CONCLUSIONS: A reproducible method of estimating the volume of synovial lining in patients with chronic synovitis has been developed. MR measurement of synovial lining volume may quantify changes in chronic synovitis that remain unidentified by clinical measures. PMID- 9370878 TI - Intractable diarrhoea associated with secondary amyloidosis in rheumatoid arthritis. AB - OBJECTIVE: To examine the clinical characteristics of intractable diarrhoea associated with secondary amyloidosis in rheumatoid arthritis (RA). METHODS: Of 179 RA patients with biopsy confirmed secondary amyloidosis, 24 cases (23 women and one man) with intractable diarrhoea lasting for more than one month were retrospectively evaluated. RESULTS: The mean (SD) duration of diarrhoea was 87 (64) days. Prodromal symptoms of gastrointestinal dysfunction (n = 21) and impaired peristalsis (n = 16) were observed. Laboratory data showed hypoproteinaemia (4.7 (0.85) g/dl) caused by malabsorption or protein loss and high values of C reactive protein (17.0 (9.3) mg/dl). Recurrence of intractable diarrhoea (n = 4) and transition from intractable diarrhoea to other gastrointestinal problems of amyloidosis (ischaemic colitis (n = 2) and intestinal pseudo-obstruction (n = 4)) were observed. In 19 patients (25 episodes) the duration of intravenous hyperalimentation at remission (18 episodes) was 68 (52) days. Corticosteroid pulse therapy was administered to 10 patients (11 times) and the time elapsed from the end of corticosteroid pulse therapy to the end of diarrhoea was 18 (14) days. One and five year survival rates after the onset of intractable diarrhoea were 73.4% and 38.9%. Seven of 13 patients (54%) had died as a result of infectious diseases. CONCLUSION: Intractable diarrhoea associated with secondary amyloidosis in RA is a serious clinical entity and the prognosis is poor. Although it is assumed that intravenous hyperalimentation treatment and corticosteroid pulse therapy are favourable regimens for intractable diarrhoea, the patients should be monitored for possible infectious complications. PMID- 9370879 TI - Gene expression of matrix metalloproteinases 1, 3, and 9 by chondrocytes in osteoarthritic human knee articular cartilage is zone and grade specific. AB - OBJECTIVES: Matrix metalloproteinases (MMPs) are thought to be major mediators of cartilage destruction. Osteoarthritis (OA) is characterised by cartilage degradation. This study explores gene expression of three MMPs in articular chondrocytes during the histological development of the cartilage lesion of OA. METHODS: Biopsy specimens of human normal and OA cartilage, classified into four grades on the basis of histology, were probed for MMPs 1, 3, and 9 using 35S labelled cDNA probes. The signal was measured at four different depths (zones) using an automated image analyser and compared with signal from sections probed with lambda DNA. Rheumatoid synovium was used as a positive control for MMP gene expression. RESULTS: Rheumatoid tissue contained mRNA for all three MMPs. Expression in chondrocytes varied with the depth of the chondrocyte in the cartilage and the histomorphological extent of the OA changes. There was no detectable mRNA signal for these three MMPs in normal cartilage. In general, in OA, MMP-1 gene expression was greatest in the superficial cartilage in established disease. By contrast mRNAs for MMP-3 and 9 were expressed deeper in the cartilage, MMP-9 early in disease and MMP-3 with a biphasic pattern in early and late stage disease, most pronounced in the latter. This was a consequence of differential expression in single cells and chondrocyte clusters in late disease. CONCLUSION: The data indicate that expression of genes for MMPs 1, 3, and 9 is differentially regulated in human articular chondrocytes and, in individual cells, is related to the depth of the chondrocyte below the cartilage surface and the nature and extent of the cartilage lesion. PMID- 9370880 TI - Plasminogen activation in synovial tissues: differences between normal, osteoarthritis, and rheumatoid arthritis joints. AB - OBJECTIVE: To analyse the functional activity of the plasminogen activators urokinase (uPA) and tissue type plasminogen activator (tPA) in human synovial membrane, and to compare the pattern of expression between normal, osteoarthritic, and rheumatoid synovium. The molecular mechanisms underlying differences in PA activities between normal and pathological synovial tissues have been further examined. METHODS: Synovial membranes from seven normal (N) subjects, 14 osteoarthritis (OA), and 10 rheumatoid arthritis (RA) patients were analysed for plasminogen activator activity by conventional zymography and in situ zymography on tissue sections. The tissue distribution of uPA, tPA, uPA receptor (uPAR), and plasminogen activator inhibitor type-1 (PAI-1) was studied by immunohistochemistry. uPA, tPA, uPAR, and PAI-1 mRNA values and mRNA distribution were assessed by northern blot and in situ hybridisations respectively. RESULTS: All normal and most OA synovial tissues expressed predominantly tPA catalysed proteolytic activity mainly associated to the synovial vasculature. In some OA, tPA activity was expressed together with variable amounts of uPA mediated activity. By contrast, most RA synovial tissues exhibited considerably increased uPA activity over the proliferative lining areas, while tPA activity was reduced when compared with N and OA synovial tissues. This increase in uPA activity was associated with increased levels of uPA antigen and its corresponding mRNA, which were localised over the synovial proliferative lining areas. In addition, in RA tissues, expression of the specific uPA receptor (uPAR) and of the plasminogen activator inhibitor-type 1 PMID- 9370881 TI - Relations between synovial fluid and serum concentrations of osteocalcin and other markers of joint tissue turnover in the knee joint compared with peripheral blood. AB - OBJECTIVE: To determine if osteocalcin (OC) is locally produced in the joint and to study the relation between markers of bone, cartilage, and synovial tissue turnover. METHODS: The concentrations of OC, keratan sulphate epitope (5D4), and hyaluronate (HA) were measured in paired serum and synovial fluid in 10 healthy volunteers and 15 patients with osteoarthritis (OA) and 16 with rheumatoid arthritis (RA). OC was measured with a commercial immunoradiometric assay and concentrations of 5D4 and HA were measured using enzyme linked immunosorbent inhibition assays. RESULTS: Synovial fluid OC was found to be significantly lower than serum (p < 0.001) in all patients and controls. Synovial fluid OC concentrations were directly correlated with serum concentrations (r = 0.63, p < 0.001) and with age (r = 0.48, p < 0.01). There were also some relations between OC, HA, and 5D4 in patients with OA and RA. The OC concentrations were directly correlated with HA (r = 0.68, p < 0.01) in OA serum and there was a similar correlation in RA synovial fluid (r = 0.69, p < 0.01). A weak negative correlation was found between OC and 5D4 in OA serum (r = -0.55, p = 0.035) while a weak positive correlation was found in RA serum (r = 0.53, p = 0.034). CONCLUSIONS: These results show that more OC is present in the circulation than in knee joint fluids suggesting that synovial fluid OC may be derived from the blood. PMID- 9370883 TI - Remitting distal lower extremity swelling with pitting oedema in acute sarcoidosis. PMID- 9370882 TI - Renal vein thrombosis in Chinese patients with systemic lupus erythematosus. AB - OBJECTIVES: To evaluate the risk factors associated with renal vein thrombosis (RVT) in Chinese patients with systemic lupus erythematosus (SLE). METHODS: Data on clinical symptoms, renal biopsy, antiphospholipid antibody syndrome profile, and serological examinations of lupus features were examined retrospectively in six patients with RVT confirmed by angiography from a total of 625 patients with SLE over a 14 year period (1982-1996). RESULTS: The lupus patients with RVT did not have acute symptoms of severe flank pain, haematuria, and oligouria. In contrast, most patients were suspected to have RVT because of peripheral oedema and worsening proteinuria. Roentgenological examinations (including renal sonography, renal computer tomography, or renal Doppler, or all three) were positive only in some patients. Positive antiphospholipid antibody profiles were found in four of six lupus patients. By renal biopsy, only two samples were confirmed as World Health Organisation (WHO) class V lupus membranous glomerulonephritis. The others were class IV in three patients, and class III in the remaining one. No RVT was found in lupus patients without nephrotic syndrome. Peripheral thrombophlebitis was, however, noted in only one patient. CONCLUSION: Nephrotic syndrome could be a distinct risk factor in the development of RVT in Chinese SLE patients, in contrast with that reported in white populations in whom the peripheral thrombotic events were recognised as a determining factor. PMID- 9370884 TI - Further evidence that low androgen values are a cause of rheumatoid arthritis: the response of rheumatoid arthritis to seriously stressful life events. PMID- 9370885 TI - Acute adrenal failure secondary to bilateral infarction of the adrenal glands as the first manifestation of primary antiphospholipid antibody syndrome. PMID- 9370886 TI - Echocardiographic findings in primary Sjogren's syndrome. PMID- 9370887 TI - An acute multiorgan thrombotic disorder associated with antiphospholipid antibodies; two 'catastrophic' cases. PMID- 9370888 TI - Prevalence of hepatitis C virus antibody in patients with systemic lupus erythematosus. PMID- 9370889 TI - Gouty arthritis in the manubriosternal joint. PMID- 9370890 TI - Late onset spondyloarthropathy: comparison with early onset patients. PMID- 9370891 TI - Health education: evidence of effectiveness. PMID- 9370892 TI - Vitamin A prophylaxis. PMID- 9370893 TI - Routine male neonatal circumcision and risk of infection with HIV-1 and other sexually transmitted diseases. PMID- 9370894 TI - Randomised controlled trial of zinc supplementation in malnourished Bangladeshi children with acute diarrhoea. AB - OBJECTIVE: To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN: Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING: A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS: 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES: Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS: Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS: Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished. PMID- 9370895 TI - Differentiation of osmotic and secretory diarrhoea by stool carbohydrate and osmolar gap measurements. AB - Clinical features and laboratory tests that determine carbohydrate in faeces were evaluated to determine which was best able to distinguish between osmotic and secretory diarrhoea in infants and children. For this purpose 80 boys aged 3 to 24 months, with acute watery diarrhoea, were studied prospectively. The faecal osmolar gap (FOG) was calculated as: serum osmolarity-[2 x (faecal sodium + potassium concentration)]. Fifty eight patients were classified as having predominantly osmotic diarrhoea (FOG > 100 mosmol/l), and 22 as having predominantly secretory diarrhoea (FOG < or = 100 mosmol/l). The two groups were comparable in their clinical features on admission, in the results of blood and urine tests, and in the evolution of their diarrhoeal illness. Evidence of steatorrhoea (by positive Sudan III test) and of acid faecal pH on admission were significantly more frequent in patients with osmotic diarrhoea. Mean (SD) faecal osmolarity was not significantly different between the two groups (319 (80) mosmol/l in secretory diarrhoea v 361 (123) mosmol/l in osmotic diarrhoea). Tests for reducing substances in faeces such as Benedict's test--with and without hydrolysis--and glucose strip, all showed a positive and significant association with osmotic diarrhoea (p < 0.05, < 0.025, < 0.05, respectively). The presence of excess reducing substances (Benedict's test with hydrolysis > 2+) on admission was the most sensitive and specific test with the best predictive value for differentiating between the two types of watery diarrhoea. PMID- 9370896 TI - Changing infant feeding practices and declining incidence of coeliac disease in West Somerset. AB - An association was investigated between changing infant feeding practices and a declining incidence of childhood coeliac disease and transient gluten intolerance (TGI) in West Somerset, England during 1971-92. Dietary histories of 18 patients with coeliac disease were compared with 23 controls during 1971-80 and eight patients with coeliac disease and 39 controls during 1981-92. Our findings showed that the declining incidence of coeliac disease and TGI were associated with changing infant feeding practices, characterised by the later introduction of dietary gluten, an increased use of baby rice and gluten free foods for weaning, and an increased incidence of initial breast feeding. PMID- 9370897 TI - Rising incidence of type 1 diabetes in Scottish children, 1984-93. The Scottish Study Group for the Care of Young Diabetics. AB - OBJECTIVES: To calculate the incidence of type 1 diabetes in Scottish children aged less than 15 years between 1984 and 1993; to examine changes in incidence; and to calculate the prevalence of diabetes at the end of this period. DESIGN: Three data sources were used to construct the Scottish Study Group for the Care of Young Diabetics register: active reporting of all new cases; reports from the Scottish Morbidity Register 1; and local registers. SUBJECTS: All children resident in Scotland diagnosed with primary insulin dependent diabetes mellitus when less than 15 years of age between 1984 and 1993. MAIN OUTCOME MEASURES: Annual incidence and prevalence rate for Scotland; time trend in incidence over the 10 years; differences in incidence between the three different age groups; and completeness of the register. RESULTS: The average annual incidence for Scotland was 23.9/100,000 children. The prevalence rate was 1.5/1000 in 1993. A total of 2326 cases was identified from the three sources. Capture-recapture analysis suggests a case ascertainment of 98.6%. The annual incidence rates increased at a rate of 2% each year (rate ratio = 1.02, 95% confidence interval (CI) 1.01 to 1.03). The incidence was higher in boys than girls (rate ratio = 1.08, 95% CI 1.00 to 1.18), and the incidence rates increased with age: 15.3/100,000/year for age 0-4 years, 24.4/ 100,000/year for age 5-9 years, and 31.9/ 100,000/year for age 10-14 years. CONCLUSIONS: The incidence of type 1 diabetes in Scotland is increasing and the prevalence is relatively high. These findings have important implications for health service resource allocation. The Scottish Study Group for the Care of Young Diabetics' register provides a base for monitoring and research. PMID- 9370898 TI - Randomised controlled trial of growth effect of hydrocortisone in congenital adrenal hyperplasia. AB - The influence of 15 or 25 mg/m2 of daily oral hydrocortisone with fludrocortisone 0.1 mg/day on growth and laboratory findings was evaluated in a prospective randomised crossover trial over 12 months in 26 children with 21-hydroxylase deficiency. Nine non-salt losers had fludrocortisone stopped for a further six month period. Height velocity was significantly decreased during treatment with 25 mg/m2 as compared with 15 mg/m2. This was the most sensitive indicator of corticosteroid treatment excess. A dose dependent effect upon plasma concentrations of 17-hydroxyprogesterone, testosterone, and androstenedione was found but increased values were still detected in more than half of the determinations made during the 25 mg/m2 period. Height velocity and 17 hydroxyprogesterone concentrations were positively correlated. Growth hormone response to clonidine stimulation and insulin-like growth factor-1 concentrations were both within reference values and there was no difference between treatment periods. Withdrawal of fludrocortisone did not result in any difference for the non-salt losers. It was concluded that 25 mg/m2 of hydrocortisone depressed growth in children with congenital adrenal hyperplasia, and that full suppression, or even normalisation, of plasma concentrations of 17 hydroxyprogesterone and androgens should not be considered a treatment goal, but instead an indication of corticosteroid treatment excess. PMID- 9370899 TI - Educational progress, behaviour, and motor skills at 10 years in early treated congenital hypothyroidism. AB - AIM: To assess educational attainments, behaviour, and motor skills at 10 years of age in a group of children with congenital hypothyroidism identified by neonatal screening. SUBJECTS: 59 children with congenital hypothyroidism born in 1978-81, 31 cases with pretreatment thyroxine (T4) values of 40 nmol/l or below (group I) and 28 less severe cases with T4 values over 40 nmol/l (group II), together with 59 classroom control children matched for age, sex, social class, and main language spoken at home. METHODS: The Neale analysis of reading ability; the child health and education study written test of mathematics; Rutter behaviour questionnaires for parents and teachers; the Oseretsky test of motor proficiency (short form). RESULTS: On all measures the congenital hypothyroidism children in group I had less satisfactory scores for educational attainments, behaviour, and motor skills than those in group II and controls. For reading the differences were small and did not reach statistical significance, but the deficits in mathematics and total motor skills were statistically significant (p < 0.01). There were more striking and statistically significant differences in behaviour scores, particularly with respect to attentional difficulties. Although less striking, these were also apparent in the group II children with mild hypothyroidism. CONCLUSIONS: At the age of 10 years severe congenital hypothyroidism is associated with some mild impairment in educational and motor attainments. Behaviour problems are also common, even in some children with less severe congenital hypothyroidism. PMID- 9370900 TI - Hepatitis GB virus-C/hepatitis G virus infection in liver disease. AB - Hepatitis GB virus-C (HGBV-C)/hepatitis G virus (HGV) infection was investigated in 106 children with liver disease (54 boys and 52 girls, mean age 7.3 years); 12 with chronic hepatitis C virus infection, 29 with positive hepatitis B surface antigen, nine with idiopathic fulminant hepatic failure, seven with graft dysfunction after liver transplantation associated with autoimmune features, 20 with cryptogenic liver disease, and 29 with autoimmune liver disease. HGV RNA detected by reverse transcription polymerase chain reaction was found to be positive in 4/106 patients (3.8%). Risk factors were identified in three patients, including blood transfusion and/or medical treatment in Eastern Europe. The prevalence was higher than that of blood donors but lower than that of 2 adult patients with liver disease. HGV is not associated with any specific disease group and does not seem to be a major aetiological agent of liver disease in childhood in the UK. PMID- 9370902 TI - Increased plasma malondialdehyde associated with cerebellar structural defects. AB - BACKGROUND: Malondialdehyde (MDA) in plasma is regarded as an indicator for increased lipid peroxidation. METHOD: Measurements of MDA concentrations in plasma were compared among healthy children (n = 31), patients with neurological disorders or epileptic syndromes (n = 15), and children with pontocerebellar structural defects (n = 31), where the cause or genetic defect remained unknown. RESULTS: In healthy children the median MDA value was 5.86 nmol/ml (mean (SD) value: 6.25 (1.97), range: 3.76-11.19). For the group with various neurological disorders or epilepsy, the values were similar with the median value at 5.66 nmol/ml (range 0.22-10.86). Compared with healthy controls and the neurological/ epileptic group, the 31 children with pontocerebellar structural defects had significantly increased MDA values with a median value at 11.29 nmol/ml (mean (SD) value: 11.62 (3.27), range 3.65-19.22). IMPLICATION: These findings of increased plasma MDA in the majority of children with pontocerebellar structural defects of unknown origin raised the question whether increased lipid peroxidation leads to prenatal and postnatal pontocerebellar maldevelopment or degeneration. PMID- 9370901 TI - Impact of HIV on mortality from acute lower respiratory tract infection in rural Zambia. AB - AIMS: To establish the prevalence and clinical correlates of HIV among children with acute lower respiratory tract infection. METHODS: Children admitted to a rural Zambian hospital were studied over an eight month period. The diagnosis of acute lower respiratory tract infection was made clinically, according to World Health Organisation (WHO) criteria. Clinicians, who were unaware of the children's HIV status, prescribed antibiotic and supportive treatment according to WHO guidelines. HIV status was established using the polymerase chain reaction (Amplicor HIV1, Roche) applied to dried blood spots. RESULTS: Acute lower respiratory tract infection was diagnosed in 132 children (median age 8 months, range 1 month to 4 years). The WHO criteria for severe or very severe pneumonia were met by 96/132 patients (73%) and 21 patients (16%) died. HIV dried blood spot PCR was positive in 14 cases (11%), of whom four fulfilled the WHO clinical case definition for paediatric AIDS and five died. The group as a whole were malnourished, but the HIV positive children were more severely malnourished (mean z score for weight = -3.01) than the HIV negative children (mean z score = -1.73, p < 0.001). The relative risk of death was 2.6 in the HIV positive group but this was not significant (p = 0.079). CONCLUSIONS: An important minority of children with acute lower respiratory tract infection in rural Zambia will be infected with HIV. However, most HIV positive children presenting with respiratory infection will survive given simple antibiotic and supportive treatment. PMID- 9370903 TI - Serum lactate as a predictor of mortality after paediatric cardiac surgery. AB - OBJECTIVE: To assess the value of sequential lactate measurement in predicting postoperative mortality after surgery for complex congenital heart disease in children. DESIGN: Prospective observational study. SETTING: Sixteen bedded paediatric intensive care unit (PICU). SUBJECTS: Ninety nine children (90 survivors, nine non-survivors). MEASUREMENTS: Serum lactate and base deficit were measured on admission and every six hours thereafter. Data were analysed by Mann Whitney and Fisher's exact tests. RESULTS: There was considerable overlap in initial lactate values between the survivor and non-survivor groups. Initial lactate was significantly raised in non-survivors (median 8.7, range 1.9-17.6 mmol/l) compared with survivors (median 2.4, range 0.6-13.6 mmol/l) (p = 0.0002). Twenty one patients (21.1%) with initial lactate concentrations greater than 4.5 mmol/l survived to PICU discharge. Using receiver operating characteristic analysis an initial lactate of 6 mmol/l had the optimum predictive value for mortality. Initial postoperative serum lactate > 6 mmol/l predicted mortality with sensitivity 78%, specificity 83%, and positive predictive value of only 32%. CONCLUSION: Initial lactate concentrations have poor positive predictive value for mortality. The routine measurement of lactate for this purpose cannot be justified in clinical practice. PMID- 9370904 TI - Enhanced drug metabolism in young children with cystic fibrosis. AB - The effect of cystic fibrosis on caffeine metabolism was studied in young children using the caffeine breath test. Eight children with cystic fibrosis aged 2-6 years and nine age matched controls were studied on a single occasion, and the cumulative percentage of labelled caffeine exhaled as carbon dioxide measured over two hours. This was significantly higher in the patients with cystic fibrosis than in controls, suggesting an increase in the CYP1A2 metabolic pathway in the former. The fact that these were young children with minimal lung and liver disease suggests that enhanced drug metabolism in children with cystic fibrosis is hereditary rather than secondary to lung and liver damage. PMID- 9370905 TI - High incidence of Down's syndrome in infants of diabetic mothers. AB - The incidence of Down's syndrome was studied in 1870 infants of diabetic mothers out of 22,300 neonates born between January 1987 and April 1994 in our institution. All pregnancies were screened for diabetes and all cases of Down's syndrome were confirmed by chromosome analysis. Down's syndrome (all trisomy 21) was diagnosed in 35 infants: seven were born to mothers with gestational diabetes and 28 to non-diabetic mothers. The incidence of Down's syndrome was higher in infants of diabetic mothers (3.75 per 1000 v 1.36 per 1000) (p = 0.02) with a relative risk of 2.75. No significant difference was found in maternal age between both groups (p = 0.67) and the rate of Down's syndrome was higher in infants of diabetic mothers when compared with infants of non-diabetic mothers of similar age. Down's syndrome should be added to the congenital malformations already known to occur more frequently in infants of diabetic mothers. PMID- 9370907 TI - Liver transplant for giant cell hepatitis with autoimmune haemolytic anaemia. AB - Giant cell hepatitis (CGH) with autoimmune haemolytic anaemia (AHA) is a distinct entity with an aggressive course. Immunosuppression may help early disease. A case is reported of a child with GCH and AHA with early disease recurrence after liver transplantation for end stage liver disease. PMID- 9370906 TI - The spectrum of Evans' syndrome. AB - Eleven patients (10 boys, one girl) with Evans' syndrome with a median follow up time of 8.0 years were evaluated retrospectively. Six patients had either persistent hepatosplenomegaly or generalised lymphadenopathy, or both. In five patients, an increase in lymph node and/or spleen size was observed during the exacerbations of cytopenias. Seven patients had quantitative serum immunoglobulin abnormalities at the time of presentation. There were associated systemic manifestations in nine patients. Various forms of treatment were used with mixed results. Four patients died from sepsis and haemorrhage; four had complete recovery--two after splenectomy. These findings show that Evans' syndrome is a heterogeneous disorder with significant morbidity and mortality. High incidence of quantitative serum immunoglobulin abnormalities, lymphoid hyperplasia, and associated systemic manifestations suggest that Evans' syndrome may represent a stage of a more broad spectrum, generalised immune dysregulation. PMID- 9370908 TI - Hypogammaglobulinaemia in a patient with ring chromosome 21. AB - An 8 year old boy with ring chromosome 21 who was susceptible to sinorespiratory infections due to hypogammaglobulinaemia is reported. He presented with the characteristic features of monosomy 21 syndrome, such as psychomotor retardation, hypertonia, large saccular ears, prominent nasal bridge, micrognathia, thrombocytopenia, and patent ductus arteriosus. His serum IgG concentration was less than 1.5 g/l at 3 years and 6 months of age after repeated hospitalisations with pneumonia, otitis media, and convulsions. Regular replacement of intravenous gammaglobulin effectively reduced such infectious episodes. A predisposition to infection in patients with ring chromosome 21 may be explained by hypogammaglobulinaemia and merit treatment with gammaglobulin. PMID- 9370910 TI - Benefits of newborn circumcision: is Europe ignoring medical evidence? PMID- 9370912 TI - Advances in radiology. PMID- 9370909 TI - Pemphigus foliaceus. AB - Pemphigus foliaceus is a skin disease in which antibodies against the cell surface of keratinocytes destroy the adhesion between epidermal cells, thereby producing blisters. It is a rare disease in childhood, and treatment guidelines for juvenile pemphigus foliaceus are lacking. An 8 year old boy with pemphigus foliaceus is described. He did not respond to topical steroids, and the condition flared up when high dose oral steroids were tapered. The lesions resolved completely in four weeks on dapsone, which was maintained for nine months with no major adverse effects, except for a moderate increase of the methaemoglobin concentration at the outset of treatment. There has been no evidence of disease reactivation in more than nine months of follow up since dapsone withdrawal. PMID- 9370911 TI - Antineutrophil cytoplasm antibodies and vasculitis. PMID- 9370913 TI - Paediatric bronchoscopy. PMID- 9370914 TI - Byler's syndrome. PMID- 9370915 TI - Intestinal neuronal dysplasia associated with cystic fibrosis. PMID- 9370917 TI - Vaccination with recombinant vaccinia viruses protects mice against Mycobacterium tuberculosis infection. AB - A number of subunit-based vaccine candidates have recently begun to erode the exclusive position of Mycobacterium bovis bacillus Calmette-Guerin (BCG), which gives unpredictable and highly variable protection against tuberculosis. In this paper we investigated the protective capacity of the 19,000 MW and 38,000 MW glyco-lipoproteins of M. tuberculosis expressed by recombinant vaccinia viruses in a mouse Mycobacterium tuberculosis infection model. Both proteins were expressed at high levels by recombinant vaccinia-infected cells. In addition, two inoculations of C57B1/6 mice with either recombinant vaccinia virus significantly reduced the bacterial counts in the lungs of M. tuberculosis H37Rv-infected mice, when compared with the group infected with control virus. This is the first report of protection against tuberculous infection using recombinant vaccinia viruses with results that suggest that secreted glyco-lipoproteins in conjunction with the vaccinia vector represent suitable candidates for further vaccine related studies. PMID- 9370916 TI - Interleukin-10 rescues T cells from apoptotic cell death: association with an upregulation of Bcl-2. AB - We demonstrate that interleukin-10 (IL-10) can inhibit T-cell apoptosis. T cells, within a PBMC (peripheral blood mononuclear cell) population, were stimulated via the T-cell receptor and grown in the presence of IL-2. These cells had less apoptosis when in the continuous presence of IL-10, compared with cells grown in the absence of IL-10. Conversely, when stimulated and grown in the presence of neutralizing antibody of IL-10, there was an increase in T-cell apoptosis. The in vitro rescue from apoptotic cell death of other lymphoid cells, such as germinal centre B cells, has been shown by others to involve a Bcl-2 pathway. We therefore investigated whether IL-10 might affect the Bcl-2 expression on cultured T cells. By Western blotting we demonstrated that continuous exposure of IL-10 to T cells (within a PBMC population) enhanced the expression of Bcl-2. Furthermore, T cells protected from apoptotic cell death by IL-10 were indistinguishable from viable untreated cells in their ability to proliferate to either immobilized anti-CD3 or IL-2. Thus, we have shown that continuous culture of T cells in the presence of IL-10 will inhibit T-cell apoptosis because of, at least in part, the upregulation of Bcl-2, and this is associated with a normal proliferative function. PMID- 9370919 TI - An antibody specific for interleukin-6 reverses age-associated changes in spontaneous and induced cytokine production in mice. AB - A number of quantitative and qualitative changes in the pattern of cytokine production have been reported to accompany the process of ageing in laboratory animals and in human populations, including an increase in serum levels of interleukin-1 (IL-1) and IL-6, as well as increased concanavalin A (ConA) stimulated production of IL-4, IL-10 and transforming growth factor-beta (TGF beta), and decreased production of IL-2 from cultured spleen cells. Increased IL 1 and IL-6 production is a feature of splenic adherent cells and peritoneal exudate cells taken from aged mice and stimulated with lipopolysaccharide in vitro. We have asked whether the altered production of lymphocyte-derived cytokines (IL-4, IL-2, TGF-beta) is itself a function of a primary alteration in IL-1/IL-6 production (from macrophage/monocytes) by infusing monoclonal antibodies to these cytokines prior to harvesting cells from aged mice and stimulating the cells in vitro. Anti-IL-6, but not anti-IL-1, reversed the age associated alteration in lymphocyte cytokine production. The general pattern of cytokine production in aged mice is of a type-2 cytokine type, and thus these data are consistent with the idea that increased production of IL-6 in aged animals is causally implicated in this age-associated polarization to type-2 cytokine production. PMID- 9370918 TI - Regulation of cytokine production by human Th0 cells following stimulation with peptide analogues: differential expression of TGF-beta in activation and anergy. AB - The different biological activities of T-cell-derived cytokines and their level of production influences the qualitative nature of immune responses and, in certain forms of T-cell tolerance, the lack of antigen responsiveness is associated with the production of transforming growth factor-beta (TGF-beta) and interleukin-4 (IL-4). In this study we have investigated the effects of T-cell receptor (TCR) ligation with peptide analogues and the native peptide, in the presence and absence of costimulation, on cytokine production by human T-helper type 0 (Th0) cells reactive with influenza virus haemagglutinin (HA) peptide (HA306-318) and restricted by HLA-DRB1*0101. We observed that resting Th0 cells constitutively produced TGF-beta, but when stimulated with peptide and antigen presenting cells (APC) under conditions that induce clonal expansion, TGF-beta secretion was abrogated. Furthermore, exposure of the T cells to the wild-type HA peptide under conditions that induce T-cell anergy resulted in the secretion of TGF-beta, and subsequent antigenic rechallenge was unable to override this signal and down-regulate TGF-beta production. Stimulation with altered TCR ligands that failed to induce proliferation also resulted in marked production of TGF-beta, although in many instances the levels were less than those observed in the total absence of antigen, suggesting that partial signalling has occurred. Although in general, there was a direct positive correlation between proliferation and the production of IL-2, IL-4 and interferon-gamma (IFN-gamma) following stimulation with certain analogues, the production of selected cytokines was dissociated. PMID- 9370920 TI - The role of interleukin-4 in ultraviolet B light-induced immunosuppression. AB - Prolonged exposure to ultraviolet light (UV) is known to lead to premature skin ageing, increased incidence of cataract and a high risk of developing skin cancers. UV-B irradiation, even if given as a single suberythemal dose, suppresses some immune responses, possibly reducing the production of T helper (Th) 1 cytokines [interleukin (IL)-2 and interferon-gamma] and augmenting Th2 cytokines (IL-4, IL-5 and IL-10) in mice. We investigated the role of IL-4 in UV B induced immunomodulation using IL-4 knockout (IL-4 -/-) mice and the parent strain Bb129. Suberythemal UV-B irradiation (1440 J/m2) led to a reduction in the density and antigen presenting ability of Langerhans' cells in the epidermis of both normal and IL-4 -/- mice. Exposure also induced an accumulation of CD4+ and CD8+ lymphocytes as well as dendritic cells in the lymph nodes draining the irradiated site in both strains. The proliferation of lymph node cells in response to the mitogen concanavalin A was enhanced in the IL-4 -/- mice compared with the parent strain. Following UV-B exposure, this proliferation was increased in lymph node cells of parent mice but was significantly suppressed in the IL-4 /- mice. The contact hypersensitivity (CH) response to oxazolone was suppressed to the same extent by UV-B irradiation in both strains. In the parent mice, infected with herpes simplex virus (HSV) following UV-B exposure and challenged subsequently with inactivated virus, the delayed hypersensitivity (DH) response was suppressed by about 50% compared with unirradiated mice; no such suppression in DH occurred in irradiated IL-4 -/- mice infected with HSV. Thus, IL-4 may be an important mediator of the UV-B-induced suppression in DH but not in CH, where other cytokines may be involved or may compensate for the lack of IL-4. PMID- 9370921 TI - p56lck is not essential for the T-cell response to allo-MHC antigens. AB - In mice lacking the src family protein tyrosine kinase, p 56lck (lck -/-), a greatly reduced number of peripheral T cells is observed due to a profound blockage of the thymocyte development. The peripheral T cells in lck -/- mice exhibit proliferative response after T-cell receptor (TCR)-crosslinking, but can not respond to viral antigens. In this report, we examined the allo-responses of peripheral T cells in the lck -/- mice and the following results were thus obtained. (1) After an intravenous injection of fully allogeneic [allo-major histocompatability complex (MHC)] spleen cells, an increase of interleukin (IL) 2R alpha+ cells was observed in both the CD4+ or CD8+ peripheral T cells of the lck -/- mice and the increase was similar to those in the lck +/+ littermate, with only a somewhat delayed and prolonged time kinetics observed in the CD4+ T cells of the lck -/- mice. (2) the lck -/- mice rejected the fully allogeneic trunk skin grafts several days later than the lck +/+ mice, but did not reject the minor allogeneic grafts. (3) The peripheral T cells of the graft-rejected lck -/- mice exhibited a weaker but significantly proliferative response, while the cytotoxic T lymphocyte (CTL) activities to allo-MHC antigens in vitro were comparable to those in lck +/+ mice. While the response to the minor allo antigens was shown by the peripheral T cells in the lck +/+ mice with minor allogeneic skin grafts but not by those in the lck -/- mice with the grafts. These results thus suggest that p56lck is not essential for peripheral T cells to both respond and exhibit effector functions to allo-MHC antigens. PMID- 9370922 TI - A multimeric form of soluble recombinant sheep LFA-3 (CD58) inhibits human T-cell proliferation. AB - The rosetting of T cells by sheep erythrocytes is mediated through the interaction of the CD2 molecule on T cells with T11TS, a molecule on sheep erythrocytes homologous to lymphocyte function-associated antigen-3 (LFA-3, CD58). We cloned a T11TS cDNA from sheep leucocyte mRNA which encodes a soluble molecule comprising the distal D1 and the D2 extracellular domains, but not the transmembrane domain. cDNA for this soluble D1 + D2 form of sheep LFA-3 (sLFA-3) was expressed in Escherichia coli and the properties of the purified recombinant protein were assessed by inhibition of T-cell rosette formation. sLFA-3 inhibited rosette formation, but its activity was low, 50% inhibition occurring at 25 micrograms/ml, consistent with the observed low binding avidity of fluorescein isothiocyanate (FITC)-labelled sLFA-3, sLFA-3 was made multimeric to increase its affinity, by crosslinking biotinylated sLFA-3 to streptavidin-biotinylated dextran complexes. The binding of crosslinked sLFA-3 multimers, tested by fluorescence-activated cell sorting (FACS) analysis, was significantly increased compared to sLFA-3 monomers. Competition with monoclonal antibodies demonstrated that multimeric sLFA-3 bound to the T11(1) epitope on CD2. The multimeric form of sLFA-3 was significantly more potent than the monomer in inhibiting proliferation of human T cells in response to purified protein derivative (PPD), tetanus toxoid (TT) or allogeneic cells. Multimeric sLFA-3 might, therefore, have potential as an immunotherapeutic agent to inhibit and/or anergize antigen-specific T-cell responses. PMID- 9370923 TI - Differential expression of CD8 epitopes amongst porcine CD8-positive functional lymphocyte subsets. AB - The swine is a useful model for immunobiological studies as it has a highly heterogeneous lymphocyte pool, containing several subsets not easily accessible in humans and rodents. In particular, the CD8-positive (CD8+) cells contain a variety of lymphocyte subsets, such as alpha beta-T cells, gamma delta-T cells, CD4 CD8 double-positive (DP) cells and natural killer (NK) cells. In order to define these subsets further, we have selected four monoclonal antibodies (mAb) with differential reactivity on CD8+ cells. Thus, mAb CD8.1 (PPT20) bound to CD8hi and CD8lo subpopulations in a similar way to the conventional anti-CD8. The mAb CD8.2 (PPT21), though binding to all of the CD8+ cells, reacted preferably with CD8hi. Two other mAb, CD8.3 (PPT22) and CD8.4 (PPT23), were specific for CD8hi alpha beta-T-cell subpopulation. These results, complemented by immunoprecipitation, co-modulation and enzyme-linked immunosorbent assay experiments, suggest that CD8.1 and CD8.2 react putatively with the CD8 alpha chain and CD8.3 and CD8.4 with the CD8 beta-chain. Tissue distribution studies revealed that CD8+ thymocytes and peripheral CD8hi alpha beta-T cells expressed both putative CD8 alpha- and beta-chains while peripheral CD4+ CD8+ alpha beta-T cells, CD8lo gamma delta-T cells and NK cells expressed only putative CD8 alpha chain. Functional studies indicated that the CD8hi alpha beta-T and CD8lo gamma delta-T cells were effector cells in the CD3-redirected cytotoxicity. PMID- 9370924 TI - Expression of major histocompatibility complex antigens on mouse brain microvascular endothelial cells in relation to susceptibility to cerebral malaria. AB - The physiopathology of experimental cerebral malaria (CM), an acute neurological complication of Plasmodium berghei ANKA (PbA) infection, involves interferon gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha), two cytokines that are known to modulate major histocompatibility complex (MHC) molecule expression. The aim of this study was to evaluate whether the genetic susceptibility to CM is related to the constitutive or IFN-gamma-induced expression of MHC molecules on brain microvessels. To this end, brain microvascular endothelial cells (B-MVEC) were isolated from CM-susceptible (CM-S, CBA/J) and resistant (CM-R, BALB/c) mice. By flow cytometry, we found that less than 5% of CM-S B-MVEC constitutively expressed MHC class I molecules, in contrast to up to 90% of CM-R B-MVEC. Upon stimulation with IFN-gamma, the percentage of positive cells for MHC class I molecules in CM-S B-MVEC became comparable to CM-R B-MVEC, but a higher fluorescence intensity existed on CM-S B MVEC compared with CM-R B-MVEC. MHC class II molecules were not constitutively expressed on B-MVEC from either strain. IFN-gamma-induced expression of MHC class II (I-A, I-E) molecules was significantly higher in CM-S than CM-R B-MVEC both in percentage of positive cells and fluorescence intensity. These data demonstrate that absent or low MHC class I and higher inducibility of MHC class II expression on B-MVEC are associated with the genetic susceptibility to CM. PMID- 9370925 TI - Interferon-gamma receptor-deficient mice exhibit impaired gut mucosal immune responses but intact oral tolerance. AB - Interferon-gamma (IFN-gamma) receptor knock-out (IFN-gamma R -/-) mice were used to analyse the role of IFN-gamma in mucosal immune responses following oral immunization. We found that the IFN-gamma R -/- mice demonstrated 50% reduced spot-forming cell (SFC) responses in the gut lamina propria and spleen after oral immunization with keyhold limpet haemocyanin (KLH) plus cholera toxin (CT) adjuvant. The IFN-gamma R -/- mice exhibited 10-fold reduced total serum KLH specific antibody levels compared with wild-type mice after oral immunization, while after intravenous immunization, no such difference was seen, suggesting a selective impairment of mucosal immune responses. Moreover, oral immunizations resulted in impaired interleukin-4 (IL-4), IL-10 and IFN-gamma production by spleen T cells from IFN-gamma R -/- mice, indicating that no reciprocal up regulation of Th2-activities had occurred despite the lack of IFN-gamma R function. No reduction in Th1 or Th2 cytokines was observed following systemic immunizations. Despite potentially strong modulating effects of IFN-gamma on epithelial cell IgA transcytosis and electrolyte barrier functions, CT-immunized IFN-gamma R -/- mice demonstrated unaltered protection against CT in ligated intestinal loops together with normal anti-CT IgA and total IgA levels in gut lavage. Oral feeding with KLH followed by parenteral immunization resulted in strongly suppressed SFC numbers and reduced cell-mediated immunity in both wild type and IFN-gamma R -/- mice. CT-adjuvant abrogated induction of oral tolerance in both IFN-gamma R -/- and wild-type mice. Collectively, our data argue that the two major response patterns induced by oral administration of protein antigen, i.e. active IgA immunity and oral tolerance, are differently regulated. Thus, IFN gamma R -/- mice have impaired mucosal immune responses while induction of oral tolerance appears to be unaffected by the lack of IFN-gamma functions. PMID- 9370926 TI - Expression of the neonatal Fc receptor, FcRn, on human intestinal epithelial cells. AB - Maternal IgG is transferred to the suckling mouse and rat through a major histocompatibility complex (MHC) class I-related Fc receptor (FcRn) on the brush border of the proximal small intestine. We have previously described a site on the epithelial surface of the human fetal intestine with IgG binding characteristics similar to FcRn. We report here the identification by reverse transcriptase polymerase chain reaction amplification and sequencing of the human orthologue of rat and mouse FcRn in tissue obtained from human fetal and adult intestine. FcRn protein was detected in adult human intestine by western blot. Immunohistochemical studies of sections of human intestine show that the FcRn is localized mostly to the epithelial cells, where it is in the apical region. These data suggest that the binding of IgG previously seen in the fetal intestine is due to the presence of FcRn. Potential roles for this MHC class I-like Fc receptor in the human intestine include the transfer of passive immunity, induction of oral tolerance, and immunosurveillance. PMID- 9370927 TI - TAK-603 selectively suppresses Th1-type cytokine production and inhibits the progression of adjuvant arthritis. AB - We have shown that TAK-603, a new anti-rheumatic drug, is more effective in animal models in which cellular immunity plays a central role. Here, we studied the effect of the drug on Th1 cytokines, which are dominantly produced in this type of immune reaction, in an in vitro system and an in vivo model. We established Th1- and Th2-dominant T-cell lines, and studied the effect of TAK-603 on their cytokine production. Th1 cell lines were BALB/c mouse allo-reactive T cells and C57BL mouse mite antigen-reactive T cells, and the Th2 cell line was BALB/c mouse ovalbumin-reactive T cells. TAK-603 suppressed the production of Th1 cytokines [interferon-gamma (IFN-gamma) and interleukin-2 (IL-2)] and not that of Th2 cytokines (IL-4, IL-5) in these cell lines. Furthermore, selective suppression of Th1 cytokine production was also observed in the T-cell clones obtained from the ovalbumin-reactive T-cell line. To investigate the effect on cytokine production in animal models of arthritis, we analysed the expression of cytokine messenger RNA using reverse transcription-polymerase chain reaction. In adjuvant arthritis rats, Th1-dominant cytokine production was observed both in the arthritic joint and the spleen, and the time-course paralleled the progression of arthritis. On the other hand, in type-II collagen-induced arthritis, in which TAK-603 has little effect, Th1-dominant cytokine production was not observed and Th2 cytokines were shown to be more important. The adjuvant arthritis rats treated with TAK-603 (6.25 mg/kg/day, per os) showed significantly lower cytokine mRNA expression both locally and systemically. These data suggest that TAK-603 selectively suppresses Th1 cytokine production, which is consistent with its effect on cellular immunity in animal models. PMID- 9370928 TI - Regulation of experimental autoimmune orchitis by the presence or absence of testicular antigens during immunological development in SCID mice reconstituted with fetal liver cells. AB - Severe combined immunodeficient (SCID) mice were immunologically reconstituted by the transfer of fetal liver cells (FLC) of BALB/c mice (SCID-FLC mice). In peripheral blood (PB) of SCID-FLC mice, B and T cells started to appear 2 and 5 weeks, respectively, after the transfer of FLC, and had attained normal levels by 7 weeks. Orchidectomy and transplantation of testis under the kidney capsule were conducted at various stages of immunological maturation, and the induction of experimental autoimmune orchitis (EAO) was performed after immunological maturation in SCID-FLC mice. The experimental system was used to establish that the presence of testicular antigens in the early stage of immunological development influences the induction of EAO; grade of EAO was reduced in the presence of the antigens, and enhanced in their absence. In other words, the existence of self tissue antigens in the early stage of immunological development was essential for proper establishment of tolerance to the self tissue. These findings suggested that the SCID-FLC mouse is a suitable model with which to analyse the interaction between self antigens and cells of the developing immune system, which is otherwise observed only in the fetal or perinatal stage in experimental animals. PMID- 9370929 TI - Immunization with gastric H+/K(+)-ATPase induces a reversible autoimmune gastritis. AB - The gastric H+/K(+)-ATPase has been implicated as a major autoantigen in pernicious anaemia in humans and in thymectomy-induced autoimmune gastritis in mice. Here we have shown that autoimmune gastritis can be generated by direct immunization of non-thymectomized BALB/c mice with mouse gastric H+/K(+)-ATPase in complete Freund's adjuvant. The gastritis was characterized by infiltration of the gastric submucosa and mucosa with macrophages, CD4+ and CD8+ T cells, and B cells and by circulating autoantibodies to the H+/K(+)-ATPase. The mononuclear infiltrate within the gastric mucosa was accompanied by loss of parietal and zymogenic cells and accumulation of small immature epithelial cells. Splenocytes from gastritic mice adoptively transferred gastritis to naive recipients. Cessation of immunization resulted in decrease in autoantibody titre and regeneration of parietal and zymogenic cells. The results directly confirm that the gastric H+/K(+)-ATPase is the causative autoantigen in the genesis of autoimmune gastritis. Recovery of the lesion following cessation of immunization suggests that homeostatic mechanisms can reverse a destructive autoimmune process. PMID- 9370931 TI - The effects of monoclonal antibodies against iC3b receptors in mice with experimentally induced disseminated candidiasis. AB - CR3 (iC3b receptor), composed of CD11b/CD18, is a beta 2 integrin. A protein that shares antigenic and structural homology with the alpha-chain of CD11b/CD18 has been isolated from the surface of Candida albicans. This molecule is thought to be essential in the pathogenesis of disseminated candidiasis. To evaluate the effects of anti-iC3b receptor antibodies on adhesion between human dermal microvascular endothelial cells (HDMEC) and C. albicans, and in treatment of candidal infection, a binding assay of C. albicans to cultured HDMEC was performed in vitro. An anti-iC3b receptor-specific monoclonal antibody was administered to mice infected with C. albicans. The mice were monitored for mortality and renal involvement by culture and histopathological findings. Flow cytometric analysis demonstrated surface expression of iC3b receptor on C. albicans. The adherence of C. albicans to HDMEC was significantly decreased by treatment with anti-iC3b receptor antibodies. Anti-iC3b receptor antibodies significantly increased the survival time and rate while lowering the renal fungal burden. The iC3b receptors are involved in the adherence of C. albicans to vascular endothelial cells and are likely to be involved in the pathogenesis of disseminated candidiasis. The increased survival in mice infected with C. albicans after treatment with anti-iC3b receptor antibodies indicates that this modality may be beneficial for future development of a new therapy for candidiasis. PMID- 9370930 TI - Extracorporeal photochemotherapy restores Th1/Th2 imbalance in patients with early stage cutaneous T-cell lymphoma. AB - Extracorporeal photochemotherapy (ECP) has been shown to be a potent activator of peripheral blood macrophages because it causes a marked release of macrophage dependent proinflammatory cytokines, and it is therefore currently considered to be a safe and non-toxic immunomodulatory treatment. On this basis we studied the function of peripheral blood mononuclear cells (PBMC) in eight patients with early stage (Ib) cutaneous T-cell lymphoma (CTCL), before and 1 year after ECP, together with their clinical and histological responses. In particular we evaluated in vitro phytohaemagglutinin (PHA)-stimulated proliferation and production of interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) as well as lipopolysaccharide (LPS)-induced production of IL-12. Before treatment we observed that PBMC of patients produced significantly higher levels of IL-4 and lower levels of IFN-gamma and IL-12 than those of healthy control subjects. After 1 year of ECP, IL-4, IFN-gamma and IL-12 production no longer differed from that of control subjects. Moreover, we observed a good clinical result matched by histological response. Our data confirm that early-stage CTCL patients show a predominantly type-2 immune response that might be responsible for several immunological abnormalities found in this disease. We have demonstrated that ECP reverses the T-helper type 1/T-helper type 2 (Th1/Th2) imbalance and may therefore be considered an efficient biological response modifier. PMID- 9370932 TI - HIV-1-specific cell-mediated immune responses induced by DNA vaccination were enhanced by mannan-coated liposomes and inhibited by anti-interferon-gamma antibody. AB - The adjuvant effect of mannan-coated liposomes on human immunodeficiency virus type-1 (HIV-1) DNA vaccine and the mechanism of this enhancement were studied. Coating of cationic liposomes with mannan significantly enhanced the ability of this vaccine to induce an HIV-specific delayed-type hypersensitivity (DTH) response. HIV-specific cytotoxic T-cell (CTL) activity elicited by DNA vaccination was also significantly enhanced with the mannan-liposome cocktail. This mannan-liposome-mediated activity was greatly inhibited by in vivo injection of anti-interferon (IFN)-gamma antibody, which suggests that IFN-gamma plays an important role in this HIV-specific immune response. The results of both isotype specific antibody and cytokine analysis revealed that mannan-liposome-mediated DNA vaccination enhances Th1-mediated immunity. PMID- 9370933 TI - A nitric oxide-releasing reagent, S-nitroso-N-acetylpenicillamine, enhances the expression of superoxide dismutases mRNA in the murine macrophage cell line RAW264-7. AB - Murine interferon-gamma (IFN-gamma) stimulates the murine macrophage tumour cell line RAW264-7 to produce nitric oxide (NO). IFN-gamma induces expression of inducible NO synthase (iNOS), manganese superoxide dismutase (Mn-SOD) and copper zinc SOD (CuZn-SOD) in these cells. To investigate the mechanism of induction of SOD expression, we added S-nitroso-N-acetyl penicillamine (SNAP) to RAW264-7 cells. SNAP enhanced the expression of Mn-SOD and CuZn-SOD. These results suggest that when producing NO, RAW264-7 cells express SOD that might protect them from NO toxicity. PMID- 9370934 TI - GM-CSF increases the ability of cultured macrophages to support autologous CD4+ T cell proliferation in response to Dermatophagoides pteronyssinus and PPD antigen. AB - Previous studies have demonstrated an infiltration of monocytes and increased levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) in the asthmatic lung. To study the possible effects of this cytokine upon the differentiation and function of these newly recruited monocytes, we have developed a model in which monocytes isolated from human peripheral blood were differentiated into macrophages in serum in the presence or absence of GM-CSF. After 7 days, the macrophages increased in size and granularity, had increased phagocytic activity, and expressed various adhesion molecules, CD14 and major histocompatibility complex (MHC) class II. The effects of GM-CSF on antigen presentation by cultured macrophages on the antigen-specific proliferative response of CD4+ T cells to Dermatophagoides pteronyssinus or purified protein derivative of tuberculin and the mitogen phytohaemagglutinin was determined. CD4+ T-cell proliferation was reduced when either antigen was presented by macrophages cultured in serum alone, compared with the values obtained with freshly isolated monocytes. However, CD4+ cell proliferation was comparable to that observed with monocytes when antigen was presented by macrophages which had been pre-cultured with 50 U/ml GM-CSF. CD4+ T-cell proliferation to phytohaemagglutinin was similar when all three populations were used as accessory cells. High numbers of macrophages partially suppressed CD4+ T-cell proliferation in response to antigen presented by monocytes, but there was no significant difference between macrophages cultured in the presence or absence of GM-CSF. This data suggests that GM-CSF directs monocyte differentiation into macrophages with an antigen presenting, rather than a suppressive, phenotype. Elevated levels of GM-CSF in the asthmatic lung may therefore maintain recently recruited monocytes in an inflammatory and T-cell activating state. PMID- 9370935 TI - Macrophage migration inhibitory factor induces phagocytosis of foreign particles by macrophages in autocrine and paracrine fashion. AB - Exposure to foreign particles sometimes causes inflammatory reactions through production of cytokines and chemoattractants by phagocytic cells. In this study, we focused on macrophage migration inhibitory factor (MIF) to evaluate its pathophysiological role in the phagocytic process. Immunohistochemical analysis of human pseudosynovial tissues retrieved at revision of total hip arthroplasty showed that infiltrating mononuclear and multinuclear cells were positively stained by both an anti-CD68 antibody and anti-human MIF antibody. For in vitro study, MIF was released from murine macrophage-like cells (RAW 264.7) in response to phagocytosis of fluorescent-latex beads in a particle dose-dependent manner. Northern blot analysis showed marked elevation of the MIF mRNA level in the phagocytic macrophage-like cells. Moreover, pretreatment of RAW 264.7 cells with rat recombinant MIF increased the extent of phagocytosis by 1.6-fold compared with the control. Taken together, these results suggest that MIF plays an important role by activating macrophages in autocrine and paracrine fashion to phagocytose foreign particles. PMID- 9370937 TI - Identification of specific recognition molecules on murine mononuclear phagocytes and B lymphocytes for Vi capsular polysaccharide: modulation of MHC class II expression on stimulation with the polysaccharide. AB - Vi bacterial polysaccharide is a homopolymer of alpha 1-4 N-acetyl polygalacturonic acid with variable O-acetylation at position C-3 and forms a capsule around many bacteria. It has been referred to as the virulence factor of Salmonella typhi and is also a candidate vaccine against typhoid fever. The present study reports the interaction of this polysaccharide with murine mononuclear phagocytes and lymphocytes, and with human monocytes. Vi showed a dose-dependent binding to the murine monocyte cell lines WEHI-274.1 and J774. This binding was abrogated if the polysaccharide was deacetylated, suggesting involvement of acetyl groups in this interaction. Vi also bound to the murine B cell lymphoma line A20, to peritoneal exudate cells and to a lesser degree to spleen cells and thymocytes from BALB/c mice. The polysaccharide also interacted with the human histiocytic lymphoma line U937 but not with the human monocyte cell line THP-1. Stimulation with Vi led to up-regulation of surface major histocompatibility complex (MHC) class II expression on A20 cells. Immunoprecipitation of Vi-bound molecules from cell surface biotinylated A20 and WEHI-274.1 revealed two bands with MW of about 32,000 and 36,000. The study demonstrates that Vi capsular polysaccharide can interact with mononuclear phagocytes and lymphocytes through specific cell surface molecules and modulate MHC class II expression. PMID- 9370936 TI - Human cytomegalovirus infection up-regulates interleukin-8 gene expression and stimulates neutrophil transendothelial migration. AB - Virus-induced alterations in the cellular expression of chemokines may be important in directing the migration of specific leucocyte subsets to sites of infection, thereby playing a pivotal role in viral pathogenesis. We show here that cytomegalovirus (CMV) infection of human fibroblasts resulted in significantly increased expression of the C-X-C or alpha-chemokine interleukin-8 (IL-8), at both the mRNA and protein levels. Increased IL-8 production was seen following infection with the high passage laboratory CMV strains AD169, Towne, or Davis, as well as the low passage clinical CMV isolates Toledo or C1F. The increase in IL-8 production had functional consequences, as demonstrated by the ability of supernatants from CMV-infected fibroblasts to significantly enhance neutrophil transendothelial migration. The latter was independent of alterations in adhesion molecule expression on the endothelial cells, and was abrogated by neutralizing antibodies specific for IL-8. Direct infection of endothelium with the endothelial cell-tropic CMV strain C1FE, also resulted in enhanced neutrophil transendothelial migration. Neutrophils play an important role in the dissemination of CMV throughout the body, and thus CMV-induced neutrophil recruitment would be expected to enhance CMV dissemination. Increased production of chemokines in response to CMV infection could also disrupt the fine balance between a beneficial and a destructive immune response, thereby potentially contributing to pathology. PMID- 9370938 TI - Immunogenicity of bacterial carbohydrates: cholera toxin modulates the immune response against dextran B512. AB - Native dextran B512 is a T-cell-independent (TI) antigen. By conjugating low molecular weight (MW) dextran to protein, a T-cell-dependent (TD) response against dextran can be obtained. We have previously reported the effects of native dextran and two different protein-dextran conjugates on the immune system. While one type of conjugate induced an optimal TD response, the other conjugate ('suboptimal') evoked a response more similar to that induced by native dextran, i.e. with little immunoglobulin class switch and with a secondary response of similar magnitude to the primary response. In order to investigate if it was possible to augment the anti-dextran response we examined the effects of cholera toxin (CT) in our dextran model system. CT is a potent mucosal, as well as systemic, adjuvant with effects on T cells, B cells and antigen-presenting cells. We show that CT is a very efficient adjuvant for both the TD and TI forms of dextran. A major increase in IgM and IgG anti-dextran antibody production was detected after administration of CT together with the conjugates compared with a conventional alum adjuvant. The effect was most pronounced for the suboptimal TD conjugate. CT was also able partially to abrogate the unresponsiveness to dextran in the TI type 2 (TI-2) non-responder strain CBA/N. CT was also found to be a very potent adjuvant for native dextran, secondary IgM levels were enhanced eightfold by the co-administration of CT. Furthermore CTB-Dx, which is a conjugate of the non-toxic part of CT and low MW, non-immunogenic dextran, elicited an anti-dextran response in nude mice. Collectively, our data show that it is possible to improve the immunogenicity of both TD and TI forms of a carbohydrate by co-administration of CT. This is indicative of two components of the adjuvant effect, one could enhance antigen presentation and costimulation of T cells and the other could have a direct stimulatory effect on B cells. PMID- 9370939 TI - Basement membrane synthesis and degradation. AB - The biological importance of complex interactions between cells and extracellular matrix has become widely recognized. For normal epithelial cells, contact with the matrix is limited to the basement membrane. Our understanding of the composition and assembly of basement membranes is increasing, as is our understanding of the mechanisms by which synthesis and degradation of basement membranes are controlled. Basement membrane abnormalities may result from disease and may cause disease. Papers in this edition of the Journal of Pathology discuss changes in basement membrane composition in disease, and add yet another link to the many connections between basement membranes, fibrosis and the control of cell proliferation. PMID- 9370940 TI - Trefoil proteins: their role in normal and malignant cells. AB - The three human trefoil proteins pS2, human intestinal trefoil factor (hITF), and human spasmolytic polypeptide (hSP) are expressed principally in the mucosa of the gastrointestinal tract. They are also expressed in a variety of other normal tissues and tumours. This review discusses the pattern of expression of trefoil proteins in cancer, current views on the biological functions of trefoil proteins, and the way in which the expression of trefoil proteins may influence the behaviour of cancer cells. PMID- 9370941 TI - Quantitative changes in the glomerular basement membrane components in human membranous nephropathy. AB - In membranous nephropathy (MN), the glomerular basement membrane (GBM) is thickened due to accumulation of GBM material between and around the subepithelial immune deposits. Alterations in the GBM components in relation to subepithelial deposits and GBM thickening are not clearly defined. The GBM distribution of classical and novel [alpha 4(IV)] chains of type IV collagen, laminin, and fibronectin have been studied in seven patients with MN and in three normal controls by a quantitative immunogold technique. In normal kidneys, the labelling of type IV collagen or fibronectin was distributed predominantly along the endothelial side of the GBM; alpha 4(IV) was found in the lamina densa; and laminin was concentrated in the epithelial zone of the GBM (P < 0.01). In MN, there were increased immunogold densities for classical and novel type IV collagen chains, laminin, and fibronectin in the spikes of MN patients compared with controls (P < 0.05). Furthermore, gold particle labelling for the alpha 4(IV) collagen chain was increased in the middle zone (P < 0.01) and that for fibronectin was increased in the endothelial and middle zones of the GBM (P < 0.05) compared with normal controls. These findings suggest that subepithelial immune deposits stimulate glomerular epithelial cells (GEC), resulting in enhanced secretion of classical and novel type IV collagen chains, laminin, and fibronectin, forming spikes in MN; of these newly formed components, only novel type IV collagen appears to migrate towards the middle zone of the GBM, contributing to thickening of this zone. The results also suggest that fibronectin, possibly derived from the circulation, is related to thickening of the endothelial zone of the GBM, which in turn might be related to progressive glomerulosclerosis. PMID- 9370942 TI - A novel transcription factor is correlated with both glomerular proliferation and sclerosis in the rat renal ablation model. AB - Glomerular accumulation of the extracellular matrix (ECM) with subsequent sclerosis is a common finding in most progressive renal diseases. Recently MSW (Mouse South Western) protein was cloned by its ability to bind the bidirectional promoter of the collagen IV genes. This protein was also reported as the large subunit of the DNA replication complex A1, as well as the promoter binding protein of corticotropin-releasing hormone and the angiotensinogen gene. To investigate the mechanism of accumulation of the ECM as it relates to glomerular cellular events, the expression of MSW protein was studied in the remnant kidney model. Progressive expression of MSW protein was found in the glomerular sclerotic lesion at week 4 and at later time points after renal ablation. The expression of proliferating cell nuclear antigen (PCNA) and type IV collagen was also correlated with the expression of MSW protein by immunofluorescence. RNA dot blot analysis also showed that the expression of MSW mRNA was increased at week 7 in association with the augmented expression of type IV collagen. These results, taken together, suggest that MSW protein plays an important role in the regulation of type IV collagen gene expression in vivo and may contribute to glomerular cell proliferation and the development of glomerulosclerosis. PMID- 9370943 TI - Collagen-binding heat shock protein (HSP) 47 expression in anti-thymocyte serum (ATS)-induced glomerulonephritis. AB - An increased accumulation of extracellular matrix (ECM), predominantly collagens, is the main component of the expanded mesangial matrix in anti-thymocyte serum (ATS)-induced glomerulonephritis (GN). Heat shock protein (HSP) 47 is a collagen binding stress protein and has been shown to have a specific role in the intracellular processing of procollagen molecules. It is a collagen-specific molecular chaperone in various organs, but its role in the kidney in relation to matrix expansion is not yet known. This study was designed to assess whether increased ECM accumulation in ATS-induced GN is associated with HSP47. The expression of type I, type III and type IV collagens, with their molecular chaperone HSP47, was investigated in ATS-induced GN rat kidneys. Fifteen male Wistar rats were divided into two groups: ATS-induced GN rats (group I) and age matched controls (group II). GN was induced by injecting a single dose of ATS (0.8 ml/100 g body weight). All the rats were killed on the third and tenth day of the experiment. In group I, 3 days after ATS injection, histological examination revealed a reduction in glomerular cell number with mesangiolysis. However, 10 days after ATS injection, histologically severe mesangial cell proliferation with expansion of the mesangial matrix was noted in group I rats. By semiquantitative analysis, compared with controls, increased type I, type III, and type IV collagen immunostaining was observed in the expanded mesangial matrix in ATS-induced GN (group I) rats on day 10. Immunoreactive HSP47 expression was weak in the intraglomerular cells and was occasionally seen in the interstitial cells in control kidneys. In contrast, strong immunostaining for HSP47 was noted in the glomeruli of the ATS-treated rat kidneys on day 10. In this study, there was a parallel increase of various collagens and their molecular chaperone HSP47 in the ATS-treated rat kidneys. Compared with controls, no significant difference in HSP47 expression was found in the ATS-treated rat kidneys without mesangial matrix expansion (3 days after ATS injection). It is concluded that overexpression of HSP47 might play a significant role in the excessive assembly of collagens and could subsequently contribute to the expansion of mesangial matrix found in ATS-treated rat kidneys. PMID- 9370945 TI - The association between tumour progression and vascularity in the oral mucosa. AB - Tumourigenesis in experimental models is associated with the formation of new blood vessels (angiogenesis). Recent studies have suggested that tumour angiogenic activity may be inferred in histological sections by measuring the density of the vasculature. The purpose of this study was to determine whether the transition from normal to dysplastic and neoplastic tissue in the oral mucosa is accompanied by quantitative or qualitative changes in the vascularity of the tissue, and how the estimate of vascularity is influenced by the vessel marker and method of assessment. A total of 100 specimens of normal oral mucosa, dysplastic lesions, and squamous cell carcinomas were examined. Sections were immunostained with the pan-endothelial antibodies to von Willebrand Factor (vWF) and CD31, or with an antibody to the alpha v beta 3 integrin, previously reported to be a marker of angiogenic vessels. Vascularity was quantitated by two different methods: highest microvascular density (h-MVD) and microvascular volume, as determined by point counting (MVV). The results showed that vascularity, measured by the MVV method using antibodies to either vWF or CD31, increased significantly (P < 0.0001) with disease progression from normal oral mucosa, through mild, moderate, and severe dysplasia to early and late carcinoma (76 paraffin-embedded tissues examined). In contrast, h-MVD did not discriminate between dysplastic lesions and carcinoma. A similar percentage of the total vessel volume (MVV) and density (h-MVD) were positive for alpha v beta 3 in 24 frozen tissues examined, including normal oral mucosa. It is concluded that there is a close association between vascularity and tumour progression in the oral mucosa. Morphometric analysis reflecting microvascular volume is more informative than the currently popular analysis of microvascular density. The expression of alpha v beta 3 in the vasculature of oral tissues does not necessarily reflect the presence of angiogenic vessels. PMID- 9370944 TI - Intestinal trefoil factor (TFF 3) and pS2 (TFF 1), but not spasmolytic polypeptide (TFF 2) mRNAs are co-expressed in normal, hyperplastic, and neoplastic human breast epithelium. AB - pS2-TFF 1 is expressed in breast cancers and has been investigated as a potential prognostic factor reflecting oestrogen dependence. The relationship to the expression of other trefoil peptides, human spasmolytic polypeptide (hSP-TFF 2) and intestinal trefoil factor (hITF/hPI.B-TFF 3) is documented here. Fifty-seven breast specimens were selected from surgical pathology archives and included five normal breasts (two lactating), seven benign proliferative lesions, 11 ductal carcinomas in situ (DCIS), three lobular carcinomas in situ (LCIS), 24 invasive ductal carcinomas (IDC), and seven invasive lobular carcinomas (ILC). The comparative distribution of trefoil mRNAs was assessed by in situ hybridization using 35S-labelled riboprobes and immunohistochemical staining for pS2-TFF 1 and hSP-TFF 2. pS2-TFF 1 and hITF/hPI.B-TFF 3 mRNA were focally present at low signal intensity in normal and benign breast. Both pS2-TFF 1 and hITF/hPI.B-TFF 3 were expressed in all DCIS, LCIS and ILC, and 21/24 IDC. Overall, expression patterns of pS2-TFF 1 and hITF/hPI.B-TFF 3 coincided, but hITF/hPI.B-TFF 3 mRNA was usually found in a greater proportion of cells. Expression of hSP-TFF 2 peptide or mRNA was not detected in any of these cases. MCF 7 breast carcinoma cells also expressed hITF/hPI.B-TFF 3 and pS2-TFF 1 mRNAs but not hSP-TFF 2. hITF/hPI.B-TFF 3 co-expression with pS2-TFF 1 may act as a prognostic factor, but also raises questions about the regulatory pathway for pS2-TFF 1 hITF/hPI.B-TFF 3. Trefoil factors have effects on cell motility and spreading in vitro, and co-expression of hITF/hPI.B-TFF 3 with pS2-TFF 1 could be functionally significant if they form a heterodimer or compete for receptor binding. Absence of hSP-TFF 2 expression may be of equal relevance to tumour cell biology. PMID- 9370947 TI - Increased cell proliferation activity and decreased cell death are associated with the emergence of hormone-refractory recurrent prostate cancer. AB - The tumour growth kinetics (cell proliferation and apoptosis) of ten hormone refractory locally recurrent prostate cancers were compared with their matched untreated primary tumour specimens. All recurrent tumours had a higher cell proliferation activity, as defined by Ki-67 immunohistochemistry, than corresponding primary tumours from the same patients. The mean cell proliferation activity in recurrences (13.5 +/- 3.8 per cent) was over two times higher (P < 0.0001) than that in primary tumours (5.5 +/- 2.4 per cent), suggesting that cell clones which progress during androgen withdrawal are actively stimulated to proliferate. The mean percentage of apoptotic cells, as estimated by the in situ end-labelling technique, was 5.4 +/- 4.7 per cent in untreated primary tumours, whereas it was 2.3 +/- 1.5 per cent in locally recurrent tumours (P = 0.05). In all but two cases, the apoptotic index was lower in recurrent than in corresponding primary tumours, suggesting that recurrent prostate carcinomas are able to avoid apoptosis in the androgen-deprived environment. In conclusion, the clinical progression of prostate cancer during androgen withdrawal is associated with increased cell proliferation and decreased apoptosis. PMID- 9370946 TI - Expression of vascular endothelial growth factor in lymphomas and Castleman's disease. AB - Vascular endothelial growth factor (VEGF) is one of the main angiogenic cytokines in human solid tumours and inhibition of VEGF-induced angiogenesis suppresses tumour growth. Some groups of malignant lymphoma, including peripheral T-cell lymphomas and Hodgkin's disease, are characterized by a conspicuous proliferation of small vessels. To test the hypothesis that VEGF may also be involved in the angiogenesis in lymphomas and other lesions of the lymphoid system, VEGF expression was analysed in tissues, employing in situ hybridization with a 35S labelled RNA probe specific for this cytokine. Significant expression of VEGF transcripts was observed in Hodgkin's disease and peripheral T-cell lymphomas, particularly of the angioimmunoblastic type. In contrast, expression of this cytokine was minimal or absent in follicle centre lymphoma and chronic lymphocytic leukemia of B-cell type. VEGF was mainly observed in reactive non lymphoid CD68-negative cells, which probably represent fibroblasts or myofibroblasts. In normal and ulcerated tonsils, VEGF was expressed in the squamous epithelium but only rarely found in the lymphoid tissue. Although infectious mononucleosis tonsils contained high numbers of VEGF-positive cells in the interfollicular zone, expression of this cytokine was not found in Epstein Barr virus (EBV)-infected cells, as determined by simultaneous in situ hybridization for VEGF and EBV-encoded small nuclear RNAs (EBER). In 5/8 cases of Castleman's disease, germinal centres containing small vessels also showed expression of VEGF, in contrast to normal tonsillar germinal centres which are devoid of both vessels and VEGF transcripts. It is concluded that VEGF may be involved in the induction of the angiogenesis of both peripheral T-cell lymphomas and Hodgkin's disease, but not in low-grade B-cell lymphomas. In contradistinction to solid tumours, in which this cytokine is commonly secreted by the tumour cells themselves, in malignant lymphoma VEGF is not a product of neoplastic cells. Vascularization of germinal centres in Castleman's disease may also be a consequence of abnormal local expression of VEGF. PMID- 9370948 TI - Telomerase activity and its inhibition in benign and malignant breast lesions. AB - Many types of human tumours and immortal cell lines have been demonstrated to exhibit telomerase activity with the recently formulated telomeric repeat amplification protocol (TRAP assay). However, a small proportion of undoubted tumour samples give a negative result and it has been postulated that, on occasion, the assay can be blocked by inhibitory factors in the cell or tissue extracts. To resolve this issue, a modified TRAP assay has been used to re examine 45 previously negative breast tissue specimens. Phenol--chloroform extraction of the sample after the telomerase extension reaction revealed the presence of polymerase chain reaction (PCR) inhibitory factors in tissue from 6 of 14 (43 per cent) breast biopsies of fibrocystic disease (FCD), 6 of 12 (50 per cent) fibroadenomas (FAs), none of five carcinomas in situ, and 1 of 13 (8 per cent) invasive carcinoma (CA) tissue specimens. These results demonstrated that the enzyme telomerase can be active in some benign lesions as well as in carcinomas of the breast. Specimens which still remained negative for telomerase in the above experiment were next assayed for the presence of biologically relevant inhibitors of the enzyme by mixing the extracts with confirmed positive samples. Extracts from 12 of 17 carcinoma specimens (all of five carcinomas in situ and 7 of 12 invasive carcinomas showed dose-dependent inhibitory activity against telomere extension, whereas no inhibition was observed in those of three of eight FCD and 2 of seven FAs. These results indicate that telomerase activity may be regulated by a balance between inhibitory factors and an activated enzyme. PMID- 9370949 TI - High-affinity monomeric 67-kD laminin receptors and prognosis in pancreatic endocrine tumours. AB - Cell-surface high-affinity monomeric 67-kD laminin receptors have been proposed to promote the invasion and metastasis of a variety of tumours, but there are, as yet, no data regarding the expression of these molecules in pancreatic endocrine tumours (PETs). The prognosis of these very rare tumours is problematic and the only irrefutable evidence of their malignancy still continues to be the occurrence of local invasion and metastases. In this retrospective investigation, 34 functioning and 48 non-functioning sporadic PETs were evaluated for the expression of the MLuC5 monoclonal antibody, which specifically recognizes the 67 kD laminin receptors. Laminin receptors were found in 42/82 cases (51 per cent) and their expression was associated with metastatic disease (P < 0.001), high proliferative activity expressed by a Ki-67 index above 5.0 per cent (P < 0.001), absence of progesterone receptors (P = 0.013), immunoreactivity for hormones other than insulin (P < 0.001), a tumour diameter more than 3.0 cm (P = 0.001), and a fatal clinical outcome (P < 0.001). Laminin receptors were also expressed by most metastatic foci and all intravascular emboli of tumour cells. Positivity for laminin receptors was associated with shorter survival in functioning (P = 0.026) and non-functioning (P = 0.042) tumours, as well as in the whole series of pancreatic endocrine tumours (P < 0.001). On multivariate analysis, laminin receptor expression was not an independent prognostic factor, while a Ki-67 index above 5.0 per cent was the most powerful predictor of survival. However, the association of laminin receptor expression and Ki-67 index could identify a group of malignant PETs with low proliferative activity characterized by an intermediate prognosis. In conclusion, these data suggest that monomeric laminin receptors may play a role in the invasion and metastasis of PETs and that their expression may be an additional prognostic factor, along with proliferative activity. PMID- 9370950 TI - Epidermal Langerhans' cells in children with primary T-cell immune deficiencies. AB - Dendritic cells are the major antigen-presenting cells, especially for naive T lymphocytes; it is conceivable therefore that their absence or dysfunction may induce an immune deficiency (ID). Few data are available, however, concerning dendritic cells in human primary ID. Langerhans' cells (LC) are intraepidermal dendritic cells which express specific markers and may therefore be studied by immunohistochemistry on paraffin-embedded skin samples. Skin samples of nine children with primary ID were studied and compared with five age-matched controls. LC were present within the epidermis of two children with X-linked severe combined ID, a condition related to the lack of the common gamma-chain of interleukin-2 (IL-2), IL-4, IL-7, IL-9, and IL-15 receptors. LC were also present in skin samples of a child with Omenn syndrome and in three children with combined ID. By contrast, no LC were detected in the skin samples of two children with alymphocytosis and of a child with reticular dysgenesis, a condition characterized by the absence of peripheral blood leukocytes. PMID- 9370951 TI - Expression of Fas ligand mRNA in germinal centres of the human tonsil. AB - Fas ligand (FasL), a cell surface molecule belonging to the tumour necrosis family, induces apoptosis through its receptor, Fas antigen (Fas). Germinal centre B cells strongly express Fas, but the role of the Fas-FasL system in B cell selection in the germinal centre remains unclear. In the present study, FasL mRNA in the tonsils was examined by RNA in situ hybridization. FasL mRNA was detected in the lymphocytes of both germinal centres and interfollicular areas, but much more intensively in the former. The distribution of cells strongly expressing FasL mRNA in the germinal centres was quite similar to that of CD45RO positive T cells. Immunohistochemically, however, most of the germinal centre cells were positive for FasL. Flow cytometric analysis demonstrated that FasL positive cells of the tonsils included not only CD3-positive/CD45RO-positive T cells, but also CD19-positive B cells. This finding therefore suggests either that germinal centre B cells can produce FasL, although the level of mRNA was equivocal, or that the soluble form of FasL may be released from FasL-positive T cells in the germinal centres and then bind to Fas-positive germinal centre B cells. Thus, the Fas-FasL system may participate in the positive selection of B cells. PMID- 9370952 TI - Age-related changes in the temporal and spatial distributions of fibrillin and elastin mRNAs and proteins in acute cutaneous wounds of healthy humans. AB - Elasticity and resilience of the skin are determined largely by the elastin framework, whose microfibrillar scaffold is composed of fibrillin. To date, the spatial and temporal patterns of expression of human elastin and fibrillin during would healing have not been described. Ninety healthy human subjects underwent 4 mm cutaneous punch biopsy wounds from the upper inner arm, which were re-excised from day 3 to 3 months post-wounding. There were marked changes in the patterns of distribution and the amounts of elastin and fibrillin in sun-protected skin with ageing. However, there were no major age-related differences in the mRNA levels for elastin, fibrillin-1 and fibrillin-2 using in situ hybridization. Elastin and fibrillin appeared in greatest amounts in the wounds of the elderly, particularly in females. A regenerative pattern of elastin and fibrillin arcades at the dermo-epidermal junction was observed in the wounds of aged subjects. mRNA expression of elastin was greatest in the wounds of the aged (from day 3 to day 14 post-wounding) with a similar spatial and temporal pattern to fibrillin-1 expression; this suggests that fibrillin-1 is the major contributor to dermal elastic fibre construction during wound repair. Fibrillin-2 was expressed only in the wounds of the aged and expression was confined to areas proximal to dermal blood vessels. The clear-cut differences in the localization of the two members of the fibrillin family suggest that these have well-defined roles in normal skin and wound tissue. In summary, these data indicate that ageing is associated with increased expression of fibrillin and elastin during acute wound healing and concomitant restoration of the papillary dermal architecture with an improved quality of scarring. PMID- 9370953 TI - Gene expression and synthesis of fibronectin isoforms in rat hepatic stellate cells. Comparison with liver parenchymal cells and skin fibroblasts. AB - Fibronectins are multifunctional glycoproteins that are important components of the extracellular matrix in normal and fibrotic liver. Multiple fibronectin isoforms are generated from a single gene by alternative splicing of the primary transcript at the domains EIIIA, EIIIB, and V. The aim of this study was to investigate the fibronectin isoforms expressed by activated hepatic stellate cells, the most important connective tissue-producing cells in injured liver. Hepatocytes and skin fibroblasts were also studied for comparison. Activation of hepatic stellate cells in vivo was induced by injecting CCl4 twice weekly for 3 weeks. Activation in vitro was achieved by culturing cells on plastic. The level of activation was evaluated by alpha-smooth muscle actin immunocytochemistry. Steady-state levels of fibronectin isoform messenger RNA were examined by Northern hybridization analysis using specific cDNA probes for the EIIIA, EIIIB, and V domains. The de novo synthesis of fibronectin isoforms was examined by metabolic labelling and immunoprecipitation using domain-specific monoclonal antibodies. Fibronectin transcripts were not detectable in freshly isolated hepatic stellate cells from normal liver. Cultured hepatic stellate cells, as well as skin fibroblasts, expressed EIIIA+, EIIIB+, and V95+ transcripts. They were detectable as early as day 3 and increased with time in culture. At 3 days in culture, more than 90 per cent of stellate cells were alpha-smooth muscle actin-positive. In vivo activated hepatic stellate cells expressed EIIIA+ and V95+ transcripts; EIIIB+ fibronectin mRNA was absent. Less than 20 per cent of in vivo activated stellate cells expressed alpha-smooth muscle actin. Freshly isolated parenchymal cells from normal liver as well as from CCl4-treated liver expressed V95+ transcripts, but were negative for EIIIA or EIIIB fibronectin mRNA. Immunoprecipitation results were in accordance with Northern hybridization analysis. Hepatic stellate cells in culture synthesized and secreted fibronectin molecules that contained EIIIA, EIIIB, and V fragments. Our results indicate that hepatic stellate cells synthesize and secrete fibronectin isoforms that are distinct from those of parenchymal cells. PMID- 9370954 TI - Identification of host and donor cells in porcine homograft heart valve explants by fluorescence in situ hybridization. AB - The pathogenesis of the primary tissue degeneration that limits the life-span of aortic and pulmonary homografts has still not been revealed. Histopathological studies on homograft explants have not given definitive insight into the eventual fate of donor cells, nor have they demonstrated the assumed importance of host cell ingrowth into the graft tissue. In this experimental study, fluorescence in situ hybridization (FISH) is introduced as a new approach to examine the distribution of host and donor cells in homograft explants. Aortic valve replacement was performed with a cryopreserved porcine aortic homograft in three pigs; donor and recipient were of opposite sex. After 4 months, the grafts were explanted and examined by FISH using a biotinylated porcine Y-chromosome-specific library probe. Following probe detection with FITC-conjugated avidin, a clear distinction could be made between cells of host and donor origin without distorting the histological integrity of the explants. There was ingrowth of donor cells into the graft aortic wall and into the valve leaflet, to some extent. In all explants, remaining donor cells were present, though decreased in number. The introduction of FISH in homograft heart valve research provides a powerful tool to study the fate of recipient and donor cellular elements in situ, and may therefore contribute to a better understanding of the histopathological processes that take place in transplanted homograft valves. PMID- 9370955 TI - Expression of cytokine mRNAs in murine hearts with acute myocarditis caused by coxsackievirus b3. AB - In murine acute viral myocarditis, natural killer (NK) cells infiltrate the heart first, followed by activated T-cells, which play an important role in the pathogenesis of the myocardial damage. Because of their multipotential effects, cytokines are thought to play a role in the induction and development of these immune processes. To clarify in more detail the precise mechanism of the cytokine networks involved, the expression of various cytokine mRNAs has been investigated in myocardial cells infected with Coxsackievirus B3 (CVB3) in vivo and in vitro by a semiquantitative polymerase chain reaction (PCR) method. Interleukin (IL)-1 alpha, IL-1 beta, IL-6, tumour necrosis factor (TNF)-alpha, and TNF-beta were expressed almost throughout the early phase of virus infection with some variations. IL-2, IL-3, IL-4, IL-10, interferon (IFN)-gamma, granulocyte/macrophage colony stimulating factor (GM-CSF), and IL-2 receptor (IL 2R) were mainly expressed by the infiltrating cells. TNF-alpha, TNF-beta, and IL 1 beta were also expressed partly by the infiltrating cells. T-helper (Th)1 related cytokines (IL-2, IFN-gamma, and TNF-beta) were more strongly expressed than Th2-related cytokines (IL-4 and IL-10) in vivo, indicating that the Th cells which infiltrated the heart and mediated the immune responses in the early phase of acute myocarditis were mainly of Th1-type. PMID- 9370956 TI - The effects of maternal protein deprivation on the fetal rat pancreas: major structural changes and their recuperation. AB - There is evidence that low birth weight and poor growth in early life cause a long-term predisposition to non-insulin-dependent diabetes. Morphological changes were assessed in fetal rat pancreas subjected to both pre- and post-natal maternal protein deprivation (LP). Further groups were subjected to purely prenatal maternal protein deprivation (preLP) and purely postnatal maternal protein deprivation (postLP), as well as a control group. The results show that the LP and postLP groups had fewer but larger islets than the control group, while the preLP group had more numerous, smaller islets. All three low protein groups had more irregularly shaped islets than the control group. There was a reduction in the amount of beta cells within each islet in all three protein deprived groups. The LP and postLP groups showed a reduction in the percentage of islet tissue and beta cells per pancreas, but the percentage of islet tissue expressed per unit body weight was similar in all four groups. These results show that in maternal protein deprivation, homeostatic mechanisms ensure a constant amount of pancreatic endocrine tissue per unit of body weight. However, there remain major structural changes in the size, shape, and composition of the islets. These results support the theory that early development profoundly affects the structure of the pancreas and may play a role in the later development of adult diseases, such as non-insulin-dependent diabetes mellitus. PMID- 9370957 TI - Antigen retrieval techniques in immunohistochemistry: comparison of different methods. AB - Routine sections of normal and pathological samples fixed in 10 per cent buffered formalin or B5, including EDTA-decalcified bone-marrow biopsies, were tested with 61 antibodies following heating in three different fluids: 0.01 M citrate buffer (pH 6.0), 0.1 M Tris-HCl (pH 8.0), and 1 mM EDTA-NaOH solution (pH 8.0). The sections underwent either three cycles of microwave treatment (5 min each) or pressure cooking for 1-2 min. The alkaline phosphatase/anti-alkaline phosphatase (APAAP) technique was used as the standard detection method; with 16 antibodies a slightly modified streptavidin-biotin complex (SABC)-immunoperoxidase technique was applied in parallel. The results obtained were compared with those observed without any antigen retrieval (AR), or following section digestion with 0.05 per cent protease XIV at 37 degrees C for 5 min. Chess-board titration tests showed that all antibodies but one profited by AR. Protease XIV digestion represented the gold standard for five antibodies, while 55 produced optimal results following the application of heat-based AR. By comparison with the other fluids, EDTA appeared to be superior in terms of both staining intensity and the number of marked cells. These results were independent of tissue processing, immunohistochemical approach, and heating device. Pressure cooking was found to be more convenient on practical grounds, as it allowed the simultaneous handling of a large number of slides and a time saving of 1 min 30 s, representing the proper time for the treatment. PMID- 9370958 TI - Do neutrophils contribute to the clearance of injured cardiomyocytes in reperfusion injury? PMID- 9370959 TI - Interpretation of the signal patterns produced by NISH in cervical neoplasia harbouring HPV. PMID- 9370960 TI - Changes in gonadotrophin-releasing hormone (GnRH-I) in the pre-optic area and median eminence of starlings (Sturnus vulgaris) during the recovery of photosensitivity and during photostimulation. AB - Changes in GnRH-I in the pre-optic (POA) and medio-basal (MBH) areas of the hypothalamus and in pituitary and plasma LH were measured in starlings (Sturnus vulgaris) during the recovery of photosensitivity under short days, and following photostimulation at various times during the recovery of photosensitivity. During exposure to short days there was a significant increase in GnRH-I in the POA, with the first detectable increase after only 10 days. There was no increase in GnRH-I in the MBH or in pituitary or plasma LH. In birds photostimulated after 10 short days, there was an increase in GnRH-I in the POA, but this was no greater than that in birds remaining under short days. There was no increase in GnRH-I in the MBH or in plasma LH. Photostimulation after 20 short days caused an immediate increase in GnRH-I in the POA, delayed increase in GnRH-I in the MBH, but no increase in plasma LH. Photostimulation after 30 short days caused an immediate increase in GNRH-I in the POA and the MBH and in plasma LH. The results show that the recovery of photosensitivity is gradual; the first measurable change occurs in the POA, consistent with photosensitivity being due to renewed GnRH-I synthesis. The effects of photostimulation increase, both in magnitude and in terms of how far 'downstream' of the POA changes are apparent, as photosensitivity is gradually restored. The results support the hypothesis that daylength has a dual role, controlling both synthesis and secretion of GnRH. PMID- 9370961 TI - Endometrial expression of mRNA encoding insulin-like growth factors I and II and IGF-binding proteins 1 and 2 in early pregnant ewes. AB - The temporal variations in endometrial expression of mRNA encoding insulin-like growth factor I (IGF-I) and IGF-II, and insulin-like growth factor-binding protein 1 (IGFBP-1) and IGFBP-2 were investigated between oestrus and day 20 of pregnancy in ewes. Northern blot analysis of endometrial total RNA revealed major transcripts for IGF-I (7.1 kb), IGF-II (5.8 kb), IGFBP-1 (1.3 kb) and IGFBP-2 (1.7 kb). Some minor transcripts for IGF-II were also detected. The low endometrial expression of mRNA encoding IGF-I at day 15 of pregnancy was used as the reference point for time comparison for expression of mRNA encoding IGF-I, IGF-II and IGFBP-2. The mRNA encoding IGFBP-1 was not quantitated since the gene was expressed only on day 15 of pregnancy. Endometrial expression of mRNA encoding IGF-I was increased (P < 0.05) at oestrus and on day 8 of pregnancy relative to expression on day 15, whereas expression of mRNA encoding IGFBP-2 was decreased (P < 0.05). The major IGF-II transcript was unaffected by day of pregnancy. The temporal variation of the expression of mRNAs encoding IGF-I and IGFBP-2 suggests a role for these factors in the uterine environment during early pregnancy in ewes coinciding with rapid development of the embryo and growth of the uterus in preparation for implantation. PMID- 9370962 TI - Protein kinase C dependent and independent mechanisms controlling rat trophoblast cell DNA synthesis and differentiation. AB - Trophoblast giant cells are the steroidogenic cells of the rat placenta. In this study, the role of protein kinase C signalling pathways in the control of DNA synthesis and differentiation-dependent progesterone biosynthesis by trophoblast cells were investigated. Rcho-1 trophoblast cells, derived from a rat choriocarcinoma, can be experimentally manipulated to proliferate or differentiate and provide a useful model for studying trophoblast giant cell endocrine differentiation. The role of protein kinase C signal transduction was examined through the treatment of Rcho-1 trophoblast cells with isoquinolinesulfonamide derivatives (H7, a protein kinase C inhibitor; HA1004, a control compound), chelytherine (a protein kinase C inhibitor), and phorbol esters (protein kinase C activators). Treatment with H7 significantly attenuated DNA synthesis in proliferating and differentiating trophoblast cells and accelerated the acquisition of progesterone biosynthetic capabilities by trophoblast cells. Treatment with HA1004, the related but functionally distinct isoquinolone, did not significantly affect trophoblast DNA synthesis or proliferation and only weakly increased progesterone accumulation. Chelytherine significantly inhibited trophoblast cell proliferation but failed to influence trophoblast progesterone production significantly. The phorbol ester, 12-O tetradecanoylphorbol acetate, did not significantly influence progesterone accumulation. H7 did not significantly influence the concentration of either P450scc or the mRNA encoding it in Rcho-1 trophoblast cells, or the transcriptional activity of the P450scc gene. The results indicate that signalling pathways sensitive to protein kinase C are involved in the control of trophoblast cell proliferation. Differentiation-dependent production of progesterone is sensitive to H7 but appears to be independent of protein kinase C and occurs at a stage other than P450scc expression. PMID- 9370963 TI - Reproductive efficiency in mink (Mustela vison) treated with the pesticides lindane, carbofuran and pentachlorophenol. AB - Mink are carnivores of agroforestry fringe habitats and are exposed to pesticides that biomagnify within the food chain. Some pesticides are thought to disrupt reproductive and endocrine functions. In Expt 1, four groups of mink (n = 10) were fed either a control diet, or diets treated with lindane (1 mg kg-1 day-1), carbofuran (0.05 mg kg-1 day-1) or pentachlorophenol (1 mg kg-1 day-1) from before breeding until weaning. Mink were mated twice, at 7-8 day intervals. The treatments had no effect on the proportion of mink accepting the first mating; however, lindane and pentachlorophenol caused a decrease in the percentage of females accepting the second mating. Lindane and pentachlorophenol caused a decrease in whelping rate, although litter size was not affected. Carbofuran had no effect on fertility. Mink that mated only once had a lower whelping rate than mink that mated twice; therefore, it could not be determined whether the decreased whelping rates were due to the lack of a second mating or to increased embryo loss. In Expt 2, two groups of mink (n = 15) were fed a control diet or a diet treated with lindane (1 mg kg-1 day-1) from before mating until weaning. Mink were mated twice on two consecutive days. Lindane did not affect mating response at either mating. Whelping rate, but not implantation rate, was decreased by the lindane treatment. The proportion of embryos lost after implantation (implantation scars not represented by kits at whelping) was increased by the lindane treatment. In conclusion, both lindane and pentachlorophenol decreased fertility in mink, and the lindane effect was primarily a result of embryo mortality after implantation. PMID- 9370965 TI - Termination of obligate anoestrus and induction of fertile ovarian cycles in dogs by administration of purified pig LH. AB - The potential role of LH in the initiation of the follicular phase in dogs was investigated by treating anoestrous bitches with highly purified pig LH (n = 16) or saline (n = 8) three times a day for 7 days, beginning in either early anoestrus (days 94-116 of the cycle) or mid-anoestrus (days 124-145). Treatment with LH induced pro-oestrus within 7 days (n = 16), and oestrus (n = 12) and fertile ovulations (n = 7) at 16 + 3 days, while pro-oestrus in bitches treated with saline did not occur until 46-166 days after the start of treatment. Six of the seven ovulating bitches whelped normal litters. The bitches in which pro oestrus but not oestrus occurred were all treated in early anoestrus. During treatment, plasma oestradiol in bitches treated with LH increased from 8 + 2 pg ml-1 to 20 + 5 pg ml-1 within 1 day, and reached higher peak values (45 + 7 pg ml 1) (P < 0.05) than those observed in saline-treated controls (9 + 3 ng ml-1). These results demonstrate that LH treatment alone can terminate anoestrus by inducing a normal follicular phase in dogs. The results also suggest that, in normal cyclic bitches, anoestrus is the result of insufficient LH secretion, and that spontaneous pro-oestrus could be the result of increased LH secretion in the presence of already adequate concentrations of FSH. PMID- 9370964 TI - Electrophysiological basis of human fallopian tubal fluid formation. AB - A preparation for the maintenance of human Fallopian tubal epithelial cells as a polarized layer in primary culture was used to study the electrophysiological basis of tubal fluid formation in terms of the movement of Na+, K+ and Cl- ions. Transepithelial potential difference (PD) and short-circuit current (Iscc) were recorded by mounting the epithelial cells in a modified Ussing chamber. Resistance (R) was calculated from the measurements of PD and Iscc. The epithelia, although confluent, formed a 'leaky' electrical system and resistances greater than 300 omega cm-2 were rarely achieved. The sodium channel blocker, amiloride (100 mumol l-1), produced only small effects on PD and Iscc. The potassium channel blocker, tetraethylammonium chloride (TEA) (25 mmol l-1), also produced small, but significant changes in PD, Iscc and R while the chloride channel blocker, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS) (1 mmol l-1), induced a marked increase in PD and Iscc, and a fall in R, when added to the basal surface of the cells. Bathing the apical surface of the cells with chloride-free medium also produced a marked increase in PD, Iscc and R: bathing the basal surface of the cells with chloride-free medium produced a marked decrease in PD and Iscc. Extracellular ATP (10 mumol l-1), added to either the apical or the basal surface of the cells, induced a transient increase in PD and Iscc and a decrease in R. Amiloride, TEA or furosemide had no effect on the response of the cells to ATP. SITS, applied to the apical surface, significantly reduced the response of the cells to ATP. We conclude that the major driving force for human tubal fluid formation is the transepithelial secretion of chloride ions into the oviduct lumen and that exogenous ATP is a potential modulator of secretion. PMID- 9370966 TI - Effects of treatment with LH releasing hormone before the early increase in LH secretion on endocrine and reproductive development in bull calves. AB - Between 6 and 20 weeks of age an early increase in LH secretion has been reported in Hereford bull calves. Delaying this early increase in LH secretion delays testicular development. This study was designed to determine whether a premature increase in LH secretion during the early postnatal period enhances testicular development. Ten age- and body weight-matched Hereford bull calves were divided into two groups. One group (n = 5) received 200 ng LH releasing hormone (LHRH) i.v. every 2 h for 14 days, between 4 and 6 weeks of age. On the basis of blood samples taken every 15 min for 10 h, mean serum LH and testosterone concentrations and LH pulse frequency were increased by LHRH treatment (P < 0.05). Serum concentrations of FSH were not significantly influenced by treatment (P > 0.05). In treated animals at 24 weeks of age, mean serum testosterone concentrations and LH pulse amplitude were increased (P < 0.05). The concentrations of spermatozoa in electroejeculates collected at 52 weeks of age were greater in LHRH-treated compared with control calves. Testicular growth was enhanced by LHRH treatment and histological evaluation of the testis at 54 weeks of age showed increased spermatogenesis and also larger numbers of Sertoli cells per tubule cross-section as a result of LHRH treatment. We conclude that treatment with LHRH before the early increase in LH secretion altered testicular development and suggest that the early increase in LH secretion in bull calves may be critical for initiating and regulating the progression of reproductive maturation. PMID- 9370967 TI - Effects of administration of testosterone, dihydrotestosterone, oestrogen and fadrozole, an aromatase inhibitor, on sex skin colour in intact male rhesus macaques. AB - For defining the mechanism of control of sex skin colour in male rhesus macaques (Macaca mulatta) by hormones, a spectrocolorimeter was used to monitor skin redness after administration of testosterone, dihydrotestosterone (a non aromatizable androgen), oestradiol or fadrozole (an aromatase inhibitor that blocks the conversion of testosterone to oestrogen). Skin blood flow was measured by laser doppler. Eight 9-14 kg, 5-9 year old intact male rhesus macaques were given hormone, fadrozole or vehicle treatments in a cross-over experimental design. Baseline blood flow and colour measurements were taken in four paired tattoo defined areas on the back and legs of each animal (one pair in non-sex skin, three pairs in sex skin). Colour and blood flow measurements were taken 3-4 days after the first dose and, thereafter, once a week for 3-6 weeks. Measurements taken after treatments were compared with baseline and intra-animal comparisons were made between treatment and vehicle for each animal. In all animals after administration of 4 mg testosterone kg-1 (long-acting), redness in the sex skin areas increased (P = 0.032) by day 3 and returned to baseline values by day 7. Administration of 1 mg oestradiol kg-1 day-1 for 4 days caused increased redness in all animals (P = 0.007) similar in magnitude to that caused by testosterone. Administration of 0.1 mg dihydrotestosterone kg-1 day-1 for 4 days resulted in a nonsignificant decrease in redness (P = 0.09) on days 3-7. Treatment with fadrozole (0.25-0.5 mg kg-1 day-1) for 3 weeks caused sex skin to become significantly less red during treatment (P = 0.014). There was no significant change in redness in non-sex skin areas during any treatment. Sex skin blood flow increased in animals treated with testosterone, correlating with increased redness (R = 0.906), while blood flow in non-sex skin was unchanged. Increased redness after treatment with testosterone and oestrogen, no change in redness with treatment with dihydrotestosterone and a decrease in redness after treatment with fadrozole support the conclusion that oestrogen controls sex skin redness, and testosterone acts indirectly through conversion to oestrogen to cause increased sex skin redness in male rhesus macaques. PMID- 9370968 TI - Effect of oestradiol replacement in ovariectomized chickens on pituitary LH concentrations and concentrations of mRNAs encoding LH beta and alpha subunits. AB - Plasma concentrations of oestradiol and LH and steady-state pituitary concentrations of the mRNAs encoding the LH beta and alpha subunits in the gland were measured at intervals of 1 month for 5 months in female chickens. In addition, feedback regulation by oestradiol of concentrations of mRNAs encoding these LH subunits was studied in ovariectomized young (3-week-old) and adult hens. Concentrations of the mRNAs encoding the LH beta and alpha subunits increased significantly before sexual maturity and the changes were highly correlated with increases in plasma and pituitary concentrations of LH. Ovariectomy significantly reduced circulating plasma concentrations of oestradiol but increased pituitary concentrations of mRNAs encoding LH beta and alpha subunits and pituitary and plasma concentrations of LH in adult laying hens. In addition, in 3-week-old chickens, ovariectomy induced an increase in plasma and pituitary gland concentrations of LH. This ovariectomy-induced mRNA expression and tissue and plasma increases of LH were prevented by oestradiol replacement. These data suggest that a negative feedback mechanism by ovarian oestradiol inhibits LH release from the pituitary and pituitary LH biosynthesis in chickens. PMID- 9370969 TI - Survival and development of bovine blastocysts produced in vitro after assisted hatching, vitrification and in-straw direct rehydration. AB - The purpose of this study was to establish an efficient combination of assisted hatching and cryopreservation procedures for producing bovine embryos in vitro. A total of 1312 day 7 blastocysts were subjected randomly to 14 different combinations of three factors: osmotic stress, assisted hatching and vitrification. Re-expansion, initiation and completion of the hatching process, as well as attachment to the culture dish, were analysed by SAS Genmod procedure. Incubation with sucrose was found to decrease survival rates; among the assisted hatching procedures used, zona fenestration resulted in higher survival rates compared with partial zona dissection and controls; and vitrification decreased survival and further development. The combined effect of sucrose incubation and vitrification decreased further development markedly, as did partial zona dissection followed by vitrification. Partial zona dissection performed in medium containing sucrose severely lowered embryo survival. Zona fenestration without sucrose incubation followed by vitrification did not compromise further embryo development: 86%, 84% and 79% of the blastocysts initiated, completed hatching and attached to the bottom, respectively. These data were not different from the controls (80%, 76% and 63%, respectively; P > 0.05). Cell count analysis revealed a decrease in the total number of cells as a result of the assisted hatching and vitrification compared with controls (135 versus 202, respectively; P < 0.0001). Although embryo transfer results (36% pregnancy rate and 30% calving rate) require further improvement, this combination of methods may prove useful in the commercial production of bovine embryos in vitro. PMID- 9370970 TI - Effect of A23187 or angiotensin II on ovarian metalloproteinase inhibitors and steroidogenesis in rats. AB - The present study examined the effect of the calcium ionophore A23187 or angiotensin II (AII) on the expression of ovarian metalloproteinase inhibitor and activity in rat granulosa cells and intact ovaries. Granulosa cells were collected from rats primed with pregnant mares' serum gonadotrophin (PMSG) and cultured for 24 h with A23187, AII, or the AII receptor antagonist, saralasin, in the presence or absence of LH. Metalloproteinase inhibitor activity and progesterone concentrations were determined in the media. In the A23187 experiment, addition of A23187 to granulosa cells, cultured without LH, decreased inhibitor activity, especially at the concentrations of 10 and 100 mumol l-1 (decrease to 33 +/- 7% and 31 +/- 5% of control culture values, respectively). Addition of LH to the media increased inhibitor activity 3.04 +/- 0.39 times compared with the control; however, A23187 (10 and 100 mumol l-1), in the presence of LH, decreased inhibitor activity by approximately 67%. The ionophore had disparate effects on progesterone production. Without LH, A23187 increased progesterone production by 2.96 +/- 0.47 times at 10 mumol l-1 and by 5.53 +/- 0.65 times at 100 mumol l-1. However, in LH-stimulated cells, progesterone was inhibited by A23187 at 1 and 10 mumol l-1 but was unchanged at 100 mumol l-1. In the angiotensin experiment, addition of AII (0-10,000 nmol l-1) or saralasin (1 mumol l-1) did not affect inhibitor activity or progesterone concentrations compared with control values in the absence or presence of LH. For the angiotensin experiment in vivo, PMSG-primed rats were injected with hCG followed by saralasin (10 mmol l-1) 1 or 3 h later and killed at 4, 8, or 12 h after hCG. Expression of the ovarian tissue inhibitor of metalloproteinase-1 (TIMP-1) increased by 1.7 times at 4 h, 3.3 times at 8 h, and 3.0 times at 12 h after hCG compared with values in ovaries collected at the time of hCG injection. Administration of saralasin at 1 or 3 h after hCG had no effect on expression of TIMP-1 or on serum concentrations of progesterone or oestradiol. In summary, A23187 decreased granulosa cell-derived inhibitor activity, whereas All had no effect. We propose that calcium may play a role in modulating proteolysis associated with ovulation, while AII does not appear to regulate ovarian metalloproteinase inhibitor activity. PMID- 9370971 TI - Transbilayer motion of spin-labelled phospholipids in the plasma membrane of epididymal and ejaculated ram spermatozoa. AB - The transbilayer movement and distribution of spin-labelled phospholipid analogues were studied in the plasma membrane of ram sperm cells isolated from functionally different regions of the epididymis (caput, cauda) and from the ejaculate. As already shown for ejaculated cells, (i) a rapid movement of aminophospholipid analogues phosphatidylserine and phosphatidylethanolamine from the exoplasmic to the cytoplasmic leaflet, and (ii) a slow transbilayer movement of phosphatidylcholine were observed in the plasma membrane of maturating ram sperm cells. This suggests an asymmetric steady state transbilayer distribution of phospholipids, with a preferential enrichment of aminophospholipids on the cytoplasmic leaflet of those cells. The fast inward redistribution of the aminophospholipid analogues is consistent with the presence of an aminophospholipid translocase activity in all three sperm cell preparations. The translocase activity was enhanced slightly during the epididymal transit of spermatozoa. However, compared with epididymal sperm cells, a marked increase in the aminophospholipid translocase activity and a more pronounced phospholipid asymmetry for phosphatidylethanolamine was established for ejaculated spermatozoa. The physiological relevance of the rapid removal of aminophospholipids from the exoplasmic leaflet of the plasma membrane of ram sperm cells is discussed. The quality of sperm cell fractions was characterized by the cell morphology, membrane integrity and the cellular ATP concentration. PMID- 9370972 TI - Ultrasonographic monitoring of antral follicle development in red deer (Cervus elaphus). AB - Ovarian follicular dynamics were monitored in 12 surgically modified red deer hinds (ovaries adhered to vaginal wall) by transvaginal real-time ultrasonography during the luteal cycle, anoestrus and induction of superovulation. All 12 hinds showed evidence of regular luteal (plasma progesterone) cyclicity during the breeding season, although luteal tissue was not observed on the ultrasonograms. During the normal luteal cycle (14-22 days) total numbers of follicles > 3 mm did not vary significantly by day (range of means: 1.8-3.4; P > 0.05). A single large (> or = 6 mm) follicle was usually present on all days except immediately after ovulation (day 0). However, the appearance of new follicles (> or = 3 mm) was not random, and was greatest on day 1 and day 14 (P < 0.05). Tracking of individual follicles revealed irregular waves of emergence and disappearance of the largest follicle, with either one (n = 1), two (n = 3) or three (n = 5) waves observed across nine luteal cycles. New follicles (> or = 3 mm) emerged after regression or ovulation of a large follicle, suggesting a dominance effect. There were no significant differences in the overall mean numbers of follicles during early, mid- and late anoestrus (September, November and April, respectively) but follicle turnover was more rapid during mid-anoestrus as evidenced by a significantly greater number of new small (> 3 mm) follicles (P < 0.001). Administration of superovulatory doses of ovine FSH during the breeding season resulted in a marked increase in the appearance of new follicles within 48 h of initiation of the injection regimen. By termination at 96 h, the time of progesterone withdrawal, the mean number of follicles > 3 mm was significantly higher than for control hinds (9.8 versus 3.0; P < 0.0001). While most follicles ovulated progressively 2-7 days later, about 40% persisted beyond this period. The study demonstrated the presence of discrete patterns of antral follicle growth and regression during the breeding and non-breeding seasons, with the luteal cycle characterized by a variable number (1-3) of dominant follicle waves. Anoestrus represents a period of dynamic changes in follicular turnover. PMID- 9370973 TI - Effects of oocyte maturation media on development of pig embryos produced by in vitro fertilization. AB - Few embryos derived from pig oocytes matured and inseminated in vitro are able to develop to blastocyts in culture. The present study was conducted to examine the effects of oocyte maturation media on the developmental ability of pig oocytes matured and inseminated in vitro. Follicular oocytes collected from ovaries of prepubertal gilts were cultured in NCSU23 medium, tissue culture medium 199 or a modified Whitten's medium. All of the media were supplemented with 0.57 mmol cysteine l-1 and 10% pig follicular fluid. After maturation, some of the oocytes were used for examination of intracellular glutathione content, nuclear maturation and cortical granule distribution. The other oocytes were inseminated in vitro in a modified Tris-buffered medium with cryopreserved, ejaculated spermatozoa for examination of cortical reaction, sperm penetration, male pronuclear formation and blastocyst development. No differences (P > 0.05) were observed in nuclear maturation, cortical granule distribution, sperm penetration, male pronuclear formation, polyspermy and cleavage in oocytes matured in the three media. However, significant (P < 0.05) differences were observed in glutathione content, cortical granule exocytosis, blastocyst development and number of cells in blastocysts. NCSU23 medium gave the best results of the three media, resulting in 5.8 pmol glutathione per oocyte, 97% of cortical granule exocytosis, 30% blastocyst development and 36.8 +/- 17.0 cells per blastocyst. These results clearly indicate that cytoplasmic maturation of pig oocytes was significantly affected by oocyte maturation media even in the presence of cysteine and pig follicular fluid. In addition, it was demonstrated that a large proportion of pig oocytes can develop to blastocysts under in vitro conditions. PMID- 9370974 TI - Cell death during luteal regression in the marmoset monkey (Callithrix jacchus). AB - The mechanism controlling luteal regression in primates is unknown but may involve cell death by apoptosis. Marmoset ovaries containing corpora lutea were studied at different stages of the normal ovarian cycle. Two additional groups of animals underwent induced luteolysis with either the prostaglandin F2 alpha analogue, cloprostenol, or the GnRH antagonist, antarelix, at the mid-luteal phase. Apoptosis in ovarian sections was estimated both by counting the number of cells exhibiting morphological features of apoptosis and by in situ labelling the 3' ends of the DNA fragments with digoxigenin-11-dUTP. Apoptosis was found to be significantly increased in corpora lutea in the early follicular phase (equivalent to the later stage of luteal lifespan) compared with the mid-luteal phase corpora lutea, as judged by either computerized morphometry or 3' end labelling. Apoptosis was also increased by the administration of either cloprostenol or antarelix when using the 3' end labelling end point, but only after cloprostenol when using computerized morphometry. A further form of cell death, characterized by the formation of cytoplasmic vacuoles, was also observed in corpora lutea undergoing both induced and spontaneous regression. These results demonstrate that apoptosis within the primate corpus luteum is increased in both physiological and induced luteal regression. In addition, they show that an alternative form of cell death is involved in both spontaneous and induced luteal regression, although the relative importance of the two mechanisms remains to be determined. PMID- 9370975 TI - Effect of nutrition on testicular growth and plasma concentrations of gonadotrophins, testosterone and insulin-like growth factor I (IGF-I) in pubertal male Soay sheep. AB - Nutritional effects on puberty were studied in Soay rams. Testicular growth is initiated at birth in April and testes reach maximum size in October. Groups of eight lambs were fed for 18 weeks, starting in August, a ration that restricted growth (Group R), the same diet ad libitum (Group F), or a restricted diet for 8 weeks followed by ad libitum feeding (Group R/F). Seasonal increases of plasma FSH, testis size, sexual skin flush and plasma testosterone occurred with similar timing but reduced magnitude in Group R compared with Group F lambs. Testis size and sexual skin flush peaked in all groups at 11 weeks (30 October); the testes of Group F animals were larger before the peak, but similar in size thereafter, compared with testes from Group R/F, and larger throughout the experimental period than testes from Group R. Plasma testosterone was higher in Group F than in Group R lambs from 7 to 17 weeks, but in Group R/F was similar to Group R before 10 weeks (23 October) and similar to Group F thereafter. Testis size, plasma testosterone, plasma insulin-like growth factor I (IGF-I) and liveweight were positively correlated. Ad libitum feeding in August-September (Group F) stimulated increased plasma FSH and LH above values for Group R, but ad libitum feeding initiated in October did not affect gonadotrophin concentrations (Group R/F). Therefore, the effects of improved nutrition on the hypothalamo-pituitary axis, which may have been mediated by circulating IGF-I, were season- or age dependent, and those on the testes included direct stimulation, independent of changes in gonadotrophin concentrations. Nutrition modified the intensity, but not the timing, of peak pubertal reproductive activation. PMID- 9370976 TI - Immunolocalization of 3 beta-hydroxysteroid dehydrogenase, cytochrome P450 17 alpha-hydroxylase/17,20-lyase and cytochrome P450 aromatase in the equine corpus luteum of dioestrus and early pregnancy. AB - The onset of equine chorionic gonadotrophin (eCG) secretion in pregnant mares is associated with an increase in luteal androgen and oestrogen production. The luteal cell type(s) responsible for the increased production of androgens and oestrogens has not been identified in the equine corpus luteum. In this study, we examined the pattern of expression of 3 beta-hydroxysteroid dehydrogenase (3 beta HSD), cytochrome P450 17 alpha-hydroxylase/17,20-lyase (P450(17 alpha)) and cytochrome P450 aromatase (P450arom) by immunohistochemistry in equine luteal tissue collected during dioestrus (days 7-10; n = 4) and early pregnancy, before (days 29-35; n = 4) and after (days 39-45; n = 4) the onset of endogenous eCG secretion. All luteal cells expressed 3 beta-HSD, P450(17 alpha) and P450arom. The distribution of 3 beta-HSD, P450(17 alpha) and P450arom did not differ with stage of the reproductive cycle. The intensity of immunohistochemical staining for 3 beta-HSD did not appear to differ with reproductive stage. In contrast, the intensity of immunostaining for P450(17 alpha) increased after the onset of eCG secretion. The intensity of immunostaining for P450arom increased during pregnancy before the onset of eCG secretion and diminished after the onset of eCG secretion to the intensity seen in dioestrous corpora lutea. This finding suggests that androgen and oestrogen production is not compartmentalized within the equine corpus luteum. Both large and small luteal cells express the steroidogenic enzymes necessary for oestrogen production, and the intensity of immunostaining for P450(17 alpha) and P450arom appears to be stage-specific. PMID- 9370977 TI - Inhibition of bacterial and boar epididymal sperm immunogenicity by boar seminal immunosuppressive component in mice. AB - Intravenous deposition of the immunosuppressive component, isolated from boar seminal vesicle secretion, led to suppression of primary and secondary antibody response to boar epididymal spermatozoa and to bacterial antigens. The most effective suppression of the immune response was achieved in female mice treated with immunosuppressive component 3 days before the immunization with antigen. The treatment with immunosuppressor 3 days after the immunization resulted in less effective immunosuppression. After the primary immunization, male mice displayed low sensitivity to epididymal spermatozoa. The production of IgG and IgM antibodies to spermatozoa was depressed for a relatively long period in female mice treated with immunosuppressor. The immunosuppressive components of the reproductive gland secretions may protect sperm cells from the adverse effect of the immune system cells and enhance the chance of conception. However, seminal immunosuppressive components may play an unfavourable role by producing a predisposition in the reproductive tract to bacterial or viral infections. PMID- 9370978 TI - The distribution and requirements of microtubules and microfilaments during fertilization and parthenogenesis in pig oocytes. AB - Microtubules and microfilaments are major cytoskeletal elements in mammalian ova and are important modulators of many fertilization and post-fertilization events. In this study, the integrated distribution of microtubules and microfilaments in pig oocytes were examined under a laser scanning confocal microscope, and the requirements of their assembly during in vitro fertilization and parthenogenesis in in vitro matured pig oocytes were determined. After sperm penetration, an aster of microtubules was produced in the spermatozoon, and this microtubule aster filled the whole cytoplasm during pronuclear movement. During pronuclear formation after activation by insemination, microfilaments became concentrated at the male and female pronuclei and, after electrical stimulation, at the female pronucleus. At metaphase of cleavage, microtubules were detected in the spindle and microfilaments were found mainly in the cortex. At anaphase, microtubule asters assembled at each spindle pole. During cleavage, large asters filled each daughter blastomere and a microfilament-rich cleavage furrow was observed. Cytochalasin B, a microfilament inhibitor, inhibited microfilament polymerization but affected neither pronuclear formation nor movement. However, syngamy and cell division were inhibited in eggs treated with cytochalasin B. Treatment with nocodazole after sperm penetration inhibited microtubule assembly and prevented migration leading to pronuclear union and cell division. These results indicate that microtubule and microfilament assembly in pig oocytes are integrated during fertilization and are required for the union of sperm and egg nuclei and for subsequent cell division. PMID- 9370979 TI - Establishment of the block against sperm penetration in parthenogenetically activated bovine oocytes matured in vitro. AB - The ability of a single electric pulse to mimic a block against sperm penetration in bovine oocytes matured in vitro was investigated. Confocal laser scanning microscopy detected a global loss of spots, presumed to be cortical granules, stained with Lens culinaris agglutinin, in pulsed oocytes. Transmission electron microscopy revealed that cortical granule exocytosis occurred within 1 min of stimulation and the number of remaining cortical granules was significantly reduced in all pulsed oocytes. The ability of pulsed oocytes to undergo fertilization in vitro was also affected, as only 31% of the pulsed oocytes were penetrated compared with 87% in the control group. Since incidences of penetration in pulsed oocytes (31%), and of polyspermy in control oocytes (18%) did not differ and were highly correlated (P = 0.009) among trials (n = 15), the induced block is considered to be comparable with the natural block triggered by a spermatozoon. The increased resistance of the zona pellucida to pronase E observed in pulsed oocytes suggests that the induced block depends, at least partly, on modifications of zona pellucida glycoproteins. Finally, the majority (66%) of pulsed, penetrated oocytes did not form male pronuclei, probably as a consequence of asynchrony between the formation of female pronucleus and sperm penetration. The reduced ability of the cytoplasm to induce the formation of a male pronucleus was accompanied by a fall in histone H1 kinase activity to basal values by 3 h after stimulation. These results demonstrate that a single electric pulse can induce a block against sperm penetration similar to that of the spermatozoon itself. PMID- 9370980 TI - Health inequality: what the new British government could do. PMID- 9370981 TI - Hostage retrieval. PMID- 9370982 TI - Brief family intervention in adolescents who deliberately self-harm. PMID- 9370983 TI - How to get medical information from the Internet. PMID- 9370984 TI - Illness doesn't belong to us. AB - There has been little research in Britain into the experiences of doctors who are ill. We conducted in-depth interviews with 64 doctors of all grades with a recent illness lasting one month or more. Whether the illness was physical or psychiatric, many expressed the idea that illness is inappropriate for doctors. This idea is a cultural value among doctors which is reinforced by the organization of medical work. It discourages doctors from seeking and obtaining appropriate help when they are ill. PMID- 9370985 TI - Trends in self-poisoning: admissions to a central London hospital, 1991-1994. AB - Self-poisoning is a common reason for admission to hospital; and, although most patients admitted do not have a psychiatric disorder, as a group they are at greatly increased risk of completed suicide. Admissions to a hospital in Central London over a four-year period were examined with special attention to patients admitted more than once. From 1991 to 1994 admissions for self-poisoning rose by 108%, with larger increases in the younger age groups of both sexes. 9% of patients were admitted more than once, the mean interval to repetition being three months. A third of the repeaters were readmitted within one month. The increase in admissions for self-poisoning, which has been noted elsewhere in the UK, is unlikely to be due wholly to changes in clinical practice. In view of the relation between parasuicide and suicide, further research and analysis is urgently needed. PMID- 9370986 TI - A year behind bars: treatment of compound Monteggia fracture by external fixation. PMID- 9370987 TI - Encephalopathy due to hyponatraemia in acute intermittent porphyria. PMID- 9370988 TI - Multiple myeloma with primary amyloidosis. PMID- 9370989 TI - Type II diabetes mellitus presenting as the Charles Bonnet syndrome. PMID- 9370990 TI - An ethical framework for clinical decision-making at the end of life. PMID- 9370991 TI - The Devil's mark and the witch-prickers of Scotland. PMID- 9370992 TI - The influence of Herman Boerhaave. PMID- 9370993 TI - What caused the 1918-30 epidemic of encephalitis lethargica? PMID- 9370994 TI - Evolutionary medicine. PMID- 9370995 TI - Evolutionary medicine. PMID- 9370996 TI - Medical profession and justice. PMID- 9370997 TI - Breast cancer clinic led by a nurse practitioner. PMID- 9370998 TI - Lind's clinical trial and the control of scurvy. PMID- 9370999 TI - Swearing off the oath? PMID- 9371001 TI - Paracetamol hepatotoxicity. PMID- 9371002 TI - Rosacea of the chin. PMID- 9371000 TI - Fever. PMID- 9371003 TI - Monitoring for adverse drug events. PMID- 9371004 TI - Menopause and the risk of thromboembolism. PMID- 9371005 TI - The antibiotics vs. resistant organisms arms race. PMID- 9371006 TI - The antibiotics vs. resistant organisms arms race. PMID- 9371007 TI - Obstructive sleep apnea and secondary hypertension. PMID- 9371008 TI - Pets and Parasites. AB - Which parasites can be transmitted by household cats and dogs? Certainly a variety of potentially dangerous helminths and protozoa can be transmitted to humans from pets but, for the most part, very special conditions must be present before this occurs. Small children, pregnant women and immunocompromised persons are three groups at greater potential risk than the general population. Infants and toddlers may contract visceral or cutaneous larva migrans, tapeworm infections and, rarely, other helminths or protozoa. Pregnant women and their offspring are at special risk for toxoplasmosis. Immunocompromised persons (including those with acquired immunodeficiency syndrome) are susceptible to multiple infections but especially to cryptosporidiosis, an underdiagnosed zoonosis present in contaminated water supplies. Other zoonotic infections (Echinococcosis, Dirofilariasis) rarely appear in the general population but, when they do occur, pose very real diagnostic challenges. The risk of disease transmission from pets can be minimized by taking a few simple precautions such as avoiding fecal-oral contact, not emptying the cat's litterbox if pregnant, washing hands carefully after handling pets, worming pets regularly and supervising toddler-pet interactions. In most cases, the psychologic benefits of pet ownership appear to outweigh the reducible risks of disease transmission. PMID- 9371009 TI - Drug-induced disorders. AB - Recent estimates suggest that each year more than 1 million patients are injured while in the hospital and approximately 180,000 die because of these injuries. Furthermore, drug-related morbidity and mortality are common and are estimated to cost more than $136 billion a year. The most common type of drug-induced disorder is dose-dependent and predictable. Many adverse drug events occur as a result of drug-drug, drug-disease or drug-food interactions and, therefore, are preventable. Clinicians' awareness of the agents that commonly cause drug-induced disorders and recognition of compromised organ function can significantly decrease the likelihood that an adverse event will occur. Patient assessment should include a thorough medication history, including an analysis of all prescribed and over-the-counter medications, vitamins, herbs and "health-food" products to identify drug-induced problems and potentially reversible conditions. An increased awareness among clinicians of drug-induced disorders should maximize their recognition and minimize their incidence. PMID- 9371010 TI - Upper extremity bursitis. AB - Upper extremity bursae are injured through a number of processes, including overuse, hemorrhage, crystal deposition, autoimmune diseases and infection. These injuries may be disabling and can pose significant diagnostic and therapeutic challenges for the clinician. Treatment of the most common forms is directed at pain management and functional rehabilitation through a structured exercise program. Early recognition of infectious bursitis, followed by appropriate surgical and antibiotic treatment, is critical to prevent severe sequelae in these cases. This article reviews the pathophysiology, evaluation and treatment of the three most commonly involved upper extremity bursae: the subacromial, the olecranon and the subscapular bursae. PMID- 9371011 TI - The changing approach to falls in the elderly. AB - The annual incidence of falls is approximately 30 percent in persons over the age of 65 years. The risk of falls is greater in older persons, with the annual incidence increasing to 50 percent in those over age 80. Because of the significant incidence of falls in the elderly, physicians should have an organized approach to fall assessment and prevention. Most falls in the elderly are caused by complex interactions of intrinsic and extrinsic factors. A thorough history is essential to identifying the intrinsic or extrinsic factors involved. Approximately one half of falls in the elderly can be attributed to accidents and extrinsic causes such as slippery floors, and the remainder from intrinsic causes such as lower extremity weakness, gait disorders, effects of medications or acute illness. Extrinsic and intrinsic factors that are identified may be amenable to one of three management approaches: treating acute or reversible deficits, reducing the cumulative burdens of deficits, or using adaptive devices for irreversible deficits. A careful and focused evaluation can identify factors that can be corrected or therapeutic interventions that will lessen the risk of a subsequent fall. PMID- 9371012 TI - Common cardiovascular problems in the young: Part I. Murmurs, chest pain, syncope and irregular rhythms. AB - Cardiovascular signs and symptoms in young people are common and usually represent variants of normal physiology. However, these signs and symptoms can also indicate the presence of important cardiovascular disorders. Innocent heart murmurs can be distinguished from pathologic murmurs by the lack of associated symptoms, as well as their loudness, timing and location. Although most chest pain in this age group is of musculoskeletal or psychogenic origin, cardiac causes can include pericarditis, aortic stenosis and coronary anomalies. Syncope is usually vasovagal in origin and has a benign prognosis. Sinus arrhythmia and isolated extrasystoles are the most common causes of irregular cardiac rhythms in the young. Multiform premature ventricular contractions, couplets and ventricular tachycardia may indicate underlying cardiac disease. PMID- 9371014 TI - Minocycline-induced hyperpigmentation. Treatment with the neodymium:YAG laser. PMID- 9371013 TI - New oral therapies for type 2 diabetes. AB - Over the past few years, several oral agents for the treatment of type 2 diabetes have become available in the United States. Metformin, a biguanide that has been used for decades in other countries throughout the world, improves glycemic control without exacerbating hyperinsulinemia or promoting weight gain. This agent has recently been reintroduced in the United States. Acarbose is an alpha glucosidase inhibitor that improves glycemic control by decreasing the intestinal absorption of glucose, thereby decreasing postprandial glucose elevations. The use of metformin and acarbose may be limited by their side effects and potential risks, especially the risk of lactic acidosis with metformin. The third newly available agent, troglitazone, has been shown to improve insulin sensitivity. Combinations of metformin, acarbose and troglitazone may facilitate improved glycemic control without the use of insulin, or they may allow sulfonylurea or insulin dosages to be reduced, in this way minimizing the adverse effects of hyperinsulinemia. Unfortunately, current oral therapies do not prevent the inevitable decline in glycemic control that occurs during the natural history of type 2 diabetes. PMID- 9371015 TI - Quality of care in dermatology. The state of (measuring) the art. PMID- 9371016 TI - Ensuring quality of dermatologic care in the US health care system. PMID- 9371017 TI - Ethics in the medical profession. PMID- 9371018 TI - American Academy of Dermatology guidelines of care. Development and process. AB - Medical practice guidelines are being developed at an accelerating pace, in all areas of medicine, for a wide range of uses. The field of practice guideline development is not new, but a number of important economic and health care issues have renewed interest in their creation. In 1987, in response to many of these issues, the American Academy of Dermatology took a leadership role and began a process designed to develop guidelines for disease entities treated by dermatologists. The result was a set of clinical practice guidelines and the most comprehensive dermatology guideline development processes to date. Herein we describe the guideline development process in its current, refined form and discuss some of its unique and important characteristics. New applications of guidelines, outside of clinical practice improvement, have made their development controversial. Nevertheless, it is important for the medical profession to lead in this effort, and the American Academy of Dermatology continues to explore ways to refine and update its guidelines to reflect the latest medical science and technology. PMID- 9371020 TI - Quality improvement and management in a dermatology office. PMID- 9371019 TI - Quality of care and the quality assurance manual of the American Academy of Dermatology. PMID- 9371021 TI - The marriage of guidelines of care and outcomes. PMID- 9371022 TI - Quality of care in the diagnosis of melanoma and related melanocytic lesions. PMID- 9371023 TI - Quality safeguards for managed care. PMID- 9371024 TI - Profitability of a university-based clinic using benchmark time lengths for clinical encounters. AB - Reductions in reimbursement are applied to all physicians in a region equally. However, physicians do not practice in equivalent situations. For example, there are few fiscal allowances for academic functions associated with teaching and administration. Furthermore, university-based physicians may practice in clinical venues that cannot be as efficient as nonuniversity sites. Unavoidable inefficiencies may include (1) the costs of maintaining one historical record for a large noncontiguous practice; (2) university-required holiday schedules and sick leave, making university personnel less productive; (3) noncompetitive overhead rates assigned to clinic components by university financial offices; (4) university-based accounting systems that are not designed for effective cost control and the timely generation of useful management information; and (5) poorly managed billing services. Until now, declining reimbursements have generally led to sufficient efficiencies in delivery so that revenues and expenses can be in equilibrium. PMID- 9371025 TI - Diagnostic accuracy and precision in assessing dermatologic disease. Problem or promise? PMID- 9371027 TI - Screening for skin cancer in primary care settings. AB - OBJECTIVE: To estimate the frequency of recorded screening for skin cancer in primary care settings. DESIGN: Retrospective observational cohort study. SETTING: Two academically affiliated Department of Veterans Affairs Medical Centers. SUBJECTS: Two hundred randomly selected patients at least 50 years old and receiving care at outpatient medical clinics. MAIN OUTCOME MEASURE: Frequency of documented skin examinations, in comparison with other tests routinely done as screening, during a 2-year period. METHODS: Medical record review to identify how often selected components of the physical examination and specific procedures were documented during ambulatory visits. RESULTS: Among the 200 subjects, the frequency of documented examinations and procedures included fecal occult blood testing in 120 (60%), rectal examination in 128 (64%), and sigmoidoscopy in 93 (47%), prostate examination was performed in 114 (59%) of 193 men. In contrast, skin examination was documented in only 56 (28%) of 200 subjects (P < .001 for each comparison with other tests). As an estimate of the "true" frequency of screening for skin cancer, 35 (18%) of 165 patients without skin-related complaints had a documented skin examination. CONCLUSION: Skin cancer screening is infrequently documented and therefore possibly omitted in the context of primary care visits. PMID- 9371026 TI - The diagnostic yield of histologic examination of seborrheic keratoses. AB - OBJECTIVE: To examine the diagnostic yield in submitting clinically diagnosed seborrheic keratoses for routine microscopic examination. DESIGN: Retrospective examination of preoperative and postoperative diagnoses based on information provided by the clinician on the laboratory worksheet and the subsequent histopathologic diagnosis. SETTING: A regional nonhospital-based dermatopathology laboratory with specimens submitted by physicians (dermatologists and nondermatologists) practicing in a 4-state midwestern region of the United States. PATIENT MATERIAL: A total of 5592 cutaneous pathology reports were reviewed. Specimens submitted with a preoperative clinical diagnosis of seborrheic keratosis, with or without a modifier, were examined. A comparison group with the clinical diagnosis of melanocytic nevus was reviewed. MAIN OUTCOME MEASUREMENT: Preoperative clinical diagnoses were compared with the microscopic diagnoses. RESULTS: Of 577 specimens clinically diagnosed and submitted as seborrheic keratoses, 37 (6.4%) were histologically diagnosed as malignant tumors. The rate of malignant tumors increased when clinical information suggested findings beyond the classic clinical presentation, such as irritation, or when a malignant tumor was considered in the differential diagnosis. Two lesions that histologically proved to be melanomas were in this group. Comparison of the seborrheic keratosis group with the nevus group showed that seborrheic keratoses were more likely to be malignant tumors than were melanocytic nevi. Clinically diagnosed seborrheic keratoses submitted by dermatologists were more likely than clinically diagnosed melanocytic nevi to be melanomas. CONCLUSIONS: Our data suggest that there were differences in the rate of malignant tumors between dermatologists and nondermatologists and that clinically diagnosed, surgically removed seborrheic keratoses are more likely than clinically diagnosed, surgically removed melanocytic nevi to be malignant tumors. PMID- 9371028 TI - Patient satisfaction. Quality of care from the patients' perspective. PMID- 9371029 TI - Improved discriminative and evaluative capability of a refined version of Skindex, a quality-of-life instrument for patients with skin diseases. AB - OBJECTIVE: To improve Skindex, a dermatologic quality-of-life instrument. DESIGN: Cross-sectional and longitudinal questionnaire study. SETTING: Dermatology clinic of a Veterans Affairs hospital and private dermatology practices. PATIENTS: Patients waiting for dermatology appointments; 201 patients responded to the original version of Skindex and 692 additional patients to the revised version. MAIN OUTCOME MEASURES: Reproducibility, internal consistency reliability, and validity of the revised version of Skindex. The revised version was compared with the original in 3 ways: the amount of time patients need to complete it; discriminative capability, determined as the number of items to which patients chose the same response; and evaluative capability, determined as the number of scales that were responsive to patients' reports of clinical change. RESULTS: With the revised 29-item version of Skindex, scale scores were reproducible after 72 hours (r = 0.88-0.92) and were internally reliable (Cronbach alpha = 0.87 0.96). The instrument demonstrated both construct and content validity; patients with psoriasis and eczema responded with higher scores than those with isolated lesions; in an exploratory principal axes factor analysis with an oblique rotation, 97% of the common variance was explained by 3 factors that correlated with the a priori scales; and most patients' responses to an open-ended question about their skin disease were addressed by items in the instrument. The average time to complete the revised instrument was 5 minutes (compared with 15 minutes for the original version). For only 3 items (10%) did 70% or more of patients choose the same response (vs 17 [28%] of items in the original version). All scales changed significantly in the expected direction in patients who reported that their skin had changed after 3 months (vs only 3 of 8 scales originally). CONCLUSION: The 29-item version of Skindex remains reliable and valid, but has decreased respondent burden and improved discriminative and evaluative capability. PMID- 9371030 TI - Reliability testing of the dermatology index of disease severity (DIDS). An index for staging the severity of cutaneous inflammatory disease. AB - OBJECTIVES: To describe a new severity of illness index for inflammatory skin disease called the Dermatology Index of Disease Severity (DIDS), and to show its preliminary use and reliability in staging disease in patients with psoriasis and dermatitis. DESIGN: Interobserver rating study using the DIDS with as many as 10 observers independently rating the same patient at a single point in time. SETTING: Ambulatory care clinics at an academic medical center with patients from various socioeconomic backgrounds. PATIENTS: Thirty-four patients with psoriasis and 15 patients with dermatitis were included in the study. MAIN OUTCOME MEASURES: The severity of illness for each patient was rated as 1 of 5 stages: 0, no evidence of clinical disease; I, limited disease; II, mild disease; III, moderate disease; and IV, severe disease. The degree of interobserver concordance was measured by the Cohen kappa statistic. RESULTS: All 5 stages were represented in the study of patients with psoriasis. The overall kappa statistic was 0.76, which is defined as substantial interobserver concordance. The use of the instrument in dermatitis showed good consensus in staging, where the kappa statistic was 0.41. CONCLUSION: We introduce an easy and efficient instrument for staging the severity of illness in inflammatory cutaneous diseases. The reliability of the DIDS is demonstrated in patients with psoriasis and in patients with dermatitis. PMID- 9371031 TI - Is a simple generic index of dermatologic disease severity an attainable goal? PMID- 9371032 TI - A papulonecrotic eruption in a young man. Lymphomatoid papulosis. PMID- 9371033 TI - A self-healing tumor on the upper lip. Primary cutaneous CD30+ large cell anaplastic T-cell lymphoma (LCAL). PMID- 9371034 TI - Ulcerated nodules and papules on the neck and chest. Cutaneous Hodgkin disease (HD). PMID- 9371035 TI - An erythematous plaque above the ear. Skin involvement by a B-cell follicular centrocytic/centroblastic lymphoma. PMID- 9371036 TI - Pigmentary demarcation lines as markers of neural development. PMID- 9371037 TI - Malignant melanoma vs benign tumors in the young. PMID- 9371038 TI - Estrogen, skin aging, and study design. PMID- 9371039 TI - Usefulness of paraclinical follow-up in stage I melanoma. PMID- 9371040 TI - Prevalence of methicillin-resistant Staphylococcus aureus in outpatients with psoriasis, atopic dermatitis, or HIV infection. PMID- 9371041 TI - Plantar epidermal cysts in children. PMID- 9371042 TI - Therapy with oral psoralen plus UV-A for erythema multiforme. PMID- 9371043 TI - Docetaxel chemotherapy induces transverse superficial loss of the nail plate. PMID- 9371044 TI - What is a cost-effectiveness analysis? PMID- 9371045 TI - The impact of Title VII departmental and predoctoral support on the production of generalist physicians in private medical schools. AB - Although federal support for medical education comes from several sources, only 1 targets generalist education--Title VII of the Public Health Service Act. With governmental streamlining and downsizing, the federal investment in medical education should be evaluated. We tested the relationship between 2 Title VII authorities and presence of a medical school generalist training infrastructure, and the relationship between this infrastructure and generalist production. Based on our definitions for receipt of Title VII support, generalist infrastructure, and generalist production, we found that, for private schools, sustained receipt of Title VII funds directed for undergraduate medical education is positively associated with presence of family medicine departments, which is positively associated with higher rates of generalist production. Establishment and maintenance of family medicine departments in private schools and their generalist production are positively associated with Title VII support. Title VII support in public schools, the major generalist producers, has less of a unique measurable impact on generalist production. PMID- 9371046 TI - Concerns regarding universal varicella immunization. Time will tell. AB - The American Academy of Pediatrics, the Advisory Committee on Immunization Practices, and the American Academy of Family Physicians now recommend universal immunization for varicella for all susceptible children and adolescents. Although the varicella vaccine appears safe and efficacious, it is unknown how universal immunization will influence the epidemiology of varicella infections. The duration of immunity, both conferred and passive reinoculation, remains a concern and must continue to be evaluated in the population of vaccinees. As universal immunization is implemented, the cost-effectiveness of such a program will need to be evaluated. Physicians and parents must be educated about the risks and benefits of vaccination vs natural infection. PMID- 9371048 TI - Do as I do, not as I say. PMID- 9371047 TI - Do physicians do as they say? The case of mammography. AB - OBJECTIVE: To assess the utility of survey-based physician policy in predicting actual mammography ordering behavior, as measured by medical record abstraction. DESIGN: Cross-sectional survey of practicing community physicians. Responses were correlated with data abstracted from the medical records of patients in the practices of the participating physicians. PARTICIPANTS: Family and general practitioners in Washington State. Medical records of female patients aged 40 to 80 years provided data on actual mammography performance. MAIN OUTCOME MEASURES: The proportions of female patients aged 40 to 49 and 50 to 80 years who had received a screening mammogram within the previous 2 years. RESULTS: Of the more than 100 potential predictors available, only 4 were significantly associated with screening rates for women younger than 50 years and only 3 were associated with screening rates for older women. Regression models explained only 21% to 25% of the variance in screening rates. Physician estimates of screening rates were poorly correlated with actual screening rates. CONCLUSIONS: Practicing physicians do not know how well they screen their patients using mammography. Extensive survey data, including direct estimates of behavior, demographics, policy measures, and case scenario responses, were of limited use in predicting actual screening rates. Our results underscore the importance of using data rather than proxy measures to study physician performance. PMID- 9371049 TI - A decision analysis to guide antibiotic selection for Chlamydia infection during pregnancy. AB - OBJECTIVE: To analyze the cost and effectiveness of different antibiotic combinations for the treatment of infection with Chlamydia trachomatis in pregnant women. METHODS: Using availability treatment effectiveness rates from the literature, a decision analysis model was constructed to determine the effectiveness and cost of therapy with 4 antibiotics shown to be useful for Chlamydia infection during pregnancy. Women who were still infected after initial therapy were then treated with a second antibiotic. Outcomes included the total cost of the treatment (including pretreatment and posttreatment cultures and antibiotic cost) and treatment failure rates. RESULTS: The lowest failure rates could be achieved with the use of amoxicillin followed by azithromycin for treatment failures or azithromycin followed by clindamycin hydrochloride. When costs were compared, a strategy starting with amoxicillin followed by azithromycin for nonresponders was favored, with costs approximately 15% lower than starting with azithromycin followed by amoxicillin. Strategies using clindamycin were significantly more expensive. The drug combination recommended by the Centers for Disease Control and Prevention (erythromycin followed by amoxicillin in nonresponders) was more expensive than amoxicillin-azithromycin and had one of the highest failure rates. Variation in the cost of the medications and in the effectiveness of the antibiotics under consideration did not significantly alter the findings. CONCLUSIONS: For pregnant women infected with Chlamydia, initiating treatment with amoxicillin, 500 mg 3 times a day for 7 days, followed by a single 1-g dose of azithromycin for nonresponders is the most cost-effective strategy for treatment. PMID- 9371050 TI - The effects of insurance coverage on the quality of prenatal care. AB - OBJECTIVE: To compare the quality of prenatal care provided to patients with traditional fee-for-service, health maintenance organization, and Medicaid insurance using an evidence-based, community-derived prenatal care guideline. DESIGN: Retrospective cohort study. SETTING: Seven private and hospital-based prenatal care sites in a suburban county in southeast Michigan. PATIENTS: A stratified random sample of 267 patients (93 with Medicaid, 92 with health maintenance organization, and 82 with fee-for-service insurance) receiving prenatal care from community physicians (obstetricians-gynecologists and family practitioners) between January 1, 1991, and December 31, 1992. MAIN OUTCOME MEASURE: Adherence to explicit prenatal care criteria as measured by an evidence based prenatal care guideline developed by a community panel. "Quality scores" were compared across groups in 4 areas: performance of prenatal screening procedures or tests, visit-based screening, substance use screening, and clinician management of abnormal clinical findings. RESULTS: Patients with Medicaid insurance presented for prenatal care significantly later in pregnancy (14.5 vs 10.5 weeks, P < .01). No significant differences were seen between groups in quality scores for screening tests, clinician management of abnormal clinical findings, visit-based screening, or substance use screening. The overall similarity in quality scores did obscure some significant differences in adherence to individual criteria, particularly in the area of screening tests. Significantly more patients with Medicaid were screened for genital infection (P < .001) and fewer for gestational diabetes (P < .001) or anemia (P < .001) than patients in the other 2 groups. CONCLUSIONS: Although patients with Medicaid presented for prenatal care later in pregnancy and received a different "package" of screening tests than the other 2 groups, there was no overall measurable difference in the quality of prenatal care provided to patients with Medicaid, health maintenance organization, and fee-for-service insurance. Clinicians may have altered screening protocols based on preexisting perceptions of patient risk. Although summary quality measures are a promising tool for comparative research, they provide an incomplete picture of the quality of the prenatal care process and must be interpreted with caution. PMID- 9371051 TI - Can case-finding instruments be used to improve physician detection of depression in primary care? AB - OBJECTIVE: To explore the issue of diagnostic specificity for major depression in the primary care setting by examining the relative accuracy of 3 methods to detect major depression in primary care. DESIGN: Comparison of performance characteristics of 3 case-finding methods for depression (ie, the Center for Epidemiologic Studies-Depression scale [CES-D], unaided physician detection, and "augmented" physician detection by use of a case-finding instrument), with the standard criterion being the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised (DSM-III-R). SETTING: The offices of 50 family physicians from private and academic practice in southeastern Michigan. PATIENTS: Adult patients (N = 1580) who presented for routine care, from which a weighted random sample of 425 patients completed the Structured Clinical Interview for DSM-III-R. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive predictive value, and positive likelihood ratio for each case-finding method. RESULTS: Major depression was present in 13.4% of the sample. Both the CES-D and unaided physician detection methods performed poorly in identifying patients who met DSM-III-R criteria for major depressive disorder. The CES-D had high sensitivity but low specificity at standard and high cut points, resulting, respectively, in low positive predictive values (0.307 and 0.385) and low positive likelihood ratios (2.9 and 4.0). Unaided physician detection showed lower sensitivity, higher specificity, and a slightly higher positive predictive value (0.45) and positive likelihood ratio (4.9). Raising of the CES-D threshold for a positive test did not enhance the detection of depression. Augmented physician detection with CES-D scores resulted in minimal improvement. Although the positive predictive value and positive likelihood ratio increased to 0.50 and 6.1, respectively, using the most stringent case-finding definition (ie, physician identification plus the CES-D score [score > or = 22]), the proportion of depressed patients who were correctly identified decreased to 26.9%. CONCLUSIONS: Neither high scores on the CES-D nor unaided physician detection accurately identified patients with major depression who were seen in primary care settings, while the supplementation of physician detection with CES D scores had a minimal net effect on the accuracy of detection. The data do not support the routine use of the CES-D as a primary care screening instrument for depression, either as a stand-alone measure or as a supplement to physician detection. PMID- 9371052 TI - Improving the follow-up of patients with abnormal Papanicolaou smear results. AB - A review of the literature on adherence with recommended follow-up after an abnormal screening Papanicolaou smear result reveals that many women do not receive adequate follow-up. Primary care providers can influence the number of women who undergo timely colposcopy or a subsequent Papanicolaou smear by addressing common barriers to follow-up. Physicians should anticipate fears commonly experienced by women when they learn of abnormal Papanicolaou smear results, including fear of cancer, fear of pain during colposcopy, and fear of loss of sexual or reproductive function. An awareness that certain populations are at especially high risk of inadequate follow-up, including black and Hispanic women, women with less than a high school education, and women of low socioeconomic status, can help physicians target their efforts. Practical strategies for improving follow-up include speaking directly with the patient about results, emphasizing the precancerous nature of most lesions, actively preparing the patient for colposcopy by describing the procedure and its complications, and addressing fears about the common treatment options for cervical intraepithelial neoplasia. Office-based reminder systems and educational materials may also be used as adjuncts to personal contact. PMID- 9371053 TI - Correction of deficiencies in flexible fiberoptic sigmoidoscope cleaning and disinfection technique in family practice and internal medicine offices. AB - To assess whether deficiencies exist in the processing of contaminated flexible fiberoptic sigmoidoscopes in family practice and internal medicine offices and whether training of office personnel results in a correction of identified deficiencies, we conducted a prospective review of sigmoidoscope processing in family practice and internal medicine offices before and after a training course. Participants were questioned on their current endoscope processing for 17 standards before and 2 months after receiving training. The 19 offices had between 4 and 11 deficiencies per office before training, with an average of 6.8 deficiencies per office. After training, deficiencies ranged from 0 to 8, with an average of 0.9 deficiencies per office (P < or = .001; Student t test). Personnel responsible for processing flexible sigmoidoscopes in family practice and internal medicine offices are insufficiently trained for this function. Endoscopes are not being processed according to current standards. After a 2-hour training period, these persons maintain their equipment close to or according to standards. PMID- 9371054 TI - Sabotaging one's own medical care. Prevalence in a primary care setting. AB - This study determines the prevalence of medically self-sabotaging behaviors reported by patients in a primary care setting. A 19-item self-report survey was completed by patients on-site at the Family Medicine Clinic, University of Oklahoma College of Medicine-Tulsa. Four hundred eleven consecutive male and female patients were seen for nonemergent care. Each of the 19 items was endorsed by at least 1 respondent. The most commonly endorsed self-sabotaging behaviors were not seeking medical care when needed (37.2%) and not taking a prescribed medication (25.1%). Significantly more women (26.4%) than men (17.5%) reported not taking a prescribed medication (P < .05). After excluding these 2 commonly endorsed items, 27 (6.6%) of the respondents reported at least 1 other self sabotaging behavior, with most indicating 1 (63.0%) or 2 (22.2%); the remaining 4 individuals reported 4 to 12 behaviors. Significantly more men (4.8%) than women (0.6%) reported not following instructions from a physician or nurse to prolong illness (P < .05). A few patients (6.6%) seen in a primary care university outpatient clinic acknowledged the active and intentional sabotage of their medical care, beyond not taking a prescribed medication or seeking medical care when needed. This is probably a conservative estimate and indicates that medical care is actively compromised by a few patients. PMID- 9371055 TI - The changing classification of non-Hodgkin's lymphomas. AB - Treatments for non-Hodgkin's lymphomas vary widely. Because all treatments are not useful to all patients, the non-Hodgkin's lymphomas must be divided into clinically relevant subgroups. Previous systems used to subdivide the non Hodgkin's lymphomas were based on morphology. Later systems added immunologic subgrouping. The International Lymphoma Study Group recently has proposed that lymphomas be grouped as clinical-pathologic entities. Diagnoses based on this system were much more accurate than those using previous systems, but much work remains to be done in the classification of these cancers. PMID- 9371056 TI - Laparoscopic surgery for cancer patients. AB - Laparoscopy is an effective tool for diagnosis and staging of malignancies. Laparoscopic resection of abdominal tumors has been performed rarely, with two exceptions: laparoscopic adrenalectomy and laparoscopic resection of colorectal cancer. One of the best applications of minimally invasive surgery is the use of laparoscopic techniques for palliation of abdominal cancer. Requiring thorough training and preparation of surgeons and mandating their strict credentialing will reduce the risk of complications from laparoscopic surgery. PMID- 9371057 TI - Non-Hodgkin's lymphomas: current classification and management. AB - Considerable progress has been made in the classification of non-Hodgkin's lymphomas during the past 15 years, and the use of specific monoclonal antibodies directed against cell surface antigens has contributed to the understanding of the immunology of the disease. Early-stage indolent lymphoma is treated with radiotherapy; treatment of advanced-stage indolent lymphoma varies. Aggressive lymphomas are treated with combination chemotherapy with or without regional radiotherapy, and highly aggressive lymphomas are treated with regimens similar to those for children with leukemia. PMID- 9371058 TI - Time for legalized distribution of illegal drugs? PMID- 9371059 TI - The changing role of the pathologist. PMID- 9371060 TI - Practice patterns in hypertension. PMID- 9371061 TI - A role for the sick role. PMID- 9371062 TI - Clinical opinions on transfusion triggers. PMID- 9371063 TI - Ordering radiographs with the law in mind. PMID- 9371064 TI - Virtual reality in medical training. PMID- 9371065 TI - Current and projected rates of hip fracture in Canada. AB - OBJECTIVE: To determine the current values and estimate the projected values (to the year 2041) for annual number of proximal femoral fractures (PFFs), age adjusted rates of fracture, rates of death in the acute care setting, associated length of stay (LOS) in hospital, and seasonal variation by sex and age in elderly Canadians. DESIGN: Hospital discharge data for fiscal year 1993-94 from the Canadian Institute for Health Information were used to determine PFF incidence, and Statistics Canada population projections were used to estimate the rate and number of PFFs to 2041. SETTING: Canada. PARTICIPANTS: Canadian patients 65 years of age or older who underwent hip arthroplasty. OUTCOME MEASURES: PFF rates, death rates and LOS by age, sex and province. RESULTS: In 1993-94 the incidence of PFF increased exponentially with increasing age. The age-adjusted rates were 479 per 100,000 for women and 187 per 100,000 for men. The number of PFFs was estimated at 23,375 (17,823 in women and 5552 in men), with a projected increase to 88,124 in 2041. The rate of death during the acute care stay increased exponentially with increasing age. The death rates for men were twice those for women. In 1993-94 an estimated 1570 deaths occurred in the acute care setting, and 7000 deaths were projected for 2041. LOS in the acute care setting increased with advancing age, as did variability in LOS, which suggests a more heterogeneous case mix with advancing age. The LOS for 1993-94 and 2041 was estimated at 465,000 and 1.8 million patient-days respectively. Seasonal variability in the incidence of PFFs by sex was not significant. Significant season-province interactions were seen (p < 0.05); however, the differences in incidence were small (on the order of 2% to 3%) and were not considered to have a large effect on resource use in the acute care setting. CONCLUSIONS: On the assumption that current conditions contributing to hip fractures will remain constant, the number of PFFs will rise exponentially over the next 40 years. The results of this study highlight the serious implications for Canadians if incidence rates are not reduced by some form of intervention. PMID- 9371066 TI - Is Creutzfeldt-Jakob disease transmitted in blood? Is the absence of evidence of risk evidence of the absence of risk? PMID- 9371067 TI - Physicians, finder's fees and free, informed consent. PMID- 9371068 TI - "Say, are you psychiatrists still using ECT?". PMID- 9371069 TI - A prion primer. AB - By biological and medical criteria, prions are infectious agents; however, many of their properties differ profoundly from those of conventional microbes. Prions are "encoded" by alterations in protein conformation rather than in nucleic acid or amino acid sequence. New epidemic prion diseases (bovine spongiform encephalopathy and new variant Creutzfeldt-Jakob disease) have recently emerged under the active surveillance of the modern world. The risk of contracting prion disease from blood products or other biologicals is now a focus of worldwide concern. Much has been discovered about prions and prion diseases, but much remains to be done. PMID- 9371070 TI - Notifying patients exposed to blood products associated with Creutzfeldt-Jakob disease: integrating science, legal duties and ethical mandates. AB - The issue of notifying people who have been exposed to blood products that have been associated with Creutzfeldt-Jakob disease (CJD) has arisen at a time when the Canadian blood system is under intense scrutiny. As a result, the Canadian Red Cross Society issued a recommendation to health care institutions that recipients of CJD-associated blood products be identified, notified and counselled. Although Canadian jurisprudence in the realm of informed consent may support a policy of individual notification, a review of the scientific evidence and the applicable ethical principles arguably favours a policy of a more general public notification. Indeed, situations such as this require a unique approach to the formation of legal and ethical duties, one that effectively integrates all relevant factors. As such, the authors argue that individual notification is currently not justified. Nevertheless, if a system of general notification is implemented (e.g., through a series of public health announcements), it should provide, for people who wish to know, the opportunity to find out whether they were given CJD-associated products. PMID- 9371071 TI - The need for specialized training programs in palliative medicine. AB - Canada faces a significant and growing burden of terminal illness. There are major unresolved economic, ethical and social issues related to care at the end of life. Despite the international reputation for Canadian efforts in palliative care, the medical profession in Canada has largely failed to recognize the importance of the field, as evidenced by the lack of commitment on the part of most medical faculties at Canadian universities to developing academic strength in palliative medicine, the lack of content in the undergraduate curriculum and of postgraduate programs in palliative medicine, and the lack of support for research into end-of-life care. The authors propose a conjoint initiative by the Royal College of Physicians and Surgeons of Canada and the College of Family Physicians of Canada to develop specialized training programs in palliative medicine as a critical step in addressing this crisis. PMID- 9371072 TI - Creutzfeldt-Jakob disease: the Canadian situation. PMID- 9371073 TI - Harmonized sales tax a taxing issue for MDs in Atlantic Canada. AB - Physicians in 3 atlantic provinces say the linking of provincial sales taxes with the GST exacerbates the inequity physicians face because it yet again adds to their overhead costs. Physicians in Nova Scotia have already won an annual rebate to compensate them for the heavier tax burden. Doctors in the Maritimes warn that heavier taxes make recruiting there even more difficult. PMID- 9371074 TI - Jewish and secular medical ethics share themes but diverge on issues such as heroic measures. AB - An american expert on Jewish medical ethics explained the nuances of these rules during a recent address in Ottawa. Although Jewish and secular rules concerning medical ethics often coincide, they diverge in several important areas, including the subject of patient autonomy. PMID- 9371075 TI - One-stop care at breast centre another sign of patients' increasing influence. AB - The Ottawa Regional Women's Breast Health Centre is an example of a new wave of Canadian clinics that are trying to offer improved quality of care for women with breast abnormalities. The new centres are a response to patients' request for changes in the way care is provided. PMID- 9371076 TI - Taking health care to factory floor proves smart move for growing Ontario company. AB - A fully equipped, state-of-the-art wellness centre that employs physicians and other health care providers to meet the health needs of more than 1200 employees is being credited with giving a Canadian company a leg up on the competition. PMID- 9371077 TI - Ignore growing patient interest in alternative medicine at your peril, MDs warned. AB - Canada now has an institute to study alternative medicine and seek evidence concerning it. The founder, endocrinologist Wah Jun Tze, says most physicians appreciate that the institute will seek to find evidence for unproven therapies. It recently named a research director, and expects to have protocols for randomized, controlled studies in place by the new year. Herbal remedies are one likely candidate for study. PMID- 9371078 TI - Labrador program prepares MDs for northern, remote practice. AB - Across Canada, residency programs are attempting to train more physicians to practise in rural and remote areas. The Northern Family Education Program developed in Newfoundland and Labrador is proving that physicians can learn to like life in remote areas. PMID- 9371079 TI - When medicine moves to the Internet, its legal issues tag along. AB - The Internet is opening up possibilities for physicians to provide many health care services without actually meeting patients face to face. What is not clear is who will regulate the quality of these services and who is responsible when something goes wrong. PMID- 9371080 TI - Qualitative research articles: information for authors and peer reviewers. PMID- 9371081 TI - Biochemical and genetic tests for inhibitors of Leishmania pteridine pathways. AB - The study of antifolate-resistant mutants of the protozoan parasite Leishmania has provided useful information about genetic processes such as gene amplification and mutation and knowledge of the unique features of the pteridine metabolic pathway in this primitive eukaryote. The novel bifunctional dihydrofolate reductase-thymidylate synthase (DHFR-TS) is an essential enzyme, yet most DHFR-TS inhibitors show little promise as potential drugs. Leishmania possess a novel alternative pteridine reductase (PTR1) which is relatively insensitive to methotrexate. We have proposed that the ability of PTR1 to serve as a metabolic bypass and thus modulate drug inhibition of DHFR-TS activity may be responsible for the poor efficacy of many antifolates. In this work, we have sought inhibitors of L. major PTR1 from a collection of 74 compounds. The most potent inhibitors were also tested against L. major DHFR-TS and human DHFR and several compounds showing good activity for PTR1 alone, or for all three reductases, were identified. The activity of these compounds was tested against wild-type promastigotes, and those which were potent inhibitors of both PTR1 and DHFR-TS (but not those active against only PTR1) showed good potencies. Growth inhibition tests of L. major mutants, lacking PTR1 or DHFR-TS (ptr1- and dhfr-ts- knockouts) or overexpressing PTR1, were used as a "genetic screen" to assess whether these two pteridine reductases were targets in vivo. Remarkably, only one compound showed a methotrexate-like pattern of inhibition. Six compounds showed good inhibition of Leishmania growth regardless of PTR1 or DHFR-TS levels. These findings suggest that Leishmania cells contain multiple targets for a diverse set of antifolates, with one or more significant targets in addition to DHFR-TS and PTR1. This emphasizes the necessity of combined biochemical and genetic screens in efforts to rationally design chemotherapeutic strategies in Leishmania. PMID- 9371082 TI - Haemonchus contortus: cloning and functional expression of a cDNA encoding ornithine decarboxylase and development of a screen for inhibitors. AB - Polyamines (PA) are essential for viability and replication of all cells; organisms either synthesize PA or acquire them from the environment. How nematodes that parasitize the gut satisfy their PA requirement has not been resolved. The primary regulatory enzyme in PA biosynthesis in most animals is ornithine decarboxylase (ODC). This enzyme has recently been characterized in free-living nematodes and in the parasitic species. Haemonchus contortus. Nematode and mammalian ODC are reported to differ in subcellular localization, kinetics, and sensitivity to inhibitors. We cloned an H. contortus cDNA that encodes a full-length ODC (sequence data from this article have been deposited with the GenBank Data Library under Accession Nos. AF016538 and AF016891). This cDNA was functionally expressed in strains of Escherichia coli and Saccharomyces cerevisiae that lack ODC and are dependent upon exogenous PA for survival. Expression of nematode ODC reversed the PA-dependence phenotype of both microorganisms. The complemented yeast strain was used to develop a nutrient dependent viability screen for selective inhibitors of nematode ODC. The antiprotozoal drug stilbamidine isethionate was identified as active in this screen, but biochemical characterization revealed that this compound did not inhibit ODC. Instead, like other cationic diamidines, stilbamidine probably inhibits yeast S-adenosylmethionine decarboxylase. Nonetheless, the activity in the screen of the known ODC inhibitor difluoromethylornithine (DFMO) validates the concept that specific recombinant microorganisms can serve as the basis for extremely selective and facile screens. PMID- 9371083 TI - Plasmodium falciparum, P. vivax, and P. malariae: a comparison of the active site properties of plasmepsins cloned and expressed from three different species of the malaria parasite. AB - Aspartic endopeptidases (plasmepsins) have been implicated in the degradation of hemoglobin in the erythrocytic stage of infection by Plasmodium falciparum. To develop new targets for drug development, these enzymes have been isolated and cloned, expressed, and studied structurally and enzymatically. This study expands this approach to two other species of the malarial parasite, P. vivax and P. malariae. Expression of cloned genes from these species, utilizing methodology similar to that employed in the original reports on the enzymes from P. falciparum, has provided active enzymes for analysis by kinetic methods. We describe here studies of three enzymes, plasmepsin II from P. falciparum, and one plasmepsin from both P. vivax and P. malariae, utilizing oligopeptide substrates and low-molecular-weight inhibitors. These analyses provide new information on the properties of distinct regions of the active site cleft; such data can suggest strategies for drug design to inhibit these critical enzymes of the parasite. PMID- 9371084 TI - Entamoeba histolytica: computer-assisted modeling of phosphofructokinase for the prediction of broad-spectrum antiparasitic agents. AB - Pyrophosphate-dependent phosphofructokinase (PPi-PFK) is the rate-limiting glycolytic enzyme found in the pathogenic protists Entamoeba histolytica, Giardia lamblia, Toxoplasma gondii, Trichomonas vaginalis, and Naegleria fowleri. The enzyme differs significantly from ATP-dependent phosphofructokinases found in humans and as such represents an important drug target. Current therapy for infections caused by these pathogens is inadequate, especially for children, pregnant women, and the immune compromised. The development of more selective, safer agents in imperative, as parasitic infections are currently a significant health threat worldwide and will likely become increasingly common agents of disease in the future. For the purpose of designing drugs to treat parasitic infections, we have constructed a model of PPi-PFK from E. histolytica based on the three-dimensional structure of the ATP-dependent PFK from Bacillus stearothermophilus. The model was used with the computer program Dock 3.5 (University of California, San Francisco) to predict the binding of pyrophosphate and selected bisphosphonates to the enzyme. The predicted drug-enzyme interactions suggested that two of these compounds would be competitive inhibitors of pyrophosphate. These drugs were tested against E. histolytica and inhibited the growth of amebae in vitro. This class of compounds may have broad spectrum antiparasitic activity and, in the future, may facilitate the treatment of serious parasitic infections. PMID- 9371085 TI - Tritrichomonas foetus: a strategy for structure-based inhibitor design of a protozoan inosine-5'-monophosphate dehydrogenase. AB - Inosine-5'-monophosphate dehydrogenase (IMPDH) is an attractive drug target for the control of parasitic infections. The enzyme catalyzes the NAD-dependent oxidation of inosine monophosphate (IMP) to xanthosine monophosphate (XMP), the committed step in guanosine monophosphate (GMP) biosynthesis. We have determined the crystal structures of IMPDH from the protozoan parasite Tritrichomonas foetus in the apo form at 2.3 A resolution and the enzyme-XMP complex at 2.6 A resolution. The enzyme forms a cyclic (C4) homotetramer. The core domain of each monomer forms an eight-stranded parallel beta/alpha barrel with the enzyme active site at the C-termini of the barrel beta strands which lies near the center of the fourfold axis of the tetramer. While the electron-density for XMP in the complex structure is well-defined, the NAD cofactor and a nearby loop containing the catalytic cysteine (Cys-319) are disordered. This disorder at the active site suggests that a high degree of flexibility may be inherent to the catalytic function of IMPDH, making this area a difficult target for structure-based inhibitor design. Unlike IMPDHs from other species, the T. foetus enzyme coordinates the substrate phosphate with a single arginine guanidinium in the active site. Furthermore, a deep groove extends 8 A from the substrate phosphate away from the sugar. This structural uniqueness forms the basis of our efforts to design compounds that specifically inhibit the parasite enzyme. PMID- 9371086 TI - Leishmania major: molecular modeling of cysteine proteases and prediction of new nonpeptide inhibitors. AB - The crystal structures of papain, cruzain, and human liver cathepsin B were used to build homology-based enzyme models of a cathepsin L-like cysteine protease (cpL) and a cathepsin B-like cysteine protease (cpB) from the protozoan parasite Leishmania major. Although structurally a member of the cathepsin B subfamily, the L. major cpB is not able to cleave synthetic substrates having an arginine in position P2. This biochemical property correlates with the prediction of a glycine instead of a glutamic acid at position 205 (papain numbering). The modeled active sites of the L. major cpB and cpL were used to screen the Available Chemicals Directory (a database of about 150,000 commercially available compounds) for potential cysteine protease inhibitors, using DOCK3.5. Based on both steric and force field considerations, 69 compounds were selected. Of these, 18 showed IC50's between 50 and 100 microM and 3 had IC50's below 50 microM. A secondary library of compounds, originally derived from a structural screen against the homologous protease of Plasmodium falciparum (falcipain), and subsequently expanded by combinatorial chemistry, was also screened. Three inhibitors were identified which were not only effective against the L. major protease but also inhibited parasite growth at 5-50 microM. PMID- 9371087 TI - Plasmodium falciparum: kinetic interactions of WR99210 with pyrimethamine sensitive and pyrimethamine-resistant dihydrofolate reductase. AB - With emerging drug resistance in Plasmodium falciparum, novel antifolates effective against pyrimethamine-resistant and cycloguanil-resistant dihydrofolate reductase (DHFR) are in demand. Based on structural similarity to cycloguanil, it has been proposed that WR99210, and its metabolic precursor PS-15, exerts selective antimalarial activity by binding tightly to both drug-sensitive and drug-resistant DHFR. In the present study, Linweaver-Burk plots and Ackermann Potter plots reveal that both forms of malarial DHFR bind WR99210 at subnanomolar concentrations. It is not necessary to invoke an alternate target for WR99210 in P. falciparum. The present studies confirm that malarial DHFRs offer potential binding interactions in the folate-binding pocket distinct from those exploited by pyrimethamine and cycloguanil. These kinetic studies also provide a useful framework for the design and interpretation of future structural studies on drug resistant DHFR from P. falciparum. PMID- 9371088 TI - Trypanosoma brucei: effects of methoprene and other isoprenoid compounds on procyclic and bloodstream forms in vitro and in mice. AB - Drug therapy for the treatment of African sleeping sickness is limited by toxicity and resistance and in the last 50 years only one new drug has been introduced for the treatment of the human disease. We report that the juvenile hormone analog, methoprene, and several structurally related isoprenoid compounds kill Trypanosoma brucei in culture. Of the other isoprenoids tested, juvenile hormone III and mammalian retinoid X receptor ligands were the most potent trypanocides. Both the procyclic forms and the bloodstream trypomastigotes are killed by these compounds with LD50 values of 5-30 microM. Of the two methoprene stereoisomers, the EE form was the most active, suggesting that a protein target may be involved in mediating effects of these analogues against the parasite. Methoprene was not, however, able to clear trypanosomes from the blood of infected mice. Methoprene acid, the immediate downstream metabolite of methoprene, is not an effective anti-trypanosomal agent, suggesting that in the mice methoprene is converted to an inactive compound. Since methoprene and its analogues have low and well characterized toxicity in mammals these studies stress the importance of further exploring these isoprenoids as lead compounds for the treatment of African sleeping sickness. PMID- 9371089 TI - Site-directed mutagenesis of an acetylcholinesterase gene from the yellow fever mosquito Aedes aegypti confers insecticide insensitivity. AB - Insecticide resistance is a serious problem facing the effective control of insect vectors of disease. Insensitive acetylcholinesterase (AChE) confers resistance to organophosphorus (OP) and carbamate insecticides and is a widespread resistance mechanism in vector mosquitoes. Although the point mutations that underlie AChE insensitivity have been described from Drosophila, the Colorado potato beetle, and house flies, no resistance associated mutations have been documented from mosquitoes to date. We are therefore using a cloned acetylcholinesterase gene from the yellow fever mosquito Aedes aegypti as a model in which to perform site directed mutagenesis in order to understand the effects of potential resistance associated mutations. The same resistance associated amino-acid replacements as found in other insects also confer OP and carbamate resistance to the mosquito enzyme. Here we describe the levels of resistance conferred by different combinations of these mutations and the effects of these mutations on the kinetics of the AChE enzyme. Over-expression of these constructs in baculovirus will facilitate purification of each of the mutant enzymes and a more detailed analysis of their associated inhibition kinetics. PMID- 9371090 TI - Plasmodium falciparum: asparagine mutant at residue 108 of dihydrofolate reductase is an optimal antifolate-resistant single mutant. AB - The codon for serine residue 108 of the Plasmodium falciparum dihydrofolate reductase gene was replaced with those for the other 19 amino acids. Except for the Lys108 mutant, which was not expressed, all other substitutions yielded DHFR mutants which were expressed in Escherichia coli as inactive inclusion bodies. Nine of the mutants--Asn108, Thr108, Gly108, Ala108, Gln108, Cys108, Val108, Leu108, and Met108--yielded active DHFR upon refolding of the protein from the inclusion bodies. The remaining mutants--IIe108, Arg108, Pro108, Asp108, His108, Tyr108, Phe108, Trp108, and Glu108--did not exhibit detectable DHFR activity on refolding. The Asn108 mutant had almost unperturbed kinetic parameters but conferred resistance to pyrimethamine and cycloguanil; other active mutants showed poorer DHFR activity. We purified and characterized four mutants which produced highest DHFR activity, i.e., the Gln108, Gly108, Cys108, and Ala108 mutants. These mutant enzymes had kcat/K(m) values ranging from 7 to 22% of the wild-type enzyme. While DHFRs from Gly108, Cys108, and Ala108 mutants were as susceptible to pyrimethamine and cycloguanil as the wild type, the Gln108 mutation conferred high resistance to both inhibitors. Our data suggest that residue 108 is important for antifolate binding, and that the Ser108 to Asn108 mutation was selected in nature because of (i) the need for only a single base change, (ii) its good activity, and (iii) its resistance to antifolates. PMID- 9371091 TI - Resistance to insecticides in insect vectors of disease: est alpha 3, a novel amplified esterase associated with amplified est beta 1 from insecticide resistant strains of the mosquito Culex quinquesfasciatus. AB - Vector control programmes in many countries face the dual problems of parasite drug resistance and insecticide resistance in the insect vectors of the disease. Here we report for the first time a new esterase-based insecticide resistance mechanism in the filariasis vector Culex quinquefasciatus. The field collected COL strain of C. quinquefasciatus from Columbia was heterogeneous for organophosphorus insecticide resistance. On native polyacrylamide gels it had an elevated beta-naphthyl acetate specific esterase with the same Rf as that for the Est beta 1s involved in insecticide resistance in other strains of this mosquito species. After five generations of temephos insecticide selection, both the esterase specific activity with p-nitrophenyl acetate and the temephos LC50 values were increased, suggesting that elevation of esterase activity was the underlying mechanism of resistance. Western blots with antisera raised to Est alpha 2(1) and Est beta 2(1) from C. quinquefasciatus indicated that the COL strain had an elevated Est alpha 3 enzyme which co-migrated on native gels with Est beta 1. Southern blots indicated that an est alpha 3 gene was amplified in the COL strain and a Cuban mosquito strain (MRes), although the restriction digest patterns of the est beta 1 genes in these two strains are different. In contrast, the Californian TEMR strain, with the amplified est beta 1(1) gene, had no associated elevated Est alpha. Restriction digest patterns for COL and TEMR DNA suggest that they contain an identical est beta 1(1) gene, but our data suggest that the est alpha 3 gene occurs on the same amplicon as an est beta 1 gene although the genes are probably > 10 kb apart. Hence, either the COL strain has two est beta 1 genes or the est beta 1(1) amplicon in TEMR has been disrupted at some stage during the long colonisation of this strain and the amplified est alpha has been lost. PMID- 9371092 TI - The development of resistance to anthelmintics: a perspective with an emphasis on the antischistosomal drug praziquantel. PMID- 9371093 TI - Schistosoma japonicum GSH S-transferase Sj26 is not the molecular target of praziquantel action. AB - It has been suggested that Sj26, a Schistosoma japonicum GSH S-transferase, is the molecular target of the antischistosomal drug praziquantel (McTigue et al., 1995, J. Mol. Biol. 246, 21-27). We tested this hypothesis by asking two questions: (1) does praziquantel inhibit Sj26 activity with a variety of model substrates; and (2) does praziquantel prevent the binding to Sj26 of physiologically relevant nonsubstrate ligands? High concentrations of praziquantel (up to 500 microM) did not inhibit Sj26 activity using the model substrates 1-chloro-2,4-dinitrobenzene, 3,4-dichloronitrobenzene, or ethacrynic acid. Sj26 had no measurable activity with two higher molecular weight GSH S transferase substrates: 5-androsten-3,17-dione and sulfobromophthalein. We also assessed the ability of praziquantel to prevent the inhibition of Sj26 by a series of S-alkyl-GSH conjugates. The half-maximal inhibitory concentrations of S hexyl-GSH, S-octyl-GSH, and S-decyl-GSH (10, 10, and 5 microM, respectively) for Sj26 were not affected by up to 500 microM praziquantel. This suggests that praziquantel does not compete with GSH for Sj26 binding. In order to determine if praziquantel disrupts binding of nonsubstrate ligands to Sj26, we tested praziquantel for its ability to prevent the inhibition of Sj26 by both bilirubin and hematin. Praziquantel (100 or 500 microM) did not alter inhibition of Sj26 by 3 microM bilirubin, but partially protected Sj26 against inhibition by hematin (0.1 to 2.0 microM). Interestingly, in a similar reaction, 100 microM S-methyl GSH protected Sj26 from inhibition equally as well as praziquantel. Bovine serum albumin (5 microM) completely protected against inhibition by 1 microM hematin. These results indicate that although praziquantel partially protects Sj26 from hematin inhibition, this protection is neither specific to praziquantel nor physiologically relevant. Our results do not support the hypothesis that the mechanism of praziquantel action involves competitive inhibition of Sj26 catalytic activity or blocking binding of nonsubstrate ligands. We can, therefore, find no evidence that Sj26 is the molecular target of the antischistosomal activity of praziquantel. PMID- 9371094 TI - Efflux systems and increased trypanothione levels in arsenite-resistant Leishmania. AB - The mechanism of resistance to the metal arsenite has been studied and compared in L. mexicana, L. tropica, and L. tarentolae selected in a step by step manner for arsenite resistance. Amplification of the ABC transporter gene pgpA was found to be a frequent resistance mechanism in all species. Transfection of pgpA genes into different species indicated that both the origin of the pgpA gene and the recipient strain into which the gene is transfected seem important for resistance. An increase in the levels of trypanothione was also correlated with metal resistance in different Leishmania species. The mechanism used to increase the levels of trypanothione seems to differ, however, between the different species. This study points to a key role of transporters and thiol levels in metal resistance in Leishmania. PMID- 9371096 TI - Plasmodium fragile: efficacy of arteether (alpha/beta) against cerebral malaria model. PMID- 9371095 TI - Plasmodium falciparum: evaluation of lactate dehydrogenase in monitoring therapeutic responses to standard antimalarial drugs in Nigeria. AB - The correlation of P. falciparum lactate dehydrogenase (pLDH) activities and patent infections was evaluated for monitoring therapeutic responses and drug resistance in 70 patients with microscopically confirmed P. falciparum malaria in Nigeria. Each patient was treated with standard dosages of artemether (53 patients), chloroquine (7 patients), sulfadoxine-pyrimethamine (6 patients), or halofantrine (4 patients). Response of infection to treatment was monitored by microscopic examination of thick and thin blood smears, clinical symptoms, and levels of pLDH activities in blood products. pLDH activity was determined using an antibody capture technique and 3-acetyl pyridine adenine dinucleotide developed to enhance sensitivity of the enzyme detection. All patients treated with artemether were cured while 5 patients treated with chloroquine, 1 treated with sulfadoxine-pyrimethamine, and 2 treated with halofantrine suffered recrudescent infections after treatment. pLDH activity was detected in blood products obtained from patients with patent or recrudescent infections determined by microscopy and clinical symptoms. Levels of pLDH activities in whole blood and packed cells from the patients correlated with qualitative detection of parasites in blood smears and in patients with high gametocyte counts. Gametocyte counts in the patients after treatment ranged from 40 gametocytes/microliter of blood to 4923 gametocytes/microliter of blood. There is a consistent relationship between patent infection and pLDH activities that could easily be determined in whole blood and packed cells from the patients. Further development of the procedure will enhance its valuable application in clinical management of drug-resistant malaria in the endemic areas. PMID- 9371097 TI - Plasmodium: drug discovery and development--an industrial perspective. PMID- 9371099 TI - Who's reading your medical records? PMID- 9371098 TI - Molecular mechanisms underlying metronidazole resistance in trichomonads. PMID- 9371100 TI - Geriatrics photo quiz. Romberg's ataxia. PMID- 9371101 TI - Hypertension: the rediscovery of combination therapy. AB - Awareness and treatment of hypertension in the United States has been improving for older patients, but hypertension continues in many cases to be poorly controlled. Three options exist if initial therapy fails to achieve target blood pressure: upward drug titration, substituting another drug, or combination drug therapy. Combination therapy is the attempt to optimize blood pressure control by using two or more agents with additive or synergistic effects. Problems with this approach include noncompliance due to complicated regimens, adverse drug reactions, and the added expense of multiple medications. However, the newer fixed-dose combination products have been shown to offer improved blood pressure control, simplification of drug regimens, decreased adverse reactions, improved compliance, and cost-effectiveness. PMID- 9371102 TI - Rosacea: how to recognize and treat an age-related skin disease. AB - Rosacea is an age-related disorder of the central portion of the facial skin whose peak onset occurs in persons in their 40s and 50s. A chronic and progressive condition of flare-ups and remissions, rosacea can be disfiguring if left untreated. Rosacea can be characterized as having three stages. Target areas for all symptoms include the cheeks, nose, chin, or forehead. Rosacea resembles a number of other dermatologic conditions, particularly acne vulgaris. The combination of oral and topical antibiotic therapy usually brings about remission. The key is to recognize the early signs and clinical picture so that accurate diagnosis can be made and therapy and counseling instituted. PMID- 9371103 TI - Blistering eruption on the abdomen. PMID- 9371104 TI - Occult HIV infection: diagnosis and treatment of older patients. AB - The decrease in immune status that accompanies normal aging leaves individuals age 50 and older increasingly susceptible to the two main modes of HIV infection: sexual activity and blood transfusions. Although therapy for older HIV patients is essentially the same as for younger patients, knowledge of appropriate drug dosages and nutritional issues that influence the care of the older HIV patient is essential for physicians treating this population. Physicians need to recognize the clinical features of HIV-related dementia and opportunistic infections that distinguish it from other age-related illnesses such as Alzheimer's and Parkinson's disease. Known risk factors that affect older patients should influence physicians to routinely include HIV in their differential diagnoses. PMID- 9371105 TI - Keeping in shape: exercise fundamentals for the midlife patient. AB - The typical physiologic effects of aging on the musculoskeletal system can be impeded with regular exercise and diet. Common orthopedic problems in sedentary midlife patients are shoulder impingement, low back pain, and plantar fasciitis. Although the responsibility for maintaining an exercise program rests with the individual, the primary care physician can play an important role as coach, cheerleader, and respected advisor. The key is to encourage patients to initiate a program of regular, moderate exercise 30 minutes a day, three times a week, and to eat a balanced, nutritious diet. The best exercise and diet regimen is one that is custom-designed to accommodate the individual patient's needs and objectives. PMID- 9371106 TI - Future threats to residency education. PMID- 9371107 TI - A comparison of vascularized and nonvascularized bone grafts for reconstruction of mandibular continuity defects. AB - PURPOSE: This study compared vascularized and nonvascularized bone grafts for the reconstruction of segmental defects of the mandible. PATIENTS AND METHODS: The results in 39 patients having vascularized bone grafts (38 fibulas and one iliac crest) and 29 patients having nonvascularized bone grafts (26 iliac crest [22 corticocancellous block grafts, four cancellous bone grafts in a tray] and three rib grafts) for segmental mandibular reconstruction were evaluated in terms of overall success rate, total number of surgeries performed, total blood loss, total number of hospital days, and total number of hours in the operating room. RESULTS: Of 39 vascularized bone grafts, two failed (95% success rate), whereas of 29 nonvascularized bone grafts, seven failed (76% success rate). Failure for the nonvascularized bone grafts was closely correlated to the length of the defect. Nonvascularized bone graft patients underwent an average of one more surgical procedure for total reconstruction than vascularized bone graft patients, including osseointegrated implants. However, vascularized bone graft patients spent a mean of over 14 additional days in the hospital for all of their reconstructive procedures and an additional 3 hours in the operating room as compared with nonvascularized bone graft patients. Blood loss was similar in both groups (1,100 mL). Only 20% to 24% of patients in each treatment group have completed reconstruction to include osseointegrated implants. CONCLUSIONS: The success rate for vascularized bone grafting is high and is the treatment of choice when primary reconstruction is required, when the patient has been previously irradiated, or when simultaneous replacement of soft tissue is required. Vascularized bone grafts are also the treatment of choice for mandibular replacements over 9 cm in length. Nonvascularized bone grafts create a better contour and bone volume for facial esthetics and subsequent implant insertion, and may be the treatment of choice for secondary reconstruction of defects less than 9 cm in length. PMID- 9371108 TI - Computed tomography exclusion of osseous paranasal sinus injury in blunt trauma patients: the "clear sinus" sign. AB - PURPOSE: This prospective study was designed to assess the association of clear paranasal sinuses (no free fluid) as shown by facial computed tomography (CT) with the absence of fractures involving the paranasal sinus walls. PATIENTS AND METHODS: All facial CT scans performed during a 12-month period to rule out maxillofacial injury in blunt trauma patients were reviewed. The scans were made using 5-mm slice thickness and 4-mm table incrementation. They were assessed for the presence or absence of free paranasal sinus fluid (hemorrhage) and the presence and location of facial fractures. RESULTS: A total of 366 CT scans of the face were performed during the study. Among them, 180 scans (49%) were identified that showed no evidence of free paranasal fluid. Twenty-two (12%) of these 180 CT studies showed isolated nasal fractures (n = 13) or zygomatic arch fractures (n = 9). No patient without free paranasal sinus fluid had any midfacial fracture involving a paranasal sinus wall (P < .001 by Fischer exact test). CONCLUSION: The absence of free paranasal sinus fluid after facial trauma is a highly reliable criterion to exclude fractures involving the paranasal sinus walls. Other fractures involving osseous structures not contiguous with the paranasal sinus walls, such as nasal or zygomatic arch fractures, are not excluded. The CT "clear sinus" sign is a simple, rapid method to exclude paranasal sinus fractures. PMID- 9371109 TI - Aneurysmal bone cysts of the maxilla: a clinicopathologic review. AB - PURPOSE: This study evaluated the significant differences in clinicopathologic features of aneurysmal bone cyst in the maxilla and mandible. MATERIALS AND METHODS: A search of the literature showed 30 recorded maxillary cases, and these together with one previously unrecorded case formed the basis of the study. RESULTS: There were no differences in the age and sex incidence. Only two patients complained of pain, and no patient complained of tenderness. No patient gave a history of trauma. Swelling was present in virtually every patient. In seven cases, there was tooth mobility or migration of teeth. Two patients complained of paresthesia. Four patients presented with proptosis, two of whom complained of diplopia. The radiographic appearance of the aneurysmal bone cyst is suggestive but not diagnostic. CONCLUSION: Although these differences do not enable the clinician to make a definitive diagnosis before biopsy, they have important implications for management. PMID- 9371110 TI - Suicide in head and neck cancer patients. AB - PURPOSE: It has been well documented that patients with a diagnosis of cancer are at an increased risk of committing suicide. However, there is a paucity of literature on the risk of suicide in the head and neck cancer patient. The purpose of this investigation was to determine the incidence of suicide and expressed suicidal intent in a series of such cancer patients. PATIENTS AND METHODS: A retrospective chart review of 241 patients who were diagnosed with head and neck cancer at the University of Maryland Oral and Maxillofacial Surgery Oncology Division was done. RESULTS: Three patients were identified who committed suicide, 1.2% of the series. Two patients expressed suicidal intent, and four patients refused all treatment and counseling, preferring to die of their disease. CONCLUSIONS: Head and neck cancer patients have many of the same risk factors for suicide as patients with other forms of cancer. To reduce this risk, it is essential that the surgeon maintain good rapport with the patient, because this serves as a foundation for all other aspects of their therapy. In addition, these patients need to be fully evaluated for depression, hopelessness, pain, and other factors important in raising the possibility of suicide, and appropriate, aggressive management must be provided. PMID- 9371111 TI - Trismus and pain after removal of impacted lower third molars. AB - PURPOSE: This study evaluated trismus and pain after removal of impacted lower third molars and investigated whether these responses were related to difficulty of surgery. PATIENTS AND METHODS: A consecutive series of 104 patients, all of whom underwent removal of an impacted lower third molar under local surgery, was studied. Difficulty of surgery was evaluated on a modified version of the Parant scale: I, extraction with forceps only; II, extraction by ostectomy; III, extraction by ostectomy and coronal section; IV, complex procedures. Trismus was evaluated in terms of maximum interincisal distance (MID) 1 and 5 days after surgery. Pain was evaluated on the basis of reported analgesic use 1 and 5 days after surgery. RESULTS: Among group I subjects, mean day 1 MID did not differ significantly (P > .05) from mean presurgery MID, whereas mean day 1 MID in groups II, III, and IV was significantly lower than before surgery. In groups II, III, and IV, mean day 5 MID remained lower than before surgery. The proportion of group I patients using analgesics was significantly lower on both days 1 and 5 than the proportion of patients using analgesics in groups II, III, and IV. In all groups, the proportion of patients using analgesics dropped significantly between days 1 and 5. CONCLUSION: Trismus is less severe after simple (forceps only, grade I) extractions than after surgical extractions (grades II to IV). However, trismus severity after surgical extraction does not depend on difficulty of surgery. Pain, as revealed by reported analgesic use, is likewise less severe after simple extractions. Regardless of extraction type, pain declines between days 1 and 5 postsurgery. PMID- 9371112 TI - Survival analysis of endosseous implants in bone grafts used for the treatment of severe alveolar ridge atrophy. AB - PURPOSE: The aim of the current study was to evaluate the long-term results of endosseous implants placed into autogenous bone grafts in severely atrophic alveolar ridges. PATIENTS AND METHODS: A total of 871 implants were placed in 137 patients. The success rate was determined using survival analysis, log rank tests, and a cox regression analysis. RESULTS: Seventy-four implant failures were encountered in 23 patients. Most implants were lost because of a lack of osseointegration at the time of abutment connection or by asymptomatic loosening during the first months thereafter. The overall 1-year cumulative survival rate (CSR) was 83.4%, with a decrease to 67.8% after 5 years. The only parameter of prognostic relevance in the multivariate analysis of the whole study population was the patients' gender, with a significantly worse prognosis in female patients (5-year CSR, 62.3%). However, when the patients were divided into edentulous and partially edentulous jaws, a change was observed in the overall significance of the parameters introduced into the analysis. In edentulous patients, the maxilla appeared to over-rule all other parameters, with a 5-year cumulative survival rate of 48.8%, whereas the mandible presented a significantly higher rate of implant survival (5-year CSR, 89.3%). CONCLUSION: This study shows a poorer success rate in females than in males, probably because of differences in the quality of the bone grafts. PMID- 9371113 TI - A combined technique for correction of the prominent ear. AB - PURPOSE: The literature illustrates a large number of different techniques for the correction of the prominent ear, and the great variety available is indicative of how difficult it is to achieve satisfactory results in all cases. This report describes a procedure for successfully treating such patients. PATIENTS AND METHODS: Forty patients were treated with a surgical procedure creating a new anthelical plica based on the Stenstrom and Mustarde method and producing an anatomic cavity in the mastoid region where the concha can be repositioned according to the Furnas method. The tension of the "cartilage spring," which is a likely cause of relapse, was relieved by dissecting a triangular portion of cartilage from the root of the inferior crus. RESULTS: No major complications were observed with this technique and a good esthetic result was achieved in all cases. CONCLUSIONS: This surgical technique is suitable for correction of all cases of prominent ear. PMID- 9371115 TI - Results of reoperation after failed modified condylotomy. AB - PURPOSE: This retrospective study reports the reoperation rate for failure after modified condylotomy. MATERIALS AND METHODS: A consecutive series from each of two surgeons constituted the study group of 361 joints in 235 patients. Reoperation rates were calculated for all joints and by type of disc displacement. RESULTS: A second operation occurred in 4.2% of all joints. However, the cumulative rate of reoperation was 4.4%, because one of the joints required a third operation. Although the rate of reoperation varied (0% to 6.5%) according to the type of disc displacement, the differences were not statistically significant. All joints requiring reoperation had a displaced disc, and more than half had lost nearly all the joint space gained by the primary operation. CONCLUSION: The rate of reoperation for modified condylotomy is low. Risk factors for reoperation appear to be recurrent or residual disc displacement and loss of joint space after the first operation. Bilateral operation was not a risk factor. PMID- 9371114 TI - Presence of denatured hemoglobin deposits in diseased temporomandibular joints. AB - PURPOSE: The purpose of this study was to test the hypotheses that hemoglobin recovered by arthrocentesis of the superior joint space of symptomatic human temporomandibular joints (TMJs) is "old" hemoglobin that was not iatrogenically introduced by the arthrocentesis procedure and that it exists primarily in a non native or denatured conformation state that may be sufficient to catalyze a reaction leading to the formation of damaging free radicals. PATIENTS AND METHODS: Twelve patients diagnosed with a unilateral articular disk displacement with TMJ arthralgia were included in this study. A superior joint space arthrocentesis was performed in the affected TMJ, and outflow lavage volumes were collected in serial 2-mL fractions. alpha-Hemoglobin/albumin ratios were determined for each collected fraction by densitometric analysis of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). In addition, 3,3',5,5'-tetramethylbenzidine (TMB) assays were used to determine the conformation state of the recovered hemoglobin. RESULTS: High alpha hemoglobin/albumin ratios relative to that of serum (at least 10 times greater) were observed in several collected fractions of TMJ lavage fluid in all subjects studied. Because the tissue half-life of hemoglobin is significantly longer than that of albumin, these findings indicate that much of the hemoglobin recovered by arthrocentesis of symptomatic TMJs represents "old" hemoglobin that was present in the joint before the procedure. Furthermore, based on reactivity in the TMB assay, we estimate that up to 89% of the alpha-hemoglobin present in TMJ lavage fluid samples exists in a denatured state. CONCLUSIONS: These results indicate that a significant amount of hemoglobin recovered by arthrocentesis of symptomatic TMJs exists in a denatured state and was present in the joint before arthrocentesis. Recent studies suggest that denatured hemoglobin may contribute redox active iron that can catalyze a reaction, leading to the formation of damaging free radicals. Such a process may represent one of the earliest molecular events involved in the pathogenesis of degenerative TMJ disease. PMID- 9371116 TI - Pharmacology of agents used in the management of patients having skin resurfacing. AB - Many medications are used in the preparation, operative, and postoperative phases of skin resurfacing. This article reviews those medications that impact on laser, chemical peel, and dermabrasion surgery. Facial cosmetic surgeons must fully appreciate the "chemistry" of skin resurfacing. PMID- 9371117 TI - Effect of postoperative diet on condylar cartilage response to discectomy. AB - PURPOSE: Recent studies have shown that metabolic and structural changes occur in the condylar cartilage after surgical removal of the articular disc. There is some evidence that these structural changes are less pronounced in animals provisioned with a soft diet after disc removal. This study was initiated to assess whether a soft diet after discectomy in growing rats also results in alterations in the composition or metabolic activity of the matrix of the condylar cartilage. MATERIALS AND METHODS: In two identical experiments, 28 thirty-day-old female Sprague-Dawley rats underwent unilateral surgical removal of the articular disc (discectomy) and were then provisioned with either a soft, mushy diet or a diet of normal rat pellets. When they were killed 3 weeks later, the condylar cartilages were removed, weighed, pulse-labeled in organ culture with [35S]-sulfate for 2 hours, and analyzed for sulfated glycosaminoglycan (GAG) content and [35S]-sulfate uptake. RESULTS: As in previous studies, tissue weights and hydration were increased, and sulfated GAG content and [35S]-sulfate uptake decreased on the surgery side in animals fed a hard diet. Overall, fewer differences were present in the animals fed a soft diet, although tissue weights and hydration were still elevated on the discectomized side. Analysis of ratios of surgery/nonsurgery values in the hard diet versus the soft diet sample indicated that dietary consistency was a significant factor for tissue weights and [35S]-sulfate uptake, but not for hydration or sulfated GAG content. CONCLUSIONS: These data suggest that discectomy exerts a more pronounced effect on growing animals fed a hard diet, although some changes also persist after discectomy in animals fed a soft diet. PMID- 9371119 TI - Ultrastructural characteristics of the synovial membrane in osteoarthritic temporomandibular joints. AB - PURPOSE: This study analyzed the ultrastructural characteristics of the synovial membrane in various stages of osteoarthritis (OA) of the temporomandibular joint (TMJ), and developed a classification of this involvement based on these morphologic characteristics. PATIENTS AND METHODS: Synovial membrane biopsies were performed during unilateral arthroscopy in 40 patients. Thirty-one TMJs constituted the OA group; nine TMJs that were not involved by OA constituted the control group. During light microscopic (LM) examination, various variables were recorded and related to the duration of clinical signs and symptoms. Ten synovial membranes from osteoarthritic joints showing histologically visible pathologic changes in various stages and one control synovial membrane were selected for electron microscopic examination. RESULTS: The initial, early, and intermediate stages of synovial membrane involvement in TMJ OA were characterized by intima hyperplasia. In the initial and early stages, active and hypertrophic intimal cells are found. In the intermediate stage, an increased number of both intracytoplasmic and extracellular filaments was predominant. Fibrosis of the subintimal tissue was initiated by an increased number of active fibroblasts. The late stage of synovial membrane involvement in TMJ OA was characterized by a relatively normal synovial intima of normal thickness, whereas extensive fibrosis was seen in the subintimal tissues. CONCLUSIONS: Synovial membrane involvement in TMJ OA is characterized by an early proliferative phase with probable growth factor-mediated increases in the cellular activity of the synovial intima cells (resulting in hyperplasia and hypertrophy), of fibroblasts (resulting in increased production of collagen fibrils and fibrosis), and of endothelial cells (resulting in blood vessel growth and hypervascularity). The late phase is characterized by extensive fibrosis of the subintimal tissue, whether caused by sustained production of growth factors or by chronic venous insufficiency, with normal or little cellular activity. PMID- 9371118 TI - The origin of bone formed by heterotopic periosteal autografts. AB - PURPOSE: This study tested the hypothesis that a significant amount of the new bone produced by heterotopic periosteal autografts is derived osteoinductively because proliferating periosteal cells express the bone morphogenetic protein (BMP). MATERIALS AND METHODS: Rabbit ulnar and radial periosteum were autografted as free grafts (FGs) to the forelimb musculature, and as millipore diffusion chambers grafts (MDCGs) to the rectus abdominus muscle. The grafts were recovered at 3, 5, 7, 14, and 28 days postoperation, fixed in 4% paraformaldehyde, demineralized in 0.6N HCL, and 4.0 microns paraffin-embedded sections were immunostained with monoclonal antibody against recombinant human (rh) BMP-2. RESULTS: Sections from FGs recovered 5 to 28 days postoperatively exhibited cartilage and bone; fibrous tissue, cartilage, bone, and osteochondroid differentiated within MDCGs. Although BMP-2 was expressed by mesenchymal cells, osteoblasts, osteocytes, and osteoclasts, none of the MDCGs produced the osteoinductive signature of transmembrane bone formation. CONCLUSIONS: These observations indicated that the larger fraction of the new bone produced by heterotopic periosteal autografts is derived from the graft cells. PMID- 9371120 TI - Sinus augmentation for dental implants: the use of autogenous bone. AB - Autogenous bone has been the material of choice at our institution since 1983. The criteria for a successful graft in the sinus have been fulfilled based on functional stability in patients followed-up over 10 years in selected cases. Of 173 implants placed into autogenous bone grafted sinuses, 20 have been lost in four patients. Long-term follow-up is recommended for all graft materials used to support posterior maxillary restorations. PMID- 9371121 TI - Sinus augmentation for dental implants: the use of alloplastic materials. AB - The ability to augment the sinus floor has dramatically expanded the scope of implant dentistry. Clinical and scientific studies abound as to the efficacy of this procedure. The debate still ensues as to the best material to use for this augmentation, with autogenous bone, freeze-dried bone, xenografts, and alloplasts all being advocated. This article will substantiate through scientific and clinical studies, how the use of allplastic materials in sinus augmentation techniques can greatly reduce the morbidity and the expense of the procedure while predictably producing bone that has been shown to support dental implants in function for extended periods of time. PMID- 9371123 TI - Large radiolucent lesion of the mandibular condyle. PMID- 9371122 TI - Platelet gel: an autologous alternative to fibrin glue with applications in oral and maxillofacial surgery. AB - The preparation and use of platelet gel, an autologous formulation of fibrin glue, are described. The unique features of this biologic sealant are that it is derived from autologous blood collected in the immediate preoperative period by the anesthesiologist, it contains a high concentration of platelets, and it can be used in patients who are not candidates for blood bank donation. Platelet gel has been used successfully in the area of reconstructive oral and maxillofacial surgery in conjunction with ablative surgery of the maxillofacial region, mandibular reconstruction, surgical repair of alveolar clefts and associated oral antral/ oral-nasal fistulas, and adjunctive procedures related to the placement of osseointegrated implants. PMID- 9371124 TI - Open-mouth locking caused by unilateral elongated coronoid process: report of case. PMID- 9371125 TI - Cutaneous horns occurring on the head and neck region: report of four cases and review of the literature. PMID- 9371126 TI - Synovial chondrosarcoma of the temporomandibular joint: a case report. PMID- 9371127 TI - Hydroxyapatite deposition disease of the temporomandibular joint in a patient with renal failure. PMID- 9371128 TI - Basal cell adenoma: a case report. PMID- 9371129 TI - Arteriovenous hemangioma of the palate. PMID- 9371130 TI - Profuse bleeding and life-threatening airway obstruction after placement of mandibular dental implants. PMID- 9371131 TI - Management of the thalassemia-induced skeletal facial deformity: case reports and review of the literature. PMID- 9371133 TI - Glenoid fossa fracture and condylar penetration into the middle cranial fossa: report of a case and review of the literature. PMID- 9371132 TI - Antrolith associated with aspergillosis of the maxillary sinus: report of a case. PMID- 9371134 TI - Chondrosarcoma of the temporomandibular joint: a case report and review of the literature. PMID- 9371135 TI - Osseous hemangioma of the zygoma: a case report. PMID- 9371136 TI - Congenital granular cell tumor (congenital epulis) in the fetus: a case report. PMID- 9371137 TI - What determines competence? PMID- 9371139 TI - Advances in stroke management. PMID- 9371138 TI - So what's new. PMID- 9371140 TI - Overview of leukocyte adhesion. PMID- 9371141 TI - Cytokines, macrophages, and leukocytes in brain ischemia. PMID- 9371142 TI - Cytokines and reperfusion injury. PMID- 9371143 TI - Expression of inflammatory mediators and adhesion molecules in human atherosclerotic plaque. AB - The mechanisms that cause carotid atherosclerotic plaque to become symptomatic remain unclear. Evidence suggests that mediators of inflammation not only are instrumental in the formation of plaque but also may be involved in the rapid progression of atheromatous lesions, leading to plaque fissuring and intraluminal thrombosis. This article reviews the current evidence for the role of inflammatory mediators in atherosclerotic plaque production and maturation. It also includes studies performed in our laboratory to determine if known components of the inflammatory pathway, including cytokines and leukocyte adhesion molecules, are preferentially expressed on symptomatic versus asymptomatic carotid plaques. Carotid plaques from symptomatic and asymptomatic patients undergoing carotid endarterectomy with lesions of greater than 70% stenosis were snap-frozen and stored at -70 degrees C until analysis. Immunofluorescent studies were performed to measure endothelial expression of intercellular adhesion molecule-1 (ICAM-1). ICAM-1 expression was measured in a blinded fashion as percent of luminal endothelial surface of plaque sections. In situ hybridization also was performed to measure expression of message for tumor necrosis factor alpha (TNF-alpha) and ICAM-1 in the plaque by comparing mean optical density between the symptomatic and asymptomatic patients. There was increased expression of ICAM-1 on the endothelial surface in high-grade regions (28%) versus low-grade regions (11%), of plaques from symptomatic patients. There was also a trend toward greater expression of ICAM-1 in the high-grade region of symptomatic plaques versus the high-grade region of asymptomatic plaques. In situ hybridization revealed increased mRNA for TNF-alpha and ICAM-1 in the body of the plaque, preferentially in the high-grade region of plaques from symptomatic patients. The data obtained suggest that a local increase of endothelial inflammatory mediator expression correlates with the clinical setting of thromboembolic ischemia and may play a role in conversion of atheromatous plaque to a prothrombotic state. The data also indicate that this line of investigation deserves further exploration because it may be useful in identifying new mechanisms in patients at risk for stroke and in suggesting possible novel strategies for intervention. PMID- 9371144 TI - Antineutrophil strategies. PMID- 9371145 TI - Cerebral ischemia-reperfusion injury and adhesion. PMID- 9371146 TI - Non-neuronal responses to short-term occlusion of the middle cerebral artery. PMID- 9371147 TI - Antileukocyte adhesion therapy: preclinical trials and combination therapy. PMID- 9371148 TI - Risk factors, outcomes, and stroke subtypes for ischemic stroke. PMID- 9371149 TI - Infections as triggering factors for ischemic stroke. PMID- 9371150 TI - Infection, inflammation, and cerebrovascular ischemia. PMID- 9371151 TI - Brain and vascular imaging in acute ischemic stroke: the potential of computed tomography. PMID- 9371152 TI - Current therapeutic options for brain ischemia. PMID- 9371153 TI - rtPA in acute ischemic stroke: European perspective. PMID- 9371154 TI - rtPA in acute ischemic stroke: the North American perspective. PMID- 9371155 TI - Cerestat and other NMDA antagonists in ischemic stroke. AB - A wealth of experimental evidence demonstrates that cerebral ischemia causes excessive release of glutamate and that glutamate contributes to ischemic injury. Glutamate antagonism by any of several mechanisms can ameliorate the extent of infarction. These antagonists comprise noncompetitive blockers of the ion channel associated with the N-methyl-D-aspartate (NMDA) receptor [e.g., aptiganel (Cerestat)], competitive antagonists of the glutamate recognition site of the NMDA receptor (e.g., selfotel) or of the glycine recognition site (e.g., ACEA 1021, GV150526), antagonists at the polyamine site (e.g., eliprodil), and drugs that may interfere with glutamate release by sodium channel blockade as well as having other actions (e.g., lubeluzole, 619C89). Clinical experience suggests that although some NMDA antagonists are poorly tolerated at putative neuroprotective doses (e.g., selfotel), potentially neuroprotective plasma concentrations can be achieved in humans with others (e.g., aptiganel), though tolerable adverse effects are frequently observed. These clinical effects include hypertension (which is probably preferable to the hypotension seen with nimodipine and lifarizine), sedation, confusion or hallucinations and, at high doses, catatonia. Glycine antagonists may be associated with fewer adverse effects, but preclinical studies suggest that brain penetration may be low. Although recent studies with selfotel and eliprodil have been discontinued because of insufficient evidence for a satisfactory risk/benefit ratio, encouraging experience with aptiganel, magnesium, and glycine antagonists has prompted continued clinical trials with these agents. To be of sufficient size to detect a clinically useful improvement in outcome, these trials need to be large (600-1,000 patients). Present trials with aptiganel (Cerestat) are comparing the efficacy and tolerability of two doses vs. placebo in patients treated within 6 hours of ischemic stroke. Outcome is assessed by the modified Rankin Scale at 3 months. PMID- 9371156 TI - The concept of combination therapy in acute ischemic stroke. PMID- 9371157 TI - Antiplatelet drugs in secondary prevention of stroke: lessons from recent trials. PMID- 9371158 TI - Labour Government's tobacco spin spins them off track. PMID- 9371159 TI - Single daily doses of aminoglycosides. PMID- 9371160 TI - JNC VI: timing is everything. PMID- 9371161 TI - Blood transfusion and risk of non-Hodgkin lymphoma. PMID- 9371162 TI - Benefits of post-mastectomy radiotherapy. PMID- 9371163 TI - What is this thing called "randomise"? PMID- 9371164 TI - Effect of prophylactic amiodarone on mortality after acute myocardial infarction and in congestive heart failure: meta-analysis of individual data from 6500 patients in randomised trials. Amiodarone Trials Meta-Analysis Investigators. AB - BACKGROUND: There have been 13 randomised controlled trials of prophylactic amiodarone in patients with recent myocardial infarction (MI) or congestive heart failure (CHF). None of these was powered to detect a mortality reduction of about 20%. We undertook a meta-analysis, based on data from individual patients, to provide a more sensitive and accurate assessment of the benefits and risks of prophylactic amiodarone. METHODS: Individual data from the studies were abstracted according to a predefined protocol. The summary odds ratios were calculated according to standard methods. FINDINGS: There were eight post-MI and five CHF trials; nine trials were double-blind and placebo-controlled, and four compared amiodarone with usual care. 6553 patients were randomly assigned treatment, of which 78% were in post-MI trials and 22% in CHF trials. 89% had had previous MI. The mean left-ventricular ejection fraction was 31%, and median frequency of ventricular premature depolarisation 18 per h. Total mortality was reduced by 13% (odds ratio 0.87 [95% CI 0.78-0.99], p = 0.030) based on classic fixed-effects meta-analysis and by 15% (0.85 [0.71-1.02], p = 0.081) with the more conservative random-effects approach. Arrhythmic/sudden death was reduced by 29% (0.71 [0.59-0.85], p = 0.0003). There was no effect on non-arrhythmic deaths (1.02 [0.87-1.19], p = 0.84). There was no difference in treatment effect between post-MI and CHF studies. The risk of arrhythmic/sudden death in control-group patients was higher in CHF than in post-MI studies (10.7 vs 4.1%), and the best single predictor of risk of arrhythmic/sudden death among all patients was symptomatic CHF. The excess (amiodarone minus control) risk of pulmonary toxicity was 1% per year. INTERPRETATION: Prophylactic amiodarone reduces the rate of arrhythmic/sudden death in high-risk patients with recent MI or CHF and this effect results in an overall reduction of 13% in total mortality. PMID- 9371165 TI - Mortality from liver cancer and liver disease in haemophilic men and boys in UK given blood products contaminated with hepatitis C. UK Haemophilia Centre Directors' Organisation. AB - BACKGROUND: Most people with haemophilia who were treated with blood products before the introduction of virus-inactivation procedures were infected with the hepatitis-C virus (HCV). However, there is little quantitative information about the long-term effects on mortality of such infection. METHODS: We carried out a cohort study of mortality from liver cancer and liver disease in 4865 haemophilic men and boys in the UK. They were treated between 1969 and 1985 with blood products carrying a high risk of HCV infection, and were followed up from first recorded exposure to Jan 1, 1993. FINDINGS: Based on death-certificate information, mortality was 16.7 times higher than in the general population for liver disease (95% CI 12.5-22.0; 51 deaths), and 5.6 times higher (1.8-13.0; five deaths) for liver cancer. For men and boys with severe haemophilia who were not infected with HIV-1, the cumulative risks of death from chronic or unspecified liver disease or from liver cancer in the 25 years since first recorded exposure to high HCV-risk products were 1.4% (0.7-3.0) at all ages, and 0.10% (0.01-0.7), 2.2% (0.8-6.1), and 14.3% (4.5-40.9) for those with first recorded exposure at ages under 25, 25-44, and 45 or older. For those with haemophilia and HIV-1 infection, the corresponding risks were 6.5% (4.5-9.5) at all ages, and 3.8% (2.1 6.8), 17.1% (10.0-28.5), and 18.7% (6.4-47.6) in the three age-groups. In those with severe haemophilia, age-standardised all-cause mortality was stable during 1969-84 but increased during 1985-92 in both HIV-1-infected and HIV-1-uninfected groups. Among those not infected with HIV-1, the increase in all-cause mortality resulted largely from deaths attributed to chronic or unspecified liver disease or liver cancer in men aged over 45. INTERPRETATION: There is an emerging risk of mortality from liver disease and liver cancer in the UK haemophilia population in individuals both infected and uninfected with HIV-1, which probably results from infection with hepatitis C. PMID- 9371166 TI - Airways responsiveness and development and remission of chronic respiratory symptoms in adults. AB - BACKGROUND: Many patients with chronic obstructive lung disease show increased airways responsiveness to histamine. We investigated the hypothesis that increased airways responsiveness predicts the development and remission of chronic respiratory symptoms. METHODS: We used data from 24-year follow-up (1965 90) of 2684 participants in a cohort study in Vlagtwedde and Vlaardingen, Netherlands. Increased airways responsiveness was defined as a PC10 value (concentration of histamine for which challenge led to a 10% fall in forced expiratory volume in 1 s) of less than 8 mg/mL. Information on respiratory symptoms was collected by means of a standard questionnaire every 3 years. Logistic regression was used to control for age, area of residence, cigarette smoking status, and sex. FINDINGS: Participants with increased airways responsiveness (1281 observations) were more likely than those without increased airways responsiveness (5801 observations) to develop the following symptoms during any 3-year follow-up interval: chronic cough (odds ratio 1.9 [95% CI 1.2 2.9]), chronic phlegm (2.0 [1.3-3.0]), dyspnoea (2.3 [1.5-3.5]), asthmatic attacks (3.7 [2.2-6.1]), and persistent wheeze (2.7 [1.7-4.4]). The estimate of the odds ratio for the development of any of the six symptoms was 1.7 (1.2-2.3). Participants with increased airways responsiveness were less likely than those without this characteristic to show remission of these respiratory symptoms. The estimate of the odds ratio for the remission of any of the six symptoms was 0.42 (0.28-0.61). INTERPRETATION: These prospective analyses show that increased airways responsiveness is positively associated with the development of chronic respiratory symptoms and negatively associated with the remission of these symptoms in adults. PMID- 9371167 TI - Global assessment of El Nino's disaster burden. AB - BACKGROUND: Natural disasters have profound effects on health and require medical intervention as part of relief operations. The world's populations are becoming increasingly vulnerable to extreme weather events, which are responsible for most natural disasters. The El Nino Southern Oscillation (ENSO) is the most prominent global climate system associated with year-to-year weather variability and extreme events. We have estimated the burden on human health of natural disasters associated with ENSO. METHODS: We used time-series regression analysis of the relation between El Nino years and the annual rates of persons affected by natural disasters per 1000 population during 1964-93, globally and also by region and disaster type. Correlations between sea-surface temperature (SST) anomalies (index of ENSO) and the rates of persons affected by natural disasters per 1000 population were determined globally, by region and by disaster type. FINDINGS: The rate of persons affected by natural disasters worldwide is strongly associated with ENSO; rates are greater during the first El Nino year (p = 0.05) and the following year (p = 0.01) than in the pre-Nino year. The correlation between rates of persons affected by natural disasters and SST anomalies in the Eastern Pacific (a key ENSO indicator) is highest in the last quarter of the previous year (r = 0.53, p < 0.01). These associations are strongest in South Asia, the region where more than 50% of all disaster victims live. Worldwide, rates of persons affected by drought/famine (half of all disaster victims) and by volcanic eruptions show significant associations with the ENSO cycle, being highest in the post-Nino year and El Nino year, respectively, and being significantly associated with SST anomalies. INTERPRETATION: The strong relation between ENSO and populations affected by natural disasters can be described as a "natural disaster cycle". Determining the phase in this cycle, using SST from the Eastern Equatorial Pacific, could benefit disaster preparedness on a global scale, for South Asia in particular, and for all populations affected by drought/famine and volcanic disasters. PMID- 9371169 TI - A woman on the toilet. PMID- 9371168 TI - Preliminary evaluation of recombinant amino-terminal fragment of human bactericidal/permeability-increasing protein in children with severe meningococcal sepsis. AB - BACKGROUND: Meningococcal sepsis remains an important cause of morbidity and mortality. We hypothesised that children with severe meningococcaemia might benefit from inhibition of the inflammatory processes thought responsible for fulminant disease. rBPI21 is a recombinant, N-terminal fragment of human bactericidal/permeability-increasing protein, which kills meningococci and binds to and clears bacterial endotoxin, these being the primary inducers of the systemic inflammation. The aim of this study was to determine the safety and kinetics of rBPI21 in children with severe meningococcaemia and to make a preliminary assessment of clinical outcome. METHODS: In this open-label, dose escalation, phase I/II trial in severe meningococcaemia (Glasgow meningococcal prognostic septicaemia score [GMSPS] > or = 8), 26 patients aged 1-18 years, who had received their first dose of antibiotics no more than 8 hours earlier were given rBPI21 by infusion at total doses of 1.0, 2.0, and 4.0 mg/kg. FINDINGS: The patients had significantly raised plasma concentrations of bacterial endotoxin and cytokines. Peak and steady state BPI concentrations were comparable with pharmacokinetic data in healthy adults. All complications were compatible with the expected pattern for severe meningococcal sepsis. Only one patient died. This outcome was found to compare favourably with a predicted mortality of > or = 30% by GMSPS, > or = 15% by plasma endotoxin values, > or = 28% by plasma interleukin 6 concentrations, 29-49% by severity of coagulopathy, and 20% (11/54) by comparison with recent historical patients consecutively treated in participating centres before this study. INTERPRETATION: This, the first clinical trial or rBPI21, shows that rBPI21 can be safely administered to children with severe meningococcaemia and that the pharmacokinetics are consistent with patterns seen in healthy adults. Predicted mortality, on the basis of GMSPS, laboratory indices of inflammation and coagulopathy, and historical controls, was for between four and eight deaths. These findings have prompted a phase III randomised trial. PMID- 9371170 TI - Severe neonatal polycythaemia after third stage of labour underwater. PMID- 9371171 TI - Thalidomide in Crohn's disease. PMID- 9371172 TI - Angiotensin-converting-enzyme inhibitors in early pregnancy. PMID- 9371173 TI - Borrelia burgdorferi infection in patients with suspected acute myocardial infarction. PMID- 9371174 TI - Cord presentation with posterior placenta praevia. PMID- 9371175 TI - Occult cancer in patients with bilateral deep-vein thrombosis. PMID- 9371176 TI - Plasma adrenomedullin in diabetes. PMID- 9371177 TI - Varied effects of regular salbutamol on airway responsiveness to inhaled spasmogens. PMID- 9371178 TI - Spontaneous pneumothorax: predictable mini-epidemics? PMID- 9371179 TI - World Bank reports on priorities for HIV and AIDS. PMID- 9371180 TI - HIV-1 statistics bring good news for Uganda. PMID- 9371181 TI - Lower-limb arterial disease. PMID- 9371182 TI - Vaccine design, evaluation, and community-based use for antigenically variable infectious agents. AB - A major challenge for vaccine design and development, and for trials of new vaccines, is to tackle antigenically variable infectious agents. Here we outline a few general conceptual issues and then discuss new frameworks that are being developed to help understand how vaccination might change the distribution, abundance, and type of strains in a population. Herd Immunity is a key concept in population-based immunisation programmes and has to be considered in vaccine design and use even though it may cause a conflict between the needs of the individual versus those of the community. This issue is of increasing importance since once common infections are becoming rare due to effective vaccination. Concomitantly, adverse effects arising from immunisation are becoming more apparent as infection-induced morbidity declines to very low levels. Efficacy is widely regarded as a key criterion in vaccine design but duration of protection is of equal importance. Whether it is possible to produce effective vaccines to antigenically diverse pathogens remains uncertain but progress towards this goal will be enhanced by a better understanding of the population genetics of the target infectious agent facilitated by molecular epidemiological studies to assess the genetic constitution of pathogen populations and changes therein over time. PMID- 9371183 TI - An ancient British medical kit from Stanway, Essex. PMID- 9371184 TI - Boys' smoking and cigarette-brand-sponsored motor racing. PMID- 9371185 TI - Supermodels: stick insects or hourglasses? PMID- 9371186 TI - Florid plaques and new variant Creutzfeldt-Jakob disease. PMID- 9371187 TI - Thrombolytic therapy for acute ischaemic stroke. PMID- 9371188 TI - Thrombolytic therapy for acute ischaemic stroke. ECASS Study Group. PMID- 9371189 TI - Thrombolytic therapy for acute ischaemic stroke. PMID- 9371190 TI - Drug advertisements in medical journals. PMID- 9371191 TI - Submissiveness: protection or risk? PMID- 9371192 TI - Submissiveness: protection or risk? PMID- 9371193 TI - MTHFR 677C-->T mutation and neural-tube defects. PMID- 9371194 TI - WHO: where there is no vision, the people perish. PMID- 9371195 TI - WHO: where there is no vision, the people perish. PMID- 9371196 TI - Acanthamoeba keratitis and contact lens wear. PMID- 9371197 TI - Iodination of irrigation water and infant mortality. PMID- 9371198 TI - Iodination of irrigation water and infant mortality. PMID- 9371199 TI - Rationing of growth hormone: who reviews the experts? PMID- 9371200 TI - Rationing of growth hormone: who reviews the experts? PMID- 9371201 TI - Surgical management of pulmonary aspergilloma. PMID- 9371202 TI - Health technology assessment: time for a randomised controlled trial of the role of lung volume reduction surgery in the treatment of emphysema. The Lung Volume Reduction Surgery Trial Project Team. PMID- 9371203 TI - Management of childhood croup. PMID- 9371205 TI - What determines levels of passive smoking in children with asthma? AB - BACKGROUND: Children with parents who smoke are often exposed to high levels of environmental tobacco smoke, and children with asthma are particularly susceptible to the detrimental effects of passive smoking. Data were collected from parents who smoke and from their asthmatic children. The families are currently taking part in a randomised controlled trial to test an intervention designed to reduce passive smoking in children with asthma. This paper reports on the baseline data. Questionnaire data and cotinine levels were compared in an attempt to assess exposure and to identify factors which influence exposure of the children. The aim of the study was to identify the scope for a reduction in passive smoking by these children. METHODS: A sample of 501 families with an asthmatic child aged 2-12 years was obtained. Factors influencing passive smoking were assessed by interviewing parents. Cotinine levels were measured from saliva samples using gas liquid chromatography with nitrogen phosphorous detection. RESULTS: Cotinine levels in children were strongly associated with the age of the child, the number of parents who smoked, contact with other smokers, the frequency of smoking in the same room as the child, and crowding within the home. Parental cotinine levels, the amount smoked in the home, and whether the home had a garden also exerted an independent effect on cotinine levels in the children. CONCLUSIONS: Many children are exposed to high levels of environmental tobacco smoke and their cotinine levels are heavily dependent upon proximity to the parent who smokes. Parents who smoke have a unique opportunity to benefit their child's health by modifying their smoking habits within the home. PMID- 9371204 TI - Urban air pollution and emergency admissions for asthma in four European cities: the APHEA Project. AB - BACKGROUND: A study was undertaken to assess the combined association between urban air pollution and emergency admissions for asthma during the years 1986-92 in Barcelona, Helsinki, Paris and London. METHODS: Daily counts were made of asthma admissions and visits to the emergency room in adults (age range 15-64 years) and children (< 15 years). Covariates were short term fluctuations in temperature and humidity, viral epidemics, day of the week effects, and seasonal and secular trends. Estimates from all the cities were obtained for the entire period and separately by warm or cold seasons using Poisson time-series regression models. Combined associations were estimated using meta-analysis techniques. RESULTS: Daily admissions for asthma in adults increased significantly with increasing ambient levels of nitrogen dioxide (NO2) (relative risk (RR) per 50 micrograms/m3 increase 1.029, 95% CI 1.003 to 1.055) and non significantly with particles measured as black smoke (RR 1.021, 95% CI 0.985 to 1.059). The association between asthma admissions and ozone (O3) was heterogeneous among cities. In children, daily admissions increased significantly with sulphur dioxide (SO2) (RR 1.075, 95% CI 1.026 to 1.126) and non significantly with black smoke (RR 1.030, 95% CI 0.979 to 1.084) and NO2, though the latter only in cold seasons (RR 1.080, 95% CI 1.025 to 1.140). No association was observed for O3. The associations between asthma admissions and NO2 in adults and SO2 in children were independent of black smoke. CONCLUSIONS: The evidence of an association between air pollution at current urban levels and emergency room visits for asthma has been extended to Europe. In addition to particles, NO2 and SO2--by themselves or as a constituent of a pollution mixture--may be important in asthma exacerbations in European cities. PMID- 9371206 TI - Cough receptor sensitivity in children with acute and non-acute asthma. AB - BACKGROUND: Cough is a major symptom in some children with asthma. The relationship between cough and the severity of asthma is ill defined. A study was undertaken to test the hypotheses that, in children with asthma who cough as a major part of their asthma symptoms, cough receptor sensitivity (CRS) is heightened during an acute severe exacerbation of asthma but not in the non-acute phase and airway calibre or its change correlates with CRS. METHODS: Spirometric measurements and the capsaicin CRS test were performed on children admitted to hospital for an acute severe exacerbation of asthma. Nasal secretions were tested for viruses. The children were grouped into those who usually cough with asthma episodes and those who do not. The tests were repeated 7-10 days and 4-6 weeks later. The CRS outcome measure used was the concentration of capsaicin required to stimulate two (Cth) and five coughs (C5). RESULTS: The CRS of the group who coughed (n = 15) was significantly higher than those who did not cough (n = 16) (mean difference log Cth 0.77 mumol (95% CI 0.35 to 1.18), C5 0.72 mumol (95% CI 0.26 to 1.18)) during acute asthma but not after the exacerbation. CRS was not significantly different between groups based on the presence of a viral infection. Neither forced expiratory volume in one second (FEV1) nor its change correlated with CRS nor its change. CONCLUSIONS: In children with asthma CRS is heightened in acute severe asthma in the subgroup of children who have cough as a significant symptom with their asthma episodes. In acute and non-acute asthma CRS does not correlate with FEV1. PMID- 9371207 TI - Changes in neurokinin A (NKA) airway responsiveness with inhaled frusemide in asthma. AB - BACKGROUND: Inhaled frusemide exerts a protective effect against bronchoconstriction induced by several indirect stimuli in asthma which could be due to interference of airway nerves. A randomised, double blind, placebo controlled study was performed to investigate the effect of the potent loop diuretic, frusemide, administered by inhalation on the bronchoconstrictor response to neurokinin A (NKA) and histamine in 11 asthmatic subjects. METHODS: Subjects attended the laboratory on four separate occasions to receive nebulised frusemide (40 mg) or matched placebo 10 minutes prior to bronchial challenge with NKA and histamine in a randomised, double blind order. Changes in airway calibre were followed as forced expiratory volume in one second (FEV1) and responsiveness to the agonists was expressed as the provocative concentration causing a 20% fall in FEV1 from baseline (PC20). RESULTS: Compared with placebo, inhaled frusemide reduced the airway responsiveness to NKA in all the subjects studied, the geometric mean (range) values for PC20NKA increasing significantly (p < 0.001) from 130.3 (35.8-378.8) to 419.9 (126.5-1000) micrograms/ml after placebo and frusemide, respectively. Moreover, a small but significant change in airway responsiveness to histamine was recorded after frusemide, their geometric mean (range) PC20 values being 0.58 (0.12-3.80) and 1.04 (0.28-4.33) mg/ml after placebo and frusemide, respectively. CONCLUSIONS: The decrease in airway responsiveness to NKA after administration of frusemide by inhalation suggests that this drug may interfere with the activation of neurotransmission in human asthma. PMID- 9371208 TI - Total daily energy expenditure relative to resting energy expenditure in clinically stable patients with COPD. AB - BACKGROUND: An elevated resting energy expenditure (REE) commonly occurs in patients with chronic obstructive pulmonary (COPD). The purpose of this study was to investigate the effect of an increased REE on total daily energy expenditure (TDE) in 20 patients with COPD (19 men) with mean (SD) forced expiratory volume in one second of 37 (14)% predicted. METHODS: TDE was measured over a two week interval using doubly labelled water. Fat-free mass (FFM) was calculated from total body water assessed by deuterium dilution. REE was measured by indirect calorimetry using a ventilated hood system. RESULTS: The patients (10 men) with a significantly higher REE than those with a normal REE (median difference 205 kcal/ 24 h, p < 0.05) had a comparable TDE (hypermetabolic at rest: median 2593; range 2127-3083 kcal/24 h, normometabolic at rest: median 2629; range 2032-3179 kcal/ 24 h). There was no difference in mean daily heart rate (HR) between the groups (hypermetabolic at rest: median 92 (range 82-98), normometabolic at rest: median 98 (range 75-116) beats/min) or in the variation in the heart rate during the day. By means of multiple regression analysis it was shown that REE did not correlate significantly with TDE when FEM was taken into account. CONCLUSIONS: This study shows that there is no significant difference in free living TDE between clinically stable patients with COPD with a normal REE and those with an increased REE. The variation in TDE in patients with COPD appears to reflect differences in energy expenditure for activities, but not differences in REE. PMID- 9371209 TI - Selective inhibition of T cell proliferation but not expression of effector function by human alveolar macrophages. AB - BACKGROUND: Alveolar macrophages are thought to play an important part in regulating lung immune responses. While it is clear that human alveolar macrophages suppress T cell proliferation in vitro, the mechanisms by which this is achieved are not clear, nor is it known whether alveolar macrophages also inhibit other aspects of T cell function. METHODS: Peripheral blood mononuclear cells were stimulated with phytohaemagglutinin or house dust mite allergen, and cultured with variable numbers of autologous alveolar macrophages obtained by bronchoalveolar lavage from 20 normal subjects. RESULTS: Alveolar macrophages induced a reversible inhibition of T cell proliferation in response to both mitogen and allergen stimulation, with the latter being considerably more susceptible to inhibition. This was achieved via heterogenous mechanisms, involving both soluble factors derived from alveolar macrophages and cell-cell contact. Despite inhibiting proliferation, alveolar macrophages had little or no effect on T cell calcium flux, the characteristic changes in CD3, CD2, CD28 and interleukin-2 (IL-2) receptor expression which accompany normal T cell activation, and IL-2 and interferon gamma secretion. In contrast, alveolar macrophages inhibited the tyrosine phosphorylation of proteins which may be involved in IL-2 receptor-associated signal transduction. CONCLUSIONS: The immunoregulatory properties of alveolar macrophages are relatively selective, allowing T cell activation and cytokine secretion while inhibiting T cell proliferation within the lung. PMID- 9371210 TI - Diffusible component from the spore surface of the fungus Aspergillus fumigatus which inhibits the macrophage oxidative burst is distinct from gliotoxin and other hyphal toxins. AB - BACKGROUND: The fungus Aspergillus fumigatus, whose spores are present ubiquitously in the air, causes a range of diseases in the human lung. A small molecular weight (< 10 kD) heat stable toxin released from the spores of clinical and environmental isolates of A fumigatus within minutes of deposition in aqueous solution has previously been described. A key effect of the toxin was to inhibit the oxidative burst of macrophages as measured by superoxide anion release. It was hypothesised that the toxin was one of the commonly found A fumigatus hyphal toxins such as gliotoxin. This inhibitor may be an important factor which allows the fungus to colonise the lung. METHODS: The spore derived inhibitor was shown to inhibit the respiratory burst of rat alveolar macrophages, as measured by the generation of superoxide anion. Samples of the spore diffusate were subject to reversed phase high performance liquid chromatography (HPLC), thin layer chromatography (TLC), high performance thin layer chromatography (HPTLC), or organic extraction followed by TLC or HPLC to identify the presence of gliotoxin, fumagillin, helvolic acid, fumigaclavine-C, and aurasperone-C. Commercially obtained preparations of the toxins gliotoxin, fumagillin and helvolic acid and extracts enriched for fumigaclavine-C and aurasperone-C were used as internal and external standards and in the respiratory burst measurements. RESULTS: Gliotoxin, fumagillin, helvolic acid, fumigaclavine-C, and aurasperone-C were not detected in spore derived diffusate using PHLC or TLC. Using extraction procedures with solvents known to extract gliotoxin from A fumigatus culture supernatants, no gliotoxin was detected in the spore derived diffusate. Commercial gliotoxin, fumagillin, and helvolic acid or extracts enriched for fumigaclavine-C and aurasperone-C did not inhibit the oxidative burst of macrophages. CONCLUSIONS: The hypothesis that the spore derived toxin is one of the toxins derived from hyphae such as gliotoxin, helvolic acid, fumagillin, fumigaclavine-C, or aurasperone-C is not proved. The spore toxin may exert its effect through its ability to diffuse rapidly into the lung lining fluid, diminish the macrophage oxidative burst, and play a part in allowing A fumigatus to persist in the lung and manifest its well known pathogenic effects. PMID- 9371211 TI - Changing pattern of respiratory tuberculosis in the UK in adult patients from the Indian subcontinent. AB - BACKGROUND: Clinical observations over a 12 year period have suggested a changing pattern of adult respiratory tuberculosis in patients from the Indian subcontinent in two districts of the United Kingdom with a high incidence of tuberculosis. METHODS: Details of all patients for the period 1981-92 residing in the Newham and Blackburn districts aged 15 and over whose ethnic origin was from the Indian subcontinent (n = 1308) were analysed by stepwise logistic regression to determine the relationship between sputum smear positivity, sputum culture positivity, and isolated mediastinal lymphadenopathy, year of notification, age, sex, ethnic group (Indian or Pakistani), and whether the patient had visited the Indian subcontinent within the last three years. RESULTS: The proportion of cases who were smear positive rose over the 12 years of the study, as did the proportion of culture positive cases. The proportion with isolated mediastinal lymphadenopathy fell. These changes took place in both districts. They were not explained by demographic changes in age, sex, or ethnic group, nor was there evidence that smear and culture positivity increased in those who had recently visited India or Pakistan. CONCLUSIONS: The pattern of tuberculosis in adult patients originating from the Indian subcontinent has altered over time towards that seen in the white population in the UK. PMID- 9371212 TI - Recurrence of primary spontaneous pneumothorax. AB - BACKGROUND: Primary spontaneous pneumothorax (PSP) is a common clinical problem and its incidence is thought to be increasing. The risk of recurrence is high and various studies quote rates of 20-60%. Factors which may or may not predispose to recurrence have not yet been established. METHODS: In a study period of four years 291 cases with a diagnosis of pneumothorax were reviewed; 153 patients with PSP were included in the study. Their risk of recurrence was analysed with particular reference to the following variables: age, sex, height and body mass index (BMI) of the patient, the initial size of pneumothorax, the smoking status of the patient, and the primary form of treatment employed. Univariate analysis was carried out by chi 2 testing and multivariate analysis was calculated by a logistic regression model. RESULTS: A retrospective study of 275 episodes of PSP in 153 patients over a four year period confirmed a high incidence of recurrence (54.2%). PSP was twice as common in men as in women, though women were significantly more likely to develop a recurrence (chi 2 = 7.58, df = 1, p < 0.01). Male height was the second most important factor, and smoking cessation the only other variable which significantly influenced the risk of recurrence. CONCLUSIONS: Analysis of several potential risk factors revealed that recurrence was not related to the BMI of the patient, the initial treatment of the pneumothorax, nor to its size. Recurrence was more common in taller men and in women. Smoking cessation appeared to reduce the risk of recurrence. These findings are discussed in the context of the possible aetiology of spontaneous pneumothorax, recurrences, and the management thereof. PMID- 9371213 TI - Surgical treatment for pulmonary aspergilloma: a 28 year experience. AB - BACKGROUND: Pulmonary aspergilloma has been treated surgically for many years but the mortality rates of larger surgical series, varying from 7% to 23%, is not considered acceptable by today's standards. The authors report their experience in the surgical treatment of pulmonary aspergilloma and present a review of the literature. METHODS: Sixty seven patients who underwent thoracotomy for pulmonary aspergilloma from 1968 to 1995 were studied retrospectively by reviewing their medical records. RESULTS: The most common clinical presentation of pulmonary aspergilloma was haemoptysis which occurred in 61 patients (91.0%). Tuberculosis was the most common pre-existing disease, occurring in 54 patients (80.6%). The plain chest radiograph showed the typical "air-crescent" sign in 36 patients (53.7%). Systemic antifungal therapy neither palliated the clinical symptoms nor eradicated the aspergilloma, and transarterial embolisation was also unsuccessful. Surgery offered the only chance of cure for both unilateral and bilateral disease. Procedures varied from segmentectomy to pneumonectomy with most (61.4%) undergoing lobectomy. There was one death following surgery from pneumonia and 15 postoperative complications occurred in 12 patients-empyema (7), massive bleeding (3), bronchopleural fistula (2), wound infection (2), and Horner's syndrome (1). Postoperatively, most of the patients were symptom-free. CONCLUSIONS: With appropriate preoperative evaluation and judicious surgical technique, surgery is the preferred treatment for pulmonary aspergilloma, both for eradicating the tumour and for curing the underlying disease. PMID- 9371214 TI - Indications and outcome of surgery for pulmonary aspergilloma. AB - BACKGROUND: The indications and the outcome of surgery for pulmonary aspergilloma remain highly controversial. The short term and long term results of lung resection or cavernostomy in 24 patients with pulmonary aspergilloma are reported. METHODS: The case notes of 27 consecutive patients referred for surgical assessment for pulmonary aspergilloma at the Royal Brompton Hospital over the last 14 years were reviewed. Patients were categorised into four classes according to their fitness for lung resection and the severity of their symptoms. Severe symptoms were defined as life threatening haemoptysis or other symptoms requiring more than one hospital admission. Class I (n = 1), fit individual with mild or no symptoms; class II (n = 17), fit individuals with severe symptoms; class III (n = 1), unfit individual with no symptoms; and class IV (n = 8), unfit individuals with severe symptoms. Two asymptomatic patients and one on an IVOX pump were not accepted for surgery. Lung resection was performed in all 17 patients with class II disease, comprising segmentectomy only in five patients, lobectomy and segmentectomy in seven, and a completion pneumonectomy in five patients. Cavernostomy was performed in seven patients with class IV disease. RESULTS: Surgery was often complicated by prolonged air leakage and infection of residual space. There was no operative mortality in the group treated by resection whereas two of those who underwent cavernostomy died in the early postoperative period. All survivors were followed up for a median of 17 months (range 1-72 months); 19 were alive and had no symptoms attributable to aspergilloma. Late recurrence occurred in two patients in the cavernostomy group. The only late death occurred in the resection group five months postoperatively and was attributed to end stage renal disease. CONCLUSIONS: Lung resection in selected patients with complicated aspergilloma can be performed with low operative mortality. Cavernostomy is associated with high mortality and morbidity and should therefore only be performed in patients with life threatening symptoms who are unfit for lung resection. PMID- 9371215 TI - Absence of genetic linkage of chromosome 5q31 with asthma and atopy in the general population. AB - BACKGROUND: Clinical asthma is associated with increased serum total immunoglobulin E (IgE), atopy (skin prick test positivity to common aeroallergens), and bronchial hyperreactivity (BHR) to non-specific stimuli (positive methacholine challenge test). A region on chromosome 5q31-33 has been linked with increased total serum IgE and BHR. A study of the genetic linkage of this region with clinical asthma and atopy was therefore undertaken. METHODS: A polymorphic microsatellite marker in chromosome 5q31 (D5S399) was studied in 119 sibling pairs recruited from the general population who shared asthma, atopy, and/or BHR. Based on our population distribution of 13 different alleles, it was expected that by chance alone sibling pairs would share on average 1.24 alleles and that a significant excess would indicate genetic linkage. RESULTS: No evidence of linkage was found in 45 siblings concordant for asthma (shared alleles = 1.09, p = 0.95), in 103 sibling pairs with atopy (shared alleles = 1.18, p = 0.82), in 51 sibling pairs with BHR (shared alleles = 1.22, p = 0.62), or in 68 sibling pairs who shared atopy in the absence of BHR (shared alleles = 1.22, p = 0.61). A slight non-significant excess of shared alleles (1.44, p = 0.11) was observed in siblings who shared BHR without atopy. CONCLUSIONS: No evidence of genetic linkage of chromosome 5q31 with either clinical asthma or atopy was therefore detected in the population studied. Linkage between chromosome 5q and BHR needs further investigation. PMID- 9371216 TI - Effect of growth hormone on human alveolar macrophage oxidative metabolism. AB - BACKGROUND: Growth hormone (GH) has diverse immunological actions and has been shown to augment oxidative metabolism in rat peritoneal and porcine alveolar macrophages and both human and animal neutrophils. A study was performed to determine the effects of GH on human alveolar macrophages in vitro. METHODS: Macrophages were harvested from 10 patients undergoing bronchoalveolar lavage and incubated with 0, 10 and 100 nmol/ml GH for four hours. Oxidative metabolism was assessed by means of a fluorescent assay using FMLP and E coli as stimulants. Fluorescence was measured using flow cytometry. RESULTS: No difference in basal or stimulated oxidative metabolism was found between the GH and control groups. CONCLUSIONS: GH does not have a direct stimulatory action on human alveolar macrophages in vitro. However, this does not exclude an indirect effect in vivo. The results contrast with previous studies on animal alveolar macrophages. PMID- 9371218 TI - Bilateral diaphragmatic weakness: a late complication of radiotherapy. Commentary. PMID- 9371217 TI - Decline of FEV1 by age and smoking status: facts, figures, and fallacies. PMID- 9371219 TI - Bilateral diaphragmatic weakness: a late complication of radiotherapy. AB - Brachial plexus neuropathy is an unfortunate complication that sometimes follows radiotherapy to the axillary and supraclavicular regions. A patient is described who, 30 years after radiotherapy for Hodgkin's disease and more than 10 years after the development of radiation-induced bilateral brachial plexus neuropathy, presented with bilateral diaphragmatic weakness secondary to bilateral phrenic nerve weakness. Previous radiotherapy was the most probable cause of the condition. PMID- 9371220 TI - Right phrenic nerve palsy as a complication of indwelling central venous catheters. AB - Five cases are reported of patients who developed a raised right hemidiaphragm while an indwelling central venous catheter was in situ. The patients were being treated with protracted venous infusions of chemotherapy for colorectal carcinoma. All five patients had a chest radiograph following insertion of the Hickman line which showed normal diaphragmatic positions. A mean of 93 days later (range 55-134 days) elevation of the right hemidiaphragm was noted in these patients on repeat chest radiographs. Two of the patients had a right phrenic nerve palsy demonstrated by magnetic stimulation of the nerve. The remaining three patients had paradoxical motion of the right hemidiaphragm on sonography, but were unable to undergo studies of phrenic nerve function before death from metastatic disease. It is suggested that right phrenic nerve palsy is a late complication of an indwelling central venous catheter. PMID- 9371221 TI - Surgical management of Launois-Bensaude syndrome. PMID- 9371222 TI - Management of spontaneous pneumothorax. PMID- 9371223 TI - Management of spontaneous pneumothorax. PMID- 9371224 TI - Delays in the diagnosis and surgical treatment of lung cancer. PMID- 9371225 TI - Is asthma respiratory allergic disease? PMID- 9371226 TI - Gene amplification in Entamoeba histolytica. AB - We show here data suggesting that Entamoeba histolytica, the protozoan responsible for human amebiasis, presents DNA amplification in a fashion similar to that described for transformed mammalian cells. By transmission electron microscopy (TEM), we found linear, circular and concentric circular DNA molecules exhibiting the main events of the unscheduled DNA amplification process. Loops were formed after the recombination of two nonadjacent DNA regions, and bubbles appeared from the recombinant strands without involving the looped-out sequences. Bubbles grew up and underwent further replication rounds to produce a nested set of partially replicated circles. Multicircle complexes were also formed from putative replication origin without recombination of distant DNA regions. Clones derived from the strain HM1:IMSS exhibited different DNA contents, suggesting DNA amplification. The parental clone A and its daughter clone C2 differed in rDNA gene copy numbers, but this was observed only when total DNA was separated by pulse field gel electrophoresis, and no significant differences were detected in nuclear DNA. The dissection of the events observed by TEM led us to propose an onion skin model for gene amplification in E. histolytica. PMID- 9371227 TI - Vitamin D3 and ceramide reduce the invasion of tumor cells through extracellular matrix components by elevating protein phosphatase-2A. AB - Increasing phosphorylation reactions by protein kinase A (PKA) or reducing dephosphorylation reactions of protein phosphatase-2A (PP-2A) increases the invasiveness of Lewis lung carcinoma (LLC) cells, as measured by their capacity to traverse extracellular matrix (ECM)-coated filters. Metastatic LLC-LN7 variants have reduced PP-2A activity when compared to nonmetastatic LLC-C8 variants. Immunoblotting showed that this reduced level of PP-2A activity was not due to reduced levels of the PP-2A catalytic (C) subunit. The cellular PP-2A activity could be stimulated by addition of C2-ceramide to LLC-LN7 lysates, or by incubating cells with either C2-ceramide or with a noncalcemic analog of vitamin D3, which has previously been shown to stimulate the release of ceramide. These treatments to elevate PP-2A activity in metastatic LLC-LN7 cells resulted in a decline in their capacity to invade through select (ECM) components, particularly through vitronectin and laminin. Underscoring the importance of PP-2A in limiting the invasiveness of tumor cells was the demonstration that LLC-LN7 cell transfectants overexpressing the PP-2A C alpha subunit were less invasive through ECM components than the wild-type cells. Invasion by these cells was further reduced by additionally increasing PP-2A activity by incubation with C2-ceramide or the vitamin D3 analog. These results suggest a role of a vitamin D3/ceramide/PP-2A pathway in limiting the invasiveness of tumor cells through select ECM components. PMID- 9371228 TI - Regulation of the steps of angiogenesis by human head and neck squamous cell carcinomas. AB - Human head and neck squamous cell carcinoma (HNSCC) cell cultures were established to identify the angiogenic factors they produced and how these factors contribute to two steps of the angiogenic process: endothelial cell proliferation and migration. The HNSCC cells secreted vascular endothelial cell growth factor (VEGF), transforming growth factor-beta (TGF-beta) and prostaglandin E2 (PGE2), but only low levels of basic fibroblast growth factor. Both proliferation-stimulatory and -inhibitory cytokines were produced by the HNSCC cells, with VEGF promoting endothelial cell proliferation, prostaglandins having no effect and TGF-beta downregulating proliferation. Two methods were used to measure endothelial cell migration: migration into a wound in the endothelial cell monolayer and migration across a filter into lower compartments. HNSCC cell supernatants stimulated endothelial cell migration in both migration models. VEGF had no effect on the motility of endothelial cells. However, when TGF-beta activity in the HNSCC supernatants was neutralized with antibody or the production of prostaglandins by HNSCC cells was blocked with indomethacin, the migration-stimulatory activity in the HNSCC cell supernatants was diminished. Adding authentic PGE2 or TGF-beta 1 to endothelial cells mimicked the migration stimulatory activity of the HNSCC supernatants. Thus, HNSCC-derived VEGF is important in stimulating endothelial cell proliferation, while the antiproliferative effect of TGF-beta and the migration-stimulatory activity of TGF-beta and PGE2 suggest their having a role in the morphogenic processes of angiogenesis. PMID- 9371229 TI - Novel screening technique for dissemination potential of ovarian cancer cells to peritoneum. AB - Invasiveness to the peritoneum reconstituted with a mesothelial cell line and Engelbreth-Holm-Swam extract by metastatic cancer cell lines of the uterine cervix, endometrium, and ovary was always higher than that by primary cell lines. The invasiveness by metastatic ovarian cancer cell lines was significantly stronger than that by the other gynecological primary or metastatic cell lines. In the clinical ovarian cancers studied, cancer cells from the metastatic lesion were more invasive than those from the primary lesion. This suggests that metastatic ovarian cancer cells might inherently possess strong invasiveness to the peritoneum. The assay system used in the present study is useful in investigating the clinical behavior and basic biology of peritoneal dissemination. PMID- 9371230 TI - Collagen gene expression in the neomatrix of carcinoma of the breast. AB - Excessive deposition of extracellular matrix or neomatrix is a characteristic of desmoplastic invasive breast carcinomas. Type I and III collagens are abundant neomatrix components. Archival breast tissue sections were studied using 35S labeled cDNA probes for alpha 1(I) and alpha 1(III) procollagen and in situ hybridization. Among the 33 invasive breast cancers, hybridization was seen forming a gradient-like pattern in fibroblasts closest to tumor cells. In the 10 ductal carcinomas in situ studied, a ring-like pattern of hybridization was seen in proximity to the basement membrane zone. Adjacent normal and benign tissues did not demonstrate the patterns of hybridization described in malignant tissues. Gene expression for neomatrix interstitial collagens occurs before there is evidence of invasion in carcinoma of the breast. PMID- 9371231 TI - Node-positive breast cancer: axillary micrometastases, their incidence and some implications. AB - In node-positive breast carcinoma, the presence of tumour cells in the efferent vessels (EV) of the axillary nodes (positive EV status) was shown to be of poor prognosis in 1979. Later the presence of nodal micrometastases was also related to survival. This report describes a new subgroup in this system that is of potential therapeutic interest. It consisted of the 40% of the EV-positive cases with micrometastases (< 0.2 cm2) in their nodes, in addition to nodes with macrometastases. In them the difference in prognosis associated with EV status no longer held. Their prognosis did not differ markedly from that in the EV-negative patients. In the absence of such 'additional' micrometastases, the prognostic difference was still highly significant. There was also some indication that the presence of micrometastases consisting of embolic tumour growth alone may be associated with early death in EV-negative cases, in keeping with the prognosis in cases with lone micrometastases. PMID- 9371232 TI - In vivo binding of the radioiodinated peptide YIGSR on B16 melanoma cells. AB - It has been reported that metastatic melanoma cell lines selectively bind in vitro with the synthetic laminin pentapeptide tyrosyl-isoleucyl-glycyl-seryl arginine (YIGSR). The aim of this study was to investigate whether the same peptide can bind on melanoma cells in vivo as well. Iodine-125-labeled YIGSR was administered to B16 melanoma-bearing animals. Microscopic autoradiography of tumor and organ sections taken 24 h after peptide administration showed that the peptide did accumulate on the surface of certain tumor cells. The peptide binding cells were frequent in metastatic sites and tumors grown for 24 days and rare in tumors grown for 10 days. A similarly radiolabeled control pentapeptide (peptide DRLKY) did not bind to any tumor cell. It is suggested that the YIGSR binding tumor cells may represent a distinct melanoma cell population with a high metastatic potential. PMID- 9371233 TI - Synthesis of 5,6-dihydro-4-hydroxy-2-pyrones as HIV-1 protease inhibitors: the profound effect of polarity on antiviral activity. PMID- 9371235 TI - Synthesis and antimalarial activity in vitro and in vivo of a new ferrocene chloroquine analogue. AB - The antimalarial activities of ferrocenic compounds mimicking chloroquine and active upon chloroquine-resistant strains of Plasmodium falciparum were evaluated. Four 7-chloro-4-[[[2-[(N,N-substituted amino)methyl]ferrocenyl]methyl]amino]quinoline derivatives have been synthesized; one of them, 1a, showed high potent antimalarial activity in vivo on mice infected with Plasmodium berghei N. and Plasmodium yoelii NS. and was 22 times more potent against schizontocides than chloroquine in vitro against a drug resistant strain of P. falciparum. PMID- 9371234 TI - Potent and selective 1,2,3-trisubstituted indole NPY Y-1 antagonists. PMID- 9371236 TI - Design, synthesis, and cocrystal structure of a nonpeptide Src SH2 domain ligand. AB - The specific association of an SH2 domain with a phosphotyrosine (pTyr) containing sequence of another protein precipitates a cascade of intracellular molecular interactions (signals) which effect a wide range of intracellular processes. The nonreceptor tyrosine kinase Src, which has been associated with breast cancer and osteoporosis, contains an SH2 domain. Inhibition of Src SH2 phosphoprotein interactions by small molecules will aid biological proof-of concept studies which may lead to the development of novel therapeutic agents. Structure-based design efforts have focused on reducing the size and charge of Src SH2 ligands while increasing their ability to penetrate cells and reach the intracellular Src SH2 domain target. In this report we describe the synthesis, binding affinity, and Src SH2 cocrystal structure of a small, novel, nonpeptide, urea-containing SH2 domain ligand. PMID- 9371237 TI - Discovery of a novel, selective, and orally bioavailable class of thrombin inhibitors incorporating aminopyridyl moieties at the P1 position. AB - A novel class of thrombin inhibitors incorporating aminopyridyl moieties at the P1 position has been discovered. Four of these thrombin inhibitors (13b,c,e and 14d) showed nanomolar potency (Ki 0.8-12 nM), 300-1500-fold selectivity for thrombin compared with trypsin, and good oral bioavailability (F = 40-76%) in rats or dogs. The neutral P1 was expected to increase metabolic stability and oral absorption. Identification of this novel aminopyridyl group at P1 was a key step in our search for a clinical candidate. PMID- 9371238 TI - 1,4-disubstituted anthracene antitumor agents. AB - Three different types of 1,4-disubstituted anthracenes were synthesized, and their cytotoxicity in a panel of tumor cells was compared with that of the corresponding 9,10-disubstituted anthracenes. The panel contained human myeloma, melanoma, colon, and lung cancer cells and sensitive and multidrug-resistant murine L1210 leukemia cells. These compounds had [[(dimethylamino)ethyl]amino]methyl, N-[(dimethylamino)ethyl]carbamoyl, and carboxaldehyde (4,5-dihydro-1H-imidazol-2-yl)hydrazone side chains. The 1,4 diamide was more potent across the tumor panel than the corresponding 9,10 isomer, but the 1,4-diamine and the 1,4-hydrazone were less potent than their 9,10-isomers. Although the 1,4-hydrazone was active against P388 leukemia in mice, it was inactive against L1210 leukemia. Within each pair of compounds, the one with greater average potency against tumor cells gave a greater increase in the transition melt temperature of DNA. PMID- 9371239 TI - Betidamino acid scan of the GnRH antagonist acyline. AB - Strong clinical evidence suggests that GnRH antagonists will replace GnRH agonists in a number of indications because of their ability to inhibit gonadotropin secretion as long as an adequate concentration of the analogue is present in the circulation whereas superagonists will take approximately 2 weeks to desensitize the gonadotrophs. Until recently, antagonists were either too weak and/or would release histamine. Azaline B {[Ac-D2Nal1,D4Cpa2,D3Pal3, 4Aph5(atz),D4Aph6(atz),ILys8,DAla10] GnRH} and long-acting members of the azaline family {Ac-D2Nal-D4Cpa-D3Pal-Ser-4Aph(X)-D4Aph(Y) -Leu-ILys-Pro-DAla-NH2}, however, appear to be promising drug candidates. Because these antagonists tend to form gels (due to the formation of beta-sheet structures) and, as a result, are not readily amenable to formulation for long-term delivery, we have investigated ways of increasing hydrophilicity while retaining high potency and lack of histamine releasing activity. Betidamino acids (a contraction of "beta" position and "amide") are N'-monoacylated (optionally, N'-monoacylated and N-mono or N,N'-dialkylated) aminoglycine derivatives in which each N'-acyl/alkyl group may mimic naturally occurring amino acid side chains or introduce novel functionalities. We have used unresolved N alpha-Boc,N'alpha-Fmoc-aminoglycine, and N alpha-Boc,N'alpha-(CH3)Fmoc-aminoglycine as templates for the introduction of betidamino acids in acyline (Ac-D2Nal-D4Cpa-D3Pal-Ser-4Aph(Ac)-D4Aph(A c)-Leu Ilys-Pro-DAla-NH2), a long acting member of the azaline B family, to test biocompatibility of these betide derivatives. Diastereomeric peptides could be separated using RP-HPLC in most cases. Biological results obtained in vitro (binding affinity to rat pituitary gland membranes) and in vivo (rat antiovulatory assay, AOA) indicate in most cases small differences in relative potencies (< 5-fold) between the D- and L-nonalkylated betidamino acid-containing acylines. Importantly, most betide diastereomers have high affinity for the GnRH receptor and were equipotent with acyline in the AOA. Greater differences in affinity and potency between diastereomers were observed after introduction of a methyl group on the side chain nitrogen ("beta" position) of the same analogues, with one of the diastereomer having an affinity and a potency in the AOA equivalent to that of acyline. These results suggest that chirality at the alpha carbon coupled to side chain orientation is important for receptor recognition. The duration of action of some of the most potent analogues was also determined in the castrated male rat in order to measure the extent (efficacy and duration of action) of inhibition of luteinizing hormone release. Data suggest that introduction of a betidamino acid results in reduction of duration of action. Also, introduction of betidamino acids results in peptides with increased hydrophilicity (as determined by elution times on C18 silicas at pH 7.3) compared to that of the parent compound. N'-Methyl substitution results in parallel increase in retention times on C18 silicas as expected. PMID- 9371240 TI - 1-[(omega-aminoalkyl)amino]-4-[N-(omega-aminoalkyl)carbamoyl]-9-oxo-9, 10 dihydroacridines as intercalating cytotoxic agents: synthesis, DNA binding, and biological evaluation. AB - A series of DNA-intercalating potential antitumor agents, 1-[(omega aminoalkyl)amino]-4-[N-(omega-aminoalkyl)carbamoyl]-9-oxo-9, 10-dihydroacridines, has been prepared by aminolysis of the corresponding 4-[N-(omega aminoalkyl)carbamoyl]-1-chloro derivative with a suitable omega-aminoalkylamine. The noncovalent DNA-binding properties of these bis-functionalized compounds have been examined using a combination of fluorometric and thermal denaturation techniques and are compared with the behaviors for established DNA intercalants and cationic minor groove ligands. The results indicate that (i) the agents are considerably more DNA-affinic than less functionalized acridinones, with 'apparent' binding constants of (0.1-2.1) x 10(7) and (0.3-7.5) x 10(7) M-1 at pH 5 and 7, respectively, (ii) overall affinity is sensitive to both the length of the flexible side chain and the complexity of the attached amine substituents, and (iii) the pendant side chains effect a switch to moderate AT-preferential binding. In vitro cytotoxic potencies toward six tumor cell lines broadly parallel the observed DNA affinities, although poor correlation is evident for certain compounds. The octanol/water partition coefficients have been also calculated, but there is no correlation with cytotoxicity values. Two highly DNA affinic analogs, 10 and 13, have been identified with a useful broad spectrum of cytotoxic activity. PMID- 9371241 TI - Synthesis and biological evaluation of 4-(hydroxyalkyl)estradiols and related compounds. AB - A series of synthetic estrogens containing hydroxyalkyl side chains at the C-4 position of the A ring were designed as metabolically stable analogs of 4 hydroxyestradiol, a catechol estrogen. These synthetic steroids would facilitate investigations on the potential biological role of catechol estrogens and also enable further examination of the structural and electronic constraints on the A ring in the interaction of estrogens with the estrogen receptor. Catechol estrogens are implicated as possible causative agents in estrogen-induced tumorigenesis. 4-Hydroxyestradiol has weaker affinity for the estrogen receptor and exhibits lower estrogenic activity in vivo; on the other hand, the catechol estrogens are prone to further oxidative metabolism and can form reactive intermediates. This report describes the synthesis and initial biochemical evaluation of 4-(hydroxyalkyl)estrogens and 4-(aminoalkyl)estradiols. The 4 (hydroxyalkyl)estrogens were prepared by oxidative hydroboration of 4 alkenylestradiols. The alkenylestradiols were obtained via a Stille cross coupling between a MOM-protected 4-bromoestradiol and an alkenylstannane. The (4 aminoalkyl)estrogens were prepared from the hydroxyalkyl derivatives with phthalimide under Mitsunobu conditions. The substituted estradiols were evaluated for estrogen receptor binding activity in MCF-7 human mammary carcinoma cells, and 4-(hydroxymethyl)estradiol 1 exhibited the highest affinity with an apparent EC50 value of 364 nM. The relative activities for mRNA induction of the pS2 gene in MCF-7 cell cultures by the 4-(hydroxyalkyl)estrogens closely parallel the relative binding affinities. 4-(Hydroxymethyl)estradiol 1 did not stimulate the growth of MCF-7 cells at concentrations up to 1 microM. Thus, 4 (hydroxymethyl)estradiol 1 exhibited similar estrogen receptor affinity as the catechol estrogen, 4-hydroxyestradiol, and may prove useful in the examination of the biological effects of 4-hydroxyestrogens. PMID- 9371242 TI - N6-cyclopentyl-3'-substituted-xylofuranosyladenosines: a new class of non xanthine adenosine A1 receptor antagonists. AB - The present study explores the C-3' site of the 3-deoxy-3-xylofuranosyl ring of nucleoside analogues with an adenine or N6-cyclopentyladenine (CPA) base moiety and evaluates the effect on adenosine receptor affinity. Two series of sugar modified adenosines, i.e., 3'-amido-3'-deoxyadenosines and 3'-amidated 3' deoxyxylofuranosyladenines, were synthesized and tested for their affinity at A1 and A2a receptors in rat brain cortex and rat striatum, respectively. The modest affinity found in the "xylo series" prompted us to synthesize the corresponding N6-cyclopentyl derivatives, which proved to be well accommodated by the A1 receptors with potencies in the lower nanomolar range. This represents a new perspective in the purinergic field. The absence of a GTP-induced shift, i.e., the ratio between the affinities measured in the presence and absence of 1 mM GTP indicates an antagonistic behavior of this new class of CPA analogues. PMID- 9371243 TI - Simple analogues of anthralin: unusual specificity of structure and antiproliferative activity. AB - Fifty-nine simple analogues of the antipsoriatic agent, anthralin, have been prepared by modifying the positions of the 1,8-hydroxyl groups, replacement of the hydroxyl groups, substitution at the oxygen functions, introduction of additional functional groups into various positions of the anthracenone nucleus, or removal of particular structural elements. The compounds were evaluated for their antiproliferative action against human keratinocytes and inhibition of the generation of leukotriene B4 in polymorphonuclear leukocytes, which may be useful to resolve the proliferative and inflammatory aspects of psoriasis, respectively. Even though many anthracenones were more potent inhibitors of leukotriene biosynthesis than anthralin, none of the compounds was substantially more effective as this drug in suppressing keratinocyte cell growth. There is an absolute requirement for two hydroxyl groups peri to a hydrogen bond acceptor such as a keto or an imino group for high potency. In addition to further delineating the nature of the pharmacophore for this class of compounds, also naphthalenedione with a peri hydroxyl group was identified as a pharmacophore with antiproliferative activity against keratinocyte growth. PMID- 9371244 TI - 4-hydroxy-5,6-dihydropyrones. 2. Potent non-peptide inhibitors of HIV protease. AB - The 4-hydroxy-5,6-dihydropyrone template was utilized as a flexible scaffolding from which to build potent active site inhibitors of HIV protease. Dihydropyrone 1c (5,6-dihydro-4-hydroxy-6-phenyl-3-[(2-phenylethyl)thio]-2H-pyran-2-one) was modeled in the active site of HIV protease utilizing a similar binding mode found for the previously reported 4-hydroxybenzopyran-2-ones. Our model led us to pursue the synthesis of 6,6-disubstituted dihydropyrones with the aim of filling S1 and S2 and thereby increasing the potency of the parent dihydropyrone 1c which did not fill S2. Toward this end we attached various hydrophobic and hydrophilic side chains at the 6-position of the dihydropyrone to mimic the natural and unnatural amino acids known to be effective substrates at P2 and P2'. Parent dihydropyrone 1c (IC50 = 2100 nM) was elaborated into compounds with greater than a 100-fold increase in potency [18c, IC50 = 5 nM, 5-(3,6-dihydro-4-hydroxy-6-oxo 2-phenyl-5-[2-phenylethyl)thio] -2H-pyran-2-yl)pentanoic acid and 12c, IC50 = 51 nM, 5,6-dihydro-4-hydroxy-6-phenyl-6-(2-phenylethyl)-3- [(2-phenyl-ethyl)thio]-2H pyran-2-one]. Optimization of the 3-position fragment to fill S1' and S2' afforded potent HIV protease inhibitor 49 [IC50 = 10 nM, 3-[(2-tert-butyl-5 methylphenyl)sulfanyl]-5,6-dihydro-4 -hydroxy-6-phenyl-6-(2-phenylethyl)-2H-pyran 2-one]. The resulting low molecular weight compounds (< 475) have one or no chiral centers and are readily synthesized. PMID- 9371245 TI - Design and synthesis of imidazoline derivatives active on glucose homeostasis in a rat model of type II diabetes. 1. Synthesis and biological activities of N benzyl-N'-(arylalkyl)-2-(4',5'-dihydro-1'H-imidazol-2'-yl)piperazines . AB - The physiopathology of non-insulin-dependent diabetes mellitus is associated with a dysfunction in the regulation of insulin secretion. The alpha 2-adrenoceptors have been reported to be involved in this alteration, although alpha 2 antagonists containing an imidazoline ring may stimulate insulin secretion independently of alpha 2-adrenoceptor blockage. Recently, a new "imidazoline binding site" involved in the control of K(+)-ATP channels in the B cell has been proposed. In the course of searching for new antidiabetic agents, 1-alkyl-2 (4',5'-dihydro-1'H-imidazol-2'-yl)-4-benzylpiperazines, 1-benzyl-2-(4',5'-dihydro 1'H-imidazol-2'-yl)-4-alkylpiperazines, and 1-benzyl-2-(4',5'-dihydro-1'H imidazol-2'-yl)-4-benzylpiperazines have been designed and evaluated as potential adrenoceptor antagonists. Pharmacological evaluation was performed in vivo using glucose tolerance tests performed on a rat model of type II diabetes obtained by injection of a low dose (35 mg/kg) of streptozotocin (STZ). For some compounds, binding experiments were performed on alpha 2 adrenoceptors and I1 and I2 imidazoline-binding sites. The biological and physicochemical data have been combined with molecular modeling studies to establish structure-activity relationships. The most active compound was 1-(2',4'-dichlorobenzyl)-2-(4',5' dihydro-1'H-imidazol-2'-yl)- 4-methylpiperazine (7f); intraperitoneal administration (100 mumol/kg) of 7f strongly improved glucose tolerance in STZ diabetic rats. This effect seemed at least partly mediated by a significant increase of insulin secretion. Other compounds of the same family (7b, 16f, 23b) have also shown potent activity. We found no correlation between in vivo antihyperglycemic properties and in vitro affinities for alpha 2-adrenoceptors or I1, and I2 binding sites. These compounds can be considered as antihyperglycemic agents potentially useful for treatment of type II diabetes and are currently under complementary investigation. PMID- 9371246 TI - Antimuscarinic 3-(2-furanyl)quinuclidin-2-ene derivatives: synthesis and structure-activity relationships. AB - A series of 25 derivatives of the muscarinic antagonist 3-(2-furanyl)quinuclidin 2-ene (4) was synthesized and evaluated for muscarinic and antimuscarinic properties. Substitution at all three positions of the furan ring has been investigated. The affinities of the new compounds were determined by competition experiments in homogenates of cerebral cortex, heart, parotid gland, and urinary bladder from guinea pigs using (-)-[3H]-3-quinuclidinyl benzilate as the radioligand, and the antimuscarinic potency was determined in a functional assay on isolated guinea pig urinary bladder using carbachol as the agonist. Several of the novel derivatives displayed high muscarinic affinities. Whereas the affinity of lead compound 4 for cortical muscarinic receptors is moderate (Ki = 300 nM), it is much higher for the 5-methyl (48; Ki = 12 nM), 5-ethyl (52; Ki = 7.4 nM), 5 bromo (33; Ki = 6.4 nM), and 3-phenyl (49; Ki = 2.8 nM) substituted derivatives. The substituent-induced increases in affinity do not appear to be additive as a 5 bromo-3-phenyl (54), and a 5-methyl-3-phenyl (55) substitution pattern only slightly increases affinity (Ki = 1.55 and 2.39 nM, respectively). The conformational preferences of the 3-phenyl (49) and 5-phenyl (51) derivatives were studied by X-ray crystallography and molecular mechanics calculations. Because of the observed high affinity of 49, a series of 16 meta- and para substituted analogues of 49 was synthesized and tested. The m-hydroxy derivative (68) exhibited more than 10-fold improvement in affinity as compared to 49. The structure-activity relationships of the new series are well described with QSAR and CoMFA models. PMID- 9371247 TI - Synthesis and biological activity of a series of potent fluoromethyl ketone inhibitors of recombinant human calpain I. AB - Calpain I, an intracellular cysteine protease, has been implicated in the neurodegeneration following an episode of stroke. In this paper, we report on a series of potent dipeptide fluoromethyl ketone inhibitors of recombinant human calpain I (rh calpain I). SAR studies revealed that while calpain I tolerates a variety of hydrophobic groups at the P1 site, Leu at P2 is preferred. However, the nature of the N-terminal capping group has a significant effect on the inhibitory activity of this series of compounds. Compound 4e [(1,2,3,4 tetrahydroisoquinolin-2-yl)carbonyl-Leu-D,L-Phe-CH2F+ ++], having a tetrahydroisoquinoline containing urea as the N-terminal capping group, is the most potent dipeptide fluoromethyl ketone inhibitor of calpain I (with a second order rate constant for inactivation of 276,000 M-1 s-1) yet reported; tripeptide 4k (Cbz-Leu-Leu-D,L-Phe-CH2F) is equipotent. A number of compounds presented in this study displayed excellent selectivity for calpain I over cathepsins B and L, two related cysteine proteases. Compounds which exhibited good inhibitory activity in the assay against isolated rh calpain I also inhibited intracellular calpain I in a human cell line. Thus, in an intact cell assay, compounds 4e and 4k inhibited calpain I with IC50 values of 0.2 and 0.1 microM, respectively. Finally, we also disclose the first example of fluorination of a dipeptide enol silyl ether to generate the corresponding dipeptide fluoromethyl ketone. PMID- 9371248 TI - Synthesis and evaluation of (S)-4-(3-(2'-[11C]isopropylamino)-2-hydroxypropoxy) 2H-benzimidazol -2-one ((S)-[11C]CGP 12388) and (S)-4-(3-((1'-[18F] fluoroisopropyl)amino)-2-hydroxypropoxy) -2H- benzimidazol-2-one ((S)-[18F]fluoro CGP 12388) for visualization of beta-adrenoceptors with positron emission tomography. AB - The beta-adrenoceptor antagonist (S)-[11C]CGP 12177 (4-(3-(tert-butylamino)-2 hydroxypropoxy)-2H-benzimidazol -2[11C]- one) is a generally accepted radioligand for cardiac and pulmonary PET studies. The synthesis of [11C]CGP 12177 is a laborious and often troublesome procedure. Therefore, (S)-CGP 12388 (4-(3 (isopropylamino)-2-hydroxypropoxy) -2H-benzimidazol-2-one), 5, the isopropyl analogue of CGP 12177, has been labeled with carbon-11 in the isopropyl group via a reductive alkylation by [11C]acetone (3) of the corresponding (S)-desisopropyl compound 2. The fluoro-substituted analogue of (S)-CGP 12388 was prepared by reacting 2 with [18F]fluoroacetone (4). (S)-[11C]CGP 12388 (5) was easily prepared via a one-pot procedure. The radiochemical yield of (S)-[11C]CGP 12388 (600-800 Ci/mmol, EOS) was 18% (EOB) with a total synthesis time of 35 min, whereas (S)-[18F]fluoro-CGP 12388 (6) (> 2000 Ci/mmol, EOS) was synthesized in 105 min with a radiochemical yield of 12% (EOB). Biodistribution studies in rats demonstrated specific binding to beta-adrenoceptors of (S)-[18F]fluoro-CGP 12388 and (S)-[11C]CGP 12388 in lung and heart. The lungs were clearly visualized with PET studies of rats. Total/nonspecific binding at 60 min postinjection was 5.6 for (S)-[11C]CGP 12388 and 2.0 for the (S)-18F compound. Due to its facile synthetic procedure and in vivo data, (S)-[11C]CGP 12388 is a promising beta adrenoceptor ligand for clinical PET. PMID- 9371249 TI - Synthesis and structure-activity profiles of A-homoestranes, the estratropones. AB - 2-Methoxyestradiol, a mammalian metabolite of estradiol, has reported antiangiogenic activity which has been proposed to be mediated through interaction at the colchicine binding site on the tubulin monomer. Subsequent structure-activity studies of 2-methoxyestradiol have yielded highly potent steroidal inhibitors of tubulin polymerization. In an effort to probe the scope of binding at the colchicine binding site and the nature of the relationship between 2-methoxyestradiol and colchicine, a series of colchicine/2 methoxyestradiol hybrids was synthesized. These A-homoestrane hybrid systems, collectively termed estratropones, possessed an A-ring tropone system with the keto functionality at either the C-2, C-3, or C-4 position of the steroid nucleus. The estratropones were evaluated for their ability to inhibit the polymerization of tubulin using an in vitro purified bovine brain assay. Most of these hybrids inhibit polymerization with greater potency than either of the natural products. The most potent of these congeners possessed an approximate 5 fold enhancement of the activity of colchicine for the inhibition of tubulin polymerization. alpha-Substituents on the tropone ring showed varied effects on the activities for the two classes of estratropones studied in this regard, the C 3 oxo and the C-4 oxo species. The 3-substituted 4-oxoestratropones exhibited antitubulin activity according to Cl approximately Br > OCH3, whereas the 4 substituted 3-oxoestratropones exhibited activity according to OCH3 > Br approximately Cl. It is unclear if these substituent factors are purely electronic or steric effects or if the substituent operates indirectly by altering the conformation of the nonplanar troponoid ring. The estratropones represent a new class of tubulin binding agents with potential antiangiogenic utility. PMID- 9371250 TI - Design, synthesis, and biochemical evaluation of phosphonate and phosphonamidate analogs of glutathionylspermidine as inhibitors of glutathionylspermidine synthetase/amidase from Escherichia coli. AB - Three phosphapeptides designed to mimic two distinct tetrahedral intermediates formed during either the synthesis or hydrolysis of glutathionylspermidine (Gsp) were synthesized and evaluated as inhibitors of the bifunctional enzyme Gsp synthetase/amidase. While the polyamine-containing phosphapeptides were determined to be potent and selective inhibitors, they selectively inhibit the synthetase activity over the amidase domain. A phosphonate-containing tetrahedral mimic is a reversible mixed-type inhibitor of Gsp synthetase with an inhibition constant of 6 microM for the inhibitor binding to the free enzyme (Ki) and 14 microM for the inhibitor binding to the enzyme-substrate complex (Ki'). The corresponding phosphonamidate is a slow-binding inhibitor with a Ki of 24 microM and a Ki* (isomerization inhibition constant) of 0.88 microM. A non-polyamine containing phosphonamidate exhibits no significant inhibition of the synthetase or amidase activity. PMID- 9371252 TI - A proposal to mobilize public opinion in support of the National Institutes of Health. Commentary. PMID- 9371251 TI - Retinoic acid conjugates as potential antitumor agents: synthesis and biological activity of conjugates with Ara-A, Ara-C, 3(2H)-furanone, and aniline mustard moieties. AB - In a dual targeting approach, to explore the ability of tretinoin (all-trans retinoic acid) to behave as a covalent carrier for cytotoxic entities, conjugates of retinoic acid with a few representative molecules, being important examples of antitumor pharmacophores (i.e., nucleoside analogues and alkylating agents), have been synthesized and tested for their cytostatic and differentiating activity. All compounds were stable to in vitro hydrolysis in human plasma and more lipophilic than the parent compounds, thus consenting enhanced uptake into the cells. Among the nucleoside analogues the Ara-C derivatives 3 and 6 and the Ara-A derivative 7 proved the most cytostatic (IC50 < 0.32 microgram/mL) resulting from 25- to > 144-fold more active (Ara-A derivatives) or at least as equally active (Ara-C derivatives) as compared to the parent nucleosides. Compound 3, endowed with a highly lipophilic silyl moiety at the 3' and 5' positions, showed the highest differentiating activity (54% and 44% differentiated HL-60 cells at 0.2 and 0.05 microgram/mL respectively). With regard to the retinoic acid conjugates of alkylating agents, compound 10 was the most cytostatic agent (IC50 < 0.32 microgram/mL) and the most potent differentiating agent (33-34% at 0.32 and 0.08 microgram/mL). These structures may also be regarded as analogs of either retinoic acid or the cytotoxic compound. PMID- 9371253 TI - Genetics of histocompatibility. AB - Molecular studies of the major histocompatibility complex region, its genes, and its products are progressing in a number of different directions, and this progress is becoming of increasing interest not only to immunologists but also to geneticists and clinicians. Here I select only certain aspects of this field, stressing the biological importance of a few recent developments. This review concentrates on two topics of clinical importance and where important recent progress is reported: the "revolution" of HLA genotyping for histocompatibility matching in transplantation and the elucidation of a genetic disease of gene regulation, primary major histocompatibility complex class II deficiency (or bare lymphocyte syndrome). PMID- 9371254 TI - The molecular basis of X-linked agammaglobulinemia, hyper-IgM syndrome, and severe combined immunodeficiency in humans. AB - The molecular basis for X-linked agammaglobulinemia, hyper-IgM syndrome, and severe combined immunodeficiency was recently identified. In X-linked agammaglobulinemia the molecular defect was found to reside in the gene encoding a novel cytoplasmic tyrosine kinase (bpk, atk, or btk) expressed by B and myeloid cells. This kinase belongs to a new subfamily of tyrosine kinases that contains SH1, SH2, and SH3 domains. A defect in the murine homologue of this kinase has been shown to be responsible for X-linked immunodeficiency in mice. Currently, the role of btk in B- and myeloid cell signaling is unknown. The molecular defect in X-linked hyper-IgM syndrome has been shown to reside in the gene encoding the T-cell activation protein gp39 (CD40L, TRAP). This protein binds to its counter receptor, CD40, on B cells and has been shown to participate in T-cell-dependent B-cell help leading to B-cell proliferation and isotype switching. X-linked severe combined immunodeficiency patients were found to have defects in the gene encoding the gamma-chain of the interleukin-2 receptor. This chain of the interleukin-2 receptor is constitutively expressed by T cells and is involved in the formation of high and intermediate affinity interleukin-2 receptor complexes. These two interleukin-2 receptor complexes are responsible for mediating interleukin-2-dependent signals. PMID- 9371255 TI - Viral activity in early HIV disease. AB - The commonly accepted paradigm for the natural history of HIV disease has been an acute burst of virus replication followed by years of viral quiescence. A terminal phase of virus activity is accompanied by gradual immunologic failure. Recent studies of the tissue localization of HIV and developments in virus quantitation have prompted a revision of this model. Viral latency has been shown to be only a relative concept by the demonstration of virus accumulation in tissue sites during early disease and quantifiable circulating levels of virus throughout the course of HIV infection. The primacy of HIV infection in AIDS has been further reaffirmed by these studies, but new questions as to its pathogenic effects have been raised. PMID- 9371256 TI - Genetic programs of myeloid cell differentiation. AB - A great body of evidence indicates that hematopoietic cytokines and the availability of their cognate receptors at the cell membrane surface of myeloid progenitors play crucial roles in lineage commitment and differentiation. Little is known of how these receptors couple to downstream signal transduction pathways to convert the extracellular signal into a change in the genetic program. Lineage switching of myeloid progenitors suggests that a limited number of key regulatory genes govern lineage commitment. Several transcription factors have been implicated as key regulators, positive or negative, of myeloid lineage commitment and terminal differentiation. Evidence for an autocrine mechanism involving interleukin-6 in coupling late stages of myeloid cell proliferation to cell maturation is presented. Elucidation of molecular events that take place in cell cycle control associated with growth arrest and differentiation would further enhance the understanding of the genetic programs that govern myeloid cell development. PMID- 9371257 TI - Mast cell and basophil development. AB - Mast cells and basophils express certain remarkable similarities in mediator content, histochemical characteristics, and function. Yet a large body of evidence now indicates that the mast cell and basophil lineages are distinct. Stem cell factor, the ligand for the receptor encoded by c-kit, is a major growth factor for mast cells in both rodent and primate species, and can modulate mast cell secretory function. Moreover, abnormalities affecting the stem cell factor receptor or stem cell factor might contribute to some cases of mastocytosis or mast cell neoplasms. By contrast, basophils can develop independently of stem cell factor, and are not as sensitive as mast cells to the effects of stem cell factor on mediator secretion. In addition, the cytokine interleukin-3 greatly augments the production of human basophils, but has little or no growth promoting activity for human mast cells. PMID- 9371258 TI - Chemoattractant receptors. AB - One of the first responses in the inflammatory process is the migration of cells along gradients of specific chemical signals, the chemotactic factors. Chemotactic factors are referred to as ligands that bind to structurally specific cell surface receptors. Binding of the ligand to its receptor initiates a series of coordinated events leading to cell migration, adhesion, and activation. This review describes recent advances in structure-function relationships of chemotactic factor receptors on human leukocytes as well as potential areas for pharmacological intervention. PMID- 9371259 TI - Biological advances and clinical applications of Fc receptors for IgG. AB - There are three classes of Fc gamma receptor proteins, Fc gamma RI (CD64), Fc gamma RII (CDw32), and Fc gamma RIII (CD16), which are encoded by at least eight genes. In this review we summarize some of the biological advances in the Fc gamma receptors during the past year, specifically: 1) identification of genes and their products; 2) regulation of gene expression and modulation of receptor number; 3) cellular functions and mechanisms of signal transduction; 4) ligand binding and the role of polymorphisms; and 5) soluble Fc gamma receptors. We also highlight the direct clinical applications of this Fc gamma receptor research. PMID- 9371260 TI - Ras-related GTP-binding proteins and leukocyte signal transduction. AB - Many aspects of leukocyte function are regulated by both heterotrimeric and Ras related GTP-binding proteins, but there is little definite information about their roles in the specialized processes utilized by leukocytes for cell killing. Recent progress in understanding the regulation of the phagocyte NADPH oxidase by the Rac GTP-binding proteins provides a basis for defining the operational characteristics of one such phagocyte system. It is clear from various studies that the activity of the NADPH oxidase can be modulated through the regulation of the GTP-GDP state of Rac. Proteins exist in leukocytes able to modify GTP-binding protein function in this manner, and their activity may be regulated by signals generated on phagocyte stimulation. Proteins of the Ras superfamily are likely to be involved in a variety of normal phagocyte functions through their ability to modulate the assembly of actin filaments, direct vesicle trafficking and fusion, and so forth. PMID- 9371261 TI - Actin polymerization and leukocyte function. AB - The coordinated remodeling of the filamentous actin-based microfilamentous cytoskeleton via regulated polymerization and depolymerization of globular and filamentous actin is required for polymorphonuclear leukocyte motile functions including locomotion, shape change, phagocytosis, and adhesion. Significant new observations on the structure and function of distinct filamentous actin pools in polymorphonuclear leukocytes, the mechanisms of chemotactic peptide-mediated actin polymerization, the role of filamentous actin in polymorphonuclear shape change in suspension and on a surface, the identification and characterization of rare patients with polymorphonuclear motile defects and actin dysfunctions, and regulation of actin reorganizations by actin regulatory proteins, the phosphorylation or dephosphorylation states of proteins, and the second messengers--the phosphoinositides--were reported in the past year. These observations form the basis for an improved understanding of the cellular and molecular role of actin assembly in polymorphonuclear function and are the subject of this review. PMID- 9371262 TI - Eicosanoids in leukocyte function. AB - Agonist-induced release of arachidonic acid from membrane phospholipids and its oxygenation by specific enzymes to generate bioactive eicosanoids represent an important series of events that is thought to play a pivotal role in both physiologic and pathologic responses. Research during the past year confirmed and extended our knowledge of lipoxygenase activation and assembly of the 5 lipoxygenase complex in leukocytes. Many of the key enzymes and proteins in the arachidonic acid signaling cascade were identified, and rational drug design is in progress to interact with these targets. The role of transcellular biosynthesis in leukotrienes, lipoxins, and other novel eicosanoids is emerging as an important theme in eicosanoid formation in multicellular events including thrombosis, inflammation, and atherosclerosis. Moreover, new bioactions were identified for both leukotrienes and lipoxins. Counterregulatory roles demonstrated for lipoxins suggest that these compounds may serve as endogenous chalones generated via lipoxygenase- and cell-cell interactions. PMID- 9371264 TI - Penetration, retention, intracellular localization, and antimicrobial activity of antibiotics within phagocytes. AB - The deficiency in cell-mediated immunity that is the hallmark of AIDS has led to a resurgence of infections with tubercle bacilli and other intracellular pathogens, and to renewed attention to the mechanisms by which antibiotics penetrate and are retained within phagocytic leukocytes. We review here recent studies of these mechanisms and the activity of different classes of antibiotics against microbial pathogens growing within or ingested by neutrophils and mononuclear phagocytes. PMID- 9371263 TI - Leukocyte-derived antimicrobial proteins. AB - Survival in environments teeming with microbes depends on efficient mechanisms of host defense. Antimicrobial peptides and polypeptides in granules of leukocytes (eg, neutrophils) provide an important arm of first-line defense against invading microorganisms. Recent studies have broadened the scope and settings in which these proteins may function and, in at least one case, are leading to the development of a recombinant product that may provide a novel therapy for bacterial diseases when endogenous defenses are limiting. PMID- 9371266 TI - Leukocytes. PMID- 9371265 TI - Mechanisms of tissue damage by leukocytes. AB - Leukocyte adhesion and emigration are involved in host defense and phagocytosis and thus serve a beneficial role during the mounting of a well-contained inflammatory response. However, in certain situations, leukocytes may turn against the host and contribute to tissue damage and organ dysfunction. While trying to summarize the current opinion about the mechanisms by which leukocytes contribute to tissue damage, one finds that leukocyte-inflicted tissue damage involves a network of marked complexity, requiring an orchestrated crosstalk between different cell types, mediators, cytotoxic agents, and their respective inhibitors. Now that an abundance of information is available as to where, when, and how leukocytes contribute to tissue damage, one of the key questions remains unsolved: is leukocyte-inflicted tissue damage true damage, or is it rather a crucial step in tissue repair, healing, and scar formation? Future research will have to address this question, thoroughly differentiating between the role of leukocytes in diverse pathophysiological situations, ranging from cigarette smoke induced pulmonary emphysema and immune-triggered transplant rejection to myocardial and cerebral infarction. Knowledge of how leukocytes damage tissue only shows us the tools; knowledge of why will provide us with the basis for effective therapeutic interventions. PMID- 9371267 TI - New advances in iron metabolism, iron deficiency, and iron overload. AB - Rapid advances were made in understanding the molecular and cellular bases of iron metabolism and its disorders. Molecular mechanisms for the cellular uptake, storage, and utilization of iron were clarified in investigations of the structure and functions of transferrin, transferrin receptor, ferritin, erythroid delta-aminolevulinic acid synthase, and the RNA-binding protein termed the iron responsive-element binding protein. Evidence was obtained that a nuclear DNA binding protein, NF-E2, may be involved in the regulation of both hemoglobin synthesis in erythroid cells and of iron absorption in the intestine. Clinically, progress was made in improving the diagnosis and management of both iron deficiency and iron overload, with studies of the usefulness of serum transferrin receptor measurements, of a new therapeutic preparation of iron using a "gastric delivery system," and of the development of new orally active iron-chelating agents. PMID- 9371268 TI - Megaloblastic anemias. AB - Data continue to emerge that the low cobalamin levels often seen in the elderly and in various other settings represent a subtle cobalamin deficiency state. Even though such individuals do not have megaloblastic anemia and absorb free cobalamin normally, metabolic tests frequently document insufficiency of cobalamin that reverses after treatment with cobalamin. In many cases, malabsorption limited to food cobalamin seems responsible for the mild deficiency state. A major development related to folate has been the conclusive documentation that folate supplementation halves the risk of having a baby with neural-tube defect. The explanation for this phenomenon and the possible long term side effects of regular folate supplementation remain to be determined. Another issue with public health implications is the association of mild homocysteinemia with premature cardiovascular disease and evidence that the homocysteinemia responds to vitamin supplementation. Important advances are being made with molecular biologic techniques in unraveling the structure of key transport proteins for cobalamin and folates. PMID- 9371270 TI - Transcriptional control of erythropoiesis. AB - Over the past year, substantial progress was made toward understanding transcriptional control of red cell differentiation. Complementary DNAs encoding two novel erythroid-restricted transcription factors--globin locus control region regulatory factor NF-E2 and CACC-binding protein EKLF--were cloned and characterized. Other DNA-binding activities have been implicated in developmental regulation of hemoglobin expression; these are postulated to mediate competitive interactions between globin gene promoters. As individual transcriptional regulatory factors are better understood, attention must turn to how they interact among themselves and with other proteins to initiate and maintain the erythroid program. PMID- 9371269 TI - The molecular physiology of erythropoietin and the erythropoietin receptor. AB - Erythropoietin is the major glycoprotein hormone regulator of mammalian erythropoiesis. Erythropoietin is secreted by the kidney in response to decreased blood oxygen. It circulates in the blood, and binds and activates a specific receptor expressed on bone marrow erythroblasts. The erythropoietin receptor is a member of the cytokine receptor superfamily. Considerable details now exist to explain the biochemical events that follow erythropoietin receptor activation. Moreover, the erythropoietin receptor has been shown to play a role in the pathogenesis of various human disease including erythroleukemia and familial erythrocytosis. This review describes the structure of the cell surface erythropoietin receptor and the nature of its biochemical responses. PMID- 9371272 TI - Hemoglobin switching and its clinical implications. AB - Advances in the field of hemoglobin switching provide an excellent example of how the investigation of a biologic phenomenon may lead to the development of novel approaches for the treatment of disease. In patients with beta thalassemia and sickle cell disease, transcription switches from a normal gamma-globin gene, in the fetal stage of development, to an abnormal beta-globin gene, in the adult. Manipulations designed to achieve normal globin synthesis in patients with these disorders involve either a reversal of switching, with reestablishment of fetal hemoglobin synthesis, or the introduction of a normal exogenous globin gene to compensate for the defective endogenous gene. In this review we summarize how recent progress in understanding globin gene regulation has led to therapeutic interventions now under clinical investigation. PMID- 9371271 TI - New advances in the pathophysiology and management of sickle cell disease. AB - The formation of the sickle cell hemoglobin polymer associated with deoxygenation of the sickle erythrocyte is a complex process. There are also many intracellular, extracellular, and erythrocyte membrane changes that are recognized to play important roles in the pathophysiology of this disease. The variability among these components accounts for the diversity observed in the phenotypic expression of sickle cell disease. This article reviews some of the recent developments in the understanding of the variables involved in the pathophysiology of sickle cell disease. Some of the new developments regarding clinical complications of sickle cell disease and their management are presented. New therapeutic options are reviewed. Finally, a discussion regarding transgenic models of sickle cell disease is presented. PMID- 9371274 TI - Paroxysmal nocturnal hemoglobinuria and complement-mediated erythrocyte damage. AB - The erythrocytes of paroxysmal nocturnal hemoglobinuria are abnormally sensitive to complement-mediated lysis because they are deficient in membrane proteins that regulate the functional activity of complement. All the deficient proteins in paroxysmal nocturnal hemoglobinuria share the common structural feature of being anchored to the cell surface by a glycosyl phosphatidylinositol moiety. Recent studies showed that the first intermediate in the pathway of the glycosyl phosphatidylinositol anchor synthesis is not formed in paroxysmal nocturnal hemoglobinuria cells. This observation suggests that the molecular basis of paroxysmal nocturnal hemoglobinuria is due to an abnormality involving a gene that encodes a protein essential for the normal biosynthesis of the first intermediate. By using expression cloning, the complementary DNA (called phosphatidylinositol glycan class A [PIG-A]) that corrects the abnormality in glycosyl phosphatidylinositol-anchor synthesis in paroxysmal nocturnal hemoglobinuria cells was identified. Subsequent studies showed that the PIG-A gene is located on the X chromosome. Together, these studies provided a molecular explanation for paroxysmal nocturnal hemoglobinuria. PMID- 9371273 TI - Recent advances in immunohematology. AB - Knowledge of the biochemistry and genetics of erythrocyte blood group antigens has been growing rapidly over the past several years. Last year, the molecular basis for the major Rh blood group antigens was delineated. In addition, the genetic and biochemical bases of several other blood group antigens were identified. One of the most interesting matches of blood group antigens to a functional membrane protein was that of the Diego antigens to the erythrocyte anion channel (band 3) protein. In addition, knowledge of the molecular basis of blood group antigens is now leading rapidly to the usefulness of molecular techniques in identifying blood group genotypes and even blood group antibody specificities. This knowledge has also broadened our understanding of the pathogenesis of erythrocyte disorders associated with null blood group phenotypes. The diagnosis and treatment of autoimmune hemolytic anemia has seen slow but steady progress. New techniques appear promising as methods for distinguishing clinically important from benign autoantibodies. The molecular targets for erythrocyte autoantibodies were also largely identified. Treatment of autoimmune hemolytic anemia is also slowly being improved with the use of agents such as intravenous gammaglobulin, danazol, and immunosuppressive agents, all of which have also been important in the treatment of autoimmune thrombocytopenic purpura. PMID- 9371275 TI - Aplastic anemia and pure red cell aplasia. AB - The role of known hematopoietic growth factors in the pathogenesis of aplastic anemia and congenital hypoplastic anemia has been extensively studied and no evidence has been obtained that deficiency of these factors contributes to the hypoproliferative state in these disorders. Clonal hematopoiesis seems to be present at least in a small percentage of cases of aplastic anemia, a finding that needs further investigation. Androgens were shown to be beneficial only for women with aplastic anemia treated with antilymphocyte globulin. Unrelated-donor bone marrow transplantation is becoming a realistic approach for children and very young adults with aplastic anemia, but in older groups the survival is very poor. New observations on abnormalities of lymphokines and cytokines in Fanconi's anemia have been described, but their pathogenetic significance remains unknown. A large number of studies have excluded the possibility that abnormalities of c kit/SCF genes and their expression are responsible for the erythroid aplasia in Diamond-Blackfan syndrome. Cyclosporine was found to be an effective treatment for pure red cell aplasia associated with chronic lymphocytic leukemia. The cell membrane receptor for B19 parvovirus has been identified as the P antigen. Long term studies showed that in 20% of patients with homozygous sickle cell disease, infection by B19 does not cause erythroid aplasia. PMID- 9371276 TI - Advances in erythrocyte preservation and hemoglobin substitutes. AB - The desirability of extending the therapeutic benefits of erythrocyte transfusions beyond the currently available options is well established. Extended frozen storage of rare blood types, hemoglobin-based or artificial blood substitutes for treatment of short-term deficits in oxygen-carrying capacity, novel approaches to tissue oxygenation for cancer therapy, and efficient storage and availability of erythrocytes in military field installations are all potential applications of ongoing research and development efforts. This review explains the need for improvement in erythrocyte storage and development of blood substitutes, the current problems in the field, and the progress made toward solving these problems in the past year. PMID- 9371277 TI - Bone marrow transplantation in the treatment of thalassemia. AB - Early trials with the analysis of results in patients less than 16 years old have allowed us to identify three classes of risk using the criteria of degree of hepatomegaly, the degree of liver fibrosis, and the quality of chelation treatment given before transplant. The posttransplant disease-free survival for patients in risk classes I, II, and III and adults is today 93%, 85%, 64%, and 82%, respectively. Bone marrow transplantations, from mismatched donors and unrelated phenotypically identical donors are still experimental procedures. Bone marrow transplantation represents a desirable option of cure for severe forms of the disease when an HLA-identical donor is available. The posttransplant clinical follow-up of these patients is of particular interest in managing growth, endocrinal problems, iron overload, and normal quality and expectancy of life posttransplant. This purpose seems attainable particularly for those patients who have received transplants earlier, when histological damage of the liver and endocrine organs is not yet present. PMID- 9371278 TI - Erythrocytes. PMID- 9371279 TI - Hematopoietic growth factors. Commentary. PMID- 9371280 TI - Regulation and function of hematopoietic stem cells. AB - Hematopoietic stem cells, defined as cells with extensive self-renewal and pluripotent differentiation potential, represent a minor population of adult bone marrow (< 1 in 10(4) to 10(5) nucleated marrow cells). Recent advances in cell surface phenotype analysis and separation technology have permitted enrichment of hematopoietic stem cells. Numerous cytokines have been identified that interact additively or synergistically with hematopoietic stem cells to regulate their self-renewal and differentiation. Qualitative and quantitative analysis of hematopoietic stem cells has increasing clinical importance in areas of stem cell toxic therapy, allogeneic or autologous hematopoietic transplantation, and stem cell gene therapy for genetic or acquired diseases. PMID- 9371281 TI - Stimulation of hematopoiesis in vivo by stem cell factor. AB - The ligand for c-kit, known as stem cell factor, mast cell growth factor, or kit ligand, plays a central role in normal hematopoietic stem cell, melanocyte, and gametocyte development and function during embryogenesis and in adult life. In vitro, stem cell factor promotes the survival of hematopoietic progenitors and enhances their proliferation in response to specific growth factors. Administration of recombinant soluble stem cell factor to rodents, dogs, and baboons produces a broad array of effects on hematopoiesis, though not all lineages are equally stimulated. At doses of more than 100 micrograms/kg/d stem cell factor stimulates neutrophilia, lymphocytosis, basophilia, and reticulocytosis and increases mast cells in multiple tissues. In vivo mast cell activation can occur. Marrow cellularity is increased and progenitor cells are increased in marrow, spleen, and blood, and marrow-repopulating cells are increased in the circulation of stem cell factor-treated animals. Stem cell factor synergizes with other hematopoietic growth factors in vivo. Low-dose stem cell factor, 25 micrograms/kg/d, that does not elicit a detectable biological response, enhances the effects of granulocyte colony-stimulating factor in vivo, increasing the neutrophilia and circulation of progenitor and marrow-repopulating cells above that which is achieved with either factor alone. In phase I human trials, dose-limiting toxicities, related to mast cell activation, were reached at 25 to 50 micrograms/kg/d of recombinant human stem cell factor. At these doses, progenitor and long-term culture-initiating cells are increased in marrow and increases in circulating levels of progenitor cells of multiple types are observed. Phase I-II trials of low-dose stem cell factor in combination with granulocyte colony-stimulating factor show that the combination increases the circulation of CD34+ cells and colony-forming progenitor cells. Further studies are needed to determine the therapeutic role of stem cell factor and its effects on expansion and maintenance of hematopoietic stem cells in vivo. PMID- 9371282 TI - Advances in understanding of biological effects of interleukin-11, leukemia inhibitory factor, and macrophage inflammatory protein 1 alpha. AB - There are over 35 biologically active cytokines that have modulating effects on blood cell production at least in vitro. Among these are interleukin-11, leukemia inhibitory factor, and macrophage inflammatory protein 1 alpha, which have demonstrated effects both in vitro and in vivo. This report reviews the recent studies describing the production and action of these three cytokines, which may in the future be useful in treating patients with blood disorders. PMID- 9371283 TI - Hematopoietic effects and clinical uses of granulocyte-macrophage colony stimulating factor and PIXY321. AB - The clinical uses of granulocyte-macrophage colony-stimulating factor (GM-CSF) are expanding. GM-CSF was originally approved for use after autologous bone marrow transplantation. More recent phase III studies using GM-CSF after allogenic marrow transplantation show a similar reduction in the duration of neutropenia and monocytopenia. In phase III trials following standard-dose chemotherapy, GM-CSF significantly reduced treatment-related neutropenia and morbidity and, in one study, mortality. Nonrandomized studies using GM-CSF prior to and during chemotherapy for acute myeloid leukemia to improve remission rates have not demonstrated an obviously significant benefit. Other studies of GM-CSF to augment cancer therapies directly and to aid in the treatment of infection are in progress. PIXY321 is a fusion protein of GM-CSF and interleukin-3. PIXY321 was developed, in part, because in vitro and in vivo laboratory studies suggested synergy between its two components. Phase I-II clinical studies using PIXY321 are preliminary but show encouraging results with stimulation of multilineage hematopoiesis. PMID- 9371284 TI - Hematologic effects of interleukin-1 and interleukin-6. AB - Interleukin-1 and interleukin-6 are two of a great number of cytokines involved in the synergistic regulation of hematopoietic progenitor cell growth. Clinical descriptions that suggest several therapeutic uses for interleukin-1 and interleukin-6 have appeared. In either high-dose chemotherapy or bone marrow transplantation, either cytokine can be myeloprotective or myelorestorative and can increase platelet recovery. Also, both cytokines could be useful in stimulating the peripheralization of stem-progenitor cells in vivo. In vitro, both cytokines have proven useful in the ex vivo expansion of hematopoietic progenitor cells and subsequent reinfusion in patients undergoing autologous bone marrow transplantation. Mechanistically, both stimulate production of other regulators of hematopoiesis, induce increased cell surface expression of receptors for hematopoietic growth factors, and shorten the cell cycle transit time of progenitors. Differences in the actions of interleukin-6 and interleukin 1 on highly enriched and purified stem cells are starting to emerge, with proliferation in stem cell factor and interleukin-6 preserving marrow repopulating ability of stem cells, and the proliferative stimulus of stem cell factor and interleukin-1 leading to more rapid differentiation. PMID- 9371285 TI - Effects of granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor on neutrophil formation and function. AB - Work published in the past year has significantly increased our understanding of the intracellular signaling pathways that are activated following granulocyte macrophage colony-stimulating factor or granulocyte colony-stimulating factor binding to cell surface receptors. The involvement of nonreceptor protein tyrosine kinases, in particular the JAK2 kinase, appears to be a major signal transduction pathway involved in the response to several hemopoietic cytokines. Further data continue to accrue on the clinical role of granulocyte colony stimulating factor, in particular in the treatment of chronic neutropenia. Increased clinical experience with colony-stimulating factors has revealed side effects that may occur with chronic use. The effects of colony-stimulating factors on neutrophil function are shown increasingly to be complex and to involve significant interactions with other proinflammatory cytokines. PMID- 9371286 TI - Advances in the clinical use of granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor to intensify cancer chemotherapy. AB - The majority of human malignancies remain refractory to current therapeutic regimens. Several animal and human models provide evidence of a dose-response effect of many chemotherapeutic agents in a variety of malignancies. In recent years dose escalation with bone marrow transplant support has provided encouraging evidence that increased doses of antineoplastic agents may overcome clinical drug resistance. However, this approach has been limited by hematologic toxicity. This problem has been abrogated by the development and use of hematopoietic growth factors. These agents now offer the oncologist new treatment opportunities. PMID- 9371287 TI - Measurement and clinical significance of circulating hematopoietic growth factor levels. AB - Immunoassays have recently made it possible to specifically measure the circulating levels of hematopoietic growth factors. This is helping us to understand the in vivo regulation of hematopoiesis under conditions of steady state or stress, providing insights into the physiological roles of hematopoietic growth factors and their importance in the pathogenesis of disease. As mediators of pathological processes, hematopoietic growth factors may be targets for antagonist therapy in some diseases. Exogenous hematopoietic growth factors may also be useful therapeutically to augment physiological responses, so understanding hematopoietic growth factor regulation and serum levels may assist the development of specific therapies. Hematopoietic growth factor levels may also serve as tumor markers and assist prognostication or monitoring during the clinical course of an illness. The growth factors of particular interest include the four classic colony-stimulating factors: granulocyte-macrophage colony stimulating factor, granulocyte colony-stimulating factor, macrophage colony stimulating factor, and multi-colony-stimulating factor, also known as interleukin-3. Other cytokines with hematopoietic growth factor activity include interleukin-1, interleukin-6, interleukin-11, stem cell factor (also known as Steel factor or mast cell growth factor), and leukemia inhibitory factor. PMID- 9371288 TI - Hematopoietic growth factors. PMID- 9371289 TI - Specific genetic defects as targets for selective therapies. Commentary. PMID- 9371290 TI - Acute leukemia. AB - Within the past year substantial progress has been made in understanding the molecular changes underlying the development of acute leukemia. Development of molecular probes allowed substantial improvements in the detection of minimal residual disease. Pilot studies underlined the correlation between the expression of the multidrug resistance gene and the likelihood of response to chemotherapy. The expression of mdr-1 apparently correlates with the expression of certain surface antigens like CD34 and CD7, which by themselves are associated with the expression of bcl-2 and poor treatment response. The value of hematopoietic growth factors to overcome drug resistance has not yet been clearly demonstrated in clinical trials, but they seem to reduce early mortality in elderly patients with acute myeloid leukemia when given after chemotherapy. Substantial progress has been made in the understanding of molecular changes in acute promyelocytic leukemia. Combination of all-trans retinoic acid and chemotherapy is the treatment of choice in acute promyelocytic leukemia. Allogeneic bone marrow transplantation proved to be superior in certain high-risk groups of patients with acute leukemia, including those with acute lymphoblastic leukemia with the bcr-abl configuration. The value of allogeneic bone marrow transplantation from related and unrelated donors, as well as the value of autologous bone marrow transplantation, is increasingly defined in randomized trials. PMID- 9371291 TI - Secondary myelodysplastic syndromes and leukemias. AB - Although therapy-related (secondary) myelodysplastic syndromes and acute nonlymphocytic leukemias are most frequently observed following therapy of Hodgkin's disease and non-Hodgkin's lymphoma, the therapy of acute lymphocytic leukemia, multiple myeloma, polycythemia vera, cancers of breast, lung, ovary, gastrointestinal tract, testis, and soft tissues is also associated with subsequent development of leukemia. A preceding myelodysplastic syndrome is observed in over 70% of patients who develop therapy-related leukemia, in contrast to patients with de novo leukemia in whom approximately 20% of patients have similar prodromal syndromes. Chemotherapeutic drugs--including alkylating agents, platinum analogs, and epipodophyllotoxins--and ionizing radiation have both been implicated in the etiology of secondary tumors. The median duration from time of chemotherapy or radiation therapy, or both, to diagnosis of secondary leukemia is 3 to 4 years. The risk for development of secondary leukemia is highest between 24 and 72 months following cytotoxic therapy, with a steady decline in incidence thereafter. Of those people who will develop secondary leukemia, approximately 6% of patients do so within the 1st year, whereas 15% of patients will not do so until more than 7 years from commencement of mutagenic therapy. We review here selected recent publications on clinical and therapeutic data in therapy-induced myelodysplasia and acute leukemia. PMID- 9371292 TI - Recent advances in biological and therapeutic aspects of myeloproliferative disorders. AB - Chronic myeloproliferative disorders are clonal neoplasias that originate from a clonal pluripotent stem cell and may have a more or less pronounced tendency to acute progression. Except for chronic myelogenous leukemia marked by the Ph chromosome, the BCR/ABL rearrangement, or both, the other chronic myeloproliferative disorder subtypes show less specific, although recurrent, karyotypic and molecular abnormalities. We report here more recent advances in cytogenetics, molecular biology, and treatment of the most common chronic myeloproliferative disorders. PMID- 9371293 TI - Chronic lymphocytic leukemia and hairy-cell leukemia. AB - In recent years, major advances in our understanding of the biology of the chronic lymphoid leukemias have been accompanied by the emergence of new therapeutic options. Chronic lymphocytic leukemia, the most common of these disorders, appears to be related to a failure of apoptosis, leading to accumulation of functionally abnormal lymphocytes. Fludarabine, a nucleoside analogue that may activate apoptosis, has emerged as the most effective agent for newly diagnosed as well as relapsed patients with chronic lymphocytic leukemia. Nevertheless, few if any patients are cured with this agent. Unique chemotherapeutic and biologic therapies are being explored, and new strategies combining several approaches will likely be established. For patients with hairy cell leukemia, pentostatin and 2-chlorodeoxyadenosine achieve durable complete remissions in 65% to 85% of patients, with comparable toxicity. PMID- 9371294 TI - Multiple myeloma and other differentiated B-cell disorders. AB - Molecular genetic techniques that are used to define the myeloma precursor cell and find its origin are generating new insights into the biology of this generally incurable malignancy. In the absence of curative therapy, new techniques to distinguish between myeloma and more benign plasma cell disorders are particularly valuable. The increasing application of myeloablative therapy as early consolidation therapy is improving survival in myeloma. Interferon alpha maintenance therapy prolongs plateau phase in patients responding to conventional induction therapy and prolongs both remission duration and survival in patients who have received myeloablative consolidation therapy. Patients who show early resistance to induction chemotherapy may particularly benefit from myeloablative therapy. The role of allogeneic bone marrow transplantation in myeloma therapy remains undefined. Attempts to modulate cytotoxic drug resistance seem likely to be clinically successful in the near future. Insights into the roles of cytokines such as interleukin-1 and interleukin-6 will lead to new therapies. Clonal plasma cell expansion results in the plasma cell disorders including overt malignancy, multiple myeloma, plasma cell leukemia, solitary plasmacytoma of bone, or more indolent disorders including monoclonal gammopathy of undetermined significance. Selected important data on the biology and therapy of these disorders are highlighted. PMID- 9371295 TI - Recent advances in Hodgkin's disease. AB - Despite the undoubted advances in the therapy of Hodgkin's disease in the past 30 years, there remain a large number of controversial and unresolved issues surrounding the pathogenesis and the treatment of this condition. The aim of this article is to review the current literature in the context of these controversies and to highlight studies that have used modern technologies to give an insight into the pathogenesis of Hodgkin's disease. PMID- 9371296 TI - Non-Hodgkin's lymphoma. AB - The increasing incidence of lymphomas is related to environmental factors including occupational exposures and HIV infection. Molecular and immunologic studies have recently defined some new clinico-pathologic entities such as mantle cell lymphoma and lymphoma of mucosal-associated lymphatic tissue. However, the most prevalent lymphomas are follicular lymphomas and diffuse aggressive histology lymphomas. Follicular lymphomas are curable with radiation therapy when they are localized to lymph nodes. Efforts to improve treatment results in patients with advanced follicular lymphoma are focusing primarily on the use of additional therapy (eg, interferon, high-dose chemoradiotherapy, and immunologic therapy) after induction of a complete response by combination chemotherapy. Aggressive-histology lymphoma is curable in more than 85% of patients when it is localized and in more than 50% of patients when it is disseminated. Efforts to improve treatment results are focusing primarily on delivering therapy with higher-dose intensity. PMID- 9371297 TI - Clinical applications of the hematopoietic growth factors. AB - Hematopoiesis occurs in a microenvironment containing a variety of growth factors. Normal hematopoietic cells require these growth factors for viability, proliferation, and differentiation. The purification and molecular cloning of human growth factors has permitted a detailed analysis of hematopoiesis. Furthermore, the commercial production of growth factors resulted in their widespread introduction into clinical practice to limit chemotherapy-induced neutropenia. Recently, clinical trials of growth factors have expanded to test their direct anticancer effects, to improve the efficacy of chemotherapy by stimulating cell division, and to use them as biological modulators to inhibit tumor growth. This review focuses on a few clinical uses of recombinant growth factors. PMID- 9371298 TI - Hematopoietic cell proliferation and differentiation. AB - Most hematopoietic stem cells are quiescent in the G0 stage of the cell cycle. Certain combinations of hematopoietic growth factors can bind to their cognate receptors on the stem cell surface, shorten the G0 stage of the cell cycle, and stimulate cell division. Hematopoietic growth factors also act on committed progenitors to increase their survival and to amplify maturing populations by stimulating proliferation. Although differentiation is probably determined largely by an intrinsic program, there is evidence that certain receptors expressed on more mature cells can also direct differentiation. This view is still controversial, as is the view that hematopoietic growth factors act merely to prevent apoptosis. Different members of the hematopoietic growth factor family of receptors recruit overlapping sets of tyrosine kinases and share common signal transduction pathways such as Ras. They also directly activate a cytoplasmic class of transcription factors that then translocate to the nucleus. The development of committed hematopoietic progenitor cells into mature effector cells is regulated by "master" transcription factors that recognize motifs in the promoters of many genes that encode lineage-specific proteins. PMID- 9371299 TI - Epidemiology of human leukemia. AB - The leukemias show clear geographic, racial, ethnic, age, and gender variation in both incidence and mortality, and the patterns of occurrence differ among subtypes. Despite decades of epidemiologic study, the known and suspected risk factors for leukemia are insufficient to explain more than a small fraction of the observed variation in the occurrence of the leukemias. Important contributions to the literature in 1993 included studies further clarifying the role of known risk factors (ionizing radiation, certain chemotherapeutic agents, and specific occupational chemical exposures) and suspected risk factors (infectious agents, electromagnetic fields, cigarette smoking, other chemotherapeutic agents, and additional occupational chemical exposures) in leukemogenesis. PMID- 9371300 TI - Hematologic malignancies. PMID- 9371301 TI - Treatment of venous thromboembolism. AB - There have been some important advances in the treatment of venous thromboembolism during the past 18 months. A randomized trial has confirmed earlier observations indicating an adequate initial heparin effect is required to prevent recurrent venous thromboembolism, and it is critical to achieve this effect within the first 24 hours of therapy. The need to use a validated protocol for administering intravenous heparin is now firmly established. The clinician has a choice between two protocols that have been validated by randomized trials and provide both effective and safe heparin therapy. For patients with clinically suspected pulmonary embolism, the clinician now has a practical noninvasive strategy that avoids pulmonary angiography, identifies patients with proximal vein thrombosis who require treatment, and avoids the need for treatment and further investigation in the majority of patients. PMID- 9371303 TI - New markers for in vivo coagulation. AB - Advances in our understanding of the biochemistry of the hemostatic mechanism have led to the development of sensitive methods for measuring peptides, enzyme inhibitor complexes, or enzymes that are liberated with the activation of the coagulation system in vivo. Studies employing these markers indicate that a biochemical imbalance between procoagulant and anticoagulant mechanisms can be detected in the blood of humans prior to the appearance of thrombotic phenomena. Properly designed prospective studies will be required to determine whether these assay techniques will enable us to identify individuals who are entering a clinically relevant hypercoagulable state and intervene with appropriate therapy prior to the onset of overt thrombotic disease. PMID- 9371302 TI - Treatment of arterial thromboembolic disease. AB - Prevention of thrombus formation and embolization remains a therapeutic challenge. Recent advances in the treatment of arterial thromboembolic disease include prevention of thromboembolism in patients with nonrheumatic atrial fibrillation with warfarin or aspirin, and combined therapy with low-dose aspirin, and anticoagulants for prosthetic heart valves and coronary artery disease. The potential of direct thrombin inhibition for treatment of acute coronary syndromes is also discussed. PMID- 9371304 TI - Advances and dilemmas in factor XI. AB - Factor XI is a key component of the intrinsic pathway of blood coagulation in vitro. The poor correlation between the clinical bleeding diathesis in factor XI deficiency and abnormalities in clotting assays that measure intrinsic coagulation brings into question the role of this serine protease in in vivo hemostasis. The characterizations of the point mutations responsible for the majority of cases of severe factor XI deficiency in Ashkenazi Jews and subsequent epidemiologic studies have provided insight into the perplexing hemostatic abnormalities in this disorder. It appears that excessive bleeding in factor XI deficiency depends on the severity of the deficiency in certain situations and on the location of the hemostatic challenge in others. Additional coexisting abnormalities of hemostasis, such as von Willebrand's disease, may also be responsible for variation in clinical presentation, particularly in those individuals with mild factor XI deficiency. The absence of abnormal bleeding in congenital deficiency of factor XII, the protease that activates factor XI in the intrinsic cascade, has stimulated a search for other mechanisms for factor XI activation. Recent studies have pointed to the serine protease thrombin and autoactivation by activated factor XI as possible alternatives to factor XII as activators of factor XI. These findings suggest that factor XI, rather than operating in a pathway for the initiation of hemostasis, may function in the consolidation of clot formation after the initiation of the hemostatic process by other mechanisms. PMID- 9371305 TI - Antiphospholipid antibodies and thrombosis. AB - Antiphospholipid antibodies (eg, anticardiolipin antibodies or the lupus anticoagulant) are a fascinating set of autoantibodies that have been linked to venous and arterial thrombosis, immune-mediated thrombocytopenia, and recurrent pregnancy loss. This review high-lights recent advances in the immunology of antiphospholipid antibodies and their target antigens, potential mechanisms of thrombosis and thrombocytopenia, and new methods for laboratory identification of these antibodies. Clinical syndromes associated with antiphospholipid antibodies are also covered, including ischemic neurological disorders, cardiac lesions, venous thromboembolism, and pregnancy loss. In each instance, recommendations for therapy are discussed. PMID- 9371306 TI - von Willebrand's factor and von Willebrand's disease. AB - von Willebrand's factor is required for platelet adhesion to subendothelium, and for normal factor VIII survival in the circulation. These functions require the assembly of von Willebrand's factor into multimers that exhibit properly regulated binding to platelet glycoprotein lb. Recent studies suggest that the propeptide of von Willebrand's factor may catalyze multimer assembly and have identified new segments of von Willebrand's factor that appear to regulate its affinity for glycoprotein lb. Two segments of von Willebrand's factor have been found to interact with collagen type VI, which is a candidate binding site for von Willebrand's factor in the subendothelium. Advances in the identification of mutations have prompted a reclassification of von Willebrand's disease. ABO antigens on von Willebrand's factor may impair the efficacy of plasma or recombinant von Willebrand's factor when administered to patients with incompatible ABO blood type. PMID- 9371307 TI - Thrombocytopenia in HIV infection. AB - Thrombocytopenia commonly occurs in individuals with HIV disease. However, profound thrombocytopenia, occurring in only 1.5% of cases, is relatively rare. The mechanisms of thrombocytopenia appear to be multifactorial: profound thrombocytopenia in HIV disease is related to an immune destruction either by antiplatelet antibodies or by immune complexes. In addition, a defect in platelet production is quite frequent both in immune thrombocytopenia (ITP) and in mild thrombocytopenia. This impaired platelet production may be due to an HIV infection of megakaryocytes that express a functional CD4 molecule. Treatment of HIV-associated thrombocytopenia is quite similar to that of non-HIV ITP. However, zidovudine increases the platelet count without correlation with its antiviral effect. In animal models and HIV patients, this enhancement of platelet count appears to be due to a stimulation of platelet production, the precise mechanism of which remains unknown. Splenectomy is as effective in severe HIV thrombocytopenia as in non-HIV ITP and has no significant adverse effects on HIV disease. PMID- 9371308 TI - Platelets and cytokines. AB - Cytokines that are capable of stimulating megakaryocytopoiesis provide new approaches to ameliorate clinical thrombocytopenia. Administration of non-lineage specific factors that promote megakaryocytic progenitor cell proliferation has been shown to increase platelet counts following chemotherapy. Preclinical and preliminary clinical studies have shown that cytokines that enhance maturation of megakaryocytes also accelerate platelet recovery. Combinations of factors may prove even more efficacious and novel approaches to enhance platelet recovery using mobilized peripheral blood stem cells have been introduced. Lineage specific cytokines may appear in the near future. The notion that platelet function might be enhanced with cytokines has been proposed; whether this will translate into clinical utility is not clear. Despite this recent progress in the development of thrombopoietic cytokine therapy, an important but unresolved matter is the establishment of precise clinical indications for such treatment. PMID- 9371309 TI - Human platelet alloantigens. AB - The past 20 years have witnessed a revolution in our understanding of platelet alloimmunity, both in terms of basic findings and clinical applications. This review highlights recent molecular biological studies that have impacted our understanding of the structural basis for the formation of human platelet alloantigenic epitopes, and shows how these findings have improved methods for their detection and genotypic analysis. Finally, implications for dissecting the way in which the immune system both recognizes and responds to platelet alloantigens are discussed. PMID- 9371310 TI - Molecular abnormalities in Glanzmann's thrombasthenia, Bernard-Soulier syndrome, and platelet-type von Willebrand's disease. AB - Genetic defects of the blood platelet membrane glycoproteins, GPIIb-IIIa (alpha IIb/beta 3; CD41/CD61) and GPIb-V-IX (CD42) are the origin of several rare bleeding disorders, the best known of which are Glanzmann's thrombasthenia, Bernard-Soulier syndrome, and platelet-type von Willebrand's disease. In Glanzmann's thrombasthenia, GPIIb-IIIa are missing or defective and platelet aggregation is lacking or reduced. Either gene can be affected and mutations leading to lack of expression or to expression of poorly functional forms have been described. In Bernard-Soulier syndrome, GPIb-V-IX are missing or defective, leading to poor platelet adhesion at high-shear stress to damaged vessel wall and reduced platelet response to thrombin. Mutations in both GPIb alpha (CD42b) and GPIX (CD42a) have been described. Mutations in GPIb alpha can also lead to platelet-type von Willebrand's disease in which GPIb-V-IX are expressed normally but bind von Willebrand's factor spontaneously, which leads to platelet aggregation and thrombocytopenia. PMID- 9371311 TI - Hemostasis and thrombosis. PMID- 9371312 TI - Transplantation biology. AB - A variety of hemopoietic tissues are now being used as a source of stem cells for clinical transplantation. These tissues all have different biological properties, which are not yet fully understood, as well as particular clinical applications, advantages, and disadvantages. The development of protocols for the manipulation of stem cells prior to infusion into patients will, it is hoped, lead to the further improvement of stem cell replacement therapy including the use of stem cells as vectors for expressing transduced genes. Success in these efforts will depend on an improved understanding of the biological principles underlying hemopoietic stem cell transplantation. PMID- 9371313 TI - Allogeneic bone marrow transplantation for leukemia. AB - Allogeneic bone marrow transplantation cures some persons with acute lymphoblastic leukemia, acute myeloblastic leukemia, and chronic myelogenous leukemia. Considerable data suggest that most cures result from immune-mediated antileukemia effects of the transplant rather than intensive pretransplantation chemotherapy and radiation. The mechanism of these immune-mediated effects, termed graft-versus-leukemia, is unknown. In the past 25 years more than 20,000 allogeneic transplantations were performed worldwide in persons with leukemia. Here we review single- and multicenter studies and analyses of the International Bone Marrow Transplant Registry on results of allografts for leukemia. PMID- 9371314 TI - Complications of allogeneic bone marrow transplantation. AB - Recent research has increased our understanding of the pathogenesis and prevention of the immediate and delayed complications of allogeneic bone marrow transplantation. Cytokines appear to play a major role in the pathogenesis of acute graft-versus-host disease and new therapies are being developed to modulate these effects. Risk factors for fatal venoocclusive disease of the liver such as elevated serum transaminase levels and fever prior to transplantation can be used in mathematical models to predict the outcome of venoocclusive disease. Use of total-body irradiation in pretransplantation conditioning regimens increases the risk of secondary cancers and is being used less commonly in patients with nonmalignant hematologic conditions. For patients with malignant diseases, fractionation of total-body irradiation have been shown to delay the onset and reduce the severity of radiation-induced cataracts. These and other late effects such as the development of chronic graft-versus-host disease and associated infections are major determinants of the quality of life following allogeneic marrow transplantation. Increased understanding of these complications assists the hematologist in long-term follow-up care of the marrow graft recipient. PMID- 9371315 TI - Autologous bone marrow transplantation. AB - High-dose chemotherapy with autologous stem cell support is increasingly used in malignant disease. There are few data from randomized, controlled, clinical studies on which to base our approach, and many publications consist of retrospective analyses that do not help elucidate the overall role of high-dose therapy. There has been a rapid increase in the use of peripheral blood as a source of stem cells that may reduce the toxicity of the procedure, but this has spawned an enthusiasm for high-dose therapy particularly in conditions such as myeloma and solid tumors where, as yet, there are few clinical data to demonstrate survival benefit. PMID- 9371316 TI - Cytomegalovirus infection. AB - Cytomegalovirus infection was for many years one of the major complications of allogeneic bone marrow transplantation. During the past few years there have been major advances in the management of patients at risk for cytomegalovirus disease, and there are now several strategies that can be used. Antiviral prophylaxis has improved considerably and there are now three antiviral agents that can be used. Immunoprophylaxis by infusion of specific cytotoxic T cells is now feasible. The development of techniques for rapid diagnosis of cytomegalovirus infection including the antigenemia assay and the polymerase chain reaction for detection of cytomegalovirus DNA have made the use of preemptive therapy an attractive strategy. The outcome of therapy of cytomegalovirus pneumonia is still poor, with a survival of only approximately 50%, despite use of the combination of ganciclovir and high-dose immunoglobulin. PMID- 9371317 TI - Gene transfer into the hematopoietic system. AB - Efficient transfer of heterologous genes into long-term reconstituting stem cells remains difficult to achieve in large animal models and humans. Long-term expression of introduced gene sequences in hematopoietic cells after gene transfer and bone marrow transplantation procedures is usually seen in less than 5% of cells. Retroviral vectors remain the standard tool for this technology, but these vectors have distinct disadvantages, such as the requirement for cycling target cells, random integration into the infected cell genome, and problems with long-term gene expression in long-term reconstituting stem cells. Novel retroviral vectors and producer cell lines that may address some of these problems have been constructed. In addition, modifications of the retroviral infection protocol and the use of alternative stem cell sources such as cord blood or mobilized peripheral blood cells have been tested with some promise. Recent data suggest that adeno-associated virus-based vector might prove an alternative to retroviral vectors in some cases. PMID- 9371318 TI - Immunogenetics. AB - Interest in the complexity of the HLA system and its relevance in the selection of unrelated bone marrow donors has had an important impact on our understanding of the immunogenetics of HLA and non-HLA or minor histocompatibility systems. More than 50 genes on the short arm of chromosome 6, which carries the information for HLA, have been identified and there are more to come. HLA-class I and HLA-class II each have more than 200 alleles, and the number is growing. The HLA-C antigens appear to act as targets for natural killer cells. New inroads have been made in the recognition of the minor histocompatibility antigens HA-1 to -5, which can be recognized by cytotoxic T-cell clones and are inherited in a Mendelian fashion. A mismatch for HA-1 might lead to graft-versus-host disease. The introduction of new technologies, especially polymerase chain reaction, has been immensely helpful in mapping the genetic complexity of HLA. Methodology now allows typing for HLA on the level of DNA in a matter of a few hours and is most useful when selecting a suitable bone marrow donor. The new genetic information available makes it clear that many so-called HLA matched unrelated bone marrow transplants performed in the past were actually mismatched. Nevertheless, many of them had a good clinical outcome. It is clear that one of the most important challenges is to determine which mismatched transplants will fare well and which should be avoided. Recent findings in organ transplantation might be helpful here. PMID- 9371319 TI - Transfusion medicine. PMID- 9371320 TI - Transfusion and HIV. AB - Over a decade has passed since the first cases of AIDS were reported in hemophiliacs and transfusion recipients. Studies published over the past year offer an increasingly clear understanding of the extent of the early transfusion associated AIDS epidemic, and of the effectiveness of progressive donor screening measures in safeguarding the blood supply from HIV. Although a number of recent studies have confirmed that the residual risk of HIV infection from blood and blood components is very small, effort continues toward development of new screening tests and viral inactivation procedures. Deciding whether these procedures warrant implementation will be a major challenge in the upcoming years. PMID- 9371321 TI - Leukocyte depletion of cellular blood components. AB - Clinical studies have indicated that the use of leukocyte-reduced cellular blood components produced in the laboratory may prevent febrile reactions and delay or prevent alloimmunization to HLA antigens and refractoriness to platelet transfusion. Additional investigations regarding the effects of the use of leukocyte-reduced blood components were reported during the past year. A recent study in patients with hematologic malignancy that employed the commonly used bedside leukocyte-reduction filters failed to confirm a decrease in the rate of alloimmunization, except in a subgroup of patients with acute myelogenous leukemia. Another major multicenter trial confirmed the effectiveness of leukocyte-reduced blood components in the prevention of cytomegalovirus infection. The effect of allogeneic leukocytes in transfused blood on immune function in patients undergoing colorectal surgery continues to receive attention. Whereas one study failed to demonstrate an adverse effect of standard blood components on disease recurrence or survival, a second study demonstrated a marginally significant decrease in infectious complications in patients who received only leukocyte-reduced blood. Increasingly efficient leukocyte-reduction filters have been developed for cellular blood components, many of which are best suited for laboratory filtration of unstored blood. Laboratory studies indicate that prestorage leukocyte-reduction of cellular blood components does not impair erythrocyte or platelet function and will not increase the incidence of microbial contamination of blood. New methods that employ flow cytometry should enable improved quality control of blood components rendered leukocyte-reduced by the newer, more efficient filters. Finally, a cost-benefit analysis suggests that the appropriate use of leukocyte-reduction filters for acute leukemia patients may reduce the cost of health care to these patients. PMID- 9371322 TI - Cytokines and erythrocyte incompatibility. AB - The strong resemblance between the clinical manifestations of hemolytic transfusion reactions and sepsis, in which cytokine production has a central role, suggests that similar pathophysiologic mechanisms are involved. There is an expanding body of clinical and experimental evidence that cytokines, especially interleukin-1, tumor necrosis factor, interleukin-6, and interleukin-8, are principle mediators of immune responses to erythrocyte incompatibility. Recent studies have further suggested that the monocyte chemotactic and activating factor, monocyte chemoattractant protein-1, and the anti-inflammatory cytokine interleukin-1 receptor antagonist are produced in experimental models of hemolytic transfusion reactions. Differing levels and patterns of expression of these cytokines may be seen in models of intravascular hemolysis due to ABO incompatibility and extravascular hemolysis due to Rh incompatibility, which correlate with the recognized clinical differences between these two types of reactions. Furthermore, recent studies have demonstrated that several of these same cytokines are produced during the storage of platelet concentrates, which may account for some febrile reactions that are not prevented by the use of leukocyte reduction filters. PMID- 9371323 TI - Mechanisms of transfusion-associated immunosuppression. AB - Many studies have reported allogeneic blood transfusions to be associated with adverse effects in recipients. These include a variety of transfusion reactions, graft-versus-host disease, alloimmunization, the transmission of infectious agents, and immunomodulation. In some instances the immunomodulatory effect has been reported to be beneficial to the recipient, i.e., recipients of renal allografts, individuals with Crohn's disease, and women with recurrent spontaneous abortions. Recent evidence indicates, however, that this autologous blood transfusion-associated immunomodulation might adversely affect the prognosis in patients with a malignancy as well as increase their risk for postoperative bacterial infection. The mechanisms of the autologous blood transfusion-associated immunosuppressive effect remain ill defined, although recent evidence indicates that such effects are probably due to the infusion of allogeneic donor leukocytes, or their products, present in the cellular blood products used for the transfusion. Recent experimental animal data indicate that this autologous blood transfusion-associated immunomodulatory effect can be ameliorated by the prestorage leukodepletion of allogeneic blood. Although data from animal experiments are useful in defining various in vivo biologic activities, properly designed prospective clinical trials are required to provide definitive indications as to whether patients with a malignancy undergoing curative surgery should receive leukodepleted allogeneic cellular blood products and the appropriate timing for such leuko-depletion. PMID- 9371325 TI - Bone marrow transplantation. PMID- 9371324 TI - Role of hematopoietic growth factors in transfusion medicine. AB - Recombinant human growth factors are expected to have a significant impact on the use of allogeneic blood components. For example, recombinant human erythropoietin has had a significant impact on blood transfusion in renal dialysis patients. Likewise, myeloid growth factors have reduced infections and hospital stay by promoting hematologic recovery after high-dose ablative chemotherapy. The high costs of these agents mandate that their use be limited to settings where they are clinically indicated. This review discusses the emerging clinical data to help establish guidelines for the use of hematopoietic growth factors. Comments regarding the myeloid growth factors are restricted to their emerging role in stem cell transplantation, because this clinical setting is anticipated to have the greatest impact in the use of allogeneic blood components in oncology. PMID- 9371326 TI - Transfusion medicine. PMID- 9371327 TI - Why are antibiotic resistance genes so resistant to elimination? PMID- 9371328 TI - In vitro preclinical evaluation studies with the echinocandin antifungal MK-0991 (L-743,872). AB - The echinocandin MK-0991, formerly L-743,872, is a water-soluble lipopeptide that has been demonstrated in preclinical studies to have potent activity against Candida spp., Aspergillus fumigatus, and Pneumocystis carinii. An extensive in vitro biological evaluation of MK-0991 was performed to better define the potential activities of this novel compound. Susceptibility testing with MK-0991 against approximately 200 clinical isolates of Candida, Cryptococcus neoformans, and Aspergillus isolates was conducted to determine MICs and minimum fungicidal concentrations MF(s). The MFC at which 90% of isolates are inhibited for 40 C. albicans clinical isolates was 0.5 microg/ml. Susceptibility testing with panels of antifungal agent-resistant species of Candida and C. neoformans isolates indicated that the MK-0991 MFCs for these isolates are comparable to those obtained for susceptible isolates. Growth kinetic studies of MK-0991 against Candida albicans and Candida tropicalis isolates showed that the compound exhibited fungicidal activity (i.e., a 99% reduction in viability) within 3 to 7 h at concentrations ranging from 0.06 to 1 microg/ml (0.25 to 4 times the MIC). Drug combination studies with MK-0991 plus amphotericin B found that this combination was not antagonistic against C. albicans, C. neoformans, or A. fumigatus in vitro. Studies with 0 to 50% pooled human or mouse serum established that fungal susceptibility to MK-0991 was not significantly influenced by the presence of human or mouse serum. Results from resistance induction studies suggested that the susceptibility of C. albicans was not altered by repeated exposure (40 passages) to MK-0991. Erythrocyte hemolysis studies with MK-0991 with washed and unwashed human or mouse erythrocytes indicated minimal hemolytic potential with this compound. These favorable results of preclinical studies support further studies with MK-0991 with humans. PMID- 9371329 TI - Evaluation of the echinocandin antifungal MK-0991 (L-743,872): efficacies in mouse models of disseminated aspergillosis, candidiasis, and cryptococcosis. AB - The in vivo activity of the Merck antifungal echinocandin drug candidate MK-0991 (L-743,872) was evaluated in mouse models of disseminated candidiasis, aspergillosis, and cryptococcosis. The echinocandins are potent inhibitors of 1,3 beta-D-glucan synthase. Two models of disseminated candidiasis were used. In a Candida albicans mouse survival model with both DBA/2N and CD-1 mice, estimates of the 50% effective doses (ED50s) of MK-0991 were 0.04 and 0.10 mg/kg of body weight/dose at 21 days after challenge, respectively. In a C. albicans target organ assay (TOA) with DBA/2N mice, MK-0991 at levels of > or =0.09 mg/kg/dose significantly reduced the numbers of C. albicans CFU/g of kidneys compared to the numbers in the kidneys of control mice from 1 to 28 days after challenge. Even when given as a single intraperitoneal dose either 30 min or 24 h after challenge, MK-0991 was effective and significantly reduced the numbers of C. albicans CFU/g of kidney compared to those in the controls. MK-0991 was >300-fold less active when it was administered orally than when it was administered parenterally. MK-0991 was efficacious in mouse TOAs against other C. albicans strains and Candida species including Candida tropicalis, Candida (Torulopsis) glabrata, Candida lusitaniae, Candida parapsilosis, and Candida krusei. MK-0991 was ineffective against disseminated Cryptococcus neoformans infections. In the model of disseminated aspergillosis in mice, MK-0991 at doses of > or =0.02 mg/kg/dose significantly prolonged the survival of DBA/2N mice, with estimates of the ED50 and ED90 of MK-0991 being 0.03 and 0.12 mg/kg/dose, respectively, at 28 days after challenge. MK-0991 is a potent, parenterally administered therapeutic agent against disseminated candidiasis and aspergillosis that warrants further investigation in human clinical trials. PMID- 9371330 TI - Preliminary animal pharmacokinetics of the parenteral antifungal agent MK-0991 (L 743,872). AB - MK-0991 (L-743,872) is a potent antifungal agent featuring long half-life pharmacokinetics. The pharmacokinetics of MK-0991 administered intravenously to mice, rats, rhesus monkeys, and chimpanzees is presented. Unique to MK-0991 is its consistent cross-species performance. The range of values for the pharmacokinetic parameters were as follows: clearance, 0.26 to 0.51 ml/min/kg; half-life, 5.2 to 7.6 h; and distributive volume, 0.11 to 0.27 liters/kg. The level of protein binding of MK-0991 was determined to be 96% in mouse and human serum. The compound exhibited high affinities for human serum albumin and at least two lipid components. The rationale for the selection of MK-0991 as a drug development candidate was based on its two- to threefold superior pharmacokinetic performance in chimpanzees over the performance of an otherwise equivalent analog, L-733,560. Once-daily dosing for MK-0991 is indicated by a graphical comparison of levels in the circulations of chimpanzees and mice. In a study of the pharmacokinetics of MK-0991 in mouse tissue, the organs were assayed following intraperitoneal administration. The area under the concentration-versus time curves (AUC) segregated the tissues into three exposure categories relative to plasma. The tissues with greater exposure than that for plasma were liver (16 times), kidney (3 times), and large intestine (2 times). The exposure for small intestine, lung, and spleen were equivalent to that for plasma. Organs with lower levels of exposure were the heart (0.3 times that for plasma), thigh (0.2 times), and brain (0.06 times). Kinetically, drug was cleared more slowly from all tissues than from plasma, indicating that terminal-phase equilibrium had not been achieved by 24 h. Thus, some measure of accumulation is predicted for all tissues. Single daily doses of MK-0991 should provide adequate systemic levels of fungicidal activity as a result of its long half-life pharmacokinetics, wide distribution, and slowly accumulating concentrations in tissue. PMID- 9371331 TI - Heat-induced superaggregation of amphotericin B reduces its in vitro toxicity: a new way to improve its therapeutic index. AB - Superaggregation of amphotericin B (AmB) was previously shown to occur upon heating of solutions at 70 degrees C. In the present study, we demonstrate that heat pretreatment of Fungizone (deoxycholate salt of AmB [AmB-DOC]) solutions induces a drastic decrease in the in vitro toxicity of this antibiotic. Heated AmB-DOC colloidal solutions, which mainly contained superaggregated and monomeric forms of the antibiotic, were strongly less hemolytic than unheated solutions (aggregates and monomers). Thermal pretreatment of AmB-DOC solutions also reduced the toxicity to the cell line HT29, as deduced from two simultaneous cell viability assays (3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase release). These heated colloidal solutions were only slightly less efficient than the unheated ones at inhibiting the growth of Candida albicans cells in vitro. Such results suggest that mild heat treatment of AmB-DOC solutions could provide a new and simple solution for improving the therapeutic index of this antifungal agent by reducing its toxicity to mammalian cells. PMID- 9371332 TI - Carbapenem resistance in a clinical isolate of Citrobacter freundii. AB - Carbapenem resistance was studied in two sets of Citrobacter freundii strains: (i) strain CFr950, resistant to imipenem (MIC, 16 microg/ml) and isolated in vivo during imipenem therapy, and strain CFr950-Rev, the spontaneous, imipenem susceptible revertant of CFr950 selected in vitro, and (ii) strains CFr801 and CFr802, two imipenem-resistant mutants selected in vitro from the susceptible clinical isolate CFr800. In all strains, whether they were imipenem-susceptible or -resistant strains, production of the cephalosporinase was derepressed and their Km values for cephaloridine were in the range of 128 to 199 microM. No carbapenemase activity was detected in vitro. The role of cephalosporinase overproduction in the resistance was demonstrated after introduction of the ampD gene which decreased the level of production of cephalosporinase at least 250 fold and resulted in an 8- to 64-fold decrease in the MICs of the carbapenems. The role of reduced permeability in the resistance was suggested by the absence, in CFr950 and CFr802, of two outer membrane proteins (the 42- and 40-kDa putative porins whose levels were considerably decreased in CFr801) and the reappearance of the 42-kDa protein in imipenem-susceptible strain CFr950-Rev. This role was confirmed after introduction of the ompF gene of Escherichia coli into the CFr strains, which resulted in 8- to 16-fold decreases in the MICs of carbapenems for CFr802 and CFr950. We infer from these results that the association of reduced, porin-mediated permeability with high-level cephalosporinase production, observed previously in other gram-negative bacteria, may also confer carbapenem resistance on C. freundii. PMID- 9371333 TI - Cloning and characterization of the fmt gene which affects the methicillin resistance level and autolysis in the presence of triton X-100 in methicillin resistant Staphylococcus aureus. AB - In methicillin-resistant Staphylococcus aureus (MRSA) strains, Triton X-100 reduced the oxacillin resistance level, although the degree of reduction varied from strain to strain. To study the responses of MRSA strains to Triton X-100, we isolated a Tn551 insertion mutant of the COL strain that became more susceptible to oxacillin in the presence of 0.02% Triton X-100. The Tn551 insertion of the mutant was transduced back to the parent strain, other MRSA strains (strains KSA8 and NCTC 10443), and methicillin-susceptible strain RN450. All transductants of MRSA strains had reduced levels of resistance to oxacillin in the presence of 0.02% Triton X-100, while those of RN450 did not. Tn551 mutants of KSA8 and NCTC 10443 also had reduced levels of resistance in the absence of 0.02% Triton X-100. The autolysis rates of the transductants in the presence of 0.02% Triton X-100 were significantly increased. Amino acid analysis of peptidoglycan and testing of heat-inactivated cells for their susceptibilities to several bacteriolytic enzymes showed that there were no significant differences between the parents and the respective Tn551 mutants. The Tn551 insertion site mapped at a location different from the previously identified fem and llm sites. Cloning and sequencing showed that Tn551 had inserted at the C-terminal region of a novel gene designated fmt. The putative Fmt protein showed a hydropathy pattern similar to that of S. aureus penicillin-binding proteins and contained two of the three conserved motifs shared by penicillin-binding proteins and beta-lactamases, suggesting that fmt may be involved in cell wall synthesis. PMID- 9371334 TI - Inhibitory activities of quinolones against DNA gyrase and topoisomerase IV purified from Staphylococcus aureus. AB - In order to clarify the mechanism of action of quinolones against Staphylococcus aureus, GrlA and GrlB proteins of topoisomerase IV encoded by genes with or without mutations were purified separately as fusion proteins with maltose binding protein in Escherichia coli. The reconstituted enzymes showed ATP dependent decatenation and relaxing activities but had no supercoiling activity. The inhibitory effects of quinolones on the decatenation activity of topoisomerase IV were determined by quantitative electrophoresis with kinetoplast DNA as a substrate. The 50% inhibitory concentrations (IC50s) of levofloxacin, DR 3354, DU-6859a, DV-7751a, ciprofloxacin, sparfloxacin, and tosufloxacin against topoisomerase IV of S. aureus FDA 209-P were 2.3, 97, 0.45, 1.5, 2.5, 7.4, and 1.8 microg/ml, respectively, and were correlated well with their MICs. The IC50s of these drugs were from 2 to 20 times lower than those for the DNA gyrase. These results support genetic evidence that the primary target of new quinolones is topoisomerase IV in quinolone-susceptible strains of S. aureus. Three altered proteins of topoisomerase IV containing Ser-->Phe changes at codon 80 or Glu- >Lys changes at codon 84 of grlA, or both, were also purified. The inhibitory activities of quinolones against the topoisomerase IV which contained a single amino acid change were from 8 to 95 times weaker than those against the nonaltered enzyme. These results suggest that the mutations in the corresponding genes confer quinolone resistance. PMID- 9371335 TI - In vitro combination of PNU-140690, a human immunodeficiency virus type 1 protease inhibitor, with ritonavir against ritonavir-sensitive and -resistant clinical isolates. AB - PNU-140690 (sulfonamide-containing 5,6-dihydro-4-hydroxy-2-pyrone) is a potent, nonpeptidic inhibitor of the human immunodeficiency virus type 1 (HIV-1) protease currently under clinical evaluation. PNU-140690 and ritonavir were studied in two drug combinations against the replication of HIV-1 clinical isolates in peripheral blood mononuclear cells. A ritonavir-sensitive (301-1x) and -resistant (301-6x) isolate pair derived from an individual before and after monotherapy with ritonavir were used. These isolates showed no significant difference in sensitivity to PNU-140690, but isolate 301-6x was more than 50-fold less sensitive to ritonavir than isolate 301-1x. Mathematical analysis showed that the combination of various concentrations of PNU-140690 with ritonavir yielded additive to moderately synergistic antiviral effects against the ritonavir sensitive isolate and stronger synergy against the ritonavir-resistant isolate. The mechanism of synergy was not investigated, but the results suggested that both the virological and the observed in vitro pharmacological effects may have contributed to the observed synergy. Importantly, no significant antagonism was observed with the drug combinations studied. These data suggest that PNU-140690 may be useful in combination regimens with a structurally unrelated protease inhibitor such as ritonavir. PMID- 9371336 TI - Characterization of a new TEM-derived beta-lactamase produced in a Serratia marcescens strain. AB - A natural TEM variant beta-lactamase was isolated from an epidemic strain of Serratia marcescens. Nucleotide gene sequencing revealed multiple point mutations located in the 42-to-44 tripeptide and positions 145 to 146, 178, and 238. In addition, a glutamic acid 212 deletion was also found. The purified enzyme was studied from a kinetic point of view, revealing the highest catalytic efficiency (k[cat]/Km) values for ceftazidime and aztreonam compared with the TEM-1 prototype enzyme. The in vitro resistance correlated with kinetic parameters, and the enzyme also mediated resistance to some penicillins and an ampicillin clavulanic acid combination. The mutational and kinetic changes are discussed in relation to the three-dimensional crystallographic structure of the wild-type TEM 1 enzyme. PMID- 9371337 TI - Human immunodeficiency virus type 1 proteinase resistance to symmetric cyclic urea inhibitor analogs. AB - Resistant virus was isolated from virus propagated in cell culture in the presence of the human immunodeficiency virus type 1 (HIV-1) proteinase inhibitor DMP 323, Ro 31-8959, or A-75925. The proteinase gene of resistant virus was sequenced, and key mutations (G48V, V82A, I84V, L90M, and G48V/L90M) were introduced into clones used for the expression, purification, and further characterization of the enzyme. The mutant enzymes were all less active than the wild-type enzyme, as judged by k(cat) and k(cat)/Km values. L90M had a lower Km than the wild type, whereas the G48V/L90M double mutant had an increased Km compared with that of the wild type, contributing to a 10-fold reduction in the k(cat)/Km. Vitality values were used to show that the enzyme of the I84V mutant is the enzyme most resistant to the two cyclic urea inhibitors DMP 323 and AHA 008. Virus with the same mutation is also resistant, although the double mutation L10F/I84V confers even greater resistance. All of these mutants are more resistant to DMP 323 than to AHA 008. The resistance of the I84V mutant may be attributed to a loss of van der Waals interactions with the inhibitor, since the larger amino acid side chain involved in the interaction is replaced by a smaller side chain. This is supported by the lower level of resistance to AHA 008 that was observed. The phenyl groups of AHA 008 should protrude deeper into the S1 and S1' subsites than those of the smaller compound DMP 323, reducing the loss of interaction energy. These results reveal that small structural modifications of inhibitors that do not affect the inhibitory effect on wild-type virus can influence the inhibition of resistant strains. This is of importance for optimizing drugs with respect to their potency and resistance. PMID- 9371338 TI - Characterization of fluoroquinolone-induced Achilles tendon toxicity in rats: comparison of toxicities of 10 fluoroquinolones and effects of anti-inflammatory compounds. AB - Fluoroquinolone antibacterial agents have been reported to induce tendon lesions in juvenile rats. In the present study, we characterized fluoroquinolone-induced Achilles tendon lesions by comparing the effects of 10 fluoroquinolones and examining the potential of one of these antimicrobial agents, pefloxacin, to induce tendon lesions when coadministered with one of nine anti-inflammatory compounds. Among the 10 fluoroquinolones tested, fleroxacin and pefloxacin were the most toxic, inducing lesions at a dose of 100 mg/kg of body weight or more, while lomefloxacin, levofloxacin, and ofloxacin or sparfloxacin and enoxacin induced lesions at 300 mg/kg or more and 900 mg/kg, respectively. In contrast, norfloxacin, ciprofloxacin, and tosufloxacin had no effect even at the high dose of 900 mg/kg. The severity of the Achilles tendon lesions appeared to correlate with the structure of the substituent at the seventh position. Furthermore, pefloxacin-induced tendon lesions were inhibited by coadministration with dexamethasone and N-nitro-L-arginine methyl ester. Phenidone (1-phenyl-3 pyrazolidinone) and 2-(12-hydroxydodeca-5,10-diynyl)3,5,6-trimethyl-1,4-benzoqui none (AA861) also decreased the incidence of tendon lesions. In contrast, catalase, dimethyl sulfoxide, indomethacin, pyrilamine, and cimetidine did not modify these tendon lesions. These results suggest that nitric oxide and 5 lipoxigenase products partly mediate fluoroquinolone-induced tendon lesions. PMID- 9371339 TI - Novel antimicrobial peptides derived from human immunodeficiency virus type 1 and other lentivirus transmembrane proteins. AB - We have previously described a conserved set of peptides derived from lentiviral envelope transmembrane proteins that are similar to the natural antimicrobial peptides cecropins and magainins in overall structure but bear no sequence homology to them or other members of their class. We describe here an evaluation of the antimicrobial properties of these virally derived peptides, designated lentivirus lytic peptides (LLPs). The results of this study demonstrate that they are potent and selective antibacterial peptides: the prototype sequence, LLP1, is bactericidal to both gram-positive and gram-negative organisms at micromolar concentrations in 10 mM phosphate buffer. Furthermore, LLP1 kills bacteria quite rapidly, causing a 1,000-fold reduction in viable organisms within 50 s. Peptides corresponding to sequences from three lentivirus envelope proteins were synthesized and characterized. Several of these peptides are selective, killing bacteria at concentrations 50- to 100-fold lower than those required to lyse erythrocytes. Development of antimicrobial agents based on these peptides may lead to improved therapeutics for the management of a variety of infectious diseases. PMID- 9371340 TI - Characterization of the penA and penR genes of Burkholderia cepacia 249 which encode the chromosomal class A penicillinase and its LysR-type transcriptional regulator. AB - Burkholderia cepacia is recognized as an important pathogen in the lung infections of patients with cystic fibrosis. An inducible beta-lactamase activity has been associated with increased resistance to beta-lactam antibiotics in clinical isolates of B. cepacia. In this study, we report the revised sequence of the penA gene, which encodes the inducible penicillinase of B. cepacia, and show that it belongs to the molecular class A beta-lactamases and exhibits a high degree of similarity to the chromosomal beta-lactamase of Klebsiella oxytoca. Analysis of the nucleotide sequence of the DNA region directly upstream of the penA coding sequence revealed an open reading frame (penR), the transcription of which was oriented opposite to that of penA and whose initiation was 130 bp away from that of penA. Two potential ribosome-binding sites and two overlapping -10 and -35 promoter sequences were identified in the intercistronic region. The predicted translation product of penR was a polypeptide of 301 amino acids with an estimated molecular size of 33.2 kDa. The deduced polypeptide of penR showed a high degree of similarity with AmpR-like transcriptional activators of class A and C beta-lactamases, with identities of 59 and 58.7% with Pseudomonas aeruginosa PAO1 AmpR and Proteus vulgaris B317 CumR, respectively. The N-terminal portion of B. cepacia PenR was predicted to include a helix-turn-helix motif, which may bind the LysR motif identified in the intercistronic region. Induction of PenA by imipenem was shown to be dependent upon the presence of PenR. Expression of the cloned B. cepacia penA and penR genes in Escherichia coli SNO302 (ampD) resulted in a high basal and hyperinducible PenA activity. These results suggest that the regulation of the PenA penicillinase of B. cepacia 249 is similar to that observed in other class A and class C beta-lactamases that are under the control of a divergently transcribed AmpR-like regulator. PMID- 9371341 TI - Mutations in the dihydrofolate reductase gene of trimethoprim-resistant isolates of Streptococcus pneumoniae. AB - Streptococcus pneumoniae isolates resistant to several antimicrobial agent classes including trimethoprim-sulfamethoxazole have been reported with increasing frequency throughout the world. The MICs of trimethoprim, sulfamethoxazole, and trimethoprim-sulfamethoxazole (1:19) for 259 clinical isolates from South Africa were determined, and 166 of these 259 (64%) isolates were resistant to trimethoprim-sulfamethoxazole (MICs > or =20 mg/liter). Trimethoprim resistance was found to be more strongly correlated with trimethoprim-sulfamethoxazole resistance (correlation coefficient, 0.744) than was sulfamethoxazole resistance (correlation coefficient, 0.441). The dihydrofolate reductase genes from 11 trimethoprim-resistant (MICs, 64 to 512 microg/ml) clinical isolates of Streptococcus pneumoniae were amplified by PCR, and the nucleotide sequences were determined. Two main groups of mutations to the dihydrofolate reductase gene were found. Both groups shared six amino acid changes (Glu20-Asp, Pro70-Ser, Gln81-His, Asp92-Ala, Ile100-Leu, and Leu135-Phe). The first group included two extra changes (Lys60-Gln and Pro111-Ser), and the second group was characterized by six additional amino acid changes (Glu14-Asp, Ile74-Leu, Gln91-His, Glu94-Asp, Phe147-Ser, and Ala149-Thr). Chromosomal DNA from resistant isolates and cloned PCR products of the genes encoding resistant dihydrofolate reductases were capable of transforming a susceptible strain of S. pneumoniae to trimethoprim resistance. The inhibitor profiles of recombinant dihydrofolate reductase from resistant and susceptible isolates revealed that the dihydrofolate reductase from trimethoprim-resistant isolates was 50-fold more resistant (50% inhibitory doses [ID50s], 3.9 to 7.3 microM) than that from susceptible strains (ID50s, 0.15 microM). Site-directed mutagenesis experiments revealed that one mutation, Ile100-Leu, resulted in a 50-fold increase in the ID50 of trimethoprim. The resistant dihydrofolate reductases were characterized by highly conserved redundant changes in the nucleotide sequence, suggesting that the genes encoding resistant dihydrofolate reductases may have evolved as a result of inter- or intraspecies recombination by transformation. PMID- 9371343 TI - Semiquantitation of cooperativity in binding of vancomycin-group antibiotics to vancomycin-susceptible and -resistant organisms. AB - The association of vancomycin group antibiotics with the growing bacterial cell wall was investigated by using the cell wall precursor analog di-N-acetyl-Lys-D Ala-D-Ala in competition binding experiments. The affinities of the antibiotics for the -D-Ala-D-Ala-containing cell wall precursors of Bacillus subtilis ATCC 6633 (a model for vancomycin-susceptible gram-positive bacteria) and for the -D Ala-D-Lac-containing cell wall precursors of Leuconostoc mesenteroides (a model for vancomycin-resistant strains of Enterococcus faecium and Enterococcus faecalis) were determined by a whole-cell assay. The binding of strongly dimerizing antibiotics such as eremomycin to the bacterial surface was thus shown to be enhanced by up to 2 orders of magnitude (relative to the binding in free solution) by the chelate effect, whereas weakly dimerizing antibiotics like vancomycin and antibiotics carrying lipid tails (teicoplanin) benefited less (ca. 1 order of magnitude). The affinity measured in this way correlates well with the MIC of the antibiotic, and a consequence of this is that future design of semisynthetic vancomycin-group antibiotics should attempt to incorporate chelate effect-enhancing structural features. PMID- 9371342 TI - Pharmacodynamics and bactericidal activity of ceftriaxone therapy in experimental cephalosporin-resistant pneumococcal meningitis. AB - Adequate concentrations of beta-lactam antibiotics in cerebrospinal fluid (CSF) are difficult to achieve for meningitis caused by drug-resistant Streptococcus pneumoniae. Ceftriaxone in dosages of 150 or 400 mg/kg of body weight per day, given in one or two doses, was used for the treatment of experimental highly cephalosporin-resistant (MIC and MBC, 4 microg/ml) pneumococcal meningitis. The bacterial killing rate (delta log10 CFU per milliliter per hour) and pharmacokinetic indices, including percentage of time the antibiotic concentration exceeded the MBC during a 24-h period (T>MBC), CSF peak concentration above the MBC, and area under the concentration-time curve from 0 to 24 h above MBC, were measured and correlated. By multiple stepwise regression, only T>MBC independently predicted the bacterial killing rate. There was a direct linear correlation between T>MBC in CSF and the bacterial killing rate during the first 24 h of therapy (r = 0.87; P = 0.004). Sterilization of CSF was achieved only when the T>MBC was 95 to 100%. In the first 24 h, the 200-mg/kg/12-h regimen, compared with the 400-mg/kg/24-h regimen, was associated with a greater T>MBC (87% +/- 10% versus 60% +/- 22%; P = 0.03) and greater bacterial killing rate (0.2 +/- 0.04 versus 0.13 +/- 0.07; P = 0.003), confirming that ceftriaxone exhibits time-dependent bactericidal activity. After 24 h, the T>MBC and the CSF sterilization rates were similar whether ceftriaxone was given once or twice daily. PMID- 9371344 TI - Pharmacokinetics of cefepime during continuous venovenous hemodiafiltration. AB - The objective of this study was to analyze the pharmacokinetics of cefepime, in six patients with acute renal failure related to septic shock, during continuous venovenous hemodiafiltration (CVVHD) (Hemospal AN 69S hemofilter; Hospal, Lyon, France). Six patients, mean age 65 +/- 4 years (range, 61 to 69), were included and each received 2 g of cefepime by intravenous infusion over a 30-min period every 12 h. Prefilter serum, dialysate outlet (DO), and ultrafiltrate samples were collected 0.47, 0.50, 0.57, 1, 3, 5, 7, and 12 h after the beginning of infusion. The time design of samples was optimized in accordance with the theory of D optimality. The cefepime concentrations were measured by high-performance liquid chromatography. The pharmacokinetics computation was carried out using P PHARM software. Mean serum concentration peaks were 53 +/- 21.9 mg/liter (range, 13.0 to 68.9) one-half hour after the infusion. The mean elimination half-life was 8.11 +/- 2.22 h (range, 4.76 to 10.84). DO clearance was 66.57 +/- 30.14 ml/min (range, 38.66 to 119.87). The mean volume of distribution was 0.71 +/- 0.37 liters/kg of body weight. CVVHD was effective for cefepime elimination. In these subjects, the elimination half-life and DO clearance were almost constant. The results of this study suggested that a 2-g twice-daily infusion (usual dosage) was required for an effective concentration in this group of patients. PMID- 9371345 TI - Pharmacokinetics of saquinavir, zidovudine, and zalcitabine in combination therapy. AB - We investigated the pharmacokinetics of zidovudine, zalcitabine, and saquinavir in AIDS Clinical Trial Group protocol 229. Patients received either saquinavir, zalcitabine, or a combination of both, together with zidovudine three times a day. Approximately 100 patients were enrolled in each treatment arm, and intensive pharmacokinetic studies were performed on about 25 patients per arm at weeks 1 and 12. We estimated the pharmacokinetic parameters of all three drugs by using parametric and nonparametric methods. The mean values of the pharmacokinetic parameters of zidovudine (clearance [CL]/bioavailability [F], 168 liters/h; volume of distribution [V]/F, 185 liters; half-life, 0.76 h) and zalcitabine (CL/F, 25 liters/h; V/F, 92.2 liters; half-life, 2.7 h) were similar to those reported previously. For saquinavir, the mean pharmacokinetic parameter estimates using parametric methods were as follows: maximum concentration of drug in serum [Cmax], 70.8 ng/ml; time to Cmax, 3.11 h; area under the curve, 809 ng x h/ml; CL/F, 989 liters/h; V/F, 1,503 liters; half-life, 1.38 h. For all three drugs, clearance decreased with age. Weight did not influence the clearance of zidovudine, but the clearance of zalcitabine and saquinavir increased with weight. There were no differences in pharmacokinetic parameters between study weeks and arms, suggesting that there is no change in kinetics with chronic administration and that there are no significant pharmacokinetic interactions among these three drugs. PMID- 9371346 TI - Exposure-response relationships for saquinavir, zidovudine, and zalcitabine in combination therapy. AB - The relationship of CD4+ cell response, level of RNA in plasma, and quantitative peripheral blood mononuclear cell (PBMC) titer to apparent drug exposure was investigated by using data from AIDS Clinical Trial Group protocol 229, a multicenter randomized study. Patients received either saquinavir, zalcitabine, or a combination of both, along with open-label zidovudine. Approximately 100 patients were enrolled in each arm, and the primary study duration was 24 weeks. Individual drug exposure, the area under the concentration-time curve, was estimated by using population-based pharmacokinetic methods. Response was defined as the maximum increase in CD4+ cell count or the maximum decrease in RNA in plasma or PBMC titer adjusted for baseline CD4+ cell count, RNA in plasma, and PBMC titer, respectively. Regression of responses on exposure demonstrated an exposure effect for saquinavir which was significant for the maximum increase in CD4+ cell count and the decrease in RNA in plasma. For the PBMC titer, no significant relationship could be demonstrated but the results suggested a trend similar to that of the other response variables. For all three response variables, the slope of the saquinavir exposure response was greater with the triple combination (saquinavir, zidovudine, and zalcitabine) than with the combination of saquinavir and zidovudine, suggesting possible synergism between saquinavir and zalcitabine. PMID- 9371347 TI - Cloning and characterization of an aminoglycoside 6'-N-acetyltransferase gene from Citrobacter freundii which confers an altered resistance profile. AB - A novel gene encoding a 6'-N-aminoglycoside acetyltransferase, aac(6')-In, has been cloned and sequenced from Citrobacter freundii 13996-19, a clinical isolate from Venezuela. This gene mediates resistance to amikacin, 2'-N-ethylnetilmicin, isepamicin, kanamycin, netilmicin, and tobramycin. The aac(6')-In gene is 573 nucleotides in length and encodes a putative protein of 190 amino acids. AAC(6') In is most closely related to AAC(6')-Im and AAC(6')-Ie, demonstrating 64.4% and 62.3% similarity, respectively, at the protein level, suggesting these proteins share a common ancestor. The aac(6')-In flanking sequences demonstrated homology to integron- and transposon-related elements which are often found associated with resistance determinants. Hybridization studies performed with an intragenic probe specific for aac(6')-In indicate that this gene is prevalent within Venezuela but has not been observed outside of the country. Furthermore, the aac(6)-In gene was found in 10 different species of gram-negative bacteria. PMID- 9371348 TI - Efficacy of enrofloxacin or doxycycline for treatment of Bartonella henselae or Bartonella clarridgeiae infection in cats. AB - Enrofloxacin and doxycycline are antimicrobial agents used to treat bacterial diseases of cats. In vitro susceptibility data indicate that either drug should be effective against Bartonella species. In vivo efficacies of these drugs for eradication of chronic Bartonella henselae or Bartonella clarridgeiae infections were examined in 18 experimentally infected cats and 25 naturally exposed cats treated with enrofloxacin (22.7 mg given orally [PO] every 12 h [q12h] [14 days, n = 10; 28 days, n = 13]) or with doxycycline (25 mg PO q12h [14 days, n = 9; 28 days, n = 8]) or not treated (n = 3). Plasma drug concentrations were determined in experimental cats by high-performance liquid chromatography. Only 23 of 43 cats enrolled ultimately met inclusion criteria. Bacteremia was eliminated for 12 to 25 weeks posttreatment in four of seven cats receiving 14 days of enrofloxacin, five of seven cats receiving 28 days of enrofloxacin, one of six cats receiving 14 days of doxycycline, and one of two cats receiving 28 days of doxycycline. Defining a negative result by blood culture as treatment success may be erroneous; these results may reflect the insensitivity of blood culture or the relapsing nature of Bartonella bacteremia. Our results suggest that MICs obtained with axenic media do not predict antimicrobial activity against intracellular Bartonella, that a long treatment course is required to eliminate infection, and that duration of therapy correlates with pretreatment bacterial load. Given current concern about the development of antimicrobial resistance, we would reserve recommendation for treatment to cats owned by an immunocompromised individual or as an alternative to euthanasia of a pet. PMID- 9371349 TI - Ribosylative inactivation of rifampin by Mycobacterium smegmatis is a principal contributor to its low susceptibility to this antibiotic. AB - Mycobacterium smegmatis inactivates rifampin by ribosylating this antibiotic. The gene responsible for this ability was cloned and was shown to confer low-level resistance to this antibiotic (MIC increase, about 12-fold) in related organisms. A 600-bp subclone responsible for ribosylating activity and resistance carried an open reading frame of 429 bp. Targeted disruption of the gene in M. smegmatis resulted in mutants with much increased susceptibility to rifampin (MICs of 1.5 instead of 20 microg/ml) as well as the loss of antibiotic-inactivating ability. Also, disruption of this gene led to a much lower frequency of occurrence of spontaneous high-level rifampin-resistant mutants. PMID- 9371350 TI - Regulation of heme polymerizing activity and the antimalarial action of chloroquine. AB - Mice infected with Plasmodium berghei served as donors of erythrocytes with a high level of parasitemia for the study of ferriprotoporphyrin IX (FP) polymerization. Six hours after treatment of these mice with 3 micromol of chloroquine per 25 g of body weight, there were significant losses of heme polymerase I (HPA I). For chloroquine-susceptible (CS) P. berghei, the rate of FP polymerization decreased from 541 +/- 42 (mean +/- standard deviation; n = 12) to 51 +/- 19 (n = 8) nmol of FP polymerized per h per ml of packed erythrocytes (normalized to represent 1,000 parasites per 1,000 erythrocytes). For chloroquine resistant (CR) P. berghei, the rate decreased from 284 +/- 19 (n = 16) to 124 +/- 11 (n = 6) nmol per h per ml. The chloroquine-induced loss of HPA I was accompanied by the accumulation of unpolymerized FP in CS P. berghei but not in CR P. berghei, which is consistent with the hypothesis that FP mediates the antimalarial action of chloroquine. Quinine treatment partially reversed the effects of chloroquine in CS P. berghei but not in CR P. berghei. Cycloheximide treatment antagonized the effects of chloroquine in both lines of parasites. To explain these findings, we propose that chloroquine, quinine, and cycloheximide perturb a regulatory process for HPA I. Furthermore, we propose that when chloroquine engages its target in the regulatory process, it initiates a chain of events which culminates in increased production, accessibility, or reactivity of a regulator (inactivator) of HPA I. PMID- 9371351 TI - Effects of moderate-dose versus high-dose trimethoprim on serum creatinine and creatinine clearance and adverse reactions. AB - The effects of a 10-day course of moderate-dose (10 mg/kg/day) or high-dose (20 mg/kg/day) trimethoprim therapy on serum creatinine, measured creatinine clearance, urinary creatinine excretion, and serum folate were studied in 20 healthy volunteers. Serum creatinine concentrations increased significantly during trimethoprim therapy, began to decrease near day 10, and returned to baseline during the washout phase at both dosage levels. At the same time, measured creatinine clearance and urine creatinine changed in the opposite direction. No clinical or statistical differences were noted between changes in the moderate- versus the high-dose phases. Serum folate concentration decreases during high-dose trimethoprim therapy were statistically significant. Adverse drug reactions in the two groups were statistically different during the first study period, with the high-dose group having a 75% incidence rate and the moderate-dose group having an 11% incidence rate (P < 0.02). Serum creatinine, measured creatinine clearance, and urinary creatinine excretion demonstrated statistically, but not clinically, significant changes during trimethoprim therapy. In addition, high-dose trimethoprim caused significantly more adverse drug reactions than moderate-dose trimethoprim in normal volunteers. PMID- 9371352 TI - Identification of the FKS1 gene of Candida albicans as the essential target of 1,3-beta-D-glucan synthase inhibitors. AB - Pneumocandins and echinocandins are fungicidal antibiotics, currently in clinical development, that inhibit 1,3-beta-D-glucan synthase (GS) in several human fungal pathogens. We have identified a gene from the diploid organism Candida albicans that encodes a target of these inhibitors. A 2.1-kb portion of this gene, designated CaFKS1, has significant homology to the Saccharomyces cerevisiae FKS1 and FKS2 genes, which encode partially functionally redundant subunits of GS. To evaluate the role of CaFkslp in susceptibility to echinocandins, we disrupted CaFKS1 on one homolog each of the spontaneous pneumocandin-resistant C. albicans mutants CAI4R1, NR2, NR3, and NR4. These mutants had been selected previously on agar plates containing the pneumocandin L-733,560. The clones derived from this transformation were either resistant (Ech[r]) or fully sensitive (Ech[s]) to inhibition by L-733,560 in both liquid broth microdilution and in vitro GS assays. The site of plasmid insertion in the transformants was mapped by Southern blot analysis, using restriction site polymorphisms in the CaFKS1 gene to distinguish between the two alleles (designated CaFKS1h and CaFKS1b). For strains CAI4R1 and NR2, the CaFKS1b allele was disrupted in each Ech(r) transformant; for strain NR4, CaFKS1h was disrupted in each Ech(r) transformant. We conclude that (i) strains CAI4R1, NR2, and NR4 are heterozygous for a dominant or semidominant pneumocandin resistance mutation at CaFKS1, (ii) drug resistance mutations can occur in either CaFKS1 allele, and (iii) CaFks1p is a target of the echinocandins. For transformants of strain NR3, all the clones we analyzed were uniformly Ech(r), and only the CaFKS1h allele, either in disrupted or wild-type form, was detected on genomic Southern blots. We believe gene conversion at the CaFKS1 locus may have produced two Cafks1h alleles that each contain an Ech(r) mutation. Transformants derived from the mutants were analyzed for susceptibility to pneumocandin treatment in a mouse model of disseminated candidiasis. Strains heterozygous for the resistant allele (i.e., C. albicans CAI4R1, NR2, and NR4) were moderately resistant to treatment, while strains without a functional Ech(s) allele (i.e., strain NR3 and derivatives of strain CAI4R1 with the disruption plasmid integrated in the Ech[s] allele) displayed strong in vivo echinocandin resistance. Finally, we were unable to inactivate both alleles at CaFKS1 by two step integrative disruption, suggesting that CaFks1p is likely to be an essential protein in C. albicans. PMID- 9371353 TI - Pharmacokinetic interaction of megestrol acetate with zidovudine in human immunodeficiency virus-infected patients. AB - This nonrandomized, two-period crossover study was performed to assess whether concomitant administration of megestrol acetate influences the steady-state pharmacokinetics of zidovudine and its inactive 5'-O-glucuronide metabolite. Twelve HIV-positive, asymptomatic male volunteers received a 100-mg oral capsule dose of zidovudine at least 30 min before meals five times a day at 0700, 1100, 1500, 1900, and 2300 h on study days 1 to 3 and a single 100-mg dose at 0700 h on day 4. On days 5 to 17, 800 mg of megestrol acetate, as a 40-mg/ml aqueous suspension, was administered orally immediately before the 0700 h dose of zidovudine. On days 5 to 16, zidovudine was also administered at 1100, 1500, 1900, and 2300 h. Serial blood samples were collected for 12 h after the single 100-mg dose of zidovudine on days 4 and 17; trough samples were also obtained just before the 0700 h dose on days 2 to 4 and 15 to 17. Levels of zidovudine and its glucuronide in plasma were assayed by a validated radioimmunoassay. Statistical analysis of trough plasma level data indicated that steady-state levels of zidovudine and its glucuronide in plasma had been attained when pharmacokinetic assessments were made on days 4 and 17. When megestrol acetate and zidovudine were coadministered for 13 days, differences of -14, -6.5, and 4.6% in mean zidovudine peak concentration and areas under the curve at 0 to 4 and 0 to 12 h, respectively, +22.5% in mean trough concentration, +2.6% in mean plasma half-life, and no change in median time to peak were observed compared to conditions when zidovudine was administered alone; for zidovudine 5'-O glucuronide the respective differences were -9, -7.3, -4.4, +2.3, and +10% and no change. None of the differences were statistically significant (P > 0.05). Concomitant therapy with megestrol acetate, at the dose employed to treat anorexia, cachexia, or an unexplained, significant weight loss in AIDS patients, did not alter the steady-state pharmacokinetics of zidovudine or its 5'-O glucuronide metabolite. PMID- 9371354 TI - Limiting deoxynucleoside triphosphate concentrations emphasize the processivity defect of lamivudine-resistant variants of human immunodeficiency virus type 1 reverse transcriptase. AB - The nucleoside drug lamivudine (3TC) triggers the selection of resistant forms of the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) with a substitution of amino acid 184Met. The 3TC-resistant RT enzymes 184Val and 184Ile exhibit a processivity defect in in vitro assays that correlates with reduced replication of the corresponding virus variants in primary cells. However, no replication defect is apparent for these two mutants in the transformed T-cell line SupT1. One obvious difference between the two cell types is the intracellular deoxynucleoside triphosphate (dNTP) level. Primary cells have a much smaller dNTP pool, and this cellular condition may emphasize the processivity defect of the codon 184 RT variants. Alternatively, cell-specific cofactors that influence the process of reverse transcription may exist. Such accessory factors may be packaged into the virion to exert an effect on the RT enzyme. To discriminate between these possibilities we performed additional assays with the wild-type and mutant RT enzymes. The RT proteins were either isolated from virions produced by primary and transformed cell types or expressed as recombinant protein. We also performed infection assays with cells treated with a drug that reduces the intracellular dNTP pool. Furthermore, reverse transcription was studied within virus particles in the endogenous assay, which allows for the manipulation of the dNTP level. The combined results indicate that the enzymatic defect of the 3TC-resistant HIV-1 variants is stressed at low dNTP concentrations. PMID- 9371355 TI - A new triazole, voriconazole (UK-109,496), blocks sterol biosynthesis in Candida albicans and Candida krusei. AB - Voriconazole (UK-109,496) is a novel triazole derivative with potent broad spectrum activity against various fungi, including some that are inherently resistant to fluconazole, such as Candida krusei. In this study we compared the effect of subinhibitory concentrations of voriconazole and fluconazole on sterol biosynthesis of fluconazole-resistant and -susceptible Candida albicans strains, as well as C. krusei, in an effort to delineate the precise mode of action of voriconazole. Voriconazole MICs ranged from 0.003 to 4 microg/ml, while fluconazole MICs ranged from 0.25 to >64 microg/ml. To investigate the effects of voriconazole and fluconazole on candidal sterols, yeast cells were grown in the absence and presence of antifungals. In untreated C. albicans controls, ergosterol was the major sterol (accounting for 53.6% +/- 2.2% to 71.7% +/- 7.8% of the total) in C. albicans and C. krusei strains. There was no significant difference between the sterol compositions of the fluconazole-susceptible and resistant C. albicans isolates. Voriconazole treatment led to a decrease in the total sterol content of both C. albicans strains tested. In contrast, exposure to fluconazole did not result in a significant reduction in the total sterol content of the three candidal strains tested (P > 0.5). Gas-liquid chromatographic analysis revealed profound changes in the sterol profiles of both C. albicans strains and of C. krusei in response to voriconazole. This antifungal agent exerted a similar effect on the sterol compositions of both fluconazole susceptible and -resistant C. albicans strains. Interestingly, a complete inhibition of ergosterol synthesis and accumulation of its biosynthetic precursors were observed in both strains treated with voriconazole. In contrast, fluconazole partially inhibited ergosterol synthesis. Analysis of sterols obtained from a fluconazole-resistant C. albicans strain grown in the presence of different concentrations of voriconazole showed that this agent inhibits ergosterol synthesis in a dose-dependent manner. In C. krusei, voriconazole significantly inhibited ergosterol synthesis (over 75% inhibition). C. krusei cells treated with voriconazole accumulated the following biosynthetic intermediates: squalene, 4,14-dimethylzymosterol, and 24 methylenedihydrolanosterol. Accumulation of these methylated sterols is consistent with the premise that this agent functions by inhibiting fungal P-450 dependent 14alpha-demethylase. As expected, treating C. krusei with fluconazole minimally inhibited ergosterol synthesis. Importantly, our data indicate that voriconazole is more effective than fluconazole in blocking candidal sterol biosynthesis, consistent with the different antifungal potencies of these compounds. PMID- 9371357 TI - Comparative metabolism of the antiviral dimer 3'-azido-3'-deoxythymidine-P-2',3' dideoxyinosine and the monomers zidovudine and didanosine by rat, monkey, and human hepatocytes. AB - AZT-P-ddI is an antiviral heterodimer composed of one molecule of 3'-azido-3' deoxythymidine (AZT) and one molecule of 2',3'-dideoxyinosine (ddI) linked through their 5' positions by a phosphate bond. The metabolic fate of the dimer was studied with isolated rat, monkey, and human hepatocytes and was compared with that of its component monomers AZT and ddI. Upon incubation of double labeled [14C]AZT-P-[3H]ddI in freshly isolated rat hepatocytes in suspension at a final concentration of 10 microM, the dimer was taken up intact by cells and then rapidly cleaved to AZT, AZT monophosphate, ddI, and ddI monophosphate. AZT and ddI so formed were then subject to their respective catabolisms. High-performance liquid chromatography analyses of the extracellular medium and cell extracts revealed the presence of unchanged dimer, AZT, 3'-azido-3'-deoxy-5'-beta-D glucopyranosylthymidine (GAZT), 3'-amino-3'-deoxythymidine (AMT), ddI, and a previously unrecognized derivative of the dideoxyribose moiety of ddI, designated ddI-M. Trace extracellular but substantial intracellular levels of the glucuronide derivative of AMT (3'-amino-3'-deoxy-5'-beta-D glucopyranosylthymidine [GAMT]) were also detected. Moreover, the extent of the formation of AMT, GAZT, and ddI-M from the dimer was markedly lower than that with AZT and ddI alone by the hepatocytes. With hepatocytes in primary culture obtained from rat, monkey, and human, large interspecies variations in the metabolism of AZT-P-ddI were observed. While GAZT and ddI-M, metabolites of AZT and ddI, respectively, as well as AZT 5'-monophosphate (MP) and ddI-MP were detected in the extracellular media of all species, AMT and GAMT were produced only by rat and monkey hepatocytes. No such metabolites were formed by human hepatocytes. The metabolic fate of the dimer by human hepatocytes was consistent with in vivo data recently obtained from human immunodeficiency virus-infected patients. PMID- 9371356 TI - Pharmacodynamics of vancomycin alone and in combination with gentamicin at various dosing intervals against methicillin-resistant Staphylococcus aureus infected fibrin-platelet clots in an in vitro infection model. AB - We compared the pharmacodynamic activities of vancomycin with or without gentamicin in an in vitro infection model with methicilin-resistant Staphylococcus aureus-infected fibrin-platelet clots. Infected fibrin-platelet clots (FPCs) were prepared with human cryoprecipitate, human platelets, thrombin, and the organism (approximately 10[9] CFU of MRSA-494/g) and were suspended with monofilament line in an infection model capable of simulating human pharmacokinetics. Antibiotics were bolused to simulate vancomycin regimens of 2 g every 24 h (q24h), 1 g q12h, 500 mg q6h, and continuous infusion (steady-state concentration of 20 microg/ml) and gentamicin regimens of 1.5 mg/kg of body weight q12h and 5 mg/kg once daily (q.d.). Model experiments were performed in duplicate over 72 h. FPCs were removed from the models in quadruplicate at 0, 8, 24, 32, 48, 72 h, weighed, homogenized, diluted, and plated to determine colony counts. The inoculum density at 72 h was used to compare bactericidal activities between the regimens. All regimens containing vancomycin significantly decreased the bacterial inoculum compared to the growth control (P < 0.001). Vancomycin monotherapy regimens were similar in bacterial kill regardless of dosing frequency. The addition of gentamicin (either q12h or q.d.) significantly improved the bactericidal activity of the vancomycin q6h, q12h, and q24h regimens (P < 0.001). The greatest reduction in bacterial density at 72 h (P < 0.001) and the most rapid rate of kill (time to 99.9% killing) were achieved with the regimen consisting of 2 g of vancomycin q24h plus gentamicin (q.d. or q12h). PMID- 9371358 TI - Pharmacokinetics and pharmacodynamics of two multiple-dose piperacillin tazobactam regimens. AB - The pharmacokinetics and pharmacodynamics of two multiple-dose regimens of piperacillin-tazobactam (3.375 g every 6 h and 4.5 g every 8 h) were evaluated at steady state for 12 healthy adult volunteers. Inhibitory and bactericidal activities for the two regimens were determined with five American Type Culture Collection (ATCC) organisms (Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Bacteroides fragilis). The percentage of time that plasma concentrations remained above the MIC (T > MIC) for each organism and dosage regimen was calculated. Areas under the inhibitory (AUIC0-24) and bactericidal activity (AUBC0-24) curves were calculated with the trapezoidal rule by using the reciprocal of the inhibitory and bactericidal titers determined for each dosage regimen. In order to assess the validity of predicted measures of bactericidal (AUC0-24/MBC) and inhibitory (AUC0-24/MIC) activity to determine bacteriological response to beta-lactam antimicrobial agents, AUC0-24/MBC and AUC0-24/MIC values were compared with measured AUBC0-24 and AUIC0-24 values. Total body clearance values were equivalent for piperacillin (183.96 +/- 22.66 versus 181.72 +/- 19.54 ml/min/1.73 m2, P > 0.05) and tazobactam (184.71 +/- 19.89 versus 184.87 +/- 18.35 ml/min/1.73 m2, P > 0.05) following the administration of the 3.375-g-every-6-h and 4.5-g-every-8-h dosages, respectively. Comparison of area under the plasma concentration-time curve (AUC0 24) for piperacillin (967.74 +/- 135.56 microg x h/ml versus 978.88 +/- 140.96 microg x h/ml) and tazobactam (120.14 +/- 15.78 microg x h/ml versus 120.01 +/- 16.22 microg x h/ml) revealed no significant differences (P > 0.05) between the 3.375-g-every-6-h and 4.5-g-every-8-h regimens, respectively. Both regimens provided T > MIC values of > 60% for all organisms tested. Measured values of bactericidal (AUBC) and inhibitory (AUIC) activity were significantly different (P < 0.05) from predicted values (AUC0-24/MBC and AUC0-24/MIC) for all organisms studied with the exception of the bactericidal activity for P. aeruginosa and S. aureus. Additionally, ATCC organisms possessing the same MICs and MBCs exhibited great differences in measured AUBC0-24 and AUIC0-24 values. Reasons for this difference may be inherent differences in organism specific susceptibility. PMID- 9371359 TI - Effectiveness of quinolone antibiotics in modulating the effects of antifungal drugs. AB - Quinolone antibacterial drugs inhibit DNA gyrase, a type 2 topoisomerase. Since topoisomerases are present in eukaryotic cells, it was of interest to evaluate the antifungal activities of two clinically available quinolones, ciprofloxacin and trovafloxacin, alone and in combination with amphotericin B or fluconazole, in vitro against Candida albicans and in a murine model of invasive candidiasis. The in vitro activity of trovafloxacin was also tested against other yeasts and molds. In vitro, trovafloxacin exhibited no antifungal activity against any of the fungi (MIC, >250 microg/ml). There was also no effect of the quinolone on the in vitro activity of either antifungal drug. Marked antifungal effects were seen, however, in the murine model of candidiasis. In all experiments, control mice infected intravenously with C. albicans were dead by day 24. While either quinolone had minimal effects on survival of mice when used alone in oral doses of up to 40 mg/kg twice daily, the combination of the quinolone with fluconazole (40 or 80 mg/kg given twice daily by oral gavage) was more effective in prolonging survival than was fluconazole alone. Colony counts of kidneys on days 12 and 30 showed similar reductions in C. albicans recovered from mice treated with fluconazole with or without trovafloxacin or amphotericin B with or without trovafloxacin. Survival of mice treated with a suboptimal dose of amphotericin B (0.2 mg/kg/day) was also improved when trovafloxacin (40 mg/kg) given twice daily was included (0 versus 27%, respectively; P < 0.05). While the mechanisms of action of the combination of trovafloxacin and amphotericin B or fluconazole are unclear, further work focused on fungal topoisomerase inhibition and the mechanism of the antifungal effect of quinolone antibacterial drugs is warranted. PMID- 9371361 TI - Comparative bactericidal activity of ceftazidime against isolates of Pseudomonas aeruginosa as assessed in an in vitro pharmacodynamic model versus the traditional time-kill method. AB - Bactericidal activity, historically assessed by in vitro tests which employ fixed drug concentrations, may also be evaluated in in vitro pharmacodynamic models in which in vivo pharmacokinetics and bacterial growth conditions can be simulated. However, systematic comparisons between the two methods are lacking. We evaluated the bactericidal activities of ceftazidime, at two different concentration/MIC ratios (C/MICs), against 10 clinical isolates of Pseudomonas aeruginosa in a two compartment model with continuous-infusion conditions and a 2-h half-life. These values were compared to those determined by traditional 24-h time-kill (TTK) methods at the same C/MICs. Bactericidal activities were compared by using area under the colony count-time curves. Antibiotic exposure (area under the drug concentration-time curve) was also evaluated. Although bactericidal activity appeared greater by the TTK method (P = 0.05), when it was normalized for drug exposure, these differences disappeared (P = 0.2). This disparity was likely due to differences in drug exposure in the TTK method and in the peripheral compartment of the model (site of bacteria) over the first 8 h of the experiment, during which the antibiotic accumulated to target concentrations. This suggests that the bactericidal effects with constant antibiotic concentrations are similar in the two methods; however, this may not hold true with fluctuating drug concentrations. Further, results from the pharmacodynamic model may theoretically be more relevant, as in vivo pharmacokinetics and bacterial growth conditions call be more faithfully simulated. PMID- 9371360 TI - Studies of the killing kinetics of benzylpenicillin, cefuroxime, azithromycin, and sparfloxacin on bacteria in the postantibiotic phase. AB - Most antibiotics are known to be incapable of killing nongrowing or slowly growing bacteria with few exceptions. Bacterial cell division is inhibited during the postantibiotic phase (PA phase) after short exposure to antibiotics. Only scarce and conflicting data are available concerning the ability of antibiotics to kill bacteria in the PA phase. The aim of the present study was to investigate the killing effect of four different antibiotics on bacteria in the PA phase. A postantibiotic effect (PAE) was induced by exposing Streptococcus pyogenes and Haemophilus influenzae to 10x MICs of benzylpenicillin, cefuroxime, sparfloxacin, and azithromycin. The bacteria were thereafter reexposed to a 10x MIC of the same antibiotic used for the induction of the PAE at the beginning of and after 2 and 4 h in the PA phase. Due to a very long PAE, the bacteria in PA phase induced by azithromycin were also exposed to 10x MICs after 6 and 8 h. A previously unexposed culture exposed to a 10x MIC was used as a control. The results seem to be dependent on both the antibiotic used and the bacterial species. The antibiotics exhibiting a fork bactericidal action gave significantly reduced killing of the bacteria in PA phase (cefuroxime with S. pyogenes, P < 0.01, and sparfloxacin with H. influenzae, P < 0.001), which was restored at 4 h for cefuroxime with S. pyogenes. There was a tendency to restoration of the bactericidal activity also with sparfloxacin and H. influenzae, but there was still a significant difference in killing between the control and the test bacteria in PA phase at 4 h. However, in the combinations with a lesser bactericidal effect (benzylpenicillin with S. pyogenes and sparfloxacin with S. pyogenes), there was no difference in killing between the control and the test bacteria in PA phase. Azithromycin induced long PAEs in both S. pyogenes and H. influenzae and exhibited a slower bactericidal action on both the control and the bacteria in PA phase especially at the end of the PAE, when the killing was almost bacteriostatic. Our findings in this study support the concept that a long interval (> 12 h) between doses of azithromycin, restoring full bactericidal action, may be beneficial to optimize efficacy of this drug but is not necessary for the other antibiotics evaluated, since the bactericidal effect seems to be restored already at 4 h. PMID- 9371363 TI - Differential selection of multidrug efflux systems by quinolones in Pseudomonas aeruginosa. AB - Resistance mechanisms selected after in vitro exposure to 12 quinolones were analyzed for Pseudomonas aeruginosa. Efflux-type mutants were predominant. Quinolones differed in their ability to select a particular efflux system. While the newer fluoroquinolones favored the MexCD-OprJ system, the older quinolones selected exclusively the MexEF-OprN or MexAB-OprM systems. A protonable C-7 substituent in combination with a C-6 fluorine atom is a structural determinant of quinolones involved in efflux pump substrate specificity. PMID- 9371362 TI - Naphthylisoquinoline alkaloids against malaria: evaluation of the curative potentials of dioncophylline C and dioncopeltine A against Plasmodium berghei in vivo. AB - Naphthylisoquinoline alkaloid-containing extracts from species of the families Dioncophyllaceae and Ancistrocladaceae and purified alkaloids derived therefrom were shown to exhibit antiparasitic activity in Plasmodium berghei-infected mice. Several extracts and alkaloids, especially dioncophylline C and dioncopeltine A, isolated from Triphyophyllum peltatum (Dioncophyllaceae), displayed high levels of activity. Dioncopeltine A was able to suppress parasitemia almost totally, while dioncophylline C cured infected mice completely after oral treatment with 50 mg kg of body weight(-1) day(-1) for 4 days without noticeable toxic effects. Analysis of the dose-response relationship of dioncophylline C revealed a 50% effective dosage (ED50) of 10.71 mg kg(-1) day(-1) under these conditions. Although four daily treatments with 50 mg kg(-1) day(-1) are needed to achieve radical cure, one oral dose is sufficient to kill 99.6% of the parasites. Intravenous application of dioncophylline C is even more effective, with an ED50 of 1.90 mg kg(-1) day(-1) and no noticeable toxic effects. The compound also suppressed more established P. berghei infections when orally applied at day 3 after infection. Both dioncopeltine A and dioncophylline C are active against the chloroquine-resistant P. berghei Anka CRS parasites. Sustained release of these compounds at 20 mg kg(-1) day(-1) by implanted miniosmotic pumps exhibited curative effects. The naphthylisoquinoline alkaloids are therefore promising new antimalarial agents. PMID- 9371364 TI - Improved antimicrobial activity of DU-6859a, a new fluoroquinolone, against quinolone-resistant Klebsiella pneumoniae and Enterobacter cloacae isolates with alterations in GyrA and ParC proteins. AB - MICs of DU-6859a, a novel fluoroquinolone, for 18 Klebsiella pneumoniae isolates and 21 Enterobacter cloacae isolates with altered GyrA or altered GyrA and ParC ranged from < or =0.025 to 6.25 microg/ml and from 0.1 to 3.13 microg/ml, respectively. Based on the MICs at which 90% of the isolates were inhibited for these strains of K. pneumoniae and E. cloacae, DU-6859a exhibited 16- to 256-fold greater activity than currently available fluoroquinolones. PMID- 9371365 TI - Inhibitor-resistant TEM (IRT) beta-lactamases with different substitutions at position 244. AB - A novel inhibitor-resistant TEM (IRT) beta-lactamase was detected in an Escherichia coli isolate resistant to amoxicillin-clavulanate and susceptible to cephalothin. The substrate and inhibitor profiles of this beta-lactamase were similar to those of IRT-1 and IRT-2. The novel IRT's bla gene was sequenced, and the deduced amino acid sequence showed the amino acid replacement Arg for His-244 of the TEM-1 sequence. Substitutions for Arg-244 have been reported in three TEM 1 mutants: IRT-1 (which corresponds to TEM-31) (Cys), IRT-2/TEM-30 (Ser), and TEM 41 (Thr). We designated this novel beta-lactamase, which corresponds to TEM-51, IRT-15. PMID- 9371366 TI - Macrolide resistance in Helicobacter pylori: mechanism and stability in strains from clarithromycin-treated patients. AB - Helicobacter pylori strains from seven patients treated with clarithromycin were investigated for development, mechanism, and stability of resistance. Genetic relatedness between pre- and posttreatment isolates was shown by arbitrary primed PCR. Clarithromycin resistance was associated with A-to-G transitions at either position 2143 or 2144 or at both positions 2116 and 2142. In four cases, the mutations were homozygous. The Cla(r) phenotype was stable after 50 subcultivations in vitro. No erythromycin-modifying enzymes or rRNA methylases were found by biological assays, PCR and sequencing, or cloning methods. PMID- 9371367 TI - Pharmacokinetics of itraconazole (oral solution) in two groups of human immunodeficiency virus-infected adults with oral candidiasis. AB - The pharmacokinetics of itraconazole formulated in a hydroxypropyl-beta cyclodextrin oral solution was determined for two groups of human immunodeficiency virus (HIV)-infected adults with oral candidiasis (group A, 12 patients with CD4+ T-cell count of >200/mm3 and no AIDS, and group B, 11 patients with CD4+ T-cell count of <100/mm3 and AIDS). Patients received 100 mg of itraconazole every 12 h for 14 days. Concentrations of itraconazole and hydroxyitraconazole, the main active metabolite, were measured in plasma and saliva by high-performance liquid chromatography. Pharmacokinetic parameters determined at days 1 and 14 (the area under the concentration-time curve from 0 to 10 h, the maximum concentration of drug in plasma [Cmax], and the time to Cmax) were comparable in both groups. Trough levels in plasma (Cmin) were similar in both groups for the complete duration of the study. An effective concentration of itraconazole in plasma (>250 ng/ml) was reached at day 4. At day 14, Cmin values of itraconazole were 643 +/- 304 and 592 +/- 401 ng/ml for groups A and B, respectively, and Cmin values of hydroxyitraconazole were 1,411 +/- 594 and 1,389 +/- 804 ng/ml for groups A and B, respectively. In saliva, only unchanged itraconazole was detected, and mean concentrations were still high (>250 ng/ml) 4 h after the intake, which may contribute to the fast clinical response. In conclusion, the oral solution of itraconazole generates effective levels in plasma and saliva in HIV-infected patients; its relative bioavailability is not modified by the stage of HIV infection. PMID- 9371368 TI - Penetration of teicoplanin into heart valves and subcutaneous and muscle tissues of patients undergoing open-heart surgery. AB - Penetration of teicoplanin into serum, heart valves, and subcutaneous and muscle tissues was determined in 22 patients undergoing open-heart surgery. Each patient received 12 mg of teicoplanin per kg of body weight as a 30-min intravenous infusion preoperatively. Within 10 h, serum concentrations of teicoplanin declined from 43.1 to 2.8 microg/ml. Teicoplanin concentrations in subcutaneous tissues reached their peak of 9.2 microg/g after 2 to 3 h and decreased slowly to 2.3 microg/g after 9 to 10 h. Concentrations in muscle decreased from 8.7 microg/g to nondetectable levels. Teicoplanin concentrations in cardiac valvular tissue reached their peak of 6.1 microg/g and decreased thereafter to 1.7 microg/g. Teicoplanin concentrations in heart valves were high enough to inhibit methicillin-resistant Staphylococcus aureus and coagulase-negative staphylococci, which are known to cause postoperative wound infections and infective endocarditis. PMID- 9371369 TI - Effects of ciprofloxacin and ofloxacin on adult human cartilage in vitro. AB - Chondrocyte toxicity and necrosis were seen with electron microscopy after incubation of human adult cartilage biopsy specimens in ciprofloxacin or ofloxacin. In vitro exposure of chondrocytes to fluoroquinolones did not affect apoptosis as determined by flow cytometry. While the immediate clinical significance of this finding remains unclear, the possibility of long-term cartilage damage after fluoroquinolone treatment cannot be excluded. PMID- 9371370 TI - Diazepam-mediated inhibition of human immunodeficiency virus type 1 expression in human brain cells. AB - Treatment of acutely infected human brain cell and enriched microglial cell cultures with diazepam inhibited human immunodeficiency virus type 1 (HIV-1) p24 antigen expression. Similarly, diazepam suppressed HIV-1 expression in chronically infected promonocytic (U1) cells and acutely infected monocyte derived macrophages, and this antiviral activity was associated with decreased activation of nuclear factor kappa B. PMID- 9371371 TI - Structure-activity studies of quinolone-penems in genetically defined strains of Escherichia coli. AB - Quinolonyl-beta-lactam antimicrobial agents (QLAs) contain quinolones chemically linked to beta-lactams, although the impact of linkage is poorly understood. Genetically defined Escherichia coli strains were used to determine structure activity characteristics of three quinolone-penem QLAs. Results suggest that the leaving group resulting from beta-lactam hydrolysis may not be free quinolone. PMID- 9371372 TI - In vitro activities of an investigational quinolone, glycylcycline, glycopeptide, streptogramin, and oxazolidinone tested alone and in combinations against vancomycin-resistant Enterococcus faecium. AB - We evaluated the in vitro activities of clinafloxacin, CL331,002, LY333328, quinupristin dalfopristin, and eperezolid (formerly known as U-100,592) against four strains of enterococci. All regimens tested resulted in the growth inhibition of each isolate. Against the three clinafloxacin-susceptible strains, clinafloxacin tested alone was the most active treatment, decreasing the bacterial inoculum by more than 3 log10 CFU/ml after 24 h in time-kill curve studies. PMID- 9371373 TI - In vitro kill curves of a new semisynthetic echinocandin, LY-303366, against fluconazole-sensitive and -resistant Candida species. AB - In vitro killing by a new semisynthetic echinocandin, LY-303366, was characterized using clinical isolates of fluconazole-sensitive (Y58) and resistant (Y180) Candida albicans as well as Candida glabrata (Y7) and Candida krusei (Y171). The 24-h kill curves for Y58 and Y180 demonstrated dose independent killing of between 1 and 2 log10 with LY-303366 at concentrations of 0.1, 1, 10, 50, 100, and 1,000 times the MIC. Regrowth did not occur at 24 h with either C. albicans isolate at the aforementioned LY-303366 concentrations. At their MICs, LY-303366 and amphotericin B produced similar killing kinetics in cultures of Y58, Y180, Y7, and Y171, while all cultures exposed to fluconazole at its MIC demonstrated stasis or growth over 24 h. PMID- 9371374 TI - Selective inhibition of the duck hepatitis B virus by a new class of tetraazamacrocycles. AB - The antiviral activity of a new class of N,N,N',N",NA'''-pentakis (omega aminoalkyl) tetraazamacrocycles was evaluated in primary duck hepatocyte cultures infected with the duck hepatitis B virus (DHBV). Three of the four tested compounds were able to selectively inhibit DHBV replication by acting at an early step of the hepadnavirus infection but were associated with significant toxicity. PMID- 9371375 TI - In vitro and in vivo antibacterial activities of CS-940, a new fluoroquinolone, against isolates from patients with respiratory infections. AB - We compared the in vivo and in vitro activities of CS-940, a new fluoroquinolone, with those of a group of other drugs. The activities of CS-940 against gram positive cocci and gram-negative rods, including methicillin-susceptible Staphylococcus aureus and penicillin-resistant Streptococcus pneumoniae, were comparable to those of tosufloxacin, with MICs at which 90% of the strains were inhibited (MIC90s) of 0.5 microg/ml or less. Against methicillin-resistant S. aureus, CS-940 was as active as tosufloxacin, with a MIC90 of 16 microg/ml. The efficacy of CS-940 against murine respiratory infections due to S. pneumoniae or Haemophilus influenzae was better than those of tosufloxacin and sparfloxacin. The efficacy of oral doses of CS-940 reflected not only potent in vitro activity but also a high transmigration ratio from the bloodstream to lung tissues. PMID- 9371376 TI - In vitro synergistic activities of tobramycin and selected beta-lactams against 75 gram-negative clinical isolates. AB - The microdilution checkerboard technique was utilized to distinguish synergistic activity between tobramycin and four beta-lactams: piperacillin-tazobactam, ticarcillin-clavulanate, ceftazidime, and ceftriaxone. Beta-lactam-aminoglycoside combinations were tested against 75 clinical isolates of Pseudomonas aeruginosa, Acinetobacter baumanii, Citrobacterfreundii, Serratia marcescens, and Enterobacter cloacae. Despite in vitro susceptibilities, all isolates demonstrated either synergism or indifference; no antagonism was observed. Against pathogenic gram-negative nosocomial isolates, a greater percentage of synergy was consistently observed with combination regimens containing tobramycin and piperacillin-tazobactam or ticarcillin-clavulanate than with the cephalosporin-containing regimens. PMID- 9371377 TI - Characterization of blaTEM-3 and blaSHV-4 beta-lactamase-encoding genes in Citrobacter diversus. PMID- 9371378 TI - Additional characteristics of Bacteroides fragilis carbapenemases belonging to group 3a. PMID- 9371379 TI - Monotherapy versus beta-lactam-aminoglycoside combination therapy for gram negative bacteremia. PMID- 9371380 TI - Childhood cancer etiology: recent reports. PMID- 9371381 TI - Brain tumors and artificial sweeteners? A lesson on not getting soured on epidemiology. PMID- 9371382 TI - Phase II study of cisplatinum and carboplatinum (CACIS) combination in advanced stage neuroblastomas. AB - BACKGROUND: Platinum derivatives are, among others (cyclophosphamide, etoposide, doxorubicin), the most active drugs in neuroblastomas. As the combination of carboplatin (CBDCA) with cisplatinum (CDDP) was proven effective in some carcinomas, we proposed it as a second-line therapy in neuroblastoma. PROCEDURE: Nineteen children with neuroblastoma and primary refractory disease (seven cases) or relapse either untreated (eight cases) or resistant to second-line therapy (four cases), were treated with cisplatinum and carboplatinum (CACIS) combination. All but one patient had previously received CDDP (median 400: 200 to 1,200 mg/m2) and 15 out of 19 had also received CBDCA (median 1,600:800 to 5,000 mg/m2). Twelve had previously received intensification with megatherapy. The CACIS regimen included CBDCA (100 mg/m2/day as a 1-hour infusion, for 4 days) and simultaneous CDDP (25 mg/m2/day as a 3-hour infusion, for 4 days). RESULTS: Eight out of 19 patients (42%) achieved a partial response with a duration of response of 3 to 12 months (median 6). No patient achieved a complete response. The toxicity was mainly hematological, though one patient died after two courses of an interstitial pneumonia of unknown origin. Only one patient developed alopecia. The renal toxicity was low. CONCLUSIONS: The CACIS regimen is an effective combination of platinum derivatives. It may be proposed as second line protocol, especially for children with neuroblastoma who relapse after megatherapy. PMID- 9371383 TI - Effect of steroid and high-dose immunoglobulin therapy on opsoclonus-myoclonus syndrome occurring in neuroblastoma. AB - The authors describe a case of an 8-month-old boy with opsoclonus-myoclonus syndrome (OMS) and coincident unresectable neuroblastoma (NB). He achieved a complete remission for NB after 6 courses of standard-dose chemotherapy without significant neurological improvement despite the use of steroids and high-dose immunoglobulin (HIG), administered separately. Only the combined treatment withthese two drugs induced a complete disappearance of neurological symptoms. On the basis of this experience, the authors suggest the association of steroids plus HIG for the treatment of OMS in patients not responsive to conventional first line therapy with steroids. PMID- 9371384 TI - Non-Hodgkin lymphoma (NHL) as a second neoplasm occurring after neuroblastoma treatment. AB - As far as we know, this is the first report of a non-Hodgkin lymphoma developing after successful treatment of neuroblastoma. A boy was found to have a mediastinal T-cell lymphoma at the age of 5. He had been treated for a neuroblastoma of the left adrenal region 4 years before, when by intensive chemotherapy and radiation a complete remission of the primary tumor was achieved. The second malignancy has also been controlled without evidence of recurrence 1 year after termination of treatment. We conclude that treatment of a neuroblastoma by cytostatic drugs and radiation may lead to a non-Hodgkin lymphoma as a second malignancy. PMID- 9371385 TI - Dental abnormalities in children treated for neuroblastoma. AB - PURPOSE: To determine the frequency and types of dental abnormalities among children treated at a young age for cancer, as represented by neuroblastoma. PATIENTS AND METHODS: We retrospectively reviewed the dental records and panoramic radiographs of 542 children who were treated for neuroblastoma at our institution over a 31-year period. Patients in our study had to meet the following criteria: they were treated on an institutional protocol, they had undergone panoramic radiography, and their dental follow-up continued for at least 2 years after diagnosis. We evaluated the frequency of clinically or radiographically apparent microdontia, excessive caries, root stunting, hypodontia, and enamel hypoplasia in our study population. RESULTS: Of the 52 patients who met the study criteria, 71% developed dental abnormalities, comprising microdontia in 38%, excessive caries in 29%, root stunting in 17%, hypodontia in 17%, and enamel hypoplasia in 17%. In nearly half (23) of our patients, neuroblastoma was diagnosed on or before their first birthday. CONCLUSION: Children treated for neuroblastoma are at high risk for abnormal dental development. The abnormalities in these patients may require extensive dental care and can compromise their quality of life. Frequent dental examinations and an intense oral hygiene program before, during, and after treatment may improve overall dental health. PMID- 9371387 TI - High-dose rate intraoperative radiation therapy for pediatric solid tumors. AB - BACKGROUND: Sixteen pediatric patients with solid tumors received treatment on a protocol designed to test the feasibility and safety of high-dose rate intraoperative radiation therapy (IOHDR) via a remote afterloader. PATIENTS AND METHODS: Patients with Ewing's sarcoma (n = 5), rhabdomyosarcoma (n = 3), synovial cell sarcoma (n = 2), Wilms tumor (n = 2), osteosarcoma, immature teratoma, desmoplastic small round cell tumor, and inflammatory fibrosclerosis were included. IOHDR was used in the initial management of nine patients and at the time of recurrence in seven. Indications for treatment included gross residual disease in 5 and suspected microscopic disease in 11. The general sites treated were the abdomen (n = 3), chest-wall/thoracic cavity (n = 7), and pelvis (n = 6). All of the patients received multiagent chemotherapy prior to the IOHDR procedure, and 5 had been previously treated with external beam radiation therapy. Separate from the procedure during which IORT was performed, 9 patients underwent an attempt at resection at the time of their initial presentation. A dose of 1200 cGy was prescribed to a depth of 0.5 cm from the surface of a multichannel tissue-equivalent applicator. Complications ascribed to IOHDR included an abscess, delayed wound healing, and cytopenia. Four patients received supplemental external beam radiation therapy to the IOHDR site. At the time of IOHDR, 3 patients had disseminated disease within the pleural cavity and one had pulmonary metastases. RESULTS: With a median follow-up of 18 months, the actuarial rates of local control, metastasis-free, and overall survival at 2 years were 61%, 51%, and 54%, respectively. The patterns of failure were local (n = 1), distant (n = 1), and local + distant (n = 1). Two patients are alive with active disease. Nine are alive with no evidence of disease and the remaining 5 are dead from disease (n = 2), other causes (n = 1), or treatment (n = 2). CONCLUSIONS: The potential to improve local control with high doses of radiation should be balanced against the risk of late effects. The ability to confine the dose of radiation to the primary site and decrease the dose to normal tissues makes IOHDR an important adjunct to external beam radiation therapy. IOHDR can be a safe and integral component in the management of pediatric solid tumors. PMID- 9371386 TI - Carboplatin and etoposide with hyperfractionated radiotherapy in children with newly diagnosed diffuse pontine gliomas: a phase I/II study. AB - BACKGROUND: Diffuse pontine gliomas remain one of the most lethal of pediatric malignancies despite the use of increasingly intensive therapies. We delivered intensive chemotherapy during and following 70.2 Gy of hyperfractionated radiation therapy in an attempt to improve survival. PROCEDURE: Nine consecutive children with diffuse pontine gliomas were treated on this single arm study. Carboplatin, given in combination with fixed dose etoposide, was escalated in successive cohorts to determine its maximum tolerated systemic exposure (AUC). Outcome was coded based on imaging characteristics and clinical status. RESULTS: Eight of the nine children on this study died of their disease at a median of 44 weeks, essentially the same survival as those treated on a previous Pediatric Oncology Group study using hyperfractionated radiation therapy alone. Toxicity was almost exclusively hematologic and not associated with significant morbidity. CONCLUSIONS: The use of concurrent carboplatin and etoposide with hyperfractionated radiation therapy did not appear to improve the survival in this group of children with diffuse pontine gliomas. The toxicity of this chemotherapy during radiation therapy was primarily hematologic and well tolerated. New approaches to the treatment of these tumors need to be investigated. PMID- 9371388 TI - CD4+ T-lymphocytopenia in long-term survivors following intensive chemotherapy in childhood cancers. AB - BACKGROUND: It is generally believed the effects of short intensive courses of therapy are rapidly reversible in childhood cancers, and immunologic function following years of maintenance treatment with chemotherapy usually returns to normal by 6 months or less when treatment is terminated. However, we previously demonstrated that dysregulation of immunoglobulins, especially IgD, was observed in long-term survivors following intensive chemotherapy in cancer patients. With regard to cellular immunity, investigators reported that antineoplastic chemotherapy significantly reduces the number of CD4+ T-lymphocytes, and production of newly developing CD4+ T-lymphocytes was inversely related to the patients' age. However, the incidence of CD4+ lymphocytopenia in long-term survivors of childhood cancers is not known. PROCEDURE: Here, we report the flow cytometric analysis of peripheral blood from long-term survivors who continue complete remission off chemotherapy for more than 5 years. RESULTS: Six out of 74 long-term survivors (8.1%), showed low CD4+ T-lymphocyte count (<300/mm3). Three of six patients showed continued CD4+ T-lymphocytopenia over a year. In spite of the persistent low levels of CD4+ T cells, these three patients were not susceptible to severe infections. COMMENT: Intriguingly, in patients with CD4+ T lymphocytopenia there has been a tendency toward increased numbers of natural killer cells or gamma delta T cells that may be operating as a thymus-independent compensatory mechanism to defend the hosts. PMID- 9371389 TI - Favorable outcome after 1-year treatment of childhood T-cell lymphoma/T-cell acute lymphoblastic leukemia. AB - BACKGROUND: For T-malignancies in children a poor prognosis is reported. In these malignancies a combination of lymphoma and leukemia is commonly seen at presentation and most patients are treated according to protocols for acute lymphoblastic leukemia (ALL). These protocols are often designed for the majority of ALL cases, i.e., progenitor-B-ALL. In pediatric lymphoblastic non-Hodgkin's lymphoma without bone marrow infiltration various protocols have been used. The most frequently reported regimens show variable survival rates between 40 and 75%. PATIENTS AND METHODS: From 1989 we have treated 32 consecutive patients with T-cell malignancies, irrespective of localization, with a protocol consisting of a 4-agent induction treatment followed by high doses of methotrexate, and cytosine-arabinoside and intensified bleomycin, adriamycin, cyclophosphamide, vin cristin, prednisone (BACOP) courses. Treatment duration for each patient was 1 year. Twenty-one of the 32 patients had stage IV disease. Follow-up ranged from 1.6 to 7.6 years (median 4.2 years). RESULTS: Overall event-free survival (EFS) was 72%, while in those with stage IV disease it was 67%. No therapy-related deaths occurred. Neither stage, initial leukocyte value, mediastinal involvement, bone marrow involvement, nor the presence of CD1, CD3, CD4, CD8, or CD10 epitopes was prognostically significant. Evaluation of toxicity revealed a minimal decrease of carbon monoxide diffusion and cardiac shortening fraction. CONCLUSION: A relatively short but intensive chemotherapy can be used in T-cell malignancies. The EFS is satisfying, but larger studies are needed. PMID- 9371390 TI - Evaluation of follow-up investigations in osteosarcoma patients: suggestions for an effective follow-up program. AB - BACKGROUND AND PROCEDURE: Follow-up programs for cancer patients aim at improving the overall prognosis by early detection of relapse. In this study, follow-up data from 72 osteosarcoma patients were received in order to determine the value of clinical examination (CE), lung CT-scan (CTL), chest X-ray (CXR), local X-ray (LXR), and bone scintigraphy (BS) in the detection of tumor recurrence. PROCEDURE: Twenty-eight of 72 osteosarcoma patients presented with a total of 61 relapse sites. A continuous remission after relapse treatment could be achieved in 2/16 patients with first lung metastases, in 2/6 patients with local relapse, and in 3/19 patients with more than one lung metastasis. More than 90% of all relapses occurred within 3 years off primary therapy, respectively, within 3 years after detection of relapse. Local relapse and lung metastases were primarily diagnosed by CXR, CTL and CE. BS was the most important investigation to detect distant metastases. No relapse was found by routine X-ray of the primary tumor site. CONCLUSIONS: To improve efficacy of follow-up programs and to reduce radiation load of nonrelapsed patients, the prognosis of patients with lung metastases or local recurrences and the time of high risk for a relapse should be taken into consideration. Since the number of patients who benefit from relapse therapy is still low, it remains to be shown whether an increased frequency of lung CT-scans or MRIs of the primary tumor site will improve early detection of relapse; and if so, whether that will enhance the chance for successful relapse treatment. CXR, CTL and CE should be performed routinely for at least 3 years after completion of therapy or relapse diagnosis. In contrast, BS and LXR appear not to be useful as routine investigations. PMID- 9371391 TI - Outcome of patients with a history of bilateral retinoblastoma treated for a second malignancy: the Memorial Sloan-Kettering experience. AB - BACKGROUND: Patients with bilateral retinoblastoma are well recognized to have a high risk of developing a second malignancy, but there are little published data regarding the outcome of these patients following treatment. PATIENTS AND METHODS: We identified 15 patients with a history of bilateral retinoblastoma who received treatment at Memorial Sloan-Kettering Cancer Center for a newly diagnosed second malignancy. The median age of second tumor occurrence was 18 years (range 10-32 years). Three patients later had a third tumor (18 tumors total). Tumor sites included facial structures in 14 cases and extremities in 4. Histologies included osteosarcoma (5), leiomyosarcoma (5), high-grade spindle cell sarcoma (3), malignant fibrous histiocytoma (3), malignant mesenchymoma (1), and angiosarcoma (1). RESULTS: Nine patients are alive: 7 disease free at a median of 29 months (range 6-214 months) and 2 with residual disease 59 and 148 months post-diagnosis of the second malignancy. Six patients have died at a median of 31 months (range 16-98 months) after diagnosis of the second malignancy. CONCLUSIONS: Patients with a history of bilateral retinoblastoma who develop a second malignancy may enjoy extended periods of survival. Aggressive therapy appropriate to the tumor histology and site is indicated. PMID- 9371392 TI - Survival with combined modality therapy after intracerebral recurrence of pleuropulmonary blastoma. AB - BACKGROUND: We present and discuss the successful treatment of pleuropulmonary blastoma metastatic to the brain using a multimodality regimen with surgery, high dose chemotherapy and radiation therapy. PROCEDURE: A 3-year-old boy referred to our institution with bilateral pulmonary cysts was diagnosed with pleuropulmonary blastoma (PPB). Initial treatment included surgery and multiagent chemotherapy with vincristine, dactinomycin, cyclophosphamide, cisplatin, and doxorubicin. One year after the completion of therapy, his PPB recurred as an intracerebral metastasis, and required further treatment with a multimodality salvage regimen. The child was successfully treated with a subtotal surgical resection, followed by high-dose cyclophosphamide, and radiation therapy. He is now disease-free 24 months later. RESULTS: Intracerebral metastases of PPB have been a uniformly fatal complication of this tumor. Postsurgical chemotherapy and radiation therapy appear to have contributed to the prolonged survival and potential for cure in our patient. CONCLUSIONS: The use of this multimodality regimen may be warranted in other patients with recurrent PPB metastatic to the brain. PMID- 9371393 TI - Poland's syndrome and Wilms tumor: an unusual association. AB - Poland's syndrome, a rare congenital disorder with pectoralis muscular girdle defect, have been reported in association with lymphoreticular malignancies in the past. Childhood solid tumors in association with this congenital anomaly have not been reported so far. We describe this rare association of Poland's syndrome and Wilms tumor. Due to the possibility of increased risk of leukemogenesis in patients with Poland's syndrome, chemo-radiation therapy of Wilms tumor in our patient may increase the risk of secondary leukemia. Therapeutic modification of primary cancer in these patients may be necessary with careful long-term follow up for early detection and treatment of secondary cancer. PMID- 9371394 TI - Acute promyelocytic leukemia (APL) with an unusual cytogenetic presentation. PMID- 9371396 TI - Report of the fourth International Workshop in Human Chromosome 12 Mapping, 1997. PMID- 9371395 TI - "Indwelling central venous catheter-related sepsis". PMID- 9371397 TI - Monosomy 6 in human cultured fibroblast-like cells after long-term stimulation with acidic fibroblast growth factor (FGF1). AB - Long-term exposure to fibroblast growth factor type 1 (FGF1) of fibroblast-like cells derived from neurofibromas of patients with neurofibromatosis type 1, from angiofibromas of patients with tuberous sclerosis, and from foreskin of unaffected donors resulted in the outgrowth of monosomy 6 in 7 out of 14 cell lines examined. After their initial detection by cytogenetic analysis, the proportion of cells which had lost one chromosome 6 was monitored by FISH using a satellite probes specific for chromosome 6 and 7, and by PCR analysis of polymorphic microsatellite markers. Monosomy 6 exceeding baseline levels developed only in cultures exposed to FGF 1, and the emergence of monosomic cells could not be correlated with a given donor's genotype. During serial culture, the proportion of monosomic cells increased to over 90% in 5 of the 7 affected strains. A conspicuous change of cellular morphology from spindle-shaped to more epithelial-type cells was noted in monosomic cultures, even though none of them converted to a permanent cell line during the observation period. We conclude that long-term exposure of human fibroblast-like cell strains to FGF1 results in the emergence of monosomy 6 in 50% of the cultures so treated. A selective advantage for such monosomic cells is the most likely explanation for their steady increase during serial culture. PMID- 9371398 TI - Assignment of synaptonemal complex protein 1 (SCP1) to human chromosome 1p13 by fluorescence in situ hybridization and its expression in the testis. PMID- 9371399 TI - Assignment of the human 14-3-3 epsilon isoform (YWHAE) to human chromosome 17p13 by in situ hybridization. PMID- 9371400 TI - cDNA cloning, characterization, and chromosome mapping of UBE2E2 encoding a human ubiquitin-conjugating E2 enzyme. AB - A cDNA encoding a human ubiquitin-conjugating enzyme (E2) with N-terminal extension (UBE2E2/UbcH8) was isolated. Amino acid sequence within the UBC domain of UBE2E2 shares over 90% identity with human UbcH6, mouse UbcM2, and Drosophila UbcD2, whereas the N-terminal region shows little amino acid sequence similarity with known proteins. The UBE2E2 gene is transcribed in various tissues as a 1.9 kb transcript. The UBE2E2 protein formed a thioester bond with ubiquitin in an E1 dependent manner, indicating that the gene product is a functional E2 enzyme. The UBE2E2 gene was assigned to human chromosome 3p24.2 by fluorescence in situ hybridization. PMID- 9371401 TI - Fluorescence in situ hybridization with a synthetic (T2AG3)n polynucleotide detects several intrachromosomal telomere-like repeats on human chromosomes. AB - (T2AG3) repeats comprise the telomeres of human chromosomes and also are present at interstitial locations. Using a long synthetic (T2AG3)n probe, we have localized telomere-like repeats at several internal sites on human chromosomes. PMID- 9371402 TI - Paternal age effect of YY aneuploidy in human sperm, as assessed by fluorescence in situ hybridization. AB - Sperm samples were collected from 18 healthy men of various ages. Multicolor FISH was performed on each sample, using probes for the sex chromosomes and chromosome 1. A minimum of 10,000 sperm per donor was analyzed. The Pearson correlation coefficient was used to determine if there was an association between donor age and disomy frequency for the sex chromosomes. PMID- 9371403 TI - Analysis of human sperm karyotypes in testicular cancer patients before and after chemotherapy. AB - Sperm karyotype analysis was performed on testicular cancer patients before and after treatment with BEP (bleomycin, etoposide, and cisplatin). A total of 788 sperm chromosome complements was studied, 236 before chemotherapy (CT) and 552 post-CT. There was no significant difference in the total frequency of sperm chromosomal abnormalities pre-CT (10.2%) compared to post-CT (10.7%). Similarly, there were no significant differences in the frequencies of numerical abnormalities (2.5% pre-CT vs. 2.4% post-CT) or structural abnormalities (6.4% pre-CT vs. 7.4% post-CT). The percentage of X-bearing sperm was also not significantly different before (46.3%) and after CT (50.1%). The results in cancer patients were not significantly different from those in control donors. This study corroborates results from our previous analysis of these same men using multicolor fluorescence in situ hybridization for assessment of aneuploidy for chromosomes 1, 12, X, Y, and XY. Together, these two studies suggest that the sperm of men receiving BEP chemotherapy are not at increased risk of chromosomal abnormalities two or more years after treatment. PMID- 9371404 TI - Generation of chicken Z-chromosome painting probes by microdissection for screening large-insert genomic libraries. AB - A strategy for rapid generation of chicken sex chromosome-Z painting probes has been developed using microdissection. Whole chromosome painting probes (WCPs) were prepared from 10-15 copies of mitotic metaphase chicken Z chromosomes. The microisolated chromosomes were subjected to PEG/proteinase K treatment in a collection drop to release DNA, which was then amplified using a degenerate oligonucleotide-primed shuttle PCR (DOP-Shuttle-PCR) strategy. Size distributions of the PCR products were analyzed by agarose gel electrophoresis and smears of DNA were revealed that ranged in size from 200-800 bp, without any evidence of preferential amplification. Both specificity and complexity of the probes have been analyzed by Southern blot and fluorescence in situ hybridization (FISH). Non specific hybridization was efficiently blocked by using chicken competitor DNA. Analysis of the WCPs produced shows that collectively they provide uniform hybridization signals along the entire length of the chicken Z chromosome. To demonstrate one possible application of these complex probes, we screened a large insert bacterial artificial chromosome (BAC) chicken genomic library to select Z chromosome-specific clones. To address specificity of the selected clones and to physically map them to the Z chromosome, FISH analysis was used. Of the 3 clones initially tested, one clone (C3) carrying a 250-kb insert mapped to the distal portion of the short arm of the chicken Z chromosome. Therefore, this technique has provided appropriate probes for screening large-insert genomic libraries. Further application of these probes includes the analysis of chromosome rearrangements, studies of cases of heteroploidy involving the Z chromosome, positional cloning of Z-linked genes and studies on mechanisms of sex-chromosome evolution in birds. PMID- 9371405 TI - Assignment of the "spot 14" gene (THRSP) to human chromosome band 11q13.5 by in situ hybridization. PMID- 9371406 TI - Assignment of 5-hydroxytryptamine receptor (HTR4) to human chromosome 5 bands q31 ->q33 by in situ hybridization. PMID- 9371407 TI - Assignment of the feline c-myc gene (MYC) to cat chromosome F2q21.2 by fluorescence in situ hybridization. PMID- 9371408 TI - Mapping of the Olf89 and Rfp genes to the rat genome: comparison with the mouse and human and new insights into the evolution of the rodent genome. AB - The Rfp (ret finger protein) and Olf89 (olfactory receptor 89) genes were assigned to rat chromosomes 17 and 20, respectively. These two genes are syntenic in human (RFP and OLF89) as they both map to chromosome 6, less than 300 kb apart. The mouse homologs are located on two different chromosomes, namely 13 and 17, respectively. It was shown that these two genes delineate the UA/UB break point, and that this chromosome break occurred in the rodent lineage, before the mouse radiation. Our data indicate that this break occurred before the rat/mouse split, therefore before the Murinae radiation. PMID- 9371409 TI - Fine mapping of the hereditary sensory neuropathy type I locus on chromosome 9q22.1-->q22.3: exclusion of GAS1 and XPA. AB - The peripheral neuropathy, hereditary sensory neuropathy type I (HSN-I) is an autosomal dominant degenerative disorder of sensory and motor neurons. The disease leads to distal sensory loss, distal muscle wasting and weakness, and variable neural deafness. The HSN-I locus was recently mapped to a large genetic interval on chromosome 9q22 that includes the candidate genes GAS1 and XPA. XPA mutations have been shown to cause peripheral neuropathy, and GAS1 is related to the PMP22 gene, which is critical in the pathogenesis of two other peripheral neuropathies. By undertaking extensive genetic linkage analysis within the candidate region, we have refined the HSN-I locus to a critical interval of 3-4 cM. GAS1, XPA, and several other genes that map within the interval initially identified for the disease locus have been investigated and excluded from playing a pathogenic role in HSN-I. PMID- 9371410 TI - Assignment of the tenascin-R gene (Tnr) to mouse chromosome 4 band E2 by fluorescence in situ hybridization; refinement of the human TNR location to chromosome 1q24. PMID- 9371411 TI - Chromosome painting: a method for testing chromosomal changes in lemur evolution. AB - Chromosome painting using commercially available human chromosome-specific DNA libraries was performed to elucidate chromosomal rearrangements in lemur evolution. Human-specific probes for chromosomes 3, 14, 15, and 21 were used to paint chromosomes of six species: Eulemur fulvus mayottensis, Varecia variegata, Lemur catta, Hapalemur simus, H. griseus griseus, and H. aureus. All human chromosome libraries hybridized specifically to chromosome segments of varying length or to whole arms of Lemur chromosomes. The labeling was clearly visualized and permitted precise delineation of the hybridized Lemur chromosomal segments. The use of commercial probes of human chromosomes for chromosome painting appears efficient enough to investigate homology in different species of Lemur. In general, the results obtained by chromosome painting in this study confirm results previously obtained by the R-banding technique but modify the location of some chromosomal rearrangements on different branches of the evolutionary tree of the Lemuridae and reveal some new rearrangements that were not detectable with banding techniques. These results show that chromosome painting with human chromosome-specific DNA libraries can provide useful information in comparative studies on karyotypes of distantly related mammalian species, providing a powerful tool for evolutionary studies, especially in phylogeny. PMID- 9371412 TI - Membrane stretch activates a potassium channel in pig articular chondrocytes. AB - Activity of stretch-activated potassium channels has been recorded in articular chondrocytes using patch-clamp technique. Pressure dependence is described by a sigmoidal function with a half-maximum effect at -20.5 mbar. Selectivity for potassium is demonstrated by agreement between the reversal potential measured at different [K+]o and the prediction of Nernst equation and by block of these channels by caesium. PMID- 9371413 TI - Electrostatic parameters of cationic liposomes commonly used for gene delivery as determined by 4-heptadecyl-7-hydroxycoumarin. AB - Cationic liposomes are used to deliver genes into cells in vitro and in vivo. The present study is aimed to characterize the electrostatic parameters of cationic, large unilamellar vesicles, 110 +/- 20 nm in size, composed of DOTAP/DOPE (mole ratio 1/1), DOTAP/DOPC (mole ratio 1/1), 100% DOTAP, DMRIE/DOPE 1/1, or DC CHOL/DOPE (mole ratio 1/1). { ABBREVIATIONS: DOTAP, N-(1-(2,3-dioleoyloxy)propyl) N,N,N-trimethylammonium chloride; DOPE, 1,2-dioleoyl-sn-glycero-3 phosphatidylethanolamine; DOPC, 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine; DMRIE, 1,2-dimyristyloxypropyl-3-dimethyl-hydroxyethylammonium bromide; DC-CHOL, 3beta[N-(N',N'-dimethylaminoethane)carbamoyl]cholesterol}. The cationic liposomes had a large positive surface potential and a high pH at the liposomal surface in 20 mM Hepes buffer (pH 7.4) as monitored by the pH-sensitive fluorophore 4 heptadecyl-7-hydroxycoumarin. In contrast to DOTAP and DMRIE which were 100% charged, DC-CHOL in DC-CHOL/DOPE (1/1) liposomes was only about 50% charged in 20 mM Hepes buffer (pH 7.4). This might result in an easier dissociation of bilayers containing DC-CHOL from the plasmid DNA (which is necessary to enable transcription), in a decrease of the charge on the external surfaces of the liposomes or DNA-lipid complexes, and in an increase in release of the DNA-lipid complex into the cytosol from the endosomes. Other electrostatic characteristics found were that the primary amine group of DOPE in cationic liposomes dissociated at high (> 7.9) pHbulk and that a salt bridge was likely between the quaternary amine of DOTAP or DMRIE and the phosphate group of DOPE or DOPC, but not between the tertiary amine of DC-CHOL and the phosphate group of DOPE. The liposomes containing DOTAP were unstable upon dilution, probably due to the high critical aggregation concentration of DOTAP, 7 X 10(-5) M. This might also be a mechanism of the dissociation of bilayers containing DOTAP from the plasmid DNA. PMID- 9371414 TI - Structural characterisation of the natural membrane-bound state of melittin: a fluorescence study of a dansylated analogue. AB - The binding of a dansylated analogue of melittin (DNC-melittin) to natural membranes is described. The cytolytic peptide from honey bee venom melittin was enzymatically labelled in its glutamine-25 with the fluorescent probe monodansylcadaverine using guinea pig liver transglutaminase. The labelled peptide was characterised functionally in cytolytic assays, and spectroscopically by circular dichroism and fluorescence. The behaviour of DNC-melittin was, in all respects, indistinguishable from that of the naturally occurring peptide. We used resonance energy transfer to measure the state of aggregation of melittin on the membrane plane in synthetic and natural lipid bilayers. When bound to erythrocyte ghost membranes, the extent of energy transfer was found to be equivalent to when bound to small unilamellar vesicles of phosphatidylcholine. Our results correlate best with a proposed model in which the initial interaction between melittin and the red blood cells could be merely electrostatic and the peptide remains in a low alpha-helical conformation. The next step would be a peptide stabilisation in the membrane in a monomeric alpha-helical conformation that would imply the collapse of the membrane structure and liberation of the cell contents. PMID- 9371415 TI - The construction of a cysteine-less melibiose carrier from E. coli. AB - The melibiose carrier of E. coli is a cation-sugar cotransport system. This membrane protein contains four cysteine residues and the transport function is inhibited by sulfhydryl reagents. In order to investigate the importance of the cysteines, we have constructed a set of four melibiose transporters each of which has one cysteine replaced with serine or valine. The sensitivity of this set of carriers to N-ethylmaleimide was tested and Cys364 was identified as the target of the reagent. In addition, we constructed a melibiose transporter in which all 4 cysteines were replaced with either serine (Cys110, Cys310, and Cys364) or valine (Cys235) and we found that, as expected, the resulting cysteine-less transporter was resistant to the action of N-ethylmaleimide. The cysteine-less melibiose carrier had no significant decrease in ability to accumulate melibiose with cotransported sodium ions or protons. Thus, none of the 4 cysteines are necessary for the function of the melibiose carrier. PMID- 9371417 TI - Kinetics of radiation- and cytochrome c-induced modifications in liposomes analysed by FT-Raman spectroscopy. AB - Fourier transform Raman spectroscopy on artificial lipid membranes was used to study radiation-induced peroxidation processes as a function of time after radiation exposure. The time dependent intensity changes of the Raman lines of various C=C bondings were compared to results obtained by measuring conjugated dienes and by the thiobarbituric acid test for malondialdehydes. The results show that mainly the cis C=C bonds of the lipid chains are involved and, therefore, indicate that gamma-radiation induces conformational changes in the lipid chain while the mobility of the lipid chains is reduced. New Raman bands can be assigned to aldehyde products induced at the end of the peroxidation process. The immediate decrease of the =CH vibration lines was directly correlated with the formation of conjugated C=C double bonds suggesting that these vibration lines are in contrast to the C=C lines solely Raman active, when isolated C=C bonds are present. Cytochrome c (ox.) incorporated into the bilayer of the artificial membranes induced autooxidation processes not influenced by gamma-radiation. It was observed that cytochrome c (ox.)-induced changes of the relative intensity of the C=C bonds differ from those induced by gamma-radiation. These results of cytochrome c together with the inhibitory effects of the antioxidant alpha tocopherol suggest that the radical species involved in the cytochrome c induced process might be different from the free radicals involved in the gamma-radiation induced process. PMID- 9371416 TI - Interaction of a highly potent dimeric enkephalin analog, biphalin, with model membranes. AB - Biphalin, (Tyr-D-Ala-Gly-Phe-NH)2, is a highly potent dimeric analog of enkephalin. Its analgesic efficacy is due in part to its ability to permeate the blood-brain barrier. To aid in understanding the mechanism of the transmembrane movement we determined and analyzed the permeability and partition coefficients of biphalin and a series of analogues where F, Cl, I, NO2, or NH2 were placed in the para position of the aromatic rings of Phe4,4'. Liposomes composed of neutral phospholipids and cholesterol were used as the model membrane. The overall good correlation between permeability and water-membrane partition coefficients suggests that the movement of biphalins across the model membrane is controlled by diffusion and depends on the water-membrane partition coefficient. To explain the observed correlation between permeability and the electron withdrawing/donating character of the substituents in the phenylalanine ring, we examined various folding patterns of Leu-enkephalin, an endogenous pentapeptide that exhibits affinities toward the same classes of opioid receptors (delta and mu). The observed permeabilities and partition coefficients of biphalin and analogues, as well as the tyrosine side chain accessibility, are consistent with the presence of the type of folding where the tyrosine and phenylalanine side chains are in a close contact. We propose that the aromatic ring interaction can promote the peptide permeability by stabilizing a more compact structure of biphalin that would minimize the number of hydrogen bonds with water and therefore enhances partitioning into the model membrane. PMID- 9371418 TI - cis-FFA do not alter membrane depolarization but block Ca2+ influx and GH secretion in KCl-stimulated somatotroph cells. Suggestion for a direct cis-FFA perturbation of the Ca2+ channel opening. AB - It has been reported that cis-unsaturated free fatty acids (cis-FFA) block intracellular Ca2+ rise in EGFR T17 and GH3 cells by perturbing the generation of Ins(1,4,5)P3. In the present work, it was found that cis-FFA did not alter potassium-induced cell depolarization in GH3 cells, while blocking Ca2+ rise and GH secretion. Interestingly enough, saturated or trans-unsaturated FFA exert the opposite actions, i.e., they block cell depolarization without altering Ca2+ rise and hormone secretion. As depolarization activates GH3 cells via direct opening of Ca2+ channels with no generation of intracellular mediators, these results suggest that cis-FFA act by a direct perturbation of the Ca2+ channel opening. PMID- 9371419 TI - Alpha-helical conformation in the C-terminal anchoring domains of E. coli penicillin-binding proteins 4, 5 and 6. AB - The E. coli low molecular mass penicillin-binding proteins (PBP's) are penicillin sensitive, enzymes involved in the terminal stages of peptidoglycan biosynthesesis. These PBP's are believed to anchor to the periplasmic face of the inner membrane via C-terminal amphiphilic alpha-helices but to date the only support for this hypothesis has been obtained from theoretical analysis. In this paper, the conformational behaviour of synthetic peptides corresponding to these C-terminal anchoring domains was studied as a function of solvent, pH, sodium dodecyl sulphate micelles and phospholipid (DOPC, DOPG) vesicles using circular dichroism (CD) spectroscopy. The CD data showed that in 2,2,2-trifluoroethanol or sodium dodecylsulphate, all three peptides have the capacity to form an alpha helical conformation but in aqueous solution or in the presence of phospholipid vesicles only those peptides corresponding to the PBP5 and PBP6 C-termini were observed to do so. A pH dependent loss of alpha-helical conformation in the peptide corresponding to the PBP5 C-terminus was found to correlate with the susceptibility of PBP5 to membrane extraction. This correlation would agree with the hypothesis that an alpha-helical conformation is required for membrane interaction of the PBP5 C-terminal region. PMID- 9371420 TI - Interaction of a synthetic peptide based on the neutrophil-derived antimicrobial protein CAP37 with dipalmitoyl-phosphatidylcholine membranes. AB - CAP37, a cationic antimicrobial protein of Mr 37 kDa is constitutively expressed in human neutrophils. A synthetic peptide, CAP37 P20-44, corresponding to amino acid residues 20 through 44 of the native CAP37 molecule has been shown to mimic the antimicrobial activity of the native protein. An analog of peptide CAP37 P20 44 was synthesized in which the cysteine residues at positions 26 and 42 were replaced with serine residues (CAP37 P20-44Ser). This resulted in a peptide that no longer exhibited bactericidal activity. The effect of different concentrations of the active CAP37 peptide, CAP37 P20-44, and its inactive analog, CAP37 P20 44Ser, on artificial lipid membranes composed of dipalmitoyl phosphatidylcholine (DPPC) was studied using small-angle X-ray scattering and differential scanning calorimetry. The results indicated that CAP37 P20-44 perturbs the periodicity of the lamellar structure as shown by small angle X-ray diffraction, while the effect of the inactive peptide is not as strong. Differential scanning calorimetry further confirms that CAP37 P20-44 interacts with lipid membranes as indicated by increased width of the transition and decreased peak height. Moreover, it completely abolishes the pretransition temperature of the DPPC membranes. The effect of the inactive peptide, CAP37 P20-44Ser on the thermotropic properties of DPPC was small. These studies suggest that CAP37 perturbs the lamellar structure of lipid bilayers and further suggests that the antibiotic action of the molecule may be through its interactions with the lipid components of the Gram negative bacterial membrane. PMID- 9371422 TI - Differential scanning calorimetric studies on the thermotropic phase transitions of dry and hydrated forms of N-acylethanolamines of even chainlengths. AB - N-acylethanolamines (NAEs) have attracted the attention of researchers in the last two decades due to their occurrence in biological membranes under conditions of stress as well as under normal conditions. Differential scanning calorimetric studies have been carried out on dry and hydrated samples of a homologous series of N-acylethanolamines containing saturated acyl chains of even number of carbon atoms (n = 8-20). In both cases a major sharp endothermic transition was observed which occurs at the melting point for the dry NAEs whereas for the hydrated samples it occurs at considerably lower temperatures. The enthalpies and entropies corresponding to this transition could be fitted, in each case, to a straight line suggesting that the transition enthalpy and transition entropy consist of a fixed component from the polar head group and the terminal methyl group, whereas the contribution of the methylene groups, (CH2)n, is linearly proportional to the number of carbon atoms in it. The contributions of each methylene unit to the transition enthalpy and transition entropy of NAEs were found to be deltaH(inc) = 0.82 (+/-0.02) and 0.96 (+/-0.06) kcal mol(-1), and deltaS(inc) = 2.01 (+/- 0.06) and 2.37 (+/-0.17) cal mol(-1) K(-1), respectively, for the dry and hydrated samples of NAEs, whereas the end contributions arising from the head group and the terminal methyl group were determined to be deltaH(o) = -0.10 (+/-0.26) and -0.52 (+/-0.82) kcal mol(-1) and deltaS(o) = 2.12 (+/-0.71) and 3.1 (+/-2.3) cal mol(-1) K(-1), respectively, for the dry and hydrated samples of NAEs. These results are relevant to an understanding of the thermodynamics of the phase properties of NAEs in membranes. PMID- 9371421 TI - pH sensitivity and plasma stability of liposomes containing N-stearoylcysteamine. AB - In this study, we investigated the pH sensitivity of different liposomal formulations containing 10 mol% N-stearoylcysteamine, as pH sensitive molecule. Liposome stability was monitored by determining the release of different entrapped water soluble molecules, 5,6-carboxyfluorescein (CF) being the marker of leakage mainly used. Small unilamellar vesicles composed of egg phosphatidylcholine (EPC) and N-stearoylcysteamine (9:1 molar ratio) incubated at 20 degrees C in citrate phosphate buffer released, at pH 6.8, 2.5 fold the amount of CF released at pH 7.4. The addition of plasma to the incubation medium and an increase of temperature to 37 degrees C led to significantly increased the CF release from EPC/N-stearoylcysteamine SUV, both at pH 7.4 and 6.8. The addition of cholesterol had a stabilizing effect on liposomal vesicles with respect to both temperature and plasma, without affecting pH sensitivity. In fact, at 37 degrees C and in 25% plasma the ternary mixture showed the highest CF release, as a consequence of the moderate acidification of the medium from 7.4 to 6.8. Thus, these liposome formulations are potentially a useful tool for specific drug delivery to pathological tissues such as tumours, inflammation sites and ischemic areas where it is known that a lowering of the pH can occur. PMID- 9371423 TI - Reconstitution of beef heart mitochondrial F0F1 in reverse phase evaporation vesicles. AB - Beef heart mitochondrial F0F1 was reconstituted in proteoliposomes by a new procedure. MF0F1 was inserted in preformed reverse phase evaporation vesicles of large diameters prepared from asolectin (MF0F1-REV). Reconstitution was mediated by Triton X-100, which was subsequently removed by treatment with Bio-Beads. Parameters which resulted in optimal reconstitution were described. The MF0F1-REV proteoliposomes catalyzed an exchange between Pi and ATP and were capable of proton pumping. Both reactions were inhibited by oligomycin and uncoupler of oxidative phosphorylation. The range of Pi-ATP exchange activity of the proteoliposomes (70-110 nmol min[-1] mg[-1]) compared favorably with activities obtained in vesicles reconstituted by cholate dialysis or cholate dilution. The most important aspect of this method is that, unlike other reconstitution methods, exogenous F1 and other coupling factors are not required to obtain high Pi-ATP exchange activity by MF0F1-REV. This simple and rapid reconstitution procedure should be useful for future studies dealing with functional analysis of MF0F1. PMID- 9371424 TI - In vivo aging of rat skeletal muscle sarcoplasmic reticulum Ca-ATPase. Chemical analysis and quantitative simulation by exposure to low levels of peroxyl radicals. AB - Sarcoplasmic reticulum (SR) Ca-ATPase of young adult (5 months) and aged (28 months) Fischer 344 male rat skeletal muscle was analyzed for posttranslational modifications as a result of biological aging and their potential functional consequences. The significant differences in the amino acid composition were a 6.8% lower content of sulfhydryl groups and a ca. 4% lower content of Arg residues of the Ca-ATPase from old as compared to young rats. Based on a total of 24 Cys residues the difference in protein thiols corresponds to a loss of 1.5 mol Cys/mol Ca-ATPase as a result of in vivo aging. The loss of Cys residues was not accompanied by a loss of enzyme activity though the 'aged' Ca-ATPase was more sensitive to heat inactivation, aggregation, and tryptic digestion. A comparison of the total sulfhydryl content of all SR proteins present revealed a 13% lower amount for SR vesicles isolated from aged rats. Compared to the alterations of Cys and Arg, there was only a slight and probably physiologically insignificant increase of protein carbonyls with aging, i.e. from 0.32 to 0.46 mol carbonyl groups per mol of Ca-ATPase. When SR vesicles from young rats were exposed to AAPH-derived peroxyl radicals, there was a loss of ca. 1.38 x 10(-4) M total SR sulfhydryl groups per 4 mg SR protein/ml (corresponding to ca. 25%) and a loss of 9.6 x 10(-5) M Ca-ATPase sulfhydryl groups (corresponding to ca. 31%) per 1.6 x 10(-5) M initiating peroxyl radicals, indicating that the stoichiometry of sulfhydryl oxidation was > or = 6 oxidized thiols per initiating AAPH-derived peroxyl radical. Besides Cys, the exposure to AAPH-derived radicals caused a slight loss of Ca-ATPase Arg, Met, and Ser residues. Most importantly, the SR Ca ATPase exposed to this low concentration of peroxyl radicals displayed physical and functional properties quantitatively comparable to those of SR Ca-ATPase isolated from aged rats, i.e. no immediate loss of activity, increased susceptibility to heat inactivation, aggregation, and tryptic digestion. Moreover, a comparison of kinetically early tryptic fragments by HPLC electrospray MS and N-terminal sequencing revealed that similar peptide fragments were produced from 'aged' and AAPH-oxidized Ca-ATPase which were not (or kinetically significantly later) generated from the 'young' Ca-ATPase, suggesting some conformational changes of the Ca-ATPase as a result of aging and AAPH exposure. All except one of these peptides originated from locations remote from the nucleotide-binding and calcium-binding sites. The latter results suggest that aging and AAPH-exposure may target similar Cys residues, mainly at locations remote from the nucleotide-binding and calcium-binding sites, rationalizing the fact that Cys oxidation did not immediately cause inactivation of the Ca-ATPase. Our results provide a quantitative estimate of a net concentration of reactive oxygen species, here peroxyl radicals, which induces physical and chemical alterations of the SR Ca-ATPase quantitatively comparable to those induced by in vivo aging. PMID- 9371426 TI - Toxicity and immunomodulatory activity of liposomal vectors formulated with cationic lipids toward immune effector cells. AB - Liposomal vectors formulated with cationic lipids (cationic liposomes) and fusogenic dioleoylphosphatidylethanolamine (DOPE) have potential for modulating the immune system by delivering gene or antisense oligonucleotide inside immune cells. The toxicity and the immunoadjuvant activity of cationic liposomes containing nucleic acids toward immune effector cells has not been investigated in detail. In this report, we have evaluated the toxicity of liposomes formulated with various cationic lipids towards murine macrophages and T lymphocytes and the human monocyte-like U937 cell line. The effect of these cationic liposomes on the synthesis of two immunomodulators produced by activated macrophages, nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha), has also been determined. We have found that liposomes formulated from DOPE and cationic lipids based on diacyltrimethylammonium propane (dioleoyl-, dimyristoyl-, dipalmitoyl-, disteroyl : DOTAP, DMTAP, DPTAP, DSTAP) or dimethyldioctadecylammonium bromide (DDAB) are highly toxic in vitro toward phagocytic cells (macrophages and U937 cells), but not towards non-phagocytic T lymphocytes. The rank order of toxicity was DOPE/DDAB > DOPE/DOTAP > DOPE/DMTAP > DOPE/DPTAP > DOPE/DSTAP. The ED50's for macrophage toxicity were < 10 nmol/ml for DOPE/DDAB, 12 nmol/ml for DOPE/DOTAP, 50 nmol/ml for DOPE/DMTAP, 400 nmol/ml for DOPE/DPTAP and > 1000 nmol/ml for DOPE/DSTAP. The incorporation of DNA (antisense oligonucleotide or plasmid vector) into the cationic liposomes marginally reduced their toxicity towards macrophages. Although toxicity was observed with cationic lipids alone, it was clearly enhanced by the presence of DOPE. The replacement of DOPE by dipalmitoylphosphatidylcholine (DPPC) significantly reduced liposome toxicity towards macrophages, and the presence of dipalmitoylphosphatidylethanolamine PEG2000 (DPPE-PEG2000: 10 mol%) in the liposomes completely abolished this toxicity. Cationic liposomes, irrespective of their DNA content, downregulated NO and TNF-alpha synthesis by lipopolysaccharide (LPS)/interferon-gamma (IFN-gamma) activated macrophages. The replacement of DOPE by DPPC, or the addition of DPPE PEG2000, restored NO and TNF-alpha synthesis by activated macrophages. Since macrophages constitute the major site of liposome localization after parenteral administration and play an important role in the control of the immune system, cationic liposomes should be used with caution to deliver gene or antisense oligonucleotide to mammalian cells. Cationic lipids show in vitro toxicity toward phagocytic cells and inhibit in vitro and in situ NO and TNF-alpha production by activated macrophages. PMID- 9371425 TI - Effect of adenosine on the ouabain-insensitive Na+-ATPase activity from basolateral membrane of the proximal tubule. AB - The regulation of the furosemide-sensitive Na+-ATPase activity and ouabain sensitive (Na+ + K+)ATPase activities from proximal tubules by adenosine was investigated. When the concentration of adenosine was increased the furosemide sensitive ATPase activity decreased with maximal inhibition at 10(-8) M (56% of inhibition). However, the (Na+ + K+)ATPase activity was not affected by adenosine. Theophylline, an antagonist of P1 adenosine receptor, completely reversed the effect of adenosine on the furosemide-sensitive ATPase activity in a dose-response manner. The adenosine effect was mimicked by N6-cyclohexyladenosine (CHA), an agonist for A1 adenosine receptor. 5'-N-ethylcarboxamideadenosine (NECA), an agonist for A2 adenosine receptor, did not affect the furosemide sensitive ATPase activity. When adenosine was used in the presence of 1 microg ml(-1) pertussis toxin, a Gi protein inhibitor, no change in the furosemide sensitive ATPase activity was observed. The addition of 1 nM cholera toxin increased the Na+-ATPase activity by 60%. Adenosine decreased the cholera toxin stimulated Na+-ATPase in 42%, similar to the effect observed in the absence of cholera toxin. Dibutyryl-cAMP reversed the effect of adenosine in a dose dependent manner while the protein kinase A peptide inhibitor mimicked it. These data are compatible with a modulatory effect of adenosine on the Na+-ATPase activity via A1 subtype receptor. PMID- 9371427 TI - Effects on mollicutes (wall-less bacteria) of synthetic peptides comprising a signal peptide or a membrane fusion peptide, and a nuclear localization sequence (NLS) -- a comparison with melittin. AB - In order to investigate the effect of primary amphipathic peptides on mollicutes (wall-less bacteria), we have synthesised five molecules (P1, P2, P3, JM123, and JM133) comprising a 16 to 18-residue hydrophobic sequence and the nuclear localization sequence (NLS) PKKKRKV of simian virus 40 large-T antigen, C terminated by a cysteamide group. The hydrophobic cluster was in P1 the signal sequence of the heavy chain of Caiman crocodilus immunoglobulin G and in JM123 the fusion peptide of human immunodeficiency virus 1 glycoprotein gp41 in which phenylalanine7 was replaced by a tryptophan residue. The homologues P2, P3, and JM133 were obtained by slight alterations of these sequences. Circular dichroism spectroscopy revealed that, in liposomes, P-series peptides were mainly under the form of beta-sheets whereas JM-series peptides displayed a high proportion of turns. These peptides proved to be bactericidal for some mollicutes, notably Acholeplasma laidlawii, but were much less potent than melittin. Furthermore, their antibiotic activity was independent of the average thickness of the plasma membrane hydrophobic core whilst that of melittin was inversely related to the thickness. Melittin and the synthetic peptides abolished spiroplasma cell motility and helicity, but only melittin and P-series peptides split the cells into globular forms displaying an average diameter of ca. 1 microm. In contrast to melittin, the synthetic peptides agglutinated spiroplasmas, suggesting that their polycationic NLS was exposed on the cell surface. P-series peptides decreased, though less efficiently than melittin, A. laidlawii and Spiroplasma melliferum membrane potential (delta psi) and transmembrane pH gradient (delta pH), at concentrations much lower than their minimal inhibitory concentrations whilst JM-series peptides had no effect on delta psi and delta pH in the same conditions. Actually, the bactericidal activity of these peptides towards mollicutes was proportional to their ability to collapse the electrochemical transmembrane potential. PMID- 9371428 TI - Enhancement of the in vivo circulation lifetime of L-alpha distearoylphosphatidylcholine liposomes: importance of liposomal aggregation versus complement opsonization. AB - Incorporation of N-(omega-carboxy)acylamido-phosphatidylethanolamines (-PEs) into large unilamellar vesicles (LUVs) of L-alpha-distearoylphosphatidylcholine (DSPC) was found to dramatically increase the in vivo liposomal circulation lifetime in rats, reaching a maximal effect at 10 mol.% of the total phospholipid. Neither pure DSPC liposomes nor those with the longest circulating derivative, N-glutaryl dipalmitoylphosphatidylethanolamine (-DPPE), were found to significantly bind complement from serum. Therefore, the relatively short circulation time of pure DSPC liposomes did not appear to be related to greater complement opsonization leading to uptake by the reticuloendothelial system. However, N-(omega carboxy)acylamido-PEs were particularly efficient inhibitors of a limited aggregation detected for pure DSPC liposomes. The aggregation tendency of DSPC liposomes incorporating various structural analogs of N-glutaryl-DPPE correlated inversely with the circulation lifetimes. Therefore, it is concluded that such PE derivatives enhance the circulation time by preventing liposomal aggregation and avoiding a poorly understood mechanism of clearance that is dependent on size but is independent of complement opsonization. At high concentrations of N-glutaryl DPPE (above 10 mol.%), the liposomes exhibited strong complement opsonization and were cleared from circulation rapidly, as were other highly negatively charged liposomes. These data demonstrate that both the lack of opsonization and the lack of a tendency to aggregate are required for long circulation. Liposomal disaggregation via N-(omega-carboxy)acylamido-PEs yields a new class of large unilamellar DSPC liposomes with circulation lifetimes that are comparable to those of sterically stabilized liposomes. PMID- 9371429 TI - New functions for the three subunits of the CzcCBA cation-proton antiporter. AB - The membrane-bound CzcCBA protein complex mediates heavy metal resistance in Alcaligenes eutrophus by an active cation efflux mechanism driven by cation proton antiport. The CzcA protein alone is able to mediate weak resistance to zinc and cobalt and is thus the central antiporter subunit. The two histidine rich motifs in the CzcB subunit are not essential for zinc resistance; however, deletion of both motifs led to a small but significant loss of resistance to this cation. Translation of the czcC gene encoding the third subunit of the CzcCBA complex starts earlier than predicted, and CzcC is probably a periplasmic protein, as judged by the appearance of two bands after expression of czcC in Escherichia coli under control of the phage T7 promoter. Fusions of CzcC and CzcB with alkaline phosphatase and beta-galactosidase are in agreement with a periplasmic location of most parts of both proteins. Both CzcC and CzcB are bound to a membrane, probably the outer membrane, by themselves and do not need either CzcA or each other as an anchoring protein. Based on these data, a new working model for the function of the Czc system is discussed. PMID- 9371430 TI - katGI and katGII encode two different catalases-peroxidases in Mycobacterium fortuitum. AB - It has been suggested that catalase-peroxidase plays an important role in several aspects of mycobacterial metabolism and is a virulence factor in the main pathogenic mycobacteria. In this investigation, we studied genes encoding for this protein in the fast-growing opportunistic pathogen Mycobacterium fortuitum. Nucleotide sequences of two different catalase-peroxidase genes (katGI and katGII) of M. fortuitum are described. They show only 64% homology at the nucleotide level and 55% identity at the amino acid level, and they are more similar to catalases-peroxidases from different bacteria, including mycobacteria, than to each other. Both proteins were found to be expressed in actively growing M. fortuitum, and both could also be expressed when transformed into Escherichia coli and M. aurum. We detected the presence of a copy of IS6100 in the neighboring region of a katG gene in the M. fortuitum strain in which this element was identified (strain FC1). The influence of each katG gene on isoniazid (isonicotinic acid hydrazide; INH) susceptibility of mycobacteria was checked by using the INH-sensitive M. aurum as the host. Resistance to INH was induced when katGI was transformed into INH-sensitive M. aurum, suggesting that this enzyme contributes to the natural resistance of M. fortuitum to the drug. This is the first report showing two different genes encoding same enzyme activity which are actively expressed within the same mycobacterial strain. PMID- 9371431 TI - Expression of thiamin biosynthetic genes (thiCOGE) and production of symbiotic terminal oxidase cbb3 in Rhizobium etli. AB - In this paper we report the cloning and sequence analysis of four genes, located on plasmid pb, which are involved in the synthesis of thiamin in Rhizobium etli (thiC, thiO, thiG, and thiE). Two precursors, 4-methyl-5-(beta hydroxyethyl)thiazole monophosphate and 4-amino-5-hydroxymethylpyrimidine pyrophosphate, are coupled to form thiamin monophosphate, which is then phosphorylated to make thiamin pyrophosphate. The first open reading frame (ORF) product, of 610 residues, has significant homology (69% identity) with the product of thiC from Escherichia coli, which is involved in the synthesis of hydroxymethylpyrimidine. The second ORF product, of 327 residues, is the product of a novel gene denoted thiO. A protein motif involved in flavin adenine dinucleotide binding was found in the amino-terminal part of ThiO; also, residues involved in the catalytic site of D-amino acid oxidases are conserved in ThiO, suggesting that it catalyzes the oxidative deamination of some intermediate of thiamin biosynthesis. The third ORF product, of 323 residues, has significant homology (38% identity) with ThiG from E. coli, which is involved in the synthesis of the thiazole. The fourth ORF product, of 204 residues, has significant homology (47% identity) with the product of thiE from E. coli, which is involved in the condensation of hydroxymethylpyrimidine and thiazole. Strain CFN037 is an R. etli mutant induced by a single Tn5mob insertion in the promoter region of the thiCOGE gene cluster. The Tn5mob insertion in CFN037 occurred within a 39-bp region which is highly conserved in all of the thiC promoters analyzed and promotes constitutive expression of thiC. Primer extension analysis showed that thiC transcription in strain CFN037 originates within the Tn5 element. Analysis of c-type protein content and expression of the fixNOQP operon, which codes for the symbiotic terminal oxidase cbb3, revealed that CFN037 produces the cbb3 terminal oxidase. These data show a direct relationship between expression of thiC and production of the cbb3 terminal oxidase. This is consistent with the proposition that a purine-related metabolite, 5 aminoimidazole-4-carboxamide ribonucleotide, is a negative effector of the production of the symbiotic terminal oxidase cbb3 in R. etli. PMID- 9371432 TI - Adaptation to nutrient starvation in Rhizobium leguminosarum bv. phaseoli: analysis of survival, stress resistance, and changes in macromolecular synthesis during entry to and exit from stationary phase. AB - The nitrogen-fixing bacterium Rhizobium leguminosarum bv. phaseoli often has to survive long periods of starvation in the soil, when not in a useful symbiotic relationship with leguminous plants. We report that it can survive carbon, nitrogen, and phosphorus starvation for at least 2 months with little loss of viability. Upon carbon starvation, R. leguminosarum cells were found to undergo reductive cell division. During this period, they acquired the potential for long term starvation-survival, levels of protein, DNA, and RNA synthesis were decreased to base levels, and pool mRNA was stabilized. The starved cells are ready to rapidly restart growth when nutrients become available. Upon addition of fresh nutrients, there is an immediate increase in the levels of macromolecular synthesis, pool mRNA destabilizes, and the cultures enter exponential growth within 5 to 8 h. The starved cells were cross-protected against pH, heat, osmotic, and oxidative shock. These results provide evidence for a general starvation response in R. leguminosarum similar to that previously found in other bacteria such as Escherichia coli and Vibrio sp. PMID- 9371433 TI - Methylthiol:coenzyme M methyltransferase from Methanosarcina barkeri, an enzyme of methanogenesis from dimethylsulfide and methylmercaptopropionate. AB - During growth on acetate, Methanosarcina barkeri expresses catabolic enzymes for other methanogenic substrates such as monomethylamine. The range of substrates used by cells grown on acetate was further explored, and it was found that cells grown on acetate also converted dimethylsulfide (DMS) and methylmercaptopropionate (MMPA) to methane. Cells or extracts of cells grown on trimethylamine or methanol did not utilize either DMS or MMPA. During growth on acetate, cultures demethylated MMPA, producing methane and mercaptopropionate. Extracts of acetate-grown cells possessed DMS- and MMPA-dependent coenzyme M (CoM) methylation activities. The activity peaks of CoM methylation with either DMS or MMPA coeluted upon gel permeation chromatography of extracts of acetate grown cells consistent with an apparent molecular mass of 470 kDa. A 480-kDa corrinoid protein, previously demonstrated to be a CoM methylase but otherwise of unknown physiological function, was found to methylate CoM with either DMS or MMPA. MMPA was demethylated by the purified 480-kDa CoM methylase, consuming 1 mol of CoM and producing 1 mol of mercaptopropionate. DMS was demethylated by the purified protein, consuming 1 mol of CoM and producing 1 mol of methanethiol. The methylthiol:CoM methyltransferase reaction could be initiated only with the enzyme-bound corrinoid in the methylated state. CoM could demethylate, and DMS and MMPA could remethylate, the corrinoid cofactor. The monomethylamine corrinoid protein and the A isozyme of methylcobamide:CoM methyltransferase (proteins homologous to the two subunits comprising the 480-kDa CoM methylase) did not catalyze CoM methylation with methylated thiols. These results indicate that the 480-kDa corrinoid protein functions as a CoM methylase during methanogenesis from DMS or MMPA. PMID- 9371434 TI - Regioselectivity of nitroglycerin denitration by flavoprotein nitroester reductases purified from two Pseudomonas species. AB - Two species of Pseudomonas capable of utilizing nitroglycerin (NG) as a sole nitrogen source were isolated from NG-contaminated soil and identified as Pseudomonas putida II-B and P. fluorescens I-C. While 9 of 13 laboratory bacterial strains that presumably had no previous exposure to NG could degrade low concentrations of NG (0.44 mM), the natural isolates tolerated concentrations of NG that were toxic to the lab strains (1.76 mM and higher). Whole-cell studies revealed that the two natural isolates produced different mixtures of the isomers of dinitroglycerol (DNG) and mononitroglycerol (MNG). A monomeric, flavin mononucleotide-containing NG reductase was purified from each natural isolate. These enzymes catalyzed the NADPH-dependent denitration of NG, yielding nitrite. Apparent kinetic constants were determined for both reductases. The P. putida enzyme had a Km for NG of 52 +/- 4 microM, a Km for NADPH of 28 +/- 2 microM, and a Vmax of 124 +/- 6 microM x min(-1), while the P. fluorescens enzyme had a Km for NG of 110 +/- 10 microM, a Km for NADPH of 5 +/- 1 microM, and a Vmax of 110 +/- 11 microM x min(-1). Anaerobic titration experiments confirmed the stoichiometry of NADPH consumption, changes in flavin oxidation state, and multiple steps of nitrite removal from NG. The products formed during time dependent denitration reactions were consistent with a single enzyme being responsible for the in vivo product distributions. Simulation of the product formation kinetics by numerical integration showed that the P. putida enzyme produced an approximately 2-fold molar excess of 1,2-DNG relative to 1,3-DNG. This result could be fortuitous or could possibly be consistent with a random removal of the first nitro group from either the terminal (C-1 and C-3) positions or middle (C-2) position. However, during the denitration of 1,2-DNG, a 1.3-fold selectivity for the C-1 nitro group was determined. Comparable simulations of the product distributions from the P. fluorescens enzyme showed that NG was denitrated with a 4.6-fold selectivity for the C-2 position. Furthermore, a 2.4 fold selectivity for removal of the nitro group from the C-2 position of 1,2-DNG was also determined. The MNG isomers were not effectively denitrated by either purified enzyme, which suggests a reason why NG could not be used as a sole carbon source by the isolated organisms. PMID- 9371435 TI - Rhizobium meliloti mutants deficient in phospholipid N-methyltransferase still contain phosphatidylcholine. AB - Phosphatidylcholine (PC) is the major membrane-forming phospholipid in eukaryotes. In addition to this structural function, PC is thought to play a major role in lipid turnover and signalling in eukaryotic systems. In prokaryotes, only some groups of bacteria, among them the members of the family Rhizobiaceae, contain PC. To understand the role of PC in bacteria, we have studied Rhizobium meliloti 1021, which is able to form nitrogen-fixing nodules on its legume host plants and therefore has a very complex phenotype. R. meliloti was mutagenized with N-methyl-N'-nitro-N-nitrosoguanidine, and potential mutants defective in phospholipid N-methyltransferase were screened by using a colony autoradiography procedure. Filters carrying lysed replicas of mutagenized colonies were incubated with S-adenosyl-L-[methyl-14C]methionine. Enzymatic transfer of methyl groups to phosphatidylethanolamine (PE) leads to the formation of PC and therefore to the incorporation of radiolabel into lipid material. Screening of 24,000 colonies for reduced incorporation of radiolabel into lipids led to the identification of seven mutants which have a much-reduced specific activity of phospholipid N-methyltransferase. In vivo labelling of mutant lipids with [14C]acetate showed that the methylated PC biosynthesis intermediates phosphatidylmonomethylethanolamine and phosphatidyldimethylethanolamine are no longer detectable. This loss is combined with a corresponding increase in the potential methyl acceptor PE. These results indicate that PC biosynthesis via the methylation pathway is indeed blocked in the mutants isolated. However, mass spectrometric analysis of the lipids shows that PC was still present when the mutants had been grown on complex medium and that it was present in the mutants in wild-type amounts. In vivo labelling with [methyl-14C]methionine shows that in phospholipid N-methyltransferase-deficient mutants, the choline moiety of PC is not formed by methylation. These findings suggest the existence of a second pathway for PC biosynthesis in Rhizobium. PMID- 9371436 TI - Streptothricin biosynthesis is catalyzed by enzymes related to nonribosomal peptide bond formation. AB - In a search for strains producing biocides with a wide spectrum of activity, a new strain was isolated. This strain was taxonomically characterized as Streptomyces rochei F20, and the chemical structure of the bioactive product extracted from its fermentation broth was determined to be a mixture of streptothricins. From a genomic library of the producer strain prepared in the heterologous host Streptomyces lividans, a 7.2-kb DNA fragment which conferred resistance to the antibiotic was isolated. DNA sequencing of 5.2 kb from the cloned fragment revealed five open reading frames (ORFs) such that ORF1, -2, -3, and -4 were transcribed in the same direction while ORF5 was convergently arranged. The deduced product of ORF1 strongly resembled those of genes involved in peptide formation by a nonribosomal mechanism; the ORF2 product strongly resembled that of mphA and mphB isolated from Escherichia coli, which determines resistance to several macrolides by a macrolide 2'-phosphotransferase activity; the ORF3 product had similarities with several hydrolases; and the ORF5 product strongly resembled streptothricin acetyltransferases from different gram-positive and gram-negative bacteria. ORF5 was shown to be responsible for acetyl coenzyme A-dependent streptothricin acetylation. No similarities in the databases for the ORF4 product were found. Unlike other peptide synthases, that for streptothricin biosynthesis was arranged as a multienzymatic system rather than a multifunctional protein. Insertional inactivation of ORF1 and ORF2 (and to a lesser degree, of ORF3) abolishes antibiotic biosynthesis, suggesting their involvement in the streptothricin biosynthetic pathway. PMID- 9371437 TI - Identification and characterization of the two-enzyme system catalyzing oxidation of EDTA in the EDTA-degrading bacterial strain DSM 9103. AB - In a gram-negative isolate (DSM 9103) able to grow with EDTA as the sole source of carbon, nitrogen, and energy, the first two steps of the catabolic pathway for EDTA were elucidated. They consisted of the sequential oxidative removal of two acetyl groups, resulting in the formation of glyoxylate. An enzyme complex that catalyzes the removal of two acetyl groups was purified and characterized. In the reaction, ethylenediaminetriacetate (ED3A) was formed as an intermediate and N,N' ethylenediaminediacetate was the end product. The enzyme complex consisted of two components: component A' (cA'), most likely a monooxygenase, which catalyzes the cleavage of EDTA and ED3A while consuming oxygen and reduced flavin mononucleotide (FMN)-H2, and component B' (cB'), an NADH2:FMN oxidoreductase that provides FMNH2 for cA'. cB' could be replaced by other NADH2:FMN oxidoreductases such as component B of the nitrilotriacetate monooxygenase or the NADH2:FMN oxidoreductase from Photobacterium fischeri. The EDTA-oxidizing enzyme complex accepted EDTA as a substrate only when it was complexed with Mg2+, Zn2+, Mn2+, Co2+, or Cu2+. Moreover, the enzyme complex catalyzed the removal of acetyl groups from several other aminopolycarboxylic acids that possess three or more acetyl groups. PMID- 9371438 TI - Formation of potent hybrid promoters of the mutant llm gene by IS256 transposition in methicillin-resistant Staphylococcus aureus. AB - From high-level methicillin-resistant Staphylococcus aureus SRM551, the low-level heterogeneously resistant mutant, SRM563, was isolated by transposon mutagenesis. The transposon insertion occurred in the 3' region of the llm gene in the mutant (H. Maki, T. Yamaguchi, and K. Murakami, J. Bacteriol. 176:4993-5000, 1994). Resistant revertants were generated from the mutant strain SRM563 on the plate containing methicillin at a concentration of 12.5 microg/ml or more. In some revertants, the insertion sequence IS256 was observed to be transposed into one of five sites localized 88 to 212 bp upstream of the mutant llm at a frequency of 2.8 x 10(-7) in the bacterial population. The IS256 transposition created a new hybrid promoter in which the -35 region at the end of IS256 was properly arranged in relation to the -10-like sequence upstream of llm. The new promoters greatly enhanced the transcription of the mutant llm, as judged by blotting analysis of llm mRNA, with concomitant elevation of the methicillin resistance. Involvement of the insertion sequence in the heteroresistance characteristics of methicillin resistant S. aureus was suggested. PMID- 9371440 TI - Molecular cloning and transcriptional analysis of a guanosine kinase gene of Brevibacterium acetylicum ATCC 953. AB - The Brevibacterium acetylicum gsk gene, which encodes guanosine kinase (ATP:guanosine 5'-phosphotransferase), a kinase that is involved in guanosine salvage pathways, has been cloned by using the N-terminal amino acid sequence of the purified protein. The cloned chromosomal fragment containing the gsk gene was sequenced and shown to encode a polypeptide of 303 amino acids with a molecular mass of 32,536 Da, which is in good agreement with the measured molecular weight of the purified enzyme. Recombinant Escherichia coli strains harboring plasmids carrying the B. acetylicum gsk gene overexpressed both guanosine and inosine kinase activities. The primary structure of the gsk gene shows similarity to amino acid sequences of sugar kinases classified in the ribokinase family stronger than to those of the E. coli gsk gene encoding guanosine kinase and other nucleoside kinases. Northern blot analysis and primer extension analysis revealed a 1.4-kb transcript and promoter sequences, like the E. coli sigma70 and B. subtilis sigmaA consensus sequences, respectively. These results, together with the nucleotide sequence of the downstream region of gsk, suggested that the organization of B. acetylicum gsk is bicistronic. The second gene, orf2, shows significant similarity to the mutT mutator genes of several organisms, although its function has not yet been identified. The gsk gene was specifically transcribed in the early exponential growth phase, which seems to correspond to the specific guanosine kinase activity profile and suggests a role in controlling the nucleoside monophosphate level by efficiently recycling guanosine when cells are in the early exponential phase. PMID- 9371439 TI - Strategies used by pathogenic and nonpathogenic mycobacteria to synthesize rRNA. AB - One rRNA operon of all mycobacteria studied so far is located downstream from a gene thought to code for the enzyme UDP-N-acetylglucosamine carboxyvinyl transferase (UNAcGCT), which is important to cell wall synthesis. This operon has been designated rrnAf for fast-growing mycobacteria and rrnAs for slow growers. We have investigated the upstream sequences and promoter activities of rrnA operons of typical fast growers which also possess a second rrn (rrnBf) operon and of the rrnA operons of the fast growers Mycobacterium abscessus and Mycobacterium chelonae, which each have a single rrn operon per genome. These fast growers have a common strategy for increasing the efficiency of transcription of their rrnA operons, thereby increasing the cells' potential for ribosome synthesis. This strategy involves the use of multiple (three to five) promoters which may have arisen through successive duplication events. Thus we have identified a hypervariable multiple promoter region (HMPR) located between the UNAcGCT gene and the 16S rRNA coding region. Two promoters, P1 and PCL1, appear to play pivotal roles in mycobacterial rRNA synthesis; they are present in all of the species examined and are the only promoters used for rRNA synthesis by the pathogenic slow growers. P1 is located within the coding region of the UNAcGCT gene, and PCL1 has a characteristic sequence that is related to but distinct from that of the additional promoters. In fast-growing species, P1 and PCL1 produce less than 10% of rRNA transcripts, so the additional promoters found in the HMPR are important in increasing the potential for rRNA synthesis during rapid growth. In contrast, rrnB operons appear to be regulated by a single promoter; because less divergence has taken place, rrnB appears to be younger than rrnA. PMID- 9371441 TI - Structure and function of poly(3-hydroxybutyrate) depolymerase from Alcaligenes faecalis T1. AB - Poly(3-hydroxybutyrate) (PHB) depolymerase from Alcaligenes faecalis T1 is composed of three domains: the catalytic (C) domain, the fibronectin type III like (F) domain, and the substrate-binding (S) domain. We constructed domain deletion, inversion, chimera, and extra-F-domain mutants and examined their enzyme activity and PHB-binding ability. In addition, we performed substitution of 214Asp and 273His with glycine and aspartate, respectively, to examine their participation in a catalytic triad together with 139Ser. The mutant with both the F and S domains deleted and the trypsin-digested enzyme showed no PHB-hydrolyzing activity and less PHB-binding ability than that of the wild-type enzyme but retained D-(-)-3-hydroxybutyrate trimer-hydrolyzing activity at a level similar to that of the wild-type enzyme. The mutant with the F domain deleted and the mutant which had the order of the F and S domains inverted retained PHB-binding ability and trimer-hydrolyzing activity at levels similar to those of the wild type enzyme but lost PHB-hydrolyzing activity. The chimera mutant, in which the F domain was substituted with a Thr-rich domain of PHB depolymerase A from Pseudomonas lemoignei, and the extra-F-domain mutant, with an additional F domain, retained trimer- and PHB-hydrolyzing activities and PHB-binding ability at levels similar to those of the wild-type enzyme. Two mutants (D214G and H273D) showed no enzymatic activity toward trimer and PHB, and they were not labeled with [3H]diisopropylfluorophosphate. PMID- 9371442 TI - hetC, a gene coding for a protein similar to bacterial ABC protein exporters, is involved in early regulation of heterocyst differentiation in Anabaena sp. strain PCC 7120. AB - Transposon-generated mutant C3 of Anabaena sp. strain PCC 7120 is unable to form heterocysts upon deprivation of combined nitrogen but forms a pattern of spaced, weakly fluorescent cells after 2 days of deprivation. Sequence analysis of chromosomal DNA adjacent to the ends of transposon Tn5-1058 in mutant C3 showed a 1,044-amino-acid open reading frame, designated hetC, whose predicted protein product throughout its C-terminal two-thirds has extensive similarity to the HlyB family of bacterial protein exporters. Its N-terminal third is unique and does not resemble any known protein. hetC lies 1,165 bp 5' from the previously described gene hetP. Reconstruction of the C3 mutation and its complementation in trans with a wild-type copy of hetC confirmed that hetC has an essential regulatory role early in heterocyst development. hetC is induced ca. 4 h after nitrogen stepdown, hours after induction of hetR. Expression of hetC depends on HetR and may depend on HetC. Highly similar sequences are present 5' from the initiation codons and in the 3' untranslated regions of hetC and of two heterocyst-specific genes, devA and hetP. PMID- 9371443 TI - Betaine and L-carnitine transport by Listeria monocytogenes Scott A in response to osmotic signals. AB - The naturally occurring compatible solutes betaine and L-carnitine allow the food borne pathogen Listeria monocytogenes to adjust to environments of high osmotic strength. Previously, it was demonstrated that L. monocytogenes possesses an ATP dependent L-carnitine transporter (A. Verheul, F. M. Rombouts, R. R. Beumer, and T. Abee, J. Bacteriol. 177:3205-3212, 1995). The present study reveals that betaine and L-carnitine are taken up by separate highly specific transport systems and support a secondary transport mechanism for betaine uptake in L. monocytogenes. The initial uptake rates of betaine and L-carnitine are not influenced by an osmotic upshock, but the duration of transport of both osmolytes is directly related to the osmotic strength of the medium. Regulation of uptake of both betaine and L-carnitine is subject to inhibition by preaccumulated solute. Internal betaine inhibits not only transport of external betaine but also that of L-carnitine and, similarly, internal L-carnitine inhibits transport of both betaine and L-carnitine. The inhibition is alleviated upon osmotic upshock, which suggests that alterations in membrane structure are transmitted to the allosteric binding sites for betaine and L-carnitine of both transporters at the inner surface of the membrane. Upon osmotic downshock, betaine and L-carnitine are rapidly released by L. monocytogenes as a consequence of activation of a channel-like activity. The osmolyte-sensing mechanism described is new and is consistent with various unexplained observations of osmoregulation in other bacteria. PMID- 9371444 TI - Butyrolactone autoregulator receptor protein (BarA) as a transcriptional regulator in Streptomyces virginiae. AB - BarA of Streptomyces virginiae is a specific receptor protein for virginiae butanolides (VBs), a member of the butyrolactone autoregulators of Streptomyces species. Sequencing around the barA gene revealed two novel open reading frames: one upstream, barX, encoding a homolog of AfsA of Streptomyces griseus and another downstream, barB. Northern (RNA) blot analysis for S. virginiae demonstrated that the addition of VB during cultivation switched on the expression of barB. An in vivo expression system in Streptomyces lividans with the use of the xylE reporter gene indicated that BarA in conjunction with VB controlled the barB promoter. Furthermore, the DNA binding ability of BarA was demonstrated in vitro for the first time by means of surface plasmon resonance and a gel-shift assay. Complex formation with VB in vitro resulted in the dissociation of BarA from DNA, thus suggesting that the VB receptor, BarA, is a transcriptional regulator and that the VB signal is transduced to the next step in the signal transduction pathway by modification of the DNA binding ability of BarA. PMID- 9371446 TI - Use of steroids to monitor alterations in the outer membrane of Pseudomonas aeruginosa. AB - Testosterone (a strongly hydrophobic steroid) and testosterone hemisuccinate (a negatively charged derivative) were used as probes to investigate alterations in the outer membrane of Pseudomonas aeruginosa. Diffusion rates of the steroids across the lipid bilayer were measured by coupling the influx of these compounds to their subsequent oxidation by an intracellular delta1-dehydrogenase enzyme. Wild-type cells of P. aeruginosa (strain PAO1) were found to be 25 times more permeable to testosterone than to testosterone hemisuccinate. The uptake of the latter compound appeared to be partially dependent on the external pH, thus suggesting a preferential diffusion of the uncharged protonated form across the cell envelope. Using various PAO mutants, we showed that the permeation of steroids was not affected by overexpression of active efflux systems but was increased up to 5.5-fold when the outer membrane contained defective lipopolysaccharides or lacked the major porin OprF. Such alterations in the hydrophobic uptake pathway were not, however, associated with an enhanced permeability of the mutants to the small hydrophilic molecule N,N,N',N' tetramethyl-p-phenylene diamine. Thirty-six agents were also assayed for their ability to damage the cell surface of strain PAO1, using testosterone as a probe. Polymyxins, rBPI23, chlorhexidine, and dibromopropamidine demonstrated the strongest permeabilizing activities on a molar basis in the presence of 1 mM MgCl2. These amphiphilic polycations increased the transmembrane diffusion of testosterone up to 50-fold and sensitized the PAO1 cells to hydrophobic antibiotics. All together, these data indicated that the steroid uptake assay provides a direct and accurate measurement of the hydrophobic uptake pathway in P. aeruginosa. PMID- 9371445 TI - General secretion pathway (eps) genes required for toxin secretion and outer membrane biogenesis in Vibrio cholerae. AB - The general secretion pathway (GSP) of Vibrio cholerae is required for secretion of proteins including chitinase, enterotoxin, and protease through the outer membrane. In this study, we report the cloning and sequencing of a DNA fragment from V. cholerae, containing 12 open reading frames, epsC to -N, which are similar to GSP genes of Aeromonas, Erwinia, Klebsiella, Pseudomonas, and Xanthomonas spp. In addition to the two previously described genes, epsE and epsM (M. Sandkvist, V. Morales, and M. Bagdasarian, Gene 123: 81-86, 1993; L. J. Overbye, M. Sandkvist, and M. Bagdasarian, Gene 132:101-106, 1993), it is shown here that epsC, epsF, epsG, and epsL also encode proteins essential for GSP function. Mutations in the eps genes result in aberrant outer membrane protein profiles, which indicates that the GSP, or at least some of its components, is required not only for secretion of soluble proteins but also for proper outer membrane assembly. Several of the Eps proteins have been identified by use of the T7 polymerase-promoter system in Escherichia coli. One of them, a pilin-like protein, EpsG, was analyzed also in V. cholerae and found to migrate as two bands on polyacrylamide gels, suggesting that in this organism it might be processed or otherwise modified by a prepilin peptidase. We believe that TcpJ prepilin peptidase, which processes the subunit of the toxin-coregulated pilus, TcpA, is not involved in this event. This is supported by the observations that apparent processing of EpsG occurs in a tcpJ mutant of V. cholerae and that, when coexpressed in E. coli, TcpJ cannot process EpsG although the PilD peptidase from Neisseria gonorrhoeae can. PMID- 9371447 TI - Glutamate residues located within putative transmembrane helices are essential for TetA(P)-mediated tetracycline efflux. AB - The tetA(P) gene from Clostridium perfringens encodes a unique membrane protein that is responsible for the active efflux of tetracycline from resistant cells. The novel TetA(P) protein has neither the typical structure nor the conserved motifs that are found in tetracycline efflux proteins from classes A through H or classes K and L. Site-directed mutagenesis of selected residues within TetA(P) was performed to elucidate their role in tetracycline efflux. Glutamate residues 52 and 59, negatively charged residues located within putative transmembrane helix 2, could not be replaced by either glutamine or aspartate and so were essential for tetracycline efflux. Replacement of Glu89, which was located at the end of helix 3, by aspartate but not by glutamine allowed TetA(P) function, indicating the importance of a carboxyl group at this position. After mutation of the Asp67 residue, located within cytoplasmic loop 1, no immunoreactive protein was detected. It is concluded that negatively charged residues that appear to be located within or near the membrane are important for the function of TetA(P). PMID- 9371448 TI - Dual function of the copR gene product of plasmid pIP501. AB - Replication of plasmid pIP501 is regulated at a step subsequent to transcription initiation by an antisense RNA (RNAIII) and transcriptionally by a repressor protein, CopR. Previously, it had been shown that CopR binds to a 44-bp DNA fragment upstream of and overlapping the repR promoter pII. Subsequently, we found that high-copy-number pIP501 derivatives lacking copR and low-copy-number derivatives containing copR produced the same intracellular amounts of RNAIII. This suggested a second, hitherto-unknown function of CopR. In this report, we show that CopR does not affect the half-life of RNAIII. Instead, we demonstrate in vivo that, in the presence of both pII and pIII, CopR provided in cis or in trans causes an increase in the intracellular concentration of RNAIII and that this effect is due to the function of the protein rather than its mRNA. We suggest that, in the absence of CopR, the increased (derepressed) RNAII transcription interferes, in cis, with initiation of transcription of RNAIII (convergent transcription), resulting in a lower RNAIII/plasmid ratio. When CopR is present, the pII promoter is repressed to >90%, so that convergent transcription is mostly abolished and RNAIII/plasmid ratios are high. The hypothesis that RNAII transcription influences promoter pIII through induced changes in DNA supercoiling is supported by the finding that the gyrase inhibitor novobiocin affects the accumulation of both sense and antisense RNA. The dual role of CopR in repression of RNAII transcription and in prevention of convergent transcription is discussed in the context of replication control of pIP501. PMID- 9371449 TI - Organization and regulation of the D-xylose operons in Escherichia coli K-12: XylR acts as a transcriptional activator. AB - The metabolism of D-xylose in Escherichia coli K-12 is known to be mediated by the xylAB gene. However, the nearby xylFGHR genes were found by genome sequencing and predicted to be responsible for transport and regulation for xylose based on their sequence similarities to other functionally related genes. Here, we investigated transcriptional organization and functions of the xyl genes. An analysis with random transposon insertions revealed that the xyl genes are organized into two major transcriptional units, xylAB and xylFGHR, governed by the promoters PA and PF, respectively. However, there is an additional weak promoter, PR, which is specific for xylR. Sites of transcription initiation were determined by primer extension analysis. When studied with operon fusions to lacZ, the PA and PF promoters were activated by D-xylose and repressed by glucose. In contrast, the PR promoter was not regulated by these sugars. A mutation in xylR completely abolished expression from the PA and PF promoters, causing a defect in both growth and transport. Binding of XylR to the xyl promoter was enhanced by the presence of D-xylose, suggesting that transcription was positively regulated by XylR. In vivo footprinting analysis revealed that XylR binds to at least two DNA regions, IA and IF, each with a direct repeat. It is very likely that XylR interacts with IA and IF as a dimer. The presumed binding sites are located just upstream of the promoter consensus sequences ( 35), while IA is additionally flanked by a cyclic AMP receptor protein-binding site on the other side. The proposed structure of xyl promoters is consistent with the regulation of xyl gene expression and with phenotypes of transposon insertions obtained in the promoter regions. PMID- 9371451 TI - Regulation of polymyxin resistance and adaptation to low-Mg2+ environments. AB - The PmrA-PmrB two-component system of Salmonella typhimurium controls resistance to the peptide antibiotic polymyxin B and to several antimicrobial proteins from human neutrophils. Amino acid substitutions in the regulatory protein PmrA conferring resistance to polymyxin lower the overall negative charge of the lipopolysaccharide (LPS), which results in decreased bacterial binding to cationic polypeptides and increased bacterial survival within human neutrophils. We have now identified three PmrA-activated loci that are required for polymyxin resistance. These loci were previously shown to be necessary for growth on low Mg2+ solid media, indicating that LPS modifications that mediate polymyxin resistance are responsible for the adaptation to Mg2+-limited environments. Conditions that promote transcription of PmrA-activated genes--growth in mildly acidic pH and micromolar Mg2+ concentrations--increased survival in the presence of polymyxin over 16,000-fold in a wild-type organism but not in a mutant lacking pmrA. Our experiments suggest that low pH and low Mg2+ concentrations may induce expression of PmrA-activated genes within phagocytic cells and promote bacterial resistance to host antimicrobial proteins. We propose that the LPS is a Mg2+ reservoir and that the PmrA-controlled LPS modifications neutralize surface negative charges when Mg2+ is transported into the cytoplasm during growth in Mg2+-limited environments. PMID- 9371450 TI - Regulation of Bacteriodes fragilis katB mRNA by oxidative stress and carbon limitation. AB - Regulation of the katB catalase gene in the anaerobic bacterium Bacteroides fragilis was studied. Northern blot hybridization analyses revealed that katB was transcribed as an approximately 1.6-kb monocistronic mRNA. The levels of katB mRNA increased > 15-fold when anaerobic, mid-logarithmic-phase cultures were exposed to O2, O2 with paraquat, or hydrogen peroxide. Under anaerobic conditions, the low levels of katB mRNA increased in a growth-dependent manner, reaching maximum expression at late logarithmic or early stationary phase, followed by a decrease in stationary phase. Under anaerobic conditions, the expression of katB mRNA was strongly repressed by glucose and to a lesser extent by xylose. However, glucose repression was completely abolished upon exposure to oxygen. The nonfermentable carbon sources fumarate, succinate, acetate, and pyruvate did not significantly affect expression. Phosphate, nitrogen, and hemin limitation did not affect the expression of katB mRNA, suggesting that the nutritional control of katB expression is restricted to carbon and energy sources and not other forms of nutrient limitation. Primer extension analysis revealed that during both oxidative stress and carbon or energy limitation, katB utilized the same promoter region but transcription initiation occurred at two different nucleotides separated by 3 or 4 bases. Interestingly, a 6-bp inverted repeat sequence present in the katB regulatory region was also observed upstream of the B. fragilis superoxide dismutase gene sod. It is possible that this is a recognition site for a DNA binding protein involved in the regulation of oxidative stress genes in this organism. PMID- 9371452 TI - Analysis of the Bacillus subtilis S10 ribosomal protein gene cluster identifies two promoters that may be responsible for transcription of the entire 15-kilobase S10-spc-alpha cluster. AB - We have sequenced a previously uncharacterized region of the Bacillus subtilis S10 ribosomal protein gene cluster. The new segment includes genes for S10, L3, L4, L23, L2, S19, L22, S3, and part of L16. These B. subtilis genes map in the same order as the genes in the Escherichia coli S10 ribosomal protein operon. Two potential promoter sequences were identified, one approximately 200 bases and the other approximately 140 bases upstream of the S10 gene. The activities of the two promoters were demonstrated by primer extension analysis, in vitro transcription experiments, and in vivo promoter fusion plasmid studies. In agreement with previous reports, our Northern analysis of exponentially growing cells failed to identify terminators or other active promoters within the S10-spc-alpha region. Our observations suggest that the two S10 promoters reported here are responsible for transcribing a 15-kb-long transcript for all of the genes in the B. subtilis S10, spc, and alpha clusters. PMID- 9371454 TI - Temperature-dependent regulation of the ribosomal small-subunit protein S21 in the cyanobacterium Anabaena variabilis M3. AB - The rpsU gene, which encodes the ribosomal small-subunit protein S21 in Anabaena, is not a part of the macromolecular-synthesis operon as in most enterobacteria but rather is located downstream of the rbpA1 gene, which encodes an RNA-binding protein. Two types of transcripts were detected for this gene cluster. The level of the major rbpA1-rpsU transcript was about 10 times higher at 22 degrees C than at 38 degrees C, whereas the minor monocistronic rpsU transcript was more abundant at the higher temperature. The level of the S21 protein in relation to total protein was three times lower at 38 degrees C than at 22 degrees C. Analysis of isolated ribosomes indicated that S21 was present at an equimolar ratio with regard to other ribosomal proteins at 22 degrees C but that its level decreased with temperature. Conversely, the relative abundance of S5 increased with temperature. A decrease in the level of S21 at high temperature was also found in Synechocystis, in which rpsU is located downstream of the rrn operon. These results suggest that S21 is involved in the adaptation to changes in temperature in cyanobacteria. PMID- 9371453 TI - Cloning of a Vibrio cholerae vibriobactin gene cluster: identification of genes required for early steps in siderophore biosynthesis. AB - Vibrio cholerae secretes the catechol siderophore vibriobactin in response to iron limitation. Vibriobactin is structurally similar to enterobactin, the siderophore produced by Escherichia coli, and both organisms produce 2,3 dihydroxybenzoic acid (DHBA) as an intermediate in siderophore biosynthesis. To isolate and characterize V. cholerae genes involved in vibriobactin biosynthesis, we constructed a genomic cosmid bank of V. cholerae DNA and isolated clones that complemented mutations in E. coli enterobactin biosynthesis genes. V. cholerae homologs of entA, entB, entC, entD, and entE were identified on overlapping cosmid clones. Our data indicate that the vibriobactin genes are clustered, like the E. coli enterobactin genes, but the organization of the genes within these clusters is different. In this paper, we present the organization and sequences of genes involved in the synthesis and activation of DHBA. In addition, a V. cholerae strain with a chromosomal mutation in vibA was constructed by marker exchange. This strain was unable to produce vibriobactin or DHBA, confirming that in V. cholerae VibA catalyzes an early step in vibriobactin biosynthesis. PMID- 9371456 TI - CspA, the major cold shock protein of Escherichia coli, negatively regulates its own gene expression. AB - When the gene for CspA, the major cold shock protein of Escherichia coli, was disrupted by a novel positive/negative selection method, the deltacspA cells did not show any discernible growth defect at either 37 or 15 degrees C. By two dimensional gel electrophoresis, total protein synthesis was analyzed after temperature downshift in the deltacspA strain. The production of the CspA homologs CspB and CspG increased, and the duration of their expression was prolonged, suggesting that both CspB and CspG compensate for the function of CspA in the absence of CspA during cold shock adaptation. Interestingly, the production of the 159-base 5'-untranslated region (5'-UTR) of cspA from the chromosomal cspA::cat gene, detected by primer extension, failed to be repressed after cold shock. When an independent system to produce CspA was added to the deltacspA strain, the 5'-UTR production for the cspA::cat gene was significantly reduced compared to that of the deltacspA strain. By examining the expression of translationally fused cspA and cspB genes to lacZ in the deltacspA strain, it was found that cspA is more strongly regulated by CspA than cspB is. We showed that the increased expression of the 5'-UTR of the cspA mRNA in the deltacspA strain occurred mainly at the level of transcription and, to a certain extent, at the level of mRNA stabilization. The mRNA stabilization in the deltacspA strain was observed for other mRNAs, supporting the notion that CspA functions as an mRNA chaperone to destabilize secondary structures in mRNAs. PMID- 9371455 TI - Characterization of the Vibrio cholerae El Tor lipase operon lipAB and a protease gene downstream of the hly region. AB - We have cloned and sequenced a region encoding a lipase operon and a putative, previously uncharacterized metalloprotease of Vibrio cholerae O1. These lie downstream of hlyA and hlyB, which encode the El Tor hemolysin and methyl accepting chemotactic factor, respectively. Previous reports identified the hlyC gene downstream of hlyAB, encoding an 18.3-kDa protein. However, we now show that this open reading frame (ORF) encodes a 33-kDa protein, and since the amino acid sequence is highly homologous to the triacylglyceride-specific lipase of Pseudomonas spp., hlyC has been renamed lipA. LipA contains the highly conserved pentapeptide and catalytic triad amino acid regions of the catalytic sites of other lipases. The region downstream of lipA has been sequenced and has revealed ORFs lipB and prtV. The amino acid sequence of lipB is homologous to those of the accessory lipase proteins (lipase-specific foldase) required by Pseudomonas and various other bacterial species for the production of mature active lipase, and in agreement with this, we show that both lipA and lipB are required to restore a lipase-deficient lipA null mutant of V. cholerae. The intergenic stop codon for lipA overlaps the ribosome-binding site for lipB, and a stem-loop resembling a rho-independent terminator is present immediately downstream from lipB, suggesting that lipA and lipB form a lipase operon in V. cholerae. prtV lies downstream of lipAB but is transcribed in the opposite direction and is predicted to share the same putative transcriptional terminator with lipAB. The zinc binding and catalytic domains conserved among many metalloproteases are present in PrtV, which is highly homologous to the immune inhibitor A (InA) metalloprotease of Bacillus thuringiensis. PrtV was visualized as approximately 102 kDa, which is consistent with the coding capacity of the gene. The genetic organization of this region suggests that it is possibly part of a pathogenicity island, encoding products capable of damaging host cells and/or involved in nutrient acquisition by V. cholerae. However, neither lipA nor prtV null mutants were attenuated in the infant mouse model, nor did they exhibit reduced colonization potential compared with wild type in competition experiments. PMID- 9371457 TI - Hierarchical autoinduction in Ralstonia solanacearum: control of acyl-homoserine lactone production by a novel autoregulatory system responsive to 3 hydroxypalmitic acid methyl ester. AB - Bacteria employ autoinduction systems to sense the onset of appropriate cell density for expression of developmental genes. In many gram-negative bacteria, autoinduction involves the production of and response to diffusible acylated homoserine lactones (acyl-HSLs) and is mediated by members of the LuxR and LuxI families. Ralstonia (Pseudomonas) solanacearum, a phytopathogenic bacterium that appears to autoregulate its virulence genes, produces compounds that promote expression of several heterologous acyl-HSL-responsive reporter gene constructs. High-pressure liquid chromatography of highly concentrated ethyl acetate extracts revealed that culture supernatants of strain AW1 contained two compounds with retention times similar to N-hexanoyl- and N-octanoyl-HSL. To investigate the role of these acyl-HSLs in R. solanacearum virulence gene expression, transposon mutants that were deficient for inducing an acyl-HSL-responsive reporter in Agrobacterium tumefaciens were generated. Three loci involved in normal acyl-HSL production were identified, one of which was shown to contain the divergently transcribed solR and solI genes, the luxR and luxI homologs, respectively. A 4.1 kb fragment containing solR and solI enabled all of the mutants (regardless of the locus inactivated) and a naturally acyl-HSL-defective strain of R. solanacearum to produce acyl-HSLs. Inactivation of solI abolished production of all detectable acyl-HSLs but affected neither the expression of virulence genes in culture nor the ability to wilt tomato plants. AW1 has a functional autoinduction system, because (i) expression of solI required SolR and acyl-HSL and (ii) expression of a gene linked to solR and solI, designated aidA, was acyl HSL dependent. Because AidA has no homologs in the protein databases, its discovery provided no clues as to the role of acyl-HSLs in R. solanacearum gene regulation. However, expression of solR and solI required the global LysR-type virulence regulator PhcA, and both solR and solI exhibited a cell density associated pattern of expression similar to other PhcA-regulated genes. The acyl HSL-dependent autoinduction system in R. solanacearum is part of a more complex autoregulatory hierarchy, since the transcriptional activity of PhcA is itself controlled by a novel autoregulatory system that responds to 3-hydroxypalmitic acid methyl ester. PMID- 9371458 TI - Propionyl coenzyme A carboxylase is required for development of Myxococcus xanthus. AB - A dcm-1 mutant, obtained by transposon mutagenesis of Myxococcus xanthus, could aggregate and form mounds but was unable to sporulate under nutrient starvation. A sequence analysis of the site of insertion of the transposon showed that the insertion lies within the 3' end of a 1,572-bp open reading frame (ORF) designated the M. xanthus pccB ORF. The wild-type form of the M. xanthus pccB gene, obtained from a lambdaEMBL library of M. xanthus, shows extensive similarity to a beta subunit of propionyl coenzyme A (CoA) carboxylase, an alpha subunit of methylmalonyl-CoA decarboxylase, and a 12S subunit of transcarboxylase. In enzyme assays, extracts of the dcm-1 mutant were deficient in propionyl-CoA carboxylase activity. This enzyme catalyzes the ATP-dependent carboxylation of propionyl-CoA to yield methylmalonyl-CoA. The methylmalonyl-CoA rescued the dcm-1 mutant fruiting body and spore development. During development, the dcm-1 mutant cells also had reduced levels of long-chain fatty acids (C16 to C18) compared to wild-type cells. PMID- 9371460 TI - Genetic analysis of the chitinase system of Serratia marcescens 2170. AB - To carry out a genetic analysis of the degradation and utilization of chitin by Serratia marcescens 2170, various Tn5 insertion mutants with characteristic defects in chitinase production were isolated and partially characterized. Prior to the isolation of the mutants, proteins secreted into culture medium in the presence of chitin were analyzed. Four chitinases, A, B, C1, and C2, among other proteins, were detected in the culture supernatant of S. marcescens 2170. All four chitinases and a 21-kDa protein (CBP21) lacking chitinase activity showed chitin binding activity. Cloning and sequencing analysis of the genes encoding chitinases A and B of strain 2170 revealed extensive similarities to those of other strains of S. marcescens described previously. Tn5 insertion mutagenesis of strain 2170 was carried out, and mutants which formed altered clearing zones of colloidal chitin were selected. The obtained mutants were divided into five classes as follows: mutants with (i) no clearing zones, (ii) fuzzy clearing zones, (iii) large clearing zones, (iv) delayed clearing zones, and (v) small clearing zones. Preliminary characterization suggested that some of these mutants have defects in chitinase excretion, a negatively regulating mechanism of chitinase gene expression, an essential factor for chitinase gene expression, and a structural gene for a particular chitinase. These mutants could allow researchers to identify the genes involved in the degradation and utilization of chitin by S. marcescens 2170. PMID- 9371459 TI - Unusual structure of the tonB-exb DNA region of Xanthomonas campestris pv. campestris: tonB, exbB, and exbD1 are essential for ferric iron uptake, but exbD2 is not. AB - The nucleotide sequence of a 3.6-kb HindIII-SmaI DNA fragment of Xanthomonas campestris pv. campestris revealed four open reading frames which, based on sequence homologies, were designated tonB, exbB, exbD1, and exbD2. Analysis of translational fusions to alkaline phosphatase and beta-galactosidase confirmed that the TonB, ExbB, ExbD1, and ExbD2 proteins are anchored in the cytoplasmic membrane. The TonB protein of X. campestris pv. campestris lacks the conserved (Glu-Pro)n and (Lys-Pro)m repeats but harbors a 13-fold repeat of proline residues. By mutational analysis, the tonB, exbB, and exbD1 genes were shown to be essential for ferric iron import in X. campestris pv. campestris. In contrast, the exbD2 gene is not involved in the uptake of ferric iron. PMID- 9371461 TI - pCal, a highly unusual Ty1/copia retrotransposon from the pathogenic yeast Candida albicans. AB - Retrotransposons are mobile genetic elements. They can transpose via the reverse transcription of mRNA into double-stranded DNA (dsDNA) followed by the insertion of this dsDNA into new sites within the host genome. The unintegrated, linear, dsDNA form of retrotransposons is usually very rare. We report here the isolation of a retrotransposon from Candida albicans which is unusual in this respect. This element, which we have named pCal, was first identified as a distinct band when uncut C. albicans DNA was examined on an agarose gel. Sequence analysis of the cloned element revealed that it is a retrotransposon belonging to the Ty1/copia group. It is estimated that pCal produces 50 to 100 free, linear, dsDNA copies of itself per cell. This is a much higher level of expression than even that of the system in which Ty1 is expressed behind the highly active GAL1 promoter on a high copy-number plasmid (about 10 copies per cell). Another unusual feature of pCal is that its Pol enzymes are likely to be expressed via the pseudoknot-assisted suppression of an upstream, in-phase stop codon, as has been shown for Moloney murine leukemia virus. PMID- 9371462 TI - Regulation of expression of the ethanol dehydrogenase gene (adhE) in Escherichia coli by catabolite repressor activator protein Cra. AB - The adhE gene encodes ethanol dehydrogenase and is located at min 27.9 of the Escherichia coli chromosome. Expression of adhE is about 10-fold higher in cells grown anaerobically than in cells grown aerobically and is dependent on both transcriptional and posttranscriptional factors. In this study, a trans regulatory element repressing adhE expression was characterized by genetic and biochemical approaches. A mutation downregulating adhE expression was mapped at min 2 of the chromosome. DNA sequence analysis revealed a missense mutation in the cra gene, formerly known as fruR. The cra gene encodes a catabolite repressor activator protein (Cra) involved in the modulation of carbon flow in E. coli. The mutant protein (Cra*) sustained an Arg148-->His substitution causing 1.5- and 3 fold stronger repression of adhE transcription under anaerobic and aerobic conditions, respectively. By contrast, cra null mutants displayed 1.5- and 4-fold increased adhE transcription under those conditions. Disruption of the cra gene did not abolish the anaerobic activation of the adhE gene but diminished it twofold. Cra and Cra* were purified as fusion proteins tagged with an N-terminal 6xHis element. In vitro, both fusion proteins showed binding to the adhE promoter region and to the control fruB promoter region, which is a known Cra target. However, only 6xHis-tagged Cra, and not 6xHis-Cra*, was displaced from the DNA target by the effector, fructose-1-phosphate (F1P), suggesting that the mutant protein is locked in a promoter-binding conformation and is no longer responsive to F1P. We suggest that Cra helps to tighten the control of adhE transcription under aerobic conditions by its repression. PMID- 9371464 TI - Designing recombinant Pseudomonas strains to enhance biodesulfurization. AB - The dsz biodesulfurization cluster from Rhodococcus erythropolis IGTS8 has been engineered under the control of heterologous broad-host-range regulatory signals to alleviate the mechanism of sulfur repression, and it was stably inserted into the chromosomes of different Pseudomonas strains. The recombinant bacteria were able to desulfurize dibenzothiophene more efficiently than the native host. Furthermore, these new biocatalysts combine relevant industrial and environmental traits, such as production of biosurfactants, with the enhanced biodesulfurization phenotype. PMID- 9371463 TI - Complete genome sequence of Methanobacterium thermoautotrophicum deltaH: functional analysis and comparative genomics. AB - The complete 1,751,377-bp sequence of the genome of the thermophilic archaeon Methanobacterium thermoautotrophicum deltaH has been determined by a whole-genome shotgun sequencing approach. A total of 1,855 open reading frames (ORFs) have been identified that appear to encode polypeptides, 844 (46%) of which have been assigned putative functions based on their similarities to database sequences with assigned functions. A total of 514 (28%) of the ORF-encoded polypeptides are related to sequences with unknown functions, and 496 (27%) have little or no homology to sequences in public databases. Comparisons with Eucarya-, Bacteria-, and Archaea-specific databases reveal that 1,013 of the putative gene products (54%) are most similar to polypeptide sequences described previously for other organisms in the domain Archaea. Comparisons with the Methanococcus jannaschii genome data underline the extensive divergence that has occurred between these two methanogens; only 352 (19%) of M. thermoautotrophicum ORFs encode sequences that are >50% identical to M. jannaschii polypeptides, and there is little conservation in the relative locations of orthologous genes. When the M. thermoautotrophicum ORFs are compared to sequences from only the eucaryal and bacterial domains, 786 (42%) are more similar to bacterial sequences and 241 (13%) are more similar to eucaryal sequences. The bacterial domain-like gene products include the majority of those predicted to be involved in cofactor and small molecule biosyntheses, intermediary metabolism, transport, nitrogen fixation, regulatory functions, and interactions with the environment. Most proteins predicted to be involved in DNA metabolism, transcription, and translation are more similar to eucaryal sequences. Gene structure and organization have features that are typical of the Bacteria, including genes that encode polypeptides closely related to eucaryal proteins. There are 24 polypeptides that could form two-component sensor kinase-response regulator systems and homologs of the bacterial Hsp70-response proteins DnaK and DnaJ, which are notably absent in M. jannaschii. DNA replication initiation and chromosome packaging in M. thermoautotrophicum are predicted to have eucaryal features, based on the presence of two Cdc6 homologs and three histones; however, the presence of an ftsZ gene indicates a bacterial type of cell division initiation. The DNA polymerases include an X-family repair type and an unusual archaeal B type formed by two separate polypeptides. The DNA-dependent RNA polymerase (RNAP) subunits A', A", B', B" and H are encoded in a typical archaeal RNAP operon, although a second A' subunit-encoding gene is present at a remote location. There are two rRNA operons, and 39 tRNA genes are dispersed around the genome, although most of these occur in clusters. Three of the tRNA genes have introns, including the tRNAPro (GGG) gene, which contains a second intron at an unprecedented location. There is no selenocysteinyl-tRNA gene nor evidence for classically organized IS elements, prophages, or plasmids. The genome contains one intein and two extended repeats (3.6 and 8.6 kb) that are members of a family with 18 representatives in the M. jannaschii genome. PMID- 9371465 TI - Plasmid pRQ7 from the hyperthermophilic bacterium Thermotoga species strain RQ7 replicates by the rolling-circle mechanism. AB - The hyperthermophilic bacterium Thermotoga species strain RQ7 harbors an 846-bp plasmid, pRQ7, with a single open reading frame. Previously published analyses of the DNA sequence of pRQ7 suggested that it may replicate by a rolling-circle (RC) replication mechanism, and this report provides experimental evidence supporting this hypothesis. Single-stranded pRQ7 DNA accumulates in strain RQ7, as evidenced by the facts that this DNA bound to nitrocellulose membranes under nondenaturing conditions, was sensitive to S1 nuclease digestion, and hybridized to only one of two homologous DNA probes specific for each strand of the plasmid. The DNA encoding the open reading frame was cloned and expressed in Escherichia coli and gave a protein with a molecular mass of 26 kDa, similar to that deduced by sequence analysis. This protein bound to a fragment of pRQ7 that contains a putative double-stranded replication region in a magnesium-dependent reaction and made this fragment sensitive to S1 nuclease activity. It did not cause this same S1 nuclease sensitivity in the remainder of pRQ7. This activity on pRQ7 DNA suggests that this protein plays a role in plasmid replication. PMID- 9371466 TI - Identification of type III secreted products of the Pseudomonas aeruginosa exoenzyme S regulon. AB - Extracellular protein profiles from wild-type and regulatory or secretory isogenic mutants of the Pseudomonas aeruginosa exoenzyme S regulon were compared to identify proteins coordinately secreted with ExoS. Data from amino-terminal sequence analysis of purified extracellular proteins were combined with data from nucleotide sequence analysis of loci linked to exoenzyme S production. We report the identification of P. aeruginosa homologs to proteins of Yersinia spp. that function as regulators of the low calcium response, regulators of secretion, and mediators of the type III translocation mechanism. PMID- 9371467 TI - Evidence for transcription attenuation rendering cryptic a sigmaS-dependent promoter of the osmotically regulated proU operon of Salmonella typhimurium. AB - The osmotically regulated proU locus in Escherichia coli has two promoters, P1 and P2, that are recognized, respectively, by the sigmaS- and sigma70-bearing RNA polymerase holoenzymes. However, the equivalent of the P1 promoter does not appear to exist in Salmonella typhimurium. We demonstrate in this study that wild type S. typhimurium has a cryptic P1 promoter that is recognized by sigmaS RNA polymerase in vitro and that a 22-bp deletion from +63 to +84 (relative to the start site of transcription) confers sigmaS-dependent in vivo expression of a reporter gene fusion to P1. Primer extension analysis of RNA isolated from cells carrying the wild-type and mutant S. typhimurium proU constructs indicated that a primer which hybridizes proximal to +60 is able to detect P1-initiated transcripts from both constructs but a primer which hybridizes distal to +85 is able to do so only from the latter. Our results suggest that the sigmaS controlled proU P1 promoter in S. typhimurium may be rendered cryptic because of factor-dependent transcription attenuation within a short distance downstream of the promoter start site. PMID- 9371468 TI - Glucose-1-phosphate utilization by Listeria monocytogenes is PrfA dependent and coordinately expressed with virulence factors. AB - Virulence genes of the facultative intracellular pathogen Listeria monocytogenes are coordinately regulated by the activator protein PrfA, encoded by prfA, a member of the cyclic AMP receptor protein family of bacterial transcription factors. We found that prfA* mutants that constitutively overexpress the virulence regulon due to a Gly145Ser substitution in PrfA (M.-T. Ripio, G. Dominguez-Bernal, M. Lara, M. Suarez, and J.-A. Vazquez-Boland, J. Bacteriol. 179:1533-1540, 1997) rapidly utilized glucose-1-phosphate (G-1-P) as a carbon source for growth, in contrast to wild-type strains, which characteristically do not. Wild-type strains acquired the capacity for readily metabolizing G-1-P upon exposure to environmental conditions that activate the expression of prfA and PrfA-dependent virulence genes (i.e., culture at 37 degrees C in charcoal-treated medium). In these strains, G-1-P utilization followed an expressional pattern identical to that of virulence genes controlled by PrfA, with repression at 20 degrees C. Tn917 insertions in L. monocytogenes mutants selected for G-1-P utilization deficiency mapped to the plcA-prfA operon, a deltaprfA strain was totally unable to utilize G-1-P, and trans complementation with prfA constructs restored the ability to efficiently metabolize and grow on G-1-P to these mutants. Thus, G-1-P utilization by L. monocytogenes is under the tight positive control of the central virulence regulator, PrfA, and is coexpressed with PrfA dependent pathogenicity determinants. It was recently reported that readily utilized carbohydrates, such as glucose or cellobiose, repress virulence genes in L. monocytogenes. We confirmed this but, interestingly, found that G-1-P does not inhibit expression of the PrfA regulon, indicating that this sugar follows a catabolic pathway that bypasses the repressor mechanism triggered by other readily metabolized carbon sources. PrfA dependence and coexpression with virulence genes suggest that utilization of exogenous G-1-P may be relevant to Listeria pathogenesis. G-1-P is the precursor metabolite and primary degradation product of glycogen and is therefore available within the mammalian cell. Based on our results, we hypothesize that G-1-P could play an important role as a growth substrate for intracellular Listeria. PMID- 9371469 TI - Characterization of Bacillus subtilis hemN. AB - A recently cloned Bacillus subtilis open reading frame (hemN) upstream of the dnaK operon was identified as encoding a protein involved in oxygen-independent coproporphyrinogen III decarboxylation. B. subtilis hemN functionally complemented two Salmonella typhimurium hemF hemN double mutants under aerobic and anaerobic conditions. A B. subtilis hemN mutant accumulated coproporphyrinogen III only under anaerobic conditions. Interestingly, growth experiments using the B. subtilis hemN mutant revealed normal aerobic and anaerobic growth, indicating the presence of an alternative oxygen-independent enzymatic system. Northern blot experiments identified hemN mRNA as part of an approximately 7-kb pentacistronic transcript consisting of lepA, hemN, hrcA, grpE, and dnaK. One potential start site for aerobic and anaerobic transcription was located 37 bp upstream of the translational start codon of lepA. Comparable amounts of hemN transcript were observed under aerobic and anaerobic growth conditions. No experimental evidence for the presence of hemF in B. subtilis was obtained. Moreover, B. subtilis hemY did not substitute for hemF hemN deficiency in S. typhimurium. These results indicate the absence of hemF and suggest the presence of a second hemN-like gene in B. subtilis. PMID- 9371470 TI - Influence of genes encoding proton-translocating enzymes on suppression of Salmonella typhimurium growth and colonization. AB - Twenty-four-hour-old, aerobically grown, Luria-Bertani broth cultures of Salmonella typhimurium F98 suppressed the growth of a spectinomycin-resistant (Spcr) derivative of the same strain inoculated at 10(3) CFU ml(-1). This growth suppression is genus specific and RpoS independent, and it is not solely a result of nutrient depletion (P. A. Barrow, M. A. Lovell, and L. Zhang-Barber, J. Bacteriol. 178:3072-3076, 1996). Mutations in three genes are shown here to significantly reduce growth suppression under these conditions. The mutations were located in the nuo, cyd, and unc operons, which code for the NADH dehydrogenase I, cytochrome d oxidase, and F0F1 proton-translocating ATPase complexes, respectively. When cultures were grown under strictly anaerobic conditions, only the unc mutant did not suppress growth. Prior colonization of the alimentary tract of newly hatched chickens with the S. typhimurium F98 wild type or nuo or cyd mutants suppressed colonization by an S. typhimurium F98 Spcr derivative inoculated 24 h later. In contrast, the S. typhimurium unc mutant did not suppress colonization. The nuo and unc mutants showed poorer growth on certain carbon sources. The data support the hypothesis that growth suppression operates because of the absence of a utilizable carbon source or electron acceptor. PMID- 9371472 TI - Carbonic anhydrase in Acetobacterium woodii and other acetogenic bacteria. AB - Acetobacterium woodii, Acetohalobium arabaticum, Clostridium formicoaceticum, and Sporomusa silvacetica were found to contain carbonic anhydrase (CA). Minimal to no CA activity was detected in Moorella thermoautotrophica, Moorella thermoacetica subsp. "pratumsolum," Sporomusa termitida, and Thermoanaerobacter kivui. Of the acetogens tested, A. woodii had the highest CA specific activity, approximately 14 U mg of protein(-1), in extracts of either glucose- or H2-CO2 cultivated cells. CA of A. woodii was cytoplasmic and was purified approximately 300-fold to a specific activity of 5,236 U mg of protein(-1). Intracellular acetate concentrations inhibited CA activity of A. woodii by 50 to 85%, indicating that intracellular acetate may affect in situ CA activity. PMID- 9371473 TI - Problems in the assessment of glycaemic control in diabetes mellitus. AB - The measurement of glycated haemoglobin and serum fructosamine to assess the recent glycaemic control of diabetic patients has become well established. Likewise, the monitoring of blood glucose using glucose test strips and meters has become popular in both the community and in the hospital inpatient environment. However, despite improvements in the methods of analysis, clinically inaccurate assessments of glycaemia can still occur. Specific problems such as the lack of standardization in assays are in the process of being resolved, but inherent difficulties associated with these measures remain. Clinicians should be aware that these tests still need to be interpreted in conjunction with clinical prudence. PMID- 9371471 TI - Cytochrome c terminal oxidase pathways of Azotobacter vinelandii: analysis of cytochrome c4 and c5 mutants and up-regulation of cytochrome c-dependent pathways with N2 fixation. AB - The Azotobacter vinelandii cytochrome c5 gene (termed cycB) was cloned and sequenced. Mutants in this c-type cytochrome as well as cytochrome c4 mutants (mutations in cycA) and double mutants in both of the c-type respiratory pathways were characterized. Spectral and heme staining experiments on membranes from the mutants were consistent with the anticipated characteristics of all the gene directed mutants. Membranes of the individual cytochrome c4 or c5 mutants had normal respiratory rates with physiological substrates but respiration significantly lower than the wild-type rate with ascorbate-N,N,N',N',-tetramethyl p-phenylenediamine (TMPD) as a reductant. The growth rates of the individual cytochrome c4 or c5 mutants were not markedly different from that of the wild type strain, but the cycA cycB double-mutant strain was noticeably growth retarded at and below 7.5% O2 on both N-containing and N-free media. The double mutant strain was unable to grow on agar plates at O2 tensions of 2.5% or less on N-free medium. As the wild-type growth was unaffected by varying the O2 tension, the results indicate that the role of the cytochrome c-dependent pathways is to provide respiration at intermediate (5 to 10%) and low (below 5%) O2 tensions. The two c-type cytochrome genes are transcriptionally up-regulated with N2 fixation; N starvation caused 2.8-fold and 7- to 10-fold increases in the promoter activities of cycA and cycB, respectively, but these activities were affected little by the O2 level supplied to the cultures. PMID- 9371474 TI - Formation of plasma advanced glycosylation end products (AGEs) has no influence on plasma viscosity. AB - Plasma viscosity is mainly determined by large non-spherical proteins. In Type 1 diabetes mellitus, plasma viscosity increases with deterioration of diabetic control. Since protein glycation and formation of advanced glycosylation end products (AGEs) alter the structural and functional properties of proteins, AGEs might influence the rheological properties of plasma proteins. Therefore, we investigated the influence of plasma-AGEs on plasma viscosity in 34 normoalbuminuric diabetic patients (17 Type 1, 17 Type 2) with normal renal and liver function. In an additional experiment, 6 ml plasma of 9 healthy volunteers were incubated under sterile conditions for 14 days at 37.5 degrees C in the presence of 5.2 and 32.9 mmol l(-1) glucose. In diabetic patients, plasma-AGE levels were not correlated with plasma viscosity. Plasma-AGE levels in healthy controls (246 +/- 37 U ml[-1], mean +/- SD) were raised significantly (p<0.001) after the incubation at 37.5 degrees C (392 +/- 57 U ml[-1] and 552 +/- 58 U ml[ 1], respectively). However, no difference was found in plasma viscosity pre- and post-incubation (pre-incubation: 1.25 +/- 0.04 mPas, post-incubation: 1.23 +/- 0.03 and 1.24 +/- 0.03, respectively). We conclude that there is no influence of plasma-AGEs on plasma viscosity. PMID- 9371476 TI - Assessment of therapy in gestational diabetes by substrate and hormone responses to a standardized test meal. AB - Postprandial substrate and hormone responses to a standard mixed meal (400 kcal) was determined at two occasions, A and B, in 11 women with gestational diabetes (GDMs) and 11 normoglycaemic controls, matched for age, body mass index, and gestational age. Levels of circulating glucose, non-esterified fatty acids (NEFA), glycerol, 3-hydroxybutyrate (3-HBA), individual amino acids, insulin, and C-peptide were analysed. A was performed when GDMs were considered inadequately controlled with diet alone, B later during gestation following initiation of insulin therapy because of hyperglycaemia. Fasting glucose, glycerol, total and individual amino acids (alanine, valine, isoleucine, leucine), insulin, and C peptide were not different from normal during A and B, neither were postprandial amino acid levels. During test A, GDMs had elevated fasting and postprandial 3 HBA (p < 0.001), greater postprandial rise of glucose (p < 0.001), elevated NEFA (p < 0.05), but normal and parallel decreases of NEFA and glycerol. Insulin and C peptide responses were delayed and prolonged. During B, GDMs had higher glucose response (p < 0.005), higher fasting 3-HBA (p < 0.02) but similar and parallel decreases of NEFA, glycerol, and 3-HBA as controls. The C-peptide response was not significantly different from normal; insulin response was higher (p < 0.05). In conclusion, the relative insulin deficiency characterizing GDMs, also when treated with insulin, is associated with selected defects in insulin action; mainly affecting glucoregulation, whereas suppression of lipolysis and proteolysis remain normal. PMID- 9371477 TI - Consistency of pupillary abnormality in children and adolescents with diabetes. AB - Repeat measurements on pupillary adaptation to darkness were performed in a cohort of 66 children and adolescents with insulin-dependent diabetes mellitus (IDDM) (initial age 6.9-17.0 years) after a mean interval of 3.5 years, using a portable pupillometer. While there was a close correlation between the results of the two studies (r = 0.94, p < 0.001), the pupillary dilatation, the ratio of the pupil diameter to the iris diameter % (PD%), had decreased significantly (61.5% vs 62.9%, p < 0.001) over these 3.5 years in children with diabetes. The same measurements were performed on 89 healthy control children in the first study and 66 in the reassessment period and PD% was not significantly different in the two control groups. Five children with diabetes identified as having abnormal pupillary dilatation in the first study were outside the normal range 3.5 years later. In addition 4 children in whom initial testing had been normal, showed abnormality at the time of the second study. None of these children had symptoms of autonomic neuropathy. These findings suggest that abnormality in pupillary adaptation in diabetic children is consistent and increases with time and may serve as an early marker of tissue damage associated with diabetes. PMID- 9371475 TI - Lack of association of angiotensin II type 1 receptor gene polymorphism with diabetic nephropathy in insulin-dependent diabetes mellitus. AB - Several observations suggest that inherited factors are influential in the development of nephropathy in patients with insulin-dependent diabetes mellitus (IDDM). Genetic components of the renin angiotensin system are possible candidate genes. The aim of this study was to determine the role of the hypertension associated angiotensin II type 1 receptor (AT1R) gene A1166C polymorphism in susceptibility to nephropathy in IDDM. We examined 264 Caucasoid patients with IDDM and overt nephropathy (as defined by persistent proteinuria in the absence of other causes, hypertension and retinopathy), 136 IDDM patients with long duration of diabetes and no nephropathy (LDNN group), 200 recently diagnosed IDDM patients (Sporadic Diabetic group), and 212 non-diabetic subjects. The AT1R gene polymorphism was assessed using the polymerase chain reaction and restriction isotyping. Genotype frequencies did not differ significantly between the sporadic diabetic group and the nephropathy group (p = 0.245), nor between the long duration non-nephropathy group and the nephropathy group (p = 0.250). Allele frequencies were not significantly different between the three groups (p = 0.753). We conclude that there is no significant association between the hypertension associated AT1R gene polymorphism and diabetic nephropathy in patients with IDDM in the UK. PMID- 9371478 TI - Does the presence of diabetic nephropathy in parents influence the metabolic response in the offspring? AB - Non-insulin dependent (Type 2) diabetes mellitus (NIDDM) and long-term complications such as nephropathy have a strong genetic predisposition. Insulin resistance is thought to be a pathogenetic factor, predisposing genetically prone individuals to develop the microvascular complications of diabetes. To test these hypotheses, two groups of young individuals were studied: 28 offspring of parents having NIDDM and diabetic nephropathy (group 1) aged 29.5 +/- 6.1 years, BMI 25.2 +/- 4.7 kg m(-2) and 31 offspring of diabetic parents with no history of nephropathy, aged 31.6 +/- 4.1 years and BMI 26.3 +/- 4.9 kg m(-2) (group 2). All underwent a standard oral glucose tolerance test with measurement of serum insulin levels and serum lipid profile. Urine albumin:creatinine ratio (A/C ratio) and blood pressure were also recorded. Diabetes was detected in 2/28 (7.1%) and 3/31 (9.7%) and IGT was detected in 5/28 (25%) and 8/31 (25%) of groups 1 and 2, respectively. These differences were not statistically significant, but were higher than in a group of non-diabetic controls with healthy parents. Comparison of the normoglycaemic subjects (19 and 20 in group 1 and 2, respectively) showed no significant differences between blood pressure readings, fasting and 2 h plasma glucose, and lipid profiles. Plasma insulin values, fasting and 2 h, and the area under the graph were also similar in both groups, indicating an absence of higher insulin response in group 1 in comparison with group 2. These values were also not different from those in the non-diabetic controls. A delay in insulin response to glucose was noted in many of the offspring as indicated by a low deltaI/deltaG at 30'. We conclude that offspring of diabetic parents with nephropathy do not show higher risk of glucose intolerance or insulin resistance compared to those with diabetic parents without nephropathy. The relatively high plasma glucose values in the presence of normal insulin secretion in both groups of offspring of diabetic parents suggest the presence of insulin resistance. PMID- 9371479 TI - The development and progression of diabetic retinopathy in type I diabetic patients: a cohort study. AB - To describe the course and risk factors for development and progression of retinopathy, we studied a cohort of 333 Israeli Jewish patients with Type 1 (insulin-dependent) diabetes mellitus. The median age at diagnosis was 9.5 (range 0.04-26.2) years and the median duration of follow-up was 14 (range 1.6-30) years. Evaluation of both retinae was performed yearly since referral and HbA1 values were tested every 3 months since 1978. During a follow-up of 4070 patient years, 162 patients developed non-proliferative retinopathy. The median retinopathy-free interval was 14.9 years and after 30 years all patients were affected. Pre-pubertal duration of diabetes was relevant. Independent and significant risk factors for early onset of non-proliferative retinopathy were: poor cumulative glycaemic control (median retinopathy-free interval in the 1st vs 4th quartiles of mean HbA1 values over all years: 18.0 vs 12.5 years, p = 0.0001); onset of diabetes during or after puberty (median retinopathy-free interval in patients with onset of diabetes before, during or after pubescence: 16.3, 13.2 and 14.0 years, respectively, p = 0.0001); and non-Ashkenazi Jewish origin (median retinopathy-free interval 15.8 years in Ashkenazi vs 14.0 in non Ashkenazi patients, p = 0.0004). Of 162 patients with non-proliferative retinopathy, progression to proliferative retinopathy occurred in 37, during 707 patient-years. The first event of proliferative retinopathy was diagnosed within the 1st year after non-proliferative retinopathy evolved, and at 6.3 years since onset of non-proliferative retinopathy 75% of the patients were still free of proliferative changes. Risk factors significantly and independently associated with an early progression to the proliferative stage were: poor glycaemic control in the last 3 years prior to the development of proliferative retinopathy and non Ashkenazi Jewish origin. All patients in the 4th quartile of HbA1 values were affected by proliferative retinopathy within 11.6 years after onset of non proliferative retinopathy. PMID- 9371480 TI - Factors contributing to the presentation of diabetic foot ulcers. AB - We have undertaken a prospective study of the presentation of all 669 ulcers seen in a specialist multidisciplinary foot clinic between 1 January 1993 and 1 August 1996, with particular reference to the factors which precipitated ulceration as well as to any delays in referral. Nearly two-thirds (61.3%) of all lesions were first detected by the patient or a relative, and the remainder by a healthcare professional. The median (range) time which elapsed between ulcer onset and first professional review was 4 (0-247) days, and the median time between first review and first referral to the specialist clinic was 15 (0-608) days. Significant delays were judged to have occurred in 39 instances. The most common precipitant of ulceration was rubbing from footwear, which was responsible for 138 (20.6%). Fifty-eight (8.7%) were the result of immobilization from other illness, and a further 24 were the consequence of surgery. Overall, professional factors contributed to the development or deterioration of 106 lesions (15.8% total). These results should form the basis of strategies designed to minimize the onset of ulceration in those known to be at risk: educational strategies need to be directed at professionals as much as at patients. PMID- 9371481 TI - Development and validation of the diabetes fear of injecting and self-testing questionnaire (D-FISQ): first findings. AB - To quantify the degree of fear of self-injecting insulin and self-testing of blood glucose in adult insulin-treated diabetic patients, the Diabetes Fear of Injecting and Self-testing Questionnaire (D-FISQ) was developed. The D-FISQ is a 30-item self-report questionnaire consisting of two subscales that measure Fear of Self-Injecting (FSI) and Fear of Self-Testing (FST). To test validity and internal consistency, the D-FISQ was administered to a sample of 266 insulin treated patients (Type 1 and Type 2); four diagnosed injection phobic insulin requiring diabetic patients also completed the D-FISQ. The minimal score was obtained on the subscales by 62% (FSI) and 57% (FST) of the population. The D FISQ demonstrated high internal consistency, with Cronbach's as of 0.94 (D-FISQ), 0.94 (FSI), and 0.90 (FST). Spearman rho between fear of self-injecting and fear of self-testing was 0.59 (p < 0.001), justifying two separate subscales. Construct validity was confirmed by a correlation of 0.44 with Spielbergers Trait Anxiety Inventory (Spearman rho, p < 0.001). FSI-scores from the injection phobic patients were all > or =95th percentile, while three scored > or =95% on FST, indicating discriminative validity. Results confirm homogeneity and validity of the D-FISQ and suggest usefulness of this instrument in both clinical practice and research. PMID- 9371482 TI - Linking a hospital diabetes database and the National Health Service Central Register: a way to establish accurate mortality and movement data. AB - We have established a records linkage between 'Diabeta' (the computerized clinical records system in the Diabetes Unit of St Thomas' Hospital) and the National Health Services Central Register (NHSCR) of the United Kingdom. Over 7000 diabetic patient records have been collected since 1973. Demographic data on all diabetic patients were retrieved and submitted to the NHSCR via a floppy disk. A matching system (automatic or manual) was used by the NHSCR to identify deceased patients and the most recent demographic data was provided on patients alive. This linkage resulted in an update of 91% of records in Diabeta. The findings of the update included: (1) 86% of diabetic patient's death had not been notified to the hospital and were not recorded on Diabeta. Mortality can now be assessed accurately as an outcome measure in our diabetic population. (2) Provision of the NHS number to Diabeta, as before it was not available on many patients seen in the hospital. The NHS number is a key patient identifier which can be used to exchange information within the NHS-wide network. (3) Diabetes was recorded as a cause of death in only 36% of death certificates. Analyses of death certificates alone must thus give poor information about mortality in diabetes. (4) Geographical location of patients on the database was updated, enabling tracing of patients for long-term studies and analyses of movement. PMID- 9371483 TI - Insulin-dependent diabetes mellitus presenting with ketoalkalosis in Rett syndrome. AB - A 9-year-old girl with Rett syndrome presented with typical symptoms of insulin dependent diabetes mellitus. Upon investigation she was found to have a primary respiratory alkalosis associated with diabetes ketoacidaemia. Once non-ketotic normoglycaemia was achieved her respiratory alkalosis persisted. This was felt to be due to an abnormal breathing pattern of hyperventilation punctuated by apnoeas which is associated with Rett syndrome. PMID- 9371484 TI - The formation of the Medical and Scientific Section of the British Diabetic Association. AB - James (Jim) Jackson was the first administrative secretary to the Medical and Scientific Section of the British Diabetic Association (BDA). He played an important part in the creation of the Section and its development, bringing order into what had been rather haphazard medical meetings of the Diabetic Association. He has written this history of the Medical and Scientific Section of the BDA, based upon personal recollection with historical data taken from minutes of meetings. He writes: 'The Medical and Scientific Section emerged from a feeling of dissatisfaction among diabetologists and research workers about the post-war activities and aims of the Medical Advisory and Research Grant Committees of the British Diabetic Association. There was also a perceived need to involve physicians in charge of diabetic clinics countrywide more closely in the activities of the Association as a means of increasing its lay membership. This history is based upon personal recollection, with historical data taken from minutes of meetings'. Jim Jackson's history is accompanied by footnotes provided by Dr David Pyke (DAP), former physician in charge of the diabetes service at King's College Hospital, London, and onetime registrar of the Royal College of Physicians of London. PMID- 9371485 TI - Evaluation of a structured 4-day educational programme for intensive insulin therapy. PMID- 9371486 TI - Admission plasma glucose. PMID- 9371487 TI - Mortality rates in diabetic patients from a community-based population. PMID- 9371488 TI - Dissociation between steroid receptor expression and cell proliferation in the human breast. AB - We have shown previously that estradiol stimulates cell proliferation and progesterone receptor (PgR) synthesis in luminal epithelial cells of the normal human breast. Approximately 10-15% of luminal epithelial cells within the normal breast express immunodetectable estrogen receptor (ER), but little is known about their distribution within lobules and their organization in relation to the smaller population of proliferating cells. Using normal human breast tissue, we show that ER-positive cells are distributed evenly throughout the mammary epithelium. Using double antibody immunofluorescence, we show that 96% of steroid receptor-positive cells synthesize both ER and PgR (n = 25). Double labeling with antibodies to either ER or PgR coupled with either [3H]thymidine histoautoradiography or with antibodies to the Ki67 proliferation antigen indicates that dividing cells are separate from those expressing the receptors (although they are often in close proximity). However, in contrast to the normal human breast, two-thirds of ER-positive human mammary tumors examined (n = 19) have a high proportion of dividing cells that are ER positive. These data are consistent with the hypothesis that cells in normal human breast epithelium are hierarchical in organization and support a model in which proliferation of ER negative cells is controlled by paracrine factors released from ER-positive cells under the influence of estradiol. This organization may be disrupted in some tumors. PMID- 9371489 TI - Progressive decrease in nuclear retinoic acid receptor beta messenger RNA level during breast carcinogenesis. AB - Some of the nuclear retinoic acid receptors (RARs) alpha, beta, and gamma and retinoid X receptors (RXRs) alpha, beta, and gamma are thought to mediate the effects of retinoids on cell growth, differentiation, and apoptosis and thereby prevent breast carcinogenesis. We analyzed the expression of mRNAs for the three RARs and RXR-alpha in histological sections of specimens from 70 breast cancer patients, which included adjacent normal tissue, ductal carcinoma in situ, and invasive cancer, using in situ hybridization. RARs alpha, beta, and gamma and RXR alpha were expressed in 98.1, 98.0, 93.0, and 100% of the adjacent normal tissues. Significant decreases in the number of cases expressing RAR-beta were observed among ductal carcinoma in situ (83.1%) and invasive carcinomas (51.6%), especially among the poorly differentiated cases (77.4 and 35.7 %, respectively). No relationship was found between the expression of estrogen receptor and RAR beta. These results implicate decreases in RAR-beta expression in breast cancer development and suggest that they are independent of estrogen receptor status. PMID- 9371490 TI - Frequent inactivation of PTEN/MMAC1 in primary prostate cancer. AB - Sporadic prostate carcinoma is the most common male cancer in the Western world, yet many of the major genetic events involved in the progression of this often fatal cancer remain to be elucidated. Numerous cytogenetic and allelotype studies have reported frequent loss of heterozygosity on chromosomal arm 10q in sporadic prostate cancer. Deletion mapping studies have unambiguously identified a region of chromosome 10q23 to be the minimal area of loss. A new tumor suppressor gene, PTEN/MMAC1, was isolated recently at this region of chromosome 10q23 and found to be inactivated by mutation in three prostate cancer cell lines. We screened 80 prostate tumors by microsatellite analysis and found chromosome 10q23 to be deleted in 23 cases. We then proceeded with sequence analysis of the entire PTEN/MMAC1 coding region and tested for homozygous deletion with new intragenic markers in these 23 cases with 10q23 loss of heterozygosity. The identification of the second mutational event in 10 (43%) tumors establishes PTEN/MMAC1 as a main inactivation target of 10q loss in sporadic prostate cancer. PMID- 9371491 TI - Myeloperoxidase genetic polymorphism and lung cancer risk. AB - Myeloperoxidase is a lysosomal enzyme found in high concentrations in human lung due to recruitment of neutrophils. Myeloperoxidase activates benzo[a]pyrene as well as aromatic amines in tobacco smoke and generates carcinogen-free radicals. A single base substitution (G to A) in the promoter region of the myeloperoxidase gene has recently been demonstrated to markedly reduce transcription. We developed an RFLP/PCR assay to test the hypothesis that the allele favoring lower transcription (A allele) reduces the risk of lung cancer. Among population controls, 7.8% of 459 Caucasians and 9.4% of 244 African-Americans inherited two copies of the A allele. Caucasians with the A/A genotype were at 70% reduced risk of lung cancer (odds ratio, 0.30; 95% confidence interval, 0.10-0.93; P = 0.04; 182 cases). A lesser reduction in risk was observed for African-Americans with this genotype (odds ratio, 0.61; 95% confidence interval, 0.26-1.41; 157 cases). Individuals who inherit two copies of an allele that reduces transcription of the myeloperoxidase gene may be at decreased risk of lung cancer. PMID- 9371492 TI - Down-regulation of topoisomerase IIalpha in CEM cells selected for merbarone resistance is associated with reduced expression of Sp3. AB - DNA topoisomerase II (topo II) is a target for many clinically useful anticancer drugs. However, a major concern in the use of these drugs is the development of resistance, often manifested by reduced drug accumulation or reduced topo IIalpha activity, due to mutant enzyme or the enzyme's decreased expression. To date, little is known of how the topo IIalpha is down-regulated in the resistant cells. In this study, using CEM cells selected for resistance to merbarone, we found that topo IIalpha RNA levels were reduced, compared to the parental cells, and this corresponded to reduced protein levels, whereas there was no significant difference in the RNA stability among these cell lines. Furthermore, we detected a lower level of topo IIalpha promoter activity in these resistant cells compared to the drug-sensitive parents. Thus, the down-regulation of topo IIalpha appeared to occur at the transcriptional level. Nucleotide sequencing of the topo IIalpha promoter regions up to -1200 bp revealed no mutations, suggesting that some trans acting factors are possibly involved in this down-regulation of topo Ilalpha. In this context, we found by Northern blot analysis that the transcription factor, sp3, was reduced in the drug-resistant cell lines compared to the parental cells. Furthermore, cotransfection experiments revealed that Sp3 induced topo IIalpha promoter activity in a dose-dependent manner in drug-sensitive CEM cells, but its induction of topo IIalpha promoter activity was attenuated in the resistant B12 cells. Our results suggest that down-regulation of Sp3 might contribute to the reduced expression of topo IIalpha in certain drug-resistant tumor cells. PMID- 9371493 TI - Loss of heterozygosity studies and deletion mapping identify two putative chromosome 14q tumor suppressor loci in renal oncocytomas. AB - Renal oncocytoma is considered to be a benign tumor that shares some phenotypic features with chromophobe renal cell carcinoma (RCC). Recently, we described high frequencies of allelic loss at 1p, 2p, 6p, 10p, 13q, 14q, 17p, and 21q, which correlate significantly with the chromophobe subtype of RCC. To investigate the genetic relationship between these two entities, we examined 12 oncocytomas for loss of heterozygosity (LOH) at these regions. In addition, we included markers for 3p, 5q, 7q, 11p, and 22q. The only chromosomal region showing similarly high frequencies of allelic loss for both subtypes was 14q. Therefore, a genetic relationship between renal oncocytoma and chromophobe RCC seems questionable. Eight of 12 oncocytomas (67%) showed LOH at 14q, a frequency that was significantly higher (P < 0.001, chi(2) test) than the frequencies of LOH in all other regions. To define regions potentially harboring novel tumor suppressor genes, we performed multifluorescence microsatellite analysis with 13 markers spanning 14q. Interstitial deletions at different regions of 14q were detected, with the highest frequencies at D14S258 (14q23-24.3) and D14S292 (14q32.1-32.2). 14q LOH might be associated with advanced-stage RCCs or other tumors, but it does not seem to indicate progression in oncocytomas. Its role in pathogenesis of renal oncocytomas remains to be clarified. Here, we provide evidence for two distinct tumor suppressor gene loci at 14q in renal oncocytoma, which will be useful for further fine-mapping studies of these critical regions. PMID- 9371494 TI - Mdm-2 phosphorylation by DNA-dependent protein kinase prevents interaction with p53. AB - In response to genotoxic stress, the p53 tumor suppressor protein exerts a G1 cell cycle arrest that is dependent on its ability to transactivate downstream target genes. This p53-dependent G1 block is reversed by the binding of Mdm-2 to p53, preventing further transactivation. Interestingly, following DNA damage, the mdm-2 gene is also transcriptionally activated by p53, and therefore, the question of how p53 can continue to transactivate genes in the presence of its own negative regulator has remained unanswered. Here, we provide evidence that phosphorylation of Mdm-2 protein by DNA-dependent protein kinase (DNA-PK) blocks its ability to associate with p53 and regulate p53 transactivation. The data support a model by which DNA-PK activation by DNA damage and phosphorylation of Mdm-2 renders the Mdm-2 protein unable to inhibit p53 transactivation, resulting in cell cycle arrest. Following DNA repair, the loss of DNA-PK activity results in newly synthesized Mdm-2 protein that is unphosphorylated and, therefore, capable of binding to p53, allowing cell cycle progression. PMID- 9371495 TI - Exclusion of PTEN and 10q22-24 as the susceptibility locus for juvenile polyposis syndrome. AB - Juvenile polyposis syndrome (JPS; MIM 174900) is an autosomal dominant condition with incomplete penetrance characterized by hamartomatous polyps of the gastrointestinal tract and a risk of gastrointestinal cancer. Gastrointestinal hamartomatous polyps are also present in Cowden syndrome (CS; MIM 158350) and Bannayan-Zonana syndrome (BZS; also called Ruvalcaba-Myhre-Smith syndrome; MIM 153480). The susceptibility locus for both CS and BZS has recently been identified as the novel tumor suppressor gene PTEN, encoding a dual specificity phosphatase, located at 10q23.3. A putative JPS locus, JP1, which most likely functions as a tumor suppressor, had previously been mapped to 10q22-24 in both familial and sporadic juvenile polyps. Given the shared clinical features of gastrointestinal hamartomatous polyps among the three syndromes and the coincident mapping of JP1 to the region of PTEN, we sought to determine whether JPS was allelic to CS and BZS by mutation analysis of PTEN and linkage approaches. Microsatellite markers spanning the CS/BZS locus (D10S219, D10S551, D10S579, and D10S541) were used to compute multipoint lod scores in eight informative families with JPS. Lod scores of < -2.0 were generated for the entire region, thus excluding PTEN and any genes within the flanking 20-cM interval as candidate loci for familial JPS under our statistical models. In addition, analysis of PTEN using a combination of denaturing gradient gel electrophoresis and direct sequencing was unable to identify a germline mutation in 14 families with JPS and 11 sporadic cases. Therefore, at least a proportion of JPS cases are not caused by germline PTEN alteration or by an alternative locus at 10q22-24. PMID- 9371496 TI - Growth regulation of human prostate cancer cells by bone morphogenetic protein-2. AB - Bone morphogenetic proteins (BMPs) belong to the transforming growth factor-beta (TGF-beta) family and have been identified as factors that stimulate bone formation in vivo. They turned out to be multifunctional molecules regulating the growth, differentiation, and apoptosis in various target cells. Some BMPs and their receptors (BMPRs) are expressed on prostate cancer cells. We have reported previously that BMPR-IB mRNA expression is highest in the prostate, a characteristic that is not shared by the other BMPRs, BMPR-IA and BMPR-II. However, the amounts of BMPR-IB mRNA were significantly low in prostate tissues after androgen withdrawal therapy. They were also low in prostate cancer cell lines. Semiquantitative RT-PCR showed that BMPR-IB mRNA was induced by androgen in the androgen-sensitive human prostatic cancer cell line LNCaP, whereas the expression of BMPR-IA and BMPR-II mRNAs was not affected by androgen. When the recombinant human BMP-2 was added to the LNCaP cells in the presence of androgen, cell growth was inhibited. In contrast, the growth rate was increased by the addition of the same ligand when the cells were cultured in the absence of androgen; under this condition, the amounts of BMPR-IB mRNA were decreased significantly. These observations showed that the amounts of BMPR-IB, but not those of BMPR-IA, were regulated by androgen and further suggest that BMPR-IA and BMPR-IB differentially modulate prostate cancer cell growth in response to BMP under different hormonal conditions; BMPR-IA elicits growth stimulation, and BMPR IB conveys a negative regulatory signal in response to BMP-2. PMID- 9371497 TI - Tyrosine phosphorylation mediates ConA-induced membrane type 1-matrix metalloproteinase expression and matrix metalloproteinase-2 activation in MDA-MB 231 human breast carcinoma cells. AB - ConA-induced cell surface activation of pro-matrix metalloproteinase-2 (pro-MMP 2) by MDA-MB-231 human breast cancer cells is apparently mediated by up regulation of membrane type 1 MMP (MT1-MMP) through transcriptional and posttranscriptional mechanisms. Here, we have explored the respective roles of cell surface clustering and protein tyrosine phosphorylation in the ConA induction effects. Treatment with succinyl-ConA, a variant lacking significant clusterability, partially stimulated MT1-MMP mRNA and protein levels but did not induce MMP-2 activation, suggesting that clustering contributes to the transcriptional regulation by ConA but appears to be critical for the nontranscriptional component. We further found that genistein, an inhibitor of tyrosine phosphorylation, blocked ConA-induced pro-MMP-2 activation and ConA induced MT1-MMP mRNA level in a dose-dependent manner, implicating tyrosine phosphorylation in the transcriptional aspect. This was confirmed by the dose dependent promotion of pro-MMP-2 activation by sodium orthovanadate in the presence of suboptimal concentrations of ConA (7.5 microg/ml), with optimal effects seen at 25 microg/ml orthovanadate. Genistein did not inhibit the ConA potentiation of MMP-2 activation in MCF-7 cells, in which transfected MT1-MMP is driven by a heterologous promoter, supporting the major implication of phosphotyrosine in the transcriptional component of ConA regulation. These data describe a major signaling event upstream of MT1-MMP induction by ConA and set the stage for further analysis of the nontranscriptional component. PMID- 9371498 TI - Measurement of tumor cell cohesion and suppression of invasion by E- or P cadherin. AB - Invasiveness of carcinomas was connected early to decreased cohesiveness and has more recently been associated with loss or decreased activity of E-cadherin. In the first thermodynamic measurements of cohesive intensities among malignant cells, we here find the cohesive intensities of Lewis lung carcinoma cells to fall within the range measured previously for cells from a series of noninvasive embryonic tissues. Thus, too-low cohesiveness is itself an insufficient explanation for invasiveness. Nevertheless, transfection-mediated cadherin expression sufficient to increase cohesiveness by as little as 26% suffices to greatly reduce invasion of aggregates of Lewis lung carcinoma cells into Matrigel. This property is not restricted to E-cadherin but is shared by P cadherin. The same cadherin-transfected cells do not display this invasion suppression when plated sparsely, indicating that invasion-suppression activity of cadherins requires cell-cell contact. These facts are consistent with the invasion-suppression activity of cadherins resulting either from the physical restraint of increased cohesion per se or from another cadherin activity mediated through cell-cell contact. PMID- 9371499 TI - Serum thrombopoietin levels in patients receiving high-dose chemotherapy with support of purified peripheral blood CD34+ cells. AB - In a case control study, serum levels of thrombopoietin (TPO) were determined by a sandwich ELISA in 20 patients (median age, 7 years; range, 2-56 years) with various malignancies who received high-dose chemotherapy and a stem cell rescue operation. The patients received two different transplant modalities: (a) 12 patients received purified autologous peripheral blood CD34+ cells; and (b) 8 patients received cells in the CD34(-) fraction, which still contains many CD34+ cells. No significant differences were observed between the two groups with regard to the duration required to achieve an absolute granulocyte count of >0.5 x 10(9)/liter, the duration of dependence on platelet transfusion, or the number of platelet transfusions. In both groups, the serum TPO levels were inversely correlated with the circulating platelet count. Multivariate analysis demonstrated that significant determinants of the serum TPO level included the circulating platelet count (standardized regression coefficient = -0.5179), transplantation with cells in the CD34(-) fraction (0.2414), solid tumor (0.1420), and the age of the patient (-0.1236; r2 = 0.3021; P < 0.0001). These results suggest that the mode of stem cell support (ie., the presence of accessory cells in the inoculum), age, or the type of preceding chemotherapy affects serum TPO levels after transplantation. PMID- 9371500 TI - Malignant transformation by overproduction of translation initiation factor eIF4G. AB - N4G3, a cell line that overexpresses translation initiation factor eIF4G, one of the components of eIF4F, was made by stable transfection of the human eIF4G cDNA into NIH3T3 cells. The cells expressed 80-100 times greater levels of eIF4G mRNA than did NIH3T3 cells. N4G3 cells formed transformed foci on a monolayer of cells, showed anchorage-independent growth, and formed tumors in nude mice. These results indicate that overexpression of eIF4G caused malignant transformation of NIH3T3 cells. It is also known that overexpression of eIF4E, another component of eIF4F, causes transformation of NIH3T3 cells. However, there was no difference in the amount of eIF4E protein between N4G3 and NIH3T3 cells, indicating that cell transformation does not involve a change in eIF4E levels. The results may be due to an effect of eIF4G on translational control of protein synthesis directed by mRNAs having long 5'-untranslated region. PMID- 9371501 TI - Apc gene mutation is associated with a dominant-negative effect upon intestinal cell migration. AB - Apc-associated intestinal tumor formation appears to require functional loss of both Apc alleles. Apc has, therefore, been classified as a tumor suppressor gene. Loss of APC protein function results in increased intracellular beta-catenin, a molecule important to both cell-cell adhesion and regulation of cellular growth. In mice bearing a germ-line Apc mutation, we found that enterocyte beta-catenin expression was also increased in histologically normal intestinal mucosa. Enterocyte crypt-villus migration was decreased by 25%, and treatment of Min/+ animals with sulindac sulfide normalized both beta-catenin expression and enterocyte migration. Our data suggest that alterations in enterocyte migration occur in cells bearing a single mutant Apc allele, and that sulindac sulfide may normalize enterocyte growth in these cells. PMID- 9371502 TI - Sodium arsenite disturbs mitosis and induces chromosome loss in human fibroblasts. AB - Arsenite, a unique human carcinogen, induces many types of cytogenetic alterations, such as sister chromatid exchanges, chromosome aberrations, and endoreduplication in a variety of in vivo and in vitro systems. Cytogenetic alterations are frequently associated with cancer development. The purpose of this study was to explore how arsenite induces cytogenetic alterations in human skin fibroblasts (HFW). The present results show that treatment of G2-enriched HFW cells with 5 microM arsenite results in significant delay of cell cycle progression, accumulation of mitotic cells, and prolongation of mitosis. Arsenite induced G2 and mitotic delay are accompanied by accumulation of cyclin B1 and hyperphosphorylation of cdc2 and Mos proteins. In addition to mitotic delay and prolongation, arsenite treatment also induced out-of-phase centromere separation and alterations of chromosome segregation, such as the appearance of c-metaphase, ball-metaphase, and lagged chromosomes. Unlike spindle poisons, arsenite at the dose range used did not inhibit the spindle fiber formation but conceivably deranges the spindle apparatus. By analyzing the karyotype of established subclones surviving arsenite injury, 18% (8 of 44) showed one chromosome loss, whereas all 26 subclones derived from the untreated cultures were diploid. Furthermore, most arsenite-treated clones manifest prolonged life span (86 +/- 18 population doublings) as compared to those derived from the untreated cultures (44 +/- 11 population doublings). Unfortunately, none became immortal. Collectively, treatment of the G2-enriched HFW cells with arsenite can disturb the mitotic events and subsequently induce chromosome loss. PMID- 9371503 TI - Induction of activating transcription factor 1 by nickel and its role as a negative regulator of thrombospondin I gene expression. AB - Thrombospondin I (TSP I) is an extracellular matrix glycoprotein that influences cell adhesion, motility, and growth. On the basis of its effects on endothelial cell proliferation, TSP I has attracted interest as a potential regulator of solid tumor growth through modulation of tumor blood supply. The regulation of TSP I expression is of critical importance for designing new approaches in tumor therapy. Recently, we have shown that TSP I expression is lost in nickel transformed cells. In this paper, we identified an activating transcription factor (ATF)/cAMP-responsive element-binding protein binding site as a negative regulatory site in the 5'-flanking sequence of mouse TSP I promoter. We identified ATF-1 as a major component of the ATF/cAMP-responsive element-binding protein binding complex. This Mr 35,000 nuclear ATF-1 protein was shown to be present in higher amounts in nickel-transformed 3T3 cells that do not express TSP 1. Acute treatment of 3T3 cells with NiCl2 resulted in the induction of this transcription factor, and this induction was correlated temporally with the suppression of TSP I expression in the same cells. These results show that nickel exposure causes accumulation of the ATF-1 transcription factor, which is responsible for the down-regulation of transcription of TSP I, and possibly other tumor suppressor genes during nickel-induced cellular transformation. PMID- 9371504 TI - Morphological and biochemical status of the mammary gland as influenced by conjugated linoleic acid: implication for a reduction in mammary cancer risk. AB - Previous research showed that treatment with conjugated linoleic acid (CLA) during the period of active mammary gland morphogenesis was sufficient to confer a lasting protection against subsequent mammary tumorigenesis induced by methylnitrosourea. The present study was designed to characterize certain morphological and biochemical changes of the mammary gland that might potentially render it less susceptible to cancer induction. Female Sprague Dawley rats were fed a 1% CLA diet from weaning until about 50 days of age. The mammary gland parameters under investigation included (a) the deposition of neutral lipid, (b) the identification and quantification of CLA and its metabolites, (c) the density of the epithelium, and (d) the proliferative activity of various structural components. Our results showed that CLA treatment did not affect total fat deposition in the mammary tissue nor the extent of epithelial invasion into the surrounding fat pad but was able to cause a 20% reduction in the density of the ductal-lobular tree as determined by digitized image analysis of the whole mounts. This was accompanied by a suppression of bromodeoxyuridine labeling in the terminal end buds and lobuloalveolar buds. The recovery of desaturation and elongation products of CLA in the mammary gland confirmed our prior suggestion that the metabolism of CLA might be critical to risk modulation. The significance of the above findings was investigated in a mammary carcinogenesis bioassay with the use of the dimethylbenz[a]anthracene model. When CLA was started at weaning and continued for 6 months until the end of the experiment, this schedule of supplementation produced essentially the same magnitude of mammary tumor inhibition in the dimethylbenz[a]anthracene model as that produced by 1 month of CLA feeding from weaning. The observation is consistent with the hypothesis that exposure to CLA during the time of mammary gland maturation may modify the developmental potential of a subset of target cells that are normally susceptible to carcinogen-induced transformation. PMID- 9371505 TI - Prognostic value of serum 5-S-cysteinyldopa for monitoring human metastatic melanoma during immunochemotherapy. AB - The melanin metabolite 5-S-cysteinyldopa (5-S-CD) has been reported to be helpful in detecting occult melanoma metastases and as a prognostic marker in B16 melanoma-bearing mice. The goal of our study was to analyze the significance of the serum 5-S-CD level for the biochemical detection of metastases in human malignant melanoma (MM) and for monitoring the progression or the immunochemotherapeutically induced regression of MM. From 11 patients with metastatic MM observed between 1991 and 1995, serum samples were collected before and after each cycle of immunotherapy or immunochemotherapy. Samples were analyzed for 5-S-CD by automated high performance liquid chromatography with electrochemical detection. Cycles of immunochemotherapy consisted of human interleukin 2 and IFN-alpha (four patients) or of human interleukin 2, IFN-alpha, and dacarbazine (seven patients). Serum value of 5-S-CD in our normal controls was 1.9 +/- 0.6 ng/ml. All patients with metastatic MM showed 5-S-CD serum levels above the upper normal limit of 3.2 ng/ml (10 nM) and ranged from 2.3-fold (4.3 +/- 3.9 ng/ml) of the normal control values in early stages of metastases to more than 50-fold (94.3 +/- 220.3 ng/ml) of the normal control values in advanced stages of the disease. In 28 of 41 (68%) immunochemotherapeutical cycles, a decrease of 5-S-CD was seen during therapy, and in 13 cycles (31.7%), an increase was seen. Patients with more than 68% decreasing cycles (defined as responders; n = 5) showed significantly longer survival times (P = 0.008) than patients with less than 68% decreasing cycles (nonresponders; n = 6). High levels of 5-S-CD were also observed in metastasizing amelanotic melanoma. Serum 5-S-CD is a useful marker for monitoring the clinical course of MM patients, for discriminating between responders and nonresponders to immunochemotherapy, and as a prognostic factor concerning survival time and death risk. PMID- 9371506 TI - Diet, body size, physical activity, and the risk of endometrial cancer. AB - Endometrial cancer is associated with increased weight and body size, diabetes, and other conditions that may result from an excess in calories or lack of physical activity. Although a few studies have explored the effect of dietary constituents on the risk of endometrial cancer, the nature of the joint association of these constituents and obesity, energy intake, or energy expenditure with risk is unknown. A population-based case-control study was conducted in Hawaii to examine the association of diet, body size, and physical activity with the risk of endometrial cancer. Subjects included 332 histologically confirmed, primary endometrial cancer cases and 511 controls identified between 1985 and 1993. Cases and controls were residents of Oahu, Hawaii who were between 18 and 84 years of age and were from one of the following ethnic groups: Japanese, Caucasian, Native Hawaiian, Filipino, and Chinese. Cases were identified through the Hawaii Tumor Registry and matched to the controls on age (+/-2.5 years) and ethnicity. In-person interviews, conducted in the subjects' homes, included dietary, reproductive, menstrual, and medical histories and use of exogenous hormones, physical activity, and other lifestyle variables. Weight, girth, and skinfold measurements were taken at the time of the interview. We found a strong dose-response relation of increased body size to the development of endometrial cancer after adjustment for energy intake. The odds ratio (OR) for endometrial cancer among women in the highest quartile of body mass index (BMI; kg/m2) was more than four times that among women in the lowest quartile. Waist, hip, midarm, and wrist girths were positively associated with the estimated risk of endometrial cancer after adjustment for total calories and other nondietary risk factors, although the trends in the ORs were attenuated after adjustment for BMI. Physically active women had a modest reduction in their risk of disease compared with inactive women. Cases consumed a greater percentage of their calories from fat and a lower percentage of their calories from carbohydrates than did controls. Adjustment for BMI reduced the ORs for the highest compared with the lowest quartile of fat calorie intake from 2.0 (95% confidence interval, 1.3-3.2) to 1.6 (95% confidence interval, 1.0-2.6), suggesting that part of the association is explained by obesity. There was a differential effect of fat on endometrial cancer according to BMI. For all components of fat, the associations with endometrial cancer were either minimal or absent among leaner women (i.e., those with BMI below the median), whereas, among more obese women, two-fold differences in risk were observed between women above and below the median of fat intake. Foods that are high in fat and cholesterol, such as red meat, margarine, and eggs, were positively associated with endometrial cancer, whereas cereals, legumes, vegetables, and fruits, particularly those high in lutein, were inversely associated. These findings suggest that women who avoid being overweight and who consume a diet low in plant and animal fats and high in complex carbohydrates are at a reduced risk of endometrial cancer. PMID- 9371507 TI - Cellular adaptation to drug exposure: evolution of the drug-resistant phenotype. AB - The efficacy of all chemotherapeutic agents is limited by the occurrence of drug resistance. For etoposide (VP-16), increased expression of MDR-1 or MRP and alterations in topoisomerase IIalpha have been shown to confer tolerance. To further understand resistance to VP-16, three sublines, designated MCF-7-VP17, ZR 75B-VP13, and MDA-MB-231-VP7, were initially isolated as single clones from parental cells by exposure to VP-16. Subsequently, a population of cells from each subline was exposed to 3-fold higher drug concentrations, allowing stable sublines to be established at higher extracellular drug concentrations. Characterization of the resistant sublines demonstrates the adaptation that occurs with advancing drug concentrations during in vitro selections. Reduced topoisomerase II mRNA and protein levels were observed in the initial isolates. This reduction was accompanied by a decrease in topoisomerase II activity and cellular growth rate and was associated with 6-314-fold resistance to topoisomerase II poisons. With advancing resistance, MRP expression increased and VP-16 accumulation decreased. This adaptation allowed for partial restoration of topoisomerase II activity as a result of increased expression (MCF-7-VP17 and ZR 75B-VP13) or hyperphosphorylation (MDA-MB-231-VP7), with a resultant increase in growth rate. In MDA-MB-231-VP7 cells, hyperphosphorylation coincided with increased casein kinase II mRNA and protein levels, suggesting a role for this kinase in the acquired hyperphosphorylation. In this cell line, hyperphosphorylation mediated the increased activity despite a fall in topoisomerase IIalpha protein levels secondary to an acquired 600-bp deletion in one topoisomerase IIalpha allele, which resulted in reduced protein levels. In all three sublines, high levels of resistance were attained as a result of synergism between the reduced topoisomerase IIalpha levels and MRP overexpression. These studies demonstrate how cellular adaptation to increasing drug pressure occurs and how more than one mechanism can contribute to the resistant phenotype when increasing selecting pressure is applied. Reduced expression of topoisomerase II is sufficient to confer substantial resistance early in the selection process, with synergy from MRP overexpression helping to confer high levels of resistance. PMID- 9371508 TI - Selection for G156A O6-methylguanine DNA methyltransferase gene-transduced hematopoietic progenitors and protection from lethality in mice treated with O6 benzylguanine and 1,3-bis(2-chloroethyl)-1-nitrosourea. AB - A retroviral gene therapy approach was developed to protect early hematopoietic progenitors from 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), a stem cell toxin, and O6-benzylguanine (BG), an inhibitor of a key BCNU resistance protein, O6 alkylguanine DNA alkyltransferase (AGT). The retroviral vector MFG was used to transfer the G156A MGMT (deltaMGMT) cDNA, encoding a mutant AGT that is resistant to inhibition by BG, into murine bone marrow-derived hematopoietic progenitors. Following transplantation into lethally irradiated mice, the transduced cells were subjected to in vivo BG and BCNU treatment to examine the ability to enrich for transduced cells expressing deltaAGT. Transplantation of deltaMGMT-transduced cells resulted in deltaAGT expression in 30% of bone marrow nucleated cells 13 weeks after transplantation. After one cycle of BG and BCNU, deltaAGT expression was observed in 60% of bone marrow cells, and the percentage of colony-forming units (culture; CFU-C) containing proviral sequence increased from 67 to 100%. CFU-C obtained from BG and BCNU-treated deltaMGMT animals up to 23 weeks after transplantation were more resistant to combination BG and BCNU than CFU-C from mice transplanted with lacZ-transduced cells and treated with BG and BCNU or from mice transplanted with deltaMGMT-transduced cells and left untreated. The degree of drug resistance in deltaMGMT-transduced hematopoietic progenitors to BG and BCNU was much greater than we observed previously with wild-type MGMT gene transfer and treatment with BCNU alone. Furthermore, whereas 21 of 22 mice transplanted with deltaMGMT-transduced cells survived in vivo BG and BCNU administration, only 3 of 13 mice transplanted with lacZ-transduced progenitors survived similar drug treatment. Thus, deltaMGMT-transduced murine bone marrow cells selectively survive in vivo BG and BCNU exposure, resulting in prolonged enrichment for the transduced cells and protection from mortality induced by this drug combination. PMID- 9371509 TI - Mechanisms of resistance in a human cell line exposed to sequential topoisomerase poisoning. AB - Camptothecins are a new class of anticancer drugs that target DNA topoisomerase I; current efforts are directed toward elucidating optimal combinations of these drugs with other antineoplastic agents. A rationale for the use of sequential therapy involving the combination of camptothecins with topoisomerase II targeting drugs, such as etoposide, has arisen from observations of increased topoisomerase II protein levels in cell lines resistant to camptothecin. In an effort to understand potential mechanisms of resistance to this strategy, we developed a U-937 cell subline, denoted RERC, that is capable of surviving exposure to sequential topoisomerase poisoning. The RERC cells are 200-fold resistant to camptothecin, 8-fold resistant to etoposide, and 10-fold hypersensitive to cisplatin compared to the parental U-937 cells. Biochemical analyses indicate that the resistant phenotype involves alterations in both topoisomerase I and topoisomerase IIalpha. Topoisomerase I catalytic activity in the resistant cells is similar to that of the parental line but is resistant to camptothecin. Moreover, the resistant cells express a single mRNA species of topoisomerase I that codes for a mutation in codon 533. In addition, topoisomerase IIalpha protein levels are decreased 10-fold in the resistant line, coincident with a two-fold decrease in the expression of topoisomerase IIalpha mRNA. Collectively, these results indicate that resistance to sequential topoisomerase poisoning may involve a reduction in total cellular topoisomerase activity. PMID- 9371510 TI - Synergistic inhibition of growth and induction of apoptosis by 8-chloro-cAMP and paclitaxel or cisplatin in human cancer cells. AB - 8-Chloro-cAMP (8-Cl-cAMP) is a novel agent that is able to inhibit the growth of a wide variety of cancer cell types in vitro and in vivo and, at doses devoid of toxicity, to achieve plasma concentrations in cancer patients in a range effective for cancer cell growth inhibition. In this study, we have demonstrated that 8-Cl-cAMP, at a dose causing mild or no growth inhibition, synergistically increased the growth-inhibitory effect of paclitaxel or cisplatin in a wide series of cell lines including human breast, lung, ovary, colon, and head carcinomas and melanoma. A similar effect was also observed with another taxane, docetaxel, and with the platinum-derivative carboplatin. 8-Cl-cAMP also markedly enhanced apoptotic cell death induced by each cytotoxic drug. A cooperative antitumor effect was also observed in vivo, because treatment with paclitaxel followed by 8-Cl-cAMP markedly inhibited the growth of GEO human colon cancer xenografts as compared to paclitaxel alone without signs of toxicity. These data demonstrate that 8-Cl-cAMP synergistically increases the antiproliferative activity of taxanes and platinum-derived compounds and provide a rationale to use 8-Cl-cAMP in combination with taxanes and platinum-derived compounds. PMID- 9371511 TI - Hypersensitivity to DNA cross-linking agents associated with up-regulation of glucose-regulated stress protein GRP78. AB - We have shown previously that NAD/poly(ADP-ribose) polymerase-deficient cells that overexpress Mr 78,000 glucose-regulated stress protein (GRP78) are resistant to topoisomerase II inhibitors, such as etoposide, m-amsacrine, and doxorubicin. However, these cells have been found to be hypersensitive to DNA cross-linking agents, including melphalan, cisplatin, and 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). These observations prompted us to examine whether overexpression of GRP78 is associated with modulation of cytotoxicity of clinically useful DNA-cross linking agents such as melphalan, BCNU, and cisplatin. We up-regulated GRP78 in V79 Chinese hamster cells by 2-5-fold using two independent approaches that include exposure to 6-aminonicotinamide, or 2-deoxyglucose. Subsequently, these GRP78-overexpressing cells were trypsinized, plated in regular medium without GRP78-inducing agents, and allowed a 5-h attachment time before being treated with melphalan, BCNU, or cisplatin for 1 h to determine clonogenic survivals. In addition, repair of DNA cross-links induced by those agents were determined by alkaline elution assay. Our results show that the GRP78-overexpressing V79 cells are hypersensitive to DNA cross-linking agents compared to the control V79 cells. Furthermore, repair of drug-induced DNA cross-links appears to be considerably slower in these cells relative to that found in control V79 cells. Thus, our results suggest that (a) up-regulation of GRP78 is associated with an impairment of DNA cross-link repair, (b) up-regulation of GRP78 is associated with potentiation of cytotoxicity induced by alkylating and platinating agents, and (c) up-regulation of GRP78 can be considered as a potentially useful tool to modulate the cytotoxicity of clinically useful alkylating and platinating agents. PMID- 9371512 TI - CBP/cycA, a CCAAT-binding protein necessary for adhesion-dependent cyclin A transcription, consists of NF-Y and a novel Mr 115,000 subunit. AB - Cells of most tissues, with the exception of hematopoietic cells, require adhesion to an appropriate surface to grow. Cyclin A is needed for cell cycle progression at the G1-S transition, and appearance of cyclin A mRNA and protein in late G1 has been shown to be dependent on adhesion-initiated signals in normal rat kidney fibroblasts. Previously, we have reported that the adhesion-dependent activation of cyclin A transcription in late G1 is mediated by CBP/cycA (CCAAT binding protein for cyclin A gene), a novel CCAAT-binding protein. Specific binding of CBP/cycA, a Mr 30,000/40,000/115,000 heterotrimeric protein complex, to the CCAAT element of the cyclin A promoter was detectable in growing but not in G0-arrested or nonadherent normal rat kidney cells. Here, we demonstrate that the Mr 30,000/40,000 subunits of CBP/cycA are identical with NF-YA and NF-YB, the two subunits of NF-Y. In addition, we show that, aside from CBP/cycA, NF-Y itself also binds to the CCAAT element of the cyclin A promoter. But, whereas the binding of CBP/cycA is adhesion and cell cycle dependent and correlates with the expression of cyclin A in late G1 phase, NF-Y itself seems to bind in a cell cycle-independent manner. PMID- 9371513 TI - Clone 10d/BM28 (CDCL1), an early S-phase protein, is an important growth regulator of melanoma. AB - Retinoic acid (RA) induces growth arrest and differentiation of many different tumor cells. RA activates RA receptors, which function as ligand-dependent transcriptional modulators. S91 murine melanoma cells stop proliferating and then reversibly differentiate into a melanocytic cell type after the administration of RA. The genetic changes that take place during this process serve as an excellent model for the etiology of melanoma. The use of subtractive hybridization techniques yielded several differentially expressed cDNAs that are associated with RA-induced growth arrest. One clone, cyclin D1, is repressed and is probably a differentiation marker. Two other cDNAs represent novel, RA-inducible genes. Expression of another cDNA, clone 10d, is strongly down-regulated. It is the homologue of the human gene BM28 (CDCL1) that is indispensable for entry into S phase and cell division. S91 cells that are permanently transfected with a plasmid that constitutively expresses clone 10d become significantly more resistant to RA, suggesting that repression of this gene is a critical event in RA-induced growth arrest. The use of reverse transcription-PCR for the detection of expression in human melanoma in vitro was performed to study the potential role of clone 10d/BM28 in this disease. It is expressed in 80% of melanoma cell lines but is virtually undetectable in primary melanocytes. The expression of BM28 is not regulated by RA in human, RA-resistant melanoma cells. These results suggest that clone 10d/BM28 functions as an important tumor cell growth promoter. The regulation of clone 10d may be directly mediated by RA receptors, and escape from negative regulation may, thus, contribute to the etiology of melanoma. PMID- 9371514 TI - Transcriptional repression of the cyclin-dependent kinase inhibitor p21WAF1/CIP1 gene mediated by cis elements present in the 3'-untranslated region. AB - The cyclin-dependent kinase inhibitor p21WAF1/CIP1 plays a major role in the induction of G1 cell cycle arrest following DNA damage and is known to be regulated by p53-dependent and -independent pathways. Here, we show that p21WAF1/CIP1 transcription is also regulated, independently of p53, by the cis elements that are located downstream of the transcription start site. A cDNA fragment of approximately 180 bp, located 260 bases 3' to the translation termination codon of p21WAF1/CIP1 cDNA, was cloned in both the sense and antisense orientations downstream of the CMV promoter, upstream of the SV40 promoter, and both upstream and downstream of the p21WAF1/CIP1 promoter in the plasmids carrying the luciferase reporter gene. The constructs were transiently transfected in human breast carcinoma cells MCF-7 and MDA-MB-468 and a Syrian hamster smooth muscle cell line DDT1MF2 and were found to elicit 2-3-fold or higher repression of luciferase activities. By using overlapping deletions of the above 180-bp fragment, we identified a 48-bp subfragment that contains putative cis element(s) that participate in the transcriptional repression of the p21WAF1/CIP1 gene. The overlapping subfragments bind, in vitro, to specific proteins present in the nuclear extracts of MDA-MB-468 and DDT1MF2 cells. We, therefore, propose that additional mechanism(s) exist that regulate expression of the cellular p21WAF1/CIP1 and may contribute to p21WAF1/CIP1-dependent control of the cell cycle. PMID- 9371515 TI - The transactivation and p53-interacting functions of hepatitis B virus X protein are mutually interfering but distinct. AB - Transactivation of viral and host genes expression by hepatitis B virus X protein (HBx) is believed to be involved in hepatocarcinogenesis. The interaction of HBx with the tumor suppressor p53 and its inhibitory effect on p53 functions have been reported recently. However, the question of whether p53 is directly involved in HBx transactivation has not yet been addressed. In this study, we delineated the interaction sites of HBx and p53 using far-Western blotting and glutathione S transferase-resin pull-down assays. The results indicate that the HBx-binding sites are located within the oligomerization and specific DNA-binding domains of p53 and that the p53-binding site was confined to a small region in the HBx transactivation domain. Mutual interference of the transactivations by HBx and p53 was detected by CAT assays in a transient transfection system. Strikingly, transactivation by HBx was observed in the p53-negative cells, Saos-2 and Hep3B, indicating that the transactivation and the p53-inhibiting functions of HBx are mutually interfering but distinct. PMID- 9371516 TI - Role of DNA mismatch repair in the cytotoxicity of ionizing radiation. AB - The DNA mismatch repair (MMR) system in mammalian cells not only serves to correct base mispairs and other replication errors, but it also influences the cellular response to certain forms of DNA damage. Cells that are deficient in MMR are relatively resistant to alkylation damage because, in wild-type cells, the MMR system is thought to promote toxicity via futile repair of alkylated mispairs. Conversely, MMR-deficient cells are sensitive to UV light, possibly due to the requirement for MMR factors in transcription-coupled repair of active genes. MMR deficiency has been associated with familial and sporadic carcinomas of the colon and other sites, and so, we sought to determine the influence of MMR status on cellular response to ionizing radiation, an agent commonly used for cancer therapy. Fibroblast cell lines were established from transgenic mice carrying targeted disruptions of one of three MMR genes in mammalian cells: Pms2, Mlh1, or Msh2. In comparison to wild-type cell lines from related mice, the Pms2 , Mlh1-, or Msh2-nullizygous cell lines were found to exhibit higher levels of clonogenic survival following exposure to ionizing radiation. Because ionizing radiation generates a variety of lesions in DNA, the differences in survival may reflect a role for MMR in processing a subset of these lesions, such as damaged bases. These results both identify a new class of DNA-damaging agents whose effects are modulated by the MMR system and may help to elucidate pathways of radiation response in cancer cells. PMID- 9371517 TI - Heparin/heparan sulfate interacting protein expression and functions in human breast cancer cells and normal breast epithelia. AB - Heparin/heparan sulfate interacting protein (HIP) is a recently identified protein expressed by many normal epithelia and epithelial cell lines. In the present study, we examined expression and potential functions of this protein in a series of human breast cancer cells and in sections of normal and malignant human breast tissue. Four of the five breast cancer cell lines studied (MCF-7, T 47D, MDA-MB468, and BT-549) expressed HIP protein and mRNA at similar levels. In contrast, MDA-MB-231 cells failed to display reactivity with HIP-specific probes in any assay. Cell aggregation assays and cell surface antibody binding studies demonstrated that HIP was expressed on the cell surface. However, HIP expression did not correlate with the number of cell surface [3H]heparin (HP) binding sites. The K(Dapp)s for cell surface HP binding sites were similar in all breast cancer cell lines studied and ranged from 112 to 298 nM. In contrast, cell surface HP binding capacity varied greatly, ranging from 2.3 x 10(5) (MDA-MB-231 and MDA-MB 468) to 99 x 10(5) sites/cell (BT-549). All cell lines tested displayed the ability to bind to a heparan sulfate (HS)-binding synthetic peptide motif of HIP in a HP-inhibitable fashion. Binding to this motif was not inhibited by other glycosaminoglycans including hyaluronic acid, chondroitin sulfates, or keratan sulfate. Furthermore, cell binding to HIP peptide was almost completely lost when intact cells were predigested with heparinases but not chondroitinases. Cell surface HS from breast cancer cells as well as normal human breast epithelia binded to HIP peptide in a HP-inhibitable fashion, demonstrating the ability of these cell surface components to directly interact. HIP was detected in both normal breast epithelia and breast tumors in situ. It is suggested that HIP mediates aspects of HS-dependent interactions of both normal and malignant breast epithelia with other cells and extracellular matrix components. PMID- 9371518 TI - Tamoxifen induces hypoxia in MCF-7 xenografts. AB - Tamoxifen is widely used as an adjunct therapy for breast cancer. We hypothesized that hypoxia develops in tumors as a result of tamoxifen treatment because tamoxifen has been reported to be antiangiogenic and thrombogenic. MCF-7 breast tumors were grown under estrogenic stimulation in 4-6-week-old CD-1 nu/nu female mice. When the tumors were approximately 5 mm in diameter, 17beta-estradiol pellets were replaced with either placebo or tamoxifen-containing pellets. Two days later, tissue oxygenation was measured using immunohistochemical detection of binding of the 2-nitroimidazole EF5. Intravascular oxygen partial pressures were measured noninvasively by oxygen-dependent quenching of phosphorescence of an injected dye that is excited by light pulses. Tamoxifen treatment increased hypoxia in the tumors, as measured by EF5 binding (P = 0.01 by Mann-Whitney test). This observation was not dependent on the presence of tamoxifen-induced necrosis. Intravascular oxygen partial pressures were lower in tumors relative to surrounding normal tissue in tamoxifen-treated tumors as compared to placebo treated tumors. In vitro, tamoxifen did not modify the oxygen-dependent metabolism of EF5, indicating that the increased EF5 binding in tamoxifen-treated tumors reflects a physiological decrease in tissue oxygenation. The clinical significance of these observations is discussed in the context of the sequencing of tamoxifen with other therapies, and in light of recent data suggesting that hypoxia may be associated with genetic changes resulting in a more aggressive tumor phenotype. PMID- 9371519 TI - Thioredoxin, a gene found overexpressed in human cancer, inhibits apoptosis in vitro and in vivo. AB - The redox protein thioredoxin plays an important role in controlling cancer cell growth through regulation of DNA synthesis and transcription factor activity. Thioredoxin is overexpressed by a number of human primary cancers and its expression is decreased during dexamethasone-induced apoptosis of mouse WEHI7.2 thymoma cells. We examined the ability of WEHI7.2 cells stably transfected with human thioredoxin cDNA showing increased levels of cytoplasmic thioredoxin to undergo apoptosis in vitro and in vivo. The cells were protected from apoptosis induced by dexamethasone, staurosporine, etoposide, and thapsigargin, but not by N-acetyl-sphingosine. When inoculated into severe combined immunodeficient mice, the trx-transfected cells formed tumors that showed increased growth compared to wild-type, as well as bcl-2-transfected, WEHI7.2 cells. The trx- and bcl-2 transfected cell tumors both showed less spontaneous apoptosis than tumors formed by the wild-type cells. Unlike tumors formed by the wild-type and bcl-2 transfected WEHI7.2 cells, trx-transfected cell tumors did not show growth inhibition upon treatment with dexamethasone. This study suggests that increased thioredoxin expression in human cancers may result in an increased tumor growth through inhibition of spontaneous apoptosis and a decrease in the sensitivity of the tumor to drug-induced apoptosis. PMID- 9371520 TI - The role of Cdc2 feedback loop control in the DNA damage checkpoint in mammalian cells. AB - DNA damage inactivates cyclin-dependent kinases (CDKs) and arrests the cell cycle. Following DNA damage, the G1-S CDKs are inhibited by a mechanism involving p53-dependent induction of p21Cip1/Waf1; but how the Cdc2 is inhibited is less apparent. We found that the signal generated by the DNA damage checkpoint in G2 was dominant over that from the spindle microtubule-assembly checkpoint, because the high Cdc2 activity present in nocodazole or Taxol-arrested cells was reduced by DNA damage. Phosphorylation of the inhibitory residues in Cdc2, Thr14, and Tyr15 coincided with the inactivation of Cdc2 after DNA damage. Interpretation of this result, however, was not straightforward due to the regulation of Thr14/Tyr15 phosphorylation by feedback loops; hence, their phosphorylation can in principle result merely from the inhibition of Cdc2 activity. Consistent with this, Thr14/Tyr15 phosphorylation was induced when Cdc2 kinase activity was inhibited with butyrolactone-I. Given these complications, we undertook a more critical analysis of the mechanisms that regulate Cdc2 after DNA damage. Caffeine reversed the DNA damage-induced inhibition of Cdc2 by causing dephosphorylation of Cdc2, and this dephosphorylation still occurred even when the Cdc2 feedback loops were blocked with butyrolactone-I. These data suggest that the DNA damage checkpoint in part acts through Thr14/Tyr15 phosphorylation by a mechanism independent of Cdc2 activity, and this phosphorylation can be accentuated by the Cdc2 feedback loops involving Thr14/Tyr15 protein kinases and phosphatases. The kinase activity of the Wee1Hu Tyr15 protein kinase was unaltered after DNA damage, but the phosphatase activity of Cdc25C was reduced. Thus, the decrease in Cdc25C activity may in part account for the DNA damage-induced increase in Thr14/Tyr15 phosphorylation. PMID- 9371522 TI - Roswell Park Cancer Institute Symposium: molecular approaches to cancer therapeutics. PMID- 9371521 TI - Cloning and expression of a developmentally regulated transcript MXR7 in hepatocellular carcinoma: biological significance and temporospatial distribution. AB - Using the differential display method to analyze mRNA expression in hepatocellular carcinoma (HCC) and nontumor livers, we cloned a full-length cDNA of 2263 bp, which was designated GTR2-2 and was identical with MXR7. The MXR7 mRNA was detected in 143 of 191 (74.8%) primary and recurrent HCCs taken from 154 patients but only in 5 (3.2%) nontumor livers. MXR7 mRNA was detected in one of two hepatoblastomas but not in hepatocellular adenoma, cholangiocarcinoma, or metastatic carcinomas to the liver. In human cancer of other anatomical sites, MXR7 mRNA was detected in low levels in one Wilms' tumor and in 4 of 40 gastric adenocarcinomas but not in several other types of cancer and 21 nonhepatocellular human tumor cell lines examined. MXR7 mRNA was expressed in high levels in the placenta, fetal liver, lung, and kidney, but it was undetectable in adult liver and was expressed in very low levels in adult lung and kidney. Our observations suggest that the MXR7 gene is regulated developmentally and expressed preferentially in HCC. To study its potential biological significance, we selected 113 patients who had unicentric primary HCC and had been followed for more than 4 years for further analysis. The MXR7 mRNA expression correlated closely with elevated serum alpha-fetoprotein (AFP) levels (88 versus 55%; P = 0.0001) and with expression of AFP mRNA (87 versus 55%; P = 0.005) and CD24 mRNA in HCC (80 versus 50%; P < 0.04), high tumor grade (76 versus 56%; P = 0.05), and tumor invasion (76 versus 55%; P < 0.05), but not with patient outcome. In HCC < or =3 cm, the frequency (77%) of MXR7 mRNA expression was significantly higher than that of elevated serum AFP (43%; P < 0.007) and AFP mRNA expression in HCC (41%; P < 0.004). Thus, MXR7 may serve as a sensitive early tumor marker for HCC and warrants more study to better understand its biological function. PMID- 9371523 TI - Renal cell carcinoma: recent progress and future directions. PMID- 9371524 TI - Morphology of acute promyelocytic leukemia with cytogenetic or molecular evidence for the diagnosis: characterization of additional microgranular variants. AB - Early diagnosis of t(15;17) acute promyelocytic leukemia (APL) is essential because of the associated disseminated intravascular coagulation and the unique response of the disease to all-trans retinoic acid (ATRA) therapy. Early diagnosis depends primarily on morphological recognition. The French-American British (FAB) classification, however, does not describe all morphological variations that occur in APL. In 25 cases with evidence of APL confirmed by cytogenetic and/or molecular analysis, we found a heterogeneous morphological group. The most common form of APL was heterogeneous and consisted of various combinations of cells in which hypergranular cells and some cells with multiple Auer rods were obvious. In some cases, one cell predominated. This led to the description of five subcategories. These included the classical FAB M3 with hypergranular cells and multiple Auer rods; the FAB variant with hypogranular bilobed cells; the basophilic cell type of McKenna et al. [Br. J. Haematol 50:201, 1982]; and two additional subtypes, one consisting of differentiated promyelocytes and a few blast cells (M2-like), and the other consisting largely of blast cells and a few early promyelocytes (M1-like). Immunophenotyping revealed a pattern of CD33 and/or CD13 positivity, and CD14 and HLA-DR negativity in 96% of cases. CD2 was positive in the FAB variant and in the subtype with basophilic cells, but negative with other subtypes. Three out of five cases with basophilic cell predominance [McKenna et al.: Br J Haematol 50:201, 1982], and one out of two M2-like cases, responded to ATRA therapy. Awareness of the heterogeneity and the atypical morphologic subtypes found in t(15;17) APL will contribute to improved recognition and early institution of ATRA therapy. PMID- 9371525 TI - Reduction of heat-shock protein-70 after prolonged treatment with retinoids: biological and clinical implications. AB - Heat shock proteins (HSPs) are a group of highly conserved polypeptides involved in cellular response to heat or other physical or chemical stresses. It has been recently reported that HSPs could play a role in cellular differentiation. In this study we have evaluated, by a cytofluorimetric method, the presence of HSP 70 in HL-60 cells during treatment with all-trans retinoic acid (ATRA), 9-cis retinoic acid (9-cis RA), and 13-cis retinoic acid (13-cis RA). After 1 and 3 days of incubation at 10(-7) M, HSP-70 did not show any variation compared to control; prolonging the exposure, together with the appearance of cellular differentiation along the granulocytic pathway and apoptosis, a progressive decrease of HSP-70 was observed that, after 8 days of treatment, was reduced by 40% with ATRA and by 28% with 9-cis RA compared to untreated samples, while only minimal changes were evident by incubating the cells with 13-cis RA. Reduction of HSP-70 was not associated with decreased protein synthesis, as demonstrated by [3H] leucine incorporation. Double labeling with propidium iodide showed a decrease in HSP-70 in all the phases of the cell cycle concomitant with a reduced percentage of cycling cells in ATRA-treated samples. Dot blot and Northern blot analysis demonstrated no change in HSP-70 mRNA after retinoid treatment, thus suggesting a post-transcriptional regulation of the phenomenon. This reduced production of HSP-70 caused by ATRA and by 9-cis RA, though to a lesser extent, could render the cells more sensitive to cytotoxic agents and could provide the rationale for the efficacy of ATRA + chemotherapy combinations. PMID- 9371526 TI - Hyperinsulinemia accompanying hyperglycemia in Chinese patients with aplastic anemia. AB - Serum insulin, and plasma glucagon and glucose levels were measured in 56 Chinese patients with aplastic anemia (AA) and 40 normal controls. Serum insulin and plasma glucose levels in 18 newly diagnosed cases and 11 previously treated cases with prednisone were significantly higher than those in the controls. Serum insulin and plasma glucose levels in 27 cases previously treated with stanozolol were significantly higher than those in the newly diagnosed cases and the previously treated cases with prednisone. There was no significant difference in plasma glucagon levels between the patients and the controls. Serum insulin and plasma glucose levels were significantly correlated with the amount of blood transfusions and serum ferritin and cortisone concentrations in the AA patients. Our findings suggest that AA patients may have hyperinsulinemia accompanying hyperglycemia, which can be further aggravated by stanozolol and prednisone therapy and iron overload. PMID- 9371527 TI - Intravascular lymphomatosis presenting as adult respiratory distress syndrome. AB - An unusual case of intravascular lymphomatosis caused by small noncleaved, non Burkitt's lymphoma, which presented with adult respiratory distress syndrome, is described. Extensive invasion of the small- and medium-size blood vessels of the lung, liver, spleen, kidneys, heart, esophagus, stomach, small and large intestines, bladder, and brain-but not the bone marrow or peripheral blood-is documented. The possible mechanism and the unusual features of this case are discussed in comparison with previously reported cases. The pertinent literature is reviewed. The problem of diagnosing this pathological entity is emphasized. PMID- 9371528 TI - Human umbilical cord blood myeloid progenitor cells are relatively chemoresistant: a potential model for autologous transplantations in HIV-infected newborns. AB - Vertical transmission from mother to child occurs in 15-39% of women infected with the human immunodeficiency virus (HIV). Stem cell transplantation has recently been suggested as a potential therapy for patients with HIV infection. We have examined the possible advantages of human cord blood (HUCB) stem cells over bone marrow (BM) stem cells in the treatment of HIV-infected newborns. HUCB myeloid progenitors were found to be statistically more resistant to interferon alpha (IFN-alpha), cytarabine (ARA-C), and eilatin than BM myeloid progenitor cells grown with IL-3 (P < 0.05). HUCB treated with IFN-alpha, ARA-C, and eilatin demonstrated a significantly higher capacity for self-renewal manifested by delta assay following 7 days in liquid culture. We, therefore, suggest that HUCB purged by anti-HIV drugs may be a source for autologous transplantation in HIV-infected newborns. PMID- 9371529 TI - Thrombotic complications in essential thrombocythemia with relatively low platelet counts. AB - Essential thrombocythemia (ET) is often associated with thrombotic and hemorrhagic complications, mostly at platelet counts exceeding 600 x 10(9)/L. There are, however, a few reports of such complications in ET at considerably lower platelet levels and the therapeutic approach to affected patients with relatively low platelet counts is still controversial. In the present study, the first to directly address the issue of hemostatic manifestations at relatively low platelet counts, we have determined the lowest platelet counts associated with such manifestations in 56 consecutive ET patients. Clinical manifestations related to ET were recorded in 46 (82%) patients. Of the symptomatic patients, 32 (70%) had symptoms at platelet counts lower than 600 x 10(9)/L, 23 (50%) at counts lower than 500 x 10(9)/L, 10 (22%) at counts lower than 400 x 10(9)/L, and 6 patients (13%) at platelet counts as low as 300-350 x 10(9)/L. Severe complications occurred at platelet counts lower than 600 x 10(9)/L in 10 patients (22%), lower than 500 x 10(9)/L in 7 (15%), and at lower than 400 x 10(9)/L in 2 (4%). Thrombotic neurologic symptoms were the most common (31 patients, 67%), followed by peripheral vascular symptoms (17 patients, 37%); hemorrhagic complications were relatively rare (3 patients, 7%). In most cases, cessation or improvement of clinical manifestations was observed only after further reduction in platelet counts. In conclusion, thrombotic manifestations, including severe ones, are not uncommon in ET at relatively low platelet counts. We recommend that symptomatic patients with relatively low platelet counts be treated and the platelet counts further reduced well into the lower normal range. PMID- 9371530 TI - Immunological abnormalities in splenic marginal zone cell lymphoma. AB - The clinical features of patients with splenic marginal zone cell lymphoma (SMZCL) have rarely been reported. In the present study, immunological abnormalities, particularly hematological abnormalities, observed in SMZCL were described. Autoimmune hemolytic anemia, immune thrombocytopenia, and appearance of lupus anticoagulant were observed in 2 of 3 patients with SMZCL. Other abnormal data including monoclonal gammopathy and cold agglutinin were also observed in 2 of the 3 patients. Immunological abnormalities may be characteristic complications in patients with SMZCL and must be followed carefully, since they may be a reliable marker of this type of lymphoma activity. PMID- 9371531 TI - De novo mutation of the beta-globin gene initiation codon (ATG-->AAG) in a Northern European boy. AB - We present a case of beta-thalassemia intermedia involving a 13-year-old boy of Northern European descent. His mother, father and older sister have normal hematologic indices. Molecular studies demonstrate that the proband carries a novel mutation of the beta-globin gene initiation codon (ATG-->AAG) which should give rise to beta(0)-thalassemia trait. The possibility of non-paternity was excluded, indicating that the novel mutation was the result of a de novo event. A review of the literature indicates that mutations involving the beta-globin gene initiation codon can give rise to a more severe phenotype than is generally associated with most other beta(+) or beta(0) mutations. PMID- 9371532 TI - Severe thrombocytopenia suggesting immunological mechanisms in two cases of vivax malaria. AB - Case 1: A 27-year-old woman, referred to our hospital because of relapsing fever after travel to Thailand, was given a diagnosis of vivax malaria. Clinical investigation revealed thrombocytopenia, elevated platelet-associated IgG (PAIgG), and negative antibody against Plasmodium vivax antigen. After antimalarial treatment, the levels of both the platelets and PAIgG returned to normal. Case 2: A 28-year-old Sri Lankan man was admitted to our hospital with a complaint of fever. The patient had thrombocytopenia, elevated PAIgG, and positive antibody against Plasmodium vivax antigen. He contracted malaria in Sri Lanka about 6 months prior to this admission. After treatment, the platelet count and PAIgG level returned to normal. In these two cases, high levels of PAIgG may have been involved in the development of the thrombocytopenia. In the first patient, in particular, the thrombocytopenia was thought to be induced by some immunological mechanism prior to the detection of antimaralial antibodies in serum. PMID- 9371533 TI - Codon 4 ACT-->ACA, codon 5 CCT-->TCT, and codon 6 GAG-->TAG mutations in cis position: a form of thalassemia trait. AB - A female of Uttar Pradesh, of Indian origin, who had a transfusion-dependent child, carried codon 4 ACT-->ACA, codon 5 CCT-->TCT, and codon 6 GAG-->TAG mutations at the cis position. The mutation was detected through sequencing of the amplified beta-globin gene. Heterozygosity is expressed as a thalassemia trait with moderate anemia, low MCV (57 fl), raised HbA2 (6.7%), and normal fetal hemoglobin (1.4%). PMID- 9371534 TI - Cerebral infarct associated with factor V Leiden mutation in a boy with hemophilia A. AB - An 11-year-old boy with mild hemophilia A was admitted to our hospital because of focal convulsions. Magnetic resonance imaging showed an old occipital infarct. Protein C, S, antithrombin III, anticardiolipin antibodies and fibrinogen were normal. Heterozygosity for factor V Leiden mutation was detected. We suggest that factor V Leiden mutation should be studied in hemophiliacs with thrombosis. PMID- 9371535 TI - Oral high-dose methylprednisolone and intravenous immunoglobulin treatments in adult chronic idiopathic thrombocytopenic purpura. AB - Ten adult patient of chronic idiopathic thrombocytopenic purpura (CITP) used oral prednisone and were treated with seven doses of oral high-dose methylprednisolone (30 mg/kg). Nine of ten patients responded after HDMP treatment (plt > 150 x 10(9)/L). Two patients having 8 and 10 years of history achieved long-term remission after first HDMP treatment. One unresponsive and one responsive patients did not accept IVIG treatment as second therapy and lost the follow-up. The remaining six patients received IVIG (0.5 mg/kg for 5 days) as second therapy after 3 months. Platelet count increased above 150 x 10(9)/L in 4 patients and between 60-80 x 10(9)/L in 2 patients. The peak platelet counts of both therapy users were higher under HDMP than IVIG therapy (252 +/- 110.4 vs 174.2 +/- 83.7 x 10(9)/L), but the difference was not significant. Responses were transient and returned to pretreatment values at 14-30 days, excluding long-term remission of 2 (2/10) patients after HDMP treatment. No side effect was observed. Thus, oral HDMP appears a good initial therapy for continuous remission in a small ratio of patients and a good security for emergency situations and prior to surgery in adult CITP patients. PMID- 9371536 TI - T-acute lymphoblastic leukemia with cytoplasmic granules. PMID- 9371538 TI - Simultaneous occurrence of lupus anticoagulant and factor VIII inhibitors. PMID- 9371537 TI - Mast cell disease mimicking granulocytic sarcoma. PMID- 9371539 TI - Effects of clomipramine and desipramine on a C-fiber reflex in rats. AB - A C-fiber nociceptive reflex evoked by electrical stimulation within the territory of the sural nerve, was recorded from the ipsilateral biceps femoris muscle in urethane anesthetized rats. Intravenously administered clomipramine and desipramine produced a dose-dependent depression of the C-fiber reflex. High doses of intrathecal desipramine also inhibited the C-fiber reflex, while similar intrathecal doses of clomipramine produced only a modest inhibition of the response. Intracerebroventricular administration of clomipramine decreased dose dependently the C-fiber reflex whereas intracerebroventricular desipramine increased this reflex. These findings suggest that tricyclic antidepressants with noradrenergic selectivity, as desipramine, inhibit the spinal processing of C inputs by acting directly at the spinal cord level, while those with serotonergic spectra, as clomipramine, depress the C-fiber-evoked spinal reflex by acting at a supraspinal modulatory site. PMID- 9371540 TI - Spinal calmodulin inhibitors reduce N-methyl-D-aspartate- and septide-induced nociceptive behavior. AB - The effect of two calmodulin inhibitors, W-7 (N-(6-aminohexyl)-5-chloro-1 naphtalenesulfonamide) and calmidazolium, on the nociceptive behavior induced by the intrathecal injection of NMDA (N-methyl-D-aspartate), AMPA (alpha-amino-3 hydroxy-5-methyl-4-iso xazolepropionic acid) or of septide is described. Lumbar intrathecal injection of NMDA, AMPA or septide induced a caudally directed nociceptive reaction (biting, scratching and licking). The nociceptive behavior induced by NMDA (4 microg) was dose dependently inhibited when W-7 (0.25-1 micromol/rat) or calmidazolium (0.12-0.5 micromol/rat) was coinjected. Biting, scratching and licking produced by AMPA (2 microg) were unaffected by intrathecal calmodulin inhibitors. Finally, septide-evoked nociceptive behavior (2 microg) was antagonized by W-7 (0.12-0.5 micromol/rat) and calmidazolium (0.06-0.25 micromol/rat). Thus, calmodulin inhibitors prevent the nociceptive reaction evoked by drugs that modify intracellular Ca2+, NMDA and septide, without affecting the nociceptive response induced by AMPA, for which Ca2+ is not the main second messenger. PMID- 9371541 TI - Effects of Ca2+ channel antagonists on sinus node: prolongation of late phase 4 depolarization by efonidipine. AB - Effects of various Ca2+ channel antagonists on the action potential configuration of rabbit sino-atrial node tissue were examined with standard microelectrode techniques. All Ca2+ channel antagonists decreased the maximum rate of phase 0 depolarization (Vmax) and increased the cycle length. The potency order to increase the cycle length was nisoldipine = verapamil > nifedipine = clentiazem > efonidipine > diltiazem. The potency order to decrease Vmax and to shift the threshold potential to a positive direction was the same as that to increase the cycle length, indicating that the major mechanism of negative chronotropism was inhibition of the L-type Ca2+ current. All Ca2+ channel antagonists except efonidipine shifted the maximum diastolic potential to the positive direction, decreased the action potential amplitude and prolonged the action potential duration. The effects of nifedipine were slightly weaker than those of other drugs when compared at equally bradycardiac concentrations. These differences may reflect differences in drug effects on currents other than the L-type Ca2+ current. A characteristic feature of efonidipine was selective suppression of the later phase of pacemaker depolarization with no effect on action potential amplitude and duration. Similar suppression of the later phase was observed with 50 microM Ni2+, which is reported to inhibit the T-type, but not L-type, Ca2+ current. Thus, efonidipine appears to suppress selectively the later phase of pacemaker depolarization through inhibition of both L- and T-type Ca2+ currents, which may be the underlying mechanism for its reported potent negative chronotropic but weak inotropic activity. PMID- 9371542 TI - Effect of cromakalim on the purinergic and cholinergic transmission in the rat detrusor muscle. AB - Contraction of the rat detrusor muscle is mediated by cholinergic and purinergic mechanisms. The present study was carried out to look at the influence of cromakalim, compared with atropine, suramin and nifedipine on the contractile response evoked by single shock and exogenous agonists (carbachol and ATP) in rat urinary bladder. Cromakalim was able to inhibit only partially the response to carbachol and profoundly affected the response to exogenous ATP. Atropine suppressed the response to carbachol and was inactive versus ATP. Suramin was inactive versus carbachol and was able to antagonize the response to ATP. Nifedipine proved to be a non-competitive antagonist versus carbachol (pD2 = 7.66 +/- 0.05) and deeply affected the response to ATP. Cromakalim inhibited only partially the first, purinergic, phase of the electrically evoked response but was able to inhibit in a concentration-dependent manner the second, cholinergic, phase (logIC50 = 6.87 +/- 0.05). Nifedipine blocked both the phases. Atropine blocked partially only the second phase. Suramin inhibited the first phase but, at least partially, also the second one. The combination of atropine and suramin enhanced the inhibition of the second phase. The antagonistic effect of suramin on the second phase could indicate an overlap of the purinergic and cholinergic components. The comparison between pre- and postjunctional effects indicates that cromakalim acts on purinergic transmission predominantly postjunctionally. On the contrary, the action on cholinergic transmission seems to occur mainly at prejunctional level. This conclusion can be relevant in view of the claimed importance of K+ channel openers in the treatment of urinary disorders. PMID- 9371543 TI - Differential effects of voltage-dependent Ca2+ channels on low and high frequency mediated neurotransmission in guinea-pig ileum and rat vas deferens. AB - The omega-conotoxins GVIA, MVIIA, MVIIC and SVIB reduced in a concentration dependent manner the low frequency electrically stimulated twitch response of the guinea-pig ileum and rat vas deferens. The relative activities of the conotoxins showed some difference between the two preparations in that for ileum it was MVIIA = GVIA > MVIIC = SVIB and for the vas deferens it was MVIIA > GVIA >> SVIB > MVIIC. High frequency electrical stimulation of both preparations resulted in a neurally-mediated omega-conotoxin GVIA resistant component that was sensitive to high concentrations of either omega-conotoxin MVIIC (300 nM- 1 microM) or omega agatoxin IVA (300 nM-1 microM) but not to omega-conotoxin MVIIA. Lower levels of either omega-conotoxin MVIIC or omega-agatoxin IVA (30-100 nM) failed to significantly affect the omega-conotoxin GVIA resistant component. This omega conotoxin GVIA resistant component was large in the ileal preparation comprising 30-40% of the maximal response at 20 Hz but relatively small (10%) in the vas deferens. These studies revealed that the N-type voltage-dependent calcium channel (VDCCs) exclusively controls neurotransmission during low frequency stimulation but at higher frequencies there is an additional non-adrenergic, non cholinergic (NANC) neurotransmission that appears to be regulated via Q-type VDCC. PMID- 9371544 TI - Effects of selective activation of dopamine D2 and D3 receptors on prolactin secretion and the activity of tuberoinfundibular dopamine neurons. AB - Dopamine agonists with activity at both dopamine D2 and D3 receptor subtypes stimulate tuberoinfundibular dopamine neurons and inhibit prolactin secretion from the anterior pituitary. The purpose of the present study was to identify the dopamine receptor subtypes mediating these effects using recently developed selective agonists for dopamine D2 (PNU-95,666) and D3 (PD128907) receptors. The activity of tuberoinfundibular dopamine neurons was estimated by measuring either the synthesis (accumulation of 3,4-dihydroxyphenyl-alanine [DOPA] following inhibition of decarboxylase activity) or metabolism (3,4-dihydroxyphenylacetic acid [DOPAC] concentrations) of dopamine in the median eminence, the region of the hypothalamus containing axon terminals of these neurons. In one experiment, the activity of mesolimbic dopamine neurons was also determined by measuring DOPA accumulation in terminals of these neurons in the nucleus accumbens. Activation of dopamine D2 receptors with PNU-95,666 caused dose- and time-related increases in DOPAC concentrations in median eminence which were temporally correlated with decreases in plasma prolactin concentrations. Activation of dopamine D3 receptors with PD128907 decreased DOPA concentrations in the nucleus accumbens, but had no effect on concentrations of DOPAC or DOPA in the median eminence or prolactin in plasma. These results reveal that tuberoinfundibular dopamine neurons are regulated by dopamine D2 rather than D3 receptors, and suggest that the ability of mixed dopamine D2/D3 receptor agonists to increase the activity of these neurons is mediated by an action at dopamine D2 receptors. Furthermore, these results confirm that tuberoinfundibular dopamine neurons are not regulated by inhibitory dopamine D2 or D3 autoreceptors. PMID- 9371545 TI - The phosphatidylinositol 3-kinase inhibitor wortmannin markedly reduces chemotactic peptide-induced locomotion and increases in cytoskeletal actin in human neutrophils. AB - To define a possible role of the enzyme phosphatidylinositol 3-kinase (PI 3 kinase) in motile functions of neutrophils, we have used a potent inhibitor of this enzyme, [1S-(1alpha,6b alpha,9a beta,11alpha,11bbeta)]-1-(acetyloxy) 1,6b,7,8,9a,10,11 ,11b-octahydro-1-(methoxymethyl)-9a,11b-dimethyl-3H-furo[4,3,2 de]indeno [4,5-h]-2-benzopyran-3,6,9-trione (wortmannin). Wortmannin markedly attenuated chemotactic peptide-induced development of polarity, locomotion and increases in cytoskeletal actin and alpha-actinin in human neutrophils at low, nM, concentrations (ED50 = 4-40 nM; 0.4-3 pmol/10(6) cells). The increase in cytoskeletal actin induced by phorbol-12-myristate-13-acetate in contrast was not affected by wortmannin (18 pmol/10[6] cells). Moreover, the increase in total F actin induced by an incubation for 1 min with chemotactic peptide was much less sensitive to wortmannin than increases in cytoskeletal actin; 80 pmol/10(6) cells were necessary for half-maximal inhibition. Wortmannin thus appears to primarily affect F-actin organization, rather than polymerization. Inhibition of development of polarity by wortmannin correlated with inhibition of production of phosphatidylinositol 3,4,5-trisphosphate. According to our findings, activation of a wortmannin-sensitive target, very likely PI 3-kinase, is required for optimal chemotactic peptide-induced neutrophil motility. PMID- 9371546 TI - Alpha2-adrenoceptor regulation of adenylyl cyclase in CHO cells: dependence on receptor density, receptor subtype and current activity of adenylyl cyclase. AB - Chinese hamster ovary (CHO) cells stably transfected to express different densities of the human alpha2A-, alpha2B- and alpha2C-adrenoceptor subtypes, were used to characterize the regulation of adenylyl cyclase activity by alpha2 adrenoceptor agonists. In isolated cell membranes, activation of alpha2A- and alpha2C-adrenoceptors did not affect basal enzyme activity, but activation of alpha2B-adrenoceptors stimulated adenylyl cyclase activity. The extent of stimulation was dependent on the receptor density and was insensitive to pertussis toxin treatment. In the presence of 10 microM forskolin all three receptor subtypes mediated inhibition of adenylyl cyclase activity in a pertussis toxin-sensitive manner. In experiments performed with intact cells the same pattern could be seen: the basal production of cAMP was not affected when alpha2C adrenoceptors were activated, but activated alpha2B-adrenoceptors mediated stimulation of cAMP production. In the presence of forskolin, both receptor subtypes mediated inhibition of cAMP production. Our results suggest that alpha2B adrenoceptors are coupled to both Gi and Gs proteins. The signal transduction pathway to which the receptor is coupled is not dependent on receptor density, but its effect on adenylyl cyclase regulation is dependent on the current activity of adenylyl cyclase. The results also suggest that the alpha2A- and alpha2C-subtypes are preferentially coupled to Gi and transduce only inhibition of adenylyl cyclase activity in transfected CHO cells. At low densities of alpha2C-adrenoceptors, clonidine was a partial agonist, but in clones expressing high levels of alpha2C-adrenoceptors, clonidine acted as a full agonist by inhibiting cAMP accumulation with the same efficacy as (-)-noradrenaline. This demonstrates that receptor reserve can mask partial agonist activity. PMID- 9371548 TI - The effect of the molecular mechanism of G protein-coupled receptor activation on the process of signal transduction. AB - A thermodynamic model of signal transduction that incorporates the possibility of multiple conformational states between the inactive and the active forms of the receptor was developed. The obtained equilibrium model is equivalent to the extended ternary complex of Samama et al. (J. Biol. Chem. 268 (1993) 4625-4636) if only two states of the receptor exist. These multiple equilibria between receptor states are modeled by two sets of equilibrium constants: K(piAR) and K(sigma piAR), in the presence of the ligand; and K(piR) and K(sigma piR), in the absence of the ligand. The higher the value of these constants, the more efficiently the active form of the receptor is generated. Intrinsic efficacy of the agonist is defined in the present formulation as the molecular processes induced by ligands in the receptor that lead to the active form of the receptor. Both the energetics (associated to K[piAR]) and mechanism of the process of receptor activation (associated to K[sigma piAR]) are important in eliciting the maximum response. Moreover, analytical expressions of basal activity, potency and maximum response were obtained. These definitions were used to classify the extra cellular ligand as agonists (K[sigma piAR] > K[sigma piR]), inverse agonists (K[sigma piR] > K[sigma piAR] > 0), neutral antagonists (K[sigma piAR] = K[sigma piR]), and pure antagonists. PMID- 9371549 TI - Influence of extracellular K+ concentration on the time-course of Na+/K+-ATPase inhibition by cardiac glycosides with fast and low binding kinetics. AB - The magnitude of the K+ antagonism of cardiac glycoside binding to Na+/K+-ATPase prepared from porcine heart, was estimated from the enzyme activities determined in the presence of different concentrations of K+ ([K+]), ouabain, and alpha methyl-digitoxigenin-glucoside, the latter showing a 30 fold greater dissociation rate than ouabain. An increase of [K+] (3-20 mmol/l) prolonged the half-lives of Na+/K+-ATPase inhibition and caused a rightward shift of the cardiac glycoside's dose-response curves by the same factor, almost maximal (4 fold) at 14 mmol/l K+. These data could be verified from the cardiac glycoside-elevated intravesicular Na+ concentrations of rat brain vesicles. These concentrations declined rapidly in brain vesicles treated with alpha-methyl-digitoxigenin-glucoside but not with ouabain after K+ was increased from 3.5 to 14 mM. The results suggest that the magnitude of the K+ antagonism under physiological conditions is only limited by the lifespan of the cardiac glycoside-binding E2P enzyme conformation reduced by K+. PMID- 9371547 TI - The rat mGlu1d receptor splice variant shares functional properties with the other short isoforms of mGlu1 receptor. AB - Three splice variants of the rat metabotropic glutamate receptor 1 (mGlu1a, 1b and 1c receptors) have been characterized so far. All have the same sequence up to the 46th residue following the 7th transmembrane domain, followed by different carboxyl-terminal tails. Whereas mGlu1b and mGlu1c receptors possess a short intracellular carboxyl-terminal tail, the mGlu1a receptor has a very long one. Compared to cells expressing mGlu1b or mGlu1c receptors, a higher agonist potency and basal phospholipase C activity were detected in cells expressing mGlu1a receptors. Another variant with a short carboxyl-terminal tail, the HmGlu1d receptor, has been recently isolated from human brain. Here we show that the mGlu1d receptor variant also exists in the rat. Like all rat mGlu1 receptor variants, the mGlu1d receptor activates phospholipase C upon stimulation with mGlu1 receptor agonists. Although the rank order of agonist potency is the same on mGlu1a and mGlu1d receptors, agonists are less potent in stimulating phospholipase C in mGlu1d receptor-expressing cells than in cells expressing mGlu1a receptors. Moreover, like the other short variants it has no significant constitutive activity. These results indicate that the mGlu1d receptor shares similar functional properties with the other short mGlu1 receptor splice variants, and further suggests that the long carboxyl-terminal tail of the mGlu1a receptor increases phospholipase C coupling efficacy. PMID- 9371550 TI - Different apparent modes of inhibition of alpha2A-adrenoceptor by alpha2 adrenoceptor antagonists. AB - The inhibition of alpha2A-adrenoceptor-mediated Ca2+ elevation by alpha2 adrenoceptor antagonists was measured in HEL human erythroleukemia cells. The antagonists could be divided in two classes: those that displayed surmountable inhibition (right-shift of the agonist dose-response curve), and those that displayed different degrees of insurmountable inhibition (depression of the maximum signal and a possible right-shift of the agonist dose-response curve). The degree of surmountability of the inhibition correlated well with the measured antagonist dissociation rates, suggesting that the hypothesis of the antagonist dissociation rate governing the mode of inhibition of fast responses, holds true. HEL cells thus provide a useful model system for the investigation of physiological consequences of different dissociation rates. Also, the dissociation rates of antagonists not available in radiolabelled form can be predicted from the functional data. The data stresses the importance of measurement of kinetic parameters of the drug-receptor interaction in addition to the equilibrium binding constants. PMID- 9371551 TI - Hexon-only binding of VP26 reflects differences between the hexon and penton conformations of VP5, the major capsid protein of herpes simplex virus. AB - VP26 is a 12-kDa capsid protein of herpes simplex virus 1. Although VP26 is dispensable for assembly, the native capsid (a T=16 icosahedron) contains 900 copies: six on each of the 150 hexons of VP5 (149 kDa) but none on the 12 VP5 pentons at its vertices. We have investigated this interaction by expressing VP26 in Escherichia coli and studying the properties of the purified protein in solution and its binding to capsids. Circular dichroism spectroscopy reveals that the conformation of purified VP26 consists mainly of beta-sheets (approximately 80%), with a small alpha-helical component (approximately 15%). Its state of association was determined by analytical ultracentrifugation to be a reversible monomer-dimer equilibrium, with a dissociation constant of approximately 2 x 10( 5) M. Bacterially expressed VP26 binds to capsids in the normal amount, as determined by quantitative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Cryoelectron microscopy shows that the protein occupies its usual sites on hexons but does not bind to pentons, even when available in 100 fold molar excess. Quasi-equivalence requires that penton VP5 must differ in conformation from hexon VP5: our data show that in mature capsids, this difference is sufficiently pronounced to abrogate its ability to bind VP26. PMID- 9371553 TI - Recombinant respiratory syncytial virus from which the entire SH gene has been deleted grows efficiently in cell culture and exhibits site-specific attenuation in the respiratory tract of the mouse. AB - The small hydrophobic protein SH of human respiratory syncytial virus (RSV) is a short transmembrane surface protein of unknown function. A full-length cDNA of RSV strain A2 (subgroup A) antigenomic RNA was modified such that the entire SH gene, including the transcription signals and the complete mRNA-encoding sequence, was deleted and replaced by a synthetic intergenic region. This reduced the length of the antigenome by 398 nucleotides and ablated expression of 1 of the 10 RSV mRNAs. Recombinant virus containing this engineered deletion was recovered, and the absence of the SH gene was confirmed by reverse transcription in conjunction with PCR. Northern blot analysis of intracellular RNAs and gel electrophoresis of labeled intracellular proteins confirmed the lack of expression of the SH mRNA and protein. The absence of the SH gene did not noticeably affect RNA replication, but two effects on transcription were noted. First, synthesis of the G, F, and M2 mRNAs was increased, presumably due to their being one position closer to the promoter in the gene order. Second, transcription of genes downstream of the engineered site exhibited a steeper gradient of polarity. On monolayers of HEp-2 cells, the SH-minus virus produced syncytia which were at least equivalent in size to those of the wild type and produced plaques which were 70% larger. Furthermore, the SH-minus virus grew somewhat better (up to 12.6-fold) than wild-type recombinant RSV in certain cell lines. While the function of the SH protein remains to be determined, it seems to be completely dispensable for growth in tissue culture and fusion function. When inoculated intranasally into mice, the SH-minus virus resembled the wild-type recombinant virus in its efficiency of replication in the lungs, whereas it replicated 10-fold less efficiently in the upper respiratory tract. In mice, the SH-minus and wild-type recombinant viruses were similarly immunogenic and effective in inducing resistance to virus challenge. PMID- 9371552 TI - Poliovirus 2C protein determinants of membrane binding and rearrangements in mammalian cells. AB - Poliovirus protein 2C is a 329-amino acid-protein that is essential for viral RNA synthesis and may perform multiple functions. In infected cells, it is associated with virus-specific membrane vesicles. Recombinant 2C protein expressed in transfected cells has been shown to associate with and induce rearrangement of the intracellular membrane network. This study was designed to map the determinants of membrane binding and rearrangement in the 2C protein. Computer assisted analysis of the protein sequence led to a prediction that the protein folds into a structure composed of three domains. Expression plasmids that encode each or combinations of these predicted domains were used to examine the abilities of the partial protein sequences to associate with intracellular membranes and to induce rearrangement of these membranes in HeLa cells. Biochemical fractionation procedures suggested that the N-terminal region of the protein was required for membrane association. Electron microscopic and immunoelectron microscopic observation showed that both the N- and C-terminal regions, but not the central portion, of 2C protein interact with intracellular membranes and induce major changes in their morphology. The central portion, when fused to the N-terminal region, altered the specific membrane architecture induced by the N-terminal region, giving rise to vesicles resembling those observed during poliovirus infection. PMID- 9371554 TI - Specific in vitro cleavage of a Leishmania virus capsid-RNA-dependent RNA polymerase polyprotein by a host cysteine-like protease. AB - Antibodies raised against baculovirus-expressed RNA-dependent RNA polymerase (RDRP) recognized a 95-kDa antigen and two smaller proteins in sucrose-purified Leishmania virus particles isolated from infected parasites. The 95-kDa antigen is similar in size to one predicted by translation of the RDRP open reading frame (ORF) alone. In an effort to reconcile in vitro observations of translational frameshifting on Leishmania RNA virus 1-4 transcripts, we have developed an in vitro cleavage assay system to explore the possibility that the fusion polyprotein is proteolytically processed. We show that coincubation a synthetic Cap-Pol fusion protein with lysates from Leishmania parasites yields major cleavage products similar in size to those encoded by the individual capsid and RDRP genes as well as the antigens detected in vivo. The major 82- and 95-kDa major cleavage products are specifically immunoprecipitated by capsid- or polymerase-specific antibodies, respectively, showing that cleavage occurs at or near the junction of the two functional domains. Protease inhibitor studies suggest that a cysteine-like protease is responsible for cleavage in the in vitro assay system developed here. From these results, we suggest that failure to detect a capsid-polymerase fusion protein produced by translational frameshifting in vivo may be due to specific proteolytic processing. PMID- 9371555 TI - Hygromycin B resistance mediates elimination of Leishmania virus from persistently infected parasites. AB - A series of pX63-HYG derivatives encoding Leishmania RNA virus 1-4 (LRV1-4) sequences were electroporated into cells of Leishmania strain M4147, a virus infected strain of L. guyanensis. After 6 weeks of drug selection (hygromycin B), transfected parasites lacked detectable quantities of viral genomic double stranded RNA, viral capsid protein, and RNA-dependent RNA polymerase (RDRP) activity. Evidence of viral infection was not recovered upon removal of the drug. While viral RNA transcripts were produced from electroporated expression vectors, as determined by reverse transcription-PCR, viral antigens were not detected, suggesting that the antiviral effects of hygromycin B are mediated through translation inhibition. A short-term selection study suggests that the LRV1-4 elimination may not only be a function of hygromycin B as a protein synthesis inhibitor but also possibly related to the mechanism of hygromycin B resistance in Leishmania strains. PMID- 9371557 TI - Directed integration of minute virus of mice DNA into episomes. AB - Recent studies with adeno-associated virus (AAV) have shown that site-specific integration is directed by DNA sequence motifs that are present in both the viral replication origin and the chromosomal preintegration DNA and that specify binding and nicking sites for the viral regulatory Rep protein. This finding raised the question as to whether other parvovirus regulatory proteins might direct site-specific recombination with DNA targets that contain origin sequences functionally equivalent to those described for AAV. To investigate this question, active and inactive forms of the minute virus of mice (MVM) 3' replication origin, derived from a replicative-form dimer-bridge intermediate, were propagated in an Epstein-Barr virus-based shuttle vector which replicates as an episome in a cell-cycle-dependent manner in mammalian cells. Upon MVM infection of these cells, the infecting genome integrated into episomes containing the active-origin sequence reported to be efficiently nicked by the MVM regulatory protein NS1. In contrast, MVM did not integrate into episomes containing either the inactive form of the origin sequence reported to be inefficiently nicked by NS1 or the active form from which the NS1 consensus nick site had been deleted. The structure of the cloned MVM episomal recombinants displayed several features previously described for AAV episomal and chromosomal recombinants. The findings indicate that the rules which govern AAV site-specific recombination also apply to MVM and suggest that site-specific chromosomal insertions may be achievable with different autonomous parvovirus replicator proteins which recognize binding and nicking sites on the target DNA. PMID- 9371556 TI - Utilization of chemokine receptors, orphan receptors, and herpesvirus-encoded receptors by diverse human and simian immunodeficiency viruses. AB - Human immunodeficiency virus type 1 (HIV-1) requires both CD4 and a coreceptor to infect cells. Macrophage-tropic (M-tropic) HIV-1 strains utilize the chemokine receptor CCR5 in conjunction with CD4 to infect cells, while T-cell-tropic (T tropic) strains generally utilize CXCR4 as a coreceptor. Some viruses can use both CCR5 and CXCR4 for virus entry (i.e., are dual-tropic), while other chemokine receptors can be used by a subset of virus strains. Due to the genetic diversity of HIV-1, HIV-2, and simian immunodeficiency virus (SIV) and the potential for chemokine receptors other than CCR5 or CXCR4 to influence viral pathogenesis, we tested a panel of 28 HIV-1, HIV-2, and SIV envelope (Env) proteins for the ability to utilize chemokine receptors, orphan receptors, and herpesvirus-encoded chemokine receptor homologs by membrane fusion and virus infection assays. While all Env proteins used either CCR5 or CXCR4 or both, several also used CCR3. Use of CCR3 was strongly dependent on its surface expression levels, with a larger number of viral Env proteins being able to utilize this coreceptor at the higher levels of surface expression. ChemR1, an orphan receptor recently shown to bind the CC chemokine I309 (and therefore renamed CCR8), was expressed in monocyte and lymphocyte cell populations and functioned as a coreceptor for diverse HIV-1, HIV-2, and SIV Env proteins. Use of ChemR1/CCR8 by SIV strains was dependent in part on V3 loop sequences. The orphan receptor V28 supported Env-mediated cell-cell fusion by four T- or dual-tropic HIV-1 and HIV-2 strains. Three additional orphan receptors failed to function for any of the 28 Env proteins tested. Likewise, five of six seven-transmembrane domain receptors encoded by herpesviruses did not support Env-mediated membrane fusion. However, the chemokine receptor US28, encoded by cytomegalovirus, did support inefficient infection by two HIV-1 strains. These findings indicate that additional chemokine receptors can function as HIV and SIV coreceptors and that surface expression levels can strongly influence coreceptor use. PMID- 9371558 TI - Characterization of infectious salmon anemia virus, an orthomyxo-like virus isolated from Atlantic salmon (Salmo salar L.). AB - Infectious salmon anemia (ISA) virus is the cause of infectious salmon anemia in farmed Atlantic salmon. The virus has been shown to contain RNA with structural characteristics similar to those of accepted members of the Orthomyxoviridae. Further biochemical, physiochemical, and morphological characterization of ISA virus was undertaken to clarify its taxonomic position. The virus was found to be sensitive to chloroform, heat, and low pH and agglutinated erythrocytes from fish. Erythrocytes from mammals or birds were not agglutinated. Receptor destroying enzyme activity was detected, and the nature of this enzyme was suggested to be an acetylesterase. The buoyant density of the virus was 1.18 g/ml in sucrose and CsCl gradients. The maximum rate of virus replication was observed at 15 degrees C, while no virus was produced at 25 degrees C. Actinomycin D inhibited viral replication, and viral antigen was detected in nuclei by immunofluorescence. The addition of trypsin to the culture medium during virus replication had a beneficial effect on virus replication. ISA virus contains four major polypeptides with estimated molecular sizes of 71, 53, 43, and 24 kDa. Electron microscopy revealed structures closely resembling the nucleocapsids of influenza virus. Mushroom-shaped surface projections were a distinctive morphological feature, which differed from the rod-shaped hemagglutinin projections of the influenza viruses. The data reported here support the relationship of ISA virus to the Orthomyxoviridae, although ISA virus differs from influenza viruses in some morphological characteristics and in showing restricted hemagglutination, in different specificity of the receptor-destroying enzyme, in different polypeptide profile, in being unable to replicate at temperatures above 25 degrees C, and in host range. PMID- 9371559 TI - Identification of spike protein residues of murine coronavirus responsible for receptor-binding activity by use of soluble receptor-resistant mutants. AB - We previously demonstrated by site-directed mutagenesis analysis that the amino acid residues at positions 62 and 214 to 216 in the N-terminal region of mouse hepatitis virus (MHV) spike (S) protein are important for receptor-binding activity (H. Suzuki and F. Taguchi, J. Virol. 70:2632-2636, 1996). To further identify the residues responsible for the activity, we isolated the mutant viruses that were not neutralized with the soluble form of MHV receptor proteins, since such mutants were expected to have mutations in amino acids responsible for receptor-binding activity. Five soluble-receptor-resistant (srr) mutants isolated had mutations in a single amino acid at three different positions: one was at position 65 (Leu to His) (srr11) in the S1 subunit and three were at position 1114 (Leu to Phe) (srr3, srr4, and srr7) and one was at position 1163 (Cys to Phe) (srr18) in the S2 subunit. The receptor-binding activity examined by a virus overlay protein blot assay and by a coimmunoprecipitation assay showed that srr11 S protein had extremely reduced binding activity, while the srr7 and srr18 proteins had binding activity similar to that of wild-type cl-2 protein. However, when cell surface receptors were used for the binding assay, all srr mutants showed activity similar to that of the wild type or only slightly reduced activity. These results, together with our previous observations, suggest that amino acids located at positions 62 to 65 of S1, a region conserved among the MHV strains examined, are important for receptor-binding activity. We also discuss the mechanism by which srr mutants with a mutation in S2 showed high resistance to neutralization by a soluble receptor, despite their sufficient level of binding to soluble receptors. PMID- 9371560 TI - Propagation of prion strains through specific conformers of the prion protein. AB - Two prion strains with identical incubation periods in mice exhibited distinct incubation periods and different neuropathological profiles upon serial transmission to transgenic mice expressing chimeric Syrian hamster/mouse (MH2M) prion protein (PrP) genes [Tg(MH2M) mice] and subsequent transmission to Syrian hamsters. After transmission to Syrian hamsters, the Me7 strain was indistinguishable from the previously established Syrian hamster strain Sc237, despite having been derived from an independent ancestral source. This apparent convergence suggests that prion diversity may be limited. The Me7 mouse strain could also be transmitted directly to Syrian hamsters, but when derived in this way, its properties were distinct from those of Me7 passaged through Tg(MH2M) mice. The Me7 strain did not appear permanently altered in either case, since the original incubation period could be restored by effectively reversing the series of passages. Prion diversity enciphered in the conformation of the scrapie isoform of PrP (PrP(Sc)) (G. C. Telling et al., Science 274:2079-2082, 1996) seems to be limited by the sequence of the PrP substrates serially converted into PrP(Sc), while prions are propagated through interactions between the cellular and scrapie isoforms of PrP. PMID- 9371561 TI - The ORF3 protein of hepatitis E virus is a phosphoprotein that associates with the cytoskeleton. AB - Hepatitis E virus (HEV) is a major human pathogen in the developing world. In the absence of an in vitro culture system, very little information exists on the basic biology of the virus. A small protein (approximately 13.5 kDa) of unknown function, pORF3, is encoded by the third open reading frame of HEV. We expressed pORF3 in transiently transfected COS-1 and Huh-7 cells and showed that it is a phosphoprotein which is modified at a serine residue(s). Deletion and site directed mutants were created to establish Ser-80 as the phosphorylation site. This residue is present within a conserved primary sequence that showed consensus sites for phosphorylation by p34cdc2 kinase (cdc2K) and mitogen-activated protein kinase (MAPK). In vitro experiments with hexahistidine-tagged pORF3 expressed either in Escherichia coli or in COS-1 cells showed efficient phosphorylation with exogenously added MAPK. The pORF3 mutants also exhibited an in vitro phosphorylation profile with MAPK which was identical to that observed in vivo. In its primary sequence, pORF3 possesses two highly hydrophobic N-terminal domains. On subcellular fractionation, pORF3 was found to partition with the cytoskeletal fraction, and this association with the cytoskeleton was lost on deletion of hydrophobic domain I (amino acid residues 1 to 32). These results suggest that HEV pORF3 is a cytoskeleton-associated phosphoprotein and are discussed in terms of a possible function for pORF3 within the HEV replicative cycle. PMID- 9371562 TI - Inhibition of endoplasmic reticulum-to-Golgi traffic by poliovirus protein 3A: genetic and ultrastructural analysis. AB - Poliovirus protein 3A, only 87 amino acids in length, is a potent inhibitor of protein secretion in mammalian cells, blocking anterograde protein traffic from the endoplasmic reticulum (ER) to the Golgi complex. The function of viral protein 3A in blocking protein secretion is extremely sensitive to mutations near the N terminus of the protein. Deletion of the first 10 amino acids or insertion of a single amino acid between amino acids 15 and 16, a mutation that causes a cold-sensitive defect in poliovirus RNA replication, abrogates the inhibition of protein secretion although wild-type amounts of the mutant proteins are expressed. Immunofluorescence light microscopy and immunoelectron microscopy demonstrate that 3A protein, expressed in the absence of other viral proteins, colocalizes with membranes derived from the ER. The precise topology of 3A with respect to ER membranes is not known, but it is likely to be associated with the cytosolic surface of the ER. Although the glycosylation of 3A in translation extracts has been reported, we show that tunicamycin, under conditions in which glycosylation of cellular proteins is inhibited, has no effect on poliovirus growth. Therefore, glycosylation of 3A plays no functional role in the viral replicative cycle. Electron microscopy reveals that the ER dilates dramatically in the presence of 3A protein. The absence of accumulated vesicles and the swelling of the ER-derived membranes argues that ER-to-Golgi traffic is inhibited at the step of vesicle formation or budding from the ER. PMID- 9371565 TI - Analysis of the internal replication sequence indicates that there are three elements required for efficient replication of minute virus of mice minigenomes. AB - Prior analysis of minigenomes of minute virus of mice carried out by our laboratory indicated that sequences within the region of nucleotides 4489 to 4695, inboard of the 5' palindrome, are required for efficient DNA replication of the virus and are the site of specific interactions with unidentified factors present in a host cell nuclear extract (P. Tam and C. R. Astell, Virology 193:812 824, 1993; P. Tam and C. R. Astell, J. Virology 68:2840-2848, 1994). In order to examine this region in finer detail, a comprehensive library of linker-scanning mutants spanning the region was tested for the ability to support replication of minigenome constructs and for the ability to interact with host cell factors. Three short discrete sequence elements critical for replication competence were observed. Binding of host cell nuclear factors was localized to four sites, with two major complexes each appearing to have two binding sites within the region. All factor binding sites were found to be directly adjacent to or overlapping with sequence elements contributing to replication competence, and evidence suggesting a correlation between factor binding and minigenome replication is presented. A possible model is proposed for function of a viral origin within the region of the internal replication sequence which addresses the still-unresolved problem of how parvoviruses overcome the thermodynamic energy barrier involved in the rearrangement of the 5'-terminal palindrome from an extended form to a hairpin conformation. PMID- 9371563 TI - Rotaviruses induce an early membrane permeabilization of MA104 cells and do not require a low intracellular Ca2+ concentration to initiate their replication cycle. AB - In this work, we found that rotavirus infection induces an early membrane permeabilization of MA104 cells and promotes the coentry of toxins, such as alpha sarcin, into the cell. This cell permeability was shown to depend on infectious virus and was also shown to be virus dose dependent, with 10 infectious particles per cell being sufficient to achieve maximum permeability; transient, lasting no more than 15 min after virus entry and probably occurring concomitantly with virus penetration; and specific, since cells that are poorly permissive for rotavirus were not permeabilized. The rotavirus-mediated coentry of toxins was not blocked by the endocytosis inhibitors dansylcadaverine and cytochalasin D or by the vacuolar proton-ATPase inhibitor bafilomycin A1, suggesting that neither endocytocis nor an intraendosomal acidic pH or a proton gradient is required for permeabilization of the cells. Compounds that raise the intracellular concentration of calcium ([Ca2+]i) by different mechanisms, such as the calcium ionophores A23187 and ionomycin and the endoplasmic reticulum calcium-ATPase inhibitor thapsigargin, did not block the coentry of alpha-sarcin or affect the onset of viral protein synthesis, suggesting that a low [Ca2+]i is not essential for the initial steps of the virus life cycle. Since the entry of alpha-sarcin correlates with virus penetration in all parameters tested, the assay for permeabilization to toxins might be a useful tool for studying and characterizing the route of entry and the mechanism used by rotaviruses to traverse the cell membrane and initiate a productive replication cycle. PMID- 9371564 TI - The roles of the human immunodeficiency virus type 1 Pol protein and the primer binding site in the placement of primer tRNA(3Lys) onto viral genomic RNA. AB - Factors that modulate the placement of primer tRNA(3Lys) onto the viral RNA genome in human immunodeficiency virus type 1 (HIV-1) were investigated through analysis of reverse-transcribed products that are extended from the tRNA(3Lys) primer. Mutations were introduced into the HIV-1 pol gene to result in the appearance of a stop codon in the open reading frame of the reverse transcriptase (RT) gene. These constructs, BH10-RT1 and BH10-RT2, yielded viruses with truncated Pol proteins. Alternatively, we altered the sequences involved in frameshifting by generating the construct BH10-FS. With each of these mutated viruses, we found that the primer tRNA(3Lys) that was placed onto viral genomic RNA was present in an unextended state. In contrast, as expected, tRNA(3Lys) in the case of wild-type BH10 virus had been extended by 2 bases. Furthermore, the amount of tRNA(3Lys) that was placed onto viral RNA in mutated viruses was significantly less than that placed in the wild-type virus. We also generated a mutant within the polymerase-active site of RT (D185H) (Asp-->His) that eliminated RT polymerase activity. We found that the placement of primer tRNA(3Lys) onto viral genomic RNA was independent of enzyme function; however, the tRNA(3Lys) that was placed was present in an unextended state due to the loss of RT activity. In contrast, the elimination of protease activity through a D25A (Asp-->Ala) point mutation in the protease-active site (construct BH10-PR) did cause a drop in the efficiency of tRNA(3Lys) placement. In this situation, a proportion of the placed tRNA(3Lys) was found to be extended by 2 bases, although not to the extent found with wild-type virus (BH10), due to a decrease in RT activity associated with unprocessed Gag-Pol protein that could not be cleaved because of the loss of protease activity. We also investigated the role of the primer binding site (PBS) in the placement of tRNA(3Lys) through a series of 2-, 4-, and 8-nucleotide (nt) deletions at the 3' end of the PBS, i.e., BH10-PBS2, BH10-PBS4, and BH10-PBS8, respectively. In mutated viruses BH10-PBS2 and BH10 PBS4, the 2-base-extended form of tRNA(3Lys) was still detected. However, less primer tRNA(3Lys) was placed onto viral genomic RNA as more nucleotides were deleted until the percentage of placement seen with wild-type BH10 virus dropped to only 4% in the virus with 8 nt deleted (BH10-PBS8). Consistently, these mutated viruses possessed decreased initial replication capacity compared with that of the wild-type virus, with the extent of incapacity corresponding to the size of the deletion. However, after several days, an increase in replication potential was accompanied by a reversion to a wild-type PBS. PMID- 9371566 TI - Structural, functional, and protein binding analyses of bovine papillomavirus type 1 exonic splicing enhancers. AB - Alternative splicing plays an important role in regulation of bovine papillomavirus type 1 (BPV-1) gene expression. We have recently identified in BPV 1 late pre-mRNAs two purine-rich exonic splicing enhancers (SE1 and SE2) which also stimulate splicing of a Drosophila doublesex (dsx) pre-mRNA containing a suboptimal 3' splice site. In vivo studies now demonstrate that both SE1 and SE2 are required for preferential use of the BPV-1 nucleotide (nt) 3225 3' splice site in nonpermissive cells. Deletion or mutation of either element in a BPV-1 late pre-mRNA switches splicing to the late-specific alternative 3' splice site at nt 3605. To investigate the sequence specificity of these exonic splicing enhancers, various mutant SE1 or SE2 elements were connected to dsx pre-mRNAs and tested for their stimulatory effects on dsx pre-mRNA splicing in vitro. Substitution of U residues for either A or G residues in and around potential ASF/SF2 binding sites in SE1 or SE2 resulted in a significant reduction of splicing enhancer activity. However, the G-to-U substitutions in both enhancers had the largest effect, reducing splicing to near control levels. Further in vitro analyses showed that splicing enhancement by SE2 could be competed with excess unlabeled SE2 RNA, indicating that SE2 activity in HeLa nuclear extracts is mediated by trans-acting factors. UV cross-linking plus immunoprecipitation assays showed that both wild-type SE1 and SE2 RNAs could bind directly to purified HeLa SR proteins SRp30a (ASF/SF2), SRp55, and SRp75. UV cross-linking experiments also identified a 23-kDa protein which binds to SE2 but not SE1. This protein is present in both HeLa nuclear extracts and S100 extracts but absent from SR protein preparations, suggesting that it is not a classical SR protein. Mutant SE elements (containing G- to U-mutations) which had minimal splicing enhancer activity also had very weak binding capacity for these proteins, strongly suggesting that the binding of these proteins is required for splicing enhancer function. PMID- 9371567 TI - A novel viral RNA species in Sindbis virus-infected cells. AB - Sindbis virus (SIN), the type alphavirus, has been studied extensively to identify the viral cis-acting sequences and proteins involved in RNA transcription and replication. However, very little is known about how these processes are coordinated. For example, synthesis of the genomic RNA and the subgenomic mRNA depends on the minus strand. Do these activities occur independently on different templates, or can replication and transcription take place simultaneously on the same template? We describe the appearance of a SIN specific, plus-sense RNA that is intermediate in size between the genomic and subgenomic RNA species. This RNA, designated RNA II, is observed in a number of different cell lines, both early and late in infection. The number of RNA II species, their sizes, and their abundances are influenced by the subgenomic promoter. We have mapped the 3' end of RNA II to a site within the subgenomic promoter, four nucleotides before the initiation site of the subgenomic mRNA. Our results indicate that the appearance of RNA II is correlated with subgenomic mRNA transcription, such that strong or active promoters tend to increase the abundance of RNA II, relative to weak or less active promoters. RNA II is most abundantly detected with the full promoter and is at much lower abundance with the minimal promoter. The possible origins of RNA II are discussed. PMID- 9371568 TI - The pseudorabies virus UL28 protein enters the nucleus after coexpression with the herpes simplex virus UL15 protein. AB - Herpesvirus DNA is packaged into capsids in the nuclei of infected cells in a process requiring at least six viral proteins. Of the proteins required for encapsidation of viral DNA, UL15 and UL28 are the most conserved among herpes simplex virus type 1 (HSV), varicella-zoster virus, and equine herpesvirus 1. The subcellular distribution of the pseudorabies virus (PRV) UL28 protein was examined by in situ immunofluorescence. UL28 was present in the nuclei of infected cells; however, UL28 was limited to the cytoplasm in the absence of other viral proteins. When cells expressing variant forms of UL28 were infected with a PRV UL28-null mutant, UL28 entered the nucleus, provided the carboxyl terminal 155 amino acids were present. Additionally, PRV UL28 entered the nucleus in cells infected with HSV. Two HSV packaging proteins were tested for the ability to affect the subcellular distribution of UL28. Coexpression of HSV UL15 enabled PRV UL28 to enter the nucleus in a manner that required the carboxyl terminal 155 amino acids of UL28. Coexpression of HSV UL25 did not affect the distribution of UL28. We propose that an interaction between UL15 and UL28 facilitates the transport of a UL15-UL28 complex to the infected-cell nucleus. PMID- 9371569 TI - The superantigen-homologous viral immediate-early gene ie14/vsag in herpesvirus saimiri-transformed human T cells. AB - Herpesvirus saimiri C488 transforms human T lymphocytes to stable growth in culture. The growth-transformed human T cells harbor the viral genome in a nonintegrated episomal form without production of virus particles. In these cells, virus gene expression was previously found to be confined to the transforming genes stpC and tip. In order to analyze virus gene expression in more detail, we applied a subtractive hybridization technique and compared stimulated virus-transformed cells with uninfected parental T cells of the same donor. A number of known T-cell activation genes were isolated. Viral stpC/tip cDNAs were enriched after subtraction. In addition, the viral immediate-early, superantigen-homologous gene ie14/vsag was represented by numerous cDNA clones that comprised the entire spliced transcript. Whereas a weak basal expression of ie14/vsag was detected by reverse transcription-PCR only, the phorbol ester induced transcripts were readily shown by Northern blotting. ie14/vsag, which before had been classified as a major immediate-early gene of herpesvirus saimiri, is localized within a highly conserved region with extensive homologies to the cellular genome. Mutant viruses without the ie14/vsag gene are replication competent and fully capable of transforming human and marmoset T cells. Since ie14/vsag is transiently expressed after stimulation, it may increase T-cell proliferation in an activation-dependent and superantigen-like but apparently Vbeta-independent way. PMID- 9371570 TI - B-cell lines immortalized with an Epstein-Barr virus mutant lacking the Cp EBNA2 enhancer are biased toward utilization of the oriP-proximal EBNA gene promoter Wp1. AB - During Epstein-Barr virus (EBV) latent infection of B lymphocytes in vitro, six viral nuclear antigens (EBNAs) are expressed from one of two promoters, Cp or Wp, whose activities have previously been shown to be mutually exclusive in established lymphoblastoid cell lines. Initially after infection, the EBNA genes are transcribed from Wp, which is present in multiples copies within the major internal repeat of EBV. Approximately 48 to 72 h postinfection, Wp is downregulated, with a corresponding increase in transcription from Cp. An EBNA2 responsive enhancer exists upstream of Cp, and a role for EBNA2 in the induction of Cp activity during the establishment of viral latency has previously been proposed (Woisetschlaeger et al., Proc. Natl. Acad. Sci. USA 87:1725-1729, 1991). To critically assess the potential role for this enhancer region in determining relative usage of Cp and Wp, an EBNA2 enhancer deletion mutant virus was generated. Lymphoblastoid cell lines were screened by PCR and Southern blotting for the presence of mutant virus harboring the EBNA2 enhancer deletion. A quantitative S1 nuclease protection assay was developed to allow comparison of relative Cp and Wp activities for the cell lines containing mutant virus and those of the wild-type recombinants which lacked the enhancer deletion. In general, the wild-type recombinants had higher levels of Cp-initiated transcripts than Wp-initiated transcripts. In contrast, the Cp EBNA2 enhancer deletion mutants exhibited a strong bias toward Wp activity. Notably, only the first Wp (oriP-proximal Wp; Wp1) appears active in these mutants. S1 nuclease protection assays using a probe which hybridizes to the W2 exon, contained in both Cp- and Wp-initiated transcripts, indicated that the total level of transcription from Cp and Wp remained the same in wild-type and EBNA2 enhancer mutant cell lines. The presence of both Cp and Wp activity in the wild-type recombinants, as well as in newly derived lymphoblastoid cell lines established with the prototype B95.8 virus, demonstrated that Cp and Wp activities are not always mutually exclusive. PMID- 9371571 TI - Astrocyte-specific expression of human T-cell lymphotropic virus type 1 (HTLV-1) Tax: induction of tumor necrosis factor alpha and susceptibility to lysis by CD8+ HTLV-1-specific cytotoxic T cells. AB - Human T-cell lymphotropic virus type 1 (HTLV-1) is associated with a chronic neurological disease termed HTLV-1-associated myelopathy/tropical spastic paraperesis (HAM/TSP). Although the pathogenesis of this disease remains to be elucidated, the evidence suggests that immunopathological mechanisms are involved. Since HTLV-1 tax mRNA was colocalized with glial acidic fibrillary protein, a marker for astrocytes, we developed an in vitro model to assess whether HTLV-1 infection activates astrocytes to secrete cytokines or present viral immunodominant epitopes to virus-specific T cells. Two human astrocytic glioma cell lines, U251 and U373, were transfected with the 3' portion of the HTLV-1 genome and with the HTLV-1 tax gene under astrocyte-specific promoter control. In this study, we report that Tax-expressing astrocytic glioma transfectants activate the expression of tumor necrosis factor alpha mRNA in vitro. Furthermore, these Tax-expressing glioma transfectants can serve as immunological targets for HTLV-1-specific cytotoxic T lymphocytes (CTL). We propose that these events could contribute to the neuropathology of HAM/TSP, since infected astrocytes can become a source for inflammatory cytokines upon HTLV-1 infection and serve as targets for HTLV-1-specific CTL, resulting in parenchymal damage by direct lysis and/or cytokine release. PMID- 9371573 TI - A mutation in tomato aspermy cucumovirus that abolishes cell-to-cell movement is maintained to high levels in the viral RNA population by complementation. AB - The nucleotide substitution C-->A at nucleotide 100 of tomato aspermy cucumovirus (TAV) strain V (V-TAV) RNA segment 3 (RNA3) introduces an ocher stop at the fourth codon of the movement protein open reading frame. Experiments with RNA transcripts from full-length clones showed that this mutation abolished cell-to cell movement and, thus, infectivity in planta. Heterogeneity analyses on stock V TAV virion RNA showed that an A at position 100 was present in the molecular population of RNA3 at a frequency of 0.76 and that a C at this position was present at a frequency of 0.24. This result indicates that a fraction of RNA3 molecules complements cell-to-cell movement of movement-defective molecules. It was shown that the mutation C-->A conferred enhanced RNA replication of the defective mutant in tobacco protoplasts. The effect of the mutation on replication was dependent on sequence context, since the same mutation did not affect the replication efficiency in the related TAV strain 1 RNA3. Competition experiments in tobacco protoplasts were done to estimate the fitness during a cell invasion cycle of the movement-defective mutant relative to the wild type (wt). From these data, a lower limit to the degree of complementation of movement defective molecules by movement-competent ones could be estimated as 0.13. This estimate shows that complementation may play an important role in the determination of genetic structure in RNA genome populations. A further effect of the enhanced replication of the movement-defective mutant was the efficient competition with the wt for the initiation of infection foci in planta. PMID- 9371572 TI - Rous sarcoma virus direct repeat cis elements exert effects at several points in the virus life cycle. AB - Two approximately 135-nucleotide (nt) direct repeats flank the Rous sarcoma virus (RSV) oncogene src and are composed of two smaller repeats, dr1 (approximately 100 nt) and dr2 (approximately 36 nt). These sequences have been reported to contain cis-acting signals necessary for RNA packaging and elements that allow cytoplasmic accumulation of unspliced RNA (cytoplasmic transport elements). In this report, we show that avian fibroblasts infected with the Prague A strain of RSV with precise deletions of both dr1 elements express src and are transformed by this mutant virus but production of virus particles is very low and virus spread throughout the culture requires several weeks. We show that the replication defect is due to complex effects on viral RNA transport, viral RNA half-life, and virus particle assembly. The dr1 elements may contain binding sites for a permissive cell-specific factor(s) that facilitates efficient nuclear cytoplasmic transport, RNA stability, and cytoplasmic utilization of unspliced viral RNA. The implications of these results for understanding the defects of nonpermissive virus infections in mammalian cells are discussed. PMID- 9371575 TI - Porcine reproductive and respiratory syndrome virus replicates in testicular germ cells, alters spermatogenesis, and induces germ cell death by apoptosis. AB - Like other arteriviruses, porcine reproductive and respiratory syndrome virus (PRRSV) is shed in semen, a feature that is critical for the venereal transmission of this group of viruses. In spite of its epidemiological importance, little is known of the association of PRRSV or other arteriviruses with gonadal tissues. We experimentally infected a group of boars with PRRSV 12068-96, a virulent field strain. By combined use of in situ hybridization and immunohistochemistry, we detected infection by PRRSV in the testes of these boars. The PRRSV testicular replication in testis centers on two types of cells: (i) epithelial germ cells of the seminiferous tubules, primarily spermatids and spermatocytes, and (ii) macrophages, which are located in the interstitium of the testis. Histopathologically, hypospermatogenesis, formation of multinucleated giant cells (MGCs), and abundant germ cell depletion and death were observed. We obtained evidence that such germ cell death occurs by apoptosis, as determined by a characteristic histologic pattern and evidence of massive DNA fragmentation detected in situ (TUNEL [terminal deoxynucleotidyltransferase-mediated digoxigenin-UTP nick end labeling] assay). Simultaneously with these testicular alterations, we observed that there is a significant increase in the number of immature sperm cells (mainly MGCs, spermatids, and spermatocytes) in the ejaculates of the PRRSV-inoculated boars and that these cells are infected with PRRSV. Our results indicate that PRRSV may infect target cells other than macrophages, that these infected cells can be primarily responsible for the excretion of infectious PRRSV in semen, and that PRRSV induces apoptosis in these germ cells in vivo. PMID- 9371574 TI - Repression of retrovirus-mediated transgene expression by interferons: implications for gene therapy. AB - Retrovirus-mediated gene transfer is commonly used in gene therapy protocols and has the potential to provide long-term expression of the transgene. Although expression of a retrovirus-delivered transgene is satisfactory in cultured cells, it has been difficult to achieve consistent and high-level expression in vivo. In this investigation, we explored the possibility of modulating transgene expression by host-derived cytokines. Normal human keratinocytes and dermal fibroblasts were transduced with recombinant retroviruses expressing a reporter gene (lacZ). Treatment of transduced cells with a proinflammatory cytokine, gamma interferon (IFN-gamma), significantly reduced lacZ expression to less than 25% of that of nontreated cells. The inhibition was concentration dependent (peak at 5 ng/ml) and time dependent (maximal at 16 h for transcript and 24 h for protein); expression remained repressed in the continued presence of IFN-gamma but returned to normal levels 24 h after IFN-gamma withdrawal. The decrease in beta galactosidase activity appeared to result from decrease in steady-state lacZ mRNA levels. Inhibitors of transcription and translation blocked IFN-gamma-induced repression, suggesting involvement of newly synthesized protein intermediates. Similar results were obtained by treatment of transduced cells with IFN-alpha but not with other proinflammatory cytokines, including tumor necrosis factor alpha, interleukin-2 (IL-1), IL-4, and granulocyte colony-stimulating factor. Although the level of lacZ mRNA was reduced by >70% following IFN treatment, the rate of lacZ transcription was not significantly different from that for nontreated cells. These results suggest that IFN-mediated regulation of transgene expression is at a posttranscriptional level. Interestingly, IFN-gamma also suppressed transgene expression driven by a cellular promoter (involucrin) inserted in an internal position in the retroviral vector. The presence of the overlapping 3' untranslated regions in transcripts initiated from the internal promoter and the long terminal repeat is suggestive of a posttranscriptional regulation, likely at the level of RNA stabilization. These results provide direct evidence for modulatory effects of IFNs on retrovirus-mediated transgene expression and suggest that gene therapy results may be altered by host inflammatory responses. PMID- 9371576 TI - Distinct pathogenic effects of group B coxsackieviruses on human glomerular and tubular kidney cells. AB - The six group B coxsackieviruses (CVBs) are highly prevalent human pathogens that cause viremia followed by involvement of different organs. Clinical and experimental evidence suggests that CVBs can induce kidney injury, but the susceptibility of human renal cells to these viruses is unknown. By using pure cultures of human glomerular and tubular cells, we demonstrated that all CVBs are capable of productively infecting renal cells of three different histotypes. Distinct pathogenic effects were observed. Proximal tubular epithelial cells and, to a lesser extent, glomerular podocytes were highly susceptible to CVBs; in both cases, infection led to cytolysis. In contrast, glomerular mesangial cells supported the replication of the six CVBs but failed to develop overt cytopathologic changes. Mesangial cells continued to produce infectious progeny for numerous serial subcultures (i.e., more than 50 days), especially with type 1, 3, 4, and 5 viruses. In the above cells, persistent infection induced the de novo synthesis of platelet-derived growth factor A/B and enhanced the release of transforming growth factor beta1/2. These two factors are important mediators of progression from glomerular inflammation to glomerulosclerosis. CVB replication appeared also to impair the phagocytic and contractile activity of mesangial cells. Loss of these properties--which are important in glomerular physiopathology--may contribute to the development of progressive nephropathy. The results show that CVBs induce distinct effects in different types of cultured renal cells and suggest that CVB infections may be associated with both acute and progressive renal injury. PMID- 9371577 TI - Shuttling of the herpes simplex virus type 1 regulatory protein ICP27 between the nucleus and cytoplasm mediates the expression of late proteins. AB - The herpes simplex virus type 1 (HSV-1) immediate-early protein ICP27 is required posttranscriptionally for the expression of HSV-1 late genes during a productive infection. ICP27 also inhibits host cell pre-mRNA splicing, effectively shutting off host cell protein synthesis. Here we describe intragenic suppressors of LG4, a virus with a conditional lethal mutation in the gene encoding ICP27. At the restrictive temperature, tsICP27 from LG4 fails to inhibit host cell pre-mRNA splicing and to activate the expression of HSV-1 late-gene products. Although the suppressors of LG4 restore virus growth, they still fail to inhibit host cell pre mRNA splicing. Thus, the role of ICP27 in the synthesis of late proteins is independent of host shutoff. In HSV-1-infected cells, ICP27 shuttles between the nucleus and the cytoplasm. Shuttling of ICP27 occurs only at late times during infection. In transfected cells, ICP27 shuttling was dependent on coexpression of RNA from a late HSV-1 gene. While shuttling does not occur in cells infected with LG4 at 39.5 degrees C, the suppressors of LG4 restore shuttling. Temperature shift experiments correlate the defect in shuttling with the temperature sensitive phenotype of LG4. These data provide a correlation between shuttling of ICP27 and the expression of HSV-1 late-gene products. We propose that ICP27 regulates late-gene protein synthesis by facilitating the export of late RNAs. PMID- 9371578 TI - The V3-directed immune response in natural human immunodeficiency virus type 1 infection is predominantly directed against a variable, discontinuous epitope presented by the gp120 V3 domain. AB - The specific binding of antibodies to the V3 loop in sera from human immunodeficiency type 1 (HIV-1)-infected individuals was investigated. Different V3 structures were analyzed as full-length loops or by pepscan. Our data show that on full-length V3 loops, both variable regions on either side of the tip of the loop (GPGRAF) contribute to a common epitope for type-specific antibodies. Type-specific antibodies bound strongly and at high titers to native V3 loops but negligibly once the loop was denatured. In contrast to the type-specific, discontinuous epitope, the linear, conserved epitopes presented by the full length V3 loop, the tip, the amino-terminal base, and the carboxy-terminal base were not accessible to serum antibody. When the V3 sequences were analyzed with linear peptides, antibodies bound preferentially to peptides containing the conserved GPGRAF sequence. Thus, two different specificities of V3-directed antibodies were detected in patient sera. Unlike group-specific antibodies directed against GPGRAF peptides, lack of type-specific antibodies directed against the discontinuous epitope was correlated with viral escape from autologous neutralization. Our data suggest that the full-length conformation of the V3 loop is accessible predominantly to highly type-specific antibodies present in sera from HIV-1-infected individuals. These antibodies are directed against discontinuous V3 epitopes, not against conserved linear V3 targets. The implications of these findings for viral escape and blockade of infection with V3 based vaccines are discussed. PMID- 9371579 TI - Activation of transgene expression by early region 4 is responsible for a high level of persistent transgene expression from adenovirus vectors in vivo. AB - The persistence of transgene expression has become a hallmark for adenovirus vector evaluation in vivo. Although not all therapeutic benefit in gene therapy is reliant on long-term transgene expression, it is assumed that the treatment of chronic diseases will require significant persistence of expression. To understand the mechanisms involved in transgene persistence, a number of adenovirus vectors were evaluated in vivo in different strains of mice. Interestingly, the rate of vector genome clearance was not altered by the complete deletion of early region 4 (E4) in our vectors. The GV11 (E1- E4-) vector genome cleared with a similar kinetic profile as the GV10 (E1-) vector genome in immunocompetent and immunocompromised mice. These results suggest that the majority of adenovirus vector genomes are eliminated from transduced tissue via a mechanism(s) independent of T-cell, B-cell, and NK cell immune mechanisms. While the levels of persistence of transgene expression in liver or lung transduced with GV10 and GV11 vectors expressing beta-galactosidase, cystic fibrosis transmembrane conductance regulator, or secretory alkaline phosphatase were similar in immunocompetent mice, a marked difference was observed in immunocompromised animals. Levels of transgene expression initially from both GV10 and GV11 vectors were the same. However, GV11 transgene expression correlated with loss of vector genome, while GV10 transgene expression persisted at a high level. Coadministration and readministration of GV10 vectors showed that E4 provided in trans could activate transgene expression from the GV11 vector genome. While transgene expression activity per genome from the GV10 vector is clearly activated, expression from a cytomegalovirus promoter expression cassette in a GV11 vector appeared to be further inactivated as a function of time. Understanding the molecular mechanisms underlying these expression effects will be important for developing persistent adenovirus vectors for chronic applications. PMID- 9371580 TI - Canine parvovirus host range is determined by the specific conformation of an additional region of the capsid. AB - We analyzed a region of the capsid of canine parvovirus (CPV) which determines the ability of the virus to infect canine cells. This region is distinct from those previously shown to determine the canine host range differences between CPV and feline panleukopenia virus. It lies on a ridge of the threefold spike of the capsid and is comprised of five interacting loops from three capsid protein monomers. We analyzed 12 mutants of CPV which contained amino acid changes in two adjacent loops exposed on the surface of this region. Nine mutants infected and grew in feline cells but were restricted in replication in one or the other of two canine cell lines tested. Three other mutants whose genomes contain mutations which affect one probable interchain bond were nonviable and could not be propagated in either canine or feline cells, although the VP1 and VP2 proteins from those mutants produced empty capsids when expressed from a plasmid vector. Although wild-type and mutant capsids bound to canine and feline cells in similar amounts, infection or viral DNA replication was greatly reduced after inoculation of canine cells with most of the mutants. The viral genomes of two host range restricted mutants and two nonviable mutants replicated to wild-type levels in both feline and canine cells upon transfection with plasmid clones. The capsids of wild-type CPV and two mutants were similar in susceptibility to heat inactivation, but one of those mutants and one other were more stable against urea denaturation. Most mutations in this structural region altered the ability of monoclonal antibodies to recognize epitopes within a major neutralizing antigenic site, and that site could be subdivided into a number of distinct epitopes. These results argue that a specific structure of this region is required for CPV to retain its canine host range. PMID- 9371581 TI - Fulminant hepatic failure in murine hepatitis virus strain 3 infection: tissue specific expression of a novel fgl2 prothrombinase. AB - Activation of the immune coagulation system has been implicated in the pathogenesis of fulminant liver failure caused by murine hepatitis virus strain 3 (MHV-3). The recent discovery of the fgl2 gene, which encodes for MHV-3-induced prothrombinase (fgl2 prothrombinase), allows for fundamental studies to determine the molecular basis for fulminant liver failure. Transcription of the fgl2 gene and translation of the protein it encodes were examined in the liver and other organs of susceptible mice following MHV-3 infection. No constitutive expression of the fgl2 gene or the fgl2 prothrombinase was detected. Within 12 to 24 h of MHV-3 infection, however, fgl2 gene transcripts were detected in large amounts in the liver, spleen, and lungs, all of which are rich in reticuloendothelial cells, but were only focally present in small amounts in the kidney and brain. There was sequential detection of fgl2 prothrombinase in the liver, where it was localized specifically to the endothelium of intrahepatic veins and hepatic sinusoids; this was allowed by fibrin deposition, which resulted in confluent hepatocellular necrosis. These results provide further evidence for the role of the selective expression of this novel fgl2 prothrombinase in the pathogenesis of MHV-3-induced fulminant liver failure. PMID- 9371582 TI - Cellular recombination pathways and viral terminal repeat hairpin structures are sufficient for adeno-associated virus integration in vivo and in vitro. AB - The human parvovirus adeno-associated virus (AAV) is unique in its ability to target viral integration to a specific site on chromosome 19 (ch-19). Recombinant AAV (rAAV) vectors retain the ability to integrate but have apparently lost this ability to target. In this report, we characterize the terminal-repeat-mediated integration for wild-type (wt), rAAV, and in vitro systems to gain a better understanding of these differences. Cell lines latent for either wt or rAAV were characterized by a variety of techniques, including PCR, Southern hybridization, and fluorescence in situ hybridization analysis. More than 40 AAV-rAAV integration junctions were cloned, sequenced, and then subjected to comparison and analysis. In both immortalized and normal diploid human cells, wt AAV targeted integration to ch-19. Integrated provirus structures consisted of head to-tail tandem arrays with the majority of the junction sequences involving the AAV inverted terminal repeats (ITRs). No complete viral ITRs were directly observed. In some examples, the AAV p5 promoter sequence was found to be fused at the virus-cell junction. Data from dot blot analysis of PCR products were consistent with the occurrence of inversions of genomic and/or viral DNA sequences at the wt integration site. Unlike wt provirus junctions, rAAV provirus junctions mapped to a subset of non-ch-19 sequences. Southern analysis supported the integration of proviruses from two independent cell lines at the same locus on ch-2. In addition, provirus terminal repeat sequences existed in both the flip and flop orientations, with microhomology evident at the junctions. In all cases with the exception of the ITRs, the vector integrated intact. rAAV junction sequence data were consistent with the occurrence of genomic rearrangement by deletion and/or rearrangement-translocation at the integration locus. Finally, junctions formed in an in vitro system between several AAV substrates and the ch 19 target site were isolated and characterized. Linear AAV substrates typically utilized the end of the virus DNA substrate as the point of integration, whereas products derived from AAV terminal repeat hairpin structures in the presence or absence of Rep protein resembled AAV-ch-19 junctions generated in vivo. These results describing wt AAV, rAAV, and in vitro integration junctions suggest that the viral integration event itself is mediated by terminal repeat hairpin structures via nonviral cellular recombination pathways, with specificity for ch 19 in vivo requiring additional viral components. These studies should have an important impact on the use of rAAV vectors in human gene therapy. PMID- 9371583 TI - Mechanisms for virus-induced liver disease: tumor necrosis factor-mediated pathology independent of natural killer and T cells during murine cytomegalovirus infection. AB - The contribution of endogenous NK cells and cytokines to virus-induced liver pathology was evaluated during murine cytomegalovirus infections of mice. In immunocompetent C57BL/6 mice, the virus induced a self-limited liver disease characterized by hepatitis, with focal inflammation, and large grossly visible subcapsular necrotic foci. The inflammatory foci were most numerous and contained the greatest number of cells 3 days after infection; they colocalized with areas of viral antigen expression. The largest number of necrotic foci was found 2 days after infection. Overall hepatic damage, assessed as increased expression of liver enzymes in serum, accompanied the development of inflammatory and necrotic foci. Experiments with neutralizing antibodies demonstrated that although virus induced tumor necrosis factor (TNF) can have antiviral effects, it also mediated significant liver pathology. TNF was required for development of hepatic necrotic foci and increased levels of liver enzymes in serum but not for increased numbers of inflammatory foci. The necrotic foci and liver enzyme indications of pathology occurred independently of NK and T cells, because mice rendered NK-cell deficient by treatment with antibodies, T- and B-cell-deficient Rag-/- mice, and NK- and T cell-deficient E26 mice all manifested both parameters of disease. Development of necrotic foci and maximally increased levels of liver enzymes in serum also were TNF dependent in NK-cell-deficient mice. Moreover, in the immunodeficient E26 mice, virus-induced liver disease was progressive, with eventual death of the host, and neutralization of TNF significantly increased longevity. These results establish conditions separating hepatitis from significant liver damage and demonstrate a cytokine-mediated component to viral pathogenesis. PMID- 9371584 TI - Discontinuous plus-strand DNA synthesis in human immunodeficiency virus type 1 infected cells and in a partially reconstituted cell-free system. AB - Human immunodeficiency virus type 1 (HIV-1) replication requires conversion of viral RNA to double-stranded DNA. To better understand the molecular mechanisms of this process, we examined viral DNA synthesis in a simple cell-free system that uses the activities of HIV-1 reverse transcriptase to convert regions of single-stranded HIV-1 RNA to double-stranded DNA in a single incubation. This system recapitulated several of the required intermediate steps of viral DNA synthesis: RNA-templated minus-strand polymerization, preferential plus-strand initiation at the central and 3' HIV-1 polypurine tracts, and DNA-templated plus strand polymerization. Secondary sites of plus-strand initiation were also observed at low frequency both in the cell-free system and in cultured virus. Direct comparison of viral and cell-free products revealed differences in the precision and selectivity of plus-strand initiation, suggesting that the cell free system lacks one or more essential replication components. These studies provide clues about mechanisms of plus-strand initiation and serve as a starting point for the development of more complex multicomponent cell-free systems. PMID- 9371585 TI - DNA-dependent transregulation by IE1 of Autographa californica nuclear polyhedrosis virus: IE1 domains required for transactivation and DNA binding. AB - IE1 is the principal early transregulator of Autographa californica multicapsid nuclear polyhedrosis virus (AcMNPV). The 582-residue protein stimulates viral transcription and binds as a dimer to 28-bp palindromic repeats (28-mers) comprising the AcMNPV homologous region (hr) transcription enhancers. To define IE1 domains responsible for hr-dependent transactivation, we first constructed a series of IE1 fusions to the DNA binding domain of the yeast GAL4 transactivator. In transfection assays, GAL4-IE1 fusions stimulated transcription from a TATA containing AcMNPV promoter only upon cis linkage to GAL4 DNA binding sites. IE1 N terminal residues 8 to 118 were sufficient for GAL4-binding-site-dependent transactivation. To identify IE1 residues required for hr interaction, we tested a series of IE1 mutations for 28-mer binding by using electrophoretic mobility shift assays. Deletion of IE1 residues other than the N-terminal transactivation domain eliminated 28-mer binding. Of 14 insertion mutations, only IE1(I425) and IE1(I553) failed to bind the 28-mer either as homodimers or as heterodimers with functional IE1. In contrast to insertion IE1(I425), IE1(I553) also failed to compete with wild-type IE1 for DNA binding and suggested a defect in oligomerization. Consistent with loss of oligomerization, substitutions within a hydrophobic repeat (residues 543 to 568) at the IE1 C terminus abolished 28-mer binding and demonstrated that this helix-loop-helix-like domain is required for DNA interaction. These data confirm that IE1 contains separable domains for transactivation and oligomerization-dependent DNA binding. Furthermore, they support a model wherein hr-mediated transactivation by IE1 involves sequence specific DNA binding that contributes to transcriptional stimulation by interaction with components of the basal transcription complex. PMID- 9371586 TI - Protein interactions during coronavirus assembly. AB - Coronaviruses assemble and obtain their envelope at membranes of the intermediate compartment between the endoplasmic reticulum and Golgi complex. Like other enveloped viruses, coronavirus assembly is presumably dependent on protein localization and protein-protein as well as protein-RNA interactions. We have used the bovine coronavirus (BCV) as a model to study interactions between the viral proteins in virus-infected cells that are important for coronavirus assembly. BCV is a prototype for the coronaviruses that express an additional major structural protein, the hemagglutinin esterase (HE), in addition to the spike (S) glycoprotein, membrane (M) glycoprotein, and nucleocapsid (N) protein. Complexes consisting of the M, S, and HE proteins were detected in virus-infected cells by coimmunoprecipitations. Kinetic analyses demonstrated that S protein and HE each quickly formed a complex with M protein after synthesis, whereas heterocomplexes consisting of all three proteins formed more slowly. The kinetics of HE biosynthesis revealed that the half-life of oligomerization was approximately 30 min, which correlated with the appearance of complexes consisting of M, HE, and S proteins, suggesting that oligomerization and/or conformational changes may be important for the S-M-HE protein complexes to form. Only HE dimers were found associated with the heterocomplexes consisting of all three proteins. S-M-HE protein complexes were detected prior to processing of the oligosaccharide chains on HE, indicating that these protein complexes formed in a premedial Golgi compartment before trimming of sugar chains. Transient coexpressions and double-labeling immunofluorescence demonstrated that HE and S proteins colocalized with M protein. This was further supported by coimmunoprecipitation of specific HE-M and S-M protein complexes from transfected cells, indicating that these proteins can form complexes in the absence of other viral proteins. PMID- 9371587 TI - The vaccinia virus I1 protein is essential for the assembly of mature virions. AB - The product of the vaccinia virus I1 gene was characterized biochemically and genetically. This 35-kDa protein is conserved in diverse members of the poxvirus family but shows no homology to nonviral proteins. We show that recombinant I1 binds to both single-stranded and double-stranded DNA in a sequence-nonspecific manner in an electrophoretic mobility shift assay. The protein is expressed at late times during infection, and approximately 700 copies are encapsidated within the virion core. To determine the role of the I1 protein during the viral life cycle, a inducible viral recombinant in which the I1 gene was placed under the regulation of the Escherichia coli lac operator/repressor was constructed. In the absence of isopropyl-beta-D-thiogalactopyranoside, plaque formation was abolished and yields of infectious, intracellular virus were dramatically reduced. Although all phases of gene expression and DNA replication proceeded normally during nonpermissive infections, no mature virions were produced. Electron microscopic analysis confirmed the absence of mature virion assembly but revealed that apparently normal immature virions accumulated. Thus, I1 is an encapsidated DNA binding protein required for the latest stages of vaccinia virion morphogenesis. PMID- 9371589 TI - Interaction between echovirus 7 and its receptor, decay-accelerating factor (CD55): evidence for a secondary cellular factor in A-particle formation. AB - Soluble forms of decay-accelerating factor (DAF) (CD55), the receptor for echovirus 7, were synthesized in the yeast Pichia pastoris. Purified recombinant protein containing SCR domains 2, 3, and 4, but lacking the serine/threonine rich region, was shown to block infection of susceptible cells by echovirus 7. In contrast to the situation with poliovirus and its receptor, the neutralization of echovirus 7 by soluble DAF was completely reversible and did not lead to the formation of 135S A-particles. Binding of virus to susceptible cells, by contrast, did lead to the formation of A particles, mainly from virus that had been internalized. The data suggest that a secondary factor(s) may contribute to A-particle formation and uncoating of echovirus 7. PMID- 9371588 TI - Distinct functions and requirements for the Cys-His boxes of the human immunodeficiency virus type 1 nucleocapsid protein during RNA encapsidation and replication. AB - The process of retroviral RNA encapsidation involves interaction between trans acting viral proteins and cis-acting RNA elements. The encapsidation signal on human immunodeficiency virus type 1 (HIV-1) RNA is a multipartite structure composed of functional stem-loop structures. The nucleocapsid (NC) domain of the Gag polyprotein precursor contains two copies of a Cys-His box motif that have been demonstrated to be important in RNA encapsidation. To further characterize the role of the Cys-His boxes of the HIV-1 NC protein in RNA encapsidation, the relative efficiency of RNA encapsidation for virus particles that contained mutations within the Cys-His boxes was measured. Mutations that disrupted the first Cys-His box of the NC protein resulted in virus particles that encapsidated genomic RNA less efficiently and subgenomic RNA more efficiently than did wild type virus. Mutations within the second Cys-His box did not significantly affect RNA encapsidation. In addition, a full complement of wild-type NC protein in virus particles is not required for efficient RNA encapsidation or virus replication. Finally, both Cys-His boxes of the NC protein play additional roles in virus replication. PMID- 9371590 TI - Alternative proteolytic processing of the arterivirus replicase ORF1a polyprotein: evidence that NSP2 acts as a cofactor for the NSP4 serine protease. AB - The C-terminal half of the replicase ORF1a polyprotein of the arterivirus equine arteritis virus is processed by a chymotrypsinlike serine protease (SP) (E. J. Snijder et al., J. Biol. Chem. 271:4864-4871, 1996) located in nonstructural protein 4 (nsp4). Three probable SP cleavage sites had previously been identified in the ORF1a protein. Their proteolysis explained the main processing products generated from the C-terminal part of the ORF1a protein in infected cells (E. J. Snijder et al., J. Virol. 68:5755-5764, 1994). By using sequence comparison, ORF1a expression systems, and site-directed mutagenesis, we have now identified two additional SP cleavage sites: Glu-1430 / Gly and Glu-1452 / Ser. This means that the ORF1a protein can be cleaved into eight processing end products: nsp1 to nsp8. By microsequence analysis of the nsp5 and nsp7 N termini, we have now formally confirmed the specificity of the SP for Glu / (Gly/Ser) substrates. Importantly, our studies revealed that the C-terminal half of the ORF1a protein (nsp3-8) can be processed by the SP following two alternative pathways, which appear to be mutually exclusive. In the majority of the nsp3-8 precursors the SP cleaves the nsp4/5 site, yielding nsp3-4 and nsp5-8. Subsequently, the latter product is cleaved at the nsp7/8 site only, whereas the newly identified nsp5/6 and nsp6/7 sites appear to be inaccessible to the protease. In the alternative proteolytic cascade, which is used at a low but significant level in infected cells, it is the nsp4/5 site which remains uncleaved, while the nsp5/6 and nsp6/7 sites are processed to yield a set of previously unnoticed processing products. Coexpression studies revealed that nsp3-8 has to interact with cleaved nsp2 to allow processing of the nsp4/5 junction, the first step of the major processing pathway. When the nsp2 cofactor is absent, the nsp4/5 site cannot be processed and nsp3-8 is processed following the alternative, minor pathway. PMID- 9371592 TI - Isolation of highly fusogenic variants of simian virus 5 from persistently infected cells that produce and respond to interferon. AB - A series of experiments were undertaken to examine how interferon and neutralizing antibodies influence the ability of simian virus 5 (SV5) (strain W3) to establish and maintain persistent infections in murine cells. In contrast to the rapid decline in SV5 protein synthesis observed in murine BALB/c fibroblasts (BF cells), which produce and respond to interferon, between 24 and 48 h postinfection there was no inhibition of virus protein synthesis in MSFI- cells, skin fibroblasts derived from alpha/beta-interferon receptor knockout BALB/c mice. Furthermore, the addition of anti-interferon antibodies to the culture medium of infected BF cells significantly reduced the observed decline in virus protein synthesis. Following infection of untreated BF cells, the majority replicated virus but survived the infection and eventually cleared the virus after 8 to 15 days. However, not all the cells were cured, and the cultures became persistently infected. Upon passage of persistently infected cultures, the virus fluxed between active and repressed states as a consequence of interferon production. This resulted in a balance being reached in which only 5 to 20% of the cells were infected at any one time. After 30 passages of the persistently infected cells, highly fusogenic virus variants arose (one of which was isolated and termed W3-f). W3-f remained as sensitive to interferon as the parental W3 isolate but, in the absence of interferon, spread much more rapidly than the parental W3 strain through BF cell monolayers. Sequence analysis revealed no deduced amino acid differences between the F proteins of W3 and W3-f. BF cell cultures persistently infected with W3-f were rapidly cleared of virus by the addition of virus-neutralizing antibodies to the culture medium. In contrast, neutralizing antibodies had little effect on the numbers of cells persistently infected with W3 over several passages. These results suggest that the ability of paramyxoviruses to cause cell-cell fusion may be selected for in vivo as a consequence of their adaptation to the interferon response rather than their need to escape from neutralizing antibodies. The significance of these observations with regard to persistent parainfluenza virus infections in vivo is further discussed. PMID- 9371591 TI - Early E-selectin, VCAM-1, ICAM-1, and late major histocompatibility complex antigen induction on human endothelial cells by flavivirus and comodulation of adhesion molecule expression by immune cytokines. AB - Expression of E-selectin (ELAM-1, CD62E) on human umbilical vein endothelial cells significantly increased 30 min postinfection with the flavivirus West Nile virus (WNV), was maximal by 2 h postinfection, and declined to baseline levels within 24 h. Expression of ICAM-1 (CD54) and VCAM-1 (CD106) was significantly increased by 2 h and maximal at 4 h after infection. P-selectin (CD62P) expression was unaffected by WNV. Upregulation occurred earlier than that caused by tumor necrosis factor alpha (TNF-alpha) or interleukin 1 (IL-1) and could not be inhibited by neutralizing TNF-alpha, IL-1alpha, or alpha/beta interferon (IFN alpha/beta) antibodies, suggesting a direct, virus-mediated phenomenon. TNF-alpha significantly enhanced WNV-induced increases in E-selectin, P-selectin, ICAM-1, and VCAM-1 expression, while IFN-gamma enhanced WNV-induced ICAM-1 expression. In contrast, IL-4 abrogated WNV-induced E-selectin expression increases but acted in synergy with WNV to increase P-selectin and VCAM-1 expression. WNV increased the expression of class I and II major histocompatibility complex antigens (MHC-I and MHC-II, respectively) at 24 and 72 h, respectively. IFN-gamma, TNF-alpha, or IL-1 acted in synergy with WNV to produce greater increases in MHC-I expression than WNV or cytokines alone, while IFN-alpha/beta or IL-4 had no effect. MHC-II induction in cytokine-treated, WNV-infected cells was similar to that caused by cytokines alone. Neutralizing IFN-alpha/beta antibody inhibited WNV-induced MHC-I expression by 30% at 24 h and by 100% by 72 h. The differential kinetics of modulation suggest sequential adhesion of leukocyte subpopulations to infected endothelial cells, which may be important in initial viral spread in vivo. PMID- 9371593 TI - Different mechanisms contribute to the E2-mediated transcriptional repression of human papillomavirus type 18 viral oncogenes. AB - Transcription of the human papillomavirus type 18 (HPV18) E6 and E7 oncogenes is repressed by the viral E2 protein. In C33 cells, we have previously shown that of the four E2 binding sites (E2 BS) present in the HPV18 long control region (LCR), only the binding site adjacent to the TATA box (E2 BS 1) was involved in E2 mediated repression. In the present study, we sought to determine whether this phenomenon was conserved in other cell lines. We first showed that all three E2 BS proximal to the P105 promoter were required for full repression of its activity in HeLa and HaCaT cells. Repression by E2 at E2 BS 2 occurred through the displacement of Sp1. Second, a truncated E2 product, lacking the N-terminal transactivation domain, repressed transcription more efficiently than the full length protein. Repression was abolished when the N-terminal domain of E2 was replaced by the activation domain of VP16. The VP16-E2 chimeric protein could activate transcription from an LCR mutated in its TATA box. DNA-protein binding studies showed that E2 associates with its four binding sites in the LCR with similar affinities. However, challenge of such complexes with excess binding sites demonstrated that interaction with E2 BS 4 was the most stable while interaction with E2 BS 1 was the least stable. Furthermore, complexes with the full-length E2 were less stable than those formed with the N-terminally truncated protein. PMID- 9371594 TI - A short linear sequence in the pre-S domain of the large hepatitis B virus envelope protein required for virion formation. AB - Envelopment of the hepatitis B virus (HBV) nucleocapsid depends on the large envelope protein L, which is expressed as a transmembrane polypeptide at the endoplasmic reticulum membrane. Previous studies demonstrated that the cytosolic exposure of the N-terminal pre-S domain (174 amino acids) of L was required for virion formation. N-terminal truncations of L up to Arg 103 were tolerated. To map sites in the remaining C-terminal part of pre-S important for virion morphogenesis, a series of 11 L mutants with linker substitutions between Asn 98 and Pro 171 was generated. The mutants formed stable proteins and were secreted in transfected cell cultures, probably as components of subviral hepatitis B surface antigen particles. All four constructs with mutations between Asn 98 and Thr 125 were unable to complement in trans the block in virion formation of an L negative HBV genome in cotransfected HuH7 cells. These mutants had a transdominant negative effect on virus yield in cotransfections with the wild type HBV genome. In contrast, all seven mutants with substitutions downstream of Ser 124 were able to envelop the nucleocapsid and to secrete HBV. The sequence between Arg 103 and Ser 124 is highly conserved among different HBV isolates and also between HBV and the woodchuck hepatitis virus. Point mutations in this region introducing alanine residues at conserved positions blocked virion formation, in contrast to mutations at nonconserved residues. These results demonstrate that the pre-S sequence between Arg 103 and Ser 124 has an important function in HBV morphogenesis. PMID- 9371595 TI - Human immunodeficiency virus type 1 Vif protein binds to the Pr55Gag precursor. AB - The Vif protein of human immunodeficiency virus type 1 is required for productive replication in peripheral blood lymphocytes. Previous reports suggest that vif deleted viruses are limited in replication because of a defect in the late steps of the virus life cycle. One of the remaining questions is to determine whether the functional role of Vif involves a specific interaction with virus core proteins. In this study, we demonstrate a direct interaction between Vif and the Pr55Gag precursor in vitro as well as in infected cells. No interaction is observed between Vif and the mature capsid protein. The Pr55Gag-Vif interaction is detected (i) in the glutathione S-transferase system, with in vitro-translated proteins demonstrating a critical role of the NC p7 domain of the Gag precursor; (ii) with proteins expressed in infected cells; and (iii) by coimmunoprecipitation experiments. Deletion of the C-terminal 22 amino acids of Vif abolishes its interaction with the Pr55Gag precursor. Furthermore, point mutations in the C-terminal domain of Vif which have been previously shown to abolish virus infectivity and binding to cell membranes dramatically decrease the Gag-Vif interaction. These results suggest that the interaction between Vif and the pr55Gag precursor is a critical determinant of Vif function. PMID- 9371597 TI - Repression of human immunodeficiency virus type 1 through the novel cooperation of human factors YY1 and LSF. AB - A subpopulation of stably infected CD4+ cells capable of producing virus upon stimulation has been identified in human immunodeficiency virus (HIV)-positive individuals (T.-W. Chun, D. Finzi, J. Margolick, K. Chadwick, D. Schwartz, and R. F. Siliciano, Nat. Med. 1:1284-1290, 1995). Few host factors that directly limit HIV-1 transcription and could support this state of nonproductive HIV-1 infection have been described. YY1, a widely distributed human transcription factor, is known to inhibit HIV-1 long terminal repeat (LTR) transcription and virus production. LSF (also known as LBP-1, UBP, and CP-2) has been shown to repress LTR transcription in vitro, but transient expression of LSF has no effect on LTR activity in vivo. We report that both YY1 and LSF participate in the formation of a complex that recognizes the initiation region of the HIV-1 LTR. Further, we have found that these factors cooperate in the repression of LTR expression and viral replication. This cooperative function may account for the divergent effects of LSF previously observed in vitro and in vivo. Thus, the cooperation of two general cellular transcription factors may allow for the selective downregulation of HIV transcription. Through this mechanism of gene regulation, YY1 and LSF could contribute to the establishment and maintenance of a population of cells stably but nonproductively infected with HIV-1. PMID- 9371596 TI - Differential regulation of the pre-C and pregenomic promoters of human hepatitis B virus by members of the nuclear receptor superfamily. AB - Synthesis of the pre-C and pregenomic RNAs of human hepatitis B virus (HBV) is directed by two overlapping yet separate promoters (X. Yu and J. E. Mertz, J. Virol. 70:8719-8726, 1996). Previously, we reported the identification of a binding site for the nuclear receptor hepatocyte nuclear factor 4 (HNF4) spanning the TATA box-like sequence of the pre-C promoter. This HNF4-binding site consists of an imperfect direct repeat of the consensus half-site sequence 5'-AGGTCA-3' separated by one nucleotide; i.e., it is a DR1 hormone response element (HRE). We show here that other receptors, including chicken ovalbumin upstream promoter transcription factor 1 (COUP-TF1), human testicular receptor 2 (TR2), and peroxisome proliferator-activated receptors (PPARs) as heterodimers with retinoid X receptors (RXRs), can also specifically bind this DR1 HRE. Synthesis of the pre C and pregenomic RNAs was affected both in transfected hepatoma cells and in a cell-free transcription system by the binding of factors to this DR1 HRE. Interestingly, whereas some members of the hormone receptor superfamily differentially repressed synthesis of the pre-C RNA (e.g., HNF4 and TR2) or activated synthesis of the pregenomic RNA (e.g., PPARgamma-RXRalpha), other members (e.g., COUP-TF1) coordinately repressed synthesis of both the pre-C and pregenomic RNAs. Thus, HBV likely regulates its expression and replication in part via this DR1 HRE. These findings indicate that appropriate ligands to nuclear receptors may be useful in the treatment of HBV infection. PMID- 9371598 TI - Variable regions A and B in the envelope glycoproteins of feline leukemia virus subgroup B and amphotropic murine leukemia virus interact with discrete receptor domains. AB - The surface (SU) envelope glycoproteins of feline leukemia virus subgroup B (FeLV B) and amphotropic murine leukemia virus (A-MLV) are highly related, even in the variable regions VRA and VRB that have been shown to be required for receptor recognition. However, FeLV-B and A-MLV use different sodium-dependent phosphate symporters, Pit1 and Pit2, respectively, as receptors for infection. Pit1 and Pit2 are predicted to have 10 membrane-spanning domains and five extracellular loops. The close relationship of the retroviral envelopes enabled us to generate pseudotype virions carrying chimeric FeLV-B/A-MLV envelope glycoproteins. We found that some of the pseudotype viruses could not use Pit1 or Pit2 proteins but could efficiently utilize specific chimeric Pit1/Pit2 proteins as receptors. By studying Mus dunni tail fibroblasts expressing chimeric Pit1/Pit2 proteins and pseudotype virions carrying chimeric FeLV-B/A-MLV envelopes, we show that FeLV-B and A-MLV VRA and VRB interact in a modular manner with specific receptor domains. Our results suggest that FeLV-B VRA interacts with Pit1 extracellular loops 4 and 5 and that residues Phe-60 and Pro-61 of FeLV-B VRA are essential for receptor choice. However, this interaction is insufficient for infection, and an additional interaction between FeLV-B VRB and Pit1 loop 2 is essential. Similarly, A-MLV infection requires interaction of A-MLV VRA with Pit2 loops 4 and 5 and VRB with Pit2 loop 2, with residues Tyr-60 and Val-61 of A-MLV VRA being critical for receptor recognition. Together, our results suggest that FeLV B and A-MLV infections require two major discrete interactions between the viral SU envelope glycoproteins and their respective receptors. We propose a common two step mechanism for interaction between retroviral envelope glycoproteins and cell surface receptors. PMID- 9371599 TI - Lack of effect of antiviral therapy in nondividing hepatocyte cultures on the closed circular DNA of woodchuck hepatitis virus. AB - The template for synthesis of hepadnaviral RNAs is a covalently closed circular (ccc) DNA located in the nucleus of the infected hepatocyte. Hepatocytes are normally long-lived and nondividing, and antiviral therapies in chronically infected individuals face the problem of eliminating not only the replicative forms of viral DNA found in the cytoplasm but also the cccDNA from the nucleus. Because cccDNA does not replicate semiconservatively, it is not an obvious target for antiviral therapy. However, elimination of cccDNA might be facilitated if its half-life were short in comparison to the generation time of hepatocytes and if new cccDNA formation were effectively blocked. We have therefore measured cccDNA levels in woodchuck hepatocyte cultures following in vitro infection with woodchuck hepatitis virus and treatment with inhibitors of viral DNA synthesis. The viral reverse transcriptase inhibitors lamivudine (3TC) [(-)-beta-L-2',3' dideoxy-3'-thiacytidine), FTC (5-fluoro-2',3'-dideoxy-3'-thiacytidine) and ddC (2',3'-dideoxycytidine) were added to the cultures beginning at 4 days postinfection. Treatment for up to 36 days with 3TC reduced the amount of cccDNA in the cultures not more than twofold compared to that of an untreated control. Treatment with ddC for 36 days and with FTC for 12 days resulted in effects similar to that of treatment with 3TC. Moreover, the declines in cccDNA appeared to reflect the loss of hepatocytes from the cultures rather than of cccDNA from hepatocytes. These results emphasize the important role of the longevity of the infected hepatocytes in the persistence of an infection. PMID- 9371600 TI - Mutational analysis of the hepatitis C virus RNA helicase. AB - The carboxyl-terminal three-fourths of the hepatitis C virus (HCV) NS3 protein has been shown to possess an RNA helicase activity, typical of members of the DEAD box family of RNA helicases. In addition, the NS3 protein contains four amino acid motifs conserved in DEAD box proteins. In order to inspect the roles of individual amino acid residues in the four conserved motifs (AXXXXGKS, DECH, TAT, and QRRGRTGR) of the NS3 protein, mutational analysis was used in this study. Thirteen mutant proteins were constructed, and their biochemical activities were examined. Lys1235 in the AXXXXGKS motif was important for basal nucleoside triphosphatase (NTPase) activity in the absence of polynucleotide cofactor. A serine in the X position of the DEXH motif disrupted the NTPase and RNA helicase activities. Alanine substitution at His1318 of the DEXH motif made the protein possess high NTPase activity. In addition, we now report inhibition of NTPase activity of NS3 by polynucleotide cofactor. Gln1486 was indispensable for the enzyme activity, and this residue represents a distinguishing feature between DEAD box and DEXH proteins. There are four Arg residues in the QRRGRTGR motif of the HCV NS3 protein, and the second, Arg1488, was important for RNA binding and enzyme activity, even though it is less well conserved than other Arg residues. Arg1490 and Arg1493 were essential for the enzymatic activity. As the various enzymatic activities were altered by mutation, the enzyme characteristics were also changed. PMID- 9371601 TI - The DnaJ domain of polyomavirus large T antigen is required to regulate Rb family tumor suppressor function. AB - Tumor suppressors of the retinoblastoma susceptibility gene family regulate cell growth and differentiation. Polyomavirus large T antigens (large T) bind Rb family members and block their function. Mutations of large T sequences conserved with the DnaJ family affect large T binding to a cellular DnaK, heat shock protein 70. The same mutations abolish large T activation of E2F-containing promoters and Rb binding-dependent large T activation of cell cycle progression. Cotransfection of a cellular DnaJ domain blocks wild-type large T action, showing that the connection between the chaperone system and tumor suppressors is direct. Although they are inactive in assays dependent on Rb family binding, mutants in the J region retain the ability to associate with pRb, p107, and p130. This suggests that binding of Rb family members by large T is not sufficient for their inactivation and that a functional J domain is required as well. This work connects the DnaJ and DnaK molecular chaperones to regulation of tumor suppressors by polyomavirus large T. PMID- 9371604 TI - Dual topology of the large envelope protein of duck hepatitis B virus: determinants preventing pre-S translocation and glycosylation. AB - The biosynthesis and topology of the large envelope protein (L protein) of hepadnaviruses was investigated using the duck hepatitis B virus (DHBV) model, which also allows the study of hepadnavirus morphogenesis in experimentally infected hepatocytes. Results from proteolysis of virus particles and from the analysis of topology and posttranslational modification of L chains synthesized in vivo or in a cell-free system both support the presence of a mixed population of L-protein molecules with their N-terminal pre-S domain located either inside or outside the virus particle. During L biosynthesis and DHBV morphogenesis, pre S, together with the neighboring transmembrane domain (TM-I), initially remained cytoplasmically disposed and was translocated only posttranslationally. Delayed pre-S translocation into a post-endoplasmic reticulum compartment is also indicated by the absence of glycosylation at a modification-competent pre-S glycosylation site. Major features of L-protein biosynthesis and of the resulting dual topology appear to be conserved between avian and mammalian hepadnaviruses, supporting the model that pre-S domains function in part either as an internal matrix for capsid envelopment or externally as a ligand for cellular receptor binding. However, differences in the mechanisms controlling pre-S translocation were revealed by the results of mutational analyses identifying and characterizing cis-acting determinants in pre-S that delay its cotranslational translocation. Our data from DHBV demonstrate the negative influence of a cluster of positively charged amino acid residues next to TM-I, a motif that is conserved among the avian but absent from mammalian hepadnaviruses. Additional control elements, which are apparently shared between both virus groups and which may serve in chaperone binding, were mapped by deletion analysis in the central part of pre-S. PMID- 9371603 TI - The function of the spike protein of mouse hepatitis virus strain A59 can be studied on virus-like particles: cleavage is not required for infectivity. AB - The spike protein (S) of the murine coronavirus mouse hepatitis virus strain A59 (MHV-A59) induces both virus-to-cell fusion during infection and syncytium formation. Thus far, only syncytium formation could be studied after transient expression of S. We have recently described a system in which viral infectivity is mimicked by using virus-like particles (VLPs) and reporter defective interfering (DI) RNAs (E. C. W. Bos, W. Luytjes, H. Van der Meulen, H. K. Koerten, and W. J. M. Spaan, Virology 218:52-60, 1996). Production of VLPs of MHV A59 was shown to be dependent on the expression of M and E. We now show in several ways that the infectivity of VLPs is dependent on S. Infectivity was lost when spikeless VLPs were produced. Infectivity was blocked upon treatment of the VLPs with MHV-A59-neutralizing anti-S monoclonal antibody (MAb) A2.3 but not with nonneutralizing anti-S MAb A1.4. When the target cells were incubated with antireceptor MAb CC1, which blocks MHV-A59 infection, VLPs did not infect the target cells. Thus, S-mediated VLP infectivity resembles MHV-A59 infectivity. The system can be used to identify domains in S that are essential for infectivity. As a first application, we investigated the requirements of cleavage of S for the infectivity of MHV-A59. We inserted three mutant S proteins that were previously shown to be uncleaved (E. C. W. Bos, L. Heijnen, W. Luytjes, and W. J. M. Spaan, Virology 214:453-463, 1995) into the VLPs. Here we show that cleavage of the spike protein of MHV-A59 is not required for infectivity. PMID- 9371602 TI - Direct interaction of hepatitis C virus core protein with the cellular lymphotoxin-beta receptor modulates the signal pathway of the lymphotoxin-beta receptor. AB - Previous studies suggest that the core protein of hepatitis C virus (HCV) has a pleiotropic function in the replication cycle of the virus. To understand the role of this protein in HCV pathogenesis, we used a yeast two-hybrid protein interaction cloning system to search for cellular proteins physically interacting with the HCV core protein. One such cellular gene was isolated and characterized as the gene encoding the lymphotoxin-beta receptor (LT-betaR). In vitro binding analysis demonstrated that the HCV core protein binds to the C-terminal 98 amino acids within the intracellular domain of the LT-betaR that is involved in signal transduction, although the binding affinity of the full-length HCV core protein was weaker than that of its C-terminally truncated form. Our results also indicated that the N-terminal 40-amino-acid segment of the HCV core protein was sufficient for interaction with LT-betaR and that the core protein could form complexes with the oligomeric form of the intracellular domain of LT-betaR, which is a prerequisite for downstream signaling of this receptor. Similar to other members of the tumor necrosis factor (TNF) receptor superfamily, LT-betaR is involved in the cytotoxic effect of the signaling pathway, and thus we have elucidated the biological consequence of interaction between the HCV core protein and LT-betaR. Our results indicated that in the presence of the synergizing agent gamma interferon, the HCV core protein enhances the cytotoxic effects of recombinant forms of LT-betaR ligand in HeLa cells but not in hepatoma cells. Furthermore, this enhancement of the cytolytic activity was cytokine specific, since in the presence of cycloheximide, the expression of the HCV core protein did not elicit an increase in the cytolytic activity of TNF in both HeLa and hepatoma cells. In summary, the HCV core protein can associate with LT-betaR, and this protein-protein interaction has a modulatory effect on the signaling pathway of LT-betaR in certain cell types. Given the known roles of LT-betaR/LT alpha1,beta2 receptor-ligand interactions in the normal development of peripheral lymphoid organs and in triggering cytolytic activity and NF-kappaB activation in certain cell types, our finding implies that the HCV core protein may aggravate these biological functions of LT-betaR, resulting in pathogenesis in HCV-infected cells. PMID- 9371605 TI - The herpes simplex virus virulence factor ICP34.5 and the cellular protein MyD116 complex with proliferating cell nuclear antigen through the 63-amino-acid domain conserved in ICP34.5, MyD116, and GADD34. AB - The herpes simplex virus (HSV) virulence factor ICP34.5, the mouse myeloid differentiation protein MyD116, and the hamster growth arrest and DNA damage protein GADD34 share a 63-amino-acid carboxyl domain which has significant homologies to otherwise divergent proteins. Here we report that both ICP34.5 and its cellular homolog MyD116 complex through the conserved domain with proliferating cell nuclear antigen. In addition, HSV infection induces a novel 70 kDa cellular protein detectable by antisera to both ICP34.5 and GADD34, demonstrating that this novel protein possesses homology with the 63-amino-acid conserved domain. PMID- 9371606 TI - Alveolar macrophages regulate the induction of primary cytotoxic T-lymphocyte responses during influenza virus infection. AB - Virus-specific cytotoxic T lymphocytes (CTL) are thought to be responsible for the eradication of respiratory influenza virus infections by direct cytolysis of virus-infected epithelial cells. In this study, we provide evidence for a role for alveolar macrophages (AM) in the regulation of pulmonary virus-specific CTL responses. Prior to infection with influenza virus, AM were selectively eliminated in vivo with a liposome-mediated depletion technique, and virus specific CTL activities of lung and mediastinal lymph node (MLN) cells were assayed ex vivo and compared with those for normal mice. AM depletion resulted in increased primary CTL responses and changed the kinetics of the CTL response. Flow cytometric analysis of lung and MLN cells showed that the percentage of CD8+ cells was not altered after AM depletion and that lung cells from AM-depleted mice had an increased capacity to lyse virus-infected cells. Upon restimulation in vitro, virus-specific CTL activity in lung cells of normal mice was similar to that in lung cells of AM-depleted mice. Furthermore, elimination of AM resulted in increased virus titers in the lung, but virus clearance as a function of time was not affected. Our results show that AM regulate virus-specific CTL responses during respiratory influenza virus infection by removing viral particles, by downregulating the priming and activity of CTL in MLN cells, and by inhibiting the expansion of virus-specific CTL in the lung. PMID- 9371607 TI - Rotavirus nonstructural glycoprotein NSP4 alters plasma membrane permeability in mammalian cells. AB - The endoplasmic reticulum-localized transmembrane glycoprotein NSP4 of rotavirus is a key protein involved in rotavirus cytopathology. We have used a dual recombinant vaccinia virus system to express NSP4 in monkey kidney epithelial cells at a level comparable to that observed during rotavirus infection. Expression of NSP4 results in loss of plasma membrane integrity, which can be demonstrated by release of both 51Cr and lactate dehydrogenase into the medium. The cytotoxic behavior of NSP4 is dose dependent, and morphological analysis reveals gross changes to cell ultrastructure, indicative of cell death. Thus, intracellular expression of a single rotavirus protein which localizes to the endoplasmic reticulum membrane has profound effects on the stability of the plasma membrane and cell viability. Analysis of NSP4 deletion mutants indicates that a membrane-proximal region located within the cytoplasmic domain may mediate cytotoxicity. PMID- 9371608 TI - Increased probability of expression from modified retroviral vectors in embryonal stem cells and embryonal carcinoma cells. AB - Gene expression from the Moloney murine leukemia retrovirus (Mo-MuLV) is highly restricted in embryonic carcinoma (EC) and embryonic stem (ES) cells. We compared levels of expression in PA317 fibroblasts, F9 (EC) cells, and CCE (ES) cells by Mo-MuLV-based vectors and vectors based on our previously reported MND backbone, which has alterations to address three viral elements implicated as repressors of expression by Mo-MuLV: the enhancer, the primer binding site, and the negative control region. Expression was evaluated with three reporter genes, the chloramphenicol acetyltransferase (CAT) gene, whose expression was measured by enzymatic assay and by Northern blotting; a truncated nerve growth factor receptor (tNGFR), whose expression was measured by fluorescence-activated cell sorting (FACS) as a cell surface protein; and the enhanced green fluorescent protein (EGFP), whose expression was measured intracellularly by flow cytometry. We found significantly higher levels of CAT activity (5- to 300-fold) and greater quantities of vector-specific transcripts in ES and EC cells transduced with the modified MND-CAT-SN vector than in those transduced with L-CAT-SN. Northern blot analysis indicated that long terminal repeat transcripts from MND-CAT-SN are >80 times more abundant than the L-CAT-SN transcripts. FACS analysis of tNGFR expression from a pair of vectors, L-tNGFR-SN and MND-tNGFR-SN, indicated that only 1.04% of the CCE cells containing the L-tNGFR-SN vector expressed the cell surface reporter, while the MND-tNGFR-SN vector drove expression in 99.54% of the CCE cells. Of the F9 cells containing the L-tNGFR-SN vector, 13.32% expressed tNGFR, while 99.89% of the F9 cells transduced with MND-tNGFR-SN showed expression. Essentially identical results were produced with an analogous pair of vectors encoding EGFP. In unselected pools of F9 cells 48 h posttransduction, the L-EGFP-SN vector drove expression in only 5% of the population while the MND-EGFP SN vector drove expression in 88% of the cells. After more than 3 weeks in culture without selection, the proportion of cells showing expression from L-EGFP SN decreased slightly to 3% while expression from the MND-EGFP-SN vector persisted in 80% of the cells. Interestingly, in the few ES and EC cells which did show expression from the L-tNGFR-SN or L-EGFP-SN vectors, the magnitude of reporter expression was similar to that from the MND-tNGFR-SN or MND-EGFP-SN vector in nearly all cells, suggesting that the MND vectors are far less susceptible to position-dependent variegation of expression than are the Mo-MuLV based vectors. Therefore, the modified retroviral vector, MND, achieves higher net levels of expression due to a greater frequency of expression, which may be useful for the expression of exogenous genes in EC and ES cells. PMID- 9371609 TI - Identification of the V1 region as a linear neutralizing epitope of the simian immunodeficiency virus SIVmac envelope glycoprotein. AB - The sequence variability of viral structure polypeptides has been associated with immune escape mechanisms. The V1 region of simian immunodeficiency virus (SIV) is a highly variable region of the SIVmac env gene. Here, we describe the V1 region as a linear neutralizing epitope. V1 region-specific neutralizing antibodies (NAb) were first demonstrated in a rabbit infected with a recombinant vaccinia virus carrying the env gene of human immunodeficiency virus type 2 strain ben (HIV-2ben). Since we detected in this animal V1 region-specific NAb that were able to neutralize not only human immunodeficiency virus type 2 but also SIVmac32H, we investigated whether a similar immune response is evoked in macaques (Macaca mulatta) either infected with SIVmac or immunized with the external glycoprotein (gp130) of the same virus. Distinctly lower NAb titers were found in the SIVmac-infected animals than in the gp130-immunized macaques. Since the NAb titers in both groups were high enough for competition experiments, we used five overlapping peptides encompassing the whole V1 region for a detailed identification of the epitope. In each of the 12 macaques investigated, we detected a high level of NAb reacting with at least one peptide located in the central part of the V1 region. The relatively high degree of divergence, especially within the central part of the V1 region, which characterized the evolution of the retroviral sequences from the original inoculum in the infected macaques suggests the development of escape mutants. Furthermore, 3 of 12 animals developed NAb directed against the amino-terminal end of the V1 region epitope. Sequence analysis, however, revealed relatively low levels of genetic drift and genetic variability within this part of the V1 region. The induction of V1 env specific NAb not only in gp130-immunized macaques but also in SIVmac-infected animals in combination with the increased genetic variability of this region in vivo indicates a marked biological significance of this epitope for the virus. PMID- 9371610 TI - The 3' untranslated region of the B19 parvovirus capsid protein mRNAs inhibits its own mRNA translation in nonpermissive cells. AB - Although parvoviruses are found throughout the animal kingdom, only the human pathogenic B19 virus has so far been shown to possess a limited host range, with erythroid progenitor cells as the main target cells supporting B19 propagation. The underlying mechanism of such erythroid tropism is still unexplained. Synthesis of the NS1 nonstructural protein occurs in permissive and nonpermissive cells, such as megakaryocytes, whereas synthesis of the VP1 and VP2 capsid proteins seems to be restricted to burst-forming units and CFU of erythroid cells. In nonpermissive cells, the NS1 protein is overexpressed and the NS1 RNAs are the predominant RNA species. However, the VP1 and VP2 proteins are not detectable, although the corresponding mRNAs are synthesized. Since all transcripts have part of the 5' untranslated region (5' UTR) in common but distinct 3' UTRs characterizing the nonstructural- and structural-protein mRNAs, we investigated, in transient transfection assays, the possible involvement of the 3' UTR of the capsid protein mRNAs in VP1 and VP2 protein synthesis in nonpermissive Cos cells. The results showed that (i) the 3' UTR of mRNAs coding for the capsid proteins repressed VP1 and VP2 protein synthesis, (ii) the 3' UTR did not affect nuclear export or mRNA stability, and (iii) mRNAs bearing the 3' UTR of the capsid protein mRNAs did not associate with ribosomes at all. Taken together, these results indicate that in nonpermissive cells, the 3' UTR of the capsid protein mRNAs represses capsid protein synthesis at the translational level by inhibiting ribosome loading. PMID- 9371611 TI - Genetic dissection of interaction between poliovirus 3D polymerase and viral protein 3AB. AB - Poliovirus RNA-dependent RNA polymerase 3D and viral protein 3AB are both thought to be required for the initiation of RNA synthesis. These two proteins physically associate with each other and with viral RNA replication complexes found on virus induced membranes in infected cells. An understanding of the interface between 3D and 3AB would provide a first step in visualizing the architecture of the multiprotein complex that is assembled during poliovirus infection to replicate and package the viral RNA genome. The identification of mutations in 3D that diminish 3D-3AB interactions without affecting other functions of 3D polymerase is needed to study the function of the 3D-3AB interaction in infected cells. We describe the use of the yeast two-hybrid system to isolate and characterize mutations in 3D polymerase that cause it to interact less efficiently with 3AB than wild-type polymerase. One mutation, a substitution of leucine for valine at position 391 (V391L), resulted in a 3AB-specific interaction defect in the two hybrid system, causing a reduction in the interaction of 3D polymerase with 3AB but not with another viral protein or a host protein tested. In vitro, purified 3D-V391L polymerase bound to membrane-associated 3AB with reduced affinity. Poliovirus that contained the 3D-V391L mutation was temperature sensitive, displaying a pronounced conditional defect in RNA synthesis. We conclude that interaction between 3AB and 3D or 3D-containing polypeptides plays a role in RNA synthesis during poliovirus infection. PMID- 9371612 TI - The murine coronavirus mouse hepatitis virus strain A59 from persistently infected murine cells exhibits an extended host range. AB - In murine 17 Cl 1 cells persistently infected with murine coronavirus mouse hepatitis virus strain A59 (MHV-A59), expression of the virus receptor glycoprotein MHVR was markedly reduced (S. G. Sawicki, J. H. Lu, and K. V. Holmes, J. Virol. 69:5535-5543, 1995). Virus isolated from passage 600 of the persistently infected cells made smaller plaques on 17 Cl 1 cells than did MHV A59. Unlike the parental MHV-A59, this variant virus also infected the BHK-21 (BHK) line of hamster cells. Virus plaque purified on BHK cells (MHV/BHK) grew more slowly in murine cells than did MHV-A59, and the rate of viral RNA synthesis was lower and the development of the viral nucleocapsid (N) protein was slower than those of MHV-A59. MHV/BHK was 100-fold more resistant to neutralization with the purified soluble recombinant MHV receptor glycoprotein (sMHVR) than was MHV A59. Pretreatment of 17 Cl 1 cells with anti-MHVR monoclonal antibody CC1 protected the cells from infection with MHV-A59 but only partially protected them from infection with MHV/BHK. Thus, although MHV/BHK could still utilize MHVR as a receptor, its interactions with the receptor were significantly different from those of MHV-A59. To determine whether a hemagglutinin esterase (HE) glycoprotein that could bind the virions to 9-O-acetylated neuraminic acid moieties on the cell surface was expressed by MHV/BHK, an in situ esterase assay was used. No expression of HE activity was detected in 17 Cl 1 cells infected with MHV/BHK, suggesting that this virus, like MHV-A59, bound to cell membranes via its S glycoprotein. MHV/BHK was able to infect cell lines from many mammalian species, including murine (17 Cl 1), hamster (BHK), feline (Fcwf), bovine (MDBK), rat (RIE), monkey (Vero), and human (L132 and HeLa) cell lines. MHV/BHK could not infect dog kidney (MDCK I) or swine testis (ST) cell lines. Thus, in persistently infected murine cell lines that express very low levels of virus receptor MHVR and which also have and may express alternative virus receptors of lesser efficiency, there is a strong selective advantage for virus with altered interactions with receptor (D. S. Chen, M. Asanaka, F. S. Chen, J. E. Shively, and M. M. C. Lai, J. Virol. 71:1688-1691, 1997; D. S. Chen, M. Asanaka, K. Yokomori, F.-I. Wang, S. B. Hwang, H.-P. Li, and M. M. C. Lai, Proc. Natl. Acad. Sci. USA 92:12095-12099, 1995; P. Nedellec, G. S. Dveksler, E. Daniels, C. Turbide, B. Chow, A. A. Basile, K. V. Holmes, and N. Beauchemin, J. Virol. 68:4525-4537, 1994). Possibly, in coronavirus-infected animals, replication of the virus in tissues that express low levels of receptor might also select viruses with altered receptor recognition and extended host range. PMID- 9371613 TI - The extent of early viral replication is a critical determinant of the natural history of simian immunodeficiency virus infection. AB - Different patterns of viral replication correlate with the natural history of disease progression in humans and macaques infected with human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV), respectively. However, the viral and host factors influencing these patterns of viral replication in vivo are poorly understood. We intensively studied viral replication in macaques receiving identical inocula of SIV. Marked differences in viral replication patterns were apparent within the first week following inoculation, a time prior to the development of measurable specific immune effector responses to viral antigens. Plasma viral RNA levels measured on day 7 postinoculation correlated with levels measured in the postacute phase of infection. Differences in the susceptibility of host cells from different animals to in vitro SIV infection correlated with the permissiveness of the animals for early in vivo viral replication and hence with the postacute set point level of plasma viremia. These results suggest that host factors that exert their effects prior to full development of specific immune responses are critical in establishing the in vivo viral replication pattern and associated clinical course in subjects infected with SIV and, by extension, with HIV-1. PMID- 9371614 TI - Cell culture adaptation of Puumala hantavirus changes the infectivity for its natural reservoir, Clethrionomys glareolus, and leads to accumulation of mutants with altered genomic RNA S segment. AB - This paper reports the establishment of a model for hantavirus host adaptation. Wild-type (wt) (bank vole-passaged) and Vero E6 cell-cultured variants of Puumala virus strain Kazan were analyzed for their virologic and genetic properties. The wt variant was well adapted for reproduction in bank voles but not in cell culture, while the Vero E6 strains replicated to much higher efficiency in cell culture but did not reproducibly infect bank voles. Comparison of the consensus sequences of the respective viral genomes revealed no differences in the coding region of the S gene. However, the noncoding regions of the S gene were found to be different at positions 26 and 1577. In one additional and independent adaptation experiment, all analyzed cDNA clones from the Vero E6-adapted variant were found to carry substitutions at position 1580 of the S segment, just 3 nucleotides downstream of the mutation observed in the first adaptation. No differences were found in the consensus sequences of the entire M segments from the wt and the Vero E6-adapted variants. The results indicated different impacts of the S and the M genomic segments for the adaptation process and selective advantages for the variants that carried altered noncoding sequences of the S segment. We conclude that the isolation in cell culture resulted in a phenotypically and genotypically altered hantavirus. PMID- 9371615 TI - Infectivity enhancement by human immunodeficiency virus type 1 Nef is independent of its association with a cellular serine/threonine kinase. AB - Nef proteins from human immunodeficiency virus type 1 isolate SF2 (HIV-1SF2) and simian immunodeficiency virus isolate mac239 (SIVmac239) have been found to associate with a cellular serine/threonine kinase designated NAK. We have recently shown that the association of Nef with NAK is isolate dependent. To identify the structural basis for Nef-kinase association, several chimeric molecules were constructed between SF2 Nef (binding NAK) and 233 Nef (a primary isolate not binding NAK) and stably expressed in HuT-78 human T cells via retrovirus-mediated gene transfer. The Nef 233/SF2/SF2 chimera in which the N terminal 37 amino acids of SF2 Nef were replaced by those of 233 Nef showed the same ability as SF2 Nef to bind NAK. The Nef 233/SF2/233 chimera in which the N terminal 37 amino acids and the C-terminal 72 amino acids of SF2 Nef were replaced by corresponding sequences from 233 Nef completely lost the ability to associate with the kinase activity. Furthermore, replacement of the C-terminal 72 amino acids of 233 Nef with the equivalent SF2 sequence (chimera 233/233/SF2) fully restored kinase association to 233 Nef. These results suggest that (i) the core of Nef is not sufficient for NAK binding, (ii) the C terminus of SF2 Nef contains structural determinants important for association with NAK, and (iii) the failure of 233 Nef to bind NAK is due to a defect in its C terminus. Taking advantage of the C terminus of 233 Nef being nonfunctional and using an infectious clone of HIV-1SF2, we show that association with NAK is not required for Nef-mediated infectivity enhancement. While the strong and reproducible association of some Nef isolates with NAK has been clearly established, the role of NAK in Nef function remains to be fully elucidated. PMID- 9371616 TI - Activation of the T-cell receptor signaling pathway by Nef from an aggressive strain of simian immunodeficiency virus. AB - The Nef from a highly virulent strain of simian immunodeficiency virus (SIV), SIVpbj14, and a Nef from the traditional strain SIVmac239 bearing the mutation from RQ to YE (YE-Nef) both induce an acute lethal disease in monkeys. The YE mutation and its surrounding sequence resemble the immunoreceptor tyrosine-based activation motif (ITAM), which is present in the cytoplasmic tail of T- and B cell antigen receptors and mediates signaling during lymphocyte activation. We show here that the ITAM from YE-Nef performs the same function. First, not only does YE-Nef increase the activity of the transcription factor NFAT, which is one of the downstream targets of T-cell activation, but the ITAM from the YE-Nef by itself also activates NFAT. Second, the ITAM from YE-Nef is phosphorylated on tyrosine residues by Lck and associates with ZAP-70, a T-cell-specific tyrosine kinase. The phosphorylation of both conserved tyrosine residues on the ITAM is required for the recruitment of ZAP-70. Finally, Lck is required for the activation of NFAT by YE-Nef. These results demonstrate that YE-Nef contains a functional ITAM and elucidate the molecular mechanisms underlying the pathogenesis of SIVpbj14. PMID- 9371618 TI - Protein 2A is not required for Theiler's virus replication. AB - Nonpolar mutations were introduced into all 12 regions of the genome of Theiler's murine encephalomyelitis virus. In agreement with data previously reported for other picornaviruses, mutations in regions 2B, 2C, 3A, 3B, 3C, and 3D totally abrogated viral RNA replication. Viruses with deletions in each of the capsid proteins retained RNA replication proficiency, although they were unable to propagate from cell to cell. As reported previously, mutations in the leader protein did not impair RNA replication or virus production in BHK-21 cells. Surprisingly, region 2A also appeared to be dispensable for the replication process. Indeed, up to 77 of the 133 amino acids of 2A could be deleted without significantly affecting RNA replication. 2A mutant viruses had only a slow cytopathic effect for BHK-21 cells and were totally avirulent for mice. As was the case for mutants lacking the leader protein, viruses with deletions in 2A propagated in BHK-21 cells, but their propagation was highly restricted in L929 cells. PMID- 9371617 TI - E1A 12S and 13S of the transformation-defective adenovirus type 12 strain CS-1 inactivate proteins of the RB family, permitting transactivation of the E2F dependent promoter. AB - The transformation-defective Vero cell host range mutant CS-1 of the highly oncogenic adenovirus type 12 (Ad12) (Ad12-CS-1) has a 69-bp deletion in the early region 1A (E1A) gene that removes the carboxy-terminal half of conserved region 2 and the amino-terminal half of the Ad12-specific so-called spacer that seems to play a pivotal role in the oncogenicity of the virus. Despite its deficiency in immortalizing and transforming primary rodent cells, we found that the E1A 13S protein of Ad12-CS-1 retains the ability to bind p105-RB, p107, and p130 in nuclear extract binding assays with glutathione S-transferase-E1A fusion proteins and Western blot analysis. Like wild-type E1A, the mutant protein was able to dissociate E2F from retinoblastoma-related protein-containing complexes, as judged from gel shift experiments with purified 12S and 13S proteins from transfection experiments with an E1A expression vector or from infection with the respective virus. Moreover, in transient expression assays, the 12S and 13S products of wild-type Ad12 and Ad12-CS-1 were shown to transactivate the Ad12 E1A promoter containing E2F-1 and E2F-5-motifs, respectively, in a comparable manner. The same results were obtained from transfection assays with the E2F motif dependent E2 promoter of adenovirus type 5 or the human dihydrofolate reductase promoter. These data suggest that efficient infection by Ad12 and the correlated virus-induced reprogramming of the infected cells, including the induction of cell cycle-relevant mechanisms (e.g. E2F activation), can be uncoupled from the transformation properties of the virus. PMID- 9371619 TI - Transient, nonlethal expression of genes in vertebrate cells by recombinant entomopoxviruses. AB - The group B entomopoxvirus (EPV) from Amsacta moorei (AmEPV) productively infects only insect cells. A series of AmEPV-lacZ recombinants was constructed in which the lacZ gene was regulated by either late (the AmEPV spheroidin or the cowpox virus A-type inclusion [ATI]) or early (the AmEPV esp [early strong promoter; derived from a 42-kDa AmEPV protein] or the Melolontha melolontha EPV fusolin, fus) virus promoters. When the AmEPV recombinants were used to infect vertebrate cells, beta-galactosidase expression occurred (in >30% of the cells) when lacZ was regulated by either the fus or esp early promoters but not when lacZ was regulated by the late promoters (spheroidin or ATI). Therefore, AmEPV enters vertebrate cells and undergoes at least a partial uncoating and early, but not late, viral genes are expressed. Neither viral DNA synthesis nor cytopathic effects were observed under any infection conditions. When an AmEPV recombinant virus containing the Aequorea victoria green fluorescent protein gene (gfp) under the control of the esp promoter was used to infect vertebrate cells at a low multiplicity of infection, single fluorescent cells resulted, which continued to divide over a period of several days, ultimately forming fluorescent cell clusters, suggesting that vertebrate cells survive the infection and continue to grow. Therefore, AmEPV may prove to be a highly efficient, nontoxic method of gene delivery into vertebrate cells for transient gene expression. PMID- 9371620 TI - Naked DNA vaccines expressing the prM and E genes of Russian spring summer encephalitis virus and Central European encephalitis virus protect mice from homologous and heterologous challenge. AB - Naked DNA vaccines expressing the prM and E genes of two tick-borne flaviviruses, Russian spring summer encephalitis (RSSE) virus and Central European encephalitis (CEE) virus were evaluated in mice. The vaccines were administered by particle bombardment of DNA-coated gold beads by Accell gene gun inoculation. Two immunizations of 0.5 to 1 microg of RSSE or CEE constructs/dose, delivered at 4 week intervals, elicited cross-reactive antibodies detectable by enzyme-linked immunosorbent assay and high-titer neutralizing antibodies to CEE virus. Cross challenge experiments demonstrated that either vaccine induced protective immunity to homologous or heterologous RSSE or CEE virus challenge. The absence of antibody titer increases after challenge and the presence of antibodies to E and prM, but not NS1, both before and after challenge suggest that the vaccines prevented productive replication of the challenge virus. One vaccination with 0.5 microg of CEE virus DNA provided protective immunity for at least 2 months, and two vaccinations protected mice from challenge with CEE virus for at least 6 months. PMID- 9371621 TI - Poliovirus-encoded 2C polypeptide specifically binds to the 3'-terminal sequences of viral negative-strand RNA. AB - The poliovirus-encoded, membrane-associated polypeptide 2C is believed to be required for initiation and elongation of RNA synthesis. We have expressed and purified recombinant, histidine-tagged 2C and examined its ability to bind to the first 100 nucleotides of the poliovirus 5' untranslated region of the positive strand and its complementary 3'-terminal negative-strand RNA sequences. Results presented here demonstrate that the 2C polypeptide specifically binds to the 3' terminal sequences of poliovirus negative-strand RNA. Since this region is believed to form a stable cloverleaf structure, a number of mutations were constructed to examine which nucleotides and/or structures within the cloverleaf are essential for 2C binding. Binding of 2C to the 3'-terminal cloverleaf of the negative-strand RNA is greatly affected when the conserved sequence, UGUUUU, in stem a of the cloverleaf is altered. Mutational studies suggest that interaction of 2C with the 3'-terminal cloverleaf of negative-strand RNA is facilitated when the sequence UGUUUU is present in the context of a double-stranded structure. The implication of 2C binding to negative-strand RNA in viral replication is discussed. PMID- 9371623 TI - Inhibition of Sendai virus genome replication due to promoter-increased selectivity: a possible role for the accessory C proteins. AB - The role of the negative-stranded virus accessory C proteins is difficult to assess because they appear sometimes as nonessential and thereby of no function. On the other hand, when a function is found, as in the case of Sendai virus, it represents an enigma, in that the C proteins inhibit replication under conditions where the infection follows an exponential course. Furthermore, this inhibitory function is exerted differentially: in contrast to the replication of internal deletion defective interfering (DI) RNAs, that of copy-back DI RNAs appears to escape inhibition, under certain experimental conditions (in vivo assay). In a reexamination of the C effect by the reverse genetics approach, it was found that copy-back RNA replication is inhibited by C in vivo as well, under conditions where the ratio of C to copy-back template is increased. This effect can be reversed by an increase in P but not L protein. The "rule of six" was differentially observed in the presence or absence of C. Finally, a difference in the ability of the replicating complex to tolerate promoter modifications in RNA synthesis initiation was shown to occur in the presence or the absence of C as well. We propose that C acts by increasing the selectivity of the replicating complex for the promoter cis-acting elements governing its activity. The inhibitory effect of C becomes the price to pay for this increased selectivity. PMID- 9371622 TI - Identification of two independent transcriptional activation domains in the Autographa californica multicapsid nuclear polyhedrosis virus IE1 protein. AB - The Autographa californica multicapsid nuclear polyhedrosis virus immediate-early protein, IE1, is a 582-amino-acid phosphoprotein that regulates the transcription of early viral genes. Deletion of N-terminal regions of IE1 in previous studies (G. R. Kovacs, J. Choi, L. A. Guarino, and M. D. Summers, J. Virol. 66:7429-7437, 1992) resulted in the loss of transcriptional activation, suggesting that this region may contain an acidic activation domain. To identify independently functional transcriptional activation domains, we developed a heterologous system in which potential regulatory domains were fused with a modified Escherichia coli Lac repressor protein that contains a nuclear localization signal (NLacR). Transcriptional activation by the resulting NLacR-IE1 chimeras was measured with a basal baculovirus early promoter containing optimized Lac repressor binding sites (lac operators). Chimeras containing IE1 peptides dramatically activated transcription of the basal promoter only when lac operator sequences were present. In addition, transcriptional activation by NLacR-IE1 chimeras was allosterically regulated by the lactose analog, isopropyl-beta-D thiogalactopyranoside (IPTG). For a more detailed analysis of IE1 regulatory domains, the M1 to T266 N-terminal portion of IE1 was subdivided (on the basis of average amino acid charge) into five smaller regions which were fused in various combinations to NLacR. Regions M1 to N125 and A168 to G222 were identified as independent transcriptional activation domains. Some NLacR-IE1 chimeras exhibited retarded migration in sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels. As with wild-type IE1, this aberrant gel mobility was associated with phosphorylation. Mapping studies with the NLacR-IE1 chimeras indicate that the M1 to A168 region of IE1 is necessary for this phosphorylation-associated effect. PMID- 9371624 TI - Activation of the adenovirus major late promoter by transcription factors MAZ and Sp1. AB - Multiple binding sites for the transcription factors MAZ and Sp1 within the adenovirus type 5 major late promoter have been identified by DNase I protection studies. In the proximal region of the promoter, both MAZ and Sp1 interact with GC-rich sequences flanking the TATA box. Two MAZ binding sites are centered at 18 and -36 relative to the transcriptional initiation site. Sp1 bound only to the -18 GC-rich sequence. Several sites of interaction were also evident in the distal region of the promoter. Both MAZ and Sp1 interacted with a sequence centered at -166, and MAZ bound weakly to an additional site centered at -130. Overexpression of MAZ or Sp1 activated expression from the major late promoter in transient expression assays. Mutational analysis of the GC-rich sequences in the major late promoter suggested that a primary target of MAZ activation is the GC rich sequences flanking the TATA sequence, whereas Sp1 requires the distal GC rich sequence elements to stimulate gene expression. This activation is enhanced by the adenovirus E1A protein, and evidence for interaction between E1A and both transcription factors was obtained by using an immunoprecipitation assay. Activation by MAZ and Sp1 also was observed in transfection studies using the complete adenovirus type 5 genome as the target. Increased levels of late mRNA from both the L1 and L5 regions were observed when MAZ or Sp1 expression plasmids were transfected with viral DNA. Unexpectedly, activation of the major late promoter by MAZ and Sp1 was detected irrespective of whether the viral DNA could replicate. PMID- 9371625 TI - trans-Complementation of yellow fever virus NS1 reveals a role in early RNA replication. AB - Mutational analysis of the nonstructural protein 1 (NS1) of yellow fever virus (YF) has implicated it in viral RNA replication. To further explore this observation, we sought a method for uncoupling NS1 function from NS1 expression and processing as part of the large YF polyprotein. Here we describe a strategy for providing NS1 in trans, utilizing a noncytopathic Sindbis virus vector. Replication of a defective YF genome containing a large in-frame deletion of NS1 was dependent on functional expression of NS1. Recovered mutant virus was shown to contain the deletion and was neutralized by YF-specific antiserum. Complemented mutant virus increased in titer with kinetics similar to those of parental YF 17D but peaked at lower titers. trans-complementation has allowed us to derive high-titer, helper-free stocks of YF defective in NS1 with which to further characterize the role of this gene product in RNA replication. The first cycles of RNA replication were analyzed by using a sensitive strand-specific RNase protection assay. We document these events for mutant and wild-type viruses in the presence or absence of complementation. These data strongly suggest a role for NS1 prior to or at initial minus-strand synthesis. PMID- 9371626 TI - Rotavirus RNA polymerase requires the core shell protein to synthesize the double stranded RNA genome. AB - Rotavirus cores contain the double-stranded RNA (dsRNA) genome, RNA polymerase VP1, and guanylyltransferase VP3 and are enclosed within a lattice formed by the RNA-binding protein VP2. Analysis of baculovirus-expressed core-like particles (CLPs) has shown that VP1 and VP2 assemble into the simplest core-like structures with replicase activity and that VP1, but not VP3, is essential for replicase activity. To further define the role of VP1 and VP2 in the synthesis of dsRNA from viral mRNA, recombinant baculoviruses containing gene 1 (rBVg1) and gene 2 (rBVg2) of SA11 rotavirus were generated and used to express recombinant VP1 (rVP1) and rVP2, respectively. After purification, the proteins were assayed individually and together for the ability to catalyze the synthesis of dsRNA in a cell-free replication system. The results showed that dsRNA was synthesized only in assays containing rVP1 and rVP2, thus establishing that both proteins are essential for replicase activity. Even in assays containing a primer-linked mRNA template, neither rVP1 nor rVP2 alone directed RNA synthesis. Characterization of the cis-acting replication signals in mRNA recognized by the replicase of rVP1 and rVP2 showed that they were the same as those recognized by the replicase of virion-derived cores, thus excluding a role for VP3 in recognition of the mRNA template by the replicase. Analysis of RNA-protein interactions indicated that the mRNA template binds strongly to VP2 in replicase assays but that the majority of the dsRNA product neither is packaged nor stably associates with VP2. The results of replicase assays performed with mutant VP2 containing a deletion in its RNA-binding domain suggests that the essential role for VP2 in replication is linked to the protein's ability to bind the mRNA template for minus-strand synthesis. PMID- 9371627 TI - Novel and dynamic evolution of equine infectious anemia virus genomic quasispecies associated with sequential disease cycles in an experimentally infected pony. AB - We have investigated the genetic evolution of three functionally distinct regions of the equine infectious anemia virus (EIAV) genome (env, rev, and long terminal repeat) during recurring febrile episodes in a pony experimentally infected with a well-characterized reference biological clone designated EIAV(PV). Viral populations present in the plasma of an EIAV(PV)-infected pony during sequential febrile episodes (18, 34, 80, 106, and 337 days postinfection) were amplified from viral RNA, analyzed, and compared to the inoculated strain. The comparison of the viral quasispecies showed that the inoculated EIAV(PV) quasispecies were all represented during the first febrile episode, but entirely replaced at the time of the second febrile episode, and that new predominant quasispecies were associated with each subsequent cycle of disease. One of the more surprising results was the in vivo generation of large deletion (up to 15 amino acids) in the principal neutralizing domain (PND) of gp90 during the third febrile episode. This deletion did not alter the competence for in vitro replication as shown by the analysis of a env chimeric clone with a partially deleted PND and did not altered the fitness of the virus in vivo, since this partially deleted envelope became the major population during the fourth febrile episode. Finally, we showed that the amino acid mutations were not randomly distributed but delineated eight variables regions, V1 to V8, with V3 containing the PND region. These studies provide the first detailed description of the evolution of EIAV genomic quasispecies during persistent infection and reveal new insights into the genetics and potential mechanisms of lentivirus genomic variation. PMID- 9371628 TI - Enhancement of feline immunodeficiency virus (FIV) infection after DNA vaccination with the FIV envelope. AB - Despite intensive experimentation to develop effective and safe vaccines against the human immunodeficiency viruses and other pathogenic lentiviruses, it remains unclear whether an immune response that does not afford protection may, on the contrary, produce adverse effects. In the present study, the effect of genetic immunization with the env gene was examined in a natural animal model of lentivirus pathogenesis, infection of cats by the feline immunodeficiency virus (FIV). Three groups of seven cats were immunized by intramuscular transfer of plasmid DNAs expressing either the wild-type envelope or two envelopes bearing mutations in the principal immunodominant domain of the transmembrane glycoprotein. Upon homologous challenge, determination of plasma virus load showed that the acute phase of viral infection occurred earlier in the three groups of cats immunized with FIV envelopes than in the control cats. Genetic immunization, however, elicited low or undetectable levels of antibodies directed against envelope glycoproteins. These results suggest that immunization with the FIV env gene may result in enhancement of infection and that mechanisms unrelated to enhancing antibodies underlay the observed acceleration. PMID- 9371629 TI - Direct demonstration of retroviral recombination in a rhesus monkey. AB - Recombination may be an important mechanism for increasing variation in retroviral populations. Retroviral recombination has been demonstrated in tissue culture systems by artificially creating doubly infected cells. Evidence for retroviral recombination in vivo is indirect and is based principally on the identification of apparently mosaic human immunodeficiency virus type 1 genomes from phylogenetic analyses of viral sequences. We infected a rhesus monkey with two different molecularly cloned strains of simian immunodeficiency virus. One strain of virus had a deletion in vpx and vpr, and the other strain had a deletion in nef. Each strain on its own induced low virus loads and was nonpathogenic in rhesus monkeys. When injected simultaneously into separate legs of the same monkey, persistent high virus loads and declines in CD4+ lymphocyte concentrations were observed. Analysis of proviral DNA isolated directly from peripheral blood mononuclear cells showed that full-length, nondeleted SIVmac239 predominated by 2 weeks after infection. These results provide direct experimental evidence for genetic recombination between two different retroviral strains in an infected host. The results illustrate the ease and rapidity with which recombination can occur in an infected animal and the selection that can occur for variants generated by genetic recombination. PMID- 9371630 TI - Oligomerization-dependent folding of the membrane fusion protein of Semliki Forest virus. AB - The spikes of alphaviruses are composed of three copies of an E2-E1 heterodimer. The E1 protein possesses membrane fusion activity, and the E2 protein, or its precursor form, p62 (sometimes called PE2), controls this function. Both proteins are, together with the viral capsid protein, translated from a common C-p62-E1 coding unit. In an earlier study, we showed that the p62 protein of Semliki Forest virus (SFV) dimerizes rapidly and efficiently in the endoplasmic reticulum (ER) with the E1 protein originating from the same translation product (so-called heterodimerization in cis) (B.-U. Barth, J. M. Wahlberg, and H. Garoff, J. Cell Biol. 128:283-291, 1995). In the present work, we analyzed the ER translocation and folding efficiencies of the p62 and E1 proteins of SFV expressed from separate coding units versus a common one. We found that the separately expressed p62 protein translocated and folded almost as efficiently as when it was expressed from a common coding unit, whereas the independently expressed E1 protein was inefficient in both processes. In particular, we found that the majority of the translocated E1 chains were engaged in disulfide-linked aggregates. This result suggests that the E1 protein needs to form a complex with p62 to avoid aggregation. Further analyses of the E1 aggregation showed that it occurred very rapidly after E1 synthesis and could not be avoided significantly by the coexpression of an excess of p62 from a separate coding unit. These latter results suggest that the p62-E1 heterodimerization has to occur very soon after E1 synthesis and that this is possible only in a cis-directed reaction which follows the synthesis of p62 and E1 from a common coding unit. We propose that the p62 protein, whose synthesis precedes that of the E1 protein, remains in the translocon of the ER and awaits the completion of E1. This strategy enables the p62 protein to complex with the E1 protein immediately after the latter has been made and thereby to control (suppress) its fusion activity. PMID- 9371631 TI - Promonocytic U937 subclones expressing CD4 and CXCR4 are resistant to infection with and cell-to-cell fusion by T-cell-tropic human immunodeficiency virus type 1. AB - Different strains of human immunodeficiency virus type 1 (HIV-1) vary markedly in the ability to infect cells of the monocyte/macrophage (M/M) lineage. M/M are generally resistant to infection with T-cell-tropic (T-tropic) strains of HIV-1. Recently, the chemokine receptors CCR5 and CXCR4 were identified as cofactors for fusion/entry of macrophage- and T-tropic strains of HIV-1, respectively. To investigate the mechanisms of resistance of M/M to T-tropic HIV-1 infection, we examined a number of subclones of the U937 promonocytic cell line. We found that certain subclones of U937 (plus clones) could, while others (minus clones) could not, support replication of T-tropic strains of HIV-1. We demonstrate that (i) both minus and plus clones support HIV-1 replication when transfected with an infectious molecular cDNA clone of a T-tropic HIV-1; (ii) minus clones do not, but plus clones do, efficiently support fusion with cells expressing HIV-1 IIIB Env; (iii) both plus and minus clones (with the exception of one clone) express physiologically functional CXCR4 protein as well as CD4 on the cell surface; (iv) introduction of CXCR4 into the CXCR4-negative clone does not restore fusogenicity with or susceptibility to T-tropic HIV-1; and (v) a ligand (stromal cell-derived factor 1) for or a monoclonal antibody (12G5) to CXCR4 does not effectively inhibit HIV-mediated cell-to-cell fusion of U937 cells. These data indicate that resistance to T-tropic HIV-1 infection of U937 minus clones occurs at fusion/ entry events and that expression of functional CXCR4 and CD4 is not a sole determinant for susceptibility to T-tropic HIV-1 infection; furthermore, they suggest that other factors are positively or negatively involved in HIV-mediated cell-to-cell fusion in U937 promonocytic cells. PMID- 9371632 TI - Vaccination against persistent viral infection exacerbates CD4+ T-cell-mediated immunopathological disease. AB - Lymphocytic choriomeningitis virus (LCMV) infection of normal mice results in a fatal immunopathologic meningitis mediated by CD8+ cytotoxic T lymphocytes (CTL). We have previously shown that female beta2-microglobulin-deficient (beta2m-/-) mice, which are also deficient in CD8+ T cells, are susceptible to LCMV-induced immune-mediated meningitis, characterized by significant weight loss and mortality. This LCMV disease in beta2m-/- mice is mediated by CD4+ T lymphocytes. Our previous studies have also demonstrated that male beta2m-/- mice are less susceptible than female beta2m-/- mice to LCMV-induced, immune-mediated mortality and weight loss. In this report, we show that vaccination of male beta2m-/- mice enhances immunopathology following intracranial infection with LCMV. We observed increased production of gamma interferon (IFN-gamma), an increase in CD4+ CTL precursor frequency, and an increased frequency of IFN-gamma-producing cells from spleen cells of vaccinated male beta2m-/- mice. Vaccinated male beta2m-/- mice also had significantly increased inflammation in the cerebrospinal fluid (CSF), characterized by a large CD4+ T-cell infiltrate. CSF cells from vaccinated mice showed increased production of IFN-gamma on day 7 postchallenge. Neither vaccinated nor control beta2m-/- mice were able to clear virus, and the two groups had similarly high levels of virus early after infection. These results suggest that the magnitude of the early immune response is more important than the level of virus in the brain in determining the outcome of immunopathology in beta2m-/- mice. We show here that vaccination can increase CD4+ T-cell-dependent immunopathology to a persistent viral infection. PMID- 9371633 TI - Nick sensing by vaccinia virus DNA ligase requires a 5' phosphate at the nick and occupancy of the adenylate binding site on the enzyme. AB - Vaccinia virus DNA ligase has an intrinsic nick-sensing function. The enzyme discriminates at the substrate binding step between a DNA containing a 5' phosphate and a DNA containing a 5' hydroxyl at the nick. Further insights into nick recognition and catalysis emerge from studies of the active-site mutant K231A, which is unable to form the covalent ligase-adenylate intermediate and hence cannot activate a nicked DNA substrate via formation of the DNA-adenylate intermediate. Nonetheless, K231A does catalyze phosphodiester bond formation at a preadenylated nick. Hence, the active-site lysine of DNA ligase is not required for the strand closure step of the ligation reaction. The K231A mutant binds tightly to nicked DNA-adenylate but has low affinity for a standard DNA nick. The wild-type vaccinia virus ligase, which is predominantly ligase-adenylate, binds tightly to a DNA nick. This result suggests that occupancy of the AMP binding pocket of DNA ligase is essential for stable binding to DNA. Sequestration of an extrahelical nucleotide by DNA-bound ligase is reminiscent of the base-flipping mechanism of target-site recognition and catalysis used by other DNA modification and repair enzymes. PMID- 9371634 TI - Late treatment with polyene antibiotics can prolong the survival time of scrapie infected animals. AB - Amphotericin B (AmB) is one of the few drugs able to prolong survival times in experimental scrapie and delays the accumulation of PrPres, a specific marker of this disease in the brain in vivo. Previous reports showed that the AmB effect is observed only if the drug is administered around the time of infection. In the present study, intracerebrally infected mice were treated with AmB or one of its derivatives, MS-8209, between 80 and 140 days postinoculation. We observed an increased incubation time and a delay in PrPres accumulation and glial fibrillary acidic protein gene expression. Treatment starting at 80 days postinoculation was as efficient as long-term treatment starting the day of inoculation. Our results indicate that polyene antibiotics may interfere, throughout the course of the experimental disease, with the propagation of the scrapie agent. PMID- 9371635 TI - Nuclear import and export of influenza virus nucleoprotein. AB - Influenza virus nucleoprotein (NP) shuttles between the nucleus and the cytoplasm. A nuclear localization signal (NLS) has been identified in NP at amino acids 327 to 345 (J. Davey et al., Cell 40:667-675, 1985). However, some NP mutants that lack this region still localize to the nucleus, suggesting an additional NLS in NP. We therefore investigated the nucleocytoplasmic transport of NP from influenza virus A/WSN/33 (H1N1). NP deletion constructs lacking the 38 N-terminal amino acids, as well as those lacking the 38 N-terminal amino acids and the previously identified NLS, localized to both the cytoplasm and the nucleus. Nuclear localization of a protein containing amino acids 1 to 38 of NP fused to LacZ proved that these 38 amino acids function as an NLS. Within this region, we identified two basic amino acids, Lys7 and Arg8, that are crucial for NP nuclear import. After being imported into the nucleus, the wild-type NP and the NP-LacZ fusion construct containing amino acids 1 to 38 of NP were both transported back to the cytoplasm, where they accumulated. These data indicate that NP has intrinsic structural features that allow nuclear import, nuclear export, and cytoplasmic accumulation in the absence of any other viral proteins. Further, the information required for nuclear import and export is located in the 38 N-terminal amino acids of NP, although other NP nuclear export signals may exist. Treatment of cells with a protein kinase C inhibitor increased the amounts of nuclear NP, whereas treatment of cells with a phosphorylation stimulator increased the amounts of cytoplasmic NP. These findings suggest a role of phosphorylation in nucleocytoplasmic transport of NP. PMID- 9371636 TI - Role of sialyloligosaccharide binding in Theiler's virus persistence. AB - Theiler's murine encephalomyelitis viruses (TMEVs) belong to the Picornaviridae family and are divided into two groups, typified by strain GDVII virus and members of the TO (Theiler's original) group. The highly virulent GDVII group causes acute encephalitis in mice, while the TO group is less virulent and causes a chronic demyelinating disease which is associated with viral persistence in mice. This persistent central nervous system infection with demyelination resembles multiple sclerosis (MS) in humans and has thus become an important model for studying MS. It has been shown that some of the determinants associated with viral persistence are located on the capsid proteins of the TO group. Structural comparisons of two persistent strains (BeAn and DA) and a highly virulent strain (GDVII) showed that the most significant structural variations between these two groups of viruses are located on the sites that may influence virus binding to cellular receptors. Most animal viruses attach to specific cellular receptors that, in part, determine host range and tissue tropism. In this study, atomic models of TMEV chimeras were built with the known structures of GDVII, BeAn, and DA viruses. Comparisons among the known GDVII, BeAn, and DA structures as well as the predicted models for the TMEV chimeras suggested that a gap on the capsid surface next to the putative receptor binding site, composed of residues from VP1 and VP2, may be important in determining viral persistence by influencing virus attachment to cellular receptors, such as sialyloligosaccharides. Our results showed that sialyllactose, the first three sugar molecules of common oligosaccharides on the surface of mammalian cells, inhibits virus binding to the host cell and infection with the persistent BeAn virus but not the nonpersistent GDVII and chimera 39 viruses. PMID- 9371637 TI - Efficient expression by an alphavirus replicon of a functional ribozyme targeted to human immunodeficiency virus type 1. AB - Intracellular applications of ribozymes have been limited partly by the availability of suitable high-expression systems. For RNA effectors, consideration of an RNA virus vector system for delivery and expression is reasonable. We show that alphavirus replicons can be highly efficient nonintegrating ribozyme-expressing vectors. Using a hammerhead ribozyme targeted to a highly conserved sequence in the U5 region of the human immunodeficiency virus type 1 (HIV-1) long terminal repeat, we demonstrate that a full-length 8.3 kb Semliki Forest virus ribozyme (SFVRz) chimeric RNA maintains catalytic activity. SFVRz is packaged into viral particles, and these particles transduce mammalian cells efficiently. SFVRz-transduced BHK cells were found to produce large amounts of genomic and subgenomic forms of ribozyme-containing RNAs that are functional in cleaving a U5-tagged mRNA. The RNase protection assay shows that HIV-1 U5-chloramphenicol acetyltransferase mRNA expressed intracellularly from an RNA polymerase II promoter is quantitatively eliminated in SFVRz transduced BHK cells. PMID- 9371639 TI - Human immunodeficiency virus type 1 Vpr interacts with HHR23A, a cellular protein implicated in nucleotide excision DNA repair. AB - The human immunodeficiency virus type 1 (HIV-1) vpr gene is an evolutionarily conserved gene among the primate lentiviruses HIV-1, HIV-2, and simian immunodeficiency viruses. One of the unique functions attributed to the vpr gene product is the arrest of cells in the G2 phase of the cell cycle. Here we demonstrate that Vpr interacts physically with HHR23A, one member of an evolutionarily conserved gene family involved in nucleotide excision repair. Interaction of Vpr with HHR23A was initially identified through a yeast two hybrid screen and was confirmed by the demonstration of direct binding between bacterially expressed recombinant and transiently expressed or chemically synthesized protein products. Visualization of HHR23A and Vpr by indirect immunofluorescence and confocal microscopy indicates that the two proteins colocalize at or about the nuclear membrane. We also map the Vpr-binding domain in HHR23A to a C-terminal 45-amino-acid region of the protein previously shown to have homology to members of the ubiquitination pathway. Overexpression of HHR23A and a truncated derivative which includes the Vpr-binding domain results in a partial alleviation of the G2 arrest induced by Vpr, suggesting that the interaction between Vpr and HHR23A is critical for cell cycle arrest induced by Vpr. These results provide further support for the hypothesis that Vpr interferes with the normal function of a protein or proteins involved in the DNA repair process and, thus, in the transmission of signals that allow cells to transit from the G2 to the M phase of the cell cycle. PMID- 9371640 TI - Dissecting the roles of VP0 cleavage and RNA packaging in picornavirus capsid stabilization: the structure of empty capsids of foot-and-mouth disease virus. AB - Empty capsids of foot-and-mouth disease virus (FMDV) type A22 Iraq 24/64, whose structure has been solved by X-ray crystallography, are unusual for picornaviruses since they contain VP2 and VP4, the cleavage products of the protein precursor VP0. Both the N terminus of VP1 and the C terminus of VP4, which pack together close to the icosahedral threefold symmetry axis where three pentamers associate, are more disordered in the empty capsid than they are in the RNA-containing virus. The ordering of these termini in the presence of RNA strengthens interactions within a single protomer and between protomers belonging to different pentamers. The disorder in the FMDV empty capsid forms a subset of that seen in the poliovirus empty capsid, which has VP0 intact. Thus, VP0 cleavage confers stability on the picornavirus capsid over and above that attributable to RNA encapsidation. In both FMDV and poliovirus empty capsids, the internal disordering uncovers a conserved histidine which has been proposed to be involved in the cleavage of VP0. A comparison of the putative active sites in FMDV and poliovirus suggests a structural explanation for the sequence specificity of the cleavage reaction. PMID- 9371638 TI - Analysis of the interaction of the human immunodeficiency virus type 1 gp120 envelope glycoprotein with the gp41 transmembrane glycoprotein. AB - The human immunodeficiency virus type 1 (HIV-1) gp120 exterior envelope glycoprotein interacts with the viral receptor (CD4) and with the gp41 transmembrane envelope glycoprotein. To study the interaction of the gp120 and gp41 envelope glycoproteins, we compared the abilities of anti-gp120 monoclonal antibodies to bind soluble gp120 and a soluble glycoprotein, sgp140, that contains gp120 and gp41 exterior domains. The occlusion or alteration of a subset of gp120 epitopes on the latter molecule allowed the definition of a gp41 "footprint" on the gp120 antibody competition map. The occlusion of these epitopes on the sgp140 glycoprotein was decreased by the binding of soluble CD4. The gp120 epitopes implicated in the interaction with the gp41 ectodomain were disrupted by deletions of the first (C1) and fifth (C5) conserved gp120 regions. These deletions did not affect the integrity of the discontinuous binding sites for CD4 and neutralizing monoclonal antibodies. Thus, the gp41 interface on the HIV-1 gp120 glycoprotein, which elicits nonneutralizing antibodies, can be removed while retaining immunologically desirable gp120 structures. PMID- 9371641 TI - A major human immunodeficiency virus type 1-initiated killing pathway distinct from apoptosis. AB - We have investigated the relative contribution of apoptosis or programmed cell death (PCD) to cell killing during acute infection with T-cell-tropic, cytopathic human immunodeficiency virus type 1 (HIV-1), by employing diverse strategies to inhibit PCD or to detect its common end-stage sequelae. When Bcl-2-transfected cell lines were infected with HIV-1, their viability was only slightly higher than that of control infections. Although the adenovirus E1B 19-kDa protein has been reported to be a stronger competitor of apoptosis than Bcl-2, it did not inhibit HIV-mediated cell death better than Bcl-2 protein. Competition for Fas ligand or inactivation of the Fas pathway secondary to intracellular mutation (MOLT-4 T cells) also had modest effects on overall cell death during acute HIV infection. In contrast to these observations with HIV infection or with HIV envelope-initiated cell death, Tat-expressing cell lines were much more susceptible (200% enhancement) to Fas-induced apoptosis than controls and Bcl-2 overexpression strongly (75%) inhibited this apoptotic T-cell death. PCD associated with FasR ligation resulted in the cleavage of common interleukin 1beta-converting enzyme (ICE)-protease targets, poly(ADP-ribose) polymerase (PARP) and pro-ICE, whereas cleaved products were not readily detected during HIV infection of peripheral blood mononuclear cells or T-cell lines even during periods of extensive cell death. These results indicate that one important form of HIV-mediated cell killing proceeds by a pathway that lacks the characteristics of T-cell apoptosis. Our observations support the conclusion that at least two HIV genes (env and tat) can kill T cells by distinct pathways and that an envelope-initiated process of T-cell death can be discriminated from apoptosis by many of the properties most closely associated with apoptotic cell death. PMID- 9371642 TI - A herpesvirus of rhesus monkeys related to the human Kaposi's sarcoma-associated herpesvirus. AB - A herpesvirus that is related to but distinct from the Kaposi's sarcoma associated herpesvirus (KSHV, or human herpesvirus 8) was isolated from rhesus monkeys. The sequence of 10.6 kbp from virion DNA revealed the presence of an interleukin-6 homolog similar to what is present in KSHV and a closer relatedness of the DNA polymerase and glycoprotein B reading frames to those of KSHV than to those of any other herpesvirus. This rhesus monkey herpesvirus replicated lytically and to high titers in cultured rhesus monkey fibroblasts. Antibody testing revealed a high prevalence for at least 10 years in our rhesus monkey colony and a high prevalence in two other colonies that were tested. Thus, rhesus monkeys naturally harbor a virus related to KSHV, which we have called RRV, for rhesus monkey rhadinovirus. PMID- 9371643 TI - Allele-specific adaptation of poliovirus VP1 B-C loop variants to mutant cell receptors. AB - Previous work has shown that three different mutations in domain 1 of the poliovirus receptor (Pvr), two in the predicted C'-C" ridge and one in the D-E loop, abolish binding of the P1/Mahoney strain. All three receptor defects could be suppressed by a mutation in the VP1 B-C loop of the viral capsid that was present in all 16 P1/Mahoney isolates adapted to the mutant receptors. To identify allele-specific mutations that enable poliovirus to utilize mutant receptors, and to understand the role of the VP1 B-C loop in adaptation, we selected mutant receptor-adapted viruses derived from two P1/Mahoney variants, one which lacks the VP1 B-C loop and one in which the VP1 B-C loop is replaced with the corresponding sequence from the P2/Lansing strain. Six adapted viral isolates were obtained after passage on mutant receptor-expressing cell lines. Sequence analysis revealed that each virus contained three to five mutations, and a total of 18 amino acid changes at 17 capsid residues were identified. Site directed mutagenesis was used to evaluate the role of these mutations in adaptation to mutant Pvr. The results demonstrate that mutations in the viral canyon floor and rim are allele specific and compensate only for receptor defects in the C'-C" ridge of Pvr, suggesting that these sites interact in the virus receptor complex. Furthermore, mutations in the VP1 E-F loop suppressed Pvr D-E loop defects, implying that the Pvr D-E loop contacts the VP1 E-F loop. Most of the other mutations mapped to interior capsid residues, some interacting with the fivefold- or threefold-related protomers. These mutations may regulate receptor interaction by controlling the structural flexibility of the viral capsid. In viruses lacking the VP1 B-C loop, single mutations were not sufficient to confer the adapted phenotype, in contrast to the 414 virus, which contains the B-C loop. Although the VP1 B-C loop appeared to be dispensable for adaptation, it may have provided a selective advantage in adaptation of P1/Mahoney to mutant Pvr. PMID- 9371645 TI - Gain or loss of diabetogenicity resulting from a single point mutation in recombinant encephalomyocarditis virus. AB - Molecular pathogenic mechanisms for virus-induced disease have received considerable attention. Encephalomyocarditis (EMC) virus-induced diabetes in mice has been extensively studied to elucidate the cellular and molecular mechanisms involved in the development of this disease. In this study, we report for the first time that a single point mutation at nucleotide position 3155 or 3156 of the recombinant EMC viral genome, located on the major capsid protein VP1, which causes an amino acid change, results in the gain or loss of viral diabetogenicity. A G base at nucleotide position 3155 (alanine at amino acid position 776 of the EMC virus polyprotein [Ala776]; GCC) results in viral diabetogenicity, whereas the substitution of other bases at the same or next position results in a loss of viral diabetogenicity. This finding provides clear evidence that a point mutation at a critical site in a viral genome affects the ability of the virus to cause a cell-specific disease. PMID- 9371644 TI - Overexpression of A-myb induces basic fibroblast growth factor-dependent proliferation of chicken neuroretina cells. AB - A-Myb behaves similarly to c-Myb in chicken neuroretina cells in its ability to induce fibroblast-like differentiation, to promote growth in the presence of basic fibroblast growth factor (bFGF), and to induce Pax-6 and mim-1 expression. The one difference between c-Myb and A-Myb in these cells is that the former but not the latter protein causes colony formation in soft agar in the presence of bFGF. PMID- 9371646 TI - The feline leukemia virus long terminal repeat contains a potent genetic determinant of T-cell lymphomagenicity. AB - Feline leukemia virus (FeLV) is an important pathogen of domestic cats. The most common type of malignancy associated with FeLV is T-cell lymphoma. SL3-3 (SL3) is a potent T-cell lymphomagenic murine leukemia virus. Transcriptional enhancer sequences within the long terminal repeats (LTRs) of SL3 and other murine retroviruses are crucial genetic determinants of the pathogenicities of these viruses. The LTR enhancer sequences of FeLV contain identical binding sites for some of the transcription factors that are known to affect the lymphomagenicity of SL3. To test whether the FeLV LTR contains a genetic determinant of lymphomagenicity, a recombinant virus that contained the U3 region of a naturally occurring FeLV isolate, LC-FeLV, linked to the remainder of the genome of SL3 was generated. When inoculated into mice, the recombinant virus induced T-cell lymphomas nearly as quickly as SL3. Moreover, the U3 sequences of LC-FeLV were found to have about half as much transcriptional activity in T lymphocytes as the corresponding sequences of SL3. This level of activity was severalfold higher than that of the LTR of weakly leukemogenic Akv virus. Thus, the FeLV LTR contains a potent genetic determinant of T-cell lymphomagenicity. Presumably, it is adapted to be recognized by transcription factors present in T cells of cats, and this yields a relatively high level of transcription that allows the enhancer to drive the requisite steps in the process of lymphomagenesis. PMID- 9371647 TI - Antiviral determinants of rat Mx GTPases map to the carboxy-terminal half. AB - Rat Mx2 and rat Mx3 are two alpha/beta interferon-inducible cytoplasmic GTPases that differ in three residues in the amino-terminal third, which also contains the tripartite GTP-binding domain, and that differ in five residues in the carboxy-terminal quarter, which also contains a dimerization domain. While Mx2 is active against vesicular stomatitis virus (VSV), Mx3 lacks antiviral activity. We mapped the functional difference between Mx2 and Mx3 protein to two critical residues in the carboxy-terminal parts of the molecules. An exchange of either residue 588 or 630 of Mx2 with the corresponding residues of Mx3 abolished anti VSV activity, and the introduction of the two Mx2 residues on an Mx3 background partially restored anti-VSV activity. These results are consistent with the facts that Mx2 and Mx3 have similar intrinsic GTPase activities and that the GTPase domain of Mx3 can fully substitute for the GTPase domain of Mx2. Nevertheless, the amino-terminal third containing the GTP-binding domain is necessary for antiviral activity, since an amino-terminally truncated Mx2 protein is devoid of anti-VSV activity. Furthermore, Fab fragments of a monoclonal antibody known to neutralize antiviral activity block GTPase activity by binding an epitope in the carboxy-terminal half of Mx2 or Mx3 protein. The results are consistent with a two-domain model in which both the conserved amino-terminal half and the less well-conserved carboxy-terminal half of Mx proteins carry functionally important domains. PMID- 9371648 TI - An SL3-3 murine leukemia virus enhancer variant more pathogenic than the wild type obtained by assisted molecular evolution in vivo. AB - SL3-3 is a highly T-lymphomagenic murine retrovirus in which the transcriptional enhancer is a major oncogenic determinant. Here, we describe an SL3-3 enhancer variant that induced T-cell lymphomas in all inoculated mice with a shorter latency period than wild-type SL3-3. The enhancer repeat region of this variant contains two deletions encompassing the nuclear factor 1 binding sites in addition to an additional intact enhancer repeat element. Tumors induced by this variant were T-cell lymphomas, as indicated by T-cell receptor rearrangements, and contained the input provirus enhancer regions. The variant was the result of mutation of specific transcription factor binding sites in the viral enhancer, isolation of rare second-site enhancer variants from the resulting induced tumors, and subsequent restoration of the original first-site mutations of one such variant. We have termed this process assisted molecular evolution. PMID- 9371649 TI - Involvement of a subgenomic mRNA in the generation of a variable population of defective citrus tristeza virus molecules. AB - The fusion sites between the termini of naturally occurring defective RNAs (D RNAs) from three citrus tristeza virus (CTV) isolates were sequenced. Seven of eight clones showed a common 3' terminus of 940 nucleotides (nt) fused to 5' termini with different sizes. An extra cytosine nucleotide was found at the junction site of the majority of the common 3' D-RNAs. Molecular analysis of the plus and minus strands of the 0.9-kbp double-stranded RNA, corresponding to the CTV open reading frame 11 subgenomic RNA (sgRNA), showed that they were identical in length and sequence to the common 3' sequence of the D-RNAs. These results imply that viral sgRNA messengers also function as building components for genomic rearrangement and exchange of complete viral genes. PMID- 9371650 TI - Direct interaction between human cytomegalovirus glycoprotein B and cellular annexin II. AB - Cellular annexin II has been shown to specifically bind human cytomegalovirus (HCMV) and be a component of highly purified virions. In this report, we characterize the interaction of annexin II with HCMV. We found that the binding of annexin II to the HCMV envelope occurs partially through the calcium-dependent phospholipid-binding ability of annexin II since some annexin II was dissociated from virions with chelating agents. However, a substantial proportion of virion associated annexin II was resistant to chelation, which suggested a calcium independent interaction between annexin II and an HCMV envelope component. The search for a nonphospholipid component to account for this binding led to the discovery that HCMV glycoprotein B (gpUL55) (gB) can physically interact with annexin II. We present three lines of evidence to support the conclusion that HCMV gB can bind host cell annexin II. PMID- 9371651 TI - Replication and neutralization of human immunodeficiency virus type 1 lacking the V1 and V2 variable loops of the gp120 envelope glycoprotein. AB - A human immunodeficiency virus type 1 (HIV-1) mutant lacking the V1 and V2 variable loops in the gp120 exterior envelope glycoprotein replicated in Jurkat lymphocytes with only modest delays compared with the wild-type virus. Revertants that replicated with wild-type efficiency rapidly emerged and contained only a few amino acid changes in the envelope glycoproteins compared with the parent virus. Both the parent and revertant viruses exhibited increased sensitivity to neutralization by antibodies directed against the V3 loop or a CD4-induced epitope on gp120 but not by soluble CD4 or an antibody against the CD4 binding site. This result demonstrates the role of the gp120 V1 and V2 loops in protecting HIV-1 from some subsets of neutralizing antibodies. PMID- 9371652 TI - Efficient neutralization of foot-and-mouth disease virus by monovalent antibody binding. AB - Neutralization of an aphthovirus by monovalent binding of an antibody is reported. Foot-and-mouth disease virus (FMDV) clone C-S8c1 was neutralized by monoclonal antibody (MAb) SD6, which was directed to a continuous epitope within a major antigenic site of the G-H loop of capsid protein VP1. On a molar basis, the Fab fragment was at most fivefold less active in neutralization than the intact antibody, and both blocked virus attachment to cells. Neither the antibody nor the Fab fragment caused aggregation of virions, as evidenced by sucrose gradient sedimentation studies of the antibody-virus complex formed at antibody to virion ratios of 1:50 to 1:10,000. The results of neutralization of infectivity and of ultracentrifugation are fully consistent with structural data based on X-ray crystallographic and cryoelectron microscopy studies, which showed monovalent interaction of the antibody with a critical receptor binding motif Arg Gly-Asp. The conclusions of these neutralization studies are that (i) bivalent binding of antibody is not a requisite for strong neutralization of aphthoviruses and (ii) aggregation of viral particles, which has been proposed to be the dominant neutralization mechanism of antibodies that bind monovalently to virions, is not necessary for the neutralization of FMDV C-S8c1 by MAb SD6. PMID- 9371653 TI - Reduced viral load and lack of CD4 depletion in SCID-hu mice infected with Rev independent clones of human immunodeficiency virus type 1. AB - The posttranscriptional control element CTE of the simian type D retrovirus has been shown to support replication of Rev-Rev-responsive-element (RRE)-deficient molecular clones of human immunodeficiency virus type 1 (HIV-1). Upon infection of peripheral blood mononuclear cells in vitro, these CTE-containing Rev independent viruses that are nef+ or nef-minus showed lower replicative capacity and infectivity than the wild-type HIV-1. We studied the effects of Rev-RRE replacement by the CTE on HIV-1 expression with SCID-hu mice. The nef+ and nef minus Rev-independent viruses established infection with kinetics slower than that of the nef-minus NL4-3. Most importantly, no depletion of CD4-bearing thymocytes was observed after 6 weeks for mice infected with these Rev independent viruses. This is in contrast to the infection with both wild-type and nef-minus viruses, which led to varying depletion of thymocytes. These data suggest an attenuated phenotype for growth and cytotoxicity of the Rev independent HIV-1 clones in SCID-hu mice, independent of the presence of Nef. The mutant viruses, which have the essential Rev-RRE regulatory system eliminated, display a distinct phenotype not previously observed with HIV mutant viruses having deletions of accessory genes. Therefore, replacement of the Rev-RRE regulatory axis may generate viruses with altered biological properties in vivo. PMID- 9371654 TI - Structure and function of the long terminal repeats of feline leukemia viruses derived from naturally occurring acute myeloid leukemias in cats. AB - Long terminal repeats of feline leukemia viruses cloned from feline acute myeloid leukemias frequently contained direct repeats of 40 to 74 bp in the upstream region of the enhancer (URE). The repetitive URE conferred an enhancer function upon gene expression in myeloid cells, suggesting its association with tumorigenic potential in myeloid cells. PMID- 9371655 TI - Tyrosine phosphorylation of the herpes simplex virus type 1 regulatory protein ICP22 and a cellular protein which shares antigenic determinants with ICP22. AB - At least eight herpes simplex virus type 1 (HSV-1) and five HSV-2 proteins were tyrosine phosphorylated in infected cells. The first viral tyrosine phosphoprotein identified was the HSV-1 regulatory protein ICP22. Also, two novel phosphotyrosine proteins were bound by anti-ICP22 antibodies. H(R22) is a cellular protein, while the F(R10) protein is observed only in HSV-1-infected cells. PMID- 9371656 TI - The published DNA sequence of human cytomegalovirus strain AD169 lacks 929 base pairs affecting genes UL42 and UL43. AB - Compared with the published DNA sequence (M. S. Chee, et al. Curr. Top. Microbiol. Immunol. 154:125-170, 1990), most isolates of human cytomegalovirus strain AD169 contain an additional 929 bp after nucleotide 54612. This results in a changed reading frame for the 5'-terminal 50 codons of gene UL42 and expansion of gene UL43 (a US22 family member) from 187 (3'-truncated) to 423 (full-length) codons. The UL42 and UL43 gene products are nonessential for growth in culture. PMID- 9371657 TI - Structure-function analysis of the triphosphatase component of vaccinia virus mRNA capping enzyme. AB - The N-terminal 60 kDa (amino acids 1 to 545) of the D1 subunit of vaccinia virus mRNA capping enzyme is an autonomous bifunctional domain with triphosphatase and guanylyltransferase activities. We previously described two alanine cluster mutations, R77 to A (R77A)-K79A and E192A-E194A, which selectively inactivated the triphosphatase component. Here, we characterize the activities of 11 single alanine mutants-E37A, E39A, Q60A, E61A, T67A, T69A, K75A, R77A, K79A, E192A, and E194A-and a quadruple mutant in which four residues (R77, K79, E192, and E194) were replaced by alanine. We report that Glu-37, Glu-39, Arg-77, Glu-192, and Glu 194 are essential for gamma-phosphate cleavage. The five essential residues are conserved in the capping enzymes of Shope fibroma virus, molluscum contagiosum virus, and African swine fever virus. Probing the structure of D1(1-545) by limited V8 proteolysis suggested a bipartite subdomain structure. The essential residue Glu-192 is the principal site of V8 cleavage. Secondary cleavage by V8 occurs at the essential residue Glu-39. The triphosphatase-defective quadruple mutant transferred GMP to the triphosphate end of poly(A) to form a tetraphosphate cap structure, GppppA. We report that GppppA-capped RNA is a poor substrate for cap methylation by the vaccinia virus and Saccharomyces cerevisiae RNA (guanine-7) methyltransferases. The transcription termination factor activity of the D1-D12 capping enzyme heterodimer was not affected by mutations that abrogated ATPase activity. Thus, the capping enzyme is not responsible for the requirement for ATP hydrolysis during transcription termination. PMID- 9371658 TI - A decay-accelerating factor-binding strain of coxsackievirus B3 requires the coxsackievirus-adenovirus receptor protein to mediate lytic infection of rhabdomyosarcoma cells. AB - The composition of the cellular receptor complex for coxsackievirus B3 (CVB3) has been an area of much contention for the last 30 years. Recently, two individual components of a putative CVB3 cellular receptor complex have been identified as (i) decay-accelerating factor (DAF) and (ii) the coxsackievirus-adenovirus receptor protein (CAR). The present study elucidates the individual roles of DAF and CAR in cell entry of CVB3 Nancy. First, we confirm that the DAF-binding phenotype of CVB3 correlates to the presence of key amino acids located in the viral capsid protein, VP2. Second, using antibody blockade, we show that complete protection of permissive cells from infection by high input multiplicities of CVB3 requires a combination of both anti-DAF and anti-CAR antibodies. Finally, it is shown that expression of the CAR protein on the surface of nonpermissive DAF expressing RD cells renders them highly susceptible to CVB3-mediated lytic infection. Therefore, although the majority of CVB3 Nancy attaches to the cell via DAF, only virus directly interacting with the CAR protein mediates lytic infection. The role of DAF in CVB3 cell infection may be analogous to that recently described for coxsackievirus A21 (D. R. Shafren, D. J. Dorahy, R. A. Ingham, G. F. Burns, and R. D. Barry, J. Virol. 71:4736-4743, 1997), in that DAF may act as a CVB3 sequestration site, enhancing viral presentation to the functional CAR protein. PMID- 9371659 TI - Rescue of synthetic minireplicons establishes the absence of the NS1 and NS2 genes from avian pneumovirus. AB - We have determined the nucleotide sequences of the regions 3' and 5' proximal to the avian pneumovirus (APV) N and L genes, respectively. These sequences were used in the construction of a synthetic minireplicon construct in which the chloramphenicol acetyltransferase (CAT) reporter gene was flanked at its 3' end with the APV leader together with the APV N gene start signal and at its 5' end with the APV L gene end signal and the genome trailer region. The ability of T7 RNA polymerase runoff transcripts to direct the replication and expression of the CAT reporter gene in APV-infected cells demonstrated the ability of the putative leader and trailer regions to direct genome replication and gene expression. Furthermore, this confirms the absence of the NS1 and NS2 gene analogs within the APV genome. We were able to detect the expression of CAT protein from cells that had been infected with supernatants from the initially infected and transfected cells. These results have identified the cis-acting sequences of APV responsible for viral replication, gene expression, and packaging into virus-like particles. PMID- 9371661 TI - Gene targeting: techniques and applications to transplantation. PMID- 9371660 TI - Role of a single amino acid at the amino terminus of the simian virus 5 F2 subunit in syncytium formation. AB - The fusion (F) protein of simian virus 5 (strain W3A) induced extensive cell fusion in BHK cells when expressed alone, while that of strain WR did not. Mutational analysis demonstrated that the fusing activity can be transferred to the WR F protein by a proline residue at position 22 of subunit W3A F2. PMID- 9371663 TI - Fetal rat hepatocytes: isolation, characterization, and transplantation in the Nagase analbuminemic rats. AB - BACKGROUND: In contrast to adult hepatocytes, fetal hepatocytes (FH) are thought to be highly proliferative, less immunogenic, and resistant to cryopreservation and ischemic injury. These qualities could enhance FH engraftment, proliferation, and gene transfer requiring active DNA synthesis. METHODS: Rat FH were obtained using the nonperfusion collagenase/DNase digestion method. Free and cultured cells were studied using electron microscopy, fluorescence-activated cell sorting, and Northern analysis using alpha-fetoprotein and albumin as markers of hepatocyte lineage. DNA synthetic activity was measured in quiescent and mitogen stimulated fetal and adult hepatocytes by [3H]thymidine incorporation. Susceptibility of cultured FH to retrovirally mediated gene transfer was studied using an amphotropic retroviral vector carrying the Escherichia coli lac-Z gene. Nagase analbuminemic rats were used as recipients to study the effects of intraportal FH transplantation. Analysis of serum albumin was carried out by enzyme-linked immunosorbent assay. RESULTS: In fetal liver, 87+/-2% of the cells showed morphological and molecular features of hepatocytes. DNA synthetic activity in nonstimulated cultured FH was 10 times greater than the maximal hepatocyte growth factor-driven response in adult rat hepatocytes. A total of 5 15% FH stained positive for X-gal; results of transduction in adult hepatocyte cultures were negative. In Nagase analbuminemic rat recipients, FH produced significant amounts of albumin only when a hepatic regenerative stimulus was applied. Immunohistochemistry confirmed presence of albumin-positive hepatocytes. CONCLUSIONS: Fetal rat liver from the late gestation period is highly enriched with hepatocyte progenitors. They are highly proliferative and susceptible to retroviral transduction and can engraft and function in the adult rat liver if transplanted under a hepatic regenerative stimulus. PMID- 9371662 TI - Protective effects of dietary L-arginine supplementation on chronic cyclosporine nephrotoxicity. AB - BACKGROUND: L-Arginine (L-Arg), the substrate for nitric oxide (NO) synthase producing NO, and the NO synthase inhibitor, N-nitro-L-arginine-methyl ester (L NAME), have both been shown to modify acute cyclosporine (CsA)-induced intrarenal vasoconstriction. However, the mechanism of chronic CsA nephrotoxicity characterized by progressive tubulointerstitial fibrosis (TIF) remains unclear. Thus, we examined the pathogenetic role of NO in a rat model of chronic CsA nephropathy. METHODS: Rats were given vehicle, CsA (7.5 mg/kg), CsA + L-Arg (1.7 g/kg), CsA + D-arginine (1.7 g/kg), and CsA + L-NAME (3.5 mg/kg) for 28 days on a low-salt diet. NO production, glomerular filtration rate (GFR), blood and urine chemistry, and histology were assessed. RESULTS: L-Arg treatment significantly enhanced NO biosynthesis and protected animals from impaired GFR and development of TIF induced by CsA, whereas D-arginine did not. In contrast, L-NAME strikingly reduced urinary NO and worsened both GFR and TIF compared to the CsA alone group, whereas L-NAME did not change renal function and histology in the vehicle group. CONCLUSIONS: Chronic CsA nephrotoxicity can be aggravated by NO blockade and ameliorated by NO enhancement, suggesting that NO has an important role in the mechanism of chronic CsA nephropathy. PMID- 9371664 TI - Complement activation as a cause for primary graft failure in an isogeneic rat model of hypothermic lung preservation and transplantation. AB - Although agents that inhibit complement activation may be beneficial in discordant xenotransplantation, it is not known whether local complement activation occurs and is deleterious after isogeneic lung transplantation. Lungs were harvested from Lewis rats subjected to 4 degrees C 6-hr preservation followed by transplantation into strain-, gender-, and weight-matched recipients. Transplanted lungs demonstrated increased immunostaining for C5b-9 compared with nontransplanted controls, confirming local complement activation in this isograft model. To investigate the physiologic relevance of complement activation in the transplanted lung, the native pulmonary artery was ligated after transplantation, and pulmonary vascular resistance (mmHg/ml/min), arterial oxygenation (mmHg), graft neutrophil infiltration (myeloperoxidase activity, deltaAbs 460 nm/min), and recipient survival were measured at 30 min. Animals received either saline (control; n=22) or soluble complement receptor type-1 (sCR1, 15 mg/kg; n=19) 2 min before reperfusion. Animals treated with sCR1 showed a marked reduction in serum complement hemolytic activity (CH50; 90% lower than that of control animals, P<0.001). Compared with controls, sCR1-treated animals showed reduced pulmonary vascular resistance (2.9+/-1.1 vs. 8.5+/-1.5 mmHg/ml/min, P<0.05), improved arterial oxygenation (194+/-34 vs. 91+/-17 mmHg, P<0.05), decreased neutrophil infiltration (35% decrease, P<0.005), and improved recipient survival (74% vs. 23%, P<0.005). In parallel with the reduction in complement hemolytic activity in sCR1-treated animals, immunohistology of the transplanted lung revealed decreased C5b-9 deposition compared with controls. Taken together, these data indicate that complement activation occurs after lung preservation and transplantation in an isograft model, and that inhibiting complement activation improves outcome after transplantation. PMID- 9371665 TI - Delayed xenograft rejection of pig-to-baboon cardiac transplants after cobra venom factor therapy. AB - BACKGROUND: This study sought to (i) investigate the efficacy of cobra venom factor (CVF) in preventing hyperacute rejection (HAR) after pig-to-baboon heart transplantation, (ii) examine the effect of additional splenectomy (Spx) and pharmacologic immunosuppression (IS), and (iii) study delayed graft rejection when HAR is avoided by complement depletion. METHODS: Eleven recipient baboons received heterotopic pig heart transplants. Three received either no therapy or IS (cyclosporine + methylprednisolone +/- cyclophosphamide +/- methotrexate) at clinically well-tolerated doses, with graft survival for only 40, 32, and 15 min, respectively. Two received CVF+/-Spx, which extended survival to 5 and 6 days, respectively. Six underwent Spx + CVF therapy + IS; graft survival was 3 hr (technical complication), 6 days (death from sepsis), 10, 12, and 22 days (vascular rejection), and <25 days (euthanized for viral pneumonia with a functioning graft that showed histopathologic features of vascular rejection). RESULTS: Dense deposition of IgM and, to a lesser extent, IgG and IgA were seen on the endothelial cells within 1 hr of transplantation, but only trace levels of complement deposition were present in CVF-treated recipients. Within approximately 5-12 days, cardiac xenografts showed progressive infiltration by mononuclear cells, consisting primarily of activated macrophages producing tumor necrosis factor-alpha and small numbers of natural killer cells; T and B cells were absent. CONCLUSIONS: We conclude that (i) CVF prevents HAR, (ii) the addition of Spx + IS delays rejection, but (iii) the early deposition of antibody leads to progressive graft injury, resulting in (iv) delayed vascular rejection. Our findings indicate that the features of delayed xenograft rejection described in small animal models also occur in the pig-to-baboon model, and that rejection may occur in a complement-independent manner from the effects of antibody and/or host macrophages. PMID- 9371666 TI - Does transplantation produce quality of life benefits? A quantitative analysis of the literature. AB - BACKGROUND: Despite numerous reports published since the early 1970s, it is frequently asserted that quality of life (QOL) outcomes of transplantation have seldom been investigated and/or that little is known about QOL. This view may have persisted due to lack of adequate cumulation and synthesis of existing data. We performed an exhaustive, quantitative literature review to determine the nature and degree of any QOL benefits associated with transplantation in adults. METHODS: All independent, peer-reviewed empirical, English-language QOL studies were retrieved for six areas of transplantation: kidney, pancreas/combined kidney pancreas, heart, lung/combined heart-lung, liver, and bone marrow. Studies' findings were analyzed to determine whether the weight of evidence suggested that (a) QOL improved from pre- to posttransplant, (b) transplant recipient QOL was better than that of patient comparison groups, and (c) recipient QOL equaled that of healthy nonpatient samples. RESULTS: A total of 218 independent studies, evaluating a total of approximately 14,750 patients, were identified. The majority of studies demonstrated statistically significant (P<0.05) pre- to posttransplant improvements in physical functional QOL, mental health/cognitive status, social functioning, and overall QOL perceptions. The majority documented physical functional and global QOL advantages for transplant recipients relative to ill comparison groups. The studies did not indicate that recipient QOL in specific functional areas equaled that of healthy, nonpatient cohorts, although global QOL perceptions were often high. CONCLUSIONS: Although transplantation may not restore to the patient the "normal" life he/she may once have had, convergent evidence from six areas of transplantation, a variety of study designs, and demographically diverse study cohorts suggests that there are distinct QOL benefits of transplantation. Future work is required to identify background and personal factors that influence the degree of QOL benefits that any individual patient realizes from transplantation. PMID- 9371667 TI - Effect of HLA matching on the relative risk of mortality for kidney recipients: a comparison of the mortality risk after transplant to the mortality risk of remaining on the waiting list. AB - BACKGROUND: Patients must wait increasingly longer periods on the kidney waiting list (WL) before receiving a transplant. Although patients can be maintained on dialysis, many deaths occur while waiting. To determine whether the risk of mortality on the WL is different from that related to the transplant procedure, data from the Organ Procurement and Transplantation Network and Scientific Registry were used to analyze all adult patients entered on the United Network for Organ Sharing (UNOS) kidney WL for a primary transplant between April 1, 1994, and December 31, 1994 (n=9925). METHODS: To account for the time spent on the WL before transplant, a time dependent, nonproportional hazards model was used to assess the risk of mortality after transplant for both well-matched (zero to two HLA mismatches) and poorly-matched (three to six HLA mismatches) transplants compared with the mortality risk of remaining on the WL. This model incorporated an exponential decay component to account for the transient increased risk after kidney transplantation. Patients were stratified by age, race, creatinine level, panel-reactive antibody at listing, and blood group. RESULTS: Although there was an increased risk of mortality in the initial posttransplant period, the risk of mortality at 1 year for transplanted patients was 59% (three to six mismatches) to 67% (zero to two mismatches) less than that of patients who remained on the waiting list for an additional year. CONCLUSIONS: Kidney transplantation is more beneficial than remaining on the waiting list. Even poorly-matched kidneys provided a significant reduction in the risk of mortality by 6 months as compared with the mortality risk of continuing to wait. Patients receive the maximum benefit when transplanted with well-matched kidneys. PMID- 9371668 TI - Immunosuppressive therapy in high-risk transplant patients: dose-dependent efficacy of mycophenolate mofetil in African-American renal allograft recipients. U.S. Renal Transplant Mycophenolate Mofetil Study Group. AB - BACKGROUND: Numerous studies have demonstrated that renal allograft survival is reduced in African-Americans (AAs). This posthoc racial subgroup analysis (AAs vs. non-AAs) tested whether mycophenolate mofetil (MMF) might have favorable implications for the treatment of AA renal allograft recipients. METHODS: Patients received a triple therapy regimen of corticosteroids, cyclosporine, and azathioprine (AZA) 1-2 mg/kg/day, MMF 2 g/day (MMF 2 g), or MMF 3 g/day (MMF 3 g). RESULTS: AAs in the AZA group had the highest biopsy-proven rejection/treatment failure (BPR/TF) rate (57.5% vs. 43.5% for non-AAs). AAs in the MMF 3 g group showed a significant reduction in BPR/TF (57.5% vs. 24.2%, P=0.0008). BPRs were more frequent for AAs in either the AZA (47.5%) or MMF 2 g group (31.8%) than in the MMF 3 g group (12.1%), whereas rejections were reduced for non-AAs receiving either MMF dosage (AZA, 35.5%; MMF 2 g, 15.7%; MMF 3 g, 18.8%). AAs in the AZA group experienced BPR/TF earlier than AAs in the MMF 3 g group (median onset at 64 days vs. > 183 days, P=0.0012). But AAs in the MMF 3 g experienced BPR/TF the latest among the six subgroups of treatment and race. AAs had more severe rejection episodes and higher serum creatinine levels at 6 months after transplant, regardless of treatment group. CONCLUSIONS: Dose-dependent prevention of acute rejection in AAs is best afforded by a dosage of MMF at 3 g/day, whereas 2 g/day provides a superior benefit/risk ratio for non-AAs. MMF at 3 g/day thus provides an improvement over conventional immunosuppressive strategies in reducing the frequency of acute rejections in this immunologically high-risk group. PMID- 9371669 TI - Long-term renal function in type I diabetics after kidney or kidney-pancreas transplantation: influence of number, timing, and treatment of acute rejection episodes. AB - BACKGROUND: Previous studies comparing renal function in diabetic subjects receiving either a kidney or kidney-pancreas transplant generally have indicated no differences; however, these studies have been limited by inclusion of either a small number of patients or selected patients followed for relatively short periods of time. METHODS: To compare long-term renal function and factors affecting renal function in type I diabetic patients receiving either kidney or kidney-pancreas transplants, the slopes of regression lines generated by plotting the reciprocal of serum creatinine (1/Cr) versus time were measured in 109 consecutive patients followed for at least 12 and up to 102 months after transplantation. Multivariate analyses included linear regression using the slope of 1/Cr versus time as the dependent variable and logistic regression using a positive or negative slope as the dependent variable. RESULTS: Significant differences between kidney-pancreas (n=64) and kidney recipients (n=45) included a smaller proportion of African-Americans, lower rates of HLA matching, lower levels of panel-reactive antibodies, shorter cold ischemia times, a lower incidence of delayed graft function, and a higher incidence of acute renal allograft rejection episodes in the kidney-pancreas group. Trough cyclosporine blood levels were significantly higher in the kidney-pancreas group for the first 12 posttransplant months. The slopes of 1/Cr versus time were negative in each group with a trend toward a more negative slope in the kidney-pancreas group. Multivariate analyses indicated that a concomitant pancreas allograft did not influence long-term renal function. The total number of renal rejection episodes was the best independent predictor of a negative slope of 1/Cr versus time. However, use of OKT3 for the treatment of rejection within the first 3 months of transplantation exerted a surprisingly beneficial effect on long-term renal function, a phenomenon that was most apparent in the kidney-alone group. CONCLUSIONS: The frequency and timing of acute rejection episodes are more important than the influence of a simultaneously transplanted pancreatic allograft in determining long-term function of the transplanted kidney. A concerning trend toward late deterioration of renal function in kidney-pancreas recipients suggests that the benefits of sustained euglycemia, shorter cold ischemia times, lower rates of sensitization, and early use of OKT3 ultimately may be outweighed by the negative effects of more frequent renal rejection episodes. PMID- 9371670 TI - Outcomes in diabetic patients after simultaneous pancreas-kidney versus kidney alone transplantation. AB - BACKGROUND: Previous studies have identified more morbidity in simultaneous pancreas-kidney (SPK) transplant recipients compared with kidney alone (KA) recipients. With the development of novel immunosuppressive drugs, studies are needed to determine optimal treatment regimens in specific patient populations. METHODS: We retrospectively compared short-term outcome in diabetic patients receiving either SPK or KA transplantation from December 10, 1991, to July 31, 1996. The SPK recipients received either cyclosporine (CsA) + azathioprine (AZA), FK506+AZA, or FK506 + mycophenolate mofetil (MM). KA group patients received either CsA+AZA or CsA+MM. RESULTS: Recipients of SPK instead of KA transplants were younger, had a longer mean length of stay, had a decreased incidence of delayed graft function, and had more readmissions. There were no significant differences in serum creatinine at 1, 2, and 3 years after transplantation, number of rejection episodes and infections, incidence of kidney graft loss and patient death, and 1- and 3-year actuarial patient and kidney graft survival rates between the two groups. Diabetic SPK patients receiving FK506+MM had a higher mean 3-month creatinine clearance (calculated), compared with recipients of CsA+AZA or FK506+AZA. Diabetic patients after KA transplantation who received CsA+MM demonstrated fewer rejection episodes and graft losses, although differences did not reach statistical significance. CONCLUSIONS: (1) Diabetic SPK recipients have decreased rates of delayed graft function and more readmissions compared with diabetic KA recipients. (2) There is no difference in: serum creatinine levels up to 3 years after transplantation, number of rejection episodes or infections, and 1- and 3-year patient and graft survival rates between SPK and KA recipients. (3) Short-term outcome is improved in diabetic recipients of SPK and KA transplants receiving MM instead of AZA. PMID- 9371671 TI - Selective revascularization of hepatic artery thromboses after liver transplantation improves patient and graft survival. AB - BACKGROUND: Hepatic artery thrombosis (HAT) can be a devastating complication of orthotopic liver transplantation (OLT), but early diagnosis may allow successful revascularization and graft salvage. METHODS: We reviewed data on 1,026 liver transplants at our institution. For patients in whom HAT was diagnosed within 30 days after OLT, we recorded indications for ultrasonography and liver function tests at diagnosis, management of HAT, and graft and patient survival. RESULTS: Thirty-two patients (3.1%) developed HAT at 6.8+/-6.6 days (range, 1-29 days) after OLT. Twelve patients (37.5%) were asymptomatic at diagnosis. In 11 of these 12, HAT was diagnosed on routine duplex at 2.0+/-1.55 days after OLT; in the 12th patient, HAT was noted during re-exploration for unrelated bleeding on postoperative day 3. Eleven of 12 patients (91.6%) were revascularized; one patient (8.4%) received no treatment with no sequelae. Of the 11 who were revascularized, 9 (81.8%) had graft salvage and 2 (18.2%) received a second transplant, with one death. Twenty patients (62.5%) were symptomatic. In these 20, HAT was diagnosed at 9.85+/-6.93 days after OLT. Symptoms were: elevated liver function test results (serum glutamic oxaloacetic transaminase: 722+/-1792 U/ml, serum glutamic pyruvic transaminase: 678+/-963 U/ml, and bilirubin: 10.2+/ 6.2 mg/dl) in 13 patients (65%); bile leak in 4 patients (20%), and sepsis in 3 (15%). Five of the 20 patients (25%) were revascularized; of these 5, 2 (40%) had graft salvage, 2 (40%) received a second transplant with 1 death, and 1 (20%) died of a liver abscess. Twelve symptomatic patients (60%) had immediate re-OLT; 10/12 are alive, 1 died of sepsis, and 1 died late of unrelated causes. Three symptomatic patients had no treatment; two died of biliary sepsis and one survived. Overall graft salvage was 83.3% in asymptomatic patients and 15% in patients with symptoms (P<0.001). Graft salvage in asymptomatic patients undergoing revascularization was 81.8%, versus 40% in symptomatic patients (P=NS). One-year patient survival was 91.7% in asymptomatic patients and 65% in symptomatic patients (with one late death excluded) (P=NS). CONCLUSIONS: Routine postoperative duplex ultrasonography should be performed early after liver transplantation. We believe that emergent revascularization of hepatic artery thrombosis in asymptomatic patients and retransplantation in symptomatic patients lead to improved graft salvage and patient survival with a relatively low incidence of late biliary complications. PMID- 9371672 TI - Increased waiting time for liver transplantation results in higher mortality. AB - BACKGROUND: Waiting time to liver transplantation (LTx) has dramatically lengthened, but the proportion of candidates who die awaiting transplantation has not increased. We evaluated whether longer waiting time for LTx candidates increases mortality. METHODS: A cohort of candidates listed for LTx between 1990 and 1993 by three large transplantation programs was followed for 2 years. The exposure measure was ABO blood type, which is not inherently related to outcome, but is a major determinant of waiting time. The main outcome measure was 2-year mortality, as evaluated by logistic regression analysis that controlled for differences in clinical status at the time of evaluation for LTx. RESULTS: The 308 candidates with type O blood waited longer for LTx (median 109 days) than the 399 candidates with other blood types (median 58 days) (P=0.001). Candidates listed for LTx with type O blood had better clinical status at evaluation, but then had higher pretransplantation mortality (13.3%) than other candidates (7.0%) (P=0.005). Blood group O candidates had higher 2-year mortality (26.6%) than other candidates (22.1%), which on multivariate analysis resulted in a mortality odds ratio at 2 years of 1.52 (95% confidence interval=1.04-2.23). With the difference in median waiting time between blood groups increasing from 44 days in the first year to 108 days in the third year, the 2-year mortality odds ratio also rose from 0.94 to 1.97. CONCLUSIONS: When compared with LTx candidates with other blood types, blood type O candidates have longer waiting times and higher pretransplantation mortality, which results in higher 2-year mortality. PMID- 9371673 TI - The cytokine and histological response in islet xenograft rejection is dependent upon species combination. AB - BACKGROUND: Islet xenografts have clinical potential, may avoid hyperacute rejection, and therefore are a good place to examine the cellular xenograft immune response. The aim of this study was to examine the cellular, humoral, and cytokine response in islet xenograft rejection and to determine the difference in the immune response with a different donor species. METHODS: Two islet xenograft models (DA rat islets to B6AF1 mouse and canine islets to B6AF1 mouse) and a mouse syngeneic control model were examined histologically and by a semiquantitative polymerase chain reaction method. RESULTS: There was significant up-regulation of all intragraft cytokines tested (interleukin [IL]-2, IL-4, IL-5, IL-10, and interferon-gamma) in both xenograft models compared with the controls. However, the dog islet grafts had higher levels of IL-4 and IL-5 gene expression than the rat islet grafts, which, conversely, had higher levels of interferon gamma gene expression. These differences correlated with the histological and anti-donor antibody production differences between the two models. The dog to mouse model had an intense eosinophilic infiltrate and an early up-regulation of anti-donor antibody, whereas there was little eosinophilic infiltrate and a delayed anti-donor antibody up-regulation in the rat to mouse model. CONCLUSIONS: The mouse used different mechanisms to reject the rat and canine islets, suggesting that the immune response in islet xenograft rejection may be dependent on the species combination. It may not be possible to characterize the cellular xenograft rejection response in a bipolar manner as has been the case with humoral rejection response. Caution therefore needs to be taken before extrapolating the cellular immune responses seen in animal models to the clinical setting. PMID- 9371675 TI - Immunodominant minor histocompatibility antigen peptides presented by H2Db molecules. AB - BACKGROUND: C57BL/6 (B6) mice generate cytolytic T lymphocytes (CTLs) to a limited number of immunodominant cytotoxic T cell target (CTT) antigens and associated peptides when primed with H2-matched BALB.B spleen cells, despite multiple minor histocompatibility antigen (HA) differences. We previously showed that these CTLs recognize four Kb-bound minor HA peptides derived from CTT antigens. Here, we describe the identification of Db-bound minor HA peptides recognized by B6 anti-BALB.B CTLs. METHODS: Peptides were extracted from Db molecules immunoprecipitated from lysates of T lymphoblasts from BALB.B mice and mice from the CXB recombinant inbred strains that express H2b and segregate minor HA from BALB/c and B6. Peptides were separated by reverse-phase high-performance liquid chromatography and tested for sensitization of targets for lysis by CTLs specific for BALB.B and the CXB strains. RESULTS: B6 anti-BALB.B CTLs recognized a single Db-bound peptide whose distribution in CXB strains matched that of the previously reported CTT-1 minor HA. An additional Db-bound peptide (CTT-7) was recognized by B6 anti-CXBG CTLs. CTT-1 was expressed by independently derived inbred mouse strains that express H2b. CTT-1 was recognized by B6 CTLs specific for these inbred strains, except for the LP and 129 strains that stimulated CTL specific for the CTT-8 peptide expressed by these two strains. CONCLUSIONS: These results demonstrate that B6 CTLs primed and boosted with multiple minor HA recognize a maximum of two minor HA peptides regardless of the strain of origin of H2b-matched stimulating lymphoid cells. PMID- 9371674 TI - Species differences in the expression of major histocompatibility complex class II antigens on coronary artery endothelium: implications for cell-mediated xenoreactivity. AB - BACKGROUND: There is controversy in the literature as to whether swine coronary endothelium expresses major histocompatibility complex (MHC) class II antigens constitutively. METHODS: Because this issue has implications for cell-mediated human anti-swine xenogeneic responses, we stained tissue sections from human, pig, rat, and mouse hearts with the anti-class II monoclonal antibody ISCR3, which has a similar specificity and titer when binding to human, porcine, and rodent class II molecules. RESULTS: Immunoperoxidase staining of human and porcine hearts with ISCR3 resulted in a dense reaction on the coronary endothelium of epicardial arteries, intramuscular arterioles, and capillaries. In contrast, the coronary endothelium of rat and mouse hearts did not stain with ISCR3. When freshly harvested porcine aortic endothelial cells were placed in culture, class II MHC antigen expression was lost within three to four passages. CONCLUSIONS: Thus, using a single antibody with cross-species reactivities, we demonstrate that swine coronary endothelium, unlike rodent coronary arteries, expresses similar basal amounts of class II MHC antigens to human coronary vessels. The constitutive expression of class II MHC antigens on swine coronary artery endothelium may contribute to host T cell-mediated xenogeneic responses in clinical pig-to-human cardiac xenotransplantation and thus become a target for therapeutic intervention. PMID- 9371676 TI - Resting B cells as tolerogens in vivo but only for minor histocompatibility antigens: evidence for activation of resting B cells in vivo. AB - BACKGROUND: Small, resting B cells (rB cells) express major histocompatibility complex (MHC) class II molecules but not the putative costimulatory molecules, B7 1 (CD80) and B7-2 (CD86); they are classified as nonprofessional antigen presenting cells. rB cells have been shown to be capable of anergizing T cells in vitro and inducing the prolonged survival of skin grafts mismatched for a single minor histocompatibility (miH) antigen, H-Y. The aim of this study was to investigate ability of rB cells to induce unresponsiveness to multiple miH and MHC antigens. METHODS: Mice were pretreated with 1 x 10(7) donor rB cells 14 days before transplantation of cardiac grafts mismatched for either a single or multiple miH and/or MHC antigens in vivo. RESULTS: rB cells induced indefinite prolongation of cardiac grafts mismatched for H-Y antigen (C57BL/10 male to female). Moreover, 50% of grafts mismatched for multiple miH antigens (C3H to CBA) were accepted indefinitely in recipients treated with donor rB cells. In marked contrast, when grafts were mismatched for either a single MHC class I antigen, Kb (CBK to CBA), or multiple MHC and miH antigens (C57BL/10 to C3H), pretreatment with rB cells did not prolong graft survival. To investigate why rB cells were ineffective tolerogens for grafts mismatched for MHC antigens, we examined the fate of the cells in vivo. We demonstrate that, after intravenous injection of rB cells, expression of B7-2 was induced within 24 hr. CONCLUSIONS: These data suggest that rB cells may be less effective at inducing specific unresponsiveness to MHC antigens because of their rapid activation in vivo. PMID- 9371678 TI - Interleukin-12 prevents severe acute graft-versus-host disease (GVHD) and GVHD associated immune dysfunction in a fully major histocompatibility complex haplotype-mismatched murine bone marrow transplantation model. AB - BACKGROUND: We have recently reported that interleukin (IL)-12 prevents acute graft-versus-host disease (GVHD)-induced mortality in a full major histocompatibility complex- plus multiple minor antigen-mismatched A/J-->B10 bone marrow transplantation (BMT) model. Because most patients have access to a haploidentical, one haplotype-mismatched donor, we have now investigated the protective effect of IL-12 against GVHD and GVHD-associated immune dysfunction in a haploidentical CBD2F1 (H2kxd) --> B6D2F1 (H2bxd) strain combination. METHODS: GVHD was induced by injecting CBD2F1 marrow and spleen cells into lethally irradiated B6D2F1 mice. RESULTS: In untreated control mice, GVHD resulted in 87% mortality by day 8 after BMT, with no survivors beyond day 17. Treatment with a single injection of IL-12 on the day of BMT led to 87% long-term survival, with no significant weight loss, diarrhea or GVHD skin changes. The majority of T cells recovering in these mice showed the CD62L+, CD44low, CD45RBhigh naive phenotype. These T cells showed specific tolerance to both host and donor histocompatibility antigens, but normal anti-third party (H2s) alloresponses in vitro. B-cell proliferative responses to lipopolysaccharide were also normal in IL-12-protected mice. Moreover, normal negative selection of thymocytes bearing T cell receptors with Vbeta that recognize endogenous superantigens was observed among CD4+CD8- thymocytes, indicating a lack of GVHD-associated thymic selection abnormalities in IL-12-protected allogeneic BMT recipients. CONCLUSIONS: IL-12 provides permanent protection against an otherwise severe, rapidly lethal GVHD, with no clinical manifestations of chronic GVHD, immunosuppression or autoimmune features, in a full major histocompatibilty complex haplotype-mismatched murine BMT model. PMID- 9371677 TI - Presence of anti-FKBP12 autoantibodies in patients with liver allografts: its association with allograft rejection. AB - BACKGROUND: It was reported that autoantibodies against cyclophilin are present in sera from systemic lupus erythematosus. We hypothesized that autoantibodies against FKBP12, another immunophilin, may be present in the plasma of liver allograft recipients, which may affect the clinical outcome of liver allografts. METHODS: We investigated the relationship between the presence of anti-FKBP12 autoantibodies and rejection episodes in 47 patients treated with FK506 after living-related partial liver transplantation (LRLT). The patients consisted of two groups: 22 with rejection [R(+) group] and 25 without rejection [R(-) group]. The autoantibodies were measured by an indirect ELISA, and the specificity was confirmed by absorption with antigen and immunoblotting. RESULTS: The autoantibodies were detected in 13 of 22 in the R(+) group (IgG: 5; IgM: 6; both: 2) and in 6 of 25 in the R(-) group (IgG: 2; IgM: 3; both: 1) before LRLT (P=0.0193). After LRLT, they were also detected more frequently in the R(+) group (12 of 22; IgG: 1; IgM: 8; both: 3) than in the R(-) group (2 of 25; IgG: 1; IgM: 1) (P=0.001). In the R(+) group, the mortality of the patients who were positive and negative for the autoantibodies was 6 of 12 and 2 of 10, respectively. The autoantibodies were detected in all four patients with chronic or refractory acute rejection. The autoantibodies were not detected in any of the 34 healthy subjects. CONCLUSIONS: These results suggest that the presence of the autoantibodies in patients before transplantation is related to rejection, and the presence after transplantation may be associated with patient outcome. PMID- 9371679 TI - Measurement of cytotoxic T lymphocyte precursor frequencies reveals cryptic HLA class I mismatches in the context of unrelated donor bone marrow transplantation. AB - BACKGROUND: In this large, two-center study, 260 cytotoxic T lymphocyte precursor (CTLp) frequency assays, performed to assess patient-donor compatibility, were analyzed in relation to the degree of HLA matching. METHODS: While the tissue typing techniques used at the Royal Postgraduate Medical School (RPMS) and Anthony Nolan Bone Marrow Trust (ANBMT) differ, the results of the analyses on the two sites are analogous, with high CTLp frequencies (>1:100,000) in 42% and 41% of recipient-donor pairs, respectively. RESULTS: Recipient-donor combinations with class I mismatches and class II identity were associated with high CTLp frequencies (collectively 83% vs. 17% low CTLp). This correlation was not as strong in pairs where class II mismatches were demonstrated (61% high vs. 39% low). Despite using different matching procedures, the RPMS and ANBMT both show that 32% of the "perfectly" matched pairs (i.e., where no mismatch was detected by any of the techniques used here) had high frequencies of recipient-specific CTLp. CONCLUSIONS: The failure of conventional methods to identify such a level of histoincompatibilities indicates that the CTLp assay has an important role in the selection of unrelated donors for bone marrow transplantation. PMID- 9371680 TI - Thrombolysis and endovascular stent placement for inferior vena caval thrombosis in a liver transplant recipient. AB - BACKGROUND: Vascular complications remain an important cause of postoperative morbidity in liver transplant patients. Herein, we present an unusual case of nonanastomotic inferior vena cava (IVC) stenosis in a patient with a "piggyback" caval anastomosis. METHODS: A 59-year-old woman underwent liver transplantation using a piggyback IVC anastomosis. Her postoperative course was complicated by IVC thrombosis. Catheter-directed thrombolysis, followed by balloon angioplasty and intravascular stent placement, was used to recanalize the IVC and treat a severe retrohepatic IVC stenosis. RESULTS: After 46 hr of catheter-directed urokinase infusion, there was clot lysis and identification of a severe stenosis in the retrohepatic IVC. The lesion was extremely resistant to balloon dilatation alone and a 22-mm-diameter intravascular stent was placed. Simultaneous dilatation of three high-pressure balloons was necessary for maximal stent expansion. The patient remains asymptomatic with no evidence of IVC compromise through 20 months of follow-up. CONCLUSIONS: IVC stenosis and thrombosis after liver transplantation may be treated favorably in some patients using catheter directed thrombolytic therapy followed by balloon dilatation and/or stent placement. PMID- 9371681 TI - Anticardiolipin antibodies and hepatic artery thrombosis after liver transplantation. AB - BACKGROUND: Hepatic artery thrombosis (HAT) remains a devastating complication after liver transplantation. Various factors have been implicated in the pathogenesis of HAT, such as clotting abnormalities, increased hematocrit, and technical complications, but the role of anticardiolipin antibodies has not been evaluated. We investigated the possible association between HAT and anticardiolipin antibodies in adult patients who underwent liver transplantation. METHODS: Seven patients with HAT after orthotopic liver transplantation, 28 liver recipients without HAT, and 35 normal blood donors were evaluated. Determination of IgM and IgG anticardiolipin antibodies was performed by enzyme-linked immunosorbent assay using pretransplant serum from all allograft recipients. Clinical information was obtained from chart review. Fisher's exact test and Wilcoxon rank sum test were used for statistical analysis, and all P-values were two-tailed. RESULTS: Overall, 22 of 35 (63%) liver recipients had a positive anticardiolipin antibody test (either IgG or IgM titer >4 SD from the normal controls). The test was positive in 7 liver recipients (100%) with HAT compared with 15 out of 28 patients (54%) without HAT (P=0.031). As compared with liver recipients without HAT, patients with HAT also tended to have a higher mean anticardiolipin titer of IgG and IgM and a lower pretransplant platelet count; however, these differences were not significant. CONCLUSIONS: Our findings indicate that anticardiolipin antibodies are frequently elevated in patients with liver failure and may contribute to the pathogenesis of HAT after liver transplantation. Other potential consequences of anticardiolipin antibodies in end-stage liver disease remain to be determined. PMID- 9371682 TI - FK506 potentiates steroid-induced T-cell apoptosis. AB - BACKGROUND: FK506 and glucocorticoids are used for allograft rejection, graft versus-host disease, and autoimmune diseases. MATERIALS: We investigated the combined effect of FK506 and glucocorticoids on T-cell apoptosis. RESULTS: Dexamethasone injection in mice reduced the number of CD4+CD8+ thymocytes by increasing DNA fragmentation. Pretreatment with FK506 significantly augmented thymocyte DNA fragmentation induced by dexamethasone injection. Increased thymic apoptosis resulted in the disappearance of CD4+CD8+ thymocytes after FK506/dexamethasone injection. In addition to thymocytes, mature human peripheral blood T cells undergo apoptosis by exposure to dexamethasone in vitro. FK506 synergistically enhanced dexamethasone-mediated apoptosis of human peripheral blood T cells. CONCLUSIONS: Thus, our results showed that FK506 enhanced dexamethasone-induced apoptosis of T cells in vivo and in vitro. This interaction may enhance the therapeutic immunosuppression achieved by these two drugs. PMID- 9371683 TI - Influence of bacterial endotoxin on radiation-induced activation of human endothelial cells in vitro and in vivo: interleukin-10 protects against transendothelial migration. AB - To extend previous studies on the anti-inflammatory role of interleukin (IL)-10 in vivo, mice pretreated with IL-10 were subjected to ionizing radiation (IR), lipopolysaccharide (LPS), or both and assessed for the expression of the intercellular adhesion molecule 1 (ICAM-1) in immunohistochemical analyses. IL-10 was able to almost fully protect LPS+IR-treated animals against ICAM-1 up regulation. Because LPS and IR also increased adhesion of peripheral blood mononuclear cells, transendothelial migration assays were performed to investigate the functional significance of these findings. IR was found to induce transendothelial migration, and this effect could be enhanced by cotreatment with LPS, in the same fashion as peripheral blood mononuclear cell adhesion. Also in this system, IL-10 proved to act as a potent LPS antagonist. Finally, in vivo immunohistochemical analyses revealed an infiltration of CD3+ T lymphocytes into organs that were the target of transplant-related complications after LPS+IR treatment. This infiltration could also be completely reversed by IL-10 pretreatment. PMID- 9371684 TI - Insurability of kidney donors. PMID- 9371686 TI - Experimental evidence for the essential role of the C-terminal residue in the strict aminopeptidase activity of the thiol aminopeptidase PepC, a bacterial bleomycin hydrolase. AB - PepCs isolated from lactic acid bacteria and bleomycin hydrolases of eukaryotic organisms are strict aminopeptidases which belong to the papain family of thiol peptidases. The structural basis of the enzymic specificity of the lactococcal PepC has been investigated by site-directed mutagenesis. The deletion of the C terminal residue (Ala-435) abolished the aminopeptidase activity, whereas this deletion led to a new peptidase specificity. The enzymic properties of wild-type and mutant PepCs demonstrate that the terminal alpha-carboxy group plays a key role in the strict aminopeptidase activity. PMID- 9371687 TI - Allosteric modulation of rat brain nitric oxide synthase by the pterin-site enzyme inhibitor 4-aminotetrahydrobiopterin. AB - We investigated the functional and allosteric effects of the 4-amino analogue of tetrahydrobiopterin, (6R)-2,4-diamino- 5,6,7,8-tetrahydro-6-(L-erythro-1,2 dihydroxypropyl) pteridine (4-amino-H4biopterin) on pteridine-free rat neuronal nitric oxide synthase. In the presence of added (6R)-5,6,7,8-tetrahydro-L erythrobiopterin (H4biopterin; 10 microM), 4-amino-H4biopterin completely inhibited the conversion of both L-arginine and NG-hydroxy-L-arginine with half maximally effective concentrations of 1.1+/-0.09 and 1.3+/-0.09 microM, respectively. Inhibition was reversible, as shown by a time-dependent restoration of citrulline formation upon dilution of the inhibitor-treated enzyme (t1/2=3.0 min). Binding of 4-amino-H4biopterin led to a complete conversion of the haem from low-spin to high-spin state, and to the formation of stable homodimers which partially survived electrophoresis under denaturating conditions. These results show that oxidation of both L-arginine and NG-hydroxy-L-arginine is pteridine dependent, and that the allosteric effects of H4biopterin do not fully explain the essential role of the pteridine cofactor in nitric oxide biosynthesis. PMID- 9371685 TI - Molecular mechanisms for the control of translation by insulin. AB - Insulin acutely stimulates protein synthesis in mammalian cells, and this involves activation of the process of mRNA translation. mRNA translation is a complex multi-step process mediated by proteins termed translation factors. Several translation factors are regulated in response to insulin, often as a consequence of changes in their states of phosphorylation. The initiation factor eIF4E binds to the cap structure at the 5'-end of the mRNA and mediates assembly of an initiation-factor complex termed eIF4F. Assembly of this complex can be regulated by eIF4E-binding proteins (4E-BPs), which inhibit eIF4F complex assembly. Insulin induces phosphorylation of the 4E-BPs, resulting in alleviation of the inhibition. This regulatory mechanism is likely to be especially important for the control of the translation of specific mRNAs whose 5'-untranslated regions (5'-UTRs) are rich in secondary structure. Translation of another class of mRNAs, those with 5'-UTRs containing polypyrimidine tracts is also activated by insulin and this, like phosphorylation of the 4E-BPs, appears to involve the rapamycin-sensitive signalling pathway which leads to activation of the 70 kDa ribosomal protein S6 kinase (p70 S6 kinase) and the phosphorylation of the ribosomal protein S6. Overall stimulation of translation may involve activation of initiation factor eIF2B, which is required for all initiation events. This effect is dependent upon phosphatidylinositol 3-kinase and may involve the inactivation of glycogen synthase kinase-3 and consequent dephosphorylation of eIF2B, leading to its activation. Peptide-chain elongation can also be activated by insulin, and this is associated with the dephosphorylation and activation of elongation factor eEF2, probably as a consequence of the insulin-induced reduction in eEF2 kinase activity. Thus multiple signalling pathways acting on different steps in translation are involved in the activation of this process by insulin and lead both to general activation of translation and to the selective regulation of specific mRNAs. PMID- 9371688 TI - Constitutive internalization of cystic fibrosis transmembrane conductance regulator occurs via clathrin-dependent endocytosis and is regulated by protein phosphorylation. AB - Although the cystic fibrosis transmembrane conductance regulator (CFTR) is primarily implicated in the regulation of plasma-membrane chloride permeability, immunolocalization and functional studies indicate the presence of CFTR in the endosomal compartment. The mechanism of CFTR delivery from the cell surface to endosomes is not understood. To delineate the internalization pathway, both the rate and extent of CFTR accumulation in endosomes were monitored in stably transfected Chinese hamster ovary (CHO) cells. The role of clathrin-dependent endocytosis was assessed in cells exposed to hypertonic medium, potassium depletion or intracellular acid-load. These treatments inhibited clathrin dependent endocytosis by >90%, as verified by measurements of 125I-transferrin uptake. Functional association of CFTR with newly formed endosomes was determined by an endosomal pH dissipation protocol [Lukacs, Chang, Kartner, Rotstein, Riordan and Grinstein (1992) J. Biol. Chem. 267, 14568-14572]. As a second approach, endocytosis of CFTR was determined after cell-surface biotinylation with the cleavable sulphosuccinimidyl-2-(biotinamido)ethyl-1,3-dithio- propionate. Both the biochemical and the functional assays indicated that arresting the formation of clathrin-coated vesicles inhibited the retrieval of the CFTR from the plasma membrane to endosomes. An overall arrest of membrane traffic cannot account for the inhibition of CFTR internalization, since the fluid-phase endocytosis was not effected by the treatments used. Thus the efficient, constitutive internalization of surface CFTR (5% per min) occurs, predominantly by clathrin-dependent endocytosis. Stimulation of protein phosphorylation by cAMP-dependent protein kinase A and by protein kinase C decreased the rate of internalization of cell-surface biotinylated CFTR, and contributed to a substantial diminution of the internal CFTR pool compared with that of unstimulated cells. These results suggest that the rate of CFTR internalization may participate in the determination of the CFTR channel density, and consequently, of the cAMP-stimulated chloride conductance of the plasma membrane. PMID- 9371689 TI - Inhibition of nitric oxide synthase expression by PPM-18, a novel anti inflammatory agent, in vitro and in vivo. AB - We studied the effect of PPM-18, a chemically synthesized naphthoquinone derivative and also an anti-inflammatory agent, on the lipopolysaccharide (LPS) activated inducible NO synthase (iNOS) expression in rat alveolar macrophages. Pretreatment of macrophages with PPM-18 (0.1-10 microM) significantly inhibited nitrite production, iNOS protein expression and iNOS mRNA accumulation. PPM-18 did not directly affect the enzymic activities of iNOS and other constitutive NOS forms. The LPS-induced increase in nuclear transcription factor kappaB (NF kappaB) p65 and p50 in nucleus was suppressed by PPM-18 (10 microM). Moreover electrophoretic mobility-shift assays demonstrated that PPM-18 inhibited DNA binding to NF-kappaB induced by LPS in whole cells but not when added in the nuclear extract, suggesting that PPM-18 did not interfere directly with the binding of NF-kappaB to DNA and that some events had to be processed before NF kappaB could bind DNA. Examination of NF-kappaB showed that PPM-18 stabilized the NF-kappaB inhibitor, IkappaBalpha, by preventing its degradation from NF-kappaB. Therefore the stabilization of IkappaBalpha might have contributed to the inhibition of NF-kappaB activation. These results also indicate strongly that NF kappaB is involved in the production of NO on stimulation by LPS. PPM-18 significantly decreased the production of tumour necrosis factor alpha in response to LPS. PPM-18 protects mice against LPS-induced lethal toxicity. These results also indicate that PPM-18 is a potent inhibitor of iNOS expression by blocking the binding of NF-kappaB to promoter and exerts a beneficial effect in the mouse model of sepsis. PMID- 9371690 TI - Ca2+ transport by the luminal membrane of the distal nephron: action and interaction of protein kinases A and C. AB - We previously reported that parathyroid hormone and calcitonin increase Ca2+ uptake by purified distal luminal membranes. This effect is mimicked by high concentrations of cAMP. However, both hormones stimulate adenylate cyclase and phospholipase C. The purpose of the present study was to investigate the role of the phospholipase C pathway in the hormone action, and the interrelationship between the two messengers. Distal tubules from rabbit kidneys were incubated with dibutyryl cAMP (dbcAMP) or PMA, or both, and Ca2+ uptake by purified luminal membranes was measured by the rapid filtration technique. Incubation of the distal tubules with 1 mM dbcAMP significantly increased Ca2+ transport by the luminal membranes. A dose-response curve showed a half-maximal stimulation with 0.82 mM dbcAMP. In contrast, treatment of the tubules with 10 nM, 100 nM or 1 microM PMA did not influence Ca2+ uptake by these membranes. However, the addition of 100 nM PMA to low concentrations of dbcAMP strongly increased this uptake. The presence of cAMP or protein kinase C inhibitors prevented the effects of either a high concentration of dbcAMP alone or a low concentration of dbcAMP combined with 100 nM PMA. Our laboratory has already reported that Ca2+ uptake by the distal luminal membranes displays two-component kinetics. dbcAMP increased the Vmax of the low-affinity component, whereas a combination of the two messengers stimulated the Vmax of both the low- and high-affinity components. From these results, we conclude that: (1) in the distal tubule cells, activation of both protein kinases A and C is necessary for the stimulation of Ca2+ transport by the luminal membrane; (2) the combined effect of protein kinases A and C involves both components of the Ca2+-transport kinetics. PMID- 9371691 TI - Recombinant 2-enoyl-CoA hydratase derived from rat peroxisomal multifunctional enzyme 2: role of the hydratase reaction in bile acid synthesis. AB - Rat liver peroxisomes contain two multifunctional enzymes: (1) perMFE-1 [2-enoyl CoA hydratase 1/Delta3,Delta2-enoyl-CoA isomerase/(S)-3-hydroxyacyl-CoA dehydrogenase] and (2) perMFE-2 [2-enoyl-CoA hydratase 2/(R)-3-hydroxyacyl-CoA dehydrogenase]. To investigate the role of the hydratase activity of perMFE-2 in beta-oxidation, a truncated version of perMFE-2 was expressed in Escherichia coli as a recombinant protein. The protein catalyses the hydration of straight-chain (2E)-enoyl-CoAs to (3R)-hydroxyacyl-CoAs, but it is devoid of hydratase 1 [(2E) enoyl-CoA to (3S)-hydroxyacyl-CoA] and (3R)-hydroxyacyl-CoA dehydrogenase activities. The purified enzyme (46 kDa hydratase 2) can be stored as an active enzyme for at least half a year. The recombinant enzyme hydrates (24E) 3alpha,7alpha,12alpha-trihydroxy- 5beta-cholest-24-enoyl-CoA to (24R,25R) 3alpha,7alpha,12alpha, 24-tetrahydroxy-5beta-cholestanoyl-CoA, which has previously been characterized as a physiological intermediate in bile acid synthesis. The stereochemistry of the products indicates that the hydration reaction catalysed by the enzyme proceeds via a syn mechanism. A monofunctional 2 enoyl-CoA hydratase 2 has not been observed as a wild-type protein. The recombinant 46 kDa hydratase 2 described here survives in a purified form under storage, thus being the first protein of this type amenable to application as a tool in metabolic studies. PMID- 9371692 TI - Extracellular sphingosine 1-phosphate stimulates formation of ethanolamine from phosphatidylethanolamine: modulation of sphingosine 1-phosphate-induced mitogenesis by ethanolamine. AB - In this work, we determined the effects of sphingosine 1-phosphate (S1P) on phospholipase D (PLD)-mediated hydrolysis of phosphatidylethanolamine (PtdEtn), and evaluated the effects of the water-soluble product ethanolamine on S1P induced DNA synthesis in NIH 3T3 cells. In [14C]ethanolamine-labelled cells, S1P (0.5-5 microM) stimulated PLD-mediated hydrolysis of PtdEtn 1.5-2.1-fold. Down regulation of protein kinase C by chronic (24 h) treatment of cells with 300 nM PMA, or pretreatments (10 min) with the cell-permeant calcium chelator 1,2-bis-(O aminophenoxy)-ethane-N,N, N',N'-tetra-acetic acid tetra-acetoxymethyl ester led to the inhibition of S1P-induced PtdEtn hydrolysis. S1P alone was a weak inducer of DNA synthesis, but its effects were enhanced by phosphocholine (PCho), insulin, ATP or PMA. Ethanolamine (5-100 microM) did not modify the mitogenic effect of S1P alone, whereas at 50-100 microM concentrations it actually enhanced the mitogenic effect of PCho via a mitogen-activated protein (MAP) kinase independent mechanism. In contrast, 5-20 microM concentrations of ethanolamine, which correspond to normal blood ethanolamine levels in humans, strongly inhibited DNA synthesis induced by S1P plus PCho via a MAP kinase-dependent mechanism; importantly, less or no inhibition was observed with 50-100 microM concentrations of ethanolamine. At 5-50 microM concentrations, ethanolamine also inhibited the synergistic mitogenic effects of both S1P plus insulin (22-27% inhibition) and PCho plus ATP (45-73% inhibition) but not those of S1P plus PMA or S1P plus ATP. The results indicate that S1P stimulates PLD-mediated hydrolysis of PtdEtn by a mechanism that may involve a regulatory protein kinase C isoform. Increased formation of ethanolamine by PLD-mediated PtdEtn hydrolysis or by other means may be required for maximal stimulation of DNA synthesis by S1P in the presence of insulin, and particularly PCho. PMID- 9371693 TI - The 3'-untranslated region of the mouse cholesterol 7alpha-hydroxylase mRNA contains elements responsive to post-transcriptional regulation by bile acids. AB - To investigate the importance of the 3'-untranslated region (UTR) of the mouse cholesterol 7alpha-hydroxylase (cyp7) mRNA in post-transcriptional regulation of expression of the cyp7 gene, chimaeric genes encoding mRNA containing the structural sequence of chloramphenicol acetyltransferase (CAT) linked to either the 3'-UTR of the mouse cyp7 mRNA or the SV40 early gene mRNA were constructed. The human cytomegalovirus (CMV) promoter was used to drive the expression of all the chimaeric genes. Thus the transgenes had identical sequences in the promoter, the regions encoding the 5'-UTR and translated sequence but differed in the region encoding the 3'-UTR of their respective mRNA species. The transgene containing the entire cyp7 3'-UTR (designated CMV.CAT.CYP7) gave rise to CAT activity in transfected hepatoma cells that was one-quarter of that obtained in cells transfected with the transgene containing the SV40 3'-UTR (designated CMV.CAT.SV40). The 3'-UTR of the cyp7 mRNA contains sequences resembling AU-rich elements (AREs). Deleting eight of nine putative AREs from the CYP7 3'-UTR sequence increased the CAT activity to a level greater than that observed for CMV.CAT. SV40, whereas deletion of the intron region had no effect. These results show that the AREs of the 3'-UTR of the cyp7 mRNA decrease transgene expression. Bile acids are known to repress the expression of the cyp7 gene. To test whether the 3'-UTR of the cyp7 mRNA has a role in this process, the expression of the chimaeric genes was evaluated in hepatoma cells competent for bile acid uptake. Conjugated bile acids, but not unconjugated bile acids, further decreased the expression of the CMV.CAT.CYP7 transgene. The same bile acids had no effect on the expression of the CMV.CAT.SV40 transgene. Deletion of the intron from the cyp7 sequence did not alter the CAT activity compared with the parental plasmid, and also did not alter the sensitivity of the transgene to the conjugated bile acids. Deletion of the AREs from the cyp7 3'-UTR, which increased the expression of the transgene, did not abolish the sensitivity of the transgene to repression by conjugated bile acids. Thus the 3'-UTR of the mouse cyp7 mRNA also contains elements that facilitate the further repression of transgene expression in the presence of conjugated bile acids. The results indicate that the 3'-UTR of the mouse cyp7 mRNA contains information specifying regulation at the post transcriptional level. PMID- 9371694 TI - Chromatin structure of the Saccharomyces cerevisiae DNA topoisomerase I promoter in different growth phases. AB - We have determined the chromatin organization of the Saccharomyces cerevisiae DNA topoisomerase I promoter. Three nucleosomal core particles have been mapped at nucleotide level over the promoter region, encompassing the presumptive TATA sequence and the two RNA initiation sites; the most upstream nucleosome particle forms on to a 29 bp-long poly(dA-dT) element. This simple organization remains constant throughout both the logarithmic and the linear phase of growth, with the exception of an increased accessibility to micrococcal nuclease of the nucleosome covering the TATA box and the RNA initiation sites during the diauxic shift (the switching from the fermentative to the respiratory metabolism) in parallel with an increase of the DNA topoisomerase I mRNA. In addition, a strong disorganization of the bulk chromatin structure in the late stationary phase is also reported. PMID- 9371695 TI - Reconstitution of native-like nucleosome core particles from reversed-phase-HPLC fractionated histones. AB - We have reconstituted nucleosome core particles from reversed-phase-HPLC-purified chicken erythrocyte core histones and 145 bp random-sequence DNA fragments. Characterization of the resulting nucleoprotein complexes by sedimentation velocity, CD and DNase I footprinting showed that they are structurally indistinguishable from native nucleosome core particles. Furthermore, we have shown that the ability to reproduce these native-like structural features in these reconstituted nucleosome core particles is basically independent of the biological source or the method used (i.e. salt versus acid) for the extraction of histones before their HPLC fractionation. The usefulness and relevance of this approach for the reconstitution of native-like chromatin structures from histone types (histone variants/post-translationally modified histones), which are usually available only in relatively small amounts, is discussed. PMID- 9371696 TI - High-density-lipoprotein subfraction 3 interaction with glycosylphosphatidylinositol-anchored proteins. AB - To elucidate further the binding of high-density-lipoprotein subfraction 3 (HDL3) to cells, the involvement of glycosylphosphatidylinositol-anchored proteins (GPI proteins) was studied. Treatment of cultured cells, such as fibroblasts or SK-MES 1 cells, with a phosphatidylinositol-specific phospholipase C (PI-PLC) significantly decreases specific HDL3 binding. Moreover, PI-PLC treatment of cultured cells or cellular plasma membrane fractions results in releasing proteins. These proteins have a soluble form and can also bind HDL3, as revealed by ligand blotting experiments with HDL3. In order to obtain enriched GPI proteins, we used a detergent-free purification method to prepare a caveolar membrane fraction. In the caveolar fraction, we obtained, by ligand blotting experiments, the enrichment of two HDL3-binding proteins with molecular masses of 120 and 80 kDa. These proteins were also revealed in a plasma membrane preparation with two other proteins, with molecular masses of 150 and 104 kDa, and were sensitive to PI-PLC treatment. Electron microscopy also showed the binding of Au-labelled HDL3 inside the caveolar membrane invaginations. In SK-MES 1 cells, HDL3 are internalized into a particular structure, resulting in the accumulation and concentration of such specific membrane domains. To sum up, a demonstration has been made of the implication of GPI-proteins as well as caveolae in the binding of HDL3 to cells. PMID- 9371697 TI - Kinase-related protein (telokin) is phosphorylated by smooth-muscle myosin light chain kinase and modulates the kinase activity. AB - Telokin is an abundant smooth-muscle protein with an amino acid sequence identical with that of the C-terminal region of smooth-muscle myosin light-chain kinase (MLCK), although it is expressed as a separate protein [Gallagher and Herring (1991) J. Biol. Chem. 266, 23945-23952]. Here we demonstrate that telokin is also similar to smooth-muscle myosin regulatory light chain (ReLC) not only in its gross physical properties but also as an MLCK substrate. Telokin was slowly phosphorylated by MLCK in the presence of Ca2+ and calmodulin and could be readily dephosphorylated by myosin light-chain phosphatase. A threonine residue was phosphorylated with up to 0.25 mol/mol stoichiometry. This low stoichiometry, together with the observed dimerization of telokin [Sobieszek and Nieznanski (1997) Biochem. J. 322, 65-71], indicates that the telokin dimer was acting as the substrate with a single protomer being phosphorylated. Our enzyme kinetic analysis of the phosphorylation reaction confirms this interpretation. Because telokin phosphorylation also required micromolar concentrations of MLCK, which also facilitates the formation of kinase oligomers, we concluded that the oligomers are interacting with telokin. Thus it seems that telokin modulates the phosphorylation rate of myosin filaments by a mechanism that includes the direct or indirect inhibition of the kinase active site by the telokin dimer, and that removal of the inhibition is controlled by slow phosphorylation of the telokin dimer, which results in MLCK dimerization. PMID- 9371698 TI - Molecular cloning, sequencing and functional study of the promoter region of the human alpha2C4-adrenergic receptor gene. AB - Screening of a human foetal brain genomic DNA library allowed us to isolate an EcoRI-EcoRI fragment containing 6 kb of the 5'-flanking region, the open reading frame and 4 kb of the 3'-flanking region of the alpha2C4 gene. Analysis of the sequenced region (4850 bp) revealed that the first 900 bp 5' to the start codon are very rich in GC (84%), contain several Sp1-binding sites and lack a consensus TATA box. The 5'- and 3'-ends of the alpha2C4 transcript were determined by RNase protection assays carried out with a series of antisense probes. The data obtained with cellular RNA from HepG2 cells demonstrated that transcription is initiated 891 bases upstream of the translation-start site and that the polyadenylation site is located 550 bases downstream of the stop codon. These results are consistent with the existence of a non-conventional TATA box (TTAGAAA) and the presence of a unique polyadenylation signal (AATAAA). They also fit with the size of alpha2C4-RNA found by Northern-blot analysis (2.9 kb). The transcriptional activity of the alpha2C4 promoter region was investigated by transfecting several cell types with chimaeric constructs containing various fragments of the 5'-non-coding region and luciferase as a reporter gene. The activity of the construct containing the entire 5'-non-coding region appeared to depend on the host cell. Removal of the 5'-untranslated region resulted in loss of cell specificity and a concomitant increase in luciferase activity. Transfection of HepG2 and SK-N-MC cells with constructs deleted of additional 5' flanking fragments permitted the definition of a minimal 200 bp promoter fragment containing the pseudo-TATA box and two putative SP1-binding sites. PMID- 9371699 TI - Iron release from recombinant N-lobe and single point Asp63 mutants of human transferrin by EDTA. AB - Transferrins bind ferric ion and deliver the iron to cells. The mechanism of the iron release has been studied kinetically, in vitro, with the aid of single point mutants in which the iron-binding ligand, Asp63 (aspartic acid-63, D63), has been changed to Ser, Asn, Glu and Ala. Iron release from the unmutated N-lobe of human serum transferrin (hTF/2N) by EDTA is influenced by a variety of factors. The rate-determining conformational-change mechanism may be a major pathway for iron release from hTF/2N's having a 'closed' conformation, which leads to a saturation kinetic mode with respect to ligand concentration. The effect of chloride depends on the protein conformation, showing a negative action in the case of tight binding and a positive action when the protein has an 'open' or 'loose' conformation. The negative effect of chloride could originate from the binding competition between chloride and the chelate to the active site for iron release, and the positive effect could derive from the synergistic participation of chloride in iron removal. The 'open' conformation may be induced by decreasing pH: the transitional point appears to be at about pH 6.3 for the wild-type hTF/2N; the 'loose' conformation may be facilitated by mutations at D63, which result in the loss of a key linking component in interdomain interactions of the protein. In the latter case, structural factors dominate over other potential negative effects because the weak interdomain contacts derived from the mutation of D63 cause the binding site to open easily, even at pH 7.4. Therefore chloride exhibits an accelerating action on iron release by EDTA from all the D63 mutants. PMID- 9371701 TI - Characterization of the promoter of human adipocyte hormone-sensitive lipase. AB - Hormone-sensitive lipase (HSL) catalyses the rate-limiting step of adipose tissue lipolysis. The human HSL gene is composed of nine exons encoding the adipocyte form and a testis-specific coding exon. Northern blot analyses showed that human adipocytes express a 2.8 kb HSL mRNA, suggesting the presence of a short (20-150 bp) 5' untranslated region (5'-UTR). A single 5'-UTR of approx. 70 nt was detected in RNase H mapping experiments. Two 5'-UTRs of 70 and 170 nt respectively were obtained by rapid amplification of cDNA ends and cDNA library screenings. RNase protection experiments, with probes derived from the two products, showed that human adipocyte HSL mRNA contains only the 70 nt product. Primer extension analysis mapped the transcriptional start site 74 nt upstream of the start codon. In HT29, a human cell line expressing HSL, the presence of the short or the long 5'-UTR is mutually exclusive. The short and long 5'-UTR exons were located 1.5 and approx. 13 kb respectively upstream of the first coding exon. Various portions of the 5'-flanking region upstream of the short product exon were linked to the luciferase gene and transfected into cells that express HSL (HT29 cells and rat adipocytes) and do not express HSL (HeLa cells). High luciferase activity was found for constructs containing the sequence between nt 2400 and -86, but not for shorter constructs. An analysis of 14 kb of genomic sequence revealed the presence of five DNase I hypersensitive sites associated with active gene transcription. Three of the sites are located in the vicinity of the transcriptional start site and could be linked to the minimal promoter activity. Two of the sites are located downstream of the exon containing the start codon, suggesting the presence of intronic regulatory elements. PMID- 9371700 TI - Relocation of annexin V to platelet membranes is a phosphorylation-dependent process. AB - Annexins are a family of calcium-binding proteins that have been implicated in a wide range of intracellular processes. We have previously reported that stimulation of platelets with agents that increase intracellular [Ca2+] induces the relocation of annexin V to membranes, and that this annexin V may be binding to a 50 kDa protein located within platelet membranes. We report here, using an in vitro reconstitution system, that the relocation of annexin V to membranes is enhanced by ATP. We also demonstrate that when adenosine 5'-[gamma-thio] triphosphate, which can replace ATP in phosphorylation reactions, is substituted for ATP, the amount of annexin V that binds to membranes is further increased. In separate experiments using intact cells, we show that the protein phosphatase inhibitor okadaic acid mimics the action of the physiological agonist thrombin, in that it induces annexin V to bind to membranes and that the addition of the protein kinase inhibitor staurosporine inhibits A23187-induced relocation of annexin V. In addition, alkaline phosphatase, when added to isolated membranes, was found to remove endogenous annexin V from the membranes. Furthermore, immunoprecipitation of 33P-labelled proteins indicated that annexin V may form a multi-protein complex including phosphoproteins of 25, 50 and 83 kDa. Taken together these observations suggest that, following physiological activation, the phosphorylation of one or more proteins is responsible for the tight association of annexin V with platelet membranes and the subsequent regulation of membrane localized processes. PMID- 9371703 TI - Characterization of S-hexylglutathione-binding proteins of human hepatocellular carcinoma: separation of enoyl-CoA isomerase from an Alpha class glutathione transferase form. AB - Recent studies have revealed binding of mitochondrial enoyl-CoA isomerase (ECI) to S-hexylglutathione-Sepharose, an affinity matrix used for purification of glutathione transferases (GSTs), and the enzyme has been suggested to be identical with the Alpha class form of GST with a subunit molecular mass of about 30 kDa. In the present study, S-hexylglutathione-binding proteins of human hepatocellular carcinomas were characterized to examine their identity. Supernatant fractions of carcinoma and surrounding tissues were applied to an affinity column, and bound fractions were resolved into three proteins with subunit molecular masses/pI values of 33 kDa/7.0, 30 kDa/5.8 and 29 kDa/5.8 in addition to the well-characterized four GST subunits, A1, A2, M1 and P1, by two dimensional gel electrophoresis. The proteins were further purified by chromatofocusing at pH 7.4-4.0. The 30 and 29 kDa proteins were eluted at pH 4.9 and by 1 M NaCl respectively, and could be clearly separated from each other. The 29 kDa protein exhibited a low but significant activity towards 1-chloro-2,4 dinitrobenzene (4.25 micromol/min per mg of protein) and reacted with anti-(GST A1-2) antibody, suggesting that it is a member of the GST Alpha class. The 30 kDa protein did not react with anti-GST antibodies and was identified as ECI by immunoblotting and N-terminal-amino-acid-sequencing analyses. The results thus indicated that the Alpha class GST form composed of the 29 kDa subunits and ECI are two different proteins. The 33 kDa protein was eluted from the chromatofocusing column at pH 7.0 and did not react with either anti-GST antibodies or antibodies against mitochondrial enzymes involved in the beta oxidation of fatty acids. However, it exhibited a carbonyl reductase activity with menadione and ubiquinone, and amino acid sequences of its peptides cleaved by Staphylococcus aureus V8 proteinase were consistent with those reported for the enzyme. Thus this protein binding to S-hexylglutathione-Sepharose was identified as carbonyl reductase. PMID- 9371702 TI - Evidence that a low-molecular-mass GTP-binding protein is required for store activated Ca2+ inflow in hepatocytes. AB - The roles of a monomeric GTP-binding regulatory protein in the activation of store-activated plasma membrane Ca2+ channels and in the release of Ca2+ from the smooth endoplasmic reticulum (SER) in rat liver parenchymal cells were investigated with the use of freshly isolated rat hepatocytes and rat liver microsomes. A low concentration (approx. 130 microM intracellular) of guanosine 5'-[gamma-thio]triphosphate (GTP[S]) activated Ca2+ inflow in intact hepatocytes in the absence of an agonist, whereas a high concentration (approx. 530 microM intracellular) of GTP-S- or guanosine 5'-[betagamma-imido]triphosphate (p[NH]ppG) inhibited the Ca2+ inflow induced by inhibitors of the activity of the endoplasmic-reticulum Ca2+-ATPase (SERCA) and by vasopressin. GTP (530 microM) prevented the inhibition of Ca2+ inflow by GTP-S- and p[NH]ppG. Brefeldin A and the peptide human Arf-1-(2-17), which inhibit many functions of ADP ribosylation factor (Arf) proteins, inhibited the Ca2+ inflow induced by SERCA inhibitors and vasopressin, and altered the profile of Ca2+ release from the SER. These effects were observed at concentrations of Brefeldin A and Arf-1-(2-17) comparable with those that inhibit the functions of Arf proteins in other systems. Succinylated Arf-1-(2-17) had a negligible effect on Ca2+ inflow. GTP[S] and Arf-1-(2-17) completely inhibited the synergistic action of GTP and Ins(1,4,5)P3 in releasing 45Ca2+ from rat liver microsomes loaded with 45Ca2+. AlF4(-) (under conditions expected to activate trimeric G-proteins) and succinylated Arf-1-(2-17) had no effect on GTP/Ins(1,4,5))3-induced 45Ca2+ release, and a mastoparan analogue caused partial inhibition. Arf-1-(2-17) did not inhibit 45Ca2+ release induced by either thapsigargin or ionomycin. It is concluded that a low-molecular-mass G protein, most probably a member of the Arf protein family, is required for store activated Ca2+ inflow in rat hepatocytes. The idea that the role of this G protein is to maintain a region of the SER in the correct intracellular location is discussed briefly. PMID- 9371705 TI - Bovine cytosolic IMP/GMP-specific 5'-nucleotidase: cloning and expression of active enzyme in Escherichia coli. AB - A cDNA coding for bovine cytosolic IMP/GMP-specific 5'-nucleotidase endowed with phosphotransferase activity was cloned from calf thymus RNA, by 5' and 3' rapid amplification of cDNA ends protocols (5' and 3' RACE). Two products were isolated: a 5' RACE 1.6 kb fragment and a 3' RACE 2.0 kb fragment, with an overlapping region of 505 bp, leading to a total length of approx. 2951 bp. The similarity in the coding region to that of the human 5'-nucleotidase cDNA sequence [Oka, Matsumoto, Hosokawa and Inoue (1994) Biochem. Biophys. Res. Commun. 205, 917-922], indirectly identified as a 5'-nucleotidase, was 94% and the deduced amino acid sequences were 99.5% identical. The bovine cDNA sequence included the sequences codifying for six peptides obtained from 5' nucleotidase/phosphotransferase purified from calf thymus. Northern blots of human mRNA species from different tissues showed a 3.6 kb mRNA expressed at equal levels in most tissues. The cDNA was cloned into a pET-28c expression vector and the protein obtained after induction had a molecular mass of 61 kDa under SDS/PAGE. It exhibited both 5'-nucleotidase and phosphotransferase activity, as well as immunological and kinetic properties similar to those of the enzyme purified from calf thymus. This is the first time that a fully active recombinant 5'nucleotidase has been described. PMID- 9371704 TI - Inhibition of Ca2+ release from Trypanosoma brucei acidocalcisomes by 3,5-dibutyl 4-hydroxytoluene: role of the Na+/H+ exchanger. AB - Acidocalcisomes are acidic vacuoles present in trypanosomatids that contain a considerable fraction of intracellular Ca2+. They possess a vacuolar-type H+ ATPase for H+ uptake, a Ca2+/H+ countertransporting ATPase for Ca2+ uptake and a Ca2+/nH+ antiporter for Ca2+ release. Trypanosoma brucei procyclic trypomastigotes acidocalcisomes possess, in addition, an Na+/H+ antiporter that may participate in Ca2+ release from these organelles. In this work we show that the hydrophobic antioxidant 3,5-dibutyl-4-hydroxy toluene (BHT), at concentrations in the range 1-20 microM, inhibits Na+-induced Ca2+ release from the acidocalcisomes of digitonin-permeabilized procyclic trypomastigotes in a concentration-dependent manner. This effect supports the notion that Ca2+ release from this compartment is regulated by the activity of the Na+/H+ antiporter. In the presence of BHT, Ca2+ release could still be obtained by nigericin-mediated alkalinization of the acidocalcisomes, clearly demonstrating that the action of BHT is not at the level of the Ca2+/nH+ antiporter but on that of the Na+/H+ antiporter. In the same range of concentrations and depending on the preincubation time, BHT had an stimulatory or an inhibitory effect on the vacuolar H+-ATPase present in T. brucei acidocalcisomes. Since these effects of BHT were obtained at concentrations which are commonly used for its antioxidant properties, these results indicate that care should be exercised when attributing effects of BHT to only these properties. PMID- 9371706 TI - Use of photoactivatable sphingolipid analogues to monitor lipid transport in mammalian cells. AB - Photoactivatable derivatives of ceramide, glucosylceramide (GlcCer) and sphingomyelin {3-(p-azido-m-[125I]iodophenyl)propionylceramide, 3-(p-azido-m [125I]iodophenyl)propionyl-GlcCer and 3-(p-azido-m [125I]iodophenyl)propionylsphingomyelin} were synthesized in an attempt to identify compartment-specific proteins involved in sphingolipid sorting or metabolism. In HT29 and BHK cells the ceramide analogue entered the cell by monomeric diffusion, as evidenced by the probe's efficient internalization at low temperature (4 degrees C). In contrast, the photoactivatable GlcCer was internalized only at elevated temperatures (37 degrees C), presumably reflecting an endocytic mechanism of uptake. The photoactivatable ceramide was mainly metabolized to the corresponding sphingomyelin analogue, but small amounts of GlcCer and galactosylceramide were also synthesized. The newly synthesized photoreactive sphingomyelin was subsequently transported to the cell surface, a process that was effectively inhibited by the presence of brefeldin A. The incubation of cells with photoactivatable analogues at 4 degrees C, followed by illumination, led to the association of sphingolipid with a specific subset of proteins. The protein labelling pattern of ceramide differed from that of glucosylceramide. A further shift in labelling pattern was apparent when the cells were incubated with the lipid analogues at 37 degrees C. Moreover, most of the proteins labelled by photoreactive sphingomyelin seemed to be detergent insoluble, which is indicative of a location in sphingolipid-rich microdomains at the plasma membrane. The potential of applying photoactivatable sphingolipids to further define and identify the role of distinct proteins in sphingolipid biosynthesis, transport and sorting, is discussed. PMID- 9371707 TI - Mechanisms of mitogen-activated protein kinase activation by nicotine in small cell lung carcinoma cells. AB - We have previously reported that nicotine stimulates cell proliferation of three small-cell lung carcinoma (SCLC) cell lines by activating nicotinic receptors of the neuronal type. Here we report that, in the GLC-8 SCLC cell line, nicotine stimulates mitogen-activated protein (MAP) kinase activity in a concentration- and time-dependent manner (ED50 = 10 nM). The nicotine effect was antagonized by mecamylamine, an antagonist specific for neuronal nicotinic receptors. The absence of extracellular Ca2+, or pretreatment with pertussis toxin or the tyrosine kinase inhibitor genistein inhibited the action of nicotine on MAP kinase. Moreover, supernatants from nicotine-stimulated cells transferred to cells pretreated with mecamylamine were still capable of activating MAP kinase. On the other hand, the same supernatants transferred to cells pretreated with mecamylamine and pertussis toxin or genistein failed to activate MAP kinase. These findings suggest that nicotine elicits its stimulatory effect on MAP kinase in SCLC cells indirectly by inducing the production and/or release of a factor which then acts via a pertussis toxin- and tyrosine kinase-sensitive route. PMID- 9371708 TI - Interaction of caldesmon with endoplasmic reticulum membrane: effects on the mobility of phospholipids in the membrane and on the phosphatidylserine base exchange reaction. AB - We have previously demonstrated by tryptophan fluorescence the interaction of caldesmon with anionic phospholipid vesicles [Czurylo, Zborowski and Dabrowska (1993) Biochem. J. 291, 403-408]. In the present work we investigated the interaction of caldesmon with natural-membrane (rat liver endoplasmic reticulum) phospholipids by co-sedimentation assay. The results indicate that 1 mol of caldesmon binds approx. 170 mol of membrane phospholipids with a binding affinity constant of 7.3 x 10(6) M-1. The caldesmon-membrane phospholipid complex dissociates with increasing salt concentration and in the presence of Ca2+/calmodulin. As indicated by EPR measurements of membrane lipids labelled with 5-doxyl stearate and TEMPO-phosphatidylethanolamine, binding of caldesmon results in an increase in mobility of the acyl chains (in the region of carbon 5) and a decrease in polar headgroup mobility of phospholipids. Interaction of caldesmon with phospholipids is accompanied by inhibition of phosphatidylethanolamine synthesis via a phospholipid base-exchange reaction, with phosphatidylserine as substrate. This shows that, of the endoplasmic reticulum membrane phospholipids, the main target of caldesmon is phosphatidylserine. PMID- 9371709 TI - Thrombin-induced translocation of GLUT3 glucose transporters in human platelets. AB - Platelets derive most of their energy from anaerobic glycolysis; during activation this requirement rises approx. 3-fold. To accommodate the high glucose flux, platelets express extremely high concentrations (155+/-18 pmol/mg of membrane protein) of the most active glucose transporter isoform, GLUT3. Thrombin, a potent platelet activator, was found to stimulate 2-deoxyglucose transport activity 3-5-fold within 10 min at 25 degrees C, with a half-time of 1 2 min. To determine the mechanism underlying the increase in glucose transport activity, an impermeant photolabel, [2-3H]2N-4-(1-azi-2,2,2-trifluoethyl)benzoyl 1,3, -bis-(d-mannose-4-ylozy)-2-propylamine, was used to covalently bind glucose transporters accessible to the extracellular milieu. In response to thrombin, the level of transporter labelling increased 2.7-fold with a half-time of 1-2 min. This suggests a translocation of GLUT3 transporters from an intracellular site to the plasma membrane in a manner analogous to that seen for the translocation of GLUT4 in insulin-stimulated rat adipose cells. To investigate whether a similar signalling pathway was involved in both systems, platelets and adipose cells were exposed to staurosporin and wortmannin, two inhibitors of GLUT4 translocation in adipose cells. Thrombin stimulation of glucose transport activity in platelets was more sensitive to staurosporin inhibition than was insulin-stimulated transport activity in adipose cells, but it was totally insensitive to wortmannin. This indicates that the GLUT3 translocation in platelets is mediated by a protein kinase C not by a phosphatidylinositol 3-kinase mechanism. In support of this contention, the phorbol ester PMA, which specifically activates protein kinase C, fully stimulated glucose transport activity in platelets and was equally sensitive to inhibition by staurosporin. This study provides a cellular mechanism by which platelets enhance their capacity to import glucose to fulfil the increased energy demands associated with activation. PMID- 9371710 TI - Formation of the NO donors glyceryl mononitrate and glyceryl mononitrite from the reaction of peroxynitrite with glycerol. AB - Peroxynitrite (ONOO-), formed from the rapid reaction of superoxide (O2-.) with NO, is known to generate stable compounds capable of donating NO on reaction with thiols and molecules containing hydroxy groups. Using glycerol as a model compound for the reactions of ONOO- with biomolecules containing hydroxy groups, we separated the products and identified them by HPLC/MS. It was shown that both glyceryl mononitrate and glyceryl mononitrite were formed and released NO on incubation with copper and l-cysteine. The compounds were stable over a period of 4h when shielded from light and kept on ice. Slow spontaneous decomposition occurred in the buffer used for the bioassay, but this was not sufficient to explain the vasorelaxing properties of these NO donors. It is concluded that the stable organic nitrate and nitrite have the capacity to be metabolized by vascular tissues, resulting in vasorelaxation. PMID- 9371711 TI - Intracellular calcium release is more efficient than calcium influx in stimulating mitochondrial NAD(P)H formation in adrenal glomerulosa cells. AB - We compared the effect on mitochondrial NAD(P)H formation of calcium release from intracellular stores with that of calcium influx from the extracellular space. Simultaneous measurements of cytoplasmic free calcium ion concentration and mitochondrial NAD(P)H were performed on fura-PE3-loaded single rat adrenal glomerulosa cells. The effects of equipotent stimuli in terms of the evoked Ca2+ response were compared. Angiotensin II (AII; 1 nM) induced a higher amplitude NAD(P)H response than K+ (5.6-7.6 mM). Vasopressin (1 microM) also induced a greater initial NAD(P)H formation than K+, although the Ca2+ signal evoked by the two agonists had similar amplitude. To examine the effect of Ca2+ release from internal stores we applied AII in Ca2+-free medium. We compared the effect on NAD(P)H formation of Ca2+ release with Ca2+ influx induced by K+, and with capacitative Ca2+ influx induced by AII. NAD(P)H formation in response to Ca2+ release was greater than that induced by Ca2+ influx, irrespective of whether induced by K+ or AII. Our results indicate that Ca2+, presumably released in the vicinity of mitochondria, activates mitochondrial dehydrogenases more efficiently than Ca2+ entering through the plasma membrane. These data confirm the biological significance of previous observations showing that Ca2+ released from inositol 1,4, 5-trisphosphate-sensitive internal stores increases mitochondrial matrix [Ca2+] to a greater extent than extracellular Ca2+. PMID- 9371712 TI - The two phenylalanines in the GFFKR motif of the integrin alpha6A subunit are essential for heterodimerization. AB - The membrane-proximal domain of the integrin alpha subunit contains a conserved motif of five amino acid residues, GFFKR. We deleted this motif from the human alpha6A subunit and found that in COS-7 cells this mutant cannot associate with the beta1 subunit and is retained in the endoplasmic reticulum. Point mutations in the GFFKR motif of the glycine residue or the two highly charged amino acids, or deletion of the lysine and arginine residues, had no effect on the ability of alpha6 to interact with beta1 and to be expressed at the cell surface. In contrast, by replacing either of the two phenylalanines with alanine, or by deletion of both of these residues, alpha6 was incapable of associating with beta1. The alpha6 point mutants that associated with beta1 were expressed in K562 cells and their responsiveness to integrin-activating factors was determined. None of these transfectants bound spontaneously to laminin-1, but binding could be induced by either PMA or the stimulating anti-beta1 antibody TS2/16 to the same extent as that of the wild-type transfectant. The ability of these mutants to initiate focal-contact formation in CHO cells plated on laminin-1 substrates also appeared to be unaltered. Thus the behaviour of alpha6 mutants involving the glycine, lysine or arginine residues was indistinguishable from that of wild-type alpha6 both in inside-out and outside-in signalling. In contrast, deletion of the cytoplasmic domain of alpha6 C-terminal of the GFFKR motif resulted in a loss of responsiveness of alpha6beta1 to PMA stimulation and formation of focal contacts on laminin-1. However, this mutant was targeted to focal contacts formed by other integrins, even when they had not bound ligand. Together, these results suggest that the two phenylalanine residues of the GFFKR motif provide a site for interaction of the alpha6A subunit with beta1, whereas the cytoplasmic domain C terminal of this motif is involved in the regulation of bidirectional signalling via alpha6Abeta1. PMID- 9371713 TI - Characterization of five different proteins produced by alternatively spliced mRNAs from the human cAMP-specific phosphodiesterase PDE4D gene. AB - We have isolated and characterized complete cDNAs for two isoforms (HSPDE4D4 and HSPDE4A5) encoded by the human PDE4D gene, one of four genes that encode cAMP specific rolipram-inhibited 3',5'-cyclic nucleotide phosphodiesterases (type IVPDEs; PDE4 family). The HSPDE4D4 and HSPDE4D5 cDNAs encode proteins of 810 and 746 amino acids respectively. A comparison of the nucleotide sequences of these two cDNAs with those encoding the three other human PDE4D proteins (HSPDE4D1, HSPDE4D2 and HSPDE4D3) demonstrates that each corresponding mRNA transcript has a unique region of sequence at or near its 5'-end, consistent with alternative mRNA splicing. Transient expression of the five cDNAs in monkey COS-7 cells produced proteins of apparent molecular mass under denaturing conditions of 68, 68, 95, 119 and 105 kDa for isoforms HSPDE4D1-5 respectively. Immunoblotting of human cell lines and rat brain demonstrated the presence of species that co-migrated with the proteins produced in COS-7 cells. COS-cell-expressed and native HSPDE4D1 and HSPDE4D2 were found to exist only in the cytosol, whereas HSPDE4D3, HSPDE4D4 and HSPDE4D5 were found in both cytosolic and particulate fractions. The IC50 values for the selective PDE4 inhibitor rolipram for the cytosolic forms of the five enzymes were similar (0.05-0.14 microM), whereas they were 2-7-fold higher for the particulate forms of HSPDE4D3 and HSPDE4D5 (0.32 and 0.59 microM respectively), than for the corresponding cytosolic forms. Our data indicate that the N-terminal regions of the HSPDE4D3, HSPDE4D4 and HSPDE4D5 proteins, which are derived from alternatively spliced regions of their mRNAs, are important in determining their subcellular localization, activity and differential sensitivity to inhibitors. PMID- 9371714 TI - Molecular cloning and transient expression in COS7 cells of a novel human PDE4B cAMP-specific phosphodiesterase, HSPDE4B3. AB - 5'-Rapid amplification of cDNA ends, done on poly(A)+ RNA from human U87 cells, was used to identify 420 bp of novel 5' sequence of a PDE4B cAMP-specific phosphodiesterase (PDE). This identified an open reading frame encoding a putative 721-residue 'long-form' PDE4B splice variant, which we term HSPDE4B3. HSPDE4B3 differs from the two known PDE4B forms by virtue of its unique 79 residue N-terminal region, compared with the unique N-terminal regions of 94 and 39 residues found in HSPDE4B1 and HSPDE4B2 respectively. In transfected COS7 cells the two long forms, HSPDE4B1 and HSPDE4B3, had molecular masses of approx. 104 and approx. 103 kDa respectively. Expressed in COS-7 cells, the three HSPDE4B isoforms were found in the high-speed supernatant (cytosol) fraction as well as both the high-speed pellet (P2) and low-speed pellet (P1) fractions. All isoforms showed similar Km values for cAMP hydrolysis (1.5-2.6 microM). The maximal activities of the soluble cytosolic activity of the two long forms were very similar, whereas that of the short form, HSPDE4B2, was approx. 4-fold higher. Particulate-associated HSPDE4B1 and HSPDE4B2 were less active (approx. 40%) than their cytosol forms, whereas particulate HSPDE4B3 was similar in activity to its cytosolic form. Particulate and cytosolic forms of HSPDE4B1 and HSPDE4B3 were similarly inhibited by rolipram {4-[3-(cyclopentoxyl)-4-methoxyphenyl]-2 pyrrolidone}, the selective inhibitor of PDE4 (IC50 0.05-0.1 microM), whereas particulate-associated HSPDE4B2 was profoundly (approx. 10-fold) more sensitive (IC50 0.02 microM) to rolipram inhibition than its cytosolic form (IC50 0.2 microM). The various particulate-associated HSPDE4B isoforms showed very different susceptibilities to solubilization with the detergent Triton X-100 and high NaCl concentration. A novel cDNA, called pRPDE74, was obtained by screening a rat olfactory lobe cDNA library. This contained an open reading frame encoding a 721-residue protein that showed approx. 96% amino acid identity with HSPDE4B3 and is proposed to reflect the rat homologue of this human enzyme and is thus called RNPDE4B3. Alternative splicing of mRNA generated from both the human and rat PDE4B genes produces long and short splice variants that have unique N terminal splice regions. It is suggested that these alternatively spliced regions determine changes in the maximal catalytic activity of the isoforms, their susceptibility to inhibition by rolipram and mode of interaction with particulate fractions. PMID- 9371715 TI - A newly synthesized molecule derived from ruthenium cation, with antitumour activity, activates NADPH oxidase in human neutrophils. AB - To determine the nature of the mechanism by which certain derived ruthenium (Ru) complexes induce regression in tumour growth, we have investigated the possibility that this mechanism was associated with an increase of superoxide anion (O2-. production by phagocytic cells, which are usually found in tumour nodes. Here we present evidence that a newly synthesized complex, Ru3+-propylene 1, 2-diaminotetra-acetic acid (Ru-PDTA), derived from Ru and the sequestering ligand (PDTA), specifically stimulates O2-. production. This increase was associated with the translocation of cytosolic factors p47(phox) and p67(phox) of NADPH oxidase to the plasma membrane. The Ru-PDTA-complex-dependent O2-. production was abrogated by staurosporine, partially inhibited by diphenylene iodonium, and it was insensitive to pertussis toxin or dibutyryl cyclic AMP pretreatment. An increase of cytosolic Ca2+ levels were also detected in neutrophils treated with the Ru-PDTA complex. Also, Ru-PDTA complex induced the phosphorylation of tyrosine residues of several proteins as assessed by Western blotting. Present data are consistent with the possibility that Ru-PDTA-dependent antitumour effects are due in part to the complex's ability to stimulate the release of toxic oxygen metabolites from phagocytic cells infiltrating tumour masses. PMID- 9371717 TI - Agonist-specific behaviour of the intracellular Ca2+ response in rat hepatocytes. AB - A variety of agonists stimulate in hepatocytes a response that takes the shape of repetitive cytosolic free Ca2+ transients called Ca2+ oscillations. The shape of spikes and the pattern of oscillations in a given cell differ depending on the agonist of the phosphoinositide pathway that is applied. In this study, the response of individual rat hepatocytes to maximal stimulation by arginine vasopressin (AVP), phenylephrine and ADP was investigated by fluorescence microscopy and flash photolysis. Hepatocytes loaded with Ca2+-sensitive probes were stimulated with a first agonist to evoke a maximal response, and then a second agonist was added. When phenylephrine or ADP was used as the first agonist, AVP applied subsequently could elicit an additional response, which did not happen when AVP was first applied and phenylephrine or ADP was applied later. Cells microinjected with caged myo-inositol 1,4,5-trisphosphate (IP3) were challenged with the different agonists and, when a maximal response was obtained, photorelease of IP3 was triggered. Cells maximally stimulated with AVP did not respond to IP3 photorelease, whereas those stimulated with phenylephrine or ADP responded with a fast Ca2+ spike above the elevated steady-state level, which was followed by an undershoot. In contrast, with all three agonists, IP3 photorelease triggered at the top of an oscillatory Ca2+ transient was able to mobilize additional Ca2+. These experiments indicate that the differential response of cells to agonists is found not only during Ca2+ oscillations but also during maximal agonist stimulation and that potency and efficacy differences exist among agonists. PMID- 9371716 TI - Detection of free radicals produced from the reaction of cytochrome P-450 with linoleic acid hydroperoxide. AB - The ESR spin-trapping technique was employed to investigate the reaction of rabbit cytochrome P-450 1A2 (P450) with linoleic acid hydroperoxide. This system was compared with chemical systems where FeSO4 or FeCl3 was used in place of P450. The spin trap 5, 5'-dimethyl-1-pyrroline N-oxide (DMPO) was employed to detect and identify radical species. The DMPO adducts of hydroxyl, O2-., peroxyl, methyl and acyl radicals were detected in the P450 system. The reaction did not require NADPH-cytochrome P-450 reductase or NADPH. The same DMPO-radical adducts were detected in the FeSO4 system. Only DMPO-.OH radical adduct and carbon centred radical adducts were detected in the FeCl3 system. Peroxyl radical production was completely O2-dependent. We propose that polyunsaturated fatty acids are initially reduced to form alkoxyl radicals, which then undergo intramolecular rearrangement to form epoxyalkyl radicals. Each epoxyalkyl radical reacts with O2, forming a peroxyl radical. Subsequent unimolecular decomposition of this peroxyl radical eliminates O2-. radical. PMID- 9371718 TI - A novel type of thermostable alpha-D-glucosidase from Thermoanaerobacter thermohydrosulfuricus exhibiting maltodextrinohydrolase activity. AB - An alpha-glucosidase with the ability to attack polymeric substrates was purified to homogeneity from culture supernatants of Thermoanaerobacter thermohydrosulfuricus DSM 567. The enzyme is apparently a glycoprotein with a molecular mass of 160 kDa. Maximal activity is observed between pH5 and 7 at 75 degrees C. The alpha-glucosidase is active towards p-nitrophenyl-alpha-D glucoside, maltose, malto-oligosaccharides, starch and pullulan. Highest activity is displayed towards the disaccharide maltose. In addition to glucose, maltohexaose and maltoheptaose can be detected as the initial products of starch hydrolysis. After short incubations of pullulan, glucose is found as the only product. At high substrate concentrations, maltose and malto-oligosaccharide, but not glucose, are used as acceptors for glucosyl-transfer. These findings indicate that the T. thermohydrosulfuricus enzyme represents a novel type of alpha glucosidase exhibiting maltase, glucohydrolase and 'maltodextrinohydrolase' activity. PMID- 9371719 TI - Cleavage of arginyl-arginine and lysyl-arginine from the C-terminus of pro hormone peptides by human germinal angiotensin I-converting enzyme (ACE) and the C-domain of human somatic ACE. AB - Mammalian germinal angiotensin I-converting enzyme (gACE) is a single-domain dipeptidyl carboxypeptidase found exclusively in male germ cells, which has almost identical sequence and enzymic properties with the C-domain of the two domain somatic ACE. Mutant mice that do not express gACE are infertile, suggesting a role for the enzyme in the processing of undefined peptides involved in fertilization. A number of spermatid peptides [e.g. cholecystokinin (CCK) and gastrin] are processed from pro-hormones by endo- and exo-proteolytic cleavages which might generate substrates for gACE. We have shown that peptide hormone intermediates with Lys/Arg-Arg at the C-terminus are high-affinity substrates for human gACE. gACE from human sperm cleaved Arg-Arg from the C-terminus of the CCK5 GRR (GWMDFGRR), a peptide corresponding to the C-terminus of a CCK-gastrin prohormone intermediate. Hydrolysis of CCK5-GRR by recombinant human C-domain ACE was Cl- dependent, with maximal activity achieved in 5-10 mM NaCl at pH 6.4. C Domain ACE cleaved Lys/Arg-Arg from the C-terminus of dynorphin-(1-7), a pro-TRH peptide KRQHPGKR, and two insect peptides FSPRLGKR and FSPRLGRR. C-Domain ACE displayed high affinity towards all these substrates with Vmax/Km values between 14 and 113 times greater than the Vmax/Km for the conversion of the best known ACE substrate, angiotensin I, into angiotensin II. In conclusion, we have identified a new class of substrates for human gACE, and we suggest that gACE might be an alternative to carboxypeptidase E for the trimming of basic dipeptides from the C-terminus of intermediates generated from pro-hormones by subtilisin-like convertases in human male germ cells. PMID- 9371720 TI - Differential control of murine aldose reductase and fibroblast growth factor (FGF)-regulated-1 gene expression in NIH 3T3 cells by FGF-1 treatment and hyperosmotic stress. AB - Aldose reductase (AR) is an NADPH-dependent aldo-keto reductase implicated in cellular osmoregulation and detoxification. Two distinct murine genes have been identified that are predicted to encode proteins with significant amino acid sequence identity with mouse AR: mouse vas deferens protein and fibroblast growth factor (FGF)-regulated-1 protein (FR-1). Here we report that the AR and FR-1 genes are differentially regulated in NIH 3T3 fibroblasts. FGF-1 stimulation of quiescent cells induces both AR and FR-1 mRNA levels, but the effect on FR-1 mRNA expression is significantly greater. FGF-1 treatment also increases FR-1 protein expression, as determined by Western-blot analysis using FR-1-specific polyclonal antiserum. Calf serum stimulation of quiescent cells increases AR mRNA expression but not FR-1 mRNA expression. Finally, when NIH 3T3 cells are grown in hypertonic medium, AR mRNA levels are significantly increased whereas FR-1 mRNA levels are only slightly up-regulated. These results indicate that the AR and FR-1 genes are differentially regulated in murine fibroblasts by two different growth-promoting agents and by hyperosmotic stress. Therefore these structurally related enzymes may have at least some distinct cellular functions; for example, although both AR and FR-1 activity may be important for the metabolic changes associated with cellular proliferation, AR may be the primary aldo-keto reductase involved in cellular osmoregulation. PMID- 9371721 TI - Glycation-induced inactivation and loss of antigenicity of catalase and superoxide dismutase. AB - Oxidative mechanisms are thought to have a major role in several biological phenomena, including cataract formation and diabetic complications. Here we investigate the inactivation of catalase and superoxide dismutase, both powerful antioxidant enzymes, by sugars of different glycating abilities, and the loss of antigenicity that was monitored by the loss of activity after immunoprecipitation with monospecific antibodies. The antigenicity of non-glycated or glycated enzymes separated by affinity chromatography were determined by dot-blotting. Incubation with sugars resulted in a time-dependent inactivation of the enzymes. Ribose and fructose inactivated them more rapidly than glucose and glucose 6 phosphate. Glycation induced losses of antigenicity and inactivation simultaneously. The glycated enzymes had entirely lost their antigenicity compared with non-glycated enzyme. These results further support the idea that inactivation of enzyme and loss of antigenicity are simultaneous. This might occur in the pathogenesis of diabetic complications and aging. PMID- 9371722 TI - Trans-regulation of myogenin promoter/enhancer activity by c-ski during skeletal muscle differentiation: the C-terminus of the c-Ski protein is essential for transcriptional regulatory activity in myotubes. AB - c-ski gene product is a nuclear protein with myogenesis-promoting and transforming activities. We have analysed the effects of c-ski transfection on the promoter/enhancer activity of the upstream region of the myogenin gene during in vitro myogenesis using CAT reporter assay. When co-transfected with c-ski into myogenic C2C12 cells, promoter/enhancer activity was efficiently suppressed in proliferating cells, but the myogenesis-induced increase in activity was potentiated approximately ten times more (150-fold in the ski-transfected cells) than the ordinary increase (12-fold in the mock) 48 h after induction of differentiation. In non-myogenic 10T1/2 cells, c-ski transfection caused persistent suppression of promoter/enhancer activity in both proliferating and growth-arrested (i.e. myogenesis-inducing) conditions. Thus the ski-dependent potentiation of myogenin gene transcriptional activity appears to be specific for myogenesis. The C-terminal region (amino acids 595-663) of the c-Ski protein was essential for the potentiating activity in myotubes. Other members of the ski gene family, snoN and snoA, were ineffective in transactivation, possibly because of the defect in the corresponding C-terminal region. c-Ski protein underwent a mobility shift on SDS/PAGE after in vitro myogenesis which may explain the conversion of the activity from suppressive in myoblasts to potentiating in myotubes. Deletion analysis of the upstream region of the myogenin gene revealed that a responsive element to c-ski in myotubes is located at a distinct site upstream of the basal promoter/enhancer region. PMID- 9371723 TI - Endogenous production of tumour necrosis factor is required for manganese superoxide dismutase expression by irradiation in the human monocytic cell line THP-1. AB - Manganese superoxide dismutase (MnSOD) is a mitochondrial enzyme that scavenges superoxide (O2-) ions. We studied the regulation of MnSOD gene expression by irradiation and the mechanisms in human monocytic cell line THP-1. We found that irradiation induced expression of the MnSOD gene through the autocrine mechanism, involving the production of tumour necrosis factor (TNF). Irradiation increased TNF production in THP-1 cells, and TNF increased the levels of MnSOD transcripts. Supernatant from irradiated THP-1 cells induced the expression of MnSOD mRNA, and anti-TNF antibody blocked the induction of MnSOD mRNA. Irradiation also increased the levels of MnSOD mRNA in other myelocytic cell lines, HL60 and KG-1, and the ovarian cancer cell line SK-OV-3. Moreover, increased levels of MnSOD mRNA were observed in mature myeloid cells, including macrophages and granulocytes, as well as in immature cells. However, irradiation did not increase the level of MnSOD mRNA in THP-1 cells with prolonged exposure to PMA. We also found that irradiation increased the rate of MnSOD transcription, and irradiation stabilized MnSOD mRNA in THP-1 cells. Our results indicate that the endogenous production of TNF is required, at least in part, for the induction of MnSOD mRNA expression by irradiation in THP-1 cells, and the increased levels of MnSOD transcripts on irradiation occur through a pathway involving protein kinase C activation. Our results also indicate that the increase in MnSOD mRNA caused by irradiation is regulated by both transcriptional and post-transcriptional mechanisms. PMID- 9371725 TI - Formation of one or more intrachain disulphide bonds is required for the intracellular processing and transport of CD36. AB - In monocytes/macrophages, CD36 is thought to have a role as a scavenger receptor, mediating the phagocytosis of apoptotic cells and the endocytic uptake of oxidized low-density lipoproteins and fatty acids. The proposed topology of CD36 predicts that, of ten cysteine residues, six lie in the extracellular domain, whereas four are equally distributed in the two short terminal tails flanking the N-terminal and C-terminal hydrophobic stretches. Here we investigate the formation of intrachain disulphide bonds, on the basis of the assumption that the cysteine residues present in the luminal domains are generally oxidized, whereas those in the cytosol are reduced. As revealed by gel mobility-shift assays, disulphide bonds are present in the extracellular domain of the CD36 molecule. The formation of these bonds is required for the transport of CD36 from endoplasmic reticulum to Golgi. Furthermore reactive thiol groups are present in the CD36 sequence, which upon lysis form an intrachain extra loop as an artifact. This disulphide bond is not formed in either (1) truncated CD36 lacking the two C terminal cysteine residues or (2) Triton X-100-insoluble wild-type CD36 molecules, suggesting that, in this fraction, the C-terminal thiol groups are modified. PMID- 9371726 TI - Formation and properties of dimeric recombinant horseradish peroxidase in a system of reversed micelles. AB - Wild-type recombinant horseradish peroxidase purified and refolded from Escherichia coli inclusion bodies has been studied in the system of bis(2 ethylhexyl)sulphosuccinate sodium salt (Aerosol OT)-reversed micelles in octane. In contrast with native horseradish peroxidase the wild-type recombinant enzyme forms dimeric structures as judged by sedimentation analysis. Peroxidase substrates affect the equilibrium between monomeric and dimeric enzyme forms. The dependence of the catalytic activity of recombinant peroxidase on the degree of hydration of the surfactant exhibits two maxima with pyrogallol, o-phenylene- diamine, guaiacol and o-dianisidine, with different ratios of activities for the first and second maxima. The differences in activities of monomeric and dimeric forms of the recombinant horseradish peroxidase provide evidence for active-site screening in dimeric forms. This has been used to model a dimeric structure of recombinant horseradish peroxidase with the screened entrance to the active site. In the model structure obtained, three of eight glycosylation sites were screened. This might explain the absence of dimeric structures in native enzyme peroxidase. The system of reversed micelles provides, for the first time, evidence for the formation of dimeric structures by recombinant plant peroxidase with an altered substrate specificity compared with the native enzyme. Thus one can assume that haem-containing peroxidases in general are able to form dimeric structures. PMID- 9371724 TI - Phosphorylation of complement component C3 after synthesis in U937 cells by a putative protein kinase, casein kinase 2, which is regulated by CD11b: evidence that membrane-bound proteases preferentially cleave phosphorylated C3. AB - It was our aim in this study to investigate the possibility that the third component of complement (C3) is phosphorylated during synthesis and secretion in U937 cells. Labelling of U937 cells with [32P]Pi, followed by immunoprecipitation of C3 from cell lysates and culture supernatants at different time points, showed that C3 was phosphorylated intracellularly immediately before release into the medium, which initiated cleavage of the protein into an iC3b-like fragment. Stimulation of CD11b/CD18 increased phosphorylation 7-fold, from a basal level of 2%. The phosphorylation sites in C3 did not resemble those described previously for casein kinase (CK) 1, cAMP-dependent protein kinase A or calcium- and phospholipid-dependent protein kinase C. Instead, protein kinase CK2 was suggested inasmuch as: (1) CK2 was detected both on the cell surface and on shed microparticles; (2) phosphorylation of purified C3 by microparticles was abolished by a monoclonal antibody, anti-CK2; (3) the [32P]Pi tag of both phosphorylated C3 (secreted from U937 cells) and of microparticle-phosphorylated C3, which was cleaved either by membrane proteases or by leucocyte elastase, was found in a 40 and a 70 kDa polypeptide; (4) both secreted C3 and C3 phosphorylated in vitro were much more susceptible to cleavage by proteases. Generation of C3 fragments provides a means by which U937 cells can stimulate nearby cells which are expressing complement receptors. The present study demonstrates that the cleavage of C3 is controlled by an intracellular phosphorylation event regulated by CD11b/CD18. PMID- 9371727 TI - Distinctive regulation of v-Src-associated phosphatidylinositol 3-kinase during PC12 cell differentiation. AB - In chicken embryo fibroblasts, the binding of v-Src to PtdIns 3-kinase requires Src homology domains, SH3, SH2 and the SH1 or kinase domain, which induces the cytoskeletal disruption associated with fibroblast transformation. In the rat phaeochromocytoma PC12 cell line, v-Src has a different effect on the cytoskeleton, inducing neurite extension rather than cytoskeletal disruption. Here we show that v-Src-induced neurite outgrowth is suppressed by the selective PtdIns 3-kinase inhibitor LY294002, suggesting that this effect of v-Src in PC12 cells also requires the activity of the lipid kinase. However, in contrast with chicken embryo fibroblasts, the association of PtdIns 3-kinase with v-Src in PC12 cells is delayed until several hours after activating the v-Src tyrosine kinase. Furthermore the v-Src-associated p85 regulatory subunit of PtdIns 3-kinase is not phosphorylated on tyrosine in PC12 cells and associates only weakly with isolated v-Src homology domains (SH3/SH2) in a Src kinase-independent manner. However, p85 and v-Src both associate with an unidentified protein (of molecular mass approx. 68 kDa; termed p68), which becomes tyrosine phosphorylated concomitantly with the association of both p85 and PtdIns 3-kinase with v-Src in PC12 cells. Thus we conclude that the mode of regulation of v-Src-associated PtdIns 3-kinase is cell context-dependent and that p68 might act as an adaptor protein to mediate the association of p85 and v-Src in PC12 cells. The different regulation of PtdIns 3 kinase in PC12 and in chicken embryo fibroblasts in response to v-Src activity might reflect the different cytoskeletal rearrangements induced by this oncoprotein in the two cell types. PMID- 9371728 TI - Cloning, functional expression and dietary regulation of the mouse neutral and basic amino acid transporter (NBAT). AB - The Na+-independent dibasic and neutral amino acid transporter NBAT is among the least hydrophobic of mammalian amino acid transporters. The transporter contains one to four transmembrane domains and induces amino acid transport activity via a b0,+-like system when expressed in Xenopus oocytes. However, the physiological role of NBAT remains unclear. Complementary DNA clones encoding mouse NBAT have now been isolated. The expression of mouse NBAT in Xenopus oocytes also induced an obligatory amino acid exchange activity similar to that of the b0,+-like system. The amount of NBAT mRNA in mouse kidney increased during postnatal development, consistent with the increase in renal cystine and dibasic transport activity. Dietary aspartate induced a marked increase in cystine transport via the b0,+ system in mouse ileum. A high-aspartate diet also increased the amount of NBAT mRNA in mouse ileum. In the ileum of mice fed on the aspartate diet, the extent of cystine transport was further increased by preloading brush border membrane vesicles with lysine. Hybrid depletion of NBAT mRNA from ileal polyadenylated RNA revealed that the increase in cystine transport activity induced by the high-aspartate diet, as measured in Xenopus oocytes, was attributable to NBAT. These results demonstrate that mouse NBAT has an important role in cystine transport. PMID- 9371729 TI - Oligomeric forms of the 148 kDa cartilage matrix protein. AB - The 148 kDa cartilage matrix protein (CMP), composed of three disulphide-bonded subunits, is a cartilage-specific glycoprotein found in association with fibrils of type II collagen and possibly with aggrecan. It is probable that CMP serves a structural role. As cartilage ages, an increasing proportion of the CMP becomes insoluble and resistant to extraction. In the present study, the isolation of CMP has been improved by inclusion of a hydrophobic chromatography step, thereby removing the remaining traces of collagen and proteoglycan. Evidence of self association of CMP is presented. Higher-molecular-mass forms of CMP, ranging in apparent molecular mass from 270 to 510 kDa and separated by SDS/PAGE, were located using a specific anti-CMP monoclonal antibody. Both CMP and its oligomeric forms are reducible to 52 kDa subunits, and only trace amounts of other proteins. The formation of oligomers, which may constitute 23% of the total cartilage matrix protein, could occur as a byproduct of the normal biosynthetic trimerization of subunits. Alternatively, the oligomers may represent a step toward the age-related cross-linking and insolubilization of CMP. PMID- 9371731 TI - Molecular cloning, characterization and localization of PfPK4, an eIF-2alpha kinase-related enzyme from the malarial parasite Plasmodium falciparum. AB - PfPK4, a protein kinase gene from the human malarial parasite Plasmodium falciparum, has been cloned utilizing oligonucleotide probing. The gene encodes a protein of a predicted length of 1123 amino acids, and within this amino acid sequence all the conserved regions characteristic of protein kinases can be identified. The catalytic kinase domain possesses highest identities (34-37%) with eukaryotic initiation factor-2alpha (eIF-2alpha) kinases, especially haem regulated inhibitory (HRI) protein kinases. There are two kinase inserts in PfPK4, located at positions common to eIF-2alpha kinases. The first insert separates kinase subdomains IV and VI by 559 amino acids, and the second subdomains VII and VIII by 41 amino acids. Both inserts are larger than their homologues in eIF-2alpha kinases. The sequence of PfPK4 has one putative haemin binding site. The recombinant protein, expressed in Escherichia coli, phosphorylates a synthetic peptide representing a substrate of eIF-2alpha kinases. Autophosphorylation and substrate phosphorylation are inhibited by haemin. Thus PfPK4 appears to be the first protozoan protein kinase related to eIF-2alpha kinases and might be the first non-mammalian HRI kinase. Western blots indicated that the protein is expressed as major forms of 80 and 90 kDa. Whereas the 80 kDa form is present throughout the intraerythrocytic development and in merozoites, the two 90 kDa forms are only found in mature parasites. One of the latter is also present in the membrane fraction of erythrocytes harbouring segmenters. Confocal microscopy detected the protein distributed throughout the trophozoite, whereas it was found in discrete foci (punctate distribution) in segmenters. PfPK4 co-localizes with P. falciparum 83 kDa antigen/apical membrane antigen-1 at the apical complex in segmenters and merozoites, but does not co localize with rhoptry-associated protein-1. PMID- 9371730 TI - Glycosyl-phosphatidylinositol anchor attachment in a yeast in vitro system. AB - The yeast mating pheromone precursor prepro-alpha factor was fused to C-terminal signals for glycosyl-phosphatidylinositol (GPI) anchor attachment, based on the sequence of the Saccharomyces cerevisiae protein Gas1p. Maturation of fusion proteins expressed in vivo required the presence of both a functional GPI attachment site and the synthesis of GPI precursors. Constructs were translated in vitro for use in cell-free studies of glycolipid attachment. The radiolabelled polypeptides were post-translationally translocated into yeast microsomes, where at least one third of the molecules received a GPI anchor. This approach offers distinct advantages over anchor attachment reactions that require co translational translocation of secretory peptide substrates. PMID- 9371733 TI - N-Acetyl-beta-D-glucopyranosylamine 6-phosphate is a specific inhibitor of glycogen-bound protein phosphatase 1. AB - Previous work has shown that the C-1-substituted glucose-analogue N-acetyl-beta-D glucopyranosylamine (1-GlcNAc) is a competitive inhibitor of glycogen phosphorylase (GP) and stimulates the inactivation of this enzyme by GP phosphatase. In addition to its effects on GP, 1-GlcNAc also prevents the glucose led activation of glycogen synthase (GS) in whole hepatocytes. Such an effect on GS was thought to be due to the formation of 1-GlcNAc-6-P by the action of glucokinase within the hepatocyte [Board, Bollen, Stalmans, Kim, Fleet and Johnson (1995) Biochem. J. 311, 845-852]. To investigate this possibility further, a pure preparation of 1-GlcNAc-6-P was synthesized. The effects of the phosphorylated glucose analogue on the activity of protein phosphatase 1 (PP1), the enzyme responsible for dephosphorylation and activation of GS, are reported. During the present study, 1-GlcNAc-6-P inhibited the activity of the glycogen bound form of PP1, affecting both the GSb phosphatase and GPa phosphatase activities. A level of 50% inhibition of GSb phosphatase activity was achieved with 85 microM 1-GlcNAc-6-P in the absence of Glc-6-P and with 135 microM in the presence of 10 mM Glc-6-P. At either Glc-6-P concentration, 500 microM 1-GlcNAc-6 P completely inhibited activity. The Glc-6-P stimulation of the GPa phosphatase activity of PP1 was negated by 1-GlcNAc-6-P but there was no inhibition of the basal rate in the absence of Glc-6-P. 1-GlcNAc-6-P inhibition was specific for the glycogen-bound form of PP1 and did not inhibit the GSb phosphatase activity of the cytosolic form of the enzyme. The present work explains our previous observations on the inactivating effects on GS of incubating whole hepatocytes with 1-GlcNAc. These observations have their basis in the inhibition of glycogen bound PP1 by 1-GlcNAc-6-P. A novel inhibitor of PP1, specific for the glycogen bound form of the enzyme, is presented. PMID- 9371732 TI - Bradykinin stimulates cAMP synthesis via mitogen-activated protein kinase dependent regulation of cytosolic phospholipase A2 and prostaglandin E2 release in airway smooth muscle. AB - Bradykinin stimulates cAMP synthesis in cultured airway smooth muscle (ASM) cells. This occurs via a pathway that involves: (1) the protein kinase C (PKC) dependent activation of mitogen-activated protein kinase (MAPK); (2) the MAPK dependent phosphorylation and activation of cytosolic phospholipase A2 (cPLA2) and (3) the utilization of cPLA2-derived arachidonate by the cyclo-oxygenase pathway to produce prostaglandin E2 (PGE2). PGE2 is released and binds to cell surface receptors to stimulate intracellular cAMP synthesis. The signalling pathway was confirmed by the use of PD098059 [the inhibitor of MAPK kinase-1 (MEK 1) activation], AACOCF3 (an inhibitor of cPLA2) and indomethacin (an inhibitor of cyclo-oxygenase), which all reduced bradykinin-stimulated cAMP synthesis. Bradykinin also elicits the inhibition of approx. 60% of the total cAMP phosphodiesterase activity in the cell [Stevens, Pyne, Grady and Pyne (1994) Biochem. J. 297, 233-239]. This is likely to decrease the rate of cAMP degradation markedly and therefore to potentiate PGE2-stimulated cAMP synthesis. Acute treatment of ASM cells with PMA (a direct activator of PKC) also stimulated the MAPK-dependent phosphorylation of cPLA2. However, in contrast with bradykinin, PMA did not stimulate arachidonate release, suggesting that additional signals (e.g. Ca2+ ions) are required for phosphorylation by MAPK to activate cPLA2. PMA was also without effect on PGE2 release and cAMP synthesis. Evidence that PKC can also directly regulate adenylate cyclase was obtained by using cells pretreated with cholera toxin. Under these conditions, PMA stimulated cAMP synthesis independently of arachidonate metabolites. Furthermore the combined treatment of cells with PMA (to activate PKC) and PGE2 (to activate Gs) stimulated synergistic cAMP synthesis. This might be due to the presence of the type 2 adenylate cyclase, which is synergistically activated by Gs and PKC. PMID- 9371734 TI - Regulation by glucocorticoids of angiotensinogen gene expression and secretion in adipose cells. AB - Adipose cells are an important source of angiotensinogen (AT). Its activation product, angiotensin II, stimulates in vitro and in vivo the production and release of prostacyclin which acts as a potent adipogenic signal in promoting the terminal differentiation of preadipocytes to adipocytes. Since glucocorticoids are known to promote adipose cell differentiation in vitro as well as in vivo, their role in the regulation of AT gene expression and secretion has been investigated in cultured Ob1771 mouse adipose cells. In contrast with liver cells, which are the major source of AT and the target of several hormones for the regulation of its expression, adipose cells are only responsive to glucocorticoids, which are able to up-regulate AT gene expression and AT secretion rapidly and dose-dependently. On exposure to glucocorticoids, accumulation of AT mRNA appears primarily to be due to transcriptional activation of the gene and is parallelled by secretion of the protein. Similar results on AT mRNA expression and AT secretion were obtained using explants of rat adipose tissue ex vivo demonstrating a major if not exclusive mechanism of regulation of AT production by glucocorticoids in mature adipose cells. Together these results provide a potential link between glucocorticoids, AT, the growth of adipose tissue and increased blood pressure. PMID- 9371736 TI - A new class of cytochrome b5 fusion proteins. PMID- 9371735 TI - Induction of the E-selectin promoter by interleukin 1 and tumour necrosis factor alpha, and inhibition by glucocorticoids. AB - Cytokine-induced expression of the endothelial cell surface adhesion molecule E selectin is inhibited by glucocorticoids (GCs). To investigate possible mechanisms for steroid inhibition, a reporter gene (ESAP) was constructed, comprising the cytokine responsive region of the E-selectin gene (nt -383 to +81) coupled to alkaline phosphatase (AP). In A549 cells stably transfected with the ESAP gene, AP production was highly responsive to the cytokines interleukin 1beta (IL-1beta) and tumour necrosis factor alpha, with ED50 values of 3 pM and 1000 pM respectively. Furthermore the cytokine-induced AP responses were inhibited by GCs, indicating that both transcriptional activation and GC suppression of the E selectin gene were mediated via regulatory elements within the same region of the promoter. The relative potencies of GC drugs as inhibitors of IL-1beta (10 pM) stimulated ESAP-gene activation were fluticasone> beclomethasone>dexamethasone, with IC50 values of 0.13, 1.1 and 2.7 nM respectively. Inhibition by fluticasone was blocked by the GC receptor (GR) antagonist drug mifepristone (Ru486), which is consistent with the suppressive effects of GCs being mediated via the GR. However, because the E-selectin promoter lacks a consensus glucocorticoid responsive element, mechanisms for inhibition independent of GR-DNA binding were investigated. Evidence that GCs also inhibited cytokine activation of a synthetic nuclear factor kappaB (NFkappaB)-driven reporter gene transiently transfected into A549 cells suggested that interference with the activation and/or function of this transcription factor was important for GC inhibition of ESAP. However, in A549-ESAP cells, fluticasone (100 nM) did not affect IL-1beta (10 pM)-induced IkBalpha degradation, NFkappaB-p65 nuclear translocation or the DNA-binding capacity of nuclear NFkappaB complexes, over a period during which cytokine induced ESAP-gene activation was inhibited. Finally, there was no evidence to suggest that GC enhancement of IkBalpha gene expression contributed to the suppression of the cytokine response. We conclude that interference by GR with the transcriptional activation potential of DNA-bound NFkappaB complexes might contribute to mechanisms underlying the anti-inflammatory effects of GCs. PMID- 9371737 TI - Do these sequences make CENs yet? PMID- 9371738 TI - WebWise: navigating the Human Genome Project. PMID- 9371739 TI - The importance of fungi to man. PMID- 9371740 TI - Arabidopsis thaliana centromere regions: genetic map positions and repetitive DNA structure. AB - The genetic positions of the five Arabidopsis thaliana centromere regions have been identified by mapping size polymorphisms in the centromeric 180-bp repeat arrays. Structural and genetic analysis indicates that 180-bp repeat arrays of up to 1000 kb are found in the centromere region of each chromosome. The genetic behavior of the centromeric arrays suggests that recombination within the arrays is suppressed. These results indicate that the centromere regions of A. thaliana resemble human centromeres in size and genomic organization. PMID- 9371741 TI - Steady-state transcript levels of the porphobilinogen deaminase gene in patients with acute intermittent porphyria. AB - PCR-based solid-phase minisequencing method was used to analyze the steady-state mRNA levels of the porphobilinogen deaminase gene in eight patients with acute intermittent porphyria. The patients had the earlier characterized mutations 517C --> T (R173W), 518G --> A (R173Q), 673C --> G (R225G), 673C --> T (R225X), 713T - > G (L278P), and 1073delA (frame shift). All mutations, except the missense mutation 517C --> T in exon 10, affected the steady-state transcript levels of the mutant allele. The mutant mRNA levels in lymphocytes varied from 5% to 95% of the corresponding wild-type allele levels. In contrast to the CRIM-negative mutation 517C --> T, the CRIM-positive mutation in the same codon 518G --> A resulted in reduction of the steady-state transcript level of the mutant allele to 65% of that of the normal allele. The two mutations, 673C --> G or T, affecting the same nucleotide in exon 12 also differed considerably in their effect on mRNA levels: The transcript level of the allele with a missense mutation was decreased to 80% of that of the normal allele, whereas a nonsense mutation at the same position resulted in a dramatic decrease (fivefold) in the levels of the mutant transcript. Our data showed large variations between the levels of mutant transcript in AIP patients and these variations did not correlate either to CRIM class, to the location of the disease causing mutation in the PBGD gene, or to the clinical phenotype of AIP. PMID- 9371743 TI - High throughput fingerprint analysis of large-insert clones. AB - As part of the Human Genome Project, the Washington University Genome Sequencing Center has commenced systematic sequencing of human chromsome 7. To organize and supply the effort, we have undertaken the construction of sequence-ready physical maps for defined chromosomal intervals. Map construction is a serial process composed of three main activities. First, candidate STS-positive large-insert PAC and BAC clones are identified. Next, these candidate clones are subjected to fingerprint analysis. Finally, the fingerprint data are used to assemble sequence ready maps. The fingerprinting method we have devised is key to the success of the overall approach. We present here the details of the method and show that the fingerprints are of sufficient quality to permit the construction of megabase size contigs in defined regions of the human genome. We anticipate that the high throughput and precision characteristic of our fingerprinting method will make it of general utility. PMID- 9371742 TI - Alu insertion polymorphisms and human evolution: evidence for a larger population size in Africa. AB - Alu insertion polymorphisms (polymorphisms consisting of the presence/absence of an Alu element at a particular chromosomal location) offer several advantages over other nuclear DNA polymorphisms for human evolution studies. First, they are typed by rapid, simple, PCR-based assays; second, they are stable polymorphisms newly inserted Alu elements rarely undergo deletion; third, the presence of an Alu element represents identity by descent-the probability that different Alu elements would independently insert into the exact same chromosomal location is negligible; and fourth, the ancestral state is known with certainty to be the absence of an Alu element. We report here a study of 8 loci in 1500 individuals from 34 worldwide populations. African populations exhibit the most between population differentiation, and the population tree is rooted in Africa; moreover, the estimated effective time of separation of African versus non African populations is 137,000 +/- 15,000 years ago, in accordance with other genetic data. However, a principal coordinates analysis indicates that populations from Sahul (Australia and New Guinea) are nearly as close to the hypothetical ancestor as are African populations, suggesting that there was an early expansion of tropical populations of our species. An analysis of heterozygosity versus genetic distance suggests that African populations have had a larger effective population size than non-African populations. Overall, these results support the African origin of modern humans in that an earlier expansion of the ancestors of African populations is indicated. PMID- 9371745 TI - A streamlined mutation detection system: multicolor post-PCR fluorescence labeling and single-strand conformational polymorphism analysis by capillary electrophoresis. AB - Effective use of knowledge of human genome sequences in studies of hereditary diseases or cancer heavily depends on efficient methods for detection of mutations in individual samples. We describe here a simple and efficient mutation scanning system in which PCR products are post-labeled with two different fluorescent dyes in one tube, and analyzed by an automated capillary electrophoresis system using single-strand conformation polymorphism (SSCP) conditions (PLACE-SSCP). With the appropriate use of an internal control DNA, differences in electrophoretic mobilities between a reference and samples are precisely evaluated, then the presence of mutations is statistically judged. Thirty-three of 34 known mutations in fragments of three unrelated sequence contexts up to 741 bp were detected using one electrophoresis condition at the confidence level of <0.3% false positive. All the mutations were detected by analyzing at two temperatures. The described system has the advantage of little human intervention, short analysis time, high sensitivity, and objectivity of data interpretation. PMID- 9371744 TI - Genetic mapping of 262 loci derived from expressed sequences in a murine interspecific cross using single-strand conformational polymorphism analysis. AB - We have demonstrated previously that noncoding sequences of genes are a robust source of polymorphisms between mouse species when tested using single-strand conformation polymorphism (SSCP) analysis, and that these polymorphisms are useful for genetic mapping. In this report we demonstrate that presumptive 3' untranslated region sequence obtained from expressed sequence tags (ESTs) can be analyzed in a similar fashion, and we have used this approach to map 262 loci using an interspecific backcross. These results demonstrate SSCP analysis of genes or ESTs is a simple and efficient means for the genetic localization of transcribed sequences, and is furthermore an approach that is applicable to any system for which there is sufficient sequence polymorphism. PMID- 9371746 TI - A simple method for automated allele binning in microsatellite markers. AB - High-throughput fluorescent genotyping requires a considerable amount of automation for accurate and efficient processing of genetic markers. Automated DNA sequencers and corresponding software products are commercially available that contribute substantially to increased throughput rates for large-scale genotyping projects. However, some conceptually simple tasks still require time consuming manual intervention that imposes bottlenecks on throughput capacity. One of these tasks is the conversion of imprecise DNA fragment sizes determined by commercial software programs to the underlying discrete alleles that the sizes represent. Here we describe a simple method for assigning allele sizes into their appropriate allele "bins" using least-squares minimization procedures. The method requires no special treatment of family data on plates, internal/external size standards, or electropherogram data manipulation. Tests of the method using the ABI 373A automated DNA sequencer and accompanying Genescan/Genotyper software resulted in accurate automatic classification of all alleles in >80% of 208 markers analyzed, with the remaining 20% being appropriately identified as requiring additional attention to laboratory conditions. Specific characteristics of different markers, including differences in PCR product size and inexact repeat lengths (e.g., 1. 9 bp for a dinucleotide repeat), are accommodated by the method and their properties discussed. PMID- 9371751 TI - Estimating the probability of initiated cell death before tumor induction. AB - The effects of cell toxicity are known to be inherent in carcinogenesis induced by radiation or chemical carcinogens. The event of cell death precludes tumor induction from occurring. A long standing problem is to estimate the proportion of initiated cells that die before tumor induction. No experimental techniques are currently available for directly gauging the rate of cell death over extended periods of time. The obstacle can be surmounted by newly developed theoretical methods of carcinogenesis modeling. In this paper, we apply such methods to published data on multiple lung tumors in mice receiving different schedules of urethane. Bioassays of this type play an important role in testing environmental chemicals for carcinogenic activity. Our estimates for urethane-induced carcinogenesis show that, unexpectedly, many initiated cells die early in the course of tumor promotion. We present numerical estimates for the probability of initiated cell death for different schedules (and doses) of urethane administration. PMID- 9371752 TI - Global variation in the genetic and biochemical basis of diamondback moth resistance to Bacillus thuringiensis. AB - Insecticidal proteins from the soil bacterium Bacillus thuringiensis (Bt) are becoming a cornerstone of ecologically sound pest management. However, if pests quickly adapt, the benefits of environmentally benign Bt toxins in sprays and genetically engineered crops will be short-lived. The diamondback moth (Plutella xylostella) is the first insect to evolve resistance to Bt in open-field populations. Here we report that populations from Hawaii and Pennsylvania share a genetic locus at which a recessive mutation associated with reduced toxin binding confers extremely high resistance to four Bt toxins. In contrast, resistance in a population from the Philippines shows multilocus control, a narrower spectrum, and for some Bt toxins, inheritance that is not recessive and not associated with reduced binding. The observed variation in the genetic and biochemical basis of resistance to Bt, which is unlike patterns documented for some synthetic insecticides, profoundly affects the choice of strategies for combating resistance. PMID- 9371753 TI - Estrogenic responses in estrogen receptor-alpha deficient mice reveal a distinct estrogen signaling pathway. AB - Estrogens are thought to regulate female reproductive functions by altering gene transcription in target organs primarily via the nuclear estrogen receptor-alpha (ER-alpha). By using ER-alpha "knock-out" (ERKO) mice, we demonstrate herein that a catecholestrogen, 4-hydroxyestradiol-17beta (4-OH-E2), and an environmental estrogen, chlordecone (kepone), up-regulate the uterine expression of an estrogen responsive gene, lactoferrin (LF), independent of ER-alpha. A primary estrogen, estradiol-17beta (E2), did not induce this LF response. An estrogen receptor antagonist, ICI-182,780, or E2 failed to inhibit uterine LF gene expression induced by 4-OH-E2 or kepone in ERKO mice, which suggests that this estrogen signaling pathway is independent of both ER-alpha and the recently cloned ER beta. 4-OH-E2, but not E2, also stimulated increases in uterine water imbibition and macromolecule uptake in ovariectomized ERKO mice. The results strongly imply the presence of a distinct estrogen-signaling pathway in the mouse uterus that mediates the effects of both physiological and environmental estrogens. This estrogen response pathway will have profound implications for our understanding of the physiology and pathophysiology of female sex steroid hormone actions in target organs. PMID- 9371754 TI - KSR stimulates Raf-1 activity in a kinase-independent manner. AB - Kinase suppressor of Ras (KSR) is an evolutionarily conserved component of Ras dependent signaling pathways. Here, we find that murine KSR (mKSR1) translocates from the cytoplasm to the plasma membrane in the presence of activated Ras. At the membrane, mKSR1 modulates Ras signaling by enhancing Raf-1 activity in a kinase-independent manner. The activation of Raf-1 is mediated by the mKSR1 cysteine-rich CA3 domain and involves a detergent labile cofactor that is not ceramide. These findings reveal another point of regulation for Ras-mediated signal transduction and further define a noncatalytic role for mKSR1 in the multistep process of Raf-1 activation. PMID- 9371755 TI - A link between protein structure and enzyme catalyzed hydrogen tunneling. AB - We present evidence that the size of an active site side chain may modulate the degree of hydrogen tunneling in an enzyme-catalyzed reaction. Primary and secondary kH/kT and kD/kT kinetic isotope effects have been measured for the oxidation of benzyl alcohol catalyzed by horse liver alcohol dehydrogenase at 25 degrees C. As reported in earlier studies, the relationship between secondary kH/kT and kD/kT isotope effects provides a sensitive probe for deviations from classical behavior. In the present work, catalytic efficiency and the extent of hydrogen tunneling have been correlated for the alcohol dehydrogenase-catalyzed hydride transfer among a group of site-directed mutants at position 203. Val-203 interacts with the opposite face of the cofactor NAD+ from the alcohol substrate. The reduction in size of this residue is correlated with diminished tunneling and a two orders of magnitude decrease in catalytic efficiency. Comparison of the x ray crystal structures of a ternary complex of a high-tunneling (Phe-93 --> Trp) and a low-tunneling (Val-203 --> Ala) mutant provides a structural basis for the observed effects, demonstrating an increase in the hydrogen transfer distance for the low-tunneling mutant. The Val-203 --> Ala ternary complex crystal structure also shows a hyperclosed interdomain geometry relative to the wild-type and the Phe-93 --> Trp mutant ternary complex structures. This demonstrates a flexibility in interdomain movement that could potentially narrow the distance between the donor and acceptor carbons in the native enzyme and may enhance the role of tunneling in the hydride transfer reaction. PMID- 9371756 TI - The carbamate kinase-like carbamoyl phosphate synthetase of the hyperthermophilic archaeon Pyrococcus furiosus, a missing link in the evolution of carbamoyl phosphate biosynthesis. AB - Microbial carbamoyl phosphate synthetases (CPS) use glutamine as nitrogen donor and are composed of two subunits (or domains), one exhibiting glutaminase activity, the other able to synthesize carbamoyl phosphate (CP) from bicarbonate, ATP, and ammonia. The pseudodimeric organization of this synthetase suggested that it has evolved by duplication of a smaller kinase, possibly a carbamate kinase (CK). In contrast to other prokaryotes the hyperthermophilic archaeon Pyrococcus furiosus was found to synthesize CP by using ammonia and not glutamine. We have purified the cognate enzyme and found it to be a dimer of two identical subunits of Mr 32,000. Its thermostability is considerable, 50% activity being retained after 1 h at 100 degrees C or 3 h at 95 degrees C. The corresponding gene was cloned by PCR and found to present about 50% amino acid identity with known CKs. The stoichiometry of the reaction (two ATP consumed per CP synthesized) and the ability of the enzyme to catalyze at high rate a bicarbonate-dependent ATPase reaction however clearly distinguish P. furiosus CPS from ordinary CKs. Thus the CPS of P. furiosus could represent a primeval step in the evolution of CPS from CK. Our results suggest that the first event in this evolution was the emergence of a primeval synthetase composed of subunits able to synthesize both carboxyphosphate and CP; this step would have preceded the duplication assumed to have generated the two subdomains of modern CPSs. The gene coding for this CK-like CPS was called cpkA. PMID- 9371757 TI - The diversity and evolutionary relationships of the pregnancy-associated glycoproteins, an aspartic proteinase subfamily consisting of many trophoblast expressed genes. AB - The pregnancy-associated glycoproteins (PAGs) are structurally related to the pepsins, thought to be restricted to the hooved (ungulate) mammals and characterized by being expressed specifically in the outer epithelial cell layer (chorion/trophectoderm) of the placenta. At least some PAGs are catalytically inactive as proteinases, although each appears to possess a cleft capable of binding peptides. By cloning expressed genes from ovine and bovine placental cDNA libraries, by Southern genomic blotting, by screening genomic libraries, and by using PCR to amplify portions of PAG genes from genomic DNA, we estimate that cattle, sheep, and most probably all ruminant Artiodactyla possess many, possibly 100 or more, PAG genes, many of which are placentally expressed. The PAGs are highly diverse in sequence, with regions of hypervariability confined largely to surface-exposed loops. Nonsynonymous (replacement) mutations in the regions of the genes coding for these hypervariable loop segments have accumulated at a higher rate than synonymous (silent) mutations. Construction of distance phylograms, based on comparisons of PAG and related aspartic proteinase amino acid sequences, suggests that much diversification of the PAG genes occurred after the divergence of the Artiodactyla and Perissodactyla, but that at least one gene is represented outside the hooved species. The results also suggest that positive selection of duplicated genes has acted to provide considerable functional diversity among the PAGs, whose presence at the interface between the placenta and endometrium and in the maternal circulation indicates involvement in fetal-maternal interactions. PMID- 9371758 TI - Localization and activity of lysyl oxidase within nuclei of fibrogenic cells. AB - Lysyl oxidase (EC 1.4.3.13) oxidizes peptidyl lysine to peptidyl aldehyde residues within collagen and elastin, thus initiating formation of the covalent cross-linkages that insolubilize these extracellular proteins. Recent findings raise the possibility that this enzyme may also function intracellularly. The present study provides evidence by immunocytochemical confocal microscopy, Western blot analysis, enzyme assays, and chemical analyses for lysyl oxidase reaction products that this enzyme is present and active within rat vascular smooth muscle cell nuclei. Confocal microscopy indicates its presence within nuclei of 3T3 fibroblasts, as well. PMID- 9371759 TI - Identification of specific Rp-phosphate oxygens in the tRNA anticodon loop required for ribosomal P-site binding. AB - tRNA binding to the ribosomal P site is dependent not only on correct codon anticodon interaction but also involves identification of structural elements of tRNA by the ribosome. By using a phosphorothioate substitution-interference approach, we identified specific nonbridging Rp-phosphate oxygens in the anticodon loop of tRNA(Phe) from Escherichia coli which are required for P-site binding. Stereospecific involvement of phosphate oxygens at these positions was confirmed by using synthetic anticodon arm analogues at which single Rp- or Sp phosphorothioates were incorporated. Identical interference results with yeast tRNA(Phe) and E. coli tRNA(fMet) indicate a common backbone conformation or common recognition elements in the anticodon loop of tRNAs. N-ethyl-N-nitrosourea modification-interference experiments with natural tRNAs point to the importance of the same phosphates in the loop. Guided by the crystal structure of tRNA(Phe), we propose that specific Rp-phosphate oxygens are required for anticodon loop ("U turn") stabilization or are involved in interactions with the ribosome on correct tRNA-mRNA complex formation. PMID- 9371760 TI - Recruitment of IRAK to the interleukin 1 receptor complex requires interleukin 1 receptor accessory protein. AB - The proinflammatory cytokine interleukin 1 (IL-1) activates the transcription of many genes encoding acute phase and proinflammatory proteins, a function mediated primarily by the transcription factor NF-kappaB. An early IL-1 signaling event is the recruitment of the Ser/Thr kinase IRAK to the type I IL-1 receptor (IL-1RI). Here we describe the function of a previously identified IL-1 receptor subunit designated IL-1 receptor accessory protein (IL-1RAcP). IL-1 treatment of cells induces the formation of a complex containing both IL-1RI and IL-1RAcP. IRAK is recruited to this complex through its association with IL-1RAcP. Overexpression of an IL-1RAcP mutant lacking its intracellular domain, the IRAK-binding domain, prevented the recruitment of IRAK to the receptor complex and blocked IL-1 induced NF-kappaB activation. PMID- 9371761 TI - Isolation and bacterial expression of a sesquiterpene synthase cDNA clone from peppermint (Mentha x piperita, L.) that produces the aphid alarm pheromone (E) beta-farnesene. AB - (E)-beta-Farnesene is a sesquiterpene semiochemical that is used extensively by both plants and insects for communication. This acyclic olefin is found in the essential oil of peppermint (Mentha x piperita) and can be synthesized from farnesyl diphosphate by a cell-free extract of peppermint secretory gland cells. A cDNA from peppermint encoding (E)-beta-farnesene synthase was cloned by random sequencing of an oil gland library and was expressed in Escherichia coli. The corresponding synthase has a deduced size of 63.8 kDa and requires a divalent cation for catalysis (Km for Mg2+ approximately 150 microM; Km for Mn2+ approximately 7 microM). The sesquiterpenoids produced by the recombinant enzyme, as determined by radio-GC and GC-MS, are (E)-beta-farnesene (85%), (Z)-beta farnesene (8%), and delta-cadinene (5%) with the native C15 substrate farnesyl diphosphate (Km approximately 0.6 microM; Vrel = 100) and Mg2+ as cofactor, and (E)-beta-farnesene (98%) and (Z)-beta-farnesene (2%) with Mn2+ as cofactor (Vrel = 80). With the C10 analog, GDP, as substrate (Km = 1.5 microM; Vrel = 3 with Mg2+ as cofactor), the monoterpenes limonene (48%), terpinolene (15%), and myrcene (15%) are produced. PMID- 9371762 TI - Anti-idiotype RNA selected with an anti-nuclear export signal antibody is actively transported in oocytes and inhibits Rev- and cap-dependent RNA export. AB - The anti-idiotype approach is based on the assumption that an antibody specific for a receptor-binding domain of a ligand could be structurally related to the receptor. Therefore, a structural mimic of a receptor-binding domain, selected with an anti-ligand antibody, might be a functional substrate for the receptor. This hypothesis was addressed here by generating antibodies recognizing the Rev nuclear export signal (NES). A functional NES is required for active export, presumably by interacting directly or indirectly with the nuclear pore complex. Anti-NES antibodies were used to isolate RNA mimics of the NES peptide from combinatorial RNA libraries. The RNA-mimics are exported actively, block Rev dependent export of a reporter RNA, and inhibit cap-dependent U1 snRNA export in Xenopus oocytes, properties previously reported for NES-peptide conjugates. PMID- 9371763 TI - Functional analysis of DNA bending and unwinding by the high mobility group domain of LEF-1. AB - LEF-1 (lymphoid enhancer-binding factor 1) is a cell type-specific member of the family of high mobility group (HMG) domain proteins that recognizes a specific nucleotide sequence in the T cell receptor (TCR) alpha enhancer. In this study, we extend the analysis of the DNA-binding properties of LEF-1 and examine their contributions to the regulation of gene expression. We find that LEF-1, like nonspecific HMG-domain proteins, can interact with irregular DNA structures such as four-way junctions, albeit with lower efficiency than with specific duplex DNA. We also show by a phasing analysis that the LEF-induced DNA bend is directed toward the major groove. In addition, we find that the interaction of LEF-1 with a specific binding site in circular DNA changes the linking number of DNA and unwinds the double helix. Finally, we identified two nucleotides in the LEF-1 binding site that are important for protein-induced DNA bending. Mutations of these nucleotides decrease both the extent of DNA bending and the transactivation of the TCR alpha enhancer by LEF-1, suggesting a contribution of protein-induced DNA bending to the function of TCR alpha enhancer. PMID- 9371764 TI - Inhibition of regulator of G protein signaling function by two mutant RGS4 proteins. AB - Regulators of G protein signaling (RGS) proteins limit the lifetime of activated (GTP-bound) heterotrimeric G protein a subunits by acting as GTPase-activating proteins (GAPs). Mutation of two residues in RGS4, which, based on the crystal structure of RGS4 complexed with G(i alpha1)-GDP-AIF4-, directly contact G(i alpha1) (N88 and L159), essentially abolished RGS4 binding and GAP activity. Mutation of another contact residue (S164) partially inhibited both binding and GAP activity. Two other mutations, one of a contact residue (R167M/A) and the other an adjacent residue (F168A), also significantly reduced RGS4 binding to G(i alpha1)-GDP-AIF4-, but in addition redirected RGS4 binding toward the GTPgammaS bound form. These two mutant proteins had severely impaired GAP activity, but in contrast to the others behaved as RGS antagonists in GAP and in vivo signaling assays. Overall, these results are consistent with the hypothesis that the predominant role of RGS proteins is to stabilize the transition state for GTP hydrolysis. In addition, mutant RGS proteins can be created with an altered binding preference for the G(i alpha)-GTP conformation, suggesting that efficient RGS antagonists can be developed. PMID- 9371765 TI - Identification of a thiamin-dependent synthase in Escherichia coli required for the formation of the 1-deoxy-D-xylulose 5-phosphate precursor to isoprenoids, thiamin, and pyridoxol. AB - In Escherichia coli, 1-deoxy-D-xylulose (or its 5-phosphate, DXP) is the biosynthetic precursor to isopentenyl diphosphate [Broers, S. T. J. (1994) Dissertation (Eidgenossische Technische Hochschule, Zurich)], thiamin, and pyridoxol [Himmeldirk, K., Kennedy, I. A., Hill, R. E., Sayer, B. G. & Spenser, I. D. (1996) Chem. Commun. 1187-1188]. Here we show that an open reading frame at 9 min on the chromosomal map of E. coli encodes an enzyme (deoxyxylulose-5 phosphate synthase, DXP synthase) that catalyzes a thiamin diphosphate-dependent acyloin condensation reaction between C atoms 2 and 3 of pyruvate and glyceraldehyde 3-phosphate to yield DXP. We have cloned and overexpressed the gene (dxs), and the enzyme was purified 17-fold to a specific activity of 0.85 unit/mg of protein. The reaction catalyzed by DXP synthase yielded exclusively DXP, which was characterized by 1H and 31P NMR spectroscopy. Although DXP synthase of E. coli shows sequence similarity to both transketolases and the E1 subunit of pyruvate dehydrogenase, it is a member of a distinct protein family, and putative DXP synthase sequences appear to be widespread in bacteria and plant chloroplasts. PMID- 9371766 TI - An interaction between DNA ligase I and proliferating cell nuclear antigen: implications for Okazaki fragment synthesis and joining. AB - Although three human genes encoding DNA ligases have been isolated, the molecular mechanisms by which these gene products specifically participate in different DNA transactions are not well understood. In this study, fractionation of a HeLa nuclear extract by DNA ligase I affinity chromatography resulted in the specific retention of a replication protein, proliferating cell nuclear antigen (PCNA), by the affinity resin. Subsequent experiments demonstrated that DNA ligase I and PCNA interact directly via the amino-terminal 118 aa of DNA ligase I, the same region of DNA ligase I that is required for localization of this enzyme at replication foci during S phase. PCNA, which forms a sliding clamp around duplex DNA, interacts with DNA pol delta and enables this enzyme to synthesize DNA processively. An interaction between DNA ligase I and PCNA that is topologically linked to DNA was detected. However, DNA ligase I inhibited PCNA-dependent DNA synthesis by DNA pol delta. These observations suggest that a ternary complex of DNA ligase I, PCNA and DNA pol delta does not form on a gapped DNA template. Consistent with this idea, the cell cycle inhibitor p21, which also interacts with PCNA and inhibits processive DNA synthesis by DNA pol delta, disrupts the DNA ligase I-PCNA complex. Thus, we propose that after Okazaki fragment DNA synthesis is completed by a PCNA-DNA pol delta complex, DNA pol delta is released, allowing DNA ligase I to bind to PCNA at the nick between adjacent Okazaki fragments and catalyze phosphodiester bond formation. PMID- 9371767 TI - Targeted deletion of alkylpurine-DNA-N-glycosylase in mice eliminates repair of 1,N6-ethenoadenine and hypoxanthine but not of 3,N4-ethenocytosine or 8 oxoguanine. AB - It has previously been reported that 1,N6-ethenoadenine (epsilonA), deaminated adenine (hypoxanthine, Hx), and 7,8-dihydro-8-oxoguanine (8-oxoG), but not 3,N4 ethenocytosine (epsilonC), are released from DNA in vitro by the DNA repair enzyme alkylpurine-DNA-N-glycosylase (APNG). To assess the potential contribution of APNG to the repair of each of these mutagenic lesions in vivo, we have used cell-free extracts of tissues from APNG-null mutant mice and wild-type controls. The ability of these extracts to cleave defined oligomers containing a single modified base was determined. The results showed that both testes and liver cells of these knockout mice completely lacked activity toward oligonucleotides containing epsilonA and Hx, but retained wild-type levels of activity for epsilonC and 8-oxoG. These findings indicate that (i) the previously identified epsilonA-DNA glycosylase and Hx-DNA glycosylase activities are functions of APNG; (ii) the two structurally closely related mutagenic adducts epsilonA and epsilonC are repaired by separate gene products; and (iii) APNG does not contribute detectably to the repair of 8-oxoG. PMID- 9371768 TI - Construction of a Z-DNA-specific restriction endonuclease. AB - Novel restriction enzymes can be created by fusing the nuclease domain of FokI endonuclease with defined DNA binding domains. Recently, we have characterized a domain (Z alpha) from the N-terminal region of human double-stranded RNA adenosine deaminase (hADAR1), which binds the Z-conformation with high specificity. Here we report creation of a conformation-specific endonuclease, Z alpha nuclease, which is a chimera of Z alpha and FokI nuclease. Purified Z alpha nuclease cleaves negatively supercoiled plasmids only when they contain a Z-DNA forming insert, such as (dC-dG)13. The precise location of the cleavage sites was determined by primer extension. Cutting has been mapped to the edge of the B-Z junction, suggesting that Z alpha nuclease binds within the Z-DNA insert, but cleaves in the nearby B-DNA, by using a mechanism similar to type IIs restriction enzymes. These data show that Z alpha binds Z-DNA in an environment similar to that in a cell. Z alpha nuclease, a structure-specific restriction enzyme, may be a useful tool for further study of the biological role of Z-DNA. PMID- 9371769 TI - Disruption of the murine gene encoding phosphatidylethanolamine N methyltransferase. AB - All nucleated cells make phosphatidylcholine via the CDP-choline pathway. Liver has an alternative pathway in which phosphatidylcholine is made by methylation of phosphatidylethanolamine catalyzed by phosphatidylethanolamine N methyltransferase (PEMT). We investigated the function of PEMT and its role in animal physiology by targeted disruption of its gene, Pempt2. A targeting vector that interrupts exon 2 was constructed and introduced into mice yielding three genotypes: normal (+/+), heterozygotes (+/-), and homozygotes (-/-) for the disrupted PEMT gene. Only a trace of PE methylation activity remained in Pempt2( /-) mice. Antibody to one form of the enzyme, PEMT2, indicated complete loss of this protein from Pempt2(-/-) mice and a decrease in Pempt2(+/-) mice, compared with Pempt2(+/+) mice. The levels of hepatic phosphatidylethanolamine and phosphatidylcholine were minimally affected. The active form of CTP:phosphocholine cytidylyltransferase, the regulated enzyme in the CDP-choline pathway, was increased 60% in the PEMT-deficient mice. Injection of [L-methyl 3H]methionine demonstrated that the in vivo PEMT activity was eliminated in the Pempt2(-/-) mice and markedly decreased in the Pempt2(+/-) mice. This experiment also demonstrated that the choline moiety derived from PEMT in the liver can be distributed via the plasma throughout the mouse where it is found as phosphatidylcholine, lysophosphatidylcholine, and sphingomyelin. Mice homozygous for the disrupted Pempt2 gene displayed no abnormal phenotype, normal hepatocyte morphology, normal plasma lipid levels and no differences in bile composition. This is the first application of the "knockout mouse" technique to a gene for phospholipid biosynthesis. PMID- 9371770 TI - Myc represses transcription of the growth arrest gene gas1. AB - Cell proliferation is regulated by the induction of growth promoting genes and the suppression of growth inhibitory genes. Malignant growth can result from the altered balance of expression of these genes in favor of cell proliferation. Induction of the transcription factor, c-Myc, promotes cell proliferation and transformation by activating growth promoting genes, including the ODC and cdc25A genes. We show that c-Myc transcriptionally represses the expression of a growth arrest gene, gas1. A conserved Myc structure, Myc box 2, is required for repression of gas1, and for Myc induction of proliferation and transformation, but not for activation of ODC. Activation of a Myc-estrogen receptor fusion protein by 4-hydroxytamoxifen was sufficient to repress gas1 gene transcription. These findings suggest that transcriptional repression of growth arrest genes, including gas1, is one step in promotion of cell growth by Myc. PMID- 9371771 TI - Proteins on ribosome surface: measurements of protein exposure by hot tritium bombardment technique. AB - The hot tritium bombardment technique [Goldanskii, V. I., Kashirin, I. A., Shishkov, A. V., Baratova, L. A. & Grebenshchikov, N. I. (1988) J. Mol. Biol. 201,567-574] has been applied to measure the exposure of proteins on the ribosomal surface. The technique is based on replacement of hydrogen by high energy tritium atoms in thin surface layer of macromolecules. Quantitation of tritium radioactivity of each protein has revealed that proteins S1, S4, S5, S7, S18, S20, and S21 of the small subunit, and proteins L7/L12, L9, L10, L11, L16, L17, L24, and L27 of the large subunit are well exposed on the surface of the Escherichia coli 70 S ribosome. Proteins S8, S10, S12, S16, S17, L14, L20, L29, L30, L31, L32, L33, and L34 have virtually no groups exposed on the ribosomal surface. The remaining proteins are found to be exposed to lesser degree than the well exposed ones. No additional ribosomal proteins was exposed upon dissociation of ribosomes into subunits, thus indicating the absence of proteins on intersubunit contacting surfaces. PMID- 9371773 TI - Inhibition of NF-kappaB DNA binding and nitric oxide induction in human T cells and lung adenocarcinoma cells by selenite treatment. AB - NF-kappaB is a major transcription factor consisting of 50(p50)- and 65(p65)-kDa proteins that controls the expression of various genes, among which are those encoding cytokines, cell adhesion molecules, and inducible NO synthase (iNOS). After initial activation of NF-kappaB, which involves release and proteolysis of a bound inhibitor, essential cysteine residues are maintained in the active reduced state through the action of thioredoxin and thioredoxin reductase. In the present study, activation of NF-kappaB in human T cells and lung adenocarcinoma cells was induced by recombinant human tumor necrosis factor alpha or bacterial lipopolysaccharide. After lipopolysaccharide activation, nuclear extracts were treated with increasing concentrations of selenite, and the effects on DNA binding activity of NF-kappaB were examined. Binding of NF-kappaB to nuclear responsive elements was decreased progressively by increasing selenite levels and, at 7 microM selenite, DNA-binding activity was completely inhibited. Selenite inhibition was reversed by addition of a dithiol, DTT. Proportional inhibition of iNOS activity as measured by decreased NO products in the medium (NO2- and NO3-) resulted from selenite addition to cell suspensions. This loss of iNOS activity was due to decreased synthesis of NO synthase protein. Selenium at low essential levels (nM) is required for synthesis of redox active selenoenzymes such as glutathione peroxidases and thioredoxin reductase, but in higher toxic levels (>5-10 microM) selenite can react with essential thiol groups on enzymes to form RS-Se-SR adducts with resultant inhibition of enzyme activity. Inhibition of NF-kappaB activity by selenite is presumed to be the result of adduct formation with the essential thiols of this transcription factor. PMID- 9371772 TI - Mammalian capping enzyme complements mutant Saccharomyces cerevisiae lacking mRNA guanylyltransferase and selectively binds the elongating form of RNA polymerase II. AB - 5'-Capping is an early mRNA modification that has important consequences for downstream events in gene expression. We have isolated mammalian cDNAs encoding capping enzyme. They contain the sequence motifs characteristic of the nucleotidyl transferase superfamily. The predicted mouse and human enzymes consist of 597 amino acids and are 95% identical. Mouse cDNA directed synthesis of a guanylylated 68-kDa polypeptide that also contained RNA 5'-triphosphatase activity and catalyzed formation of RNA 5'-terminal GpppG. A haploid strain of Saccharomyces cerevisiae lacking mRNA guanylyltransferase was complemented for growth by the mouse cDNA. Conversion of Lys-294 in the KXDG-conserved motif eliminated both guanylylation and complementation, identifying it as the active site. The K294A mutant retained RNA 5'-triphosphatase activity, which was eliminated by N-terminal truncation. Full-length capping enzyme and an active C terminal fragment bound to the elongating form and not to the initiating form of polymerase. The results document functional conservation of eukaryotic mRNA guanylyltransferases from yeast to mammals and indicate that the phosphorylated C terminal domain of RNA polymerase II couples capping to transcription elongation. These results also explain the selective capping of RNA polymerase II transcripts. PMID- 9371774 TI - P-glycoprotein function involves conformational transitions detectable by differential immunoreactivity. AB - The MDR1 P-glycoprotein (Pgp), a member of the ATP-binding cassette family of transporters, is a transmembrane ATPase efflux pump for various lipophilic compounds, including many anti-cancer drugs. mAb UIC2, reactive with the extracellular moiety of Pgp, inhibits Pgp-mediated efflux. UIC2 reactivity with Pgp was increased by the addition of several Pgp-transported compounds or ATP depleting agents, and by mutational inactivation of both nucleotide-binding domains (NBDs) of Pgp. UIC2 binding to Pgp mutated in both NBDs was unaffected in the presence of Pgp transport substrates or in ATP-depleted cells, whereas the reactivities of the wild-type Pgp and Pgps mutated in a single NBD were increased by these treatments to the level of the double mutant. These results indicate the existence of different Pgp conformations associated with different stages of transport-associated ATP hydrolysis and suggest trapping in a transient conformation as a mechanism for antibody-mediated inhibition of Pgp. PMID- 9371775 TI - cAMP receptor protein-cAMP plays a crucial role in glucose-lactose diauxie by activating the major glucose transporter gene in Escherichia coli. AB - The inhibition of beta-galactosidase expression in a medium containing both glucose and lactose is a typical example of the glucose effect in Escherichia coli. We studied the glucose effect in the lacL8UV5 promoter mutant, which is independent of cAMP and cAMP receptor protein (CRP). A strong inhibition of beta galactosidase expression by glucose and a diauxic growth were observed when the lacL8UV5 cells were grown on a glucose-lactose medium. The addition of isopropyl beta-D-thiogalactoside to the culture medium eliminated the glucose effect. Disruption of the crr gene or overproduction of LacY also eliminated the glucose effect. These results are fully consistent with our previous finding that the glucose effect in wild-type cells growing in a glucose-lactose medium is not due to the reduction of CRP-cAMP levels but is due to the inducer exclusion. We found that the glucose effect in the lacL8UV5 cells was no longer observed when either the crp or the cya gene was disrupted. Evidence suggested that CRP-cAMP may not enhance directly the lac repressor action in vivo. Northern blot analysis revealed that the mRNA for ptsG, a major glucose transporter gene, was markedly reduced in a delta crp or delta cya background. The constitutive expression of the ptsG gene by the introduction of a multicopy plasmid restored the glucose effect in delta cya or delta crp cells. We conclude that CRP-cAMP plays a crucial role in inducer exclusion, which is responsible for the glucose-lactose diauxie, by activating the expression of the ptsG gene. PMID- 9371776 TI - Cloning and expression of rat 25-hydroxyvitamin D3-1alpha-hydroxylase cDNA. AB - A full-length cDNA for the rat kidney mitochondrial cytochrome P450 mixed function oxidase, 25-hydroxyvitamin D3-1alpha-hydroxylase (P4501alpha), was cloned from a vitamin D-deficient rat kidney cDNA library and subcloned into the mammalian expression vector pcDNA 3.1(+). When P4501alpha cDNA was transfected into COS-7 transformed monkey kidney cells, they expressed 25-hydroxyvitamin D3 1alpha-hydroxylase activity. The sequence analysis showed that P4501alpha was of 2,469 bp long and contained an ORF encoding 501 amino acids. The deduced amino acid sequence showed a 53% similarity and 44% identity to the vitamin D3-25 hydroxylase (CYP27), whereas it has 42.6% similarity and 34% identity with the 25 hydroxyvitamin D3-24-hydroxylase (CYP24). Thus, it composes a new subfamily of the CYP27 family. Further, it is more closely related to the CYP27 than to the CYP24. The expression of P4501alpha mRNA was greatly increased in the kidney of vitamin D-deficient rats. In rats with the enhanced renal production of 1alpha,25 dihydroxyvitamin D3 (rats fed a low Ca diet), P4501alpha mRNA was greatly increased in the renal proximal convoluted tubules. PMID- 9371777 TI - Cloning and expression of a cDNA encoding a bovine brain brefeldin A-sensitive guanine nucleotide-exchange protein for ADP-ribosylation factor. AB - A 200-kDa guanine nucleotide-exchange protein (p200 or GEP) for ADP-ribosylation factors 1 and 3 (ARF1 and ARF3) that was inhibited by brefeldin A (BFA) was purified earlier from cytosol of bovine brain cortex. Amino acid sequences of four tryptic peptides were 47% identical to that of Sec7 from Saccharomyces cerevisiae, which is involved in vesicular trafficking in the Golgi. By using a PCR-based procedure with two degenerate primers representing sequences of these peptides, a product similar in size to Sec7 that contained the peptide sequences was generated. Two oligonucleotides based on this product were used to screen a bovine brain library, which yielded one clone that was a partial cDNA for p200. The remainder of the cDNA was obtained by 5' and 3' rapid amplification of cDNA ends (RACE). The ORF of the cDNA encodes a protein of 1,849 amino acids (approximately 208 kDa) that is 33% identical to yeast Sec7 and 50% identical in the Sec7 domain region. On Northern blot analysis of bovine tissues, a approximately 7.4-kb mRNA was identified that hybridized with a p200 probe; it was abundant in kidney, somewhat less abundant in lung, spleen, and brain, and still less abundant in heart. A six-His-tagged fusion protein synthesized in baculovirus-infected Sf9 cells demonstrated BFA-inhibited GEP activity, confirming that BFA sensitivity is an intrinsic property of this ARF GEP and not conferred by another protein component of the complex from which p200 was originally purified. PMID- 9371778 TI - Phagocytosis of rod outer segments by retinal pigment epithelial cells requires alpha(v)beta5 integrin for binding but not for internalization. AB - Phagocytosis of shed photoreceptor rod outer segments (ROS) by the retinal pigment epithelium (RPE) is essential for retinal function. Here, we demonstrate that this process requires alpha(v)beta5 integrin, rather than alpha(v)beta3 integrin utilized by systemic macrophages. Although adult rat RPE expressed both alpha(v)beta3 and alpha(v)beta5 integrins, only alpha(v)beta3 was expressed at birth, when the retina is immature and phagocytosis is absent. Expression of alpha(v)beta5 was first detected in RPE at PN7 and reached adult levels at PN11, just before onset of phagocytic activity. Interestingly, alpha(v)beta5 localized in vivo to the apical plasma membrane, facing the photoreceptors, and to intracellular vesicles, whereas alpha(v)beta3 was expressed basolaterally. Using quantitative fluorimaging to assess in vitro uptake of fluorescent particles by human (ARPE-19) and rat (RPE-J) cell lines, alpha(v)beta5 function-blocking antibodies were shown to reduce phagocytosis by drastically decreasing (85%) binding of ROS but not of latex beads. In agreement with a role for alpha(v)beta5 in phagocytosis, immunofluorescence experiments demonstrated codistribution of alpha(v)beta5 integrin with internalized ROS. Control experiments showed that blocking alpha(v)beta3 function with antibodies did not inhibit ROS phagocytosis and that alpha(v)beta3 did not colocalize with phagocytosed ROS. Taken together, our results indicate that the RPE requires the integrin receptor alpha(v)beta5 specifically for the binding of ROS and that phagocytosis involves internalization of a ROS-alpha(v)beta5 complex. Alpha(v)beta5 integrin does not participate in phagocytosis by other phagocytic cells and is the first of the RPE receptors involved in ROS phagocytosis that may be specific for this process. PMID- 9371779 TI - Smad8 mediates the signaling of the ALK-2 [corrected] receptor serine kinase. AB - Smad proteins are critical intracellular mediators of signaling by growth and differentiation factors of the transforming growth factor beta superfamily. We have isolated a member of the Smad family, Smad8, from a rat brain cDNA library and biochemically and functionally characterized its ability to transduce signals from serine kinase receptors. In Xenopus embryo, Smad8 is able to transcriptionally activate a subset of mesoderm target genes similar to those induced by the receptor serine kinase, activin receptor-like kinase (ALK)-2. Smad8 can be specifically phosphorylated by a constitutively active ALK-2 but not the related receptor serine kinase, ALK-4. In response to signaling from ALK-2, Smad8 associates with a common regulatory molecule, Smad4, and this association leads to a synergistic effect on gene transcription. Furthermore, Smad8 is able to rescue the expression of mesoderm genes blocked by truncated ALK-2 in the embryo. These results indicate that Smad8 can function as a downstream signaling mediator of ALK-2. PMID- 9371780 TI - Ubiquitin-mediated regulation of 3-hydroxy-3-methylglutaryl-CoA reductase. AB - Regulation of the sterol-synthesizing mevalonate pathway occurs in part through feedback-regulated endoplasmic reticulum degradation of 3-hydroxy-3 methylglutaryl-CoA reductase (HMG-R). In yeast, the Hmg2p isozyme of HMG-R is regulated in this manner. We have tested the involvement of ubiquitination in the regulated degradation of Hmg2p, by using both genetic and direct biochemical approaches. Hmg2p degradation required the UBC7 gene, and Hmg2p protein was directly ubiquitinated. Hmg2p ubiquitination was dependent on UBC7 and was specific for the degraded yeast Hmg2p isozyme. Furthermore, Hmg2p ubiquitination was regulated by the mevalonate pathway in a manner consistent with regulation of Hmg2p stability. Thus, regulated ubiquitination appeared to be the mechanism by which Hmg2p stability is controlled in yeast. Finally, our data indicated that the feedback signal controlling Hmg2p ubiquitination and degradation was derived from farnesyl diphosphate, and thus implied conservation of an HMG-R degradation signal between yeast and mammals. PMID- 9371781 TI - In vivo functions of the Saccharomyces cerevisiae Hsp90 chaperone. AB - In the highly concentrated environment of the cell, polypeptide chains are prone to aggregation during synthesis (as nascent chains await the emergence of the remainder of their folding domain), translocation, assembly, and exposure to stresses that cause previously folded proteins to unfold. A large and diverse group of proteins, known as chaperones, transiently associate with such folding intermediates to prevent aggregation, but in many cases the specific functions of individual chaperones are still not clear. In vivo, Hsp90 (heat shock protein 90) plays a role in the maturation of components of signal transduction pathways but also exhibits chaperone activity with diverse proteins in vitro, suggesting a more general function. We used a unique temperature-sensitive mutant of Hsp90 in Saccharomyces cerevisiae, which rapidly and completely loses activity on shift to high temperatures, to examine the breadth of Hsp90 functions in vivo. The data suggest that Hsp90 is not required for the de novo folding of most proteins, but it is required for a specific subset of proteins that have greater difficulty reaching their native conformations. Under conditions of stress, Hsp90 does not generally protect proteins from thermal inactivation but does enhance the rate at which a heat-damaged protein is reactivated. Thus, although Hsp90 is one of the most abundant chaperones in the cell, its in vivo functions are highly restricted. PMID- 9371782 TI - The phosphorylation state of the FIGQY tyrosine of neurofascin determines ankyrin binding activity and patterns of cell segregation. AB - Cell-cell recognition and patterning of cell contacts have a critical role in mediating reversible assembly of a variety of transcellular complexes in the nervous system. This study provides evidence for regulation of cell interactions through modulation of ankyrin binding to neurofascin, a member of the L1CAM family of nervous system cell adhesion molecules. The phosphorylation state of the conserved FIGQY tyrosine in the cytoplasmic domain of neurofascin regulates ankyrin binding and governs neurofascin-dependent cell aggregation as well as cell sorting when neurofascin is expressed in neuroblastoma cells. These findings suggest a general mechanism for the patterning of cell contact based on external signals that regulate tyrosine phosphorylation of L1CAM members and modulate their binding to ankyrin. PMID- 9371783 TI - Genghis Khan (Gek) as a putative effector for Drosophila Cdc42 and regulator of actin polymerization. AB - The small GTPases Cdc42 and Rac regulate a variety of biological processes, including actin polymerization, cell proliferation, and JNK/mitogen-activated protein kinase activation, conceivably via distinct effectors. Whereas the effector for mitogen-activated protein kinase activation appears to be p65PAK, the identity of effector(s) for actin polymerization remains unclear. We have found a putative effector for Drosophila Cdc42, Genghis Khan (Gek), which binds to Dcdc42 in a GTP-dependent and effector domain-dependent manner. Gek contains a predicted serine/threonine kinase catalytic domain that is 63% identical to human myotonic dystrophy protein kinase and has protein kinase activities. It also possesses a large coiled-coil domain, a putative phorbol ester binding domain, a pleckstrin homology domain, and a Cdc42 binding consensus sequence that is required for its binding to Dcdc42. To study the in vivo function of gek, we generated mutations in the Drosophila gek locus. Egg chambers homozygous for gek mutations exhibit abnormal accumulation of F-actin and are defective in producing fertilized eggs. These phenotypes can be rescued by a wild-type gek transgene. Our results suggest that this multidomain protein kinase is an effector for the regulation of actin polymerization by Cdc42. PMID- 9371784 TI - Erythrocyte membrane vesiculation: model for the molecular mechanism of protein sorting. AB - Budding and vesiculation of erythrocyte membranes occurs by a process involving an uncoupling of the membrane skeleton from the lipid bilayer. Vesicle formation provides an important means whereby protein sorting and trafficking can occur. To understand the mechanism of sorting at the molecular level, we have developed a micropipette technique to quantify the redistribution of fluorescently labeled erythrocyte membrane components during mechanically induced membrane deformation and vesiculation. Our previous studies indicated that the spectrin-based membrane skeleton deforms elastically, producing a constant density gradient during deformation. Our current studies showed that during vesiculation the skeleton did not fragment but rather retracted to the cell body, resulting in a vesicle completely depleted of skeleton. These local changes in skeletal density regulated the sorting of nonskeletal membrane components. Highly mobile membrane components, phosphatidylethanolamine- and glycosylphosphatidylinositol-linked CD59 with no specific skeletal association were enriched in the vesicle. In contrast, two components with known specific skeletal association, band 3 and glycophorin A, were differentially depleted in vesicles. Increasing the skeletal association of glycophorin A by liganding its extrafacial domain reduced the fraction partitioning to the vesicle. We conclude that this technique of bilayer/skeleton uncoupling provides a means with which to study protein sorting driven by changes in local skeletal density. Moreover, it is the interaction of particular membrane components with the spectrin-based skeleton that determines molecular partitioning during protein sorting. PMID- 9371785 TI - Coordinate regulation of lipogenic gene expression by androgens: evidence for a cascade mechanism involving sterol regulatory element binding proteins. AB - To gain more insight into the molecular mechanisms by which androgens stimulate lipogenesis and induce a marked accumulation of neutral lipids in the human prostate cancer cell line LNCaP, we studied their impact on the expression of lipogenic enzymes. Northern blot analysis of the steady-state mRNA levels of seven different lipogenic enzymes revealed that androgens coordinately stimulate the expression of enzymes belonging to the two major lipogenic pathways: fatty acid synthesis and cholesterol synthesis. In view of the important role of the recently characterized sterol regulatory element binding proteins (SREBPs) in the coordinate induction of lipogenic genes, we examined whether the observed effects of androgens on lipogenic gene expression are mediated by these transcription factors. Our findings indicate that androgens stimulate the expression of SREBP transcripts and precursor proteins and enhance the nuclear content of the mature active form of the transcription factor. Moreover, by using the fatty acid synthase gene as an experimental paradigm we demonstrate that the presence of an SREBP-binding site is essential for its regulation by androgens. These data support the hypothesis that SREBPs are involved in the coordinate regulation of lipogenic gene expression by androgens and provide evidence for the existence of a cascade mechanism of androgen-regulated gene expression. PMID- 9371786 TI - Identification of a family of low-affinity insulin-like growth factor binding proteins (IGFBPs): characterization of connective tissue growth factor as a member of the IGFBP superfamily. AB - The insulin-like growth factor (IGF) binding proteins (IGFBPs) modulate the actions of the insulin-like growth factors in endocrine, paracrine, and autocrine settings. Additionally, some IGFBPs appear to exhibit biological effects that are IGF independent. The six high-affinity IGFBPs that have been characterized to date exhibit 40-60% amino acid sequence identity overall, with the most conserved sequences in their NH2 and COOH termini. We have recently demonstrated that the product of the mac25/IGFBP-7 gene, which shows significant conservation in the NH2 terminus, including an "IGFBP motif' (GCGCCXXC), exhibits low-affinity IGF binding. The closely related mammalian genes connective tissue growth factor (CTGF) gene, nov, and cyr61 encode secreted proteins that also contain the conserved sequences and IGFBP motifs in their NH2 termini. To ascertain if these genes, along with mac25/IGFBP-7, encode a family of low-affinity IGFBPs, we assessed the IGF binding characteristics of recombinant human CTGF (rhCTGF). The ability of baculovirus-synthesized rhCTGF to bind IGFs was demonstrated by Western ligand blotting, affinity cross-linking, and competitive affinity binding assays using 125I-labeled IGF-I or IGF-II and unlabeled IGFs. CTGF, like mac25/IGFBP-7, specifically binds IGFs, although with relatively low affinity. On the basis of these data, we propose that CTGF represents another member of the IGFBP family (IGFBP-8) and that the CTGF gene, mac25/IGFBP-7, nov, and cyr61 are members of a family of low-affinity IGFBP genes. These genes, along with those encoding the high-affinity IGFBPs 1-6, together constitute an IGFBP superfamily whose products function in IGF-dependent or IGF-independent modes to regulate normal and neoplastic cell growth. PMID- 9371787 TI - Ol-Prx 3, a member of an additional class of homeobox genes, is unimodally expressed in several domains of the developing and adult central nervous system of the medaka (Oryzias latipes). AB - Large-scale genetic screens for mutations affecting early neurogenesis of vertebrates have recently been performed with an aquarium fish, the zebrafish. Later stages of neural morphogenesis have attracted less attention in small fish species, partly because of the lack of molecular markers of developing structures that may facilitate the detection of discrete structural alterations. In this context, we report the characterization of Ol-Prx 3 (Oryzias latipes-Prx 3). This gene was isolated in the course of a large-scale screen for brain cDNAs containing a highly conserved DNA binding region, the homeobox helix-three. Sequence analysis revealed that this gene belongs to another class of homeobox genes, together with a previously isolated mouse ortholog, called OG-12 [Rovescalli, A. C., Asoh, S. & Nirenberg, M. (1996) Proc. Natl. Acad. Sci. USA 93, 10691-10696] and with the human SHOX gene [Rao, E., Weiss, B., Fukami, M., Rump, A., Niesler, B., et al. (1997) Nat. Genet. 16, 54-62], thought to be involved in the short-stature phenotype of Turner syndrome patients. These three genes exhibit a moderate level of identity in the homeobox with the other genes of the paired-related (PRX) gene family. Ol-Prx 3, as well as the PRX genes, are expressed in various cartilaginous structures of head and limbs. These genes might thus be involved in common regulatory pathways during the morphogenesis of these structures. Moreover, this paper reports a complex and monophasic pattern of Ol-Prx 3 expression in the central nervous system, which differs markedly from the patterns reported for the PRX genes, Prx 3 excluded: this gene begins to be expressed in a variety of central nervous system territories at late neurula stage. Strikingly, it remains turned on in some of the derivatives of each territory during the entire life of the fish. We hope this work will thus help identify common features for the PRX 3 family of homeobox genes. PMID- 9371788 TI - Homeobox gene Prx3 expression in rodent brain and extraneural tissues. AB - Different cDNA clones encoding a rat homeobox gene and the mouse homologue OG-12 were cloned from adult rat brain and mouse embryo mRNA, respectively. The predicted amino acid sequences of the proteins belong to the paired-related subfamily of homeodomain proteins (Prx homeodomains). Hence, the gene was named Prx3 and the mouse and rat genes are indicated as mPrx3 and rPrx3, respectively. In the mouse as well as in the rat, the predicted Prx3 proteins share the homeodomain but have three different N termini, a 12-aa residue variation in the C terminus, and contain a 14-aa residue motif common to a subset of homeodomain proteins, termed the "aristaless domain." Genetic mapping of Prx3 in the mouse placed this gene on chromosome 3. In situ hybridization on whole mount 12.5-day old mouse embryos and sections of rat embryos at 14.5 and 16.5 days postcoitum revealed marked neural expression in discrete regions in the lateral and medial geniculate complex, superior and inferior colliculus, the superficial gray layer of the superior colliculus, pontine reticular formation, and inferior olive. In rat and mouse embryos, nonneuronal structures around the oral cavity and in hip and shoulder regions also expressed the Prx3 gene. In the adult rat brain, Prx3 gene expression was restricted to thalamic, tectal, and brainstem structures that include relay nuclei of the visual and auditory systems as well as other ascending systems conveying somatosensory information. Prx3 may have a role in specifying neural systems involved in processing somatosensory information, as well as in face and body structure formation. PMID- 9371789 TI - Genes regulated by androgen in the rat ventral prostate. AB - Genes that are regulated by androgen in the prostate were studied in the rat. Four of the less than 10 genes that are down-regulated by androgen in the ventral prostate of a 7-day castrated rat were identified; their mRNAs decayed with identical kinetics. Twenty-five of the estimated 56 genes that are up-regulated by androgen in the castrated prostate have been isolated. The up-regulated genes fall into two kinetic types. Early genes are significantly up-regulated by 6.5 hr whereas the delayed genes respond mainly after 24 hr from the time of androgen replacement. These androgen-response genes are also regulated in the prostate by castration, indicating that these genes could play important roles in androgen induced regrowth and/or castration-induced regression of the prostate during hormonal manipulation. A survey of the tissue specificity showed that the androgen-response gene expression program in the prostate is mainly prostate specific. Total RNA Northern blot analysis detects the expression of about 16 up regulated genes and 3 down-regulated genes in the prostate only. Four up regulated genes and one down-regulated gene are regulated by androgen in both the prostate and seminal vesicles but not in other organs. The expression of the remaining androgen-response genes is not limited to the prostate but is only responsive to androgen in the prostate. This survey of the androgen-response gene expression program provides insights into the molecular and cellular mechanisms of androgen action in the prostate. PMID- 9371790 TI - The N terminus of the Drosophila Numb protein directs membrane association and actin-dependent asymmetric localization. AB - Drosophila Numb is a membrane associated protein of 557 amino acids (aa) that localizes asymmetrically into a cortical crescent in mitotic neural precursor cells and segregates into one of the daughter cells, where it is required for correct cell fate specification. We demonstrate here that asymmetric localization but not membrane localization of Numb in Drosophila embryos is inhibited by latrunculin A, an inhibitor of actin assembly. We also show that deletion of either the first 41 aa or aa 41-118 of Numb eliminates both localization to the cell membrane and asymmetric localization during mitosis, whereas C-terminal deletions or deletions of central portions of Numb do not affect its subcellular localization. Fusion of the first 76 or the first 119 aa of Numb to beta galactosidase results in a fusion protein that localizes to the cell membrane, but fails to localize asymmetrically during mitosis. In contrast, a fusion protein containing the first 227 aa of Numb and beta-galactosidase localizes asymmetrically during mitosis and segregates into the same daughter cell as the endogenous Numb protein, demonstrating that the first 227 aa of the Numb protein are sufficient for asymmetric localization. PMID- 9371791 TI - The role of thyroid hormone in zebrafish and axolotl development. AB - Exogenous thyroid hormone (TH) induces premature differentiation of the zebrafish pectoral fins, which are analogous to the forelimbs of tetrapods. It accelerates the growth of the pelvic fins but not precociously. Goitrogens, which are chemical inhibitors of TH synthesis by the thyroid gland, inhibit the transition from larva to juvenile fish including the formation of scales, and pigment pattern; they stunt the growth of both pectoral and pelvic paired fins. Inhibition by goitrogens is rescued by the simultaneous addition of thyroxine. The effect of adding TH to the rearing water of the postembryonic Mexican axolotl was reinvestigated under conditions that permit continued growth and development. In addition to morphological changes that have been described, TH greatly stimulates axolotl limb growth causing the resulting larva to be proportioned as an adult in about two months. This study extends the known evolutionary relatedness of tetrapod limbs and fish fins to include the TH stimulation of salamander limb and zebrafish fin growth, and suggests that TH is required to complete the life cycle of a typical bony fish and a salamander at the same developmental stage that it controls anuran and flounder metamorphosis. PMID- 9371792 TI - Siamois is required for formation of Spemann's organizer. AB - Spemann's organizer develops in response to dorsal determinants that act via maternal components of the wnt pathway. The function of siamois, a wnt-inducible homeobox gene, in Spemann's organizer development was examined by fusion of defined transcriptional regulatory domains to the siamois homeodomain. Similar to native siamois, a VP16 activator fusion induced axis formation, indicating that siamois functions as a transcriptional activator in axis induction. Fusion of the engrailed repressor generated a dominant inhibitor that blocked axis induction by Xwnt8, beta-catenin, and siamois, and repressed wnt activation of the goosecoid promoter. Dorsal injection of the engrailed-siamois fusion resulted in complete inhibition of dorsal development and organizer gene expression, an effect rescued by siamois, but not by Xwnt8 or beta-catenin. Thus, as a zygotic mediator of maternal dorsal signals, siamois function is required for development of Spemann's organizer. PMID- 9371793 TI - Primate species richness is determined by plant productivity: implications for conservation. AB - The explanation of patterns in species richness ranks among the most important tasks of ecology. Current theories emphasize the interaction between historical and geographical factors affecting the size of the regional species pool and of locally acting processes such as competitive exclusion, disturbance, productivity, and seasonality. Local species richness, or alpha diversity, of plants and primary consumers has been claimed to peak in habitats of low and intermediate productivity, which, if true, has major implications for conservation. Here, by contrast, we show that local richness of Neotropical primates (platyrrhines) is influenced by both historical biogeography and productivity but not by tree species richness or seasonality. This pattern indicates that habitats with the highest plant productivity are also the richest for many important primary consumers. We show further that fragmentation of Amazonian rain forests in the Pleistocene, if it occurred, appears to have had a negligible influence on primate alpha species richness. PMID- 9371794 TI - Determining divergence times with a protein clock: update and reevaluation. AB - A recent study of the divergence times of the major groups of organisms as gauged by amino acid sequence comparison has been expanded and the data have been reanalyzed with a distance measure that corrects for both constraints on amino acid interchange and variation in substitution rate at different sites. Beyond that, the availability of complete genome sequences for several eubacteria and an archaebacterium has had a great impact on the interpretation of certain aspects of the data. Thus, the majority of the archaebacterial sequences are not consistent with currently accepted views of the Tree of Life which cluster the archaebacteria with eukaryotes. Instead, they are either outliers or mixed in with eubacterial orthologs. The simplest resolution of the problem is to postulate that many of these sequences were carried into eukaryotes by early eubacterial endosymbionts about 2 billion years ago, only very shortly after or even coincident with the divergence of eukaryotes and archaebacteria. The strong resemblances of these same enzymes among the major eubacterial groups suggest that the cyanobacteria and Gram-positive and Gram-negative eubacteria also diverged at about this same time, whereas the much greater differences between archaebacterial and eubacterial sequences indicate these two groups may have diverged between 3 and 4 billion years ago. PMID- 9371795 TI - Rapid decline of fitness in panmictic populations of Drosophila melanogaster maintained under relaxed natural selection. AB - The parameters of the spontaneous deleterious mutation process remain poorly known, despite their importance. Here, we report the results of a mutation accumulation experiment performed on panmictic populations of Drosophila melanogaster without any genetic manipulations. Two experimental populations were kept for 30 generations under relaxed natural selection. Each generation, 100 pairs were formed randomly, and every fecund pair contributed a son and a daughter to the next generation. Comparison with two controls, one cryopreserved and the other kept as the experimental populations but with long generation time, showed that the number of surviving offspring per female declined by 0.2% and 2.0% per generation under benign and harsh, competitive conditions, respectively. Thus, the mutational pressure on fitness may be strong and depends critically on the conditions under which fitness is assayed. PMID- 9371796 TI - Plasmodium falciparum antigenic diversity: evidence of clonal population structure. AB - Plasmodium falciparum, the agent of malignant malaria, is one of mankind's most severe scourges. Efforts to develop preventive vaccines or remedial drugs are handicapped by the parasite's rapid evolution of drug resistance and protective antigens. We examine 25 DNA sequences of the gene coding for the highly polymorphic antigenic circumsporozoite protein. We observe total absence of silent nucleotide variation in the two nonrepeated regions of the gene. We propose that this absence reflects a recent origin (within several thousand years) of the world populations of P. falciparum from a single individual; the amino acid polymorphisms observed in these nonrepeat regions would result from strong natural selection. Analysis of these polymorphisms indicates that: (i) the incidence of recombination events does not increase with nucleotide distance; (ii) the strength of linkage disequilibrium between nucleotides is also independent of distance; and (iii) haplotypes in the two nonrepeat regions are correlated with one another, but not with the central repeat region they span. We propose two hypotheses: (i) variation in the highly polymorphic central repeat region arises by mitotic intragenic recombination, and (ii) the population structure of P. falciparum is clonal--a state of affairs that persists in spite of the necessary stage of physiological sexuality that the parasite must sustain in the mosquito vector to complete its life cycle. PMID- 9371797 TI - A gene-culture coevolutionary model for brother-sister mating. AB - We present a gene-culture coevolutionary model for brother-sister mating in the human. It is shown that cultural--as opposed to innate--determination of mate preference may evolve, provided the inbreeding depression is sufficiently high. At this coevolutionary equilibrium, sib mating is avoided because of cultural pressures. PMID- 9371799 TI - Yeast microarrays for genome wide parallel genetic and gene expression analysis. AB - We have developed high-density DNA microarrays of yeast ORFs. These microarrays can monitor hybridization to ORFs for applications such as quantitative differential gene expression analysis and screening for sequence polymorphisms. Automated scripts retrieved sequence information from public databases to locate predicted ORFs and select appropriate primers for amplification. The primers were used to amplify yeast ORFs in 96-well plates, and the resulting products were arrayed using an automated micro arraying device. Arrays containing up to 2,479 yeast ORFs were printed on a single slide. The hybridization of fluorescently labeled samples to the array were detected and quantitated with a laser confocal scanning microscope. Applications of the microarrays are shown for genetic and gene expression analysis at the whole genome level. PMID- 9371798 TI - Sequence variation in the Fanconi anemia gene FAA. AB - Fanconi anemia (FA) is a genetically heterogeneous autosomal recessive syndrome associated with chromosomal instability, hypersensitivity to DNA crosslinking agents, and predisposition to malignancy. The gene for FA complementation group A (FAA) recently has been cloned. The cDNA is predicted to encode a polypeptide of 1,455 amino acids, with no homologies to any known protein that might suggest a function for FAA. We have used single-strand conformational polymorphism analysis to screen genomic DNA from a panel of 97 racially and ethnically diverse FA patients from the International Fanconi Anemia Registry for mutations in the FAA gene. A total of 85 variant bands were detected. Forty-five of the variants are probably benign polymorphisms, of which nine are common and can be used for various applications, including mapping studies for other genes in this region of chromosome 16q. Amplification refractory mutation system assays were developed to simplify their detection. Forty variants are likely to be pathogenic mutations. Seventeen of these are microdeletions/microinsertions associated with short direct repeats or homonucleotide tracts, a type of mutation thought to be generated by a mechanism of slipped-strand mispairing during DNA replication. A screening of 350 FA probands from the International Fanconi Anemia Registry for two of these deletions (1115-1118del and 3788-3790del) revealed that they are carried on about 2% and 5% of the FA alleles, respectively. 3788-3790del appears in a variety of ethnic groups and is found on at least two different haplotypes. We suggest that FAA is hypermutable, and that slipped-strand mispairing, a mutational mechanism recognized as important for the generation of germ-line and somatic mutations in a variety of cancer-related genes, including p53, APC, RB1, WT1, and BRCA1, may be a major mechanism for FAA mutagenesis. PMID- 9371800 TI - Analysis of a peptide hormone-receptor interaction in the yeast two-hybrid system. AB - Interaction between a peptide hormone and extracellular domains of its receptor is a crucial step for initiation of hormone action. We have developed a modification of the yeast two-hybrid system to study this interaction and have used it to characterize the interaction of insulin-like growth factor 1 (IGF-1) with its receptor by using GAL4 transcriptional regulation with a beta galactosidase assay as readout. In this system, IGF-1 and proIGF-1 bound to the cysteine-rich domain, extracellular domain, or entire IGF-1 proreceptor. This interaction was specific. Thus, proinsulin showed no significant interaction with the IGF-1 receptor, while a chimeric proinsulin containing the C-peptide of IGF-1 had an intermediate interaction, consistent with its affinity for the IGF-1 receptor. Over 2000 IGF-1 mutants were generated by PCR and screened for interaction with the color assay. About 40% showed a strong interaction, 20% showed an intermediate interaction, and 40% give little or no signal. Of 50 mutants that were sequenced, several (Leu-5 --> His, Glu-9 --> Val, Arg-37 --> Gly, and Met-59 --> Leu) appeared to enhance receptor association, others resulted in weaker receptor interaction (Tyr-31 --> Phe and Ile-43 --> Phe), and two gave no detectable signal (Leu-14 --> Arg and Glu-46 --> Ala). Using PCR based mutagenesis with proinsulin, we also identified a gain of function mutant (proinsulin Leu-17 --> Pro) that allowed for a strong IGF-1-receptor interaction. These data demonstrate that the specificity of the interaction between a hormone and its receptor can be characterized with high efficiency in the two-hybrid system and that novel hormone analogues may be found by this method. PMID- 9371801 TI - The Tabby phenotype is caused by mutation in a mouse homologue of the EDA gene that reveals novel mouse and human exons and encodes a protein (ectodysplasin-A) with collagenous domains. AB - Mouse Tabby (Ta) and X chromosome-linked human EDA share the features of hypoplastic hair, teeth, and eccrine sweat glands. We have cloned the Ta gene and find it to be homologous to the EDA gene. The gene is altered in two Ta alleles with a point mutation or a deletion. The gene is expressed in developing teeth and epidermis; no expression is seen in corresponding tissues from Ta mice. Ta and EDA genes both encode alternatively spliced forms; novel exons now extend the 3' end of the EDA gene. All transcripts recovered have the same 5' exon. The longest Ta cDNA encodes a 391-residue transmembrane protein, ectodysplasin-A, containing 19 Gly-Xaa-Yaa repeats. The isoforms of ectodysplasin-A may correlate with differential roles during embryonic development. PMID- 9371802 TI - Multiple protein domains determine the cell type-specific nuclear distribution of the catalytic subunit required for apolipoprotein B mRNA editing. AB - Apolipoprotein B (apoB) mRNA editing catalyzed by apoB mRNA editing catalytic subunit 1 (APOBEC-1) has been proposed to be a nuclear process. To test this hypothesis, the subcellular distribution of hemagglutinin- (HA) tagged APOBEC-1 expressed in transiently transfected hepatoma cells was determined by indirect immunofluorescence microscopy. HA-APOBEC-1 was detected in both the nucleus and cytoplasm of rat and human hepatoma cells. Mutagenesis of APOBEC-1 demonstrated that the N-terminal 56 amino acids (1-56) were necessary for the nuclear distribution of APOBEC-1, but this region did not contain a functional nuclear localization signal (NLS). However, we identified a 24-amino acid domain in the C terminus of APOBEC-1 with characteristics of a cytoplasmic retention signal (CRS) or a nuclear export signal (NES). These data suggest, therefore, that the nuclear import of APOBEC-1 may not be mediated by a positive NLS; rather, it may be achieved by overcoming the effect of a CRS/NES. We also demonstrated that the nuclear distribution of APOBEC-1 occurred only in cell lines that were capable of editing apoB RNA. We propose that the cellular distribution of APOBEC-1 is determined by multiple domains within this protein, and a nuclear localization of the enzyme may be regulated by cell type-specific factors that render these cells uniquely editing competent. PMID- 9371803 TI - The yeast Cac1 protein is required for the stable inheritance of transcriptionally repressed chromatin at telomeres. AB - Cac1p is a subunit of yeast chromatin assembly factor I (yCAF-I) that is thought to assemble nucleosomes containing diacetylated histones onto newly replicated DNA [Kaufman, P. D., Kobayashi, R. & Stillman, B. (1997) Genes Dev. 11, 345-357]. Although cac1 delta cells could establish and maintain transcriptional repression at telomeres, they displayed a reduced heritability of the repressed state. Single-cell analysis revealed that individual cac1 delta cells switch from transcriptionally "off" to transcriptionally "on" more often per cell cycle than wild-type cells. In addition, cac1 delta cells were defective for transcriptional silencing near internal tracts of C(1-3)A sequence, but they showed no defect in silencing at the silent mating type loci when analyzed by a reverse transcription PCR assay. Despite the loss of transcriptional silencing at telomeres and internal C(1-3)A tracts, subtelomeric DNA was organized into nucleosomes that had all of the features characteristic of silent chromatin, such as hypoacetylation of histone H4 and protection from methylation by the Escherichia coli dam methylase. Thus, these features of silent chromatin are not sufficient for stable maintenance of a silent chromatin state. We propose that the inheritance of the transcriptionally repressed state requires the specific pattern of histone acetylation conferred by yCAF-I-mediated nucleosome assembly. PMID- 9371804 TI - Base excision repair deficient mice lacking the Aag alkyladenine DNA glycosylase. AB - 3-methyladenine (3MeA) DNA glycosylases remove 3MeAs from alkylated DNA to initiate the base excision repair pathway. Here we report the generation of mice deficient in the 3MeA DNA glycosylase encoded by the Aag (Mpg) gene. Alkyladenine DNA glycosylase turns out to be the major DNA glycosylase not only for the cytotoxic 3MeA DNA lesion, but also for the mutagenic 1,N6-ethenoadenine (epsilonA) and hypoxanthine lesions. Aag appears to be the only 3MeA and hypoxanthine DNA glycosylase in liver, testes, kidney, and lung, and the only epsilonA DNA glycosylase in liver, testes, and kidney; another epsilonA DNA glycosylase may be expressed in lung. Although alkyladenine DNA glycosylase has the capacity to remove 8-oxoguanine DNA lesions, it does not appear to be the major glycosylase for 8-oxoguanine repair. Fibroblasts derived from Aag -/- mice are alkylation sensitive, indicating that Aag -/- mice may be similarly sensitive. PMID- 9371805 TI - All cyclophilins and FK506 binding proteins are, individually and collectively, dispensable for viability in Saccharomyces cerevisiae. AB - The cyclophilins and FK506 binding proteins (FKBPs) bind to cyclosporin A, FK506, and rapamycin and mediate their immunosuppressive and toxic effects, but the physiological functions of these proteins are largely unknown. Cyclophilins and FKBPs are ubiquitous and highly conserved enzymes that catalyze peptidyl-prolyl isomerization, a rate-limiting step during in vitro protein folding. We have addressed their functions by a genetic approach in the yeast Saccharomyces cerevisiae. Five cyclophilins and three FKBPs previously were identified in yeast. We identified four additional enzymes: Cpr6 and Cpr7, which are homologs of mammalian cyclophilin 40 that have also recently been independently isolated by others, Cpr8, a homolog of the secretory pathway cyclophilin Cpr4, and Fpr4, a homolog of the nucleolar FKBP, Fpr3. None of the eight cyclophilins or four FKBPs were essential. Surprisingly, yeast mutants lacking all 12 immunophilins were viable, and the phenotype of the dodecuplet mutant resulted from simple addition of the subtle phenotypes of each individual mutation. We conclude that cyclophilins and FKBPs do not play an essential general role in protein folding and find little evidence of functional overlap between the different enzymes. We propose that each cyclophilin and FKBP instead regulates a restricted number of unique partner proteins that remain to be identified. PMID- 9371807 TI - Molecular characterization of four induced alleles at the Ednrb locus. AB - The piebald locus on mouse chromosome 14 encodes the endothelin-B receptor (EDNRB), a G protein-coupled, seven-transmembrane domain protein, which is required for neural crest-derived melanocyte and enteric neuron development. A spontaneous null allele of Ednrb results in homozygous mice that are predominantly white and die as juveniles from megacolon. To identify the important domains for EDNRB function, four recessive juvenile lethal alleles created by either radiation or chemical mutagens (Ednrb27Pub, Ednrb17FrS, Ednrb1Chlc, and Ednrb3Chlo) were examined at the molecular level. Ednrb27Pub mice harbor a mutation at a critical proline residue in the fifth transmembrane domain of the EDNRB protein. A gross genomic alteration within the Ednrb gene in Ednrb3Chlo results in the production of aberrantly sized transcripts and no authentic Ednrb mRNA. Ednrb17FrS mice exhibited a decreased level of Ednrb mRNA, supporting previous observations that the degree of spotting in piebald mice is dependent on the amount of EDNRB expressed. Finally, no molecular defect was detected in Ednrb1Chlc mice, which produce normal levels of Ednrb mRNA in adult brain, suggesting that the mutation affects important regulatory elements that mediate the expression of the gene during development. PMID- 9371806 TI - A network of interacting transcriptional regulators involved in Drosophila neural fate specification revealed by the yeast two-hybrid system. AB - Neural fate specification in Drosophila is promoted by the products of the proneural genes, such as those of the achaete-scute complex, and antagonized by the products of the Enhancer of split [E(spl)] complex, hairy, and extramacrochaetae. As all these proteins bear a helix-loop-helix (HLH) dimerization domain, we investigated their potential pairwise interactions using the yeast two-hybrid system. The fidelity of the system was established by its ability to closely reproduce the already documented interactions among Da, Ac, Sc, and Extramacrochaetae. We show that the seven E(spl) basic HLH proteins can form homo- and heterodimers inter-se with distinct preferences. We further show that a subset of E(spl) proteins can heterodimerize with Da, another subset can heterodimerize with proneural proteins, and yet another with both, indicating specialization within the E(spl) family. Hairy displays no interactions with any of the HLH proteins tested. It does interact with the non-HLH protein Groucho, which itself interacts with all E(spl) basic HLH proteins, but with none of the proneural proteins or Da. We investigated the structural requirements for some of these interactions by site-specific and deletion mutagenesis. PMID- 9371808 TI - TnTIN and TnTAP: mini-transposons for site-specific proteolysis in vivo. AB - Tobacco etch virus (TEV) protease recognizes a 7-aa consensus sequence, Glu-Xaa Xaa-Tyr-Xaa-Gln-Ser, where Xaa can be almost any amino acyl residue. Cleavage occurs between the conserved Gln and Ser residues. Because of its distinct specificity, TEV protease can be expressed in the cytoplasm without interfering with viability. Polypeptides that are not natural substrates of TEV protease are proteolyzed if they carry the appropriate cleavage site. Thus, this protease can be used to study target proteins in their natural environment in vivo, as well as in vitro. We describe two TnS-based mini-transposons that insert TEV protease cleavage sites at random into target proteins. TnTIN introduces TEV cleavage sites into cytoplasmic proteins. TnTAP facilitates the same operation for proteins localized to the bacterial cell envelope. By using two different target proteins, SecA and TolC, we show that such modified proteins can be cleaved in vivo and in vitro by TEV protease. Possible applications of the site-specific proteolysis approach are topological studies of soluble as well as of inner and outer membrane proteins, protein inactivation, insertion mutagenesis experiments, and protein tagging. PMID- 9371809 TI - Direct repeat sequences in the Streptomyces chitinase-63 promoter direct both glucose repression and chitin induction. AB - The chi63 promoter directs glucose-sensitive, chitin-dependent transcription of a gene involved in the utilization of chitin as carbon source. Analysis of 5' and 3' deletions of the promoter region revealed that a 350-bp segment is sufficient for wild-type levels of expression and regulation. The analysis of single base changes throughout the promoter region, introduced by random and site-directed mutagenesis, identified several sequences to be important for activity and regulation. Single base changes at -10, -12, -32, -33, -35, and -37 upstream of the transcription start site resulted in loss of activity from the promoter, suggesting that bases in these positions are important for RNA polymerase interaction. The sequences centered around -10 (TATTCT) and -35 (TTGACC) in this promoter are, in fact, prototypical of eubacterial promoters. Overlapping the RNA polymerase binding site is a perfect 12-bp direct repeat sequence. Some base changes within this direct repeat resulted in constitutive expression, suggesting that this sequence is an operator for negative regulation. Other base changes resulted in loss of glucose repression while retaining the requirement for chitin induction, suggesting that this sequence is also involved in glucose repression. The fact that cis-acting mutations resulted in glucose resistance but not inducer independence rules out the possibility that glucose repression acts exclusively by inducer exclusion. The fact that mutations that affect glucose repression and chitin induction fall within the same direct repeat sequence module suggests that the direct repeat sequence facilitates both chitin induction and glucose repression. PMID- 9371810 TI - Recombination-dependent deletion formation in mammalian cells deficient in the nucleotide excision repair gene ERCC1. AB - Nucleotide excision repair proteins have been implicated in genetic recombination by experiments in Saccharomyces cerevisiae and Drosophila melanogaster, but their role, if any, in mammalian cells is undefined. To investigate the role of the nucleotide excision repair gene ERCC1, the hamster homologue to the S. cerevisiae RADIO gene, we disabled the gene by targeted knockout. Partial tandem duplications of the adenine phosphoribosyltransferase (APRT) gene then were constructed at the endogenous APRT locus in ERCC1- and ERCC1+ cells. To detect the full spectrum of gene-altering events, we used a loss-of-function assay in which the parental APRT+ tandem duplication could give rise to APRT- cells by homologous recombination, gene rearrangement, or point mutation. Measurement of rates and analysis of individual APRT- products indicated that gene rearrangements (principally deletions) were increased at least 50-fold, whereas homologous recombination was affected little. The formation of deletions is not caused by a general effect of the ERCC1 deficiency on gene stability, because ERCC1- cell lines with a single wild-type copy of the APRT gene yielded no increase in deletions. Thus, deletion formation is dependent on the tandem duplication, and presumably the process of homologous recombination. Recombination-dependent deletion formation in ERCC1- cells is supported by a significant decrease in a particular class of crossover products that are thought to arise by repair of a heteroduplex intermediate in recombination. We suggest that the ERCC1 gene product in mammalian cells is involved in the processing of heteroduplex intermediates in recombination and that the misprocessed intermediates in ERCC1- cells are repaired by illegitimate recombination. PMID- 9371811 TI - Genetically targeted cell disruption in Caenorhabditis elegans. AB - The elimination of identified cells is a powerful tool for investigating development and system function. Here we report on genetically mediated cell disruption effected by the toxic Caenorhabditis elegans mec-4(d) allele. We found that ectopic expression of mec-4(d) in the nematode causes dysfunction of a wide range of nerve, muscle, and hypodermal cells. mec-4(d)-mediated toxicity is dependent on the activity of a second gene, mec-6, rendering cell disruption conditionally dependent on genetic background. We describe a set of mec-4(d) vectors that facilitate construction of cell-specific disruption reagents and note that genetic cell disruption can be used for functional analyses of specific neurons or neuronal classes, for confirmation of neuronal circuitry, for generation of nematode populations lacking defined classes of functional cells, and for genetic screens. We suggest that mec-4(d) and/or related genes may be effective general tools for cell inactivation that could be used toward similar purposes in higher organisms. PMID- 9371812 TI - Preassembly of interleukin 2 (IL-2) receptor subunits on resting Kit 225 K6 T cells and their modulation by IL-2, IL-7, and IL-15: a fluorescence resonance energy transfer study. AB - Assembly and mutual proximities of alpha, beta, and gamma(c) subunits of the interleukin 2 receptors (IL-2R) in plasma membranes of Kit 225 K6 T lymphoma cells were investigated by fluorescence resonance energy transfer (FRET) using fluorescein isothiocyanate- and Cy3-conjugated monoclonal antibodies (mAbs) that were directed against the IL-2R alpha, IL-2R beta, and gamma(c) subunits of IL 2R. The cell-surface distribution of subunits was analyzed at the nanometer scale (2-10 nm) by FRET on a cell-by-cell basis. The cells were probed in resting phase and after coculture with saturating concentrations of IL-2, IL-7, and IL-15. FRET data from donor- and acceptor-labeled IL-2R beta-alpha, gamma-alpha, and gamma beta pairs demonstrated close proximity of all subunits to each other in the plasma membrane of resting T cells. These mutual proximities do not appear to represent mAb-induced microaggregation, because FRET measurements with Fab fragments of the mAbs gave similar results. The relative proximities were meaningfully modulated by binding of IL-2, IL-7, and IL-15. Based on FRET analysis the topology of the three subunits at the surface of resting cells can be best described by a "triangular model" in the absence of added interleukins. IL-2 strengthens the bridges between the subunits, making the triangle more compact. IL-7 and IL-15 act in the opposite direction by opening the triangle possibly because they associate their private specific alpha receptors with the beta and/or gamma(c) subunits of the IL-2R complex. These data suggest that IL-2R subunits are already colocalized in resting T cells and do not require cytokine induced redistribution. This colocalization is significantly modulated by binding of relevant interleukins in a cytokine-specific manner. PMID- 9371813 TI - Natural killer cell lines kill autologous beta2-microglobulin-deficient melanoma cells: implications for cancer immunotherapy. AB - Cancer vaccines used to generate specific cytotoxic T lymphocytes are not effective against tumor cells that have lost or suppressed expression of their class I major histocompatibility complex proteins. This loss is common in some cancers and particularly in metastatic lesions. We show that beta2-microglobulin deficient class I-negative melanoma variants derived from patients undergoing specific T cell therapy are lysed by heterologous as well as autologous natural killer (NK) lines and clones, but not by specific T cells. Moreover, the minor NK cell fraction but not the major T cell fraction derived from heterologous lymphokine activated killer cells kills those tumor cell lines. ICAM-1 expression by the different class I protein deficient tumors was correlated with their sensitivity to lysis by NK cells. Adoptive autologous NK therapy may be an important supplement to consider in the design of new cancer immunotherapies. PMID- 9371814 TI - Heat shock fusion proteins as vehicles for antigen delivery into the major histocompatibility complex class I presentation pathway. AB - Mice immunized with heat shock proteins (hsps) isolated from mouse tumor cells (donor cells) produce CD8 cytotoxic T lymphocytes (CTL) that recognize donor cell peptides in association with the major histocompatibility complex (MHC) class I proteins of the responding mouse. The CTL are induced apparently because peptides noncovalently associated with the isolated hsp molecules can enter the MHC class I antigen processing pathway of professional antigen-presenting cells. Using a recombinant heat shock fusion protein with a large fragment of ovalbumin covalently linked to mycobacterial hsp70, we show here that when the soluble fusion protein was injected without adjuvant into H-2b mice, CTL were produced that recognized an ovalbumin-derived peptide, SIINFEKL, in association with Kb. The peptide is known to arise from natural processing of ovalbumin in H-2b mouse cells, and CTL from the ovalbumin-hsp70-immunized mice and a highly effective CTL clone (4G3) raised against ovalbumin-expressing EL4 tumor cells (EG7-OVA) were equally effective in terms of the concentration of SIINFEKL required for half maximal lysis in a CTL assay. The mice were also protected against lethal challenge with ovalbumin-expressing melanoma tumor cells. Because large protein fragments or whole proteins serving as fusion partners can be cleaved into short peptides in the MHC class I processing pathway, hsp fusion proteins of the type described here are promising candidates for vaccines aimed at eliciting CD8 CTL in populations of MHC-disparate individuals. PMID- 9371815 TI - Btk dosage determines sensitivity to B cell antigen receptor cross-linking. AB - Mutations in Btk result in the B cell immunodeficiencies X-linked agammaglobulinemia (XLA) in humans and X-linked immunodeficiency (xid) in mice. Btk is a critical component of signaling pathways regulating B cell development and function. We used a genetic approach to determine whether Btk is also limiting for these processes. One allele of a murine Btk transgene expressed a dosage of Btk (25% of endogenous levels in splenic B cells) sufficient to restore normal numbers of phenotypically mature conventional B cells in xid mice. 2,4,6 trinitrophenyl-Ficoll response, anti-IgM-induced proliferation, B1 cell development, and serum IgM and IgG3 levels remained significantly impaired in these animals. B cells from Btk -/- transgenic mice also responded poorly to anti IgM, indicating that the xid mutation does not create a dominant negative form of Btk. Response to 2,4,6-trinitrophenyl-Ficoll and B cell receptor cross-linking were increased 3- to 4-fold in xid mice homozygous for the transgene. These results demonstrate that Btk is a limiting component of B cell antigen receptor signaling pathways and suggest that B cell development and response to antigen may require different levels of Btk activity. PMID- 9371816 TI - CD19 and CD22 expression reciprocally regulates tyrosine phosphorylation of Vav protein during B lymphocyte signaling. AB - B cell development and humoral immune responses are controlled by signaling thresholds established through the B lymphocyte antigen receptor (BCR) complex. BCR signaling thresholds are differentially regulated by the CD22 and CD19 cell surface receptors in vivo. B cells from CD22-deficient mice exhibit characteristics of chronic stimulation and are hyper-responsive to BCR crosslinking with augmented intracellular Ca2+ responses. By contrast, B cells from CD19-deficient mice are hypo-responsive to transmembrane signals. To identify signaling molecules involved in the positive and negative regulation of signaling thresholds, the signal transduction pathways activated after BCR crosslinking were examined in CD22- and CD19-deficient B cells. These comparisons revealed that tyrosine phosphorylation of Vav protein was uniquely augmented after BCR or CD19 crosslinking in CD22-deficient B cells, yet was modest and transient after BCR crosslinking in CD19-deficient B cells. Ligation of CD19 and CD22 in vivo is likely to positively and negatively regulate BCR signaling, respectively, because CD19 crosslinking was more efficient than BCR crosslinking at inducing Vav phosphorylation. However, simultaneous crosslinking of CD19 with the BCR resulted in a substantial decrease in Vav phosphorylation when CD22 was expressed. Thus, the differential regulation of Vav tyrosine phosphorylation by CD19 and CD22 may provide a molecular mechanism for adjusting BCR signaling thresholds. PMID- 9371817 TI - Interaction between HLA-DM and HLA-DR involves regions that undergo conformational changes at lysosomal pH. AB - Antigenic peptide loading of major histocompatibility complex class II molecules is enhanced by lysosomal pH and catalyzed by the HLA-DM molecule. The physical mechanism behind the catalytic activity of DM was investigated by using time resolved fluorescence anisotropy (TRFA) and fluorescence binding studies with the dye 8-anilino-1-naphthalenesulfonic acid (ANS). We demonstrate that the conformations of both HLA-DM and HLA-DR3, irrespective of the composition of bound peptide, are pH sensitive. Both complexes reversibly expose more nonpolar regions upon protonation. Interaction of DM with DR shields these hydrophobic domains from the aqueous environment, leading to stabilization of the DM and DR conformations. At lysosomal pH, the uncovering of additional hydrophobic patches leads to a more extensive DM-DR association. We propose that DM catalyzes class II peptide loading by stabilizing the low-pH conformation of DR, favoring peptide exchange. The DM-DR association involves a larger hydrophobic surface area with DR/class II-associated invariant chain peptides (CLIP) than with stable DR/peptide complexes, explaining the preferred association of DM with the former. The data support a release mechanism of DM from the DM-DR complex through reduction of the interactive surface, upon binding of class II molecules with antigenic peptide or upon neutralization of the DM-DR complex at the cell surface. PMID- 9371818 TI - Preferential activation of the p46 isoform of JNK/SAPK in mouse macrophages by TNF alpha. AB - A pleiotropic cytokine, tumor necrosis factor-alpha (TNF alpha), regulates the expression of multiple macrophage gene products and thus contributes a key role in host defense. In this study, we have investigated the specificity and mechanism of activation of members of the c-Jun-NH2-terminal kinase/stress activated protein kinase (JNK/SAPK) subfamily of mitogen-activated protein kinases (MAPKs) in mouse macrophages in response to stimulation with TNF alpha. Exposure of macrophages to TNF alpha stimulated a preferential increase in catalytic activity of the p46 JNK/SAPK isoform compared with the p54 JNK/SAPK isoform as determined by: (i) separation of p46 and p54 JNK/SAPKs by anion exchange liquid chromatography and (ii) selective immunodepletion of the p46 JNK/SAPK from macrophage lysates. To investigate the level of regulation of p46 JNK/SAPK activation, we determined the ability of MKK4/SEK1/JNKK, an upstream regulator of JNK/SAPKs, to phosphorylate recombinant kinase-inactive p46 and p54 JNK/SAPKs. Endogenous MKK4 was able to transphosphorylate both isoforms. In addition, both the p46 and p54 JNK/SAPK isoforms were phosphorylated on their TPY motif in response to TNF alpha stimulation as reflected by immunoblotting with a phospho-specific antibody that recognizes both kinases. Collectively, these results suggest that the level of control of p46 JNK/SAPK activation is distal not only to MKK4 but also to the p54 JNK/SAPK. Preferential isoform activation within the JNK/SAPK subfamily of MAPKs may be an important mechanism through which TNF alpha regulates macrophage phenotypic heterogeneity and differentiation. PMID- 9371819 TI - Interleukin 9: a candidate gene for asthma. AB - Asthma is a complex heritable inflammatory disorder of the airways associated with clinical signs of atopy and bronchial hyperresponsiveness. Recent studies localized a major gene for asthma to chromosome 5q31-q33 in humans. Thus, this segment of the genome represents a candidate region for genes that determine susceptibility to bronchial hyperresponsiveness and atopy in animal models. Homologs of candidate genes on human chromosome 5q31-q33 are found in four regions in the mouse genome, two on chromosome 18, and one each on chromosomes 11 and 13. We assessed bronchial responsiveness as a quantitative trait in mice and found it linked to chromosome 13. Interleukin 9 (IL-9) is located in the linked region and was analyzed as a gene candidate. The expression of IL-9 was markedly reduced in bronchial hyporesponsive mice, and the level of expression was determined by sequences within the qualitative trait locus (QTL). These data suggest a role for IL-9 in the complex pathogenesis of bronchial hyperresponsiveness as a risk factor for asthma. PMID- 9371820 TI - The R1 component of mammalian ribonucleotide reductase has malignancy-suppressing activity as demonstrated by gene transfer experiments. AB - Our recent studies have shown that deregulated expression of R2, the rate limiting component of ribonucleotide reductase, enhances transformation and malignant potential by cooperating with activated oncogenes. We now demonstrate that the R1 component of ribonucleotide reductase has tumor-suppressing activity. Stable expression of a biologically active ectopic R1 in ras-transformed mouse fibroblast 10T(1/2) cell lines, with or without R2 overexpression, led to significantly reduced colony-forming efficiency in soft agar. The decreased anchorage independence was accompanied by markedly suppressed malignant potential in vivo. In three ras-transformed cell lines, R1 overexpression resulted in abrogation or marked suppression of tumorigenicity. In addition, the ability to form lung metastases by cells overexpressing R1 was reduced by >85%. Metastasis suppressing activity also was observed in the highly malignant mouse 10T(1/2) derived RMP-6 cell line, which was transformed by a combination of oncogenic ras, myc, and mutant p53. Furthermore, in support of the above observations with the R1 overexpressing cells, NIH 3T3 cells cotransfected with an R1 antisense sequence and oncogenic ras showed significantly increased anchorage independence as compared with control ras-transfected cells. Finally, characteristics of reduced malignant potential also were demonstrated with R1 overexpressing human colon carcinoma cells. Taken together, these results indicate that the two components of ribonucleotide reductase both are unique malignancy determinants playing opposing roles in its regulation, that there is a novel control point important in mechanisms of malignancy, which involves a balance in the levels of R1 and R2 expression, and that alterations in this balance can significantly modify transformation, tumorigenicity, and metastatic potential. PMID- 9371821 TI - Impaired granulopoiesis, myelodysplasia, and early lethality in CCAAT/enhancer binding protein epsilon-deficient mice. AB - Polymorphonuclear leukocytes are essential for host defense to infectious diseases. CCAAT/enhancer binding protein epsilon (C/EBP epsilon) is preferentially expressed in granulocytes and lymphoid cells. Mice with a null mutation in C/EBP epsilon develop normally and are fertile but fail to generate functional neutrophils and eosinophils. Opportunistic infections and tissue destruction lead to death by 3-5 months of age. Furthermore, end-stage mice develop myelodysplasia, characterized by proliferation of atypical granulocytes that efface the bone marrow and result in severe tissue destruction. Thus, C/EBP epsilon is essential for terminal differentiation and functional maturation of committed granulocyte progenitor cells. PMID- 9371822 TI - Presence of an inducible HIV-1 latent reservoir during highly active antiretroviral therapy. AB - Although highly active antiretroviral therapy (HAART) in the form of triple combinations of drugs including protease inhibitors can reduce the plasma viral load of some HIV-1-infected individuals to undetectable levels, it is unclear what the effects of these regimens are on latently infected CD4+ T cells and what role these cells play in the persistence of HIV-1 infection in individuals receiving such treatment. The present study demonstrates that highly purified CD4+ T cells from 13 of 13 patients receiving HAART with an average treatment time of 10 months and with undetectable (<500 copies HIV RNA/ml) plasma viremia by a commonly used bDNA assay carried integrated proviral DNA and were capable of producing infectious virus upon cellular activation in vitro. Phenotypic analysis of HIV-1 produced by activation of latently infected CD4+ T cells revealed the presence in some patients of syncytium-inducing virus. In addition, the presence of unintegrated HIV-1 DNA in infected resting CD4+ T cells from patients receiving HAART, even those with undetectable plasma viremia, suggests persistent active virus replication in vivo. PMID- 9371823 TI - Association of the transferrin receptor in human placenta with HFE, the protein defective in hereditary hemochromatosis. AB - Hereditary hemochromatosis (HH) is a common autosomal recessive disease associated with loss of regulation of dietary iron absorption and excessive iron deposition in major organs of the body. Recently, a candidate gene for HH (also called HFE) was identified that encodes a novel MHC class I-like protein. Most patients with HH are homozygous for the same mutation in the HFE gene, resulting in a C282Y change in the HFE protein. Studies in cultured cells show that the C282Y mutation abrogates the binding of the recombinant HFE protein to beta2 microglobulin (beta2M) and disrupts its transport to the cell surface. The HFE protein was shown by immunohistochemistry to be expressed in certain epithelial cells throughout the human alimentary tract and to have a unique localization in the cryptal cells of small intestine, where signals to regulate iron absorption are received from the body. In the studies presented here, we demonstrate by immunohistochemistry that the HFE protein is expressed in human placenta in the apical plasma membrane of the syncytiotrophoblasts, where the transferrin-bound iron is normally transported to the fetus via receptor-mediated endocytosis. Western blot analyses show that the HFE protein is associated with beta2M in placental membranes. Unexpectedly, the transferrin receptor was also found to be associated with the HFE protein/beta2M complex. These studies place the normal HFE protein at the site of contact with the maternal circulation where its association with transferrin receptor raises the possibility that the HFE protein plays some role in determining maternal/fetal iron homeostasis. These findings also raise the question of whether mutations in the HFE gene can disrupt this association and thereby contribute to some forms of neonatal iron overload. PMID- 9371824 TI - Loss of ovarian function promotes angiogenesis in human ovarian carcinoma. AB - We show here that elevated levels of gonadotropins (luteinizing hormone and follicle stimulating hormone), as found in menopause or after ovariectomy, promote growth of human ovarian carcinoma by induction of tumor angiogenesis. Human epithelial ovarian cancer tumors progressed faster in ovariectomized mice. This induced growth could be attributed to the elevated levels of gonadotropins associated with loss of ovarian function because direct administration of gonadotropins also was effective in promoting tumor progression in vivo. On the other hand, gonadotropins had no direct effect on the proliferation of human ovarian cancer cells in vitro. Using MRI, we demonstrated that ovariectomy significantly (P < 0.02) induces neovascularization of human ovarian carcinoma spheroids implanted in nude mice. Moreover, conditioned medium of gonadotropin treated human ovarian carcinoma cells showed increased mitogenic activity to bovine endothelial cells, and this activity could be blocked by neutralizing antibodies against luteinizing hormone and against vascular endothelial growth factor. Accordingly, gonadotropin stimulation resulted in a dose-dependent induced expression of vascular endothelial growth factor in monolayer culture as well as in the outer proliferating cells of human ovarian cancer spheroids. These results demonstrate the significance of the elevated levels of gonadotropins, as found in menopause and in all ovarian cancer patients, on the progression of ovarian cancer and could explain the protective effect of estrogen replacement therapy. Based on these results, we suggest that hormonal therapy aimed at lowering the circulating levels of gonadotropins may possibly prolong remission in ovarian cancer by extending tumor dormancy. PMID- 9371825 TI - The maturity-onset diabetes of the young (MODY1) transcription factor HNF4alpha regulates expression of genes required for glucose transport and metabolism. AB - Hepatocyte nuclear factor 4alpha (HNF4alpha) plays a critical role in regulating the expression of many genes essential for normal functioning of liver, gut, kidney, and pancreatic islets. A nonsense mutation (Q268X) in exon 7 of the HNF4alpha gene is responsible for an autosomal dominant, early-onset form of non insulin-dependent diabetes mellitus (maturity-onset diabetes of the young; gene named MODY1). Although this mutation is predicted to delete 187 C-terminal amino acids of the HNF4alpha protein the molecular mechanism by which it causes diabetes is unknown. To address this, we first studied the functional properties of the MODY1 mutant protein. We show that it has lost its transcriptional transactivation activity, fails to dimerize and bind DNA, implying that the MODY1 phenotype is because of a loss of HNF4alpha function. The effect of loss of function on HNF4alpha target gene expression was investigated further in embryonic stem cells, which are amenable to genetic manipulation and can be induced to form visceral endoderm. Because the visceral endoderm shares many properties with the liver and pancreatic beta-cells, including expression of genes for glucose transport and metabolism, it offers an ideal system to investigate HNF4-dependent gene regulation in glucose homeostasis. By exploiting this system we have identified several genes encoding components of the glucose dependent insulin secretion pathway whose expression is dependent upon HNF4alpha. These include glucose transporter 2, and the glycolytic enzymes aldolase B and glyceraldehyde-3-phosphate dehydrogenase, and liver pyruvate kinase. In addition we have found that expression of the fatty acid binding proteins and cellular retinol binding protein also are down-regulated in the absence of HNF4alpha. These data provide direct evidence that HNF4alpha is critical for regulating glucose transport and glycolysis and in doing so is crucial for maintaining glucose homeostasis. PMID- 9371826 TI - A mammalian model for Laron syndrome produced by targeted disruption of the mouse growth hormone receptor/binding protein gene (the Laron mouse). AB - Laron syndrome [growth hormone (GH) insensitivity syndrome] is a hereditary dwarfism resulting from defects in the GH receptor (GHR) gene. GHR deficiency has not been reported in mammals other than humans. Many aspects of GHR dysfunction remain unknown because of ethical and practical limitations in studying humans. To create a mammalian model for this disease, we generated mice bearing a disrupted GHR/binding protein (GHR/BP) gene through a homologous gene targeting approach. Homozygous GHR/BP knockout mice showed severe postnatal growth retardation, proportionate dwarfism, absence of the GHR and GH binding protein, greatly decreased serum insulin-like growth factor I and elevated serum GH concentrations. These characteristics represent the phenotype typical of individuals with Laron syndrome. Animals heterozygous for the GHR/BP defect show only minimal growth impairment but have an intermediate biochemical phenotype, with decreased GHR and GH binding protein expression and slightly diminished insulin-like growth factor I levels. These findings indicate that the GHR/BP deficient mouse (Laron mouse) is a suitable model for human Laron syndrome that will prove useful for the elucidation of many aspects of GHR/BP function that cannot be obtained in humans. PMID- 9371827 TI - Altered phosphorylation and intracellular distribution of a (CUG)n triplet repeat RNA-binding protein in patients with myotonic dystrophy and in myotonin protein kinase knockout mice. AB - Myotonic dystrophy (DM) is associated with expansion of CTG repeats in the 3' untranslated region of the myotonin protein kinase (DMPK) gene. The molecular mechanism whereby expansion of the (CUG)n repeats in the 3'-untranslated region of DMPK gene induces DM is unknown. We previously isolated a protein with specific binding to CUG repeat sequences (CUG-BP/hNab50) that possibly plays a role in mRNA processing and/or transport. Here we present evidence that the phosphorylation status and intracellular distribution of the RNA CUG-binding protein, identical to hNab50 protein (CUG-BP/hNab50), are altered in homozygous DM patient and that CUG-BP/hNab50 is a substrate for DMPK both in vivo and in vitro. Data from two biological systems with reduced levels of DMPK, homozygous DM patient and DMPK knockout mice, show that DMPK regulates both phosphorylation and intracellular localization of the CUG-BP/hNab50 protein. Decreased levels of DMPK observed in DM patients and DMPK knockout mice led to the elevation of the hypophosphorylated form of CUG-BP/hNab50. Nuclear concentration of the hypophosphorylated CUG-BP/hNab50 isoform is increased in DMPK knockout mice and in homozygous DM patient. DMPK also interacts with and phosphorylates CUG BP/hNab50 protein in vitro. DMPK-mediated phosphorylation of CUG-BP/hNab50 results in dramatic reduction of the CUG-BP2, hypophosphorylated isoform, accumulation of which was observed in the nuclei of DMPK knockout mice. These data suggest a feedback mechanism whereby decreased levels of DMPK could alter phosphorylation status of CUG-BP/hNab50, thus facilitating nuclear localization of CUG-BP/hNab50. Our results suggest that DM pathophysiology could be, in part, a result of sequestration of CUG-BP/hNab50 and, in part, of lowered DMPK levels, which, in turn, affect processing and transport of specific subclass of mRNAs. PMID- 9371828 TI - An epidemic of tuberculosis with a high rate of tuberculin anergy among a population previously unexposed to tuberculosis, the Yanomami Indians of the Brazilian Amazon. AB - A survey of an emerging tuberculosis epidemic among the Yanomami Indians of the Amazonian rain forest provided a unique opportunity to study the impact of tuberculosis on a population isolated from contact with the tubercle bacillus for millennia until the mid-1960s. Within the Yanomami population, an extraordinary high prevalence of active tuberculosis (6.4% of 625 individuals clinically examined) was observed, indicating a high susceptibility to disease, even among bacille Calmette-Guerin-vaccinated individuals. Observational studies on cell mediated and humoral immune responses of the Yanomami Indians compared with contemporary residents of the region suggest profound differences in immunological responsiveness to Mycobacterium tuberculosis infection. Among the Yanomami, a very high prevalence of tuberculin skin test anergy was found. Of patients with active tuberculosis, 46% had purified protein derivative of tuberculosis reactions <10 mm; similarly 58% of recent bacillus Calmette-Guerin vaccines exhibited skin test reactions <5 mm. The Yanomami also had higher titers of antibodies against M. tuberculosis glycolipid antigens (>70%) than the control subjects comprised of Brazilians of European descent (14%). The antibodies were mostly of the IgM isotype. Among the tuberculosis patients who also produced IgG antibodies, the titers of IgG4 were significantly higher among the Yanomami than in the control population. Although it was not possible to analyze T-cell responses or patterns of lymphokine production in vitro because of the remoteness of the villages from laboratory facilities, the results suggest that the first encounter of the Yanomami Indian population with tuberculosis engenders a diminished cell-mediated immune response and an increased production antibody responses, relative to other populations with extensive previous contact with the pathogen. These findings suggest that tuberculosis may represent a powerful selective pressure on human evolution that over centuries has shaped the nature of human immune responses to infection. PMID- 9371829 TI - Overexpressed human CD44s promotes lung colonization during micrometastasis of murine fibrosarcoma cells: facilitated retention in the lung vasculature. AB - Normally nonmetastatic murine sis-transformed BALB/c 3T3 cells, transfected with human CD44s gene (hCD44s), acquire spontaneous metastatic capacity to the lung. The mechanism(s) of this facilitated micrometastasis was analyzed in an experimental metastasis model. Human CD44s overexpression promoted the earliest stages severalfold (initial implantation and subsequent stabilization of tumor cells) but was irrelevant for later stages (subsequent outgrowth) of lung experimental micrometastasis. By injecting mixed populations of parental (nonmetastatic) and CD44s-transfected cells, it was shown that cell-cell adhesion between tumor and parental cells was not promoted by hCD44s but that promotion of cell-cell adhesion to lung endothelium or specifically between transfected cells (via hyaluronan) are likely mechanisms. Results obtained with hCD44s-negative primary tumor cells and hCD44s-positive or -negative variants of lung micrometastatic cells (after s.c. injection of transfectants) confirmed the importance of CD44s overexpression for early but not late stages of experimental lung metastasis. Therefore, CD44s represents a metastasis-facilitating molecule that is irrelevant for primary tumor outgrowth but that promotes micrometastasis to the lungs at the very earliest stages. PMID- 9371830 TI - Murine hematopoietic reconstitution after tagging and selection of retrovirally transduced bone marrow cells. AB - A major problem facing the effective treatment of patients with cancer is how to get the specific antitumor agent into every tumor cell. In this report we describe the use of a strategy that, by using retroviral vectors encoding a truncated human CD5 cDNA, allows the selection of only the infected cells, and we show the ability to obtain, before bone marrow transplantation, a population of 5 fluouracil-treated murine bone marrow cells that are 100% marked. This marked population of bone marrow cells is able to reconstitute the hematopoietic system in lethally irradiated mice, indicating that the surface marker lacks deleterious effects on the functionality of bone marrow cells. No gross abnormalities in hematopoiesis were detected in mice repopulated with CD5-expressing cells. Nevertheless, a significant proportion of the hematopoietic cells no longer expresses the surface marker CD5 in the 9-month-old recipient mice. This transcriptional inactivity of the proviral long terminal repeat (LTR) was accompanied by de novo methylation of the proviral sequences. Our results show that the use of the CD5 as a retrovirally encoded marker enables the rapid, efficient, and nontoxic selection in vitro of infected primary cells, which can entirely reconstitute the hematopoietic system in mice. These results should now greatly enhance the power of studies aimed at addressing questions such as generation of cancer-negative hematopoiesis. PMID- 9371831 TI - Use of model plant hosts to identify Pseudomonas aeruginosa virulence factors. AB - We used plants as an in vivo pathogenesis model for the identification of virulence factors of the human opportunistic pathogen Pseudomonas aeruginosa. Nine of nine TnphoA mutant derivatives of P. aeruginosa strain UCBPP-PA14 that were identified in a plant leaf assay for less pathogenic mutants also exhibited significantly reduced pathogenicity in a burned mouse pathogenicity model, suggesting that P. aeruginosa utilizes common strategies to infect both hosts. Seven of these nine mutants contain TnphoA insertions in previously unknown genes. These results demonstrate that an alternative nonvertebrate host of a human bacterial pathogen can be used in an in vivo high throughput screen to identify novel bacterial virulence factors involved in mammalian pathogenesis. PMID- 9371833 TI - CooB plays a chaperone-like role for the proteins involved in formation of CS1 pili of enterotoxigenic Escherichia coli. AB - CS1 pili serve as the prototype of a class of filamentous appendages found on the surface of strains of enterotoxigenic Escherichia coli. The four genes needed to synthesize functional CS1 pili in E. coli K12 are: cooA, which encodes the major pilin protein; cooD, which encodes a minor pilin protein found at the tip of the structure; cooC, which encodes a protein found in the outer membrane of piliated bacteria; and cooB. We show here that CooB, which is required for pilus assembly but is not part of the final structure, stabilizes CooA, CooC, and CooD. We previously reported that CooB is complexed with CooA in the periplasm and show here that CooB also is found complexed with CooD in the periplasm. CooB is associated with the membrane fraction only in the presence of CooC, suggesting that these two proteins also interact. This suggests that although it has no homology to known chaperone proteins, CooB serves a chaperone-like role for assembly of CS1. PMID- 9371832 TI - Inactivation of the alpha C protein antigen gene, bca, by a novel shuttle/suicide vector results in attenuation of virulence and immunity in group B Streptococcus. AB - The alpha C protein of group B Streptococcus (GBS) is a major surface-associated antigen. Although its role in the biology and virulence of GBS has not been defined, it is opsonic and capable of eliciting protective immunity. The alpha C protein is widely distributed among clinical isolates and is a potential protein carrier and antigen in conjugate vaccines to prevent GBS infections. The structural gene for the alpha C protein, bca, has been cloned and sequenced. The protein encoded by bca is related to a class of surface-associated proteins of gram-positive cocci involved in virulence and immunity. To investigate the potential roles of the alpha C protein, bca null mutants were generated in which the bca gene was replaced with a kanamycin resistance cassette via homologous recombination using a novel shuttle/suicide vector. Studies of lethality in neonatal mice showed that the virulence of the bca null mutants was attenuated 5- to 7-fold when compared with the isogenic wild-type strain A909. Significant differences in mortality occurred in the first 24 h, suggesting that the role of the alpha antigen is important in the initial stages of the infection. In contrast to A909, bca mutants were no longer killed by polymorphonuclear leukocytes in the presence of alpha-specific antibodies in an in vitro opsonophagocytic assay. In contrast to previous studies, alpha antigen expression does not appear to play a role in resistance to opsonophagocytosis in the absence of alpha-specific antibodies. In addition, antibodies to the alpha C protein did not passively protect neonatal mice from lethal challenge with bca mutants, suggesting that these epitopes are uniquely present within the alpha antigen as expressed from the bca gene. Therefore, the alpha C protein is important in the pathogenesis of GBS infection and is a target for protective immunity in the development of GBS vaccines. PMID- 9371834 TI - Electrophysiological studies on rat dorsal root ganglion neurons after peripheral axotomy: changes in responses to neuropeptides. AB - The effect of three peptides, galanin, sulfated cholecystokinin octapeptide, and neurotensin (NT), was studied on acutely extirpated rat dorsal root ganglia (DRGs) in vitro with intracellular recording techniques. Both normal and peripherally axotomized DRGs were analyzed, and recordings were made from C-type (small) and A-type (large) neurons. Galanin and sulfated cholecystokinin octapeptide, with one exception, had no effect on normal C- and A-type neurons but caused an inward current in both types of neurons after sciatic nerve cut. In normal rats, NT caused an outward current in C-type neurons and an inward current in A-type neurons. After sciatic nerve cut, NT only caused an inward current in both C- and A-type neurons. These results suggest that (i) normal DRG neurons express receptors on their soma for some but not all peptides studied, (ii) C- and A-type neurons can have different types of receptors, and (iii) peripheral nerve injury can change the receptor phenotype of both C- and A-type neurons and may have differential effects on these neuron types. PMID- 9371835 TI - Marked decrease of neuropeptide Y Y2 receptor binding sites in the hippocampus in murine prion disease. AB - Using autoradiographic binding methodology with monoiodinated peptide YY together with the agonists neuropeptide Y (NPY) and NPY (13-36), as well as in situ hybridization with oligonucleotide probes complementary to the NPY Y2 receptor (Y2-R) mRNA, we have studied whether or not intracerebral prion inoculation affects Y2-Rs in male CD-1 mice. Monoiodinated peptide YY binding, mainly representing Y2-Rs, was down-regulated by 85% in the CA1 strata oriens and radiatum and by 50-65% in the CA3 stratum oriens 110-140 days postinoculation. In the CA3 stratum radiatum, where the mossy fibers from the dentate granule cells project, there was a significant decrease in PYY binding at 110-120 days. Y2-R mRNA, moderately expressed both in the CA1 and CA3 pyramidal cell layers and the granule cell layer in the dentate gyrus, showed a slight, but not significant, decrease in CA3 neurons 130 days postinoculation. The results indicate that the accumulation of the scrapie prion protein in the CA1-3 region strongly inhibits NPY binding at the Y2-Rs, which, however, is only marginally due to reduced Y2-R mRNA expression. The loss of the ability of NPY to bind to inhibitory Y2-Rs may cause dysfunction of hippocampal circuits and may contribute to the clinical symptoms in mouse scrapie. PMID- 9371836 TI - The synthesis of ATP by glycolytic enzymes in the postsynaptic density and the effect of endogenously generated nitric oxide. AB - The major contribution of this paper is the finding of a glycolytic source of ATP in the isolated postsynaptic density (PSD). The enzymes involved in the generation of ATP are glyceraldehyde-3-phosphate dehydrogenase (G3PD) and phosphoglycerate kinase (PGK). Lactate dehydrogenase (LDH) is available for the regeneration of NAD+, as well as aldolase for the regeneration of glyceraldehyde 3-phosphate (G3P). The ATP was shown to be used by the PSD Ca2+/calmodulin dependent protein kinase and can probably be used by two other PSD kinases, protein kinase A and protein kinase C. We confirmed by immunocytochemistry the presence of G3PD in the PSD and its binding to actin. Also present in the PSD is NO synthase, the source of NO. NO increases the binding of NAD, a G3PD cofactor, to G3PD and inhibits its activity as also found by others. The increased NAD binding resulted in an increase in G3PD binding to actin. We confirmed the autophosphorylation of G3PD by ATP, and further found that this procedure also increased the binding of G3PD to actin. ATP and NO are connected in that the formation of NO from NOS at the PSD resulted, in the presence of NAD, in a decrease of ATP formation in the PSD. In the discussion, we raise the possible roles of G3PD and of ATP in protein synthesis at the PSD, the regulation by NO, as well as the overall regulatory role of the PSD complex in synaptic transmission. PMID- 9371837 TI - Neurotrophin release by neurotrophins: implications for activity-dependent neuronal plasticity. AB - Neurotrophins, secreted in an activity-dependent manner, are thought to be involved in the activity-dependent refinement of synaptic connections. Here we demonstrate that in hippocampal neurons and the rat pheochromocytoma cell line PC12 application of exogenous neurotrophins induces secretion of neurotrophins, an effect that is mediated by the activation of tyrosine kinase neurotrophin receptors (Trks). Like activity-dependent secretion of neurotrophins, neurotrophin-induced neurotrophin secretion requires mobilization of calcium from intracellular stores. Because neurotrophins are likely to be released from both dendrites and axons, neurotrophin-induced neurotrophin release represents a potential positive feedback mechanism, contributing to the reinforcement and stabilization of synaptic connections. PMID- 9371838 TI - Two amyloid precursor protein transgenic mouse models with Alzheimer disease-like pathology. AB - Mutations in the amyloid precursor protein (APP) gene cause early-onset familial Alzheimer disease (AD) by affecting the formation of the amyloid beta (A beta) peptide, the major constituent of AD plaques. We expressed human APP751 containing these mutations in the brains of transgenic mice. Two transgenic mouse lines develop pathological features reminiscent of AD. The degree of pathology depends on expression levels and specific mutations. A 2-fold overexpression of human APP with the Swedish double mutation at positions 670/671 combined with the V717I mutation causes A beta deposition in neocortex and hippocampus of 18-month old transgenic mice. The deposits are mostly of the diffuse type; however, some congophilic plaques can be detected. In mice with 7-fold overexpression of human APP harboring the Swedish mutation alone, typical plaques appear at 6 months, which increase with age and are Congo Red-positive at first detection. These congophilic plaques are accompanied by neuritic changes and dystrophic cholinergic fibers. Furthermore, inflammatory processes indicated by a massive glial reaction are apparent. Most notably, plaques are immunoreactive for hyperphosphorylated tau, reminiscent of early tau pathology. The immunoreactivity is exclusively found in congophilic senile plaques of both lines. In the higher expressing line, elevated tau phosphorylation can be demonstrated biochemically in 6-month-old animals and increases with age. These mice resemble major features of AD pathology and suggest a central role of A beta in the pathogenesis of the disease. PMID- 9371839 TI - A hierarchical neuronal network for planning behavior. AB - Planning a goal-directed sequence of behavior is a higher function of the human brain that relies on the integrity of prefrontal cortical areas. In the Tower of London test, a puzzle in which beads sliding on pegs must be moved to match a designated goal configuration, patients with lesioned prefrontal cortex show deficits in planning a goal-directed sequence of moves. We propose a neuronal network model of sequence planning that passes this test and, when lesioned, fails in a way that mimics prefrontal patients' behavior. Our model comprises a descending planning system with hierarchically organized plan, operation, and gesture levels, and an ascending evaluative system that analyzes the problem and computes internal reward signals that index the correct/erroneous status of the plan. Multiple parallel pathways connecting the evaluative and planning systems amend the plan and adapt it to the current problem. The model illustrates how specialized hierarchically organized neuronal assemblies may collectively emulate central executive or supervisory functions of the human brain. PMID- 9371840 TI - Role of intrinsic synaptic circuitry in collicular sensorimotor integration. AB - The superficial gray layer of the superior colliculus contains a map that represents the visual field, whereas the underlying intermediate gray layer contains a vector map of the saccades that shift the direction of gaze. These two maps are aligned so that a particular region of the visual field is represented directly above the neurons that orient the highest acuity area of the retina toward that region. Although it has been proposed that the transmission of information from the visuosensory to the motor map plays an important role in the generation of visually guided saccades, experiments have failed to demonstrate any functional linkage between the two layers. We examined synaptic transmission between these layers in vitro by stimulating the superficial layer while using whole-cell patch-clamp methods to measure the responses of intermediate layer neurons. Stimulation of superficial layer neurons evoked excitatory postsynaptic currents in premotor cells. This synaptic input was columnar in organization, indicating that the connections between the layers link corresponding regions of the visuosensory and motor maps. Excitatory postsynaptic currents were large enough to evoke action potentials and often occurred in clusters similar in duration to the bursts of action potentials that premotor cells use to command saccades. Our results indicate the presence of functional connections between the superficial and intermediate layers and show that such connections could play a significant role in the generation of visually guided saccades. PMID- 9371841 TI - A homeodomain gene Ptx3 has highly restricted brain expression in mesencephalic dopaminergic neurons. AB - The mesencephalic dopaminergic (mesDA) system regulates behavior and movement control and has been implicated in psychiatric and affective disorders. We have identified a bicoid-related homeobox gene, Ptx3, a member of the Ptx-subfamily, that is uniquely expressed in these neurons. Its expression starting at E11.5 in the developing mouse midbrain correlates with the appearance of mesDA neurons. The number of Ptx3-expressing neurons is reduced in Parkinson patients, and these neurons are absent from 6-hydroxydopamine-lesioned rats, an animal model for this disease. Thus, Ptx3 is a unique transcription factor marking the mesDA neurons at the exclusion of other dopaminergic neurons, and it may be involved in developmental determination of this neuronal lineage. PMID- 9371842 TI - Disruption of the m1 receptor gene ablates muscarinic receptor-dependent M current regulation and seizure activity in mice. AB - Muscarinic acetylcholine receptors are members of the G protein-coupled receptor superfamily expressed in neurons, cardiomyocytes, smooth muscle, and a variety of epithelia. Five subtypes of muscarinic acetylcholine receptors have been discovered by molecular cloning, but their pharmacological similarities and frequent colocalization make it difficult to assign functional roles for individual subtypes in specific neuronal responses. We have used gene targeting by homologous recombination in embryonic stem cells to produce mice lacking the m1 receptor. These mice show no obvious behavioral or histological defects, and the m2, m3, and m4 receptors continue to be expressed in brain with no evidence of compensatory induction. However, the robust suppression of the M-current potassium channel activity evoked by muscarinic agonists in sympathetic ganglion neurons is completely lost in m1 mutant mice. In addition, both homozygous and heterozygous mutant mice are highly resistant to the seizures produced by systemic administration of the muscarinic agonist pilocarpine. Thus, the m1 receptor subtype mediates M current modulation in sympathetic neurons and induction of seizure activity in the pilocarpine model of epilepsy. PMID- 9371843 TI - Gi regulation of secretory vesicle swelling examined by atomic force microscopy. AB - In the last decade, several monomeric and heterotrimeric guanine nucleotide binding proteins have been identified to associate with secretory vesicles and to be implicated in exocytosis. Vesicle volume also has been proposed to play a regulatory role in secretory vesicle fusion at the plasma membrane. However, the molecular mechanism of function of the guanine nucleotide binding proteins and of the regulation of secretory vesicle volume in the exocytotic process remains unclear. In this study, we report association of the secretory vesicle membrane with the alpha subunit of a heterotrimeric GTP binding protein G(alpha i3) and implicate its involvement in vesicle swelling. Using an atomic force microscope in combination with confocal microscopy, we were able to study the dynamics of isolated zymogen granules, the secretory vesicles in exocrine pancreas. Exposure of zymogen granules to GTP resulted in a 15-25% increase in vesicle height as measured by the atomic force microscope and a similar increase in vesicle diameter as determined by confocal microscopy. Mas7, an active mastoparan analog known to stimulate Gi proteins, was found to stimulate the GTPase activity of isolated zymogen granules and cause swelling. Increase in vesicle size in the presence of GTP, NaF, and Mas7 were irreversible and KCl-sensitive. Ca2+ had no effect on zymogen granule size. Taken together, the results indicate that G(alpha i3) protein localized in the secretory vesicle membrane mediates vesicle swelling, a potentially important prerequisite for vesicle fusion at the cell plasma membrane. PMID- 9371844 TI - Molecular mechanism of use-dependent calcium channel block by phenylalkylamines: role of inactivation. AB - The role of channel inactivation in the molecular mechanism of calcium (Ca2+) channel block by phenylalkylamines (PAA) was analyzed by designing mutant Ca2+ channels that carry the high affinity determinants of the PAA receptor site [Hockerman, G. H., Johnson, B. D., Scheuer, T., and Catterall, W. A. (1995) J. Biol. Chem. 270, 22119-22122] but inactivate at different rates. Use-dependent block by PAAs was studied after expressing the mutant Ca2+ channels in Xenopus oocytes. Substitution of single putative pore-orientated amino acids in segment IIIS6 by alanine (F-1499-A, F-1500-A, F-1510-A, I-1514-A, and F-1515-A) gradually slowed channel inactivation and simultaneously reduced inhibition of barium currents (I(Ba)) by (-)D600 upon depolarization by 100 ms steps at 0.1 Hz. This apparent reduction in drug sensitivity was only evident if test pulses were applied at a low frequency of 0.1 Hz and almost disappeared at the frequency of 1 Hz. (-)D600 slowed I(Ba) recovery after maintained membrane depolarization (1-3 sec) to a comparable extent in all channel constructs. A drug-induced delay in the onset of I(Ba) recovery from inactivation suggests that PAAs promote the transition to a deep inactivated channel conformation. These findings indicate that apparent PAA sensitivity of Ca2+ channels is not only defined by drug interaction with its receptor site but also crucially dependent on intrinsic gating properties of the channel molecule. A molecular model for PAA-Ca2+ channel interaction that accounts for the relationship between drug induced inactivation and channel block by PAA is proposed. PMID- 9371845 TI - Basolateral membrane targeting of a renal-epithelial inwardly rectifying potassium channel from the cortical collecting duct, CCD-IRK3, in MDCK cells. AB - We recently cloned an inward-rectifying K channel (Kir) cDNA, CCD-IRK3 (mKir 2.3), from a cortical collecting duct (CCD) cell line. Although this recombinant channel shares many functional properties with the "small-conductance" basolateral membrane Kir channel in the CCD, its precise subcellular localization has been difficult to elucidate by conventional immunocytochemistry. To circumvent this problem, we studied the targeting of several different epitope tagged CCD-IRK3 in a polarized renal epithelial cell line. Either the 11-amino acid span of the vesicular stomatitis virus (VSV) G glycoprotein (P5D4 epitope) or a 6-amino acid epitope of the bovine papilloma virus capsid protein (AU1) was genetically engineered on the extreme N terminus of CCD-IRK3. As determined by patch-clamp and two-microelectrode voltage-clamp analyses in Xenopus oocytes, neither tag affected channel function; no differences in cation selectivity, barium block, single channel conductance, or open probability could be distinguished between the wild-type and the tagged constructs. MDCK cells were transfected with tagged CCD-IRK3, and several stable clonal cell lines were generated by neomycin-resistance selection. Immunoprecipitation studies with anti P5D4 or anti-AU1 antibodies readily detected the predicted-size 50-kDa protein in the transfected cells lines but not in wild-type or vector-only (PcB6) transfected MDCK cells. As visualized by indirect immunofluorescence and confocal microscopy, both the tagged CCD-IRK3 forms were exclusively detected on the basolateral membrane. To assure that the VSV G tag was not responsible for the targeting, the P5D4 epitope modified by a site-directed mutagenesis (Y2F) to remove a potential basolateral targeting signal contained in this tag. VSV(Y2F) was also detected exclusively on the basolateral membrane, confirming bona fide IRK3 basolateral expression. These observations, with our functional studies, suggest that CCD-IRK3 may encode the small-conductance CCD basolateral K channel. PMID- 9371846 TI - Killing K channels with TEA+. AB - Tetraethylammonium (TEA+) is widely used for reversible blockade of K channels in many preparations. We noticed that intracellular perfusion of voltage-clamped squid giant axons with a solution containing K+ and TEA+ irreversibly decreased the potassium current when there was no K+ outside. Five minutes of perfusion with 20 mM TEA+, followed by removal of TEA+, reduced potassium current to < 5% of its initial value. The irreversible disappearance of K channels with TEA+ could be prevented by addition of > or = 10 mM K+ to the extracellular solution. The rate of disappearance of K channels followed first-order kinetics and was slowed by reducing the concentration of TEA+. Killing is much less evident when an axon is held at -110 mV to tightly close all of the channels. The longer-chain TEA+ derivative decyltriethylammonium (C10+) had irreversible effects similar to TEA+. External K+ also protected K channels against the irreversible action of C10+. It has been reported that removal of all K+ internally and externally (dekalification) can result in the disappearance of K channels, suggesting that binding of K+ within the pore is required to maintain function. Our evidence further suggests that the crucial location for K+ binding is external to the (internal) TEA+ site and that TEA+ prevents refilling of this location by intracellular K+. Thus in the absence of extracellular K+, application of TEA+ (or C10+) has effects resembling dekalification and kills the K channels. PMID- 9371847 TI - Australian lungfish neurohypophysial hormone genes encode vasotocin and [Phe2]mesotocin precursors homologous to tetrapod-type precursors. AB - In view of the well-established role of neurohypophysial hormones in osmoregulation of terrestrial vertebrates, lungfishes are a key group for study of the molecular and functional evolution of the hypothalamo-neurohypophysial system. Here we report on the primary structure of the precursors encoding vasotocin (VT) and [Phe2]mesotocin ([Phe2]MT) of the Australian lungfish, Neoceratodus forsteri. Genomic sequence analysis and Northern blot analysis confirmed that [Phe2]MT is a native oxytocin family peptide in the Australian lungfish, although it has been reported that the lungfish neurohypophysis contains MT. The VT precursor consists of a signal peptide, VT, that is connected to a neurophysin by a Gly-Lys-Arg sequence, and a copeptin moiety that includes a Leu-rich core segment and a glycosylation site. In contrast, the [Phe2]MT precursor does not contain a copeptin moiety. These structural features of the lungfish precursors are consistent with those in tetrapods, but different from those in teleosts where both VT and isotocin precursors contain a copeptin-like moiety without a glycosylation site at the carboxyl terminals of their neurophysins. Comparison of the exon/intron organization also supports homology of the lungfish [Phe2]MT gene with tetrapod oxytocin/MT genes, rather than with teleost isotocin genes. Moreover, molecular phylogenetic analysis shows that neurohypophysial hormone genes of the lungfish are closely related to those of the toad. The present results along with previous morphological findings indicate that the hypothalamo-neurohypophysial system of the lungfish has evolved along the tetrapod lineage, whereas the teleosts form a separate lineage, both within the class Osteichthyes. PMID- 9371848 TI - A deletion in an indole synthase gene is responsible for the DIMBOA-deficient phenotype of bxbx maize. AB - The biosynthesis of DIMBOA, a pesticidal secondary metabolite of maize, branches off the tryptophan pathway. We have previously demonstrated that indole is the last intermediate common to both the tryptophan and hydroxamic acid pathways. The earliest discovered mutant in the DIMBOA pathway, bxbx (benzoxazineless), is deficient in the production of DIMBOA and related compounds. This paper presents evidence that a gene identified by Kramer and Koziel [Kramer, V. C. & Koziel, M. G. (1995) Plant Mol. Biol. 27, 1183-1188] as maize tryptophan synthase alpha (TSA) is the site of the genetic lesion in the DIMBOA-deficient mutant maize line bxbx. We demonstrate that the TSA gene has sustained a 924-bp deletion in bxbx compared with its counterpart in wild-type maize. We report that the TSA gene maps to the same location as the bxbx mutation, on the short arm of chromosome 4. We present evidence that the very early and very high level of expression of TSA corresponds to the timing and level of DIMBOA biosynthesis but is strikingly different from the expression of the maize tryptophan synthase beta (TSB) genes. We show that feeding indole to bxbx seedlings restores their ability to synthesize DIMBOA. We conclude that the maize enzyme initially named tryptophan synthase alpha in fact is a DIMBOA biosynthetic enzyme, and we propose that it be renamed indole synthase. This work confirms and enlarges upon the findings of Frey et al. [Frey, M., Chomet, P., Glawischniq, E., Stettner, C., Grun, S., Winklmair, A., Eisenreich, W., Bacher, A., Meeley, R. B., Briggs, S. P., Simcox, K. & Gierl, A. (1997) Science 277, 696-699], which appeared while the present paper was in review. PMID- 9371849 TI - ATPases and phosphate exchange activities in magnesium chelatase subunits of Rhodobacter sphaeroides. AB - Three separate proteins, BchD, BchH, and BchI, together with ATP, insert magnesium into protoporphyrin IX. An analysis of ATP utilization by the subunits revealed the following: BchH catalyzed ATP hydrolysis at the rate of 0.9 nmol per min per mg of protein. BchI and BchD, tested individually, had no ATPase activity but, when combined, hydrolyzed ATP at the rate of 117.9 nmol/min per mg of protein. Magnesium ions were required for the ATPase activities of both BchH and BchI+D, and these activities were inhibited 50% by 2 mM o-phenanthroline. BchI additionally catalyzed a phosphate exchange reaction from ATP and ADP. We conclude that ATP hydrolysis by BchI+D is required for an activation step in the magnesium chelatase reaction, whereas ATPase activity of BchH and the phosphate exchange activity of BchI participate in subsequent reactions leading to the insertion of Mg2+ into protoporphyrin IX. PMID- 9371850 TI - Phytosulfokine-alpha, a sulfated pentapeptide, stimulates the proliferation of rice cells by means of specific high- and low-affinity binding sites. AB - Peptide growth factors were isolated from conditioned medium derived from rice (Oryza sativa L.) suspension cultures and identified to be a sulfated pentapeptide [H-Tyr(SO3H)-Ile-Tyr(SO3H)-Thr-Gln-OH] and its C-terminal-truncated tetrapeptide [H-Tyr(SO3H)-Ile-Tyr(SO3H)-Thr-OH]. These structures were identical to the phytosulfokines originally found in asparagus (Asparagus officinalis L.) mesophyll cultures. The pentapeptide [phytosulfokine-alpha (PSK-alpha)] very strongly stimulated colony formation of rice protoplasts at concentrations above 10(-8) M, indicating a similar mode of action in rice of phytosulfokines. Binding assays using 35S-labeled PSK-alpha demonstrated the existence of both high- and low-affinity specific saturable binding sites on the surface of rice cells in suspension. Analysis of [35S]PSK-alpha binding in differential centrifugation fractions suggested association of the binding with a plasma membrane-enriched fraction. The apparent Kd values for [35S]PSK-alpha binding were found to be 1 x 10(-9) M for the high-affinity type and 1 x 10(-7) M for the low-affinity type, with maximal numbers of binding sites of 1 x 10(4) sites per cell and 1 x 10(5) sites per cell, respectively. Competition studies with [35S]PSK-alpha and several synthetic PSK-alpha analogs demonstrated that only peptides that possesses mitogenic activity can effectively displace the radioligand. These results suggest that a signal transduction pathway mediated by peptide factors is involved in plant cell proliferation. PMID- 9371851 TI - Brain activity in visual cortex predicts individual differences in reading performance. AB - The relationship between brain activity and reading performance was examined to test the hypothesis that dyslexia involves a deficit in a specific visual pathway known as the magnocellular (M) pathway. Functional magnetic resonance imaging was used to measure brain activity in dyslexic and control subjects in conditions designed to preferentially stimulate the M pathway. Dyslexics showed reduced activity compared with controls both in the primary visual cortex and in a secondary cortical visual area (MT+) that is believed to receive a strong M pathway input. Most importantly, significant correlations were found between individual differences in reading rate and brain activity. These results support the hypothesis for an M pathway abnormality in dyslexia and imply a strong relationship between the integrity of the M pathway and reading ability. PMID- 9371852 TI - Appendicular robusticity and the paleobiology of modern human emergence. AB - The emergence of modern humans in the Late Pleistocene, whatever its phylogenetic history, was characterized by a series of behaviorally important shifts reflected in aspects of human hard tissue biology and the archeological record. To elucidate these shifts further, diaphyseal cross-sectional morphology was analyzed by using cross-sectional areas and second moments of area of the mid distal humerus and midshaft femur. The humeral diaphysis indicates a gradual reduction in habitual load levels from Eurasian late archaic, to Early Upper Paleolithic early modern, to Middle Upper Paleolithic early modern hominids, with the Levantine Middle Paleolithic early modern humans being a gracile anomalous outlier. The femoral diaphysis, once variation in ecogeographically patterned body proportions is taken into account, indicates no changes across the pre 30,000 years B.P. samples in habitual locomotor load levels, followed by a modest decrease through the Middle Upper Paleolithic. PMID- 9371853 TI - Prophylactic use of implanted cardiac defibrillators in patients at high risk for ventricular arrhythmias after coronary-artery bypass graft surgery. Coronary Artery Bypass Graft (CABG) Patch Trial Investigators. AB - BACKGROUND: Patients with coronary heart disease, left ventricular dysfunction, and abnormalities on signal-averaged electrocardiograms have an increased risk sudden death. We evaluated the effect on survival of the prophylactic implantation of cardioverter-defibrillators in such patients at the time of coronary-artery bypass surgery. METHODS: Over the course of five years, 37 clinical centers screened all patients who were scheduled for elective coronary bypass surgery. Patients were eligible for the trial if they were less than 80 years old, had a left ventricular ejection fraction of less than 0.36, and had abnormalities on signal-averaged electrocardiograms. We identified 1422 eligible patients, enrolled 1055, and randomly assigned 900 to therapy with an implantable cardioverter-defibrillator (446 patients) or to the control group (454 patients). The primary end point of the study was overall mortality, and the two groups were compared in an intention-to-treat analysis. RESULTS: The base-line characteristics of the two groups were similar. During an average follow-up of 32+/-16 months, there were 101 deaths in the defibrillator group (71 from cardiac causes) and 95 in the control group (72 from cardiac causes). The hazard ratio for death from any cause was 1.07 (95 percent confidence interval, 0.81 to 1.42; P=0.64). There was no statistically significant interaction between defibrillator therapy and any of 10 preselected base-line covariates. CONCLUSIONS: We found no evidence of improved survival among patients with coronary heart disease, a depressed left ventricular ejection fraction, and an abnormal signal-averaged electrocardiogram in whom a defibrillator was implanted prophylactically at the time of elective coronary bypass surgery. PMID- 9371854 TI - Circulating activated endothelial cells in sickle cell anemia. AB - BACKGROUND: The vascular wall participates in the pathogenesis of sickle cell disease. To determine whether the endothelium is activated in this disease, we studied the number, origin, and surface phenotype of circulating endothelial cells in patients with sickle cell anemia. METHODS: We used immunohistochemical examination of buffy-coat smears to enumerate circulating endothelial cells, and we evaluated the surface phenotype by applying preparations of circulating endothelial cells. An immunofluorescence microscopy panel of antibodies was used, including a specific anti-endothelial-cell antibody, P1H12. RESULTS: Mean (+/-SD) numbers of circulating endothelial cells in normal blood donors, patients with sickle cell trait, and patients with hemolytic anemias not due to hemoglobin S were 2.6+/-1.6, 3.0+/-2.6, and 2.0+/-0.8 per milliliter of whole blood, respectively. Patients with sickle cell anemia who presented with acute painful episodes had 22.8+/-18.2 circulating endothelial cells per milliliter of blood (P<0.001 for the comparison with normal donors), and patients with no such events within one month before or after blood sampling had 13.2+/-11.8 circulating endothelial cells per milliliter of blood (P=0.002 for the comparison with normal donors and P=0.019 for the comparison with patients with acute events). Serial observations of three patients showed a tendency toward higher levels of circulating endothelial cells at the onset of acute painful crises. The average viability of circulating endothelial cells was 66+/-30 percent. In patients with sickle cell anemia, regardless of clinical status, the circulating endothelial cells were predominantly microvascular in origin (CD36-positive), and most of the cells expressed four markers of endothelial-cell activation: intercellular adhesion molecule 1, vascular-cell adhesion molecule 1, E-selectin, and P selectin. CONCLUSIONS: Our studies suggest that the vascular endothelium is activated in patients with sickle cell anemia, regardless of the patients' clinical status. Adhesion proteins on activated endothelial cells may have a role in the vascular pathology of sickle cell disease. PMID- 9371855 TI - Selective screening for gestational diabetes mellitus. Toronto Trihospital Gestational Diabetes Project Investigators. AB - BACKGROUND: The usual approach to detecting gestational diabetes mellitus is to screen all pregnant women by measuring their plasma glucose after a 50-g oral glucose load at 24 to 28 weeks' gestation. Women are referred for an oral glucose tolerance test if the plasma glucose concentration one hour later is > or = 140 mg per deciliter (7.8 mmol per liter). We hypothesized that the efficiency of screening could be enhanced by considering women's risks of gestational diabetes on the basis of their clinical characteristics. METHODS: We studied 3131 pregnant women who underwent both the screening and the diagnostic tests. We randomly selected data on half the women and used them to derive new screening strategies. We categorized each woman's risk of gestational diabetes mellitus on the basis of her age, body-mass index before pregnancy, and race. We developed strategies that entailed no screening for low-risk women, usual care for intermediate-risk women, and universal screening with lower thresholds -- plasma glucose values of 130 mg per deciliter (7.2 mmol per liter) or 128 mg per deciliter (7.1 mmol per liter) - for high-risk women. The strategies were validated with data on the other half of the women. RESULTS: The new strategies allowed a 34.6 percent reduction in the number of screening tests performed (95 percent confidence interval, 32.3 to 37.0) and detected 81.2 to 82.6 percent of the women with gestational diabetes as compared with the 78.3 percent detected through usual care. The percentage of false positive screening tests was significantly reduced, from 17.9 percent with usual care to 16.0 per cent (P=0.02) or 15.4 percent (P<0.001) with the new strategies, depending on the threshold values for high-risk women. CONCLUSIONS: Consideration of women's clinical characteristics allows efficient selective screening for gestational diabetes. PMID- 9371856 TI - A family with hypogonadotropic hypogonadism and mutations in the gonadotropin releasing hormone receptor. PMID- 9371857 TI - Images in clinical medicine. Peliosis hepatis. PMID- 9371858 TI - Management of multiple sclerosis. PMID- 9371860 TI - Clinical trials of implantable defibrillators. PMID- 9371861 TI - Sickle cell disease and the endothelium. PMID- 9371863 TI - First, do no harm (pending prior approval) PMID- 9371862 TI - Screening for gestational diabetes mellitus. PMID- 9371864 TI - Assessing hibernating myocardium: an emerging cost-effectiveness issue. PMID- 9371865 TI - Fluorine-18 fluorodeoxyglucose positron emission tomography and iodine-131 whole body scintigraphy in the follow-up of differentiated thyroid cancer. AB - Metastases of differentiated thyroid cancer may show different uptake patterns for fluorine-18 fluorodeoxyglucose and [131I]NaI. FDG positron emission tomography (PET), iodine-131 whole-body scintigraphy (131I WBS) and magnetic resonance imaging were performed in 58 unselected patients, and spiral computed tomography (CT) of the lung in 25 patients. Thirty-eight patients presented with papillary carcinomas, 15 patients with follicular carcinomas and five patients with variants of follicular carcinoma. Primary tumour stage (pT) was pT1 in 3, pT2 in 19, pT3 in 11 and pT4 in 25 cases. For the detection of metastases, FDG PET was found to have a sensitivity of 50%, 131I WBS a sensitivity of 61%, and the two methods combined a sensitivity of 86%. When FDG PET was limited to patients with elevated thyroglobulin (Tg) levels and negative 131I WBS, the sensitivity of this algorithm was 82%. Of the 21 patients with lymph node metastases, seven presented with FDG uptake but no iodine uptake. In four of them, a second FDG hot spot appeared in a lymph node metastasis of normal size. Five of the seven patients underwent surgery. None of the eight patients with pulmonary metastases smaller than 1 cm exhibited FDG uptake, while five of them had iodine uptake. All had positive results on spiral CT. In conclusion, FDG PET cannot be substituted for 131I WBS. If the Tg level is elevated and 131I WBS is negative, FDG PET can be used to detect lymph node metastases and complements anatomical imaging. A spiral CT of the lung is useful to exclude pulmonary metastases before planning a dissection of iodine-negative lymph node metastases. PMID- 9371866 TI - Can bone metabolism markers be adopted as an alternative to scintigraphic imaging in monitoring bone metastases from breast cancer? AB - Bone scintigraphy plays a major role in the diagnosis of bone metastases. The clinical utility of new biochemical markers of bone metabolism has recently been investigated in various bone diseases. This study evaluated the role of some bone metabolism markers in comparison with bone scan in the follow-up of breast cancer patients. We studied 149 patients with breast cancer, 33 (22%) of whom had bone metastases. IRMAs were used for the evaluation of blood levels of osteocalcin, bone alkaline phosphatase (BAP), the C-terminal propeptide of type I procollagen and the C-terminal cross-linked telopeptide of type I collagen (ICTP). Multivariate regression analysis showed that menopausal status (P=0.007) and metastatic bone lesions (P=0.001) affected bone marker levels. When considering post-menopausal women, the only subset in which bone metabolism marker behaviour could be reliably investigated, we found a high degree of overlap in marker distribution for scan-positive and scan-negative patients. Discrimination between scan-negative and scan-positive patients based on the above markers, taken singly or jointly, was assessed by means of logistic discriminant analysis. The best discrimination was achieved with BAP, closely followed by ICTP. BAP and ICTP together gave a slight improvement over the use of the two markers separately. However, even in this case the degree of discrimination was poor and its clinical utility was limited. In fact, to achieve a specificity of 95%, the sensitivity of the test was about 20%; conversely, with a sensitivity of 95%, the specificity was below 10%. In conclusion, based on our findings, we believe that blood levels of the investigated markers cannot replace bone scintigraphy in the follow-up of breast cancer patients for the early detection of bone metastases. PMID- 9371867 TI - Gamma camera imaging of osseous metastatic lesions by strontium-89 bremsstrahlung. AB - The aim of this study was to optimise the parameters affecting the Bremsstrahlung scintigraphy of patients injected with strontium-89 chloride. The parameters considered were : (1) instrumental detection efficiency, and (2) tissue attenuation factor for 89Sr calibrated sources, which permit quantitative evaluation of the activity in a given bone lesion. Some typical examples of in vivo 89Sr imaging are presented to illustrate the clinical utility of the imaging procedure developed by us, which is implemented in our department for all patients treated with 89Sr chloride. PMID- 9371869 TI - Parametric imaging of patient pharmacokinetics. AB - This paper presents an approach to extracting patient pharmacokinetic information from a set of longitudinal scintigraphic images and representing the kinetic information in parametric image form. In this approach, three or four pairs of simultaneously acquired anterior and posterior images, for internal dosimetry with iodine-131, are obtained at 24-h intervals. Each pair of anterior and posterior images is converted to a "conjugate-view" image. The sequential conjugate-view images are then spatially registered to each other using a symmetric phase-only matched filter technique. With the registered images, the value at each pixel location, over time, is fitted to a monoexponential function. The resulting decay constant and intercept parameters are then represented as "decay-constant" and "intercept" images. Further analytical integration of the exponential function results in a "cumulated-activity" image. Phantom studies demonstrated that the proposed method is accurate and reliable in the registration and kinetic data extraction of the longitudinal images. Clinical application of the approach to patients with thyroid carcinoma showed that regions of rapid uptake or clearance that would not otherwise be highlighted were easily identified and some regions with unexpected kinetics were observed. It is concluded that decay-constant, intercept, and cumulated-activity images provide a rapid and comprehensive visual assessment of patient pharmacokinetics. The technique may have a greater impact on the care of patients with extensive and distributed disease. PMID- 9371868 TI - Development of a radiopharmaceutical activity schedule for technetium-99m dimercaptosuccinic acid in children based on image quality criteria. AB - The aim of this study was to determine an activity schedule (amount of administered activity in relation to body weight) for technetium-99m dimercaptosuccinic acid examinations in children, from information present in renal scintigraphic images. Scans from 48 children (5 weeks to 14.8 years old) were graded for image quality according to the clarity of both kidney outline and internal structure. Numerical image data (kidney and background counts, signal-to noise ratio) were associated with these subjective gradings to formulate three criteria, specifying the required values of the above-measured parameters to yield optimum grades of image quality. When applied to derived functions, a kidney uptake of 20% was required to satisfy the criterion based on the signal-to noise ratio. Using this value with the other two criteria predicts the form of the weight-dependent activity schedule as a function of imaging time. Examples of schedules for imaging times of 300 and 600 s are compared with a schedule based on surface area. PMID- 9371870 TI - Characteristics and biological behaviour of 99mTc-labelled hydroxyacetyltriglycine, a potential alternative to 99mTc-MAG3. AB - Substitution of the oxidation-sensitive thiol function of mercaptoacetyltriglycine (MAG3) by a hydroxyl group yields a tetraligand (hydroxyacetyltriglycine or HAG3) which is almost insensitive to oxidation and has the advantage over MAG3 that it can be stored safely without protection of the alcohol function. We found that deprotected HAG3 could be directly labelled at alkaline pH (pH>/=11.5) and room temperature in high yield (>95%). Results of electrophoresis experiments suggested a comparable structure for 99mTc-HAG3 and 99mTc-MAG3, namely binding of an oxotechnetium(V)core via three deprotonated amides and a deprotonated hydroxyl group. Biodistribution studies in mice at 10 min and 30 min p.i. showed a slightly higher urinary excretion, a faster renal transit and a significantly lower hepatobiliary handling for 99mTc-HAG3 than for 99mTc-MAG3. In a baboon, the 1-h plasma clearance of 99mTc-HAG3 was clearly higher than that of 99mTc-MAG3. Its plasma protein binding was in the same order as that of Hippuran and much lower than that of 99mTc-MAG3. Evaluation in a human volunteer confirmed the favourable biological characteristics of 99mTc-HAG3, namely a rapid renal excretion, a high 1-h plasma clearance and a negligible hepatobiliary handling. The results indicate that 99mTc-HAG3 may be an easy-to prepare and practical substitute for 99mTc-MAG3 with improved renal excretion characteristics. PMID- 9371871 TI - Radiation dose to technicians per nuclear medicine procedure: comparison between technetium-99m, gallium-67, and iodine-131 radiotracers and fluorine-18 fluorodeoxyglucose. AB - The aim of this study was to determine the non-extremity gamma dose received by a technician while performing an ordinary nuclear medicine procedure or a static (i.e. without blood sampling) fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) study. The dose per patient was measured by means of a commercial electronic pocket Geiger Mueller dosimeter, worn in the upper left pocket of the overalls. This was previously tested by exposure to known point sources of technetium-99m, gallium-67, iodine-131 and fluorine-18 in the air. A further test was performed with 99mTc, 131I and 18F sources inserted in a water phantom to simulate the condition of high scattering degradation of the primary radiation due to the patient's tissues. Subsequently, the dose was measured by two technicians for a total of 314 clinical cases, covering the most common nuclear medicine procedures, including 44 static, two-level FDG PET studies with repositioning of the patient on the couch between the transmission and the emission scan and seven whole-body PET studies. The dose read by the dosimeter was corrected for environmental background and for detector efficiency measured with sources in the air. For a limited subset of cases, the time spent close to patients was also measured. Doses were then estimated by a crude non-absorbing point source approximation and by using experimental dose rates. A comparison between experimental and estimated doses, as well as with previously published data, completed the work. For most of the conventional procedures, the measured dose per procedure proved to be within the range 0.2-0.4 microSv, except for equilibrium angiocardioscintigraphy (1.0+/-0.5 microSv) and 99mTc-sestamibi single-photon emission tomography (1. 7+/-1.0 microSv). Comparison with data published in the last 20 years shows that our values are generally lower. The current more favourable working conditions are a result of technological improvements (for instance two-head gamma cameras capable of whole-body studies), and safer shielding and distance from patients. Two-level PET gave 11.5+/-4.4 microSv and whole-body PET 5.9+/-1.2 microSv. In a subset of patients these values could be subdivided into the separate contributions from each phase of the procedure. They were: 0.11+/-0.04 microSv for daily quality assurance, 2.9+/-3.0 microSv for two transmission scans, 0.3+/-0.1 microSv for syringe preparation, 2.8+/-1.8 microSv for injection and escorting the patient to the waiting room, 1.7+/-1.5 microSv for a whole-body emission scan, 7.7+/-5.2 microSv for two emission scans, and 0.8+/-0. 2 microSv for patient departure. The higher value from PET by comparison with conventional procedures is attributable to the higher specific gamma constant of 18F, as well as the longer time required for accurate positioning. PMID- 9371872 TI - Simultaneous emission transmission tomography using technetium-99m for both emission and transmission. AB - This phantom study investigates whether attenuation maps from transmission data degraded by increased noise from subtraction of emission counts can still provide useful attenuation correction in the regular and obese chest. Technetium-99m was used for both emission and transmission on a triple head simultaneous emission transmission tomography (Tc-Tc SETT) system. Fanbeam transmission counts were computed by subtracting emission counts estimated from the two parallel collimator heads. Radioactive decay was used to simulate organ counts from injections of 900 and 400 MBq sestamibi for regular and obese chest sizes. Line source activity was 350 MBq. Control attenuation maps were obtained with no emission activity. Noise control included catering for negative and zero transmission counts, pre-filtering and segmentation of mu maps. Pre-filtering was tried before and after subtraction and before and after setting negative pixels to zero. Mean+/-SD count/pixel at the heart in anterior transmission projections was typically 33+/-18 for the regular and 1+/-7 for the obese chest. For the obese chest, pre-filtering before resetting negative counts best preserved mean mu in soft tissue and lung. Tc-Tc SETT mu mean+/-SD for the regular chest were 0.144+/-0.012 and 0.058+/-0.004 for soft tissue and lung and for the obese chest, 0.152+/-0.075 and 0.059+/-0.017. The accuracy of the Tc-Tc SETT bullseye plots for the regular chest was the same as with control map attenuation correction and 3 times better than with no correction. For the obese chest it was as good as with control map correction only if mu map segmentation was applied. Tc-Tc SETT soft tissue and lung mu in 28 patient studies indicated that segmentation is practical for a wide range of chest sizes. Tc-Tc SETT on a triple-head system offers an accurate, inexpensive method of attenuation correction for the majority of chest sizes. PMID- 9371873 TI - Evaluation of optimally designed planar-concave collimators in single-photon emission tomography. AB - The imaging properties of optimally designed planar-concave (PC) collimators were evaluated by means of Monte Carlo simulations. The evaluation was done with respect to total system spatial resolution and the overall image noise distribution in single-photon emission tomography. The results showed that the non-isotropy with PC collimators, assessed by the ratio of the full-width at half maximum in the radial and tangential directions, was reduced by about 60% as compared with a conventional parallel-hole collimator for sources located 200 mm away from the centre of rotation. Furthermore, the image noise distribution along the object radius became more uniform when the curved collimator was used. The maximum increase in noise due to use of the curved collimator was about 45% close to the edge of the phantom, where the hole length was about 3 times longer. We also showed with Monte Carlo simulations that the spatial resolution of the lateral cortex when using the curved collimator was significantly improved due to improved radial resolution. PMID- 9371875 TI - Spatial transformation during 3D reconstruction in positron emission tomography. AB - Spatial transformations of positron emission tomographic data for aligning images or transforming to standard anatomical space are usually performed with reconstructed images. However, they can also be performed during the reconstruction process, thereby interpolating the raw data fewer times. We investigated the performance of spatial transformations during reconstruction, implemented it in a standard 3D reconstruction algorithm, and tested it on phantom and patient H215O activation studies for the application of aligning both transmission and emission scans. Performing the transformations during reconstruction was shown to be equivalent to performing the transformations with reconstructed images for this particular application. PMID- 9371874 TI - Registration of dynamic dopamine D2 receptor images using principal component analysis. AB - This paper describes a novel technique for registering a dynamic sequence of single-photon emission tomography (SPET) dopamine D2 receptor images, using principal component analysis (PCA). Conventional methods for registering images, such as count difference and correlation coefficient algorithms, fail to take into account the dynamic nature of the data, resulting in large systematic errors when registering time-varying images. However, by using principal component analysis to extract the temporal structure of the image sequence, misregistration can be quantified by examining the distribution of eigenvalues. The registration procedures were tested using a computer-generated dynamic phantom derived from a high-resolution magnetic resonance image of a realistic brain phantom. Each method was also applied to clinical SPET images of dopamine D2 receptors, using the ligands iodine-123 iodobenzamide and iodine-123 epidepride, to investigate the influence of misregistration on kinetic modelling parameters and the binding potential. The PCA technique gave highly significant (P<0.001) improvements in image registration, leading to alignment errors in x and y of about 25% of the alternative methods, with reductions in autocorrelations over time. It could also be applied to align image sequences which the other methods failed completely to register, particularly 123I-epidepride scans. The PCA method produced data of much greater quality for subsequent kinetic modelling, with an improvement of nearly 50% in the chi2 of the fit to the compartmental model, and provided superior quality registration of particularly difficult dynamic sequences. PMID- 9371876 TI - Effect of deadtime loss on quantitative measurement of cerebral blood flow with technetium-99m hexamethylpropylene amine oxime. AB - Deadtime count loss may cause error in quantitative measurements with a gamma camera. We evaluated the effect of deadtime loss on the measurement of cerebral blood flow (CBF). Radionuclide angiography with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) was performed in 20 patients. A reference source was placed on the periphery of the detector to monitor deadtime loss, and CBF was calculated based on the data of radionuclide angiography with and without deadtime correction. In ten patients injected with 1110 MBq of the tracer, the CBF value without correction was 9.9%+/-1.8% higher than that with correction. This shows that deadtime loss may cause significant overestimation. The difference between CBF values obtained with and without correction was smaller in ten patients with an injected dose of 370 MBq (3.0%+/-1.2%). These results suggest a substantial effect of deadtime loss on CBF as measured by radionuclide angiography and 99mTc-HMPAO. PMID- 9371877 TI - Human biodistribution and dosimetry of iodine-123-fluoroalkyl analogs of beta CIT. AB - Two new N-omega-fluoroalkyl analogs of [123I]2beta-carbomethoxy-3beta-(4 iodophenyl)tropane ([123I]beta-CIT), the fluoroethyl and fluoropropyl compounds ([123I]FE-CIT and [123I]FP-CIT, respectively), have been shown to have faster kinetics and better selectivity for the dopamine transporter than [123I]beta-CIT. We examined the organ biodistribution and radiation safety of these two compounds in six healthy volunteers who received an injection with each of the two compounds 2 weeks apart. Data were obtained on the Strichman 860 whole-body scanner. Transmission scans were obtained in all subjects prior to the injection of the radiotracer with a line source and used to derive organ-specific attenuation correction factors. Whole-body planar images were acquired every hour for the first 6 h, and at 24 h. Attenuation-corrected regional conjugate counts were converted into units of activity using a calibration factor obtained for each subject by dividing whole-body conjugate decay-corrected counts from the first acquisition by the injected activity. Radiation dose estimates were on average higher for [123I]CIT-FE than for [123I]CIT-FP, with the lower large intestine receiving the highest exposure: 0.15+/-13% mGy/MBq (mean +/-COV) and 0.12+/-14% mGy/MBq for [123I]FE-CIT and [123I]FP-CIT, respectively, followed by the upper large intestine and the spleen. PMID- 9371878 TI - Technetium-99m methoxyisobutylisonitrile single-photon emission tomography in hepatocellular carcinoma. AB - Nine lesions in eight patients with hepatocellular carcinoma (HCC) were studied using single-photon emission tomography (SPET) and technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) to evaluate the pattern of uptake of 99mTc MIBI in the lesions and the relation between the uptake pattern and the histopathology of HCC. All the lesions were diagnosed as HCC by percutaneous needle biopsy. Four of the nine lesions showed positive uptake of 99mTc-MIBI, while the other five showed negative uptake. All of the lesions which showed positive uptake were of the compact type. Of the five lesions that showed negative uptake, four were of the trabecular type while one was of the compact type. These results suggest that the patterns of 99mTc-MIBI accumulation in HCC are divided into positive and negative types and that these uptake patterns are associated with the tissue structure of HCC. PMID- 9371879 TI - The value of quantitative gallium-67 single-photon emission tomography in the clinical management of malignant external otitis. AB - Malignant external otitis (MEO) is a severe infectious disorder usually caused by Pseudomonas aeruginosa, which most frequently affects diabetic patients. Due to its rarity, the diagnosis of MEO is often not made promptly. Extension into deeper structures or chronic osteomyelitis may occur without signs of infection on local clinical examination. Of the imaging techniques, magnetic resonance imaging provides a fairly adequate picture of the spread of the disease, but, as with computed tomography (CT) scanning and bone scintigraphy, the images remain unchanged for a long time after disease regression. The objective of this study was to establish whether quantitative gallium-67 single-photon emission tomography (SPET) represents an accurate method for the assessment of infection and, moreover, for the monitoring of therapeutic effect. Eight patients (five males, three females) with the clinical diagnosis of MEO were studied. In three patients antibiotic treatment was prolonged for several weeks because visual analysis of gallium scintigraphy still showed slightly increased uptake in the affected area on the first follow-up scan. In one patient, it was decided to stop antibiotic treatment despite a slight increase in uptake on the second follow-up scan. Lesion to non-lesion (L/NL) ratios obtained from 67Ga SPET images at initial diagnosis and during follow-up were assessed in correlation with clinical and biochemical data and with the results of CT scans. In addition to a raised erythrocyte sedimentation rate (ESR), all patients showed increased uptake on the affected side, with L/NL ratios ranging from 1.4 to 3.6 at the time of diagnosis. CT scans failed to demonstrate abnormalities in four patients. Including four scans demonstrating slightly increased uptake in the affected area, L/NL ratios after 6-8 weeks of antibiotic treatment were 1.0+/-0.1. Despite a persistently elevated ESR in the majority of patients, none of them demonstrated local recurrence or complications during follow-up. In all patients, leucocyte count was within the normal range throughout the course. No relation was found between the slightly increased uptake on the follow-up scans and surgical treatment. It is concluded that in addition to the visual analysis of 67Ga SPET imaging, L/NL ratios should be calculated for a more accurate assessment of disease activity in MEO. Despite visually slightly increased uptake, L/NL ratios of 1.0+/-0.1 during follow-up are highly indicative of complete recovery, regardless of ESR values or leucocytosis. CT scans are of little value for diagnosis or for monitoring of therapeutic effect. PMID- 9371880 TI - The placebo effect. AB - The placebo effect will have a growing importance in the field of nuclear medicine as the potentials for palliative therapy with internal sources are realized. It is important for nuclear medicine physicians and their colleagues to be familiar with the role of placebo responses in clinical trials, especially when such trials involve the subjective assessment of pain. A summary of the literature on the placebo effect in pain studies is presented in which traditional values for placebo responses are contrasted with more current thinking in the field. The few published double-blind studies of pain relief after treatment with radiotherapeutic agents are summarized specifically with respect to their cited placebo response. PMID- 9371882 TI - A Saccharomyces cerevisiae mutant defective in the kinesin-like protein Kar3 is sensitive to NaCl-stress. AB - Several mutants of Saccharomyces cerevisiae showing poor growth in the presence of elevated concentrations of NaCl were isolated to identify genes involved in the osmo-stress response. One of these mutants (WAY.5-4A-11; osr11) which showed a clear 2:2 segregation of the salt-stress phenotype upon tetrad analysis when crossed to a wild-type strain has been characterised. The mutation responsible for poor growth under salt-stress was recessive. The corresponding gene was cloned by complementation of the mutant phenotype and a 3.5-kb fragment was isolated. The sequence of this fragment matched that of KAR3, a gene previously identified to be involved in karyogamy and mitosis. Allelism of OSR11 to KAR3 was confirmed by tetrad analysis, and disruption mutants showed the same NaCl phenotype as the original osr11 mutation. The disruption mutant was more sensitive to high sucrose concentrations than the original mutant was to high glucose concentrations. In a different genetic background (W303-1A), the kar3 disruptants were less sensitive to osmo-stress than the WAY.5-4A strain. Heat stress, nitrogen-starvation and cultivation on ethanol failed to affect the growth of osr11 and kar3 mutants, pointing to a possible specific involvement of KAR3 in the osmotic-stress response. Microscopic studies showed that cell division of the kar3 mutants was impaired and NaCl-stress conditions aggravated the phenotype. PMID- 9371881 TI - Arabidopsis thaliana RAD6 homolog AtUBC2 complements UV sensitivity, but not N end rule degradation deficiency, of Saccharomyces cerevisiae rad6 mutants. AB - AtUBC2 of Arabidopsis thaliana encodes a structural homolog of the RAD6 gene of Saccharomyces cerevisiae with approximately 65% identical amino acids. Like structural homologs from other organisms, AtUBC2 lacks the carboxyl-terminal extension of mostly acidic amino acids which is present in Rad6p. AtUBC2 was expressed in S. cerevisiae rad6 mutants. It was found to partially complement the UV sensitivity and reduced growth rate of rad6 mutants at elevated temperatures. AtUBC2 however, has no apparent influence on the degradation of N-end rule substrates in the heterologous host. PMID- 9371884 TI - 6-N-hydroxylaminopurine (HAP)-induced accumulation of variability in haploid and diploid strains of Aspergillus nidulans. AB - Haploid and diploid strains of Aspergillus nidulans have been repeatedly treated with the strong mutagen 6-N-hydroxylaminopurine (HAP) which causes only base substitutions. An enormous amount of variability may be rapidly accumulated in haploid or diploid strains of A. nidulans. In particular, in the diploids the analysis of the results shows that after 12 cycles of treatment the conidia differ from each other for about ten recessive lethals and therefore probably for several hundreds of mutations. The viability of the heterozygous multiply mutant diploids is not appreciably different from that of untreated controls. In the diploid strains the accumulated variability was very high. The treatment of a haploid strain during vegetative growth also caused a strong accumulation of mutations, even though deleterious, because they can be maintained in the heterokaryotic condition. PMID- 9371883 TI - Molecular characterization of a novel fission yeast gene spUAP2 that interacts with the splicing factor spU2AF59. AB - A protein essential for pre-mRNA splicing, the U2 auxiliary factor (U2AF), is composed of a large and small subunit. Previously we cloned and characterized both subunits, spU2AF59 and spU2AF23, from fission yeast. We now report a novel U2AF-associated-protein, spUAP2, which interacts with both subunits. SpUAP2 contains a classical and a degenerate RNA recognition motif (RRM), both of which are required for interaction with spU2AF59. Interaction also requires the arginine/serine-rich region and the first RRM of spU2AF59. A null allele of the gene for spUAP2 is lethal. PMID- 9371885 TI - Parental and novel copies of the mitochondrial orf25 gene in the hybrid crop plant triticale: predominant transcriptional expression of the maternal gene copy. AB - Triticale, an intergeneric hybrid crop-plant, is generated when female wheat lines are fertilised with pollen from rye. We have investigated the mitochondrial DNA organisation and the expression of a total of 11 different triticale genotypes, varying in their nuclear and cytoplasmic backgrounds. In Southern hybridisations using probes homologous to the upstream flanking sequences, mtDNA fragments characteristic of both wheat and rye mtDNA can be detected in all triticale lines analysed. In addition, clones isolated fom a triticale lambda library exhibit either a maternal-like or paternal-like organisation of the orf25 gene region. By PCR cloning, four different orf25 gene copies were identified in triticale, three of which correspond to maternal (85%) or paternal (12%) orf25 sequences. Three percent of all clones represent a novel type, that might have arisen by homologous recombination. Although these data suggest biparental inheritance of mtDNA in wheat/rye crosses, paternal-like gene copies can also be detected in maternal wheat mitochondria. Their stoichiometry as assayed by competitive PCR is about 0.1% of total orf25 gene copies. The high abundance of paternal-like sequences in the F1 hybrid might therefore be due to either the transmission of rye mtDNA in the intergeneric cross and/or the amplification of sequences in triticale that persist in sub-stoichiometric amounts in wheat. These data suggest that amplification and recombination of sub-genomic mitochondrial molecules are affected by different nuclear genotypes. Interestingly, sequence analysis of triticale RT-PCR clones indicates a selective transcription of maternal-like orf25 gene copies in triticale. Mitochondrial gene expression may therefore possess mechanisms to compensate for the variation of mtDNA organisation. PMID- 9371886 TI - An intact F1ATPase alpha-subunit gene and a pseudogene with differing genomic organization are detected in both male-fertile and CMS petunia mitochondria. AB - The gene copies for the alpha-subunit of the mitochondrial F1ATPase (atpA) were isolated and characterized in both male-fertile and cytoplasmic male sterile (CMS) petunia. Two copies, an intact gene and a truncated gene, were detected in both cytoplasms. The accumulated data, based upon a comparison of the sequences (the open reading frames as well as the 5' and 3' flanking regions) of the two atpA copies, both in male-fertile and CMS Petunia, indicate that: (1) they differ in their genomic organization and (2) a common progenitor cytoplasm, containing two copies of an intact atpA sequence, served as the origin for the atpA copies of the fertility and CMS-inducing cytoplasms. Homologous recombination through the progenitor intact atpA sequences is assumed to have caused the rearrangement in the 3' portion of the atpA open reading frame and the generation of the truncated atpA gene. It is thus suggested that the atpA pseudogenes, in both male fertile and CMS cytoplasms, originated from a common progenitor atpA pseudogene sequence. PMID- 9371887 TI - Evolutionary aspects of "chloroplast-like" trnN and trnH expression in higher plant mitochondria. AB - Two identical "chloroplast-like" tRNAAsn genes, trnN1 and trnN2, have been identified in the potato (Solanum tuberosum) mitochondrial genome. The flanking sequences of trnN1 are unrelated to the corresponding authentic potato chloroplast regions, whilst those of trnN2 are very similar to the chloroplast sequences. The trnN1 copy is present in the mitochondrial genome of various plants whereas the second copy, trnN2, is absent from all the other plant genomes studied so far. Interestingly, both trnN copies are expressed in potato mitochondria. Sequences flanking the chloroplast-like tRNAHis gene (trnH), present as a single copy in the potato mitochondrial DNA, are unrelated to the corresponding chloroplast sequences, whereas chloroplast-derived sequences have been maintained in the vicinity of the maize chloroplast-like mitochondrial trnH gene. However, both the potato and the maize trnH are expressed in mitochondria. PMID- 9371888 TI - Characterization of the mitochondrial cytochrome b gene from Venturia inaequalis. AB - A new class of agricultural fungicides derived from the group of antifungal strobilurins acts as specific respiration inhibitors by binding to mitochondrial cytochrome b. The cytochrome b gene was cloned and sequenced from the mitochondrial genome of Venturia inaequalis, the causal agent of apple scab. The gene was 10.65 kbp in size and contained seven exons and six introns. The exons encoded a protein of 393 amino acids. Comparison of the deduced amino-acid sequence with cytochrome b proteins from other fungi revealed highest homologies to the respective proteins of Aspergillus nidulans, Podospora anserina and Neurospora crassa. All amino acids of the V. inaequalis cytochrome b at positions altered in mutants of Saccharomyces cerevisiae resistant to strobilurins, and other fungi with reduced sensitivities to strobilurins, were identical to wild type isolates of several fungi. The cloning and characterization of the V. inaequalis cytochrome b gene is the initial step in the assessment of resistance risks inherent to the strobilurin fungicides. PMID- 9371889 TI - Isolation of the glucose oxidase gene from Talaromyces flavus and characterisation of its role in the biocontrol of Verticillium dahliae. AB - The glucose oxidase gene from the biocontrol fungus Talaromyces flavus has been isolated and shown to be only 64% identical at the amino-acid sequence level to the similar enzyme from Aspergillus niger. A transformation system has been developed for both T. flavus and the related T. macrosporus and has been used to create Talaromyces spp. which either over-express or are deficient in glucose oxidase. In vitro inhibition experiments on Verticillium dahliae using culture filtrates from these transformants indicates that secreted glucose oxidase is responsible for a large part of the growth inhibition of V. dahliae microsclerotia and hyphae by T. flavus, although other inhibitory compounds may also play a role. In pot trials with cotton plants, both Talaromyces species had some biocontrol activity, but there was no significant difference in the incidence of Verticillium wilt with either the presence or absence of glucose oxidase activity in the biocontrol fungus. Under the experimental conditions used, insufficient glucose is presumably present in the soil around cotton roots to generate sufficient hydrogen peroxide to inhibit V. dahliae and the observed biocontrol activity must be attributed to other factors. PMID- 9371891 TI - CAG repeats in SCA6. Anticipating new clues. PMID- 9371890 TI - Attacking migraine headache from beginning to end. PMID- 9371892 TI - Implicit memory. Knowledge without awareness. PMID- 9371893 TI - Krabbe continuum or clinical conundrum? PMID- 9371895 TI - Crisis in the Presidency. The physician's role in assessing official capacity. PMID- 9371894 TI - Quality improvement in neurology residency programs. Report of the Quality Improvement Committee of the Association of University Professors of Neurology. AB - The neurology residency programs in the United States are facing a crisis of quality. The Association of University Professors of Neurology (AUPN) approved the Quality Improvement Committee to examine this situation and make recommendations, which have been accepted by the AUPN. The recommendations are (1) that the educational goals of neurology residency training be dissociated from patient-care needs in academic medical centers and (2) that minimum levels of quality be applied to residents in neurology residency programs and to these programs themselves. These minimum criteria should include minimum educational criteria for entry into the program, minimum criteria for advancement from one year to the next in the program, and minimum criteria for performance of the graduates of neurology residency programs for program accreditation. The implementation of these recommendations will require a shift of funding of the care of indigent patients from the graduate medical education budget to direct patient-care sources. These recommendations will significantly improve the quality of neurologists and neurologic care in the United States. PMID- 9371896 TI - Optimizing the dose of zolmitriptan (Zomig, 311C90) for the acute treatment of migraine. A multicenter, double-blind, placebo-controlled, dose range-finding study. The 017 Clinical Trial Study Group. AB - This study investigated the efficacy of zolmitriptan (Zomig, formerly 311C90) in acute migraine therapy. Patients with a history of migraine were randomized in a double-blind, multicenter, placebo-controlled, dose range-finding study of oral zolmitriptan 1, 2.5, 5, or 10 mg versus placebo for the treatment of a severe or moderate migraine headache. Patients with persistent or recurrent headache 4 to 24 hours after the initial dose, who did not take escape medication, were eligible to receive a second blinded dose of either zolmitriptan or placebo. Of 1,144 patients treated, 999 evaluable patients completed the study. The headache response rates with zolmitriptan doses > or = 2.5 mg were 44 to 51% at 1 hour, 65 to 67% at 2 hours, and 75 to 78% at 4 hours (all significantly superior to placebo). Also, zolmitriptan effectively relieved migraine-associated symptoms such as nausea, photophobia and phonophobia, and reduced activity impairment. Rates of headache recurrence, headache persistence, and use of escape medication were lower with zolmitriptan doses > or = 2.5 mg than with placebo. In patients with persistent or recurrent headache, a second zolmitriptan dose effectively treated both headache and nonheadache symptoms. Zolmitriptan was well tolerated, with a lower incidence of adverse events being reported with doses < or = 2.5 mg than with those > or = 5 mg. Zolmitriptan is a well tolerated and effective acute migraine therapy providing rapid relief of migraine headache within 1 hour. A clear dose-response relationship between efficacy and tolerability suggests that 2.5 mg is the optimal initial dose for the acute treatment of a migraine attack. PMID- 9371897 TI - Clinical efficacy and tolerability of 2.5 mg zolmitriptan for the acute treatment of migraine. The 042 Clinical Trial Study Group. AB - Previous studies demonstrated that zolmitriptan at doses of 1 to 25 mg was highly effective in treating acute migraine attacks. The 2.5-mg dose had a favorable therapeutic effect with high efficacy and good tolerability. The objective of this study was to further evaluate the efficacy of a single 2.5-mg dose of zolmitriptan (Zomig, formerly known as 311C90) for acute treatment of a single moderate or severe migraine attack. The study was a randomized, double-blind, placebo-controlled clinical trial. Female and male patients, 12 to 65 years old, with migraine (with or without aura) for > or = 1 year, one to six migraines per month, and age at onset < 50 years were included; 327 patients were screened and randomized to receive either zolmitriptan (n = 219) or placebo (n = 108). Patients treated a single moderate or severe migraine headache with 2.5 mg zolmitriptan or placebo and recorded clinical efficacy and adverse events on a diary form. Headache response at 2 hours was 62% for zolmitriptan compared with 36% for placebo (p < 0.001); at 4 hours, headache response was 70% with zolmitriptan and 37% with placebo (p < 0.001). Headache recurrence in patients treated with 2.5 mg zolmitriptan was 22% (versus placebo 30%). The headache response at 4 hours, pain-free rate, and response rate of nonheadache symptoms favored zolmitriptan over placebo. No serious adverse events were associated with zolmitriptan treatment. A 2.5-mg dose of zolmitriptan is clinically effective and well tolerated for the acute treatment of migraine. PMID- 9371898 TI - Sumatriptan nasal spray for the acute treatment of migraine. Results of two clinical studies. AB - BACKGROUND: Sumatriptan nasal spray may be particularly useful for patients whose nausea and vomiting preclude them from using oral migraine medication or for patients who prefer not to use an injectable migraine medication. The objective of this study was to evaluate in two clinical studies the efficacy and tolerability of the intranasal form of sumatriptan in the acute treatment of a single migraine attack. International Headache Society-diagnosed adult migraineurs in two randomized, double-blind, parallel-group, multicenter studies (n = 409 and 436) used sumatriptan nasal spray 20 mg, 10 mg, or placebo (2:1:1) for the acute treatment of a single migraine attack at home. Predose and at predetermined postdose intervals, patients recorded headache severity (none, mild, moderate, severe); time to meaningful relief; clinical disability (none, mildly impaired, severely impaired, bed rest required); presence/absence of nausea, photophobia, and phonophobia; and the occurrence of adverse events. Two hours postdose in the two studies, moderate or severe baseline pain was reduced to mild or none in 62 to 63% of patients treated with sumatriptan 20 mg, 43 to 54% of patients treated with sumatriptan 10 mg, and 29 to 35% of placebo-treated patients (p < 0.05 20 mg versus placebo for both studies and 10 mg versus placebo for study 1). Onset of relief relative to placebo began as early as 15 minutes postdose (sumatriptan 20 mg, study 2). Clinical disability at 2 hours postdose was reported as mildly impaired or normal in 72 to 74% of patients treated with sumatriptan 20 mg, 56 to 68% of patients treated with sumatriptan 10 mg, and 47 to 58% of placebo-treated patients (p < 0.05 20 mg versus placebo for both studies). Similar efficacy rates were observed for nausea, photophobia, and phonophobia. The most common adverse event in the active treatment groups was disturbance of taste (bad, bitter, or unpleasant taste). Aside from this event, the pattern and incidence of adverse events did not differ among treatment groups. From these results we determined that sumatriptan nasal spray is a rapidly effective, well-tolerated migraine treatment. The 20-mg dose was effective in treating the entire migraine symptom complex, and the 10-mg dose was less consistently effective. PMID- 9371899 TI - A new locus for hemiplegic migraine maps to chromosome 1q31. AB - A single familial hemiplegic migraine locus has been previously mapped to 19p13.1 and associated with mutations in a calcium channel gene (CACNL1A4). We describe a new 39-member four-generation family from Wyoming of German-Native American descent with autosomal dominant familial hemiplegic migraine that is not linked to the chromosome 19p locus. Affected individuals showed a stereotypic pattern of migrainous headache associated with hemisensory and hemiparetic attacks, without other headache types. Eighty-three percent reported minor head trauma as a trigger for individual attacks. Seventy-two percent reported other typical migraine triggers for the attacks. Attack frequency decreased with age and the overall course was benign. Genetic linkage studies of this family found strong evidence for the disease gene in this family being located at chromosome 1q31. Multipoint analysis showed lod scores > 3 in a 44-cm region flanked by D1S158 and D1S2781, using 80% penetrance and a phenocopy rate of 1/50. Haplotype and multipoint analysis, including flanking markers, suggested incomplete penetrance and variable expressivity of the disease. A single affected patient who reports atypical symptoms including daily headaches likely represents a phenocopy. This new locus for hemiplegic migraine suggests that mutations of additional calcium channels in the region may cause the disease. PMID- 9371900 TI - Spinocerebellar ataxia type 6. Molecular and clinical features of 35 Japanese patients including one homozygous for the CAG repeat expansion. AB - Spinocerebellar ataxia type 6 (SCA6) is a newly classified autosomal-dominant cerebellar ataxia (ADCA) associated with CAG repeat expansion. We screened 111 patients with cerebellar ataxia for the SCA6 mutation. Of these, 35 patients were found to have expanded CAG repeats in the SCA6 gene, indicating that second to SCA3, SCA6 is the most common ADCA in Japan. Expanded alleles ranged from 21 to 29 repeats, whereas normal alleles had seven to 17 repeats. There was no change in the CAG repeat length during meiosis. The age at onset was inversely correlated with the repeat length. The main clinical feature of the 35 patients with SCA6 was slowly progressive cerebellar ataxia; multisystem involvement was not common. The 35 patients included nine cases without apparent family history of cerebellar ataxia. The sporadic cases had smaller CAG repeats (21 or 22 repeats) and a later age at onset (64.9 +/- 4.9 years) than the other cases with established family history. We also identified one patient who was homozygous for the SCA6 repeat expansion. The homozygote showed an earlier age of onset and more severe clinical manifestations than her sister, a heterozygote carrying an expanded allele with the same repeat length as the homozygote. This finding suggests that the dosage of the CAG repeat expansion plays an important role in phenotypic expression in SCA6. PMID- 9371901 TI - Clinical and molecular features of spinocerebellar ataxia type 6. AB - The mutation involved in spinocerebellar ataxia type 6 (SCA6) is a small CAG expansion in the alpha-1A subunit of the voltage-dependent calcium channel gene. We looked for this mutation in 91 families with autosomal-dominant cerebellar ataxias and found that SCA6 is a minor locus in our series (2%) and is rare in France (1%). Furthermore, we did not detect the SCA6 mutation on 146 sporadic cases with isolated cerebellar ataxia or olivopontocerebellar atrophy. The normal and expanded alleles ranged from 4 to 15 and 22 to 28 CAG repeats, respectively, and age at onset was correlated to CAG repeat length (r = -0.87). In contrast with other SCA, the expanded allele was stable during transmission. Clinically, SCA6 patients (n = 12) presented with moderate to severe cerebellar ataxia with a lower frequency of associated signs compared with other SCA and a mean age at onset of 45 +/- 14 years (range, 24 to 67). MRI showed extensive cerebellar atrophy but not of the brainstem or cerebral cortex. PMID- 9371902 TI - Spinocerebellar ataxia type 6. Frequency of the mutation and genotype-phenotype correlations. AB - Spinocerebellar ataxia type 6 (SCA6) is the most recently identified mutation causing autosomal-dominant cerebellar ataxia without retinal degeneration (ADCA). The SCA6 mutation is allelic with episodic ataxia type 2 (EA-2), but the two differ clinically because of the presence of progressive, rather than episodic, ataxia in SCA6. SCA6 accounts for 12% of families with ADCA in an ethnically heterogeneous population of patients. Clinical examination, quantitative eye movement testing, and imaging data show that the brainstem is normal in most patients with SCA6, especially within the first 10 years of symptoms. Most patients show progressive ataxia from the onset, but several patients show an episodic course resembling EA-2. Thus, SCA6 mutations not only account for patients with ADCA I and ADCA III phenotypes but also for some patients presenting with episodic features that are typical for EA-2. Interestingly, a compound heterozygote for the SCA6 expansion manifested an earlier onset and more rapid course than family members with the same larger expanded allele. PMID- 9371903 TI - Gene locus FPD1 of the dystonic Mount-Reback type of autosomal-dominant paroxysmal choreoathetosis. AB - Genes for paroxysmal choreoathetosis have been localized to chromosomes 1p and 2q. We have reinvestigated one of the classic large autosomal-dominant pedigrees of the dystonic Mount-Reback type of paroxysmal choreoathetosis 20 years after its first assessment. These patients prefer diazepam for both prevention and treatment of attacks and did not develop addiction on an intermittent regime. Migraine occurred in a third of the patients. Genetic data localized the underlying mutation to the FPD1 locus (familial paroxysmal dyskinesia type 1) on chromosome 2q and support locus homogeneity for the Mount-Reback syndrome. The data also refine the FPD1 candidate region to 3.6 cM between the markers D2S164 and D2S2359, which may facilitate the investigation of the role of the candidate ion channel gene SLC2C. PMID- 9371904 TI - Mn SOD activity and protein in a patient with chromosome 6-linked autosomal recessive parkinsonism in comparison with Parkinson's disease and control. AB - We report Mn superoxide dismutase (SOD) protein and activity in a patient with familial autosomal recessive Lewy body-negative parkinsonism in comparison with patients with sporadic Parkinson's disease (PD) and controls. We recently proved linkage of this family with markers of chromosome 6 at 6q25.2-27, which included the Mn SOD gene. We used a novel polymorphic mutation at -9 position of the signal peptide of the Mn SOD precursor protein, which caused valine to alanine substitution. All the affected members of this family showed homozygosity for alanine, whereas nonaffected members, sporadic PD patients, and the control subjects studied showed either heterozygosity of alanine and valine or homozygosity of valine. The Mn SOD activity of this familial patient was the highest among the PD patients and the control subjects studied, and an abundant expression of Mn SOD was found in the substantia nigra. The molecular weight of Mn SOD protein by Western blotting of this patient was essentially similar to that of PD patients and the control subjects. High Mn SOD activity may constitute a genetic risk factor in this familial patient. The difference in the signal peptide sequence may affect the expression of Mn SOD within mitochondria; however, it is unlikely that loss of function type Mn SOD mutation is the cause of this familial parkinsonism. Mn SOD in sporadic PD patients was similar to that in controls. PMID- 9371905 TI - Olfactory dysfunction in familial parkinsonism. AB - Impaired olfactory function is commonly observed in idiopathic Parkinson's disease (IPD). However, it is unknown whether it is also found in familial parkinsonism. To address this issue we administered a smell test to 12 affected, three monosymptomatic, and 12 at-risk individuals from six large parkinsonian kindreds. Three kindreds exhibited an IPD phenotype and three exhibited a parkinsonism-plus syndrome (PPS) phenotype. All but one of the affected individuals had impaired olfactory function. In contrast, only five of the 12 at risk individuals had impaired olfactory function. The degree of olfactory impairment in the at-risk individuals was less severe than in the affected individuals. The difference in the degree of olfactory impairment in individuals exhibiting the IPD and the PPS phenotypes was not statistically significant. These findings suggest that olfactory dysfunction is a phenotypic characteristic of familial parkinsonism and that it is independent of the kindred phenotype. The appearance of olfactory dysfunction soon after disease onset raises the possibility that it is part of the neurodegenerative disease process. PMID- 9371906 TI - Smoking and Parkinson's disease. An age-dependent risk effect? The EUROPARKINSON Study Group. AB - We studied the association between smoking and Parkinson's disease (PD) through a case-control study. Several studies have shown an inverse association between smoking and PD. This association has been interpreted as spurious by some investigators, and as real and causal by others. Several other studies did not confirm the inverse association. We included 193 prevalent cases of PD ascertained in five European prevalence surveys that followed a two-phase design of screening and clinical examination. Each case was matched by center, age (+/- 2 years), and gender to three control subjects drawn from the same populations (N = 579). Information on smoking was obtained through direct or proxy interview. Overall, there was no association between ever smoking and PD (odds ratio = 1.1; p = 0.6). Analyses stratified by age showed that ever smoking was associated with a decreased risk of PD in the younger individuals (odds ratio = 0.4; p = 0.03) and with a significant trend of increasing risk with advancing age (p = 0.003). The risk of PD in relation to smoking is strongly modified by age; smoking may be protective in the younger cases but not in the older cases. This finding may explain the conflicting results from previous studies. PMID- 9371907 TI - High prevalence of vitamin D deficiency and reduced bone mass in Parkinson's disease. AB - Despite excessive hip fractures in patients with Parkinson's disease (PD), little is known about bone changes in these patients. We measured bone mineral density (BMD; Z scores) in PD patients and analyzed its relation to serum biochemical indices and sunlight exposure. We measured BMD in 71 patients in the second metacarpals and divided the patients into two groups according to functional independence; group 1, Hoehn and Yahr stages 1 and 2; and group 2, stages 3 to 5. In four of 20 patients in group 1 (20%), the Z score was less than -1.0, indicating osteopenia. In 51 patients in group 2, 31 (61%) had a Z score less than -1.0. The group 1 patients showed a normal mean serum level of 25 hydroxyvitamin D (25-OHD; 21.7 ng/ml), while most group 2 patients were in a deficiency range (group mean 8.9 ng/ml). Many group 2 patients were sunlight deprived. Both groups had elevated serum ionized calcium levels correlating positively with Hoehn and Yahr stage and markedly depressed serum 1,25 dihydroxyvitamin D (1,25-[OH]2D) concentrations, indicating that immobilization induced hypercalcemia had inhibited 1,25-[OH]2D production. Z scores correlated positively with 25-OHD levels and negatively with parathyroid hormone concentration and Hoehn and Yahr stage. Vitamin D deficiency due to sunlight deprivation and hypercalcemia induces compensatory hyperparathyroidism, which contributes to reduced BMD in PD patients, particularly those who are functionally dependent. Low BMD increases risk of hip fractures in patients with PD but may be improved by vitamin D supplementation. PMID- 9371908 TI - Stereotactic pallidotomy lengthens the transcranial magnetic cortical stimulation silent period in Parkinson's disease. AB - We compared the duration of the EMG cortical stimulation silent period (CSSP) elicited in abductor pollicis brevis using transcranial magnetic stimulation (TMS) before and after stereotactic unilateral globus pallidus internus pallidotomy (PAL) in 12 patients with Parkinson's disease. We used TMS stimulus intensities of 200, 150, 120, and 100% of motor evoked potential (MEP) threshold before and after (86 +/- 25 days) PAL. PAL increased CSSP duration at stimulus intensities of 200% of MEP threshold in the hand contralateral to the stereotactic lesion. In a subset of five patients able to remain at rest during pre-PAL testing sessions, PAL decreased the resting MEP/M-wave area ratio in the hand contralateral to the lesion at a stimulus intensity of 120% of MEP threshold. PAL did not significantly modify the effects of TMS in the hand ipsilateral to the globus pallidus lesion. The results suggest that PAL improves the function of cortical motor inhibitory circuits in Parkinson's disease. PMID- 9371909 TI - Incidence of progressive supranuclear palsy and multiple system atrophy in Olmsted County, Minnesota, 1976 to 1990. AB - Information on the incidence of progressive supranuclear palsy (PSP) is limited; incidence rates for multiple system atrophy (MSA) are not available. We studied the incidence of PSP and MSA in Olmsted County, Minnesota, for the years 1976 to 1990. This study was part of a larger investigation of all forms of parkinsonism. We used the medical records-linkage system of the Rochester Epidemiology Project to identify all subjects whose records contained documentation of any from of parkinsonism, related neurodegenerative diseases, or tremor of any type. A nurse abstractor screened the records and, when applicable, a neurologist reviewed them to determine the presence or absence of parkinsonism. Cases of parkinsonism were classified using specified diagnostic criteria. Population denominators were derived from census data and were corrected by removing prevalent cases of parkinsonism. Over the 15 years of the study, we found 16 incident cases of PSP and nine incident cases of MSA. No cases of PSP or MSA had onset before age 50 years. The average annual incidence rate (new cases per 100,000 person-years) for ages 50 to 99 years was 5.3 for PSP and 3.0 for MSA. The incidence of PSP increased steeply with age from 1.7 at 50 to 59 years to 14.7 at 80 to 99 years, and was consistently higher in men. Median survival time from symptom onset was 5.3 years for PSP and 8.5 years for MSA. The incidence of PSP increases with age and is consistently higher in men at all ages. PSP and MSA are more common than previously recognized. PMID- 9371910 TI - Multifocal motor neuropathy. Serum IgM anti-GM1 ganglioside antibodies in most patients detected using covalent linkage of GM1 to ELISA plates. AB - IgM anti-GM1 antibodies occur with increased frequency in the serum of patients with multifocal motor neuropathy (MMN). We tested the ability of serum IgM from patients with MMN to bind to GM1 ganglioside covalently bound to secondary amino groups on ELISA plates (Co-GM1). The Co-GM1 technique detected high titer (> 1,800), selective, serum IgM binding to GM1 ganglioside in 85% of our MMN patients (23/27), a significantly greater frequency compared with figures of 37% and 52% found using our previous testing methods. Selective IgM anti-GM1 antibodies showed disease specificity. The only other patients with selective, high-titer IgM anti-GM1 antibodies had either chronic motor neuropathy without conduction block or acute immune neuropathy in China. No patient from the amyotrophic lateral sclerosis, chronic inflammatory demyelinating polyneuropathy, Guillain-Barre, or systemic immune disorder control groups had selective IgM anti GM1 antibodies at titers greater than 1,800 detected using Co-GM1 ganglioside as ELISA antigen. Titers of IgM anti-GM1 antibodies in MMN (averaging 31,000 +/- 15,000) were more than fourfold higher with Co-GM1 than with previous anti-GM1 assay methods, using conventional ELISA plates with GM-1 antigen alone (7,200 +/- 4,400) or in a lipid environment (3,600 +/- 1,300). We conclude that using ELISA testing with Co-GM1 antigen, serum anti-GM1 autoantibodies are a useful marker for MMN, because they are present in 85% of MMN patients and, at titers greater than 1,800, have strong specificity for immune-mediated motor neuropathies. PMID- 9371911 TI - Impaired motor cortex inhibition in patients with amyotrophic lateral sclerosis. Evidence from paired transcranial magnetic stimulation. AB - We investigated 14 patients with amyotrophic lateral sclerosis (ALS) by paired conditioning-test transcranial magnetic stimulation to test the hypothesis that the motor cortex is hyperexcitable in ALS. Intracortical (corticocortical) inhibition was significantly less in the ALS group than in an age-matched healthy control group (85.3 +/- 27.0% versus 45.2 +/- 15.5%, respectively; p < 0.0001). In contrast, intracortical facilitation, motor threshold, and cortical silent period duration in the ALS patients were not different from the control group. We suggest that the selective abnormality of intracortical inhibition is best compatible with an impaired function of inhibitory interneuronal circuits in the motor cortex that in turn renders the corticomotoneuron hyperexcitable. PMID- 9371912 TI - Autosomal dominant progressive syndrome of motor-speech loss without dementia. AB - This patient report describes a 68-year-old man with progressive dissolution in motor-speech without concomitant language or cognitive decline, with presumed autosomal dominant inheritance. Motor-speech impairments included marked difficulty in articulating words and in coordinating articulation, phonation, and respiration. Brain imaging results revealed severe focal atrophy of the posterior frontal region extending to the anterior parietal and superior temporal regions bilaterally on structural (MRI) and functional (single photon emission computed tomography) brain imaging studies. The involved neural substrate represented the primary motor cortex, premotor cortex (supplementary motor area), and the postcentral gyrus. Familial history included similar difficulties in his mother, her sister, and his own sister. The isolated involvement of the motor-speech processes alone indicated that this syndrome was distinguishable from progressive aphasia associated with prominent loss of language and from Alzheimer's disease. PMID- 9371913 TI - Diabetics do not have increased Alzheimer-type pathology compared with age matched control subjects. A retrospective postmortem immunocytochemical and histofluorescent study. AB - Diabetics have impaired cognitive performance relative to age-matched control subjects, but the pathologic basis for this impairment is unknown. Because Alzheimer-type lesions, including both senile plaques and neurofibrillary tangles, contain glycated proteins and glycation is known to be increased in diabetes, we hypothesized that cognitive impairment in diabetes may be due in part to increased Alzheimer-type pathology. We measured the amount of Alzheimer type pathology in postmortem brains of diabetic and age-matched control subjects with sensitive and specific histofluorescent and immunocytochemical methods. As expected, there were strong correlations between severity of senile plaques and neurofibrillary degeneration and age and also a strong correlation between severity of senile plaques and neurofibrillary degeneration and age and also a strong correlation between the pathologic measures. On the other hand, there was no significant difference between diabetics and control subjects with respect to severity of Alzheimer-type pathology, on average, or with respect to age. This finding was true for diabetics with and without insulin dependence. The results confirm reports showing that diabetes is not a risk factor for Alzheimer-type pathology and suggest that factors other than Alzheimer's disease are responsible for cognitive impairment in diabetics. PMID- 9371914 TI - Neurophysiologic correlates of implicit face memory in intracranial visual evoked potentials. AB - Visual evoked potentials were recorded in the amygdala, hippocampus, mid- and inferotemporal cortex, orbitofrontal cortex, and lateral frontal cortex of seven epileptic patients while they were engaged in a difficult task requiring the discrimination between repeated and nonrepeated faces. The explicit recognition of previously seen faces was at chance levels, as measured by the accuracy of push-button responses. Nevertheless, all subjects showed clear-cut differential evoked responses to repeated versus nonrepeated faces, indicating implicit encoding of the distinction between the two types of stimuli. Differential responses were more frequent in neocortical recording sites (especially in the mid- and inferotemporal leads) than in limbic recording sites such as the amygdala and hippocampus. The authors conclude that implicit encoding processes are modulated by neocortical visual association areas of the temporal lobes. PMID- 9371915 TI - Anosognosia and confabulation during the Wada test. AB - Feinberg et al. proposed that right-hemisphere-damaged stroke patients with anosognosia for hemiplegia (AHP) confabulate seeing stimuli on the left side but those without AHP admit to having inadequate visual information. This study examines the relationship between AHP and confabulation using selective anesthesia of the cerebral hemispheres. Seventeen patients with intractable epilepsy were tested during intracarotid methohexital infusion. For half of the trials, subjects were stimulated on their paretic hand with a material (sandpaper, metal, or cloth), and for the remaining trials they were not stimulated. The subjects were trained to use a pointing response to indicate if they been stimulated and the type of material they had felt. Admission of uncertainty was defined as pointing to a question mark. Confabulation was defined as any material response to a no-touch trial. During anesthesia of either hemisphere, subjects with and without AHP confabulated responses. The AHP and non AHP groups did not differ in admission of uncertainty. Our results support the postulate that confabulation and AHP are independent disorders, and therefore confabulation cannot fully account for AHP. PMID- 9371917 TI - The common MELAS mutation A3243G in mitochondrial DNA among young patients with an occipital brain infarct. AB - The syndrome of mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS) may present with symptoms that resemble a stroke. The strokelike episodes most commonly involve the posterior part of the cerebrum. We identified retrospectively 38 patients with an occipital stroke between ages 18 to 45 years during a 19-year period in a hospital serving as the only neurologic center for a specific population. The common MELAS mutation at the base pair 3243 (A3243G) of the mitochondrial DNA (mtDNA) was analyzed in blood samples. We found four patients (10%) with a clinical or molecular diagnosis of a mitochondrial disorder. Two of the patients carried the A3243G mutation, suggesting frequencies of 6% among patients younger than 45 years of age and 14% among patients younger than 30 years for this mutation. Furthermore, we identified two patients with a clinically definite mitochondrial disorder, and sequencing of the 22 transfer RNA genes revealed the mtDNA mutation A12308G in one patient. Clinical evaluation revealed that occipital stroke was part of a more complex syndrome in these four patients. These population-based findings demonstrate that the A3243G mutation in the mtDNA, and mitochondrial disorders are not uncommon among young patients with occipital stroke. PMID- 9371916 TI - Hereditary endotheliopathy with retinopathy, nephropathy, and stroke (HERNS). AB - We describe a Chinese American family with a hereditary syndrome consisting of retinopathy, nephropathy, and stroke, affecting 11 members spanning three generations. Ophthalmologic evaluations revealed macular edema with capillary dropout and perifoveal microangiopathic telangiectases. Several members had renal abnormalities with proteinuria and hematuria. Initial manifestations were visual impairment and renal dysfunction; neurologic deficits occurred in the third or fourth decade of life. Symptoms included migraine-like headache, psychiatric disturbance, dysarthria, hemiparesis, and apraxia. Neuroimaging consistently demonstrated contrast-enhancing subcortical lesions with surrounding edema. Ultrastructural studies showed distinctive multilaminated vascular basement membranes in the brain and in other tissues, including the kidney, stomach, appendix, omentum, and skin. Genetic analysis ruled out linkage to the CADASIL locus on chromosome 19. Distinct from CADASIL, hereditary endotheliopathy with retinopathy, nephropathy, and stroke (HERNS) is an autosomal dominant multi infarct syndrome with systemic involvement. PMID- 9371918 TI - Acute stroke: prognosis and a prediction of the effect of medical treatment on outcome and health care utilization. The Copenhagen Stroke Study. AB - Medical treatment of acute stroke with tissue plasminogen activator (tPA) was recently approved in the United States, and neuroprotective agents are being developed. Should all patients with stroke, regardless of severity, receive such treatment? In the Copenhagen Stroke Study we studied the prognosis of stroke in 1,351 unselected patients from a well-defined catchment area treated in a community-based stroke unit from the time of acute admission to death or the end of rehabilitation. Outcome measures were mortality, discharge rates to the patients' own home or to a nursing home, length of hospital stay, and neurological and functional outcomes. Prognosis was stratified according to initial stroke severity measured by the Scandinavian Neurological Stroke Scale (SSS) on admission. We estimated the effect of medical treatment on prognosis and health care utilization by assuming a medically induced decrease in initial stroke severity by 5 and 10 points in the initial SSS score. This mild and moderate decrease in initial stroke severity corresponded to an overall improvement in outcome and an overall cost reduction through shorter hospital stays. This was also true in patients with both mild and moderate stroke. However, in patients with severe stroke, survival increases expenses because of an increased discharge rate to a nursing home and an increase in the cost of acute care and rehabilitation. Future medical stroke trials should therefore focus on the effect and cost of treatment, especially in patients with severe stroke, and search for factors predictive of good clinical outcome in this group. PMID- 9371919 TI - Clinical profiles predictive of outcome in pontine hemorrhage. AB - We reviewed predictive factors of poor outcome in pontine hemorrhage in 38 patients admitted to the neurological-neurosurgical intensive care unit. Twenty one patients died within days of admission (55%). Nine patients were severely or moderately disabled and dependent on others for daily care (24%). Eight patients made a good recovery (21%). Death was significantly more common in patients with a history of hypertension, coma on admission, absent motor response, absent corneal reflex or oculocephalic responses. However, clinical and CT features observed only in patients who died were hyperthermia (core temperature > 39 degrees C), tachycardia (> 110 beat/min), CT evidence of extension into the midbrain and thalamus, and acute hydrocephalus on admission. Good recovery only occurred in patients who were alert on admission and had small unilateral pontine hemorrhages. These clinical profiles should be useful in determining the level of care and future resuscitative efforts. PMID- 9371920 TI - Basilar artery embolism. Clinical syndrome and neuroradiologic patterns in patients without permanent occlusion of the basilar artery. AB - The objective of this study was to clarify the clinical and radiologic features, risk factors, and prognosis of basilar embolism without permanent basilar artery occlusion. Forty-five patients (mean age, 59 years) with basilar artery embolism participated in the study. Patients with basilar artery occlusion were excluded. The Glasgow Coma Scale (GCS) score on admission was < 7 in five patients, 7 to 12 in 11 patients, and > 12 in 29 patients. Etiologic factors were cardiac arrhythmia (17 patients), vertebral artery occlusion (12 patients), cervical spine trauma (4 patients), embolism following angiography (2 patients), and surgery (1 patient). MRI was performed in 17 patients and CT in 39 patients. Radiologic examinations were initially normal in 14 patients and remained normal in three patients. Final infarct localization was the thalamus (36 patients), cerebellum (20 patients), posterior cerebral artery territory (21 patients), midbrain (12 patients), and pons (8 patients). Eight to 12 weeks after stroke 12 patients were without clinical signs (Glasgow Outcome Scale [GOS] 1), 15 patients had minor neurologic deficits (GOS 2), 10 were severely disabled (GOS 3), and eight patients had died (GOS 5). Outcome correlated with GCS on admission (p < 0.0001) and with the number of ischemic lesions (p = 0.0001). The typical syndrome is an acute loss of consciousness followed by multiple brainstem symptoms. Usually, clinical symptoms improve rapidly and, in some patients, completely. Compared with basilar occlusion, basilar embolism has a relatively low mortality and outcome is frequently excellent. PMID- 9371921 TI - I. Impaired dark adaptation in symptomatic carotid artery disease. AB - It has been known for more than a century that even slight hypoxemia reduces dark adaptation. We studied dark adaptation in symptomatic carotid artery disease. Twenty-one consecutive patients scheduled for first-time carotid endarterectomy and 31 age-matched control subjects with normal carotid arteries were examined by dark adaptometry monocularly and were tested repeatedly on consecutive days. The average degree of internal carotid stenosis on the symptomatic side was much greater than that on the contralateral side. Dark adaptation was markedly impaired in the patients as compared with the control subjects. In the patients there was no difference in dark adaptation between the symptomatic and nonsymptomatic sides. The existence of carotid stenosis correlated to the level of dark adaptation. Pupillary size and age correlated to the dark adaptational level but did not affect the effect of carotid stenosis on dark adaptation. The decreased dark adaptation may be due to insufficient blood supply or repeated subclinical microembolization to the retinae, the brain, or both. PMID- 9371922 TI - II. Improved dark adaptation after carotid endarterectomy. Evidence of a long term ischemic penumbra? AB - We have reported that dark vision is impaired in symptomatic carotid artery disease and that the impairment correlates with internal carotid artery stenosis. To find out whether this impairment is reversible after carotid endarterectomy, dark adaptation was examined pre- and postoperatively. Twenty-one consecutive patients were examined by dark adaptometry. Two examinations were done for each eye on two consecutive days pre- and postoperatively. Thirty-one matched control subjects were examined under identical conditions. The control subjects did not have clinical evidence of carotid artery disease. Patients and control subjects were free of ophthalmologic disorders. Dark vision frequently improved remarkably after endarterectomy. The average retinal sensitivity to light in darkness on the operated side doubled, and there was also improvement on the nonoperated side. There was no significant change in dark vision in the control subjects, negating a learning effect. The findings suggest the existence of reversible neuronal ischemia secondary to hemodynamic causes or frequent subclinical microembolization. Because the circulatory conditions are optimized, formerly inactive, surviving neurons may regain function. PMID- 9371923 TI - Motor deficits and optokinetic stimulation in patients with left hemineglect. AB - Optokinetic stimulation with left direction of the movement of luminous dots temporarily improved motor weakness of the left hand in two right-brain-damaged patients with left spatial hemineglect. Stimulation to the right had no effect. In two left-brain-damaged patients, optokinetic stimulation did not affect the right motor weakness, regardless of direction of the movement of the optokinetic stimuli. We suggest that in patients with left hemineglect, contralesional motor deficits have a neglect-related component, which, as other aspects of the neglect syndrome, may be improved by optokinetic stimulation. The mechanisms may include a temporary restoration of the spatial coordinates of bodily representations, pathologically distorted towards the side of the lesion. PMID- 9371924 TI - Sensorimotor cerebral activation during optokinetic nystagmus. A functional MRI study. AB - Self-motion or object motion can elicit optokinetic nystagmus (OKN), which is an integral part of dynamic spatial orientation. We used functional MR imaging during horizontal OKN to study cerebral activation patterns in sensory and ocular motor areas in 10 subjects. We found activation bilaterally in the primary visual cortex, the motion-sensitive areas in the occipitotemporal cortex (the middle temporal and medial superior temporal areas), and in areas known to control several types of saccades such as the precentral and posterior median frontal gyrus, the posterior parietal cortex, and the medial part of the superior frontal gyrus (frontal, parietal, and supplementary eye fields). Additionally, we observed cortical activation in the anterior and posterior parts of the insula and in the prefrontal cortex. Bilateral activation of subcortical structures such as the putamen, globus pallidus, caudate nucleus, and the thalamus traced the efferent pathways of OKN down to the brainstem. Functional MRI during OKN revealed a complex cerebral network of sensorimotor cortical and subcortical activation. PMID- 9371925 TI - Clinical-pathologic correlation in a patient with selective loss of hair cells in the vestibular endorgans. AB - We found a selective loss of vestibular hair cells in a patient followed for more than 10 years with imbalance and oscillopsia due to idiopathic progressive loss of vestibular function. Hearing function and cochlear hair cells were normal. The vestibulo-ocular reflex (VOR) gain at high frequencies was relatively maintained despite marked shortening of the dominant VOR time constant (to less than 500 ms). Ultrastructural examination of remaining hair cells showed mitochondrial abnormalities. The ultrashort VOR time constant probably resulted from changes in firing patterns of the primary afferent nerves due to loss of hair cells and impaired energy metabolism in remaining hair cells. PMID- 9371926 TI - Congenital porencephaly and hippocampal sclerosis. Clinical features and epileptic spectrum. AB - We studied clinical features and seizure localization in 14 patients with porencephaly and intractable seizures. Perinatal complications were present in nine patients, childhood febrile convulsions in two, congenital hemiparesis in 12, and intellectual impairment in seven. Ten patients had psychoparetic complex partial seizures (CPS), three had sensorimotor simple partial seizures, and one had generalized tonic-clonic seizures. Surface EEG showed temporal onset in nine patients (one bitemporal) and extratemporal onset in four. MRI showed porencephaly in the distribution of the middle cerebral artery in eight patients, posterior cerebral in three, internal carotid in one, and multiple vessels in two. MR-based volumetry revealed hippocampal formation atrophy in 13 patients (eight unilateral and five bilateral) and amygdalar atrophy in 10 patients (nine unilateral and one bilateral). Hippocampal formation atrophy was concordant with CPS semiology in 10 patients (71%) and with EEG temporal localization in nine patients. Two patients had pathologic confirmation of mesial temporal sclerosis and were seizure free after temporal lobectomy. We conclude that mesial temporal sclerosis often coexists with porencephaly and is the likely seizure focus in the presence of concordant electroclinical data. This recognition implies that effective surgical intervention can be offered to certain patients with porencephaly-related seizure disorders. The dual pathology and association with perinatal cerebral vascular occlusion suggest a common ischemic pathogenesis. PMID- 9371927 TI - Electroconvulsive therapy for treatment of intractable seizures. Initial findings in two children. AB - We treated two children with intractable epilepsy with electroconvulsive therapy (ECT) for seizure control. One child showed a change in seizure pattern with treatment, which at greater intensity was also effective in stopping nonconvulsive status epilepticus. The other child showed a decrease in spontaneous seizure frequency during short-term treatment. These findings suggest a possible role for ECT in the management of intractable epilepsy in children who are not candidates for epileptic surgery. PMID- 9371928 TI - Adult-onset Krabbe disease with homozygous T1853C mutation in the galactocerebrosidase gene. Unusual MRI findings of corticospinal tract demyelination. AB - A 51-year-old woman developed a slowly progressive spastic paraparesis and diminished vibration sense beginning at age 38. Intellectual capacity was normal. Krabbe disease was confirmed by markedly reduced leukocyte galactocerebrosidase (GALC) activity, typical inclusions in Schwann cell cytoplasm, and an identification of the homozygous point mutation T1835C (Leu618Ser) in the GALC gene. T2-weighted MRI of the brain showed symmetric high-signal-intensity lesions in the bilateral frontoparietal white matter, the centrum semiovale, and the posterior limb of the internal capsule with sparing of the periventricular white matter. This case is unusual because of the late onset, protracted clinical course, and MRI findings of demyelination confined to the corticospinal tracts. PMID- 9371929 TI - Delayed posthypoxic demyelination. Association with arylsulfatase A deficiency and lactic acidosis on proton MR spectroscopy. AB - Delayed demyelination is a rare and poorly understood complication of hypoxic brain injury. A previous case report has suggested an association with mild-to moderate deficiency of arylsulfatase A. We describe a 36-year-old man who recovered completely from an episode of hypoxia related to drug overdose, and 2 weeks later progressed from a confusional state to deep coma. MRI showed diffuse white matter signal changes, and brain biopsy demonstrated a noninflammatory demyelinating process. Proton magnetic resonance spectroscopy revealed elevated choline and lactate and reduced N-acetyl aspartate signal in the affected white matter, consistent with demyelination and a shift to anaerobic metabolism. Arylsulfatase A activity from peripheral leukocytes was approximately 50% of normal, consistent with a "pseudodeficiency" phenotype. These findings confirm the hypothesis that relative arylsulfatase A deficiency predisposes susceptible individuals to delayed posthypoxic leukoencephalopathy and implicates lactic acidosis in the pathogenesis of this disorder. PMID- 9371930 TI - The 5-year risk of MS after optic neuritis. Experience of the optic neuritis treatment trial. AB - The objective of our study was to assess the 5-year risk of and prognostic factors for the development of clinically definite multiple sclerosis (CDMS) following optic neuritis. In a prospective cohort study design, 388 patients, who did not have probable or definite MS at study entry enrolled in the Optic Neuritis Treatment Trial between 1988 and 1991, and were followed for the development of CDMS. The 5-year cumulative probability of CDMS was 30% and did not differ by treatment group. Neurologic impairment in the patients who developed CDMS was generally mild. Brain MRI performed at study entry was a strong predictor of CDMS, with the 5-year risk of CDMS ranging from 16% in the 202 patients with no MRI lesions to 51% in the 89 patients with three or more MRI lesions. Independent of brain MRI, the presence of prior nonspecific neurologic symptoms was also predictive of the development of CDMS. Lack of pain, the presence of optic disk swelling, and mild visual acuity loss were features of the optic neuritis associated with a low risk of CDMS among the 189 patients who had no brain MRI lesions and no history of neurologic symptoms or optic neuritis in the fellow eye. The 5-year risk of CDMS following optic neuritis is highly dependent on the number of lesions present on brain MRI. However, even a normal brain MRI does not preclude the development of CDMS. In these patients with no brain MRI lesions, certain clinical features identify a subgroup with a particularly low 5-year risk of CDMS. PMID- 9371931 TI - Risk factors for developing multiple sclerosis after childhood optic neuritis. AB - We reviewed the records of all children (younger than 16 years of age) who presented with a diagnosis of optic neuritis (ON) identified through the comprehensive records-linkage system at the Mayo Clinic and identified 94 cases between 1950 and 1988 with a documented history of idiopathic ON. Detailed follow up information was available on 79 patients, with a median length of follow-up of 19.4 years. Life-table analysis showed that 13% of the 79 patients with isolated ON had progressed to clinically or laboratory-supported definite multiple sclerosis (MS) by 10 years of follow-up, 19% by 20 years, 22% by 30 years, and 26% by 40 years. Gender, age, funduscopic findings, visual acuity, or family history of either ON or MS did not predict the development of MS. The presence of bilateral sequential or recurrent ON increased the risk of developing MS (p = 0.002; hazard ratio = 5.09), whereas the presence of infection within 2 weeks before the onset of ON decreased the risk of developing MS (p = 0.060; hazard ratio = 0.24). This study of childhood ON supports the lower risk of recurrence and progression to MS compared with adults. PMID- 9371932 TI - The measurement of ambulatory impairment in multiple sclerosis. AB - The objective of this study was to examine the relationships between continuous measures of ambulatory impairment in MS patients and their ordinal counterparts. Much of the disability caused by MS is due to ambulatory impairment. The Expanded Disability Severity Scale (EDSS) and the Ambulation Index (AI) are ordinal measures of MS severity based largely on the maximal distance subjects can walk (Dmax) and the time to walk 8 m (T8), respectively. At EDSS levels 6.0 to 7.0 and AI levels 3 to 6, scores are defined more by the use of ambulatory aids, rather than by Dmax or T8. We determined Dmax (up to 500 m), T8, the EDSS score, and the AI in 237 ambulatory MS patients. The maximal distance subjects could walk and T8 were strongly related to their ordinal counterparts (Spearman r = 0.65 and 0.91, respectively), but the continuous measures showed considerable variability within EDSS and AI levels that the ordinal scales did not reflect. Most of the variability occurred at EDSS levels 6.0 to 7.0 and AI levels 3 to 6. Because the use of an aid did not clearly predict Dmax or T8, many patients in these ranges had better ambulatory function based on the continuous measures than those with less disability according to the ordinal scales. We found that Dmax and T8 provide more precise information about ambulatory impairment in MS than do the EDSS and AI, allowing better discrimination of differences between patients and potentially greater sensitivity to detect therapeutic effects in clinical trials. PMID- 9371933 TI - Chemosensory event-related potentials in response to trigeminal and olfactory stimulation in idiopathic Parkinson's disease. AB - Decrease of olfactory function in patients with Parkinson's disease (PD) has been reported by several authors. The current study investigated olfaction in PD patients using olfactory event-related potentials (OERPs) as an electrophysiologic correlate of olfactory function in combination with psychophysical testing. A specific focus was the influence of antiparkinsonian drugs. We investigated PD patients treated with antiparkinsonian drugs (n = 13) and PD patients who received no pharmacologic treatment (n = 18). They were compared to age- and sex-matched control subjects (n = 38). To obtain OERPs, stimulants were chosen to stimulate specifically the olfactory nerve (2.1 ppm vanillin, 0.8 ppm H2S). In addition, chemosomatosensory event-related potentials were recorded after trigeminal stimulation with 52% v/v CO2. Moreover, the subjects' ability to identify and to discriminate odorants was tested by means of a "squeeze bottle" technique. The study yielded the following major results: (1) Odor identification was impaired in PD patients. It was not influenced by treatment with antiparkinsonian drugs. (2) The OERP latencies were prolonged in both PD patients taking and not taking antiparkinsonian drugs; however, this effect was more pronounced in PD patients taking antiparkinsonian drugs. (3) The intranasal chemosensory trigeminal system seemingly was neither affected by the neuronal degeneration seen in PD nor by treatment with antiparkinsonian drugs. PMID- 9371934 TI - MPTP induces dystonia and parkinsonism. Clues to the pathophysiology of dystonia. AB - The pathophysiology of dystonia is unclear, but several clues implicate striatal dopamine dysfunction. In contrast, the causal relationship between striatal dopamine deficiency and parkinsonism is well defined. We now suggest that parkinsonism or dystonia may occur following striatal dopamine deficiency. Baboons treated with intracarotid 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) developed transient hemidystonia prior to hemiparkinsonism. The day after MPTP treatment, most animals had spontaneous ipsilateral turning. Within a few days, all developed contralateral hemidystonia, with the arm and leg extended and externally rotated. This transient dystonia preceded hemiparkinsonism with flexed posture, bradykinesia, and postural tremor that persisted for up to 1.5 years. Dystonia corresponded temporally with a decreased striatal dopamine content and a transient decrease in D2-like receptor number. The time course of dystonia and parkinsonism is analogous to lower limb dystonia as the first, frequently transient, symptom of Parkinson's disease in humans. The association of striatal dopamine deficiency with dystonia and parkinsonism implies that other factors influence clinical manifestations. PMID- 9371935 TI - Symptomatic orthostatic tremor in pontine lesions. AB - Orthostatic tremor (OT) is a rare movement disorder that consists of involuntary shaking of the legs and trunk present only on standing. Although the origin and the mechanism of this condition are not well understood, the neurophysiologic abnormalities and PET studies suggest a central origin. We describe the clinical and radiologic features of two patients with symptomatic OT and associated pontine lesions, and conclude that OT may arise from dysfunction of the cerebellum or related pontine structures. PMID- 9371936 TI - Gabapentin for familial paroxysmal dystonic choreoathetosis. AB - We present a 4-year-old girl with stereotyped episodes of inability to speak and dystonic posturing of the face and extremities lasting 20 minutes. An older brother and mother had similar spells in childhood. Routine and video-EEG during events were normal. The diagnosis was non-kinesigenic paroxysmal dystonic choreoathetosis since the episodes were not exacerbated by movement. Gabapentin 10 mg/kg/d eliminated most attacks. PMID- 9371938 TI - Biotin catabolism is accelerated in adults receiving long-term therapy with anticonvulsants. AB - Using serum biotin concentration as the indicator, a previous study reported biotin deficiency resulting from long-term anticonvulsant therapy. However, serum biotin may not be a good indicator of tissue biotin status. Using better indicators of biotin status in anticonvulsant-treated subjects, we found increased urinary excretion of biotin catabolites and 3-hydroxyisovaleric acid, an organic acid produced in greater quantities secondary to reduced activity of a biotin-dependent carboxylase. We conclude that anticonvulsant treatment led to increased biotin catabolism and probably to reduced biotin status. PMID- 9371937 TI - Multiorgan dysfunction and disseminated intravascular coagulation in children receiving lamotrigine and valproic acid. AB - Two children developed multiorgan dysfunction with disseminated intravascular coagulation 9 days after lamotrigine was added to their antiepileptic therapy, which included valproic acid. During the episodes, rhabdomyolysis was detected in one of them, while being seizure-free, suggesting that this adverse reaction may involve muscular tissue. PMID- 9371939 TI - Cerebral involvement in celiac disease: a serial MRI study in a patient with brainstem and cerebellar symptoms. AB - A patient with celiac disease and relapsing-progressive symptoms suggesting brainstem and cerebellar involvement underwent serial MRIs. The first examination revealed multiple enhancing and nonenhancing lesions. Thereafter, a large enhancing cerebellar lesion appeared, followed by severe cerebellar atrophy. The presence of structural neuronal damage was confirmed by proton MR spectroscopy and magnetization transfer imaging. MRI results and CSF findings suggested that neurologic complications were more likely due to an inflammatory process. PMID- 9371940 TI - Multifocal brain MRI artifacts secondary to embolic metal fragments. AB - We report a patient with unusual MRI abnormalities that had the physical characteristics of ferromagnetic artifact. We believe that the MRI artifacts were due to microscopic embolic metal fragments, most likely from a mechanical heart valve prosthesis. Potential sources of metal emboli should be considered in patients with MRI abnormalities compatible with ferromagnetic artifact. PMID- 9371941 TI - Paraneoplastic myasthenia gravis: detection of anti-MGT30 (titin) antibodies predicts thymic epithelial tumor. AB - It has been suggested that antibodies against non-acetylcholine receptor proteins of striated muscle are markers of the presence of a thymic epithelial tumor in patients with myasthenia gravis (MG). These antibodies may be measured using an immunofluorescence assay against striated muscle (anti-STR) or an ELISA with a recombinant 30-kd titin fragment (anti-MGT30). To directly compare anti-STR with anti-MGT30, we examined the sera of 276 consecutive patients with known or suspected MG. Definite diagnoses and thymic histology, if available, were correlated with the antibody assays. Of the 276 patients, 164 had MG. Thymic histology was obtained in 44 patients: 18 had lymphofollicular hyperplasia, 13 thymic epithelial tumors, 8 atrophy, and 5 were normal. When compared with anti STR, anti-MGT30 showed a sensitivity of 69% (STR 77%), specificity of 100% (STR 56%, p = 0.026), negative predictive value of 82% (STR 77%), and positive predictive value of 100% (STR 56%, p = 0.003) for the identification of a thymic epithelial tumor versus thymic hyperplasia. We conclude that the anti-MGT30 ELISA is better than the anti-STR immunofluorescence assay for the diagnosis of paraneoplastic MG. PMID- 9371942 TI - Congenital myotonic dystrophy pathology and somatic mosaicism. AB - We present the pathology and molecular genetic analysis of an infant with congenital myotonic dystrophy. The proband/infant, born at 35 weeks' gestational age to a mother with myotonic dystrophy and 750 CTG repeats, was markedly hypotonic and had severe cardiomyopathy. She died after 16 days of life. At autopsy, skeletal and heart muscles were immature and had a decrease in contractile elements. DNA CTG trinucleotide repeat analysis of the proband demonstrated 2,480 repeats in blood and a slightly greater number of repeats in skeletal muscles, viscera, and gray matter. Corresponding to the clinical course and pathology, cardiac tissues displayed somatic mosaicism, with repeats ranging from 2,760 to 3,220. PMID- 9371943 TI - Spinocerebellar ataxia type 1 and familial spontaneous pneumothorax. AB - We report two siblings with spinocerebellar ataxia type 1 (SCA1) who experienced frequent episodes of spontaneous pneumothorax. Radiologic findings indicated underlying degenerative changes in the lungs. This suggests a possible pathophysiologic relationship between SCA1 and familial occurrence of spontaneous pneumothorax. PMID- 9371944 TI - Giant cell arteritis with unusual flow-related neuro-ophthalmologic manifestations. AB - We report two patients with giant cell arteritis and unusual neuro-ophthalmic findings. One patient developed a horizontal one and a half syndrome associated with upright posture. The responsible lesion was dorsal pontine infarction. The other patient had bright light-induced amaurosis fugax in the absence of extracranial carotid occlusive disease. Both patients continued to have symptoms despite the use of high-dose intravenous corticosteroids. The manifestations of both patients occurred early in the course of giant cell arteritis and were flow related. PMID- 9371945 TI - Cocaine and pupillary-sparing oculomotor nerve paresis. PMID- 9371947 TI - Status epilepticus amauroticus. PMID- 9371946 TI - Vigabatrin aggravates absences and absence status. PMID- 9371948 TI - A case of Creutzfeldt-Jakob disease with a point mutation at codon 232: correlation of MRI and neurologic findings. PMID- 9371949 TI - Gadolinium-enhancement of the spinal posterior roots in acute sensory ataxic neuropathy. PMID- 9371951 TI - Nonmotor fluctuations in patients with Parkinson's disease. PMID- 9371950 TI - Nonmotor fluctuations in patients with Parkinson's disease. PMID- 9371952 TI - Cytomegalovirus infection and Guillain-Barre syndrome. PMID- 9371953 TI - Crack cocaine use and stroke in young patients. PMID- 9371954 TI - Pain in Guillain-Barre syndrome. PMID- 9371956 TI - Recurrent optic neuromyelitis with endocrinopathies. PMID- 9371955 TI - Influenza immunization in multiple sclerosis. PMID- 9371957 TI - Craniectomy: an aggressive treatment approach in severe encephalitis. PMID- 9371958 TI - Multiple brain gas embolism after injection of concentrated hydrogen peroxide. PMID- 9371959 TI - PMP22 frameshift mutation and hereditary neuropathy with liability to pressure palsies. PMID- 9371960 TI - Acephalgic migraine or childhood occipital seizures? PMID- 9371961 TI - Phobic postural vertigo. PMID- 9371962 TI - Neurology workforce and the Residency Review Committee. PMID- 9371964 TI - Neuroselective current perception threshold quantitative sensory test: a re evaluation. PMID- 9371963 TI - Neurology workforce and the Residency Review Committee. PMID- 9371965 TI - The lost opportunity of the Health Research Fund. Commentary. PMID- 9371966 TI - Transcriptional regulation in myeloid cell differentiation. AB - Myeloid cell differentiation has been investigated on many levels, from the cytokine signals required by each cell lineage to the scheduled expression of distinctive myeloid cell-specific genes and the programmed appearance of characteristic cell surface markers. By analogy to progress in other developmental systems, such as muscle and liver cell differentiation, it should be possible to establish a hierarchy of differentiation signals and transcriptional processes for developing myeloid cells. Current research centers on the cooperation between tissue-specific and more widely expressed transcription factors in the stage-specific regulation of genes essential to myelopoiesis. An attractive emerging concept implicates the programmed regulation of key transcription factors at different stages of development, coordinated by receptor-mediated signals from myeloid colony-stimulating factors. In addition, molecular studies of genes adjacent to the breakpoints of chromosomal translocations in the myeloid leukemias have begun to clarify how aberrantly activated transcription factors can disrupt normal developmental programs and contribute to malignant transformation. PMID- 9371967 TI - Mechanisms of cell commitment in myeloid cell differentiation. AB - The hematopoietic developmental hierarchy originates with a rare population of lymphohematopoietic stem cells that are capable of extensive self-renewal as well as the continuous generation of more developmentally restricted progeny. The generation of mature blood cells from these pluripotent hematopoietic stem cells involves the highly regulated progression through successive stages involving commitment to a specific cell lineage, terminal differentiation of lineage restricted progenitors, and growth arrest. Although the differentiation commitment of stem cells may be intrinsically determined, it is apparent that a wide variety of external and internal stimuli can influence and modulate lineage choice and differentiation. These factors cooperate with cellular transcription factors to activate or repress the expression of genes responsible for lineage choice, diverse mature phenotypes, and cell cycle progression. The extrinsic and genetic mechanisms that orchestrate the differentiation commitment and myeloid lineage restriction of pluripotent stem cells are of fundamental importance in the regulation of hematopoiesis. The elucidation of these mechanisms of normal myeloid differentiation has provided instrumental insights into the biology of leukemia and other hematopoietic disorders. PMID- 9371968 TI - Structure and function of the cytokine receptor superfamily. AB - The cytokine receptor superfamily is a group of transmembrane proteins, characterized by a common extracellular structure--two barrels composed of seven beta strands each. Over the past year, several new members of the cytokine receptor family have been described, and new insights have been made into how related receptors share common subunits. Also this year, the ligand for the orphan cytokine receptor c-Mpl was identified and shown to stimulate megakaryocyte development and thrombopoiesis. Progress has been made in unraveling the precise atomic basis for ligand-receptor interactions and the role that subunit association plays in receptor activation. Finally, advances have been made in understanding the organization of the intracellular domain and how signaling to the nucleus is achieved. Together, these new results have led to a greater appreciation of the role that cytokine receptors play in the regulation of proliferation and lineage-specific differentiation during hematopoiesis. PMID- 9371969 TI - Signal transduction during myeloid cell differentiation. AB - The intracellular signaling mechanisms that dictate myeloid differentiation and proliferation are discussed. Independent hematopoietic signaling pathways including p21ras pathway, c-myc pathway, and Jak-STAT pathway are defined. Emphasis is given to the process of information integration at the nucleus, by which developmental programs may be converted from binary decisions into the complex response patterns explaining hematopoietic diversity. Coupling between signaling and transcription is emphasized. PMID- 9371971 TI - The interaction of leukocytes with platelets in blood coagulation. AB - The concept that leukocytes play an active role in hemostasis and thrombosis has only recently been accepted. Leukocytes may influence coagulation directly, by the production of procoagulant and anticoagulant molecules, or indirectly, by actions on vascular cells including platelets, endothelial cells, and other leukocytes. This review examines the role of leukocytes in coagulation with an emphasis on regulation of leukocyte function by interactions, with platelets. Activated platelets may serve both to localize leukocytes in areas of thrombosis and to modulate their function. Over the past year, several in vitro studies further defined molecular mechanisms by which leukocytes may regulate coagulation. Further, in vivo studies have provided support for the relevance of these mechanisms in pathophysiologic coagulation. PMID- 9371970 TI - Leukocyte interaction with protein cascades in blood coagulation. AB - Coagulation preserves the homeostasis of internal body fluids against life threatening blood losses. Although generally viewed as a regulated enzymatic cascade, this mechanism depends on the participation of vascular cells. Leukocytes, in particular, have evolved a formidable machinery to initiate and amplify blood clotting reactions through the recognition of cell surface receptors, proteolytic enzymes, and cofactor and regulatory molecules. The consequences of thrombin generation on the leukocyte surface are not exclusively restricted to the hemostatic balance. Rather, thrombin and other coagulation proteases influence a panoply of cellular functions, ranging from activation pathways and adherence phenomena, to DNA synthesis and cell proliferation of normal and malignant phenotypes. For this multivalency of cellular responses, the process of blood coagulation is now perceived as a broad cell signaling mechanism that participates in all pathophysiological aspects of host inflammatory responses. PMID- 9371972 TI - The respiratory burst oxidase. AB - The respiratory burst oxidase catalyzes the production of O2- by activated phagocytes and B lymphocytes. Activation is accomplished by any number of signal transduction pathways, and involves protein kinase C, MAP kinase, or both, and perhaps lipid-mediated pathways. Failure of O2- production is characteristic of chronic granulomatous disease, an inherited disorder of phagocyte function. A number of new mutations responsible for chronic granulomatous disease have been reported. O2- production is also altered in other diseases, most notably certain hematologic malignancies. PMID- 9371973 TI - The leukocyte beta 1 integrins. AB - We summarize publications appearing in the past year on the blood cell beta 1 integrins VLA-1 through -6, including characterization of their ligand interactions, activation epitopes, signaling mechanisms, cellular distribution, and in vivo relevance. These studies extend our understanding of the beta 1 integrins, and continue to underscore their importance in leukocyte biology, which derives from their central role in mechanisms of cellular adhesion, growth, and differentiation. PMID- 9371974 TI - The L-selectin adhesion system. AB - L-selectin is a cell surface glycoprotein expressed on most leukocyte subsets that mediates leukocyte interaction with ligands on lymphoid tissue high endothelial venule cells as well as with ligands on activated endothelium at sites of inflammation in nonlymphoid organs. Similar to two other members of the selectin family, L-selectin behaves as a lectin, recognizing carbohydrate ligands in a calcium-dependent fashion. Recent in vivo studies reveal the importance of L selectin expression in both normal and pathologic conditions. PMID- 9371975 TI - Signaling mechanisms in human neutrophils. AB - Leukocytes possess many properties critical to their effective functioning in inflammation, including the ability to migrate to the site of inflammation and release an impressive armamentarium of toxic products such as proteolytic enzymes, reactive oxygen species, and cationic proteins, capable of killing invading pathogens. This review focuses on the transmembrane signaling events whereby factors present in an inflammatory milieu activate these leukocyte effector functions. In the past several years, many of the components of these pathways have been elucidated at the molecular level, but large gaps remain in our understanding. The discussion follows the path beginning from the exofacial side of the plasma membrane toward the cell interior: from membrane receptors, GTP-binding proteins and adapter proteins to intermediary pathways including phospholipases and protein kinases. A detailed understanding of these regulatory mechanisms will have important therapeutic implications for amelioration of inflammatory tissue injury. PMID- 9371976 TI - Ion transport and the function of phagocytic cells. AB - Inorganic ions constitute the predominant osmolytes of blood cells and are therefore the main determinant of the cellular volume. In leukocytes, maintenance of constant cell size is accomplished by modulating the ionic permeability of the membrane. In addition, the plasmalemmal ionic permeability dictates the transmembrane potential, which influences a variety of cellular responses. Inorganic ions are also essential for the regulation of the intracellular pH and play an active role in signal transduction during phagocyte activation. This chapter reviews recent progress in the area of ion transport in phagocytic leukocytes, with special reference to the physiologic implications to the activation process. PMID- 9371978 TI - Leukocytes. PMID- 9371977 TI - Antineutrophil cytoplasm autoantibodies and vasculitis. AB - Antineutrophil cytoplasm autoantibodies are useful diagnostic serologic markers for a variety of well-known primary vasculitic syndromes, including Wegener's granulomatosis, microscopic polyangiitis, and idiopathic necrotizing and crescentic glomerulo-nephritis. More recently antineutrophil cytoplasm autoantibodies have been found in other vasculitic syndromes, such as Churg Strauss syndrome, Henoch-Schonlein purpura, and some nonvasculitic diseases such as rheumatoid arthritis, inflammatory bowel disease, and autoimmune hepatobiliary diseases. There is now evidence to suggest that infection might be an important etiologic factor in the development of antineutrophil cytoplasm autoantibody associated vasculitides. This link has been strengthened by in vitro data that suggest that antineutrophil cytoplasm autoantibodies are directly involved in the pathogenesis of antineutrophil cytoplasm autoantibody-associated vasculitides. PMID- 9371979 TI - Natural history and determinants of clinical severity of sickle cell disease. AB - Some of the factors determining the extremely variable clinical course of homozygous sickle cell disease are being identified. Genetic factors include alpha-thalassemia, beta-globin gene haplotypes, heterocellular hereditary persistence of fetal hemoglobin, and high total hemoglobin. Other factors include a variety of environmental variables and socioeconomic status. These risk factors, when occurring in conjunction with apparently random precipitating events, produce features of the disease. Many complications--which are age specific, with highest morbidity and mortality in the first 5 years--may be prevented by specific education and prophylaxis. Current median survival in individuals with sickle cell disease in the United States is approximately 40 to 50 years, at which age the major determinants of mortality are chronic end organ damage of the lungs and kidneys. PMID- 9371980 TI - Butyrate in the treatment of sickle cell disease and beta-thalassemia. AB - The search for, and discovery of, a physiologic model in which the developmentally regulated switch from fetal to adult globin gene expression could be prevented has resulted in the development of a new class of therapeutic agents, consisting of simple fatty acids, such as butyric acid, for the treatment of the beta-hemoglobinopathies. Butyrate and related drugs stimulate fetal (gamma ) globin gene expression in erythroid cells cultured from patients, and in chicken, ovine, and primate animal models. The butyrates are perhaps the first class of drugs designed to transcriptionally activate specific genes--in this particular case, to reactivate the developmentally silenced fetal globin genes. Phase I-II clinical trials resulting from this basic research have been initiated on a small scale during the past 3 years. Analysis of two butyrate-derived therapeutic agents, one delivered intravenously and one orally, has shown initial efficacy in stimulating fetal hemoglobin expression in 50% to 85% of patients. Correction of the anemia from the beta-hemoglobinopathy has followed induction of fetal globin, and has been adequate to eliminate the need for erythrocyte transfusions in some patients with beta-thalassemia. These compounds have been relatively safe and without generalized cytotoxicity in patients, but drug tolerance develops in some patients after prolonged therapy. Third-generation, small two- to five-carbon butyrate derivatives are in development. The molecular basis for butyrate action is being defined. Binding of putative regulatory proteins to a specific region of the gamma-globin promoter is altered in vivo in patients receiving butyrate therapy. Further analysis of the mode of action may contribute to development of other therapeutic agents designed to regulate gene transcription. PMID- 9371981 TI - Clinical use of erythropoietin. AB - Recombinant human erythropoietin has been available for clinical use since 1985. It was an immediate success in treating the anemia of chronic renal failure and has also enjoyed some objective success in the treatment of other anemias in either a therapeutic or prophylactic setting, but the issues of appropriate patient selection and cost-benefit ratios are still unresolved. This review discusses the most recent literature concerning the use of recombinant human erythropoietin for the anemia associated with cancer, HIV infection, myelodysplasia, prematurity, autologous blood transfusion, bone marrow transplantation, and chronic renal failure. PMID- 9371982 TI - Regulation of erythropoietin gene expression. AB - The study of erythropoietin gene expression provides a paradigm for understanding gene regulation in response to hypoxia. The sensor for detecting alterations in oxygen tension appears to be a heme protein. Ongoing transcription and protein synthesis are necessary for hypoxic induction of erythropoietin messenger RNA. In the past few years, considerable progress has been made in the identification and characterization of cis-acting elements and trans-acting factors that contribute to erythropoietin gene expression. The erythropoietin promoter and 3' enhancer function synergistically in response to hypoxia. Whereas hypoxia-inducible factor 1 specifically binds to the 3' enhancer conferring hypoxic induction, hepatic nuclear factor 4 interacts with the promoter as well as the 3' enhancer for stimulus- and tissue-specific induction of the erythropoietin gene. In addition, a segment in the 3' untranslated region contributes to the relatively rapid turnover of erythropoietin messenger RNA. PMID- 9371983 TI - Erythrocyte dehydration in pathophysiology and treatment of sickle cell disease. AB - A prominent feature of sickle cell disease is the presence of cells with markedly increased sickle cell hemoglobin concentration, as a consequence of the loss of potassium, chloride, and water from the erythrocyte. Because of the extreme dependency of the kinetic of polymerization on sickle cell hemoglobin concentration, these dehydrated erythrocytes have an increased tendency to polymerize and sickle. Thus blockade of the loss of potassium from the erythrocyte should prevent the increase in sickle cell hemoglobin concentration and reduce sickling. The availability of this potential therapeutic option is based on a detailed knowledge of the mechanisms leading to cell dehydration. Two ion transport pathways, the K-Cl cotransport and the Ca(2+)-activated K+ channel, play a prominent role in the dehydration of sickle erythrocytes. Possible therapeutic strategies include inhibition of K-Cl cotransport by increasing erythrocyte Mg2+ content and inhibition of the Ca(2+)-activated K channel by oral administration of clotrimazole. PMID- 9371984 TI - Advances in the molecular biology of erythrocyte antigens. AB - The past year has seen further advances in our understanding of the molecular biology of the most abundant erythrocyte proteins associated with blood group antigens (band 3, the glycophorins, and the Rh antigen-related proteins). There have also been several important developments in the structural and functional identification of some of the less abundant antigens. These developments include the association of the Colton antigens with the erythrocyte water channel, aquaporin; the cloning of the Duffy antigen and its identification as a chemokine receptor; the cloning of the Kx antigen, which is associated with McLeod syndrome; and the cloning of the LW, CD47, and Xga antigens. PMID- 9371985 TI - Primary polycythemias. AB - In this review, primary polycythemic states are discussed in the context of other polycythemic disorders. Primary polycythemias result from an acquired or inborn mutation affecting hematopoietic and erythroid cells. The best-known type of primary polycythemia is polycythemia vera, which is caused by an acquired somatic mutation of a hematopoietic stem cell with exaggerated myeloid proliferation; the molecular events leading to this disease are not understood. In contrast, primary familial and congenital polycythemias result from inborn mutation affecting hematopoietic and erythroid cells. The molecular mechanisms causing primary familial and congenital polycythemias may be different in different families; some have already been defined. Progress in defining the molecular defect of primary polycythemias and the better understanding of altered signal transduction leading to excessive erythrocyte production should provide important insights into the pathogenesis of primary polycythemias, other leukemic disorders, as well as normal hematopoiesis. Such information should contribute to better understanding of and more effective therapeutic interventions in myeloproliferative and leukemic disorders. PMID- 9371986 TI - Iron chelation therapy. AB - Iron chelation therapy is essential to prevent death from cardiac toxicity in patients with thalassemia major or other severe refractory anemias who need regular blood transfusions. Iron chelating drugs also have potential for clinical use as antiproliferative agents in neoplastic diseases and to reduce free radical induced tissue damage in rheumatoid arthritis, anthracycline-induced cardiotoxicity, and reperfusion injury. Experimental data and clinical trials also suggest they may have therapeutic value as adjuncts to antimalarial and anti Pneumocystis carinii therapy and to reduce aluminum toxicity. There is therefore an urgent need for an orally active, inexpensive iron chelating drug, because desferrioxamine, the only currently widely available iron chelator, must be given parenterally and is expensive, making it unavailable for long-term use in many parts of the world. L1 (also known as deferiprone, 1-2 dimethyl-3-hydroxpyrid-4 one, DMHP, and CP20) has emerged as an orally active iron chelator with comparable efficiency to desferrioxamine in both short- and long-term clinical studies. Adverse side-effects, principally agranulocytosis and arthropathy, have raised doubts about its safety, and further trials are now planned to evaluate the incidence of these and other toxicities. Despite numerous studies, no other orally active agent has been shown in clinical trials to be as effective or as safe as L1. PMID- 9371988 TI - Erythrocytes. PMID- 9371987 TI - Recent advances in the management of thalassemia. AB - Although the current treatment of thalassemia with regular transfusions and assiduous chelation leads to a good quality of life and long survival, it is cumbersome and expensive. Various treatments have recently been explored. Bone marrow transplantation can cure thalassemia, but there was severe mortality in initial trials. It is safely successful only in patients in good clinical condition and with a compatible donor. Certain drugs, including azacytidine, butyrate, hydroxyurea, and erythropoietin may increase the production of fetal hemoglobin; their practical value is being explored. New potential oral iron chelators are under investigation. L1, the best evaluated, appears effective, but its potential toxicity remains undefined. PMID- 9371989 TI - Hematopoietic growth factors and the functions of blood cells. Commentary. PMID- 9371992 TI - Biology and potential clinical applications of flt3 ligand. AB - The flt3 ligand is a member of a small family of growth factors that stimulate the proliferation of hematopoietic cells. Other members of this family include Steel factor (also known as mast cell growth factor, stem cell factor, and kit ligand) and colony-stimulating factor 1. These proteins function by binding to and activating unique tyrosine kinase receptors. Both flt3 ligand and Steel factor stimulate the proliferation of early progenitor or stem cells. Neither of these factors exhibits much biologic activity by itself, but each factor can synergize with a wide range of other colony-stimulating factors and interleukins. One major difference between the two factors appears to be their effect on mast cells, which Steel factor stimulates, but flt3 ligand does not. Although flt3 ligand and Steel factor each act on early hematopoietic cells, differences in their activities suggest that they are not redundant and are both required for normal hematopoiesis. There are a number of clinical settings in which the flt3 ligand may prove quite useful. PMID- 9371991 TI - Physiology and preclinical studies of thrombopoietin. AB - Until recently, the molecular basis for the control of platelet production was largely unknown. In the past year, several groups have obtained complementary DNA for thrombopoietin, the substance first theorized nearly 40 years ago to regulate this process. Cellular and molecular studies have confirmed many of the properties previously attributed to this molecule, and have revealed some surprises. It is now clear that thrombopoietin is the critical regulator of platelet production. Detailed study of the molecule will likely yield important physiologic insights into megakaryocyte biology, and its application to states of iatrogenic and natural marrow failure will almost certainly provide therapeutic advances. PMID- 9371990 TI - Thrombopoietin and the humoral regulation of thrombocytopoiesis. AB - In 1994 four biotechnology research groups reported the isolation and cloning of the ligand for the cytokine receptor c-Mpl and showed it to be the long-sought regulator of platelet production, thrombopoietin. Thrombopoietin is a hematopoietic growth factor of 332 amino acids composed of an amino terminal domain homologous to erythropoietin and a highly glycosylated carboxyl domain. The erythropoietin-like domain is the functional domain, whereas the glycosylated domain appears to stabilize circulating thrombopoietin. Thrombopoietin stimulates both proliferation of progenitor megakaryocytes and their maturation to platelet producing megakaryocytes. Thrombopoietin induces dramatic increases in megakaryocyte number and platelet production in mice, indicating that it regulates both thrombopoiesis and megakaryocytopoiesis. Thrombopoietin also accelerates the recovery of platelets in myelosuppressed animals, suggesting that it will be clinically useful for the treatment of thrombocytopenia. PMID- 9371993 TI - Update on development of interleukin-11. AB - This paper reviews the recent studies of interleukin-11 gene expression and regulation, receptor and signal transduction, pharmacologic effects, and preclinical and clinical studies. Interleukin-11 is expressed in cells of mesenchymal origin and gene expression can be modulated by several inflammatory cytokines and agonists. The signaling pathways involved in cytokine induction of interleukin-11 gene expression vary between cell types. In vitro and in vivo studies reveal that interleukin-11 displays a wide spectrum of bioactivities including responses in hematopoietic and nonhematopoietic cells. Preclinical studies in animal models suggest that interleukin-11 may be useful in acceleration of the recoveries of both hematopoietic cells and gastrointestinal mucosal cells after cytoablative therapies. Several clinical studies have demonstrated interleukin-11 to be well tolerated and suggest interleukin-11 is a promising cytokine to prevent both neutropenia and thrombocytopenia in patients with cancer who are receiving chemotherapy. PMID- 9371994 TI - Use of hematopoietic growth factors for in vitro expansion of precursor cell populations. AB - The increasing availability of recombinant human hematopoietic growth factors for clinical use has encouraged the development of novel approaches to the manipulation of hematopoiesis. Of particular note are the various strategies that have been proposed for ex vivo expansion of primitive hematopoietic cells. The majority of these involve growth of hematopoietic cells enriched in primitive progenitors in stromal cell-free suspension culture systems supported by the addition of various combinations of hematopoietic growth factors. In this article, we review recent progress in this area together with potential clinical applications for this technology. PMID- 9371995 TI - Granulocyte colony-stimulating factor and granulocyte-macrophage colony stimulating factor in the treatment of myeloid leukemia. AB - Hematopoietic growth factors primarily used in patients with acute myelogenous leukemia after chemotherapy could reduce significantly the neutrophil recovery time in all patients. In high-risk acute myelogenous leukemia, trials also reported a reduction in the incidence of documented infections and early mortality rate. Thus in elderly patients with acute myelogenous leukemia and in high-risk patients with acute myelogenous leukemia the use of hematopoietic growth factors seems justified. Whether the rate of infections, particularly of life-threatening fungal infections, can be reduced by granulocyte colony stimulating factor or granulocyte-macrophage colony-stimulating factor after chemotherapy cannot be known without larger studies. A novel strategy in the treatment of acute myelogenous leukemia is the attempt to increase the growth fraction of clonal leukemic cells prior to administration of chemotherapeutic agents by the administration of hematopoietic growth factors. Evidence shows that hematopoietic growth factors enhance anti-leukemic activity of cytosine arabinoside against leukemic cells by recruitment of leukemic cells into cell cycle, an increase of intracellular cytosine arabinoside triphosphate:deoxcytidine 5' triphosphate pool ratios, or by an enhanced cytosine arabinoside incorporation into the DNA of acute myelogenous leukemia blasts. Whether these mechanisms lead to an increase in the complete remission rate and eventually to an improvement in survival must be answered in ongoing larger acute myelogenous leukemia trials using granulocyte colony-stimulating factor or granulocyte-macrophage colony-stimulating factor in such a setting. PMID- 9371996 TI - Hematopoietic growth factors in the treatment of the myelodysplastic syndromes. AB - Clinical trials with hematopoietic growth factors (granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interleukin-3, and erythropoietin) have been performed in patients with myelodysplastic syndromes. Absolute neutrophil counts can be readily raised to within the normal range by treatment with granulocyte colony-stimulating factor or granulocyte-macrophage colony-stimulating factor. Moderate increases in platelet counts have been reported for approximately 20% of patients during treatment with interleukin-3. Treatment with high-dose erythropoietin leads to an increase in hematocrit or decrease in transfusion needs in 15% to 20% of patients, but an improved response rate of approximately 40% has been reported for the combined treatment of erythropoietin with either granulocyte colony-stimulating factor or granulocyte macrophage colony-stimulating factor. Although meta-analyses of published phase I/II trials allow a rough estimation of response rates and an improved selection of patients who are most likely to respond, phase III trials have not yet been published. PMID- 9371998 TI - The use of erythropoietin in the enhancement of autologous transfusion therapy. AB - In the case of elective surgery requiring transfusion, preoperative autologous blood donation offers an attractive alternative to allogeneic blood transfusion. Although previously underutilized, autologous donation has become a standard of care in several elective surgical procedures, resulting in a significant increase in the percentage of blood collected nationally that is autologous. Potential candidates for autologous blood donation prior to elective surgery include any patient for whom blood type and crossmatch are requested, indicating a likelihood of requiring blood transfusion according to a maximum surgical blood ordering schedule. Utilization of autologous donation before elective surgery has increased with coordinated programs involving regional blood centers, hospital blood banks, information services, and physicians. The impact of physician ordering and autologous blood procurement practices on subsequent allogeneic blood transfusions must be understood in order to address the role of aggressive autologous blood procurement, including the role of recombinant human erythropoietin in blood conservation strategies. PMID- 9371997 TI - Erythropoietin in the treatment of anemia in chronic infectious, inflammatory, and malignant diseases. AB - The anemia associated with chronic infectious, inflammatory, and malignant diseases is characterized by a blunted erythropoietin response; for any given decrease in hemoglobin or hematocrit, the increase in serum or plasma erythropoietin is less than would be found in an equally anemic patient with iron deficiency. This observation provides a rationale for the use of recombinant human erythropoietin in the treatment of the anemia in these diseases. During the past year, new information has been reported on the pathophysiology of erythropoiesis in chronic infectious, inflammatory, and neoplastic diseases, and on the use of recombinant human erythropoietin for this anemia. This article reviews these developments. PMID- 9371999 TI - Optimization of peripheral blood stem cell collection. AB - Peripheral blood stem cells are increasingly used in lieu of marrow for hematopoietic support because of ease of collection and the rapid kinetics of recovery relative to bone marrow transplantation. More recently, it has been shown that adequate numbers of peripheral blood stem cells can be collected using growth factors alone without prior chemotherapy. By measuring CD34 or granulocyte macrophage colony-forming unit content of peripheral blood stem cell collections, mobilization technique, age, marrow disease, prior radiation, and prior chemotherapy regimens have been found to be important factors influencing the numbers of stem cells collected. However, interpatient variation in CD34 collections remains high and there are subgroups of heavily pretreated patients who will fail to mobilize sufficient numbers of stem cells to ensure rapid engraftment. The current challenge for clinical investigations is to improve methods for identifying such patients prior to collection and utilize new strategies for stem cell mobilization. The relative ease of collection and the rapid engraftment after myeloablative therapy suggest that peripheral blood stem cells will likely supplant marrow for both allogeneic and autologous transplantation in the next 5 years. PMID- 9372001 TI - Hematopoietic growth factors. PMID- 9372000 TI - The use of hematopoietic growth factors in treating HIV infection. AB - Human immunodeficiency virus infection causes multilineage hematopoietic defects. Defects in the production and function of CD4+ helper cells have been the focus of the majority of HIV research, but anemia, neutropenia, and thrombocytopenia are significant clinical problems as well. Bone marrow suppression is the dose limiting toxicity for a number of antiviral and prophylactic medications. Hematopoietic growth factors such as granulocyte colony-stimulating factor or granulocyte-macrophage colony-stimulating factor are used to optimize the delivery of antiretroviral and prophylactic therapy. Because of the expense involved, the most appropriate use of these hematopoietic growth factors remains a subject of intense investigation. This review focuses on recent experimental results. PMID- 9372002 TI - Targeted therapy for hematologic malignancies: has its promise been realized? PMID- 9372003 TI - Acute leukemia in children. AB - Childhood leukemia comprises approximately one third of cancer cases in children younger than 15 years of age. The incidence of childhood acute lymphoblastic leukemia is increasing. Outcomes have improved for childhood acute lymphoblastic leukemia over past decades and we may be at the dawn of improvement for childhood acute nonlymphoblastic leukemia. Technology has advanced to where submicroscopic bone marrow involvement may be detected in some patients with acute lymphoblastic leukemia in remission or with isolated extramedullary relapse by conventional criteria. Outcome may be predicted by in vitro chemosensitivity assays like the methyl thiazol tetrachium assay. Estimation of end-induction residual leukemic burden by polymerase chain reaction-based clonotypic assays has prognostic significance and provides a strategy for quantitative assessment of new therapeutic interventions. The relation of outcome to the intracellular accumulation of 6-thioguanine nucleotides provides an additional therapeutic avenue. Improved cure rates require increased attention to the health status of long-term survivors. PMID- 9372004 TI - Acute leukemia in adults. AB - The application of recent discoveries in the field of molecular oncology to acute myeloid and lymphoblastic leukemia has provided new insights into the pathogenesis and natural history of these diseases. Cytogenetic abnormalities and the detection of mutations or abnormal expression of certain oncogenes or tumor suppressor genes now provide powerful prognostic information to guide choice of therapy and prediction of response. Randomized trials of intensive postremission chemotherapy have now confirmed improved leukemia-free survival with the use of high-dose cytarabine or allogeneic or autologous bone marrow transplantation. Progress in the treatment of acute myeloid leukemia and acute lymphocytic leukemia in the elderly, where the prevalence of these diseases is likely to increase as our population ages, has been more modest. There is still a need for the evaluation of new treatment strategies in previously untreated patients with acute leukemia, despite the progress that has been reported during the past year. PMID- 9372005 TI - Non-Hodgkin's lymphoma. AB - The incidence of non-Hodgkin's lymphoma continues to rise. Molecular events in lymphocytes from individuals without lymphoma are found with increasing age and may represent early changes toward malignant transformation. Molecular, immunophenotypic, and histologic data have been used to propose a new classification system and several new entities have been identified. Localized, low-grade non-Hodgkin's lymphoma can be cured by radiotherapy, whereas patients with extensive disease experience a continuous remitting course. The effect of high-dose regimens is yet to be determined. Current therapy cures less than 50% of patients with advanced aggressive lymphoma and randomized multi-institutional trials using several regimens have shown similar outcomes. The addition of high dose therapy to patients in remission may offer a survival advantage to a high risk subset. Late complications of myeloablative therapy, including myelodysplasia and leukemia, are being increasingly recognized. A significant advance in the treatment of posttransplantation lymphoproliferative disorders using donor T cells was made and future applications of this approach are anticipated. PMID- 9372006 TI - Recent advances in Hodgkin's disease. AB - The treatment of Hodgkin's disease has long superseded our understanding of the pathogenesis of the disease. Recent work adds further evidence to the theory that the Epstein-Barr virus and the bcl2 oncogene play an etiologic role in certain histologic subtypes. Most patients who present with Hodgkin's disease today will be cured with radiation therapy, chemotherapy, or a combination of the two. However, any satisfaction with success in treating the disease should be tempered by the increasing recognition of morbid and potentially lethal complications. Secondary malignancies, cardiotoxicity, and other late effects continue to limit the quality and quantity of life after initial and salvage treatment. PMID- 9372007 TI - Mechanisms of resistance to therapy and tumor cell survival. AB - The failure to cure patients with cancer continues to be primarily because of the development of treatment resistance. Both normal and malignant cells die by either programmed cell death (apoptosis) or by cytolysis. Malignant cells have developed mechanisms of resistance that prevent them from entering the programmed cell death pathway as well as mechanisms of escaping immune recognition and cytolysis. These mechanisms include specific protective adaptations involving drug transport, metabolism, and target interactions. Malignant cells may also become resistant to therapy through alterations in genes encoding proteins involved in the initiation of apoptotic pathways. Finally, tumor cells may develop mechanisms to escape immune recognition, making them resistant to T-cell destruction. This article provides an overview of these mechanisms, with emphasis on published articles reported within the past year. PMID- 9372008 TI - Multiple myeloma and chronic lymphocytic leukemia. AB - New insights into the molecular biology of both multiple myeloma and chronic lymphocytic leukemia can potentially lead to new treatment modalities. For myeloma, its lack of CD34 expression can lead to a functional but less contaminated autograft for stem cell transplantation. Single or even double transplants are being used to treat high-risk or even relapsed disease. Cytokines, such as interleukin-6, appear to play a role in tumor growth and bony complications as well. The bisphosphonate drugs are now known to decrease skeletal complications. For chronic lymphocytic leukemia, the nucleoside analogues have produced impressive response rates in many patients. Cell surface markers and cytogenetic abnormalities continue to identify patients with poor prognoses. Myeloablative therapy remains controversial for this disease. PMID- 9372009 TI - Myelodysplastic syndrome. AB - Myelodysplastic syndrome continues to present a formidable clinical challenge. Despite considerable effort, no therapy apart from allogeneic bone marrow transplantation has been shown to prolong survival. Lack of effective therapy for myelodysplastic syndrome is of further concern given recent reports on the high incidence of myelodysplastic syndrome in patients undergoing intensive chemotherapy and radiation therapy for other malignancies. However, significant strides have been made in the past year toward understanding the molecular pathogenesis of some forms of myelodysplastic syndrome, as well as developing new approaches for therapy of myelodysplastic syndrome. This review highlights recent advances in the molecular genetics of myelodysplastic syndrome, including clonality analysis and identification of genes that are causally implicated in the pathogenesis of myelodysplastic syndrome; results from recent clinical trials for therapy of myelodysplastic syndrome using growth factors, chemotherapy or both; and recent literature on therapy-related myelodysplastic syndrome in intensively treated patients. PMID- 9372011 TI - Minimal residual disease. AB - The study of minimal residual disease has been fueled by the technologic advent of the polymerase chain reaction and basic developments identifying the genetic lesions involved in human malignancies. Thus far advances in identifying, cloning, and the subsequent polymerase chain reaction amplification of relevant genes have outpaced clinical studies designed to tell us the significance of minimal residual disease. It has become clear that the mere detection of minimal residual disease does not foretell relapse; thus, although the presence of minimal residual disease in acute lymphoblastic leukemia and acute prolymphocytic leukemia appears to be associated with a high risk of relapse, the presence of minimal residual disease in t(8;21) acute myeloid leukemia, chronic myeloid leukemia, and t(14;18) non-Hodgkin's lymphoma is not clearly associated with impending relapse. In most situations there is clearly a need for carefully controlled studies to evaluate the predictive value of minimal residual disease. PMID- 9372010 TI - Chronic myelogenous leukemia. AB - Chronic myelogenous leukemia is a clonal hematopoietic malignancy characterized by a balanced translocation between chromosomes 9 and 22 that results in the generation of an abnormal bcr/abl fusion protein with increased tyrosine kinase activity. This abnormal fusion protein has transforming activity for hematopoietic cells in vitro and causes chronic myelogenous leukemia-like myelopoiesis in mice. Chronic myelogenous leukemia progenitor cells display abnormalities in their interactions with bone marrow stroma, perhaps due to defective adhesion molecule function. Conventional therapies for chronic myelogenous leukemia include hydroxyurea, busulfan, or interferon. Treatment with interferon may prolong overall survival, especially in patients who achieve a cytogenetic response. Related donor marrow transplantation can result in long term survival in more than 65% of patients treated early in the course of disease. For patients without an available matched sibling donor, unrelated donor marrow transplantation or autologous marrow transplantation are alternative therapeutic options. PMID- 9372012 TI - The Ras signaling pathway and the molecular basis of myeloid leukemogenesis. PMID- 9372014 TI - Prognostic factors in leukemia and lymphoma. AB - The medical literature contains large numbers of reports on the clinical, laboratory, and biologic properties of the leukemias and lymphomas, the clinical relevance of which is largely unknown. This review focuses on the statistical criteria required for the design and interpretation of prognostic factor studies and discusses recent reports regarding potential pretreatment, treatment response, and biologic factors of leukemia and lymphomas that may, on further investigation, have applicability in predicting response to a given therapy. PMID- 9372013 TI - Hematopoietic cell proliferation and hematopoietic growth factors. AB - In vivo studies using hematopoietic growth factors in humans have more clearly defined the ability of these molecules to accelerate hematopoietic cell proliferation in postchemotherapy aplasia and constitutive marrow deficiency states. Studies applying combinations of two growth factors have been added. Investigation of negative regulators of hematopoietic cell proliferation has opened new approaches to protect against damage or loss of candidate stem cells in vitro or in vivo, as well as to selectively recruit malignant cell populations into cell cycle while protecting benign cells. New insights into the synergism of positive regulators of hematopoietic cell proliferation have come from a panoply of in vitro studies, underscoring the value of growth factors previously not associated with effects on hematopoietic cells that have now been found to confer significant synergism with known hematopoietic regulators. PMID- 9372015 TI - Hematologic malignancies. PMID- 9372016 TI - Thrombopoietin and its receptor, the proto-oncogene c-mpl. PMID- 9372017 TI - Multimerin. AB - Multimerin is a massive, disulfide-linked protein with a unique complementary DNA sequence. It is stored in platelets and the endothelium of blood vessels and is comprised of subunits linked by interchain disulfide bonds to form large, variably sized homomultimers. The multimerin subunits are derived from a common precursor protein, promultimerin, which undergoes proteolysis and extensive N glycosylation during biosynthesis. The complementary DNA sequence of multimerin indicates that multimerin is a novel protein, with Arg-Gly-Asp-Ser, coiled-coil, and epidermal growth factor-like domains. The C-terminal region of multimerin resembles the globular head domain of complement C1q and collagens type VIII and X. Multimerin is expressed by megakaryocytes and endothelial cells and stored within platelet alpha granules and endothelial cell Weibel-Palade bodies. Following cellular activation, multimerin is released and binds to these cells and the extracellular matrix. The function of this novel protein in hemostasis is under investigation. Recent studies have identified multimerin as a specific Factor V/Va binding protein that is complexed with Factor V within platelet alpha granules. PMID- 9372018 TI - Changing concepts in fibrinolysis. AB - New advances in molecular biology have prompted reevaluation of traditional concepts in fibrinolysis. Identification of novel cell surface activation receptors as well as a series of plasminogen/apolipoprotein(a) homologues suggests new potential mechanisms for controlled generation of the multifunctional protease plasmin. PMID- 9372019 TI - Heparin-induced thrombocytopenia and thrombosis. AB - Thrombocytopenia and thrombosis, recognized complications of heparin therapy, have long been thought to be antibody mediated. However, in vitro studies have failed to provide satisfactory explanations for platelet destruction and paradoxical thrombosis in patients with heparin sensitivity. Recently, several groups of investigators have shown that plasma from patients with heparin-induced thrombocytopenia and thrombosis contains IgG and IgM antibodies specific for complexes containing heparin and platelet factor 4, a heparin-binding protein normally contained in platelet alpha granules. These observations have provided new insights into the pathogenesis of this serious side-effect of heparin therapy and should point the way to improved diagnosis, prevention, and, possibly, treatment. PMID- 9372021 TI - Factor VIII inhibitors. AB - The development of a Factor VIII inhibitor, an antibody that blocks its procoagulant function, is one of the most serious complications of hemophilia A treatment. Similar antibodies are also recognized as a rare cause of bleeding in previously healthy individuals who develop autoimmune anti-Factor VIII antibodies. Recent studies have yielded important information about these antibodies in four different areas: better understanding of the incidence of inhibitors following Factor VIII treatment; identification of patients at highest risk of inhibitor formation; characterization of anti-Factor VIII; and the development of better therapies. PMID- 9372020 TI - Resistance to activated protein C caused by a factor V gene mutation. AB - Each year, approximately one in 1000 individuals suffers from venous thromboembolism. The pathogenesis of the disease is multifactorial and a thrombotic event is the result of a combination of genetic and circumstantial risk factors. Until recently, genetic defects could only be identified in a minority of thrombosis patients. The discovery of inherited resistance to activated protein C as a risk factor for thrombosis changed the situation for the better. In Western countries, activated protein C resistance is found in 20% to 60% of patients with thrombosis. Activated protein C resistance is caused by a single point mutation in the Factor V gene, leading to replacement of Arg(R)506 in the activated protein C cleavage site of Factor V with a Gln(Q). As a result, the activated protein C-mediated cleavage and inhibition of mutated Factor V (FV:Q506) is impaired, which leads to increased thrombin generation, a hypercoagulable state, and a life-long increased risk of thrombosis. PMID- 9372022 TI - Low molecular weight heparin, heparin, and warfarin. AB - Low molecular weight heparin is effective for the prevention and treatment of venous thromboembolism. Low molecular weight heparin has the practical advantage that it does not require anticoagulant monitoring and dose adjustment. The simplified therapy provided by low molecular weight heparin may allow many patients with venous thromboembolism to be cared for in an outpatient setting, with the potential for major savings in health care costs. In the setting of preventing venous thromboembolism after hip or knee replacement surgery, further cost-effectiveness studies are required to determine the ultimate clinical role of low molecular weight heparin. Extensive data document a consistent high rate of inadequate therapy when empirical or intuitive approaches are used to administer intravenous unfractionated heparin in patients with venous thromboembolism or cardiovascular disease. A validated protocol should be used for intravenous heparin treatment. The evidence is accumulating that warfarin is more effective than aspirin for preventing thromboembolism in patients with atrial fibrillation. PMID- 9372023 TI - Hirudin and hirudin analogues as new anticoagulant agents. AB - Recombinant hirudin and hirudin analogues constitute interesting new antithrombotic agents that have distinct advantages over heparin. These agents specifically inhibit thrombin and all of its actions and also suppress further thrombin generation. As opposed to unfractionated heparin, hirudin and hirulog effectively suppress clot-bound thrombin, making these agents of particular interest in the treatment of arterial thrombosis, for example, following thrombolysis or percutaneous transthoracic angioplasty. The recent data derived from clinical trials supporting the use of hirudin and hirulog in the prevention and treatment of thrombotic diseases are reviewed here. PMID- 9372024 TI - Treatment of the hemophilias. AB - The treatment of hemophilia and conditions that frequently afflict hemophilic patients, such as arthropathy, HIV infection, and viral hepatitis, are discussed. Long-term prophylaxis with Factor VIII or IX is very successful at preventing disabling arthropathy. Much research is being done on gene therapy and prolonged periods of Factor VIII and IX expression have already been achieved in animals. In HIV-seropositive hemophilic patients the CD4 count appears to decline more slowly in patients treated with higher purity than with lower-purity products. Thermoresistant non-lipid-enveloped viruses, such as parvovirus, do not become inactivated by the currently used virucidal methods. PMID- 9372025 TI - Congenital thrombocytopenias. AB - Congenital thrombocytopenias are rare bleeding disorders but must be included in the differential diagnosis when investigating a young infant with chronic thrombocytopenia. Several of these syndromes have associated defects of immune, renal, or skeletal systems in addition to thrombocytopenia. These can be categorized into two groups depending on the presence or absence of bone marrow hypoplasia. The majority of these disorders are associated with a mild bleeding tendency and thus may be missed until the affected individuals experience excessive postoperative or posttraumatic hemorrhage. In adults, this entity must be considered when evaluating a patient with thrombocytopenia who is unresponsive to the medical management of immune thrombocytopenia. Other than platelet transfusion, no specific therapy is available for these disorders. A test dose of desmopressin may be attempted in a nonbleeding patient (to see if it will shorten the bleeding time) prior to using it for treatment of a bleeding episode or surgical prophylaxis. Bone marrow transplantation may prove curative in a select group of thrombocytopenic syndromes. PMID- 9372026 TI - Disseminated intravascular coagulation. AB - Disseminated intravascular coagulation is the result of a severe underlying disorder that initiates massive activation of the coagulation system. It is always a symptom of the underlying disorder. These disorders may be as varied as meningococcemia and abdominal aortic aneurysm. Disseminated intravascular coagulation is a clinical diagnosis. Once the clinical impression has been considered, a small number of readily available tests will substantiate the diagnosis. Further testing is probably not necessary and certainly not cost effective. Therapy for disseminated intravascular coagulation requires 1) the correction of the underlying problem, either by drainage of an abscess for sepsis, evacuation of the uterus in an obstetric catastrophe, or treatment of septicemia with antibiotics; and 2) the concomitant restoration of the circulatory system, perfusion, blood pressure, and electrolyte balance. Other forms of therapy are available but are quite secondary to these two. Success depends on the ability to recognize and correct the cause. PMID- 9372027 TI - Hemostasis and thrombosis. PMID- 9372028 TI - Immune recovery after bone marrow transplantation. AB - Bone marrow transplantation usually entails the ablation of the recipient's immune system. The recovery of immunity after marrow transplantation is a complex process dependent on a number of pre- and posttransplantation factors. Many of the basic concepts of immune reconstitution after transplantation have been elucidated over the past decade. Recent developments focus on attempts to manipulate immune recovery in the posttransplantation period. Soluble mediators of both B-cell and T-cell number and function have been tested in both preclinical and clinical transplant models. The direct administration of T cells after transplantation can be used to augment the immune response to infection, lymphoproliferative disease, and malignancy. PMID- 9372029 TI - Umbilical cord blood biology and transplantation. AB - Human cord and placental blood provides a rich source of hematopoietic stem cells. On the basis of this finding, umbilical cord blood stem cells have been used to reconstitute hematopoiesis in children with malignant and nonmalignant diseases after treatment with myeloablative doses of chemoradiotherapy. Early results show that a single cord blood sample provides enough hematopoietic stem cells to provide short- and long-term engraftment, and that the incidence and severity of graft-versus-host disease has been low even in HLA-mismatched transplants. These results are encouraging enough to embark on the large-scale banking of cord blood for future allogeneic and autologous stem cell transplantation, to promote studies on the unique properties of fetal and neonatal hematopoiesis, to study the immunologic properties of cord blood cells, and to initiate investigations on gene transfer into human cord blood cells for future gene therapy trials. This review briefly summarizes the current knowledge on cord blood transplantation as well as the future development of research on this unique source of hematopoietic stem cells. PMID- 9372030 TI - Gene transfer for the therapy of hematologic malignancy. AB - Gene transfer has allowed a number of biologic issues in the therapy of hematologic malignancy to be addressed. In autologous bone marrow transplantation, gene marking studies have shown that infused marrow contributes to relapse in acute myeloid leukemia, neuroblastoma, and chronic myeloid leukemia. In addition, double gene marking with distinguishable retroviral vectors has allowed comparison of purging techniques and the ability of different sources of stem cells to repopulate. In allogeneic bone marrow transplantation, genetically modified T cells have proven valuable for the prophylaxis and treatment of viral diseases and may be of use to treat disease relapse. Gene transfer is also being used to modify tumor function, enhance immunogenicity, modify function of adoptively transferred immune system cells, and confer drug resistance to normal hematopoietic stem cells. PMID- 9372032 TI - Blood stem cell allografting. AB - The emergence of peripheral blood stem cells as the preferred source of autologous rescue in high-dose therapy has indicated their potential benefits for allogeneic transplantation. Adequate mobilization with minimal side-effects can be achieved in normal donors using a short course of G-CSF. Allogeneic stem cells provide long-term engraftment that appears to be more rapid than that seen with marrow, but this observation awaits confirmation in a prospective randomized study. The cellular composition of stem cell and bone marrow allografts is very different, with greater numbers of CD34+ progenitors, T lymphocytes, and natural killer cells in stem cell harvests. Although infused T-cell numbers are increased, no difference in acute graft-versus-host disease has been documented between stem cell and marrow allografts. Any differences in chronic graft-versus host disease or relapse risk await longer follow-up. It is likely that the use of allogeneic stem cells will expand both in matched sibling and mismatched transplantation. PMID- 9372031 TI - Donor leukocyte transfusions for leukemic relapse. AB - Treatment of recurrent leukemia after bone marrow transplantation with the transfusion of lymphocytes from the marrow donor has been successful in a majority of patients with chronic myelogenous leukemia and a minority of patients with acute myeloid leukemia and myelodysplastic syndrome. It has been disappointing in patients with acute lymphoblastic leukemia and in advanced stages of chronic myelogenous leukemia. In chronic-phase chronic myelogenous leukemia remissions were of good quality and the actuarial relapse rate was less than 20% at 3 years. In acute leukemias remissions were less durable. Graft versus-host disease and marrow aplasia were the major complications of this form of treatment. In patients with marrow aplasia hematopoiesis could be restored by infusion of donor marrow without further conditioning treatment. Preceding or concomitant treatment with interferon alpha is not essential for a response, but the exact role of interferon alpha remains to be determined in a randomized study. Similarly, the best time for treatment remains to be defined. Treatment of cytogenetic and molecular recurrence of chronic myelogenous leukemia is most effective in preventing marrow aplasia, but a few patients may be treated unnecessarily, for some cytogenetic recurrences may remit spontaneously. The mechanism of the graft-versus-leukemia reaction is still not clear. Effector cells and target antigens remain to be defined. Observations are compatible with a graft-versus-host reaction directed against minor histocompatibility antigens presented at the cell surface of hematopoietic cells, but reactions against leukemia-specific antigens are possible. Future studies will focus on differences of reactions against possible leukemia-specific antigens and histocompatibility antigens on hematopoietic cells and cells of other organs. PMID- 9372033 TI - Autografting for chronic myelogenous leukemia. AB - Two thirds of patients with chronic myelogenous leukemia do not have suitable donors for allogeneic transplantation. As for other leukemias, autografting may potentially be curative, because normal Ph- hematopoietic stem cells persist in the marrow and blood of patients with chronic myelogenous leukemia. Several studies indicate that use of unpurged autologous blood or marrow grafts may extend survival for patients undergoing transplantation in chronic phase. Ex vivo or in vivo purging of chronic myelogenous leukemia marrow or blood prior to autografting may result in increased cytogenetic remissions after transplantation in those patients in whom the Ph+ clone can be eliminated. However, when the Ph+ clone cannot be eliminated, use of purged rather than unpurged autografts provides no advantage and may be associated with increased graft failure. Although sustained cytogenetic remissions have not been observed, autografting may result in a plateau in the survival curve not observed with conventional chemotherapy. Efforts are currently directed toward developing improved methods of purging as well as posttransplantation treatments directed against leukemic cells persisting after myeloablative therapy. PMID- 9372034 TI - Marrow transplantation from unrelated donors. AB - The use of an HLA-compatible unrelated donor is an option for patients who require an allogeneic transplant but lack a family member match. Grafts from unrelated volunteer donors have provided long-term disease-free survival for a variable proportion of patients, depending on degree of HLA matching with the donor, patient's disease, disease stage, and age. The number of volunteers in marrow donor registries worldwide has increased to more than 2.5 million. The number of unrelated donor transplants facilitated by the US National Marrow Donor Program alone will exceed 900 this year. Progress in HLA-typing technology results in a more precise definition of donor and recipient matching and new assays have been developed with initial success to measure alloreactive T-cell precursors for selection of donors with less antihost reactivity. Prevention and treatment of graft failure, graft-versus-host disease, opportunistic infections, and Epstein-Barr virus-associated lymphoproliferative disease remain a challenge. PMID- 9372035 TI - Stem cell isolation. AB - High-dose chemotherapy with autologous hematopoietic progenitor cell support is increasingly used to treat a variety of malignant diseases. A drawback of this technique is the potential for infusing clonogenic tumor cells with the autograft, producing relapse of the disease in the patient. The use of positive selection techniques to isolate stem cells and thus reduce or eliminate tumor cell contamination has been extensively studied over the past few years. Preliminary clinical results have demonstrated that these procedures deplete 2 to 7 logs of tumor cells and do not impair engraftment. It is too early to assess the ultimate clinical benefit of this strategy. Additional applications of CD34 selection include ex vivo expansion of and gene transfer into hematopoietic progenitor cells and T-cell depletion of allogeneic grafts to reduce the incidence of graft-versus-host disease. PMID- 9372037 TI - Transfusion medicine. PMID- 9372036 TI - Molecular methods for monitoring malignant disease after bone marrow transplantation. AB - Significant progress has been made over the past few years in the characterization of genetic defects responsible for the development of leukemia. In addition to contributing to our understanding of the biology of malignancy, defined genetic lesions may serve as markers of the abnormal cells. Such markers are useful for diagnostic purposes and for the detection of residual malignancy in patients after therapy or as contamination in peripheral blood or bone marrow harvests. In particular, detection of tumor-specific lesions or other tumor associated markers by the techniques of cell and molecular biology has prompted a reevaluation of the definitions of remission and relapse. PMID- 9372038 TI - Can Creutzfeldt-Jakob disease be transmitted by transfusion? AB - The transmissible agent of Creutzfeldt-Jakob disease, a dementing neurodegenerative disorder, is present in many tissues of the body, even though its pathologic consequences are confined to the brain. Experimental animal models of the disease have shown that blood (most probably the leukocyte component) can be infectious in both the clinical and preclinical incubation stages of the disease, and there are also a few reported isolations of the agent from whole blood, buffy coats, or serum from humans with Creutzfeldt-Jakob disease. Despite this potential for blood-borne iatrogenic infection, epidemiologic studies do not support the contention that the administration of blood, blood components, or blood derivatives transmits the disease; in particular, not one of nearly 2000 patients who have been studied during the past two decades has been shown to have acquired the disease from a blood donor who later died of Creutzfeldt-Jakob disease. This fact does not diminish our responsibility to preclude such an occurrence from happening in the future, and will require an unremitting effort to screen from the blood donor population all individuals with a higher than average risk of harboring the infectious agent; namely, donors with neurologic disease, a family history of neurologic disease, or a history of events that have been identified as leading to iatrogenic Creutzfeldt-Jakob disease, such as neurosurgical procedures involving dura mater homografts or treatment with native pituitary hormones. PMID- 9372039 TI - Febrile nonhemolytic transfusion reactions to platelets. AB - Although febrile nonhemolytic transfusion reactions to erythrocytes and platelets are not life threatening, the clinical symptoms associated with them cause discomfort for the patient, result in the use of premedicative drugs, and utilize nursing and laboratory resources. For many years it was assumed that febrile nonhemolytic transfusion reactions were caused by an interaction between leukocyte antibody in the patient's plasma and leukocytes present in the transfused product. Thus prevention has focused on the removal of leukocytes from the blood product by centrifugation or filtration just prior to transfusion. Recent data suggest that most febrile nonhemolytic transfusion reactions to platelets do not involve an immune-mediated event but are caused by the accumulation of biologic response modifiers in the platelet product during storage. Potential biologic response modifiers that have been investigated include histamine, lipids, complement fragments, and cytokines. The concentrations of these substances have been shown to increase in erythrocytes or platelet products or both during storage, and there is some clinical evidence that supports an association between elevated cytokine levels and the risk of reaction. If biologic response modifiers play a major role in febrile nonhemolytic transfusion reactions to platelets, then interventions to prevent these reactions should focus on ways to stop production of these substances or on mechanisms to remove these substances from the platelet product before transfusion. Possible interventions include prestorage leukoreduction, plasma removal from the platelet product before transfusion, and reduction of the platelet storage period to 3 days. Clinical studies to identify the most effective approach for preventing febrile nonhemolytic transfusion reactions have not yet been reported. PMID- 9372041 TI - Causes of refractoriness to platelet transfusion. AB - Platelet refractoriness is a multifactorial problem that often leads to aggressive measures in an attempt to treat a thrombocytopenic patient. Identification of the underlying causes should allow for prevention and management regimens to improve both transfusion practice and patient outcome. A number of clinical studies have evaluated the relative importance of the various causes of refractoriness. Unfortunately, most are significantly compromised by uncontrolled confounding factors. The causes can be broken down into three categories based on the source of the problem: clinically determined, patient related, or blood bank determined. This breakdown can help to identify appropriate prevention and circumvention measures. Additional causes worthy of increased attention are the platelet transfusion trigger and the tendency for prophylactic transfusion. Improvements in transfusion practice may offer the greatest hope for limiting the complications of platelet transfusion and refractoriness. PMID- 9372040 TI - Strategies for viral inactivation. AB - The risk of transmission of viruses and other pathogenic organisms by blood can be reduced but not eliminated through donor selection and screening methodologies. The safety of blood derivatives prepared from plasma pools from thousands of donors requires virus inactivation, without which transmission rates approach certainty and with which safety can exceed that of single-donor products. Current inactivation methods have reduced and possibly eliminated the transmission of enveloped viruses, eg, hepatitis B and C viruses and HIV; newer methods, when coupled with existing methods, have the likelihood of providing products whose safety matches that of any pharmaceutical product. Success with the virus inactivation of pooled blood products has fostered research into inactivation methods that are compatible with erythrocyte concentrates and platelet concentrates. The most advanced of these employ light-activatable compounds. If successful, virtually all blood products can be free from transmitting viruses and other pathogenic organisms. PMID- 9372043 TI - Transfusion medicine. PMID- 9372042 TI - Bone marrow transplantation. PMID- 9372044 TI - Rethinking research management practices. PMID- 9372045 TI - American Society of Clinical Oncology guidelines for the use of hematopoietic colony-stimulating factors. AB - The hematopoietic colony-stimulating factors have been introduced into clinical practice as additional supportive measures that can reduce the likelihood of neutropenic complications due to chemotherapy. Clinical benefit has been shown, but the high cost of colony-stimulating factors has led to concern about their appropriate use. The American Society of Clinical Oncology has established evidence-based, clinical practice guidelines for the use of colony-stimulating factors in patients who are not enrolled in clinical trials. An expert multidisciplinary panel reviewed the clinical data documenting the activity of colony-stimulating factors. For each common clinical situation, the panel formulated a guideline to encourage reasonable use of colony-stimulating factors to preserve effectiveness but discourage excess use when little marginal benefit is anticipated. Outcomes considered in evaluating colony stimulating factor benefit included duration of neutropenia, incidence of febrile neutropenia, incidence and duration of antibiotic use, frequency and duration of hospitalization, infectious mortality, chemotherapy dose intensity, chemotherapy efficacy, quality of life, colony-stimulating factor toxicity, and economic impact. To the extent that these data were available, the panel placed greatest value on survival benefit, reduction in rates of febrile neutropenia, decreased hospitalization, and reduced costs. Lesser value was placed on alterations in absolute neutrophil counts. PMID- 9372046 TI - Current concepts about neutrophil granule physiology. AB - During the past decade it has become clear that neutrophil granules are not simple bags of proteolytic and microbicidal substances. Their membranes contain proteins of paramount importance for the neutrophil to carry out its function as the body's primary mobile phagocyte. It has recently become evident that the heterogeneity of neutrophil granules is much wider than previously thought and that a highly mobilizeable organelle, termed the secretory vesicle, may play a key role in modulating the neutrophil's surface protein profile in response to chemotactic factors. Clearly correct targeting of both membrane and matrix proteins into these different mobilizeable organelles is important for optimal function of the neutrophil. The expanding knowledge of protein targeting into granules and of control of their subsequent mobilization under the specialized conditions of rolling, adhesion, diapedesis, and phagocytosis is the subject of this review. PMID- 9372047 TI - Peptide transport in antigen presentation. AB - The TAP1/2 complex translocates peptides from the cytosol into the endoplasmic reticulum. In the rat, TAP polymorphism affects the pool of peptides presented by major histocompatibility complex class I molecules, whereas in mouse and humans the functional consequences of observed structural polymorphism have not yet been determined. Peptide binding to TAP precedes ATP binding, and ATP hydrolysis is required to release and translocate peptides. Cytosolic peptides entering the class I pathway via the TAP complex may differ significantly in size and sequence. Not all peptides that are able to bind to TAP can be translocated into the endoplasmic reticulum, and TAP-binding affinity does not directly correlate with antigenicity of the peptide. Most translocated peptides are released from the endoplasmic reticulum by an incompletely defined ATP-dependent mechanism. TAP interaction with class I molecules stimulates peptide binding and transport by TAP and may also facilitate efficient loading of class I with peptides. Pathogenic microorganisms, such as herpes simplex virus, may encode inhibitors of TAP-mediated peptide transport in order to evade immune surveillance. PMID- 9372048 TI - Stress- and mitogen-activated signal transduction in hematopoietic cells. AB - The ability of an organism to respond to its environment is critical to survival. The mechanisms by which cells recognize and interpret different stimuli vary enormously and can be manifested by proliferation, differentiation, apoptosis, or altered metabolic activity. Recently, a series of signaling cascades was identified that links actions on the cell surface with activation or suppression of transcription. These signals are transmitted via phosphorylation and include the stress-activated protein kinases and the mitogen-activated protein kinases. This review describes these cascades in reference to the hematopoietic cell lineages. PMID- 9372049 TI - Apoptotic signaling in lymphocytes. AB - Two families of cell surface receptors are integral to the control of lymphocyte survival and programmed cell death (apoptosis): the tumor necrosis factor receptor family and the CD28/CTLA4 family. Tumor necrosis factor receptor family members bind a related collection of ligands (the tumor necrosis factor family) that can either induce or inhibit cell death. Two of the tumor necrosis factor receptor family members, tumor necrosis factor receptor 1 and Fas, have been implicated in the termination of immune responses through their ability to induce apoptosis. A number of cytoplasmic proteins implicated in signal generation by these receptors recently have been identified. These proteins fall into several related classes sharing intriguing structural motifs. The CD28 and CTLA4 molecules share at least two extracellular ligands and signaling through the two receptors appears to determine the apoptotic sensitivity of activated T cells. The effects of CD28 and CTLA4 on cell survival are dependent on T-cell antigen receptor engagement, providing a potent mechanism for clonally specific T-cell expansion or deletion. The study of the apoptotic pathways in lymphocytes has led to a better understanding of the mechanisms of autoimmune disease and serves as a model system for the study of the regulation of cell survival and tissue homeostasis. PMID- 9372050 TI - Behavioral aspects of neutrophil motility. AB - The ability to move is one of the most basic and critical functions of the neutrophil. The neutrophil changes its shape from round to highly polar and glides along the surface, pausing every 45 to 60 seconds to reestablish its direction. Iterations of this sequence of small-scale motion, or shape change, sum to form the large-scale trajectories that have fascinated many investigators over the years. Recent studies of neutrophil motion using novel stimuli and high temporal resolution measurements of motion have unveiled extremely regular behaviors with periods of approximately 8 seconds. These and previous studies suggest that neutrophil shape change consists of high-frequency ruffling and lower-frequency development of morphologic polarity. These components of shape change are superimposed, because of separate cytoskeletal mechanisms, and are regulated differently. The fundamental motor of the neutrophil seems to be nonrandom and driven by two clocks, one with a highly regular period of 8 seconds and another with a period of 45 to 60 seconds. PMID- 9372051 TI - Phospholipid signaling in leukocytes. AB - Major advances have been made recently concerning mechanisms involved in the generation of second messengers derived from agonist-induced phospholipid metabolism. New functions for well-known GTPases have been described, and other well-characterized proteins have been identified as regulators of phospholipases and phosphokinases. ARF and Rho have been recently identified as activators of phospholipase D. Rho regulates not only phospholipase D but also phosphatidylinositol 4-phosphate 5-kinase. Both beta gamma- and alpha-subunits of heterotrimeric G-proteins have been described as regulators of a new isoform of phosphatidylinositol kinase. Phosphatidylinositol transfer protein is now recognized as an essential requirement for both phospholipase C gamma and C beta isozymes to hydrolyze phosphatidylinositol 4,5-bisphosphate in cells. Some of these proteins such as ARF, Rho, and phosphatidylinositol transfer protein have well-defined roles in vesicular traffic and in cytoskeletal reorganization, thus bringing the field of signal transduction closer to the world of vesicular traffic as well as the cytoskeleton. PMID- 9372052 TI - Regulation of azurophil granule-associated serine protease genes during myelopoiesis. AB - During myelopoiesis, the primary or azurophil granules are synthesized at the promyelocyte stage of development. The biogenesis of these granules requires the coordinated regulation of a large number of genes that comprise the constituent proteins of the granules themselves. The genes encoding the granule-associated proteins appear to be regulated primarily at the level of gene transcription; that is, most of the granule genes appear to be transcriptionally activated at the beginning of the promyelocyte stage and are transcriptionally repressed at the transition to myelocytes. The cis-acting DNA elements and trans-regulatory factors that control the regulation of granule genes are just beginning to be defined. The granule-associated genes are dispersed throughout the genome; however, several of the serine protease genes expressed in these granules are tightly clustered and the tight clustering may play an important role for their regulation. Recent transgenic studies suggest that DNA elements required for myeloid-specific targeting may be located just upstream from or very near to the granule genes themselves. DNA elements similar to the globin locus control region will probably play a role in the expression of these genes, although locus control elements have not yet been defined for any azurophil granule genes. Future studies directed at defining these key regulatory elements will enhance our understanding of the molecular events that underlie myeloid development. PMID- 9372053 TI - Calcium and signal transduction in granulocytes. AB - During activation, blood cells experience changes in intracellular free calcium levels ([Ca2+]i) that are associated with signal transduction events. In granulocytic cells, changes in [Ca2+]i have been associated with multiple functions, including activation of cellular kinases and phosphatases, degranulation, phagosome-lysosome fusion, regulation of cytoskeletal binding proteins, transcriptional control, and modulation of surface receptors. This review discusses the general role played by [Ca2+]i in granulocytic leukocyte signal transduction, with a special emphasis on recent developments in the field of calcium signaling to and from integrins and the regulation of cell adhesion and motility by [Ca2+]i. PMID- 9372054 TI - Advances in leukocyte differential and peripheral blood stem cell enumeration. AB - Automated leukocyte differential counting has resulted in a marked improvement of the precision of leukocyte subclass enumeration. With advancement of this technology, algorithms have been developed to identify samples that require manual microscopic review. Complex flagging algorithms permit acceptable false positive rates with effective use of microscopic review to identify significant morphologic abnormalities. Current literature indicates that the leukocyte differential is a poor case-finding index in both outpatient and inpatient populations. Development of highly automated technology has led to test over utilization because of ease of performance despite recognized limitations in identifying clinically significant abnormalities. Enumeration of hematopoietic stem cells in harvested peripheral blood or bone marrow is critical for determining whether transplanted cells will produce adequate engraftment. Hematopoietic precursors express the CD34 antigen, are present as rare events in unmobilized blood, and are found in increased numbers after mobilization with chemotherapy with or without G-CSF. Flow cytometric detection of CD34+ cells is more rapid and precise than cell culture techniques and results are available in time to determine if further cell harvesting procedures will be necessary. CD34+ cell concentrations correlate with granulocyte-macrophage colony-forming unit counts as well as with time to engraftment. Although intralaboratory precision in measuring these infrequent events may be good, comparisons between different laboratories using aliquots of the same sample have yielded more variable results. Problems in determining precise and reproducible CD34+ cell concentrations may be due to nonspecific antibody binding, insufficient signal intensity of true positive events, differences in monoclonal antibodies and their fluorochrome conjugates, or failure of the total absolute leukocyte count to accurately reflect the population used for CD34 analysis. PMID- 9372055 TI - The central role of the CD40-ligand and CD40 pathway in T-lymphocyte-mediated differentiation of B lymphocytes. AB - This review summarizes recent findings concerning the role of CD40-ligand and CD40 interactions in B-cell differentiation. CD40-ligand on helper CD4+ T lymphocytes interacts with CD40 on B cells and directs the selection and differentiation of clones of B lymphocytes to generate specific antibody dependent immune responses. CD40-ligand is necessary for normal B-cell differentiation and plays several distinctive roles in this multistage process. The CD40 signaling pathway that normally regulates B-cell death appears to be usurped by the Epstein-Barr virus to mediate B-cell transformation. PMID- 9372057 TI - Apoptosis of neutrophils. AB - Neutrophils are the most abundant leukocytes and serve as a first line of defense against infectious microorganisms. For this purpose, neutrophils contain granules filled with proteolytic and other cytotoxic enzymes. Neutrophils have the shortest lifespan of all leukocytes. To prevent senescent neutrophils from releasing their toxic contents into the surrounding tissues, these cells become apoptotic and are then internalized by tissue macrophages. Recent studies have revealed more details about effects of cytokines on neutrophil apoptosis and on the uptake of apoptotic neutrophils by macrophages. In addition, the intracellular events leading to apoptosis are slowly being unraveled. PMID- 9372056 TI - Role of interleukin-6 in macrophage function. AB - Interleukin-6 is a multifunctional cytokine important for host defense. Macrophages are potent producers of interleukin-6. Conversely, interleukin-6 acts on monocytes to induce their differentiation to macrophages. This paper reviews the in vivo roles of interleukin-6 and nuclear factor for interleukin-6 expression that have been revealed by gene targeting as well as recent progress in understanding the interleukin-6 gene regulation and signaling pathway in macrophages. PMID- 9372058 TI - Leukocytes. PMID- 9372059 TI - The dual pathogenesis of paroxysmal nocturnal hemoglobinuria. AB - Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired blood disease with distinct and rather peculiar characteristics that have puzzled hematologists for more than a century. PNH cells are deficient in a set of membrane proteins that have in common a glycolipid anchor. We refer to this combination of deficiencies as the PNH abnormality or the PNH phenotype. Biochemical analysis has recently made it possible to pinpoint the metabolic block in PNH cells to an early step in the biosynthesis of the glycolipid anchor. This block is due in turn to the deficiency of a protein, called PIG-A, which is encoded by an X-linked gene. Expression cloning of the PIG-A gene has been followed by the identification in patients with PNH of somatic mutations in this gene that inactivate or impair the function of the PIG-A protein. These findings explain in full the molecular basis of the PNH abnormality, but they do not explain how the PNH clone, which is biochemically defective, can expand to the extent of contributing a substantial proportion of the patient's hematopoiesis. Thus a second factor is required to explain the pathogenesis of PNH. This is most likely the coexistence of an element of bone marrow failure that produces, paradoxically, a survival or growth advantage for the PNH clone. The notion that the injury causing failure of normal stem cells spares selectively cells with the PNH phenotype is supported by a number of observations, including the finding of multiple independently arisen PNH clones in patients with PNH. PMID- 9372060 TI - Human parvovirus B19 infection. AB - Human parvovirus B19 shows remarkable tropism for human erythroid progenitor cells. The pathogenesis of disease resulting from infection is a dynamic between the viral suppression of erythropoiesis and the host's ability to mount an effective immune response. Understanding this process has led to strategies for treating chronic anemia in persistently infected patients and may result in the development of a vaccine to prevent infection. PMID- 9372061 TI - Molecular basis of sickle cell-endothelial cell interactions. AB - Adherence of sickle erythrocytes to microvascular endothelium is posited to initiate or contribute to sickle cell vaso-occlusive pain episodes. Adherence and occlusion in vivo may depend on hemodynamics interacting with plasma, erythrocyte, and endothelial cell factors. Four receptor-mediated adherence pathways have been described to date: adherence mediated by high molecular weight von Willebrand factor multimers bridging glycoprotein lb-like and integrin receptors on sickle cells and similar receptors on endothelial cells; thrombospondin bridging CD36 on sickle reticulocytes and the alpha v beta 3 integrin on large-vessel endothelial cells or alpha v beta 3 and CD36 on microvascular endothelium; binding of sickle reticulocyte alpha 4 beta 1 receptors to vascular cell adhesion molecule 1 expressed on endothelial cells stimulated by cytokine or double-stranded RNA viruses; and binding of sickle cells to endothelial cell-associated fibronectin via sickle reticulocyte alpha 4 beta 1 activated by phorbol ester or interleukin-8. The significance of these adherence pathways in sickle cell vaso-occlusion is discussed. PMID- 9372062 TI - Orally active iron chelators in the treatment of iron overload. AB - Data from several trials have provided evidence for the efficacy of deferiprone in the treatment of iron overload in thalassemia major. Deferiprone has now been shown to induce sustained decreases in tissue iron to concentrations that are associated with survival free of the complications of iron overload in deferoxamine-treated patients. Despite this evidence of efficacy, the risk of agranulocytosis mandates a careful evaluation of the risk of this drug in patients willing and able to use deferoxamine. The incidence of agranulocytosis associated with deferiprone is under study in a prospective multicenter trial in Canada, Italy, and the United States, under corporate sponsorship by Apotex Research in Canada. The results of this study should determine the risk associated with the use of this agent and may provide the data required for a US Food and Drug Administration decision regarding licensing of this agent for the treatment of iron overload, a goal supported by investigators worldwide. PMID- 9372063 TI - Advances in molecular diagnosis of inherited hemoglobin disorders. AB - Molecular diagnosis for inherited disorders of hemoglobin production has been driven largely by the need for improved prenatal diagnosis. In turn, DNA-based testing has engendered better methods of fetal sampling. The sensitivity of DNA based testing was increased tremendously by the polymerase chain reaction. Currently there are numerous polymerase chain reaction-based methods for diagnosing specific mutant globin alleles and detecting unknown mutations. These rely on restriction analysis, allele-specific hybridization or amplification, alterations in electrophoretic mobility, and DNA sequence analysis. The advantages and disadvantages of each are important to their specific application. The reverse dot blot method, with its capability for screening multiple alleles with a single hybridization reaction, is currently the most advantageous method for prenatal and routine clinical diagnosis. PMID- 9372064 TI - Treatment of sickling disorders. AB - Sudden death in military recruits with sickle cell trait appears to be related to hyperthermia and its consequences and can probably be prevented by use of sensible precautions and heightened awareness of the risk. Sickle cell disease can be treated by decreasing the proportion of sickle cells through transfusion; indications and pathophysiology of such transfusions are beginning to become clear. Sickle cell disease can be prevented if erythrocytes can be prevented from sickling. Dilution of hemoglobin S within erythrocytes, by stimulating fetal hemoglobin production, increasing cell water, or inducing iron deficiency, can achieve that goal in some patients, but risks and benefits of such treatment are still incompletely understood. PMID- 9372065 TI - Current issues in iron deficiency. AB - This brief review of developments relating to iron deficiency during the past year covers three main areas: iron supplementation, the regulation of iron absorption, and the use of the serum transferrin receptor for the assessment of iron status. The intermittent administration of iron supplement once or twice weekly rather than daily has been advocated by international health agencies in recent years, but radioiron absorption studies in human subjects have failed to demonstrate any absorptive advantage of the intermittent schedule. The value of prophylactic iron supplementation in elderly blood donors was evaluated and shown to offer limited benefit in maintaining donation frequency. A recent model of the regulation of iron absorption involving erythropoietic and store regulators is discussed and a recent article indicating a potential non-hematopoietic effect of hematopoietic growth factors on iron absorption by the gastrointestinal mucosal cell is reviewed. A new measure of functional iron deficiency, namely the serum transferrin receptor, is discussed, with particular reference to its mechanism of production and its great value in distinguishing iron deficiency anemia from the anemia of chronic disease. PMID- 9372066 TI - Transgenic mouse models of sickle cell disease. AB - An array of sickle cell syndromes has been obtained in transgenic mice, expressing HbS or super HbS, from the asymptomatic phenotype similar to the human A/S state to a syndrome more severe than the human homozygous S/S state, inducing 100% fetal death. Anemia was observed in SAD and SAD (beta th/ beta +) neonates and disappeared during postnatal development. In adults, many features of sickle cell disease are found in transgenic mice, especially in SAD and SAD (beta th/ beta +) mice, including abnormal hemolysis, vasoocclusion, microthrombosis, infarct, priapism, chronic organ defects, and death on hypoxia. These mouse models are relevant to the study of the pathophysiology of sickle cell disease and the induction of vasoocclusion and to evaluate new therapeutic approaches in vivo. Clotrimazole and Mg2+ restore hydration of sickle cells and 12 C79 protected SAD mice from lethal acute hypoxia. PMID- 9372067 TI - Molecular basis of hypoxia-induced erythropoietin expression. AB - Erythropoietin gene (EPO) expression is activated by tissue hypoxia in renal peritubular interstitial fibroblasts and, to a lesser extent, in hepatocytes and ito cells of the liver. A hypoxia-inducible enhancer spanning approximately 50 bp within the 3'-flanking region of the EPO gene is required for transcriptional activation in hypoxic cells. Hypoxia-inducible factor 1 is a basic helix-loop helix protein that binds at the 5' end of the enhancer. The binding of hypoxia inducible factor 1 is absolutely required for enhancer function. Hepatocyte nuclear factor 4 is an orphan receptor that binds at the 3' end of the enhancer. The binding of hepatocyte nuclear factor 4 augments hypoxia-inducible transcription mediated by the enhancer but is not absolutely required for enhancer function. Factors binding to the enhancer may interact synergistically with factors binding to the EPO promoter to activate transcription in hypoxic cells. Indirect evidence suggests that oxygen tension may be sensed by a hemoprotein. In one model, the putative hemoprotein adopts different conformational states depending on whether O2 is bound. Another model proposes that the hemoprotein converts O2 to H2O2. The protein tyrosine kinase c-Src, GTP binding protein Ras, and MAP kinase signal pathways have been implicated in hypoxia signal transduction, but no direct evidence links these pathways to EPO transcriptional activation. PMID- 9372068 TI - Bone marrow transplantation for sickle cell anemia. AB - The use of bone marrow transplantation for hemoglobinopathies was first proposed in thalassemia major and is now the therapy of choice for young patients affected by this disorder and having a suitable donor. Even though bone marrow transplantation is very effective in treating sickle cell anemia, enthusiasm for it is restrained by the unpredictable course of the disease. Selection criteria are difficult to establish and vary among medical teams and their patients' characteristics. Some of the factors playing a role in the decision are summarized in this article. They include genetic and environmental factors, features of the patient such as age or the presence of organ damage, and the possibility of using new alternative therapeutic approaches. PMID- 9372070 TI - Erythrocytes. PMID- 9372069 TI - The molecular basis of the sideroblastic anemias. AB - The sideroblastic anemias display remarkable clinical and hematologic heterogeneity but share in common mitochondrial iron loading as evidence of unhinging between intracellular iron metabolism and heme biosynthesis. Molecular defects responsible for this unhinging have now been identified and appear to display matching heterogeneity. Mutations in the erythroid-specific ALA synthase 2 (ALAS2) gene cause microcytic anemia, whereas mitochondrial DNA deletions are responsible for Pearsons syndrome with a macrocytic anemia. The molecular basis for other causes including X-linked non-ALAS2-associated autosomal inheritance and for the more frequent acquired forms of this disorder awaits discovery. Speculation about their causes includes disturbed intracellular iron homeostasis involving iron-responsive factors involved in the translational control of ALAS2 and in certain nuclear and mitochondrial genes important for erythroid mitochondrial metabolism. PMID- 9372071 TI - Recent advances in understanding and clinical applications of the hematopoietic growth factors. PMID- 9372072 TI - Economic analysis of the clinical uses of the colony-stimulating factors. AB - Colony-stimulating factors can reduce the morbidity and possibly the mortality from some types of cancer treatment. Reductions in hospitalization and supportive care, eg, transfusion requirements and antibiotics, have been documented in several clinical trials and can lead to lower total care costs. However, the high cost of colony-stimulating factors and the necessity to treat large numbers of patients who do not benefit can offset the economic gains, unless the savings in hospitalization and supportive care are substantial. Primary prophylaxis with colony-stimulating factors is cost-saving only if the rate of hospitalization for febrile neutropenia is 40% or more; no current standard regimens are near that figure. In general, the American Society of Clinical Oncology clinical practice guide-lines for the use of colony-stimulating factors lead to effective and cost conscious use of these expensive growth factors. Colony-stimulating factors are not recommended for primary prophylaxis of febrile neutropenia, are recommended for secondary prophylaxis if dose-reduction is not appropriate, and are recommended for stimulation of hematopoietic progenitor cells and reconstitution after high-dose chemotherapy. Further expansion of use based on economic factors will depend on documented survival benefit, major improvements in supportive care due to colony-stimulating factors, or markedly lower costs of colony-stimulating factors. PMID- 9372073 TI - Advances in understanding the biology and function of the G-CSF receptor. AB - G-CSF is the major growth factor involved in the production of neutrophilic granulocytes. G-CSF exerts its function via the activation of a membrane receptor that belongs to the super-family of hematopoietin receptors, also referred to as class I cytokine receptors. In this review we summarize the current knowledge of the function of the G-CSF receptor in normal granulopoiesis, as well as in some patients with severe congenital neutropenia and acute myeloblastic leukemia, diseases characterized by disturbed myeloid maturation. PMID- 9372074 TI - Advances in understanding the postreceptor mechanisms of action of GM-CSF, G-CSF, and Steel factor. AB - Intracellular signaling events occurring downstream of receptor activation for the colony-stimulating factors GM-CSF and G-CSF and Steel factor the latter a member of the tyrosine kinase receptor family of hematopoietic growth factors, are discussed. Hematopoietic signaling pathways, including the Ras/Raf-1/MAP kinase cascade and the Jak-STAT pathway are defined and links existing between separate signaling pathways are discussed. Emphasis is given to exploring the relationships that exist between activation of receptor-associated proteins and signal transduction pathways, and the regulation of gene transcription, translation, and hematopoietic cell proliferation. A model system exploring the synergistic interaction between GM-CSF and Steel factor in the regulation of hematopoietic cell proliferation is presented. PMID- 9372075 TI - Cytokine regulation of apoptosis in hematopoietic precursor cells. AB - Cytokines are known to influence hematopoietic precursor cell survival. Apoptosis (a programmed cell death pathway) has been identified as the key factor limiting hematopoietic precursor cell survival and cytokines have been demonstrated to induce or prevent apoptosis in a variety of hematopoietic precursor cell populations. Whether a specific cytokine inhibits or suppresses apoptosis depends on cytokine-mediated modulation of target cell cytokine receptors, cell death regulator genes such as bcl-2 family members, Fas receptor, and other pathways. Finally, the intracellular pathways of cytokine receptor-mediated control of apoptosis have begun to be unraveled, implicating specific intracellular receptor domains and protein kinases in the regulation of apoptosis and hematopoietic precursor cell survival. PMID- 9372076 TI - Preclinical studies and potential clinical applications of c-mpl ligand. AB - The cloning of the gene for the endogenous c-mpl ligand, also known as thrombopoietin, was first reported less than 2 years ago. Recombinant mpl ligands based on this gene have been extensively evaluated in preclinical studies and are now in the early stages of clinical development. In vivo studies have confirmed that c-mpl ligand is a lineage-dominant cytokine and is the primary physiologic regulator of megakaryocytopoiesis. Recombinant mpl ligands can substantially reduce the severity and duration of thrombocytopenia due to myelosuppressive irradiation, chemotherapy, or both. Moreover, when recombinant mpl ligand is used in combination with r-metHuG-CSF, both thrombocytopenia and neutropenia can be prevented to the same degree as with either cytokine alone. In normal animals, the platelets produced in response to recombinant mpl ligand function appropriately and should not pose an undue risk for thrombosis when administered to thrombocytopenic patients. Initial clinical data confirm the safety and biologic activity of these new agents in humans. Clinical development will likely target the most myelosuppressive regimens, including those used in hematopoietic cell transplantation and acute myelocytic leukemia. Ultimately, the clinical benefit of these drugs will likely be judged on their ability to reduce the duration of severe thrombocytopenia and the need for platelet transfusions. PMID- 9372078 TI - Clinical development of recombinant human interleukin-11 to treat chemotherapy induced thrombocytopenia. AB - Recombinant human interleukin-11 stimulates megakaryocytopoiesis in vitro and platelet production in vivo. A clinical program to investigate the use of recombinant human interleukin-11 in patients with chemotherapy-induced thrombocytopenia began in 1992. These studies show the potential of recombinant human interleukin-11 as a treatment for chemotherapy-induced thrombocytopenia. The other activities of recombinant human interleukin-11, such as its ability to ameliorate mucositis in myelosuppressed animal models, may contribute to its clinical benefits in patients receiving chemotherapy. PMID- 9372077 TI - Current status of clinical development of interleukin-10. AB - Communication between cells in the lymphohematopoietic system is mediated by soluble molecules called cytokines. Lymphoid and myeloid cells are the cellular targets and source of these regulatory molecules. Interleukin-10 seems to be a main factor of a negative feedback system that inhibits synthesis of proinflammatory cytokines and of colony-stimulating factors in a variety of cells. Considering the cytokine synthesis-inhibiting action of interleukin-10 in activated macrophages, T cells, neutrophils, and eosinophils, many of the biologic effects of interleukin-10 may result in immunosuppression. Recently, the interleukin-10 receptor and some signal transduction events following interleukin 10 binding have been characterized. Substantial progress has also been made in providing the experimental basis for interleukin-10 therapy in various diseases. In vitro and preclinical studies suggest that interleukin-10 may prove quite useful in clinical settings in which overexpression of cytokines is likely to play an important role in pathogenesis, including inflammatory bowel disease, acute pancreatitis, septic shock, and certain malignancies. PMID- 9372079 TI - Potential clinical applications of interleukin-12. AB - Interleukin-12 is a central modulatory cytokine with potent effects on the development and differentiation of the cellular immune response. Because of its biologic activities, interleukin-12 could either mediate or contribute to the control of a large range of critical world-wide pathologic conditions, including infectious diseases and cancer. Its potential efficacy has been demonstrated in several animal models of intracellular pathogens and tumors, as well as in vitro in some human pathologies. As an adjuvant, interleukin-12 appears to be useful for inducing a protective immune response in different animal models. However, its potential toxicity and complex regulation indicate that clinical trials must proceed with caution. Thus its prophylactic and therapeutic value may reside in our ability to minimize toxicity and simultaneously deliver this cytokine to immunologically relevant sites. PMID- 9372080 TI - Clinical applications of stem cell factor. AB - Stem cell factor is an early-acting hematopoietic cytokine that probably functions constitutively to support the proliferation and survival of pluripotent progenitor cells and to increase their receptivity to lineage commitment and differentiation in response to lineage-specific cytokines. Stem cell factor also can induce proliferation and activation of mast cells. In vitro and in vivo, stem cell factor has demonstrated synergy with other hematopoietic cytokines. In clinical trials, stem cell factor has been shown to mobilize peripheral blood progenitor cells and when combined with G-CSF to increase the number of peripheral blood progenitor cells harvested. When used in lower doses and with antihistamine and beta-agonist premedication, stem cell factor therapy has been well tolerated. Phase III trials are in progress to document the efficacy of stem cell factor in peripheral blood progenitor cell harvesting protocols. Future clinical applications may include the treatment of adult and pediatric marrow failure states, the ex vivo expansion and manipulation of hematopoietic progenitor cells, and the treatment of disorders of skin pigmentation. PMID- 9372081 TI - Physiologic roles of interleukin-2, interleukin-4, and interleukin-7. AB - The use of gene targeting techniques has led to new insights into the physiologic function of lymphoid growth factors, their receptors, and associated signal transduction molecules in the formation and function of T and B cells. Mice rendered deficient for the growth factors interleukin-2 or interleukin-4 exhibit impairment in certain immune responses and in steady-state immune function, although production and expansion of lymphocyte populations is unaffected. In contrast, mice deficient for interleukin-7 show a severe lymphopenia in most lymphoid tissues. Interleukin-2, interleukin-4, and interleukin-7 all utilize the common gamma (gamma c) receptor component at the cell surface of lymphocytes and the Jak3 kinase molecule to transduce signals inside the cell. Both gamma c- and Jak3 kinase-deficient animals display a phenotype similar to interleukin-7 deficient animals in terms of lymphoid development. Collectively, these genetic experiments clearly define different in vivo roles for these lymphoid factors. Interleukin-2 and interleukin-4 function by influencing mature lymphocyte populations during immune responses, whereas interleukin-7 plays a singularly dominant role, in terms of the ligands that bind to the gamma c receptor, for the production and expansion of lymphocytes. PMID- 9372082 TI - Ex vivo expansion of hematopoietic precursor cells. AB - The availability of several newly described recombinant human hematopoietic growth factors has improved the technique of ex vivo expansion of CD34+ hematopoietic progenitor cells. Of particular interest are the strategies for the cytokine-mediated expansion of primitive progenitor cells. Moreover, various techniques have been proposed for the differential expansion of CD34+ progenitors toward selective hematopoietic lineages, including myeloid and megakaryocytic progenitors and post-progenitors. In addition, there are several approaches to selectively generate dendritic cells from CD34+ progenitor cells for potential clinical use. Finally, the first clinical applications of ex vivo generated progenitor cells to support hematopoiesis after high-dose chemotherapy were reported recently. This article briefly summarizes the recent technical developments as well as the first clinical trials with ex vivo expanded hematopoietic progenitors. PMID- 9372083 TI - Consensus on the clinical use of myeloid growth factors. AB - Myeloid growth factors have significantly improved the quality of life and reduced the morbidity of patients experiencing chemotherapy-induced neutropenia or undergoing bone marrow transplantation. However, in only a few instances have they directly contributed to improved response rates, better disease-free survival, or decreased mortality. With their increased use, concern has risen about their cost-effectiveness and appropriateness. To justify the use of myeloid growth factors and maximize patient benefit while minimizing the cost to health care systems and society, the development of guidelines for the clinical use of these expensive drugs is of great importance. In recent years both a European and an American expert panel have tried to establish consensus guidelines based on published evidence. A remarkable agreement can be found between results of both working parties. Clear recommendations for an optimal and more rational use of myeloid growth factors in clinical practice on both sides of the ocean have been delineated. PMID- 9372084 TI - Hematopoietic growth factors. PMID- 9372085 TI - Acute leukemia in children. AB - Advances in the molecular characterization of leukemic cells have greatly improved the precision of diagnosis and treatment assignment as well as the monitoring of residual disease in both acute lymphoblastic leukemia and acute myeloid leukemia. Currently, specific genetic rearrangements can be identified in as many as 50% of children with either acute lymphoblastic leukemia or acute myeloid leukemia. The genes p16 (or MTS1) and TEL/AML1 are now respectively recognized as the most common tumor suppressor and fusion genes in childhood acute lymphoblastic leukemia. Increasingly, contemporary protocols for the acute leukemias are relying on genetic information to guide treatment decisions. Examples include the use of allogeneic hematopoietic stem cell transplantation for acute lymphoblastic leukemia with the BCR-ABL fusion gene or MLL rearrangement, and for acute myeloid leukemia with monosomy 7; antimetabolite based therapy for acute lymphoblastic leukemia cases with hyperdiploidy of more than 50 chromosomes (DNA index > or = 1.16); and retinoic acid and anthracycline containing regimens for the acute promyelocytic acute myeloid leukemia subtype with PML-RARA fusion. Other efforts are being made to reduce the long-term sequelae of treatment. Indeed, extended intrathecal therapy and intensive systemic chemotherapy will, in all likelihood, replace cranial irradiation as subclinical central nervous system therapy for patients with intermediate-risk acute lymphoblastic leukemia, and perhaps even for those with high-risk acute lymphoblastic leukemia. The challenge now is to identify specific treatments for other genetically defined subtypes of leukemia. This goal will be realized only through protocol-based studies employing uniform criteria for defining risk status. PMID- 9372086 TI - Acute leukemia in adults. AB - Several trends are emerging in the treatment and investigation of acute leukemia in adults; in this review both of these aspects are addressed. Chemotherapy forms the mainstay of treatment for acute myeloblastic leukemia. In the past year, groups reported on the value of dose intensification in patients with acute myeloblastic leukemia under the age of 60 years and on the role of intensive chemotherapy combined with growth factors in the treatment of elderly patients. Similarly, the role of autologous bone marrow transplantation for older patients has been studied. Improvements in the treatment of patients with acute leukemia are likely to come from a recognition and understanding of the biologic attributes of the leukemic cell. Failure to cure leukemia is likely due to failure to eradicate the leukemic clone. Mechanisms of drug resistance acting before the drug reaches its target (proximal resistance) and after the drug interacts with its target (distal resistance) are gaining greater importance in understanding treatment failures. Advances have been made in identifying new mechanisms that are involved in proximal as well as distal drug resistance. Genetic changes both at the cytogenetic and the molecular level identify different FAB subgroups and groups of patients with good and bad prognostic features. Finally, reports are reviewed of two new factors that stimulate the growth of acute myeloblastic leukemia cells (thrombopoietin and Flt3 ligand) and a factor that inhibits the autocrine growth characteristics of acute myeloblastic leukemia cells (interleukin-10). The results of these interface and basic studies offer the hope of identifying groups of patients with different therapeutic needs and suggest ways to develop therapies aimed at the biology of the leukemic cell. PMID- 9372087 TI - Non-Hodgkin's lymphoma. AB - Attention is being directed at increasing the intensity of therapy as a means of improving the results of primary therapy for non-Hodgkin's lymphoma. There is increasing evidence that the use of high-dose consolidation therapy followed by autologous hematopoietic rescue in first remission improves survival in high-risk patients. There is also evidence from randomized trials that transplantation for relapsed patients improves survival compared with conventional salvage chemotherapy. Phase II trials of radiolabeled antibody therapy are providing promising results. There is still no definitive evidence that any treatment of advanced low-grade lymphoma prolongs survival, although the use of allogeneic bone marrow transplantation is under investigation. Treatment designed to eradicate Helicobacter pylori can cause regression in approximately 50% of patients with gastric lymphomas of mucosa-associated lymphoid tissue, although long-term follow-up information is lacking. The results of treatment for mantle cell lymphoma are poor and there is no consensus on management. Most trials of primary central nervous system lymphoma are employing systemic chemotherapy with drugs that penetrate the blood-brain barrier in addition to radiation. PMID- 9372088 TI - Recent advances in Hodgkin's disease. AB - Most patients who present with Hodgkin's disease today can be cured of their disease. Current treatments strive to maintain a high level of efficacy while reducing the chance of long-term side effects that limit the quality and length of survival. Epidemiologic and sophisticated molecular techniques continue to add to our understanding of the etiology and pathogenesis of this disease. However, the heterogeneity and paucity of "malignant" cells in Hodgkin's disease continue to limit our ability to articulate a coherent and encompassing model of this disease. PMID- 9372089 TI - Tumor cell survival and resistance to therapy. AB - The primary reason for the failure to cure patients with cancer remains the development of multiple mechanisms of resistance to cytotoxic agents. The two major effectors of tumor cell killing include genotoxic agents and cell-mediated immunity. Genotoxic agents function primarily by initiating pathways leading to apoptosis or programmed cell death, whereas immune-mediate cytotoxicity utilizes both programmed cell death-promoting as well as cytolytic processes. The mechanisms leading to treatment resistance initially involve alterations in the way tumor cells transport, metabolize, and provide substrates for cytotoxic agents. Beyond these specific mechanisms, tumor cells may also express alterations in the regulators and effectors of apoptotic death, thus creating a more generalized resistance pattern. Through a variety of other mechanisms, tumor cells may also decrease specific antigen expression or the ability to costimulate T lymphocytes. The result of antigen recognition in the absence of costimulation can lead to antigen-specific tolerance, which may also represent a major form of escape from immune-mediated killing. The elucidation of these mechanisms of resistance to therapy and tumor cell survival should form the basis for the development of more effective therapies. PMID- 9372090 TI - Multiple myeloma and chronic lymphocytic leukemia. AB - Much progress has been made in delineating the pathogenesis of multiple myeloma and chronic lymphocytic leukemia. The cell of origin in both diseases has been better defined, which has led to important clinical treatments. For myeloma, reduction of tumor burden in autografts has been accomplished and been associated with favorable outcome. The importance of interleukin-6 in maintaining this tumor and causing skeletal disease has been more clearly defined and has led to treatment with antibodies that block this cytokine's action. The bisphosphonate pamidronate decreases skeletal complications and improves quality of life for these patients. For chronic lymphocytic leukemia, further definition of common cytogenetic and gene abnormalities have been made and associated with patient outcome. The nucleoside analogues continue to produce excellent responses and the use of myeloablative chemotherapy with hematopoietic support shows promise in early studies. PMID- 9372091 TI - Myelodysplastic syndrome. AB - Myelodysplasia is being increasingly recognized as an important disease not only in the elderly but also in younger patients. It is also being seen more commonly as a complication of treatment with chemotherapeutic agents. Recent advances have distinguished between the different forms of therapy-related myelodysplasia as well as their genetic associations. Although allogeneic bone marrow transplantation using either related or unrelated donors offers the only chance for cure of this disease, cell biology studies also indicate that there is a normal stem cell compartment in the bone marrow of patients with myelodysplasia. Future studies may offer the opportunity for autologous stem cell transplantation for patients achieving remission after induction chemotherapy. PMID- 9372092 TI - Chronic myelogenous leukemia. AB - Chronic myelogenous leukemia involves clonal expansion of hematopoietic progenitor cells associated with the characteristic translocation between chromosomes 9 and 22, resulting in the generation of an aberrant bcr-abl protein with enhanced tyrosine kinase activity. The bcr-abl protein can induce cell proliferation, induce transformation of immature hematopoietic cells, and suppress apoptosis in vitro. Abnormalities of stromal cell and progenitor cell interaction may be central to the pathogenesis of the abnormal hematopoiesis in chronic myelogenous leukemia. Therapy with interferon alpha in chronic-phase chronic myelogenous leukemia can result in hematologic responses in up to 70% to 80% of patients and partial or complete cytogenetic responses in up to 50%; many studies show a significant overall survival advantage for patients treated with interferon. Allogeneic marrow transplantation can result in long-term survival for patients with chronic myelogenous leukemia, particularly younger patients undergoing transplantation early in the course of disease, and unrelated donor or autologous marrow transplantation may be an option for patients without a matched sibling donor. Future therapy will likely involve selection and expansion ex vivo of Ph- stem cells for reinfusion as part of a strategy for autologous marrow transplantation. Other areas of current investigation include in vitro assessment of the activity of antisense oligonucleotides and of the immunologic responses to chronic myelogenous leukemia cells. PMID- 9372093 TI - Detection of minimal residual disease in acute and chronic leukemias. AB - The study of minimal residual disease is an attempt to redefine the concept of remission. Opinion as to the clinical utility of minimal residual disease is still in evolution. It has become clear that the ability to merely detect minimal residual disease by the polymerase chain reaction amplification of the molecular "fingerprint" of a leukemia does not always foretell relapse. Rather, careful consideration must be taken of the context of the type of disease, the molecular lesion itself, and the type of therapy employed. Thus although the detection of minimal residual disease in acute lymphoblastic leukemia or acute promyelocytic leukemia has a high correlation with relapse, detection of minimal residual disease in t(8;21) acute myelogenous leukemia has little correlation with relapse. In some diseases (eg. chronic myeloid leukemia) the clinical relevance of minimal residual disease detection may be strengthened by quantification, although this in itself introduces another level of complexity and potential pitfalls. Nevertheless, we are moving toward the day when the molecular definition of disease status will guide therapy. PMID- 9372094 TI - Deregulation of cell cycle control in hematologic malignancies. AB - Cell cycle progression is governed by a complex network of positive and negative regulatory molecules. Mutations in cell cycle regulatory proteins occur frequently in tumor cells and defective cell cycle control is a common and perhaps universal feature of malignant transformation. This review outlines current models of normal cell cycle progression, focusing on the G1 phase of the cell cycle, and describes specific mutations that have been discovered in leukemias and lymphomas. PMID- 9372095 TI - Hematopoietic cell proliferation and differentiation. AB - The use of colony-stimulating factors to stimulate hematopoietic cell proliferation and differentiation in vivo is under still increasing investigation, particularly in the field of stem cell transplantation. This review discusses recently published results and tries to extrapolate lines of future development from the achievements reached to date. PMID- 9372096 TI - Prognostic markers in acute leukemia. AB - The identification of biologic markers for disease outcome in hematopoietic malignancies is essential for the development of "risk-adapted" therapies. Although new prognostic factors are frequently described, their real clinical and biologic impact is often difficult to determine. Factors that influence a marker's true prognostic value include several variables of study design: study size, uniform versus nonuniform patient treatment, methodologic variations, and correlations with other variables. Despite these concerns, several important prognostic factors have emerged in acute leukemias. For example, in acute myeloid leukemia, the multidrug resistant phenotype, whether conferred by the classic P glycoprotein (multidrug resistance protein 1) or by other mechanisms, and cytogenetics are major prognostic indicators for outcome. In acute lymphoblastic leukemia, markers associated with loss of growth control (loss of tumor suppressor genes, increased proliferative fraction) likewise identify a group of poor-prognosis patients. The delineation of prognostic factors such as these allows for the better identification of patients who may benefit from risk adapted therapies. PMID- 9372097 TI - Hematologic malignancies. PMID- 9372098 TI - Diagnosis, clinical course, and management of idiopathic thrombocytopenic purpura. AB - Idiopathic thrombocytopenic purpura is a common acquired bleeding disorder. However, the diagnosis is often uncertain because there are no specific tests that define idiopathic thrombocytopenic purpura, and management decisions are often difficult because there are no firm data to define the clinical course and to estimate the risks of major bleeding and death. Because the incidence of idiopathic thrombocytopenic purpura is greatest in young women, its occurrence during pregnancy is a frequent problem, with specific issues related to the anticipated route of delivery and the risks for neonatal thrombocytopenia. To address these unresolved issues, the American Society of Hematology established a panel to develop a practice guideline for idiopathic thrombocytopenic purpura. The data from this recently published document and its recommendations are summarized in this review. PMID- 9372099 TI - Management of thrombocythemia. AB - The pathogenesis of essential thrombocythemia as a clonal myeloproliferative disorder has been clearly established. However, there continues to be considerable controversy concerning the management of this disease, particularly because its natural history is consistent with a nearly normal life expectancy. Therapeutic decisions have been complicated by a reliance on largely anecdotal, retrospective experience in the medical literature and, until very recently, an absence of prospective, controlled clinical trials. A recent study of patients with essential thrombocythemia at high risk of thrombosis because of advanced age or previous history of thrombotic complications demonstrated that platelet cytoreduction with hydroxyurea is effective in reducing thrombotic complications. Other cytoreducing agents that have been used in this disease include alkylating agents, recombinant interferon alpha, and anagrelide. The use of antiplatelet therapy is also controversial, and is most highly effective in patients with digital or cerebrovascular ischemic problems. PMID- 9372100 TI - Platelet transfusion support for patients with cancer and hematologic malignancies. AB - Advances in platelet transfusion have contributed to improved outcomes in the treatment of patients with cancer and leukemia. However, the optimal strategies to avoid some of the side effects that could result from platelet transfusions remain under investigation. These side effects include the development of refractoriness to transfusions, alloimmunization, transfusion reactions, the transmission of infectious agents, and transfusion-associated graft-versus-host disease. Leukodepletion by filtration is promising as a means of preventing the development of alloimmunization. Results of the Trial to Reduce Alloimmunization to Platelets will be reported shortly and will shed more light on that issue. Bedside filtration of cellular blood products also diminishes the transmission of cytomegalovirus infections by that route. Transfusion reactions are often mediated by cytokines in the plasma fraction of transfused platelet concentrates, and leukodepletion prior to storage reduces their incidence. Serious bacterial infections are sometimes transmitted by platelet transfusions and improved methods are needed for their detection and prevention. Photochemical methods that could inactivate bacteria and viruses in contaminated products deserve further study. PMID- 9372101 TI - Aspirin therapy for cardiovascular disease. AB - Aspirin is a widely used and effective antithrombotic agent. Recent studies suggest that aspirin's anti-inflammatory effects are mediated via inhibition of an inducible isoform of cyclooxygenase in inflammatory cells (COX-2) and through blockade of the nuclear transcription factor, NF-kappa B. The optimal dose of aspirin for most clinical situations is 75 to 325 mg/d, but debate continues as to whether higher doses are needed to prevent cerebral ischemia. Aspirin is very effective for inhibition of platelet-mediated thrombosis at sites of vascular injury but does not reduce restenosis after coronary angioplasty or carotid endarterectomy, nor does it prevent a first stroke. Combined therapy with warfarin and aspirin has been shown to limit systemic embolic in high-risk patients with artificial heart valves, but at the cost of increased bleeding. A new aspirin derivative is currently being developed that appears to stimulate platelet nitric oxide release, inhibit thrombin-induced platelet aggregation, and lower gastric toxicity. PMID- 9372102 TI - Oral anticoagulant therapy. AB - Oral anticoagulant therapy is effective antithrombotic treatment for several indications. The results of prothrombin time monitoring should be reported as the International Normalized Ratio (INR). An INR of 2 to 3 is the recommended therapeutic range for all indications except for the prevention of systemic embolism in patients with mechanical heart valves and for the long-term treatment of patients with myocardial infarction, for whom an INR range of 2.5 to 3.5 is recommended. Oral anticoagulant therapy with warfarin sodium is the preferred approach for preventing stroke in most patients with atrial fibrillation. The available data suggest that warfarin is more effective than aspirin. Aspirin, 325 mg/d, is indicated for patients in whom warfarin is contraindicated or in patients less than 75 years of age who are at low risk for stroke because risk factors are absent. In patients 75 years of age or more, close monitoring of warfarin treatment is prudent to avoid major bleeding due to poor anticoagulant control. In selected patients, patient-self-monitoring and adjustment of warfarin treatment using a portable prothrombin time monitor may be effective and safe. PMID- 9372103 TI - Laboratory testing for hypercoagulable disorders. AB - Evaluation of inherited hypercoagulability in patients with venous thromboembolism includes testing for the functional activity of protein S, protein C, antithrombin III, and for resistance to activated protein C. Resistance to activated protein C can be assessed with plasma as well as with DNA based assays that are commercially available. Acquired disorders include the development of antibodies against phospholipid-protein complexes (as would occur in patients with the antiphospholipid syndrome). The inherited and acquired abnormalities are most commonly apparent as superficial or deep venous thromboembolism in younger patients, most of whom have additional risk factors for thrombosis, such as use of oral contraceptives or recent trauma. These tests are cost effective if the results will influence patient management or will have potential value in the care of family members in situations of increased thrombotic risk. PMID- 9372104 TI - Plasminogen activator inhibitor 1 in thrombotic disease. AB - Impaired fibrinolytic function, mainly due to an elevation of plasma plasminogen activator inhibitor 1 concentration, is a common finding in patients with thrombotic disease. In patients subjected to hip surgery, preoperatively increased levels of plasminogen activator inhibitor 1 seem to be predictive of postoperative deep venous thrombosis. Several prospective studies of patients with angina pectoris or a past myocardial infarction have shown strong correlation between plasmatic plasminogen activator inhibitor 1 elevation and future cardiovascular events. However, before plasminogen activator inhibitor 1 can be regarded as a risk factor in the conventional epidemiologic sense, its relationship to myocardial infarction must be demonstrated in prospective studies of healthy populations. The regulation of plasminogen activator inhibitor 1 concentration in plasma is complex and at present not well understood. Multiple interactions with disturbances of both carbohydrate and lipoprotein metabolism are evident. Studies performed in cultured cells, transformed or natural, can be translated into human pathophysiology only with great caution. Both environmental and genetic factors seem to be of importance for the plasma plasminogen activator inhibitor 1 concentration. Platelet plasminogen activator inhibitor 1 seems to play a role in the resistance of platelet-rich thrombi to thrombolytic treatment. PMID- 9372106 TI - Gene therapy for the hemophilias. AB - This review discusses the progress of gene therapy for the hemophilias. The development of gene therapy for hemophilia A has been more problematic than that for hemophilia B. It is now well established that reduced expression of the human clotting factor VIII cDNA is caused by transcriptional repression. Multiple sequences within the factor VIII cDNA are involved. So far, attempts to improve the factor VIII cDNA expression have been unsuccessful. However, improved retroviral vectors and adenovirus-based vectors have been constructed that increase factor VIII expression. The use of these vectors has resulted in clinically relevant levels of human factor VIII in mice and hemophilic dogs. Thus, gene therapy for hemophilia A has reached the same developmental stage as that for hemophilia B. If further improvements can increase the persistence of expression and decrease the immunologic responses, phase I clinical trials in human individuals can be considered. PMID- 9372105 TI - Tissue factor in cancer angiogenesis and metastasis. AB - Tumor cells frequently express tissue factor, a transmembrane glycoprotein that functions as the cellular receptor and catalytic cofactor for the serine protease factor VIIa. In human tumors, tissue factor expression correlates spatially with neovascularization, indicating that tissue factor function may be linked to angiogenic properties of malignant tumors. Tissue factor also supports hematogenous tumor dissemination. The role of tissue factor in metastasis appears to involve both the coagulation pathway triggered by interactions of the tissue factor extracellular domain as well as cellular events dependent on the short cytoplasmic domain that may participate in tissue factor-mediated outside-in signaling. PMID- 9372107 TI - Thrombin-dependent inhibition of fibrinolysis. AB - Thrombin generation during coagulation affects the fibrinolysis resistance of clots. This phenomenon is mediated at least in part by a plasma carboxypeptidase that has been called carboxypeptidase-U, carboxypeptidase-R, pro-carboxypeptidase B, and thrombin-activatable fibrinolysis inhibitor. Carboxypeptidase-U circulates as an inactive proenzyme and is activated by thrombin in a process that is dramatically enhanced by the cofactor thrombomodulin. Clots formed in hemophilic plasma in the presence of a plasminogen activator lyse prematurely and this defect can be correlated by the addition of the missing coagulation factor or thrombomodulin. Thrombin-dependent inhibition of fibrinolysis, which is demonstrable in artificial systems in vitro, may help explain certain in vivo observations, including the delayed bleeding often seen in individuals with hemophilia. PMID- 9372108 TI - Fibrin sealant. AB - Fibrin sealant consists of fibrinogen and thrombin solutions, which generate a crosslinked fibrin clot in a process that mimics the last stage of the physiologic coagulation system. Fibrin sealants have been used widely in Europe in the past two decades for hemostasis, sealing, and as a vehicle for drugs and growth factors, and as a biologic glue. This review discusses the various types of fibrin sealants (autologous, homologous, commercial), their composition, mechanism of action, functional characteristics, experimental and clinical uses, limitations, complications, adverse reactions, and viral safety. PMID- 9372109 TI - Hemostasis and thrombosis. PMID- 9372110 TI - Human stem cell assays in immune-deficient mice. AB - Much of our understanding of the organization of the cells that comprise the hematopoietic system and the cellular and molecular mechanisms that regulate their development is derived from mouse models. However, knowledge of the human hematopoietic system and identification of human stem cells have, until recently, been hampered by the absence of in vivo assays that measure their repopulation capacity. The development of methods to transplant normal and leukemic human hematopoietic cells into immune-deficient SCID mice provides the foundation for human stem cell assays. This review will focus on recent evidence that normal and leukemic human stem cells can be assayed in these systems. PMID- 9372111 TI - Preclinical large animal models for hematopoietic stem cell transplantation. AB - The use of large animal models for marrow and stem cell transplantation has become increasingly important. Large animal models have recently been used for studying the principles of hematopoiesis and illustrate the relative slow rate of stem cell turnover compared with mice. Furthermore, large animals are used to study the effectiveness of varying conditioning regimens, as well as the influence of growth factors and various immunosuppressive agents such as corticotropin-releasing factor and mycophenolate mofetil on graft-versus-host disease and graft rejection. Large animal models have become useful in studying the combination of hematopoietic stem cell and solid organ transplants for the establishment of long-term tolerance in major histocompatibility complex mismatched settings. PMID- 9372112 TI - HLA matching in unrelated donor bone marrow transplantation. AB - The availability of an HLA-matched sibling donor in only 30% to 35% of patients requiring allogeneic bone marrow transplantation (BMT) has led to the proposal of unrelated donors as an alternative source of bone marrow. The greater HLA incompatibility, which, although present, was undetected until recently in many unrelated donor BMT cases, has resulted in a higher rate of posttransplant complications and impaired acturial survival when compared with HLA-matched sibling BMT. Molecular HLA typing enables us to evaluate the impact of incompatibility at each locus in the outcome of unrelated donor BMT. The overall retrospective data would recommend that HLA-A, -B and -C allelic molecular matching should be implemented in addition to HLA-DR allelic matching. Further retrospective analysis is needed in order to assess which incompatibility or combinations are better tolerated than others. Only the definitive knowledge at the sequence level of the donor and the recipient HLA allelic diversity involved in controlling the allogeneic immune response will allow us to understand the precise biologic rationale of the graft-versus-host disease. Knowledge and control of the HLA incompatibilities should allow us to offset the detrimental effects of histoincompatibility while developing strategies to take advantage of the beneficial graft-versus-leukemia effect. Also the role of minor histocompatibility antigens remains largely unknown and will require careful evaluation before minor antigens can be used as a selection criterion in BMT. Carefully designed prospective studies will enable us to test the impact of each HLA locus. HLA typing and BMT represent a successful example of productive cooperation between basic and clinical sciences that should be pursued for the improvement of the clinical outcome of unrelated donor BMT. PMID- 9372113 TI - The graft-versus-leukemia effect. AB - Although the graft-versus-leukemia effect was predicted from animal experiments almost 40 years ago, only recently has its role in clinical bone marrow transplantation become better defined. The graft-versus-leukemia effect was initially considered to be a minor component of the graft-versus-host reaction. However, more recent analyses of clinical bone marrow transplants and the successful treatment of relapsed leukemia with donor lymphocyte transfusions indicate that the graft-versus-leukemia effect can be very powerful and to some degree independent of graft-versus-host disease. Results of donor lymphocyte transfusions draw attention to wide variability in response according to the nature of the relapsed leukemia and also to additional therapies that may enhance the efficacy of donor lymphocyte transfusions. Although natural killer lymphocytes may play a role in the graft-versus-leukemia effect, attention is focusing increasingly on T lymphocytes as potent mediators of the effect. Both CD4+ and CD8+ cells, together with the cytokines they produce, can interact with leukemia cells to deliver a cytotoxic hit on the malignant clone. Although leukemia cells undoubtedly share common antigens with other tissues of the recipient resulting in nonspecific graft-versus-host and graft-versus-leukemia reactions, there is also the possibility that distinct antigens are presented to T cells by the leukemia cells, providing a basis for separating the graft-versus leukemia from graft-versus-host reactions. The current clinical challenge is to devise strategies for separating the graft-versus-leukemia response from graft versus-host disease. PMID- 9372114 TI - Gene marking and gene therapy directed at primary hematopoietic cells. AB - The past year has been a very active one in the field of gene transfer to hematopoietic targets, specifically stem cells and T cells. A number of clinical trials were published that both demonstrated progress as well as identified problems that investigators will face in trying to make the technology therapeutically applicable. Important laboratory and animal experiments focused on predictive models for human stem cell behavior, methods for culturing and expanding primitive cells ex vivo, immune responses against transgenes, in vitro and in vivo selection of transduced cells, and alternatives to standard retroviral vectors. PMID- 9372116 TI - High-dose therapy in multiple myeloma. AB - Autologous transplantation in myeloma can prolong survival as compared with standard chemotherapy but cannot be considered curative, as the majority of patients relapse within 5 years. Contaminating myeloma cells can be detected in stem cell harvests in the majority of patients, and the possibility that these cells lead to relapse has prompted widespread current interest in the use of positive stem cell selection as a means of purging. Allogeneic bone marrow transplantation is associated with a high transplant-related mortality but a lower relapse risk. A graft-versus-myeloma effect has recently been proven by the demonstration of response to donor lymphocyte infusion in patients relapsing after allogeneic bone marrow transplantation. PMID- 9372115 TI - The role of radioimmunotherapy in bone marrow transplantation. AB - Radioimmunotherapy offers an exciting new therapeutic modality for patients with recurrent hematologic malignancies and solid tumors resistant to conventional chemotherapy. In this review, a brief overview of tumor radiobiology as well as various obstacles to treatment is presented. Early radiolabeled antibody trials documented myelosuppression as the dose-limiting toxicity. Ongoing trials in solid tumors and hematologic malignancies are testing the hypothesis that myeloablative doses of radiation in conjunction with hematopoietic stem cell rescue will improve long-term survival. For solid tumors, there are many barriers to achieving this goal. The most encouraging trials in metastatic breast cancer have documented significant symptomatic relief and a 50% partial response in patients. In contrast, trials involving hematologic malignancies have produced more impressive results. With a median follow-up of 33 months, 67% of patients with recurrent acute myelogenous leukemia or myelodysplasia treated with radiolabeled antibodies, total-body irradiation, and high-dose chemotherapy remain disease free. Alone, myeloablative doses of radioimmunotherapy have documented a 41% complete response in patients with Hodgkin's disease. Seattle trials with recurrent non-Hodgkin's lymphoma have demonstrated objective responses in 90% of patients, complete responses in 85% of patients, a progression-free survival of 62%, and an overall survival of 93% with a median follow-up of 2 years. PMID- 9372117 TI - Severe aplastic anemia including Fanconi's anemia and dyskeratosis congenita. AB - The primary pathophysiology in the majority of cases of acquired aplastic anemia remains unknown ("idiopathic"). In contrast, there have been major advances in Fanconi's anemia, the commonest of the familial aplastic anemias. The key has been complementation analysis that provides evidence for at least five complementation groups (FA-A, FA-B, FA-C, FA-D, and FA-E) and therefore five genes for Fanconi's anemia; only the FAC gene has been cloned to date. The FAC gene has an important role in normal hematopoiesis, and expression of the mutant FAC allele is associated with increased apoptosis. Increased apoptosis is also seen in patients with idiopathic aplastic anemia. Furthermore, patients with Fanconi's anemia or dyskeratosis congenita, another familial form of aplastic anemia, have a high incidence of hematopoietic clonal disorders, as do patients with idiopathic aplastic anemia. Therefore, the familial aplastic anemias are good in vivo models for studying aplastic anemia in general; some of the idiopathic aplastic anemias could prove to be due to mutations in genes characterized originally in familial aplastic anemias. Thus identification of these genes may provide insights into the pathophysiology of idiopathic aplastic anemia and suggest new treatment options, because treatment remains unsatisfactory for patients who lack HLA-identical siblings who can serve as bone marrow donors. The recent mapping of the FA-A (16q24.3), FA-D (3p22-26), and dyskeratosis congenita (Xq28) genes suggests this goal is achievable. PMID- 9372118 TI - Immunologic reconstitution following stem cell transplantation. AB - The efficacy of bone marrow transplantation is contingent on not only the eradication of malignancy and restoration of hematopoiesis, but also successful reconstitution of the immune system. Opportunistic infections, despite resolution of neutropenia, continue to be the major cause of nonrelapse mortality following HLA-matched sibling transplants and are often the main cause of overall mortality following unrelated marrow transplantation. In two unrelated transplant series published within the past year fatal viral, fungal, and/or parasitic infections accounted for 16% and 34% of the mortality observed in children and adults, respectively, following unrelated bone marrow transplantation. Unfortunately, mortality secondary to infection has not changed significantly following unrelated bone marrow transplantation over the past 5 years. T- and B-cell deficits after transplantation have been well recognized. During the past year, not only have additional defects been elucidated, but two successful strategies to overcome them, namely adoptive immunotherapy to restore cytomegalovirus and Epstein-Barr virus cellular immunity, have been reported. PMID- 9372119 TI - Secondary malignancies. AB - Malignant diseases are of particular concern as increasing numbers of patients survive the early phase after transplantation and remain free of their original disease. This article summarizes recent articles published on this topic, with particular emphasis on those published during the past 12-month review period. These recent clinical and biologic data on secondary malignancies (leukemia, lymphoma, and solid tumors) occurring after either allogeneic or autologous stem cell transplantation are summarized in this review. PMID- 9372120 TI - Biologic functions of blood group antigens. AB - In the past few years, we have learned a great deal about the biologic function of structures bearing blood group antigens. Some blood group antigen-bearing proteins function as major transport channels within the erythrocyte membrane; these include the anion transporter (band 3: Diego and Wright antigens), the water channel (aquaporin: Colton antigens), and the urea transporter (Kidd antigens). At least two erythrocyte blood group antigen proteins have complement regulatory functions: the complement receptor type 1 (CR1, CD35: Knops antigens) and decay accelerating factor (DAF, CD55: Cromer antigens). Some blood group antigens reside on proteins with known receptor functions, such as the chemokine receptor (Duffy) and the hyaluronan receptor (Indian). The Cartwright antigens reside on an enzyme, acetylcholinesterase, and the Kell antigens reside on a protein that belongs to the CALLA-related family of neutral metalloproteinases. Finally, some blood group antigens reside on proteins that serve crucial structural functions necessary to normal erythrocyte lifespan and morphology. These proteins include band 3, glycophorins C/D (bearing the Gerbich antigens), and the Rh proteins. Both oligosaccharide and protein blood group antigens may act as receptors for bacterial, viral, and parasitic infectious agents. PMID- 9372121 TI - Prenatal testing to predict the severity of hemolytic disease of the fetus and newborn. AB - The severity of hemolytic disease of the fetus or newborn can be assessed with certainty only by measurement of fetal parameters. However, these invasive procedures are not without risk for the fetus. Most erythrocyte antibodies do not cause significant hemolytic disease of the fetus or newborn and various assays are available to assist obstetricians in predicting the likely effect of maternal alloantibodies on fetal erythrocytes. Initially, immunohematologic tests are performed on maternal serum to identify antibodies with a potential for causing hemolytic disease of the fetus or newborn. Antibody concentration is measured by indirect antiglobulin technique titration, or where possible (for anti-D or -c), by quantitation. When used consecutively throughout pregnancy, these tests will reveal a trend that helps to predict the likelihood of hemolytic disease of the fetus or newborn. Functional assays (antibody-dependent cell-mediated cytotoxicity and chemiluminescence) are probably superior to serologic tests for predicting hemolytic disease of the fetus or newborn. Unfortunately, the assays do not reflect accurately the in vivo conditions for a given patient. Knowledge of the immunoglobulin subclass can help to assess the hemolytic potential of maternal antibody, but quantitative measurement of subclasses is still experimental. Diagnostic testing should be approached in a structured manner, commencing with simple serology, followed, in selected cases, by more complex functional assays and indirect fetal tests to identify those fetuses at greatest risk. This approach will enable direct fetal tests to be undertaken only when there is strong suspicion of severe hemolytic disease of the fetus or newborn. PMID- 9372122 TI - Blood transfusion in sickle cell disease. AB - Blood transfusion can be life saving in sickle cell disease, both in emergencies and to prevent organ damage. Practice has developed through anecdote and experience so that patients are probably overexposed to transfusions in the developed world, whereas the majority of patients who live in the underdeveloped world do not have access to transfusion and those who do are exposed to unsafe practices. The role of transfusion medicine in sickle cell disease is also increasing with the development of bone marrow and solid organ transplant programs and placental stem cell banking. The modes and roles of transfusion in sickle cell disease as well as pharmacologic therapies are discussed. Multicenter, collaborative, randomized trials need to be developed, over the next few years, to study all aspects of transfusion in sickle cell disease. PMID- 9372123 TI - Alternative oxygen carriers. AB - Alternative oxygen carriers are being evaluated in human studies. Information from the clinical evaluation of these "blood substitutes" is not publicly available. Preclinical studies of solutions of modified cell-free hemoglobin and of perfluorocarbon emulsions have demonstrated significant toxicity. Hemoglobin inactivates endothelium-derived nitric oxide, participates in free-radical reactions, is a neurotoxin, activates the immune system, potentiates the effects of bacterial endotoxin, and increases the lethality of certain bacterial infections. Perfluorocarbon emulsions activate complement and cause lung dysfunction. Both materials have short intravascular half-lives. Safe doses of perfluorocarbon emulsions have very limited oxygen-carrying capacity. Protein engineering to reduce the toxicities of the modified hemoglobins is ongoing. A safe and effective erythrocyte substitute is still a distant goal. PMID- 9372124 TI - Intravenous anti-D immunoglobulin in the management of immune thrombocytopenic purpura. AB - Approximately 70% to 80% of Rh-positive adults and children with acute or chronic immune thrombocytopenic purpura or HIV-related thrombocytopenia respond to infusions of anti-D immunoglobulin. The speed of onset of response is slower than that seen with intravenous immunoglobulin. Anti-D immunoglobulin is well tolerated, with occasional adverse reactions similar to those seen in treatment with polyclonal intravenous immunoglobulin, but anemia requiring blood transfusion can occur. Response is generally better in younger patients and those who have responded to other forms of treatment. Inhibition of Fc receptor mediated platelet destruction by anti-D immunoglobulin-opsonized erythrocytes is the most likely mechanism of action, although the relative ineffectiveness of a monoclonal anti-D immunoglobulin preparation in treatment of immune thrombocytopenic purpura suggests that other mechanisms may exist. Hepatitis C has been transmitted by intravenous anti-D immunoglobulin preparations when used in the prevention of Rh immunization, prior to the introduction of screening donor plasma for hepatitis C virus antibodies. However, an intravenous solvent detergent-treated preparation is now available. PMID- 9372126 TI - Hematopoietic stem cell transplantation. PMID- 9372125 TI - Therapeutic plasmapheresis. AB - Considerable work has been carried out over the past 25 years to define the conditions for application of plasmapheresis or plasma exchange. The use of plasma exchange in neurologic disorders such as Guillain-Barre syndrome has seen widespread application including the combination of plasma exchange with the use of intravenous immunoglobulin. Investigators have assessed the use of each therapy alone and in combination and, although both are advantageous, the relative benefits of each are still somewhat unclear. Other forms of neuropathies also seem to benefit from plasma exchange, as do some vasculitides. The use of cryosupernatant rather than frozen plasma to treat thrombotic thrombocytopenic purpura has improved outcome, but the cumulative data from many trials indicate that the mortality rate, if anything, persists at an even higher level than it did decades ago. Hemolysis, elevated liver enzymes, and low platelets syndrome, which has some characteristics similar to those of thrombotic thrombocytopenic purpura, has been shown to have variable response to plasma exchange. Plasma exchange has also been assessed as a treatment in organ failure and transplant rejection. Liver failure has shown variable response even when bioartificial livers are used. Of particular interest is the emerging use of photopheresis as an immune modulatory therapy. This is one of the newer innovative modifications of standard plasma exchange that will undoubtedly lead to interesting future therapeutic opportunities. The field continues to evolve. PMID- 9372127 TI - Transfusion medicine. PMID- 9372128 TI - Presynaptic proteins involved in exocytosis in Drosophila melanogaster: a genetic analysis. AB - Neuronal communication involves the fusion of neurotransmitter filled synaptic vesicles with the presynaptic terminal. This exocytotic event depends upon proteins present in three separate compartments: the synaptic vesicle, the synaptic cytosol, and the presynaptic membrane. Recent data indicate that the basic components of exocytotic pathways, including those used for neurotransmitter release, are conserved from yeast to human. Genetic dissection of the secretory pathway in yeast, identification of the target proteins cleaved by the clostridial neurotoxins and biochemical characterization of the interactions of synaptic proteins from vertebrates have converged to provide the SNARE (soluble NSF attachment protein receptor) hypothesis for vesicle trafficking. This model proposes that proteins present in the vesicle (v-SNAREs) interact with membrane receptors (t-SNAREs) to provide a molecular scaffold for cytosolic proteins involved in fusion. The hypothesis that these mechanisms function at the synapse relies largely upon in vitro evidence. Recently, genetic approaches in mice, C. elegans and the fruitfly, Drosophila melanogaster, have been used to dissect the in vivo function of numerous proteins involved in synaptic transmission. This review covers recent progress and insights provided by a genetic dissection of neurotransmitter release in Drosophila. In addition, we will provide evidence that the mechanisms for synaptic communication are highly conserved from invertebrates to vertebrates, making Drosophila an ideal model system to further unravel the intricacies of synaptic transmission. PMID- 9372129 TI - Modulation of ion currents and regulation of transmitter release in short-term synaptic plasticity: the rise and fall of the action potential. AB - Up and down-regulation of calcium and potassium conductances are associated with several forms of short-term synaptic modulation. Detailed investigation of synaptic plasticity in the marine gastropod Aplysia, and in other mollusks, indicates that synaptic transmission can be influenced in a number of ways by modulatory neurotransmitters acting through several second-messenger cascades. Modulation at the synapse itself occurs by means of the regulation of calcium current as well as through effects on processes directly involved in transmitter mobilization and exocytosis. Modulation of potassium current plays a major role in controlling neuronal excitability and may contribute to a lesser extent to the regulation of transmitter release through actions on the resting potential and on action potential configuration. PMID- 9372130 TI - Immunocytochemistry of a novel GABA receptor subunit Rdl in Drosophila melanogaster. AB - Following our recent cloning of a novel gamma-aminobutyric acid (GABA) receptor subunit gene Resistance to dieldrin or Rdl form cyclodiene resistance locus in Drosophila melanogaster, we were interested in defining its pattern of expression during development. Here we report the raising of an anti-Rdl polyclonal antibody that recognizes a single protein of the expected 65 kDa size in immunoblots of Drosophila head homogenates. In situ hybridization using Rdl cDNA probes and the anti-Rdl antibody shows that Rdl message and protein are highly expressed in the developing central nervous system (CNS) of 15-17 h embryos. Interestingly, despite the use of GABA in both the peripheral and CNS of insects, Rdl GABA receptor subunits appear to be confined to the CNS. Detailed immunocytochemistry of Drosophila brain sections showed particularly strong anti-Rdl antibody staining in the optic lobes, ellipsoid body, fan shaped body, ventrolateral protocerebrum and the glomeruli of the antennal lobes. Results are compared with the distribution of staining observed in the insect CNS with antibodies against GABA itself and synaptotagmin, a synaptic vesicle protein. PMID- 9372131 TI - Two visual pigment opsins, one expressed in the dorsal region and another in the dorsal and ventral regions, of the compound eye of a dragonfly, Sympetrum frequens. AB - This paper describes the primary structure of two visual pigment opsins (DfRh1 and DfRh2) in the regionalized compound eye of a dragonfly, Sympetrum frequens. The amino acid sequences were deduced from the nucleotide sequences of cDNAs isolated from a cDNA library of the dragonfly retina. The two opsins both consist of 379 amino acids with 81.3% identity. Analysis of hydropathy indicated that the sequences have seven transmembrane domains like those of previously described opsins. Expression analysis using RT-PCR revealed that DfRh1 was present only in the dorsal region whereas DfRh2 was detected in both the dorsal and the ventral regions of the eye. PMID- 9372132 TI - A developmental study of serotonin-immunoreactive neurons in the larval central nervous system of the spider crab Hyas araneus (Decapoda, Brachyura). AB - Larval development in crabs is characterized by a striking double metamorphosis in the course of which the animals change from a pelagic to a benthic life style. The larval central nervous system has to provide an adequate behavioural repertoire during this transition. Thus, processes of neuronal reorganization and refinement of the early larval nervous system could be expected to occur in the metamorphosing animal. In order to follow identified sets of neurons throughout metamorphosis, whole mount preparations of the brain and ventral nerve cord of laboratory reared spider crab larvae (Hyas araneus) were labelled with an antibody against the neurotransmitter serotonin. The system of serotonin immunoreactive cell bodies, fibres and neuropils is well-developed in newly hatched larvae. Most immunoreactive structures are located in the protocerebrum, with fewer in the suboesophaegeal ganglia, while the thoracic and abdominal ganglia initially comprise only a small number of serotonergic neurons and fibres. However, there are significant alterations in the staining pattern through larval development, some of which are correlated to metamorphic events. Accordingly, new serotonin-immunoreactive cells are added to the early larval set and the system of immunoreactive fibres is refined. These results are compared to the serotonergic innervation in other decapod crustaceans. PMID- 9372134 TI - Current bibliography on invertebrate neuroscience. PMID- 9372133 TI - The hybrid modulatory/pattern generating N1L interneuron in the buccal feeding system of Lymnaea is cholinergic. AB - This study examines neurotransmission between identified buccal interneurons in the feeding system of the snail Lymnaea stagnalis. We compare the pharmacology of the individual synaptic connections from a hybrid modulatory/pattern generating interneuron (N1L) to a pattern generating interneuron (N1M) with that from a modulatory interneuron (SO) to the same follower cell (N1M). The pharmacological properties of the N1L to N1M and the SO to N1M connections closely resemble each other. Both interneurons produce fast cholinergic EPSPs as judged by the blocking effects of cholinergic antagonists hexamethonium, d-tubocurarine and the cholinergic neurotoxin AF-64A. A slower, more complex but non-cholinergic component of the synaptic response is also present after stimulating either the presynaptic N1L or SO interneurons. This second component of the postsynaptic response is not dopaminergic, on the basis of its persistence in the presence of dopaminergic antagonists ergometrine and fluphenazine and the dopaminergic neurotoxin MPP+. We conclude that, although there has been an evolutionary divergence in function, the modulatory SO and the hybrid modulatory/pattern generating N1L are pharmacologically similar. Neither of them contributes directly to dopaminergic modulation of the feeding activity. These neurons also resemble the N1M protraction phase pattern generating neurons which are cholinergic (Elliott and Kemenes, 1992). PMID- 9372136 TI - The nervous system of Tricladida. I. Neuroanatomy of Procerodes littoralis (Maricola, Procerodidae): an immunocytochemical study. AB - The organization of the nervous system of Procerodes littoralis (Tricladida, Maricola, Procerodidae) was studied by immunocytochemistry, using antibodies to authentic flatworm neuropeptide F (NPF) (Moniezia expansa). Compared to earlier investigations of the neuroanatomy of tricladid flatworms, the pattern of NPF immunoreactivity in Procerodes littoralis reveals differences in the following respects: 1. Shape and structure of the brain. 2. Number and composition of longitudinal nerve cords. 3. Shape of branches of, and transverse connections between, main ventral nerve cords. 4. Composition of the pharyngeal nervous system. The rich innervation by NPF immunoreactive (IR) fibres and cells of the subepithelial muscle layer, the pharynx musculature and the musculature of the male copulatory apparatus indicates a neurotransmitter or neuromodulatory influence on muscular activity. PMID- 9372135 TI - Functional organization of cotransmission systems: lessons from small nervous systems. AB - Small invertebrate nervous systems allow one to ask a series of questions concerning the functional roles of cotransmitters. This review outlines some of the implications of cotransmission for target selectivity in complex neuropils. We suggest the possibility that a unique constellation of cotransmitters in individual identified modulatory neurons allows a specificity of action even when peptides may act over an extended distance, and when individual modulatory substances may be released from several modulatory neurons. PMID- 9372137 TI - Glutamate-mediated synaptic transmission between neuron B4 and salivary cells of Helisoma trivolvis. AB - In this study, we have further characterized the morphology and physiology of the neuroglandular synapse between the identified buccal neuron, B4, and the salivary gland of Helisoma. We demonstrate that the coupling coefficient between salivary cells within an individual acinus is approximately 1.0. We also demonstrate that synapses within the salivary gland are located near a superficial muscle layer. We examine the effects of glutamate on the salivary gland and on the B4-salivary gland EPSP. L-glutamate produces a transient, rapid onset depolarization of salivary gland cells. The response is mimicked by high concentrations of L homocysteic acid, but not by NMDA, L-aspartate, D-glutamate or kainate. The response is blocked by the presence of L- or D-glutamate in the bath, but not by CNQX, DNQX, DGG, D-AP5, or L-AP3. The depolarization is primarily dependent on the presence of calcium in the bathing solution. When either L- or D-glutamate is present in the bathing solution, the amplitude of the B4-salivary gland EPSP is reversibly reduced. The similar pharmacological properties of the response of the salivary gland to glutamate and the B4 epsp indicate that L-glutamate is a strong candidate for the fast excitatory neurotransmitter at the Helisoma neuroglandular synapse. PMID- 9372138 TI - The nervous system of Tricladida. II. Neuroanatomy of Dugesia tigrina (Paludicola, Dugesiidae): an immunocytochemical study. AB - The nervous system (NS) of Dugesia tigrina has been studied by immunocytochemical double-staining, using the authentic flatworm neuropeptide, neuropeptide F (NPF), and serotonin (5-HT) on cryosections. This technique provides a precise morphological (descriptive) account of the NS. The results show that the central nervous system is shaped like a horseshoe. The brain is composed of two lateral lobes connected by three commissures, one antero-dorsal in front of the cerebral eyes and two, more ventral, behind the eyes. The pair of main nerve cords extend from the lateral lobes of the brain to the tail end of the worm. Cross sections reveal a very close contact between lateral branches from the main cords and the submuscular plexus. Thin cord-like lateral nerves are formed by longitudinal plexal fibres. No dorsal cords were observed. The patterns of immunoreactivity to NPF and 5-HT differ from each other in several respects. In the walls of gut diverticula only NPF immunoreactive (IR) cells and fibres were observed. Only NPF immunoreactive cells occur in the parenchyma along dorso-ventral nerve fibres connecting the dorsal and ventral parts of the submuscular plexus. The number of 5-HT-immunoreactive cells associated with the main nerve cords (MCs) is greater than that of the NPF-immunoreactive cells, and the spongy structure of the MCs is more apparent following immunostaining for 5-HT. Thin 5-HT-immunoreactive fibres were observed in the subepithelial plexus, penetrating the basal lamina and innervating a rhabdite-free ventro-lateral sensory area along the body periphery. The correspondence between MCs in the lower flatworms (Catenulida and Macrostomida) and the Seriata (Tricladida and Proseriata) confirms the status of the MCs in flatworms as the most important and stable neuronal characteristic, and constitutes support for the hypothesized common origin of the MCs in flatworms. PMID- 9372139 TI - Sprouting and connectivity of embryonic leech heart excitor (HE) motor neurons in the absence of their peripheral target. AB - The rhythmic pumping of the hearts in the medicinal leech, Hirudo medicinalis, is neurogenic and mediated by a defined circuit involving identified interneurons in a central pattern generator (CPG) and segmentally iterated motor neurons that drive the heart muscle. During early embryogenesis, presumptive heart excitor (HE) motor neurons extend many axon branches into the body wall; they later innervate the heart while retracting the supernumerary peripheral axons, and only much later in development receive synaptic input from the central pattern generator (Jellies, Kopp and Bledsoe (1992) J. Exp. Biol., 170, 71-92.). In this study, HE motor neurons were deprived of an early interaction with the heart by surgical ablation of a circumscribed portion of body wall including the heart primordium. Anatomical and electrophysiological data were obtained using intracellular techniques to examine the hypothesis that peripheral interactions with the developing heart provide instructive cues for the final differentiation of these neurons. Target-deprived HE motor neurons continued to extend multiple axons in ventral, lateral and dorsal body wall throughout late embryonic and into postembryonic stages and they extended anomalous axons within the CNS. This resembles the early embryonic growth of HE motor neurons before heart tube differentiation. Furthermore, HE motor neurons deprived of heart contact exhibited tonic activity similar to the situation during early development before they are contacted by the CPG interneurons. In contrast, sham-operated and contralateral HE motor neurons oscillated normally. These results suggest that heart tube contact is specifically required for at least some aspects of HE development and provide a framework in which to identify cell-cell interactions that are involved in matching neurons and targets to generate behaviorally relevant neural circuits. PMID- 9372141 TI - Widespread anatomical projections of the serotonergic modulatory neuron, CB1, in Aplysia. AB - Although sensitization-related changes in the neural circuitry of withdrawal reflexes in Aplysia are well studied, relatively few studies address the organization of the modulatory components of sensitization. In particular, it is not known whether individual modulatory loci can simultaneously influence multiple reflex circuits. There is, however, evidence that a single modulatory transmitter, serotonin, plays a pivotal role in facilitating different reflex circuits during sensitization. Furthermore, it is known that activation of a pair of serotonergic neurons, the CB1s, produces heterosynaptic facilitation of the sensorimotor connections of one of these reflex circuits. These data together raise the possibility that the CB1s may produce sensitizing changes in the neural elements of multiple reflex systems simultaneously. In the present study, we utilized immunocytochemistry and intracellular labeling to obtain anatomical evidence of CB1's possible role in modulating multiple reflex circuits. We found that two distinct neurons satisfy previously published physiological criteria for CB1. One of these, CB1, is immunoreactive to serotonin. The second cell, here named CB2, has a different neuroanatomy and is not serotonin immunoreactive. Focusing on CB1, we found (1) profuse fine processes given off by its axons in the posterior neuropil of the cerebral ganglion, (2) extensive branching and fine processes in the pleural ganglion, and (3) a branch of CB1 that projects into the pedal ganglion. These three observations are consistent with the hypothesis that, in addition to its already established role in modulating the siphon withdrawal circuit, CB1 may also modulate synaptic connections between (1) the sensory and motor neurons of the tentacle withdrawal reflex (2) the sensory neurons and interneurons of the tail and tail-elicited siphon withdrawal reflex, and (3) the sensory and motor neurons of the tail withdrawal reflex. These observations support further physiological investigations of a possible global role of CB1 in modulating the tail and tentacle withdrawal reflexes. PMID- 9372142 TI - Current bibliography on invertebrate neuroscience. PMID- 9372140 TI - The action of philanthotoxin-343 and photolabile analogues on locust (Schistocerca gregaria) muscle. AB - The effects of philanthotoxin-343 (PhTX-343; tyrosyl-butanoyl-spermine) and photolabile analogues of this synthetic toxin on locust (Schistocerca gregaria) skeletal muscle have been investigated using whole muscle preparations (twitch contractions), single muscle fibres (excitatory postsynaptic currents (EPSCs)) and muscle membrane patches containing single quisqualate-sensitive glutamate receptors (qGluR). Analogues containing an azido group attached to either the butanoyl side-chain of PhTX-343 or as a substitute for the hydroxyl moiety of the tyrosyl residue were about 6 fold more potent antagonists than PhTX-343; those with an azido group located at the distal end of the toxin molecule were generally 2-3 fold less potent than PhTX-343. When these compounds were tested in subdued light, they were reversible antagonists of the muscle twitch, EPSC and qGluR. When a muscle was irradiated with U.V. during application of photolabile toxin combined with either neural stimulation of the muscle or L-glutamate application, antagonism of the twitch, EPSC and qGluR was complete and irreversible. PMID- 9372144 TI - Sensorin-A immunocytochemistry reveals putative mechanosensory neurons in Lymnaea CNS. AB - The pond snail Lymnaea stagnalis is a useful model system for studying the neural basis of behaviour but the mechanosensory inputs that impact on behaviours such as respiration, locomotion, reproduction and feeding are not known. In Aplysia, the peptide sensorin-A appears to be specific to a class of central mechanosensory neurons. We show that in the Lymnaea central nervous system sensorin-A immunocytochemistry reveals a discrete pattern of staining involving well over 100 neurons. Identifiable sensorin positive clusters of neurons are located in the buccal and cerebral ganglia, and a single large neuron is immunopositive in each pedal ganglion. These putative mechanosensory neurons are not in the same locations as previously identified motoneurons, interneurons or neurosecretory cells. As would be expected for a mechanoafferent, sensorin positive fibres were found in nerve tracts innervating the body wall. This study lays the foundation for future electrophysiological and behavioural analysis of these putative mechanosensory neurons. PMID- 9372143 TI - Invertebrate phosphatidylinositol-specific phospholipases C and their role in cell signaling. AB - Phosphatidylinositol-specific phospholipase C (PLC) is a family of enzymes that occupy a pivotal role in one of the largest classes of cellular signaling pathways known. Mammalian PLC enzymes have been divided into four major classes and a variety of subclasses based on their structural characteristics and immunological differences. There have been five invertebrate PLC-encoding genes cloned thus far and these fall within three of the four major classes used in categorizing mammalian PLC. Four of these invertebrate genes have been cloned from Drosophila melanogaster and one is from Artemia, a brine shrimp. Structural characteristics of the invertebrate enzymes include the presence of highly conserved Box X and Box Y domains found in major types of mammalian PLC as well as novel features. Two of the invertebrate PLC genes encode multiple splice variant subtypes which is a newly emerging level of diversity observed in mammalian enzymes. Studies of the invertebrate PLCs have contributed to the identification of the physiological functions of individual isozymes. These identified roles include cellular processes such as phototransduction, olfaction, cell growth and differentiation. PMID- 9372145 TI - Regulation of calcium currents and secretion by magnesium in crustacean peptidergic neurons. AB - The effect of varying the external Mg2+ concentration on Ca2+ currents through voltage-operated Ca2+ channels has been examined with the patch-clamp technique in acutely isolated neuronal somata from the X-organ-sinus gland (XOSG) of the crab, Cardisoma carnifex. Neurons from this neurosecretory system were selected for morphology associated with crustacean hyperglycemic hormone (CHH) content. In parallel, the effects of Mg2+ concentration on K(+)-evoked secretion of CHH from isolated, intact XOSGs have been assayed by ELISA. At physiological Ca2+ levels the high-voltage-activated Ca2+ currents were attenuated with increasing Mg2+ concentration, with 50% inhibition at approximately 75 mM. Mg2+ block was voltage dependent, relief from block occurring with increasing depolarization. Thus, in 24 mM Mg2+ inhibition of the Ca2+ current was approximately 55% at -10 mV. Secretion of CHH varied almost linearly with the log of Mg2+ concentration; in 2.4 mM Mg2+ it was double that in 24 mM Mg2+ and almost completely inhibited in 100 mM. Thus, Mg2+ produces a parallel inhibition of Ca2+ currents and CHH secretion and may play a role as a physiological modulator of neuronal activity and secretion in the XOSG of these crabs. PMID- 9372146 TI - The role of glutamate in swim initiation in the medicinal leech. AB - Antagonists were used to investigate the role of the excitatory amino acid, L glutamate, in the swim motor program of Hirudo medicinalis. In previous experiments, focal application of L-glutamate or its non-NMDA agonists onto either the segmental swim-gating interneuron (cell 204) or the serotonergic Retzius cell resulted in prolonged excitation of the two cells and often in fictive swimming. Since brief stimulation of the subesophageal trigger interneuron (cell Tr1) evoked a similar response, we investigated the role of glutamate at these synapses. Kynurenic acid and two non-NMDA antagonists, 6,7 dinitroquinoxaline-2,3-dione (DNQX) and Joro spider toxin, effectively suppressed (1) the sustained activation of cell 204 and the Retzius cell following cell Tr1 stimulation and (2) the monosynaptic connection from cell Tr1 to cell 204 and the Retzius cell, but did not block spontaneous or DP nerve-activated swimming. Other glutamate blockers, including gamma-D-glutamylaminomethyl sulfonic acid, L(+)-2 amino-3-phosphonoproprionic acid and 2-amino-5-phosphonopentanoic acid, were ineffective. DNQX also blocked both indirect excitation of cell 204 and direct depolarization of cell Tr1 in response to mechanosensory P cell stimulation. Our findings show the involvement of non-NMDA receptors in activating the swim motor program at two levels: (1) P cell input to cell Tr1 and (2) cell Tr1 input to cell 204, and reveal an essential role for glutamate in swim initiation via the cell Tr1 pathway. PMID- 9372147 TI - Inhibitory effects of nematode FMRFamide-related peptides (FaRPs) on muscle strips from Ascaris suum. AB - A large number of FMRFamide-related peptides (FaRPs) are found in nematodes, and some of these are known to influence tension and contractility of neuromuscular strips isolated from Ascaris suum body wall. Relaxation of these strips has been noted with five nematode FaRPs. The inhibitory actions of SDPNFLRFamide (PF1) and SADPNFLRFamide (PF2) appear to be mediated by nitric oxide, as previously demonstrated with inhibitors of nitric oxide synthase (NOS). This present study showed that the effects of PF1 were also depended on external Ca++ and were reduced by the Ca(++)-channel blocker verapamil, observations consistent with the finding that nematode NOS is Ca(++)-dependent. KSAYMRFamide (PF3), KNIRFamide (PF4) and KNAFIRFamide (an alanine substituted analog of KNEFIRFamide, AF1, termed A3AF1) also relaxed A. suum muscle strips, but these responses were not affected by NOS inhibitors. PF3 inhibited the activity of strips prepared from the dorsal side of the worm, but contracted ventral strips. Both effects were dependent on the presence of ventral/dorsal nerve cords (unlike PF1/PF2) and were attenuated in medium which contained high K+ or low Ca++. PF4-induced muscle relaxation and hyperpolarization were independent of nerve cords, but were reversed in Cl-free medium, unlike PF1 or PF3. The PF4 effect physiologically desensitized muscle strips to subsequent treatment with PF4 and/or GABA. However, PF4 and GABA were not synergistic in this preparation. The effects of GABA, but not PF4, were reduced in muscle strips treated with the GABA antagonist, NCS 281 93. Following PF4 (or GABA) relaxation, subsequent treatment with higher doses of PF4 caused muscle strip contraction. A3AF1 was found to relax muscle strips and hyperpolarize muscle cells independently of the ventral and dorsal nerve cords, K+, Ca++, and Cl-, and mimicked the inhibitory phase associated with the exposure of these strips to AF1. On the basis of anatomical and ionic dependence, these data have delineated at least four distinct inhibitory activities attributable to nematode FaRPs. Clearly, a remarkably complex set of inhibitory mechanisms operate in the nematode neuromuscular system. PMID- 9372148 TI - Channel gating in the absence of agonist by a homo-oligomeric molluscan GABA receptor expressed in Xenopus oocytes from a cloned cDNA. AB - We have previously described the isolation of a complementary DNA (cDNA) from the freshwater mollusc Lymnaea stagnalis encoding a polypeptide that exhibits approximately 50% identity to the beta-subunits of vertebrate gamma-aminobutyric acid (GABA) type A (GABAA) receptor. When expressed in Xenopus laevis oocytes from in vitro-transcribed RNA, the snail subunit forms functional homo-oligomeric receptors possessing chloride-selective ion channels. In recordings from voltage clamped oocytes held at -60 mV, GABA induced an inward current, whereas application of the chloride-channel blocker picrotoxin (in the absence of agonist) elicited an apparent outward current. Single channel recordings obtained from cell-attached patches have revealed a single population of approximately 20 pS channels, with an open probability greater than 90% (at a pipette potential of -100 mV) in the absence of GABA. The relationship between single channel current and pipette potential was linear over the studied range (-100 mV to +60 mV), but the open probability was less for hyperpolarizations than for depolarizations. The spontaneous channel openings were blocked by micromolar concentrations of picrotoxin. Functional hetero-oligomeric receptors were formed when the molluscan subunit was co-expressed in oocytes with the bovine GABAA receptor alpha 1 subunit, but the channels gated by these receptors did not open spontaneously. PMID- 9372149 TI - Longitudinal body wall muscles are electrically coupled across the segmental boundary in the third instar larva of Drosophila melanogaster. AB - Longitudinal body wall muscles in the third instar larva of the fruitfly, Drosophila melanogaster, were systematically examined for electrical and dye coupling. These muscle cells were found to be electrically coupled but rarely dye coupled across the segmental boundary. The inter-segmental coupling coefficients between muscle #6s and muscle #7s across the segmental boundary were 0.33 +/- 0.09 (mean +/- S.D., n = 12) and 0.43 +/- 0.09 (n = 5), respectively, which are much larger than values previously reported in Drosophila but similar to those reported in the blowfly and hawkmoth. By contrast, the intra-segmental coupling coefficient between muscles #6 and #7 was smaller, 0.16 +/- 0.08 (n = 28). Other muscle cells which had apparent physical contacts with these longitudinal muscles were examined but were not electrically coupled to them. Nerve-evoked as well as miniature excitatory junctional potentials were found also electrotonically spread across the segmental boundary. The inter-segmental coupling between muscle #6s was not blocked by the gap junction inhibitors halothane or 1-octanol. Functional significance of this electrical coupling is apparently in coordination of larval body movements. PMID- 9372150 TI - Ant opsins: sequences from the Saharan silver ant and the carpenter ant. AB - cDNA clones encoding opsins from compound eyes of carpenter ant, Camponotus abdominalis, and Saharan silver ant, Cataglyphis bombycina, were isolated from cDNA libraries. The opsin cDNAs from each species code for deduced proteins with 378 amino acids which are 92% identical. Of the 30 amino acid differences between the two proteins, 13 are non-conservative. Eight of these non-conservative substitutions are within the membrane spanning domain. The presence of a potential Schiff-base counterion in helix III in both species suggests that these opsins are the protein moiety of the visible range pigments. When compared to all known opsins, these opsins are most similar to the opsin from preying mantis (76% identity at the amino acid level). Phyletic comparisons group the two ant opsins with the other arthropod long wavelength opsins. PMID- 9372151 TI - In vitro peptidergic neurons from the adult locust pars intercerebralis: morphological and immunocytological studies. AB - Primary cell cultures were prepared from a major neurosecretory center of the adult locust brain, the pars intercerebralis, in order to characterize neurosecretory cells growing in vitro. Individual pars intercerebralis could be removed free of surrounding tissue and dissociated by mechanical treatment. Mature neurosecretory neurons of different sizes regenerate new neurites during the initial three days in vitro in serum-free medium. They show a tendency to sprout one primary neurite from which fine processes develop. By means of electron microscopy, we observed the integrity of the cellular organelles, indicating that cultured neurons are healthy, and we were able to distinguish three types of neurosecretory neurons on the basis of the ultrastructural aspects of the neurosecretory material. These three types have the same ultrastructural characteristics as in situ neuroparsin, ovary maturing parsin and locust insulin related peptide neurons. Immunogold labelling at the electron microscopic level, using the two available specific antibodies, anti-neuroparsin and anti-ovary maturing parsin, confirms the morphological characterization of neuroparsin and ovary maturing parsin cells. These results show for the first time that cultured locust neurosecretory neurons behave like those in vivo, in terms of their ultrastructure and immunocytochemistry. Moreover, the presence of recently-formed neurosecretory material both in the Golgi zone of the perikaryon and in the neuronal processes indicates that cultured neurons have functional capacity since they are able to synthesize de novo and to transport the neurosecretory material along the neurite. Thus our well-characterized culture system provides a suitable in vitro model to investigate the secretory mechanism of locust neurosecretory neurons. PMID- 9372152 TI - Expression profiling of mRNA obtained from single identified crustacean motor neurons: determination of specificity of hybridization. AB - The purpose of this study was to determine if the technique of expression profiling would allow us to determine the changes in the abundance of certain mRNAs in identifiable, single neurons as a result of heightened electrical activity. In doing so we developed an approach to test the specificity of hybridization in expression profiling. Messenger RNA from single identified crayfish motor neurons was amplified by ligation-mediated reverse transcription PCR and hybridized by dot-blotting to 45 target cDNAs from different species. As a test of specificity, the hybridization was repeated using unlabelled cDNAs, the dots were excised, and the hybridized nucleic acids were re-amplified, cloned, and sequenced to confirm their identity. By cloning and sequencing the re amplified product for each cDNA examined, one can determine the degree of background hybridization as compared to homologous hybridization. False positive results were also observed when a species-specific cDNA and highly stringent hybridization conditions were used. Our results demonstrate that ligation mediated PCR is a useful technique for checking the specificity of expression profiling. This approach can easily be adapted to any situation when confirmation of the specificity of nucleic acid hybridization is required. During this study, part of a novel crayfish neuronal actin cDNA was cloned and sequenced. PMID- 9372154 TI - Aplysia hemolymph promotes neurite outgrowth and synaptogenesis of identified Helix neurons in cell culture. AB - Hemolymph of adult Aplysia californica significantly affects neurite outgrowth of identified neurons of the land snail Helix pomatia. The metacerebral giant cell (MGC) and the motoneuron C3 from the cerebral ganglion and the neuron B2 from the buccal ganglion of H. pomatia were isolated by enzymatic and mechanical dissociation and plated onto poly-L-lysine-coated dishes either containing culture medium conditioned by Helix ganglia, or pre-treated with Aplysia hemolymph. To determine the extent of neuronal growth we measured the neurite elongation and the neuritic field of cultured neurons at different time points. Aplysia hemolymph enhances the extent and rate of linear outgrowth and the branching domain of Helix neurons. With the hemolymph treatment the MGC neuron more consistently forms specific chemical synapses with its follower cell B2, and these connections are more effective than those established in the presence of the conditioned medium. PMID- 9372155 TI - Reduced transmitter release conferred by mutations in the slowpoke-encoded Ca2(+) activated K+ channel gene of Drosophila. AB - Potassium channels control the repolarization of nerve terminals and thus play important roles in the control of synaptic transmission. Here we describe the effects of mutations in the slowpoke gene, which is the structural gene for a calcium activated potassium channel, on transmitter release at the neuromuscular junction in Drosophila melanogaster. Surprisingly, we find that the slowpoke mutant exhibits reduced transmitter release compared to normal. Similarly, the slowpoke mutation significantly suppresses the increased transmitter release conferred either by a mutation in Shaker or by application of 4-aminopyridine, which blocks the Shaker-encoded potassium channel at the Drosophila nerve terminal. Furthermore, the slowpoke mutation suppresses the striking increase in transmitter release that occurs following application of 4-aminopyridine to the ether a go-go mutant. This suppression is most likely the result of a reduction of Ca2+ influx into the nerve terminal in the slowpoke mutant. We hypothesize that the effects of the slowpoke mutation are indirect, perhaps resulting from increased Ca2+ channel inactivation, decreased Na+ or Ca2+ channel localization or gene expression, or by increases in the expression or activity of potassium channels distinct from slowpoke. PMID- 9372156 TI - Identification of two novel genes specifically expressed in the D-group neurons of the terrestrial snail CNS. AB - A search for genes specifically expressed in the giant interneurons of parietal ganglia of the snail Helix lucorum yielded, among others, two genes named HDS1 and HDS2. According to data obtained by Northern hybridization and whole-mount in situ hybridization, both genes are neurospecific and expressed almost exclusively in the peptidergic D-group neurons (Sakharov, 1974) located in the right parietal ganglion. In situ hybridization of the HDS1 and HDS2 probes with CNS of several related species of the Helicoidea superfamily identified in all cases similarly located homologous groups of neurons. Sequencing of the near full-length cDNA copies of the HDS1 and HDS2 genes revealed open reading frames 107 and 102 amino acids long for HDS1 and HDS2, respectively. Both putative proteins contain a hydrophobic leader peptide and putative recognition sites for furin-like and PC like endopeptidases. Predicted amino acid sequences of the HDS1 and HDS2 proteins were found to be moderately homologous to each other, as well as to the LYCP preprohormone expressed by the light yellow cells of the freshwater snail Lymnaea stagnalis. These results confirm an earlier hypothesis that the D-group of the Helix family and the light yellow cells of Lymnaea stagnalis represent homologous neuronal groups. Our data suggest that the HDS1 and HDS2 genes encode precursors of secreted molecules, most likely neuropeptides or neurohormones. PMID- 9372158 TI - Distribution of two GABA receptor-like subunits in the Drosophila CNS. AB - Previously we have described the distribution of the Rdl GABA receptor subunit in the Drosophila CNS. Knowing that Rdl can coassemble with LCCH3 (a Drosophila GABA receptor-like subunit showing sequence similarity to vertebrate beta subunit GABAA receptors) in baculovirus infected insect cells, we compared the localization of these two receptor subunits in order to identify any potential overlap in their spatial or temporal distribution. The two subunits show very different patterns of localization. Early in development LCCH3 is found in the majority of developing neuroblasts and later is localized to the cell bodies of the embryonic nerve cord and brain, and the neuronal cell bodies surrounding the adult brain. In contrast, Rdl receptor subunits appear confined to the neuropil in all developmental stages. These results have two important implications. Firstly, they suggest that although these two subunits can coassemble in heterologous expression systems, they may not be found in the same tissues in the nervous system. Secondly, production of LCCH3 before neuronal differentiation leads us to speculate on the role of that LCCH3 containing receptors in the developing nervous system. PMID- 9372157 TI - Temporal and spatial expression patterns of two G-protein coupled receptors in Drosophila melanogaster. AB - Temporal and spatial expression patterns of a muscarinic acetylcholine receptor (Acr60C) and an octopamine/tyramine receptor (Octyr) were determined in Drosophila melanogaster using quantitative Northern analysis and in situ hybridization to tissue sections. Expression of mRNA encoding both of these G protein coupled receptors peaks initially in 18 to 21 hour embryos following the formation of the mature larval nervous system. Levels of mRNA then decline during larval stages, rising to a second peak in 3 to 4-day-old pupae after a period of major nervous system reorganization. The muscarinic acetylcholine receptor mRNA is expressed throughout the cortical regions of the central nervous system in adults and embryos. Particularly high levels of expression of Acr60C are observed in cell bodies adjacent to the antennal lobes, suggesting a major role for this muscarinic receptor in the processing of olfactory information. In contrast, the octopamine/tyramine receptor mRNA is distributed diffusely throughout the adult brain, with patches of signal concentrated in the cortex of the dorsal protocerebrum near the mushroom bodies. These patches may represent individual cells expressing Octyr receptors. PMID- 9372153 TI - Voltage gated calcium channels in molluscs: classification, Ca2+ dependent inactivation, modulation and functional roles. AB - Molluscan neurons and muscle cells express transient (T-type like) and sustained LVA calcium channels, as well as transient and sustained HVA channels. In addition weakly voltage sensitive calcium channels are observed. In a number of cases toxin or dihydropyridine sensitivity justifies classification of the HVA currents in L, N or P-type categories. In many cases, however, pharmacological characterization is still preliminary. Characterization of novel toxins from molluscivorous Conus snails may facilitate classification of molluscan calcium channels. Molluscan preparations have been very useful to study calcium dependent inactivation of calcium channels. Proposed mechanisms explain calcium dependent inactivation through direct interaction of Ca2+ with the channel, through dephosphorylation by calcium dependent phosphatases or through calcium dependent disruption of connections with the cytoskeleton. Transmitter modulation operating through various second messenger mediated pathways is well documented. In general, phosphorylation through PKA, cGMP dependent PK or PKC facilitates the calcium channels, while putative direct G-protein action inhibits the channels. Ca2+ and cGMP may inhibit the channels through activation of phosphodiesterases or phosphatases. Detailed evidence has been provided on the role of sustained LVA channels in pacemaking and the generation of firing patterns, and on the role of HVA channels in the dynamic changes in action potentials during spiking, the regulation of the release of transmitters and hormones, and the regulation of growth cone behavior and neurite outgrowth. The accessibility of molluscan preparations (e.g. the squid giant synapse for excitation release studies, Helisoma B5 neuron for neurite and synapse formation) and the large body of knowledge on electrophysiological properties and functional connections of identified molluscan neurons (e.g. sensory neurons, R15, egg laying hormone producing cells, etc.) creates valuable opportunities to increase the insight into the functional roles of calcium channels. PMID- 9372159 TI - Glutamate as a transmitter in the sensory pathway from prostomial lip to serotonergic Retzius neurons in the medicinal leech Hirudo. AB - The involvement of glutamate in putative ingestive sensory pathways affecting the excitability of serotonergic Retzius neurons (RZ) in the leech CNS was investigated with a pharmacological approach. Exposure of the prostomial lip to 150 mM NaCl and 1 mM arginine produced excitatory as well as inhibitory responses in RZ found in the reproductive segments, while only excitatory responses were elicted in standard midbody RZ. Antagonists of glutamatergic receptors of the kainate/quisqualate type effectively inhibited chemosensory dependent excitation of RZ. Antagonists of glutamatergic receptors of the N-methyl D-aspartate type were ineffective in this regard. Cephalic nerve stimulation, like chemical stimulation of the lip, produced segment-specific responses in midbody RZ. Both the polysynaptic and monosynaptic components of the excitatory response of standard midbody RZ following cephalic nerve stimulation were inhibited in the presence of the kainate/quisqualate antagonist DNQX. These data suggest a role for glutamate as a transmitter in the neural circuitry from receptors of the leech prostomial lip to serotonergic RZ. PMID- 9372160 TI - Coiled mechanoreceptors in Aplysia revealed by sensorin immunofluorescence and confocal microscopy. AB - Identified mechanosensory neurons of Aplysia are established model neurons for studies on learning and memory, and for examining responses to axonal injury. Although many characteristics of these sensory neurons have received intensive study, the nature of the peripheral mechanoreceptive endings remains unknown. Identification of a peptide, sensorin, specific in Aplysia for mechanosensory neurons, led to the development of an antibody which proved useful in studying the peripheral morphology of these neurons. Immunostaining for sensorin in tail body wall revealed that sensorin is present in peripheral arborizations. Examination of sensorin-positive fibers in the periphery revealed that they terminate as coiled structures in the muscle layer of the body wall. These coiled structures (approximately 0.5 microns diameter processes, 2-3 microns across the coil, approximately 60 microns long) run parallel to muscle fibers and have a pitch of about one turn per 4 microns. Sensorin immunostaining was particularly intense in varicosities, both along peripheral fibers and along the coiled structure. The localization of sensorin suggests that it may be released peripherally where it could have various paracrine and/or autocrine neuromodulatory actions. PMID- 9372161 TI - Modulation of swimming speed in the pteropod mollusc, Clione limacina: role of a compartmental serotonergic system. AB - In locomotory systems, the central pattern generator and motoneuron output must be modulated in order to achieve variability in locomotory speed, particularly when speed changes are important components of different behavior acts. The swimming system of the pteropod mollusc Clione limacina is an excellent model system for investigating such modulation. In particular, a system of central serotonergic neurons has been shown to be intimately involved in regulating output of the locomotory pattern generator and motor system of Clione. There are approximately 27 pairs of serotonin-immunoreactive neurons in the central nervous system of Clione, with about 75% of these identified. The majority of these identified immunoreactive neurons are involved in various aspects of locomotory speed modulation. A symmetrical cluster of pedal serotonergic neurons serves to increase wing contractility without affecting wing-beat frequency or motoneuron activity. Two clusters of cerebral cells produce widespread responses that lead to an increase in pattern generator cycle frequency, recruitment of swim motoneurons, activation of the pedal serotonergic neurons and excitation of the heart excitor neuron. A pair of ventral cerebral neurons provides weak excitatory inputs to the swimming system, and strongly inhibits neurons of the competing whole-body withdrawal network. Overall, the serotonergic system in Clione is compartmentalized so that each subsystem (usually neuron cluster) can act independently or in concert to produce variability in locomotory speed. PMID- 9372162 TI - Molecular and immunological characterization of a Gq protein from ventral and lateral eye of the horseshoe crab Limulus polyphemus. AB - GTP binding proteins of the Gq family have been implicated in phototransduction in rhabdomeral photoreceptors. In this study we used molecular and immunochemical techniques to characterize a GTP-binding protein alpha subunit of the Gq family in ventral and lateral photoreceptors of the horseshoe crab, Limulus polyphemus. Both ventral photoreceptors and lateral eye retinular cells became strongly labeled with an antibody directed against the common carboxyl tail of two Gq family proteins, G alpha q and G alpha 11. This antibody also labeled a 42 kDa band on Western blots of proteins from ventral photoreceptor cell bodies, ventral photoreceptor axons, lateral eyes and lateral optic nerves. The reverse transcription-polymerase chain reaction (RT-PCR), along with degenerate oligonucleotide primers designed against conserved regions of known G alpha q and G alpha 11 proteins, was used to isolate a cDNA from ventral eye RNA which encodes a protein with high identity to known Gq proteins. Ribonuclease protection assays showed that the corresponding message was expressed in ventral eye, but these assays, as well as Northern blots, failed to detect expression in lateral eye. Therefore, while photoreceptors of both ventral and lateral eyes contain a Gq-like protein, the mRNA encoding the Gq protein in the ventral eye may differ in nucleotide sequence from its lateral eye counterpart. PMID- 9372163 TI - Anatomical pathways connecting lip sensory structures and central nervous system in hirudinid leeches visualized by carbocyanine dyes and laser scanning confocal microscopy. AB - Chemoreception in Hirudo medicinalis is thought to be mediated by ciliated cells grouped in sensory structures, the sensilla, arranged in bands on the animal's dorsal lip (Elliott, 1986; Zipser et al., 1994). Furthermore, chemical and/or thermal stimulation of the dorsal lip in reduced preparations evokes changes in the electrical activity of the cephalic nerves that connect the head with the central nervous system. However, the complete trajectory by which the sensory afferents reach the cerebral ganglia has not been demonstrated anatomically. In this study, we traced these pathways following retrograde and/or anterograde transport of carbocyanine dyes (DiI, DiA and DiD) in the cephalic nerves of Hirudo medicinalis and a closely related species, Macrobdella decora. While information regarding Macrobdella's chemoreception is scarce, the two species show some differences with regard to their chemical preferences. Dyes were applied to the sensillar structures along the dorsal lip, or to the cut ends of individual cephalic nerves in fixed preparations that included the lip and attached nerves with or without the head ganglia. After a two week incubation, specimens were mounted and imaged using a confocal microscope. The results show that the axons of the sensory neurons in the sensilla project through the four pairs of cephalic nerves. The sensillar projections are however more numerous in the dorsal nerves than they are in the ventral ones. In addition, the organization of the sensillar bands, the morphology of the pathways and the sensory structures themselves appear to be identical for Hirudo and Macrobdella and therefore the behavioral differences in response to appetitive stimuli cannot be readily explained by differences in morphology. PMID- 9372164 TI - Biomechanical implications of mineral content and microstructural variations in cortical bone of horse, elk, and sheep calcanei. AB - BACKGROUND: Artiodactyl and perissodactyl calcanei have been recently introduced as models for examining bone for mechanically mediated adaptation. We have reported substantial regional variations in cortical bone microstructure and mineral content within the same cross-section of mule deer calcanei. In part, these variations may be adaptations accommodating the customary presence of predominantly tension, compression, and shear strain modes in mutually exclusive cortical locations. Calcanei from skeletally mature horses, elk, and sheep were examined in order to corroborate these previous findings. METHODS: From each species, one calcaneus was obtained from each of 13 animals. Each bone was cut transversely near mid-shaft into two segments and examined for mineral (ash) content. From each species, an additional segment obtained from each of 7 of the original 13 bones was examined for microstructure using 50x backscattered electron images. Regions examined included the compression (cranial), tension (caudal), and medial and lateral (shear) cortices. Periosteal (P), middle (M), and endosteal (E) regions were also examined separately within the compression and tension cortices. Quantified microstructural parameters included: (1) secondary osteon population density (OPD), (2) fractional area of secondary bone (FASB), (3) porosity, (4) population density of new remodeling events (NRE = resorption spaces and newly forming secondary osteons), and (5) secondary osteon diameter and minimum-to-maximum chord ratio. RESULTS: Results in each species showed variations that are considered to be mechanically important and are similar to those reported in mule deer calcanei. Mineral content data suggest that remodeling activity in the compression, medial, and lateral cortices was occurring at a slower rate than remodeling in the tension cortex. In comparison to the tension cortices, the compression cortices have approximately 6.0% higher mineral content (P < 0.007) and 35% higher OPD (P < 0.01). Additionally, the compression cortices have more nearly perfectly round osteons and lower FASB, porosity, NRE, and osteon diameter (P < 0.05; except for FASB in horse where P = 0.087 and NRE in sheep where P = 0.520). However, patterns of microstructural variations between intracortical regions (P, M, E) are inconsistent when compared to data reported in mule deer calcanei. Microstructural characteristics between the medial and lateral cortices were similar although some significant differences were identified. In general, the microstructure of the medial and lateral cortices differ from the neighboring compression and tension cortices. CONCLUSIONS: Differences in mineral content and microstructure between opposing compression and tension cortices of these three species resemble differences previously reported in mule deer calcanei. The majority of the microstructural variations can be explained in the context of strain-magnitude-based rules of Frost's Mechanostat Theory of mechanically induced bone adaptation. These variations may also be strongly influenced by the strain mode predominating in each cortical location. The hypothesis that intracortical material adaptations are correlated with progressive transcortical strain magnitude variations is not supported by the inconsistent transcortical variations in material organization. These interpretations do not preclude the possibility that other specific strain features may contribute to a complex adaptive signal. PMID- 9372165 TI - Computer simulation of subchondral bone adaptation to mechanical loading in an incongruous joint. AB - BACKGROUND: We hypothesized that the typically bicentric distribution of subchondral bone density (i.e., two maxima) in incongruous joints with deeper sockets could be predicted by a computer simulation employing a concavely incongruous finite-element model and current bone remodeling theory. Additional objectives were to assess the uniqueness of the solution with respect to assumed model parameters and initial conditions and to determine the relationship between contact areas, subchondral bone stress, and subchondral bone density patterns. METHODS: An idealized model of the humeroulnar joint was constructed with a quantitatively realistic representation of its natural incongruity. A currently accepted remodeling theory was implemented with a finite-element code using a node-based approach. RESULTS: The simulation predicted a dense subchondral bone plate after application of 3,000 daily load cycles for 300 days. The pronounced bicentric distribution of subchondral mineralization emerged. The solution was virtually independent of the initial density distribution and other assumed model parameters. Furthermore, the model predicted high tensile stresses in the subchondral bone, when the joint socket was spread apart during loading. Therefore, the locations of maximal strain energy density in the subchondral bone did not correspond with areas of joint contact. CONCLUSIONS: The results of the bone remodeling simulations are consistent with patterns of subchondral bone density determined experimentally. Furthermore, the solutions exhibited a high degree of uniqueness, were rather insensitive to changes in cartilage stiffness, moderately sensitive to number of applied loading cycles, and highly sensitive to loading magnitude. Tensile stresses seem to play a dominant role in subchondral bone remodeling due to bending in the subchondral bone plate. Thus, we conclude that, in the case of an incongruous joints with deeper sockets, the density of the subchondral bone cannot be regarded as a direct measure of the adjacent articular pressure. PMID- 9372166 TI - Lumen formation during angiogenesis in vitro involves phagocytic activity, formation and secretion of vacuoles, cell death, and capillary tube remodelling by different populations of endothelial cells. AB - BACKGROUND: We have utilised an in vitro model of angiogenesis to investigate the morphological changes which occur during the formation of a lumen in capillary tubes. METHODS AND RESULTS: On collagen 1 gel in the presence of phorbol myristate acetate (PMA) and anti-alpha 2 beta 1 antibody, cell aggregation and alignment takes place within two hours of plating. The initial apparently homogeneous population of endothelial cells (EC) actually display at least three distinct phenotypes. One population, characterised by a phagocytic phenotype, migrated through the gel creating channels and defines the extent of the capillary network. These are later enveloped by a second population of cells characterised by intracellular vacuoles. The ultimate fate of these vacuoles is fusion with the plasma membrane. By 12 hours the original phagocytic cell population undergoes cell death, which morphologically appears apoptotic in nature. A consequence of the secretion of vacuoles and programmed cell death is the extensive remodelling of the capillary tubes, resulting in expansion of the intercellular space into a lumen. The remodelling results in 45% of the EC membrane contacting the lumenal surface at the expense of EC-EC and EC-matrix contact. A third population of cells implant between the EC involved in lumen formation and thus expand the size of the capillary tube. CONCLUSION: Thus, in the formation of a mature multicellular lumen we have identified a number of key events. First, cell-cell contact is essential in order to define the intercellular space. Second, at least three morphologically distinct subpopulations of ECs are involved. Third, vacuole formation and programmed cell death are required for expansion of the intercellular space which ultimately becomes the lumen. PMID- 9372167 TI - Quantitation of shock wave lithotripsy-induced lesion in small and large pig kidneys. AB - BACKGROUND: Shock wave lithotripsy (SWL) is known to cause injury to the kidney. However, it is not known how lesion size varies as the parameters of SWL treatment (number of shocks, kilovoltage, kidney size) are changed. This hypothesis could not be tested because there was no method available to quantitate accurately the SWL-induced renal lesion. METHODS: A dosage of 2,000 shocks at 24 kV delivered by an unmodified Dornier HM3 lithotripter was applied to the lower pole calyx of the right kidney of small and large pig kidneys. A new method was developed to embed a whole pig kidney for serially sectioning, recording, and digitization. Automated computer color recognition made it possible to discriminate regions of hemorrhage from undamaged tissue and allowed quantitation of the lesion in single sections and in the entire kidney. RESULTS: The new protocol resulted in an accurate identification of sites of hemorrhage and calculations of the volume fraction of injured renal tissue. Lesion size induced in small kidneys was significantly larger than that induced in the larger kidneys (7.6 +/- 1.2% and 1.6 +/- 0.7%, respectively). CONCLUSIONS: Computer segmentation of serially sectioned SWL-treated kidneys has determined that kidney size is a risk factor for enhanced renal injury. PMID- 9372168 TI - A unique parotid gland in Hart's little fruit bat, Enchisthenes hartii. AB - BACKGROUND: Hart's little fruit bat, Enchisthenes hartii, is uncommon and, although it has been the subject of recent molecular genetic studies, is little known biologically. Because chiropteran salivary glands vary interspecifically in ways that reflect evolutionary history and ecology, we examined the parotid gland in E. hartii to ascertain the extent to which it resembles homologous glands in species to which this bat presumably is related. METHODS: The parotid glands were prepared for electron microscopic examination by conventional means. RESULTS: The parotid gland of E. hartii is structurally unique among all previously studied species of bats (> 230 species examined) and other mammals. In contrast to the same gland in other mammals, the parotid gland in E. hartii lacks secretory endpieces. In their place, there is a type of striated duct. Thus, in this species single secretory elements consist of (proceeding in the direction of salivary flow): striated duct--intercalated duct--and a conventionally located striated duct. The proximal ducts possess microvillus-lined intercellular canaliculi, whereas the walls of the distal ducts include occasional dark cells. Some small serous-like granules may be present in the intercalated duct cells. CONCLUSIONS: The function(s) and biological role of the unique parotid gland in E. hartii are unknown. Nevertheless, the presence of two sets of striated ducts provides two separate glandular components seemingly capable of electrolyte transport. This might be of adaptive significance in enabling this species to make use of tropical nutrient resources that otherwise would be unavailable. The uniqueness of its parotid glands lends support to the current hypothesis that E. hartii should be classified as a monotypic genus rather than as a species of Artibeus, whose members it resembles morphometrically. PMID- 9372169 TI - Ultrastructure of the adrenal cortex of hibernating, arousing, and euthermic dormouse, Muscardinus avellanarius. AB - BACKGROUND: The adrenal gland is a key organ for hibernation (a condition characterized by striking reduction of body functions). Very limited information is available on the fine structure of the gland during hibernation and on the periodical arousal from hibernation. METHODS: Dormice (Muscardinus avellanarius) were maintained in an external animal house and allowed to hibernate spontaneously (November). Arousal was induced in March by exposure to daylight. Euthermic, active dormice were captured in June. The adrenals were taken from four hibernating, three arousing, and four euthermic dormice and processed for resin embedding. The ultrastructure of the adrenal cortex was investigated by transmission electron microscopy. RESULTS: In the zona glomerulosa of hibernating and arousing dormice, the smooth endoplasmic reticulum was prominent in comparison with euthermic animals, and mitochondria showed abundant vesicular cristae. The zona fasciculata and zona reticularis did not show consistent differences, apart from a lower cell lipid content in the outer portion of zona fasciculata of arousing dormice. CONCLUSIONS: The zona glomerulosa showed signs of increased activity during hibernation. This finding is supported by previous biochemical data demonstrating increased production of renin and aldosterone during such extreme physiological conditions. Activation of the zona glomerulosa in hibernation is probably adaptive to a condition of drastically reduced salt intake. PMID- 9372170 TI - Neurotrophin receptor-like proteins in Peyer's patches. AB - BACKGROUND: The neurotrophins are a family of growth factors that act on responsive cells through specific high-affinity signal-transducing receptors called Trk (A, B, and C) proteins. The neurotrophin receptor proteins are widely distributed in both nervous and nonnervous tissues, including the lymphoid organs. The expression of these receptor proteins by a cell population is an indication of responsiveness to the respective binding neurotrophin. The present study investigated the presence and cellular localization of high-affinity neurotrophin receptor proteins in equine and bovine Peyer's patches. METHODS: Peyer's patches from horse and cow intestine were fixed in Bouin's fixative, embedded in paraffin cut 10 microns thick, and studied immunohistochemically using rabbit polyclonal antibodies against specific epitopes of the intracellular domain of the Trk receptor proteins. RESULTS: Immunoreactivity (IR) for Trk-like proteins was found in specific cell populations in Peyer's patches. TrkA-IR in the horse was localized in dendritic cells of the interfollicular T-cell zones and in follicular dendritic cells of the lymphoid follicles; in the cow, TrkA-ir was present in reticulum cells. TrkB-like IR was present in cells found inside lymphoid follicles of the horse, probably reticulum cells. Furthermore, in both species, TrkB-IR was found in interstitial dendritic cells and/or macrophages of the intestinal lamina propria. No specific TrkC-like immunostaining was found in immunocompetent cells of Peyer's patches. CONCLUSIONS: Present findings demonstrate that, as in other lymphoid organs, the accessory nonlymphoid cells express immunoreactivity for high-affinity neurotrophin receptor proteins. These results seem to favor the notion that neurotrophins, especially nerve growth factor, could have a physiological role in secondary lymphoid organs, possibly acting on accessory cells and not directly on lymphocytes. PMID- 9372171 TI - TrkA neutrophin receptor protein in the rat and human thymus. AB - BACKGROUND: Increasing evidence suggests that nerve growth factor (NGF), and probably other neurotrophins, are involved in the control of lymphoid organs and immunocompetent cells that express neurotrophins and/or their receptors. In the rat thymus, mRNA for TrkA (an essential component of the NGF signal transducing receptor) has been found primarily in stromal cells. The present study was undertaken to analyze the occurrence and localization of TrkA in the rat and human thymus, using Western blot and immunohistochemical techniques. METHODS: Thymuses from human fetuses (estimated gestational ages of 29 and 32 weeks) and newborns (3 and 4 weeks old), as well as from 3-month-old rats were used. Human and rat samples were fixed in buffered 10% formaldehyde, paraffin-embedded, and processed for immunohistochemistry. Moreover, rat thymus samples were processed for Western blot analysis. RESULTS: A protein band consistent with full-length TrkA (approximately 140 kDa) was detected in the rat thymus. Immunoreactivity (IR) for TrkA was exclusively found in thymic epithelial cells of both rat and human, identified because they also displayed cytokeratin IR. Interestingly, species-specific differences were noted for the expression of TrkA in different subtypes of thymic epithelial cells. Apparently, no immunolabelling was observed in other stromal cells or in lymphocytes. CONCLUSIONS: These results suggest that TrkA ligands may be involved in the control of thymic epithelial cells. This could be of potential importance because of the involvement of these cells in providing an appropriate microenvironment for maturation and selection of T lymphocytes. PMID- 9372172 TI - Remodeling of junctional complexes during the development of the outer blood retinal barrier. AB - BACKGROUND: The retinal pigment epithelium (RPE) forms the outer blood-retinal barrier by separating the neural retina from fenestrated capillaries in the choroid. The barrier depends upon tight junctions within the apical junctional complexes that bind neighboring cells. During development, permeability decreases as the apical junctional complex gradually matures. To investigate this process, the composition of the apical junctional complex was monitored during RPE development in chicken embryos. METHODS: Permeability was monitored by incubating freshly isolated RPE/choroid in medium containing horseradish peroxidase followed by histochemical staining and electron microscopy. The expression of the tight junction proteins, ZO-1 and occludin, was determined by immunofluorescence and immunoblotting. Development of the RPE apical junctional complex was to compared to the homologous complex that forms the outer limiting membrane of the neural retina. RESULTS: The apical junctional complex of the RPE was permeable to horseradish peroxidase until embryonic day 10-12. Two putative forms of ZO-1 had approximately the same molecular mass as mammalian ZO-1 and were present in the apical junctional complexes at different stages of development. We identified one form as ZO-1, because it was present in mature RPE and shared an epitope with the rodent isoforms, ZO-1 alpha+ and ZO-1 alpha-. The second form lacked this epitope but was identified by a polyclonal antibody to ZO-1. It was designated the ZO-1 like protein (ZO-1LP). On embryonic day 3, occludin and ZO-1LP were observed along the apical surface of the neuroepithelium that gave rise to the RPE and the neural retina. In the neural retina, occludin expression decreased just before inner segments were formed, but ZO-1LP expression continued in the outer limiting membrane throughout development. During RPE development, occludin expression was constant or increased slightly. By contrast, ZO-1LP was gradually replaced by ZO 1 and total ZO-1 immunoreactive proteins decreased more than 10x. CONCLUSIONS: A gradual change in the composition of the apical junctional complexes accompanied the period of barrier formation. In RPE, ZO-1 gradually replaced ZO-1LP, but the decrease in ZO-1 expression suggests its functions during junction formation are not directly related to junction permeability. By contrast, occludin was lost and ZO-1LP retained where an adherens junction forms the permeable, outer limiting membrane. PMID- 9372173 TI - Developing human biliary system in three dimensions. AB - BACKGROUND: In the development of the human biliary system, although the extrahepatic bile ducts develop from the embryonic hepatic diverticulum, there is increasing evidence to suggest that the intrahepatic bile ducts originate within the liver from the ductal plate. The ductal plate develops as a sheath of primitive biliary epithelium in the mesenchyme along the portal vein branches. Through an orderly process of selection and deletion, the ductal plate is remodelled into the adult system of anastomosing tubular bile ducts. The ductal plate remodelling process occurs at the porta hepatis between 11 and 13 weeks of gestation and progresses towards the periphery of the liver. METHODS: In this project, for the first time, we have used computerised three-dimensional reconstruction techniques to visualise the developing human biliary system. Paraffin-embedded tissue from eight human embryos or fetuses between 5.5 and 16 weeks of gestation were serially sectioned, and their images were aligned, digitised, and used for three-dimensional reconstruction. RESULTS AND CONCLUSIONS: Three-dimensional images of the extrahepatic and the intrahepatic biliary systems were obtained, and the following conclusions were drawn. (1) The intrahepatic biliary system, both at the porta hepatis and within the liver, developed from the ductal plate through a consistent pattern of remodelling. (2) Prior to the remodelling process, the ductal plate was of similar morphology irrespective of site and gestation. (3) The extrahepatic biliary system was in direct luminal continuity with the developing intrahepatic biliary system throughout gestation and did not show the presence of a "solid stage" in any of the embryos or fetuses studied. PMID- 9372174 TI - Ontogeny of milky spots in the human greater omentum: an immunochemical study. AB - BACKGROUND: Milky spots in the human greater omentum are preformed specific accumulations of primarily macrophages within the stroma of the greater omentum. To obtain a better understanding of milky spots in the human greater omentum, the development and the earliest forms of milky spots in the human greater omentum were studied, with special attention to the macrophage population. METHODS: Specimens of human greater omentum were obtained from fetuses of 20 to 40 weeks gestation and one newborn three days old (n = 6). Using mature macrophages (RFD 7), activated macrophages (RFD 1), B-lymphocytes (CD 22), and T-lymphocytes (CD 2), and immunoperoxydase labeling, the percentage of these cells in developing milky spots and the development of milky spots were studied by light microscopy. A time-dependent increase in the percentage of positive staining cells and the size of clusters was analyzed using the non-parametric Spearman rank correlation test. RESULTS: Small accumulations of cells with about 50% monocytes/macrophages were present at 20 weeks of gestation. With increasing gestational age the number of clusters of cells increased significantly (P < 0.01) as well as their size (P < 0.01). Starting at 29 weeks, vascularized clusters of cells were seen; true milky spots were present at 35 weeks. A significant (P < 0.05) increase in the percentage of mature macrophages was found in developing milky spots, whereas no activated macrophages were seen. The percentage of B-lymphocytes and T lymphocytes found in the clusters of cells and milky spots increased significantly (P < 0.05) but did not exceed 10% of the total number of cells. CONCLUSIONS: From our data it can be concluded that milky spots are specific structures in the greater omentum formed between the 20th and 35th week of gestation. Further, we concluded that immature cells (promonocytes) mature locally in developing milky spots. PMID- 9372175 TI - Deflation reflex: description and clinical significance. AB - BACKGROUND: During our study of the defecation mechanism, we found that the external anal sphincter contracted not only upon rectal inflation but also upon deflation. As this reflex relationship was reproducible, it was studied to elucidate its clinical significance in the light of its function. METHODS: A catheter with a condom at its end was introduced into the rectum of 16 healthy volunteers (mean age 45.2 years). The EMG response of the external anal sphincter to rapid rectal inflation and deflation was studied by means of a concentric needle electrode inserted into the muscle. The procedure was repeated in eight subjects after sphincter infiltration with xylocaine or saline. RESULTS: The external sphincter contracted twice on rectal distension: once on inflation and another time on deflation. The amplitude increased and latency decreased with increasing rectal inflation, while neither was affected on deflation. The anesthetized sphincter did not respond, while the saline-infiltrated sphincter responded to rectal distension. CONCLUSIONS: The deflation reflex functions to interrupt or terminate the act of defecation. It may prove of diagnostic significance in defecation disorders. PMID- 9372176 TI - Ontogenesis and cytomorphology of the nasal olfactory organs in the Oman shark, Iago omanensis (Triakidae), in the Gulf of Aqaba, Red Sea. AB - BACKGROUND: Sharks (Selachi) are among the largest predators in deep and shallow seas, feeding on live and dead prey. Olfaction is one of the central senses by which they forage, especially at night and in deep water. The organs responsible for this function are the olfactory rosettes, which are situated in their nares. This study follows the ontogenesis and cytological development of the olfactory rosettes of the Oman shark, Iago omanensis, found in the Gulf of Aqaba, Red Sea, at depths of 150-1500 m. METHODS: The sharks were collected bimonthly by means of a specially designed vertical standing net and sacrificed by an overdose of MS222. The olfactory rosettes were extracted from the adults and embryos, then fixed and prepared for EM and LM studies. RESULTS: Iago is a placental, matrotrophic species with a maximal dimension of 800 mm TL (total length). It reproduces all year round, giving birth to a maximum of four (occasionally five) young of 170-180 mm TL. In newborn and adult fish the nasal olfactory organs are as described for other sharks, composed of olfactory lamellae with secondary folds. The number of lamellae increases during embryogenesis up to a maximum of 28-32 in adults. The primary nasal placodes first appear in larvae of 10-14 mm on the dorso-lateral part of the head and then become gradually displaced to the ventral position, typical for adults. Ontogenesis of the nasal rosettes is characterized by a gradual development of the lamellae and their secondary folds, with a concomitant ripening of the sensory elements (ciliated, microvillar, and rod-like bearing cells), as well as glandular and supporting cells and cells containing kinocilia that agitate the nasal water flow. CONCLUSIONS: The released young possess functional olfactory organs and developed neural transmission across the olfactory bulb and tract, to the olfactory lobes in the brain, enabling them to forage from birth. Presented data show the occurrence in I. omanensis of two types of ciliated and microvillar cells. Ciliated and rod bearing sensory neurons are described for the first time in sharks. PMID- 9372177 TI - Computer-based neuroanatomy laboratory for medical students. AB - BACKGROUND: To present the laboratory portion of our first-semester Human Neuroanatomy course at Temple University Medical School more effectively and efficiently and to replace the glass slide/microscope-based laboratory component of the course, we developed a computer-based substitute. METHODS: For this computer-based neuroanatomy laboratory program, we photographed the (a) gross brain sliced and dissected specimens and (b) all the glass slides, from the sacral cord through the head of the caudate nucleus. We digitized the photographed images and, using Multimedia ToolBook (Asymetrix), created a computerized atlas, laboratory guide, and a clinical problem-solving section. To assess the effectiveness of the computerized laboratory, we compared student performances between those classes that previously had the traditional laboratory with two succeeding classes that used the computer-based laboratory. RESULTS: Test score results of the laboratory portion of the course suggested that performance on laboratory material was virtually unchanged by the substitution of the computer program. By a survey taken at the end of the course, the students were very satisfied with the computerized program as a teaching method. CONCLUSIONS: The students and faculty enthusiastically agreed that the computer program was an effective substitute method for the traditional glass-slide laboratory and that it was a beneficial self-educational tool that fostered independent learning. The program encouraged student interaction and group learning and fostered independence. It was a more efficient method for faculty and students without sacrificing performance. PMID- 9372178 TI - MADS domain proteins in plant development. AB - The MADS domain (MCM1, AGAMOUS, DEFICIENS, and SRF, serum response factor) is a conserved DNA-binding/dimerization region present in a variety of transcription factors from different kingdoms. MADS box genes represent a large multigene family in vascular plants. In angiosperms, many of the genes of the MADS family are involved in different steps of flower development, most notably in the determination of floral meristem and organ identity. The roles that MADS box genes play, however, are not restricted to control the development of the plant reproductive structures. The genetic, molecular, and biochemical basis of the action of the MADS domain proteins in the plant life cycle are reviewed here. PMID- 9372180 TI - six-banded, a novel Drosophila gene, is expressed in 6 segmental stripes during embryonic development and in the eye imaginal disc. AB - We have characterised a Drosophila P-element enhancer detector insertion F125, which is expressed in the embryonic head and CNS as well as in various third instar imaginal discs. In an attempt to identify the gene with the equivalent expression pattern, we have characterised an adjacent gene. It encodes two novel conceptual proteins: Type I (1182 amino acids) and Type II, representing a shorter form of 774 amino acids truncated at both termini relative to Type I that is generated by alternative splicing. Based on its embryonic expression pattern, the gene was called six-banded (sba). Both splice forms are expressed in a unique embryonic pattern: initially as 6, then 12 stripes during early stages of embryonic development. Subsequently, expression is found in the developing trachae and during larval development is restricted to the eye imaginal disc where both transcripts are present immediately anterior to and behind the morphogenetic furrow. While sba expression in the eye antennal disc is mirrored by the expression of the adjacent F125 P-element, other patterns reported by this enhancer detector are not mimicked by the sba gene suggesting that the expression of the P-element represents a 'composite' of the effects of nearby enhancers. PMID- 9372179 TI - Glutaminyl-tRNA synthetase. AB - Among the twenty aminoacyl-tRNA synthetases glutaminyl-tRNA synthetase occupies a special position: it is one of only two enzymes of this family which is not found in all organisms, being mainly absent from gram positive eubacteria, archaebacteria and organelles. The E. coli GlnRS is relatively small with 553 amino acids and a molecular mass of 64.4 kDa and functions as a monomer. The mammalian enzymes are somewhat larger and can be parts of multienzyme complexes. Crystal structures were solved of E. coli GlnRS complexed with tRNA(Gln) and ATP, of this complex containing tRNA(Gln) replaced by unmodified tRNA(Gln), and of three complexes with mutated GlnRS enzymes. The GlnRS molecule consists of four domains, the catalytic site is located in the Rossman fold, typical for class I synthetases, and the reaction mechanism follows the normal adenylate pathway. The enzyme shows many similarities with glutamyl-tRNA synthetase; a common ancestor of both molecules is well established. In the E. coli system recognition of the cognate tRNA has been studied in many details using both natural and artificial mutants of tRNA(Gln) and of the enzyme: GlnRS recognizes mainly conventional parts of the tRNA molecule, namely some bases of the anticodon loop and parts of the acceptor stem. PMID- 9372181 TI - Activation of mitochondrial 2-oxoacid dehydrogenases by thioredoxin. AB - The regulation of mitochondrial dehydrogenases of 2-oxoacids by thioredoxin is established. It is found that at low NAD+ and saturating concentrations of 2 oxoacids and CoA, inactivation of 2-oxoacid dehydrogenase complexes takes place, preventing NAD+ reduction under such conditions. However, addition of oxidized E. coli thioredoxin to the reaction medium without dithiothreitol allows effective NAD+ reduction at this substrate ratio. Product accumulation curves show that thioredoxin activates the complexes by protecting them from the inactivation observed in the conditions when the complex-bound dihydrolipoate is accumulated. Disappearance of the activatory effect of thioredoxin after its treatment with SH specific reagents indicates the involvement of the redox-active cysteine couple of thioredoxin in its activation of 2-oxoacid dehydrogenase complexes. The redox inactive thioredoxin not only shows no activation, but in fact exerts an inhibitory effect. The inhibition manifests the complex formation between SH modified thioredoxin and dehydrogenase systems, involving amino acid residues of thioredoxin other than cysteine. High efficiency of thioredoxin from E. coli as compared to chloroplast thioredoxin f and glutathione disulfide is revealed. This indicates the importance of specific protein structure also for the influence of the redox-active thioredoxin upon the 2-oxoacid dehydrogenase complexes. The results obtained suggest that these key enzyme systems of mitochondrial metabolism represent previously unidentified targets for the action of mitochondrial thioredoxin, which is known to resemble the E. coli counterpart studies in this work. PMID- 9372182 TI - Differential immunological cross-reactions with antisera against the V-ATPase of Kalanchoe daigremontiana reveal structural differences of V-ATPase subunits of different plant species. AB - Two antisera (ATP88 and ATP95) raised against the V-ATPase holoenzyme of Kalanchoe daigremontiana were tested for their cross-reactivity with subunits of V-ATPases from other plant species. V-ATPases from Kalanchoe blossfeldiana, Mesembryanthemum crystallinum, Nicotiana tabacum, Lycopersicon esculentum, Citrus limon, Lemna gibba, Hordeum vulgare and Zea mays were immunoprecipitated with an antiserum against the catalytic V-ATPase subunit A of M. crystallinum. As shown by silver staining and Western blot analysis with ATP88, subunits A, B, C, D and c were present in all immunoprecipitated V-ATPases. In contrast, ATP95 recognized the whole set of subunits only in K. blossfeldiana, M. crystallinum, H. vulgare and Z. mays. This differential cross reactivity of ATP95 indicates the presence of structural differences of certain V-ATPase subunits. Based on the Bafilomycin A1-sensitive ATPase activity of tonoplast enriched vesicles, and on the amount of V-ATPase solubilized and immunoprecipitated, the specific ATP-hydrolysis activity of the V-ATPases under test was determined. The structural differences correlate with the ability of V-ATPases from different species to hydrolyze ATP at one given assay condition for ATP-hydrolysis measurements. Interestingly V-ATPases showing cross-reactivity of subunits A, B, C, D and c with ATP95 showed higher rates of specific ATP hydrolysis compared to V-ATPases containing subunits which were not labeled by ATP95. Thus, V-ATPases with high turnover rates in our assay conditions may show common structural characteristics which separate them from ATPases with low turnover rates. PMID- 9372183 TI - Introduction of a proline residue into position 31 of the loop of the dimeric 4 alpha-helical protein ROP causes a drastic destabilization. AB - The exchange of an alanine with a proline residue in position 31 of the loop region of the dimeric 4-alpha-helical-bundle protein ROP causes a reduction in the alpha-helix content of 7% and a reduction in stability of about 40% compared to the wild type parameters. The Gibbs energy of unfolding by denaturants extrapolated linearly to zero denaturant concentration, delta G0D (buffer, 25 degrees C), has been determined to be 43 kJ (mol dimer)-1. The corresponding ROPwt value is 72 kJ (mol dimer)-1 (Steif et al., 1993). The extrapolated delta G0D values obtained from urea and GdmHCI un- and refolding studies are identical within error limits. Deconvolution of the stability values into enthalpy and entropy terms resulted in the following parameters. At T1/2 = 43 degrees C (Cprotein = 0.05 mg.ml-1) the ROP A31P mutant is characterized by delta Hv.H.0 = 272 kJ (mol dimer)-1, delta Cp = 7.2 kJ (mol dimer)-1 K-1, delta S0 = 762 J (mol dimer)-1 K-1. These parameters are only approximately 50% as large as the corresponding values of ROPwt. We assume that the significant reduction in stability reflects the absence of at least one hydrogen bond as well as deformation of the protein structure. This interpretation is supported by the reduction in the change in heat capacity observed for the A31P mutant relative to ROPwt, by the increased aggregation tendency of the mutant and by the reduced specific CD absorption at 222 nm. All results support the view that in the case of ROP protein the loop region plays a significant role in the maintenance of native structure and conformational stability. PMID- 9372184 TI - A lethal mutant of the catabolite gene activator protein CAP of Escherichia coli. AB - The dimeric catabolite gene activator protein (CAP) of Escherichia coli uses its recognition helix to bind with each subunit the DNA sequence motif 5' G-7T-6G-5A 4 3'. It makes a direct amino acid-base contact with E181 and cytosine in position-5' on the reverse strand. While testing mutants of CAP in position 181 for specificity changes, we found that CAP E181Q is lethal in high amounts for the E. coli strains we used for cloning. We cloned this CAP mutant successfully in cya- strains, where CAP is inactive. Examination of the in vitro binding activities of CAP E181Q, and of in vivo activity when present in low, non-lethal amounts, revealed loss of specificity but not of binding capacity for its DNA targets. It binds well to CAP consensus with G or T in position-5, better to CAP consensus with A, C in position-5, quite well to lambda consensus operator with G in position-7 and rather weakly to lambda consensus. PMID- 9372186 TI - In vitro mutagenesis of binding site elements for the clock-controlled proteins CCTR and Chlamy 1. AB - The luciferin-binding protein (LBP) from the dinoflagellate, Gonyaulax polyedra, is regulated by a circadian clock at the translational level. A 22-nucleotide long interval in the lbp 3' untranslated region, which contains seven UG-repeats, was characterized as a circadian cis-acting element, to which a clock controlled factor (CCTR) binds. Recently we have found that the phylogenetically distant green alga, Chlamydomonas reinhardtii, contains a CCTR analog, called Chlamy 1. Here we show that the flanking nucleotides surrounding the UG-repeats are required for high binding activity of CCTR and Chlamy 1. The absence of three or more UG-repeats abolishes binding with both proteins. PMID- 9372185 TI - On the mechanism of rebounding of calcium in liver mitochondria. AB - Rat liver mitochondria are able to temporarily lower the steady state concentration of external Ca2+ after having accumulated a pulse of added Ca2+. This could be due to inhibition of efflux or/and stimulation of influx of Ca2+. This question has been addressed in mitochondria respiring on succinate +/- malonate. In the presence of malonate the depression of the membrane potential during Ca2+ uptake is more extensive and the rate of Ca2+ uptake slower. There were no discernible differences in the rates of efflux either after inhibition of the calcium uniporter by Ruthenium Red or by studying efflux of preloaded 45Ca labeled Ca2+. The efflux was not changed by diltiazem or cyclosporin A to inhibit Ca2+ exchange on the Ca2+/nNA+ antiporter or efflux through the permeability transition pore. It is concluded that the rebounding is due mainly to stimulation of the calcium uniporter. PMID- 9372187 TI - SNAP-25 can self-associate to form a disulfide-linked complex. AB - SNAP-25 is expressed in neurons and endocrine cells and is essential for exocytosis of neurotransmitters and peptide hormones. It has been shown to be involved in several interactions with other proteins of the secretion machinery. Here we show that SNAP-25 can self-associate to form a disulfide-linked complex. Complex formation is facilitated in vitro (in concentrated extracts or by immunoprecipitation). SNAP-25 complexes, however, also form when intact cells are treated with a membrane-permeable crosslinker indicating that SNAP-25 molecules exist in close proximity in vivo and could form complexes spontaneously. We also show that monomeric SNAP-25 and disulfide-linked SNAP-25 complexes are palmitoylated and that both can be cleaved by botulinum neurotoxin E. PMID- 9372188 TI - The DnaJ60 gene of Drosophila melanogaster encodes a new member of the DnaJ family of proteins. AB - In eukaryotes the DnaJ homolog constitute a family of proteins with diverse functions which all appear to involve the chaperone activity of Hsp70. Here, we report the molecular characterization of DnaJ60, a gene located at 60C on the right arm of the second chromosome of Drosophila melanogaster and encoding a putative protein of 217 amino acids with a molecular mass of 27.7-kDa and a pl of 10.5. The N-terminal region of the DnaJ60 protein displays a significant sequence similarity with the J domain of DnaJ proteins and contains a centrally located hydrophobic segment suggesting the occurrence of a membrane spanning domain. Northern blot analysis detected a 0.75-kb transcript which is weakly expressed in embryos, larvae and females but intensively expressed in adult males. In situ localization revealed that the DnaJ60 transcript is highly expressed in male testes and the ejaculary bulb but at an undetectable level in ovaries suggesting that the DnaJ60 protein may play an important function during spermatogenesis and/or in the male genital tract. PMID- 9372189 TI - Autokinase activity of alpha-crystallin inhibits its specific interaction with the DOTIS element in the murine gamma D/E/F-crystallin promoter in vitro. AB - In a previous report we demonstrated the in vitro interaction of alpha-crystallin with an element downstream of the transcriptional initiation site (DOTIS) of the murine gamma E-crystallin promoter (Pietrowski et al., 1994, Gene 144, 171-178). The aim of the present study was to investigate the influence of phosphorylation on this particular interaction. We could demonstrate that the autophosphorylation of alpha-crystallin leads to a complete loss of interaction with the DOTIS element, however, PKA-dependent phosphorylation of alpha-crystallin is without effect on the interaction. It is hypothesized that the autophosphorylation of alpha-crystallin might be involved in regulatory mechanisms of the murine gamma D/E/F-crystallin gene expression. PMID- 9372190 TI - Cloning and characterization of a dominant-negative vps1 allele of the yeast Saccharomyces cerevisiae. AB - The gene product of the yeast VPS1 gene is a member of a family of high-molecular weight GTP-binding proteins that are involved in diverse cellular processes. The Vps1 protein (Vps1p) was shown to perform an essential function in the yeast secretory pathway. Here, we report the isolation and characterization of a mutant allele of the VPS1 gene, causing a dominant-negative vacuolar protein sorting (vps) defect, as demonstrated by the mislocalization of the vacuolar hydrolase carboxypeptidase Y (CPY). DNA sequence analysis of the mutant vps1 allele (vps1d 293) revealed a single point mutation, resulting in an amino acid exchange at position 293 from Ala to Asp. The mutation is located downstream of the tripartite GTP-binding motif found in the amino-terminal half of the protein. The observation that expression of wild-type Vps1p partially suppressed the dominant negative CPY sorting phenotype indicates competition of a non-functional mutant Vps1 protein and a functional wild-type VPS1p for a Vps1p-binding site of an as yet unknown vacuolar protein sorting factor. PMID- 9372191 TI - Subsite specificity studies on the unusual cysteine protease clostripain: charged residues in the P3 position indicate a narrow subsite region. AB - The importance of electrostatic interactions between charged residues at the P3 position of substrates and the S3 subsite of the cysteine protease clostripain was investigated. For this purpose quantitative enzymatic hydrolysis studies using steady state kinetics have been carried out within a set of N alpha protected synthetic dipeptide ester substrates with systematic changes of their charge in the P3 position. It was demonstrated that, in contrast to the former postulated second anionic S3 subsite, the lowest specificity was for the hydrolysis of the positively charged substrates. However, this effect was strongly dependent on the individual amino acid at P1. Furthermore, we investigated how far these P3-S3 interactions reflect on the S' subsite specificity via acyl transfers. Apart from the general weak influence of the charge at P3 on the deacylation kinetics, nucleophiles with proline at P'1 play an extraordinary role. Surprisingly, in contrast to the poor primary lysine specificity, acyl transfer using P1 lysine substrates does not affect the nucleophile efficiency found with the corresponding arginine substrates. PMID- 9372192 TI - Thermal denaturation of human cystatin C and two of its variants; comparison to chicken cystatin. AB - Thermal denaturation of the recombinant human cystatin C, an 8-residue shorter variant (Leu-9 cystatin C), and the W106S mutant were measured using differential scanning calorimetry (DSC). The finding that Leu-9 cystatin C is of similar stability to the full length protein is in accordance with its nearly normal inhibitory activity. The variant W106S cystatin C exhibits a higher melting temperature by 4 degrees than the wild-type protein. This contrasts with its reduced inhibitory activity and represents an example where activity changes are due to local effects and are not correlated to stability. From the ratio between Van't Hoff and calorimetric enthalpies it is judged that recombinant human cystatin C and Leu-9 cystatin C are dimeric prior to thermal unfolding whereas W106S cystatin C is monomeric. Melting temperatures and estimated stabilities for some other members of the cystatin superfamily of the cysteine proteinase inhibitors are presented which have been recorded previously or were collected for this study (chicken cystatin). It is concluded that thermal stability of human cystatin C (Tm = 82 degrees C) is placed in between the more stable human stefin A (Tm = 95 degrees C) and the less stable human stefin B (Tm = 66 degrees C) whereas chicken cystatin behaves as a thermophilic protein, melting above 115 degrees C. To illustrate secondary structure changes, thermal denaturations of the recombinant human cystatin C and of W106S cystatin C were followed by circular dichroism in the far UV. It was found that the change in tertiary structure (revealed by DSC) precedes the major change in secondary structure. PMID- 9372193 TI - Site-directed mutagenesis of the Cys residues in ClpA, the ATPase component of protease Ti (ClpAP) in Escherichia coli. AB - The ATP-dependent casein hydrolysis by protease Ti (ClpAP) has been shown to be inhibited by sulfhydryl blocking agents, such as N-ethylmaleimide (NEM), when preincubated with ClpA but not with ClpP. To define the role of three Cys residues in ClpA, site-directed mutagenesis was performed to substitute each of them with Ser or Ala. None of the mutations showed any effect on the ATPase activity of ClpA or its ability to support the casein degradation by ClpP. However, NEM could no longer block the ability of ClpA/C47S or ClpA/C47A in supporting the ClpP-mediated proteolysis, unlike that of ClpA, ClpA/C203S, or ClpA/C243S. Furthermore, in the presence of NEM, casein could stimulate the ATPase activities of ClpA/C47S and ClpA/C47A and protect from their degradation by ClpP, but not of the other ClpA proteins. These results suggest that the inhibitory effect of NEM is due to prevention of the interaction of ClpA with casein by introduction of a bulky alkyl group to Cys47, but not linked to the catalytic function of the ATPase. PMID- 9372194 TI - Complementary anchor PCR of rearranged variable T-cell receptor beta-chain cDNA regions. AB - Sequencible amplificates comprising the variable cDNA sequences of the rearranged T-cell receptor (TCR) beta-chain were obtained from the T-leukemia cell line Jurkat using a single-sided PCR approach based on five synthetic oligonucleotides derived from the flanking constant sequence. Double-stranded cDNA was cleaved by a restriction enzyme creating cohesive ends, to which an anchor oligonucleotide was ligated. Since this anchor was complementary to the antisense strand of the known constant region, exclusively the desired ligation product folded into a stem-loop-structure that was enzymatically extended to yield a PCR template, now flanked at both ends by primer binding sites appropriate for nested PCR. PMID- 9372195 TI - Chronic intraventricular infusion with NGF improves LTP in old cognitively impaired rats. AB - Aged (21 months) cognitively-impaired male Sprague-Dawley rats received intraventricular infusion of nerve growth factor (NGF) or cytochrome C (Cit C) for 14 or 28 days using miniosmotic pumps and were evaluated either 1 week or 3 months after treatment. Groups of untreated young, aged-impaired and aged non impaired rats were also evaluated. Under narcose recording and stimulating electrodes were stereotactically implanted in the dentate gyrus and the perforant path. The stimulation intensity was individually adjusted to obtain a half maximal population spike (P) for test stimuli and a quarter-maximal for tetanization. The amplitude and latency of P and the slope (S) of the field EPSP were determined before and at 2, 5, 15, 30 and 60 min after tetanization at 400 Hz. Paired stimuli at 30 ms interval were also applied before and after tetanization. Aged, cognitively impaired rats showed an absent S potentiation and a delayed P potentiation, both in amplitude and latency, while non-impaired rats behaved like the young controls. Paired pulse inhibition showed no difference among groups before or after tetanization suggesting that the impaired potentiation is not due to an increased retroactive inhibition. NGF treatment ameliorates LTP deficits to levels equivalent to non-impaired rats, while Cit C controls showed no improvement. No differences appear among NGF treated groups, but evidence suggest that the animals evaluated 3 months after treatment developed a stronger potentiation. PMID- 9372196 TI - 5-HT inhibits lateral entorhinal cortical neurons of the rat in vitro by activation of potassium channel-coupled 5-HT1A receptors. AB - Serotonin (1-40 microM) reduced input resistance by 20.6 +/- 6% and hyperpolarized stellate and pyramidal neurons of layers two and three of the lateral entorhinal cortex. 5-Carboxamidotryptamine, a 5-HT1 agonist, and the selective 5-HT1A agonist 8-hydroxy-dipropylaminotetralin mimicked the action of serotonin. The reversal potential of 5-HT-mediated hyperpolarizations was sensitive to the extracellular K+ concentration, indicating a potassium conductance change. Serotonin treatment suppressed excitatory amino acid-mediated synaptic potentials (by 48%, Kd = 6.9 microM) and responses to exogenously applied glutamate (70.1 +/- 17% of control, n = 7), but did not alter paired pulse facilitation, indicating a postsynaptic site of action. Intracellular application of QX-314, a blocker of potassium conductance, significantly reduced depression of synaptic potentials by 5-HT agonists. In cells filled with QX-314, responses to exogenously applied glutamate were not reduced by serotonin or 5 carboxamidotryptamine application. These results indicate that the observed conductance increase associated with 5-HT application accounts for most if not all of the observed depressant effects of 5-HT1A agonists on excitatory amino acid-mediated neurotransmission. PMID- 9372197 TI - Difference in brown adipose tissue effector response and associated thermoresponsiveness of ventromedial hypothalamic (VMH) neurons of 21 degrees C vs. 4 degrees C acclimatized rats to scrotal thermal stimulation. AB - The present study was designed (1) to determine if scrotal thermal stimulation would activate brown adipose tissue (BAT) thermogenesis, indicated by increases in interscapular BAT temperature (TIBAT) of cold acclimatized (CA, kept at 4 degrees C for 4 weeks) and room temperature acclimatized rats (RA, kept at 21 degrees C for 4 weeks) and (2) to compare the thermoresponsiveness of VMH neurons of both groups to scrotal heating and cooling. VMH extracellular activity was recorded in male RA and CA Sprague-Dawley rats when scrotal temperatures (Tsc) were changed between 5-40 degrees C via localized thermode (3 mm2) along with measurements of TscS and TIBATS. The CA-group showed significant increases in TIBATS during scrotal cooling compared to respective TIBATS of the RA-group. The ratio of VMH warm responsive (WRN), cold responsive (CRN) and temperature non responsive (TNRN) neurons in the CA-group changed compared to that in the RA group as a greater percentage of CRNs occurred in the CA-group. Also, the thermoresponsiveness of individual VMH CRNs of the CA rats was significantly increased compared to VMH CRNs of the RA-group. The results indicated that localized scrotal cooling of CA-rats (not RA-rats) can activate BAT thermogenesis. Furthermore, VMH CRNs increased their thermoresponsiveness with chronic cold exposure which may be an important neuronal adaptive response for the subsequent enhanced BAT thermogenic effector response seen in that group. PMID- 9372198 TI - Harmaline competitively inhibits [3H]MK-801 binding to the NMDA receptor in rabbit brain. AB - Harmaline, a beta-carboline derivative, is known to produce tremor through a direct activation of cells in the inferior olive. However, the receptor(s) through which harmaline acts remains unknown. It was recently reported that the tremorogenic actions of harmaline could be blocked by the noncompetitive NMDA channel blocker, MK-801. This study examined whether the blockade of harmaline's action, in the rabbit, by MK-801 was due to a pharmacological antagonism at the MK-801 binding site. This was accomplished by measurement of [3H]MK-801 binding in membrane fractions derived from tissue containing the inferior olivary nucleus and from cerebral cortex. Harmaline completely displaced saturable [3H]MK-801 binding in both the inferior olive and cortex with apparent IC50 values of 60 and 170 microM, respectively. These IC50 values are consistent with the high doses of harmaline required to produce tremor, e.g., 10-30 mg/kg. Non-linear curve fitting analysis of [3H]MK-801 saturation experiments indicated that [3H]MK-801 bound to a single site and that harmaline's displacement of [3H]MK-801 binding to the NMDA receptor was competitive as indicated by a shift in Kd but not in Bmax. In addition, a Schild plot gave a slope that was not significantly different from 1 indicating that harmaline was producing a displacement of [3H]MK-801 from its binding site within the NMDA cation channel and not through an action at the glutamate or other allosteric sites on the NMDA receptor. These findings provide in vitro evidence that the competitive blockade of harmaline-induced tremor by MK 801 occurs within the calcium channel coupled to the NMDA receptor. Our hypothesis is that harmaline produces tremor by acting as an inverse agonist at the MK-801 binding site and thus opening the cation channel. PMID- 9372199 TI - Bilateral coupling in learned blinking: effects of lesion aimed at callosal disconnection of the cat motor cortex. AB - The effects of selective transection of the rostralmost portion of the corpus callosum, which contains fibers interconnecting the motor cortices of the two hemispheres, on interocular temporal coupling in the initiation of learned symmetrical blinking were examined in 5 cats trained to blink in response to a 500-ms tone paired with 100-ms airpuffs randomly delivered to either eye (alternate airpuff; 3 animals) or simultaneously directed to both eyes (bilateral airpuff; 2 animals) 400 ms after tone onset. Lesioning had no effect on ability to respond, but did cause a significant increase in the mean conditioned response (CR) latencies of both eyes in all subjects. In the intact cats, a statistically significant difference between the mean CR latencies of the two eyes (hereafter called side superiority) was found in three animals, two of which exhibited superiority of the left eye. After lesioning, it was found that the right eye proved superior to the left eye in four subjects. Both before and after lesioning, side superiority was not due to the ability of one eye to give CRs consistently shorter than those of the other eye, but it crucially depended on the higher proportion of trials in which the superior eye led. A linear correlation between CR latencies of the right and left eye was found in all animals both before and after lesioning. It is suggested that subsequent to lesioning aimed at callosal disconnection of the motor cortex, the effects on initiation of learned symmetrical blinking are the consequences of withdrawal of both bilaterally balanced modulatory influences to both eyes and lateralized modulatory influences to the left eye. PMID- 9372200 TI - Cholecystokinin induces Fos expression in catecholaminergic neurons of the macaque monkey caudal medulla. AB - Systemic administration of cholecystokinin octapeptide (CCK) slows gastric emptying, inhibits feeding, and stimulates pituitary hormone release in rats and primates. To characterize the central neural circuits that mediate these effects in primates, the present study analyzes the distribution and chemical phenotypes of caudal medullary neurons that are activated in rhesus and cynomolgus macaque monkeys after CCK treatment. Monkeys were injected intravenously with CCK (3 or 15 micrograms/kg b.wt) or vehicle solution (0.15 M NaCl), then were anesthetized and perfused with fixative 75 min later. Coronal tissue sections through the caudal medulla were processed for immunocytochemical localization of the immediate-early gene product Fos as a marker of stimulus-induced neuronal activation, and were double-labeled for tyrosine hydroxylase to identify catecholaminergic cells. Many neurons in the area postrema, nucleus of the solitary tract, and ventrolateral medulla were activated to express Fos in monkeys after CCK treatment, similar to previous reports in rats. Treatment activated neurons included substantial proportions of the A1/C1 and A2/C2 catecholaminergic cell groups, whereas neurons in the locus coeruleus (A6 cell group) were not activated. These results indicate that the autonomic, behavioral, and neuroendocrine effects produced by systemic administration of CCK involve hindbrain neural systems whose anatomical and chemical features are comparable in rats and primates. PMID- 9372201 TI - Functional injury of cholinergic, GABAergic and dopaminergic systems in the basal ganglia of adult rat with kaolin-induced hydrocephalus. AB - Structural and/or functional injury of the basal ganglia can lead to motor functional disabilities, abnormal gait and posture, and intellectual/emotional impairment, disorders also frequently seen in hydrocephalus. Previous reports have documented changes in dopamine levels in the neostriatum in experimental hydrocephalus. The present study was designed to investigate possible functional injury of cholinergic, GABAergic and dopaminergic systems in the basal ganglia immunohistochemically in a model of kaolin-induced hydrocephalus. Hydrocephalus was induced in 12 Wistar rats by intracisternal injection of 0.05 ml volume of 25% kaolin solution under microscopic guidance. Four controls received an equal volume of sterile saline. The animals were killed at 2, 4 and 8 weeks after injection. The numbers of choline acetyltransferase (ChAT)- and glutamic acid decarboxylase (GAD)-immunoreactive (IR) neostriatal neurons and tyrosine hydroxylase (TH)-IR nigral neurons, were counted in 60-micron thick representative sections and the IR cellular densities (counted cell number/neostriatal area) were calculated in the neostriatum. The number of total neostriatal neurons was also counted in 15-micron thick sections stained by cresyl violet (Nissl staining) to calculate the cellular density. The number and cellular density of neostriatal ChAT-IR neurons were significantly reduced at 2, 4, and 8 weeks after injection (P < 0.05), while those of GAD-IR neurons decreased at 4 and 8 weeks (P < 0.05). There was a linear correlation between degree of ventricular enlargement, and reduction in number of ChAT- and GAD-IR neurons (P < 0.001) as well as in the cellular density (P < 0.001). However, Nissl staining revealed no reduction in the cellular density of total neostriatal neurons (P < 0.001). TH immunoreactivity was reduced in neostriatal axons and in nigral compacta neurons, particularly in the medial portion of the dopaminergic nigrostriatal pathway. These findings suggest that progressive hydrocephalus results in functional injuries of cholinergic and GABAergic neurons in the neostriatum and dopaminergic neurons in the substantia nigra compacta by mechanical distortion. The disturbance in balance of these neurotransmitter systems in the basal ganglia may explain some of motor functional disabilities in hydrocephalus. PMID- 9372202 TI - Characterization of the long-lasting activator protein-1 complex induced by kainic acid treatment. AB - Kainic acid is known to induce seizures, neuronal damage and cell loss in the rat hippocampus. Our laboratory has shown that a single kainic acid injection elicits acute increases of activator protein-1 DNA-binding activity and this activity stays at an elevated level for 2 weeks after kainic acid injection. However, some pathological changes such as mossy fiber sprouting do not occur until 2-3 weeks after the kainic acid injection and the specific transcription factors regulating the long-term events after kainic acid treatment are not clear. To determine the involvement of activator protein-1 transcription factors in the long-term events after kainic acid treatment, gel mobility-shift and Western blot analyses were used. The results showed that two activator protein-1 complexes with different mobilities occur during the acute stage. However, only the faster-migrating complex as well as the 35-37-kDa fos-related antigen and Jun-D proteins were seen during the late stage. These results suggest that different activator protein-1 complexes exist at different stages after convulsions and that they regulate ensembles of different genes. PMID- 9372203 TI - Effects of REM sleep deprivation on the d-amphetamine-induced self-mutilating behavior. AB - It is well known that self-mutilating behavior (SMB) is developed in rats and humans during the daily treatment with d-amphetamine. Accordingly, in this work it was found that the daily treatment with 7.5 mg/kg d-amphetamine induced in rats a progressive appearance of SMB. Lower doses (5.0 mg/kg) were uneffective and higher doses (10 mg/kg) produced a pattern of SMB in which the mutilation induced at the beginning of the d-amphetamine administration disappears completely as the treatment progresses. Interestingly, it was also found that REM sleep deprivation (48 h) potentiated significantly the SMB induced by the daily administration of 7.5 mg/kg d-amphetamine, and to lesser extent, the SMB induced by the daily treatment with 10 mg/kg d-amphetamine. R(+)-SCH-23390 a D1 dopamine (DA) receptor antagonist blocked completely or abolished the SMB induced by 7.5 mg/kg d-amphetamine in REM sleep deprived rats while (+/-)-sulpiride a D2 DA receptor antagonist had only a partial blocking effect. Haloperidol a D1/D2 DA receptor antagonist behaved as a D1 antagonist. Our results indicate that REM sleep deprivation enhances the SMB induced by the daily administration of d amphetamine and suggest the involvement of D1 DA receptors in the mechanism underlying the SMB. A role of REM sleep deprivation is also suggested in the appearance of self-mutilating episodes in d-amphetamine addicts. PMID- 9372205 TI - Down-regulation of the amyloid protein precursor of Alzheimer's disease by antisense oligonucleotides reduces neuronal adhesion to specific substrata. AB - The hallmark of Alzheimer's disease is the cerebral deposition of amyloid which is derived from the amyloid precursor protein (APP). The function of APP is unknown but there is increasing evidence for the role of APP in cell-cell and/or cell-matrix interactions. Primary cultures of murine neurons were treated with antisense oligonucleotides to down-regulate APP. This paper presents evidence that APP mediates a substrate-specific interaction between neurons and extracellular matrix components collagen type I, laminin and heparan sulphate proteoglycan but not fibronectin or poly-L-lysine. It remains to be determined whether this effect is the direct result of APP-matrix interactions, or whether an intermediatry pathway is involved. PMID- 9372204 TI - The effect of in vivo ethanol consumption on cyclic AMP and delta-opioid receptors in mouse striatum. AB - In this study the effect of in vivo ethanol consumption on cyclic AMP (cAMP) and [D-Ala2,D-Leu5]enkephalin (DADLE) inhibition of forskolin-stimulated cAMP production was examined in mouse striatum. Effects of ethanol on striatal delta opioid receptor (DOR) density and mRNA were also examined. Mice had unlimited access to 7% (v/v) ethanol alone or water for 1 or 7 days and were then sacrificed and striatum removed for analysis. There was no difference in basal cAMP formation between water and ethanol-treated mouse striatum following 7 day treatment, and a small, but statistically significant increase in basal cAMP in the ethanol group following 1 day treatment. Both 1 day and 7 day ethanol treatment did not significantly alter the percentage increase in cAMP following treatment with 10 microM forskolin. There was a significant effect of ethanol treatment on the maximum inhibitory effect of DADLE on forskolin-stimulated cAMP formation following both 1 and 7 day ethanol treatment. The DADLE IC50 was unaffected by ethanol treatment. Saturation binding studies ([3H]Deltorphin II) indicated no effect of ethanol on Bmax or Kd in striatum. Similarly, no difference between water and ethanol-treated was observed for DOR mRNA in striatum. These data indicate that ethanol consumption can alter opioid regulation of cAMP formation. However, this effect is not related to changes in any delta-opioid receptor parameters that were examined. PMID- 9372206 TI - Sleep/waking effects of a selective 5-HT1A receptor agonist given systemically as well as perfused in the dorsal raphe nucleus in rats. AB - Sleep/waking stages and behavior were studied following the selective 5-HT1A agonist 8-OH-DPAT given subcutaneously (s.c.) (0.010-0.375 mg/kg) as well as perfused continuously (10 microM) for 6 h into the dorsal raphe nucleus (DRN) using microdialysis. Given systemically, 8-OH-DPAT at 0.375 mg/kg s.c. induced 5 HT behavioral syndrome, increased waking to 149% and reduced slow wave sleep (SWS) to 86%, transition to 76% and rapid eye movement (REM) sleep to 73%. The effect on deep SWS (SWS-2) was biphasic, with an increase after 2 h. 8-OH-DPAT at 0.010 mg/kg did not have any vigilance effects. 8-OH-DPAT perfusion in DRN produced a fourfold increase in REM sleep compared to perfusion of artificial cerebrospinal fluid. This is consistent with the hypothesis that reduced 5-HT neurotransmission following 5-HT1A autoreceptor stimulation will disinhibit cholinergic REM-promoting mesopontine neurons and thereby lead to a REM sleep increase. The other sleep/waking stages were not significantly affected by 8-OH DPAT perfusion in DRN. PMID- 9372207 TI - The CRF1 receptor mediates the excitatory actions of corticotropin releasing factor (CRF) in the developing rat brain: in vivo evidence using a novel, selective, non-peptide CRF receptor antagonist. AB - Corticotropin releasing factor (CRF) is the key coordinator of the neuroendocrine and behavioral responses to stress. In the central nervous system, CRF excites select neuronal populations, and infusion of CRF into the cerebral ventricles of infant rats produces severe age-dependent limbic seizures. These seizures, like other CRF effects, result from activation of specific receptors. Both of the characterized members of the CRF receptor family (CRF1 and CRF2), are found in the amygdala, site of origin of CRF-induced seizures, and may therefore mediate these seizures. To determine which receptor is responsible for the excitatory effects of CRF on limbic neurons, a selective, non-peptide CRF1 antagonist was tested for its ability to abolish the seizures, in comparison to non-selective inhibitory analogues of CRF. Pretreatment with the selective CRF1 blocker (NBI 27914) increased the latency and decreased the duration of CRF-induced seizures in a dose-dependent manner. The higher doses of NBI 27914 blocked the behavioral seizures and prevented epileptic discharges in concurrent electroencephalograms recorded from the amygdala. The selective CRF1 blocker was poorly effective when given systemically, consistent with limited blood-brain barrier penetration. Urocortin, a novel peptide activating both types of CRF receptors in vitro, but with preferential affinity for CRF2 receptors in vivo, produced seizures with a lower potency than CRF. These limbic seizures, indistinguishable from those induced by CRF, were abolished by pretreatment with NBI 27914, consistent with their dependence on CRF1 activation. In summary, CRF induces limbic seizures in the immature rat, which are abolished by selective blocking of the CRF1 receptor. CRF1-messenger RNA levels are maximal in sites of seizure origin and propagation during the age when CRF is most potent as a convulsant. Taken together, these facts strongly support the role of the developmentally regulated CRF1 receptor in mediating the convulsant effects of CRF in the developing brain. PMID- 9372208 TI - Parametric survival analysis for gating kinetics of single potassium channels. AB - The gating mechanism and the role of the S4 region in the activation of Shaker potassium channel was studied by statistical analysis on the wild type and mutant channels which have mutations in the S4 region. Single channel currents were recorded with the patch-clamp technique. The first latency time was analyzed with a parametric survival time regression model in which the generalized gamma distribution for the error term was assumed. Discrimination among Weibull, gamma, log-normal and exponential distributions was done with the likelihood ratio test. The three-parameter generalized gamma distribution was shown to be appropriate for the data set. The multiple regression function provides the statistical tests and the quantitative descriptions for the relationships between the mutations and the voltage dependence of the gating process. These results on statistical relations support the hypothesis that the S4 region plays an important role in sensing transmembrane voltage in the gating process, but the gating mechanism is not solely accounted for by the electrostatic interaction between the charged amino acids and the transmembrane voltage field. This work demonstrates that the survival analysis procedures can be useful tools for analyzing neurophysiological signals. PMID- 9372209 TI - Identification of retinal ganglion cells projecting to the lateral hypothalamic area of the rat. AB - The objective of the present study was to identify the retinal ganglion cells projecting to the lateral hypothalamic area of the rat. The retinohypothalamic tract has been divided into a medial and a lateral component on anatomical and developmental grounds. The medial component projects to the suprachiasmatic nucleus and adjacent structures such as the anterior hypothalamic and retrochiasmatic areas. The lateral component terminates in the lateral hypothalamic are dorsal to the supraoptic nucleus. Injections of the retrograde tracer FluoroGold were made into the retinorecipient region of the lateral hypothalamic area and retinal whole mounts were immunohistochemically processed for retrogradely labeled retinal ganglion cells. With FluoroGold injections confined to the lateral hypothalamic area, retrogradely labeled retinal ganglion cells are located almost exclusively in the superior temporal quadrant of the retina. Their size and morphology indicates that they are a homogeneous subset of type III cells, but a definitive classification would require a more complete fill of dendritic arbors than is available in our retrograde material. In contrast, injections involving fibers of passage in the optic tract, or centered in the medial terminal nucleus of the accessory optic system, label cells distributed across the entire retinal surface. Unlike the retinal ganglion cells projecting to the suprachiasmatic nucleus [Moore et al., J. Comp. Neurol., 352 (1995) 351-366], the cells labeled after restricted lateral hypothalamic injections are not distributed evenly across the retinal surface. The difference in location of the retinal ganglion cells projecting to the lateral hypothalamic area supports the view that this retinohypothalamic projection is anatomically and functionally distinct from the projection to the suprachiasmatic nucleus and adjacent medial hypothalamus. PMID- 9372210 TI - Zonisamide as a neuroprotective agent in an adult gerbil model of global forebrain ischemia: a histological, in vivo microdialysis and behavioral study. AB - Brief periods of global cerebral ischemia are known to produce characteristic patterns of neuronal injury both in human studies and in experimental animal models. Ischemic damage to vulnerable areas such as the CA1 sector of the hippocampus is thought to result from excitotoxic amino acid neurotransmission. The objective of this study was to determine the ability of a novel sodium channel blocking compound, zonisamide, to reduce neuronal damage by preventing the ischemia-associated accumulation of extracellular glutamate. Using a gerbil model, animals were subjected to 5 min ischemic insults. Both pre- and post ischemic drug administration (zonisamide 150 mg/kg) were studied. Histological brain sections were prepared using a silver stain at 7 and 28 days post ischemia. The animals sacrificed at 28 days also underwent behavioral testing using a modified Morris water maze. In vivo microdialysis was performed on a separate group of animals in order to determine the patterns of ischemia-induced glutamate accumulation in the CA1 sector of the hippocampus. Pyramidal cell damage scores in the CA1 region of the hippocampus were significantly reduced in animals pre treated with zonisamide compared to saline-treated controls, both at 7 days (drug pre-treated: 0.812 +/- 0.28, n = 8; controls: 1.625 +/- 0.24, n = 8; *P < 0.05) and 28 (drug pre-treated: 0.833 +/- 0.22, n = 12; controls: 1.955 +/- 0.26, n = 11; **P < 0.01) days post ischemia. However, animals receiving zonisamide post treatment did not display significant differences from controls. Behavioral studies also showed significant preservation of function in drug-treated animals. Microdialysis studies confirmed a reduction in glutamate release in drug-treated animals compared to saline-treated controls. Our data suggest that zonisamide is effective in reducing neuronal damage by a mechanism involving decreased ischemia induced extracellular glutamate accumulation and interruption of excitotoxic pathways. PMID- 9372211 TI - Astrocyte-mediated enhancement of neuronal survival is abolished by glutathione deficiency. AB - Astrocytes promote the survival of neurons. Conditions characterized by loss of neurons, such as aging and aging-related neurodegenerative disorders, are accompanied by both disturbances in astrocyte-neuron interactions and signs of oxidative damage. Neuronal glutathione, a major antioxidant in the brain, is maintained by astrocytes and brain levels of glutathione are reduced in named conditions. Therefore, we focused on a possible link between glutathione deficiency and loss of astrocyte-derived neuronal support. For this purpose, we used a coculture system consisting of rat striatal astrocytes and mesencephalic, dopaminergic (DAergic) neurons. Using tyrosine hydroxylase immunocytochemistry and radiolabeled dopamine uptake as parameters, an increase in the number and outgrowth of DAergic neurons was noted in cocultures as compared to cultures of mesencephalic neurons alone. This enhanced survival of DAergic neurons in cocultures was abolished following depletion of glutathione with buthionine sulfoximine. As demonstrated by glial fibrillary acidic protein immunocytochemistry and a microtiter tetrazolium assay, under these conditions no change in astrocyte survival occurred. However, glutathione depletion in cocultures was accompanied by loss of astrocyte-mediated neuroprotection against hydrogen peroxide toxicity. Thus, our results indicate that glutathione is important for the maintenance of the neuronal support function of astrocytes and that glutathione deficiency in the brain may lead to enhanced vulnerability of neurons to (oxidative) damage. PMID- 9372212 TI - Photopigments and photoentrainment in the Syrian golden hamster. AB - The Syrian golden hamster (Mesocricetus auratus) is an important model in the study of circadian rhythms. However, as in other mammals, little is known about the photoreceptors that mediate circadian entrainment. Using immunocytochemistry and RNA blot hybridization, we found no evidence for the presence of blue-/UV sensitive opsin. In contrast, green-sensitive cone opsin was demonstrated in the retina both by immunocytochemistry and reverse-transcription PCR. When used as a probe in RNA blot hybridization, this PCR fragment labelled one transcript (5.8 kb) in hamster retinal RNA. These findings are in accordance with preliminary data from other investigators using electroretinography, which showed one cone mediated photoreceptive mechanism with a maximum sensitivity of 501 nm, but none at shorter wavelengths. However, we found that non-saturating pulses of ultraviolet radiation (357 nm) caused phase shifts in locomotor behaviour. These results corroborate earlier reports that UV radiation can regulate the photoperiodic response in this animal. Having confirmed these apparently contradictory earlier reports, we discuss the mechanisms that might create a UV triggered non-visual response in a green cone monochromat. Finally, we propose the use of the Syrian golden hamster as a model for photoreceptor development and function in the absence of S/UV cones. PMID- 9372213 TI - Basic fibroblast growth factor- and platelet-derived growth factor-mediated cell proliferation in B104 neuroblastoma cells: effect of ethanol on cell cycle kinetics. AB - In vivo studies show (a) that early exposure to ethanol depletes neurons in the central nervous system (CNS) and (b) that a primary target of ethanol in the developing nervous system is proliferating neuronal precursors. We used a neuronal cell line (B 104 neuroblastoma cells) as an in vitro model for the effects of ethanol on the proliferation of neuronal precursors to test the hypothesis that ethanol interferes with growth factor-regulated proliferation of neuron-like precursors. The effects of ethanol on the mitogenic activity of two growth factors, basic fibroblast growth factor (bFGF) and platelet-derived growth factor AA and BB (PDGF-AA and PDGF-BB), were examined. Cell proliferation was monitored by tracing the change in the numbers of cultured cells over 4-5 days and in the cell cycle kinetics was determined using a cumulative labeling technique with bromodeoxyuridine (BrdU). Western immunoblots and immunohistochemical preparations show that B104 cells expressed the high affinity receptors for bFGF, PDGF-AA and PDGF-BB. The three growth factors were potent mitogens for the B104 cells; they promoted an increase in cell number even when the cells were grown in serum-free medium. Ethanol depressed the bFGF-, PDGF-AA- and PDGF-BB-mediated cell proliferation without altering the incidence of cell death. These changes in proliferation were concentration-dependent; at a concentration of 100 mg/dl, ethanol partially, but significantly inhibited growth factor-stimulated proliferation and higher ethanol concentrations (400 mg/dl or more) completely abolished growth factor-regulated cell proliferation. The effects of ethanol on cell growth were a result of ethanol-induced changes in growth factor-regulated cell cycle kinetics, principally the total length of the cell cycle and the fraction of the population that was actively cycling (the growth fraction). Ethanol completely negated the action of bFGF, but only partially blocked PDGF-promoted cycling activity. Thus, B104 cells are a suitable model for studying the effects of ethanol on neuronal proliferation. The blockage of bFGF- and PDGF-mediated cell proliferation by ethanol supports the hypothesis that growth factors are a target of ethanol neurotoxicity. Furthermore, the differential actions and effects of ethanol on the two growth factors mirror effects observed in vivo. PMID- 9372215 TI - Overexpression of superoxide dismutase and catalase in immortalized neural cells: toxic effects of hydrogen peroxide. AB - Hydrogen peroxide (H2O2) is a known toxicant which causes its damage via the production of hydroxyl radicals. It has been reported to cause both necrotic and apoptotic cell death. The present study was undertaken to evaluate the mode of H2O2-induced cell death and to assess if overexpression of catalase could protect against its toxicity. H2O2 causes cell death of immortalized CSM 14.1 neural cells in a dose-dependent manner. H2O2-induced death was associated with DNA laddering as shown by agarose gel electrophoresis. Stable overexpression of catalase by transfection of a vector containing human cDNA into these cells markedly attenuated H2O2-induced toxic effects. Transfection of a vector containing a SOD cDNA afforded no protection. These results indicate that H2O2 can lead to the activation of endonuclease enzyme that breaks DNA into oligosomes. These cells which overexpress catalase or SOD will help to determine the specific role of H2O2 or O2- in the deleterious effects of a number of toxins. PMID- 9372214 TI - Region-specific immediate-early gene expression following the administration of corticotropin-releasing hormone in virgin and lactating rats. AB - Central administration of corticotropin-releasing hormone (CRH) induces immediate early gene (IEG) expression (c-fos and NGFI-B) in forebrain structures in a pattern similar to that observed following restraint stress. Lactating rats display modified neuroendocrine and behavioural responses to stress which have been hypothesized to be at least partially mediated through changes within the circuitry converging on the PVN, including CRH activated pathways. Quantitative measures of regional expression of c-fos and NGFI-B mRNA representative of two classical intracellular pathways, were used to define modification of the circuitry involved in the altered response to central CRH in the lactating female. Compared to saline controls, virgin female rats injected with 5 micrograms CRH i.c.v. displayed significantly increased immediate-early gene expression in the hypothalamic paraventricular nucleus (PVN), arcuate nucleus, lateral septum, bed nucleus of the stria terminalis, central, medial and cortical nuclei of the amygdala, and all subfields of the hippocampal formation. In lactating rats treated with CRH there was a significant increase in c-fos gene expression in the CeA and in the hippocampal subfields CA1, CA4 and dentate gyrus but not in the other areas examined. The i.c.v. administration of CRH significantly increased NGFI-B expression in the PVN, arcuate nucleus, medial amygdala and all hippocampal subfields of virgin rats. Lactating rats treated with CRH failed to show a significant increase in NGFI-B expression in the PVN, median eminence, arcuate nucleus, medial amygdala, CA2 and CA3 subfields of the hippocampus. These results further suggest that changes in specific neural circuits might at least partially underlie the modified responses to CRH and perhaps to stress in the lactating female. PMID- 9372216 TI - Cocaine depresses GABAA current of hippocampal neurons. AB - Although blockade of dopamine re-uptake and the resulting elevation of excitatory agonists is commonly thought the primary mechanism of cocaine-induced seizures, it is possible that other neurotransmitters such as gamma-aminobutyric acid (GABA) are involved. To examine this possibility, the effects of cocaine on the whole cell GABA current (IGABA) of freshly isolated rat hippocampal neurons were investigated with the patch-clamp technique. Preincubation or acute application of cocaine reversibly suppressed IGABA. The IC50 was 127 microM when cocaine was applied before the application of GABA. The concentration-response relations of cocaine in various GABA concentrations revealed that cocaine inhibited IGABA non competitively. This effect of cocaine appeared to be independent of voltage. The present study suggests that the GABA receptor/channel complex is also a target for cocaine's action. The suppression of IGABA may contribute to cocaine-induced seizures. PMID- 9372217 TI - Dopamine receptor-mediated regulation of expression of Fos and its related antigens (FRA) in somatostatin neurons in the hypothalamic periventricular nucleus. AB - Somatostatin (SS)-containing perikarya located within the hypothalamic periventricular nucleus (PeVN) comprise a heterogenous population of neurons with both local intrahypothalamic and distant extrahypothalamic axonal projection sites. The close proximity of SS perikarya and their dendrites to dopaminergic (DA) neuronal processes in the PeVN suggests that these peptidergic neurons may be regulated by DA receptor-mediated mechanisms. To test this, the effects of the D1 agonist SKF 38393 and D2/3 agonist quinelorane were examined on expression of the immediate early gene products Fos and its related antigens (FRA) in SS immunoreactive (IR) neurons in the PeVN. SS-IR neurons were located in the most medial portion of the PeVN bordered medially by the third ventricle and laterally by tyrosine hydroxylase (TH)-IR neurons. In control rats, 10-15% of all SS-IR neurons contained FRA-IR. Activation of D1 receptors with SKF 38393 had no effect on either the total number of SS-IR neurons or the number of SS-IR neurons containing FRA-IR. In contrast, activation of D2/3 receptors with quinelorane decreased the number of SS-IR neurons containing FRA-IR, without affecting the total number of SS-IR neurons. The D2/3 antagonist raclopride had no effect per se, but prevented the quinelorane-induced decrease in the number of SS neurons expressing FRA-IR. These results reveal that activation of D2/3 (but not D1) receptors inhibits expression of the immediate early gene products FRA in SS containing neurons in the PeVN, but expression of FRA in SS neurons is not tonically inhibited by dopamine acting on D2/3 receptors. PMID- 9372218 TI - Soluble tumor necrosis factor receptor (p75) does not attenuate the sleep changes induced by lipopolysaccharide in the rat during the dark period. AB - Sleep is generally enhanced during the early phase of infection. The cytokine tumor necrosis factor (TNF) has been postulated to play an important role in the acute phase sleep response. After demonstrating the ability of a soluble p75 TNF receptor (TNFR) to inhibit TNF activity in vitro, we assessed the influence of TNFR on the sleep changes evoked by lipopolysaccharide (LPS). In this vehicle controlled experiment, 24 rats received either an intracerebroventricular injection of 10 micrograms TNFR, an intraperitoneal injection of 30 micrograms/kg LPS, or both, at the beginning of the dark period. EEG, EMG and brain temperature (Tbr) were recorded during the first 12 h post injection. Compared with vehicle, LPS had minimal effects on Tbr, but promoted non-rapid eye movement sleep (non REMS), suppressed REMS, shortened the sleep episodes and decreased high-frequency (> or = 8 Hz) EEG activity during non-REMS. TNFR alone had no significant effects and did not attenuate any of the LPS-induced sleep changes. These results may either indicate that TNF is not critically involved in the sleep response to a low level LPS challenge during the activity phase or that the soluble p75 TNFR does not effectively antagonize the sleep changes evoked by TNF. PMID- 9372219 TI - Forebrain activation in REM sleep: an FDG PET study. AB - Rapid eye movement (REM) sleep is a behavioral state characterized by cerebral cortical activation with dreaming as an associated behavior. The brainstem mechanisms involved in the generation of REM sleep are well-known, but the forebrain mechanisms that might distinguish it from waking are not well understood. We report here a positron emission tomography (PET) study of regional cerebral glucose utilization in the human forebrain during REM sleep in comparison to waking in six healthy adult females using the 18F-deoxyglucose method. In REM sleep, there is relative activation, shown by increased glucose utilization, in phylogenetically old limbic and paralimbic regions which include the lateral hypothalamic area, amygdaloid complex, septal-ventral striatal areas, and infralimbic, prelimbic, orbitofrontal, cingulate, entorhinal and insular cortices. The largest area of activation is a bilateral, confluent paramedian zone which extends from the septal area into ventral striatum, infralimbic, prelimbic, orbitofrontal and anterior cingulate cortex. There are only small and scattered areas of apparent deactivation. These data suggest that an important function of REM sleep is the integration of neocortical function with basal forebrain-hypothalamic motivational and reward mechanisms. This is in accordance with views that alterations in REM sleep in psychiatric disorders, such as depression, may reflect dysregulation in limbic and paralimbic structures. PMID- 9372220 TI - Pre- and postsynaptic modulation of spinal GABAergic neurotransmission by the neurosteroid, 5 beta-pregnan-3 alpha-ol-20-one. AB - The neuroactive steroid 5 beta-pregnan-3 alpha-ol-20-one (5 beta 3 alpha) modulates GABAA receptor function by potentiating postsynaptic GABA currents. While much is now known about the postsynaptic action of neurosteroids, far less is known about how they affect neurotransmission. We have investigated the synaptic actions of 5 beta 3 alpha in a simple vertebrate model, the embryo of the clawed toad, Xenopus laevis, in which a known GABAergic pathway, activated by the rostral cement gland, terminates swimming when the animal contacts an obstruction. Cement gland stimulation evokes bicuculline-sensitive inhibitory postsynaptic potentials (IPSPs) in motorneurones that terminate swimming and which are greatly enhanced by the presence of (1-5 microM) 5 beta 3 alpha. In the presence of TTX, depolarising inhibitory potentials are recorded with KCl-filled microelectrodes reflecting the spontaneous release of transmitter. The majority are glycinergic with durations of 20-80 ms and are blocked by strychnine while the remainder are GABAergic with durations of 90-200 ms and are abolished by bicuculline. We show here that, in the presence of 5 beta 3 alpha, the spontaneous GABA IPSPs lengthen dramatically in some cases to over 500 ms, but the glycine potentials are unaffected. The steroid has no other detectable postsynaptic effects in that the range of amplitudes of GABA potentials is unaffected and there is no change in the resting membrane potential. However, 5 beta 3 alpha also caused a marked increase in the rate of occurrence of spontaneous GABA potentials. This suggests a novel presynaptic site of action in which the steroid enhances the probability of vesicular GABA release from GABA terminals. PMID- 9372221 TI - Reciprocal connection between nucleus ambiguus and caudal ventrolateral medulla. AB - To investigate interactions between parasympathetic preganglionic neurons in the nucleus ambiguus (NA) and sympathoinhibitory neurons in the caudal ventrolateral medulla (CVLM) the activity of CVLM neurons was recorded during glutamate stimulation of cardioinhibitory sites in the NA of urethane-anesthetized rats. Neurons in the CVLM were identified as cardiovascular neurons if they increased their activity after i.v. phenylephrine and displayed cardiac cycle-related rhythmicity. Of 23 cardiovascular neurons studied, 10 decreased activity after glutamate (GLU) microinjection in the NA, five neurons were excited and eight did not respond. In another series of experiments, the nature of the influence of the CVLM on unit activity in the NA was investigated. Sites in the CVLM from which decreases in arterial pressure and heart rate were elicited after GLU microinjection were identified and the activity of cardiovascular neurons in the NA was recorded. Of 22 NA cardiovascular neurons studied, eight decreased activity after microinjection of GLU in the CVLM and 14 did not change firing frequency. These results demonstrate the existence of a reciprocal pathway between the NA and CVLM and provide evidence for functional interactions between medullary sites implicated in the control of the parasympathetic and sympathetic nervous systems. PMID- 9372222 TI - Seizure patterns in kindling and cortical stimulation models of experimental epilepsy. AB - A large number of animal models has been proposed for the evaluation of the anticonvulsant effect of antiepileptic drugs. Various seizure patterns are produced and differences are frequently observed in anticonvulsant effect estimates obtained for the same drug in different models. The incidence of seizures and the threshold for the induction are usually the only measures used for the determination of the anticonvulsant effect. However, behavioural components expressed during seizures induced by different means are likely to differ considerably. The aim of this study was to provide a detailed behavioural description of ictal and post-ictal components in two models of electrically induced seizure activity: kindling and cortical stimulation model (CSM). Seizure activity was induced in two groups of 6 Wistar-derived rats. Ictal and post-ictal behaviours were recorded on video tape and quantified using a computer supported frame-by-frame encoding of the behavioural components. We encoded the duration and rate of occurrence of the following behavioural items: whisker movements, eye closure, myoclonic jerk, facial gasping, forelimb clonus, forelimb tonus, hindlimb tonus, immobility and chewing. It appears that both models are, in many respects, qualitatively similar. However, the models differ quantitatively. Behavioural expression of seizure activity differs in the following respects: (1) the total duration of the seizure induced by cortical stimulation is shorter than by kindling; (2) seizure activity in the CSM occurs mainly during stimulation, while in amygdala kindling, it occurs thereafter; and (3) seizures evoked in the CSM comprise relatively less violent behavioural items than in the amygdala kindling. The evaluation of the ictal and post-ictal behavioural components suggests that behavioural analysis could assist in the detection of differences in the mechanisms of action of antiepileptic drugs. In addition, observational measures can also be used to assess animal distress inflicted by different experimental procedures. PMID- 9372223 TI - Fos-like immunoreactivity in the circadian timing system of calorie-restricted rats fed at dawn: daily rhythms and light pulse-induced changes. AB - Daily rhythms of pineal melatonin, body temperature, and locomotor activity are synchronized to the light-dark cycle (LD) via a circadian clock located in the suprachiasmatic nuclei (SCN). A timed caloric restriction in rats fed at dawn induces phase-advances and further phase-stabilization of these rhythms, suggesting that the circadian clock can integrate conflicting daily photic and non-photic cues. The present study investigated the daily expression of Fos-like immunoreactivity (Fos-ir) and light pulse-induced Fos-ir in the SCN, the intergeniculate leaflet (IGL) and the paraventricular thalamic nucleus (PVT) in calorie-restricted rats fed 2 h after the onset of light and in controls fed ad libitum. A daily rhythm of Fos-ir in the SCN was confirmed in control rats, with a peak approximately 2 h after lights on. At this time point (i.e. just prior to the feeding time), the level of SCN Fos-ir was lowered in calorie-restricted rats. Concomitantly, IGL Fos-ir was higher in calorie-restricted vs. control rats. In response to a light pulse during darkness, Fos-ir induction was found to be specifically (i.e. phase-dependently) lowered in the SCN and IGL of calorie restricted rats. Observed changes of Fos-ir in the PVT were possibly related to the wake state of the animals. This study shows that repetitive non-photic cues presented in addition to a LD cycle affect the Fos expression in the circadian timing system. PMID- 9372224 TI - Long-term postnatal effect of prenatal irradiation on the astrocyte proliferative response to brain injury. AB - Pregnant Wistar rats were exposed to a single 1.0 Gy dose of gamma-irradiation on gestational day 13, 15, 17 or 19. Thirty-day-old male offspring received a mechanical lesion in the left cerebral hemisphere. One, 2 or 4 days after the injury the rats were injected with [3H]thymidine and sacrificed 4 h after the injection. Thereafter, brain sections were immunostained for GFAP or S100 beta protein, subjected to autoradiography and examined microscopically to record immunopositive astrocytes labelled with [3H]thymidine. Statistically significant elevation of the reactive astrocyte proliferation was revealed on the 2nd day following injury in brains irradiated on gestational day 15. The results represent the first in vivo evidence that a low-dose prenatal gamma-irradiation can induce a long-term increase in the ability of astroglia to proliferate in response to injury. PMID- 9372225 TI - Use of dexamethasone with TTX block of nerve conduction shows that muscle membrane properties are fully controlled by evoked activity. AB - This paper provides further evidence that motorneurons control extrajunctional properties of skeletal muscles through the activity evoked in the muscle fibres. The experiments compare the amount of action potential resistance to tetrodotoxin (TTX resistance) in denervated soleus muscle with that in soleus whose nerve was crushed and then allowed to regenerate in the presence of a block of the sciatic impulse conduction. Measurements were taken after about 2-3 weeks to allow full reinnervation and recovery of trophic regulation by the nerve. Blocking sciatic impulse conduction with TTX solutions containing low doses of the anti inflammatory drug dexamethasone induced values of extrajunctional TTX resistance identical to those caused by denervation. In contrast lower levels of TTX resistance were obtained with dexamethasone-free solutions or when the drug was administered through the systemic path rather than topically applied to the nerve. These results indicate that physiological neural regulatory signals other than activity do not participate to the regulation of extrajunctional properties of skeletal muscles. Furthermore the low levels of TTX resistance measured with dexamethasone-free blocks confirm our previous experiments indicating that reported differences between denervation and pure inactivity are attributable to incomplete suppression of nerve impulse conduction. PMID- 9372226 TI - Intraintestinal capsaicin transiently reduces CGRP-like immunoreactivity in rat submucosal plexus. AB - Intraintestinal infusion of the sensory neurotoxin, capsaicin, transiently abolishes behavioral responses to chemical stimulation of the intestine. This desensitizing action of capsaicin may be due to an action on CGRP-containing nerve terminals, which are postulated to serve a sensory function in the enteric plexuses. To determine whether intraintestinal capsaicin treatment alters CGRP like immunoreactivity (CGRP-li) in the enteric plexuses, we performed immunohistochemical analyses of the small intestinal submucosal and myenteric plexuses of rats at various times after intestinal infusion of capsaicin (5 mg) or its vehicle. Intestinal capsaicin treatment, but not vehicle treatment, reduced CGRP-li, but not substance-P-like immunoreactivity (SP-li), in nerve fibers of the submucosal plexus. CGRP-li was reduced in submucosal interganglionic connectives and in nerve fibers associated with submucosal blood vessels. CGRP-li of submucosal connectives was reduced by 1 h post-infusion. Reduction of CGRP-li in the submucosal fibers also was pronounced 24 h after intraintestinal capsaicin treatment. By 48 h after intestinal capsaicin infusion, CGRP-li was not distinguishable from vehicle-treated animals. There were no consistent immunohistochemical changes in CGRP-li or SP-li in the myenteric plexus at any time. These results indicate that intestinal capsaicin selectively induces transient reduction of CGRP-li in nerve fibers of the submucosal plexus. The chronology of depletion and reappearance of CGRP-li is congruent with previously reported, transient impairment of sensory function observed following intestinal capsaicin infusion. PMID- 9372227 TI - Currents evoked by GABA and glycine in acutely dissociated neurons from the rat medial preoptic nucleus. AB - The responses of acutely dissociated medial preoptic neurons to application of GABA, and glycine were studied using the perforated-patch whole-cell recording technique under voltage-clamp conditions. GABA, at a concentration of 1 mM, evoked outward currents in all cells (n = 33) when studied at potentials positive to -80 mV. The I-V relation was roughly linear. The currents evoked by GABA were partially blocked by 25-75 microM picrotoxin and were also partially or completely blocked by 100-200 microM bicuculline. Glycine, at a concentration of 1 mM, did also evoke outward currents in all cells (n = 12) when studied at potentials positive to -75 mV. The I-V relation was roughly linear. The currents evoked by glycine were largely blocked by 1 microM strychnine. In conclusion, the present work demonstrates that neurons from the medial preoptic nucleus of rat directly respond to the inhibitory transmitters GABA and glycine with currents that can be attributed to GABAA receptors and glycine receptors respectively. PMID- 9372228 TI - Autoradiographic studies of central alpha 2A- and alpha 2C-adrenoceptors in the rat using [3H]MK912 and subtype-selective drugs. AB - In the present study we examined the distribution of alpha 2A- and alpha 2C adrenoceptors in tissue slices from the rat cervical spinal cord and from brain slices collected at the level of the striatum. To differentiate between alpha 2A- and alpha 2C-adrenoceptors, the slices were incubated with [3H]MK912 in the presence of graded concentrations of the alpha 2A-selective drug, BRL44408, or the alpha 2C-selective drug, spiroxatrine. Computer analysis of the autoradiograms indicated that 0.4 nM [3H]MK912 plus 185 nM BRL44408 selectively labeled alpha 2C-adrenoceptors, while 0.4 nM [3H]MK912 plus 220 nM spiroxatrine selectively labeled alpha 2A-adrenoceptors. Using this approach, alpha 2C adrenoceptors were detected in the striatum, while alpha 2A-adrenoceptors predominated in the cortical layers 1-4, the spinal cord distal dorsal horn, the septum and the endopiriform nucleus. PMID- 9372229 TI - Luteinizing hormone-releasing hormone gene expression differs in young and middle aged females on the day of a steroid-induced LH surge. AB - LHRH mRNA levels were examined in young and middle-aged female rats at 4 times (10:00 h, 14:00 h, 18:00 h and 20:00 h) on the day of a steroid-induced LH surge by in situ hybridization with a digoxigenin-labeled riboprobe. Young, but not middle-aged females, exhibited dynamic temporal changes in the number of LHRH mRNA positive neurons detected in the organum vasculosum of the lamina terminalis preoptic area (OVLT-POA) continuum. Specifically, fewer LHRH mRNA positive neurons were detected at 18:00 h compared with the number detected at 14:00 h and 20:00 h (P < 0.01) in the OVLT-POA of young females. All LHRH mRNA positive neurons present in 4 anatomically matched sections through the rostral POA of young and middle-aged animals were digitized for detailed computer-assisted analysis of the hybridization reaction product. The mean hybridization area (P < 0.00025) and integrated optical density per cell (P < 0.006) were reduced in middle-aged compared to young females consistent with a relative age-related decline in LHRH mRNA levels. Moreover, an age-related reduction in cellular and/or regional hybridization area was noted at each of the time points examined (P < 0.05-P < 0.001). These data confirm earlier reports of dynamic changes in LHRH mRNA levels on the day of an LH surge. Furthermore, they support a role for age-related alterations in LHRH gene expression in the disruption of regular estrous cyclicity in middle-aged females. PMID- 9372230 TI - Peripheral administration of cholecystokinin activates c-fos expression in the locus coeruleus/subcoeruleus nucleus, dorsal vagal complex and paraventricular nucleus via capsaicin-sensitive vagal afferents and CCK-A receptors in the rat. AB - Intraperitoneal (i.p.) administration of sulfated CCK octapeptide (CCK-8S) has been shown to induce changes in neuronal activity in the nucleus of the solitary tract (NTS) and area postrema (AP), sensory parts of the dorsal vagal complex (DVC), and in the paraventricular nucleus of the hypothalamus (PVN), as determined by activation of c-fos expression. Whether peripheral CCK influences neuronal activity in the locus coeruleus (LC)/subcoeruleus nucleus (SC) was investigated in awake rats at intraperitoneal (i.p.) injection of CCK-8S by c-Fos immunohistochemistry. CCK-8S i.p. (25, 50, and 100 micrograms/kg, respectively) dose-dependently increased the average number of c-Fos-LI-positive cells/section in the LC/SC by the factor 5.9, 8.2, and 11.7, respectively. Pretreatment with the CCK-A receptor antagonist MK-329 (devazepide; 1 mg/kg and 2 mg/kg i.p.) reduced the CCK-induced increase in c-fos expression in the LC/SC by 54% and 75%, respectively; the CCK-B receptor antagonist L-365,260 had no effect. Perivagal capsaicin pretreatment diminished the CCK-induced increase in the number of c-Fos LI-positive cells in the LC/SC by 65%. In comparison, the CCK-A antagonist devazepide (1 mg/kg and 2 mg/kg i.p.) reduced the increase in c-fos expression by 76% and 88% in the PVN, 69% and 88% in the NTS, 86% and 83%, respectively, in the AP. Capsaicin diminished the CCK-induced increase in c-Fos-LI-positive cells in the PVN by 64%, in the NTS by 60%, but in the AP only by 25%. Immunostaining against the nuclear antigen c-Fos and the cytoplasmatic antigen tyrosine hydroxylase (TH) showed that 40% of all c-Fos-LI-positive cells in the LC/SC were TH-LI positive at 25 micrograms CCK/kg. The data indicate that CCK-8S i.p. induces modulation of neuronal activity in the LC/SC, DVC and PVN predominantly by peripheral action of CCK-A receptors and capsaicin-sensitive vagal afferents. These findings suggest that the LC/SC is involved in CNS-mediated regulatory influences of peripheral CCK. PMID- 9372232 TI - Coexpression of calretinin and parvalbumin in Ruffini-like endings in the rat incisor periodontal ligament. AB - The coexpression of calretinin- (CR) and parvalbumin-immunoreactivities (irs) was examined in oro-facial tissues of the rat. Nerve fibers coexpressing these calcium-binding proteins (CaBPs) were observed in the lingual periodontal ligament of incisors but not other tissues. In the part of periodontal ligament adjacent to the alveolar bone, such nerve fibers left nerve bundles and formed bush-like endings, i.e., they ramified repeatedly and terminated with one to four twigs. An immunoelectron microscopic method indicated that these endings were identical to Ruffini-like endings, 4% of trigeminal neurons retrogradely labeled from the inferior alveolar nerve coexpressed CR- and parvalbumin-irs. The present observations suggest that the coexpression of these CaBPs may be a specific marker for low-threshold mechanoreceptors in the trigeminal ganglion. PMID- 9372231 TI - Induction of metallothionein-I (MT-I) mRNA in primary astrocyte cultures is mediated by hypotonicity and not ethanol (EtOH) per se. AB - Metallothionein (MT) mRNA was determined in rat astrocyte cultures in response to ethanol (EtOH). MT-I mRNA was significantly increased after 6 h exposure to isosmotic EtOH, but not hyperosmotic EtOH. Exposure to a hyposmotic/hypotonic solution also led to a significant increase in the expression of astrocytic MT-I mRNA. The large increase in MT-I mRNA was not due to removal of extracellular NaCl, because this effect was reversed by replacement of NaCl with N-methyl D glucamine chloride. A significant decrease in MT-I mRNA was also noted in astrocytes exposed to an EtOH-free hyperosmotic/hypertonic solution. These results suggest (1) that EtOH per se does not directly induce MT-I mRNA expression, (2) that the induction by EtOH of MT-I mRNA is secondary to hypotonicity, and (3) that hyperosmotic/hypertonic exposure is associated with reduced expression of MT-I mRNA in astrocyte cultures. PMID- 9372233 TI - Effects of a nitric oxide synthase inhibitor on NMDA receptor function in organotypic hippocampal cultures. AB - Nitric oxide (NO) has been proposed to trigger long-term potentiation (LTP) at CA3 to CA1 synapses. We previously reported that NO synthesis inhibitors and blockers reduce an electrophysiological index of NMDA receptor activation in acute hippocampal slices. We now show that the NOS inhibitor, NG-methyl-L arginine (MLA), also reversibly prevents LTP induction in organotypic hippocampal slices and significantly reduces a biochemical index of NMDA receptor function. These results results further indicate that MLA inhibits LTP induction by interfering with NMDA receptor functions. PMID- 9372234 TI - Entorhinal cortex lesioning protects hippocampal CA3 neurons from stress-induced damage. AB - The role of the entorhinal cortex (EC) in stress-induced damage in terms of dendritic branching points and intersections of hippocampal CA3 neurons has been investigated. Following bilateral electrolytic lesions of the EC, the rats were subjected to restraint stress, 6 h per day for 21 days. Chronic restraint stress resulted in the atrophy of hippocampal CA3 neurons and the lesioning of the EC prior to stress significantly (P < 0.001) reduced this dendritic atrophy. These results show that the neuronal vulnerability to chronic stress can be attenuated by entorhinal glutamatergic denervation. PMID- 9372235 TI - Detection of Borna disease virus genome in normal human brain tissue. AB - Borna disease virus (BDV), a neurotropic virus naturally infecting horses and sheep, has been suggested to be associated with human psychiatric disorders. Thus far no extensive studies have been done, providing the evidence of BDV genome in normal human brain tissue. We therefore examined four brain regions of 30 normal autopsy brains for BDV p24 genome. By highly sensitive nested reverse transcriptase (RT)-mediated PCR analysis, we found positive PCR products in two brains: one in frontal and temporal cortices and hippocampus and another in frontal cortex and olfactory bulb. Our results suggest that BDV can infect human brain tissue latently, without causing an apparent neuropsychiatric disorder. PMID- 9372236 TI - Spinalization increases the mechanical stimulation-induced withdrawal reflex threshold after a sciatic cut in the rat. AB - The purpose of the present study was to establish whether supraspinal structures modulate mechanical 'adjacent hyperalgesia'. After a chronic sciatic cut, the paw withdrawal threshold to mechanical stimulation was lower, and the latency of noxious radiant heat-induced withdrawal reflex was shorter at the traumatized side than at the intact side. Then the rats were spinalized, and the withdrawal threshold to mechanical stimulus increased at the injured side, but the withdrawal latency induced by noxious heat decreased at the intact side. No side differences between the injured and the intact side could be detected after spinalization. Thus supraspinal structures may participate in maintenance of mechanically evoked paw withdrawal reflex after a sciatic injury. PMID- 9372238 TI - Inactivation of MyoD-mediated expression of p21 in tumor cell lines. AB - The basic helix-loop-helix protein MyoD induces muscle structural gene expression and cell cycle withdrawal in many nontransformed cell lines. We show that MyoD activation of transcription of the cyclin-dependent kinase inhibitor p21 does not require synthesis of an intermediary protein. In most of the rhabdomyosarcoma and other solid tumor cell lines that we analyzed, p21 levels were abnormally low and correlated with the combined inactivity of MyoD and p53, two known transcriptional activators of p21. Loss of MyoD activation of p21 transcription correlated with the failure to arrest in G1, and expression of p21 caused accumulation of cells in G1, further supporting a role for p21 in MyoD-induced cell cycle arrest. Finally, different tumor types have inactivated distinct factors necessary for p21 expression, because p21 expression was reconstituted in hybrid cell lines. We propose that p21 integrates growth-inhibitory signals from independent p53 and basic helix-loop-helix pathways, and that in the majority of tumor cell lines, both pathways are abrogated. PMID- 9372237 TI - Expression of INK4 inhibitors of cyclin D-dependent kinases during mouse brain development. AB - In situ hybridization of mouse embryo sections demonstrated expression of mRNAs encoding two polypeptide inhibitors (p18INK4c and p19INK4d) of cyclin D-dependent kinase (CDK) 4 and CDK6 in the central nervous system. No expression of two other INK4 members, p16INK4a and p15INK4b, was observed. The p19INK4d and p18INK4c proteins formed complexes with either CDK4 or CDK6 in a temporal pattern consistent with the results of in situ hybridization. Expression of INK4c was observed at embryonic day 13.5 in neuroepithelial zones of the developing brain, being restricted to dividing neuroblasts but absent from differentiating postmitotic neurons. In the neocortex, p18INK4c was expressed precisely at those developmental stages when neuroblasts switch from a symmetric to an asymmetric pattern of cell division with concomitant increases in their G1 interval. INK4d RNA was detected from embryonic day 11.5 onward, at higher levels than INK4c and with a distinctly different spatial and temporal pattern. Marked INK4d expression was seen in dorsal root ganglia, spinal cord, and focally throughout the brain, but primarily in postmitotic neurons. Neural expression of INK4d continued postnatally into adulthood in postmitotic cells of the dentate gyrus, the pyramidal layer of the hippocampus, and in discrete regions of the cerebral cortex, cerebellum, thalamus, and brainstem. Downregulation of p19INK4d in the dentate gyrus after kainic acid-induced seizures indicated that its expression could also be modified in nondividing cells by excitotoxic stress. Therefore, p19INK4d may contribute to maintaining the quiescent state, acting as a buffer to prevent reactivation of cyclin D-dependent kinases in terminally differentiated cells. PMID- 9372239 TI - CDC2 is down-regulated by ionizing radiation in a p53-dependent manner. AB - The mammalian cellular response to ionizing radiation results in delays in progression through the cell cycle at several checkpoints and includes alterations in the activity of cyclin-dependent kinases. The product of the CDC2 gene is a key kinase involved in cell cycle progression. The signaling events that regulate its expression after exposure to DNA-damaging agents are not known. We show that cdc2 mRNA and protein are down-regulated after irradiation of normal human and mouse fibroblasts with doses as low as 0.5 Gy. This down-regulation is preceded by induction of p53 and p21Waf1 proteins. In human cells in which p53 was nonfunctional and in p53-/- or p21-/- mouse embryo fibroblasts, no effect of ionizing radiation on p34cdc2 expression levels was observed. These findings indicate that CDC2 down-regulation after irradiation is p53-dependent and involves the cyclin-dependent kinase inhibitor p21Waf1 as a negative factor in the control of CDC2 expression. Correspondence between the delay in initiation of DNA synthesis in irradiated cells and the down-regulation of CDC2 is described. PMID- 9372240 TI - Expression of the SIL gene is correlated with growth induction and cellular proliferation. AB - The SIL gene was discovered at the site of a cancer-associated interstitial deletion in which its promoter assumed the regulation of a second gene, SCL. The human SIL gene encodes a 1287-amino acid cytosolic protein that has been found to be highly conserved in the mouse. SIL is expressed in proliferating cells and is down-regulated when cellular proliferation ceases because of serum starvation, contact inhibition, or induction of terminal differentiation. SIL is induced within 1 h of stimulation by 20% serum in growth-arrested 3T3 cells. This induction is independent of protein synthesis because "superinduction" is observed in the presence of the protein synthesis inhibitor cyclohexamide. Thus, SIL is an immediate-early gene. Upon release from serum starvation of 3T3 fibroblasts, SIL mRNA and protein levels display a biphasic pattern during the first cell cycle. In contrast, in exponentially growing EL4 lymphoblasts, SIL mRNA is stable throughout the cell cycle, whereas SIL protein accumulates into G2 phase and then falls precipitously at the completion of the cell cycle. This pattern of cell cycle expression suggests that SIL may play an important role in cellular growth and proliferation. PMID- 9372242 TI - Diminished tumorigenic phenotype after depletion of mitochondrial DNA. AB - Modulation of tumorigenicity has been considered to be a reflection of the (nuclear) genetic and cellular aberrations present in tumor cells. Recent studies have suggested that cytoplasmic elements can also contribute to the malignant phenotype of cancer, and that mitochondria may be important in this process. We, therefore, undertook a study to evaluate the effects of depletion of functional mitochondria on the tumorigenic phenotype. Brain and breast tumor cells were depleted of mitochondrial DNA [rho(-)] by treatment with ethidium bromide. These rho(-) respiratory-deficient cells showed a distinct change in the tumorigenic phenotype, including loss of ability to grow in an anchorage-independent fashion and, interestingly, a substantial increase in sensitivity to cytotoxic drugs (1,3 bis-chloroethyl-1-nitrosourea and cis-diamminedichloroplatinum(II)). Reversion to the tumorigenic phenotype was accomplished with transfer of normal mitochondria into the diminished tumorigenic rho(-) cells. No changes in expression of the apoptosis genes bcl-2 and bax, nor the drug resistance genes mdr1, mrp, or O6 alkyltransferase was found in any of the cell types (de novo, rho(-), or cybrid). Further, the type of cell death remained the same, i.e., cells with and without mitochondria underwent apoptosis in response to exposure to cytotoxic agents. Our results indicate that mitochondria/mitochondrial DNA play a direct role in modulating aspects of the tumorigenic phenotype, although they are not necessarily a sine qua non for apoptotic cell death. This is particularly interesting because most tumor tissues are more dependent upon glycolysis for energy production, rather than mitochondrially mediated oxidative phosphorylation. Creation of rho(-) cells will be useful to study the mitochondrial processes involved in tumorigenesis. PMID- 9372241 TI - Sustained versus transient cyclic AMP intracellular levels: effect on thyrotropin dependent growth of thyroid cells. AB - Cyclic AMP (cAMP) is the second messenger that stimulates growth and differentiation of thyroid cells, which are dependent upon thyrotropin for the initiation of the cell cycle. Treatment of thyroid cells with phosphodiesterase inhibitors, such as 1-methyl-3-isobutylxanthine (IBMX), RO-20-1724, or aminophylline, induces persistent levels of cAMP and blocks cell proliferation. IBMX-treated cells are arrested at the G1-S border, but removal of the drug allows cell growth to resume. The inhibiting effect of IBMX is dose dependent, and the phase of the cell cycle is irrelevant. These data indicate that prolonged and steady accumulation of cAMP blocks the cell cycle in thyroid cells. PMID- 9372243 TI - Regulation of fibroblast growth factor 2 expression in melanoma cells by the c MYB proto-oncoprotein. AB - Dysregulated expression of basic fibroblast growth factor [fibroblast growth factor 2 (FGF-2)] mediates autocrine growth of melanoma cells. The presence of a consensus Myb binding site in the human FGF-2 promoter prompted us to investigate whether this transcription factor could regulate FGF-2 expression in melanomas. We report that c-MYB mRNA is overexpressed in melanoma cell lines compared to normal melanocytes and that ectopic expression of murine c-Myb in SK-MEL-2 human melanoma cells resulted in increased expression of FGF-2 mRNA and FGF-2 protein. Furthermore, murine c-Myb transactivated a reporter plasmid containing the human FGF-2 promoter region in contransfected SK-MEL-2 human melanoma cells. Although a functional DNA-binding domain was required for transactivation, responsiveness to c-Myb was independent of the putative Myb binding site and mapped to two regions of the FGF-2 promoter that did not bind c-Myb in vitro. We suggest that c-MYB contributes to FGF-2-mediated autocrine growth of melanomas by indirectly regulating the FGF-2 promoter. PMID- 9372244 TI - Transient absence of CD44 expression and delay in development by anti-CD44 treatment during ontogeny: a surrogate of an inducible knockout? AB - Because the lack of some adhesion molecules induced by site-directed mutagenesis has been described to be lethal, whereas the lack of others apparently has no effect, we were interested in seeing whether the developing organism might gradually adapt to the absence of adhesion molecules. Therefore, we chose a form of transient interference by i.v. injection of antibody into pregnant rats. As a model, we selected CD44, which has been reported to play a key role during embryogenesis. Rats received either an antibody recognizing an epitope on the CD44 standard isoform (CD44s) or on exon v6 (CD44v6). In the presence of anti CD44s, delivery was frequently delayed, and intrauterine abortions were often observed. The fetuses were smaller, particularly the anlage of the hair follicle of the whisker, and the formation of alveoli in the lung, of the tubular system of the kidney, and of villi in the gut was delayed. The development of fetuses receiving anti-CD44v6 was hampered until days 16-18 of gestation. Immunodetection revealed a weaker expression of the target molecules at the implantation site and the complete absence of CD44s and CD44v6 expression in fetal tissue until day 12. During the late stages of gestation, the expression pattern of CD44 resembled that of 2-3-day-younger fetuses of untreated rats. Interestingly, degradation of hyaluronate was also delayed, particularly in the kidney. Thus, the diaplacental antibody passage was very efficient and should make it possible to obtain a clearly defined and differentiated concept of the requirements for the CD44 molecule during ontogeny and also for fail-safe mechanisms. Both experiences may be missed in the knockout proper. PMID- 9372246 TI - The wind of change. PMID- 9372245 TI - CGP 41251 and tamoxifen selectively inhibit mitogen-activated protein kinase activation and c-Fos phosphoprotein induction by substance P in human astrocytoma cells. AB - The substance P (SP) receptor (NK-1 subtype) is widely expressed in primary human astrocytomas and glioblastomas and many brain tumor-derived cell lines. SP receptor activation stimulates the mitogen-activated protein (MAP) kinase pathway and the expression of immediate-early genes (e.g., c-Fos and c-Myc), resulting in an increase in DNA synthesis in human astrocytoma U-373 MG cells. In this study, we investigated the role of protein kinase C (PKC) in SP receptor activation of the MAP kinase pathway. SP peptide, epidermal growth factor, and the PKC activator 12-O-tetradecanoylphorbol-13-acetate (TPA) induced the tyrosine phosphorylation of the Erk1 and Erk2 MAP kinases in a concentration-dependent manner in U-373 MG cells. Pretreatment of the cells with PKC inhibitors, CGP 41251 or tamoxifen, inhibited tyrosine phosphorylation of Erk1 and Erk2 MAP kinases induced by low concentrations of SP or TPA and significantly attenuated phosphorylation at high concentrations of SP or TPA. The inhibitory effect exhibited by tamoxifen on SP-induced MAP kinase activation is similar to that exhibited by the selective PKC inhibitor CGP 41251, suggesting that the PKC enzyme is the in situ target for both inhibitors. Furthermore, SP-induced c-Fos phosphoprotein expression is inhibited by CGP 41251 or tamoxifen with similar efficacy. Importantly, neither CGP 41251 nor tamoxifen has any detectable effect on the MAP kinase activation by epidermal growth factor, consistent with the ability of this growth factor to activate the MAP kinase pathway by a PKC independent mechanism. Prolonged treatment with TPA resulted in down-regulation of PKC and selective inhibition of TPA- and SP-induced Erk1 and Erk2 tyrosine phosphorylation in U-373 MG cells. Consistent with the in situ results, CGP 41251 and tamoxifen significantly inhibited endogenous PKC enzymatic activity from U 373 MG cells in vitro. In contrast to CGP 41251 and tamoxifen, Go 6976, a highly selective inhibitor for PKC alpha and PKC beta 1 isozymes, did not inhibit SP- or TPA-induced tyrosine phosphorylation of Erk1 and Erk2 MAP kinases; rather, it inhibited a signaling pathway leading to the phosphorylation of cAMP-responsive element binding protein in U-373 MG cells. To investigate whether selective PKC isozyme(s) are involved in the activation of the MAP kinase pathway by SP, we determined the expression of PKC isozymes in U-373 MG cells. We found that U-373 MG cells express nine different PKC isozymes (alpha, beta I, beta II, epsilon, delta, eta, zeta, iota, and mu) and that stimulation with SP results in significant and selective translocation of PKC epsilon isozyme from cytosolic to membrane fraction. This establishes a correlation between the ability of SP to activate the MAP kinase pathway and its ability to translocate PKC epsilon. In conclusion, the results presented in this study demonstrate that SP receptor activation of PKC, possibly PKC epsilon, leads to the activation of the MAP kinase pathway, and that this pathway can be inhibited by known PKC inhibitors. PMID- 9372247 TI - Otoplasty: techniques, results and complications--a review. PMID- 9372248 TI - Evidence for efferent effects on auditory afferent activity, and their functional relevance. PMID- 9372249 TI - Does socially disturbing snoring and/or excessive daytime sleepiness warrant polysomnography? PMID- 9372250 TI - The magnitude of random errors in acoustic rhinometry and re-interpretation of the acoustic profile. AB - By measuring the effect of incomplete acoustic seal and increasing nosepiece insertion depth on the derived nasal acoustic profile, this study quantifies the random errors that may arise in the course of the clinical practice of acoustic rhinometry using the insert nosepiece. The relative movement of the nose and nosepiece also enables us to separate the contribution of each to the acoustic curve. Sixteen volunteers were tested using a commercial rhinometer. As a consequence of this study we are able to formulate the following conclusions: (1) The first minimum of the nasal acoustic profile is due to the end of the nosepiece, but may be further diminished by the position of the nosepiece tip on or within the nose. (2) The second minimum is due to the nasal valve, to which the head of the inferior turbinate contributes. (3) Acoustic rhinometry is extremely sensitive to acoustic leaks and results obtained without a fluid acoustic sealant cannot be considered valid. (4) The errors associated with the nosepiece insertion technique are very small unless the nosepiece is forced into the nasal vestibule. PMID- 9372251 TI - Characterization of nasal airflow. AB - Nasal airflow and trans-nasal pressure difference was measured by active anterior rhinomanometry in 24 subjects. An analysis was undertaken to determine the 'goodness of fit' of two models used to characterize nasal airflow, one model by Broms and the other by O'Neill and Tolley. A judicious approach to choice of fit criterion led to the conclusion that the latter model provided a more accurate characterization of nasal airflow. Additionally this model may be useful to quantify alar valve stiffness. A portable computerized system incorporating the use of the model has been developed and is currently in use. PMID- 9372252 TI - The relationship between obstructive sleep apnoea and body mass index. AB - Obese patients have a high prevalence of obstructive sleep apnoea (OSA), but a low response rate and high frequency of relapse after uvulopalatopharyngoplasty (UVPP). In this study we have determined the level of obstruction during sleep in 31 men with OSA, using a catheter with multiple micropressure transducers and a portable digital recorder. The proportion of apnoeic episodes with obstruction at lower levels correlated with increasing body mass index (BMI) (P < 0.05). Thus, with increasing obesity, there seems to be a shift to a lower level of obstruction. All patients with BMI > 30 and apnoea index (AI) > 5 had predominantly lower obstructions (P < 0.05). This may explain why many obese patients fail to respond, or have relapses after UVPP. PMID- 9372253 TI - Long-term effects of ventilation tubes for persistent otitis media with effusion in children. AB - The otological, auditory and developmental effects of treatment with ventilation tubes were studied in a sample of 7-8-year-old Dutch children screened for otitis media with effusion (OME) serially at preschool age. Children treated with ventilation tubes were matched retrospectively for OME history, sex, and age with children who were not treated surgically. At the age of 7-8, abnormalities of the tympanic membrane were more prevalent in treated than in untreated ears. No significant differences were found in middle ear function and hearing in both groups. Some positive effects of early surgical intervention on specific developmental measures were found. PMID- 9372254 TI - Long-term use of hearing aids in patients with presbyacusis. AB - The aim of this study was to determine how the use of a hearing aid in presbyacusis varied with the passage of time. A questionnaire survey of patients with presbyacusis who had been fitted with a monaural behind the ear NHS hearing aid for the first time was undertaken. The patients were divided into six groups ranging from 6 months to 5 years after fitting. Overall regular long-term use of the hearing aid was found in the majority of patients with presbyacusis. The main drop-out point was within the first year after fitting the hearing aid. The study furthermore revealed a relatively high demand for further help and advice with the hearing aid in all groups. PMID- 9372255 TI - Adenoid cystic carcinoma of the head and neck. AB - Adenoid cystic carcinoma has a long natural history but frequently proves fatal. The present study describes 108 patients with an adenoid cystic carcinoma of the head and neck seen over a 30-year period. Analysis of the data utilized both univariate and multivariate methods. Forty per cent of patients had tumours arising from the oral cavity and half of these were in the hard palate; 29% occurred in the major salivary glands; 41% of tumours were locally advanced at presentation and 11% had lymph node metastases at this time. The histological pattern was solid in 25%, cribriform in 40% and tubular in 20%. In addition, 15% of patients had a polymorphous low-grade adenocarcinoma and these were analysed separately. Primary site recurrence was more common in the presence of locally advanced tumours at presentation (T3-4) (P = 0.0093). Only six patients had surgery with adjuvant radiotherapy. Six patients had no curative treatment, 21 had primary radiotherapy, 39 had local excision and 42 radical excision. The actuarial primary site recurrence rate was 100% at 30 years. The neck node recurrence rate was 23% at 15 years. Tumour specific survival was 40% at 20 years. Solid histology had a worse prognosis than other histological types (P = 0.0429) but those patients with polymorphous low-grade adenocarcinomas fared very well. Patients with tumours of the hard palate fared better than those patients with tumours at other sites (P = 0.0301). Early disease at the primary site (T1 2) was a good prognostic sign (P = 0.0013). Patients with neck node metastases at presentation tended to do badly (P = 0.009). PMID- 9372256 TI - The influence of alcohol and smoking on the incidence of oral and oropharyngeal cancer in women. AB - A retrospective case reference study examining the use of alcohol and tobacco in 303 women aged 40 or over suffering from oral or oropharyngeal cancer was conducted in the south-west Netherlands. Both alcohol and tobacco consumption are important in the development of oral and oropharyngeal cancer with increased consumption of both markedly increasing the risks of cancer, but alcohol having the greater effect. PMID- 9372257 TI - The evaluation of eustachian tube function in patients with chronic otitis media. AB - In this study we evaluated eustachian tube function in patients with chronic otitis media and compared the results with normal subjects. Two different eustachian tube function tests were applied to 60 ears of the chronic otitis media group and 146 ears of the control group. While eustachian tube dysfunction was observed in 71.7% of the chronic suppurative otitis media group, it was only seen in 34.9% of the control group. PMID- 9372258 TI - A cephalometric analysis of nasal septal growth. AB - In a study using lateral cranial radiographs of 454 males and 475 females (age 0 20 years) the anterior nasal spine-nasion (ANS-N) and ANS-posterior nasal spine (ANS-PNS) distance were measured and related to age and gender. The development of both dimensions is best described by negative exponential functions. ANS-PNS distance to the age of 5 and the ANS-N distance to the age of 2, develop linearly without gender difference. After this, deceleration, statistically more significant in females (P < 0.01, ANCOVA non-linear regression analysis) occurs for both parameters. Although a study of this type does not have maximal sensitivity, no significant calendar-age-related 'growth spurts' were detected. PMID- 9372260 TI - Otitis media with effusion: a disability or not? AB - Otitis media with effusion (OME) is a disease most commonly affecting the paediatric population. However, it is a condition that is also seen in adults and does lead to significant morbidity. We studied the effect of surgical treatment of OME in an adult population and found that the subjective relief of symptoms exceeded the objective audiometric gain. In children where subjective symptoms are perhaps more difficult to assess the clinician needs to beware of underestimating the effect of a hearing loss. PMID- 9372259 TI - Comparing the outcome of two surgical treatments for snoring using a patient orientated measure of benefit. AB - Many different surgical techniques are currently used to treat simple snoring and their outcomes are difficult to compare. We used the Glasgow Benefit Inventory (GBI) to examine the outcome of two different surgical procedures. Thirty patients had been treated by uvulopalatopharyngoplasty (UPPP) and fifty-six by laser palatoplasty. The GBI scores showed close agreement with other subjective outcome measures. The two groups gave similar scores at 15 months postoperatively, and there was no deterioration in score with time. The GBI could be used to evaluate new surgical techniques for snoring, and could be useful in research and audit in this field. PMID- 9372261 TI - Capillary electrophoresis of DNA for molecular diagnostics. AB - A number of applications of capillary zone electrophoresis (CZE) in sieving liquid polymers (notably linear polyacrylamides and cellulose) for the analysis of polymerase chain reaction (PCR) products of clinically relevant, diagnostic DNA, are reviewed. The fields covered are: human genetics, quantitative gene dosage, microbiology and virology, forensic medicine and therapeutic DNA (notably, antisense nucleotides). Some unique, novel developments are highlighted, such as: (i) nonisocratic CZE, i.e., temperature-programmed CZE for detection of DNA point mutations; (ii) the synthesis of novel N-substituted acrylamides, offering extreme resistance to alkaline hydrolysis coupled to high hydrophilicity. In the field of denaturing gradient gel electrophoresis (DGGE), as routinely performed in gel slabs, a novel methodology is described in CZE: double-gradient DGGE. In this technique, two gradients are simultaneously applied along the migration direction: a chemical (or thermal) denaturing gradient, for partially unwinding homo- and hetero-duplexes of DNA, and a porosity gradient, for recompacting diffuse bands melting over a broader range of denaturing conditions. It is thus demonstrated that chemical gradients, in addition to temperature gradients, can be easily implemented even in a capillary format. PMID- 9372262 TI - Capillary electrophoresis as a clinical tool for the analysis of protein in serum and other body fluids. AB - Most electrophoretic analyses of proteins in the clinical laboratory are currently carried out by electrophoresis in acrylamide or agarose gels. This labor-intensive method is now being challenged by capillary electrophoresis (CE) because of its potential for automated, rapid, high efficiency separations. The automatability of CE itself, combined with its amenability to interfacing with other robotized functions, positions this technology perfectly for the analysis of proteins in physiological matrices, such as serum, urine, and cerebrospinal fluid. The focus of this overview is to familiarize the clinical scientist with the research demonstrating the applicability of the technology to the clinical protein laboratory. PMID- 9372263 TI - Analysis of small molecules for clinical diagnosis by capillary electrophoresis. AB - The application of capillary electrophoresis (CE) for the analysis of small molecules in clinical research is growing steadily. Initial studies have dealt with separations of standards or compounds in clean matrices. However, later studies dealt with analysis of those compounds in serum, urine or tissues. Great progress has been accomplished in three areas of clinical interest: organic acids, amino acids and drug analysis. The analysis of these compounds by capillary electrophoresis has several distinct advantages: high resolution, simplicity, versatility and especially low operating costs. In many cases, the sample can be injected directly without complex pretreatment. Most of the described methods have been validated for their precision, linearity and accuracy. In forensic toxicology, the CE has been used for drug identification and as a complementary analytical method. PMID- 9372264 TI - Clinical potential of microchip capillary electrophoresis systems. AB - Clinical interest in the use of capillary electrophoresis (CE) has recently been extended to the microchip environment. Clinical analyses demand careful handling of complex samples that are often limited in quantity and in concentration. The integrated sample handling and analysis capabilities of microchip substrates thus seem ideally suited to clinical applications. This review surveys the development of sample handling (injection, mixing, and reaction) and separation elements on chip. The integration of these elements to create a variety of clinical analyzers has been demonstrated. The application of microchip CE systems to human serum protein analysis, immunoassay, and DNA studies is reviewed, along with various other clinical applications. In addition, the clinical potential of the lab-on-a chip concept is discussed. PMID- 9372265 TI - Microsatellite-based cancer detection using capillary array electrophoresis and energy-transfer fluorescent primers. AB - The development of sensitive, rapid, and accurate methods and apparatus for high throughput short tandem repeat (STR) analysis will be critical for the use of microsatellite alteration in cancer screening. Here we show that STR-based bladder cancer diagnosis can be performed using capillary array electrophoresis and two-color labeling with energy-transfer (ET) fluorescent primers. Rapid (< or = 35 min) separations are achieved on capillary arrays using replaceable separation matrices and the allelic ratios are quantitatively determined with a precision of +/- 10%. With this precision, a variation of 20% was considered diagnostically significant. These methods provide a significant improvement in the speed, ease, and precision of STR analyses compared to slab gel electrophoresis. PMID- 9372266 TI - Use of capillary electrophoresis with laser-induced fluorescence detection to assess messenger ribonucleic acid molecules amplified by the polymerase chain reaction: applications in the cloning of cells. AB - Progressive and selective degeneration of specific classes of neurons occurs in the Alzheimer's disease (AD) brain. Differential vulnerability in this disease is evident even within supopulations that synthesize and release acetylcholine as a transmitter; i.e., basal forebrain cholinergic neurons degenerate but other classes of cholinergic neurons are relatively preserved. The basis for this selective vulnerability is unknown. Studies of differential neuronal vulnerability in AD would be facilitated if cell lines expressing neurotransmitter-specific phenotypes could be cloned from the brain. Capillary electrophoresis (CE) with laser-induced fluorescence (LIF) has been shown to be a sensitive method of detection and quantitation of the DNA products of the polymerase chain reaction (PCR). CE/LIF was combined with the PCR to detect phenotypic messenger RNA (mRNA) molecules, converted to cDNA using reverse transcriptase (RT), in cultures of virally immortalized brainstem progenitor cells produced during establishment of a cloning strategy. RT/PCR methods were developed for detection of the mRNAs for choline acetyltransferase (ChAT), the neuronal, constitutive isoform of nitric oxide synthase (c-NOS), and the growth associated protein GAP-43, three genes known to be expressed in central cholinergic neurons. A "nondestructive" method of screening cultured cells for their expression of c-NOS was established using depolarization with medium containing 50 mM potassium ion. These approaches were first validated using cultured SN56 (cholinergic) and N1E-115 (c-NOS-positive) neuroblastoma cells, and with primary brainstem cultures. For the cloning of novel cell lines, progenitor cells were isolated from the embryonic day 13 fetal brainstem and were immortalized by transfection with a retroviral vector that confers a temperature sensitive SV-40 transforming activity and neomycin resistance. Cell colonies surviving in G418-containing media were isolated and cloned by dilution. Clonal cultures were expanded by growth at 33 degrees C, differentiated by switching to a low-serum medium and growth at 39 degrees C, and screened for depolarization induced accumulation of nitrite in the medium. The subset of putative c-NOS positive clones (about 4%) were then screened for their expression of mRNAs using RT/PCR in combination with CE/LIF. This screening protocol proved to be powerful in the rapid isolation and phenotypic characterization of immortalized progenitor cells cloned from embryonic rat brainstem. PMID- 9372267 TI - Measurements of catecholamine-mediated apoptosis of immunocompetent cells by capillary electrophoresis. AB - Single cell analysis with capillary electrophoresis, a technique capable of detecting zeptomole quantities (10(-21) mole) of neurochemical species, has been used to demonstrate that lymphocytes are capable of active synthesis of dopamine and norepinephrine. Exposure of lymphocytes to catecholamines at concentrations as low as 10 nM leads to decreased proliferation and differentiation, e.g. interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and immunoglobulin (Ig). In addition, both inhibition of dopamine uptake with nomifensine and inhibition of packing of catecholamines into vesicles with tetrabenazine, results in significantly lower levels of dopamine and norepinephrine (p < 0.01 and p < 0.05, respectively). The catecholamine-dependent inhibition of T- and B-lymphocyte activity is mediated via an induction of a Bcl-2/Bax and Fas/FasL involved apoptosis. These findings indicate a novel mechanism for regulation of lymphocyte activity in the central nervous system, whereby elevated regional levels of catecholamines might lead to the immunoprivilege of the brain. PMID- 9372268 TI - Hydrophobic peptide mapping of clinically relevant heptathelical membrane proteins by capillary electrophoresis. AB - The structural investigation of G protein-coupled receptors has been hindered by the lack of techniques to effectively resolve the hydrophobic peptides obtained by chemical or proteolytic cleavage, as well as the minute amounts of protein typically isolated. We have developed a capillary electrophoresis method for efficient separation of hydrophobic peptides using a cyanogen bromide digest of bacteriorhodopsin as a model for these clinically important membrane proteins. This procedure includes (i) solubilization of the protein digest in acetic acid; and (ii) electrophoresis using an acetic acid-based buffer system augmented by acetonitrile and hexane sulfonic acid, in a Polybrene-coated fused silica capillary. The potential for detection sensitivity to be increased at least 100 fold by use of on-line solid-phase extraction on C18-silica is shown. This approach is potentially useful for peptide fingerprinting of sparse and extremely hydrophobic membrane receptors. PMID- 9372269 TI - Identification of monoclonal proteins in serum: a quantitative comparison of acetate, agarose gel, and capillary electrophoresis. AB - A selected group of 308 sera were analyzed by capillary electrophoresis (CE), agarose gel electrophoresis (AGE), and cellulose acetate electrophoresis (CAE) and evaluated for abnormalities that would suggest the presence of a monoclonal protein. The sensitivity (an electrophoretic abnormality in sera that contained a monoclonal protein) and specificity (a normal electrophoretic pattern in sera that did not contain a monoclonal protein) was determined for each electrophoretic procedure. CAE was the most specific procedure and CE was the most sensitive. The increase in sensitivity of CE was primarily due to increased detection of cryoglobulins and free light chains. The quantitation of the gamma region and/or monoclonal antibody peaks by CE was similar to results obtained by AGE. Quantitation of very large monoclonal protein peaks (> 3.0 g/dL) by on-line absorption detection (CE) yielded higher results than quantitation by dye-binding (AGE). PMID- 9372270 TI - Comparison of serum protein electrophoresis by agarose gel and capillary zone electrophoresis in a clinical setting. AB - Capillary zone electrophoresis (CZE) offers the potential for automating serum protein electrophoretic analysis traditionally performed on standard thin-layer agarose gels. The following describes the use of CZE compared to agarose gel electrophoresis (AGE) for the detection of dysproteinemia and paraproteinemia in a clinical study involving 240 patients. The study includes within-run and between-run reproducibility data on the Paragon CZE 2000 Clinical Capillary Electrophoresis System, in addition to concordance data between the two methodologies. Paraprotein quantitation studies comparing AGE versus CZE were also performed. Reproducibility for the automated CZE system was superior to the AGE system. Improved reproducibility for the CZE method is largely due to measuring protein absorbance directly at 214 nm versus the traditional AGE method that measures the amount of dye adsorbed to protein. Reproducibility data as percent coefficient of variance (% CV) for the five classic bands in a normal control serum for between-run precision ranged from 1.2 to 4.5% for CZE compared to AGE, which ranged from 3.8 to 8.0% CV. Concordance studies between AGE and CZE involving dysproteinemias including hypogammaglobulinemia, polyclonal and monoclonal gammopathies, acute and chronic inflammation, nephrosis, hepatodegenerative disease, cirrhosis, and iron deficiency anemia showed 96% agreement. Paraprotein classification, which compared the CZE immunosubtraction method to immunofixation electrophoresis (IFE) on agarose, showed 100% agreement. Certain dysproteinemias involving beta lipoprotein were in partial concordance due to the inability of the CZE procedure to detect this component. Detection limits for monoclonal gammopathies, providing they were not comigrating with other proteins, were IgG 50 mg/dL, IgM 75 mg/dL, and IgA 75 mg/dL. Paraprotein quantitative studies between the two methods showed less than a +/- 0.2 g/dL variation. PMID- 9372271 TI - Capillary isoelectric focusing of hemoglobin variants in the pediatric clinical laboratory. AB - We have used capillary isoelectric focusing (cIEF) to diagnose and monitor hemoglobinopathies in children for over three years. This report describes a major revision of our original method (Clin. Chem. 1994, 40, 2288-2295) that improves the analysis of hemoglobin (Hb) variants by cIEF, especially capillary performance and quantitation precision for minor variants. The revised method uses mixed ampholytes (2% pH 6-8:3-10; 10:1), lower viscosity methylcellulose (0.375%) solution, between-sample capillary conditioning with methanol, and hemolysates prepared from red blood cells (RBC) instead of whole blood. Collectively, these changes prolonged capillary life by minimizing capillary exposure to NaOH, standardized the sample matrix, and improved the precision of peak autointegration. The between-run quantitation imprecision (% relative standard deviation) of the revised method was 0.1-3.5% for all diagnostically important major and minor Hb variants present at normal or abnormal levels. The results show the use of the revised method for (i) posttranslationally modified Hb present at low concentrations in normal blood, (ii) Hb oxidation products produced by improper sample storage, (iii) differential diagnosis of S/beta + thalassemia, G-Philadelphia trait, S/C-Harlem disease, and Hb H disease, (iv) sensitive detection of minor variants like Hb A2' as indicators of an alpha globin mutation, and (v) neonatal screening using dried blood collected on filter paper. The results show that high-efficiency separation and precise quantitation of Hb variants over a wide range of concentrations makes cIEF a comprehensive assay that can be used without adjunct analyses for the automated primary evaluation of hemoglobinopathies and thalassemias. PMID- 9372273 TI - Analytical capillary isotachophoresis of human serum lipoproteins. AB - An analytical free flow capillary isotachophoresis (cITP) procedure for the detailed analysis of lipoproteins on commercially available capillary electrophoresis systems has been developed. The technique is based on the specific staining of lipoproteins with the fluorescent lipophilic dye 7-nitrobenz 2-oxa-1,3-diazole (NBD)-ceramide before separation. Prestained lipoprotein samples are applied between leading and terminating buffer and separated into 9 well-characterized subpopulations according to their electrophoretic mobility in the absence of any molecular sieve effect. High density lipoproteins are separated into three major subpopulations: (i) the fast migrating high density lipoprotein (HDL) subpopulation (alpha-HDL, containing mainly apolipoprotein (apo) A-I and phosphatidylcholine, (ii) the subpopulation with intermediate mobility, consisting of particles rich in cholesterol, apo A-II, apo E and C apolipoproteins, and (iii) the slow migrating HDL subpopulation (pre-beta-HDL), containing particles rich in apo A-I, apo A-IV. The majority of HDL-associated lecithin:cholesterol acyltransferase (LCAT) activity is also associated with the last subpopulation. The apo B-containing lipoproteins can be subdivided into three major functional groups. The first represents chylomicron derived particles and large triglyceride-rich very low density lipoproteins (VLDL). The second group consists of small VLDL and intermediate density lipoprotein (IDL) particles, and the third group represents the low density lipoproteins (LDL). Results obtained by the isotachophoretic lipoprotein analysis revealed a good correlation in the range of HDL with routinely used techniques, like lipoprotein electrophoresis, HDL-cholesterol analysis by a precipitation procedure or turbidimetric determination of apo A-I. Similar correlations with other analytical techniques were found for the quantitation of the apo B-containing lipoproteins. Advantages of the isotachophoretic separation compared to zone electrophoresis are the high resolution combined with small sample volumes. Moreover, lipoprotein analysis can be performed directly from whole serum, plasma, lymph and other biological fluids in a short time. With these characteristics analytical capillary isotachophoresis may be a helpful tool for a fast and reliable automated quantitation of lipoprotein subpopulations in the clinical laboratory. PMID- 9372272 TI - Development of a lipoprotein profile using capillary electrophoresis and mass spectrometry. AB - A new program for lipoprotein characterization is outlined where capillary electrophoresis (CE) plays a central role in the analysis of intact lipoprotein serum components and the apoprotein domains. The first characterization step involves separation and particle density analysis of very low-, low-, and high density lipoprotein fractions (VLDL, LDL, HDL) by ultracentrifugation and image analysis. VLDL, HDL, and LDL fractions are analyzed by capillary electrophoresis. Sodium dodecyl sulfate (SDS) at low concentrations in the background electrolyte used in the CE analysis is incorporated into the lipoprotein particle without appreciable delipidation, as determined by ultracentrifuge particle density analysis. Increasing the concentration of SDS results in extensive delipidation, resulting in the release of apoproteins (apo) which are detected as components of the electropherogram. Apo B-100 is detected in the delipidated VLDL and LDL fractions along with micelles of the lipids. Micelles from LDL delipidation have uniform charge densities. Apo A-I and A-II are detected in the HDL fraction. A new method for lipoprotein delipidation is introduced where the lipoprotein fraction is adsorbed on a reversed-phase hydrophobic cartridge. Delipidation and recovery of the apoprotein fractions is made by serial elutions with acetonitrile. CE of the lipid-free apoprotein mixture shows the presence of apoC I,II,III and apoE in the VLDL fraction, and apoA-I,II apoC-I and apoE in the HDL fraction. Electrospray ionization mass spectrometry analysis gives the isoform distribution for each apoprotein. The identification of the apoproteins in the electropherograms is the first step in developing a CE-based quantitation method for measuring serum levels of these apoproteins and their distribution between the lipoprotein fractions. The assay described in this paper is being used as a level 2 and 3 cardiac risk profile analysis for individuals with normal lipid profiles who have a documented or family history of cardiovascular disease. PMID- 9372274 TI - Analysis of carbohydrate deficient transferrin by capillary zone electrophoresis. AB - We report a capillary zone electrophoresis method to separate the various sialylated isoforms of transferrin. The separation is carried out under nondenaturing conditions and at basic pH. Under these conditions, transferrin exhibits two major and three minor peaks. Plasma samples from a population consuming varying amounts of alcohol at different intervals were studied. A cut off value of 3% carbohydrate deficient transferrin (CDT: disialo, monosialo, and asialo transferrin), results in a clinical sensitivity of 88% in a population consuming at least 70 g/day alcohol for a minimum of two weeks. The sensitivity dropped significantly in a population consuming less than 70 g/day. This confirms previous reports of CDT as a specific marker for significant and chronic use of alcohol. Capillary electrophoresis offers an alternative method with respect to analysis time and throughput in the clinical laboratory. PMID- 9372275 TI - Capillary electrophoresis-based separation of transferrin sialoforms in patients with carbohydrate-deficient glycoprotein syndrome. AB - The heterogeneity associated with protein glycoforms has been a challenge to analytical chemists and the subject of structure-function studies for biochemists since their presence in biological systems had been confirmed some three decades ago. Initial investigations led to discoveries of synthetic and degradative pathways, and brief forays into functional determination of the "glyco" portion on the protein activity in glycoproteins. Only recently has it come to our understanding that variations from the "normal" glycosylation patterns might be indicative of pathological states. The presence of certain transferrin (Tf) glycoforms in human serum has been shown to correlate with certain clinical syndromes. Hence, the ability to separate and quantitatively measure the various forms of human Tf has become increasingly important. It this study, we demonstrate that a simple method utilizing a DB-17-coated capillary to slow endoosmotic flow and a sieving buffer containing hydroxyethyl cellulose allows for the resolution of sialoforms of transferrin. An analysis time of less than eight minutes allows for baseline resolution of the lower sialoforms of Tf, presenting a simple, rapid test for carbohydrate-deficient transferrin (CDT). We demonstrate the utility of this methodology for the facile diagnosis of carbohydrate-deficient glycoprotein syndrome, and postulate that it may allow for the detection of other carbohydrate-deficient protein-related disease states. PMID- 9372276 TI - Development of a nonisotopic capillary electrophoresis-based method for measuring glomerular filtration rate. AB - The conditions for quantitative measurement of nonisotopic iothalamate meglumine (Conray) in urine and plasma by capillary zone electrophoresis (CE) have been developed. The impetus for developing this methodology was to replace the traditional [125I]iothalamate glomerular filtration rate (GFR) marker assay, a routine tool in the measurement of kidney function. This new approach for measuring kidney function is attractive since it avoids the cost of administration of radioisotopic compounds to patients, as well as the cost associated with purchase and disposal of isotopic compounds and contaminated samples. The concentration of iothalamate in urine and plasma determined by CE can be used directly to calculate GFR. The GFR in patients injected with [125I]iothalamate and nonisotopic iothalamate simultaneously showed an excellent correlation (0.998) with between-day coefficient of variation of 2.30% and a recovery of 102% and 98%, respectively, when added to urine and plasma. Interference from drugs and other urinary compounds is eliminated with this method. Collectively, this study has shown that CE is a cost-effective alternative to the current methodology for measuring GFR. PMID- 9372277 TI - Urine protein analysis by capillary electrophoresis. AB - Increased concentration of proteins in urine as well as abnormal patterns are seen in many disorders such as various renal disorders and light chain disease. At the wavelength of 214 nm used for detection of the peptide bond, numerous compounds interfere in the analysis of urinary proteins. We show that either adsorptive filtration with a wash step or cold ethanol precipitation are two methods which can eliminate many of the interferences. The wash step is rapid, greatly reduces the interfering substances, and decreases the effect of sample matrix. Both of these methods yield results comparable to the traditional agarose method. Capillary electrophoresis (CE) is faster and more cost-effective than agarose electrophoresis. PMID- 9372278 TI - Clinical application of capillary electrophoresis to unconcentrated human urine proteins. AB - Urine protein electrophoresis can be performed by capillary electrophoresis using spun unconcentrated urine diluted with running buffer. The separation which utilises the excellent sensitivity of capillary electrophoresis gives electropherograms similar to those obtained by diluting concentrated urine with buffer. A 72 cm x 50 microns internal diameter (ID) fused silica capillary was used for the analysis which took less than 15 min. Bence Jones protein can be detected from unconcentrated urine over urine protein concentrations ranging from 9.7 g/L to 0.04 g/L. Other clinical patterns, such as glomerular proteinuria, the presence of intact immunoglobulin and Tamm Horsfall protein can also be detected. The benefit of using unconcentrated urine is the time and cost saved by not concentrating the urine. PMID- 9372279 TI - Micellar electrokinetic capillary chromatography (MECC) of UV-absorbing constituents in normal urine: a chemometric optimisation of the separation. AB - A micellar electrokinetic capillary chromatography (MECC) method when compared to free solution capillary electrophoresis (CZE) was shown to offer improved selectivity and resolution for the separation of UV-absorbing components of human urine. Some of the factors affecting MECC separation e.g. methanol concentration, sodium dodecyl sulphate (SDS) concentration, beta-cyclodextrin (beta-CD) concentration, voltage, pH, temperature and electrolyte additives (urea, beta-CD and Brij 35) were optimised using chemometric techniques. Three-level three factor (3(3)) factorial designs and simplex optimisation were used to achieve optimised conditions with the goal of obtaining the maximum number of peaks in the shortest possible analysis time. Using a TSP CE2000 instrument with detection from 195-300 nm and fitted with a 75 microns x 44 cm (37 cm effective length) fused silica capillary the final optimum conditions were found to be, an electrolyte consisting of 30 mM sodium tetraborate, pH 10, containing 75 mM SDS and 10 mM beta-CD, 15 degrees C, 20 kV, 4 s hydrodynamic injection of filtered urine. These conditions were capable of separating 70 peaks from a normal human urine pool in less than 12 min. The separation of components in urine using the optimised MECC was simpler, more reproducible, faster and gave better resolution than gradient reversed-phase high performance liquid chromatography. PMID- 9372280 TI - Capillary electrophoresis for diagnosis of metabolic disease. AB - Capillary electrophoresis (CE) equipped with a diode-array detector have been used to determine diagnostic metabolites occurring in urine of patients with various diseases. The urine samples were injected directly onto the CE instrument without any pretreatment. Identification of abnormal metabolites was based on relative migration times and characteristic diode-array spectra. The CE-method readily diagnosed alkaptonuria, neuroblastoma and liver failure due to galactosemia. The simple and automated CE method appears to be suitable for implementation as a screening test in analytical systems aimed at diagnosis of metabolic disorders. PMID- 9372281 TI - Determination of serum corticosteroids by mixed micellar electrokinetic capillary chromatography with sodium dodecyl sulfate and sodium cholate. AB - The application of mixed micellar electrokinetic capillary electrochromatography to the determination of the corticosteroid hormones cortisone, cortisol (hydrocortisone), and dexamethasone in serum samples is demonstrated. The serum samples were enzymatically hydrolyzed, precipitated, solid-phase extracted, and analyzed by capillary electrophoresis. A micellar system of sodium dodecyl sulfate and sodium cholate buffered with an organic compound provided the electrolyte solution. Spiked blank serum samples were used for the linearity testing and limits of detection and quantitation were measured. Patient samples were analyzed and the concentrations of cortisol and cortisone were measured. The method, which was fast and easy to perform, was confirmed to be useful for the determination of corticosteroids in serum. PMID- 9372282 TI - Capillary electrophoretic detection of metabolites in the urine of patients receiving hypoglycemic drug therapy. AB - Micellar electrokinetic chromatography (MEKC) in tandem with diode array detection (DAD) has been exploited as an analytical method for the separation and detection of sulfonylurea drugs. The ultimate goal is the development of an assay to detect these drugs or their metabolites in urine as a means of diagnosing sulfonylurea drug abuse. Using a separation buffer consisting of 5 mM borate/5 mM phosphate/75 mM sodium cholate, separation of both the second and third generation sulfonylurea drugs can be achieved. The characteristic absorbance spectra associated with each of the third generation drugs, glipizide and glyburide, allow for their identification in mixtures. Coinjection of glyburide, its primary metabolite, hydroxy glyburide, and glipizide demonstrated that the metabolite was resolved from the parent drug but shared its absorbance spectral properties. MEKC analysis of a series of solid phase-extracted urine samples from patients prescribed glipizide or glyburide, as well as from control patients not ingesting the drug, showed that the parent compounds were difficult to detect in the urine. However, the use of DAD allowed for detection of metabolites in the urine of these patients. With glyburide patients, only primary metabolites were detected, while urine from patients on glipizide showed a series of peaks whose absorbance spectra was consistent with the presence of both primary and secondary metabolites. In addition, the intensity of the metabolite peaks corresponded reasonably well with the respective dose and in vivo time interval associated with the urine collection. This study shows that MEKC with DAD has potential for further exploration as a clinical assay for detecting surreptitious abuse of sulfonylurea drugs. PMID- 9372283 TI - Characterization of stereoselectivity and genetic polymorphism of the debrisoquine hydroxylation in man via analysis of urinary debrisoquine and 4 hydroxydebrisoquine by capillary electrophoresis. AB - Using capillary zone electrophoresis with a phosphate buffer at pH 2.5 containing 50 mM heptakis-(2,3,6-tri-O-methyl)-beta-CD as chiral selector, the separation of the enantiomers of the main metabolite of debrisoquine (DEB), 4 hydroxydebrisoquine (4-OHDEB), is reported. For extraction of underivatized urinary DEB, S-4-OHDEB and R-4-OHDEB, a procedure using disposable cartridges containing a polystyrene-based polymer was developed. A few nL of the extracts were analyzed in a 60 cm fused-silica capillary of 50 microns ID and solute detection was effected at 195 nm. For all three compounds, a mean (n = 5) recovery of about 73% and a detection limit of about 150 ng/mL were noted. Data obtained with urines that were received for routine phenotyping with DEB and mephenytoin confirmed the almost exclusive formation of S-4-OHDEB. Under the described conditions, no R-4-OHDEB could be detected. With these data and those obtained employing no chiral selector in the buffer, differentiation between extensive metabolizer phenotypes (EM) and poor metabolizer phenotypes (PM) for DEB was unambiguously possible by the presence of a significant peak and no (or minor) peak for 4-OHDEB, respectively. Data obtained for ten EM subjects and five PM subjects were found to agree with those generated by the routine assay based on gas chromatography. The capillary electrophoretic assays described are simple, reproducible (relative standard deviation of peak area ratios < 3%), require no sample derivatization, consume no halogenated organic solvents, and operate with inexpensive separation columns as well as small amounts of chemicals. PMID- 9372284 TI - Determination of pharmaceuticals in plasma by capillary electrophoresis without sample pretreatment reproducibility, limit of quantitation and limit of detection. AB - Pharmaceuticals in human plasma are determined on underivatized fused-silica capillaries by micellar electrokinetic capillary chromatography (MEKC) without sample pretreatment. Our best method to date uses as running buffer a sodium dodecyl sulfate (SDS) containing borate buffer (60 mM with 200 mM SDS) at pH 10. Between runs, proteins adsorbed to the capillary wall are removed by an acetonitrile and SDS-buffer rinsing regimen (50% v/v each). A day-to-day precision for relative peak areas of about 2% relative standard deviation (RSD; n > 40) has been reached. Different rinsing approaches are discussed (salts, enzyme containing solutions, organic solvents, hydrofluoric acid). The separation system is tested in a concentration range between approximately 100 mg/L-10 mg/L. Correlations between the limit of quantitation, the limit of detection and the signal/noise are discussed. The applicability of the system is demonstrated for the pharmaceuticals acetaminophen, salicylic acid, sulfamethoxazole, tolbutamide, and trimethoprim. PMID- 9372285 TI - Determination of nitrite and nitrate reduction by capillary ion electrophoresis. AB - Production of nitrates and nitrites is a common step in many methodologies used to measure nitric oxide (NO) and NO-derived products in biological fluids. We report conditions that allow the rapid separation and quantification of nitrite from nitrate ions in biological fluids by capillary ion electrophoresis (CIE). CIE can be used to directly quantify nitrites and nitrates near the millimolar range. To detect lower levels, we have used CIE to monitor the reduction of nitrites and nitrates to NO for chemiluminescence detection. For reduction reactions, we directly compared the ability of three commonly used agents- potassium iodide (KI), mercuric chloride (HgCl2) and vanadium chloride (VCl3)--to reduce nitrite and nitrate ions to NO. Nitrites/nitrates can be efficiently reduced to NO at 37 degrees C using vanadium chloride (100%) or HgCl2 (80%). However, these CE-derived conditions cannot simply be extrapolated to chemiluminescence measurements. Vanadium (III) yields high background in the photomultiplier that diminishes the sensitivity of chemiluminescence measurement to that outside of physiological ranges. We find that reactions carried out at 37 degrees C in 2 M HCl using HgCl2 is efficient using both techniques. PMID- 9372286 TI - Analysis of endotoxins by capillary electrophoresis. AB - Endotoxins are part of the outer membrane of gram-negative bacteria such as E. coli. Upon entering the blood stream, they cause a violent, sometimes life threatening, response of the immune system. Endotoxins are lipopolysaccharides (LPS), lacking optically active groups, and their detection in the underivatized state can be difficult. In this paper the potential of capillary electrophoresis (CE) for LPS analysis is investigated. By using a standard phosphate buffer method, concentrations down to 100 micrograms/mL can be detected within 6 min. The detection limit can be lowered by one order of magnitude by using a sodium dodecyl sulfate (SDS)/borate buffer, pH 9.2. In this buffer, the SDS serves to homogenize the size of the LPS aggregates, while the borate forms complexes with the diol groups of the molecule, thereby enhancing its optical activity. The formation of LPS-affinity complexes with the UV-active polymyxin B or labeling of the LPS with a fluorophore (fluorescein isothiocyanate) was unsuccessful. Best results, in terms of detection limit and speed, were obtained with an indirect UV detection CE method. By using a strongly UV-active electrophoresis buffer, endotoxins could be detected as "negative" peaks. In this case, a detection limit of 3 micrograms/mL (35 pM) was determined. Proteins and other UV-active substances did not disturb the assay, since they generated no detectable signals. The indirect UV detection was used to quantify the residual LPS content of a DNA preparation from E. coli. PMID- 9372287 TI - Properties of saccular nerve-activated vestibulospinal neurons in cats. AB - Axonal pathways, projection levels, conduction velocities, and locations of the cell bodies of saccular nerve-activated vestibulospinal neurons were studied in decerebrated cats and anesthetized cats, using a collision test of orthodromic and antidromic spikes. The saccular nerve was selectively stimulated by bipolar tungsten electrodes. Three monopolar electrodes were inserted into the left and right lateral vestibulospinal tract (LVST) and medial vestibulospinal tract (MVST) of the C1 segment, to determine the pathway of axons. Three pairs of similar electrodes were positioned bilaterally in the C3-4, T1, and L3 segments to examine projection levels. Another monopolar electrode was placed in the oculomotor nucleus to determine whether saccular nerve-activated vestibulospinal neurons have branches ascending to the oculomotor nucleus. Of 145 vestibular neurons orthodromically activated by stimulation of the saccular nerve, 46 were activated from the C1 segment antidromically. Forty-three were second-order vestibulospinal neurons and 3 were third-order vestibulospinal neurons. Four saccular nerve-activated vestibulospinal neurons were also antidromically activated from the oculomotor nucleus. Sixty-three percent of the saccular nerve activated vestibulospinal neurons descended through the MVST; one-third of these terminated in the upper cervical segments, one-third reached the lower cervical segments and the remaining one-third reached the upper thoracic segments. Thirty percent of the saccular nerve-activated vestibulospinal neurons descended through the ipsilateral LVST; most of these reached the upper thoracic segments. Seven percent of the saccular nerve-activated vestibulospinal neurons descended through the contralateral vestibulospinal tracts terminating in the upper cervical segments. Most of the saccular nerve-activated vestibulospinal neurons originated in the caudal part of the lateral nucleus and rostral part of the descending nucleus. PMID- 9372288 TI - Influence of the superior colliculus on the primate blink reflex. AB - In this study we used microstimulation to investigate the influence of the superior colliculus on the trigeminal blink reflex. We report that stimulation in the intermediate to deep layers of the tectum produced inhibition of reflex blinks at a latency of approximately 26 ms. We considered the hypothesis that the blink inhibition was mediated via the omnipause neurons (OPNs) of the eye movement control system in the brainstem. Our results show that the least effective sites for suppression were in the rostral colliculus. This is inconsistent with the prediction that OPNs should be maximally recruited from the rostral tectum near the "fixation zone." From these points and other considerations, we conclude that the reflex blink suppression from the superior colliculus is not directly mediated by the OPNs or the saccadic eye movement circuits. PMID- 9372289 TI - Mitochondrial content of choroid plexus epithelium. AB - The objective of the present study was to examine the apparent work capacity of one of the two separate membrane systems (the blood-cerebrospinal fluid barrier) that isolate the mammalian brain extracellular fluid (and cerebrospinal fluid, CSF) from plasma. Digitized analyses of electron-microscopic images provided estimates of mitochondrial volumes, which were expressed as a percentage of the cell cytoplasm. We recorded a high mitochondrial content of 12-15% in the cuboidal epithelium of primate choroid plexus, which was consistent in vervet, rhesus, and squirrel monkeys, as well as in baboons. Similarly high mitochondrial contents were observed in the rabbit, rat, and mouse choroid plexus. It has been postulated that the high mitochondrial content of brain endothelium is associated with maintaining the ionic gradients within the central nervous system. We observed that the mitochondrial content of the choroid plexus (where CSF is produced) was slightly higher than in (prior measurements of) the blood-brain barrier (BBB). In addition, surface areas at the apical borders of the choroid plexus epithelia (where the Na+K+ATPase activity has been localized) were increased 7- to 13-fold over the basal borders, in the primate species examined. The observation of high mitochondrial volumes in choroid plexus cells is consistent with the suggestion that increased mitochondrial densities seen in choroidal epithelia and BBB capillaries provide a metabolic work capability for both secretory activities and maintaining ionic gradients across blood-CSF barriers. PMID- 9372290 TI - Manual interception of moving targets. I. Performance and movement initiation. AB - We investigated the capacities of human subjects to intercept moving targets in a two-dimensional (2D) space. Subjects were instructed to intercept moving targets on a computer screen using a cursor controlled by an articulated 2D manipulandum. A target was presented in 1 of 18 combinations of three acceleration types (constant acceleration, constant deceleration, and constant velocity) and six target motion times, from 0.5 to 2.0 s. First, subjects held the cursor in a start zone located at the bottom of the screen along the vertical meridian. After a pseudorandom hold period, the target appeared in the lower left or right corner of the screen and traveled at 45 degrees toward an interception zone located on the vertical meridian 12.5 cm above the start zone. For a trial to be considered successful, the subject's cursor had to enter the interception zone within 100 ms of the target's arrival at the center of the interception zone and stay inside a slightly larger hold zone. Trials in which the cursor arrived more than 100 ms before the target were classified as "early errors," whereas trials in which the cursor arrived more than 100 ms after the target were classified as "late errors." Given the criteria above, the task proved to be difficult for the subjects. Only 41.3% (1080 out of 2614) of the movements were successful, whereas the remaining 58.7% were temporal (i.e., early or late) errors. A large majority of the early errors occurred in trials with decelerating targets, and their percentage tended to increase with longer target motion times. In contrast, late errors occurred in relation to all three target acceleration types, and their percentage tended to decrease with longer target motion times. Three models of movement initiation were investigated. First, the threshold-distance model, originally proposed for optokinetic eye movements to constant-velocity visual stimuli, maintains that response time is composed of two parts, a constant processing time and the time required for the stimulus to travel a threshold distance. This model only partially fit our data. Second, the threshold-tau model, originally proposed as a strategy for movement initiation, assumes that the subject uses the first-order estimate of time-to-contact (tau) to determine when to initiate the interception movement. Similar to the threshold distance model, the threshold-tau model only partially fit the data. Finally, a dual strategy model was developed which allowed for the adoption of either of the two strategies for movement initiation; namely, a strategy based on the threshold distance model ("reactive" strategy) and another based on the threshold-tau model ("predictive" strategy). This model provided a good fit to the data. In fact, individual subjects preferred to use one or the other strategy. This preference was allowed to be manifested at long target motion times, whereas shorter target motion times (i.e., 0.5 s and 0.8 s) forced the subjects to use only the reactive strategy. PMID- 9372291 TI - Manual interception of moving targets. II. On-line control of overlapping submovements. AB - We studied the kinematic characteristics of arm movements and their relation to a stimulus moving with a wide range of velocity and acceleration. The target traveled at constant acceleration, constant deceleration, or constant velocity for 0.5-2.0 s, until it arrived at a location where it was required to be intercepted. For fast moving targets, subjects produced single movements with symmetrical, bell-shaped velocity profiles. In contrast, for slowly moving targets, hand velocity profiles displayed multiple peaks, which suggests a control mechanism that produces a series of discrete submovements according to characteristics of target motion. To analyze how temporal and spatial aspects of these submovements are influenced by target motion, we decomposed the vertical hand velocity profiles into bell-shaped velocity pulses according to the minimum jerk model. The number of submovements was roughly proportional to the movement time, resulting in a relatively constant submovement frequency (approximately 2.5 Hz). On the other hand, the submovement onset asynchrony showed significantly more variability than the intersubmovement interval, indicating that the submovement onset was delayed more following a submovement with a longer duration. Examination of submovement amplitude and its relation to target motion revealed that the subjects achieved interception mainly by producing a series of submovements that would keep the displacement of the hand proportional to the first-order estimate of target position at the end of each submovement along the axis of hand movement. Finally, we did not find any evidence that information regarding target acceleration is properly utilized in the production of submovements. PMID- 9372292 TI - Motion processing in pigeon tectum: equiluminant chromatic mechanisms. AB - Recent psychophysical and neurophysiological studies have suggested that, in mammals, there are interactions between the P (colour processing) and M (motion processing) visual pathways, which were previously believed to be parallel and separate. In this study, the role colour information plays in the coding of object motion was determined in the tectofugal pathway of pigeons. The responses of motion-sensitive neurons in the tectum to moving stimuli formed by chromatic contrast were recorded extracellularly using standard single-unit recording techniques. A moving coloured object was presented on a uniform (opponent coloured) background (e.g. blue-on-yellow, red-on-green and black-on-white). Through systematically manipulation of the luminance contrast between object and background, an equiluminant condition was generated. It was found that, at chromatic equiluminance, the majority of cells maintain some level of response. The mean magnitude of the response at equiluminance was about one-third of the response at maximal contrast to the same chromatic border. These results suggest that tectal units can detect motion of a pattern defined by a pure colour contour, although the strength of output is considerably weaker than that for the movement of patterns formed by luminance contrast. PMID- 9372293 TI - Volitional control of anticipatory ocular smooth pursuit after viewing, but not pursuing, a moving target: evidence for a re-afferent velocity store. AB - Although human subjects cannot normally initiate smooth eye movements in the absence of a moving target, previous experiments have established that such movements can be evoked if the subject is required to pursue a regularly repeated, transient target motion stimulus. We sought to determine whether active pursuit was necessary to evoke such an anticipatory response or whether it could be induced after merely viewing the target motion. Subjects were presented with a succession of ramp target motion stimuli of identical velocity and alternating direction in the horizontal axis. In initial experiments, the target was exposed for only 120 ms as it passed through centre, with a constant interval between presentations. Ramp velocity was varied from +/- 9 to 45 degrees/s in one set of trials; the interval between ramp presentations was varied from 640 to 1920 ms in another. Subjects were instructed either to pursue the moving target from the first presentation or to hold fixation on another, stationary target during the first one, two or three presentations of the moving display. Without fixation, the first smooth movement was initiated with a mean latency of 95 ms after target onset, but with repeated presentations anticipatory smooth movements started to build up before target onset. In contrast, when the subjects fixated the stationary target for three presentations of the moving target, the first movement they made was already anticipatory and had a peak velocity that was significantly greater than that of the first response without prior fixation. The conditions of experiment 1 were repeated in experiment 3 with a longer duration of target exposure (480 ms), to allow higher eye velocities to build up. Again, after three prior fixations, the anticipatory velocity measured at 100 ms after target onset (when visual feedback would be expected to start) was not significantly different to that evoked after the subjects had made three active pursuit responses to the same target motion, reaching a mean of 20 degrees/s for a 50 degrees/s target movement. In a further experiment, we determined whether subjects could use stored information from prior active pursuit to generate anticipatory pursuit in darkness if there was a high expectancy that the target would reappear with identical velocity. Subjects made one predictive response immediately after target disappearance, but very little response thereafter until the time at which they expected the target to reappear, when they were again able to re-vitalize the anticipatory response before target appearance. The findings of these experiments provide evidence that information related to target velocity can be stored and used to generate future anticipatory responses even in the absence of eye movement. This suggests that information for storage is probably derived from a common pre-motor drive signal that is inhibited during fixation, rather than an efference copy of eye movement itself. Furthermore, a high level of expectancy of target appearance can facilitate the release of this stored information in darkness. PMID- 9372294 TI - Responses of tonically discharging neurons in the monkey striatum to primary rewards delivered during different behavioral states. AB - In the primate striatum, the tonically discharging neurons respond to conditioned stimuli associated with reward. We investigated whether these neurons respond to the reward itself and how changes in the behavioral context in which the reward is delivered might influence their responsiveness. A total of 286 neurons in the caudate nucleus and putamen were studied in two awake macaque monkeys while liquid reward was delivered in three behavioral situations: (1) an instrumental task, in which reward was delivered upon execution of a visually triggered arm movement; (2) a classically conditioned task, in which reward was delivered 1 s after a visual signal; (3) a free reward situation, in which reward was delivered at irregular time intervals outside of any conditioning task. The monkeys' uncertainty about the time at which reward will be delivered was assessed by monitoring their mouth movements. A larger proportion of neurons responsive to reward was observed in the free reward situation (86%) than in the classically conditioned (57%) and instrumental tasks (37%). Among the neurons tested in all situations (n = 78), 24% responded to reward regardless of the situation and 65% in only one or two situations. Responses selective for one particular situation occurred exclusively in the free reward situation. When the reward was delivered immediately after the visual signal in the classically conditioned task, most of the neurons reduced or completely lost their responses to reward, and other neurons remained responsive. Conversely, neuronal responses invariably persisted when reward was delivered later than 1 s after the visual signal. This is the first report that tonic striatal neurons might display responses directly to primary rewards. The neuronal responses were strongly influenced by the behavioral context in which the animals received the reward. An important factor appears to be the timing of reward. These neurons might therefore contribute to a general aspect of behavioral reactivity of the subject to relevant stimuli. PMID- 9372296 TI - Electrophysiological evidence that spinomesencephalic neurons in the cat may be excited via spinocervical tract collaterals. AB - Extracellular microelectrode recordings were made from spinomesencephalic tract (SMT) neurons in the lumbosacral spinal cord of cats anaesthetized with chloralose and paralysed with gallamine triethiodide. The SMT cells were antidromically fired from the posterolateral parts of the superior colliculus and the intercollicular region, were located in laminae IV to VIII, and had response properties and axonal conduction velocities similar to those described previously. The effects of stimulating the dorsolateral funiculus of the cervical cord at C3 and rostral C1, below and above the termination of spinocervical tract (SCT) axons in the lateral cervical nucleus, were examined on 33 SMT cells. The strength of stimulation was adjusted so that at C3 it was above threshold for antidromic activation of SCT cells and at C1 was below threshold for activation of the same cells. Seven (21%) SMT neurons were excited from C3 but not from C1. The remaining 26 (79%) were excited from both C3 and rostral C1 and 23 (70% of these) were excited significantly more from C3. That is, 91% of the total sample were either excited only from C3 or more strongly from C3 than from rostral C1. We discuss the possible neuronal systems involved and conclude that the greater excitatory effects from C3 are most likely due to antidromic activation of the SCT. The shortest latency effects from C3 indicate a monosynaptic linkage between SCT cells with the fastest axons and the SMT. The longer latency actions may be due to monosynaptic connexions from SCT cells with slower conducting axons, to di or polysynaptic actions from SCT cells with fast axons, or a combination of both. SMT cells are another population of spinal neurons, in addition to postsynaptic dorsal column, spinothalamic and dorsal horn spinocerebellar neurons, which receive excitation via SCT collaterals. PMID- 9372295 TI - Neuronal damage and MAP2 changes induced by the glutamate transport inhibitor dihydrokainate and by kainate in rat hippocampus in vivo. AB - Neurotoxicity mediated by glutamate is thought to play a role in neurodegenerative disorders, and alterations in cytoskeletal proteins are possibly involved in the mechanisms of neuronal death occurring in Alzheimer's disease. In the present work we studied the neurotoxic effects of the intrahippocampal injections of the glutamate transport inhibitor dihydrokainate as compared to those of kainate, as well as the concomitant changes in the microtubule-associated protein MAP2. Neuronal alterations were assessed at 3, 12, 24, and 48 h by Nissl staining and immunocytochemistry of MAP2. At 3 h, both compounds induced neuronal damage that was correlated with loss of dendritic MAP2 immunoreactivity. Neuronal damage was more evident at 12 h and 24 h after drug injection, and at these times an accumulation of MAP2 in the somata of pyramidal neurons was observed. The effects of dihydrokainate were restricted to the CA1 region and totally prevented by the N-methyl-D-aspartate receptor antagonist (+) 5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801), but not by the non-NMDA receptor antagonist 2,3-dihydro-6-nitro-7-sulphamoyl benzo(f)-quinoxaline (NBQX). In contrast, kainate-induced alterations included CA1, CA3, and CA4 subfields, and the changes in CA1 were prevented by NBQX, while MK-801 was ineffective. These results suggest that early MAP2 disruption may be a marker of the excitotoxicity due to activation of different glutamate receptors located in discrete hippocampal regions. PMID- 9372297 TI - Visual perceptions of vertical and intrinsic longitudinal axes. AB - The purpose of these experiments was to investigate whether visual perceptions of the earth-fixed vertical axis are more accurate than those of intrinsic body fixed axes. In one experiment, nine neurologically normal young adult subjects' abilities to position a luminescent rod vertically or parallel to the longitudinal axis of the head or trunk were studied in four conditions: (1) earth fixed--subjects stood erect with the head aligned to the trunk and visually aligned a hand-held rod to vertical; (2) earth--subjects aligned the rod to vertical as in 1, but the orientations of the head and trunk were varied in the sagittal and frontal planes on each trial; (3) head--frontal and/or sagittal plane orientation of the subject's head was varied on each trial and the rod was aligned parallel to the longitudinal axis of the head; (4) trunk--frontal and/or sagittal plane orientation of the subject's trunk was varied on each trial and the rod was aligned parallel to the longitudinal axis of the trunk. Note that in conditions 2, 3, and 4 the head and trunk were never aligned with each other. Also, each condition was carried out in normal light and in complete darkness. Perceptual errors were measured in both the frontal and the sagittal planes. The results showed that the variable errors were significantly lower when subjects aligned the rod to vertical rather than to the longitudinal axis of the head or trunk. Also, errors were similar in size in the two planes and were unaffected by vision of the surrounding environment. In a second experiment, subjects were seated and controlled the position of a luminescent rod held by a robot. They aligned the rod either to the longitudinal axis of their head or to the vertical in complete darkness, under three conditions similar to those described above: (1) earth-fixed, (2) earth, and (3) head. There was no possibility of use of kinesthetic information for controlling rod position in this experiment as in the first experiment. The results were similar to those of the first experiment, as subjects aligned the rod more accurately to vertical than to the longitudinal axis of the head. These results show convincingly that visual perceptions of earth-fixed vertical are more accurate than perceptions of intrinsic axes fixed to the head or trunk. PMID- 9372298 TI - Neglect as a deficit determined by an imbalance between multiple spatial representations. AB - A previous study on neglect suggested that at least two hand parameters are crucial in producing an amelioration of neglect: the hand (left or right) and the spatial position of the hand (left or right). The improvement observed in perceiving left targets when the left hand acts in the left space can be due either to proprioceptive or to visual cuing. The stimulated left hand located in the left space may act as a powerful visual cue for the enhancement of the left visuo-spatial representation, in the same way as any other visual stimulus presented in the periphery of the visual field. Alternatively, it may be that the perceived hand location (due to the activation of the proprioceptive system) acts as an attentional field able to enhance the representation of the left space. In order to disentangle these two hypotheses, in the present study a naming task was executed by a group of neglect patients and by a control group. The subjects had to name all the objects depicted on a sheet of paper which were reflected on a mirror that inverted right and left space. While doing the naming performance, the subjects passively moved either the right or the left hand, in the left or right space. Stimuli and hand were reflected in the mirror that inverted right and left space and direct view of the stimuli and of the stimulated hand was prevented by a board. The results show that patients were more accurate at naming stimuli reflected in the left side of the mirror when the left hand was located and moved on the left side. In this condition, however, the left hand was seen in the right side of the mirror. It is therefore clear that the better performance was not due to visuo-spatial cuing but to a proprioceptive cuing effect. The results are discussed in terms of the relevance of personal and peripersonal spatial activation in the modulation of extrapersonal visual neglect. The coactivation of different spatial representations seems to be very influential on stimulus coding, thus confirming that spatial awareness is strictly related to the joint activity of multiple brain maps. PMID- 9372300 TI - The directional effects of passive eye movement on the directional visual responses of single units in the pigeon optic tectum. AB - We have investigated the visual responses of 184 single units located in the superficial layers of the optic tectum (OT) of the decerebrate, paralysed pigeon. Visual responses were similar to those reported in non-decerebrate preparations; most units responded best to moving visual stimuli, 18% were directionally selective (they had a clear preference for a particular direction of visual stimulus movement), 76% were plane-selective (they responded to movement in either direction in a particular plane). However, we also found that a high proportion of units showed some sensitivity to the orientation of visual stimuli. We examined the effects of extraocular muscle (EOM) afferent signals, induced by passive eye movement (PEM), on the directional visual responses of units. Visual responses were most modified by particular directions of eye movement, although there was no unique relationship between the direction of visual stimulus movement to which an individual unit responded best and the direction of eye movement that caused the greatest modification of that visual response. The results show that EOM afferent signals, carrying information concerning the direction of eye movement, reach the superficial layers of the OT in the pigeon and there modify the visual responses of units in a manner that suggests some role for these signals in the processing of visual information. PMID- 9372301 TI - Interferon modulates glucose-sensitive neurons in the hypothalamus. AB - Interferon-alpha (IFN) therapy induces feeding suppression that resembles anorexia. The hypothalamic glucose-sensitive neurons engage in feeding behavior. Coronal sections of rat brains, containing both the lateral hypothalamus (LH) and the ventromedial hypothalamus (VMH), as well as single-cell recordings were used to study the interaction between IFN and glucose-sensitive neurons. IFN suppressed the majority (78%) of LH neurons, while reduction in glucose concentration elicited excitation in the majority (85%) of the same neurons. The opposite effects were observed in the VMH, where IFN excited the majority of neurons (61%), and reduction in glucose concentration exerted the opposite effects in 64% of VMH recordings. Concomitant IFN and glucose reduction exhibited only the effects elicited by IFN, regardless of whether the glucose reduction caused excitation (LH) or suppression (VMH). This observation suggests that IFN causes anorexia by modulating the LH and VMH glucose-sensitive neurons. PMID- 9372299 TI - Deficits of gaze stability in multiple axes following unilateral vestibular lesions. AB - Abnormalities in the vestibulo-ocular reflex (VOR) after unilateral vestibular injury may cause symptomatic gaze instability. We compared five subjects who had unilateral vestibular lesions with normal control subjects. Gaze stability and VOR gain were measured in three axes using scleral magnetic search coils, in light and darkness, testing different planes of rotation (yaw and pitch), types of stimulus (sinusoids from 0.8 to 2.4 Hz, and transient accelerations) and methods of rotation (active and passive). Eye velocity during horizontal tests reached saturation during high-velocity/acceleration ipsilesional rotation. Rapid vertical head movements triggered anomalous torsional rotation of the eyes. Gaze instability was present even during active rotation in the light, resulting in oscillopsia. These abnormal VOR responses are a consequence of saturating nonlinearities, which limit the usefulness of frequency-domain analysis of rotational test data in describing these lesions. PMID- 9372302 TI - Intentional on-line control of propulsive forces in human gait. AB - In locomotion, the capability to control and modulate intentionally the propulsive forces is fundamental for the adaptation of the body's progression, both in speed and direction. The purpose of this experiment was to determine how human beings can achieve such control on-line. To answer this question, four subjects walking steadily were faced with a linear increase in resistance (impeding forward displacement), lasting 3 s, once per minute. At the end of the variation, the new resistance was maintained. There were two tasks; in both tasks, in the initial steady state, the subjects had to walk steadily at 1.3 m s 1. As the resistance increased, subjects were either required to maintain their walking speed (compensation task) or to let the walking speed and amplitude adapt freely (no-intervention task). This provided an estimate of the effects of the perturbation alone. Throughout the experiment, the stride frequency (114 step min 1) was fixed by a metronome. Subjects maintained their stride frequency on both tasks. In the no-intervention task, walking speed was 1.3 and 1 m s-1 under normal and high resistance respectively. In the compensation task, under high steady resistance, walking speed was maintained by an increase in the activation gain of the neuromuscular synergy: all recorded muscles increased their EMG activity, but without any change in the shape of their activation profile throughout the cycle. During the transitional phases, however, as the resistance began to increase, the walking speed decreased temporarily (-2%) before returning rapidly to its initial value. By contrast, at the end of the resistance increase, no such changes in speed were observed. During the transitional phases, the on line compensation for the resistance increase induced modifications in the shape of the activation burst in the medial gastrocnemius such that the transitional cycles clearly differed from the steady state cycles. The results observed in the compensation task suggest that the subjects used two different modes of control during steady states and transitional phases. In stable dynamic conditions, there appears to be an "intermittent control" mode, where propulsive forces are globally managed for the entire stance phase. As a result, no compensation occurred at the beginning of the perturbation. During the resistance increase, subjects appeared to switch to an "on-line control" mode in order to continuously adapt the propulsive forces to the time course of the external force, resulting in an observable compensation at the end of the resistance change. PMID- 9372303 TI - Study of the EEG phenomenon of high-frequency bursts in the neocortical electrical activity of dogs in the process of alimentary instrumental learning. AB - We studied the electroencephalographic (EEG) phenomenon of high-frequency (HF) bursts (within the limits of 60-170 cycle, 70-80 microV) in the electrical activity (EA) of the brain (1-200 Hz) of dogs in the process of alimentary instrumental conditioning. These bursts appeared at the stage of generalization in a number of neocortical areas in the interstimulus intervals at the background EA, which was at lower amplitudes (10-40 microV). Application of novel strategies developed by us to the primary analysis of EA realization (in particular, introduction of inhomogeneity factor and activation index) enabled estimation the amplitude-frequency inhomogeneity of EA, namely, HF bursts. The regional peculiarities of HF bursts were revealed by means of the technique, developed by us, that was based on expansion of the EA variations into a system of half-waves and construction of distribution maps on the basis of their parameters. The presented data verify our earlier findings obtained with the use of other techniques (fast Fourier transform analysis and factor analysis). These data testify to differential participation of cortical areas (even those that are within 3-5 mm of each other) in the spatiotemporal organization of potentials that is characteristic for a given learning paradigm. PMID- 9372304 TI - Neuronal activity of somatosensory cortex in a cross-modal (visuo-haptic) memory task. AB - Studies have shown that in the monkey's associative cerebral cortex, cells undergo sustained activation of discharge while the animal retains information for a subsequent action. Recent work has revealed the presence of such "memory cells" in the anterior parietal cortex (Brodmann's areas 3a, 3b, 1, and 2)--the early stage of the cortical somatosensory system. Here we inferred that, in a cross-modal visuo-haptic short-term memory task, somatosensory cells would react to visual stimuli associated with tactile features. Single-unit discharge was recorded from the anterior parietal cortex--including areas of hand representation--of monkeys performing a visuo-haptic delayed matching-to-sample task. Units changed firing frequency during the presentation of a visual cue that the animal had to remember for making a correct tactile choice between two objects at the end of a delay (retention period). Some units showed sustained activation during the delay. In some of them that activation differed depending on the cue. These findings suggest that units in somatosensory cortex react to visual stimuli behaviorally associated with tactile information. Further, the results suggest that some of these neurons are involved in short-term active memory and may, therefore, be part of cross-modal memory networks. PMID- 9372305 TI - A hypothalamic projection to the turtle red nucleus: an anterograde and retrograde tracing study. AB - It is well known that the reptilian red nucleus lacks a descending motor cortical input to the red nucleus, but has a well-developed cerebellar input. The present study was undertaken to determine whether there is a descending rubral input that originates from the hypothalamus. Using an in vitro preparation from the turtle, injections of neurobiotin into the red nucleus resulted in retrograde labeling of neurons in the suprapeduncular nucleus of the hypothalamus. Injections of either neurobiotin or fluorescein dextran into the suprapeduncular nucleus resulted in anterograde labeling of axons and terminal boutons in the red nucleus. The majority of these terminations appeared to lie in the medial part of the red nucleus. These data have implications for the potential control of the somatic motor system of reptiles by limbic system inputs. PMID- 9372306 TI - Morphological asymmetries of the tectum opticum in the pigeon. AB - Pigeons are visually lateralized with a dominance of the right eye. Due to the virtually complete decussation of the optic nerves in birds, a right eye superiority probably depends on a left brain hemisphere dominance. The aim of the present study was to analyze whether morphological asymmetries in the cross sectional area of perikarya can be found within the retina and the optic tectum. With an image-analyzing system the cross-sectional areas of the somata of retinal ganglion cells and tectal neurons were measured in the left and the right side under blind conditions. The results reveal significant morphological left-right differences, with cells in superficial layers 2-12 being larger on the left side while neurons in laminae 13-15 have larger somata in the right tectum. No retinal asymmetries could be revealed. Since pigeon embryos keep their head turned to the right within the egg, such that the right eye is stimulated by light shining through the shell, it is possible that the morphological asymmetries at the tectal level are induced by left-right differences in prehatching photic stimulation. This embryonic sensory asymmetry might lead to a higher activity level of right eye ganglion cells and to a larger amount of released neurotrophins in the left tectum. This in turn could exert the morphological effects on soma sizes in the superficial retinorecipient layers. PMID- 9372307 TI - British Inflammation Research Association meeting: metalloproteinases and inflammatory diseases, the Fielder Centre, Hatfield, UK, 18 April 1997. PMID- 9372308 TI - Inflammation Research Association meeting: the puzzle posed by cytokines lacking a signal sequence, New York Academy of Sciences, USA, 22 May 1997. PMID- 9372309 TI - Tissue injury in neutrophilic inflammation. AB - The exudation of neutrophils is the hallmark of a form of inflammatory response occurring after tissue colonization by invading bacteria or as an expression of various non-infectious diseases. All these diseases are characterized by a high risk of developing irreversible tissue injury. Neutrophil-endothelium interactions, activation-induced functional and structural changes of responding neutrophils, regulatory systems of neutrophil function, and oxidative-proteolytic pathways responsible for histotoxicity are reviewed here. Finally, perspectives for rational approaches to handle the development of tissue injury during neutrophilic inflammation are considered. PMID- 9372310 TI - Extravasation of leukocytes assessed by intravital microscopy: effect of thalidomide. AB - OBJECTIVE AND DESIGN: Thalidomide is very effective in the treatment of idiopathic aphthous stomatitis, characterized by recurrent focal intramucosal leukocytic vasculitis. The mode of action of thalidomide in this clinical entity may include inhibition of the extravasation of leukocytes. Therefore, we studied the effect of thalidomide on different steps of leukocyte migration by intravital microscopy. MATERIAL: Male Syrian golden hamsters were used. TREATMENT: Leukocyte migration in buccal mucosa of the hamster cheek pouch was elicited by the local application of lipopolysaccharide (LPS, 20 micrograms/ml) or murine tumor necrosis factor-alpha (muTNF-alpha, 10 ng/ml). (+)-Thalidomide (20-200 mg/kg i.p.) was administered 60 min before the local application of LPS or muTNF-alpha. Dexamethasone (2 x 1.0-10 mg/kg i.p.) was administered 18 h and 60 min before topical LPS application. METHODS: The numbers of rolling, firmly adherent and migrating leukocytes were estimated by intravital microscopy up to 165 min after the topical applications of LPS or muTNF-alpha and evaluated by an interactive image analysis software. RESULTS: Thalidomide (20-200 mg/kg i.p.) dose dependently inhibited LPS-stimulated perivenular leukocyte migration by up to 87 +/- 5% and muTNF-alpha-induced leukocyte migration by up to 78 +/- 4%. Dexamethasone (2 x 1.0-10 mg/kg i.p.) inhibited LPS-stimulated leukocyte migration by up to 85 +/- 13%. (+)-Thalidomide (200 mg/kg i.p.) inhibited LPS stimulated rolling by 80 +/- 5% and reduced the number of firmly adherent leukocytes by about 40%. Dexamethasone (2 x 10 mg/kg i.p.) did not reduce the number of rolling leukocytes but inhibited leukocyte adherence by 72 +/- 9%. CONCLUSIONS: These results show that (+)-thalidomide predominantly inhibits leukocyte rolling and thus differs from the glucocorticoid dexamethasone. The inhibition of LPS- or muTNF-alpha-induced leukocyte extravasation by thalidomide may account for some of its clinical activities. PMID- 9372311 TI - Effects of ropivacaine on eicosanoid release from human granulocytes and endothelial cells in vitro. AB - OBJECTIVE: To examine the effects of ropivacaine, currently being investigated for treatment of ulcerative colitis, on the release of arachidonic acid metabolites. MATERIAL: Human granulocytes and endothelial cells. TREATMENT: Ropivacaine, lidocaine, hydrocortisone, 5-aminosalicylic acid or acetylsalicylic acid (10-1000 microM). METHODS: Leukotriene B4, 5-hydroxyeicosatetraenoic acid, 6 keto PGF1 alpha and 15-hydroxyeicosatetraenoic acid were measured using immuno assays. Wilcoxon signed rank test was used for statistical calculations. RESULTS: Ropivacaine dose-dependently inhibited zymosan-induced release of leukotriene B4 and 5-hydroxyeicosatetraenoic acid whereas the release after ionophore stimulation was not affected. Ropivacaine was more potent than 5-aminosalicylic acid but less potent compared to hydrocortisone. Ropivacaine had only a weak inhibitory effect on the release of 15-hydroxyeicosatetraenoic acid from zymosan- or ionophore-stimulated cells. In contrast to hydrocortisone and 5-aminosalicylic acid, ropivacaine only weakly affected the release of 6-keto PGF1 alpha after stimulation with thrombin. CONCLUSIONS: The inhibited release of 5-lipoxygenase products may account for some of the anti-inflammatory effects of ropivacaine seen in the treatment of ulcerative colitis. PMID- 9372312 TI - The effect of naloxone on basophil histamine release from dialyzed patients. AB - OBJECTIVE AND DESIGN: Naloxone had been shown to be effective in relieving pruritus of dialyzed patients. In order to determine the mechanism by which this is accomplished, we studied its effect on histamine release from white blood cells taken from this group. SUBJECTS: We compared 12 dialyzed patients (before and after dialysis) and 12 healthy controls. METHODS: The effect of naloxone (5 x 10(-3) M) on histamine release from the subjects' white blood cells was measured following anti-IgE + IL3 and TPA administration. RESULTS: The white blood cells of dialyzed patients had a high degree of histamine release compared to the healthy controls. Neither dialysis nor the patient's plasma affected this release. Naloxone markedly inhibited histamine release from white blood cells when stimulated with anti-IgE + IL3 or with TPA. CONCLUSIONS: We concluded that naloxone may have a beneficial effect in treating dialyzed patients suffering from pruritus, probably by inhibiting histamine release. PMID- 9372313 TI - Immunohistochemical characterization of HSP, alpha-MSH, Merkel cells and neuronal markers in acute UV dermatitis and acute contact dermatitis in vivo. AB - OBJECTIVE: To study the immunoneurocrine network in inflammatory dermatoses, we investigated histochemically acute UV and acute contact dermatitis. METHODS: Antibodies were applied to frozen and paraffin specimens of human skin after irradiation (n = 10), to positive patch tests (n = 10) and controls (n = 10) against: HSP 70, 72, 27, neuronal polypeptides (alpha-MSH, NSE, bombesin, PGP 9.5, NGF, NGF-R) and intermediate filaments (peripherin, NF 200, CK 19, 20). RESULTS: HSPs and alpha-MSH were upregulated in UV dermatitis in the epidermis compared to contact dermatitis and normal skin. Sunburn cells did not express HSPs or alpha-MSH in UV dermatitis. Neuronal markers and HSP 27 labeled more nerve fibers in UV than in contact dermatitis, except the increased staining for NGF, NGF-R and alpha-MSH in nerve fibers in contact dermatitis. In UV dermatitis, 50% of Merkel cells were suprabasal, but in contact dermatitis, basal, rounded and reduced in number. CONCLUSIONS: Merkel cells, HSPs and markers of neuroinflammation are of different importance in UV and contact dermatitis in vivo. PMID- 9372314 TI - Can a serotonin type 3 (5-HT3) receptor antagonist reduce experimentally-induced itch? AB - BACKGROUND: Serotonin type 3 (5-HT3) receptor antagonists have been reported to be a novel therapeutic principle for the treatment of cholestatic and uremic pruritus. OBJECTIVE: To determine the antipruritic effect of a 5-HT3 receptor antagonist (tropisetron) on histamine and serotonin-induced itch under experimental conditions in comparison to native skin and after pretreatment with an orally applied antihistamine (cetirizine). METHODS: Histamine and serotonin were iontophoretically applied in 10 healthy volunteers. Wheals and flares were planimetrically evaluated. Itching and burning sensations were entered on a scale over 24 min. The examination also comprised alloknesis, elicitation of perifocal itch sensation by usually non-itching (e.g. mechanical) stimuli. RESULTS: Tropisetron did not have any significant influence on histamine-induced reactions but could significantly reduce serotonin-induced flares. Cetirizine led to a significant reduction of all histamine-induced parameters and abolished serotonin induced wheals. CONCLUSIONS: Serotonin has an own pruritic potency and does not only act over histamine containing mast cells. The antipruritic effect of tropisetron reported in cholestatic and uremic pruritus could not be verified in healthy persons under experimental conditions. PMID- 9372315 TI - Simultaneous HPLC determination of metabolites of the inflammatory cascade. AB - OBJECTIVE: A model approach is presented to the in vivo inflammation cascade, in which the activities of key enzymes (phospholipase A2 [3.1.1.4], prostaglandin synthase [EC 1.14.99.1], and lipoxygenases [EC 1.13.11.12]) are determined simultaneously in a single in vitro assay. METHODS AND RESULTS: Detection of phospholipids (up to 50 pM) and arachidonic acid (up to 33 pM) is attained with high sensitivity and without radiolabelling using a SEDERE light scattering detector. CONCLUSIONS: Thus, in combination with a diode array UV-detector, lipids, prostaglandins, HETEs and other metabolites of the inflammation cascade can be determined with high efficiency using a reversed phase-high performance liquid chromatograph equipped with two highly sensitive detectors in series. PMID- 9372316 TI - Dapsone hydroxylamine inhibits the LTB4-induced chemotaxis of polymorphonuclear leukocytes into human skin: results of a pilot study. AB - OBJECTIVE: Dapsone (4,4'diaminodiphenylsulfone) is effective in treating leprosy, chronic inflammatory conditions and opportunistic infections in HIV patients. By the oral route, the sulfone is metabolized to monoacetyldapsone (MADDS) and dapsone hydroxylamine (DDS-NOH). We have addressed the question as to whether these dapsone metabolites have anti-inflammatory properties of their own in vivo. TREATMENT AND METHODS: After two weeks topical pre-treatment with MADDS (1%), DDS NOH (1%) and clobetasol proprionate (CP; 0.05%) dissolved in acetone, as a reference, 10 ng leukotriene B4 (LTB4) were applied on the upper arms of eight healthy volunteers. After 24 h, biopsies were taken and the polymorphonuclear leukocytes (PMN) were quantified fluorometrically using elastase as marker enzyme. RESULTS: MADDS did not show any inhibitory activity on trafficking of PMN compared to the corresponding control and nontreated area (untreated: 790 +/- 450 PMN/10 micrograms skin; p > 0.05, acetone: 840 +/- 578 PMN/10 micrograms skin; MADDS: 1099 +/- 556 PMN/10 micrograms skin), whereas DDS-NOH caused a statistically significant inhibition of PMN accumulation as did the reference CP (DDS-NOH: 128 +/- 143 PMN/10 micrograms skin; CP: 86 +/- 131 PMN/10 micrograms skin, p < 0.01). CONCLUSIONS: These results indicate that DDS-NOH has anti inflammatory potential which might contribute to the effectiveness of dapsone therapy. PMID- 9372317 TI - Effects of retinoids on the generation of neutrophil-derived reactive oxygen species studied by EPR spin trapping techniques. AB - OBJECTIVE: To study the potential efficacy of retinoids on granulocytes with regard to their role in inflammatory dermatoses. METHODS: We investigated the in vitro effect of acitretin and isotretinoin on the generation of reactive oxygen species (ROS) by stimulated human neutrophils using EPR spin trapping techniques. RESULTS: The effects of the two retinoids on ROS generation by neutrophils were different. Acitretin increased the generation of hydroxyl radicals, whereas isotretinoin showed an antioxidant activity against the superoxide anion. CONCLUSIONS: Our study demonstrates retinoid type-dependent effects on ROS production by stimulated neutrophils. PMID- 9372318 TI - Cyclic nucleotide-induced migration of electropermeabilized neutrophils: the effect of phosphodiesterase-resistant analogues. AB - OBJECTIVE: To study the effect of cyclic nucleotides and PDE-resistant cyclic nucleotide analogues on neutrophil migration. METHODS: Migration of electropermeabilized neutrophils in Boyden chambers in vitro. RESULTS: Addition of cyclic AMP inhibited migration of electropermeabilized neutrophils in the presence of cGMP, relative to the level of migration in the presence of cGMP alone. However, when cGMP was replaced with 8-pCPT-cGMP or Sp-cGMPS, analogues of cGMP which are not degraded by phosphodiesterases, cAMP synergistically enhanced migration. In contrast, migration in the presence of the phosphodiesterase resistant cAMP analogue, Sp-cAMPS, was not enhanced by addition of cGMP. CONCLUSIONS: Taking into account reports in the literature which show that cGMP hydrolysing activity can be enhanced by the catalytic subunit of cAMP-dependent protein kinase, it is hypothesized that breakdown of cGMP in neutrophils may be modulated via cAMP. PMID- 9372319 TI - Transcellular labelling of activated retinal microglia following transection of the optic nerve. AB - OBJECTIVES AND METHODS: A fluorescence and electron microscopical approach, based on the transection of the rat optic nerve and the axotomy-induced transcellular labelling of activated retinal microglial cells, using the carbocyanine dye 4Di 10ASP, was employed to monitor phagocytosis in the injured central nervous system. After survival times ranging between two days up to three months, retinal flat-mounts were inspected and photoconverted. RESULTS: Fluorescence microscopy revealed that within a few days microglia became transcellularly stained due to the phagocytosed 4Di-10ASP-labelled neuronal debris. Ultrastructural analysis confirmed that marked ganglion cell-derived material was incorporated into phagosomes of various sizes. Though immediate phagocytic intake was not observed, the nature of the detected phagosomes suggests that small fractions of degenerated neurons are incorporated. CONCLUSIONS: The approach presented, utilizing function-dependent transcellular fluorescent labelling of phagocytic microglia, might enrich further experimental studies of glia-neuron interactions in the injured nervous system. PMID- 9372320 TI - Enhanced expression of ICAM-1 (CD 54) in human skin wounds: diagnostic value in legal medicine. AB - OBJECTIVE: It was the aim of this study to characterize the vitality and the age of skin wounds by verifying the presence of ICAM-1. MATERIAL: 132 intravital human skin wounds (time since injury 15 min-19 days) were investigated by immunohistochemistry. The samples were taken either after surgical treatment of the wounds or from autopsy cases. METHODS: CD 54 was detected in paraffin sections by monoclonal antibodies after an autoclaving pretreatment using the ABC peroxidase technique. RESULTS: In samples of uninjured skin (n = 30), ICAM-1 appeared at a low concentration on keratinocytes and the endothelial cells of blood vessels. In injured skin, an increase in the surface expression was found to occur initially after a post-trauma interval of 2 h. The evaluation was made on a semiquantitative basis. A moderate to strong ICAM-1 expression occurred in 80% of the wounds investigated. CONCLUSIONS: The expression of ICAM-1 correlates with the degree of wound inflammation, which may be considered as an early evidence of the vitality of the wound. PMID- 9372321 TI - Geriatrics and longevity sciences in Japan. PMID- 9372322 TI - Renin/angiotensin/aldosterone system in malignant hypertension. PMID- 9372323 TI - Desquamative interstitial pneumonia: an idiopathic interstitial pneumonia with a possibility of spontaneous regression. PMID- 9372324 TI - Risk of extra-intestinal manifestations in outbreaks of salmonellosis. PMID- 9372325 TI - Differentiation of vasospastic angina from noncardiac chest pain by history and coronary risk factors in patients with chest pain at rest. AB - To determine the efficacy of the medical interview and the coronary risk factor profile in differentiating vasospastic angina from other causes of chest pain, we examined 59 patients who underwent diagnostic coronary angiography with selective intracoronary injection of acetylcholine. In the medical interview, a questionnaire on the characteristics of chest pain and additional symptoms was given. We examined coronary risk factors from laboratory tests, life history, and physical examination. Chest pain accompanied by cold sweat and occurring in the early morning was the only significant discriminating information; the location of pain and the duration were not discriminating. Classic coronary risk factors did not differ between vasospastic angina and noncardiac chest pain except for gender. We conclude that history taking is the most important means to distinguish vasospastic angina from other causes of chest pain. PMID- 9372326 TI - Effect of smoking on the serum concentration of erythropoietin and granulocyte colony stimulating factor. AB - Smoking is the most common cause of secondary polycythemia and may induce leukocytosis. We studied the relationship between hematopoietic growth factors and erythrocytosis and leukocytosis. Two sets of healthy male volunteers, consisting of 177 and 202 (age: 19-59 years) were each divided into four groups according to whether or not they smoked at least one package daily and their leukocyte count. Serum erythropoietin (Epo) concentration and granulocyte-colony stimulating factor (G-CSF) concentration were measured in the 177 and 202 volunteers, respectively. The mean serum Epo concentration was lower in smokers than in nonsmokers (p = 0.01 in the subjects without leukocytosis and p = 0.107 in those with leukocytosis, respectively). After 3 smokers stopped smoking, the Epo concentration increased 2 weeks later, and remained constant for 20 weeks. Smokers tended to have a higher mean serum G-CSF concentration than nonsmokers in the subjects without leukocytosis. Neither Epo nor G-CSF is the main etiology of smokers' polycythemia, and Epo production may be down-regulated by an elevated red-cell volume. PMID- 9372327 TI - Elevated sialyl Lewis X-i antigen levels in pleural effusions in patients with carcinomatous pleuritis. AB - The levels of sialyl Lewis X-i antigen (SLX), which is one of the cancer associated carbohydrate antigens, were evaluated in 83 malignant and 46 benign pleural effusions. SLX levels in pleural effusion due to lung adenocarcinoma were significantly higher than those due to benign diseases (p < 0.0001), lung cancer other than adenocarcinoma (p = 0.0052), and adenocarcinoma originating from other organs (p = 0.0492). According to receiver operating characteristic (ROC) curve analysis, the optimal cut-off level in the discrimination between malignant and benign pleural effusions was 92 U/ml, which gave a sensitivity of 57.1% and a specificity of 77.8%. The cut-off level of pleural effusion in patients with carcinomatous pleuritis might be higher than that of serum (38 U/ml). PMID- 9372328 TI - Neurological manifestations of primary Sjogren's syndrome in Japanese patients. AB - The neurological manifestations of twenty-one Japanese patients with Sjogren's syndrome (SjS) were evaluated. All patients were women, and sixteen of the twenty one cases (76%) demonstrated objective abnormal neurological symptoms, the most frequently observed of which was trigeminal neuropathy (50%). Multiple mononeuropathy was seen in almost one-third of the examined cases (31%). Central nervous system (CNS) involvement was observed in three cases (14%). All of these values differed greatly from those previously reported. Therefore, this study revealed characteristic features of Japanese SjS and also implied the existence of different immunopathological mechanisms associated with SjS in Japanese patients. PMID- 9372329 TI - Molecular typing of methicillin-resistant Staphylococcus aureus by polymerase chain reaction: distribution of the typed strains in hospitals. AB - Three methods for molecular typing of methicillin-resistant Staphylococcus aureus using polymerase chain reaction (PCR) were compared. The method which amplified the variable number of tandem repeat of dru sequences grouped the isolates into six types. Whereas, the method examining restriction fragment length polymorphism of coagulase gene and the method using arbitrarily primed-PCR showed poor diversity in typing. We investigated the distribution of dru types in two hospitals. Obvious concentration of a type in one ward was not recognized in our hospital. In the other hospital, a rare type was detected from the inpatients in the pediatrics ward. It suggested that the infection was an epidemic. We also found that some patients were infected with more than two strains. Even if two isolates show the same type, it does not necessarily mean that they originated from one clone. However, this method brings meaningful information on nosocomial infection, more easily than other genotyping. PMID- 9372330 TI - Malignant hypertension in a patient with primary aldosteronism with elevated active renin concentration. AB - A 40-year-old male, with a past history of hypertension but receiving no medical treatment, was referred. He manifested malignant hypertension (190/130 mmHg; Keith-Wagener III), renal dysfunction (serum creatinine, 3.8 mg/dl), and elevated plasma aldosterone (450 pg/ml) and active renin concentration (ARC, 104 pg/ml). His blood pressure was controlled with multiple antihypertensive agents and ARC thus decreased (4.3 pg/ml), but aldosterone remained elevated. Abdominal magnetic resonance imaging (MRI) revealed a right adrenal adenoma, and aldosterone producing adenoma was confirmed by adrenal venous sampling. Primary aldosteronism very rarely develops to malignant hypertension, and even in that case ARC is suppressed. Therefore this is a rare case of primary aldosteronism complicated with malignant hypertension and high ARC. PMID- 9372331 TI - Torsades de pointes complicating pentamidine therapy of Pneumocystis carinii pneumonia in acute myelogenous leukemia. AB - Pentamidine isethionate induced torsades de pointes in a 33-year-old woman with acute myelogenous leukemia. This is the first report of Pentamidine-induced torsades de pointes in Japan for over ten years. On the 4th day of intravenous pentamidine for Pneumocystis carinii pneumonia, asymptomatic sinus bradycardia was noted with QT interval prolongation, and torsades de pointes were revealed on the 8th day. Although torsades de pointes was dissolved with discontinuation of the intravenous pentamidine and administration of magnesium sulfate, sinus bradycardia and prolonged QT interval persisted. Ventricular pacing resulted in no arrhythmia and normalization of the QT interval on the 10th day after discontinuation of pentamidine. Careful monitoring of the electrocardiogram should be carried out during intravenous pentamidine therapy. PMID- 9372332 TI - Serum interleukin-5 levels in a case with allergic granulomatous angiitis. AB - A 50-year-old woman with allergic granulomatous angiitis (AGA) presented with an elevated serum interleukin-5 (IL-5) level upon admission to a hospital. Administration of prednisolone showed marked improvement of asthmatic symptoms, reduced eosinophil counts of peripheral blood, and normalized serum IL-5 levels. This is the first report describing an elevated serum level of IL-5 in AGA. The present findings suggest that IL-5 is involved in the pathogenesis of AGA. PMID- 9372334 TI - Ethanol sclerosis: one of the best treatments for thymic cyst in very elderly patients? AB - An 83-year-old female patient with a giant thymic cyst that was successfully treated by percutaneous aspiration and ethanol injection. The patient had complained of coughing and chest discomfort for several years. A chest X-ray film revealed the shadow of a large abnormal mass in the anterior mediastinum. We diagnosed it as a thymic cyst. The patient refused surgery because of her age. We chose a less invasive therapy, namely, ethanol sclerosis of the cyst. The cyst was successfully treated without any complications, and no recurrence was found at the one-year follow-up. This therapy may be one of the best treatments for thymic cysts, especially in very elderly patients. PMID- 9372335 TI - Direct intracerebral invasion from skull metastasis of large cell lung cancer. AB - A 56-year-old Japanese woman was referred to us for the treatment of lung cancer. On admission, the patient showed multiple bone metastases, including the skull, without brain metastasis. During chemoradiotherapy for the primary tumor and bone metastasis involving the thoracic spine, she suffered a fatal intracerebral hemorrhage. Since the patient had no risk factors for intracerebral hemorrhage, the skull bone metastasis was thought to be responsible for this event. At autopsy, penetration of the metastatic tumor from the skull bone into the dura, with direct invasion of the brain tissue, was confirmed histologically. A hematoma also was identified at the same site adjacent to the skull bone metastasis. To our knowledge, direct tumor invasion to the brain from a skull metastasis of non-small cell lung cancer has not been previously reported. PMID- 9372333 TI - Malignant lymphoma involving the penis following malignant pleural mesothelioma. AB - A 74-year-old man who had been diagnosed with malignant mesothelioma developed malignant lymphoma of B-cell origin involving the penis. He had a history of occupational exposure to asbestos as a construction worker. The association of malignant mesothelioma with lymphoma is rare, and the possibility of asbestos exposure as a common etiology is discussed. The intense stimulation of B lymphocytes and decreased T lymphocyte activity in asbestos-exposed populations may result in development of B-cell malignancies. Though the relationship between asbestos exposure and malignant mesothelioma is firmly established, the relationship between asbestos exposure and lymphoma remains to be investigated. PMID- 9372336 TI - L-Myc overexpression and detection of auto-antibodies against L-Myc in both the serum and pleural effusion from a patient with non-small cell lung cancer. AB - Non-small cell lung cancer patient was found to have auto-antibodies against L Myc in both the serum and pleural effusion. The titer of anti-L-Myc antibodies was higher in the pleural effusion than in the serum. Overexpression of L-Myc without DNA amplification was observed in the tumor cells. L-Myc antigen was not detected in either the serum or the pleural effusion. Anti-nuclear antibodies were also detected in both the serum and pleural effusion, although this patient did not have collagen-vascular disease. PMID- 9372337 TI - Spontaneous remission of desquamative interstitial pneumonia. AB - We report a case of spontaneous remission of desquamative interstitial pneumonia (DIP) in a 50-year-old male. The histological diagnosis of DIP was based on open lung biopsy. A chest X-ray revealed reticulo-nodular shadows in the bilateral lung fields, and the patient had mild dyspnea on exertion. Without treatment, these shadows decreased gradually and disappeared after several months. The patient recovered completely within one year, and recurrence of the disease has not been observed for 4 years. Recently, DIP has rarely been described, and the spontaneous remission of DIP has not been reported since Carrington et al in 1978 (1). PMID- 9372338 TI - Malignant solitary fibrous tumor arising in the right buttock associated with metastatic parietal pleural and intrapulmonary tumors in addition to pleural effusion. AB - A malignant solitary fibrous tumor arising in the right buttock associated with metastatic parietal pleural and intrapulmonary tumors and pleural effusion was found in a 59-year-old man. A chest computed tomogram revealed three tumors attached to the parietal pleura with rib destruction, and a tumor in the left lower lung field. Histologically, the tumors of the buttock and parietal pleura were characterized by proliferation of bundles of spindle-shaped or oval cells separated by wavy hyalinized collagen tissue with no expression of cytokeratin, S 100 protein, muscle actin or epithelial membrane antigen, but these cells weakly expressed CD34 and strongly expressed vimentin. PMID- 9372339 TI - High-dose etoposide treatment for CNS involvement in a patient with primary non Hodgkin's lymphoma of the breast. AB - A 46-year-old man was referred to us for treatment of non-Hodgkin's lymphoma (NHL; diffuse large immunoblastic B cell type), which had initially developed in the breast. He was treated with five courses of chemotherapy with CHOP (cyclophosphamide, adriamycin, vincristine, and prednisolone) and achieved a complete response. One year later, he noticed a gait disturbance. Magnetic resonance imaging (MRI) of the brain showed multiple nodules. A few abnormal cells were found in the cerebrospinal fluid (CSF). He was treated with high-dose etoposide (1,350 mg/ m2/course). After two courses, both the multiple nodular lesions in the brain and the abnormal cells in the CSF were resolved. High-dose etoposide is effective for CNS involvement by NHL. PMID- 9372340 TI - Cerebellar ataxia and peripheral neuropathy due to chronic bromvalerylurea poisoning. AB - A patient with chronic bromvalerylurea poisoning showed cerebellar ataxia and peripheral neuropathy. The patient was a 42-year-old Japanese man who developed consciousness disturbance, diplopia, slurred speech, ataxia and gait disturbance after having taken bromvalerylurea for ten years. Magnetic resonance imaging revealed atrophy of the cerebellum and pontine tegmentum. An electrophysiological study revealed decreased motor nerve conduction velocity and amplitude of compound muscle action potentials of the right tibial nerve. Histological findings of the left sural nerve indicated a slightly decreased large myelinated fiber diameter, which suggested chronic axonal damage. PMID- 9372341 TI - Probable post-influenza cerebellitis. AB - The nucleoprotein (NP) gene of type B influenza virus was detected by reverse transcription polymerase chain reaction (RT-PCR) from the cerebrospinal fluid (CSF) of a patient presenting with ataxia due to cerebellitis. The CSF was obtained 7 and 9 weeks after flu syndrome occurred, suggesting persistence of viral genes in the central nervous system (CNS). Although an unusually high serum hemagglutination inhibition (HI) titer against influenza virus B was noted, HI titers of the CSF were not elevated. PMID- 9372343 TI - Quality assurance in dermatology--the development of a framework. PMID- 9372344 TI - Leptin levels in obesity. PMID- 9372342 TI - Fatality due to severe Salmonella enteritis associated with acute renal failure and septicemia. AB - A 66-year-old man was hospitalized for abdominal pain and diarrhea of more than 10 times a day. He had been under regular medication with prednisolone for rheumatoid arthritis. On admission, laboratory data and clinical examination indicated inflammation, dehydration, acute renal failure with a high level of serum musculogenic enzyme (creatine kinase), and ileus. Salmonella enteritidis was isolated from his fecal and blood samples. The patient died within 24 hours after admission, and autopsy showed hemorrhagic necrotic enteritis localized to the ileum. Enterocolitis due to Salmonella enteritidis, which is usually an acute self-limited gastrointestinal illness, may occasionally be a serious and lethal disease. PMID- 9372345 TI - Dermatoses among Brazilian HIV-positive patients: correlation with the evolutionary phases of AIDS. AB - BACKGROUND: The presence of dermatoses is very common in Acquired Human Immunodeficiency Syndrome (AIDS). The present study was undertaken to correlate the various dermatoses with the evolutionary phases of AIDS. METHODS: We examined 223 HIV-infected patients older than 13 seen at the University of Sao Paulo, Faculty of Medicine of Ribeirao Preto, from 1989 to 1993. Patients were divided according to the CDC classification and assigned to groups I, II and III (initial stages of AIDS) and to group IV (fully symptomatic stage of AIDS). RESULTS: The mean frequency of dermatoses detected in patients with AIDS was higher compared to the early phases of HIV infection. The most frequently detected dermatoses were, in decreasing order of occurrence, dermatoses of fungal etiology, and desquamating disorders, such as psoriasis, seborrheic dermatitis, xerosis, and viral dermatoses. CONCLUSIONS: A careful examination of skin and mucosae may be highly useful for the diagnosis of HIV infection. The number of dermatoses tended to increase during the more advanced stages of infection. PMID- 9372346 TI - Classic Kaposi's sarcoma in Greece: a clinico-epidemiological profile. AB - BACKGROUND: Classic Kaposi's sarcoma (CKS) is not uncommon in Greece with a reported incidence of 0.20 per 100,000 per year. METHODS: Epidemiological, clinical and histological features of all CKS cases, diagnosed in 'A. Sygros' hospital, Athens, Greece during the years 1989-1994, have been recorded and studied prospectively. RESULTS: During the five-year period studied, 66 CKS patients have been diagnosed in our hospital. Incidence among dermatologic patients was 2.11 per 10,000 patients examined, representing 1.35% of total skin malignancies. Patients' age at diagnosis ranged from 53 to 94 years (mean 72 +/- 8.8). The male to female ratio was 2.47:1. A high proportion of the patients were born in Peloponnesos (42.42%) and were residing in Athens (51.51%) or in Peloponnesos (24.24%). Nodules and/or plaques were the most frequent type of lesion, most commonly located on the feet (43.93%) or the hands (28.78%). Accompanying edema was seen in 51.51% of the patients. There were 16 stage I patients (24.24%), 40 stage II (60.60%), 0 stage III and 10 stage IV (15.15%). Involvement of visceral organs was detected in seven patients (10.60%), while 10 had lymph node involvement (15.15%) and three, involvement of the underlying bones (4.54%). Second primary malignancy was diagnosed in 6 cases (9.09%), most often of the reticuloendothelial system (83.33%). CONCLUSIONS: CKS in Greece exhibits some special characteristics, including older age of onset; lower male to female ratio; endemic clustering; disseminated skin disease at diagnosis, often accompanied by lymphedema; not unusual visceral or lymph node involvement and association with second malignancies. We suggest that CKS in Greece possibly represents a distinct endemic subtype of CKS. PMID- 9372347 TI - Seroprevalence study of HIV-I, HIV-II and HTLV-I among patients at the Dermato Venereology Clinic of the Lagos University Teaching Hospital. AB - BACKGROUND: Seroprevalence studies of HIV-I and HIV-II that have been reported in Nigeria were among commercial sex workers and blood donors. There are no data from STD patients and dermatologic patients. METHODS: A seroprevalence study of HIV-I, HIV-II and HTLV-I was prospectively conducted among STD clinic attendees and among patients with dermatoses which have been linked with HIV disease. The studies were done in 1992 and 1994. RESULTS: Some patients had more than one seropositive type. In 1992, the percentages of seropositive results to HIV-I, HIV II and HTLV-I were 31, 19 and 50, respectively, and in 1994 the percentages of HIV-I and HTLV-I were 65 and 35, respectively. CONCLUSIONS: Patients should be routinely screened for HTLV-I, in addition to HIV-I and HIV-II, among blood donors and also neurology clinic attendees in Nigeria. They should also be screened for retroviral infections when they present with dermatoses clinically suggestive of papular urticaria, onchodermatitis, or papulonecrotic tuberculids. PMID- 9372348 TI - Histopathologic features seen in cutaneous photoeruptions in HIV-positive patients. Military Medical Consortium for the Advancement of Retroviral Research (MMCARR). AB - BACKGROUND: There have been scattered reports of HIV+ patients with increased reactions to light as well as anecdotal reports of HIV+ patients with increased morbidity secondary to radiation therapy. METHODS: As a part of a military study of HIV+ patients, we followed 987 patients for cutaneous disease for 4 years. All patients were questioned on a periodic basis about increased sensitivity to light. These patients received a physical examination at each protocol visit, and they were given the opportunity to receive all their dermatologic care within the HIV clinic. Fourteen of the patients with photo-induced eruptions were evaluated clinically at the time of the eruption, and 11 of these were biopsied. RESULTS: Thirty-three of the patients reported photo-induced reactions unrelated to oral medications. Although sensitivity to light often began in the early stages of HIV disease, reactions became more severe and more chronic with disease progression. Histologic features varied from few to numerous apoptotic/necrotic keratinocytes within the mid to upper levels of the epidermis associated with a perivascular inflammatory infiltrate, to apoptotic/necrotic keratinocytes throughout an acanthotic epidermis with a lichenoid/interface infiltrate. CONCLUSIONS: Although the pathogenesis of these light reactions is not known, these reactions may be related to depletion of endogenous scavengers which results in increased oxidative stress and is modulated by the pattern of immune dysregulation and metabolic dysregulation induced by HIV disease. PMID- 9372349 TI - The effect of toenail onychomycosis on patient quality of life. AB - BACKGROUND: Onychomycosis is a common fungal infection of the toenails which has historically been regarded as a cosmetic problem. A previous study has suggested that this is not the case and that toenail and fingernail onychomycosis adversely impacts patient quality of life (QOL). METHODS: A survey was used to self-assess the physical symptoms and psychosocial dimensions of toenail onychomycosis in 93 patients. Positive responses scored one point each, and points were summed for each patient. RESULTS: Ninety-two per cent of patients reported experiencing negative psychosocial and/or physical effects. Forty-four per cent indicated that their toenails had a negative effect on their self-image, and 41% reported experiencing pain or discomfort as a result of onychomycosis. CONCLUSIONS: Toenail onychomycosis has a significant impact on the overall QOL of patients, and should be evaluated further to develop guidelines for total patient care. PMID- 9372350 TI - Onychomycosis in Hong Kong. AB - BACKGROUND: Onychomycosis in temperate countries has been studied extensively, but few data are available on its epidemiology in tropical countries. We performed a survey of patients seen in Hong Kong for the 8-year period from January 1987 to December 1994. METHODS: A retrospective study of the mycology laboratory records of patients attending the Government Dermatology Clinics was carried out. Nail samples examined included clippings, scrapings, and drillings. Microscopy was performed on all specimens. Sabouraud dextrose agar was used for culture. RESULTS: Out of a total of 2382 nail samples (1024 (43.0%) toe, 1148 (48.2%) finger, and 210 (8.8%) unspecified site) examined, 340 (14.3%) were microscopy positive; 165 (48.5%) of these were culture positive, including 160 (97%) with dermatophyte and/or yeast, and 5 (3%) with molds. Men were affected more in the < 19 and > 50 years age groups, whereas women were affected more in the 20-50 years age group. Women were affected significantly more than men with yeasts, dermatophytes occurred more during adolescence. Dermatophytes showed a high peak in late spring, although both dermatophyte and yeast cases peaked in the summer months. Dermatophytes (29.1%) occurred more commonly than yeasts (19.4%) in microscopy-positive onychomycosis cases in Hong Kong. Trichophyton rubrum was the commonest dermatophyte, and Candida spp, other than C. albicans, were the commonest yeasts. Mixed infections (5%) were uncommon. CONCLUSIONS: Dermatophytes are more important than yeasts as a cause of onychomycosis in Hong Kong. Changes in climatic conditions affect the prevalence of dermatophytes more than yeasts. PMID- 9372351 TI - Scrotal glans penis (glans penis plicatum) associated with scrotal tongue (lingua plicata). PMID- 9372352 TI - Cutaneous electron microscopic study of sclerodermia diffusa in childhood. PMID- 9372353 TI - Clinical considerations in digitate dermatosis. PMID- 9372354 TI - Two cases of pachydermodactyly. PMID- 9372356 TI - The role of macrophage migration inhibition factor in toxic epidermal necrolysis. PMID- 9372355 TI - Acquired cutis laxa associated with cutaneous angiocentric T-cell lymphoma. PMID- 9372357 TI - Increased cutaneous toxicity to ionizing radiation in HIV-positive patients. Military Medical Consortium for the Advancement of Retroviral Research (MMCARR). AB - BACKGROUND: There are reports of increased reactions in HIV-1+ patients to ultraviolet light sometimes in association with medication. In addition, there are also reports of increased morbidity associated with radiation therapy in HIV 1+ patients. METHODS: Three HIV-1+ patients developed cutaneous toxic reactions to radiation therapy; two with Kaposi's sarcoma (KS) and one with non-Hodgkin's lymphoma. CONCLUSIONS: Although the mechanisms which resulted in these reactions are not clear, they may be related to depletion of endogenous scavengers and may be accentuated by the pattern of immune dysregulation present in HIV-1 disease. PMID- 9372358 TI - Prevalence and epidemiology of unsuspected onychomycosis in patients visiting dermatologists' offices in Ontario, Canada--a multicenter survey of 2001 patients. AB - BACKGROUND: Questionnaire studies have been used to determine the prevalence of onychomycosis in the United Kingdom and Europe. One disadvantage of this methodology is that the patient self-diagnoses the onychomycosis. There have been very few large studies involving clinical examination of the nails of subjects, followed by mycological confirmation of the onychomycosis. We therefore determined the prevalence of onychomycosis in patients visiting dermatologists' offices in Ontario, Canada. METHODS: In a prospective, multicenter study, the finger- and toenails of all new patients presenting to dermatologists' offices were examined by a board-certified dermatologist. If there was clinical suspicion of onychomycosis, then nail samples were obtained for mycological examination at a central laboratory. Patients referred specifically for the management of onychomycosis were excluded. RESULTS: Toenails appeared abnormal in 455 (22.7%) of 2001 patients. Mycologically-confirmed pedal onychomycosis was present in 182 (9.1%) of the 2001 patients. The estimated value of the prevalence of onychomycosis in Ontario is 6.86% (95% confidence interval (CI): 5.8-8.0%), when corrected for age and sex of the general population using census data. Onychomycosis increased with age (P < 0.0001). The odds of males having onychomycosis was 84.3% greater than females of the same age (P = 0.0003). The distribution of organisms in the 141 patients with pedal onychomycosis who were culture positive was: dermatophytes 131 (92.9%), Candida species 4 (2.8%) and non dermatophyte molds 6 (4.3%). CONCLUSIONS: The prevalence of mycologically confirmed toenail onychomycosis was 9.1%, with the estimated prevalence in Ontario being 6.86%. The majority of patients with abnormal-appearing nails were unaware they might have onychomycosis, that it is infectious and potentially treatable, suggesting that there is potential for increased public awareness and education. PMID- 9372359 TI - Anti-inflammatory activity of antifungal preparations. AB - BACKGROUND: Although steroid/antifungal combination medications are used extensively, they are associated with potential disadvantages. Antifungal preparations possessing inherent anti-inflammatory activity, leading to rapid symptomatic relief while providing mycologic cure, would be very useful. OBJECTIVE: Our purpose was to investigate the anti-inflammatory activity of proprietary antifungal preparations in an in vivo, human experimental model. METHODS: Using a double-blind, controlled protocol, we assessed the comparative ability of antifungal preparations to suppress the expected delayed erythema response following in vivo human exposure to ultraviolet B (UVB) irradiation generated by a solar stimulator. RESULTS: Currently available allylamine preparations and ciclopirox olamine proved to be the most anti-inflammatory, while ketoconazole was intermediate in anti-inflammatory activity under these experimental conditions. These agents were superior to oxiconazole, econazole, and 2.5% hydrocortisone. CONCLUSIONS: Some antifungal preparations possess inherent anti-inflammatory activity, although the exact mechanism remains uncertain. PMID- 9372360 TI - Major landmarks in the history of urticarial disorders. PMID- 9372361 TI - Necrobiosis lipoidica diabeticorum and thyroid disease. PMID- 9372362 TI - Cardiac applications of video assisted thoracic surgery. AB - As experience with video assisted thoracic surgery (VATS) has grown, cardiac applications of VATS are being explored. Simple cardiac procedures including pericardiectomy and epicardial pacemaker lead placement are readily accomplished by VATS. More complex cardiac procedures are being investigated both in the laboratory and in the clinical arena. Totally endoscopic coronary artery bypass grafting has been successfully performed in the animal model. Modification of existing instrumentation and techniques has had an enabling benefit. The human experience consists of predominantly a video assisted minithoracotomy approach with some successful promise. More advanced procedures including minimally invasive valve replacement are also being explored. PMID- 9372364 TI - The current role of video-assisted thoracic surgery (VATS) in the overall practice of thoracic surgery. A review of 207 cases. AB - From December 1991 to June 1995, video-assisted thoracic surgery (VATS) was performed on 207 patients at the Medical Center of Delaware with minimal complications and no mortality. A definitive diagnosis was made in all patients. Results with VATS procedures appear to be comparable to those with the standard open technique. Operating time was comparable to that with the open technique. Length of stay and pain and suffering were dramatically reduced compared with the open technique. We now consider VATS to be the preferred procedure in the following conditions: 1. Undiagnosed pulmonary infiltrate in the non-ventilator dependent patient. 2. Indeterminate pulmonary nodule. 3. Undiagnosed disease of the pleural space. 4. Recurrent or persistent pneumothorax. 5. Mediastinal or pericardial cystic tumors. 6. Thoracic sympathectomy. 7. Selected patients requiring esophagocardiomyotomy. The utilization of VATS for resection of a pulmonary mass in patients with compromised pulmonary status (i.e., FEV < 1) is being studied. PMID- 9372363 TI - Thoracoscopy for trauma. AB - Thoracoscopy is currently undergoing a revival in the surgical world. As the role of thoracoscopy increases in the general thoracic surgery arena, the indications for the technique in the care of trauma patients is also expanding. Trauma surgeons are investigating both diagnostic and therapeutic indications. Penetrating thoracoabdominal trauma is a proven indication to evaluate the diaphragm for possible violation. Investigation of thoracic hemorrhage with identification of bleeding sites, evacuation of hemothorax, and control of ongoing blood loss have all been reported successfully via the thoracoscope. Recent reports have sited isolated patients were diaphragmatic repair has been accomplished with endoscopic techniques. Other indications await the improvement of techniques and instruments, and the imagination of future surgeons. PMID- 9372365 TI - Complications and contraindications of thoracoscopy. AB - In many instances surgical intervention in the chest has been replaced by the minimally invasive thoracoscopic or VATS approach. With such a technique there are disadvantages, complications and contraindications that develop or exist. Disadvantages include the loss of tactile sensation and the cost of the procedural equipment. Absolute contraindications include a fused lung, markedly unstable patient, shock or cardiac arrest, and an individual unable to tolerate partial or complete unilateral collapse of the lung. Lesser contraindications include the patient with bleeding tendencies or under anticoagulant therapy. The few major complications we have seen include prolonged air leak, pulmonary atelectasis and respiratory failure, the "down" lung syndrome or retained secretions. Technical complications including inability to locate the lesion because of its small size, penetration of the lung or inadequate resection of a tumor with subsequent seeding of the tract through the pleural and chest wall have been reported. Major bleeding has not occurred in our institution. Mortality has been seen only in the preterminal malignancy patient. PMID- 9372366 TI - Malignant peritoneal mesothelioma. Case-report demonstrating pitfalls of diagnostic laparoscopy. AB - Patients with peritoneal mesothelioma present with abdominal distension and clinical syndrome of debilitating ascites. Cytology of the peritoneal fluid obtained by laparocentesis often does not result in a diagnosis. Laparoscopy with biopsy of peritoneal nodules is a valuable method by which a histological diagnosis is established. However laparoscopy can greatly complicate the management of peritoneal mesothelioma by facilitating tumor dissemination to port sites. The patient presented was treated with cytoreductive surgery and perioperative intraperitoneal chemotherapy. Although palliation of intra abdominal tumor and ascites was achieved, port sites-disease required extensive resection of the abdominal wall. Our experience with this patient suggests that if a malignant source of ascites is suspected and a diagnosis is not obtained by paracentesis, laparoscopy should be used to establish a diagnosis. However, trocars should only be placed along the midline of the abdominal wall so that port sites can be excised at the time of cytoreductive surgery. This diagnostic strategy is applicable to the majority of patients undergoing laparoscopy when there is known or suspected intraabdominal malignancy. PMID- 9372368 TI - Gastro-esophageal isoperistaltic bypass in the palliation of irresectable thoracic esophageal cancer. AB - METHODS: The authors retrospectively review 22 patients with irresectable esophageal cancer in whom an isoperistaltic substernal gastric esophagogastric bypass was performed. RESULTS: After the operation eighteen patients (82%) regained normal swallowing. Seven patients developed anastomotic stenosis that was successfully treated in six by surgery or endoscopic dilatation. Two patients evolved with cervical fistulae until their death. As a whole, there was a statistically significant improvement in swallowing capability (p = 0.0352). Seventeen patients (77%) had postoperative complications, the most common being cervical fistulae (in 13.59%), pneumonia (in 10.45%) and anastomotic stenosis (in 7.32%). Postoperative morbidity was significantly associated with preoperative diseases and ASA class III (p < 0.05). There were three postoperative deaths (14%). Postoperative mortality was significantly related to severe malnutrition and preoperative associated disease (p < 0.05). CONCLUSIONS: The conclusion is that the procedure has acceptable morbidity and mortality for the population under consideration, permitting palliation of dysphagia in the majority of cases. PMID- 9372369 TI - Cardiac arrest during anesthesia in a teaching hospital. A 4 years survey. AB - METHODS: During the past 4 years, 48 cases of cardiac arrest occurred during anesthesia among a total of 104,600 cases of anesthesia at Mackay Memorial Hospital in Taipei. RESULTS: The incidence of cardiac arrest was thus about 0.046% (48/104,600), with the causative factors being anesthetic related in 21% (10/48) of cases, surgical factors in 19% (9/48) of cases and patient's pathological factors in 60% (29/48) of cases. Of these 48 patients, 34 died and 14 survived after cardiopulmonary resuscitation (CPR). Anesthesia contributed to death in 3 cases of a total of 104,600 cases of anesthesia giving an approximate incidence of 3/100,000. Two of these 3 cases were avoidable. PMID- 9372367 TI - Peritoneal cytology and its prognostic value in endometrial carcinoma. AB - BACKGROUND: There has been a controversy about the prognostic significance of positive peritoneal cytology in endometrial carcinoma. MATERIALS AND METHODS: Peritoneal cytology was obtained at the time of surgery, including systematic retroperitoneal lymph node dissection, in 114 patients. RESULTS: The incidence of positive peritoneal cytology was 35.1%. The 5-year survival rates of the stage IIIA and IIIC (FIGO, 1988) cases were 82.8% and 58.3%, respectively. In pathological stage I (the disease was histologically confined to the uterine corpus), there was no significant difference in 5-year survival rates between patients with and without positive peritoneal cytology. Though the patients in stage IIIA who had only positive peritoneal cytology were given no postoperative therapy unless they had extrauterine disease, no patients developed recurrence. In stages IIIC and IV, the prognosis was significantly poorer for patients with positive peritoneal cytology than for those with negative cytology. CONCLUSION: Positive peritoneal cytology is not an adverse prognostic factor endometrial carcinoma if disease is limited to the uterus. PMID- 9372371 TI - Evaluation of the clamshell incision for bilateral pulmonary metastases. AB - To treat bilateral pulmonary metastases during a single operation, simultaneous bilateral thoracotomy via median sternotomy is usually employed. With this approach, however, it is sometimes difficult to access lesions located on the dorsal side of the left lower lobe. We have explored the use of clamshell incisions for such difficult cases. From 1990 to 1995, we studied the use of clamshell incisions in 14 patients with bilateral pulmonary metastases. The average duration of surgery was 212 minutes, the average volume of intraoperative blood loss was 477 ml, and the average number of metastatic lesions extirpated was 23. The endotracheal tube could be removed immediately after the operation in 12 patients, while the remaining 2 patients, who underwent an extensive operation, needed 3 and 4 days of intubation. The arterial blood gas analysis on the first postoperative day for the former 12 patients was as follows: the average value of PaCO2 was 44.4 mmHg, and the average value of PaO2 was 140.4 mmHg (FiO2 = 0.4). None of the patients experienced severe pain or respiratory distress that impaired their daily activities due to continuous epidural anesthesia following surgery. The length of time from surgery to discharge was relatively short, averaging 22 days. We have not encountered any sternal override in our patients. Although we cannot ignore the biological behaviour of primary tumors when selecting a surgical approach, the clamshell incision seems to provide a useful means of thoracotomy when treating bilateral pulmonary metastases. We intend to use this approach in future, taking into careful consideration the indication of each individual case. PMID- 9372370 TI - Results of extended lymph node dissection for gastric cancer cases with N2 lymph node metastasis. AB - The therapeutic value of extended lymph node dissection (D2) for gastric cancer remains controversial. Limited lymph node dissection, however, leaves cancer cells in the second tier of nodes (N2) in patients with N2 metastasis. This retrospective study was, therefore, undertaken to clarify which patients would be most likely to benefit from D2 dissection, even with N2 metastasis. Two groups, N2 cases with (n = 40) and without (n = 24) the development of recurrence after curative surgery, were compared. Borrmann type IV and serosal invasion were significantly related to recurrence. The number of metastatic nodes did not differ significantly between the two groups. All (7/7) of the Borrmann type IV cases with N2 metastasis developed recurrence and died. However, one quarter (7/30) of the cases with serosal invasion and N2 metastasis showed no sign of recurrence. D2 dissection is a surgical treatment which offers the potential to cure gastric cancers, other than Borrmann type IV tumor, with N2 metastasis. PMID- 9372372 TI - New approaches in laparoscopically assisted radical vaginal hysterectomy. AB - BACKGROUND: To illuminate our new approaches in laparoscopically assisted radical vaginal hysterectomy. METHODS: Twenty-four women underwent laparoscopically assisted radical vaginal hysterectomies during the period from March 1994 to May 1995 in our institute. Indications for this surgery, including cervical carcinoma stage 1A to 2A, were the same as for abdominal radical hysterectomy. The procedure was performed under general endotracheal anesthesia through means of the technique of videolaparoscopy. Two new approaches were recruited in these procedures including using middle upper abdomen as the primary trocar site and using ureteral stent or illuminator as a ureter marker. RESULTS: All of these patients completed the procedures without exception. The mean hospital stay was 8.2 +/- 3.2 days. The average blood loss was 540 +/- 210 ml with a range from 100 to 1800 ml. Operating time was from 220 to 420 minutes with a mean time of 325 minutes. In all cases pelvic lymphadenectomy was performed without exception, yielding an average of 13.2 macroscopic nodes. Two of them metastatic lymph nodes were noted. No ureteral injury occurred after using the ureteral stent as a marker. CONCLUSIONS: In this preliminary result, using middle upper abdomen as the primary trocar site could provide the surgeon with a wider and familiar visual angle, thus making the pelvic or para-aortic lymphadenectomy much easier. Moreover, using the ureteral illuminator as a marker during unroofing the ureter laparoscopically is helpful to prevent the ureteral injury and facilitating the procedures in laparoscopically radical hysterectomy. PMID- 9372373 TI - Carcinoma of the pancreas: resection outcome at the University Hospital Kuala Lumpur. AB - BACKGROUND: Recent studies have demonstrated a reduction in the morbidity and mortality of pancreatic resection and improvement in the actuarial 5-year survival for patients with resected ductal adenocarcinoma. We reviewed the clinico-pathological characteristics of patients who underwent resection with curative intent for ductal adenocarcinoma of the pancreas between 1980 and 1993. METHODS: Resection with curative intent was performed on 236 of 1368 patients (17%) with pancreatic cancer admitted to the University Hospital Kuala Lumpur, Malaysia. Clinical, demographic, treatment, and pathological variables were analysed. The original pathological report for all cases was reviewed; non-ductal cancers were excluded. The head of the gland was the predominant tumour site (n = 204), followed by the body (n = 18), and tail (n = 14). Seventy-two percent of the patients underwent pancreaticoduodenectomies, 15% underwent total pancreatectomies, 10% underwent distal pancreatectomies, and 3% underwent distal subtotal pancreatectomies. RESULTS: Operative mortality was 3.4%. Median survival was 14.3 months after resection compared with 4.9 months if patients did not undergo resection (p < 0.0001). Twenty-four patients survived 5 years after surgery (10.2% overall actual 5-year survival rate). Six of the tumours were well differentiated, 10 were moderately differentiated, and 8 were poorly differentiated. Extra-pancreatic invasion occurred in 18 cases (75%), and perineural invasion was present in 20 cases (83%). Ten tumours exhibited invasion of duodenum, ampulla of Vater, and/or common bile duct, and another 2 tumours invaded the portal vein. Lymph node involvement by carcinoma was noted in 10 cases (42%). Twelve patients remain alive without evidence of disease at a median follow-up of 101 months (range, 82-133 months). Ten patients died of recurrent or metastatic pancreatic cancer in a period between 60 and 64 months. Two patients died at 82 and 84 months respectively, of metastatic lung cancer without evidence of recurrent pancreatic disease. CONCLUSIONS: This paper emphasises the grim prognosis of pancreatic ductal adenocarcinoma. Five-year survival cannot be equated to cure. Although pancreatectomy offers the only chance for long-term survival, it should be considered as the best palliative procedure currently available for the majority of patients. This emphasises the need for the development of novel and effective adjuvant therapies for this disease. PMID- 9372374 TI - CEA, TPA, CA 19-9, SCC and CYFRA at diagnosis and in the follow-up of anal canal tumors. AB - The authors evaluated serum CEA, TPA, CA19-9, SCC and CYFRA at diagnosis and in the follow-up of 18 anal canal tumors. Sensitivity at diagnosis was 38.8% for CEA, 55.5% for TPA, 16.6% for CA19-9, 50% for SCC and 5.5% for CYFRA. In the follow-up CEA showed 0% sensitivity and 73.3% specificity, TPA 33.3% sensitivity and 86.6% specificity, CA19-9 0% sensitivity and 80% specificity, SCC 0% sensitivity and 93.3% specificity, CYFRA 0% sensitivity and 100% specificity. The authors consider the usefulness of serum SCC and TPA at diagnosis of squamocellular anal cancer and of CEA in the diagnosis of cloacogenic tumors. Nevertheless these serum markers did not detect recurrences in the follow-up. PMID- 9372375 TI - Biliary enteric fistulas. AB - Thirty-one patients with biliary enteric fistula who were operated on over a 19 year period (1976-1994) with an incidence of 0.74% in all biliary tract operations were reviewed retrospectively to identify etiologic factors, types of fistulas, signs and symptoms, methods of diagnosis, management and prognosis of the cases. Most common symptoms were abdominal pain, nausea, vomiting and jaundice. Two patients had gallstone ileus. The majority of the patients had severe concomitant medical illnesses. The exact preoperative diagnosis of a biliary enteric fistula was established in only five (16%) patients. In 81% of the cases fistula was secondary to chronic calculous biliary tract disease. Postoperative complications included wound infection in six (19%), biliary fistula in two (6%) and erosive gastritis in one (3%) patient. Two patients died of intra-abdominal sepsis and two of cardiac failure, with an operative mortality of 13%. Early elective cholecystectomy is recommended to avoid complications of chronic calculous cholecystitis such as bilioenteric fistulas and their increased mortality and morbidity. PMID- 9372376 TI - Allopurinol dosage and effect on ischemia-reperfusion damage in elective and acute aortic surgery. AB - To study the effect of a safe dosage of allopurinol on ischemia-reperfusion damage following aortic surgery, 24 patients undergoing either elective or acute aortic reconstruction, were randomized to receive allopurinol or placebo, yielding four groups: elective/placebo (EP), elective/allopurinol (EA), acute/placebo (AP) and acute/allopurinol (AA). Blood concentrations of allopurinol, oxypurinol, uric acid, malondialdehyde, ascorbic acid, and 99mTc albumin were determined perioperatively. Adequate concentrations and biochemical activity of allopurinol and oxypurinol were obtained, without side-effects. Malondialdehyde did not increase perioperatively, but was significantly higher in acute surgery than in elective surgery intraoperatively. Yet, ascorbic acid levels and 99mTc-albumin disappearance were not different from groups EP and EA. No influence of allopurinol was found on malondialdehyde, ascorbic acid and 99mTc albumin. An influence of allopurinol may have been obscured, as patients in group AA were more hypotensive than in group AP. In conclusion, adequate allopurinol concentration can be obtained with a safe dosage in abdominal aortic surgery. Signs of ischemia-reperfusion injury were found in acute surgery, not in elective surgery. Therefore, further investigation on the clinical effect of allopurinol is only useful in acute aortic surgery. PMID- 9372377 TI - Breast conserving treatment versus modified radical mastectomy in Japanese patients with operable breast cancer. AB - From January, 1988 to October, 1995, 96 patients with operable breast cancer were treated by breast conserving treatment (BCT) including wide excision and axillary dissection followed by breast radiation. During the same period, 188 patients were treated by modified radical mastectomy (MRM) with or without breast reconstruction. In order to compare the survival of BCT and MRM groups, univariate and multivariate analyses were performed in this retrospective study. Univariate analysis revealed that the 5-year survival rates in the BCT and MRM groups were 97% +/- 2% and 87% +/- 3%, respectively (p < 0.05 with the Cox-Mantel test). However, the baseline variables were different between the groups. The adjusted Cox regression analysis revealed that the results of BCT were almost equivalent with those of MRM. Moreover, no breast recurrence was found in the BCT group. Therefore, it is suggested that our technique of BCT is as effective as modified radical mastectomy in treating operable breast cancer in Japanese patients. PMID- 9372378 TI - Gallbladder carcinoma: a 28 year experience. AB - BACKGROUND: Despite the fact that several studies have been conducted to demonstrate advancements in the treatment and prognosis of gallbladder carcinoma, no standard method of treatment has been identified or agreed upon. OBJECTIVE: The aim of this study were to review the presentation, staging, treatment and prognosis of subjects with cancer of the gallbladder at Howard University and its affiliated Institutions over the last three decades to see if there were any improvement in the survival. METHODS: A retrospective analysis of a 28 year experience at Howard University was performed. Patient gender, age, symptoms, signs, the diagnostic tests, pathology reports, operative and adjuvant treatments of each case were reviewed. A review of the English literature on the subject of gallbladder carcinoma covering the last twenty years using a Medlars search of the subject was also performed. An attempt was made to determine the utility of the various radiological tests used to diagnose and stage gallbladder, cancer. RESULTS: Patients with Stage I tumors using the Nevin classification had a 100% survival at 5 years. Patients with Stage V had 0% survival at 5 years. Stages II, III and IV had survivals of 51%, 12% and 10% respectively. The most common presenting symptom was abdominal pain which was present in 45% of cases. Gallbladder ultrasound studies had a sensitivity of 50% while the CT scanning had a sensitivity of 40% for disease detection. ERCP, when used, had a sensitivity of 75%. Radio and chemotherapy did not influence the survival of patients in this series. The most common surgical procedure performed was cholecystectomy with or without an associated hepatic resection for stage II and III, combined with adjuvant chemotherapy. CONCLUSIONS: The current prognosis of individuals with gallbladder carcinoma is dismal, nevertheless a slightly improvement over the last three decades has been achieved particularly regarding the sensitivity of the radiological tests to diagnosis GBC. Five fluorouracyl may be promising as adjuvant therapy associated with radiotherapy. Consideration should be given to a more aggressive screening with the up-to-date radiological tools, of high risk individuals and early resection of the gallbladder in high risk cases with any findings suggestive of gallbladder cancer. PMID- 9372379 TI - Short-term restorative nutrition in malnourished patients: pro's and con's of intravenous and enteral alimentation using compositionally matched nutrients. AB - In a prospective controlled clinical study 30 patients with moderate degree of malnutrition, normal liver and kidneys, and a functioning gastrointestinal tract were randomized to receive a free amino acid and small peptide enteral diet (15 patients) or an isonitrogenous isocaloric parenteral support for at least 10 days (total energy: 2900 kcal, nitrogen: 14.5 g, carbohydrates: 380 g, fat: 112 g, N/non protein calories: 1/175). The parenteral and enteral diets had the same protein/lipid/carbohydrate composition. The data indicated that both routes led to positive nitrogen balance. Nitrogen equilibrium was achieved by day 3 in the TPN group and by day 5 in the enteral group. There were no significant changes in serum albumin within either group. Serum level of transferrin reached a significant increase in both groups (p = 0.003). Thyroxine-binding prealbumin rose significantly in both groups as well (p = 0.019 and 0.004 respectively). Statistically significant rises in lymphocyte counts (p = 0.003 and 0.001 respectively), in levels of C3 (p = 0.009 and 0.001 respectively), IgA (p = 0.002), IgG (p = 0.004 and 0.003 respectively) and IgM (p = 0.004) occurred in either treatment group. There was a high incidence of negative skin tests at the start of the study in the enteral group (73.3%) and the TPN group (60%). By the end of the study the incidence of negative results for this test was 40.0% and 26.6% respectively. Despite maintenance of similar glucose levels in both groups, TPN led to significantly (p = 0.000) higher serum insulin levels. The serum insulin increased almost linearly over the study period, and eventually prevented fat mobilization and lipolysis, so that free fatty acid levels had fallen significantly (p = 0.000). A significant elevation of the liver enzymes over the study period occurred in the TPN group, but not in the enterally fed patients. The present findings provide no evidence that semi-elemental diets are in any way inferior to isonitrogenous isocaloric regimes parenterally given for a short period of time. PMID- 9372380 TI - Sigmoid perforation, an exceptional late complication of peritoneal prosthesis for treatment of inguinal hernia. AB - Two cases of sigmoid perforation and fistula occurred as late complications after insertion of a nonresorbable prosthesis by the open preperitoneal inguinal route. These infrequent complications are favoured by peritoneal defects and use of materials which can cause extensive sclerous reactions. Indications for this type of mesh are increasingly common with the intraperitoneal laparoscopic approach, so that careful peritoneal dissection and closure are required. PMID- 9372381 TI - Facilitation of tumor metastasis after hepatic resection in rats. AB - BACKGROUND: In an attempt to ascertain for possible facilitation of tumor metastasis after hepatectomy, a series of experiments was carried out using the RBT-1 carcinoma. METHODS: The animals were separated into three groups: Group A, received no treatments, Group B, received a sham operation, and Group C underwent partial hepatectomy. Three groups had viable tumor cell injected into the tail vein after the treatment. RESULTS: The mean survival periods in Group A, B, and C were 32.7, 28.8, and 24.8 days, respectively. When a comparison was made with all groups, survival time was significantly shorter in Group B and C than Group A (p < 0.01), and in Group C, compared with Group B (p < 0.05). Fourteen days after initial injection of RBT-1 tumor ten rats in each group were sacrificed and their lungs were assessed for evidence of metastatic spread of tumor. The mean number of metastatic nodules in Group A, B, and C were 5.1, 11.5, and 49.8, respectively. The number of metastatic nodules in the lungs was significantly increased in Group B (p < 0.05) and C (p < 0.01), compared to Group A, and in Group C, compared with Group B (p < 0.01). The facilitation of metastasis by surgical treatment was examined in relation to serum adrenocortical hormones. After the treatment, serum corticosterone levels were transiently increased in Group B (p < 0.01) and C (p < 0.01), compared to Group A, and in Group C (p < 0.01), compared with Group B. CONCLUSIONS: These results are taken to mean that facilitation of tumor metastasis after hepatectomy was possibly increased. PMID- 9372382 TI - Laparoscopic modified Sugiura procedure: experimental study on the pig. AB - BACKGROUND: The Sugiura procedure is an alternative treatment for bleeding gastroesophageal varices. Laparoscopic Sugiura procedure has not previously been described. The aim of this study is to develop a laparoscopic oesophageal transection with an EEA stapler, as well as a complete laparoscopic modified Sugiura procedure. METHODS: We used six female farm pigs weighing 40-50 kg. Six trocars were used. The steps of the procedure are: 1) mobilization of the lower oesophagus and truncal vagotomy; 2) oesophageal resection-anastomosis with an EEA stapler; 3) devascularization of the corpus and fundus of the stomach and the lower 10 cm of the oesophagus; 4) splenectomy; 5) Nissen fundoplication; 6) pyloroplasty. RESULTS: The mean operation time was 180 min, while the mean blood loss 260 ml. All staple lines are integral during autopsy at the end of the procedure. CONCLUSIONS: Laparoscopic oesophageal transection with an EEA stapler as well as a complete laparoscopic modified Sugiura procedure are feasible. PMID- 9372383 TI - Penetrating thoraco-abdominal war injuries. AB - BACKGROUND: From April 1991 till December 1995, Split University Hospital played a major role as a third echelon war hospital during the war in Croatia and Bosnia and Herzegovina. Among 2856 treated battle casualties in general, 70 patients with penetrating thoraco-abdominal war injuries were treated at the Department of Surgery. Explosive wounds were present in 38 (54%), gunshot wounds in 32 (45%) and puncture wounds in four (5.70%) patients. METHODS: The medical data from the evacuation unit, transportation, emergency department, surgical management and follow-up were obtained and analyzed. The principle of treatment of such patients is described, with particular reference to thoracophrenolaparotomy as the most efficient diagnostic-therapeutic surgical approach. RESULTS: There were considerably more explosive wounds than gunshot and puncture wounds (ratio 38/32/4). Resource utilization analysis showed a great amount of blood products (average 1.250 ml per patient), rehydrant solutions (average 3.750 ml per patient) and seven days antimicrobial chemoprophylaxis (penicillin, gentamycin, metronidazole) used. Mean time elapsed between injury and definitive surgical repair was seven hours (range, 1 to 48 hours). Recovery on discharge was recorded in 61 (80%) and lethal outcome in nine (13%) patients. CONCLUSIONS: The treatment of respiratory insufficiency and hemorrhagic shock, and prevention of infection are the basis of the management of these injuries. Treatment success depends on emergency first-aid, quick transportation, early diagnosis, resuscitation, surgical therapy and intensive care. PMID- 9372384 TI - Esophageal cancer in patients with head and neck cancers. AB - Nine male patients with separate primary cancers of the esophagus and head and neck (pharynx, larynx) presented with a mean age of 56 years (41-69). They included 7 pharyngeal cancer patients and 2 laryngeal ones. Esophageal cancer was discovered synchronously in 6 patients and metachronously in 3 (1, 4, and 11 years later, respectively). The head and neck cancer was stage-I in one patient, stage-II in 4 and stage-IV in 4. The esophageal cancer was cervical in 2, thoracic in 6 and abdominal in 1. It was early cancer (stage-0) in 6 patients and advanced (stage-IV) in 3. The esophageal cancer was more advanced in the metachronous group, while it was early in the synchronous group. Since the head and neck cancer was advanced, all patients underwent a total laryngectomy for their head and neck cancers. As for esophageal surgery, a transhiatal esophagectomy was, in principle, performed for early cancers while a total thoracic esophagectomy was done for advanced cancers. For the reconstruction of the esophagus, a gastric tube was used. Four patients are still alive with a mean survival time of 25 months, whereas five died of cancer recurrence of either type a mean of 19 months after surgery. As compared with the survival rates of the patients with esophageal cancer alone, the 5-year survival rate was 18.2% for patients with double cancers in this series and 27.9% for those with esophageal cancer alone. PMID- 9372386 TI - 25 years of nurse education in the University of Wales College of Medicine. PMID- 9372387 TI - Malnutrition in geriatric patients: a neglected problem? AB - The nutrient intake in geriatric long-stay patients and the mortality risk associated with low energy intake were studied in 61 patients, 43 women and 18 men, with a mean age of 87 years, at a geriatric long-stay care hospital during a 6-month follow-up. Dietary intake was assessed with a 9-day dietary record. Energy expenditure was calculated assuming a physical activity level of 1.33 x basal metabolic rate (BMR), predicted from equations given by FAO/WHO. Mean energy intakes were 1557 kcal in men and 1280 kcal in women; 84% of the patients had an intake below estimated energy expenditure and 30% were below estimated BMR. Only 5% received dietary supplement. Eleven out of the 61 patients died during the follow-up and the deceased had lower energy intake than the others (1185 kcal vs 1401 kcal, P < 0.05). An energy intake below median (1378 kcal) was associated with an age adjusted increased 6-month mortality risk, odds ratio 12.5. A high proportion of geriatric long-stay patients report dietary intake far below present recommendations and are thereby at risk for having/developing malnutrition. Improved surveillance of geriatric long-stay patients' dietary habits seems justified. PMID- 9372385 TI - Efficacy of ketorolac tromethamine and extrapleural intercostal nerve block on post-thoracotomy pain. PMID- 9372388 TI - Undernutrition in the elderly population living at home in the community: a review of the literature. AB - Undernourishment in elderly people has been found to have a variety of detrimental effects ranging from the development of pressure sores to the incidence of fractured femurs. Surveys within hospital settings have revealed that elderly patients are often admitted from their homes in a state of malnutrition, which would indicate nutritional deficits in at least some of the population. Reliable nutritional assessment in the community, however, is difficult and time consuming, with findings subject to distortions from other influences. Consequently there is inadequate accurate assessment of the current nutritional status of the general elderly population, and assumptions are often based on research findings from the 1960s and 1970s. In view of the demographic changes which have moved towards an increasingly 'old' elderly population such research may no longer be relevant. This paper provides a review of the available literature on nutrition in elderly people living at home and includes possible assessment screening strategies that could be used by community nurses. PMID- 9372389 TI - The transition to nursing home life: a comparison of planned and unplanned admissions. AB - The percentage of elderly people in nursing homes increases with age from 7% for adults aged 75-84 years to 20% for those over 85 years old. Limited research has been done with elderly people whose admission to a nursing home was planned or unplanned. This study addressed: what are the initial experiences of elderly people in making the transition to nursing home life when the admission was planned or unplanned? A grounded theory approach using constant comparative methods was used to discover the process and patterns of transition to nursing home life. Data were collected 24 hours after admission and every other day for 2 weeks, and 1 month post-admission using in-depth semistructured interviews and field notes. Data analysis demonstrated that the transition to nursing home life occurred in three phases: overwhelmed, adjustment and initial acceptance phase. The phases of adjustment are discussed along with interventions to assist older adults in making this transition. PMID- 9372390 TI - A cost-effectiveness analysis of home care and community-based nursing homes for stroke patients and their families. AB - A prospective study designed for 336 hospitalized patients with stroke and their families, who were followed from the discharge day to the third month after being discharged, was carried out in order to compare the costs and effectiveness of home care with the community-based nursing homes for stroke patients with different physical function disabilities in terms of ADL scores and their families. The ADL scores of the patients with severe physical function disability did not improve with or without long-term care; however, the patients with moderate physical function disability were significantly improved at the end of the third month, even without interventions from long-term care. The family costs of the patients in nursing homes were substantially lower than the costs for the patients who stayed at home, and the relationship of the family costs of the patients cared for in their own homes was proportional to the patients' physical function status. The labour input from family caregiving accounted for at least 60% of the total family costs of the patients who stayed at home, and the paid for long-term care services accounted for at least 60% of total family costs when the patients stayed in nursing homes. The multiple linear regression demonstrated that the degree of caregiving from families was a predictor of the amount of the costs families incurred for patients with severe physical function disability; as a result the ADL scored on discharge significantly influenced the average total family costs for the patients cared for in their own homes. PMID- 9372391 TI - Emotional problems in primary care: what is the potential for increasing the role of nurses? AB - It has been suggested that the role of primary care and community nurses should be expanded in relation to mental health in order to assist in the prevention and management of prevalent emotional disorders such as depression and anxiety. However, relatively little is known about the mental health work presently undertaken by these nurses. Furthermore, nurses' training needs, attitudes and organizational barriers to role expansion in this area have not been systematically explored. This article seeks to review the literature on nurses' potential and current mental health work, current and future training needs, the views of patients and nurses concerning an expanded nursing role, and organizational issues of relevance. Educational interventions which have been systematically evaluated are also reviewed. The results suggest that nurses are already involved in emotional health care with a variety of patient groups, although this is not always acknowledged as mental health work. While clear potential for an expanded role exists, there is little consensus as to what role would be most effective for each nursing group, and few educational interventions have been demonstrated to be of proven effectiveness. PMID- 9372392 TI - Stigma. AB - This study started as a literature review on stigma as part of a Professional Studies II Resettlement Course. While conducting the study the author was able to follow-up previous research which looked at contact with the mentally ill and stigma. The authors Trust opened a new community mental health base and the study looked at local residents' attitudes towards the mentally ill both 6 months prior to the opening and again 6 months after. A control area 5 miles from the base was also surveyed on both occasions. The study found that the opening of the base had little or no effect on the attitudes of local residents. However, there was evidence that attitudes towards the mentally ill had hardened both locally and within the control area. PMID- 9372393 TI - The psychological characteristics of patients suffering from anorexia nervosa and the nurse's role in creating a therapeutic relationship. AB - This paper reviews research on the psychological characteristics of patients suffering from anorexia nervosa and that examining the therapeutic relationship. The former research suggests that anorexic patients possess a psychological profile characterized by: a phobia of weight gain and fear of loss of control; alexithymia and lack of introceptive awareness; mistrust of self and others; cognitive dysfunction; low self-esteem; and often the presence of starvation induced depression. The latter strongly suggests that in order for a relationship to be therapeutic it needs to be characterized by: empathy; positive regard and acceptance; warmth; commitment; trust; genuineness; and be non-judgemental. The implications of these research findings regarding the nurse's role in forming a therapeutic relationship with anorexic patients is then discussed. It is seen that it is vital that nurses receive adequate education before working with such patients, and that their knowledge is regularly updated. Nurses should receive regular clinical supervision and support, in order to ensure that they are able to provide therapeutic care for such patients. PMID- 9372394 TI - Elements of psychological support in nursing care. AB - The paper presents the results of a pilot study which involved 50 nurses from several departments of internal medicine of The State Clinical Hospital of the Collegium Medicum, Jagiellonian University in Cracow. The results are based on the Statement Response Questionnaire. They show that the most common responses of the nurses in the face of anxiety expressed by patients are cheering up the patient, collecting information about the symptom, and offering explanation of the symptom. The least common responses included expressing one's own positive emotions and showing empathy towards the patient. PMID- 9372395 TI - A group programme for postnatally distressed women and their partners. AB - A group programme for postnatally distressed women and their partners is described. The programme consists of eight sessions, including one session for the couple. The concerns of the women centre around their anxieties and feelings towards their partners, their own mothers and their infants. Psychotherapeutic and cognitive-behavioural strategies are employed to assist them in dealing with these concerns. The concerns of the men centre around their attempts to provide emotional and practical support to their partner. Invariably such support results in an increase in tension between the partners, and the programme helps the men to understand why this happens. Formal measures show a decrease in maternal distress over time and an increase in their level of self-esteem. About half of the men show elevated levels of distress. PMID- 9372396 TI - Depression in female health visitor consulters: social and demographic facets. AB - The primary health care setting has been established as a key venue for identifying and working with depression. Despite this, and the high risk of depression experienced by women in the postnatal period, maternal depression has been little examined in the work of health visitors. Furthermore, although research has been undertaken on social factors related to depression in the general population, there is nothing specifically on the population of health visitor clients. This study focuses on social and demographic factors related to maternal depression amongst users of health visitor services. In a study of 701 women in rural and urban areas, maternal depression was found to be significantly associated with the absence of receipt of further or higher education, housing status, employment status, reliance on state benefit, family size, family breakdown (reconstituted families and single divorced or separated women), perceptions of support and difficulty in getting children off to sleep, particularly after the first year of the child's life. Loglinear analysis was used to identify the most parsimonious model of these relationships, and three key areas emerged: social and economic disadvantage, family size and history of family disruption. The model suggested that 'behind' these data may have been poor life chances, as evidenced by data on further and higher education. These data identify elements of objective life circumstances important for depression in this group. They have considerable significance for the organization of health service resources and these are discussed. PMID- 9372397 TI - Community psychiatric nurse caseloads and the 'worried well': misspent time vital work? AB - Community psychiatric nurses (CPNs) in the United Kingdom are being repeatedly urged to focus their attention upon those with serious and enduring psychotic illnesses, and to withdraw from working with the 'worried well' in the primary health care setting. In view of this pressure, it is important to discover the nature of community psychiatric nurses' non-psychotic caseloads. The aim of this study was to describe these cases, what precipitated their referral, what problems they suffered from, what effects these problems had upon their lives and what kinds of therapeutic interventions they were receiving. A random sample was drawn of non-psychotic CPN patients. The community psychiatric nurses then received a structured interview about the history, care and treatment of these patients. These patients did not, in general, suffer from minor, self-limiting conditions. They typically had had 5 years of contact with psychiatric services, and their psychiatric symptoms blighted their occupational, social and personal lives. Their condition caused significant carer burden, and there was frequently a risk of suicide. The CPNs case-managed a complex combination of interventions for these patients, of which psychotherapeutic methods were only one part. The findings show that community psychiatric nurses have a valid role to play in the care of those with non-psychotic mental disorders, and should continue to receive the opportunity, and appropriate training, to do so. PMID- 9372398 TI - Evaluating the impact of in-patient bed reduction and community nurse increases in one English Mental Healthcare Trust. AB - This Mental Health Task Force funded project was designed to evaluate the impact of organizational changes in Northampton, a traditional English Mental Healthcare Trust. Services in Northampton were typically provided by a large 'watertower' Victorian hospital on the outskirts of the town. The hospital had been, over a period of some years, reducing the use of in-patient beds. In February 1995 a further 10 beds were withdrawn enabling the closure of a complete building and the re-deployment of some staff into the community. By reducing in-patient beds, and increasing the number of community staff it was hoped that there would be a significant effect upon both hospital admissions, length of stay with resultant cost savings, and an increase in community nurse-patient contacts. To establish baselines quantitative data were gathered about pre-existing acute and community services, with comparisons made from qualitative and quantitative data gathered during the initial change period. Information was collected concerning in-patient admissions within the acute services, community psychiatric nurse (CPN) caseloads including new admissions, care delivery costs and interviews with service managers. The project found that changes in the general patient profile could not be attributed solely to the reduction in available beds but there did appear to be a direct correlation between bed reduction, increase in percentage bed occupancy and more demanding CPN caseloads. Concern was expressed about the ability of community staff to meet the needs of an increasingly female (age 20-39 years) user group. Savings to the Trust were estimated at Pounds 300,000 per annum. The paper concludes with recommendations for future changes. PMID- 9372399 TI - Decision-making and paediatric pain: a review. AB - The aim of this paper is to present an overview of the literature on the factors influencing decision-making in the nursing care of children in pain. To that effect published and unpublished references were reviewed. The most frequently cited factors influencing the assessment and management of pain in children are summarized and discussed. Finally recommendations are made where further research is warranted. PMID- 9372400 TI - Critical care nurses, ethical decision-making and stress. AB - Considerable attention has focused on describing ethical issues that critical care nurses face in their practice: however, less attention has been directed at describing the process of ethical decision-making. Systematic research linking aspects of ethical-decision making and stress is lacking. This cross-sectional study examines the relationship between selected aspects of ethical decision making, stress and selected nurse characteristics. Sixty-one critical care nurses completed the Nurse's Ethical Decision Making--ICU Questionnaire and the Health Professions Stress Inventory. Findings revealed that nurses who selected the patient advocacy model had significantly higher nurse autonomy scores, that perceived anxiety had a negative association with nurse autonomy, and that workplace restrictions and stress were related. PMID- 9372401 TI - Tension neck and evaluation of a physical training course among office workers in a bank corporation. AB - The purpose of this study was to investigate the effects of a physical training course in a group of patients (n = 74) suffering from chronic tension neck. All participants in the course were employed by a bank corporation in Helsinki, Finland. A comparable control group (n = 77) consisted of office workers with tension neck from the same bank corporation who did not attend any training course. The outcome was analysed 6 months after the course. Pain and disability in the neck and shoulder region did not vary significantly between the group which participated in the training course and the control group. The experimental group had increased the amount of physical workout compared to the control group (83.7% vs 69.0%, P = 0.0448). Also, regarding the frequency of relaxation and stretching exercises the two groups differed significantly: the experimental group had continued to perform exercises more often (P = 0.0434). The frequency of sick leave days did not significantly differ between the groups, but the office workers in the experimental group had more periods of extended sick leave (> 10 days) and the controls had more frequent short sick leaves. The experimental group did increase their physical workout significantly compared with the controls, but no differences were detected regarding pain and disability. In order to gain more benefit more attention should be paid to the educational part of the training courses in order to enhance the patients' self care abilities. Also, strategies to alleviate psychosocial problems and organized relaxation exercises could decrease muscle tension in the neck in office workers. PMID- 9372403 TI - Cancer and beyond: the question of survivorship. AB - Today, more people are surviving cancer as a result of improved treatment and early diagnosis. In Australia, the 5-year survival rate for persons diagnosed with cancer is now approaching 50%. Although there is a growing population of cancer survivors, little is known about what surviving entails. Traditionally, a survivor has been defined as one who has been disease-free for more than 5 years. However, this definition does not take into account the experience nor the process of survival and the aim of this article is to document the process of surviving cancer as reflected in the experiences of cancer survivors. Using a method of hermeneutic phenomenology (as described by van Manen), the study draws on the stories of six women, who by their definition, are surviving cancer. A discussion of themes has been structured according to the everyday experiences of living in a body and living in time. The women describe a survival process that includes: 'feeling whole again'; 'the body as the house of suspicion'; 'the future in question'; 'changes in time'; 'lucky to be alive'; and 'sharing the journey'. PMID- 9372402 TI - Non-adherence with medications in organ transplant patients: a literature review. AB - The problems of non-adherence with treatment in health care in general, and with medication adherence in particular, is an area with a voluminous and burgeoning literature. However, there appears to be no review of the literature on non adherence with medications in organ transplant patients. This comprehensive review therefore considers literature on adherence in adult kidney, heart and liver transplantation. The particular problem of adherence in paediatric transplant patients is also addressed. This transplant research literature is then evaluated within the broader context of social science research on medication adherence. From the review it is apparent that there is an urgent need for research which examines the patient's beliefs about their illness and medicines. Such research is a precursor for rigorous nursing intervention studies which aim to promote adherence by being tailored to the patient's perceptions. PMID- 9372404 TI - A descriptive study of the readability of patient information leaflets designed by nurses. AB - Written patient information materials can be valuable communication tools for teaching and reinforcing the verbal message, especially in the present climate of today's health service where patients are in hospital for such short times. They are only useful if the patient is able to read and understand them, otherwise they become an expensive waste of resources. Various studies have shown that many healthcare information leaflets are written at university or postgraduate level and would cause problems with understanding for many people reading them. This study set out to examine the readability of nurse-designed written information leaflets using the Flesch Reading Ease score and the FOG and SMOG readability formulae. This descriptive study used a sample of 24 leaflets designed by trained nurses in a large teaching hospital. The results produced a mean grade of 11.3 with a range of 8.9 to 14.8. This was similar to the results of other studies and meant that patients may have difficulty comprehending the information. It would appear that little progress has been made in 40 years in this area and potential reasons are discussed. Advantages and disadvantages of readability formulae and other guidelines available for developing information leaflets are explored. Recommendations for further research are made. PMID- 9372405 TI - Caring for parents of hospitalized children: a hidden area of nursing work. AB - Children are the recognized patients when admitted to hospital but their parents can also present demands for care by nurses. Involvement in care can be stressful for parents, particularly when children are required to undergo unpleasant procedures. Parents turn to their families for support in the first instance but some also look for care from nurses. Consequently parents can present a need for care of themselves to nurses whose primary patients are children. In this paper the experiences of a group of parents who became co-clients of nurses are considered along with the views of nurses working on the same ward. The discussion arises out of a larger study of the experiences of the parents of children admitted to a surgical ward in a children's hospital. The principal purpose of the study was to examine parents' and nurses' perceptions of their participation in the care of hospitalized children. The work of caring for parents is found to be ad hoc and unpredictable. The implications of the study for practice and policy are considered. PMID- 9372406 TI - Professional caring: a contradiction in terms? AB - The caring activities which are traditionally associated with the nursing and midwifery professions comprise two essential and inseparable elements: the instrumental and expressive. Yet the former appears to be attracting an emphasis which threatens the integrity of the whole. In this paper, the reduction in altruistic values in society is identified as one possible cause, and examples of practice which fall short of the ideal are identified. Also, the ways in which current educational, professional and organizational goals appear detrimental to expressive caring, while endorsing the instrumental component, are discussed. It is argued that in order for caring, in its traditional sense, to be perpetuated in practice, there is need for increased educational focus, the ability of practitioners to identify the implications of current changes in the United Kingdom for practice and the commitment to maintain caring as a central value. PMID- 9372407 TI - Critical thinking skills: the role of prior experience. AB - The critical thinking skills students bring with them on entering university courses will necessarily have a bearing on how they manage their studies and gain new knowledge. This study examined postgraduate nursing students' perceptions of their gains in critical thinking abilities through engagement in off-campus studies after three semesters of study. Data for the study were collected by survey methodology. Descriptive statistics were derived and correlation analyses performed using SPSSx. This study indicates that for most skills, the differences between those students with prior university experience and those without it in perceptions of change in skill ability were not marked. For most critical thinking skills, about one half or a little more of the students perceived an overall positive shift in their abilities. For some skills, however, there were marked differences in the proportion of students perceiving a shift in skill ability, and possible explanations are offered. The results also indicate that a considerable proportion of the students surveyed perceived a lack of critical thinking skill development. As a result questions can be raised about how off campus students without prior university experience engage with tertiary studies. The implications of these findings in terms of the development of off-campus nursing course materials and student learning are discussed. PMID- 9372409 TI - A nursing journey through discursive praxis. AB - This paper argues that conceiving nursing as a form of praxis, encompasses amongst other things, the critical reflection upon one's nursing practice in order to work out and understand internal and external constructions of personal theories. This reflective examination will demonstrate the implicit knowing that nurses develop as a result of their personal, day to day practice. Highlighting this knowing and incorporating the richness of their practice experience becomes the basis for their own personal nursing praxis. PMID- 9372408 TI - Using a phenomenological research technique to examine student nurses' understandings of experiential teaching and learning: a critical review of methodological issues. AB - This paper provides a report of the usage of a phenomenological research methodology to investigate the influence on clinical practice of pre- and post registration nurse education which makes explicit use of experiential teaching and learning approaches. The primary aim of the research was to explore the use of a phenomenological research methodology to examine the students' understanding of experiential teaching and learning. The claims made for the use of experiential teaching and learning approaches in both pre- and post-registration nurse courses and how clinical practice is influenced by the experiential learning elements of pre- and post-registration nurse education were also examined. The first stage of the enquiry involved focused non-directive interviews with members of BSc Nursing Studies and MSc Mental Health Branch programmes. Both programmes claim to make use of experiential teaching and learning. The data were analysed using a technique developed by Giorgi. Previous experiences of experiential teaching and learning were probed, student interpretations differentiated, and the relationship between course-based learning using experiential approaches and the implications for it's influence on practice were examined. The second stage of the enquiry has followed up the initial findings, exploring the students' experience of experiential approaches on their courses both in the classroom and in work-based learning situations. The findings are presented and discussed in the context of other studies from both nurse and higher education. Throughout the paper methodological concerns arising are discussed. The paper concludes with the identification of methodological problems arising from the research strategy: the implications of the power nexus created when teachers research students, and issues relating to the use of a phenomenological methodology in a longitudinal study. PMID- 9372410 TI - A 'bonding between strangers': a palliative model of clinical supervision. AB - This paper examines the role of clinical supervision in relation to the work of palliative care nurses. Through a single 'paradigm' case study illustration the author explores a phenomenologically guided palliative method of supervision. It is suggested that such means of supervised clinical practice forge a bond between patients, families, nurse and colleagues. The discussion explores ethical issues related to supervisory relationships including language, power and gender. The paper concludes with the central recommendation that, aside from methodological considerations, constructing a safe working environment for clinical supervision is important. PMID- 9372411 TI - The implications of Project 2000 and the formation of links with higher education for the professional and academic needs of nurse teachers in the United Kingdom. AB - A national study was conducted between 1991 and 1994 to explore and describe the changing role of the nurse teacher following the introduction of Project 2000 pre registration nursing courses. Multiple methods were used to collect data from a wide variety of respondents (nurse teachers, midwife teachers, clinical nurses, health service managers and higher education lecturers). This paper presents the findings relating to the impact of Project 2000 and the move into higher education on the continuing educational needs of nurse teachers. Views on college strategies for staff development, the changing nature of teachers' academic and professional development needs and the problems of the conflicting demands experienced are reported. The research highlights the need for clinical credibility to be clearly defined in relation to nurse teachers and for educational institutions to place more emphasis on teachers' clinical development if the rhetoric of policy is to become a reality. PMID- 9372412 TI - The relationship between research and the nursing process in clinical practice. AB - The nursing process was originally adopted by the North American nursing profession from the general systems theory (GST) and quickly became a symbol of contemporary nursing as well as a professionalist nurse ideology. In contrast its initial introduction in the United Kingdom (UK) was not a complete success. This could be attributed to the mode of its implementation, which utilized a power coercive change strategy, that is, comprising of imposition from above without sufficient time for education regarding its scientific and philosophical foundations. Consequently the nursing process was initially regarded as a professional and educational mandate rather than an organizational component of nursing care delivery. It has been maintained that the theoretical basis from which the nursing process was derived, together with the theoretical developments in diagnostic and intervention studies, has established the nursing process as a key element of the nurse's role in research, education and practice. This paper will briefly review the early theoretical developments and fate of the nursing process as a tool for clinical practice and research. It will then examine recent attempts to revitalize and modernize the theory for practice through research into nursing diagnosis. PMID- 9372413 TI - Empirical antimicrobial therapy of mechanically ventilated patients with nosocomial pneumonia. PMID- 9372414 TI - Antimicrobial treatment of pulmonary colonization and infection by pseudomonas aeruginosa in cystic fibrosis patients. PMID- 9372416 TI - Zinc ion availability--the determinant of efficacy in zinc lozenge treatment of common colds. AB - This is a re-analysis of reports from 1984 to 1992 of double-blind, placebo controlled, clinical trials of zinc lozenges in the treatment of common colds. This re-analysis was performed to test the hypothesis that major variations in daily zinc ion availability (ZIA) between chemically different lozenge formulations caused differing results in these clinical trials. Solution chemistry computations determined the bioavailability of Zn2+ ions at physiological pH from the lozenges used in these clinical trails. ZIA was derived from Fick's laws of diffusion in a bio-electric field. Lozenges that released Zn2+ ions at physiological pH (positive ZIAs) shortened colds. Lozenges that released negatively charged zinc species at physiological pH (negative ZIAs) lengthened colds. Lozenges having a zero ZIA had no effect on common colds. Lozenges with ZIA = 100 shortened colds by 7 days while ZIA = -55 lozenges lengthened colds by 4.4 days. A linear dose-response relationship exists between ZIAs of zinc lozenges and changes in duration of common colds. It is concluded that: prospective efficacy of zinc lozenges can be predicted based upon readily determined ZIA factors and ZIAs; chemically different zinc lozenge formulations having greatly different ZIAs resulted in greatly differing results in clinical trials; mast cell granule-derived Zn2+ ions are the foundation of the primary immune system; and high ZIA zinc acetate lozenges are beneficial for common colds. PMID- 9372415 TI - Cross-protection by anti-core glycolipid antibodies: evidence from animal experiments. AB - The ability of antibodies against the core glycolipid (CGL) of endotoxin to protect experimentally infected animals against death from Gram-negative sepsis is reviewed. The limitations and confounding factors inherent to animal models of sepsis are also briefly discussed. This review considers 30 studies in mice and 12 in other animal species that investigated protection against heterologous challenge by passive immunization with anti-CGL antibodies. In 28 (67%) of the reviewed studies antibodies were found to be protective, either prophylactically (n = 17) or therapeutically (n = 11). With the possible exception of the type of antibody preparation that was used (monoclonal versus polyclonal antibodies), none of the many differences in the experimental protocols were clearly correlated with success. Convincing proof is still lacking for any of the hypothetical mechanisms of protection by anti-CGL antibodies. Moreover, the evidence that protection by these antibodies is attributable to their anti-CGL specificity is poor. The available data raise serious questions about the validity of the concept underlying the search for broadly cross-protective antibodies raised against the core region of endotoxin. However, continuing research suggests that endotoxin still is a valid target in devising new adjunctive treatment strategies to improve the outcome of serious Gram-negative infections. PMID- 9372417 TI - The response of Enterobacteriaceae to beta-lactam antibiotics--'round forms, filaments and the root of all evil'. PMID- 9372418 TI - Antibiotic effects in vitro and the prediction of clinical response. PMID- 9372419 TI - Bay 12-8039, a new 8-methoxy-quinolone: comparative in-vitro activity with nine other antimicrobials against anaerobic bacteria. AB - The in-vitro activity of a new 8-methoxy-quinolone, Bay 12-8039, was assessed against 218 anaerobic bacteria. Ninety-eight per cent of strains belonging to the Bacteroides fragilis group (n = 65) were inhibited by < or = 2 mg/L of Bay 12 8039 whereas 97%, 94%, 94% and 100%, respectively, of Gram-negative bacilli (n = 93), non-sporing Gram-positive bacilli (n = 36), endospore-forming Gram-positive bacilli (n = 34) and Gram-positive cocci (n = 45) were also inhibited by < or = 2 mg/L. Eighty-three per cent of all anaerobes tested were inhibited by < or = 1 mg/L Bay 12-8039 and 99.5% by < or = 4 mg/L. When compared with ciprofloxacin, clinafloxacin, ofloxacin and trovafloxacin, Bay 12-8039 was more active than ciprofloxacin and ofloxacin, equipotent to trovafloxacin but not as active as clinafloxacin. PMID- 9372420 TI - Fluconazole disc diffusion testing for the routine laboratory. AB - The increasing incidence of resistance to the antifungal agent, fluconazole, prompted the need for a rapid, reliable and easy-to-use susceptibility test. We have developed a disc diffusion test for fluconazole against Candida spp. suitable for a clinical laboratory. Disc diffusion tests on six different media were compared with MIC values. On the basis of correlation coefficient with MICs (r = -0.95), quality of growth and zone edge definition, Yeast Nitrogen Base agar with glucose (YNBG) produced the best results. Further studies on YNBG showed that the method is reliable for Candida albicans and for resistant isolates with no zone of inhibition, but results for the slower growing and uncommon species must be interpreted with some caution. Implementation of this test in the clinical laboratory has provided a much needed therapeutic service for clinicians within the hospital. It has also reduced the reliance on the reference laboratory for susceptibility results and the consequent costs involved. PMID- 9372421 TI - Unresponsive HIV-related oro-oesophageal candidosis--an evaluation of two new in vitro azole susceptibility tests. AB - Azole-resistant HIV-related candidosis is increasingly recognized. We evaluated two new in-vitro susceptibility tests (the NCCLS proposed MIC method and Odds' assessment of relative growth in single anti-fungal concentration) as predictors of the clinical outcome of 66 HIV-positive patients with oral candidosis, of whom 22 were azole naive, 27 had always previously responded to azole therapy and 17 had persistent candidosis unresponsive to 7 days of standard azole therapy. None of the last group responded to increased daily doses of fluconazole or itraconazole capsules, though nine responded to itraconazole cyclodextrin solution 200 mg bd for 7 days. Our findings suggest that agreement between the Odds' test and the MIC method was excellent (96-98%) and that both could discriminate between isolates of azole-unresponsive patients and those of azole responsive patients. For fluconazole susceptibility an MIC > or = 8 mg/L detected fluconazole-unresponsive patients with a sensitivity of 94% and specificity of 100%; Odds' method achieved 100% sensitivity and 100% specificity using all cut offs between 77 and 88% relative growth in medium containing fluconazole (10(-5) M; 3 mg/L). For itraconazole and ketoconazole agreement between MIC and Odds' method was again excellent (98% and 96%, respectively) but five azole unresponsive patients appeared to have ketoconazole-susceptible organisms as defined by both tests, and similarly 11 appeared to have itraconazole-susceptible organisms by both tests despite failing to respond to the capsule formulation of the drug. Of these 11, eight responded to itraconazole solution; this finding implies that itraconazole capsule failure might represent poor drug absorption rather than fungal resistance. PMID- 9372422 TI - Mechanism and stability of hyperproduction of the extended-spectrum beta lactamase SHV-5 in Klebsiella pneumoniae. AB - Some isolates of SHV-5 beta-lactamase-producing Klebsiella pneumoniae K2 from a single-strain outbreak of cross-infection produced approximately five-fold more beta-lactamase than others. We investigated three possible genetic mechanisms of this hyperproduction: the presence of a more powerful promoter, an increase in plasmid copy number or an amplification of the gene on a plasmid. No differences between low and high beta-lactamase producers were detected in the promoter region of the SHV-5 beta-lactamase gene, which closely resembled that of SHV-2. SHV-5 beta-lactamase production was encoded on a low copy number plasmid, but DNA DNA hybridization with an SHV-specific probe detected a higher gene dose in hyperproducers. The beta-lactamase hyperproduction was unstable on repeated subculture, with a reduction of about 75% after 100 generations. Hyperproducing mutants of a low-producing Klebsiella and its Escherichia coli K-12 transconjugants could be selected in vitro at a frequency of 10(-5) to 10(-6) and these variants had an increased SHV-5 beta-lactamase gene copy number on low copy number plasmids. We conclude that hyperproduction of the extended-spectrum beta lactamase was caused by gene amplification that could be easily lost or gained in vitro. Since the change to hyperproduction occurred at a high frequency and hyperproducers showed increased resistance to many beta-lactams and beta lactam/beta-lactamase inhibitor combinations, we suspect that these variants may readily be selected in patients during antibiotic therapy. PMID- 9372423 TI - Bases of variation in resistance to beta-lactams in Klebsiella oxytoca isolates hyperproducing K1 beta-lactamase. AB - Nineteen isolates of Klebsiella oxytoca were examined, representing 18 distinct strains. All were from a 1994 survey of resistance amongst klebsiellae in intensive care units in Europe, and all had reduced susceptibility, or were resistant, to cefuroxime, ceftriaxone and aztreonam, suggesting hyperproduction of the chromosomal K1 beta-lactamase. We sought to confirm this mechanism and to identify why the levels of resistance varied between isolates. Possible reasons for variation were differences in the quantity or subtype of the K1 enzyme or differences in this enzyme's interplay with permeability. Spectrophotometric assays showed that all 19 isolates had K1-like beta-lactamases and that these were present at > or = 15-fold higher levels than in beta-lactam-sensitive K. oxytoca isolates. Fourteen of the 19 isolates had the OXY-2 form of K1 enzyme, while the remaining five had the OXY-1 form, as determined by isoelectric focusing and PCR amplification. Most isolates with the OXY-2 enzyme were more resistant than those with the OXY-1 subtype, but this difference partly reflected enzyme quantity rather than subtype. More generally, and irrespective of enzyme subtype, levels of resistance were broadly related to beta-lactamase specific activity, and the degree of hyperproduction was a major determinant of the level of resistance. Nevertheless, other factors had a role too: several isolates had reduced susceptibility or were resistant to cefoxitin, which is not a substrate for K1 enzyme, and examination of outer membrane protein profiles revealed considerable strain-to-strain diversity in the molecular weight range typical of the major enterobacterial porins (40-48 kDa). PMID- 9372424 TI - Detection of mutations in the gyrA and parC genes in quinolone-resistant clinical isolates of Enterobacter cloacae. AB - We have determined partial sequences of the gyrA and parC genes of Enterobacter cloacae type strain including the regions analogous to the quinolone resistance determining region of the Escherichia coli gyrA gene. The deduced 65- and 49 amino acid sequences of the determined regions of the E. cloacae gyrA and parC genes were identical to the corresponding regions of the E. coli GyrA and ParC proteins, respectively. We examined 40 clinical strains of E. cloacae isolated from patients with urinary tract infection for susceptibilities to nalidixic acid and ciprofloxacin. Based on the nalidixic acid and ciprofloxacin MICs, these isolates were divided into 19 quinolone-susceptible strains (MICs of nalidixic acid, 3.13-25 mg/L; MICs of ciprofloxacin, < or = 0.025 mg/L) and 21 quinolone resistant strains (MICs of nalidixic acid, 400 to > 800 mg/L; MICs of ciprofloxacin, 0.39-100 mg/L). We analysed five quinolone-susceptible and 21 quinolone-resistant strains for alterations in GyrA and ParC. The five quinolone susceptible strains had amino acid sequences in GyrA and ParC identical to those of type strain. Of the 21 quinolone-resistant isolates, three (MICs of nalidixic acid, 400 to > 800 mg/L; MICs of ciprofloxacin, 0.39-3.13 mg/L) had a single amino acid change at the position equivalent to Ser-83 in the E. coli GyrA protein and no alterations in ParC; one (MIC of nalidixic acid, > 800 mg/L; MIC of ciprofloxacin, 3.13 mg/L) had a single amino acid change at Ser-83 in GyrA and a single amino acid change at the position equivalent to Glu-84 in the E. coli ParC protein; two (MIC of nalidixic acid, > 800 mg/L; MIC of ciprofloxacin, 25 mg/L) had double amino acid changes at Ser-83 and Asp-87 in GyrA and no alterations in ParC; and 15 (MICs of nalidixic acid, > 800 mg/L; MICs of ciprofloxacin, 25-100 mg/L) had double amino acid changes at Ser-83 and Asp-87 in GyrA and a single amino acid change at Ser-80 or Glu-84 in ParC. This study suggests, that in clinical isolates of E. cloacae, DNA gyrase is a primary target of quinolones, that only a single amino acid change at Ser-83 in GyrA is sufficient to generate high-level resistance to nalidixic acid and to decrease susceptibility to ciprofloxacin, and that the accumulation of amino acid changes in GyrA and the simultaneous presence of the ParC alterations play a central role in developing high-level resistance to ciprofloxacin. PMID- 9372425 TI - Distribution and mobility of the tetracycline resistance determinant tetQ. AB - We tested 34 American Type Culture Collection (ATCC) and 168 clinical bacterial isolates, from the human urogenital and oral tracts and streptococci isolated from cows with mastitis, for the presence of the tetQ gene using a polymerase chain reaction (PCR) assay and DNA-DNA hybridization. The identities of PCR products were confirmed by Southern blot hybridization of whole-cell DNA. Eleven of the ATCC strains were positive for tetQ, including five Bacteroides spp., five Prevotella spp. and a single isolate of Mitsuokella multiacidus. Twenty-eight (29%) of the 95 clinical Gram-negative isolates carried the tetQ gene, while eight (11%) of the 73 clinical Gram-positive isolates carried the tetQ gene. This is the first description of tetQ in Gram-positive species. All isolates except one Peptostreptococcus sp. carried tetQ integrated into the chromosome. The tetQ gene could be transferred from Prevotella bivia, Bacteroides ovatus, Bacteroides fragilis, Bacteroides vulgatus and Bacteroides distasonis into an Enterococcus faecalis recipient at frequencies of 10(-7)-10(-9) per recipient. In contrast, tetQ failed to transfer from two isolates of Prevotella intermedia, two isolates of Porphyromonas gingivalis, one isolate of Mobiluncus curtisii and one isolate of Peptostreptococcus sp. The latter two are Gram-positive species. The PCR assay was used to screen 198 proteinase K-treated biopsies of prostate, periprostate and bladder from 84 men with prostatitis. Thirty-four (40%) of the patients had one or more positive samples, suggesting that the PCR assay could be of value in screening patient material directly for the presence of bacteria. PMID- 9372426 TI - Molecular evolution of the tet(M) gene in Gardnerella vaginalis. AB - Five clinical isolates of Gardnerella vaginalis known to carry the tetracycline resistance determinant Tet M were examined by hybridization and nucleotide sequencing. Four of the strains carried tet(M) genes with identical sequences. The two versions of the tet(M) gene found in G. vaginalis did not show complete identity with other published tet(M) sequences, but showed mosaic structures with regions of homology to tet(M) gene sequences from Tn916, Tn1545 and the American type plasmid found in Neisseria gonorrhoeae. Hybridization studies showed that all isolates carried the tet(M) gene on a single HindII restriction fragment of variable length. No evidence was found for the presence of sequences homologous to the transposition functions of Tn916. PMID- 9372427 TI - Evaluation of protection by two endotoxin-neutralizing IgM monoclonal antibodies in different peritonitis models. AB - Two anti-core glycolipid (CGL) IgM monoclonal antibodies (mAbs 8-2 and 26-20), previously shown to display cross-reactivity with heterologous lipopolysaccharide (LPS) in vitro and to provide cross-protectivity against endotoxin challenge in vivo, were evaluated for their potential to protect mice against death from peritonitis caused by heterologous bacterial challenge. Without concurrent antibiotic treatment neither antibody was protective. Compared with a control mAb, prophylactic treatment with mAb 8-2 significantly increased the survival of gentamicin-treated mice challenged with the rough strain Salmonella minnesota Re595. Both mAb 8-2 and a control mAb, in combination with a suboptimal dose of ceftazidime, increased survival following challenge with the clinical isolate Escherichia coli O7:K1. In a model of mucin-enhanced peritonitis, neither mAb was protective against challenge with inocula of E. coli O7:K1, ranging from 10(2) to 10(4) bacteria. We conclude that protection of mice by anti-CGL mAb 8-2 against heterologous challenge is vitally dependent on concurrent treatment with antibiotics and that protection may not be attributable to the anti-CGL specificity of these antibodies. PMID- 9372428 TI - Concentrations of levofloxacin (HR 355) in the respiratory tract following a single oral dose in patients undergoing fibre-optic bronchoscopy. AB - Concentrations of levofloxacin were measured in bronchial biopsies, alveolar macrophages (AM), epithelial lining fluid (ELF) and serum following a single oral dose. Concentrations were measured by a microbiological assay method. A total of 35 patients undergoing fibre-optic bronchoscopy were studied. Mean serum, AM, ELF and biopsy concentrations were as follows. 0.5 h: 4.73 mg/L, 19.1 mg/L, 4.74 mg/L and 4.3 mg/kg; 1 h: 6.6 mg/L, 32.5 mg/L, 10.8 mg/L and 8.3 mg/kg; 2 h: 4.9 mg/L, 41.9 mg/L, 9.0 mg/L and 6.5 mg/kg; 4 h: 4.1 mg/L, 27.7 mg/L, 10.9 mg/L and 6.0 mg/kg; and 6-8 h: 4.0 mg/L, 38.4 mg/L, 9.6 mg/L and 4.0 mg/kg respectively. Mean serum and AM concentrations at 12-24 h were 1.2 and 13.9 mg/L respectively (concentrations in biopsy and ELF were only measurable in three of the six patients). These concentrations exceed the MIC90s of the common respiratory pathogens, Haemophilus influenzae (0.015 mg/L), Moraxella catarrhalis (0.06 mg/L) and Streptococcus pneumoniae (1 mg/L) and suggest that levofloxacin should be efficacious in the treatment of community- and hospital-acquired respiratory infection. PMID- 9372429 TI - Failure of Neisseria gonorrhoeae to grow in the ATB NH susceptibility test system. AB - The ATB NH system designed for antibiotic susceptibility testing of Neisseria gonorrhoeae, Neisseria meningitidis and Haemophilus influenzae was evaluated using 94 clinical isolates of gonococci representing a wide variety of serovar/auxotype strains. Using the manufacturer's automated system 55% of the clinical isolates failed to grow, compared with a 33% failure rate for manual processing and visual reading. Growth failure was significantly higher with 1A isolates (73% automated and 69% manual) than with 1B isolates (49% automated and 25% manual). The higher failure rate of 1A isolates correlated with multiple auxotrophy. The inability of the ATB NH system to support the growth of common serovar/auxotypes makes the ATB NH system unsuitable for antibiotic susceptibility testing of N. gonorrhoeae. PMID- 9372430 TI - In-vitro activity of topoisomerase inhibitors against Pneumocystis carinii. AB - The activity of eight topoisomerase inhibitors was investigated against five clinical isolates of Pneumocystis carinii. Susceptibility tests were performed by inoculation of the organisms on to a cell monolayer and parasites were counted after 72 h incubation at 37 degrees C. Culture plates were added with Dulbecco's modified Eagle's medium containing serial dilutions of lomefloxacin, norfloxacin, ofloxacin, pefloxacin, rufloxacin, camptothecin, amsacrine and etoposide. Atovaquone, pentamide isethionate and co-trimoxazole were used as control drugs. Etoposide gave inhibition comparable to that observed with atovaquone. Poor activity was demonstrated by pefloxacin, while the other topoisomerase inhibitors had no significant effect. PMID- 9372431 TI - In-vitro photobactericidal activity of aminoacridines. AB - The toxicities of several aminoacridines were measured against pathogenic strains of both Gram-positive (Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) organisms. In several cases, illumination at a light dose of 6.3 J/cm2 resulted in considerable decreases in the minimum lethal drug concentrations required, giving up to 50-fold increases in bactericidal activity. Derivatives of 9-aminoacridine (aminacrine) exhibited phototoxicity against one or more of the test organisms, but the established photosensitizing acridines proflavine and acridine orange were photobactericidal against all strains. PMID- 9372432 TI - A 10 year survey of the antimicrobial susceptibility of urinary tract isolates in the UK: the Microbe Base project. AB - Microbe Base is a national computerized database comprising in excess of 1.7 million patient records down-loaded from the laboratory computer systems of 61 participating UK laboratories over 10 years. This paper highlights the antimicrobial susceptibilities of organisms isolated from the urinary tract which comprise around 50% of all isolates in the database. These data may be used to determine trends in antimicrobial susceptibilities; to formulate local antibiotic policies; to compare local with national data and, overall, to assist clinicians in the rational choice of antibiotic therapy and to prevent misuse, or overuse, of antibiotics. PMID- 9372433 TI - Clinical use of rifampicin during routine reporting of rifampicin susceptibilities: a lesson in selective reporting of antimicrobial susceptibility data. AB - Increased use of rifampicin for in-patients was noted after the laboratory began reporting rifampicin susceptibilities routinely for all Gram-positive bacterial isolates. The appropriateness of rifampicin use was evaluated by chart review for in-patients administered rifampicin during two time periods, before and during routine rifampicin susceptibility reporting, respectively. While rifampicin susceptibility was reported routinely, four patients were subjected to potentially harmful misuse of rifampicin. These findings reconfirm the necessity of interdepartmental consultation and extensive staff education whenever a modification of antimicrobial susceptibility profile reporting is contemplated. Furthermore, they underscore the role of the clinical microbiology laboratory in guiding antimicrobial therapy through limited reporting of susceptibility data. PMID- 9372434 TI - Influence of atmospheric conditions during incubation on the susceptibilities of Streptococcus pneumoniae isolates to five beta-lactam antibiotics. PMID- 9372435 TI - The use of Sorbarod biofilms to study the antimicrobial susceptibility of a strain of Streptococcus pneumoniae. PMID- 9372436 TI - A time-kill study to evaluate the in-vitro activity of clofazimine in combination with cefotaxime against a penicillin- and cefotaxime-resistant strain of Streptococcus pneumoniae. PMID- 9372437 TI - In-vitro activity of quinupristin/dalfopristin (Synercid) against isolates of Streptococcus pneumoniae, Staphylococcus aureus and enterococcus spp. PMID- 9372438 TI - Antimicrobial activity of LB20304, a fluoronaphthyridone, tested against anaerobic bacteria. PMID- 9372439 TI - Glycopeptide-resistant enterococci in Northern Ireland: first reported outbreak. PMID- 9372440 TI - GST-lamin fusion proteins act as dominant negative mutants in Xenopus egg extract and reveal the function of the lamina in DNA replication. AB - A cDNA encoding Xlamin B1 was cloned from a whole ovary mRNA by RT-PCR. GST-lamin fusion constructs were generated from this cDNA by first creating convenient restriction sites within the Xlamin B1 coding sequence, using PCR directed mutagenesis, and then sub-cloning relevant sequences into pGEX-4T-3. Two expression constructs were made, the first, termed delta 2+ lacked sequences encoding the amino-terminal 'head domain' of lamin B1 but included sequences encoding the nuclear localization signal sequence (NLS). The second expression construct, termed delta 2-, lacked sequences encoding the amino-terminal 'head domain' as well as sequences encoding the NLS. Purified fusion proteins expressed from these constructs, when added to egg extracts prior to sperm pronuclear assembly, formed hetero-oligomers with the endogenous lamin B3. The delta 2+ fusion protein prevented nuclear lamina assembly but not nuclear membrane assembly. The resulting nuclei were small (approximately 10 microns in diameter), did not assemble replication centers and failed to initiate DNA replication. When the delta 2- fusion protein was added to egg extracts prior to sperm pronuclear assembly, lamina assembly was delayed but not prevented. The resulting nuclei although small (approximately 12 microns), did form replication centers and initiated DNA replication. When added to egg extracts after sperm pronuclear assembly was completed delta 2+, but not delta 2-, entered the pre-formed nuclei causing lamina disassembly. However, the disassembly of the lamina by delta 2+ did not result in the disruption of replication centers and indeed these centres remained functional. These results are consistent with the hypothesis that lamina assembly precedes and is required for the formation of replication centers but does not support those centers directly. PMID- 9372441 TI - Assembly of A- and B-type lamins studied in vivo with the baculovirus system. AB - We have expressed an A-type lamin (Xenopus lamin A), a probable A-type lamin (Drosophila lamin C), two B-type lamins (Xenopus lamin LI, Drosophila lamin Dmo), and two mutants of Xenopus lamin A in Sf9 cells. All proteins were synthesized at high levels resulting in formation of paracrystals with an axial repeat of 18.5 20.0 nm by A-type lamins; in contrast B-type lamins assembled into aggregates with a fibrillar ultrastructure. Of the four wild-type proteins analyzed only lamin Dmo was found in the nuclear compartment of Sf9 cells in association with the lamina whereas the three other lamins assembled into polymers localized in the cytoplasm as well as the nucleoplasm. The Xenopus lamin A mutant lacking the complete carboxy-terminal tail assembled in the cytoplasm into long filament bundles consisting of fibrils of less than 6 nm diameter. In vitro the non helical amino-terminal head domain of lamins is required for the formation of 'head-to-tail' polymers. A lamin A mutant lacking this domain could be efficiently extracted from Sf9 cells with physiological buffers containing Triton X-100, demonstrating the importance of this domain for lamin assembly in vivo. PMID- 9372442 TI - Identification of an Spc110p-related protein in vertebrates. AB - Although varying in size and complexity, centrosomes have conserved functions throughout the evolutionary range of eukaryotes, and thus may display conserved components. In this work, we took advantage of the recent advances in the isolation of the budding yeast spindle pole body, the development of specific immunological probes and the molecular characterisation of genes involved in spindle pole body duplication or assembly. Screening a monoclonal antibody library against Saccharomyces cerevisiae spindle pole body components, we found that two monoclonal antibodies, directed against two different parts of the yeast Spc110p, decorate the centrosome from mammalian cells in an asymmetrical manner. Western blot experiments identified a 100 kDa protein specifically enriched in centrosome preparations from human cells. This protein is phosphorylated during mitosis and is tightly associated with the centrosome: only denaturing conditions such as 8 M urea were able to solubilise it. Purified immunoglobulins directed against Spc110p inhibit microtubule nucleation on isolated human centrosomes, using brain phosphocellulose-tubulin or Xenopus egg extract tubulin. This result suggested that the centrosomal 100 kDa protein could be involved in a microtubule nucleation complex. To test this hypothesis, we turned to Xenopus species, in which mAb anti-Spc110p decorated centrosomes from somatic cells and identified a 116 kDa protein in egg extract. We performed a partial purification of the gamma tubulin-ring complex from egg extract. Sucrose gradient sedimentation, immunoprecipitation and native gels demonstrated that the Xenopus 116 kDa protein and gamma-tubulin were found in the same complex. Altogether, these results suggest the existence of an yeast Spc110-related protein in vertebrate centrosomes which is involved in microtubule nucleation. PMID- 9372443 TI - Localisation of the Schizosaccharomyces pombe rho1p GTPase and its involvement in the organisation of the actin cytoskeleton. AB - The Schizosaccharomyces pombe rho1p GTPase directly activates the (1-3) beta-D glucan synthase and participates in the regulation of cell wall growth and morphogenesis in this fission yeast. Indirect immunofluorescence experiments using rho1p tagged with hemagglutinin have revealed that rho1p was located at the growing tips during interphase and at the septum prior to cytokinesis, localising to the same areas as actin patches. In S. pombe cdc10-129 mutant cells, arrested in G1, HA-rho1p accumulates at one tip whereas in cdc25-22 mutants, arrested in G2, HA-rho1p accumulates at both tips. In tea1-1 and tea2-1 cdc11-119 mutant cells, HA-rho1p is localised to the new growing tips. Overexpression of different rho1 mutant alleles caused different effects on cortical actin patch distribution, (1-3) beta-D-glucan synthase activation, and sensitivity to cell wall specific antifungal drugs. These results indicate that multiple cellular components are activated by rho1p. Overexpression of the dominant negative rho1T20N allele was lethal as was the rho1+ deletion. Moreover, when rho1+ expression was repressed in actively growing S. pombe, cells died in about 10 to 12 hours. Under these conditions, normal cell morphology was maintained but the level of (1-3) beta-D-glucan synthase activity decreased and the actin patches disappeared. Most cells lysed after cytokinesis during the process of separation, and lysis was not prevented by an osmotic stabiliser. We conclude that rho1p localisation is restricted to growth areas and regulated during the cell cycle and that rho1p is involved in cell wall growth and actin cytoskeleton organisation in S. pombe. PMID- 9372444 TI - A zinc finger protein required for stationary phase viability in fission yeast. AB - Yeast cells exit the cell cycle and enter a metabolically inert stationary phase when starved for nutrients essential for normal proliferation. We have cloned a novel gene named rsv1+ (required for stationary phase viability) that is essential for fission yeast cell viability in a stationary phase induced by glucose starvation. rsv1+ encodes a 47 kDa protein with two zinc finger motifs that are partially homologous with Aspergillus nidulans CreA, Saccharomyces cerevisiae Mig1 and mammalian EGR-1/NGFI-A. Cells deleted for rsv1+ are unable to survive glucose starvation. Transcription of rsv1+ is negatively regulated by the cAMP pathway and induced by glucose starvation. Cells with the constitutively activated cAMP pathway are known to lose viability when grown to confluence or when starved for glucose. These cells are poor in rsv1+ induction and their viability loss is largely suppressed by ectopic expression of rsv1+. Thus, poor induction of rsv1+ is at least partially responsible for the viability loss. Analysis also showed that cells need to receive starvation signals before entry into the stationary phase in order to maintain viability in a glucose-poor environment. PMID- 9372446 TI - The centrosomal protein centrosomin A and the nuclear protein centrosomin B derive from one gene by post-transcriptional processes involving RNA editing. AB - The identification of a gene encoding concomitantly a nuclear protein and an intrinsic centrosomal protein further emphasizes the close and presumably developmental relationship between the cell nucleus and the centrosome. Screening of a murine RNA-based cDNA library with an antiserum to a centrosomal protein and rescreening with the insert of an initial clone released two complete cDNAs (1.2 kbp and 2.2 kpb) coding for proteins with notable characteristics. The amino terminal sections of centrosomin A (276 amino acid residues, molecular mass 34.5 kDa) and of centrosomin B (447 amino acid residues, molecular mass 54.8 kDa) are identical over 272 amino acid residues. The carboxy-terminal section of the larger protein comprises additional 175 amino acid residues including nuclear location signals. The mRNAs encoding centrosomin A and B derive from a single gene. Chromogenomic DNA as template and primer pairs complementary to the sequence which is identical in centrosomin A and B cDNAs results in amplification of only one DNA fragment. Moreover, one exon of the genomic sequence and the centrosomin B-encoding cDNA sequence include a G which is deleted in the centrosomin A-encoding cDNA. Accordingly, the two mRNAs are the products of either alternative splicing or alternative polyadenylation in combination with RNA editing. The recombinantly expressed chimeric protein consisting of centrosomin A and the green fluorescent protein from Aequorea victoria accumulates in centrosomes while the corresponding fusion protein with the centrosomin B sequence is transported into nuclei. PMID- 9372445 TI - Cyclic nucleotides in glutamate chemosensory signal transduction of Paramecium. AB - Glutamate is an attractant stimulus to Paramecium tetraurelia. It causes a hyperpolarization of the cell and smooth, relatively fast swimming that is characteristic of hyperpolarizing stimuli. We show here that by 1-30 seconds of stimulation, glutamate increases intracellular cAMP. Interestingly, other attractant stimuli, such as acetate and NH4Cl, that similarly hyperpolarize the cell do not induce an increase in cyclic AMP observable at 30 seconds. In order to determine whether the changes in cyclic AMP could be rapid enough to participate in stimulation as compared to slower processes such as adaptation, rapid kinetic measurements of cyclic AMP were made on whole cells by quenched flow. We found that, in cells stimulated with glutamate, intracellular cyclic AMP increases by 30 mseconds and peaks at about sevenfold over basal levels by 200 mseconds. Cyclic GMP does not change relative to basal levels over rapid or slower time courses of glutamate stimulation. An antagonist of glutamate, IMP, depolarizes the cells and decreases intracellular cyclic AMP by approx. 50% and slightly increases cyclic GMP. Results of behavioral tests of cells treated with protein kinase inhibitors also suggest that cyclic AMP is part of the signal transduction pathway for glutamate, but not for other attractant stimuli. These studies are the first demonstration of a possible role for cyclic nucleotide second messengers in an attractant chemosensory transduction pathway in Paramecium. PMID- 9372447 TI - Extinction of immunoglobulin gene expression in B cells upon fusion with HeLa cells is preceded by rapid nuclear depletion of essential transcription factors and is accompanied by widespread inactivation of genes expressed in a B cell specific manner. AB - When immunoglobulin (Ig) expressing B cells are fused with non-B cells, Ig expression is rapidly suppressed at the level of transcription, a phenomenon termed extinction. Here we demonstrate that fusion of HeLa cells with either diploid or tetraploid B cells (Daudi) results in widespread extinction of several other B cell-encoded genes that are expressed in a B cell-specific manner. In contrast, expression of B cell-expressed genes that are not dependent on cell specific controls is unaffected. We show that the molecular mechanism(s) underlying Ig gene extinction can be explained, at least in part, by a lack of transcription factors that are essential for Ig gene transcription. These transcription factors are either not produced due to block of transcription of their respective genes (Oct-2, OBF-1, PU.1), or are rendered inactive posttranslationally (NF-kappa B, E47). By isolating Daudi x HeLa heterokaryons a few hours after fusion, we have studied the initial fate of two B cell-specific transcription factors involved in Ig gene transcription, Oct-2 and NF-kappa B. This report provides the first demonstration that upon fusion with HeLa cells, the nuclear contents of B cell-expressed transcription factors are depleted within a few hours with kinetics that are as fast or faster than that of Ig gene extinction. Thus, the extinguishing mechanism is effective very early after fusion. We suggest that extinction of Ig genes is part of a global mechanism that suppresses the differentiation program foreign to the HeLa phenotype. PMID- 9372448 TI - Defective phototransductive disk membrane morphogenesis in transgenic mice expressing opsin with a mutated N-terminal domain. AB - Retinitis pigmentosa is a heterogeneous group of inherited retinal disorders in which the photoreceptor cells degenerate. A line of transgenic mice expresses a mutant opsin gene that encodes three missense mutations near the amino terminus, including P23H, which is the basis for a common form of dominant retinitis pigmentosa. By studying the photoreceptor cells of these mice and their normal littermates, we found that: (1) opsin was routed correctly, (2) the concentration of opsin in the disk membranes appeared normal by freeze fracture analysis, (3) the amount of disk membrane shedding was normal, but (4) the basal disks of the outer segments were disorganized, indicating defective disk membrane morphogenesis. Defective disk membrane morphogenesis appears to result in the formation of fewer mature disks, thus accounting for observed gradual shortening of the photoreceptor outer segments with age. We suggest that abnormal disk membrane morphogenesis is the primary cellular defect that leads to blindness, and that it arises from the inability of nascent disk membranes, containing normal and mutant opsin, to interact normally with each other. PMID- 9372449 TI - Onset of gluconate-H+ symport in Schizosaccharomyces pombe is regulated by the kinases Wis1 and Pka1, and requires the gti1+ gene product. AB - In the fission yeast Schizosaccharomyces pombe, glucose represses onset of gluconate-H+ symport and inhibits transiently the activity of the symport protein. Wild-type cells harvested from high glucose medium take up gluconate very slowly and the rate of uptake is increased 150-fold in response to glucose starvation. Here it is shown that an intact cAMP cascade is necessary to prevent premature onset in the presence of high glucose concentrations. Cells which have lost either adenylate cyclase (Cyr1) or cAMP-dependent protein kinase (Pka1) transport gluconate up to 60-fold faster than wild-type cells when harvested from high glucose medium. Moreover, inactivation of the stress-sensing Wis1-Sty1 MAP kinase pathway, by loss of Wis1 MAP kinase kinase, diminishes 10-fold the onset of gluconate uptake in response to starvation. A mutant was identified showing a comparable phenotype. By complementation, the gti1+ (gluconate transport inducer 1) gene has been isolated. Disruption of gti1 reduces starvation-induced onset by a similar factor to that observed in wis1 delta cells. Cells over-expressing gti1+ induce gluconate uptake much faster resulting in a threefold higher uptake rate, although gti1+ does not code for the gluconate transport protein. In contrast to the repression of onset, transient downregulation of the gluconate symporter is independent of Pka1 activity and requires ongoing glucose influx. Addition of glucose to starved cyr1 delta cells reduces uptake 9-fold, whereas starved pka1 delta cells, which are able to synthesise cAMP, respond with a 60 fold decrease in transport. PMID- 9372450 TI - Commitment to differentiation and cell cycle re-entry are coincident but separable events in the transformation of African trypanosomes from their bloodstream to their insect form. AB - African trypanosomes undergo extensive changes in cellular morphology, biochemistry and surface antigen expression as they differentiate from their bloodstream form to those forms that colonise the midgut of their tsetse fly vector. If initiated with stumpy-form cells, a non-dividing sub-type of the bloodstream parasite, differentiation and cell cycle re-entry occur synchronously in the population and provide a means to dissect the respective controls of proliferation and transformation. We have exploited this synchrony to determine the respective importance and hierarchy of the known triggers for differentiation (cis aconitate, temperature drop) for individual components of both differentiation and the cell cycle. This has revealed the pre-eminence of cis aconitate as a primary trigger for parasite differentiation, and has allowed us to determine that the cellular commitment to both differentiation and cell-cycle re-entry are precisely co-incident processes. PMID- 9372451 TI - Epitopes of adhesion-perturbing monoclonal antibodies map within a predicted alpha-helical domain of the integrin beta 1 subunit. AB - Several recent studies have demonstrated the involvement of various domains of the beta 1 integrin subunit in ligand binding. Thus, specific amino acids have been shown to be important in divalent cation binding, and others have been implicated by peptide crosslinking to play an intimate role in integrin-ligand interactions. Added to these data are previous observations that a group of adhesion-blocking anti-chicken beta 1 antibodies mapped within the first 160 amino acid residues of the subunit. These observations suggested that this region plays a critical role in integrin ligand recognition. In order to further define the domain in which the epitopes for these antibodies are clustered, a series of mouse/chicken chimeric beta 1 constructs were examined for their reactivity with each of these antibodies. Most of the antibodies recognize a region between residues 124 to 160 of the chicken beta 1 subunit. Computer modeling predicted a possible amphipathic alpha-helical configuration for the region between residues 141 to 160. Consistent with this prediction, circular dichroism and NMR analysis revealed a tendency for a synthetic peptide containing these residues to form an alpha-helix. The significance of this structural characteristic was demonstrated by a mutation at residue 149 that disrupted the alpha-helix formation and resulted in a loss of the ability to form heterodimers with alpha subunits, localize to focal contacts, or be transported to the cell surface. The direct involvement of residues 141 to 160 in ligand binding was supported by the ability of a peptide with this sequence to elute integrins from a fibronectin affinity column. Thus, our data suggest that residues 141 to 160 of the integrin beta 1 subunit, when arranged in an alpha-helix configuration, participate in ligand binding. PMID- 9372452 TI - The latency associated transcripts (LAT) of herpes simplex virus: still no end in sight. AB - The herpes simplex virus latency associated transcripts (LAT) are the only viral gene products that accumulate to a high concentration in the trigeminal ganglia (TG) of latently infected animals. Their abundance is particularly surprising, since they are thought to be the introns of a larger, approximately 8.3 kb precursor. LAT are not linear molecules. Therefore they are either a circle or a lariat that is not debranched. This structure could explain their unusual high stability. Moreover, the functional potential of stable, nuclear RNA has been demonstrated in other biological systems and could offer a clue as to the mechanism of action of LAT. Therefore, the non-linear nature of LAT and functional implications mean that both literally and figuratively, there is no end in sight for this unusual molecule. PMID- 9372453 TI - Efficient gene transfer into primary and immortalized human fetal glial cells using adeno-associated virus vectors: establishment of a glial cell line with a functional CD4 receptor. AB - Adeno associated virus (AAV) is a non-pathogenic dependent parvovirus with a broad host range, capable of high levels of transduction and stable integration into the host cell genome. We have investigated the potential for using AAV as a vector for gene transfer into glial cells of the human fetal nervous system. Recombinant AAV vectors expression either the reporter gene beta-galactosidase or a human CD4 receptor were able to transduce both primary glial cells of the human fetal nervous system and an SV40 immortalized human fetal glial cell line (SVG). No difference in transduction efficiency was observed between the primary cells and the cell line which in both cases was as high as 95%. Stable transfectants of the glial cell line expressing the CD4 receptor were selected. An SVG/CD4 expressing line was then established. The presence of the CD4 receptor was confirmed by immunohistochemistry, Westerm immuno-blotting and flow cytometric analysis. The CD4 receptor was shown to be functional by infection of the SVG/CD4 cell line with the human immunodeficiency virus (HIV). Upon infection, the SVG/CD4 cells produced 20-fold higher levels of the HIV intracellular core antigen P24 than the CD4 negative parental cells and in addition formed syncytia. The use of AAV vectors should prove useful in biological investigations of human glial cells and offers promise as a means of ex vivo and in vivo gene delivery. PMID- 9372454 TI - HIV-1 LTR DNA sequence variation in brain-derived isolates. AB - Isolates of human immunodeficiency virus (HIV-1) derived from the central nervous system (CNS) display properties distinctive from blood-derived isolates, including a high incidence of macrophage tropism in CNS isolates. Macrophage tropism is a result, in part, of DNA sequence variation in the HIV-1 envelope glycoprotein gene, but evidence also exists suggesting differences in the long terminal repeat (LTR) may contribute to differential gene expression. To investigate the nature of HIV-1 LTR sequence variation in the brain, we have sequenced bases -374 to +43 of the LTR from the brains of four HIV-1-infected patients. A total of 56 clones were derived from either both gray and white matter (three brains) or white matter alone (one brain), and these sequences were compared to 17 published sequences derived from multiple sources. A total of five LTR quasispecies were found. Overall, there was a significant amount of sequence variation both within and between brains, comparable to that seen in quasispecies of the envelope glycoprotein derived from blood or brain. The vast majority of the variation was seen in regions upstream from the two NF-kappa B sites. Compared to the blood-derived, T cell-tropic IIIB LTR, a majority of clones from two or more of the brains shared 11 unique substitutions in transcription factor binding sites, of which eight were shared with the CNS-derived clones JR-CSF and JR-FL and altered the NF-AT and LEF-1 transcription factor binding sites. These findings correlate with published functional studies showing CNS-derived HIV-1 LTRs are distinct from the blood-derived IIIB LTR, and represent a starting point for future studies designed to determine which LTR sequence variations are associated with cell-specific differences in gene expression in the CNS. PMID- 9372455 TI - Regulation of glutathione and cell toxicity following exposure to neurotropic substances and human immunodeficiency virus-1 in vitro. AB - The aim of the present study was to assess the toxic potential of drugs of abuse and other neuropharmacological agents in the pathogenesis of AIDS dementia complex (ADC), the neurological complication of AIDS. Neuroblastoma and glioblastoma cell lines expressing the dopamine transporter, as well as primary macrophages exposed to human immunodeficiency virus-1 (HIV-1), were used to investigate the possibility of any synergistic effect between the mode of toxicity of such substances and virus exposure. The drugs of abuse used in our experiments were cocaine and morphine, which exert their action, among others, on the dopaminergic system. Effects were compared to treatment with dopamine itself and a typical dopaminergic drug used pharmaceutically, selegiline. In macrophage cultures, glutathione (GSH) was upregulated strongly after treatment with dopamine, morphine or selegiline, and this effect was enhanced when cells were pre-exposed to virus. This upregulation is discussed as a compensatory reaction to an oxidative signal. When hydrogen peroxide plus iron sulfate was used as a strong oxidant in macrophages, GSH concentrations decreased as a result of cell injury. Cell numbers remained constant in all treatment groups. In contrast, in both neuroblastoma and glioblastoma cell lines, the modulation of GSH concentrations by neurotropic substances was accompanied by significant cell loss, which was exacerbated by HIV-1 pretreatment. Selegiline did not change cell numbers when incubated alone. However, when incubated following treatment with HIV-1 cell death was highly significant. Ascorbic acid (AA), included as antioxidant, totally restored cell loss in cultures treated with dopamine. However, no effect was observed in combined treatment of AA and morphine or selegiline. The results demonstrate a synergistic role in cellular toxicity due to neurotropic substances and HIV-1, and suggest that neuropharmacological agents may contribute to the pathogenesis of ADC. PMID- 9372457 TI - Neuropathology in cats experimentally infected with feline immunodeficiency virus: a morphological, immunocytochemical and morphometric study. AB - Neuropathological changes have been described associated with feline immunodeficiency virus (FIV) infection. The objective of our study was to characterize the lesions found in the brain and spinal cord of experimentally FIV infected cats and to quantify, by morphometric analysis, the intensity of gliosis found in these subjects at different time post infection (pi). The brains and spinal cords appeared grossly normal. Gray matter of cortical and subcortical structures showed a moderate to pronounced gliosis particularly in all cerebral cortex and hippocampus. Morphometric analysis demonstrated that GFAP immunoreactivity was markedly higher in infected animals. Gliosis was present 15 days pi and did not appear to progress during the infection, whereas neuronal changes when present were observed only in long-term infected animals (15-23 months pi). In a large proportion of infected cats a diffuse gliosis of white matter and vacuolar myelinopathy was also present. Despite some discrepancies observed between neuropathological changes in FIV-infected animals and HIV infected individuals, the presence in the cerebral cortex of cats with FIV infection of alterations similar to those observed in AIDS patients demonstrates that FIV is an interesting animal model particularly that may be useful for clarifying the pathogenesis of neuropathological changes associated with HIV infection. PMID- 9372456 TI - Semliki Forest virus infection leads to increased expression of adhesion molecules on splenic T-cells and on brain vascular endothelium. AB - Semliki Forest virus A7 (SFV-A7) is a neurotropic alphavirus that leads to an asymptomatic encephalitis in adult immunocompetent mice. We studied the expression of leukocyte and endothelial cell adhesion molecules in the spleen and in the central nervous system (CNS) during SFV-A7 infection. Kinetics of the expression of LFA-1 alpha/CD11a, LFA-1 beta/CD18, Mac-1/CD11b, VLA-4/CD49d, ICAM 1/CD54 and L-selectin/CD62L was determined on splenic CD4+ and CD8+ T-cells and macrophages by flow cytometry. Time course of the expression of these antigens and VCAM-1/CD106 as well as viral antigens in the CNS was studied by immunoperoxidase staining. In the spleen, a sustained increase in LFA-1 expression and a temporary increase at day 7 in the expression of VLA-4, Mac-1 and ICAM-1 were detected on CD8+ T-cells. L-selection was down-regulated on CD4+ cells. Adhesion molecules on macrophages remained unchanged. In the CNS, expression of Mac-1+, VLA-4+ and LFA-1+ cells increased in parallel with the kinetics of the expression of their ligands ICAM-1 and VCAM-1 on brain vessels. Upregulation of adhesion of molecules peaked between days 5-8 and was most prominent in the cerebellar and brain stem white matter where viral antigens were most abundant. We conclude that the adhesion molecules profile of splenic T cells is altered during SFV-A7 infection which may influence their homing into the CNS. Macrophages are probably recruited non-specifically as a consequence of activation of the brain vascular endothelium in the inflamed areas of the brain. PMID- 9372458 TI - Reduction of voltage-dependent calcium currents in mumps virus-infected cultures of rat hippocampal neurons. AB - The effects of a mumps virus infection on functional properties of embryonic hippocampal neurons in culture were analysed with special emphasis on voltage dependent Ca2+ channels. Cultures with higher or lower density of glial cells (not treated or treated with mitotic inhibitor, respectively) were infected with the relatively non-cytolytic RW strain of mumps virus and currents were recorded from neurons using whole cell voltage clamp. More than 65% of neurons and glial cells contained viral antigens 1-2 days post infection (p.i.). Glial cells remained infected 6-7 days p.i., while the ratio of infected versus uninfected neurons, especially in cultures with higher glial cell density, was reduced. In both infected and uninfected cultures the somal voltage-dependent Ca2+ currents were stronger in cultures with a higher glial cell density, which indicates that these currents are influenced by glial cells. Introduction of the virus into cultures caused a selective decrease in inward Ca2+ currents, which was most marked at days 6-7 p.i., and which included both infected and unifected neurons. Spontaneous synaptic currents and other ion channel conductances appeared normal in the infected cultures. Dantrolene, which inhibits release of Ca2+ from intracellular stores, decreased the neurons that died during the infection. Taken together the results show that a mumps viral infection can selectively alter the number of function of somal voltage dependent Ca2+ channels in immature hippocampal neurons and that this may reflect a disturbed glia-nerve cell interaction. PMID- 9372459 TI - Involvement of CD4+ cells in the protection of C58 mouse against polioencephalomyelitis induced by lactate dehydrogenase-elevating virus. AB - Immunosuppression, occurring naturally with aging, or experimentally after cyclophosphamide treatment or irradiation, is required for the development in C58 mice infected with lactate dehydrogenase-elevating virus (LDV) of a severe polioencephalomyelitis that is caused by viral destruction of anterior horn neurons. Here it is shown that depletion of T helper lymphocytes by administration of an anti-CD4 antibody was followed by a progressive paralysis typical of polioencephalomyelitis in C58/J mice inoculated with a neurovirulent strain of LDV. Although it was clear that other cell subsets are also required to assure complete protection of genetically-susceptible mice, our results show that T helper lymphocytes play a major role in the prevention of LDV-induced polioencephalomyelitis. The mechanisms by which these cells confer this protection remain however to be determined. PMID- 9372460 TI - A 10-year follow-up study of fixed metal ceramic prosthodontics. AB - The aim of this retrospective study was to record patients' satisfaction with fixed metal ceramic bridges and crowns made by dental students and to evaluate the functioning and condition of the bridges and crowns clinically and radiologically. Out of the 60 patients treated at the Institute of Dentistry during 1984-85, 30 patients attended the follow-up examination (16 women, mean age 39, range 23-62 years and 14 men, mean age 44, range 26-65 years). The anamnestic data and data regarding treatment procedures were collected from the patient files. The patients had been supplied with 41 crowns and 24 bridges (mean 3.9 units, range 3-6 units), which included 61 abutments and 33 pontics or cantilever extensions (abutment/pontic ratio 1.85: 1). Marginal fidelity was unsatisfactory in 13% of the crowns and bridges and gingival bleeding and pockets of 4-6 mm were noted in 27% and 12% of cases, respectively. None of the subjects had caries in the abutments. PMID- 9372461 TI - Outcome of therapy in the conservative management of temporomandibular pain dysfunction disorder. AB - The present study considered predictors of the outcome of treatment for temporomandibular pain dysfunction disorder (TMPD). Thirty-seven patients were assessed with objective and self-report measures of physiological and psychosocial aspects of this disorder at initial assessment and at 6-month follow up subsequent to conservative physical therapy. Patients were subdivided into slow and rapid responders to conservative physical therapy based on self-reported level of improvement. Measures employed included the Temporomandibular Pain Dysfunction Disorder Questionnaire and the Temporomandibular Pain Dysfunction Disorder Clinical Form. Eighty-one per cent of patients showed a 50% or greater improvement in pain severity at follow-up, with minimal differential changes across the two groups found in the physiological symptoms, while the rapid responding group showed greater improvement in terms of psychosocial factors. These findings indicated that psychosocial factors, particularly coping strategies and illness behaviour, cannot be ignored in the management of TMPD. PMID- 9372462 TI - Occlusal contacts in maximum intercuspation in normal dentitions. AB - A cross-sectional study of the contacts in maximum intercuspation was undertaken using a method to identify occlusal contacts, which is indicated as satisfactory by modern research. The aims were to describe in subjects with normal dentitions and normally functioning masticatory systems: (a) the general distribution of contacts; (b) the numbers in the various classes and types of occlusal contacts; (c) the numbers of teeth without contact. A randomized sample of 18 women and 20 men was used. Classical theoretical proposals for the numbers, distribution and nature of occlusal contacts were not supported. Wide variability was evident and asymmetry of distribution on the right and left sides of individual subjects was common. Contacts with stabilizing tendencies involved the mandibular supporting cusps in 79% of occurrences. Overall, the difference in the number of contacts with stabilizing effects was not significantly different from the number with unstabilizing tendencies. Contacts with mechanically unstabilizing effects did not produce clinically discernible, unfavourable sequelae in the dentitions. Because of the sparse number of stabilizing contacts, interventions involving the occlusal surfaces should maintain or improve on the number of such contacts in maximum intercuspation. PMID- 9372463 TI - Myoelectrical activity of clinical rest position and jaw muscle activity in young adults. AB - Electromyographic activity of anterior temporal, superficial masseter, deep masseter and anterior digastric muscles was measured in 40 young healthy men and women during rest (at the beginning and the end of tests), clench, maximal opening, lateral displacement and CR manipulation. During initial rest position myoelectrical activity was 1.9 microV increasing to 2.1 microV at the end of tests (P = 0.08). During clench and maximal opening no significant differences between the sexes were found. The digastric muscle showed considerable activity during maximal opening, lateral displacement and CR manipulation. PMID- 9372464 TI - Pain and other cardinal TMJ dysfunction symptoms: a longitudinal survey of Japanese female adolescents. AB - Longitudinal data were obtained for 4 years from 361 Japanese high school girls between the ages of 12 and 16. The data were analysed for the occurrence of pain and its associations with the occurrence of other cardinal TMJ dysfunction symptoms and occlusal states. It was determined that even if pain or noise or jaw deviation symptoms appeared, those symptoms did not necessarily last thereafter. The symptoms were not persistent but rather appeared and disappeared repetitively. Those who exhibited noise during at least one of the surveys of the 4-year survey period showed a significantly higher prevalence of pain than those who did not exhibit noise at all (P < 0.05). Those who exhibited noise by the age of 13 showed a significantly higher prevalence of pain than those who exhibited noise after age 14 (P < 0.1). The temporal occurrence of pain depended upon the appearance of noise and the age at which noise first appeared. On the other hand, the occurrence of pain symptoms was not necessarily related to specific types of malocclusions, which suggests the significance of multifactorial contributions in understanding the aetiology of pain rather than the occlusal factor. PMID- 9372465 TI - Effect of dental base metal alloys on IgE levels and some blood parameters. AB - Despite the widespread use of nickel-based alloys, claims for safety of these alloys have not yet been accepted universally. The allergenic effects of nickel on dental patients and the potential toxic effects of nickel and beryllium on laboratory technicians continue to cause concern within the dental profession. The purpose of this study was to investigate immunoglobulin type E (IgE) values and some blood parameters of dental laboratory technicians who use dental base metal alloys. The following two groups were studied: 19 students who had been working with dental base metal alloys for two years; and 21 pre-clinical students who had never worked with dental base metal alloys. The latter group were used as a control. Blood specimens were taken from both groups and analysed using The Blood Counter. Total erythrocyte, thrombocyte, leukocyte, lymphocyte, granulocyte and monocyte counts were determined. Measurement of IgE was made with Coat-A Count Total IgE IRMA. Blood and IgE measurements were repeated after 8 months. In the experimental group both erythrocyte and thrombocyte values were found to be statistically significantly decreased compared with the control group. No significant differences were found in lymphocyte and monocyte numbers between the initial and later measurements. There were no significance changes in IgE values for both groups. These results provide no evidence that dental base metal alloys (Ni, Cr, Be, Co) caused an increase in sensitization, during the period of the study. PMID- 9372466 TI - An evaluation of self-cured and visible light-cured denture base materials when used as a denture base repair material. AB - The aim of this study was to compare some of the physical properties of a heat cured, a self-cured and a visible light-cured acrylic resin, and to evaluate the suitability of visible light-cured resin as a repair material for dentures made of heat-cured acrylic resin. Transverse strength, surface hardness and impact strength were determined for the three materials and the efficiencies of light cured and self-cured resins, when used as a repair material, were evaluated by testing the transverse strength of repaired heat-cured specimens 1 hour, 1 week and 1 month after repair. The results showed that the rigidity of specimens repaired with light-cured resin improved with longer water storage. However, their transverse strength reached a maximum after one day and was reduced after 1 month. The rigidity and transverse strength of specimens repaired with self-cured resin were not influenced significantly by water storage and the transverse strength was significantly higher than the light-cured repaired specimens. PMID- 9372467 TI - Setting properties of alginate impression materials in dynamic viscoelasticity. AB - The viscoelastic properties of three alginate impression materials were investigated. A landmark of working time was calculated using a raw phase-time curve. A landmark of setting time was calculated from an inflection point of the divided difference of the first order in the share modulus-time curve. As a result, the working time was common at the point of delta = 45 degrees in variable frequencies. The mean value was obtained with less deviation. The setting times obtained were similar for variable frequencies. The mean values showed a distinct difference for each impression material. PMID- 9372468 TI - Proximo-cervical adaptation of Class II-composite restorations after thermocycling: a quantitative and qualitative study. AB - Sixty caries-free extracted human molars were used to determine the proximo cervical adaptation and sealing of Class II-composite restorations related to the location of the cavity margins: 1.0 mm or 0.5 mm coronal to the cementum-enamel junction (CEJ), at the CEJ, and 0.5 mm apical to the CEJ. All cavities were filled with a hybride type composite resin, which was combined at the CEJ and apical to the CEJ with a dentine adhesive in half of the specimens. The proximo cervical adaptation and sealing was determined before and after thermocycling (TC, 2000 cycles, 5-55 degrees C) by SEM and dye penetration tests. Furthermore, an analysis of the interfaces between the enamel or dentine and the filling material was performed to determine whether or not there is a significant correlation between micromorphological factors of the dental hard tissues (enamel acid etch pattern, dentine resin tag pattern) and the marginal adaptation of the composite restorations. The data were statistically evaluated by means of H-tests (Kruskall-Wallis), U-tests (Mann-Whitney), and Chi2-tests (P < 0.05). It was found that the proximo-cervical adaptation is statistically significant dependent on the position of the margin. 1.0 mm coronal to the CEJ an excellent marginal sealing was found before and after TC, whereas all other groups revealed a significant deterioration of the marginal integrity after TC. Using a dentine adhesive significantly improved the marginal sealing in cavities at the CEJ before and after TC, however the marginal quality was not achieved as in the case of the normally structured enamel 1.0 mm coronal to the CEJ following acid etching. In defects 0.5 mm apical to the CEJ the dentine adhesive only improved the cervical adaptation before TC. The evaluation of the tooth/filling interfaces revealed that there is no statistically significant correlation between the enamel acid etch pattern resp. dentine resin tag pattern and the marginal sealing. PMID- 9372469 TI - The coronoid process as a cause of mandibular hypomobility--case reports. AB - In an attempt to draw the clinician's attention to the coronoid process site while evaluating the aetiology of the restriction of mandibular opening, four cases are illustrated. These cases represent a diversity of causes hampering the free rotational movement of the coronoid process in space during jaw function. Case 1 is an example of unilateral hyperplastic coronoid process and osteochondroma; case 2 shows unusually shaped short and divergent coronoid processes combined with a bucally displaced maxillary third molar on one side; cases 3 and 4 represent an anatomical variation of an extremely narrow vestibular space due to the close proximity of the medial aspect of the coronoid process to the distal molar. It is suggested that each clinical examination include the width of the buccal vestibular space while performing mandibular movements. PMID- 9372470 TI - Bilateral coronoid hyperplasia--a report with a view on its management. AB - Bilateral coronoid hyperplasia requires surgery (coronoidectomy) to improve mouth opening. An intra-oral approach is preferred with direct fibre-optic anaesthetic intubation. Myotomy of the masseter muscle is recommended in cases where fibrotic and calcifying effects have occurred. Pre-operative physiotherapy counselling and post-operative jaw exercises are important to the final success of the management. PMID- 9372471 TI - Existence of Candida albicans and microorganisms in denture stomatitis patients. AB - The aetiology of denture stomatitis is not clear from the literature. Some studies show its aetiology as Candida albicans, while other reports point out the significance of microorganisms. In this study the existence of C. albicans and microorganisms was investigated in subjects with and without denture stomatitis. The results showed that a combination of C. albicans and microorganisms is more likely to be responsible for denture stomatitis. PMID- 9372472 TI - Altered loading patterns and femoral bone mineral density in children with unilateral Legg-Calve-Perthes disease. AB - Maximization of bone accrual during the growing years is thought to be an important factor in minimizing fracture risk in old age. Mechanical loading through physical activity has been recommended as a modality for the conservation of bone mineral in adults; however, few studies have evaluated the impact of different loading regimes in growing children. The purpose of this study was to compare bone mineral density (BMD) in weight-bearing and non-weight-bearing limbs in 17 children with unilateral Legg Calve Perthes Disease (LCPD). Children with this condition have an altered weight-bearing pattern whereby there is increased mechanical loading on the noninvolved normal hip and reduced loading on the involved painful hip. Thus, these children provide a unique opportunity to study the impact of differential mechanical loading on BMD during the growing years while controlling for genetic disposition. BMD at four regions of the proximal femur (trochanter, intertrochanter, femoral neck, total of the regions) was measured using dual energy x-ray absorptiometry (DXA), and the values were compared between the involved and noninvolved sides of the children with LCPD. The BMD of the both sides also were compared with normative values based on both chronological and skeletal age data. A significantly higher BMD was found on the noninvolved side over the involved side for all regions (P < 0.01 and percentage differences of 12-15%) except at the femoral neck (percentage difference of 3.9%). The BMD (at all regions) of the noninvolved side also was significantly greater (P < 0.01) than either the chronological or skeletal age based norms for all sites except the trochanter. The results support the concept that mechanical loading of the skeleton during the growing years is an important factor in BMD accrual. PMID- 9372473 TI - Influence of sports discipline on shoulder rotator cuff balance. AB - Isokinetic shoulder rotational strength was evaluated in four groups of subjects as follows: 12 nonathletes, 12 runners, 15 tennis players, and 12 baseball players for a total of 51 subjects. The tests were performed in the seated 45 degrees abducted test position in the scapular plane at 60, 180, and 300 degrees.s-1 for both shoulders. Peak torque and mean power values were gathered, and from these values the internal/external rotation ratios were calculated. Intergroup comparison showed a progression of the ratio related to the sports discipline. The nonathletes and runners had ratios close to those reported for nonathletes (1.3 to 1.5). The tennis players had ratios close to 1.5, whereas the baseball players had ratios from 1.6 to 2.2. The comparison between dominant and nondominant side showed no significant differences in the tennis players and higher values for the dominant side in the nonathletes and runners under certain conditions (180 degrees.s-1 for the nonathletes and 300 degrees.s-1 for the runners). Regarding the baseball players, the ratio was systematically higher for the dominant side. These results raise questions about the influence of sports discipline on the internal/external rotator muscle ratio and indicate the need to establish normative values based on the characteristics of the population under study. PMID- 9372474 TI - Anterior cruciate ligament reconstruction and joint dynamics during stair climbing. AB - Athletes with anterior cruciate ligament (ACL) deficiencies exert decreased knee extension moments during level walking (quadriceps avoidance gait), and yet within a few months of ACL reconstruction they are often expected to return to competitive sport. To investigate this issue further, 10 normal subjects and seven ACL deficient patients were evaluated both pre- and post-operatively (mean follow-up of 6 months), and each performed multiple trials ascending a staircase which consisted of three steps. Bilateral joint angles, moments, powers, and work were measured and the data were ensemble averaged and statistically analyzed (repeated measures ANOVA with significance level set at 0.05). Anterior-posterior knee laxity decreased significantly (from 7.9 mm to 5.8 mm) while subjective knee function also improved following ACL reconstruction (knee score increased from 70.4 to 88.5). Pre-operatively, there were no statistically significant differences in biomechanical parameters between the patients' ACL-deficient and intact sides and the normal subjects. Post-operatively, however, statistically significant reductions were seen for the peak moment (91.9 vs 22.5 Nm), power (181 vs 84 W), and work performed (28.0 vs -5.6 J) at the injured knee, which was also the knee from which the patellar tendon graft had been harvested. These reductions were accommodated by significant increases in excursion, moment, and power at the contralateral ankle joint. The results indicate that while the ACL reconstruction were successful in restoring anterior-posterior knee stability, the decrease in knee power and work performed post-operatively by the injured (i.e., donor) knee suggests that donor site morbidity may need to be critically evaluated over a long-term period. PMID- 9372475 TI - Lipids and lipoproteins in diet and exercise. Introduction. PMID- 9372476 TI - The poloxamer 407-induced hyperlipidemic atherogenic animal model. AB - We are attempting to develop a chemically-induced murine model for the study of atherosclerosis. Injection of poloxamer-407 (P-407) into rats and mice causes significant dose-dependent hypercholesterolemia and hypertriglyglyceridemia. The elevated triglycerides (TG) seem to result primarily from the compound's inhibition of lipoprotein lipase. P-407 also indirectly stimulates the activity of the rate limiting enzyme in cholesterol (CHOL) biosynthesis, HMG CoA reductase. In addition, P-407 promotes changes in the concentration of hepatic CHOL content. These date indicate that the hyper CHOL could be the result of increased CHOL synthesis, as well as a clearing of CHOL from the liver. Chronic injection into mice of P-407 for 145 d produced atherogenic lesions in the aortas of C57BL/6 mice. The response was equivalent to that seen in animals eating a high CHOL diet for 145 d. Cholic acid potentiated the P-407-induced atherogenesis. These data suggest that P-407 could be used as an agent for the study of hyperlipidemia-induced atherogenesis. PMID- 9372477 TI - Regulation of plasma lipoprotein levels by dietary triglycerides enriched with different fatty acids. AB - Saturated vegetable oils (coconut, palm, and palm kernel oil) containing predominantly saturated fatty acids, lauric (12:0) or myristic (14:0 and palmitic (16:0), raise plasma total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) levels in animals and humans, presumably by decreasing LDL receptor activity and/or increasing LDL-C production rate. Although stearic acid (18:0) is chemically a saturated fatty acid, both human and animal studies suggest it is biologically neutral (neither raising nor lowering) blood cholesterol levels. Although earlier studies indicated that medium chain fatty acids (8:0-10:0) were also thought to be neutral, more recent studies in animals and humans suggest otherwise. Unsaturated vegetable oils such as corn, soybean, olive, and canola oil, by virtue of their predominant levels of either linoleic acid (18:2) or oleic acid (18:1), are hypocholesterolemic, probably as a result of their ability to upregulate LDL receptor activity and/or decrease LDL-C production rate. Whether trans fatty acids such as trans oleate (t18:1), in hydrogenated products such as margarine, are hypercholesterolemic remains controversial. Studies in humans suggest that their cholesterol-raising potential falls between the native nonhydrogenated vegetable oil and the more saturated dairy products such as butter. Assessment of the magnitude of the cholesterolemic response of trans 18:1 is difficult because in most diet studies its addition is often at the expense of cholesterol-lowering unsaturated fatty acids, making an independent evaluation almost impossible. PMID- 9372479 TI - The swine as a model for studying exercise-induced changes in lipid metabolism. AB - The swine has many similarities to humans, making it an excellent research model in which to study the role of exercise on lipid metabolism. Swine adapt to exercise-training by increasing muscle oxidative enzymes, maximal stroke volume, cardiac output, VO2max, and high density lipoprotein cholesterol levels, while decreasing total cholesterol levels and resting heart rate. The lipoprotein profile of swine and humans is also similar, and low density lipoprotein is the major cholesterol transporting lipoprotein in both species. Several studies in swine report conflicting results on the effect of exercise-training on lipoprotein profile and atherosclerotic lesion appearance. This may result from differences in total exercise time between the studies. With sufficient total exercise, atherosclerosis was reduced and high density lipoprotein cholesterol levels were increased. Exercise may also play a role in reducing obesity, a risk factor for cardiovascular disease, by enhancing lipid mobilization from adipocytes. Recent research suggests that swine adipocyte sensitivity to adenosine, a locally-produced antilipolytic agent, is reduced after exercise treatment. Cellular mechanisms responsible for this metabolic change include a reduction in adenosine A1 receptor number. Current studies are examining the transport of extracellular cyclic AMP from adipocytes and its role as a potential adenosine precursor. PMID- 9372478 TI - Effects of physical activity and diet on lipoprotein(a). AB - Lipoprotein(a) [Lp(a)] represents a class of lipoproteins with some structural similarity to low density lipoprotein (LDL), but containing a unique apoprotein, apoprotein(a). First reported in 1963, Lp(a) is now considered to have an independent role in the development of atherosclerotic lesions. The level of Lp(a) in the blood is under strong genetic influence and does not appear to be alterable by lifestyle factors known to influence other lipoproteins. Regular moderate exercise has been shown to favorably alter other lipoproteins, and recent attention has focused on whether Lp(a) level can be influenced by physical activity. Current data from cross-sectional and intervention studies show little effect of moderate exercise on serum Lp(a) concentration. One possible exception may be an elevation of serum Lp(a) concentration in adult endurance and power athletes who exercise intensely on a daily basis. However, not all studies have taken into account possible racial or ethnic differences in Lp(a) concentrations and the skewed distribution observed within most populations. Standard dietary intervention such as a low fat diet recommended for weight loss and control of other blood lipids has little effect on serum Lp(a) level. At present, serum Lp(a) concentration does not appear to be significantly altered by realistic dietary changes and moderate physical activity as recommended for health. The synergistic effect on cardiovascular disease risk when both LDL-cholesterol and Lp(a) are elevated highlight the importance of attending to those risk factors that can be modified by exercise and other lifestyle changes. PMID- 9372480 TI - Muscle-specific creatine kinase gene polymorphisms in elite endurance athletes and sedentary controls. AB - The purpose of this study was to investigate the association between elite endurance athlete (EEA) status and two restriction fragment length polymorphisms (RFLPs) at the muscle-specific creatine kinase (CKMM) gene locus. Genomic DNA was extracted from white blood cells or lymphoblastoid cell lines of 124 unrelated Caucasian male EEA (VO2max > 73 mL.kg-1.min-1) and 115 unrelated Caucasian sedentary male controls (SCON). The genetic polymorphism at the CKMM locus was detected by the polymerase chain reaction and DNA digestion with the NcoI and TaqI restriction endonucleases. The allelic frequencies for the NcoI and TaqI RFLPs were not different (P > 0.05) between EEA and SCON subjects. The three expected genotypes for CKMM-NcoI (1170/1170 bp, 1170/985 + 185 bp, and 985 + 185/985 + 185 bp) and CKMM-TaqI (1170/1170 bp, 1170/1020 + 150 bp, and 1020 + 50/1020 + 150 bp) were observed in the EEA and SCON groups. These genotype frequencies were in Hardy-Weinberg equilibrium, but they were not significantly (P > 0.05) different between the EEA and SCON. A strong (P < 0.001) linkage disequilibrium was detected among the NcoI and TaqI RFLPs in both EEA and SCON. These findings indicate that the skeletal muscle CK-NcoI and CK-TaqI gene polymorphisms are not associated with the elite endurance athlete status. PMID- 9372482 TI - Time course of enhanced endothelium-mediated dilation in aorta of trained rats. AB - Previous work has demonstrated that 10 wk of exercise training enhances the responsiveness of rat abdominal aortas to acetylcholine (ACh), an endothelium dependent vasodilator. The purpose of this study was to determine the time course for this training-induced adaptation of vascular endothelium. Additionally, the contribution of the cyclooxygenase and nitric oxide synthase mechanisms to the enhanced endothelium-mediated relaxation were examined. Male rats were divided into sedentary (SED) and exercise groups. Exercised animals were further subdivided into postexercise (POST-EX), 1 DAY, 1 WK, 2 WK, 4 WK and 10 WK groups. Exercise consisted of treadmill running at 30 m.min-1 (15 degrees incline) for 1 h.d-1 (5 d.wk-1 for the 1 WK, 2 WK, 4 WK, and 10 WK groups). Maximal vasodilator responses induced by 10(-4) M ACh (10(-7) M norepinephrine preconstriction) were determined on abdominal aortic rings in vitro immediately after a single exercise bout in POST-EX rats and 24 h after a single bout of exercise in 1 DAY animals. Maximal 10(-4) M ACh-induced dilation of aortas from 1 WK, 2 WK, 4 WK, and 10 WK animals was determined 24 h after the last exercise bout. Soleus muscle citrate synthase activity was greater in 2 WK (31 +/- 1 mumol.min-1.g wet wt-1), 4 WK (34 +/- 2), and 10 WK (36 +/- 1 mumol.min-1.g wet wt-1) rats than in SED (27 +/- 1 mumol.min-1.g wet wt.-1) animals. Maximal ACh-induced relaxation was greater in aorta from 4 WK (72 +/- 2%) and 10 WK (79 +/- 1%) rats than SED (61 +/- 2%) rats. ACh-mediated dilatory responses remained enhanced in the presence of the cyclooxygenase blocker indomethacin (10(-5) M), but were abolished by the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (300 microM). In addition, the expression of endothelial nitric oxide synthase (ecNOS) protein in aortas from 4 WK (P = 0.057) and 10 WK (P < 0.05) rats was greater than in aortas from SED animals. These data indicate that the enhanced endothelium-dependent, ACh-mediated dilation of the rat aorta is present by 4 wk of endurance exercise training. This adaptation appears to be mediated primarily through the nitric oxide synthase pathway and is associated with an increased expression of ecNOS. PMID- 9372481 TI - Absence of linkage between VO2max and its response to training with markers spanning chromosome 22. AB - An extensive search for linkage between DNA markers and the response of VO2max to training has recently been launched in the HERITAGE Family Study. This is the first report on a genome-wide search strategy to locate chromosomal regions and positional candidate genes for cardiorespiratory endurance phenotypes. Linkage between seven markers spanning chromosome 22 spaced approximately 10 cM apart (D22S264, D22S274, D22S301, D22S304, D22S421, IL2RB, and PDGFB) and VO2max at baseline, as well as its response to endurance exercise training, was examined using the sib-pair linkage method. Markers were genotyped in at least 210 sib pairs derived from 128 adult brothers (25 +/- 6 yr; mean +/- SD) and 138 sisters (24 +/- 6 yr) from 86 Caucasian families. VO2max, maximal heart rate, and maximal oxygen pulse were measured during stationary cycle tests before and after a standardized 20-wk endurance training program. On average, the initial VO2max was 2654 +/- 767 mL.min-1 while training increased VO2max significantly by 430 +/- 239 mL.min-1 or 16% (P < 0.0001). The VO2max response was adjusted for age and initial VO2max. No evidence of linkage was found between any of these markers on chromosome 22 and VO2max or its trainability. PMID- 9372483 TI - Resistance exercise prevents plantar flexor deconditioning during bed rest. AB - Because resistance exercise (REX) and unloading induce opposing neuromuscular adaptations, we tested the efficacy of REX against the effects of 14 d of bed rest unloading (BRU) on the plantar flexor muscle group. Sixteen men were randomly assigned to no exercise (NOE, N = 8) or REX (N = 8). REX performed 5 sets x 6-10 repetitions to failure of constant resistance concentric/eccentric plantar flexion every other day during BRU. One-repetition maximum (1RM) strength was tested on the training device. The angle-specific torque-velocity relationship across 5 velocities (0, 0.52, 1.05, 1.75, and 2.97 rad.s-1) and the full range-of-motion power-velocity relationship were assessed on a dynamometer. Torque-position analyses identified strength changes at shortened, neutral, and stretched muscle lengths. Concentric and eccentric contractile work were measured across ten repetitions at 1.05 rad.s-1. Maximal neural activation was measured by surface electromyography (EMG). 1RM decreased 9% in NOE and improved 11% in REX (P < 0.05). Concentric (0.52 and 1.05 rad.s-1), eccentric (0.52 and 2.97 rad.s 1), and isometric angle-specific torques decreased (P < 0.05) in NOE, averaging 18%, 17%, and 13%, respectively. Power dropped (P < 0.05) in NOE at three eccentric (21%) and two concentric (14%) velocities. REX protected angle-specific torque and average power at all velocities. Concentric and eccentric strength decreased at stretched (16%) and neutral (17%) muscle lengths (P < 0.05) in NOE while REX maintained or improved strength at all joint positions. Concentric (15%) and eccentric (11%) contractile work fell in NOE (P < 0.05) but not in REX. Maximal plantar flexor EMG did not change in either group. In summary, constant resistance concentric/eccentric REX completely prevented plantar flexor performance deconditioning induced by BRU. The reported benefits of REX should prove useful in prescribing exercise for astronauts in microgravity and for patients susceptible to functional decline during bed- or chair-bound hospital stays. PMID- 9372484 TI - Effect of alterations in blood volume on cardiac function during maximal exercise. AB - Recently, we proposed that the higher stroke volume (SV) and cardiac output (Q) of endurance-trained (ETR) versus untrained (UTR) individuals are attributable primarily to the enhanced diastolic filling of ETR consequent to a larger blood volume (BV). To test this hypothesis, we examined the effects of manipulating BV on the cardiac function of six ETR and six UTR males. Both groups were examined in the control BV condition (BVctl), then ETR were examined immediately following a 500 mL reduction in BV (BVred) and UTR were examined immediately following a 500 mL expansion of BV (BVexp). In BVctl, compared with UTR, ETR had significantly greater BV (16%), maximal diastolic filling rate (47.4%), maximal ventricular emptying rate (24.6%), SVmax (31.6%), Qmax (29%) and VO2max (54.5%). Following BVexp in UTR, there were immediate significant increases in maximal diastolic filling rate (22.5%), SVmax (9.1%), Qmax (8.9%), and VO2max (12.7%). Following BVred in ETR there were immediate significant decreases in maximal diastolic filling rate (27%), SVmax (14.3%), Qmax (14.7%), and VO2max (7.0%). Maximal systolic emptying rate did not change significantly following BVred or BVexp. We conclude that changes in SV and Q consequent to alterations in BV are attributable primarily to changes in diastolic function, and the majority of the higher diastolic filling rate of ETR is due to their larger BV. PMID- 9372485 TI - Water budget during ultra-endurance exercise. AB - We examined water gains and water losses in a group of athletes after an ultra endurance event. Thirteen male triathletes competed in a triathlon consisting of 21 km canoeing, 97 km cycling, and 42 km running. Water loss determinations included sweat rate (940 +/- 163 g.h-1), urine output (41 +/- 38 g.h-1), and respiratory water loss (88 +/- 10 g.h-1). Water gain measurements included water intake (737 +/- 137 g.h-1) and the water content of the food intake (10 +/- 7 g.h 1), and we estimated the water of metabolism for carbohydrate (49 +/- 5 g.h-1) and fat (41 +/- 5 g.h-1) and the water released after glycogen utilization (104 +/- 64 g.h-1). Total water gain averaged 940 +/- 160 g.h-1, while the total water loss averaged 1069 +/- 163 g.h-1. Body weight changed from 69.87 +/- 7.14 kg before the race to 66.65 +/- 6.75 kg after the race (-4.61 +/- 2.94%). The sum of the exogenous water gains and the endogenous water gains (940 g.h-1) replaced almost 90% of the total water loss (1069 g.h-1). The difference (1334 g) represented a loss of about 1.9% of the initial body mass (69.87 kg). The exogenous water gains alone (747 g.h-1) replaced about 70% of the total water loss, and the difference represented a loss of over 4% of the initial body mass. Because of the nature of the endogenous sources of water gain, the total amount of water gain almost replaces the total amount of water loss (difference approximately 12%) even in the presence of a reduction in body mass (> 4%). PMID- 9372487 TI - Technique and energy losses in front crawl swimming. AB - Forces in human swimming consist of two components, a drag force and a lift force. The lift force is assumed to be beneficial because of the relative small energy loss to the water. This energy loss can be quantified by determining the propelling efficiency, ep (defined as the ratio of the useful power to the total power output). The first purpose of this study was to investigate whether high values of propelling efficiency can be explained by a relatively high contribution of lift and/or a favorable direction of the generated force in front crawl swimming. Propelling efficiency was estimated using two methods, one based on a physiological approach (epp) by measuring oxygen consumption and one based on a kinematic approach (epk) by calculating forces generated by hands and forearm and power components, from a three-dimensional analysis. The second purpose of this study was to compare epp and epk. The contribution of lift to the total force as well as the direction of the force cannot explain the values of epp. The values of epp and epk did not correlate significantly. In swimming propulsion some processes play a role which cannot be explained at this moment. One of these processes might be the generation of vortices. PMID- 9372486 TI - Autonomic differences between athletes and nonathletes: spectral analysis approach. AB - The purpose of this study was to assess the adaptive effects of endurance training on autonomic function in athletes with spectral analysis of cardiovascular variability signals. Continuous ECG, arterial blood pressure (ABP), and respiratory signals were recorded from 15 athletes (VO2max > 55 mL.min 1.kg-1) and 15 nonathletes (VO2max < 45 mL.min-1.kg-1) during 10 min at sitting position. Autonomic function was assessed by low frequency power (LF power: 0.06 0.14 Hz) and high frequency power (HF power: the region of the respiratory frequency based on respiratory spectrum) obtained from the autospectra of RR interval, systolic arterial pressure (SAP), and diastolic arterial pressure (DAP) variability signals. The spontaneous baroreflex sensitivity was evaluated by the moduli, BRSLF and BRSHF, of the transfer function between RR interval and SAP variability in LF and HF bands. The resting HR in athletes was significantly lower than that in nonathletes. The HF power, an index of parasympathetic activity, in RR interval spectra were significantly higher in athletes than in nonathletes. Meanwhile, the LF power (an indicator of sympathetic activities contributing to RR interval and of ABP variabilities) showed no significant difference between both groups, although that of athletes was slightly less than that of nonathletes. Also, BRSLF and BRSHF were not significantly different between athletes and nonathletes. These results indicate that endurance training results in the enhanced vagal activities in athletes, which may contribute in part to the resting bradycardia. PMID- 9372488 TI - Effect of training on repeatability of cardiopulmonary exercise performance in normal men and women. AB - The effect of gender and training on repeatability of cardiopulmonary exercise performance has not been well defined. Therefore, we performed two bicycle exercise tests 1 wk apart in each of two groups: In 19 normal subjects (age 24 to 64 yr, 10 females), with a mean maximal oxygen uptake (VO2max) of 42 mL.kg-1.min 1, who had been in an ongoing training program including bicycle exercise, and in 19 untrained volunteers (23 to 54 yr, 11 females) with a mean VO2max of 36 mL.kg 1.min-1 (P < 0.05). Mean differences in physiologic variables measured during tests 1 and 2 were calculated. Repeatability coefficients were defined as 2 SD in percent of the means. In untrained subjects mean (+/- SD) maximal heart rate decreased by 4 +/- 5 beats.min-1 from the first to the second test (P < 0.05). VO2max and maximal work rate (Wmax) remained unchanged. No significant changes in these or other variables occurred in trained subjects. Repeatability coefficients for VO2max were 8 and 13% in trained and untrained subjects, respectively (P = NS). For Wmax the repeatability coefficient in untrained (11%) exceeded that in trained subjects (4%, P < 0.05). Repeatability coefficients did not differ among males and females. Our study provides normal values for repeatability of various parameters assessed during exercise testing and demonstrates that interpretation of performance during repeated tests has to account for training of the subjects. PMID- 9372489 TI - Inertial-load method determines maximal cycling power in a single exercise bout. AB - A cycle ergometer was modified to measure power (P) with resistance provided solely by the moment of inertia (I) of the flywheel. P was calculated as the product of I, angular velocity (omega), and angular acceleration (alpha). Flywheel omega and alpha were determined by means of an optical sensor and a micro-controller based computer interface which measured time (+/- 1 microsecond) and allowed P to be calculated instantaneously (PI) every 3 degrees of pedal crank rotation or averaged over one complete revolution of the pedal cranks (PREV). Values for maximum P were identified from each bout (PI max and PREV max). Mechanical calibration of torque via a resistive strap proved this method to be both valid and accurate. Thirteen active male subjects performed four bouts of maximal acceleration lasting approximately 3-4 s with 2 min resting recovery. The mean coefficient of variation for PREV max was 3.3 +/- 0.6% and the intraclass correlation was 0.99. PREV max averaged 1317 +/- 66 W at 122 +/- 2 rpm, and PI max averaged 2137 +/- 101 W at 131 +/- 2 rpm. PREV max and PI max were highly correlated (r = 0.86 and r = 0.80 respectively, P < 0.002) with estimated lean thigh volume. Therefore, the inertial-load method provides a valid and reliable determination of cycling power in one short exercise bout. PMID- 9372490 TI - Comparison and cross-validation of cycle ergometry estimates of VO2max. AB - The purpose of this study was to examine the accuracy and quality of a series of cycle ergometry tests used to estimate maximal aerobic capacity (VO2max). One hundred nine males and 71 females participated in five tests: a maximal exercise test on the treadmill, three Air Force Cycle Ergometry Tests (AF1, AF2, AF3), and a Progressive cycle ergometry test (PROG). The VO2max value measured during the treadmill test was compared with the VO2max estimates from each ergometry test. The AF1, AF2, and AF3 results were used to determine reliability. The mean estimated VO2max for each, except the PROG, was significantly different (P < 0.05) from the measured VO2max. The AF1 and AF-avg tests underestimated VO2max by 8.0 and 6.5 mL.kg-1.min-1, respectively, values which were 17.3 and 14.9% lower than the measured VO2max. Correlation coefficients between estimated VO2max values and the measured VO2max ranged from 0.59 to 0.80 with SEE ranging from 1.8 to 2.2 mL.kg-1.min-1. The PROG had the greatest sensitivity (82.2%), while the AF2 had the greatest specificity (70.6%). Additionally, 23.4% of the VO2max estimates from the PROG were within +/- 5% of the measured VO2max compared with 9.9% for the average of the Air Force tests. The intraclass correlation coefficient for the three AF tests or the reliability for a single AF test was 0.26. In sum, the Air Force test provides an estimate of VO2max, and hence aerobic capacity, which is unreliable and underestimates the true VO2max by approximately 15%. PMID- 9372491 TI - Comparison of free range and graded exercise testing. AB - Previous studies with athletes have demonstrated greater physiologic responses during free range (FR) compared with graded (GXT) exercise testing. Since the sensitivity of clinical exercise testing depends upon the magnitude of physiologic responses, we sought to determine whether FR might provoke greater responses than GXT in nonathletic individuals and patients. Healthy, physically active nonathletes and clinically stable CHD patients (N = 12) performed GXT on cycle ergometer (15 W + 15 W.min-1) and FR (minimal time for 75 kJ task) on a cycle ergometer. A starting power output was recommended for FR, but the patients were free to pedal at their own rates. During FR, VO2max (36.5 +/- 10.1 vs 34.1 +/- 9.4 mL.min-1.kg-1), HRmax (156 +/- 25 vs 144 +/- 27 beats.min-1), double product (31.4 +/- 4.9 vs 29.1 +/- 5.9) and VEmax (111 +/- 26 vs 94 +/- 17 L.min 1) were all significantly greater than during cycle GXT. The mean peak power output during GXT (180 +/- 45 W) was not significantly different than the mean power output during FR (204 +/- 45 W). During FR, successive "0.5 mile laps" (approximately 12.5 kJ) were accomplished at power outputs of 217 +/- 45, 217 +/- 52, 192 +/- 60, 194 +/- 65, 199 +/- 63, and 207 +/- 63 W. No patient experienced angina or ECG changes during either FR or GXT. The patients uniformly reported that FR felt like "hurrying" in the real world. Some patients had to make large reductions in their power output in mid ride to allow recovery from a too aggressive start, much as they would in the real world. We conclude that FR exercise provides a clinically useful method of exercise testing that is not only more like real world exercise patterns but also provokes greater physiologic responses than are achievable during conventional GXT. PMID- 9372492 TI - Body composition by x-ray absorptiometry and bioelectrical impedance in female runners. AB - Body composition interests athletes since athletic performance is influenced by and dependent on the proportion and total amount of fat-free mass (FFM) and fat mass. The use of bioelectrical impedance (BIA) has increased recently since portable instruments make the measurements easy to execute and relatively inexpensive. The purpose of this study was to test the degree of relationship between FFM and fat mass calculated in elite female runners with 12 different BIA formulas reported in the literature and measured by dual-energy x-ray absorptiometry (DXA). The present study shows that body composition by BIA is valid in female runners. Prediction equations used to calculate FFM and fat mass must be appropriate for this population subgroup and validated against other methods, such as DXA and hydrodensitometry. Those formulas that performed well in the controls gave poor results in the female runner and vice versa. The below average fat mass noted in female runners suggests that prediction equations for untrained women with average fat mass are inappropriate. The formula by RJL Systems-2 for women: FFM = 5.091 + 0.6483.height2/resistance + 0.1996.weight gave best predictions of FFM in female runners. Further research is necessary to validate BIA prediction formulas in other athletes. PMID- 9372493 TI - Relationships between TriTrac-R3D vectors, heart rate, and self-report in obese children. AB - The TriTrac (Professional Products, Inc., Madison, WI) triaxial accelerometer and diary self report were compared with adjusted heart rates to evaluate 3 d of leisure-time activity in 35 8- to 12-yr-old obese children. Adjusted heart rates were calculated by subtracting preexercise resting heart rates from heart rates measured in the field. TriTrac and self-reported data were converted to multiples of resting metabolic rate (METs). Correlations between accelerometer METs and adjusted heart rates (r = 0.71) were significantly higher (P < 0.001) than correlations between adjusted heart rates and self-reported METs (r = 0.36) or accelerometer and self-reported METs (r = 0.38). Self-reported METs had higher mean standard errors in estimating heart rates (13.93 +/- 6.15 beats.min-1) than did accelerometer METs (10.94 +/- 5.62 beats.min-1; P < 0.001), were significantly greater than accelerometer METs (2.50 +/- 1.48 vs 1.80 +/- 1.48; P < 0.05) and systematically overestimated accelerometer METs. The anteroposterior vector accounted for 36%, and the vector magnitude score accounted for 34% of the variance in unadjusted heart rates. The mediolateral vector and vector magnitude score accounted for 69% of the variance in self-reported METs. The vertical vector did not account for variance in either unadjusted heart rates or self reported METs. It was concluded that the TriTrac yielded a better estimate of activity in obese children than self report. In addition, the vector magnitude composite score of the TriTrac accounted for significantly more variance in both self-reported activity and unadjusted heart rates as compared with the vertical directional vector of the TriTrac. PMID- 9372494 TI - Review of microscopic studies on the fetal and neonatal kidney. AB - The developing mammalian kidney has been studied by light microscopic, electron microscopic, immunohistochemical, and autoradiographic techniques. The microscopic studies have been conducted on in vivo samples and in vitro samples. The cellular biology and molecular biology of the developmental steps have been clarified, but more investigations are needed. Information has also been collected concerning the influence of the environment on the microscopic development of the kidney. PMID- 9372495 TI - Renin-angiotensin system genes in kidney development. AB - The renin-angiotensin system (RAS) plays a key role in cardiovascular homeostasis through the interactions of angiotensin II with its receptors. All components of the RAS are developmentally regulated in the kidney. The functions of the system in the maturing kidney overlap those of the adult, but higher levels of expression and novel locations of expression in the fetus suggest that the RAS has alternate functions as well. Increasing evidence suggests that the RAS may regulate renal growth and development by initiating a complex cascade of events, involving growth factors and proto-oncogenes and other unidentified factors. These same cascades may also be important in renal disease states. Recent advances in the field of molecular and cell biology are providing new tools and strategies to elucidate the intimate mechanism whereby the RAS regulates growth processes and disease states. PMID- 9372496 TI - Ontogeny of the intrarenal kallikrein-kinin system: proposed role in renal development. AB - The kallikrein-kinin system (KKS) plays an important role in the regulation of renal function. Endogenous kinins modulate renal microvascular resistance, medullary blood flow, and distal nephron sodium and water reabsorption. All the components of the KKS, including tissue kallikrein, kininogen, kininase II, and kinin receptors are expressed within the kidney, establishing a paracrine system capable of controlling local nephron functions. In this review, data will be presented demonstrating that the developing kidney expresses an endogenous, functionally active KKS. Molecular studies have shown that gene expression of the renal KKS in the rat is activated postnatally, and that the intrarenal distribution of KKS components is subject to developmental control. Furthermore, the developmental expression of KKS appears to be regulated primarily at the transcriptional level. Ontogenetic studies have also revealed that the bradykinin B-2 receptor gene is overexpressed in the developing rat kidney. As kinins are potent vasoactive and growth-promoting factors, it is proposed that endogenous kinins mediate developmental renal growth and differentiation, and modulate the maturational changes which occur in renal hemodynamics. PMID- 9372497 TI - Morphogenesis of the glomerular filter: the synchronous assembly and maturation of two distinct extracellular matrices. AB - The morphogenesis of the glomerular filtration apparatus during pre- and postnatal development in the rodent involves the coordinated assembly of two closely apposed but morphologically different extracellular matrices, the glomerular capillary basement membrane and the mesangial matrix. The cellular origin of these matrices is known to be distinct and complex; however, the mechanisms by which these matrices are assembled during morphogenesis are not entirely understood. It has been shown that in the earliest stages of glomerular morphogenesis the nascent glomerular basement membrane exists as a four-layered structure, the product of both the visceral epithelium and capillary endothelium. During the latter stages of glomerular development, the quadrilaminar structure becomes a trilaminar basement membrane, the event thought to occur by fusion of closely apposed basement membrane layers. In subsequent stages of maturation and throughout the life of the animal, the visceral epithelial cells, which line the periphery of the glomerular capillary, are the primary source of newly synthesized basement membrane material. The mesangial matrix, which lacks the specific organization of a basement membrane, first occurs in the developing glomerulus as a diffuse matrix central to the developing glomerular capillaries. During glomerular maturation the mesangial matrix undergoes a compaction/arborization coincident with the ramification of the vascular histoarchitecture of the glomerular tuft. Recent advances in the cell biology of basement membrane now demonstrate that there is a divergence in isoforms of the molecules that comprise the glomerular capillary basement membrane and mesangial matrices during development, possibly coincidental with functional specialization during the process of glomerular maturation. PMID- 9372498 TI - Development of the kidney vasculature. AB - Renal vascularization and nephrogenesis occur simultaneously following a tightly regulated developmental program influenced by growth factors, extracellular matrix components and cell membrane receptors. Both processes of angiogenesis and vasculogenesis probably participate in the formation of renal vessels. The origin and fate of the various renal vascular cells and the molecular mechanisms that initiate and guide intrarenal vascularization are fundamental questions that remain to be answered. PMID- 9372500 TI - North American opossum Didelphis virginiana as a fetal nephrotoxicity model: histologic and ultrastructural assessment of uranyl nitrate (UN)-induced damage. AB - We have used our opossum model of fetal nephrotoxicity to investigate uranyl nitrate-induced morphologic changes in the developing kidney. The present study establishes a renal dose response curve for the uranyl nitrate (UN). We find that pups treated with nonlethal doses of UN do not demonstrate growth retardation compared to saline-treated controls. The kidneys of UN-treated pups are heavier than the control animals, an effect less apparent the longer the pups are followed. A low dose of 60 mg/kg of UN administered to small pups causes slight histologic derangement but nevertheless more change than the same dose administered to larger more mature pups. Using a dose of 100 mg/kg of UN that effectively causes nonfatal renal disruption, we examined the kidneys from 4 to 42 days following injection. We find that tubular dilation and epithelial necrosis starts soon after treatment (day 4) and reaches its maximum during the second and third week (11 and 22 days). Architectural restoration appears complete by the end of the third week. By electron microscopy, UN induces sequential structural damage with loss of proximal tubule brush border, epithelial necrosis with intact basement membranes and regeneration at 4, 11, and 22 days. Residual tubular mitochondrial damage is present at 42 days in spite of histologically normal tubules. No apparent lesions are seen in glomeruli. Fibroblastic interstitial proliferation in UN-treated kidneys at 11 days is not followed by appreciable fibrosis when assessed at 22 and 42 days. As the structural changes caused by 100 mg/ml UN administration in fetal opossum kidneys are reversible, this is a useful model to study the molecular mediators responsible for this form of renal damage and repair. PMID- 9372499 TI - Diverse aspects of metanephric development. AB - Mammalian nephrogenesis constitutes a series of complex developmental processes in which there is a differentiation and rapid proliferation of pluripotent cells leading to the formation of a defined sculpted tissue mass, and this is followed by a continuum of cell replication and terminal differentiation. Metanephrogenesis ensues with the intercalation of epithelial ureteric bud into loosely organized metanephric mesenchyme. Such an interaction is reciprocal, such that the intercalating ureteric bud induces the conversion of metanephric mesenchyme into an epithelial phenotype, while the mesenchyme stimulates the iterations of the ureteric bud. The induced mesenchyme then undergoes a series of developmental stages to form a mature glomerulus and tubular segments of the kidney. Coincidental with the formation of these nephric elements, the developing kidney is vascularized by the process of vasculogenesis and angiogenesis. Thus, the process of metanephric development is quite complex, and it involves a diverse group of molecules who's biological activities are inter-linked with one another and they regulate, in a concerted manner, the differentiation and maturation of the mammalian kidney. This diverse group of molecules include extracellular matrix (ECM) proteins and their receptors, ECM-degrading enzymes and their inhibitors, growth factors and their receptors, proto-oncogenes and transcription factors. A large body of literature data are available, which suggest a critical role of these molecules in metanephric development, and this review summarizes the recent developments that relate to metanephrogenesis. PMID- 9372502 TI - Chromatin pattern by variogram analysis. AB - Many cytological processes such as cell proliferation, differentiation, transformation, apoptosis, etc., are accompanied by specific chromatin changes, usually identified on the basis of the relative content of euchromatin and heterochromatin. In order to achieve a quantitative, non-subjective evaluation of the chromatin pattern, two different approaches may be undertaken, one consisting in the analysis of the several morphological features of chromatin grains (size, shape, density, arrangement, and distribution), and the second consisting in the analysis of the chromatin globally considered as a coherent texture. Although the second approach appears to be simpler and more suitable, methods of texture analysis--including those specifically designed for the analysis of the chromatin pattern--are rarely applied due mainly to the unsuitability of sampling procedures and the excessive crypticism of results. As an alternative to traditional texture analysis, we suggest a method supported by a sound mathematical theory and approximately 30 years of applications in the field of geostatistics. The method, called variogram, analyzes the intrinsic structure of data sampled at different distance intervals and directions, and outputs easily understandable results. Recently, variogram analysis has successfully been exported from geostatistics to other fields (for example, ecology and epidemiology) that make use of spatially referenced variables. Based on the fact that pixels represent a perfect array of data ordered at regular distance intervals and directions, the variogram can be adopted to explore nuclear images and recognize chromatin patterns. Variograms of different nuclei can be summarized by multivariate methods without the need of previous standardization of data. This allows comparison and discrimination of chromatin patterns from mixed cell populations. Preliminary data obtained from young neurons undergoing massive apoptosis reveal a self-consistent map of nuclear changes correlated to the degenerative process. PMID- 9372501 TI - Reevaluation of the effect of lysoyzme on Escherichia coli employing ultrarapid freezing followed by cryoelectronmicroscopy or freeze substitution. AB - Lysozyme is able to lyse Gram-positive bacteria acting as muramidase on the peptidoglycan polymer. Gram-negative bacteria in vitro are not lysed by lysozyme. It was assumed that the peptido-glycan is protected by the outer membrane and thus that Gram-negative bacteria are not affected by lysozyme without the aid of other factors such as EDTA or complement which enable lysozyme to penetrate the outer membrane. Accidentally, Pellegrini et al. [(1992) J. Appl. Bacteriol., 72:180-187] found that lysozyme per se is able to kill some Gram-negative bacteria. On the basis of morphological and immunocytochemical findings obtained from chemically fixed bacteria, it was concluded that lysozyme does not lyse Gram negative bacteria but affects the cytoplasm of for example, Escherichia coli, leading to its disintegration, whilst the membranes do not break down. In an attempt to clarify the action of lysozyme on E. coli, we employed cryotechniques including ultrarapid freezing, cryomicroscopy and freeze substitution, and immunolabeling. Bacteria that were immediately frozen after exposure to lysozyme remained morphologically intact. Individual bacteria plated on agar after exposure to lysozyme were mostly intact when frozen within a few seconds. However, inner and outer membranes of 80% of the bacteria were disrupted, whereas the cytoplasm of only a few bacteria showed signs of disintegration when bacteria were frozen with a delay of only 5 min of plating onto pure agar or agar containing growth medium. After a period of time of 15 min between plating onto agar and freezing, about 97% of the bacteria showed changes of disintegration of various extent. Immunolabeling showed that lysozyme binds to the outer cell membrane and may penetrate the membrane, reaching the periplasmic space and possibly the inner cell membrane. The ultrastructural findings and the results of antibacterial assays suggest that lysozyme is bactericidal for E. coli but is not able to induce disintegration. Disintegration is accomplished by changes of the environment starting at the cell membranes. The mechanism by which lysozyme penetrates the membrane, the way it acts to be bactericidal, and the way disintegration is initiated remain to be clarified. PMID- 9372503 TI - MRI measures and their relations with clinical disability in relapsing-remitting and secondary progressive multiple sclerosis. AB - To further evaluate the relationship between clinical disability and Magnetic Resonance Imaging (MRI) lesion burden, we examined 85 patients with clinically definite multiple sclerosis (54 relapsing-remitting and 31 secondary progressive). This cross-sectional study reports on the correlations between total and infratentorial lesion volume on both T1 and T2 weighted images, and overall physical disability measured by Expanded Disability Status Scale, ambulation index and individual functional systems. Assessment of the hypointense lesion load on T1 weighted images rather than the hyperintense lesion load on T2 weighted images at brain MRI was shown to be useful for differentiating relapsing remitting from secondary progressive Multiple Sclerosis. A weak relationship between disability and total lesion volume on both T1 and T2 weighted images was found in relapsing-remitting Multiple Sclerosis. In secondary progressive Multiple Sclerosis, infratentorial lesion volume on T2 weighted images represents the only marker of disability. Finally, the presence of cerebellar, brainstem and mental impairment was significantly associated to a greater total lesion volume on MRI, while no relationship was found with other functional systems. PMID- 9372504 TI - Inter-rater variability in reporting enhancing lesions present on standard and triple dose gadolinium scans of patients with multiple sclerosis. AB - In this study we evaluated and compared the inter-rater variabilities in detecting enhancing lesions in patients with MS after injection of a standard dose (s.d.) and a triple dose (TD) of gadolinium (Gd). Enhanced magnetic resonance imaging (MRI) were obtained in 15 patients, consisting of T1-weighted images 5 to 7 min after the injection of the s.d. (0.1 mmol/kg) of Gd and, after an interval of 6 to 24 h, 5 to 7 min after the injection of the TD (0.3 mmol/kg). An additional scan 1 h after the TD injection (delayed scanning-DS) was obtained in 11 patients. The scans were independently evaluated in a random order by four observers. Lesions were counted and scored according to size and location. The level of inter-observer observer concordance was very high for reporting the total numbers of enhancing lesions, their sizes and sites for the three experimental conditions. No significant differences were found in inter-observer variability in reporting the total number of enhancing lesions and their location in different brain sites in the three conditions. Our data indicate that the gain in sensitivity in detecting enhancing lesions in MS with the TD is not counteracted by a loss in reproducibility. This is important in planning clinical trials in which the number of enhancing lesions is used as a measure of outcome. PMID- 9372505 TI - 1H MRSI of normal appearing white matter in multiple sclerosis. AB - The primary goal of this study was to determine if differences in proton magnetic resonance spectroscopy signals exist between normal appearing white matter (NAWM) of multiple sclerosis (MS) patients and white matter of control subjects. Water suppressed proton magnetic resonance spectroscopic imaging was used to determine the signal intensities of N-acetylated moieties (NA, predominantly N acetylaspartate (NAA) the putative neuronal marker), creatine and phosphocreatine (Cr), and cholines (Ch) in 19 MS patients (15 relapsing-remitting and four secondary progressive) and 19 age matched control subjects. NA/Cr was significantly reduced (P < 0.001) in MS NAWM (1.8 +/- 0.2; x +/- s.d.) distant from MRI detected lesion areas compared to white matter of control subjects (2.1 +/- 0.2). This reduction was due to an increase in Cr from 0.39 +/- 0.04 (arbitrary units) in controls to 0.45 +/- 0.05 in MS patients. There was no significant change in NA or Ch in MS NAWM compared to controls. NA/Cr, distant from MRI lesion, was negatively correlated with total brain lesion volume as measured from T2-weighted MRI. We interpret the reduced NA/Cr in MS NAWM to indicate diffuse microscopic disease. PMID- 9372506 TI - T cell-T cell activation in multiple sclerosis. AB - Activated T cells are able to stimulate proliferation in resting T cells through an antigen non-specific mechanism. The in vivo usefulness of this T cell-T cell activation is unclear, but it may serve to amplify immune responses. T cell-T cell activation could be involved in the well-documented occurrence of multiple sclerosis (MS) exacerbations following viral infections. Excessive activation via this pathway could also be a factor in the etiology of MS. We tested the hypothesis that excessive T cell-T cell activation occurs in MS patients using in vitro proliferation assays comparing T cells from MS patients to T cells from controls. When tested as responder cells, T cells from MS patients proliferated slightly less after stimulation with previously activated cells than T cells from controls. When tested as stimulator cells, activated cells from MS patients stimulated slightly more non-specific proliferation than activated cells from controls. Neither of these differences were statistically significant. We conclude that T cell proliferation in response to activated T cells is similar in MS and controls. PMID- 9372507 TI - Influenza virus vaccination of patients with multiple sclerosis. AB - Prior to vaccination with a trivalent influenza vaccine (AT/Texas, AB/Beijing, and BP/Panama), sera from 19 MS patients had a significantly higher mean level of antibody than 9 normal subjects to AT strain of influenza, but not to AB or BP strains. After Flu vaccination, the mean anti-AT and anti-AB antibody titers significantly increased 4-fold in 11 MS patients and 9 normal subjects. The ratio of MS responders (6/11), however, was lower than normal (8/9). The mean PBL proliferative response to the Flu antigens increased after vaccination significantly more in MS patients than in normal subjects, and increased in 9 of 11 MS patients and 3 of 9 normal subjects. Although MS patients responded to Flu antigens with higher antibody levels and proliferative responses of PBL, than normal subjects, a clinical protective effect of the vaccine against Flu was not clearly demonstrated in these patients, and vaccination did not cause or protect against exacerbation of MS. PMID- 9372508 TI - Treatment of multiple sclerosis with high-dose corticosteroids may prolong the prothrombin time to dangerous levels in patients taking warfarin. AB - Two patients who were taking warfarin experienced significant prolongations of the prothrombin time (protime) after treatment with high-dose corticosteroids for rapid progression of MS. This complication of therapy is potentially life threatening. PMID- 9372509 TI - Open label gabapentin treatment for pain in multiple sclerosis. AB - Pain is a frequent and distressing complaint in patients with multiple sclerosis (MS) and may present a difficult therapeutic problem. Conventional therapy is moderately effective and includes, among others, a variety of anticonvulsant medications. Gabapentin (Neurontin) is a new generation antiepileptic drug which appears to be advantageous in treatment of intractable pain of reflex sympathetic dystrophy. This study investigates the benefits of open-label treatment with gabapentin for pain control in 25 patients with MS. Excellent to moderate pain relief was obtained in a substantial number of patients. Throbbing pains and needles, and cramping pains responded best, and dull aching pains responded least to the medication. There was no significant change in distribution and type of pain as a result of this treatment. Mild to moderate side effects were observed. Cautious escalation of the dose of gabapentin is advisable in MS patients. Further clinical trials with larger patient groups are recommended. PMID- 9372510 TI - Depression, coping and level of neurological impairment in multiple sclerosis. AB - This study examined the relationship between coping and depression in multiple sclerosis patients, and how that relationship varies at different levels of physical impairment. One-hundred and one patients with clinically definite MS were assessed using the Kurtzke Expanded Disability Status Scale (EDSS), the Ways of Coping Inventory (WCI) with three sub-scales developed by Wineman et al, and the Beck Depression Inventory (BDI). Depression was significantly higher at more advanced levels of neurologic impairment than at lower levels. Escape-Avoidance and Emotional Respite were positively related to level of depression. Planful Problem-Solving and Cognitive Reframing were negatively related to depression. An interaction between coping, depression, and level of neurologic impairment was observed in which Planful Problem-Solving and Cognitive Reframing were more strongly related to depression at higher levels of impairment. The interaction effect for Escape-Avoidance and Emotional Respite with depression and level of impairment did not reach significance. It was concluded that there is a significant interaction between level of neurologic impairment, coping behaviors, and depression in patients with MS. PMID- 9372511 TI - CD4+ T lymphocytes contribute to protective immunity induced in sheep and goats by Haemonchus contortus gut antigens. AB - Immunization with parasite antigens derived from the gut of adult Haemonchus contortus induces significant levels of protection against the parasite in sheep and goats. However, the mechanisms of immunity involved in this protection are not clear. Here, we investigate the requirement for CD4+ T lymphocytes in gut antigen-induced immunity against H. contortus. Gut antigen immunized animals were depleted (> 98%) of their CD4+ T lymphocytes in peripheral blood by intravenous injection of an anti-CD4 MoAb. Depletion in peripheral blood persisted for at least eight days, after which there was gradual recovery of CD4+ T lymphocytes. Serum antibody levels in gut antigen-immunized animals correlated significantly with worm parameters, suggesting a contribution by antibody to the immunity observed. By covariate analysis, using ELISA OD as the covariate, CD4+ T lymphocyte depletion was shown to partially abrogate immunity induced by gut antigen immunization, against challenge infection with H. contortus. The greatest effect of CD4+ T lymphocyte depletion was observed at 14 days post-infection with differences between CD4+ T lymphocyte depleted and intact animals less apparent between days 21 and 25. Collectively, our data indicate that CD4+ T lymphocytes contribute to immunity induced by gut antigens. Our results also suggest that antibody works synergistically with CD4+ T lymphocytes to confer this immunity. PMID- 9372512 TI - Protective immunity induced by vaccination with two Haemonchus contortus excretory secretory proteins in sheep. AB - Two excretory secretory (ES) antigens of adult Haemonchus contortus with molecular weights of 15 and 24 kDa, respectively, were evaluated as protective immunogen against haemonchosis. Sheep were vaccinated three times and subsequently challenged with 20,000 infective larvae. Vaccination induced significant reduction (> 70%) in mean faecal egg counts and abomasal worm burden compared to the non-vaccinated control group or adjuvant control group. Vaccination induced ES-specific antibodies and stimulated infiltration of mast cells in the abomasal tissue. PMID- 9372513 TI - Long-term survival of 'damaged' Nippostrongylus brasiliensis adult worms in the testosterone-treated Indian soft-furred rat, Millardia meltada. AB - When testosterone-treated female Millardia meltada were infected with Nippostrongylus brasiliensis, adult worms persisted for over seven weeks. The kinetics of faecal egg counts showed a biphasic pattern having a transient decline at around two weeks post infection (p.i.). Thus the status of N. brasiliensis adult worms surviving in the small intestines of testosterone treated M. meltada was examined. The fecundity and maturity of eggs in the uteri of female adult worms were examined at one, two, three and seven weeks p.i. Both the fecundity and maturity of eggs transiently decreased at two and three weeks p.i. and then completely recovered by seven weeks. Adoptive transfer of N. brasiliensis adult worms into naive recipients can discriminate the status of worms. Those obtained from the stable phase of a primary infection ('normal' worm) can establish and survive in the recipients, whereas those obtained at the time of expulsion ('damaged' worm) are rapidly expelled. Therefore, 300 each of N. brasiliensis adult worms collected from the testosterone-treated female M. meltada at one, two and seven weeks p.i. were transferred intraduodenally into normal rats to determine their status. Those collected at one week p.i. persisted for eight days, indicating that they were still 'normal'. In contrast, worms collected at two and seven weeks p.i. were expelled within four days, indicating that they had already been 'damaged'. Moreover, when the 'damaged' worms obtained from rats were intraduodenally transferred into testosterone-treated female M. meltada, they were not expelled, suggesting that testosterone-treatment affected the final expulsive step, but not the damaging process, of the mucosal defence of M. meltada against N. brasiliensis adult worms. PMID- 9372514 TI - Nematode infection induces Th2 cell-associated immune responses in LEC mutant rats with helper T cell immunodeficiency. AB - Long-Evans Cinnamon (LEC) rats have maturational arrest of CD4+8- T cells from CD4+8+ cells in the thymus. Despite this, CD4+8- T cells are always present in peripheral lymphoid organs of LEC rats, suggesting that these CD4+8- T cells are generated by an uncommon pathway. We investigated the role of LEC rat peripheral CD4+8- T cells in Th2-associated responses to infection with the nematode Nippostrongylus brasiliensis. After infection, the numbers of CD4+8- TCR alpha beta + T cells significantly increased in mesenteric lymph nodes (MLN) and the spleen, while those in the thymus were still negligible. Infection also induced significant up-regulation of IL-4 gene expression in LEC rat MLN cells. Total serum IgE levels in LEC rats were markedly increased two weeks after infection. Mucosal mast cell responses in the gut and lungs of LEC rats were induced as prominently as in control Long-Evans Agouti (LEA) rats. Faecal egg count data indicated that LEC rats rejected nematodes faster than LEA rats. These results suggested that Th2-associated responses can be induced by nematode infection in LEC rats probably through the extrathymic recruitment and proliferation of CD4+8- TCR alpha beta + T cells. PMID- 9372515 TI - Non-specific binding of IgG1 to Heligmosomoides polygyrus: adult worm homogenate superantigen is a target for immunoglobulin-induced inhibition. AB - Previous evidence had indicated that selected antigens contained in H. polygyrus adult worm homogenate (AWH) could bind non-specifically to mouse IgG1. To determine whether H. polygyrus superantigen was one of these binding molecules, an inhibition assay was carried out using monoclonal antibodies (MoAb) to block the in vitro superantigen response. The results indicated that non-specific IgG1 binding could inhibit the cellular response to the superantigen. This assumption was tested using affinity chromatography to extract those antigens which bound non-specifically to mouse IgG1. Both the protein fraction which bound to the column and the unfractionated AWH demonstrated superantigen activity, as described previously. In contrast, the unbound fraction contained no superantigen activity. None of the tested fractions exhibited non-specific mitogen activity. These results indicate that the superantigen produced by H. polygyrus binds to host IgG1 of any specificity and this binding can inhibit further host recognition of this molecule. Additionally, it was demonstrated that an apparently similar superantigen is also contained in L4 homogenate, and is strongly represented in the excretory/secretory (E/S) proteins produced by both adult and L4 parasitic stages. Therefore, it is probable that H. polygyrus superantigen influences the host during both the L4 and adult stages of the life cycle. PMID- 9372516 TI - Evidence for direct interaction between mast cells and Leishmania parasites. AB - When stimulated through IgE-(or IgG-) immune complexes with parasite antigens, mast cells can release several cytokines, including IL-4, IL-6, IL-10, IL-12, Interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) that may influence the host response to Leishmania major in modulating lesion size and persistence during experimental infection in the mouse. Moreover, recent data demonstrated that mast cells are able to be antibody-independently activated by direct contact with bacteria, making them important elements in innate immunity. Given these data, we asked whether cell-parasite contact could directly induce mast cell mediator release and whether mast cells could be infected by L. major or L. infantum parasites. In this study, we showed that a pure homogeneous population of mouse bone marrow derived mast cells (BMMC) in contact with living L. major or L. infantum promastigotes, but not with attenuated parasites or soluble parasite antigens, released preformed mediators such as beta hexosaminidase and the preformed pool of TNF-alpha within minutes. Furthermore, direct cell-parasite contact induced TNF-alpha synthesis by mast cells within hours. Moreover, we demonstrated by in vitro co-culture experiments that metacyclic L. major or L. infantum promastigotes are directly infective for a significant proportion of BMMC and are transformed into intracellular amastigotes. Taken together, these data suggest that mast cell can participate in the first line of defence, i.e. innate immunity, during local cutaneous infection with Leishmania parasites. PMID- 9372517 TI - Phototesting for polymorphic light eruption (PLE) with consecutive UVA1/UVB irradiation. PMID- 9372518 TI - Role of viral infection in porphyria cutanea tarda. AB - HIV infection is associated with abnormal porphyrin metabolism. While HCV infection alone is thus far not associated with significant abnormal porphyrin levels, it does contribute to further elevation of porphyrin levels in patients already infected with HIV. These infections alone are not sufficient to induce the development of clinical porphyria. However, they render patients susceptible to having symptomatic porphyria upon exposure to other porphyrinogenic agents. PMID- 9372519 TI - High-dose ultraviolet A1 (UVA1) phototherapy: does it work? PMID- 9372520 TI - Narrow-band (311 nm) UVB phototherapy: an audit of the first year's experience at the Massachusetts General Hospital. PMID- 9372521 TI - What is actinic prurigo in Britain? AB - Actinic prurigo (AP) belongs to the group of idiopathic photodermatoses sharing a predilection for occurring more commonly in females, and there is much controversy as to whether it is only a more severe form of polymorphous light eruption (PMLE) or whether it is a distinct entity in its own right. The condition is characterised by intensely itchy papules, plaques and nodules, along with excoriations and scars usually starting before puberty, and predominantly involves the sun-exposed areas although it may also affect covered sites. Seasonal exacerbations at the beginning of spring with improvement in the fall are typical, although the lesions frequently do not clear completely in the winter. The disorder may run a chronic course and persist into adulthood, but often spontaneous resolution occurs in late adolescence. Diagnosis is predominantly based on the clinical features, cutaneous irradiation tests and histology often being normal or non-specific. HLA typing has also been performed in both PMLE and AP patients, showing a strong association between HLA-DR4, in particular with the DRB1*0407 subtype, and AP; no HLA association has been found in PMLE. This HLA association is likely to be of pathogenic significance and strongly suggests a critical role for MHC-restricted antigen presentation in the development of photosensitivity AP. PMID- 9372523 TI - Polymorphous light eruption. PMID- 9372522 TI - Actinic prurigo. PMID- 9372524 TI - UVB and PUVA therapies in HIV patients: are they safe? PMID- 9372525 TI - Photodermatitis from ketoprofen with cross-reactivity to fenofibrate and benzophenones. AB - The aim of this study was to evaluate the possibility of cross-reactivity between ketoprofen, fenofibrate and benzophenones because of their structural similarities. Seven patients presenting photodermatitis from ketoprofen underwent patch and photopatch tests. Ketoprofen, fenofibrate, benzophenone 3, benzophenone 10, benzophenone 4, personal medications and topical creams were tested. All patients had positive patch or photopatch tests to ketoprofen and fenofibrate, four patients had positive UVA photopatch tests to benzophenone 3, and two to benzophenone 10. Patients presenting photosensitization to ketoprofen may also have cross-reactivity to fenofibrate and some benzophenones. PMID- 9372526 TI - Factors influencing the photo-reproduction of hydroa vacciniforme lesions. AB - Hydroa vacciniforme vesicles can be reproduced experimentally with repetitive UVA irradiations, but this photo-reproduction is not constant. The aim of this study was to search for the factors that influence photo-reproduction. To reproduce hydroa vacciniforme lesions six patients underwent repetitive UVA and polychromatic irradiations on the back. In four patients out of six, UVA irradiation with high doses induced papulo-vesicular lesions. Photo-induced lesions were very close to those induced by sunlight. Photo-reproduction failed when phototesting was done after or shortly before remission. Therefore, the absence of photo-reproduction appears to be a good prognostic factor. PMID- 9372527 TI - Effect of UVB 311 nm irradiation on normal human skin. AB - Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response. PMID- 9372528 TI - Photoprotective effect of calcipotriol upon skin photoreaction to UVA and UVB. AB - It has been shown that 1,25-dihydroxyvitamin D3 has a photoprotective effect against UVB injury in mouse skin and cultured rat keratinocytes by induction of metallothionein (MT). Calcipotriol is a synthetic analogue of 1,25 dihydroxyvitamin D3 with equipotent cell regulating properties, but with a lower risk of calcium-related side effects. The aim of the present study was to see whether calcipotriol has a photoprotective property both in vitro and in vivo. We examined the effect of calcipotriol on UV-induced damage of cultured human keratinocytes through a cell viability assay, and measurement of DNA synthesis by cultured keratinocytes, on UV-induced damage of mouse skin and on minimal erythema dose (MED). We found that calcipotriol was protective against UVB induced reduction in DNA synthetic activity of cultured keratinocytes in relatively low doses (20 and 40 mJ/cm2) of UVB. With phototesting following application of calcipotriol, five subjects among 10 healthy volunteers and three among six psoriasis patients showed an increase in MED compared with the vehicle treated site. These findings imply that calcipotriol may be photoprotective and that more extensive studies with various doses of UV irradiation and modes of calcipotriol delivery are required. PMID- 9372529 TI - No evidence for a physiological coupling between melatonin and glucocorticoids. AB - Much has been speculated about the existence of a physiological coupling between melatonin and glucocorticoid secretion and about a possible anti-stress action of melatonin. We examined the relationship between melatonin and glucocorticoid secretion under close-to-physiological conditions, when the plasma concentration of either melatonin or glucocorticoids was elevated acutely or chronically in both rats and humans. Tryptophan administration caused a massive rise of plasma melatonin, but had no effect on corticosterone levels in rats or on cortisol levels in humans. The acute and long-lasting exposure of rats to uncontrollable stress resulted in a significant rise of adrenal corticosterone secretion, but had no effect on circulating melatonin levels. Orchectomy caused an initial increase in circulating corticosterone (when melatonin was unaffected) and a delayed rise in circulating melatonin (when corticosterone levels were normalized). In humans, no correlation was found between the nocturnal urinary excretion of melatonin and cortisol, either among healthy subjects, or among patients suffering from panic disorder (with an increased urinary excretion of cortisol) or among insomnia patients (with a high incidence of low melatonin secretion). Furthermore, no evidence was found for a suppressive action of melatonin on dexamethasone-mediated thymus regression in rats and on dexamethasone-mediated suppression of lymphocyte proliferation in vitro. Taken together, the results of this study provide no evidence for the existence of mutual influences between melatonin and glucocorticoid secretion, nor do they support the proposed attenuation of glucocorticoid-mediated effects on target cells or tissues by melatonin under physiological conditions. PMID- 9372530 TI - IBZM SPECT imaging of striatal dopamine-2 receptors in psychotic patients treated with the novel antipsychotic substance quetiapine in comparison to clozapine and haloperidol. AB - We investigated the striatal dopamine-2 (D2) receptor occupancy caused by different antipsychotic substances in 18 psychotic patients (16 with schizophrenic and two with schizoaffective disorder according to DSM-IV) with single photon emission computed tomography (SPECT) using 123I-iodobenzamide (IBZM) as tracer substance. Four patients were treated with the novel antipsychotic compound quetiapine (300-700 mg/day), six with clozapine (300-600 mg/ day) and eight with haloperidol (10-20 mg/day). They were compared with eight healthy controls. Measurement of S/F ratios and consecutive calculation of D2 receptor occupancy revealed a significantly lower striatal D2 occupancy rate with quetiapine and clozapine in comparison to haloperidol. In correspondence with the low striatal D2 receptor occupancy rates and again in contrast to the haloperidol treatment group, there were no extrapyramidal motor side-effects (EPS) in the quetiapine and clozapine treatment groups. Therefore, the reported data support the position that quetiapine can be considered to be an atypical antipsychotic substance due to its relatively weak striatal D2 receptor blocking property and therefore its low propensity to induce EPS. PMID- 9372531 TI - Central 5-HT depletion enhances impulsive responding without affecting the accuracy of attentional performance: interactions with dopaminergic mechanisms. AB - A series of ten experiments examined the effects of profound central 5-HT depletion on attentional performance in the rat in the five-choice serial reaction time task, and also determined the effects of such depletion on responding affected by d-amphetamine and by selective dopamine receptor antagonists. Rats were trained to detect and locate brief visual stimuli randomly presented in one of five spatial locations. When performance had stabilised (> 80% correct, < 20% omissions), selective central 5-HT depletion was induced by intracerebroventricular administration of the neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) following pretreatment with both a noradrenergic and a dopaminergic re uptake inhibitor. The lesioned animals performed the five-choice serial reaction time task with the same degree of accuracy as the sham-operated controls. However, 5-HT depletion reduced the percentage of omitted trials and increased the number of premature/anticipatory responses. This pattern of behaviour following 5-HT depletion could not be attributed to enhanced primary motivation as demonstrated by measures of food intake and latencies to collect food reinforcement. The lesion attenuated the increase of premature responding induced by high doses of systemically administered d-amphetamine. 5-HT depletion also attenuated the dose-dependent decrease in accuracy induced by (-)-sulpiride, a D2 receptor antagonist, although the effects of this drug on response latencies and premature responding were similar in both groups. However, the systemic administration of the D1 receptor antagonist, SCH 23390, blocked the impulsive responding produced by the lesion as indicated by a lack of lesion effects on the percentage of omitted trials and premature responding. The results suggest that central 5-HT depletion results in impulsive, fast responding, which nevertheless does not impair accuracy of visual discrimination performance. The increased impulsivity may be mediated by altered 5-HT-dopamine interactions, with the lesion removing an inhibitory influence over dopamine neurotransmission. PMID- 9372532 TI - Nicotine withdrawal leads to increased sensitivity of serotonergic neurons to the 5-HT1A agonist 8-OH-DPAT. AB - In order to explore the neurophysiology of nicotine withdrawal, we examined the activity of serotonergic neurons in the dorsal raphe nucleus in rats undergoing withdrawal from chronic exposure to nicotine. Animals were exposed to nicotine (6 mg/kg per day base) via SC implanted osmotic minipumps. After 12 days the pumps were removed and the animals allowed to go through spontaneous withdrawal. Rats were anesthetized on various days of the procedure and the effect of the 5 hydroxytryptamine (5-HT)-1A agonist 8-OH-DPAT on the single-unit activity of serotonergic neurons in the dorsal raphe nucleus was examined. The sensitivity of serotonergic neurons to 8-OH-DPAT was not changed by the chronic administration of nicotine or saline; slightly increased on day 2 of withdrawal; significantly increased on days 3 and 4 of withdrawal; and no longer significantly increased by day 7 of withdrawal. These results indicate that serotonergic neurons in the dorsal raphe nucleus have an increased sensitivity to systemically administered 8 OH-DPAT in rats undergoing nicotine withdrawal and that the serotonergic system may play a role in the symptoms of nicotine withdrawal. PMID- 9372533 TI - Use of antisense oligodeoxynucleotide to delta-opioid receptor mRNA in the study of turnover of delta-opioid receptors in the spinal cord of the mouse. AB - Pretreatment of male ICR mice with an antisense oligodeoxynucleotide to delta opioid receptor mRNA (DOR AS oligo, 163 pmol) given intrathecally (i.t.) once a day for 1-3 days produced a time-dependent attenuation of antinociception produced by i.t.-challenged [D-Ala2] deltorphin II (6.4 nmol), a delta-opioid receptor agonist. The attenuation of the [D-Ala2]deltorphin II-induced antinociception caused by pretreatment with DOR AS oligo given i.t. daily was blocked by co-pretreatment with naltriben (14.5 nmol), a delta-opioid receptor antagonist, but was markedly enhanced by concomitant pretreatment with thiorphan (19.7 nmol) or bestatin (14.5 nmol), which inhibits the degradation of endogenously released Met-enkephalin. Concomitant pretreatment with antiserum to Met-enkephalin, but not with antiserum to Leu-enkephalin, beta-endorphin or dynorphin A (1-17), and DOR AS oligo given i.t. daily for 3 days prevented the attenuation of i.t.-challenged [D-Ala2]deltorphin II-induced antinociception caused by the DOR AS oligo pretreatment. Our results support the existence of a turnover of delta-opioid receptors in the mouse spinal cord caused by the release of Met-enkephalin. PMID- 9372534 TI - Amphetamine-induced withdrawal responding: effects of repeated drug administration. AB - The first purpose of this research was to assess withdrawal haloperidol appropriate lever responding 24 h after a single administration of 0.35, 0.75, and 1.00 mg/kg amphetamine. Rats were trained to discriminate among 0.35 mg/kg amphetamine (AM), distilled water (DW), and 0.033 mg/kg haloperidol (HA) in a three-lever drug discrimination task. An increase in HA-appropriate lever responding occurred following the 1.00 mg/kg dose of AM but not after either of the lower doses. The second purpose was to determine the effect of repeated administration of 0.75 mg/kg AM. Two groups of animals were given five administrations of drug, one at an interdose interval (IDI) of 24 h and the other at an IDI of 48 h. Control animals were given injections of DW. Increased HA appropriate lever responding occurred in both of the AM-treated groups. The magnitude of this effect tended to be less in the 48-h IDI group. Thus, even though HA-lever responding was not evident 24 h after a single administration of 0.75 mg/kg AM, it was produced by repeated administration of this dose, even at 48-h intervals. PMID- 9372535 TI - Role of central dopaminergic and 5-hydroxytryptaminergic projections in the behavioral responses elicited by thyrotropin-releasing hormone in rats. AB - The systemic administration of thyrotropin-releasing hormone (TRH) to rats elicits locomotor activation, wet dog shakes, jaw movements, paw licking and tail rattle. Central dopamine (DA) and 5-hydroxytryptamine (5-HT) systems and peripheral vagal afferents have been implicated in these responses. To define this circuitry further, the effects of lesions of these pathways on the behavioral responses elicited by intraperitoneal (IP) injections of TRH were assessed in rats. Lesions of the DAergic innervation of the nucleus accumbens did not affect the locomotor activation, wet dog shakes, paw licking, jaw movements or tail rattle elicited by TRH. This is consistent with our in vivo microdialysis finding that TRH did not affect the release of DA in the nucleus accumbens at a dose that strongly increased locomotor activity. Depletion of spinal 5-HT significantly decreased the wet dog shakes induced by TRH, while depletion of forebrain 5-HT had no effect on any behavior. Bilateral vagotomy did not affect the locomotor response to TRH or any of the other behaviors measured. Taken together these results suggest that the DAergic mesolimbic, the 5-HTergic projections to the forebrain and vagal afferent systems are not mediators of the behavioral responses to systemic TRH. In contrast, the raphe-spinal 5-HTergic projection system may serve to modulate the wet dog shakes elicited by this peptide. PMID- 9372536 TI - Self-administration of cocaine and heroin combinations by rhesus monkeys responding under a progressive-ratio schedule. AB - The present study examined the reinforcing effects of cocaine and heroin, alone and combined, in rhesus monkeys (n = 4) responding under a progressive-ratio (PR) schedule. The PR schedule consisted of five components, each made up of four trials (i.e., 20 trials total), with each trial in a component having the same response requirement. The initial response requirement was fixed-ratio (FR) 120, which doubled across components to a maximum of FR1920. A trial ended with an injection or the expiration of a 15-min limited hold and the inter-trial interval was 30 min. Cocaine dose-response functions (13-400 micrograms/kg per injection) for injections/ session were monophasic, i.e., increased with dose until responding reached an asymptote or a peak. Heroin dose-response functions (1.6 100 micrograms/kg per injection) for injections/session were biphasic functions. i.e., increased to a peak and then decreased, whereas heroin dose-response functions for response rate were monophasic and reached an asymptote. When cocaine (1.6-200 micrograms/kg per injection) was combined with heroin (0.4-6.4 micrograms/kg per injection), low doses of cocaine (3.2-25 micrograms/kg per injection) and heroin (0.4-1.6 micrograms/kg per injection) that did not maintain behavior when tested alone did so when tested in combination. Combination with heroin resulted in a leftward shift in the cocaine dose-response functions, indicating that heroin increased the potency of cocaine as a reinforcer. This heroin-induced increase in cocaine's reinforcing potency may be a contributing factor to abuse of cocaine and heroin combinations (i.e., "speedballs") in humans. However, maximum injections/session for cocaine combined with heroin were not different from cocaine alone, suggesting that the reinforcing efficacy of combinations of cocaine and heroin were not higher than that of cocaine alone. PMID- 9372537 TI - Synergism between buprenorphine and cocaine on the rotational behavior of the nigrally-lesioned rat. AB - Buprenorphine, a partial mu-opioid receptor agonist, has been proposed as a treatment for cocaine abuse. However, studies in animals have produced conflicting results on the nature of the interaction between buprenorphine and cocaine. In some studies, buprenorphine attenuated the effects of cocaine and in others it enhanced them. The purpose of the present study was to evaluate the interaction of buprenorphine and cocaine on the rotational behavior of the nigrally-lesioned rat. Both buprenorphine (0.003-0.1 mg/kg) and cocaine (1.0-30 mg/kg) alone produced dose-dependent increases in rotational behavior. Buprenorphine produced long-lasting turning with a peak at 60 min after administration, while cocaine produced turning that peaked immediately after administration and lasted for about 2 h. To distinguish simple additivity from other possible outcomes, we determined the relative potency of each drug alone, using a defined level of effect: 150 turns above the saline control in 4 h. This effect was produced by 10.0 mg/kg cocaine alone and by 0.0175 mg/kg buprenorphine alone. Based on these results, fixed ratio combinations were tested and the experimentally derived effects were compared to the theoretically additive values, using an isobolographic analysis. The fixed ratio combinations of the two drugs tested produced turning greater than predicted from simple additivity. This finding provides statistically-supported evidence for synergism between the actions of buprenorphine and cocaine. PMID- 9372538 TI - Theory and statistics of detecting synergism between two active drugs: cocaine and buprenorphine. AB - This article discusses the theory and statistical aspects in the design and analysis of experiments to detect synergism between two drugs that produce overtly similar effects. The current analysis extended and simplifies previously published work in this area. Application is made to a study by Kimmel et al. in this issue that examined the combined action of buprenorphine and cocaine in producing turning in rats having unilateral nigrostriatal lesions produced by 6 hydroxydopamine. The use of turning as an endpoint is unusual in quantitative studies of synergism in that no clear maximum effect (turning), could be elicited. Data from the turning study are analyzed statistically and reveal that the combination of buprenorphine and cocaine in each of two fixed ratio mixtures tested is synergistic for this effect. PMID- 9372540 TI - Effects of perinatal anoxia on the acute locomotor response to repeated amphetamine administration in adult rats. AB - We examined the possibility that anoxia at birth can alter behavioral sensitization to amphetamine during adulthood. Male rats born either vaginally or by Cesarean section with or without an additional 15-min period of anoxia received five once-daily injections of either d-amphetamine (2.0 mg/kg, i.p.) or vehicle or no pretreatment. One week later, all animals received a challenge injection of amphetamine (0.5 mg/kg, i.p.). The data indicate that all three birth groups of animals pretreated with amphetamine had sensitized equally to the drug's behavioral effect. Of animals pretreated with saline, however, only those born by Cesarean section with added anoxia displayed a sensitized response to amphetamine, suggesting that the stress of daily injection was sufficient to sensitize these animals to amphetamine. These findings provide experimental support for clinical evidence implicating obstetric complications, such as perinatal anoxia, in the pathophysiology of schizophrenia. PMID- 9372539 TI - Gamma-vinyl GABA attenuates cocaine-induced lowering of brain stimulation reward thresholds. AB - Gamma-vinyl GABA (GVG, also referred to as vigabatrin), an irreversible inhibitor of GABA transaminase (GABA-T), raises levels of GABA in nerve terminals, inhibits striatal dopamine release, and attenuates cocaine-induced increases in extracellular dopamine in the striatum and nucleus accumbens. In order to determine the action of GVG on dopamine-mediated reward, we examined its effects on the threshold for rewarding brain stimulation in male F-344 rats. GVG dose dependently raised brain stimulation reward (BSR) thresholds at doses of 200, 300, and 400 mg/kg without significant effects on motor performance as measured by response latencies. In order to determine if GVG had similar modulatory effects on cocaine-induced lowering of BSR thresholds, the effective doses of GVG were co-administered with 2.5 and 5.0 mg/kg cocaine, doses that significantly lower BSR thresholds. The 400 mg/kg dose of GVG significantly blocked the lowering of thresholds seen at each dose of cocaine. Cocaine in combination with 200 or 300 mg/kg GVG, doses of GVG that significantly raise BSR thresholds, resulted in thresholds not significantly different from those obtained with cocaine alone. These data demonstrate that, at the doses tested, GVG is more effective at modulating basal reward thresholds that at modulating thresholds lowered by cocaine, implying that as dopaminergic activity increases, GABAergic activity must also increase in order to exert its inhibitory influence on dopaminergic activity. PMID- 9372542 TI - Aminoglutethimide, a corticosteroid synthesis inhibitor, facilitates brain stimulation reward in food-restricted rats: an investigation of underlying mechanisms. AB - It was previously observed that the corticosteroid synthesis inhibitor, aminoglutethimide (AG), markedly facilitates lateral hypothalamide (AG), markedly facilitates lateral hypothalamic self-stimulation (LHSS) in food-restricted rats. This effect is not present 30 min after injection when plasma corticosterone levels are suppressed, but rather at 2 h when corticosterone has recovered from suppression. In experiment 1, it was confirmed that AG (50.0 mg/kg, s.c.) lowers the threshold for LHSS in food-restricted rats but not in control rats that have ad libitum access to food. This effect occurred independently of whether food restriction, by itself, lowered threshold. Experiment 2 examined whether the facilitation of LHSS coincides with biosynthetic rebound of corticosteroid precursors. While a pregnenolone surge was demonstrated by radioimmunoassay, dose response testing with exogenous pregnenolone and progesterone (0.1, 1.0 and 10.0 mg/kg, s.c.) failed to confirm the prediction that one of these precursors facilitates reward. Therefore, a general test of the involvement of adrenocortical biosynthetic events was conducted in experiment 3 where rats were adrenalectomized (ADX) or sham-operated prior to food restriction. Surprisingly, ADX did not diminish the effect of AG. This finding raises the possibility of a CNS, rather than adrenal, site of action. AG is known to penetrate the blood brain barrier and exert weak anticonvulsant effects. The facilitation of reward may result from central inhibitory effects of the drug and share a common basis with the enhanced reinforcing potency of other CNS depressants in food-restricted rats. PMID- 9372541 TI - A PET-study of [11C]FLB 457 binding to extrastriatal D2-dopamine receptors in healthy subjects and antipsychotic drug-treated patients. AB - We recently developed [11C]FLB 457 a substituted benzamide with the very high affinity of 20 pM for D2-dopamine receptors in vitro. The aim of the present exploratory study was to examine the anatomical distribution of [11C]FLB 457 binding in the human brain and to determine extrastriatal D2-receptor occupancy in antipsychotic drug-treated patients. [11C]raclopride was used to obtain reference values for D2-dopamine receptor occupancy in the putamen. After IV injection of [11C]FLB 457 there was a high concentration of radioactivity, not only in the caudate putamen but also in the thalamus and the temporal cortex. The concentration of radioactivity in the frontal cortex, the substantia nigra and the colliculi was slightly higher than in the cerebellum. Pretreatment with haloperidol and fluphenazine indicated that [11C]FLB 457 binding in extrastriatal regions to a high degree represent specific binding to D2-dopamine receptors. The D2-occupancy in antipsychotic drug-treated patients was on the same level in the thalamus and the temporal cortex as that determined with [11C]raclopride in the putamen. The study shows that [11C]FLB 457 has potential for quantitative PET examination of D2-dopamine receptors in man. PMID- 9372543 TI - Physiologic and cytotoxic effects of tirapazamine in tumor-bearing mice. AB - Tirapazamine, a new bioreductive agent currently advancing through clinical trials, may have a valuable role to play in cancer therapy. In vitro, the drug shows markedly more toxicity to hypoxic cells than to aerobic cells, and preferential activity against hypoxic cells of solid tumors in vivo also can be inferred in many investigations. However, we have previously reported that tirapazamine has minimal activity against cells in the center of hypoxic spheroids, raising concerns with regard to whether the drug may be bioreductively inactivated before reaching chronically hypoxic tumor cells. We consequently examined the oxygen-dependent differential activity of tirapazamine in solid tumors in vivo by using fluorescence-activated cell sorting with clonogenicity assays for cell viability or with the comet assay for DNA damage. The preferential activity of tirapazamine against hypoxic vs. aerobic tumor cells in vivo was approximately threefold, much less than the factors of 50-500 typically seen in vitro. Interestingly, we also found that tirapazamine administration often modified tumor blood flow in the murine models, an effect that could be of clinical utility in sufficiently sensitive tumor cells. Taken together, our observations suggest that sequencing of tirapazamine with other agents requires careful consideration in the clinic. PMID- 9372544 TI - Increased injection number enhances adenoviral genetic radiotherapy. AB - Intratumoral injection of an adenoviral vector containing radiation-inducible DNA sequences of the early growth response gene (Egr-1) promoter ligated to a cDNA encoding tumor necrosis factor-alpha (TNF-alpha; Ad.Egr-TNF) increases the radiation killing of a human radioresistant xenograft (SQ-20B). Viral dose escalation experiments demonstrated that SQ-20B growth inhibition correlated with viral titer. Injection of 5 x 10(8) PFU Ad.Egr-TNF produced regression to a mean volume of 22 +/- 13% of the original tumor volume, 1 x 10(8) PFU to a mean of 62 +/- 24%, and 5 x 10(7) PFU to a mean of 67 +/- 27%. No regression was observed when tumors were injected with 1 x 10(7) PFU Ad.Egr-TNF or with the null viral vector (Ad.null). When two injections of vector (2 x 10(8) PFU Ad.Egr-TNF) were combined with 50 Gy, a significant increase in tumor regression was observed compared with injection of buffer, Ad.Egr-TNF, or 50 Gy. The interactive killing between TNF and radiation was enhanced significantly (P = 0.05) when the number of injections was increased from two to five while maintaining a constant viral titer (2 x 10(8) PFU Ad.Egr-TNF) and a constant radiation dose (50 Gy). Significant TNF-alpha levels were present in irradiated vs. unirradiated tumors following injection with Ad.Egr-TNF. Taken together, these data suggest that the volumetric reduction produced by the combined effects of Ad.Egr-TNF and radiation is enhanced with increasing vector concentration and the number of vector injections. PMID- 9372545 TI - Treatment of recurrent pelvic and selected primary gynecologic malignancies with 241Am. AB - The purpose of this study was to update the experience and demonstrate the effectiveness and limitations of 241Am applicators for previously irradiated patients and for selected patients with primary gynecologic malignancies. Between October 1986 and May 1994, 30 patients were treated with 241Am. The median patient age was 68 years, ranging from 41 to 91 years. Patients were retrospectively categorized by treatment intent, i.e., palliative vs. curative. Patients undergoing curative therapy were further classified as to whether 241Am brachytherapy was directed at microscopic residua after surgery or to gross primary tumor. Of the 30 patients, 18 had recurrent pelvic malignancies from various primary sites and were reirradiated with 241Am for palliation. Six patients had microscopic disease after surgical resection and were managed with postoperative radiotherapy (RT) that included 241Am. Six patients had gynecologic cancers managed with primary RT that included treatment with 241Am. Overall, 50% (9/18) of the patients with recurrent pelvic malignancies were locally controlled after reirradiation with 241Am. Including surgical salvage, the ultimate local control rate was 61% (11/18). Postoperative 241Am with or without external beam radiation therapy (XRT) was effective in 83% (5/6) of the patients with microscopic disease. Including surgical salvage, 100% (6/6) of the patients were ultimately free of disease. Fifty percent (3/6) of the patients treated with primary RT that included 241Am brachytherapy experienced local control. Including surgical salvage, 67% (4/6) of the patients were ultimately controlled with 241Am. In conclusion, reirradiation utilizing 241Am was effective in palliating patients with recurrent pelvic malignancies. 241Am was effective in 83% (5/6) of the patients with microscopic disease managed with postoperative RT. 241Am was of marginal benefit in patients with gynecologic tumors managed with primary RT. PMID- 9372546 TI - Bioreductive alkylating agent porfiromycin in combination with radiation therapy for the management of squamous cell carcinoma of the head and neck. AB - Porfiromycin (methyl mitomycin C) has been shown in laboratory studies to have increased preferential cytotoxicity to hypoxic cells and therefore may provide enhanced therapeutic efficacy over mitomycin C when used in combination with radiation therapy (RT). The purpose of the two clinical studies reported here is to evaluate the concomitant use of porfiromycin with RT in the management of squamous cell carcinoma of the head and neck. Between October 1989 and July 1992, 21 patients presenting with locally advanced stage III/IV squamous cell carcinoma of the head and neck were entered into a phase I toxicity trial evaluating porfiromycin as an adjunct to RT. Patients were eligible if they had biopsy documented squamous cell carcinoma of the head and neck with a low probability of cure by conventional means. Patients were treated with standard fractionated daily RT to a total median dose of 63 Gy, with porfiromycin administered on days 5 and 47 of the course of RT. Upon completion of this phase I trial, a phase III trial was initiated in November 1992 randomizing patients with squamous cell carcinoma of the head and neck to RT with mitomycin C vs. RT with porfiromycin. There is no radiation only arm in this current trial. To date, 75 patients have been entered on this trial and acute toxicity data are available on 67 patients (34 porfiromycin, 31 mitomycin C) who have completed their entire course of treatment. Median follow-up of the 21 patients enrolled in the phase I porfiromycin trial is 58.5 months. Of the 21 patients, 5 were treated at a dose of 50 mg/M2, 4 at 45 mg/M2, and the final 12 at 40 mg/M2, which appeared to result in acceptable acute hematological and nonhematological toxicities. As of December 1995, 14 of the 21 patients have died with disease and 7 remain alive and free of disease, resulting in a 5-year actuarial survival of 32%. Of the patients enrolled to date in the phase III randomized trial of mitomycin C vs. porfiromycin, there have been no statistically significant differences between the two arms with respect to white blood cell count (WBC), platelet, or hemoglobin nadirs. Acute nonhematological toxicities including mucositis, epidermitis, odynophagia, and nausea have also been comparable. Two patients in this current randomized trial died during treatment, apparently of nondrug related causes. We conclude that the bioreductive alkylating agent porfiromycin has demonstrated an acceptable toxicity profile to date. Final analysis of the phase I trial, which revealed a 5-year no evidence of disease survival rate of 32% in patients with locally advanced disease and a low probability of cure, appears encouraging. We anticipate completion of the current ongoing trial comparing mitomycin C to porfiromycin in the next 2 years. Further investigations, including large-scale multiinstitutional trials employing bioreductive alkylating agents or other hypoxic cell cytotoxins as adjuncts to RT, are warranted. PMID- 9372547 TI - Results of local excision followed by postoperative radiation therapy for rectal cancer. AB - There is increasing interest in the use of local excision and postoperative radiation therapy (RT) as a sphincter-sparing approach for selected rectal cancers. The data suggest that this treatment approach should be limited to patients with either T1 tumors with adverse pathologic factors or T2 tumors. Transmural (T3) tumors have a 25% local recurrence rate with this technique and are treated more effectively with standard surgery and pre- or postoperative therapy. The results of local excision and postoperative RT are encouraging, however, more experience is needed to determine if this approach will have similar local control and survival rates as standard surgery. PMID- 9372549 TI - Improvement of image quality in megavoltage computed tomography with second generation scanning mode. AB - Megavoltage computed tomographic (CT) scanning is a topic of interest in precision radiation therapy. It is useful in verifying and improving the accuracy of the patient's positioning. For this purpose, we developed a third generation mode megavoltage CT scanner. However, insufficient spatial resolution limits its clinical usefulness. A second generation mode megavoltage scanner using a turntable has been newly developed to investigate whether improvements in spatial sampling could result in image quality high enough for clinical use. Scanning is composed of 11 rotations and 12 translations of the table. The scanning beam is a 3 MV X-ray, and the detector consists of 75 elements of cadmium tungstate crystals combined with photodiodes. A spatial resolution of 0.5 mm and contrast resolution of approximately 5% were obtained. The image quality is inferior to that of conventional diagnostic CT scanners, but is estimated to be adequate for some clinical applications of radiation therapy. Based on the satisfactory results, a new third generation megavoltage CT scanner is under investigation. PMID- 9372548 TI - Patient self-assessment of complications and quality of life after conformal neutron and photon irradiation for localized prostate cancer. AB - Although neutron irradiation for prostate cancer has been associated with significant morbidity, pilot data in patients with early stage disease suggested that conformal neutron and photon irradiation was well tolerated without severe complications. A self-assessment questionnaire was mailed to the first 83 patients treated with conformal neutron and photon irradiation to objectively evaluate the impact on quality of life of this regimen. In total, 75 patients (90%) returned the completed questionnaire. These patients had received either 9 neutron Gy (N Gy) plus 38 photon Gy (50 patients) or 10 N Gy plus 38 photon Gy (33 patients) for stage T1/T2 N0 M0 prostate cancer (Gleason score < or = 7). The irradiated volume included the prostate and seminal vesicles with a 1.5 cm margin. Neutrons were delivered as a boost to the prostate only with a non-axial four field beam arrangement. Approximately 50% of the dose to the prostate was from neutron irradiation. Follow-up ranged from 6 to 25 months (median 13 months). The questionnaire used was a validated quality of life instrument used previously in patients treated with surgery or radiation. Prior to irradiation, 29% of patients reported urinary symptoms and 11% had prostate surgery (TURP). At follow-up, 23% reported persistent urinary symptoms. Of these, 21% dripped a few drops of urine, 3% used pads but none leaked > 1 tablespoon/day. One patient underwent surgery to dilate a urethral stricture. Although 55% of patients had gastrointestinal symptoms during radiation therapy, only 26% had persistent symptoms at the time of questioning. These included minor rectal bleeding in 20% and significant hematochezia in 3%. Of the 85% of patients able to obtain full or partial erections prior to irradiation, 87% maintained their potency. Fifteen percent sought treatment for impotence. Overall, at last follow-up, 84% felt little or no physical discomfort, 91% were very satisfied with their treatment, and 97% would choose radiation therapy again. This patient self-assessment questionnaire confirmed that this regimen of conformal neutron and photon irradiation resulted in levels of chronic toxicity acceptable to the patient. PMID- 9372550 TI - Target-dependent synaptogenesis: inductive effect of pituitary melanotrophs on their central innervation. AB - The glandular activity of the vertebrate pituitary intermediate lobe (IL) is regulated by direct cellular innervation, in contrast with the purely humoral regulation of adjacent pituitary anterior lobe (AL). Thus in the rat IL, melanotrophs receive a dopaminergic and GABAergic innervation from the basal hypothalamus, which tonically inhibit their glandular activity. We studied this model of neuron-target interactions in cocultures in defined medium of fetal hypothalamic neurons with neonate pituitary glandular cells. In the cocultures with IL cells, neuroglandular contacts occurred after 4 days in vitro (DIV) but required another 8 DIV to exhibit ultrastructural and immunocytochemical features of fully differentiated functional synapses; by contrast, neuroneuronal synapses developed much faster and could already be detected after 4 DIV. In the cocultures with AL cells, neuroglandular contacts never mature in differentiated synapses. Confocal microscope observation revealed that dopaminergic neurons, which represented less than 1% of total neurons in the cocultures, established 50% of the synapses detected on the melanotrophs. These cells are thus able, contrary to the AL cells, to promote the establishment of functional synapses and, to some extent, to select their specific innervation. PMID- 9372551 TI - Substantia nigra pars reticulata single unit activity in normal and 60HDA lesioned rats: effects of intrastriatal apomorphine and subthalamic lesions. AB - The spontaneous activity and the response to intrastriatal application of apomorphine of substantia nigra pars reticulata (SNpr) single units was studied in four experimental groups of rats: (1) normal rats; (2) subthalamic nucleus (STN) lesioned rats; (3) rats bearing a 6-hydroxydopamine (60HDA) lesion; and (4) 60HDA-lesioned animals with an additional STN lesion. Thirty-eight percent of units from 60HDA-lesioned rats showed a bursting pattern of spontaneous activity, which was never found in normal rats. STN lesions had no effect on the spontaneous activity of SNpr units from normal rats, but reduced the percentage of burst units in 60HDA-lesioned animals. Intrastriatal apomorphine produced responses in 62% of SNpr units from normal rats and 85% of units from 60HDA lesioned animals (P < 0.05). In addition, the modifications in the firing rate and in the coefficient of variation of the interspike intervals induced by intrastriatal apomorphine were significantly greater for the units isolated from 60HDA-lesioned rats. In particular, it was noted that all the burst units responded to apomorphine, showing the highest changes in firing rate and coefficient of variation. However, intrastriatal apomorphine did not always turn the activity of burst units into a more physiological pattern. STN lesions reduced the percentage of units responding to intrastriatal apomorphine in normal rats. In 60HDA-lesioned rats, STN lesions reduced the number of responsive units, and their change in mean firing rate and coefficient of variation. Our results show that the STN participates in the genesis of the bursting pattern of activity of SNpr units in 60HDA-lesioned rats, and that STN lesions can partially revert the abnormal spontaneous and apomorphine-induced responses of SNpr units in these animals. PMID- 9372552 TI - Increased neostriatal dopamine activity after intraperitoneal or intranasal administration of L-DOPA: on the role of benserazide pretreatment. AB - L-DOPA provides the most potent medication to treat Parkinson's disease, and such systemic treatment is usually combined with a peripheral amino acid decarboxylase inhibitor to amplify its central effectiveness. Since L-DOPA can lose its efficacy or can lead to adverse effects with prolonged application, current pharmacokinetic and dynamic research is aimed at improving the drug's applicability. In a previous study, performed with in vivo microdialysis in the anesthetized rat, we have shown that intranasal L-DOPA administration (without prior decarboxylase inhibition) can increase extracellular dopamine levels in the neostriatum. Using similar experimental conditions in the present experiment, we tested the neurochemical effects of L-DOPA treatment in combination with the peripheral amino acid decarboxylase inhibitor benserazide. In accordance with other data, it was found that the combination of i.p. benserazide and i.p. L-DOPA led to pronounced increases of extracellular levels of dopamine, dihydroxyplenylacetic acid and homovanillic acid in the neostriatum, whereas i.p. L-DOPA alone only moderately increased dopamine, but strongly increased the metabolite levels. Furthermore, increased dopamine levels, and weaker increases of dihydroxyplenylacetic acid and homovanillic acid were observed after i.p. benserazide followed by intranasal L-DOPA. Finally, we found that i.p. benserazide alone can lead to pronounced increases in neostriatal dopamine and moderate increases of dihydroxyplenylacetic acid levels, whereas it did not affect homovanillic acid. Thus, not only the combination of L-DOPA (i.p. or intranasal) with the presumed peripheral L-DOPA decarboxylase inhibitor benserazide, but also each component alone can affect dopamine activity in the brain. Especially the findings with benserazide treatment might be of relevance for understanding the mechanisms of current L-DOPA therapy, since they indicate that part of the treatment's actions may possibly be determined by central dopaminergic effects of the accompanying amino acid decarboxylase inhibitor. PMID- 9372553 TI - Fluoxetine-induced desensitization of somatodendritic 5-HT1A autoreceptors is independent of glucocorticoid(s). AB - Previous in vitro studies showed that glucocorticoid receptor activation (notably by corticosterone) could induce a functional desensitization of somatodendritic 5 HT1A autoreceptors in the dorsal raphe nucleus [Laaris et al. (1995) Neuropharmacology 34:1201-1210], similar to that due to in vivo subchronic treatment with a 5-HT reuptake inhibitor, such as fluoxetine, in rats. In the present study, we investigated whether a link might exist between these effects, i.e., whether glucocorticoid receptor activation could be responsible for the fluoxetine-induced desensitization of 5-HT1A autoreceptors. In vitro recording in the dorsal raphe nucleus of brain-stem slices showed that subchronic treatment with fluoxetine (5 mg/kg intraperitoneally (i.p.), daily for 3-7 days) significantly reduced the potency of the 5-HT1A receptor agonist ipsapirone to inhibit the firing rate of serotoninergic neurons. Parallel experiments in adrenalectomized and sham-operated rats indicated that subchronic fluoxetine treatment produced a similar shift to the right of the ipsapirone inhibition curve in both groups of animals. Furthermore, the subchronic blockade of glucocorticoid receptors by RU 38486 (25 mg/kg subcutaneously (s.c.), daily) in intact rats treated with fluoxetine (5 mg/kg i.p., daily for 3 days) did not affect the ability of the latter treatment to reduce the potency of ipsapirone to inhibit the firing of serotoninergic neurons. These data suggest that glucocorticoid receptors (and their possible activation by corticosterone) are not involved in the functional desensitization of somatodendritic 5-HT1A autoreceptors, which occurs during long-term treatment with a serotonin reuptake inhibitor such as fluoxetine. PMID- 9372555 TI - Distribution of adenosine receptors in the postmortem human brain: an extended autoradiographic study. AB - Whole-hemisphere sections from six subjects were used in a quantitative autoradiographic study to characterize and to investigate the distribution of adenosine receptors, using [3H]DPCPX, [3H]CGS 21680, and [3H]SCH 58261 as radioligands. [3H]DPCPX-binding showed the pharmacology expected for adenosine A1 receptors and is therefore taken to mirror adenosine A1 receptors. Adenosine A1 receptors were widely distributed, with the highest densities in the stratum radiatum/pyramidale of the hippocampal region CA1. Adenosine A1 receptors were nonhomogeneously distributed in nucleus caudatus, globus pallidus, and cortical areas: In the cingulate and frontal cortex the deep layers showed the highest labeling, while in the occipital, parietal, temporal, and insular cortex it was highest in the superficial layers. In addition, we found very high levels of adenosine A1 receptors in structures known to be important for cholinergic transmission, especially the septal nuclei. The Bmax values and KD values for [3H]DPCPX-binding in stratum radiatum/pyramidale of CA1 and the superficial layer of insular cortex were 598 and 430 fmol/mg gray matter and 9.9 and 14.2 nM, respectively. [3H]CGS 21680-binding was multiphasic, but showed the pharmacology expected for adenosine A2A receptors and was taken to represent them. Adenosine A2A receptors were abundant in putamen, nucleus caudatus, nucleus accumbens, and globus pallidus pars lateralis. Specific [3H]CGS 21680-binding was also found in certain thalamic nuclei and throughout the cerebral cortex. The adenosine A2A receptor antagonist radioligand [3H]SCH 58261 was also found to label these extrastriatal structures. Thus, adenosine A2A receptors seem to be more widely distributed in the human brain than previously recognized. PMID- 9372554 TI - Agonist-induced morphologic decrease in cellular D1A dopamine receptor staining. AB - The distribution of D1A dopamine (DA) receptor proteins was assessed by using subtype specific antireceptor antisera after acute DA exposure. The immunofluorescent staining of D1A DA receptor protein expression was examined in (1) stably transfected Chinese hamster ovary (CHO) cells, (2) primary striatal cell cultures, and (3) rat striatal brain slices. After agonist exposure as brief as 2 min and as long as 60 min, profound loss of immunofluorescent D1A receptor protein staining occurred in each paradigm. Additionally in the tissue slice, immunofluorescent neuropil staining for the receptor protein also was attenuated. The DA-induced alteration in receptor protein staining was blocked by the antagonist (+)-butaclamol and by the selective D1-family antagonist SCH 23390. Receptor staining patterns reverted back to the control immunofluorescent distribution within 15 min after removing the agonist from the bath. Immunofluorescence for the second-messenger cyclic AMP increased at all DA exposure times in the three experimental paradigms, was blocked by D1-family antagonists, and decreased to basal staining after brief recovery periods. This demonstrated the functional integrity of the D1A receptor in target cells. Pretreatment with the mitogenic plant lectin concanavalin A blocked the immunofluorescent decrease in receptor staining but not the elevation of the second messenger, indicating a morphologic distinction in these two events, parallel to other biochemical reports. The data suggested that a morphologic basis of acute homologous D1A DA receptor desensitization may be transposition of membrane-surface receptors to a transiently unavailable, intracellular compartment. This finding is supported by specific fluorescence incorporation of FM1-43, used as a marker of endocytosis, in CHO cells treated with DA. PMID- 9372556 TI - Striatal 6-[18F]fluorodopa accumulation after combined inhibition of peripheral catechol-O-methyltransferase and monoamine oxidase type B: differing response in relation to presynaptic dopaminergic dysfunction. AB - The aim was to investigate the effects of inhibition of monoamine oxidase type B (MAO-B) with selegiline alone and the combined inhibition of peripheral catechol O-methyltransferase (COMT) with entacapone and MAO-B with selegiline on striatal 6-[18F]fluorodopa (FDOPA) accumulation, and whether the effect of entacapone + selegiline on FDOPA uptake differed depending on the severity of the presynaptic dopaminergic dysfunction. Thus, eight healthy controls, eight de novo patients with Parkinson's disease (PD), and 18 levodopa-treated PD patients were investigated with positron emission tomography (PET). Half of the subjects in each population belonged to the selegiline group and half to the entacapone + selegiline group. Both groups were studied twice with PET using FDOPA. After the first (baseline) FDOPA PET investigation, both groups were on 2 weeks of selegiline treatment, 10 mg daily. Thereafter, the second FDOPA PET was performed for all subjects with a premedication administered 60 min before the PET imaging; one group received 10 mg of selegiline, and the other group received a single 400 mg dose of entacapone coadministered with 10 mg of selegiline. Selegiline treatment alone had no significant influence on striatal FDOPA metabolism. The FDOPA accumulation, expressed as striatal-to-occipital ratios and modified decarboxylation coefficients (k3R0), increased significantly after entacapone + selegiline administration in all subject populations. The FDOPA uptake rate constant (Ki) remained virtually unchanged in controls and in de novo patients but decreased significantly in levodopa-treated PD patients after entacapone + selegiline intake. Entacapone + selegiline administration did not influence significantly the unidirectional blood-to-brain clearance for FDOPA (K1D) or the relative dopadecarboxylase activity (k3D). The changes in the studied parameters after entacapone + selegiline administration probably reflect the effects of entacapone, since entacapone alone has caused similar changes in previous PET studies. Response in FDOPA accumulation to entacapone + selegiline was higher in controls and de novo patients compared with levodopa-treated PD patients. The milder response in levodopa-treated patients might reflect the reduced ability of the degenerated dopaminergic neurons to utilize the prolonged FDOPA availability, produced by entacapone. PMID- 9372557 TI - Concentration and occupancy of dopamine transporters in cocaine abusers with [11C]cocaine and PET. AB - The concentration (Bmax) of the dopamine transporter (DAT) and the maximum and effective occupancies by cocaine doses of 0.1 mg/kg or 0.05 mg/kg were measured in the striatum of cocaine abusers (n = 12) by using [11C]cocaine as a radiotracer for the DAT and positron emission tomography (PET). Two methods based on a three-compartment model with one binding site (the nonlinear least squares (NLSQ) and the Farde pseudoequilibrium method) were used to estimate Bmax. Effective occupancies and maximum occupancies were calculated from the distribution volume ratios (DVR) and a three-compartment model, respectively. The NLSQ and Farde methods gave similar values of Bmax (average, 650 +/- 350 pmol/ml and 776 +/- 400 pmol/ml, respectively), but the individual estimates of Bmax were found to be very sensitive to small variations in other model parameters and were not correlated with the parameter Bmax/Kd (r = .07). The average maximum (and effective) occupancies were found to be 67% (50%) and 52% (39%) for the 0.1-mg/kg and the 0.05-mg/kg studies, respectively. The ED50 based on the effective occupancy corresponds to 0.1 mg/kg, which is significantly smaller than the ED50 of 3 mg/kg calculated from studies in which [123]beta-CIT is displaced by cocaine. The effect on the Bmax estimate of two binding sites with different Kd's is also considered by simulation. We conclude (1) that the lack of robustness in the Bmax estimate limits the usefulness of any one subject's Bmax and suggests that the combination parameter Bmax/Kd (or the DVR), which has been used extensively, is a more stable measure of free receptor/transporter concentration. The average Bmax may, however, provide an estimate of the expected concentration in humans. (2) The DVR can be used as a measure of DAT occupancy without applying an explicit model. PMID- 9372559 TI - Desensitization of mutant acetylcholine receptors in transgenic mice reduces the amplitude of neuromuscular synaptic currents. AB - While the slow onset of desensitization of nicotinic acetylcholine receptors (AChRs), relative to the rate of acetylcholine removal, excludes this kinetic state from shaping synaptic responses in normal neuromuscular transmission, its role in neuromuscular disorders has not been examined. The slow-channel congenital myasthenic syndrome (SCCMS) is a disorder caused by point mutations in the AChR subunit-encoding genes leading to kinetically abnormal (slow) channels, reduced miniature endplate current amplitudes (MEPCs), and degeneration of the postsynaptic membrane. Because of this complicated picture of kinetic and structural change in the neuromuscular junction, it is difficult to assess the importance of the multiple factors that may be responsible for the reduced endplate current amplitudes, and ultimately the clinical syndrome. In order to address this we have used a transgenic mouse model for the SCCMS that has slow AChR ion channels and reduced endplate responsiveness in the absence of any of the degenerative changes. We found that the reduction in MEPC amplitudes in these mice could not be explained by either reduced AChR number or by reduced AChR channel conductance. Rather, we found that the mutant AChRs in situ manifested an activity-dependent reduction in sensitivity that caused diminished MEPC and endplate current amplitude with nerve stimulation. This observation demonstrates that the basis for the reduction in MEPC amplitudes in the SCCMS may be multifactorial. Moreover, these findings demonstrate that, under conditions that alter their rate of desensitization, the kinetic properties of nicotinic AChRs can control the strength of synaptic responses. PMID- 9372558 TI - Differential expression of D1 and D2 dopamine and m4 muscarinic acetylcholine receptor proteins in identified striatonigral neurons. AB - Large families of genetically distinct G-protein coupled receptor subtypes mediate dopamine's (D1-D5) and acetylcholine's effects (m1-m5). A functional balance of dopamine and acetylcholine may be based in part on the differential expression of receptor subtypes by distinct neuron subpopulations. The localization of the D1 and D2 receptors, the predominant dopamine receptors in neostriatum, to distinct subpopulations of striatal projection neurons has been controversial. In addition, m4 receptor localization to specific striatal projection neuron subpopulations is also at question. To determine whether rat striatonigral neurons differentially express D1, D2, and m4 receptor proteins, we combined immunocytochemistry by using receptor subtype specific antibodies and retrograde tracing with cholera toxin-colloidal gold. D1 and m4 receptor immunoreactivity was visualized in 95% and 92% of identified striatonigral neurons, respectively. By contrast, D2 receptor immunoreactivity was visualized in only 1% of these neurons. These findings support models of basal ganglia in which D1 and D2 receptors are segregated, as well as indicate that D1 and m4 are colocalized. These cellular distributions may be important substrates for the putative DA/ACh balance that is implicated in certain movement disorders. PMID- 9372560 TI - External monitoring of cerebral nicotinic acetylcholine receptors in living mice. PMID- 9372562 TI - Thoraxsonography--Part II: Peripheral pulmonary consolidation. AB - In many cases of pulmonary diseases extending up to the pleura, ultrasound (US) helps to identify the etiology of the lesion. There are several sonomorphological criteria to differentiate peripheral pulmonary consolidations. Pneumonic infiltration shows a hypoechoic inhomogeneous echo texture, with multiple air inlets and bronchoaerograms. Fluid bronchogram indicates an obstructive pneumonitis. Pulmonary infarctions are visible in different stages as triangular pleural-based lesions in most cases of pulmonary embolism. The diagnostic accuracy of chest sonography in pulmonary embolism was 85%-90%. US-guided transthoracic biopsy shows a diagnostic yield of > 90% in malignancies and 50% 83% of benign lesions. The overall complication rate is very low: 1%-2% hemoptysis, 2%-4% pneumothoraces and 1%-2% requiring chest tube drainage. Color Doppler US can demonstrate the vascular patterns and may help in the understanding of underlying pathophysiology. Sonographic examinations of the upper and central mediastinum provide good results in 90-95% of cases. Some anatomical limitations of transcutaneous US can be circumvented by endoluminal US. PMID- 9372563 TI - Doppler ultrasound in the evaluation of cirrhotic patients: the prevalence of intrahepatic arteriovenous shunting, and implications for diagnosis of hepatocellular carcinoma. AB - To establish the prevalence and significance of Doppler-detected hepatic arteriovenous shunting (AVS) in patients with compensated cirrhosis, 115 patients (mean age 55.4 +/- 12.47 SD y) were prospectively screened using real-time ultrasound with pulsed Doppler at 2.5 MHz to detect focal liver lesions and quantify AVS. Focal masses were biopsied and correlated with the US findings. All other patients had clinical follow-up and imaging for at least 12 months. AVS occurred in 28 of 115 (24.3%), and in 18 of 20 proven malignancies (90%) including 11 of 13 cases of hepatocellular carcinoma (85%). However, 9 of 28 (32%) AVS (mean Doppler shift 2.73 +/- 1.51 [SD] kHz [range 0.6-5.41 kHz], n = 9) were in regions of fatty infiltration (4) or isolated (5), unassociated with malignancy. At a prevalence of 17.9% malignancy (11.3% due to hepatocellular carcinoma), specificity for malignancy increased with shunt velocity, from 76% (for mass alone), to 94.8% for mass with AVS, 96.8% for a mass with AVS of 1.75 2.4 kHz, and 100% for a mass with AVS > 2.4 kHz. Doppler US is useful in characterizing liver lesions in cirrhotic patients: the majority of malignant hepatic lesions are associated with AVS and specificity for malignancy increases with shunt velocity. However, isolated AVS or AVS associated with focal fat may be detected in 7.8% of compensated cirrhotics. PMID- 9372561 TI - Thoraxsonography--Part I: Chest wall and pleura. AB - The fact that ultrasound (US) waves are reflected completely by the bony thorax and are erased from the aerated lung to a large extent led to the mistaken notion that sonography is not a very useful diagnostic tool for use in this region. On the other hand, since the beginning of US imaging, reports have been published regularly on pleuropulmonary sonographic diagnostic and therapeutic procedures. Rib fractures could be detected about twice as often by US than x-ray. With regard to determining the nodal status in neoplastic disease of the axilla and supraclavicular fossa, US is superior to palpation. In imaging pleural effusions, US is more accurate than chest film and is useful in determining the nature of the pleural effusion. Sonographic evidence of pleural nodules is a specific finding in patients with a malignant effusion. Chest sonography is a useful diagnostic tool for critically ill patients with chest diseases. Performed at the bedside, this technique can be particularly helpful when computed tomography is not available or when critically ill patients cannot be moved. PMID- 9372564 TI - Umbilical venous pulsation and regional circulatory disturbance. AB - The umbilical cord conditions at the point where regional umbilical venous pulsation occurred were examined in 15 patients between the 28th and 40th gestational week. The patients delivered appropriate-for-date infants without anomalies. Regional venous pulsation was observed in cases of large-angle cord winding (especially more than 60 degrees). It was also observed where the umbilical cord was compressed by the fetus, uterine wall or placenta, even if the umbilical cord was straight. From these findings, we concluded that regional umbilical venous pulsation is the result of regional circulatory disturbance of the umbilical cord. PMID- 9372565 TI - Decay constant of Doppler flow waveform as a possible indicator of ovarian malignancy. AB - The objectives of this study were to analyze the decay constant (tau) of the Doppler flow waveform in ovarian tumors; to determine if differences in this constant can discriminate between malignant and benign ovarian tumors; and to compare the decay constant to the known resistive index (RI), in order to determine its potential prognostic application. Patients with ovarian masses (46) were evaluated in a retrospective study; 13 had malignant tumors, 7 showed tumors with low malignant potential (LMP), 11 had benign masses, 4 had secondary ovarian metastases and 11 had functional ovarian masses. Doppler flow waves measured in the ovary before operation were analyzed from archival videotapes. The RI was calculated preoperatively, and the decay constant of the flow waveform was analyzed retrospectively. We approximated the decaying portion of the flow waveform from the systolic peak to the diastolic level to an exponential curve. Then, the decay constant associated with the flow signal was compared for different types of ovarian pathology. Ovaries with malignancies showed significantly higher mean values for the decay constant (89.7; 95% confidence interval 60.0-119.3) than those with benign tumors (41.8; 25.7-57.9) (p < 0.007), where tau is provided in pixels (in this study each pixel equals approximately 11.4 ms). The mean RI value for malignant tumors was 0.44 +/- 0.12 whereas, in benign tumors, it was 0.622 +/- 0.11. For the benign tumors, both tau and RI did not differ significantly from the measured indices in LMP tumors, metastases and functional ovarian findings. In addition, when the cutoff value of tau was set at 48, 92.3% of all malignancies were identifiable using only tau. This preliminary study indicates that the decay constant of the Doppler flow waveform is able to discriminate between malignant and benign masses and may, thus, provide substantial assistance as an additional parameter in the diagnosis of malignant ovarian tumors in postmenopausal patients. PMID- 9372566 TI - Critical comparison of indices and threshold values for assessing placenta performance using Doppler ultrasound. AB - To determine the most appropriate index and an optimal cutoff value for obstetric Doppler ultrasound, the umbilical and uterine arteries of 467 patients were examined during the third trimester using an Acuson 128 color Doppler system. Doppler ultrasound detection of chronic placental insufficiency with fetal growth retardation and acute placental insufficiency with subpartal asphyxia were selected as criteria. A birth weight below the 10th percentile (using Hohenauer's percentiles) was taken as the parameter for the former and a 5-minute Apgar score of < 8 for the latter criterion. For each artery, two risk groups were studied: 103 patients with chronic and 27 patients with acute placental insufficiency. Using EROC curves, the prediction of chronic and acute placental insufficiency was computed for six Doppler indices (maximum systolic, mean [TAMX] and maximum end-diastolic velocities, S/D ratio, RI, PI) and 10 threshold values per index (the 1st to 50th percentiles for the qualitative indices and the 50th to 99th percentiles for the quantitative indices). The following results were obtained: (1) the development of chronic placental insufficiency was predicted best in Doppler examinations of the umbilical artery by calculating the PI with the 60th percentile as the threshold value, and in examinations of the uterine artery by determining the S/D ratio with the 90th percentile; 2nd (2) acute placental insufficiency was predicted best by calculating the mean blood flow velocity (TAMX) in the umbilical artery, with the 50th percentile as the ideal cutoff value; in examinations of the uterine artery the best results were obtained by determining the S/D ratio with the 90th percentile as cutoff value. Three conclusions may be drawn from the results: (1) taken overall, the qualitative Doppler parameters (S/D ratio, RI, PI) are superior to the quantitative parameters (maximum systolic, mean [TAMX] and maximum end-diastolic velocity) in the detection of both chronic and acute placental insufficiency; (2) in Doppler examinations of the umbilical artery the optimal threshold value is in the region of the 60th, and in examinations of the uterine artery in the region of the 90th, percentile; and (3) chronic placental insufficiency was detected better than the acute form; examinations of the umbilical artery yielded more explicit data than those of the uterine artery. PMID- 9372567 TI - Preliminary study in differential contrast echography. AB - Microbubble-based contrast agents have backscattering properties that differ greatly from those of soft tissues. These agents exhibit nonlinear scattering properties in response to incident acoustic energy, causing harmonic components in reflected energy. Even in linear scattering conditions, an important difference is observed in the frequency dependence of their backscatter coefficient, when compared to that of tissues. In this situation, any such differential behaviour can be exploited by imaging instrumentation to enhance the detection of agent-containing vessels against background tissue. The resulting B mode image brightness (or pixel level) can thus be the representation of a local parameter computed from radio frequency (rf) signal processing of the raw echoes. The object of this article is to report on parametric imaging studies performed with Sonovue (formerly code named BR1, Bracco Research SA), aimed at assessing the contrast-enhancing potential of spectral rf signal processing. The technique used, termed here "differential contrast echography" (DCE), is applicable in real time B-mode imaging. It is based on an on-line subtractive approach, using dual channel signal processing to implement differential filtering and demodulation. In this preliminary work, DCE was implemented off-line, on rf echo signals digitised from commercial B-mode scanners. Data acquisition, DCE processing and complete B-mode image reconstruction were programmed on a personal computer. The images presented were produced from test phantoms as well as animal phased array scanning. The phantom included a flow channel, background scattering material, fixed echogenic targets and echo-free regions. Animal scanning was performed on rabbit liver. The results obtained from DCE show promising contrast-enhancing properties. The regions containing no contrast agent are significantly suppressed from the image, preferentially leaving the regions perfused by the contrast agent. This property was favourable to experimenting with image-overlay presentations, superimposing colour-coded DCE imaging with standard log compressed grey-scale B-mode, in a way analogous to duplex imaging combining colour Doppler and B-mode. PMID- 9372568 TI - Characterisation of red and white thrombus by intravascular ultrasound using radiofrequency and videodensitometric data-based texture analysis. AB - Visual assessment of intravascular ultrasound (IVUS) video images cannot reliably identify thrombus. We examined if texture analysis of radiofrequency (r.f.) data or videodensitometric data (VD) could distinguish thrombi of different ages and cell compositions. Whole human blood (red clot = RC), platelet-rich plasma (white clot = WC) and plasma (n = 6/group) were imaged at 4 and 24 h with 30 MHz IVUS transducers. At 4 h, VD- and r.f.-based analyses revealed significant differences between RC and WC with variance (VD red 26.4 +/- 2.5, white 33.9 +/- 7.8; r.f. red 1.4 +/- 0.5, white 4.9 +/- 1.3), kurtosis (VD red 0.29 +/- 0.9, white 0.23 +/ 0.3) and skewness (VD red 0.23 +/- 0.13, white 0.35 +/- 0.52; r.f. red 0.06 +/- 0.01, white -0.06 +/- 0.05). Also mean grey-level from both data sets was higher in RC (VD 134.8 +/- 18.0; r.f. -13.3 +/- 1.2) than in WC (VD 105.3 +/- 17.4, r.f. 16.5 +/- 2.2) (p < 0.01). With increasing time, variance increased in WC (5.5 +/- 1.5 at 24 h) and decreased in RC (0.9 +/- 0.3.3 at 24 h). The more heterogeneous structure of WC may be distinguished from that of RC using texture analysis of either VD or r.f.-signals. PMID- 9372569 TI - Quantitative acoustic characterization of a new surfactant-based ultrasound contrast agent. AB - The acoustic properties of a new ultrasound contrast agent, ST68, have been investigated. ST68 is a sonicated mixture of nonionic surfactants (Span-type and Tween-type) consisting of stabilized microbubbles with a mean diameter of 3.8 microns and a concentrations of 7.1 x 10(8) bubbles/mL. A pulsatile flow system was used to acquire data in vitro. The acoustic properties of ST68, as a function of time, frequency and dose, were calculated. Enhancement changed nonlinearly with contrast agent dose; maximum was 13.1 dB +/- 1.0 dB for a dose of 0.30 microL/mL of suspending medium. Attenuation reached approximately 11 dB/cm for dosages above 0.27 microL/mL and for frequencies between 2.5 and 6.0 MHz. In vivo, i.v. injections of ST68 were given to 4 rabbits (doses from 0.01 to 0.23 mL/kg). A clear increase in flow signal intensity was observed for 1 to 2 min. An in vivo dose-response curve was calculated from audio Doppler signals obtained with a 10-MHz cuff transducer placed around the distal aorta. Maximum enhancement was 18.3 dB +/- 3.13 dB for a 0.13 mL/kg dose. Moreover, ST68 appears to follow a simple relationship between in vivo enhancement and dose. In conclusion, ST68 is capable of producing marked vascular enhancement. Its acoustic properties have been characterized in vitro and in vivo. PMID- 9372570 TI - Three-dimensional freehand ultrasound: image reconstruction and volume analysis. AB - A system is described that rapidly produces a regular 3-dimensional (3-D) data block suitable for processing by conventional image analysis and volume measurement software. The system uses electromagnetic spatial location of 2 dimensional (2-D) freehand-scanned ultrasound B-mode images, custom-built signal conditioning hardware, UNIX-based computer processing and an efficient 3-D reconstruction algorithm. Utilisation of images from multiple angles of insonation, "compounding," reduces speckle contrast, improves structure coherence within the reconstructed grey-scale image and enhances the ability to detect structure boundaries and to segment and quantify features. Volume measurements using a series of water-filled latex and cylindrical foam rubber phantoms with volumes down to 0.7 mL show that a high degree of accuracy, precision and reproducibility can be obtained. Extension of the technique to handle in vivo data sets by allowing physiological criteria to be taken into account in selecting the images used for construction is also illustrated. PMID- 9372571 TI - Echo machine-imposed limit on transmitral spectral Doppler velocity-profile analysis. AB - We have previously developed a kinematic model of ventricular filling. Its application to in vivo transmitral Doppler velocity profiles provides a quantitative characterization of filling. However, the model parameters computed by solving the "inverse problem" may depend on ultrasound machine type and setting (e.g., gain, baseline filter, dynamic range). To determine machine-based effects on the computed model parameters, we performed a flow phantom study using Acuson and HP echocardiography machines at various settings. We compared maximum velocity envelopes (MVEs), as well as the model fit to these MVEs, for 3 simulated waveforms imaged by both machines. For all 3 waveforms, the machines generated comparable MVEs, fit by the model within a mean-square difference of 5E 5 (m/s)2. The associated variations in model parameters for the 3 waveforms were not uniform. Two waveforms showed slight variation between machines, with model parameters varying by less than 6%. The shortest duration waveform showed model parameter variations of 10-15%. Analysis of the parameter space for this waveform showed a constant mean-square error contour that was larger than that for the other two, causing similar small variations in measured MVEs to result in larger differences in the parameter estimates for this waveform. Because this method completely eliminates inter- and intraobserver variability, we conclude that, within the limits established, the slight contour variations due to machine type and setting should not affect this method's applicability in clinical Doppler flow analysis. PMID- 9372573 TI - The stimulation of bone formation in vitro by therapeutic ultrasound. AB - A controlled study was performed to evaluate the effects of different ultrasound (US) intensities on 5-day-old mouse calvaria bone in tissue culture. A special technique to apply the US was developed, and the following parameters were measured: collagen and noncollagenous protein (NCP) synthesis (bone formation), and temperature change. It was found that ultrasound at 0.1 W/cm2 (SATA), pulsed 1:4, 3 MHz, 5 min, significantly stimulates bone formation (i.e., the synthesis of collagen and NCP) (p < 0.001 and p < 0.01). However, pulsed ultrasound at higher doses (1.0-2.0 W/cm2 (SATA), pulsed 1:4, 3 MHz, 5 min) significantly inhibited the synthesis of both collagen and NCP (p < 0.05). The temperature measurements showed a maximum rise of 1.8 degrees C [at 2.0 W/cm2 (SATA)] and no detected rise at 0.1 W/cm2 (SATA), suggesting that the effects in this study were primarily nonthermal. These results may reflect the healing effect of US on fractures and osteoradionecrosis and reinforces the use of low intensity US regimens [0.1 W/cm2 (SATA)] in clinical practice. PMID- 9372572 TI - Hemolysis of 40% hematocrit, Albunex-supplemented human erythrocytes by pulsed ultrasound: frequency, acoustic pressure and pulse length dependence. AB - The dependence of hemolysis produced by pulsed ultrasound on ultrasound frequency, acoustic pressure and pulse length was explored. Human erythrocytes (40% hematocrit; in Albunex-supplemented autologous plasma) were exposed (60 s) to 20 or 200 microns pulses of ultrasound at frequencies of 1.02, 2.24 or 3.46 MHz and at peak negative pressures [P-] ranging from 0.0 to approximately 3.0 MPa in 0.5 MPa increments. The duty factor was 0.01. At each frequency, hemolysis increased with increasing acoustic pressure and depended weakly on pulse duration. At relatively high acoustic pressures, hemolysis depended strongly on ultrasound frequency; at lower pressures, the frequency dependence was weaker. The potential clinical significance of ultrasonic hemolysis is discussed. PMID- 9372574 TI - Shock-wave measurement using a calibrated interferometric fiber-tip sensor. AB - The results of shock-wave measurements using a calibrated fiber-tip sensor based on a Michelson interferometer are presented. A transfer function, obtained by an independent experiment that describes the properties of the sensor system, was used to correct the measured shock-wave data in the Fourier frequency domain. The phase of the transfer function was determined from its amplitude by a fitting procedure using minimum-phase terms. As an example of application, the acoustic output field of an electromagnetic lithotriptor was investigated, and the shock wave source was reliably characterized. The measured data provide a basis for estimating the hazard to which a patient is exposed during shock-wave treatment and for optimizing a lithotriptor system to produce a sharply localized and effective acoustic field. PMID- 9372575 TI - A thermal beam-shape phantom for ultrasound physiotherapy transducers. AB - Acoustic beam nonuniformities are not uncommon in physiotherapy ultrasound equipment and can lead to errors in delivered dose. A relatively simple thermal technique is described for mapping the intensity distribution in physiotherapy ultrasound beams that could be used for routine QA checks. The technique uses a thermochromic material sandwiched between layers that absorb ultrasound. The structure is used in a water bath to intersect the ultrasound beam. Thermal models predict that, with suitable absorbing materials and careful control of the surface temperature of the layers, sufficient spatial resolution and sensitivity can be achieved to show the intensity distribution in physiotherapy ultrasound beams. Thermal images of sections through physiotherapy ultrasound beams using this method correlate well with corresponding intensity maps generated by planar scanning with a hydrophone. PMID- 9372576 TI - Technical limits in transcranial Doppler recording: inadequate acoustic windows. AB - Transcranial Doppler (TCD) is a technique that evaluates blood flow velocity in intracranial vessels. It uses a 2-MHz probe and a Doppler signal analyzer. Absence of an acoustic window is a considerable problem for clinical utilization of TCD because cerebrovascular patients are frequently elderly. Previous reports suggest a higher prevalence of inadequate temporal acoustic window (TAW) in aged subjects and in females. A consecutive series of 624 subjects (376 males and 248 females, age range 2-86 y) were evaluated by standard TCD examination, to assess the contemporary absence of any signal corresponding to insonated basal arteries, defined as inadequate acoustic window. The rate of inadequate TAW was 8.2%, that of inadequate occipital acoustic window (OAW) was 9.0%. Prevalence of inadequate TAW was higher in females than in males, and OAW was higher in males than in females. Influence of aging on the presence of inadequate acoustic window is confirmed for temporal, but not for the occipital window. Different anatomical characteristics of the 2 regions could explain the different prevalence of TAW and OAW. PMID- 9372577 TI - The pathophysiology of stress urinary incontinence in women and its implications for surgical treatment. AB - Stress urinary incontinence is a symptom that arises from damage to the muscles, nerves, and connective tissue of the pelvic floor. Urethral support, vesical neck function, and function of the urethral muscles are important determinants of continence. The urethra is supported by the action of the levator ani muscles through their connection to the endopelvic fascia of the anterior vaginal wall. Damage to the connection between this fascia and muscle, loss of nerve supply to the muscle, or direct muscle damage can influence continence. In addition, loss of normal vesical neck closure can result in incontinence despite normal urethral support. Although the traditional attitude has been to ignore the urethra as a factor contributing to continence, it does play a role in determining stress continence since in 50% of continent women, urine enters the urethra during increases in abdominal pressure, where it is stopped before it can escape from the external meatus. Perhaps one of the most interesting yet least acknowledged aspects of continence control concerns the coordination of this system. The muscles of the urethra and levator ani contract during a cough to assist continence, and little is known about the control of this phenomenon. That operations cure stress incontinence without altering nerve or muscle function should not be misinterpreted as indicating that these factors are unimportant. PMID- 9372578 TI - Surgical treatment of sphincteric incontinence in women. AB - There are many surgical options to correct sphincteric incontinence. The choice should take account of clinical features, urodynamic data and operation characteristics. Success should be evaluated both subjectively and objectively and it is desirable to have at least a two year follow-up. It is necessary to be aware of the complications of each procedure. Where new techniques are described it is important to use objective outcome measures. PMID- 9372579 TI - The UCLA surgical approach to sphincteric incontinence in women. AB - Stress urinary incontinence (SUI) in the female may be treated by a variety of non-surgical and surgical therapies. However, once the patient has chosen to undergo operative repair the ideal procedure is based on three considerations: the degree of anterior vaginal wall prolapse, the degree of incontinence and associated anatomic abnormalities requiring surgical repair. In the vast majority of cases vaginal wall sling is our procedure of choice for the surgical treatment of SUI in the female. Vaginal wall sling is based on sound anatomic principles, may be performed as an outpatient procedure and is equally efficacious for the treatment of SUI due to anatomic incontinence (urethral hypermobility) and intrinsic sphincter deficiency. Since vaginal wall sling is performed through a transvaginal approach, other associated manifestations of pelvic floor prolapse such as rectocele can be addressed and repaired simultaneously. When necessary the vaginal wall sling can be easily modified to repair large grade cystoceles. PMID- 9372580 TI - The Gore-tex sling procedure for female sphincteric incontinence: indications, technique, and results. AB - We constructed a pubovaginal sling using the Gore-tex Soft Tissue Patch and 2-0 polytetrafluoroethylene (PTFE) suspension suture and placed it in 122 consecutive incontinent women with urethral hypermobility and/or intrinsic sphincter deficiency. We performed a retrospective outcome analysis using a questionnaire based telephone survey. The mean follow-up period was 24.4 months. Stress incontinence was cured in 88% of patients (equally effective in type II and type III incontinence), de novo postoperative urinary frequency occurred in 32% of cases, and preoperative urinary frequency resolved postoperatively in 51% of patients. Significant urinary obstruction occurred in 5% of patients. Vaginal granulation tissue with exposed sling occurred in 4% of patients. There was no urethral or bladder erosion. The treatment of female stress incontinence with a PTFE sling is effective and durable with minimal complications. Furthermore, this technique addresses many of the presumed technical shortcomings of endoscopic needle suspensions. PMID- 9372581 TI - The use of bone anchoring in the surgical management of female stress urinary incontinence. AB - Recent reviews have noted failures of transvaginal surgical procedures designed to cure female stress urinary incontinence (SUI). Modifications continue to be applied to improve the transvaginal approach, including anchoring of the supporting sutures to the pelvic bones, reduction of the transvaginal dissection to help reduce further prolapse, and simpler techniques to allow a wider use of sling procedures. This paper reports on the use of a bone-anchoring technique and preservation of the endopelvic fascia in both transvaginal suspension surgery for hypermobility and sling surgery for intrinsic sphincteric deficiency. Results show an 81.7% cure rate in 71 patients who underwent the bone-anchor suspension and were followed for at least 3 years; a 97.5% cure rate in 40 patients who underwent an in situ sling procedure with bone anchoring and were followed for at least 2 years; and a 94% cure rate in 78 patients who underwent a sling procedure with autologous or synthetic material and bone anchoring and were followed for at least 2 years. The use of this bone-anchoring technique and preservation of the endopelvic fascia appears to enhance the success rate without increasing the risk to the patient and, as minimally invasive procedures, reduce the surgery time and the length of hospitalization, thus reducing costs. PMID- 9372582 TI - Periurethral collagen injection for male and female sphincteric incontinence: indications, techniques, and result. AB - Intrinsic sphincter deficiency is characterized by a poorly functioning intrinsic urethral sphincter, which leaks urine at relatively low pressures. Patients with this sort of incontinence are candidates for collagen implant therapy. Collagen is injected in the region of the bladder neck with success, depending on the precise placement of the collagen. There is generally a need to implant more collagen into men. The percentage of patients showing improvement in their incontinence after therapy is 58-100%. Over time the collagen is absorbed and there is a need to repeat the treatment. Collagen increases the abdominal leak point pressure without reducing the flow rate or increasing the residual volume. Treatment failure does not prevent the performance of other procedures. PMID- 9372583 TI - Antegrade techniques of collagen injection for post-prostatectomy stress urinary incontinence: the Washington University experience. AB - Treatment of sphincteric incontinence after radical retropubic prostatectomy remains a clinical challenge. Antegrade techniques of collagen injection are a relatively new method for treatment of post-prostatectomy incontinence. Early experience with this approach has demonstrated improved outcomes compared to the traditional retrograde technique. Overall response rates of 70% cure or significant improvement compare favorably with previously reported series. The theoretical advantages of this method include improved visualization of vesicourethral anastomosis and improved access to the bladder neck. Furthermore, suprapubic catheter drainage avoids the risks of collagen molding around the catheter. The use of a flexible cystoscope for this approach is a recent modification. The smaller diameter of the flexible cystoscope has facilitated access and reduced anesthetic requirements. This system affords unimpeded delivery of collagen to regions of the bladder neck where the submucosa accommodates the injectable agent. In addition, this modality allows more precise needle positioning to provide correct angle and depth of penetration into the submucosal plane. Short-term success rates of this procedure are encouraging and suggest that it may become the primary approach. While these antegrade techniques are more aggressive than the traditional retrograde approach, they are relatively simple and draw upon principles familiar to all urologists. It is hoped that the new flexible antegrade approach will further improve our results. Longer-term follow-up studies with larger numbers of patients will be required to see whether we can accomplish this goal. PMID- 9372584 TI - Use of the artificial urinary sphincter in men and women. AB - There are numerous therapeutic options for treating incontinence. Implantation of an artificial genitourinary sphincter is an excellent choice in cases of incontinence due to sphincteric dysfunction. In this article we report the Mayo Clinic data from several large series and compare these data to other recent reviews. In addition, we review current recommendations regarding patient selection and evaluation. There were 458 patients who underwent implantation of an artificial sphincter, including 417 men and 41 women. The overall continence rate was 88.2%, the reoperation rate was 23.1%, and the mechanical reliability was 88%. Satisfaction rates were greater than 90%. We conclude that artificial sphincter implantation is safe, reliable and very effective in treating incontinence due to sphincteric dysfunction in properly selected patients. PMID- 9372585 TI - Gracilis muscle transposition with electrical stimulation for sphincteric incontinence: a new approach. AB - Neurovascularly intact gracilis-muscle transposition to the proximal urethra is an exciting new technique for sphincteric incontinence. The functional urethral closure of gracilis myoplasty assures dryness, permits intermittent self catheterization when necessary, and avoids the risks of erosion associated with the artificial urinary sphincter. Electrical stimulation of the transposed muscle (dynamic urethral myoplasty) using intramuscular electrodes and a subcutaneously placed pulse generator can alter the molecular physiology of the gracilis muscle from that of predominantly fast-twitch to that of slow-twitch fibers that are fatigue-resistant and more suitable for long-term sphincter function. PMID- 9372586 TI - Antimicrobial and genotoxic activities of N-hydroxyalkyl-1, 2-benzisothiazol 3(2H)-one carbamic esters. AB - N-Hydroxyethyl- and N-hydroxypropyl-1,2-benzisothiazol-3(2H)-one carbamic esters were prepared in order to test their activity against representative bacterial and fungal strains. The obtained results were compared with those reported for parent alcohols and some interesting considerations were drawn. None of the studied derivatives possess genotoxic activity in the Bacillus subtilis rec-assay and Salmonella-microsome test. PMID- 9372587 TI - Isosteres of chiral clofibric acid analogs: synthesis, resolution, absolute configuration and HPLC detection of the optical purity. AB - Both racemic and enantiomeric forms of some isosteres of chiral clofibric acid analogs have been synthesized. Also, the absolute configuration has been established by chemical correlation and the optical purity determined by a simple HPLC procedure. Moreover, these studies show that the isosteric substitution of the ether oxygen atom of alpha-aryloxy-alkanoic acids with sulfur, amino and methylene groups lead to compounds in which both biological activity and stereoselectivity regarding chloride channel are highly reduced. PMID- 9372588 TI - Heterocycles with a benzothiadiazepine moiety. 5. Derivatives of pyrrolo[2,1 d][1,2,5]benzothiadiazepine, a novel tricyclic ring. AB - The synthesis of pyrrolo[2,1-d][1,2,5]benzothiadiazepin-7(6H)-one 5,5-dioxide has been achieved by reaction between 2-(1H-pyrrol-1-yl)benzenesulfonamide and triphosgene. N-Ethylation of the tricyclic derivative afforded 6-ethylpyrrolo[2,1 d][1,2,5] benzothiadiazepin-7(6H)-one 5,5-dioxide, also obtained by the action of trifosgene on N-ethyl 2-(1H-pyrrol-1-yl)benzenesulfonamide. Preparation of pyrrole derivatives from 2-aminobenzenesulfonamide and its N-ethyl derivative by Clauson-Kaas procedure required preliminary protection of the sulfonamide function. PMID- 9372589 TI - Studies on annelated 1,4-benzothiazines and 1,5-benzothiazepines. XI. Synthesis and biological activity of several naphtho- and quinolino-1,4-thiazine and -1,4 thiazepine derivatives containing the imidazole ring. AB - Several derivatives of naphthol[1,2-b]imidazo[1',2'-d]-1,4-thiazine and -1,4 thiazepine and imidazo[1',2'-4,5]-1,4-thiazino[3,2-c]quinoline and -1,4 thiazepino[3,2-c] quinoline have been synthesized. These compounds and other imidazo[2,1-d][1,5]benzothiazepine derivatives, previously synthesized, have been tested for their possible pharmacological activities. One of these substances displayed inhibitory activity on CNS, others showed an appreciable antiinflammatory effect. None of the naphtho and quinolino derivatives showed affinity for the benzodiazepine receptor. PMID- 9372590 TI - General and cardiac toxicity of doxorubicin-loaded gelatin nanoparticles. AB - General and cardiac toxicity of doxorubicin loaded gelatin nanoparticles cross linked by glutaraldheyde were investigated in healthy rats. The rats were treated with free doxorubicin (DXR), unloaded nanoparticles (UNp), physical mixture of doxorubicin and unloaded nanoparticles (DRX/UNp), and DXR-loaded nanoparticles (DXR-Np). Each group of animals received the same dose of DXR (3 mg/kg) via i.p. once a week. Both electrocardiogram (ECG) parameters and body weight were measured 24 h before each administration. Rats treated with UNp behaved as controls. DXR/UNp provoked the same toxic effects as free DXR. On the contrary, DXR-Np resulted more toxic since significant variations of both the body weight and the ECG parameters were observed during the first week of treatment. In addition, the rats treated with DXR-Np died between the 3rd and the 5th day after the 2nd administration. These results demonstrate that, in these experimental conditions, the couplage of DXR to nanoparticles enhanced the cardiotoxicity of the drug. Since DXR was linked to the protein matrix of nanoparticles via glutaraldehyde, the high toxicity of DXR-loaded nanoparticles could be due to the covalent binding of the drug to the carrier. PMID- 9372591 TI - Some new methyl-8-methoxypsoralens: synthesis, photobinding to DNA, photobiological properties and molecular modelling. AB - The tricyclic structure of known natural photochemotherapeutic drugs such as 8 methoxypsoralen and 5-methoxypsoralen is often taken as a model in the search of new photosensitizer agents with less phototoxic and mutagenic effects. This paper describes the synthesis, characterization, photobinding to DNA, photobiological properties and computational chemistry of some 8-methoxypsoralen derivatives bearing two or three methyl groups at the key positions of the two photoactive double bonds. Results showed that photoreactivity and photobiological behaviour depend on the pattern of methyl substitutions. Antiproliferative activity in cell lines shows good correlation with DNA interaction data. PMID- 9372592 TI - Zupan's descriptors in QSAR applied to the study of a new class of cardiotonic agents. AB - Recently a new class of molecular descriptors has been proposed and used in QSAR with simulated data and with regression performed by neural networks. In the present paper these descriptors (Zups, from the name of their author, Juri Zupan) have been slightly modified and then applied to a real data set with the aim of studying the structure-activity relationships of a new class of cardiotonics. Forty-one molecules (thirty-seven milrinone analogues, the two lead compounds amrinone and milrinone, and two commercial products) have been studied using classical chemometrical techniques such as PCA (Principal Components Analysis) and PLS (Partial Least Squares regression). Zups describe essentially the local geometry of the molecules. They show promising performances, as compared with other classical geometrical descriptors (as molecular volume, etc.), both in that regards the overall performances, measured by the C.V. Explained variance and in the interpretability of the regression equation. However they have not all the requirements of a good structure representation. Moreover some selectable parameters seem to have a great importance, so that the refinement of the regression model requires time and the evaluation step must be performed in condition of full-validation, because predictive optimisation is used in the selection of parameters, and the final model must be checked on molecules never used to refine the model or, in this case, the parameters of the structure representation. PMID- 9372593 TI - Isosteric replacement of amide by ester function. Synthesis and benzodiazepine receptor affinity of indol-3-ylglyoxylyl ester derivatives. AB - A number of benzyl and phenylethyl esters of indol-3-ylglyoxylic acid were synthesized and tested for their ability to displace [3H]Ro 15-1788 binding from bovine brain membranes. In these new compounds the oxygen atom of the ester function replaced the amide NH group of a class of previously described indolylglyoxylylamides, since it is reported in literature that in the beta carboline series an ester function is more favourable to the activity than an amide group. However, none of the compounds showed an affinity at the Benzodiazepine receptor higher than that of the corresponding amides, demonstrating that the presence of the amide NH group is favourable to the interaction of ligands with the receptor site. PMID- 9372594 TI - Adenosine deaminase inhibitors: synthesis, diastereoisomeric resolution and biological activity of 1-(2-hydroxy-3-nonyl)-1,2,4-triazole-3-carboxamide. AB - The synthesis and the diastereoisomeric resolution of 9-(2-hydroxy-3-nonyl)-1,2,4 triazole-3-carboxamide (8e and 8t) were undertaken in order to investigate the structural requirements of the adenosine deaminase inhibitory site, through simplification of the purine moiety of 9-(2-hydroxy-3-nonyl)adenine (1a, EHNA). The new compounds resulted to be good inhibitors of the enzyme, the erythro isomer being more potent than the threo one (8e, Ki = 0.11 microM vs 8t, Ki = 1.4 microM). However, the triazole derivatives did not show enhancement of inhibitory activity in comparison with the previously reported imidazole analogue 1b (Ki = 0.035 microM). PMID- 9372595 TI - Synthesis, biological activity and conformational studies of geometrically restricted tripeptide analogues of the chemoattractant HCO-Met-Leu-Phe-OMe. AB - The formyl tripeptides containing 2-azetidinecarboxylic acid 2, 2 piperidinecarboxylic acid 3 and norvaline 4 in position 2 were synthesized and their biological activity was evaluated. The conformation of peptides was studied by CD and FT-IR techniques. While 2 and 3 do not show either chemotactic activity or superoxide production, 4 retains both activities. PMID- 9372596 TI - Transdermal iontophoresis of salmon calcitonin can reproduce the hypocalcemic effect of intravenous administration. AB - Salmon calcitonin (sCt) was administered by transdermal iontophoresis in rabbits, using a new drug reservoir assembled directly on the skin, based on a dry disc containing sCt to be dissolved at the application site. The hypocalcemic effect was taken as a measure of the pharmacodynamic response. In rabbits, the results obtained show that salmon calcitonin skin penetration by iontophoresis, using pulsatile current of 0.8 mA/cm2 on a reservoir containing 100 IU/Kg of sCt, was governed by the quantity of electric charge applied, mimicking the hypocalcemic response of 10 IU/Kg intravenous administration. PMID- 9372597 TI - Chiral resolution, configurational study and pharmacological profile of 2 phenoxypropionic acids. AB - The racemates and several enantiomers of 2-phenoxypropionic acids, bearing alkyl, acetyl, benzyl, benzoyl, phenyl, difluorophenyl, Cl, NO2 groups on the aromatic moiety, were investigated as potential analgesic-antiinflammatory drugs. The enantiomers, whose absolute configuration has been previously determined by us, were prepared by chiral resolution of the diastereoisomeric salts of the racemates with cynchonidine. The enantiomeric excess was determined by chiral chromatography. The chiroptical properties of the dextroisomers were investigated by CD. The pharmacological properties of the racemates and the enantiomers were monitored by analgesic-antiinflammatory activity tests as well as by gastrotolerability and acute toxicity tests. Some compounds were shown to be superior to ASA and ketoprofen because they have higher or similar analgesic properties, with less gastroulcerogenetic activity. Furthermore low acute toxicity was found for the compounds with high values of ED50. Correlations between the configuration of the enantiomers and their activity are not evident. For the most active compounds, the activity of one of the enantiomers is superior to that of the racemates. This is particularly true for (S)-3, (R)-15 and (S)-18. PMID- 9372598 TI - Plasma concentration and brain penetration of the H3-receptor antagonist thioperamide in rats. AB - Thioperamide is a potent and selective H3-receptor antagonist, whose in vivo effects have been reported after systemic administration. Some questions have arisen about its ability to cross the blood-brain barrier, since different experimental conditions have given different results in rats, namely a low brain/blood ratio at low doses (10 mg/Kg) and a much higher one at higher doses (60 mg/Kg). In this work we demonstrate the dose-dependence of thioperamide pharmacokinetics, measuring its plasma and cerebral levels after i.p. administration of different doses to rats. Both the plasma half-life and brain penetration of thioperamide resulted as being dose-dependent: when administered to 80 g body weight Wistar rats at 10 mg/Kg i.p., the drug has a short half life (120') and a rather poor brain penetration, but increasing the dose (to 20, 40 and 60 mg/Kg) gives rise to a prolongation of its persistence in the blood (up to 600' at highest dose) and a higher brain penetration. Also, the profile of the plasma concentration curve varies from the dose of 10 to that of 20 mg/Kg, passing from a mono-exponential decrease to a more complex one characterized by an apparent distribution phase. The different distribution processes can be interpreted in the light of thioperamide protein binding and affinity for lipophilic tissues: protein binding can prevent brain penetration (but not distribution to other tissues) at lower doses, while at higher doses the free plasma fraction increases and it can allow passive distribution to lipophilic tissues such as brain tissues. A re-distribution from these tissues and plasma is probably responsible for the strong increase in half-life at high doses. PMID- 9372599 TI - In vitro characterization of potency, affinity and selectivity of H3-antagonists: from thioperamide to thioperamide unrelated imidazole derivatives. AB - This paper summarizes the findings obtained for three different series of original compounds designed as potential H3-antagonists starting from thioperamide structure. The compounds were tested in functional and binding assays to estimate their potency, affinity and selectivity for histamine H3 receptors. Among them, many non-thiourea/isothiourea derivatives acted as selective H3 competitive antagonists and, particularly, 4(5)-[2-[4(5) cyclohexylimidazol-2-ylthio]ethyl] imidazole (dIII) proved to be the most potent H3 blocker vs (R)-alpha-methylhistamine in electrically-stimulated ileum. This imidazole derivative, devoid of thiourea dependent toxic effects, with high affinity displaced biphasically [3H]-N alpha-methylhistamine bound to rat brain H3 sites. Thus, such compound could be proposed as the prototype molecule for the development of new non-thiourea/isothiourea H3-antagonists and as experimental tool to explore the intriguing question of H3 receptor heterogeneity. PMID- 9372600 TI - Synthesis of (+)-(1'R,2'S) and (1'S,2'R)-6,11-dimethyl-1,2,3,4,5,6 -hexahydro-3 [[2'-(alkoxycarbonyl)-2'-phenylcyclopropyl]methyl]-2 ,6 -methano-3-benzazocin-8 ol. Comparison of the affinities for sigma 1 and opioid receptors with in the diastereoisomeric MPCB and CCB. AB - The synthesis and the in vitro receptor affinity for sigma 1 and opiod receptors of the two diastereoisomers of (+)-cis-MPCB namely, (+)-cis-(1'S,2'R)-6,11 Dimethyl-1,2,3,4,5,6 -hexahydro-3-[[2'-(methoxycarbonyl)-2' phenylcyclopropyl]methyl]-2 ,6 -methano-3-benzazocin-8-ol, (1'S,2'R)6a and (+) cis-(1'R,2'S)-6,11-Dimethyl-1,2,3,4,5,6-hexahydro-3- [[2-(methoxycarbonyl)-2' phenylcyclopropyl]methyl]-2,6-methano-3-+ ++benzazocin-8 -ol, (1'R,2'S)6a are reported. Affinities of (1'S,2'R)6a and (1'R,2'S)6a were compared with those of the (-)-cis-diastereoisomers of MPCB(1), and of its p-Cl phenyl derivative CCB(2). The (+)-cis-N-normetazocine derivatives showed higher affinity for the sigma 1 sites, labeled with [3H]-(+)-pentazocine than the corresponding (-)-cis- analogs. In particular, compound (1'S,2'R)6a showed a Ki = 66.7 nM for sigma 1 receptor, associated with a good selectivity for sigma 1 with respect to kappa, mu, delta opioid receptors subtypes (Ki = > 1,000 nM). Analysis of the data seem to support the hypothesis that the (+)-cis-N-normetazocine nucleus posses a specific enantioselectivity for sigma 1 sites, when supporting bulkier N substituents functionalized with a carboxy ester group. PMID- 9372601 TI - Interactions of some PGHS-2 selective inhibitors with the PGHS-1: an automated docking study by BioDock. AB - The automated stochastic docking procedure BioDock has been applied to a series of inhibitors of PGH synthase, the key enzyme in the synthesis of eicosanoids from arachidonic acid. Some PGHS-2 selective inhibitors have been docked to the structure of the ovine PGHS-1 enzyme, as recently obtained by means of X-ray crystallographic analysis, in order to highlight possible structural bases for selectivity. PMID- 9372602 TI - Characterization of rheological and mucoadhesive properties of three grades of chitosan hydrochloride. AB - In the present study the rheological and mucoadhesive properties of three viscosity grades of a cationic polymer, chitosan, were investigated to assess the suitability of this polymer for gastroadhesive formulations. The influence of the pH, ionic strength and temperature of the hydration medium on the rheological properties was studied. The mucoadhesive performance was assessed in vitro by means of rheological synergism and tensile stress testing. A correlation was found between rheological synergism and tensile parameters (force of detachment and work of adhesion), which proves that both methods can correctly predict the mucoadhesive performance of the polymers examined. It was found that the interaction of chitosan with mucin decreases on increasing molecular weight. PMID- 9372603 TI - Evidence for multiple mechanisms of conceptual priming on implicit memory tests. AB - The authors examined effects of encoding manipulations on 4 conceptual-implicit memory tasks: word-cued association, category-cued association, category verification, and abstract/concrete classification. Study-phase conceptual elaboration enhanced priming for word-cued association with weakly associated words (Experiment 3), and for category-cued association with high- and low dominance exemplars (Experiments 4 and 5), but did not enhance priming for word cued association with strongly associated words (Experiments 1 and 2), for category verification with high- and low-dominance exemplars (Experiment 5), or for abstract/concrete classification (Experiment 7). Forms of priming that were unaffected by conceptual elaboration were not mediated by perceptual processes because they were unaffected by study-test modality changes (Experiments 6 and 8). The dissociative effects of conceptual elaboration on conceptual-implicit tasks suggest that at least 2 dissociable mechanisms mediate conceptual priming. PMID- 9372604 TI - Structural processing and implicit memory for possible and impossible figures. AB - Previous investigations have shown that participants are biased to respond "possible" to studied items when asked to decide whether objects could or could not exist in an object possibility test. The present study clarified and extended the concept of bias in implicit memory research in two ways. First, the authors showed that participants were biased to respond "possible" (rather than "impossible") on the object possibility test because structural processing was facilitated by prior study of possible, but not impossible, portions of objects. Second, the authors demonstrated that bias in this context was a form of, not an alternative to, implicit memory, by showing priming effects in response times when accuracy scores for studied and unstudied items were equated. The authors concluded by comparing proceduralist and memory-systems accounts of implicit memory effects and suggested that the two approaches could be seen as complementary rather than conflicting. PMID- 9372605 TI - Decision boundaries in one-dimensional categorization. AB - Decision-boundary theories of categorization are often difficult to distinguish from exemplar-based theories of categorization. The authors developed a version of the decision-boundary theory, called the single-cutoff model, that can be distinguished from the exemplar theory. The authors present 2 experiments that test this decision-boundary model. The results of both experiments point strongly to the absence of single cutoff in most participants, and no participant displayed use of the optimal boundary. The range of nonoptimal solutions shown by individual participants was accounted for by an exemplar-based adaptive-learning model. When combined with the results of previous research, this suggests that a comprehensive model of categorization must involve both rules and exemplars, and possibly other representations as well. PMID- 9372606 TI - Knowing that you don't know: metamemory and discourse processing. AB - In 6 experiments, the authors used a speeded question-answering task and a recognition task to examine how people know what they don't know. Extending work by S. Glucksberg and M. McCloskey (1981) to examine metamemory judgments about narratives, the authors asked participants to respond to 2 types of "don't know" questions. In certain conditions, readers were faster to respond "don't know" to implicit "don't know" questions (i.e., no information regarding the answers was provided) than to explicit "don't know" questions (i.e., narratives explicitly stated that something was unknown). The speed of responding to the implicit "don't know" questions was related to the familiarity of the question, which is consistent with claims that fast metacognitive judgments are based on a preliminary evaluation of the familiarity of a cue. This is a first step in integrating theories of metacognition and discourse processing. PMID- 9372607 TI - Enhanced metamemory at delays: why do judgments of learning improve over time? AB - Judgments of learning (JOLs) made after a 5-min delay are almost perfectly accurate: the "delayed-JOL effect" (T. O. Nelson & J. Dunlosky, 1991). The mechanisms underlying this phenomenon have been the subject of debate. This study examined the effects of delays and short-term memory (STM) distraction on memory and metamemory (JOLs). STM distraction (2.5-30 s) immediately following encoding increased both JOL accuracy and mean cued recall. However, JOLs made after longer delays (4-5 min) were even more accurate. In addition, making a JOL at longer delays improved cued-recall performance. Conditional probabilities of cued recall (given successful initial retrieval) also increased over time and with interference, indicating that delayed JOLs may alter what they assess. Finally, increased confidence was associated with shorter JOL latencies only at delays. The results are consistent with an accessibility view of metamemory (e.g., A. Koriat, 1993). PMID- 9372608 TI - Retrieval of lexical-syntactic features in tip-of-the-tongue states. AB - Italian speakers who signaled that they were in a tip-of-the-tongue (TOT) state were asked to recognize the grammatical gender and the initial and the final phonemes of the unavailable word. The proportions of gender and phoneme hits that occurred with "don't know" (DK) responses were adopted as baselines for chance level performance. Participants were more accurate in recognizing the grammatical gender and the initial but not the final phoneme of target words when they were in TOT than in DK states. The availability of gender in TOT states suggests the independence of syntactic from phonological information in lexical access. However, the retrieval of gender was far from perfect for TOT words, and it was no better than recognition of the initial phoneme. These results are problematic for the notion that the selection of a lemma is synonymous with the retrieval of the word's syntactic features. The implications of these results for the distinction between lemma and lexeme levels of representation in lexical access are discussed. PMID- 9372609 TI - Analogical transfer as guided by an abstraction process: the case of learning by doing in text editing. AB - The authors proposed that not only are the first attempts to solve a problem made by analogy but also that progress in learning can be guided by referring to more abstract knowledge, which affords new possibilities. Two experiments investigated this view in a situation of learning how to use a text editor. Experiments 1A to 1C identified the knowledge associated with 3 domains hypothesized as sources of transfer at increasing levels of abstraction (typewriting, writing in general, manipulating objects). Experiment 2 tested whether participants first use their knowledge about typewriting, then about writing in general, and then about manipulating objects. The data showed that the order of acquisition of text editor functions appeared to be strongly related to this hierarchy, supporting the idea that part of learning consists of discovering properties of objects by accessing increasingly general domains. PMID- 9372610 TI - Photodynamic destruction of Haemophilus parainfluenzae by endogenously produced porphyrins. AB - Bacterial resistance against antibiotic treatment is becoming an increasing problem in medicine. Therefore methods to destroy microorganisms by other means are being investigated, one of which is photodynamic therapy (PDT). It has already been shown that a variety of Gram-positive and Gram-negative bacteria can be killed in vitro by PDT using exogenous sensitizers. An alternative method of photosensitizing cells is to stimulate the production of endogenous sensitizers. The purpose of this study was to investigate the bactericidal efficacy of PDT for Haemophilus parainfluenzae with endogenously produced porphyrins, synthesized in the presence of delta-aminolaevulinic acid (delta-ALA). H. parainfluenzae incubated with increasing amounts of delta-ALA showed decreased survival after illumination with 630 nm light. No photodynamic effect on the bacterial viability was found when H. parainfluenzae was grown without added delta-ALA. H. influenzae, grown in the presence of delta-ALA, but not capable of synthesizing porphyrins from delta-ALA, was not affected by PDT. Of the range of incident wavelengths, 617 nm appeared to be the most efficient in killing the bacteria. Spectrophotometry of the bacterial porphyrins demonstrated that the maximum fluorescence occurred at approximately 617 nm, with a much lower peak around 680 nm. We conclude that a substantial killing of H. parainfluenzae by PDT in vitro after endogenous sensitization with delta-ALA can be achieved. PMID- 9372611 TI - UVB-induced photodamage to phycobilisomes of Synechococcus sp. PCC 7942. AB - The effect of UVB irradiation on the phycobilisomes (PBSs) of Synechococcus sp. PCC 7942 cells was studied. The sucrose density-gradient-isolated PBSs from in vivo UVB-treated (280-320 nm) cells showed a strong decrease in beta-phycocyanin (beta PC) and alpha-phycocyanin (alpha PC) polypeptides, in addition to a decrease in the linker polypeptides LCM 75 (linker connecting the core to the thylakoid membranes), LR 33 (linker in the rod structure), LRC 31.5 (linker connecting the rod to the core) and LRC 29. In vitro UVB treatment of gradient isolated intact PBSs for 1 h had no effect on any of the constituent polypeptides, and only after 2 h was a degradation of LCM 75 and LR 33 and a decrease in beta PC evident. Further investigation of phycobiliproteins (4 h of UVB irradiation) using polyclonal antibody directed against purified whole PBSs revealed that, in vivo, there was a gradual decline in the levels of LCM 75, LR 33, LRC 31.5, LRC 29, beta PC and alpha PC. PMID- 9372612 TI - Increased cytotoxicity and phototoxicity in the methylene blue series via chromophore methylation. AB - The cytotoxic and photodynamic activities of the commercially-available biological stains methylene blue (MB), 1,9-dimethyl MB (Taylor's Blue) and a newly synthesised compound, 1-methyl MB, were measured against the murine mammary tumour cell line, EMT-6. Both 1-methyl MB and 1,9-dimethyl MB exhibited increased dark toxicity with concomitant higher phototoxicity compared to MB at a light dose of 7.2 J cm-2. While increasing the light dose as a function of the fluence rate increased the photocytotoxicity of MB, this had little effect on the methylated derivatives. In vitro chemical testing proved that successive methylation rendered the phenothiazinium chromophore both more resistant to reduction to its inactive leuco form, and also led to increased levels of singlet oxygen production, thus providing a possible explanation for the increased toxicities of the methylated derivatives. Comparisons are made with the benzo[a]phenothiazinium photosensitizer, EtNBS. PMID- 9372613 TI - Biomodulative effects induced by 805 nm laser light irradiation of normal and tumor cells. AB - The influence of light emitted from a diode laser centred at lambda = 805 nm was investigated on murine skeletal myotubes (C2), normal urothelial cells (HCV29), human squamous carcinoma cells of the gingival mucosa (ZMK) and urothelial carcinoma cells (J82) in a computer-controlled irradiation chamber. Cells were treated with varying fluences between 0 and 20 J cm-2. The response was tested by analysis of the mitotic index using single cell counting after Orcein staining and proliferation index based on BrdU incorporation during DNA synthesis. While the mitotic index of C2, HCV29 and J82 cells increased at a fluence of 4 J cm-2, irradiation with fluences of 20 J cm-2 resulted in a slight decrease. ZMK tumor cells showed a decrease of the mitotic index with both fluences. No significant differences could be determined when using irradiances between 10 mW cm-2 and 150 mW cm-2. The BrdU test after irradiation showed no significant effects compared to the controls in each cell line. PMID- 9372614 TI - Si(IV)-methoxyethylene-glycol-naphthalocyanine: synthesis and pharmacokinetic and photosensitizing properties in different tumour models. AB - A Si(IV)-naphthalocyanine bearing two methoxyethylenglycol axial ligands to the centrally coordinated metal ion (SiNc) was prepared by chemical synthesis and assayed for the phototherapeutic activity after administration in a Cremophor formulation to C57BI/6 mice bearing a subcutaneously transplanted Lewis lung carcinoma or B16 pigmented melanoma. Pharmacokinetic studies indicate that the maximal accumulation in the tumour occurs at 24 h after intraperitoneal injection of 0.5 mg kg-1 of SiNc, although the naphthalocyanine concentration in the Lewis lung carcinoma (0.70 microgram g-1) is significantly larger than that in the B16 pigmented melanoma (0.15 microgram g-1). This results in a higher selectivity of tumour targeting in the case of the lung carcinoma. Photodynamic therapy (782 nm, 370 mW cm-2, 360 J cm-2) at 24 h after SiNc injection causes an efficient tumour response for Lewis lung carcinoma (50% lower tumour diameter on day 19 post treatment as compared to untreated controls) while the pigmented melanoma shows only a minor response regarding the rate of tumour growth. PMID- 9372615 TI - Phototoxicity of some novel porphyrin hybrids against the human leukemic cell line TF-1. AB - Photodynamic induced cytotoxicity by porphyrin-DNA cross linker/intercalator hybrid diads and triads has been studied on the human leukemic cell line TF-1. Cells were incubated for 1 to 4 h with these new photosensitizers and irradiated with white light. Cell survival was assessed by the propidium iodide staining, using flow cytometry analysis. A comparison of the dark and light cell survival factor values suggests that irradiation has a significant effect on the toxicity at low concentrations for the porphyrin-chlorambucil diad and to a lesser extent at high concentrations for the porphyrin-acridone diad, the porphyrin-acridine diad and the porphyrin-cholic acid-chlorambucil triad. While the intrinsic antileukemic (via DNA cross-linking) activity of the chlorambucil moiety and the structural details may be responsible for the photoenhancement of the toxicity, the presence of acridine or acridone which are avid intercalators of DNA, is responsible for a similar effect seen for diads. PMID- 9372616 TI - Increased efficacy of in vitro Photofrin photosensitization of human oral squamous cell carcinoma by iron and ascorbate. AB - Photofrin, a photosensitizer used in the photodynamic therapy of cancer, selectively localizes in cellular membranes. Upon exposure to visible light, Photofrin produces singlet oxygen (1O2), which reacts with membrane polyunsaturated fatty acids forming lipid hydroperoxides. Transition metals, such as Fe2+, catalyze the production of cytotoxic free radicals from lipid hydroperoxides. Ascorbate reduces ferric to ferrous iron, further augmenting lipid peroxidation. Therefore, to increase the efficacy of Photofrin photosensitization, we added 20 microM ferrous sulfate and 100 microM ascorbic acid, in an aqueous layer over SCC-25 oral squamous cell carcinoma cells during in vitro illumination. In electron paramagnetic resonance spin trapping experiments, using POBN (alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone), we observed that the presence of this pro-oxidant combination greatly increases the production of membrane-derived lipid free radicals. The effect was time dependent but only partially concentration dependent. Trypan blue dye exclusion demonstrated that this increase in lipid radical formation correlated with cytotoxicity. These observations support the hypothesis that Photofrin photosensitization leads to lipid hydroperoxide formation, which increases the cell's susceptibility to iron-induced Fenton chemistry. The resulting free radical-mediated lipid peroxidation results in cell death. From these data we hypothesize that the efficacy of photodynamic therapy of superficial cancer might be increased by the topical application of the pro-oxidant combination of iron and ascorbate. Furthermore, their use will probably allow lower doses of Photofrin without compromising antitumor effect. PMID- 9372617 TI - Fluorescence energy transfer-sensitized photobleaching of a fluorescent label as a tool to study donor-acceptor distance distributions and dynamics in protein assemblies: studies of a complex of biotinylated IgM with streptavidin and aggregates of concanavalin A. AB - A photokinetic method of detection of fluorescence resonance energy transfer (FRET) between special fluorescent labels is applied to study time-averaged spatial distribution of labeled proteins in protein assemblies. Prolonged irradiation of a sample at the absorption maximum of the energy donor label initiates FRET-sensitized fluorescence photobleaching of the energy acceptor label, which was monitored by steady-state fluorimetric measurements. Kinetics of the acceptor photobleaching and kinetics of decreasing the efficiency of FRET from donors to unbleached acceptors were determined. The FRET efficiency was found from measuring sensitization of acceptor fluorescence. Analysis of the photokinetic data permits to estimate the time-averaged distribution of acceptors on donor-acceptor distances in the range of characteristic distances of FRET. Dynamic processes influencing donor-acceptor distances can be also investigated by the method. Application of the method is demonstrated by the studies of a complex of biotinylated IgM with streptavidin and aggregates composed of concanavalin A and sodium dodecyl sulphate. A new thiadicarbocyanine dye was used as the acceptor label, R-phycoerythrin and tetramethylrhodamine isothio-cyanate were the donor labels. In the IgM-streptavidin complex, 16% of acceptors most contributed to FRET provided 90% of FRET efficiency, whereas acceptors made about the same time-averaged contribution to FRET in the concanavalin A aggregates. PMID- 9372618 TI - Regulation of copper/zinc and manganese superoxide dismutase by UVB irradiation, oxidative stress and cytokines. AB - We have examined the effects of UVB irradiation, oxidative stress and cytokines on the antioxidant enzymes copper/zinc and manganese superoxide dismutase (CuZnSOD and MnSOD) in HeLa cells. A single dose of UVB irradiation regulated dose-dependently the expression of the 4 kb transcript of MnSOD although it did not have any significant effect on MnSOD enzymatic activity. In contrast, UVB irradiation reduced both the enzymatic activity and the expression of the 0.7 and 0.9 kb mRNA transcripts of CuZnSOD. The cytokines TNF-alpha (1 ng ml-1 and 10 ng ml-1) and IL-6 (100 U ml-1) induced MnSOD activity, and TNF-alpha also upregulated MnSOD mRNA expression. Interestingly, genistein, a soy isoflavone and a tyrosine kinase inhibitor, was able to inhibit the induction of Mn-SOD activity and mRNA expression by TNF-alpha. Enzymatic CuZnSOD activity was depressed by a high dose of H2O2 while IL-6 or TNF-alpha had no effect on CuZnSOD activity. Our results demonstrate that, in addition to enzyme activity level, UVB irradiation can regulate the superoxide dismutases at the mRNA level. We also suggest that UVB irradiation, oxidative stress and cytokines regulate differentially CuZnSOD and MnSOD, and that the activities and expression of these antioxidant enzymes are controlled by distinct mechanisms. PMID- 9372619 TI - Biological effects of helium-neon (He-Ne) laser irradiation on acrosome reaction in bull sperm cells. AB - The purpose of this study was to determine the effect of He-Ne laser irradiation (632.8 nm, 10 mW) on the induction of acrosome reaction and mortality in bull sperm cells in comparison with two important capacitation agents; calcium and heparin. Frozen-thawed bull sperm cells were washed in percoll gradient and suspended at a concentration of 1 x 10(6) ml-1 in sp-TALP medium, capacitated in the presence of 2 mM CaCl2, 10 micrograms ml-1 heparin, or irradiated at fluences from 2 to 16 J cm-2, and incubated for 0, 30, 60 and 90 minutes. At the end of the incubation period, the percentage of sperm that were acrosome-reacted and dead was determined. The results obtained indicated that laser irradiation at all fluences produced a significant increase (p < 0.001) in the percentage of sperm cells that were acrosome reacted, and a significant decrease (p < 0.001) in the percentage of dead sperm at 90 minutes of incubation in comparison to other capacitation agents and the control group. The percentage of sperm cells with acrosome reaction was increased with increasing fluences of laser irradiation and time of incubation. It is conclude that the application of He-Ne laser irradiation at fluences from 2 to 16 J cm-2 induced the acrosome reaction and decreased the sperm mortality percentage in vitro of bull sperm cells. PMID- 9372621 TI - Targeting of the tumor microcirculation by photodynamic therapy with a synthetic porphycene. AB - 9-acetoxy-2,7,12,17-tetrakis-(beta-methoxyethyl)-porphycene (ATMPn) is a chemically pure substance with fast pharmacokinetics and superior photodynamic properties in vitro as compared to Photofrin. In this study the pharmacokinetics, photodynamic efficacy and tissue localization of ATMPn were investigated in vivo. Amelanotic melanomas (A-Mel-3) were implanted in dorsal skin fold chambers fitted to Syrian Golden hamsters. Fluorescence kinetics of ATMPn (1.4 mumol kg-1 b.w.i.v.; n = 8) were monitored by intravital microscopy. Quantitative measurements of fluorescence intensity were carried out by digital image analysis. For tumor growth studies 1.4 mumol kg-1 was injected 24 h (n = 3), 3 h (n = 3), 1 min (n = 6) and 2.8 mumol kg-1 1 min (n = 6) before PDT (Laser (630 nm) or lamp (600-750 nm), 100 mW cm-2, 100 J cm-2). Tumor volume was measured for 28 d. Solid tumors (n = 3) were excised 1 min after injection of ATMPn (2.8 mumol kg-1) and cryostat sections (20 mm) were analyzed by confocal laser scanning microscopy (CLSM) for tissue localization of the dye. Maximal fluorescence (mean +/- S.E.) arose in the tumor (94 +/- 7%) and surrounding host tissue (67 +/- 5%) 30 s post injection followed by a rapid decrease. Hardly any fluorescence was detectable 12 h after administration. Only PDT 1 min after injection of ATMPn was effective yielding 3/6 complete remissions (2.8 mmol kg-1, laser) and 6/6 complete remissions (2.8 mumol kg-1, lamp), respectively. One minute after injection the dye is primarily localized in the vascular wall of normal and tumor vessels as shown by CLSM. PDT at a time, when the dye is localized primarily in the tumor microcirculation, exhibits the best tumor killing effects showing that vascular targeting is effective in treating solid malignant tumors. ATMPn in liposomes makes administration and light irradiation in one session possible due to its fast pharmacokinetics. Thus, using ATMPn as a photosensitizer may provide more flexibility to perform PDT after surgical exploration and debulking as adjuvant therapy. PMID- 9372620 TI - RNA-protein cross-links induced by sensitization with a pyrroloquinolinone derivative, a furocoumarin analogue. AB - The capacity of 2,6-dimethyl-9-methoxy-4H-pyrrolo [3,2,1-ij] quinolin-4-one (PQ), a furocoumarin analogue, of inhibiting protein synthesis in Ehrlich cells upon UVA irradiation was investigated. Using 8-methoxypsoralen (8-MOP) as a reference, we observed that in our short-term test the block of RNA synthesis do not affect protein synthesis, which is driven by pre-synthesised molecules of m-RNA; actually 8-MOP, studied at 100 microM concentration, practically abolished RNA synthesis without affecting significantly protein synthesis. Studying PQ sensitization in HL60 cells by alkaline elution and protein precipitation, the formation of covalent RNA-protein cross-links was observed. 8-MOP, assayed in severe experimental conditions, induced only moderate amounts of such lesion. On the basis of the data obtained in experiments carried out using various scavengers or exposing cells to UVA light in a nitrogen atmosphere, this damage appeared to be due to singlet oxygen formation, which is generated by PQ to a large extent. These results are consistent with the data obtained by H. Singh and J.A. Vadasz (Singlet oxygen: a major reactive species in the furocoumarin photosensitized inactivation of E.coli ribosomes, Photochem. Photobiol., 28 (1978) 539-545) on E.coli ribosomes. The lower activity we observed with 8-MOP might be attributed to a different sensitivity of whole mammalian cells in comparison with isolated ribosomes. PMID- 9372622 TI - Pharmacokinetics of 5-aminolevulinic acid-induced protoporphyrin IX in skin and blood. AB - The fluorescence and photosensitivity of endogenously synthesized protoporphyrin IX (PPIX) is increasingly used for the diagnosis and treatment of malignant and certain non-malignant diseases. A selective accumulation of PPIX can be induced by application of 5-aminolevulinic acid (5-ALA), which is a precursor of PPIX in the cellular biosynthetic pathway of heme. The purpose of this study was to monitor the in vivo accumulation of PPIX in different locations of the skin after oral ingestion and to determine the pharmacokinetics of 5-ALA and PPIX in human blood plasma for various routes of application. At the same time we wanted to achieve an optimal treatment scheme but also study possible side-effects of 5-ALA administration. After oral application of 5-ALA in a concentration of 40 mg kg-1 body weight, the fluorescence intensities of PPIX in the skin showed maxima between 6.5 and 9.8 h depending on the location and decreased to values lower than 5% related to the maximum after a mean time of about 40 h. The measured absolute intensities of PPIX fluorescence varied strongly between different patients and different locations on one patient. In the plasma of blood samples, PPIX could be detected via its fluorescence for all studied routes of application with the exception of the ointment, where PPIX levels were below the detection limit of 1 microgram l-1. The highest mean concentration of 742 micrograms l-1 PPIX in the plasma was measured 6.7 h after oral application. For inhalation of 5 ALA, a mean maximum concentration of 12 micrograms l-1 could be detected 4.1 h after application, for intravesical instillation, the mean maximum concentration was found to be 1 microgram l-1 2.9 h after application. The kinetics of 5-ALA in the plasma peaked much earlier with a maximum concentration of 32 mg l-1 about 30 min. after oral administration. The 5-ALA levels did not exceed normal reference values after topical application. The results of our experiments suggest that for a systemic application of 5-ALA side-effects in sensitive patients cannot be excluded. PMID- 9372623 TI - Reproductive health in humans and wildlife: are adverse trends associated with environmental chemical exposure? AB - In recent years, evidence from disparate observations has indicated adverse changes in the reproductive health and fecundity of animals and humans. In humans, there is strong evidence for such trends in the incidences of testicular and female breast cancer, and concern has also been expressed regarding semen quality, cryptorchidism, hypospadias and polycystic ovaries. Laboratory studies have indicated that some chemicals in the environment, both natural and synthetic, have the potential to disrupt the endocrine system and that these could, at least theoretically, be partly responsible for the observed changes. Chemicals thus identified include the naturally occurring steroid hormones, phyto and myco-estrogens, and anthropogenic chemicals such as synthetic hormones, organotins, organochlorine pesticides, polychlorinated biphenyls, dioxins, alkylphenol polyethoxylates, phthalates and bisphenol-A. While there is no direct evidence from human studies to confirm a causal link between exposure and effect, concern exists and is strengthened by reports of adverse reproductive and developmental effects in wildlife, possibly mediated via endocrine disruptive pathways. The development of imposex in neogastropod molluscs exposed to tributyltin has been attributed to such a mechanism and in wild populations of fish, alligators and birds, instances of masculinisation or feminisation in polluted areas have been noted. Among mammals, disturbed fertility of Florida panthers and some marine species has also been reported. A concentrated research and monitoring programme is required to clarify the nature and extent of effects on reproductive health in humans and wildlife, and to assess human and wildlife exposure to relevant naturally occurring or anthropogenic endocrine disrupting substances. This will enable a more robust evaluation of the contribution that environmental chemical exposure may have on adverse trends in the reproductive health of humans and wildlife. PMID- 9372624 TI - Identification of historical lead sources in roof dusts and recent lake sediments from an industrialized area: indications from lead isotopes. AB - X-ray fluorescence and stable lead (Pb) isotopic analyses have been undertaken on dusts, known from microscopic investigation to contain significant quantities of industrially- and urban-derived particulate matter, present in the roof cavities of houses in the Illawarra region (N.S.W., Australia), with the objective of examining the historic record of Pb pollution. All investigated houses contained in excess of 250 micrograms g-1 Pb, with dwellings close to a copper smelter, in a large industrial complex including a major steelworks, containing higher (> 2500 micrograms g-1) Pb concentrations. The isotopic composition in the dusts, expressed here as 206Pb/204Pb, is relatively constant at 17.0, irrespective of dwelling age or distance from the industrial complex. Contamination of the dusts by Pb sourced from paint cannot explain the isotopic uniformity of the dust samples. Isotopic modelling indicates that the dusts contain Pb derived from the copper smelter, gasoline-air Pb and a minor contribution from coal-utilising sources. Lead loading was also investigated in the adjacent lagoon, which acts as a natural sink for particulate matter in the Illawarra region. Isotopic data and modelling indicate that one natural and four anthropogenic sources contribute to the Pb burden of this lagoon. The natural source consists of Permian rocks cropping out in the catchment area which have a 206Pb/204Pb of approximately 18.7. The suggested anthropogenic sources are an old disbanded base-metal (Pb) smelter (206Pb/204Pb approximately 16.2-16.3), the copper smelter (206Pb/204Pb approximately 17.9), gasoline-air derived Pb (206Pb/204Pb approximately 16.4 16.5) and industries utilising coal, for example the recently closed thermal coal fired power station (206Pb/204Pb approximately 18.9). The relative contributions of the base-metal (mainly lead) smelter and gasoline-air Pb in the sediment can only be partly assessed due to the isotopic similarity of these sources. Likewise the natural background and coal source (e.g. power station) contributions can only be estimated from historical data. Age estimations for sediment cores, using 137Cs, provide some control on these assessments. Near surface sediments in the lagoon have a relatively constant 206Pb/204Pb of 17.6-17.7, irrespective of sample location. Isotopic calculations, together with records of particulate matter pollution emissions, indicate a link between the Pb in roof dusts (206Pb/204Pb approximately 17.0) and Pb contamination of the near surface (upper 20 cm) lagoonal sediments via a homogeneous, non-unique source of lead whose isotopic composition closely matches that of the dusts. Over the last 5 decades, atmospheric fallout of Pb-bearing particulate matter appears to have been the dominant pathway for addition of Pb to the lagoon and dwellings in the Illawarra region. PMID- 9372625 TI - Vaporizing characteristics of mixed-solvents in indoor environment. AB - Vapor pressure is usually used for predicting the phase-transfer of solvent. Combining it with molar ratio of component in liquid phase, airborne concentration of solvent is theoretically calculated. It's worthwhile to clarify if it is true in real environment. This study examines the vaporizing profile of xylol (commercial xylene) manipulation in a paint-manufacturing plant. Twelve workers equipped with 3M 3500 passive organic vapor monitors were sampled for 3 days. Solvents were analyzed by a gas chromatograph with flame ionization detector. According to the results, concentration ratio of airborne ethylbenzene and xylene is 0.384, though the ratio is 1.0 in the liquid phase and both solvents have similar vapor pressures. This finding suggests that predicting solvent's airborne concentration by liquid composition and vapor pressure may distort the air pollution profile. Moreover, high temperature increased airborne concentration significantly. PMID- 9372626 TI - Mutagens and carcinogens in size-classified air particulates of a northern Italian town. AB - This research was designed to examine the presence of mutagenic/carcinogenic compounds in urban airborne particulate matter in relation to particles aerodynamic size. Inhalable (< 10 microns) airborne particulate (PM-10) was collected at a low traffic site in an industrialized Northern Italian town, using a high volume sampler equipped with a cascade impactor for particles fractionation. The organic extracts of different fractions were examined for mutagenicity in Salmonella typhimurium strains TA98 and TA98/1,8-DNP6 using the microsuspension procedure, and for polycyclic aromatic hydrocarbons (PAHs) content by gas chromatography. Size fractionated particles were also analysed for heavy metals (Fe, Mn, Zn, Pb, Cu, Cd, Cr, Ni, V) using plasma spectrophotometry. The results of mutagenicity and chemical analyses indicate that, at the site investigated, inhalable particulate was largely made of fine (< 0.5 micron) particles, which accounted for most of PAHs and mutagenicity. A similar pattern of distribution was found for heavy metals, which were relatively more abundant in small (< 1.5 microns) particles compared to coarser ones. PMID- 9372629 TI - Determination of lead and cadmium in food and blood by inductively coupled plasma mass spectrometry: a comparison with graphite furnace atomic absorption spectrometry. AB - To compare inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectometry (GF-AAS) as the method for determining lead and cadmium in the human diet and blood, 418 diet homogenate samples and the same number of blood samples were collected from Chinese and Japanese women and were analyzed by the two methods. The results showed that our ICP-MS method is precise and accurate, being comparable to the GF-AAS method established previously. The ICP-MS method is simple and fast spending only one-tenth of the time necessary for GF-AAS and allows simultaneous analyses of lead and cadmium with low detection limits. When applied to actual sample analysis, however, ICP-MS results tend to be 10-20% lower than GF-AAS results in the analysis of lead in the diet and blood and cadmium in blood. This is possibly due to some interference in ICP MS and matrix of samples. As the ICP-MS results could be mathematically corrected to be equivalent to the GF-AAS results, we conclude that this ICP-MS method can be used as a routine analytical method for the determination of lead and cadmium in human diet and blood samples. PMID- 9372627 TI - Serum concentration and dietary intake of Zn in healthy institutionalized elderly subjects. AB - We determined the serum concentrations and dietary intake of zinc, as indicators of Zn status, in 44 healthy institutionalized elderly subjects in Granada (Spain) (mean age 81.4 +/- 7.9 years). Determination of Zn in serum was carried out by electrothermal atomic absorption spectrophotometry. Serum samples had a mean Zn concentration of 10.49 +/- 3.5 mumol/1. No significant differences were found in the serum levels of Zn as regards the sex of the subjects. However, concerning Zn intake, determined by a 7-day weighted food record, a significant statistical difference (P < 0.001) was found between men and women, with mean values of 10.01 +/- 1.76 mg/day and 7.33 +/- 1.33 mg/day, respectively. Application of regression analysis to the serum concentration of Zn and other nutritional parameters shows a statistically significant correlation (P < 0.05) between serum levels of Zn and the body mass index. The lack of statistical correlation between the serum concentration of zinc and its intake indicates that this index cannot be used as an indicator of zinc status in the elderly. PMID- 9372628 TI - Secondary organic aerosols: formation potential and ambient data. AB - Organic aerosols comprise a significant fraction of the total atmospheric particle loading and are associated with radiative forcing and health impacts. Ambient organic aerosol concentrations contain both a primary and secondary component. Herein, fractional aerosol coefficients (FAC) are used in conjunction with measurements of volatile organic compounds (VOC) to predict the formation potential of secondary organic aerosols (SOA) in the Lower Fraser Valley (LFV) of British Columbia. The predicted concentrations of SOA show reasonable accord with ambient aerosol measurements and indicate considerable seasonal variability in SOA potential. Particulate carbon contributes only approx. 3% of total carbon concentrations in the LFV, and it is shown that variability in total carbon concentrations is significantly larger than variability in gas/particle partitioning. PMID- 9372630 TI - Trace element concentrations in blood and hair of young apprentices of a technical-professional school. AB - The concentrations of total Fe, Cu, Mn, Zn, Pb, Cr, Ni and Ca in the whole blood of young male apprentices of a technical-professional school, who are exposed to low doses of fumes from manual metal arc welding of mild steel, were monitored over their 2 years of apprenticeship in order to evaluate the influence of occupational exposure on biological metal levels. The results were compared with those from a control group of the same sex and age and living in the same geographic area. For comparison, monitoring of the same metal levels in the hair of both groups of individuals were also carried out. In the apprentices, the mean metal concentrations in blood at the end of the study were statistically significantly higher for Cu, lower for Fe and Mn and similar for the remaining metals. The levels of Fe significantly decreased whereas the levels of Cu were significantly increased during the study. A systematic influence of the exposure period on the levels of Mn was not observed. All the metal concentrations measured in the blood and hair of both apprentices and controls fell in the very large range of published reference levels. Seasonal variation (higher levels in the summer) of the hair metal concentrations were observed for Mn, Cu, Pb, Ni, Zn and Ca. PMID- 9372632 TI - Intake of methyl mercury by the population of Mumbai, India. AB - Reversed phase high performance liquid chromatography (HPLC) with ultra violet detection (UV) was optimised for separation and quantification of methyl mercury in coastal sediment and fish samples. The extraction efficiency of methyl mercury from sediment and biological samples was found to be 56% with a detection limit of 0.5 ng for a 200 microliters sample volume. The concentrations of methyl mercury and the relative fractions with respect to total mercury were distinctly lower, 5.9-65.5 ng/g (3-8%) in sediment compared to biological samples, 20.4 344.5 ng/g dry wt. (33-97%). The daily intake of methyl mercury by the Mumbai population through marine food is about 0.5 microgram forming 62% of the total mercury intake from this route. PMID- 9372631 TI - Can microorganisms convert antimony trioxide or potassium antimonyl tartrate to methylated stibines? AB - No evidence could be found for the production, in culture, of methylated antimony compounds from water-insoluble or soluble antimony derivatives by the aerobes, Scopulariopsis brevicaulis or Bacillus sp. or by anaerobes associated with cot mattress materials. The study does not support the hypothesis that volatile organoantimony compounds are a cause of cot deaths. Anaerobic cultures from a polluted pond generated trimethylstibine from potassium antimonyl tartrate. PMID- 9372633 TI - Maintenance of elevated lead levels in drinking water from occasional use and potential impact on blood leads in children. AB - The variation in lead concentration was measured by thermal ionisation mass spectrometry isotope dilution in household tap water throughout the day when the plumbing system was not fully flushed. After collection of an initial 125-ml water sample containing 119 micrograms/l and a 2-l sample, 125-ml samples were collected at hourly intervals for 8 h. The concentrations in the hourly samples remained in the range 35-52 micrograms/l compared with 1.7 micrograms/l for fully flushed water. High precision lead isotopic measurements showed that approximately 50% of the lead in these water samples derives from the tap 'housing' compared with the overall household system. A health risk assessment was performed employing the US Environmental Protection Agency Integrated Exposure Uptake Biokinetic Model. Predicted blood lead levels in infants only exceeded the 'levels of concern' of 10 micrograms/dl when 100% of the water consumed contained 100 micrograms Pb/1. It would appear that unless the infant consumed 100% of first flush water at lead concentrations of approximately 100 micrograms/l, the blood lead would not exceed the recommended 'level of concern'. However, if more than 0.51 was consumed in drinks and formulae using first flush water, then the blood lead could easily exceed the recommended level. Likewise, a pregnant mother could be at risk of consuming considerably more than the 0.51/day first flush water of the concentrations measured, or throughout the day, if the system were not fully flushed. PMID- 9372635 TI - Becoming a young parent: a longitudinal study of associated factors. AB - Teenage fertility rates in the UK are amongst the highest in Europe and have not altered significantly in the last 15 years, but the proportion of births outside marriage has risen rapidly. In this study we used longitudinal data from the National Child Development Study (NCDS) to investigate the social, economic and educational backgrounds of young parents. The analysis showed there to be striking variations in the probabilities of becoming young parents but not with respect to whether the child was born within or outside marriage. Young mothers and fathers were more likely to come from economically disadvantaged families and to have lower educational attainment. Teenage mothers were more likely to have mothers who had a child in her teens and were more likely to have exhibited higher levels of emotional problems particularly in adolescence. Young women whose educational attainment scores deteriorated between childhood and adolescence had particularly high probabilities of becoming young mothers. For some teenage motherhood was unintended and the result of unprotected intercourse whilst other men and women who subsequently become young parents had expressed a preference for early parenthood whilst still at school. PMID- 9372634 TI - Household and labour market change: implications for the growth of inequality in Britain. AB - The paper examines the relationships between population and household change, on the one hand, and labour market/employment change, on the other, and considers how these relationships have contributed to the growth of inequality. The perspective of the paper is sociological, although much of the work done in these areas has been carried out by demographers and economists. Areas where sociological research remains to be done are highlighted. Developments in patterns of fertility and in households are linked to the growth of individualism and to changes in the labour market, and shown to be implicated jointly in the marked growth of inequality in Britain. The paper argues that future research must link households and labour markets, and work towards understanding emerging new relationships between working and private lives, between living arrangements and labour supply, and between individual freedom and social integration. PMID- 9372636 TI - Inequality, economic growth and social mobility. AB - This paper develops a model of intergenerational mobility and intragenerational inequality that allows us to explore the relationship between economic growth and social mobility. The model is used to analyse the neo-liberal theory of stratification and to assess the consequences of some of the criticisms that have been made of it. In particular, the intergenerational transmission of wealth and privilege, and the existence of ethnic, gender and other forms of ascriptive disadvantage, reduce economic efficiency, although they do not always diminish the extent of social mobility. Furthermore, excessive intragenerational inequality may inhibit, rather than encourage, economic growth. We show that there is no necessary link between rates of social mobility and levels of economic growth. This, we suggest, provides an explanation of why rates of social mobility show very little cross-national variation and display no very evident trend over time towards greater societal openness. PMID- 9372637 TI - Political ideology and popular beliefs about class and opportunity: evidence from a survey experiment. AB - This paper examines popular understanding of class inequalities in opportunity using an experimental approach to assess implicit as well as explicit comprehension. Three competing representations of popular beliefs are compared: a 'class inequality' model, implying widespread belief in class-related inequalities of opportunity; a 'meritocratic' view of achievement, in which emphasis is placed on individual responsibility; and an 'ideological polarization' model, which assumes that beliefs emphasizing class inequality or merit vary with left-right ideology. Predictions derived from these ideas are tested using a national survey with an experimental design, in which respondents are presented with vignettes designed to elicit their beliefs as to how and why people from different class backgrounds obtain middle-class or working-class occupations. As predicted by the class inequality model, there is clear evidence of the impact of tacit assumptions about class structured inequality of opportunity on expectations, judgments of responsibility and explanations of occupational attainment. Even among right-wing respondents, who are more likely to endorse the rhetoric of individual responsibility, there remains an implicit awareness of social class influences on life-chances, suggesting the pervasive presence of these beliefs in popular understanding of social processes. PMID- 9372638 TI - 'A way of struggle': reformations and affirmations of E. P. Thompson's class analysis in the light of postmodern theories of language. AB - This paper is an analysis of the role of language in historical class formation in light of the recent developments in postmodern social theory and historiography. Revisionists from within this perspective have questioned if not abandoned E. P. Thompson's class struggle analysis, arguing that he fails to account for the constitutive character of language in the construction of collective identities. They oppose his account of the making of the English working class with alternative histories emphasizing populist and other non-class identities. Drawing on the Bakhtin Circle of literary studies, and returning to Thompson's own writings, I argue that we can incorporate language into class struggle analysis as a critical mediating force. I maintain that class struggle occurs largely within a hegemonic discursive formation, and that class consciousness and identity thus in part are formed through counter-hegemonic strategies of resistance to ideological domination. To illustrate this theory I analyse the role of language in the class struggles of the silk weavers of the Spitalfields district in London in the 1820s. I analyse how the silk weavers articulated a class consciousness through their counter-hegemonic struggles with the large capitalists and the language of political economy. PMID- 9372639 TI - Politics and the struggle to define: a discourse analysis of the framing strategies of competing actors in a 'new' participatory forum. AB - On account of the current wave of environmental consciousness, the state is adapting to the phenomena of systems of negotiations outside of the traditional institutional framework on environmental issues in an attempt to preserve cultural support. However recent experiments in discursive democracy have proven to be a modality for the transmission of productivist culture and for the reassertion of corporatist tendencies. This interpretation finds support here primarily through a discourse analysis based on a three-dimensional framework. The analysis begins by examining the structure of discursive formations of various participating actors at the Irish National Recycling Conference in 1993, and explores the ways in which actors struggled at the symbolic level to define the rules constitutive of this space of play. It argues from the perspective of discourse as social practice and justifies this approach by assessing the degree of synchronization between collective actors' systems of discursivity and the socially structured institutional sites within which they are embedded. Finally, by examining the position of this field vis-a-vis the field of political power, this research will show how broader relations of domination and traditional power asymmetries came to be reasserted in a 'new' participatory arrangement. PMID- 9372640 TI - Did British society change character in the 1920s or the 1980s. AB - This is a response to Runciman's reply to my critique of his 1993 article. I argue that although the First World War brought about many changes in British society, it did not initiate a new stage in its development, for these changes were largely an acceleration of existing tendencies. Runciman's argument that the similarities between the 1930s and the 1980s show that British capitalism was essentially the same in both periods does not allow for the different directions in which British society was moving in the 1930s and in the 1980s. His treatment of the 1980s changes as another phase in the political cycle fails to grasp what was new about the 1980s or locate these changes in their wider economic and global context. PMID- 9372641 TI - Chemical and physical parameters of tears relevant for the design of ocular drug delivery formulations. AB - This paper provides a summary of the most important chemical and physical parameters of tears that can help the formulator in the development of new ocular formulations and in the conception of innovative ophthalmic delivery approaches. For each physiological parameter, the relevance in ocular drug delivery is discussed in detail and the analytical tools that are used for the determination of these parameters are described and summarized. The aim of this review is also to give a description of the main analytical techniques available in ophthalmology that can be used for pharmacokinetic studies of active compounds. The importance of tear sampling techniques used in the determination of the parameters is also discussed. PMID- 9372642 TI - Promotion of oral insulin absorption in diabetic rabbits using pH-dependent coated capsules containing sodium cholate. AB - The hypoglycemic effect of oral insulin (40 U) capsules coated with a pH dependent soluble polymer (Eudragit S100) and containing various doses of sodium cholate (20, 50, 100 mg) was studied in alloxan-hyperglycemic rabbits and compared with that of s.c. insulin injection (20 U). Sodium cholate (20 and 50 mg/capsule) produced a dose-related enhancement of an insulin-induced decrease in the blood glucose level. Insulin capsules containing sodium cholate (50 mg/capsule) produced a steady reduction of the blood glucose level reaching 69% of the initial values (P < 0.01) by 3 h and 48% (P < 0.001) by 5 h after administration. This capsule produced an AUC0-5 h of 125 +/- 14.8 mg.h/dl with relative hypoglycemia (R.H.) of 25.8% compared with insulin s.c. The capsules containing sodium cholate (100 mg), however, did not significantly (P > 0.05) improve the hypoglycemic effect of insulin more than the smaller dose (50 mg/capsule) producing an AUC and R.H. of 135 +/- 12.3 mg.h/dl and 27.9%, respectively. The capsule coated with Eudragit S100 and containing insulin mixed with sodium cholate seems to be a promising formulation to overcome the unavailability of oral insulin. PMID- 9372643 TI - Haematological and biochemical alterations in leprosy patients already treated with dapsone and MDT. AB - Dapsone (DDS) is useful in the treatment of a number of inflammatory conditions which are characterized by neutrophil infiltration. It is the drug of choice for the treatment of leprosy and prophylaxis of malaria. Haematological side effects of methaemoglobinaemia and haemolysis have been long recognized. However, the frequency and severity of these side effects in patients already treated with DDS as a single drug or as part of a multidrug therapy (MDT) have not been well documented. We report herein an investigation of the effect of dapsone long-term treatment on the haematological and biochemical alterations in leprosy patients undergoing dapsone as a single drug (DDS group) or as part of a multidrug therapy in combination with rifampin and clofazimine (MDT group). Methaemoglobinaemia and haemolytic anaemia were the principal side effects observed. Reticulocytes were found to be elevated (> 1.5%) in 90% of the patients. Heinz bodies were also detected (6.6% of the patients). The osmotic fragility test showed a reduction in cell resistance and in the evaluation of white cells a severe eosinophilia was found. Hepatic, pancreatic and renal evaluation by the determination of biochemical parameters showed rare and occasional changes of no apparent clinical significance. We conclude that haematological side effects of dapsone are significant even at doses currently used to treat leprosy (100 mg/day) and that rifampin and clofazimine do not increase the incidence of these effects during long-term treatment. PMID- 9372644 TI - Physicochemical properties and in vitro toxicity of cationic liposome cDNA complexes. AB - The purpose of this study was to elucidate the interaction of cationic liposomes and plasmid cDNA by examining their ultrastructure, zeta potential, stability in aqueous media and protection from DNaseI digestion; their potential for hemolysis and platelet aggregation was evaluated as it may serve as an in vitro toxicity screen. Liposomes consisting of N-[1-(2,3-dioleyloxy)propyl]-N,N,N trimethylammonium chloride (DOTMA) or 3 beta-[N-(N',N'-dimethylaminoethane) carbamoyl]-cholesterol (DC-Chol) and dioleylphosphatidylethanolamine (DOPE) were complexed with plasmid constructs of ovine prostaglandin G/H synthase (pCMV4-PGH) or human alpha 1-antitrypsin (pCMV4-AAT) at lipid:plasmid (L/P) ratios of 3:1-8:1 (w/w). The electron micrographs showed bead-like attachment of liposomes to cDNA and coating of plasmid strands. The zeta potential showed isoelectric points at L/P ratios of 3.5-4 (DOTMA/DOPE) and 5.5-6.5, corresponding to a pKa of 6.45 (DC Chol/DOPE). Liposome cDNA complexes were stable in water, saline and 5% dextrose for 48 h, but precipitated instantaneously in PBS. An increase in the L/P ratio corresponded with increased protection from DNaseI digestion. DOTMA/DOPE liposomes alone were highly hemolytic and DC-Chol/DOPE liposomes moderately hemolytic; hemolysis was abolished by cDNA complexation, with the exception of very high (> or = 7:1) L/P ratios. Both liposomes alone and cDNA complexes caused transient serum turbidity, while none caused platelet aggregation. It was concluded that current cationic lipid cDNA formulations are metastable and appear to have very little if any toxicity with respect to hemolytic potential and untoward interaction with other blood components. PMID- 9372645 TI - An investigation of the physical behaviour of moisture-activated mucoadhesive hydrogels upon contact with biological and non-biological substrates. AB - The physical behaviour of moisture-activated mucoadhesive hydrogels in contact with a Plexiglas plate or artificial mucin gels was investigated using an adapted tensile tester fitted with force and displacement transducers. Our study of the 'Plexiglas-hydrogel' interface showed that the intrinsic mechanical response of most poly(acrylic acid) polymers is quite different from that exhibited by cellulose derivatives. The former exert an attractive interaction towards the substrate in contrast to the latter where the interaction is essentially repulsive. The interfacial forces developed by pure mucin were closely related to those of poly(acrylic acid) polymers. Similar results were observed when the Plexiglas was replaced by artificial mucin gels. A correlation was found between the attractive force developed by poly(acrylic acid) hydrogels towards the inert substrate and their in vitro mucoadhesive joint strength. Therefore, a non specific physical interaction occurs during the initial adhesive process, whatever the nature of the substrate. Besides the water absorption capacity and swelling properties of the candidate materials, it seems that their initial mucoadhesiveness depends more on their mechanical response to hydration and less on the extent of molecular interactions at the adhesive interface. PMID- 9372646 TI - Goal of the treatment for sarcoidosis. Minimize harm for the patient. PMID- 9372647 TI - Treatment of progressive pulmonary sarcoidosis with cyclosporin A. A randomized controlled trial. AB - Conventional treatment of sarcoidosis is often only partially effective. We examined the effect of cyclosporin A (CsA) combined with prednisone for the treatment of sarcoidosis. Thirty-seven patients with biopsy-proven sarcoidosis were treated with either prednisone 20 mg/d in a prospectively tapered regimen (P) or with combination therapy consisting of prednisone 20 mg/d in a prospectively tapered regimen and cyclosporin A, 5 to 7 mg/kg/d (P-CsA) for up to 18 mo in an open-label randomized controlled trial. Evaluation was done at baseline and at 3, 9, and 18 mo of the degree of dyspnea, pulmonary function, chest radiographs, bronchoalveolar lavage (BAL), and adverse events. Criteria for a good therapeutic response, improvement, treatment failure, and relapse were defined. Thirty-seven patients were treated for at least 9 mo and 18 mo. Six patients in remission were included in an intention-to-treat-analysis at 18 mo. The groups did not differ significantly with respect to therapeutic response from baseline. A significant (p < 0.05) improvement was observed in dyspnea until 9 mo (P) and 18 mo (P-CsA), and in lung function until 9 mo (P) and 3 mo (P-CsA). BAL results showed a significant decrease in lymphocyte counts at 9 mo for the P group only (p < 0.05). More side effects were observed in the P-CsA group than in the P group, including elevation of the mean serum creatinine concentration at 3 and 9 mo (p < 0.05), and a doubling of the number of infections in this group. Relapse after an initially good therapeutic response occurred in two of nine patients in the P group and five of seven patients in the P-CsA group (p < 0.07). Although CsA may have theoretical benefits in the treatment of sarcoidosis, our results do not support its use in this disease. PMID- 9372648 TI - Release of RANTES, MIP-1 alpha, and MCP-1 into asthmatic airways following endobronchial allergen challenge. AB - We have investigated the presence of regulated on activation, normal T-cell expressed and probably secreted (RANTES), macrophage inflammatory peptide-1 alpha (MIP-1 alpha), and macrophage chemotactic peptide (MCP-1) in the bronchoalveolar lavage fluid (BALF) obtained from normal (n = 7) and stable asthmatic subjects (n = 8), and studied their kinetic release into asthmatic airways following endobronchial allergen challenge (n = 18). Measurements of RANTES, MIP-1 alpha, and MCP-1 in 10 times (10x) concentrated BALF showed that these three chemokines were present in both normal controls and stable asthmatic patients, but no significant difference between the two groups was found in the levels of the three chemokines. However, at 4 h after allergen challenge, BALF levels of RANTES, MIP-1 alpha, and MCP-1 were significantly increased in fluid obtained from the allergen-challenge site when compared with the saline-challenge control site (median: 175 pg/ml versus 11.5 pg/ml, 258 pg/ml versus 88 pg/ml, and 900 pg/ml versus 450 pg/ml, respectively). At 24 h, levels of the three chemokines returned to baseline values. To investigate whether cells in BALF obtained 4 h after allergen exposure release chemokines, they were cultured for 24 h. BALF cells from the allergen site released more RANTES and MCP-1 than those from the saline site, but released similar amounts of MIP-1 alpha. These findings suggest that RANTES, MIP-1 alpha, and MCP-1 may regulate cell trafficking in asthma in response to allergen exposure. PMID- 9372649 TI - Expression of interleukin-5 and granulocyte-macrophage colony-stimulating factor in aspirin-sensitive and non-aspirin-sensitive asthmatic airways. AB - Increased numbers of eosinophils and mast cells in the bronchial mucosa are characteristic features in subjects with aspirin-sensitive asthma. Interleukin-5 (IL-5) and granulocyte-macrophage colony-stimulating factor (GM-CSF) are involved in the activation, maturation, and perpetuation of survival of eosinophils. Immunohistochemical techniques were therefore used to study the expression of IL 5 and GM-CSF on frozen bronchial biopsies from 13 aspirin-sensitive asthmatic (ASA) and 8 non-ASA (NASA) subjects. Aspirin sensitivity was diagnosed by lysine aspirin inhalation provocation. ASA airways demonstrated a significant 2-fold increase in the total number of submucosal inflammatory cells expressing IL-5 (p = 0.03) and approximate 4- and 2-fold increases in the numbers of mast cells expressing IL-5 and GM-CSF (p = 0.02 and p = 0.04, respectively). There was also a 4-fold increase in the number of eosinophils expressing IL-5 (p = 0.004). These results suggest a central role for the mast cell and eosinophil in regulation of the inflammatory cell infiltrate of ASA airways by secretion of the hemopoietic cytokines IL-5 and GM-CSF. PMID- 9372651 TI - HLA class II genes in soybean epidemic asthma patients. AB - From 1981 to 1987, 26 outbreaks of asthma caused by the inhalation of soybean dust, affecting a total of 688 individuals, were detected in Barcelona, Spain. Because only a small proportion of asthmatic individuals living in Barcelona expressed the epidemic phenotype, it is hypothesized that a genetically determined human leukocyte antigen (HLA) Class II factor could have played a role in the susceptible individuals. Accordingly, we studied the distribution of both HLA-DR and HLA-DQ in soybean epidemic asthmatic patients. An analysis of the HLA DR and HLA-DQ genes for genetic polymorphisms of the beta 1 chain was done with the polymerase chain reaction (PCR) in 78 soybean epidemic asthma patients, and the findings were compared with those for 67 nonepidemic asthmatic individuals and 168 individuals from the general population. An allelic disequilibrium could be established; the risk of epidemic asthma was particularly associated with the DRB1*13 gene (p value corrected for multiple comparisons < 0.02). The association observed for the DRB1*13 gene was stronger in individuals in the lowest tertile for total IgE, with an estimated risk with a 95% confidence interval (CI), of 14.5 (1.6 to 130.8). The combination of two genes from among the DRB1*05-05, DRB1*05-06, and DRB1*06-06 genes was present in epidemic asthmatic subjects only. No association with an HLA-DQB1 allele could be observed. Genetic predisposition could contribute to the response of some asthmatic patients to exposure to soybean dust, having led to their being affected during the epidemics of asthma in Barcelona. PMID- 9372650 TI - Evidence for linkage between asthma/atopy in childhood and chromosome 5q31-q33 in a Japanese population. AB - Susceptibility to the development of asthma and other atopic diseases is known to be associated with genetic components, and several candidate genes have been reported to be linked to atopy in Caucasian populations. We conducted a study of linkage between asthma and markers on chromosomes 5q31-q33 and 11q13 in 68 Japanese families (306 members) by affected sib-pair analysis. Families for the linkage study were ascertained through asthmatic children visiting the allergy clinic. The results provide supportive evidence for linkage between asthma and gene markers in or near the interleukin-4 (IL-4) gene, the IL-9 gene, and D5S393 on chromosome 5q31-q33 (p = 0.0013, p = 0.018, and p = 0.0077, respectively). Linkage between atopic phenotype and these genetic markers was also suggested (p = 0.006, p = 0.01, and p < 0.0001 for atopy, respectively). However, we failed to find evidence for linkage of asthma or atopy to the IgE high-affinity receptor gene on 11q13 (p > 0.1). These findings indicate that beyond ethnicity, there are specific loci that contribute to susceptibility to atopy on chromosome 5q31-q33. In addition, our findings suggest that loci on chromosome 5q31-q33 are linked to the development of asthma in childhood. PMID- 9372652 TI - Inspiratory maneuver effects on peak expiratory flow. Role of lung elastic recoil and expiratory pressure. AB - We investigated the effects of two different inspiratory maneuvers (fast or slow) on the ability of normal subjects to generate peak expiratory flows (PEF) and maximal dynamic expiratory pressures (Pexp) during the performance of a forced vital capacity maneuver. During the fast maneuver (F), the subject inspired rapidly to total lung capacity (TLC) and immediately performed a maximal expiration, whereas in the slow maneuver (S) the subject inspired slowly to TLC, paused for 4-5 s at TLC and then performed a maximal expiration. Ten normal subjects performed a series of such maneuvers. In addition to PEF and Pexp, we measured EMG activity of abdominal (EMGabd) and rib cage muscles, and lung elastic recoil pressure (PesL). Overall, F yielded higher PEF values than S (by approximately 7%); in addition, PesL, Pexp, rate of rise of Pexp (dPexp/dt), and EMGabd were similarly higher with F than with S (p < 0.05 for all). Analysis of individual data showed that the intermaneuver differences in PEF were largely explained by differences in PesL, Pexp or dPexp/dt. Our data suggest that, in comparison with the slow maneuver, the fast maneuver induces a greater change in both the lung elastic recoil and expiratory muscle activation which account for differences in PEF between the two maneuvers. The enhanced expiratory muscle activation with the fast maneuver suggests a specific inspiratory-expiratory muscle interaction analogous to agonist-antagonist interactions described for skeletal muscles. PMID- 9372653 TI - In vivo salicylate hydroxylation: a potential biomarker for assessing acute ozone exposure and effects in humans. AB - Ozone is known to yield hydroxyl radical, which may contribute to ozone-mediated lung injury. In the presence of hydroxyl radical, salicylate is hydroxylated to form 2,3-dihydroxybenzoic acid (2,3-DHBA). There is no evidence of enzymatic formation of 2,3-DHBA. We hypothesized that salicylate hydroxylation might be used as a biomarker indicating human exposure to ozone. Healthy, nonsmoking volunteers, 18 to 34 yr of age, were given acetylsalicylic acid (975 mg) or placebo orally 0.5 h before an exposure. Subjects were exposed to ozone (0.12 or 0.4 ppm) or filtered air in an environmental chamber for 2 h, while performing intermittent exercise. Results indicate significant decrements in FVC, FEV1.0, forced expiratory flows at 50% and 75% of FVC, and peak expiratory flow rate, and an increase in airway resistance, after exposure to 0.4 ppm ozone in comparison with air control (p < 0.05). Exposure to 0.4 ppm ozone also resulted in increased symptom numbers and severity (p < 0.05). When subjects were exposed to 0.12 ppm ozone, changes of pulmonary function and symptoms reported were minimal. Plasma concentration of 2,3-DHBA was significantly increased after exposure to 0.12 and 0.4 ppm ozone in comparison with air control (p < 0.05). There was a significant correlation between ozone-induced changes of pulmonary function and normalized salicylate hydroxylation (p < 0.05). The results indicate that exposure to ozone can initiate in vivo production of hydroxyl radical, a potent reactive agent. Salicylate hydroxylation may then serve as a sensitive dosimetric biomarker for ozone exposure, even at subclinical ozone exposure levels. PMID- 9372654 TI - Is bronchial hyperresponsiveness more frequent in women than in men? A population based study. AB - To test the hypothesis that a greater proportion of women than men react to methacholine challenge and investigate the possible reasons for any differences observed, we recruited 495 subjects 20 to 44 yr of age (50.9% male) in Paris and 304 subjects (51.3% male) in Montpellier (France), as part of the European Community Respiratory Health Survey. The proportion of responders (PD20 < or = 4 mg methacholine) was 33.7% in women and 11.9% in men (odds ratio = 3.8; 95% confidence interval = 2.4-6.0) in Paris and 43.2% in women and 29.5% in men (odds ratio = 1.8; 95% confidence interval = 1.1-2.9) in Montpellier. These differences could not be explained by asthma, respiratory symptoms, atopy, or lung function parameters. In stepwise logistic regressions including sex, asthma, and asthma like symptoms, nasal allergies, atopy, baseline FEV1, FEV1%pred, FVC, and FEV1%FVC, the odds-ratios for the effect of female sex on PD20 < or = 4 mg methacholine were 5.2 (3.0-9.0) in Paris and 2.2 (1.2-3.8) in Montpellier. Reacting to low doses of methacholine (PD20 < or = 0.5 mg) was associated with asthma and atopy in both men and women. In contrast, reacting to doses between 0.5 and 4 mg was associated with asthma and atopy only in men and with heavy tobacco consumption only in women. We conclude that the excess of hyperresponsiveness in women is not due to their having smaller lung size or airway caliber than men and may be related to a greater susceptibility to smoking. PMID- 9372655 TI - The effect of segmental bronchoprovocation with allergen on airway lymphocyte function. AB - We hypothesized that allergen-induced airway eosinophilia is linked to activation or recruitment of T cells in the airway and generation of interleukin-5 (IL-5). To evaluate this hypothesis, we performed bronchoscopy with segmental antigen bronchoprovocation in 12 atopic subjects. Bronchoalveolar lavage (BAL) was done 5 min and 48 h after challenge with saline or antigen. Airway cells were isolated and then stimulated ex vivo with a T-cell mitogen, phytohemagglutinin (PHA), and cytokine release was determined. Cells retrieved from the saline-challenged segment secreted principally interferon-gamma (IFN-gamma) and IL-2. In contrast, cells obtained 48 h after allergen challenge secreted high levels of IL-5 and small but increased amounts of IL-4, IL-10, and granulocyte-macrophage colony stimulating factor (GM-CSF). Although CD4+ T cells were a major source of IL-5, there were no significant changes in the relative proportion of CD4+ cells in response to bronchoprovocation. Additionally, ex vivo secretion of IL-5 by airway cells correlated closely with amounts of IL-5 and eosinophils present in the bronchoalveolar lavage fluid (BALF). These observations suggest that following exposure to allergen, airway T cells are functionally but not phenotypically different from resident airway T cells, and that T cells within the airway contribute to eosinophilic airway inflammation through the secretion of IL-5. PMID- 9372656 TI - Endothelin-1 secretion by alveolar macrophages in systemic sclerosis. AB - Endothelin-1 (ET-1), a potent fibroblast/smooth muscle cells mitogen, has been implicated in the pathogenesis of systemic sclerosis lung disease (SSc). Since monocytes and macrophages are thought to be activated in SSc, we hypothesized that alveolar macrophages (AM) and their precursors blood monocytes from patients with SSc produced more ET-1 than cells from healthy subjects. ET-1 and big ET-1 concentrations were measured in plasma, in bronchoalveolar lavage (BAL) fluids and in cell culture supernatants from monocytes and alveolar macrophages derived from 13 patients with definite SSc with lung involvement and from 10 control subjects. Plasma and BAL fluid ET-1 and big ET-1 levels were similar in both controls and patients with SSc. ET-1 and big ET-1 concentrations in unstimulated alveolar macrophage supernatants were similar in both groups. In contrast, LPS stimulated alveolar macrophages from patients with SSc secreted higher amounts of ET-1 and big ET-1 than control subjects. ET-1 and big ET-1 concentrations in monocyte supernatants (either LPS-stimulated or not) were not different in patients and controls. These results show that AM from patients with SSc are hyperresponsive to LPS in vitro in terms of ET-1 and big ET-1 production and suggest that AM could participate in vivo in the overproduction of this potentially profibrotic mediator in patients with SSc. PMID- 9372657 TI - Tumor necrosis factor-alpha gene polymorphism in chronic bronchitis. AB - Airway inflammation is an important pathologic feature in chronic bronchitis, and we hypothesized that individuals with greater inflammatory responses may be more likely to acquire the disease. A polymorphism at -308 position of the tumor necrosis factor-alpha (TNF-alpha) gene has been described, with the rarer allele, TNF2, demonstrated to have higher inducibility in vitro. We investigated the distribution of this polymorphism in a case-control study. The genotype was determined in 42 male patients with chronic bronchitis, 42 sex-, age-, and smoking index-matched control subjects, and 99 random-sampled schoolchildren. We report here that the TNF2 allele is overrepresented in the patient group. The allele frequency of TNF2 is 5.1% in the schoolchildren, 2.4% in the control group, and 19% in the bronchitis group (p < 0.01). Carriage of the TNF2 allele confers a higher risk to the development of chronic bronchitis (odds ratio = 11.1, 95% CI = 2.89-42.57). The results demonstrate the important pathologic role of TNF-alpha in chronic bronchitis and suggest that greater inflammatory response may predispose an individual to this disease. PMID- 9372658 TI - Chronic bronchitis, shortness of breath, and airway obstruction by occupation in New Zealand. AB - The objectives of this study were to measure the population prevalence of symptoms of chronic obstructive lung disease and mild airway obstruction and to compare these between occupational groups. There were 1,609 subjects (63.9% response rate) who completed a respiratory questionnaire. Of these, 1,132 (70.4%) underwent pulmonary function testing (FEV1 and FVC). Twenty-one categories of current occupation were used for analysis. Four definitions of chronic obstructive pulmonary disease (COPD) were used: (1) chronic bronchitis, (2) chronic bronchitis with airway obstruction, (3) shortness of breath, and (4) shortness of breath with airway obstruction. For chronic bronchitis, adjusted prevalence odds ratios were significantly elevated for food processors other than bakers (OR = 2.83; 95% CI, 1.27 to 6.29) and chemical processors (OR = 18.84; 3.71 to 95.64). The combination of chronic bronchitis and mild airway obstruction (FEV1/FVC < 0.75) was associated with bakers (OR = 25.5; 3.86 to 168.53) and spray painters (OR = 14.40; 2.85-72.69). Shortness of breath was associated with hairdressers (OR = 2.75; 0.80 to 9.42) and bakers (OR = 6.72; 0.57 to 79.66), and nursing was associated with lower levels of shortness of breath (OR = 0.42; 0.16 to 1.15). Working ever with vapors, gases, dust, or fumes was significantly associated with chronic bronchitis and airway obstruction (OR = 3.13; 1.07 to 9.12). This population-based study has identified certain occupations with increased prevalence of chronic bronchitis and COPD. PMID- 9372659 TI - The effect of alpha-tocopherol and beta-carotene supplementation on COPD symptoms. AB - The effects of alpha-tocopherol (50 mg/d) and beta-carotene (20 mg/d) supplementation on symptoms of chronic obstructive pulmonary disease were studied among the 29,133 participants of the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study undertaken to investigate the effects of these two substances in the prevention of lung and other cancers. During the follow-up the supplementations did not affect the recurrence or incidence of chronic cough, phlegm, or dyspnea. The prevalence of chronic bronchitis and dyspnea at baseline was lower among those with high dietary intake of beta-carotene (OR = 0.78 and 0.67, respectively) or vitamin E (OR = 0.87 and 0.77) and high serum beta carotene (OR = 0.59 and 0.62) and alpha-tocopherol (OR = 0.76 and 0.82). High intake and serum levels of retinol were associated with low prevalence of dyspnea (OR = 0.84 and 0.80, respectively) but not with chronic bronchitis. The results indicate no benefit from supplementation with alpha-tocopherol or beta-carotene on the symptoms of chronic obstructive pulmonary disorders but support the beneficial effect of dietary intake of fruits and vegetables rich in these compounds. PMID- 9372660 TI - Elevated serum levels of mucin-associated antigen in patients with acute respiratory distress syndrome. AB - Increased serum levels of mucin-associated antigen have been previously demonstrated in patients with cystic fibrosis (CF) and interstitial pneumonia, and in lung-transplant recipients. The present study assessed the serum airway mucin levels in patients with acute respiratory distress syndrome (ARDS). An enzyme-linked immunosorbent assay (ELISA) method with a human-airway-mucin specific monoclonal antibody (17Q2) was used to measure serum mucin levels in normal subjects, chronic smokers, patients with chronic bronchitis and other pulmonary diseases, patients with acute cardiogenic lung edema, and patients with ARDS. The serum mucin levels measured 9.9 +/- 0.8 ng/ml (mean +/- SEM, n = 59) in normal subjects, 12.7 +/- 1.6 ng/ml (n = 29) in chronic smokers, 21.8 +/- 1.9 ng/ml (n = 28) in patients with chronic bronchitis and other pulmonary diseases, 9.0 +/- 3.1 ng/ml (n = 5) in patients with acute cardiogenic lung edema. The serum mucin level was 53.8 +/- 6.6 ng/ml (n = 13) in patients with ARDS (p < 0.05, as compared with the four other groups). Serial measurements of serum mucin levels were obtained in patients with ARDS. Statistical analysis showed an inverse correlation of serial measurements of serum mucin with static respiratory system compliance (p = 0.021), an inverse correlation of sequential serum mucin levels and log(Pa(O2)/Fl(O2)) (p = 0.016), and a positive correlation of sequential serum mucin levels and lung injury score (LIS) (p = 0.019). Gel filtration analysis showed that mucin-associated antigens in ARDS sera were polydispersed and smaller than the antigens in normal sera. This study indicates that an increasing amount of degraded mucin occurs in patients with ARDS. PMID- 9372661 TI - Temporal hemodynamic effects of permissive hypercapnia associated with ideal PEEP in ARDS. AB - The associated use of permissive hypercapnia (PHY) and high PEEP levels (PEEP(IDEAL)) has been recently indicated as part of a lung-protective-approach (LPA) in acute respiratory distress syndrome (ARDS). However, the net hemodynamic effect produced by this association is not known. We analyzed the temporal hemodynamic effects of this combined strategy in 48 patients (mean age 34 +/- 13 yr) with ARDS, focusing on its immediate (after 1 h), early (first 36 h), and late (2nd-7th d) consequences. Twenty-five patients were submitted to LPA--with the combined use of permissive hypercapnia (PHY), VT < 6 ml/kg, distending pressures above PEEP < 20 cm H2O, and PEEP 2 cm H2O above the lower inflection point on the static inspiratory P-V curve (P(FLEX))- and 23 control patients were submitted to conventional mechanical ventilation. LPA was initiated at once, resulting in an immediate increase in heart rate (p = 0.0002), cardiac output (p = 0.0002), oxygen delivery (DO2l, p = 0.0003), and mixed venous Po2 (p = 0.0006), with a maintained systemic oxygen consumption (p = 0.52). The mean pulmonary arterial pressure markedly increased (mean increment 8.8 mm Hg; p < 0.0001), but the pulmonary vascular resistance did not change (p = 0.32). Cardiac filling pressures increased (p < 0.001) and the systemic vascular resistance fell (p = 0.003). All these alterations were progressively attenuated in the course of the first 36 h, despite persisting hypercapnia. Plasma lactate suffered a progressive decrement along the early period in LPA but not in control patients (p < 0.0001). No hemodynamic consequences of LPA were noticed in the late period and renal function was preserved. A multivariate analysis suggested that these acute hyperdynamic effects were related to respiratory acidosis, with no depressant effects ascribed to high PEEP levels. In contrast, high plateau pressures were associated with cardiovascular depression. Thus, as long as sufficiently low distending pressures are concomitantly applied, the sudden installation of PHY plus PEEP(IDEAL) induces a transitory hyperdynamic state and pulmonary hypertension without harmful consequences to this young ARDS population. PMID- 9372662 TI - Prognostic factors of severe Legionella pneumonia requiring admission to ICU. AB - Despite the fact that the epidemiology of community-acquired pneumonia and nosocomial Legionella infection is well known, there are no specific reports dealing with severe cases of Legionella pneumophila pneumonia admitted to intensive care units. We undertook a prospective study upon 84 patients with a reliable diagnosis of L. pneumophila pneumonia that required ICU admission. The study assessed the prognostic factors, clinical, radiological and outcome variables of both nosocomial (n = 33) and community-acquired (n = 51) cases of L. pneumophila pneumonia. The following variables were more common in nosocomial acquired as compared to community-acquired Legionella pneumonia: Chronic obstructive pulmonary disease (COPD) (64 versus 41%), cardiac disease (39 versus 10%), chronic renal failure (21 versus 4%), alcoholism (54 versus 18%), septic shock (33 versus 16%), and unilateral chest X-ray involvement (61 versus 39%). The crude mortality rate in this study was 30% (25 of 84) with no differences when comparing mortality between nosocomial (9, 27%) to community-acquired (16, 31%) types. The univariate analysis showed that cardiac disease, diabetes mellitus, creatinine > or = 1.8 mg/dl, septic shock, chest X-ray extension, mechanical ventilation, hyponatremia < or = 136 mEq/L, PACO2/FIO2 < 130, and blood urea levels > or = 30 mg/dl were factors related to poor outcome. On the other hand, the following two variables were related to better outcome: adequate treatment for Legionella and pneumonia improvement. The logistic regression analysis demonstrated that APACHE II score > 15 at admission (RR: 11.5; 95% CI 1.75 to 76.1; p = 0.025), and serum Na levels < or = 136 (RR: 21.3; 95% CI 1.11 to 408; p = 0.023), were the only independent factors related to death. On the other hand, improving pneumonia is associated with better outcome in Legionnaires' disease than for patients not having improving pneumonia (RR: 0.019; 95% CI: 0.036 to 0.106; p < 0.0001). A better understanding of the prognostic factors in cases of severe Legionella pneumonia will optimize our therapeutic approach in this disease and help to decrease both its mortality and morbidity rates. PMID- 9372663 TI - Structure-function relationships in the septic rat heart. AB - Myocardial edema and histologic changes consistent with tissue injury are reported in association with sepsis-induced myocardial depression. The objective of the present study was to determine whether, in the absence of shock, such changes (assessed by studying microvascular albumin flux, tissue edema, and morphometry) are prerequisites for the development of contractile dysfunction in sepsis. Sprague-Dawley rats were randomized into groups for either cecal ligation and perforation (CLP) or sham study. Twenty-four hours after entry of animals into the study, their myocardial function was assessed with the Langendorff isolated heart technique. Left-ventricular developed pressure (preload: 5 mm Hg) was reduced in CLP animals (34.9 +/- 3.3 mm Hg, n = 10) as compared with time matched controls (46.4 +/- 4.0 mm Hg, n = 8, p < 0.05, unpaired t test). This was associated with a significant reduction in the maximal rate of increase (+ dP/dt(max)) and decrease (-dP/dt(max)) in left ventricular pressure in the CLP group (sham versus CLP, unpaired t test, p < 0.05). Upon reperfusion, after 30 min of ischemia, left ventricular resting tension was decreased in CLP as compared with sham-treated animals (sham versus CLP, analysis of variance (ANOVA) with repeated measures, p < 0.05). At 24 h, sepsis was not associated with myocardial edema (wet:dry weight ratio, sham = 4.094 +/- 0.098, n = 10; CLP = 4.185 +/- 0.066, n = 7), and tissue albumin flux was reduced (sham = 194 +/- 27 microliters. h-1. g dry wt-1, n = 10; CLP = 100 +/- 14 microliters. h-1. g dry wt 1, n = 7). In tissue processed for electron microscopy, we found no evidence of tissue injury or edema at either 24 or 48 h after CLP. We conclude that polymicrobial normotensive sepsis causes myocardial contractile depression in the absence of changes in myocardial structure. PMID- 9372664 TI - Effect of tPA on regional lung perfusion in unilobar canine pulmonary thromboembolism. AB - We investigated effects of tissue-type plasminogen activator (tPA) on regional pulmonary arterial hemodynamics in pulmonary thromboembolism (PTE) in a canine model of unilobar PTE. Ten beagle dogs were divided into two groups-tPA (n = 5) and control group (n = 5). In each dog an artificial blood circuit (ABC) consisting of a silicone tube and a cannulation-type electromagnetic blood flowmeter probe was placed at the left lower pulmonary artery. A unilobar PTE was induced by placing autologous clots into a metallic coil inside the ABC. The CO2 sampling tubes were positioned at the orifice of the left lower bronchus and the trachea, and the end-expiratory CO2 partial pressure (PET(CO2)) was measured. In the tPA group, blood flow at the left lower pulmonary artery (LL-flow) was improved to near baseline within approximately 30 min of receiving tPA, and PET(CO2) at the left lower bronchus (LL-PET(CO2)) increased in direct correlation with LL-flow. The hemodynamic improvement after tPA therapy correlated with the partial pressure of the regional pulmonary expiratory CO2. Moreover, it was suggested that changes in physiologic conditions in PTE were not determined by clot quantity alone. PMID- 9372665 TI - Tuberculosis control policies in major metropolitan health departments in the United States. VI. Standard of practice in 1996. AB - Since 1980, we have surveyed at 4-yr intervals the metropolitan health departments initially reporting > 250 cases of tuberculosis to determine the perceived standard of practice for tuberculosis control and the factors affecting formulation of treatment policies. Between 1992 and 1996, use of supervised short course (6 to 9 mo) intermittent therapy with multiple drugs including isoniazid, ethambutol, pyrazinamide, and rifampin increased from 4.3% to 46% of all new patients. Pyrazinamide use for initial treatment for children has increased substantially and now predominates (74.2% of patients in 1996 versus 48.1% of patients in 1992). Duration of treatment, which was 20 +/- 2.1 mo in 1980, is now 8.00 +/- 2.29 mo in 1996. The incidence of human immunodeficiency virus associated tuberculosis, which was virtually unrecognized in 1984, has remained the same between 1992 and 1996 (18.0%). As in previous years, there was a wide variance among health departments in the incidence (< 5% to > 40%) of HIV associated tuberculosis. After years of funding decreases, there has been an impressive increase in resources in the past 4 yr. In 1988, mean budget allocation for health departments decreased by 7.9% versus the prior 4 yr and, in 1992, there was no overall change in budget allocation after inflation versus 1988. In 1996, however, funds for treatment increased by 84 +/- 33%. This increase in funding has been translated into the greatly expanded use of supervised intermittent therapy and aggressive screening programs, which likely have resulted in the decreased incidence of tuberculosis since the prior survey. PMID- 9372666 TI - Geographic diversity in tuberculosis trends and directly observed therapy, New York City, 1991 to 1994. AB - The New York City tuberculosis (TB) case rate declined from 1991 to 1994 following more than a decade of increases. The present study investigated TB trends in New York City neighborhoods and their association with neighborhood specific rates of application of directly observed therapy (DOT). Using Poisson regression models, TB trends in each of New York City's 30 health districts were classified as increasing, decreasing, or stable, as indicated respectively by significant positive, negative, or nonsignificant regression coefficient. Case counts increased in four health districts, decreased in 10, and were stable in 16. Decreasing TB was associated with a higher rate of application of DOT. TB cases among foreign-born persons increased in 12 health districts and were stable in 18, whereas cases among persons born in the United States decreased in 19 and were stable in 11 districts. Among the foreign-born, increasing TB was not associated with a lesser rate of application of DOT. These data provide some support for the role of DOT in containing TB, but also suggest that the application of DOT among foreign-born residents is less effective than among United States-born residents. This may be due to a greater proportion of TB cases among the foreign-born being due to reactivation of TB rather than new infection. PMID- 9372667 TI - Role of bronchoalveolar lavage in predicting survival of patients with human immunodeficiency virus infection. AB - In this multicenter study, we investigated the prognostic factors that influence the risk of death in patients with human immunodeficiency virus (HIV) infection. Clinical and laboratory indices obtained from 161 HIV-seropositive patients who underwent a detailed morphologic and immunophenotypic evaluation of bronchoalveolar lavage (BAL) and peripheral blood cell populations were retrospectively analyzed. In 155 patients, death occurred within the 48-mo follow up (mean follow-up: 14.8 mo; range: 1 to 48 mo). In the univariate analysis, the patient's age (> 30 yr), HIV disease status, HIV transmission category, number of opportunistic pathogens isolated from the BAL, percentage of BAL neutrophils, and low number of BAL CD4 T cells were predictive of increased mortality. In contrast, the presence of an alveolitis or an increase in the numbers of alveolar macrophages and CD3 T cells was associated with a decreased mortality. In the multivariate analysis, significant independent predictors were age, risk factor for HIV, and presence of an alveolitis. Furthermore, patients with a low number of BAL CD4 T cells had a particularly poor prognosis while the CD4 T-cell count in the peripheral blood (< 50 cells/mm3 in the majority of our patients) had a negligible effect on predicting survival. Our findings suggest the clinical utility of BAL analysis in patients infected with HIV. PMID- 9372668 TI - Empyema thoracis and lung abscess caused by viridans streptococci. AB - We retrospectively studied the bacteriology and clinical features of empyema thoracis and lung abscess caused by viridans streptococci in 72 patients seen from January 1984 to September 1996. A total of 76 strains of viridans streptococci were isolated, of which the most common isolates were Streptococcus constellatus (21 strains), S. intermedius (17), and S. sanguis (10). Species belonging to the S. milleri group accounted for the majority (68%) of isolates. In 38 (53%) patients these organisms were recognized as the sole pathogens. Of the 72 patients, 53 had empyema, 14 had lung abscesses, and five had both empyema and lung abscess. Forty-six (64%) patients had underlying diseases. Of these, malignancies were the most common (17 patients), followed by diabetes mellitus (12 patients) and central nervous system diseases (10 patients). Of the 48 patients who underwent chest-tube drainage, 27 (56%) received further treatments, including intrapleural streptokinase (18 cases), surgery (9), and both intrapleural streptokinase and surgery (3). Two (14%) of the patients with lung abscess alone underwent surgical treatment. Although all viridans streptococcal isolates were susceptible to penicillin, the patients in the study had a high mortality (21%). Univariate and multivariate analysis of data for patients with empyema alone (n = 53) showed a significantly increased risk of death in those with underlying malignancy (OR = 16.0, p = 0.023) and those with non-S. milleri group isolates (OR = 3.72, p = 0.030). These data imply a strong clinical significance of viridans streptococci in the pathogenesis of empyema and lung abscess, as well as the need for species identification of viridans streptococci in patients with pleuropulmonary diseases. PMID- 9372669 TI - Cytokines and soluble cytokine receptors in pleural effusions from septic and nonseptic patients. AB - The balance between proinflammatory cytokines and their inhibitors has rarely been investigated in pleural effusions of nonmalignant or noninfectious origin. To evaluate the impact of a lung and/or intrathoracic infection in such a circumstance, we compared the levels of proinflammatory cytokines (interleukin-8 [IL-8]); tumor necrosis factor-alpha (TNF-alpha); the cytokine antagonists and inhibitors (IL-1 receptor antagonist [IL-1ra]) and soluble TNF receptors Types I and II (sTNFRI, sTNFRII); and antiinflammatory cytokines (transforming growth factor-beta [TGF-beta]) in pleural effusion and plasma from septic (n = 15) and nonseptic (n = 9) patients. In addition, we analyzed the levels of IL-6 and its soluble receptor (sIL-6R). Bronchoalveolar lavage fluids (BALFs) were also studied in a few septic patients. High and nonsignificantly different levels of cytokines and inhibitors were detected in both groups of patients. The levels of IL-6 and sTNFRI and sTNFRII in pleural effusion were higher than in plasma, whereas the levels of IL-1ra and sIL-6R were higher in plasma. The levels of sIL 6R influenced the bioactivity of IL-6. There was no correlation between the levels of cytokines in plasma and in pleural effusion. In contrast, a significant correlation was observed for the soluble receptors sIL-6R (r = 0.67, p < 0.001), sTNFRI (r = 0.76, p < 0.001) and sTNFRII (r = 0.66, p = 0.001). Furthermore, a high correlation was found between the levels of both forms of sTNFRs in plasma (r = 0.95, p < 0.001) and in pleural effusion (r = 0.79, p < 0.001). In addition, a correlation was observed between the levels of TGF-beta in pleural effusion and in BALF. The highest levels of some markers in plasma and of others in pleura argue in favor of both a systemic and a compartmentalized response, independently of the presence of infection. Because cytokines can be trapped by the surrounding cells in their environment, measurable levels of cytokines in biologic fluids represent the "tip of the iceberg," which is not the case for soluble receptors. The correlations of these latter markers between plasma and pleura strongly suggest that exchanges between both compartments can occur in both directions. PMID- 9372670 TI - Cromolyn sodium prophylaxis inhibits pulmonary proinflammatory cytokines in infants at high risk for bronchopulmonary dysplasia. AB - An imbalance of proinflammatory cytokines such as TNF-alpha, IL-1 beta, and the neutrophil chemotactic factor IL-8 and inhibitors (e.g., soluble TNF receptors and IL-1ra) in the lung during the first week of life may contribute to prolonged pulmonary inflammation and fibrosis in bronchopulmonary dysplasia (BPD). Disodium cromoglycate (DSCG) has anti-inflammatory effects in asthma, a disease with many similarities with BPD. In a prospective, randomized, blinded study, we examined whether early DSCG therapy inhibits proinflammatory cytokines in infants at risk for BPD. Twenty-six infants who were identified as high risk (> or = 75% probability) for oxygen-dependency at 28 d by a 12-h predictive score and survived 48 h were randomized to nebulized DSCG 20 mg (n = 13) or 2 cc NS (control, n = 13) every 6 h from Day 3 to Day 28. Lung lavage was collected on Day 3 (pre-study) and Day 7 and analyzed for cell count and differential and TNF alpha, sTNFR1, sTNFR2, IL-1 beta, IL-1ra, and IL-8 concentrations. The groups' pre-study lavage cytokine concentrations were similar, but TNF-alpha and IL-8 concentrations were 3.6- and 4.9-fold lower in the DSCG group on Day 7 compared with levels in the control group. Soluble TNF receptors were unaffected by DSCG. There was a trend towards lower IL-1 beta levels in DSCG-treated infants on Day 7, but IL-1ra levels were unaffected by DSCG therapy. Three control subjects, but no DSCG-treated infants, died during the study period (p = 0.07). There were no significant differences between survivors of the two groups for oxygen-dependency at 28 d (100% control subjects; 85% DSCG). These results suggest that nebulized DSCG may exert an anti-inflammatory effect in the lungs of infants < or = 1,000 g at risk for BPD. PMID- 9372671 TI - Magnitude estimation of inspiratory resistive loads in children with life threatening asthma. AB - The perception of inspiratory resistive (R) loads was studied in nonasthmatic children and in children with a history of life-threatening asthma. It was hypothesized that the children with life-threatening asthma would have a reduced sensitivity to added mechanical loads as measured by magnitude estimation of resistive loads (ME). The subjects were screened from the experimenter and seated in a sound-isolated room in a lounge chair facing an oscilloscope, and they respired through a nonbreathing valve with the inspiratory port connected to the loading manifold. The oscilloscope displayed the inspiratory V, and each subject was required to inspire to the same peak V for each breath. The subject's inspiratory background R was measured by the interrupter method. Five magnitudes of R loads and no-load were presented randomly 10 times each for a single inspiration after the illumination of a light cue. The subjects were initially given a training trial breathing to the V target. The loads were presented in two trials. The load was estimated using the modified Borg scale. The slope of the log-log relationship between R load magnitude and the ME is a measure of the sensitivity of the subject to R loads. The slope for children with life threatening asthma was significantly less than that for asthmatic and nonasthmatic children. There were no significant differences in the slope related to race, sex or age in the nonasthmatic children or in the asthmatic children. The reduced sensitivity to increased R loads suggests that these children are at risk of a life-threatening asthmatic attack in part because of an underestimation or delay in the perception of the increased mechanical load that occurs during an asthmatic attack. PMID- 9372673 TI - Evaluation of supported upper limb exercise capacity in patients with cystic fibrosis. AB - Physiological responses to upper limb exercise have not been well documented in patients with cystic fibrosis (CF). This is the first study to quantify ventilatory responses to supported incremental upper limb exercise in this patient group. Twenty-four subjects with CF, with a wide range of pulmonary impairment, and ten normal control subjects were studied. Subjects performed pulmonary function tests and incremental arm and leg exercise to peak work capacity on an arm crank and bicycle ergometer. All subjects performed less work with the arms than legs. At an equivalent oxygen consumption, ventilation was higher for arm work than leg work. This higher ventilation was achieved mainly through a higher frequency of breathing. Only CF subjects with severe pulmonary impairment (FEV1 < 40% predicted, FEF25-75% < 20% predicted) had a reduced arm work capacity compared with control subjects. At peak arm work, these subjects had a mean ventilation to maximum voluntary ventilation ratio (VE/MVV) of 106% +/ 25, while maximum heart rate was less than 80% predicted. Despite the high ventilatory requirement for arm exercise, arm work capacity was well maintained in subjects with CF until severe lung disease impaired the ability to further increase ventilation. PMID- 9372672 TI - Regional variability of lung inflammation in cystic fibrosis. AB - Chest radiography in patients with cystic fibrosis (CF) frequently shows more severe changes in the upper lobes. We performed bronchoalveolar lavage (BAL) on 12 clinically stable, young adult patients with CF to determine whether inflammation varies significantly among geographically distinct areas of the lung. We found that absolute numbers of neutrophils were generally greater in BAL fluid from the upper lobe (25.7 +/- 7.9 x 10(5) neutrophils/ml [mean +/- SEM]) of the right lung than that obtained from the right lower lobe (6.8 +/- 2.8 x 10(5) neutrophils/ml; p < 0.01). The mean value of unopposed neutrophil elastase activity in upper-lobe BAL fluid (227 +/- 91 nmol peptide hydrolyzed/ml/min) was also significantly greater than that in lower-lobe BAL fluid (84 +/- 43 nmol/peptide hydrolyzed/ml/ min; p < 0.01), and similar differences were found for myeloperoxidase activity and DNA content. Neutrophil influx and unopposed neutrophil elastase for a given region correlated inversely with lung function or percentage of ideal body weight, and upper-versus lower-lobe differences were more pronounced in subjects with better preservation of lung function. Our findings suggest that regional variation in inflammation must be considered when utilizing BAL to study lower respiratory tract inflammation in CF or to monitor responses to therapeutic interventions that can potentially diminish lung inflammation. Our findings may also have implications for the study of the natural history of lung inflammation and infection in neonates, infants, and young children with CF. PMID- 9372674 TI - Left ventricular volume in patients with heart failure and Cheyne-Stokes respiration during sleep. AB - In patients with congestive heart failure (CHF), elevated, left ventricular (LV) volume might lead to pulmonary congestion and hypocapnia, which would create a predisposition to the development of Cheyne-Stokes respiration with central sleep apnea (CSR-CSA). In addition, because LV volume affects cardiac output, it should influence the lengths of hyperpneas. We therefore evaluated LV volumes and transcutaneous PCO2 (PtcCO2) during wakefulness and stage 2 sleep in 16 patients with CHF due to nonischemic dilated cardiomyopathy (NIDC). Data were then compared between those with (n = 7) and those without CSR-CSA (n = 9). LV end diastolic volume (LVEDV) was significantly higher in patients with than those without CSR-CSA (585 +/- 118 versus 312 +/- 41 ml, p < 0.05). Compared with patients without CSR-CSA, those with CSR-CSA had lower mean stage 2 sleep PtcCO2 (36.3 +/- 2.2 versus 41.2 +/- 1.2 mm Hg, p < 0.05) and a lesser change in PtcCO2 from wakefulness to stage 2 sleep (-0.4 +/- 0.3 versus 2.0 +/- 0.4 mm Hg, p < 0.001). Among patients with CSR-CSA, hyperpnea length was inversely related to LVEDV (R = 0.769, p = 0.043) owing to the direct relationship of cardiac output to LVEDV (R = 0.791, p = 0.034). We conclude that CSR-CSA in patients with CHF due to NIDC is associated with increased LV volumes possibly through the direct or indirect influence of LV volume on PaCO2 and cardiac output. PMID- 9372675 TI - Comparison of train-of-four and best clinical assessment during continuous paralysis. AB - Train-of-four (TOF) monitoring is recommended in published guidelines during use of continuous-infusion neuromuscular blocking agents (NMB) in the intensive care unit (ICU). To test that recommendation, dual protocols were established in a medical ICU after intensive nursing education. Paralyzed patients received either TOF monitoring with a goal of three twitches or best clinical assessment while receiving atracurium by continuous infusion. Demographics and mean duration of paralysis of 20 patients in the TOF group were no different than that of the 16 patients in the best clinical assessment group. Although most patients demonstrated atracurium tolerance over time, there was no difference between groups in total mg (+/- SEM) infused (10,460 +/- 2,409 versus 9,201 +/- 3,237) or mean microgram/kg/min (15.2 +/- 1.5 versus 12.0 +/- 1.1). The time to clinical recovery was no different between groups (50 +/- 10 versus 45 +/- 12 min). Two complications occurred in the TOF group, with pulmonary emboli despite prophylaxis and an unrecognized cerebrovascular accident in one patient each. We conclude that careful titration of NMB using clinical bedside markers should remain the standard of care with these drugs. PMID- 9372676 TI - Recovery of PdiTwitch following the induction of diaphragm fatigue in normal subjects. AB - Low frequency diaphragm fatigue (LFF) may play a major role in the pathogenesis of ventilatory failure; however, recovery from LFF is not well studied. We measured transdiaphragmatic twitch pressure (PdiT) at FRC (using a reduction of PdiT as an index of LFF) and maximum transdiaphragmatic pressure (Pdimax) before and after the induction of diaphragm fatigue in seven normal subjects, age 31 +/- 3 yr (mean +/- SD). Fatigue was induced by breathing through an inspiratory resistive load. PdiT produced by bilateral transcutaneous supramaximal electrophrenic stimulation was measured at baseline, 15, 30 min, 1, 2, 3, 4 h, and then 1 to 3 times between hour 20-25 post-fatigue. Pdimax estimated by twitch occlusion was measured at baseline, 30 min, 2-3, and 20-25 h post-fatigue. Pre fatigue values (mean +/- SE) were: PdiT 23.6 +/- 2.5 cm H2O. The mean +/- SD time to fatigue was 25.3 +/- 12.3 min. Post-fatigue PdiT was reduced to 50%, and by 3 h was 72% of the initial value; 100% by 25 h. Pdimax was reduced to 75% post fatigue, but recovered to 87% by 3 h, and 100% by 25 h. We concluded that recovery of PdiT and Pdimax in normal subjects starts to occur within the first few hours following diaphragm fatigue, and is complete by 25 h. PMID- 9372677 TI - Effect of N-acetylcysteine on human diaphragm strength and fatigability. AB - Free radical injury is believed to be important in diaphragm dysfunction. N Acetylcysteine (NAC) is a potent free radical scavenger shown in animal models to attenuate diaphragm fatigue; however, its effects on human diaphragm function are unknown. We assessed diaphragm function by electrophrenic twitch stimulation (PdiT) and twitch occlusion (to yield Pdimax) in four healthy subjects 35 +/- 3 yr of age (mean +/- SD). We intravenously administered NAC (150 mg/kg in 250 ml D5W) or placebo (CON) (250 ml D5W) in a randomized manner after subjects were premedicated with antihistamines. There were no significant side effects with the infusion. After infusion, we measured baseline Pdimax and PdiT at FRC. Diaphragm fatigue was then induced by subjects breathing through an inspiratory resistive load. Pdimax and PdiT were then measured at 15 to 30 min and 1, 2, 3, 4, and 20 25 h after fatigue. Times to fatigue were 13 +/- 4 min (CON) and 21 +/- 6 min (NAC) (p = 0.04). At 15 min after fatigue, PdiT was reduced to 40% (CON) compared with 30% (NAC) initial PdiT value (p = 0.05). Other twitch characteristics (maximal rate of relaxation and maximal contraction rate) were reduced to a greater degree after placebo compared with NAC. There were no significant differences in the rate of recovery between CON and NAC. Pdimax at 30 min after fatigue was significantly greater with NAC; however, at 1 h after fatigue, Pdimax for CON and NAC were not different, suggesting similar rates of recovery in high frequency fatigue. These data suggest that NAC may attenuate low-frequency human diaphragm fatigue. PMID- 9372678 TI - Hyporeactivity of rat diaphragmatic arterioles after exposure to hypoxia in vivo. Role of the endothelium. AB - The effect of prior in vivo hypoxia on the in vitro responses to changes in transmural pressure, alpha-adrenoceptor activation, and depolarization with KCl were evaluated in first-order diaphragmatic arterioles. Rats (n = 14 per group) were exposed to normoxia (controls) or to hypoxia (inspired O2 concentration = 10%) for 12 or 48 h. The arteriolar pressure-diameter relationships were recorded over a pressure range from 10 to 200 mm Hg. In separate groups of arterioles (n = 12 per group), the diaphragmatic arteriolar responses to phenylephrine (10(-8) to 10(-5 M) or KCl (10 to 100 mM) were determined after exposure to either room air or hypoxia for 48 h. In half of the arterioles studied, the endothelium was removed. After 12 h of hypoxia, the pressure-diameter relationship was normal in endothelialized arterioles but was shifted upward in de-endothelialized vessels (p < 0.05). After 48 h of hypoxia, the constrictor response to increasing transmural pressure was severely suppressed in all arterioles. The intraluminal diameters during activation with phenylephrine and KCl were larger in arterioles from rats exposed to hypoxia (103 +/- 8 and 81 +/- 7 microns, respectively) than in control arterioles (41 +/- 5 and 54 +/- 6 microns, respectively; p < 0.05 for differences). During maximum phenylephrine- and KCl-induced constriction in de endothelialized arterioles, diameters averaged 125 +/- 8 and 105 +/- 8 microns, respectively, for arterioles from hypoxic rats and 32 +/- 6 and 40 +/- 5 microns, respectively, for arterioles from control vessels. Exposure to hypoxia results in impairment of diaphragmatic arteriolar smooth muscle reactivity and reversal of the normal inhibitory influence of the endothelium on diaphragmatic arteriolar tone. PMID- 9372679 TI - Endurance training improves the resistance of rat diaphragm to exercise-induced oxidative stress. AB - The current study was designed to test the hypothesis that endurance training improves the ability of the diaphragm muscle to resist exercise-induced oxidative stress. Twenty-eight male Wistar rats were assigned to either untrained or trained groups. Trained rats were treadmill-trained for 9 wk. Each group was subdivided into acutely exercised or nonexercised groups. Diaphragm muscle from each rat was analyzed to determine the levels of certain antioxidant enzymes: Mn superoxide dismutase (Mn-SOD), Cu,Zn-superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase, and catalase. In addition, interleukin-1 and myeloperoxidase levels were determined. Endurance training upregulated all of the antioxidant enzymes. Conversely, acute exercise increased glutathione peroxidase and catalase in untrained rats, while it had no overt effect on any antioxidant enzymes in trained rats. Both Mn-SOD and Cu,Zn-SOD contents and activities were increased with endurance training. However, the mRNA expressions of both forms of SOD did not show any significant change with endurance training. Acute exercise also increased the levels of interleukin-1 and myeloperoxidase in untrained rats but not in trained rats. Moreover, acute exercise significantly increased the ability of neutrophils to produce superoxide, especially in untrained rats. The results from this study demonstrate that endurance training can upregulate certain antioxidant enzyme activities in rat diaphragm muscle, indicating the potential for improvement of the resistance to intracellular reactive oxygen species. The results of this study also suggest that acute exercise may cause oxidative damage in rat diaphragm through the activation of the inflammatory pathway and that endurance training may minimize such an extracellular oxidative stress by acute exercise. PMID- 9372680 TI - Sarcoidosis: TNF-alpha release from alveolar macrophages and serum level of sIL 2R are prognostic markers. AB - At the time of diagnosis, many sarcoidosis patients have no clinical indication for corticosteroid therapy, and prognostic parameters predicting deterioration are missing. In the present study, we investigated parameters derived from bronchoalveolar lavage (BAL) and serum in 77 patients with recently diagnosed sarcoidosis to test their predictive value. Patients were divided into a group with (Group A, n = 37) and a group without (Group B, n = 40) indications for therapy, and the course of the disease was evaluated after 5.7 +/- 0.4 mo. The CD4+/CD8+ lymphocyte ratio and percentage of BAL lymphocytes were of no predictive value. Release of tumor necrosis factor-alpha (TNF-alpha) from cultured alveolar macrophages (AM) was significantly increased in both groups (Group A = 1,872 +/- 428 pg/ml; Group B = 1,561 +/- 449 pg/ml) as compared with controls (220 +/- 37 pg/ml). In Group B, however, patients with a high level of TNF-alpha release had a significantly greater risk of disease progression than did those with normal TNF-alpha release (43.8% versus 8.3%, respectively). From the serologic parameters investigated, consisting of neopterin, angiotensin converting enzyme (ACE), and soluble interleukin-2 receptor (sIL-2R), only the last was of significant predictive value; 42.1% of sarcoidosis patients in Group B with a high level of sIL-2R experienced disease progression, whereas none of those with a normal level did. We conclude that TNF-alpha release and sIL-2R are suitable parameters for predicting disease progression in sarcoid patients who have no indication for therapy at the time of disease diagnosis. PMID- 9372681 TI - TCR V beta families in T cell clones from sarcoid lung parenchyma, BAL, and blood. AB - The TCR repertoire and the CD4/CD8 ratio of clones from peripheral blood (PB), transbronchial biopsies (TBB), and bronchoalveolar lavage (BAL) of 16 sarcoid patients was analyzed by staining the clones with monoclonal antibodies against nine V beta-families. We observed a striking increase in the CD4/CD8 ratio of the clones from BAL; whereas the CD4/CD8 ratio of the clones from PB was in the normal range. The CD4/CD8 ratio of the TBB-clones had also increased, but this increase did not reach the level of that of the BAL clones. The most prominent changes in the V beta percentages could be detected in the CD4+ subpopulation of the BAL-clones. The most abundant V beta families were V beta 5 in PB and BAL (11.8 and 28.6%, respectively) and V beta 6 in the TBB (12.4%). A similar compartmentalized V beta usage could be demonstrated in one patient with tuberculosis and one patient with HP. The increase in V beta 5, V beta 8, V beta 12, V beta 13.3, and V beta 19 in the BAL and the increase of V beta 5, V beta 6, V beta 13.3, and V beta 19 in the TBB suggest an antigen-driven activation of the T cells in both compartments. Differences in the V beta percentages between BAL and TBB and the lower CD4/CD8 ratio in the TBB, however, demonstrate a relative independence of the two compartments. PMID- 9372682 TI - HLA-DR predicts the prognosis in Scandinavian patients with pulmonary sarcoidosis. AB - Although most patients with sarcoidosis have a good prognosis, a significant proportion runs a more severe and prolonged disease course. There is no marker to distinguish these subpopulations of patients, however. To investigate the relationship between HLA haplotype and clinical course, 122 Scandinavian patients with sarcoidosis were genomically typed for HLA-DR, -DQA1 and -DQB1 alleles using PCR amplification with sequence-specific primers. Control subjects were 250 healthy Swedish volunteers. Patients were carefully clinically monitored for up to 10 yr. We found that HLA-DR17(3) was overrepresented among sarcoidosis patients (33%) compared with control subjects (17%, p < 0.001). Ninety-one patients were followed for more than 2 yr and classified into chronic or nonchronic patients, according to disease outcome. Among the 34 patients with a nonchronic form of sarcoidosis, 65% were DR17(3)-positive (p < 10(-5) versus control subjects). On the other hand, DR14(6) and DR15(2) were significantly associated with chronic disease. Even in patients with clinical manifestations that are normally associated with good prognosis, HLA typing enabled a subgrouping into two categories with significantly different clinical courses. Therefore, HLA class II typing is a valuable tool in predicting the outcome of the disease in Scandinavian sarcoidosis patients. PMID- 9372683 TI - Marijuana and cocaine impair alveolar macrophage function and cytokine production. AB - Use of marijuana and cocaine is on the rise in the United States. Although pulmonary toxicity from these drugs has occasionally been reported, little is known about their effects on the lung microenvironment. We evaluated the function of alveolar macrophages (AMs) recovered from the lungs of nonsmokers and habitual smokers of either tobacco, marijuana, or crack cocaine. AMs recovered from marijuana smokers were deficient in their ability to phagocytose Staphylococcus aureus (p < 0.01). AMs from marijuana smokers and from cocaine users were also severely limited in their ability to kill both bacteria and tumor cells (p < 0.01). Studies using NG-monomethyl-L-arginine monoacetate, an inhibitor of nitric oxide synthase, suggest that AMs from nonsmokers and tobacco smokers were able to use nitric oxide as an antibacterial effector molecule, while AMs from smokers of marijuana and cocaine were not. Finally, AMs from marijuana smokers, but not from smokers of tobacco or cocaine, produced less than normal amounts of tumor necrosis factor-alpha, granulocyte-macrophage colony-stimulating factor, and interleukin-6 when stimulated in culture with lipopolysaccharide. In contrast, the production of transforming growth factor-beta, an immunosuppressive cytokine, was similar in all groups. These findings indicate that habitual exposure of the lung to either marijuana or cocaine impairs the function and/or cytokine production of AMs. The ultimate outcome of these effects may be an enhanced susceptibility to infectious disease, cancer, and AIDS. PMID- 9372684 TI - Eosinophilic leukocyte accumulation during vagally induced bronchoconstriction. AB - Eosinophilic leukocytes (eosinophils) are important effector cells in allergic inflammatory diseases such as asthma, in which significant accumulation of these cells is observed in the bronchial mucosa. However, there is little information about the relationships between bronchoconstriction and accumulation of eosinophils. We hypothesized that eosinophils are retained in the bronchial vasculature in the inner airway wall during bronchoconstriction because of deformation of the mucosal membrane. To test this hypothesis we induced unilateral bronchoconstriction in open chest guinea pigs by stimulating the right vagus nerve and compared the accumulation of eosinophils in the airway wall of the constricted and contralateral unconstricted lungs using histologic specimens. Results show that the density of eosinophils (number of cells/wall area) significantly increased in the inner wall and decreased in the adventitia of the constricted airways compared with the contralateral unconstricted airways. There was a positive relationship between the amount of smooth muscle shortening and the eosinophil density in the inner wall. On the other hand, this relationship was significantly negative in the adventitia. Atropine completely inhibited the eosinophil accumulation in the inner wall. These data suggest that eosinophils can accumulate in the airway inner wall during bronchoconstriction because of geometrical factors. PMID- 9372685 TI - Airway responsiveness in transgenic mice overexpressing platelet-activating factor receptor. Roles of thromboxanes and leukotrienes. AB - Platelet-activating factor (PAF) is a potent proinflammatory compound potentially involved in the pathogenesis of inflammatory disorders, including bronchial asthma. To elucidate the pathophysiologic roles of PAF in bronchial asthma, we studied airway responsiveness in transgenic mice overexpressing PAF receptor. In the transgenic mice, PAF-induced airway smooth muscle contraction was demonstrated by physiologic and morphometric analyses, whereas there was no significant response in the littermate control group. The PAF-elicited bronchoconstriction in the transgenic mice was significantly reduced not only by a PAF receptor antagonist (WEB-2086) but also by a thromboxane synthesis inhibitor (indomethacin or ozagrel), an inhibitor of 5-lipoxygenase-activating protein (MK-886), or a cysteinyl leukotriene (LT) antagonist (pranlukast). LTB4 receptor antagonist (ONO-4057), however, had no effect on the PAF-induced responses. The transgenic mice showed a bronchial hyperreactivity to methacholine challenge, which was also inhibited by pretreatment with either thromboxane synthesis inhibitor or cysteinyl LT antagonist. These observations suggest that both thromboxane A2 and cysteinyl LTs (LTC4, LTD4, and LTE4) are involved in the bronchial responses to PAF or cholinergic stimulus in mice. The transgenic mice overexpressing PAF receptor may provide an appropriate model to study various PAF related lung diseases, including bronchial asthma. PMID- 9372686 TI - The GM-CSF analogue E21R induces apoptosis of normal and activated eosinophils. AB - There is evidence that eosinophils have an important role in the pathogenesis of allergy and asthma. These cells are regulated by two classes of polypeptides, the colony-stimulating factors, such as granulocyte-macrophage colony-stimulating factor (GM-CSF), and the chemokines, such as RANTES and eotaxin. GM-CSF is involved in the production, survival, and functional activation of eosinophils. RANTES and eotaxin regulate the migration of eosinophils to inflammatory sites, but any effect of these chemokines on eosinophil survival is not known. In this study we demonstrate that although GM-CSF promoted eosinophil survival, the specific GM-CSF analogue E21R induced apoptosis of eosinophils. Apoptosis was observed with unstimulated as well as with chemokine (RANTES and eotaxin) activated eosinophils. Neither RANTES nor eotaxin supported eosinophil survival, and a RANTES antagonist did not affect either cell survival or apoptosis. E21R also induced apoptosis of eosinophils from asthmatic patients. These findings suggest that the GM-CSF receptor may actively control the death as well as the survival of eosinophils, and thus precisely regulate their numbers and activities. Our data also indicate that chemokines are not involved in regulating the lifespan of eosinophils. The introduction of the GM-CSF analogue E21R may offer a novel therapy in inflammatory diseases associated with eosinophil infiltration of different etiologies. PMID- 9372687 TI - Inflammatory cells in the bronchial glands of smokers with chronic bronchitis. AB - To characterize the inflammatory process in the bronchial glands of smokers with chronic sputum production, we examined lobar bronchi from 18 subjects undergoing lung resection for localized pulmonary lesions, all with a history of cigarette smoking. Nine of the subjects had symptoms of chronic bronchitis and chronic airflow obstruction, and nine were asymptomatic, with normal lung function. The number of neutrophils, eosinophils, mast cells, macrophages, CD4+ and CD8+ T lymphocytes, and the ratio of CD4+ to CD8+ cells were assessed in the bronchial glands, epithelium, and submucosa. Cells were identified through immunohistochemistry. Smokers with symptoms of chronic bronchitis had an increased number of neutrophils (p = 0.01) and macrophages (p = 0.03) and a decreased CD4+/CD8+ ratio (p = 0.01) in the bronchial glands as compared with asymptomatic smokers. Chronic bronchitic smokers also had an increased number of epithelial neutrophils (p = 0.04), whereas the numbers of macrophages and CD4+ and CD8+ T-lymphocytes in the epithelium and submucosa were similar in the two groups of smokers. No differences in numbers of eosinophils or mast cells were observed between bronchitic and asymptomatic smokers in any of the compartments examined. In conclusion, smokers with chronic sputum production have an increased infiltration of neutrophils and macrophages and an increased proportion of CD8+ T lymphocytes in their bronchial glands, supporting the important role of bronchial gland inflammation in the pathogenesis of chronic bronchitis. PMID- 9372688 TI - The comet-tail artifact. An ultrasound sign of alveolar-interstitial syndrome. AB - Can ultrasound be of any help in the diagnosis of alveolar-interstitial syndrome? In a prospective study, we examined 250 consecutive patients in a medical intensive care unit: 121 patients with radiologic alveolar-interstitial syndrome (disseminated to the whole lung, n = 92; localized, n = 29) and 129 patients without radiologic evidence of alveolar-interstitial syndrome. The antero-lateral chest wall was examined using ultrasound. The ultrasonic feature of multiple comet-tail artifacts fanning out from the lung surface was investigated. This pattern was present all over the lung surface in 86 of 92 patients with diffuse alveolar-interstitial syndrome (sensitivity of 93.4%). It was absent or confined to the last lateral intercostal space in 120 of 129 patients with normal chest X ray (specificity of 93.0%). Tomodensitometric correlations showed that the thickened sub-pleural interlobular septa, as well as ground-glass areas, two lesions present in acute pulmonary edema, were associated with the presence of the comet-tail artifact. In conclusion, presence of the comet-tail artifact allowed diagnosis of alveolar-interstitial syndrome. PMID- 9372689 TI - Oropharyngeal or gastric colonization and nosocomial pneumonia in adult intensive care unit patients. A prospective study based on genomic DNA analysis. AB - Colonization of the digestive tract has been supposed to be the source of many hospital-acquired infections, especially nosocomial pneumonia. To assess the relationship between oropharyngeal and gastric colonization and subsequent occurrence of nosocomial pneumonia, we prospectively studied 86 ventilated, intensive care unit (ICU) patients. Oropharyngeal or gastric colonizations were detected and quantified on admission and twice weekly during ICU stay. When nosocomial pneumonia was suspected on clinical grounds (new chest X-ray infiltrate and purulent tracheal secretions), diagnosis was assessed on fiberoptic bronchoscopy with quantitative cultures of a protected specimen brush sampling and/or a plugged telescoping catheter sampling yielding > or = 10(3) cfu/ml of at least one microorganism. Bacterial strains responsible for colonization and infection (Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacteriaceae, and Staphylococcus aureus) were compared using pulsed-field electrophoresis. A total of 31 cases (36%) of pneumonia were diagnosed. Oropharyngeal colonization, detected either on admission or from subsequent samples, was a predominant factor of nosocomial pneumonia as compared with gastric colonization. For instance, oropharyngeal colonization with A. baumannii yielded a 7.45-fold estimated increased risk of pneumonia as compared with patients not yet or not identically colonized (p = 0.0004). DNA genomic analysis demonstrated that an identical strain was isolated from oropharyngeal or gastric samples and bronchial samples in all but three cases of pneumonia, due to S. aureus. These findings provide better knowledge of the pathophysiology of nosocomial pneumonia in mechanically ventilated patients. PMID- 9372691 TI - RhDNase I aerosol deposition and related factors in cystic fibrosis. AB - To identify factors influencing lung dose of aerosolized recombinant human deoxyribonuclease (rhDNase I), we used gamma camera and filter techniques to measure deposition in 15 clinically stable patients with cystic fibrosis (CF) (five males and 10 females, age 6-31 yr, mean 16.9) who were on chronic daily therapy. Total and regional deposition were correlated with breathing pattern, pulmonary function, demographic factors, and disease severity. In addition, the effects of each patient's measured lung dose on pulmonary function was estimated by stopping the drug and observing changes in spirometry over a 2-wk follow-up period. After discontinuance of the drug, all patients reported worsening of dyspnea and difficulty producing sputum. There was a significant decrease in FEV1 (% predicted, mean +/- SE, 86.9% +/- 5.57 to 77.8% +/- 5.73, p < 0.005), but all patients completed the study. In some patients, as much as 48% of the deposited aerosol was found in the pharynx (range 0.0 to 0.30 mg, mean 0.089 mg +/- 0.029), and pharyngeal deposition correlated negatively with tidal volume (r = -0.696, p < 0.006) and age (r = -0.743, p < 0.005). For the lungs, deposition ranged between 0.16 mg and 0.78 mg of the 2.5 mg nebulizer dose (mean 0.47 +/- 0.04 mg) and correlated negatively with FEV1 (% predicted, r = -0.611, p = 0.0152). However, the spirometric decrements following cessation of therapy did not correlate with the lung dose of the drug. Analysis of regional deposition within the lungs indicated a wide range of distribution between central and peripheral zones. In conclusion, the deposition pattern of rhDNase I aerosols in patients with CF is largely influenced by respiratory physiology, which itself depends upon age and severity of lung disease. As the patients grow there is a decrease in upper airway deposition and more particles are presented to the lungs where those patients with more airways disease have enhanced pulmonary deposition. Upper airway deposition of rhDNase I is significant, especially in younger patients, and may be related to laryngeal side effects. PMID- 9372690 TI - Near-infrared spectroscopic method for assessing the tissue oxygenation state of living lung. AB - To quantify changes in tissue oxygenation of pathologic lungs, we applied a novel method using near-infrared spectroscopy (NIRs). In in vitro experiments, we assayed the effect of photon scattering on the absorption spectra of an in vitro system simulating structures of lung, which consists of test tube containing air in hematocrit tubes and red blood cell suspension with various predetermined hemoglobin concentrations. It was determined that photon scattering of the tissue containing air did not affect the absorption in the NIR region. In in vivo experiments, we tested the applicability of the NIRs technique in rat lungs under the following conditions: (1) hypoxic loading; (2) administration of an inhibitor (NaCN) of the mitochondrial respiratory chain; (3) hemorrhagic shock. We found that: (1) Changes in hemoglobin oxygenation state in the lung measured by NIRs depended on inspired oxygen concentrations; (2) NaCN-induced reduction of cytochrome oxidase a,a3 in the lung was observed; and (3) Total hemoglobin levels in the lung decreased after bleeding. Changes in the hemoglobin oxygenation state and cytochrome oxidase redox state in the lung were determined using the least square-curve fitting for NIR absorption spectra. Our NIRs technique was capable of assessing the hemoglobin oxygenation and cytochrome oxidase redox state in the lung. PMID- 9372692 TI - A prospective study of patients with lung cancer and hyponatremia of malignancy. AB - This study was undertaken to define the impact of arginine vasopressin (AVP) and atrial natriuretic peptide (ANP) on sodium homeostasis in patients with lung cancer. Patients had their serum and urine electrolytes and osmolality determined before and after a saline infusion of 500 ml. The plasma hormones, AVP, ANP, plasma renin activity (PRA), angiotensin II, and aldosterone were determined by radioimmunoassay every 15 min before, during and after the saline infusion. Fifty patients, 31 with small cell lung cancer and 19 with non-small cell lung cancer participated in this trial. All 11 patients (10 patients with small cell lung cancer and one patient with non-small cell lung cancer) who presented with hyponatremia had inappropriately elevated levels of AVP. Elevated plasma AVP levels were highly correlated with the presence of hyponatremia (p < 0.00001). Initial plasma ANP levels were not associated with hyponatremia (p = 0.73). Urinary sodium concentration increased during the saline infusion proportional to the initial plasma level of ANP (p = 0.0045). AVP appears to be elevated in nearly all patients with hyponatremia of malignancy. ANP plasma levels in patients with lung cancer are associated with the ability to excrete a sodium load but do not appear to downregulate renin, angiotensin II, and aldosterone production. PMID- 9372693 TI - Effects of proteinosis surfactant proteins on the viability of rat alveolar macrophages. AB - Pulmonary alveolar proteinosis (PAP) is a disease of unknown etiology that is characterized by the accumulation of protein- and lipid-rich insoluble material in alveoli and terminal bronchioles of the lung. Alveolar macrophages (AM) in PAP are reportedly extremely large and have low viability. We investigated substances in lavaged lung material from patients with PAP that induced these cellular changes in rat AM. Rat AM were incubated for various periods with liposomes prepared from lipids and isolated hydrophobic surfactant apoproteins, and cell size, viability, and lactate dehydrogenase release were determined. Of the hydrophobic apoproteins, a dimeric form of surfactant-associated protein-C ([SP C]2) had the most marked effects. In addition, [SP-C]2 induced increased superoxide anion release at an early phase (6 to 12 h) and an increase in glutathione content at 24 h of incubation. At 3 d after incubation, cellular glutathione and adenosine triphosphate (ATP) content were significantly decreased in cells treated with [SP-C]2, [SP-C]2 was presumed to cause early cell death through increased formation of superoxide anion and the subsequent derangement of cellular metabolism. [SP-C]2 was not removed from cells, and SP-B and SP-C were removed at slower rates than lipids. The changes in macrophages induced by [SP C]2 may contribute to establishing PAP. PMID- 9372694 TI - Circulating levels of soluble interleukin-6 receptor in patients with bronchial asthma. AB - In the search for markers of airway inflammation, we investigated the role of soluble interleukin-6 receptor (sIL-6R) in patients with bronchial asthma. Serum levels of sIL-6R were measured in 20 patients with stable asthma and in 18 healthy control subjects by means of a sandwich enzyme-linked immunosorbent assay. Such levels were also evaluated during a spontaneous attack of asthma (n = 10) as well as that after allergen inhalation (n = 7). Results were compared with those observed during the stable state and after the inhalation of methacholine. Serum levels of sIL-6R in asthmatic patients (132 +/- 31 ng/ml) significantly exceeded those of control subjects (111 +/- 16 ng/ml) (p < 0.05). These levels showed no correlation with such clinical variables as nonspecific bronchial hyperreactivity, atopic status, or serum concentration of IgE. Serum sIL-6R levels observed during an asthmatic attack versus those during the stable state (4 wk later) differed significantly. After a severe attack of asthma, such levels were significantly elevated on the second and third days, but not on Day 5. After challenge, circulating levels of sIL-6R were significantly increased 24 h after the inhalation of allergen but not of methacholine. Results suggest that serum levels of sIL-6R are increased in patients with asthma and are further increased during a spontaneous attack or that provoked by the inhalation of allergen. Thus, serum sIL-6R may reflect inflammation of the airway. Further studies are indicated to determine the clinical significance and the application of serum levels of sIL-6R in evaluating asthmatic patients. PMID- 9372695 TI - Factors influencing indoor concentrations of nitric oxide in a Parisian intensive care unit. AB - In low concentrations, inhaled nitric oxide (NO) increases arterial oxygenation in patients with severe acute respiratory distress syndrome. When present in the ambient atmosphere, NO and its oxidative derivate, nitrogen dioxide (NO2), are considered pollutants. The aim of this study was to assess whether the administration of inhaled NO to mechanically ventilated patients was associated with an increased risk of exposure to NO and NO2 for medical and paramedical staff. During a 1-yr period, indoor and outdoor NO and NO2 concentrations were measured using chemiluminescence in a 14-bed intensive care unit (ICU) to assess the possible influence of therapeutic NO administration on indoor pollution. Ambient concentrations of NO within the ICU were 237 +/- 147 parts per billion (ppb) during periods of NO administration and 289 +/- 147 ppb during periods without NO administration (mean +/- SD, NS). Indoor concentrations of NO and NO2 were entirely dependent on outdoor concentrations and were mainly influenced by climatic conditions such as atmospheric pressure, mass of clouds, and speed of the wind. Therapeutic administration of concentrations of inhaled NO < or = 5 ppm to critically ill patients did not affect the ambient concentration of NO and NO2 within the ICU, which was mainly dependent on the outdoor air pollution. As a consequence, scavenging of exhaust NO from the breathing circuit in the ventilator does not appear mandatory in ICUs located in areas with significant urban pollution when NO concentrations < or = 5 ppm are administered. PMID- 9372696 TI - Simulation of cough in man by magnetic stimulation of the thoracic nerve roots. AB - Normal cough requires abdominal muscle contraction. We have previously reported contraction of the abdominal muscles elicited by a single percutaneous magnetic stimulation of the thoracic nerve roots. We hypothesized that paired magnetic twitches could generate sufficient tension in the abdominal muscles to simulate cough. Therefore, six normal subjects were stimulated at the T10 intervertebral level in the seated position. We measured the gastric pressure elicited by paired magnetic stimuli (pTw Pga) with interstimulus intervals in the range of 10 ms (100 Hz) to 999 ms (1 Hz). In the second part of the study we evaluated paired stimuli (at the frequency found to produce the greatest response) using a valve to simulate the function of the glottis; the valve was arranged such that it opened once mouth pressure exceeded a predetermined threshold. Mean pTw Pga during stimulation for the 6 subjects was 74 cm H2O (range, 30-109), and mean peak flow was 209 L/min (range, 128-345 L/min). These values were increased if the subject took a prior inspiration or had previously made a vigorous expiratory effort. Comparable values for a maximal natural cough were 212 cm H2O and 649 L/min. We conclude that paired magnetic thoracic nerve root stimulation produces gastric pressure and expiratory flow of an order of magnitude comparable to a natural cough. PMID- 9372697 TI - Smoker's lung transplanted to a nonsmoker. Long-term detection of smoker's macrophages. AB - Alveolar macrophages (AM) from smokers contain characteristic smoker's inclusion bodies within the cytoplasm as a result of ingestion of substances in the inhaled smoke. How long these smoking-related changes in the AM population can be seen after smoking cessation is largely unknown. We had the unique opportunity to investigate a 51-yr-old never-smoker after single lung transplantation (TX) for alpha 1-antitrypsin deficiency emphysema who received a donor's lung from a heavy cigarette smoker. Serial bronchoalveolar lavage (BAL) was performed in the donor's lung for transplant surveillance at defined time intervals, and the percentage of AM with characteristic smoker's inclusions was counted on slides stained with May-Grunwald-Giemsa stain. The patient had an uneventful course after TX with no major infectious complications or episodes of rejection. One month after TX the percentage of smoker's AM was 98%. BAL after 2, 5, 7, and 12 mo showed a similar high percentage. After 18 mo a first a decrease was seen, down to 78%, and after 2 yr a decrease to 59% was seen. After 3 yr, the smoker's AM had mostly disappeared, only 3% were still present. In conclusion, smoker's inclusions in AM may be detected for at least 2 yr after smoking has ceased, which is considerably longer than the estimated life span of the AM. PMID- 9372698 TI - Effect of inhaled indomethacin on exercise-induced bronchoconstriction in children with asthma. PMID- 9372699 TI - Lidocaine and oral mexiletine block reflex bronchoconstriction in asthmatic subjects. PMID- 9372700 TI - An epiphany in retrospect. PMID- 9372701 TI - Look-alike abbreviations: prescriptions for confusion. PMID- 9372702 TI - In search of a delegation model. PMID- 9372703 TI - Transdermal fentanyl for chronic pain. PMID- 9372704 TI - Medicinal use of marijuana. PMID- 9372705 TI - Two-in-one tablet eases 'pill burden'. PMID- 9372706 TI - The nurse as wise, skillful, and compassionate stranger. PMID- 9372707 TI - 10 keys to quality care. PMID- 9372708 TI - Nurses at the bedside. PMID- 9372709 TI - Clinical snapshot: multiple sclerosis. PMID- 9372710 TI - Identifying nonischemic causes of life-threatening arrhythmias. PMID- 9372711 TI - Emergency! Pheochromocytoma. PMID- 9372712 TI - Defining standards for end-of-life care. PMID- 9372713 TI - Common questions about ileoanal reservoirs. PMID- 9372714 TI - Medicare reimbursement: a victory for APRNs. PMID- 9372716 TI - Argon vs diode laser trabeculoplasty. AB - PURPOSE: To compare the efficacy of diode laser and argon laser trabeculoplasty in a randomized prospective study of 11 paired fellow eyes. METHODS: Fellow eyes of 11 patients, having had no prior laser trabeculoplasty and requiring laser trabeculoplasty to lower intraocular pressure, were randomly assigned prospectively to diode laser trabeculoplasty in one eye and argon laser trabeculoplasty in the other eye. RESULTS: In the diode laser group, the average baseline intraocular pressure was 21.6 +/- 2.0 mm Hg before trabeculoplasty and 19.6 +/- 2.1 mm Hg (or a 7.7% +/- 11.5% mean pressure reduction) at 1 month, 19.3 +/- 2.6 mm Hg (or a 6.9% +/- 13.5% mean reduction) at 2 months, and 19.0 +/- 3.3 mm Hg (or a 2.4% +/- 16.9% mean reduction) at 3 months postoperatively. In the argon laser group, the average intraocular pressure was 24.4 +/- 3.5 mm Hg before treatment and 17.6 +/- 1.7 mm Hg (or a 24.7% +/- 11.4% mean pressure reduction) at 1 month, 16.8 +/- 2.5 mm Hg (or a 26.7% +/- 15.3% mean reduction) at 2 months, and 15.5 +/- 1.2 mm Hg (or a 30.0% +/- 16.5% mean reduction) at 3 months after laser trabeculoplasty. The difference between argon and diode laser intraocular pressure reduction was statistically significant at 1 month (P < .01), 2 months (P < .01), and 3 months (P < .05) after treatment. CONCLUSION: Argon laser trabeculoplasty appears to be more effective than diode laser therapy in lowering intraocular pressure during the first 3 months after treatment. PMID- 9372715 TI - Persistent fetal vasculature (PFV): an integrated interpretation of signs and symptoms associated with persistent hyperplastic primary vitreous (PHPV). LIV Edward Jackson Memorial Lecture. PMID- 9372717 TI - Ultrasound biomicroscopic findings in humans with shallow anterior chamber and increased intraocular pressure after the prone provocation test. AB - PURPOSE: To investigate ultrasound biomicroscopic findings in human eyes with shallow anterior chamber and risk of anterior chamber angle-closure glaucoma after the prone provocation test. METHODS: A total of 32 consecutive patients (64 eyes) with bilateral shallow anterior chamber who were at risk for primary angle closure glaucoma underwent the prone provocation test in a lit room. Before and immediately after measurement of intraocular pressure in this test, high frequency ultrasound biomicroscopy was performed in the horizontal and vertical directions, and the chamber angle views were recorded at the 3-, 6-, 9-, and 12 o'clock positions. RESULTS: Ten eyes of six patients exhibited an increase in intraocular pressure of 8 mm Hg or more, a positive response, with the remainder showing a negative response to the test. In the eyes with a positive response to the test, the profile of the iris showed a markedly convex shape with a large space behind the posterior iris. However, the anterior chamber angle of each eye remained open, even during the high level of intraocular pressure caused by the provocation. CONCLUSIONS: The present results suggest that no angle closure occurs during the initial increase of intraocular pressure after the prone provocation test. Such an initial increase of intraocular pressure was associated with high pressure in the posterior chamber because of the relative pupillary block. A time lag was observed between the high intraocular pressure caused by the pupillary block and the occurrence of angle closure. PMID- 9372718 TI - Nonarteritic anterior ischemic optic neuropathy: time of onset of visual loss. AB - PURPOSE: To study time of day and seasonal variation of onset of visual loss in nonarteritic anterior ischemic optic neuropathy (AION). METHODS: From 1975 to 1995, we prospectively investigated the time of discovery of visual loss in 635 patients (871 eyes) with AION--a total of 925 episodes. Data were analyzed for two variables: time of day of discovery of visual loss for 544 episodes and seasonal variation of the onset of AION for 839 episodes. RESULTS: Of 544 episodes, time of day for discovery of visual loss was upon awakening from sleep in the morning or a nap in 282 (51.8%), during the first opportunity to use vision critically early in the morning in 117 (21.5%), and later in the day in 145 (26.7%). AION was significantly (P = .0030) more frequent in summer than winter. Estimated monthly onset rates were 82.7 episodes (95% confidence interval [CI], 71.3 to 95.8) in summer, 58.3 (95% CI, 48.9 to 69.6) in winter, 66.0 (95% CI, 55.9 to 77.9) in spring, and 72.7 (95% CI, 62.1 to 85.1) in fall. Onset significantly (P < .0001) occurred more during hot than cold months, with the estimated monthly rate of onset in hot months of 82.2 episodes (95% CI, 73.7 to 91.8) compared with 59.8 (95% CI, 53.3 to 67.1) in cold months. CONCLUSIONS: In at least 399 (73.3%) of 544 episodes of AION, patients discovered visual loss upon first awakening or at first opportunity to use vision critically after sleeping, suggesting that nocturnal arterial hypotension may play an important role. Also, AION developed more often in summer than in winter. PMID- 9372719 TI - Clinical assessment of the macula by retinal topography and thickness mapping. AB - PURPOSE: To report a quantitative and objective method for assessing pathologic alterations in retinal structures to improve the evaluation of macular diseases. METHODS: We used a system based on the scanning retinal thickness analyzer to generate serial optical section images of the retina and provide mapping of the retinal topography and thickness in a normal subject and in patients with representative maculopathies including traumatic macular hole, central serous chorioretinopathy, branch retinal vein occlusion, diabetic macular edema, and retinal pigment epithelial detachment. RESULTS: The effectiveness of the system in imaging both the vitreoretinal and chorioretinal interfaces was confirmed in the normal subject and in patients with various maculopathies. Mapping of retinal topography and thickness in a normal eye correlated well with normal anatomy, delineating the foveal depression clearly. The retinal thickness map in a patient with diabetic macular edema showed thickening of the retina and absence of a foveal depression. The patients with central serous chorioretinopathy and branch retinal vein occlusion had an elevated vitreoretinal surface. Conversely, the patient with retinal pigment epithelial detachments had a relatively flat vitreoretinal interface but an irregularly elevated chorioretinal surface. CONCLUSION: Quantitative mapping of retinal topography and thickness is a promising tool that may improve evaluation of macular diseases. PMID- 9372720 TI - Orbital hemangiopericytoma: clinical and morphologic features. AB - PURPOSE: To report the clinical and histopathologic features of orbital hemangiopericytoma. METHOD: We review the clinical and histopathologic features in seven patients. RESULTS: Ultrasonography, computed tomography, and magnetic resonance imaging defined the location and extent of the tumor in each patient but did not disclose pathognomonic features for the specific diagnosis of hemangiopericytoma. The predominating histopathologic feature of each tumor was a mixed pattern of ovoid cells and sinusoidal space formations. Five patients showed mild to severe cellular atypia; three had obvious pleomorphism and increased number of abnormal mitotic figures. Tumor cells disclosed cytoplasmic reactivity for vimentin but in five cases were negative for other immunologic markers. Six patients received surgical treatment with an attempt for total removal of the tumor; one had biopsy and radiation therapy. In two patients, radiation therapy was given in addition to tumor removal with orbital exenterations. Three patients died with recurrent and metastatic disease, and four patients are alive without tumor for a follow-up period ranging from 3 to 9 years. CONCLUSIONS: Orbital hemangiopericytoma may behave as a malignant tumor, leading to local recurrence or metastasis, or both. Clinical and histopathologic findings should be considered jointly to evaluate the clinical course; histopathologic findings alone are not sufficient to predict the biologic behavior of this tumor. PMID- 9372721 TI - Screening for resistance to activated protein C and the mutant gene for factor V:Q506 in patients with central retinal vein occlusion. PMID- 9372722 TI - A hemodynamic model of the pathogenesis of age-related macular degeneration. AB - The clinical message of this editorial is that age-related macular degeneration may be a vascular disorder. It may be a manifestation of the hemodynamic consequence of the process of lipoid infiltration that, when it involves other organs such as those of the cardiovascular or cerebrovascular systems, is called atherosclerosis. The hemodynamic model presented here postulates that in age related macular degeneration, the increase in resistance to the flow of blood in the choroid is caused by an age-related and diet-related decrease in the compliance of the sclera. It proposes that the form of age-related macular degeneration produced may depend on the relative resistances of the ophthalmic and cerebral circulations. A decrease in perfusion, leading to the atrophic form of age-related macular degeneration, is the outcome if the resistance of the cerebral circulation is relatively lower than that of choroid. Conversely, a relatively greater increase in the increase in the hydrostatic pressure in the choroidal vessels, leading to the exudative form of the disorder. PMID- 9372724 TI - Association of pseudoexfoliation syndrome with increased vascular risk. AB - PURPOSE: To examine vascular associations with pseudoexfoliation syndrome in view of the wide-spread elastosis now demonstrated in this disorder that affects many tissues, including vessel walls. METHODS: The Blue Mountains Eye Study is a population-based study of eye disease in an area west of Sydney, Australia. Of 4433 eligible persons aged 49 years or older, 3,654 (82.4%) participated. Signs of pseudoexfoliation were graded clinically, after excluding 108 people who had bilateral cataract surgery. RESULTS: Pseudoexfoliation was present in 81 (2.3%) of 3546 participants aged 49 years or older. The prevalence of pseudoexfoliation increased with age and was higher in women and in people with glaucoma. Pseudoexfoliation was statistically significantly associated with a history of angina or hypertension or a combined history of angina, acute myocardial infarction, or stroke. CONCLUSION: Slit-lamp signs of pseudoexfoliation may identify individuals with an increased vascular risk. PMID- 9372723 TI - Adverse side effects associated with latanoprost. AB - PURPOSE: To report three different adverse reactions after initiating treatment with latanoprost. METHOD: Serial clinical examinations of three patients were performed. RESULTS: Adverse reactions such as ocular hypotony and choroidal effusions, recurrent cystoid macular edema, and facial rash were noted to occur within 1 to 4 weeks after starting topical latanoprost for the treatment of primary open-angle glaucoma. CONCLUSION: Clinicians should be alerted to these possible complications of topical latanoprost therapy. PMID- 9372725 TI - Peripheral retinal neovascularization and retinal vascular occlusion associated with activated protein C resistance. AB - PURPOSE: To describe a patient with peripheral retinal neovascularization and vascular occlusion associated with activated protein C resistance. METHODS: Case report. A 63-year-old woman was examined for acute loss of vision in both eyes. She was noted to have macular edema in both eyes as well as a macular branch vein occlusion in the right eye and a central retinal vein occlusion in the left eye. Peripheral retinal neovascularization was present in both eyes. RESULT: Extensive systemic evaluation disclosed a heterozygous state for the factor V Leiden indicating activated protein C resistance. CONCLUSION: Activated protein C resistance may be associated with peripheral retinal neovascularization. PMID- 9372726 TI - Retinal arterial occlusion in a child with factor V Leiden and thermolabile methylene tetrahydrofolate reductase mutations. AB - PURPOSE: To analyze the potential cause of retinal arterial occlusion in a 9-year old child. METHODS: Case report. Antithrombin III, protein C, free protein S, activated protein C resistance, and antiphospholipid antibodies in plasma were determined. Determination of factor V R506Q (Leiden mutation), thermolabile methylene tetrahydrofolate reductase by polymerase chain reaction, and restriction enzyme analysis were performed. RESULTS: The patient was found to be heterozygous for factor V R506Q (Leiden mutation) and homozygous for thermolabile methylene tetrahydrofolate reductase. CONCLUSION: Coexistence of two mild hereditary thrombophilic states may result in severe thrombotic manifestations in young people. PMID- 9372727 TI - Management of condensation on a foldable acrylic intraocular lens after vitrectomy and fluid-air exchange. AB - PURPOSE: To describe the management of condensation on the posterior surface of a foldable acrylic intraocular lens during vitrectomy and fluid-air exchange. METHODS: A 70-year-old pseudophakic man with a foldable acrylic intraocular lens and open posterior capsule underwent vitrectomy and fluid-air exchange for repair of rhegmatogenous retinal detachment. RESULTS: During pars plana vitrectomy and fluid-air exchange, condensation immediately formed on the posterior surface of the foldable acrylic intraocular lens. This condensation, which prevented a view of the retina, was eliminated by wiping the posterior surface of the intraocular lens with a soft-tipped cannula. CONCLUSION: Although condensation may rapidly form on acrylic intraocular lenses during vitrectomy and fluid-air exchange, it can be managed readily by wiping with a soft-tipped cannula. PMID- 9372728 TI - Intracameral urokinase for dissolution of fibrin or blood clots after glaucoma surgery. AB - PURPOSE: To report the use of intracameral urokinase for dissolving fibrin or blood clots after glaucoma surgery. METHODS: Four eyes of four patients who had undergone glaucoma surgery developed an anterior chamber fibrin or blood clot and increased intraocular pressure. Urokinase was injected into the anterior chamber in each patient to dissolve the clot. RESULTS: In all cases, urokinase injection resulted in reduction of intraocular pressure. No adverse effects of urokinase injection were detected during the short follow-up period. CONCLUSIONS: Urokinase may be a safe, inexpensive, and convenient alternative to tissue plasminogen activator for dissolving fibrin or blood clots after glaucoma surgery. Additional studies are warranted to evaluate the long-term safety of intracameral injection. PMID- 9372729 TI - A pars plana approach for cataract surgery in posterior lenticonus. AB - PURPOSE: To report the management and outcome of cataract surgery and intraocular lens placement in a child with unilateral posterior lenticonus. METHODS: Case report. A 7-year-old boy with a best-corrected visual acuity of RE, 20/200, posterior lenticonus, and cataract underwent a pars plana lensectomy, vitrectomy, posterior chamber intraocular lens insertion into the ciliary sulcus, and central anterior capsulotomy. RESULT: At 2 years of follow-up, best-corrected visual acuity was RE, 20/40. CONCLUSION: This technique allowed complete removal of the opaque posterior lenticonus plaque while preserving the peripheral anterior capsule for sulcus fixation of the posterior chamber intraocular lens. PMID- 9372731 TI - Dehydration injury as a possible cause of visual field defect after pars plana vitrectomy for macular hole. AB - PURPOSE: To present the hypothesis that a visual field defect after pars plana vitrectomy for macular hole may be caused by dehydration injury to the nerve fiber layer during the fluid-air exchange. METHODS: In a consecutive nonrandomized series of 45 operations on 35 eyes of 34 patients with full thickness macular hole, the surgical method was changed with postoperative visual field testing performed. RESULT: The incidence and location of the post-operative visual field defect was affected only by changing the location of the infusion cannula. CONCLUSION: Dehydration injury of the nerve fiber layer during the fluid air exchange should be considered as a possible cause of visual field defect after pars plana vitrectomy for macular hole. PMID- 9372730 TI - Transient shallow anterior chamber induced by supraciliary fluid after vitreous surgery. AB - PURPOSE: To report the mechanism of transient shallow anterior chamber after vitreous surgery for proliferative diabetic retinopathy. METHOD: Using ultrasound biomicroscopy, we examined a patient with transient shallow anterior chamber after vitreous surgery for proliferative diabetic retinopathy. RESULTS: On the day after surgery, slit-lamp examination disclosed a shallow anterior chamber that persisted for 1 week and deepened thereafter. Ultrasound biomicroscopy 5 days postoperatively disclosed a narrow angle in the peripheral anterior chamber and supraciliary fluid. At 14 days postoperatively, suprachoroidal fluid could not be detected, and the angle was wide. CONCLUSION: The shallow anterior chamber in this patient was caused by supraciliary fluid after vitreous surgery. PMID- 9372733 TI - Purtscher-like retinopathy after uncomplicated administration of retrobulbar anesthesia. AB - PURPOSE: To report a case of Purtscher-like retinopathy after administration of retrobulbar anesthesia for an otherwise uncomplicated cataract extraction. METHOD: Case report. RESULTS: After cataract surgery with retrobulbar anesthesia, the patient followed a typical course of Purtscher-like retinopathy with an initial severe loss of vision followed by a gradual and nearly complete improvement in visual function. CONCLUSIONS: Purtscher-like retinopathy is uncommon after administration of retrobulbar anesthesia but had the same clinical course as other causes of this disorder. PMID- 9372732 TI - Macular ischemia as a cause of decreased vision in a patient with acquired immunodeficiency syndrome. AB - PURPOSE: To report macular ischemia as a cause of decreased vision in a patient with acquired immunodeficiency syndrome (AIDS). METHODS: A 50-year-old man with AIDS who had previously diagnosed human immunodeficiency virus retinopathy and peripheral cytomegalovirus retinitis was initially examined with decreased vision in both eyes. He underwent complete systemic and ocular evaluation, fundus photography, and fluorescein angiography. RESULT: Fluorescein angiography disclosed irregular enlargement of the foveal avascular zone in both eyes. CONCLUSIONS: Macular ischemia may cause decreased vision in patients with AIDS and can be detected by fluorescein angiography. PMID- 9372734 TI - Optic neuritis after influenza vaccination. AB - PURPOSE: To present evidence for a causal relation between optic neuritis and influenza vaccination. METHODS: Case report. In a 59-year-old woman with bilateral optic neuritis, neuro-ophthalmologic examination, magnetic resonance imaging, fluorescent treponemal antibody absorption test, antinuclear antibodies, and complete blood cell count and chemistry were performed. RESULTS: Our patient developed bilateral optic neuritis on two occasions, 1 year apart. No evidence of neuroretinitis, syphilis, or systemic lupus erythematosus was identified. Influenza vaccination was given 2 weeks before the onset of each episode. CONCLUSION: This case provides compelling clinical evidence that implicates influenza vaccination as a cause of optic neuritis. PMID- 9372736 TI - Discoid lupus erythematosus presenting as asymmetric posterior blepharitis. AB - PURPOSE: To describe the ophthalmic findings of patients with discoid lupus erythematosus. METHOD: We describe two women who originally were thought to have asymmetric posterior blepharitis; however, the involved eyelid also had an erythematous, scaly cutaneous lesion. RESULT: In both patients, histology and immunofluorescence studies performed on cutaneous biopsy specimens established the diagnosis of discoid lupus erythematosus. CONCLUSIONS: It is important to diagnose discoid lupus of the eyelids because misdiagnosis can delay treatment and thus lead to deformities of the eyelid margin. Misdiagnosis can also lead to a complicated full-thickness eyelid biopsy and delay the diagnosis of systemic lupus erythematosus. PMID- 9372735 TI - Optic nerve hypoplasia secondary to intracranial teratoma. AB - PURPOSE: To postulate a causal relation between optic nerve hypoplasia and a suprasellar teratoma. METHOD: Case report. RESULTS: A 6-month-old infant with suprasellar teratoma was visually inattentive and had searching nystagmus. He had moderately severe, bilateral optic nerve hypoplasia with the left eye being somewhat worse than the right eye. CONCLUSIONS: Optic nerve hypoplasia is a major cause of impaired vision in children and rarely has been attributed to an intracranial tumor. Our case, involving a patient with a suprasellar teratoma and optic nerve hypoplasia, supports a causal relation between the two. PMID- 9372737 TI - Reduction in the area of the anterior capsule opening after polymethylmethacrylate, silicone, and soft acrylic intraocular lens implantation. PMID- 9372738 TI - Protocol for the examination of specimens removed from patients with carcinoma of the exocrine pancreas: a basis for checklists. Cancer Committee, College of American Pathologists. PMID- 9372739 TI - Shattuck Lecture--outcomes management. A technology of patient experience. 1988. PMID- 9372740 TI - The quality of care. How can it be assessed? 1988. PMID- 9372741 TI - College of American Pathologists Foundation Conference VIII on patient-centered pathology practice--outcomes and accountability. Overview, glossary, and bibliography. PMID- 9372742 TI - The nature and extent of training activities in clinical pathology required for effective consultation on laboratory test selection and interpretation. AB - OBJECTIVE: The goal of this study was to identify the activities in clinical pathology training and the length of time required in each to effectively train residents as consultants on laboratory test selection and interpretation. METHODS: The information needed to address these questions was obtained from a study of 20 residents in clinical pathology at our institution between 1990 and 1996. In the survey participants were asked to assess the value of specific training activities in developing their confidence when addressing consultative questions on laboratory test use and interpretation. Participants were also asked to assess the length of time required to gain confidence in performing this role. RESULTS: The results of the study demonstrate that confidence in providing advice on clinical laboratory test selection and interpretation is acquired to a significant but not absolute degree after an intense 8-week experience in a single clinical laboratory subspecialty, during which time no other responsibilities are assigned. The data also indicate that interactions with clinical pathologists and formal lectures provided to the trainees during their rotations are critical components of the consultation service. There was a significant decrease in the length of time required to provide effective information on test selection and interpretation as the residents progressed through their training. CONCLUSIONS: For all of the major subspecialties in clinical pathology, the residents gained significant confidence by 4 weeks of intense training, and by 8 weeks participants were very confident in answering consultation questions. Even after 8 weeks, however, fewer than 10% of the residents felt absolutely confident in their own decisions regarding laboratory test use and interpretation prior to discussion with senior residents and faculty. Thus, acquisition of expertise to effectively provide advice on laboratory test selection and interpretation required up to 8 weeks of focused training in each clinical laboratory subspecialty. Gaining confidence in multiple areas requires a significant commitment of full-time training. This study provides an understanding of the type and extent of training required to attain the skills necessary to effectively provide consultation in clinical pathology. PMID- 9372743 TI - Laboratory practices for reporting bacterial susceptibility tests that affect antibiotic therapy. AB - OBJECTIVE: To evaluate a laboratory-based process for integrating antimicrobial susceptibility, pharmacy, and clinical data with rapid physician notification to improve the care and outcome of patients with bacterial infections. DESIGN: Randomized case control study comparing standard microbiology reporting method with a targeted notification procedure. RESULTS: Of 254 cases studied, a discordance between antimicrobial susceptibility test results and antibiotic therapy was detected in 140 (55%) patients and confirmed after clinical review in 49 (19%). Appropriate changes in antibiotic therapy were made significantly sooner and in a significantly higher proportion of cases with targeted notification than with standard reporting procedures. CONCLUSIONS: Utilization of antimicrobial susceptibility results is improved by integrating clinical and therapeutic information to identify cases that require physician notification, as measured by the timeliness and appropriateness of antibiotic treatment. PMID- 9372744 TI - Clinically relevant breast cancer reporting: using process measures to improve anatomic pathology reporting. AB - OBJECTIVE: Breast cancer reports form an important part of the basis of clinical decision making for patients. Our objectives were to improve breast cancer reporting in the Urban Central Region in Utah of Intermountain Health Care in a clinically relevant manner and to show that the method chosen actually improved information transfer among physicians of breast cancer patients and led to durable changes in pathologist behavior. METHODS/INTERVENTION: Pathologists designed a synoptic report based on interviews with oncologists about what data were meaningful. The report format was piloted with one hospital pathology group, modified, and implemented in three hospitals. A report evaluation of missing information was done before, immediately after, and 2 years after the intervention. Oncologists were surveyed after 2 years to evaluate satisfaction with report format. RESULTS: Changing breast cancer reporting to a synoptic format significantly decreased information missing from pathology reports. Prior to implementation, 32 of 365 reports lacked some item(s) of pathology information desirable to clinicians; after the intervention, 8 of 250 reports contained missing information. After 2 years, 1 in 190 reports contained missing data elements. Synoptic breast cancer reports continued to be used by pathologists throughout the reporting period. Oncologists responding to a survey reported uniform satisfaction with the new reporting format. SUMMARY: Pathologists are important members of the clinical oncology team. They provide patient-specific information crucial to patient care. Activities designed to improve the quality of reporting processes should use clinically relevant indicators of process improvement, such as measurement of missing information and satisfaction of clinical colleagues with format/quality of information. PMID- 9372746 TI - Outcomes management. New opportunities in a shrinking pathology market. AB - With the increasing prevalence of managed care, the short-term and long-term outlook for the pathology workforce has changed dramatically for the worse. Among the many new opportunities that are available for pathologists, one of the most significant is outcomes management. Outcomes management is a natural evolution for pathologists and requires skills that are typically found in well-respected practicing pathologists. One example of a pathologist-led department of outcomes management is presented. PMID- 9372745 TI - Outcomes and informatics. AB - OBJECTIVE: To provide an overview of the potential contribution that informatics can make for pathologists who become involved in outcomes assessment and management. DATA SOURCES: Contemporary scientific articles centered on pathologists and the assessment of outcomes, the definitions of outcomes assessment and management, and related methodologic issues, especially those pertaining to information technology and outcomes, and a summary of eight independent group process sessions involving volunteer pathologists and a group facilitator discussing issues related to informatics and outcomes as structured by a clinical scenario with focusing questions. STUDY SELECTION: Articles reviewed were drawn primarily from the literature published since 1985 and found through Medline key word searches of titles and abstracts; likely articles were then selected for subsequent detailed review on the basis of the abstract's contents. Group process data were drawn from summaries of each of the eight groups as prepared by the facilitator from notes taken during the session by a designated scribe. CONCLUSIONS: It is crucial for pathologists to participate in clinical outcomes studies. Informatics can serve as a tool kit for performing outcomes studies relevant to pathology (eg, collect data or analyze data), or it can be seen as a malleable component of health care processes that can be modified to achieve improved outcomes. Pathologists see many potential avenues for using informatics to leverage the impact that the pathologist and laboratory can have on clinical outcomes. Focusing on some specific informatics learning objectives can help the pathologist become a leader in outcomes studies. PMID- 9372747 TI - Projecting corporate health plan utilization and charges from annual ICD-9-CM diagnostic rates: a value-added opportunity for pathologists. AB - OBJECTIVE: To develop an allocation method for corporate health plan resources and expenditures based on annual International Classification of Disease, 9th revision, Clinical Modification (ICD-9-CM) diagnostic rate stratification as a surrogate for disease incidence. DESIGN: A data-mining process was applied to a self-insured corporate health plan database. Annual membership rates of Current Procedural Terminology (CPT) procedure utilization and charges between 1990 and 1994 for a cohort of 7216 continuously employed plan members were stratified according to the annual rates of the 19 major ICD-9-CM diagnostic classifications. The stratified annual CPT utilization and charge rates were analyzed by correlation analysis and one-tailed t test. RESULTS: Laboratory and pathology procedure utilization and charge rates were highly correlated with specific rankings of ICD-9-CM diagnostic classifications. The health plan diagnostic rate, laboratory utilization rate, and all charge rates increased significantly during the 5 study years. CONCLUSION: Although all procedure utilization and charge rates in this health plan increased each year, their proportionality consistently was maintained among diagnostically related groups of patients. By restraining global expenditures, managed health plans conflict with historical utilization and charge patterns. Treating ICD-9-CM diagnostic groups as disease management services within a managed care plan allows procedures and expenses to be allocated according to medical necessity in the context of total membership benefits. For pathologists, who recently were mandated by the Health Care Financing Administration and the Office of Inspector General of the Department of Health and Human Services to become stewards of ICD 9-CM coding, this is a unique opportunity to lead an initiative to perfect managed care. The process will require permanent patient numbers, computerized longitudinal patient records, and standardized coded medical terminology. PMID- 9372748 TI - Mucinous tumors of the ovary: interobserver diagnostic variability and utility of sectioning protocols. AB - OBJECTIVES: To determine the interobserver variability of the subclassification of ovarian mucinous tumors and the utility of different sectioning protocols. METHODS: Six pathologists retrospectively reclassified 73 mucinous tumors (30 adenomas, 22 low malignant potential tumors, and 21 carcinomas). Using probabilities, the accuracy of limited sectioning protocols was compared with that of a one section per centimeter protocol. RESULTS: The mean kappa statistic was 0.56, indicating only good agreement. Although a limited sectioning protocol would result in misdiagnosing cases of stage IA carcinoma as a low malignant potential tumor, the overall prognosis of patients with low malignant potential tumors would not markedly change. The prognosis of a patient with a low malignant potential tumor using limited sectioning was within the prognostic range owing to interobserver variability alone. CONCLUSIONS: We conclude that extensive sectioning of ovarian mucinous tumors has limited benefit. PMID- 9372749 TI - Use of perfusion fixation for improved neuropathologic examination. AB - OBJECTIVE: To assess the efficacy of 10% formalin perfusion fixation as a method of rapid fixation to examine the human brain immediately following autopsy. DESIGN: Compare the histology and immunohistochemistry from human brains in which one hemisphere undergoes perfusion fixation using 10% buffered formalin, and the contralateral nonperfused hemisphere undergoes standard 14-day immersion fixation in 8 L of 10% buffered formalin. SETTING: Autopsy material in a general medical surgical university hospital. PARTICIPANTS: Pathologists, neuropathologists, resident pathologists, and pathology assistants. INTERVENTION: Immediately following brain removal, a single hemisphere was perfused with 1 L 10% buffered formalin over a 15- to 20-minute period. The contralateral nonperfused hemisphere served as a control, undergoing standard immersion fixation for 2 weeks in 10% formalin. The perfusion-fixation hemisphere was immediately available for neuropathologic examination, and histologic sections of the brain were processed immediately with the other necropsy tissue sections. This allows completion of a final autopsy neuropathology report within 3 to 5 days in concert with the systemic section of the report. MAIN OUTCOME MEASURE: Perfusion-fixation brain sections were compared with immersion-fixation brain sections from the same brain. The effects on hematoxylin-eosin, Bielschowsky's silver, and immunohistochemical staining were evaluated by an experienced neuropathologist and a general pathologist with no prior knowledge of the fixation technique. RESULTS: Perfusion fixation revealed equal and occasionally superior histologic sections compared with traditional immersion fixation in terms of (1) technical preparation of section, (2) quality and intensity of staining with both hematoxylin-eosin and silver, and (3) immunoreactivity localization with a variety of immunohistochemical reactions. CONCLUSIONS: Immediate perfusion of the brain is an easily performed fixation technique that yields comparable or superior fixation to prolonged immersion fixation and allows an immediate complete neuropathologic examination and report within 3 to 5 days of performance of the autopsy. PMID- 9372750 TI - Rosenthal fibers and eosinophilic granular bodies in a classic acoustic schwannoma. AB - We describe unique features seen in a case of classic acoustic schwannoma. In the central portion of the tumor, abundant Rosenthal fibers and occasional eosinophilic granular bodies were present. Rosenthal fibers are homogeneous eosinophilic structures commonly seen in central nervous system lesions, such as pilocytic astrocytoma, or in the gliotic tissues adjacent to slowly growing neoplasms and some congenital malformations. Eosinophilic granular bodies are also structural markers of slow-growing, well-differentiated neuroglial neoplasms, such as pleomorphic xanthoastrocytoma, ganglion cell tumors, and pilocytic astrocytoma. To the best of our knowledge, however, these two structures have never before been described in schwannomas. PMID- 9372751 TI - Adult-onset nemaline myopathy: a case report and review of the literature. AB - Nemaline (rod) myopathy is a congenital muscle disease with a wide spectrum of phenotypes, ranging from forms with neonatal onset and fatal outcome to asymptomatic forms. An adult-onset variant is characterized by large numbers of rod-containing myofibers, numerous rods per affected myofiber, and the absence of specific structural abnormalities typical of other muscle diseases. Few cases fulfilling these criteria have been described in the literature. Rare cases have had an associated inflammatory component, and the majority of these have occurred in patients with an underlying immunologic disorder. We present an unusual case of an immunologically competent 65-year-old man with late-onset nemaline myopathy, who was previously diagnosed with an inflammatory myopathy based on a muscle biopsy that contained chronic inflammation. His symptoms consisted of a 2 year history of progressive proximal muscle weakness; his family history was unremarkable. A neurologic examination confirmed the presence of bilateral proximal muscle weakness, normal sensation, and decreased upper and lower extremity reflexes. Creatine kinase levels were normal, and electromyographic findings indicated a myopathic process. A modified trichrome stain of the right biceps muscle revealed granular, basophilic, centrally located rods in the atrophic myofibers. Ultrastructurally, these myofibers contained osmiophilic rectangular structures with a latticelike appearance typical of nemaline myopathy. This case illustrates that adult-onset nemaline myopathy, although rare, should be considered in the differential diagnosis of an inflammatory myopathy. PMID- 9372752 TI - The College of American Pathologists, 1946-1996: anatomic and consultative pathology practice. PMID- 9372753 TI - The true neck of the femur: its structure and pathology. 1875. PMID- 9372754 TI - The Otto Aufranc Award. Lovastatin prevents steroid induced adipogenesis and osteonecrosis. AB - Osteonecrosis of the femoral head was induced experimentally in chickens after the administration of a high dose of corticosteroids. Lovastatin was used to prevent the effects of the steroid on adipogenesis in cultured cells, and adipogenesis and osteonecrosis in chickens. The in vitro study, with marrow cells in culture, showed that Lovastatin inhibited steroid induced fat specific gene expression and counteracted the inhibitory effects of steroids on osteoblastic gene expression. For the in vivo study, 83 adult chickens were used: 48 received methylprednisolone 3 mg/kg weekly via intramuscular injection (Group A). Fifteen received the steroid (as in Group A) plus Lovastatin 20 mg per animal per day orally (Group B). Ten chickens received Lovastatin only (Group C). Another 10 received no medication and served as the control group (Group D). Evidence of osteonecrosis was observed in specimens from Group A, including subchondral bone death and resorption, fat cell proliferation, and new bone formation. Conversely, sections from Group B showed less adipogenesis and no bone death. It is concluded that the bipedal chicken is a useful animal model for studies of osteonecrosis and that lipid clearing agents, such as Lovastatin, may be helpful in preventing the development of steroid induced osteonecrosis. PMID- 9372755 TI - The Frank Stinchfield Award. Contribution of cable debris generation to accelerated polyethylene wear. AB - The decision of the senior author of a large total hip replacement practice to switch from wire to braided cable for reattachment of the greater trochanter provided the opportunity to evaluate the long term effects (on acetabular component wear, osteolysis, and component loosening) caused by the introduction of metallic debris (generated by cable fretting and breakage) into the total hip arthroplasty construct. Seven hundred and nine consecutive primary total hip arthroplasties were performed during a 5-year period and followed up for a minimum of 10 years. Wire and cable reattachment of the greater trochanter was used sequentially. At minimum 10-year followup the cable group had significantly more wear, osteolysis, and acetabular radiographic evidence of loosening. Those involved in the design and use of total hip arthroplasty devices must minimize potential sources of metallic debris and other potential sources for third body wear in the total hip arthroplasty construct to help ensure longevity of the arthroplasty. PMID- 9372756 TI - The John Charnley Award. Inhibition of wear debris mediated osteolysis in a canine total hip arthroplasty model. AB - In this study the efficacy of an oral bisphosphonate therapy to inhibit wear debris mediated bone resorption was evaluated in a canine total hip replacement model. Adult canines were randomized to three groups (n = 8 each) with a right uncemented total hip replacement performed on each animal. Group I (control) received no particulate debris. In Groups II and III, a mixture of 1 x 10(9) particles were introduced into the proximal femoral gap intraoperatively. The particle mixture consisted of fabricated ultra high molecular weight polyethylene (mean 2.3 microns, 90% by number), titanium alloy (mean 3.1 microns, 5%), and cobalt chrome alloy (mean 0.8 micron, 5%). Group III canines additionally received oral drug therapy (5 mg once a day, alendronate sodium) which was begun on postoperative Day 7 and continued until the time of sacrifice. Postoperatively, all animals were allowed 24 weeks of full ambulation before euthanasia. Radiographs obtained preoperatively, postoperatively, and at time of sacrifice were evaluated for periprosthetic osteolysis. Interfacial tissues were examined histologically and placed in organ culture and the supernatants were assayed for prostaglandin E2 and interleukin-1. One animal receiving debris (Group II) suffered a periprosthetic fracture and was sacrificed from the study. Radiographically, one of eight Group I (control) and six of seven canines from Group II (debris) had periprosthetic radiolucencies with endosteal scalloping develop. In contrast, only one of eight animals from Group III (debris + alendronate) had periprosthetic radiolucencies develop. Whereas tissues from control animals were mostly fibrous and acellular, tissues from both experimental groups had significant macrophage infiltration. Levels of prostaglandin E2 and interleukin-1 were elevated significantly in periprosthetic tissues from both experimental groups compared with controls. Continuous administration of alendronate effectively inhibited bone lysis for the 24-week duration of the study. This is consistent with the literature indicating that alendronate is incorporated in the mineralizing matrix making it refractory to osteoclastic resorption. This report has significant clinical implications for controlling the most common cause of implant failure. PMID- 9372757 TI - How outcome studies have changed total hip arthroplasty practices in Sweden. AB - The Swedish Hip Registry has defined the epidemiology of total hip replacement in Sweden. Most hip implants are fully cemented. Serious complications and rates of revision associated with total hip replacement have declined significantly despite an increasing number of patients at risk. During the past 5 years only 9% to 10% of hip replacement procedures are revision procedures. Aseptic loosening with or without osteolysis is the major problem and constitutes 73% of the revisions, but the incidence has decreased four times during the past 15 years to less than 3% at 10 years. Even septic complications can be prevented effectively. Demographics are important because male gender and young age increase the risk for revision because of aseptic loosening. Young female patients with rheumatoid arthritis and male patients with a previous hip fracture have five times higher revision rates than elderly patients. The quality of the surgical technique is the most important factor for reducing the risk for revision because of aseptic loosening, but choice of implant is also important. The variations among hospitals in type of surgical technique used is big enough to cause a 100% difference in revision rate for aseptic loosening. Total hip replacement practice in Sweden has improved based on information from this Registry about individualized patient risks, implant safety, and the efficacy of improving surgical and cementing techniques. PMID- 9372758 TI - Maintaining a hip registry for 25 years. Mayo Clinic experience. AB - A computerized database was established for all total joint replacements done at the authors' institution. To date the registry contains information on more than 56,000 arthroplasties of which more than 30,000 involve the hip. The registry was designed to determine the effectiveness of total hip arthroplasty as a function of implant design, surgical technique, and patient selection. Furthermore, by maintaining and updating the patient record, data regarding success or anticipated failure could be communicated to the patient. Finally, this resource would provide reliable information that could be communicated to the orthopedic community. Patients are routinely evaluated at 1, 2, and 5 years postoperatively and at 5-year intervals thereafter by examination or letter or telephone questionnaire. Followup of patients at each interval is approximately 95%. Patients are more likely to respond by questionnaire (rather than be seen in person) if they are older, if a longer time has elapsed since surgery, or if they live a long distance from the clinic. Data are collected by five full time employees including computer and statistical support specifically assigned to the project. The annual joint registry budget is in excess of $400,000. Unfortunately, the future of this endeavor is challenged by the needs to: (1) show cost effectiveness of the activity; (2) update and validate outcomes instruments used as input into the database; and (3) maintain satisfactory followup rates in a medical economic environment that often discourages patient return visits or local assessment. PMID- 9372759 TI - The value of maintaining outcomes in an individual practice for 25 years. AB - Decision making in orthopaedic surgery is facilitated by outcome data, not only from the literature, but also from one's own practice. Between 1971 and 1996, 2602 primary and 587 revision total hip replacements were performed. All had prospective collection of data, which altered surgical practice. A posterior approach in 147 primary total hip replacements resulted in 10 dislocations (6.8%) leading to the use of the anterolateral approach in 1788 subsequent hips with only eight dislocations (0.45%). The initial 298 hips were done in a standard operating room with restricted access and were covered with perioperative antibiotics. No infections occurred permitting ongoing use of inexpensive infection prevention. From 1971 to 1975, 168 classic polished Charnley stems were implanted with only seven stems requiring revision to date. In contrast, use of the matte finished Muller prosthesis in the early 1970s in 58 hips has resulted in nine revised stems. From 1980 to 1990, 789 second generation design matte finished Iowa stems were implanted. Prospective data collected disclosed that a small number (1.5%) of early loosenings occurred and all were associated with extensive bone lysis which made revision difficult. Only polished stems are now cemented by the author. The author firmly believes that his practice patterns have been promptly and appropriately altered by the availability of a prospectively collected hip data file. PMID- 9372760 TI - Overview: maintaining outcomes for total hip arthroplasty. The past, present, and future. AB - Developing and maintaining outcomes for total hip arthroplasty, resulting in meaningful and usable data, presents many challenges for today's clinician. Outcomes data collected must show patients' clinical, functional, and overall quality of life status. Data also must be appropriate to illustrate efficiency, effectiveness, and value of medical interventions provided to payers. Previous and current measures of assessing outcomes of total hip arthroplasty are presented, evaluated, and discussed. Recommended standards for the future, including the identification of specific data needed such as demographics, Short Form-36, patient satisfaction, length of stay, infection rate, return to surgery, and revision rates are introduced, leading to an outcomes based suggested standard of care for total hip arthroplasty with application to patients, providers, and payers. PMID- 9372761 TI - Relationship of total hip arthroplasty outcomes to other orthopaedic procedures. AB - The Medical Outcomes Study Short Form-36 was used preoperatively and 2 years postoperatively to compare patients' self reported assessment of health and function between 151 patients who had primary total hip replacement and 49 patients who had total hip revision, 149 patients who had primary total knee replacements, 41 patients who had lumbar laminectomy, and 43 patients who had scoliosis surgery. Primary total hip arthroplasty and lumbar laminectomy posted equivalent followup scores. Primary total hip arthroplasty showed significant improvements in physical function and health perception when compared with revision total hip arthroplasty; all other health parameters were similar. Primary total hip arthroplasty showed significantly better followup scores and greater improvement in scores in four of nine categories of the SF-36 when compared with primary total knee arthroplasty (despite identical scores preoperatively). Despite a higher level of assessed health preoperatively, patients who had scoliosis surgery compared least favorably with patients who had primary total hip arthroplasty at 2 years followup. In terms of patient self assessment of health and function, primary total hip arthroplasty and lumbar laminectomy for radiculopathy gave the best results. PMID- 9372762 TI - Radiostereometry of hip prostheses. Review of methodology and clinical results. AB - Radiostereometric analysis is a science that enables reliable measurements to be made from radiographs. The method involves several steps including insertion of spheric tantalum markers, radiographic examinations, measurements of radiographic films, and calculations of three-dimensional movements. The precision of the method corresponding to the 99% significance interval varies between 0.15 and 0.6 mm and 0.3 degree and 2 degrees when applied to total hip replacement depending on the technique used. Measurements of implant micromovement during 1 to 2 years after surgery have proved to be of value to predict later clinical failure because of aseptic loosening and revision. Subsidence of the femoral stem or proximal migration of the acetabular cup between 1 and 2 mm has indicated increased risk of early or intermediate term revisions in those prosthetic designs studied so far. Minimum early migration has been recorded for clinically well documented nonpolished stems and polyethylene cups, which probably is one explanation for their long term success. This small amount of early micromotion also has been found in porous coated and screw fixated press fit cups and all hydroxyapatite coated designs hitherto studied. As a first step in a clinical evaluation of new implants or surgical techniques, the predictive value of radiostereometric analysis measurements can be used to reduce the number of patients exposed to the potential risk of clinical failure. PMID- 9372763 TI - Finite element analysis of acetabular wear. Validation, and backing and fixation effects. AB - A two-phase investigation was undertaken to study computational performance aspects of a recently developed finite element formulation that has shown promise in the study of design related influences on total hip arthroplasty wear. In the first phase, computational model predictions were evaluated against directly corresponding physical wear measurements performed in a biaxial rocking hip simulator. The discrepancy between the predictions and the measurements was approximately 4.1%. In the second phase, a bony support bed was introduced to supersede the model's previous simplifying assumption of rigid support at the cup backing. Other factors being equal, computed wear rates differed negligibly for three very different cup backing and fixation modalities studied with the new bony bed support condition, and for two individual cups studied with bony bed support versus the rigid backing support simplification. PMID- 9372764 TI - Options for primary femoral fixation in total hip arthroplasty. Cemented stems for all. AB - In considering the subject of choices for the planning of femoral fixation in total hip arthroplasty, the strength behind the argument that cementing should be preferred in all ages and all conditions comes from three major positions, all supported by excellent data. First, the long term data (15-20 years) for well performed cemented stems are excellent and unmatched. Second, with good cementing techniques, the long term results in patients younger than 50 years of age are equal to the results in patients older than 50 years of age. No longer is there validity to the prior arguments that cementing does not work well in younger patients or that younger patients should have cementless femoral stems. Third, improvements in cementing technique have been shown in nationwide studies to produce statistically significantly better results than the original techniques. PMID- 9372765 TI - Hydroxyapatite coated implants. Total hip arthroplasty in the young patient and patients with avascular necrosis. AB - Two high risk groups for total hip arthroplasty, 136 patients (155 hips) younger than 50 years of age (average age, 38 years) and 44 patients (53 hips) with the diagnosis of avascular necrosis, have a minimum followup of 5 years and a mean followup of 6.8 years. The average Harris Hip Score at last followup totaled 93 and 90, respectively, and thigh pain was reported in 1.3% and 3.8%, respectively. All patients in both groups received the same hydroxyapatite coated femoral stem and the mechanical failure was 0%. No stem was revised for aseptic loosening, 100% of stems were bony stable by radiographic criteria, new bone formation was progressive about the femoral stem, and 0% endosteal lysis was found. The acetabular components had a mechanical failure rate of 10% and 7.5%, respectively, without osteolysis, and an additional 7% and 7.5% failure as a direct result of progressive osteolysis. The results with the porous press fit and hydroxyapatite threaded sockets were far superior to that of the smooth hydroxyapatite press fit sockets and socket failure was associated with thin polyethylene liners and the use of 32-mm head diameters. These findings show a high success rate with a nonporous hydroxyapatite coated titanium femoral stem. However, hydroxyapatite on a smooth acetabular component yielded less predictable results indicating that for long term fixation of the acetabulum an interlock of bone is preferred. PMID- 9372766 TI - Proximally coated ingrowth prostheses. A review. AB - Proximally coated femoral components for cementless total hip replacement were conceived in the early 1980s in response to the proximal stress shielding that was seen with extensively coated devices. The main purpose of this study was to analyze whether these prostheses remain viable options based on the results of presently used devices, while detailing the problems encountered with first generation devices. The evolution of these designs and how they were modified in response to early problems, was reviewed. Initial iterations were less successful because they were sometimes not stable, had problems with thigh pain, and progressive osteolysis. However, second generation devices with greater than 5 years clinical experience seem promising and have shown very low aseptic loosening rates (1%-3%), and less thigh pain (under 5% in most studies). The reader still must await longer term studies to know whether progressive osteolysis will be a problem. These encouraging midterm results can be attributed to improved geometry, instruments, and technique which ensure initial implant stability. Proximal coating must be circumferential, to seal the diaphysis from were debris. After incorporating design changes in response to the significant failures of early devices, the concept of proximal coating for cementless femoral stems seem viable, as long as the twin requirements of circumferential coating and rigid initial stability are realized. PMID- 9372767 TI - Treatment of complications in primary cementless total hip arthroplasty. AB - Five hundred eight consecutive cases (481 patients) treated with the extensively porous coated Anatomic Medullary Locking prosthesis were followed for an average of 9 years (range, 5-14 years). Thirty-one (6%) hips were lost to followup and 33 (7%) hips had complications that required revision surgery. The indications for revision were symptomatic stem loosening (six cases), symptomatic cup loosening (five cases), asymptomatic periarticular osteolysis (seven cases); trochanteric fracture through an osteolytic cyst (four cases), polyethylene fracture (five cases), sepsis (one case), and heterotopic ossification (one case). The surgical treatment of these complications is described. After these revisions, 11 (33%) cases had additional complications, most commonly a dislocation. Four required a second revision. Questionnaires and physical examinations were used to compare the outcome of the cases requiring revision with the outcome of those that did not. There were no differences in patient satisfaction between cases requiring revision surgery and those that did not (97% and 95% patient satisfaction, respectively). Function was also similar between the two groups, with 93% reporting increased function in each group. PMID- 9372769 TI - Tapered design for the cementless total hip arthroplasty femoral component. AB - The long-term behavior of total hip arthroplasty ultimately is determined by adaptive bone remodeling. Stress adaptation creating various degrees of metaphyseal bone atrophy has occurred with prostheses designed for tight distal fit and fill. This phenomenon has been explained as bone adaptation resolving the conflict between femoral component stiffness and bone flexibility. However, clinical observations indicate that a different premise may be operational when prostheses with tapered geometries are used. The results of four published reports (748 arthroplasties) using cementless femoral components of a tapered design were reviewed. The review found a low incidence of aseptic loosening (0.5%) and significant thigh pain (0.5%), and a radiographic incidence of proximal bone atrophy of 6%. In no case was the metaphyseal bone atrophy described as severe or extensive. These findings challenge the premise that reactive bone adaptation is related to the issues of femoral component stiffness exclusively and propose that femoral component geometry may have an influence on bone adaptation. PMID- 9372770 TI - Difficult complications after hip joint replacement. Dislocation. AB - Dislocation after hip replacement occurs at an overall incidence of 2% to 3% and has significant cost and morbidity implications. Statistically increased incidence is observed in females and in the elderly, and after reoperation procedures. Specific causes include cup malrotation, trochanteric migration, and decreased femoral offset. Head size, leg length, and postoperative mobilization have not proven to be causative factors, but the posterior exposure statistically and consistently is associated with increased instability. Extended acetabular walls do lessen the incidence of dislocation in the primary but even more significantly in the revision procedure. Early (< 3 months) dislocations successfully are treated by 4 to 8 weeks of immobilization in 60% to 70% of instances. The most successful reoperations are those in which the specific cause of the dislocation has been defined. The success rate is approximately 80% for cup reorientation and trochanteric advancement. Nonspecific or ill defined causes are managed successfully by surgical intervention in only approximately 50% of cases. With extensive soft tissue compromise, limited experience with certain salvage options include the bipolar implant with a reported success rate of approximately 80%. Captive articular designs also seem to be successful in approximately 70% of instances but with relatively short term followup and lingering concerns regarding the long term integrity of the fixation. PMID- 9372768 TI - Custom and modular components in primary total hip replacement. AB - Cementless custom implants attempted to enhance fit and fill of variable hip geometry. Fabrication of custom implants in referenced from a computed tomography scan, thus allowing three dimensional specifications of femoral anatomy. However, the aggregate charge of manufacturing the implant and obtaining the computed tomography scan is prohibitive in today's healthcare climate. Clinical studies have not shown that customized implants incrementally improve clinical success or implant longevity. Modular prostheses allow the surgeon intraoperative versatility, allowing adjustment of leg length, offset, neck length, anteversion, and fixation. This is particularly helpful in developmental dysplasia of the hip and posttraumatic arthritis. Other advantages of modularity include decreased implant inventory and the ability to remove the femoral head at revision surgery to improve exposure or change head size without component removal. Subsequent clinical experience has witnessed significant drawbacks associated with modularity. These include corrosion, especially with mixed metals, fretting, dissociation, implant fracture below the head and neck taper joint, and reduced range of motion. In addition, thin acetabular polyethylene contributes to higher were rates, earlier failure, local or distal debris particles, and osteolysis. Finally, the cost of modular implants is generally higher than a comparable monolithic prosthesis. In primary hip arthroplasty, use of custom or modular implants should be judicious. Modularity beyond the head and neck junction should be reserved for those cases where a comparable monolithic implant would not suffice. PMID- 9372771 TI - Update on nerve palsy associated with total hip replacement. AB - Nerve palsy is an uncommon but acknowledged complication of total hip replacement. The overall prevalence is approximately 1%. The sciatic nerve, or the peroneal division of the sciatic nerve, is involved in nearly 80% of cases. The risk of nerve palsy in association with total hip replacement is increased for female compared with male patients, with a diagnosis of developmental dysplasia, and with patients undergoing revision surgery. In the majority of cases, the origin of the palsy is unknown. Because peripheral nerves are sensitive to compression, unrecognized compression may play a role in these cases. The prognosis for neurologic recovery is related to the degree of nerve damage. Complete, or essentially complete, recovery occurs in approximately 41% and another 44% have only a mild deficit. Approximately 15% have a poor outcome characterized by weakness that limits ambulation and/or persistent dysesthesia. Patients with some motor function immediately after the operation and those who recover some motor function within approximately 2 weeks of surgery have a good prognosis for recovery. In general, recovery of femoral nerve palsies is more predictable than that of sciatic palsies. PMID- 9372772 TI - Fixation of the acetabular component. The case for cement. AB - The long-term success rate of cemented sockets in total hip arthroplasty has been well documented in patients who are 60 years of age and older and who have had a followup of as many as 16 years. The failures with cemented sockets have been observed in young patients, patients with poor bone stock (rheumatoid and dysplastic hips) with metal backed components, and in revision surgery with loss of acetabular bone. Ranawat et al have shown that most mechanical failures of cemented socket fixation within 10 years of primary operation is attributable to failure to achieve a good fixation initially of the cement and bone. Volumetric wear of the polyethylene of a cemented socket against a 22- or 28-mm femoral head is compared with the metal backed cemented and noncemented cups. The increase in volumetric polyethylene particles with metal backed cemented sockets and noncemented sockets will induce histiocytic response. The mechanism of histiocytic invasion should be similar for cemented all polyethylene sockets and noncemented sockets. It manifests itself in the cemented socket as global radiolucency when the socket is loose and as osteolysis when it is well fixed for noncemented and cemented sockets. If the number of particles coming out in a noncemented and hybrid total hip replacement are greater, osteolysis would be expected to increase with longer followup. The technique of cemented polyethylene sockets requires organization of the surgical team and hypotensive epidural anesthesia. Under these conditions the procedure is very reproducible. As far as cost is concerned, the all polyethylene socket is significantly less expensive. It seems that cemented total hip replacement is most suitable and perhaps is the right kind of operation for treating osteoarthritis of the hip for patients who are 60 years of age and older because the procedure is reproducible, the quality of arthroplasty is excellent, and it is durable, lasting as many as 15 years in 90% to 95% of the cases. PMID- 9372773 TI - Primary cementless acetabular reconstruction in patients younger than 50 years old. 7- to 11-year results. AB - The efficacy of primary cementless acetabular reconstruction in patients younger than 50 years of age was analyzed in 79 consecutive cementless, hemispheric, porous coated acetabular reconstructions (Harris-Galante-I). The average age was 37 years at surgery (range, 20-49 years). The average followup was 106 months (range, 78-126 months). No acetabular reconstructions were revised for aseptic loosening. Two stable acetabular reconstructions were revised during femoral revision. Two excessively worn polyethylene liners were exchanged and one acetabular osteolytic area was debrided and grafted; these procedures retained the metal shell. At final followup, all 72 acetabular reconstructions were radiographically stable. Acetabular osteolysis occurred in five cases (7.4%), from 84 to 104 months. Acetabular or femoral osteolysis occurred in patients with increased polyethylene wear. Polyethylene wear was inversely related to the patient's age. Using revision and loosening, the Kaplan-Meier 10 year survival of the acetabular reconstruction was 98.8% (95% confidence interval, 96.6%-100.%). The intermediate results of cementless, hemispheric, porous coated acetabular reconstruction in younger patients was excellent with no radiographic loosening. At 7- to 11-year followup, osteolysis was the most common problem and increased in frequency and extent with continued in vivo duration. PMID- 9372774 TI - Natural history and treatment outcomes of childhood hip disorders. AB - Normal hip joint growth and development occur as a result of a genetically determined balance of growth of the acetabular and triradiate cartilages and the presence of a well located centered spheric femoral head. The majority of acetabular development is determined by age 8 years. This is a watershed age for prognosis in many pediatric hip disorders. Hip joint growth and development and how these are affected by the disease process and treatment interventions profoundly affect outcome. Outcomes of these disease processes (congenital hip dislocation and dysplasia, Legg-Calve-Perthes disease and slipped capital femoral epiphysis), is multifactorial but profoundly influenced by the age at the disease onset (birth to the adolescent growth spurt), and the effects of treatment on the relationship between femoral head and acetabular development. The natural history of many of these childhood hip disorders is the development of degenerative joint disease. Degenerative joint disease and clinical disability may develop in these conditions despite standard up to date treatment interventions. In most of the hip diseases discussed, patients usually do well clinically for many years regardless of treatment. PMID- 9372775 TI - Free vascularized fibula grafting for the treatment of osteonecrosis of the femoral head. AB - Sixty-five patients (88 hips) who received free vascularized fibula grafting for treatment of osteonecrosis of the femoral head at the University of Pittsburgh Medical Center, were followed for at least 3 years (average followup, 5.5 years; range, 3-7 years). There were 46 men and 19 women with an average age of 37 years (range, 20-52 years). All patients were evaluated using history, physical examination, Harris Hip Score, anteroposterior and lateral radiographs, and magnetic resonance images. The classification system of Steinberg et al (1995) was used to stage the disease. At final evaluation, 31 hips (35.2%) were rated excellent (Harris Hip Score > 90 points, minimal or no pain), 30 hips (34.1%) were rated good (Harris Hip Score 80-89 points, slight pain), seven hips (8%) were rated fair (Harris Hip Score 70-79, slight or moderate pain), and 20 hips (22.7%) were rated poor (Harris Hip Score < 70, pain). Twenty hips in 17 patients required total hip arthroplasty. In the remaining hips, the disease apparently arrested and the contour of the femoral head was preserved. Kaplan-Meier survivorship analyses showed that the probability of conversion to total hip arthroplasty within an average of 5.5 years after free vascularized fibula grafting was 28% for Stage II hips and 38% for Stages III and IV hips. The hip survival rate for subgroups at 5.5 years was 100% for Stages IC and IIA, 94% for Stage IIB, 50% for Stage IIC, 80% for Stage IIIB, 58% for Stage IIIC, 72% for Stage IVA, and 58% for Stage IVB. Free vascularized fibula grafting is a reliable operation and can preserve hip function and diminish pain successfully. PMID- 9372776 TI - Total hip arthroplasty in the young adult. AB - The durability of cemented and hybrid total hip arthroplasty in the young adult was evaluated. A consecutive series of primary cemented total hip arthroplasties performed between 1970 and 1976, and a consecutive series of primary hybrid total hip arthroplasties performed between 1986 and 1991, were evaluated for revision and radiographic loosening of the components. All patients were younger than 50 years of age at the time of surgery and all surgery was performed by one surgeon. At minimum 20 years followup of the cemented group (93 hips in 69 patients) 22% of hips (21 hips) were revised for aseptic loosening (5% of femoral components, five hips, and 19% of acetabular components, 18 hips). At 5- to 10-year followup of the hybrid group (45 hips in 37 patients) 18% of hips (eight hips) were revised for aseptic loosening (18% of femoral components, eight hips, and 0% of acetabular components, 0 hips). Although the cemented femoral component used in the hybrid series showed a marked increase in revision and loosening compared with the cemented series, the excellent fixation obtained with uncemented acetabular components has encouraged the authors to continue the use of hybrid fixation in the young adult. However, the femoral component has been modified to incorporate a polished surface finish and a stem geometry similar to the Charnley flat back prosthesis used in the cemented series. PMID- 9372777 TI - Extensively coated femoral components in young patients. AB - A review of 174 hips in 154 patients younger than 50 years of age who underwent primary total hip arthroplasty with a cementless acetabular component and an extensively coated femoral component done by one surgeon was performed to determine whether this method of fixation improves the results of previously reported comparable series using different methods of fixation. The average age was 37.6 years. The average followup was 8.3 years (range, 2-13 years). Eighty eight hips had at least 10 years followup. Sixteen (9%) hips had severe stress shielding. There were 13 (7.5%) acetabular failures. Of 144 porous coated cups, three were revised for wear and one for dislocation. Another was revised 11 years postoperatively for late loosening secondary to catastrophic acetabular lysis. Excluding the bipolar and threaded components (30 hips), five (3.4%) porous coated cups were revised for failure. Of the 174 fully coated stems, 99.4% had stable fixation, 167 (96%) were ingrown, six (3.4%) had stable fibrous fixation, and one (0.6%) was unstable. Two (1.1%) femoral stems were revised. The total rate of osteolysis was 4%. Cementless extensively porous coated stems and porous coated acetabuli give excellent lasting results in young patients. PMID- 9372778 TI - Prediction of rotator cuff repair results by magnetic resonance imaging. AB - Thirty chronic rotator cuff tears were repaired consecutively and evaluated prospectively using a precise anatomic description of the tear that included the rotator interval, the Constant functional score, and an assessment of the tendon state and the atrophy of the supraspinatus muscle by preoperative and postoperative magnetic resonance imaging. Early correlations (mean followup, 21.1 months) attempted to define predictive factors of the final outcome of the repair, physical factors indicative of final tendon state, and postoperative evolution of supraspinatus atrophy. Magnetic resonance imaging oblique sagittal views showed that supraspinatus atrophy correlated with the sagittal and coronal extent of the tear and represented a strong predictive factor of postoperative retearing. At followup, 15 (50%) cuffs were continuous and thick, seven (23%) were continuous but thin, and six (20%) were retorn. Two (7%) cuffs had been repaired only partly. In the group with a persistent tear, flexion strength and differential Constant score were correlated with the final tendon state with no excellent or good results, and with less than 4 kg of strength. Supraspinatus atrophy improved in 18 of the 22 postoperative continuous cuffs, but never decreased in persistent tears, although there was pain relief and functional gain. PMID- 9372779 TI - Distal realignment of the patellar tendon to correct abnormal patellar tracking. AB - Between January 1980 and January 1994, 31 knees required distal realignment of the extensor mechanism to treat lateral patellar subluxation that could not be corrected with lateral patellar release and vastus medialis advancement during total knee arthroplasty. Fifteen had a preoperative valgus angle of more than 12 degrees, and 16 were undergoing revision total knee arthroplasty. Ten knees had a modified Roux-Goldthwait procedure, 18 had medial tibial tubercle transfer, and three had medial transfer of the medial 1/2 of the patellar tendon. The length of followup ranged from 2 to 16 years. No late patellar subluxations or dislocations have occurred in any of these cases. Three cases of medial tibial tubercle transfer had hematomas develop, with two requiring surgical evacuation; one of these developed a late infection. No fractures or displacements of the tubercle fragment have occurred. No significant patellar complications have occurred in those patients who underwent the modified Roux-Goldthwait procedure or the medial transfer of the medial 1/2 of the patellar tendon. One year after surgery, the mean knee flexion was 113 degrees, four knees had a flexion contracture of 5 degrees, and none had a quadriceps lag. PMID- 9372780 TI - Joint loading with valgus bracing in patients with varus gonarthrosis. AB - The purpose of this study was to determine whether a brace designed to unload varus degenerative knees actually alters medial compartment loads by decreasing the adduction moment. Eleven patients who had arthrosis confined to the medial compartment were fitted with a valgus brace and tested before and after brace wear with pain and function scoring instruments and by automated gait analysis. The biomechanical data from these patients were compared with those from 11 healthy control subjects. Scores from an analog pain scale decreased 48% with brace wear, and function with activities of daily living increased 79%. Mean adduction moment without the brace measured 4.0 +/- 0.8% body weight times height versus 3.6 +/- 0.8% body weight times height when wearing the brace (10% decrease). The mean adduction moment for control subjects was 3.5 +/- 0.6% body weight times height. Thus, the mean adduction moment decreased from approximately one standard deviation from the normal mean to a value that is similar to the control value. Nine of 11 patients had a decrease in the adduction moment with the brace, five of 11 patients had a reduction higher than 10%, and decreases in this moment were as high as 32%. This study shows that pain, function, and biomechanical knee loading can be altered by a brace designed to unload the medial compartment of the knee. PMID- 9372781 TI - Lengthening of the lower limbs in patients with achondroplasia and hypochondroplasia. AB - Ten years of experience in lower limb lengthening achieved in 35 patients with achondroplasia and seven patients with hypochondroplasia is reported. A uniform method of callus distraction (callotasis) was used in all cases, although the order of lengthening of each bone differed among the cases. The mean age of the patients at the time of first operation was 14.5 years; at followup, the mean age was 18.8 years. The mean lengthening achieved in the femur was 7.2 cm (range, 4.5 12 cm) and in the tibia 7.1 cm (range, 4.5-13 cm). More lengthening was achieved in the more recent cases. The function of lengthened limbs, evaluated by physical strength tests, was better at followup than before lengthening in the growing children, although the mechanical axes of the lengthened bones were not necessarily in correct alignment. PMID- 9372782 TI - Effect of plantar fasciotomy on stability of arch of foot. AB - Five anatomic specimen feet were studied at three different loading levels to determine the three-dimensional position of the individual bones constituting the arch. Bone displacements were compared before and after plantar fasciotomy. Bone displacements changed to a greater extent with higher loads. With a 222-N load the greatest difference in position in dorsiflexion after fasciotomy occurred at the talar to tibial joint, followed by the metatarsal relative to navicular and navicular to talar joints. The greatest difference in displacement in eversion was at the metatarsal relative to navicular, followed by the navicular to talar and calcaneal to talar joints. The greatest difference in displacement in abduction was at the navicular to talar and then the calcaneal to talar joints. The observed displacement of all joints, with changes about all three axes, was consistent with the finding of flattening of the arch in previous reports on plantar fasciotomy. Thus, these data suggest that sectioning of the fascia, which sometimes is performed for fasciitis, may have an effect on the mechanical behavior of the arch. PMID- 9372784 TI - Dysbaric osteonecrosis in divers and caisson workers. An animal model. AB - Dysbaric osteonecrosis was induced successfully in adult sheep after 12 to 13, 24 hour exposures to compressed air (2.6-2.9 atmospheres absolute) during a 2-month period. All exposed sheep had decompression sickness and extensive bone and marrow necrosis in their long bones. Radiographic analysis of these progressive lesions showed mottled to distinct medullary opacities and endosteal thickening characteristic of dysbaric osteonecrosis. Six months after the last hyperbaric exposure, neovascularization of once ischemic fatty marrow was centripetal from the diaphyseal cortex. Proliferating endosteal new bone, fatty marrow calcification, and appositional new bone formation were widespread. Juxtaarticular osteonecrosis involved marrow fibrosis and loss of osteocytes in subchondral cortical bone. Tidemark reduplication in juxtaarticular bone and cartilage thinning suggested possible early osteoarthritis induction by recurrent episodes of transient ischemia after multiple hyperbaric exposures. Dysbaric osteonecrosis appears to involve a bone compartment syndrome of elevated intramedullary pressure initiated by decompression induced N2 bubble formation in the fatty marrow of the long bones. An animal model that can be used to investigate the pathogenesis, diagnosis, and treatment of dysbaric osteonecrosis is discussed. PMID- 9372783 TI - Predicting failure of thoracic vertebrae with simulated and actual metastatic defects. AB - Indications for operative treatment in spinal metastatic disease depend on estimates of vertebral loadbearing capacity. There are no noninvasive diagnostic tools for estimating vertebral loadbearing capacity in the presence of a metastatic lesion. Thus, relationships between vertebral failure load and measurements from computed tomography data were investigated to determine if measurements that account for defect size and bone density can predict loadbearing capacity better than can defect size alone. Cylindrical defects were created in thoracic vertebrae of 20 anatomic specimen spinal segments, with 10 other segments serving as controls. Five vertebrae with actual metastatic defects also were tested. Vertebrae were scanned using quantitative computed tomography, and the defect size and the axial rigidity of the midvertebral cross section were calculated using an image analysis program. The spinal segments were tested to failure using a combination of axial compression and anterior flexion. Linear regressions between axial rigidity and absolute failure load showed a high positive correlation, but there was no correlation between defect size and failure load. Axial rigidity may prove useful as a noninvasive assessment of vertebral loadbearing capacity in patients with spinal metastatic disease. PMID- 9372785 TI - Sacral mass in a 56-year-old woman. PMID- 9372786 TI - Femoral nailing without a fracture table. PMID- 9372787 TI - Sigurd Ramfjord and Major Ash, Jr.: periodontology and occlusion at Michigan. PMID- 9372788 TI - Cloning and characterization of porcine enamelin mRNAs. AB - Dental enamel forms by matrix-mediated biomineralization. The components of the developing enamel matrix are generally specific for that matrix. The primary structures of three enamel proteins-amelogenin, tuftelin, and sheathlin (ameloblastin/amelin)-have been derived from cDNA sequences. Here we report the cloning and characterization of mRNA encoding a fourth enamel protein: enamelin. The longest porcine enamelin cDNA clone has 3907 nucleotides, exclusive of the poly(A) tail. The primary structure of the secreted protein is 1104 amino acids in length. Without post-translational modifications, the secreted protein has an isotope-averaged molecular mass of 124.3 kDa and an isoelectric point of 6.5. Polymerase chain-reaction phenotyping of enamelin cDNA suggests that porcine enamelin transcripts are not alternatively spliced and use a single polyadenylation/cleavage site. Immunohistochemical and Western blot analyses with an affinity-purified antipeptide antibody specific for the enamelin carboxyl terminus demonstrate that enamelin is synthesized and secreted by secretory-phase ameloblasts. The parent protein is a 186-kDa glycoprotein that concentrates along the secretory face of the ameloblast Tomes' process. Intact enamelin and proteolytic cleavage products containing its carboxyl terminus are limited to the most superficial layer of the developing enamel matrix, while other enamelin cleavage products are observed in deeper enamel. PMID- 9372790 TI - Eugenol activates Ca(2+)-permeable currents in rat dorsal root ganglion cells. AB - Although little is known about the mechanism of action of eugenol, some related compounds have been compared with capsaicin derivatives in terms of the relationship between their chemical structure and activity. To elucidate whether eugenol and capsaicin act via a common mechanism at the neuronal membrane, we investigated the effects of eugenol on rat DRG neurons using the whole-cell patch clamp technique. Eugenol (0.125-1 mmol/L) produced an inward current in a concentration-dependent manner. The reversal potential for this inward current was around 0 mV in PSS. In Na(+)-deficient solutions, the amplitude of the inward current was slightly reduced at negative holding potentials, whereas in Ca(2+) free solution, it was markedly reduced at all holding potentials tested. The reversal potential was not changed by superfusion with either solution. Niflumic acid (100 mumol/L) produced a significant inhibition of the current without a change in the reversal potential. These results suggest that eugenol activates a Ca(2+)-permeable channel as well as a Cl- channel. The latter channel may have been activated by the increase in intracellular Ca2+ concentration caused by the activation of the Ca(2+)-permeable channel. Capsazepine (10 mumol/L) partially inhibited the eugenol-induced current and completely inhibited the capsaicin induced current. Eugenol (1 mmol/L) produced an inward current even after occurrence of desensitization of the capsaicin-induced current had occurred. Our results suggest that eugenol activates a Ca(2+)-permeable ion channel in rat DRG neurons through two different mechanisms: a capsaicin receptor-mediated pathway and a pathway independent of the capsaicin-receptor. PMID- 9372789 TI - Identification, partial characterization, and distribution of versican and link protein in bovine dental pulp. AB - The dynamics of changes in the cellularity and extracellular matrix composition of dental pulp varies considerably during tooth development and maturation. In this paper, we studied matrix proteoglycans where we hypothesized that they played important roles in structural, spatial, and transport aspects of pulpal development and maintenance. The pulpal tissue was collected from partially erupted bovine incisors, pulverized, and then extracted with 6 M guanidine-HCl. The extract was subjected to anion column chromatography (DEAE-8HR), and the fractions collected were screened by dot-blot immunoassay by means of monoclonal antibodies generated against 4- and 6-sulfated chondroitin sulfate isomers, and keratan sulfate, 2-B-6, 3-B-3, and 5-D-4, respectively. The chondroitin-6-sulfate was the major glycosaminoglycan species and occurred as a large-molecular-weight proteoglycan (> 500 kDa). After further purification, it was subjected to agarose/acrylamide composite gel electrophoresis, and it migrated as a single band stained with Stains-All. The band was immunopositive against antibody 3-B-3 by Western blot analysis. The partial amino acid sequence analyses of the core protein clearly indicated this molecule to be versican. The presence of link protein was also confirmed by Western blot analysis with an anti-link protein monoclonal antibody, 8-A-4. Furthermore, immunohistochemical study indicated that the distributions of versican and link protein coincide in the dental pulp and are enriched in the peripheral area of the tissue just beneath the odontoblast layer. Since the dental pulp contains hyaluronan, versican may bind to hyaluronan via its hyaluronan-binding domain, where this association is stabilized by link protein. This complex, then, could form large hydrated proteoglycan aggregates that fill the extracellular space, support odontoblasts, and/or facilitate the transport function of metabolites and nutrients within the tissue. PMID- 9372791 TI - Measurement of velopharyngeal movements induced by isolated stimulation of levator veli palatini and pharyngeal constrictor muscles. AB - The levator veli palatini (LVP) and superior pharyngeal constrictor muscles (PC) close the velopharynx. However, for the velopharyngeal movements to be understood in detail, each muscle contraction must be analyzed precisely. This study was performed to clarify the velopharyngeal movement which was induced by a single muscle contraction, LVP or PC. Using a nasopharyngeal fiberscope, we analyzed the velopharyngeal movement associated with the contraction of the LVP and PC muscles in mongrel dogs. To elicit the maximal contraction of each muscle, we applied repetitive electrical stimulation to each peripheral nerve efferent to the LVP or PC muscle. Stimulation with a frequency of 77 Hz and 83 Hz induced maximal tension in the LVP and PC muscles, respectively, in isometric contraction. In a second series of experiments, fiberscopic views of the velopharyngeal movements associated with each muscle's maximal contraction were recorded. The degree of closure was calculated at several sections. The LVP muscle pulled the caudal fourth of the soft palate, while the PC projected the posterior wall at the level of the caudal end of the soft palate. The PC muscle also projected the lateral wall of the velopharynx. The effect of LVP contraction on the lateral wall was very small. These results show that the velopharyngeal movement associated with LVP contraction is very different from that with PC contraction. PMID- 9372792 TI - Impact velocities of the teeth after a sudden unloading at various initial bite forces, degrees of mouth opening, and distances of travel. AB - A potentially dangerous situation arises when an individual bites on hard and brittle food which suddenly breaks, since the impact velocity of the lower teeth onto the upper teeth after the food is broken can be high and may cause dental damage. The present experiments were designed to study the magnitude of the impact velocity after a sudden unloading at various initial bite forces, degrees of mouth opening, and distances of travel. Subjects were asked to perform a static biting task during which the resistance to the bite was suddenly removed. The upward mandible movement was arrested after a certain distance. The velocity of the lower teeth at impact was calculated just before the mandible came to a standstill in combinations of 4 different bite forces (100, 80, 60, and 40 N), 4 different initial degrees of mouth opening (33.5, 30.5, 27.5, and 24.5 mm), and 3 different distances of travel of the mandible (4.5, 3.0, and 1.5 mm). We found that the bite force rapidly declined after the unloading, resulting in a small impact velocity of the lower front teeth. This impact velocity largely depended on the magnitude of the initial bite force and the distance traveled; it was barely sensitive to variations in degree of initial mouth opening. The maximal velocity of the lower teeth was 0.43 m/s (at an initial bite force of 100 N). This maximum was reached after a distance of travel of about 4 mm in 12 ms. The data suggest that the rapid decline in bite force coupled with a limitation of impact velocity is due to the force-velocity properties of the active jaw muscles and is not caused by neural control. PMID- 9372793 TI - Viscoelastic properties of the pig temporomandibular joint articular soft tissues of the condyle and disc. AB - It has been suggested that a sustained loading condition such as clenching could compress the temporomandibular joint (TMJ) articular soft tissues. However, there is still no clear understanding of how the TM joint articular tissues respond under compression. To answer this question, we performed in vitro indentation tests on fresh articular discs and cartilage-bone systems of the condyles of 10 Yorkshire pigs (aged 7 months) using a self-developed indentation tester. The indenter was 5 mm in diameter and was controlled by means of a computer-aided feedback mechanism. Bilateral condyles from the same mandible were uniformly prepared; one was used for measurements under sustained compression (SC) and the other for measurements under intermittent compression (IC). The displacements of the indenter induced by a SC of 10, 20, and 30 Newtons (N, units of force) for 10 min and by an IC, also of 10, 20, and 30 N, with one-second duration and two second intervals for 10 min were measured by means of a displacement sensor with a resolution of 0.001 mm. From these data, the indentation curves of the articular discs and the cartilage-bone systems were calculated. Both the disc and the articular cartilage showed characteristic displacement vs. time curves namely, an instantaneous deformation upon load application, followed by a time dependent creep phase of asymptotically increasing deformation under constant load. However, the indentation curves of the two tissues were not identical: The deformation of the articular cartilage was dose-dependent, but that of the disc was not. Moreover, the articular cartilage deformed significantly less under IC than under SC. This difference was not found in the disc. It can be concluded that both the disc and the articular cartilage of the pig temporomandibular joint have viscoelastic properties against compression; however, the disc is stiffer than the articular cartilage. PMID- 9372794 TI - Isolation of Enterobacteriaceae from the mouth and potential association with malodor. AB - Bad breath is a common phenomenon, usually the result of bacterial metabolism in the oral cavity. It is generally accepted that Gram-negative bacteria are responsible for this problem, largely through degradation of proteinaceous substances. In initial experiments, screening of malodorous isolates following outgrowth of samples obtained from saliva, periodontal pockets, and the tongue dorsum yielded enterobacterial isolates. Clinical studies were conducted to examine the prevalence of such bacteria in four different populations: orthodontic patients, malodor clinic patients, complete-denture wearers, and a healthy young population. The prevalence of Enterobacteriaceae in the oral cavities of the denture-wearing population was very high (48.0%) as compared with the other groups: 27.1% in the malodor clinic patients, 16.4% in the normal population, and 13% among orthodontic patients. Isolates of Klebsiella and Enterobacter emitted foul odors in vitro which resembled bad breath, with concomitant production of volatile sulfides and cadaverine, both compounds related to bad breath. When incubated on a sterile denture, enterobacterial isolates produced typical denture foul odor. Isolates exhibited cell-surface hydrophobic properties when tested for adhesion to acryl and aggregation with ammonium sulphate. The results, taken together, suggest that Klebsiella and related Enterobacteriaceae may play a role in denture malodor. PMID- 9372795 TI - A three-year clinical trial of a combination of trimetaphosphate and sodium fluoride in silica toothpastes. AB - The relative efficacy of NaF silica toothpastes containing 1000 ppm fluoride and 1500 ppm fluoride in the control of dental caries is not clear-cut. Also, it has not been established that incorporation of trimetaphosphate (TMP) improves the anticaries activity of NaF toothpastes. A three-year clinical trial was conducted to test the hypotheses that: (i) the anticaries activity of NaF toothpastes containing 1500 ppm F was greater than that of NaF toothpastes containing 1000 ppm F, and (ii) inclusion of TMP improved the efficacy of NaF silica pastes. Subsidiary aims included determination of whether frequency of toothbrushing and method of rinsing after brushing were correlated with caries increments. The study involved 4196 children aged 11 to 12 years at outset. These participants had been selected from a pool of 7374 potential subjects on the basis of caries experience and dental eruption pattern. They were stratified by sex, examiner, and presence of calculus and caries, and were allocated at random to one of the four toothpastes under study. Using mirror and probe and also FOTI, we carried out clinical examinations at baseline and annually thereafter for 3 yrs. Bitewing radiographs of a subset of children were taken at baseline and at the end of the study. The outcome measure for the study, DMFS increment, was defined as the increase in caries over 3 yrs, taking into account changes occurring on individual tooth surfaces. Data for 3467 subjects were available for analyses at both baseline and year 3 examinations. Radiographs were taken for 1942 subjects at both baseline and year 3 examinations. The mean three-year clinical-only DMFS increment for the subjects using 1500-ppm-NaF pastes was 3.93, which was 6% lower than the corresponding mean of 4.19 for the 1000-ppm-NaF pastes. There was no significant difference between the mean DMFS increment for those using paste with or without TMP. Subjects who claimed to brush more frequently or who claimed not to use a tumbler to rinse after toothbrushing had lower three-year DFMS increments. PMID- 9372796 TI - A novel system of human submandibular/sublingual saliva collection. AB - The assessment of submandibular/sublingual (sm/sl) saliva is a procedure of increasing significance. However, the collection of these fluids by traditional techniques is difficult and therefore often neglected. To collect sm/sl saliva, we have assembled a novel, universal system consisting of four parts-collecting tubing, a buffering chamber, a storing tube, and a suction device. Submandibular/sublingual saliva samples were collected from ten healthy and ten xerostomic individuals. The system showed intra-examiner reproducibility of 0.92 for healthy and 0.89 for xerostomic subjects, and inter-examiner reproducibility of 0.93 for normal subjects and 0.80 for xerostomic individuals. The flow rates obtained by the present collecting set-up were similar to those measured by all known previous methods that were published during the last 40 years. The system was also efficient, in that more than 90% of the fluid that entered the system was eventually collected in the storing tube for analysis. The system appears to collect relatively pure sm/sl fluids, since contamination of the collected sample by a stimulant solution swabbed repeatedly over the tongue during saliva collection was minimal. The system is reliable, safe, practical, and comfortable for the patient. PMID- 9372797 TI - The influence of the amalgam alloy on the survival of amalgam restorations: a secondary analysis of multiple controlled clinical trials. AB - Data from 14 independent controlled clinical trials on the oral behavior of Classes 1 and 2 amalgam restorations, with a follow-up between five and 15 years, were re-evaluated by secondary analysis for the influence of alloy composition on the survival of amalgam restorations. For the analysis, 3119 restorations were available, which were made from 24 different alloys by a group of seven operators. The alloys were divided into four groups according to their zinc content (zinc-containing and zinc-free) and their copper content (conventional and high-copper). During the follow-up of the trials, the restorations were annually assessed for failures, which were classified as to (1) restoration-, (2) restorative process-, and (3) patient-related reasons. With the restoration related failures, survival functions of the restorations were estimated by alloy and alloy group. The total number of failed restorations was 481, of which 77% were restoration-related and 14% process-related. Eighty percent of the restoration-related failures were due to some form of fracture of the amalgam. Restorations of conventional zinc-free alloys had the shortest survival. After 13 years, only 25% survived. Zinc and a high copper content had an equally favorable influence on the survival rate, which was 70% after 13 years when either was present. The highest survival rates were of restorations of zinc-containing high copper alloys: 85% after 13 years. The zinc and copper contents of the alloy contributed to the corrosion resistance of the amalgams, which in turn influenced the survival of the restoration. The current ISO Standard 1559 on alloys for dental amalgam should be modified to account for these factors that influence the survival of amalgam restorations. PMID- 9372799 TI - An inadequate supply of healthcare leaders. PMID- 9372800 TI - The manager who was hired to fire. PMID- 9372801 TI - Alaska Colleagues in Caring. PMID- 9372798 TI - A new optical 3-D device for the detection of wear. AB - For the clinical performance of new dental restorative materials to be accurately assessed, the three-dimensional anatomical changes of the functional surfaces of the restoration must be elucidated over time. To this end, a highly accurate 3-D optical scanner has been developed that utilizes the principles of triangulation and a reference-free automated 3-D superimposition software. The aim of this study was to assess the accuracy and the precision of the new system with and without referenced positioning. Additionally, the ability of the system to determine wear of posterior fillings three-dimensionally has been shown. Gypsum replicas of restored teeth were evaluated. The tooth surfaces were scanned with a resolution of 250,000 surface points within a measuring time of 20 to 40 sec. The results show that the precision and accuracy of 3-D data acquisition depend on the surface inclination. Up to an angle of 60 degrees, the precision is better than 3 microns, and the accuracy is better than 6 microns. If exact repositioning of the object before and after occlusal loading is possible, e.g., with in vitro studies, differences on the surface can be determined with a precision of 2.2 microns. In reference-free measurements, which are a necessity in clinical studies, the 3-D data acquisition in combination with the automatic matching program can detect wear with an accuracy of 10 microns. The application of this measuring device for the detection of wear of a composite filling functioning in the mouth has been shown. Since this measuring technique is automated, and measurements of high accuracy can be attained in a short period of time, this system offers the possibility for complex analyses of three-dimensional wear to be conducted on a large number of samples in clinical studies. PMID- 9372802 TI - Surfing the Internet: access, use, and implications. PMID- 9372803 TI - Environmental turbulence: staff nurse perspectives. AB - The purpose of this qualitative study was to explore staff nurses' perceptions of how turbulence in the internal environment affected their ability to provide patient care. The themes that emerged from the data point toward multiple factors impinging on a staff nurse's ability to provide quality care in today's healthcare environment. The authors discuss these factors, the consequences for staff nurses, patients, and the organization, and the implications for nursing administrators and their colleagues in hospital administration. PMID- 9372804 TI - The effects of palliative care on patient charges. AB - Palliative Care Teams (PCTs) could be an answer for providing care for the hopelessly ill patient without accumulating high costs. The authors discuss their examination of the relationship between the implementation of a PCT and patient charges. Data indicated that daily charges were reduced significantly after the implementation a PCT. PMID- 9372805 TI - Understanding the unmanageable nursing unit with casemix data. A case study. AB - The unmanageable nursing unit is one that has the reputation of being wastefully over budget, not using nursing resources well, not cost effective, and certainly not well managed. Serendipity led us to discover ways to understand the unmanageable unit in one institution. The nurse manager knew the unit was not working well, but had no way to describe this in clinical management terms that would be understood by others. When data from before and after major structural and system redesign initiatives became available, they showed a situation in which decisions were made without data that worked. How much better might it have been had the data that was now accessible been used? We suggest a design for using standard hospital data to define alleged problems of inefficient nursing units, the design is also the structure for monitoring the effects of management changes. PMID- 9372806 TI - Nurse manager perceptions of healthcare executive behaviors during organizational change. AB - Nurse managers have a large responsibility in implementing healthcare organizational change. To be effective, they need support from healthcare executives. The authors report on a study in which nurse managers described behaviors that facilitated the quality of their work life. Nurse managers in a large (700+ bed) hospital undergoing organizational change were asked to rank behavior of healthcare executives perceived as supportive to a successful transition process and related to maintaining quality of work life. The nurse managers in this study ranked frequent communication about the goals and progression of the organizational change by healthcare executives as most important during a time of organizational change. High visibility and verbalized commitment to the organizational change being implemented were indicated as important by the managers responsible for the operation and realization of the desired vision and goals. Behaviors exhibited by healthcare executives during a time of organizational change may be supportive to nurse managers. PMID- 9372807 TI - Are hospital incidents being reported? AB - Risk management and quality improvement measures assume that staff recognize and report individual hospital incidents. A survey of nurses working in acute care hospitals in 15 localities across a south-eastern state was conducted to explore nurses hospital incident reporting behaviors and supervisors beliefs about and use of incident reports. Nurse managers may have reason to be concerned about this quality measure: the number of incidents documented may represent only a portion of all incidents. PMID- 9372808 TI - Venous disorders--reflections of the past three decades. PMID- 9372809 TI - Where does venous reflux start? AB - PURPOSE: This study was designed to identify the origin of lower limb primary venous reflux in asymptomatic young individuals and to compare patterns of reflux with age-matched subjects with prominent or clinically apparent varicose veins. METHODS: Forty age- and sex-matched subjects with no symptoms (age, 15 to 35 years; 80 limbs; group A), 20 subjects (age, 19 to 32 years; 40 limbs) with prominent but nonvaricose veins (n = 26 limbs; group B), and 50 patients (age, 17 to 34 years; 100 limbs) with varicose veins (n = 64; group C) were examined with color flow duplex imaging. All proximal veins (above popliteal skin crease), superficial, perforator, and deep, in the lower limb were examined in the standing position, and all the distal veins in the sitting position. Patients who had a documented episode of superficial or deep vein thrombosis, previous venous surgery, or injection sclerotherapy were excluded from the study. RESULTS: The prevalence of reflux in group A was 14% (11 of 80), in group B 77% (31 of 40), and in group C 87% (87 of 100). In more than 80% of limbs in the three groups, reflux was confined to the superficial veins alone. Deep venous reflux or combined patterns of reflux were uncommon even in group C. Reflux was detected in all segments of the saphenous veins and their tributaries. In the 125 limbs that had superficial venous incompetence, the below-knee segment of the greater saphenous vein was the most common site of reflux (85, 68%), followed by the above-knee segment of greater saphenous vein (69, 55%) and the saphenofemoral junction (41, 32%). Nonsaphenous reflux was rare (3, 2.4%). Reflux in the lesser saphenous vein (21, 17%) was seen in all groups, whereas involvement of both greater and lesser saphenous veins (8, 6.4%) was seen in group C alone. The incidence of multisegmental reflux was significantly higher in group C (61 of 64, 95%) than in group A (two of 11, 18%) or group B (14 of 26, 54%). The prevalence of distal reflux was comparable in all groups. CONCLUSIONS: Primary venous reflux can occur in any superficial or deep vein of the lower limbs. The below-knee veins are often involved in asymptomatic individuals and in those who have prominent or varicose veins. These data suggest that reflux appears to be a local or multifocal process in addition to or separate from a retrograde process. PMID- 9372810 TI - Prevalence and clinical significance of posterolateral thigh perforator vein incompetence. AB - PURPOSE: Posterolateral thigh perforator (PLTP) veins are part of the lateral thigh venous system, which in most people remains undeveloped. This study was designed to determine the prevalence and clinical significance of these veins. METHODS: Over the past 6 years, 2820 lower limbs with signs and symptoms of chronic venous disease (CVD) were evaluated for venous reflux using color flow duplex imaging. Superficial, perforating, and deep veins were examined in the standing, sitting, and reversed Trendelenburg positions. PLTP veins were best identified in the standing position with the patient facing away from the examiner. RESULTS: Twenty-six incompetent PLTP veins were found in 24 limbs (0.85%) of 21 patients (mean age, 43 +/- 16 years; range, 22 to 77 years). All PLTP veins pierced the fascia lata 12 to 25 cm (mean, 16 +/- 3 cm) above the popliteal skin crease in the lateral aspect of the thigh. At this level, the PLTP veins dove posteriorly 3 to 8 cm to join primarily tributaries of the deep femoral vein, superficial femoral vein, or both. Eight PLTP veins were duplicated at 1 to 2 cm below the fascia. Seven PLTP veins gave rise to superficial tributaries that were extended to the lower lateral and posterior thigh, whereas the remaining 19 PLTP veins gave rise to tributaries alongside the lesser saphenous vein and the anterior arch of the greater saphenous vein. On nine occasions, reflux was found in the PLTP veins and their associated tributaries alone. In all of these cases, reflux was adequately controlled with a tourniquet placed distal to the fascial defect. In the remaining 17 PLTP veins, reflux was also seen in the greater saphenous vein, the lesser saphenous vein, or both. None of the limbs that had PLTP vein reflux alone exceeded CVD class 3. When PLTP vein reflux was combined with saphenous reflux, there were five limbs classified as CVD class 4 and one limb each as CVD classes 5 and 6. Twenty limbs underwent ligation and stripping of the varicosities. Three of the earlier patients in the series underwent incomplete operations, which resulted in immediate residual varicosities from the PLTP tributaries. All three patients underwent reoperation successfully within a year. CONCLUSIONS: The prevalence of PLTP vein reflux is quite low. Reflux in the PLTP veins alone is associated with mild to moderate clinical presentation. However, when it is combined with saphenous reflux skin damage can be present. Failure to recognize PLTP veins may result in an incomplete or unnecessary operation, leaving the patients with residual varicose veins. PMID- 9372811 TI - Early outcome after isolated calf vein thrombosis. AB - PURPOSE: The clinical significance of isolated calf vein thrombosis (CVT), particularly with respect to development of the postthrombotic syndrome, remains controversial. The purpose of this study was to define the early natural history of CVT in relation to persistent lower extremity symptoms, propagation, recanalization, and the development of valvular incompetence. METHODS: Over a 116 month period, 499 patients with acute deep venous thrombosis (DVT) were referred to our research laboratory, of whom 58 (12%) had thrombosis confined to the calf veins of at least one extremity. The lower extremities of 268 patients (29 with isolated CVT) were followed-up clinically and with duplex ultrasonography at intervals of 1 day, 7 days, 1 month, every 3 months for the first year, and yearly thereafter. RESULTS: Seventy percent of extremities with CVT were symptomatic at presentation. Although the prevalence of clinical signs and symptoms decreased to 29% by 1 month, 23% of patients had persistent pain, edema, or both at 12 months. In contrast, 9% of uninvolved extremities contralateral to a CVT and 54% of extremities with proximal DVT remained symptomatic at 1 year (p = 0.004). Recanalization proceeded rapidly such that the mean thrombus load was reduced by 50% at 1 month and to zero at 1 year. The prevalence of valvular incompetence progressively increased such that reflux was present in 24% of extremities at 1 year. Although its investigation was not a primary goal of this study, pulmonary embolism was diagnosed at presentation and during follow-up in 11% and 3% of patients, respectively. CONCLUSIONS: The natural history of CVT is complicated by persistent symptoms and the development of valvular incompetence in approximately one-quarter of patients. This potential for persistent lower extremity symptoms should be considered in evaluating the clinical relevance of isolated calf vein DVT. PMID- 9372812 TI - Noninvasive venous testing in the diagnosis of pulmonary embolism: the impact on decisionmaking. AB - PURPOSE: To characterize the use and utility of lower extremity noninvasive venous testing (NIVT) in the diagnosis of pulmonary embolism (PE). METHODS: The study is a retrospective case series of consecutive patients in whom PE was suspected who were referred to a large, urban tertiary care center for NIVT. The main outcome measures of the study were the rate of positive results of NIVT, the amount of new information provided by NIVT, and the frequency of management changes that were attributable to NIVT. RESULTS: Forty-one of 450 patients (9%) had deep venous thrombosis (DVT) by NIVT. The prevalence of DVT by NIVT among patients not evaluated by ventilation/perfusion (V/Q) scanning was 8%. The prevalence of DVT by NIVT among patients with a high-probability V/Q scan result before NIVT was 39%, but no management decisions in this group were based on a positive NIVT result and only two decisions were based on negative NIVT results. The prevalence of DVT according to NIVT among patients who had a negative "diagnostic" (low, or very low probability, or normal) result of V/Q scan before NIVT was 2%. The overall frequency of management changes attributed to NIVT was only 2.5%. In the remaining 97% of patients, management was determined by the result of V/Q scanning or of subsequent pulmonary arteriography. CONCLUSIONS: In patients in whom PE is suspected, results of NIVT are usually negative for acute DVT. Management decisions are almost always based on V/Q scan or results of pulmonary arteriography and not on NIVT. The utility of NIVT to identify DVT in these patients appears limited, and a more selective approach to its application for the diagnosis of PE should be considered. PMID- 9372813 TI - Screening for asymptomatic deep vein thrombosis in surgical intensive care patients. AB - PURPOSE: To identify the presence of occult deep vein thrombosis (DVT) in surgical intensive care unit (SICU) patients and to avoid unnecessary screening, we reviewed our experience with routine duplex screening for DVT in SICU patients. METHODS: Over a 24-month period, all patients who were admitted to an SICU with an anticipated length of stay greater than 36 hours were studied to determine the prevalence of risk factors for asymptomatic proximal DVT. Risk factors, demographics, and operative data were collected and analyzed with multilinear regression, t tests and chi 2 analysis. RESULTS: There was a 7.5% prevalence of major DVT in the 294 patients studied. APACHE II scores (14.5 +/- 6.24 vs 10.3 +/- 3.15; p < 0.0001) and emergent procedures (45.5% vs 23.2%; p > 0.0344) were associated with DVT by multifactorial analysis. Age was significant by univariate analysis. An algorithm based on the presence of any one of the three risk factors identified (APACHE II score 12 or more; emergent procedures; or age 65 or greater) could be used to limit screening by 30% while achieving a 95.5% sensitivity for identification of proximal DVT. CONCLUSION: Absence of all three risk factors indicates a very low risk for DVT (1.1%). Screening of SICU patients is indicated because of a high prevalence of asymptomatic disease. Patients who have proximal DVT require active therapy and not prophylaxis. Costs and resources may be contained by using the above risk factors as a filter for duplex screening. PMID- 9372814 TI - Limb asymmetry in titanium Greenfield filters: clinically significant? AB - PURPOSE: The purpose of this study was to determine the outcomes for patients with titanium Greenfield vena caval filters (TGFs) and, in particular, to evaluate the effect of filter leg distribution on recurrent pulmonary embolism (PE) and caval occlusion. METHODS: Physical examination, abdominal plain films, and duplex ultrasound examinations of the inferior vena cava and lower extremities were obtained annually and recorded in a Filter Database. RESULTS: Seven hundred eighty-three TGFs have been placed since 1989. Follow-up was available for 373 patients, or 65% of the surviving patients, over 1 to 84 months (mean, 33 months). Asymmetry was identified in 42 placements (5%), and 35 of these patients had at least one follow-up examination. The overall incidence of recurrent PE was 3.2% (12 of 373), whereas the caval patency rate was 97.8% (265 of 271). These outcomes were not significantly different for patients who had asymmetric filters (p = 0.1 and 0.18, respectively). CONCLUSIONS: Filter leg distribution does not appear to be associated with an increased incidence of recurrent PE or caval occlusion. These data support earlier in vitro findings. The long-term results with the TGF are comparable with the results of the original stainless steel Greenfield filter. PMID- 9372815 TI - Helical computed tomography of the normal thoracic outlet. AB - PURPOSE: This study was performed to determine the detailed anatomy of the thoracic outlet in normal subjects using helical computed tomography (CT), with particular attention to vascular compression with arm movement. METHODS: Ten volunteers underwent detailed clinical evaluation and helical CT scanning of the upper thorax and neck with the arm in a neutral position and with the arm abducted 90 degrees or greater and externally rotated. Anterior scalene-clavicle distance (SC), costoclavicular distance (CC), and vessel diameters were measured with electronic calipers in each position. Comparisons were made with Student's t test. RESULTS: With abduction the SC decreased from 18.4 +/- 3.9 mm to 5.2 +/- 2.4 mm (p < 0.001), and the CC decreased from 12.6 +/- 2.7 mm to 6.3 +/- 3.3 mm (p = 0.005). At these same anatomic planes, the vein diameter decreased from 11.0 +/- 1.6 mm at the neutral position to 5.1 +/- 1.5 mm (p < 0.001) and from 16.1 +/ 3.0 mm to 7.4 +/- 2.6 mm with the arm abducted (p < 0.001). The artery diameter changed from 6.6 +/- 0.8 mm to 6.2 +/- 0.5 mm (p = 0.08) and from 7.2 +/- 0.8 mm to 6.0 +/- 0.5 mm (p = 0.001) with arm movement. CONCLUSIONS: Both the distances between the anterior scalene muscle and the clavicle and between the clavicle and the first rib are significantly reduced with abduction of the upper extremity. Venous compression is universal at both the SC and CC spaces in normal subjects with this maneuver. Arterial narrowing occurs less frequently and appears to be minor. Minor changes in these thoracic outlet dimensions (SC/CC) may produce venous compression without movement. PMID- 9372817 TI - Ultrasonographic assessment of ambulatory venous pressure in superficial venous incompetence. AB - PURPOSE: In spite of its invasiveness, measurement of ambulatory venous pressure (AVP) is widely considered the gold standard measurement of venous function. We studied a technique for noninvasive ultrasonographic AVP determination in superficial venous incompetence. METHODS: A linear relationship between venous pressure (measured by echo-guided venous puncture) and diameter (measured by transverse axis duplex imaging) was preliminarily demonstrated with multiple measurements in different conditions (supine, sitting, standing, and Trendelenburg positions, after exercise with and without cuff occlusion) in a saphenous tract at the thigh of 82 limbs in which reflux had been previously demonstrated. Then AVP was measured in another group of 44 patients who had demonstrated superficial venous incompetence, both with and without proximal occlusion, using again the same invasive method and a new noninvasive technique. The latter technique consisted in the construction of a linear diameter/pressure curve obtained after saphenous diameter (by high-resolution sonography) and noninvasive pressure (using hydrostatic values) determinations in the sitting and standing positions. Further measurement of saphenous diameter after standardized exercise permits extrapolation of the AVP values from the curve. RESULTS: Linear regression analysis demonstrates that (1) beginning from 20 mm Hg, the pressure/diameter relationship of the incompetent greater saphenous vein is linear; and (2) AVP values derived invasively and noninvasively are significantly correlated (r = 0.7347 and p < 0.0001 for AVP derived without occlusion; r = 0.7270 and p < 0.0001 for values recorded with occlusion). CONCLUSIONS: The proposed technique appears able to reliably assess noninvasively AVP values in superficial venous incompetence. In addition, it can be performed with equipment that is widely used for vascular investigations. PMID- 9372816 TI - Morphometric assessment of the dermal microcirculation in patients with chronic venous insufficiency. AB - PURPOSE: Ultrastructural assessments of the dermal microcirculation in patients with chronic venous insufficiency have been limited to qualitative morphologic descriptions of venous ulcer edges or venous stasis dermatitis. The purpose of this investigation was to quantify differences in endothelial cell structure and local cell type with emphasis on leukocytes and their relationship to arterioles, capillaries, and postcapillary venules (PCVs). METHODS: Two 4.0 mm punch biopsies were obtained from areas of dermal stasis skin changes in the gaiter region of the leg, as well as from noninvolved areas of skin in the ipsilateral thigh, from 35 patients: CEAP class 4 (11 patients), class 5 (9 patients), class 6 (10 patients), and five normal skin biopsies from patients without chronic venous insufficiency. Electron microscopy was performed on sections at 6700x and 23,800x magnification. At 6700x endothelial cell thickness was determined, and the number of fibroblasts, leukocytes, and mast cells were recorded relative to their proximity to arterioles, capillaries, and PCVs. Similarly, at 23,800x endothelial cell vesicle density, interendothelial junctional widths, and basal lamina thickness (cuff width) were measured. Preliminary evaluation for the presence of transforming growth factor-beta 1 (TGF-beta 1) was performed on three patients using reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Quantitative measurements demonstrated increased mast cell content for class 4 and 5 patients around arterioles and PCVs and increased macrophage numbers for class 6 patients around PCVs (p < 0.05). Fibroblasts were the most common cells observed; however, no differences were demonstrated between groups. No differences were observed in interendothelial junctional widths or vesicle densities in arterioles, capillaries, or PCVs. Basal lamina thickness was increased only at the capillary level (p < 0.05). The results of RT-PCR for TGF beta 1 messenger RNA were positive in the three patients studied. CONCLUSIONS: Our data suggest that (1) mast cells play a role in the pathogenesis of chronic venous insufficiency; (2) the effects of mast cells, macrophages, or both may be mediated in part by TGF-beta 1; and (3) capillary cuff formation is not associated with widened interendothelial gap junctions, but may be a result of enhanced vesicular transport rate or conformational changes in the interendothelial glycocalyx. PMID- 9372818 TI - Hemodynamic evaluation of foot venous compression devices. AB - PURPOSE: Venous compression devices effectively prevent deep venous thrombosis. Recently, because traumatic injury of the limb often precludes application of calf devices, newer methods have been developed that are only applied to the foot. This study was designed to evaluate the venous hemodynamic effects produced by four different compressive devices compared with calf-only intermittent pneumatic compression (IPC). METHODS: Twenty-seven healthy volunteers had application of each device followed by duplex scanning determination of the venous hemodynamics at the popliteal vein (PV) and the common femoral vein (CFV). Endpoints included (1) resting (peak) systolic velocity (RSV); (2) maximum venous velocity (MVV) during device activation; (3) acceleration, the slope of the line from RSV to MVV; and (4) return time (RT) from MVV back to RSV. The devices evaluated included two commercially available mechanical foot devices, (1) foot compressive device (FCD1), and (2) FCD2; (3) an experimental mechanical foot device (FCD3); (4) an experimental pneumatic foot device (FCD4); and (5) a calf only IPC device (IPC). RESULTS: The RSV was higher in the CFV than the PV. The initial RSV was not statistically significant between the five experimental groups (p = 0.37) at either the PV or CFV, although the RSV was higher in the CFV than in the calf (CFV, 24.3 +/- 6.7 cm/sec; PV, 12.5 +/- 3.7 cm/sec; p < 0.0001). MVV was significantly higher with FCD2 and the IPC (p = 0.0002) at the PV level, but this difference decreased at the CFV. Acceleration was greatest with the two available foot devices, FCD1 and FCD2, compared with the other three devices (p < 0.0001) at both levels. On the other hand, the RT was significantly longer only with the IPC; RT was four to 10 times slower at the PV and three to five times slower at the CFV compared with the other four devices. CONCLUSIONS: The two commercially available foot devices, FCD1 and FCD2, and the IPC produced significant alterations in venous hemodynamics. Changes produced at the PV level by both foot and calf devices were seen proximally at the CFV, although the changes were usually less. The mechanical devices produced rapid acceleration of venous flow to an elevated MVV, whereas the IPC produced an elevated peak with a sustained period of flow above baseline (RT). Further clinical comparison should be completed before widespread adaptation of these devices as an equivalent to existing IPC devices. PMID- 9372819 TI - "Bull's-eye" sign on gadolinium-enhanced magnetic resonance venography determines thrombus presence and age: a preliminary study. AB - PURPOSE: Venous thrombosis is associated with a significant inflammatory response, which can be visualized by gadolinium magnetic resonance venography (MRV). Gadolinium extravasates into tissue during inflammation, producing perithrombus enhancement on magnetic resonance scanning. This study determines (1) whether gadolinium enhancement occurs during deep venous thrombosis (DVT); and (2) whether this enhancement changes with time and can therefore establish the age of thrombus. METHODS: Patients with a diagnosis of iliofemoral DVT by duplex ultrasound who were referred for MRV to document central thrombus extent were studied. T1 weighted images were obtained before and after gadolinium injection (0.1 mmol/kg); repeat scans were obtained up to 3 months thereafter. At the level of maximum thrombus, measurements of signal intensity were made at the periphery (rim), and the center of the thrombosed vein, as well as the contralateral normal vein, on images after gadolinium enhancement. Rim-center vein signal intensity ratios were then calculated and followed. RESULTS: A total of 39 scans were obtained in 14 patients (eight men, six women). The thrombosed veins were enlarged, with a peripheral rim of enhancement ("bull's-eye" sign). The rim-center ratio for thrombosed veins (2.16 +/- 0.18) was different from that of normal veins (0.66 +/- 0.10; n = 39; p < 0.001). For all acute studies (< or = 14 days) the rim-center ratio was 2.38 +/- 0.17 (n = 31), whereas for all chronic studies (> 14 days) the rim-center ratio was 1.29 +/- 0.44 (n = 8; p = 0.001). Among patients who underwent both early and late studies, the rim-center ratio dropped significantly, from 2.33 +/- 0.20 acutely to 1.29 +/- 0.44 in chronic studies (n = 8; p = 0.03). One patient with active malignancy had a paradoxic increase in rim-center ratio over time and a clinical recurrence of symptoms, suggesting active thrombosis. CONCLUSIONS: We conclude that (1) a pattern of peripheral gadolinium enhancement (bull's-eye sign) is seen around acutely thrombosed veins on gadolinium-enhanced MRV, facilitating DVT diagnosis; and (2) the ratio of signal intensity at the rim versus the center of the thrombosed vein may be a good discriminator of acute compared with chronic DVT, which may help direct therapy. PMID- 9372821 TI - Mechanical characteristics of lyophilized human saphenous vein valves. AB - PURPOSE: We investigated the mechanical characteristics of lyophilized human saphenous vein valves to determine their suitability for use as allogeneic transplants to treat chronic venous insufficiency. METHODS: Fresh cadaveric veins were lyophilized in vacuum bottles within 24 hours of harvest and were stored at room temperature. The veins were reconstituted in saline solution and then were placed in an in vitro flow circuit for evaluation. At varied flow rates, pressures proximal and distal to valves during prograde and retrograde flow were measured. Valve closure times were determined with Doppler examination and spectral analysis. The valves were also stressed to 350 mm Hg on a separate apparatus. RESULTS: All pressures proximal and distal to the valves remained less than 10 mm Hg during prograde flow. A pressure gradient developed immediately on the reversal of flow. Pressure as high as 200 mm Hg applied against the closed valves was not transmitted beyond the valve. Valve closure times had a mean of 0.31 +/- 0.03 seconds and 0.21 +/- 0.01 seconds for the Doppler examination and spectral analysis, respectively. All valves withstood stress pressures to 350 mm Hg. CONCLUSIONS: The in vitro mechanical characteristics of the valves of lyophilized veins are similar to known values for normal in vivo valves. PMID- 9372820 TI - Experimental repair of venous valvular insufficiency using a cryopreserved venous valve allograft aided by a distal arteriovenous fistula. AB - PURPOSE: To evaluate the patency and hemodynamic impact of a cryopreserved allograft venous valve transplanted to the superficial femoral vein (SFV) of a canine insufficiency model aided by a distal arteriovenous fistula (dAVF). METHODS: Eight greyhounds had intravenous hemodynamic parameters measured (venous filling time [VFT], 90% of venous refilling time [VRT90], and simulated ambulatory venous pressure [AVP]) before (T0) and after complete hindlimb venous valvulotomy (T1) to produce venous insufficiency. Simultaneously, a valve containing vein segment was harvested from the opposite SFV or external jugular vein (n = 1) and cryopreserved. Three weeks later a blood type-matched cryopreserved valve was transplanted to the insufficient SFV aided by a low-flow (n = 4) or high-flow (n = 4) dAVF. The fistula was ligated in 3 to 6 weeks, and venous indexes (T2) were obtained 3 weeks later. Analysis of variances compared the venous indexes at T0, T1, and T2 for statistical significance. Gross and histologic inspection assessed valve integrity. RESULTS: Two valves aided by a low-flow dAVF exhibited thrombosis and scarring. The hemodynamics of the six remaining valves demonstrated normalization of the VRT90, an AVP consistent with insufficiency, and a VFT between normal and total venous insufficiency. The patent valves were normal on gross examination and by histologic examination with signs of normal external healing. CONCLUSIONS: A cryopreserved venous valve allograft transplanted to the SFV of an incompetent hindlimb partially corrects venous hemodynamics. A high-flow arteriovenous fistula most consistently preserves transplant patency. PMID- 9372822 TI - Venous reconstructions using the superficial femoral-popliteal vein. AB - PURPOSE: To demonstrate the feasibility of venous reconstructions with the superficial femoral-popliteal vein (SFPV). METHODS: Seven patients who underwent a variety of major venous reconstructions using SFPV were reviewed in a retrospective, observational study. RESULTS: Three central venous reconstructions (thoracic and abdominal) and four peripheral major venous reconstructions were performed with SFPV autografts. In all patients, the SFPV grafts provided an excellent size match and were of adequate length without the need for enlargement by paneling or spiraling techniques. Postoperative anticoagulation medication was not used. There were no early graft failures, and patency was documented by duplex ultrasound, venogram, or both in all patients at a mean of 20 months follow-up. Venous thromboembolism has not occurred, and lower extremity venous morbidity has been minimal. CONCLUSIONS: The SFPV graft demonstrates versatility and durability in selected patients who require large-caliber conduits for venous reconstruction. Because of its size and availability, the SFPV is an excellent conduit for major venous reconstruction. PMID- 9372823 TI - Treatment of venous malformations by direct injection with ethanol. AB - PURPOSE: Venous malformations (VMs) may be discrete or extensive, and larger lesions may be difficult to remove with surgery. Incompletely removed lesions have a tendency to recur. We report our experience with ethanol ablation of VMs. METHODS: All 12 patients (seven women; mean age, 37 years) were evaluated with magnetic resonance imaging before treatment. A total of 19 prior surgical excisions had been performed for seven of the patients. Symptoms were present in all 12 patients and included bleeding, pain, swelling, and limitation of exercise. The VMs were present in the lower extremities of seven patients, in the upper extremities of three patients, and in the flank and buttocks in two patients. RESULTS: The 12 patients have undergone 30 injection procedures, with six patients requiring one, three patients requiring two, two patients requiring three, and one patient having undergone 12 treatments. General anesthesia was used in 11 patients. Blood loss was minimal for all procedures, and 28 of the 30 procedures were technically successful. Skin ulceration was seen in approximately half of the treated VMs, all of which healed with local wound care. Focal VMs were injected in six patients and resolved with a single treatment in five patients. Patients were free of symptoms at a mean follow-up of 10 months. Extensive VMs were injected for discrete, symptomatic areas in five patients. These lesions all regressed and were asymptomatic at a mean follow-up of 23 months in all but one patient. However, these lesions required multiple treatments as additional areas became problematic. CONCLUSIONS: Ethanol sclerosis is a well-tolerated, safe, and effective adjunct to the management of VMs. Advantages of ethanol injection include the ability to treat a very localized area without an incision. Conversely, extensive lesions may be palliated as symptoms occur. PMID- 9372824 TI - Presentation and management of venous aneurysms. AB - PURPOSE: Venous aneurysms have been reported to occur in most major veins. These aneurysms may be misdiagnosed as soft tissue masses or as inguinal or femoral hernias. Venous aneurysms of the deep system have been associated with deep venous thrombosis (DVT) and pulmonary embolism (PE). To more precisely characterize these lesions, we reviewed our experience with the disease. METHODS: A retrospective analysis of our experience over 22 years was performed. The presentation and management of these lesions were reviewed and compared with the literature. RESULTS: Thirty-nine venous aneurysms were reported in 30 patients. There were 14 men and 16 women. The patients' ages ranged from 3 to 75 years. Thirty aneurysms were located in the lower extremities, four in the upper extremity, and five in the internal jugular vein. Fifty-seven percent of lower extremity aneurysms occurred in the deep system. Patients' symptoms were a mass (75%) associated with pain (67%) and swelling (42%). Thromboembolism occurred in six patients, DVT in three, and PE in three. Eight of nine patients (89%) who had aneurysms of the superficial venous system had their condition misdiagnosed. Diagnosis was made by phlebography (60%), color flow duplex scanning (27%), continuous-wave Doppler scanning (10%), or magnetic resonance imaging (10%). The aneurysm size ranged from 1.7 to 6.0 cm. Management consisted of tangential excision in five (17%), total excision in 23 (77%), and observation in seven (6%). CONCLUSIONS: Venous aneurysms are unusual vascular malformations that occur equally between the sexes and are seen at any age. Most patients have a painful mass of the extremity, and diagnosis is achieved by radiologic examination. Superficial venous aneurysms of the inguinal region are often misdiagnosed. Thromboembolism is more common in aneurysms involving the deep venous system. Because of their potential morbidity, management should be surgical in the majority of cases. PMID- 9372825 TI - Upper extremity deep venous thrombosis and its impact on morbidity and mortality rates in a hospital-based population. AB - PURPOSE: Although much attention has been focused on lower extremity deep venous thrombosis (LEDVT), there is a relative paucity of data regarding the impact of upper extremity deep venous thrombosis (UEDVT) on morbidity and mortality rates. To increase our knowledge with the latter disease, we have reviewed our experience at our institution with 170 patients who had brachial, axillary, and subclavian vein thromboses. METHODS: Over the past 5 years, UEDVT was diagnosed in 170 patients by duplex scanning. The indications for duplex examination were either upper extremity swelling (95%) or as part of the workup for pulmonary embolism (5%). There were 103 women (61%) and 67 men (39%), with ages ranging from 9 to 101 years (mean, 68 +/- 17 years). The diagnosis was made in 152 patients (89%) while they were admitted to the hospital and in 18 patients (11%) in the outpatient clinic. Risk factors included presence of a central venous catheter or pacemaker in 110 patients (65%), malignancy in 63 patients (37%), concomitant LEDVT in 19 patients (11%), and history of LEDVT in 18 patients (11%). Fifty-six patients (33%) had multiple risk factors, whereas 36 patients (21%) had no obvious risk factor. RESULTS: The 1-month and 3-month mortality rates for the entire study group were 16% and 34%, respectively. Patients who had concomitant LEDVT, were 75 years of age or older, and were not treated with anticoagulation medication had a significantly higher 1-month mortality rate. Patients whose diagnoses were made in the outpatient setting were statistically younger and had a lower 3-month mortality rate when compared with the patients whose diagnoses were made as inpatients. Pulmonary embolism was documented by ventilation/perfusion scan in 12 patients (7%). Although no patient in the group in which UEDVT was diagnosed on an outpatient basis was documented to have a pulmonary embolism and 12 patients (8%) in the inpatient group had pulmonary emboli, this difference was not statistically significant. Anticoagulation medication did not totally prevent pulmonary embolism in this review. All patients were followed-up for between 0 to 49 months (mean, 13 +/- 1 months). No swelling of the affected arm was observed in 145 patients (94%); four patients complained of mild intermittent swelling (2%), and seven patients reported significant swelling (4%). CONCLUSIONS: Contrary to previous reports, these data suggest that UEDVT is associated with a low incidence of postthrombotic upper extremity swelling, but a significant incidence of pulmonary embolism and rate of mortality. This review suggests that UEDVT is at least as serious a disease entity as LEDVT and should be managed as aggressively as LEDVT. PMID- 9372826 TI - Regression of proximal deep venous thrombosis is associated with fibrinolytic enhancement. AB - PURPOSE: Recanalization after acute lower limb deep venous thrombosis (DVT) is well documented, but the precise mechanism and timing of these events has not been well characterized. Regression of DVT has been presumed to result from activation of the endogenous fibrinolytic system. This study was performed to compare measurements of the enzymatic components of the intrinsic fibrinolytic system (tissue plasminogen activator [tPA], plasminogen activator inhibitor [PAI 1]) with the observed morphologic changes in thrombosed venous segments using venous duplex ultrasound scanning (VDUS) at intervals after diagnosis of acute DVT. METHODS: Nineteen patients with acute DVT underwent serial VDUS to assess regression of thrombus at intervals of 1 to 2 weeks, 3 to 6 weeks, 8 to 12 weeks, and 24 to 36 weeks. The extent of thrombus in each limb was quantitated at each interval by VDUS of the residual thrombus present in each of five major axial venous segments: the common femoral, superficial femoral, profunda femoris, popliteal, and tibial veins. Thrombus scores for the group at each interval were compared with baseline scores at diagnosis to calculate the percent residual thrombus. Endogenous fibrinolytic activity was determined at the same intervals by serologic assay of the biologic activities of tPA and its inhibitor PAI-1. RESULTS: Thrombus regression was evident by VDUS at 1 to 2 weeks and progressed such that only 26% of residual thrombus remained at 24 to 36 weeks. Complete resolution of thrombus occurred in 10 of 18 patients (56%) who completed the 9 month study. Baseline mean tPA activity was 0.60 +/- 0.07 IU/ml and increased to 1.31 +/- 0.26 IU/ml at 1 to 2 weeks (p = 0.014). tPA activity remained significantly elevated through the 8 to 12 week interval and returned to baseline at 24 to 36 weeks. PAI-1 activity was elevated relative to an age-matched population at baseline (23.1 +/- 1.8 AU/ml) but remained unchanged throughout the study period. Progression of thrombus was observed in three patients (15.8%). Patients who experienced propagation of thrombus did not have the increased tPA activity that appeared to mark activation of intrinsic fibrinolysis. CONCLUSIONS: Regression of acute DVT begins early and continues for at least 9 months. It is accompanied by significant enhancement of the endogenous fibrinolysis, which appears to be primarily mediated by increased tPA activity. Patients who have thrombus propagation in spite of standard antithrombotic therapy may have failure of activation of endogenous fibrinolysis. PMID- 9372827 TI - Vena cava filter ensnarement and delayed migration: an unusual series of cases. AB - PURPOSE: To review delayed and guidewire-induced morbidity associated with vena cava filters. METHODS: The records from the Johns Hopkins Hospital, a tertiary care referral center, of all patients who had vena cava filter complications from August 1993 through July 1996 were retrospectively reviewed. RESULTS: Five patients had filter migration or ensnarement with a guidewire. One patient had delayed extrusion of a filter strut into the duodenum. Four patients had filters ensnared by guidewires, including one during initial filter placement and one several years after placement. CONCLUSIONS: Delayed complications of vena cava filters should be considered whenever unusual patient signs or symptoms cannot be easily explained, even in the absence of a history of filter placement. To prevent guidewire ensnarement of filters, simple techniques should modify endovascular procedures when vena cava filters are present. PMID- 9372828 TI - Structural determinants of lumen narrowing after angioplasty in atherosclerotic nonhuman primates. AB - PURPOSE: The relationship between lumen narrowing, intimal hyperplasia, and wall remodeling after angioplasty was explored in a nonhuman primate model of atherosclerosis. METHODS: Cynomolgus monkeys (n = 37) used in long-term atherosclerosis studies underwent left iliac artery balloon injury. The uninjured right iliac artery served as a reference segment for intraanimal comparisons. One month later iliac arteries were fixed by perfusion (100 mm Hg) and removed for cross-sectional analysis to determine mean values for lumen area (LA), intimal area (IA), internal elastic lamina area (IELA), plaque burden (IA/IELA), and depth of wall injury. Values for each balloon-injured iliac artery were normalized to the contralateral uninjured iliac artery (percent of control), and linear regression analysis was performed comparing LA with IA, with IELA, and with depth of injury. Comparisons were also made between those arteries that remained dilated 1 month after balloon injury (LA > or = 140%; n = 13) and those that renarrowed (LA < or = 100%; n = 14). RESULTS: For all 37 animals, LA 1 month after balloon injury correlated well with IELA (r = 0.72; p < 0.001) but not with IA (r = 0.10; p = 0.54), suggesting that changes in artery size rather than neointimal mass determined lumen caliber. When comparing arteries that remained dilated (n = 13) with those that renarrowed (n = 14), there were no differences in depth of wall injury (injury depth: 0, no injury; 1, intima; 2, IEL; 3, media; 4, EEL; 2.1 +/- 0.3 vs 1.6 +/- 0.3; p = 0.12), neointimal accumulation (IA, 507% +/- 118% vs. 421% +/- 81% of control; p = 0.55), or plaque burden (IA/IELA, 0.39 +/- 0.04 vs 0.37 +/- 0.06; p = 0.71), respectively. However, wall size defined as IELA was significantly smaller in arteries that renarrowed than in those that remained dilated (IELA, 115% +/- 14% vs 230% +/- 19% of control; p < 0.001). CONCLUSIONS: Restenosis after angioplasty has been attributed to intimal hyperplasia, equating loss of lumen caliber with neointimal mass. The data presented herein suggest that lumen narrowing after arterial wall injury may have little to do with intimal mass per se, but rather that a change in wall caliber or wall narrowing is the cause of restenosis. PMID- 9372829 TI - Popliteal aneurysm presenting as acute thrombosis and ischemia in a middle-aged man with a history of Kawasaki disease. AB - Kawasaki disease is known to cause a vasculitis of small and medium-sized vessels, with subsequent aneurysm formation. Most of the severe manifestations of the disease occur as a result of coronary aneurysm formation. However, many other arteries have been documented to be involved. A case is presented of a middle aged man with a history of Kawasaki disease who had an acute ischemic limb from a thrombosed popliteal aneurysm that formed as a result of the disease. This is the first known case report of Kawasaki disease resulting in delayed lower extremity ischemia. Typical findings of patients with Kawasaki disease are presented, along with a case report and review of the literature. A history of Kawasaki disease is an extremely rare but possible cause of peripheral aneurysms, even in middle-aged patients. PMID- 9372830 TI - Acute upper limb ischemia resulting from cleidocranial dysostosis. AB - A case is reported of a woman with an ischemic arm as a result of damage to the subclavian artery by the clavicular anomaly associated with cleidocranial dysostasis. Only one similar case has been reported previously. PMID- 9372831 TI - Mycotic aneurysm of the palmar arch after endocarditis. AB - Mycotic pseudoaneurysms of upper extremities are an infrequent complication of endocarditis. We describe a case of mycotic pseudoaneurysm of the superficial palmar arch in a patient who had acute bacterial endocarditis. We discuss operative and pathologic findings and briefly review the literature on the subject. PMID- 9372832 TI - Subperiosteal new bone formation in association with vascular graft sepsis. AB - Hypertrophic osteoarthropathy (HOA) is a clinical and radiologic syndrome that consists of periosteal new bone formation, synovitis, and digital clubbing. Secondary HOA has been reported confined to one or two extremities that are perfused by Dacron grafts that have become infected. Herein we include a report of a vascular graft infection that shares some of the clinical features with HOA and a brief review of pathophysiologic theories. We conclude emphasizing that periostitis and other HOA signs and symptoms may play a role as a clue to support the suspicion of vascular graft infection when confusing and vague clinical features are present. PMID- 9372833 TI - Regarding "Comparison of endovascular and conventional vascular prostheses in an experimental infection model". PMID- 9372834 TI - Regarding "Stent deformation and intimal hyperplasia complicating treatment of a post-carotid endarterectomy intimal flap with a Palmaz stent". PMID- 9372835 TI - Chronic effects of smokeless tobacco extract on rat liver histopathology and production of HSP-90. AB - Tobacco consumption is a worldwide problem. The recent increase in the consumption of the smokeless tobacco products (snuff and chewing tobacco) has stimulated interest into the carcinogenic effects of these forms of tobacco. The use of smokeless tobacco products has increased in popularity as the use of cigarettes has become less socially acceptable. For most individuals the use of tobacco is a chronic process. Therefore, the effects of an aqueous extract of smokeless tobacco (STE) in rats following low-dose exposure were examined. Female Sprague-Dawley rats were treated orally with 25 mg STE/kg every other day for 90 days. In order to obtain information regarding the cytotoxicity of STE, the ultrastructural changes occurring in livers of rats following administration of STE were examined under light and electron microscopy. Electron microscopy revealed that in the perisinusoidal spaces an accumulation of indistinct filamentous material occurred following 60 days of treatment, occupying most of the sinusoids. Moreover, the lipids were in a state of disintegration. Significant increases in 90 kDa protein expression were also observed due to chronic treatment with STE. Western blot analysis using a polyclonal mouse antibody against heat shock/stress protein 90 (HSP90) confirmed that the overexpressed proteins were heat shock/stress proteins (HSPs). The HSPs are believed to serve as adaptive or survival functions involving a rapid but transient reprogramming of cellular metabolic activity to protect cells from oxidative damage. PMID- 9372836 TI - A morphological study of liver lesions in Xenopus larvae exposed to 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) with special reference to apoptosis of hepatocytes. AB - Edema formation is a consistent feature of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) poisoning in experimental animals. Xenopus embryos exposed to 200 ppb of TCDD for 5 days from shortly after fertilization to early larval stage developed edema of the head, thorax, and abdomen, including ascites, from several days after the end of exposure. There has been no reports on liver lesions in TCDD exposed anuran larvae. To elucidate the participation of liver in the edema formation, light and electron microscopic alterations in the livers from larvae that developed edema were examined. The marked change induced by TCDD was degeneration of the hepatocytes. Three types of degenerating hepatocytes were distinguished. The first type showed morphological features characteristic of apoptosis, including peripherally aggregated nuclear chromatin and overall cytoplasmic condensation; the cytoplasmic organelles retained their integrity and cytoplasmic blebbing. A considerable number of degenerating hepatocytes undergoing apoptosis and numerous apoptotic bodies derived from hepatocytes were observed by electron microscopy. The second type could not be determined as to which type of cell death it belonged to, and the third type was necrosis. Other alterations consisted of disturbances of the usual meshwork architecture of the liver, enlargements of bile canaliculi and the space of Disse, lipid accumulation, and appearance of phagocytizing macrophages. These morphological alterations in the liver generally correlated with the severity of edema with a few exception. These findings suggest that depressed hepatic function mainly due to hepatocyte death participates in the edema formation. PMID- 9372837 TI - Zonal differences in DNA synthesis activity and cytochrome P450 gene expression in livers of male F344 rats treated with five nongenotoxic carcinogens. AB - Both increased cell proliferation and "altered" CYP gene expression are prominent phenomena associated with liver tumor promotion by nongenotoxic carcinogen treatment. To further characterize these two responses, groups of rats were kept on powdered rat chow diet containing 0.05% phenobarbital (PB) or 0.025% ciprofibrate (Cip) for 8 days or given 8 daily doses by gavage of pregnenolone 16 alpha-carbonitrile (PCN, 150 mg/kg/ml corn oil), 3,3',4,4'-tetrachlorobiphenyl (PCB-MC, 3 mg/kg/ml corn oil) or 2,2',4,4'-tetrachlorobiphenyl (PCB-PB, 7.5 mg/kg/ml corn oil). A minipump was implanted in the rat abdominal cavity to release bromodeoxyuridine (BRDU) 5 days after the start of nongenotoxic carcinogen treatment and the experiment was terminated 3 days later. BRDU-labeled parenchymal nuclei were observed primarily in the periportal area independent of nongenotoxic carcinogen treatment. Treatment with each of the 5 nongenotoxic carcinogens resulted in profound alterations in CYP gene expression at both the transcriptional and translational levels. Expression of CYP1A1, 1A1/2, 3A1, 2B1/2, and 4A immunoproteins demonstrated nongenotoxic carcinogen-specific patterns in both magnitude and zonal distribution. In agreement with the CYP immunoprotein data, treatment with each of the five nongenotoxic carcinogens resulted in a unique composition of mRNAs of CYP2B1, 2B2, 2C6, 2C11, 3A1, 3A2, and 4A1, which were variably increased or decreased relative to the untreated control livers, depending on the treatment. Similarly, the rate and pattern of CYP enzyme-mediated hydroxylation toward testosterone, 17 beta-estradiol, corticosterone, and lauric acid were greatly altered by nongenotoxic carcinogen treatment. According to the zonal distribution patterns of CYP immunoproteins, each hepatocyte in the cell plate from the periportal triad to the central vein has a characteristic and nongenotoxic carcinogen-specific composition of CYP enzymes. Because many endogenous substrates are modulators of DNA and RNA synthesis, intracellular kinetics of endogenous substrates of CYP enzymes in the corresponding hepatocytes could contribute, at least in part, to the differences in gene expression, differentiation, and cell proliferation among the hepatocytes in the cell plate. PMID- 9372838 TI - Vitamins and monothiols efficacy in the restoration of adenosine nucleotide degradation enzymes altered during methylmercury intoxication. AB - Male albino mice were intoxicated with a daily dose of 1 mg/kg of methylmercury chloride (MMC) for 7 days, and were treated thereafter with glutathione, N-acetyl DL-homocysteine thiolactone, vitamin B complex, and vitamin E, either alone or in combinations, for the next 7 days. The animals were sacrificed on the eighth day, with the exception of one group that was kept without toxic exposure for an additional 7 days and sacrificed on the fifteenth day. Brain, spinal cord, kidney, and liver of the animals were examined for changes in adenosine deaminase and 5' nucleotidase. We found a severe inhibition of these enzymes during MMC intoxication and significant recovery during monothiols and vitamins administration, indicating the effectiveness of these agents in methylmercury detoxication. PMID- 9372839 TI - Organochlorine pesticide exposure and thyroid function: a study in human subjects. AB - We examined the serum levels of thyroxine and thyroid stimulating hormone in 103 rural subjects with respect to blood levels of organochlorine pesticide and occupation. We found that 24.3% of study subjects had depleted thyroxine levels in association with significantly lower organochlorine pesticide residues in blood. Sex, nutritional status, thyromegaly, or handling of pesticides in the course of work were not found to be factors contributing to depleted thyroxine levels. PMID- 9372840 TI - Gaseous nitrogen dioxide increases the endogenous synthesis of carcinogenic N nitrosodimethylamine in animals. AB - Inhalation of nitrogen dioxide (NO2) by mice administered orally amidopyrine (AP) and sodium nitrite resulted in increased biosynthesis of N-nitrosodimethylamine (NDMA), as determined by analysis using gas chromatography with thermal energy analyzer detector. These results were also confirmed indirectly in chronic experiments on rats using the system of biomarkers of NDMA formation (single stranded DNA liver damages, alanine-aminotransferase, glutathione-S-transferase, and liver S9 fraction activity). The inhibition of NDMA metabolism by 4 methylpyrazol (4-MP) administration increases the sensitivity of NDMA biosynthesis assay in frozen whole-mouse powder. The results confirm that NO2 can serve as the precursor of nitrosamines. PMID- 9372841 TI - Lead poisoning--a hazard of traffic and industries in Pakistan. AB - We measured blood lead level, hemoglobin, and urinary amino-levulinic acid (ALA) in industrial workers and in individuals exposed to vehicle smoke. Industrial workers and people exposed to traffic smoke had comparatively higher blood lead levels than the controls (p < 0.0001). Similarly, urinary ALA was 3.82 mg/dL in industrial subjects, 3.68 mg/dL in traffic-exposed people, and 0.8 mg/dL in control subjects (p < 0.001). The hemoglobin level was lower in the industrial group and in the traffic exposure group compared with the control group (p < 0.01). Traffic smoke-exposed persons, such as traffic police staff, had higher blood lead level than those handling lead material, Government Transport Service (GTS) workshop staff. The length of exposure showed no relationship with the lead levels. However, a positive correlation was observed between the duration of exposure and urinary ALA in both sample groups. The major signs and symptoms of the population studied included headache, generalized body pain, hypertension, and depression. PMID- 9372842 TI - Opinion: violence, vandalism, and aggressiveness--the influence of the media. PMID- 9372843 TI - Induction and distribution of damage in CHO-K1 and the X-ray-sensitive hamster cell line xrs5, measured by the cytochalasin-B-cytokinesis block micronucleus assay. AB - The micronucleus assay holds promise as a method for determining clastogenic effects of particular agents and for examining relative sensitivities of eukaryotic cells to such clastogens. In the following work, a detailed examination of the induction of micronuclei in radio-resistant Chinese hamster ovary fibroblasts (CHO-K1) and the DNA double-strand break repair-defective daughter cell line, xrs5, was performed. Cells were exposed to gamma-irradiation, bleomycin, etoposide, camptothecin and the restriction endonuclease PvuII. By a simplified statistical analysis of data, information on the expression of chromosomal damage, the distribution of damage and the role of cell cycle effects on damage expression was obtained from a relatively small number of cells. All 5 clastogens resulted in elevated levels of micronuclei in xrs5 compared to CHO-K1. An analysis of the distribution of micronuclei within treated populations revealed differences between the modes of damage. Significant deviation from the expected values indicated that expression of micronuclei does not follow an expected Poisson distribution. The frequencies of binucleated cells indicated micronucleus frequencies do not always correlate with inhibition of cell cycle progression. This work also demonstrates that caution is required in the interpretation of data obtained through micronucleus assays. In particular, it does not appear possible to proscribe simple numerical values of relative sensitivity or clastogenicity based on the relative number of micronuclei induced alone. PMID- 9372844 TI - Interaction between DNA-dependent protein kinase and a novel protein, KIP. AB - DNA-dependent protein kinase (DNA-PKcs) is the only eukaryotic kinase activated by DNA ends. Mutation of DNA-PKcs results in murine severe combined immune deficiency in mice and radiation sensitivity. Both the immune and the radiation defects are due to a failure in double-strand break repair. Biochemical studies indicate that DNA-PKcs kinase activity is stimulated by the presence of the DNA end binding protein. Ku. Autophosphorylation of DNA-PKcs results in its inactivation. Based on these studies, DNA-PKcs is presumed to play a direct and important role in the repair of double-strand breaks, but the details of its role are quite unclear. We have done two-hybrid analysis of this entire protein to identify other proteins with which it interacts. Thus far, extensive analysis has only revealed one strong interaction that satisfies both high genetic and biochemical stringency. The interaction is with a novel human protein that has 26% amino acid identity with the phosphatase component, calcineurin B. We discuss the interaction of DNA-PKcs with this novel calcium-binding protein family member in the context of possible kinase-phosphatase regulation of DNA end joining. PMID- 9372845 TI - A role for p53 in DNA end rejoining by human cell extracts. AB - The tumor suppressor p53 is a major regulator in the response of human cells to DNA damage. In this study we assessed the role of p53 in the repair of DNA double strand breaks in plasmid DNA using cell extracts from three human lymphoblastoid cell lines derived from the same donor. TK6, WI-L2-NS and TK6-E6-5e cells express wild-type, mutated and essentially no p53 protein, respectively. Total cellular extracts from TK6, WI-L2-NS and TK6-E6-5e cells were incubated with EcoRI linearized pUC19 DNA. Southern blot analysis of end-rejoined DNA indicated that the major products formed were linear multimers. There was approximately 2-fold greater end rejoining in WI-L2-NS and TK6-E6-5e extracts compared with TK6 extracts. Total DNA from end-rejoining reactions was purified and used to transform bacteria. Using the lacZ reporter gene as a measure of repair fidelity we found that misrepair, as indicated by white colonies, occurred at 4.1% to 6.5% of transformants, with no significant difference between the three cell lines. Gel analysis revealed that misrepair involved only deletions. Sequence analysis of 11 misrepaired products from each cell line showed 12 different deletions from 4 to 48 bp in length, but each cell line yielded similar product types. These results indicate that total cellular extracts from human lymphoblastoid cells lacking p53 or expressing mutated p53 have increased end-rejoining activity as compared with extracts from cells expressing wild-type p53. However, the p53 status does not influence the ratio of misrepair:correct repair, or the type of misrepair events. PMID- 9372846 TI - Alu-mediated detection of DNA damage in the human genome. AB - A new approach to monitoring UV damage and repair in the human genome has been developed. The proposed approach is based on a combination of features unique to interspersed repetitive Alu elements, and the ability of certain DNA lesions to block Taq polymerase-mediated DNA synthesis: namely, the extraordinary abundance of Alu repeats throughout the human genome in conjunction with distinct sequence motifs comprising long runs of T residues which are likely targets for formation of UV lesions. Hence, Taq polymerase-mediated extension synthesis with Alu specific primers was employed to visualize formation of discrete predicted adducts within the element. Several variations of the Alu-primer driven amplification protocol were developed to monitor the following aspects of damage: (i) induction of UV-photoproducts at predicted sites within the Alu sequence, (ii) modification of extension synthesis profiles, (iii) UV dose dependent, quantitative inhibition of Alu-primer driven amplification. The assays reveal sites of predicted Taq polymerase blockage within the Alu sequence, a global decrease in the mean length of extension products, and a measurable reduction in the quantity of extension products that is inversely proportional to UV dose. Thus, the exceptional abundance of Alu repeats and their primary sequence features, in combination with the ability of UV lesions to block elongation by Taq polymerase, provide a novel and sensitive system for detecting UV damage in the human genome. The system detects UV damage at levels that are compatible with cellular DNA repair, and provides a unique amplification-based protocol for probing the overall integrity of human DNA. PMID- 9372847 TI - Suppressing effects of S-methyl methanethiosulfonate and diphenyl disulfide on mitomycin C-induced somatic mutation and recombination in Drosophila melanogaster and micronuclei in mice. AB - S-Methyl methanethiosulfonate (MMTS) and diphenyl disulfide (DPDS) are temporary enzyme-sulfhydryl blocking agents. They are naturally occurring phytoalexin-like and synthetic substances known to be very potent bio-antimutagens in Escherichia coli B/r WP2. In the present paper, the suppressing effects of MMTS on mitomycin C (MMC)-induced mutant wing spots in the somatic mutation and recombination test (SMART) of Drosophila melanogaster, and of MMTS and DPDS on MMC-induced micronucleated peripheral reticulocytes are described. MMTS consistently reduced the numbers of MMC-induced small single, large single and twin spots per wing at a dose of 10-1000 micrograms/vial, in a dose-dependent manner. MMTS reduced the number of twin spots per wing on the spontaneous mutation at the dose of 1000 micrograms/vial. MMTS and DPDS dose-dependently reduced the frequencies of MMC induced micronucleated peripheral reticulocytes at a dose of 10-40, and 3-100 micrograms/kg, respectively. Our results confirmed that enzyme-sulfhydryl blocking agents, such as MMTS and DPDS, are effective antimutagens in vivo too. PMID- 9372848 TI - Molecular analysis of ERCC2 mutations in the repair deficient hamster mutants UVL 1 and V-H1. AB - The cDNA sequence of the Chinese hamster ERCC2 nucleotide excision repair and transcription gene from the UVL-1 Chinese hamster ovary (CHO) mutant cell line and the V-H1 Chinese hamster V79 mutant line was analyzed. ERCC2 encodes a presumed ATP-dependent DNA helicase and is single copy in CHO lines due to the structural hemizygosity of chromosome 9. Both UVL-1 and V-H1 have intermediate levels of (6-4) photoproduct repair but are as highly UV sensitive as the group 2 mutants that have no detectable repair. Deficiency in cyclobutane dimer removal has also been shown for V-H1. In UVL-1, a single base substitution resulting in an Arg75-->Trp substitution in helicase domain Ia was identified. The equivalent amino acid position is also Arg in the human, mouse, Xiphophorus maculatus, Saccharomyces cerevisiae, and Schizosaccharomyces pombe homologs. In V-H1, a single base substitution resulting in a Thr46-->Ile substitution in helicase domain I (the ATP-binding domain) was identified in both alleles. The equivalent amino acid position is also Thr in the five homologs. Analysis of three V-H1 partial revertants revealed that they still have the original V-H1 mutation in both alleles, indicating that these are second site reversion events. Site specific mutagenesis was used to introduce the Thr46-->Ile, Arg75-->Trp, and Lys48-->Arg (helicase domain I) mutations into a hamster ERCC2 expression plasmid. These plasmids each failed to confer UV resistance to group 2 mutant cells, further demonstrating that the changes identified are the causative mutations in V-H1 and UVL-1. Correlations between specific mutations, biochemical activities, and repair phenotype are discussed. PMID- 9372849 TI - Incomplete complementation of the DNA repair defect in cockayne syndrome cells by the denV gene from bacteriophage T4 suggests a deficiency in base excision repair. AB - Endonuclease V (denV) from bacteriophage T4 has been examined for its ability to complement the repair defect in Cockayne syndrome (CS) cells of complementation groups A and B. CS is an autosomal recessive disorder characterized by hypersensitivity to UV light and a defect in the preferential repair of UV induced lesions in transcriptionally active DNA by the nucleotide excision repair (NER) pathway. The denV gene was introduced into non-transformed normal and CS fibroblasts transiently via a recombinant adenovirus (Ad) vector and into SV40 transformed normal and CS cells via a retroviral vector. Expression of denV in CS A cells resulted in partial correction of the UV-sensitive phenotype in assays of gene-specific repair and cell viability, while correction of CS-B cells by expression of denV in the same assays was minimal or non-existent. In contrast, denV expression led to enhanced host cell reactivation (HCR) of viral DNA synthesis in both CS complementation groups to near normal levels. DenV is a glycosylase which is specific for cyclobutane-pyrimidine dimers (CPDs) but does not recognize other UV-induced lesions. Previous work has indicated that CS cells can efficiently repair all non-CPD UV-induced transcription blocking lesions (S.F. Barrett et al.. Mutation Res. 255 (1991) 281-291 [1]) and that denV incised lesions are believed to be processed via the base excision repair (BER) pathway. The inability of denV to complement the NER defect in CS cells to normal levels implies an impaired ability to process denV incised lesions by the BER pathway, and suggests a role for the CS genes, particularly the CS-B gene, in BER. PMID- 9372851 TI - Development and utilization of the rat lymphocyte hprt mutation assay. AB - Much of the recent progress in the field of genetic toxicology has come from an increased understanding of the molecular and cellular biology of the mammalian organism. Most prominent has been the ability to detect and quantify somatic mutation and relate the nature of the mutation to the specific type of chemical damage. Building upon the foundation of the human lymphocyte hypoxanthine guanine phosphoribosyl transferase (hprt) system, and later, the mouse hprt system, methods for the detection and quantification of hprt mutations in rat lymphocytes were developed. These methods are described in this report as is the ongoing validation of the assay. Additionally, the characterization of the recovered mutants and a comparison of the mutation spectrum in the rat lymphocyte system to the spectrum in cancer genes, such as H-ras and p53, and the spectrum in transgenic systems, such as lacI, are included. The development of the rat lymphocyte hprt system and validation of the assay at the molecular level, provide an effective and reliable measure of genetic damage in an in vivo system which is readily comparable to measurement of genetic damage in the human. PMID- 9372850 TI - 8-hydroxyguanine (7,8-dihydro-8-oxoguanine) DNA glycosylase and AP lyase activities of hOGG1 protein and their substrate specificity. AB - Recently we cloned a structural human homolog (hOGG1) of the yeast OGG1 (yOGG1) gene that is involved in the excision repair of 8-hydroxyguanine (also known as 7,8-dihydro-8-oxoguanine; oh8Gua), hOGG1 protein shares 38% amino acid identity with yOGG1 protein. In this paper, we define the substrate specificity of oh8Gua DNA glycosylase and AP lyase activities of the hOGG1 protein. The oh8Gua released from oh8Gua containing DNA was measured by analysis with HPLC coupled with electrochemical detector (ECD) and cleavage sites in the DNA were identified by cleavage assay using gel electrophoresis. GST-hOGG1 protein possessed the oh8Gua DNA glycosylase/AP lyase activity and weak delta-elimination activity, oh8Gua opposite the C in duplex oligonucleotide was most efficiently released by GST hOGG1 protein and oh8Gua opposite the T was also released, while oh8Gua opposite the G or A was very slowly done. The rank order of DNA cleavage efficiency was the same as that of oh8Gua glycosylase activity. Glycosylase/AP lyase activities and their substrate specificities of the GST-hOGG1 protein was similar to GST yOGG1 protein but different from MutM protein. These results indicate that the dominant function of hOGG1 protein is a oh8Gua glycosylase reaction by specifically recognizing oh8Gua and pyrimidine opposite the oh8Gua and delta elimination reaction in the same manner as yOGG1 protein. Thus, the hOGG1 gene is a functional human homolog of the yOGG1 gene on oh8Gua excision repair in spite of the low structural identity at amino acid level between hOGG1 and yOGG1 proteins. PMID- 9372852 TI - Review of the genotoxicity of 2-butoxyethanol. AB - The available data on the genotoxicity of 2-butoxyethanol have been reviewed. 2 Butoxyethanol has been examined for genotoxic activity in a range of in vitro and in vivo assays, including the mouse bone marrow micronucleus assay. The in vitro assays used range from well validated and generally accepted assays such as the Salmonella/microsome and in vitro cytogenetic assay, through to less well validated assays such as assessment of the inhibition of metabolic cooperation in V79 cells. The levels of experimental details and data reporting vary across the studies with some papers presenting only limited information. Taking the above factors into consideration, the available data indicate that 2-butoxyethanol has no significant genotoxic activity. This conclusion is also consistent with the chemical structure of 2-butoxyethanol, which is not alerting for likely genotoxic activity. These collected considerations indicate that 2-butoxyethanol is unlikely to be a genotoxic carcinogen to rodents, a prediction that supplements seventeen published predictions of the outcome of the ongoing NTP rodent carcinogenicity bioassays. PMID- 9372853 TI - Genotypic selection methods for the direct analysis of point mutations. AB - Genotypic selection enriches a particular DNA sequence relative to another closely-related DNA sequence based only on a change of one or a few bases. This review is a survey of the genotypic selection methods that have the sensitivity to detect rare point mutations. These methods are primarily being used to study mutations caused by environmental mutagens; however, the ability to detect and measure very minor DNA sequence populations is likely to further research efforts in many fields. The approaches for allele-selection have intrinsic strengths and weaknesses, and vary greatly in sensitivity. The most sensitive method is Restriction Fragment Length Polymorphism/Polymerase Chain Reaction (RFLP/PCR) by which mutant fractions as low as 1 mutant allele in 10(8) wild-type alleles can be detected. The RFLP/PCR approach is presented as a prototype genotypic selection method. Genotypic selection methods are categorized in terms of those that (1) selectively destroy the abundant or wild-type allele, (2) selectively amplify the rare or mutant allele, or (3) spatially separate the alleles. Issues relevant to the further development of genotypic selection methods include initial DNA pool size, strategies to eliminate the bulk of extraneous DNA, the use of an internal copy number standard in quantitative PCR, the fidelity of thermostable DNA polymerases, and the effective use of PCR in linking two or more genotypic selection techniques. We conclude that proficient genotypic selection requires more than one allele-enrichment technique with at least one of these preceding a high-fidelity PCR amplification step. PMID- 9372854 TI - Occurrence of ras mutations in human lung cancer. Minireview. AB - Members of ras family of oncogenes, when activated by a point mutation, have been implicated in many types of human cancers. In several types of human solid tumors, point mutations of the K-ras gene are relatively frequent. Among lung cancers, a subset of non-small cell lung carcinomas, mostly adenocarcinomas, contains activated K-ras. The examination of K-ras mutations in samples obtained for diagnostic reasons, such as bronchial biopsies or bronchoalveolar lavage fluid, may be used as a supplement in the early diagnosis of lung adenocarcinoma. PMID- 9372855 TI - Alcohol intake and risk of breast cancer: the euramic study. AB - To evaluate the association of alcohol intake with the risk of breast cancer in post-menopausal women, we analyzed the data from an international case-control study conducted in five European countries (FRG, Switzerland, Northern Ireland, the Netherlands and Spain). Information on alcohol intake was available in 315 cases and 364 controls. Medians for the tertiles of alcohol intake among current drinkers were 1.7, 6.0, and 20.0 g/day. Adjusted relative risks (and 95% confidence intervals) of breast cancer for each tertile of intake in current drinkers, compared to never drinkers, were 1.00 (0.60-1.67), 1.01 (0.60-1.73), and 1.18 (0.69-2.03). The adjusted relative risk for ex-drinkers was 1.73 (1.07 2.79). Among both current drinkers and ex-drinkers, the relative risk was higher for those with body mass index above the median compared to those with body mass index below the median. These results do not support a dose-response effect of alcohol on breast cancer risk, although consumption levels were too low to exclude increased risk with high regular intake. Further research is necessary to evaluate the risk of developing breast cancer among ex-drinkers and the potential interaction between body mass index and alcohol drinking. PMID- 9372856 TI - Characterization of human breast adenocarcinoma SK-BR-3 cells resistant to doxorubicin. AB - Doxorubicin shows a wide spectrum of activities in solid tumors, especially against breast carcinoma. The aim of this study was to examine if doxorubicin, when given at lower concentrations than applied in clinic, may induce changes in treated cells. With this purpose we developed human breast adenocarcinoma SK-BR-3 cell line resistant to doxorubicin. The sensitivity of these cells to doxorubicin and to some other cytostatics used in cancer treatment was determined by colorimetric MTT assay. Some parameters which may be of importance as prognostic factors in treatment of breast cancer were analyzed as well. The expression of genes involved in mitotic signal pathway (EGF, TGF alpha, EGF-R, erbB-2, erbB-3, c-myc and c-H-ras) was determined immunocytochemically. The concentrations of cathepsins were determined using quantitative immunoreactive assays (cathepsins B and L) or immunoradiometric assay (cathepsin D). The results revealed that even low doses of doxorubicin can induce numerous changes in treated cells: they become resistant to doxorubicin, and cross-resistant to several other cytostatics. The expression of the above mentioned genes involved in mitotic signal transduction, as well as cathepsins D and L, was similar in both parental and doxorubicin treated cells. PMID- 9372857 TI - Prognostic significance of tumor angiogenesis in advanced breast carcinoma: an Indian experience. AB - Angiogenesis is essential for tumor growth and metastasis. In the present study we investigated the prognostic significance of microvessels (MV) density using immunohisto-localization of factor VIII antigen in 51 breast cancer patients. We counted microvessels per 200x field in the most active areas of neovascularization by staining factor VIII related antigen and graded MV density and correlated with stage, LN involvement and histologic grade. Patients who subsequently developed metastases had significantly high MV counts than patients without metastatic disease (p < 0.001). Patients who subsequently died of the disease had significantly high mean microvessels counts than patients who remained alive at the end of 5 years (p < 0.001). As density of factor VIII antigen staining increased the survival decreased (p < 0.001). All the patients having > 25 MV per 200x field had tumor recurrence faster as compared with patients having < 25 MV (p < 0.02). Thus, the MV count correlates with the prediction for metastasis and poor survival. Such an indicator would be useful in selection of a subgroup of patients with breast cancer who are at high risk for having occult metastasis at presentation and subsequently would benefit from aggressive therapy. PMID- 9372858 TI - Surfactant system in lung cancer. Endogenous lipid pneumonia. AB - The aim of the study was the evaluation of endogenous lipid pneumonia-type changes developing in the vicinity of primary tumors of the lungs. The postoperative material collected from 56 patients operated for non-small cell lung cancer was examined. The coexistence of endogenous lipid pneumonia-type changes with squamous cell carcinoma and large cell carcinoma of the lung was most common. Patients with these histopathological types of carcinoma had lower percentage of metastases to the lymph nodes. Endogenous lipid pneumonia was found to accompany most frequently the tumors 3 < or = 6 cm in diameter and it was slightly more common in the vicinity of peripheral tumors. PMID- 9372859 TI - Taxol-enhanced cytotoxic effect of radiation in human promyelocytic leukemia cells: relative resistance of multidrug-resistant HL-60 cells in vitro. AB - Cytotoxic effects of sequential taxol (paclitaxel) and X-irradiation on drug sensitive human cultured promyelocytic leukemia (HL-60) cell line and its multidrug-resistant sublines were examined using photometric MTT test and flow cytometry. Paclitaxel (at concentrations 1-10 nmol) stimulated the cytotoxic effect of irradiation in HL-60 and to a lesser extent also in HL-60/ADR, but not in HL-60/VCR cells. The stimulation of radiation-induced cytotoxic effect by paclitaxel correlated with its potential to induce cell cycle and viability alterations identified with flow cytometric analysis (i.e. increased propidium iodide staining, increased side scatter, decreased forward angle scatter, accumulation of necrotic cell detritus, apoptotic pre-G0 cells and cells in the G2/M phase of the cell cycle). PMID- 9372860 TI - Distribution and photodynamic effect of zinc phthalocyanine disulfonate in nude mice bearing mammary carcinoma. AB - The distribution study of zinc phthalocyanine disulfonate (ZnPcS2) in nude mice bearing mammary carcinoma (T50/80) revealed a rapid uptake of the dye by tumor. In experimental photodynamic therapy (PDT), the tumors were exposed to laser radiation (670 nm, 100 mW/cm2, 150 J/ /cm2) after intravenous administration of ZnPcS2 in saline. The results showed the maximum tumor destruction to be achieved for the time interval between injection of the drug (2 mg/kg) and exposure to laser light of 5 min, while a significantly less damage was observed when the time interval was 24 h (p < 0.0001). The degree of damage produced by the treatment was monitored in vivo by means of noninvasive NMR-imaging and subsequently confirmed histologically. PMID- 9372861 TI - Effects of intracellular chelatable iron and oxidative stress on transcription of classical cellular glutathione peroxidase gene in murine erythroleukemia cells. AB - The effect of intracellular chelatable iron levels and of oxidative stress on nuclear classical cellular glutathione peroxidase (GSHPx-1) RNA nascent chain elongation (run-on transcription) and on the stability of cytoplasmic GSHPx-1 mRNA was investigated in murine erythroleukemia (MEL) cells. The amount of iron in the intracellular low molecular mass iron pool was changed by incubation of MEL cells transformed by Friend virus with iron donors or iron chelators. Transcription in vitro in isolated nuclei from treated cells showed that the treatment with iron chelators (desferrioxamine (DFO), pyridoxal isonictinoyl hydrazone (PIH) decreased the rate of nuclear GSHPx-1 RNA nascent chain elongation in both uninduced and with 5 mmol hexamethylenebisacetamide (HMBA) to erythroid differentiation induced MEL cells. Iron donors (diferric transferrin, Fe-PIH or their combination) and t-butyl hydroperoxide (t-BuOOH) had the opposite effect on GSHPx-1 gene transcription in run-on experiments. On the other hand, 50 mumol DFO or 2.5 mumol t-BuOOH did not change the stability of cytoplasmic GSHPx 1 mRNA in both uninduced and induced MEL cells treated with 5 mumol actinomycin D and with or without these agents for 9 h. These findings indicate that iron and oxidative stress play their role at the transcriptional level of GSHPx-1 gene expression. PMID- 9372862 TI - In vivo tumor necrosis factor-alpha induction following chlorin e6-photodynamic therapy in Buffalo rats. AB - Photodynamic therapy may induce in the in vivo conditions the cytokine tumor necrosis factor-alpha in Buffalo rats. The sensitizer, i.e. chlorin e6, in the doses 2.5, 5.0 and 7.5 mg/kg of body weight followed by light treatment with total doses 50, 100, 150, 200 and 250 J/cm2 resulted in the increase of serum levels of the cytokine. The levels of tumor necrosis factor-alpha have been determined at different time points using enzyme-linked immunosorbent assay (ELISA). In control animals these levels did not exceed the mean value of 189 pg/ml, whereas in photodynamically treated rats the levels were almost 3-4 times higher. The entire experiment has been carried out on healthy animals; control, tumor-bearing rats have also been included to the present experiment. PMID- 9372863 TI - Chloroaceto hydroxamic acid as antitumor agent against Ehrlich ascites carcinoma in mice. AB - In vivo cell growth inhibition of Ehrlich ascites carcinoma (EAC) has been evaluated with chloroacetohydroxamic acid, (CHA), having -CH2 Cl, for the -NH2 group of hydroxyurea (HU). The inhibitory character of CHA against EAC in mice model has been found to be comparable with that of HU. Cell growth inhibition by CHA is accompanied by inhibitions of DNA and protein synthesis of the treated cells. The transplantability of EAC cells treated with a single dose of (100 mg/kg) CHA is found to be reduced. Enhanced intraperitoneal macrophage is observed in normal mice following CHA (100 mg/kg) treatment. Deviations of hematological parameters and alkaline phosphatase (ALKP) activity consequent to tumor growth are found to be recovered in tumor bearing mice treated with CHA. All these studies suggest the importance of CHA for further trial as a potent antitumor agent. PMID- 9372864 TI - Apoptosis update: to be, or not to be, and how to arrange the latter. Meeting review. AB - It has become accepted that cell death is an essential mechanism for the maintenance of an animal's health. But how do cells know when they should die, and how do they do it? A recent conference titled "Programmed Cell Death" was held by the American Association For Cancer Research in Bolton Landing, New York state, USA, on October 19-23, 1996, which focused on the signals that push a cell towards its own self-destruction, and also on the biochemical tools used by these cells in making this ultimate sacrifice. The molecular vocabulary of programmed cell death is only recently being deciphered. At the heart of programmed cell death exists at least one intrinsic program for committing cell suicide, although it is still unclear if there is only one [3]. If only one program exists, it probably contains multiple branches, overlapping pathways, and redundant molecular interactions. One item is clear, however: there exist many mechanisms for inducing cells to suicide. PMID- 9372866 TI - Free and total PSA in the diagnosis of prostate cancer. AB - The use of PSA in the diagnosis of prostate cancer is controversial. This is due to false-positive results caused by benign prostatic hyperplasia (BPH). Different forms of circulating PSA have recently been described. Initial studies indicate that the fraction of free PSA is lower in prostate cancer than in BPH, therefore suggesting that its measurement could be of some diagnostic value. We have assessed the serum value of the percentage of free/total PSA in the differential diagnosis of BPH and prostate cancer. The levels of PSA and free PSA (DELFIA) were measured in 145 BPH patients and 56 prostate cancer patients. Free PSA is a small fraction of PSA, and significantly lower levels are being found in prostate cancer. In those patients with a PSA level between 2 and 25 micrograms/l, the determination of the percentage of free PSA increased the diagnostic efficiency of PSA, while reducing the number of negative biopsies. We conclude that free PSA may be a useful marker for the diagnosis of prostate cancer. PMID- 9372865 TI - lacZ transduction of 9L rat tumor cells without cloning. AB - Several laboratories have introduced the lacZ gene into 9L cells to improve the usefulness of this already popular rat brain tumor model. However, these laboratories were not concerned about possible changes in the phenotypic characteristics of the 9L cell line which can be induced by the selection of lacZ expressing clones. Here, we describe a method for introducing the lacZ gene into 9L cells without selective cloning. The 9L parent cells (passaged the same number of times) and 9L/lacZ cells were compared in a number of tests and found to have the same phenotype. Specifically, they had the same sensitivity to radiation from external gamma or internal beta radiation, the same growth rates with or without frequent media changes and the same patterns of growth in rat brain. We demonstrated that the 9L/lacZ cells could be sorted from dissociated tumors by flow cytometry and the percentage of nonmalignant versus malignant cells determined. These percentages were variable from rat to rat. The colony-forming efficiency could be determined on the basis of whole tumor or, by using the percent of lacZ-positive cells, on the basis of malignant cells in a tumor. These novel approaches should render the 9L tumor model even more useful. PMID- 9372867 TI - Human bone cells stimulate the growth of human breast carcinoma cells. AB - Human breast cancer cells were cultured together with their metastatic target, bone tissue, to analyze possible growth promotion effects. The coculture of human osteosarcoma cells (TE-85) with human mammary carcinoma cells (ZR-75.1) resulted in up to 8.4-fold stimulation of proliferation of the breast tumor cells. Cell contact of the two cultures was permitted through the channels of Nuclepore filters. However, physical contact turned out not to be necessary, since the proliferative stimulus was also mediated by a bone-derived diffusible factor. Conditioned medium (CM), collected from human primary bone cultures, enhanced the rate of proliferation of several breast tissue cell lines (ZR-75.1, BT-20, HBL 100), while some lines were not affected by osteoblast CM. Breast tissue lines responding to bone CM express low to intermediate levels of the c-erbB-2 gene, in contrast to nonstimulated lines, which overexpress the gene. Recent observations of metastatic spread in breast cancer patients suggest a distinctive pattern of secondary tumor distribution in association with c-erbB-2 protein expression. Bone tissue seems to be a preferential target for metastases of c-erbB-2-negative breast tumors. PMID- 9372868 TI - Recognition of a special membrane antigen of squamous cell carcinoma in rats with a monoclonal antibody UB23. AB - This article describes the recognition of a special membrane antigen of the rat squamous cell carcinoma (SCC) by a monoclonal antibody (mAb), UB23, and the characterization of the UB23 antigen expression in the implanted primary and metastatic SCC in rat models. The mAb UB23 was raised against the FF6 tumor, a well-differentiated rat SCC, and it recognized the 120- to 130-kD cell surface antigen in FF6 tumor cells. The UB23 antigen was found in frequently observed small 'basal' cells but not in keratinocytes, and an increased expression was seen in the cells at the interface with peritumoral stroma in both the implanted primary FF6 tumors and metastases. These results indicated that the UB23 antigen is closely related with the cell differentiation and invasion of FF6 cells, and could be useful for analyzing the mechanism of differentiation, invasion and metastasis of SCC in animal models. PMID- 9372870 TI - Changes in tumor vascular permeability in response to experimental radioimmunotherapy: a comparative study of 11 xenografts. AB - Single and fractionated doses of radioimmunotherapy (RAIT) and standard chemotherapy (0.6 mg 5-FU/day and 0.36 leucovorin/day on days 1-5) result in decreases in vascular permeability (VP) in the GW-39 human colonic xenograft. The effect of a single dose of RAIT (MN-14 anticarcinoembryonic antigen, Mu-9 anticolon-specific antigen, PAM-4 anti-MUC-1, RS-7 and RS-11 antiepithelial glycoprotein labeled with 131I) has also been evaluated in 10 other tumors. Fourteen days after a fixed 1,500-cGy dose of RAIT, 3 colonic tumors (LS174T, HT 29 and MOSER) all exhibited decreases in VP (58, 75 and 70%, respectively). Two colonic (LoVo and GS-7) and 1 breast tumor (MDA-468) did not exhibit any change in VP, and 1 lung (CALU-3), 1 cervical (ME-180), 1 pancreatic (CaPan-1) and 1 breast cancer line (ZR-75) exhibited increases in tumor VP (214, 289, 170 and 139%, respectively). The differences in VP response to RAIT do not appear to be related to the type of tumor, the size of tumor or the antigen being targeted by RAIT. The differences in tumor VP response to RAIT are discussed in terms of the ability to achieve significant tumor accretion of a second dose of radioantibody on a multiple-dosing regimen. We have begun to investigate the mechanism(s) which regulate the varying responses of tumor VP to RAIT by assessing the role that nitric oxide plays. Administration of arginine, a substrate for nitric oxide synthase, results in increases in both baseline and RAIT-modified VP in GW-39 and ME-180 tumors. PMID- 9372871 TI - Endocrine evaluation of infertile men. AB - OBJECTIVES: To determine the incidence and type of endocrinologic abnormalities in men undergoing infertility evaluations and the most appropriate testing to detect them. METHODS: A retrospective review of consecutive patients attending two infertility centers was performed. Results of endocrine testing were compared to medical history and physical and laboratory findings to determine whether endocrinologic screening could be limited to a specific subpopulation. RESULTS: Only 99 of the 1035 patients (9.6%) had abnormal endocrine studies upon repetitive testing. The majority of these patients had an isolated elevation of serum follicle stimulating hormone (FSH) levels. Only 1.7% had a clinically significant endocrinopathy that would have had an effect upon disease management. Screening with serum testosterone and FSH levels alone was just as effective as a complete hormonal panel of testosterone, FSH, luteinizing hormone, and prolactin for the detection of clinically significant endocrinopathy. Only 1 patient with a clinically significant endocrinopathy would not have been identified if hormonal screening was limited to only those patients with a sperm density of less than 10 x 10(6)/mL. CONCLUSIONS: Endocrinopathies are a rare cause of male infertility. Endocrine screening of men with sperm counts of less than 10 million/mL with serum testosterone and FSH levels alone will detect the vast majority of clinically significant endocrinopathies. PMID- 9372869 TI - TAG-72-reactive antibody CC49 recognizes molecules expressed by hematopoietic cell lines. AB - Aberrant glycosylation of mucins on the surface of adenocarcinomas leads to exposure of novel tumor-associated epitopes potentially recognizable by the immune system. Monoclonal antibodies (mAbs) have been developed against some of these epitopes. One such mAb, denoted CC49, recognizes the tumor-associated glycoprotein TAG-72. Most adenocarcinomas, including breast, colon, ovarian, prostate, and gastric, express some form of this molecule, recognizable by the CC49 antibody. The widespread distribution of the antigen on transformed cells makes the CC49 mAb a potentially powerful tool in numerous immunotherapy contexts. In the course of our studies with CC49 and certain of its molecularly engineered derivatives, we screened a number of human hematopoietic cell lines for TAG-72 expression by flow cytometry using CC49. We found that the T-cell line, Jurkat, had a higher level of CC49 mAb binding than any of the carcinoma cell lines previously evaluated in our laboratory. In addition, the myelomonocytic cell line Tf-1 and the erythroleukemia cell line K562 were also positive for CC49 mAb binding by flow-cytometric analysis. However, peripheral blood lymphocytes and certain other hematopoietic cell lines were not able to bind the CC49 mAb. Immunoblot analyses of cell extracts from the CC49 reactive lines indicated distinct protein species reactive with the CC49 antibody. In some instances, cells expressing these reactive proteins were susceptible to antibody dependent cellular cytotoxicity using a chimeric derivative of the CC49 antibody. These results indicate that the cell membrane expression of molecules recognized by CC49 extends beyond adenocarcinomas to certain cell lines of hematopoietic origin. PMID- 9372872 TI - Development of a decision-making tool to predict risk of prostate cancer: the Cancer of the Prostate Risk Index (CAPRI) test. AB - OBJECTIVES: To provide a simple and reliable clinical prediction for an individual patient's overall risk of cancer at biopsy by deriving an easily implemented test based on a generalizable model. Four variables are analyzed for inclusion in the model: prostate-specific antigen (PSA) level, digital rectal examination (DRE) results, race, and age. METHODS: Two populations were used to develop and validate the test: a model (n = 633) and an independent, geographically separate, external population (n = 766). Pathology records for patients who underwent prostate biopsy between 1991 and 1995 were reviewed and screened for the presence of PSA and DRE results. Records where age and race could be determined were extracted. Multiple logistic regression was used with an iterative approach to optimize each test factor. The Wald chi-square test, receiver operating characteristic (ROC) curve, and Hosmer-Lemingshaw test were used to evaluate the model's predictive capability in the two populations. RESULTS: The model and external populations were significantly different for racial mix, PSA level, age, and biopsy detection rate, providing diverse populations to validate the test. Within a combined model, PSA, DRE, race, and age all demonstrated independent capability to predict cancer at biopsy. Predictive power of the overall test was high within the model population (ROC 80.8%), with minimal loss of power in the external population. The test demonstrated no significant lack of fit in either population. CONCLUSIONS: Within a combined test, PSA, DRE, race, and age all contribute significantly to prediction of prostate cancer at biopsy in an individual patient. The test depicts individual risk in an easily understood, visually provocative manner and should assist the clinician and patient in reaching a decision as to whether biopsy is appropriate. PMID- 9372873 TI - Nephrectomy and vena caval thrombectomy in patients with metastatic renal cell carcinoma. AB - OBJECTIVES: To report out experience with performing nephrectomy and vena caval thombectomy in patients with metastatic renal cell carcinoma. METHODS: A retrospective review was performed of 15 patients who underwent surgical excision of the primary tumor and a caval thrombus and treatment of concurrent metastases between 1989 and 1995. The sites of metastases included lungs (n = 8), bone (n = 3), bulky retroperitoneal or mediastinal lymph nodes (n = 2), liver (n = 1), and contralateral adrenal (n = 1). The level of caval involvement was suprahepatic in 3 cases, retrohepatic in 2 cases, and infrahepatic in 10 cases. Three patients had an Eastern Cooperative Oncology Group performance score of 0, 11 had a score of 1, and 1 had a score of 2. Median follow-up was 17 months. RESULTS: Median operative time was 6.5 hours and median hospitalization was 10 days. Two patients required re-exploration for postoperative hemorrhage. There were no perioperative deaths. Four patients underwent surgery for resection of solitary metastases (1 lung, 2 spine, and 1 humerus); 2 of the 4 received adjuvant radiotherapy. Two patients received biologic therapy preoperatively, 3 received it both preoperatively and postoperatively, and 6 received it only postoperatively. The median time to initiation of postoperative biologic therapy was 48 days (range 25 to 110). Eleven patients are currently alive, 7 with no evidence of disease at a median follow-up of 17 months (range 6 to 66) and 4 with stable metastases at 14 months (range 4 to 22). Ten of the 13 symptomatic patients had improved performance scores after surgery. Four patients have died from metastatic disease: 2 from rapid progression at 2 and 5 months after surgery and the other 2 at 17 and 42 months. CONCLUSIONS: Nephrectomy and vena caval thrombectomy can be safely performed in selected patients with metastatic disease. Furthermore, in patients receiving biologic therapy, nephrectomy may enable a better quality of life and prolonged survival. PMID- 9372874 TI - Low-grade collecting duct carcinoma of the kidney: report of 13 cases of low grade mucinous tubulocystic renal carcinoma of possible collecting duct origin. AB - OBJECTIVES: To assess the nature of a series of unusual low-grade mucin-producing tubulocystic renal cancers diagnosed at the Mayo Clinic since 1985. METHODS: We reviewed the clinical, radiologic, and pathologic features of 13 unusual low grade renal carcinomas with features most suggestive of collecting duct origin. RESULTS: In 8 cases, the tumor was discovered incidentally. Presenting symptoms in the other 5 patients were similar to those of typical renal carcinoma. Imaging studies and angiography disclosed solid, cystic, or complex masses that were relatively avascular. Pathologic assessment revealed good circumscription, minimal hemorrhage and/or necrosis, minimal tendency to extend beyond the kidney, tubulocystic architecture, a fibrotic interface with adjacent normal renal parenchyma, low nuclear grade, and minimal mitotic activity. Mucin production was noted in all evaluable cases. All tumors expressed keratins AE1/AE3 and/or Cam 5.2. The tumors showed immunoreactivity to antibodies directed against keratin 34 beta E12 (8 of 13 cases), and Ulex Europeus antigen 1 (6 of 10 cases). Follow-up ranged from 12 to 114 months (mean 62). No metastases occurred in 12 patients. One patient died of metastatic carcinoma morphologically identical to the primary renal neoplasm 46 months after his tumor had been misinterpreted as a benign condition. CONCLUSIONS: We believe the tumors described in this article may be of collecting duct origin, representing the low-grade end of a spectrum of cancers arising in collecting duct epithelium. PMID- 9372875 TI - Thin-section helical computed tomography of the bladder: initial clinical experience with virtual reality imaging. AB - OBJECTIVES: To evaluate the application of virtual reality imaging of the bladder (virtual cystoscopy) in the detection of bladder masses. METHODS: Six patients (mean age 61 years, range 43 to 75) with hematuria and positive findings on conventional cystoscopy were studied by means of thin-section helical computed tomography of the air-distended bladder. Using volume-rendering algorithms, interactive intraluminal views of the bladder mucosa were generated (virtual cystoscopy). Results of virtual cystoscopy were compared with those of conventional cystoscopy in each case. RESULTS: Twenty-six (100%) of 26 masses (mean size 1.7 cm, range 0.3 to 6), detected on conventional cystoscopy, were visualized on virtual cystoscopy. Twelve of 26 masses measured less than 1 cm in maximum diameter. All masses were pathologically proven transitional cell carcinomas. Virtual cystoscopy was well tolerated by all patients, and no complications occurred. CONCLUSIONS: Our results indicate that virtual cystoscopy is an accurate technique for detection of intrinsic bladder masses. It may represent a radiologic adjunct to conventional cystoscopy for initial evaluation of patients with hematuria and for surveillance of patients after bladder tumor resection. PMID- 9372876 TI - Nephrogenic adenoma of the bladder in renal transplant and non-renal transplant patients: a review of 22 cases. AB - OBJECTIVES: To review diagnoses of nephrogenic adenoma and in particular to evaluate its association with transitional cell carcinoma (TCC) of the bladder and its relationship to renal transplantation. METHODS: A retrospective review of 22 cases of nephrogenic adenoma (NA) diagnosed between 1989 and 1996 was conducted, 7 of which were in renal transplant patients. Data collected in each case included demographic details, predisposing factors, associated urologic pathology, mode of presentation, cystoscopic finding, management, and follow-up. RESULTS: There was a 3:1 predominance of men. Mean follow-up was 21.4 months (range 3 to 50). Six patients (27%) had one or more recurrences. All 22 patients had some form of previous bladder insult or surgery, including recurrent urine infections, urinary tract instrumentation, placement of ureteric stents, cystodiathermy, and open bladder surgery. Six cases were associated with TCC of the bladder, of which 4 had NA lesions directly over or close to the site of previous fulguration. In 4 patients, there was a temporal relationship between the administration of intravesical doxorubicin hydrochloride or bacille Calmette Guerin (BCG) and the onset of NA lesions. One case was associated with an inverted papilloma that had not been described before. In 7 renal transplant cases, 3 lesions were found contralateral to the side of the ureterovesical anastomosis. All 22 cases were benign histologically, but one NA was found within a low-grade baldder TCC. Nineteen cases were followed up regularly with no malignant transformation. Three patients were lost to follow-up. CONCLUSIONS: This study has demonstrated an association between NA and bladder cancer. Patients with NA, especially those treated with intravesical chemotherapy or BCG, should have regular cystoscopies. Fulguration or transurethral resection appear to be sufficient treatment. No renal transplant patients had vesical TCC and NA simultaneously. Neither immunosuppression nor ureterovesical anastomosis appeared to be a significant predisposing factor in the transplant patients. PMID- 9372877 TI - Primary transitional cell carcinoma in vesical diverticula. AB - OBJECTIVES: To evaluate the treatment and prognosis of primary tumors in bladder diverticula. METHODS: The cases of 611 patients treated for bladder tumors at a single medical center were retrospectively reviewed. RESULTS: Eight patients had primary intradiverticular transitional cell carcinoma. Five patients had Stage Ta tumor, and 3 had Stage T1 tumor. Most patients were treated by local resection and adjuvant intravesical chemotherapy. All patients with initial Ta disease are disease free at the time of this writing. One patient with T1 disease died, 1 patient's disease recurred several times, and 1 patient showed positive cytology without apparent disease. CONCLUSIONS: Superficial intradiverticular tumors may be treated conservatively. Routine cystoscopy for patients with a bladder diverticulum is warranted for early diagnosis of possible intradiverticular tumor. PMID- 9372878 TI - Urinary symptomatology in younger men. AB - OBJECTIVES: We surveyed a "population" of younger men (20 to 49 years old) for lower urinary tract symptomatology and for symptomatology associated with prostatitis. METHODS: A National Guard unit was surveyed by mail with a 58 question urinary symptom questionnaire. Surveys were returned anonymously by mail. RESULTS: International Prostate Symptom Score (IPSS) of 8 or greater was seen in 5% of men in their 20s and rose to 15% of those in their 40s. Approximately 5% (0% to 7%) reported a history of prostatitis. Caffeine caused symptoms in 2% to 13%, while exercise and smoking were not associated with symptoms. Individual prostatitis symptoms were only seen occasionally across this age group. CONCLUSIONS: As measured by the IPSS, urinary symptoms increased during the 20 to 49-year age period. A history of prostatitis in much less common than most nonpopulation studies suggest. PMID- 9372879 TI - Patient attitudes regarding treatment-related erectile dysfunction at time of early detection of prostate cancer. AB - OBJECTIVES: To assess potency rate and patient attitudes regarding erectile dysfunction. METHODS: A multiple choice, self-administered questionnaire distributed to 750 men undergoing testing for early detection of prostate cancer was used. RESULTS: Overall, 33.9% of patients reported either partial or complete lack of erections and 31.1% were not sexually active or active less than once per month. Furthermore, 55.4% would be affected or very affected by lack of erections and 73.6% chose definitive treatment despite a 50% chance of erectile dysfunction. Finally, 47.4% found such treatment-induced erectile dysfunction to be an important or very important problem. When asked to ascribe a quantity of life or period of time that they would be willing to sacrifice to preserve sexual function following treatment, only 15.2% of patients were able to do so, but no consensus could be reached regarding its value. CONCLUSIONS: Reported differences in quality-adjusted life expectancy when screening was compared to no screening and definitive therapy was compared to expectant management are marginal. Therefore, close attention to seemingly minor variables such as existing impotence rate, attitude regarding erectile dysfunction, and willingness to undergo therapy despite its inherent morbidity may substantially reduce or even reverse this reported disadvantage. PMID- 9372880 TI - A precursor form of PSA (pPSA) is a component of the free PSA in prostate cancer serum. AB - OBJECTIVES: Prostate-specific antigen (PSA) is a widely used serum marker for human prostate cancer (PCa). The majority of PSA in serum is present as a complex with alpha-1-antichymotrypsin (ACT). In recent years, the ratio of free (uncomplexed) to total PSA has shown improved discrimination of PCa from benign prostatic hyperplasia. This study examines the nature of the free PSA from detected in PCa serum and shows that some of the uncomplexed PSA is an inactive precursor of PSA (pPSA). METHODS: Western blot analysis was used to detect clipped, fragment forms of PSA in sera and seminal fluid. Hydrophobic interaction chromatography-high performance liquid chromatography (HIC-HPLC) was used to identify forms of PSA present in the free PSA population. Pooled sera was passed over a PSA immunoaffinity column, and the eluted PSA components were further resolved by HIC-HPLC. RESULTS: Western blot analysis of whole sera showed complexed PSA and the intact, approximately 34 kilodalton free PSA. Only negligible levels of clipped or degraded forms of PSA, as found in seminal fluid, were detected. Column fractions measured for uncomplexed PSA using the Tandem-MP free PSA assay showed that about 25% of the free PSA eluted as pPSA beginning at the [-4]amino acid. Studies with purified recombinant [-4]pPSA showed that this proenzyme form is inactive and does not complex with ACT. CONCLUSIONS: These results suggest that the uncomplexed PSA in PCa serum is primarily unclipped PSA that contains a significant fraction of pPSA. PMID- 9372881 TI - Molecular forms of prostate-specific antigen and human kallikrein 2 (hK2) in urine are not clinically useful for early detection and staging of prostate cancer. AB - OBJECTIVES: Prostate-specific antigen (PSA), a member of the human kallikrein (hK) family, is the most important tumor marker for early detection, staging, and monitoring of men with prostate cancer today. However, the sensitivity of serum PSA is not sufficient to be used alone for prostate cancer screening. Recently, it was reported that the serum-to-urinary total PSA ratio improves the detection of men with prostate cancer, especially in men with a serum total PSA level between 4.0 and 10.0 ng/mL. We tested this hypothesis by evaluating the clinical usefulness of this PSA ratio as well as the use of the different molecular forms of PSA and human kallikrein 2 (hK2) in urine for detection and staging of prostate cancer. METHODS: One hundred ten fresh, midstream urine specimens (prostate cancer 62, benign prostatic hyperplasia [BPH] 38, healthy male control 5, women 5) were collected. Serum total PSA, urine total PSA, urinary free PSA, urinary alpha 1-antichymotrypsin-bound PSA, and urinary hK2 levels were determined by monoclonal antibody assays (Hybritech Inc.). The serum-to-urinary total PSA ratio was calculated. RESULTS: The serum-to-urinary total PSA ratio did not accurately distinguish between men with BPH and men with prostate cancer. There was no significant difference between the urinary levels of any of the molecular forms of PSA or hK2 between men with prostate cancer and men with BPH. Among men with prostate cancer, neither urinary hK2 nor urinary levels of any of the molecular forms of PSA correlated with age, pathologic stage, or Gleason grade. CONCLUSIONS: In our study, the serum-to-urinary total PSA ratio did not improve the detection of men with prostate cancer. Furthermore, measurement of the molecular forms of PSA and hK2 in urine did not improve the detection or staging of prostate cancer over serum PSA alone. PMID- 9372882 TI - Deferred treatment of clinically localized low-grade prostate cancer: actual 10 year and projected 15-year follow-up of the Karolinska series. AB - OBJECTIVES: To review the outcome in patients with clinically localized prostate cancer managed conservatively. METHODS: A total of 122 patients with palpable, clinically localized, low-grade prostate cancer diagnosed from 1978 to 1982 at the Karolinska Hospital, Stockholm, Sweden, were prospectively followed in a surveillance protocol followed by treatment when the tumor progressed with symptoms. RESULTS: All patients but one had been observed for 10 years or more. No antitumoral therapy had been given to 58 (48%) patients at follow-up or before death. The chance of being untreated 5 and 10 years after diagnosis, if still alive, was 71% and 43%, respectively. The actual disease-specific survival rate at 10 years was 90%. Of the patients with a possible observation period of 15 years or more, 25% died of prostate cancer (ie, an actual disease-specific survival of 75%). Using a survival plot, the projected disease-specific survival rate at 15 years was 62%. The cumulative incidence of death from prostate cancer increased with possible observation time up to 15 years. CONCLUSIONS: Our data are mature up to 10 years of observation and, based on these data, deferred treatment is a valid option for patients with clinically localized low-grade prostate cancer with a life expectancy of 10 years or less. The data are not definitive beyond 10 years and firm conclusions will be speculative, but our findings indicate that there probably is room for efficacious local treatment in patients with localized prostate cancer and a life expectancy longer than 10 years. PMID- 9372883 TI - Preoperative recombinant human erythropoietin injection versus preoperative autologous blood donation in patients undergoing radical retropubic prostatectomy. AB - OBJECTIVES: In an effort to avoid allogeneic transfusions, many patients scheduled for radical retropubic prostatectomy (RRP) participate in preoperative autologous donation (PAD) programs. Yet, PAD programs are costly, time-consuming, and not without risks. Perioperative administration of recombinant human erythropoietin (Epoetin alfa) also has been shown to reduce patients exposure to allogeneic transfusion. This study sought to compare the costs and transfusion rates associated with either PAD or perioperative Epoetin alfa in patients undergoing RRP. METHODS: The study population consisted of 120 men randomized to one of two treatment groups. Patients in group 1 donated up to 3 U of autologous blood preoperatively, provided that their hematocrit (HCT) was 33% or higher. Patients in group 2 received 600 IU/kg of Epoetin alfa on days -14 and -7 preoperatively, provided that their HCT was 46% or lower. RESULTS: Overall, 107 (89%) of 120 patients underwent RRP. In group 1, 5 (9.6%) of 52 patients received a total of 12 U of allogeneic blood (0.23 U/patient). In group 2, 5 (9.6%) of 52 patients received a total of 10 U of allogeneic blood (0.19 U/patient). Three patients in group 1 but no patients in group 2 experienced an adverse event. The average costs related to PAD and pharmacologic administration per patient were $540 in group 1 and $657 in group 2. Participation in PAD required an average of 5 hours more per patient compared with Epoetin alfa administration. CONCLUSIONS: Preoperative Epoetin alfa therapy is safe, well tolerated, and equally effective as PAD in reducing allogeneic blood transfusion requirements. Epoetin alfa therapy also is comparable in cost to PAD and offers patients greater convenience and less of a time commitment. PMID- 9372884 TI - Anatomic site-specific positive margins in organ-confined prostate cancer and its impact on outcome after radical prostatectomy. AB - OBJECTIVES: The impact of a positive surgical margin in otherwise confined prostate cancer after radical prostatectomy remains unclear. We analyzed the outcome of a large number of patients with organ-confined prostate cancer according to the presence and anatomic site of margin positivity. METHODS: We evaluated 2712 prostatectomy patients with Stage pT2N0 cancer (ie, no evidence of extra-prostatic disease, seminal vesicle or regional node involvement) and no prior therapy who were treated by radical prostatectomy between 1987 and 1995 at Mayo Clinic. A total of 697 patients (26%) had positive margins. To assess the effect of margin status in the absence of treatment, 378 patients with postoperative adjuvant therapy were not considered for the study group: the final group consisted of 2334 patients. RESULTS: Overall, 253 (58%) tumors were positive at the apex and/or urethra, 85 (19%) at the prostate base, 11 (2.5%) at the anterior prostate, and 174 (40%) at the posterior prostate; 89 (20%) had at least two margins involved and 21 (8.3%) had more than two involved. The apex/urethra was the only positive anatomic site in 183 (42%). Five-year survival free of clinical recurrence or prostate-specific antigen (PSA) biochemical failure (postoperative serum PSA of 0.2 ng/mL or more) for patients with a single positive margin was 79% for apex or urethra, 78% for anterior/posterior, and 56% for prostate base. Five-year survival free of clinical recurrence or PSA (biochemical) failure was slightly higher for those with one versus two margin positive regions (77% versus 68%, respectively). Multivariate analysis revealed that positive surgical margins were a significant predictor of clinical recurrence and PSA (biochemical) failure (relative risk [95% confidence interval]: 1.65 [1.24, 2.18]) after controlling for Gleason grade, preoperative PSA, and deoxyribonucleic acid (DNA) ploidy. The effect of margin positivity on recurrence at a specific anatomic site (versus negative margins or positive at a different anatomic site) revealed the prostate base to be the only significant anatomic site when adjusted for grade, PSA, and ploidy. Five-year survival free of the combined clinical or PSA failure end point for those with versus those without positive margins at the prostate base was 56% versus 85%, respectively (P < 0.0001). CONCLUSIONS: Positive surgical margins are a significant predictor of recurrence in Stage pT2N0 cancer, which is independent of grade, PSA, and DNA ploidy. The impact of positive margin status on recurrence-free survival appears to be anatomic and site-specific, with prostate base positivity significantly associated with poor outcome. The benefit of adjuvant therapy based on anatomic site-specific margin positivity remains to be tested in order to optimize recurrence-free survival. PMID- 9372885 TI - Quality of life and sexuality following radical prostatectomy in patients with prostate cancer who use or do not use erectile aids. AB - OBJECTIVES: It is well established that prostate cancer patients undergoing radical prostatectomy may experience disruptive side effects, most notably urinary incontinence and erectile dysfunction. The purpose of this study is to compare relevant outcomes between patients awaiting radical prostatectomy for prostate cancer and patients who already underwent the surgery, taking into account type of prostatectomy and use of erectile aids. METHODS: We compared self reports of global quality of life, sexuality, urinary continence, and physical capabilities in 86 nerve-sparing patients, 89 standard-prostatectomy patients, 74 prostatectomy patients who used erectile aids, and a comparison group of 45 patients awaiting radical prostatectomy. RESULTS: Regardless of type of surgery, use of erectile aid, or preoperative status, most patients reported good quality of life. The best outcomes in sexuality were reported by patients who used erectile aids, who appeared similar in sexuality to patients awaiting surgery. When differences were detected, standard prostatectomy patients who did not use erectile aids scored worse in most areas of sexuality than nerve-sparing patients who did not use erectile aids. There were no differences in frequency of urinary leakage among the three surgery subgroups. CONCLUSIONS: Although most patients reported problems in sexual and urinary function, global quality of life does not appear to be compromised following radical prostatectomy. Findings suggest that postsurgical sexuality differs depending on type of prostatectomy and use of erectile aids, while urinary function is similar across surgery groups. We conclude that erectile aids should be offered routinely to patients who are ineligible for nerve-sparing surgery or experience erectile difficulties following the nerve-sparing procedure. PMID- 9372886 TI - Painful bone metastases in hormone-refractory prostate cancer: economic costs of strontium-89 and/or external radiotherapy. AB - OBJECTIVES: In a prospective randomized Canadian trial, addition of radionuclide strontium (89Sr) to external radiotherapy (ER) was found to prolong the time to further ER by 15 weeks (35 versus 20, P = 0.006) compared to ER alone in patients with hormone-refractory metastatic prostate cancer (HRMPC). The total direct lifetime costs within the Swedish health care system for the following two treatment strategies was estimated as follows: (a) ER initially and in the event of relapse and (b) ER + 89Sr initially and ER in the event of relapse. METHODS: Calculation of lifetime costs was based on the initial total treatment cost and the probability of future treatment costs. In a retrospective analysis, the average cost of a relapse treated with ER alone was calculated from the actual care consumption of 79 consecutive patients from the south of Sweden who received ER because of skeletal pain due to HRMPC. The costs related to ER included skeletal scintigraphy, ER, outpatient visits, inpatients days, and travel to the treatment center. When 89Sr was added, the cost also included the radionuclide and its administration. Costs in Swedish currency (SEK) were based on the regional tariff for 1993 (U.S. $1 = SEK 8.30). RESULTS: The initial cost for one relapse treated with ER alone was estimated to be SEK 31,011 (U.S. $3736) per patient resident within county (close to hospital) and SEK 48,585 (U.S. $5854) per patient resident out of county (far from hospital). The corresponding figure for initial addition of 89Sr to ER was SEK 43,426 (U.S. $5232) and 61,000 (U.S. $7349), respectively. However, comparison between estimated lifetime cost for the two treatment strategies indicated potential cost savings with initial addition of 89Sr to 3% SEK 2720 (U.S. $328) and 7% SEK 11,290 (U.S. $1360), respectively. CONCLUSIONS: Strontium-89 as initial supplement to ER for palliation of pain in HRMPC is beneficial both from the patient and lifetime health service costs perspectives. PMID- 9372887 TI - Oral estramustine and oral etoposide for hormone-refractory prostate cancer. AB - OBJECTIVES: Estramustine and etoposide have been shown to inhibit the growth of prostate cancer cells in experimental models. An in vivo synergism of the two agents, when administered to patients with metastatic prostate cancer refractory to hormone therapy, has been reported. To confirm these results, we administered this combination to a large number of patients with hormone-refractory prostate cancer (HRPC). METHODS: Fifty-six patients with metastatic HRPC were treated with oral estramustine 140 mg three times a day and oral etoposide 50 mg/m2/day for 21 days. Therapy was discontinued for 7 days and the cycle was then repeated. Therapy was continued until evidence of disease progression or unacceptable toxicity occurred. To control for the possible interference of an antiandrogen withdrawal effect, all patients discontinued antiandrogen therapy and were not enrolled in the study unless there was evidence of disease progression. RESULTS: Forty-five percent of 33 patients with measurable soft tissue disease demonstrated an objective response, which included five complete and ten partial responses. Among 52 patients with osseous disease 17% showed improvement and 50% showed stability of bone scan. Thirty patients (58%) demonstrated a decrease of more than 50% in pretreatment prostate-specific antigen (PSA) levels. The median survival of all patients was 13 months. Good pretreatment performance status, measurable disease response, improvement or stability of bone scan, and PSA response were important predictors of longer survival. CONCLUSIONS: We conclude that the combination of estramustine and etoposide is an active and well tolerated oral regimen in HRPC. PMID- 9372888 TI - Prevention of testicular damage by free-radical scavengers. AB - OBJECTIVES: The role of free radicals as mediators of ischemic injury to the testicle has been the subject of much investigation. We studied whether the testicular damage induced in the rat by cadmium chloride (CdCl2) can be prevented by administration of free-radical scavengers. METHODS: Sprague-Dawley rats (n = 45) were divided into 9 groups as follows: a negative control group; two positive control groups, one of which received injection of 1 mg/kg body weight of CdCl2 and the other 4 mg/kg body weight; and six cotreatment groups, each of which underwent one of these three procedures but was concurrently treated with heparin, oxypurinol, or superoxide dismutase (SOD). The damage was assessed by measurement of testicular weight, lactate dehydrogenase-X (LDH-X) activity, and histology. RESULTS: Testicular weight decreased significantly in the positive control groups (P < 0.05) compared to the negative control group, whereas testicular weight in oxypurinol or SOD cotreatment groups did not decrease significantly with the exception of those rats given the higher dose of CdCl2. The results were similar with regard to testicular LDH-X activity and histology. CONCLUSIONS: These findings suggest that CdCl2 induces impairment of testicular function and causes a marked reduction in testicular LDH-X activity; that LDH-X activity is a biological marker of testicular damage; and that, except at high doses of CdCl2, this damage can be prevented by oxypurinol or SOD. PMID- 9372889 TI - Immunologic findings in Peyronie's disease: a controlled study. AB - OBJECTIVES: Recent literature suggests the hypothesis of an immune etiology of Peyronie's disease. In this controlled study, the immune response pattern of the disease is investigated. METHODS: Sixty-six patients with Peyronie's disease and 20 age-matched controls were studied. In all patients, skin test (multitest), in vitro lymphocyte transformation test (LTT), serum immunoglobulin (Ig) A, G, and M, anti-DNA, antinuclear and anti-smooth muscle cell antibodies, C3 and C4 complement fractions, antistreptolysin, and C-reactive protein titers were evaluated. RESULTS: A fair percentage (75.8%) of the patients with Peyronie's disease exhibited at least one abnormal immunologic test, in comparison to only 10% among controls (chi-square = 27.8, df = 1; P < 0.0001). Alterations of cell mediated immunity (multitest, LTT) were observed in 48.5% of patients, alterations of humoral immunity (Ig) in 31.8%, and alterations of markers of autoimmune disorders (autoantibodies, complement activation) in 37.9% of the cases. CONCLUSIONS: Our results support the hypothesis that there is some involvement of the immune system in the pathogenesis of Peyronie's disease, although the available data still appear to be insufficient to formulate a definite pathogenetic hypothesis. PMID- 9372890 TI - Urine levels of transforming growth factor-beta 1 in children with ureteropelvic junction obstruction. AB - OBJECTIVES: To determine if there are measurable quantities of transforming growth factor-beta 1 (TGF-beta 1) in the urine of children with either normal or pathologic conditions of the urinary tract, specifically vesicoureteral reflux (VUR) and ureteropelvic junction obstruction (UPJO). We also sought to determine if the urine TGF-beta level could distinguish between renal obstruction and no obstruction. METHODS: Preoperative bladder urine from consecutive patients undergoing pyeloplasty (UPJO group; n = 13), ureteral reimplantation (VUR group; n = 11), or circumcision/orchiopexy (control group; n = 19) as well as urine from the renal pelvis of the UPJO group was collected. The urine level of TGF-beta 1 was measured using a quantitative sandwich enzyme immunoassay technique. RESULTS: Urine level of TGF-beta 1 was detected in each group: control (26.6 +/- 6.3 pg/mL), reflux (22.1 +/- 9.6), UPJO-pelvic urine (82.4 +/- 19.3), UPJO-bladder urine (31.2 +/- 8.2). The urine TGF-beta 1 concentration in pelvic urine in the UPJO group was significantly higher than that in bladder urine in children in the UPJO group (p = 0.03). TGF-beta 1 concentrations were similar from the bladder of children in all three study groups (p = NS). CONCLUSIONS: Urine TGF-beta 1 is detectable in children with normal and pathologic urinary tracts. The level of this urine marker is elevated in the renal pelvis of children with UPJO compared to the level in the bladder of either obstructed or nonobstructed upper urinary tracts. PMID- 9372891 TI - Prepubertal varicoceles. AB - OBJECTIVES: Varicoceles are rarely detected in prepubertal boys. In an effort to further determine the natural history of prepubertal varicoceles, we have reviewed our experience with prepubertal boys who had varicoceles. METHODS: Eleven patients with prepubertal varicoceles were seen. The majority of patients (9 of 11) were asymptomatic. The mean age was 10.8 years (range 6 to 12). Ten of 11 patients had left-sided varicoceles. All varicoceles were grade III except for one that was grade II. Four patients underwent varicocele ligation, 3 via the Ivanessevich approach and 1 via the Palomo approach. RESULTS: The 4 patients who underwent varicocele ligation (operative group) had a follow-up that ranged from 6 to 72 months (mean 27.2) and the 7 patients who were observed (nonoperative group) had follow-up that ranged from 17 to 84 months (mean 40.8). All patients in the operative group exhibited "catch-up" growth of the affected testicle (mean relative testicular size 47% to 84% at follow-up). The relative left testicular size in the nonoperative group had decreased by a mean of 16.8% from the time of presentation (100% to 83.2% on follow-up). CONCLUSIONS: We conclude that prepubertal boys should be screened in the standing position for the presence of varicoceles. Secondary causes should be excluded. Patients may ultimately require intervention as our initial experience suggests improved testicular growth with early surgical repair. PMID- 9372892 TI - Fluorescence detection of bladder carcinoma. PMID- 9372893 TI - Benign pelvic mesothelioma. PMID- 9372894 TI - Spontaneous nontraumatic rupture of a contracted kidney with subcapsular and perirenal hematoma in a patient receiving chronic hemodialysis. AB - Spontaneous renal bleeding with diversion of blood into the subcapsular and/or perinephric spaces in a patient on chronic hemodialysis is a very rare clinical entity. We describe a patient on chronic hemodialysis in whom a spontaneous renal subcapsular hematoma and perirenal hemorrhage developed in a contracted kidney. PMID- 9372895 TI - Use of DHEA in a patient with advanced prostate cancer: a case report and review. AB - Dehydroepiandrosterone (DHEA) is being evaluated in the basic science laboratories as a potential treatment for adenocarcinomas, with some initial promise for success. However DHEA can be metabolically converted to androgenic compounds, possessing unwanted side effects. A patient with advanced prostate cancer with progressive symptomatology was treated with DHEA after other treatment regimens failed. Many of his symptoms improved on DHEA therapy, but his cancer also flared dramatically during treatment. His previous hormonally unresponsive cancer subsequently responded transiently to third-line hormonal therapy with diethylstilbestrol (DES). Adrenal precursor molecules such as DHEA may have significant therapeutic benefits in a number of diseases of the elderly, however their utility may be limited by potential androgenic side effects including endocrine epithelial cell growth. The development of analogue compounds with less conversion to androgenic metabolites should be considered, as molecules such as DHEA are more widely tested and utilized clinically. PMID- 9372896 TI - Eccrine sweat gland carcinoma of the scrotum with associated extramammary Paget's disease. AB - Sweat gland carcinomas are rare tumors which have not previously been reported as arising from the scrotum. We present the first known case of primary eccrine sweat gland carcinoma of the scrotum in association with extramammary Paget's disease (EPD) and review the presentation and management of these tumors. Sweat gland carcinomas frequently coexist with EPD and this association provides insight into the histogenesis of EPD, which is presently unknown. Sweat gland carcinoma should be included in the differential diagnosis of cutaneous scrotal tumors and carefully ruled out pathologically if the diagnosis of EPD alone is made. PMID- 9372897 TI - Transitional cell carcinoma of the fossa navicularis. AB - We report a case of transitional cell carcinoma of the fossa navicularis in an elderly white male. The patient presented in urinary retention, with a large exophytic mass at the external urethral meatus. Both the pathogenesis and natural history of this highly unusual tumor are unclear. Treatment depends on grade and stage of disease. Transurethral resection and fulguration have been successfully used to treat superficial lesions. Segmental resection and partial penectomy, with or without inguinal lymph node dissection, form the mainstay of treatment for invasive disease. The role of chemotherapy for advanced disease is unknown. PMID- 9372898 TI - Prolonged penile erection in the newborn. AB - An extensive review of the literature suggests that priapism or prolonged penile erection is extremely rare in the newborn. We present a term newborn whose clinical course of prolonged penile erection was a result of polycythemia. In the past, only 3 cases appear to have been associated with polycythemia. However, two of these cases had several other complicating factors. The remaining episodes have been described as idiopathic (7), or attributed to infection (1) or central nervous system insult (1). The recognition of this phenomenon and its historical record of clinical course is important in the newborn so inappropriate approaches to treatment may be avoided. Because of spontaneous detumescence in many instances, observation or nonsurgical management is advocated for the newborn with prolonged penile erection. PMID- 9372899 TI - Preliminary immunohistochemical characterization of a monoclonal antibody (PRO:4 216) prepared from human prostate cancer nuclear matrix proteins. AB - OBJECTIVES: A nuclear matrix protein (PC-1) was previously identified and reported to be present only in human prostate cancer but absent in tissue from the same prostate containing either benign prostatic hyperplasia (BPH) or normal prostate tissue. The PC-1 protein was identified by high resolution two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and exhibited a molecular mass of 56 kDa and an isoelectric point of 6.58. This work investigates the immunohistochemical characterization of PRO:4-216, a monoclonal antibody to PC-1. METHODS: Areas of the 2D-PAGE gels containing the human prostate cancer nuclear matrix proteins near PC-1 were isolated, eluted, and injected into mice to develop monoclonal antibodies. Antibodies were screened by immunofluorescence for nuclear reactivity to a human prostate cancer cell line (LnCaP) and by 1D and 2D Western blots for reactivity with prostate cancer nuclear matrix proteins. Monoclonal antibodies from the selected clones were affinity purified. The monoclonal antibody PRO:4-216 was used to analyze frozen tissue from 20 cancerous, 22 BPH, and 22 normal regions from fresh human prostate specimens. Tissue sections were analyzed for their immunohistochemical (IHC) (horseradish peroxidase) staining. RESULTS: Using a reference value for positive staining at an IHC score of greater than 50, 85% (17 of 20) of the cancerous, 5% (1 of 22) of the BPH, and 9% (2 of 22) of the normal prostate tissues stained positive. The one BPH and two normal tissues that stained positive were taken from prostates in which the adjacent cancerous tissue also demonstrated high IHC scores (greater than 225). CONCLUSIONS: These data demonstrate nuclear reactivity on fresh frozen human prostate cancer tissue for the monoclonal antibody PRO:4-216. PRO:4-216 may aid in distinguishing normal prostate and BPH from cancerous tissue. PMID- 9372900 TI - MUSE therapy: preliminary clinical observations. AB - OBJECTIVES: Intracavernosal injection of vasodilating agents has been a mainstay in the treatment of erectile dysfunction. Recently, a transurethral delivery system (MUSE) for alprostadil (prostaglandin E1) was introduced as an alternative form of pharmacotherapy. METHODS: One hundred consecutive patients with erectile dysfunction were treated with MUSE in doses ranging from 125 to 1000 micrograms and their erections were observed in the clinical setting. All patients had previous intracavernosal injections of combination pharmacotherapy (papavarine, Regitine, and/or prostaglandin E1). RESULTS: Of these 100 patients that used MUSE, only 7% had well-sustained, rigid erections while 30% had full erections but with partial rigidity. The remaining 63% of patients did not achieve erections that they thought were adequate for penetration. Penile and/or perineal pain occurred in 24% of patients, 3% had a syncopal episode, and 3% experienced urethral bleeding. One patient had priapism that required drainage. Using intracavernosal injections, 49% had sustained rigid erections, 40% had full erections with partial rigidity, and 11% did not have a response satisfactory for penetration. CONCLUSIONS: These data suggest that intracavernosal injections appear to be more effective than MUSE in achieving a rigid erection in men with erectile dysfunction. PMID- 9372901 TI - Renal microcirculatory effects of lovastatin in a rat model of reduced renal mass. AB - OBJECTIVES: Patients with reduced renal mass are at increased risk of developing renal failure. A remnant kidney model has been used to study the hemodynamic and structural changes that occur. We recently reported that the lipid-lowering agent lovastatin preserves renal function in this model. The purpose of the present study was to determine the specific effects of lovastation on the renal microcirculation of rats with reduced renal mass. METHODS: We used the rat hydronephrotic kidney preparation with a 5/6 partial nephrectomy. This model allows direct visualization of preglomerular and postglomerular vessels using videomicroscopy. The diameters and vascular responses to acetylcholine and angiotensin II of the interlobular, afferent, and efferent vessels were determined in two groups of animals with renal mass reduction: 15 rats with no lovastatin treatment and 18 rats treated with oral lovastatin (15 mg/kg body weight/day) for 2 weeks. RESULTS: In the lovastatin-treated rats, the baseline efferent vessel diameter was smaller by 21% (P < 0.05), but the interlobular and afferent vessel baseline diameters were not different from those in the untreated rats. Serum creatinine levels were lower in the treated rats (1.5 +/- 0.1 versus 2.0 +/- 0.2 mg/dL, P < 0.05), but serum lipids were not different. In the lovastatin-treated rats, vascular reactivity to acetylcholine was enhanced in the afferent and decreased in the efferent vessels. CONCLUSIONS: In this renal ablation model, lovastatin preserved renal function as measured by serum creatinine without lowering plasma lipid levels. Lovastatin treatment resulted in smaller efferent vessel diameters. Lovastatin also increased the vasodilatory response to acetylcholine in the afferent vessels. Together, these preglomerular and postglomerular changes would increase the single-nephron glomerular filtration rate. The renal protective effect of lovastatin may be due to these vasoactive effects on the renal microcirculation. PMID- 9372902 TI - Free ureteral replacement in rats: regeneration of ureteral wall components in the acellular matrix graft. AB - OBJECTIVES: To evaluate ureteral replacement by a free homologous graft of acellular matrix in a rat model. METHODS: In 30 male Sprague-Dawley rats, a 0.3 to 0.8-cm midsegment of the left ureter was resected and replaced with an acellular matrix graft of equal length placed on a polyethylene stent. The animals were killed at varying intervals, and the grafted specimens were prepared for light and electron microscopy. RESULTS: In all animals, the acellular matrix graft remained in its original position without evidence of incrustation or infection, and histologic examination showed complete epithelialization and progressive infiltration by vessels. At 10 weeks, smooth muscle fibers were observed; at 12 weeks, nerve fibers were first detected; at 4 months, smooth muscle cells had assumed regular configuration. CONCLUSIONS: The ureteral acellular matrix graft appears to promote the regeneration of all ureteral wall components. PMID- 9372903 TI - Testicular descent and ascent in the first year of life. PMID- 9372904 TI - Prostate cancer micrometastases to lymph nodes. PMID- 9372905 TI - Fulminant hepatic failure associated with bicalutamide. PMID- 9372906 TI - Laser prostatectomy versus electrovaporization of the prostate. PMID- 9372907 TI - Methionine and cysteine affect glutathione level, glutathione-related enzyme activities and the expression of glutathione S-transferase isozymes in rat hepatocytes. AB - Methionine and cysteine are constituents of glutathione. To understand the effects of these two sulfur amino acids on the glutathione (GSH)-dependent detoxification defense system, intracellular GSH and GSH-related enzyme activities, including GSH peroxidase, GSH reductase, GSH S-transferase (GST) and gamma-glutamylcysteine synthetase, were determined. In addition, the expression of three GST isozymes and carbonic anhydrase III (CA III) was examined. Hepatocytes isolated from male Sprague-Dawley rats were cultured with 0.1, 0.3, 0.5 or 1.0 mmol/L each of L-methionine and L-cysteine, for up to 7 d. Cells incubated with 0.5 or 1.0 mmol/L methionine and cysteine had increased intracellular GSH. A twofold increase was observed on d 6 compared with freshly isolated hepatocytes (P < 0.05). However, intracellular GSH was lower in cells treated with 0.3 or 0.1 mmol/L each of methionine and cysteine than in cells tested with 0.5 or 1.0 mmol/L. Although the GSH level differed significantly between cells cultured with 0.3 or 1.0 mmol/L of methionine and cysteine, GSH related enzymes did not differ at these two concentrations. The activity generally remained constant for the first 24 h, then increased up to d 4. Immunodetection analysis revealed no difference in the level of CA III and GST isoforms, Ya, Yb and Yp, with amino acids each at a concentration of at least 0.3 mmol/L. Yp expression steadily increased up to d 7. Most proteins decreased rapidly after 48 h when cultured with 0.1 mmol/L of methionine and cysteine; however, the Yp level increased up to d 6. In conclusion, results indicate that a twofold increase of intracellular GSH is reached by adding methionine and cysteine at a concentration >0.5 mmol/L to the culture medium. The concentrations of methionine and cysteine for maintaining hepatic GSH are higher than for GSH related enzyme activity and for GST isoform expression. PMID- 9372908 TI - The polycomb group protein complex of Drosophila melanogaster has different compositions at different target genes. AB - In Drosophila the Polycomb group genes are required for the long-term maintenance of the repressed state of many developmental regulatory genes. Their gene products are thought to function in a common multimeric complex that associates with Polycomb group response elements (PREs) in target genes and regulates higher order chromatin structure. We show that the chromodomain of Polycomb is necessary for protein-protein interactions within a Polycomb-Polyhomeotic complex. In addition, Posterior Sex Combs protein coimmunoprecipitates Polycomb and Polyhomeotic, indicating that they are members of a common multimeric protein complex. Immunoprecipitation experiments using in vivo cross-linked chromatin indicate that these three Polycomb group proteins are associated with identical regulatory elements of the selector gene engrailed in tissue culture cells. Polycomb, Polyhomeotic, and Posterior Sex Combs are, however, differentially distributed on regulatory sequences of the engrailed-related gene invected. This suggests that there may be multiple different Polycomb group protein complexes which function at different target sites. Furthermore, Polyhomeotic and Posterior Sex Combs are also associated with expressed genes. Polyhomeotic and Posterior Sex Combs may participate in a more general transcriptional mechanism that causes modulated gene repression, whereas the inclusion of Polycomb protein in the complex at PREs leads to stable silencing. PMID- 9372909 TI - Mutational analysis of the D1/E1 core helices and the conserved N-terminal region of yeast transcription factor IIB (TFIIB): identification of an N-terminal mutant that stabilizes TATA-binding protein-TFIIB-DNA complexes. AB - The general transcription factor IIB (TFIIB) plays an essential role in transcription of protein-coding genes by RNA polymerase II. We have used site directed mutagenesis to assess the role of conserved amino acids in several important regions of yeast TFIIB. These include residues in the highly conserved amino-terminal region and basic residues in the D1 and E1 core domain alpha helices. Acidic substitutions of residues K190 (D1) and K201 (E1) resulted in growth impairments in vivo, reduced basal transcriptional activity in vitro, and an inability to form stable TFIIB-TATA-binding protein-DNA (DB) complexes. Significantly, these mutants retained the ability to respond to acidic activators in vivo and to the Gal4-VP16 activator in vitro, supporting the view that these basic residues play a role in basal transcription. In addition, 14 single-amino acid substitutions were introduced in the conserved amino-terminal region. Three of these mutants, the L50D, R64E, and R78L mutants, displayed altered growth properties in vivo and were compromised for supporting transcription in vitro. The L50D mutant was impaired for RNA polymerase II interaction, while the R64E mutant exhibited altered transcription start site selection both in vitro and in vivo and, surprisingly, was more active than the wild type in the formation of stable DB complexes. These results support the view that the amino-terminal domain is involved in the direct interaction between yeast TFIIB and RNA polymerase II and suggest that this domain may interact with DNA and/or modulate the formation of a DB complex. PMID- 9372910 TI - Transcriptional activation by TFIIB mutants that are severely impaired in interaction with promoter DNA and acidic activation domains. AB - Biochemical experiments indicate that the general transcription factor IIB (TFIIB) can interact directly with acidic activation domains and that activators can stimulate transcription by increasing recruitment of TFIIB to promoters. For promoters at which recruitment of TFIIB to promoters is limiting in vivo, one would predict that transcriptional activity should be particularly sensitive to TFIIB mutations that decrease the association of TFIIB with promoter DNA and/or with activation domains; i.e., such TFIIB mutations should exacerbate a limiting step that occurs in wild-type cells. Here, we describe mutations on the DNA binding surface of TFIIB that severely affect both TATA-binding protein (TBP) TFIIB-TATA complex formation and interaction with the VP16 activation domain in vitro. These TFIIB mutations affect the stability of the TBP-TFIIB-TATA complex in vivo because they are synthetically lethal in combination with TBP mutants impaired for TFIIB binding. Interestingly, these TFIIB derivatives support viability, and they efficiently respond to Gal4-VP16 and natural acidic activators in different promoter contexts. These results suggest that in vivo, recruitment of TFIIB is not generally a limiting step for acidic activators. However, one TFIIB derivative shows reduced transcription of GAL4, suggesting that TFIIB may be limiting at a subset of promoters in vivo. PMID- 9372911 TI - Recruitment of the putative transcription-repair coupling factor CSB/ERCC6 to RNA polymerase II elongation complexes. AB - Cockayne's syndrome (CS) is a disease characterized by developmental and growth defects, sunlight sensitivity, and a defect in transcription-coupled nucleotide excision repair. The two principle proteins involved in CS, CSA and CSB/ERCC6, have been hypothesized to bind RNA polymerase II (Pol II) and link transcription to DNA repair. We have tested CSA and CSB in assays designed to determine their role in transcription-coupled repair. Using a unique oligo(dC)-tailed DNA template, we provide biochemical evidence that CSB/ERCC6 interacts with Pol II molecules engaged in ternary complexes containing DNA and nascent RNA. CSB is a DNA-activated ATPase, and hydrolysis of the ATP beta-gamma phosphoanhydride bond is required for the formation of a stable Pol II-CSB-DNA-RNA complex. Unlike CSB, CSA does not directly bind Pol II. PMID- 9372912 TI - Regulation of Id3 cell cycle function by Cdk-2-dependent phosphorylation. AB - The functions of basic helix-loop-helix (bHLH) transcription factors in activating differentiation-linked gene expression and in inducing G1 cell cycle arrest are negatively regulated by members of the Id family of HLH proteins. These bHLH antagonists are induced during a mitogenic signalling response, and they function by sequestering their bHLH targets in inactive heterodimers that are unable to bind to specific gene regulatory (E box) sequences. Recently, cyclin E-Cdk2- and cyclin A-Cdk2-dependent phosphorylation of a single conserved serine residue (Ser5) in Id2 has been shown to occur during late G1-to-S phase transition of the cell cycle, and this neutralizes the function of Id2 in abrogating E-box-dependent bHLH homo- or heterodimer complex formation in vitro (E. Hara, M. Hall, and G. Peters, EMBO J. 16:332-342, 1997). We now show that an analogous cell-cycle-regulated phosphorylation of Id3 alters the specificity of Id3 for abrogating both E-box-dependent bHLH homo- or heterodimer complex formation in vitro and E-box-dependent reporter gene function in vivo. Furthermore, compared with wild-type Id3, an Id3 Asp5 mutant (mimicking phosphorylation) is unable to promote cell cycle S phase entry in transfected fibroblasts, whereas an Id3 Ala5 mutant (ablating phosphorylation) displays an activity significantly greater than that of wild-type Id3 protein. Cdk2-dependent phosphorylation therefore provides a switch during late G1-to-S phase that both nullifies an early G1 cell cycle regulatory function of Id3 and modulates its target bHLH specificity. These data also demonstrate that the ability of Id3 to promote cell cycle S phase entry is not simply a function of its ability to modulate bHLH heterodimer-dependent gene expression and establish a biologically important mechanism through which Cdk2 and Id-bHLH functions are integrated in the coordination of cell proliferation and differentiation. PMID- 9372913 TI - Initiation of DNA interstrand cross-link repair in humans: the nucleotide excision repair system makes dual incisions 5' to the cross-linked base and removes a 22- to 28-nucleotide-long damage-free strand. AB - Most DNA repair mechanisms rely on the redundant information inherent to the duplex to remove damaged nucleotides and replace them with normal ones, using the complementary strand as a template. Interstrand cross-links pose a unique challenge to the DNA repair machinery because both strands are damaged. To study the repair of interstrand cross-links by mammalian cells, we tested the activities of cell extracts of wild-type or excision repair-defective rodent cell lines and of purified human excision nuclease on a duplex with a site-specific cross-link. We found that in contrast to monoadducts, which are removed by dual incisions bracketing the lesion, the cross-link causes dual incisions, both 5' to the cross-link in one of the two strands. The net result is the generation of a 22- to 28-nucleotide-long gap immediately 5' to the cross-link. This gap may act as a recombinogenic signal to initiate cross-link removal. PMID- 9372914 TI - A disease-associated G5703A mutation in human mitochondrial DNA causes a conformational change and a marked decrease in steady-state levels of mitochondrial tRNA(Asn). AB - We introduced mitochondrial DNA (mtDNA) from a patient with a mitochondrial myopathy into established mtDNA-less human osteosarcoma cells. The resulting transmitochondrial cybrid lines, containing either exclusively wild-type or mutated (G5703A transition in the tRNA[Asn] gene) mtDNA, were characterized and analyzed for oxidative phosphorylation function and steady-state levels of different RNA species. Functional studies showed that the G5703A mutation severely impairs oxidative phosphorylation function and mitochondrial protein synthesis. We detected a marked reduction in tRNA(Asn) steady-state levels which was not associated with an accumulation of intermediate transcripts containing tRNA(Asn) sequences or decreased transcription. Native polyacrylamide gel electrophoresis showed that the residual tRNA(Asn) fraction in mutant cybrids had an altered conformation, suggesting that the mutation destabilized the tRNA(Asn) secondary or tertiary structure. Our results suggest that the G5703 mutation causes a conformational change in the tRNA(Asn) which may impair aminoacylation. This alteration leads to a severe reduction in the functional tRNA(Asn) pool by increasing its in vivo degradation by mitochondrial RNases. PMID- 9372915 TI - Hepatitis B virus X protein induces RNA polymerase III-dependent gene transcription and increases cellular TATA-binding protein by activating the Ras signaling pathway. AB - Our previous studies have shown that the hepatitis B virus protein, X, activates all three classes of RNA polymerase III (pol III)-dependent promoters by increasing the cellular level of TATA-binding protein (TBP) (H.-D. Wang et al., Mol. Cell. Biol. 15:6720-6728, 1995), a limiting transcription component (A. Trivedi et al., Mol. Cell. Biol. 16:6909-6916, 1996). We have investigated whether these X-mediated events are dependent on the activation of the Ras/Raf-1 signaling pathway. Transient expression of a dominant-negative mutant Ras gene (Ras-ala15) in a Drosophila S-2 stable cell line expressing X (X-S2), or incubation of the cells with a Ras farnesylation inhibitor, specifically blocked both the X-dependent activation of a cotransfected tRNA gene and the increase in cellular TBP levels. Transient expression of a constitutively activated form of Ras (Ras-val12) in control S2 cells produced both an increase in tRNA gene transcription and an increase in cellular TBP levels. These events are not cell type specific since X-mediated gene induction was also shown to be dependent on Ras activation in a stable rat 1A cell line expressing X. Furthermore, increases in RNA pol III-dependent gene activity and TBP levels could be restored in X-S2 cells expressing Ras-ala15 by coexpressing a constitutively activated form of Raf 1. These events are serum dependent, and when the cells are serum deprived, the X mediated effects are augmented. Together, these results demonstrate that the X mediated induction of RNA pol III-dependent genes and increase in TBP are both dependent on the activation of the Ras/Raf-1 signaling cascade. In addition, these studies define two new and important consequences mediated by the activation of the Ras signal transduction pathway: an increase in the central transcription factor, TBP, and the induction of RNA pol III-dependent gene activity. PMID- 9372916 TI - Vac7p, a novel vacuolar protein, is required for normal vacuole inheritance and morphology. AB - During cell division, the vacuole of Saccharomyces cerevisiae partitions between mother and daughter cells. A portion of the parental vacuole membrane moves into the bud, and ultimately membrane scission divides the vacuole into two separate structures. Here we characterize two yeast mutations causing defects in vacuole membrane scission, vac7-1 and vac14-1. A third mutant, afab1-2 strain, isolated in a nonrelated screen (A. Yamamoto et al., Mol. Biol. Cell 6:525-539, 1995) shares the vacuolar phenotypes of the vac7-1 and vac14-1 strains. Unlike the wild type, mutant vacuoles are not multilobed structures; in many cases, a single vacuole spans both the mother and bud, with a distinct gap in the mother-bud neck. Thus, even where the membranes are closely opposed, vacuole fission is arrested. Simply enlarging the vacuole does not produce this mutant phenotype. An additional common phenotype of these mutants is a defect in vacuole acidification; however, vacuole scission in most other vacuole acidification mutants is normal. An alteration in vacuole membrane lipids could account for both the vacuole membrane scission and acidification defects. Because a directed screen has not identified additional class III complementation groups, it is likely that all three genes are involved in a similar process. Interestingly, FAB1, was previously shown to encode a putative phosphatidylinositol-4-phosphate 5-kinase. Moreover, overexpression of FAB1 suppresses the vac14-1 mutation, which suggests that VAC14 and FAB1 act at a common step. VAC7 encodes a novel 128-kDa protein that is localized at the vacuole membrane. This location of Vac7p is consistent with its involvement in vacuole morphology and inheritance. PMID- 9372917 TI - Transmembrane glycoprotein gp150 is a substrate for receptor tyrosine phosphatase DPTP10D in Drosophila cells. AB - We have begun to explore the downstream signaling pathways of receptor protein tyrosine phosphatases (RPTPs) that control axon guidance decisions in the Drosophila central nervous system. We have focused our studies on the adhesion molecule-like gp150 protein, which binds directly to and is an in vitro substrate for the RPTP DPTP10D. Here we show that gp150 and DPTP10D form stable complexes in Drosophila Schneider 2 (S2) cells and in wild-type larval tissue. We also demonstrate that the DPTP10D cytoplasmic domain is sufficient to confer binding to gp150. gp150 has a short cytoplasmic domain containing four tyrosines, all found within sequences similar to immunoreceptor family tyrosine-based activation motifs (ITAMs). We demonstrate that gp150 is tyrosine phosphorylated in wild-type larvae. In S2 cells, gp150 becomes tyrosine phosphorylated following incubation with PTP inhibitors or upon coexpression of the Dsrc tyrosine kinase. Phosphorylated Dsrc and an unknown 40-kDa phosphoprotein form stable complexes with gp150, thereby implicating them in a putative gp150 signaling pathway. When coexpressed with gp150, either full-length DPTP10D or its cytoplasmic domain mediates gp150 dephosphorylation whereas a catalytically inactive DPTP10D cytoplasmic domain does not. The neural RPTP DPTP99A can also induce gp150 dephosphorylation but does not coimmunoprecipitate with gp150. Taken together, the results suggest that gp150 transduces signals via phosphorylation of its ITAM like elements. Phosphotyrosines on gp150 might function as binding sites for downstream signaling molecules, thereby initiating a signaling cascade that could be modulated in vivo by RPTPs such as DPTP10D. PMID- 9372919 TI - Binding of eukaryotic translation initiation factor 4E (eIF4E) to eIF4G represses translation of uncapped mRNA. AB - mRNA translation in crude extracts from the yeast Saccharomyces cerevisiae is stimulated by the cap structure and the poly(A) tail through the binding of the cap-binding protein eukaryotic translation initiation factor 4E (eIF4E) and the poly(A) tail-binding protein Pab1p. These proteins also bind to the translation initiation factor eIF4G and thereby link the mRNA to the general translational apparatus. In contrast, uncapped, poly(A)-deficient mRNA is translated poorly in yeast extracts, in part because of the absence of eIF4E and Pab1p binding sites on the mRNA. Here, we report that uncapped-mRNA translation is also repressed in yeast extracts due to the binding of eIF4E to eIF4G. Specifically, we find that mutations which weaken the eIF4E binding site on the yeast eIF4G proteins Tif4631p and Tif4632p lead to temperature-sensitive growth in vivo and the stimulation of uncapped-mRNA translation in vitro. A mutation in eIF4E which disturbs its ability to interact with eIF4G also leads to a stimulation of uncapped-mRNA translation in vitro. Finally, overexpression of eIF4E in vivo or the addition of excess eIF4E in vitro reverses these effects of the mutations. These data support the hypothesis that the eIF4G protein can efficiently stimulate translation of exogenous uncapped mRNA in extracts but is prevented from doing so as a result of its association with eIF4E. They also suggest that some mRNAs may be translationally regulated in vivo in response to the amount of free eIF4G in the cell. PMID- 9372918 TI - Role of Schizosaccharomyces pombe RecQ homolog, recombination, and checkpoint genes in UV damage tolerance. AB - The cellular responses to DNA damage are complex and include direct DNA repair pathways that remove the damage and indirect damage responses which allow cells to survive DNA damage that has not been, or cannot be, removed. We have identified the gene mutated in the rad12.502 strain as a Schizosaccharomyces pombe recQ homolog. The same gene (designated rqh1) is also mutated in the hus2.22 mutant. We show that Rqhl is involved in a DNA damage survival mechanism which prevents cell death when UV-induced DNA damage cannot be removed. This pathway also requires the correct functioning of the recombination machinery and the six checkpoint rad gene products plus the Cdsl kinase. Our data suggest that Rqh1 operates during S phase as part of a mechanism which prevents DNA damage causing cell lethality. This process may involve the bypass of DNA damage sites by the replication fork. Finally, in contrast with the reported literature, we do not find that rqh1 (rad12) mutant cells are defective in UV dimer endonuclease activity. PMID- 9372920 TI - Differential recognition of liganded and unliganded thyroid hormone receptor by retinoid X receptor regulates transcriptional repression. AB - Thyroid hormone receptor (TR) functions as part of multiprotein complexes that also include retinoid X receptor (RXR) and transcriptional coregulators. We have found that both the TR CoR box and ninth heptad are required for RXR interaction and in turn for interaction with corepressor proteins N-CoR and SMRT. Remarkably, the recruitment of RXR to repression-defective CoR box and ninth-heptad mutants via a heterologous dimerization interface restores both corepressor interaction and repression. The addition of thyroid hormone obviates the CoR box requirement for RXR interaction, provided that the AF2 activation helix at the C terminus of TR is intact. These results indicate that RXR differentially recognizes the unliganded and liganded conformations of TR and that these differences appear to play a major role in the recruitment of corepressors to TR-RXR heterodimers. PMID- 9372921 TI - Promoter activity of Tat at steps subsequent to TATA-binding protein recruitment. AB - Artificial recruitment of TATA-binding protein (TBP) to many eukaryotic promoters bypasses DNA-bound activator function. The human immunodeficiency virus type 1 (HIV-1) Tat is an unconventional activator that up-regulates transcription from the HIV-1 long terminal repeat (LTR) through binding to a nascent RNA sequence, TAR. Because this LTR and its cognate activator have atypical features compared to a standard RNA polymerase II (RNAP II) transcriptional unit, the precise limiting steps for HIV-1 transcription and how Tat resolves these limitations remain incompletely understood. We thus constructed human TBP fused to the DNA binding domain of GAL4 to determine whether recruitment of TBP is one rate limiting step in HIV-1 LTR transcription and whether Tat functions to recruit TBP. As a control, we compared the activity of the adenovirus E1b promoter. Our findings indicate that TBP tethering to the E1b promoter fully effected transcription to the same degree achievable with the potent GAL4-VP16 activator. By contrast, TBP recruitment to the HIV-1 LTR, although necessary for conferring Tat responsiveness, did not bypass a physical need for Tat in achieving activated transcription. These results document that the HIV-1 and the E1b promoters are transcriptionally limited at different steps; the major rate-limiting step for E1b is recruitment of TBP, while activation of the HIV-1 LTR requires steps in addition to TBP recruitment. We suggest that Tat acts to accelerate rate-limiting steps after TBP recruitment. PMID- 9372923 TI - Identification and characterization of XPC-binding domain of hHR23B. AB - hHR23B was originally isolated as a component of a protein complex that specifically complements nucleotide excision repair (NER) defects of xeroderma pigmentosum group C cell extracts in vitro and was identified as one of two human homologs of the Saccharomyces cerevisiae NER gene product Rad23. Recombinant hHR23B has previously been shown to significantly stimulate the NER activity of recombinant human XPC protein (rhXPC). In this study we identify and functionally characterize the XPC-binding domain of hHR23B protein. We prepared various internal as well as terminal deletion products of hHR23B protein in a His-tagged form and examined their binding with rhXPC by using nickel-chelating Sepharose. We demonstrate that a domain covering 56 amino acids of hHR23B is required for binding to rhXPC as well as for stimulation of in vitro NER reactions. Interestingly, a small polypeptide corresponding to the XPC-binding domain is sufficient to exert stimulation of XPC NER activity. Comparison with known crystal structures and analysis with secondary structure programs provided strong indications that the binding domain has a predominantly amphipathic alpha-helical character, consistent with evidence that the affinity with XPC is based on hydrophobic interactions. Our work shows that binding to XPC alone is required and sufficient for the role of hHR23B in in vitro NER but does not rule out the possibility that the protein has additional functions in vivo. PMID- 9372922 TI - Inhibition of cell spreading by expression of the C-terminal domain of focal adhesion kinase (FAK) is rescued by coexpression of Src or catalytically inactive FAK: a role for paxillin tyrosine phosphorylation. AB - pp125FAK is a tyrosine kinase that appears to regulate the assembly of focal adhesions and thereby promotes cell spreading on the extracellular matrix. In some cells, the C terminus of pp125FAK is expressed as a separate protein, pp41/43FRNK. We have previously shown that overexpression of pp41/43FRNK inhibits tyrosine phosphorylation of pp125FAK and paxillin and, in addition, delays cell spreading and focal adhesion assembly. Thus, pp41/43FRNK functions as a negative inhibitor of adhesion signaling and provides a tool to dissect the mechanism by which pp125FAK promotes cell spreading. We report here that the inhibitory effects of pp41/43FRNK expression can be rescued by the co-overexpression of wild type pp125FAK and partially rescued by catalytically inactive variants of pp125FAK. However, coexpression of an autophosphorylation site mutant of pp125FAK, which fails to bind the SH2 domain of pp60c-Src, or a mutant that fails to bind paxillin did not promote cell spreading. In contrast, expression of pp41/43FRNK and pp60c-Src reconstituted cell spreading and tyrosine phosphorylation of paxillin but did so without inducing tyrosine phosphorylation of pp125FAK. These data provide additional support for a model whereby pp125FAK acts as a "switchable adaptor" that recruits pp60c-Src to phosphorylate paxillin, promoting cell spreading. In addition, these data point to tyrosine phosphorylation of paxillin as being a critical step in focal adhesion assembly. PMID- 9372924 TI - Two human homologs of Rad23 are functionally interchangeable in complex formation and stimulation of XPC repair activity. AB - XPC-hHR23B protein complex is specifically involved in nucleotide excision repair (NER) of DNA lesions on transcriptionally inactive sequences as well as the nontranscribed strand of active genes. Here we demonstrate that not only highly purified recombinant hHR23B (rhHR23B) but also a second human homolog of the Saccharomyces cerevisiae Rad23 repair protein, hHR23A, stimulates the in vitro repair activity of recombinant human XPC (rhXPC), revealing functional redundancy between these human Rad23 homologs. Coprecipitation experiments with His-tagged rhHR23 as well as sedimentation velocity analysis showed that both rhHR23 proteins in vitro reconstitute a physical complex with rhXPC. Both complexes were more active than free rhXPC, indicating that complex assembly is required for the stimulation. rhHR23B was shown to stimulate an early stage of NER at or prior to incision. Furthermore, both rhHR23 proteins function in a defined NER system reconstituted with purified proteins, indicating direct involvement of hHR23 proteins in the DNA repair reaction via interaction with XPC. PMID- 9372925 TI - RAG-1 and RAG-2-dependent assembly of functional complexes with V(D)J recombination substrates in solution. AB - V(D)J recombination is initiated by RAG-1 and RAG-2, which introduce double strand DNA breaks at recombination signal sequences (RSSs) of antigen receptor gene segments to produce signal ends, terminating in blunt, double-strand breaks, and coding ends, terminating in DNA hairpins. While the formation of RAG-RSS complexes has been documented, observations regarding the individual contributions of RAG-1 and RAG-2 to RSS recognition are in conflict. Here we describe an assay for formation and maintenance of functional RAG-RSS complexes in the course of the DNA cleavage reaction. Under conditions of in vitro cleavage, the RAG proteins sequester intact substrate DNA in a stable complex which is formed prior to strand scission. The cleavage reaction subsequently proceeds through nicking and hairpin formation without dissociation of substrate. Notably, the presence of both RAG-1 and RAG-2 is essential for formation of stable, functional complexes with substrate DNA under conditions of the sequestration assay. Two classes of substrate mutation are distinguished by their effects on RAG-mediated DNA cleavage in vitro. A mutation of the first class, residing within the RSS nonamer and associated with coordinate impairment of nicking and hairpin formation, greatly reduces the stability of RAG association with intact substrate DNA. In contrast, a mutation of the second class, lying within the RSS heptamer and associated with selective abolition of hairpin formation, has little or no effect on the half-life of the RAG-substrate complex. PMID- 9372926 TI - Human eukaryotic translation initiation factor 4G (eIF4G) possesses two separate and independent binding sites for eIF4A. AB - Mammalian translation initiation factor 4F (eIF4F) consists of three subunits, eIF4A, eIF4E, and eIF4G. eIF4G interacts directly with both eIF4A and eIF4E. The binding site for eIF4E is contained in the amino-terminal third of eIF4G, while the binding site for eIF4A was mapped to the carboxy-terminal third of the molecule. Here we show that human eIF4G possesses two separate eIF4A binding domains in the middle third (amino acids [aa] 478 to 883) and carboxy-terminal third (aa 884 to 1404) of the molecule. The amino acid sequence of the middle portion of eIF4G is well conserved between yeasts and humans. We show that mutations of conserved amino acid stretches in the middle domain abolish or reduce eIF4A binding as well as eIF3 binding. In addition, a separate and nonoverlapping eIF4A binding domain exists in the carboxy-terminal third (aa 1045 to 1404) of eIF4G, which is not present in yeast. The C-terminal two-thirds region (aa 457 to 1404) of eIF4G, containing both eIF4A binding sites, is required for stimulating translation. Neither one of the eIF4A binding domains alone activates translation. In contrast to eIF4G, human p97, a translation inhibitor with homology to eIF4G, binds eIF4A only through the amino-terminal proximal region, which is homologous to the middle domain of eIF4G. PMID- 9372927 TI - A heterologous maize rpoB editing site is recognized by transgenic tobacco chloroplasts. AB - Single nucleotides in plant chloroplast transcripts are edited from the genomically encoded C to U, often resulting in changes of the encoded protein sequence. Site-specific trans-acting factors are postulated to direct the selection of edited residues. In order to further define cis sequences required for RNA editing, we investigated whether two editing sites present in maize rpoB mRNA would be recognized by the editing machinery of transformed tobacco chloroplasts. A 93-nucleotide (nt) segment surrounding site I is sufficient to direct editing of the maize sequence in tobacco chloroplasts. However, an 86-nt segment surrounding maize site IV (which is genomically encoded as a T in tobacco) does not confer editing of this site, suggesting that trans-acting factors necessary for recognition of site IV are not present in tobacco. The maize sequences surrounding site I were found to compete with the endogenous rpoB for a depletable trans factor and to reduce editing of endogenous site I. The presence of exogenous maize site I was also found to decrease editing of endogenous tobacco site II, indicating that there is a shared aspect of editing for some closely spaced editing sites. PMID- 9372928 TI - Sin mutations of histone H3: influence on nucleosome core structure and function. AB - Sin mutations in Saccharomyces cerevisiae alleviate transcriptional defects that result from the inactivation of the yeast SWVI/SNF complex. We have investigated the structural and functional consequences for the nucleosome of Sin mutations in histone H3. We directly test the hypothesis that mutations in histone H3 leading to a SWI/SNF-independent (Sin) phenotype in yeast lead to nucleosomal destabilization. In certain instances this is shown to be true; however, nucleosomal destabilization does not always occur. Topoisomerase I-mediated relaxation of minichromosomes assembled with either mutant histone H3 or wild type H3 together with histones H2A, H2B, and H4 indicates that DNA is constrained into nucleosomal structures containing either mutant or wild-type proteins. However, nucleosomes containing particular mutant H3 molecules (R116-H and T118 I) are more accessible to digestion by micrococcal nuclease and do not constrain DNA in a precise rotational position, as revealed by digestion with DNase I. This result establishes that Sin mutations in histone H3 located close to the dyad axis can destabilize histone-DNA contacts at the periphery of the nucleosome core. Other nucleosomes containing a distinct mutant H3 molecule (E105-K) associated with a Sin phenotype show very little change in nucleosome structure and stability compared to wild-type nucleosomes. Both mutant and wild-type nucleosomes continue to restrict the binding of either TATA-binding protein/transcription factor IIA (TFIIA) or the RNA polymerase III transcription machinery. Thus, different Sin mutations in histone H3 alter the stability of histone-DNA interactions to various extents in the nucleosome while maintaining the fundamental architecture of the nucleosome and contributing to a common Sin phenotype. PMID- 9372929 TI - Tumor necrosis factor alpha and interleukin-1beta regulate the murine manganese superoxide dismutase gene through a complex intronic enhancer involving C/EBP beta and NF-kappaB. AB - Manganese superoxide dismutase (MnSOD), a tumor necrosis factor (TNF)-inducible reactive oxygen-scavenging enzyme, protects cells from TNF-mediated apoptosis. To understand how MnSOD is regulated, transient transfections of promoter-reporter gene constructions, in vitro DNA binding assays, and in vivo genomic footprint (IVGF) analysis were carried out on the murine MnSOD gene. The results of this analysis identified a 238-bp region of intron 2 that was responsive to TNF and interleukin-1beta (IL-1). This TNF response element (TNFRE) had the properties of a traditional enhancer element that functioned in an orientation- and position independent manner. IVGF of the TNFRE revealed TNF- and IL-1-induced factor occupancy of sites that could bind NF-kappaB and C/EBP. The 5' portion of the TNFRE bound C/EBP-beta in vitro and was both necessary and sufficient for TNF responsiveness with the MnSOD promoter or with a heterologous promoter when in an upstream position. The 3' end of the TNFRE bound both NF-kappaB and C/EBP but was not necessary for TNF responsiveness with the MnSOD promoter. However, this 3' portion of the TNFRE was required for the TNFRE to function as a downstream enhancer with a heterologous promoter. These data functionally separate the MnSOD TNFRE into a region responsible for TNF activation and one that mediates induction when it is downstream of a promoter. PMID- 9372930 TI - Yap, a novel family of eight bZIP proteins in Saccharomyces cerevisiae with distinct biological functions. AB - Saccharomyces cerevisiae contains eight members of a novel and fungus-specific family of bZIP proteins that is defined by four atypical residues on the DNA binding surface. Two of these proteins, Yap1 and Yap2, are transcriptional activators involved in pleiotropic drug resistance. Although initially described as AP-1 factors, at least four Yap proteins bind most efficiently to TTACTAA, a sequence that differs at position +/-2 from the optimal AP-1 site (TGACTCA); further, a Yap-like derivative of the AP-1 factor Gcn4 (A239Q S242F) binds efficiently to the Yap recognition sequence. Molecular modeling suggests that the Yap-specific residues make novel contacts and cause physical constraints at the +/-2 position that may account for the distinct DNA-binding specificities of Yap and AP-1 proteins. To various extents, Yap1, Yap2, Yap3, and Yap5 activate transcription from a promoter containing a Yap recognition site. Yap-dependent transcription is abolished in strains containing high levels of protein kinase A; in contrast, Gcn4 transcriptional activity is stimulated by protein kinase A. Interestingly, Yap1 transcriptional activity is stimulated by hydrogen peroxide, whereas Yap2 activity is stimulated by aminotriazole and cadmium. In addition, unlike other yap mutations tested, yap4 (cin5) mutations affect chromosome stability, and they suppress the cold-sensitive phenotype of yap1 mutant strains. Thus, members of the Yap family carry out overlapping but distinct biological functions. PMID- 9372932 TI - The Saccharomyces cerevisiae Hap5p homolog from fission yeast reveals two conserved domains that are essential for assembly of heterotetrameric CCAAT binding factor. AB - The CCAAT-binding factor is an evolutionarily conserved heteromeric transcription factor that binds to CCAAT box-containing upstream activation sites within the promoters of numerous eukaryotic genes. The CCAAT-binding factor from Saccharomyces cerevisiae is a heterotetramer that contains the subunits Hap2p, Hap3p, Hap4p, and Hap5p and that functions in the activation of genes involved in respiratory metabolism. Here we describe the isolation of the cDNA encoding the Schizosaccharomyces pombe homolog of Hap5p, designated php5+. We have shown that Php5p is a subunit of the CCAAT-binding factor in fission yeast and is required for transcription of the S. pombe cyc1+ gene. Analysis of the evolutionarily conserved regions of Hap5p, Php5p, and the mammalian homolog CBF-C revealed two essential domains within Hap5p that are required for DNA binding and transcriptional activation. One is an 87-amino-acid core domain that is conserved among Hap5p, Php5p, and CBF-C and that is required for the assembly of the Hap2p Hap3p-Hap5p heterotrimer both in vitro and in vivo. A second domain that is essential for the recruitment of Hap4p into the CCAAT-binding complex was identified in Hap5p and Php5p. PMID- 9372931 TI - Subunit composition determines E2F DNA-binding site specificity. AB - The product of the retinoblastoma (Rb) susceptibility gene, Rb-1, regulates the activity of a wide variety of transcription factors, such as E2F, in a cell cycle dependent fashion. E2F is a heterodimeric transcription factor composed of two subunits each encoded by one of two related gene families, denoted E2F and DP. Five E2F genes, E2F-1 through E2F-5, and two DP genes, DP-1 and DP-2, have been isolated from mammals, and heterodimeric complexes of these proteins are expressed in most, if not all, vertebrate cells. It is not yet clear whether E2F/DP complexes regulate overlapping and/or specific cellular genes. Moreover, little is known about whether Rb regulates all or a subset of E2F-dependent genes. Using recombinant E2F, DP, and Rb proteins prepared in baculovirus infected cells and a repetitive immunoprecipitation-PCR procedure (CASTing), we have identified consensus DNA-binding sites for E2F-1/DP-1, E2F-1/DP-2, E2F-4/DP 1, and E2F-4/DP-2 complexes as well as an Rb/E2F-1/DP-1 trimeric complex. Our data indicate that (i) E2F, DP, and Rb proteins each influence the selection of E2F-binding sites; (ii) E2F sites differ with respect to their intrinsic DNA bending properties; (iii) E2F/DP complexes induce distinct degrees of DNA bending; and (iv) complex-specific E2F sites selected in vitro function distinctly as regulators of cell cycle-dependent transcription in vivo. These data indicate that the specific sequence of an E2F site may determine its role in transcriptional regulation and suggest that Rb/E2F complexes may regulate subsets of E2F-dependent cellular genes. PMID- 9372933 TI - Tumor suppressor Smad4 is a transforming growth factor beta-inducible DNA binding protein. AB - Members of the Smad family of proteins are thought to play important roles in transforming growth factor beta (TGF-beta)-mediated signal transduction. In response to TGF-beta, specific Smads become inducibly phosphorylated, form heteromers with Smad4, and undergo nuclear accumulation. In addition, overexpression of specific Smad combinations can mimic the transcriptional effect of TGF-beta on both the plasminogen activator inhibitor 1 (PAI-1) promoter and the reporter construct p3TP-Lux. Although these data suggest a role for Smads in regulating transcription, the precise nuclear function of these heteromeric Smad complexes remains largely unknown. Here we show that in Mv1Lu cells Smad3 and Smad4 form a TGF-beta-induced, phosphorylation-dependent, DNA binding complex that specifically recognizes a bipartite binding site within p3TP-Lux. Furthermore, we demonstrate that Smad4 itself is a DNA binding protein which recognizes the same sequence. Interestingly, mutations which eliminate the Smad DNA binding site do not interfere with either TGF-beta-dependent transcriptional activation or activation by Smad3/Smad4 cooverexpression. In contrast, mutation of adjacent AP1 sites within this context eliminates both TGF-beta-dependent transcriptional activation and activation in response to Smad3/Smad4 cooverexpression. Furthermore, concatemerized AP1 sites, in isolation, are activated by Smad3/Smad4 cooverexpression and, to a certain extent, by TGF-beta. Taken together, these data suggest that the Smad3/Smad4 complex has at least two separable nuclear functions: it forms a rapid, yet transient sequence-specific DNA binding complex, and it potentiates AP1-dependent transcriptional activation. PMID- 9372935 TI - Bad is a BH3 domain-containing protein that forms an inactivating dimer with Bcl XL. AB - The Bcl-2 related protein Bad is a promoter of apoptosis and has been shown to dimerize with the anti-apoptotic proteins Bcl-2 and Bcl-XL. Overexpression of Bad in murine FL5.12 cells demonstrated that the protein not only could abrogate the protective capacity of coexpressed Bcl-XL but could accelerate the apoptotic response to a death signal when it was expressed in the absence of exogenous Bcl XL. Using deletion analysis, we have identified the minimal domain in the murine Bad protein that can dimerize with Bcl-xL. A 26-amino-acid peptide within this domain, which showed significant homology to the alpha-helical BH3 domains of related apoptotic proteins like Bak and Bax, was found to be necessary and sufficient to bind Bcl-xL. To determine the role of dimerization in regulating the death-promoting activity of Bad and the death-inhibiting activity of Bcl-xL, mutations within the hydrophobic BH3-binding pocket in Bcl-xL that eliminated the ability of Bcl-xL to form a heterodimer with Bad were tested for the ability to promote cell survival in the presence of Bad. Several of these mutants retained the ability to impart protection against cell death regardless of the level of coexpressed Bad protein. These results suggest that BH3-containing proteins like Bad promote cell death by binding to antiapoptotic members of the Bcl-2 family and thus inhibiting their survival promoting functions. PMID- 9372934 TI - SSP1, a gene necessary for proper completion of meiotic divisions and spore formation in Saccharomyces cerevisiae. AB - During meiosis, a diploid cell undergoes two rounds of nuclear division following one round of DNA replication to produce four haploid gametes. In yeast, haploid meiotic products are packaged into spores. To gain new insights into meiotic development and spore formation, we followed differential expression of genes in meiotic versus vegetatively growing cells in the yeast Saccharomyces cerevisiae. Our results indicate that there are at least five different classes of transcripts representing genes expressed at different stages of the sporulation program. Here we describe one of these differentially expressed genes, SSP1, which plays an essential role in meiosis and spore formation. SSP1 is expressed midway through meiosis, and homozygous ssp1 diploid cells fail to sporulate. In the ssp1 mutant, meiotic recombination is normal but viability declines rapidly. Both meiotic divisions occur at the normal time; however, the fraction of cells completing meiosis is significantly reduced, and nuclei become fragmented soon after meiosis II. The ssp1 defect does not appear to be related to a microtubule cytoskeletal-dependent event and is independent of two rounds of chromosome segregation. The data suggest that Ssp1 is likely to function in a pathway that controls meiotic nuclear divisions and coordinates meiosis and spore formation. PMID- 9372936 TI - Npp106p, a Schizosaccharomyces pombe nucleoporin similar to Saccharomyces cerevisiae Nic96p, functionally interacts with Rae1p in mRNA export. AB - To identify components of the mRNA export machinery in Schizosaccharomyces pombe, a screen was developed to identify mutations that were synthetically lethal with the conditional mRNA export allele rae1-167. Mutations defining three complementation groups were isolated, and here we report the characterization of npp106 (for nuclear pore protein of 106 kDa). This gene encodes a predicted protein that has significant similarity to the Nic96p nucleoporin of Saccharomyces cerevisiae. Consistent with Npp106p being a nucleoporin, a functional green fluorescent protein (GFP)-tagged Npp106p localized to the nuclear periphery. In contrast to NIC96, the npp106 gene is not essential. Moreover, a delta npp106 mutant did not show cytoplasmic mislocalization of a simian virus 40 nuclear localization signal-GFP-LacZ reporter protein, and a fraction of cells had accumulation of poly(A)+ RNA in the nucleus. A consequence of the synthetic lethality between rae1-167 and npp106-1 was the accumulation of poly(A)+ RNA in the nucleus when cells were grown under synthetic lethal conditions. In addition to npp106-1, which is a nonsense mutation that truncates the protein at amino acid 292, the delta npp106 mutation was synthetically lethal with rae1-167, suggesting that the synthetic lethality is a consequence of the loss of a function of npp106. We further demonstrate that a region between amino acids 74 and 348 of Npp106p is required for complementation of the synthetic lethality. These results uncover a potential direct or indirect involvement of Npp106p in mRNA export. PMID- 9372937 TI - The yeast silent information regulator Sir4p anchors and partitions plasmids. AB - Circular plasmids containing telomeric TG1-3 arrays or the HMR E silencer segregate efficiently between dividing cells of the yeast Saccharomyces cerevisiae. Subtelomeric X repeats augment the TG1-3 partitioning activity by a process that requires the SIR2, SIR3, and SIR4 genes, which are also required for silencer-based partitioning. Here we show that targeting Sir4p to DNA directly via fusion to the bacterial repressor LexA confers efficient mitotic segregation to otherwise unstable plasmids. The Sir4p partitioning activity resides within a 300-amino-acid region (residues 950 to 1262) which precedes the coiled-coil dimerization motif at the extreme carboxy end of the protein. Using a topology based assay, we demonstrate that the partitioning domain also retards the axial rotation of LexA operators in vivo. The anchoring and partitioning properties of LexA-Sir4p chimeras persist despite the loss of the endogenous SIR genes, indicating that these functions are intrinsic to Sir4p and not to a complex of Sir factors. In contrast, inactivation of the Sir4p-interacting protein Rap1p reduces partitioning by a LexA-Sir4p fusion. The data are consistent with a model in which the partitioning and anchoring domain of Sir4p (PAD4 domain) attaches to a nuclear component that divides symmetrically between cells at mitosis; DNA linked to Sir4p by LexA serves as a reporter of protein movement in these experiments. We infer that the segregation behavior of telomere- and silencer based plasmids is, in part, a consequence of these Sir4p-mediated interactions. The assays presented herein illustrate two novel approaches to monitor the intracellular dynamics of nuclear proteins. PMID- 9372938 TI - Base pair conformation-dependent excision of benzo[a]pyrene diol epoxide-guanine adducts by human nucleotide excision repair enzymes. AB - Human nucleotide excision repair processes carcinogen-DNA adducts at highly variable rates, even at adjacent sites along individual genes. Here, we identify conformational determinants of fast or slow repair by testing excision of N2 guanine adducts formed by benzo[a]pyrene diol epoxide (BPDE), a potent and ubiquitous mutagen that induces mainly G x C-->T x A transversions and frameshift deletions. We found that human nucleotide excision repair processes the predominant (+)-trans-BPDE-N2-dG adduct 15 times less efficiently than a standard acetylaminofluorene-C8-dG lesion in the same sequence. No difference was observed between (+)-trans- and (-)-trans-BPDE-N2-dG, but excision was enhanced about 10 fold by changing the adduct configurations to either (+)-cis- or (-)-cis-BPDE-N2 dG. Conversely, excision of (+)-cis- and (-)-cis- but not (+)-trans-BPDE-N2-dG was reduced about 10-fold when the complementary cytosine was replaced by adenine, and excision of these BPDE lesions was essentially abolished when the complementary deoxyribonucleotide was missing. Thus, a set of chemically identical BPDE adducts yielded a greater-than-100-fold range of repair rates, demonstrating that nucleotide excision repair activity is entirely dictated by local DNA conformation. In particular, this unique comparison between structurally highly defined substrates shows that fast excision of BPDE-N2-dG lesions is correlated with displacement of both the modified guanine and its partner base in the complementary strand from their normal intrahelical positions. The very slow excision of carcinogen-DNA adducts located opposite deletion sites reveals a cellular strategy that minimizes the fixation of frameshifts after mutagenic translesion synthesis. PMID- 9372939 TI - DNA in transcriptionally silent chromatin assumes a distinct topology that is sensitive to cell cycle progression. AB - Transcriptionally silent regions of the Saccharomyces cerevisiae genome, the silent mating type loci and telomeres, represent the yeast equivalent of metazoan heterochromatin. To gain insight into the nature of silenced chromatin structure, we have examined the topology of DNA spanning the HML silent mating type locus by determining the superhelical density of mini-circles excised from HML (HML circles) by site-specific recombination. We observed that HML circles excised in a wild-type (SIR+) strain were more negatively supercoiled upon deproteinization than were the same circles excised in a sir- strain, in which silencing was abolished, even when HML alleles in which neither circle was transcriptionally competent were used. cis-acting sites flanking HML, called silencers, are required in the chromosome for establishment and inheritance of silencing. HML circles excised without silencers from cells arrested at any point in the cell cycle retained SIR-dependent differences in superhelical density. However, progression through the cell cycle converted SIR+ HML circles to a form resembling that of circles from sir- cells. This decay was not observed with circles carrying a silencer. These results establish that (i) DNA in transcriptionally silenced chromatin assumes a distinct topology reflecting a distinct organization of silenced versus active chromatin; (ii) the altered chromatin structure in silenced regions likely results from changes in packaging of individual nucleosomes, rather than changes in nucleosome density; and (iii) cell cycle progression disrupts the silenced chromatin structure, a process that is counteracted by silencers. PMID- 9372940 TI - Nucleolar KKE/D repeat proteins Nop56p and Nop58p interact with Nop1p and are required for ribosome biogenesis. AB - Different point mutations in the nucleolar protein fibrillarin (Nop1p in Saccharomyces cerevisiae) can inhibit different steps in ribosome synthesis. A screen for mutations that are synthetically lethal (sl) with the nop1-5 allele, which inhibits pre-rRNA processing, identified NOP56. An independent sl mutation screen with nop1-3, which inhibits pre-rRNA methylation, identified a mutation in NOP58. Strikingly, Nop56p and Nop58p are highly homologous (45% identity). Both proteins were found to be essential and localized to the nucleolus. A temperature sensitive lethal mutant allele, nop56-2, inhibited many steps in pre-rRNA processing, particularly on the pathway of 25S/5.8S rRNA synthesis, and led to defects in 60S subunit assembly. Epitope-tagged constructs show that both Nop56p and Nop58p are associated with Noplp in complexes, Nop56p and Nop1p exhibiting a stoichiometric association. These physical interactions presumably underlie the observed sl phenotypes. Well-conserved homologs are present in a range of organisms, including humans (52% identity between human hNop56p and yeast Nop56p), suggesting that these complexes have been conserved in evolution. PMID- 9372941 TI - U1 small nuclear RNA-promoted exon selection requires a minimal distance between the position of U1 binding and the 3' splice site across the exon. AB - Both experimental work and surveys of the lengths of internal exons in nature have suggested that vertebrate internal exons require a minimum size of approximately 50 nucleotides for efficient inclusion in mature mRNA. This phenomenon has been ascribed to steric interference between complexes involved in recognition of the splicing signals at the two ends of short internal exons. To determine whether U1 small nuclear ribonucleoprotein, a multicomponent splicing factor that is involved in the first recognition of splice sites, contributes to the lower size limit of vertebrate internal exons, we have taken advantage of our previous observation that U1 small nuclear RNAs (snRNAs) which bind upstream or downstream of the 5' splice site (5'SS) stimulate splicing of the upstream intron. By varying the position of U1 binding relative to the 3'SS, we show that U1-dependent splicing of the upstream intron becomes inefficient when U1 is positioned 48 nucleotides or less downstream of the 3'SS, suggesting a minimal distance between U1 and the 3'SS of approximately 50 nucleotides. This distance corresponds well to the suggested minimum size of internal exons. The results of experiments in which the 3'SS region of the reporter was duplicated suggest an optimal distance of greater than 72 nucleotides. We have also found that inclusion of a 24-nucleotide miniexon is promoted by the binding of U1 to the downstream intron but not by binding to the 5'SS. Our results are discussed in the context of models to explain constitutive splicing of small exons in nature. PMID- 9372942 TI - Concerted activity of host cell factor subregions in promoting stable VP16 complex assembly and preventing interference by the acidic activation domain. AB - In contrast to our understanding of the roles of Oct-1 and VP16 in VP16-mediated transcriptional activation, virtually nothing is known of the role of the second cellular component, termed host cell factor (HCF), or of its structure-function relationships. We show that the majority of the internal region of HCF, including the repeats involved in HCF cleavage, is dispensable for complex assembly with VP16 and Oct-1. The N-terminal domain of HCF (HCF.N) had only weak VP16 binding and complex promoting activity, while the C-terminal region (HCF.C) had no intrinsic activity. However, the C-terminal region strongly enhanced complex formation and reduced dissociation kinetics when linked to the N-terminal domain (HCF.NC). The potent activity of the HCF.NC fusion in complex assembly was recapitulated in vivo in yeast and mammalian cells. Moreover, HCF.N could promote increased complex formation when the acidic activation domain of VP16 was deleted. Restoration of the activation domain strongly inhibited complex formation with HCF.N, but the addition of the C-terminal domain of HCF restored strong stable complex formation with intact VP16. The results indicate that this C-terminal domain is critically required to alter the presentation of the acidic domain of VP16. Additional results are consistent with the interpretation that this alteration in acidic domain presentation for complex assembly also facilitates the activation function in VP16. The sequence of an HCF homolog from Caenorhabditis elegans shows it to be a natural HCF.NC construct, reinforcing the conclusions from our functional analysis. PMID- 9372943 TI - A tetratricopeptide repeat mutation in yeast transcription factor IIIC131 (TFIIIC131) facilitates recruitment of TFIIB-related factor TFIIIB70. AB - Transcription factor IIIC (TFIIIC) plays an important role in assembling the initiation factor TFIIIB on genes transcribed by RNA polymerase III (Pol III). In Saccharomyces cerevisiae, assembly of the TFIIIB complex by promoter-bound TFIIIC is thought to be initiated by its tetratricopeptide repeat (TPR)-containing subunit, TFIIIC131, which interacts directly with the TFIIB-related factor, TFIIIB70/Brf1. In this work, we have identified 10 dominant mutations in TFIIIC131 that increase Pol III gene transcription. All of these mutations are found within a discrete 53-amino-acid region of the protein encompassing TPR2. Biochemical studies of one of the mutations (PCF1-2) show that the increase in transcription is due to an increase in the recruitment of TFIIIB70 to TFIIC-DNA. The PCF1-2 mutation does not affect the affinity of TFIIIC for DNA, and the differential in both transcription and TFIIIB complex assembly is observed at saturating levels of TFIIIB70. This indicates that mutant and wild-type TFIIIC DNA complexes have the same affinity for TFIIIB70 and suggests that the increased recruitment of this factor is achieved by a nonequilibrium binding mechanism. A novel mechanism of activation in which the TPR mutations facilitate a conformational change in TFIIIC that is required for TFIIIB70 binding is proposed. The implications of this model for the regulation of processes involving TPR proteins are discussed. PMID- 9372944 TI - Novel receptor interaction and repression domains in the orphan receptor SHP. AB - SHP (short heterodimer partner) is a novel orphan receptor that lacks a conventional DNA binding domain and interacts with other members of the nuclear hormone receptor superfamily. We have characterized the SHP sequences required for interaction with other superfamily members, and have defined an SHP repressor domain. In the mammalian two-hybrid system, a fusion of full-length SHP to the GAL4 DNA binding domain shows 9-cis-retinoic acid-dependent interaction with a VP16-retinoid X receptor alpha (RXR alpha) fusion. By deletion analysis, sequences required for this RXR interaction map to the central portion of SHP (amino acids 92 to 148). The same region is required for interaction with RXR in vitro and in the yeast two-hybrid system, and results from the yeast system suggest that the same SHP sequences are required for interaction with other members of the nuclear hormone receptor superfamily such as thyroid hormone receptor and retinoic acid receptor. In mammalian cells, a GAL4-SHP fusion protein shows about 10-fold-decreased transcriptional activation relative to GAL4 alone, and fusion of SHP to the C terminus of a GAL4-VP16 fusion to generate a triple chimera also results in a strong decrease in transactivation activity. Sequences required for this repressor function were mapped to the C terminus of SHP. This region is distinct from that required for corepressor interaction by other members of the nuclear hormone receptor superfamily, and SHP did not interact with N-CoR in either the yeast or mammalian two-hybrid system. Together, these results identify novel receptor interaction and repressor domains in SHP and suggest two distinct mechanisms for inhibition of receptor signaling pathways by SHP. PMID- 9372945 TI - The Ras-specific exchange factors mouse Sos1 (mSos1) and mSos2 are regulated differently: mSos2 contains ubiquitination signals absent in mSos1. AB - We have compared aspects of the mouse sos1 (msos1) and msos2 genes, which encode widely expressed, closely related Ras-specific exchange factors. Although an msos1 plasmid did not induce phenotypic changes in NIH 3T3 cells, addition of a 15-codon myristoylation signal to its 5' end enabled the resulting plasmid, myr sos1, to induce approximately one-half as many foci of transformed cells as a v-H ras control. By contrast, an isogenic myr-sos2 plasmid, which was made by fusing the first 102 codons from myr-sos1 at homologous sequences to an intact msos2 cDNA, did not induce focal transformation directly, although it could form foci in cooperation with c-H-ras. Pulse-chase experiments indicated that the half-life of Sos1 in NIH 3T3 cells was greater than 18 h, while that of Sos2 was less than 3 h. While in vitro-translated Sos1 was stable in a rabbit reticulocyte lysate, Sos2 was degraded in the lysate, as were each of two reciprocal chimeric Sos1 Sos2 proteins, albeit at a slower rate. In the lysate, Sos2 and the two chimeric proteins could be stabilized by ATPgammaS. Unlike Sos1, Sos2 was specifically immunoprecipitated by antiubiquitin antibodies. In a myristoylated version, the chimeric gene encoding Sos2 at its C terminus made a stable protein in NIH 3T3 cells and induced focal transformation almost as efficiently as myr-msos1, while the myristoylated protein encoded by the other chimera was unstable and defective in the transformation assay. We conclude that mSos2 is much less stable than mSos1 and is degraded by a ubiquitin-dependent process. A second mSos2 degradation signal, mapped to the C terminus in the reticulocyte lysate, does not seem to function under the growth conditions of the NIH 3T3 cells. PMID- 9372946 TI - A histone octamer blocks branch migration of a Holliday junction. AB - The Holliday junction is a key intermediate in genetic recombination. Here, we examine the effect of a nucleosome core on movement of the Holliday junction in vitro by spontaneous branch migration. Histone octamers consisting of H2A, H2B, H3, and H4 are reconstituted onto DNA duplexes containing an artificial nucleosome-positioning sequence consisting of a tandem array of an alternating AT GC sequence motif. Characterization of the reconstituted branch migration substrates by micrococcal nuclease mapping and exonuclease III and hydroxyl radical footprinting reveal that 70% of the reconstituted octamers are positioned near the center of the substrate and the remaining 30% are located at the distal end, although in both cases some translational degeneracy is observed. Branch migration assays with the octamer-containing substrates reveal that the Holliday junction cannot migrate spontaneously through DNA organized into a nucleosomal core unless DNA-histone interactions are completely disrupted. Similar results are obtained with branch migration substrates containing an octamer positioned on a naturally occurring sequence derived from the yeast GLN3 locus. Digestion of Holliday junctions with T7 endonuclease I establishes that the junction is not trapped by the octamer but can branch migrate in regions free of histone octamers. Our findings suggest that migration of Holliday junctions during recombination and the recombinational repair of DNA damage requires proteins not only to accelerate the intrinsic rate of branch migration but also to facilitate the passage of the Holliday junction through a nucleosome. PMID- 9372947 TI - Elevated recombination in immortal human cells is mediated by HsRAD51 recombinase. AB - Normal diploid cells have a limited replicative potential in culture, with progressively increasing interdivision time. Rarely, cell lines arise which can divide indefinitely; like tumor cells, such "immortal" lines display frequent chromosomal aberrations which may reflect high rates of recombination. Recombination frequencies within a plasmid substrate were 3.5-fold higher in nine immortal human cell lines than in six untransformed cell strains. Expression of HsRAD51, a human homolog of the yeast RAD51 and Escherichia coli recA recombinase genes, was 4.5-fold higher in immortal cell lines than in mortal cells. Stable transformation of human fibroblasts with simian virus 40 large T antigen prior to cell immortalization increased both chromosomal recombination and the level of HsRAD51 transcripts by two- to fivefold. T-antigen induction of recombination was efficiently blocked by introduction of HsRAD51 antisense (but not control) oligonucleotides spanning the initiation codon, implying that HsRAD51 expression mediates augmented recombination. Since p53 binds and inactivates HsRAD51, T antigen-p53 association may block such inactivation and liberate HsRAD51. Upregulation of HsRAD51 transcripts in T-antigen-transformed and other immortal cells suggests that recombinase activation can also occur at the RNA level and may facilitate cell transformation to immortality. PMID- 9372948 TI - Architecture of the yeast origin recognition complex bound to origins of DNA replication. AB - In many organisms, the replication of DNA requires the binding of a protein called the initiator to DNA sites referred to as origins of replication. Analyses of multiple initiator proteins bound to their cognate origins have provided important insights into the mechanism by which DNA replication is initiated. To extend this level of analysis to the study of eukaryotic chromosomal replication, we have investigated the architecture of the Saccharomyces cerevisiae origin recognition complex (ORC) bound to yeast origins of replication. Determination of DNA residues important for ORC-origin association indicated that ORC interacts preferentially with one strand of the ARS1 origin of replication. DNA binding assays using ORC complexes lacking one of the six subunits demonstrated that the DNA binding domain of ORC requires the coordinate action of five of the six ORC subunits. Protein-DNA cross-linking studies suggested that recognition of origin sequences is mediated primarily by two different groups of ORC subunits that make sequence-specific contacts with two distinct regions of the DNA. Implications of these findings for ORC function and the mechanism of initiation of eukaryotic DNA replication are discussed. PMID- 9372950 TI - 3' processing of human pre-U2 small nuclear RNA: a base-pairing interaction between the 3' extension of the precursor and an internal region. AB - The spliceosomal small nuclear RNAs U1, U2, U4, and U5 are transcribed by RNA polymerase II as precursors with extensions at their 3' ends. The 3' processing of these pre-snRNAs is not understood in detail. Two pathways of pre-U2 RNA 3' processing in vitro were revealed in the present investigation by using a series of human wild-type and mutant pre-U2 RNAs. Substrates with wild-type 3' ends were initially shortened by three or four nucleotides (which is the first step in vivo), and the correct mature 3' end was then rapidly generated. In contrast, certain mutant pre-U2 RNAs displayed an aberrant 3' processing pathway typified by the persistence of intermediates representing cleavage at each internucleoside bond in the precursor 3' extension. Comparison of the wild-type and mutant pre-U2 RNAs revealed a potential base-pairing interaction between nucleotides in the precursor 3' extension and a sequence located between the Sm domain and stem-loop III of U2 RNA. Substrate processing competition experiments using a highly purified pre-U2 RNA 3' processing activity suggested that only RNAs capable of this base-pairing interaction had high affinity for the pre-U2 RNA 3' processing enzyme. The importance of this postulated base-pairing interaction between the precursor 3' extension and the internal region between the Sm domain and stem loop III was confirmed by the results obtained with a compensatory substitution that restores the base pairing, which displayed the normal 3' processing reaction. These results implicate a precursor-specific base-paired structure involving sequences on both sides of the mature cleavage site in the 3' processing of human U2 RNA. PMID- 9372949 TI - The amino terminus of the F1-ATPase beta-subunit precursor functions as an intramolecular chaperone to facilitate mitochondrial protein import. AB - Mitochondrial import signals have been shown to function in many steps of mitochondrial protein import. Previous studies have shown that the F1-ATPase beta subunit precursor (pre-F1beta) of the yeast Saccharomyces cerevisiae contains an extended, functionally redundant mitochondrial import signal at its amino terminus. However, the full significance of this functionally redundant targeting sequence has not been determined. We now report that the extended pre-F1beta signal acts to maintain the precursor in an import-competent conformation prior to import, in addition to its previously characterized roles in mitochondrial targeting and translocation. We found that this extended signal is required for the efficient posttranslational mitochondrial import of pre-F1beta both in vivo and in vitro. To determine whether the pre-F1beta signal directly influences precursor conformation, fusion proteins that contain wild-type and mutant forms of the pre-F1beta import signal attached to the model passenger protein dihydrofolate reductase (DHFR) were constructed. Deletions that reduced the import signal to a minimal functional unit decreased both the half-time of precursor folding and the efficiency of mitochondrial import. To confirm that the reduced mitochondrial import associated with this truncated signal was due to a defect in its ability to maintain DHFR in a loosely folded conformation, we introduced structurally destabilizing missense mutations into the DHFR passenger to block precursor folding independently of the import signal. We found that the truncated signal imported this destabilized form of DHFR as efficiently as the intact targeting signal, indicating that the primary defect associated with the minimal signal is an inability to maintain the precursor in a loosely folded conformation. Our results suggest that the loss of this intramolecular chaperone function leads to defects in the early stages of the import process. PMID- 9372951 TI - POU domain transcription factor brain 4 confers pancreatic alpha-cell-specific expression of the proglucagon gene through interaction with a novel proximal promoter G1 element. AB - The proglucagon gene is expressed in a highly restricted tissue-specific manner in the alpha cells of the pancreatic islet, the hypothalamus, and the small and large intestines. Proglucagon is processed to glucagon and glucagon-like peptides GLP-1 and -2. Glucagon is expressed in alpha cells and regulates glucose homeostasis. GLP-1 is implicated in the control of insulin secretion, food intake, and satiety signaling, and GLP-2 is implicated in regulating small-bowel growth. Cell-specific expression of the proglucagon gene is mediated by proteins that interact with the proximal G1 promoter element which contains several AT rich domains with binding sites for homeodomain transcription factors. In an attempt to identify major homeodomain proteins involved in pancreatic alpha-cell specific proglucagon expression, we found that the POU domain transcription factor brain 4 is abundantly expressed in proglucagon-producing islet cell lines and rat pancreatic islets. In the latter, brain 4 and glucagon immunoreactivity colocalize in the outer mantle of islets. Electrophoretic mobility shift assays with specific antisera identify brain 4 as a major constituent of nuclear proteins of glucagon-producing cells that bind to the G1 element of the proglucagon gene proximal promoter. Transcriptional transactivation experiments reveal that brain 4 is a major regulator of proglucagon gene expression by its interaction with the G1 element. The finding that a neuronal transcription factor is involved in glucagon gene transcription may explain the presence of proglucagon in certain areas of the brain as well as in pancreatic alpha cells. Further, this finding supports the idea that the neuronal properties of endodermis-derived endocrine pancreatic cells may find their basis in regulation of gene expression by neuronal transcription factors. PMID- 9372952 TI - Constitutive activation of gene expression by thyroid hormone receptor results from reversal of p53-mediated repression. AB - Thyroid hormone receptor (T3R) is a member of the steroid hormone receptor gene family of nuclear hormone receptors. In most cells T3R activates gene expression only in the presence of its ligand, L-triiodothyronine (T3). However, in certain cell types (e.g., GH4C1 cells) expression of T3R leads to hormone-independent constitutive activation. This activation by unliganded T3R occurs with a variety of gene promoters and appears to be independent of the binding of T3R to specific thyroid hormone response elements (TREs). Previous studies indicate that this constitutive activation results from the titration of an inhibitor of transcription. Since the tumor suppresser p53 is capable of repressing a wide variety of gene promoters, we considered the possibility that the inhibitor is p53. Evidence to support this comes from studies indicating that expression of p53 blocks T3R-mediated constitutive activation in GH4C1 cells. In contrast with hormone-independent activation by T3R, p53 had little or no effect on T3 dependent stimulation which requires TREs. In addition, p53 mutants which oligomerize with wild-type p53 and interfere with its function also increase promoter activity. This enhancement is of similar magnitude to but is not additive with the stimulation mediated by unliganded T3R, suggesting that they target the same factor. Since p53 mutants are known to target wild-type p53 in the cell, this suggests that T3R also interacts with p53 in vivo and that endogenous levels of p53 act to suppress promoter activity. Evidence supporting both functional and physical interactions of T3R and p53 in the cell is presented. The DNA binding domain (DBD) of T3R is important in mediating constitutive activation, and the receptor DBD appears to functionally interact with the N terminus of p53 in the cell. In vitro binding studies indicate that the T3R DBD is important for interaction of T3R with p53 and that this interaction is reduced by T3. These findings are consistent with the in vivo studies indicating that p53 blocks constitutive activation but not ligand dependent stimulation. These studies provide insight into mechanisms by which unliganded nuclear hormone receptors can modulate gene expression and may provide an explanation for the mechanism of action of the v-erbA oncoprotein, a retroviral homolog of chicken T3R alpha. PMID- 9372953 TI - Functional interaction of a novel cellular protein with the papillomavirus E2 transactivation domain. AB - The transactivation domain (AD) of bovine papillomavirus type 1 E2 stimulates gene expression and DNA replication. To identify cellular proteins that interact with this 215-amino-acid domain, we used a transactivation-defective mutant as bait in the yeast two-hybrid screen. In vitro and in vivo results demonstrate that the cDNA of one plasmid isolated in this screen encodes a 37-kDa nuclear protein that specifically binds to an 82-amino-acid segment within the E2 AD. Mutants with point mutations within this E2 domain were isolated based on their inability to interact with AMF-1 and were found to be unable to stimulate transcription. These mutants also exhibited defects in viral DNA replication yet retained binding to the viral E1 replication initiator protein. Overexpression of AMF-1 stimulated transactivation by both wild-type E2 and a LexA fusion to the E2 AD, indicating that AMF-1 is a positive effector of the AD of E2. We conclude that interaction with AMF-1 is necessary for the transcriptional activation function of the E2 AD in mammalian cells. PMID- 9372954 TI - p53 is phosphorylated by CDK7-cyclin H in a p36MAT1-dependent manner. AB - The tumor suppressor protein p53 acts as a transcriptional activator that can mediate cellular responses to DNA damage by inducing apoptosis and cell cycle arrest. p53 is a nuclear phosphoprotein, and phosphorylation has been proposed to be a means by which the activity of p53 is regulated. The cyclin-dependent kinase (CDK)-activating kinase (CAK) was originally identified as a cellular kinase required for the activation of a CDK-cyclin complex, and CAK is comprised of three subunits: CDK7, cyclin H, and p36MAT1. CAK is part of the transcription factor IIH multiprotein complex, which is required for RNA polymerase II transcription and nucleotide excision repair. Because of the similarities between p53 and CAK in their involvement in the cell cycle, transcription, and repair, we investigated whether p53 could act as a substrate for phosphorylation by CAK. While CDK7-cyclin H is sufficient for phosphorylation of CDK2, we show that p36MAT1 is required for efficient phosphorylation of p53 by CDK7-cyclin H, suggesting that p36MAT1 can act as a substrate specificity-determining factor for CDK7-cyclin H. We have mapped a major site of phosphorylation by CAK to Ser-33 of p53 and have demonstrated as well that p53 is phosphorylated at this site in vivo. Both wild-type and tumor-derived mutant p53 proteins are efficiently phosphorylated by CAK. Furthermore, we show that p36 and p53 can interact both in vitro and in vivo. These studies reveal a potential mechanism for coupling the regulation of p53 with DNA repair and the basal transcriptional machinery. PMID- 9372955 TI - Interaction of yeast repressor-activator protein Ume6p with glycogen synthase kinase 3 homolog Rim11p. AB - Meiosis and expression of early meiotic genes in the budding yeast Saccharomyces cerevisiae depend upon Rim11p, Ume6p, and Ime1p. Rim11p (also called Mds1p and ScGSK3) is a protein kinase related to glycogen synthase kinase 3 (GSK3); Ume6p is an architectural transcription factor; and Imelp is a Ume6p-binding protein that provides a transcriptional activation domain. Rim11p is required for Ime1p Ume6p interaction, and prior studies have shown that Rim11p binds to and phosphorylates Ime1p. We show here that Rim11p binds to and phosphorylates Ume6p, as well. Amino acid substitutions in Ume6p that alter a consensus GSK3 site reduce or abolish Rim11p-Ume6p interaction and Rim11p-dependent phosphorylation, and they cause defects in interaction between Ume6p and Ime1p and in meiotic gene expression. Therefore, interaction between Rim11p and Ume6p, resulting in phosphorylation of Ume6p, is required for Ime1p-Ume6p complex formation. Rim11p, like metazoan GSK3beta, phosphorylates both interacting subunits of a target protein complex. PMID- 9372956 TI - Regulatory sequences for the amplification and replication of the ribosomal DNA minichromosome in Tetrahymena thermophila. AB - We have analyzed the cis-acting sequences that regulate rRNA gene (rDNA) replication in Tetrahymena thermophila. The macronucleus of this ciliated protozoan contains 9,000 copies of a 21-kbp minichromosome in the form of a palindrome comprising two copies of the rDNA. These are derived from a single chromosomally integrated copy during conjugation through selective amplification and are maintained by replicating once per cell cycle during vegetative growth. We have developed a transformation vector and carried out a deletion analysis to determine the minimal sequences required for replication, amplification, and/or stable maintenance of the rDNA molecule. Using constructs containing progressively longer deletions, we show that only a small portion (approximately 900 bp) of the rDNA is needed for extrachromosomal replication and stable maintenance of this molecule. This core region is very near but does not include the rRNA transcription initiation site or its putative promoter, indicating that replication is not dependent on normal rRNA transcription. It includes two nearly identical nuclease-sensitive domains (D1 and D2), one of which (D1) corresponds to the physical origin of replication determined previously. Deletion of both domains abolishes replication, whereas deletion of either domain allows the molecules to replicate, indicating that only one domain is required. In addition to this core region, we have found several DNA segments, including a tandem array of a 21-nucleotide repeat (type II repeats) and sequences within the rRNA coding region, that play distinctive and important roles in maintaining the rDNA at a high copy number. PMID- 9372957 TI - A role for cyclin D3 in the endomitotic cell cycle. AB - Platelets, essential for thrombosis and hemostasis, develop from polyploid megakaryocytes which undergo endomitosis. During this cell cycle, cells experience abrogated mitosis and reenter a phase of DNA synthesis, thus leading to endomitosis. In the search for regulators of the endomitotic cell cycle, we have identified cyclin D3 as an important regulatory factor. Of the D-type cyclins, cyclin D3 is present at high levels in megakaryocytes undergoing endomitosis and is markedly upregulated following exposure to the proliferation-, maturation-, and ploidy-promoting factor, Mpl ligand. Transgenic mice in which cyclin D3 is overexpressed in the platelet lineage display a striking increase in endomitosis, similar to changes seen following Mpl ligand administration to normal mice. Electron microscopy analysis revealed that unlike such treated mice, however, D3 transgenic mice show a poor development of demarcation membranes, from which platelets are believed to fragment, and no increase in platelets. Thus, while our model supports a key role for cyclin D3 in the endomitotic cell cycle, it also points to the unique role of Mpl ligand in priming megakaryocytes towards platelet fragmentation. The role of cyclin D3 in promoting endomitosis in other lineages programmed to abrogate mitosis will need further exploration. PMID- 9372958 TI - Mutations in the hrp48 gene, which encodes a Drosophila heterogeneous nuclear ribonucleoprotein particle protein, cause lethality and developmental defects and affect P-element third-intron splicing in vivo. AB - The Drosophila melanogaster hnRNP protein, hrp48, is an abundant heterogeneous nuclear RNA-associated protein. Previous biochemical studies have implicated hrp48 as a component of a ribonucleoprotein complex involved in the regulation of the tissue-specific alternative splicing of the P-element third intron (IVS3). We have taken a genetic approach to analyzing the role of hrp48. Mutations in the hrp48 gene were identified and characterized. hrp48 is an essential gene. Hypomorphic mutations which reduce the level of hrp48 protein display developmental defects, including reduced numbers of ommatidia in the eye and morphological bristle abnormalities. Using a P-element third-intron reporter transgene, we found that reduced levels of hrp48 partially relieve IVS3 splicing inhibition in somatic cells. This is the first direct evidence that hrp48 plays a functional role in IVS3 splicing inhibition. PMID- 9372959 TI - E2F activity is regulated by cell cycle-dependent changes in subcellular localization. AB - E2F directs the cell cycle-dependent expression of genes that induce or regulate the cell division process. In mammalian cells, this transcriptional activity arises from the combined properties of multiple E2F-DP heterodimers. In this study, we show that the transcriptional potential of individual E2F species is dependent upon their nuclear localization. This is a constitutive property of E2F 1, -2, and -3, whereas the nuclear localization of E2F-4 is dependent upon its association with other nuclear factors. We previously showed that E2F-4 accounts for the majority of endogenous E2F species. We now show that the subcellular localization of E2F-4 is regulated in a cell cycle-dependent manner that results in the differential compartmentalization of the various E2F complexes. Consequently, in cycling cells, the majority of the p107-E2F, p130-E2F, and free E2F complexes remain in the cytoplasm. In contrast, almost all of the nuclear E2F activity is generated by pRB-E2F. This complex is present at high levels during G1 but disappears once the cells have passed the restriction point. Surprisingly, dissociation of this complex causes little increase in the levels of nuclear free E2F activity. This observation suggests that the repressive properties of the pRB E2F complex play a critical role in establishing the temporal regulation of E2F responsive genes. How the differential subcellular localization of pRB, p107, and p130 contributes to their different biological properties is also discussed. PMID- 9372960 TI - Fal1p is an essential DEAD-box protein involved in 40S-ribosomal-subunit biogenesis in Saccharomyces cerevisiae. AB - A previously uncharacterized Saccharomyces cerevisiae gene, FAL1, was found by sequence comparison as a homolog of the eukaryotic translation initiation factor 4A (eIF4A). Fal1p has 55% identity and 73% similarity on the amino acid level to yeast eIF4A, the prototype of ATP-dependent RNA helicases of the DEAD-box protein family. Although clearly grouped in the eIF4A subfamily, the essential Fal1p displays a different subcellular function and localization. An HA epitope-tagged Fal1p is localized predominantly in the nucleolus. Polysome analyses in a temperature-sensitive fal1-1 mutant and a Fal1p-depleted strain reveal a decrease in the number of 40S ribosomal subunits. Furthermore, these strains are hypersensitive to the aminoglycoside antibiotics paromomycin and neomycin. Pulse chase labeling of pre-rRNA and steady-state-level analysis of pre-rRNAs and mature rRNAs by Northern hybridization and primer extension in the Fal1p-depleted strain show that Fal1p is required for pre-rRNA processing at sites A0, A1, and A2. Consequently, depletion of Fal1p leads to decreased 18S rRNA levels and to an overall deficit in 40S ribosomal subunits. Together, these results implicate Fal1p in the 18S rRNA maturation pathway rather than in translation initiation. PMID- 9372961 TI - OCA-B is a functional analog of VP16 but targets a separate surface of the Oct-1 POU domain. AB - OCA-B is a B-cell-specific coregulator of the broadly expressed POU domain transcription factor Oct-1. OCA-B associates with the Oct-1 POU domain, a bipartite DNA-binding structure containing a POU-specific (POU[S]) domain joined by a flexible linker to a POU homeodomain (POU[H]). Here, we show that OCA-B alters the activity of Oct-1 in two ways. It provides a transcriptional activation domain which, unlike Oct-1, activates an mRNA-type promoter effectively, and it stabilizes Oct-1 on the Oct-1-responsive octamer sequence ATGCAAAT. These properties of OCA-B parallel those displayed by the herpes simplex virus Oct-1 coregulator VP16. OCA-B, however, interacts with a different surface of the DNA-bound Oct-1 POU domain, interacting with both the POU(S) and POU(H) domains and the center of the ATGCAAAT octamer sequence. The OCA-B and VP16 interactions with the Oct-1 POU domain are sufficiently different to permit OCA-B and VP16 to bind the Oct-1 POU domain simultaneously. These results emphasize the structural versatility of the Oct-1 POU domain in its interaction with coregulators. PMID- 9372962 TI - Transformed cells require continuous activity of RNA polymerase II to resist oncogene-induced apoptosis. AB - Studies have indicated that deregulated oncogene expression can result in either programmed cell death or proliferation, depending on the cellular microenvironment. However, little is known about whether oncogenic signals in themselves are able to activate a cellular apoptotic program. We have tested the hypothesis that oncogenic signals in the absence of gene expression are sufficient to induce cell death, which would indicate that constitutive expression of antiapoptotic genes is necessary for maintenance of the transformed state. Using two highly specific RNA polymerase (RNAP) II inhibitors, 5,6 dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) and alpha-amanitin, which inhibit RNAP II function by two distinct mechanisms, we found that inhibition of gene expression substantially increased apoptosis in a time- and dose-dependent manner in p53+/+- and p53(-/-)-transformed mouse embryonic fibroblasts and in HeLa cells, demonstrating that this type of apoptosis does not require wild-type p53. Engineered expression of an alpha-amanitin resistance RNAP II gene rendered cells resistant to induction of apoptosis by alpha-amanitin without affecting their sensitivity to DRB, indicating that alpha-amanitin induces apoptosis solely by inhibiting RNAP II function and not by a nonspecific mechanism. DRB-induced apoptosis was independent of the cell cycle or ongoing DNA replication, since DRB induced similar levels of apoptosis in asynchronous cells and cells synchronized by collection at mitosis. Inhibition of RNAP II in untransformed cells like Rat-1 or human AG1522 fibroblasts resulted not in apoptosis but in growth arrest. In contrast, deregulated expression of c-Myc in Rat-1 cells dramatically increased their sensitivity to DRB, directly demonstrating that apoptosis following inhibition of RNAP II function is greatly enhanced by oncogenic expression. The requirement for RNAP II function to prevent oncogene-induced apoptosis implies the need for the constitutive expression of an antiapoptotic gene(s) to maintain the transformed state. The differential sensitivities of untransformed and transformed cells to induction of apoptosis by transcriptional inhibition, coupled with the finding that this type of apoptosis is independent of p53 status, suggest that inhibition of RNAP II may be exploited therapeutically for the design of successful antitumor agents. PMID- 9372963 TI - High incidence of T-cell tumors in E2A-null mice and E2A/Id1 double-knockout mice. AB - The basic-helix-loop-helix (bHLH) proteins encoded by the E2A gene are broadly expressed transcription regulators which function through binding to the E-box enhancer sequences. The DNA binding activities of E2A proteins are directly inhibited upon dimerization with the Id1 gene product. It has been shown that disruption of the E2A gene leads to a complete block in B-lymphocyte development and a high frequency of neonatal death. We report here that nearly half of the surviving E2A-null mice develop acute T-cell lymphoma between 3 to 10 months of age. We further show that disruption of the Id1 gene improves the chance of postnatal survival of E2A-null mice, indicating that Id1 is a canonical negative regulator of E2A and that the unbalanced ratio of E2A to Id1 may contribute to the postnatal death of the E2A-null mice. However, the E2A/Id1 double-knockout mice still develop T-cell tumors once they reach the age of 3 months. This result suggests that E2A may be essential for maintaining the homeostasis of T lymphocytes during their constant renewal in adult life. PMID- 9372964 TI - ch-IAP1, a member of the inhibitor-of-apoptosis protein family, is a mediator of the antiapoptotic activity of the v-Rel oncoprotein. AB - The oncoprotein v-Rel, a member of the Rel/NF-kappaB family of transcription factors, induces neoplasias and inhibits apoptosis. To identify differentially regulated cellular genes and to evaluate their relevance to transformation and apoptosis in v-Rel-transformed cells, mRNA differential display has been used. One of the recovered cDNAs corresponds to a gene that was highly expressed in v Rel-transformed fibroblasts. Analysis of the isolated full-length cDNA of a chicken inhibitor-of-apoptosis protein (ch-IAP1) revealed that it encodes a 68 kDa protein that is highly homologous to members of the IAP family, such as human c-LAP1. Like other IAPs, ch-IAP1 contains the N-terminal baculovirus IAP repeats and C-terminal RING finger motifs. Northern blot analysis identified a 3.3-kb ch IAP1 transcript expressed at relatively high levels in the spleen, thymus, bursa, intestine, and lungs. Expression of v-Rel in fibroblasts, a B-cell line, and spleen cells up-regulated the expression of ch-IAP1. In contrast, ch-IAP1 expression levels were low in chicken cell lines transformed by several other unrelated tumor viruses. ch-IAP1 was expressed predominantly in the cytoplasm of the v-Rel-transformed cells. ch-IAP1 suppressed mammalian cell apoptosis induced by the overexpression of the interleukin-1-converting enzyme. Expression of exogenous ch-IAP1 in temperature-sensitive v-Rel transformed spleen cells inhibited apoptosis of these cells at the nonpermissive temperature. Collectively, these results suggest that ch-IAP1 is induced during the v-Rel mediated transformation process and functions as a suppressor of apoptosis in v Rel-transformed cells. PMID- 9372965 TI - Mutations of N-terminal regions render the retinoblastoma protein insufficient for functions in development and tumor suppression. AB - To assess biological roles of the retinoblastoma protein (RB), four independent transgenic mouse lines expressing human RB with different deletions in the N terminal region (RBdeltaN) were generated and compared with mice expressing identically regulated, full-length RB. Expression of both RB and RBdeltaN caused developmental growth retardation, but the wild-type protein was more potent. In contrast to wild-type RB, the RBdeltaN proteins were unable to rescue Rb-/- mice completely from embryonic lethality. Embryos survived until gestational day 18.5 but displayed defects in the terminal differentiation of erythrocytes, neurons, and skeletal muscle. In Rb+/- mice, expression of the RBdeltaN transgenes failed to prevent pituitary melanotroph tumors but delayed tumor formation or progression. These results strongly suggest that N-terminal regions are crucial for embryonic and postnatal development, tumor suppression, and the functional integrity of the entire RB protein. Furthermore, these transgenic mice provide models that may begin to explain human families with low-penetrance retinoblastoma and mutations in N-terminal regions of RB. PMID- 9372966 TI - CCAAT/enhancer binding protein alpha regulates p21 protein and hepatocyte proliferation in newborn mice. AB - CCAAT/enhancer binding protein alpha (C/EBP alpha) is expressed at high levels in quiescent hepatocytes and in differentiated adipocytes. In cultured cells, C/EBP alpha inhibits cell proliferation in part via stabilization of the p21 protein. The role of C/EBP alpha in regulating hepatocyte proliferation in vivo is presented herein. In C/EBP alpha knockout newborn mice, p21 protein levels are reduced in the liver, and the fraction of hepatocytes synthesizing DNA is increased. Greater than 30% of the hepatocytes in C/EBP alpha knockout animals continue to proliferate at day 17 of postnatal life when cell division in wild type littermates is low (3%). p21 protein levels are relatively high in wild-type neonates but undetectable in C/EBP alpha knockout mice. The reduction of p21 protein in the highly proliferating livers that lack C/EBP alpha suggests that p21 is responsible for C/EBP alpha-mediated control of liver proliferation in newborn mice. During rat liver regeneration, the amounts of both C/EBP alpha and p21 proteins are decreased before DNA synthesis (6 to 12 h) and then return to presurgery levels at 48 h. Although C/EBP alpha controls p21 protein levels, p21 mRNA is not influenced by C/EBP alpha in liver. Using coimmunoprecipitation and a mammalian two-hybrid assay system, we have shown the interaction of C/EBP alpha and p21 proteins. Study of p21 stability in liver nuclear extracts showed that C/EBP alpha blocks proteolytic degradation of p21. Our data demonstrate that C/EBP alpha regulates hepatocyte proliferation in newborn mice and that in liver, the level of p21 protein is under posttranscriptional control, consistent with the hypothesis that protein-protein interaction with C/EBP alpha determines p21 levels. PMID- 9372969 TI - Adenovirus-mediated overexpression of IRS-1 interacting domains abolishes insulin stimulated mitogenesis without affecting glucose transport in 3T3-L1 adipocytes. AB - Activated insulin receptor (IR) interacts with its substrates, IRS-1, IRS-2, and Shc via the NPXY motif centered at Y960. This interaction is important for IRS-1 phosphorylation. Studies using the yeast two-hybrid system and sequence identity analysis between IRS-1 and IRS-2 have identified two putative elements, the PTB and SAIN domains, between amino acids 108 and 516 of IRS-1 that are sufficient for receptor interaction. However, their precise function in mediating insulin's bioeffects is not understood. We expressed the PTB and SAIN domains of IRS-1 in HIRcB fibroblasts and 3T3-L1 adipocytes utilizing replication-defective adenoviral infection to investigate their role in insulin signalling. In both cell types, overexpression of either the PTB or the SAIN protein caused a significant decrease in insulin-induced tyrosine phosphorylation of IRS-1 and Shc proteins, IRS-1-associated phosphatidylinositol 3-kinase (PI 3-K) enzymatic activity, p70s6k activation, and p44 and p42 mitogen-activated protein kinase (MAPK) phosphorylation. However, epidermal growth factor-induced Shc and MAPK phosphorylation was unaffected by the overexpressed proteins. These findings were associated with a complete inhibition of insulin-stimulated cell cycle progression. In 3T3-L1 adipocytes, PTB or SAIN expression extinguished IRS-1 phosphorylation with a corresponding 90% decrease in IRS-1-associated PI 3-K activity. p70s6k is a downstream target of PI 3-K, and insulin-stimulated p70s6k was inhibited by PTB or SAIN expression. Interestingly, overexpression of either PTB or SAIN protein did not affect insulin-induced AKT activation or insulin stimulated 2-deoxyglucose transport, even though both of these bioeffects are inhibited by wortmannin. Thus, interference with the IRS-1-IR interaction inhibits insulin-stimulated IRS-1 and Shc phosphorylation, PI 3-K enzymatic activity, p70s6k activation, MAPK phosphorylation and cell cycle progression. In 3T3-L1 adipocytes, interference with the IR-IRS-1 interaction did not cause inhibition of insulin-stimulated AKT activation or glucose transport. These results indicate a bifurcation or subcompartmentalization of the insulin signalling pathway whereby some targets of PI 3-K (i.e., p70s6k) are dependent on IRS-1-associated PI 3-K and other targets (i.e., AKT and glucose transport) are not. IR-IRS-1 interaction is not essential for insulin's effect on glucose transport, and alternate, or redundant, pathways exist in these cells. PMID- 9372967 TI - A dominant-negative cyclin D1 mutant prevents nuclear import of cyclin-dependent kinase 4 (CDK4) and its phosphorylation by CDK-activating kinase. AB - Cyclins contain two characteristic cyclin folds, each consisting of five alpha helical bundles, which are connected to one another by a short linker peptide. The first repeat makes direct contact with cyclin-dependent kinase (CDK) subunits in assembled holoenzyme complexes, whereas the second does not contribute directly to the CDK interface. Although threonine 156 in mouse cyclin D1 is predicted to lie at the carboxyl terminus of the linker peptide that separates the two cyclin folds and is buried within the cyclin subunit, mutation of this residue to alanine has profound effects on the behavior of the derived cyclin D1 CDK4 complexes. CDK4 in complexes with mutant cyclin D1 (T156A or T156E but not T156S) is not phosphorylated by recombinant CDK-activating kinase (CAK) in vitro, fails to undergo activating T-loop phosphorylation in vivo, and remains catalytically inactive and unable to phosphorylate the retinoblastoma protein. Moreover, when it is ectopically overexpressed in mammalian cells, cyclin D1 (T156A) assembles with CDK4 in the cytoplasm but is not imported into the cell nucleus. CAK phosphorylation is not required for nuclear transport of cyclin D1 CDK4 complexes, because complexes containing wild-type cyclin D1 and a CDK4 (T172A) mutant lacking the CAK phosphorylation site are efficiently imported. In contrast, enforced overexpression of the CDK inhibitor p21Cip1 together with mutant cyclin D1 (T156A)-CDK4 complexes enhanced their nuclear localization. These results suggest that cyclin D1 (T156A or T156E) forms abortive complexes with CDK4 that prevent recognition by CAK and by other cellular factors that are required for their nuclear localization. These properties enable ectopically overexpressed cyclin D1 (T156A), or a more stable T156A/T286A double mutant that is resistant to ubiquitination, to compete with endogenous cyclin D1 in mammalian cells, thereby mobilizing CDK4 into cytoplasmic, catalytically inactive complexes and dominantly inhibiting the ability of transfected NIH 3T3 fibroblasts to enter S phase. PMID- 9372968 TI - I kappaB alpha physically interacts with a cytoskeleton-associated protein through its signal response domain. AB - The I kappaB alpha protein is a key molecular target involved in the control of NF-kappaB/Rel transcription factors during viral infection or inflammatory reactions. This NF-kappaB-inhibitory factor is regulated by posttranslational phosphorylation and ubiquitination of its amino-terminal signal response domain that targets I kappaB alpha for rapid proteolysis by the 26S proteasome. In an attempt to identify regulators of the I kappaB alpha inhibitory activity, we undertook a yeast two-hybrid genetic screen, using the amino-terminal end of I kappaB alpha as bait, and identified 12 independent interacting clones. Sequence analysis identified some of these cDNA clones as Dlc-1, a sequence encoding a small, 9-kDa human homolog of the outer-arm dynein light-chain protein. In the two-hybrid assay, Dlc-1 also interacted with full-length I kappaB alpha protein but not with N-terminal-deletion-containing versions of I kappaB alpha. I kappaB alpha interacted in vitro with a glutathione S-transferase-Dlc-1 fusion protein, and RelA(p65) did not displace this association, demonstrating that p65 and Dlc-1 contact different protein motifs of I kappaB alpha. Importantly, in HeLa and 293 cells, endogenous and transfected I kappaB alpha coimmunoprecipitated with Myc tagged or endogenous Dlc-1. Indirect immunofluorescence analyzed by confocal microscopy indicated that Dlc-1 and I kappaB alpha colocalized with both nuclear and cytoplasmic distribution. Furthermore, Dlc-1 and I kappaB alpha were found to associate with the microtubule organizing center, a perinuclear region from which microtubules radiate. Likewise, I kappaB alpha colocalized with alpha-tubulin filaments. Taken together, these results highlight an intriguing interaction between the I kappaB alpha protein and the human homolog of a member of the dynein family of motor proteins and provide a potential link between cytoskeleton dynamics and gene regulation. PMID- 9372971 TI - Molecular cloning and characterization of human JNKK2, a novel Jun NH2-terminal kinase-specific kinase. AB - At least three mitogen-activated protein kinase (MAPK) cascades were identified in mammals, each consisting of a well-defined three-kinase module composed of a MAPK, a MAPK kinase (MAPKK), and a MAPKK kinase (MAPKKK). These cascades play key roles in relaying various physiological, environmental, or pathological signals from the environment to the transcriptional machinery in the nucleus. One of these MAPKs, c-Jun N-terminal kinase (JNK), stimulates the transcriptional activity of c-Jun in response to growth factors, proinflammatory cytokines, and certain environmental stresses, such as short wavelength UV light or osmotic shock. The JNKs are directly activated by the MAPKK JNKK1/SEK1/MKK4. However, inactivation of the gene encoding this MAPKK by homologous recombination suggested the existence of at least one more JNK-activating kinase. Recently, the JNK cascade was found to be structurally and functionally conserved in Drosophila, where DJNK is activated by the MAPKK DJNKK (hep). By a database search, we identified an expressed sequence tag (EST) encoding a portion of human MAPKK that is highly related to DJNKK (hep). We used this EST to isolate a full length cDNA clone encoding a human JNKK2. We show that JNKK2 is a highly specific JNK kinase. Unlike JNKK1, it does not activate the related MAPK, p38. Although the regulation of JNKK1 activities and that of JNKK2 activities could be very similar, the two kinases may play somewhat different regulatory roles in a cell type-dependent manner. PMID- 9372970 TI - Complementation of growth factor receptor-dependent mitogenic signaling by a truncated type I phosphatidylinositol 4-phosphate 5-kinase. AB - Substitution of phenylalanine for tyrosine at codon 809 (Y809F) of the human colony-stimulating factor 1 (CSF-1) receptor (CSF-1R) impairs ligand-stimulated tyrosine kinase activity, prevents induction of c-MYC and cyclin D1 genes, and blocks CSF-1-dependent progression through the G1 phase of the cell cycle. We devised an unbiased genetic screen to isolate genes that restore the ability of CSF-1 to stimulate growth in cells that express mutant CSF-1R (Y809F). This screen led us to identify a truncated form of the murine type Ibeta phosphatidylinositol 4-phosphate 5-kinase (mPIP5K-Ibeta). This truncated protein lacks residues 1 to 238 of mPIP5K-Ibeta and is catalytically inactive. When we transfected cells expressing CSF-1R (Y809F) with mPIP5K-Ibeta (delta1-238), CSF-1 dependent induction of c-MYC and cyclin D1 was restored and ligand-dependent cell proliferation was sustained. CSF-1 normally triggers the rapid disappearance of CSF-1R (Y809F) from the cell surface; however, transfection of cells with mPIP5K Ibeta (delta1-238) stabilized CSF-1R (Y809F) expression on the cell surface, resulting in elevated levels of ligand-activated CSF-1R (Y809F). These results suggest a role for PIP5K-Ibeta in receptor endocytosis and that the truncated enzyme compensated for a mitogenically defective CSF-1R by interfering with this process. PMID- 9372973 TI - The role of renal replacement therapy quantification in acute renal failure. AB - The recognition that both morbidity and mortality are inversely related to delivered hemodialysis (HD) dose in end-stage renal disease (ESRD) patients has substantially changed clinical practices in the United States. A number of quantification techniques, which differ greatly in complexity and sophistication, are now used in ESRD patients. Investigators recently have attempted to extrapolate some of these ESRD quantification methods to the acute renal failure (ARF) setting. This review focuses on these recent attempts. Both patient-related and renal replacement therapy (RRT)-related differences in ESRD and ARF are discussed. In addition, the potential pitfalls of extrapolating certain ESRD quantification methods to RRT in ARF are discussed. Prescription considerations for both intermittent HD (IHD) and continuous RRT (CRRT) are presented. The optimal technique for RRT quantification in ARF remains to be determined. PMID- 9372974 TI - New CRRT systems: impact on dose delivery. AB - The evolution of technology and biomaterials has permitted a parallel development of renal replacement therapies in the acute, critically ill patient. From the original description of continuous arteriovenous hemofiltration, new techniques such as continuous venovenous hemofiltration, hemodiafiltration, and high flux dialysis have been developed and clinically used. A parallel improvement in efficiency has been achieved with urea daily clearances as high as 50 L or more. The use of special highly permeable dialyzers has also permitted an increase in the clearances of larger solutes, thus leading to significant removals of chemical substances involved in acute inflammation and sepsis. In this field, recent observations have suggested using hemofiltration with high volumes of fluid exchange. The hardware and software of the newer CRRT systems are key in achieving these results and in safely performing such challenging techniques. PMID- 9372972 TI - Urea kinetic modeling for CRRT. AB - Urea kinetic modeling (UKM) for dialysis quantification and prescription, although widely used in chronic renal failure (CRF), has been largely absent in the acute setting. A quantitative approach to prescription of continuous renal replacement therapies (CRRTs) for acute renal failure (ARF) based on UKM is presented. For patients with a relatively constant urea generation rate, G, who are receiving a fixed dose of CRRT, blood urea nitrogen (BUN) falls in an exponential fashion, approaching a plateau level after 3 to 4 days of continuous treatment. The CRRT clearance, K, necessary to achieve a desired plateau value of BUN, Cgoal, may be computed as G/Cgoal x K for all but predilutional CRRT modalities may be calculated as equal to the effluent (dialysate plus ultrafiltrate) flow rate from the filter. Urea mass balance equations are proposed for the determination of patient G value either during the pretreatment rise in BUN or during the decline in BUN with CRRT. In the absence of a reliable estimate of patient G, a reasonable CRRT starting prescription is to set the filter effluent rate in liters per hour (approximately K) to 1.2 times the patient's body weight in kilograms divided by the desired Cgoal in milligrams per deciliter. This relationship assumes moderate hypercatabolism (normalized protein catabolic rate = 2.0 g/kg/d) and patient urea distribution volume equal to 60% of body weight. For Cgoal = 60 mg/dL, this reduces to an easily remembered formula for K (in L/hr) of twice the patient's body weight divided by 100. PMID- 9372975 TI - The coagulation system in the critically ill patient with acute renal failure and the effect of an extracorporeal circuit. AB - Continuous renal replacement therapy (CRRT) has been advocated as the treatment of choice in critically ill patients with renal failure. However, to be as effective as intermittent hemodialysis in terms of small molecule clearance, the extracorporeal CRRT circuit must operate continuously, 24 hours a day, day after day. This review examines both patient and extracorporeal factors that may lead to premature clotting within the CRRT circuit, and approaches that may reduce extracorporeal clotting. PMID- 9372976 TI - The bioartificial renal tubule assist device to enhance CRRT in acute renal failure. AB - Current therapy for acute tubular necrosis (ATN) continues to have an exceedingly high mortality rate, exceeding 50% even with dialytic or hemofiltrative support. Current renal replacement therapy in ATN only substitutes for filtration function of the kidney but not its cellular metabolic functions. Replacing these metabolic functions may optimize current therapy for this devastating disease process. In this regard, a renal tubule assist device (RAD) has been developed to be placed in an extracorporeal continuous hemoperfusion circuit in series with a hemofilter. The RAD consists of porcine renal proximal tubule cells grown as confluent monolayers of a multifiber bioreactor with a membrane surface area from 0.4 to 1.6 m2. The cells along the inner surface of the hollow fibers are immunoprotected from the patient's blood by the hollow fiber membrane. In preliminary experiments in uremic dogs, this device has been shown to tolerate a uremic environment while providing reabsorptive, metabolic, and endocrinologic activity. Pilot human trials of the RAD are anticipated within the next year to improve current renal replacement therapy in ATN. PMID- 9372977 TI - Dialysis membrane adsorption during CRRT. AB - Experimental and clinical studies have suggested that dialysis membrane biocompatibility may influence the morbidity and mortality of patients with acute renal failure. Complement activation by dialysis membranes may also prolong the recovery from acute renal failure. In this article, we review the concept of dialysis membrane adsorption, with particular attention to adsorption/inhibition of factor D, a highly specific serine protease of the alternative pathway of complement. The adsorptive properties of some dialysis membranes may be useful during continuous renal replacement therapies (CRRT) in critically ill patients. PMID- 9372978 TI - Mediator removal with CRRT: complement and cytokines. AB - The evidence from animal sepsis models that hemofiltration may ameliorate the hemodynamic changes that occur in septic shock has led to speculation that continuous renal replacement therapy may have nonrenal benefits in septic patients. Much of the subsequent work has been done to elucidate the mechanisms of this benefit, in particular the role of removal of inflammatory mediators including cytokines and complement. The significance of extracorporeal removal of such products is dependent on the relative importance of endogenous production and clearance in the setting of sepsis and multiple organ failure and on the method of blood purification. This article reviews the evidence thus far, consisting of in vitro, animal, and human studies; a range of mediators (TNFalpha, IL-1beta, IL-6, IL-8, complement factors C3a, C5a, and D); various membranes (polyacrylonitrile, polysulfone, and polyamide); and clearance by diffusion, convection, and adsorption. The most consistent results suggest that the plasma levels of some mediators are lowered by a combination of membrane adsorption and convection, the clinical significance of which is still uncertain. The review shows the need for further work to unravel the role of CRRT in treating septic patients. PMID- 9372979 TI - Extracorporeal adsorbent-based strategies in sepsis. AB - Gram-negative bacterial sepsis remains a challenging diagnostic and therapeutic dilemma to the practicing clinician. Bacterial-derived products (eg, gram negative bacterial lipopolysaccharide or endotoxin) and host inflammatory mediators (eg, tumor necrosis factor-alpha and interleukin-1) are believed to play a pivotal role in the pathogenesis of sepsis and septic shock. Despite the many advances in the treatment of sepsis, mortality rates in septic patients remain high. Indeed, numerous clinical trials using biologically engineered immunotherapies targeting specific inflammatory mediators have proven unsuccessful. This lack of success has led to a renewed interest in blood purification techniques using extracorporeal therapies. During sepsis, circulating bacterial-derived products as well as inflammatory mediators can be reduced and/or eliminated by various extracorporeal adjunctive therapies such as plasma exchange, continuous renal replacement, and adsorbent-based therapies. Adsorbents have commonly been used orally for gastrointestinal removal of toxins or drugs. However, their potential use in sepsis has received little attention. The incorporation of adsorbents in hemoperfusion columns has allowed their use for the removal of toxic compounds from the circulatory system. Adsorbents developed for use in sepsis can bind toxins in a nonselective (eg, charcoal), selective (eg, polymyxin B-immobilized polystyrene-derivative fiber), or specific (eg, antibody-coated microsphere-based detoxification system) way. However, despite an explosive development in the experimental use of these promising therapies, randomized clinical trials are currently lacking. In summary, a multi disciplinary complex therapeutic approach remains a prerequisite to the successful treatment of sepsis. PMID- 9372980 TI - Relevance of platelet-activating factor in inflammation and sepsis: mechanisms and kinetics of removal in extracorporeal treatments. AB - Sepsis can be considered a systemic inflammatory response syndrome (SIRS) caused by infection. When an excessive and/or persistent activation of humoral and cellular mechanisms of host defense is present, an exaggerated and generalized activation of inflammatory mechanisms can lead to a multiple organ dysfunction syndrome. Mediators thought to be involved in this syndrome include the major plasma cascade systems (complement, coagulation, and fibrinolytic systems) and soluble cell-derived mediators (cytokines, reactive oxygen species, platelet activating factor (PAF), arachidonic acid metabolites, and nitric oxide and related compounds). Several findings indicate that among these mediators, PAF may exert an important role in the pathophysiology of septic shock. Evidence is accumulating that in human sepsis this scenario is far more complicated and that removal of inflammatory mediator excess from plasma, rather than blockade of their potentially beneficial local production, might provide a rationale for the use of continuous renal replacement therapy (CRRT). There is an emerging view that CRRT should be considered in the light of broader concept (ie, the use of blood purification for the treatment of sepsis). Recent studies, performed in an experimental model of continuous arteriovenous hemofiltration with exogenous PAF, demonstrated that polysulfone membranes can adsorb substantial amounts of biologically active PAF. These studies also showed that the removal of this mediator occurs by a two-step process involving early adsorption followed by ultrafiltration. Although the removal of cytokines, such as tumor necrosis factor alpha (TNF-alpha), remains controversial, mainly because of differences in membrane used, operational conditions, and inter- and intra-assay variability, the crucial point is that no evidence has yet been given to show real benefit from CRRT in significantly reducing the plasma concentration of cytokines. The net advantage of CRRT, however, may not only be the removal of cytokines per se, but also the simultaneous elimination of cytokine-inducing substances. Experimental and human studies will be discussed as to whether extracorporeal treatments may remove an excess of circulating cytokines, either by increasing the turnover rate (the so-called high-volume hemofiltration), or by using sorbent systems to regenerate plasma filtrate. PMID- 9372981 TI - Extracorporeal liver support: cell-based therapy for the failing liver. AB - It is perhaps self-evident to state that a liver support device is possible as long as the artificial organ provides liver function. This basic concept has received woefully little attention, mainly because "liver function" escapes precise definition. We have seen a variety of liver-assist devices that have little to do with liver function over the past 30 years. Recent work has focused on the liver as a biochemical reactor, rather than an excretory organ, and the paradigm has shifted away from blood purification and toward metabolic support. This new generation of devices includes viable liver cells, which provide the necessary biochemical function without needing to identify the numerous metabolic pathways necessary to support the patient with a failing liver. This approach is the most effective and least invasive method available with current technology, and it has yielded exciting data. Questions about the mass of cells required to provide adequate support, the timing and length of treatment, and the source of cellular material continue to be debated. Here we address theoretical and practical problems in developing an extracorporeal liver-assist device (ELAD) and suggest the future role of extracorporeal liver support in the management of liver failure. PMID- 9372982 TI - Intermittent versus continuous treatment for acute renal failure: where do we stand? AB - Despite impressive advances in the field of general intensive care and in the techniques available for the treatment of acute renal failure (ARF), particularly the development of continuous renal replacement therapies (CRRT), it is suggested that outcome of ARF patients has remained similar to that observed 2 or more decades ago. This article focuses on the impact of several factors, including the dialysis regimen, on outcome in ARF patients in a recent time period compared with an earlier period to assess whether a change has occurred in the patient population, dialysis regimen, or renal and patient outcome. Critical differences between intermittent hemodialysis (IHD) and CRRT and the authors' preference for continuous venovenous hemofiltration (CWH) are explained. However, using the APACHE II score and more specifically use of the ratio between this score at 2 different time points (ICU admission v time of start of dialysis), the need for an easy-to-use and reliable severity-of-illness score to allow adequate comparison of patient groups or treatment strategies is emphasized. Using data from a recent survey, attention is also given to the implementation of acute dialytic support, particularly CRRT, in the Netherlands. PMID- 9372983 TI - Renal replacement therapy in the ICU: the Australian experience. AB - The structure of health care drives medical practice in a powerful way, shaping choices of therapy and approaches, and influencing scientific evidence. The Australian experience with continuous renal replacement therapy (CRRT) confirms the importance of structure. A public health system like that of Australia's contains the following variables: well-developed intensive care tradition and expertise, a dominant "closed" intensive care unit (ICU) model, well-developed training of intensive care nurses with established one-to-one nurse-patient ratios, salaried medical practitioners, overworked general dialysis units with inadequate nursing resources, and lack of fee-for-service incentive for nephrologists to see ICU patients with acute renal failure. The likely outcome of such a system is for CRRT to be run by intensive care staff. As shown by a recent regional survey, this approach, although somewhat unique, is dominant and appears to work well with excellent clinical results and constant clinical research output. PMID- 9372985 TI - Emerging therapies for acute renal failure. AB - Ischemia is the most common cause of acute renal failure (ARF). In the last decade, several new and important pathophysiological mechanisms that underlie the renal dysfunction have been discovered. These pathophysiological mechanisms include the role of both calcium and calcium-dependent enzymes, oxidant stress, loss of polarity of the tubular cell, tubular obstruction and arginine-glycine aspartic acid (RGD) peptides, neutrophils, intracellular adhesion molecules (ICAM), and growth factors. A better understanding of tubular and vascular mechanisms has led to therapeutic studies in animals and clinical trials in humans. In this review, the pathophysiology of ischemic ARF will be correlated with the rationale for both current and future therapies. PMID- 9372984 TI - Management of acute renal failure in the pediatric patient: hemofiltration versus hemodialysis. AB - Although outcome data for acute renal failure (ARF) in the adult population (analyzed by etiology of ARF, severity of illness, and modality of treatment) are readily available, few similar data exist for the pediatric population. Pediatric survival rate data vary widely, based upon era of analysis, age and size of child, and cause of ARF. Few comparative data are available that address impact by modality chosen to treat ARF. Comparison of 122 children who were treated by hemodialysis (HD; n = 58) versus hemofiltration (HF; n = 64) reveals a combined survival rate of 65%. Survival by modality was higher for HD (83%) than for HF (48%). The major diagnosis treated with HF was sepsis (29/64; 45%), with a survival rate of 31%, whereas the major diagnosis treated with HD (27/58; 46%) was primary renal failure, with a survival rate of 96%. Seventy-one percent of children undergoing HF required pressor support for hypotension, whereas only 24% of those receiving HD needed pressor support (P < 0.01). We conclude that the choice of renal replacement therapy (RRT) modality needs to be determined by the best treatment available. To adequately evaluate therapy measures, further analyses of outcome need to consider those factors that determine choice of RRT and those that affect survival independent of ARF. PMID- 9372986 TI - On the design and analysis of multicenter trials in acute renal failure. AB - Improving outcomes for patients with acute renal failure (ARF) is one of the most urgent tasks for 21st century nephrologists and other critical care physicians. The incidence of hospital-acquired ARF is rising (to 5% or more), partly because of changes in the demographic and clinical characteristics of the hospitalized patient population. When ARF is severe enough to require dialysis, in-hospital mortality rates are distressingly high, in excess of 50% in most published studies. In the past several years, a number of attempts have been made to influence the course of ARF, either relatively early (eg, atrial natriuretic peptide [ANP], insulin growth factor-1 [IGF-1]) or coincident with the dialysis procedure in severe cases (eg, variations in dialysis membrane and modality). Several lessons can be learned from these efforts. This article will briefly address issues in the design and analysis of clinical trials, focusing on elements of special interest to practitioners of renal medicine. PMID- 9372987 TI - CRRT in the area of cost containment: is it justified? AB - Intensive care accounts for at least 25% of health care costs. One third of this goes to 10% of patients who, in general, have combined respiratory and renal failure. The cost of renal replacement therapy is, therefore, of major importance. Continuous renal replacement therapy (CRRT) has many potential advantages over intermittent hemodialysis (IHD). These include better nutritional support, better volume maintenance, reduction of extravascular lung water, and potential clearance of inflammatory mediators. To date, noncomparative trials have suggested a trend toward decreased mortality. Randomized trials have suggested a CRRT mortality and morbidity benefit, but only when comparing long term renal recovery. Acute mortality benefit has not been clearly established and, as such, cost comparison is of increased interest. Cost comparison trials are complicated, but some recent studies have led to the conclusion that costs are comparable. Others have concluded that CRRT is slightly more expensive. When comparing randomized patients in a recent prospective trial, aggregate costs for renal replacement therapy were comparable. The advantages of better nutrition, better fluid balance, easier management of hemodynamics, and more complete renal recovery, as suggested by this study, should continue to make it valuable. Physician acceptance of CRRT advantages has been established and suggests clinical benefit despite any potential increased cost. PMID- 9372988 TI - Who should manage CRRT in the ICU? The nursing viewpoint. AB - Continuous renal replacement therapy (CRRT) is performed in critical care units around the world with various levels of involvement from critical care and nephrology nurses. In this article, factors affecting the delivery of nursing care and the particular expertise nephrology and critical care nurses have in the area of CRRT are examined. Based on this discussion, three proposed models of nursing care for the patient receiving CRRT are discussed: the Nephrology Nursing Model, the Critical Care Model, and the Collaborative Model. Based on related research findings and a comparison of the models, the Collaborative Model is the preferred one, as it brings the highest level of expertise directly to the patient. For the Collaborative Model to work, a framework for collaboration and a high degree of commitment from both specialties must be maintained. PMID- 9372990 TI - Training, management, and credentialing for CRRT in the ICU. AB - Continuous renal replacement therapy (CRRT) in the intensive care unit (ICU) requires a dedicated training and educational process that includes both theoretical and practical approaches. Important goals for this process include achieving an acceptable circuit life without patient complications and providing a high percentage of staff with bedside expertise. Lectures or didactic sessions must link into bedside instruction and simulations or mock patient/circuit setup. An annual seminar may be useful for all clinicians to share and gain knowledge. Managers require a system of staff review to ensure expertise levels are maintained. Policy development, quality assurance, and complication monitoring systems provide useful information for managers and educators in this field. Credentialing may be useful to confirm the goals of CRRT, but it requires further development of practice standards before adoption. PMID- 9372989 TI - Who should manage CRRT in the ICU? The intensivist's viewpoint. AB - The arrival of continuous renal replacement therapy (CRRT) has given the intensivist and the intensive care nurse the opportunity to treat acute renal failure (ARF) independently by giving them the necessary technology and taking CRRT away from absolute nephrological control. This structural shift has created a controversy between those countries where control of CRRT has completely shifted to the intensivist and those countries where nephrological input is still dominant. The argument in favor of intensivist-driven CRRT rests upon several observations, including the fact that therapy is continuous, as is the presence of the intensivist in the intensive care unit (ICU). Critically ill patients require rapid changes in treatment that are best directed by physicians who are at the bedside all the time. CRRT must be seen within the totality of patient care, and the intensivist can see the larger picture more accurately. Intensivists are successfully performing more and more procedures that were previously seen as part of other specialties and, last but not least, "closed" models of ICU care appear to work best. Australian intensivists have taken up CRRT from the start and now control it. Patient outcomes under such a system, as reported here, are above average, and confirm the effectiveness of such an approach. PMID- 9372991 TI - Atherogenesis and ischemic heart disease. PMID- 9372992 TI - Effects of lipid lowering on coronary plaques and coronary events. PMID- 9372993 TI - Review of recent clinical trials of lipid lowering in coronary artery disease. AB - Early trials with lipid-lowering therapy in patients with established coronary artery disease revealed favorable trends in cardiovascular events but did not yield significant reductions in total mortality. Recent clinical trials using hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor ("statin") therapy have shown significant decreases in total mortality, cardiovascular events, hospitalizations, and the need for revascularization procedures, with its usage (1) to lower low-density lipoprotein (LDL) cholesterol after myocardial infarction (secondary prevention); and (2) in high-risk patients without evidence for coronary artery disease (primary prevention). Secondary prevention benefits have been seen for both men and women, in the young and elderly, and among diabetic and nondiabetic patients. The beneficial effects of LDL-cholesterol reduction occur early and are additive to other risk-reduction therapies. Lipid lowering therapy should be part of the comprehensive treatment of all patients with atherosclerotic vascular disease and patients at high risk. PMID- 9372994 TI - Pharmacotherapy for systolic dysfunction: a review of randomized clinical trials. AB - Chronic heart failure (HF) is a leading cause of morbidity and mortality in the United States, affecting >4 million people. The increasing prevalence of HF has placed an enormous burden on the US healthcare system. For many patients with cardiovascular disease, HF is the final common pathway. Treatment strategies for HF are aimed at preventing and delaying progression of the disease and ultimately improving survival. This article reviews recent clinical drug trials for HF, including angiotensin-converting enzyme (ACE) inhibitors, angiotensin II antagonists, vasodilators, beta-adrenergic blockers, positive inotropic agents, calcium antagonists, and antiarrhythmics. The benefits and shortcomings of these agents and the study designs are discussed. For patients with left ventricular (LV) systolic dysfunction, ACE inhibitors are the only agents that consistently improved survival and decreased the rate of HF progression. It is likely that beta-adrenergic blockers have the same effect. The syndrome of HF is complex with both peripheral and cardiac factors contributing to disease progression. The addition of a diuretic and/or digoxin is often needed to prevent worsening heart failure. Although an angiotensin II antagonist may also be beneficial in the treatment of HF, further studies are needed to clarify their precise role in the management of this condition. Calcium anatagonists, antiarrhythmics excluding amiodarone, and positive inotropes other than digoxin do not appear to prevent progression of HF nor improve survival. The most common cause of HF in the United States is related to coronary artery disease. Reduction of cardiac risk factors, such as smoking cessation, lowering serum cholesterol with diet and a lipid lowering agent, and blood pressure control, is likely to prevent the development or progression of HF. PMID- 9372995 TI - The role of financial incentives in shaping clinical practice patterns and practice efficiency. AB - The US healthcare system is evolving from one in which most providers have been paid on some variation of a fee-for-service basis to one in which many or most providers will be paid on a capitated basis. Will this change in financial incentives make a difference in how coronary artery disease and heart failure are treated and managed? Although the evidence is equivocal and limited, two recent studies suggest that capitation and other global payment incentives may dramatically alter clinical practice patterns in treating cardiovascular disease and substantially reduce cardiac-care costs. Clinical cost-effectiveness research efforts must be intensified. Thought leaders in the field of cardiology must move forcefully in developing, disseminating, and encouraging cardiac-care providers to accept and implement evidence-based clinical practice guidelines. The alternative may be ill-advised tradeoffs decided in a decentralized, competitive marketplace, with algorithms being developed de facto by individual practitioners or groups in response to capitated reimbursement constraints. The resulting practice could reduce healthcare use and spending without being cost-effective. Unexpected and undesirable health outcomes could ensue. PMID- 9372996 TI - Economics of treating heart failure. AB - Over 400,000 people in the United States are diagnosed with congestive heart failure (CHF) annually. The 3 major causes of acute cardiac hospitalizations in the United States--CHF, unstable angina, and acute myocardial infarction--all reflect a failure to prevent progression of established cardiovascular disease. More effective treatment strategies for CHF should be directed at preventing rehospitalization through modification of cardiac risk factors. Several large clinical trials have demonstrated that angiotensin-converting enzyme (ACE) inhibitors, while considered preferred therapy, are routinely underutilized by all healthcare practitioners. Digoxin has also been shown in several clinical trials to reduce the need for rehospitalization in CHF patients. Finally, patients' quality of life and the morbidity associated with CHF can be reduced through well-structured disease management programs in conjunction with ACE inhibitor and digoxin therapy. PMID- 9372997 TI - Management of hypercholesterolemia: practice patterns for primary care providers and cardiologists. AB - This retrospective study, conducted as part of a private practice quality assurance process for patients with coronary artery disease (CAD), compares practice patterns in the LIFEHELP lipid clinic and non-lipid clinic settings at the Heart Institute of St. Petersburg. Quality assurance parameters included documentation of low-density lipoprotein (LDL) cholesterol, initiation of lipid lowering therapy, and achievement of the Second National Cholesterol Education Program (NCEP II) goal for CAD patients of LDL cholesterol < or =100 mg/dL. A total of 934 patient charts with ICD-9 codes of 410-414 for ischemic heart disease were randomly selected and reviewed by a utilization review nurse. A higher level of documentation and treatment of elevated LDL cholesterol to NCEP II goal in CAD patients was found for those followed in the lipid clinic. Among non-lipid clinic physicians, cardiologists documented and treated elevated LDL cholesterol more frequently than primary care physicians. Women and the elderly subgroups received improved care in the lipid clinic setting. Screening activities and risk-factor management by cardiologists within a lipid clinic, therefore, demonstrated an improved standard of care that came closer to achieving national guidelines in the secondary prevention of CAD. PMID- 9372998 TI - The treatment gap in coronary artery disease and heart failure: community standards and the post-discharge patient. AB - Progress in vascular biology, epidemiology, clinical trials, and cost effectiveness analyses have allowed development of guidelines for risk reduction in patients with vascular disease and congestive heart failure. However, these advances appear necessary but not sufficient to promote implementation of these guidelines for treating coronary artery disease (CAD) and congestive heart failure (CHF). Evidence from the United Kingdom and Europe, and estimates from the United States, suggest that a large "treatment gap" exists between recommended therapies for patients with cardiovascular disease and the care that they are actually receiving. Despite known interventions with proven efficacy to reduce disease recurrence and death from CAD and CHF, only a minority of patients are receiving any intervention whatsoever. A second problem is that, among those receiving care, many are undertreated resulting in a very small number of patients reaching goals and recommended levels of therapy. Third, the levels of intervention and the proportion of patients at goal that should be attainable (i.e., community standards) are not known. A variety of barriers exist for implementation of preventive cardiology services. Although the patient has a chain of opportunities for risk reduction, it is not clear which of the links in this chain (inpatient/hospital programs, specialist/generalist communication, ambulatory care, or patient compliance) is the major reason for the treatment gap. An ongoing project, the American College of Cardiology Evaluation of Preventive Therapeutics (ACCEPT), will attempt to quantify the treatment gap in coronary disease patients in the United States and will try to identify those barriers playing the greatest role in limiting the optimal care of the coronary disease patient. PMID- 9372999 TI - Performance assessment model for guideline-recommended pharmacotherapy in the secondary prevention of coronary artery disease and treatment of left ventricular dysfunction. AB - The Agency for Health Care Policy and Research, the National Heart Lung and Blood Institute of the National Institutes of Health, the American Heart Association, and the American College of Cardiology have all developed guidelines for improving the care of patients with cardiovascular disease. The guidelines include recommendations for intensive lipid-lowering therapy in patients with coronary artery disease (CAD) and angiotensin-converting enzyme (ACE) inhibitors in those patients with symptomatic heart failure and asymptomatic left ventricular dysfunction. Despite clinical trial evidence and consensus that these therapies improve survival in high-risk patients, data suggest that there is wide variation in the delivery of guideline-based care. To investigate whether evidence-based assessment of provider practice patterns can impact the delivery of quality cost-effective care, Merck and Company, in conjunction with leading cardiology group practices, the University of North Carolina at Chapel Hill, and Medical Review of North Carolina developed an ambulatory medical record abstraction study. This quality assurance initiative was conducted at practices beginning in the spring of 1996 and continues. Medical records and administrative claims of patients with ischemic heart disease or heart failure were abstracted by a healthcare consulting organization to maintain patient and physician confidentiality. As of mid-July 1997, 626 group practices had completed the medical record abstraction process, with > 1,136 practices participating at some stage of the project; >6,000 physicians participated in the project and >270,000 patients charts were abstracted. Analysis of these data will provide insight and benchmark patterns of care in the pharmacologic management of heart failure and CAD. This project represents a unique collaboration between a pharmaceutical company, an academic institution, a Peer Review Organization, and practicing physicians, to support evidence-based best medical practices. PMID- 9373000 TI - Implementing quality assurance programs in multigroup practices for treating hypercholesterolemia in patients with coronary artery disease. AB - Healthcare reform is driving the development of specialty physician practices into larger regional and national physician networks. These networks arise from the federation of > or =2 practices that negotiate with managed-care organizations for contracts. Developing cardiovascular networks and establishing and implementing lipid management quality assurance programs into the network are presented in this article. Goals of the lipid management program include enhancing the identification, diagnosis, education, and comprehensive treatment of patients with cardiovascular disease. Utilizing an integrated, coordinated, multidisciplinary approach to lipid management allows the cardiology network to improve patients' quality of life, reduce long-term costs, and gain a competitive advantage for successful contracting. A network lipid management program involves targeting eligible patients and treating them to a targeted level for low-density lipoprotein (LDL) cholesterol where possible. Among cardiologists, there is a consensus that achieving an LDL cholesterol of < 100 mg/dL for patients with pre existing cardiovascular disease is desirable. Secondary lipid management program goals include: (1) collecting, storing, and analyzing patient demographics; (2) implementing programs involving lifestyle modification, smoking cessation, weight control; and (3) measuring clinical and economic outcomes. Convergence of several driving forces in managing hypercholesterolemia provides cardiologists with the ability to improve the process. These forces include: market-consolidated delivery systems, established lipid management guidelines, and employer-initiated policies requiring higher quality care within managed-care organizations. Methods to achieve enhanced treatment effectiveness, patient satisfaction, and control costs are discussed. Utilizing multidisciplinary teams including nurse case managers, clinical pharmacists, dietitians, and physician assistants to achieve lipid level goals and for nutritional counseling is desirable. Developing disease state management programs, treatment algorithms, databases with analytic reports, and process improvement across the network is of paramount importance for future progress and success. PMID- 9373001 TI - Improving care with nurse case managers: practical aspects of designing lipid clinics. AB - Compliance with the National Cholesterol Education Program (NCEP II) Adult Treatment Panel II guidelines for lipid management in patients with coronary artery disease has not been widespread. Barriers to effective lipid management occur at numerous levels of interaction between the patient, provider, and healthcare organizations. Nurse care managers (NCMs), recognized in the inpatient and discharge planning settings, are emerging in new roles in the outpatient setting working in subspecialty areas including lipid/risk-reduction, heart failure, and anticoagulation clinics. To improve patient adherence to NCEP II goals, NCMs can help overcome treatment barriers by: (1) bridging inpatient/outpatient care; (2) securing long-term patient compliance and follow up; (3) developing clinic policy and computerized patient databases; (4) implementing management algorithms; and (5) enhancing financial reimbursement from insurers. Additional graduate nursing programs and novel healthcare delivery models demonstrating the ability to overcome the barriers to improved patient care must be encouraged and supported. PMID- 9373002 TI - Rehabilitation of the coronary artery disease patient: capturing patients. PMID- 9373003 TI - Comprehensive cardiovascular disease risk reduction in a cardiac rehabilitation setting. AB - Cardiac rehabilitation combines prescriptive exercise training with coronary artery disease (CAD) risk factor modification in patients with established CAD. As such, cardiac rehabilitation programs are ideally positioned to assume a pivotal role in the rendering of many components of comprehensive cardiovascular disease risk reduction in a secondary prevention setting. However, the extent to which traditional cardiac rehabilitation programs can successfully accomplish this goal is limited by low participation rates, inadequate emphasis on many of the essential aspects of secondary prevention, and lack of long-term follow-up of patients. To overcome these deficiencies, cardiac rehabilitation programs should evolve into cardiovascular risk reduction programs by implementing approaches that have been shown to be effective in randomized clinical trials. In this manuscript we describe one such approach, based on the Stanford Coronary Risk Intervention Project, which has been implemented in > 1,000 patients. Key components of this physician-supervised, nurse case-manager model include: (1) initial evaluation and risk assessment; (2) identification of specific goals for each CAD risk factor; (3) formulation and implementation of an individualized treatment plan that includes lifestyle modification and pharmacologic interventions for accomplishing specific risk reduction goals; (4) long-term follow-up to enhance compliance and revise the treatment plan as indicated; and (5) a mechanism for outcomes based long-term assessment of each patient. PMID- 9373004 TI - Legal and policy considerations in using clinical practice guidelines. AB - The increased use of clinical practice guidelines has implications for both public policy and for litigation. Physicians are concerned that the introduction of practice guidelines will reduce their clinical decision-making authority and that the failure to follow clinical practice guidelines will lead to medical liability. Although practice guidelines are an increasing part of medical practice, there has been only limited litigation to determine the extent to which guidelines will be used to set the applicable standard of care. This article discusses the potential legal and public policy issues raised by the introduction and use of clinical practice guidelines. From a legal perspective, the primary issue is whether guidelines will be used to set the "standard of care" or will be one piece of evidence that a jury would use to determine the outcome of medical liability litigation. Based on an assessment of the applicable legal and policy considerations, the article concludes that courts should admit guidelines into evidence, but that they should not be used as the sole determinant of the standard of care. Instead, guidelines should be treated as one piece of evidence to be weighed by the jury. This approach will facilitate physician acceptance of guidelines by not imposing liability for the failure to follow guidelines without additional evidence to determine the standard of care. PMID- 9373005 TI - Improving care for unstable angina patients in a multiple hospital project sponsored by a federally designated quality improvement organization. AB - In 1992, the Health Care Financing Administration (HCFA) implemented a major change in the methodology of the quality of care oversight activities conducted by Medicare Peer Review Organizations. The Health Care Quality Improvement Program (HCQIP) represented a shift in oversight activity direction from identifying and dealing with individual clinical errors to helping providers improve mainstream care. The change in the oversight activities of Peer Review Organizations has been so substantial that the organizations are now commonly referred to as Quality Improvement Organizations (QIOs). Since its introduction, the HCQIP has developed multiple cooperative projects between QIOs and participating hospitals to examine specific processes of care and to ultimately improve the quality of care provided to Medicare patients. This report describes one project in North Carolina focusing on inpatient treatment of patients with a principal diagnosis of unstable angina, one of the most frequent causes of hospital admissions for Medicare patients. Based on the guidelines for treating unstable angina issued by the Agency for Health Care Policy and Research, 5 measures of good medical care for these patients were selected as quality of care indicators. A total of 16 hospitals in North Carolina each provided medical records of approximately 50 Medicare patients discharged with a principal diagnosis of unstable angina. Our findings indicated that guidelines-recommended standard of care were met in only a minority of patients. These indicators of care--including ordering an electrocardiogram within the first hour of admission and admitting high-risk patients to the intensive care unit--all occurred in <50% of the patients. Moreover, use of drugs that improve outcomes in patients with unstable angina was lower than expected. Only 17% of eligible patients with unstable angina were discharged on a lipid-lowering medication. Although there was variation in compliance with the guidelines between types of hospitals, all hospitals had an opportunity to improve in at least one quality of care indicator. The data demonstrate that significant variances exist between published guidelines and actual practices. Given the high rates of readmission for patients with coronary disease, there is opportunity to improve compliance with recommended guidelines of good care. The new oversight activity direction taken by Medicare should ultimately improve care for more patients than could ever be achieved through individual case review. PMID- 9373007 TI - Symposium summary remarks. PMID- 9373006 TI - Dyslipidemia treatment guidelines and management systems in Kaiser Permanente. AB - Coronary artery disease (CAD) remains the leading cause of morbidity and mortality in the United States. Although risk factors contributing to the development of this disease are well known and effective interventions exist, the majority of patients eligible for pharmacotherapy are inadequately treated or not treated at all. Multiple factors contribute to this treatment gap. With respect to dyslipidemia, 2 of the major challenges facing healthcare organizations are: (1) how to ensure continued monitoring and medication adherence for patients with known atherosclerosis (secondary prevention); and (2) how to select the high-risk patients who will most benefit from treatment from the larger population of individuals who have not had a known coronary event (primary prevention). In Southern California Kaiser Permanente, 2 approaches being used to address these issues are dyslipidemia treatment guidelines and a computerized monitoring system. The guidelines stratify patients based on CAD risk and expected benefit from drug therapy. The computerized monitoring incorporates an "expert system" algorithm that facilitates patient selection in primary prevention and tracking to encourage patient compliance. This article describes these 2 approaches that attempt to maximize the effectiveness and efficiency of dyslipidemia management. PMID- 9373008 TI - Developmental expression, pattern of distribution, and effect on cell aggregation implicate a neuron-glial junctional domain protein in neuronal migration. AB - We developed a panel of monoclonal antibodies to cerebellar astroglial cells and selected for study those that revealed microdomain structures on the cell surface of neocortical and cerebellar astrocytes. One antibody, 15D7-AD7, recognized the approximately 72 kDa polypeptide doublet that was identified previously by the polyclonal antibody D4 as a component of the microdomain structure formed between migrating neurons and radial glial cell processes (Cameron and Rakic [1994] J. Neurosci. 14:3139-3155). Immunofluorescent localization studies reveal a spatial and temporal pattern of 15D7 immunoreactivity in multiple brain regions that correlates well with time periods when neuronal cell migration is a prominent morphogenetic event. In areas where the process of migration is underway, 15D7 immunoreactivity is detected simultaneously in both radial glial cells and cells that have the positional and morphologic features characteristic of migrating neurons. Subsequent to the completion of migration, immunoreactivity is detected in the transitional forms of radial glial cells and mature astrocytes, but not in neurons. Cell aggregation analyses reveal that 15D7 antibodies perturb the rate of aggregation for astrocyte-astrocyte, neuron-neuron, and mixed cell-cell combinations. Taken together, the present studies suggest that the polypeptides recognized by the 15D7 antibodies likely participate in an adhesive process, principally within the ventricular and subventricular zones, that is essential at the onset of the cell migration process. PMID- 9373009 TI - Overexpression of nerve growth factor in skin causes preferential increases among innervation to specific sensory targets. AB - The impact of increased levels of skin-derived nerve growth factor (NGF) neurotrophin on sensory and sympathetic innervation to the mouse mystacial pad and postero-orbital vibrissae was determined. Consistent with an approximate doubling of neuron number in trigeminal and superior cervical ganglia, many components of the sensory and sympathetic innervation were substantially enhanced. Although the increased number of neurons raised the possibility that all types of innervation were increased, immunohistochemical analysis indicated that enhanced NGF production had a differential effect upon sensory innervation, primarily increasing unmyelinated innervation. This increased innervation occurred in specific locations known to be innervated by small, unmyelinated fibers, suggesting that NGF modulated sensory innervation density, but not targeting. In contrast, sympathetic innervation was not only increased but also was distributed to some aberrant locations. In the intervibrissal fur of the mystacial pad, both the number of sensory axons and branches appeared increased, whereas in vibrissal follicle sinus complexes, only branching increased. In some areas, sensory ending density was lower than expected based upon the size of the source nerve bundles suggesting that many axons and branches were surviving but failing to form functional endings. Furthermore, the immunochemical profile of innervation was altered in some sensory populations as demonstrated by the coexistence of RT-97 neurofilament labeling in calcitonin gene-related peptide (CGRP) positive axons, by the loss of substance P colocalization in some CGRP axons, and by an absence of neuropeptide Y labeling in tyrosine hydroxylase positive sympathetic axons. Collectively, these results indicate that the NGF mediated increase in neuron number may be selective for particular sets of innervation and that increases among some populations may result from phenotypic switching. PMID- 9373010 TI - Development of commissural neurons in the wallaby (Macropus eugenii). AB - We have examined the development of the laminar and areal distribution of cortical commissural neurons in a marsupial mammal, the wallaby Macropus eugenii. In this species, commissural axons approach the major cerebral commissure, the anterior commissure, via either the internal capsule or the external capsule and first cross the midline at postnatal day 14 (P14). By retrogradely labelling these axons with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine (DiI) at P15, we show here that the cell bodies of these neurons are restricted to a region of cortex adjacent to the rhinal fissure. Most of these labelled neurons are located in the compact cell zone of the cortical plate, with only a few labelled cells found in the zone of loosely packed cells deep to this layer. Over the subsequent 66 days, commissural neurons are found progressively more dorsally, rostrally, and caudally, so that, by P80, they are present throughout the extent of the neocortex. At this age, they are mainly pyramidal in morphology and form a single band within the deeper part of layer 5 of the developing cortex. From P80 to adulthood, the distribution of commissural neurons has been assessed in the visual cortex by using retrograde transport of horseradish peroxidase. At P80, labelled neurons with immature pyramidal morphology are present throughout the occipital cortex; as in DiI material, somata are located in deep layer 5. At P165, previously shown to be the age when commissural axon numbers peak, widespread labelling is present in the occipital region, with labelled cells now found in two bands corresponding to layers 3 and 5. After this age, neurons become more restricted in distribution, so that, by adulthood, commissural neurons are no longer apparent throughout area 17 but are restricted to a localised region around the area 17/18 boundary. Within this region, labelling is still present in layers 3 and 5 but is more dense in layer 3. The gradual restriction of commissural fields seen here in the wallaby is similar to that reported in the neocortex in many eutherians. These findings also support studies in eutheria, suggesting that subplate neurons do not appear to play a major role in commissural development. PMID- 9373011 TI - Identification of C1 presympathetic neurons in rat rostral ventrolateral medulla by juxtacellular labeling in vivo. AB - The rostral ventrolateral medulla (RVLM) contains barosensitive, bulbospinal neurons that provide the main supraspinal excitatory input to sympathetic vasomotor preganglionic neurons. However, the phenotype of the critical RVLM cells has not been conclusively determined. The goal of the current study was to identify the proportion of electrophysiologically defined, putative, presympathetic RVLM neurons that are C1 cells. We used a juxtacellular labeling technique to individually fill spontaneously active, barosensitive, bulbospinal RVLM neurons with biotinamide following electrophysiological characterization in chloralose-anesthetized rats. To determine whether these neurons could be classified as C1 cells, the biotinamide-labeled cells were processed for detection of tyrosine hydroxylase. The majority of barosensitive bulbospinal RVLM neurons were tyrosine hydroxylase immunoreactive (TH-ir; 28 of 39). All of the barosensitive bulbospinal RVLM neurons with axonal conduction velocities in the C fiber range (<1 m/second) were TH-ir (n = 16), whereas faster conducting cells (1 to 7 m/second) were either lightly TH-ir (n = 12) or not detectably TH-ir (n = 11). Adjacent respiratory-related RVLM units labeled with biotinamide were not detectably TH-ir (n = 10). To verify that TH-ir cells were indeed adrenergic, a subset of barosensitive bulbospinal cells labeled with biotinamide were examined for phenylethanolamine N-methyltransferase immunoreactivity (PNMT-ir). Three slowly conducting cells had detectable PNMT-ir, and two fast-conducting cells had no detectable PNMT-ir. These results indicate that the majority of bulbospinal RVLM neurons with putative sympathoexcitatory function are C1 cells. PMID- 9373013 TI - The second visual area in the marmoset monkey: visuotopic organisation, magnification factors, architectonical boundaries, and modularity. AB - The organisation of the second visual area (V2) in marmoset monkeys was studied by means of extracellular recordings of responses to visual stimulation and examination of myelin- and cytochrome oxidase-stained sections. Area V2 forms a continuous cortical belt of variable width (1-2 mm adjacent to the foveal representation of V1, and 3-3.5 mm near the midline and on the tentorial surface) bordering V1 on the lateral, dorsal, medial, and tentorial surfaces of the occipital lobe. The total surface area of V2 is approximately 100 mm2, or about 50% of the surface area of V1 in the same individuals. In each hemisphere, the receptive fields of V2 neurones cover the entire contralateral visual hemifield, forming an ordered visuotopic representation. As in other simians, the dorsal and ventral halves of V2 represent the lower and upper contralateral quadrants, respectively, with little invasion of the ipsilateral hemifield. The representation of the vertical meridian forms the caudal border of V2, with V1, whereas a field discontinuity approximately coincident with the horizontal meridian forms the rostral border of V2, with other visually responsive areas. The bridge of cortex connecting dorsal and ventral V2 contains neurones with receptive fields centred within 1 degree of the centre of the fovea. The visuotopy, size, shape and location of V2 show little variation among individuals. Analysis of cortical magnification factor (CMF) revealed that the V2 map of the visual field is highly anisotropic: for any given eccentricity, the CMF is approximately twice as large in the dimension parallel to the V1/V2 border as it is perpendicular to this border. Moreover, comparison of V2 and V1 in the same individuals demonstrated that the representation of the central visual field is emphasised in V2, relative to V1. Approximately half of the surface area of V2 is dedicated to the representation of the central 5 degrees of the visual field. Calculations based on the CMF, receptive field scatter, and receptive field size revealed that the point-image size measured parallel to the V1/V2 border (2-3 mm) equals the width of a full cycle of cytochrome oxidase stripes in V2, suggesting a close correspondence between physiological and anatomical estimates of the dimensions of modular components in this area. PMID- 9373012 TI - Interactions between glial progenitors and blood vessels during early postnatal corticogenesis: blood vessel contact represents an early stage of astrocyte differentiation. AB - The post-neurogenic period in the mammalian neocortex is characterized by the growth of astrocyte and oligodendrocyte populations and their incorporation into the network of the developing central nervous system (CNS). Many of these glial cells originate as progenitors in the subventricular zone (SVZ) and then migrate into white and gray matter before differentiating. What determines the specific cellular fate of progenitors in vivo is not known, however. In examining the early stages of gliogenesis from progenitors in the SVZ, we noted that interactions with cortical blood vessels took place at what appeared to be an early stage of glial differentiation. We have examined in more detail the interactions of progenitors with blood vessels in the early postnatal rat neocortex after labeling progenitors in vivo with a LacZ-encoding retrovirus. These early interactions are accompanied by an increase in intermediate filament expression, consistent with astrocytic differentiation. Because astrocytes interact with blood vessels and pia, we suggest that such contact represents an early stage in astrocytic differentiation. Furthermore, since angiogenesis and astrogenesis occur over a similar period, the growth of blood vessels may even play a role in the selection of astrocytic fate by a progenitor. As vessel growth slows, fewer progenitors may be directed toward an astrocyte fate, allowing more to differentiate into oligodendrocytes, perhaps explaining the shift from astrocyte genesis to oligodendrocyte genesis during early postnatal cortical development. PMID- 9373014 TI - Disinhibition of the superior colliculus restores orienting to visual stimuli in the hemianopic field of the cat. AB - Following unilateral removal of all known visual cortical areas, a cat is rendered hemianopic in the contralateral visual field. Visual orientation can be restored to the blind hemifield by transection of the commissure of the superior colliculus or by destruction of the superior colliculus (SC) or the substantia nigra pars reticulata (SNpr) contralateral to the cortical lesion. It is hypothesized that a mechanism mediating recovery is disinhibition of the SC ipsilateral to the cortical lesion. The ipsilateral nigrotectal projection exerts a robust inhibitory tone onto cells in the SC. However, ibotenic acid destruction of SNpr neurons, which should decrease inhibition onto the SC, does not result in recovery. The failure of ipsilateral SNpr lesions to produce recovery puts into question the validity of SC disinhibition as a mechanism of recovery. We directly tested the disinhibition hypothesis by reversibly disinhibiting the SC ipsilateral to a visual cortical lesion with a gamma-aminobutyric acid (GABA)A antagonist, bicuculline methiodide. In accordance with the hypothesis, transient disinhibition of the SC restored visual orienting for several hours in three of eight animals. Recovery was not a volume or pH effect and was distinct from the release of irrepressible motor effects (i.e., approach and avoidance behaviors) seen within the first hour after injection. Thus, in the absence of all visual cortical areas unilaterally, disinhibition of the SC can transiently restore the ability of the cat to orient to visual stimuli in the previously "blind" hemifield. PMID- 9373015 TI - Multiarchitectonic and stereotactic atlas of the human thalamus. AB - To improve anatomical definition and stereotactic precision of thalamic targets in neurosurgical treatments of chronic functional disorders, a new atlas of the human thalamus has been developed. This atlas is based on multiarchitectonic parcellation in sections parallel or perpendicular to the standard intercommissural reference plane. The calcium-binding proteins parvalbumin (PV), calbindin D-28K (CB), and calretinin (CR) were used as neurochemical markers to further characterize thalamic nuclei and delimit subterritories of functional significance for stereotactic explorations. Their overall distribution reveals a subcompartmentalization of thalamic nuclei into several groups. Predominant PV immunostaining characterizes primary somatosensory, visual and auditory nuclei, the ventral lateral posterior nucleus, reticular nucleus (R), and to a lesser degree also, lateral part of the centre median nucleus, and anterior, lateral, and inferior divisions of the pulvinar complex. In contrast, CB immunoreactivity is prevalent in medial thalamic nuclei (intralaminar and midline), the posterior complex, ventral posterior inferior nucleus, the ventral lateral anterior nucleus, ventral anterior, and ventral medial nuclei. The complementary distributions of PV and CB appear to correlate with distinct lemniscal and spinothalamic somatosensory pathways and to cerebellar and pallidal motor territories, respectively. Calretinin, while overlapping with CB in medial thalamic territories, is also expressed in R and limbic associated anterior group nuclei that contain little or no CB. Preliminary analysis indicates that interindividual nuclear variations cannot easily be taken into account by standardization procedures. Nevertheless, some corrections in antero-posterior coordinates in relation to different intercommissural distances are proposed. PMID- 9373016 TI - Morphology and sensory modality of mushroom body extrinsic neurons in the brain of the cockroach, Periplaneta americana. AB - Mushroom bodies are paired centers in insect brains that are thought to be crucial in olfactory learning and memory. Early neuroanatomical descriptions suggested that the mushroom bodies comprise rather simple arrangements of nerve cells. Intrinsic neurons within each mushroom body were believed to receive olfactory afferents and to supply long, branched axons to extrinsic neurons that lead from the mushroom body into the protocerebrum. More recent suggestions that the mushroom bodies integrate several sensory modalities find support from intracellular and extracellular recordings of extrinsic neurons in the brains of crickets, honey bees, and cockroaches. Here, we describe two major classes of extrinsic neurons, simple and complex cells, in the mushroom bodies of the cockroach Periplaneta americana. Each class is defined by its pattern of branching in the brain. Simple neurons correspond to extrinsic neurons described from other species that have one set of dendrites only within the mushroom bodies. Complex extrinsic neurons possess dendrite-like branches within and outside the mushroom bodies. This arrangement may account in part for their observed multimodality, as might newly identified afferent neurons that terminate in the mushroom body lobes among the dendrites of extrinsic neurons and that respond to multimodal stimuli. Organizational complexity within the mushroom bodies is suggested by the grouping of intrinsic cell axons into discrete laminae. These are intersected by the block-like arrangements of dendritic fields of extrinsic neurons in a manner reminiscent of Purkinje cell dendrites intersecting parallel fibers in the cerebellum. The present results demonstrate that the cockroach mushroom body processes multimodal sensory information and that its neural arrangements contribute to a precise architecture consisting of discrete longitudinal and transverse subdivisions. PMID- 9373017 TI - Orientation-specific relationship between populations of excitatory and inhibitory lateral connections in the visual cortex of the cat. AB - The topography of lateral excitatory and lateral inhibitory connections was studied in relation to orientation maps obtained in areas 17 and 18. Small iontophoretic injections of biocytin were delivered to the superficial layers in regions where orientation selectivity had been mapped using electrode recordings of single- and multi-unit activity from various cortical depths. Biocytin revealed extensive patchy axonal projections of up to 3.5 mm in both areas while labelled somata occurred chiefly at the injection site, indicating that the labelling was primarily anterograde. Two types of boutons could be clearly distinguished: (i) putative excitatory boutons either en passant or having a short stalk and (ii) inhibitory boutons which were invariably of the basket-type. Three-dimensional reconstructions of all labelled boutons showed that the excitatory and the inhibitory networks had a distinctively different relationship to orientation maps. The overall distribution of connections showed that 53-59% of excitatory and 46-48% of inhibitory connections were at iso-orientation, +/-30 degrees; oblique-orientation, +/-(30-60) degrees, was shown by 30% of excitatory and 28-39% of inhibitory connections; cross-orientation was shown by 11-17% of excitatory and 15-24% of inhibitory connections. Although excitatory patches occupied mainly iso-orientation locations, interpatch regions representing chiefly non-iso-orientations (oblique + cross orientation) were also innervated. There was considerable overlap between the excitatory and inhibitory network. Nonetheless, inhibitory connections were more common than excitatory connections with non-iso-orientation locations. There was no significant difference between the orientation topography of area 17 and area 18 projections. The results suggest that in general the lateral connectivity system is not orientation specific, but shows a moderate iso-orientation preference for excitation and an even weaker iso-orientation preference for inhibition. The broad orientation spectrum of lateral connections could provide the basis for mechanisms that requiring different orientations, as for example in detecting orientation discontinuities. PMID- 9373018 TI - Inhibitory synaptogenesis in mouse somatosensory cortex. AB - It is widely believed that inhibitory synapses are not present or present in only small numbers in the rodent cerebral cortex during the early postnatal period when the cortex is being innervated by thalamocortical fibers. Quantitative electron microscopy was carried out on the posteromedial barrel subfield of mouse somatosensory cortex from postnatal day 4 (P4) when thalamocortical innervation of the barrels is becoming established, through to sexual maturity (>P32), and in adulthood. Both asymmetrical (putatively excitatory) and symmetrical (putatively inhibitory) synapses were present in all layers from P4. The symmetrical synapses were immunoreactive for GABA at all ages. There was a progressive increase in both asymmetrical and symmetrical synapses up to P32, density in all layers increasing 16-fold, with the production of asymmetrical synapses leading and greatly outstripping that of symmetrical. From P32 to P120, the oldest age studied, synaptic numbers declined by 18% to 13 times the P4 level, but this affected predominantly layers II/III, IV and V, and mainly involved asymmetrical synapses. The relative percentage of asymmetrical to symmetrical synapses from P4 to P8 was 57%/43% but at P32 it was 89.5%/10.5% and in adulthood 85.4%/14.6%. These data indicate that inhibitory synaptogenesis in the rodent cortex begins earlier than previously thought, a basis for inhibition being present from the earliest period. Pruning of all synapses occurs well after thalamocortical innervation is established and inhibitory synapses are less affected by the pruning process. PMID- 9373020 TI - Modulation of responses to optic flow in area 7a by retinotopic and oculomotor cues in monkey. AB - Perception of two- and three-dimensional optic flow critically depends upon extrastriate cortices that are part of the 'dorsal stream' for visual processing. Neurons in area 7a, a sub-region of the posterior parietal cortex, have a dual sensitivity to visual input and to eye position. The sensitivity and selectivity of area 7a neurons to three sensory cues - optic flow, retinotopic stimulus position and eye position - were studied. The visual response to optic flow was modulated by the retinotopic stimulus position and by the eye position in the orbit. The position dependence of the retinal and eye position modulation (i.e. gain field) were quantified by a quadratic regression model that allowed for linear or peaked receptive fields. A local maximum (or minimum) in both the retinotopic fields and the gain fields was observed, suggesting that these sensory qualities are not necessarily linearly represented in area 7a. Neurons were also found that simply encoded the eye position in the absence of optic flow. The spatial tuning for the eye position signals upon stationary stimuli and optic flow was not the same, suggesting multiple anatomical sources of the signals. These neurons can provide a substrate for spatial representation while primates move in the environment. PMID- 9373019 TI - Cortical structure predicts the pattern of corticocortical connections. AB - Cortical areas are linked through pathways which originate and terminate in specific layers. The factors underlying which layers are involved in specific connections are not well understood. Here we tested whether cortical structure can predict the pattern as well as the relative distribution of projection neurons and axonal terminals in cortical layers, studied with retrograde and anterograde tracers. We used the prefrontal cortices in the rhesus monkey as a model system because their laminar organization varies systematically, ranging from areas that have only three identifiable layers, to those that have six layers. We rated each prefrontal area based on the number and definition of its cortical layers (level 1, lowest; level 5, highest). The structural model accurately predicted the laminar pattern of connections in approximately 80% of the cases. Thus, projection neurons from a higher-level cortex originated mostly in the upper layers and their axons terminated predominantly in the deep layers (4-6) of a lower-level cortex. Conversely, most projection neurons from a lower level area originated in the deep layers and their axons terminated predominantly in the upper layers (1-3) of a higher-level area. In addition, the structural model accurately predicted that the proportion of projection neurons or axonal terminals in the upper to the deep layers would vary as a function of the number of levels between the connected cortices. The power of this structural model lies in its potential to predict patterns of connections in the human cortex, where invasive procedures are precluded. PMID- 9373021 TI - The spatial distribution of the antagonistic surround of MT/V5 neurons. AB - The majority (217/325, 66%) of the neurons in the middle temporal (MT) area/V5 show strong antagonistic surrounds, defined here by a decrease of at least 50% in the summation curve. We mapped the antagonistic surround in 145 such cells, using eight circularly distributed surround stimulus patches (Surround Asymmetry Test, SAT) and also mapped the surround in 51 of these 145 cells using a grid consisting of 25 square patches (Surround Mapping Test, SMT). Both tests showed that the angular surround distribution was non-uniform in the majority of these neurons. In half the neurons, the antagonistic surround was asymmetric, and arose from a single region on one side of the excitatory receptive field (ERF). In another quarter of the sample the surround was bilaterally symmetric, and arose from a pair of regions on opposite sides of the ERF. Only the remaining 20% showed a circularly symmetric surround distribution. These three groups differed in their laminar distribution. The SMT showed that, radially, the surround antagonism reached a maximum, on average, at 1.5 times the ERF radius. Detailed comparisons of the spatial relationships of excitatory and inhibitory regions of the RF components shows that non-homogeneity of the surround influence appears to be an intrinsic property of the surround. Such a property may underly the extraction of the surface orientation and curvature from speed patterns. PMID- 9373023 TI - The kinetic occipital (KO) region in man: an fMRI study. AB - We used functional magnetic resonance imaging to explore, in individual subjects, the properties of the kinetic occipital (KO) region, which previous position emission tomography studies have shown to be involved in the processing of kinetic boundaries. The KO region was significantly activated in 23/25 subjects tested in the subtraction of uniform motion from kinetic gratings. The KO region is genuinely specialized for processing kinetic boundaries since it is significantly more activated by kinetic gratings than by luminance-defined gratings, uniform motion or transparent motion. This leaves only the kinetic boundaries, created by discontinuities in motion direction, as the specific stimulus aspect, activating the KO region. The KO region is anatomically and functionally distinct from areas MT/V5, V3 and V3A. It also has minimal overlap with the lateral occipital (LO) region. The selective activation of the KO region is robust and relatively immune to changes in stimulus size, spatial frequency and type of kinetic boundary. These results strongly argue for the view that the KO region is a new, separate, functional region in human occipital cortex. PMID- 9373022 TI - A gradient in the duration of the G1 phase in the murine neocortical proliferative epithelium. AB - Neuronogenesis in the neocortical pseudostratified ventricular epithelium (PVE) is initiated rostrolaterally and progresses caudo-medially as development progresses. Here we have measured the cytokinetic parameters and the fractional neuronal output parameter, Q, of laterally located early-maturing regions over the principal embryonic days (E12-E15) of neocortical neuronogenesis in the mouse. These measures are compared with ones previously made of a medial, late maturing portion of the PVE. Laterally, as medially, the duration of the neuronogenetic interval is 6 days and comprises 11 integer cell cycles. Also, in both lateral and medial areas the length of G1 phase (TG1) increases nearly 4 fold and is the only cell cycle parameter to change. Q progresses essentially identically laterally and medially with respect to the succession of integer cell cycles. Most importantly, from E12 to E13 there is a steeply declining lateral to medial gradient in TG1. The gradient is due both to the lateral to medial graded stage of neuronogenesis and to the stepwise increase in TG1 with each integer cycle during the neuronogenetic interval. To our knowledge this gradient in TG1 of the cerebral PVE is the first cell biological gradient to be demonstrated experimentally in such an extensive proliferative epithelial sheet. We suggest that this gradient in TG1 is the cellular mechanism for positionally encoding a protomap of the neocortex within the PVE. PMID- 9373024 TI - Dorsoventral patterning and oligodendroglial specification in the developing central nervous system. AB - While the bulk of oligodendendrocytes are generated postnatally in rodents, it is now clear that the first oligodendrocytes are born during midembryonic development. Recent studies imply that the first oligodendrocytes to appear are specified concurrently with certain neuronal subtypes. In addition, patterning molecules known to confer positional information on neural tissues during development, such as sonic hedgehog and bone morphogenetic proteins, have also been implicated in the specification of glial fate. This review discusses some of the recent advances in our knowledge of how oligodendrocytes are generated and the mechanisms by which this might occur in the developing brain and spinal cord. PMID- 9373026 TI - Spinal cord oligodendrocytes develop from a limited number of migratory highly proliferative precursors. AB - Oligodendrocytes are responsible for myelin formation in spinal cord white matter. In the mature spinal cord, the majority of white matter is localized peripherally. During early development, however, the first oligodendrocyte precursors arise in the ventral ventricular zone of the developing cord. Thus, prior to myelination, both migration and proliferation of oligodendrocyte precursors must occur. When and where these events occur is currently unclear. In the chick spinal cord, oligodendrocyte precursors express antigens recognized by the monoclonal antibody O4. Here we show that all chick spinal cord oligodendrocytes are derived from O4+ cells and all O4+ cells appear to give rise to oligodendrocytes. Analysis of the number and distribution of oligodendrocyte precursors in chick spinal cord at different stages of development suggests that relatively few cells migrate from the ventricular source which then proliferate extensively in white matter. This migration is guided by general dispersive cues. Clonal analysis of oligodendrocyte development in cultures derived from different regions of the rodent spinal cord indicated that the cells that initially populate dorsal and peripheral spinal cord retained similar clonal properties to those in ventral spinal cord, suggesting the migrating cells were immature, highly proliferative precursors. Consistent with these results, BrdU incorporation studies indicate that glial proliferation is extensive and persistent in postnatal rat spinal cord white matter. Together, these studies suggest that spinal cord white matter is initially populated by very immature precursors that then undergo extensive local proliferation prior to myelination. PMID- 9373025 TI - Emergence of oligodendrocytes from human neural spheres. AB - To study the development of human oligodendrocyte precursors (OP), we expanded human embryonic brain-derived neural precursors into spheres with basic fibroblast growth factor (FGF2). Over 90% of the cells in the expanded spheres were precursors coexpressing nestin and the polysialylated (PSA) form of NCAM. The remaining cells were mostly astrocytes and neuronal cells located at the periphery of the floating spheres. When spheres were allowed to adhere on fibronectin-coated substrate in the absence of FGF2, neural precursors migrated in the outgrowth and often formed chains of cells expressing high levels of PSA NCAM. Many migrating cells also expressed beta-3 tubulin while only scattered elongated cells radiating from the spheres were GFAP+ astrocytes. Spindle-shaped cells not associated with the chains were labeled for the PDGF-alpha receptor and often coexpressed MAP2 neuronal isoforms. Neuronal cells in the outgrowth rapidly established a rich neuritic network where OP expressing O4 and DM20/proteolipid antigens appeared. T3 treatment of neural spheres increased the rate of OP formation and the complexity of their shape. Thus, the generation of human oligodendrocytes from neural precursors is tightly correlated with growth of neuronal processes and enhanced by hormonal signals. PMID- 9373027 TI - Oligodendrocyte maturation in Xenopus laevis. AB - Oligodendrocytes, the myelinating cells of the central nervous system, have a characteristic morphology, whose full extent is revealed immunohistochemically by the expression of specific markers. Proteolipid protein (PLP) is regarded as a terminal differentiation marker of oligodendrocytes. By using PLP antibody and confocal microscopy, PLP expression in developing oligodendrocytes and the detailed three-dimensional morphology of oligodendrocytes were observed throughout early and late Xenopus laevis tadpole development. Premyelinating oligodendrocytes with radial processes were intensely stained with PLP antibody. The morphology of developing oligodendrocytes is comparable with that described in rodents. In Xenopus, the appearance of PLP- and MBP-positive oligodendrocytes is synchronized spatially and temporarily, revealing that PLP is also an early marker of developing oligodendrocytes. In addition, oligodendrocytes in early tadpole spinal cord are few in number but have a large cell body that is easily identified on a transverse section, revealing the relatively simple cytoarchitecture of this glial component. Xenopus spinal cord may therefore be useful as model system for studying the maturation of oligodendrocytes and the myelination process in situ. PMID- 9373028 TI - In vitro death of jimpy oligodendrocytes: correlation with onset of DM-20/PLP expression and resistance to oligodendrogliotrophic factors. AB - Severe hypomyelination in the jimpy (jp) mouse mutation results from premature death of most oligodendrocytes (OCs). We have applied an immunopanning technique to successfully purify oligodendroblasts (OBs) directly from neonatal jp brainstem in order to determine if their death during differentiation into OCs is preventable in culture by diffusible oligodendrogliotrophic factors. No significant differences in the yield (0.9-1.1 x 10(5) cells/brainstem) or viability (approximately 90%) of OB populations from jp and wild-type (wt) littermates were observed, indicating that cell death occurs at a later stage in the mutant lineage. When cultured in a basally defined, insulin-containing medium, wt and jp OBs died 1-2 days later as their differentiation into GalC+ OCs began. Survival was not enhanced by known trophic factors (ciliary neurotrophic factor, leukemia inhibitory factor, neurotrophin-3) for differentiating rat OCs. In medium conditioned by neonatally derived rat or wt mouse astrocytes, however, wt OBs survived terminal OC differentiation, expressing first GalC, then DM 20/PLP on their surface 1-2 days later, before elaborating myelin-like membrane. By contrast, jp OBs in sister cultures survived differentiation initially as well as their normal counterparts did but rapidly died thereafter, beginning at the time when PLP/DM-20 immunoreactivity became detectable on premature wt GalC+ OCs. Additionally under these conditions, there survived a minor population (<5%) of jp cells, including mature OCs, which expressed stunted membranes and DM-20/PLP immunoreactivity in their cytoplasm, and undifferentiated progenitors. This model supports the concept that OC death in jp is effected by an intrinsic program, one mechanistically related to jp PLP/DM-20 gene expression and refractory to trophic cues in the environment. PMID- 9373029 TI - In situ expression of PLP/DM-20, MBP, and CNP during embryonic and postnatal development of the jimpy mutant and of transgenic mice overexpressing PLP. AB - We analyzed by in situ hybridization the spatiotemporal expression of dm-20, myelin basic protein (MBP) and 2'-3' cyclic nucleotide phosphodiesterase (CNP) during embryonic and postnatal development of the normal mouse and two plp/dm-20 mutants: the jimpy mouse and a transgenic mouse overexpressing the plp gene. In the central nervous system (CNS) of the normal mouse, dm-20 mRNA was detected at embryonic day (E)9.5 in the laterobasal plate of the diencephalon. The pattern of expression of CNP transcript was superimposable on that of dm-20, but appeared slightly later, at E12.5. MBP mRNA was detected even later (E14.5), and, in addition, only in the caudal (rhombencephalon and spinal cord) territories of expression of dm-20 and CNP. These observations support our previous proposals: (1) dm-20-expressing cells in the germinative neuroepithelium are precursors of oligodendrocytes, and (2) oligodendrocytes emerge from distinct pools of precursors along the neural tube (Timsit et al., 1995). In the jimpy mutant, despite the mutation in the plp gene, cells of the oligodendrocyte lineage developed normally. It is only at the time of myelin deposition that oligodendrocytes die. During embryonic development of the transgenic mutant overexpressing plp, there were no alterations in the spatiotemporal pattern or the level of expression of dm-20 in the CNS, in contrast to the higher levels of dm-20 observed in the peripheral nervous system (PNS). PMID- 9373030 TI - Expression and function of thrombospondin-1 in myelinating glial cells of the central nervous system. AB - The thrombospondin (TSP) family of extracellular matrix glycoproteins are widely expressed in the developing and adult central nervous system although their function remains poorly defined. We have used cell culture techniques to analyse the expression and function of TSPs in glial cells derived from myelinated regions of the central nervous system. These experiments show that TSP-1 mRNA, but not TSP-2 or TSP-3 mRNA, is expressed by astrocytes from these regions. TSP-1 mRNA levels in astrocytes are under the regulation of growth factors, being increased by TGFbeta1 and decreased by bFGF. Oligodendrocyte precursors do not express TSP-1, TSP-2, or TSP-3 mRNA. Migration of oligodendrocyte precursor cells is stimulated by TSP-1 substrates as measured either by time-lapse microscopy or using a microchemotaxis chamber assay. Taken together, these results suggest that the extracellular matrix molecule TSP-1 plays a role in normal central nervous system development by contributing to the regulation of oligodendrocyte precursor migration. PMID- 9373032 TI - In situ expression of fibroblast growth factor receptors by oligodendrocyte progenitors and oligodendrocytes in adult mouse central nervous system. AB - Basic fibroblast growth factor (bFGF) induces proliferation and alters differentiation of cultured oligodendrocyte lineage cells. In situ, bFGF is present in normal adult central nervous system (CNS) and upregulated during an early stage of various pathological conditions. We examined the expression of receptors for bFGF (FGFRs) by oligodendrocyte progenitors and oligodendrocytes in situ in normal adult mouse CNS to further understand the potential in situ response to bFGF. We found FGFR immunoreactivity in oligodendrocyte progenitors, identified by expression of NG2 or platelet-derived growth factor alpha receptor (PDGFalphaR), and in oligodendrocytes expressing 2',3'-cyclic nucleotide 3' phosphodiesterase. Particularly interesting is the demonstration that oligodendrocyte progenitors simultaneously expressing receptors for both bFGF and PDGF-AA are present in normal adult CNS. Since in vitro bFGF and PDGF-AA in combination induce oligodendrocyte progenitors from normal adult CNS to undergo rapid proliferation and migration, the in situ coexpression of FGFRs and PDGFalphaR supports the hypothesis that oligodendrocyte progenitors can respond to bFGF and PDGF-AA in situ, and that both growth factors may be critical for repopulation of demyelinated lesions during remyelination. PMID- 9373031 TI - FGF-2 converts mature oligodendrocytes to a novel phenotype. AB - Fibroblast growth factor (FGF)-2 differentially regulates oligodendrocyte progenitor proliferation and differentiation in culture, and modulates gene expression of its own receptors, in a developmental and receptor type-specific manner (Bansal et al., 1996a,b). Three FGF receptors (types 1, 2, 3) are expressed in postmitotic, terminally differentiating oligodendrocytes. Exposure of such cells to FGF-2 results in: (a) the down-regulation of myelin-specific gene expression (e.g., ceramide galactosyltransferase, 2',3'-cyclic nucleotide 3' phosphohydrolase, myelin basic protein, proteolipid protein), (b) dramatic increases in the length of cellular processes in a time- and dose-dependent manner, (c) re-entrance into the cell cycle without accompanying mitosis, and (d) the alteration of the expression of both low- and high-affinity FGF receptors. Compared to oligodendrocyte progenitors, the differentiated oligodendrocytes treated with FGF-2 incorporate BrdU at a slower rates, exhibit different patterns of both FGF high- and low-affinity (syndecans) receptors, and are morphologically very different. In addition, they do not re-express the progenitor markers A2B5, NG2 or PDGFalpha receptor. Therefore, although the FGF-treated cells lose their differentiated OL/myelin markers, they do not revert to progenitors and clearly represent a different, apparently novel, phenotype both morphologically and biochemically, which we have termed NOLs. These data indicate that terminally differentiated oligodendrocytes retain the plasticity to reprogram their differentiation fate under the influence of environmental factors. The possible significance of this response to FGF relative to normal and pathological physiology is discussed. In particular, on the basis of these data we predict the appearance of cells in and around multiple sclerosis plaques with the phenotype O4+, NG2-, A2B5-, O1-, MBP-. PMID- 9373033 TI - CNP overexpression induces aberrant oligodendrocyte membranes and inhibits MBP accumulation and myelin compaction. AB - 2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP) is highly enriched in myelin forming cells where it is concentrated at the cytoplasmic side of all surface membranes except those of compact myelin. Previous studies have provided evidence that CNP is functionally involved in migration or expansion of membranes during myelination. This hypothesis is supported, in part, by the production of aberrant myelin membranes in transgenic mice that have a 6-fold increase in CNP expression. In addition, many myelin lamellae in these CNP-overexpressing mice lacked major dense lines (MDLs). The purpose of the present study was to determine if CNP overexpression altered: (1) oligodendrocyte and myelin membrane production during early stages of myelination, and (2) the ultrastructural distribution of CNP and myelin basic protein (MBP) in myelin membranes. We identified aberrant membrane expanses that extended from premyelinating oligodendrocyte processes, the periaxonal membrane, and the contact point between oligodendrocyte processes and myelin internodes. Myelin membranes without MDLs were deficient in MBP and enriched in CNP. These data support a functional role for CNP during oligodendrocyte membrane expansion and indicate, for the first time, that CNP may help target MBP to compact myelin. PMID- 9373034 TI - CNP2 mRNA directs synthesis of both CNP1 and CNP2 polypeptides. AB - The ribosome scanning model for translational initiation predicts that eukaryotic mRNAs should, as a rule, be monocistronic. However, cases have recently been described of eukaryotic mRNAs producing more than one protein through alternative translational initiation at several different AUG codons. The present work reports the occurrence of two translational start sites on the mRNA encoding isoform 2 of the myelin marker enzyme 2',3'-cyclic nucleotide 3' phosphodiesterase (CNP) in rat and mouse. We show that the CNP2 mRNA is able to direct synthesis of not only CNP2, but also CNP1 polypeptide. Immunoprecipitation experiments using a polyclonal antibody directed against CNP detect both CNP isoforms in tissues or cell lines expressing only the CNP2 transcript. Thus, the synthesis of CNP1 and CNP2 polypeptides must be encoded by the CNP2 transcript. In vitro translation of synthetic CNP2 mRNA demonstrates that both CNP isoforms are synthesized by initiation at different AUG codons. Furthermore, by introducing mutations to "switch off" translation from the second in-frame AUG codon in the CNP2 cDNA, and transfecting 293T cells with those constructs, we are able to correlate the production of CNP1 and CNP2 with different translational start sites. These results lead us to conclude that the CNP2 mRNA is able to produce both CNP1 and CNP2 polypeptides. This investigation has altered our understanding of the temporal expression of the CNP protein isoforms during development of the central nervous system (CNS). PMID- 9373035 TI - Nuclear transport of myelin basic protein. AB - The multiple myelin basic protein (MBP) isoforms expressed by myelinating cells are now known to have different expression patterns. The relative abundance of the isoforms containing exon II is greater early in myelinogenesis, whereas in compact myelin the isoforms lacking this exon are more abundant. Further, the individual MBPs exhibit different intracellular localizations, indicating that the isoforms may not be functionally equivalent in myelinating cells. The major MBPs (14 kD and 18.5 kD) have strong affinity for membranes, while on the other hand, the less abundant isoforms (17 kD and 21.5 kD) localize to the nucleus of young oligodendrocytes, suggesting a regulatory role in the myelination program. The same intracellular distribution patterns have been observed when the MBPs are expressed in Hela cells and in shiverer oligodendrocytes. Thus, the intracellular fate of these proteins seems to be generally directed through alternative expression of exon II. Furthermore, the extent of MBPexII entry into the nucleus was found to be directly related to the growth state of host cells. In this paper, we demonstrate that nuclear proteins constitutively expressed by Hela cells also exhibit an apparently growth-related nucleo-cytoplasmic distribution revealing that MBPexII exhibits the same behavior as bona fide nuclear proteins. Also, to further characterize MBP nuclear transport, we explored various parameters of the translocation of MBP into the nucleus using an in vitro system. This experimental paradigm permits the uncoupling of synthesis and translocation events; thus, the transport of MBP into cell nuclei can be studied as a function of time. We also evaluated how changes in temperature as well as energy depletion affect the in vitro nuclear transport of MBP. PMID- 9373036 TI - Golli-MBP proteins mark the earliest stages of fiber extension and terminal arboration in the mouse peripheral nervous system. AB - The Golli-myelin basic protein (MBP) transcription unit gives rise to two sets of products. One set (i.e., the MBPs) is expressed exclusively in myelin forming cells and the other set (i.e., the golli isoforms) is expressed in both oligodendrocytes and neurons in the CNS. The two major golli proteins, generated from RNAs transcribed from the most upstream promoter of the gene, contain MBP peptide sequences in their C-terminal halves and are, therefore, structurally and immunologically related to the MBPs. We have examined the distribution and localization of golli proteins in the mouse peripheral nervous system (PNS) using immunocytochemistry with a golli-specific antibody. Golli immunoreactivity was first observed in sensory and motor fibers of the mouse at E11 during fiber tract extension, but prior to the maturation of terminal connections. Once neuromuscular junctions had formed, golli immunoreactivity appeared in motor endplates and persisted to the latest age examined, P60. Golli immunoreactivity was also observed in the cell bodies and processes of the dorsal root ganglia throughout development. Strong staining in the PNS of the dysmyelinating mutant shiverer suggested that the major golli protein in peripheral fibers was the BG21 isoform. Interestingly, golli immunoreactivity was also found in adrenal chromaffin cells, which share a common neural crest derivation with other postganglionic neurons that express golli protein. These results suggest that in addition to its role in early forming neuronal systems of the CNS, golli protein also plays a role in the early development and maintenance of neurons in the PNS. PMID- 9373037 TI - Myelin transcription factor 1 (Myt1) of the oligodendrocyte lineage, along with a closely related CCHC zinc finger, is expressed in developing neurons in the mammalian central nervous system. AB - The establishment and operation of the nervous system requires genetic regulation by a network of DNA-binding proteins, among which is the zinc finger superfamily of transcription factors. We have cloned and characterized a member of the unusual Cys-Cys-His-Cys (also referred to as Cys2HisCys, CCHC, or C2HC) class of zinc finger proteins in the developing nervous system. The novel gene, Myt1-like (Myt1l), is highly homologous to the original representative of this class, Myelin transcription factor 1 (Myt1) (Kim and Hudson, 1992). The MYT1 gene maps to human chromosome 20, while MYT1L maps to a region of human chromosome 2. Both zinc finger proteins are found in neurons at early stages of differentiation, with germinal zone cells displaying intense staining for MyT1. Unlike Myt1, Myt1l has not been detected in the glial lineage. Neurons that express Myt1l also express TuJ1, which marks neurons around the period of terminal mitosis. The Myt1l protein resides in distinct domains within the neuronal nucleus, analogous to the discrete pattern previously noted for Myt1 (Armstrong et al.: 14:303-321, 1995). The developmental expression and localization of these two multifingered CCHC proteins suggests that each may play a role in the development of neurons and oligodendroglia in the mammalian central nervous system. PMID- 9373038 TI - Transient expression of the neurofilament proteins NF-L and NF-M by Schwann cells is regulated by axonal contact. AB - Expression of the genes that encode neurofilament proteins is considered to be confined normally to neurons. However, in demyelinating peripheral nerves Schwann cells upregulate the mRNA for the medium-sized neurofilament protein (NF-M), and cultured Schwann cells of the myelin-forming phenotype can also synthesize and incorporate NF-M protein into their intermediate filament (IF) cytoskeleton. The purpose of this study was to establish how axonal contact might influence glial neurofilament gene expression and regulate the synthesis of neurofilament proteins. We show that the gene encoding NF-M is expressed at early stages of differentiation in myelin-forming Schwann cells in vivo; nevertheless, little NF M protein can be detected in these cells. The transient induction of NF-M mRNA is also apparent in dedifferentiating Schwann cells during Wallerian degeneration. In these Schwann cells the mRNAs for NF-M and NF-L (the smallest polypeptide), but not NF-H (the largest neurofilament subunit), are coordinately expressed. In contrast to differentiating myelin-forming Schwann cells, the cells of degenerating nerves express both NF-M and NF-L polypeptides. Restoration of axonal contact in the growing nerve stimulates the recapitulation of Schwann cell differentiation including the elevation of NF-M and NF-L mRNA expression. These results demonstrate that the transient induction of neurofilament mRNAs in Schwann cells is a feature of both differentiation and dedifferentiation. However translation of these mRNAs is confined to Schwann cells deprived of axonal contact either by nerve injury or by culture in the absence of axons. These findings suggest that the expression of the NF-M and NF-L polypeptides is an important characteristic of those Schwann cells that will contribute to the repair of damaged peripheral nerves. PMID- 9373039 TI - Glial- and fat-specific expression of the rat glycerol phosphate dehydrogenase luciferase fusion gene in transgenic mice. AB - Glycerol phosphate dehydrogenase (GPDH) is a metabolic enzyme that catalyzes the conversion of dihydroxyacetone phosphate to glycerol-3-phosphate. It provides phospholipid precursors for lipid biosynthesis and energy metabolism. In the brain, GPDH enzymatic activity, protein, mRNA are exclusively associated with oligodendroglial and Bergmann glial cells. Expression of GPDH in the brain increases dramatically during the active period of myelination, and is regulated by extracellular signals. In an effort to understand the mechanism that confers glial-specific expression of GPDH, we have examined the role of the 5' flanking sequence of the rat GPDH gene in conferring cell-specific expression of reporter gene in transgenic mice. Luciferase reporter constructs containing either the full-length GPDH 5' flanking region (p4.3), or a distally truncated version (p2.6), were injected into mouse zygotes. Three independent lines of transgenic mice containing the p4.3, and seven lines of mice containing the p2.6 constructs, were analyzed. Luciferase enzyme activity was detectable only in brain and fat, not in other GPDH-positive organs such as liver, muscle, and kidney. Both the full-length and the distally deleted transgenes were expressed similarly in these two organs, indicating that the distal portion of the 5' flanking region was not required for brain- and fat-specific expression. Immunocytochemical analyses revealed that luciferase immunoreactivity colocalized with glial fibrillary acidic protein (GFAP)-positive Bergmann glia in the cerebellum, and myelin basic protein (MBP)-positive oligodendroglia in the cerebral cortex and the brainstem. Results here suggest that the rat GPDH 5' flanking region directs glial-specific expression of GPDH transcription in the brain, and provide a good model for analyses of changes in glial metabolism in response to extracellular perturbations in vivo. PMID- 9373040 TI - Immune system-related CD9 is expressed in mouse central nervous system myelin at a very late stage of myelination. AB - CD9 is a tetra-membrane-spanning glycoprotein involved in cell adhesion, migration, and proliferation in both the immune and the immature nervous system. In this study, CD9 expression was detected in myelin of mouse brain, starting at postnatal day 16. The amount of CD9 protein continuously increased with age and persisted in the adult brain. It appeared later than myelin proteolipid protein (PLP), a typical late myelin marker. Mature oligodendrocytes were abundant in CD9, although it was also detected in astrocytes and microglial cells in vitro. CD9 appeared at the end of the myelination process and was localized along the outermost membrane of compact myelin. CD9 is known to associate with integrins, which are candidate receptors for extracellular matrix and transmit extracellular signals into the cells. Taken together, CD9 at the surface of central nervous system (CNS) mature myelin may have a unique function to facilitate signal transduction and enhance myelin membrane adhesion to extracellular matrices at very late stages of development. PMID- 9373041 TI - Sodium channel distribution in axons of hypomyelinated and MAG null mutant mice. AB - Na+ channel organization was studied with immunofluorescence in the peripheral nervous system of mice genetically altered to produce abnormal myelin. In two of these strains, transcription of inserted transgenes was targeted to myelinating Schwann cells through linkage to a promoter for the myelin protein P0. Adults of both of these strains had hindlimb paralysis and a tremor on lifting by the tail. In one case, Schwann cells were eliminated via expression of the diphtheria toxin A chain (DT-A). During postnatal days 3-7, Na+ channel clustering at forming nodes was dramatically reduced compared with that of normal animals. At 1-3 months of age, Na+ channel immunofluorescence was often found spread over long stretches of the axolemma, instead of being confined to nodal gaps. In the second P0-linked transgenic model, Schwann cell expression of the large T antigen tsA 1609 resulted in cell cycle dysfunction. Adult axons had regions of diffuse Na+ channel labeling. Focal clusters were rare within these zones, which were characterized by a series of cells of myelinating phenotype tightly apposed to the axon. Previous studies suggested that Schwann cells had to reach the stage of ensheathment characterized by periaxonal myelin associated glycoprotein (MAG) expression in order to induce Na+ channel clustering. However, in MAG-deficient mice, Na+ channel labeling patterns within sciatic nerves were normal. PMID- 9373042 TI - Local recruitment of remyelinating cells in the repair of demyelination in the central nervous system. AB - The distance over which remyelinating cells within surrounding intact tissue are stimulated to respond to a demyelinating lesion and migrate toward it is unknown. To address this issue we have conducted a series of experiments in which the generation of remyelinating cells in tissue surrounding a spontaneously repairing area of demyelination induced in the adult rat spinal cord is suppressed by exposure to X-irradiation. By regulating the area of X-irradiation relative to the length of the demyelinating lesion within dorsal white matter we have shown that remyelinating cells are not recruited over distances greater than 2 mm into areas of demyelination, implying that most of the remyelinating cells are locally generated. This result indicates that there is only a narrow rim of normal tissue surrounding an area of demyelination from which remyelinating cells can be recruited. The depletion of cells within this rim may account for the poor remyelination associated with large areas of demyelination and following repeated episodes of demyelination. We have also shown that, in contrast to Schwann cells, oligodendrocyte lineage cells recruited into lesions have a limited ability to rapidly repopulate large areas of demyelination. Attempts to enhance remyelination in situations where it fails should therefore focus on increasing the size of the surrounding area from which remyelinating cells can be recruited by augmenting the level of recruitment signal, and preventing premature differentiation of oligodendrocytes so as to maximize their migratory and proliferative potential. PMID- 9373043 TI - PK11195 binding to the peripheral benzodiazepine receptor as a marker of microglia activation in multiple sclerosis and experimental autoimmune encephalomyelitis. AB - Activated glial cells are implicated in regulating and effecting the immune response that occurs within the CNS as part of multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). The peripheral benzodiazepine receptor (PBR) is expressed in glial cells. We examined the utility of using in vitro and in vivo ligand binding to the PBR as a measure of lesion activity in autoimmune CNS demyelinating diseases. Applying a combined autoradiography and immunohistochemical approach to spinal cord and brain tissues from mice with EAE, we found a correlation at sites of inflammatory lesions between [3H]-PK11195 binding and immunoreactivity for the activated microglial/macrophage marker Mac-1/CD11b. In MS tissues, [3H]-PK11195 binding correlated with sites of immunoreactivity for the microglial/macrophage marker CD68, at the edges of chronic active plaques. Positron emission tomography (PET) imaging with [11C]-PK11195 showed ligand uptake only at sites of active MS lesions defined by magnetic resonance imaging criteria. Our results indicate the potential to develop markers suitable for both in vitro and in vivo use, which will serve to help correlate phenotypic and functional properties of cells which participate in disease or injury responses within the CNS. PMID- 9373044 TI - Symptomatic improvement after AV nodal ablation and pacemaker implantation for refractory atrial fibrillation and atrial flutter. AB - Symptomatic Improvement was evaluated in 64 patients with drug-refractory atrial fibrillation or atrial flutter who underwent atrioventricular (AV) nodal ablation and permanent pacemaker implantation. The arrhythmias were chronic in 40 patients and paroxysmal in 24 patients. All were refractory to multiple drugs (3.7 +/- 1.5) and had severe symptoms: palpitations (58 patients), dyspnea (n=58), dizziness (n=38), asthenia (n=37), and chest pain (n=20). All underwent AV nodal ablation and single- (n=39) or dual-chamber (n=25) pacemaker implantation. During follow-up of 20.4 +/- 17.8 months, palpitations improved in 100% of 58 patients who had palpitations before the ablation, dyspnea improved in 75% of 58 patients, chest pain in 95% of 20 patients, asthenia in 75% of 37 patients, and dizziness in 93% of 38 patients. Moderate to significant improvement in these symptoms was reported in 83% of patients and mild improvement in 5%. Before ablation, 77% of patients were in New York Heart Association functional class III or IV. After ablation, 19% of patients were in the same functional classes (P < 0.05). Thus, AV nodal ablation and pacemaker implantation in patients with drug-refractory atrial fibrillation or flutter was associated with significant improvement in presenting symptoms and functional capacity. A randomized, controlled study is needed to compare this form of therapy with other therapeutic modalities. PMID- 9373045 TI - Pitfalls in the echocardiographic diagnosis of aortic dissection. AB - The authors studied 25 patients with transthoracic echocardiography (TTE) and/or transesophageal echocardiography (TEE) for suspected aortic dissection. Of these, aortic dissection was diagnosed correctly in 19 patients, but in 6 the echocardiographic findings for dissection were atypical or false-positive. In patient 1, the TEE revealed a dilatated proximal aortic root. TEE showed a possible flap but was nondiagnostic. The diagnosis was made by computed tomography (CT) and confirmed at surgery to be type 1 dissection. In patient 2, the TTE depicted flail aortic cusps, questionable vegetations, and dilatated aortic root. In patient 3, TTE demonstrated moderate pericardial effusion with hematoma but no dissection. Type 1 dissection was subsequently confirmed at autopsy in both. Patient 4 had TEE diagnosis of type 3 dissection. However, reevaluation of the study by a senior sonographer just prior to surgery led to the correct diagnosis of type 1 dissection. Patients 5 and 6 had dilatated ascending aortas with linear echoes within the lumen on TEE and were reported as having type 1 dissections. CT and/or angiography did not reveal dissection in either patient. In conclusion, TTE and TEE are vaulable tests in diagnosing aortic dissection. However, atypical features, misdiagnosis of the site of dissection, or false-positive studies can occur. PMID- 9373046 TI - The effect of cigarette smoking on free-living daily physical activity in older claudication patients. AB - The purposes of this study were (1) to determine whether peripheral arterial occlusive disease (PAOD) patients who smoke have a lower free-living daily physical activity than nonsmoking patients and (2) to determine whether the difference in physical activity persisted after controlling for potential confounders such as PAOD severity, age, body composition, and peripheral circulation. Thirty-four smokers (45.5 +/-9.8 years of smoking) and 43 nonsmokers (former smokers who had a smoking history of 35.0 +/- 13.1 years who quit 12.2 +/ 10.5 years prior to investigation) were studied. Patients wore a Caltrac accelerometer and a pedometer on each hip over two consecutive weekdays to assess free-living daily physical activity. Patients were also characterized on age, weight, body mass index (BMI), percent body fat, ankle/brachial index (ABI), calf blood flow, and exercise capacity. The smoking and nonsmoking claudication patients had a similar level of PAOD severity, for no group differences were noted in ABI (P=0.287) and treadmill time to maximal claudication pain (P=0.201). However, the smokers were 35% less physically active than the nonsmokers (264 +/- 123 vs 407 +/- 272 kcal/day; P<0.006), and they took 23% fewer steps (4,116 +/- 2,199 vs 5,329 +/- 2,924 steps/day; P<0.034). After adjustment for group differences in age, weight, BMI, percent body fat, and calf blood flow, the lower activity level of the smokers persisted. The adjusted daily energy expenditure was 27% lower (292 +/- 105 vs 400 +/- 214 kcal/day; P=0.021), and the adjusted amount of daily walking was 29% lower (4,039 +/- 1,760 vs 5,684 +/- 2,235 steps/day; P=0.003). Smoking PAOD patients had a less physically active lifestyle than nonsmoking patients, and the lower activity level of the smokers was independent of PAOD severity, age, body composition, and peripheral circulation. PMID- 9373047 TI - Effects of serial percutaneous application of carbon dioxide in intermittent claudication: results of a controlled trial. AB - In a prospective, controlled clinical trial, serial application of carbon-dioxide enriched water was compared with fresh water. Twenty-four patients with peripheral arterial occlusive disease (stable claudication) were randomly allocated to one of two serial intervention groups, lower extremities immersed in either fresh water or in CO2-enriched water (1000 mg CO2/kg) water under standardized conditions (temperature, 33 degrees C; depth, 40 cm; immersion time, 30 min; five times a week over 4 weeks). The serial application of carbon-dioxide enriched water increased arterial peak flow (reactive hyperemia), transcutaneous oxygen tension (basal value and half-recovery-time), and pain-free walking distance. The serial fresh water application did not change these values. The authors conclude that serial carbon dioxide application can be clinically effective in patients with arterial obstructions in the lower extremities. PMID- 9373048 TI - ET-1 plasma levels during cold stress test in sclerodermic patients. AB - Endothelial cell injury in blood vessels of small arteries and capillaries is considered the primary event in the pathogenesis of systemic sclerosis (SSc). Because endothelin-1 (ET-1) is mainly released in the site of endothelial cell damage, thereby inducing a potent vasoconstriction, it was our intention to study ET-1 release in a group of SSc patients during a cold pressor test (CPT). Twelve SSc patients and a control group of 10 healthy subjects underwent CPT. Blood samples for ET-1 assay were collected at 90 and 180 seconds of exposure to cold stress. Heart rate and blood pressure were recorded at the same intervals. A capillaroscopic examination was performed in both groups before and after CPT. We observed significantly higher levels of plasma ET-1 in SSc patients compared with those of the control group at baseline (P=0.007) and at 90 (P=0.006) and 180 seconds (P=0.03) of CPT. During the test, the capillaroscopic examination showed a dramatic worsening of the vascular picture that was parallel to the increase in ET-1 plasma levels. This suggests that higher ET-1 plasma levels can have a part in the acute vascular reactivity of SSc patients undergoing CPT. PMID- 9373049 TI - The coronary angiogenetic effect of heparin: experimental basis and clinical evidence. AB - Heparin is a highly sulfated polysaccharide consisting of a repeating disaccharide structure as found in other glycosaminoglycanes. The intravenous and subcutaneous formulation of the drug is routinely used for its well-known, time honored antithrombotic effect. However, available evidences linking heparin to angiogenesis raise the possibility of a therapeutically relevant antiischemic effect of the drug. Molecular biology data show that in a hypoxic milieu heparin could facilitate angiogenesis through interactions with a family of polypeptide growth factor mitogens that stimulate endothelial cell proliferation. Experimental data suggest that heparin can augment collateral circulation when combined with other potentially angiogenetic factors, such as repeated ischemia, coronary occlusion, or physical exercise. Clinical data, although very initial, encompassing a total of only 41 heparin-treated patients with coronary artery disease, suggest that heparin facilitates collateral development stimulated by exercise-induced myocardial ischemia in humans. According to the heparin collateral hypothesis, the mechanism of action of heparin as an antiischemic medication would be independent of its anticoagulant action. The molecular targets of heparin are Factor Xa and IIa for antithrombotic action, heparin binding growth factors (including fibroblast growth factor and vascular endothelial growth factor) for angiogenesis. The antithrombotic effect is not linked to a cellular target, whereas the angiogenetic effect directly stimulates endothelial cells. The molecular cofactor required for effect is antithrombin III for antithrombosis, and possibly endogenous adenosine for angiogenesis. The therapeutic effect is achieved within minutes or hours for antithrombosis, and within weeks or months for angiogenesis. PMID- 9373050 TI - Antihypertensive and renal effects of isradipine in essential hypertension: focus on renin system activity. AB - Calcium antagonists are known to exert various effects on the kidney that might modulate their antihypertensive potential. This study evaluated the renal effects, along with the efficacy, of isradipine in two subgroups of patients with mild to moderate essential hypertension (EH), defined according to plasma renin activity (PRA). Twenty-six patients were randomly assigned to receive 12-week treatment with slow-release isradipine (2.5-5 mg) or placebo. Assessment of PRA related to concurrent 24-hour sodium excretion was used to define patients with high/medium (n=16) and low renin profile (n=10). Urinary albumin excretion (UAE), serum creatinine and glomerular filtration rate (GFR, as endogenous creatinine clearance) were measured. Blood pressure (BP) decrease with isradipine was greater in the low PRA group as compared with the high/medium PRA group (P<0.05), and normalization of BP was achieved in all low-renin patients compared with 57% in the high/medium PRA group. BP reduction in the placebo group was statistically not significant. Isradipine, but not placebo, induced significant reduction in UAE (P<0.05); the decrease was similar in both PRA groups. Treatment did not cause any significant changes in GFR, PRA, urinary sodium or creatinine excretion, or serum aldosterone or creatinine concentrations. The decrease of BP in the whole isradipine-treated group was inversely correlated with pretreatment serum creatinine as well as with basal urinary creatinine excretion. In conclusion, the antihypertensive effect of isradipine was more pronounced in low renin EH patients, despite similar effects on renal function and UAE in both PRA groups. PMID- 9373051 TI - Aortic dissection decades following internal carotid artery dissection--report of two cases. AB - Recurrent dissections involving carotid, vertebral, or renal arteries have been described in patients with spontaneous cervical artery dissections, with a maximal interval between dissections of fourteen years. The authors describe 2 patients in whom aortic dissections developed twenty-five and forty years, respectively, following carotid artery dissections. These 2 patients constituted 8% of the total number of patients from Rochester, Minnesota, who were diagnosed with aortic dissection between 1987 and 1992. The first patient, a forty-five year-old woman, presented in 1948 with right neck pain and headache, associated with several episodes of transient numbness of the right face and numbness and clumsiness of the left upper and lower extremities. Examination showed right miosis. Angiography showed a stenosis of the extracranial right internal carotid artery beginning several centimeters from the bifurcation. She died at age eighty five from an aortic dissection. The second patient, a thirty-eight-year-old man, noted left orbital and frontotemporal headaches and drooping of the left eyelid in 1962. Examination showed left oculosympathetic palsy. Angiography showed stenosis and an aneurysm in the midportion of the extracranial left internal carotid artery. He died at age sixty-three from an aortic dissection. These cases suggest that following a carotid artery dissection the risk of a recurrent arterial dissection may remain elevated for a prolonged period of time and the recurrent dissection may involve the aorta. PMID- 9373052 TI - Symptomatic reinfarctation of a previously silent myocardial region four months after successful reperfusion--a case report. AB - Coronary collateral circulation helps to preserve myocardial perfusion distal to severely stenotic or totally obstructed coronary arteries. The presence or absence of angina pectoris and the state of myocardial function depend on the extent of collateralization and its functional contribution to myocardial blood flow. Clinical and experimental observations have suggested that newly developed collaterals usually remain even after successful revascularizaton. The authors present a case of a patient with extensive intercoronary collaterals and hibernating myocardium after an acute inferior wall myocardial infarction who underwent successful percutaneous transluminal coronary angioplasty of a totally obstructed, dominant right coronary artery and then experienced extensive reinfarction following reocclusion 4 months later. This case demonstrates failure of extensive collaterals to prevent acute myocardial infarction. PMID- 9373053 TI - Acetylcholine-induced coronary microvascular vasospasm in a patient with angina pectoris and normal coronary angiogram--a case report. AB - We demonstrated a continuous intracoronary infusion of acetylcholine-induced marked decrease of coronary blood flow estimated by intracoronary Doppler flow wire without significant epicardial coronary narrowing. This case can be called a patient with microvascular vasospastic angina. PMID- 9373054 TI - Simultaneous presence of a large coronary aneurysm and ectasia in a young patient with myocardial infarction--a case report. AB - Idiopathic or congenital coronary artery ectasias and aneurysms are uncommon forms of coronary artery disease. The prognosis and optimal management of such patients remains unknown. The authors describe the case of an otherwise healthy 30-year-old man with concomitant severe right coronary artery ectasia and left main coronary artery aneurysm who sustained a mild anterior myocardial infarction. There was no obstructive coronary artery disease, and no cause for the lesions could be identified. Chronic anticoagulation and antiplatelet therapy were initiated with resolution of symptoms. PMID- 9373056 TI - Eosinophilic myocarditis complicated by acute myocardial infarction--a case report. AB - The authors report a patient with eosinophilic myocarditis who developed severe chest pain with marked elevation of the ST segment on the electrocardiogram, which led them to suspect the presence of acute myocardial infarction. Emergency coronary angiography showed numerous occlusions and stenoses at the distal right and left coronary arteries, especially affecting the latter, owing probably to thrombus. The angiographic findings in this case demonstrate the formation and obstruction of thrombus in the small coronary arteries in a patient in the acute necrotic stage of eosinophilic myocarditis, believed to be the first such case reported. PMID- 9373055 TI - Transesophageal echocardiographic Doppler study of coronary flow in a patient with myocardial bridging--a case report. AB - A case report of myocardial bridging of the left anterior descending artery is described. Coronary flow proximal to the myocardial bridge was studied with transesophageal echo Doppler. The patient, a 62-year-old farmer who sustained an anterior myocardial infarction, underwent thrombolysis and was admitted. He subsequently underwent coronary angiography and left ventriculography, which showed a severe myocardial bridge of the midshaft of the left anterior descending artery. The ejection fraction improved from 25 to 48% after thrombolysis, as measured by using echocardiography. Transesophageal Doppler study proximal to the myocardial bridge revealed a relative increase of the diastolic coronary flow velocity (increased acceleration), which reached its peak value in early diastole. Despite the presence of severe myocardial bridging, coronary flow reserve increased substantially two minutes after the infusion of dipyridamole (0.56 mg/kg iv for 4 minutes). Transesophageal Doppler study of coronary blood flow proximal to the myocardial bridge in the left anterior descending artery showed a characteristic waveform that may prove to be indicative of this condition. PMID- 9373057 TI - Sustained dapsone-induced remission of hypocomplementemic urticarial vasculitis- a case report. AB - Hypocomplementemic urticarial vasculitis (HUV) is often misdiagnosed. The response to drug therapy may be unsatisfactory, and immunosuppressive therapy may be associated with significant side effects. A 35-year-old patient whose condition was resistant to cyclophosphamide, corticosteroids, pentoxyphylline, cyproheptadine, sulindac, and colchicine was maintained in remission with dapsone, which may be the drug of choice for HUV. Emphysema has been reported to complicate HUV, but this is the first account of vasculitis-related emphysema with no confounding history of tobacco smoke exposure. The relationship of proteolytic injury to the pulmonary and other manifestations is considered, as is the possible role for dapsone in reducing it. PMID- 9373058 TI - 1997 Founders Award--Genevieve S. Roessler. 42nd Annual Meeting of the Health Physics Society, San Antonio, TX 29 June-3 July 1997. PMID- 9373059 TI - 1997 Founders Award--John P. "Jack" Corley. 42nd Annual Meeting of the Health Physics Society, San Antonio, TX 29 June-3 July 1997. PMID- 9373060 TI - 1997 Elda E. Anderson Award--Jack F. Higginbotham. 42nd Annual Meeting of the Health Physics Society, San Antonio, TX 29 June-3 July 1997. PMID- 9373061 TI - 1997 Distinguished Scientific Achievement Award--John R. Johnson. 42nd Annual Meeting of the Health Physics Society, San Antonio, TX 29 June-3 July 1997. PMID- 9373062 TI - 1997 William McAdams Outstanding Service Award--Robert Martin Ryan. American Board of Health Physics. 42nd Annual Meeting of the Health Physics Society, San Antonio, TX 29 June-3 July 1997. PMID- 9373063 TI - 1997 National Registry of Radiation Protection Technologists Arthur F. Humm, Jr., Memorial Award--Ronald C. Schrotke. 42nd Annual Meeting of the Health Physics Society, San Antonio, TX 29 June-3 July 1997. PMID- 9373064 TI - 1997 Evans Medal--Constantine J. Maletskos. 42nd Annual Meeting of the Health Physics Society, Seattle, WA 29 June-3 July 1997. PMID- 9373065 TI - Down syndrome and ionizing radiation. AB - This review examines the epidemiologic and experimental studies into the possible role ionizing radiation might play in Down Syndrome (trisomy 21). It is prompted by a report of a temporal cluster of cases of this chromosomal disorder observed in West Berlin exactly 9 mo after the radioactive cloud from Chernobyl passed. In approximately 90% of cases, Down Syndrome is due to the nondisjunction of chromosome 21, most often in the oocyte, which may be exposed to ionizing radiation during two separate periods: before the completion of the first meiosis or around the time of ovulation. Most epidemiologic studies into trisomies and exposure to ionizing radiation examine only the first period; the Chernobyl cluster is related to the second. Analysis of these epidemiologic results indicates that the possibility that ionizing radiation might be a risk factor in Down Syndrome cannot be excluded. The experimental results, although sometimes contradictory, demonstrate that irradiation may induce nondisjunction in oogenesis and spermatogenesis; they cannot, however, be easily extrapolated to humans. The weaknesses of epidemiologic studies into the risk factors for Down Syndrome at birth (especially the failure to take into account the trisomy cases leading to spontaneous abortion) are discussed. We envisage the utility and feasibility of new studies, in particular among women exposed to prolonged or repeated artificially-produced ionizing radiation. PMID- 9373066 TI - Assessment of dose equivalent due to neutrinos. AB - Neutrinos are present in the natural environment and are also produced by particle accelerators. A recent hypothesis has also been proposed that asserts that ionizing radiation due to neutrinos from certain astronomical events may have led to the extinction of some biological species. Thus, it is of interest to be able to estimate the dose equivalent due to these weakly interacting particles. Presented here are methods for estimating the dose equivalent due to neutrinos over a broad domain of energy, examples of such calculations, and an assessment of the postulated role of neutrinos in biological extinctions. It is concluded that the dose equivalent due to neutrinos from natural sources and from present-day accelerators is inconsequential and the postulated role of neutrinos in biological extinctions is highly improbable. PMID- 9373067 TI - Multifactorial analysis of lung cancer dose-response relationships for workers at the Mayak nuclear enterprise. AB - Dose-response relationships for alpha-radiation-induced lung cancers (adenocarcinoma, squamous carcinoma and small cell carcinoma) were developed by multifactorial analysis using data for Mayak nuclear enterprise workers chronically exposed by inhalation to 239Pu. The three most important lung cancer risk factors (smoking, plutonium incorporation, and external gamma irradiation), out of six factors previously identified, were used. Relative risks (odds ratios) were determined for 500 nuclear enterprise workers (162 cancer cases, 338 control) for different dose levels using a case-control study design and logistic regression. A threshold at about 3.7 kBq or 0.80 Gy was discovered for incorporated plutonium, which is satisfactorily described by linear-quadratic and quadratic models. Excess relative risk was 0.020 kBq(-2) and 0.97 Gy(-2). This quadratic function was mainly due to adenocarcinoma. A trend for decreasing risk was noted for the lowest levels of plutonium incorporation, near permissible level. No clear-cut dose-response relationship for lung cancer induction by chronic external gamma irradiation was obtained. Lung cancer induction by cigarette smoking had a linear dependence: smoking of one pack of papiroses (a type of Russian cigarette) per day for 5 y increases the lung cancer risk twofold. The effect was most clearly manifested for squamous-cell carcinoma. PMID- 9373068 TI - Variation of 222Rn in public drinking water supplies. AB - The U.S. Environmental Protection Agency has proposed regulating 222Rn in public drinking water. When implemented, the regulation will require periodic sampling to demonstrate compliance. The work reported in this paper was conducted to evaluate how reliably grab samples can be used to characterize the average 222Rn concentration in a groundwater source. Periodic samples were collected from 14 wells over sampling periods ranging from 2 to 26 mo. Samples were collected using a "slow-flow" collection method, and samples were analyzed using liquid scintillation techniques. The results reveal variation in 222Rn concentration over the study period; however, for the 1,468 samples collected from the 14 wells, approximately 97% of the measurement results were within 30% of the mean value for the well. PMID- 9373069 TI - Leaching of accelerator-produced radionuclides. AB - Leaching of radionuclides produced in soil and rock by high energy proton-induced radiation was studied for the SSC site. Comparison was made with predictions of a Monte Carlo code CASIM and previous results for the Fermilab site. The principal long-lived radionuclides were 3H and 22Na in agreement with Fermilab results. A few other radionuclides were present at lower concentrations in a subset of the samples. For example, 134Cs was detected in a few SSC water samples. Leaching from SSC chalk was dependent on previous weathering and on leaching time. The more soil-like marl and shale were leached more rapidly. Results of this study, in conjunction with the SSC groundwater model, show that adequate groundwater protection would have been maintained for an accidental loss of the entire proton beam at a point in the SSC Collider tunnel. Early warning techniques developed are directly applicable to soil activation monitoring at other facilities. PMID- 9373070 TI - An analytically based model for the simultaneous leaching-chain decay of radionuclides from contaminated ground surface soil layers. AB - This paper describes an analytically based method for modeling the time-dependent radionuclide areal densities of contaminated soil surface layers when the soil experiences simultaneous leaching, surface erosion and chain radioactive decay. The model is used to predict time-dependent radionuclide areal densities in a volcanic ash blanket contaminated with spent nuclear fuel particles for the purpose of assessing the risks of radiation exposure from an extrusive volcanic event near a proposed high-level waste repository at Yucca Mountain. The method uses general analytical solutions (an expansion of the Bateman equations) for calculating serial decay, including non-radioactive decay loss terms, in order to calculate time-dependent radionuclide areal densities in the ash blanket. In the presented example, 43 "key" radionuclides are tracked and their concentrations in the blanket are displayed for a 10,000-y time period following the volcanic event. Although the analysis presented herein is for modeling contaminated volcanic ash blankets, the model would work equally well for modeling time dependent radionuclide contamination of land surfaces in, for example, site decommissioning. It is suggested that the general solutions for serial decay (with non-radioactive decay loss terms) can also be used to model the release of radionuclides from the waste packages under anticipated repository conditions. PMID- 9373072 TI - A practical neutron shielding code based on data base interpolation. AB - This work presents an interactive code, WRNS, based on data base interpolation for preliminary neutron shielding design. A wide-range data base of transmission factors is also generated for nine shielding materials having thicknesses up to 200 cm and for neutron energies up to 400 MeV by using adjoint calculations of a one-dimensional discrete ordinates code. In addition, calculation details of the interpolation code are clearly interpreted along with WRNS code applications presented as well. PMID- 9373073 TI - Direct determination of 90Sr and 147Pm in Chernobyl hot particles collected in Kiev using beta absorption method. AB - 59 hot particles were collected in Kiev, Ukraine, in 1987. All but one were prepared from a moss carpet of 360 cm2 area. Radionuclide composition of the hot particles was investigated by gamma-spectrometry and beta absorption method. Pure beta emitters 90Sr and 147Pm were determined in 25 hot particles measuring the beta absorption curves of the hot particles with an end-window Geiger-Muller counter and decomposing the curves in order to obtain the contributions of 90Sr and 147Pm to the total beta counting rate. All but one of the hot particles were found to be the debris of the fuel. The activity ratio 90Sr:l44Ce was 0.052 in good agreement with theoretical calculations on core inventories. This means that strontium behaved as a nonvolatile element in the process of the formation of the hot particles investigated. The activity ratio 147Pm:144Ce was 0.078 which is half of the theoretical result. Although 147Pm is considered to be a refractory nuclide, it seems that significant part of 147Pm went to the homogeneous fraction of the general fallout. The surface density of hot particles (of higher than about 50 Bq activity) was about 1,600 m(-2) and that of the activities of the nuclides 90Sr, 106Ru, 134Cs, 137Cs, 144Ce and 147Pm as components of hot particles was 12.2, 54.3, 5.9, 9.7, 234 and 18.3 kBq m(-2) (activity values counted for 26 April 1986), respectively, in downtown Kiev city in 1987. PMID- 9373071 TI - Determination of the volume activity concentration of alpha artificial radionuclides with alpha spectrometer. AB - This paper introduces a method to determine the volume activity concentration of alpha and/or beta artificial radionuclides in the environment and radon/thoron progeny background-compensation based on a Si surface-barrier detector. By measuring the alpha peak counts of 218Po and 214Po in two time intervals, the activity concentration of 218Po, 214Pb and 214Bi aerosol particles were determined; meanwhile, the total beta count of 214Pb and 214Bi aerosols was also calculated from their decay scheme. With the average equilibrium factor of thoron progeny in general environment, the alpha and beta counts of thoron progeny were approximately evaluated by 212Po alpha peak counts. The alpha count of transuranic aerosols was determined by subtracting the trail counts of radon/thoron progeny alpha peaks. The total count of beta artificial radionuclides was determined by subtracting the beta counts of radon/thoron progeny aerosol particles. In our preliminary experiments, if the radon progeny concentration is less than 15 Bq m(-3), the lower limit of detection of transuranics concentration is less than 0.1 Bq m(-3). Even if the radon progeny concentration is as high as 75 Bq m(-3), the lower limit of detection of total beta activity concentration of artificial nuclides aerosols is less than 1 Bq m( 3). PMID- 9373074 TI - A general algorithm for radioactive decay with branching and loss from a medium. AB - Many areas in the field of health physics require evaluation of the change of radionuclide quantity in a medium with time. A general solution to first-order compartmental models is presented in this paper for application to systems consisting of one physical medium that contains any number of radionuclide decay chain members. The general analytical solution to the problem is first described mathematically and then extended to four applications: 1) evaluation of the quantity of radionuclides as a function of time, 2) evaluation of the time integral of the quantity during a time period, 3) evaluation of the amount in a medium as a function of time following deposition at a constant rate, and 4) evaluation of the time integral of the amount in a medium after deposition at a constant rate for a time. The solution can be applied to any system involving constant physical transfers from the medium and radioactive chain decay with branching in the medium. The general solution is presented for quantities expressed in units of atoms and activity. Unlike many earlier mathematical solutions, this solution includes chain decay with branching explicitly in the equations. PMID- 9373075 TI - Response to C.S. Sims. PMID- 9373076 TI - State-dependent laryngomalacia. AB - We have observed 5 infants who demonstrate normal breathing when awake, but develop stridor while asleep. Flexible laryngoscopy in the awake state reveals either a normal larynx or redundancy of the aryepiglottic folds or arytenoid soft tissue without prolapse into the laryngeal inlet. When these children are sedated, however, the classic signs of laryngomalacia appear. Wet inspiratory stridor with concomitant supraglottic prolapse can be demonstrated by flexible videolaryngoscopy in this state. As these findings vary with level of consciousness, we have dubbed this condition "state-dependent" laryngomalacia. We believe the appearance and disappearance of classic laryngomalacia with changes in level of consciousness adds credence to the neurogenic theory of laryngomalacia. PMID- 9373077 TI - Partial cricotracheal resection with primary anastomosis in the pediatric age group. AB - The traditional approach to severe subglottic stenosis (SGS) in the pediatric age group is laryngotracheal reconstruction (LTR). This approach may be complex and multistaged, with variable and unpredictable success rates in the individual patient. Excellent results have been reported in adults who had severe SGS and underwent partial resection of the cricoid and primary thyrotracheal anastomosis. This procedure has not been widely reported in infants and children. We report our experience with this procedure in 16 pediatric patients with grade III or IV SGS. Eleven patients had multiple previous LTR operations. The preoperative evaluation, surgical techniques, postoperative care, complications, and final results are described and discussed. Fourteen patients were decannulated after the procedure, 1 patient needed a second open procedure prior to decannulation, and 1 patient with concomitant bronchopulmonary dysplasia remains cannulated, for an overall 94% decannulation rate. Fourteen patients have no limitation of respiration, and 1 patient has moderate exercise intolerance. The results of this series suggest that partial cricotracheal resection with primary anastomosis is a relatively safe and effective procedure for pediatric patients with severe SGS. PMID- 9373078 TI - Respiratory activity of the rat posterior cricoarytenoid muscle. AB - An anatomic and electrophysiological study of the rat posterior cricoarytenoid (PCA) muscle is described. The intramuscular nerve distribution of the PCA branch of the recurrent laryngeal nerve was demonstrated by a modified Sihler's stain. The nerve to the PCA was found to terminate in superior and inferior branches with a distribution that appeared to be confined to the PCA muscle. Electromyography (EMG) recordings of PCA muscle activity in anesthetized rats were obtained under stereotaxic control together with measurement of phrenic nerve discharge. A total of 151 recordings were made in 7 PCA muscles from 4 rats. Phasic inspiratory activity with a waveform similar to that of phrenic nerve discharge was found in 134 recordings, while a biphasic pattern with both inspiratory and post-inspiratory peaks was recorded from random sites within the PCA muscle on 17 occasions. The PCA EMG activity commenced 24.6 +/- 2.2 milliseconds (p < .0001) before phrenic nerve discharge. The results are in accord with findings of earlier studies that show that PCA muscle activity commences prior to inspiratory airflow and diaphragmatic muscle activity. The data suggest that PCA and diaphragm motoneurons share common or similar medullary pre-motoneurons. The earlier onset of PCA muscle activity may indicate a role for medullary pre-inspiratory neurons in initiating PCA activity. PMID- 9373079 TI - Reversibility of medialization laryngoplasty. An experimental study. AB - Medialization laryngoplasty has become a routine procedure for cases of unilateral vocal fold paralysis. In certain clinical situations, it may become desirable to reverse the procedure and remove the implant. This process was studied experimentally in eight dogs in a chronic model of induced canine phonation. A silicone polymer implant was inserted to medialize one normal vocal fold for a period of 1 month, after which it was removed. Motion of the cricoarytenoid (CA) joint and induced phonation were studied weekly while the implant was in place, and for another month following implant removal. Significant abnormalities were found even with this relatively short period of implantation. With the implant in place, impairment of CA joint mobility was found in seven of the eight dogs, precluding phonation. A dense fibrous capsule rapidly developed around the implant, making its removal technically difficult. Following implant removal, a gradual return to normal function was found in only three of the eight dogs. One of the animals had evidence of neural injury, while four had intact neural function but impaired mobility or fixation of the CA joint. Medialization laryngoplasty should not be considered a reversible procedure. The clinical implications of these findings are discussed. PMID- 9373080 TI - Surgical management of early-stage hypopharyngeal carcinoma. AB - There is little consensus regarding the extent of surgical ablation that is needed to attain cure in early-stage hypopharyngeal carcinoma (HPC). To determine effective surgical management of early-stage HPC, we retrospectively reviewed all cases of stage I or stage II HPC treated at our institution between 1970 and 1992. Of 305 patients identified with HPC, 50 (16%) had stage I (N = 13) or stage II (N = 37) cancer at diagnosis. Thirty-seven of the 50 (74%) underwent surgery alone or combined with preoperative or postoperative radiotherapy (RT). Patients were divided into three surgical groups. Group 1 underwent partial pharyngectomy (N = 9), group 2 underwent total laryngectomy and partial pharyngectomy (N = 17), and group 3 underwent total laryngopharyngectomy with cervical esophagectomy and reconstruction (N = 11). Overall and disease-specific survivals were determined from Kaplan-Meier survival analysis. Disease-free 5-year survival in stage I and II HPCs was 40.1%. Univariate analysis showed a statistically significant decrease in survival for patients undergoing partial pharyngectomy when compared with those undergoing more extensive procedures (p < .03). This was confirmed with multivariate loglogistic regression analysis (p < .03) correcting for confounding variables of site and RT. These data suggest that wide resection improves disease-free survival in patients with early-stage HPC. PMID- 9373081 TI - Slide tracheoplasty in the management of congenital tracheal stenosis. AB - Long-segment congenital tracheal stenosis (LSCTS) is a rare condition. Originally, it was felt to be uniformly fatal; however, advances in technique have made surgical repair and survival possible. Our objective is to report results and technique of slide tracheoplasty for the treatment of LSCTS in the context of the overall experience at the Children's Memorial Hospital in Chicago. We reviewed 37 cases of infants and children with LSCTS. Thirty of the 37 infants underwent surgical intervention. Slide tracheoplasty resulted in survival in 1 of 2 infants, and pericardial patch tracheoplasty resulted in survival in 21 of 28 (75%). Of the 30 patients who had surgical repair, 7 (23%) have died, and 1 has been lost to follow-up (3%). Follow-up has ranged from 6 months to 13 years. Slide tracheoplasty is a satisfactory adjunct to existing techniques. With early diagnosis and appropriate management of LSCTS, survival is possible in a majority of patients. PMID- 9373083 TI - Indications for, contraindications to, and interruption of craniofacial procedures. AB - In spite of increasing experience with skull base surgery, some of the guidelines for indications for operations may vary according to the institution. One-hundred two patients underwent craniofacial oncologic resections at our institution from 1982 to 1995. A retrospective analysis of the indications for and contraindications to these procedures was undertaken. The main indications for malignant tumors were skin lesions with direct invasion of the anterior or lateral skull base (69%) and nasal-paranasal sinus tumors (21%). The main indications for benign tumors were glomus lesions (26%), menigiomas (22%), and fibro-osseous lesions of the anterior skull base (19%). The main contraindications were extensive invasion of the central nervous system, invasion of the cavernous sinus and/or internal carotid artery by aggressive malignancies, and bilateral orbital invasion in a nonblind patient. Also, 6 patients had their procedures interrupted during craniotomy for several reasons - extensive central nervous system invasion (2 cases), bilateral orbital invasion (1), lack of brain retraction (1), lack of histologic diagnosis during the operation (1), and purulent discharge at the frontal sinus (1). Craniofacial oncologic operations are extensive surgical procedures that have to be properly indicated in order to obtain low levels of morbidity and mortality. The selection of cases is of paramount importance. In some instances, it seems advisable even to interrupt these operations in the first phase. PMID- 9373082 TI - Effect of antagonism at central nervous system M3 muscarinic receptors on laryngeal chemoresponse. AB - The laryngeal chemoresponse (LCR), comprising laryngeal adductor spasm, central apnea, and subsequent cardiovascular instability, is thought to be a factor in sudden infant death syndrome. A muscarinic subtype receptor, M3, appears to be involved in central respiratory drive and control. Both the duration of the LCR apnea and levels of M3 receptor messenger RNA in the brain stem change according to postnatal age. This study examined the effect of central nervous system antagonism at M3 receptors on the LCR with respect to animal age and dose of antagonist. Ten piglets in each of three age groups (group 1, 5 to 8 days; group 2, 18 to 21 days; and group 3, 40 to 43 days) received a series of four increasing doses of an M3 antagonist (p-fluoro-hexahydro-sila-diphenidol) by intracerebral ventricle injection. The LCR was evoked at baseline and after each dose of antagonist. An effect on susceptible animals (groups 1 and 2) was evident by the second antagonist dose, and persisted for the remainder of the experiment (2 hours). At completion of the experiment, mean apnea duration had decreased in group 1 (61%, p < .05), and group 2 (57%, p < .05), but was unchanged in group 3 (<10%, p not significant). Length of mean baseline apneas correlated directly with degree of apnea shortening. The reduction is not attributable to changes in arterial PO2 or PCO2 or baseline respiratory rate. These results support an age related influence on the LCR by M3 receptors in younger animals that decreases with maturation. PMID- 9373084 TI - Electrocochleographic evaluation of the guinea pig model of endolymphatic hydrops. AB - Electrocochleography (ECochG) was used to evaluate cochlear function in guinea pigs with experimentally induced endolymphatic hydrops (ELH) before and after osmotic dehydration with either glycerol or urea. We surgically induced ELH in the right ears of 9 guinea pigs, while the right ears of 6 guinea pigs received a sham operation. The left ears of the 15 animals constituted the normal group. Eight weeks after surgery, summating potential (SP) and action potential (AP) amplitudes were measured prior to and following the administration of glycerol or urea. The SPs and SP/AP ratios were reduced in all groups, with no significant differences among groups or between dehydrating agents. Some of the hydropic ears, however, did show an increased AP threshold and a recruitment effect. In measurements from 6 additional animals, serum osmolarity increased more with urea than with glycerol. The guinea pig model remains valuable for investigation of ELH, even though it differs in significant respects from ELH in humans. PMID- 9373085 TI - Angiosarcomas of the head and neck: clinical and pathologic characteristics. AB - Between 1974 and 1992, 32 patients with pathologically diagnosed angiosarcoma of the head and neck were evaluated at our institution. The primary treatment group consisted of 24 patients who had the initial diagnosis made or confirmed at our institution, and the other 8 patients formed the salvage group. There were 23 men and 9 women. The median age in the primary treatment group was 63 years (range 18 to 91 years). The overall median survival among the primary group patients was 4.8 years, and the 3-year survival was estimated to be 57% (95% confidence interval 39% to 84%). The median follow-up was 2.1 years (range 83 days to 9.7 years). Patients who had tumors less than 7.0 cm in diameter and tumors with invasion only to the subcutaneous tissues had better overall survival and longer time to first adverse event. Diploid DNA content was a significant favorable prognostic factor for time to first adverse event. Mitotic activity was of borderline significance with both end points. Patients who had tumors of less than 1.5 cm were treated successfully with surgery alone. Patients treated with combined surgery and radiotherapy also tended to do better. Because most patients in whom regional recurrences developed had tumors larger than 7.0 cm, we conclude that patients with tumors of this size may benefit from regional neck node dissection at the time of primary excision or from elective neck irradiation. PMID- 9373086 TI - Excision of rhinophyma with the carbon dioxide laser: a ten-year experience. AB - Rhinophyma is a disfiguring disease of the nasal skin, primarily affecting white men in the fifth to seventh decades of life. Hypertrophy of the sebaceous apparatus leads to an enlarged, erythematous nasal tip with comedones. Modalities of treatment include dermabrasion, freehand scalpel shave, cryosurgery, electrocautery, excision and closure with local flaps, and laser resection. A retrospective review of 18 patients treated with carbon dioxide laser excision of rhinophyma from 1983 to 1993 is presented. Discussion includes technique, postoperative care, complications, recurrence, operative blood loss, length of follow-up, time to complete reepithelialization, and pathologic findings. The carbon dioxide laser is a relatively safe, cosmetically efficacious, and curative method of treating rhinophyma. PMID- 9373087 TI - Transoral electromyographic recordings in botulinum toxin-injected rat larynges. AB - Objective assessment of muscle function following botulinum toxin injections in laryngeal muscles is difficult in human subjects. We developed a rat laryngeal model for the study of botulinum toxin injection. A new laryngoscopic technique has made it possible to observe the rat larynx endoscopically and to obtain electromyographic measurements during and after injection of toxin. The electromyographic interference pattern, fibrillation potentials, and vocal fold movement were used for analyzing dose and volume effects of injected toxin. We conclude that the lowest dosage able to produce the maximal duration of functional laryngeal impairment is 0.07 U in a volume of 0.4 microL. This model will enable us to obtain physiologic and histologic parameters that can be used to assess the selection of optimal treatment regimens with botulinum toxin for the treatment of patients with spasmodic dysphonia. PMID- 9373088 TI - Cervical necrotizing fasciitis. AB - Cervical necrotizing fasciitis (CNF) is an aggressive infection of the head and neck with high complication and mortality rates. Sixty-eight cases of CNF have been reported in the English-language literature. We present a series of 8 patients with CNF, including 5 men and 3 women ranging in age from 25 to 92 years. To the best of our knowledge, this is one of the largest case series reported. Six of the 8 patients had a predisposing odontogenic focus of infection. Four patients had mediastinal involvement. Two patients, both with significant comorbidity at the time of presentation, died of CNF. PMID- 9373090 TI - Cricoarytenoid joint effusion secondary to rheumatoid arthritis. PMID- 9373091 TI - Masticator space in nasopharyngeal carcinoma. PMID- 9373092 TI - Pretreatment pathologic prognostic factors in head and neck squamous cell carcinoma. AB - Squamous carcinomas of the head and neck region are a common problem for the otolaryngologist; surgeons are obliged to draw together disparate lines of evidence-from physical examination, pathology, and radiology-to plan optimal therapy for their patients. This article explores some of the ways in which pathologic analysis of a biopsy specimen in the past (determination of extent of invasion and degree of differentiation), present (including an analysis of the pattern of infiltration and the tumor' s DNA content), and, perhaps, the future (possibilities including cytogenetics and analysis of discrete steps in the cell cycle) plays a role in this process. PMID- 9373089 TI - Effect of cisplatin on the basement membrane anionic sites in the ampulla, macula, and stria vascularis of guinea pigs. AB - Our objective was to compare changes in the basement membrane anionic sites (BMAs) in the ampulla, macula, and stria vascularis following the infusion of cisplatin (CDDP). After CDDP was administered to anesthetized Hartley guinea pigs, the bony labyrinth was immersed in a solution of polyethyleneimine (PEI). The size and distribution of PEI particles associated with BMAs in the stria vascularis and in the dark cell and sensory cell areas of the vestibular labyrinth were determined by electron microscopy. A significant reduction in the number and size of PEI particles was observed on CDDP-treated strial vessels. The number and size of PEI particles on the basement membranes of the vestibular labyrinth did not differ from those in the control. Our findings suggest that the BMAs of the vestibular labyrinth were not significantly affected by the administration of a single dose of CDDP. PMID- 9373093 TI - Prism adaptation study. PMID- 9373094 TI - Refractive stability of LASIK. PMID- 9373095 TI - Ocular explosion after peribulbar anesthesia. PMID- 9373096 TI - Ocular explosion after peribulbar anesthesia. PMID- 9373097 TI - Unilateral retinoblastoma in an adult. PMID- 9373098 TI - Is Helicobacter pylori of interest to ophthalmologists? PMID- 9373099 TI - Early treatment of posterior retinopathy of prematurity: a controlled trial. AB - OBJECTIVE: The purpose of the study is to assess the possible benefits of early laser treatment for posterior retinopathy of prematurity (ROP) and to provide data concerning the natural history of posterior ROP. DESIGN: The study design was a prospective, multicenter, randomized trial. PARTICIPANTS: A total of 19 infants with prethreshold posterior ROP were studied. INTERVENTION: Randomization to immediate indirect laser photocoagulation or observation, with application of laser photocoagulation for those control eyes reaching threshold disease, was performed. MAIN OUTCOME MEASURES: Patients were assessed at 3 months and the anatomic outcome recorded along with any adverse treatment effects. RESULTS: An unfavorable structural outcome developed in 3 (16%) of 19 early treatment eyes compared with 3 (18%) of 17 for those treated only if threshold disease was reached. Of the 17 control eyes, 15 (88%) reached threshold disease. Progression to threshold occurred within 1 week in all but two eyes. All 12 control eyes with posterior ROP and any amount of extraretinal fibrovascular proliferation progressed to threshold disease. CONCLUSIONS: Although the number of patients studied is too small to reach statistical significance, the likelihood of a favorable outcome for eyes with prethreshold posterior ROP treated immediately with laser photocoagulation is comparable to that obtained by withholding treatment until threshold disease is reached. There is a high probability of progression from prethreshold to threshold disease, usually within 1 week or less. PMID- 9373100 TI - Results of bilateral cataract extraction with posterior chamber intraocular lens implantation in children. AB - OBJECTIVE: A retrospective study was undertaken to evaluate long-term anatomic and visual outcomes in eyes of children who underwent bilateral intraocular lens implantation. DESIGN: The study design was a review of medical records of 24 children operated on for bilateral cataracts and posterior chamber-intraocular lenses. PARTICIPANTS: Twenty-four children operated on for bilateral cataracts by 1 surgeon between February 1980 and February 1995 were studied. INTERVENTION: Cataract extraction with bilateral posterior chamber-intraocular lens implantation was performed. MAIN OUTCOME MEASURES: Best-corrected visual acuity, visual acuity without correction, intraocular pressure, manifest refraction, and any intraoperative or postoperative complications were measured. RESULTS: At last follow-up (mean follow-up, 50.8 months; range, 10-149 months), the intraocular lens was in good position and the intraocular pressure was normal without medication in all eyes. Four years after surgery, 79.2% (19 of 24) of first eyes achieved a best-corrected visual acuity of 20/40 or better compared to 66.7% (16 of 24) of second eyes. No eye had any loss in best-corrected visual acuity. In first eyes of 3- to 8-year olds at the time of surgery, 73.3% (11 of 15) achieved a spherical equivalent within 2 diopters of the intended at 4 years after surgery compared to 80% of second eyes. In the 9- to 18-year-old group, 88.9% (8 of 9) of first eyes and 100% of second eyes achieved a spherical equivalent within 2 diopters of the intended at 4 years after surgery. Intraoperative and postoperative complications were minimal. CONCLUSIONS: Long-term anatomic and visual results have been gratifying in this series of patients with bilateral implants. PMID- 9373101 TI - Theoretic refractive changes after lens implantation in childhood. AB - OBJECTIVE: Children with aphakia tend to have decreasing hyperopia as they grow older. No large study of the long-term refractive changes in children with pseudophakia has been published, although myopic shifts of greater than 10 diopters (D) have been reported. The authors used the refractions of children with aphakia and long follow-up to calculate the theoretic long-term refractive effects of pseudophakia. DESIGN: The study design was a chart review of eyes that underwent cataract surgery before age 10 with documented refractions for more than 7 years. PARTICIPANTS: Ninety-three eyes were studied. INTERVENTION: The initial aphakic refractions of the study eyes were used to calculate the intraocular lens (IOL) powers that would have been required to give emmetropia at cataract removal. The aphakic refractions at last follow-up were used to calculate the final pseudophakic refractions, and these were compared with the predictions of a logarithmic model of myopic shift. RESULTS: The mean follow-up time was 11 years. The median calculated pseudophakic refraction at last follow up was -6.6 D with a range of -36.3 to +2.9 D. Children who underwent surgery in the first 2 years of life had a substantially greater myopic shift than older children (P < 0.001) and a larger variance in this myopic shift (P < 0.001). The logarithmic model accurately predicted the final refraction within 3 D in 24% of eyes undergoing surgery before 2 years of age and in 77% of eyes undergoing surgery after this age. CONCLUSIONS: Pseudophakia in children is predicted to result in a large quantity of myopic shift, particularly in very young children. An IOL power chosen to leave a child initially hyperopic should lessen both the quantity of myopic shift and the extreme myopia that can result with growth. The surgeon who implants IOLs in young children must be prepared for a wide variation in long-term myopic shift. PMID- 9373102 TI - Myopic shift after intraocular lens implantation during childhood. AB - PURPOSE: The purpose of the study is to evaluate the myopic shift that occurs in children 3 to 9 years of age who undergo cataract extraction with primary intraocular lens (IOL) implantation. METHODS: A review of 18 children (mean, 6.3 +/- 0.5 year; range, 3-9 years) who had undergone primary IOL implantation was undertaken. Patients were observed for an average of 3.2 years. The initial and last postoperative refractive errors were compared. RESULTS: The mean myopic shift was -0.99 +/- 0.22 diopter (D) (median, 1.0 D) with a range of -3.25 to +0.38 D. The difference in the myopic shift of the children 3 to 5 years of age ( 0.94 +/- 0.30 D) was not significantly different from the myopic shift occurring in the children 6 to 9 years of age (-1.07 +/- 0.35 D). The myopic shift was less than 1.5 D in 70% of the eyes and only 3 eyes had a myopic shift greater than 2 D. Ninety percent of the children achieved a visual acuity of 20/40 or better in their pseudophakic eye or eyes. CONCLUSIONS: Although each patient should be evaluated on an individual basis, the authors recommend undercorrecting most children 3 to 9 years of age by 1 D from the IOL power predicted to achieve emmetropia. PMID- 9373103 TI - Comparison of visual acuity measured with Allen figures and Snellen letters using the B-VAT II monitor. AB - OBJECTIVE: Allen figure optotypes commonly are used to measure visual acuity in young children. Children with normal acuity measured with Allen figures sometimes are found to have unsuspected amblyopia that is detected when they are tested with Snellen letters. The correlation between visual acuities measured with these two optotype charts has not been well studied. The authors compared visual acuities measured with Allen figure and Snellen letter optotypes using the Mentor B-VAT II monitor. DESIGN: The study design was a nonrandomized, comparative clinical trial. PARTICIPANTS: The study was composed of 12 adult subjects. INTERVENTION: Visual acuities were measured using both Allen figure and Snellen letter optotypes using the B-VAT II monitor. The images were progressively blurred using plus lenses. MAIN OUTCOME MEASURES: Visual acuity was measured. RESULTS: At visual acuity levels of 20/60 or better, Allen figure testing averaged 1.5 lines better than Snellen letter testing; between 20/70 and 20/200 visual acuities, the difference was 2.5 lines. CONCLUSIONS: Allen figure testing with the B-VAT II monitor overestimates visual acuity compared with testing with Snellen letters. This appears to result primarily from the construction of the optotypes. This discrepancy should be considered when visual acuity is measured in young children. PMID- 9373104 TI - Botulinum toxin management of childhood intermittent exotropia. AB - OBJECTIVE: Intermittent exotropia is a common form of childhood strabismus that has a late onset and presents a difficult and frustrating management dilemma. Surgical treatments have a high recurrence rate, and multiple surgeries often are required to achieve a desirable motor outcome. This study presents long-term observations on the use of botulinum toxin for the treatment of intermittent exotropia in children. DESIGN: This study is a nonrandomized, case-controlled study of consecutive pediatric patients who had intermittent exotropia. PARTICIPANTS: Thirty-two neurologically normal children ranging from 3 to 144 months in age were diagnosed with intermittent exotropia with a minimum distance deviation of 15 prism diopters (PD). INTERVENTION: Simultaneous bilateral injections of 2.5 units botulinum toxin type A were made into the lateral rectus muscles with the patient receiving nitrous oxide-ethrane inhalation anesthesia. Patients were observed for 12 to 44 months after the initial injection. MAIN OUTCOME MEASURES: A satisfactory outcome was considered to be stable binocular alignment of the eyes to an orthophoric range of +/-10 PD. RESULTS: Bilateral lateral rectus muscle injections of botulinum toxin were effective in reducing the mean preinjection deviation of -29 PD to an average exotropic angle of -6 PD. Stable orthophoria (+/-10 PD) was achieved in 22 patients (69%). Overall, male patients required significantly fewer injections than did female patients. All patients between 24 and 56 months of age, irrespective of gender, required only a single bilateral injection to achieve a favorable motor outcome. CONCLUSIONS: Botulinum toxin is at least as effective as surgical outcomes reported previously for the treatment of intermittent exotropia in children. This treatment method is particularly effective in children between 2 and 4.5 years of age irrespective of the initial strabismic angle and is not associated with any secondary abnormalities. PMID- 9373105 TI - Epidemic Bacillus endophthalmitis after cataract surgery I: acute presentation and outcome. AB - OBJECTIVE: The purpose of the study is to report the clinical outcome of acute Bacillus endophthalmitis after cataract surgery. DESIGN: The study design is a cohort study. PARTICIPANTS: Fourteen eyes of 14 patients with epidemic acute postoperative inflammation after exposure to bacteria-contaminated viscoelastic material were studied. INTERVENTION: Three patients with milder clinical presentations were treated without vitrectomy or antibiotics. Eleven patients with more severe infection were treated with vitrectomy as well as intravitreous and topical fortified antibiotics. MAIN OUTCOME MEASURES: Final visual acuities were obtained in all 14 study patients. Results of microbiologic studies of aqueous and vitreous specimens from 11 vitrectomized eyes also were analyzed. RESULTS: One patient with late presentation had severe inflammation and had phthisis bulbi develop with no light perception. The remaining 13 patients had successful resolution of inflammation after treatment by 1 month of follow-up. Twelve of these 13 patients, including 1 nonvitrectomized patient, had final visual acuities of 20/100 or better at 6 months' follow-up. Six patients, including two patients with nonvitrectomized eyes, had outcomes of 20/40 or better visual acuity. Bacillus species were grown from all 11 (100%) vitreous and 7 (88%) of 8 aqueous specimens obtained from vitrectomized patients, as well as from the contaminated viscoelastic material remaining in the operating room. CONCLUSIONS: Postoperative Bacillus endophthalmitis need not result in poor outcome. Results depend on factors including bacterial load, specific bacterial species, timing of treatment, and immune status of the patient. PMID- 9373106 TI - Choroidal hemangiomas: visual and anatomic results of treatment by photocoagulation or radiation therapy. AB - PURPOSE: Choroidal hemangioma is a benign hamartoma that causes accumulation of subretinal fluid and resultant visual loss. Although photocoagulation can result in resolution of subretinal fluid, some have found that recurrence is common and final visual acuity often is poor. The purpose of this study is to evaluate the visual and anatomic results of radiation therapy and photocoagulation in treating patients with visual loss from choroidal hemangiomas. METHODS: A retrospective review was performed of patients with circumscribed choroidal hemangiomas (CCH) or diffuse choroidal hemangiomas (DCH) treated for visual loss caused by accumulation of subretinal fluid. Of 23 patients with CCH, 13 were treated by photocoagulation, 8 by plaque brachytherapy, and 2 by lens-sparing external beam radiation therapy (LSRT). All five patients with DCH were treated by LSRT. RESULTS: Of patients with CCH treated by brachytherapy, six (75%) of eight had visual acuity of 6/12 or better at 1 year and 8 (100%) of 8 had no subretinal fluid. Of patients with CCH treated by photocoagulation, 5 (38%) of 13 had visual acuity of 6/12 or better at 1 year and 6 (46%) of 13 had no subretinal fluid. Of patients with CCH treated by LSRT, none of two had visual acuity of 6/12 or better at 1 year and one of two had no subretinal fluid. Of the five patients with DCH treated by LSRT, all had complete resolution of subretinal fluid. Two had marked visual improvement and in the other three, vision was stabilized. CONCLUSIONS: Plaque brachytherapy is an effective alternative to photocoagulation for treatment of subretinal fluid caused by CCH. Lens-sparing external beam radiation therapy is effective treatment in patients with DCH. PMID- 9373107 TI - Efficacy of proton therapy in circumscribed choroidal hemangiomas associated with serious retinal detachment. AB - OBJECTIVE: The purpose of the study is to evaluate the efficacy and safety of proton therapy in complicated circumscribed choroidal hemangiomas. DESIGN: The study design was a retrospective review. PARTICIPANTS: Studied were 13 patients (13 eyes) who had circumscribed choroidal hemangioma associated with serous retinal detachment. Of these, four eyes previously underwent laser unsuccessfully. INTERVENTION: Proton therapy including a total dose of 30 Cobalt Gray-Equivalent was administered to each eye. MAIN OUTCOME MEASURES: Patients were controlled for initial and final best-corrected visual acuity, slit-lamp examination, intraocular pressure, fundus examination, fluorescein angiography, and tumor thickness on B-scan ultrasonography. RESULTS: The mean follow-up period was 26 months (range, 9-48 months). Retinal reattachment was obtained in all cases after a mean period of 52 days. The tumor height decreased in all cases. Visual acuity improved to two lines or more in eight eyes (62%) and reached 20/200 or more in nine eyes (69%). No radiation complication was detected during follow-up. CONCLUSIONS: Proton radiation seems to be effective and safe in the management of choroidal hemangioma associated with serous retinal detachment. It may be useful when photocoagulation can not be performed. PMID- 9373108 TI - Metastatic risk for distinct patterns of postirradiation local recurrence of posterior uveal melanoma. AB - OBJECTIVE: The purpose of the study is to compare the prognostic significance of horizontal/marginal versus vertical/diffuse patterns of postirradiation local recurrence of posterior uveal melanoma. DESIGN: The study design was a nonrandomized, retrospective clinical study. Semiparametric and nonparametric statistical techniques were used. PARTICIPANTS: Seven hundred sixty-six posterior uveal melanoma patients were studied. INTERVENTION: Either iodine-125 plaque or helium ion radiation therapy was performed. MAIN OUTCOME MEASURES: Local tumor recurrence and systemic metastasis were measured. RESULTS: Local tumor recurrence was detected in 66 (8.6%) of 766 irradiated tumors. The 5-year actuarial rate of local recurrence was 10%. The recurrence pattem was horizontal/marginal in 27 patients (41%) and vertical/diffuse in 39 patients (59%). Systemic metastasis was detected in 5 patients (19%) with horizontal/marginal recurrence and in 19 patients (49%) with vertical/diffuse recurrence. After known metastatic risk factors were controlled, the relative risk for metastasis was 2.2 for horizontal/marginal recurrence and 5.1 for vertical/diffuse recurrence (P = 0.05). The actuarial rate of systemic metastasis was 2.9% per year for all patients, 6.3% per year for patients with horizontal/marginal recurrence, and 15.5% per year for patients with vertical/diffuse recurrence. CONCLUSIONS: Postirradiation local recurrence of posterior uveal melanoma is a risk factor for systemic metastasis. Vertical/diffuse recurrences may be associated more strongly with metastatic disease than horizontal/marginal recurrences. PMID- 9373109 TI - Microwave thermoradiotherapy for uveal melanoma: results of a 10-year study. AB - OBJECTIVE: The purpose of the study is to evaluate clinically the use of microwave-heating (hyperthermia) as an adjuvant to ophthalmic plaque irradiation for treatment of patients with uveal melanoma. Hyperthermia was also used as a radiation sensitizer, allowing for significant dose reductions during ophthalmic plaque radiation therapy. PARTICIPANTS: In this case series, 48 patients were treated with microwave plaque thermotherapy for uveal melanoma. INTERVENTION: Microwave treatment, which involved affixing a miniature microwave dish antenna on the sclera beneath the tumor after completion of plaque brachytherapy, was performed. During hyperthermia treatment, the tumor's apex was targeted to receive a minimum of 42 degrees C for a 45-minute duration. A subset of 38 (79%) were given reduced apical doses of ophthalmic plaque radiation (radioactive isotope of iodine [125I] or palladium-103 [103Pd]) to an average of 52.6 Gy. MAIN OUTCOME PARAMETERS: Patients were evaluated for visual function, microwave toxicity, radiation oculopathy, eye retention, local tumor control, and metastatic disease. RESULTS: Patients have been observed for up to 10 years and for an average of 60 months (5 years). To date, there have been 3 cases of postoperative tumor enlargement (growth) for a 93.8% local control rate. Two patients were lost to follow-up. Seven eyes have been enucleated: three due to neovascular glaucoma, one due to uveitic neovascular glaucoma, and three due to progressive tumor enlargement. Although 15 patients have died, only 4 deaths were because of metastatic choroidal melanoma. Of the original 48 patients, 33 (69%) have maintained within 2 lines or have better than their preoperative visual acuity. Side effects attributable to heating have included decreased intraocular pressure without hypotony as well as chorioretinal scar formation within and around the targeted zone. CONCLUSIONS: The results of this series suggest that adjuvant microwave thermotherapy can be used with reduced doses of ophthalmic plaque radiation therapy to control the growth of uveal melanomas. Although the incidence of neovascular glaucoma, enucleation, and tumor regrowth is comparable to that of other series evaluating radiation alone, the visual acuities of microwave plaque thermotherapy-treated eyes were found to be superior. PMID- 9373110 TI - The relation of cardiovascular disease and its risk factors to the 5-year incidence of age-related maculopathy: the Beaver Dam Eye Study. AB - OBJECTIVE: The purpose of the study is to examine the association between cardiovascular disease and its risk factors and the incidence of age-related maculopathy. PARTICIPANTS: A population of 3583 adults (range, 43-86 years of age at baseline) living in Beaver Dam, Wisconsin, was studied at baseline and 5 years later. METHODS: Standardized protocols for physical examination, blood collection, administration of a questionnaire, and stereoscopic color fundus photography to determine age-related maculopathy were used. Standard univariate and multivariate analyses were performed. MAIN OUTCOME MEASURES: Incidence and progression of age-related maculopathy were measured. RESULTS: After controlling for age and gender, the authors found both higher systolic blood pressure (odds ratio [OR] per 10 mmHg, 1.16; 95% confidence interval [CI] 1.05, 1.27) and uncontrolled treated hypertension (OR 1.98, 95% CI 1.00, 3.94) were related to the incidence of retinal pigment epithelial depigmentation. After controlling for age and gender, the authors found that both blood pressure and uncontrolled treated hypertension were not significantly associated with an increased risk of having exudative macular degeneration develop (for systolic blood pressure, OR 1.18, 95% CI 0.95, 1.45; for uncontrolled treated hypertension, OR 2.10, 95% CI 0.54, 8.11). After controlling for age and gender, the authors found higher pulse pressure was significantly associated with increased incidence of retinal pigment epithelial depigmentation (OR per 10 mmHg 1.27, 95% CI 1.14, 1.42) and exudative macular degeneration (OR per 10 mmHg 1.29, 95% CI 1.02, 1.65). These relations remained significant after controlling for other risk factors in multivariable analyses. CONCLUSIONS: These findings indicate modest relations between higher pulse pressure (a presumed indicator of atherosclerotic vascular disease) and uncontrolled hypertension with increased 5-year incidence of retinal pigment epithelial depigmentation. Overall, however, data from this study show neither consistent nor strong relations between cardiovascular disease and most of its risk factors with the incidence of lesions associated with age-related maculopathy. PMID- 9373111 TI - Indocyanine green angiography of multifocal choroiditis. AB - PURPOSE: The purpose of the study is to determine indocyanine green (ICG) angiographic characteristics of patients with multifocal choroiditis (MC) and to identify features that may assist in the differentiation of MC from other ocular inflammatory diseases. METHODS: After complete ophthalmologic examination, fluorescein angiography and ICG angiography were performed in a series of 14 patients with MC. The ICG findings were then correlated with the clinical and fluorescein angiographic appearance of these patients to determine specific characteristics and distinguishing features of the entity. These findings then were compared with those of angiographic patterns observed in patients with ocular histoplasmosis syndrome to determine whether differentiating features could be identified. RESULTS: Fourteen (50%) of the 28 eyes were found to have large hypofluorescent spots in the posterior pole on ICG angiography, which, in most cases, did not correspond to clinically or fluorescein angiographically detectable lesions. Seventeen (61%) had smaller hypofluorescent lesions (approximately 50 pm in size) in the posterior pole on the ICG study. In seven eyes exhibiting enlarged blind spots on visual field testing, ICG angiography showed confluent hypofluorescence surrounding the optic nerve. The ICG angiogram was found useful in evaluating the natural course in two patients with MC as well as a response to oral prednisone therapy in four others. The ICG angiographic findings differed from those seen in patients with ocular histoplasmosis. CONCLUSIONS: Indocyanine green angiography can provide information that is not detectable by clinical or fluorescein angiographic examination in patients with MC. This information may prove useful in differentiating this condition from the ocular histoplasmosis syndrome, provide a better understanding of the natural course and progression of the disease, and provide a potential adjunct in the clinical evaluation of patients undergoing therapeutic regimens for active inflammatory lesions. PMID- 9373112 TI - Peripheral multifocal chorioretinitis: a distinct clinical entity? AB - OBJECTIVE: The purpose of the study is to delineate the clinical features, complications, visual prognosis, and associated systemic diseases of peripheral multifocal chorioretinitis. DESIGN: The study design was a retrospective study. PARTICIPANTS: Of 828 patients with uveitis, 53 patients (6.4%) fulfilled all 3 of the following criteria: (1) the presence of multiple (>10), small, round, punched out lesions in the peripheral retina; (2) the absence of central chorioretinal lesions; and (3) an associated intraocular inflammatory reaction. RESULTS: The majority of patients were elderly white females with bilateral ocular involvement. The presenting symptoms consisted of vitreitis and/or iritis, papillitis, and numerous retinal punched-out lesions in the periphery. On initial examination, the complications included cystoid macular edema (CME) (48%), glaucoma (25%), and cataracts (19%), resulting in a mean visual acuity of 20/80. After more than 2 years of follow-up, CME was found in 72% and cataract in 62% of the affected eyes. Submacular neovascularization never developed. The final mean visual acuity was 20/60; this was mainly dependent on the presence of CME (eyes with CME; visual acuity was 20/80, eyes without CME; visual acuity was 20/50). In 25% of patients, an association with sarcoidosis was observed (histologic and radiologic diagnoses), and an additional 29% of patients had elevated serum angiotensin-converting enzyme levels. CONCLUSIONS: Within the spectrum of multifocal chorioretinitis, the authors have defined a distinct clinical entity of peripheral multifocal chorioretinitis. The recognition of this clinical entity may be valuable because of its specific symptoms, prognosis, and association with sarcoidosis. PMID- 9373113 TI - Adverse events and autopsy findings after intravitreous cidofovir (HPMPC) therapy in patients with acquired immune deficiency syndrome (AIDS). AB - OBJECTIVE: The purpose of the study is to evaluate the adverse events and autopsy findings in a series of consecutive 20-microg intravitreous cidofovir injections at a single institution. DESIGN: The study design was a nonrandomized, consecutive case series. PARTICIPANTS: Seventy-six patients with acquired immune deficiency syndrome with cytomegalovirus retinitis were studied prospectively. Sixty-three patients had 1 month's follow-up or longer, and this comprised the study group. In addition, histopathologic findings from 18 eyes of 9 patients were studied at autopsy. INTERVENTION: A total of 296 injections of 20 microg cidofovir were given in 115 eyes. Sixty-three patients who had 246 injections in 93 eyes had 1 month's follow-up or longer for the evaluation of adverse events. MAIN OUTCOME MEASURES: Postinjection chronic hypotony associated with permanent visual loss, transient hypotony, iritis, and its long-term sequela (posterior synechia and cataract, retinal detachment, extraocular cytomegalovirus involvement) were the outcomes of interest in this study. Additionally, light and electron microscopic studies of human eyes were performed. RESULTS: The most severe adverse event was postinjection chronic hypotony. This phenomenon was associated with permanent visual loss. This was observed in 1% of the injections and 3% of the eyes of the patients (95% confidence interval, 0%-6%). Transient hypotony associated with mild-to-moderate visual loss developed in 14%, but vision recovered to baseline levels in these eyes subsequently. Analysis showed that transient hypotony in the injected eye could predict postinjection chronic hypotony in the fellow eye (two-tailed Fisher's exact test, P = 0.02). The incidence of iritis was 32%; posterior synechia and cataract were the long-term sequela of the iritis and developed in 19% and 11% of the eyes, respectively. The incidence of retinal detachment was lower (6%). Histopathologic evaluation of the eyes showed mild-to-moderate atrophy of the nonpigmented epithelium of the ciliary body and no other evidence of intraocular toxicity. CONCLUSIONS: The most serious adverse event was postinjection chronic hypotony, which occurred in 3% of eyes. Episodes of transient hypotony appear to indicate that the fellow eye was predisposed to chronic hypotony. Therefore, it may be prudent to give intravitreous injections at least 2 weeks apart in the fellow eye to evaluate the clinical response of the injected eye. PMID- 9373114 TI - Grid laser photocoagulation for macular edema in bilateral juxtafoveal telangiectasis. AB - OBJECTIVE: The purpose of the study is to report the efficacy of laser photocoagulation treatment for macular edema in bilateral juxtafoveal telangiectasis (BJT). DESIGN: The study design was a retrospective, clinical study. PARTICIPANTS: The authors observed 14 patients with BJT, studying the visual acuities and retinal changes of treated and untreated eyes. MAIN OUTCOME MEASURES: Visual acuity, presence of macular edema, and associated retinal findings were measured. RESULTS: Of 28 eyes, 10 (8 patients) received 15 laser photocoagulation treatments for macular edema. Neither treated nor untreated eyes had visual improvement of two or more lines. After treatment, five eyes (50%) had increased retinal vascular distortion develop, three (30%) had new draining retinal venules, five (50%) had intraretinal fibrovascular tissues, and four (40%) had retinal and preretinal hemorrhages develop. CONCLUSIONS: Grid laser photocoagulation therapy for macular edema in patients with BJT appears to neither improve nor stabilize long-term visual acuity. In addition, treatment is associated with retinal pigment epithelial changes, increased postoperative retinal vascular distortion, postoperative vascularized retinal scars, and postoperative retinal hemorrhages. These changes, however, do not appear to cause a further loss of vision. PMID- 9373115 TI - Tissue plasminogen activator-assisted surgical excision of subfoveal choroidal neovascularization in age-related macular degeneration: a randomized, double masked trial. AB - OBJECTIVE: To determine whether lysing subretinal fibrin with tissue plasminogen activator (t-PA) before excising subfoveal choroidal neovascularization improves visual acuity in patients with age-related macular degeneration. DESIGN: Randomized, double-masked trial. PARTICIPANTS: Eighty eyes of 80 patients with subfoveal choroidal neovascularization secondary to age-related macular degeneration were studied. INTERVENTION: Each eye underwent pars plana vitrectomy and received a subretinal injection of t-PA or balanced salt solution (BSS) before the neovascular membrane was excised. Preoperative and postoperative protocol refraction, ophthalmic examination, color photography, and fluorescein angiography were performed in all 80 eyes. MAIN OUTCOME MEASURES: Visual acuity and fluorescein angiographic evidence of leakage after 1 year. RESULTS: Visual acuity did not differ between the t-PA group (n = 40) and the BSS group (n = 40), and median best-corrected visual acuity was 20/320 for both groups (P = 0.38). Changes in visual acuity from baseline were also equal, with a median loss of 1 line in each group (P = 0.78). Patients whose initial visual acuity was 20/250 or less were more likely to improve by 2 or more lines (P = 0.01) and less likely to lose 2 or more lines (P < 0.001). Patients with choroidal neovascularization of at least 4 disc areas were more likely to improve by 2 or more lines (P = 0.02) and less likely to lose 2 or more lines (P < 0.001). After 1 year, choroidal neovascularization was present in seven of the t-PA eyes and in eight of the BSS eyes (P = 0.78). CONCLUSIONS: With current surgical techniques, the use of t-PA before surgical excision of subfoveal choroidal neovascularization is of no visual or anatomic benefit to patients with age-related macular degeneration. PMID- 9373116 TI - Pneumocystis carinii infection of the conjunctiva in a patient with acquired immune deficiency syndrome. AB - BACKGROUND: Ocular disease, especially the development of choroidal lesions, is a known extrapulmonary manifestation of Pneumocystis carinii infection in the acquired immune deficiency syndrome (AIDS). To our knowledge, conjunctival involvement due to P. carinii has not been described previously. METHODS: The authors describe a 33-year-old homosexual male with AIDS in whom a large placoid, white lesion developed involving the tarsal conjunctiva of the right upper lid. Conjunctival malignancy was suspected and biopsies and swabs were taken. At this time, the patient had been receiving monthly aerosolized pentamidine prophylaxis for 18 months, and there was neither a history of pneumonia nor any clinical signs of disseminated infection due to P. carinii. RESULTS: Histopathologic examination results of the conjunctival biopsy specimen showed a necrotic, frothy tissue surrounded by activated fibroblasts. Within this material, Gomori methenamine silver stains showed numerous round and cup-like cysts of P. carinii, confirming the diagnosis that had already been obtained by an indirect fluorescent-antibody stain of a conjunctival smear specimen. CONCLUSIONS: The presence of white placoid conjunctival lesions in a patient with AIDS may indicate an infection due to P. carinii. Conjunctival disease due to P. carinii widens the spectrum of AIDS-associated ophthalmic pneumocystosis. PMID- 9373117 TI - Periocular necrotizing fasciitis: a review of five cases. AB - OBJECTIVE: The purpose of the study is to display a spectrum of clinical presentations of periocular necrotizing fasciitis caused by group A streptococci and to discuss recent trends and treatment of this disease. DESIGN AND INTERVENTION: A case series of five patients (four female and one male) was seen between July 1990 and January 1995 in four university centers. All had clinical evidence of periocular necrotizing fasciitis and grew group A streptococci on wound cultures or had serologic evidence of streptococcal infection. Details of patient presentation, treatment, and outcome are examined. RESULTS: The five patients showed a spectrum of clinical severity from a necrotizing infection confined to the eyelid to a potentially fatal, severe shock-like syndrome characterized by sepsis and multiorgan system failure. A history of trauma often was absent. Patients were treated successfully by a combination of appropriate antibiotics and surgical debridement. CONCLUSIONS: Group A streptococci can cause severe necrotizing infections of the eyelids. Early recognition and prompt treatment can be essential to these patients' survival. PMID- 9373118 TI - Ocular rosacea: patient characteristics and follow-up. AB - PURPOSE: The purpose of this report is to review the presenting symptoms and signs, treatment regimens used, complications encountered, and outcome in a cohort of patients with ocular rosacea. METHODS: The medical records of 131 patients with a diagnosis of ocular rosacea were reviewed retrospectively. Data were entered in a tabulated form, and a descriptive analysis was performed. RESULTS: The age range at presentation was between 23 and 85 years (mean, 56 years). Cutaneous manifestations of rosacea were present in 112 of the patients at their first visit. The most common presenting symptoms were foreign body sensation and burning, and the most common signs were telangiectasia and irregularity of lid margins, and meibomian gland dysfunction. Thirteen patients had decreased visual acuity at the time of presentation due to corneal complications. Six of these patients required penetrating keratoplasty during the course of their disease. Seven patients had severe cicatrizing conjunctivitis at the time of referral. One hundred thirteen patients were treated with oral tetracycline derivatives. Seven patients were left with visual acuity less than 20/400, and one patient underwent enucleation for corneal perforation and endophthalmitis. CONCLUSIONS: Ocular rosacea is a common disease involving the skin and the eyes. It is widely underdiagnosed by many ophthalmologists despite the blinding potential. Successful therapy requires a multidisciplinary approach. PMID- 9373119 TI - Inflammatory cytokines in the tears of patients with ocular rosacea. AB - OBJECTIVE: The purpose of the study is to compare tear fluid concentrations of interleukin-1alpha (IL-1alpha), tumor necrosis factor-alpha (TNF-alpha), and epidermal growth factor (EGF) in ocular rosacea with those in control subjects and to examine the relation between tear functions, such as production and clearance rate, and the concentrations of cytokines in tear fluid. PARTICIPANTS AND INTERVENTION: Fourteen patients with severe meibomian gland disease, facial rosacea, and symptoms of ocular irritation were examined for ocular surface disease, tear production, and tear clearance rate (TCR). Twelve control subjects, frequency-matched for age, and 15 ideal normal subjects with no ocular symptoms and normal tear function were assessed using the same parameters. Minimally stimulated tear samples (20 microl) were drawn from each subject and analyzed using a sandwich enzyme-linked immunosorbent assay to detect IL-1alpha, TNF alpha, and EGF. RESULTS: Tear IL-1alpha concentration was significantly higher in patients with rosacea than in age-matched (P = 0.003) and ideal control subjects (P < 0.001). Tumor necrosis factor-alpha was not detected in patients or control subjects, indicating levels of less than 10 pg/ml. Epidermal growth factor was not significantly higher in patients with rosacea than in age-matched control subjects. Tear turnover LN(TCR) was lower in patients with rosacea than in both age-matched (P = 0.048) and ideal control subjects (P = 0.002). Schirmer I scores were statistically lower in patients with rosacea than in ideal control subjects (P = 0.013), but not age-matched control subjects. Interleukin-1alpha was correlated inversely with LN(TCR) (r= -0.58, P < 0.0001) and Schirmer I (r = 0.39, P = 0.012). CONCLUSIONS: Concentrations of IL-1alpha are present in normal tears but are elevated in ocular rosacea, whereas TNF-alpha is not present in either case. The reduced tear turnover, LN(TCR), its inverse correlation with IL 1alpha, and the absence of TNF-alpha in the tears of these patients suggest that the increased concentration of IL-1alpha observed may be largely because of clearance failure of cytokine normally produced at the ocular surface. PMID- 9373120 TI - Clinical and radiologic lacrimal testing in patients with epiphora. AB - OBJECTIVE: The purpose of the study is to assess the strengths and weaknesses of selected clinical and radiologic lacrimal tests in patients with epiphora. DESIGN: The study design was a prospective clinical trial. PARTICIPANTS: Fifteen patients with epiphora (N = 27 eyes) were studied. METHODS: All patients underwent Jones testing, the dye disappearance test, canalicular probing, lacrimal scintigraphy, and macrodacryocystography. MAIN OUTCOME MEASURES: The dye disappearance test was graded individually by three ophthalmologists. Lacrimal scintigraphy and macrodacryocystography were evaluated by a nuclear medicine specialist and a radiologist, respectively. A panel of three ophthalmologists evaluated the data using a scoring system that relied on the preponderance of evidence to arrive at a final assessment. RESULTS: When the Jones I test results were negative (dye recovered from the nose), the epiphora was always from hypersecretion. When the Jones I test results were positive (no dye recovered from the nose), obstruction was not always present. When the dye disappearance test results were strongly abnormal, obstruction was always present. In contrast, when the dye disappearance test results were normal, the lacrimal drainage system was not always patent. Canalicular probing was more reliable than scintigraphy in identifying canalicular obstruction. Marked stenosis of the sac or duct on dacryocystography essentially confirmed nasolacrimal outflow obstruction; however, with the authors' technique, a normal study was found in some patients with functional or partial obstruction. CONCLUSIONS: More than one lacrimal test may be required for a definitive diagnosis in patients with epiphora due to partial or functional nasolacrimal outflow obstruction. PMID- 9373121 TI - Clinically suspected primary acquired nasolacrimal duct obstruction: clinicopathologic review of 150 patients. AB - PURPOSE: The incidence of lacrimal sac pathology in patients with clinically suspected primary acquired nasolacrimal duct obstruction is unknown. This is an important issue when considering the potential risk of either conservative nonsurgical management or laser dacryocystorhinostomy, neither of which permits direct visualization and biopsy of the lacrimal outflow apparatus. METHODS: A total of 162 lacrimal sac biopsy specimens were obtained in 150 consecutive patients undergoing external or endonasal dacryocystorhinostomy for clinical primary acquired nasolacrimal duct obstruction from January 1992 to October 1994. RESULTS: A total of 147 patients (98%) had histopathologic findings consistent with inflammation or fibrosis of the lacrimal sac or both. In the remaining three patients, abnormalities included sarcoid granuloma (one patient), oncocytoma (one patient), and lymphoma (one patient). CONCLUSIONS: The incidence of significant pathology of the lacrimal sac in clinically suspected primary acquired nasolacrimal duct obstruction is low. However, these cases can be identified correctly only by routine biopsy of the lacrimal sac during dacryocystorhinostomy. PMID- 9373122 TI - Long-term contact lens wear induces a corneal degeneration with microdot deposits in the corneal stroma. AB - OBJECTIVE: Confocal in vivo real-time microscopy was applied to study the corneal morphology in long-term contact lens wearers. DESIGN: In a cross-sectional study, patients with a history of long-term contact lens wear underwent corneal confocal microscopy. The authors investigated 13 patients with a history of up to 26 years of soft contact lens wear, 11 patients with a history of up to 25 years of rigid gas permeable contact lens wear, and a control group of 29 normal subjects without a history of contact lens wear. INTERVENTION: Scanning slit-confocal microscopy was performed with a 50x/1.0 NA water immersion objective. Corneal optical sections were recorded in real time without further digital processing and reviewed frame by frame. MAIN OUTCOME MEASURES: Video frames selected from all corneal layers were evaluated qualitatively. The new finding of panstromal microdot deposits was quantitated in a scoring system ranging from 0 to 4+. Corneal endothelial cell densities were counted with the fixed frame technique. RESULTS: Epithelial microcystic changes and alterations of endothelial cell morphology were found to a variable extent as described previously. A new finding was there were highly reflective panstromal microdot deposits in the corneal stroma. For this new disease, a scoring system ranging from 0 to 4+ was established. In the control group, 0 of 29 patients had stromal microdot deposits. In the soft contact lens group, 13 of 13 patients had panstromal microdot deposits with a mean score of 3.1 (range, 1-4), and in the hard contact lens group, 11 of 11 had a mean score of 1.9 (range, 1-4) for corneal microdot deposits. CONCLUSIONS: With confocal microscopy, a new type of chronic stromal change has been observed in all subjects with long-term contact lens wear. Because subjects with soft contact lens wear had a more pronounced corneal degeneration than did subjects with gas permeable lenses, the authors assume the deposits to be induced by chronic hypoxia. The condition of stromal microdot degeneration as observed with confocal microscopy may be the early stage of a significant corneal disease, which eventually may affect large numbers of patients after decades of contact lens wear. PMID- 9373123 TI - The utility of culturing corneal ulcers in a tertiary referral center versus a general ophthalmology clinic. AB - OBJECTIVE: The purpose of the study is to compare the utility of culturing corneal ulcers in a tertiary referral clinic and a general ophthalmology clinic. DESIGN: A retrospective review of medical and microbiologic records was performed. PARTICIPANTS: One hundred fifty-seven patients with corneal ulcers were included in the study. Eighty-two ulcers were treated in the referral clinic and 75 ulcers were treated in the general ophthalmology clinic. MAIN OUTCOME MEASURES: The authors determined the percentage of corneal ulcers in each clinical setting that failed to respond to empiric therapy and required a culture directed change in treatment. RESULTS: One hundred fifty-seven ulcers were included. Eight (10%) of the 82 patients treated in the Cornea Clinic had treatment altered based on culture and sensitivity results. All 75 patients in the general clinic responded to empiric antibiotics, such that culture data never were required for modification of therapy (0%, P = 0.007). In contrast to patients treated in the Cornea Clinic, patients treated in the general clinic had smaller, more peripheral ulcers, shorter duration of symptoms, and fewer risk factors for corneal ulceration other than contact lens wear. CONCLUSIONS: Cornea specialists, who are referred the most severe cases, should consider culturing most corneal ulcers. However, it appears reasonable for general ophthalmologists to use culturing more judiciously. Patients with significant corneal ulcers should be cultured regardless of the clinic to which they present. However, small, peripheral ulcers respond extremely well to current, broad-spectrum antibiotics. Close follow-up is mandatory to discover the rare patient who will not respond to empiric therapy. PMID- 9373124 TI - Ofloxacin monotherapy for the primary treatment of microbial keratitis: a double masked, randomized, controlled trial with conventional dual therapy. The Ofloxacin Study Group. AB - BACKGROUND: Ofloxacin is a potent broad-spectrum fluoroquinolone antibiotic commercially available as a topical ophthalmic preparation. The authors compared ofloxacin (0.3%) as a single therapy with their conventional dual therapy of specially prepared, fortified gentamicin (1.5%) and cefuroxime (5.0%) drops for the treatment of suspected microbial keratitis. METHODS: The authors enrolled 122 patients with a clinical diagnosis of microbial keratitis in a prospective, randomized, controlled, double-masked study to compare the two therapies. The ofloxacin drops were decanted into identical-looking bottles to the conventional treatment and dispensed with a second bottle containing saline only. The initial and subsequent assessments noted any risk factors, the size and location of the ulcer, and any evidence of corneal and conjunctival toxicity. All ulcers were scraped for microbiologic culture, and isolated organisms were tested for sensitivity to the trial antibiotics. For statistical analysis, a "cure" was defined as complete healing of the ulcer (no epithelial defect). A ratio of the two outcome proportions and its confidence limits was used to compare the two treatment groups. Multiple regression analysis using Poisson models was used to adjust for confounding factors that may have modified the outcome ratios. RESULTS: There was no difference in the treatment success between the two treatments, with 67.9% of the conventional treatment group and 62.1% of the ofloxacin group being cured within 14 days (ratio, 1.09; [95% confidence interval, 0.83-1.43]; P = 0.59). However, there was significantly more toxicity encountered with the conventional treatment group (50.8% vs. 10.2%; ratio, 5.00 [95% confidence interval, 2.25-11.11]; P < 0.0001). Poisson regression with adjustment for confounders did not materially change the ratio proportions for either treatment success or toxicity. There was at least a 90% chance to detect a 30% difference between the groups. CONCLUSIONS: The authors found that the treatment outcomes with ofloxacin monotherapy compared favorably with their conventional therapy and were associated with less toxicity. PMID- 9373125 TI - A multicenter comparison study of the Humphrey Field Analyzer I and the Humphrey Field Analyzer II. AB - PURPOSE: The purpose of the study is to determine the comparability of the 30-2 full-threshold program in the original Humphrey Field Analyzer (HFA) I to the same test procedure in the new Humphrey Field Analyzer II. METHODS: At each of five clinical centers, one eye of patients with ocular hypertension and normal visual fields, patients with early glaucomatous visual field loss, and patients with more advanced visual field loss were tested with the two instruments plus a retest on a separate HFA I. All participants had undergone at least one prior visual field examination. To minimize the influence of any residual learning or fatigue effects, the order of testing for the three visual field examinations was counterbalanced across subjects. A total of 250 patients were tested (81 patients with ocular hypertension, 81 patients with early glaucomatous visual field loss, and 88 patients with more advanced glaucomatous visual field loss). RESULTS: No statistically significant differences were observed between thresholds, visual field indices, or reliability indices obtained with the HFA I and the HFA II. The small differences between the two instruments were equivalent to the variation observed for test-retest measures using only the HFA I. These results were consistent across the range of visual field characteristics shown by the ocular hypertensive, early glaucoma, and moderate glaucoma patient groups. CONCLUSIONS: The authors' results indicate that there are no differences in the visual field results obtained with the HFA I and the HFA II. These findings suggest that with careful attention to test protocols, the HFA I and HFA II may be used interchangeably to observe patients, even within the context of multicenter clinical trials. PMID- 9373126 TI - Automated perimetry in detecting threats to fixation. AB - PURPOSE: To study in glaucoma patients the threat to fixation on a Humphrey field analyzer program 10-2 when one of the four innermost paracentral points is defective on program 30-2. METHODS: Forty-five eyes of 45 patients with chronic open-angle glaucoma in whom at least one of the innermost four defective paracentral points was reproducibly defective on program 30-2 of the Humphrey perimeter, with a size 3 target, on two consecutive tests, were studied with program 10-2. RESULTS: Of the 45 eyes with an abnormal paracentral point of program 30-2, 30 (66%) also showed involvement of a paracentral point on program 10-2, which was considered a threat to fixation. The remaining 15 were considered not to threaten fixation imminently. CONCLUSIONS: In about one third of glaucomatous fields considered to threaten fixation on the standard programs 30-2 and 24-2, the threat was not imminent. The extra evaluation is therefore useful before making radical and precipitous changes in management of the disease. PMID- 9373127 TI - Chronic use of apraclonidine decreases its moderation of post-laser intraocular pressure spikes. AB - OBJECTIVE: The purpose of the study is to investigate the efficacy of 1.0% apraclonidine in preventing intraocular pressure (IOP) spike after argon laser trabeculoplasty (ALT) in patients on chronic apraclonidine therapy compared with patients not on chronic apraclonidine use. DESIGN: The study design was a prospective study. PARTICIPANTS: This study consisted of 231 consecutive eyes of patients with primary open-angle glaucoma undergoing ALT: 70 eyes (30%) were started on a regimen including chronic apraclonidine 0.5% use (group A) and 161 eyes (70%) were started on a regimen without chronic apraclonidine 0.5% use (group B). INTERVENTION: Both groups received one drop of apraclonidine 1.0% 15 minutes before ALT to 180 degrees of previously untreated trabecular meshwork. Intraocular pressure was measured before the procedure and at 5 minutes, 1 hour, and 24 hours after the laser treatment. MAIN OUTCOME MEASURES: Incidences of an IOP spike and mean IOPs at 5 minutes, 1 hour, and 24 hours after the laser treatment were compared between the two groups. Multivariate logistic regression analysis also was carried out to identify the significant risk factors for post ALT IOP spikes despite prophylactic apraclonidine 1.0% treatment. RESULTS: The incidences of IOP spikes greater than 0 mmHg, greater than 2 mmHg, and greater than 5 mmHg at 1 hour after ALT were 32.9%, 22.9%, and 12.9%, respectively, in group A versus 13.7%, 11%, and 3.1%, respectively, in group B (P = 0.0007, P = 0.009, and P = 0.004). Chronic apraclonidine 0.5% use was found to be the only significant risk factor for IOP spikes at 1 hour after ALT by multivariate logistic regression analysis. CONCLUSIONS: The incidences of IOP spikes in group A were significantly greater than in group B and approached the reported incidences of IOP spikes without perilaser apraclonidine prophylaxis. This indicates that peri-ALT apraclonidine is relatively ineffective in patients with chronic apraclonidine 0.5% use (group A) compared with patients without chronic apraclonidine use (group B), presumably because of saturation of the ocular alpha 2 receptors with apraclonidine in patients with chronic apraclonidine use. Therefore, in patients receiving chronic apraclonidine therapy, it is especially important to monitor their post-ALT IOPs and to be prepared to treat postlaser IOP spikes using agents other than apraclonidine. PMID- 9373128 TI - The associations of optic disc hemorrhage with retinal nerve fiber layer defect and peripapillary atrophy in normal-tension glaucoma. AB - OBJECTIVE: The purpose of the study is to elucidate a topographic correlation between optic disc hemorrhages and retinal nerve fiber layer defects as well as peripapillary atrophy in normal-tension glaucoma (NTG). DESIGN: The authors prospectively studied the relation between the precise locations of disc hemorrhages and retinal nerve fiber layer defects in the first part of the study. The authors also compared morphometrically the peripapillary atrophy and the optic disc in eyes with disc hemorrhage with eyes without a history of disc hemorrhage in age-matched patients in the second part of the study. PARTICIPANTS: In part 1, 42 patients with NTG (male/female = 11/31; age, 56.8 +/- 14.2 years) in whom new disc hemorrhages developed were enrolled. In part 2, 51 randomly selected age-matched patients with NTG without a history of disc hemorrhage (male/female = 16/35; age, 55.7 +/- 12.5) were examined. MAIN OUTCOME MEASURE: In part 1, retinal nerve fiber layer defects were observed by scanning laser ophthalmoscopy using an argon-blue laser. In part 2, the area, angular extent, and radial extent of zone beta of peripapillary atrophy and the structural parameters of optic disc were measured by scanning laser tomography using a diode laser. RESULTS: In part 1, the authors detected 64 disc hemorrhages in 48 eyes of 42 patients; retinal nerve fiber layer defects were shown in 47 (97.9%) of 48 eyes by scanning laser ophthalmoscopy. Of 64 disc hemorrhages, 51 (79.7%) coincided with retinal nerve fiber layer defects in location. These 51 hemorrhages were present on the border (41.2%) or adjacent to the border (58.8%) between the retinal nerve fiber layer defect and the apparently healthy-looking retinal nerve fiber layer. In part 2, the prevalence, area, angular extent of zone beta, and ratio of zone beta area to disc area were significantly greater in the disc hemorrhage group than in the nonhemorrhage group, even though there were no significant differences in disc parameters between the two groups. CONCLUSIONS: Disc hemorrhage is associated closely with retinal nerve fiber layer defect in location and the size of peripapillary atrophy in NTG. PMID- 9373129 TI - Optic disc shape, corneal astigmatism, and amblyopia. AB - OBJECTIVE: The cornea and the optic disc form the anteroposterior opening of the sclera. This study evaluated whether an abnormal shape of the optic disc is associated with an abnormal configuration of the cornea measured as corneal astigmatism. DESIGN: The study design was a cross-sectional one. PARTICIPANTS: The study included 882 subjects (430 women, 452 men) with a mean age of 45.9 +/- 13.6 years (mean +/- standard deviation; range, 8-87 years) and a mean refractive error of -1.09 +/- 2.76 diopters (range, -21.0 diopters to +7.0 diopters). INTERVENTION: Corneal astigmatism was determined by keratometry, and the optic disc was analyzed morphometrically by planimetric evaluation of optic disc photographs. MAIN OUTCOME MEASURES: Corneal astigmatism, ratio of minimal-to maximal disc diameter, and optic disc form factor were measured. RESULTS: The amount of corneal astigmatism was significantly (P < 0.001) correlated with an increasingly elongated optic disc shape. Corneal astigmatism was significantly (P < 0.01) higher in eyes with tilted discs. It was significantly (P = 0.006) smaller in eyes with an almost circular disc shape. Amblyopia was significantly (P < 0.05) associated with an elongated optic disc shape and high corneal astigmatism. The axis of corneal astigmatism was correlated with the orientation of the longest disc diameter. The optic disc was significantly (P < 0.05; chi square test) more often horizontally oval in eyes with a steeper horizontal corneal meridian than in eyes with a steeper vertical corneal meridian. Correspondingly, the disc was significantly (P < 0.05) more often vertically oval in eyes with a steeper vertical corneal meridian than in eyes with a steeper horizontal corneal meridian. CONCLUSIONS: An abnormal optic disc shape is significantly correlated with corneal astigmatism. Especially in young children, if an abnormal optic disc shape is found on routine ophthalmoscopy, refractometry should be performed to rule out corneal astigmatism and to prevent amblyopia. The direction of the longest optic disc diameter can indicate the axis of corneal astigmatism. PMID- 9373130 TI - Hyperopia correction by noncontact holmium:YAG laser thermal keratoplasty: U.S. phase IIA clinical study with 2-year follow-up. AB - PURPOSE: This study was performed to determine the long-term efficacy, safety, and stability of noncontact holmium:yttrium aluminum garnet (Ho:YAG) laser thermal keratoplasty (LTK) for correction of low-to-moderate hyperopia. METHODS: The authors treated 1 eye each of 28 patients for correction of low-to-moderate hyperopia (up to +3.88 diopters [D] refractive error) using the Sun 1000 Corneal Shaping System (Sunrise Technologies, Inc., Fremont, CA). Treatments were performed with one or two rings of eight spots per ring with centerline diameters of 6 mm (one ring) or 6 and 7 mm (two rings), ten pulses of laser light at 5-Hz pulse repetition frequency, and pulse energies ranging from 208 to 242 mJ. Follow up was 2 years. RESULTS: At 2 years after surgery, uncorrected distance visual acuity was improved by 1 or more lines of Snellen visual acuity in 19 (73%) of 26 of the treated eyes. The mean lines gained was 2.5 +/- 2.2/3.3 +/- 2.7 for one- and two-ring treatment groups, respectively. The mean change in spherical equivalent of the subjective manifest refraction was -0.53 +/- 0.33 D/-1.48 +/- 0.58 D for one- and two-ring treatment groups. Regression between 1 and 2 years was 0.01 D and 0.16 D, respectively. In the one-ring treatment group (18 eyes), 13 eyes (72%) had refractive corrections (range, -0.38 to -1.13 D), and 5 eyes (29%) were unchanged (within +0.25 D) relative to their preoperative measurements. In the two-ring treatment group, all eight eyes (100%) had reductions in their hyperopia (range of corrections, -0.38 to -2.25 D). None of the eyes lost two or more lines of spectacle-corrected distance visual acuity. There were no sight-threatening complications. CONCLUSIONS: This initial U.S. clinical study indicates that noncontact laser thermal keratoplasty treatment of low hyperopia is safe and produces modest but persistent corrections with 2-year follow-up. Expanded studies of this treatment method are warranted. PMID- 9373131 TI - For how long can regression continue after photorefractive keratectomy for myopia? AB - PURPOSE: The presence and degree of regression were assessed from 18 to 30 months after photorefractive keratectomy (PRK). METHODS: A total of 449 eyes (449 patients) were treated with an Aesculap Meditec 193-nm Arf Excimer laser. These 449 eyes were followed during the first 24 months after PRK, and 252 of these eyes were followed for 24 to 30 months. RESULTS: Thirty (6.7%) of the 449 eyes followed for up to 24 months showed good refractive results during the first year and a half but regressed thereafter and required retreatment. Late regression was confined to subjects with pretreatment myopia above -4.0 diopters (D) and was the same in low- and high-myopic eyes between 18 and 24 months post-PRK. However, between 24 and 30 months, regression was higher in low-myopic eyes, where it reached -0.55 D, than in high-myopic eyes, where it was -0.21 D. This lower frequency of regression in high-myopic eyes is attributed to the relatively high rate of retreatment in this group during the first 18 months after PRK. CONCLUSIONS: Although the findings indicate a fairly low rate of regression after 24 months, there still are insufficient data on which to predict when regression post-PRK stabilizes. PMID- 9373132 TI - Photorefractive keratectomy for hyperopia: six months results in 45 eyes. AB - OBJECTIVE: To evaluate the safety and efficacy of photorefractive and photoastigmatic keratectomy for hyperopia. METHODS: The Chiron Keracor 116 excimer laser (Chiron Technolas, Munich, Germany) was used to create a peripheral annular ablation profile for the correction of hyperopia and a prior cylindrical ablation in the negative axis for correction of the astigmatic component in 45 consecutive eyes with up to +6.50 diopters (D). All patients were followed for a minimum of 6 months. RESULTS: At 6 months, mean subjective refraction was +0.12 D (standard deviation, 0.70), with 87% within 1 D of emmetropia. Ninety-three percent achieved uncorrected visual acuity of 20/40 or better. Three eyes (6.7%) lost 2 lines of best spectacle-corrected visual acuity and six eyes (13.3%) gained 2 lines or more. CONCLUSIONS: Photorefractive and photoastigmatic keratectomy effectively and predictably reduced hyperopia, improving uncorrected visual acuity in all patients at 6 months. Longer follow-up is required to be certain that refractive changes are stable. PMID- 9373133 TI - Excimer laser photorefractive keratectomy for the correction of hyperopia using an erodible mask and axicon system. AB - PURPOSE: The purpose of the study is to evaluate photorefractive keratectomy for the correction of hyperopia using the erodible mask and Axicon system. METHODS: Forty-three patients (43 eyes) with a mean refraction (spherical equivalent) of +4.54 diopter (D) (range, +1.75 to +7.50 D) were treated using a Summit Technology "Apex Plus" excimer laser. This system uses an erodible mask to create a 6.50-mm diameter hyperopic correction over the axial cornea. An Axicon then is used to fashion a 1.50-mm "blend zone" around the correction. On the basis of preoperative refractions, patients were assigned to 3 groups: 2 groups of 14 patients underwent either "+2.00 D" or "+3.00 D" corrections and 15 patients had "+4.00 D" corrections. RESULTS: All patients had a reduction in their hyperopia with an overcorrection, especially in the first month after surgery and some stability in the refractive change at 3 to 6 months. The mean manifest refraction (n = 43) at 6 months was -0.17 D (range, +4.50 D to -3.125 D). Patient satisfaction was high. At 6 months, all eyes had an improvement in unaided near visual acuity. Unaided distance acuity was improved in 37 eyes (86%). A ring of haze 6.5 mm in diameter appeared in all eyes 1 month after surgery. Night halo measurements at 6 months showed no differences from preoperative levels. Flicker contrast sensitivity and forward light scatter (glare) measurements showed no differences after surgery. CONCLUSIONS: In this short-term study, photorefractive keratectomy for hyperopia using the erodible mask and Axicon system appeared to be a promising procedure. Visual performance, in terms of flicker contrast sensitivity, forward light scatter, and night halos, was not compromised. There was an overcorrection based on the manufacturer's algorithms. Manipulation of the treatment algorithms should improve future predictability. PMID- 9373134 TI - The cytosolic glycoprotein FP21 of Dictyostelium discoideum is encoded by two genes resulting in a polymorphism at a single amino acid position. AB - FP21 is a glycoprotein within the cytosolic compartment of Dictyostelium which carries an unusual carbohydrate modification(s) including the sugars fucose, galactose and N-acetylglucosamine. The soluble pool of FP21 from crude extracts resolves chromatographically into two fractions that differ in their glycosylation. Previous gene-mapping studies indicating the existence of two loci suggested that the FP21 fractions might be encoded by different genes. To address this issue, the two genes were cloned and sequenced, leading to the prediction that the protein products would differ by only a single amino acid, Ser or Ala, at codon 39. Protein sequence data on CNBr fragments of purified FP21 showed that both gene products are found in both fractions of the soluble pool. After further purification, the two fractions were no longer chromatographically resolvable, and there was no evidence for charge heterogeneity as determined by 2-D gel electrophoresis of whole cells. Thus, the initial separation of the different soluble subpopulations of this protein appears to be due to distinct molecular complexes, possibly related to differential glycosylation, and is not the result of the genetically-encoded amino acid polymorphism. PMID- 9373135 TI - Genes encoding multiple drug resistance-like proteins in Aspergillus fumigatus and Aspergillus flavus. AB - Polymerase chain reaction using degenerate primers was used to identify genes encoding proteins of the ATP-binding cassette superfamily in Aspergillus fumigatus and Aspergillus flavus. In A. fumigatus, two genes (AfuMDR1 and AfuMDR2) encoding proteins of the ATP-binding cassette superfamily were identified. One gene (AflMDR1) was isolated from A. flavus and is the apparent homologue to AfuMDR1. AfuMDR1 and AflMDR1 encode proteins of molecular weights 148,000 and 143,000, respectively, each containing 12 putative transmembrane regions and two ATP-binding sites. These proteins are arranged in two homologous halves, each half consisting of a hydrophobic region (encoding six putative transmembrane domains) and an ATP-binding site. The AfuMDR1 and AflMDR1-encoded proteins bear a high degree of similarity to the Schizosaccharomyces pombe leptomycin B resistance protein and to human MDR1. The second gene identified in A. fumigatus, AfuMDR2, encodes a protein of molecular weight 85,000, containing four putative transmembrane domains and an ATP binding domain. The encoded protein is similar to those encoded by MDL1 and MDL2, two MDR-like genes of Saccharomyces cerevisiae. Expression of AFUMDR1 in S. cerevisiae conferred increased resistance to the antifungal agent cilofungin (LY121019), an echinocandin B analog. PMID- 9373136 TI - Anf: a novel class of vertebrate homeobox genes expressed at the anterior end of the main embryonic axis. AB - Five novel genes homologous to the homeobox-containing genes Xanf-1 and Xanf-2 of Xenopus and Hesx-1/Rpx of mouse have been identified as a result of a PCR survey of cDNA in sturgeon, zebrafish, newt, chicken and human. Comparative analysis of the homeodomain primary structure of these genes revealed that they belong to a novel class of homeobox genes, which we name Anf. All genes of this class investigated so far have similar patterns of expression during early embryogenesis, characterized by maximal transcript levels being present at the anterior extremity of the main embryonic body axis. The data obtained also suggest that, despite considerable high structural divergence between their homeodomains, all known Anf genes may be orthologues, and thus represent one of the most quickly evolving classes of vertebrate homeobox genes. PMID- 9373137 TI - Identification and sequence of human PKY, a putative kinase with increased expression in multidrug-resistant cells, with homology to yeast protein kinase Yak1. AB - We have previously shown that several protein kinases are present in higher activity levels in multidrug resistant cell lines, such as KB-V1. We have now isolated a gene that codes for a putative protein kinase, PKY, of over 130 kDa that is expressed at higher levels in multidrug-resistant cells. RNA from KB-V1 multidrug-resistant cells was reverse-transcribed and amplified by using primers derived from consensus regions of serine threonine kinases and amplified fragments were used to recover overlapping clones from a KB-V1 cDNA library. An open reading frame of 3648 bp of DNA sequence predicting 1215 aa, has been identified. This cDNA hybridizes to a mRNA of about 7 kb which is expressed at high levels in human heart and muscle tissue and overexpressed in drug-resistant KB-V1 and HL60/ADR cells. Because its closest homolog is the yeast serine/threonine kinase, Yak1, we have called this gene PKY. PKY is also related to the protein kinase family that includes Cdks, Gsk-3, and MAPK proline-directed protein kinases. This protein represents the first of its type known in mammals and may be involved in growth control pathways similar to those described for Yak1, as well as possibly playing a role in multidrug resistance. PMID- 9373138 TI - Gene within gene configuration and expression of the Drosophila melanogaster genes lethal(2) neighbour of tid [l(2)not] and lethal(2) relative of tid[l(2)rot]. AB - In this paper, we describe the structure and temporal expression pattern of the Drosophila melanogaster genes l(2)not and l(2)rot located at locus 59F5 vis a vis the tumor suppressor gene l(2)tid described previously and exhibiting a gene within gene configuration. The l(2)not protein coding region, 1530 nt, is divided into two exons by an intron, 2645 nt, harboring the genes l(2)rot, co-transcribed from the same DNA strand, and l(2)tid, co-transcribed from the opposite DNA strand, located vis a vis. To determine proteins encoded by the genes described in this study polyclonal rabbit antibodies (Ab), anti-Not and anti-Rot, were generated. Immunostaining of developmental Western blots with the anti-Not Ab resulted in the identification of a 45-kDa protein, Not45, which is smaller than the Not56 protein predicted from the sequence. Its localization in endoplasmic reticulum (ER) was established by immunoelectron microscopy of Drosophila melanogaster Schneider 2 cells. Not45 shows significant homology to yeast ALG3 protein acting as a dolichol mannosyltransferase in the asparagine-linked glycosylation. It is synthesized ubiquitously throughout embryonic life. The protein predicted from the l(2)rot sequence, Rot57, shows a homology to the NS2B protein of the yellow fever virus1 (yefv1). The results of l(2)rot RNA analysis by developmental Northern blot and by in situ RNA localization, as well as the results of the protein analysis via Western blot and immunohistochemistry suggest that l(2)rot is transcribed but not translated. Since RNAs encoded by the genes l(2)tid and l(2)rot are complementary and l(2)rot is presumably not translated we performed preliminary experiments on the function of the l(2)rot RNA as a natural antisense RNA (asRNA) regulator of l(2)tid expression, expressed in the same temporal and spatial manner as the l(2)tid- and l(2)not RNA. l(2)tid knock-out by antisense RNA yielded late embryonic lethality resulting from multiple morphogenetic defects. PMID- 9373139 TI - The genetics and molecular structure of the Drosophila pair-rule gene odd Oz (odz). AB - Null alleles of the odz pair-rule gene have been generated as small Deficiency chromosome mutations. The true null phenotype of odz in segmentation is now seen to be very similar to that originally characterized, with each odd segment removed. No other previously isolated mutations in the genomic region proved allelic to odz. The generated Deficiencies covering the odz locus and immediately surrounding regions do not cover any other gene tested from that region. The entire odz gene has been cloned and mapped, and represents more than 120 kb of genomic DNA. The gene has been sequenced, except for two very large introns. Analysis of the upstream control region of the gene indicates the presence of a large number of putative binding sites for transcription factors that direct relevant developmentally regulated gene transcription. PMID- 9373140 TI - Complex protein binding to the mouse M-lysozyme gene downstream enhancer involves single-stranded DNA binding. AB - The mouse M-lysozyme downstream enhancer has been previously characterized on several levels of gene regulation. The enhancer was co-localized with a DNase I hypersensitive site in the chromatin of mature macrophages, the in vivo interaction of transcription factor GABP with the enhancer core (MLDE) demonstrated binding being restricted to mature macrophage cells, and analysis of the MLDE methylation state revealed a correlation between demethylation of CpG dinucleotides and the in vivo GABP binding. Here, we analyzed in detail the full length enhancer in addition to the core element. We identified a total of nine binding sites for nuclear factors. Most of these factors are found ubiquitously in all cell types tested. These factors include several unknown proteins as well as the transcription factor NF-Y. In addition, three binding sites for a new single-stranded DNA binding protein were found. The presence of this factor in mature macrophages correlates with the in vivo DNA melting of one of the binding sites and with the enhancer strength. PMID- 9373141 TI - Identification and characterization of the gene for Drosophila S20 ribosomal protein. AB - A cDNA clone that encodes a Drosophila homologue of ribosomal protein S20 was isolated from a Drosophila ovary cDNA library. The Drosophila S20 gene (RpS20) is highly conserved with S20 genes in other organisms. It is a single copy gene and maps to position 92F-93A on polytene chromosomes. No Minute mutation in this location has been reported; at least five essential genes are possible candidates to encode RpS20. RpS20 message is expressed ubiquitously in embryos, but is expressed at high levels in the midgut. PMID- 9373142 TI - Partial nucleotide sequence and organisation of extrachromosomal plastid-like DNA in Plasmodium berghei. AB - The murine malaria parasite Plasmodium berghei contains a plastid-like extrachromosomal genome. This genome is 30.7 kb in size and is transcriptionally active as shown by RT-PCR. DNA sequence analysis of the genome reveals 69.9-95.5% homology to sequences of the 35-kb extrachromosomal circle found in the human malaria species Plasmodium falciparum. Homologous sequences include regions of genes for the ssu-rRNA, lsu-rRNA, rpo B and clusters of t-RNAs. Sequence variation between the two Plasmodium species exists in the non-coding interspacing regions. A physical map has been constructed for the P. berghei circle, indicating the EcoRI and HindIII restriction sites as well as the arrangement of the rRNA, rpo B and tRNA genes. Arrangement of these genes is similar to that found on the P. falciparum 35-kb circle. The P. berghei circular element is distinct from the mitochondrial 6-kb DNA of both the murine and the human Plasmodium species. Preliminary results indicate that the circle may be a useful target for drug therapy. PMID- 9373143 TI - Molecular characterization of a Dictyostelium G-protein alpha-subunit required for development. AB - Dictyostelium discoideum utilizes G-protein-regulated transmembrane signaling systems to implement its developmental program. This report describes the Dictyostelium G-protein alpha-subunit, G alpha3, and demonstrates that it is required for normal development. G alpha3 is the largest of the four completely sequenced Dictyostelium G-protein alpha-subunits. The difference in size is due to variability in the N-terminal regions. The regions which are affected by the increased size of G alpha3 are the Gbeta gamma binding region and the helical domain that protects the guanine nucleotide cleft. g alpha3- mutants created by gene disruption fail to aggregate. However, when treated with exogenous pulses of cAMP that mimic the endogenous cAMP oscillations, they are able to aggregate, but development arrests at the tipped mound stage. This conditional developmental phenotype suggests that G alpha3 is required for production of the cAMP signal. PMID- 9373144 TI - A binary-BAC system for plant transformation with high-molecular-weight DNA. AB - A binary-BAC (BIBAC) vector suitable for Agrobacterium-mediated plant transformation with high-molecular-weight DNA was constructed. A BIBAC vector is based on the bacterial artificial chromosome (BAC) library vector and is also a binary vector for Agrobacterium-mediated plant transformation. The BIBAC vector has the minimal origin region of the Escherichia coli F plasmid and the minimal origin of replication of the Agrobacterium rhizogenes Ri plasmid, and thus replicates as a single-copy plasmid in both E. coli and in A. tumefaciens. The T DNA of the BIBAC vector can be transferred into the plant nuclear genome. As examples, a 30-kb yeast genomic DNA fragment and a 150-kb human genomic DNA fragment were inserted into the BIBAC vector; these constructs were maintained in both E. coli and A. tumefaciens. In order to increase the efficiency of transfer of unusually large BIBAC T-DNAs, helper plasmids that carry additional copies of A. tumefaciens virulence genes virG and virE were constructed. These helper plasmids are compatible with, and can be present in addition to, the BIBAC vector in the A. tumefaciens host. This report details the components of the BIBAC system, providing information essential to the general understanding and the application of this new technology. PMID- 9373146 TI - Transcriptional analysis of mga, a regulatory gene in Streptococcus pyogenes: identification of monocistronic and bicistronic transcripts that phase vary. AB - Transcription of several surface virulence proteins of Streptococcus pyogenes is regulated by Mga, a protein that shows homology to response regulators of two component signal-transducing systems. Two of these surface virulence proteins, M protein and C5a peptidase, undergo phase variation. To determine whether Mga itself undergoes phase variation and might allow the phasing switch to coordinate the activity of these genes, expression of the mga gene was analyzed. We show for the first time that there are two mga-specific transcripts: a 3.8-kb bicistronic message that includes both mga and emm12 genes and a monocistronic 1.6-kb mga message. Both transcripts phase vary and are present in higher amounts in M+ variants than in M- variants. Incubation of RNA with rifampicin indicates that the smaller 1.6-kb message is not a processed product. Two promoters were mapped upstream of mga: P1 at position 666 (-395) and P2 at position 978 (-83). In strain CS46 (delta mga), transcription initiation from the P1 promoter does not occur, and multiple start sites are found around the P2 promoter. Complementation experiments indicate that sequences upstream of the P2 promoter are required for activation of emm12 and scpA by Mga in trans. PMID- 9373147 TI - Using Schizosaccharomyces pombe as a host for expression and purification of eukaryotic proteins. AB - We have established a eukaryotic protein expression and purification system by using the yeast Schizosaccharomyces pombe as the host and the glutathione S transferase (GST) as a protein purification tag. This system provides opportunities for rapid, inexpensive, and high yield production of proteins in a eukaryotic organism. Unlike E. coli, S. pombe provides for post-translational modifications of the proteins, which are often critical for the structure and function of eukaryotic proteins. Two vectors have been constructed for protein expression in S. pombe, pESP-1 and pESP-2. Both vectors use the nmt1 promoter for constitutive or induced expression of the gene of interest. Expressed GST-tagged proteins are easily and rapidly purified using glutathione agarose beads. The GST tag can be removed from the fusion proteins by treatment with either the thrombin or enterokinase protease. Proteins expressed from the pESP-2 vector will yield native amino acid sequence when the GST tag is removed by treatment with enterokinase. Nine proteins have been purified by using the system with yields ranging from 1.0 mg/l to 12.5 mg/l of induced culture. PMID- 9373145 TI - Cloning and characterization of BS-cadherin, a novel cadherin from the colonial urochordate Botryllus schlosseri. AB - The genomic DNA for a novel member of the cadherin family (BS-cadherin) was cloned and characterized from the colonial marine invertebrate, Botryllus schlosseri. Using a differential display of mRNA by means of PCR, a small cDNA fragment of 380 nucleotides was found to be specifically expressed in a colony undergoing allogeneic rejection processes, as compared with naive parts of the same genotype. This cDNA fragment was used as a probe to screen a genomic library of Botryllus schlosseri. A genomic fragment containing an ORF of 2718 nucleotides, with no introns, was isolated. The encoded protein exhibits a typical structure of cadherins; an extracellular domain with conserved repeated sequences (cadherin signatures), a single transmembrane domain and a conserved cytoplasmic tail region. The BS-cadherin amino-acid sequence shows 32-35% identity to mature classical cadherins type I, e.g., N-, P- and E-cadherin as well as mature classical cadherins type II, e.g., human cadherin-6, -8 and OB cadherin. This cadherin represents a new cadherin gene family, evolutionarily distant to all other known classical cadherins. PMID- 9373148 TI - Identification of an achaete-scute homolog, Fash1, from Fugu rubripes. AB - Proteins of the achaete-scute family of transcription factors play important roles in neurogenesis in both invertebrates and vertebrates. Here, we report the cloning and characterization of a Japanese pufferfish, Fugu rubripes achaete scute homolog 1, Fash1. Sequence alignment of the predicted amino acid sequence of Fash1 with other vertebrate homologs of the achaete scute homolog 1 subclass shows that the carboxyl 2/3 of the protein, including the basic helix-loop-helix, a putative nuclear localization signal and several consensus phosphorylation sites, is highly conserved. Strikingly, the similarity in this region between eight vertebrate species is close to 90%. PMID- 9373150 TI - A novel dicistronic AAV vector using a short IRES segment derived from hepatitis C virus genome. AB - Adeno-associated virus (AAV) vectors have a limited capacity for packaging DNA. To insert both a therapeutic gene and a selectable marker gene in the same AAV vector efficiently, we developed a novel dicistronic AAV vector containing a 230 base pairs (bp) internal ribosome entry site (IRES) element derived from hepatitis C virus (HCV) genome and a 420 bp blasticidin S-resistance gene (bsr) as a small selectable marker in the second cistron. The 650 bp HCV IRES-bsr construct was placed downstream of the 3' end of the luciferase gene (Luc) under the control of the human cytomegalovirus (CMV) promoter. This dicistronic gene conferred blasticidin S-resistance to 293 cells besides luciferase activity, when examined not only by transfection but also by transduction using AAV vectors. The dicistronic AAV vector harbouring HCV IRES-bsr is capable of expressing a therapeutic gene of up to 3.6 kilobases (kb) (including promoter/enhancer elements) as well as a selectable marker gene. If a selectable marker gene is not necessary, this vector is able to incorporate two different kinds of therapeutic genes more easily than that containing EMCV IRES. The dicistronic AAV vector described here is useful for expressing many kinds of cDNA besides a selectable marker. PMID- 9373149 TI - Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library. AB - Using 'oligo-capped' mRNA [Maruyama, K., Sugano, S., 1994. Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides. Gene 138, 171-174], whose cap structure was replaced by a synthetic oligonucleotide, we constructed two types of cDNA library. One is a 'full length-enriched cDNA library' which has a high content of full-length cDNA clones and the other is a '5'-end-enriched cDNA library', which has a high content of cDNA clones with their mRNA start sites. The 5'-end-enriched library was constructed especially for isolating the mRNA start sites of long mRNAs. In order to characterize these libraries, we performed one-pass sequencing of randomly selected cDNA clones from both libraries (84 clones for the full length enriched cDNA library and 159 clones for the 5'-end-enriched cDNA library). The cDNA clones of the polypeptide chain elongation factor 1 alpha were most frequently (nine clones) isolated, and more than 80% of them (eight clones) contained the mRNA start site of the gene. Furthermore, about 80% of the cDNA clones of both libraries whose sequence matched with known genes had the known 5' ends or sequences upstream of the known 5' ends (28 out of 35 for the full length enriched library and 51 out of 62 for the 5'-end-enriched library). The longest full-length clone of the full length-enriched cDNA library was about 3300 bp (among 28 clones). In contrast, seven clones (out of the 51 clones with the mRNA start sites) from the 5'-end-enriched cDNA library came from mRNAs whose length is more than 3500 bp. These cDNA libraries may be useful for generating 5' ESTs with the information of the mRNA start sites that are now scarce in the EST database. PMID- 9373151 TI - Primary structure of an invertebrate dihydrolipoamide dehydrogenase with phylogenetic relationship to vertebrate and bacterial disulfide oxidoreductases. AB - Dihydrolipoamide dehydrogenase (E3) is a flavoprotein component of multi-enzyme complexes catalyzing oxidative decarboxylation of alpha-ketoacids in the Krebs' cycle. We have cloned a 2.4-kb E3 cDNA from an arthropod, Manduca sexta, that codes for 497 amino acids and translates to a 51-kDa protein in vitro. Sequences at and around the dinucleotide binding domains, disulfide active site and the C terminal interface domain involved in substrate binding are highly conserved in Manduca E3. Phylogenetic analysis of protein sequences from the flavoprotein class of disulfide oxidoreductases family of enzymes suggests that in spite of the homologous nature of E3 and glutathione reductase (goR) in sequence and structure, E3 shares a common ancestor with mercuric reductase (merA), whereas goR is more related to trypanothione reductase (tryR) than to other members. All members, except goRs, seemed to be monophyletic. Plant goRs seemed to have arisen differently and are more closely related to tryRs than to bacterial and vertebrate goRs. Earlier speculation on the nature of origin of E3 in Pseudomonas is not supported by phylogenetic data. A possible structural relationship of Manduca E3 to other pyridine-binding proteins, such as the neurotransmitter transporters and channels, is proposed. PMID- 9373152 TI - Conservation of a putative AP1 binding site and complete homology to a fetal brain EST in a region upstream of the core muscle promoter in the human dystrophin gene. AB - A region of 744 basepairs (bp) upstream of the muscular dystrophin promoter (UMDP) was amplified by inverse-polymerase chain reaction (PCR), cloned and sequenced. Analysis of this sequence for the presence of putative transcriptional control elements identified several similarities with known cis-acting sequence motifs including two MyoD and two Ap1 motifs. One of these Ap1 motifs was found to be completely conserved within an otherwise highly variable region among five primate species. Complete homology to a human fetal brain expressed sequence tag (EST) was also observed over 201 bp at the 5' end of the UMDP region. Northern blot analysis using a radiolabelled EST probe identified a 1 kb mRNA expressed in human placenta and at lower levels in the heart. These results raise the possibility that additional transcriptional regulatory elements are located upstream of the core muscle promoter, and provide the first evidence for the existence of a gene that overlaps the human dystrophin gene. PMID- 9373153 TI - Chromosomal localization, gene structure and transcription pattern of the ORFX gene, a homologue of the MHC-linked RING3 gene. AB - We have mapped the human ORFX gene to chromosome 9q34 and determined its complete gene structure. Comparison with RING3, the human MHC-linked homologue on 6p21.3, shows the two gene structures to be highly conserved but with an approximate threefold expansion in the ORFX introns. RING3 and ORFX are found to be ubiquitously expressed in human adult and foetal tissues. Evidence suggests that the two genes may have arisen from an ancient duplication in a common ancestral chromosome. PMID- 9373154 TI - Molecular analysis of gene conversion in spermatids from transgenic mice. AB - Investigations into the mechanisms and properties of gene conversion in mammals are greatly restricted by the inability to recover all the products of a meiosis. Additionally, the study of this process has been hampered by the lack of visible markers to detect gene conversion, especially when the events are rare. In previous work, we developed a transgenic system for detection and quantitation of gene conversion events in the germline of mice (Murti, J.R., Bumbulis, M., Schimenti, J.C., 1992. High frequency germline gene conversion in transgenic mice. Mol. Cell. Biol. 12, 2545-2552) that could be exploited as an assay for recombinogenic chemicals (Murti, J.R, Schimenti, K.J., Schimenti, J.C., 1994. A recombination-based transgenic mouse system for genotoxicity testing. Mutat. Res. 307, 583-595). A specific intrachromosomal gene conversion event between two complementarily defective lacZ genes resulted in the production of beta galactosidase in spermatids, enabling a measurement of conversion frequency. Here, we report that the anticancer drug, cisplatin, increased gene conversion in meiotic stage cells in these transgenic mice. Furthermore, a method was developed for direct molecular analysis of transgene conversion events in single or pooled lacZ-positive spermatids. The ability to identify gametes that have undergone a rare gene conversion event, followed by molecular amplification of the recombinant gene, should make it possible to investigate the mechanisms of genetic recombination in mammals in greater detail than previously possible. PMID- 9373155 TI - Identification of dynein heavy chain genes expressed in human and mouse testis: chromosomal localization of an axonemal dynein gene. AB - Dynein heavy chains are involved in microtubule-dependent transport processes. While cytoplasmic dyneins are involved in chromosome or vesicle movement, axonemal dyneins are essential for motility of cilia and flagella. Here we report the isolation of dynein heavy chain (DHC)-like sequences in man and mouse. Using polymerase chain reaction and reverse-transcribed human and mouse testis RNA cDNA fragments encoding the conserved ATP binding region of dynein heavy chains were amplified. We identified 11 different mouse and eight human dynein-like sequences in testis which show high similarity to known dyneins of different species such as rat, sea urchin or green algae. Sequence similarities suggest that two of the mouse clones and one human clone encode putative cytoplasmic dynein heavy chains, whereas the other sequences show higher similarity to axonemal dyneins. Two of nine axonemal dynein isoforms identified in the mouse testis are more closely related to known outer arm dyneins, while seven clones seem to belong to the inner arm dynein group. Of the isolated human isoforms three clones were classified as outer arm and four clones as inner arm dynein heavy chains. Each of the DHC cDNAs corresponds to an individual gene as determined by Southern blot experiments. The alignment of the deduced protein sequences between human (HDHC) and mouse (MDHC) dynein fragments reveals higher similarity between single human and mouse sequences than between two sequences of the same species. Human and mouse cDNA fragments were used to isolate genomic clones. Two of these clones, gHDHC7 and gMDHC7, are homologous genes encoding axonemal inner arm dyneins. While the human clone is assigned to 3p21, the mouse gene maps to chromosome 14. PMID- 9373156 TI - Cloning and sequencing of complement component C9 and its linkage to DOC-2 in the pufferfish Fugu rubripes. AB - The Japanese pufferfish Fugu rubripes has a 400 Mb genome with high gene density and minimal non-coding complexity, and is therefore an ideal vertebrate model for sequence comparison. The identification of regions of conserved synteny between Fugu and humans would greatly accelerate the mapping and ordering of genes. Fugu C9 was cloned and sequenced as a first step in an attempt to characterize the region in Fugu homologous to human chromosome 5p13. The 11 exons of the Fugu C9 gene share 33% identity with human C9 and span 2.9 kb of genomic DNA. By comparison, human C9 spans 90 kb, representing a 30-fold difference in size. We have also determined by cosmid sequence scanning that DOC-2, a tumour suppresser gene which also maps to human 5p13, lies 6-7 kb from C9 in a head-to-head or 5' to 5' orientation. These results demonstrate that the Fugu C9/DOC-2 locus is a region of conserved synteny. Sequence scanning of overlapping cosmids has identified two other genes, GAS-1 and FBP, both of which map to human chromosome 9q22, and lie adjacent to the Fugu C9/DOC-2 locus, indicating the boundary between two syntenic regions. PMID- 9373157 TI - Membrane association of FtsY, the E. coli SRP receptor. AB - FtsY, the Escherichia coli homologue of the eukaryotic SRP receptor (SR alpha), is located both in the cytoplasm and in the inner membrane of E. coli. Similar to SR alpha, FtsY consists of two major domains: a strongly acidic N-terminal domain (A) and a C-terminal GTP binding domain (NG) of which the crystal structure has recently been determined. The domains were expressed both in vivo and in vitro to examine their subcellular localization. The results suggest that both domains associate with the membrane but that the nature of the association differs. PMID- 9373158 TI - Fostriecin, an antitumor antibiotic with inhibitory activity against serine/threonine protein phosphatases types 1 (PP1) and 2A (PP2A), is highly selective for PP2A. AB - Fostriecin, an antitumor antibiotic produced by Streptomyces pulveraceus, is a strong inhibitor of type 2A (PP2A; IC50 3.2 nM) and a weak inhibitor of type 1 (PP1; IC50 131 microM) serine/threonine protein phosphatases. Fostriecin has no apparent effect on the activity of PP2B, and dose-inhibition studies conducted with whole cell homogenates indicate that fostriecin also inhibits the native forms of PP1 and PP2A. Studies with recombinant PP1/PP2A chimeras indicate that okadaic acid and fostriecin have different binding sites. PMID- 9373159 TI - Evidence for protein dolichylation. AB - Labeling of human colon carcinoma cells with [3H]dol, followed by extensive delipidation and removal of dol-P oligosaccharides, showed that dol are bound to cellular proteins with sizes of 5, 10, 27, 75 and > 140 kDa. HPLC purification of proteolytic products of [3H]dol- and [35S]cys-labeled proteins revealed a hydrophobic peak containing both dol and cysteine. The dol/cys-labeled products were clearly separated from GG-cys, and exhibited a hydrophobicity between that of dol-P and dol. In another set of experiments delipidated proteins were treated with methyl iodide, which cleaves thioether bonds. After HPLC purification of released dol-like lipids, these were subjected to mass spectrometry. This demonstrated molecular ions with the same mass as that of dol. Taken together our data provide evidence for the existence of proteins covalently modified with dol. PMID- 9373160 TI - Translational control of terminal oligopyrimidine mRNAs requires a specific regulator. AB - Terminal oligopyrimidine (TOP) mRNAs are a group of messengers translationally regulated according to the growth status of the cell. Two hypotheses have been proposed for the mechanism of the regulation: (i) there is a specific translational regulator which can reversibly alter TOP-mRNA structure, (ii) a component of the general translational apparatus can specifically affect the translation of TOP-mRNAs. To verify one of the two hypotheses we induced a partial inhibition of translation initiation in Xenopus cultured cells and analyzed the effect on TOP-mRNA translation. Our results suggest that a specific regulator is necessary to explain the translational control of these of mRNAs. PMID- 9373161 TI - NGF exhibits a pro-apoptotic activity for human vascular smooth muscle cells that is inhibited by TGFbeta1. AB - Apoptosis of vascular smooth muscle cells (SMCs) has been described in culture and also during remodelling of the artery following injury. However, the mediators that regulate apoptosis in SMCs are unknown. Because neurotrophins, a family of related polypeptide growth factors, including nerve growth factor (NGF) and its cognate receptor TrkA have been shown to be strongly expressed in atherosclerotic lesions, the present study was undertaken to evaluate in vitro, the activity of NGF with regard to apoptosis of confluent cultures of human aortic SMCs. We report here that NGF induced apoptosis of SMCs in a dose dependent manner. This effect was detected from the concentration of 1 ng/ml and reached a maximum at 100 ng/ml. The concentration that induced a half-maximum effect was 8.8 ng/ml. The pro-apoptotic activity of NGF was time dependent and was significant after 3 h of incubation. The pro-apoptotic activity of NGF was blocked in a dose-dependent manner by K-252a, an inhibitor of TrkA tyrosine phosphorylation, suggesting that a NGF/TrkA signal transduction pathway could activate apoptotic cell death programs in human SMCs. Significantly, NGF-induced apoptosis was inhibited by wortmannin and PD 98059, showing that both PI3 kinase and MEK kinase were involved. At a NGF concentration that strongly induced apoptosis (100 ng/ml), TGFbeta1 which has been identified several times as a protective factor, dose dependently inhibited the pro-apoptotic effect of NGF. The IC50 value was 1.5 ng/ml. These results indicate that, at least in vitro, TGFbeta1 can inhibit the pro-apoptotic activity of NGF for SMCs therefore suggesting that TGFbeta1 has the capacity to diminish the deleterious consequences of an excitotoxic or ischemic injury that might occur during atherogenesis or following angioplasty. PMID- 9373162 TI - Glutamate-286 mutants of cytochrome bo-type ubiquinol oxidase from Escherichia coli: influence of mutations on the binuclear center structure revealed by FT-IR and EPR spectroscopies. AB - Glutamate-286 mutants of cytochrome bo-type ubiquinol oxidase from Escherichia coli were examined by EPR and FT-IR spectroscopies. We confirmed a very low enzymatic activity for E286Q. However, E286D retained one-third of the wild-type activity, probably due to the presence of the carboxylic group on the side-chain. The effect of the mutations at position 286 on the binuclear site was observed clearly in the EPR spectral change for the air-oxidized state. The effect was more significantly manifested in the presence of cyanide or azide in the oxidized state. In contrast, the mutations only slightly perturbed the binuclear center of the CO-reduced enzymes. These results indicate the importance of a direct through bond connectivity between CuB and Glu286 via Pro285 and His284. PMID- 9373163 TI - Dissociation of tubulin assembly-inhibiting and aggregation-promoting activities by a vinblastine derivative. AB - A fluorescent vinblastine analogue, vinblastine-4'-anthranilate (Antvin), that binds to the vinca site on tubulin, inhibits tubulin assembly but does not lead to spiral or other large aggregate formation at concentrations up to 1.6 mM. As judged by turbidity, 90 degrees light scattering and fluorescence anisotropy, little aggregation could be detected. This is in marked contrast to vinblastine and suggests that inhibition of assembly and aggregate formation can be dissociated from each other by suitable substitution in vinblastine. PMID- 9373164 TI - Regulation of ZiRF1 and basal SP1 transcription factor MRE-binding activity by transition metals. AB - The metal-dependent activation of metallothionein (MT) genes requires the interaction of positive trans-activators (MRFs) with metal-regulatory (MRE) regions of MT promoters. In this report, we examined the role of transition metals in modulating the MRE-binding activities of two different MRE-binding proteins: the metal-regulated factor ZiRF1 and the basal factor SP1. We showed the ability of both proteins to interact with a similar sequence specificity with the cognate target site (MRE-S) of another known MRE-binding protein, mMTF1. We next evaluated the role of metal ions in modulating the MRE-binding activity of recombinant ZiRF1 and basal SP1 proteins by measuring the effect of different metal chelators on DNA interaction. We observed a dose-dependent inhibition of the GST-ZiRF1/MRE-binding activity using three different metal chelators: EDTA, 1,10 PHE and TPEN. Interestingly, EDTA treatment failed to inhibit the recombinant SP1 MRE-binding activity while the effect of 1,10 PHE was comparable to that obtained analyzing 1,10 PHE-treated GST-ZiRF1. The MRE-binding complexes detected in cell extracts showed a response to metal chelator treatment very similar to that displayed by the recombinant ZiRF1 and SP1 proteins. The hypothesis of mutual interactions of both basal and metal-regulated transcription factors with the same metal-regulatory regions is discussed. PMID- 9373165 TI - Binding affinities of insulin-like growth factor-I (IGF-I) fusion proteins to IGF binding protein 1 and IGF-I receptor are not correlated with mitogenic activity. AB - In this report, comparisons between molecular affinities and cellular proliferation activities have been made for insulin-like growth factor-I (IGF-I) and two IGF-I fusion proteins in order to evaluate fusion proteins as tools for receptor binding studies. Binding affinities and growth promoting effects of the N-terminal fusion Z-IGF-I and the C-terminal fusion IGF-I-Z, and native recombinant human IGF-I, were analyzed. Binding kinetic properties of the three IGF-I variants were analyzed using BIAcore kinetic interaction analysis testing for binding to both human IGF binding protein 1 (IGFBP-1) and a soluble form of the human IGF type I receptor extracellular domains (sIGF-IR). The growth promoting effects on SaOS-2 human osteosarcoma cells of the different fusion proteins were analyzed. A comparison of receptor binding affinities and growth promoting effects shows that the fusion protein receptor affinity does not correlate with proliferative potential. The IGF-I-Z fusion, with the lowest receptor affinity, shows similar proliferative potential to native IGF-I. However, the Z-IGF-I fusion protein, with twice the receptor affinity of IGF-I-Z, displays only about 70% of the IGF-I-Z growth promoting activity. Both IGF-I fusion proteins possess similar affinity to IGFBP-1. These results indicate that determinants other than the receptor affinity could be involved in the regulation of IGF-I proliferative action. This study demonstrates that ligand fusion proteins may be useful to study mechanisms of ligand induced receptor activation. PMID- 9373166 TI - Trifluoroethanol induces the self-association of specific amphipathic peptides. AB - We have examined the effect of trifluoroethanol (TFE) on the solution behaviour of three amphipathic peptides. One of the peptides, containing three heptad repeat units (Ac-YS-(AKEAAKE)3GAR-NH2), remained monomeric under conditions where TFE induced a two-state transition from a random coil to an alpha-helix. In contrast, the TFE-induced alpha-helical formation of two peptides derived from human apolipoproteins C-II and E was accompanied by the formation of discrete dimers and trimers, respectively. The apolipoprotein C-II peptide further aggregated to form beta-sheet at higher concentrations of TFE (50% v/v). The results suggest a class of peptides capable of discrete self-association in the presence of cosolvents which favour intramolecular hydrogen bonding. PMID- 9373167 TI - Stimulation of prostaglandin G/H synthase-2 expression by arachidonic acid monoxygenase product, 14,15-epoxyeicosatrienoic acid. AB - The relationship between arachidonic acid (AA) mobilization and transcription of immediate-early genes, particularly of prostaglandin G/H synthase-2 (PGHS-2), in intestinal crypt epithelial cells was analyzed. PGHS-2 mRNA and protein synthesis were stimulated by its own substrate, AA; actinomycin D, a transcription inhibitor, prevented the AA-induced increase in PGHS-2 mRNA. Eicosatetraynoic acid, an inhibitor of AA utilization, significantly reduced PGHS-2 mRNA synthesis elicited by AA. Inhibitors of cytochrome P450 monoxygenases, ketoconazole and miconazole, also prevented PGHS-2 mRNA synthesis in a dose-dependent manner. Phenyl chalcone oxide, an epoxide hydrolase inhibitor, potentiated AA-induced PGHS-2 mRNA synthesis. Of the four regioisomers of arachidonic acid epoxides, only 14,15-epoxyeicosatrienoic acid elicited the expression of PGHS-2 in intestinal crypt epithelial cells. This is the first direct evidence of stimulation of an immediate-early gene product, specifically PGHS-2, by an AA epoxygenase metabolite, 14,15-epoxyeicosatrienoic acid, as well as of a heterologous regulation of PGHS-2 synthesis by these monoxygenase products. PMID- 9373168 TI - Effect of glucocorticoids on the synthesis of antimicrobial peptides in amphibian skin. AB - Gene-encoded peptide antibiotics are widespread in insects, plants and vertebrates and confer protection against bacterial and fungal infections. NF kappaB is an important transcription factor for many immunity-related mammalian proteins and also for insect immune genes. The activity of NF-kappaB is regulated by the interaction with an inhibitor, I kappaB. It was recently demonstrated that glucocorticoids induce the synthesis of I kappaB in human cell lines. So far, all genes for peptide antibiotics have promoter motifs with NF-kappaB binding sites, but its actual function in peptide regulation has been studied only in insects. Here we show that glucocorticoid treatment of the frog Rana esculenta inhibits the transcription of all genes encoding antibacterial peptides by inducing the synthesis of I kappaB alpha. These results suggest that also in vertebrates peptide-mediated innate immunity is controlled by NF-kappaB-regulated transcription. PMID- 9373169 TI - Massive glycation of protein HC, a low molecular weight lipocalin, in non diabetic individuals. AB - Human protein HC is a member of the lipocalin superfamily with unique properties since it carries a covalently bound fluorescent chromophore mediating the linkage of the major part of protein HC to several plasma proteins, with IgA as the dominating complex partner. Native protein HC displays characteristic absorption and fluorescence spectra similar to those of glycated proteins with advanced glycosylation end products (AGEs). In vitro glycation of protein HC induces the formation of fibril aggregates with a corresponding increase of absorption in the visible region of the spectrum. Boronate-affinity chromatography and a novel galactosyltransferase assay indicate that protein HC is modified with residues of glucose exposed in a terminal non-reducing position which is typical of glycated proteins. The glycation level of several isolated batches of protein HC as measured by both assays was around 35%, which represents the highest level described for human plasma-derived proteins from healthy individuals. PMID- 9373170 TI - The 20S proteasome gene family in Arabidopsis thaliana. AB - The complexity of the proteasome gene family in higher plants was investigated by identification and sequencing cDNA clones from the Arabidopsis thaliana database showing homologies to 20S proteasome subunits. We identified plant counterparts for each of the 14 proteasomal subunit subfamilies. Moreover, several of them were highly related isoforms. Mapping data indicate a random distribution of the proteasome genes over the Arabidopsis genome. PMID- 9373171 TI - Oxidative DNA base damage and antioxidant enzyme levels in childhood acute lymphoblastic leukemia. AB - We have investigated the levels of several antioxidant enzymes and the level of oxidative DNA base damage in lymphocytes of children with acute lymphoblastic leukemia (ALL) and in disease-free children. Children with ALL had just been diagnosed with the disease and had received no therapy prior to obtaining blood samples. A multitude of typical hydroxyl radical-induced base lesions in lymphocyte DNA of children were identified and quantified by gas chromatography isotope dilution mass spectrometry. Higher levels of DNA base lesions were observed in patients with ALL than in children without the disease. The levels of the antioxidant enzymes glutathione peroxidase, catalase and superoxide dismutase in lymphocytes of ALL patients were lower than in lymphocytes of controls. These findings are in agreement with earlier observations in various types of adulthood cancer. Some of the identified DNA base lesions are known to possess premutagenic properties and may play a role in carcinogenesis. The results may indicate a possible link between decreased activities of antioxidant enzymes and increased levels of DNA base lesions due to oxidative damage, and support the notion that free radical reactions may be increased in malignant cells. PMID- 9373172 TI - Chicken thyroid hormone receptor alpha requires the N-terminal amino acids for exclusive nuclear localization. AB - The subcellular localization of natural and engineered forms of the chicken thyroid hormone receptor (cTR alpha) is dependent on amino acids encoded in the N terminal region. The full length receptor protein, cTR alpha-p46, was found to localize exclusively to the nucleus, whereas the N-terminally shorter variant, cTR alpha-p40, localizes to both the nucleus and the cytoplasm. The exclusive nuclear localization of cTR alpha-p46 is dependent on the presence of the first 11 N-terminal amino acids, but independent of the phosphorylation of the serine at position 12. Our data identify a novel role for an N-terminal domain of the full length thyroid hormone receptor. PMID- 9373173 TI - Suramin enters and accumulates in low pH intracellular compartments of v-sis transformed NIH 3T3 cells. AB - Using acridine orange as a reporter compound, we demonstrate that suramin enters and accumulates in low pH intracellular compartments (endosomes, lysosomes, and trans-Golgi complex) of normal and v-sis-transformed NIH 3T3 cells. The concentration of suramin in these acidic compartments is estimated to be > 150 microM, higher than the concentration known to completely inhibit interaction of the platelet-derived growth factor (PDGF) receptor and v-sis gene product. These results support the hypothesis that suramin reverses the transformed phenotype of v-sis-transformed cells by entering the cell via endocytosis and blocking interaction of the v-sis gene product and PDGF receptor in intracellular organelles. PMID- 9373174 TI - A novel small stable RNA, 6Sa RNA, from the cyanobacterium Synechococcus sp. strain PCC6301. AB - We isolated a novel RNA species from the unicellular cyanobacterium Synechococcus PCC6301 and determined its gene sequence. This novel RNA was termed 6Sa RNA from its length (185 nt). Cross-hybridization of 6Sa RNA to other related microorganisms suggests that its existence is restricted to the Synechococcus genus or related organisms. A high level of accumulation of this RNA was observed by Northern analysis, indicating that 6Sa RNA is stable in cells. Computer-aided prediction of the 6Sa RNA secondary structure also supports its stability. PMID- 9373175 TI - Further evidence that the inhibition of glycogen synthase kinase-3beta by IGF-1 is mediated by PDK1/PKB-induced phosphorylation of Ser-9 and not by dephosphorylation of Tyr-216. AB - 293 cells were transfected with wild-type GSK3beta (WT-GSK3beta) or a mutant in which the PKB phosphorylation site (Ser-9) was altered to Ala (A9-GSK3beta). Upon stimulation with IGF-1 or insulin, WT-GSK3beta was inhibited 75% or 60%, respectively, whereas the activity of the A9-GSK3beta mutant was unaffected. Incubation of WT-GSK3beta with PP2A1 (a Ser/Thr-specific phosphatase) completely reversed the IGF-1- or insulin-induced inhibition. IGF-1 stimulation did not induce any tyrosine dephosphorylation of WT-GSK3beta or A9-GSK3beta. Coexpression of WT-GSK3beta in 293 cells with either PKB alpha (also known as AKT) or PDK1 (the 'upstream' activator of PKB) mimicked the IGF-1- or insulin-induced phosphorylation of Ser-9 and inactivation of GSK3beta. PMID- 9373176 TI - Tissue specific variants of glutamate transporter GLT-1. AB - cDNA cloning of glutamate transporter GLT-1 from mouse brain and liver has revealed that 5'-ends of the messages are different between brain and liver. In addition, one of the GLT-1 cDNAs isolated from liver has been found to possess a 3'-end different from those of the others. Reverse transcription polymerase chain reaction (RT-PCR) amplification using primers specific for altered 5'-ends has confirmed that brain and liver messages possess their own specific 5'-ends. Both of the two 3'-ends have been demonstrated by RT-PCR to be present not only in liver but also in brain, indicating both brain and liver GLT-1 possess two types of 3'-ends. Although functional properties are not changed by the alteration of N termini and C-termini when expressed in Xenopus laevis oocytes, co-expression of two liver type GLT-1 with different C-termini (mGLT-1A and mGLT-1B) has been found to result in the increase in Vmax of transport without changing Km. These results suggest the tissue specific alternative splicing at 5'-ends of GLT-1 messages and the interesting association of spliced variants with different C termini. PMID- 9373177 TI - Positive autoregulation of ras genes expression in fibroblasts. AB - We have studied the effect of ectopic overexpression of a ras gene on the expression of the other two members of the ras gene family. We obtained NIH3T3 cell lines stably transfected with inducible H-ras and N-ras oncogenes. The expression of these genes is driven by a glucocorticoid-responsive promoter and the addition of dexamethasone resulted in a dramatic induction (10-20-fold) of H- or N-ras mRNA, peaking 4 h after hormone addition. The induction of the expression of ras oncogenes resulted in a transformed phenotype. In quiescent NIH3T3 cells transfected with inducible H-ras oncogenes, the induction of H-Ras was followed 12 h later by a 3-fold increase in the mRNA expression of endogenous K-ras and N-ras. Similarly, in NIH3T3 transfected with inducible N-ras oncogene, the induction of N-ras was followed by an increase in the expression of endogenous K- and H-ras genes. Interestingly, the effect was not limited to the mutated N-ras, as a similar result was obtained in cells transfected with N-ras proto-oncogene. The induction of ras genes expression was not linked to cell cycle progression as it was reproduced in cells arrested in S-phase by pretreatment with hydroxyurea. These results suggest the presence of a positive cross-regulation in the expression among the members of the Ras family. This effect could play a role in Ras-mediated carcinogenesis. PMID- 9373178 TI - TNF-alpha induces apoptosis in rat fetal brown adipocytes in primary culture. AB - The effect of TNF-alpha on cell death in rat fetal brown adipocytes maintained in primary culture was determined. TNF-alpha inhibited proliferation and induced apoptosis in these cells. Most of the cells undergoing apoptosis after TNF-alpha treatment did not express PCNA, suggesting an induction of apoptosis by TNF-alpha in non-proliferative cells. IGF-I but not EGF prevented TNF-alpha-induced apoptosis. PMID- 9373179 TI - Characterization of two receptors for TRAIL. AB - Two receptors for TRAIL, designated TRAIL-R2 and TRAIL-R3, have been identified. Both are members of the tumor necrosis factor receptor family. TRAIL-R2 is structurally similar to the death-domain-containing receptor TRAIL-R1 (DR-4), and is capable of inducing apoptosis. In contrast, TRAIL-R3 does not promote cell death. TRAIL-R3 is highly glycosylated and is membrane bound via a putative phosphatidylinositol anchor. The extended structure of TRAIL-R3 is due to the presence of multiple threonine-, alanine-, proline- and glutamine-rich repeats (TAPE repeats). TRAIL-R2 shows a broad tissue distribution, whereas the expression of TRAIL-R3 is restricted to peripheral blood lymphocytes (PBLs) and skeletal muscle. All three TRAIL receptors bind TRAIL with similar affinity, suggesting a complex regulation of TRAIL-mediated signals. PMID- 9373180 TI - Gly166 in the NK1 receptor regulates tachykinin selectivity and receptor conformation. AB - We have studied the pharmacological properties of genetically engineered human NK1 tachykinin receptors in which residues at the extracellular surface of the fourth transmembranal domain were substituted with the corresponding amino acids from the NK2 receptor. We show that substitution of G166C:Y167F in the human NK1 receptor induces high affinity binding of a group of tachykinin ligands, known as 'septides' (i.e. neurokinin A, neurokinin B, [pGlu6,Pro9]-substance P6-11 and substance P-methylester). In contrast, binding of substance P and non-peptide antagonists is unaffected by these mutations. This effect parallels that found on the rat receptor and is therefore species specific. Second, we demonstrate that mutation of Gly166 to Cys alone is both necessary and sufficient to create this pan-reactive tachykinin receptor, whereas replacement of Tyr167 by Phe has no detectable effect on the pharmacological properties of the receptor. Furthermore, analysis of the effect of N-ethylmaleimide and dithiothreitol on binding of radiolabelled substance P documents differences in the mode in which this ligand interacts with wild-type and mutant receptors and supports the existence of a mutational induced change in the conformational status of the NK1 receptor. PMID- 9373181 TI - Mutational analysis of Yap1 protein, an AP-1-like transcriptional activator of Saccharomyces cerevisiae. AB - To define the essential amino acid residues of Yap1 in stress response, we generated yap1 mutations by in vitro mutagenesis, which cause defects in mediating resistance to the stress of H2O2, but not of CdCl2. Sequence analysis of the mutant yap1 genes revealed three point mutations and two truncation mutations near the carboxy-terminus. The truncation mutations resulted in hyperresistance to cadmium. Northern blot analysis of stress-induced levels of TRX2 and GSH1 mRNAs indicated that the ability of the mutant Yap1 protein to induce transcriptional activation of target genes correlates well with its ability to confer stress resistance. The carboxy-terminal domain of Yap1 appears to act negatively in cadmium resistance. PMID- 9373182 TI - Organization and expression of the chum salmon insulin-like growth factor II gene. AB - IGF-II plays an important role in growth and development of vertebrates. In the present study, the characterization of the first fish IGF-II gene, chum salmon IGF-II, is described. The sIGF-II gene consists of four exons, spanning a region of 9 kbp, that encode the 214 aa IGF-II precursor. While the amino acid sequences of fully processed IGF-II of salmon and mammalian species are very similar, the prepro-peptide sequence deviates extensively in the signal- and E-peptide domains. The transcription initiation site of the sIGF-II gene was localized within a 30 nt region employing RT-PCR. Using sIGF-II promoter-luciferase constructs it was demonstrated that the sIGF-II gene has a relatively strong promoter that contains tissue-specific regulatory elements. PMID- 9373183 TI - FNR is a direct oxygen sensor having a biphasic response curve. AB - FNR is a transcription regulator that controls the expression of target genes in response to anoxia. Anaerobiosis is accompanied by the acquisition of two [4Fe 4S]2+ clusters per FNR dimer and the ability to bind DNA site-specifically. Oxidation of the [4Fe-4S]2+ form of FNR by O2 produced a non-DNA-binding, transcriptionally inactive form which also contains an iron-sulfur cluster, recently identified by Mossbauer spectroscopy as a [2Fe-2S] cluster (Khoroshilova et al., 1997, PNAS. 94, 6078). Complete conversion needed at least 2.5-3.0 molecules of O2 per [4Fe-4S]2+ cluster. Using sub-stoicheiometric amounts of air saturated buffer, stable equilibria were established in which the [4Fe-4S]2+ and [2Fe-2S]2+ forms co-exist and no EPR detectable free ferric ions were released. In contrast, a 20-fold molar excess K3Fe(CN)6 was required to oxidise the [4Fe 4S]2+ cluster and in this case, ferric ions were released. FNR is therefore a sensitive O2 sensor. PMID- 9373184 TI - Reconstitution of peptide-binding activity by TAP in proteoliposomes. AB - The purification and functional reconstitution of the transporter associated with antigen processing (TAP) is crucial for a complete molecular understanding of its action. Here, we report the conditions for the successful solubilization of human TAP from cellular membranes while maintaining TAP peptide-binding activity. In addition, solubilized TAP was incorporated into proteoliposomes and shown to possess specific peptide-binding activity. These studies provide the foundation for future attempts to achieve the complete functional reconstitution of TAP, which includes peptide transport. PMID- 9373185 TI - Peptide binding and photo-crosslinking to detergent solubilized and to reconstituted transporter associated with antigen processing (TAP). AB - The transporter associated with antigen processing (TAP) is essential for peptide loading onto major histocompatibility (MHC) class I molecules by translocating peptides into the endoplasmic reticulum. We have explored the conditions for detergent solubilization of functionally active, heterologously expressed human TAP from microsomal membranes. The efficiency to solubilize TAP was tested for a variety of detergents as well as for different solubilization conditions. The activity of the solubilized TAP complex was analyzed over time, using a non radioactive crosslinking assay with a photo-activateable peptide, in the presence or absence of external lipid. The detergent CHAPS was found optimally to retain activity and thus allowed us to reconstitute detergent-solubilized, active TAP into proteoliposomes. PMID- 9373186 TI - Specific reg II gene overexpression in the non-obese diabetic mouse pancreas during active diabetogenesis. AB - The reg gene, previously described in islets of 90% pancreatectomized and nicotinamide-treated rats, has been shown to be expressed in many pharmacological or surgical animal models of beta cell regeneration. We have studied the non obese diabetic (NOD) mouse, which represents a good model of spontaneous autoimmune diabetes in which regenerative processes have recently been demonstrated. Two reg genes have been described in the mouse genome, both recognized by the human reg cDNA. In a previous work, using the human probe, we have demonstrated a strong correlation between pancreatic reg gene expression and the likelihood of developing diabetes. In the present study, we have examined the respective levels of both mouse reg I and reg II mRNA in the NOD mouse pancreas using their specific cDNA probes. We found that reg II expression was specifically prevalent compared to reg I, irrespective of sex or state of the disease. Reg II mRNA was particularly increased in overtly diabetic female mice and in cyclophosphamide-treated male mice. These data underline the need to study separately the reg genes using specific probes and show that both reg genes are subjected to various regulations, strongly suggesting that their physiological functions may be different. PMID- 9373187 TI - Effect of the chaperone-like alpha-crystallin on the refolding of lysozyme and ribonuclease A. AB - Alpha-crystallin exhibits chaperone-like properties in preventing aggregation of proteins. We have studied the effect of alpha-crystallin on the refolding of denatured-disulfide intact and denatured-reduced lysozyme and RNase A. Alpha crystallin does not have any effect on the refolding of both the denatured disulfide intact enzymes. However, it inhibits the aggregation and oxidative renaturation of denatured-reduced lysozyme. Interestingly, it has no effect on the refolding of denatured-reduced RNase A. In order to probe the molecular basis of this differential behavior of alpha-crystallin towards lysozyme and RNase A, we have carried out circular dichroism and fluorescence studies on the refolding of denatured-reduced RNase A. It exhibits an extended conformation with little difference in the exposed hydrophobicity during the refolding process. We have earlier shown the presence of an aggregation-prone, refolding-competent, molten globule-like intermediate on the refolding pathway of lysozyme. Alpha-crystallin binds to this intermediate, prevents its aggregation and inhibits its oxidative refolding. It was earlier believed that alpha-crystallin, unlike other chaperones, does not recognize intermediates on the refolding pathway but only recognizes intermediates on the unfolding pathway of proteins. Our present study clearly shows that it recognizes the refolding intermediates as well. PMID- 9373188 TI - Identification of functional synergism between monoclonal antibodies. Application to the enhancement of plasminogen activator inhibitor-1 neutralizing effects. AB - The serpin plasminogen activator inhibitor-1 (PAI-1), an important risk factor for thrombotic disease can be neutralized by distinct mechanisms. We hypothesized that the combination of two compounds, with PAI-1 neutralizing properties based on different mechanisms, may result in a synergistic effect. Therefore, seven monoclonal antibodies with PAI-1 neutralizing properties were pairwise evaluated for the possible presence of synergistic or antagonistic effects. Out of 21 combinations, three particular combinations, i.e. MA-33H1/MA-33B8, MA-33B8/MA 7D4B7, and MA-7D4B7/MA-33H1 exhibited strong synergistic effects in comparison with their properties when evaluated individually. The observed synergism resulted in a maximum enhancement between 2- and 5-fold (P < 0.05, vs. theoretically expected effect calculated based on additive effects). Strikingly, synergism was only observed between monoclonal antibodies directed against different epitopes and with different molecular mechanisms of PAI-1 neutralization. This phenomenon of synergism opens new perspectives in the design of therapeutic or preventive strategies aimed at enhancing endogenous fibrinolysis through modulation of PAI-1 activity. PMID- 9373189 TI - Presence of paraoxonase in human interstitial fluid. AB - Human serum paraoxonase (PON1) is postulated to have anti-atherosclerotic properties through its ability to prevent lipid peroxide generation on LDL. However, in order to perform this role it must be present in interstitial fluid, to prevent LDL oxidation which takes place in the sub-intimal space of the artery wall. The PON1 activity in interstitial fluid was 15.7 (2.3-183.0) (median (range)) nmol/min/ml compared to 105.3 (74.6-323.9) nmol/min/ml in serum. The PON1 concentration in interstitial fluid was found to be 20.2 (1.1-78.1) microg/ml (median (range)) compared to 109.6 (11.1-485.7) microg/ml in serum. Interstitial fluid PON1 concentration was dependent on the interstitial fluid apo AI concentration (r = 0.690, P < 0.005) indicating PON1 remained associated with HDL. However, the ratio of PON1 concentration to apo AI was lower in interstitial fluid (0.60 +/- 0.20) than in the serum (0.95 +/- 0.18) (P < 0.001) indicating sequestration of PON1 in the sub-intimal space. Therefore, PON1 is present and active in interstitial fluid where it can perform its anti-atherosclerotic function. PMID- 9373190 TI - Modulation of the DNA binding activity of transcription factors CREP, NFkappaB and HSF by H2O2 and TNF alpha. Differences between in vivo and in vitro effects. AB - Human endothelial cells exposed to H2O2 showed reduced CREP DNA binding activity, enhanced HSF activation, and no induction of NFkappaB binding activity. Interestingly, H2O2 was able to induce NFkappaB subunit p65 translocation in the nucleus. In contrast, cells exposed to TNF alpha showed enhanced CREP binding activity, activation of NFkappaB and no induction of HSE-HSF complex. Addition of H2O2, diamide and iodoacetic acid to the binding reaction mixture markedly reduced the DNA binding ability of the three transcription factors. Thus free sulfhydryls were important in DNA binding activity of CREP, NFkappaB and HSF, and the lack of induction of NFkappaB by H2O2 in intact cells was likely caused by oxidation on a thiol, and not by a deficiency in the activation pathway. PMID- 9373191 TI - The human thrombin receptor gene and the 5q-syndrome. AB - The human thrombin receptor gene has been localized to band q13 of chromosome 5, a site that is at or contiguous to the common proximal breakpoint found in the majority of patients with interstitial deletions involving 5q (5q- syndrome; refractory anemia with dysmegakaryocytopoiesis). Recent evidence suggests that the thrombin receptor may represent the prototype of an emerging family of proteolytically activated receptors that may be clustered within this region of the human genome. The phenotypic heterogeneity evident in patients with the 5q- syndrome may be explained by two (or more) distinct molecular defects-one associated with megakaryocytic dyspoiesis and the other dysregulated myeloid growth potentially related to development of leukemogenesis. Because the thrombin receptor is known to mediate proliferative effects on diverse cells including vascular smooth muscle cells, endothelial cells and megakaryocytes, we have studied the role of this receptor in the pathogenesis of this syndrome using fluorescent in situ hybridization (FISH) analysis. Dual-label FISH using a q12 specific genomic fragment and the TR gene was completed using interphase and metaphase analysis from seven patients with a del(5)(q13q33). These data unequivocally demonstrate that the thrombin receptor gene is located centromeric to the common proximal breakpoint, and is grossly present in the seven patients containing this specific interstitial deletion. Additionally, one patient demonstrated a small proximal rearrangement, most likely representing a paracentric inversion, which has not previously been described within the intact region centromeric to the breakpoint. The biological properties of proteolytically activated receptors are reviewed in more detail, with a focus on the molecular genetics of the thrombin receptor and its potential role in megakaryoctyopoiesis. PMID- 9373193 TI - Differentiation of myeloid cells and 1,25-dihydroxyvitamin D3. AB - It is well established that 1,25(OH)2D3 induces monocyte/macrophage (Mo/Mphi) colonies when added to culture of granulocyte/macrophage progenitors. Recently, we demonstrated that one of the target cells of 1,25(OH)2D3 in Mo/Mphi differentiation is the neutrophilic promyelocyte that is believed to belong to the neutrophilic lineage. This fact overthrows the established theory that normal hematopoietic precursors are committed to respective cell lineages and do not deviate from their own lineage. The lineage switching from the promyelocyte to Mo/Mphi was suggested to be operating in vivo because 1,25(OH)2D3 is a physiological substance produced by Mphi. More recently, we have shown that transient exposure (24 h) of promyelocytes to 1,25(OH)2D3 causes Mo/Mphi differentiation. This strategy could be useful for examining the effects of 1,25(OH)2D3 on the growth and differentiation of normal myeloblasts and myeloid progenitor cells. Recent advances in molecular biology have enabled investigators to identify a number of genes involved in Mo/Mphi differentiation induced by 1,25(OH)2D3. Some of these may be the determinant genes for Mo/Mphi differentiation; however, further studies are required to determine the underlying mechanisms of Mo/Mphi differentiation. PMID- 9373192 TI - Modulation of interleukin-6/interleukin-6 receptor cytokine loop in the treatment of multiple myeloma. AB - Interluekin-6 (IL-6)/IL-6 receptor (IL-6R) play a major role in autocrine/paracrine growth regulation of myeloma cells and are the central mediators for bone destruction and other systemic manifestations of multiple myeloma. Modulation of the IL-6/IL-6R cytokine loop thus represents a rational therapeutic approach. We updated and reviewed the studies on the agents that targeted IL-6/IL-6R modulation and the results of selected clinical trials. Extensive in vitro studies with human myeloma cell lines or primary myeloma explants have shown that components of this cytokine loop could be modulated by various agents, and such modulation is associated with inhibition of myeloma cell growth. The purported mechanisms of action of these agents, down-regulation or neutralization of IL-6 and/or IL-6R and the interruption of IL-6 binding to IL-6R or gp 130 signal transducer, with possible exception for glucocorticoids and specific antibodies, remain to be formally proven. Clinical trials showed largely limited benefits of these agents. Given tumor cell heterogeneity and the complexity of inter-connected cytokine network in vivo, the future emphasis should be on the strategy of combination treatment that would modulate this cytokine loop at multiple sites. Further advances in delineating IL-6 and related cytokine signal transduction pathways should also suggest other targets for therapeutic intervention. PMID- 9373194 TI - Interleukin-15: a novel cytokine with regulatory properties on normal and neoplastic B lymphocytes. AB - IL-15 is a recently discovered cytokine that shares biological activities with IL 2. Although the biological functions displayed by these two molecules overlap to some extent, they are produced by different cell types and bind to distinct receptorial structures. Both cytokines transduce signals through the beta (p75) and gamma (p64) chains of the IL-2R system, but IL-15, like IL-2, binds to its own specific alpha chain, referred to as IL-15Ralpha. Similarly to IL-2, IL-15 is able to trigger both the proliferation and immunoglobulin production by normal B lymphocytes. These biological functions may be acquired however only when B-cells have been preactivated in vitro with polyclonal mitogens, or alternatively, when they are cultured in association with other stimuli. By contrast, leukemic cells from patients with chronic B-cell malignancies, including B-cell chronic lymphocytic leukemia and hairy cell leukemia, proliferate to IL-15 regardless of in vitro preactivation. This peculiar IL-15 responsiveness distinguishes malignant B-cells from normal B-lymphocytes. Furthermore, the proliferation elicited by IL-15 in B-CLL and HCL is mainly related to the presence of the beta and gamma chains of the IL-2R system on malignant B-lymphocytes. PMID- 9373196 TI - Significance of rearrangement of the BCL6 gene in B-cell lymphoid neoplasms. AB - Chromosomal translocations involving 3q27 are among the most common recurring translocations in non-Hodgkin's lymphoma (NHL) of B-cell phenotype. Molecular cloning of junctional areas of the translocations resulted in isolation of the BCL6 gene adjacent to the breakpoint cluster on 3q27. The gene encodes a zinc finger transcription factor which is expressed in nuclei of germinal center B cells. Rearrangement of BCL6 was observed in 6.4 to 14.3% of follicular lymphomas and 28.6 to 35.5% of diffuse large cell lymphomas; regarding the latter, a Japanese series showed a lower incidence. Survival curves suggested that NHL carrying rearrangement of BCL6 and lacking that of BCL2 is curable by chemotherapy. Detailed analysis of the vicinity of translocations showed that the 5' untranslated region of BCL6 was replaced by heterogeneous promoters not only from immunoglobulin genes but also from many previously uncharacterized loci. Bcl 6 protein is expressed in NHL of follicular center B-cell origin, independently of the presence or absence of BCL6 rearrangement. At present, limited information is available about the functional consequences of the rearrangements and, in particular, about their ultimate implications for lymphomagenesis. PMID- 9373195 TI - Clinical indications of multiple integrations of human T-cell lymphotropic virus type I proviral DNA in adult T-cell leukemia/lymphoma. AB - In this review, we discuss the possible relationship between the clinical characteristics and the multiple integration of human T-cell lymphotropic virus type I (HTLV-I) proviral DNA in patients with adult T-cell leukemia/lymphoma (ATL). Some patients with ATL show multiple HTLV-I integrations and exhibit clinical characteristics unlike those of ATL patients who show the typical integration of a single provirus. Multiple HTLV-I integrations can be detected by Southern blotting as multiple bands having varied intensities. These multiple integration conditions can arise from one tumor cell clone carrying multiple copies of the provirus, or from multiple cell clones, each carrying one copy of the provirus. The former patients manifest an extremely aggressive clinical course with the infiltration of unusual organs such as the retina and uvea. The latter patients show an indolent clinical course with skin lesions. These findings suggest that the clinical implications for multiple HTLV-I integrations exist in ATL. This may be one of the explanations for the heterogeneous findings in the disease. Such observations may provide information linking viral integration with clinical manifestations, and improve our understanding of the pathogenesis of ATL. PMID- 9373197 TI - Growth factor administration following autologous peripheral blood progenitor cell transplantation. AB - Hematopoietic growth factor (HGF) administration following autologous peripheral blood progenitor cell transplantation (APBPCT) is a current approach for shortening the duration of high-dose chemotherapy-induced transient peripheral pancytopenia. Several published clinical experiences and a retrospective study reported here show that recombinant human granulocyte colony stimulating factor (rhG-CSF) or recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) administration potentiates polymorphonuclear leukocyte (PMN) and white blood cell (WBC) recovery with some clinical benefits mainly related to the reduction of infectious complications during the shortened period of neutropenia. However, this therapeutic strategy does not produce any enhancement of platelet (PLT) recovery or potentiation of red cell production. Conversely, a recent phase I/II study carried out in our institution showed that the combined administration of rhG-CSF and recombinant human erythropoietin (rhEPO) is able to potentiate trilineage hematopoietic recovery with a reduction of PLT transfusions and to considerably simplify the clinical management of patients as compared to patients treated with APBPCT alone. The post-APBPCT administration of rhEPO with rhGM-CSF decreased the number of days with WBC < 1 x 10(9)/L but failed to produce any appreciable effect on PLT recovery. Both combined treatments significantly reduced the patients' hospital stay and allowed the abrogation of systemic antibiotic administration following APBPCT. A further group of patients were treated with the combined administration of rhEPO, rhG-CSF and rhGM-CSF; they did not show a faster hematopoietic recovery than rhG-CSF plus EPO treated patients and a consistent hyperthermia was observed in most patients as a prominent side effect. Future prospective randomized studies will clarify the efficacy of HGF administration following APBPCT. Moreover, further improvements in the hematopoietic support of transplanted patients may be obtained when stem cell factor, flt3/flk2 tyrosine kinase ligands or megakaryocyte growth and development factor will become clinically available. PMID- 9373198 TI - Optimal regimens for the mobilization and collection of peripheral blood progenitor cells from normal donors. AB - The optimisation of mobilisation and collection of progenitor cells from normal donors remains a central issue in all investigations of allogeneic peripheral blood progenitor cell transplantation. It is important that donor issues remain a major concern and that they carry no more hazard to the donor than routine bone marrow harvesting. This paper reviews current data concerning these issues. PMID- 9373199 TI - The functional phenotype of the primitive plasma cell in patients with multiple myeloma correlates with the clinical state. AB - The malignant plasma cells from patients with multiple myeloma display considerable phenotypic heterogeneity. All plasma cells express high intensity CD38 (CD38++), cytoplasmic immunoglobulin and either kappa or lambda light chains. Subpopulations of mature (CD45-), immature (CD45+) and primitive (CD45++, CD19+) plasma cells can be defined but little is known about the functional differences and clinical significance of these subpopulations. Three colour flow cytometry and permeabilisation was used to determine the expression of functionally important antigens in plasma cell subpopulations. These antigens included the labelling index (LI, bromodeoxyuridine), number of nucleoside transporter per cell, p-glycoprotein (JSB-1), and oncoprotein expression (c-myc, c-fos, c-neu, bcl-2, p-ras, p53m, p-53w, and Rb). In progressive disease there was an increase in the absolute number but not the percentage of CD45++ plasma cells. There was a significant difference in the mean LI of the CD38++, CD45++ population in progressive disease compared with stable disease (9.2% vs 2.2%; z = 19.9, p < 0.001). The LI of CD45++ cells ranged up to 45% and provided a better correlation with disease status than the LI of the total cell population. Any increase in nucleoside transporters or p-glycoprotein expression was almost entirely attributable to an increase in the primitive plasma cell population. In 96% (n = 28) of samples from patients in progressive disease there was at least one abnormality in the functional phenotype of the primitive plasma cells. This is in contrast with 44% of samples from patients in stable disease (n = 58). These studies suggest that the functional phenotype of the primitive plasma cell determines the clinical phenotype of patients with myeloma. PMID- 9373200 TI - FLAG is a useful regimen for poor prognosis adult myeloid leukaemias and myelodysplastic syndromes. AB - Forty patients, with mainly poor risk haematological malignancies, were given the new regimen FLAG, comprising fludarabine, arabinosyl cytosine and G-CSF. Twenty four patients had acute myeloid leukaemia (AML), 8 patients myelodysplastic syndrome (MDS) and a further 8 patients had a variety of other haematological malignancies. The response rates for 19 relapsed and 4 refractory AML patients were 68% and 100% respectively and comparable to those attained using other regimens, although the numbers are small. Of 8 patients with MDS, 7 showed some response with 4 remaining in an improved disease status 5-12 months after FLAG. Follow-up has been too short thus far to provide any survival data in both patient groups. In general, the other smaller group of 8 patients (3 transformed chronic myeloid leukaemia (CML), 3 acute lymphoblastic leukaemia (ALL), 2 granulocytic sarcoma (GS) did poorly with response shown in 1 only. The regimen was well tolerated with 4 procedure-related neutropenic deaths. The neutropenic and thrombocytopenic periods are generally short when compared with those from current protocols. The overall modest toxicity may encourage combination with other anti-leukaemic agents and be of particular use in the aged or heavily pre treated patients. Preliminary results may favour the setting up of controlled trials to properly evaluate the benefit of FLAG. PMID- 9373202 TI - Excessive proliferation matched by excessive apoptosis in myelodysplastic syndromes: the cause-effect relationship. AB - The paradox of pancytopenia despite cellular bone marrows (BM) was investigated in 120 patients with myelodysplastic syndromes (MDS). Detailed cell cycle kinetics were examined following in vivo infusions of iodo--and/or bromodeoxyuridine (IUdR/BrdU), while the incidence of apoptosis was measured by in situ end labeling (ISEL) of fragmented DNA. Results showed that MDS are highly proliferative disorders with an equally high incidence of apoptotic intramedullary cell death accounting for the paradox of cellularity/cytopenia. By double-labeling BM biopsy sections for ISEL/BrdU we found the peculiar situation of "signal antonymy" where S-phase cells were frequently apoptotic, a phenomenon so far only seen in MDS biopsies. The cause-effect relationship of this excessive proliferation/apoptosis is discussed at length. PMID- 9373201 TI - Autologous bone marrow transplantation in advanced Hodgkin's disease. AB - Autologous bone marrow transplantation (ABMT) has been proposed as an alternative treatment of resistant/refractory Hodgkin's disease (HD). Thirty-seven patients in various phases of HD underwent autografting in our Center: fourteen received a CBV conditioning regimen, the others BCNU or VP16 followed by cyclophosphamide and TBI. Three patients died before engraftment, 28 (75.67%) achieved CR and 6 showed persistent disease. As of March 1996, 18 patients had died and 13 were in continuous CR. The median event-free survival (EFS) and 3-year EFS chances were respectively 9 months and 31.3% in the series as a whole, 14 months and 40% in primary resistant disease, 9 months and 28.4% in responsive relapse, and 3 months and 22.2% in resistant relapse. As many of these patients had failed to respond to third-line therapies, their EFS figures are primarily attributable to the therapeutic efficacy of ABMT. Furthermore, since the EFS curves are better in patients seemingly characterized by a lower chance of chemoresistance, our data favour the use of ABMT in the earlier phases of HD. PMID- 9373203 TI - Simultaneous expression of P-glycoprotein and BCL-2 in acute myeloid leukemia blast cells. AB - High expression of the multidrug resistance gene product P170, and of the oncoprotein bcl-2 have been associated with in vitro resistance to chemotherapeutic agents and with poor clinical outcome in acute myeloid leukemia (AML). More recently, it has been shown that autonomous proliferation of blast cells in liquid culture was also predictive of poor prognosis. In a series of 72 adult AML cases at diagnosis, we studied by flow cytometry the expression of P170 and bcl-2 proteins, together with autonomous growth of leukemic cells in liquid culture. Cases were classified as exhibiting no proliferation (N = 29), intermediate proliferation (N = 25) and high proliferation (N = 18). We observed a significant correlation between the percentage of cells in each sample expressing P170 and bcl-2. This was confirmed by double staining techniques showing that both antigens were present in the same cells. We also observed a significant association between growth pattern and P170 or bcl-2 expression. All patients were treated by intensive chemotherapy including an anthracycline drug and cytarabine. The blasts of patients achieving complete remission (N = 47) were less frequently positive for CD34, P170 and bcl-2 than those from patients who did not. Growth pattern also influenced significantly CR. In univariate analysis, CD34, P170 and bcl-2 expression, as well as growth pattern, significantly influenced survival. However, in multivariate analysis P170 expression remained the only significant factor, bcl-2 (or proliferation) having no independent value. Our study confirms the prognostic value of P170 and bcl-2 expression as well as the value of spontaneous proliferation and suggests that several drug resistance mechanisms are implicated concomitantly in AML. PMID- 9373204 TI - Chromosome 8 tetrasomies and pentasomies--a clonal abnormality closely associated with acute monocytic leukaemia. AB - We report four cases of polysomy 8 (one tetrasomy and three pentasomies) observed in acute monocytic leukemia (FAB M4 and M5). Three of them showed a rearrangement of 11q23 identified by conventional cytogenetic analysis and/or chromosome painting. Our cases as well as a review of the literature, suggest that polysomy 8 is preferentially associated with monocytic differentiation (24/31). These polysomies have been observed in 21 de novo leukemias and in 10 secondary hematological disorders. A 11q23 rearrangement has been detected in 9 out of 32 patients, by conventional cytogenetic techniques in 7 and by FISH in 2. We suggest that these cases should be analysed by FISH and molecular studies in order to detect a rearrangement of MLL/11q23. Monocytic differentiation is often associated with a change of the MLL gene and the polysomy 8 might be a particular clonal evolution secondary to 11q23 abnormality. PMID- 9373206 TI - Auto-tumor reactive cytotoxic T-cell responses in B-cell non-Hodgkin's lymphoma. AB - We have generated cytotoxic T-lymphocytes (CTLs) from the peripheral blood (PB) of eight B-cell non-Hodgkin's lymphoma (NHL) patients by in vitro coculture with autologous fresh tumor cells. Their functional activity was assessed in 51Cr release assay and was found to be MHC class I restricted. Our results indicate the presence of T-cells cytotoxic for autologous tumor cells in the PB of these patients but these were relatively small numbers in small lymphocytic lymphomas (SLLs). Treatment of fresh tumor cells with rIFN-gamma and rTNF-alpha alone, or in combination significantly increased their susceptibility in 4/5 cases of SLLs, and a case of diffuse large cell lymphoma and Burkitt lymphoma (BL), while, B cell lymphoma, rich in T-cells, did not show any appreciable increase. Fresh tumor cells were also analysed for MHC class I and ICAM-1 antigens by flow cytometry, in 5/8 cases before and after cytokine treatment. Significant upregulation of MHC class I antigens but with no detectable change in ICAM-1 observed in a case of SLL and BL, correlated with enhanced susceptibility. These findings suggest the possible role of MHC class I antigens in the cytotoxic susceptibility of autologous tumor cells in B-cell NHL. PMID- 9373205 TI - Cytokine priming of the granulocyte respiratory burst in myelodysplastic syndromes. AB - Increased susceptibility to infections in patients with myelodysplastic syndromes (MDS) is thought to be due to neutropenia as well as functional abnormalities of neutrophils. In the present study we examined the effect of two different stimulants (fMLP, PMA) and three cytokines (alphaTNF, G-CSF and GM-CSF), both singly and in combination on granulocyte (RB) in 25 MDS patients compared to seven healthy controls. Single fMLP and PMA-stimulation showed similar results for both groups. Preincubation with cytokines enhanced fMLP-stimulated RB in most MDS patients and controls, but in patients to a significantly lesser extent when compared to the control group (p < or = 0,05). Combinations of alphaTNF + GM-CSF and alphaTNF + G-CSF were highly synergistic in priming fMLP-stimulated burst in both groups. But again, as with the single cytokine priming this effect was markedly reduced in MDS patients compared to controls (p < or = 0,05). A specific priming defect for one of the cytokines or a cytokine combination could not be demonstrated. Serum alphaTNF levels were measured in 18 and neutrophil alkaline phosphatase (NAP) index in 23 patients. Results did not correlate with variations of the RB in MDS patients. We conclude that reduced alphaTNF, GM-CSF and G-CSF priming of granulocyte RB is a frequent finding in MDS and may contribute to the enhanced susceptibility to bacterial infections. PMID- 9373207 TI - Primary pulmonary lymphoma--clinical review from a single institution in Singapore. AB - Primary pulmonary lymphoma is a rare and vexing subset of extranodal non Hodgkin's lymphoma. We report 11 cases and provide a brief literature review. We also highlight an unusual case of a relapsed peripheral T-cell primary lung lymphoma that underwent apparent spontaneous remission. Eleven cases of primary pulmonary lymphoma treated in our institution were studied for their clinical characteristics, behaviour, response to treatment and clinical outcome. The median duration of follow up was 26 months. The mean age was in the 50s and the presenting symptoms generally respiratory and non-specific. LDH levels did not correlate with either stage or grade of disease. Lower lobe involvement was most common and nodules and mass-like lesions the main radiologic feature. Small lymphocytic lymphoma accounted for the majority of cases and were indolent in behaviour. Good symptom control and radiologic response was achieved with chemotherapy in disseminated low grade lung lymphomas. Combination chemotherapy was effective in the aggressive lymphomas. In conclusion, Small lymphocytic lymphoma of the lung is an indolent disease with a long symptom-free survival even after recurrence. Our series confirms the clinical characteristics of primary pulmonary lymphoma. The role of Ling Zhi in effecting the spontaneous remission in the peripheral T-cell lymphoma is speculative. PMID- 9373208 TI - Ultrastructural observations on bone marrow cells of 26 patients with myelodysplastic syndromes. AB - Bone marrow aspirates from 26 patients with myelodysplastic syndrome (MDS) were examined using transmission electron microscopy. The red blood cell precursors in 9 patients showed varying degrees of dyserythropoiesis including the presence of 2 or more nuclei, nuclei with bizarre shape and iron deposits in the mitochondria. The myeloid series showed a tendency to hypogranulation (5 patients) and in 2 patients there were signs of platelet phagocytosis. The monocytes had a normal ultrastructure except for one patient with chronic myelomonocytic leukemia (CMML) with transformation to acute myelo-monocytic leukemia (AMML). In this case, the monocytes were immature, with markedly convoluted nuclei and scanty heterochromatin. The lymphocytes also had a normal appearance, except for one patient in whom the lymphocytes were immature, with lobulated nuclei and suggested transformation of MDS to acute lymphoblastic leukemia. The plasma cells in 3 patients were slightly increased in number and in one of them Russell bodies were seen both in the cytoplasm and the nucleus. The megakaryocytic series showed a shift to the left and in one patient there were signs of emperipolesis. The alterations in the hematopoietic cells in patients with MDS described in the present study indicate that the electron microscope may supplement light microscopic findings and help in the establishment of a correct diagnosis. This may be also evident in those cases of MDS in which the very early stages of leukemic transformation cannot be easily detected by light microscopy. PMID- 9373209 TI - Quantitative flow cytometry can predict childhood acute lymphoblastic leukaemia presenting with aplasia. AB - Acute lymphoblastic leukaemia (ALL) presenting as a transient pancytopenia is known to occur in children and less commonly in adults. The period of pancytopenia usually resolves after about 5-38 weeks, to be followed by overt ALL. The pathogenesis is not known and there are no specific cytogenetic abnormalities. Diagnosis is often difficult during the period of bone marrow hypoplasia. Quantitative flow cytometry can help to establish early diagnosis, and can be used on more patients presenting in a similar way. PMID- 9373210 TI - Chemotherapy alone may be an efficient alternative in the treatment of early stage Hodgkin's disease if optimal radiotherapy is not available. AB - Because radiotherapy (RT) equipment technology in some developing countries is outdated, its side effects are more frequent and severe and its efficacy suboptimal, whereas chemotherapy (CT) meeting international standards is generally more consistent. With this in mind, we treated 29 patients with stages I and II Hodgkin's disease with the MOPP or the MOPP/ABV hybrid schedule without prior staging laparotomy. The complete remission rate was 96%: five patients relapsed and of these, two died and three were rescued with CT, in one case followed by an autologous stem cell autograft. The median follow-up is 54 months (range 9 to 126), the overall survival of the group 88% at 126 months, and the relapse-free survival 72% at 110 months. Conventional CT alone has been shown to be useful in achieving acceptable long-term results. This observation could be important in circumstances where RT is unavailable or of suboptimal quality. PMID- 9373211 TI - Non-secretory multiple myeloma with multinucleated giant plasma cells. AB - We report a case of non-secretory multiple myeloma with unusual cytological features. The plasma cells were multinucleated and contained up to forty nuclei. All nuclei had regular outlines without multilobulated and convoluted slopes. DNA content measurement demonstrated that all nuclei of uni- and multinucleated cells were diploid. All plasma cells contained cytoplasmic alpha chain but light chains and their corresponding transcripts were absent. There is no clear explanation concerning multinuclearity. In addition, hypotheses regarding non-secretion of immunoglobulin in non-secretory multiple myeloma and in other B-cell neoplasias are discussed. PMID- 9373212 TI - Successful treatment of disseminated central nervous aspergillosis in a patient with acute myeloblastic leukemia. AB - Invasive opportunistic mycoses are common complications in patients suffering from hematological disorders. Brain abscesses in the immunocompromised host are known to be most frequently caused by fungi of the Aspergillus species and are often associated with concomitant pulmonary disease. As the penetration of the currently available antifungal agents into the brain tissue is limited, only very few patients have been described to survive this life-threatening condition. We report the case of a 62 year old female patient who presented with multiple aspergillus brain abscesses during prolonged neutropenia following induction chemotherapy for acute myeloblastic leukemia and was successfully treated with high dose (8 mg/kg/day) liposomal amphotericin B. PMID- 9373213 TI - Analysis of Vbeta4 T cell receptor CDR3 repertoire in BALB/c and (NZB x NZW)F1 mice. AB - To examine the unique TCR repertoire in auto-immune-prone (NZB x NZW)F1 (B/WF1) mice, we analysed the Vbeta4 CDR3 region of TCRbeta chain in spleens of young (1 month old) and aged (6 month old) BALB/c and B/WF1 mice. Total RNA from spleens was used for cDNA synthesis and TCRVbeta4 PCR products were cloned and sequenced. Young B/WF1 mice showed high frequency (38.5%) of anionic amino acid residues at position beta100 in TCRVbeta4 chain compared to that (19.0%) in young BALB/c mice. Aged BALB/c mice and B/WF1 mice showed increase of frequency (38.1 and 51.9%, respectively) of anionic residues at beta100. These results indicate that Vbeta4-T cells that have anionic residues at beta100 in CDR3 region of TCRbeta chain increase with age in normal mice. Auto-immune prone mice show high frequency of anionic residues at beta100 in TCRVbeta4 chain even at the age of 1 month. These T cells may interact with cationic self-antigen(s) and might contribute to the onset and/or the progression of systemic autoimmunity in concert with other genetic elements in B/WF1 mice. PMID- 9373214 TI - Fine mapping of the epitopes of humanized anti-L-selectin monoclonal antibodies HuDREG-55 and HuDREG-200. AB - Blocking the function of L-selectin with a monoclonal antibody (mAb) is a promising way to prevent neutrophils from causing tissue damage during inflammation. HuDREG-55 and HuDREG-200 are humanized mAb which bind to human L selectin and block its function as an adhesion molecule. To understand the mechanism of the action of HuDREG-55 and HuDREG-200, we determined their epitopes on L-selectin at the amino acid level. The analysis of human E- and L-selectin chimeric proteins demonstrated that the lectin domain of L-selectin is necessary for the binding of HuDREG-55 and HuDREG-200. Mutational analysis of Escherichia coli-expressed L-selectin showed that HuDREG-55 binding is sensitive to amino acid changes at positions 11, 56, 87, 89, 105, 107 and 111 (counting from the amino-terminus of mature L-selectin) while HuDREG-200 binding is sensitive to amino acid changes at 45, 46 and 47. Both epitopes are located close to the predicted carbohydrate binding site, indicating that HuDREG-55 and HuDREG-200 block the function of L-selectin by directly inhibiting the binding to carbohydrate ligands. PMID- 9373215 TI - Differential sensitivities to hyperbaric oxygen of lymphocyte subpopulations of normal and autoimmune mice. AB - We studied the effect of exposure to hyperbaric oxygen (HBO): 2.8 atm absolute 100% oxygen for 4 h daily over 3-7 days, on the immune system of normal (BALB/c and MRL- +/+) and autoimmune MRL-lpr/lpr) mice. In HBO exposed BALB/c mice, we observed a remarkable decrease in the cell population of the spleen and thymus. We found that the sensitivity to HBO varied among subpopulations of lymphocytes. For example, CD4+ CD8+ double positive cells in the thymus and B220+ B cells in the spleen were more sensitive than CD4+ or CD8+ single positive T cells in the thymus, and Thy-1+ T cells in the spleen, respectively. Accordingly, despite the decrease in total cell number in the spleen, the proliferative response of T cells from the spleen to Con A was not impaired in the HBO exposed mice. Exposure of MRL-lpr/lpr mice to HBO caused a marked reduction of weight and cell population of the otherwise enlarged spleen and lymph nodes, and amongst others of percentages of B220+Thy-1+ double positive abnormal cells. These results suggest the HBO therapy may be applicable for the treatment of some autoimmune diseases. PMID- 9373216 TI - Enrichment of antigen-specific T lymphocytes by panning on immobilized MHC peptide complexes. AB - Numerous studies have focused on characterizing and monitoring antigen-specific T cells during the course of an immune response. Mostly indirect methods were used to circumvent the low frequency of T cell precursors and the inherent complexity of T cell receptor (TcR)-MHC-peptide interactions. Here, we took advantage of peptide-specific adhesion induced by immobilized MHC-peptide complexes. We describe a simple technique which allows enrichment in antigen-specific T lymphocytes among a heterogeneous CD8+ T cell population. Enrichment of T cells according to their specificity should facilitate their characterization and provide an attractive tool for immunotherapy. PMID- 9373217 TI - The immunosuppressive peptide of HIV-1 gp41 like human type I interferons up regulates MHC class I expression on H9 and U937 cells. AB - Based on our findings that the immunosuppressive peptide (ISP, amino acids (aa) 583-599) of human immunodeficiency virus type 1 (HIV-1) gp41 shows sequence similarity with human type I interferons (IFN-alpha and IFN-beta) and HIV-1 soluble gp41 (sgp41, aa 539-684) enhanced cell surface expression of major histocompatibility complex (MHC) class I molecule on human H9 (T cells), Raji (B cells) and U937 (monocytic cells) cells, we examined the effect of HIV-1 immunosuppressive peptide on the surface expression of MHC class I molecules on H9 and U937 cells. Flow cytometry analysis demonstrated that ISP-BSA (conjugate) could enhance MHC class I expression by about 40% on H9 cells and by about 45% on U937 cells, while monomer ISP (not conjugated) and EDCI-treated carrier protein (BSA-EDCI) did not increase the expression. By comparison, human type I interferons, IFN-alpha and IFN-beta, showed similar effects (enhanced the expression by about 40-60%) to ISP-BSA on the MHC class I expression on H9 and U937 cells. The results suggest that HIV-1 gp41 in a polymerized form by its immunosuppressive domain upregulates human MHC class I expression. The basis for this similar effect of HIV-1 gp41 and IFN-alpha and -beta, i.e. upregulation of MHC class I molecule expression, may be based on the sequence-similarity between these otherwise different molecules. PMID- 9373218 TI - Visualization of peptides derived from liposome-encapsulated proteins in the trans-Golgi area of macrophages. AB - Exogenous proteins are generally not presented through the major histocompatibility complex (MHC) class I pathway, yet several recent studies show that particle-associated antigens induce a CD8+ T-cell response. Therefore, a pathway must exist in vivo for the presentation of exogenous antigens on class I molecules. In the present study, we investigated the intracellular fate of liposome-encapsulated Texas Red (TR)-conjugated protein in cultured bone marrow derived macrophages (BMs). After phagocytosis of liposomes, the fluorescent liposomal protein, initially associated with the liposomal lipids in phagosomes, later entered the cytoplasm, and the processed protein was subsequently visualized in the trans-Golgi as a fluorescent peptide. Experiments performed with BMs from transporter associated with antigen processing (TAP1) knock-out mice demonstrated that the translocation of peptides into the trans-Golgi area was dependent upon TAP1 protein. We conclude that delivery of liposomal proteins or peptides to the cytoplasm of phagocytes and subsequent transport of peptides to the Golgi via the classical MHC class I pathway involving TAP proteins might explain the known propensity of liposomal antigens to induce cytotoxic T lymphocytes (CTLs). PMID- 9373219 TI - Activation of T-cells through an antigen-independent alternative pathway induces precocious sensitivity to Fas-induced apoptosis. AB - Autoreactive T-cells can be activated inadvertently during immune responses through antigen-independent pathways. It has been suggested that Fas/Fas ligand interactions may play a role in eliminating these cells, but the extent that cells activated through such alternative pathways are sensitive to Fas-induced apoptosis has not been extensively evaluated. Proliferation of peripheral blood T cells from normal individuals activated for 4 days with PHA or PMA + ionophore was not influenced by the presence of anti-Fas antibody. When the same cells were activated with soluble factors produced by previously activated T-cells (lymphostimulatory activity), anti-Fas antibodies inhibited thymidine incorporation by 74+/-4%. The presence of typical morphological changes and oligonucleosomal fragmentation of DNA indicated that the reduced proliferation resulted from apoptotic death of the lymphoblasts. Fas-sensitivity of T-cells activated by lymphostimulatory activity was first detectable 4 days after activation, and at 5 days the majority of lymphoblasts had become sensitive to Fas, whereas no evidence of sensitivity to Fas was observed for lymphoblasts generated by PHA or PMA + ionophore during the first 5 days of culture. Incubation of cells activated with PHA or PMA+ ionophore in the presence of IL-2 at concentrations 10-fold higher than that present in lymphostimulatory activity did not induce early sensitivity to Fas, indicating that exposure to IL-2 could not explain the precocious development of sensitivity to Fas seen following activation by lymphostimulatory activity. These studies demonstrate that T-cells activated through an antigen-independent 'alternative' pathway develop precocious sensitivity to Fas-induced apoptosis, which may be important in permitting the elimination of autoreactive bystander cells activated in the course of immune responses. PMID- 9373220 TI - Rapamycin antagonizes interleukin-6 mediated growth arrest and differentiation of myeloblastic M1 cells. AB - The immunosuppressant rapamycin is known to be a potent inhibitor of cytokine driven proliferation of T-lymphocytes and other cell types. Here we have examined the effect of rapamycin on the myeloblastic cell line M1 which responds to interleukin-6 (IL-6) with growth arrest and monocytoid differentiation. Single agent rapamycin led to a retardation of M cell growth. In spite of this intrinsic antiproliferative effect, rapamycin was found to abrogate IL-6 induced growth arrest. Concomitant exposure to rapamycin and IL-6 also reduced the extent of monocytoid differentiation as compared to treatment with IL-6 alone. Excess levels of the FK-506 analogue ascomycin reversed the antagonistic effect of rapamycin on IL-6 mediated growth suppression, suggesting that this biological action of rapamycin is mediated by a rapamycin/immunophilin complex. The findings demonstrate that rapamycin can also act as an antagonist of cytokine induced growth arrest and differentiation. PMID- 9373221 TI - The functional transformation of cytotoxic lymphocytes into T-suppressors under the influence of two mediators. AB - A set of CTL-lines in the system differing in the whole H-2 complex, as well as in distinct subregions of H-2, was established. These lines were routinely tested in Cr51-release assay to insure that they retained lytic activity and antigen specificity. The result of the interaction of CTL with H-2Kb-molecule and alpha1 thymosine was transition of CTL into a reversible state of anergy. A high concentration of alpha1-thymosine is necessary for this transition. Anergic CTL caused specific suppressor activity that is functional if transformation of CTL into T-suppressors took place. PMID- 9373222 TI - Anatomy and physiology of the rectum and anus. AB - Anorectal physiology is complex and involves the interaction of multiple mechanisms. Advances in physiological testing have led to a great deal of research, which has increased our knowledge of normal and disordered physiology, and modified our therapeutic approach. As a consequence, many concepts in anatomy have been revised. We have reviewed aspects of the anatomy and physiology of the rectum and anus together with the applications of the new concepts. PMID- 9373223 TI - Prophylaxis against pneumococcal infection after splenectomy: a challenge for hospitals and primary care. AB - OBJECTIVE: To evaluate prophylaxis against pneumococcal infection after splenectomy. DESIGN: Retrospective analysis. SETTING: District hospital, Denmark. SUBJECTS: 555 Patients who underwent splenectomy between 1 January 1984 and 31 December 1993. INTERVENTIONS: Splenectomy, pneumococcal vaccination. MAIN OUTCOME MEASURES: Pneumococcal vaccination rates and the time of vaccination related to different indications for splenectomy. Extent of information in hospital records about measures for prophylaxis against pneumococcal infection. Recording of splenectomy and vaccination in discharge letters. RESULTS: The total vaccination rate was 62% (344/555), but vaccination rates from 47% to 91% in five different groups of indications were observed. Patients undergoing splenectomy during cancer surgery or because of inadvertent intraoperative trauma to the spleen were particularly at risk of not being vaccinated. Vaccination rates increased from 59% to 70% during the period studied. Of the 235 patients alive on 1 April 1995, 87% (205) had been vaccinated. Only 23% of the patients were vaccinated at the appropriate time. Splenectomy had not been recorded in 10%, and vaccination status was mentioned in 35% of the discharge letters. Only 6% of the hospital records and 2% of the discharge letters mentioned one or more precautions to consider for asplenic patients. CONCLUSIONS: The pneumococcal vaccination rates of patients after splenectomy were not satisfactory. Most of patients were vaccinated at an inappropriate time in relation to the splenectomy. The discharge letters often lacked information about the patients' vaccination status. More effort is needed to reach an acceptable level of prophylaxis against pneumococcal infection after splenectomy. PMID- 9373225 TI - Enhanced polymorphonuclear leucocyte adhesion after surgical injury. AB - OBJECTIVE: To evaluate the relationship between the expression of the neutrophil adhesion receptor CD11b, functional neutrophil adhesion, and clinical outcomes in patients undergoing major surgical resections. DESIGN: Laboratory study. SETTING: University hospital, United Kingdom. SUBJECTS: 25 patients undergoing surgical resections for malignant disease. INTERVENTIONS: Blood obtained preoperatively and on postoperative days 1, 3, and 6. Neutrophils were assayed for CD11b expression in whole blood and following isolation using flow cytometry, and adhesion was measured using a chromogenic, gelatin-dependent adhesion assay, with and without stimulation by FMLP. Postoperative outcomes were classified as uncomplicated (n = 20) or sepsis according to ACCP/SCCM definitions (n = 5). RESULTS: Whole blood neutrophil CD11b expression was significantly increased on the first postoperative day and in all patients was significantly higher in the sepsis group (p < 0.001, ANOVA). There was a significant increase in CD11b expression above preoperative concentrations after separation and stimulation with FMLP only in the sepsis group, 3 and 6 days postoperatively (p < 0.01, paired t-test). Functional neutrophil adhesion was significantly higher in the sepsis compared with the uncomplicated group at all time points postoperatively (p < 0.001, two way ANOVA). CONCLUSION: Major operations are accompanied by upregulation of baseline CD11b expression mirrored by changes in neutrophil adhesion. Those patients who develop sepsis have greater degrees of CD11b expression and adhesion. These data present a potential pathophysiological role for neutrophils throughout the postoperative period in the development of sepsis and its sequelae after major operations. PMID- 9373224 TI - Pre-operative neutrophil and monocyte activation state predicts post-operative neutrophil and monocyte function. AB - OBJECTIVE: To find out if the in vitro responses of neutrophils (PMN) and monocytes preoperatively can predict their activation postoperatively. DESIGN: Prospective open study. SETTING: Teaching hospital, Ireland. SUBJECTS: 46 Patients (32 men, 14 women, mean age 65 years, range 33-85) who were to undergo elective major vascular or gastrointestinal operations for benign (n = 18) or malignant (n = 28) diseases. INTERVENTIONS: Measurement by flow cytometry of functional (PMN and monocyte respiratory burst activity) and phenotypic (expression of PMN CD 11b adhesion receptors and monocyte CD14 receptors) markers of activation. MAIN OUTCOME MEASURES: Correlation between mean channel fluorescence (MCF) preoperatively and postoperatively. RESULTS: In 24 patients PMN respiratory burst activity was increased before operation and had decreased significantly (p < 0.01) on postoperative day 1 (high responders group). In the remaining 22 patients (low responders group) respiratory burst activity was low before operation and had increased significantly (p < 0.05) on postoperative day 1. PMN CD 11b activity followed a similar trend. Monocyte activity responded similarly (in the high group mean (SEM) MCF preoperatively was 69.14 (13.15) compared with 58.23 (10.8) on day 1, and in the low group the corresponding figures were 38.5 (7.01) and 8.43 (5.2). Expression of CD14 did not differ between the groups and was less postoperatively than preoperatively. The groups did not differ in age, sex, APACHE 11 scores, smoking habits or types of disease and there was no major infective complications in either group. CONCLUSION: There are two distinct patterns of PMN and monocyte responses to injury that are independant of age, sex and severity of operation. These may be associated with the degree of stress preoperatively or with genetic factors. PMID- 9373226 TI - Mutagenicity from neutrophils after challenge with Helicobacter pylori and bile. AB - OBJECTIVE: To study some mechanisms involved in Helicobacter pylori (H. pylori) induced gastric carcinogenesis. DESIGN: In vitro study. SETTING: Medical centre hospital, Sweden. INTERVENTIONS: Mutagenicity in Ames' test of neutrophils challenged for 2 hours or more by two different strains of H. pylori. One strain designated NCTC 11637 by the National College of Type Cultures activated neutrophils to an oxidative burst and producing vacuolating cytotoxin, the other strain C-7050 lacked these abilities. Mutagenicity was also studied with sterile human gall bladder bile alone added to neutrophils or in combination with both neutrophils and H. pylori. RESULTS: There was no increase in the number of revertants with the crude suspension or the supernatant of neutrophils challenged for 1 hour or less with H. pylori, bile, or the combination of both. However, in 5 out of 19 experiments there was significant mutagenicity after challenge of neutrophils for 2 hours or more with either strain of H. pylori, bile, or the combination of the two. The strongest mutagenicity was obtained after challenge over night (18 hours) with the combination of H. pylori and bile. CONCLUSION: Mutagenicity occurs when neutrophils are challenged with H. pylori and bile. Factors other than reactive oxygen metabolites seem to be responsible. PMID- 9373227 TI - Enteral or parenteral feeding after total gastrectomy: prospective randomised pilot study. AB - OBJECTIVE: To compare the efficacy and cost of enteral and parenteral feeding after total gastrectomy. DESIGN: Prospective randomised open study. SETTING: University hospital, Finland. SUBJECTS: 29 patients undergoing curative total gastrectomy for gastric cancer. INTERVENTIONS: 13 patients were given early enteral feeding by nasojejunal tube and 16 patients parenteral nutrition by central venous catheter. MAIN OUTCOME MEASURES: Postoperative complications, duration of hospital stay, serum CRP and albumin concentrations, cost, and postoperative abdominal symptoms. RESULTS: One patient in the enteral feeding group discontinued the study on day 1. Oesophagojejunal leaks developed in one patient in each group. Infective complications occurred in 3 (23%) in the enteral group and 5 (31%) in the parenteral group. Serum CRP concentration on day six was lower in the enteral feeding group than in the parenteral feeding group (32 (16) g/L compared with 61 (41) g/L; p = 0.02). Enteral feeding was well tolerated. Diarrhoea developed earlier in the enteral than in the parenteral group (days 3-5 compared with 5-7, respectively) but there was a tendency to an increased risk of diarrhoea in the parenteral group. Parenteral feeding was more than four times as expensive as enteral feeding. CONCLUSION: Enteral nasojejunal feeding is safe and well tolerated after total gastrectomy. It is also cheaper than parenteral nutrition. PMID- 9373228 TI - Does the index operation influence the course and outcome of adhesive intestinal obstruction? AB - OBJECTIVE: To ascertain the incidence of obstruction after various operations and find out if the index operation influenced the course and outcome of adhesive small bowel obstruction. DESIGN: Retrospective study. SETTING: Teaching hospital, Israel. SUBJECTS: 190 of 248 patients who presented with small bowel obstruction between January 1980 and December 1994. INTERVENTIONS: All patients were treated conservatively and operated on only if they did not improve or deteriorated. MAIN OUTCOME MEASURES: Incidence of obstruction depending on site of index operation, and response to treatment. RESULTS: 46 Patients (24%) had undergone upper abdominal operations, 26 (14%) small bowel resection, 47 (25%) appendicectomy, 27 (14%) gynaecological operations, and 44 (23%) colonic resections. The annual incidence of obstructive complications among the 190 patients in the groups studied was highest after appendicectomy (3.1/year) and colonic resections (2.9/year) and lowest after operations on the gallbladder and pancreas (1.1/year). Postoperative adhesive obstruction presented earlier after operations on the small bowel (median 1 year, range 5.4-20) and colon (median 1 year, range 2.2-40) than after the other operations. 60 (32%) of patients with acute small bowel obstruction had a history of abdominal malignancy, and obstruction was more likely to be complete after small bowel resection (20/26, 77%) compared with 39/74 (53%) after appendicectomy or gynaecological surgery, 17/46 (37%) after upper abdominal surgery, and 15/44 (34%) after colonic resection. Patients who developed obstruction after colonic resection had the longest period of conservative treatment (median 60 hours, range 24-216) and had the highest morbidity (8/44, 18%) although only 2 required bowel resection. Two patients died, both after obstruction following upper abdominal operations. CONCLUSIONS: Patients who present with obstruction after small bowel resection are extremely likely to be completely obstructed. Perhaps the morbidity associated with obstruction after colonic resection could be reduced if patients were operated on earlier. PMID- 9373229 TI - The effect of octreotide on wound healing: an in vitro and in vivo experimental study. AB - OBJECTIVE: To investigate the effect of octreotide on wound healing. DESIGN: Experimental studies in vitro and in rats. SETTING: Teaching hospital, Israel. MATERIAL: Cultured human diploid fetal fibroblasts, and 36 male Wistar rats. INTERVENTIONS: Octreotide was added to cultures of fibroblasts in doses of 2, 10, 30, 60 and 120 ng/ml and fibroblasts were counted after 2, 4, and 6 days. Intestinal anastomoses were made in 36 rats. Rats in the octreotide group (n = 18) were given subcutaneous injections of 0.25 microg/kg twice daily and 6 rats were killed at 3, 7, and 14 days. The control group were given injections of saline. Anastomotic bursting pressures and hydroxyproline content were measured at each of the three times. MAIN OUTCOME MEASURES: Fibroblast counts, anastomotic bursting pressures, and hydroxyproline concentrations. RESULTS: Octreotide did not inhibit fibroblast proliferation in any of the doses at any of the time periods. The anastomotic bursting pressure was slightly higher in the octreotide group at each of the time points, but not significantly so, and there was no difference in hydroxyproline content between the octreotide and control groups. Octreotide did not inhibit wound healing either in vitro or in vivo. PMID- 9373230 TI - Growth hormone increases and IGF-1 reduces the response to Escherichia coli infusion in injured pigs. AB - OBJECTIVE: To investigate if growth hormone (GH) or its main mediator insulin like growth factor-1 (IGF-1) alters the response to infusion of live Escherichia coli in injured pigs. DESIGN: Controlled experiment. SETTING: University laboratory, Norway. SUBJECTS: 30 piglets. INTERVENTIONS: The response to infusion of Escherichia coli was compared after a bolus of GH 16 IU (n = 8) or a continuous infusion of IGF-1 1.3 mg/hour (n = 8) in injured piglets. A group with trauma (surgery) and Escherichia coli infusion (n = 8) and a group with trauma only (n = 6) served as controls. MAIN OUTCOME MEASURES: Systemic and regional haemodynamics, oxygen consumption, and acid-base regulation; and circulating concentrations of catecholamines, free fatty acids (FFA), glucose, and lactate Results: After infusion of Escherichia coli, cardiac output was lower and heart rate was higher in the GH than in the IGF-1-treated group. Aortic pH was lower in the GH group compared with the septic controls, whereas aortic pH was higher in the IGF-1 group compared with the septic controls. Portal vein pH was lower in the GH group than in the other three groups. Free fatty acids and lactate concentrations were higher in the GH group than in the other three groups. Glucose concentrations were lower in the IGF-1 group than in the other three groups. Renal artery flow was higher in the IGF-1 than in the GH group and the septic controls. Circulating concentrations of dopamine was higher in the IGF-1 group than in the other three groups, whereas that of noradrenaline was higher in the GH group than in the IGF-1 group. (For all differences stated, p < 0.05). CONCLUSIONS: Acute treatment with GH increased the circulatory and metabolic response to Escherichia coli infusion, in contrast to treatment with IGF-1, which reduced the response PMID- 9373231 TI - Direct percutaneous jejunostomy. PMID- 9373232 TI - Development of chylous ascites after laparoscopic Nissen fundoplication. PMID- 9373233 TI - Contribution of the lateral anlage to the embryogenesis of the thyroid gland: evidence of a persisting thyrocarotid duct. PMID- 9373234 TI - Fifty years of studies of the biology and therapy of childhood leukemia. PMID- 9373235 TI - Evolving views of the major histocompatibility complex. PMID- 9373236 TI - Mutations in the Fas antigen in patients with multiple myeloma. AB - Programmed cell death, or apoptosis, is well documented as a physiological means of eliminating activated lymphocytes and maintaining immune homeostasis. Apoptosis has also been implicated in the targeting of tumor cells by cytotoxic T lymphocytes and natural killer cells. One of the two primary mechanisms used in cell-mediated cytotoxicity is the Fas/FasLigand system. Activated or transformed cells expressing the Fas antigen on their surface are susceptible to killing by immune effector cells that express the Fas ligand. Many neoplastic cells, including those derived from patients with multiple myeloma, express Fas antigen on their surface, but do not undergo apoptosis in response to antigen crosslinking. One possibility for the lack of Fas-mediated apoptosis includes mutations in the Fas antigen. Loss of function mutations in the Fas antigen have been associated with congenital autoimmune disease in humans, and have been defined as the genetic defect the in lpr mice. Mutations in the Fas antigen have not been previously described in cancer patients. In this study, we show that mutations occur in the Fas antigen which may cause loss of function and contribute to the pathogenesis of the neoplastic disease, multiple myeloma. Using reverse transcriptase-polymerase chain reaction (RT-PCR), single-stranded conformation polymorphism (SSCP) analysis, and DNA sequencing, we examined the cDNA structure of the Fas antigen in 54 bone marrow (BM) specimens obtained from myeloma patients. Six patient specimens (11%) did not express detectable levels of Fas antigen mRNA. Of the 48 BM specimens which did express Fas antigen, 5 (10%) displayed point mutations. All of the mutations identified were located in the cytoplasmic region of the Fas antigen known to be involved in transduction of an apoptotic signal. Two separate individuals demonstrated an identical mutation at a site previously shown to be mutated in the congenital autoimmune syndrome, ALPS. One patient exhibited a point mutation at a site only two amino acids removed from the documented lesion of the lprcg mouse. Although the functional status of these point mutations remains to be determined, we propose that Fas antigen mutations may contribute to the pathogenesis and progression of myeloma in some patients. PMID- 9373237 TI - Fusion of the platelet-derived growth factor receptor beta to a novel gene CEV14 in acute myelogenous leukemia after clonal evolution. AB - Chromosomal translocations involving band 5q31-35 occur in several hematologic disorders. A clone with a t(5; 14)(q33; q32) translocation appeared at the relapse phase in a patient with acute myelogenous leukemia who exhibited a sole chromosomal translocation, t(7; 11), at initial diagnosis. After the appearance of this clone, the leukemia progressed with marked eosinophilia, and combination chemotherapy was ineffective. Southern blot analysis showed a rearrangement of the platelet-derived growth factor receptor beta (PDGFRbeta) gene at 5q33 which was not observed at initial diagnosis. This translocation resulted in a chimeric transcript fusing the PDGFRbeta gene on 5q33 with a novel gene, CEV14, located at 14q32. Expression of the 5' region of the PDGFRbeta cDNA, upstream of the breakpoint, was not detected. However, the 3' region of PDGFRbeta, which was transcribed as part of the CEV14-PDGFRbeta fusion gene, was detected. A partial cDNA for a novel gene, CEV14, includes a leucine zipper motif and putative thyroid hormone receptor interacting domain and is expressed in a wide range of tissues. The expression of a CEV14-PDGFRbeta fusion gene in association with aggressive leukemia progression suggests that this protein has oncogenic potential. PMID- 9373238 TI - Localization of Kaposi's sarcoma-associated herpesvirus in bone marrow biopsy samples from patients with multiple myeloma. AB - We have recently demonstrated the presence of Kaposi's sarcoma-associated herpesvirus (KSHV) in cultured bone marrow (BM) stromal dendritic cells from all patients with myeloma studied. To show that these findings were not an artifact of tissue culture, we performed in situ hybridization (ISH) and polymerase chain reaction (PCR) to detect KSHV in BM core biopsies. Using ISH to open reading frame-72 (ORF 72), we localized KSHV to BM dendritic cells in 17 of 20 patients with myeloma, 2 patients with plasmacytosis associated with the acquired immunodeficiency syndrome, and 1 case of aplastic anemia. In contrast, BM from normal subjects (n = 4) and patients with lymphoma and leukemia (n = 21) did not contain KSHV. PCR amplification with KSHV primers demonstrated product in fresh BM biopsy samples from 6 of 7 myeloma patients, whereas three normal marrows contained no amplified product. These findings suggest that KSHV, possibly through alterations in the BM microenvironment and production of viral interleukin-6 (vIL-6), may stimulate and maintain abnormal plasma cell proliferation in myeloma and related disorders. PMID- 9373239 TI - Comparison of caspase activation and subcellular localization in HL-60 and K562 cells undergoing etoposide-induced apoptosis. AB - Previous studies have shown that K562 chronic myelogenous leukemia cells are resistant to induction of apoptosis by a variety of agents, including the topoisomerase II (topo II) poison etoposide, when examined 4 to 24 hours after treatment with an initiating stimulus. In the present study, the responses of K562 cells and apoptosis-proficient HL-60 acute myelomonocytic leukemia cells to etoposide were compared, with particular emphasis on determining the long-term fate of the cells. When cells were treated with varying concentrations of etoposide for 1 hour and subsequently plated in soft agar, the two cell lines displayed similar sensitivities, with a 90% reduction in colony formation at 5 to 10 mu mol/L etoposide. After treatment with 17 mu mol/L etoposide for 1 hour, cleavage of the caspase substrate poly(ADP-ribose) polymerase (PARP), DNA fragmentation, and apoptotic morphological changes were evident in HL-60 cells in less than 6 hours. After the same treatment, K562 cells arrested in G2 phase of the cell cycle but otherwise appeared normal for 3 to 4 days before developing similar apoptotic changes. When the etoposide dose was increased to 68 mu mol/L, apoptotic changes were evident in HL-60 cells after 2 to 3 hours, whereas the same changes were observed in K562 cells after 24 to 48 hours. This delay in the development of apoptotic changes in K562 cells was accompanied by delayed release of cytochrome c to the cytosol and delayed appearance of peptidase activity that cleaved the fluorogenic substrates Asp-Glu-Val-Asp-aminotrifluoromethylcoumarin (DEVD-AFC) and Val-Glu-Ile-Asp-aminomethylcoumarin (VEID-AMC) as well as an altered spectrum of active caspases that were affinity labeled with N-(Nalpha benzyloxycarbonylglutamyl-Nepsilon-biotin yllysyl) aspartic acid [(2,6 dimethylbenzoyl)oxy]methyl ketone [z-EK(bio)D-aomk]. On the other hand, the activation of caspase-3 under cell-free conditions occurred with indistinguishable kinetics in cytosol prepared from the two cell lines. Collectively, these results suggest that a delay in the signaling cascade upstream of cytochrome c release and caspase activation leads to a long latent period before the active phase of apoptosis is initiated in etoposide-treated K562 cells. Once the active phase of apoptosis is initiated, the spectrum and subcellular distribution of active caspase species differ between HL-60 and K562 cells, but a similar proportion of cells are ultimately killed in both cell lines. PMID- 9373240 TI - In vivo expression of B7-1 and B7-2 by follicular lymphoma cells can prevent induction of T-cell anergy but is insufficient to induce significant T-cell proliferation. AB - Expression of B7 family costimulatory molecules on B cells defines their capacity to function as antigen presenting cells (APCs). B cells that do not express B7 costimulatory molecules induce T-cell tolerance. Therefore, the expression of B7 costimulatory molecules on malignant B cells might be critical for their recognition by anti-tumor-specific T cells. Here we show that virtually all germinal center (GC)-derived B-cell lymphomas including follicular lymphoma (FL) and diffuse large cell lymphoma, but not mantle cell lymphoma or small lymphocytic lymphomas (SLL/CLL), express B7-1 (CD80) and B7-2 (CD86) on their cell surface in situ, although at extremely low levels. Despite their expression of low levels of B7-1 and B7-2, FL cells could not induce significant allogeneic T-cell proliferation. However, B7 costimulatory molecules on FL appeared to be functional because they were capable of increasing T-cell proliferation of preactivated T cells in a secondary allogeneic mixed lymphocyte response. Moreover, low B7 expression was sufficient to prevent the induction of alloantigen-specific anergy in vitro. Therefore, we postulate that whereas low level expression of B7 is not sufficient to initiate a productive antilymphoma T cell response, it might be sufficient to prevent T-cell tolerance in vivo. PMID- 9373241 TI - The novel cyclin-dependent kinase inhibitor flavopiridol downregulates Bcl-2 and induces growth arrest and apoptosis in chronic B-cell leukemia lines. AB - Flavopiridol is a novel, potent inhibitor of cyclin-dependent kinases (CDK). This synthetic flavone has been reported to exhibit antitumor activity in murine and human tumor cell lines in vitro and in vivo and is currently undergoing clinical phase I evaluation. In the present study, 1 Epstein-Barr virus (EBV)-transformed B-prolymphocytic cell line (JVM-2), 1 EBV-transformed B-CLL cell line (I83CLL), and 1 non-EBV transformed B-CLL cell line (WSU-CLL) were used as targets. Treatment of the cells with flavopiridol (100 nmol/L to 400 nmol/L) led to a marked dose- and time-dependent inhibition of cell growth and survival as determined using trypan blue exclusion. Morphologic analysis showed characteristic apoptotic changes such as chromatin condensation and fragmentation, membrane blebbing, and formation of apoptotic bodies. Furthermore, quantitative assessment of apoptosis-associated DNA strand breaks by in situ TdT labeling showed that a significant number of flavopiridol-treated cells underwent apoptosis. These cellular effects were associated with a significant decrease in bcl-2 expression as observed by Northern and Western blotting. The results showed that flavopiridol downregulates bcl-2 mRNA and bcl-2 protein expression within 24 hours. Genistein and quercetin, two flavonoids that do not inhibit CDKs, did not affect bcl-2 expression. These data suggest an additional mechanism of action of this new flavone which might be useful as an agent in the treatment of chronic lymphoid malignancies. PMID- 9373242 TI - A prospective randomized trial of buffy coat versus CD34-selected autologous bone marrow support in high-risk breast cancer patients receiving high-dose chemotherapy. AB - High-dose chemotherapy with hematopoietic progenitor cell support is administered increasingly to selected categories of patients with high-risk malignancies. Bone marrow and/or peripheral blood progenitor cells (PBPCs) are commonly cryopreserved with the cryoprotectant dimethyl sulfoxide (DMSO), which can cause a variety of systemic side effects when the graft is thawed and infused. The progenitor cells thought to be responsible for hematopoietic recovery express the CD34 antigen and constitute 1% to 3% of the marrow cells and 0.5% of the PBPC fraction. Transplantation of a CD34(+) graft would markedly reduce the volume and thus the amount of DMSO required, thereby decreasing the infusion-related toxicities. In this study, 89 high-risk breast cancer patients received high-dose therapy and were randomized to receive an autologous CD34(+) marrow graft (Arm A) versus a standard buffy coat fraction (Arm B). After marrow infusion, significant increases in diastolic and systolic blood pressure, as well as significant decreases in heart rate, were documented in Arm B compared to Arm A patients (P < .001). None of the patients in Arm A experienced any clinically serious adverse events associated with the marrow infusion compared to 6% of the Arm B patients. The median time to neutrophil engraftment was 13 days for Arm A and 11 days for Arm B patients (P = .218). The median time to platelet engraftment was 27 days for Arm A and 20 days for Arm B patients (0.051). There were no other significant differences between the two arms of the study with respect to thrombocytopenia related complications or immune function reconstitution. Additionally, patients on Arm A who received >/=1.2 x 10(6) CD34(+) cells/kg had no delay in platelet recovery (22 days), compared to patients on Arm B, who also received greater than 1.2 x 10(6) CD34(+) cells/kg (20 days) (P = .604). In conclusion, this prospective randomized study demonstrates that breast cancer patients who receive high-dose therapy with autologous CD34(+) marrow support have reduced marrow infusion-related toxicity, comparable time to neutrophil engraftment and immune function recovery posttransplant, and for those who receive <1.2 x 10(6) CD34(+) cells/kg, comparable time to platelet engraftment compared to women who receive buffy coat fractions of marrow. PMID- 9373243 TI - Bidirectional effect of interleukin-10 on early murine B-cell development: stimulation of flt3-ligand plus interleukin-7-dependent generation of CD19(-) ProB cells from uncommitted bone marrow progenitor cells and growth inhibition of CD19(+) ProB cells. AB - B-cell commitment and early development from multipotent hematopoietic progenitor cells has until recently been considered to be dependent on direct interaction with stromal cells. We recently showed that the flt3 ligand (FL) has a unique ability to interact with interleukin-7 (IL-7) to directly and selectively promote B-cell development from murine bone marrow progenitor cells with a combined myeloid and lymphoid potential. Here we report that whereas IL-10 alone has no ability to stimulate growth of primitive (Lin-Sca-1(+)c-kit+) bone marrow progenitor cells, it potently enhances FL + IL-7-induced proliferation (sevenfold). This enhanced proliferation results from recruitment of progenitors unresponsive to FL + IL-7 alone, as well as from increased growth of individual clones, resulting in a 7,000-fold cellular expansion over 12 days. Single cell cultures and delayed addition studies suggested that the stimulatory effect of IL 10 was directly mediated on the progenitor cells. The cells generated in response to FL + IL-7 + IL-10 appeared to be almost exclusively proB cells, as shown by their expression of B220, CD24, CD43, and lack of expression of c mu, myeloid, erythroid, and T-cell surface antigens. Although IL-10 also enhanced kit ligand (KL) + IL-7-induced proliferation of Lin-Sca-1(+)c-kit+ progenitor cells, the resulting cells were predominantly myeloid progeny. Accordingly, FL + IL-7 + IL 10 was 100-fold more efficient in stimulating production of proB cells than KL + IL-7 + IL-10. In contrast to its ability to stimulate the earliest phase of proB cell formation and proliferation, IL-10 inhibited growth of proB cells generated in response to FL + IL-7. Analysis of CD19 expression on cells generated in FL + IL-7 + IL-10 showed that almost all cells generated under these conditions lacked expression of CD19, in contrast to cells generated in the absence of IL-10, which were predominantly CD19(+). Replating of sorted CD19(+) and CD19(-) proB cells in FL + IL-7 or FL + IL-7 + IL-10 showed that IL-10 efficiently blocked growth of CD19(+), but not CD19(-) cells. Both CD19(-) and CD19(+) cells expressed lambda5 and VpreB , shown to be specific for B-cell progenitors. In addition, sorted CD19(-) cells generated CD19(+) cells in response to FL + IL-7. Thus, IL-10 has a dual regulatory effect on early B-cell development from primitive murine bone marrow progenitor cells in that it enhances FL + IL-7-induced proB-cell formation and growth before acquisition of CD19 expression, whereas growth of CD19(+) proB cells is inhibited. PMID- 9373244 TI - Predominant expression of murine Bmx tyrosine kinase in the granulo-monocytic lineage. AB - In the course of systematic cloning of protein tyrosine kinases (PTKs) expressed in hematopoietic stem and progenitor cells, we have identified the murine homologue of human Bmx. It encodes a protein containing the five domains characteristic of the Tec family of cytoplasmic src-related PTKs: pleckstrin homology (PH), Tec homology (TH), src homology 3 and 2 (SH3 and SH2), and tyrosine kinase (TK). In adults, Bmx expression was found primarily in bone marrow and at a lower level in lung and heart. During fetal development it was also found in the spleen at late stage of gestation and in neonates. Analysis of bone marrow subpopulations showed that Bmx was expressed in the progenitor cell population and maturing hematopoietic cells of the granulo/monocytic lineage where expression increased with maturation and differentiation. At the periphery, a high level of Bmx expression was also found in neutrophils and monocytes/macrophages. Bmx expression was not detected in the primitive hematopoietic stem cell population, and cells of the B-, T-, and erythroid lineages. It was also not detected in most of the cell lines examined. Our results indicate that Bmx is another member of the Btk/Itk/Tec PTK family, which is predominantly expressed in the granulo-monocytic lineage within the hematopoietic system. PMID- 9373245 TI - The Bmx tyrosine kinase induces activation of the Stat signaling pathway, which is specifically inhibited by protein kinase Cdelta. AB - Members of the hematopoietically expressed Tec tyrosine kinase family have an important role in hematopoietic signal transduction, as exemplified by the crucial role of Btk for B-cell differentiation and activation. Although a variety of cell surface receptors have been found to activate Tec tyrosine kinases, the specific signaling pathways and substrate molecules used by Tec kinases are still largely unknown. In this study a Tec family kinase, Bmx, was found to induce activation of the Stat signaling pathway. Bmx induced the tyrosine phosphorylation and DNA binding activity of all the Stat factors tested, including Stat1, Stat3, and Stat5, both in mammalian and insect cells. Bmx also induced transcriptional activation of Stat1- and Stat5-dependent reporter genes. Other cytoplasmic tyrosine kinases, Syk, Fyn, and c-Src, showed no or only weak ability to activate Stat proteins. Expression of Bmx in mammalian cells was found to induce activation of endogenous Stat proteins without activation of endogenous Jak kinases. We further analyzed the Bmx-mediated activation of Stat1, which was found to be regulated by protein kinase C delta (PKCdelta) isoform, but not beta 1, epsilon, or zeta isoforms, leading to inhibition of Stat1 tyrosine phosphorylation. In conclusion, these studies show that Bmx, a Tec family kinase, can function as an activator of the Stat signaling pathway and identify a role for PKCdelta in the regulation of Bmx signaling. PMID- 9373246 TI - Hydroxyurea can be used to increase mouse c-kit+Thy-1. 1(lo)Lin-/loSca-1(+) hematopoietic cell number and frequency in cell cycle in vivo. AB - The DNA synthesis inhibitor hydroxyurea (HU) was administered to determine whether it induces changes in the cell-cycle status of primitive hematopoietic stem cells (HSCs)/progenitors. Administration of HU to mice leads to bone marrow accumulation of c-kit+Thy-1.1(lo)Lin-/loSca-1(+) (KTLS) cells in S/G2/M phases of the cell cycle. HU is a relatively nontoxic, reversible cell-cycle agent that can lead to approximately a threefold expansion of KTLS cells in vivo and approximately an eightfold increase in the number of KTLS cells in S/G2/M. HSCs in HU-treated mice have undiminished multilineage long-term and short-term clonal reconstitution activity. PMID- 9373247 TI - Synergistic action of Flt3 and gp130 signalings in human hematopoiesis. AB - We recently showed that c-kit signal synergizes with glycoprotein (gp)130 signal mediated by a complex of interleukin (IL)-6 and soluble IL-6 receptor (IL-6/sIL 6R) to stimulate the expansion of human primitive hematopoietic progenitor cells and erythropoietin-independent erythropoiesis. In the present study, we examined the effect of a ligand for Flt3 (FL), whose receptor tyrosine kinase is closely related to c-kit, in combination with IL-6/sIL-6R on human hematopoiesis in vitro. In serum-containing methylcellulose clonal culture of cord blood CD34(+) cells, whereas FL alone stimulated only granulocyte-macrophage (GM) colony formation, erythroid bursts and mixed colonies in addition to GM colonies were induced by FL with IL-6/sIL-6R, but not IL-6/sIL-6R alone. In suspension culture, CD34(+) cells generated a small number of myeloid cells in the presence of FL or IL-6/sIL-6R alone. However, the addition of IL-6/sIL-6R to the culture with FL induced the generation of a significant number of erythroid cells and megakaryocytes in addition to myeloid cells. The combination of FL and IL-6/sIL 6R also induced a remarkable expansion of GM colony- and erythroid burst-forming cells and multipotential progenitors, although FL or IL-6/sIL-6R alone induced the generation of only a small number of progenitors for GM colonies. The synergistic effects of FL and IL-6/sIL-6R were confirmed in serum-free clonal and suspension cultures. In addition, the addition of anti-human gp130 monoclonal antibodies abrogated the synergistic action. These results indicate that Flt3 signal, as well as c-kit signal, synergizes with gp130 signal to stimulate human myelopoiesis, erythropoiesis and megakaryopoiesis, and the expansion of primitive multipotential hematopoietic progenitor cells. PMID- 9373248 TI - High thrombopoietin production by hematopoietic cells induces a fatal myeloproliferative syndrome in mice. AB - To evaluate the effects of long-term, high-dose exposure to thrombopoietin (TPO), lethally irradiated mice were grafted with bone marrow cells infected with a retrovirus carrying the murine TPO cDNA. Mice were studied for 10 months after transplantation. In plasma, TPO levels were highly elevated (10(4) U/mL) throughout the course of the study. All mice developed a lethal myeloproliferative disorder evolving in two successive phases. During the first phase (7-9 weeks posttransplant), platelet and white blood cell (WBC) counts rose four- and ten-fold, respectively, whereas hematocrits decreased slightly to 29% +/- 3%. The WBC were mainly mature granulocytes, but myeloid precursor cells were invariably observed as well as giant platelets with an irregular granule distribution. The striking features were a massive hyperplasia of megakaryocytes and granulocytes in the spleen and bone marrow and a hypoplasia of erythroblasts in bone marrow. Total numbers of megakaryocyte colony-forming cell, burst-forming unit-erythroid, and granulocyte macrophage colony-forming cells were increased but colony-forming unit-erythroid numbers decreased. From 10 weeks posttransplant and thereafter, WBC, platelets, and red blood cell numbers declined dramatically. The absolute numbers of progenitor cells were very low in the spleen and bone marrow, but sharply increased in the blood and peritoneal cavity. Extramedullary hematopoiesis was observed in several organs. Histologic sections of the spleen and bones revealed severe fibrosis and osteosclerosis. The mean survival time was 7 months posttransplant and mice died with severe pancytopenia. Notably, two mice died between 3 and 4 months posttransplant with a leukemic transformation. This disorder was transplantable into secondary recipients who developed an attenuated form of the disease similar to the one previously described (Yan et al, Blood 86:4025, 1995). Taken together, our data show that high and persistent TPO production by transduced hematopoietic cells in mice results in a fatal myeloproliferative disorder that has a number of features in common with human idiopathic myelofibrosis. PMID- 9373251 TI - Recombinant soluble interleukin-11 (IL-11) receptor alpha-chain can act as an IL 11 antagonist. AB - We have expressed a soluble N-glycosylated form of the murine interleukin-11 (IL 11) receptor alpha-chain (sIL-11R) and examined signaling in cells expressing the gp130 molecule. In the presence of gp130 but not the transmembrane IL-11R, the sIL-11R mediated IL-11-dependent differentiation of M1 leukemic cells and proliferation in Ba/F3 cells. Early intracellular events stimulated by the sIL 11R including phosphorylation of gp130, STAT 3, and SHP-2 were similar to signaling through the transmembrane IL-11R. IL-11 bound to sIL-11R with low affinity (kd 10 to 50 nmol/L). Binding of sIL-11R to gp130 was IL-11 dependent with intermediate affinity (kd 1.5 to 3.0 nmol/L). However, the concentration of IL-11 required for signaling through the sIL-11R was 10- to 20-fold greater than that required for cells expressing the transmembrane IL-11R and gp130 in the absence of sIL-11R. Furthermore, the sIL-11R was capable of antagonizing the activity of IL-11 when tested on cells expressing the transmembrane IL-11R and gp130. We propose that the observed IL-11 antagonism by the sIL-11R may depend on limiting numbers of gp130 molecules on cells already expressing the transmembrane IL-11R. PMID- 9373250 TI - Thrombopoietin upregulates the promoter conformation of p53 in a proliferation independent manner coincident with a decreased expression of Bax: potential mechanisms for survival enhancing effects. AB - Thrombopoietin (Tpo) has proliferative and maturational effects on immature and more committed cells, respectively. We previously reported a role for Tpo as a survival factor in the factor-dependent human cell line M07e by demonstrating that Tpo suppresses apoptosis in the absence of induced proliferation. Wild-type p53 is a tumor suppressor gene that can play a vital role in mediating growth factor withdrawal-induced apoptosis in factor-dependent hematopoietic cells. Wild type p53 can switch from a suppressor conformation, with an antiproliferative, pro-apoptotic phenotype, to a promoter conformation that has a diminished ability to mediate cell cycle arrest and apoptosis. In an effort to elucidate the mechanisms through which Tpo suppresses apoptosis, we investigated the effects of Tpo treatment on p53-mediated apoptosis in M07e cells. Tpo upregulated the expression of the promoter conformation of p53 in M07e cells coincident with a downregulation of Bax and Mdm2 protein levels. Protein levels of Bcl-2 and Bcl-xL did not significantly vary as a function of growth-factor stimulation. Conversely, the levels of suppressor conformation p53 were maximal when M07e was in a growth arrested state and decreased during factor stimulation. Furthermore, Tpo treatment induced an extranuclear buildup and greatly weakened the DNA binding capacity of p53. p53-specific antisense oligonucleotide treatment recapitulated the effects of Tpo treatment on the levels of Bax, Mdm-2, and Bcl 2. These results suggest that Tpo is suppressing growth factor withdrawal induced apoptosis, at least in part, by downregulating the expression of pro-apoptotic Bax protein levels, through modulating the conformation of p53, which results in a functional inactivation of its pro-apoptotic abilities. PMID- 9373249 TI - Functional heterogeneity of human CD34(+) cells isolated in subcompartments of the G0 /G1 phase of the cell cycle. AB - Using simultaneous Hoechst 33342 (Hst) and Pyronin Y (PY) staining for determination of DNA and RNA content, respectively, human CD34(+) cells were isolated in subcompartments of the G0 /G1 phase of the cell cycle by flow cytometric cell sorting. In both bone marrow (BM) and mobilized peripheral blood (MPB) CD34(+) cells, primitive long-term hematopoietic culture-initiating cell (LTHC-IC) activity was higher in CD34(+) cells isolated in G0 (G0CD34(+) cells) than in those residing in G1 (G1CD34(+) cells). However, as MPB CD34(+) cells displayed a more homogeneous cell-cycle status within the G0 /G1 phase and a relative absence of cells in late G1 , DNA/RNA fractionation was less effective in segregating LTHC-IC in MPB than in BM. BM CD34(+) cells belonging to four subcompartments of increasing RNA content within the G0 /G1 phase were evaluated in functional assays. The persistence of CD34 expression in suspension culture was inversely correlated with the initial RNA content of test cells. Multipotential progenitors were present in G0 or early G1 subcompartments, while lineage-restricted granulomonocytic progenitors were more abundant in late G1 . In vitro hematopoiesis was maintained for up to 6 weeks with G0CD34(+) cells, whereas production of clonogenic progenitors was more limited in cultures initiated with G1CD34(+) cells. To test the hypothesis that primitive LTHC-ICs would reenter a state of relative quiescence after in vitro division, BM CD34(+) cells proliferating in ex vivo cultures were identified from their quiescent counterparts by a relative loss of membrane intercalating dye PKH2, and were further fractionated with Hst and PY. The same functional hierarchy was documented within the PKH2(dim) population whereby LTHC-IC frequency was higher for CD34(+) cells reselected in G0 after in vitro division than for CD34(+) cells reisolated in G1 or in S/G2 + M. However, the highest LTHC-IC frequency was found in quiescent PKH2(bright) CD34(+) cells. Together, these results support the concept that cells with distinct hematopoietic capabilities follow different pathways during the G0 /G1 phase of the cell cycle both in vivo and during ex vivo culture. PMID- 9373252 TI - Analysis of the involvement of the von Willebrand factor-glycoprotein Ib interaction in platelet adhesion to a collagen-coated surface under flow conditions. AB - The requisite initial reaction for in vivo thrombus formation in flowing blood is platelet adhesion to the exposed surface of the extracellular matrix. The contribution of von Willebrand factor (vWF ) in plasma and glycoprotein (GP) Ib on the platelet membrane to platelet adhesion has been well-documented. We have recently developed a procedure (the "flow adhesion assay") for measuring platelet adhesion under flow conditions that allowed us to characterize platelet adhesion to a collagen-coated surface. Here, we apply our method to analyze platelet adhesion to a vWF-coated surface to determine how this might differ from adhesion to a collagen-coated surface. Platelet adhesion to the vWF-coated surface was monitored as the linear increase in the area occupied by adherent platelets. The fluorescence image showed that platelets adhering to the vWF surface were mainly single platelets, and if any were present, the platelet aggregates were small, this being the primary difference from the adhesion to a collagen surface, where adherent platelets were mostly in aggregates. The flow adhesion assay detected the movement of platelets on the vWF surface, suggesting the reversible binding of vWF with platelets. The velocity of the platelets increased at higher shear rates or at lower vWF densities on the surface. Treatment of the vWF-coated surface with the aggregating agent botrocetin before initiation of blood flow increased platelet adhesion while dramatically decreasing the velocity of platelet movement. The present observations on the adhesion of platelets to the vWF-pretreated collagen surface and measurements of the velocity of platelets moving on the collagen surface suggest that the first interaction on the collagen coated surface is the binding of vWF molecules to the collagen surface. This small number of vWF molecules would serve to attract and slow platelets flowing near the surface. This would facilitate the actual adhesion to the collagen surface that is mainly generated by the interaction between platelet collagen receptors, including GP Ia/IIa and GP VI, with collagen. PMID- 9373253 TI - Activation of human platelets by the membrane-expressed A1 domain of von Willebrand factor. AB - Platelet activation and microthrombus formation are invariable features of xenograft rejection and the vascular injury observed when porcine organs are transplanted into primates. This pathological process could be mediated, at least in part, by aberrant interactions of von Willebrand Factor (vWF) associated with the donor vasculature with host platelets. Unlike human vWF, native porcine vWF (pvWF) interacts with human GPIb independently of shear stress or nonphysiological stimuli, eg, ristocetin. We therefore contrasted the potential of isolated human and porcine vWF-A1-domains to interact with human platelets in vitro. Both human and porcine vWF-A1-domains expressed as glycosyl phosphatidylinositol-linked FLAG fusion proteins on COS-7 cells induced GPIb dependent aggregation and intracellular Ca++ uptake of platelets, independent of both the remainder of the vWF protein and additional modifying factors. Porcine A1-domains were more potent than human homologues, and in addition ristocetin could boost platelet aggregation only with the human A1-domain. Putative conformational changes in the porcine A1-domain could result in the heightened, ristocetin-independent interactions observed with human platelets and may be of importance for xenograft survival. PMID- 9373254 TI - The c-kit ligand stem cell factor and anti-IgE promote expression of monocyte chemoattractant protein-1 in human lung mast cells. AB - Recent data suggest that mast cells (MC) are involved in the regulation of leukocyte accumulation in inflammatory reactions. In this study, expression of leukocyte-chemotactic peptides (chemokines) in purified human lung MC (n = 16) and a human mast cell line, HMC-1, was analyzed. Northern blotting and reverse transcriptase-polymerase chain reaction (RT-PCR) showed baseline expression of monocyte chemoattractant protein (MCP)-1 mRNA in unstimulated MC. Exposure of MC to recombinant stem cell factor (rhSCF, 100 ng/mL) or anti-IgE (10 microgram/mL) was followed by a substantial increase in expression of MCP-1 mRNA. Neither unstimulated nor stem cell factor (SCF )-stimulated lung MC expressed transcripts for interleukin-8 (IL-8), macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, or RANTES by Northern blotting. The mast cell line HMC-1, which contains a mutated and intrinsically activated SCF-receptor, was found to express high levels of MCP-1 mRNA in a constitutive manner. Exposure of HMC-1 cells to rhSCF resulted in upregulation of MCP-1 mRNA expression, and de novo expression of MIP-1beta mRNA. The SCF-induced upregulation of MCP-1 mRNA in lung MC and HMC 1 was accompanied by an increase in immunologically detectable MCP-1 in cell supernatants (sup) (lung MC [<98%], control medium, 1 hour: 159 +/- 27 v SCF, 100 ng/mL, 1 hour: 398 +/- 46 pg/mL/10(6) cells; HMC-1: control, 1 hour: 894 +/- 116 v SCF, 1 hour: 1,536 +/- 265 pg/mL/10(6)). IgE-dependent activation was also followed by MCP-1 release from MC. MC-sup and HMC-1-sup induced chemotaxis in blood monocytes (Mo) (control: 100% +/- 12% v 2-hour-MC-sup: 463% +/- 38% v HMC-1 sup: 532% +/- 12%), and a monoclonal antibody (MoAb) to MCP-1 (but not MoAb to IL 8) inhibited Mo-chemotaxis induced by MC-sup or HMC-1-sup (39% to 55% inhibition, P < .05). In summary, our study identifies MCP-1 as the predominant CC-chemokine produced and released in human lung MC. MCP-1 may be a crucial mediator in inflammatory reactions associated with MC activation and accumulation of MCP-1 responsive leukocytes. PMID- 9373255 TI - Neoexpression of the c-met/hepatocyte growth factor-scatter factor receptor gene in activated monocytes. AB - Hepatocyte growth factor-scatter factor (HGF-SF ) mediates mito-, moto-, and morphogenic effects through the MET receptor, a membrane bound tyrosine kinase. HGF-SF/MET signaling is mitogenic for a large number of epithelial and endothelial cells and activates organ regeneration. HGF-SF transcripts have been detected in various myeloid cell lines. Therefore, the potential role of HGF SF/MET signaling for circulating cells of the immune system, especially under conditions of inflammation, was evaluated. Several B-lymphoid and myeloid cell lines were found to express HGF-SF or c-met transcripts, while activity of both genes was mutually exclusive with the exception of low level coexpression in two B-cell lines. HGF-SF transcripts were present in low quantities in freshly isolated peripheral blood mononuclear cells (PBMNCs). In contrast, c-met expression was not detected in freshly isolated cells from peripheral blood, but was induced in monocytes by activation of monocytic or T-cell function. HGF-SF incubation led to an increased c-fos steady state transcript level in myeloblastic K562 cells and moderately promoted cell viability of freshly isolated preactivated monocytes. c-met expression is thus established in activated monocytes, in particular under conditions resembling inflammation, making these cells accessible to functional effects of HGF-SF. PMID- 9373256 TI - E- and P-selectin are not involved in the recruitment of inflammatory cells across the blood-brain barrier in experimental autoimmune encephalomyelitis. AB - In experimental autoimmune encephalomyelitis (EAE) inflammatory cells cross the endothelial blood-brain barrier (BBB) and gain access to the central nervous system (CNS). Here we show that E- and P-selectin are not involved in the recruitment of inflammatory cells across the BBB. Neither expression of E- nor P selectin is induced in BBB-forming endothelium at any time after initiation of EAE. Some of the inflammatory cells present in the CNS during EAE express ligands for E- or P-selectin. However, anti-E- and P-selectin antibodies influence neither immigration of inflammatory cells across the BBB nor the development of EAE. In general, suppression of E- and P-selectin expression on BBB endothelium is dependent on factors derived from the CNS microenvironment, eg, astrocytes. Our results suggest that during EAE suppression of E- and P-selectin expression on the BBB provides a CNS-specific mechanism to reduce leukocyte recruitment into the CNS. PMID- 9373257 TI - Protective effect of a single interleukin-12 (IL-12) predose against the toxicity of subsequent chronic IL-12 in mice: role of cytokines and glucocorticoids. AB - The mechanisms of interleukin-12 (IL-12) toxicity were studied in mice using a schedule (murine rIL-12, 400 ng/mouse, intraperitoneally [IP] once daily for 5 days) that markedly reduced body weight and food intake. On day 5, IL-12-treated mice had elevated serum and spleen IFN-gamma and tumor necrosis factor (TNF). Serum sTNFR-P75 and corticosterone (CS) were also elevated. IL-12 toxicity was partially prevented by anti-IFN-gamma antibodies or dexamethasone (DEX). A pre dose of IL-12 (200 ng/mouse on day -14) completely prevented the toxicity of subsequent IL-12. The IL-12 predose also inhibited IL-12-induced IFN-gamma levels, but did not modify IL-12-induced CS, TNF or sTNFR-P75. A protective effect was observed with a predose of lipopolysaccharide (LPS) or murine recombinant (r)IL-10. The protective effect of the IL-12 predose was reduced by coadministration of anti-IFN-gamma, but a predose of murine rIFN-gamma was not protective, suggesting that IFN-gamma is necessary but not sufficient for the protective effect of IL-12. The IL-12 predose specifically protected against IL 12 toxicity and did not modify LPS toxicity. These data indicate that IL-12 can induce tolerance to its own toxicity, probably through a downregulation of IL-12 induced IFN-gamma but independently of endogenous glucocorticoids. IFN-gamma, and possibly IL-10, might be important in this tolerance. PMID- 9373258 TI - Methylation of the Epstein-Barr virus genome in normal lymphocytes. AB - Epstein-Barr virus (EBV) latent infection in B cells persists over years or decades despite a sustained cytotoxic immune response to viral antigens. We present data that methylated EBV DNA can be detected in the normal lymphocytes of healthy volunteers. Whereas methylation of foreign DNA has been recognized as a potential cellular defense mechanism, methylation of EBV DNA may be an essential part of the virus life cycle in vivo, explaining the persistence of virus infected B cells in the face of immune surveillance. Methylation of the C promoter helps to prevent expression of the immunodominant antigens expressed from this promoter. First recognized in tumors, methylation-associated evasion of immune surveillance is not an aberration restricted to tumor tissue but is detected in normal EBV-infected lymphocytes. Methylation of the viral genome in latency also provides an explanation for the CpG suppression associated with EBV but not other large DNA viruses. PMID- 9373260 TI - Recombinant tumor necrosis factor enhances the locomotion of memory and naive B lymphocytes from human tonsils through the selective engagement of the type II receptor. AB - Recent studies performed in mice knocked out for the tumor necrosis factor (TNF ), the lymphotoxin-alpha, or the type I TNF receptor (R), genes have shown that these animals display gross defects in germinal center (GC) formation, suggesting that members of the TNF and TNFR superfamilies are involved in the control of B cell migration. Based on these premises, we have here investigated the effects of human recombinant (r) TNF on the polarization and locomotion of tonsillar B cells. rTNF increased the spontaneous polarization and locomotion of unfractionated tonsillar B lymphocytes in a dose-dependent manner by inducing a true chemotactic response. Memory (IgD-, CD38(-)) and naive (IgD+, CD38(-)), but not GC (IgD-, CD38(+)) B cells purified from total tonsillar B lymphocytes, showed a significantly higher locomotion in the presence than in the absence of rTNF. Accordingly, type I and II TNF receptors (TNFRs) were detected by flow cytometry on the surface of memory and naive, but not GC, B lymphocytes. Blocking experiments with monoclonal antibodies to type I or II TNFR showed that rTNF enhanced the spontaneous chemotaxis of memory and naive B cells through the selective engagement of type II TNFR. Finally, the TNF gene was found to be expressed in memory, naive and GC B lymphocytes; the cytokine was released in culture supernatants from the three B-cell subsets after stimulation. These data may support the hypothesis that human TNF is involved in the paracrine and perhaps autocrine control of B-cell migration in secondary lymphoid tissues. PMID- 9373259 TI - FcalphaRI (CD89) as a novel trigger molecule for bispecific antibody therapy. AB - Promising results from clinical trials with unconjugated antibodies stimulated renewed interest in immune effector mechanisms of monoclonal antibodies (MoAbs). We investigated the potential of IgA as antibody isotype for cell- or complement mediated tumor cell lysis and assessed the potential of its myeloid Fc receptor, FcalphaRI (CD89), as trigger molecule for bispecific antibody (BsAb)-mediated immunotherapy. Comparing hapten-directed antibodies of human IgA2 with IgG1 or IgG3 isotypes, we found all three to mediate effective killing of sensitized tumor target cells in whole blood assays. Analysis of effector mechanisms showed IgG-mediated lysis to be predominantly complement-dependent, whereas IgA dependent killing was primarily effector cell-mediated. A comparison of effector cell populations in antibody-dependent cell-mediated cytotoxicity (ADCC) showed neutrophils to be most important for IgA-dependent tumor cell killing, involving FcalphaRI as shown with Fc receptor blocking antibodies. Reverse ADCC experiments against target cells sensitized with Fc receptor antibodies, or assays with FcalphaRI-directed bispecific antibodies confirmed FcalphaRI as effective trigger molecule in polymorphonuclear neutrophil (PMN)-mediated lysis. During granulocyte colony-stimulating factor (G-CSF ) therapy, (FcalphaRI x HER-2/neu) bispecific antibodies induced enhanced killing of HER-2/neu positive SK-BR-3 breast cancer cells in whole blood assays. This enhanced cytotoxicity was paralleled by increased PMN counts, which lead to higher effector to target cell ratios in G CSF-primed blood. Furthermore, bispecific antibodies, directed to FcalphaRI and Candida albicans, enhanced neutrophils' phagocytosis of fungi. In summary, these results identify IgA as an effective antibody isotype for immunotherapy, working primarily via FcalphaRI on neutrophils. They suggest FcalphaRI-directed bispecific antibodies and G-CSF to be an attractive combination for malignant or infectious diseases. PMID- 9373261 TI - Human Herpesvirus 7 induces CD4(+) T-cell death by two distinct mechanisms: necrotic lysis in productively infected cells and apoptosis in uninfected or nonproductively infected cells. AB - We have investigated the cytopathic effects induced by the T-lymphotropic human herpesvirus 7 (HHV-7) on the CD4(+) T-lymphoblastoid SupT1 cell line and primary CD4(+) T lymphocytes. Acute in vitro HHV-7 infection induced (1) the formation of giant multinucleated syncytia, which eventually underwent necrotic lysis, and (2) single-cell apoptosis. Both cytopathic effects increased with the progression of infection and were blocked by phosphonoformic acid, a specific inhibitor of herpetic DNA polymerase. Using electron microscopy analysis of various samples, we found that all syncytia contained large amounts of virions and that most of them exhibited clear evidence of necrosis, whereas apoptosis was predominantly observed in single cells. Although empty viral capsids could be identified in the cytoplasm of approximately 25% of single cells exhibiting an apoptotic morphology, mature virions were hardly observed in these cells. In both coculture and cell-free HHV-7 infection experiments, a significant correlation was observed between the degree of single-cell apoptosis, evaluated by quantitative flow cytometry after propidium iodide staining, and the decrease in the total number of viable cells. Moreover, in cell-free infection experiments, apoptosis showed a positive correlation also with the viral load, monitored by quantitative HHV-7 DNA polymerase chain reaction. Thus, it appears that apoptosis occurred predominantly in uninfected bystander cells but not in productively HHV-7 infected cells. PMID- 9373262 TI - The role of interleukin-10 (IL-10) in IL-15-mediated T-cell responses. AB - Interleukin-15 (IL-15) is a potent T-cell stimulating factor, which has recently been used for pre-clinical in vivo immunotherapy. Here, the IL-15 effect on CD3 stimulated peripheral human T cells was investigated. IL-15 induced a significant T-cell proliferation and upregulated CD25 expression. IL-15 significantly enhanced T-cell production of interferon-gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), and IL-10. Between 10- and 100-fold greater concentrations of IL-15 were necessary to reach a biological effect equivalent to that of IL-2. Blockade of IL-2 binding to the high-affinity IL-2 receptor did not affect the IL 15 effects, suggesting that IL-15 did not act by inducing endogenous IL-2. Exogenously administered IL-10 significantly reduced the IL-15 and IL-2-mediated IFN-gamma and TNF-alpha production, whereas T-cell proliferation and CD25 expression were not affected. The inhibitory effects of exogenously administered IL-10 on T-cell cytokine production appeared indirect, and are likely secondary to decreased IL-12 production by accessory cells. Inhibition of endogenous IL-10 binding to the IL-10 receptor significantly increased IFN-gamma and TNF-alpha release from T cells. These data suggest that endogenous IL-10 can regulate activated T-cell production of IFN-gamma and TNF-alpha via a paracrine negative feedback loop. The observations of this study could be of relevance for the therapeutic use of IL-15 in vivo. PMID- 9373263 TI - Growth and dissemination of Lewis lung carcinoma in plasminogen-deficient mice. AB - Plasminogen activation has been proposed to play a critical role in cancer invasion and metastasis. The effects of complete ablation of plasminogen activation in cancer was studied by inoculation of a metastatic Lewis lung carcinoma expressing high levels of plasminogen activator into plasminogen deficient (Plg-/-) mice and matched control mice. Primary tumors developed in all mice with no difference in the rate of appearance between Plg-/- and control mice. However, the primary tumors in Plg-/- mice were smaller and less hemorrhagic and displayed reduced skin ulceration. In addition, dissemination of the tumor to regional lymph nodes was delayed in Plg-/- mice. Surprisingly, no quantitative differences were observed in lung metastasis between Plg-/- and control mice. In addition, Plg deficiency was compatible with metastasis of the primary tumor to a variety of other organs. Nevertheless, Plg-/- mice displayed a moderately increased survival after primary tumor resection. These findings suggest that plasmin-mediated proteolysis contributes to the morbidity and mortality of Lewis lung carcinoma in mice, but sufficient proteolytic activity is generated in Plg-/- mice for efficient tumor development and metastasis. PMID- 9373265 TI - Expression of constitutively activated human c-Kit in Myb transformed early myeloid cells leads to factor independence, histiocytic differentiation, and tumorigenicity. AB - The cDNAs encoding wild type (WT) human receptor tyrosine kinase c-Kit and a constitutively activated mutant, V816Kit, were introduced into granulocyte macrophage colony-stimulating factor (GM-CSF )-dependent early murine hemopoietic cells, which had been transformed with activated Myb. WTKit cells were able to grow in the presence of the human ligand for Kit, stem cell factor (SCF ), but displayed reduced growth and clonogenic potential in either SCF or GM-CSF compared with the parental cells in GM-CSF. In contrast, V816Kit cells grew without factor at a higher rate than the parental cells in GM-CSF and displayed increased clonogenicity. Dissection of the growth characteristics in liquid culture showed that in the presence of appropriate factors, the different populations had similar proliferation rates, but that V816Kit profoundly increased cell survival compared with WTKit or parental cells. This suggests that the signals transduced by WTKit activated with SCF, and by V816Kit, were not identical. Also, WTKit and V816Kit-expressing cells both varied from the early myeloid progenitor phenotype of the parental cells and gave rise to a small number of large to giant adherent cells that expressed macrophage (alpha-naphthyl acetate) esterase and neutrophil (naphtol-AS-D-chloroacetate) esterase, were highly phagocytic and phenotypically resembled histiocytes. Thus, WTKit activated by SCF and V816Kit were able to induce differentiation in a proportion of Myb transformed myeloid cells. The factor independent V816Kit cells, unlike the parental and WTKit expressing cells, were shown to produce tumors of highly mitotic, invasive cells at various stages of differentiation in syngeneic mice. These results imply that constitutively activated Kit can promote the development of differentiated myeloid tumors and that its oncogenic effects are not restricted to lineages (mast cell and B-cell acute lymphoblastic leukemia), which have been reported previously. Furthermore, the mixed populations of cells in culture and in the tumors phenotypically resembled the leukemic cells from patients with monocytic leukemia with histiocytic differentiation (acute myeloid leukemia-M5c), a newly proposed subtype of myeloid leukemia. PMID- 9373264 TI - Adult patients with de novo acute myeloid leukemia and t(9; 11)(p22; q23) have a superior outcome to patients with other translocations involving band 11q23: a cancer and leukemia group B study. AB - Following reports of childhood acute myeloid leukemia (AML) showing that patients with t(9; 11)(p22; q23) have a better prognosis than those with translocations between 11q23 and other chromosomes, we compared response to therapy and survival of 24 adult de novo AML patients with t(9; 11) with those of 23 patients with other 11q23 translocations [t(11q23)]. Apart from a higher proportion of French American-British (FAB) M5 subtype in the t(9; 11) group (83% v 43%, P = .006), the patients with t(9; 11) did not differ significantly from patients with t(11q23) in terms of their presenting clinical or hematologic features. Patients with t(9; 11) more frequently had an extra chromosome(s) 8 or 8q as secondary abnormalities (46% v 9%, P = .008). All patients received standard cytarabine and daunorubicin induction therapy, and most of them also received cytarabine-based intensification treatment. Two patients, both with t(9; 11), underwent bone marrow transplantation (BMT) in first complete remission (CR). Nineteen patients (79%) with t(9; 11) and 13 (57%) with t(11q23) achieved a CR (P = .13). The clinical outcome of patients with t(9; 11) was significantly better: the median CR duration was 10.7 versus 8.9 months (P = .02), median event-free survival was 6.2 versus 2.2 months (P = .009), and median survival was 13.2 versus 7.7 months (P = .009). All patients with t(11q23) have died, whereas seven (29%) patients with t(9; 11) remain alive in first CR. Seven of eight patients with t(9; 11) who received postremission regimens with cytarabine at a dose of 100 (four patients) or 400 mg/m2 (2 patients) or who did not receive postremission therapy (2 patients) have relapsed. In contrast, 7 (64%) of 11 patients who received intensive postremission chemotherapy with high-dose cytarabine (at a dose 3 g/m2) (5 patients), or underwent BMT (2 patients) remain in continuous CR. We conclude that the outcome of adults with de novo AML and t(9; 11) is more favorable than that of adults with other 11q23 translocations; this is especially true for t(9; 11) patients who receive intensive postremission therapy. PMID- 9373266 TI - Regulation of a graft-versus-leukemia effect by major histocompatibility complex class II molecules on leukemia cells: HLA-DR1 expression renders K562 cell tumors resistant to adoptively transferred lymphocytes in severe combined immunodeficiency mice/nonobese diabetic mice. AB - To understand the role of key molecules in determining the strength and nature of allogeneic T-cell response to leukemia, we transfected HLA-DR1 into the major histocompatibility complex (MHC)-deficient, natural killer (NK)-cell sensitive K562 leukemia cell line. Untransfected K562 cells stimulated NK proliferation in vitro and formed subcutaneous tumors in severe combined immunodeficiency/non obese diabetic (SCID/NOD) mice. Tumor growth was inhibited by adoptive intravenous transfer of fresh unprimed peripheral blood mononuclear cells (PBMC). In contrast, HLA-DR1 transfected cells stimulated CD4(+) T cells, but not NK-cell proliferation in vitro and formed tumors resistant to fresh PBMC in SCID/NOD mice. Tumors not expressing MHC were infiltrated with CD16(+)CD56(+) lymphocytes whereas nonregressing HLA-DR1 expressing tumors showed only a scanty infiltration with both T-cell and NK-cell subsets. The results indicate that MHC class II expression by leukemia cells can determine the effector cell type that it engages. In vivo MHC class II expression rendered K562 cell tumors resistant to NK-cell mediated antitumor reactivity. PMID- 9373267 TI - 12p abnormalities and the TEL gene (ETV6) in childhood acute lymphoblastic leukemia. AB - Although abnormalities involving the short arm of chromosome 12 (12p) are one of the most frequently observed rearrangements in childhood acute lymphoblastic leukemia (ALL), little is known about the frequency of different structural abnormalities and their relationship to the status of the ETV6 (also named TEL) gene in this region. Of 815 children with newly diagnosed ALL, 94 (11.5%) had a total of 104 cytogenetic 12p abnormalities. Loss of genetic material was observed in 67 (64%) of these abnormalities. Cases with 12p alterations had a much lower frequency of hyperdiploidy greater than 50 (7%) than did the ALL population in general, but these cases had a similar distribution of immunophenotype and similar 5-year event-free survival (70% +/- 5% SE v 64% +/- 2%, P = .64). Rearrangement of the ETV6 gene was identified in 36 (56%) of 64 cases evaluated. The ETV6-CBFA2 (TEL-AML1) fusion transcript was found in 25 (66%) of 38 cases evaluated, and all but one of these showed ETV6 rearrangement. Importantly, ETV6 rearrangement was associated with a favorable prognosis (5-year event-free survival: 89% +/- 6% v 60% +/- 1%, P < .01). We conclude that most but not all 12p cytogenetic abnormalities in childhood ALL involve ETV6, and that rearrangement of ETV6 is associated with a favorable treatment outcome. PMID- 9373268 TI - Mitochondrial antisense RNA for cytochrome C oxidase (MARCO) can induce morphologic changes and cell death in human hematopoietic cell lines. AB - To identify essential molecules capable of inducing terminal morphologic maturation and cell death of myeloid progenitor cells, we isolated cDNA clones by functional expression cloning using a library constructed from all-trans retinoic acid (ATRA)-treated human promyelocytic HL-60 cells. Clones which induced morphologic changes in HL-60 cells from blastic cells to mature neutrophilic granulocytes were selected. The isolated positive cDNA clone was demonstrated to encode an antisense RNA for cytochrome c oxidase/serine tRNA derived from a mitochondrial gene (MARCO). When MARCO was expressed in HL-60 cells with the lac switch system, blastic cell morphology became neutrophilic after 48-hour incubation with IPTG, and cell death was observed after 3 days. Also, high molecular weight DNA fragmentation was observed after 36 hours in culture. Similar results were observed using transformants from human K562 cells and CMK cells. RT-PCR analysis revealed that MARCO was transcribed in both ATRA and TNF alpha systems, and also in human blood neutrophilic granulocytes. Following transfection with cytochrome c oxidase expression plasmids, TNF-alpha-induced high molecular weight DNA fragmentation in U937 cells and HL-60 cells was inhibited in these transformants. These results indicate that maturational changes in hematopoietic cells and the process of cell death may be induced by mitochondrial respiratory insufficiency, and also that the mitochondrial gene MARCO may be used as one of the candidates for gene supplementation therapy for the acute leukemias. PMID- 9373269 TI - Modulation of idarubicin-induced apoptosis in human acute myeloid leukemia blasts by all-trans retinoic acid, 1,25(OH)2 vitamin D3, and granulocyte-macrophage colony-stimulating factor. AB - The relationship between differentiation of human myeloid cells and apoptosis remains unclear. Recent studies have shown that terminal differentiation need not necessarily lead to the apoptotic demise of myeloid cells, while other studies have shown that induction of differentiation is associated with increased resistance to apoptosis-inducing agents, such as chemotherapy and gamma irradiation. Such results are pertinent to the treatment of acute myeloid leukemia (AML) and myelodysplastic syndrome, where differentiating agents and hemopoietic growth factors are being combined with chemotherapy to enhance response and limit toxicity. To elucidate the factors governing apoptosis in human AML blasts, we have studied the cytotoxic effect of idarubicin on HL60, U937 and KG1 cells, after incubation with all-trans retinoic acid (ATRA), 1, 25(OH)2 D3, and granulocyte-macrophage colony-stimulating factor (GM-CSF ). We show that prior incubation of human myeloid leukemic cells with ATRA or 1,25(OH)2 D3 induced resistance to idarubicin-induced apoptosis, which was modulated by coincubation with GM-CSF. The altered chemosensitivity of cells depended on the degree of G0/G1 cell-cycle arrest induced by incubation with ATRA, 1, 25(OH)2 D3, and GM-CSF and was independent of differentiation status or Bcl-2 oncoprotein expression. These findings suggest that cell-cycle arrest in human leukemic cells can be induced by exogenous agents and may promote drug resistance. Determining the mechanisms by which cell-cycle arrest is induced may permit understanding of the processes by which the cells escape cytotoxic drug-mediated apoptosis. PMID- 9373270 TI - The CXC-chemokine neutrophil-activating peptide-2 induces two distinct optima of neutrophil chemotaxis by differential interaction with interleukin-8 receptors CXCR-1 and CXCR-2. AB - The CXC-chemokines interleukin-8 (IL-8), neutrophil-activating peptide-2 (NAP-2), and melanoma growth-stimulatory activity (MGSA) are chemoattractants with high selectivity for neutrophils. Although IL-8 has been shown to act as an extremely potent mediator, reports on NAP-2 and MGSA are still contradictory. Here we show for the first time that NAP-2 and MGSA induce two distinct optima of neutrophil chemotaxis. A first optimum is elicited within a concentration range as low as it is characteristic for IL-8. However, a second optimum appears at more than 200 fold higher stimulus concentrations, at which IL-8 is inactive. Investigating the involvement of the two chemokine receptors CXCR-1 and CXCR-2 in NAP-2-mediated chemotaxis, we observe that the cells become desensitized to the first optimum of the chemokine after selective downregulation of CXCR-2, while both optima disappear upon simultaneous downregulation of both receptors. Blocking monoclonal antibodies (MoAbs) specific for CXCR-2 or CXCR-1 either suppress the first optimum of NAP-2-induced chemotaxis or drastically reduce the second one, respectively. These results provide evidence that both receptors are involved in NAP-2-induced neutrophil chemotaxis, with CXCR-2 rendering the cells responsive to low dosages of the chemokine, and with CXCR-1 extending their responsiveness to NAP-2 dosages higher by several orders of magnitude. PMID- 9373271 TI - Granulocyte colony-stimulating factor upregulates the vacuolar proton ATPase in human neutrophils. AB - We have previously shown that granulocyte colony-stimulating factor (G-CSF ) delays spontaneous neutrophil apoptosis through activation of the vacuolar proton ATPase (v-ATPase). We have now examined the regulation of the v-ATPase in neutrophils exposed to G-CSF in vitro. When neutrophils were cultivated in the absence of G-CSF, the 57-kD cytosolic B subunit of the v-ATPase disappeared within 1 to 2 hours, its loss preceding the nuclear changes of apoptosis and coinciding with the onset of acidification. By contrast, in neutrophils cultured for 2 hours in the presence of G-CSF, the amount of the 57-kD subunit was similar to that in freshly isolated neutrophils. However, inhibition of protein synthesis with cycloheximide and actinomycin D led to loss of the 57-kD subunit even in the presence of G-CSF. These results indicated that ongoing protein synthesis was required to maintain the v-ATPase, and further suggested that G-CSF acted, at least in part, by maintaining synthesis of the 57-kD cytosolic subunit. G-CSF also promoted the translocation of the 57-and 33-kD cytosolic v-ATPase subunits to the membrane. Our findings suggested two coordinate mechanisms by which the activity of the v-ATPase could be increased by G-CSF: the synthesis of cytosolic v-ATPase subunits and their translocation to the membrane. PMID- 9373272 TI - The human beta globin locus introduced by YAC transfer exhibits a specific and reproducible pattern of developmental regulation in transgenic mice. AB - The human beta globin locus spans an 80-kb chromosomal region encompassing both the five expressed globin genes and the cis-acting elements that direct their stage-specific expression during ontogeny. Sequences proximal to the genes and in the locus control region, 60 kb upstream of the adult beta globin gene, are required for developmental regulation. Transgenic studies have shown that altering the structural organization of the locus disrupts the normal pattern of globin gene regulation. Procedures for introducing yeast artificial chromosomes (YACs) containing large genetic loci now make it possible to define the sequences required for stage-restricted gene expression in constructs that preserve the integrity of the beta globin locus. We demonstrate that independent YAC transgenic lines exhibit remarkably similar patterns of globin gene expression during development. The switch from gamma to beta globin predominant expression occurs between day 11.5 and 12.5 of gestation, with no more than twofold differences in human beta globin mRNA levels between lines. Human beta globin mRNA levels were twofold to fourfold lower than that of mouse betamaj, revealing potentially significant differences in the regulatory sequences of the two loci. These findings provide an important basis for studying regulatory elements within the beta globin locus. PMID- 9373273 TI - Thrombosis and secondary hemochromatosis play major roles in the pathogenesis of jaundiced and spherocytic mice, murine models for hereditary spherocytosis. AB - Jaundiced mice, ja/ja, suffer from a severe hemolytic anemia caused by a complete deficiency of erythroid beta-spectrin. We used these mice as a model to investigate the pathophysiological consequences of the deficiency, including the effects in the nonerythroid tissues where this protein is expressed. Because the ja/ja mice rarely survive beyond the fourth postnatal day, methods were assessed for extending lifespan into adulthood. Neonatal transfusion increased lifespan to a mean of 3.7 months, allowing a more complete characterization of the pathophysiology. Blood parameters and histopathology of the jaundiced mouse were compared with that from spherocytic mice, which have a hemolytic anemia caused by deficiency of erythroid alpha-spectrin, yet can survive the postnatal period transfusion free. The adult jaundiced and spherocytic mice present with greatly decreased hematocrit and red blood cell counts, reticulocytosis, and bilirubinemia, leading secondarily to hepatosplenomegaly and cardiomegaly. Jaundiced and spherocytic mice were analyzed histopathologically between 1.0 and 9.5 months of age. Interestingly, the complete absence of erythroid beta-spectrin in jaundiced mice leads to no detectable structural defects in brain, cardiac, or skeletal muscles. However, fibrotic lesions and lymphocytic infiltration were observed in cardiac tissue from 4 of 13 jaundiced mice and 15 of 15 spherocytic mice, and thrombi were detected at either the atrioventricular valves or within the atria of 2 of 13 jaundiced mice and 15 of 15 spherocytic mice. In addition, all affected mice had a progressive renal hemosiderosis concurrent with hydronephrosis and glomerulonephritis. The severity of the renal disease and its presence in all moribund mice suggests kidney failure rather than the fibrotic heart lesions as the major cause of death in these mice. PMID- 9373274 TI - Systematic enhancement of polymerization of recombinant sickle hemoglobin mutants: implications for transgenic mouse model for sickle cell anemia. AB - To provide quantitative information on the sites that promote polymerization of sickle hemoglobin (HbS) after formation of the initial hydrophobic bond involving Val-6(beta) [E6V(beta)] and also to provide hemoglobins with an enhanced polymerization that could be used in a mouse model for sickle cell anemia, we have expressed recombinant double, triple, and quadruple HbS mutants with substitutions on both the alpha- and beta-chains, E6V(beta)/E121R(beta), D75Y(alpha)/E6V(beta)/E121R(beta) and D6A(alpha)/D75Y(alpha)/E6V(beta)/E121R(beta). These recombinant hemoglobins were extensively characterized by high-performance liquid chromatography analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, isoelectric focusing, amino acid analysis, and mass spectroscopy. They retained the functional properties of the Hb tetramer and polymerized in a linear manner at progressively lower Hb concentration as a function of the degree of substitution, suggesting that these remote sites (alphaD6A, alphaD75Y, and betaE121R) on the alpha- and beta-chains exhibit additive, enhanced polymerization properties. The quadruple mutant has a polymerization concentration close to that of the purified SAD hemoglobin from transgenic mouse red blood cells consisting of HbS, Hb Antilles, and Hb D-Punjab. Normal mouse Hb increases the polymerization concentration of each mutant. Thus, the general approach of using recombinant Hbs as described here should prove useful in elucidating the quantitative aspects of the mechanism of HbS polymerization and in identifying the contribution of individual sites to the overall process. The strategy described here demonstrates the feasibility of a systematic approach to achieve future recombinant HbS mutants that could provide a new generation of the transgenic mouse model for sickle cell anemia. PMID- 9373275 TI - Prevalence and natural history of hepatitis C infection in patients cured of childhood leukemia. AB - The aim of this study was to ascertain prevalence and natural history of hepatitis C virus (HCV) infection in a large cohort of patients cured of childhood leukemia who had been followed prospectively for liver disease for at least 10 years since chemotherapy withdrawal: 114 consecutive patients entered the study. Liver function tests and ultrasonography were used to assess presence of liver disease. Patients were tested for antibody to HCV and for serum HCV-RNA at the end of chemotherapy and at the end of follow-up. At chemotherapy withdrawal, 56 patients (49%) were HCV-RNA positive, often without detectable anti-HCV, and in these cases, transaminase levels were more elevated during (P = .08) and after (P = .04) chemotherapy compared with HCV-RNA negative cases. Patients were then followed-up 13 to 27 years (mean, 17) after chemotherapy withdrawal. During this period, 38 initially anti-HCV negative patients seroconverted to anti-HCV and 17 initially anti-HCV positive cases lost reactivity. Forty patients were persistently HCV-RNA positive in serum, while 16 initially viremic patients became HCV-RNA negative during follow-up. At the end of the observation period, a persistent transaminase elevation was detected only in four HCV-RNA positive and anti-HCV positive cases, while no patient developed signs or symptoms of decompensated liver disease. Thus, hepatitis C was a frequent finding in long-term survivors after chemotherapy. It was associated with an atypical serologic profile and did not cause severe liver impairment over a period of 13 to 27 years. PMID- 9373276 TI - High rates of hepatitis G virus infection in multitransfused patients with hemophilia. AB - The parallel measurement of serum antibodies to the hepatitis G virus (anti-HGV) and of viremia (HGV-RNA) should improve our understanding of HGV transmission by coagulation factor concentrates. The aim of this study was to assess the relationship between HGV, the type of concentrate infused, and liver disease in multitransfused hemophiliacs. To this end, anti-HGV and HGV-RNA were evaluated by an enzyme-linked immunosorbent assay and a nested-polymerase chain reaction assay in patients treated lifelong with nonvirus-inactivated plasma-derived concentrates (n = 128), virus-inactivated concentrates (n = 33), or recombinant factors (n = 7), and in 200 regular blood donors. The prevalence of serum HGV-RNA and anti-HGV was higher in the recipients of nonvirus-inactivated factors than in blood donors (HGV-RNA: 9% v 1.5%, P = .002; anti-HGV: 32% v 5%, P < .0001). In the recipients of virus-inactivated concentrates the prevalences of these markers were similar to those in blood donors (HGV-RNA: 3% v 1.5%; anti-HGV: 15% v 5%). The prevalence of either marker in the recipients of nonvirus-inactivated concentrates was higher than in the recipients of virus-inactivated factors (39% v 18%, P = .04). The former group had serum hepatitis C virus (HCV) RNA or anti HCV more frequently than the latter group (HCV-RNA: 86% v 15%, P < .0001; anti HCV: 96% v 18%, P < .0001). Serum alanine aminotransferase was persistently high in 83 (81%) patients with HCV-RNA alone, in 8 (89%) with HCV/HGV coinfection, and in none of the three patients with HGV-RNA only. Thus, HGV infection in hemophiliacs is more common than previous studies of HGV-RNA prevalence have suggested, but it resolved in most cases and caused chronic viremia only in a small number of patients, without biochemical evidence of persistent liver damage. PMID- 9373278 TI - Synchronized cell-cycle induction of engrafting long-term repopulating stem cells. AB - We have recently defined the window for marrow stem cell homing into nonablated hosts as the first 24 hours posttransplant. Within this homing window, donor cells rapidly cleared from the peripheral blood and lungs and plateaued in the marrow. We have now assessed the cell-cycle status of the engrafting cells capable of contributing to long-term hematopoiesis using administration of hydroxyurea (HU), a chemotherapy agent with S-phase cell-cycle specificity. HU was given at very short periods following a male bone marrow transplant (0, 3, 6, 12, and 15 hours) into female nonablated hosts, and donor cell engraftment was analyzed after 6 weeks. The data show that quickly after transplant (12 hours), greater than half of the engrafting cells capable of contributing long-term to all levels of the hematopoietic hierarchy are in S-phase. Analysis after 6 weeks included whole bone marrow, peripheral blood, primitive cells with high proliferative potential, and mature lineage-restricted marrow cells. These donor cells appear to be naturally synchronized. When HU was administered at any of the other time points, there was little evidence of cell death 6 weeks postengraftment. PMID- 9373277 TI - Gene transfer into marrow repopulating cells: comparison between amphotropic and gibbon ape leukemia virus pseudotyped retroviral vectors in a competitive repopulation assay in baboons. AB - Many diseases might be treated by gene therapy targeted to the hematopoietic system, but low rates of gene transfer achieved in humans and large animals have limited the application of this technique. We have developed a competitive hematopoietic repopulation assay in baboons to evaluate methods for improving gene transfer and have used this method to compare gene transfer rates for retroviral vectors having an envelope protein (pseudotype) from amphotropic murine retrovirus with similar vectors having an envelope protein derived from gibbon ape leukemia virus (GALV). We hypothesized that vectors with a GALV pseudotype might perform better based on our previous work with cultured human hematopoietic cells. CD34(+) marrow cells from each of four untreated baboons were divided into two equal portions that were cocultivated for 48 hours with packaging cells producing equivalent titers of either amphotropic or GALV pseudotyped vectors containing the neo gene. The vectors contained small sequence differences to allow differentiation of cells genetically marked by the different vectors. Nonadherent and adherent cells from the cultures were infused into animals after they received a myeloablative dose of total body irradiation. Polymerase chain reaction (PCR) analysis for neo gene-specific sequences in colony-forming unit-granulocyte-macrophage from cell populations used for transplant showed gene transfer rates of 2.7%, 7.1%, <15%, and 3.9% with the amphotropic vectors and 7.1%, 11.3%, <15%, and 26.4% with the GALV pseudotyped vector. PCR analysis of peripheral blood and marrow cells after engraftment showed the neo gene to be present in all four animals analyzed at levels between 0.1% and 5%. Overall gene transfer efficiency was higher with the GALVpseudotyped vector than with the amphotropic vectors. Southern blot analysis in one animal confirmed a gene transfer efficiency of between 1% and 5%. The higher gene transfer efficiency with the GALV-pseudotyped vector correlated with higher levels of GALV receptor RNA compared with the amphotropic receptor in CD34(+) hematopoietic cells. These results show that GALV-pseudotyped vectors are capable of transducing baboon marrow repopulating cells and may allow more efficient gene transfer rates for human gene therapy directed at hematopoietic cells. In addition, our data show considerable differences in gene transfer efficiency between individual baboons, suggesting that a competitive repopulation assay will be critical for evaluation of methods designed to improve gene transfer into hematopoietic stem cells. PMID- 9373279 TI - Interleukin-12 preserves the graft-versus-leukemia effect of allogeneic CD8 T cells while inhibiting CD4-dependent graft-versus-host disease in mice. AB - We have recently demonstrated that a single injection of 4,900 IU of interleukin 12 (IL-12) on the day of bone marrow transplantation (BMT) markedly inhibits acute graft-versus-host disease (GVHD) in a fully major histocompatibility complex plus minor antigen-mismatched BMT model (A/J --> B10, H-2(a) --> H-2(b)), in which donor CD4(+) T cells are required for the induction of acute GVHD. We show here that donor CD8-dependent graft-versus-leukemia (GVL) effects against EL4 (H-2(b)) leukemia/lymphoma can be preserved while GVHD is inhibited by IL-12 in this model. In mice in which IL-12 mediated a significant protective effect against GVHD, marked GVL effects of allogeneic T cells against EL4 were observed. GVL effects against EL4 depended on CD8-mediated alloreactivity, protection was not observed in recipients of either syngeneic (B10) or CD8-depleted allogeneic spleen cells. Furthermore, we analyzed IL-12-treated recipients of EL4 and A/J spleen cells which survived for more than 100 days. No EL4 cells were detected in these mice by flow cytometry, tissue culture, adoptive transfer, necropsies, or histologic examination. Both GVL effects and the inhibitory effect of IL-12 on GVHD were diminished by neutralizing anti-interferon-gamma (IFN-gamma) monoclonal antibody. This study demonstrates that IL-12-induced IFN-gamma production plays a role in the protective effect of IL-12 against GVHD. Furthermore, IFN-gamma is involved in the GVL effect against EL4 leukemia, demonstrating that protection from CD4-mediated GVHD and CD8-dependent anti-leukemic activity can be provided by a single cytokine, IFN-gamma. These observations may provide the basis for a new approach to inhibiting GVHD while preserving GVL effects of alloreactivity. PMID- 9373280 TI - Day-case (ambulatory) laparoscopic surgery. Let us sing from the same hymn sheet. PMID- 9373281 TI - Selection criteria for laparoscopic cholecystectomy in an ambulatory care setting. AB - BACKGROUND: The ambulatory care center offers patient convenience and reduced costs after uneventful laparoscopic cholecystectomy. METHODS: A prospectively accumulated database of 1,750 cholecystectomies performed by one surgeon in a hospital setting was analyzed to test criteria for ambulatory cholecystectomy. Proposed criteria included age less than 65, absence of upper abdominal operations, and elective operations in healthy patients at low risk for common bile duct stones. RESULTS: Of 1,750 cholecystectomies, only 605 patients met all criteria for outpatient care. Discharge (from the in-hospital setting) was accomplished within 24 h of operation in 92% (first 3 years) and 98% (last 4 years) of selected cases. Only one patient (0.2%, 1/605) was converted to an open procedure; another was readmitted 30 h postoperatively with hemorrhage from the liver bed. CONCLUSIONS: Laparoscopic cholecystectomy can be performed safely in an ambulatory care setting, given careful selection and education of patients and documented experience of the surgical team. PMID- 9373282 TI - Is outpatient cholecystectomy safe for the higher-risk elective patient? AB - BACKGROUND: This study was done to determine the safety of outpatient cholecystectomy for the higher-risk patient. METHODS: All patients over age 70 or with American Society of Anesthesiologists physical status classification of 3 or greater, from all 515 consecutive patients booked for elective cholecystectomy between April 1, 1994, and March 31, 1996, were reviewed. RESULTS: Of 85 higher risk patients, 77 were booked as outpatients. Sixty-one were successfully completed as outpatients, with no complications or readmissions related to their outpatient status. Of 24 admitted patients, 15 had specific indications for hospitalization. Nine were admitted for reasons of "precaution." One of these developed a complication, possibly related to her inpatient status. The other eight could have been managed as outpatients. CONCLUSIONS: Outpatient cholecystectomy is safe for the higher-risk patient. Patients who recover uneventfully from surgery can be discharged without harmful effects. "Precautionary" hospitalization may be harmful. PMID- 9373283 TI - Ambulatory laparoscopic fundoplication. AB - BACKGROUND: Increasingly larger series of laparoscopic fundoplications (LF) are being reported. A well-documented advantage of the laparoscopic approach is shortened hospital stay. Most centers report typical lengths of stay (LOS) for LF of 2-3 days. Our success with LF with a LOS of 1 day led to an attempt at performing LF on an ambulatory basis. METHODS: Sixty-one consecutive patients with appropriate criteria for LF underwent surgery at our institution. Patients were counseled by the authors as to the usual postop course and progression of diet. All patients received preemptive analgesia (PEA) consisting of perioperative ketorolac and preincisional local infiltration with bupivicaine. Anesthetic management included induction with propofol, high-dose inhalational anesthetics, minimizing administration of parenteral narcotics, and avoidance of reversal of neuromuscular blockade. Immediate postop pain management included parenteral ketorolac and oral hydro- or oxycodone. All patients were given oral fluids and soft solids after transfer from the recovery room to the postoperative observation unit. Two patients were excluded from ambulatory consideration due to excessive driving distance from our hospital. Another two were hospitalized for observation after experiencing intraoperative technical problems. RESULTS: Of 57 patients in whom same-day discharge was attempted, there were three failures requiring overnight hospitalization: All were due to pain and nausea; one patient also suffered transient urinary retention. There were no adverse outcomes related to early discharge, and there were no readmissions. One patient returned to the emergency room after delayed development of urinary retention. Median time from conclusion of operation to discharge was less than 5 h. No patients expressed dissatisfaction with early discharge on follow-up interview. CONCLUSIONS: LF can be safely performed as an ambulatory procedure. Analgesic and anesthetic management should be tailored to minimize nausea and provide adequate pain control. PMID- 9373285 TI - Selection of locally advanced gastric carcinoma by preoperative staging laparoscopy. AB - BACKGROUND: The present study is a prospective evaluation of immediate preoperative laparoscopy compared to ultrasound/computed tomography (US/CT) staging for gastric cancer in a series of 100 patients observed at two major Italian hospitals from April 1995 through September 1996. METHODS: After a complete preoperative work-up all c-M0 patients underwent laparoscopy immediately prior to an eventual surgical exploration. pTNM was considered as the gold standard for the evaluation of the results. RESULTS: Laparoscopy detected 21 unsuspected M+ cases out of 100. As regards locally advanced tumors, laparoscopy showed a sensibility of 69.7% for T3 and 89.6% for T4, significantly higher than US/CT staging (23.2% and 48.3%, respectively; p < 0.02). In this series laparoscopic staging altered clinical staging in 58% of cases. CONCLUSIONS: This procedure plays two crucial roles in the preoperative evaluation of advanced gastric cancer: It makes it possible to avoid unnecessary surgical exploration in M+ cases and, to date, it represents the most reliable and economic tool for the selection of locally advanced tumors in the light of neoadjuvant treatment. PMID- 9373284 TI - Video-laparoscopic staging of gastric cancer. A prospective multicenter comparison with noninvasive techniques. AB - BACKGROUND: The high proportion of gastric carcinomas present in an unresectable stage, together with the emergence of multimodal treatments, increases the usefulness of objective staging methods that avoid unnecessary laparotomies. METHODS: A prospective evaluation of the accuracy of laparoscopy in the staging of 71 patients with gastric adenocarcinoma is presented. Serosal infiltration, retroperitoneal fixation, metastasis to lymph nodes, peritoneal and liver metastasis, and ascites were determined in the staging workup. Sensitivity, specificity, and predictive values were calculated and compared with those obtained with ultrasonography (US) and computed tomography (CT). RESULTS: The diagnostic accuracy of laparoscopy in the determination of resectability was 98.6%. Consequently, over 40% of patients were spared unnecessary laparotomies. Laparoscopy yielded diagnostic indices superior to US and CT for all the tumoral attributes studied. Our technique permits accurate assessment and pathologic verification of liver and the peritoneal and retroperitoneal extent of tumor invasion in the majority of patients. CONCLUSIONS: Laparoscopy in gastric adenocarcinoma is a reliable technique that provides accurate assessment of resectability and stage, thus avoiding unnecessary laparotomies in patients in whom surgical palliation is not indicated. A stepwise diagnostic workup combining imaging and minimally invasive techniques is proposed. PMID- 9373286 TI - The effect of laparoscopy on the movement of tumor cells and metastasis to surgical wounds. AB - BACKGROUND: A variety of mechanisms have been proposed to explain tumor growth in port sites following laparoscopic cancer surgery. We devised two experimental models to determine whether carbon dioxide (CO2) insufflation during laparoscopic surgery influences the movement of tumor cells and leads to tumor implantation and growth in surgical wounds. METHODS: Model 1: Viable adenocarcinoma cells were introduced into the upper abdomen of six syngeneic immune-competent rats during laparoscopy with CO2 insufflation; the same procedure was followed for a further six rats during gasless laparoscopy. A length of plastic tubing introduced through the anterolateral aspect of the rats' left lower abdominal wall was used to vent the insufflation gas through the abdomen of a recipient rat for 30 min. After 21 days, the peritoneal cavity and surgical wounds of the recipient rat were examined for implanted tumor. Model 2: A suspension of radiolabeled adenocarcinoma cells was introduced into the upper abdomen of five rats during laparoscopy with CO2 insufflation and an additional five rats during gasless laparoscopy. A length of plastic tubing introduced through the anterolateral aspect of the left lower abdominal flank was used to vent the insufflation gas through phosphate-buffered saline solution. After 30 min, the solution was counted for radioactivity. RESULTS: Tumor growth occurred at the site of both the insufflation and venting ports in the second rat in five of the six rats from the group undergoing insufflation, but it was found in none of the gasless laparoscopy group (p = 0.015). In the second model, significant transfer of tumor cells to the vented gas occurred only in the rats undergoing laparoscopy with insufflation (median, 2.71% versus 0% of the introduced labeled cells; p = 0.008). CONCLUSIONS: Carbon dioxide insufflation results in tumor dissemination during laparoscopy, leading to port site metastasis. Gasless laparoscopy may prevent this problem. PMID- 9373287 TI - VATS-guided epicardial pacemaker implantation. Hand-sutured fixation of atrioventricular leads in an experimental setting. AB - BACKGROUND: In neonates and infants epicardial stimulation may be preferred to endocardial stimulation because of growth-associated lead problems and the risk of vascular complications associated with transvenous electrodes. This study analyzes the feasibility of atrioventricular implantation of a new epicardial lead using the video-assisted thoracic surgical (VATS) technique in an animal model. METHODS: Bipolar steroid-eluting epicardial leads were implanted in seven young white pigs. In five animals bipolar atrial and ventricular pacing leads (n = 10) were inserted and fixed by the VATS technique, while two animals served as controls and underwent implantation through anterolateral thoracotomy. Surgical feasibility, pacing, and sensing thresholds of the leads as well as hemodynamic parameters during pacing were studied. Histological changes beneath the electrodes were evaluated 1 week after the implantation. RESULTS: All animals survived the pacemaker lead implantation. One animal which underwent thoracotomy died because of irreversible ventricular fibrillation induced by rapid ventricular pacing. One animal in the VATS group exhibited intraoperative herniation of the heart through the pericardial window. All animals with left sided VATS implantations demonstrated good individual pacing and sensing threshold values. The mean cardiac output was 1.6 times higher during AAI-mode pacing as compared to VVI-mode pacing at a heart rate of 140/min. One animal died postoperatively due to respiratory failure. No displacements of the pacemaker leads were observed in the survivors. CONCLUSION: While VATS-guided implantation of epicardial, atrial, and ventricular leads is feasible, technical improvements of the system are mandatory for safe clinical application. PMID- 9373288 TI - The dramatic reality of biliary tract injury during laparoscopic cholecystectomy. An anonymous multicenter Belgian survey of 65 patients. AB - BACKGROUND: Most reports concerning the outcome of patients with biliary tract injury during laparoscopic cholecystectomy come from tertiary referral centers, and results could be very different in the everyday practice of community surgeons. OBJECTIVE: The objective is to define the presentation, mechanisms, results of treatment, and long-term outcome of biliary tract injuries during laparoscopic cholecystectomy in the setting of a community surgeon's practice. METHODS: An anonymous retrospective multicenter survey of 9,959 patients who underwent laparoscopic cholecystectomy was conducted by the Belgian Group for Endoscopic Surgery, composed mainly of community general surgeons. RESULTS: Sixty five patients with bile duct injury were reported on; the incidence was 0.5%, varying from 0. 35 to 1.3% according to the experience of the surgeon. Thirty four percent of ductal injuries occurred with experienced surgeons, often in association with local predisposing risk factors. Injury occurred in 87% of cases during dissection of the Calot triangle, with severe injury occurring in 46% of patients. Intraoperative cholangiography was performed in 34% of patients and was associated with a significantly improved operative detection rate of injury (68% vs 32%, p = 0.007). Operative detection of injury occurred in 45% of patients; diffuse bile ascitis was encountered postoperatively in 29%. The overall mortality was 9%, the postoperative biliary complication rate 31%, and the reintervention rate 14%. During a median follow-up of 49 months (range, 3-78 months), 20 of the 61 surviving patients (33%) had recurrent biliary strictures. Multivariate analysis demonstrated that the age of the patient (odds ratio: 0.893) and the presence of biliary peritonitis (odds ratio: 0.061) were independent predictive factors for mortality and that the age of the patient (odds ratio: 1.049) and the occurrence of postoperative biliary complications (odds ratio: 0.161) after the initial biliary repair were independent predictive factors for late biliary stricture. CONCLUSIONS: Biliary tract injury is associated with significant mortality and complications in the practice of Belgian community surgeons. Intraoperative detection of ductal injury by the routine use and a correct interpretation of intraoperative cholangiography improved outcome. The impact of the primary biliary repair on long-term outcome is an argument to refer these patients to specialized multidisciplinary experts. The results highlight the importance of surgical experience, proper selection of patients for laparoscopic cholecystectomy, and conversion to laparotomy in difficult cases. PMID- 9373289 TI - Minimally invasive treatment of acute biliary pancreatitis. AB - BACKGROUND: Stones of the common bile duct are the most important factor in acute pancreatitis (AP). Endolaparoscopic surgery plays a well-recognized role in the treatment of this pathology. METHODS: From January 1992 to December 1995 we observed 62 cases of acute biliary pancreatitis (ABP). In 57 cases (= 93.4%) we proposed a minimally invasive treatment, based on performance of endoscopic retrograde cholangiopancreatography (ERCP) combined with endoscopic sphincterotomy (ES) and then of laparoscopic cholecystectomy (LC). RESULTS: ERCP was attempted in emergency in 40/57 cases and successfully done in 34 cases. An ES was performed in all but two cases. In 51 patients we performed LC. The overall morbidity was 8. 9% with no mortality. CONCLUSIONS: In the case of ABP early treatment can achieve the restoration of patency of the papilla, reducing the risk of associated cholangitis and the development of pancreatic necrosis. The cholecystectomy prevents the risk of relapse of ABP. PMID- 9373290 TI - Tailored augmentation of the lower esophageal sphincter in experimental antireflux operations. AB - BACKGROUND: Modern upper GI function studies allow for the detection of several pathophysiological factors that contribute to gastroesophageal reflux disease. The information obtained can lead to therapeutic consequences in patients with an indication for a surgical intervention, i.e., an individualized choice of antireflux procedure according to the existing pathophysiologic defect. METHODS: In an experimental study on mini-pigs the mechanical effect of four standardized antireflux operations (anterior and posterior 180 degrees hemifundoplication, Nissen-DeMeester and Nissen-Rossetti 360 degrees fundoplication) on the lower esophageal sphincter (LES) was investigated. It was the aim of the study to objectively determine the extent of changes in pressure and length parameters at the LES according to the performed antireflux procedure. RESULTS: It could be demonstrated that different degrees of fundic wrap formation lead to a proportional mechanical effect at the LES according to the size of this wrap. CONCLUSION: Choosing a distinct type of fundoplication will allow for a tailored augmentation of the LES according to the individual functional defect. PMID- 9373291 TI - Video-assisted thoracoscopic treatment of spinal lesions in the thoracolumbar junction. AB - BACKGROUND: The endoscopic treatment of spinal lesions in the thoracolumbar junction (T11-L2) poses a great challenge to the surgeon. From November 1, 1995 to December 31, 1996, we successfully used a combination of video-assisted thoracoscopy and conventional spinal instruments to treat 38 patients with anterior spinal lesions. Twelve of them had lesions in the thoracolumbar junction. METHODS: The so-called extended manipulating channel method was used to perform vertebral biopsy, discectomy, decompressive corpectomy, interbody fusions, and/or internal fixations in these patients. The size of the thoracoscopic portals was greater than usual in order to allow conventional spinal instruments and a thoracoscope to enter the chest cavity freely and be manipulated by techniques similar to those used in standard open surgical procedures. In this series, the procedures were performed by using either a three portal approach (2. 5-3.5 cm) or a modified two-portal technique involving a 5-6 cm larger incision and a small one for introducing the scope. RESULTS: None of the operations resulted in injury to the great vessels, internal organs, or spinal cord. The total time for the operation ranged from 1.5 to 4.5 h (average, 3); and the total blood loss ranged from 50 to 3000 cc (average, 1050). One patient was converted to an open procedure due to severe pleural adhesion. Complications included two instances of transient intercostal neuralgia, one superfical wound infection, and one residual pneumothorax. CONCLUSIONS: The video assisted technique with the extended manipulating channel method presented in this report simplifies thoracoscopic spinal surgery in the thoracolumbar junction and makes it easier. It avoids division of the diaphragm, removal of the rib, and wide spread of the intercostal space, and it allows greater control of intraoperative vessel bleeding. Using this technique, the number of portals required during the procedure can be reduced. In addition, the technique reduces the endoscopic materials required, thus lowering overall cost. It is an effective and promising approach. PMID- 9373292 TI - Diagnostic ultrasound of acute colonic diverticulitis by surgical residents. AB - BACKGROUND: Recent studies have documented the feasibility of ultrasonography (US) to diagnose acute colonic diverticulitis (ACD). This prospective observational trial determined the sonomorphology of ACD and evaluated the diagnostic accuracy of routine US performed on admission by surgeons in training. METHODS: Fifty-seven consecutive patients with a confirmed episode of ACD were entered into this study, and the sonomorphology of the involved colon was assessed. US findings were compared to the results of the clinical evaluation and correlated to the clinicopathological outcome. RESULTS: The sonomorphology of ACD was characterized by segmental inflammatory transformation of the colon averaging 9.9 +/- 3.2 cm (range, 6-20) in length and visualized as target phenomena of a mean 3.5 +/- 0.8 cm (range, 2.4-4.8) width. Targets were caused by hypoechogenic thickening of the colonic wall of an average 7.7 +/- 2. 6 mm (range, 4-18). In 40% of cases, a hyperechogenic halo representing peridiverticulitis (average width, 2.3 +/- 0.6; range, 1.2-3 cm) was noted. Diverticula were seen in almost half of the cases. Of the 57 cases with confirmed ACD, the diagnosis was made by US in 48, for a global accuracy of 84.2%. US was false negative in nine patients, suggesting perforated appendicitis in five cases and acute appendicitis in one (the final diagnoses were perforated sigmoid diverticulitis in five cases and cecal diverticulitis in one case). In three patients, US was nondiagnostic. CONCLUSION: In the hands of sonographically trained surgeons, ultrasound is a useful modality to image acute colonic diverticulitis. US reveals diagnostic sonomorphology in most cases of ACD and therefore facilitates early confirmation of the diagnosis and assessment of severity. PMID- 9373293 TI - Needle and trocar injury during laparoscopic surgery in Japan. AB - BACKGROUND: With the growth and sophistication of laparoscopic surgery, increased attention is now being focused on safety and complications. METHODS: In an attempt to address questions regarding the safety of laparoscopic surgery, a retrospective study of the time period from January 1991 to December 1995 was conducted by the Study Group of Endoscopic Surgery in Kyushu, Japan. RESULTS: The response rate was 84.4% (152 of 180 hospitals). During the last 5 years 17,626 patients underwent endoscopic operations and 87.5% (15, 422 patients) had laparoscopic surgery while 12.5% (2,204 patients) underwent thoracoscopic surgery. In 96.6% of the hospitals a minimal open laparotomy was used. Among the various operations, a cholecystectomy was performed in the largest number of patients (13, 787). The total number of complications was 415 (2.7%), of which 156 (37.6%) were related to needle or trocar insertion. Visceral injury was found in 22 patients (0.14%): major vessel injury in 10, gastrointestinal tract injury in 11, and liver injury in one patient. Abdominal wall injury was seen in 79 patients (0.52%), bleeding in 70 (0.46%), and a hernia in 9 (0.06%). Extraperitoneal insufflation occurred in 55 patients (0.36%). There was no mortality. The complication rate significantly decreased year by year after the use of laparoscopic surgery began. CONCLUSIONS: The most common complications of laparoscopic surgery are related to needle and trocar insertion. These are preventable by placement under direct vision with verification of the intraperitoneal location of the needle and trocar. PMID- 9373294 TI - Laparoscopic Nissen fundoplication in children under 2 years of age. AB - BACKGROUND: Antireflux operations have been recommended for infants and children suffering from complications related to gastroesophageal reflux (GER). In recent years, the laparoscopic approach has been used increasingly for antireflux surgery in adult patients. This is our initial experience with Nissen fundoplication in infants and children under 2 years of age. PATIENTS: We operated on 11 patients weighing between 3.0 and 10.0 kg. The main indications for surgery were GER-induced aspiration pneumonia and failure to thrive, in spite of intensive conservative treatment. All patients except one had an associated neurological abnormality, including six patients with familial dysautonomia. RESULTS: All attempted operations were completed successfully laparoscopically, with only a few postoperative complications and acceptable short-term results. The clinical considerations and technical aspects unique to this specific group of patients are discussed. CONCLUSION: Laparoscopic Nissen fundoplication is feasible, safe, and effective, even in very small babies. PMID- 9373295 TI - Laparoscopic cecal ligation and puncture in the rat. Surgical technique and preliminary results. AB - BACKGROUND: We describe a technique of laparoscopic cecal ligation and puncture (CLP) in the rat analogous to open CLP which may facilitate the study of minimally invasive surgery (MIS) and peritonitis. METHODS: Forty-four rats were randomized to either laparoscopic or open CLP and their 3-day mortality was recorded. Autopsies were performed for peritoneal fluid cultures, measurement of the length of ligated cecum, and scoring of the degree of cecal necrosis. RESULTS: Laparoscopic CLP required slightly longer operating times compared to open CLP (average 15.6 vs 13.1 min, p = 0.002). Three-day postoperative mortality was 36.4% and 22.7% for open and laparoscopic CLP, respectively (p = NS). There were no differences in the length of ligated cecum or the cecal necrosis score between the open and laparoscopic CLP groups. CONCLUSION: Laparoscopic CLP is feasible and produces a fecal peritonitis with similar characteristics to those of traditional open CLP. PMID- 9373296 TI - Laparoscopically assisted abdominoperineal resection and simultaneous total anorectal reconstruction with electrostimulated static-dynamic graciloplasty. AB - Bilateral electrostimulated graciloplasty, performed in a "static-dynamic" configuration around a perineal colostomy (total anorectal reconstruction-TAR), has been proven a reliable way to restore continence in patients who undergo to abdomino perineal resection (A.Pe.R.) of the anorectum for lower rectal cancer. In selected cases, laparoscopically assisted TAR can significantly improve body image preservation and aesthetic results. A 33-year-old woman affected by lower rectal cancer was submitted to laparoscopic-assisted A.Pe.R and TAR with simultaneous bilateral graciloplasty; a suprapubic median mini-access was adopted to fully mobilize the mesorectum in absence of pneumoperitoneum. A subcutaneous pulse generator and special electrodes were also implanted to chronically electrostimulate the graciloplasty. In spite of postoperative bleeding which required a blood transfusion, postoperative outcome was satisfactory; electrostimulation was started on the 10th postoperative (p.o.) day and the patient was discharged on the 17th p.o. day. Two months after TAR, level II continence (N.S. Williams Scale) was achieved. In selected cases, laparoscopically assisted A.Pe.R. and TAR can be safely adopted to preserve body image and quality of life, avoiding at the same time a large abdominal approach and a "permanent" abdominal colostomy. PMID- 9373298 TI - First trimester of pregnancy laparoscopic procedures. AB - Laparoscopic procedures are being performed during pregnancy with increasing frequency; however, few first-trimester operations have been published. Two first trimester procedures are here reported, both performed with uneventful recoveries. PMID- 9373299 TI - Hand-assisted laparoscopic vertical banded gastroplasty. Initial report. AB - Laparoscopic approaches to surgery for morbid obesity offer to reduce the morbidity associated with conventional weight reduction surgery. This paper describes a hand-assisted laparoscopic technique for vertical banded gastroplasty, a method which shortens and simplifies the laparoscopic approach to this established open surgical procedure. PMID- 9373297 TI - Minimally invasive surgical biopsy confirms PET findings in esophageal cancer. AB - This report describes our initial experience using positron emission tomography (PET) scanning in esophageal cancer patients. In two patients PET identified distant metastatic disease missed by conventional staging. Laparoscopic biopsy provided histological confirmation of metastases. In the third patient, locoregional lymph nodes were identified by PET and confirmed by surgical staging. In this preliminary report, PET appears to be a promising new noninvasive modality for staging patients with esophageal cancer. PMID- 9373300 TI - Laparoscopic infrared imaging. AB - A system was developed to determine the potential role of infrared imaging as a tool for localizing anatomic structures and assessing tissue viability during laparoscopic surgical procedures. A camera system sensitive to emitted energy in the midinfrared range (3-5 micron) was incorporated into a two-channel visible laparoscope. Laparoscopic cholecystectomy, dissection of the ureter, and assessment of bowel perfusion were performed in a porcine model with the aid of this infrared imaging system. Inexperienced laparoscopists were asked to localize and differentiate structures before dissection using the visible system and then using the infrared system. Assessment of bowel perfusion was also conducted using each system. Infrared imaging proved to be useful in differentiating between blood vessels and other anatomic structures. Differentiation of the cystic duct and arteries and transperitoneal localization of the ureter were successful in all instances using the infrared system when use of the visible system had failed. This system also permitted assessment of bowel perfusion during laparoscopic occlusion of mesenteric vessels. These initial studies demonstrate that infrared imaging may improve the differentiation and localization of anatomic structures and allow assessment of physiologic parameters such as perfusion not previously attainable with visible laparoscopic techniques. It may thus potentially be a powerful adjunct to laparoscopic surgery. PMID- 9373301 TI - Tumor dissemination during laparoscopic cholecystectomy for gallbladder carcinoma. PMID- 9373302 TI - Laparoscopic and conventional closure of perforated peptic ulcer. PMID- 9373303 TI - The author replies PMID- 9373304 TI - Laparoscopic vs open hernioplasty. Which open technique for a correct comparison of outcomes? PMID- 9373305 TI - The author replies PMID- 9373306 TI - Immunotherapy of cancer by peptide-based vaccines for the induction of tumor specific T cell immunity. AB - Recent progress in defining the molecular nature of antigens and in finding ways to manipulate T cell-mediated immune responses may provide new modalities for cancer treatment. In this report, we review preclinical studies as well as the first clinical trials with vaccination strategies aiming at the induction of anti tumor immunity. In particular, we focus on the development of a vaccine against human papillomavirus-induced cervical carcinoma. PMID- 9373307 TI - An overview of the 1996 Keystone meeting. Exploring and exploiting antibody and Ig superfamily combining sites. PMID- 9373309 TI - Proteolytic cleavage of MHC class I by complement C1-esterases--an overlooked mechanism? AB - The complement C1-esterases have been shown to cleave the MHC class I molecules, which are important participants in the activation of T lymphocytes, between the alpha 2- and the alpha 3-domain of the heavy chain. The possible involvement of the C1-esterases in the regulation of peripheral self-tolerance is discussed. It is hypothesized that the C1-esterase-mediated cleavage of the MHC class I molecules either induces: a soluble fragment of the outer two domains of the MHC class I molecule, in association with beta 2-microglobulin, to bind to the T cell receptors and prevent the cells from being activated, or produces a change in the exposure of the alpha 3-domain that remain on the cell surface, acting as mediator of a 'veto signal' that prevents these cells from being activated. PMID- 9373308 TI - Antibody-targeted superantigens in cancer immunotherapy. PMID- 9373310 TI - Affinity improvement of single antibody VH domains: residues in all three hypervariable regions affect antigen binding. AB - BACKGROUND: Through antibody engineering, immunoglobulins can be tailored for their particular application. In this respect, small recognition units are desired for the targeting of antigens in obstructed locations like solid tumors. OBJECTIVES: To design efficient, minimum size recognition units, heavy chain variable regions (VH) had previously been modified for the use as antigen specific, single domain antibody fragments. To develop a rational approach to improve affinity, antigen binding is investigated here by analysing the effect of randomisations of CDR1 and 2 residues in VH domains specific for hapten and protein ligands. STUDY DESIGN: Randomised repertoires were displayed on phage and affinity selected to improve and analyse antigen binding. Affinities of newly selected VH domains were determined in their soluble format to assess the role of modified residues in binding. RESULTS: In four of five randomisation experiments, a new VH with an improved antigen affinity compared to the primary VH was selected. Dissociation constants decreased from 160 nM to 25 nM or 47 nM (CDR1 or CDR2 randomisation of an anti-Ox VH), from 300 nM to 31 nM (CDR2 randomisation of an anti-NIP VH) and from 3.1 microM to 1.6 microM (CDR2 randomisation of an anti lysozyme VH). CONCLUSIONS: Thus the affinity of VH domains can be improved after site specific, secondary randomisations in CDR1 and CDR2, phage display and antigen selection. As differences in the CDR3 sequences had formed the only difference between the primary VH domains used in this study, the effect of CDR1 and CDR2 mutations of affinity is consistent with a participation of all three CDRs in antigen binding by single VH domains. PMID- 9373311 TI - Generation of a panel of related human scFv antibodies with high affinities for human CEA. AB - BACKGROUND: A human single chain Fv (scFv) specific for human carcinoembryonic antigen (CEA) has been isolated from a 2.0 x 10(9) phage display library from unimmunised human donors. The dissociation constant of the scFv has been measured by surface plasmon resonance (SPR) and found to be 7.7 x 10(-9) M, with an off rate component of 6.2 x 10(-3) s-1. In order to investigate directly whether increased affinity leads to improved targeting of CEA-positive tumours, this scFv has been affinity matured by both targeted mutagenesis of the CDRs of heavy and light chains, and by light chain shuffling. STUDY DESIGN: A partial randomisation scheme, biased towards amino acids commonly found as somatic mutations of germline antibody sequences, was used for directed diversification of VH and VL CDR3s. Diversification of the entire VL region was also introduced by light chain shuffling of the parental anti-CEA scFv. Selection of the mutagenised repertoires was carried out to enrich for antibodies with a reduced koff. RESULTS: Sequencing the selected clones identified a number of amino acid changes in the VH CDR3, one of which gave a four-fold reduction in koff. Stringent selection of the light chain shuffled library resulted in several clones with a two- to three-fold reduction in koff. It has been possible to combine the selected changes from both mutagenesis approaches by using the mutagenised heavy chain and a light chain derived by shuffling to give a human scFv with a dissociation constant for human CEA of 6.0 x 10(-10) M. CONCLUSION: A panel of human anti-CEA scFvs has been generated with differing dissociation constants for antigen, which will allow the correlation between tumour targeting efficiency in relation to binding affinity to be assessed directly. The scFv panel will be valuable in the optimisation of human antibodies for immunotherapy. PMID- 9373312 TI - Improving the copy numbers of antibody fragments expressed on the major coat protein of bacteriophage M13. AB - BACKGROUND: Antibody fragments have been expressed on the major coat protein of filamentous phage using a gene VIII expression system, but with low copy numbers (averaging 0.2 Fab/phage). OBJECTIVES: As a general strategy to increase copy number, the phage vector was optimized by site directed mutagenesis. STUDY DESIGN: One mutation was the introduction of a random six amino acid tether between the heavy chain and pseudo gene VIII to form a phage library. The other mutation was the removal of two cysteine residues which form a disulfide bond between the heavy and light chains. An assay was developed to measure Fab concentrations and used to calculate the average number of copies displayed on phage. RESULTS: Phage libraries containing random tethers were panned, and clones containing a proline rich motif were extracted. Removing the interchain disulfide had a greater effect on copy number and soluble Fab concentrations in the periplasmic space of the bacterial cultures. CONCLUSION: A tenfold increase in the copy number was achieved using the optimized vector. Incorporation of these vector mutations may be a general strategy for optimizing Fab display on the major coat protein of bacteriophage M13. PMID- 9373313 TI - In vitro selection of a high affinity antibody to oestradiol using a phage display human antibody library. AB - We have isolated a monoclonal antibody binding to oestradiol with high affinity (3.7 nM), and exhibiting a better than 1000-fold selectivity in binding to other steroids. A high affinity antibody with good specificity is essential for the accurate determination of circulating oestradiol levels. To date, conventional hybridoma technology has not yielded a reagent of sufficiently high affinity and specificity for this ligand. The aim of this study was to investigate whether such a reagent was accessible through the engineering of antibodies on the surface of filamentous phage. Antibodies were isolated from a large repertoire of single chain Fv fragments (scFv) derived from non-immunised human donors, with selection and screening procedures biased to favour those binding to free oestradiol. This resulted in an antibody with nanomolar affinity for oestradiol, while affinities for related steroids are in the micromolar range. The relative lack of reactivity for steroids substituted at either end of the molecule suggests that this antibody is unique among anti-steroid monoclonal antibodies in lacking a 'blind-spot'. Our results demonstrate that phage display can provide solutions to problems that have so far proved intractable using conventional hybridoma technology. PMID- 9373314 TI - Cloning, expression and functional activities of a single chain antibody fragment directed to fusion protein of respiratory syncytial virus. AB - BACKGROUND: HNK20 is a murine IgA which is currently being investigated in clinical trials against respiratory syncytial virus (RSV) infections in infants and young children. OBJECTIVE: To produce a single chain antibody fragment (scFv) from HNK20 hybridoma cells and assess its functional activities in vitro and in vivo (mouse model). STUDY DESIGN: The V regions of heavy and light chains were cloned and linked by a sequence encoding for (Gly4 Ser)3 and expressed in Escherichia coli. RESULTS: Over 100 mg/l of the HNK20-scFv was produced in shake flasks after induction with isopropyl (beta-D-thiogalactopyranoside (IPTG). ScFv was purified under native conditions on a Ni2+ affinity column and migrated as a single band of 34 kDa on sodium dodecyl sulfate (SDS)-gels. ScFv demonstrated similar affinity as its parent IgA molecule, neutralized RSV in vitro and significantly reduced RSV titers in lungs of mice when administered intranasally shortly before or a day after RSV challenge. CONCLUSION: It is possible that this scFv or its derivatives, when applied by intranasal or pulmonary route, will be useful for treatment of RSV infections in infants and young children. PMID- 9373315 TI - Antigen binding and cytotoxic properties of a recombinant immunotoxin incorporating the lytic peptide, melittin. AB - BACKGROUND: The majority of immunotoxins studied to date incorporate toxins that act in the cytosol and thus need to be endocytosed by the target cell. An alternative strategy for immunotoxin development is the use of membrane active toxins, such as the pore-forming proteins. Melittin, a 26 amino acid cytolytic peptide from bee venom, is such a protein. OBJECTIVES: We report here the construction, production and functional analysis of a recombinant immunotoxin obtained by fusion of genes which encode an antibody fragment (scFv) with an oligonucleotide encoding melittin. STUDY DESIGN: The antibody fragment was derived from a murine monoclonal antibody, K121, which recognises a specific epitope (KMA) expressed on the surface of human kappa myeloma and lymphoma cells, and on human free kappa Bence Jones protein (BJP). Melittin is a 26-amino acid, membrane-lytic peptide which is a major component of bee venom. The scFv of K121 was constructed by PCR to link VH and VL genes via an oligonucleotide which encodes a flexible, hydrophilic peptide. An oligonucleotide encoding melittin and the peptide marker sequence FLAG was fused to the scFv construct using a similar linker peptide. The gene construct (scFv-mel) was inserted into the secretion vector pPOW and expressed in Escherichia coli (TOPP2). RESULTS: Expression of the recombinant scFv-mel gene and purification of the protein product was monitored by Western blot analysis. Following purification by anti-FLAG affinity chromatography, the recombinant immunotoxin (scFv-mel) was assessed for antigen binding and for cytotoxic activity by flow cytometry using antigen-expressing and non-expressing cell targets. The scFv-mel was found to exhibit binding and killing properties consistent with the specificity of the original K121 antibody. Moreover, the cytolytic activity of the scFv-mel was significantly greater on a molar basis than that of native melittin alone. CONCLUSION: The data presented here constitute the first report of a melittin-based recombinant immunotoxin and demonstrate that such a membrane active immunotoxin can be synthesised in a bacterial expression. Linking of melittin to an antibody fragment overcame the non-specific toxicity of melittin as the recombinant immunotoxin exhibited specific toxicity towards antigen-bearing target cells. The observation that the immunotoxin exhibited enhanced cytotoxic activity over the free toxin indicates the potential of this approach for the development of an effective therapeutic agent. PMID- 9373316 TI - Gene vaccines. AB - A most surprising finding was that naked DNA when injected into animal tissue is taken up and expressed by cells with great efficiency. The DNA is given as a plasmid which includes a promoter and an enhancer. When inoculated, it is not stably integrated within the chromosomal DNA, but persists as extrachromosomal nuclear episomes. Both purified DNA and RNA have been shown to be expressed in somatic cells. It is now well established that injection of DNA by many routes is expressed in vivo and the proteins immunogenic. DNA vaccines appear to induce efficient and complete immune responses. The immunizations produce long-term humoral and cellular responses, qualitatively similar to live attenuated vaccines but without the safety hazards of infectious agents. These findings will have important implications for the continued development of human vaccines. PMID- 9373317 TI - Engineering of doubly antigenized immunoglobulins expressing T and B viral epitopes. AB - BACKGROUND: Concomitant with the advent of molecular biology techniques and the ability of immunoglobulins (Ig) to recognize proteins, carbohydrates, lipopeptides and nucleic acids, vaccinologists have taken advantage to develop a variety of prophylactic and therapeutic vaccine prototypes. Presentation of epitopes to the immune system by Ig molecules as a carrier platform offers several advantages: (i) long exposure of the antigen to antigen processing cells (APCs) by virtue of their long half life, (ii) lack of the immune response to self Ig, focusing the immune response to protective epitopes rather than irrelevant epitopes, (iii) it takes advantage of the properties of Fc fragment of various isotypes like crossing the placenta (IgG) or homing in epithelia (IgA), and (iv) targeting various antigens by virtue of their binding specificity. OBJECTIVES: This study was aimed to genetically and enzymatically engineer immunoglobulins (Igs) able to express and to deliver concomitantly immunodominant T and B viral epitopes. STUDY DESIGN: Using a genetic engineering approach we replaced the complementary determining region 3 (CDR3) and complementary determining region 2 (CDR2) of an anti-arsonate 91A3 mAb with the immunodominant HA110-120 T cell epitope and HA150-159 B cell epitope of hemagglutinin (HA) of influenza A/PR8 virus, respectively. The second doubly antigenized Ig (Ig-HA-Gal B) was constructed on an Ig in which CDR3 was replaced with HA110-120 T cell epitope while the HA150-159 B cell epitope was enzymatically assembled through an imidic bond on the galactose (Gal) residues of the carbohydrate moiety. RESULTS AND CONCLUSIONS: Both genetically and genetically/enzymatically doubly antigenized Ig constructs (dAIg) were properly folded and they were able to activate peptide-specific T cells and to elicit anti-viral antibody response in mice. This demonstrates that the CDR loops as well as carbohydrate moieties of immunoglobulins represent permissive sites for grafting foreign epitopes without altering the structural integrity of immunoglobulins and the immunogenicity of the viral peptides. PMID- 9373318 TI - Separation of E. coli expressing functional cell-wall bound antibody fragments by FACS. AB - BACKGROUND: The rapid development of recombinant antibody technology in the last few years has facilitated the generation of antibody libraries in bacteria. Recombinant antibodies against various antigens have been selected from these libraries by presenting each antibody on the surface of a phagemid particle that contains the antibody's gene. An alternative screening system is the display of antibody fragments on bacteria. A major advantage is the possibility to select single cells directly from a large number of bacteria by using fluorescently labeled antigens and fluorescence assisted cell sorting (FACS). OBJECTIVES: pAP is an expression vector for the bacterial display of antibody fragments. E. coli transformed with pAP express a single chain antibody (scFv) fused to the peptidoglycan-associated-lipoprotein (PAL). This fusion protein binds strongly to the cell wall. To employ this system for screening, we have investigated the possibility of selecting antigen-specific clones by FACS. STUDY DESIGN AND RESULTS: Several DNA fragments coding for various scFvs were inserted into the pAP expression vector. E. coli were transformed with these plasmids and immunostained with fluorescent antigens under given conditions. We were able to select stained E. coli expressing a specific scFv from unstained E. coli expressing a non-binding scFv by FACS. The specific selection of the bacteria was demonstrated by amplifying their genes by PCR. CONCLUSIONS: Conditions are described for separating E. coli containing scFv bound to their cell wall by FACS using fluorescently labeled antigens. These studies provide a basis for screening libraries of scFv antibodies. PMID- 9373319 TI - Immunoreactivity of allergen (Bet v 1) conjugated to crystalline bacterial cell surface layers (S-layers). AB - BACKGROUND: Crystalline cell surface layers (S-layers) from Gram-positive eubacteria had been demonstrated as carrier/adjuvants for chemically synthesized tumor-associated oligosaccharide haptens and capsular polysaccharide antigens of Streptococcus pneumoniae strains. OBJECTIVES: The applicability of S-layers as vaccine carrier for treatment of Type I allergy was investigated. STUDY DESIGN: Native or cross-linked S-layer self-assembly products and cell wall preparations from Bacillus sphaericus CCM 2177 and Thermoanaerobacter thermohydrosulfuricus L111-69 and L110-69 were used for immobilization of recombinant major birch pollen allergen Bet v 1. RESULTS AND CONCLUSIONS: Depending on the carrier used, amounts of approximately 20-40 micrograms allergen per mg conjugate could be immobilized. By application of L-glutamic acid dimethyl ester as a spacer, this value could be increased approximately 10-fold. The functionality of the rBet v 1 conjugates was assessed in immunological systems. (i) The presence of intact B cell epitopes was demonstrated in inhibition experiments using human Bet v 1 specific IgE. (ii) The rBet v 1-S-layer conjugates were immunogenic in mice. (iii) The proliferation of rBet v 1-specific T-cell clones suggested that the peptides created by processing of immobilized Bet v 1 were similar to those derived from natural allergen. (iv) Stimulation of human allergen-specific TH2 lymphocytes with S-layer-conjugated Bet v 1 led to a modulation of the cytokine production pattern from TH2 to TH0/TH1. This study indicates that S-layers may be suitable carriers for few immunotherapeutical vaccines for Type 1 hypersensitivity. PMID- 9373320 TI - Epitope mapping of a C5a neutralizing mAb using a combined approach of phage display, synthetic peptides and site-directed mutagenesis. AB - BACKGROUND: The anaphylatoxin C5a is a powerful proinflammatory protein generated on activation of the complement system. Recently, we described an anti-hC5a neoepitope specific mAb, mAb 2925, which was raised against the nonapeptide ISHKDMQLG (C5a-(65-73). This mAb is unique in that it recognizes both hC5a and hC5adesArg, even when it is denatured. It inhibits binding of [125I]C5a to its receptor on Bt2-cAMP differentiated U937 cells. OBJECTIVES: To define the epitope of mAb 2925, we used a combined approach of a bacteriophage random octapeptide library, synthetic peptides and site-directed mutagenesis. STUDY DESIGN: First a phage peptide library was screened with the anti C5a mAb 2925. Then synthetic peptides were synthesized with respect to the sequence information yielded from the phage approach, and used for binding studies. Site-directed mutagenesis was performed to confirm the results from the mapping experiments. RESULTS AND CONCLUSION: Most phages selected by biotinylated Fab 2925 displayed sequences on the minor coat protein which correspond to residues within the C-terminus of human C5a. A first consensus motif comprised amino acids His-Lys or His-Arg, which allowed us to define position 67 and 68 as part of the epitope. A second consensus motif was selected, comprising Arg/Lys-Trp-Trp. This motif did not match any residues within the C5a C-terminus. However, when expressed together with the consensus motif His-Arg, as in HRWWXXXX or in HRXKWWXX, binding of these peptides to Fab 2925 increased as compared to peptides expressing the His-Arg motif only. Thus, the Arg/Lys-Trp-Trp motif serves to stabilize the binding of His-Arg to mAb 2925. Synthetic peptide studies revealed further N-terminal residues Ile65 and Ser66 as part of the epitope. A C5a mutant with an exchange Lys68Glu (C5aGlu68) confirmed the participation of Lys68 as a contact residue within the epitope of mAb 2925. Hence, the epitope recognized by mAb 2925 is linear and comprises residues Ile65, Ser66, His67, and Lys68. Thus, we could demonstrate for the first time that a mAb inhibits C5a receptor binding through specific interaction with receptor binding residues of the ligand. PMID- 9373321 TI - Affinity maturation of recombinant antibodies using E. coli mutator cells. AB - BACKGROUND: Phage libraries can display repertoires of antibodies which are greater in number than the mammalian immune response. However, the selected antibodies often have low binding affinity to their target antigen or hapten (KD below 10(-6) M), which is characteristic of the primary immune repertoire. There is a need for procedures to mimic somatic hypermutation through antigen driven affinity maturation, thereby increasing the affinity of selected immunoglobulins. OBJECTIVE: To investigate the effectiveness of mutation and affinity selection of recombinant antibody genes with mutator E. coli cells, incorporating phage display strategies. STUDY DESIGN: Unique human scFvs were selected from a naive Fd-phage library. These genes were mutated by propagation in mutD5 mutator E. coli cells (mutD5-FIT) which were competent for Fd (M13) based phagemid transfections and generated point mutations (transversions and transitions) in the scFv genes. Individual phage-displayed scFvs were affinity selected from the mutation library and were assayed as soluble scFvs by ELISA and BIAcore for binding to antigen. RESULTS: The in vivo mutation of phage-displayed scFvs in E. coli mutD5-FIT, combined with affinity selection against antigen, produced scFv molecules with improved binding activity. The point mutations which resulted in single amino acid substitutions frequently produced ten fold increases in apparent binding affinity. Structural comparisons revealed that these point mutations were in framework regions (adjacent to the CDRs) and within the CDRs. In one case the apparent affinity of an anti-glycophorin scFv after mutation in the VL framework region close to CDR3 increased by 10(3). However, this increase in apparent affinity was accompanied by an increased propensity to dimerise and form aggregates. CONCLUSIONS: A strategy for the rapid affinity maturation of scFv and Fab antibody fragments has been developed which utilises mutator strains of E. coli and incorporates phage display of antibody repertoires (libraries). PMID- 9373322 TI - pDAP2: a vector for construction of alkaline phosphatase fusion-proteins. AB - BACKGROUND: Expression of enzymatically active protein fusions in Escherichia coli could facilitate the analysis of proteins and even replace some reagents frequently used in immunology such as chemically produced antibody-enzyme conjugates. For this purpose there is up to now no system of general utility available. OBJECTIVES: The vector pDAP2 has been designed for simplified fusion of single-chain Fv fragments to the N-terminus of E. coli alkaline phosphatase. The resulting immunoconjugates can be produced by expression in E. coli and purified in a single step via metal affinity chromatography. STUDY DESIGN: Several different single-chain Fv genes as well as peptide coding oligonucleotides have been cloned into pDAP2 and tested for expression levels, purification properties and usefulness in ELISA and immunowestern blotting. RESULTS: The fusion proteins from pDAP2 can be prepared at levels of several milligrams per liter culture from the periplasma of the cells. The proteins work well in different immunoassay formats such as ELISA or western blotting. CONCLUSION: pDAP2 is compatible to phage display vectors such as pHEN1, pCOCK and the pCANTAB-series (Pharmacia, Sweden). Genes of single-chain antibody fragments can be simply swapped from these vectors into pDAP2. Furthermore, we demonstrate that it is possible to produce alkaline phosphatase-active peptides with this vector by inserting synthetic coding oligonucleotides. This allows simple analysis of the binding properties of peptides and may have some advantages over other systems such as fusion to glutathione-S-transferase. PMID- 9373324 TI - Epitope mapping, V-region DNA sequence, and neutralizing Fab fragments of two monoclonal antibodies against the HIV-1 V3 loop. AB - BACKGROUND: Experimental evidence suggests that neutralizing antibodies could constitute an important factor in the control of AIDS progression and that the V3 loop of gp120 constitutes the main target for such purposes. We have previously developed two neutralizing murine monoclonal antibodies (Mabs) against the V3 region of the HIV-1 MN strain. OBJECTIVES: To characterize those Mabs in terms of fine specificity and DNA sequence of their V regions and to study if Fab fragments retain their neutralizing potential in vitro. STUDY DESIGN: A set of 12 mer alanine substituted peptides were employed for epitope mapping using two ELISA procedures: (1) indirect, with each peptide bound to polystyrene plates, and (2) competitive, with co-incubation of peptides and Mabs in solution. The V regions of both Mabs were PCR amplified from cDNA and their nucleotide sequences were determined. Finally, Fab fragments of Mab 10F10 were generated and their neutralizing capacity against the MN isolated was assessed. RESULTS: We first restricted the minimal length of the epitopes recognized by 2C4 and 10F10 to the 12-mer peptide KRIHIGPGRAFY. The core of the epitopes recognized by Mabs 2C4 and 10F10 were IHIGP-R and IHIG-R, respectively. While substitution of proline in position 7 completely abolished the binding of 2C4, it only reduced that of 10F10 by 50%. Finally, Fab fragments of Mab 10F10 were still able to neutralize the HIV 1 MN strain in vitro. CONCLUSION: This subtle distinction in the fine mapping of the epitope recognized by Mabs 2C4 and 10F10 should correspond to three amino acid differences that we found in the heavy chain V-regions. The Fab fragments of Mab 10F10 retained the neutralizing capacity. This indicates that HIV neutralization by anti V3 Mabs is an Fc independent process. PMID- 9373323 TI - T cell responses against mutant ras: a basis for novel cancer vaccines. PMID- 9373325 TI - Tumor localization of anti-CEA single-chain Fvs: improved targeting by non covalent dimers. AB - BACKGROUND: Genetic engineering can produce novel antibody fragments with improved properties for applications such as tumor targeting in vivo. OBJECTIVES: To produce stable monomeric (27 kDa) and dimeric (55 kDa) forms of a single-chain Fv (scFv) from the anti-carcinoembryonic antigen (anti-CEA) antibody T84.66, and assess the targeting and biodistribution properties in an animal model. STUDY DESIGN: ScFv were constructed with either a 28 or 14 amino acid connecting peptide and expressed by secretion from E. coli. Following affinity purification, proteins were characterized by gel electrophoresis and mass spectrometry. Binding properties were assessed by size exclusion HPLC after incubation with antigen, and affinities determined by surface plasmon resonance. The shorter linker favored formation of dimers (and higher multimers) which showed unusual stability. ScFv were radiolabeled with 125I for tumor targeting and biodistribution studies of monomeric or dimeric forms were conducted in athymic mice bearing LS174T human colorectal carcinoma xenografts. RESULTS: 125I-scFv monomers and dimers targeted exhibited rapid clearance kinetics in tumor-bearing mice. Nevertheless, the anti-CEA scFvs targeted very well to xenografts, leading to high tumor: normal organ ratios (greater than 20:1 at 24 h) for both forms. Tumor localization of the non-covalent dimers was much higher than monomers, reaching 10-15% injected dose per gram at 1 h. CONCLUSION: Non-covalent dimers of scFv (also known as diabodies) are stable, easy to produce and show excellent targeting as compared to monomeric scFv, probably due to increased mass and valency. PMID- 9373326 TI - Identification of epitope recognized by an anti-c-myc monoclonal antibody that cross-reacts with E. coli sigma factor using phage display libraries. AB - BACKGROUND: During the epitope mapping of monoclonal antibodies specific for myc proteins, two E. coli proteins cross-reactive with an anti-c-myc monoclonal antibody (MYC-X-5/1) were identified. One of the proteins is approximately 90 kDa and the other is over 150 kDa in apparent molecular mass. The molecular masses of these cross-reactive proteins suggested that they may be subunits of E. coli RNA polymerase. OBJECTIVES: We have investigated whether or not the proteins cross reactive with MYC-X-5/1 are subunits of E. coli RNA polymerase. In addition, we have attempted to determine the epitope of MYC-X-5/1. STUDY DESIGN: The reactivity of MYC-X-5/1 antibody was tested against highly purified E. coli RNA polymerase holo-enzyme preparations and the cell lysate made from E. coli carrying a multi-copy plasmid with an insert of the rpoD gene, the structural gene for the E. coli sigma subunit. The epitope of MYC-X-5/1 was determined by use of phage display of random peptide libraries. RESULTS: On immunoblotting assays, MYC-X-5/1 reacted with the 90-kDa protein in the E. coli RNA polymerase preparations and with the 90-kDa protein over-expressed in E. coli carrying the plasmid with the rpoD insert. In addition, we have deduced the epitope of the MYC X-5/1 antibody to be residues 235-245 of the human c-myc protein. A highly similar sequence to this was also identified in residues 62-72 of the sigma subunit of E. coli RNA polymerase. CONCLUSION: These data demonstrated that the 90-kDa protein cross-reactive with MYC-X-5/1 is the sigma subunit of E. coli RNA polymerase. Furthermore, this study shows that random peptide libraries displayed on filamentous phage are useful tools for epitope mapping and defining cross reactivities of monoclonal antibodies. PMID- 9373327 TI - In vitro and in vivo characterisation of a recombinant carboxypeptidase G2::anti CEA scFv fusion protein. AB - BACKGROUND: There is considerable interest in the specific targeting of therapeutic agents to cancer cells. Of particular promise is a technique known as Antibody-Directed Enzyme Prodrug Therapy (ADEPT). In this approach an enzyme is targeted to the tumour by its conjugation to a tumour specific-antibody tumour. After allowing sufficient time for the conjugate to localise at the tumour and clear from the circulatory system, a relatively non-toxic prodrug is administered. This prodrug is converted to a highly cytotoxic drug by the action of the targeted enzyme localised at the tumour site. OBJECTIVES: To construct gene fusions between the pseudomonad carboxypeptidase G2 (CPG2) gene and DNA encoding MFE-23 (an anti-carcinoembryonic antigen (CEA) single-chain Fv (scFv) molecule), derived from a phage display library. To overexpress the resultant gene fusions in Escherichia coli, and assess the in vitro and in vivo properties of the purified fusion proteins. STUDY DESIGN: To introduce unique cloning restriction sites into the 5'-end of the CPG2 gene by site-directed mutagenesis to facilitate fusion to the 3'-end of the gene encoding MFE-23 (constructs with or without a flexible (Gly4Ser)3 linker-encoding sequence were designed). To overexpress the resultant gene fusions under transcriptional control of the lac promoter and to direct the fusion proteins produced to the periplasmic space of E. coli through translational coupling to the pelB signal peptide. RESULTS: Biologically active recombinant CPG2::MFE-23 scFv fusion proteins were produced in E. coli and shown to possess enzyme and anti-CEA activity. Affinity chromatography followed by size exclusion gel filtration yielded approximately 0.7-1.4 mg/l from shake flask culture. The fusion protein in which the enzyme and antibody moieties were joined by a linker peptide was shown to be effectively localised in nude mice bearing human colon tumour xenografts, giving favourable tumour to blood ratios. CONCLUSION: MFE-23 scFv serves as an ideal candidate for the antibody arm of a bacterially expressed fusion protein with CPG2. The biological properties of this recombinant protein suggest that it may be employed for tumour specific prodrug activation. However, further assessment of its stability and pharmokinetics is required if genetic fusion is to be considered as an alternative to chemical conjugation. PMID- 9373328 TI - Meeting report from the 'Therapeutic Antibody Technology 95' meeting--not just 'another recombinant antibody meeting'. PMID- 9373329 TI - Intracellular antibodies (intrabodies) as research reagents and therapeutic molecules for gene therapy. PMID- 9373330 TI - Human monoclonal Fab fragments specific for viral antigens from combinatorial IgA libraries. AB - BACKGROUND: IgA constitutes the first line of immune defense, interacting with a variety of environmental antigens. Following infection with respiratory syncytial virus (RSV) individuals frequently exhibit elevated serum IgA titers specific for the virus. Previously combinatorial IgG libraries have successfully been used to clone such human antibody responses. OBJECTIVES: Here we evaluate the possibility of constructing combinatorial IgA libraries on the surface of filamentous phage to retrieve human viral-specific IgA Fab fragments. STUDY DESIGN: Bone marrow from an HIV-1 seropositive donor was used as RNA source to construct combinatorial IgA kappa and lambda libraries of approximately 10(7) clones. RESULTS: By affinity selection using an immobilized recombinant RSV FG protein, two unique IgA Fab fragments producing clones (AD5 and AD23) reactive with the selecting antigen were isolated. One of the Fab fragments was found to be specific for RSV F glycoprotein and bind with high apparent affinity (2 x 10(8) M 1). The other binds with lower affinity and exhibits cross-reactivity with other antigens. CONCLUSION: The strategy described, involving construction of combinatorial IgA libraries on the surface of filamentous phage, should be generally applicable to the investigation of both mucosal and systemic human IgA immune responses, and may become an important tool for evaluation of mucosal vaccine regimes. PMID- 9373331 TI - Antigen-specific activation of B cells in vitro after recruitment of T cell help with superantigen. AB - BACKGROUND: Human B cells can proliferate in vitro after stimulation with anti-Ig and via the CD40 molecule. Superantigens like SEA which bind to MHC class II antigens on, e.g. B cells can polyclonally activate T cells via interaction with their TcR. The activated T cell subsequently activates the B cells to proliferation and Ig-production. OBJECTIVES: To investigate whether superantigen could be used to direct polyclonal T cell help to human B cells stimulated by antigen in a restricted manner resulting in production of antigen-specific antibodies in vitro. STUDY DESIGN: Purified B cells were preincubated with the antigen in manners allowing crosslinking of surface-Ig. The antigen exposed B cells were then cultured together with autologous CD4+ helper T cells and in the presence of various concentrations of SEA. Antibody production was measured by ELISA after 7-12 days of culture. RESULTS: Antigen-specific activation of B cells could be obtained after stimulating the B cells with antigen or anti-surface-Ig antibodies in the presence of T helper cells and SEA. The degree of B cell activation (proliferation as well as antibody production) depended on the dose of antigen as well as on the dose of SEA used. Increased crosslinking of surface-Ig on antigen-specific B cells enhanced Ig production. Specific antibody production to a secondary recall antigen (tetanus toxoid) and to primary antigens (DNP and GM2) were obtained. The specific B cell response was dependent on contact between T and B cells. CONCLUSION: the results obtained demonstrate that the superantigen SEA can recruit T cell help to human B cells specifically stimulated by antigens, resulting in production of antigen reactive antibodies in vitro. PMID- 9373332 TI - Expression in Escherichia coli of soluble and M13 phage-displayed forms of a single-chain antibody fragment specific for digoxin: assessment in a novel drug immunoassay. AB - A high affinity anti-digoxin single-chain Fv antibody fragment (scFv) was cloned from the mouse 2C2 hybridoma cell line and was functionally expressed both in the Escherichia coli periplasm as a soluble molecule and at the surface of the filamentous M13 bacteriophage as a fusion protein with the gene III minor coat protein. The 2C2 scFv sequence significantly differs from that of all the other anti-digoxin antibodies previously described. The 2C2 scFv shares with its parental monoclonal antibody a high specificity for digoxin, a cross-reactivity with active digoxin metabolites, but none with inactive metabolites. M13 phages displaying the 2C2 scFv at their surface have a high apparent affinity constant for digoxin (6.6 x 10(8) M-1) and were directly used to set up a novel type of immunoenzymatic assay for monitoring digoxin in sera of patients treated for either congestive heart failure or cardiac arrythmias. We thus report for the first time that phages displaying scFv may constitute a large source of important new reagents in the field of immunodiagnosis. PMID- 9373333 TI - Monoclonal antibody against pIII of filamentous phage: an immunological tool to study pIII fusion protein expression in phage display systems. AB - A monoclonal antibody directed against the gene 3 product (pIII) of filamentous phage M13 was produced to study pIII-fusion protein expression in E. coli and its incorporation in the phage capsid. The protein was gel-purified from E. coli expression cultures harboring the genetic information of pIII under the control of an inducible lac promoter. To study pIII-fusion protein expression, phage display systems were applied in which either the whole pIII or the C-terminal half was used (McCafferty et al. (1990) Nature (London) 348, 552-554; Szardenings and Collins (1990) Gene 94, 1-7; Barbas and Lerner (1991) In: METHODS: Companion to METHODS in Enzymology, Combinatorial Immunoglobulin Libraries on the Surface of Phage (Phabs): Rapid Selection of Antigen-Specific Fabs, Vol. 2, Academic Press, Orlando, pp. 119-124). In all cases, the monoclonal antibody was able to detect the native and the recombinant protein in E. coli and on the phage tip using non-denaturing (ELISA) and denaturing (SDS-PAGE, immunoblot analysis) conditions. All selected pIII-specific monoclonal antibodies were found to be directed against epitopes within amino acids 198 to 406 of pIII, which is necessary for capsid incorporation and therefore included in all pIII-mediated phage display designs. PMID- 9373334 TI - Anti-microbial activity of human CAP18 peptides. AB - BACKGROUND: CAP18 derived from rabbit leukocytes is a 142-amino acid protein recently demonstrated to have Lipopolysaccharide (LPS) binding and anti-microbial activity. The C-terminal 37 amino acids of rabbit CAP18 (CAP18(106-142) comprise the LPS-binding and anti-microbial domain. The homologous domain of human CAP18 (huCAP18(104-140) was identified from the recently cloned human CAP18 cDNA. OBJECTIVES: To evaluate the antimicrobial activity of C-terminal peptides derived from human CAP18. STUDY DESIGN: Prepare synthetic human CAP18(104-140) and study anti-microbial activity versus various gram-negative and gram-positive bacteria. RESULTS: Synthetic human CAP18(104-140) has broad anti-microbial activity versus both gram-positive (IC50 = 2.5 micrograms/ml) and gram-negative bacteria (IC50 = 0.5-5 micrograms/ml). Susceptible strains include Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium. A 32-amino acid peptide lacking five amino acids from the C-terminus of CAP18(104-140) has higher activity. Unlike previously characterized anti microbial peptides derived from granulocyte proteins, CAP18(104-140) is active in serum. CONCLUSIONS: Human CAP18(104-140) or a derivative peptide may have therapeutic potential for bacterial sepsis. PMID- 9373336 TI - Green fluorescent protein: untapped potential in immunotechnology. AB - Many invertebrates produce bioluminescence using green-fluorescent proteins (GFPs) as energy-transfer acceptors. GFPs fluoresce in vivo upon receiving energy from either a luciferase-oxyluciferin excited-state complex or a Ca(2+)-activated photoprotein depending upon the organism. These highly fluorescent proteins are unique due to the chemical nature of their chromophore, which is comprised of modified amino acid residues within the polypeptide chain. Recently GFP was sequenced and cloned. GFP, GFP mutants or related proteins with altered spectra will have widespread use as a markers of gene expression and as a protein tags in cell culture and in multicellular organisms. Many of the uses of fluorescent labeled proteins or antibodies in immunotechnology will be improved by the use of GFP. Many new applications were discussed at a recent international symposium [1]. PMID- 9373335 TI - In vitro and in vivo characterization of a human anti-c-erbB-2 single-chain Fv isolated from a filamentous phage antibody library. AB - BACKGROUND: Antibody-based reagents have failed to live up to their anticipated role as highly specific targeting agents for cancer therapy. Targeting with human single-chain Fv (sFv) molecules may overcome some of the limitations of murine IgG, but are difficult to produce with conventional hybridoma technology. Alternatively, phage display of antibody gene repertoires can be used to produce human sFv. OBJECTIVES: To isolate and characterize human single chain Fvs which bind to c-erbB-2, an oncogene product overexpressed by 30-50% of breast carcinomas and other adenocarcinomas. STUDY DESIGN: A non-immune human single chain Fv phage antibody library was selected on human c-erbB extracellular domain and sFv characterized with respect to affinity, binding kinetics, and in vivo pharmacokinetics in tumor-bearing scid mice. RESULTS: A human single-chain Fv (C6.5) was isolated which binds specifically to c-erbB-2. C6.5 is entirely human in sequence, expresses at high level as native protein in E. coli, and is easily purified in high yield in two steps. C6.5 binds to immobilized c-erbB-2 extracellular domain with a Kd of 1.6 x 10(-8) M and to c-erbB-2 on SK-OV-3 cells with a Kd of 2.0 x 10(-8) M, an affinity that is similar to sFv produced against the same antigen from hybridomas. Biodistribution studies demonstrate 1.47% injected dose/g tumor 24 h after injection of 125I-C6.5 into scid mice bearing SK OV-3 tumors. Tumor:normal organ ratios range from 8.9:1 for kidney to 283:1 for muscle. CONCLUSIONS: These results are the first in vivo biodistribution studies using an sFv isolated from a non-immune human repertoire and confirm the specificity of sFv produced in this manner. The use of phage display to produce C6.5 mutants with higher affinity and slower k(off) would permit rigorous evaluation of the role of antibody affinity and binding kinetics in tumor targeting, and could result in the production of a therapeutically useful targeting protein for radioimmunotherapy and other applications. PMID- 9373337 TI - Phage display. AB - Phage display is a powerful method for the selection and evolution of proteins and peptides. Applications include the generation of potent and novel antibodies, the in vitro improvement of protein affinity and function, epitope discovery, the development of leads for vaccine research and the identification of interacting proteins using cDNA libraries. PMID- 9373338 TI - An IgG3-IL2 fusion protein activates complement, binds Fc gamma RI, generates LAK activity and shows enhanced binding to the high affinity IL-2R. AB - The therapeutic value of Interleukin 2 (IL-2) is limited by its short half life and systemic toxicity. One approach to overcoming these problems is to fuse this protein to an antibody, a protein with a long half life and the ability to target a unique antigen within the body. To examine the biochemical properties of such a molecule a fusion protein was constructed linking the N-terminus of human IL-2 to the C-terminus of IgG3. A similar fusion between IgG1 and IL-2 has previously been shown to bind antigen, generate antibody-dependent cellular cytotoxicity (ADCC) and stimulate T cell proliferation and cytotoxicity. We now extend these studies and show that the fusion protein, termed IgG3-IL2, is appropriately N glycosylated within the IgG3 CH2 domain, binds the human high affinity Fc receptor (Fc gamma RI) with an affinity slightly lower than that of IgG3, and is able to activate complement via the classical pathway to lyse antigen coated sheep red blood cells (SRBC). When used to stimulate the proliferation of the IL 2 dependent cell line CTLL-2, IgG3-IL2 has a specific activity slightly lower than that of human recombinant IL-2 (hrIL-2). In marked contrast, when comparable unit concentrations, as defined by the standard CTLL-2 proliferation assay, are used to stimulate human peripheral blood lymphocytes (PBL), IgG3-IL2 generates significantly greater lymphokine activated killer (LAK) cell cytotoxicity than does hrIL-2. Competition studies show that IgG3-IL2 binds the intermediate affinity form of the IL-2 receptor (IL-2R), consisting of the beta and gamma subunits, with an affinity slightly less than that of hrIL-2. In contrast, IgG3 IL2 shows a greater affinity than hrIL-2 for the high affinity IL-2R, consisting of alpha, beta and gamma subunits. Our studies show that the IgG3-IL2 fusion protein possesses a combination of the biological properties of IgG3 and IL-2 including antigen binding, complement activation, Fc gamma RI binding, IL-2R binding and stimulation of both proliferation and LAK activity. This combination of activities may allow IgG3-IL2 to target humoral and cell-mediated immune activation to the site of an antigen of interest or target an antigen to IL-2R bearing cells or organs. PMID- 9373339 TI - Production of active anti-CD6 mouse/human chimeric antibodies in the milk of transgenic mice. AB - The expression of chimeric genes in the mammary gland of transgenic farm animals has become an alternative for the large-scale production of recombinant proteins and for the modification of milk composition. In this paper, we show that a mouse/human chimeric antibody against the human CD6 leukocyte antigen can be assembled and correctly folded by the mammary gland, and secreted to milk, where it maintains its specificity. The base sequences encoding for the heavy and light chain variable regions of the anti-CD6 mouse monoclonal antibody IOR-T1 were cloned by the polymerase chain reaction from hybridoma cDNA, coupled to human heavy and light chain constant region genes, and inserted in a vector containing the 5' regulatory region of the rabbit whey acidic protein gene. Transgenic mice were produced by conventional pronuclei microinjection techniques. Integration and transgene copy number were determined by Southern blot. Assembled human immunoglobulin was detected in milk using a sandwich ELISA. Expression levels of chimeric antibodies in milk were determined to be around 400 micrograms/ml by Western blot, using CHO-derived chimeric IOR-T1 antibodies as reference. The chimeric antibodies produced in milk recognized human peripheral blood T lymphocytes by indirect immunofluorescence, with the classical patch-like pattern of IOR-T1. PMID- 9373340 TI - Isolation and characterization of allergen-binding cells from normal and allergic donors. AB - BACKGROUND: Flow cytometry of the immune system so far has been limited to the analysis of subpopulations according to lineage markers. The cells involved in a particular immune response could not be assayed due to their low frequency. Here we show the potential of antigen-specific high gradient magnetic cell sorting to enrich cells for visualisation in multiparameter cytometry, functional studies and immortalization. OBJECTIVES: The aim of this study was the development of an efficient technology for staining and isolation of antigen-binding cells from human peripheral blood. In particular, allergen-specific cells from normal and allergic donors should be analysed and compared to develop a cellular diagnosis of allergy. STUDY DESIGN: The rare antigen-specific cells were sorted by high gradient magnetic cell sorting with MACS. Haptenized phospholipase A2 (PLA2), the major allergen of bee venom, or haptenized ParoI, the major allergenic component of Parietaria officinalis, were used as antigens. The cells from normal and allergic donors, binding to the allergen were characterized phenotypically by immuno-fluorescence. Allergen-specific B-cells were immortalized by EBV transformation. RESULTS AND CONCLUSION: Allergen-specific cells can be enriched from blood of both allergic and normal donors to purities of up to 75%, by high gradient magnetic cell sorting. The specificity of labelling with allergen was confirmed by establishing allergen-specific EBV-transformed B-cell lines from the sorted cells. Clear differences exist in the cellular composition of allergen binding cells from normal compared to allergic donors. In normal donors the allergen-binding cells are B-cells expressing CD19 and CD21. In allergic donors, in addition to allergen-binding B-cells, occurring in about equal absolute numbers as in normal donors, basophilic granulocytes are labeled by allergen. These cells express CD38, CD9 and CD25 on their surface, and stain for IgE. PMID- 9373341 TI - Magnetofluorescent liposomes for increased sensitivity of immunofluorescence. AB - BACKGROUND: Immunofluorescence and immunomagnetism are important technologies for analysis and sorting of cells according to specific marker molecules. Due to the limited sensitivity at least several thousands of antigens per cell are required for optical detection. Molecules expressed at low copy numbers cannot be analysed, although they may be of considerable functional importance. OBJECTIVES: Development of a magnetic and fluorescent staining reagent for analysis and sorting of cells according to antigens expressed at low number. To this end, uniformly sized, antibody-conjugated liposomes loaded with large amounts of dye molecules and small magnetic particles were generated. STUDY DESIGN: A method for the preparation of homogeneously sized large unilamellar liposomes which contain carboxyfluorescein, magnetic particles and surface-bound antibodies had to be developed. These liposomes were then tested for their ability to enhance immunofluorescence compared to conventional staining in a model system and by staining of CD25 on resting B and T cells. RESULTS AND CONCLUSION: Large unilamellar liposomes, homogeneous in size and loaded with fluorescein and magnetic beads can be prepared by combining membrane extrusion and magnetic filtration. Hapten-specific antibodies conjugated to their surface make them a universal tool for immunofluorescence. With such liposomes, intensity of fluorescent staining can be increased 100-1000-fold without increased background fluorescence, compared to conventional fluorochrome-conjugated antibodies. Due to the simultaneous magnetic labelling, stained cells can easily be isolated by MACS. The magnetofluorescent liposomes proved to be useful for improvement of sensitivity of detection and physical separation in general and to visualize and sort cells according to antigens expressed at low levels. The high affinity IL2 receptor CD25 is expressed in low copy number on a significant fraction of resting B and T lymphocytes in human peripheral blood, as can be shown exclusively by the magnetofluorescent liposomes. PMID- 9373344 TI - CD59: its role in complement regulation and potential for therapeutic use. AB - CD59 regulates complement activation cascade at the final step, inhibiting formation of membrane attack complex (MAC). This protein, being anchored to the cell membrane via glycosyl phosphatidyl inositol (GPI), is expressed ubiquitously on cells which are in contact with body fluids containing components. Recently, MAC formation has been reported to play an important role in pathogenesis of inflammatory diseases such as ischemia or autoimmune diseases. In this review, we describe the structure and biological activities of CD59, the pathogenic role of MAC formation, and discuss application of soluble molecules of CD59 for therapeutic use. PMID- 9373342 TI - Bifunctional fusion proteins consisting of a single-chain antibody and an engineered lanthanide-binding protein. AB - The combination of an antibody fragment with a lanthanide chelating protein has desirable characteristics for fluorescence-based immunoassays and tumor radioimmunotherapy. As a model for this design, a fusion protein consisting of a single-chain antibody linked to an engineered version of oncomodulin, a protein with two Ca(2+)-binding motifs (the CD and EF loops), was produced by secretion from Escherichia coli in good yield. The single-chain antibody was specific for a Salmonella O-polysaccharide. The CD loop of oncomodulin had been redesigned to bind lanthanide ions with high affinity. The fusion protein was shown to have antigen-binding activity that was comparable to that of the unfused single-chain antibody, to bind Tb3+ with very high affinity and to give strong, sensitized Tb3+ luminescence via excitation of the tryptophan residue in the CD loop. A second fusion protein containing a 30-residue helix-loop-helix motif as the lanthanide-binding component was also prepared, but showed considerably lower solubility. Competition for Tb3+ binding by a series of metal chelators indicated that the affinities of the oncomodulin and 30 residue fusions for Tb3+ were approximately 10(11) M-1 and 10(7) M-1, respectively. Time-resolved lanthanide luminescence photography of electrophoresis gels demonstrated that the helix-loop helix Ca(2+)-binding could be used to specifically visualize the scFv fragment. PMID- 9373343 TI - Internal image rabbit anti-idiotypic antibody detects sheep antibodies to the bluetongue virus core protein VP7. AB - BACKGROUND: Rabbit polyclonal anti-idiotypic antibodies (anti-Id) were generated against three murine monoclonal antibodies (MAbs) specific for the group-specific antigen VP7 of bluetongue virus (BTV) by the sequential immunization method. It was demonstrated by serological tests that part of the anti-Id possesses the characteristics of internal image anti-Id. By affinity purification against the individual MAbs, the internal image anti-Id, designated RAb2-A, was isolated and identified as specific for the MAb, M1875. OBJECTIVES: To examine the ability of RAb2-A to detect sheep anti-VP7 antibodies by recognition of the common idiotype (Idx). STUDY DESIGN: Affinity-purified RAb2-A IgG, along with VP7, was applied on the solid-phase of ELISA plate and the membrane for Western blot analysis to detect anti-VP7 antibodies from sheep that were immunized with VP7 or were experimentally infected with BTV. An inhibition ELISA was employed to determine whether sheep anti-VP7 and M1875 recognize the same or similar epitope(s). RESULTS: RAb2-A recognised the Idx on anti-VP7 antibodies from sheep that were either immunized with VP7 or experimentally infected with BTV. Specificity of the reaction was confirmed by the observation that RAb2-A did not react with normal sheep serum or sheep antibodies against epizootic haemorrhagic disease of deer virus, a bluetongue-related disease virus in the Orbivirus genus. CONCLUSION: The ability of RAb2-A to detect anti-VP7 antibodies through recognition of the Idx suggests that RAb2-A can be used as a probe to detect anti-BTV antibodies. PMID- 9373345 TI - Immunotechnological products in adverse global environments. PMID- 9373346 TI - Synthetic peptide mimotope of the CAMPATH-1 (CD52) antigen, a small glycosylphosphatidylinositol-anchored glycoprotein. AB - BACKGROUND: CAMPATH-1 (CD52) antibodies are among the most powerful and specific lympholytic agents in humans and have numerous potential applications for human therapy. The CD52 antigen is a GPI-anchored glycoprotein with an exceptionally short peptide sequence of only 12 amino acids and a single, complex, N-linked oligosaccharide. Antibodies bind to the deglycosylated antigen and to a proteolytic fragment, but not to the synthetic peptide alone. OBJECTIVES: To characterise the antigenic epitope more precisely and to construct a synthetic analogue. Such an analogue would be useful for assay and purification of the therapeutic CAMPATH-1 antibodies as well as for studies of the antibody-antigen binding site. STUDY DESIGN: Collections of synthetic peptides based on the natural sequence were screened with a panel of CD52 antibodies. RESULTS AND CONCLUSION: A synthetic peptide composed of the natural C-terminal amino acids plus two additional residues was found to mimic the antigen with sufficient affinity to be useful for a variety of assays and for construction of an affinity matrix for antibody purification. Systematic mutation of this peptide enabled the definition of the critical residues for antibody binding, which will be of great help in building a model of the antibody-antigen interaction. Peptide mimotopes synthesised using a natural sequence as a starting point, rather than a completely random library, may be useful in many other similar circumstances. PMID- 9373347 TI - Design of cassette baculovirus vectors for the production of therapeutic antibodies in insect cells. AB - BACKGROUND: Various systems have been described for the expression of recombinant monoclonal antibodies for therapeutical applications. Insect cells offer great advantages with respect to post-translational modifications, stability, yields and applications. OBJECTIVES: To construct plasmid cassette transfer vectors in order to express chimeric, humanized or human antibodies in insect cells using baculovirus expression system. STUDY DESIGN: Two transfer vectors, pBHuC kappa and pBHuC gamma 1, were designed. They contain a viral promoter (polyhedrin or p10 promoters, respectively), a signal peptide sequence and a human immunoglobulin light chain C kappa gene or heavy chain C gamma 1 sequence, respectively. Restriction sites have been introduced to allow insertion of rearranged variable genes, after amplification by polymerase chain reaction. RESULTS: Recombinant baculoviruses expressing complete immunoglobulins have been generated by a double-recombination event between baculovirus DNA and the loaded cassette transfer vectors. CONCLUSION: Our genetic cassette approach makes this system a very flexible and convenient one for the rapid production of therapeutic monoclonal antibodies with heavy and light chains of any human isotype. Specific variable regions selected by the antibody phage display technology can be easily transferred in these vectors to obtain a complete antibody. PMID- 9373348 TI - Escherichia coli expression of a bifunctional Fab-peptide epitope reagent for the rapid diagnosis of HIV-1 and HIV-2. AB - BACKGROUND: The current format of a rapid whole-blood agglutination assay for HIV relies on a bifunctional molecule which comprises a 1C3 Fab fragment, with specificity for the human red blood cell surface marker (glycophorin A), chemically conjugated to a synthetic peptide that corresponds to a single immunodominant region of HIV envelope glycoprotein. In this assay erythrocyte agglutination occurs if the blood sample contains anti-HIV antibodies. OBJECTIVES: To establish whether a bacterially synthesised Fab fragment encoding several C-terminal immunodominant peptide tails can be produced in sufficient purity and yield to function in whole-blood agglutination assays. STUDY DESIGN: An E. coli dicistronic Fab expression cassette was constructed comprising of light and heavy chain gene fragments derived from a glycophorin specific monoclonal antibody (1C3), genetically linked with C-terminal immunoreactive peptide epitopes. Expression and purification procedures were established to enable the rapid production of 1C3 Fab-peptide epitope conjugates. RESULTS: A recombinant 1C3 Fab fragment was expressed with two different immunological epitope markers, Glu-Glu-Phe (EEF) and FLAG, at the C-terminus of the Fd heavy and kappa light chain, respectively. This model Fab-EEF/FLAG conjugate was detected in culture supernatant by SDS-PAGE gels and Western blots, and could be successfully used in erythrocyte agglutination assays. Furthermore, an HIV specific 1C3 Fab reagent, containing immunoreactive peptide epitopes from the surface glycoproteins of HIV-1 and HIV-2, was also expressed but at lower levels and with increased sensitivity to proteolytic degradation. Nevertheless, this recombinant Fab reagent with dual diagnostic specificity performed very effectively in whole-blood diagnosis of patients infected with either HIV-1 or HIV-2. CONCLUSION: A recombinant 1C3 Fab fragment terminated by immunoreactive peptide epitopes can be expressed in E. coli in a soluble, antigen-binding form, and it can successfully mimic the commercial Fab-HIV reagents in whole-blood agglutination assays. PMID- 9373350 TI - Identification of an antigenic peptide specific for bluetongue virus using phage display expression of NS1 sequences. AB - BACKGROUND: NS1 is a non-structural protein associated with the replication of bluetongue virus (BTV), an orbivirus (Reoviridae) that infects sheep and cattle. NS1 is potentially useful as a diagnostic antigen since the presence of specific antibodies is an indication that the virus has replicated in the host. It is, however, not antigenically unique and cross-reacts serologically with the analogous protein of the related epizootic haemorrhagic disease virus (EHDV). OBJECTIVES: To investigate phage display of peptides derived from the gene encoding NS1 as a way of identifying unique antigenic regions that can be mimicked by synthetic peptides. STUDY DESIGN: A cDNA clone of a large portion of the gene encoding NS1 of bluetongue virus was fragmented by partial DNase digestion. The fragments were ligated into the filamentous phage display vector, fUSE 2. Peptides expressed on the surface of the phages as part of the gene III proteins were selected from the library using antibodies affinity-purified from an antiserum to NS1. The peptides were identified by sequencing the phage DNA and alignment with the sequence of the target gene. RESULTS: Two antigenic regions were identified, one of which could be effectively mimicked by a 28 residue synthetic peptide. This peptide did not cross-react with an antiserum directed against NS1 of EHDV. CONCLUSION: The strategy of screening gene-derived phage display libraries with antibodies from an immune serum is expected to be useful in the development of highly specific peptide-based diagnostic assays. PMID- 9373349 TI - Induction of mucosal anti-HIV antibodies by facilitated transfection of airway epithelium with lipospermine/DNA complexes. AB - BACKGROUND: Expression of microbial protein sequences in eukaryotic cells transfected by transcriptional/translational permissive cDNA constructs can induce systemic humoral and cellular responses in vivo. Two methods of in vivo transfection have been described to date. One method uses large quantities of naked DNA injected into skeletal muscle. The second method uses relatively small quantities of DNA complexed to gold particles for bollistic penetration of the plasma membrane of keratinocytes. The major disadvantage of the bolistic method is that instrumentation is required which is not generally available. OBJECTIVES: The objectives of this study were to determine whether the use of DNA complexed with a cationic lipopolyamine could reduce the quantity of DNA required to induce systemic humoral responses following muscle transfection and whether similar DNA/lipopolyamine complexes could induce mucosal humoral responses following airway exposure. STUDY DESIGN: Balb/c mice were exposed by nasal aerosol or intramuscular inoculation to a mammalian transcriptional/translational permissive DNA construct containing the entire sequence for the HIV-1 envelope polyprotein. Experimental animals were further segregated by the number of exposures at 3-week intervals and whether the DNA was complexed to dioctadecylamidoglycylspermine (DOGS) at a 5:1 molar charge ratio of DOGS/DNA. RESULTS: DOGS facilitated in vivo transfection of mouse muscle reduced the quantity of DNA required for a systemic humoral response to surface expressed HIV-envelope proteins by one order of magnitude. Exposure of airway mucosa to both 10 micrograms and 1 microgram quantities of DNA complexed to DOGS produced systemic humoral responses to HIV envelope as well as mucosal antibodies in pulmonary and colonic epithelia. Molecular modeling of DOGS/DNA complexes at the 5:1 charge ratio used in this study indicates that the DNA component is not exposed to aqueous solvents and may be relatively resistant to degradation under common biological environments. CONCLUSION: Facilitated transfer of DNA by DOGS to transcriptional/translational competent cells offers several distinct advantages to the use of DNA alone. Since significantly smaller amounts of DNA are required, the potential for the induction of antibodies against DNA itself lessens the likelihood for the development of a lupus-like syndrome. More importantly, however, is the apparent ability to transfect mucosal cells which results in the development of specific mucosal immune responses. This procedure may allow the development of general methods for the induction of mucosal immunity at the level of entry for mucosal pathogens without the disadvantages inherent in live attenuated vectors. PMID- 9373352 TI - Some thoughts on quarantine changes in Hawaii. PMID- 9373351 TI - Generation and characterization of a single-gene encoded single-chain immunoglobulin-interleukin-2 fusion protein. AB - BACKGROUND: Interleukin-2 (IL-2), a potent inducer of cellular immune responses, has been used for biological therapy of human cancer; however, the high doses of IL-2 required to mediate patients' immune responses can cause considerable systemic toxicity. The murine monoclonal antibody (MAb) CC49, which reacts with tumor-associated glycoprotein (TAG)-72, expressed on a variety of human carcinomas, has shown excellent tumor localization in recent clinical trials. OBJECTIVES: Development and characterization of a single-chain immunoglobulin-IL 2 (SCIg-IL-2) fusion protein which, by delivering IL-2 selectively to the tumor site, can serve as an effective reagent for CC49/IL-2 combination therapy. STUDY DESIGN: A single-gene encoding the SCIg-IL-2 fusion protein derived from the chimeric (c) CC49 was designed, generated and inserted in an expression vector. The monomeric single-chain protein consisted of the CC49 heavy and light chain variable domains covalently jointed through a (GGGGS)3 linker peptide. The carboxyl end of the variable domain of the light chain was linked to the amino terminus of the human gamma 1 Fc through the hinge region, and the carboxyl end of the CH3 domain was linked to the amino terminus of the human IL-2 through a GGGSGGG linker peptide. The SCIg-IL-2, expressed from the murine myeloma cells transfected with the expression construct, was characterized for its antigen binding specificity, antibody effector functions and IL-2 biological activity. RESULTS AND CONCLUSION: Transfection of murine myeloma cells with the single-gene expression construct SCIg-IL-2 expressed a single-chain protein of approximately 70 kD, which was secreted into tissue culture fluid as a homodimer of approximately 140 kD. SCIg-IL-2 competed completely with cCC49 for binding to the TAG-72 antigen, but approximately three- to four-fold more of the SCIg-IL-2 was required to achieve levels of competition similar to those observed with the murine or chimeric CC49. With human effector cells, the fusion protein mediated lysis of TAG-72-positive human carcinoma cells. Prior treatment of human effector cells with 100 U/ml of human IL-2 enhanced the fusion protein-mediated cytolysis from 32 to 65%. At doses of > or = 1 ng/ml, the stimulatory effect of SCIg-IL-2 on IL-2 dependent murine HT-2 cell proliferation was comparable to that of the recombinant human IL-2. The single-gene construct may also facilitate inoculation of the gene in animal tissue for in vivo expression of the fusion protein. PMID- 9373353 TI - Chronic environmental cadmium toxicosis in horses and cattle. PMID- 9373354 TI - Could it happen here? PMID- 9373355 TI - What is your diagnosis? Bilateral perineal hernias. PMID- 9373356 TI - Theriogenology question of the month. Rupture of the prepubic tendon with additional tearing of the abdominal tunic. PMID- 9373357 TI - Enrollment in veterinary medical colleges, 1995-1996 and 1996-1997. PMID- 9373359 TI - Randomized controlled trial of cyclosporine for treatment of perianal fistulas in dogs. AB - OBJECTIVE: To evaluate efficacy of cyclosporine for treatment of perianal fistulas in dogs. DESIGN: Randomized, controlled trial. ANIMALS: 20 German Shepherd Dogs with naturally developing perianal fistulas. PROCEDURE: 10 dogs were treated with cyclosporine; the other 10 dogs were given a placebo. Overall improvement and change in total surface area of involvement and depth of the deepest fistula were determined after 4 weeks. Thereafter, cyclosporine-group dogs were treated for an additional 12 weeks and control-group dogs were treated with cyclosporine for 16 weeks. RESULTS: All cyclosporine-group dogs, but none of the control-group dogs, were subjectively improved after 4 weeks. Mean total surface area and mean fistula depth decreased 78 and 62%, respectively, in the cyclosporine-group dogs but increased 29 and 11%, respectively, in the control group dogs. After 16 weeks of cyclosporine treatment, fistulas had healed in 17 (85%) dogs. However, fistulas recurred in 7 of 17 dogs, and additional cyclosporine treatment or anal sacculectomy and surgical excision of fistulas was necessary. CLINICAL IMPLICATIONS: Cyclosporine appeared to be effective in dogs with perianal fistulas. Even in dogs in which fistulas were not completely healed, cyclosporine administration appeared to be beneficial, because the surgical procedures that were required were less extensive than those that would have been necessary if cyclosporine had not been given. PMID- 9373358 TI - Comparison of thoracic radiographs with images transmitted via advanced telecommunications equipment. AB - OBJECTIVE: To compare thoracic radiographs of clinically normal dogs and dogs with mild clinical heartworm disease with images transmitted by a desk-top, two way audiovisual teleconferencing system. DESIGN: Prospective, matched-set study. STUDY POPULATION: 50 thoracic radiographs from clinically normal and heartworm infected dogs and the digitally transmitted images of those radiographs. PROCEDURE: Thoracic radiographs from 25 clinically normal dogs and 25 dogs infected with 1 to 24 heartworms were evaluated by 3 clinicians. Using classic criteria for heartworm disease, evaluations of radiographs and images transmitted digitally over 2 high-speed data-transfer telephone lines (56 kilobits/s/line) were performed. Clinicians were asked to determine whether dogs had radiographic signs of heartworm disease. RESULTS: Clinicians' ability to detect heartworm disease did not differ between interpretations of radiographs and those of transmitted images. CLINICAL IMPLICATIONS: Radiographic images transmitted via a teleconference system can be used to provide reliable diagnostic information. Thoracic radiographs can be interpreted at a remote site permitting rapid consultation and immediate advice on clinical management. PMID- 9373360 TI - Photoreceptor outer segments in aqueous humor from dogs with rhegmatogenous retinal detachments. AB - OBJECTIVE: To determine whether photoreceptor outer segments can be found in aqueous humor from dogs with rhegmatogenous retinal detachment (RRD). DESIGN: Case series. ANIMALS: 4 dogs with unilateral RRD, 2 dogs with bilateral RRD, 1 dog with unilateral non-RRD, and 1 dog with glaucoma without retinal detachment. PROCEDURE: Aqueous humor samples were fixed in 2% glutaraldehyde and examined by means of transmission electron microscopy. RESULTS: Outer segments were found in aqueous humor from 7 of 8 eyes with RRD but were not found in aqueous humor from dogs with non-RRD or glaucoma. CLINICAL IMPLICATIONS: Photoreceptor outer segments may move into the anterior chamber of eyes with RRD. PMID- 9373361 TI - Primary lung tumors in cats: 86 cases (1979-1994). AB - OBJECTIVE: To classify histologic type and morphology of primary lung tumors in cats, to describe clinical findings in these cats, and to determine whether clinical findings were associated with histologic type or morphology. DESIGN: Retrospective study. ANIMALS: 86 cats with histologically confirmed primary lung tumors. PROCEDURE: Medical records for cats treated between 1979 and 1994 at any of 14 participating veterinary referral hospitals were reviewed. RESULTS: Weight loss, lethargy, and dyspnea were the most common clinical signs. Solitary or multiple pulmonary masses were seen on radiographs from 53 of 79 cats; effusion was seen on radiographs from the other 26. In 45 cats, tumors involved a single lung lobe. Caudal lung lobes were more commonly affected than were cranial lung lobes. Sixty-five cats had metastases. Tumors were classified as bronchial (n = 65), bronchiolar-alveolar (9), or other (12) and as poorly differentiated (59), moderately differentiated (20), or well differentiated (7). Breed, age, sex, weight, clinical signs, duration of clinical signs, and radiographic findings were not associated with histologic type or morphology. CLINICAL IMPLICATIONS: To identify possible occult primary lung tumors, thoracic radiography should be performed on cats with clinical signs of long duration, including weight loss, lethargy, and dyspnea. PMID- 9373362 TI - Intrinsic, management, and nutritional factors associated with equine motor neuron disease. AB - OBJECTIVE: To identify intrinsic, management, nutritional, and environmental risk factors associated with equine motor neuron disease (EMND) and to determine whether epidemiologic evidence supports oxidative stress as a risk factor for developing EMND. DESIGN: Case-control study. ANIMALS: 87 horses with EMND and 259 control horses. PROCEDURE: Information concerning each horse's history of exposure to multiple environmental factors prior to developing EMND was obtained by means of a questionnaire or personal interview. Exposure histories of horses with EMND and control horses were compared, and the association of each risk factor with EMND was evaluated, using logistic regression analysis. RESULTS: Factors significantly associated with risk of developing EMND included age, breed of horse, duration of residence at the farm, not vaccinating against rabies, and certain feeding practices. Horses that were exercised on green pasture or in grass paddocks were less likely to develop EMND, compared with horses that were exercised in dirt pad-docks. Feeding complete pelleted feed as the only source of concentrate or combined with sweet feed was associated with a significant increase in the risk of EMND. Supplementary feeding of vitamin and mineral mixtures not formulated to provide vitamin E or selenium was associated with increased risk of EMND. Horses with a history of cribbing or coprophagia were also at higher risk of developing EMND. CLINICAL IMPLICATIONS: Several husbandry practices and intrinsic characteristics of horses appear to modify the risk of EMND. The relationship of specific nutritional factors to EMND supports the hypothesis that a deficiency of vitamin E contributes to the disease. PMID- 9373363 TI - Evaluation of a test for identification of Arabian horses heterozygous for the severe combined immunodeficiency trait. AB - OBJECTIVE: To determine whether a recently developed test would correctly identify horses heterozygous for the severe combined immunodeficiency (SCID) trait. DESIGN: Case series. ANIMALS: 17 healthy Arabian horses that had previously produced foals with SCID, 1 healthy Arabian foal whose dam and sire had produced foals with SCID, 4 foals with SCID, and 1 healthy non-Arabian foal. PROCEDURE: DNA was extracted from leukocytes or fibroblasts, amplified by means of polymerase chain reaction, and hybridized with probes specific for the normal and mutant alleles of the catalytic subunit of DNA-dependent protein kinase, the factor whose absence is responsible for SCID in Arabian foals. RESULTS: Amplified DNA from the healthy non-Arabian foal hybridized only to the probe specific for the normal allele, whereas amplified DNA from the 4 foals with SCID hybridized only to the probe specific for the mutant allele. Amplified DNA from the 2 stallions and 15 mares hybridized with both probes, as did amplified DNA from the healthy foal whose dam and sire had previously produced foals with SCID, indicating that these horses were all heterozygous for the SCID trait. CLINICAL IMPLICATIONS: Results suggest that the genetic test will be useful in identifying Arabian horses heterozygous for the SCID trait and foals with SCID, provided that all Arabian horses with SCID have the same genetic mutation. PMID- 9373364 TI - Complications associated with use of a one-hole subpalpebral lavage system in horses: 150 cases (1977-1996). AB - OBJECTIVE: To determine type and frequency of complications associated with use of a one-hole subpalpebral lavage (SPL) system in horses. DESIGN: Retrospective study. ANIMALS: 150 horses with 156 SPL systems. PROCEDURE: Signalment, primary complaint, method used for placement, time SPL system was in place, and complications were retrieved from medical records. RESULTS: Complications were not associated with placement, maintenance, or removal of 66 of 156 (42%) SPL systems. A minor complication was reported in association with 53 (34%) SPL systems, and a serious complication was reported in association with 37 (24%). The 3 most common minor complications were mild swelling of the eyelid (31 horses), tearing of SPL system tubing (20), and loss of the injection cap (30). Serious complications included problems with the SPL system requiring its premature removal and possible replacement (26 horses), removal of the SPL system by the horse (6), infection of the eyelid (4), loss of the footplate in the eyelid (5), and cornea ulceration (1). CLINICAL IMPLICATIONS: Proper attention to the size of the footplate and placement of the SPL system in the eyelid should decrease the risk of serious complications. Minor eyelid swelling should be expected in the first 48 hours after SPL system placement. PMID- 9373365 TI - Evaluation of ruminal sulfide concentrations and seasonal outbreaks of polioencephalomalacia in beef cattle in a feedlot. AB - OBJECTIVES: To measure concentrations of thiamine in blood and sulfide in ruminal fluid in cattle with polioencephalomalacia (PEM) and to evaluate temporal associations between PEM and risk factors. DESIGN: Epidemiologic analysis. SAMPLE POPULATION: 14 steers with acute signs of PEM, 26 clinically normal steers and records of all cattle in a feedlot for the past 6 years. PROCEDURES: Concentrations of thiamine in blood and sulfide in ruminal fluid were measured. Values were compared between healthy steers that had been in the feedlot for 3 weeks or 2 months. Records were used to estimate the incidence of PEM and the time when cattle were at greatest risk of developing PEM. RESULTS: Thiamine concentrations in steers with PEM were within reference ranges. Healthy steers had significantly greater sulfide concentrations 3 weeks after entering the feedlot, when the incidence of PEM was greatest, than 2 months after entering the feedlot, when risk of developing PEM was low. Thiamine concentrations were within reference ranges at these times. Annually recurrent outbreaks of PEM during the summer began after initiating use of a water well containing a high content of sulfate. CLINICAL IMPLICATIONS: Excessive ruminal sulfide production is an important factor in the pathogenesis of PEM, without concurrent thiamine deficiency. Most cases of PEM developed between 15 and 30 days after introduction to a high-sulfur diet. When water is an important source of dietary sulfur, risk of PEM may increase during hot weather. PMID- 9373367 TI - Mortality trends for Alzheimer's disease, 1979-91. PMID- 9373366 TI - Treatment of dairy cows at parturition with prostaglandin F2 alpha or oxytocin for prevention of retained fetal membranes. AB - OBJECTIVE: To evaluate the effects of treatment at parturition with dinoprost tromethamine, fenprostalene, or oxytocin on postpartum disease and reproductive performance during the subsequent breeding season in dairy cows. DESIGN: Prospective study. ANIMALS: 1,400 Holstein cows from 5 commercial dairies. PROCEDURE: Cows were assigned within 2 hours after calving to serve as untreated control cows or to be treated with 1 mg of fenprostalene, SC; 25 mg of dinoprost tromethamine, IM; or 20 IU of oxytocin, IM. Cows were confined to treatment pens and monitored daily until fetal membranes were expelled. Cows with retained fetal membranes (RFM) were treated according to existing treatment protocols for the dairy, with the provision that intrauterine infusions were not allowed. All other disease conditions were recorded, and appropriate treatment was administered. Postpartum reproductive examinations were performed 28 to 56 days after parturition Breeding records were maintained for all cows until pregnancy was confirmed or the cow was removed from the herd. RESULTS: Fetal membranes were retained in 12.1% of all cows, and this outcome was unaffected by treatment. Compared with cows without RFM, cows with RFM had longer intervals to first insemination (76.4 vs 82.0 days), reduced first insemination conception rates (46.8 vs 28.0%), and increased number of days not pregnant (103.2 vs 127.4 days). Farm, as a variable, significantly affected development of RFM and postpartum disease conditions as well as reproductive performance during the subsequent breeding season. Fetal membranes were retained in 12.4, 15.2, 8.7, 6.3, and 16.9% of cows on farms 1, 2, 3, 4, and 5, respectively. Mean days to first insemination varied from 64.5 days (farm 3) to 91.5 days (farm 1). Mean number of days not pregnant varied from 94.8 days (farm 3) to 15.9 days (farm 4). CLINICAL IMPLICATIONS: Administration of prostaglandins or oxytocin at the time of calving does not reduce the incidence of RFM or improve reproductive performance. Farm management practices have the greatest impact on dairy cow performance. PMID- 9373368 TI - Leading causes of death by age, sex, race, and Hispanic origin: United States, 1992. PMID- 9373369 TI - Fetal mortality by maternal education and prenatal care, 1990. PMID- 9373370 TI - Medical and life-style risk factors affecting fetal mortality, 1989-90. AB - OBJECTIVES: This report presents fetal mortality data by medical and life-style risk factors of the mother and the fetus. METHODS: Deaths and fetal mortality rates are presented in this descriptive report. Data sources used are vital statistics data for fetal deaths and live births. RESULTS: The data that became available with the revision of the U.S. Standard Report of Fetal Death in 1989 expanded the medical and health data available on mothers and fetuses. Reporting of medical conditions is probably incomplete for fetal deaths as well as for live births. Therefore, caution should be exercised in using this data. Reported occurrences of medical and life-style risk factors of mother and fetus for fetal deaths and live births and fetal mortality rates are presented. Maternal medical conditions most often associated with having a fetal death were problems with amniotic fluid levels and blood disorders. Fetal mortality was 35 percent greater when tobacco was used during pregnancy and 77 percent higher when alcohol was consumed during pregnancy. The complication of labor most often associated with fetal mortality was abruptio placenta. Although a very small proportion of all deliveries have specific congenital anomalies reported, fetal mortality was close to 50 percent for anencephalus, about 25 percent for renal agenesis, and slightly more than 20 percent for hydrocephalus. PMID- 9373372 TI - Perceived determinants of risk for breast cancer and the relations among objective risk, perceived risk, and screening behavior over time. AB - Interrelations among perceived risk for breast cancer, objective risk factors, and both breast self-examination (BSE) and mammography screening were examined across two waves of a longitudinal study of breast cancer screening. Participants were a community sample of 335 predominantly White middle-class women, aged 37 to 77, who had not had breast cancer. Factors believed by women to determine their self-rated risk level for breast cancer were investigated. Women held optimistic biases about their own breast cancer risk; they often erroneously attributed their relatively lower perceived risk to personal actions, including mammography screening. Compliance with mammography screening but not BSE recommendations increased over time. Perceived susceptibility to breast cancer was related to both family history and breast symptomatology; early mammography screening was positively related to perceived susceptibility later in time. PMID- 9373371 TI - Women and health: in search of a paradigm. AB - The growing interest in women and health is resulting in an expanding number of important issues and invested disciplines. In this article, we propose a framework to serve as a guide for organizing themes and integrating competing approaches to the field of women's health. Our framework is illustrated through a multilevel circular model that graphically represents the evolving nature of the field. We first describe key content areas in women's health, including topics that have traditionally been considered, as well as those that have only more recently received attention. We then discuss research processes and methods that are important in the field and call for the use of approaches often excluded from traditional scientific procedures. Finally, we address the conceptual models that various disciplines provide and the advantage of a multidisciplinary perspective to advancing the field of women's health. PMID- 9373373 TI - Psychosocial predictors of postpartum depressed mood in socioeconomically disadvantaged women. AB - The effects of stress, social support, and labor and delivery experiences on postpartum depressed mood were examined in an ethnically diverse sample of low income women (N = 108). Women were interviewed on multiple occasions throughout pregnancy and then once approximately 2 months postpartum. Information on labor and delivery outcomes was abstracted from medical charts. Results indicated that women who were more satisfied with the prenatal social support they received were less likely to experience postpartum depressed mood, after controlling for prenatal depressive symptomatology. In addition, women who experienced more distressing life events during pregnancy and who reported higher levels of prenatal anxiety were also more likely to feel depressed, after controlling for all other factors in the model. Finally, women who were more satisfied with their labor and delivery experience tended to be less depressed in the early months following childbirth. Together, these variables accounted for 45% of the variance in postpartum depressed mood. PMID- 9373374 TI - Patient gender and communication with physicians: results of a community-based study. AB - An observational study of 648 routine medical visits with 69 physicians examined patient gender in relation to patient and physician communication, patient preference for the physician's communication style, patient satisfaction, and the physician's awareness of the patient's satisfaction. Data consisted of audiotapes as well as patient and physician questionnaires. Women appeared to be more actively engaged in the talk of medical visits--they sent and received more emotionally charged talk and were judged by independent raters as more anxious and interested both globally and in terms of voice quality than men. Consistent with the more emotional talk, women reported preferring a more "feeling-oriented" physician than male patients did. Mean levels of satisfaction with communication did not differ by gender, and communication predictors of satisfaction were similar for male and female patients, although they were stronger for male patients. Physicians were significantly less aware of some aspects of female patients' satisfaction compared to male patients' satisfaction. In light of the weaker correlations between patients' communication and their satisfaction for women, we suggest that women provided fewer obvious cues to their satisfaction. Training in communication skills may increase open discussion about feelings and emotions and may also produce greater physician sensitivity to patients' satisfaction, particularly with female patients. PMID- 9373375 TI - Policy research: balancing rigor with relevance. AB - Behavioral and psychosocial research, biomedical research, and public health have evolved as separate cultures, with different languages, priorities, and goals. Yet all of these cultures are developing their own specialized perspectives on issues related to women's health, and the resulting fragmentation and competition for limited resources could complicate the development of comprehensive health policy in this area. The purpose of this article is to search for common ground among a broad range of clinical, research, and policy issues that are likely to affect the emerging field of women's health. In the article, I describe the policy process, with an emphasis on women's health agencies at the Federal level; discuss broad methodological and technical issues from the perspectives of researchers and policy makers; and describe some innovative national initiatives involving public-private partnerships among clinicians, researchers, and policy makers. The policy context may help researchers and clinicians to coordinate, reframe, and restructure their specialized agendas and to develop a more comprehensive and unified approach to women's health. PMID- 9373376 TI - Resilience and thriving in response to challenge: an opportunity for a paradigm shift in women's health. AB - The purpose of this article is to move beyond the vulnerability/deficit model of women and to focus on women's strengths and their ability to thrive in the face of adversity. Thriving is a dynamic process of adaptation, influenced by numerous individual and social factors; it emerges and changes over the life course and may be identified in behavioral, cognitive, or affective domains. The foundation of this concept comes from the literature on resilience, but it goes beyond the common view of resilience as homeostasis. It suggests, instead, a value-added construct whereby challenge provides an opportunity for change and growth. Understanding the concept and process of thriving can provide an important basis for theoretical development, empirical research, and clinical intervention. Thriving can provide a framework within which to examine the antecedents and consequences of differential reactions to health-related challenges. Knowledge of the factors that promote thriving can provide an important foundation for a paradigm shift away from a focus on illness and pathology toward one that understands, explains, and nurtures health. PMID- 9373377 TI - Reactions to impaired fertility: the vicissitudes of primary and secondary control appraisals. AB - Recent formulations about how perceived control influences adaptation to chronic medical conditions suggest that although a sense of personal (primary) control may decline over time, there are ample opportunities for individuals to make other adaptation-enhancing "secondary control" appraisals such as construing benefits or finding meaning in their threatening circumstance. We describe a longitudinal study of men and women with impaired fertility that evaluates a dynamic relation between primary and secondary control--one in which anticipated benefits increase over time as failed efforts to achieve a desired pregnancy lead to declines in primary control. Forty-six men and women with impaired fertility rated their sense of personal control over fertility outcomes, the extent to which they anticipated benefits in this situation and their outcome expectancy on two occasions separated by 14 months. As predicted, perceived control diminished over time. Changes in anticipated benefits were unrelated to changes in personal control. Anticipating benefits, however, was inversely related to changes in outcome expectancy, such that a more pessimistic expectancy over time was associated with an increase in anticipated benefits. This relation was independent of perceived control and was not mood dependent. We discuss these findings in terms of current theories of control, the need for further longitudinal investigations to evaluate the temporal relations between primary and secondary control appraisals, and implications for infertility research. PMID- 9373378 TI - Sources of social support as predictors of exercise adherence in women and men ages 50 to 65 years. AB - Examines types of social support that best predicts adherence at different time points during a 1-year endurance exercise program in 269 women and men ages 50 to 65 years. Results indicate that social support had similar effects on exercise participation for women and men, and support specific to exercise was a better predictor of exercise adherence than general social support. A preference for receiving a lesser amount of initial support from exercise staff was the strongest social support-related predictor of exercise adherence during the initial 6 months of the program. Support currently received from family and friends and exercise staff at Month 6 was found to be the strongest predictor of adherence during Months 7 to 12. Format of exercise was also a strong predictor of exercise adherence with home-based programs related to greater adherence. Additionally, divorced nonsmokers appear to be at increased risk for poor early exercise adherence and should be targeted in interventions to promote exercise participation. PMID- 9373379 TI - Women and the 1993-1994 health reform debate: issues and questions. AB - Provides a review of the major issues raised during the 1993-1994 national health reform debate, with emphasis on the implications of these issues for women's health. I begin with an overview of the current health care system and the access to care by women in it, based in part on their health characteristics. The need to reform the current system is noted, along with a discussion of the major issues and proposals debated during 1993-1994, the years of the 103d US Congress. Questions are raised that could enable women's health advocates and activist women health care consumers to assess the implications for women of various future health reform proposals. PMID- 9373380 TI - The social construction of breast loss and reconstruction. AB - Reconstructing the breasts of women with breast cancer is standard medical care. An exploratory, qualitative study of women with breast cancer demonstrates that breast reconstruction is not essential to the resolution of a breast cancer crisis. This article reveals that today's culture creates a social context in which breast loss appears to have dire consequences for women and then provides the medical care to redress the loss it has helped create. Interviews were held with 29 women to explore the psychosocial consequences of breast cancer on their health and lives. This study demonstrates that breast reconstruction fails to meet the expectations of these women with breast cancer because the women identify disjunctures between social expectation and their own interests in health and well-being. PMID- 9373381 TI - Screening mammography: factors associated with adherence to recommended age/frequency guidelines. AB - Examines associations of selected demographic, insurance, health care, health history, and health practice variables with frequency of screening mammograms received during the past 5 years. Telephone interviews were conducted with 350 women aged 40 through 69, never diagnosed with breast cancer, and identified through random digit dialing in Connecticut. Of 10 variables showing bivariate associations with receiving mammograms as frequently as recommended by National Cancer Institute guidelines, younger age, having a first-degree relative with breast cancer, and having annual clinical breast examinations were statistically significant independent predictors in logistic regression analyses of regular utilization of mammography during the past 5 years. In additional logistic analyses, having regular clinical breast exams maintained a strong effect on the odds both of having any mammograms and, among respondents reporting any mammograms, of having the recommended number during the past 5 years. Frequency of breast self-examination was unrelated to frequency of mammograms. PMID- 9373382 TI - Couples and chronic obstructive airway diseases: the role of gender in coping and depression. AB - Social support, stress, health locus of control, active and avoidance coping, and depression were studied with 107 married couples in which one partner had a chronic obstructive airway disease (mean age = 62 years old). Differences between couples were evident when gender of the patient was assessed. Female patient couples that were older appeared more at risk than male patient couples for distress. In the analyses of spouse depression, gender moderated the relation of coping, social support, and health locus of control with depression. For patients, coping and social support were directly related to depression rather than moderated by gender. Implications for prevention and future research are discussed. PMID- 9373383 TI - Conception, commitment, and health behavior practices in medically high-risk pregnant women. AB - Based on cognitive dissonance and related theories of commitment, this study tested hypotheses that planning pregnancy and number of months spent trying to conceive would be associated with better prenatal health behaviors and that commitment to pregnancy and motherhood would mediate these associations. Participants (N = 96) were pregnant women at high medical risk for an adverse birth outcome. As predicted, planning pregnancy predicted better prenatal health care practices, and this effect was mediated by commitment level. Among women who planned their pregnancy, longer time to conceive predicted higher commitment but did not influence prenatal health behaviors directly. Women who had given birth previously practiced fewer prenatal health behaviors. Commitment, however, remained the strongest predictor of prenatal health care practices. Results are consistent with theories of commitment and with prominent approaches to the study of health behavior. PMID- 9373384 TI - Measuring battering: development of the Women's Experience with Battering (WEB) Scale. AB - Measuring only the physical markers of violence (e.g., slapping, beating) fails to capture the chronic vulnerability and gendered nature of battered women's experiences. Instruments that measure only observable discrete events may mask the continuous nature of battering and the relation between events and experience. Our approach to measuring battering operationalizes the experiences of battered women rather than the abusive behaviors they encounter. This alternative approach emphasizes the meanings battered women attach to the violence and to battering as an enduring presence in their lives. Focus groups with 22 battered women generated qualitative data for developing scale items (Smith, Tessaro, & Earp, 1995) and a known-groups survey with 185 battered and 204 nonbattered women determined the final scale items. Factor analysis of 40 initial items revealed a strong single-factor solution. The resulting 10-item Women's Experiences with Battering (WEB) Scale demonstrated high internal consistency reliability, was significantly correlated with known-group status, exhibited good construct validity, and was not significantly correlated with a measure of social desirability. The WEB Scale provides researchers with a valid and concise measure for studying relations between battering and health or health behavior, as well as evaluating the impact of interventions on battered women or prevalence. PMID- 9373385 TI - Sexual assault, social reactions, and physical health. AB - This study examined the role of postassault social reactions in the association between sexual assault and physical health in a convenience sample of 155 women completing a mail survey. Regression analysis showed that tangible aid/information support and depressive symptoms were each related to poorer perceived health, whereas other positive social reactions (e.g., emotional support/validation) were related to better health perceptions. More severe (e.g., physically violent) assaults were associated with poorer current perceptions of one's physical health. Negative social reactions (e.g., distraction/discourage talking) mediated this association, suggesting that the link between assault severity and poorer health may be due to increased negative social reactions to victims of these assaults. Implications for studying the role of social reactions in relation to health consequences of sexual assault are discussed. PMID- 9373386 TI - Female circumcision among Egyptian women. AB - Although a remarkable degree of consensus has been reached among international agencies, policymakers, and women's health advocates that the practice of female circumcision should be eliminated, such consensus is not necessarily shared by those who perform the operation or the families responsible for having girls excised. The surgical procedure is nested in a complex set of beliefs about identity, moral behavior, and the working of the female body. This article describes the dominant themes produced in 85 extensive interviews with mother and operators representing the broad spectrum of Egyptian society. The interviews detailed the operation itself, women's emotional response to the operation, and the rationales put forth in support of the practice. Although institutional efforts to eliminate the practice will meet with resistance, significant demographic shifts already taking place are producing changes in family systems and the opportunity structure that coincide with the abandonment of excision in key sectors of the urban population. PMID- 9373387 TI - Need for certainty and interest in genetic testing. AB - The relation among need for certainty, type of information presented about a genetic test, and level of interest in predictive genetic testing was examined. Participants were randomly assigned to receive 1 of 2 descriptions of the test. The only difference between the descriptions was that one included a paragraph that emphasized the cancer risk remaining for those who test negative for gene mutations. As predicted, a significant interaction between need for certainty and type of information presented was observed. Whereas women high in need for certainty were more interested in genetic testing when provided with the standard description and less interested when provided with the more complete one, women low in need for certainty showed the opposite pattern. The results suggest that interest in genetic testing is determined by the correspondence between an individual's personal goals and her perception of the kind of information provided by the test. PMID- 9373389 TI - [Options in the therapy of bronchial carcinoma: new perspectives through multimodal concepts with Paclitaxel]. PMID- 9373388 TI - [Sex hormone steroids and the cardiovascular system]. PMID- 9373390 TI - [Comorbidity in cardiac insufficiency]. PMID- 9373392 TI - Effect of selective alteration of membranous or cytoplasmic properties on erythrocyte elongation in shear flow. AB - This study examines the relative contributions of the cytoplasmic and membranous compartments to the shear-induced elongation of single red blood cells (RBC). The mechanical properties of the cell membrane of normal human RBC were altered by controlled heat treatment (HT) (48 degrees C for 1, 5 and 9 min). Using RBC transformed by conversion of intracellular hemoglobin to methemoglobin with nitrite as the oxidizing agent, a concomitant modification of cytosolic rheological properties was achieved by the same HT procedure. On exposure to heat, the viscosity of the methemoglobin solutions increased considerably. Cell elongation was measured in Dextran 60 suspensions sheared in a cone and plate rheoscope. Normal cells after 5 min of HT, and transformed cells after 1 min of HT yielded a two phase index of elongation curve which had a zero value within the lower shear rate range. Consequently, two indices of stiffening were introduced. One characterized the shear rate of transition from the zero value to the second inclined portion of the elongation curve. This index related to those cells that were oriented in the flow field but were not elongated. The other index characterized the maximum elongation at maximal shear rate in the rheoscope. In spite of the different kinematic states of cells described by the above two indices, identical rates of stiffening, as measured by the critical shear rate at which elongation sets in, or by the elongation parameter, with time of HT, were observed for normal and transformed cells. Further, transformed cells were stiffer than normal cells throughout the time of HT. These results may be explained by assuming that methemoglobin (MetHb) was bound to the endoface of the erythromembrane. The contribution of cytosolic dissipation of energy to cell elongation appears to be small. PMID- 9373393 TI - Deformation of erythrocytes under shear: a small-angle light scattering study. AB - In this study, sharp small-angle light scattering (SALS) images of erythrocytes under increasing shear stresses in a Couette flow were obtained, and accurate measurements of the angular positions of the two first minima and maxima have been carried out. The deformed cells were assumed to be three-axis ellipsoids of constant volume for all shear stresses. Application of the Physical Optics Approximation (POA) then permitted the determination of the cell dimensions as a function of the applied shear stress. Our results agree with determinations obtained by other methods. PMID- 9373391 TI - [Angiotensin-II-antagonism: new hope for the management of cardiac insufficiency]. PMID- 9373394 TI - Platelet adhesion onto the wall of a flow chamber with an obstacle. AB - In the present study, the data of the initial adhesion of platelets onto the wall of a flow chamber with an obstacle in steady human blood flows were obtained. The flowfields and the distribution of stress-related factors were simulated numerically by a finite volume method and the fluid dynamic effect on the platelet adhesion is discussed. In addition to the wall shear effect, the normal stress effect was also taken into account. A parameter Vn/[Vt] was devised to assess the combined effect of both shear and normal forces in platelet adhesion. It was found that the peak adhesion occurred next to, but not on, the impingement point on the obstacle where the value of Vn/[Vt] was negative. In these regions, direct impact played a major role in platelet adhesion. On the other hand, near the separation point before the obstacle where Vn/[Vt] was insignificant, the mechanism was believed to be different from that in the direct impact region. Denser adhesion there might be caused by the accumulation and frequent collision of particles due to flow retardation and/or detour of the flow path. Interestingly, relatively low adhesion was found inside the recirculation regions. These results show that the normal stress effect (impingement) should be considered in platelet adhesion in addition to the shear effect. PMID- 9373395 TI - The applicability of the time/temperature superposition principle to brain tissue. AB - This paper deals with the mechanical characterization of brain tissue which behaves as a viscoelastic material. We focus on the linear viscoelastic behavior, which should apply for small strains at any strain rate, and demonstrate the applicability of the time/temperature superposition principle. This principle allows the opportunity to extend the range of shear rates for which the material is characterized, and makes the results applicable to impact conditions. This characterization of the linear behavior forms the basis for a further nonlinear characterization of the tissue. PMID- 9373396 TI - Swelling of hydrocolloid dressings. AB - Wound healing is promoted by dressings that maintain a moist environment. Specifically, hydrocolloid dressings allow excess fluid to escape without permitting wound desiccation. However, the fluid handling capacity of hydrocolloid dressings depends on many factors such as the physicochemical properties of the gel formulation, and the design of the dressing. We measured the moisture uptake kinetics of different hydrocolloid dressings by placing the gel side of a sample in contact with water. The time evolution of the thickness was measured by means of a video camera linked to a computer. The theory of Tanaka and Fillmore (1979) was used to predict the kinetics of uniaxial swelling of a cylindrical gel sample. The model allows to associate to an experimental curve a total thickness increase hf-h0 (where hf and h0 are respectively the final and initial thickness) and a characteristic time tau. The model also relates hf-h0 and tau to the physiochemical composition of the dressing, and to the initial thickness h0. The influence of h0 is discussed by means of experiments performed on dressings with different initial thickness. PMID- 9373397 TI - Trauma centres in the UK. PMID- 9373398 TI - Necrotizing enterocolitis: pathogenesis and treatment. PMID- 9373399 TI - Posterior cruciate ligament injuries. AB - Until recently, the function of the posterior cruciate ligament has been poorly understood and the traditional wisdom is that injuries to this ligament do not result in any appreciable functional disability. There is increasing evidence, however, that the natural history may not be as benign as was originally assumed. This review seeks to analyse current knowledge concerning the function, diagnosis, natural history and treatment of this injury. PMID- 9373400 TI - Anterior cruciate ligament. AB - Anterior cruciate ligament surgery is currently widely practiced. Nevertheless it is a surgery which is performed electively, mostly in young healthy adults who chose to continue in their sporting endeavours. We present a short account of the various aspects of this surgery as well as our preferred technique and results. PMID- 9373401 TI - The management of acute traumatic haemarthrosis of the knee. AB - The knee is the largest synovial joint in the body, with a number of diverse soft tissue structures contributing to its stability. It is subject to enormous stresses and is the most commonly injured joint. These injuries usually occur in young, active patients. This article describes the approach to managing these important injuries. PMID- 9373403 TI - Somatization disorder. PMID- 9373402 TI - Fetal tachyarrhythmias. AB - Fetal tachyarrhythmias are uncommon but are associated with significant perinatal mortality and morbidity. Fetal echocardiography permits the accurate determination of the nature of the arrhythmia. Transplacental or direct fetal therapy with anti-arrhythmic drugs can successfully cardiovert the fetus in utero with a subsequent reduction in perinatal problems. The investigation and management of these unusual conditions is reviewed. PMID- 9373404 TI - Munchausen's syndrome: rule breakers and risk takers. PMID- 9373405 TI - Munchausen's syndrome coexisting with other disorders. PMID- 9373406 TI - Anaesthetic management of the severely injured patient: chest injury. AB - Life-threatening haemorrhage is common in major chest and abdominal trauma (Figure 1). Management consists of rapid fluid transfusion via large bore intravenous cannulae and early surgical intervention if indicated. Refractory hypoxaemia is frequently present in the chest injured patient (Figure 2). Pneumothorax and haemothorax must be carefully sought, and chest drains used in their management. Hypoxaemia secondary to simple chest injury should be managed with oxygen administration and the provision of analgesia initially. Resistant hypoxaemia may necessitate intubation and ventilation. PMID- 9373407 TI - Resuscitation III: advanced trauma life support. AB - Trauma is the leading cause of death in people less than 40 years old (Central Statistics Office, 1994). Patients who have sustained major trauma will often have multiple injuries. The key to treating these patients is an organized and systematic method of examination and treatment to ensure that injuries are not missed and left untreated. PMID- 9373408 TI - Patterns of viral hepatitis in Hong Kong. AB - Viral hepatitis is the most common form of acute or chronic hepatitis in Hong Kong. This article outlines current patterns of viral hepatitis in Hong Kong, and discusses the diagnosis, prevention and treatment of the different forms of the disease. PMID- 9373409 TI - Mycoplasma pneumoniae infection presenting as haemolytic anaemia. PMID- 9373410 TI - The role of the CCDC. PMID- 9373411 TI - The role of the CCDC. PMID- 9373412 TI - Emergency care outside hospital. PMID- 9373414 TI - Listening to patients. PMID- 9373413 TI - Medicine and the Internet. PMID- 9373415 TI - Suicide and substance misuse. PMID- 9373416 TI - Ethnicity in psychiatric epidemiology: need for precision. PMID- 9373417 TI - A very British kind of social psychiatry. PMID- 9373418 TI - The evolving face of psychiatric epidemiology. PMID- 9373420 TI - Controlled acute and follow-up trial of cognitive therapy and pharmacotherapy in out-patients with recurrent depression. AB - BACKGROUND: We report a randomised controlled trial, in both the acute and maintenance stage of treatment, in 75 out-patients with recurrent major depression. METHOD: Patients were allocated to three groups: 16 weeks of acute treatment and two years' maintenance treatment in the following way: antidepressants and maintenance antidepressants; cognitive therapy and maintenance cognitive therapy; antidepressants and maintenance cognitive therapy. Both completers' and end-point data were analysed. RESULTS: In the acute phase of treatment, all patients improved significantly and there was no significant difference among treatments, or in the pattern of improvement over time. In the maintenance stage of treatment, patients kept improving over time in all three groups and there was no significant difference among treatments. Cognitive therapy was consistently superior to medication. CONCLUSIONS: The results indicate that maintenance cognitive therapy has a similar prophylactic effect to maintenance medication and is a viable option for maintenance after acute treatment with medication in recurrent depression. PMID- 9373419 TI - London-East Anglia randomised controlled trial of cognitive-behavioural therapy for psychosis. I: effects of the treatment phase. AB - BACKGROUND: A series of small, mainly uncontrolled, studies have suggested that techniques adapted from cognitive-behavioural therapy (CBT) for depression can improve outcome in psychosis, but no large randomised controlled trial of intensive treatment for medication-resistant symptoms of psychosis has previously been published. METHOD: Sixty participants who each had at least one positive and distressing symptom of psychosis that was medication-resistant were randomly allocated between a CBT and standard care condition (n = 28) and a standard care only control condition (n = 32). Therapy was individualised, and lasted for nine months. Multiple assessments of outcome were used. RESULTS: Over nine months, improvement was significant only in the treatment group, who showed a 25% reduction on the BPRS. No other clinical, symptomatic or functioning measure changed significantly. Participants had a low drop-out rate from therapy (11%), and expressed high levels of satisfaction with treatment (80%). Fifty per cent of the CBT group were treatment responders (one person became worse), compared with 31% of the control group (three people became worse and another committed suicide). CONCLUSIONS: CBT for psychosis can improve overall symptomatology. The findings provide evidence that even a refractory group of clients with a long history of psychosis can engage in talking about psychotic symptoms and their meaning, and this can improve outcome. PMID- 9373421 TI - Type of hospital setting and treatment outcome with heroin addicts. Results from a randomised trial. AB - BACKGROUND: General psychiatrists have recently been encouraged to provide treatment to heroin addicts, including in-patient detoxification. No comparison has previously been made of specialist versus general psychiatric in-patient care. METHOD: During a randomised study of cue exposure, 186 opiate addicts were also randomised to either specialist in-patient (DDU; n = 115) or general psychiatric (GEN; n = 71) wards in the same hospital. RESULTS: From pre-treatment (post-randomisation) onwards, patient outcomes differed across the two in-patient settings. Of the original randomised sample, significantly more DDU than GEN subjects accepted their randomisation (100 v. 77%), were subsequently admitted (60 v. 42%), and completed in-patient detoxification (45 v. 18%). Of patients admitted, more DDU than GEN patients completed detoxification (75 v. 43%). During seven-month follow-up, of those 43 patients who reached the end of treatment, significantly more ex-DDU than ex-GEN subjects were opiate-free. CONCLUSIONS: From pre-treatment onwards, significant differences in process and outcome were found after allocation to treatment on either DDU or GEN. Further randomised studies are required to replicate and explain these findings. PMID- 9373422 TI - Efficacy and safety of two new methods of rapid intravenous detoxification in heroin addicts previously treated without success. AB - BACKGROUND: New methods of rapid opiate detoxification, under intravenous sedation, can detoxify heroin-addicted patients in 24 hours. Their clinical application has been limited by the lack of studies establishing both efficacy and safety. METHOD: In a randomised, controlled study, 300 treatment-refractory, heroin-addicted patients received rapid intravenous detoxification treatment (naloxone infusion, 0.06-0.08 mg/kg, then oral naltrexone 50 mg/day) under either monitored light intravenous sedation or unmonitored deep intravenous sedation. RESULTS: All patients were successfully detoxified and 93% remained abstinent one month later. Severity of withdrawal, according to the Wang Scale modified by Loimer, was 4.9 (s.d. 3.0) points in the light sedation group and 4.8 (s.d. 2.9) in the deep sedation group (P = 0.26). Two patients (1.3%) in the light sedation group and four (2.6%) in the deep sedation group required tracheal intubation (P = 0.31). There was only one severe complication, a case of nosocomial aspirative pneumonia which improved with antibiotic treatment. CONCLUSIONS: Successful rapid intravenous detoxification can be achieved using relatively light levels of sedation. PMID- 9373423 TI - Brain blood flow in anxiety disorders. OCD, panic disorder with agoraphobia, and post-traumatic stress disorder on 99mTcHMPAO single photon emission tomography (SPET). AB - BACKGROUND: We compared regional cerebral blood flow (rCBF) in three groups of patients with DSM-III-R anxiety disorders. METHOD: Fifteen patients with obsessive -compulsive disorder (OCD), 15 with panic disorder with agoraphobia (PA), and 16 with post-traumatic stress disorder (PTSD) and a similar group of healthy controls were assessed on brain-dedicated high-resolution SPET. RESULTS: MANOVA revealed significant rCBF differences between diagnostic groups (F = 4.4; d.f. = 3, 57; P = 0.007) and between cerebral regions (F = 6.4; d.f. = 1, 57; P = 0.01) in OCD and PTSD compared with PA and healthy controls, limited to bilateral superior frontal cortices and right caudate nuclei. Whole brain blood flow correlated positively with anxiety (r = 0.24, n = 46, P = 0.05). Beck depression scores correlated significantly negatively with left caudate rCBF (r = -0.24, n = 46, P = 0.05) and right caudate rCBF (r = -0.31, n = 46, P = 0.02). PTSD syndrome severity correlated significantly negatively with the left caudate (r = -0.49, n = 16, P = 0.03) and with right caudate rCBF (r = -0.7, n = 16, P = 0.001). CONCLUSIONS: Functional rCBF differences in anxiety disorders could relate to repetitive, intrusive, distressing mental activity, prominent in both OCD and PTSD. PMID- 9373424 TI - Strategies for preventing suicide. AB - BACKGROUND: The Health of the Nation includes a target for reducing population suicide rates. We have examined and quantified various high-risk and population based strategies for prevention based upon a number of stated assumptions and hypothetical interventions. METHOD: The published literature was used to estimate the population attributable fractions for both high-risk and population-based strategies. The number needed to treat for the high-risk strategies was calculated, assuming an intervention that reduced suicide rates by 25%. RESULTS: Interventions that would reduce rates of suicide by 25% would reduce population rates by about 2.6% for those recently discharged from hospital and by up to 5.8% for those presenting to general hospital with deliberate self-harm. The population attributable fraction for unemployment was 10.9%. CONCLUSIONS: High risk strategies will have only a modest effect on population suicide rates, even if effective interventions are developed. Evaluating interventions for deliberate self-harm patients seems worthwhile. The UK Government's target for suicide reduction is more likely to be achieved using population-based strategies. Reducing the availability of methods commonly used for committing suicide is the most practicable current policy, although more radical approaches, for example reducing unemployment, may also substantially reduce suicide rates. PMID- 9373425 TI - Risk factors for suicide in patients with schizophrenia: nested case-control study. AB - BACKGROUND: Of 9156 patients admitted to psychiatric hospitals in Denmark between 1970 and 1987 and diagnosed for the first time as having schizophrenia, 508 committed suicide. The purpose of the study was to identify risk factors for suicide among patients with schizophrenia, particularly factors relating to hospitalisation. METHOD: From the cohort of all 9156 patients, the 508 who had committed suicide were individually matched to 10 controls from the same cohort, and data were analysed using conditional logistic regression. RESULTS: Suicide risk was particularly high during the first 5 days after discharge, and increased risk was also associated with multiple admissions during the previous year, previous suicide attempts, previous diagnosis of depression, male gender, and previous admissions to general hospitals for physical disorders. After adjusting for these factors, no effect was found for age. There was some evidence of an excess of suicides during temporary leave from the psychiatric department. CONCLUSIONS: The findings suggest that preventive measures could be focused on the first period after discharge, when closer monitoring and better social support may be needed. This may also apply to patients on temporary leave during a period of admission. PMID- 9373426 TI - Poor memory, negative symptoms and abnormal movements in never-treated Indian patients with schizophrenia. AB - BACKGROUND: Cognitive impairment, frequently found in patients with schizophrenia, may be associated with negative symptoms and dyskinesia. However, antipsychotic medication may be a confounding variable. These putative associations may be clarified by examining never-treated patients. METHOD: Never treated elderly schizophrenic patients (n = 19) living in south-east India were compared with treated patients (n = 25) and normal subjects (n = 55). Memory was assessed by the Wechsler Memory Scale, negative symptoms by the Positive and Negative Syndrome Scale, and dyskinesia by the Abnormal Involuntary Movements Scale. RESULTS: Normal subjects had a higher mean memory quotient than patients. There were no significant differences between never-treated and treated patients. Negative symptoms were associated with a poorer memory in the never-treated group. There was no association between memory and dyskinesia. CONCLUSIONS: There is an association in never-treated patients between a poorer memory and negative symptoms, but not between a poorer memory and dyskinesia. PMID- 9373427 TI - Financial cost of treating out-patients with schizophrenia in Nigeria. AB - BACKGROUND: An assessment of the monetary costs of treating a group of Nigerian out-patients with schizophrenia, in comparison with insulin-dependent diabetics, was made. METHOD: Fifty out-patients with schizophrenia (mean age 42.9) and 40 with diabetes (mean age 41.9), attending government hospitals in Lagos, were assessed at six-monthly intervals, for direct and indirect costs (US$ = 82 naira; minimum monthly wage = 500 naira). RESULTS: Twenty (40%) of those with schizophrenia and eight (20%) of the diabetics had no income at all. The mean total cost of schizophrenia in six months (2941.4 naira) or US$ 35.9) was significantly less than that of diabetes (11,791 naira or US $143). The cost of antipsychotic drugs accounts for 52.8% of the cost of schizophrenia; insulin injections accounted for 92.8% of the total cost of diabetes. Patients with schizophrenia and their relatives suffered significantly more loss of working days. Cost of illness was not significantly correlated with age and duration of illness. CONCLUSIONS: Because of drastic currency devaluation, and lack of disability benefits and nursing homes, the findings contrast with Western reports where cost of drugs constitutes 2-5%, and indirect costs constitute over 50% of the total cost of schizophrenia. PMID- 9373428 TI - Mental disorders among the community-dwelling elderly in Dublin. AB - BACKGROUND: The prevalence of mental disorders among the community-dwelling elderly in the catchment area of a psychiatry for the elderly service in Dublin was determined. METHOD: A sample of 1232 individuals aged 65 years and over, identified from general practitioner practice lists, was interviewed using the Geriatric Mental State-AGECAT package. RESULTS: Depression and organic disorder occurred with prevalences of 10.3 and 4.1%, respectively. Depression diagnostic cases had comorbid anxiety at case level in 17.3% and at sub-case level in a further 59.9%. Organic diagnostic cases had comorbid depressive or anxiety symptoms, at case or sub-case level, in 32%. CONCLUSIONS: Depression is the most common mental disorder among the elderly in Dublin. The frequency of anxiety symptoms in the presentation of depression may be a factor in the under-diagnosis or misdiagnosis of depression in the community-dwelling elderly. Comorbid anxiety and depression in organic disorder may represent treatable symptoms. PMID- 9373429 TI - Subjective memory complaints in the elderly: depressive symptoms and future dementia. AB - BACKGROUND: Population studies indicate that subjective memory complaints by elderly people are correlated with cognitive performance. These complaints have some predictive power regarding the development of dementia. The present study attempted to replicate this finding, and investigated which variables determine subjective memory complaints. METHOD: Participants in the Amsterdam Study of the Elderly (n = 2114; 65-84 years of age), who were not demented and had a normal MMSE score (> 23) at baseline, were re-examined after four years. Subjective complaints were measured using a previously developed scale. Dementia and depression were measured using the Geriatric Mental State Schedule (GMS). Premorbid intelligence was measured by the Dutch Adult Reading Test (DART). RESULTS: Memory complaints at baseline contributed a small but significant amount of diagnostic information with respect to the prediction of future dementia. Depressive symptoms at baseline had no predictive value when these memory complaints were accounted for. Subjective memory complaints were associated with depression, baseline MMSE score, and premorbid intelligence. CONCLUSIONS: Subjective memory complaints are not just secondary to depression, but in part reflect realistic self-observations of cognitive decline. PMID- 9373430 TI - Cognitive deficits in patients suffering from chronic fatigue syndrome, acute infective illness or depression. AB - BACKGROUND: Patients with chronic fatigue syndrome (CFS) report neuro psychological symptoms as a characteristic feature. We sought to assess cognitive performance in patients with CFS, and compare cognitive performance and subjective workload experience of these patients with that of two disease comparison groups (non-melancholic depression and acute infection) and healthy controls. METHOD: A computerized performance battery employed to assess cognitive functioning included tests of continuous attention, response speed, performance accuracy and memory. Severity of mood disturbance and subjective fatigue were assessed by questionnaire. RESULTS: All patient groups demonstrated increased errors and slower reaction times, and gave higher workload ratings than healthy controls. Patients with CFS and non-melancholic depression had more severe deficits than patients with acute infection. All patient groups reported more severe mood disturbance and fatigue than healthy controls, but patients with CFS and those with acute infection reported less severe mood disturbance than patients with depression. CONCLUSIONS: As all patients demonstrated similar deficits in attention and response speed, it is possible that common pathophysiological processes are involved. The differences in severity of mood disturbance, however, suggest that the pathophysiological processes in patients with CFS and acute infection are not simply secondary to depressed mood. PMID- 9373431 TI - DSM-IV and ICSD-90 insomnia symptoms and sleep dissatisfaction. AB - BACKGROUND: The complex nature of insomnia and its relationship with organic and mental disorders render diagnosis problematic for epidemiologists and physicians. METHOD: A representative UK sample (non-institutionalised, > 14 years old) was interviewed by telephone (n = 4972; 79.6% participation rate) with the Sleep-EVAL system. Subjects fell into three groups according to presence of insomnia symptom(s) and/or sleep dissatisfaction. RESULTS: Insomnia symptoms occurred in 36.2% of subjects. Most of these (75.9%), however, reported no sleep dissatisfaction. In comparison, those also with sleep dissatisfaction had higher prevalence of sleep and mental disorders and longer duration of insomnia symptoms, and were more likely to take sleep-promoting medication, dread bedtime, and complain of light sleep, poor night-time sleep and daytime sleepiness. CONCLUSIONS: Insomnia sufferers differ as to whether they are satisfied or dissatisfied with sleep. Although insomnia symptoms are common in the general population, sleep disturbances among sleep-dissatisfied individuals are more severe. Sleep dissatisfaction seems a better indicator of sleep pathology than insomnia symptoms. PMID- 9373432 TI - Four-year remission of transsexualism after comorbid obsessive-compulsive disorder improved with self-exposure therapy. Case report. AB - BACKGROUND: There has been no report of comorbid transsexualism and obsessive compulsive disorder (OCD) or of their differential course over follow-up. METHOD: Such comorbidity and follow-up are documented in a case report. RESULTS: A man who had been transsexual and homosexual since early adolescence developed severe OCD at age 40 as he became depressed when his mother, to whom he was very close, died. Two years later he was referred for his OCD. He refused treatment for his transsexualism. As his OCD and mood improved with self-exposure therapy, his transsexualism and homosexuality remitted also. Four years later depression and transsexualism recurred and remained to six-year follow-up despite full remission in OCD continuing throughout. CONCLUSIONS: The sequence is like that in other cases in whom unusual sexual behaviour remitted for years after comorbid disorders improved with various treatments, or after circumstances changed. PMID- 9373433 TI - Confidential inquiry into suicide and homicide by people with mental illness. PMID- 9373434 TI - Psychiatry and the church. PMID- 9373435 TI - Paroxetine withdrawal syndrome in a neonate. PMID- 9373436 TI - Subjective quality of life in schizophrenia. PMID- 9373437 TI - Chronic fatigue syndrome. PMID- 9373439 TI - Sleep disturbance and Huntingdon's disease. PMID- 9373438 TI - Psychological consequences of road accidents in children and adolescents. PMID- 9373440 TI - Risperidone-induced leucopenia and neutropenia. PMID- 9373441 TI - Anxiety and depression in asylum-seekers. PMID- 9373442 TI - How hairy are hirsute women? PMID- 9373443 TI - Final height in non-growth hormone deficient children treated with growth hormone. The Italian Multicentre Study Group. AB - OBJECTIVE: To evaluate the final height of nongrowth hormone deficient (N-GHD) children treated with growth hormone (GH). DESIGN: Multicentre retrospective study. PATIENTS: 71 (54M/17F) N-GHD children (peak GH after pharmacological stimulation > 14-24 mU/l) who had been treated for 4.19 +/- 0.14 years with GH (0.69 +/- 0.02 IU/kg/week). MEASUREMENTS: Height (H) and height velocity (HV) expressed as standard deviation score (SDS) for chronological age (CA) and bone age (BA), BA/CA ratio, and predicted adult height (PAHSDS) were evaluated before and during treatment, and at each pubertal stage. Target height (TH), and final height (FH) were also calculated, and expressed as SDS. RESULTS: In the whole group, HSDS for CA increased significantly after the first year on GH, and remained significantly increased for 4 years. This did not occur to HSDS for BA, owing to a significant increase in BA/CA after the first year of therapy. In addition, this increase coincided with stages 4 and 5 of puberty. HVSDS for CA and BA also increased significantly after the first year of treatment, and remained significantly elevated for 4 years. PAHSDS did not change significantly during treatment. FHSDS (-1.69 +/- 0.07) was similar to PAHSDS (-1.6 +/- 0.12) and target height (THSDS) (-1.46 +/- 0.08). FHSDS was > or = THSDS in 36.6% of the patients, and > or = initial PAHSDS in 34.5%. Male patients were subdivided into 2 groups (A and B). Patients in Group A (n = 26) started treatment at puberty, while group B (n = 28) consisted of subjects who started therapy during prepubertal years. Height, height velocity and predicted adult height showed the same pattern as in the whole group, in each subgroup. BA/CA advanced significantly in group A after the second year on GH and in group B, after at least 3 years of therapy. FHSDS, THSDS, and PAHSDS were similar in both groups ( 1. 7 +/- 0.13, -1.29 +/- 0.2 and -1.39 +/- 0.15 in group A and -1.48 +/- 0.11, 1.85 +/- 0.15 and -1.36 +/- 0.12 in group B, respectively). However, in group B (prepubertal), FHSDS was > or = initial PAHSDS in 60% of the patients and > or = THSDS in 40.7%, while in group A (pubertal), FHSDS was > or = initial PAHSDS only in 22.7% of the patients and > or = THSDS in 34.6%. FHSDS was found to be correlated with THSDS, PAHSDS at the onset of treatment, and after 1 year of treatment. The age at the beginning of puberty, and the duration of puberty were appropriate in all groups. CONCLUSIONS: GH treatment was effective in increasing height velocity of short non-GH-deficient children, but final height was not definitely improved with respect to initial predicted adult height. PMID- 9373445 TI - Corticotrophic macroadenoma of the pituitary associated with hypoadrenalism. PMID- 9373446 TI - Probability in practice in the diagnosis of Cushing's syndrome. PMID- 9373447 TI - Glucoregulatory disorders in school refusal students. AB - OBJECTIVES: Our previous studies demonstrated autonomic nervous system disorders and cerebral blood hypoperfusion in school refusal students with underlying emotional distress due to fear or anxiety associated with school attendance. Because severe stress is known to affect glucoregulatory metabolism, this study used the oral glucose tolerance test (OGTT) to measure glucose metabolism in school refusal students. DESIGN: A three-hour OGTT was performed. In preparation for the test, students fasted overnight. After a fasting blood sample was drawn, students were given solutions containing a predetermined amount of glucose based on their body weight (1.75 g/kg to a maximum 75 g). After glucose ingestion, blood samples were drawn at 30, 60, 90, 120, 150, and 180 mm to measure blood glucose (BG), immunoreactive insulin (IRI), pancreatic glucagon (IRG) and growth hormone (GH) levels. BG levels, IRI response, cumulative BG (sigma BG), cumulative IRI (sigma IRI), insulin/glucose ratio (delta IRI/delta BG), and insulinogenic index (sigma IRI/sigma BG) were then compared to previously reported normal control data. As an index of emotional difficulties, the self rating depressive scale (SDS) was carried out. PATIENTS: Eighty-one school refusal students (40 males and 41 females), 11-19 years of age (14.8 +/- 2.1), were studied. Their school refusal periods ranged from one month to eight years. All students were within -15 to +20% (-0.04 +/- 8.6) of ideal body weight. MEASUREMENTS: BG levels were determined using a glucose oxidase reaction method. Serum hormones were measured by radioimmunoassay. RESULTS: BG levels at all OGTT time intervals and sigma BG were significantly higher in school refusal students than the normal control data (sigma BG: 39.5 +/- 4.4 vs 33.3 +/- 3.4 mmol/l P < 0.001). Although the insulin response was abnormally low relative to the prevailing hyperglycaemia (sigma IRI/ sigma BG: subjects vs control = 232 +/- 129 vs 375 +/- 271, P < 0.01), normal beta cell secretory ability was speculated (sigma IRI: subjects vs controls = 2805 +/- 1274 vs 2523 +/- 1219 pmol/l). This suggests a relative suppression of insulin secretion. A paradoxical increase of GH was observed in 19 students after glucose ingestion. CONCLUSIONS: Glucoregulatory disorders observed in school refusal students may be caused by emotional distress. Multiple factors including autonomic nervous system disorders, derangement of neuropeptides in the hypothalamus, and hormonal imbalances may also affect glucoregulatory metabolism, predisposing these students to hyperglycaemia. We speculate that the glucoregulatory system compensates for decreased blood flow to the brain by increasing blood glucose concentrations, thereby providing sufficient glucose as the primary energy source used during normal brain metabolism. PMID- 9373448 TI - Bone loss in hyperthyroid patients and in former hyperthyroid patients controlled on medical therapy: influence of aetiology and menopause. AB - OBJECTIVE: The effect of hyperthyroidism on osteoporosis risk and its reversal after control of hyperthyroidism remains somewhat controversial. We assessed the values of bone mineral density in hyperthyroid patients and in former hyperthyroid patients euthyroid on medical therapy, as well as the influence of aetiology and menopause upon bone mass. DESIGN: The values of bone mineral density in hyperthyroid patients (active) and former hyperthyroid patients euthyroid on medical therapy (controlled), were compared, together with data from our control group and from the Spanish reference population. We also compared the values of bone mineral density in patients with Graves' disease with those in patients with toxic nodular goitre and assessed the influence of the menopause. PATIENTS: We studied 127 consecutive hyperthyroid patients (age 41 +/- 16 years; 110 females, 17 males; 102 Graves' disease and 25 toxic nodular goitre); 78 were active (group A) and 49 controlled on medical therapy (carbimazole, mean time of euthyroidism 7.5 +/- 9.1 months; group B). We also studied 43 healthy subjects (age 40 +/- 14 years; 41 females, two males; group C). MEASUREMENTS: Bone mineral density was assessed by dual X-ray absorptiometry at lumbar spine (L2-L4), femoral neck and Ward's triangle. Data were expressed as g/cm2 and as a Z score (SD vs Spanish reference population adjusted by age and sex). Blood was obtained to measure the levels of free T4, TSH and TSH receptor antibody. RESULTS: Patients with active hyperthyroidism showed a generalized reduction in axial bone mineral density in comparison with both the control group and the reference population, whereas former hyperthyroid patients showed partial recovery of bone mass in lumbar spine and Ward's triangle. Mean Z scores at lumbar spine, femoral neck and Ward's triangle were: -0.92, -0.79 and -0.89 in group A; -0.74, -0.23 and -0.44 in group B and 0.18, 0.09 and 0.36 in group C, respectively. No differences were found between bone mineral density values from patients with Graves' disease and those with toxic nodular goitre, nor between pre and postmenopausal hyperthyroid women once adjusted by age and sex. CONCLUSIONS: Our data suggest that hyperthyroid patients show a generalized reduction of bone mass in the axial skeleton and that only partial recovery is present in former hyperthyroid patients after a mean of 7.5 months of biochemical euthyroidism. This recovery is insufficient to normalize the bone density in lumbar spine and Ward's triangle, although femoral bone mass was not different from that of the control group. The extent and degree of hyperthyroid bone disease surpass the effects of the menopause on the bone mass. The aetiology of hyperthyroidism does not seem to play any role in the severity of hyperthyroid bone disease. PMID- 9373449 TI - Immunoreactive amino-terminal pro-brain natriuretic peptide (NT-PROBNP): a new marker of cardiac impairment. AB - OBJECTIVE: Human brain natriuretic peptide-32 (BNP) (i.e. proBNP(77-108)), the mature form of BNP and secreted predominantly by the cardiac ventricle, is formed from a high molecular weight precursor, proBNP(1-108). We have recently identified the aminoterminal form proBNP(1-76) (NT-proBNP) in human plasma but its source, metabolism and production in circulatory disorders are unknown. We have investigated the relationship between immunoreactive (IR) NT-proBNP and BNP 32 in normal and hypertensive subjects and in patients with cardiac impairment, as well as the regional plasma concentrations in patients undergoing routine cardiac catheterization. DESIGN AND PATIENTS: Plasma hormone measurements were made in 26 normal subjects, 20 subjects with untreated mild hypertension and 111 treated patients with a history of coronary heart disease and documented cardiac impairment (left ventricular election fraction (LVEF) < 45% (mean 29%); 25 NYHA Class I, 65 Class II and 21 Class III). Regional blood sampling from the femoral artery, femoral vein, renal vein and coronary sinus was undertaken in 14 patients presenting for left and right cardiac catheterization studies in the course of standard investigation for a range of cardiac disorders. MEASUREMENTS: Plasma samples were assayed for IR NT-proBNP and IR BNP-32 (and atrial natriuretic peptide (ANP) in the regional blood samples). In the patients with cardiac impairment, LVEF was determined by gated radionuclide ventriculography, exercise capacity was measured using a modified Naughton multistage protocol and creatinine clearance was calculated from plasma creatinine, age and weight. In the regional study, extraction ratios across the kidney and lower limb (and step ups across the heart) were calculated from plasma peptide concentrations. RESULTS: In normal subjects mean IR NT-proBNP levels (10.8 +/- 1.3 pmol/L) were similar to levels of IR BNP-32 (9.7 +/- 0.5 pmol/L). In hypertensive patients the levels of IR NT-proBNP and IR BNP-32 tended to be higher than but were not significantly different from normal subjects. Both IR NT-proBNP and IR BNP-32 were raised in NYHA Classes I, II and III compared with normals (P < 0.001 for all) with higher levels of both BNP forms seen with increasing cardiac impairment. The levels of IR NT-proBNP were greater than IR BNP-32 in all NYHA Classes (P < 0.001) for all). Overall, the levels of IR NT-proBNP (129 +/- 12 pmol/L) were 4-fold higher than concomitant BNP-32 levels (29 +/- 2 pmol/L). Multivariate analysis showed that LVEF, exercise test time and creatinine clearance were independent predictors of IR NT-proBNP. In all study groups, the levels of IR NT-proBNP and IR BNP-32 levels were highly correlated. Regional plasma sampling showed similar step-ups in IR NT-proBNP and IR BNP-32 levels across the heart, together with similar extraction of both BNP forms across the kidney and lower limb. For both BNP forms, these changes across tissues were significantly less than for ANP. CONCLUSIONS: Plasma levels of immunoreactive amino terminal-proBNP are raised in cardiac impairment, including NYHA Class I, and rise with increasing cardiac decompensation. Metabolism and tissue uptake of immunoreactive amino terminal-proBNP and immunoreactive BNP-32 appear similar. In cardiac impairment the proportional and absolute increment above normal levels of the aminoterminal BNP peptide exceeds that for BNP-32 and suggest that amino terminal-proBNP may be a more discerning marker of early cardiac dysfunction than BNP-32. PMID- 9373450 TI - Inhaled beclomethasone dipropionate suppresses the hypothalamo-pituitary-adrenal axis in a dose dependent manner. AB - OBJECTIVE: Little is known about the dose-response relationship of potential, unwanted, effects of inhaled beclomethasone (BDP) on the hypothalamo-pituitary adrenal (HPA) axis, particularly in nonspecialist clinic settings. The purpose of our study was to investigate the dose-response relationship of inhaled BDP on the HPA axis in a general practice patient population. We also explored the optimal testing strategy in this population and correlated effects of inhaled BDP on the HPA axis with other systemic corticosteroid side effects. PATIENTS AND DESIGN: Controlled observational study employing 21 patients on inhaled BDP recruited from general practice, with minimal past and no present exposure to other corticosteroids, and 21 age and gender-matched controls. MEASUREMENTS: Twenty four-hour urinary free cortisol excretion (UFC), serum cortisol before and 30 minutes after injection of 1 microgram and 250 micrograms of tetracosactrin, serum IGF-I and serum osteocalcin were measured. BDP use was estimated by inhaler weighing and prescription count. RESULTS: In subjects on inhaled BDP, 24-hour UFC (P < 0.008), serum cortisol 30 minutes after 250 micrograms tetracosactrin (P < 0.05) and the serum cortisol rise after 250 micrograms tetracosactrin (P < 0.04) were significantly lower when compared with controls. Measurements of HPA function correlated inversely with BDP dose estimated by inhaler weighing (all P < 0.03). Serum IGF-I and osteocalcin levels did not differ. CONCLUSIONS: We have demonstrated hypothalamo-pituitary-adrenal axis suppression in nonspecialist clinic asthma patients on moderate to large doses of inhaled beclomethasone dipropionate. When accurate measurements of inhaled steroid dose are used, there is an exponential relationship between dose and hypothalamo-pituitary-adrenal axis suppression. There appears to be no 'safe' threshold, and around 15% of patients may have clinically significant suppression. However, the significance of hypothalamo-pituitary-adrenal axis suppression as a marker for concomitant corticosteroid effects on other organ systems remains uncertain. PMID- 9373451 TI - Influence of residual C-peptide secretion on nocturnal serum TSH peak in well controlled diabetic patients. AB - OBJECTIVE: Several alterations in hypothalamo-pituitary-thyroid (HPT) function have been described in diabetes mellitus and have been attributed to metabolic decompensation. The present study was performed in order to establish whether residual endogenous insulin secretion in patients with insulin-dependent diabetes mellitus (IDDM) may play a role in the control of HPT function. DESIGN: The nocturnal (2230 h-0200 h) serum TSH surge, the TSH response to TRH (200 microgram as an i.v. bolus) and serum free thyroid hormone levels were evaluated in C peptide positive (CpP) (subjects with residual detectable endogenous pancreatic beta-cell activity) and C-peptide negative (CpN) patients both before and after optimization of metabolic status by 3 days of treatment with continuous subcutaneous insulin infusion, and in normal controls. TSH response to TRH and serum free thyroid hormone levels were assessed in the morning. SUBJECTS: Twenty male diabetic patients hospitalized to achieve a better control of hyperglycaemia were subdivided into 10 CpP (age: 33 +/- 1.5 years (mean +/- SE); body mass index (BMI): 22.6 +/- 0.3) and 10 CpN (age: 32 +/- 1.7 years; BMI: 22.5 +/- 0.4) patients. Nine normal men (age: 34.0 +/- 1.2 years; BMI: 23.1 +/- 0.4) served as controls. MEASUREMENTS: The nocturnal serum TSH peak was measured by dividing the highest night-time TSH value by the next morning TSH value and then multiplying by 100. Serum TSH levels were measured in samples taken just before (time 0) and 30 minutes, after TRH administration. Serum free thyroid hormone levels were measured in samples taken at time 0 of the TRH test. RESULTS: Before improvement of hyperglycaemia, CpP and CPN patients showed similar alterations in HPT function; i.e. serum free T3 levels and TSH responses to TRH were lower than normal; the nocturnal TSH surge was absent. Correction of hyperglycaemia normalized all examined HPT parameters in CpP diabetics, whereas normalization in serum free T3 levels and pituitary TSH responsiveness to TRH in CpN patients was not accompanied by restoration of the nocturnal TSH peak. CONCLUSIONS: These data indicate that the absence of residual pancreatic beta-cell function in patients with insulin-dependent diabetes mellitus is associated with neuroendocrine dysfunction in the regulation of circadian TSH secretion, which is not reversible after restoration of good glycaemic control. PMID- 9373452 TI - An analysis of testosterone implants for androgen replacement therapy. AB - OBJECTIVE: To review 13 years of experience using fused crystalline testosterone implants for androgen replacement therapy in order to identify pattern of usage (including continuation rates) and adverse events emerging during therapy and factors associated with adverse events including implant extrusions. DESIGN: Retrospective review of prospectively collected data on characteristics of patients and implant procedures performed as well as adverse events reported during routine follow-up. PATIENTS: Over 13 years 973 implant procedures using fused crystalline testosterone implants were performed in 221 men. MEASUREMENTS: Continuation rates and adverse events such as extrusions, bleeding, infection or others were recorded and analysed in relationship to characteristics of the patient and the implant procedure performed. RESULTS: Overall rate of adverse events (108/73, 11.1%) was significantly related to increased numbers of implants (4.2 +/- 0.1 vs 4.0 +/- 0.03, P = 0.031) and higher levels of physical activity at work (P = 0.030). The most common adverse effect was extrusion (83/973, 8.5%) which was related to occupational classification (P = 0.033) and increasing work activity (P = 0.044) and occurred more frequently than by chance in multiple (16 vs 3.3 expected) rather than single (65 vs 76.1 expected) episodes. Bleeding (22/973, 2.3%) was significantly associated with an increased number of implants (4.5 +/- 0.2 vs 4.0 +/- 0.03, P = 0.020) but even in the worst cases (3/22) it was of minor clinical importance. Infection was rare (6/973, 0.6%) but occurred more among thinner men. The overall continuation rate was 92.7% increasing from 86% after the first implantation to > 99% after the tenth implant. CONCLUSIONS: This study demonstrates the very satisfactory clinical acceptability of testosterone pellet implants for androgen replacement therapy within a single unit with experienced operators. The only regular adverse effect is extrusion, which may be related to mechanical factors such as habitual work activity but also possibly procedural factors. Other adverse effects such as bleeding, infection and fibrosis were rare. An improved method of implant delivery would enhance this old but durable technology. PMID- 9373453 TI - Serum LH concentrations in hypogonadal men during transdermal testosterone replacement through scrotal skin: further evidence that ageing enhances testosterone negative feedback. The Testoderm Study Group. AB - OBJECTIVE: The present study was designed to explore further the mechanism for the decline in androgen production as men age by studying the influence of ageing on testosterone negative feedback control of gonadotrophin secretion. DESIGN: Circulating testosterone, dihydrotestosterone, oestradiol, SHBG and LH concentrations were measured during long-term treatment of men with primary hypogonadism using transdermal testosterone via scrotal skin. PATIENTS: Results were compared in 12 hypogonadal men below age 40 years (34 +/- 1.1 years; mean +/ SEM), 13 middle-aged men, aged 51 +/- 2.2 years, and 10 men age 64 years or older (68 +/- 1.4 years). RESULTS: During the course of therapy, circulating LH levels were suppressed 48% (F = -2.42, P = 0.018) from 19.6 +/- 6.0 IU/I at baseline to 10 +/- 7.7 IU/I during month 15 in elderly men. By contrast, LH levels were unchanged (F = 0.31; P = 0.97) in young men (20.3 +/- 7.4 IU/I at baseline and 17.7 +/- 14.9 IU/I during treatment month 15). Intermediate results were observed in middle-aged men in whom LH levels declined slightly (F = 1.34; P = 0.24). Transdermal testosterone treatment produced similar circulating testosterone levels (F = 1.49; P = 0.24) and oestradiol levels (F = 0.60; P = 0.42) in elderly and young men. Mean plasma DHT levels were approximately 20% higher (F = 9.91; P = 0.01) during treatment in elderly men overall mean values of 8.03 +/- 0.37 nmol/l) than in young men (6.68 +/- 0.08 nmol/l). When total DHT was adjusted for higher plasma SHBG levels in elderly men, the free DHT index during treatment was similar (F = 0.23; P = 0.64) in both groups. CONCLUSIONS: These data provide further evidence that the set point for androgen negative feedback control of gonadotrophin accretion in men is altered by ageing. Taken together with previous findings, these results provide a potential explanation for the unchanged or slightly increased plasma LH levels and reduced testosterone production characteristic of elderly men. Accordingly, ageing-associated Leydig cell insufficiency leads to a decline in testosterone production, but circulating LH levels do not rise appropriately because the set-point for negative feedback is decreased. PMID- 9373454 TI - Increased incidence of neoplasia in females with acromegaly. AB - OBJECTIVE: Some studies have indicated an increased incidence of neoplasia, particularly breast and colon, in acromegaly. We have determined the incidence of benign and malignant neoplasms in an Australian population of patients with acromegaly. DESIGN: Retrospective review, with comparison against cancer data for the local population obtained from a State Cancer Registry. PATIENTS: Fifty patients with documented acromegaly. RESULTS: There were 7 cases of malignancy (2 in men, 5 in women) in the period of follow-up (435 patient years). With logistic regression analysis, there was a relative risk of malignancy, of 1.2 (95% confidence interval 0.31-5.0) for men (P = 0.8) and 4.3 (95% confidence interval 1.7-10.5) for women (P = 0.001), when compared to the local population. There were 2 cases of breast and renal carcinoma, and one each of prostatic, colonic and parotid carcinoma. Of the most common benign tumours 35% of patients had thyroid nodules, 10% had colonic polyps and 6% had nasal polyps. CONCLUSION: The incidence of malignancy was found to be increased in female patients with acromegaly in this series. Routine screening procedures for malignancy, particularly in female patients, should therefore be considered. PMID- 9373455 TI - Expression of growth hormone receptor by peripheral blood lymphocytes in children: evaluation in clinical conditions of impaired growth. AB - OBJECTIVE: It is widely accepted that the haematopoietic system is a target of growth hormone action and that GH may act as a lymphokine. The expression of GH receptors (GHR) on human peripheral blood lymphocytes (PBL) has been reported previously in adult donors by dual fluorochrome flow cytometry. The aim of this study was to apply the cytofluorimetric method to the analysis of GHR expression on PBL in various human conditions characterized by different patterns of growth due to age or physiopathological conditions. SUBJECTS AND DESIGN: PBL from 38 normal (control) subjects (7 newborns, 18 prepubertal children, 13 adults) were studied in order to provide age-related physiological data. Twenty-two short children (18 with idiopathic short stature, 4 with Ullrich-Turner syndrome) were studied to determine the expression of GHR in conditions of impaired longitudinal growth which may or may not require GH treatment. METHODS: Analysis was performed using a fluorescein isothiocyanate (FITC)-conjugated antibody specific for the GHR (mAb263) and phycoerythrin (PE)-anti CD2 (T and natural killer cells) or PE anti CD2 (B cells) in dual fluorochrome flow cytometric assays. Results were expressed as mean fluorescent intensity (MFI). RESULTS: Adult CD2+ coils exhibited a significantly higher GHR expression (MFI 347 +/- 40) than that expressed in children and newborns (MFI 285 +/- 36 and 299 +/- 41, respectively, P < 0.001). A significantly increased expression of GHR on CD2+ cells was also found in short children (MFI 330 +/- 42 vs 285 42- 36, respectively; P < 0.002), whereas Ullrich-Turner syndrome patients did not show any difference from their age and gender matched controls (254 +/- 52 and 288 +/- 40, respectively). A negative relationship was found between GHR expression on CD2+ cells and height SDS (r - 0.54, P < 0.0001) or BMI (r - 0.4, P < 0.015) in controls and short children, independent of their GH secretory status. Expression of GHR and CD20+ cells was higher than that expressed on CD2+ cells in all subjects. No appreciable differences were found in the MFI levels of GHR expression on CD20+ cells either among the different age group controls or between short children or Ullrich-Turner syndrome patients. A significant downregulation of expression was shown in CD20+ (P < 0.008) but not CD2+ cells after 6 months of GH treatment in 6 short children who had a poor response to GH provocative tests. CONCLUSIONS: GH receptor expression on immune cells in non-syndromic short children appears to be inversely related to the linear growth expression and BMI of the subjects, contrary to findings with hepatic derived serum GHBP. This finding may reflect alternate exon usage in lymphoid cells, and indicates that GH has a distinctive role in the immune system. PMID- 9373456 TI - Mortality and morbidity in transsexual subjects treated with cross-sex hormones. AB - OBJECTIVE: The optimum steroid hormone treatment regimes for transsexual subjects has not yet been established. We have investigated the mortality and morbidity figures in a large group of transsexual subjects receiving cross-sex hormone treatment. DESIGN: A retrospective, descriptive study in a university teaching hospital. SUBJECTS: Eight hundred and sixteen male-to-female (M-->F) and 293 female-to-male (F-->M) transsexuals. INTERVENTIONS: Subjects had been treated with cross-sex hormones for a total of 10,152 patient-years. OUTCOME MEASURES: Standardized mortality and incidence ratios were calculated from the general Dutch population (age- and gender-adjusted) and were also compared to side effects of cross-sex hormones in transsexuals reported in the literature. RESULTS: In both the M-->F and F-->M transsexuals, total mortality was not higher than in the general population and, largely, the observed mortality could not be related to hormone treatment. Venous thromboembolism was the major complication in M-->F transsexuals treated with oral oestrogens and anti-androgens, but fewer cases were observed since the introduction of transdermal oestradiol in the treatment of transsexuals over 40 years of age. No cases of breast carcinoma but one case of prostatic carcinoma were encountered in our population. No serious morbidity was observed which could be related to androgen treatment in the F-->M transsexuals. CONCLUSION: Mortality in male-to-female and female-to-male transsexuals is not increased during cross-sex hormone treatment. Transdermal oestradiol administration is recommended in male-to-female transsexuals, particularly in the population over 40 years in whom a high incidence of venous thromboembolism was observed with oral oestrogens. It seems that in view of the deep psychological needs of transsexuals to undergo sex reassignment, our treatment schedule of cross-sex hormone administration is acceptably safe. PMID- 9373457 TI - Psychological distress in patients with hyperprolactinaemia. AB - OBJECTIVE: In addition to the physical symptoms of galactorrhoea and amenorrhoea, hyperprolactinaemia in women is also reported to be associated with psychological symptoms. Previous studies have found an increased incidence of depression, anxiety and hostility in female patients with hyperprolactinaemia. In this study, psychological symptoms were assessed in a large population of patients and symptom scores were compared between patients with definite evidence of pituitary adenoma on high-resolution CT scanning and those without, who were presumed to have idiopathic or 'functional' hyperprolactinaemia. DESIGN: Postal survey: population-control study of female patients with hyperprolactinaemia. PATIENTS: Sixty-five women with hyperprolactinaemia were compared with a control group of 26 women with normoprolactinaemic pituitary disease (acromegaly or nonfunctioning pituitary adenoma). The hyperprolactinaemic patients were subdivided according to whether a pituitary adenoma was visible on high-resolution CT scanning (39 patients) or whether they had normal CT scans, in which case they were categorized as having idiopathic or 'functional' hyperprolactinaemia (26 patients). MEASUREMENTS: Patients were sent 2 questionnaires, the Hospital Anxiety and Depression (HAD) Scale and the 90-item Symptom Checklist (SCL-90), to assess psychological wellbeing. RESULTS: Overall, 54% of hyperprolactinaemic patients were found to have definite or borderline anxiety as judged by HAD scores, compared with 27% of normoprolactinaemic control patients. Those with normal CT scans were significantly more likely to have definite or borderline anxiety (73% of patients) than those with CT evidence of a pituitary tumour causing their hyperprolactinaemia (41%, P < 0.003), despite similar levels of serum prolactin. A similar increased proportion of hyperprolactinaemic patients scored highly on the anxiety component of the SCL-90, although mean scores were not different from controls. No differences were seen in scores for depression, but both subgroups of hyperprolactinaemic patients scored more highly than controls for hostility on the SCL-90 questionnaire. CONCLUSION: These findings confirm the presence of significant anxiety in a proportion of women with hyperprolactinaemia. Hyperprolactinaemic women with no abnormality on CT scans displayed more psychological distress than those with definite pituitary microadenomas. These results may provide insight into the pathogenesis of 'functional' hyperprolactinaemia. PMID- 9373458 TI - Anisomycin and verapamil influence the action of progesterone on regulation of term human myometrial contractile activity. AB - OBJECTIVE: Progesterone has been shown to have both stimulatory and inhibitory effects on term human myometrial contractile activity. The mechanisms involved in this action of progesterone are still poorly understood. DESIGN: Myometrial tissues were obtained from the lower uterine segment at elective Caesarean section of 30 term pregnant women. The contractile activity of muscle strips was measured by a superfusion technique and protein synthesis evaluated by [3H] leucine incorporation. RESULTS: [3H]-leucine incorporation into term myometrial strips was not affected by progesterone (10 mumol/l), but was markedly reduced by the protein synthesis inhibitor anisomycin (P < 0.05). However, progesterone increased frequency and tonus of contractions and reduced the activity-area of contractions (P < 0.01). Anisomycin (100 mumol/l) did not change these effects or the spontaneous contractile activity. Removal or extracellular Ca2+ or addition of the L-type calcium channel blocker verapamil prevented the spontaneous as well as the progesterone-induced contractions, but had less pronounced effects on contractions initiated by oxytocin. CONCLUSION: The results indicate that the actions of progesterone on term myometrial contractile activity occur without protein synthesis and that increased Ca2+ influx or decreased outward transport of Ca2+ may play a possible role) PMID- 9373460 TI - Does growth hormone treatment increase chromosomal abnormalities? AB - OBJECTIVE: The relationship between growth hormone (GH) therapy and malignancy, including leukaemias, remains controversial. In order to study this possible relationship further, we have investigated whether GH treatment induces chromosomal abnormalities in peripheral blood lymphocytes. DESIGN: Open, prospective study in a University Hospital to examine peripheral blood mononuclear cells in subjects with GH-deficiency (GHD) before and during GH treatment. SUBJECTS: Twelve idiopathic GHD patients, aged 1.8-12.5 years, were evaluated before and after 3, 6 and 12 months of GH therapy (0.6 IU/kg per week subcutaneously). Two additional GHD patients, aged 16.6 and 18 years, were studied 1 year after long-term GH therapy had been discontinued, and 12 age matched healthy subjects were evaluated as controls. METHODS: We examined the incidence of chromosome and chromatid breaks, fragments, structural rearrangements and aneuploidies in 100 metaphases for each blood sample. A total of 5300 cells was analysed in the 14 patients. RESULTS: The proportion of cells with chromatid and chromosome breaks ranged from 0% to 6% in patients before treatment and from 1% to 5% in controls. During GH therapy the incidence of aneuploid metaphases ranged from 0% to 7% and was comparable with values observed in controls. Chromosomal loss and gain was random. CONCLUSIONS: We observed no increase in chromosomal abnormalities in GH-treated patients when compared with age-matched healthy controls. PMID- 9373459 TI - Effects of excess iodine administration on thyroid function in euthyroid patients with a previous episode of thyroid dysfunction induced by interferon-alpha treatment. AB - OBJECTIVE: To determine the effects of pharmacological quantities of iodide (SSKI) on thyroid function in euthyroid patients previously treated with recombinant interferon-alpha (rIFN-alpha) for chronic viral hepatitis B and C (HCV), a cytokine which may induce thyroid dysfunction. DESIGN: Thyroid function tests were carried out in 16 euthyroid patients, 8 of whom had previously developed thyroid dysfunction during rIFN-alpha therapy for HCV, before, during and after the administration of 10 drops of saturated solution of potassium iodide (SSKI) (approximately 350 mg iodide). PATIENTS: All 16 patients had been treated in the past with rIFN-alpha for HCV. Eight patients had developed rIFN alpha induced abnormalities in thyroid function (5 inflammatory thyrotoxicosis, 1 Graves' disease, and 2 impaired thyroid organification of iodide) and 8 had not developed thyroid dysfunction. MEASUREMENTS: After baseline serum free T4 (FT4) and free T3 (FT3) concentrations, basal and TRH stimulated TSH concentrations, and TSH-receptor (TSH-R-Ab) and thyroid peroxidase (TPO-Ab) antibodies were measured, 10 drops saturated solution of potassium iodide (SSKI, approximately 350 mg iodide) were given daily for 60 days and the above parameters assessed during and after SSKI was discontinued. RESULTS: Five of 8 patients with a previous history of rIFN-alpha induced thyroid dysfunction developed mild iodide induced abnormalities of thyroid function (subclinical hypothyroidism (slightly elevated basal and TRH stimulated serum TSH concentrations with normal serum FT4 and FT3 concentrations) or hyperthyroidism) compared with the 8 patients who had no previous evidence of thyroid dysfunction during rIFN-alpha therapy. CONCLUSIONS: In view of the present observations, it is prudent to avoid the administration of excess iodine to euthyroid subjects with a previous episode of thyroid dysfunction during rIFN-alpha therapy, adding a new group of patients susceptible to iodine induced thyroid disease. PMID- 9373461 TI - Bone mineral density in Turner's syndrome--a longitudinal study. AB - OBJECTIVE: Osteoporosis is a recognized problem in adult women with Turner's syndrome, the aetiology of which is unclear. The aim of this study was to examine bone mineralization longitudinally in a group of girls with Turner's syndrome and to study the effect of different treatments on bone mineral density. DESIGN: A prospective observational study. PATIENTS: Eighteen girls with Turner's syndrome aged 4-17 years attending a paediatric endocrine clinic. MEASUREMENTS: Bone mineral density of the lumbar spine was assessed using dual energy X-ray absorptiometry at several time points over a 2.5-year period. RESULTS: Only one girl had evidence of a significant reduction in bone density when comparisons were made with control data related to body weight and pubertal status. No advantage was found for any form of treatment in optimizing bone mineralization. CONCLUSIONS: As there is little evidence of reduced bone mineral density in girls with Turner's syndrome there is no justification for an early introduction of oestrogen replacement during the prepubertal years. PMID- 9373463 TI - Of pills and potions. PMID- 9373462 TI - Adrenal adenoma with bilateral adrenocortical nodular change in a patient with Cushing's syndrome. AB - We report a 57-year-old male patient with adrenocorticotrophin (ACTH)-independent Cushing's syndrome and long-standing hypertension. Both abdominal computed tomographic scan and magnetic resonance imaging revealed bilateral adrenal enlargement with the presence of a tumour in the left adrenal. Marked uptake of 131I-6 beta-iodomethyl-19-norcholesterol was observed only in the left adrenal gland. Left adrenalectomy and biopsy of the right adrenal gland were subsequently performed. Histological examination revealed the presence of an adrenocortical adenoma in the left adrenal with multiple adrenocortical nodules in both left and right non-neoplastic adrenals. Peri- and intraadrenal arteries and arterioles demonstrated marked arteriosclerotic vascular changes. Immunoreactivity for several steroidogenic enzymes was present in the tumour and markedly diminished in the non-neoplastic adrenals. This patient with Cushing's adenoma is considered to have developed adrenocortical nodules in the nonneoplastic adrenal possibly as a result of localized compensatory overgrowth of adrenocortical cells in response to ischaemic changes due to arteriopathy. When examining patients with Cushing's syndrome and bilateral adrenal enlargement, the possibility of concomitant adenoma and adrenocortical nodule formation should also be considered in the differential diagnosis PMID- 9373464 TI - The Bowman Lecture. Papilloedema: 'the pendulum of progress'. PMID- 9373465 TI - Retinal changes associated with tamoxifen treatment for breast cancer. AB - PURPOSE: This study was undertaken to estimate the incidence of retinal changes and determine the prevalence of ocular toxicity associated with tamoxifen treatment in a breast cancer population. METHODS: The study was based on a population cross-sectional survey, including 290 patients taking tamoxifen from 6 months to 12 years; 274 patients were analysed. The main outcome measures were the incidence of retinal changes and visual impairment. RESULTS: The incidence of retinal changes was 0.9% (3 of 274 patients). All 3 patients were asymptomatic. The length of tamoxifen treatment ranged from 39 months to 120 months in the affected patients, with cumulative tamoxifen doses ranging from 23.7 g to 73 g. CONCLUSIONS: Retinopathy in patients receiving low doses of tamoxifen is rare and, in our study, did not result in changes in visual acuity. We found no retinopathy in patients receiving tamoxifen within the first 3 years of treatment or in patients receiving a total tamoxifen dosage of less than 23.7 g. Although retinopathy can occur in a tamoxifen-treated population, its low incidence and an associated good prognosis for vision does not merit special screening for this problem. PMID- 9373466 TI - The presence of congenital hypertrophy of the retinal pigment epithelium in a subgroup of patients with adenomatous polyposis coli mutations. AB - Patients expressing congenital hypertrophy of the retinal pigment epithelium (CHRPE) are clustered within specific families with familial adenomatous polyposis (FAP). CHRPE has been found to be dependent on the position of the mutation in the adenomatous polyposis coli (APC) gene. The significance of the CHRPE finding in view of this new evidence is discussed. PMID- 9373467 TI - Prevalence of age-related maculopathy at two points in time in an elderly British population. AB - As the demography of Western society changes, the population prevalence of diseases such as age-related macular degeneration (AMD) is expected to rise. Despite this, there remains a paucity of quality data concerning the population prevalence of AMD, the commonest cause of blindness in the elderly. PURPOSE: To report the prevalence of AMD at two points in time in an elderly population. METHOD: A geographically defined random population sample of elderly people was defined in 1980, and studied in 1982-4. In 1990, a cohort of survivors was identified. Participants underwent full ophthalmic examination with fundus photography using the same camera on each occasion. Photographs were randomly encoded and graded by two independent masked observers using the Wisconsin Age related Maculopathy Grading System. Disagreements were resolved by consensus. RESULTS: Eighty-eight survivors participated in the follow-up examinations. Of these, 82 subjects had gradable retinal photographs for both examination points in at least one eye. There were 158 pairs of images (initial and subsequent) available for analysis. The mean age was 80 years (range 77-90 years) at the initial examination, and 87 years (range 84-97 years) at the subsequent examination; 70.7% of subjects were female. Prevalence rates for the initial examination were: drusen 72.8%, drusen confluence 37.3%, degeneration of the retinal pigment epithelium (RPE) 51.3%, increased pigment 22.2%, exudative AMD 1.9% and geographic atrophy 1.9%. Rates at second examination were: drusen 62.7% drusen confluence 41.8%, RPE degeneration 72.8%, increased pigment 16.5%, exudative AMD 3.8% and geographic atrophy 3.2%. CONCLUSION: This 'double' prevalence study provides detailed data on AMD lesions at two points in time in a population-based group of elderly people. PMID- 9373468 TI - Seven year follow-up of age-related maculopathy in an elderly British population. AB - Despite age-related macular degeneration (AMD) being the commonest cause of blindness amongst the elderly in Western society, the incidence of new lesions is poorly documented and the natural history of existing disease remains ill understood. PURPOSE: To document in an elderly population the incidence of new AMD lesions and the progression of pre-existing AMD over time. METHOD: Baseline ophthalmic examinations were performed on a geographically defined random population sample of elderly people in 1982-4, and retinal photographs taken. The present study re-examined and re-photographed survivors after approximately 7 years using the same fundus camera. Photographs were randomly encoded, and independently graded for AMD features by two masked observers using the Wisconsin AMD grading system. Disagreements were resolved by review to reach a consensus. RESULTS: Eighty-two of the 88 participating survivors had photographs of gradable quality on both occasions in at least one eye. Mean age at follow-up was 87 years (range 84-97 years) and 70.7% of subjects were female. Paired photographs were available on 158 eyes, and showed important differences in drusen type, drusen area and characteristics of the retinal pigment epithelium (RPE) between initial and subsequent examinations. The 7 year incidence (and regression) of lesions was: drusen 30.6% (20.0%), RPE degeneration 54.5% (8.8%), increased pigment 11.6% (64.7%), subretinal haemorrhage 1.3%, subretinal scar/fibrin 1.3% and geographic study 1.3%. CONCLUSION: These unique population-based results provide new insight into the natural history of AMD in an elderly population. PMID- 9373469 TI - Giant retinal tears after pars plana vitrectomy. AB - Vitreous surgery is used to treat complicated vitreo-retinal pathology. Retinal tears are a serious complication of vitreous surgery. In this report, the development of giant retinal tears in four eyes after pars plana vitrectomy for posterior segment pathology is described. The pathogenesis and implications of this serious and infrequent complication are discussed. PMID- 9373471 TI - Pulsatile ocular blood flow in eyes with untreated choroidal melanoma. AB - PURPOSE: To investigate the effect of choroidal melanoma on pulsatile ocular blood flow (POBF). METHODS: Seventeen patients (10 men and 7 women) with unilateral untreated choroidal melanoma and 22 controls matched for age and sex were studied. Intraocular pressure (IOP), pulse amplitude (PA) and POBF were measured using the OBF Tonograph. In each patient, mean inter-ocular differences were analysed using the paired t-test. The correlation coefficient between tumour thickness and POBF was calculated. To assess the variation of this parameter, the coefficient of variation for three repeated readings was determined for healthy and affected eyes. RESULTS: In the control group, there was no significant difference between eyes in any parameter. In patients with melanoma, there was no significant difference in IOP and PA between affected and unaffected eyes. Mean POBF was significantly higher in affected eyes (1040 microliters min-1) than unaffected eyes (876 microliters min-1) (p = 0.003). There was no correlation between tumour thickness and absolute POBF (r = -0.24) or between tumour thickness and inter-ocular difference in POBF between affected and unaffected eyes (r = -0.17). Mean coefficient of variation of three repeated readings of POBF was 7.76% in healthy eyes and 8.97% in affected eyes. CONCLUSIONS: These findings suggest a high tumour blood flow or a global increase in choroidal blood flow in the presence of melanoma. POBF measurement may be useful in the clinical assessment of eyes with choroidal melanoma. PMID- 9373470 TI - Prophylactic argon laser retinopexy prior to removal of silicone oil: a pilot study. AB - BACKGROUND: Removal of silicone oil following successful retinal detachment surgery is usually performed in an attempt to prevent the complications of silicone oil; however, removal of the oil may result in retinal redetachment. PURPOSE: The purpose of this study was to determine whether argon laser retinopexy, 3-6 weeks prior to the removal of silicone oil, reduces the rate of retinal detachment following silicone oil removal. METHODS: A total of 31 eyes of 31 consecutive patients were followed up for a 12 month period after the removal of silicone oil. All patients had undergone retinal reattachment surgery resulting in a clinically attached retina with the absence of residual retinal traction prior to silicone oil removal. A study group of 15 of the 31 eyes received two rows of 360 degrees of peripheral argon laser retinopexy 3-6 weeks before removal of the silicone oil. The 16 eyes of the previous 16 consecutive patients, who underwent removal of silicone oil without argon laser retinopexy, were used as a control group. RESULTS: In the study group 1 of 15 eyes (6.7%) redetached following the removal of silicone oil and 4 of 16 (25%) redetached in the control group during the 12 month follow-up period from operation. CONCLUSIONS: Prophylactic argon laser retinopexy applied 3-6 weeks before the removal of silicone oil appears to reduce the retinal redetachment rate. A larger prospective randomised trial is needed to confirm these findings. PMID- 9373472 TI - Cone ERG subnormality to red flash in central retinal vein occlusion: a predictor of ocular neovascularisation? AB - In patients with unilateral central retinal vein occlusion (CRVO), we retrospectively examined whether cone electroretinogram (ERG) subnormality to red flash (ratio of the b-wave amplitude in the CRVO eye to that in the normal fellow eye < 1) found at the time of diagnosis of the CRVO was a predictor of later ocular neovascularisation. Ganzfeld ERG cone and rod responses had initially been obtained in a consecutive series of 21 patients with unilateral CRVO. Patients were re-evaluated 6-55 months later to determine whether ocular neovascularisation had developed. Of the 21 CRVO eyes, 6 (29%) were subnormal to red in the affected compared with the normal fellow eye. At follow-up, all 6 (100%) patients had developed ocular neovascularisation compared with 1 (7%) of the 15 patients who were supernormal to red (p = 0.00013). Cone ERG subnormality to red flash in CRVO eyes compared with normal fellow eyes may be a predictor of later development of ocular neovascularisation. PMID- 9373473 TI - Ocular pain: a casualty study. The spectrum and prevalence of pain in acute eye disease. AB - This study examined the prevalence and severity of ocular pain in eye casualty patients. All new patients presenting over a 1 month period were invited to indicate their pain level using a visual analogue scale. The results for 352 patients were analysed, and median pain levels calculated for 29 common diagnoses. Of those responding, 94% (= 47% of all new patients) had ocular pain at presentation. While many results were predictable, some diagnoses were associated with higher pain scores than expected. Junior ophthalmologists also were asked to indicate their perceptions of pain severity for the 29 diagnoses using the same visual analogue scale. PMID- 9373474 TI - Communication and compliance in eye casualty. AB - PURPOSE: This study aimed to assess patients' perceptions and priorities when consulting doctors in eye casualty, to assess their satisfaction with eye casualty and to evaluate and improve patients' level of knowledge and understanding of their treatment. METHODS: A selected consecutive group of 130 patients presenting to eye casualty between 1 July and 15 September 1995 was interviewed by two of the authors prior to collecting their medication. A further group was interviewed again after collecting their medication from the hospital pharmacist. The hospital pharmacist reiterated treatment details when patients collected their medication. Interviews were conducted by means of a questionnaire. There was no inter- or intraobserver variation. Patients' priorities and perceptions were measured as percentages of the group. Patient satisfaction was measured both by a score on a standardised questionnaire and on a visual analogue scale. Patient recall of treatment details was scored as correct or incorrect. The score prior to and after seeing the pharmacist was compared in those patients who were interviewed after collecting their medication. RESULTS: Among the patients 30.8% considered themselves emergencies, 20.8% were referred and the remainder attended for non-urgent reasons. Eighty three per cent (83.0%) were wholly satisfied with the consultation. The consultation scored an average of 8.3, SD 1.6, measured on a visual analogue scale of 0-10. When asked the most important aspects of the consultation 54.6% cited treatment, 25.4% reassurance and 20.0% diagnosis. Ninety-six per cent felt that their treatment had been adequately explained; however, 78.3% made errors when reporting their regimen. A significant improvement in patients' level of recall was found after they had received further information from the hospital pharmacist. CONCLUSIONS: Firstly, this study shows patients' perceptions and priorities when visiting eye casualty. Secondly, it demonstrates that patients are generally satisfied with their eye casualty attendance. Thirdly, many patients depart with poor understanding of their eye treatment regime which is likely to affect compliance. Communication between doctors and patients was enhanced by involvement of the hospital pharmacist. This strategy is applicable not only to an ophthalmic casualty unit but also to a wider range of settings and could provide a service standard for future audit. PMID- 9373475 TI - Management of Mooren's ulceration. AB - Although the diagnosis may be difficult when a patient first presents with Mooren's ulceration, the clinical appearances are characteristic and should not be confused with other conditions which cause corneal ulceration. Based on the clinical presentation and the low-dose anterior segment fluorescein angiographic findings, there seem to be three distinct varieties of Mooren's ulceration: (1) Unilateral Mooren's ulceration (UM), characterised by an excessively painful progressive corneal ulceration in one eye in elderly patients, associated with non-perfusion of the superficial vascular plexus of the anterior segment. (2) Bilateral aggressive Mooren's ulceration (BAM), which occurs in young patients, progresses circumferentially and, only later, centrally in the cornea. Angiography shows vascular leakage and new vessel formation which extends into the base of the ulcer. (3) Bilateral indolent Mooren's ulceration (BIM), which usually occurs in middle-aged patients presenting with progressive peripheral corneal guttering in both eyes, with little inflammatory response. There is no change from the normal vascular architecture on angiography except an extension of new vessels into the ulcer. The management differs in each of these varieties. PMID- 9373476 TI - Changing indications for penetrating keratoplasty in the west of Scotland from 1970 to 1995. AB - In an attempt to predict the trends which might occur in the changing patterns of corneal surgery in the next decade and hence the financial implications, a retrospective study of the treatment of corneal disease was carried out using the pathological reports issued during the last 25 years in the West of Scotland Ophthalmic Pathology Service. This is a supra-regional specialist service which covers the major population areas in Scotland, although most of the specimens were submitted by consultants in the teaching hospitals in Glasgow. The major indications for surgery in the 1486 specimens received were post-inflammatory scarring (387 cases), repeat penetrating keratoplasty (309), keratoconus (257), Fuchs' dystrophy (120) and secondary endothelial failure after cataract surgery (158). In the past 6 years the indications changed and the commonest indications were secondary endothelial failure and post-inflammatory scarring. The study demonstrates a regional difference when compared with other reports and highlights the increasing demand for penetrating keratoplasty and the consequent resource implications. PMID- 9373477 TI - Is there a link between corneal structure and the 'corneal cross'? AB - The 'corneal cross', observed when polarised light is reflected from the cornea and viewed through a crossed analyser, has been attributed to the fine anisotropic structure of the cornea causing birefringence or, alternatively, multiple reflections. But when plane polarised light is similarly reflected from isotropic curved surfaces and viewed through a crossed analyser, isogyres are also seen. Moreover, they vanish with a gonioscopic lens neutralising corneal curvature. This suggests that the corneal cross is not a specific attribute of corneal birefringence. PMID- 9373478 TI - Clinical diagnosis of ocular sarcoidosis. AB - PURPOSE: To assess the value of raised serum angiotensin converting enzyme (ACE) levels in making a clinical diagnosis of ocular sarcoidosis in patients with intraocular inflammation, compatible with sarcoidosis, in whom tissue biopsy is either not practical or not possible. METHODS: The ocular manifestations and clinical course of 22 patients with intraocular inflammation compatible with sarcoidosis and elevated ACE level (including 11 patients with abnormal chest radiograph) were compared with those of a group of 18 patients with intraocular inflammation due to biopsy-proven sarcoidosis. The mean follow-up (+/- SD) was 4.5 +/- 3.4 years in the presumed ocular sarcoidosis group and 7.8 +/- 5.3 years in the biopsy-proven sarcoidosis group. RESULTS: There was no difference in sex, race and age distribution between the two groups. No statistically significant difference could be found between the ocular manifestations seen in each group. The most common finding was retinal vasculitis with panuveitis, seen in 86.4% of the presumed ocular sarcoidosis group and in 83.3% of the biopsy-proven sarcoidosis group. CONCLUSIONS: These results suggest that intraocular inflammation compatible with sarcoidosis in conjunction with raised ACE levels would be accordant with a diagnosis of sarcoidosis in patients in whom histological diagnosis is either not practical or not possible. PMID- 9373479 TI - Short-term effects of topical levobunolol on the human retinal circulation. AB - PURPOSE: The effect of topical levobunolol HCl 0.5% on the retinal circulation was studied on 15 normal volunteers aged 21-54 years (32 +/- 10 years). METHODS: In a double-masked, randomised design, one eye of each subject received a drop of levobunolol HCl 0.5% (LEV) and the fellow eye received a drop of artificial tears (TEAR). Leucocyte velocity (VBFS) and density in the retinal macular microcirculation were measured by the blue-field simulation technique. Venous diameter (D), maximum erythrocyte velocity (Vmax) and volumetric blood flow rate (Q) were measured in a major temporal vein by laser Doppler velocimetry and monochromatic fundus photography. RESULTS: The following average changes from baseline were observed 2 hours after treatment: heart rate, -4.6 +/- 8.3% (p = 0.04); intraocular pressure, -31.7 +/- 10.6% (p = 0.0001); and perfusion pressure, 15.4 +/- 14.4% (p = 0.02) in LEV eyes; no statistically significant changes in IOP and perfusion pressure were seen in TEAR eyes. When each eye was compared with its own baseline, there were no significant changes in VBFS, density, D, Vmax and Q in LEV eyes. In TEAR eyes, there were no significant changes in VBFS, density, Vmax and Q, but a significant change in D (-1.8 +/- 2.6%; p = 0.02) was observed. A significant average percentage increase in Q of 10.9 +/- 19.2% (paired t-test between the change after LEV and the change after TEAR, p = 0.044) was seen in LEV eyes when compared with TEAR eyes. Twelve of the 15 subjects demonstrated a relative increase in Q in the LEV eyes in comparison with the TEAR eyes, while 3 subjects showed the opposite. CONCLUSION: A significant difference in the effect of levobunolol between the two eyes was detected, even though there was no statistically significant effect when each eye was compared with its baseline. PMID- 9373480 TI - Surgical treatment of supranuclear and internuclear ocular motility disorders. AB - Patients with supranuclear and internuclear ocular motility disorders may have nystagmus and oscillopsia, or need to adopt an abnormal head posture to either fixate or maintain binocularity. Many have a cosmetically unsatisfactory appearance. In addition, because of lesions involving ocular motor nuclei or nerve fascicles, double vision is also a common problem. The usual management of these patients is symptomatic with occlusion or prisms. We report on 11 patients who underwent extraocular muscle surgery with the aim of reducing symptoms and restoring or improving binocular single vision. Three patients had bilateral internuclear ophthalmoplegia with exotropia, 3 had dorsal midbrain syndrome, 2 had residual upgaze palsies after cerebral vascular accidents, 2 had oculopalatal myoclonus and one skew deviation. After surgery, symptoms, visual function and cosmesis improved in nearly all patients. We recommend that surgery should be considered more readily in the rehabilitation of these patients. PMID- 9373481 TI - Clear cornea sutureless phacoemulsification and astigmatic decay after two years. AB - PURPOSE: To determine whether clear cornea temporal sutureless sections lead to astigmatic decay over a 2 year period. METHOD: The difference between (a) pre operative keratometric cylinder and keratometric cylinder at final follow-up, and (b) spectacle cylinder at 1 month post-operation and final follow-up, was calculated for 43 eyes. RESULTS: The mean difference in keratometric cylinder between pre-operation and final follow-up was 0.12 D with the rule (WTR) or against the wound. The range was from 0.7 D WTR to 0.4 D against the rule (ATR). Eighty-two per cent of eyes did not change by more than 0.3 D. The mean change in spectacle prescription between 1 month post-operation and final follow-up was 0.05 D ATR, range 0.5 D WTR to 1.0 D ATR. At final follow-up 93% of eyes were seeing 20/40 or better unaided. CONCLUSION: A carefully constructed temporal wound can remain astigmatically neutral. PMID- 9373482 TI - Is hyaluronidase helpful for peribulbar anaesthesia? AB - A prospective, randomised controlled study was performed to investigate whether hyaluronidase improved the efficacy of peribulbar anaesthesia. Ninety-two patients undergoing peribulbar anaesthesia for intraocular surgery all received 10 ml of an anaesthetic solution consisting of a 50:50 mixture of 2% lignocaine with 1 in 200,000 adrenaline and 0.5% bupivacaine. Patients were randomised to a hyaluronidase group which received 150 IU/ml hyaluronidase in this anaesthetic solution (a higher concentration than previous studies) or a control group which received no hyaluronidase. There were 44 patients in the hyaluronidase group and 48 patients in the control group. All anaesthetic injections were administered by an experienced ophthalmologist and no supplementary injections were required in any case. The mean time interval between administration of the block and commencement of surgery was 22 minutes. No statistically significant difference was found between the two groups for pre-operative akinesia (p = 0.16), intraoperative akinesia (p = 0.25), eyelid paralysis (p = 0.72), objective analgesia (p = 0.23) or subjective analgesia (p = 0.60). The majority of patients in both groups achieved excellent akinesia, eyelid paralysis and analgesia. The reasons for these findings in the light of previously conflicting reports on the value of hyaluronidase in peribulbar anaesthesia are discussed. PMID- 9373483 TI - The maintenance of per-operative mydriasis in phacoemulsification with topical diclofenac sodium. AB - PURPOSE: To determine whether the use of topical diclofenac sodium (diclofenac) pre-operatively improves the maintenance of per-operative mydriasis, in conjunction with irrigating solutions containing adrenaline. METHODS: Sixty-four consecutive patients undergoing phacoemulsification were randomised to receive either diclofenac or no diclofenac in conjunction with cyclopentolate 1% and phenylephrine 10% pre-operatively. They subsequently underwent routine phacoemulsification by one consultant surgeon. Irrigating solutions of balanced salt solution contained adrenaline 1:10(6). Pupil diameters were measured pre sclerostomy, post-phacoemulsification, post-irrigation/aspiration and on day 1 post-operatively. These were then compared by Student's t-test. RESULTS: The two groups were statistically similar in age and sex. The mean pre-sclerostomy pupillary diameters were 8.1 mm in both groups. The mean post-phacoemulsification diameters were 7.6 mm in those receiving diclofenac and 7.2 mm in those not (p = 0.03). The mean diameters after infusion/aspiration were 7.7 mm in those receiving diclofenac and 7.1 mm in those not (p = 0.008). The mean pupillary diameters on day 1 were 5.3 mm in those receiving diclofenac and 4.6 mm in those not (p = 0.003). CONCLUSION: Diclofenac improves the maintenance of per-operative mydriasis, in the presence of irrigating solutions containing adrenaline. PMID- 9373484 TI - Surgical management of ophthalmic trauma due to the Palestinian Intifada. AB - PURPOSE: The purpose of the study was to determine the causes, morbidity and visual outcome of 567 Intifada eye injuries which occurred during a 6 year period from December 1987 to December 1993. METHODS: A prospective study was undertaken of Intifada eye injuries from December 1987 to December 1993 which were treated at the St John Ophthalmic Hospital, Jerusalem, or in private clinics in East Jerusalem, the West Bank and Gaza. RESULTS: Seventy-five per cent of those injured came from East Jerusalem or the West Bank. The average age of a person injured was 17 years. Male preponderance was 84.7%. The study demonstrates both the high morbidity and the poor visual outcome which characterise Intifada eye injuries. There were 567 eyes in the series, of which 143 (25.2%) lost perception of light and 72 (12.6%) had vision less than or equal to 6/60. Eighty-six eyes (15.1%) required enucleation. In total 43.1% of the series had severe ocular injuries. Rubber or plastic bullets caused 154 injuries. They were the commonest indication for the enucleation of an eye (90.6% of 86 enucleations). There were 3 cases of severe Gram-negative endophthalmitis in the group of patients who presented late to the hospital (0.52%). CONCLUSIONS: Intifada injuries are associated with far greater morbidity than non-military eye injuries. Rubber or plastic bullet injuries are the leading cause of visual loss and of eye enucleation. Military curfews exacerbate the morbidity of Intifada injuries by prolonging evacuation time. PMID- 9373485 TI - The prognostic value of flash visual evoked potentials in the assessment of non ocular visual impairment in infancy. AB - The results of flash visual evoked potentials (VEPs) in 44 infants blind or severely visually impaired from non-ocular causes are presented, and related to the subsequent visual outcome. Ocular causes of visual impairment were excluded by clinical examination and electroretinography. Using a 2 x 2 contingency table, a significant association between VEP and outcome was demonstrated (chi 2 = 3.51, 1 d.f., p = 0.05). Of 13 infants with normal VEPs, 11 demonstrated substantial visual improvement (negative predictive value = 84.6%). However, of the 31 with abnormal VEPs, only 14 remained severely impaired/blind; the other 17 demonstrating visual improvement (positive predictive value = 45.1%). The sensitivity of the method was high in that 14 of 16 (87.5%) infants who remained impaired/blind had abnormal VEPs, but specificity was low as only 11 of 28 (39.3%) who showed visual improvement had normal VEPs. The accuracy of the technique was therefore low, 25 of 44 (56.8%) being true positive/ negative. With regard to visual outcome when faced with an apparently blind infant, it is important not to be too pessimistic for, as is shown in this study, 28 of 44 demonstrated substantial improvement. There are no absolute indicators of prognosis, but the presence of structural cerebral lesions and a history of either neonatal meningitis or encephalopathy are relatively bad prognostic signs. The flash VEP, despite its limitations, is a useful prognostic tool, particularly in those apparently blind infants whose normal ocular examination/electroretinogram is accompanied by normal VEPs. Those with abnormal VEPs, however, do not necessarily have a poor prognosis, but should be followed up as maturational changes and/or improvements in function of the sensory pathway will be reflected in the evoked potentials. PMID- 9373486 TI - Presentation of retinoblastoma as phthisis bulbi. AB - PURPOSE: We sought to determine the incidence of retinoblastoma patients who presented with phthisis bulbi. METHODS: The medical records of 272 patients in the King Khaled Eye Specialist Hospital Retinoblastoma Registry were retrospectively studied. Clinical records, radiological investigations and histopathological slides were reviewed. RESULTS: We found that 2.7% of patients had retinoblastoma coincident with phthisis bulbi. Five of 10 patients had bilateral retinoblastoma; in the others it was unilateral. Radiologically, intraocular calcification was present in all except one case. All enucleated phthisical globes had residual viable tumour cells; optic nerve extension was found in 2 patients who had long-standing phthisis bulbi. CONCLUSION: Phthisis bulbi is an uncommon presenting sign of retinoblastoma which often occurs after an ocular inflammatory episode possibly related to intraocular tumour infarction. In most cases the tumour is not visible because of intraocular disruption. That every enucleated eye in this series harboured well-differentiated tumour cells underlies the seriousness with which phthisis bulbi of unknown origin in children should be investigated for retinoblastoma. PMID- 9373487 TI - Photorefractive keratectomy in refractive accommodative esotropia. AB - Photorefractive keratectomy (PRK) was performed on a 19-year-old man with hyperopic astigmatism and refractive accommodative esotropia. The patient was orthophoric while wearing spectacles, but had an esotropia of 30 prism dioptres at near and distance vision without spectacles. The best corrected visual acuity of the right eye was 20/50 and of the left eye was 20/20. The excessive accommodative convergence of the patient was eliminated by correcting the hyperopic refractive error by performing PRK, and the patient became orthophoric after the treatment. PMID- 9373488 TI - Visual acuity scored by the letter-by-letter or probit methods has lower retest variability than the line assignment method. AB - PURPOSE: The optimal method for scoring visual acuity measures is unknown. Our goal was to determine, in a clinical setting, the method of scoring visual acuity with the lowest test-retest variability. METHODS: We investigated the effect of three different scoring methods using the Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity chart comparing 32 patients with macular disease and 38 age-matched normal subjects. All subjects completed six repetitions of ETDRS charts. Three scoring methods were then used (line assignment, ETDRS or letter-by letter and probit), the results were converted to log MAR values and the test retest variabilities analysed. RESULTS: We found significant differences in variability among the three scoring methods (p < 0.0001). The variability was greatest with the line assignment method and less with the ETDRS and probit methods. The ETDRS and probit methods had similar variabilities. The difference in variability between normals and patients was not statistically significant. There were no differences in the calculated visual acuities among the three methods, only the variabilities. Using the ETDRS or probit methods, the within test standard deviation was about 0.04 log MAR units (two letters). CONCLUSION: Test-retest variability of visual acuity measurements is lower using the ETDRS or probit methods than the traditional line assignment method. PMID- 9373489 TI - An unusual side effect of Dorzolamide. PMID- 9373490 TI - Adenoma of the non-pigmented epithelium of the ciliary body. PMID- 9373491 TI - Intraocular deposition of metallic fragments during phacoemulsification: possible causes and effects. PMID- 9373492 TI - Local anaesthesia revisited. PMID- 9373493 TI - Local anaesthesia revisited. PMID- 9373494 TI - Local anaesthesia revisited. PMID- 9373495 TI - Ocular perforation during peribulbar anaesthesia. PMID- 9373496 TI - Ocular perforation during peribulbar anaesthesia. PMID- 9373497 TI - Ocular perforations during peribulbar anaesthesia. PMID- 9373498 TI - Ocular perforation during peribulbar anaesthesia. PMID- 9373499 TI - Ocular perforation during peribulbar anaesthesia. PMID- 9373500 TI - CS gas injury to the eye. PMID- 9373501 TI - Warming lignocaine reduces the pain of injection during local anaesthetic eyelid surgery. PMID- 9373502 TI - The efficiency of tropicamide applied topically using a novel ophthalmic delivery system. PMID- 9373503 TI - Phacoemulsification versus endocapsular cataract extraction in a unique cohort of patients. PMID- 9373504 TI - Flashes and floaters as predictors of vitreoretinal pathology. PMID- 9373505 TI - Retinopathy in haemoglobin C trait. PMID- 9373506 TI - Vortex or whorl formation of cultured corneal epithelial cells induced by magnetic fields. PMID- 9373507 TI - An audit of the 1995 Royal College of Ophthalmologists guidelines for screening for retinopathy of prematurity. PMID- 9373508 TI - A randomised trial of topical versus sub-Tenon's local anaesthesia for small incision cataract surgery. PMID- 9373509 TI - A randomised trial of topical versus sub-Tenon's local anaesthesia for small incision cataract surgery. PMID- 9373510 TI - E coli panophthalmitis with orbital cellulitis. PMID- 9373511 TI - Early dehiscence of the conjunctival wound over a hydroxyapatite implant. PMID- 9373512 TI - Do Mersilene sutures need to be removed after cataract surgery? PMID- 9373513 TI - Assessment of intraocular pressure during fractionated peribulbar anaesthesia. PMID- 9373514 TI - The pre-operative assessment and investigation of ophthalmic patients. PMID- 9373515 TI - Food packaging, international standards related to food safety and quality, and trade. AB - International trade is subject to the Final Act of the Uruguay Round Multilateral Trade Negotiations' Agreement on the Application of Sanitary and Phytosanitary Measures (the SPS Agreement) and Agreement on Technical Barriers to Trade (the TBT Agreement). These Agreements, the purpose of which is the freeing up of trade and the removal of restraints to the greatest extent possible, affect all countries that are members of the World Trade Organization, and have an impact upon all countries that are exporters. Trade in food is subject to these rules, which include provision for countries to apply safety and quality measures to protect the consumer. Such consumer protection measures extend to all aspects of food, including its packaging. The SPS and TBT Agreements press for 'harmonization' based upon the adoption of standards developed by international standards setting bodies and require countries to participate in their work. The relevant body with respect to food safety and quality measures is the Codex Alimentarius Commission, which is implemented by the Joint FAO/WHO Food Standards Programme. The work of the Codex Alimentarius Commission in harmonization within the context of food packaging and the rules applying to world trade is discussed. PMID- 9373516 TI - Overview of the Hungarian packaging industry. AB - A brief overview of the structure of the Hungarian packaging market is presented as well as recent trends in packaging development. The activities of several industrial organizations in the Hungarian packaging material industry (CSAOSZ/HAPEC) are reviewed, together with their suggestions for responsible solutions to the packaging waste problem. The eventual agreement regarding the handling of packaging waste between the industrial associations and the Ministry for Environmental Protection is outlined. PMID- 9373517 TI - Overview of food packaging research in Hungary. AB - In the last 15 years, increasing demands for improvement in food quality, and for increased food choice have grown in Hungary. To meet these new requirements, packaging is of decisive importance. Considerable developments have been achieved as a result of wide-ranging R&D activities. A review compiled by the author is presented of the actual situation regarding Hungarian food packaging, covering the main domestic institutions for R&D activities dealing with packaging materials and methods, together with a discussion of trends and results. PMID- 9373518 TI - Methods and approaches used by FDA to evaluate the safety of food packaging materials. AB - In the Federal Register of July 17 1995 (60 FR 36582), the US Food and Drug Administration (FDA) established a 'threshold of regulation' process. This process was established for determining when the extent of migration to food is so trivial that safety concerns would be negligible. The process exempts materials in food-contact articles whose use results in dietary concentrations at or below 0.5 ppb (microgram/kg) from the food additive listing regulation requirement. Carcinogens or substances that may be carcinogens are excluded from this regulation. This paper explores some of the ramifications of the threshold of regulation policy with respect to traditional migration testing. It examines the use of the threshold approach and migration modelling to estimate food additive exposures. These results indicate that modelling may be a reasonable alternative to traditional migration testing. PMID- 9373519 TI - Enforcement of food packaging legislation. AB - A survey of the results of the analysis of samples of packaging materials, obtained from the Dutch market during the last 5 years is presented. The diethylether extracts of food contact polymers were analysed by GC-MS according to the Dutch testing system. Lists of the identified constituents in the extracts of polystyrene (PS), polypropylene (PP), polyethylene (PE), polyethylene terephthlate (PET) and polyvinylchloride (PVC) are given. More than 50 constituents were identified in the more than 1000 samples investigated. An estimation of the quantities of the extracted constituents has been made. In PVC the following compounds were present in relatively large quantities (10 times the height of the internal standards): diethylhexyladipate, dinonylphthalate, and other phthalates. However 68% of the extracts contained no peaks higher than the internal standards. PMID- 9373520 TI - Activities and current research from the EC, standards, measurements and testing programme (SMT) in the area of food contact materials. AB - The EC, Standards, Measurements and Testing Programme (SMT) is the successor of the Measurements and Testing Programme (M&T) and the Community Bureau of Reference (BCR). Its objectives include the provision of research and technical support to standardization and health of the society when it is required to improve the competitive position of European industry, and for the development or implementation of Community policy. The SMT-Programme is currently supporting a number of different types of collaborative projects in the food packaging sphere. Their objectives range from method development via preparation and certification of reference materials, preparation of a handbook and the update of a spectral atlas to pre-normative research providing information on a number of sources and wide range of packed products being transported throughout Europe. PMID- 9373521 TI - Quick methods to control compliance of plastic materials with food packaging regulations. AB - A general strategy is presented, aiming to provide plastics manufacturers, food industries and enforcement laboratories with quick methods to check whether migration from materials for food contact will be acceptable during the time of use. The strategy involves several steps, with increasing time demand and cost. Monitoring extraction kinetics allows both the optimization of the extraction time, and the selection of conditions where extraction is more severe than migration. The influence of the extracting solvent is discussed. It may give rise to specific non-extraction of some migrants, which may change the conclusions when the solvent is used in replacement of a fatty food simulant. Factors ruling this effect at a given temperature are identified: the affinity to the solvent with the migrant (selectivity), its ability to reach molecules entangled in the polymeric network (accessibility) and its interaction with the polymer (penetration). The kinetic parameters of the penetration of olive oil into polypropylene have been determined by the determination of profiles of concentration. PMID- 9373523 TI - An ultraviolet spectrophotometric method as an alternative test for determining overall migration from aromatic polyester packaging materials into fatty food oils. AB - The generic test method developed by the European Committee for Standardization (CEN) Sub Committee 1 (SC1), CEN ENV 1186, for determining overall migration from plastics into fat simulants is complex, time consuming and the test precision is poor. An ultraviolet (UV) spectrophotometric test method that utilizes the first derivative of absorbance (d[A]/d[lambda]) has been developed for determining overall migration into oil from polyethylene terephthalate (PET) and other aromatic polyester packaging materials which correlates with overall migration values obtained by the CEN method. The UV method can be used as a control method instead of the CEN method for overall migration testing in most instances and may require only about 10% of the time needed to conduct the CEN test. For modified polyester packaging materials such as foamed articles, the UV test method is a better test for overall migration. In addition to the overall migration information, the UV data also indicate if additional testing for the specific migration of terephthalic acid (TPA) into the fat simulant is required. HB 307 oil is the preferred fatty food simulant but olive oil can also be used. PMID- 9373522 TI - Magnetic resonance imaging studies of diffusion in polymers. AB - For a number of polymer/penetrant systems, for example fatty foods in direct contact with plastic wrapping, the migration of substances from the polymer is governed by the amount of penetrant entering the polymer. For food packaging this means that the rate of migration of substances into the food can be governed by the uptake of food into the packaging itself. To develop predictive models of migration under various conditions there is therefore a need to understand the mechanism of the penetration of the food into the packaging. In this paper a summary of recent Magnetic Resonance Imaging (MRI) studies is reported. Uptake of simulant, as measured by MRI, is quantitative and agrees well with gravimetric uptake data. Data are shown for a comparison of olive oil and isooctane penetration into low density polyethylene at various temperatures. Further, the rate of ingress of isooctane into a variety of commercial polyethylene plaques has been shown to differ widely. These data also allow us to probe the molecular interactions between polymer and penetrant. Finally MRI is combined with a Pulsed Gradient Spin Echo (PGSE) technique to provide spatially resolved measurements of penetrant diffusivity within a polymer. Diffusivity as a function of volume fraction of penetrant can also be measured. These data provide invaluable insights into diffusion in polymers which will aid development of more accurate models of polymer/penetrant interactions and small molecule mobility. PMID- 9373524 TI - Food-packaging interactions influencing quality and safety. AB - Interactions between foods and packaging can be detrimental to quality and/or safety. Changes in product flavour due to aroma sorption and the transfer of undesirable flavours from packaging to foods are important mechanisms of deterioration when foods are packaged in polymer-based materials. Careful consideration must be given to those factors affecting such interactions when selecting packaging materials in order to maximize product quality, safety, and shelf-life while minimizing undesirable changes. Product considerations include sensitivity to flavour and related deteriorations, colour changes, vitamin loss, microbial activity, and amount of flavour available. Storage considerations include temperature, time, and processing method. Polymer considerations include type of polymer and processing method, volume or mass of polymer to product ratio, and whether the interaction is Fickian or non-Fickian. Methodology to determine the extent of such interactions must be developed. Direct interactions between food and packaging are not necessarily detrimental. The same principles governing undesirable interactions can be used to affect desirable outcomes. Examples include films which directly intercept or absorb oxygen, inhibit microorganisms, remove undesirable flavours by sorption, or indicate safety and product shelf-life. PMID- 9373525 TI - Study of aroma scalping through thermosealable polymers used in food packaging by inverse gas chromatography. AB - Scalping of aroma components in polymers used for food packaging was determined by solubility experiments. Aromas were selected from different families: esters, alcohols, hydrocarbons and ketones. Polymers were a linear low density polyethylene (LLDPE), an ionomer and a new thermosealable polyester (PET). Polymers were selected from thermosealable materials because of their resistance to fats and oils. Sorption isotherms (low sorbate activity range) for every system aroma (vapour)/polymer were determined by inverse gas chromatography. Isotherms were found to be linear. Hence, solubility coefficients (S) as defined by Henry's law were calculated from the isotherm slopes. According to S values, PET appears to be the best choice to minimize aroma scalping by sorption in the packaging inner layer, Ionomers improve the barrier to aroma when compared with LLDPE except for polar sorbates. Sorption of aroma components was shown to be selective, e.g. limonene was preferentially sorbed in LLDPE. The value of S for the limonene/LLDPE system was 2.5 times the value of S for ethyl caproate/LLDPE. This selectivity may lead to an imbalance in the flavour and may be more important than the prevention of overall scalping. PMID- 9373526 TI - Rapid assessment of food/package interactions by electrochemical impedance spectroscopy (EIS). AB - Food components migrating through organic layers are able to influence the adhesive properties of multilayer materials. In the case of coated metal substrates the interaction stability may be reduced by delamination and subsequent corrosion processes during storage. Impedance spectroscopy can be used to give a very early indication of a reduced interaction stability of a packaging material by measuring the delamination tendency. Applications are presented for laminated aluminium foil material. The delamination is induced by a cathodic treatment of samples prepared from the package. A comparison is made of material with no contact and with only a few days contact with the filled product. Main applications are foreseen as the replacement of long-term storage tests to establish the compatibility of food and package material and to work out the specific influence of individual food components. PMID- 9373527 TI - Presentation and experimental verification of a physico-mathematical model describing the migration across functional barrier layers into foodstuffs. AB - For several years there has been an ongoing controversial scientific discussion about the so-called functional barrier concept which, although mostly connected with the re-use of recycled plastics for food packaging, has general relevance and is principally applicable to any type of multilayer structure. Concerning the definition of the efficiency of a functional barrier there exists different understandings, ranging from the absolute physical barrier requirement over the acceptance of toxicologically insignificant migration to a completely lag time related definition. The starting point of this work was the fact that functional barriers are in most cases already in-situ-contaminated due to the thermally extreme coextrusion conditions of the manufacturing process. As a consequence, middle layer contaminants may already have penetrated the functional barrier of a food package and may provide direct contact with the foodstuff at the time when the package is filled. Nevertheless, depending on the individual food package parameters, the remaining functional barrier efficiency can still prevent inadmissible migration. To meet this real-life situation and to describe the underlying migration process a theoretical migration model was developed and experimentally verified in this work using artificially-contaminated multilayer HIPS sheets with different functional barrier thicknesses. An important result of this study was the finding that compared with the interdiffusion between the package's layers in situ during their formation in the coextrusion process, the interdiffusion at ambient temperature until the filling time point of the package is able to be neglected. PMID- 9373528 TI - Modelling transport between a monolayer and a bi-layer polymeric package and food. AB - There is considerable interest in the recycling of food packaging, but also the potential for problems. Any chemical component initially located in the re-used food packaging may be responsible for contamination of the food. The kinetics of this transfer can be established whether the food is liquid or solid. The process is controlled by diffusion in the packaging and by convection in the liquid food or by diffusion in the solid food. A bi-layer package made of a re-used polymer layer and a virgin polymer layer exhibits quite different kinetics for the contamination of the food. The role of the virgin polymer layer or so-called functional barrier can be established either by the kinetics of contaminant transfer or by the profiles of concentration developed through the packaging-food system. Dimensionless numbers are used in order to be of help to anyone in need of precise information on the length of time this functional barrier offers protection of the food. PMID- 9373529 TI - Prospects for application of post-consumer used plastics in food packaging. AB - The two most widely used polymers in packaging in recent years are polyethylene terephthalate (PET) and polyethylene (PE). The biggest fractions of these polymers are not re-utilized, in spite of the fact that they possess excellent properties even after their first application. The ban on using recycled polymers in food packaging applications and the lack of good value outlets for these materials causes them to end up in landfills. The high cost nylon, used in packaging primarily as high gas barrier laminates with PE, also finds its way to landfills. In this case, the reason is the difficulty of recycling different polymers that are incompatible. Thus, the Municipal Solid Waste (MSW) stream transferred to landfills contains many plastic packages. These packages are being blamed as a major pollutant of the environment in spite of the fact that all plastics contribute only a small percentage to the weight of the garbage in landfills. If proper and cost effective applications for the recycled polymers could be developed, the waste related to their disposal could be limited. In addition, the contribution of plastic packages to the environmental problem could be diminished. In the present paper, the possibility of sandwiching a contaminated PET layer between two layers of the virgin material was studied. The aim of the study was to determine whether such an operation could lower the migration level of contaminants from a multilayer structure (containing a recycled layer of PET) to values below the limits required by regulatory agencies. The diffusion coefficients (required to determine migration) of four organic liquids in PET were determined. As a result of the sandwiching operation, the amount of pollutant (toluene) migrating into the food simulant was reduced by two orders of magnitude. The properties of PE/nylon blends were also studied. It was found that the high gas barrier properties of nylon are preserved in the blend when proper processing conditions are used. Therefore, the recycled material could be used as a centre layer in a multilayer structure providing good gas barrier properties to this structure. PMID- 9373530 TI - The threshold of regulation and its application to indirect food additive contaminants in recycled plastics. AB - Recycled plastics have been used in food-contact applications since 1990 in various countries around the world. To date, there have been no reported issues concerning health or off-taste resulting from the use of recycled plastics in food-contact applications. This is due to the fact that the criteria that have been established regarding safety and processing are based on extremely high standards that render the finished recycled material equivalent in virtually all aspects to virgin polymers. The basis for this conclusion is detailed in this document. PMID- 9373531 TI - Evaluation, modelling and optimization of the cleaning process of contaminated plastic food refillables. AB - In this study several types of bottle materials (glass, PET (polyethylene terephthalate), PC (polycarbonate), HDPE (high density polyethylene), PP (polypropylene) and PVC (polyvinyl chloride)) were evaluated in order to be used as food refillables, comparing the residual chemical contamination after classical caustic washing. Bottles were contaminated with model chemicals (chloroxylenol and d-limonene) and caustic washed with varied process parameters using a simulated laboratory-scale washing procedure. After washing, the chemical contaminated bottles were filled with water and stored for 28 days at 37 degrees C. The concentrations of the model chemicals in the water after storage were taken as a measure of chemical contamination. The influence of the cleaning parameters (temperature, caustic and commercial additive concentration) was studied using response surface methodology. Washing temperature showed a significant influence on the removal of absorbed chemicals from surfaces compared with the effect of the caustic and especially the additive concentration. Optimization of caustic cleaning for the cleaning process in question led to better cleaning effectiveness, although none of the different washing conditions were able to remove all absorbed chemicals out of the polymeric resins. Commercially available plastic refillables (PET and PC) showed the best chemical rinsability. Glass bottles, however, had in every case the best rinsing characteristics. PMID- 9373532 TI - Validation studies of a quick test for predicting the sorption and washing properties of refillable plastic bottles. AB - Quick tests are proposed in the literature as alternatives to the large scale contamination and washing studies performed to date to assess the acceptability of plastic beverage bottles for refilling. These tests use small plastic specimens ('strips') in place of bottles and use mixtures of surrogate contaminants to model the myriad of chemicals that could in principle contaminate returned bottles because of consumer mis-use. The work reported here has measured the sorption and wash performance using the quick test protocol with PET (polyethyleneterephthalate) strips and laboratory washing and compared the results with tests using actual bottles and a commercial washing process. The comparison indicates that the quick test satisfactorily simulated contamination and commercial washing of intact bottles. The results also show that repeated washing of PET bottles does not cause higher sorption of contaminants. PMID- 9373533 TI - Purity of recycled fibre-based materials. AB - In order to study the purity of recycled fibre-based materials, products containing recycled fibre as well as recycled pulp were examined with regard to their chemical impurities, toxicity and microbiological quality. The study was carried out to clarify both qualitatively and quantitatively the variations in microbiological quality. The levels of several classes of chemical substances were analysed and semi-volatile and volatile substances identified. The toxicity and mutagenicity of virgin fibre and recycled fibre materials were screened using the Photobacter toxicity test and the Ames Salmonella mutagenicity test. Preliminary chemical characterization of the mutagens was carried out. Identification of the compounds found in the mutagenic fractions was performed by gas chromatography/mass spectrometry (GC/MS). The concentration of various substances analysed was found to be low, although the variety of substances present appeared to be very broad. Preliminary chemical characterization revealed that some samples contained compounds known to have mutagenic or other toxic activity. Also, the recycled fibre pulps contained large amounts of various microbes, the microbial load consisting mainly of aerobic spore-forming bacteria. The paper-making process was found to clearly have reduced the total microbial counts. PMID- 9373534 TI - Correlation of specific migration (Cf) of plastics additives with their initial concentration in the polymer (Cp). AB - The first list of plastics additives which may be assigned restrictions in a future amendment to Directive 90/128/ EEC is likely to contain over 200 substances. If food consumption factors are taken into account many compounds on this list could have restrictions removed but there would, without doubt, still be many additives with restrictions. Extensive migration testing of food contact plastics containing restricted additives to ensure compliance would be required. These limits would be difficult to enforce, add significant cost burdens on the packaging industry and, for these reasons, may not provide improved consumer safeguards. An alternative means of control has been proposed based upon polymer composition. However, in order to support such a scheme a reliable correlation between migration of additives to their composition in the polymer must be demonstrated. There has been strong interest in establishing this relationship and a feasibility project to investigate the specific migration of four commonly used additives has been successfully completed. The study was initially funded for 1 year, by the Ministry of Agriculture, Fisheries and Food (MAFF) and industry. Analytical methods to determine the additives in food simulants have been developed and linear correlations have been demonstrated between the concentration of all four additives and their specific migration levels for each polymer studied. Experimental migration data have been compared with those generated by mathematical models. PMID- 9373535 TI - HACCP approach to ensure the safety and quality of food packaging. AB - EC Directive 93/43/EEC of 14 June 1993 on the hygiene of foodstuffs has been implemented in the Netherlands through the Food and Commodity Act (Warenwet) of 14 December 1995. This Directive requires food companies to identify steps in their activities that are critical to ensuring food safety, and to ensure that adequate safety procedures are identified, implemented, maintained and reviewed based on the principles of the Hazard Analysis Critical Control Point (HACCP) system. HACCP is a tool used to assess hazards, estimate risks and establish specific control measures that emphasize prevention and control rather than reliance on end-product testing. Increasing public awareness of food safety, together with the introduction of this new legislation, has led producers and retailers of food to demand higher standards from their suppliers. Suppliers of raw materials, ingredients and also food packaging will be expected to bring their standards of hygiene in line with the expectations of the food industry. Food producers will need to obtain the guarantee from their suppliers that the packaging does not negatively influence their products. HACCP is a method that can also be applied to ensure the safety and other quality aspects of all kinds of food packaging materials such as films, foils, trays, cups, boxes and tubs made of paper, cardboard, polymers, metal and other materials (single use or disposable packagings as well as re-usable and recycled packagings). At the Netherlands Organization for Applied Scientific Research (TNO), the quality and safety aspects of re-use of food packaging, and refillable bottles in particular, have been the subject of extensive investigations in the project 'Quality monitoring of synthetic refillable bottles'. In this paper the set-up of the project and the Codes of Practice for refillable bottles are described. Moreover, the applicability of HACCP to food packagings and an example of a HACCP study for refillable PET bottles will be discussed. PMID- 9373536 TI - Investigations into the potential degradation of polycarbonate baby bottles during sterilization with consequent release of bisphenol A. AB - Twenty-four brands of plastic baby feeding bottles were purchased and all were found to be made of polycarbonate. Taking a batch of one representative sample, the polymer was tested for stability and possible release of bisphenol A following domestic practice of sterilization. Sterilization was by alkaline hypochlorite, steam, or washing in an automatic dishwasher at 65 degrees C with detergent. A total of 20 cycles of sterilization and subsequent food use were performed for each of the three procedures. Bisphenol A migration was in all cases not detectable in infant feed using a very sensitive method of liquid chromatography with fluorescence detection with a 0.03 mg/kg detection limit. PMID- 9373537 TI - Recent innovations in edible and/or biodegradable packaging materials. AB - Certain newly discovered characteristics of natural biopolymers should make them a choice material to be used for different types of wrappings and films. Edible and/or biodegradable packagings produced from agricultural origin macromolecules provide a supplementary and sometimes essential means to control physiological, microbiological, and physicochemical changes in food products. This is accomplished (i) by controlling mass transfers between food product and ambient atmosphere or between components in heterogeneous food product, and (iii) by modifying and controlling food surface conditions (pH, level of specific functional agents, slow release of flavour compounds), it should be stressed that the material characteristics (polysaccharide, protein, or lipid, plasticized or not, chemically modified or not, used alone or in combination) and the fabrication procedures (casting of a film-forming solution, thermoforming) must be adapted to each specific food product and usage condition (relative humidity, temperature). Some potential uses of these materials (e.g. wrapping of various fabricated foods; protection of fruits and vegetables by control of maturation; protection of meat and fish; control of internal moisture transfer in pizzas), which are hinged on film properties (e.g. organoleptic, mechanical, gas and solute barrier) are described with examples. PMID- 9373538 TI - Active and smart packaging for meeting consumer demands for quality and safety. AB - Over the past few decades, many new packaging techniques have been introduced in the quest for natural preservation of foods and on-time quality monitoring of packaged food to ensure good product quality and safety for the consumer. This paper discusses scientific, technological, commercial and legislative development, as well as consumer aspects and acceptance of the active and smart food packaging techniques with current or potential commercial value, and the elements that both the manufacturers of these packaging systems and the food industry should take into account before launching products using these techniques. PMID- 9373539 TI - Minimizing the residual oxygen in modified atmosphere packaging of bakery products. AB - The total elimination of air represents a serious hurdle in modified atmosphere packaging of bakery products, due both to the high spin-rates of the packaging lines and, particularly, to the typical texture of bakery products which retain large quantities of air inside their porous structure. Simulating the gas flushing modified atmosphere packaging with laboratory equipment and measuring the oxygen concentration directly inside bread rolls, by means of a gas analyser connected with the internal portion, it was possible to follow the rate of atmosphere substitution, evaluating the effects of different baking treatments (7, 12 and 23 min at 230 degrees C) and the role played by different gases (nitrogen, argon, helium, nitrous oxide and carbon dioxide). The oxygen content inside the products, plotted versus time, led to typical logistic 'dose-response' curves which made it possible to forecast the time needed to reach established values of residual oxygen concentration and to emphasize the effects of the different conditions used. The gas properties particularly affected the rate of oxygen substitution and the less water-soluble was the gas, the faster was the oxygen reduction; the larger was the gas molecule, the slower was the process. Also baking time was shown to have, to a different extent, some measurable effects on the rate of oxygen substitution and hence, its optimization as well as the choice of gas mixture can contribute to improve modified atmosphere packaging of bakery products. PMID- 9373540 TI - The suitability of alternative fatty food simulants for overall migration testing under both low- and high-temperature test conditions. AB - The suitability of various alternative, volatile fatty food simulants for overall migration testing was investigated under both low- and high-temperature test conditions. The overall migration into olive oil from a large number of commercially used food packaging materials applying various low- and high temperature test conditions (e.g. 2 h at 175 degrees C, 30 min at 130 degrees C, 1 h at 100 degrees C followed by 10 days at 40 degrees C, 10 days at 20 degrees C) was determined. The results were compared with overall migration from these samples into iso-octane, 50% or 95% ethanol and isopropanol under appropriate test conditions. The samples investigated include homogeneous plastic films, laminates, coated board samples, a coated can, and articles. The results of the study indicate that iso-octane, 95% ethanol and isopropanol are suitable alternative fatty food simulants for overall migration testing under various time and temperature conditions. PMID- 9373541 TI - Arytenoid granuloma. PMID- 9373542 TI - Prevalence of otitis media with effusion in multicultural schools in Hong Kong. AB - The prevalence of otitis media with effusion (OME) in Asia has only been studied in a limited fashion. This preliminary study forms part of a larger study aiming to establish the prevalence of OME in Hong Kong. One hundred and seventy-seven children (from multicultural schools) between the ages of five and 6.03 years were screened for OME otoscopy and tympanometry. Nine positive screens (5.1 per cent) were obtained for OME. Within this mixed ethnic group, Chinese children had a significantly lower point prevalence (1.3 per cent) than Caucasian children (9.5 per cent) (p < 0.05). Although the point prevalence from this mixed ethnic group of children was significantly higher (p < 0.05) than that of local Chinese school children (1.95 per cent) by the same group of investigators, the point prevalence in the ethnic Chinese children was comparable. The reason for the lower prevalence of OME in the Chinese population needs further research. PMID- 9373543 TI - Autograft ossicle selection in cholesteatomatous ear disease: histopathological considerations. AB - In order to determine whether selection of autograft ossicles in cholesteatomatous ear disease should be based upon their appearance under the surgical operating microscope, we studied the histopathological features of 113 such ossicles. We attempted to correlate the extent of erosion of the ossicle, as noted under the surgical operating microscope, with their histopathological appearance. There were 60 mallei and 53 includes. Seventy-nine ossicles were eroded and 34 were intact. The commonest abnormality noted was erosion of the long process of the incus (75 per cent). Both intact and eroded ossicles had similar histological features. There was no evidence of intra-ossicular cholesteatoma. The results suggest that the extent of erosion of these ossicles as seen under the surgical operating microscope should in no way prejudice their use as autografts when required. PMID- 9373544 TI - A consideration of the effect of ear canal resonance and hearing loss upon white noise generators for tinnitus retraining therapy. AB - Tinnitus retraining therapy has been heralded as a major advance in the alleviation of tinnitus perception. A cornerstone of this technique is to use white noise produced by a white noise generator (WNG) over a period of several months in order to assist the patient to habituate to their tinnitus. There are three factors which influence the frequency spectrum of the perceived noise such that the perception of white noise from a WNG is unlikely. These factors are the actual spectrum of the emitted noise, the ear canal resonance of the patient and the hearing sensitivity of the patient. Advocates of tinnitus retraining therapy state that white noise is the optimal stimulation to assist habituation of tinnitus. This paper demonstrates that this optimal situation is unlikely to be achieved and that this may account for the long periods needed for patients to achieve benefit from the technique. The development of devices that allow for the above factors to be countered is suggested. PMID- 9373545 TI - A study of mercuric oxide and zinc-air battery life in hearing aids. AB - The requirement to phase out mercuric oxide (mercury) batteries on environmental grounds has led to the widespread introduction of zinc-air technology. The possibility arises that high drain hearing aids may not be adequately catered for by zinc-air cells, leading to poor performance. This study investigated the hearing aid user's ability to perceive differences between zinc-air and mercury cells in normal everyday usage. The data was collected for 100 experienced hearing aid users in field trials. Users report 50 per cent greater life for zinc air cells in high power aids and 28 per cent in low power aids. The average life of the zinc-air cells range from 15 days in high power to 34 days in low power aids. Users are able to perceive a difference in sound quality in favour of zinc air cells for low and medium power aids. The hearing aid population is not disadvantaged by phasing out mercury cells. PMID- 9373546 TI - Teeth in the maxillary sinus--imaging and management. AB - PURPOSE: To evaluate the images obtained by CT in diagnosis and treatment plan of teeth in the maxillary sinus. METHODS: Twelve patients with teeth in the maxillary sinus were studied by plain film radiography (PFR) and by CT with a dental software programme, which displays multiple panoramic and cross-sectional views of the mandible and maxilla. The three-dimensional morphology of the tooth, its inclination, proximity to the sinus wall, surgical planning and prediction of prognosis and complications were estimated on both PFR and on CT scans and scored. RESULTS: The radiographical features interpreted from PFR were fair or poorly diagnosed whereas CT provided excellent features. The surgical approach of choice was based on CT interpretation. CONCLUSION: CT is useful for diagnosis and treatment planning of teeth in the maxillary antrum. PMID- 9373547 TI - Diagnostic importance of the nucleolar organizer regions in Wegener's granulomatosis. AB - The number and distribution pattern of silver staining nucleolar organizer regions (AgNORs) were thought to reflect the cellular proliferative activity and the malignancy of tumours. Using a silver-staining method, the variations of AgNORs have been studied in patients with atypical inflammatory lesion (n = 5), malignant reticulosis (n = 5) and Wegener's granulomatosis (n = 6). Our results reveal that there was a statistically significant difference (p < 0.01), highly suggestive of a difference in AgNOR counts between the atypical inflammatory lesion and Wegener's granulomatosis, with the Wegener's granulomatosis specimens having the higher irregular AgNORs, but the difference between Wegener's granulomatosis and malignant reticulosis is probably not clinically important. It is concluded that AgNORs may be useful in differentiating Wegener's granulomatosis from an atypical inflammatory lesion, and the simplified counting technique is adequate for the purpose. PMID- 9373548 TI - Adult obstructive sleep apnoea syndrome and tonsillectomy. AB - A surgical cure for adult obstructive sleep apnoea syndrome (OSAS) is an attractive alternative to nasal continuous positive airway pressure, but current research suggests that uvulopalatopharyngoplasty is not effective in all patients. No subgroup of these patients, who might benefit from surgery to the oropharynx, has as yet been identified. In this study we examined the results of tonsillectomy either as an isolated procedure or as part of uvulopalatopharyngoplasty in seven patients, who had tonsillomegaly. In all seven there was a short-term improvement between the pre-operative and post-operative apnoea/hypoapnoea (A/H) index (100-65 per cent), which could not be accounted for by change in the body mass index (BMI). In one patient a diagnosis of Non Hodgkin's lymphoma was made from histological examination of the tonsils. The results suggest that adult patients with tonsillomegaly may represent a subgroup of patients with OSAS, who would benefit from surgery aimed at the oropharynx. PMID- 9373549 TI - Horizontal glottectomy: functional and oncological results. AB - The authors report on their experience with 25 cases of horizontal glottectomy and discuss the functional and oncological results of this operation. Indications for this procedure are T1a and T1b glottic carcinomas. The overall three-year and five-year survival was respectively 94 and 88 per cent. Distant metastasis appears to be the major long-term failure, three patients dying of lung carcinoma. Short functional rehabilitation was observed in all cases. Decannulation was achieved in 100 per cent of the cases and none of our patients had laryngeal stenosis. The average time of removal of the nasogastric tube was 11.8 days. Because of its high local control and reduced functional after effects, horizontal glottectomy appears to be a reliable and safe procedure for limited glottic carcinomas and must be included in their therapeutic management. PMID- 9373550 TI - Frey's syndrome: treatment with botulinum toxin. AB - Frey's syndrome, i.e. gustatory sweating on the cheek, is a fairly common embarrassment after parotid gland surgery. New surgical techniques have been proposed to avoid this complication, but are not widely in use. Hence, there is need for treatment of Frey's syndrome. All surgical and topical treatments have drawbacks. This study was set up in order to evaluate a recently described treatment. One hundred and two patients were interviewed after parotidectomy. Thirty-one of them had noticed gustatory sweating and 15 patients underwent Minor's starch iodine test before, and after, treatment with intracutaneous injections of botulinum toxin A (Botox, Allergan Inc., USA). Thirteen of the patients did not experience any gustatory sweating at follow-up (one to 13 months). Minor's starch test showed total disappearance of gustatory sweating in 12 of the 15 treated patients. The only side effect was a discreet, transitory affection of the orbicularis oris muscle in one patient. As this treatment is minimally invasive it could be an attractive treatment for Frey's syndrome if the effect is maintained. Complaints of local hypoaesthesia and pain were also common after parotid surgery. PMID- 9373551 TI - Prophylaxis for venous thromboembolism in head and neck surgery: the practice of otolaryngologists. AB - Deep venous thrombosis (DVT) and pulmonary embolism (PE) are an important cause of morbidity and mortality in the surgical patient. The first guideline produced by the Scottish Intercollegiate Guidelines Network was for the prophylaxis of venous thromboembolism. Patients undergoing major head and neck cancer surgery commonly exhibit risk factors for venous thromboembolism. Currently, however, there are no data on its incidence in these patients. A questionnaire survey was performed to assess the current practice of consultant otolaryngologists regarding DVT prophylaxis in patients undergoing head and neck cancer surgery. Of those respondents who managed these patients, 57 per cent did not use routine DVT prophylaxis while 43 per cent did. A wide variety of techniques were employed among those practising DVT prophylaxis. A consensus is needed concerning the use of thromboembolism prophylaxis in head and neck surgery patients. PMID- 9373552 TI - T cell lymphoma of the ear presenting as mastoiditis. AB - Mastoiditis is a complication of otitis media characterized by suppuration and destruction of air cell septa in the mastoid and petrous pyramid. Diagnosis is made by clinical findings and computerized tomography (CT) of the temporal bone. We present a patient initially diagnosed by CT as having chronic mastoiditis who was subsequently shown to have an unusual large-cell malignant lymphoma of T cell type. PMID- 9373553 TI - 'Farmer's ear': sudden sensorineural hearing loss due to Chlamydia psittaci infection. AB - A case of sudden sensorineural hearing loss in association with a Chlamydia psittaci pneumonia is reported. Rapid recovery was seen when the patient was treated with high dose steroids and appropriate antibiotics. This is the first such case report in the literature. PMID- 9373554 TI - Cavernous haemangioma of the facial nerve. AB - Facial nerve haemangiomas are probably the most frequent benign tumours involving the facial nerve in its intratemporal portion. Usually facial nerve dysfunction is present when these tumours are of extremely small size, the average tumour being less than 10 mm. We present a case of a 15 mm diameter cavernous haemangioma of the geniculate region, with histological findings of nerve infiltration, without facial nerve symptoms. The atypical clinical presentation justifies the report and subsequent literature review. PMID- 9373555 TI - Chondroid syringoma of the nose: report of a case. AB - Chondroid syringoma or mixed tumour of the skin is a rare benign tumour which can present on the face. We present here the case of a patient who underwent an excisional biopsy of a small painless nodule in the soft triangle of the nose for cosmetic reasons. The clinical presentation, histology and treatment, with review of the relevant literature, is discussed. PMID- 9373556 TI - Osteoblastoma of the nasal cavity arising from the perpendicular plate of the ethmoid bone. AB - The presence of a benign osteoblastoma in the ethmoid sinus is rare and only a few cases have been reported. This is a case of a benign osteoblastoma arising from the perpendicular plate of the ethmoid bone with extension to the nasal cavity. The diagnosis and management of this unusual lesion, as well as the histopathology and the imaging characteristics are reviewed. We also review the previously reported cases of benign osteoblastomas of different origin, with nasal cavity involvement. PMID- 9373557 TI - Ortner's syndrome: a centenary review of unilateral recurrent laryngeal nerve palsy secondary to cardiothoracic disease. AB - Ortner's Syndrome (described 100 years ago in 1897) is a clinical entity with hoarseness due to a left recurrent laryngeal nerve (LRLN) palsy caused by cardiac disease. A 35-year-old woman presented with a LRLN palsy due to a huge thoracic aneurysm. The anatomy of the LRLN and the cardiothoracic complaints which may cause the palsy are discussed. PMID- 9373558 TI - Tuberculoma of the cheek: a case report. AB - Tuberculoma of the cheek in the absence of tuberculosis elsewhere in the body is rarely seen and hence rarely thought of as a differential diagnosis when such a patient presents. In the following case, the patient was provisionally diagnosed as carcinoma of the cheek because of the exophytic nature of the growth and its presentation. However, histopathology of a biopsy revealed tuberculoma and the response to antituberculous therapy was rapid and curative. PMID- 9373560 TI - Vestibular schwannoma showing a dural tail on contrast-enhanced magnetic resonance images. AB - The dural tail on contrast-enhanced magnetic resonance (MR) images, frequently observed in meningiomas, has been used to distinguish between cerebellopontine angle meningiomas and vestibular schwannomas. We report on a 66-year-old female with vestibular schwannoma showing the dural tail on contrast-enhanced MR images. Histological examination revealed that the dural tail corresponded to the thickened dura mater comprising of collagen fibres and scattered hyalinization with no tumoral invasion. PMID- 9373559 TI - Four cases of aggressive MRSA wound infection following head and neck surgery. AB - Four cases of serious MRSA wound infection following head and neck surgery have been identified. One patient died. At post mortem a mediastinal abscess containing MRSA was found to have eroded into the innominate artery causing fatal haemorrhage. The other three suffered serious wound infections, two requiring further surgery. Once MRSA had been identified they were treated with intravenous teicoplanin and all made a full recovery. PMID- 9373561 TI - Inflammatory myofibroblastic tumour of the tonsil. AB - Inflammatory myofibroblastic tumours are aetiologically enigmatic, nosologically confusing and biologically unpredictable lesions. The lungs are the organs of apparent predilection. These tumours have also been documented in a number of extrapulmonary sites including the head and neck. So far only two cases of inflammatory myofibroblastic tumour of the tonsil have been reported in the English literature. We document another case, occurring in a 41-year-old man with history of cadaveric renal transplant nine years ago. A comprehensive review of the literature is also presented. PMID- 9373562 TI - Cystadenoma of the parotid gland with unusual prominent lymphoid stroma. AB - A rare variant of the cystadenoma of salivary gland origin is presented, which occurred in the parotid of a 36-year-old, otherwise healthy female patient. The tumour showed a dense follicle-containing lymphoid stroma, resembling papillary cystadenoma lymphomatosum (Warthin's tumour). In contrast to that, the epithelial lining gave a more irregular impression and oncocytic metaplasia were completely absent. Light microscopic and immunohistochemical features of the tumour are described and compared with those of classical cystadenoma and papillary cystadenoma lymphomatosum (Warthin's tumour). Other relevant multicystic epithelial parotid lesions, which are commonly associated with a prominent lymphoid component are discussed. PMID- 9373563 TI - Irreversible bone loss in former amenorrheic athletes. AB - Small gains in bone mineral density (BMD) have been reported in the first year following resumption of menses in amenorrheic athletes but there have been no long-term outcome studies. The purpose of this study was to determine whether the BMD of former oligomenorrheic or amenorrheic athletes normalizes following several years of normal menses or use of oral contraceptives. Twenty-nine athletes first studied in this laboratory 8.1 years (range 6-10 years) ago were available for follow-up. At recruitment (time 1) 29 athletes, mean age of 30.6 years, were non-smokers, exercised 4 or more days/week for at least 45 min, had not used oral contraceptives, and had no medical conditions affecting bone metabolism. At time 1, 9 women (R/R) had always menstruated regularly, 9 (R/O/A) had experienced intermittent oligo/amenorrhea as well as regular menses, and 11 (O/A) had never menstruated regularly. At follow-up (time 2) mean age of the women was 38.2 years and there were no significant changes in height, weight or activity patterns. BMD (g/cm2) was measured at the lumbar vertebrae (L1-4 and femoral neck by dual-energy X-ray absorptiometry and expressed as a percentage of R/R values. Vertebral BMD was significantly lower in the O/A group compared with the R/R group at both time 1 and time 2 (p < 0.05). The R/O/A group had intermediate values and did not differ significantly from R/R or O/A at either time. Differences in technique between machines for determining femoral neck BMD made it difficult to detect the longitudinal effect of menstrual status at that site. Despite several years of normal menses or use of oral contraceptives, the mean vertebral BMD of former oligo-amenorrheic athletes remained low, being 84.4% of the R/R value compared to 84.8% at time 1. Those experiencing menstrual regularity with intermittent oligo/amenorrhea remained at an intermediate position of 94.7% of the R/R mean. Our results suggest early intervention is necessary to prevent irreversible vertebral bone loss in oligo/amenorrheic athletes. PMID- 9373564 TI - Assessment of the relationship between broadband ultrasound attenuation and bone mineral density at the calcaneus using BUA imaging and DXA. AB - The purposes of this study was to determine the relationship between broadband ultrasound attenuation (BUA) and bone mineral density (BMD) measured at different regions of the calcaneus with identical site-matched regions of interest (ROIs). Dual-energy X-ray absorptiometry (DXA) measurements of the calcaneus and BUA imaging were performed in 30 women (15 premenopausal and 15 postmenopausal). Four square ROIs were located in the great tuberosity and one square ROI in the foramen calcaneus. A ROI adapted to the shape and size of the whole calcaneus was also considered. All ROIs were analyzed three times with both techniques to minimize intra-observer variability. The correlation coefficient between attenuation and frequency was used as an index of BUA measurement error. Before accepting a measurement of BUA in inhomogeneous material, it could be useful to map the spatial variations of the measurement error. In all ROIs we found the BUA and BMD were strongly related (r = 0.78-0.91, p < 0.001). The correlation between BUA and BMD was slightly higher in the inferior part of the posterior tuberosity than in the superior part and in the foramen calcaneus. The very high correlation between attenuation and frequency found in all ROIs (r = 0.99) suggests that measurement errors of propagation were probably not significant. Ultrasound imaging yields the opportunity for studying the spatial acoustic properties in the calcaneus and their relation to bone mass or structural parameters provided by independent imaging techniques. BUA measured with current transmission techniques reflects mainly bone mass, and microarchitecture to a smaller extent. PMID- 9373565 TI - Progesterone-mediated stimulation of osteoprogenitor proliferation and differentiation in cell populations derived from adult or fetal rat bone tissue depends on the serum component of the culture media. AB - We have shown previously that progesterone (Prog) and dexamethasone (Dex) stimulate osteoprogenitor proliferation and differentiation in cell populations derived from adult rat vertebrae and in primary cultures of fetal rat calvariae. In these two in vitro systems, osteoprogenitors can be identified by the appearance of colonies of differentiated osteoblasts producing bone (bone nodule formation). Culture conditions supporting proliferation and differentiation of osteoprogenitors include a requirement for the presence of serum in the culture media. Our major interest in the present study was to investigate whether Prog- and Dex-mediated osteoprogenitor proliferation and differentiation was observed to the same degree in different lots of fetal bovine serum (FBS). In addition, we wanted to investigate whether osteoprogenitors present in cell populations derived from fetal calvarial bone and those present in populations derived from adult vertebral bone would respond similarly under the different culture conditions. We found that, in populations derived from adult rat vertebrae, the effects of the serum component of the culture medium on the number of bone nodules induced by Prog and on the dose-dependency of the Prog effect were striking: in culture media containing the most effective serum the number of bone nodules was 22-fold higher than that in the least effective serum. In addition, Prog responses were detectable at 10(-5) M only in some sera but were significant at 10(-7) M in others. The effect of Dex in the adult rat vertebrae-derived populations was much less dependent on the serum used: the number of bone nodules in culture media containing the most effective serum was only 1.3 times greater than that in media containing the least effective serum. In cell populations derived from fetal calvariae, the serum dependence of the Prog response was less pronounced: a 4.3-fold increase over control was observed in the most effective serum, and a 2.4-fold increase in the least effective serum. No effects of the serum component of the culture medium on the Dex response were detectable. Thus, Prog-induced bone nodule formation appears to be strongly dependent on the particular type of FBS used for osteoprogenitors present in bone cell populations derived from adult rat vertebrae but much less so in populations obtained from fetal rat calvariae. Preliminary experiments suggest that the estrogen content of the culture media may be one of the determinants regulating Prog responsiveness of the osteoprogenitors. Dex-induced proliferation and differentiation of osteoprogenitors in bone cell populations derived from both adult rat vertebrae and fetal rat calvariae, on the other hand, did not appear to be strongly dependent on factor(s) present in the FBS component of the culture medium. PMID- 9373566 TI - Meta-analysis of the effectiveness of physical activity for the prevention of bone loss in postmenopausal women. AB - A meta-analysis was done to measure the effect of physical activity on the bone mass of healthy postmenopausal women. All studies published between 1966 and 1996, in French or English, were reviewed for inclusion from Medline search, bibliographies of relevant studies, review articles and books. Studies had to be prospective intervention trials, randomized or not, evaluating the effectiveness of an exercise program of any duration, frequency and intensity, with a control group. Studies had to measure bone parameters and involve healthy postmenopausal women over 50 years of age who were free of symptomatic osteoporosis at the time of study entry. Effect sizes (ES) were calculated for each bone parameter and site measured in every eligible study according to Hedges and Olkin. DerSimonian and Laird's model was used to estimate overall effect sizes when combining studies. All analyses were bone parameter and site specific. Of 217 papers extracted from the literature, 187 did not meet eligibility criteria and 12 others were rejected. The two main reasons for rejection were that both genders were combined in the analyses and no exercise group without drug interaction was present. Eighteen studies were included for meta-analysis. Taking into account the frequency, duration, compliance rate and average age of the subjects, the programs were judged of moderate intensity and focused on walking, running, physical conditioning and aerobics. A significant effect of physical activity was detected on the bone mineral density at the L2-4 level of the lumbar column in studies published after 1991 (ES = 0.8745, p < 0.05). No effect could be seen, however, on forearm and femoral bone mass. Although applied to a small number of studies, this meta-analysis suggests that exercise programs in a population of postmenopausal women over 50 years of age are effective for preventing spinal bone mineral density loss at the L2-4 level. However, such programs do not have any effect on the forearm or femoral bone mass. PMID- 9373567 TI - Long-term quality control of DXA: a comparison of Shewhart rules and Cusum charts. AB - Long-term clinical trials using bone mineral density (BMD) measurements are now commonplace. It is important to maintain a high standard of quality control. In this study two methods of monitoring quality control measurements of dual-energy X-ray absorptiometry (DXA) equipment have been compared using receiver operating curve (ROC) analysis: Shewhart multi-rule charts and Cusum charts. Computer generated faults within daily spine phantom measurements were used. The Charts were then applied to 3 years of quality control data from one machine and the results related to hardware faults, random events and changes in the underlying BMD measurement. In the ROC analysis the Shewhart multi-rule chart performed as well or better than the cusum chart, but the stringency of the rules must be tightened to obtain optimal performance. PMID- 9373568 TI - Differences in hip axis and femoral neck length in premenopausal women of Polynesian, Asian and European origin. AB - There are substantial inter-racial differences in hip fracture incidence. Studies in several different ethnic groups have suggested that differences in the length of the femoral neck may contribute to these. The present study assesses femoral neck and hip axis lengths in three ethnic groups in which it has not been documented previously (Chinese, Indians and Polynesians) and compares these values with those in Europeans. Lengths were measured from dual-energy X-ray absorptiometry scans of the proximal femur in normal premenopausal women (n = 225). The Polynesian (1.65 m) and European (1.64 m) women were significantly taller than the two Asian groups (mean height in each, 1.58 m). There were also differences in mean body weight, the Polynesians being the heaviest (76 kg) and the Chinese the lightest (53 kg). Femoral neck lengths were (mean +/- SD) Chinese 61.5 +/- 4.4 mm, Indian 61.5 +/- 5.1 mm, Polynesian 68.2 +/- 4.3 mm and Europeans 66.0 +/- 4.8 mm. Hip axis lengths were Chinese 98.0 +/- 5.6 mm, Indian 94.5 +/- 5.2 mm, Polynesian 106.4 +/- 5.3 mm and European 102.3 +/- 5.3 mm. Each of the other groups were significantly different from the Europeans for both variables and, in general, this remained so after height adjustment. These data suggest that shorter femoral necks are common to the major Asian racial groups. However, in contrast to all other ethnic groups studied, Polynesians have longer femoral necks than Europeans and their low incidence of hip fracture is not explicable, therefore, in terms of their femoral neck length. This suggests that either higher bone density or other more subtle differences in proximal femoral geometry must account for the low hip fracture incidence in Polynesians. PMID- 9373569 TI - Oral contraceptive treatment inhibits the normal acquisition of bone mineral in skeletally immature young adult female monkeys. AB - The purpose of the present study was to determine the effects of oral contraceptive therapy on bone density and serum markers of bone metabolism in a prospective, longitudinal study of young adult female cynomolgus monkeys. Two hundred and seven intact cynomolgus monkeys were randomized to two groups, and fed an atherogenic diet containing either no drug (Control) or a triphasic oral contraceptive regimen (Contraceptive). Measurements of bone density were carried out by dual-energy X-ray absorptiometry at 10-month intervals (0, 10, and 20 months) and serum bone biomarkers were determined at 5-month intervals over the 20-month time course. No significant differences in these variables were observed prior to treatment. Both groups of animals gained bone mineral during the study, indicating that peak bone mass had not been reached at baseline. Contraceptive treated animals gained less spinal (lumbar vertebrae 2-4) bone mineral content and density and less whole-body bone mineral content than Controls over the course of the study. Significant depressive effects of contraceptive treatment on gains in BMC and BMD were observed during each 10-month interval of the study. Bone metabolism was inhibited in the Contraceptive group, as reflected by marked reductions (approximately 40%) in serum osteocalcin and alkaline phosphatase levels along with moderate reductions in serum acid phosphatase and calcium. The results suggest that triphasic oral contraceptive treatment of young adult female monkeys that have not reached peak bone mass inhibits net bone accretion and/or growth by reducing bone metabolism. Thus, prolonged continuous oral contraceptive use in skeletally immature females may lead to a lower peak bone mass--an effect which could increase the risk of fractures in later life. PMID- 9373570 TI - Association between weight cycling history and bone mineral density in premenopausal women. AB - The hypothesis that a history of one or more weight reductions and regains (weight cycling) is associated with lower site-specific bone mineral density (BMD) was examined in 169 premenopausal women, aged 29-46 years. Data on the previous 10-years' weight cycling history, present weight-bearing physical exercise, number of deliveries, present use of contraceptive pills or hormone releasing coils, age at menarche and present menstrual status were collected by a self-administered questionnaire. Dietary intake was calculated from food records. The areal BMD (g/cm2) was measured with dual-energy X-ray absorptiometry (Norland XR-26). The lumbar spine (L2-4) BMD, adjusted to weight and age at menarche (ANCOVA), was 0.062 g/cm2 (95% confidence interval: 0.015 to 0.011 g/cm2; p = 0.01) higher in the non-cyclers (n = 68) than in subjects with reported weight cycling history (n = 101). The corresponding difference for femoral neck BMD was 0.019 g/cm2 (-0.018 to 0.056; p = 0.30), for trochanter BMD 0.013 g/cm2 (-0.025 to 0.05 g/cm2; p = 0.50) and for distal radius BMD 0.022 g/cm2 (0.006 to 0.397 g/cm2; p = 0.008). A pairwise comparison of 34 weight-matched subjects (non cycler vs cycler) gave similar BMD differences as found in the above (ANCOVA) analyses. The results suggest that weight cycling might be associated with lower spine and distal radius BMD. PMID- 9373571 TI - Osteopenia, bone fragility and reflex sympathetic dystrophy syndrome in a man with ureterosigmoidostomy. AB - A 68-year-old man is presented with a reflex sympathetic dystrophy syndrome (RSDS) of the right ankle diagnosed by radiography, magnetic resonance imaging and bone scintiscan. Investigations, including blood tests and bone biopsy, revealed a diagnosis of metabolic acidosis and osteomalacia. These appeared to result from a ureterosigmoidostomy performed 9 years previously for a transitional carcinoma of the bladder. Correction of the metabolic acidosis coincided with improvement in ankle pain. RSDS may be the initial presentation of osteomalacia, which in turn may be caused by the metabolic acidosis resulting from a ureterosigmoidostomy. PMID- 9373573 TI - The influence of porosity and pore size on the ultrasonic properties of bone investigated using a phantom material. AB - Ultrasonic propagation in bone has been investigated using the Leeds Ultrasonic Bone Phantom Material. Phantoms were produced with different porosities in the range of 45-83% and pore sizes of 1.3 and 0.6 mm. The phase velocity at 600 kHz was found to follow a second-order polynomial as a function of porosity. Phase velocity values between 1545 and 2211 m s-1 were measured and found to be largely independent of pore size for a given porosity. The slope of the phase velocity as a function of frequency (dispersion) decreases with increasing porosity. The values obtained from samples having different pore sizes were also similar. The attenuation coefficient and normalized broadband ultrasonic attenuation (nBUA) reached a maximum at about 50%. The normalized attenuation ranged from 6 to 25 dB cm-1 over the porosity range available and consistently showed higher values for the larger pore size. Similarly, the nBUA values were found to be between 14 and 53 dB MHz-1 cm-1, with the values for the larger pore size being roughly 10 dB MHz-1 cm-1 greater than those for the smaller pore size. These findings demonstrate that the Leeds phantom can be used to investigate the effect of structural changes in bone and to aid the understanding of quantitative ultrasound. The results support the assumption that the velocity in trabecular bone is not dependent on pore size but is influenced by the mechanical properties of the bone's constituents and the overall framework, whereas the attenuation and BUA are also influenced by structure. PMID- 9373572 TI - Quantitative ultrasound imaging at the calcaneus using an automatic region of interest. AB - A new approach to measuring bone properties at the calcaneus using ultrasound parametric imaging has recently emerged. However, an additional source of observer-related error is the substantial regional variations in the pattern of ultrasound parameters. The contribution of intra-observer and inter-observer variability to the coefficient of variation can be eliminated using an algorithm which selects the region of interest (ROI) completely automatically. The objective of the present study was the clinical assessment of an automatic ROI for both broadband ultrasonic attenuation (BUA) and speed of sound (SOS) measurement using ultrasound parametric imaging. The automatic ROI was defined as the circular region of lowest attenuation in the posterior tuberosity of the calcaneus. We have tested this algorithm using clinical images of the calcaneus from 265 women. Mean coefficients of variation were 1.6% (95% confidence interval 1.4%-1.9%) and 0.26% (95% confidence interval 0.23%-0.32%) for BUA and SOS respectively (standardized CV was 2.1% for BUA and 2.6% for SOS). Z-scores in an osteoporotic group were -0.61 and -0.52 for BUA and SOS respectively. In healthy women, the age-related decline was -0.50 dB/ MHz per year (0.7%/year) for BUA and -1.2 m/s per year (0.08%/year) for SOS. In the subgroup of healthy postmenopausal women, using stepwise multiple regression, we found that BUA was predicted best by years since menopause (YSM) and weight, with overall model r2 = 0.28; SOS was predicted best by YSM only (r2 = 0.21). Neither the range of biological variation of ultrasound parameters nor the clinical value were affected by the choice of the region of lowest attenuation for measurement. The automatic procedure was totally independent of operator interaction, therefore excluding loss of precision due to intra- or inter-observer variability. The results showed the high precision and robustness of the procedure. These factors make this approach viable for routine clinical use. PMID- 9373575 TI - Guidelines for diagnosis and management of osteoporosis. The European Foundation for Osteoporosis and Bone Disease. PMID- 9373574 TI - Fewer bone histomorphometric abnormalities with intermittent than with continuous slow-release sodium fluoride therapy. AB - To help resolve the uncertainty whether sodium fluoride (NaF) therapy should be given intermittently or continuously, we examined iliac crest bone biopsies (before and after treatment) and fragility fracture rates in 35 intermittently treated (group I) and 69 continuously treated (group C) patients; all received calcium. The following statistically significant results were obtained. Reduction in vertebral fracture rate was similar in the two groups. Trabecular thickness and the structurally more important mineralized thickness increased only in group I. Group I also accumulated less excess osteoid (surface, volume). Mean osteoid thickness did not change in either group because of a bimodal distribution of wide seams with osteoblasts and double tetracycline labels, and thin seams without osteoblasts or labels. Osteoid was lamellar. Osteoid in abnormal sites (within bone marrow or bone, or around osteocytes) was found less frequently in group I. Adjusted apposition rate declined and mineralization lag time increased in both groups because of extended unlabelled osteoid seams. Erosion surface increased only in group C. Hook and/or tunnel erosion was seen less frequently in group I; it was closely associated with osteoid in abnormal sites and correlated with osteoid surface. Extended osteoid surface may have forced osteoclasts to hollow out trabeculae, leaving the empty osteoid shell in marrow. Excess osteoid volume and eroded surface and osteoid and erosion in abnormal sites correlated with bone fragility in group C. We conclude that intermittent therapy is to be preferred because it (1) increased mineralized trabecular thickness, (2) did not cause excessive osteoid accumulation and erosion, (3) showed less osteoid and erosion in abnormal sites and (4) led to a similar reduction in the vertebral fracture rate as did continuous treatment. The question of whether intermittency of therapy has some other effect independent of the cumulative dose of fluoride administered cannot be answered by this study. PMID- 9373576 TI - Interdisciplinary collaboration in hospital palliative care: chimera or goal? PMID- 9373577 TI - Nebulized morphine in the palliation of dyspnoea. AB - Seventeen terminally ill cancer patients with primary or secondary intrathoracic malignancy complaining of breathlessness were treated with nebulized morphine in doses of 20 mg 4-hourly for 48 h. The effect on dyspnoea was evaluated using the Dyspnoea Assessment Questionnaire. Most patients felt less dyspnoeic after 24 h; the effect was maintained, but not improved upon, after 48 h. PMID- 9373578 TI - Oral morphine as symptomatic treatment of dyspnoea in patients with advanced cancer. AB - We report an open, uncontrolled study to evaluate the effectiveness of regular oral morphine as symptomatic treatment of dyspnoea in patients with advanced cancer receiving standard clinical care. Fifteen patients were assessed initially, and then 48 h and 7-10 days after starting treatment with oral morphine or having their dose increased. Dyspnoea, measured on a visual analogue scale (0-100), fell by a median of 14 (95% confidence interval -1.5, 25.5; Wilcoxon statistic 32.0; P = 0.06) in the nine who completed all three assessments. The three patients who died during the study did not show symptomatic benefit and, like the three who withdrew, experienced increased sedation and/or dizziness. Sedation was significantly increased at 48 h; median rise 10.5 (95% confidence interval 7, 25; Wilcoxon statistic 74; P = 0.007). Baseline respiratory function (FEV1, FVC, peak flow) was poor and the patients' respiratory rate was unaffected. Regular, titrated oral morphine may improve dyspnoea in some patients with advanced cancer but can cause significant short term adverse effects. Oral morphine should be given to these patients as a therapeutic trial. Patients should be advised about side-effects and carefully monitored. Larger studies are needed to establish which patients are most likely to benefit and optimal dosage regimens. PMID- 9373579 TI - Disclosure of concerns by hospice patients and their identification by nurses. AB - As part of an evaluation of the training of hospice nurses in communication skills, the selectivity of patients in disclosing their concerns and the ability of nurses to register all the concerns disclosed were studied. Forty-two nurses were recruited from two hospices in the north of England. They were asked to determine and write down patients' current concerns before and after training, and nine months later. Their interviews were tape recorded to permit rating of the concerns disclosed. After each interview a research nurse used a semistructured interview and the Concerns Checklist to elicit patients' concerns. The Spielberger State Anxiety Scale and Hospital Anxiety and Depression Scale were then administered to assess patients' mood. In total, 87 patients were thus assessed. Patients were highly selective in what they disclosed and showed a strong bias towards disclosing physical symptoms. Overall, 60% of concerns remained hidden and concerns about the future, appearance and loss of independence were withheld more than 80% of the time. Patients who were more anxious or depressed were less likely to disclose concerns. The nurses registered only 40% of the concerns disclosed to them at interview, and less than 20% of patients' concerns were identified appropriately. The nurses were selective in the categories of concerns that they registered. Pain, family worries, appetite and weight loss, nausea and vomiting were noted most frequently, while concerns about cancer, bowel function, treatment and emotional worries were not registered. The patients' main concern was identified and recorded in only 45% of cases. Overall, it was found that hospice patients selectively disclosed physical symptoms while nurses did not elicit or register patients' concerns accurately. Nurses therefore need to improve their ability to elicit and register all of their patients' concerns and to pay particular attention to those who are anxious and depressed. PMID- 9373580 TI - Does being religious help or hinder coping with chronic illness? A critical literature review. AB - This paper reviews a number of studies relating to religion and coping with chronic illness, emphasizing those aspects relevant to palliative care. After pointing out that religious and existential needs are common in chronic illness, a critical examination is made of those studies which purport to demonstrate associations between spiritual beliefs, religious practices and psychological prognosis. Recommendations are made as to how religious issues can be dealt with in clinical practice, with particular relevance to the multidisciplinary palliative care team. PMID- 9373581 TI - Existential consequences of unrelieved cancer pain. AB - Seventy-eight cancer patients who were being treated for pain-related problems underwent a semistructured interview concerning the influence of cancer and cancer pain on existential issues. Pain intensity was assessed with visual analogue scales in order to quantify the overall mean pain intensity as well as pain intensity during the best and worst periods. Patients with a higher overall mean pain score (i.e. insufficient pain control) or higher mean worst pain score expressed significantly more fear about the future (P < 0.01), worries about pain progression (P < 0.05) and general anxiety that hampered their daily living (P < 0.05). Younger patients expressed more fear of pain progression and of the future in general and they were much more concerned about the future of their families (P < 0.05). The fear of future pain problems was related to the duration of the pain (P < 0.01). In conclusion, partly unrelieved pain contributes to the 'total pain' experience, not only by causing immediate physical suffering, but also by increasing the anxiety level and the fear about the future and future problems. The study underlines that effective symptom control is a prerequisite for a good quality of life: pain control is a matter of the highest priority. PMID- 9373582 TI - Problems of anticoagulation within a palliative care setting: an audit of hospice patients taking warfarin. AB - Patients with cancer have an increased risk of venous thromboembolism (VTE) compared with a healthy population. The risk increases as cancer progresses and this is reflected in the number of hospice inpatients with VTE. These patients also have an increased risk of bleeding due to tumour site, complications of treatment, progressive liver involvement and concurrent medication such as nonsteroidal anti-inflammatory agents. Therefore anticoagulation of cancer patients with VTE is fraught with difficulty. This audit of hospice inpatients taking warfarin showed a high incidence of bleeding which was possibly improved with very stringent international normalized ratio (INR) monitoring: 15 episodes in 17 patients improved to 11 episodes in 18 patients. Patient numbers were small and the two groups heterogeneous, thus formal statistical analysis could not be applied. One patient in each group continued to thrombose despite over anticoagulation with warfarin. Monitoring of INR increased from an average of once every six days to once every 2.4 days. Such frequent monitoring is likely to be highly impractical in many hospice and general practice settings. Control of warfarin as measured by average percentage of INRs in, above or below the therapeutic range if anything appeared to be worse in the second group. Any bleeding in these patients was distressing. As a result of this audit, practice in Huntershill Marie Curie Centre has changed. Low molecular weight heparins are proven to be efficacious in the treatment of VTE, are renally excreted and therefore do not interact with many commonly used concurrent medications. They can be administered once daily and do not need monitoring of anticoagulant effect. Thus they will be used in patients for whom anticoagulation is indicated during a six-month period, after which practice will be again reviewed. PMID- 9373583 TI - The incidence of suicide in palliative care patients. AB - Anecdotal reports from hospices show a low incidence of suicide, yet depression is increased in cancer patients, and the likelihood of suicide is increased in depressed patients. Suicide would be expected to be more common in terminally ill patients. A postal survey was undertaken of 43 palliative care units. They were asked to report the number of suicides, parasuicides and the total number of referrals for the five-year period from 1990 to 1994. Thirty-four units replied (79%). Complete data were available from 24 (56%) units. Total referrals were 72,633 in the five-year period. Nine units (38%) had one or more suicides, with a total of 21 suicides reported. Sixteen units (67%) had one or more attempted suicides (total 37). There are implications in the study both for direct patient care, but also data collection, staff support and training. PMID- 9373584 TI - The General Medical Council and the right to specialist palliative care. PMID- 9373585 TI - Training abroad: a worthwhile experience. PMID- 9373586 TI - Ethical issues in qualitative research in palliative care. PMID- 9373587 TI - Topical morphine for cutaneous cancer pain. PMID- 9373588 TI - Single-question assessment of quality of life. PMID- 9373589 TI - The syndrome of motor restlessness--a treatable but under-recognised disorder. PMID- 9373590 TI - Spontaneous pneumoperitoneum and other nonsurgical causes of intraperitoneal free gas. AB - Intraperitoneal free gas seen radiologically as air under the diaphragm nearly always indicates a perforated abdominal viscus that requires surgical intervention. Rarely, however, the presence of a pneumoperitoneum may not indicate an intra-abdominal perforation and thus may not require laparotomy. Such a situation is termed spontaneous or nonsurgical pneumoperitoneum. In this review, we explore the aetiological mechanisms and the pathophysiology of the appearance of intra-abdominal free gas. An appreciation of the condition and its likely aetiological factors should improve awareness and possibly reduce the imperative to perform an emergency laparotomy on an otherwise well patient with an unexplained pneumoperitoneum. PMID- 9373592 TI - Chronic pancreatitis and pancreatic carcinoma. AB - The differential diagnosis between pancreatic cancer and chronic pancreatitis is very important as the management and prognosis of these two diseases is different. In most patients with pancreatic disease, the diagnosis can be established but there is a subgroup of patients in whom it is difficult to differentiate between these conditions because the clinical presentation is often similar and currently available diagnostic tests may be unable to distinguish between an inflammatory or neoplastic pancreatic mass. This paper reviews the aetiology, pathology and clinical features of these diseases and discusses the limitations of conventional diagnostic methods and how newer techniques may be of value in the differential diagnosis. PMID- 9373591 TI - Basal cell carcinoma. AB - Basal cell carcinoma is the commonest malignancy in Caucasians with incidence rates of 300 per 100,000 reported in the USA. Rates are increasing at over 10% per year leading to a lifetime risk of 30%. Although mortality is low, the disease is responsible for considerable morbidity and places a substantial burden on health service provision in the UK. Furthermore, lesions may recur and patients often develop multiple tumours giving major implications for treatment and follow-up. Four main types of basal cell carcinoma are seen: nodulo ulcerative; pigmented; morpheaform and superficial. Diagnosis is by histological evaluation although many tumours have a characteristic clinical appearance. The differential diagnosis is large. Identified risk factors include male gender, skin type 1, red/blonde hair and increasing age. Patients with basal cell carcinoma are more likely to develop malignant melanoma and squamous cell carcinoma but it is still unclear whether there is a link with internal malignancy. The main treatment modalities are surgery and radiotherapy. Each has advantages and disadvantages. The choice of treatment depends on many factors. Principles of treatment include identification of high-risk patients to enable early detection, complete removal of the lesion, and careful follow-up to detect recurrence or new lesions. Approximately 10% of tumours recur, depending on site, size and treatment modality. Metastatic basal cell carcinoma and the association of ultraviolet radiation to basal cell carcinoma risk are reviewed. PMID- 9373593 TI - Moyamoya disease. AB - Moyamoya disease is a rare cerebrovascular condition of uncertain aetiology commonly affecting young persons. The disease is mainly seen in Japanese patients. We report two cases of moyamoya disease in Caucasian women and review the postulated aetiological factors and associated conditions as well as the spectrum of invasive and non-invasive imaging modalities useful in the diagnosis and follow-up of the disease, with particular reference to the developing role of magnetic resonance imaging and angiography. PMID- 9373595 TI - Creutzfeldt-Jakob disease in the elderly. AB - Creutzfeldt-Jakob disease (CJD) is typically described as a pre-senile dementia. However, cases do occur in the elderly and a case of sporadic CJD in an 86-year old patient is described. The database of the UK national surveillance unit has been studied, and the age-specific incidences for various age groups over the period 1980-93 calculated. Cases of CJD in those over 80 years old have been identified and their clinical characteristics examined. There is no evidence that CJD presents atypically in the elderly, or that large numbers of cases are being missed in the elderly due to poor ascertainment. PMID- 9373594 TI - The andropause: fact or fiction? AB - The so-called andropause is an ill-defined collection of symptoms in a group of men who may have low but may also have normal androgen levels. Unlike the proven benefits of hormone replacement therapy in women, the effects of testosterone supplementation in men are equivocal. It may increase sexual interest, but rarely to a level thought adequate by the patient. It has no proven beneficial effect on erectile dysfunction and other possible beneficial effects on haemopoesis, bone metabolism, lipids and fibrinolysis have yet to be demonstrated. With the availability of the testosterone patch, sustained increases in the serum testosterone levels will be readily achieved and could theoretically significantly affect the behaviour of subclinical prostate cancer. At the present time, testosterone replacement therapy in hypogonadal men is of proven clinical benefit; this is not the case, however, for eugonadal men with symptoms attributed to the andropause. The symptoms of the andropause fatigue can readily be explained by stress and there is no scientifically valid, placebo-controlled study that shows any benefit for testosterone supplements in this not uncommon group of patients. PMID- 9373596 TI - Management options for solitary thyroid nodules in an endemic goitrous area. AB - An analysis of management of 546 cases of solitary thyroid nodules in an endemic area is presented. None of the evaluating procedures could effectively isolate benign from malignant disease. Of 508 cases considered clinically to be benign, 42 harboured malignancy on histological examination whereas of the 38 cases suspected clinically to be malignant, 21 were histologically benign. 131I-Thyroid scanning also lacked sensitivity in identifying malignant nodules since the prevalence of malignancy in cases which were 'cold' (44/316) was not significantly different from that amongst the 'uniform' cases (15/142). Fine needle aspiration cytology, although the most sensitive and specific evaluating modality, did not decrease the number of operations for solitary thyroid nodules nor did it increase the incidence of malignancy amongst the operated cases, because of its limitations in differentiating benign from malignant follicular neoplasms. The conditions under which surgery was advocated are described. PMID- 9373597 TI - Microbiologically proven bacterial infections in AIDS. AB - We have reviewed the incidence, type and site of microbiologically proven bacterial infection occurring in 52 patients with the acquired immunodeficiency syndrome (AIDS) who presented to Southmead Hospital, Bristol between 1990 and 1994. A total of 30 (58%) patients had significant bacterial isolates. The majority of infections were community acquired. Overall, more infections were caused by Gram-negative organisms but Gram-positive organisms predominated in bacteraemia. Mycobacterium avium intracellulare (MAI) caused infection in the largest number of patients, followed by Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas sp, and Campylobacter sp. When individual episodes of infection were considered, after MAI, Haemophilus influenzae, Streptococcus pneumoniae and Pseudomonas sp were the organisms most frequently isolated; often these same organisms caused recurrent chest infection. Bacterial infections in AIDS patients are common and although they generally respond well to antimicrobial chemotherapy there is a high recurrence rate, particularly in the respiratory tract, which is the commonest site of infection. PMID- 9373599 TI - Rapid diagnosis of asymptomatic hereditary haemochromatosis by detection of the Cys282Tyr mutation in the HLA-H gene. AB - Hereditary haemochromatosis is an autosomal recessive disorder characterised by life-long excessive accumulation of iron. A candidate gene for hereditary haemochromatosis has recently been reported (HLA-H) and a specific missense mutation (Cys282Tyr) has been identified in 85% of patients with the disorder. We describe the rapid detection of this mutation using the polymerase chain reaction and restriction endonuclease digestion. The usefulness of this test for early diagnosis of hereditary haemochromatosis in asymptomatic family members is highlighted. PMID- 9373598 TI - Regression of cardiac involvement by malignant melanoma following lomustine chemotherapy. AB - Cardiac involvement by malignant melanoma is usually a premorbid event. We present a case of presumed cardiac involvement by malignant melanoma with regression following chemotherapy as demonstrated by transoesophageal echocardiography. PMID- 9373600 TI - Hippocratic fingers in Behcet's disease. AB - Digital clubbing has been a well recognised feature of several distinct clinical conditions, including respiratory, cardiac, and gastrointestinal diseases since the Hippocratic era. However, clubbing associated with Behcet's disease has not been reported before. We describe a case of clubbing in a young man with Behcet's disease, in the absence of any other apparent aetiology and propose that clubbing might be an accompanying feature of Behcet's disease. PMID- 9373602 TI - Association of sarcoidosis, low-grade B-lymphoma and epidermoid carcinoma. AB - We report on a case of the so-called sarcoidosis-lymphoma syndrome in a 65-years old man diagnosed as having sarcoidosis and, four years later, neurosarcoidosis. The diagnoses of epidermoid carcinoma of the skin and of stage IV monocytoid, small cell lymphocytic lymphoma were made five and seven years, respectively, after the initial diagnosis of sarcoidosis. It has been suggested that the increased mitotic activity of lymphocytes observed in sarcoidosis, favours their malignant transformation. Hypothetically, sarcoidosis might also influence the development of epidermoid carcinomas by depletion of circulating T4 lymphocytes and decreased resistance to oncogenic viruses that could lead to decreased tumour rejection in the epithelia exposed to carcinogenic stimuli. PMID- 9373601 TI - Missed curable carcinoma of the pancreas presenting as chronic pancreatitis. AB - We present a case of pancreatic malignancy which presented as chronic pancreatitis. The diagnostic difficulties are discussed. We recommend that when there is any doubt about a diagnosis of chronic pancreatitis with a pancreatic mass, then early resection is appropriate. PMID- 9373603 TI - Renal cell carcinoma with solitary metastases appearing during 18 years of follow up. PMID- 9373604 TI - Coma during Salmonella typhimurium septicaemia. PMID- 9373605 TI - Abnormal abdominal CT scan following cholecystectomy. PMID- 9373606 TI - Penile gangrene in lung cancer. PMID- 9373607 TI - Abdominal retroperitoneal lymphadenopathy in an elderly man. PMID- 9373608 TI - Self-induced myopathy. PMID- 9373609 TI - A complication of a long-standing solitary lung cyst. PMID- 9373610 TI - Asymptomatic murmurs. PMID- 9373611 TI - Constitutional syndrome and lumbar pain. PMID- 9373612 TI - More than an ankle sprain. PMID- 9373613 TI - Methotrexate pneumonitis in a patient with rheumatoid arthritis. PMID- 9373614 TI - Post-prandial syncope due to nitrates in food. PMID- 9373615 TI - Hyperhomocysteinaemia. PMID- 9373616 TI - Treatment of 'warfarin intolerance'. PMID- 9373617 TI - Presentation of Plasmodium vivax malaria. PMID- 9373619 TI - Arachidonate 12-lipoxygenases. PMID- 9373618 TI - The isoprostanes: unique bioactive products of lipid peroxidation. AB - The discovery of IsoPs as products of non-enzymatic lipid peroxidation has opened up new areas of investigation regarding the role of free radicals in human physiology and pathophysiology. The quantification of IsoPs as markers of oxidative stress status appears to be an important advance in our ability to explore the role of free radicals in the pathogenesis of human disease. A drawback related to this, however, has been lack of more facile and less expensive methods than mass spectrometry for the measurement of IsoPs. On the other hand, the recent introduction of immunoassay methods for measurement of IsoPs may alleviate this problem, provided they are specific and reliable. If this is the case, immunoassay methodology will most likely lead to an expansion of the use of measurements of IsoPs to assess oxidative stress status in vivo. Another need in the field of free radical medicine is information regarding the clinical pharmacology of antioxidant agents. Because of the evidence implicating free radicals in the pathogenesis of a number of human diseases, large clinical trials are planned or underway to assess whether antioxidants can either prevent the development or ameliorate the pathology of certain human disorders. However, data regarding the most effective doses and combination of antioxidant agents to use in these clinical trials is lacking. As mentioned previously, administration of antioxidants suppresses the formation of IsoPs, even in normal individuals. Thus, measurement of IsoPs may provide a valuable approach to defining the clinical pharmacology of antioxidants. In addition to being markers of oxidative stress, at least two IsoPs possess potent biological activity. The availability of additional IsoPs in synthetic form should broaden our knowledge concerning the role of these molecules as mediators of oxidant stress. Moreover, information regarding the nature of the receptor(s) that mediate the biological actions of IsoPs will be of considerable importance to the development of specific antagonists or agonists of the biological actions of IsoPs. Despite the fact that considerable information has been obtained since the initial report of the discovery of IsoPs, much remains to be understood about these molecules. With continued research in this area, we believe that much new information will emerge that will open up additional important new areas for future investigation. PMID- 9373620 TI - Regulation of fatty acid synthase (FAS). PMID- 9373621 TI - Fatty acid activation. PMID- 9373622 TI - Genetic susceptibility to multifactorial diseases. PMID- 9373623 TI - Royal Society of Tropical Medicine and Hygiene meeting at Manson House, London, 17 October 1996. Debate: tropical medicine as a formal discipline is dead and should be buried. PMID- 9373624 TI - Host choice by indoor-resting Anopheles arabiensis in Ethiopia. AB - The host preference of indoor resting Anopheles arabiensis has been determined using a direct enzyme-linked immunosorbent assay. A total of 611 specimens, 258 from human dwellings, 179 from mixed dwellings, and 174 from cattle sheds, was examined. The proportion of human blood meals identified was highest from mosquitoes caught in human dwellings (91.5%), followed by those from mixed dwellings (20.2%) and cattle sheds (3.5%) (P < 0.0001). The smaller proportion of human blood meals from mixed dwellings suggests that cattle may protect humans from A. arabiensis. PMID- 9373625 TI - A survey for antibodies to Lassa virus among health workers in Nigeria. AB - A study was conducted among 552 health workers at 6 health facilities in Nigeria. Lassa virus immunoglobulin (Ig) G antibody was detected in 12.3%, using an enzyme linked immunosorbent assay. Antibody prevalence in the 6 health centres ranged from 1.2% to 27.3%. Prevalences were higher in primary and secondary health facilities than in tertiary centres. Seroprevalences ranged from 1.7% to 23.7% among different occupational groups of health workers; the highest observed antibody prevalence was among ward aids. Lassa virus IgM antibody, indicating recent infection, was present in 6 of the health workers, 5 of whom were ward aids and one was a nurse. All of the health workers with specific IgM came from a single facility in Lafia, sampled during an outbreak of Lassa fever. PMID- 9373626 TI - Changes in abundance and behaviour of vector mosquitoes induced by land use during the development of an oil palm plantation in Sarawak. AB - Surveys were conducted of adult and immature mosquitoes in an area undergoing oil palm development in north Sarawak. Point prevalence data from 2 sites were collected annually, coinciding with annual phases of forest clearing, burning/cultivation, and maintenance. Major habitat perturbation during the forest/clearing transition shifted the major mosquito faunal equilibrium in terms of species composition, relative density and occurrence. Analyses of variance showed that the mean numbers of 4 species of Anopheles decreased significantly after forest clearing. Relative densities of immature stages decreased after forest clearing, but A. letifer and Culex tritaeniorhynchus remained relatively unchanged after the second year. Comparisons with the pre-development forest stage showed that the reductions in person-biting rates, adult survival and combined entomological inoculation rates (EIR) of A. donaldi and A. letifer decreased the risk of malaria transmission by 90% over the 4 years period. Concomitant reductions in EIR and annual malaria incidence were also correlated. This study highlighted the 'law of unintended consequences', since 2 contrasting effects were observed: reduction of malaria vectors but concomitant increase of dengue vectors. PMID- 9373627 TI - The bionomics of Anopheles funestus and its role in malaria transmission in a forested area of southern Cameroon. PMID- 9373629 TI - Sporadic hepatitis E in southern India. PMID- 9373628 TI - Prevalence of cysticercosis in epileptics and members of their families in Burundi. AB - In the province of Bururi in Burundi, 103 epileptics and 72 control subjects from the same households were examined for cysticercosis. Antigen was detected by enzyme-linked immunosorbent assay in 4.9% of epileptic persons and in 4.2% of controls. Antibody was detected by enzyme-linked electroimmunotransfer blot assay (EITB) in 11.7% of epileptics and in 2.8% of controls. Neither difference was statistically significant, nor was a history of taeniasis significantly more frequent in epileptics than in controls. However, cysticercosis was significantly more frequently diagnosed by EITB in people with a history of taeniasis than in those without such a history. The prevalence of taeniasis in schoolchildren ranged between 0 and 1.0%. Meat inspection detected cysticercosis in 2% and 39% of pigs in 2 localities, respectively. PMID- 9373630 TI - Seroepidemiological study of Helicobacter pylori infection in South African children. AB - The seroepidemiology of Helicobacter pylori infection was studied in 681 randomly selected Black children from newborn to 13 years of age (333 boys, mean age 8.05 years, and 348 girls, mean age 7.76 years) in KwaZulu/Natal, South Africa. H. pylori infection was identified serologically using an enzyme-linked immunosorbent assay to detect the presence of immunoglobulin G against H. pylori. Demographic information collected included age, gender, family income, overcrowding, educational level, and possession of domestic pets. The seroprevalence of H. pylori infection was compared to a known faecal-orally transmitted infection, hepatitis A virus (HAV); 66% of the children were seropositive for H. pylori. There was an age-specific increase in H. pylori infection, with more than 80% of children being infected by the age of 10 years. There was no significant difference (P = 0.338) in the seropositivity of H. pylori infection between boys (68%) and girls (64%), nor was there any significant difference in H. pylori infection related to pets, level of parents' education, crowding, and income, by either univariate or multivariate analysis. However, there was a significant association (P < 0.00001) between the seroprevalence of H. pylori and HAV infections, suggesting similar modes of transmission. PMID- 9373631 TI - Malaria diagnosis by field workers using an immunochromatographic test. AB - A rapid immunodiagnostic test (ICT Malaria PfTest) has been developed by ICT Diagnostics (Sydney, Australia) for the diagnosis of Plasmodium falciparum infection. The test is an antigen capture assay based on the detection of P. falciparum histidine-rich protein 2 in peripheral blood. This study was undertaken to assess the performance and usefulness of the test as a diagnostic method in highly malarious, inaccessible forested villages of Mandla district, central India. In all, 353 patients with fever were scanned by the test in parallel with thick blood film examination. The sensitivity and specificity were 100% and 84.5%, respectively. The whole test took about 5 min. The test results became negative in most cases (70%) within 7 d after initiation of curative chemotherapy. The test is simple, easy to learn and accurate, and may prove to be an important tool in the battle against falciparum malaria. PMID- 9373633 TI - The ParaSight-F rapid dipstick antigen capture assay for monitoring parasite clearance after drug treatment of Plasmodium falciparum malaria. AB - Three methods for the detection of Plasmodium falciparum infection in peripheral blood were compared during antimalarial treatment and follow-up in 32 Burundian patients: dipstick antigen capture assay, standard (TBF) and prolonged thick blood film examination (PTBF) (3 x 5 min and 3 x 20 min examination respectively). Parasitaemia was determined daily by comparison with total white blood cell counts (determined by Coulter counter) until no parasite was detected on 2 consecutive days by PTBF. Cumulatively, 231 observations were made with each assay: 64 were negative and 167 positive by PTBF (59 had parasite counts < or = 100/microL). Compared to PTBF, the sensitivities of TBF and the dipstick assay were 1.0 for parasite counts > 100/microL and 0.458 and 0.966 respectively for counts < or = 100/microL. Overall, the dipstick assay was significantly more sensitive (0.988 vs. 0.808; P < 0.001) but less specific (P = 0.013) than TBF. The dipstick assay is of potential use for monitoring response to drug treatment and for detecting low parasitaemias. PMID- 9373632 TI - The ParaSight-F dipstick test as a routine diagnostic tool for malaria in Sri Lanka. AB - Blood from 1053 persons who presented for treatment at outpatient clinics of government health institutions in Sri Lanka, and 250 who took part in a blood survey for malaria, was examined by thick blood film microscopy under routine field conditions, and by the ParaSight-F dipstick method. All the samples were also examined microscopically under laboratory conditions when 4 times the number of microscope fields were examined. Compared with this reference standard, the sensitivity and specificity of the ParaSight-F test were 90.2% and 99.1%, and those of microscopy in the field were 92.4% and 98.4% respectively, there being no statistically significant difference between the 2 methods. The ParaSight-F test reading correlated significantly and positively with the intensity of clinical disease of patients but not with their peripheral parasitaemia, indicating that it may be a more accurate measure of the true parasite load than microscopy, which detects only parasites which are in the peripheral blood and not those which are sequestered in deep organs. The ParaSight-F test, however, failed to detect Plasmodium falciparum infections with only gametocytes in the blood (19.6% of the infected blood samples in this study). The time taken for a patient to revert to negativity by the ParaSight-F test was also significantly longer, up to 14 d. This would make the test unsuitable for checking the response to antimalarial treatment within 14 d. In an endemic area it would therefore fail to detect drug resistant populations of parasites. PMID- 9373634 TI - Evaluation of a non-isotopic polymerase chain reaction-based assay to detect and predict treatment failure of Plasmodium vivax malaria in travellers. AB - With the emergence of chloroquine-resistant Plasmodium vivax (CRPV), new tests to detect P. vivax and predict response to therapy would be useful for clinical and research applications. We performed a 'blinded' evaluation of a non-isotopic (colourimetric) polymerase chain reaction (PCR) based assay (Digene SHARP Signal System) compared with microscopy and PCR/radiometric probe hybridization of ribosomal ribonucleic acid genes (RPH) for the detection of P. vivax malaria in 182 febrile travellers. Compared with PCR/RPH as the reference standard, the colourimetric assay had a sensitivity of 100% and specificity of 98%. Using microscopy as the reference standard, 84 of 87 patients with P. vivax infection had a positive colourimetric assay. The 3 patients with a negative assay were subsequently shown to be infected with P. ovale as determined by PCR/RPH. In a subset of patients followed longitudinally, the colourimetric assay was positive in 5 of 13 patients 6 or more days after initiation of therapy. Of these 5 patients, 4 were subsequently demonstrated to be infected with CRPV as determined by treatment failure in vivo and/or chloroquine blood levels. A positive assay result 6 or more days after initiation of therapy was associated with subsequent treatment failure (P < 0.01). This non-isotopic assay is a sensitive, specific, and rapid method for the detection of P. vivax PCR products and may prove useful in predicting treatment failure. PMID- 9373635 TI - Diagnosis of Plasmodium malariae infection by the polymerase chain reaction. PMID- 9373636 TI - Polypropylene fibre web, a new matrix for sampling blood for immunodiagnosis of schistosomiasis. AB - Blood sampling on filter paper is widely used for immunodiagnostic and epidemiological purposes. However, elution of conventional filter papers impregnated with sera containing Schistosoma mansoni circulating anodic antigen (CAA) recovered only a small fraction of the antigen, thereby reducing the sensitivity of the assay. Polypropylene-based non-woven fibre web is a new sampling material with a low density of fibres and with a small surface area of contact. When it was impregnated with serum containing CAA, approximately 90% of the antigen could be extracted. The yield of antibodies against S. mansoni from the new sampling material did not differ from that from conventional filter papers. PMID- 9373637 TI - Screening pulmonary tuberculosis suspects in Malawi: testing different strategies. AB - Alternative strategies for screening tuberculosis (TB) suspects are needed in sub saharan Africa. Ambulatory adult TB suspects who were seen in the chronic cough room of Queen Elizabeth Central Hospital, Blantyre, Malawi, were assessed with respect to appropriateness of referral. Appropriate referrals (patients with cough 3 weeks or longer, weight loss and no antibiotic response) were screened by 3 sputum specimens for microscopy and culture of Mycobacterium tuberculosis and chest radiography (CXR). Hypothetical strategy A (screening by sputum smear examination followed by CXR in patients with negative sputum smears) was compared with strategy B (screening by CXR followed by sputum smear examination in patients with a CXR consistent with TB) in terms of diagnostic efficacy and cost. Of 1127 patients referred to the cough room, 402 (38%) were appropriate TB suspect referrals. Of these, 111 (28%) were sputum smear-positive, 213 (53%) were culture-positive, and 221 (55%) had smear and/or culture-positive evidence of TB. Routine CXR was consistent with pulmonary (P) TB in 230 patients (57%). With strategy A, 243 (60%) patients were diagnosed as PTB, but 40 (25%) of those not diagnosed as PTB had positive mycobacterial cultures. With strategy B, 230 patients (57%) were diagnosed as PTB, but 53 (31%) of those not diagnosed as PTB had positive mycobacterial cultures, including 13 with smear-positive sputum. The cost per diagnosed case of PTB was US$ 4.63 with strategy A and US$ 5.44 with strategy B. Screening patients with good criteria of TB has high diagnostic sensitivity, but screening by CXR is less effective and more costly than screening by sputum smear microscopy. PMID- 9373638 TI - Diagnosing tuberculosis in a resource-poor setting: the value of sputum concentration. AB - Diagnosis of tuberculosis in resource-poor settings is hampered by the insensitivity of the direct Ziehl-Neelsen (ZN) smear. Liquefaction and concentration of sputum before preparing a ZN smear has been proposed as a way of increasing diagnostic sensitivity. A field trial of this technique was done in a district hospital in South Africa among 166 consecutive tuberculosis suspects. Correlation between the 2 types of smear was high, but the extra cases diagnosed after concentration was offset by a similar number that, initially positive, were negative after concentration. Overall diagnostic sensitivity of smear microscopy was not increased by sputum liquefaction and concentration. The value of this technique may lie in combining it with direct microscopy. Limiting specimen examination to one per patient and making an initial direct smear with subsequent concentration only if the direct smear was negative increased sensitivity from 43% to 55% without any reduction in specificity. However, overall diagnostic sensitivity remained disappointing. PMID- 9373640 TI - Comparative evaluation of four serodiagnostic tests for scrub typhus in Thailand. AB - The commercial dot-blot enzyme-linked immunosorbent assay Dip-S-Ticks dipstick test was compared with the indirect immunoperoxidase (IIP) and Weil-Felix (WF) tests for the diagnosis of scrub typhus, using the indirect immunofluorescent antibody test (IFA) as the reference standard. With a panel of 117 positive and 75 negative sera, the dipstick test was 94% sensitive and 98.7% specific at a cut off value of one or more positive dots. The IIP was 90.6% sensitive and 100% specific at a cut-off titre of 1:400, and was more sensitive than the IFA with acute sera (79.6% vs. 68.5% at a titre > or = 1:400). All 3 were superior to the WF, which lacked sensitivity. The dipstick assay was easy to perform and did not require sophisticated electrical equipment, and the results were available within one hour. It is therefore suitable for use in rural Thailand, where scrub typhus is common. PMID- 9373639 TI - Diagnosing tuberculosis in a resource-poor setting: the value of a trial of antibiotics. AB - Diagnosis of smear-negative but culture-positive pulmonary tuberculosis in resource-poor settings is difficult. To determine the value of assessing response to a trial of antibiotics in the identification of patients with positive cultures but negative Ziehl-Neelsen (ZN) smears, we compared clinicians' diagnoses with culture in 334 consecutive adults with suspected tuberculosis in rural South Africa; 142 patients (43%) had culture-positive pulmonary tuberculosis. Diagnosis by ZN smear alone was insensitive (61%) but highly specific (94%). Only half of the smear-negative but culture-positive cases were correctly identified by failing to respond to a broad spectrum antibiotic. The remainder responded to therapy and were discharged. Diagnostic sensitivity therefore increased to 80%, but specificity fell to 78%. A more rigorous algorithm may improve diagnosis of smear-negative pulmonary tuberculosis in resource-poor settings. PMID- 9373641 TI - Hyperreactive malarious splenomegaly: immunohistochemical demonstration of Plasmodium falciparum antigen in liver cells. PMID- 9373642 TI - Plasmodium falciparum persists in the placenta after three days' treatment with quinine. PMID- 9373643 TI - Chagas disease: mononuclear cell infiltration but no trypanosomes in the coronary sinus and cardiac veins of chronic patients. PMID- 9373644 TI - Serum and tissue nitrate levels in murine visceral leishmaniasis correlate with parasite load but not with host protection. AB - Nitrate levels were measured in serum and in organs from Lshs BALB/c and Lshr C3H/HeN mice during the acute phase (30 d) of infection by Leishmania donovani strain LV9. Serum nitrate levels increased rapidly in BALB/c mice from a baseline level (17 +/- 4 mumol/L) to a plateau (504 +/- 129 mumol/L) at 24 d and correlated with parasite loads in the liver (r = 0.817, P < 0.01) and in the spleen (r = 0.854, P < 0.001). Liver and spleen nitrate contents were enhanced 2.7-fold and 22.8-fold, respectively, with respect to uninfected controls (2692 +/- 249 vs. 992 +/- 231 nmol, P < 0.02 and 20 +/- 1 vs. 456 +/- 43 nmol, P < 0.02). In contrast, serum nitrate increased to a lesser extent in C3H/HeN mice, from 31 +/- 5 mumol/L to 86 +/- 5 mumol/L at 20 d. Liver nitrate content did not differ significantly between infected and control mice (1093 +/- 83 vs. 867 +/- 104 nmol), whereas the former had a higher spleen nitrate content (145 +/- 22 vs. 40 +/- 2 nmol, P < 0.02). Our findings indicate that production of NO by the susceptible BALB/c strain exceeded that of the resistant C3H/HeN strain during the acute stage of infection by L. donovani. Tissue NO overproduction in organs infected by L. donovani was related to the progression of parasitic disease and contributed to high nitrate serum levels. It would be very interesting to extend this investigation to human disease with the aim of evaluating serum nitrate as a marker of parasite load in the follow-up of patients suffering from visceral leishmaniasis. PMID- 9373645 TI - Anal ulcer and chronic diarrhoea as manifestations of visceral leishmaniasis in a patient infected with human immunodeficiency virus. PMID- 9373647 TI - Dermotropic isolates of Leishmania infantum in Iran. PMID- 9373646 TI - Oral leishmaniasis in an HIV-positive patient caused by two different zymodemes of Leishmania infantum. PMID- 9373648 TI - Schistosoma haematobium: an unusual clinical presentation. PMID- 9373649 TI - Circulating connective tissue metabolites in patients with bancroftian filariasis. AB - Sera from adults from an area of Tanzania with high endemicity for Wuchereria bancrofti infection were examined for 4 serological markers of extracellular matrix activity, namely the amino-terminal propeptide of type III procollagen (PIIINP), the carboxy-terminal propeptide of type I procollagen (PICP), the carboxy-terminal telopeptide of type I collagen (ICTP), and hyaluronan. Sera from individuals with non-filarial elephantiasis and from healthy Danes were included as controls. No association was observed between the mean serum concentration of PIIINP or PICP and the clinical, microfilarial or circulating filarial antigen status of the individuals. The mean concentration of ICTP was significantly higher (P < 0.01) in sera from individuals with filarial and non-filarial elephantiasis than in sera from individuals living in filariasis endemic areas but without elephantiasis or in the Danish control sera. Among individuals from the filariasis endemic area, the mean serum concentration of hyaluronan was significantly higher (P < 0.01) in microfilaraemic than in amicrofilaraemic individuals, and significantly higher (P < 0.01) in individuals who had circulating filarial antigens than in those who did not, but there was no relation to the clinical status. The significance of the findings are discussed in relation to the pathological processes taking place in bancroftian filariasis. PMID- 9373650 TI - Scarification as a risk factor for rapid progression of filarial elephantiasis. PMID- 9373651 TI - Long-term follow-up of konzo patients. AB - Nine patients with konzo, a symmetric spastic paraparesis of acute onset that occurs during agricultural crises in cassava-growing areas, were re-examined after 14 years. Konzo outbreaks are associated with eating insufficiently processed bitter cassava and a low intake of essential amino acids. Bitter cassava contains cyanogenic glycosides; processing breaks them down to acetone cyanohydrin and hydrogen cyanide. This long-term follow-up showed that the neurological signs in konzo patients remained constant. Four severely affected patients, however, showed functional improvement. This non-progression clearly distinguishes konzo from myelopathy associated with human T lymphotropic virus type I infection. One child, originally classified as a konzo case, showed signs of cretinism at follow-up. PMID- 9373652 TI - Polymorphism of the Pfmdr1 gene and chloroquine resistance in Plasmodium falciparum in The Gambia. AB - To assess the level of resistance to chloroquine (CQ) of Plasmodium falciparum in The Gambia in 1995-1996 we measured susceptibility in vivo by quantifying parasitaemia of children with mild malaria on days 4 and 8 after treatment. Pretreatment blood samples were used for susceptibility testing in vitro by the World Health Organization microtest and the prevalence of the tyrosine (tyr)86 allele of the Pfmdr1 gene was assessed by the polymerase chain reaction and restriction fragment length polymorphism analysis. Seven of 42 children (17%) treated with CQ remained parasitaemic on day 4 and required a change of antimalarial treatment. Susceptibility assays in vitro were performed on 50 P. falciparum isolates obtained from eligible children before treatment; 36 (72%) were resistant to CQ (> or = 1.6 mumol/L). The median minimum inhibitory concentration (MIC) of artemether was 3.38 nmol/L (range 0.42-13.51 nmol/L) and the median MIC of dihydroartemisinin was 0.88 nmol/L (range 0.22-14.04 nmol/L). Susceptibility in vitro to CQ and the Pfmdr1 genotype were determined for 31 fresh isolates. The allele was present in 12 of 22 isolates found to be resistant to CQ in vitro, but in none of the 9 isolates which were susceptible (Fisher's exact test, P = 0.005). All P. falciparum isolates with the tyr86 allele were CQ resistant in vitro, but since only half of all resistant isolates contained the allele, additional explanations for CQ resistance are required. PMID- 9373653 TI - Alleles of the Plasmodium falciparum Pfmdr1 gene appear not to be associated with chloroquine resistance in India. PMID- 9373654 TI - Antifolate drug resistance and point mutations in Plasmodium falciparum in Kenya. AB - Due to increased chloroquine resistance, the antifolate/sulpha drug combinations are becoming increasingly important in the chemotherapy of falciparum malaria. However, point mutations in the dihydrofolate reductase gene lead to resistance to the antifolate drugs. We therefore investigated the prevalence of the 6 reported point mutations in this gene among field isolates of Plasmodium falciparum from Kenya, to determine if the mutations correlated with resistance to pyrimethamine and the biguanides cycloguanil and chlorcycloguanil. We used a mutation-specific polymerase chain reaction technique to test for these reported mutations in 21 Kenyan isolates and 4 reference lines. We also amplified and directly sequenced the dihydrofolate reductase coding sequence from these parasites to confirm the results and test for other possible mutations. Of the reported mutations, we found S108N, which is the central mutation of pyrimethamine resistance, and mutations N51I and C59R, which modulate the levels of resistance and may confer decreases in response to cycloguanil that are folate and p-aminobenzoic acid dependent. No isolate possessed the paired point mutations S108T and A16V, or I164L and S108N, which have been associated with cycloguanil resistance in previous studies. These results provided supportive evidence for the combined use of a cycloguanil-class drug (e.g., chlorproguanil) and a sulpha drug (e.g., dapsone) against P.falciparum malaria in Kenya. PMID- 9373655 TI - DHFR gene point mutation as a predictor of Plasmodium falciparum resistance to cycloguanil in malaria cases from Africa imported to France. PMID- 9373656 TI - Comparison of 3, 5 and 7 days' treatment with Quinimax for falciparum malaria in Guinea-Bissau. AB - For treatment of malaria, the World Health Organization recommends 10 mg of quinine per kg body-weight 3 times a day for at least 7 d. In Guinea-Bissau, as in several other African countries, a 3 d treatment regimen (10 mg/kg twice daily) is currently used. We therefore compared the 3 d treatment period with periods of 5 and 7 d. A total of 145 children with clinical malaria due to monoinfection with Plasmodium falciparum, with > or = 20 parasites per 200 leucocytes, were treated with intramuscular Quinimax 10 mg per kg body-weight twice daily for 3, 5 or 7 d. The children were then examined once weekly for 4 weeks. Following the 3 d treatment regimen, 34 of 43 children (79%) had parasitaemia on day 28 or before; following the 5 d treatment regimen, 36 of 40 children (90%) did so; and following the 7 d treatment regimen, 7 of 62 children (11%) were parasitaemic at that time. This study thus suggests that the currently recommended 3 d Quinimax treatment regimen in Guinea-Bissau for moderate and severe malaria is not effective. PMID- 9373657 TI - Severe and complicated malaria treated with artemisinin, artesunate or artemether in Viet Nam. AB - One hundred and seventy five Vietnamese adults with severe and complicated malaria admitted to a rural district hospital were entered into an open randomized comparative study to compare 4 treatment regimens based on artemisinin and its derivatives. The median time of defervescence was 48 h (95% confident interval [CI] 38-58 h) in those given intramuscular (i.m.) artemether, 42 h (95% CI 36-48 h) in those given artemisinin suppositories, 36 h (95% CI 30-42 h) in those receiving artesunate (i.m.) and 30 h (95% CI 18-42 h) in those receiving intravenous artesunate (P = 0.13). The respective median parasite clearance times were 30 h (95% CI 26-34 h), 30 h (95% CI 24-36 h), 24 h (95% CI 15-33 h), and 24 h (95% CI 15-33 h) (P = 0.30); the median times for recovery of consciousness were 47 h (95% CI 31-63 h), 24 h (95% CI 18-30 h), 30 h (95% CI 18-42 h), and 24 h (95% CI 4-44 h) (P = 0.18); and the mortality rates were 11.1%, 17.6%, 10.2% and 16.6%, respectively (P = 0.64). There was no significant difference in efficacy between the 4 treatments. PMID- 9373660 TI - Alveolar echinococcosis: Em2plus-ELISA and Em18-western blots for follow-up after treatment with albendazole. AB - Eleven cases of alveolar echinococcosis (Echinococcus multilocularis infection) with non-resectable lesions but treated with albendazole for 17 to 69 months were followed-up clinically and serologically for 4.5-11.5 years. Based on the clinical outcome and computerized tomography (CT) scanning, they were divided into 4 groups of 2 cured cases, 5 stabilized cases, 3 cases with recurrences, and one treatment failure. Forty-seven sequentially collected sera from the 11 cases were analysed by sequential enzyme-linked immunosorbent assay (ELISA) using Em2plus antigen (Em2plus-ELISA) and Western blotting to detect antibody response against Em18 (Em18-Western blots). The antibody levels in one of the cured and 2 of the stabilized cases fell below the cut-off level in the Em2plus-ELISA 4.5-6 years after effective treatment, whereas all other cases, including 2 of those with recurrences, showed large reductions initially but increased again during the follow-up period. Em18-Western blots of the 2 cured cases and 2 of the stabilized cases became negative. IgG subclasses with responses against Em18 which fell to zero included IgG1 (2), IgG3 (one) and IgG4 (one). All other cases showed no decrease in antibody response against Em18. There were, in general, reasonably reliable correlations between the success or failure of chemotherapy and antibody responses by Em2plus-ELISA and Em18-Western blots. These results suggest that both Em2plus-ELISA and Em18-Western blot are potentially useful in evaluating and predicting the efficacy of chemotherapy. PMID- 9373658 TI - Plasmodium falciparum: sensitivity in vivo to chloroquine, pyrimethamine/sulfadoxine and mefloquine in western Myanmar. AB - In Rakhine State, on the western border of Myanmar, the efficacy of chloroquine (CQ) and pyrimethamine/ sulfadoxine (PS), the current treatments for uncomplicated Plasmodium falciparum malaria in this area, was evaluated in an open comparative study of 289 patients, stratified prospectively into 3 age groups. Chloroquine treatment was associated with more rapid clinical recovery (P = 0.03), but the overall cure rates were worse than for PS treatment; failure to clear parasitaemia or recrudescence within 14 d occurred in 72% (102/141) of cases treated with CQ compared to 47% (69/148) of those who received PS (P < 0.0001, adjusted for age). Failure rates at day 28 increased to 82% (116/141) in the CQ group and 67% (99/148) in the PS group (P = 0.003). The risk of treatment failure was significantly higher in children under 15 years old than in adults for both CQ (relative risk [RR] = 2.6; 95% confidence interval [95% CI] 1.3-5.2) and PS (RR = 2.2; 95% CI 1.4-3.3). Mefloquine (15 mg base/kg) proved to be highly effective as a treatment for CQ and PS resistant P. falciparum; only 2 of 75 patients (3%) had early treatment failures (< or = day 7), and the overall failure rate by day 42 was 7%. There is a very high level of chloroquine and PS resistance in P.falciparum on the western border of Myanmar, but mefloquine was effective in the area. PMID- 9373659 TI - Non-ulcerative cutaneous leishmaniasis in Honduras fails to respond to topical paromomycin. AB - A double-'blind', placebo-controlled trial of topical therapy with 15% paromomycin (aminosidine) and 10% urea in white paraffin was carried out on 53 patients with non-ulcerating cutaneous leishmaniasis in Honduras. Although the treatment was not effective, several unexpected findings emerged from the trial. Leishmania mexicana was found to be the cause of many of the skin lesions in one of the 2 study sites. These lesions were clinically indistinguishable from those caused by L. chagasi, the aetiologic agent previously found for this form of leishmaniasis. This is the first documented report of L. mexicana in Honduras. PMID- 9373661 TI - Semi-quantitative measurement of Plasmodium falciparum antigen PfHRP2 in blood and plasma. AB - Plasmodium falciparum histidine rich protein 2 (PfHRP2) antigen was measured semi quantitatively in whole blood, plasma, and supernatants and red blood cells of cultures in vitro using the dipstick ParaSight-F test and also by a quantitative antigen-capture enzyme-linked immunosorbent assay (ELISA). In vitro, PfHRP2 was secreted mainly during the second half of the asexual cycle with a marked rise during schizont development and rupture. The total PfHRP2 secreted before schizogony corresponded to approximately 4% of that contained in the red blood cells. In samples from 55 patients with acute falciparum malaria, the level of detection by ELISA corresponded to parasitaemias of 100/microL for whole blood and 1600/microL for separated plasma. Whole blood PfHRP2 levels were correlated significantly with admission parasitaemia (r = 0.76, P < 0.0001) and the stage of parasite development (r = 0.43, P < 0.01). Although whole blood PfHRP2 concentrations were higher in severe malaria, plasma concentrations of PfHRP2 were considerably higher in severe malaria (median titre 1:320, range zero to 1:1280) than in uncomplicated malaria (median titre 1:5, range zero to 1:80; P < 0.0001). The ratio of whole blood to plasma PfHRP2 was lower in severe than in uncomplicated malaria (median 4, range 0.25 to 256, versus 64, range 4 to 1280; P < 0.0001). With plasma samples the intensity of colour change on the dipstick correlated well with more precise measurement of optical density in the ELISA (r = 0.88, P < 0.0001). These results suggest that measurement of PfHRP2 in plasma could provide an alternative approach to the assessment of the parasite biomass, and thus prognosis, in severe malaria, and that this could be done simply by using the currently available dipsticks. PMID- 9373662 TI - Immunoblot evaluation of the species-specificity of Em18 and Em16 antigens for serodiagnosis of human alveolar echinococcosis. AB - An immunoblot study to confirm the species-specificity of the diagnostic antigens Em18 and Em16 of Echinococcus multilocularis protoscolex extract showed that both antigens cross-reacted with sera from cystic echinococcosis (CE) patients. The 18 kDa component was detectable by 75% of the sera from active alveolar echinococcosis (AE) patients, while only 31% detected Em16. Western blot analysis also showed that AE sera recognized a band in the 18 kDa region of E. granulosus protoscolex extract, which was different from the 16/17 kDa subunit of antigen B. The results suggested that Em18 antigen is present in E. granulosus as well as E. multilocularis, and that some CE patients may have serum antibody against this antigen. PMID- 9373663 TI - Ronald Ross (1857-1932): 100 years since the demonstration of mosquito transmission of Plasmodium spp--on 20 August 1897. PMID- 9373664 TI - Hepatitis B and C viruses and hepatocellular carcinoma. PMID- 9373665 TI - Temporal properties of marmoset lateral geniculate cells. AB - We measured the temporal modulation transfer functions (TMTFs) of cells in the marmoset lateral geniculate nucleus (LGN) at three different luminance levels, and described the responses with a linear model. It was found that qualitatively there are many similarities with the temporal response properties of macaque and marmoset retinal ganglion cells. M-cells displayed stronger attenuation at lower temporal frequencies, and showed more nonlinearities (such as saturation and a contrast gain control) than P-cells. We therefore propose that the temporal properties of the visual system of New and Old World monkeys are similar at least up to the LGN. However, there are some quantitative differences, indicating that response alterations take place at the stage of synaptic transmission in the LGN. The most important are an attenuation of the responses to higher temporal frequencies and the smaller differences between parvo- and magnocellular cell responsivities. Cell responses to square-wave modulation were also measured and compared with predictions from a linear systems analysis. The linear systems analysis gave reasonable predicted responses to square-wave modulation, but these predictions were poor than those for retinal ganglion cells, indicating that additional nonlinearities are introduced at the synaptic transition in the LGN. PMID- 9373666 TI - Flicker parameters are different for suppression of myopia and hyperopia. AB - Axial eye growth rates in the chicken are controlled by local retinal image processing circuits. These circuits quantify the loss of contrast for different spatial frequencies and promote axial eye growth rates in correlation with the amount of retinal image degradation ("deprivation myopia"). They also distinguish whether the plane of focus lies in front of or behind the retina. How the sign of defocus is detected still remains unclear. Cues from chromatic aberration are not important. In an attempt to isolate retinal circuits controlling the development of myopia or hyperopia, young chickens were raised in flickering light of different frequencies (12 and 6 Hz) and duty cycles (4-75%) produced by rotating chopper disks. The effects of flickering light on refractive errors and change in axial growth rates induced by translucent occluders or defocusing lenses were measured by infrared retinoscopy and A-scan ultrasound, respectively. Retinal electrical activity was evaluated by flicker ERG after matching flicker parameters and stimulation brightness at retinal surface. Changes in retinal and vitreal dopamine content caused by flicker in occluded and normal eyes were determined by HPLC-ECD. Strikingly, suppression of myopia occurred for similar flicker parameters, whether induced by translucent occluders ("deprivation") or negative lenses ("defocus"). The degree to which myopia was suppressed was correlated with the duration of flicker dark phase and with the ERG amplitude. In contrast, suppression of hyperopia did not correlate with these parameters. We conclude that two different retinal circuits with different temporal characteristics are involved in the processing of hyperopic defocus/deprivation and of myopic defocus, the first one dependent on flicker ERG amplitude. However, we did not find any correlation between the rate of dopamine release and the degree of inhibition of deprivation myopia in flickering light. PMID- 9373667 TI - The development of stereoacuity in infant rhesus monkeys. AB - The emergence of stereopsis at 3-4 months postnatal in human infants is striking and has led to speculation that its rapid onset and subsequent development must be due to a dramatic reorganization of the brain. Stereopsis has never been measured in infant monkeys, but previous studies have demonstrated that many other visual functions develop four times faster in infant monkeys than in humans. We made longitudinal assessments of stereoacuity in 11 infant rhesus monkeys. A forced-choice preferential-looking technique was used to present random-dot stereograms during testing. By 8 weeks after birth, all of the monkeys were responding to at least coarse levels of disparity (1760" [seconds]), and by 13 weeks of age, all were responding to the relatively fine level of 88" disparity. Age of onset for stereopsis in monkeys was at about one-quarter the age when it occurs in humans, as expected. However, subsequent development proceeded at a similar absolute rate in monkeys and humans. The findings are discussed relative to the neural mechanisms which might be responsible for the differing rates of development. PMID- 9373668 TI - Dual multiple-scale processing for motion in the human visual system. AB - A number of psychophysical and physiological studies have suggested that first- and second-order motion signals are processed, at least initially, by independent pathways, and that the two pathways both consist of multiple motion-detecting channels that are each narrowly tuned to a different spatial scale (spatial frequency). However, the precise number and nature of the mechanisms that subserve first- and second-order motion perception in human vision remain both controversial and speculative. We sought to clarify this issue by conducting selective adaptation experiments, in which modulation-depth thresholds for identifying the direction of stimulus motion of first-order (luminance-defined) and second-order (contrast-defined) drifting gratings were measured both prior to and following adaptation to motion. The drift direction, spatial frequency and stimulus type (either first- or second-order) of the adaptation and test stimuli were systematically manipulated. When the adaptation and test stimuli were either both first-order gratings or both second-order gratings, robust elevations of direction-identification thresholds were found and, importantly, these aftereffects exhibited both direction-selectivity and spatial-frequency selectivity. Cross-over-adaptation effects between first- and second-order gratings were also sometimes observed, but were very weak and not spatial frequency selective. These findings give direct support for the existence of multiple-scale processing for first- and second-order motion in the human visual system and provide additional evidence that the two varieties of motion are initially processed by independent pathways. PMID- 9373669 TI - Infant color vision: temporal contrast sensitivity functions for chromatic (red/green) stimuli in 3-month-olds. AB - In order to investigate the development of temporal contrast sensitivity functions (tCSFs) for chromatic (red/green) stimuli, we obtained chromatic contrast thresholds from 3-month-old infants and adults using behavioral techniques. Stimuli were moving or counterphase-reversing sinusoidal gratings of 0.25 c/deg. Five temporal frequencies were used: 0.7, 2.1, 5.6, 11 and 17 Hz (corresponding speeds = 2.8, 8.4, 22, 44 and 67 deg/sec). In order to compare chromatic results with those obtained under luminance-defined conditions, luminance tCSFs were also obtained from adults, and previously obtained infant luminance tCSFs were used (from Dobkins & Teller, 1996a). In accordance with previous studies, adults exhibited bandpass luminance tCSFs with peaks near 5 Hz and lowpass chromatic tCSFs that declined rapidly at temporal frequencies greater than 2 Hz, and the two curves crossed one another near 4 Hz. By contrast, infants exhibited bandpass rather than lowpass chromatic tCSFs with peaks near 5 Hz. These chromatic curves were quite similar in peak frequency and general shape to previously obtained infant tCSFs for luminance stimuli. Moreover, both chromatic and luminance tCSFs in infants were found to be quite similar in peak and shape to luminance tCSFs observed in adults. These findings point to the possibility that, for 3-month-old infants, both chromatic and luminance stimuli are detected by the same underlying mechanism under these conditions. We propose that such a mechanism is probably a physiological pathway dominated by magnocellular input. Earlier studies of infant color vision are discussed in this context. PMID- 9373670 TI - Motion interference: perturbing perceived direction. AB - The minimum stimulus necessary to define motion is a change in position from one location to another in time, but past studies have provided evidence that the human motion system integrates motion over more than two positions. In this study we demonstrate strong sequential interactions affecting perceived direction in apparent-motion sequences; a perturbing dot can bias the perceived direction of motion between two test dots to which it is relatively close in space (up to 100 min arc) and time (up to 300 msec). These sequential interactions suggest a motion mechanism sensitive to the spatial characteristics of motion trajectories; the interactions are greatest for evenly spaced targets positioned along a single axis. The implications for motion-detection models and models based on attention as a mechanism to create apparent motion are discussed. PMID- 9373671 TI - Human stereo matching is not restricted to epipolar lines. AB - Computational approaches to stereo matching have often taken advantage of a geometric constraint which states that matching elements in the left and right eye images will always fall on "epipolar lines". The use of this epipolar constraint reduces the search space from two dimensions to one, producing a tremendous saving in the computation time required to find the matching solution. Use of this constraint requires a precise knowledge of the relative horizontal, vertical and torsional positions of the two eyes, however, and this information may be unavailable in many situations. Experiments with dynamic random element stereograms reveal that human stereopsis can detect and identify the depth of matches over a range of both vertical and horizontal disparity. Observers were able to make accurate near/far depth discriminations when vertical disparity was as large as 45 arcmin, and were able to detect the presence of correlation over a slightly larger range. Thus, human binocular matching sensitivity is not strictly constrained to epipolar lines. PMID- 9373672 TI - The aperture problem in stereopsis. AB - Stereoacuity was determined for gratings and gabor patches as their orientation was varied. Acuity was constant for 1 c/deg and 2 c/deg gratings over the range 0 80 deg when it was expressed as positional shift at right angles to the grating orientation. The same was true of an 8 c/deg elongated gabor patch. However, the threshold disparity at right angles to the major axis of an oriented gaussian patch rose as it was tilted away from the vertical. Also, thresholds for a circularly symmetrical gaussian patch rose steeply with the angle of the disparity away from the horizontal. Disparities of the centroids of 4 c/deg gabor patches could be detected equally well at angles of 0 and 70 deg, independently of the angle of the carrier grating. The data indicate a variety of rules for stereoscopic matching. Large-field gratings are matched by detecting orthogonal phase shifts, or alternatively phase shifts along the horizontal axis. Smaller patches of grating are matched by their centroids, independently of their angle. Small gaussian patches are difficult to match in any direction other than along the horizontal axis. The difference between gaussian patches and 4 c/deg gabor patches with the same envelope argues against the involvement of a second-order rectifying non-linearity preceding matching. PMID- 9373673 TI - The spatial relationship between scanning saccades and express saccades. AB - When monkeys interrupt their saccadic scanning of a visual scene to look at a suddenly appearing target, saccades to the target are made after an "express" latency or after a longer "regular" latency. The purpose of this study was to analyze the spatial patterns of scanning, express, and regular saccades. Scanning patterns were spatially biased. Express saccade patterns were biased, too, and were directly correlated with scanning patterns. Regular saccade patterns were more uniform and were not directly correlated with scanning patterns. Express saccades, but not regular saccades, seemed to be facilitated by preparation to scan. This study contributes to a general understanding of how monkeys examine scenes containing both unchanging and suddenly appearing stimuli. PMID- 9373674 TI - Impairment of the binocular coordination of saccades in strabismus. AB - To examine the link between binocular vision and binocular coordination of saccades we studied subjects with convergent strabismus since childhood with mild or no amblyopia: three subjects had small squint (< 10 prism D) and preserved peripheral binocular visual function with gross stereopsis; four subjects had larger squint (18-35 prism D) and no detectable stereopsis. A standard paradigm was used to elicit horizontal saccades; binocular recordings were made with the IRIS device. For subjects with small strabismus, saccades were disconjugate (unequal between the two eyes) typically by 1 deg. Subjects with larger strabismus exhibited even larger and more variable disconjugacy (typically 1.8 deg). Post-saccadic eye drift was consistently divergent in subjects with small strabismus and tended to reduce the convergent squint angle. In contrast, in subjects with large strabismus drift was convergent. The impairment of the binocular control of saccades is attributed to the deficiency of disconjugate oculomotor adaptive capabilities necessary to compensate for the natural asymmetries or changes in the two oculomotor plants; such deficiency would be more severe in subjects with large strabismus who have neither central nor peripheral binocular vision. PMID- 9373675 TI - Deficiency of adaptive control of the binocular coordination of saccades in strabismus. AB - Disconjugate (different in the two eyes) oculomotor adaptation is driven by the need to maintain binocular vision. Since binocular vision is deficient in strabismus, we wondered whether oculomotor disconjugate adaptive capabilities are deficient in such subjects. We studied eight adult subjects with constant, long standing convergent strabismus of variable angles (4-30 prism D). No subject had severe amblyopia. Binocular vision was evaluated with stereoacuity tests. Two subjects had peripheral binocular vision and gross stereopsis; two other subjects had abnormal retinal correspondence and abnormal or pseudo gross stereopsis. In the other subjects binocular vision and stereopsis were absent. To stimulate disconjugate changes of saccades, subjects viewed for 20 min an image that was magnified in one eye (aniseikonia). Subjects with residual peripheral binocular vision and even subjects with pseudo or abnormal binocular vision showed disconjugate changes of the binocular coordination of their saccades; these changes reduced the disparity resulting from the aniseikonia. In contrast, for subjects without binocular vision the changes were not correlated with the disparity induced by the aniseikonia. Rather, these changes served to improve fixation of one or the other eye individually. PMID- 9373676 TI - Analysis of the effect of pattern adaptation on pattern pedestal effects: a two process model. AB - Pattern contrast thresholds for vertical Gabor patterns were measured on pattern pedestals that were vertical or horizontal. Contrast of the pedestal was varied to measure the function relating target contrast threshold to pedestal contrast (TvC function). TvC functions were measured without an adaptor and after adaptation to vertical, horizontal and plaid patterns. For a pedestal with the same orientation as the target, the vertical and plaid adapters increased thresholds at low pedestal contrasts, but not high. For the pedestal orthogonal to the target, the same two adaptors increased thresholds over the whole range of pedestal contrasts. These asymmetric effects are described by a model of adaptation and masking derived from a model of masking (Foley, 1994a) by allowing two parameters to vary with the adapt state; one of them is an additive parameter in the denominator of the response function, which can be interpreted as adaptor produced divisive inhibition that persists after adaptor offset; the other is the sensitivity to pedestal-produced divisive inhibition, which is changed by adaptation for the pedestal orthogonal to the target. Other models do not account for both effects. PMID- 9373678 TI - Quantitative perimetry under binocular viewing conditions in microstrabismus. AB - In order to elucidate the type, size and depth of suppression scotomata in microstrabismus and small angle convergent strabismus, we performed binocular static perimetry in 14 subjects with strabismus and four normal observers. The strabismic cases had an objective angle of convergent squint between 1 and 8 deg, visual acuity between 0.1 and 1.25, and limited stereopsis. During testing the subjects fused pictures on two Friedmann visual field analyzers. Right and left eyes were studied separately under both monocular and binocular viewing conditions. In five strabismics a suppression scotoma was found in the squinting eye, with a diameter of 5-30 deg and a depth ranging from 4 to 14 dB. No suppression scotomata could be detected in the nine other subjects nor in the four normal observers. In conclusion, only 36% of subjects with strabismus were found to have a suppression scotoma. These scotomata were centered around the fixation point of the squinting eye, in some cases also encompassing the foveal area, and varying in depth and size. PMID- 9373677 TI - Biometric investigation of changes in the anterior eye segment during accommodation. AB - Non-invasive biometry of the anterior structures of the human eye can be performed with unprecedented precision of 8-10 microns and a resolution of approximately 9 microns by partial coherence interferometry, which has the potential to assess the effect of cycloplegia on the ocular components of the anterior eye segment, to further improve the precision to 1-2 microns by the use of these agents and to quantify the amount of residual accommodations in different states of cycloplegia. In addition, the anterior chamber depth, the thickness of the crystalline lens, their changes during accommodation, as well as the movement of the anterior and posterior lens pole during accommodation can be quantified objectively and accurately to investigate the mechanism of accommodation. PMID- 9373679 TI - A quantitative estimate of flash-induced Ca(2+)- and Na(+)-influx and Na+/Ca(2+) exchange in blowfly Calliphora photoreceptors. AB - The flash-induced Ca(2+)- and Na(+)-influx and Na+/Ca(2+)-exchange activity in blowfly Calliphora photoreceptors were investigated. The change in membrane potential, induced by a bright flash, was intracellularly measured in vivo. Based on a biophysical photoreceptor model, the Na(+)- and Ca(2+)-currents and concentration changes were determined from the first transient depolarization phase of the photoreceptor response. The activity of Na+/Ca(2+)-exchange was determined from the after depolarization phase. It appeared that the Na(+)-influx by Na+/Ca(2+)-exchange is about twice that through light-activated channels, suggesting a substantial contribution of Na+/Ca(2+)-exchange to Na(+)-regulation. PMID- 9373680 TI - Piscine (Sparus aurata) alpha subunit of the G-protein transducin is homologous to mammalian cone and rod transducin. AB - A novel cDNA encoding alpha subunit of the GTP-binding protein, transducin, has been cloned from a marine fish, Sparus aurata. The cDNA contains an open reading frame of 1050 nt (encoding 350 amino acid residues). A high degree of identity was found with known mammalian transducin proteins of cones (Gt2 alpha) or rods (Gt1 alpha): human Gt2 alpha (80.2%), bovine Gt2 alpha (79.3%), mouse Tt1 alpha (78.2%), mouse Gt2 alpha (78%) and bovine Gt1 alpha (77.9%). Northern blot analysis of different tissues revealed a transcript of about 2.5 kb, which is expressed only in the fish eye and not in other tissues from adult fish, supporting its identification as transducin. Ontogeny of transducin mRNA expression during early development of Sparus aurata, determined by Northern blot analysis, showed very low levels in larvae 3 days after hatching but not earlier. Levels increased 3- and 6-fold on days 4 and 6 (respectively) compared with those on day 3 and remained essentially unchanged thereafter, until day 21 after hatching (the last day studied). Our results suggest that in fish only one alpha subunit of transducin is found, which shows similar identity with cone and rod alpha subunits of mammals. PMID- 9373682 TI - Motion blur and motion sharpening in the human visual system. AB - The effect of motion sharpening upon blur discrimination thresholds was examined for a range of speeds and blur widths. Blur discrimination thresholds were measured for drifting edges whose blur was either physically or perceptually constant. Under conditions where edges were kept at a constant physical blur width, discrimination thresholds rose as a function of speed as previously reported. However, when the perceived blur of edges was held constant, discrimination performance was more-or-less constant for speeds up to at least 6.3 deg sec-1. The results indicate that the deterioration of blur discrimination performance with speed may be due to motion sharpening and not motion blur as has previously been suggested. The results are discussed in terms of a scheme whereby a non-linearity in motion processing serves to sharpen moving edges, whilst the finite integration time of the system tends to smear them. PMID- 9373681 TI - Serotonin elevates the c-wave of the electroretinogram of the rabbit eye by increasing the transepithelial potential. AB - The influence of serotonin (5-hydroxytryptamine, 5-HT) and serotonin analogues on the direct current electroretinogram (d.c. ERG) and the standing potential of the albino rabbit eye (SP) was studied. After unilateral vitrectomy, corneal recordings were obtained during simultaneous intravitreal perfusion with a control solution alternating with 5-HT at concentrations of 25, 120 and 200 microM. The c-wave increased at 25 and 120 microM when changing from control solution to test solution (P < 0.05) but did not decrease significantly when changing back to control solution (P > 0.05). The c-wave was reversibly elevated at 200 microM (PHS-5-HT, P < 0.01; 5-HT-PHS, P < 0.05). To analyse further the influence on the c-wave, in vivo intraretinal microelectrode recordings were obtained during intravitreal perfusion with 5-HT. The transepithelial potential (TEP) increased (P < 0.01), while the slow PIII was not significantly affected (P > 0.05). The serotonin receptor agonists 1-(2,5-dimethoxy-4-iodophenyl)-2 aminopropane, 5-methoxytryptamine, alpha-methyl-5-hydroxytryptamine and 2-methyl 5-hydroxytryptamine, caused a significant reversible elevation of the c-wave, whereas 5-carboxyamidotryptamine did not. Tropisetron did not block the serotonin effect and LY53857 had an effect of its own on the c-wave. The results seem to indicate that the influence of serotonin on the c-wave is mainly due to an effect on the retinal pigment epithelium (RPE) and that more than one type of serotonin receptor may be involved. PMID- 9373683 TI - Accommodation without feedback suggests directional signals specify ocular focus. AB - Accommodation was monitored continuously under open-loop conditions while subjects viewed a sinusoidally oscillating sine-wave grating (0.2 Hz; +/- 1 D; 2.7 c/d; 0.56 contrast) in a Badal optometer. The target was illuminated by monochromatic light (590 nm) or white light (3000 K) with longitudinal chromatic aberration (LCA) normal, doubled, neutralized and reversed. Subjects (12) accommodated well in white light with LCA normal and doubled (mean gains = 0.85 and 0.94), gain was reduced in the neutralized condition (0.54), in monochromatic light (0.43), and especially when LCA was reversed (0.30). The results suggest that accommodation responds to changes in the relative contrast of spectral components of the retinal image and perhaps to the vergence of light. PMID- 9373684 TI - Moving vernier in amblyopic and peripheral vision: greater tolerance to motion blur. AB - The purpose of this study was to examine the hypothesis that higher stimulus velocities could be tolerated in amblyopic and normal peripheral vision. The basis for this hypothesis is that a shift in the spatial scale of processing appears to account for the degradation in vernier acuity for moving stimuli in normal vision, and, to a large degree for the degradation in vernier acuity for stationary stimuli in amblyopic and peripheral vision. Vernier thresholds were determined using a pair of long abutting lines, for velocities ranging between 0 and 8 deg/sec. Comparisons were made between non-amblyopic and amblyopic eyes in two amblyopic observers, and between central and peripheral (5 and 10 deg) vision in two normal observers. We analyzed our threshold vs velocity data using an equivalent noise analysis, and defined the knee of the function, the point at which vernier threshold is elevated by a factor of square root of 2, as the "critical velocity" beyond which image motion degrades vernier acuity. Critical velocities were found to be higher in amblyopic than in nonamblyopic eyes; and higher in peripheral than central vision. Our results are consistent with the predictions from the shift in spatial scale notion--that higher velocity of image motion can be tolerated because of the shift in sensitivity toward lower spatial frequency filter mechanisms in amblyopic and normal peripheral vision. PMID- 9373685 TI - Cortical components of the Westheimer function. AB - The Westheimer function in human cone vision was measured in normal observers under dichoptic conditions and in observers with naturally acquired amblyopia. Results show interocular transfer of both desensitization and sensitization under either "sustained" or "transient" stimulus conditions if binocular rivalry is eliminated. The spatial sensitization branches of the amblyopic functions are considerably broadened as compared with those of the non-amblyopic function. Our results are consistent with cortical components for the Westheimer function which probably reflect the behavior of cortical spatial filters. PMID- 9373686 TI - Interaction between sub- and supra-Nyquist spatial frequencies in peripheral vision. AB - In peripheral vision, high-frequency gratings beyond the Nyquist limit are visible as aliased patterns but, as shown previously, their visibility can be masked by superimposed sub-Nyquist gratings. Is the converse also true? Can supra Nyquist gratings affect the detectability of sub-Nyquist gratings? In this study, we investigated the masking effect of high contrast, supra-Nyquist components of a compound grating on the contrast detection of sub-Nyquist components by employing a temporal three-alternative, forced-choice (3AFC) masking paradigm. We found that high-frequency, aliased gratings with contrast just 2 or 3 times above threshold can have a powerful masking effect on low-frequency, resolved gratings in peripheral vision. This result was surprising because prior results from sub Nyquist masking studies in the fovea and the periphery have indicated that masking occurs only when the mask contrast is at least 5 times greater than threshold. Strong masking by supra-Nyquist gratings that are only just visible may be accounted for by an irregular sampling model in which the alias of the mask is distributed over a band of frequencies in the sub-Nyquist range. Furthermore, if undersampling is the explanation for the results of this study, then masking must occur after spatial sampling. PMID- 9373687 TI - The interaction between stereoscopic and luminance motion. AB - An interaction in apparent motion between perceived three-dimensional forms defined by stereopsis and local luminous elements is reported. Vertical stripes of cyclopean square gratings were simulated by random-dot stereograms. Alternation of two-frame stereograms whose phases differed by 90 deg caused two kinds of percepts, planes' motion in depth (first-order stereoscopic motion, first-order SM) or lateral motion of gratings (higher-order stereoscopic motion, higher-order SM). Experiment 1 explored the conditions under which higher-order SM frequently arose, as opposed to local luminance-based in-depth motion (first order SM). The results show that, when the spatial arrangements of two-frame random dots were correlated, higher-order SM dominated for long ISI conditions (ISI > 73 msec). When they were uncorrelated, higher-order SM dominated even under zero ISI conditions. Subjects reported that, when higher-order SM was seen, dots were attached to the surfaces of the moving cyclopean figure (motion capture). Experiment 2 tested which factor caused the domination of higher-order SM under uncorrelated conditions in Experiment 1, the larger distance of dot jump or the varied directions of the dots' motion. The results show that, when the distance of dot jump is large or when the directions of dots' motion are incoherent, higher-order SM arises more frequently. When local first-order motion signals are weakened by appropriate temporal and spatial conditions or by incoherent motion directions, higher-order SM dominates and it captures the motion of dots. PMID- 9373688 TI - Shape priming in a complex visual search task. AB - Shape priming was studied in four experiments comprising a complex search task in which subjects searched for a target shape presented among three distractors and reported the location of the target. Localization performance improved as a function of the duration of stimulus exposure and prime lead time. The efficiency of shape primes in improving performance decreased when lateral masks were presented near the target. Generally, both preprimes and simultaneous primes improved localization accuracy. With laterally masked stimuli, the preprimes and simultaneous primes were equally effective; when neighboring mask items were absent, the effect of preprimes was more pronounced. The results suggest that different strategies were used in the preprime and in the simultaneous-prime conditions. PMID- 9373689 TI - The transition from DeVries-Rose to Weber's laws: comments on Rovamo, Mustonen and Nasanen (1995) AB - Rovamo et al. [Vision Research (1995), 35, 767-774] measured contrast sensitivity at several frequencies in the fovea and periphery as a function of retinal illuminance, concluding that the critical illuminance for the transition from DeVries-Rose to Weber's laws is proportional to squared frequency at all retinal locations. Yet, inspection of their data clearly reveals that the DeVries-Rose range was hardly ever followed by a Weber range: either no sign of any second range was apparent or the transition was to a qualitatively different range in which sensitivity decreased with increasing illuminance. The validity of their conclusions is questioned, and the status of the "DeVries-Rose to Weber transition" as a description of the relationship between sensitivity and illuminance is discussed in the light of mounting empirical evidence of a decreasing range in this relationship. PMID- 9373690 TI - Offset dynamics of human smooth pursuit eye movements: effects of target presence and subject attention. AB - Subjects made smooth pursuit eye movements with a target moving horizontally at 15 deg/sec. At a specified location the target either: (1) suddenly vanished; or (2) jumped to the fovea with target retinal velocity and feedback becoming 0 (target stabilized at the fovea). In each type of trial, the subjects either: "looked" at the target, "pushed" the target, or "passively" gazed. When the target vanished, eye velocity decreased exponentially with a short time-constant (tau approximately 0.10 sec), regardless of whether the subjects were "looking," "pushing" or "passively" gazing. However, some subjects while "pushing" (using an imaginary target) did generate low velocity smooth movement (1-2.5 deg/sec) late in the offset. When the target was stabilized at the fovea, eye velocity also decreased, but with a relatively long time-constant (tau = 0.4-0.8 sec). The time constant was the same with both "looking," and "pushing", but was shorter for some subjects with "passive" gazing (tau = 0.1-0.5 sec). These findings show that smooth pursuit offset is influenced by the presence of a target, but is relatively independent of attentional mode. All of the pursuit offset responses can be simulated using a model of the pursuit system with target velocity and position inputs, and an internal positive feedback loop enabled by target presence. PMID- 9373691 TI - Gaze-shift dynamics in two kinds of sequential looking tasks. AB - Gaze-shift dynamics of unrestrained seated subjects were examined. The subjects participated in two tasks. In the first task, they tapped sequences of 3-D targets located on a table in front of them. In the second task, they only looked at similar sequences of targets. The purpose of the task (tapping vs only looking) affected the dynamics of gaze-shifts. Gaze and eye-in-head peak velocities were higher and gaze-shift durations were shorter during tapping than during looking-only. We conclude that task variables affect gaze-shift dynamics, altering characteristics of the so-called saccadic "main sequence". PMID- 9373692 TI - Capture and transparency in coarse quantized images. AB - This study examines the effect of coarse quantization (blocking) on image recognition, and explores possible mechanisms. Thresholds for noise corruption showed that coarse quantization reduces drastically the recognizability of both faces and letters, well beyond the levels expected by equivalent blurring. Phase shifting the spurious high frequencies introduced by the blocking (with an operation designed to leave both overall and local contrast unaffected, and feature localization) greatly improved recognizability of both faces and letters. For large phase shifts, the low spatial frequencies appear in transparency behind a grid structure of checks or lines. We also studied a more simple example of blocking, the checkerboard, that can be considered as a coarse quantized diagonal sinusoidal plaid. When one component of the plaid was contrast-inverted, it was seen in transparency against the checkerboard, while the other remained "captured" within the block structure. If the higher harmonics are then phase shifted by pi, the contrast-reversed fundamental becomes captured and the other seen in transparency. Intermediate phase shifts of the higher harmonics cause intermediate effects, which we measured by adjusting the relative contrast of the fundamentals until neither orientation dominated. The contrast match varied considerably with the phase of the higher harmonics, over a range of about 1.5 log units. Simulations with the local energy model predicted qualitatively the results of the recognizability of both faces and letters, and quantitatively the apparent orientation of the modified checkerboard pattern. More generally, the model predicts the conditions under which an image will be "captured" by coarse quantization, or seen in transparency. PMID- 9373693 TI - Motor and perceptual responses to horizontal and vertical eye vibration in humans. AB - Previous studies have shown that low amplitude/high frequency mechanical vibration applied to the human eye muscles results in the illusory movement of a luminous spot fixated in total darkness. The aim of the present study was to investigate whether a vibration-induced motor response also occurs in eye muscles, and to check whether the visual illusions actually result from the proprioceptors being activated by the vibration, or whether they are simply due to the retinal slip induced by the reflex eye movement. The effects of the vibratory stimuli on the inferior rectus (IR) and lateral rectus (LR) muscles were evaluated by recording subjects' eye position changes. When applied to the IR muscle, vibration effectively elicited an upward visual illusion accompanied by a small downward ocular rotation, whereas when applied to the LR muscle, it also induced horizontal visual illusion, which was less frequent and weaker than the vertical one, but no ocular rotation. We concluded that visual illusions of this kind cannot be attributable to the retinal motion of the image of the fixated point. The difference between the vertical and horizontal vibratory motor responses is discussed as regards the particular role that oculo-muscular proprioception may play in the vertical muscles. PMID- 9373694 TI - Simulated cataract does not reduce the benefit of RSVP. AB - Normally sighted younger and older (mean age 71 years) observers read sentences and random lists of words from a rapid serial visual presentation (RSVP) display and a scroll display using their normal vision and through two levels of cataract simulators. Unlike patients with central field loss (CFL), there was no decrease in the benefit of RSVP with reduced vision due to the cataract simulators. However, the usefulness of sentence-level context was reduced as visual acuity was reduced. In addition, older readers did not benefit as much from RSVP as younger readers, and many in the older group were unable to read using the more severe cataract simulators from either display format. From these data we conclude that the benefits of RSVP are not reduced with reduced acuity and contrast sensitivity, and that there are age-related changes in reading rates from dynamic text displays not related to acuity. PMID- 9373695 TI - The role of gastrointestinal factors in alcohol metabolism. AB - Although the liver is the major organ responsible for ethanol metabolism, such metabolism also occurs in the gastrointestinal (GI) tract. However, compared to the liver, GI metabolism of ethanol is quantitatively much lower. Various enzyme systems have been characterized in GI mucosal cells including various isozymes of alcohol dehydrogenase (ADH), cytochrome P450 2E1 (CYP 2E1) and catalase. Gastric ADH activity is one factor by which first pass metabolism (FPM) is influenced and its activity is modulated by genetics, gender, age, drugs and gastric morphology. Another important factor in FPM of ethanol is the speed of gastric emptying. In addition to mucosal ethanol metabolism, ethanol can also be oxidized by many bacterial species in the upper GI tract including oropharynx and stomach as well as in the large intestine. GI metabolism of ethanol may influence systemic bioavailability of ethanol and may lead to local toxicity most likely mediated by acetaldehyde. Such toxicity could be of importance in ethanol-associated carcinogenesis. PMID- 9373696 TI - Nitric oxide is not increased in alcoholic brain. AB - Nitric oxide (NO) metabolites nitrite and nitrate were measured in the cerebrospinal fluid in 12 alcohol-dependent subjects and in 16 healthy controls. The amounts of NO metabolites in alcoholics were not different from those in the controls. The results suggest that NO is not a major factor responsible for brain damage in these patients. PMID- 9373697 TI - Use of a five-compartment closed model to describe the effects of ethanol inhalation on the transport and elimination of injected pyruvate in the rat. AB - A five-compartment closed model was established using the system of differential equations. The completely analytical solution of a five-compartment closed model was found using the Laplace transform. 2-[14C]Pyruvate kinetics were studied in rats without and with inhalation of vaporized ethanol, and were modelled by the five-compartment closed model, i.e. injected site, blood, eliminated 14CO2 in air, eliminated 14C in urine and faeces. The kinetic parameters were estimated using the analytical solution of the five-compartment closed model to fit eliminated 14CO2, and 14C in urine and faeces simultaneously. The compartmental analysis showed that the inhalation of vaporized ethanol can increase 2 [14C]pyruvate trans-membrane, trans-tissue processes and oxidation rate. The model developed is useful for general pharmacokinetic and toxicokinetic analysis as well as for studies on ethanol. PMID- 9373698 TI - Impaired mouse fertilization by low chronic alcohol treatment. AB - Little is known about the effects of low chronic alcohol intake on fertility, particularly in females. Recently, we have shown that chronic 10% (w/v) ethanol treatment affects in-vitro fertilization of mouse female gamete. The aim of this study was to solve questions concerning the lowest dose and duration of ethanol treatment required to alter the fertility of immature and adult female and adult male mouse. Mice were treated with 5% and 2.5% (w/v) ethanol in drinking water for 4 weeks. The in-vitro fertilization rates were significantly decreased with the 5% ethanol when oocytes from prepubertal and pubertal ethanol-treated females were inseminated with spermatozoa from adult control males. The in-vitro fertilization rates were not diminished when oocytes from control females were inseminated with spermatozoa from adult ethanol-treated males. Haploid oocytes were increased when oocytes came from immature females treated with ethanol. The in-vitro fertilization rates were not decreased in adult treated females. The in vivo fertilization rates were not modified when prepubertal ethanol-treated females were mated with adult control males. Fragmented oocytes, in the in-vitro fertilization experiments, were significantly increased when they came from prepubertal and adult treated females inseminated with ethanol-treated males. These results show that there is a threshold of the ethanol dose to produce an effect. Chronic low ethanol ingestion by immature female mice has a deleterious effect on their in-vitro fertilization. Furthermore, acute ethanol ingestion by adult females during the induction of ovulation resulted in high parthenogenetic activation and fragmentation of mouse oocytes. PMID- 9373699 TI - Mortality of treated alcoholics after eight years in relation to short-term outcome. AB - This study concerns the relation between mortality and the short-term outcome of inpatient treatment for alcoholism. A total of 121 patients (87 men, 34 women) were included, of whom 89 were voluntary and 32 compulsorily committed. They had a mean age of 41 +/- 7 (SD) years and attended a 5-week programme at Runnagarden, Orebro, Sweden. Most patients were socially unstable and severely alcohol dependent. Ten months (mean) after discharge, 96% of the patients and their referring social workers were contacted with mail questionnaires. Of these patients, 13% had been totally abstinent and a further 42% improved but had had relapses. After a mean of 8.5 +/- 0.27 years, 27 patients (24%) had died. All abstainers survived, but non-abstainers had nine-fold higher mortality than expected. Non-abstinent improved women tended to survive longer than non-improved women, but among non-abstinent improved men no such tendency was found. In conclusion, a reduction in the frequency and quantity of abusive drinking was not enough to reduce the higher risk of death. Only abstinence seemed to be preventive. PMID- 9373700 TI - Preliminary study of how alcohol consumption during pregnancy affects immune components in breast milk and blood of postpartum women. AB - Human milk has been shown to contain numerous immune components that can potentially protect the infant during the period before its own immune system is completely developed. Alcohol consumption in both experimental animals and humans has been associated with alterations to a number of immune parameters. We have investigated the possibility that alcohol consumption during pregnancy alters certain immune components in day 3 postpartum breast milk and peripheral blood of women. Our study group consisted of 10 alcoholic beverage drinkers (moderate to heavy, most of whom smoked a 1/2-1 pack of cigarettes per day), 15 non drinking/non-smoking controls, and 10 non-drinking/smokers (1/2-1 pack per day) controls. The immune parameters measured in these otherwise healthy women were: (1) percentage and absolute number of the various subsets of leukocytes; (2) percentage of T cells, B cells, T helper and cytotoxic/suppressors subsets, and natural killer cells; (3) levels of the cytokines IL-6, IL-8 and TNF-alpha; (4) levels of IgA in milk and IgG in serum. Milk from the alcohol group contained an elevated amount of IL-8 as compared with milk from non-smoker controls; however, it did not differ statistically from that of the smoker controls. Blood from the alcohol group showed an increased level of IL-8 when compared with that from both smoker and non-smoker controls. The total number of leukocytes in milk was elevated in milk from the alcohol group as compared to both the smoker and non smoker control groups. In the leukocyte component of milk, neutrophils predominate and are responsible for the elevation in total number of cells, as both lymphocyte and macrophage populations did not differ from those of the controls. For lymphocytes, B cells were also increased in blood of the smokers as compared with the alcohol and non-smokers controls. There were no statistical differences in any of the other immune parameters tested among the three groups. The present study found that alcohol consumption during pregnancy could modulate the production of IL-8 and infiltration of certain leukocytes in milk and blood of postpartum women. Some of these alterations were also evident in the smoker controls and thus could not be attributed to alcohol consumption alone. PMID- 9373701 TI - Sex hormones during alcohol withdrawal: a longitudinal study of 29 male alcoholics during detoxification. AB - It is a well-known fact that alcohol affects sex hormone levels in males. Even in the absence of liver dysfunction, there is still a direct toxic effect of ethanol on testosterone synthesis resulting in acutely decreased values. This study is based on 29 male alcoholics without severe signs of liver disease treated on the alcohol detoxification ward at Huddinge hospital in Stockholm, Sweden during 1995. The aim was to study levels of sex hormones in male alcoholics during detoxification with benzodiazepines and after 3 weeks of sobriety. Blood samples were taken three times: one day after admission (day 2) when the patient was sober, at discharge (day 5) and after 3 weeks of sobriety (day 21). Levels of testosterone and sex hormone-binding globulin (SHBG) showed the same pattern during detoxification and follow-up. They were both low, but generally within normal limits, on days 2 and 5, but raised after 3 weeks of sobriety. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) were initially high, but were substantially depressed during detoxification. Levels of FSH recovered after 3 weeks, whereas LH remained at the same level. Most patients exhibited generally low levels of both FSH and LH, however. Levels of oestrone decreased steadily. There were no correlations between levels of sex hormones and the number of milligrams of oxazepam administered to the patients during detoxification either at admission, at discharge or at follow-up. In summary, the endocrinological response to alcohol intake is complex. This study suggests that the duration of endocrinological recovery after drinking is a quite long-lasting process, that different hormones need different times to recover and that the normal glandular pituitary feed-back processes may be partly put out of order. PMID- 9373702 TI - Osteopenia in alcoholics after tibia shaft fractures. AB - A marked reduction of 40-70% in regional bone mineral density (BMD) has been reported after fractures of long bones, and this post-traumatic osteopenia may to some extent persist for several years, perhaps lifelong. In this cross-sectional study, we investigated whether prolonged alcohol abuse had any effect on the degree of post-traumatic osteopenia after isolated tibia shaft fractures, the rationale for such a suspicion being the deranged bone metabolism found in alcoholics. We also wanted to investigate whether dual energy X-ray absorptiometry (DEXA) or quantitative ultrasound technique could detect differences between abusers and non-abusers in post-traumatic bone loss. We measured the BMD in 61 male patients with isolated tibia shaft fractures (1984 94) with the Lunar DPX-L and the Lunar Achilles. Twenty-four of the patients were verified to be high consumers of alcohol. After correction for differences in age and the time elapsed since the fracture event, we found significantly lower (11%; P = 0.017) BMD in the femoral neck of the fractured leg in abusers when utilizing the DEXA technique. No differences between abusers and non-abusers in BMD were detectable when using the ultrasound technique. We found a fair correlation (r = 0.63-0.81) between the DEXA and the ultrasound techniques in regions with spongious bone. Our findings suggest that alcohol abuse has some, albeit a limited, effect on the degree of post-traumatic osteopenia and that ultrasound measurements in the calcaneus are of little use in detecting an increased post traumatic osteopenia in this patient group. PMID- 9373703 TI - Flumazenil in alcohol withdrawal: a double-blind placebo-controlled study. AB - The purpose of the present study was to study gamma-aminobutyric acid (GABA)-A receptor function in alcohol-dependent subjects during withdrawal, using the benzodiazepine antagonist flumazenil. In particular, we wanted to examine the hypotheses that an endogenous inverse agonist ligand at the GABA-A benzodiazepine receptor (GBzR) is active during withdrawal (in which case flumazenil should be anxiolytic), or whether chronic alcohol intake results in a shift in sensitivity of the receptor in the inverse agonist direction (in which case flumazenil should be anxiogenic). Results from 15 alcohol-dependent subjects in a double-blind placebo-controlled cross-over study showed that flumazenil was neither anxiolytic nor anxiogenic, although withdrawal scores were reduced during the course of the study. The fact that flumazenil was not anxiogenic, as it is in panic disorder, suggests that the GBzR is functioning differently in these two clinically similar conditions. PMID- 9373704 TI - Meta-analysis of the effects of alcohol dehydrogenase genotype on alcohol dependence and alcoholic liver disease. AB - The purpose of this paper is to assemble and evaluate existing data on the effect of genetic variation in ADH2 and ADH3 on the risk of alcohol dependence, and on the risk of alcoholic liver disease. Calculations of odds ratios and their confidence limits, and tests for heterogeneity of the results from the available studies, have been performed. It is clear that possession of the ADH2-2 allele decreases the risk of alcohol dependence, but it increases the risk of alcoholic liver disease among alcoholics. ADH3 variation also has significant effects on alcohol dependence, which may be due to linkage to ADH2; the ADH3 effect differs significantly between Asian and European subjects. Therefore ADH genotype has substantial effects on risk of alcohol dependence and alcoholic liver disease, but more work is needed on the generalizability of these findings to non-Asian populations, and on possible mechanisms. PMID- 9373705 TI - Sober-state cortisol as a predictor of drunken violence. AB - Basal cortisol levels were compared in prisoners convicted of violent crimes, in men previously convicted of violent crimes but currently not in prison, in non violent alcoholics, and in randomly selected control males. Most of the violent men were diagnosed with antisocial personality disorder (DSM-III-R 301.70). Morning, afternoon, and evening levels of plasma cortisol were assessed after a minimum alcohol abstinence of 24 h. The imprisoned violent men had significantly lower cortisol levels than the unimprisoned, which may reflect their prolonged alcohol abstinence and/or habituation to chronic stress. The unimprisoned violent men were heavy drinkers and their elevated sober-state cortisol may reflect temporary alcohol withdrawal or acute stress. We suggest that variations in basal cortisol are influenced more by environmental factors than by violent predisposition or antisocial personality disorder. PMID- 9373706 TI - Training general practitioners. PMID- 9373707 TI - Accelerated metabolism of ethanol in patients with burn injury. PMID- 9373708 TI - Detection of autoantibodies to nuclear antigens by EIA and IF techniques. AB - The detection of antibodies to certain nuclear components has considerable importance in the diagnosis and management of patients with autoimmune diseases. In this study, antibodies to nuclear antigens in 250 positive and negative patient specimens were detected by immunofluorescence (IF) and enzyme immunoassay (EIA). Specimens were tested by three different EIA assays for autoantibodies to SS-A, SS-B, Scl-70 Sm, RNP, Jo-1, ENA, Histone, ss-DNA and ds-DNA and one IF assay for Antinuclear Antibodies (ANA). The majority of positive specimens were also confirmed positive by Western Blot. Ninety-seven percent of IF-ANA positive specimens assayed positive by EIA-ENA assay and only 6% of ENA negative specimens tested positive in IF-ANA assay indicating that EIA-ENA assay is as reliable as IF-ANA for screening patient specimens. Forty-five percent of EIA Jo-1 positive specimens showed negative IF-ANA results indicating that IF-ANA assay is not a reliable method for detection of antibodies to Jo-1. This may be due to the fact that specimens with low titer and sera which are positive for a limited number of specific nuclear antigen(s) cannot produce visible or clear fluorescence patterns and therefore are reported negative by IF-ANA. Our data shows that both methods are reliable for screening purposes, however EIA has greater specificity over IF because the presence or absence of antibody to a specific antigen can be better assessed. Overall, due to higher reproducibility, low cost, antigen specificity, and the nature of EIA, we recommend microtiter-based EIA assays for detection of antibodies to nuclear antigens. PMID- 9373709 TI - Image analysis based grading of bladder carcinoma. Comparison of object, texture and graph based methods and their reproducibility. AB - The possibility that computerized image analysis could increase the reproducibility of grading of bladder carcinoma as compared to conventional subjective grading made by pathologists was investigated. Object, texture and graph based analysis were carried out from Feulgen stained histological tissue sections. The object based features were extracted from gray scale images, binary images obtained by thresholding the nuclei and several other images derived through image processing operations. The textural features were based on the spatial gray-tone co-occurrence probability matrices and the graph based features were extracted from the minimum spanning trees connecting all nuclei. The large numbers of extracted features were evaluated in relation to subjective grading and to factors related to prognosis using multivariate statistical methods and multilayer backpropagation neural networks. All the methods were originally developed and tested on material from one patient and then tested for reproducibility on entirely different patient material. The results indicate reasonably good reproducibility for the best sets of features. In addition, image analysis based grading showed almost identical correlation to mitotic density and expression of p53 protein as subjective grading. It should thus be possible to use this kind of image analysis as a prognostic tool for bladder carcinoma. PMID- 9373710 TI - Groping for quantitative digital 3-D image analysis: an approach to quantitative fluorescence in situ hybridization in thick tissue sections of prostate carcinoma. AB - In molecular pathology numerical chromosome aberrations have been found to be decisive for the prognosis of malignancy in tumours. The existence of such aberrations can be detected by interphase fluorescence in situ hybridization (FISH). The gain or loss of certain base sequences in the desoxyribonucleic acid (DNA) can be estimated by counting the number of FISH signals per cell nucleus. The quantitative evaluation of such events is a necessary condition for a prospective use in diagnostic pathology. To avoid occlusions of signals, the cell nucleus has to be analyzed in three dimensions. Confocal laser scanning microscopy is the means to obtain series of optical thin sections from fluorescence stained or marked material to fulfill the conditions mentioned above. A graphical user interface (GUI) to a software package for display, inspection, count and (semi-)automatic analysis of 3-D images for pathologists is outlined including the underlying methods of 3-D image interaction and segmentation developed. The preparative methods are briefly described. Main emphasis is given to the methodical questions of computer-aided analysis of large 3-D image data sets for pathologists. Several automated analysis steps can be performed for segmentation and succeeding quantification. However tumour material is in contrast to isolated or cultured cells even for visual inspection, a difficult material. For the present a fully automated digital image analysis of 3 D data is not in sight. A semi-automatic segmentation method is thus presented here. PMID- 9373711 TI - Cytometric DNA analysis and prognostic biomarkers in breast carcinoma. Expression of P53 product in the different ploidy classes. AB - The aim of the study was to correlate the DNA Index (DI) and S-phase fraction (SPF) values determined by multiparametric flow cytometry in breast cancer (mainly T1 and T2 stages) with several clinico-pathologic variables and other biological parameters. For this purpose, a total of 136 breast cancers were submitted to flow cytometry and to several types of immunohistochemical analyses. Among clinico-pathologic data we considered pT, pN and grade and among immunohistochemical markers, hormonal receptors, P53, c-erbB-2 and MIB-1. We found that DNA aneuploidy was strongly correlated with high tumoral grade, absence of hormonal receptors, high proliferation, as shown by high MIB-1 (> or = 36%) and SPF values (> or = 13.3%), and P53 positivity. Grouping the tumours according to their DI values, we observed a relative significantly higher correlation of the near-triploid range carcinomas (DI 1.40-1.60) with immunohistochemical expression of P53 (p = 0.0001). Near-triploid DI was also associated with a high proliferative activity, expressed both by SPF (p = 0.0001) and MIB-1 reactivity (p = 0.0001), high tumoral grade (p = 0.0001) and presence of axillary metastases (p = 0.03). These data suggest that DNA near-triploid tumours in breast cancer may have a more aggressive behaviour in comparison with other DI classes. PMID- 9373712 TI - The reproducibility of nuclear morphometric measurements in invasive breast carcinoma. AB - The intraobserver and interobserver reproducibility of computerized nuclear morphometry was determined in repeated measurements of 212 samples of invasive breast cancer. The influence of biological variation and the selection of the measurement area was also tested. Morphometrically determined mean nuclear profile area (Pearson's r 0.89, grading efficiency (GE) 0.95) and standard deviation (SD) of nuclear profile area (Pearson's r 0.84, GE 0.89) showed high reproducibility. In this respect, nuclear morphometry equals with other established methods of quantitative pathology and exceeds the results of subjective grading of nuclear atypia in invasive breast cancer. A training period of eight days was sufficient to produce clear improvement in consistency of nuclear morphometry results. By estimating the sources of variation it could be shown that the variation associated with the measurement procedure itself is small. Instead, sample associated variation is responsible for the majority of variation in the measurements (82.9% in mean nuclear profile area and 65.9% in SD of nuclear profile area). This study points out that when standardized methods are applied computerized morphometry is a reproducible and reliable method of assessing nuclear atypia in invasive breast cancer. For further improvement special emphasize should be put on sampling rules of selecting the microscope fields and measurement areas. PMID- 9373713 TI - Treatment of chronic critical leg ischaemia--a cost benefit analysis. PMID- 9373714 TI - Ceramide signalling: regulatory role in cell proliferation, differentiation and apoptosis in human epidermis. AB - The stratum corneum of vertebrates is a major structural compartment that provides mechanical protection and prevents skin desiccation. The water barrier function of the stratum corneum was first reported in 1944, and this was shown later to be associated with multilayered lipid lamellae localized in the extracellular spaces. The major lipid components isolated from the cornified epidermal layers are ceramides, which belong to the class of sphingolipids, cholesterol and free fatty acids; their biosynthesis is in tight relationship with the cutaneous barrier function. In studies in which the barrier is artificially disturbed, lipid biosynthesis is found to be directly regulated by barrier permeability. As mentioned above, the ceramides involved in this process are located in the extracellular spaces of the upper epidermal layers, whereas sphingomyelin, the most common sphingolipid, is an integral part of the bilayer plasma membrane of the keratinocytes. During the last few years, however, increasing evidence has shown that sphingolipids may also take part in cell signalling, and the term 'sphingomyelin cycle' has been coined to describe this novel path-way of signal transduction. Intracellular messengers of the sphingomyelin cycle are ceramides as the products of an agonist-stimulated sphingomyelin hydrolysis. Increased levels of intracellular ceramides induce cell differentiation and/or apoptosis and reduce cell proliferation. In contrast to the extracellular barrier-forming ceramides which are complex partly O-acylated species containing long-chain fatty acids, intracellular signal-transducing ceramides are not O-acylated and have acyl chain lengths of 16 and 18 carbon atoms. We present here a review of our present knowledge on the sphingomyelin cycle as a possible signal transduction pathway in the human epidermis. We discuss the common origin of extracellular ceramides constituting the lipid barrier and of intracellular ceramides generated by agonist-stimulated sphingomyelin hydrolysis and serving as second messengers. A summary of alterations in sphingolipid metabolism and lipid composition of the epidermis in diseased skin is also given and the possible use of different sphingolipids for therapy is envisaged. PMID- 9373715 TI - Gene expression of types I and III collagen, decorin, matrix metalloproteinases and tissue inhibitors of metalloproteinases in skin fibroblasts from patients with systemic sclerosis. AB - Cultured fibroblasts from patients with systemic sclerosis (SSc) and normal individuals were examined for gene expression of types I and III collagen, decorin, matrix metalloproteinases (MMP) MMP-1, MMP-2, and MMP-3, tissue inhibitors of metalloproteinases (TIMP) TIMP-1 and TIMP-2, urokinase- and tissue type plasminogen activators (u-PA and t-PA). Fibroblasts from patients with early stage SSC (less than 1 year duration of disease) exhibited higher levels of types I and III procollagen, decorin, MMP-1, MMP-3, TIMP-1, and PAs than those from normal individuals. The gene expression of procollagen alpha 1(I) and TIMP-1 mRNAs were increased, but those of decorin, MMP-1, MMP-2, and MMP-3 were decreased, in fibroblasts from SSc patients with mid-stage SSc (2 to 4 years duration) as compared with those from normal individuals. In contrast, no significant difference in gene expression was found between fibroblasts from normal individuals and from patients with late-stage SSc (more than 6 years duration). These results suggest that gene expression of collagen, decorin, and degrading factors is dynamically modulated during fibrillogenesis. The responses of procollagen alpha 1(I) mRNA to IL-1 and TGF-beta were lower in fibroblasts from SSc patients with early and mid-stage disease, but not in those from patients with-late stage disease, than in control fibroblasts, which indicates that these cytokines may be involved in the earlier phases of fibrosis in SSc. PMID- 9373717 TI - Localization of calbindin-D28k in normal and incised mouse skin: immunohistochemical and immunoblot analysis. AB - The subcellular localization of the protein calbindin-D28k in normal and incised mouse skin was investigated by immunohistochemical staining and immunoblot analysis. In normal skin, the presence of calbindin-D28k was demonstrated in both the nucleus and the cytoplasm of epidermal keratinocytes. Higher levels of calbindin-D28k were detected in the nucleus than in the cytoplasm. Following incision, the levels of calbindin-D28k were significantly decreased in epidermal keratinocytes, particularly in the nucleus, compared with those in normal skin. The immunohistochemical staining and immunoblot analysis showed nuclear calbindin D28k to be decreased or absent during a 10-day observation period following skin incision. Based on these findings, it is suggested that calbindin-D28k may be distributed in both the nucleus and cytoplasm of epidermal keratinocytes in mice, and this protein may be involved in active cell proliferation of the epidermis induced by skin incision. PMID- 9373716 TI - Clinicopathological and prognostic relevance of Rap1-GAP expression in melanocytic tumors. AB - Rap1-GAP protein has been identified as an inactivator of Rap1 activity, a putative endogenous antagonist of Ras proteins. The Rap1-GA1 locus maps to 1p36.1 35, the region which may harbor a gene for familial melanoma. In the present immunohistochemical study we analyzed the clinicopathological and prognostic relevance of Rap1-GAP expression in 60 benign and 103 malignant melanocytic tumors. Cytoplasmic immunoreactivity was detected in the cells of 27/60 nevi (45%) and 59/103 melanomas (57%). In the latter group the frequency of Rap1-GAP expression increased (P < 0.05) with the thickness of primary tumors and was highest in metastatic lesions. Rap1-GAP protein was detected in 15/19 subsequently recurring primary melanomas (79%) but only in 32/67 tumors (47%) of patients who remained free of disease (P < 0.05) for at least 6 years. Five out of six recurring thin melanomas (< 2 mm) were found to be immunoreactive. Although being no indicator for malignant transformation of melanocytic lesions, Rap1-GAP overexpression may represent a useful marker for identifying thin high risk melanomas. Cytoplasmic expression of Rap1-GAP has also been observed in the cells of skin appendages and in keratinocytes, particularly in suprabasal layers of the epidermis. Therefore, Rap1-GAP is likely to be associated with cellular growth and/or differentiation. However, the present study did not provide evidence that this gene, despite its chromosomal localization, represents an early melanoma gene. PMID- 9373718 TI - Culture of reconstructed epidermis in a defined medium at 33 degrees C shows a delayed epidermal maturation, prolonged lifespan and improved stratum corneum. AB - In this study we compared human keratinocyte cultures grown at the air-liquid interface on de-epidermized dermis at 33 degrees C or at 37 degrees C in two different culture media: medium I--a fully defined serum- and EGF-free medium; and medium II-a serum- and EGF-containing medium. Cultures grown in medium II were initially hyperproliferative followed rapidly by senescence, and had a high triglyceride content. The hyperproliferation was ascribed to the presence of EGF in the medium. In contrast, cultures grown in medium I at 33 degrees C showed a greatly improved balance between cell proliferation and differentiation. They had a prolonged lifespan of at least 32 days without a significant decrease in the number of living cell layers, a rate of proliferation similar to that of native epidermis and a low triglyceride content. Culturing at 37 degrees C increased the rate of differentiation without affecting the rate of proliferation. Furthermore, both at 33 degrees C and at 37 degrees C, keratin 6 was expressed only in the first suprabasal layer but was expressed in all suprabasal layers in cultures grown in medium II. High keratin 6 expression was not directly linked to hyperproliferation but to deregulated terminal differentiation. Involucrin, transglutaminase and SPRR1 were abnormally expressed irrespective of the culture conditions used, whereas SKALP expression was decreased in cultures grown in medium I. The epidermal lipid profile was better in cultures grown in medium I; the relative amounts of ceramides, free fatty acids and cholesterol being comparable to native epidermis. Small-angle X-ray diffraction showed a slightly improved structural organization of stratum corneum lipids as demonstrated by the appearance of second- and third-order peaks of the 12-nm long phase and a marked reduction in the polycrystalline cholesterol peak. PMID- 9373719 TI - Morphological alteration of fibroblasts mechanically stressed in a collagen lattice. AB - The behavior of fibroblast-populated collagen lattices under mechanical stress was studied. Lattice retraction was blocked to allow the application of mechanical stress by contraction of the fibroblasts against the fixed ends of the lattice. The forces were modulated by varying the collagen/fibroblast ratio and the amount of collagen fibrils produced, by which the forces were transmitted. Transmission electron microscopy showed several disturbances of fibroblast ultrastructure, with empty and full vacuoles, lamellar bodies and signs of cytolysis. It is suggested that the morphological alterations in the fibroblasts may constitute a feedback reaction to the mechanical stress. PMID- 9373720 TI - Granulocyte and macrophage colony-stimulating factors stimulate proliferation of human keratinocytes. PMID- 9373721 TI - Detection of programmed cell death in anagen hair follicles of guinea pig skin by labeling of nick ends of fragmented DNA. PMID- 9373722 TI - Modulation of histamine release in vitro by FK506 and interleukin-3 is determined by sequence of incubation. PMID- 9373723 TI - Effects of pentobarbital on pharmacokinetics and pharmacodynamics of a potent fibrinogen receptor antagonist, L-734,217, in dogs. AB - Effects of pentobarbital on pharmacokinetics and pharmacodynamics of L-734,217, a potent fibrinogen receptor antagonist, were studied in male dogs. L-734,217 was given intravenously at 0.01 mg kg-1, in a cross-over fashion, to conscious dogs or to dogs anesthetized with pentobarbital. Plasma concentrations of L-734,217 were measured using a radioimmunoassay and inhibitory effects on ex vivo platelet aggregation induced by ADP or collagen were determined. In pentobarbital-treated dogs, L-734,217 plasma concentrations during the first 3 h collection period were significantly higher than those in the control animals. Corresponding to the increased plasma levels, the mean ex vivo inhibitory effects on ADP- or collagen induced platelet aggregation in dogs under anesthesia appeared greater than in those without the anesthetic treatment. Pharmacokinetic analysis revealed a modest, but significant (up to 40%) elevation in the area under the plasma concentration-time curve during 6 h of the drug administration, and a reduction in L-734,217 plasma clearance and volumes of distribution, in the anesthetized dogs. Analysis of pharmacodynamic data indicated that the EC50 and the Hill coefficient of the platelet aggregation response-plasma concentration curve were not altered by pentobarbital treatment. The results are in agreement with the findings that the administration of pentobarbital alone (in the absence of L 734,217) did not affect appreciably the ex vivo platelet aggregatory responses. In a separate group of dogs, L-734,217 was found to be metabolically stable, and was eliminated unchanged renally (64 +/- 4%) and hepatically (32 +/- 6%). In addition, L-734,217 did not bind substantially to canine plasma proteins or blood cellular components. It is possible that alterations of regional hemodynamics, reportedly mediated by pentobarbital, contributed to changes observed in the present study. That is, alterations occurred in L-734,217 elimination and distribution processes which resulted in an increase in drug plasma levels. Since pentobarbital anesthesia influenced only the pharmacokinetics, and not the pharmacodynamics, of L-734,217, the apparent increases in the inhibition of platelet aggregation responses observed following L-734,217 administration to the anesthetized dogs were probably sequential effects of the pharmacokinetic interactions. PMID- 9373724 TI - Pharmacokinetic evaluation of a selegiline pulsatile oral delivery system. AB - Selegiline is a selective, irreversible inhibitor of MAO-B, used in the treatment of Parkinson's disease, either alone or as an adjunct to L-DOPA. The sole recommended dosing regimen is 5 mg given in the morning and at noon with breakfast and lunch. A pulsatile oral dosage form was developed to mimic the conventional tablet release from two oral administrations separated by 4 h, to permit once-daily dosing and increase compliance. The pharmacokinetics of the pulsatile delivery system was studied in six healthy male volunteers. The plasma concentration-time profile from the pulsatile system of selegiline and metabolites is dissimilar to that obtained from the 5 mg bid administration of the conventional tablet and cannot be considered to be bioequivalent. The initial pulse of the delivery system is rapidly absorbed but to a lesser extent than the conventional regimen; the second pulse exhibits absorption which is delayed and prolonged. The decrease in the selegiline concentration may be due to the less absorptive surface of the lower GI tract which is available to the second pulse. Another reason could be the disparity between the in vitro and in vivo release profiles from the second pulse. Compartmental analysis indicates that the ratio of formation-absorption rate constant for the selegiline to N-desmethylselegiline pathway decreases from 1.57 +/- 1.04 for the first pulse to 0.61 +/- 0.54 for the second pulse of the pulsatile delivery system, suggesting that the upper portion of the GI tract has a greater capacity to convert selegiline to N desmethylselegiline than the lower GI tract. The lack of in vivo and in vitro correlation is most likely due to site specific absorption/metabolism. Regimen has been previously shown to be a significant factor in estimating the extent of selegiline and metabolite exposure following oral administration. The inequivalence of dosing regimens of the same total daily dose may ultimately be linked to the saturability of gut wall metabolism. This phenomenon may preclude the development of novel delivery systems designed to mimic the recommended dosing regimen of the conventional Eldepryl tablet. PMID- 9373726 TI - Oral absorption of anti-aids nucleoside analogues: 3. Regional absorption and in vivo permeability of 2',3'-dideoxyinosine in an intestinal-vascular access port (IVAP) dog model. AB - The absolute oral and regional intestinal bioavailabilities (BAs) and pharmacokinetics (PK) of 2',3'-dideoxyinosine (ddI), a nucleoside analog used in the treatment of human immunodeficiency virus (HIV) infection, were investigated in an in vivo intestinal-vascular access port (IVAP) dog model. The mean (+/- SD) absolute regional intestinal BAs of ddI were 49.6 +/- 8.8, 42.7 +/- 7.9, and 13.6 +/- 5.4% after the bolus administration of unbuffered solutions containing 250 mg ddI into the duodenum, ileum, and colon of IVAP beagle dogs, respectively. The BA of the orally administered Videx 250 mg buffered chewable tablets was 44.9 +/- 1.6%. ddI absorption and disposition PK were modeled by simultaneously fitting intravenous, oral, and intestinal plasma level versus time data using a physiologically based PK model. The region-specific apparent absorption rates followed the rank order duodenum > ileum > colon. Apparent regional in vivo intestinal permeabilities correlated well with previously determined regional permeabilities in rats. The intestinal pH was monitored using a radiotelemetric pH monitoring system since ddI is unstable in an acidic environment. While the pH was found to be lower in the duodenum and proximal jejunum (approximately pH 6) than in the ileum or colon (pH > or = 7.0), ddI is reasonably stable across the entire pH range of the dog small intestine. These studies demonstrate that the regional reduction in ddI BA is consistent with a reported distal reduction in intestinal permeability and appears to be a significant contributing factor to the high degree of absorption variability reported for ddI. PMID- 9373725 TI - Steady-state pharmacokinetics of corticosteroid delivery from glucuronide prodrugs in normal and colitic rats. AB - Ulcerative colitis and Crohn's colitis are chronic intestinal diseases usually treated with various nonsteroidal antiinflammatory agents to maintain remission. Corticosteroids, while useful in acute treatment of these diseases, present side effects generally too serious to allow maintenance therapy. Colon-specific drug delivery may permit use of corticosteroids for maintenance therapy if doses can be reduced while maintaining efficacy. In this study, two prodrugs (dexamethasone beta-D-glucuronide (DXglrd) and budesonide-beta-D-glucuronide (BUDglrd)) were administered by intragastric (i.g.) infusion to conventional and colitic rats. In addition, dexamethasone (DX) and budesonide (BUD) were administered either i.g. or subcutaneously (s.c.) to healthy and colitic rats. Colon-specific delivery was assessed using the drug delivery index (DDI). In conventinal rats, DDIs for DXglrd ranged from about five to as high as 11 in the luminal contents relative to DX administered sc or i.g. DDI values were also elevated in the mucosa of both healthy and colitic rats following i.g. administration of DXglrd. BUD was delivered somewhat less effectively from BUDglrd to the rat large intestine than was DX from DXglrd. The data are consistent with efficacy studies and support the conclusion that local delivery of corticosteroids to the large intestine is due, at least in part, to higher levels of drug delivery into the mucosal tissues. PMID- 9373727 TI - Nonlinear perpendicular least-squares regression in pharmacodynamics. AB - Currently available software for nonlinear regression does not account for errors in both the independent and the dependent variables. In pharmacodynamics, measurement errors are involved in the drug concentrations as well as in the effects. Instead of minimizing the sum of squared vertical errors (OLS), a Fortran program was written to find the closest distance from a measured data point to the tangent line of an estimated nonlinear curve and to minimize the sum of squared perpendicular distances (PLS). A Monte Carlo simulation was conducted with the sigmoidal Emax model to compare the OLS and PLS methods. The area between the true pharmacodynamic relationship and the fitted curve was compared as a measure of goodness of fit. The PLS demonstrated an improvement over the OLS by 20.8% with small differences in the parameter estimates when the random noise level had a standard deviation of five for both concentration and effect. Consideration of errors in both concentrations and effects with the PLS could lead to a more rational estimation of pharmacodynamic parameters. PMID- 9373728 TI - The pharmacokinetics of glycyrrhizin and its restorative effect on hepatic function in patients with chronic hepatitis and in chronically carbon tetrachloride-intoxicated rats. AB - The relationships between the pharmacokinetic behaviour of glycyrrhizin and its restorative effect for hepatic function were investigated in patients with chronic hepatitis and in rats chronically treated with carbon tetrachloride (CCl4 treated rats). In patients, the restorative effects in plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were 62.2 +/ 7.4 and 64.4 +/- 7.5%, respectively, after daily 80 mg intravenous (i.v.) doses of glycyrrhizin for 2 weeks, and 63.1 +/- 19.1 and 68.7 +/- 15.2% after 120 mg doses. The present work suggests that the threshold plasma glycyrrhizin concentration for sufficient effect is near 5 micrograms mL-1. In rats, the total body clearance (Cltot) for glycrrhizin in the CCl4-treated rats after i.v. administration of glycyrrhizin (5 mg kg-1 dose) was three-tenths of that of the control, and the t1/2 for glycyrrhizin was 3.4-fold longer than that of the control. A good correlation was observed between Cltot and AST (r = -0.838) or ALT (r = -0.873) activity in both rats. When glycyrrhizin was administered intraperitoneally (i.p.) three times a week for 2 weeks, both the AST and ALT activities in the CCl4-treated rats showed a greater improvement than for a 10 mg kg-1 dose. Furthermore, the finding on the threshold plasma concentration in patients as above was also supported from the results of the experiments in rats. PMID- 9373729 TI - A dose-dependent pharmacokinetic study on caffeic acid in rabbits after intravenous administration. AB - The dose-dependent pharmacokinetics of caffeic acid (CA) were studied in rabbits. Three different doses (5, 10, and 25 mg kg-1) were administered intravenously to six rabbits each. The concentration-time profiles for CA could be fitted by a two compartment model for each dose. The results showed that total-body clearance and elimination rate constant from the central compartment (k10) after a 5 mg kg-1 dose were greater than those after the other two doses. Furthermore, the terminal elimination half-life (beta half-life) and mean residence time (MRT) after a 5 mg kg-1 dose were less than after the other doses. The AUC value increased linearly with dose within the range of 10-25 mg kg-1. Most of the unchanged caffeic acid was excreted in the urine within 2 h. The percentage of unchanged caffeic acid excreted in the urine was 63.4, 60.0, and 55.4% after doses of 5, 10, and 25 mg kg-1, respectively, which was not significantly different. However, significant differences in the renal clearances and renal excretion rate constants were observed with a 5 mg kg-1 dose compared to the other doses. On the other hand, nonrenal clearances and nonrenal excretion rate constants showed no dose-related differences. The differences observed in total-body clearance, k10, beta half life, and MRT between a 5 mg kg-1 dose and the other doses can be explained on the basis of the differences in renal clearance and renal excretion rate constants. PMID- 9373730 TI - Improved oral bioavailability of the hypocholesterolemic DMP 565 in dogs following oral dosing in oil and glycol solutions. PMID- 9373732 TI - Long-term treatment with recombinant interferon alpha-2b prolongs survival of asymptomatic HIV-infected individuals. AB - RATIONALE AND OBJECTIVE: Early long-term treatment with recombinant interferon (IFN) alpha-2b delayed disease progression in asymptomatic Human Immunodeficiency Virus (HIV) carriers in a randomized trial that lasted from October 1987 to February 1992 (14). The aim of the work reported in this paper was to observe if there was also an effect on survival when the same patients were followed-up further. DESIGN AND INTERVENTIONS: IFN alpha-2b was given 3 x 10(6) IU, 3 times weekly. The control group did not receive any treatment. The main end-point for this evaluation was death due to any cause. The deadline was August 1995. POPULATION: Subjects were anti-HIV-1 seropositive, Western blot-confirmed, asymptomatic (CDC group II), or with generalized lymphadenopathies (CDC group III). The groups had 79 (control) and 83 (IFN) patients. MAIN RESULTS: Mean survival was longer in the IFN group (95% CI: 127-152 vs. 101-120 months since infection or 80-90 vs. 70-82 months since the start of treatment). Survival rates were higher in IFN-treated individuals (61-77% vs. 24-54% at 10 years of infection or 53-69% vs. 34-52% at 7 years of treatment or follow-up). It was also confirmed that disease progression is significantly slower in IFN-treated patients. There were 23.4 vs. 3.2% long-term survivors in the IFN and control groups, respectively (p = 0.005). IFN-treated patients had fewer AIDS-related malignancies (5 vs. 11), mainly Kaposi's sarcomas (1 vs. 5). This difference was not statistically significant, but clinically interesting. There was no difference in survival if measured since the onset of AIDS. CONCLUSION: IFN alpha treatment given from the early stages of infection, but not after the appearance of AIDS symptoms, can prolong survival. PMID- 9373731 TI - Augumentation of splenic antitumor immunity by local immunotherapy in gastric cancer patients. AB - We previously reported that the antitumor effect of OK-432, a streptococcal preparation, was markedly augmented when this agent was injected into tumors together with fibrinogen. In order to elucidate the effect of this treatment on the spleen, we assessed splenic function in gastric cancer patients receiving preoperative local immunotherapy with OK-432 and fibrinogen. Immunohistochemical studies of the spleen at 7 days after intratumoral injection therapy revealed numerous macrophages phagocytizing OK-432 in the splenic sinuses. Phenotypic analysis of splenocytes by flow cytometry revealed an increase in the CD4/CD8 ratio and in the expression of HLA-DR, CD25, and Leu M3 by splenic T cells of the patients treated with OK-432 plus fibrinogen when compared to patients treated with OK-432 alone or untreated patients. Splenic T cells from patients treated with OK-432 plus fibrinogen showed significantly higher cytotoxicity against Daudi and K562 cells than T cells from control patients (p < 0.05), and culture of these splenic T cells with recombinant IL-2 induced the expansion of lymphokine-activated killer cells. These results demonstrate that local immunotherapy with a mixture of OK-432 and fibrinogen effectively augumented splenic antitumor immunity in gastric cancer patients. PMID- 9373733 TI - Treatment of head and neck cancers with BRMs--prolongation of survival. AB - It has been reported that immunologic function is deteriorated in head and neck cancer patients by primary therapies such as surgery, irradiation and chemotherapy or tumor itself. As previously described by us, immunologic dysfunction in such patients may be recovered by treatment with BRMs. In the present study, we investigated the effects of BRMs on survival of patients who had primarily been treated in our clinic. Fifty-one patients (23 patients; Stage I or Stage II, 28 patients; Stage III or Stage IV) were treated with BRMs (BRM group), and 49 patients (22 patients; Stage I or Stage II, 27 patients; Stage III or Stage IV) were employed as controls (Control group). The results obtained were as follows: (1) In patients of all Stages, the survival period was significantly (p < 0.05) longer in BRM group than in Control group; (2) The survival periods of patients of Stage I or Stage II were not different between the groups; and (3) The survival period of BRM group was significantly (p < 0.05) longer than that of Control group in patients of Stage III or Stage IV. There were observed more patients in BRM group who survived for a prolonged period. These results suggest that BRMs may be useful for recovering immunologic function in head and neck cancer patients particularly of Stage III or Stage IV who usually receive multimodality therapy. PMID- 9373734 TI - In vivo and in vitro effects of Sizofiran on the human neutrophils and the serum opsonic activity. AB - In this paper, we examine the effects of SPG, which is a well known BRM, both in vivo and in vitro on the neutrophilic ROS production and the serum opsonic activity by the chemiluminescence technique using luminol as a probe. To investigate the in vivo effects, SPG was administered to 12 healthy male volunteers and two phases of enhancement of the neutrophilic ROS production and the serum opsonic activity was observed. In vitro, the addition of SPG showed a dose-dependent suppression. To investigate the mechanisms in these contradictory effects of SPG, supernatants of a lymphocytes culture medium in the presence of SPG with or without mitogen were added to the neutrophils. The addition of supernatants at a lower concentration of SPG (0.01 mg/ml) with mitogens showed significant preventive effects on the neutrophilic ROS production for the duration of incubation. This suggests that cytokines derived from lymphocytes may contribute to the in vivo effects of SPG. SPG can play an important role in the host's defense against microbe infections by enhancing it's effect on non specific immunity when administered in vivo. PMID- 9373735 TI - Modulation of cisPlatin cytotoxicity by interleukin-1 alpha and resident tumor macrophages. AB - The modulation of cisPlatin cytotoxicity by interleukin-1 (IL-1 alpha) was studied in cultures of SCC-7 tumor cells with and without tumor macrophages to examine potential mechanisms for the synergistic antitumor activity of cisPlatin and IL-1 alpha in SCC-7 solid tumors. Neither IL-1 alpha nor tumor macrophages affected the survival of clonogenic tumor cells and IL-1 alpha had no direct effect on tumor cell growth in vitro. Macrophages had no direct effect on cisPlatin sensitivity (IC90 = 6.0 microM), but, the addition of IL-1 alpha (500 2000U/ml) to co-cultures of cisPlatin pretreated tumor cells and resident tumor macrophages increased cell killing (IC90 = 3.1 microM). Similar responses were seen in primary cultures treated with cisPlatin before IL-1 alpha. The modulation of cisPlatin cytotoxicity by IL-1 alpha exhibited a biphasic dose response that paralleled the IL-1 alpha dose dependent release of H2O2 by resident tumor macrophages. Further, IL-1 alpha modification of cisPlatin cytotoxicity was prompt and inhibited by catalase. CisPlatin and exogenous H2O2 (50 microM) produced more than additive SCC-7 clonogenic cell kill and hydroxyl radicals played an important role in the response. Interleukin-1 modulation of cisPlatin cytotoxicity was schedule dependent. IL-1 alpha treatment for 24 hrs, before cisPlatin, produced drug resistance (IC90 = 11.1 microM). Our study shows that IL 1 alpha can stimulate tumor macrophages to release pro-oxidants that modify cellular chemosensitivity in a schedule and dose dependent fashion. Our findings may also provide a mechanistic explantation for the synergistic antitumor activity of cisPlatin and IL-1 alpha in vivo. PMID- 9373736 TI - Z-100, a polysaccharide-rich preparation extracted from the human type Mycobacterium tuberculosis, improves the resistance of Meth-A tumor-bearing mice to endogenous septic infection. AB - The effect of Z-100, an immunomodulatory arabinomannan extracted from Mycobacterium tuberculosis, on cecal ligation and puncture (CLP)-induced sepsis in mice bearing Meth-A fibrosarcoma was investigated. When normal BALB/c mice were subjected to the CLP procedure, their mortality rate was 17%. On the other hand, an increased mortality was observed in tumor-bearing mice subjected to CLP 10 days after tumor inoculation, and then all mice died when tumor-bearing mice were subjected to CLP 20 days after tumor inoculation. However, the increased percent mortality was decreased by 50% when these mice were injected intraperitoneally with a 10 mg/kg dose of Z-100. When splenocytes (5 x 10(7) cells), obtained from Meth-A tumor-bearing mice 20 days after tumor inoculation, were transferred intravenously to normal mice (recipient mice), mortality of these recipient mice were increased by 62% as compared with that of the control (22%). However, no increased mortality (25%) was observed in recipient mice which were transferred with splenocytes from tumor-bearing mice injected intraperitoneally with Z-100 (10 mg/kg). In addition, suppressor cell activity was demonstrated in splenocytes from Meth-A tumor-bearing mice at 20 days after tumor inoculation using one-way mixed lymphocyte reaction. However, the suppressor cell activity was significantly decreased by the intraperitoneal administration of a 10 mg/kg dose of Z-100 (p < 0.01). The increase of mortality in recipient mice by adoptive transfer of mononuclear cells (MNCs) from tumor bearing mice was not detected when these MNCs were treated with anti-Thy 1.2 monoclonal antibody (mAb), anti-Lyt 2.2 mAb or anti-CD11b mAb, but an increase was seen with anti-Lyt 1.2 mAb or anti-immunoglobulin antiserum treated MNCs. These results suggest that the suppressor cells affect the mortality of CLP induced sepsis and Z-100 may have a therapeutic activity against opportunistic infections in immunocompromised hosts through the regulation of suppressor T cells. PMID- 9373737 TI - Cytotoxic activity of doxorubicin "loaded" neutrophils against human mammary carcinoma (HTB-19). AB - Neutrophils were intra-cellularly "loaded" with the chemotherapeutic agent, doxorubicin applying a variety of incubation conditions in order to identify parameters which maximize chemotherapeutic incorporation, while simultaneously preserving optimal viability and chemotactic responsiveness. Doxorubicin "loaded" neutrophils (DLN) were produced in triplicate at different combinations of incubation conditions such as temperature (4 degrees C, 37 degrees C); duration (0, 1, 2 hours); and doxorubicin concentration (20, 40, 60 micrograms/ml). Chemotactic responsiveness of rinsed DLN preparations was subsequently assessed against the neutrophil peptide chemotactic agent, formyl methionyl leucyl phenylalanine (fMLP, 10(-6) M) utilizing a modified 96-well Boyden chemotactic chamber apparatus. Viable, fMLP-responsive DLN preparations were subsequently detected with MTT vitality staining reagent. At sub-physiological incubation temperatures (4 degrees C), profound declines in the viability of DLN preparations were detected when simultaneously incubated with doxorubicin formulated at concentrations greater than 10 micrograms/ml. In contrast, DLN preparations incubated at 37 degrees C displayed diminished viability only when incubated with doxorubicin formulated at a concentration of 60 micrograms/ml. Viable DLN populations were subsequently evaluated to determine their ability to exert in vitro cytotoxic activity against monolayer populations of human mammary carcinoma (HTB-19) propagated in a tissue culture environment. The lethal effect which DLN preparations inflicted towards HTB-19 populations was substantially greater than was observed with an equivalent population of untreated neutrophils. Maximal in vitro cytotoxic activity was detected with DLN preparations produced at 37 degrees C in the presence of doxorubicin formulated at a concentration of 40 micrograms/ml. In contrast, DLN preparations produced at an incubation temperature of 37 degrees C, and a doxorubicin concentration of 20 micrograms/ml displayed relatively lower levels of in vitro cytotoxic activity against HTB-19 monolayer populations. The degree of in vitro cytotoxic activity exerted against HTB-19 monolayer populations by DLN preparations was directly influenced by the duration of the challenge period. Maximal in vitro cytotoxic activity was observed when HTB-19 monolayer populations were challenged with DLN preparations for a period of 96-hours duration at 37 degrees C. Challenge periods of 48-hours duration produced levels of in vitro cytotoxic activity which were substantially lower than those observed for challenge periods of 96-hours duration. Optimal in vitro cytotoxic activity was recognized when DLN preparations were allowed to establish direct contact with HTB-19 monolayer populations at an estimated DLN:HTB-19 cellular ratio of approximately 5:1 (37 degrees C, CO2, 6%). Significantly less in vitro cytotoxic activity was recognized when DLN preparations were only permitted indirect cellular contact with HTB-19 monolayer populations which was achieved through the application of a semi-permeable 3 microM pore membrane partition. In vitro cytotoxic activity of DLN populations was not inhibited by the anti-oxidant agent, dimethyl sulfoxide (DMSO), but was inhibited in the presence of glutathione (GSH), superoxide dismutase (SOD), and vitamin E (alpha-tocopherol). Similarly, in vitro cytotoxic activity of DLN populations was also inhibited in the presence of sodium heparin (serine esterase inhibitor), and dexamethasone (inhibitor of neutrophil activation-degranulation phenomenon). Experimental results observed in these investigations collectively imply that the in vitro cytotoxic activity exerted by DLN preparations against HTB-19 populations is in part attributable to neutrophil-mediated cytotoxic immunity. This innate property of neutrophil populations involves their capacity to generate highly reactive oxygen "free" radical species (O2, HO, H2O2), and synthes PMID- 9373739 TI - Paediatric audiology and cochlear implantation in the UK: taking off in the fast lane. PMID- 9373738 TI - The in vitro effect of new muramyl peptide derivatives on cytotoxic activity of NK (natural killer) cells from hamsters bearing Ab Bomirski melanoma. AB - The modulation of NK activity by muramyl dipeptides derivatives against Ab (amelanotic) Bomirski melanoma and human erythroleukemia K562 cells was studied in vitro. The stimulatory effect was observed for 3 of 7 muramyl dipeptides: MDP(L-Ala)C921, MDPC857 and L18-MDP(Ala) in relation to cytotoxic activity of NK cells obtained from peripheral blood and spleen of healthy and Ab Bomirski melanoma bearing hamsters. An increased of cytotoxic activity NK cells isolated from animals before and during the transplantable phase of the tumor against K562 was found. A similar stimulation was received for NK cells obtained from animals against their own melanoma cells. The most significant influence of examined MDP derivatives on the cytotoxic activity of NK cells were obtained from animals between 10 to 12 days of tumor growth. The extent of the modulation of cytotoxic activity of NK cells was dependent on its initial value both in healthy control and Ab Bomirski melanoma bearing hamsters. If natural cytotoxic activity was high the stimulatory effect of the examined MDP derivatives was only slightly expressed. PMID- 9373740 TI - The effect of head size on the auditory brainstem response for two breeds of dog. AB - Many studies have shown that the auditory brainstem response (ABR) is influenced by the sex of the subject. The explanation offered most often for this sex difference is the smaller head size and brain dimensions in the female. Since breeds of dog have different head sizes, this makes them useful subjects to test the hypothesis that ABR latency covaries with head size. Subjects comprised 20 Dalmatians and 20 Jack Russell terriers. The maximum width of the head was 123 +/ 8 mm in the Dalmatian and 88 +/- 5 mm in the Jack Russell. An auditory brainstem response was carried out using a click stimulus at 75 dB nHL. The latency of wave V and the I-V interval was longer (0.3 and 0.17 ms respectively) in the Dalmatian, although the correlation of these measurements with head size (which ranged from -0.2 to +0.3) was not statistically significant. These findings do not support the theory that differences in ABR latency are due to differences in head size per se. Correlation of latency with body temperature and with age was also weak and not statistically significant. PMID- 9373741 TI - Behavioural and autonomic responses to sound in pre-term and full-term babies. AB - The pattern of motor (body movement) and autonomic (heart rate and respiration) responses to no sound and sound trials were compared in 20 pre-term and 22 full term neonates. Sound levels were calibrated using neonatal ear-sized couplers to produce, in the neonatal ear, sound levels of 80, 90 and 100 dB SPL. Accelerations in heart rate (> or = beats per minute for pre-terms; > or = 7 beats per minute for full-terms) were found to be the best criterion for establishing a possible response using bandpass noise at 80, 90 or 100 dB SPL. Respiration rate decreased in response to sound stimuli, this being significant for the pre-term group for the 100 dB SPL stimulus when comparing the 5 s period post-stimulus with the stimulus period. The number of movements detected during the sound trials was higher than for the control trials, being statistically significant for the pre-term group. These changes were elicited in response to stimuli presented at levels some 20-40 dB lower than for other studies and for behavioural screening because sounds were calibrated in an appropriately sized coupler. It is concluded that the response to sound is different in the pre-term group compared with the full-term group. PMID- 9373742 TI - Managing tinnitus: a comparison of different approaches to tinnitus management training. AB - A series of studies examining the interaction between the characteristics of individual tinnitus sufferers and the effectiveness of the methods used to assist them has been conducted. The first of these studies provided a baseline description of 96 people with tinnitus, according to a range of audiological and psychological variables. In the present paper four differing tinnitus management programmes are described and the related changes in tinnitus perception reported three months after tinnitus management training. For the majority of subjects, the tinnitus was less annoying and less distressing three months after attending tinnitus management training. However, the majority of subjects reported no change in tinnitus loudness, or tinnitus awareness and no change in their tinnitus coping ability. Subjects receiving low level white noise stimulation reported greater improvement in tinnitus coping ability than subjects who received information and relaxation training, although there was no associated improvement in tinnitus awareness. Subjects' beliefs about tinnitus and preferred coping style may have influenced the reported benefit or otherwise of the differing tinnitus management techniques. PMID- 9373744 TI - A compact disc containing simulations of hearing impairment. AB - The author has produced a compact disc (CD) which contains a series of simulations of the effects of cochlear hearing loss. The following aspects are simulated: threshold elevation combined with loudness recruitment; reduced frequency selectivity; and threshold elevation, loudness recruitment and reduced frequency selectivity all together. The effects are demonstrated using speech in quiet and in a background of noise, and using a piece of music with a wide dynamic range. The CD also includes simulations of the effect of having a conventional 'linear' hearing aid, and of having aid incorporating dual-channel fast acting compression. Finally, the CD contains demonstrations of the 'occlusion effect' and the benefits of having a deeply fitting earmould or hearing aid. The purpose of this note is to describe some of the uses of the CD for teaching and educational purposes and to indicate which tracks will be most effective for specific purposes. PMID- 9373743 TI - A randomized, controlled trial of the efficacy of a communication course for first time hearing aid users. AB - Many centres include a communication course as part of their auditory rehabilitation. These usually take the form of a small group and include discussion of the effects of hearing loss, use of the hearing aid, hearing tactics and lip reading. To investigate the efficacy of such a rehabilitation programme a randomized, controlled trial of a communication course was undertaken. All subjects were first time hearing aid users; handicap was measured using the Quantified Denver Scale of Communication Function (QDS) at the time of hearing aid fitting, and then 13 weeks later. All subjects had a hearing aid follow-up appointment, but the treatment group (n = 22) also underwent a four week communication course, while the control group (n = 25) had no further rehabilitation. The reduction in handicap measured by the change in QDS was significantly greater for the treatment group than for the control group (Mann Whitney U test, tied p value = 0.014). This indicates that such a communication course is efficacious in reducing handicap. Further research is required to identify the populations that will benefit most from such a course. PMID- 9373745 TI - Audiometer calibration: two neglected areas. AB - British and International Standards for pure tone audiometry require that the static force exerted by the earphone/bone vibrator headband is within certain limits. However, no recommended procedure is given for making force measurements. In addition, standards for audiometers require that linearity of output level is within certain limits. Only a brief outline of a procedure is available for measuring linearity at low intensity levels. Both these areas of audiometer calibration tend to be neglected according to our survey of organizations offering calibration services. Equipment and protocols for measuring both have been developed at the MRC Institute of Hearing Research, and are described. A convenience sample of audiometers gave a wide range of headband forces, many of which do not comply with the relevant standard. Linearity of output at low levels did comply with the relevant standard for all audiometers measured. We recommend the use of simple devices, such as those described, for routine calibration. They are quick and easy to use, give reliable results, and are inexpensive. PMID- 9373746 TI - The wider implications of the Health Visitor Distraction Test consultation. PMID- 9373748 TI - District-based population registers for sickle cell disorders: a role for the haemoglobinopathy clinical nurse specialist? PMID- 9373747 TI - The blue-eyed cochlear implant population. PMID- 9373749 TI - A critical evaluation of Dutch preventive child health care. PMID- 9373750 TI - The parent between the child and the professional--some ethical implications. AB - In this paper ethical implications of parental participation in paediatric care are discussed. The paper is based on interviews with 20 parents, whose children were admitted and operated on at a paediatric surgery department in Sweden. In one part of the interview the parent was invited to speak about situations experienced as problematic during the hospitalization. Three different types of situations were described by the parents as especially problematic. In the first situation the parents' ability to influence their own situation was limited. Parents got upset when staff did not treat them as autonomous persons. In the second type of situation things 'had to be done' to the child, for example the surgery, the anaesthesia, removing an indwelling catheter and giving an enema. The parents understood and accepted this, but the child was sometimes unable to agree usually because of anxiety and fear. In the third type of situation parents felt that professionals did not take them or their child seriously. In order to avoid or alleviate such situations, the professionals ought to mediate a permissive attitude to the expressions of concern. Thus, when the parents worry, the professionals ought to listen more attentively and, whenever possible and adequate, respect their concerns. PMID- 9373751 TI - Speech perception and speech comprehension investigations of pre-term newborns and high-risk neonates of pre-school age. AB - The purpose of this study is to establish whether there is any connection between neonatal morbidity and speech perception and comprehension in children of pre school age who have previously been treated as newborn infants in an intensive care unit. The test applied is a method invented in Hungary for the analysis of global hearing, speech perception and comprehension. The authors summarize the results of their follow-up studies of 52 children with respiratory disorders as newborns, some of whom were born as pre-term and some as full-term newborns with asphyxia. The children have been put into three groups according to their maturity and their birthweight. Newborns with hearing loss and mental retardation were excluded from this study. Of the various neonatal factors the results show: complications of delivery, birthweight, hypoxia, persistent ductus arteriosus, duration of ventilation and complications of respiratory treatment are found to be correlated to perception and comprehension. Incidences of poor achievement obtained in the most characteristic subtests have been compared among the different groups of newborns. The intelligence level of pre-school children is found to be closely correlated to speech perception and comprehension. PMID- 9373752 TI - Infant feeding and maternal concerns about stool hardness. AB - From a questionnaire completed by 195 mothers of infants aged 3-12 weeks we found that significantly more formula than breast-feeding mothers had concerns about stool hardness and had sought professional advice, resulting in both increased use of health care resources and more dietary interventions. PMID- 9373753 TI - Emotionally focused therapy improves marital adjustment in parents of children with chronically ill children. PMID- 9373754 TI - In the UK the transition from youth to adulthood of people with cerebral palsy is poorly planned and co-ordinated. PMID- 9373755 TI - Mack Forster Award Lecture. Receptor nuclear medicine: vasointestinal peptide and somatostatin receptor scintigraphy for diagnosis and treatment of tumour patients. AB - The multiple aspects of radioligand-receptor interactions do not only show a major impact of certain cell surface-bound receptors in the pathophysiology of human disease: the concept of radioligand-receptor interactions has also been extended to the clinic. In particular, naturally occurring peptides, when radiolabelled, are clinically useful for the imaging diagnosis of human disease and have future implications for the treatment of tumour expressing certain target receptors using radiolabelled peptide tracers. The finding that receptors for VIP (vasoactive intestinal peptide) and SST (somatostatin) are overexpressed on tumour cells presents a breakthrough into this direction. Recent data indicate that [123I]-VIP receptor scintigraphy is clinically useful for the in vivo localization of small primary adenocarcinomas, liver metastases and certain endocrine tumours of the gastrointestinal tract. After the successful clinical introduction of the SST analogues [123I]-Tyr3-octreotide and [111In]-DTPA-D-Phe1 octreotide for localization diagnosis of neuroendocrine tumours in 1989, P829, labelled with the more cost-effective radionuclide 99mTc, nowadays promises to be a potential novel diagnostic imaging agent for tumours expressing SST/VIP receptors. Furthermore, the novel SST analogue [90Y]-MAURITIUS is entering the clinic for treatment of VIP/SST receptor-expressing tumours. PMID- 9373756 TI - Mack Forster Award 1997. PMID- 9373757 TI - Metabolic and genetic aspects of familial combined hyperlipidaemia with emphasis on low-density lipoprotein heterogeneity. PMID- 9373759 TI - Vitamin E, oxidative stress and 'healthy ageing'. PMID- 9373758 TI - Postprandial chylomicron and plasma vitamin E responses in healthy older subjects compared with younger ones. AB - The effect of ageing on vitamin E bioavailability in humans was assessed by comparing chylomicron and plasma alpha-tocopherol postprandial concentrations after a dose of vitamin E (432 or 937 IU as d1-alpha-tocopherol acetate), in eight young (20-30 years old) and eight healthy elderly men (64-72 years old). The fasting plasma alpha-tocopherol concentration was significantly higher in the elderly (33 +/- 2 mumol L-1) than in the young (22 +/- 2 mumol L-1). In both groups, the plasma and chylomicron alpha-tocopherol postprandial concentrations were significantly, approximately twofold, higher after the 937-IU meal than after the 432-IU meal. For both test meals, the chylomicron alpha-tocopherol areas under the curve were significantly lower in the elderly than in the young subjects: 98.9 +/- 16.5 (young group) vs. 55.3 +/- 7.8 (elderly group) mumol L-1 h for the 937-IU test meal and 60.4 +/- 14.1 (young group) vs. 26.0 +/- 7.6 (elderly group) mumol L-1 h for the 432-IU test meal, whereas the plasma alpha tocopherol area under the curve was significantly higher in elderly than in young subjects: 337.56 +/- 16.11 (937-IU test meal) vs. 159.81 +/- 35.55 (432-IU test meal) mumol L-1 h in the young group and 709.55 +/- 69.33 (937-IU test meal) vs. 436.39 +/- 41.08 (432-IU test meal) mumol L-1 h in the elderly group. We concluded that (a) the amount of vitamin E appearing in plasma is proportional to the dose ingested (up to 937 IU); (b) the intestinal absorption of vitamin E is not increased, even possibly decreased, in the elderly; and (c) the amount of vitamin E transported by non-chylomicron lipoproteins is apparently higher in the elderly. This suggests that vitamin E postprandial transport is affected by ageing, mainly as the consequence of age-related modifications of lipoprotein metabolism. PMID- 9373760 TI - Inhibition of paracrine angiotensin-converting enzyme in vivo: effects on interstitial glucose and lactate concentrations in human skeletal muscle. AB - Microdialysis was used to selectively assess the effect of the paracrine renin angiotensin system (RAS) on interstitial glucose and lactate concentration profiles in skeletal muscle of healthy volunteers (n = 8) during basal and insulin-stimulated conditions. Paracrine RAS was selectively inhibited by local retrodialysis with enalaprilate. Under basal conditions, local administration of enalaprilate (2 micrograms mL-1) increased interstitial dialysate glucose concentration from 0.71 +/- 0.14 mmol L-1 to 0.84 +/- 0.14 mmol L-1 and decreased the serum interstitial gradient (SIGglu) compared with baseline (P < 0.02). Under clamp conditions, enalaprilate, even at the lowest concentration (0.02 microgram mL-1), increased interstitial dialysate glucose concentration from 0.77 +/- 0.11 mmol L-1 to 1.02 +/- 0.09 mmol L-1 and decreased SIGglu compared with baseline (P < 0.01). Interstitial lactate concentrations slightly increased during basal as well as during clamp conditions (P < 0.05 vs. baseline). Selective inhibition of paracrine muscle angiotensin-converting enzyme (ACE) increases interstitial glucose and lactate concentrations and decreases SIGglu in muscle by facilitating transcapillary glucose transport. This effect is more pronounced during hyperinsulinaemia and may be of clinical relevance in diabetic patients treated with therapeutic doses of enalapril. PMID- 9373761 TI - Endothelial transport processes and tissue metabolism: evidence for microvascular endothelial dysfunction in insulin-resistant diseases? AB - Clinical manifestations of the insulin resistance syndrome are accompanied by endothelial dysfunction at the level of conductance and resistance vessels. Other conditions, such as smoking, also associated with endothelial dysfunction, exhibit insulin resistance too. Hypercholesterolaemia, in contrast, despite being the classical disease of endothelial dysfunction, is not associated with insulin resistance. Furthermore, only in insulin-resistant diseases, markers of microvascular alteration, such as microalbuminuria or increased plasma concentrations of von Willebrand factor, are found. At capillary sites, in contrast, transendothelial transport of both insulin and glucose takes place. These transport processes are thought to contribute to overall insulin sensitivity. In this article, I not only hypothesize but also summarize existing experimental and clinical evidence that a distinct capillary endothelial dysfunction is closely involved in the insulin resistance syndrome. PMID- 9373762 TI - Cisplatin-induced renal effects and thromboxane A2 receptor blockade. AB - The aim of this study was to evaluate the renal protective effect of linotroban, a thromboxane A2 receptor antagonist, in 25 patients with malignant tumours scheduled for cisplatin therapy. Cisplatin was administered 1 h after the start of a 24-h continuous infusion of linotroban or placebo. Glomerular filtration rate and effective renal plasma flow were measured. Infusions of cisplatin decreased glomerular filtration rate by 17 +/- 25 mL min-1 (P = 0.049 vs. baseline) and effective renal plasma flow by 94 +/- 150 mL min-1 (P = 0.049 vs. baseline) in the placebo group. In the linotroban group a decrease in glomerular filtration rate by 11 +/- 18 mL min-1 (P = 0.050 vs. baseline) and in effective renal plasma flow by 26 +/- 63 mL min-1 (P = 0.2 vs. baseline) was noted. However, no difference was noted between groups in response to treatment. Our findings indicate that linotroban may not be useful for prevention of cisplatin's acute nephrotoxic effects. PMID- 9373763 TI - Formation of black pigment gallstone in a hamster model of experimental cirrhosis. AB - The relationship between liver cirrhosis and the pathogenesis of black pigment stones has not been clarified. We attempted to induce black pigment stone formation in the gallbladders of hamsters. Male golden hamsters were divided into a cirrhosis group and a control group. Liver cirrhosis was induced by administering drinking water containing thioacetamide. The control group was given tap water. Gallstones at 48 weeks after treatment were examined by stereoscopic microscopy and scanning electron microscopy. The copper content of the black pigment stones was analysed by atomic absorption spectrophotometry. Black pigment stones in the gallbladder were detected in 25% of the cirrhosis group. Their surface and cross-section appeared amorphous. Black pigment stones contained copper. We confirmed the formation of gallstones in an animal model of cirrhosis by thioacetamide. Our findings may contribute to the clarification of the relationship between the pathogenesis of black pigment stones and the pathophysiology of liver cirrhosis. PMID- 9373764 TI - Evidence for non-adaptive immune response in HIV infection. AB - Increased levels of soluble forms of adhesion molecules such as intercellular adhesion molecule 1 (ICAM-1) and E-selectin have been found in the sera of HIV infected patients and have been associated with disease progression. The aim of the present study was to investigate whether this phenomenon reflects activation of the non-adaptive immune response in HIV infection. Fifty-one patients with HIV infection (42 men, nine women) were classified into two subgroups: those with HIV infection but without evidence of AIDS indicator conditions (HIV infected non AIDS cases, n = 27) and those with AIDS (AIDS cases, n = 24). The activation of non-adaptive immune response was evaluated as the production of reactive oxygen species that cause lipid peroxidation, which was assessed by measuring thiobarbituric reactive substances (TBARS) using the thiobarbituric acid assay (TBA). Plasma levels of von Willebrand factor (vWF), measured by rocket immunoelectrophoresis, were used to show activation of endothelial cells even in the absence of any other causative agent, in these patients. TBARS levels in non AIDS cases were significantly higher than in control subjects (n = 17) or AIDS cases (P < 0.001). The mean vWF levels were higher in AIDS cases than in non-AIDS cases or normal subjects (P < 0.05). TBARS levels remained significantly higher in non-AIDS cases after adjusting for age, CD4 T-cell and neutrophil counts, antiretroviral therapy and vWF plasma levels. The above findings indicate that in HIV infection, the virus per se is responsible for the increased oxidative stress that in turn activates various transduction pathways, may be leading to endothelial cell activation and shedding of adhesion molecules from the cell surface. PMID- 9373765 TI - Effects of endothelin-1 on circulating adhesion molecules in man. AB - Several studies point to a role for endothelin-1 (ET-1) in enhancing adhesion molecule expression and leucocyte adhesion. We thus hypothesized that ET-1 would induce expression of adhesion molecules by endothelial cells and by leucocytes in humans, and hence compared with placebo the effect of a continuous 6-h ET-1 infusion on plasma levels of circulating (c)E-selectin, cP-selectin, intercellular and vascular cell adhesion molecule 1. In addition, we investigated the effects of ET-1 on expression of the leucocyte adhesion molecules CD11b/CD18 and L-selectin on monocytes and neutrophils. After an open pilot study to evaluate the safety of a 6-h ET-1 infusion of 0.4 pmol kg-1 min-1 (n = 4), the main study was conducted as a randomized, double-blind, two-way, cross-over trial in 12 additional young healthy male volunteers, who received the same treatment and were observed over a period of 24 h. ET-1 infusion decreased renal plasma flow by 43% (CI 35-51%; P < 0.001) and increased the filtration fraction by 80% (CI 20-110%; P < 0.001). Heart rate decreased by -10% (CI -4% to -15%) at 6 h under ET-1 infusion in the cross-over trial (P = 0.012 between periods). Although ET-1 infusions increased plasma levels of ET-1 by about 300%, ET-1 elicited no relevant changes in any circulating adhesion molecules or leucocyte adhesion molecules measured. In the placebo period small diurnal changes were observed for cP-selectin (-8%, CI -14 to -3%, P = 0.008) and cE-selectin (-6%, CI -10 to -3%, P = 0.003) at 12 h (20.45 h). In sum, ET-1 does not regulate circulating adhesion molecules in healthy men. Circadian variations may exist for plasma levels of cP selectin and cE-selectin. PMID- 9373766 TI - Intestinal fatty acid-binding protein variation associated with variation in the response of plasma lipoproteins to dietary fibre. AB - Increased dietary fibre intake is a component of prudent dietary advice, although the mechanism of its beneficial effect is unclear. Furthermore, plasma lipoprotein response to dietary fibre seems to vary both between individuals and according to the type of fibre consumed. Two common genetic variants, A54 and T54, of the intestinal fatty acid-binding protein gene (FABP2) have different in vitro binding affinities for long-chain fatty acids. We have hypothesized that variation in FABP2 would be associated with interindividual variation in the response of plasma lipoproteins to either dietary soluble or insoluble fibre. We studied 43 subjects who participated in a year-long cross-over study of the effect of insoluble and soluble fibre on plasma lipoproteins. We tested for associations between FABP2 genotypes and the response of plasma lipoproteins to dietary fibre. When compared with subjects homozygous for FABP2 A54, we found that subjects with FABP2 T54 had significantly greater decreases in plasma total and low-density lipoprotein (LDL)-cholesterol and apoB during the period when the diet was high in soluble fibre than during the period when the diet was high in insoluble fibre. Furthermore, compared with subjects with the FABP2 A54 allele, subjects with the FABP2 T54 allele had significantly lower secretion of total fecal bile acids, but this did not increase with dietary soluble fibre. Genetic variation in FABP2 may thus contribute to interindividual variation in the response of plasma lipoproteins to different dietary fibres, but the mechanism does not appear to be related to increases in fecal bile acid secretion. PMID- 9373767 TI - Adult groin hernias: new insight into their biomechanical characteristics. AB - The biomechanical properties of the transversalis fascia and rectus abdominis aponeurosis were assessed in adult groin hernias, using a computerized-suction device (Cutometer) equipped with a 2-mm probe. Evaluations were made ex vivo on fresh samples collected from 63 patients with unilateral or bilateral hernias and 30 control subjects without hernias. Under 50 and 200 mbar suctions, there was no statistical difference between the overall mechanical properties of control and patient aponeuroses. For both 50 and 200 mbar suctions, the maximum distension (MD) and the biological elasticity (BE) of fasciae from direct hernias were significantly increased, compared with control fasciae. In the same comparison, the MD-50 and -200 and the BE-50 of patient fasciae from the non-herniated sides were also significantly increased. It is concluded that the presently reported biomechanical alterations seem to be the cause and not the consequence of the hernias. These data suggest that a functional connective tissue pathology probably plays a role in the genesis of groin hernias. PMID- 9373768 TI - Increased nitric oxide production in collagenous and lymphocytic colitis. AB - The production of nitric oxide (NO) is increased in active ulcerative colitis and in Crohn's disease. We have studied NO production in collagenous colitis (CC) and lymphocytic colitis (LC), both of which are inflammatory bowel disorders of unknown aetiology. NO levels were measured directly in gas sampled from the colon during colonoscopy. Plasma levels of NO metabolites (nitrate/nitrite) were also measured. Luminal NO levels were more than 100 times higher in patients with CC compared with controls. In addition, plasma levels of nitrate/nitrite were increased in the patients as compared with controls. Measurements of NO directly in the colon or its oxidation products in plasma may be a helpful tool in further understanding the role of NO in the pathophysiology of CC and LC. Moreover, it is tempting to speculate that these measurements could be clinically useful in the diagnosis and therapy monitoring of these two inflammatory bowel diseases. PMID- 9373769 TI - Thymostimulin increases natural cytotoxic activity in patients with breast cancer. AB - The effect of thymostimulin on the Natural Killer (NK) cytotoxic activity of peripheral blood mononuclear cells (PBMC) was investigated in 15 patients with breast cancer after finishing or during chemotherapy (CAF) and in 10 healthy controls. PBMC from these subjects were incubated in the presence of thymostimulin for varying periods of time (18 h or 5 days), and then used as effector cells against 51Cr-radiolabeled NK-sensitive (K-562) and NK-resistant (JY) target cells in cytotoxicity assays. No significant differences were observed between the NK-activity from breast cancer patients and healthy controls. Thymostimulin induced a dose- and time-dependent cytotoxic enhancing effect on the cytotoxic activity of PBMC from these patients against NK-sensitive K562 target cells. The thymostimulin (1000 ng/ml) significantly enhanced cytotoxic activity in PBMC from breast cancer patients who had previously received chemotherapy (p = 0.0277) against NK-sensitive cells. This increase was not statistically significant neither in PBMC from patients receiving chemotherapy nor in healthy controls (p > 0.05 in both cases). The incubation of PBMC from patients with breast cancer was not associated to a significant enhancement of the cytotoxic activity against NK-resistant target cells (p > 0.05). We also found that thymostimulin could synergize with interleukin-2 in inducing NK cytotoxic activity in PBMC after 18 h of culture (p = 0.0277). In conclusion, we have demonstrated that thymostimulin enhances the natural killer cytotoxic activity of PBMC from patients with breast cancer who have previously received chemotherapy. PMID- 9373770 TI - Immune responses of Leishmania donovani infected BALB/c mice following treatment with free and vesicular sodium stibogluconate formulations. AB - The anti-parasitic efficacy of free and a non-ionic surfactant vesicular (NIV) sodium stibogluconate (SSG) formulation of the drug, and their effect on the immune responses of Leishmania donovani infected BALB/c mice, was compared. The SSG NIV formulation maintained a significant suppression of splenic, hepatic and bone marrow parasite burdens (P < 0.005) compared to control values throughout the study. Infected controls and drug treated animals had high levels of L. donovani specific antibodies by day 14 of the study and the titre of these antibodies increased throughout the study for infected controls and free SSG treated animals. Initially SSG NIV treated animals had significantly higher specific IgG2a levels (P < 0.01, day 16) compared with infected controls and free SSG treated mice, but by day 31 the levels of this isotype and other antibodies (IgG1, IgG3 and IgM) were significantly lower (P < 0.05) than values for the other two groups. There was no difference in the proliferative responses of spleen cells taken from infected controls and drug treated animals to both specific and non-specific stimulation at day 16 of the study. On day 31, only spleen cells taken from infected mice given SSG NIV displayed a significant proliferative response to parasite antigen preparations and Concanavalin A stimulation (P < 0.01). No IL4 was detected in supernatants from in vitro spleen cells cultures. Significant levels of IFN-gamma was induced by stimulation of cells from vesicular drug treated animals with a frozen parasite preparation compared with medium controls (P < 0.05) on day 49 but not day 16. Similar stimulation did not induce IFN gamma production in spleen cells from infected controls or free drug treated animals. Only SSG NIV treated animals gave a significant positive DTH response to an L. donovani parasite preparation (P < 0.05) given on day 31. The results of this study indicate that there was a formulation dependent qualitative difference in the post-treatment immune responses of L. donovani infected animals, with SSG NIV animals displaying immune responses expected for a cured phenotype. PMID- 9373771 TI - Stimulating effect of an oral polybacterial immunomodulator on the proliferative activity of guinea pig lymphocytes. AB - A preparation for the prophylaxis and treatment of inflammations of oral mucosa and parodont Dentavax (D) was investigated in guinea pigs. Animals were given orally D for 5 consecutive days and a month later the procedure was repeated. On day 3, 10, 21, and 28 after immunization and reimmunization lymphoproliferative responses to PHA, rIL-2, LPS and D were measured by the radiometric blast transformation assay in peripheral blood, spleen, mesenteric lymph nodes (MLN) and Peyer's patches (PP). The percentage of cells entering S and G2/M-phases of cell cycle was assessed by the flow cytometric DNA analysis. A correlation in proliferative activity of cells after in vitro stimulation with PHA and LPS has been established by both methods. Peak values of lymphocyte stimulation were found on day 10, especially after the second administration of D in all organs tested, mainly in MLNs and spleen. Electron-microscopic studies demonstrated an extensive development of the endoplasmatic reticulum in plasmatic cells from spleen, PPs, mesenteric, bronchial and inguinal lymph nodes. The results obtained may be considered a proof of the immunostimulating effect of Dentavax. PMID- 9373772 TI - Antiapoptotic effect of benzyloxycarbonyl-aspartyl-(beta-tertier-butyl ester) bromomethylketone (Z-D(OtBu)-Bmk), an intermediate of interleukin-1 beta converting enzyme inhibitors. AB - The effect of several interleukin-1 beta converting enzyme (ICE) inhibitors on apoptosis was examined. The ICE inhibitors tested were peptide aldehydes such as ethyloxycarbonyl-Ala-Tyr-Val-Ala-Asp-aldehyde (Etoco-AYVAD-CHO), acetyl-Tyr-Val Ala-Asp-aldehyde (Ac-YVAD-CHO), benzyloxycarbonyl-Val-His-Asp-aldehyde (Z-VHD CHO), a tetrapeptide chloromethylketone, acetyl-Tyr-Val-Ala-Asp chloromethylketone (Ac-YVAD-Cmk) and their common intermediate benzyloxycarbonyl Asp-(beta-tertier-butyl ester)-bromomethylketone (Z-D(OtBu)-Bmk). Apoptosis was induced with several chemical agents conventionally used for this purpose in THP 1, L929, NB-41A3 cell lines and mouse thymocytes. DNA fragmentation during apoptosis was measured by conventional gel electrophoresis and ELISA. The cell morphology was examined by hematoxylin/eosin staining method. Cell viability was also monitored by MTT assay. Contrary to expectations, the peptide aldehydes listed above and Ac-YVAD-Cmk, known as highly specific ICE inhibitors, did not inhibit the apoptosis of these cell types. However, Z-D(OtBu)-Bmk, which had no relevant inhibitory activity on ICE, potently blocked the DNA fragmentation in THP-1 cells and thymocytes whichever of the inducing agents was used. In the other two cell lines Z-D(OtBu)-Bmk was inactive. The apoptotic cell morphology was also inhibited by Z-D(OtBu)-Bmk. Nevertheless, Z-D(OtBu)-Bmk failed to prevent the loss of mitochondrial activity and the cell destruction in the late phase of apoptosis. These data suggest that ICE is not involved in the apoptotic cell death induced by chemical agents. Thus, Z-D(OtBu)-Bmk, a common intermediate of some ICE inhibitors, may be a useful antiapoptotic agent for studying the early events of apoptosis in some cell types. PMID- 9373773 TI - Regulation of stress-induced reduced myelopoiesis in rats. AB - In this work we demonstrate that the stress-induced reduction in bone marrow granulocyte-macrophage colonies, reported previously from our laboratory, is prevented by both the inhibition of the hypothalamic-pituitary-adrenal axis (HPAA) and the blockage of opioid receptors. The inhibition of the HPAA was obtained through the administration of dexamethasone (1 mg/kg). The blockage of opioid receptors was done in two ways, by the administration of naltrexone (8 mg/kg) and induction of tolerance to morphine. On the other hand, no protection was observed in metyrapone treated rats. We suggest that the two physiological systems, opioid and HPAA, mediate the stress-induced myelosuppression and that these systems may function independently in this particular situation. PMID- 9373774 TI - The effect of DTC on mitogen-induced proliferation of thymocytes in restrained mice. Comparison with calf thymus extract. AB - The cardinal sign of acute stress is thymic involution, which subsequently attenuates the activity of immunocompetent cells, notably T-lymphocytes, macrophages and NK cells. Sodium diethyldithiocarbamate (DTC), a low molecular weight sulphur compound, may function as a thymic hormone to induce precursor cells to become functionally mature T-lymphocytes. The studies were conducted on Balb/c mice exposed to restraint stress twice for 12 h at 24 h intervals. DTC at a dose of 20 mg/kg or calf thymus extract (TFX) at a dose of 10 mg/kg were injected i.p. four times at 24 h intervals prior to the exposure. It has been found that restraint stress markedly reduces the number of thymocytes which is concomitant with reduction in the weight of the thymus. In our study the changes sustained for 10 days of the observation. Besides, alterations in proliferative response of the thymocytes stimulated in vitro with concanavalin A (Con A) and phytohemagglutinin (PHA) were observed. The proliferative response of thymocytes to Con A was reduced 24 h after the exposure to restraint stress, but between days 4 and 7 it was found at increased levels, which decreased again on day 10. In contrast, the proliferative response of thymocytes to PHA was depressed for the entire 10 day period of the observation. It has been found that DTC and TFX administered to mice prior to restraint stress successfully counteract stress induced immunosuppression, albeit TFX exerts stronger protective and regenerating impact on the thymus than DTC. TFX totally inhibits the suppressive effect of stress on proliferative activity of the thymocytes stimulated in vitro with Con A and PHA, stimulates restoration of thymic cells and increases the weight of the thymus. In contrast, DTC is not able to counteract the decrease in proliferative response of thymocytes to PHA. PMID- 9373775 TI - Cytokine production in saquinavir treated mice. AB - The effects of chronic and acute saquinavir treatment on murine cytokine production were investigated in both plasma and splenocyte cultures. Cytokine plasma levels were below the detection limit in both saquinavir treated mice and in control mice with the exception of IFN-gamma, whose levels were detectable in 15 day treated mice. Saquinavir was found to increase interferon gamma (IFN gamma) and interleukin-2 (IL-2) production from stimulated splenocytes. Saquinavir also caused a marked reduction of transforming growth factor-beta 1 (TGF-beta 1) in supernatants of splenocytes cultures. Conversely, interleukin-1 beta (IL-1 beta), interleukin-10 (IL-10) and tumor necrosis factor-alpha (TNF alpha) production was not modified by drug treatment. In the present paper we hypothesized that this protease inhibitor may be involved in the immunoregulatory cytokine network. PMID- 9373776 TI - Classification of factor deficiencies from coagulation assays using neural networks. AB - Activated partial thromboplastin time (APTT) and prothrombin time (PT) assays are widely used to screen for coagulation disorders and to monitor administration of therapeutic drugs. The analysis of data from coagulation assays has traditionally concentrated on determination of clot times (for APTT and PT) and magnitude of signal change during coagulation (e.g. for PT-based fibrinogen quantitation). The purpose of this study was to determine if the diagnostic power of these assays could be increased by using neural networks to interpret multiple parameters from these assays. Error back-propagation neural networks were trained using multiple variables derived from APTT and PT optical data for 200 normal and abnormal patient specimens. These networks were used to: (1) classify samples as either deficient or non-deficient with respect to individual blood components; and (2) estimate the approximate concentration of specific coagulation factors. Results indicated that these networks could be successfully trained to identify specific factor deficiencies at less than 30% normal levels with good specificity and variable sensitivity, but that they estimated actual concentrations poorly in most cases. These results support possible applications for neural networks identifying specific coagulation abnormalities from non-specific APTT and PT assays using expanded data parameter sets. PMID- 9373777 TI - A triple-head SPECT system with parallel-hole collimators of different acceptance angles. AB - We proposed to use three different parallel-hole collimators for a triple-head SPECT system. One of the collimators had a small collimator acceptance angle to provide ultra-high spatial resolution and the other two had larger collimator acceptance angles to achieve high counts. A new 2D reconstruction algorithm that combined the data acquired from different collimators was derived to take advantages of both high resolution and high sensitivity. The algorithm was evaluated using a computer-simulated matrix of spherical sources. For noise-free data, the accuracy (mainly determined by spatial resolution) obtained from combination of the collimator acceptance angles of 1.35, 4.05 and 6.75 degrees (or 1.35, 5.40 and 9.45 degrees) was slightly inferior to that obtained from three same LEHR collimators (with a 2.70 degrees collimator acceptance angle). This is because the modulation transfer function (MTF) resulting from three different collimators decreases more quickly at low frequencies but becomes comparable at high frequencies as compared with the MTF of the 2.70 degrees collimator. With noisy data, however, the image quality obtained with three different collimators was better than that resulting from any combinations of three same collimators. The improvement was only achieved by using the derived algorithm, while the conventional FBP algorithm did not improve image quality even with the same collimator configuration. PMID- 9373778 TI - Design, construction and evaluation of systems to predict risk in obstetrics. AB - We present a systematic, practical approach to developing risk prediction systems, suitable for use with large databases of medical information. An important part of this approach is a novel feature selection algorithm which uses the area under the receiver operating characteristic (ROC) curve to measure the expected discriminative power of different sets of predictor variables. We describe this algorithm and use it to select variables to predict risk of a specific adverse pregnancy outcome: failure to progress in labour. Neural network, logistic regression and hierarchical Bayesian risk prediction models are constructed, all of which achieve close to the limit of performance attainable on this prediction task. We show that better prediction performance requires more discriminative clinical information rather than improved modelling techniques. It is also shown that better diagnostic criteria in clinical records would greatly assist the development of systems to predict risk in pregnancy. PMID- 9373779 TI - Power spectral analysis of EEG in a multiple-bedroom, multiple-polygraph sleep laboratory. AB - OBJECTIVES: We describe the methods for power spectral analysis (PSA) of sleep electroencephalogram (EEG) data at a large clinical and research sleep laboratory. The multiple-bedroom, multiple-polygraph design of the sleep laboratory poses unique challenges for the quantitative analysis of the data. This paper focuses on the steps taken to ensure that our PSA results are not biased by the particular bedroom or polygraph from which the data were acquired. METHODS: After describing the data acquisition system hardware, we present our signal amplitude calibration procedure and our methods for performing PSA. We validate the amplitude calibration procedure in several experiments using PSA to establish tolerances for data acquisition from multiple bedrooms and polygraphs. RESULTS: Since it is not possible to acquire identical digitized versions of an EEG signal using different sets of equipment, the best that can be achieved is data acquisition that is polygraph-independent within a known tolerance. We are able to demonstrate a tolerance in signal amplitude of +/- 0.25% when digitizing data from different bedrooms. When different data acquisition hardware is used, the power tolerance is approximately +/- 3% for frequencies from 1 to 35 Hz. The power tolerance is between +/- 3 and +/- 7% for frequencies below 1 Hz and frequencies between 35 and 50 Hz. Additional data demonstrate that variability due to the hardware system is small relative to the inherent variability of the sleep EEG. CONCLUSION: The PSA results obtained in one location can be replicated elsewhere (subject to known tolerances) only if the data acquisition system and PSA method are adequately specified. PMID- 9373780 TI - Angiocardiographic digital still images compressed via irreversible methods: concepts and experiments. AB - We defined, implemented and tested two new methods for irreversible compression of angiocardiographic still images: brightness error limitation (BEL) and pseudo gradient adaptive brightness and contrast error limitation (PABCEL). The scan path used to compress the digital images is based on the Peano-Hilbert plane filling curve. The compression methods limit, for each pixel, the brightness errors introduced when approximating the original image (i.e. the difference between the values of corresponding pixels as grey levels). Additional limitations are imposed to the contrast error observed when considering along the scan path consecutive pixels of both the original and the reconstructed image. After previous testing on angiocardiographic images selected as clinically significant from 35 mm films, we enlarged our experiment to a set of 38 coronary angiograms digitally acquired. BEL and PABCEL methods were experimented according to several values of the implied thresholds. Up to a compression ratio of 9:1 for the BEL method and 10:1 for the PABCEL method, no deterioration of the reconstructed images were detected by human observers. After a visual evaluation, we performed a quantitative evaluation. The visualization of pseudo-colour difference images showed the capability of BEL and PABCEL for preserving the most significant clinical details of the original images. For comparison, we applied the JPEG (joint photographic experts group) image-compression standard to the same set of images. In this case, pseudo-colour difference images showed a homogeneous distribution of errors on the image surface. Quantitative compression results obtained by testing the different methods are comparable, but, unlike JPEG, BEL and PABCEL methods allow the user to keep under his direct control the maximum error allowed at each single pixel of the original image. These different behaviors are confirmed by the values obtained for the considered numerical quality quantifiers. PMID- 9373781 TI - The Porto meetings on adrenergic mechanisms. PMID- 9373782 TI - Chronic terbutaline treatment desensitizes beta-adrenergic inhibition of lymphocyte activation in healthy volunteers. AB - 1. A substantial body of evidence has accumulated that beta-adrenoceptor mediated increases in human lymphocyte cyclic AMP can inhibit activation of resting lymphocytes. The aim of this study was to determine whether this effect might desensitize during chronic beta-adrenoceptor agonist treatment. We assessed the effects of 2 weeks treatment with the beta 2-adrenoceptor agonist terbutaline (3 x 5 mg day-1 p.o.) on isoprenaline-induced inhibition of concanavalin A-evoked lymphocyte activation in nine healthy male volunteers. Lymphocyte activation was determined by [3H]-thymidine incorporation (as a measure of proliferation), and inositol phosphate formation was assessed in [3H]-myo-inositol prelabelled lymphocytes in the presence of 10 mM LiCl. 2. Terbutaline treatment caused a significant reduction in isoprenaline (1 nM-10 microM)-induced increases in lymphocyte cyclic AMP content; the maximal increase was 14 +/- 3 pmol/10(6) cells before and 7 +/- 2 pmol/10(6) cells (n = 9, P < 0.05) after terbutaline treatment. 3. The mitogen concanavalin A (Con A, 1-32 micrograms ml-1)-induced increase in inositol phosphate formation was significantly enhanced after terbutaline treatment (max. increase before treatment: 255 +/- 25% above basal; after treatment 453 +/- 16% above basal; n = 9, P < 0.001), while isoprenaline (1 nM-10 microM)-induced inhibition of Con A (16 micrograms ml-1)-evoked increases in inositol phosphate formation was significantly reduced after the terbutaline treatment (max. inhibition before treatment: 22 +/- 4%; after treatment 9 +/- 1%, n = 9, P < 0.01). 4. Con A (1.25-10 micrograms ml-1)-induced increases in [3H] thymidine incorporation into the lymphocytes (as a measure of proliferation) was not affected by the terbutaline treatment. On the other hand, isoprenaline (1 nM 1 microM)-induced inhibition of Con A (5 micrograms ml-1)-evoked lymphocyte proliferation (max. inhibition: 33 +/- 7%, n = 9) was almost completely abolished after the terbutaline treatment. 5. We conclude that chronic treatment with terbutaline desensitizes lymphocyte beta 2-adrenoceptors and, therefore, the inhibitory effect of cyclic AMP on lymphocyte activation. PMID- 9373783 TI - Prevention by a somatostatin analogue of the hypertensive and cardiovascular structural changes induced by blockade of adenosine receptors. AB - 1. Long-term administration of the adenosine receptor antagonist, 1,3-dipropyl-8 sulfophenylxanthine (DPSPX), causes arterial hypertension and cardiovascular hypertrophic and hyperplastic changes (Matias, Albino-Teixeira, Polonia & Azevedo, 1991). As somatostatin is a repressor of cell growth, and adenosine is a potent inducer of the somatostatin gene, we investigated the putative involvement of somatostatin in the cardiovascular effects of DPSPX. 2. DPSPX (90 micrograms kg-1 h-1, i.p.) or saline and the somatostatin analogue, octreotide (75 micrograms kg-1 day-1, s.c.), or saline were infused through Alzet minipumps to Wistar rats. Blood pressure was measured with the tail-cuff technique. Seven days after implantation of the minipumps the rats were killed and the tissues prepared for microscopy. 3. DPSPX induced arterial hypertension and cardiovascular hypertrophic and hyperplastic changes as previously described (Matias et al., 1991). Treatment of the rats with octreotide alone had no effect either on blood pressure or in blood vessel morphology. However, octreotide prevented both the hypertensive and the cardiovascular morphologic effects of DPSPX. 4. The results are compatible with the involvement of somatostatin in the long-term cardiovascular effects of adenosine. PMID- 9373784 TI - DMPP-evoked increases in postganglionic sympathetic nerve activity and blood pressure occurs by two mechanisms in the rat. AB - 1. Intravenous administration of the ganglionic nicotinic receptor agonist DMPP (1,1-dimethyl-4-phenylpiperazinium iodide) into urethane-anaesthetized rats evoked dose-dependent increases in mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA). 2. The ganglionic nicotinic receptor antagonists pentolinium and hexamethonium either alone or combined did not inhibit the increase in RSNA and MAP evoked by 50 to 200 micrograms kg-1 doses of DMPP. The increase in renal sympathetic nerve activity evoked by DMPP occurred as a brief burst in firing. 3. The increase in MAP, but not RSNA, evoked by DMPP in the presence of pentolinium was inhibited by the selective alpha 1-adrenergic receptor antagonist prazosin. 4. The non-selective alpha-adrenoceptor and NPY receptor antagonist benextramine also inhibited the increase in MAP without inhibiting the increase in RSNA. Surprisingly, the combination of benextramine and pentolinium, or benextramine and hexamethonium, completely blocked the DMPP evoked increase in RSNA and thus the increase in MAP. 5. The uptake1 antagonist desipramine combined with pentolinium did not affect the DMPP-evoked increases in MAP or RSNA when compared to the responses evoked in the presence of pentolinium alone. 6. Adding the selective M1 muscarinic receptor antagonist telenzepine to pentolinium and prazosin did not inhibit the increase in RSNA evoked by a 100 micrograms kg-1 dose of DMPP. 7. While the DMPP-evoked increase in MAP in the presence of ganglionic nicotinic receptor antagonists is primarily dependent upon activation of alpha 1-adrenoceptors, the increase in RSNA occurs via activation of ganglionic nicotinic receptors and activation of a mechanism susceptible to blockade by benextramine. PMID- 9373785 TI - Use of [3H]-clozapine as a ligand of the dopamine D4 receptor subtype in peripheral tissues. AB - 1. Molecular biology studies have documented the presence of peripheral dopamine D4 receptors. This site has not been characterized yet with classical radioligand binding assay techniques because of the lack of selective radioligands. 2. The atypical neuroleptic clozapine labelled with tritium ([3H]-clozapine) has been proposed and sold as a radioligand for brain dopamine D4 receptors. However, the selectivity of [3H]-clozapine for D4 receptor subtypes, and its specificity for brain dopamine receptors, have been questioned. 3. In this study dopamine D4 receptors were assayed in peripheral organs known to express them, such as rat atria and kidney, by using a radioligand binding assay technique with [3H] clozapine as the radioligand. Parallel experiments were performed using Chinese hamster ovary (CHO) cells transfected with the D4 receptor clone (variant D4.2). 4. [3H]-Clozapine was bound to sections of rat atria and kidney. After appropriate blockade of sites other than dopamine receptors to which it can bind (i.e. muscarinic cholinergic, serotonergic and alpha-adrenergic receptors), the radioligand was bound to a site displaying a pharmacological profile similar to that expressed by CHO cells transfected with the D4 receptor. 5. The above findings indicate that with appropriate protocols, [3H]-clozapine may represent a radioligand for peripheral dopamine D4 receptors. PMID- 9373786 TI - Rational choice of an oral beta-lactam antibiotic. PMID- 9373787 TI - A closer look at vancomycin, teicoplanin, and antimicrobial resistance. AB - The worldwide increase in the incidence of resistant Gram-positive infections has renewed interest in the glycopeptide class of antimicrobial agents. Two glycopeptides are available in many parts of the world--vancomycin and teicoplanin. These two agents appear to differ in several respects, including: potential for selecting microbial resistance, dosing convenience, safety, and efficacy in severe infection. Teicoplanin appears to have lower toxicity and greater convenience; however, its widespread acceptance has been plagued by concerns over antimicrobial resistance, efficacy, and appropriate dosing. A review of available studies suggests that teicoplanin, when dosed at 6 mg/kg/day, is better tolerated than vancomycin 15 mg/kg/q12h; however, at these doses, it appears to be somewhat less effective than vancomycin in serious Staphylococcus aureus infection, such as endocarditis. Although higher doses of teicoplanin, 12 mg/kg/day to 30 mg/kg/day, have been associated with efficacy comparable to that of vancomycin in serious S. aureus infections, such doses may eliminate some of the safety advantages conferred by lower teicoplanin doses. Teicoplanin has been associated with resistance among coagulase-negative staphylococci and the selection of resistance in S. aureus. There is some evidence that widespread use of teicoplanin might accelerate the development of S. aureus resistance to both teicoplanin and vancomycin. The selection of an appropriate glycopeptide in an individual patient should be based not only on convenience, but also on a determination of optimal efficacy, safety at an efficacious dose, and the potential for resistance. PMID- 9373789 TI - Comparative in vitro activity of cefepime against nosocomial isolates. AB - Cefepime, a new parenteral cephalosporin, was evaluated for its in vitro antibacterial activity in comparison with other broad-spectrum antibiotics against a total of 445 recently isolated microorganisms of nosocomial origin. Cefepime was highly active against all species of Enterobacteriaceae with minimum inhibitory concentrations (MIC90S) ranging from 0.25-8 micrograms/ml. Cefepime showed moderate activity against Acinetobacter spp (MIC50 and MIC90, 16 micrograms/ml) but its activity was superior to that of any drug tested, except imipenem. Against Pseudomonas aeruginosa its activity was comparable to that of ceftazidime and was greater than that of cefotaxime, aztreonam, ciprofloxacin and aminoglycosides. Of all the agents tested, imipenem was the most active compound. Cefepime was active against Staphylococcus aureus and coagulase-negative methicillin-susceptible staphylococci but it had no activity against methicillin resistant staphylococci and enterococci. PMID- 9373788 TI - Comparative in vitro evaluation of piperacillin/tazobactam in a tertiary care hospital. AB - Bacterial resistance is usually a serious problem in tertiary care hospitals. The aim of this in vitro study was to evaluate the beta-lactamase inhibitor combination piperacillin/tazobactam in a hospital environment with high bacterial resistance rates and compare it with other beta-lactam agents. Three hundred and sixty-two isolates from various clinical materials were studied during the period March-August 1996. Material for culture was collected from patients of all the wards of our hospital, with the majority being from the Intensive Care Unit (45%). Pathogenic Gram-positive and Gram-negative bacteria with high resistance rates and beta-lactamase production were studied (staphylococci, enterococci, Enterobacteriaceae, Pseudomonas). Significant bacterial resistance rates were identified for ceftazidime (50% for Klebsiellae, 60% for Enterobacter spp, 60% for Proteus spp, 33% for Pseudomonas spp, 75% for Acinetobacter spp) and ciprofloxacin (33% for both Klebsiellae and Enterobacter spp, 67% for Pseudomonas spp, 50% Acinetobacter spp). Fifty percent of Enterococcus isolates were resistance to ciprofloxacin but all of them were susceptible to piperacillin/tazobactam, amoxicillin/clavulanate and imipenem. The antibacterial activity of piperacillin/tazobactam (susceptibility rates 83 to 100% for Enterobacteriaceae, 83% for Pseudomonas spp and 75% for Acinetobacter spp) was higher than that of ceftazidime, piperacillin and ciprofloxacin. Imipenem, being mostly a reserve product, showed higher activity against Acinetobacter, Klebsiella and Enterobacter species. PMID- 9373790 TI - Treatment for advanced hepatocellular carcinoma by transarterial chemotherapy using reservoirs or one-shot arterial chemotherapy. AB - A prospective trial was performed in patients with advanced hepatocellular carcinoma to assess the therapeutic efficacy of transcatheter arterial chemotherapy using implanted reservoirs (12 patients) or conventional transcatheter arterial chemotherapy (8 patients). Epirubicin at a dose of 40 mg/m2 was given every month in the former, while epirubicin at a dose of 60 mg/m2 was administered every 3 months in the latter. During the 6 months from the introduction of these therapies, hospitalized periods were shorter and total hospital costs were less in the reservoir group than in the conventional chemotherapy group (p < 0.05 and p < 0.01, respectively). Transcatheter arterial chemotherapy using implanted reservoirs can be carried out on a day-care basis and may be beneficial for the treatment of patients with advanced hepatocellular carcinoma. PMID- 9373791 TI - Prognostic factors in patients with localized Ewing's sarcoma: the effect on survival of actual received drug dose intensity and of histologic response to induction therapy. AB - To bring to the fore the most important prognostic factors in Ewing's sarcoma (ES) with current protocols, we studied the classical prognostic factors, dose intensity (DI) of actual received drugs, age and histological response to induction therapy and their correlation in 39 patients with localized ES treated from 11/85 to 06/95 to identify eventual predictors of event-free survival (EFS). Inclusion criteria were age 35 yr or less, definitive local treatment by our team and chemotherapy including at least 4 drugs: vincristine (VCR), dactinomycin (DACT), doxorubicin (DOXO) cyclophosphamide (CPX). The endpoint was the absence of relapse. Parameters related to the status of patients were tested using the Chi square test or Fisher's exact test. The non parametric Kruskal-Wallis test was used for quantitative data. When necessary stratified analysis was done using the Mantel Cox test. With a median follow-up of 7 yr, overall survival (OS) and EFS were both 67% at 7 yr. According to univariate analysis, the significant predictors of survival were the DI of VCR and DACT, the histological response to preoperative chemotherapy (CT), the patient's age (< 18 yr DFS: 84%; > 18 yr DFS: 38%). The risk of metastases was almost tenfold higher in patients with low received DI of VCR (DFS 40% versus 95%) and of DACT (DFS 48% versus 94%). The prognostic value of primary tumor characteristics (tumoral volume or location) was erased by the comprehensive treatment. Following multivariate analysis, the actual received DI of VCR (p < 0.02) and DACT (p < 0.03) and the histological response to preoperative CT (p < 0.05) were retained as the only significant independent predictors of EFS. Taking into account the actual received DI of VCR and DACT, the prognostic value of age disappears. In conclusion, this study points out the main role of the drug DI in ES (particularly VCR and DACT) and of histological response to preoperative CT. PMID- 9373792 TI - A two-step reevaluation of high-dose amsacrine for advanced carcinoma of the upper aerodigestive tract: a pilot phase II study. AB - Results of amsacrine studies in different solid tumors with a dose of 85 mg/m2/24 h x 1 quo 3 weeks have been, in general, disappointing. Although only a few patients with head and neck cancer have been included in broad phase II studies, several responses have been reported, but detailed data concerning responders are lacking. In the present study, amsacrine (Amsidil, Godecke-Parke Davis) was administered at an increased dose of 85 mg/m2/24 h x 3 (total dose per cycle 255 mg/m2) quo 3-4 weeks. 25 patients with advanced carcinoma of meso and hypopharynx were included in the first step of this phase II study (11/25 with histological grades I/II and 14/25 with histological grades III/IV; 10/25 pretreated with radical radiotherapy and 15/25 previously untreated), and 5 patients with undifferentiated carcinoma of the nasopharyngeal type (UCNT), all previously treated. 5/30 patients achieved a complete response (CR) and 5/30 a partial response (PR), the overall response rate being 10/30. Regarding the histology grade, only 1/11 patients with grade I/II carcinoma of meso and hypopharynx achieved a PR with no CR, but 5/14 with grade III/IV from the same group achieved a CR. Out of 10 pretreated patients only one achieved any response and none of the 5 patients with UCNT. Thus, in the second step of this study, high dose amsacrine was evaluated in the target group of previously untreated patients with advanced grade III/IV carcinoma of meso and hypopharynx. 20 patients were included in the second step and all were evaluable for activity. A CR was achieved for 6/20 patients and a PR for 7/20 patients (response rate 65%, 95% confidence interval 44%-86%). Hematological toxicity from both steps included grade IV granulocytopenia in 25/50 patients (50%, 95% confidence interval 36% 64%) and grade IV thrombocytopenia in 18/50 patients (36%, 95% confidence interval 23%-49%). High dose amsacrine seems to be a toxic, but very effective drug as first-line treatment for poorly differentiated carcinoma of meso and hypopharynx, and further studies seem warranted. PMID- 9373793 TI - Allogeneic peripheral blood stem cell transplantation: is there an increased risk of graft vs host disease in leukemia patients? AB - Fifteen patients with hematological malignancies [9 acute nonlymphoblastic leukemia (ANLL), four chronic myelogenous leukemia (CML), two acute lymphoblastic leukemia (ALL)] received allogeneic peripheral blood stem cell transplantation (alloPBSCT) from HLA-identical sibling donors. Donors received 2.5-15 micrograms/kg/day of recombinant human granulocyte colony stimulating factor (rhG CSF) for 5-10 days. Administration of rhG-CSF was well tolerated except for mild to moderate bone pain occurring in all the donors which was relieved by oral paracetamol. A total of 40 leukaphereses were performed for the 15 donors using the bilateral antecubital veins. None of the donors needed central venous line insertion. The median number of apheresis procedures for each patient was 3 (2 3). A median of 7.7 (4-38.2) x 10(8)/kg mononuclear cells, 35 (2.4-90.0) x 10(6)/kg CD34+ cells, 1.85 (0.45-4.8) x 10(8)/kg CD3 and 0.3 (0.16-1.01) x 10(8)/kg natural killer cells were given without any manipulation. Cyclosporin A (CsA) plus short-course methotrexate (MTX) (12 patients) and CsA alone (3 patients) were used for graft versus host disease (GVHD) prophylaxis. Median granulocyte and platelet engraftments were done on days 11 (10-31) and 16 (11-54) respectively. Grades II-IV GVHD occurred in 62% of the patients and grades III-IV in 15%. Twelve patients are still alive with full engraftment and disease-free. In conclusion, alloPBSCT is an alternative to allogeneic bone marrow transplantation, because of the ease of collection and rapid hematological recovery. However, there is a trend for increased acute GVHD in our leukemia patients compared to allogeneic bone marrow. PMID- 9373794 TI - Effect of high-dose medroxyprogesterone acetate on tumor necrosis factor-alpha release in patients with chemotherapy-induced neutropenia. AB - The aim of the study was to investigate the effects of high-dose medroxyprogesterone acetate (MPA) on the tumor necrosis factor-alpha (TNF-alpha) release in patients with chemotherapy-induced neutropenia. We also evaluated the effects of high-dose MPA on hematological parameters (leukocyte, neutrophil, platelet, hemoglobin, hematocrit) and side effects of MPA. One week following the first cycle chemotherapy, 20 patients who developed neutropenia were enrolled in the study. One gram/day MPA was administered orally to the patients and was continued from one week following the first chemotherapy cycle to one week after the second chemotherapy cycle. The patients received the second chemotherapy cycle at the same dosages as the first cycle. Before MPA treatment TNF-alpha levels were lower than post-treatment levels, but the difference was not statistically significant (P > 0.05). The differences in the mean leukocyte and neutrophil counts before and after the high-dose MPA treatment were statistically significant (p < 0.05). PMID- 9373795 TI - Effect of granulocyte-macrophage colony-stimulating factor on prevention of mucositis in head and neck cancer patients treated with chemo-radiotherapy. AB - Twenty-nine previously untreated patients with squamous cell carcinoma of the oral cavity and pharynx underwent a treatment program with four courses of chemotherapy alternated with three courses of radiotherapy. Granulocyte macrophage colony-stimulating factor (GM-CSF) was administered at a dose of 5 micrograms/mg subcutaneously on the same day as radiation treatment in order to prevent mucositis. No grade 4 mucositis was reported; only four episodes of grade 2 mucositis and thirteen grade 2. Comparing these results with historical patients treated with the same chemotherapy-radiation program but without GM-CSF, the authors concluded that GM-CSF is an effective treatment for preventing mucositis produced by chemotherapeutic and/or radiotherapeutic interventions in patients at high risk of oropharyngeal mucosal damage. PMID- 9373796 TI - Glucose metabolism in the human cerebellum: an analysis of crossed cerebellar diaschisis in children with unilateral cerebral injury. AB - Using high-resolution positron emission tomography (PET), we have recently described the normal pattern of glucose utilization in 11 anatomical regions of the human cerebellum. In the present study, we evaluated the phenomenon of crossed cerebellar diaschisis in 40 patients (mostly children) with unilateral cerebral injury sustained at various periods of brain development. Diaschisis refers to a functional impairment at a remote site following injury to an anatomically connected area of brain and, presumably due to a loss of afferent input to the remote site. Of the 40 patients, 11 had sustained their cerebral injury prenatally, 7 in the perinatal period (+/- 24 hours of birth), and 22 postnatally (1 day to 15 years). Crossed cerebellar hypometabolism was seen in 22 patients; symmetric cerebellar metabolism was found in 16 subjects. The presence of crossed cerebellar hypometabolism was typically associated (75% of cases) with a postnatal injury, while symmetric cerebellar metabolism was seen only in patients with injury occurring prior to 4 weeks of age (13 of the 16 had prenatal or perinatal insults). A third pattern of cerebellar metabolism, consisting of paradoxical crossed cerebellar hypermetabolism, was seen in two patients; both had sustained their cerebral injury at 4 months of age. These findings suggest the presence of considerable plasticity, which is dependent on age at injury, in the cerebrocerebellar pathway of developing brain. PMID- 9373797 TI - Clinical antecedents of neurologic and audiologic abnormalities in survivors of neonatal extracorporeal membrane oxygenation. AB - Extracorporeal membrane oxygenation is an effective rescue treatment for severe cardiorespiratory failure in term or near term neonates, although cerebral palsy, mental retardation, and sensorineural hearing loss are observed in 10 to 20% of survivors. The objective of the present study was to identify potential risk factors that may explain the neurologic and audiologic sequelae noted in 19% of 181 survivors of neonatal extracorporeal membrane oxygenation from our hospital. Our results suggest the following findings in survivors of severe cardiorespiratory failure treated with neonatal extracorporeal membrane oxygenation: (1) hypotension or the need for cardiopulmonary resuscitation before extracorporeal membrane oxygenation significantly increases the risk of spastic cerebral palsy, (2) profound hypocarbia before extracorporeal membrane oxygenation is associated with a significantly increased risk of hearing loss, (3) mental retardation in the absence of spastic cerebral palsy is unexplained except when due to abnormal fetal brain development, and (4) hypoxemia in the absence of hypotension does not increase the risk of neurologic or audiologic sequelae. PMID- 9373798 TI - "Joubert syndrome" revisited: key ocular motor signs with magnetic resonance imaging correlation. AB - Joubert syndrome is characterized by episodic hyperpnea and apnea, developmental delay, hypotonia, truncal ataxia, ophthalmologic abnormalities, and vermian dysgenesis. We studied 15 patients with the diagnosis of Joubert syndrome to (1) more fully define the syndrome's clinical features, and (2) correlate the clinical features with magnetic resonance imaging (MRI) findings. Eight of 15 patients had a history of episodic hyperpnea and apnea. All patients had developmental delay and hypotonia. Of the 13 patients receiving detailed neuro ophthalmologic evaluations, three had optic nerve dysplasia, pendular nystagmus, and gaze-holding nystagmus. All 13 patients had a normal vestibulo-ocular reflex based on head thrust, but had absent to poor ability to cancel the vestibulo ocular reflex horizontally and vertically. Twelve of 13 patients had impaired smooth pursuit. Twelve of 13 patients had defects in initiation of saccades and quick phases. Two of the most consistent radiologic features were absent or hypoplastic posterior cerebellar vermis, and deformed midbrain and pontomesencephalic junction, which based on ocular motor physiology correlate with the vestibulo-ocular reflex cancellation/ pursuit defect and saccade initiation defect, respectively. As a result of midbrain, vermian, and superior cerebellar peduncle abnormalities, axial neuroimaging showed a unique "molar tooth" appearance of these structures. These results indicate that Joubert syndrome results from maldevelopment of the midbrain and cerebellar vermis, producing a pathognomonic sign on MRI. PMID- 9373799 TI - Language and motor functions activate calcified hemisphere in patients with Sturge-Weber syndrome: a positron emission tomography study. AB - This study examines whether or not in Sturge-Weber syndrome hypoperfused brain areas that are affected by calcification continue to retain some function and participate in language and motor activations. [15O]-Water positron emission tomography (PET) was used for brain mapping of these functions in two patients with extensive unilateral calcification and hypoperfusion and in one patient with calcification and hypoperfusion restricted to the left posterior region. Task related regional cerebral blood flow changes suggest that (1) hypoperfused areas may become activated during language and motor performance, and (2) progressive calcification in Sturge-Weber syndrome is associated with functional reorganization in the language and motor domains. Interhemispheric reorganization appears to be more pronounced for language than for motor functions. PMID- 9373800 TI - Neuromotor functioning in children with Tourette syndrome with and without attention deficit hyperactivity disorder. AB - Neuromotor function was assessed in 94 children of normal intelligence with Tourette syndrome, Tourette syndrome and attention-deficit hyperactivity disorder (ADHD), or ADHD only, using the Physical and Neurological Examination of Subtle Signs (PANESS). Time to complete six motor movements was analyzed separately by side (left and right) and complexity (simple and patterned). All groups performed faster on their preferred, dominant side. Although all groups took longer to complete patterned versus simple movements, the group with ADHD had a larger discrepancy for complexity than the other two groups. The speed for simple and patterned tasks was at or faster than age expectations for 54% of tasks in the group with Tourette syndrome but only 15% of tasks in the other two groups. More children in the group with Tourette syndrome (76%) than the groups with Tourette syndrome with ADHD (54%) or ADHD (54%) or ADHD only (65%) performed movements within normal time limits for age. Findings suggest that Tourette syndrome is not associated with motor slowing. PMID- 9373801 TI - Vitamin D levels in noninstitutionalized children with cerebral palsy. AB - Calcitriol (1,25-dihydroxy vitamin D) is an important hormone in calcium and phosphate metabolism. Levels of calcitriol and its precursor, 25-hydroxy vitamin D (calcidiol), were measured in a heterogeneous group of 125 noninstitutionalized children and adolescents with spastic cerebral palsy. Levels of each were correlated with: (1) clinical factors including mobility, prior fracture, and use of anticonvulsants; (2) nutrition and growth parameters including skinfolds, body mass index, and use of vitamin supplements; and (3) other serum analyses including osteocalcin as a marker of bone formation, calcium, and alkaline phosphatase. Levels of calcidiol and calcitriol did not correlate with any of the various clinical, nutritional, or growth parameters examined. The prevalence of low (< 10 ng/mL) levels of calcidiol was significant (19%), and dependent on the season of the year in which the level was measured. In contrast, less than 2% of the patients were found to have a low (< 20 pg/mL) level of calcitriol and the mean was comparable to normal pediatric subjects. Levels of calcitriol are maintained in noninstitutionalized children with cerebral palsy despite anticonvulsants, poor nutrition, and calcidiol levels that vary greatly with the seasons. PMID- 9373802 TI - Acute hemorrhagic leukoencephalitis: recovery and reversal of magnetic resonance imaging findings in a child. AB - A case of acute hemorrhagic leukoencephalitis (AHLE) in a 6-year-old girl is reported. The presentation was typical for acute hemorrhagic leukoencephalitis, with acute onset of a rapidly progressive neurologic disorder with asymmetric involvement of brain, with polymorphonuclear predominant peripheral leukocytosis and cerebrospinal fluid pleocytosis. Cerebrospinal fluid findings not previously reported included elevation of IgG and the presence of myelin basic protein. Additional previously unreported findings were striking abnormalities on magnetic resonance imaging (MRI) of the brain, in contrast to normal findings on computed tomography (CT). The child was treated with high dose intravenous steroids and made a full recovery, with a parallel disappearance of all of her cerebrospinal fluid abnormalities and almost all of her abnormalities on MRI. Detailed examination of cerebrospinal fluid and MRI of brain should facilitate early diagnosis in other cases of suspected acute hemorrhagic leukoencephalitis and high-dose steroid therapy may lead to improved clinical outcomes. PMID- 9373803 TI - Use of the Modified Mini-Mental State Examination with children. AB - The validity and reliability of the modified version of the Mini-Mental State Examination with children was examined. The Modified Mini-Mental State Examination was administered to 99 children between 4 and 12 years of age (45 males and 54 females) to assess expected scores for nonclinical children and with a clinical sample. Concurrent validity was assessed through correlations of Modified Mini-Mental State Examination scores with Wechsler Intelligence scores and Child Behavior Checklist scores. The Modified Mini-Mental State Examination was administered to 26 children on two occasions to determine test-retest reliability. Means and standard deviations of scores are reported by age and grade level. Test-retest reliability coefficients were positively significant. For the nonclinical sample, Modified Mini-Mental State Examination scores were significantly and positively correlated with Verbal IQ and Child Behavior Checklist scores. Modified Mini-Mental State Examination scores were significantly correlated with Verbal IQ scores in the total and clinical samples. PMID- 9373804 TI - Asymptomatic hyperammonemia in children treated with valproic acid. PMID- 9373805 TI - Childhood AIDS, varicella zoster, and cerebral vasculopathy. PMID- 9373806 TI - Felbamate for refractory infantile spasms. PMID- 9373807 TI - Do codeine and caffeine enhance the analgesic effect of aspirin?--A systematic overview. AB - OBJECTIVE: To assess whether codeine and caffeine enhance the analgesic effect of aspirin in post-operative pain. METHOD: Systematic overview of the literature and meta-analysis of published randomized controlled trials (RCTs). RESULTS: Codeine 60 mg leads to a small increase in the analgesic effect of 650 mg of aspirin when total pain relief score (TOTPAR%) is used as a efficacy end-point. This increased effect was not seen when sum of pain intensity (SPID%) and proportions of patients responding with moderate to excellent pain relief were used as outcome measures. Caffeine did not enhance the analgesic effect of aspirin. CONCLUSION: Codeine 60 mg may produce a small increase in the analgesic effect of aspirin 650 mg. However, this effect is not clinically meaningful. Caffeine has no adjuvant analgesic effect. At over-the-counter (OTC) doses, caffeine and codeine are not useful in aspirin formulations. PMID- 9373808 TI - Non-pharmacological modification of cardiac risk factors: Part 2. The role of diet. AB - A high intake of saturated fats and cholesterol is associated with an increased risk of developing and dying from coronary artery disease (CHD), particularly if other risk factors are present. However, although a reduction in the consumption of the amounts of saturated fat and cholesterol may reduce the incidence of primary and secondary CHD in susceptible individuals, other dietary measures may also be important. These include an increased consumption of poly- and monounsaturated fatty acids, fresh fruit, fish and fibre. PMID- 9373809 TI - Therapeutic advances: protease inhibitors for the treatment of HIV-1 infection. AB - BACKGROUND: Anti-retroviral treatment of human immunodeficiency virus (HIV) infection is undergoing great changes, brought about by a better understanding of the disease pathology. One of the most recent advances has been the introduction of the protease inhibitors, reversible inhibitors of HIV aspartic protease. Published data on the clinical efficacy of these drugs are limited, but preliminary results suggest that, in combination with one or more nucleoside analogues, they represent an important advance in the treatment of patients with advanced HIV infection. The adverse effects and potential for drug interactions, together with the additional cost associated with prescribing these drugs, mean that careful selection and supervision of these patients is imperative. AIM: To present an up-to-date review of the three most recently introduced protease inhibitors. METHODS: Based on a review of the literature, abstracts from relevant meetings and information from the pharmaceutical companies. CONTENT: A review including background data on HIV infection and the treatment options. Detailed information on ritonavir, saquinavir and indinavir. CONCLUSIONS: These new drugs are useful additions to the therapeutic current aims for the treatment of HIV infection. They need to be used under close supervision by specialists. PMID- 9373810 TI - Investigation of urinary levels of salbutamol in asthmatic patients receiving inhaled therapy. AB - AIM: Some studies have indicated that over-reliance on inhaled bronchodilator (beta 2-agonist) therapy may worsen asthma control and increase morbidity. The aim of this study was to measure urinary concentrations of salbutamol, the most commonly used bronchodilator, in a relatively large sample of asthmatic patients and examine the potential value of the concentration as an indicator of over-use of salbutamol. METHOD: The urinary concentrations of the drug were measured in 'spot' urine samples from 102 asthmatic patients (64 community patients and 38 hospital inpatients). A solid-phase extraction technique, using a phenyl-bonded phase and a reversed-phase ion-pair high-performance liquid chromatography assay with UV-detection were developed and used to measure both unchanged salbutamol concentrations and total salbutamol concentrations after enzymatic hydrolysis of the metabolite. In addition, salbutamol concentrations were corrected for urine dilution, with the measured drug expressed per gram of urinary creatinine. RESULTS: The hospital patients were generally older, had greater disease severity, were more likely to be receiving prophylactic therapy and had received more salbutamol in the past 24 h. The urinary concentrations of salbutamol varied enormously between patients. The median concentrations of unchanged and total drug were 0.38 microgram/ml (range 0-34.4 micrograms/ml) and 2.55 micrograms/ml (range 0-49.8 micrograms/ml), respectively. Even when controlling for dosage in the preceding 24 h, there was a 262-fold and 810-fold variation in the urinary concentrations for unchanged and total salbutamol, respectively, among the community patients. Modest correlations were found between salbutamol concentrations and dosage administered in the preceding 24 h (Spearman's r = 0.67 and 0.54 for unchanged and total drug, respectively; P < 0.001). The correlations improved only slightly with correction for urine dilution (Spearman's r = 0.69 and 0.57 for unchanged and total drug, respectively; P < 0.001). CONCLUSION: This enormous inter-patient variability, which may be largely due to differences in the pharmacokinetics of salbutamol and inhaler technique, may play a role in the observed worsening of asthma control with the regular use of inhaled bronchodilator drugs and warrants further investigation. Measuring urinary concentrations of salbutamol in spot samples provides only a relatively crude indication of the extent of use of inhaled salbutamol in the preceding 24 h. PMID- 9373811 TI - Comparative evaluation of patient information leaflets by pharmacists, doctors and the general public. AB - This study was undertaken to compare and contrast the views of pharmacists, general practitioners (GPs) and the general public on the value or otherwise of pharmacy-generated patient information leaflets. All three groups perceived these leaflets to be useful and an aid to improving compliance. Concerning the information included in leaflets, GPs rated the inclusion of a section on side effects as being the least important, whilst pharmacists and the general public rated information on the storage of medicines as being least important. Pharmacists' estimates on what percentage of patients actually read leaflets were significantly lower than estimates by the general public. General practitioners and pharmacists generally concurred on the types of patients for whom leaflets are considered unsuitable, although a significantly higher percentage of pharmacists than GPs identified unsuitable patients. There were reservations by the pharmacists concerning the cost-effectiveness of leaflet facilities and on the value of leaflets compared with verbal counselling. The general public expressed the view that a leaflet facility would affect their choice of pharmacy and that they would be prepared to wait an additional short time to receive such a leaflet. Almost all GPs thought that it was in the patient's best interest to receive an information leaflet. PMID- 9373812 TI - Study of the correlation between MEIA and ELISA methods for FK 506 determination in liver transplant recipients. AB - BACKGROUND AND OBJECTIVES: FK 506 is an immunosuppressive macrolide advocated for prevention of graft rejection. Plasma or blood FK 506 levels must be determined to strike a balance between FK 506 toxicity and graft rejection. The first aim of this study was to compare an automated microparticle enzyme immunosorbent assay (MEIA) method (on whole blood) with the reference enzyme-linked immunosorbent assay (ELISA) method (on plasma). A second aim was to compare the two methods for prediction of FK 506 nephrotoxicity. PATIENTS AND METHODS: Forty-seven patients were studied comprising 128 samples. All were treated with FK 506 on a compassionate basis. For each patient, the concentrations of FK 506 were determined in plasma by means of ELISA and in whole blood by MEIA. RESULTS: The repeatability and the reproducibility of these two methods were similar. The inter-patient correlation coefficient between MEIA and ELISA, determined on 128 samples from 47 liver recipients, was satisfactory (r = 0.82). From these 47 patients, the intra-patient correlation coefficients were calculated for 17 of them. The intra-patient correlation coefficients were between 0.63 and 0.98 for 15 patients, and between 0.26 and 0.55 in the remaining two cases. Mean creatinine plasma levels in the 55 samples below the median FK 506 value in the MEIA method and in the 55 with values above the median (120 and 134 mumol/litre, respectively) were significantly different (P < 0.05), as were those using the reference ELISA methods (115 and 139 mumol/litre, P < 0.01). In contrast, there was no significant difference between the mean creatinine plasma levels in the 55 samples with FK 506 levels below the median using both methods or between those above the median. CONCLUSION: The automated MEIA method, being simpler and more rapid than the ELISA method, should now be preferred for therapeutic monitoring of FK 506. PMID- 9373813 TI - Comparison of the disposition kinetics of lidocaine and (+/-)prilocaine in 20 patients undergoing intravenous regional anaesthesia during day case surgery. AB - OBJECTIVE: The aim of this investigation was to compare the pharmacokinetics of lidocaine and prilocaine in two groups of 10 patients undergoing intravenous regional anaesthesia. METHOD: The study had a randomized design. The patients were allocated to one of the two groups of 10. Each group received either lidocaine (200 mg = 0.855 mM) or prilocaine (Citanest, 200 mg = 0.909 mM), injected intravenously over a period of 30 s. Onset of the surgical analgesia was defined as the period from the end of the injection of the local anaesthetic to the loss of pinprick sensation in the distribution of all three nerves. RESULTS: The mean onset time of surgical analgesia of lidocaine was 11.2 +/- 5.1 min and that of prilocaine was 10.9 +/- 6.0 min. After releasing the tourniquet, lidocaine is bi-exponentially eliminated with a t1/2 alpha of 4.3 +/- 2.1 min and a t1/2 beta of 79.1 +/- 31.2 min. Total body clearance was 0.86 +/- 0.39 litres/min. Prilocaine is rapidly and bi-exponentially eliminated with a t1/2 alpha of 3.0 +/- 1.6 min and a t1/2 beta of 29.9 +/- 15.7 min. The total body clearance of prilocaine is higher than that of lidocaine, 4.15 +/- 1.31 vs. 0.86 +/- 0.39 litres/min, respectively (P = 0.0007). Both compounds show comparable volumes of distribution (Vd, Vss and V beta) and a comparable t1/2 alpha (4.3 +/- 2.1 vs. 3.0 +/- 1.6 min; P = 0.1780). The t1/2 beta for the two compounds were different (P = 0031); 79.1 +/- 31.2 min for lidocaine and 29.9 +/- 15.7 min for prilocaine. The mean residence time (MRT) of lidocaine (193 +/- 233 min) also differed significantly from that of prilocaine (33.4 +/- 19.9 min; P = 0.0022). CONCLUSION: Lidocaine is preferred for relatively long procedures and prilocaine for short procedures. PMID- 9373814 TI - Improving the prescribing of antibiotics for urinary tract infection. AB - BACKGROUND: In recent years there have been changes in the recommended antibiotic treatment for urinary tract infections (UTIs). In particular, the use of amoxycillin or co-trimoxazole is now discouraged, with amoxycillin-potassium clavulanate, cephalexin and trimethoprim becoming first-line agents for uncomplicated lower UTIs. AIM: To examine whether academic detailing, performed by a pharmacist, could modify prescribing practices for antibiotics used in the treatment of UTI in the community setting. METHODS: The intervention was conducted in Southern Tasmania, using the remainder of the State as a control area. The target group of general practitioners was sent educational material designed to assist in the appropriate prescribing of antibiotics in the treatment of UTI. A pharmacist then visited each general practitioner and discussed the rational use of antibiotics for UTIs directly with him/her. Outcomes were measured using evaluation feedback from the general practitioners and pharmacoepidemiological data, which were not linked to diagnosis. The key variable examined was the total defined daily doses (DDDs) dispensed for the recommended first-line agents (amoxycillin-potassium clavulanate, cephalexin and trimethoprim) compared with amoxycillin (3 g single-dose form) and co trimoxazole. RESULTS: The educational programme was very well received by the general practitioners. Changes in the prescribing of antibiotics commonly used for UTIs were evident in both study regions over the course of the study, but the improvements were significantly greater in the intervention area. CONCLUSION: Educational programmes utilizing academic detailing by pharmacists can modify prescribing practices within the community setting. PMID- 9373815 TI - Primary health care for people with an intellectual disability. PMID- 9373816 TI - Primary health care and people with an intellectual disability: the evidence base. AB - There is growing awareness of the importance of evidence-based medicine in guiding health care delivery. This paper reviews the evidence pertinent to the delivery of primary health care to people with an intellectual disability. Research concerning issues of health status, specialist knowledge of health care, and barriers and solutions to health care delivery for people with an intellectual disability is presented and discussed. Recommendations for future evidence-based research are made, including suggested areas of importance. PMID- 9373817 TI - People with intellectual disability in general practice: case definition and case finding. AB - In a general practice database containing data on 62,000 patients, those with intellectual disability (ID) were traced. Health problems in this database were recorded according to the International Classification of Health Problems in Primary Care (ICPC) code. By using selected codes, 318 people with ID (0.65% of the study population) were found; the sample contained nearly as many false positives. Adding up the percentage of people with ID living in residential facilities, the total prevalence of people with ID was estimated as 0.82%. Documentation on the cause and level of ID was available in about half of the cases. The demographic characteristics of the people with ID were significantly different from the general population: there was a higher percentage of males and a lower percentage of people over 50 years of age among those with ID. Information about the use of home care was virtually non-existent in the general practice data. The results are compared with those of other studies. The discussion deals with reasons for complete documentation of cases with ID in general practice and the role of the general practitioner in health care supply to people with ID. PMID- 9373818 TI - The general practice care of people with intellectual disability: barriers and solutions. AB - A questionnaire exploring general practitioners' (GPs') perceptions of the barriers and solutions to providing health care to people with intellectual disability was sent to 912 randomly selected GPs throughout Australia. A response rate of 58% was obtained. Results indicated that numerous barriers compromise the quality of health care able to be provided to people with intellectual disability. Communication difficulties with patients and other health professionals, and problems in obtaining patient histories stood out as the two most significant barriers. A range of other barriers were identified, including GPs' lack of training and experience, patients' poor compliance with management plans, consultation time constraints, difficulties in problem determination, examination difficulties, poor continuity of care, and GPs' inadequate knowledge of the services and resources available. General practitioners also suggested numerous solutions to these barriers, and emphasized the need for increased opportunities for education and training in intellectual disability. The GPs showed an overwhelming willingness to be involved in further education. Other major solutions included increasing consultation duration or frequency, proactively involving families and carers in patients' ongoing health care, and increasing remuneration. PMID- 9373819 TI - Attitudes of general practitioners towards health care for people with intellectual disability and the factors underlying these attitudes. AB - An intellectual disability attitude questionnaire was used to explore the attitudes of general practitioners (GPs) towards primary health care, organizing health promotion and the role of specialist services for people with intellectual disability. The results of this questionnaire from GPs in Gwent (Wales) and GPs in west Gloucestershire (England) were compared. The GPs in both areas responded similarly and tended to agree that they were responsible for the medical care of people with intellectual disability in the community. They also tended to feel that the move from hospitals to the community of people with intellectual disability would greatly increase their workload. The GPs in both areas were generally against a responsibility on their part for health promotion and health screening initiatives for people with intellectual disability. However, GPs in west Gloucestershire felt more strongly against these issues. Further analysis of the data revealed factors which influenced the response of GPs to the questionnaire, including their position regarding health promotion and screening, and their view of the role of specialist health services. The GPs generally felt that community learning disability teams provided useful support, and there is clearly scope for team members to liaise more closely with GP practices and to provide helpful information to GPs about intellectual disability and the specialist health services available. Professionals seeking to work collaboratively with GPs should be sensitive to their workload pressures and to their attitudes towards health promotion initiatives and health screening. PMID- 9373820 TI - Health gain through health checks: improving access to primary health care for people with intellectual disability. AB - People with intellectual disability were identified through the local register and through liaison with general practitioners (GPs). A consultation exercise was conducted with users and carers to ascertain their experiences and perspectives of primary health care (GP services). A comprehensive health check was devised and administered to about 120 people to detect physical disorders, especially cardiovascular risk factors. A standardized checklist was used to determine the population of people with psychological and psychiatric problems. Case notes were reviewed after nearly one year to determine physical and psychological health gain. Significant gains were noted with regard to physical disorders. In contrast, mental health problems were underreported and participants had achieved few gains on follow-up. The reasons and implications for future service planning are discussed. PMID- 9373821 TI - A randomized control trial of an opportunistic health screening tool in primary care for people with intellectual disability. AB - People with intellectual disability have an increased variety of health care problems compared with the general population. The transition of care for such people from institutions into the community places them in a primary care system already facing increasing demands for their services. There is a consensus that health screening is at its most useful in identifying functional disabilities. Therefore, an intervention which helps the general practitioner (GP) towards opportunistically checking those areas of health most often deficient in people with intellectual disability would appear of considerable benefit (especially if information directing the GP towards appropriate secondary care services is also provided). The present study was designed to evaluate the impact of such an intervention. PMID- 9373822 TI - The importance of smoking education and preventative health strategies for people with intellectual disability. AB - Tobacco smoking is a major health problem within our community. To date, little attention has been focused on determining the prevalence of smoking in people with disabilities or in developing appropriate strategies to assist them to stop smoking. Funding from the Victorian Health Promotion Foundation enabled the Developmental Disability Unit at Monash University, Box Hill, Victoria, Australia, to undertake a project investigating smoking in a population of people with intellectual disability. In the first part of the project, the smoking rate among a geographically defined group of people with mild intellectual disability was investigated. A smoking prevalence of 36% was found within the sample group, as compared to a prevalence of 26% within the general Victorian adult population. An association was found between the motivation to quite and the recall of advice to stop smoking. The second part of the project comprised the development and piloting of a smoking education course for people with intellectual disability. The pilot sample was small, but the results were encouraging. Fifty-five per cent of the group either quit smoking or cut down their intake significantly. Seventy three per cent expressed a desire to stop smoking at the completion of the course, and all participants expressed an increased concern and knowledge about the effects of smoking on their health after completing the course. PMID- 9373823 TI - Diagnosis of sensory impairment in people with intellectual disability in general practice. AB - The present authors have participated in the development of a Dutch consensus on the early detection, diagnosis and treatment of hearing and visual impairment in children and adults with intellectual disability. They argue that the early detection of sensory impairment in babies and children with intellectual disability should primarily be a responsibility of paediatricians and youth health physicians. General practitioners should be aware of the necessity of screening and should check whether this has been done when children visit the surgery. It is stressed that the general practitioner should play a more active role in the detection of age-related sensory loss in older adults with intellectual disability, and the assessment of younger adults whose sensory functions have never or incompletely been evaluated. Annual sensory screening is certainly not necessary, but annual otoscopy to detect impacted earwax or unidentified middle ear infection, as well as checks of the proper use of glasses and hearing aids, are suggested. Most adults with mild or moderate intellectual disability can be assessed with methods that are normally used by general practitioners. Uncooperative people should be referred for screening with specialized methods. A low-threshold referral system (e.g. via district expert teams) has been outlined. PMID- 9373824 TI - Nutritional support for patients with intellectual disability and nutrition/dysphagia disorders in community care. AB - Patients with intellectual disability and neurological handicaps associated with swallowing difficulties are vulnerable to dehydration and undernutrition. Some patients are severely undernourished, a condition which is usually associated with recurrent food aspiration and respiratory infections. Underweight patients are usually provided with adequate dietary protein by carers: their low energy intakes reflect inadequate intakes of fat and carbohydrate. Many patients gain weight following the provision of easily assimilated energy-dense fat- and sugar containing foods. Where these measures fail, the provision of a percutaneous endoscopic gastrostomy (PEG) tube may be life-saving. Optimal supervision of patients with severe nutrition/dysphagia problems requires a support network linking carers at home or in community care facilities with the primary health care team and the local district general hospital. PMID- 9373825 TI - Twenty years and still in the dark? Content analysis of articles pertaining to gay, lesbian, and bisexual issues in marriage and family therapy journals. AB - To what extent do marriage and family therapy journals address gay, lesbian, and bisexual issues and how does this coverage compare to allied fields? To answer these questions, a content analysis was conducted on articles published in the marriage and family therapy literature from 1975 to 1995. Of the 13,217 articles examined in 17 journals, only 77 (.006%) focused on gay, lesbian, and/or bisexual issues or used sexual orientation as a variable. Findings support the contention that gay, lesbian, and bisexual issues are ignored by marriage and family therapy researchers and scholars. PMID- 9373826 TI - The National Marital and Family Therapy Examination Program. AB - Examinations constitute one of the principal methods by which professions assess minimal competence in aspiring practitioners. The Examination in Marital and Family Therapy is used by most states which regulate the profession. This article provides the rationale for the examination program, describes its development and maintenance, and presents the knowledge base it samples. Administrative policies and procedures are also discussed as an aid to prospective licensure and certification candidates. PMID- 9373827 TI - Positive practice in family therapy. AB - Positive practice, a brief integrative approach to consultation with families, is described in this paper. A clear distinction is made between the stages of planning, assessment, therapy, and disengagement. Guidelines for progression from one stage to the next are provided. Frameworks for deciding who to invite to preliminary sessions and methods for planning and organizing lines of inquiry are incorporated into this approach to practice. A three-column model is used to construct formulations. The model allows therapists and clients to map information about the pattern of interaction around the presenting problem, beliefs that constrain family members from altering their roles in these problem maintaining patterns, and factors that have predisposed family members to hold these beliefs. Positive practice offers methods for evolving new behavioral patterns and belief systems within sessions and for arranging homework tasks for clients between sessions. It also incorporates methods for dealing with resistance, for managing therapeutic crises, for convening individual sessions and broader network meetings, for disengaging from the consultation process, and for recontracting for further episodes of therapy. This evolving approach to practice draws on ideas from many traditions within the family therapy field and takes account of recent research relevant to the practice of family therapy. PMID- 9373829 TI - Just in love. PMID- 9373828 TI - Thinking about romantic/erotic love. AB - The implications for therapy of the salient characteristics of romantic/erotic love are discussed. 1. We do not have control over our feelings of romantic/erotic love. 2. These feelings occur relatively infrequently during most people's lives. 3. Being with a partner whom one loves is valued and regarded as a good; it sometimes conflicts with other values and goods. There are no clear criteria for resolving this conflict. 4. Love is regarded as one essential basis for marriage. 5. In addition to romantic/erotic love, other qualities and capacities are important in sustaining a long-term relationship such as a marriage. PMID- 9373830 TI - Examining the multifaceted notion of isomorphism in marriage and family therapy supervision: a quest for conceptual clarity. AB - The notion of isomorphism has been recommended as a conceptual framework to guide the practice of marriage and family therapy (MFT) supervision. The term is frequently cited in the MFT training literature but is often used in different ways. A panel of MFT supervisors rated the importance and relevance to both therapy and supervision of a large pool of variables. The majority of variables were found to be equally relevant or isomorphic to the domains of MFT and MFT supervision. A qualitative interview with a small subset of the panelists suggested that the concept, to varying degrees, has influenced their work as supervisors. The implications of the results for theory development, research and supervisory practice are discussed. PMID- 9373831 TI - Gender-related therapist attributions in couples therapy: a preliminary multiple case study investigation. AB - Differential treatment by gender has been an ongoing area of concern and uncertainty both in society at large and in clinical research. In this investigation, therapist attributions over the course of therapy for three different couples were coded and analyzed to determine if cause for positive and negative events was assigned differentially to females and males. Additionally, the stability and globality dimensions of the therapist's attributions about the couples were examined for stereotypical gender-related patterns. Results indicate no gender differences in locus of causal attributions but some gender-related patterns in stability and globality dimensions. Implications for both couples therapy and gender bias in couples research are discussed. PMID- 9373832 TI - Differential assessment of financial and relationship distress: implications for couples therapy. AB - This study examined the role of financial conflicts, problem-solving communication deficits, and global relationship distress among couples in marital therapy and couples seeking assistance at a nonprofit agency providing financial counseling services. Analyses comparing these two groups of couples with each other and with a third group of couples from the general community yielded a two component model for differential assessment and intervention with couples experiencing financial concerns. Differences in findings for husbands and wives provided additional implications for effective interventions with these couples. PMID- 9373833 TI - Challenges stepfamilies face. PMID- 9373835 TI - Perinatal-neonatal medicine: trends for the future? PMID- 9373836 TI - Pulse oximetry in infants of < 1500 gm birth weight on supplemental oxygen: a national survey. AB - OBJECTIVE: To determine practices related to the use of pulse oximetry in monitoring infants of < 1500 gm birth weight on supplemental oxygen. STUDY DESIGN: A mailing list of all neonatal intensive care units with accredited Neonatal-Perinatal Fellowship programs was prepared. A questionnaire was prepared and mailed to collect information on the following: Method used for noninvasive monitoring of oxygen therapy, acceptable maximum and minimum arterial pulse oxygen saturation levels, high and low alarm settings, and whether oxygen was administered at a fixed or variable rate. RESULTS: A response rate of 70% to 85% was achieved for different items of the questionnaire. A wide variation exists regarding acceptable arterial pulse oxygen saturation levels and alarm settings. Many units accepted an arterial pulse oxygen saturation level of 100% or set the high alarm at 100%. CONCLUSION: There is a need for greater awareness of the potential for hyperoxemia that may result from accepting an arterial pulse oxygen saturation level of 100% or setting high alarms at 100%. We urge stricter adherence to published recommendations. PMID- 9373837 TI - A comparison of birth weight and weight/length ratio for gestation as correlates of perinatal morbidity. AB - OBJECTIVE: The purpose was to evaluate a low weight to length ratio as a correlate of perinatal morbidity and mortality. STUDY DESIGN: Data from the Collaborative Perinatal Project for infants of 34 weeks' gestation or more were evaluated. Associations between the weight to length ratio of < 10% (low weight to length) and birth weight of < 10% (small for gestational age) by gestational age and gender, perinatal depression, dysmaturity, cerebral palsy, and neonatal mortality were evaluated. RESULTS: A low weight to length ratio and small for gestational age status were associated with most markers of perinatal morbidity and mortality in term and preterm infants. In infants not small for gestational age, a low weight to length ratio was associated with increased morbidity and mortality (relative risk of 1.9 to 4.2) in term infants, and with perinatal depression (relative risk of 2.9) in preterm infants. Logistic regression found low weight to length ratio was a better independent correlate than small for gestational age status for all markers assessed and found low weight to length ratio was significantly associated with all morbidity and mortality markers in infants not small for gestational age. CONCLUSION: Low weight to length ratio, a marker for asymmetric growth restriction, is correlated with perinatal morbidity, even in infants not small for gestational age. PMID- 9373838 TI - Noise analysis of three newborn infant isolettes. AB - OBJECTIVE: The purpose of this study was to evaluate the noise of three newborn infant isolettes. STUDY DESIGN: An observational, prospective study evaluated noise in three isolettes (Ohmeda, Air Shields, and Drager). The study measured interior isolette noise production during quiet noise situations and isolette noise attenuation of added low- and high-frequency noise. Noise was measured on the decibel A scale and in the 125 Hz and 1000 Hz bands. RESULTS: During quiet conditions the Ohmeda and Drager isolettes had the least noise production on the basis of decibel A levels (p < 0.001). Low-frequency noise on the decibel A scale was attenuated the most by the Drager isolette (p < 0.001), although the overall difference may be clinically insignificant. The Ohmeda isolette attenuated high frequency noise by 28.4 dB as measured on the decibel A scale, which was greater than values for the Drager (22.8 dB) and Air Shields (14 dB) isolettes (p < 0.001). CONCLUSIONS: High-frequency noise attenuation by the Ohmeda and Drager isolettes is clinically and statistically greater than high-frequency noise attenuation by the Air Shields isolette. PMID- 9373839 TI - Is Clostridium difficile a pathogen in the newborn intensive care unit? A prospective evaluation. AB - OBJECTIVES: The purpose of this study was to investigate (1) the presence of Clostridium difficile toxin in patients in the newborn intensive care unit and (2) the association of C. difficile toxin with gastrointestinal tract symptoms in this population. STUDY DESIGN: A prospective, masked study was done in which twice-weekly stool specimens of subjects hospitalized in a newborn intensive care unit during a 4-month period were analyzed for C. difficile toxin A by enzyme immunoassay. Daily data collection included infant clinical status, stool frequency and character, presence of gastrointestinal tract symptoms, and actions taken for gastrointestinal tract symptoms. Infants hospitalized 5 or more days who had at least two stool assays comprised the study population. For data analysis, an infant with C. difficile toxin-positive status was defined as an infant with two or more toxin-positive stools. RESULTS: Of 87 infants who met study criteria, 42 (48%) had toxin-negative and 45 (52%) toxin-positive results on at least one specimen. Of the infants with toxin-positive findings, 27 (31%) had two or more positive stool assays and comprised the comparison group. The infants with toxin-positive results were smaller, less mature, and had a longer hospital stay than infants with toxin-negative results (p < 0.001). Infants with toxin-positive findings had more days per infant with frequent (> 6) stools and abnormal stools (p < 0.001). The total number of symptom days was 8.2 +/- 5.7 in infants in the toxin-positive group versus 2.2 +/- 2.2 in those in the toxin negative group (p < 0.001). The mean number of times stools were sent for evaluation and culture was greater in infants with toxin-positive findings (p < or = 0.012) whereas there was no difference in the number of times oral feedings were withheld from infants or infants had abdominal films obtained (p > or = 0.18). CONCLUSIONS: Infants hospitalized in our newborn intensive care unit frequently had stools positive for C. difficile toxin A. When compared with infants with toxin-negative findings, infants with colonization had an increased number of days with gastrointestinal tract symptoms. PMID- 9373840 TI - Bronchoalveolar lavage in ventilated newborn infants: safety and tumor necrosis factor-alpha activity. AB - OBJECTIVE: To investigate the safety of bronchoalveolar lavage (BAL) in sick ventilated preterm and term newborn infants. STUDY DESIGN: We studied 32 preterm and term newborn infants on mechanical ventilation during the first week of life. BAL was done through blind wedging of a suction catheter into the right lower lobe bronchus, and lavages were tested for albumin content and tumor necrosis factor-alpha (TNF-alpha) activity. Safety measures included cranial ultrasounds, chest radiographs, arterial pH and blood gas monitoring, and checking ventilatory settings before and up to 24 hours after the procedure and heart rate, oxygen saturation level and arterial blood pressure before, during and within 10 minutes after the procedure. RESULTS: Heart rate dropped an average of 15% (p < 0.001), oxygen saturation decreased by 4% (p = 0.001), and systolic blood pressure increased by 19% (p < 0.001) during BAL, but these measures returned to baseline on completion of the procedure and were not outside of a physiologically accepted range. BAL did not result in neonatal morbidity or mortality. Blood pressure perturbations were of a lesser magnitude in infants with a birth weight < 1000 gm than in those > 1000 gm. The lavage fluid contained albumin, and TNF-alpha titers were generally low except in two very preterm infants with extensive intracranial hemorrhages and one preterm infant with sepsis from chorioamnionitis. CONCLUSION: BAL can be safely performed in intubated preterm and term infants, and the lavage samples are useful for cytokine assays. PMID- 9373841 TI - Impact of new treatments for neonatal pulmonary hypertension on extracorporeal membrane oxygenation use and outcome. AB - OBJECTIVE: To determine the impact of new treatment modalities, including high frequency oscillatory ventilation (HFOV) and inhaled nitric oxide (INO), on extracorporeal membrane oxygenation (ECMO) use and outcome of neonatal patients with persistent pulmonary hypertension of the newborn. STUDY DESIGN: We reviewed the medical records of neonatal patients meeting established ECMO criteria from 1988 to 1995. Clinical data were gathered from this retrospective chart review. Comparison of ECMO experiences were made between the 1988-90 period (pre-HFOV and INO, or period 1) and the 1993-95 period (HFOV and INO fully established as treatment modalities, or period 2). RESULTS: One hundred three patients were treated with ECMO during the 8-year study period. After HFOV and INO were introduced in 1991 and 1992 respectively, the number of patients meeting established ECMO criteria who subsequently required ECMO therapy progressively declined, from 22.3 +/- 2.3 (mean +/- SD) patients per year during period 1 to 12 patients in 1991 when HFOV was introduced, 8 patients in 1992 when INO was introduced, and 5.3 +/- 2.9 patients per year in period 2. The number of patients referred for ECMO over time did not change. Survival after ECMO dropped from 84% during period 1 to 56% in period 2. Introduction of new pre-ECMO therapies has not delayed institution of ECMO, significantly increased the length of ECMO runs, or lengthened the hospital course of ECMO survivors. A comparison of the eight infants treated with ECMO in 1992 with the 10 infants treated with INO in 1993 showed a longer hospital stay and a larger average patient bill for the patients treated with ECMO. CONCLUSION: New treatment approaches for severe persistent pulmonary hypertension have reduced ECMO use, shortened the duration of hospitalization, and reduced costs for those infants responding to HFOV and INO. However, survival of patients requiring ECMO therapy has decreased. PMID- 9373842 TI - Umbilical cord thiocyanate and thyroid function in intrauterine growth-restricted infants of the smoking gravida. AB - OBJECTIVE: We evaluated maternal and umbilical cord thiocyanate and thyroid function in intrauterine growth-restricted infants of smoking mothers. STUDY DESIGN: One hundred six mother-infant pairs were studied and divided into four groups: smokers with appropriate for gestational age infants (n = 37), smokers with intrauterine growth-restricted infants (n = 19), nonsmokers with appropriate for gestational age infants (n = 33), and nonsmokers with intrauterine growth restricted infants (n = 17). Sera from mothers were analyzed for thiocyanate levels. Serum from umbilical cord blood was analyzed for thiocyanate, thyroxine, resin triiodothyronine uptake, and thyroid-stimulating hormone. The free thyroxine index was then calculated. RESULTS: A significant correlation was found between maternal and umbilical cord thiocyanate levels (r = 0.90, p < 0.0001). Maternal and umbilical cord thiocyanate concentrations correlated with increased maternal cigarette use. For appropriate for gestational age and intrauterine growth-restricted infants, mean maternal and umbilical cord thiocyanate levels were not significantly different. The umbilical cord thiocyanate level did not correlate with thyroid function or birth weight. The umbilical cord thyroxine level was lower in nonsmokers than in smokers. CONCLUSION: Thiocyanate was not more concentrated in the intrauterine growth-restricted infant and did not correlate with thyroid function or birth weight. The thyroxine level was decreased significantly in intrauterine growth-restricted infants born to nonsmoking mothers. Further studies are necessary to evaluate the effects of smoking on thyroid function and on fetal growth and development. PMID- 9373843 TI - Association between the severity of chronic lung disease and first-year outcomes of very low birth weight infants. AB - OBJECTIVE: The objective of this study was to determine if there is an association between the severity of chronic lung disease in very low birth weight infants (as assessed by the duration of supplemental oxygen requirements in the neonatal period) and first-year neurodevelopmental, sensory, and growth outcomes as well as duration of neonatal hospitalization and first-year hospital readmissions. STUDY DESIGN: Retrospective chart review with matched subject groups. METHODS: The subjects of this study were very low birth weight infants born between 1987 and 1991 in a 17-county perinatal region of North Carolina. Infants were categorized into one of three groups on the basis of duration of supplemental oxygen requirements. Infants who were breathing room air by 28 days were classified as having no chronic lung disease; infants who required supplemental oxygen at 28 days but not at 36 weeks postmenstrual age were classified as having mild chronic lung disease; and infants who required supplemental oxygen at 36 weeks postmenstrual age were classified as having severe chronic lung disease. Infants were matched for birth weight, sex, and race. The matched groups (n = 174) were compared with respect to the incidence of first year adverse neurodevelopmental and sensory outcomes, growth patterns, and hospital readmissions during the first year. Results were analyzed with general linear models and logistic regression analyses. RESULTS: The incidence of any adverse neurodevelopmental or sensory outcome increased as severity of chronic lung disease increased from none (3.6%) to mild (21.4%) to severe (31.6%, p < 0.001). Growth patterns were similar in infants with no and mild chronic lung disease, but infants with severe chronic lung disease were significantly lighter (p < 0.01) and shorter (p < 0.005) at 40 weeks postmenstrual age and significantly lighter at 1 year adjusted age (p < 0.05). The duration of the initial hospitalization increased with chronic lung disease severity (p < 0.001). Infants with severe chronic lung disease were readmitted to the hospital significantly more often (p < 0.005) than infants with no chronic lung disease or mild chronic lung disease. CONCLUSIONS: Very low birth weight infants who required supplemental oxygen at or beyond 28 days were at increased risk for adverse neurodevelopmental and sensory outcomes, but only those infants who continued to require supplemental oxygen at 36 weeks were at increased risk for poor growth and readmission to the hospital. PMID- 9373845 TI - Postnatal inositol levels in preterm infants. AB - OBJECTIVE: To measure plasma inositol levels in preterm infants fed formula containing inositol at levels close to those in human milk. STUDY DESIGN: Plasma inositol levels were measured in 72 preterm infants fed formula containing 1110 mumol/L inositol and in cord blood of 12 healthy term infants. Preterm infant plasma levels were measured four times: (1) within the first 7 days of life, (2) intermediate enteral feeding, (3) at hospital discharge, and (4) 2 months after hospital discharge. RESULTS: Inositol concentrations in term cord blood samples were significantly lower than in preterm initial feeding, intermediate feeding, and discharge samples. Initial concentrations in blood of preterm infants were higher than in all other groups, and were significantly lower among infants with gestational ages of 31 to 33 weeks compared with those of 28 to 30 or 31 to 33 weeks. Days of parenteral nutrition were a significant predictor of inositol levels in the full feeding sample, with lower levels associated with prolonged parenteral nutrition. Clinical outcomes were not related to plasma inositol levels. CONCLUSIONS: Feeding preterm formula with inositol levels close to those reported for human milk may not prevent the postnatal decline in preterm infant plasma inositol levels. PMID- 9373846 TI - Incongruence between nurses' and parents' perceptions of nurses' caring behaviors in a neonatal intensive care unit. AB - The primary purpose of this study was to test an instrument designed to assess nurses' caring behaviors in a neonatal intensive care unit, the setting for the study. The convenience sample (n = 88) was 42 nurses who worked in a neonatal intensive care unit and 46 parents whose infants were hospitalized there. The Wilcoxon two-sample rank-sum test was used to test the difference in ranking of the 15 items (nurses' caring behaviors) between the nurses and parents. There was agreement on the most caring behavior, "The nurses understood my need to touch my baby and encouraged me to do so" and the least caring behavior, "The nurses did not know the sex of my child." However, a significant difference was found between the nurses and parents on 4 of the 15 behaviors. The findings serve to sensitize the clinicians to their caring behaviors by heightening their awareness of how caring behaviors are perceived by parents. PMID- 9373844 TI - Alteration of normal gastric flora in neonates receiving ranitidine. AB - OBJECTIVES: To determine if the administration of ranitidine to neonates leads to an increase in gastric pH to > or = 4 and if this increase in gastric pH correlates with gastric colonization. STUDY DESIGN: 628 pH measurements and 276 gastric cultures were obtained from 86 neonates. Twenty-three patients received ranitidine and 63 patients served as controls. RESULTS: Treated patients had a mean gastric pH of 5.6 compared with a control mean pH of 4.4 (p < 0.0001). Gastric pH was significantly affected by feeding and postnatal age. 54 patients were colonized with pathogenic bacteria and/or yeast (n = 20 treated, n = 34 control). Length of hospitalization (p < 0.0001), increase in gastric pH (p < 0.01), days of antibiotics before culture (p < 0.0001), and ranitidine use (p < 0.0001) were associated with an increased rate of colonization. CONCLUSIONS: The use of ranitidine did lead to a significant increase in gastric pH and with this increase in gastric pH gastric colonization rates increased. No increased frequency of infection was found in ranitidine-treated infants. PMID- 9373847 TI - Water beds may be useful in preventing scaphocephaly in preterm very low birth weight neonates. PMID- 9373848 TI - The Mead Johnson Nutritionals Perinatal Research Conferences: a thirty-four-year trek from Aspen to both coasts. PMID- 9373849 TI - Diagnosis of ductus arteriosus aneurysm by magnetic resonance imaging. PMID- 9373850 TI - Jarcho-Levin syndrome: prenatal diagnosis, perinatal care, and follow-up of siblings. AB - Jarcho-Levin syndrome (JLS), spondylothoracic or spondylocostal dysostosis, is a rare entity with variable clinical severity. This syndrome is usually diagnosed in individuals with short neck, short trunk, and short stature with multiple vertebral anomalies at all levels of the vertebral column, including "butterfly vertebrae," hemivertebrae, and fused, hypoplastic vertebrae. The small size of the thorax in newborns frequently leads to respiratory compromise and death in infancy. We report a family in which the diagnosis of JLS in a 1-year-old led to prenatal ultrasound diagnosis of JLS in a sibling. Aggressive neonatal care of the sibling, who developed respiratory failure soon after birth, led to an excellent outcome. This case confirms the utility of the prenatal ultrasound diagnosis of JLS and suggests that when the diagnosis of JLS is known prenatally, appropriate preparations can be made for specialized prenatal and postnatal care that may improve survival. PMID- 9373851 TI - Perinatal transport casebook. Maternal transport: a protocol for ambulance transfer from rural to regional facility. PMID- 9373853 TI - Comparison of tympanic and axillary temperature measurements. PMID- 9373852 TI - Special imaging casebook. Terminal myelocystocele. PMID- 9373854 TI - The potential role of IL-1 in the ovulatory process: an evolving hypothesis. AB - The intra-ovarian interleukin-1 (IL-1) system may be an intermediary in the ovulatory process. More specifically, it is hypothesized that intra-ovarian IL-1 may constitute a mediator of gonadotrophins in the induction of ovulation. The current evidence for and against this possibility is reviewed. PMID- 9373856 TI - Polymorphism of exon 3 of the HLA-G gene. AB - HLA-G is a non-classical MHC class I gene with a limited tissue distribution. The most pronounced expression is detected in the cytotrophoblast of first trimester placenta. It is possible to detect mRNA for HLA-G in preimplantation blastocysts where expression is correlated with a high cleavage rate of embryos. HLA-G seems to play an important role in the feto-maternal relationship. The polymorphism of the HLA-G locus is not fully clarified. One study has shown extensive nucleotide sequence variation in the exon 3 (alpha-2 domain) in healthy African Americans. A few studies in other populations have only revealed a limited polymorphism. We investigated the polymorphism of the exon 3 of HLA-G by means of Polymerase Chain Reaction (PCR)-Single Strand Conformation Polymorphism (SSCP)- and DNA sequencing analysis in a Danish population. We detected four single-base substitutions in exon 3 compared to the sequence of HLA-6.0 (G*01011); one of these has not been reported before. We also found a deletion of the first base of codon 130 or the third of codon 129 in a heterozygous individual. This study, together with previous results, suggests that the polymorphism of exon 3 of the HLA-G gene in Caucasians is limited, in contrast to that observed in Americans originating from Africa. Implications of this discrepancy and the detected deletion in relation to certain disorders of pregnancy are discussed. PMID- 9373855 TI - Steroid-level response to insulin-like growth factor-1 in oocytes matured in vitro. AB - The objective was to establish the influence of insulin-like growth factor-1 (IGF 1) on steroid production and nuclear maturation during oocyte in vitro maturation (IVM). Immature-selected rabbit follicular oocytes, divided as cumulus-oocyte complexes (COC) and denuded oocytes (DO), were cultured in Brackett's medium with different concentrations of IGF-1 at 0, 50, 100 and 200 ng/ml. After 8 and 16 h of culture, the oocytes were assessed for nuclear maturation by acetic-orcein stain, and media were analyzed by enzyme-immunoassay (EIA) for 17 beta-estradiol (E), progesterone (P), androstenedione (A) and testosterone (T) content. After culture treatments with IGF-1 significantly increased (P < 0.01) the incidence of nuclear activation (germinal vesicle breakdown stage, GVBD) and nuclear maturation (metaphase II stage); maximum stimulation occurred at 100 ng IGF-1/ml (86.9 vs. 49.3% in control). Compared to controls, the presence of IGF-1 in cultures was associated with a significant increase of E and A production by COCs (P < 0.01). However, P and T levels were not significantly influenced by the IGF 1. In addition, positive correlations between E/T and E/A ratios and nuclear maturation rates were only found in the IGF-1 treatments. Regarding the DOs, neither positive effects in nuclear maturation rates nor increase of steroid levels in culture were observed for any treatment. These results suggest that: (1) IGF-1 had a significant effect on E and A production during oocyte maturation; (2) the addition of IGF-1 enhanced nuclear maturation significantly in rabbit oocytes; and (3) all these effects are only possible in oocytes surrounded by cumulus cells. PMID- 9373857 TI - Evidence for a long-lasting single administration contraceptive vaccine in wild grey seals. AB - A single-administration birth control vaccine based on liposome delivery of porcine zona pellucida antigens reduced pup production in grey seals (Halichoerus grypus) by about 90%. Anti-porcine zona pellucida titers of individual seals with two or more recaptures were variable but without a diminishing trend during the 5 year post-immunization period. Seals that produced at least one or more pups during the 2-5 year post-immunization period when the vaccine is fully effective, had an average anti-porcine zona pellucida titer of 5% of the reference serum. In contrast, the subset of seals that did not reproduce but were recaptured during the breeding season had an average titer of 31% of the reference serum. As measured by antibody titers and pup production, there were no differences in efficacy of the vaccine in 14-, 20- and 21-year-old female grey seals. PMID- 9373859 TI - Can Th1-like immune responses explain the immunopathology of recurrent spontaneous miscarriage? PMID- 9373858 TI - Temporal trends in antibody production in captive grey, harp and hooded seals to a single administration immunocontraceptive vaccine. AB - The temporal production of antibody to a single-administration immunocontraceptive vaccine, known to be immunocontraceptive in free-ranging female grey seals (Halichoerus grypus), was studied in captive grey seals, harp seals (Phoca groenlandica) and hooded seals (Cystophora cristata). The vaccine is based on liposome delivery of porcine zona pellucida antigens. When measured by antigen capture, the response of hooded and harp seals to the vaccine was similar to the response of grey seals. Determination of antibody production by ELISA with protein A, ELISA with rabbit anti-seal immunoglobulin sera and SDS-PAGE after affinity chromatography confirmed the similarity in response to the vaccine by grey and harp seals, but suggested lower titers in hooded seals. The vaccine produced titers in captive, juvenile grey and harp seals known to be immunocontraceptive in wild, adult grey seals. PMID- 9373860 TI - Fumes from the spleen. PMID- 9373861 TI - Does gestational age in combination with birthweight provide better statistical adjustment of neonatal mortality rates than birthweight alone? AB - Between-area comparisons of neonatal mortality rates should be adjusted for differences in the underlying mortality risk. The traditional approach to this problem is to adjust neonatal mortality rates statistically for between-area differences in the birthweight distributions. However, in other types of perinatal research, birthweight is usually considered in combination with gestational age. For between-area comparisons of neonatal mortality rates, some researchers have argued that ad-justment by gestational age in addition to birthweight might not be necessary. This present study used graphical methods based on a non-parametric version of Poisson regression to underline the importance of examining neonatal mortality rates by both gestational age and birthweight. Six years of data from a whole-population database (Queensland Perinatal Data Collection) were used. The analysis also illustrates the value of non-parametric modelling in perinatal epidemiology. PMID- 9373862 TI - The association of pattern of maternal weight gain with length of gestation and risk of spontaneous preterm delivery. AB - Monitoring weight gain during pregnancy may be useful in detecting pregnancies that are at increased risk of early delivery. This study examines 7259 deliveries that occurred at the University of California, San Francisco's Moffitt Hospital from 1980 to 1990. Obese women, women with diabetes or hypertension during pregnancy, deliveries with congenital malformations and non-spontaneous preterm deliveries were excluded. Pattern of gain was assessed by fitting a quadratic curve to each woman's series of weight and date measurements, using simple regression techniques. The parameters from this curve were used to develop a variable for pattern of gain that reflects how much an individual's pattern of gain differs from a linear pattern of gain. Multivariable linear and logistic regression analyses indicate that patterns of gain that deviate greatly from the average pattern of gain (i.e. patterns that show a marked speeding up or slowing down of gain towards the end of pregnancy) are associated with significantly shorter gestational age and confer a significantly increased risk of spontaneous preterm delivery. The results suggest that monitoring weight gain during pregnancy is important, although more specific studies are needed to understand the mechanisms by which weight gain pattern relates to preterm delivery before appropriate interventions can be developed. PMID- 9373863 TI - The epidemiology of infantile hypertrophic pyloric stenosis. AB - Infants with infantile hypertrophic pyloric stenosis (IHPS) born from 1983 to 1988 and recorded in the California Birth Defects Monitoring Program (CBDMP) database were compared with their birth cohort by demographic characteristics and selected associated birth defects. We identified 1963 cases of IHPS for a cumulative incidence of 1.9 per 1000 livebirths. The cumulative incidence per 1000 livebirths was 2.4 in White, 1.8 in Hispanic, 0.7 in Black, and 0.6 in Asian infants. Between weeks 3-12 after birth, 1871 (95%) IHPS cases were diagnosed. Premature infants were diagnosed with IHPS later than term or post-term infants. The incidence of IHPS declined for those born to maternal age groups of > or = 25 years and, independently, for successive birth ranks. The probandwise concordance rate for IHPS in monozygous twins was less than unity (0.25-0.44), although higher than the concordance for dizygous twins (0.05-0.10). The incidence of Smith-Lemli-Opitz syndrome (SLO) diagnosed in infants with IHPS (3 of 1963) was 157-fold higher than the incidence of SLO diagnosed in the CBDMP population. IHPS occurs in all of the largest racial and ethnic groups in California, most frequently in White and Hispanic infants. Pyloric stenosis presents only within a brief phase of development, which may be delayed in premature infants. A predominant discordance of disease state in monozygous twins implies an aetiological role for undetermined environmental factors. The association between SLO, caused by deficient cholesterol synthesis, and IHPS deserves additional study. Infants with suspected SLO require close observation for the onset of IHPS. PMID- 9373864 TI - Twenty-year birth prevalence of Down syndrome in Cape Town, South Africa. AB - The 20-year birth prevalence of Down syndrome in Cape Town, South Africa, was determined. All cases delivered to mothers in Cape Town, plus terminations following prenatal diagnosis, between 1 January 1974 and 31 December 1993 were ascertained. There were 784 Down syndrome pregnancies, of which 95% were trisomies. The 32 terminations comprised 18.3% of the white, 5.8% of the coloured (mixed race) and 1.4% of the black cases. The overall prevalence rate was 1.49 per 1000 (white 1.88, coloured 1.54 and black 1.29 per 1000). Analysis for linear trends showed a significant decline in rates for the total population and for whites, a downward trend for coloureds, but no decline for blacks. Over the last 5-year period the prevalence rates in all three population groups were 1.3 per 1000. An increasing risk with advancing maternal age was confirmed, but no maternal age-specific differences in rates by race were demonstrated. PMID- 9373865 TI - Screening for galactosaemia in Greece. AB - Galactosaemia appears to be one of the most appropriate disorders for routine newborn screening as almost normal outcome can be achieved in most of the identified cases. Galactose and galactose-1-phosphate were determined using Guthrie cards in a commercial kit based on a colorimetric microassay. Among 199,642 newborns, nine cases with classic galactosaemia, three with epimerase deficiency, six with compound Duarte2/heterozygotes for galactosaemia and four with compound2 Duarte homozygosity were found. Even though the number found among the screened neonates is small because it is such a rare disease, our results indicate one of the highest frequencies of the disease ever reported. PMID- 9373866 TI - Breast feeding, pacifier use and infant development at 12 months of age: a birth cohort study in Brazil. AB - Many studies suggest that breast feeding confers developmental and intellectual advantages on children. In a recent study, however, no association was found between breast feeding and intelligence in adult life after adjustment for other variables, and the use of pacifier in infancy was the most important predictor of intelligence. We analysed the associations between breast-feeding duration, pacifier use and suspected developmental delay at 12 months of age in a birth cohort in Pelotas, southern Brazil. All 5304 hospital births occurring during 1993 were studied and a sample was followed up at 1, 3, 6 and 12 months of age. Breast-feeding practices and use of pacifiers were assessed at each visit, as well as suspected developmental delay, measured by the Denver II test. The prevalence of developmental delay was analysed, through logistic regression, according to breast-feeding status and pacifier use, accounting for the possible confounding effect of other variables. The prevalence of suspected developmental delay at 12 months was 34.1%, being slightly higher among children who used pacifiers at 6 months than among non-users (35.3% and 28.7% respectively). There was a marked negative association between breast-feeding duration and developmental delay, with children breast fed for 9 months or more presenting significantly less suspected developmental delay (25.5%) than those breast fed for less than 1 month (42.4%). The effects of multiple variables were tested, and only high parity, smoking during pregnancy, birthweight, gestational age, pacifier use and breast-feeding duration remained significantly associated with suspected developmental delay. The effect of pacifier use, however, disappeared after adjusting for breast-feeding duration, suggesting that breast feeding, and not pacifiers, affects child development. PMID- 9373867 TI - Trend in cerebral palsy birth prevalence in eastern Denmark: birth-year period 1979-86. AB - To investigate changes in cerebral palsy birth prevalence and perinatal mortality rate by different gestational age groups, 1979-86, cerebral palsy cases in eastern Denmark were identified from the Danish Cerebral Palsy Register, and information on birth and mortality rates was sought in the Danish Medical Birth Register. From 1979-82 to 1983-86, the birth prevalence of cerebral palsy increased from 2.6 to 3.0 per 1000 (P < 0.05). The rate for infants of 31 weeks' gestation or more did not change, whereas a significant increase was observed in infants below 31 weeks (85-123 per 1000, P < 0.05). In the same periods, perinatal mortality in eastern Denmark decreased significantly from 8.6 to 7.8 per 1000. The decrease in stillbirth rate was significant in all subgroups of gestational ages except in those of 28-30 weeks' gestation. The early neonatal mortality rate decreased significantly only in infants below 31 weeks (282-239 per 1000, P < 0.05). Thus, in eastern Denmark, cerebral palsy birth prevalence has increased from birth-year period 1979-82 to 1983-86 because of an increased rate in preterm infants below 31 weeks, who at the same time had a reduced risk of early neonatal death. PMID- 9373869 TI - Accumulation of phytate in vegetable-type soybean genotypes harvested at four developmental stages. AB - A total of 17 vegetable-type soybean (Glycine max [L.] Merr) genotypes were planted in four-row plots arranged in a randomized complete block design in 1988 and 1989 at Petersburg, Virginia. Each genotype was harvested at four developmental stages and evaluated for phytate content. Highly significant differences for phytate content were observed among the stages of harvest and genotypes, and there was an interaction between genotype x stage of harvest. The significant differences observed for phytate content among genotypes indicated that genetic variation exists among the tested genotypes for selection and improvement through hybridization. Among the genotypes, 'Kingston' and PI 423852 had the highest phytate content in most stages of harvest while PI 416771, 'Emperor', and PI 416982 had the lowest phytate values. A heritability estimate of 81 percent was observed for phytate content. This high heritability value indicates that selecting genotypes for lower phytate content would be effective. Significant correlations were observed for phytate content among genotypes harvested at R6, R7, R8, and overall. The magnitude of association of R6 with the overall phytate mean was especially high. These results illustrate that determining the phytate content of genotypes at the R6 growth stage would be a good predictor of the overall genotypic performance. PMID- 9373868 TI - The EURONIC Project: a European concerted action on information to parents and ethical decision-making in neonatal intensive care. AB - The paper presents the background, objectives and methods of a European concerted action project aimed at exploring the transmission of information to parents and the ethical decision-making process in neonatal intensive care from the perspective of health personnel, and in relation to the legal, cultural, social and ethical backgrounds of the various European countries. Eight countries are taking part in the project (France, Germany, Italy, Luxembourg, Spain, Sweden, The Netherlands and the United Kingdom), which is about to be extended also to Central and Eastern Europe (Estonia, Lithuania and Hungary). In each of them, the medical and nursing personnel of a number of randomly selected units will be interviewed through an anonymous, self-administered questionnaire. Information on the organisation and policies of the Units and on the national legislation will also be collected. The key features of the study lie in the multidisciplinary and international approach, the random selection of the sample as a guarantee of representativeness and lack of selection bias, the focus on the staff practices as well as on their attitudes and opinions. PMID- 9373870 TI - Effect of traditional processing practices on the content of total carotenoid, beta-carotene, alpha-carotene and vitamin A activity of selected Tanzanian vegetables. AB - The alpha-carotene, beta-carotene and total provitamin A carotenoids and the effect of traditional processing practices on the retention of these provitamins were studied using amaranth, cowpea, peanut, pumpkin and sweet potato leaves. Results of this study indicated that the content of total carotenoids, beta carotene and alpha-carotene were in the range of 26.79-44.74 mg, 4.16-19.12 mg, and 0.99-10.26 mg per 100 g of dry vegetables, respectively. The vitamin A activities were 4.042, 3.124, 0.829, 2.025 and 1.581 mg RE per 100 g of dry amaranth, cowpea, peanut, pumpkin and sweet potato leaves, respectively. The traditional processing practices of sun drying and storage in ventilated containers resulted in a significant (p < 0.05) decrease in the concentration of total carotenoids, beta-carotene and alpha-carotene for all the vegetables. Conventional blanching and cooking resulted in a significant (p < 0.05) increase in the concentration of carotenoids in the cowpea, peanut and pumpkin leaves while in amaranth and sweet potato greens, thermal processing resulted in a significant (p < 0.05) decrease in the concentration of these nutrients. PMID- 9373871 TI - Effect of pre-dehulling treatments on the composition of seeds of the legume Afzelia africana and its potential use in pastries. AB - Flour was prepared from seeds of Afzelia africana dehulled by different treatments and used to replace 10, 20, 30, 40 and 50% wheat flour in biscuits and doughnuts. The composition and water and oil absorption properties of the flour blends were evaluated. The biscuits and doughnuts made from each flour blend were evaluated organoleptically. The composite flour containing the highest proportion (50%) of A. africana seed flour contained the highest levels of protein and fat, exhibited the highest water absorption property but the lowest oil absorption capacity. Sensory scores showed high overall acceptability for products with a 10 30% level of substitution. PMID- 9373872 TI - Characteristics of two major lectins from mungbean (Vigna radiata) seeds. AB - Two major lectins, MBL-I and MBL-II, were purified from Vigna radiata L. seeds using ion-exchange and gel filtration chromatography techniques. MBL-I was found to be a tetramer with native M.W. of 132 kDa and subunit M.W. of 33 kDa having alpha-galactosidase activity. MBL-II consisted of two monomeric lectins with M.W. of 94 kDa and 89 kDa which were associated mainly with beta-galactosidase activity. Both MBL-I and MBL-II are D-galactose-specific lectins. PMID- 9373873 TI - Uptake of various trace elements during germination of wheat, buckwheat and quinoa. AB - The practice of sprouting is widely used to improve the nutritional value of grain seeds. Several nutritive factors such as vitamin concentrations and bioavailability of trace elements and minerals increase during germination. The objective of this work was to study the enrichment of various essential trace elements during germination of wheat (Triticum aestivum), buckwheat (Fagopyrum esculentum), and quinoa (Chenopodium quinoa) seeds in order to improve their nutritional role as a source of bioavailable trace elements. Seeds were sprouted either in distilled- or tap-water and in five different electrolyte solutions to investigate the concentration-dependent uptake. The time-dependence was investigated by analyzing aliquots of the sprouts after certain germination periods. Samples were analyzed after freeze drying for their Li, V, Cr, Fe, Mn, Co, Cu, Zn, Sr, Mo, As and Se concentrations with inductively-coupled plasma mass spectrometry (ICP-MS). As a control for possible changes in the biochemical metabolism of the sprouts, the biosynthesis of vitamin C was also determined by using reversed-phase ion-pair HPLC. It was shown that quinoa was the most resistant to the applied electrolyte solutions and had the highest uptake rates for almost all elements, followed by buckwheat and wheat. Greatest increases were observed for Co, Sr, and Li. No significant changes in vitamin C biosynthesis were observed between sprouts grown in different electrolyte solutions. The time dependent uptake for most elements was characterized by a significant absorption during soaking of the seeds, followed by a lag phase during the first day of germination and an increased uptake during the second and third day. Se and As showed distinctly different uptake behaviors. PMID- 9373874 TI - Effect of home processing and storage on ascorbic acid and beta-carotene content of Bathua (Chenopodium album) and fenugreek (Trigonella foenum graecum) leaves. AB - The present investigation was conducted to study the effect of selected processing and storage methods on the concentration of ascorbic acid and beta carotene in Bathua and fenugreek leaves. Methods included storage of leaves with or without polythene bags for 24 and 48 h in a refrigerator at 5 degrees C; at 30 degrees C in polythene bags; drying (sun and oven); blanching (5, 10, 15 min); open pan and pressure cooking. Ascorbic acid content of fresh leaves was 220.97 to 377.65 mg and beta-carotene content was 19.00 to 24.64 mg/100 g, DW. The percent loss of ascorbic acid ranged from 2.03 to 8.77 and 45.15 to 66.9 while lower losses (0.0 to 1.75 and 1.63 to 2.84) of beta-carotene were observed in leaves stored in the refrigerator and at 30 degrees C, respectively. A markedly greater reduction in ascorbic acid and beta-carotene was observed in dried, blanched and cooked leaves. The study data suggest that storage of leaves in refrigeration, drying in oven, blanching for a short time and cooking in a pressure cooker results in better retention of these two vitamins. PMID- 9373875 TI - Effect of processing on dietary fiber content of cereals and pulses. AB - Total dietary fiber (TDF), insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) content of rice, wheat, sorghum, maize, ragi, bajra, whole grains of pigeonpea, chickpea, green gram and lentil as well as their dehusked split dhals were analyzed. Cereals except rice flours were made into chapati (unleavened bread), while rice and dhals were cooked in a pressure cooker. After the processing, IDF and SDF contents of these foods were also analyzed. Among the cereals, rice had the lowest TDF (4.1%) and wheat had the highest (12.5%). TDF content of whole pulses ranged from 15.8% in lentil to 28.3% in chickpea. IDF as % of TDF constituted 85 to 89% in whole pulses. Dehusking of pulses into dhals decreased TDF and IDF contents significantly. Among the dhals, green gram dhal had the lowest (8.2%, 6.5%) and chickpea dhal (15.3%, 12.7%) had the highest TDF and IDF contents, respectively. Processing of cereals had no effect on their TDF and IDF contents, with the exception of ragi, where a significant increase in TDF and IDF was observed. Cooking of dhals brought about a significant increase in their TDF and IDF contents. PMID- 9373876 TI - Biomass yield and composition of sweetpotato grown in a nutrient film technique system. AB - Sweetpotato cultivar TU-82-155 grown in a nutrient film technique system and separated into foliage, tips, fibrous, string and storage roots at harvest had a total dry biomass of 89.9 g per plant with 38.4% inedible portion. Tips and storage roots, the traditional edible parts, were analyzed for dry matter, protein, fat, ash, minerals (Ca, Fe, K, Mg, Na, Zn), vitamins (carotene, ascorbic acid, thiamin), oxalic and tannic acids, and trypsin and chymotrypsin inhibitors to determine their nutritional quality. Water soluble matter, minerals (Ca, Fe, K, Mg, Na, Zn), cellulose, hemicellulose and lignin concentrations in the edible and inedible parts were obtained to provide information needed for the selection of appropriate bioconversion processes of plant wastes into food or forms suitable for crop production in a controlled biological life support system. PMID- 9373877 TI - Cyclooxygenases and the central nervous system. AB - Prostaglandins (PGs) were first described in the brain by Samuelsson over 30 years ago (Samuelsson, 1964). Since then a large number of studies have shown that PGs are formed in regions of the brain and spinal cord in response to a variety of stimuli. The recent identification of two forms of cyclooxygenase (COX; Kujubu et al., 1991; Xie et al., 1991; Smith and DeWitt, 1996), both of which are expressed in the brain, along with superior tools for mapping COX distribution, has spurred a resurgence of interest in the role of PGs in the central nervous system (CNS). In this review we will describe new data in this area, focusing on the distribution and potential role of the COX isoforms in brain function and disease. PMID- 9373878 TI - Production of prostaglandin F2 alpha and E2 in explants of intrauterine tissues of guinea pigs during late pregnancy and labor. AB - Prostaglandin production in amnion and decidua is considered important for human parturition. We investigated in pregnant guinea pigs, a species similar to women in regard to the endocrinology of pregnancy, whether the production rates of PGE2 and PGF2 alpha in various intrauterine tissues are compatible with a role in parturition. Net production rates were measured at 45, 55 and 65 days of gestation and during labor in amnion, chorion, myo-endometrium, the outer layer of the myometrium, the site of placental implantation, and placenta. Net production rates in amnion increased between 45 days and labor (30-fold for PGE2 and 8-fold for PGF2 alpha, P < 0.0001). During labor, the production rates in amnion of PGE2 (P = 0.006) and PGF2 alpha (P = 0.019) were higher than at 45, 55, and 65 days of gestation. In myo-endometrium, the production rates of PGF2 alpha were higher at 65 days of gestation than at 55 days and during labor (P = 0.046). Addition of arachidonic acid (10(-5) M) increased production of PGE2 and/or PGF2 alpha in all tissues (P < 0.05) except placenta. In amnion, the response to arachidonic acid increased with advancing gestation. This suggests that 1) PGE2 and PGF2 alpha produced by amnion have a potential role in the initiation and maintenance of labor, 2) PGF2 alpha produced by myo-endometrium has a potential role in the initiation of labor, 3) cyclooxygenase(s) are not rate-limiting except in placenta, and 4) the expression of cyclooxygenase in amnion increases with advancing gestation. PMID- 9373879 TI - The effect of dexamethasone on CRH and prostanoid production from human term placenta. AB - The human placenta at term produces large quantities of corticotropin releasing hormone (CRH) and prostanoids. These hormones play an important role in the maintenance of pregnancy, and the initiation and progress of labor; yet little is known of factors affecting their regulation and the interrelationship of CRH and prostanoid production. In these studies we have investigated the effect of dexamethasone on the production of CRH and prostanoids from fresh human term placental tissues. The basal release of prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2 alpha), thromboxane B2 (TxB2) and 6-keto-prostaglandin F1 alpha (6 keto-PGF1 alpha) from human term placental explants increased from the fifth hour in culture, while the release of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) was not significantly changed during this period. The addition of dexamethasone (10(-8) M) to the perifusing medium resulted in a rapid and dramatic inhibition of PGE2, PGF2 alpha, PGFM, TxB2 and 6-keto-PGF1 alpha release. On the other hand, CRH release was not significantly changed throughout the seven hours of incubation with dexamethasone. These data demonstrate that glucocorticoids at physiologic concentrations can inhibit human term placental prostanoid production, and thus glucocorticoid production may play an important role in the physiological regulation of placental prostanoid production in the human placenta. However, dexamethasone did not alter CRH release, demonstrating that the inhibition of placental prostanoids by dexamethasone is not a CRH mediated event. PMID- 9373880 TI - Measurements of urinary prostaglandins in young ovulatory women during the menstrual cycle and in postmenopausal women. AB - The purpose of the present work was to study the prostaglandin excretion in young nonpregnant ovulatory women during the menstrual cycle on the one hand and in postmenopausal women on the other hand and to investigate the influence of female sex hormones (estradiol, progesterone) on urinary prostanoid excretion. Urinary excretion rates of prostaglandin E2 (PGE2), 6-keto-PGF1 alpha, thromboxane B2 (TxB2) and their metabolites PGE-M (11 alpha-hydroxy-9, 15-dioxo-2,3,4,5,20 pentanor-19-carboxyprostanoic acid), 2,3-dinor-6-keto-PGF1 alpha, 2,3-dinor-TxB2 and 11-dehydro-TxB2 were determined by gas chromatography-triple stage quadrupole mass spectrometry (GC/MS/MS) in 41 young non-pregnant women during the follicular phase and during the luteal phase and in 23 postmenopausal women. Excretion rates of all urinary prostanoids were not significantly different in the follicular phase when compared with the luteal phase. In contrast to the young ovulatory women, PGE2 and TxB2 were significantly higher in postmenopausal women. Concerning the other prostaglandins significant differences between these groups of women did not exist. Although serum levels of estradiol and progesterone were different in young and postmenopausal women, sex hormones have not been shown to correlate with prostaglandins. Our data do not suggest sex hormones to be responsible for the difference in the prostaglandin excretion in women of reproductive age and in women in the menopause. Further systematic investigations into age dependency of prostaglandin excretion in women are necessary. PMID- 9373881 TI - Naltrexone enhances ovulation and prostaglandin synthesis in the rat ovary. AB - We explored the action of beta-endorphin (beta E) and naltrexone (Nal) on the number of oocytes and on prostaglandins (PGE and PGF2 alpha) production by the ovaries from PMSG/hCG-primed immature and cycling rats. Superovulated rats were injected with beta-endorphin (0.5 microgram) intraperitoneally 4 hours after hCG. The number of ova ovulated was inhibited and this effect was blocked with naltrexone injected into the ovarian bursa (0.1 microgram) 30 minutes before beta endorphin. Furthermore, beta-endorphin (10(-8) M) decreased prostaglandins production by ovaries isolated 4 hours after hCG. Intraperitoneal injection of beta-endorphin (0.5 microgram) at 17:00 hr on proestrus decreased (-23%) the number of ova within oviducts on the day after (estrus). Naltrexone injected intraperitoneally (5 micrograms) at 16:30 hr on proestrus increased the number of ova (+23%). On the other hand, beta-endorphin increased the number of oocytes obtained by puncture of antral follicles (+37%) and naltrexone decreased the number of oocytes (-33%). Prostaglandins content in the ovary of adult rats at 23:00 hr, approximately 4 hr before the onset of ovulation, was diminished when the rats received beta-endorphin at proestrus. Moreover, when the rats were injected with naltrexone, ovarian production of prostaglandins was increased. Our results further support the hypothesis that beta-endorphin affects ovulation at the level of the ovary in the rat and that endogenous opioids may be modulating this physiological process. PMID- 9373882 TI - Decreased 5-HT1A and increased 5-HT2A receptor binding after chronic corticosterone associated with a behavioural indication of depression but not anxiety. AB - The effects of chronic corticosterone treatment (100 mg pellet implanted for 1 week) were assessed in animal tests of anxiety, exploration and motor activity, and changes in binding to 5-HT1A and 5-HT2A receptors, and the 5-HT transporter, were measured. At the end of the week's treatment, the corticosterone concentration was significantly elevated and there were significant decreases in adrenal, thymus and body weights. However, there were no changes in the measures of anxiety in the social interaction test or on trials 1 and 2 of the elevated plus-maze. Also supporting a dissociation between anxiety and elevated corticosterone concentrations are previous findings that benzodiazepine withdrawal causes increased anxiety but no change in corticosteroid concentrations. Therefore these two situations provide a double dissociation between anxiety and elevated corticosteroids. Decreased 5-HT1A receptor binding in the dentate gyrus and increased 5-HT2A receptor binding in the parietal cortex was found following chronic corticosterone treatment. This reciprocal relationship between 5-HT1A and 5-HT2A receptors has been proposed to be important in mediating depression. The significant decreases in motor activity observed in all the test situations would be compatible with this proposal. Thus the constellation of behavioural and biochemical changes detected after chronic corticosterone treatment is more pertinent to depression than anxiety. One week after removal of the pellets, the behavioural and neurochemical changes had disappeared and the only differences to remain were decreased adrenal, thymus and body weights in the animals that had been treated chronically with corticosterone. PMID- 9373883 TI - Insulin-like growth factor-I (IGF-I) plasma concentrations are increased in depressed patients. AB - There is some evidence that the somatotrophic system in depression, as assessed by basal growth hormone (GH) concentrations and by GH releasing hormone (GHRH) challenge, might be dysfunctional. However, the rather limited data have been inconclusive so far and plasma concentrations of both insulin-like growth factor 1 (IGF-I) and binding proteins (IGFBP 1 to IGFBP-6) have not been measured simultaneously in depressed patients. We studied 24 severely depressed patients and 33 healthy controls and estimated 24-hour mean plasma cortisol, six-hour evening mean plasma growth hormone (GH), morning plasma IGF-I, IGFBP 2 and 3 and GH-binding protein (GH-BP). Twenty-four-hour mean cortisol (306 +/- 69 vs. 196 +/ 30 nmol/l, p < .001) and IGF-I (157 +/- 40 vs. 120 +/- 33 micrograms/l, p < .01) plasma concentrations were found to be significantly increased in depressed patients, while there was no difference in GH or binding proteins between both groups. MANOVA analysis revealed age and diagnosis to have main effects upon plasma IGF-I. Especially young age and a diagnosis of major depression are associated with higher plasma IGF-I. After treatment only patients in remission had attenuated IGF-I plasma concentrations. We conclude that plasma IGF-I is increased in acutely depressed patients similar to other states of hypercortisolemia. PMID- 9373884 TI - Early androgen effects on aggression in children and adults with congenital adrenal hyperplasia. AB - Males are more likely than females to show aggressive behavior across species, ages, and situations, and these differences may be partly influenced by early hormones. We studied aggression in three samples of subjects with congenital adrenal hyperplasia (CAH), who were exposed to high levels of androgen in the prenatal and early postnatal periods. Controls were siblings and first cousins similar in age. In Sample 1, adolescents and adults completed the Multidimensional Personality Questionnaire (MPQ), which includes an Aggression scale. In Sample 2, adolescents and adults completed the MPQ and a paper-and pencil version of Reinisch's Aggression Inventory. In Sample 3, parents rated the aggression of children aged 3-12, using a modification of Reinisch's Inventory. In all three samples, control males had higher aggression scores than control females. Further, as predicted, females with CAH had higher aggression than control females, but the difference was significant only in adolescents and adults. These results suggest that early androgens contribute to variability in human aggression. PMID- 9373885 TI - Cerebrospinal fluid and plasma beta-endorphin in combat veterans with post traumatic stress disorder. AB - Opioid-mediated analgesia develops in experimental animals following traumatic stress and increased opioid-mediated analgesia has been observed in combat veterans with post-traumatic stress disorder (PTSD). These observations have led to the hypothesis that increased central nervous system (CNS) opioidergic activity exists in patients with PTSD. However, direct CNS data on opioid peptide concentrations and dynamics in patients with PTSD are lacking. We withdrew cerebrospinal fluid (CSF) via a flexible, indwelling subarachnoid catheter over a 6-h period and determined hourly CSF concentrations of immunoreactive beta endorphin (ir beta END) in 10 well-characterized combat veterans with PTSD and nine matched normal volunteers. Blood was simultaneously withdrawn to obtain plasma for ir beta END. PTSD symptom clusters, as measured by the CAPS, were correlated with neuroendocrine data. Mean CSF ir beta END was significantly greater in patients with PTSD compared with normals and there was a negative correlation between the ir beta END and PTSD intrusive and avoidant symptoms of PTSD. No intergroup difference between plasma ir beta END was found, nor was there a significant correlation between CSF and plasma ir beta END. Immunoreactive beta-lipotropin (ir beta LPH) and pro-opiomelanocortin (irPOMC), both precursors of beta END, were much more plentiful in human CSF than was beta endorphin itself, as has been previously reported. It remains to be determined whether the increased CNS opioid concentrations predate traumatic stress, thereby conferring a vulnerability to dissociative states and PTSD itself, or result from the trauma. The negative correlation between CSF ir beta END and avoidant and intrusive symptoms suggests that CNS hypersecretion of opioids might constitute an adaptive response to traumatic experience. Poor correlation between CSF and plasma ir beta END limits use of plasma measures to assess CNS opioid activity. PMID- 9373886 TI - Different control mechanisms of growth hormone (GH) secretion between gamma-amino and gamma-hydroxy-butyric acid: neuroendocrine evidence in Parkinson's disease. AB - The observation that baclofen stimulates growth hormone (GH) secretion in normal men, but not in parkinsonian patients led us to test the GH releasing effect of other gamma-amino-butyric acid (GABA)ergic agents with different mechanisms of action in Parkinson's disease. For this purpose 10 normal men and 10 de novo parkinsonian patients were tested with sodium valproate (800 mg PO), gamma hydroxybutyric acid (GHB) (25 mg/kg body weight PO) and baclofen (10 mg PO). All drugs induced a significant increment in serum GH levels in the normal controls. On the other hand, GH secretion in parkinsonian patients did not change after baclofen or sodium valproate administration, whereas it showed normal responsiveness to GHB. These data suggest that the mechanism underlying the GH response to GHB is different from that (or those) mediating sodium valproate and/or baclofen action. In addition, the former, but not the latter mechanism appears to be preserved in the parkinsonian brain. PMID- 9373887 TI - Serotonergic function and negative and depressive symptomatology in schizophrenia and major depression. AB - BACKGROUND: Serotonergic abnormalities are found in both major depressive disorder (MDD) and schizophrenia. Depressive symptoms commonly occur alongside the negative or defect symptoms in schizophrenia and antiserotonergic drugs may be particularly effective in their treatment. We wished to explore whether these symptoms could be distinguished biologically by directly comparing serotonergic function in these two illnesses. METHOD: Fifteen patients with MDD and 13 patients with schizophrenia underwent testing with the specific serotonin releasing agent D-fenfluramine (D-FEN). Prolactin and cortisol responses were measured to ascertain central serotonergic function. Individual patient results were compared with their own carefully matched control to correct for the effect of age, sex, weight and menstrual cycle, before the two patient groups were then compared. RESULTS: Prolactin responses differed significantly between the two patient groups, being lower in MDD patients and higher in schizophrenia patients than their individually matched controls. Cortisol responses did not differ. Within the schizophrenia group, increased serotonergic function correlated positively with depressive symptoms, but there was no such correlation with defect symptoms. Depressive scores were negatively correlated with the presence of negative symptoms in the schizophrenic group. CONCLUSIONS: Schizophrenia and MDD have distinct and opposite neuroendocrine responses to D-FEN. There is no evidence that depressive symptoms in these two conditions have a common serotonergic basis. Moreover, these responses distinguished between negative and depressive symptoms in our schizophrenic group. PMID- 9373888 TI - Relationships of serum estradiol levels, menopausal duration, and mood during hormonal replacement therapy. AB - A study was undertaken in 38 menopausal women on-cyclic HRT (estropipate) and estropipate + nor-ethindrone). Serum estradiol levels during treatment were related to mood changes and platelet MAO activity. The relationship between serum estradiol levels and mood changes was found to be a function of the duration of menopause. Women with a short duration of menopause (12.9 months +/- 6.1) were compared to women with a long duration of menopause (76.6 months +/- 52.3). Women with a short duration of menopause had significantly lower mean serum estradiol levels during HRT compared to women with a long duration of menopause (216.9 +/- 62.3 vs. 291.13 +/- 118.12, respectively, p < .02). It had previously been reported that estrogen treatment in menopausal women had a positive effect on mood, whereas the combination of estrogen plus a progestin had a negative effect on mood. We found that the women with a long duration of menopause and higher treatment serum estradiol levels had significantly more dysphoria when receiving a combination of estrogen plus progestin than did the women with a short duration of menopause and lower serum estradiol levels. However, both short and long duration menopausal groups showed improvement in mood when estrogen was administered alone. Platelet MAO levels, a marker of adrenergic and serotonergic function thought to relate to mood, were negatively correlated with serum estradiol levels during HRT. We suggest that these paradoxical findings may be secondary to a prolonged estrogen deficiency state in women with a long duration of menopause. PMID- 9373889 TI - Deficits in multiple systems of working memory in schizophrenia. AB - Working memory, the ability to hold and manipulate information 'on-line' in a temporary memory store, is impaired in schizophrenia. This impairment may be characterized within the framework of two opposing theoretical models: (1) central executive as coordinator of component processes of working memory or (2) multiple independent systems of spatial and object memory. In order to test which of these models better explains the working memory deficit of schizophrenia, 14 schizophrenic patients and 12 age- and gender-matched control subjects performed tests of spatial memory (dot location), object memory (shapes, color dots) and a dual paradigm (dot location + shapes). If schizophrenia impairs the central executive, a group-by-task interaction would demonstrate excessively worse performance on the dual than single tasks in schizophrenics relative to controls; however, the absence of an interaction would be consistent with deficits in the multiple working memory systems. The schizophrenic group was significantly impaired on all measures, and both the schizophrenic and control performance was worse on the dual than the single tasks. Despite the schizophrenic group performance deficits on the single tasks, the extent of such deficit did not appear additive and contributive to the dual tasks. The lack of a group-by-task interaction provided no support for the central executive model of dysfunction. Rather, the results uphold the model of working memory deficits arising from compromise of multiple (here spatial and object), relatively independent systems, both of which are affected in schizophrenia. PMID- 9373890 TI - Is Wisconsin Card Sorting Test performance related to 'working memory' capacity? AB - The Wisconsin Card Sorting Test (WCST) is a multifactorial and complex test, and it involves so many different kinds of functions that it is difficult to understand why patients fail. Capacity of 'working memory' is possibly involved in the WCST performance and is considered a relevant factor responsible for the schizophrenics' poor performance. The present study was specifically designed to assess the relationship between 'working memory' measurements and WCST performances of schizophrenics. Furthermore, we investigated the relationship between the cognitive dysfunction and the clinical symptomatology. The following tests were administered to 30 schizophrenics and 25 healthy subjects: WCST, Digit Span Test (Backward and Forward), Digit Symbol Substitution Test and Visuo Spatial 'working memory' Test, a card test appropriately devised. Clinical assessment included the Italian version of the scale of Krawiecka Manchester Scale (K-MS) and the Outcome scale by Strauss and Carpenter (1972). The 30 patients differed significantly in all the neuropsychological variables from the controls. WCST indexes did not correlate significantly with any of the 'working memory' measures (visuo-spatial and verbal) in the samples studied. No relationship was seen between the neuropsychological performances and clinical symptomatology as evaluated by the K-MS scale. WCST indexes and DSST significantly correlated with the outcome measure. The results do not support the hypothesis that executive dysfunction as evaluated by WCST is attributed to 'working memory' impairment, rather they could suggest that these two neuropsychological functions identify different neurocognitive constructs. PMID- 9373892 TI - Executive functioning deficits in hypothetically psychosis-prone college students. AB - Executive functioning deficits have been identified in schizophrenics, their family members, in persons with schizophrenic spectrum disorders, and in others psychometrically at high risk for future psychosis. In the present study, a group hypothesized to be at high risk for future psychosis (Chapman and Chapman, 1985; Chapman et al., 1994) showed no generalized cognitive deficit, but demonstrated impairments on two executive functioning measures (Wisconsin Card Sorting Test and Stroop Color and Word Test) as compared to control students. Results suggest that executive function deficits, particularly impaired inhibitory control, appear in individuals who may be at risk of later decompensation into a psychotic state, and thus may be important in the pathogenesis of schizophrenia and schizophrenic spectrum disorders. PMID- 9373891 TI - Regional cerebral blood flow during the Wisconsin Card Sort Test in schizotypal personality disorder. AB - Regional cerebral blood flow (rCBF) was measured by single photon emission computed tomography in 10 patients with schizotypal personality disorder (SPD) and nine age- and sex-matched normal volunteers. Subjects performed both the Wisconsin Card Sort Test (WCST) and a control task, the Symbol Matching Test (SMT). Four-way analyses of variance were performed to assess relative rCBF of the prefrontal cortex and of the medial temporal region. Normal volunteers showed more marked activation in the precentral gyrus, while SPD patients showed greater activation in the middle frontal gyrus. Relative flow in the left prefrontal cortex was correlated with better WCST performance in normal volunteers. SPD patients, however, showed no such correlations in the left prefrontal cortex, but demonstrated correlations of good and bad performance with CBF in the right middle and inferior frontal gyrus, respectively. Thus, at least some SPD patients demonstrate abnormal patterns of prefrontal activation, perhaps as a compensation for dysfunction in other regions. PMID- 9373893 TI - Insight, neurocognitive function and symptom clusters in chronic schizophrenia. AB - Only recently has there been interest in the systematic study of insight in schizophrenia. The present investigation was designed to evaluate the specific relationship between psychopathological symptoms, neurocognitive deficits and awareness of illness in chronic schizophrenia. Fifty-eight outpatients with the DSM-III-R diagnosis of schizophrenia were rated on David's Schedule for Assessing Insight, the Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale and the Wisconsin Card Sorting Test (WCST). Results indicate that there is a significant association among these variables and that approximately 44% of the variance in the dependent variable could be explained by this combination of independent variables. Notably, however, negative symptoms were only moderately inversely correlated with awareness of illness, and they were not associated with scores on the WCST. Moreover, neither negative symptoms nor per cent perseverative errors contributed significantly to the prediction of insight in schizophrenia. These findings argue against the notion that unawareness of illness is the product of neuropsychological dysfunction in the frontal lobes. Instead, the most significant associations and predictors of insight were related to the positive symptoms of schizophrenia. PMID- 9373894 TI - Ventricular volume and asymmetry in schizotypal personality disorder and schizophrenia assessed with magnetic resonance imaging. AB - Magnetic resonance imaging (MRI) was performed in 12 patients with schizotypal personality disorder (SPD), 11 patients with chronic schizophrenia, and 23 age- and sex-matched normal volunteers. MRI slices were acquired in the axial plane at 1.2-mm intervals, and the ventricles were traced on every other slice. The lateral ventricular system was divided into the anterior horn, temporal horn, and dorsal lateral ventricle. Schizophrenic patients had larger left anterior and temporal horns than the normal volunteers. Size of the left anterior and temporal horn in SPD patients was intermediate between those of normal volunteers and schizophrenic patients and differed significantly from schizophrenic patients. The left-minus-right difference was larger in schizophrenic patients than in normal volunteers or SPD patients. Thus, in their structural brain characteristics, as well as in their clinical symptomatology, SPD patients evidence, in attenuated form, abnormalities resembling those found in full fledged schizophrenia. The findings suggest that decreased left hemispheric volume, in frontal and temporal regions, may characterize both psychotic and non psychotic disorders of the schizophrenia spectrum. PMID- 9373895 TI - Focal signal hyperintensities in schizophrenia. AB - The presence of focal signal hyperintensities on MRI images of the brain was compared in 48 schizophrenic patients, 26 patients with bipolar disorder and 34 healthy controls. Significantly larger areas of brain were affected by focal signal hyperintensities, particularly in the frontal lobes, in the schizophrenic group compared to the bipolar group and the controls. Although the bipolar group had more such foci than controls, this difference did not reach statistical significance. PMID- 9373896 TI - Proton magnetic resonance spectroscopy of the anterior cingulate region in schizophrenia. AB - The authors measured N-acetylaspartate (NAA, a putative neuronal marker), choline and creatine in the anterior cingulate region of 26 schizophrenic patients and 16 control subjects using in vivo proton magnetic resonance spectroscopic imaging (1H MRSI). Relative to the control group, the patients with schizophrenia demonstrated significantly lower NAA in both the right and left anterior cingulate regions. There was no association between NAA and duration of illness or medication dosage. No group differences or lateralized asymmetries in choline or creatine were noted. The NAA findings provide support for either neuronal dysfunction or neuronal loss in the anterior cingulate region in schizophrenia. The absence of choline signal elevation does not support accelerated turnover of membrane phospholipids which might be expected if there were ongoing neuronal atrophy or neuronal necrosis. PMID- 9373897 TI - Gender-specific decline and seasonality of births in operationally defined schizophrenics in Italy. AB - All clinical records of schizophrenic patients included in the period 1979-1995 in the South Verona Psychiatric Case Register were reviewed and diagnoses operationally defined according to ICD-10 criteria using OPCRIT 3.1. Among the 335 scrutinized, 205 patients met the ICD-10 criteria for paranoid or undifferentiated schizophrenia. No seasonality of birth was found in these patients using a log-linear equiprobability model. The incidence and seasonality of birth were then analysed on the subsample of 106 patients born in 1947-1974 for whom corresponding data for the Verona general population were available. Schizophrenic males displayed a significant excess of birth in November-January with respect to the Verona population (chi 2 = 10.93, p = 0.012). The time series of the incidence of schizophrenia by cohort of birth 1947-1974 had a linearly decreasing trend, steeper in males than in females. The significant increase in age at first ever psychiatric contact, observed in both males and females throughout the period considered, cannot completely account for the gender specific decline of birth of schizophrenics. PMID- 9373898 TI - Catatonia and other motor syndromes in a chronically hospitalized psychiatric population. AB - BACKGROUND: To determine the motor characteristics of chronic catatonia, catatonia and other motor disorders were systematically rated in a long-term hospitalized sample. METHOD: Chronically hospitalized psychiatric inpatients (N = 42) with a clinical diagnosis of catatonic schizophrenia (295.2X) were rated for catatonia with a novel 23-item catatonia rating scale, and for parkinsonism, dyskinesia and akathisia using standard rating scales with scale-based criteria for case definition. RESULTS: Catatonia was the sole motor syndrome in nine cases (21%), co-existed with parkinsonism in five (12%), tardive dyskinesia in four (10%), and both parkinsonism and tardive dyskinesia in 10 (24%). There was no correlation between total scores across the four rating scales. 'Rigidity' was the sole catatonic sign which overlapped with other scales. The symptom profile of catatonia in this chronic sample was similar to previous reports based on acutely ill patients. CONCLUSION: Catatonia is distinguishable from other motor disorders in chronic psychiatric patients using the 23-item catatonia rating scale. The features of chronic catatonia are described, and the distribution of catatonic signs is similar for chronic and acute catatonia. PMID- 9373899 TI - Menstrually related symptom changes in women with schizophrenia. AB - In this study, affective, somatic, behavioral and psychotic symptom ratings were collected daily in an attempt to evaluate the level and significance of menstrual cycle changes in a cohort of women with a DSM-III-R diagnosis of schizophrenia. Thirty-nine hospitalized women were examined longitudinally on the Brief Psychiatric Rating Scale and the retrospective and prospective versions of the Premenstrual Assessment Form. Results indicated that similar to normal and depressed women, the symptoms that were most exacerbated were affective and somatic in nature, rather than psychotic symptoms that are characteristic of schizophrenic symptomatology. In addition, the presence and exacerbation of the symptoms were not specific to the premenstrual phase. Some symptoms were reported menstrually and postmenstrually. Overall the findings did not confirm exacerbation of symptoms that are specific to schizophrenia. Rather, menstrually related changes seem to be a discrete phenomenon with its own symptom profile which may be superimposed on psychiatric disorders, both those with and without a predominant affective component. However, it should be noted that all subjects were on psychotropic medication that could have obscured fluctuations of psychotic symptoms. Further investigation and clearer guidelines are necessary for determining the ovulatory cycle and endocrine factors in this population before any conclusions can be made. PMID- 9373900 TI - Solid-state 19F NMR investigation of poly(vinylidene fluoride) with high-power proton decoupling. AB - The use of high-power proton decoupling has enabled highly-resolved spectra of fluorine polymers to be recorded, as is exemplified herein for semicrystalline poly(vinylidene fluoride) (PVDF). By means of high MAS speeds (up to 17 kHz), the spinning sidebands are removed from the whole of the relevant chemical shift range. For spectra of the crystalline regions of the polymer, the high-power decoupling is necessary, though its effect is not large. Various relaxation techniques have been used to examine the semicrystallinity and the polymorphism of PVDF, with special pulse sequences used to discriminate between the various domains. Different chemical shifts have been observed for the signals of the amorphous and crystalline phases. Those of the more immobile parts cover a substantial range. PMID- 9373901 TI - T1 rho in nuclear quadrupole resonance: a theoretical study. AB - A new NQR method of measuring the spectral density of slow motions in solids is proposed. It is shown that also in NQR a 90 degrees phase shift of a resonant rf magnetic field following a 90 degrees pulse locks the nuclear magnetization in a 'rotating frame' similarly as in NMR. The spin-lattice relaxation time T1 rho of the locked magnetization is calculated in general for an arbitrary spin. It is assumed that the fluctuations of the EFG tensor dominate the spin-lattice relaxation. The calculations show that T1 rho depends on the spectral density J(omega) of the electric quadrupole fluctuations at the NQR frequencies, and also at a low frequency omega. Here omega approximately gamma B1 kHz depends on the orientation of the rf magnetic field in the principal-axis system of the EFG tensor. The term containing J(omega) in the expression for T1 rho-1 depends on the orientation of the rf magnetic field in the principal-axis system of the EFG tensor, only through the orientation dependence of omega. This term vanishes when the electric quadrupole fluctuations do not modulate the frequency of the NQR transition excited by the rf magnetic field. Two particular examples: I = 1 and I = 3/2 are worked out in details. PMID- 9373902 TI - NMR study of solid C60(gamma-cyclodextrin)2. AB - A solid complex of C60 with gamma-cyclodextrin (gamma-CyD) was examined with NMR spectroscopic methods in order to understand the dynamics of C60, and the interaction between C60 and gamma-CyD. A 13C solid-state cross-polarization magic angle spinning (CP/MAS) NMR spectra shows C60 resonance at 142.6 ppm. This provides the evidence of interaction between 13C spins in C60 and 1H spins in the gamma-CyD host. Ambient temperature experiments on the 13C CP/MAS NMR, with varying contact time, shows that the water associated with gamma-CyDs plays an important role in the nuclear relaxation processes. The dynamics of C60 in gamma CyD was investigated using temperature and field-dependent 13C spin-lattice relaxation time measurements. The influence of water on the dynamics of C60 was less significant below 250 K. PMID- 9373903 TI - Solid state NMR study of sodium thiocyanate/poly(ethylene oxide) electrolytes. AB - 1H-, 13C-, 23Na-solid state NMR measurements have been used to characterise the morphology and the dynamics of several NaSCN-PEO mixtures. Selective 13C-MAS experiments allowed to determine the composition of the (PEO)nNaSCN samples in terms of the different phases present, as well as the real stoichiometry of the crystalline complex. 1H- and 13C-spin-lattice relaxation times provided estimates of the dimensions of the different domains and gave information on the dynamics of the polymer chains. 23Na-MAS spectra and 2D nutation experiments allowed to individuate the presence of different environments for the sodium cations on the basis of their quadrupolar interactions. PMID- 9373904 TI - Effects of paramagnetic cations on the nonexponential spin-lattice relaxation of rare spin nuclei in solids. AB - Nonexponential spin-lattice relaxation is often observed for rare spin nuclei in the solid state. Deviation from single-component decay may be amplified by the coupling of rare spin nuclei to paramagnetic centers. Nonexponential spin-lattice relaxation was observed in derivatized silica gels resins. This phenomenon was localized and enhanced when paramagnetic transition metal cations were bound to surface functional groups. A stretched exponential analysis method was determined to be robust in fitting nonexponential relaxation curves for silica gels both with and without bound paramagnetic ions. Spin-lattice relaxation rates (T1(-1)) for functional group nuclei increased as a function of percent surface coverage with metal ion. The magnitude of the relaxation rate increase was dependent upon internuclear distances from the paramagnetic center. At low surface coverages, a semi-random distribution of paramagnetic centers increased the degree of stretching of spin-lattice relaxation decays, as measured by decreases in the calculated stretching parameter beta. At higher surface coverages, calculated beta values reached a limiting value, indicating that while the spin-diffusion mechanism in metal-exchanged silica gels is restricted, it is not completely diminished. PMID- 9373906 TI - Stray-field imaging of quadrupolar nuclei of half integer spin in solids. AB - A report is presented on the observation of Hahn echoes from the following quadrupolar nuclei of half integer spin (I) in polycrystalline solids in the large static magnetic field gradient (37.5 T/m) which exists in the fringe field of a superconducting solenoid: 7Li, 23Na, 11B, 65Cu (I = 3/2); 27Al (I = 5/2); 51V, 59Co (I = 7/2); and 115In (I = 9/2). 23Na echo-trains from NaCl (with non selective excitation) and from Na2SO4 (with selective excitation) are compared quantitatively for two different RF pulse sequences: 90x-(tau-90y-tau-echo-)n and 90x-(tau-90x-tau-echo-)n. The signals obtained from RF pulses corresponding to non-selective 90 degrees pulses were shown to be quantitative, whereas in the selective case smaller signals were obtained since only the central transition contributed. The loss of signal from this cause can be distinguished from small signals resulting from low density of nuclei by use of the second sequence. A 7Li image obtained from LiF in a cylindrical glass-vial is shown. PMID- 9373905 TI - Characterization of Spanish sepiolites by high-resolution solid-state NMR. AB - 29Si NMR (MAS and CP/MAS) and 1H MAS NMR techniques were used to characterize four sepiolites, two of natural origin (commercialized under the names Pangel and Pansil) and the other two obtained from them by treatment with 2 M or 4 M H2SO4, respectively. These techniques were used to identify the structural and surface changes undergone by sepiolites by the effects of acid treatment and calcination. Various types of Si were detected; also, treatment with 4 M H2SO4 destroyed the sepiolite and produced fibrous silica. PMID- 9373909 TI - Histological determinants of the vascular surface in prostatic carcinoma. AB - This study was performed to analyse the correlation between vascular surface (VS), tumour grade and stage and relative proportion of tumour cells within the tumour stroma. Specimens of 41 prostatic carcinoma were immunostained using Factor VIII-related antigen. The VS was assessed by means of stereology. In tumour-free prostatic tissue the VS was 6.7 +/- 0.4 mm-1. In pT2 tumours this value was significantly increased to about 12 mm-1. With rising pT stage the VS significantly decreased to values of 4 in pT4 tumours. In G1 tumours the VS was 14.6 mm-1 and significantly decreased with decreasing grade of differentiation. No significant difference was obtained between pN0 and pN+ cases. A close positive correlation (r = 0.59, P < 0.001) existed between the VS and the relative proportion of tumour cells within the tumour, whereas a strong negative correlation was found between the VS and the relative amount of tumour stroma (r = 0.81, P < 0.001). The VS mainly depends on tumour differentiation and pT stage, i.e. the tumour size and the relative proportion of stroma and tumour cells within the tumour. These results are consistent with those obtained in experimental tumours. Assessment of the VS is therefore of interest in studies of tumour biology; it is of no use in predicting lymph node metastasis. PMID- 9373907 TI - 31P to 77Se cross polarization in beta-P4Se3. AB - Cross polarization from 31P to 77Se is demonstrated in beta-P4Se3. This material, an inorganic glass, is readily synthesized from the elements and serves as a convenient sample for setting the Hartmann-Hahn condition. PMID- 9373908 TI - Early detection and early treatment. PMID- 9373910 TI - Decrement of blood flow precedes the involution of the ventral prostate in the rat after castration. AB - Blood flow to the rat ventral prostate (VP), dorsolateral prostate (DP), and Dunning R3327 prostatic tumors was measured at different times up to 7 days after castration, using the microsphere method. In the VP organ weight was decreased from day 3 onwards. Blood flow was, however, already significantly decreased from day 1. The reduced blood flow in VP in 1-3 and 7-day castrated animals could be reversed by testosterone treatment. Organ weight was slightly decreased but blood flow was unaffected by castration in DP. Castration left Dunning tumor volume and blood flow unaffected. Using immunohistochemistry, androgen receptors were observed in epithelial and stromal cells in VP, DP and Dunning tumors, but not in blood vessels. Castration is known to induce apoptosis in the VP, but not in the DP or in Dunning tumors. This suggests that a reduction in blood flow might be an important component for the castration-induced involution and apoptosis in prostatic tissue. The reason why castration reduces blood flow only in the VP, and not in the DP or Dunning tumor is unknown. PMID- 9373911 TI - A histopathological mapping study of the urinary bladder tumors induced by N butyl-N-(4-hydroxybutyl)nitrosamine in dogs. AB - Bladder tumors were induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in five Beagles and four mongrel dogs. The tumors were observed for long periods and the tumor progression was traced using histopathological mapping. The results indicated (1) that low-dose BBN over a long period induced multiple low-grade (G1 2) and low-stage (pTa-1) papillary tumors, resembling superficial bladder cancer in humans; (2) that high-dose BBN over a short period induced high-grade (G2-3) and high-stage (pT3b) nonpapillary tumors and carcinoma in situ (CIS) resembling invasive cancer and CIS in humans; (3) that beagle dogs required longer periods and higher total doses of BBN as compared with mongrel dogs; (4) that the tumors induced by low-dose BBN in beagles were observed without BBN as long as the animals lived, and neither increasing numbers of tumors nor malignant features such as deep infiltration and metastasis was observed; and (5) that low-dose BBN seems to induce mild dysplasia, which is followed by Brunn's nest-like proliferation in the lamina propria and nodular change, eventually leading to the development of papillary noninvasive transitional cell carcinoma (TCC); and that high-dose BBN seems to induce severe dysplasia which leads to CIS and nonpapillary invasive TCC. These results may contribute to clarifying the natural history of human bladder cancer. PMID- 9373912 TI - Flow cytometric evaluation of transferrin receptor in transitional cell carcinoma. AB - We evaluated flow cytometric (FCM) analysis of transferrin receptor (TFR) expression as a marker for the malignant potential in transitional cell carcinoma (TCC). TCCs from 55 patients were analyzed by FCM using an anti-TFR monoclonal antibody (CD71) and a TCC-specific monoclonal antibody (EH14), which recognizes most TCC cells irrespective of the grade. The cells were divided into subpopulations according to DNA ploidy determined simultaneously. TFR expression correlated well with the grade and the stage of the tumors. TFR expression of the aneuploid tumors was significantly higher than that of the euploid tumors in all subpopulations. EH14 expression did not correlate with the grade or the stage of the tumors. EH14 expression of the aneuploid tumors was significantly higher than that of the euploid tumors in the whole cell population but not in the subpopulations. In moderately differentiated tumors or in T1 tumors, TFR expression was higher in multiple or recurrent tumors than in simple tumors. The cell size or shape were not the primary reasons for the enhanced expression of TFR in the high-grade or the high-stage tumors; instead, overproduction of TFR may take place in these tumors. Clinically, many of the TCC tumors are grouped into G2 or T1 tumors, some of which will be invasive cancers. Quantitative analysis of TFR expression using FCM may be useful to predict the prognosis of these tumors. PMID- 9373913 TI - Electrolyte equilibration of human kidneys during perfusion with HTK-solution according to Bretschneider. AB - Twelve surgically removed human kidneys (mainly tumor kidneys) were investigated. The investigations comprised perfusion criteria (perfusion flow, perfusion pressure, perfusion resistance, electrolyte equilibration). During perfusion of the kidneys with HTK solution, the perfusion resistance was nearly three times as high in human kidneys as in canine kidneys perfused under the same conditions in previous studies. Beside possible species differences the raised perfusion resistance may be explained by the greater trauma to the human kidneys due to the surgery, the primary ischemic stress which cannot be avoided clinically and the often nonoptimal initial diuresis. Nevertheless definitive perfusion is possible under clinical conditions although pronounced increases of perfusion resistance may occur. As indicated by the raised perfusion resistance of human kidneys under clinical conditions as compared with canine kidneys in an experimental model, electrolyte equilibration of human kidneys was protracted. For this reason, a duration of perfusion of at least 10 min is necessary in clinical application of HTK solution, i.e., longer than in animal experiments. PMID- 9373914 TI - Sweat urea, uric acid and creatinine concentrations in uraemic patients. AB - Concentrations of creatinine, uric acid and urea were measured in the blood and urine of female patients at the final stage of renal disease and on a regular lifelong programme of haemodialysis. The samples were collected in winter-time and in summertime. The same analytes were also measured in sweat fluid at the time of collecting summer samples. The results showed insignificant physiological seasonal changes for creatinine and uric acid and that the concentration of these compounds in the sweat fluid was low. Urea concentration in the sweat fluid was found to be present at a much higher concentration than the serum level (reaching in some cases 50 times the serum level). The possibility of using thermal induction as an alternative to haemodialysis is suggested. The presence of urea in the sweat fluid at such a high level suggests a selective transport mechanism across the eccrine sweat gland to clear the blood of a high urea level. PMID- 9373915 TI - Involvement of superoxide radical in the impaired endothelium-dependent relaxation of cavernous smooth muscle in hypercholesterolemic rabbits. AB - Involvement of the superoxide radical in impaired relaxation of penile cavernous smooth muscle in hypercholesterolemia was investigated. New Zealand White rabbits (n = 40) were randomly divided into control and treatment groups. The control group (n = 20) received a regular diet while the treatment group (n = 20) was fed a diet of 2% cholesterol for 8 weeks. Blood level of cholesterol in the cholesterol-fed group was significantly higher than that of the control group. The contraction responses of cavernous tissues to norepinephrine were not significantly different in the two groups. The relaxation responses to endothelium-dependent agents (acetylcholine, bradykinin) were significantly reduced in the hypercholesterolemic group compared with the control group. However, the relaxation responses to endothelium-independent agents (papaverine, verapamil) were not significantly different in the two groups. The production of superoxide radicals was significantly higher in the hypercholesterolemic group than in the control group (P < 0.01). The activity of superoxide dismutase (total SOD, Mn-SOD, Cu,Zn-SOD) increased significantly in the hypercholesterolemic group compared with the control group (P < 0.05). The activities of catalase and glutathione peroxidase also increased in the hypercholesterolemic group, but were not significantly higher than those of the control group. Therefore, production of the superoxide radicals in rabbit cavernous tissues increases in the state of hypercholesterolemia, which may lead to functional impairment of cavernous smooth muscle relaxation in response to endothelium-mediated stimuli. PMID- 9373916 TI - Biochemical and quantitative analysis of Tamm Horsfall protein in rats. AB - The involvement of Tamm Horsfall protein (THP) in nephrolithiasis is currently under investigation in several laboratories. Although rat is a commonly used species as an in vivo model for such studies, there is only limited information available about the biochemical properties and excretion profile of THP in normal rats. In order to characterize rat THP, we purified and analyzed normal male rat THP, and compared it with normal human male urinary THP by gel electrophoresis. Both THPs migrated at approximately 90 KDa, and stained similarly for protein (Coomassie blue) as well as carbohydrates (periodic acid Schiff reagent). Compositional analysis revealed that rat THP was largely similar to human THP in amino acid and carbohydrate contents but showed differences in the individual sugar components from other mammals. There was considerable variation in the day to-day urinary excretion of THP in normal rats, with values ranging from 552.96 micrograms to 2865.60 micrograms and a mean value of 1679.54 micrograms per 24 h. It was concluded from this study that rat THP did not contain any unusual biochemical components and was primarily similar to human THP in composition and mean urinary concentration. PMID- 9373917 TI - Characterization of protein components of human urinary crystal surface binding substance. AB - We previously extracted crystal surface binding substance (CSBS) from human urine and showed that it appeared to constitute a substantial proportion of urinary macromolecular inhibitors of calcium oxalate crystallization. CSBS was isolated from human urine and fractionated by three consecutive chromatography procedures in order to characterize protein inhibitors of calcium oxalate crystallization. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and NH2 terminal amino acid sequencing revealed that inhibitory fractions eluted from a final, hydroxyapatite column contained prothrombin and osteopontin. Hydroxyapatite column fractions also contained other, unidentified protein inhibitors of calcium oxalate crystallization. CSBS contained also human serum albumin, alpha 1-acid glycoprotein, alpha 1-microglobulin, alpha 2-HS glycoprotein, retinol-binding protein, transferrin, and Tamm-Horsfall protein, but these proteins seemed to play no direct role in inhibitory activity. PMID- 9373918 TI - Expression of heparan sulfate proteoglycan mRNA in rat kidneys during calcium oxalate nephrolithiasis. AB - This study used reverse transcription polymerase chain reaction (RT-PCR) to examine heparan sulfate proteoglycan (HS-PG) mRNA expression levels during stone formation in the rat kidney. Total RNA in kidneys was extracted and converted to cDNA. PCR products were resolved by electrophoresis on 1.5% agarose gel and visualized with ethidium bromide. Fragment intensity and area were measured using an image analyzer. Control cyclophilin and HS-PG mRNAs were expressed in all samples examined as 235 bp and 506 bp bands, respectively. Cyclophilin expression in the normal group was not significantly different from expression in the group that formed stones. However, the level of HS-PG mRNA expression apparently increased in calcium oxalate (CaOx) microlith. The findings suggest an association between CaOx nephrolithiasis and expression of HS-PG in the rat kidney. PMID- 9373919 TI - Evaluation of urine composition and calcium salt crystallization properties in standardized volume-adjusted 12-h night urine from normal subjects and calcium oxalate stone formers. AB - The volume of 12-h night urine from ten normal men (NM), ten normal women (NW) and 31 male calcium stone formers (SFM) was adjusted to 750 ml and analysed with respect to supersaturation with calcium oxalate (CaOx) and calcium phosphate (CaP), inhibition of CaOx crystal growth and aggregation, as well as the CaOx and CaP crystallization propensity. Concentrations of oxalate and glycosaminoglycans and AP(CaOx) index, an estimate of the CaOx ion-activity product, were higher and the concentration of citrate lower in NM than in NW. In SFM the directly assessed risk of CaOx crystallization was higher and the inhibition of CaOx crystal growth lower than in NM. There were no differences between the groups regarding inhibition of CaOx crystal growth by 74% dialysed urine or inhibition of CaOx crystal aggregation. SFM with mixed CaOxCaP stones had a higher concentration of phosphate and a higher AP(CaP) index at pH 7.0 than SFM with CaOx stones. PMID- 9373920 TI - Supercritical fluids: an interesting medium for chemical and biochemical processes. AB - Interactions between solute and solvent in supercritical fluids (SCFs) are of fundamental importance because small changes in pressure or temperature near the critical point may alter reactivity in chemical and biochemical processes, and were examined such as those for ester synthesis catalyzed by a lipase in supercritical carbon dioxide and for a FT-IR study on the structures of reverse microemulsions in supercritical ethane. We previously conducted ester synthesis from acyl donors and terpene alcohols catalyzed by Candida cylindracea (CCL) lipase in supercritical carbon dioxide. In the near-critical region, (S)-(-) terpene esters were stereoselectively synthesized from acyl donors and a primary alcohol such as (+/-)-citronellol. In a very limited pressure range near the critical point, interactions between carbon dioxide and enzyme molecules greatly increased with consequent drastic conformational changes in the enzyme, causing active sites to emerge to catalyze stereoselective synthesis. Therefore, supercritical carbon dioxide medium in the near-critical region should trigger the activation of the enzyme by causing movement of its surface groups and creating active sites. Two molecular aggregates, an enzyme and micelle, in supercritical fluids were studied with respect to their microstructure and activity for chemical reactions. High-pressure FT-IR spectroscopy has thus been used to clarify (i) the rotational isomerism of AOT molecules, (ii) characteristics of water and the water-head group, and (iii) RSO3-Na+ interactions in AOT reverse micellar aggregates in supercritical ethane. At 35.0 MPa, the proportion of trans-like to gauche-like conformers greatly increased as W0 was increased. A system of water/AOT/supercritical ethane was in a one-phase microemulsion state at W0 values less than 15 at 35.0 MPa and 306.1 K. At higher W'0 the system was in a two-phase state. The addition of lithium chloride makes the system become motionless in a one-phase microemulsion state at W0 above 30. This work demonstrates interesting pressure-, temperature, and salt effects on an enzyme-catalyzed esterification and/or maintenance of a one-phase microemulsion in supercritical fluids from practical and theoretical points of view. PMID- 9373921 TI - ELPAT Program report: background and current status (July 1997). PMID- 9373922 TI - Hearing thresholds, threshold repeatability, and attenuation values for passive noise-reducing earphone enclosures. AB - Passive noise-reducing earphone enclosures contain a supra-aural earphone mounted in a plastic dome. These enclosures are used to prevent the elevation of hearing thresholds due to masking from high levels of ambient noise. This research determined normal hearing threshold levels, threshold repeatability, and attenuation values for an Audiocup, Auraldome II, AudioMate, and Madsen ME-70 enclosure. In Study I hearing thresholds were obtained for 30 normally hearing adults from 500 to 6000 Hz in four test sessions for each enclosure and a supra aural earphone attached to a headband. The hearing thresholds and repeatability for the Audiocup and Auraldome were similar but the thresholds were higher and repeatability was poorer for the AudioMate and Madsen ME-70 compared with the supra-aural earphone. In Study II real-ear attenuation values were obtained for each enclosure using 24 normally hearing subjects. The Audiocup and Auraldome II provided less low-frequency attenuation compared with the AudioMate and Madsen ME 70. The findings were related to the coupling of the supra-aural earphone in each enclosure to the ear and the coupling of each enclosure to the head. If an enclosure is used as an alternative to a supra-aural earphone for hearing testing in high ambient noise environments, hearing thresholds and threshold repeatability should be similar to a supra-aural earphone, and the enclosures should provide adequate attenuation of ambient noise. Since none of the enclosures met all of these requirements their use is not recommended for hearing testing. PMID- 9373923 TI - Interlaboratory and intralaboratory variabilities in the Environmental Lead Proficiency Analytical Testing (ELPAT) Program. AB - The Environmental Lead Proficiency Analytical Testing (ELPAT) Program evaluates over 400 laboratories that perform lead measurements in paints, soils, and dusts. A previous National Institute for Occupational Safety and Health study, based on the ELPAT data over a 3-year period (1992-1995), found no large biases among common hotplate and microwave digestion techniques, but did detect small consistent bias between two common instrumental methods. This study expands on the earlier study by examining the total sample variability and its variation components (interlaboratory and intralaboratory). A correlation model was used to separate the variation components by estimating a variation ratio. The correlation model leads to a more general approach than a sample pairing technique developed by Youden. This study found no significant evidence that the relative contribution of intralaboratory and interlaboratory variability to total variability changes with lead loading levels. There were no significant differences in the relative contribution of variation components among three most commonly used analytical methods (combinations of sample preparation techniques and instrumental methods). The interlaboratory relative standard deviation is about 1.7 times the intralaboratory relative standard deviation. Both variation components are important parts of total variation although the laboratory-to laboratory (including analyst-to-analyst) difference is greater than the within laboratory (including sample-to-sample) variation. PMID- 9373924 TI - Carbon monoxide poisonings from small, gasoline-powered, internal combustion engines: just what is a "well-ventilated area"? AB - This study modeled the time required for a gasoline-powered, 5 horsepower (hp), 4 cycle engine to generate carbon monoxide (CO) concentrations exceeding the National Institute for Occupational Safety and Health 200-ppm ceiling and 1200 ppm immediately dangerous to life and health concentration for various room sizes and ventilation rates. The model permitted the ambiguous term "well-ventilated area" to be defined. The model was compared with field data collected at a site where two workers were poisoned while operating a 5-hp concrete saw in a bathroom having open doors and an operating ventilation system. There is agreement between both the modeled and field-generated data, indicating that hazardous CO concentrations can develop within minutes. Comparison of field and modeling data showed the measured CO generation rate at approximately one-half of the value used in the model, which may be partially because the engine used in the field was not under load during data collection. The generation rate and room size from the actual poisoning was then used in the model. The model determined that ventilation rates of nearly 5000 ft3/min (120 air changes per hour) would be required to prevent the CO concentration from exceeding the 200-ppm ceiling for short periods. Results suggest that small gasoline-powered engines should not be operated inside of buildings or in semienclosed spaces and that manufacturers of such tools should improve their warnings and develop engineering control options for better user protection. PMID- 9373925 TI - Field evaluation of endotoxin air sampling assay methods. AB - This study tested the importance of filter media, extraction and assay protocol, and bioaerosol source on the determination of endotoxin under field conditions in swine and poultry confinement buildings. Multiple simultaneous air samples were collected using glass fiber (GF) and polycarbonate (PC) filters, and these were assayed using two methods in two separate laboratories: an endpoint chromogenic Limulus amebocyte lysate (LAL) assay (QCL) performed in water and a kinetic chromogenic LAL assay (KQCL) performed in buffer with resistant-parallel line estimation analysis (KLARE). In addition, two aqueous filter extraction methods were compared in the QCL assay: 120 min extraction at 22 degrees C with vigorous shaking and 30 min extraction at 68 degrees C with gentle rocking. These extraction methods yielded endotoxin activities that were not significantly different and were very highly correlated. Reproducibility of endotoxin determinations from duplicate air sampling filters was very high (Cronbach alpha all > 0.94). When analyzed by the QCL method GF filters yielded significantly higher endotoxin activity than PC filters. QCL and KLARE methods gave similar estimates for endotoxin activity from PC filters; however, GF filters analyzed by the QCL method yielded significantly higher endotoxin activity estimates, suggesting enhancement of the QCL assay or inhibition of the KLARE asay with GF filters. Correlation between QCL-GF and QCL-PC was high (r = 0.98) while that between KLARE-GF and KLARE-PC was moderate (r = 0.68). Analysis of variance demonstrated that assay methodology, filter-type, barn-type, and interactions between assay and filter-type and between assay and barn-type were important factors influencing endotoxin exposure assessment. PMID- 9373926 TI - Infectious waste management and laboratory design criteria. AB - Infectious waste management and laboratory design criteria are provided to help in recognizing what information needs to be included in an individual program and to develop an infectious waste management plan. Relevant engineering aspects of a containment laboratory are described in detail, and suggested equipment and operating procedures for collection, sterilization, and disposal of solid and liquid waste are discussed. The need for public awareness regarding infectious waste is discussed, including liability considerations associated with improper disposal. This study shows how proper management of infectious waste results in lower disposal cost, lower operating costs, reduction in liabilities, increased worker safety, and a cleaner environment. PMID- 9373927 TI - Utilization of glycosyltransferases to change oligosaccharide structures. AB - Carbohydrates on cell surfaces are important biomolecules in various biological recognition processes. Elucidation of the biological roles of complex oligosaccharides necessitates an efficient methodology to synthesize these compounds and their analogs. Enzymatic synthesis renders itself to be useful in the construction of an oligosaccharide structure owing to its mild reaction condition, high regio- and stereoselectivity. This review article focuses on the recent progress in oligosaccharide syntheses catalyzed by glycosyltransferases, namely sialyltransferase, galactosyltransferase, fucosyltransferase, and N acetylglucosaminyltransferase. A survey of the latest patent and literature related to this field is also included. PMID- 9373929 TI - Synthesis of N-acetylneuraminyl-alpha 2,3(6)lactose-malate dehydrogenase conjugate for detecting sialic acid terminal groups on glycoproteins via homogeneous lectin-based enzyme-linked binding assay. AB - An N-acetylneuraminyl-alpha 2,3(6)lactose-malate dehydrogenase (MDH-Lac-Neu5Ac) conjugate is prepared via an isothiocyanate conjugation method using a p aminophenethylamino derivative of sialyllactose. The newly synthesized conjugate can be utilized as a reagent in a novel homogeneous lectin-based, enzyme-linked, competitive binding assay (1-3) for probing the specific carbohydrate structure and content of intact glycoproteins. The enzymatic activity of the MDH-Lac-Neu5Ac conjugate is shown to be significantly inhibited (35%) by sialic acid-binding lectin, Limax flavus agglutinin (LFA), and this inhibition is reversed by mucin, a glycoprotein possessing sialic acid terminals. The asialo form of mucin, however, binds weakly to LFA, yielding no substantial increase in the MDH-Lac Neu5Ac activity at comparable glycoprotein concentrations. Use of the newly synthesized conjugate in conjunction with LFA or other lectins capable of binding sialic acid may provide a rapid and convenient way to detect the presence and relative amount of sialic acid terminal groups within intact glycoprotein structures. PMID- 9373930 TI - Diffusion and transfer of antibody proteins from a sugar-based hydrogel. AB - Diffusion of antibody protein from hydrogel films and hydrogel encapsulated in a microcapillary was studied. Thin hydrogel films were formed by crosslinking 6 acryloyl-B-O-methylgalactoside with N,N'-methylene-bis-acrylamide and the diffusive transport of monoclonal antimouse IgG-FITC into and out of the hydrate films was measured. Diffusion coefficients in 2 and 4% crosslinked hydrogel films were measured. The measured diffusion constants determined for IgG in both the 2 and 4% hydrogel films were comparable to the free diffusion of IgG in bulk water (Dmean approximately 10(-7) cm2/s). In addition, 2% crosslinked hydrogels were prepared in a capillary tube and the transport of antimouse IgG-FITC into and out of the hydrated hydrogel was measured. Kinetic analysis indicated that the protein transport through the capillary hydrogel was faster than would be expected for a simple diffusion process. Finally, by utilizing the diffusion of antibody from the capillary hydrogel, transfer of antibody to a silica surface was demonstrated. A capillary hydrogel loaded with antimouse IgG-FITC was used to transfer the protein to a silica surface forming a 30-micron spot of antibody, which was imaged using fluorescence microscopy. These results may lead to the development of a nonlithographic method of patterning antibodies on surfaces for use in integrated microimmunosensors. PMID- 9373931 TI - Production of succinate from glucose, cellobiose, and various cellulosic materials by the ruminal anaerobic bacteria Fibrobacter succinogenes and Ruminococcus flavefaciens. AB - The production of organic acids by two anaerobic ruminal bacteria Fibrobacter succinogenes S85 and Ruminococcus flavefaciens FD-1, was compared with glucose, cellobiose, microcrystalline cellulose, Walseth cellulose (acid swollen cellulose), pulped paper, and steam-exploded yellow poplar as substrates. The major end product produced by F. succinogenes from each of these substrates was succinate (69.5-83%), the principal secondary product was acetate (16-30.5%). Maximum succinate productivity ranged from 14.1 mg/L.h for steam-exploded yellow Poplar to 59.7 mg/L.h for pulped paper. For R. flavefaciens, the major end product from cellobiose, microcrystalline cellulose, and acid-swollen Walseth cellulose was acetate (39-46%), pulped paper and steam-exploded yellow poplar yielded succinate (42-54%) as the major product. Maximum succinate productivity by R. flavefaciens ranged from 9.21 mg/L.h for cellobiose to 43.1 mg/L.h for pulped paper. In general, much less succinate was produced at a lower maximum productivity by R. flavefaciens than by F. succinogenes under similar fermentation conditions. The maximum succinate productivities by these two organisms are comparable to the previously reported value of 59 mg/L.h for Anderobiospirillum succiniciproducens grown on glucose and corn steep liquor. PMID- 9373932 TI - Improved manufacture and application of an agarose magnetizable solid-phase support. AB - A simple, semiautomated, nonhazardous procedure for the production of a magnetizable solid-phase support (MSPS) has been developed based on the extrusion of molten agarose-iron oxide mixtures, which enables manufacture of a range of differently sized spherical agarose-iron oxide beads. This system has enabled scale-up of an original manufacture procedure and reproducible preparation of kg quantities of MSPS suitable for biomolecular purifications. An improved protocol for the isolation of plasmid DNA directly from cell lysates using this MSPS, derivatized with diethylaminoethyl (DEAE) groups, is reported. This involves a modified alkaline lysis, followed by adsorption to and elution from the support, yielding plasmid DNA of a purity comparable with, or better than, other methods of plasmid isolation. Using the same procedure, plasmid DNA can be isolated from bacterial cell culture volumes of 1.5 mL and 100 mL with equal efficiency and purity. PMID- 9373933 TI - Studies on the synthesis of two tetrasaccharides and the reactivity difference between them. AB - Studies on the reactivity of two synthetic tetrasaccharides as glycosyl acceptors showed that condensation of the methyl alpha-glycoside with a disaccharide donor afforded a hexasaccharide, but condensation of the methyl beta-glycoside with the disaccharide did not yield the corresponding hexasaccharide under the same conditions. A combination of theoretical results and 2D NMR indicated that the reactivity difference between the methyl alpha-glycoside and the methyl beta glycoside was determined mainly by steric effects. PMID- 9373934 TI - Synthesis and evaluation of eight aminodeoxy trisaccharide inhibitors for N acetylglucosaminyltransferase-V. AB - N-Acetylglucosaminyltransferase-V is an important enzyme controlling the branching pattern of N-linked oligosaccharides. This enzyme recognizes the trisaccharide octyl 2-acetamido-2-deoxy-beta-D-glucopyranosyl-(1-->2)-alpha-D mannopyranosyl -(1-->6)-beta-D-glucopyranoside (5) as a substrate and adds a beta linked GlcNAc residue to OH-6 of the central alpha-Man unit. Eight analogs of 5 were chemically synthesized where C-6 of the alpha-Man residue in 5 was deoxygenated, and structurally diverse modifications were introduced at C-4 of the same residue. The key intermediate prepared for this purpose was octyl 2 acetamido-2-deoxy-beta-D- glucopyranosyl-(1-->2)-4-amino-4,6-dideoxy-alpha-D mannopyranosyl- (1-->6)-beta-D-glucopyranoside (7a) where the original 4'-amino group was readily derivatized on the unprotected sugar. The eight analogs 7a-7h were evaluated as inhibitors for GlcNAcT-V, both isolated (from hamster kidney) and cloned (from rat kidney). All of the compounds were found to be competitive inhibitors with Ki in the range of 3-106 microM. The conclusion of this work is that recognition of acceptor 5 does not involve contact of the C-6--C-4 end of the alpha-Man residue with the protein in the E-I (or E-S) complex. PMID- 9373935 TI - Isolation and characterization by electrospray-ionization mass spectrometry and high-performance anion-exchange chromatography of oligosaccharides derived from hyaluronic acid by hyaluronate lyase digestion: observation of some heretofore unobserved oligosaccharides that contain an odd number of units. AB - Hyaluronic acid was degraded with hyaluronate lyase (E.C. 4.2.2.1, from Streptomyces hyalurolyticus), and the resulting oligosaccharides up to dp 16 were characterized by electrospray-ionization mass spectrometry (ESIMS) and high performance anion-exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). In accordance with the known regiospecificity of the enzyme, the products included even-numbered oligosaccharides of structure beta-D-4en-thrHexpA (1-->3)-[beta-D-GlcpNAc-(1-->4)-beta-D- GlcpA]n-(1-->3)-D-GlcpNAc. Minor amounts of novel and unexpected odd-numbered oligomers, having the structure beta-D-4en thrHexpA-(1-->3)-[beta-D-GlcpNAc-(1-->4)-D-Glc pA]n, were also isolated and characterized. This study, in addition to others beginning to appear in the literature, demonstrates the usefulness of ESIMS and HPAEC-PAD in the analysis and characterization of anionic glycosaminoglycan-type oligosaccharides. PMID- 9373936 TI - The relationship between the structures of the O polysaccharides from Escherichia coli O17 and O16. AB - The chemical structure of the O16 antigen from the lipopolysaccharide of Escherichia coli strain P4 has been determined. Comparison with the structures of other O16 antigens and that of the O17 antigen explains the previously reported cross-reaction of O antigen from the O16 strain K-12 with anti-O17 antibody [D. Liu and P.R. Reeves, Microbiology, 140 (1994) 49-57]. PMID- 9373937 TI - Structural studies on the Shigella-like Escherichia coli O121 O-specific polysaccharide. AB - The O-specific polysaccharide isolated from the lipopolysaccharide (LPS) of Escherichia coli O121 by mild acid hydrolysis has been studied using mainly NMR spectroscopy. The polysaccharide was treated with mild base to yield a O deacetylated polysaccharide which contained D-GlcNAc, D-GalNAcA, D-GalNAcAN (2 acetamido-2-deoxy-D-galacturonamide) and D-Qui4NAcGly (where D-Qui4N is 4-amino 4,6-dideoxy-D-glucose) in equimolar proportions. The presence of the amide was confirmed by recording the 1H NMR spectrum of the O-deacetylated polysaccharide at different pH values. The O-acetyl group was located on O-3 of the GalNAcAN and the structure of the polysaccharide can be written as [sequence: see text] This structure is almost identical to that previously reported for the O-specific polysaccharide of Shigella dysenteriae type 7 LPS, the only difference being that O-acetylation is stoichiometric in the latter. PMID- 9373941 TI - Solid-phase synthesis of a glycosylated peptide fragment of the IL-8 receptor containing two vicinal oligosaccharide chains. PMID- 9373940 TI - Deacetylation of chitin oligosaccharides of dp 2-4 by chitin deacetylase from Colletotrichum lindemuthianum. AB - Chitin oligosaccharides of degree of polymerization 2-4 were deacetylated by purified chitin deacetylase isolated from Colletotrichum lindemuthianum to give their corresponding breakdown products after purification by liquid chromatography. Data from FABMS analyses suggested that N,N',N",N"' tetraacetylchitotetraose and N,N',N"-triacetylchitotriose were converted into fully-deacetylated corresponding chitosan oligomers. Conversely, N,N' diacetylchitobiose [(GlcNAc)2] was deacetylated to give a product which showed an [M + H]+ pseudomolecular ion at m/z 383, suggesting that either of the two acetyl groups were removed. Further data from 1H NMR analyses confirmed that the reaction product was 2-acetamido-4-O-(2-amino-2-deoxy-beta-D-glucopyranosyl)-2 deoxy-D-glucos e [GlcN-GlcNAc]. The enzymatic method has three advantageous characteristics over chemical methods: (i) it does not cause unexpected degradation of the sugar chain, (ii) it is highly reproducible, and (iii) unique compounds such as GlcN-GlcNAc may be produced. PMID- 9373938 TI - Structure of a phosphorylated polysaccharide from Shewanella putrefaciens strain S29. AB - A phosphorylated polysaccharide was isolated from the aqueous layer of the phenol water extract of a non-halophilic bacterium Shewanella putrefaciens strain S29. The glycosyl phosphate linkage in the polysaccharide was split under mild acid conditions to give, after borohydride reduction, a phosphorylated oligosaccharide alditol. On the basis of sugar analysis and 1H, 13C and 31P NMR spectroscopy, including 2D COSY, relayed COSY, rotating-frame NOE spectroscopy (ROESY), heteronuclear 13C,1H COSY, and H-detected heteronuclear 1H,31P multiple-quantum coherence (HMQC), it was concluded that the polysaccharide is built up of tetrasaccharide-phosphate repeating units having the following structure: [sequence: see text] where QuiNAc and Qui4NAc are 2-acetamido-2,6-dideoxyglucose and 4-acetamido-4,6-dideoxyglucose, respectively. PMID- 9373942 TI - Developmental fate of single embryonic stem cells microinjected into 8-cell-stage mouse embryos. AB - Embryonic stem (ES) cells are pluripotent and capable of differentiating into somatic as well as germ cell lineages when conjoined with blastomeres of early mouse embryos. However, the developmental potential of single ES cells has not been fully investigated. We injected single murine ES cells (A3-1 cell line) of 129 origin into 8-cell mouse embryos (B6xBDF1) and examined the patterns of distribution of ES-cell-derived cells in the blastocysts as well as in the fully grown chimeric mice. The ES cells underwent 1-2 cycles of mitosis between the 8 cell and the blastocyst stage when they were introduced as single cells, whereas those introduced as groups of 2-5 cells did not proliferate during the same period of development. The ES cells and their daughter cells were predominantly incorporated into the ICM. From the 63 8-cell embryos which received single ES cells microinjected into the perivitelline space, 24 newborns were obtained, and 4 (2 fertile males, 1 sterile female and 1 hermaphrodite) of them (16.6%) were chimeric. The test breeding studies revealed that all the progeny of the two chimeric males were derived from spermatozoa of 129 genotype. The relative contribution of the host-derived and the ES-cell-derived cells in different tissues of the chimeric mice was assessed by PCR analyses of the microsatellite polymorphism of genomic DNA extracted from the tissues. In two male germ line chimeras, the testes, the kidneys and the dorsal skeletal muscles exhibited exceptionally high 129 contents. Our results demonstrated that single ES cells which maintain totipotency or pluripotency of high degree are present in a colony of ES cells, and that single ES cells conjoined with the blastomeres of 8-cell stage embryos may colonize, if the circumstances allow, almost exclusively the germ cells and concomitantly the urogenital cell lineages. Possible correlation between the allocation of the germ line and the urogenital lineages is discussed. PMID- 9373943 TI - Differential expression of the murine histone genes H3.3A and H3.3B. AB - The histone family of proteins is subdivided into two major groups: the main type histones, which are synthesized in coordination with DNA replication during the S phase of the cell cycle, and the replacement histones, which can be synthesized in the absence of DNA replication substituting main type histone isoforms. Accumulation of replacement histone variants has been observed in several terminally differentiated tissues that have stopped cell division. The replacement subtype of the H3 class is termed H3.3. This protein is encoded by two different genes (H3.3A and H3.3B) that both code for the same amino acid sequence, but differ in nucleotide sequences and gene organization. This has been shown for human and avian H3.3A and H3.3B genes and for a murine H3.3B cDNA. In an attempt to define patterns of replacement histone H3.3 gene expression during male germ cell differentiation, we have constructed mouse testicular cDNA libraries and have isolated cDNAs corresponding to the murine H3.3A and H3.3B genes. Using probes specific for these two different genes we show by RNase protection analysis and by nonradioactive in situ hybridization with testis sections that H3.3A mRNA is present in pre- and postmeiotic cells, whereas expression of the H3.3B gene is essentially restricted to cells of the meiotic prophase. PMID- 9373946 TI - A new spore differentiation factor (SDF) secreted by Dictyostelium cells is phosphorylated by the cAMP dependent protein kinase. AB - Upon starvation, Dictyostelium discoideum unicellular amoebae form a multicellular organism leading to the development of a fruiting body containing spores. Single cells of sporogenous mutants, unlike wild type cells, are able to differentiate into spores under specific conditions. We show in this report that overexpression of the catalytic subunit of the cAMP dependent protein kinase (PKA), not only renders the cells sporogenous, but is also accompanied by the production/release of a diffusible spore differentiation factor (SDF). SDF is a small, thermostable phospho-polypeptide. In vitro dephosphorylation reduces SDF spore differentiation capacity, which can be regained in vitro by PKA phosphorylation. These results indicate that SDF is a PKA substrate and might be activated in vivo by this protein kinase. Since spore differentiation requires PKA catalytic subunit activation, we conclude that the response of prespore cells to SDF involves an intracellular pathway dependent on PKA. PMID- 9373944 TI - Glucocorticoid receptor gene expression during rat embryogenesis. An in situ hybridization study. AB - Glucocorticoids play an important role in embryonic development. The existence of sufficient amounts of their receptors during rodent embryogenesis has proved to be an absolute necessity for the physiological growth of the animal. We have analyzed the pattern of glucocorticoid receptor gene expression in the rat embryo through embryonic days 12 to 17, by using in situ hybridization histochemistry. Glucocorticoid receptor mRNA is present in the rat liver on embryonic day (E) 12, and by E13 the signal can also be detected in several other tissues, such as the lung, the heart, the mesonephros, the sclerotomes, the thymus and Rathke's pouch. Glucocorticoid receptor gene expression was quite ubiquitous in tissue derivatives of all three germ layers and appeared to vary in intensity within the same tissue during embryogenesis. These variations in the level of receptor gene expression paralleled the developmental stage of each tissue: Intense labelling was detected just prior to the final differentiation step of a structure. Upon differentiation, cell populations highly expressing glucocorticoid receptor gene in the previous stage were found to have reduced amounts of the receptor mRNA. Our results support a morphogenetic role for glucocorticoids during embryogenesis. PMID- 9373945 TI - The human homeobox genes MSX-1, MSX-2, and MOX-1 are differentially expressed in the dermis and epidermis in fetal and adult skin. AB - In order to identify homeobox genes which may regulate skin development and possibly mediate scarless fetal wound healing we have screened amplified human fetal skin cDNAs by polymerase chain reaction (PCR) using degenerate oligonucleotide primers designed against highly conserved regions within the homeobox. We identified three non-HOX homeobox genes, MSX-1, MSX-2, and MOX-1, which were differentially expressed in fetal and adult human skin. MSX-1 and MSX 2 were detected in the epidermis, hair follicles, and fibroblasts of the developing fetal skin by in situ hybridization. In contrast, MSX-1 and MSX-2 expression in adult skin was confined to epithelially derived structures. Immunohistochemical analysis of these two genes suggested that their respective homeoproteins may be differentially regulated. While Msx-1 was detected in the cell nucleus of both fetal and adult skin; Msx-2 was detected as a diffuse cytoplasmic signal in fetal epidermis and portions of the hair follicle and dermis, but was localized to the nucleus in adult epidermis. MOX-1 was expressed in a pattern similar to MSX early in gestation but then was restricted exclusively to follicular cells in the innermost layer of the outer root sheath by 21 weeks of development. Furthermore, MOX-1 expression was completely absent in adult cutaneous tissue. These data imply that each of these homeobox genes plays a specific role in skin development. PMID- 9373947 TI - Physiological and biochemical characterization of intergeneric hybrids of thermotolerant and non-thermotolerant yeasts. AB - Kluyveromyces-like intergeneric hybrids of thermotolerant Kluyveromyces marxianus and non-thermotolerant Saccharomyces cerevisiae, produced in a previous study by protoplasmic fusion, have been characterized. On molasses, these strains produced ethanol in excess of 6% (v/v) both at 30 and 45 degrees C as against 3% and 4.2% (v/v) by the former parent at 30 and 45 degrees C, respectively. In hybrids, the increase in ethanol production appeared to be a sequel to increased activities of alcohol dehydrogenase and pyruvate kinase, derived probably from S. cerevisiae parent. Hybrid ADH-isozyme pattern on polyacrylamide gel corroborated the presence of S. cerevisiae ADH in the tested hybrids. Regression analyses indicated a positive correlation between ethanol production and ADH or PK or both (r approximately 0.76-0.84). PMID- 9373948 TI - Epizootic of Chlamydia psittaci infection in goats in Taiwan. AB - Epizootic abortion in goats has been frequently reported in Taiwan since 1993. The outbroken flocks were found in most of districts in Taiwan. No apparent clinical signs were found in aborted doe. The typical abortion occurred in the last two months of pregnancy. The incidence of abortion was from 10% to 87% in outbroken farms in 1993, and a total of 976 out of 2130 pregnancies (46%) were found abortion in our investigation. Gross lesions in aborted fetuses included generalized haemorrhage and swollen liver. Chlamydia psittaci was isolated from tissues of aborted fetuses and from vaginal swabs of aborted does. Chlamydial antibodies were detected among 67% to 100% of aborted does from epizootic flocks. The C. psittaci was diagnosed as the causal agent in enzootic abortion. This is the first report on chlamydial isolation and antibody surveys in epizootic abortion in goats in Taiwan. PMID- 9373949 TI - Genome instability and chromosomal rearrangements in a heterothallic wine yeast. AB - Wine strains of Saccharomyces cerevisiae are usually homothallic diploids and show chromosome length polymorphism. We describe the analysis of a heterothallic strain heterozygous for the mating types a and alpha. Surveying cultures of the strain, we found a remarkable degree of heterogeneity in ploidy and in electrophoretic karyotype. The CHEF analysis of tetrads and dyads revealed an enormous variability of band patterns hampering the analysis of chromosome segregation. We propose that the instability of ploidy and chromosome polymorphism might be due to heterothallism that precludes the process "genome renewal" (MORTIMER et al. 1994) by selfdiploidization of spore clones. PMID- 9373950 TI - The simultaneous production of both Hly- and Hpm-like hemolysins is characteristic of the Proteus penneri species. AB - Clinical isolates of Proteus penneri were tested for the presence of genes encoding hemolytic activity. Strains possessing DNA sequences similar to the hlyCABD genes in Escherichia coli were found. Each secreted a 110 kDa protein which reacted with a specific anti-HlyA antiserum. Southern blotting analysis revealed that the HindIII restriction fragment pattern for the hlyCABD genes of these strains was conserved. Similarly, the chromosomal location of these genes is relatively conserved based on the pattern of NotI digested DNA fragments separated by pulsed field gel electrophoresis. One strain carried an additional copy of the hlyCABD determinant which was mapped on a second NotI genomic fragment. All strains contained also chromosomally encoded sequences related to the hpmBA genes originally cloned from Proteus mirabilis. All strains produced a 166 kDa exoprotein detected in immunoblots with a specific antiserum raised against HpmA hemolysin. The hpmBA genes were located on other NotI fragments than hlyCABD genes. In contrast to the other Proteae, the simultaneous production of both hemolysins seems to be a common characteristics of Proteus penneri isolates. PMID- 9373951 TI - The effect of heparin on the activity of Trichosporon cutaneum casein kinase I. AB - Casein kinase I from Trichosporon cutaneum ribosome-free extracts was purified. Its molecular mass was calculated for 33 kDa. It was shown that casein, phosvitin and Trichosporon cutaneum ribosomal protein of 15 kDa were preferable substrates for the enzyme. It was found that heparin can stimulate or inhibit CKI activity depending on the substrate used. Stimulation of casein and inhibition of phosvitin phosphorylation was observed. In addition it was shown that ribosomal proteins of 19 kDa and 38 kDa were phosphorylated by CKI only in the presence of heparin. PMID- 9373952 TI - Nucleotide sequence of the Staphylococcus aureus transposon, Tn5405, carrying aminoglycosides resistance genes. AB - Tn5405 is a 12 kb staphylococcal composite transposon delimited by two inverted copies of the insertion sequence IS1182. This transposon carries two aminoglycosides resistance genes, aphA-3 and aadE, an altered gene similar to sat4 from Campylobacter coli BE/G4, and three open reading frames of unknown functions. PMID- 9373953 TI - Tympanic sound radiation in the bullfrog Rana catesbeiana. AB - Members of the Rana catesbeiana clade display sexually dimorphic eardrums. In this species assemblage the eardrum of males can be 50% larger than in females of the same body size. There has been, however, no apparent functional explanation for this dimorphism. Measurements of the acoustical coupling (transfer function) of internally generated sound to the enlarged eardrum of male bullfrogs (R. catesbeiana) show distinct energy peaks coincident with those observed in the spectral envelopes of the release and mating calls. Moreover, when the tympanic membranes are artificially damped the spectrum of the release call is drastically altered and the total amount of power radiated decreases substantially. These observations point to a previously unsuspected role for the ears in the sound broadcasting process of the bullfrog and possibly other anurans with similarly modified tympanic membranes. PMID- 9373954 TI - Bat-deafness in day-flying moths (Lepidoptera, Notodontidae, Dioptinae). AB - Assuming that bat-detection is the primary function of moth ears, the ears of moths that are no longer exposed to bats should be deaf to echolocation call frequencies. To test this, we compared the auditory threshold curves of 7 species of Venezuelan day-flying moths (Notodontidae: Dioptinae) to those of 12 sympatric species of nocturnal moths (Notodontidae: Dudusinae, Noctuidae and Arctiidae). Whereas 2 dioptines (Josia turgida, Zunacetha annulata) revealed normal ears, 2 (J. radians, J. gopala) had reduced hearing at bat-specific frequencies (20-80 kHz) and the remaining 3 (Thirmida discinota, Polypoetes circumfumata and Xenorma cytheris) revealed pronounced to complete levels of high-frequency deafness. Although the bat-deaf ears of dioptines could function in other purposes (e.g., social communication), the poor sensitivities of these species even at their best frequencies suggest that these moths represent a state of advanced auditory degeneration brought about by their diurnal life history. The phylogeny of the Notodontidae further suggests that this deafness is a derived (apomorphic) condition and not a retention of a primitive (pleisiomorphic), insensitive state. PMID- 9373955 TI - Number of preoptic GnRH-immunoreactive cells correlates with sexual phase in a protandrously hermaphroditic fish, the dusky anemonefish (Amphiprion melanopus). AB - The populations of gonadotropin-releasing hormone (GnRH)-producing cells within the preoptic area (POA) and terminal nerve (TN) of the brain have been suggested as the neuronal systems mediating social control of sex and gonadogenesis in sequentially hermaphroditic teleosts. In the present study, the number and soma size of GnRH-immunoreactive (GnRH-ir) cells in the POA and TN were studied in male, female and juvenile individuals of the dusky anemonefish (Amphiprion melanopus), a species which displays both male to female sex change and socially controlled sexual maturation. The results showed that the number of POA (but not TN) GnRH-ir cells differ significantly between sexual phases, with males displaying higher cell numbers than both females and juveniles. Soma sizes of POA and TN GnRH-ir cells were larger in females than in males and juveniles. However, this relationship was fully explained by differences in body size. The results indicate that high POA GnRH cell numbers are part of a masculinizing mechanism and support the hypothesis that the POA GnRH cell population plays a central role in initiating or mediating the process of socially induced gonadal and/or behavioural transformations in sequential hermaphrodites. PMID- 9373956 TI - Activity of long-wavelength cones under scotopic conditions in the cyprinid fish Danio aequipinnatus. AB - In carp (Cyprinus) and goldfish (Carassius), long-wavelength cones are reported to be active under scotopic conditions. Using the electroretinogram (ERG), we tested another cyprinid fish, Danio aequipinnatus, which contains A1-based visual pigments and for which we had previously measured the spectral sensitivities of individual cones. Dark adaptation curves show a rod/cone break at about 45 min. When thoroughly dark-adapted, the spectral sensitivity function is broader than can be accounted for by self-screening of rhodopsin, but it can be modeled by an additive combination of rods and the 560-nm cones. Dim, red background light causes adaptation of rods and a broadening of the spectral sensitivity function, which can be simulated by increasing the proportion of cones in the model. Brighter red backgrounds adapt the 560-nm cones. Because of the effect of red adapting lights, the ERG evidence for the participation of long-wavelength cones close to visual threshold appears to be different in Danio than in the goldfish Carassius. PMID- 9373957 TI - Seismic communication between the burrows of kangaroo rats, Dipodomys spectabilis. AB - Banner-tailed kangaroo rats, Dipodomys spectabilis, footdrum to produce substrate borne and airborne acoustic energy. Previous studies show that they communicate territorial ownership via airborne footdrumming signals. The research reported here used simulated footdrum patterns generated by an artificial 'thumper' to address the question of whether kangaroo rats communicate through seismic components of these acoustic signals. With microphones suspended in sealed burrows, we found that airborne sounds were attenuated by approximately 40 dB as they passed through the burrow wall into the burrow chamber. The substrate-borne vibrations from the thumper yielded sound approximately 40 dB greater in peak amplitude than the attenuated airborne sound. Thus, 99.9% of the peak power of the thumper was transmitted directly through the substrate into the burrow. The rats in sealed burrows timed their responses to playbacks of footdrums from the thumper and a loudspeaker so they did not initiate a drumming sequence during either the seismic or airborne signals. When these signals were masked by loud noise, the rats continued to drum to the seismic signal but drummed randomly during the airborne playback. These results suggest that the sealed burrow provides a quiet place in which D. spectabilis can listen for substrate-borne communications from conspecifics. PMID- 9373958 TI - Characterization and modeling of P-type electrosensory afferent responses to amplitude modulations in a wave-type electric fish. AB - The first stage of information processing in the electrosensory system involves the encoding of local changes in transdermal potential into trains of action potentials in primary electrosensory afferent nerve fibers. To develop a quantitative model of this encoding process for P-type (probability-coding) afferent fibers in the weakly electric fish Apteronotus leptorhynchus, we recorded single unit activity from electrosensory afferent axons in the posterior branch of the anterior lateral line nerve and analyzed responses to electronically generated sinusoidal amplitude modulations of the local transdermal potential. Over a range of AM frequencies from 0.1 to 200 Hz, the modulation transfer function of P-type afferents is high-pass in character, with a gain that increases monotonically up to AM frequencies of 100 Hz where it begins to roll off, and a phase advance with a range of 15-60 degrees. Based on quantitative analysis of the observed gain and phase characteristics, we present a computationally efficient model of P-type afferent response dynamics which accurately characterizes changes in afferent firing rate in response to amplitude modulations of the fish's own electric organ discharge over a wide range of AM frequencies relevant to active electrolocation. PMID- 9373959 TI - Non-covalent complexes between DNA-binding drugs and double-stranded deoxyoligonucleotides: a study by ionspray mass spectrometry. AB - The non-covalent complexes between some DNA-binding drugs and duplex oligodeoxynucleotides were studied by ionspray mass spectrometry, with the aim of evaluating the suitability of this technique to screen rapidly a series of drugs exerting their activity through non-covalent binding to specific base sequences of DNA. Two classes of drugs were considered, distamycins (which show affinity for the minor groove of DNA) and anthracyclines (which interact through intercalation between bases). For the former, d(CGCGAATTCGCG)2 was chosen as the model oligodeoxynucleotide. Following optimization of sample preparation and instrumental conditions, the complexes of different distamycins were observed; depending on the ligand considered, 1:1 or 2:1 complexes were formed preferentially. A semi-quantitative evaluation of the relative affinities was made by measuring the ratio of the complexes signals to those of the duplex, and also by competitive binding with equimolar amounts of distamycin. For anthracyclines, the daunorubicin-d(CGATCG)2 complex was chosen as the model for a preliminary mass spectrometric study; however, the signals of the duplex and the complex were very low compared with the monomer signal. Since the complex was known to be stable in solution, this was ascribed to gas-phase instability, probably caused by electrostatic repulsion between negatively charged phosphate groups. PMID- 9373960 TI - Determination of urinary acylcarnitines by ESI-MS coupled with solid-phase microextraction (SPME). AB - The determination of selected short-, medium- and long-chain acylcarnitines by electrospray ionization mass spectrometry (ESI-MS) is discussed. The differences in fragmentation behaviour and ionization efficiency are described in dependence on collision induced dissociation (CID) conditions and mixture composition. A new method combination, solid-phase microextraction (SPME)-ESI-MS, is introduced to characterize acylcarnitines in body fluids. This method utilizes SPME for pre concentration of acylcarnitines from complex biological samples and ESI-MS for a selective and sensitive detection. The method is presented by standard experiments determining of acylcarnitines in aqueous solutions and urine samples from patients with secondary carnitine deficiency syndromes or related disorders. PMID- 9373961 TI - Determination of dextromethorphan and dextrorphan in human plasma by liquid chromatography/tandem mass spectrometry. AB - Rapid, sensitive and selective methods were developed for the determination of dextromethorphan and its major metabolite, dextrorphan, in human plasma using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Plasma samples spiked with stable-isotope internal standards were prepared for analysis by a liquid liquid back-extraction procedure. Dextromethorphan and dextrorphan were chromatographed on a short reversed-phase column, using separate isocratic mobile phase conditions optimized to elute each compound in approximately 1.1 min. For both analytes, calibration curves were obtained over four orders of magnitude and the limit of quantitation was 5 pg ml-1 using a 1 ml plasma sample volume. The accuracy across the entire range of spiked DEX and DOR concentrations was, in general, within 10% of the spiked value. The precision was generally better than 6% for replicate sample preparations at levels of 50 pg ml-1 or higher and typically better than 12% at levels below 50 pg ml-1. The method was applied for the evaluation of the pharmacokinetic profiles of dextromethorphan and dextrorphan in a human volunteer following peroral administration of a commercially available cough formulation. PMID- 9373963 TI - Current literature in mass spectrometry. PMID- 9373962 TI - Gas chromatographic/mass spectrometric assay for profiling the enantiomers of 3,4 methylenedioxymethamphetamine and its chiral metabolites using positive chemical ionization ion trap mass spectrometry. AB - A qualitative GC/MS profile was obtained and its mass spectrometric features characterized for the analysis of the enantiomers of (RS)-3,4 methylenedioxymethamphetamine (MDMA) and its metabolites (RS)-3,4 methylenedioxyamphetamine (MDA), (RS)-4-hydroxy-3-methoxymethamphetamine (HMMA) and (RS)-4-hydroxy-3-methoxyamphetamine (HMA). A chiral derivatization method was selected to obtain the diastereomers required for the separation of the respective enantiomers with a non-chiral GC stationary phase. The selected derivatization consisted of a reaction with N-heptafluorobutyryl-(S)-prolyl chloride combined with a consecutive reaction with N-methyl-N trimethylsilyltrifluoroacetamide, resulting in N-[heptafluorobutyryl-(S)-prolyl] O-trimethylsilyl derivatives. Detection was carried out with electron ionization and positive chemical ionization (PCI) ion trap mass spectrometry. Mass spectra of the derivatives of reference standards of the compounds of interest obtained with PCI demonstrated that this method simultaneously induces proton and charge transfer reactions in the ion trap. The advantage is that high mass information is provided while some fragmentation remains to elucidate structural details. Subsequently, in three urine samples obtained from different and unrelated MDMA intoxications, the enantiomers of MDMA and MDA were identified. In some urine samples also HMMA and/or HMA were found. In addition to these compounds, an unexpected compound and/or additional chiral metabolite, N-hydroxy-(RS)-3,4 methylenedioxyamphetamine, was identified in two out of three urine samples. Preliminary results also indicated an enantioselective metabolism in the N demethylation pathway for MDMA in humans. PMID- 9373968 TI - Nonlinear distortion of short pulses radiated by plane and focused circular pistons. AB - Detailed measurements of finite-amplitude pulses radiated by plane and focused circular pistons in water are presented. Comparisons of time waveforms and frequency spectra, both on and off axis, are made with numerical calculations based on the nonlinear parabolic wave equation. Emphasis is on nonlinear distortion of amplitude- and frequency-modulated tone bursts. Use of short pulses enabled resolution of the direct and diffracted waves prior to their coalescence and subsequent shock formation along the axis of the source. Because of its relevance to investigations of cavitation inception, attention is devoted to variation of the peak positive (p+) and negative (p-) pressures along the axis of a focused source. It is shown that with increasing source amplitude, the maximum of each shifts away from the focal plane, toward the source. This effect is more pronounced for p- than for p+. PMID- 9373966 TI - Development of the Xenopus laevis VIIIth cranial nerve: increase in number and area of axons of the saccular and papillar branches. AB - Development of three branches of the VIIIth cranial nerve was examined in the anuran, Xenopus laevis. Sectioned tissue from the saccular, amphibian papillar, and basilar papillar branches of stage 52 larvae, 1 day postmetamorphosis juveniles, and 2-year adult animals was analyzed under the light microscope with a digital image analysis system. Numbers and cross-sectional areas of myelinated axons were measured in five to six nerve sections at each developmental age for each of the three branches. In all three branches, results show a significant increase in axon numbers between larval stage 52 and juvenile ages and negligible increase in axon number between the juvenile and adult ages. There were differences in the average number of axons between the saccular (704.4 +/- 39.5; n = 5), amphibian papillar (508.4 +/- 35.0; n = 5), and basilar papillar (316.0 +/- 7.0; n = 5) branches of adult animals. Myelinated axons increase at an estimated rate of 11.7, 15.1, and 6.2 axons per day for the saccular, amphibian papillar, and basilar papillar branches, respectively. Axonal cross-sectional areas increased throughout the developmental ages of this study, with the greatest increase taking place between juvenile and adult ages. In adult animals, 98% of axons in all three branches have diameters between 2-10 microns. Ratios of axons to hair cells in adult animals were estimated at 0.3, 1.1, and 5.3 for the sacculus, amphibian papilla, and basilar papilla, respectively. The higher axon to hair cell ratio correlates with the increasing acoustical frequency sensitivity of the end organ. PMID- 9373969 TI - Acoustic field prediction for a single planar continuous-wave source using an equivalent phased array method. AB - Phased array theory is combined with the Rayleigh-Sommerfeld diffraction integral to predict measured acoustic fields generated by a single-source ultrasonic transducer. The idea is to treat a single-source as a "phased array," which is composed of many small elements. The goal is to find the excitation source for the phased array, that is, the amplitude and phase for each array element, which produces an acoustic field similar to the experimentally measured field generated by the single-source transducer. A pressure field measured at a given plane parallel and close to the face of the transducer in degased water was used to calculate the excitation source of the equivalent phased array using an inverse technique. The excitation source of the equivalent phased array was then used to calculate the acoustic field from this measurement plane to the far field. It was demonstrated that this phased array approach accurately predicted the location of major grating lobes and the general distributions of the near and far pressure fields for four different transducers. This equivalent phased array method (EPAM) used to model a single-source transducer should be useful in both diagnostic and therapeutic ultrasound applications. PMID- 9373970 TI - Audible circuit noise in hearing aid amplifiers. AB - Audible electronic circuit noise generated within a hearing aid is distracting to a listener in quiet situations and, if the noise level is high enough, may cause listener irritation and rejection of the hearing aid. Thus for hearing aid specification and fitting purposes, it is useful to know the acoustic levels at which this internal noise may become audible and also at which it may become objectionable. For hearing aid amplifier circuit specification and design purposes, it is useful to know the same levels in electrical terms. This paper reports on a study that used an amplifier with no acoustic input and a hearing aid receiver output to simulate internally generated hearing aid circuit noise. Results are reported for testing eight subjects with high-frequency hearing loss for the perceived acoustic and electrical levels at which internal circuit noise became both audible and objectionable. PMID- 9373971 TI - Spontaneous otoacoustic emission frequency is modulated by heartbeat. AB - Detailed analysis of spontaneous otoacoustic emissions (SOAEs) in human subjects revealed that all stable SOAEs sufficiently above the noise floor to permit appropriate analysis have sidebands at multiples of approximately 1 Hz. This is consistent with the hypothesis that SOAEs are modulated by heartbeat. Simultaneous measurement of the rate of blood flow to the thumb and the separation of the spectral sidebands demonstrated that they covary (r = 0.982, p < 5 x 10(-10)). An adaptive least-squares fit (LSF) paradigm was developed to facilitate the measurement of the instantaneous frequency and amplitude of the signals. A combination of traditional spectral analyses and new LSF analyses showed that the sideband generation stems from frequency modulation of the emissions. If there is any amplitude modulation correlated with the blood flow, it is below the noise floor of the analysis. The frequency of the emission was at a minimum when the blood flow was maximal. Examination of alternative mechanisms using computer simulations suggests that these changes stem from changes of 10 100 ppm in the mass of the basilar membrane. PMID- 9373972 TI - Otoreflectance of the cochlea and middle ear. AB - Otoreflectance refers to acoustic pressure reflectance measurements in the ear canal, by the use of a leak-free insertion of a probe assembly, in the frequency or time domain over a range of two or more stimulus levels. Otoreflectance includes an iso-level response indicative of the forward transfer of acoustic energy into the middle ear, and nonlinear responses indicative of the acoustic energy reflected back from the cochlea. The nonlinear otoreflectance decouples the reflected energy in an evoked otoacoustic emission (OAE) from its subsequent re-reflected energy due to the presence of the ear-canal probe. Nonlinear otoreflectance responses are extremely sensitive to probe distortion, and a double-evoked (2E) technique, previously used in evoked (OAE) measurements, is adapted for otoreflectance to solve the distortion problem. Results are obtained using a 2E stimulus set containing a set of three click stimuli delivered through a pair of sources. The corresponding sets of three pressure responses are acquired in a calibration tube, and in the ear canal, and a set of three iso level ear-canal reflectances is calculated. An evoked OAE can be decomposed into a otoacoustic reflected pressure (ORP), and a nonlinear otoreflectance is defined by the ratio of the ORP to the initial pressure spectrum. Otoreflectance provides simultaneous measurements of middle-ear and cochlear responses, and has potential, as yet untested, for application to clinical tests for hearing impairments. PMID- 9373973 TI - Basic characteristics of click-evoked otoacoustic emissions in infants and children. AB - Since Kemp [J. Acoust. Soc. Am. 64, 1386-1391 (1978)] first described click evoked otoacoustic emissions (COAEs), researchers have advocated their use as an excellent tool for diagnosing hearing loss in infants and children. However, there are few detailed reports of COAEs in this population, and those that do exist suggest that there are age-dependent differences. The purpose of the current study was to determine basic characteristics of COAEs in infants, toddlers, children, and young adults and to define any differences among age groups. An additional goal was to ensure that spontaneous otoacoustic emissions (SOAEs) did not confound any possible developmental effects. COAEs and SOAEs were measured from one ear of 223 normal-hearing subjects. COAE input/ output functions indicated that children aged less than one year have higher COAE levels than older children and adults. Children aged 1-5 yr had higher COAE levels than those aged 12-17 yr and adults. These differences were independent of level and SOAE status, but were dependent on frequency. The results of this study suggest that different clinical norms may be necessary for children aged less than 6 years. PMID- 9373974 TI - Basic characteristics of distortion product otoacoustic emissions in infants and children. AB - Distortion-product otoacoustic emissions at the 2 f1-f2 frequency (DPOAEs) are being advocated as a clinical tool for diagnosis of peripheral auditory pathology. Because they can be measured quickly and noninvasively, they may be an excellent method for identifying hearing loss in infants and children. However, few studies have examined the characteristics of DPOAEs in infants and children or detailed if, and how, their responses differ from those of adults. The purpose of the current study was to determine basic characteristics of DPOAEs in infants, toddlers, children, and young adults and to define any differences among age groups. An additional goal was to ensure that the presence of spontaneous otoacoustic emissions (SOAEs) did not confound any developmental effect. DPOAE input/output (I/O) functions at seven f2 frequencies and SOAEs were measured from one ear of 196 subjects. Children aged less than 1 yr had significantly higher mean DPOAE levels than older children and adults, and children aged 1-3 yr had higher mean DPOAE levels than teens and adults. These differences were dependent on frequency but were independent of f2 level and SOAE status. At every f2 frequency, groups of individuals having SOAEs had higher mean DPOAE levels than those not having SOAEs. PMID- 9373975 TI - Measurement of distortion product phase in the ear canal of the cat. AB - Amplitudes of odd order distortion products (DPs) that are detected in animal ear canals have been used to probe cochlear health, to search for cochlear amplification, and to measure aspects of cochlear mechanical frequency response. Like the DP amplitude, DP phase is also an important measure of the cochlear mechanical response. Reported here are measurements of DP phase in the ear canal of the cat. The phase data show frequency-dependent time delays. One of these delays is a function of f2, the frequency of the higher-frequency primary. Hence the DP phase phi d is of the form phi d = phi 0 + omega d tau, where omega d is the DP angular frequency and tau is a fixed time delay. Our results show that phi d is independent of input level a2 as long as the ratio a2/a1 < or = 2, where a2 and a1 are the amplitudes of the input tones. As a2/a1 becomes greater than two, the fixed time delays increase for DPs whose frequencies are less than the frequencies of the input tones. When both levels are varied together the delay increases as the levels decrease. There can be phase changes as large as pi associated with deep nulls in the DP magnitude for the two lower-frequency DPs. Features of the nulls may be modeled assuming that there is partial reflection of the DP wave from the DP place. The assumption of energy remitted from the DP place also explains amplitude-ratio-dependent time delays and 2 pi level dependent bifurcations in phase. The DP phase shows different dependencies for f2 < 1 kHz compared to f2 > 2 kHz. PMID- 9373976 TI - Modeling auditory processing of amplitude modulation. I. Detection and masking with narrow-band carriers. AB - This paper presents a quantitative model for describing data from modulation detection and modulation-masking experiments, which extends the model of the "effective" signal processing of the auditory system described in Dau et al. [J. Acoust. Soc. Am. 99, 3615-3622 (1996)]. The new element in the present model is a modulation filterbank, which exhibits two domains with different scaling. In the range 0-10 Hz, the modulation filters have a constant bandwidth of 5 Hz. Between 10 Hz and 1000 Hz a logarithmic scaling with a constant Q value of 2 was assumed. To preclude spectral effects in temporal processing, measurements and corresponding simulations were performed with stochastic narrow-band noise carriers at a high center frequency (5 kHz). For conditions in which the modulation rate (fmod) was smaller than half the bandwidth of the carrier (delta f), the model accounts for the low-pass characteristic in the threshold functions [e.g., Viemeister, J. Acoust. Soc. Am. 66, 1364-1380 (1979)]. In conditions with fmod > delta f/2, the model can account for the high-pass characteristic in the threshold function. In a further experiment, a classical masking paradigm for investigating frequency selectivity was adopted and translated to the modulation frequency domain. Masked thresholds for sinusoidal test modulation in the presence of a competing modulation masker were measured and simulated as a function of the test modulation rate. In all cases, the model describes the experimental data to within a few dB. It is proposed that the typical low-pass characteristic of the temporal modulation transfer function observed with wide band noise carriers is not due to "sluggishness" in the auditory system, but can instead be understood in terms of the interaction between modulation filters and the inherent fluctuations in the carrier. PMID- 9373977 TI - Modeling auditory processing of amplitude modulation. II. Spectral and temporal integration. AB - A multi-channel model, describing the effects of spectral and temporal integration in amplitude-modulation detection for a stochastic noise carrier, is proposed and validated. The model is based on the modulation filterbank concept which was established in the accompanying paper [Dau et al., J. Acoust. Soc. Am. 102, 2892-2905 (1997)] for modulation perception in narrow-band conditions (single-channel model). To integrate information across frequency, the detection process of the model linearly combines the channel outputs. To integrate information across time, a kind of "multiple-look" strategy, is realized within the detection stage of the model. Both data from the literature and new data are used to validate the model. The model predictions agree with the results of Eddins [J. Acoust. Soc. Am. 93, 470-479 (1993)] that the "time constants" associated with the temporal modulation transfer functions (TMTF) derived for narrow-band stimuli do not vary with carrier frequency region and that they decrease monotonically with increasing stimulus bandwidth. The model is able to predict masking patterns in the modulation-frequency domain, as observed experimentally by Houtgast [J. Acoust. Soc. Am. 85, 1676-1680 (1989)]. The model also accounts for the finding by Sheft and Yost [J. Acoust. Soc. Am. 88, 796-805 (1990)] that the long "effective" integration time constants derived from the data are two orders of magnitude larger than the time constants derived from the cutoff frequency of the TMTF. Finally, the temporal-summation properties of the model allow the prediction of data in a specific temporal paradigm used earlier by Viemeister and Wakefield [J. Acoust. Soc. Am. 90, 858-865 (1991)]. The combination of the modulation filterbank concept and the optimal decision algorithm proposed here appears to present a powerful strategy for describing modulation-detection phenomena in narrow-band and broadband conditions. PMID- 9373978 TI - Detection and discrimination of frequency glides as a function of direction, duration, frequency span, and center frequency. AB - The study investigated the ability to detect and discriminate frequency glides under a variety of experimental conditions. The subjects distinguished between a comparison signal that either was level in frequency or was swept across a fixed frequency span, and a target signal that changed more in frequency than the comparison signal. Tone durations were 50 and 400 ms. Nominal center frequencies were 0.5, 2, and 6 kHz; actual center frequencies were varied randomly, or roved, over a range equal to 0.1 times the nominal center frequency. Up- and down-glides were used. The transition span of the comparison signal was either 0, 0.5, 1, or 2 times the equivalent rectangular bandwidth of the auditory filter at the nominal center frequency. Discrimination thresholds were obtained for all combinations of center frequency, direction, and span. Overall, thresholds expressed as delta Hz/ERB varied little as a function of center frequency. Glide duration had no effect on discrimination. The 50-ms down-glides were more difficult to detect than the 50-ms up-glides; otherwise, the effect of direction was not significant. With the exception of the 50-ms down-glides, detection/discrimination thresholds were similar for the 0-, 0.5-, and 1-ERB transition spans, but increased significantly for the 2-ERB span. The absence of significant variation across frequency supports a place mechanism for the detection of frequency change in gliding tones, based on the detection of changes in the excitation pattern. An excitation pattern model cannot account for the asymmetry noted for glide detection, however. PMID- 9373979 TI - Loudness of dynamic stimuli in acoustic and electric hearing. AB - Traditional loudness models have been based on the average energy and the critical band analysis of steady-state sounds. However, most environmental sounds, including speech, are dynamic stimuli, in which the average level [e.g., the root-mean-square (rms) level] does not account for the large temporal fluctuations. The question addressed here was whether two stimuli of the same rms level but different peak levels would produce an equal loudness sensation. A modern adaptive procedure was used to replicate two classic experiments demonstrating that the sensation of "beats" in a two- or three-tone complex resulted in a louder sensation [E. Zwicker and H. Fastl, Psychoacoustics-Facts and Models (Springer-Verlag, Berlin, 1990)]. Two additional experiments were conducted to study exclusively the effects of the temporal envelope on the loudness sensation of dynamic stimuli. Loudness balance was performed by normal hearing listeners between a white noise and a sinusoidally amplitude-modulated noise in one experiment, and by cochlear implant listeners between two harmonic stimuli of the same magnitude spectra, but different phase spectra, in the other experiment. The results from both experiments showed that, for two stimuli of the same rms level, the stimulus with greater temporal fluctuations sometimes produced a significantly louder sensation, depending on the temporal frequency and overall stimulus level. In normal-hearing listeners, the louder sensation was produced for the amplitude-modulated stimuli with modulation frequencies lower than 400 Hz, and gradually disappeared above 400 Hz, resulting in a low-pass filtering characteristic which bore some similarity to the temporal modulation transfer function. The extent to which loudness was greater was a nonmonotonic function of level in acoustic hearing and a monotonically increasingly function in electric hearing. These results suggest that the loudness sensation of a dynamic stimulus is not limited to a 100-ms temporal integration process, and may be determined jointly by a compression process in the cochlea and an expansion process in the brain. A level-dependent compression scheme that may better restore normal loudness of dynamic stimuli in hearing aids and cochlear implants is proposed. PMID- 9373980 TI - The perception of frequency peaks and troughs in wide frequency modulations. IV. Effects of modulation waveform. AB - This work extends previous studies on the perceptual asymmetry between the local maxima and minima of wide frequency modulations (FMs) [L. Demany and K. I. McAnally, J. Acoust. Soc. Am. 96, 706-715 (1994); L. Demany and S. Clement, J. Acoust. Soc. Am. 97, 2454-2459 (1995); L. Demany and S. Clement, J. Acoust. Soc. Am. 98, 2515-2523 (1995)]. In experiment 1, subjects had to discriminate frequency shifts in the temporally central vertex of V- and A-shaped FMs imposed on 200-ms sinusoidal tone bursts. The precise shapes of these FMs varied in eight steps from quasi-triangles (with a durationless central vertex) to quasi-squares (with a long-duration central vertex). The central vertex was either a minimum or a maximum, but in each case the corresponding frequency was near 1000 Hz and the FM span was about 0.5 oct. For each FM shape, the discrimination threshold was lower when the vertex was a maximum than when it was a minimum, but (in four subjects out of five) this difference decreased monotonically as the FM became less and less triangular. FM shape had a remarkably small effect on the discrimination of the maxima, and the thresholds measured for the sharpest maxima were unexpectedly low. In subsequent experiments, subjects had to discriminate frequency shifts in the starting point or the final point of unidirectional FMs (tone glides) that spanned about 0.5 oct in 100 ms. The relevant frequency extremum was near 1000 Hz in each condition. At the final point of the glides, discrimination was better for rising glides than for falling glides. At the starting point of the glides, discrimination was better for falling glides than for rising glides. Thus discrimination was always better when the relevant frequency extremum was a maximum than when it was a minimum, and this effect was produced both "forward" and "backward." The latter fact suggests that the perceptual asymmetry of FM originates at least partly from central factors. PMID- 9373981 TI - Organization and discrimination of repeating sound sequences by newborn infants. AB - A study was conducted to determine whether newborn infants organize auditory streams in a manner similar to that of adults. A series of three experiments investigated the ability of 3- to 4-day-old infants to discriminate repeated rising and falling four-tone sequences in two configurations of source timbre and spatial position. It was hypothesized that if the sequences were organized into two auditory streams on the basis of timbre and spatial position, one of the configurations should be discriminable from its reversal while the other should not. The sequences were tested with different pitch and temporal intervals separating the tones. Sequences were discriminated for the first configuration by adults at both fast tempo/small interval and slow tempo/large interval combinations, while only the latter was discriminated by newborns as measured with a non-nutritive high-amplitude sucking paradigm. Neither adults nor infants could discriminate the sequence reversals for the second configuration. The results suggest that newborn infants organize auditory streams on the basis of source timbre and/or spatial position. They also suggest that newborns have limits in temporal and/or pitch resolution when discriminating tone sequences. PMID- 9373982 TI - Detection of increments and decrements in sinusoids as a function of frequency, increment, and decrement duration and pedestal duration. AB - Thresholds for the detection of increments and decrements in level of 70 dB SPL sinusoidal signals were measured as a function signal duration (10, 20, or 200 ms), pedestal duration before the signal (10 ms, 200 ms, or pedestal on continuously) and frequency (250, 1000, or 4000 Hz). The sinusoids were presented in a low-pass filtered background noise with an overall level of 68-69 dB SPL which had two purposes: (1) to mask spectral splatter; (2) to induce an adaptation effect, which caused the continuous 4000-Hz pedestal (but not the other two pedestals) to decay to inaudibility (adaptation). We were particularly interested in determining whether the difference in noise-induced adaptation across frequency would influence the pattern of results. Seven normal-hearing subjects were used. Thresholds improved with increasing frequency and with increasing duration for both increments and decrements. However, the effect of increment/decrement duration decreased with increasing frequency; at 4000 Hz thresholds were almost the same for increment durations of 10 and 20 ms. The energy of the increments at threshold increased markedly with increasing increment duration (especially from 20 to 200 ms), suggesting a dominant role for the onsets of the increments as opposed to ongoing differences in level. Increasing the pedestal duration before the increment from 10 to 200 ms slightly improved thresholds for increment and decrement durations of 10 and 20 ms. Increment thresholds were similar for the gated and continuous pedestals at all frequencies, even though the 4000-Hz continuous pedestal decayed to inaudibility. However, thresholds for 200-ms increments were somewhat lower for continuous than for gated pedestals, and supplementary experiments found a larger gated continuous difference for pedestals presented in quiet. Making the pedestal continuous adversely affected performance for the 10- and 20-ms decrements, but not for the 200-ms decrement. We suggest that the results for decrement detection may be affected by neural long-term adaptation, although they are not clearly related to loudness adaptation. PMID- 9373983 TI - Binaural detection with spectrally nonoverlapping signals and maskers: evidence for masking by aural distortion products. AB - Thresholds were measured for diotic tonal signals in the presence of interaurally delayed bands of Gaussian noise. When the signal frequency was 525 Hz., the spectrum of the noise was either below (highest frequency, 450 Hz) or above (lowest frequency, 600 Hz) the frequency of the signal. When the signal frequency was 450 Hz, the spectrum of the noise was always above the signal frequency (lowest frequency, 600 Hz). Signals had a 250-ms duration and were temporally centered within the 300-ms long bursts of noise. The spectrum level of the noise was 60 dB. Thresholds obtained in all three conditions varied essentially sinusoidally with the interaural delay of the noise. For signals below the spectrum of the noise, the periodicities within the data were close to, but not identical with, the periodicities of the signals. This outcome is discussed in terms of masking produced by aural distortion products stemming from interactions within the bands of noise [cf. van der Heijden and Kohlrausch, J. Acoust. Soc. Am. 98, 3125-3134 (1995)]. For signals above the spectrum of the noise, the periodicities in the data suggested that masking was produced by components within the band of noise. Patterns within the data are also discussed in terms of limitations concerning the magnitude of external delays that can be matched by internal delays that are incorporated in modern models of binaural processing. PMID- 9373984 TI - Cross-spectral and temporal factors in the precedence effect: discrimination suppression of the lag sound in free-field. AB - In an anechoic chamber, subjects were required to discriminate a 20 degrees azimuthal change in a lag sound's position in the presence of a lead sound coming from a different direction. Delay between lead and lag sounds was adaptively varied in several conditions to track discrimination suppression thresholds. In experiment 1, lead and lag stimuli were 5-ms, 1-octave, A-weighted noise bursts (65 dB), with lead and lag parametrically set to center frequencies of 0.5, 2.0, or 3.0 kHz. Discrimination suppression thresholds were higher when lead and lag center frequencies coincided (mean: 11.3 ms) than when they did not coincide (mean: 2.9 ms). These results support the "spectral overlap hypothesis" of Blauert and Divenyi [Acustica 66, 267-274 (1988)], but not the "localization strength hypothesis" later proposed by Divenyi [J. Acoust. Soc. Am. 91, 1078-1084 (1992)]. Spectral overlap and localization strength appear to be two relatively independent factors governing discrimination suppression. It is proposed here that localization strength is weighted more when stimuli are presented via headphones and the only cue to lateral position is the interaural temporal difference, while spectral overlap is weighted more for free-field presented stimuli. In experiment 2, lead and lag stimuli were 8-ms, 1.5-kHz A-weighted tone bursts (65 dB), with lead and lag rise times parametrically set to 0, 2, or 4 ms. In this case the amount of discrimination suppression increased as lead rise time became more abrupt or as lag rise time became more gradual. These results support the localization strength hypothesis: The greater the localization strength of the lead stimulus (independently assessed by measuring its minimum audible angle in isolation), the greater suppression it exerted on discriminability of the lag sound's position. It appears that for stimuli presented in the free-field, spectral overlap is the primary factor affecting discrimination suppression, but when overlap is held constant, abruptness of stimulus onsets governs the amount of suppression. PMID- 9373985 TI - Effects of three parameters on speaking fundamental frequency. AB - Speaking fundamental frequency levels and usage (SFF, F0) are of interest to many investigators who study human speech and voice. Substantial research in the area has been carried out; common foci include SFF as related to infant cry, age, gender, adolescent voice change, language, race, voice pathology, and so on. Yet there still are a number of relationships which are not well understood and three of them will be addressed in this project. They involve the long-held notions that (1) a secular trend exists with SFF being lowered over time, (2) the use of university students in research of this type will create bias because they are physically different from average individuals, and (3) SFF can vary systematically for different types of speech (especially for oral reading and extemporaneous speaking). Experiments assessing these questions were carried out, but only certain of the postulates were supported. That is, while some evidence of a secular trend was found, it appeared inconsequential during the past quarter of this century; second, although university students were found to be slightly larger than a cohort approaching the average population, only minor vocal differences were found. Finally, it was observed that, in general, oral reading resulted in higher mean SFF's than those for spontaneous speech. However, this difference was not robust and, due to reversals, the resulting metric did not appear to be of good predictive value for individual speakers. PMID- 9373986 TI - Simulating the effect of cochlear-implant electrode insertion depth on speech understanding. AB - Normally hearing listeners were presented with vowels, consonants, and sentences for identification through an acoustic simulation of a five-channel cochlear implant with electrodes separated by 4 mm (as in the Ineraid implant). The aim of the experiment was to simulate the effect of depth of electrode insertion on identification accuracy. Insertion depth was simulated by outputting sine waves from each channel of the processor at a frequency determined by the cochlear place of electrodes inserted 22-25 mm into the cochlea. The results indicate that simulated insertion depth had a significant effect on performance. Performance at 22- and 23-mm simulated insertion depths was always poorer than normal, and performance at 25 mm simulated insertion depth was, most generally, the same as normal. It is inferred from these results that, if insertion depth could be unconfounded from other coexisting factors in implant patients, then insertion depth would be found to affect speech identification performance significantly. PMID- 9373987 TI - The perceptual relevance of locus equations. AB - Identification curves were estimated for the English consonants /b,d,g/ using five-formant CV synthetic stimuli comprehensively sampling the F2 onset-F2 vowel acoustic space in the vicinity of /b,d,g/ locus equations [H. Sussman et al., J. Acoust. Soc. Am. 90, 1309-1325 (1991)]. The stimuli included 10 English monophthongal vowel contexts, 11 levels of F2 onset per vowel, and 3 levels of F3 onset orthogonally varied with the F2 variables (10 vowels x 11 F2 onsets x 3 F3 onsets = 330 stimuli). After brief training, each of six subjects, three male and three female, was presented eight trials of each of the stimuli, one or two trials per day over a period of several days. Systems of identification curves were visualized as identification surfaces situated in locus equation acoustic space and were overlaid with acoustic data from five male speakers in order to judge the degree of correspondence between perception and acoustic data. A chi square analysis was also performed in order to quantify the correspondence between the observed perception data and expected frequencies derived from the acoustic data. The results, when interpreted in terms of a dominance hierarchy hypothesis, strongly indicate F2 onset and F2 vowel, in combination, serve as important cues for stop consonant place of articulation. PMID- 9373988 TI - The perceptual prominence of fundamental frequency peaks. AB - Five perception experiments were conducted that investigated how the perceived prominence of F0 maxima in accented syllables in Dutch is affected by the variation of F0 minima that is supposed to relate to variation in global pitch range. The purpose of the first two experiments was to test the predictions of a model in which the reference line is directly given by an interpolation between observable F0 minima. The results showed that the model was inadequate, and confirmed earlier research suggesting that the reference line is calculated in a less direct way. The next three experiments investigated the role of the F0 of the unaccented portions of speech at the beginning ("onset") and at the end ("offset") of the contour, and show that only the (low) onset is used to calibrate the reference line. The results also suggest that longer onsets affect the abstract reference more than do shorter onsets. PMID- 9373989 TI - Multielement concentrations in vegetable species grown in two typical agricultural areas of Greece. AB - The multielement (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, V, Zn) levels in various common vegetables and surface soils collected from two typical growing areas of north-western Greece are presented. The results are representative and indicate metal concentration levels in vegetables grown in Greek areas under similar conditions. The content of the metals is generally at the same levels or even lower than that reported for vegetables consumed in several countries and species grown in other agricultural and industrial Greek areas. Enhanced levels of metals observed in certain vegetable species could be related to their concentration in the corresponding soils. The results of the present study indicate that the mean intake of heavy metals (As, Cd, Pb and Se) by adults due to consumption of vegetables from the two sites, for an average consumption, pattern, generally is well below the allowable daily intakes. On the other hand, the contribution of the vegetables to the recommended amounts of the essential elements (Cu, Fe, Mn and Zn) is satisfactory and higher than previously reported. PMID- 9373990 TI - Normal human intrathyroidal iodine. AB - Excessive or deficient iodine intake results in a variety of human thyroid dysfunction and disorder. The main part in the etiology of these disorders relates to the concentrations of intrathyroidal iodine which is important to regulate thyroid function and state. Instrumental neutron activation and X-ray fluorescent analyses were used to study the age dynamics of intrathyroidal iodine. Concentration and the total content of iodine in the thyroid were estimated in necropsy samples of 70 men and 20 women aged 2-87. Both thyroid lobes were weighed, lyophilised and homogenised. Iodine was analysed in approximately 50-mg samples. The mean intrathyroidal iodine concentration (mean +/- S.E.) of a normal subject aged 26-65 averaged 345 +/- 21 micrograms g-1 dry tissue in non-endemic goitre region with no obligatory salt iodination. Maximum iodine concentration was found to be 494 +/- 65 micrograms g-1 (P < 0.05) for the age of 16-25. A statistically reliable second increase of iodine was shown for the elderly which was 668 +/- 60 micrograms g-1 (P < 0.001) for the age over 65. Human intact thyroid weight for the age over 15 does not change and averages 14.2 +/- 0.4 g. Both left and right lobes of intact thyroid do not differ in weight, iodine concentration and the total content. An inverse correlation was found between thyroid weight and intrathyroidal iodine concentration (-0.32, P < 0.01). The range of intrathyroidal iodine parameters is wide enough to provide a possible explanation for the particular sensitivity of some population to both excessive and deficient iodine intake. Similarity of intrathyroidal iodine age dynamics and incidence of new cases of thyroid carcinoma were to confirm the hypothesis of intrathyroidal iodine importance in cancer etiologies suggested before. PMID- 9373991 TI - Spatial and temporal patterns of acidity and heavy metals in predicting the potential for ecological impact on the Le An river polluted by acid mine drainage. AB - Integration and comparison of metal contamination from acid mine drainage and an assessment of the potential for ecological impact was conducted in the aquatic ecosystems of the Le An river. The results indicated low acidity, high levels of suspended solids containing a high content of copper in river water and sediment in the upstream region of the Le An river due to the pollution from the Dexing copper mine, and high concentrations of zinc and copper in surface water and sediments, high release potential and ready bioavailability of heavy metals in sediments downstream (after site A07) due to the pollution from the Jishui river. The pollution from acid mine drainage in the Le An river potentially effects an ecological impact on the aquatic ecosystem, mainly between sites A04 and A08. The management strategy should, therefore be mainly applied to acid mine drainage from the Dexing copper mine and heavy metal discharges from the Jishui river. PMID- 9373992 TI - OH-radical-type reactive oxygen species: a short review on the mechanisms of OH radical- and peroxynitrite toxicity. PMID- 9373994 TI - Regulation of a NAD+ kinase activity isolated from asynchronous cultures of the achlorophyllous ZC mutant of Euglena gracilis. AB - NAD+ kinase was isolated by chromatography steps from asynchronous cultures of the achlorophyllous ZC mutant of Euglena gracilis. A non Ca(2+)-calmodulin dependent form whose activity was stimulated by EGTA, was selected for its large quantity and high specific activity. Studies of the kinetic parameters revealed two kinds of NAD+ binding site, depending on NAD+ concentrations, and changes induced by EGTA, Ca2+ and Ca(2+)-calmodulin. The search for effectors, soluble (S) and membrane-bound (P), in Euglena gracilis synchronously grown (in a light dark regime of 12h:12h), and collected at circadian times (CT)--corresponding to the maximum, CT 17, and to the trough, CT 09, of the circadian rhythm of NAD+ kinase activity--was also undertaken by testing the modulations of the kinetic parameters of the prepared NAD+ kinase. The results suggest: (i) structural changes of NAD+ binding sites depending on NAD+ concentrations; (ii) possible binding of the Mg-ATP-2 (or Ca-ATP-2) on the NAD+ sites, because of their common ADP motif; and (iii) different and specific modulations of the kinetic parameters of the two types of NAD+ binding site by the Ca(2+)-calmodulin complex. In addition, the results indicate, in pelletable fractions isolated at CT 09 and CT 17, the presence of two kinds of effector:(i) the first one, possibly Ca2+, which increases the Vmax's while decreasing the binding of NAD+; (ii) the second one, possibly the Ca(2+)-calmodulin complex, which provokes a complete reverse effect. Each of these two effectors seems to be, alternatively and rhythmically (eight circadian hours apart), partially released from the membranes. PMID- 9373993 TI - Blue light mediated photoreduction of the flavoprotein NADPH-cytochrome P450 reductase. A Forster-type energy transfer. AB - The absorption spectra and the corresponding molar absorption coefficients of the fluorophores umbelliferone, FAD and FMN and of the FAD and FMN containing flavoprotein NADPH-cytochrome P450 reductase of different oxydation-reduction states are documented. Binding spectra of the ligand umbelliferone with the CYP2B1:NADPH-cytochrome P450 reductase-complex were determined by difference spectroscopy. The Scatchard plot of the equilibrium ligand binding shows a high affinity part and a low affinity part of 12 and 34 umbelliferone binding sites per CYP2B1:reductase-complex molecule, respectively. The fluorescence excitation and emission spectra of the donor molecule umbelliferone and the acceptor molecules FAD and FMN are given. The fluorescence spectra of the reaction components under test conditions of CYP2B1-dependent 7-ethoxycoumarin-O deethylase are measured. The excitation energy transfer from the donor umbelliferone (lambda E = 380 nm; lambda F = 460 nm) to the acceptor molecule FMN (lambda E = 465 nm; lambda F = 525 nm) was examined under assay conditions. The results demonstrate that a radiationless Forster-type energy transfer takes place in the presence of the CYP2B1:reductase-complex. It turned out that this effect is a function of the protein complex-concentration. The data presented here combined with previously made observations by Muller-Enoch (Muller-Enoch D. (1994), Z. Naturforsch. 49c, 763-771) support the finding that the umbelliferone molecules, n = 12-34, bound per mole of CYP2B1:reductase-complex, transfer their absorbed light energy radiationless to the FAD binding domain. The complex formed containing 12 or 34 molecules of umbelliferone provides absorption coefficient values at lambda = 380 nm of 78 and 221 mM-1.cm-1, respectively. The Forster-type energy transfer from the donor umbelliferone to the acceptor FAD not only leads to a light activation of the singlet state of FAD but also to a conformational change of the amino acids close to the FAD binding side to favour the encaging of the FAD* triplet state which reacts with the NADPH to form the FADH2 reductase. Due to this process the overall reaction can start with the unquenched excited FAD* triplet state as an intermediate which is about 30 kJ/mol lower in energy than the dark reaction. PMID- 9373995 TI - Structural differences of ovalbumin and S-ovalbumin revealed by denaturing conditions. AB - We found, by circular dichroism and Raman spectroscopy measurements, that the secondary structure of the native ovalbumin and of its heat-stable form, called S ovalbumin, is a probe of the structural differences between the two proteins. Small angle X-ray scattering and circular dichroism measurements performed on the two proteins under denaturing conditions, with different concentrations of guanidine hydrochloride, show the changes of the tertiary and secondary structure and a different pathway in the unfolding process. These experimental data confirm that the conversion of native ovalbumin into S-ovalbumin is irreversible and reveal that the response of the two proteins to the same chemical environment is different. PMID- 9373996 TI - The activity of thymidine phosphorylase obtained from human uterine leiomyomas and studied in the presence of pyrimidine derivatives. AB - Partially purified samples of thymidine phosphorylase were obtained from four preparations of human uterine leiomyomas and uteri using the method of Yoshimura et al. (1990), Biochim. Biophys. Acta 1034, 107-113. Among the studied twelve pyrimidine derivatives, 5-bromouracil, 5-nitrouracil, 5-fluorouracil, 6 aminouracil, 4, 6-dihydroxy-5-nitropyrimidine are competitive inhibitors, while allyloxymethylthymine is an uncompetitive inhibitor of thymidine phosphorylase activity, 6-benzyl-2-thiouracil inhibits the activity of the enzyme in a mixed way. The most potent inhibitor of the thymidine phosphorylase activity is 5 bromouracil and uracil the weakest one. Stronger inhibition of these compounds on the activity of thymidine phosphorylase was found in uterine leiomyomas than in uteri. PMID- 9373997 TI - Comparative effects of scopoletin and aflatoxin B1 on bovine hepatic mitochondrial respiration in vitro. AB - A comparative study of the in vitro effects of the coumarin compounds, scopoletin and aflatoxin B1 (AFB1), on bovine (Bos indicus) hepatic mitochondrial respiration was carried out polarographically, using isocitrate -NAD+ (3 - site), succinate (2 - site), and reduced cytochrome c (1 - site), as respiratory substrates. Both scopoletin and AFB1 elicited a substrate--dependent stimulation or inhibition of the mitochondrial states 4 and 3 respiration. The results suggest that AFB1 has a higher tendency to inhibit the mitochondrial respiration than scopoletin, while scopoletin showed higher uncoupling effects than AFB1. The effects of scopoletin and AFB1 on mitochondria were more pronounced on the electron transport than on phosphorylation reaction. The extent (3-35%) of AFB1 induced inhibition of bovine mitochondrial respiration observed in this study, was appreciably lower than the values indicated in other animal species (rats and guinea fowls) reported in previous studies using equivalent concentrations of the toxin. These results were discussed in terms of the susceptibility of the animal species to the toxic effects of scopoletin and AFB1. PMID- 9373998 TI - Uterine relaxant effect of zolpidem: a comparison with other smooth muscle relaxants. AB - Zolpidem is an imidazopyridine sedative-hypnotic which interacts with central benzodiazepine-receptors. To examine its effects on uterine smooth muscle we have compared with those obtained by diltiazem, papaverine and diazepam on different experimental models. The IC50 values obtained indicate similar behaviour of zolpidem and diazepam. They showed more active against the spontaneous contractions and those induced by KCl (60 mM) or by CaCl2 (0.01-10 mM) in Ca(2+) free depolarizing medium than against acetylcholine (0.1 mM)-induced contractions. Both of them also showed more effectiveness against the tonic component of the acetylcholine-evoked contraction than against the phasic one. All the drugs tested were less powerful against contractions induced by oxytocin than against those induced by other agonists. This observation let us speculate that the mechanism of action of zolpidem may be related to an action on Ca2+ influx through voltage-dependent Ca2+ channels due to an interaction with low affinity receptor located at the plasmalemma as has been suggested for diazepam. PMID- 9373999 TI - Reaction of hypochlorous acid with bovine nasal cartilage comparison to pig articular cartilage. AB - The action of sodium hypochlorite (NaOCl) on bovine nasal cartilage was studied by proton nuclear magnetic resonance (1H-NMR) spectroscopy in order to model degradation processes of cartilage caused by neutrophil-derived hypochlorous acid. Nasal cartilage was chosen as a mean of comparison because it differs from articular cartilage in its composition. It contains some more proteoglycans, i.e. polymeric carbohydrates and less collagen than articular cartilage. This is important for studying the influence of hypochlorous acid on cartilage components (collagen and polysaccharides). Cartilage samples were incubated at 37 degrees C with phosphate buffer in the presence or absence of NaOCl. Supernatants were collected and assayed by NMR-spectroscopy. In the presence of pure phosphate buffer, the supernatants of bovine nasal cartilage were less rich in low molecular mass metabolites (e.g. amino acids, lactate) than articular cartilage. However, intense signals for highly mobile N acetyl groups of cartilage polysaccharides were detectable in nasal cartilage. NaOCl caused an increase in signals for acetate and formiate. Signals for N-acetyl groups rose only during the first 25 minutes of incubation with NaOCl. Then, their concentration decreased markedly. These changes were related to an enhanced release of chondroitinsulfate from nasal cartilage. PMID- 9374000 TI - Isolation and characterization of cytotoxic diterpenoid isomers from propolis. AB - The methanol extract of Brazilian propolis was fractionated by HPLC, based on HuH13 (human hepatocellular carcinoma) cell cytotoxicity assay. Two isomers of diterpenoid with a molecular formula of C20H30O3 (MW: 318.46) were isolated. The structures of these colorless compounds were determined as clerodane diterpenoids (I, 15-oxo-3, 13Z-kolavadien-17-oic acid; II, 15-oxo-3Z, 13E-kolavadien-17-oic acid). PMID- 9374001 TI - Addiction, ethics and public policy. AB - Addiction affects the lives of all of human kind, either directly or indirectly. The cost to individuals and societies is immense and tackling the problem is as much one for policy makers as clinicians, counsellors and scientists. Ethical issues permeate much of the work of all these groups. The issue of what is right and wrong, morally defensible or morally unacceptable arises at both an individual and societal level. This special issue contains 21 commissioned articles from leading figures in addiction research. To set the scene for these in-depth analyses, this article reports the results of an expert panel survey on addiction, ethics and public policy. A total of 199 people from 24 countries identified as first authors of research papers abstracted in Addiction Abstracts in 1994 and 1995 completed a postal questionnaire asking their views on a range of issues. They were asked to state their position on the issue and to identify what they considered to be the most important factors in the decision. Among the findings of interest were: a majority believed that possession of cannabis should be legal but that possession of 'hard drugs' should be illegal. An overwhelming majority believed that tobacco advertising should be banned, that smoking should be prohibited in public buildings and offices and that the legal age for tobacco sales should be 18 or more. A majority believed that researchers should not accept backing from tobacco companies; opinion on accepting backing from the alcohol industry was more evenly divided. An overwhelming majority believed that drug addicts should be able to attend treatment centres on demand and that some form of methadone maintenance should be available to addicts who want it. The survey should prove a useful resource when debating the issues in policy and research arenas. PMID- 9374002 TI - Tobacco research funded by the tobacco industry--an ethical conflict. AB - What moral misgivings may arise in connection with the financing of research? Does the source of the funds for a research project matter? Tobacco exemplifies this problem well. Tobacco smoking is the largest single cause of illness and premature death in the industrialized world, but the tobacco industry is also one of its most profitable commercial undertakings. Decades of increasing scientific evidence for the harmfulness of smoking have increased the moral pressure on manufacturers. Good relations with the scientific community is a desirable way to demonstrate the legitimacy of their operations. Medical researchers should act in accordance with the classical ethical principles of medicine; autonomy, doing good, justice and doing no harm. The activities of the tobacco manufacturing companies are not in accordance with these principles. Every medical researcher or physician who uses funding from the tobacco companies cannot escape the fact of lending his or her name to the manufacture of a lethal product. PMID- 9374003 TI - Buying research. AB - Doubts have been raised in the popular press about the credibility and desirability of alcohol research funded by the industry. In this paper, it is asserted that little independent, empirical research is available on the effects commercial sponsorship has on the research topic and outcome. The author proposes further research in this area that would be helpful in clearing the menaces of unwanted funding practices. It is suggested to draw up guidelines or rules of conduct similar to those that are being developed in, particularly, pharmacological research, an area that is highly dependent upon sponsorship by commercial industry. PMID- 9374004 TI - Protecting the interests of participants in research into illicit drug use: two case studies. AB - This paper addresses the conflict between the ethical and legal responsibilities of researchers engaged in illicit drug use research. Fundamentally, the primary ethical responsibility is to protect research subjects from any harm which may come to them as a consequence of having taken part in the research. Legal responsibilities, however, might lie in assisting police with their enquiries into the conduct of an individual who is a research subject, and allowing research data to be searched and possibly used in evidence against the individual. There is no Western Australian legislation which protects research, nor Australian legislation which can be applied to most studies. Using two case studies, we give examples of the conflict and suggest that legislation may be the most effective way to overcome it. However, we also raise a number of issues which would need to be considered before solutions are enacted. PMID- 9374005 TI - Ethical, scientific and clinical issues in ethanol administration research involving alcoholics as human subjects. AB - Research involving the administration of ethanol to human subjects has been conducted with some regularity since the 1960s. The purpose of this paper is to provide a broader discussion of the ethical and clinical issues pertaining to the administration of ethanol to subjects with a history of alcohol dependence and to assess the potential benefits and risks of ethanol administration research. Three kinds of investigation are reviewed: (1) basic scientific research on alcohol dependence and related disabilities; (2) clinical research that involves ethanol administration as part of the treatment; and (3) studies that have evaluated the short- and long-term effects of ethanol administration on the health and wellbeing of alcoholic research participants. It is concluded that ethanol administration research has not only contributed to the fund of knowledge about basic mechanisms of alcohol dependence; it has also advanced the scientific understanding of treatment. Moreover there is no compelling evidence that participation in ethanol administration research per se has adverse effects on alcoholic research subjects. In the interests of developing a practical approach to the ethical dilemmas posed by ethanol administration research, an ethical review process is suggested that takes into account the principles of respect for people, beneficence, and justice by tailoring the risk/benefit analysis to four types of research subjects: alcoholics recruited directly from the community, subjects recruited from residential treatment settings, recovering alcoholics, and alcoholics in outpatient treatment. PMID- 9374007 TI - The recent Australian debate about the prohibition on cannabis use. AB - This paper outlines the ethical arguments used in the Australian debate about whether or not to relax the prohibition on cannabis use by adults. Over the past two decades a rising prevalence of cannabis use in the Australian population has led to proposals for the decriminalization of the personal use of cannabis. Three states and territories have removed criminal penalties for personal use while criminal penalties are rarely imposed in the remaining states. Libertarian arguments for legalization of cannabis use have attracted a great deal of media interest but very little public and political support. Other arguments in favour of decriminalization have attracted more support. One has been the utilitarian argument that prohibition has failed to deter cannabis use and the social costs of its continuation outweigh any benefits that it produces. Another has been the argument from hypocrisy that cannabis is less harmful than alcohol and so, on the grounds of consistency, if alcohol is legally available then so should cannabis. To date public opinion has not favoured legalization, although support for the decriminalization of personal cannabis use has increased. In the long term, the outcome of the debate may depend more upon trends in cannabis use and social attitudes among young adults than upon the persuasiveness of the arguments for a relaxation of the prohibition of cannabis. PMID- 9374006 TI - Confidentiality, disseminated regulation and ethico-legal liabilities in research with hidden populations of illicit drug users. AB - An assurance of confidentiality is at the core of trusting relationships in outreach, ethnographic research and patient/client encounters. In the past, centralized State health care services have provided assurances of confidentiality to those engaged in health-related research either through common law or by statute. However, unless specific confidentiality legislation is in place, no assurances of confidentiality can now be made to research subjects involved in either longitudinal, interview-based or ethnographic research. The consequences of this situation become more serious given the recent emergence of the use of peer and community outreach. A significant problem with the outreach model is the failure to provide adequate legal and ethical support for those in outreach roles. Additionally, unless research subjects can be granted assurances of confidentiality, they will not engage in research for fear of later prosecution. At this time when outreach models are the modus operandi, the lack of a fundamental commitment to sustain confidentiality may seriously undermine further research. This paper will draw on the experiences of some Australian qualitative research and will review some of the ethical and legal liabilities for research that arise when an assurance of confidentiality cannot be given to those participating in research. PMID- 9374008 TI - Ethics of alcohol policy in a saturated society. AB - Alcohol policy in modern society has been embedded in three of its great ideals: progress, individualistic universalism and nationalism. The total consumption theory and the idea of the public good have been the culmination of modern thinking in the prevention of alcohol problems. The modern ideals have today become achieved. Saturated modernity has led from a political society to a mass society, in which modern sociological theories are powerless, and ethical reflection is required. Two contradicting moral resources offer themselves: the ethics of the rule and the culture of authenticity. The modernist idea of the public good is related to the ethics of the rule but its viability is questioned. The Durkheimian idea that ethical decisions are inherently social is suggested as a solution. PMID- 9374010 TI - Mandated AA attendance for recidivist drinking drivers: policy issues. AB - Mandates for recidivist drinking drivers to attend AA meetings raise concerns about whether AA referral practices could have an adverse impact on both alcohol problems and traffic safety, whether routine and unregulated referrals to AA may prove detrimental to AA as an organization, and over ethical issues and possible loss of civil liberties. Similar issues arise in criminal justice and other agencies' handling of a variety of situations beyond the DUI arena. As a result institutions mandating involvement in mutual aid programs such as AA, and a variety of treatment settings, should adopt cautious referral practices, support rigorous research and create and evaluate targeted programs and integrated services. PMID- 9374009 TI - Influencing physician response to prenatal substance exposure through state legislation and work-place policies. AB - Little research attention has focused on ways to encourage physician response to prenatal substance exposure. We report initial results from a study examining the impact of state laws and work-place policies on physician response by combining legal analyses and data from a national physician survey. Our findings indicate that the message that laws and policies exist usually does not reach physicians. However, when the message does come through, some physician behaviors are influenced. In particular, physicians in states with clearer policies and behavioral expectations are significantly more likely to know and understand the law than physicians in other states. Further, believing that a work-place protocol on prenatal substance exposure exists is associated with significantly increased likelihood of an active response in case vignettes portraying prenatal substance exposure. The findings suggest that state legislative behaviors may increase physician response to prenatal substance exposure, but that response depends on the nature of the policy and on efforts to disseminate it. PMID- 9374011 TI - Ethical dilemmas in providing tobacco to developing countries: the case of China. AB - We should recognize that we have a responsibility to people who live outside our own borders, and view ourselves as part of the global community. Looking at China we are faced with ethical dilemmas which require consideration. First, there is the ethical dilemma of business versus health. The opening and development of the tobacco business in China, which includes vigorous marketing, is considered against the health consequences of tobacco use which is estimated to cost 600,000 lives annually in China, rising to 2 million by 2,025 without effective tobacco control programmes. A second ethical dilemma is employment versus impoverishment, in which the opportunities for work in the tobacco industry are considered against a background of malnutrition caused in part by a proportion of household budgets used to buy tobacco, and the erosion of the land, as trees are used to produce tobacco. Gains have already been made in tobacco control in China, with the way open for much development in the future. PMID- 9374013 TI - The path to Australia's tobacco health warnings. AB - Australia introduced new health warnings and contents labelling on cigarettes and other tobacco products from January 1995. The changes were based on recommendations emerging from research commissioned for that purpose. The research demonstrated the need for changes that changes could increase the noticeability of the warnings and contribute to an increase in relevant knowledge, and that the changes were acceptable to the public. The tobacco industry fought the changes and some modifications resulted, but new stronger warnings with elaborations on the back of the pack, an information number to call and elaborated contents labelling have been implemented. PMID- 9374012 TI - Setting goals for drug policy: harm reduction or use reduction? AB - Historically, United States drug policy has focused on use reduction; harm reduction is a prominent alternative. This paper aims to provoke and inform more debate about the relative merits of these two. Since harm is not necessarily proportional to use, use reduction and harm reduction differ. Both terms are somewhat ambiguous; precisely defining them clarifies thinking and policy implications. Measures associated with use reduction goals are poor; those associated with harm reduction are even worse. National goals influence the many decentralized individuals who collectively make drug policy; clearly enunciating goals makes some policy choices transparent and goals serve a variety of purposes besides guiding programmatic decisions. We recommend that the overall objective be to minimize the total harm associated with drug production, distribution, consumption and control. Reducing use should be seen as a principal means of attaining that end. PMID- 9374014 TI - Unintended consequences and professional ethics: criminalization of alcohol and tobacco use by youth and young adults. AB - This paper describes how widespread legal changes appear to have affected law enforcement practices concerning youth tobacco and alcohol use in the United States. We argue that the threat of criminalization was seldom addressed in scientific and public policy discussions of the drinking age, and only sporadically addressed in discussions of measures to regulate youth access to tobacco. We argue that unintended consequences are an important ethical issue for professionals involved in advocating, developing, implementing and evaluating public policy concerning substance abuse. PMID- 9374015 TI - The conflict between least harm and no-use tobacco policy for youth: ethical and policy implications. AB - This paper examines policy and ethical implementation issues associated with local drug policies that are aimed at producing a "least harm" approach toward youth, with particular application to tobacco policy as an example of a legal, but addictive drug. Research is reviewed which shows the inconsistencies between federally mandated enforcement of zero tobacco use, the Synar Amendment and local community and school policies which appear to relax enforcement of no-use policies for the purpose of retaining youth in school. The inconsistencies are described from the perspective of a "least harm" approach, in that tobacco use may be considered less harmful than absence from school, or use of other substances. The conflict between law and intent to reduce harm is examined with implications for long-term enforcement of federal policy, and for effectiveness of tobacco and other drug abuse prevention programs and other drug policies. Several strategies for reducing the conflict are recommended. These include provision of support-orientated smoking cessation programs for youth on school campuses and in community organizations, and promoting consistent no-use norms across all drugs and across multiple channels that affect youth-mass media, school, point-of-purchase settings and public settings and events. PMID- 9374016 TI - The new public health: nanny in a new hat? AB - It has been suggested that the new public health is but nannyism in a different guise and that its advocates are the equivalents of health fascists. It will be argued that a form of paternalism (or maternalism) has always been inherent in public health and that to treat illness as if it was wholly a personal possession is to abdicate the government's responsibility for ensuring a healthy environment. PMID- 9374017 TI - Opportunity costs of drug prohibition. AB - Psychoactive substances have benefits as well as risks. The benefits foregone by people who obey prohibition laws (as well as the costs of enforcing those laws against actual and would-be users) should be acknowledged when considering the ethics of drug policies. Older or terminally ill people, who would most likely benefit from psychological or spiritual insights, currently have less access to psychoactive substances than younger people who tend to use the substances for entertainment. The principle of distributive justice suggests that law-abiding citizens should not disproportionately suffer the opportunity costs of unenforceable policies of prohibition. A positive alternative policy would allow adult citizens access to certain psycoactive substances, comparable in safety and effectiveness to drugs now prescribed for medical purposes, as a valued resource for self-actualization. PMID- 9374018 TI - Responsibility for crime and injury when drunk. AB - The aim of this paper is to highlight the complexity in the connection between alcohol intoxication and responsibility for crime from a multidisciplinary approach comprising medical, legal and criminological perspectives. There is no doubt that there is a connection between violent behaviour and alcohol intoxication. However, several investigations show that alcohol heightens aggressiveness only when the drunken person is provoked. A case which may serve as a model when discussing legal responsibility for acts carried out when drunk is outlined. Ethical considerations are discussed and exemplified concerning the motive, as well as the principles, of punishing an intoxicated perpetrator. However, there are no definite solutions concerning what is right or wrong, and each reader will have his own opinion, which may well differ from that of the author. PMID- 9374019 TI - Denying treatment to drug and alcohol-dependent patients. AB - There has been a concerted move in the West to reduce health care expenditure and multiple moves have been made to achieve these cost reductions. Many approaches have been taken including the restriction of services to subsets within the population. Drug and alcohol dependent patients have often been targeted as individuals and as groups who should not be seen as having equal access to certain forms of therapy. In this article it is argued that many of these decisions are inappropriate and in many instances they are not based on evidence which suggests that patients who are dependent may do just as well as non dependent patients with some forms of treatment. It is argued that clinicians should regard each individual patient separately and make decisions that are appropriate to the clinical setting rather than taking a policy decision to restrict treatment to dependent individuals. PMID- 9374020 TI - The distribution of naloxone to heroin users. AB - Overdose deaths are a major contributor to excess mortality among heroin users. It has been proposed that opioid overdose morbidity and mortality could be reduced substantially by distributing the opioid antagonist naloxone to heroin users. The ethical issues raised by this proposal are evaluated from a utilitarian perspective. The potential advantages of naloxone distribution include the increased chance of comatose opioid users being quickly resuscitated by others present at the time of an overdose, naloxone's safety and its lack of abuse potential. The main problems raised by the proposal are: the medico-legal complications of medical practitioners prescribing a drug that is most likely to be administered to and by people other than the one for whom it is prescribed; the economic costs of distributing naloxone sufficiently widely to have an impact on overdose morbidity and mortality; and the potentially greater cost effectiveness of simpler educational interventions. Given the possible benefits of naloxone distribution, it may be worthwhile considering a controlled trial of naloxone distribution to high-risk heroin users. PMID- 9374021 TI - Substance abuse and maternity: the United States as a case study. AB - Two themes pervade the issue of women and addiction in the United States: anger and blame directed at women who use alcohol and other drugs; and neglect and a consequent lack of appropriate treatment. Often the focus is on the addicted pregnant woman and the debate posits a woman's right to autonomy and privacy in opposition to the future child's right to be born free from harm. Others emphasize the tension between blaming individuals and holding the state accountable for provision of services. These conflicts have impeded the diagnosis of women with substance abuse problems, the availability of services and women's access to appropriate care. PMID- 9374022 TI - Harm reduction: roads less travelled to the holy grail. AB - In recent years, a number of countries have embraced harm reduction as their principal philosophical stance and policy platform on alcohol and other drug related problems. Harm reduction, while argued by some as not being a new concept, has dramatically changed the overall orientation of many health and human service approaches. We argue that as a result many important considerations have been overlooked. This paper explores the merits of harm reduction and examines the limitations and potential pitfalls that may exist in its application in the real world. For instance, where do we position non-drug-use? Such questions are raised in light of the impression perpetuated by some leading practitioners in this field that harm reduction is a global panacea for alcohol and drug problems. Without exploring all possible paths, progress toward our holy grail of minimising the harms and maximising the potential benefits of drug use will be hampered. An integrated model is discussed, which we believe provides an opportunity for wider acceptance and ownership by alcohol and drug stakeholders, politicians and the community. PMID- 9374024 TI - Application of a novel fluorescence probe in the determination of nucleic acids. AB - A novel fluorimetric method has been developed for rapid determination of DNA and RNA with hypocrellin A (HA) as a fluorescence probe, based on the fluorescence enhancement of HA in the presence of DNA or RNA. Maximum fluorescence is produced in the pH range 3.4-4.0, with maximum excitation and emission wavelengths at 470 and 600 nm, respectively. Under optimal conditions, the calibration graphs are linear over the range 0-200.0 ng cm-3 for calf thymus DNA and 13.0-200.0 ng cm-3 for yeast RNA, respectively. The corresponding detection limits are 5.0 ng cm-3 for calf thymus DNA and 13.0 ng cm-3 for yeast RNA. The relative standard deviation of six replicate measurements is 4.5% for 100 ng cm-3 calf thymus DNA. DNA could be determined in the presence of 20% m/m yeast RNA. The mechanism for the binding of HA to DNA is also studied. PMID- 9374025 TI - Determination of dimetridazole in poultry tissues and eggs using liquid chromatography-thermospray mass spectrometry. AB - A method is presented for the determination of the nitroimidazole drug dimetridazole (DMZ) in poultry tissues and eggs by liquid chromatography (LC) thermospray mass spectrometry (MS). Deuteriated DMZ was employed as an internal standard. Samples were extracted with dichloromethane (muscle) or toluene (liver, egg) and applied to silica gel cartridges. Dimetridazole was eluted with acetone and the eluate evaporated to dryness at 40 degrees C under nitrogen. The residue was redissolved in methanol-water (1 + 1, v/v) and washed with hexane before LC MS analysis. Quantification was by the ratios of the positive [M + H]+ ions at m/z 142 and 145 for DMZ and the internal standard, respectively. Internal standard corrected recoveries were between 93 and 102% with RSDs between 1.2 and 7.7% for liver spiked at 5, 10 and 20 ng g-1 and muscle and eggs spiked at 5 ng g 1. Absolute recoveries were approximately 80%. The method is suitable for statutory residue testing and was used to measure DMZ residues in eggs from chickens fed a diet containing DMZ at 10 mg kg-1. PMID- 9374023 TI - Microfabricated flow chamber for fluorescence-based chemistries and stopped-flow injection cytometry. AB - A microfabricated flow chamber (MFC) suitable for performing liquid-based fluorimetric assays is introduced. Precision delivery of microliter volumes of sample and reagent to the MFC is accomplished by a double-syringe-pump flow injection analysis (FIA) apparatus. The FIA-MFC system also combines the 'sheath flow' technique (traditionally used in flow cytometry) and stopped-flow FIA as a way to allow sample and reagent streams to be mixed reproducibly. The applicability of this FIA-MFC system to bioanalytical assays is demonstrated by performing an enzymatic assay with an artificial fluorigenic substrate to determine the activity of Savinase, a proteolytic enzyme. When coupled to a fluorescence microscope platform, quantitative analysis of the reaction product is possible. Experiments showed that the FIA-MFC system was capable of performing the assay with good reproducibility of injection (1.5%), and linearity of response (r2 = 0.9997) in activity ranges of analytical interest. Owing to the incorporation of flow cytometry sheath flow principles into an FIA format, the FIA-MFC system is a suitable tool for cytometric studies. PMID- 9374026 TI - Determination of the quaternary ammonium compounds dequalinium and cetylpyridinium chlorides in candy-based lozenges by high-performance liquid chromatography. AB - The retention behavior of the quaternary ammonium compounds benzalkonium chloride, cetylpyridinium chloride and dequalinium chloride on a 100 x 4.6 mm id cyanopropyl stationary phase column is reported as a function of organic modifier and ionic hydrophobic mobile phase additive concentrations. Optimum liquid chromatographic mobile phases using different mobile phase additives are reported which are suitable for the determination of cetylpyridinium chloride and dequalinium chloride in a variety of candy-based lozenge formulations. The quantitative aspects of assays based on the separation of active ingredients and formulation excipients were established. The generality of application of the assay methods was evaluated by determining the quaternary ammonium content of different lozenges and comparing the values obtained with the stated dose. PMID- 9374027 TI - Bixin and norbixin in human plasma: determination and study of the absorption of a single dose of Annatto food color. AB - A procedure was developed for the detection and determination of bixin and norbixin in human plasma by reversed-phase HPLC with a sensitivity limit of 5 micrograms l-1. A group of seven volunteers ingested a single dose of 1 ml of a commercial Annatto Food Color (16 mg of cis-bixin in soybean oil). The presence of bixin (cis and trans) and norbixin (cis and trans) was demonstrated in the plasma at average levels of 11.6, 10.1, 2.8 and 0 micrograms l-1 of bixin and 48, 58, 53 and 29 micrograms l-1 of norbixin after 2, 4, 6 and 8 h, respectively. Considerable individual variations were observed. Complete plasma clearance generally occurred for bixin by 8 h and for norbixin by 24 h after ingestion of cis-bixin. PMID- 9374028 TI - Overoxidized poly(pyrrole-co-[3-(pyrrol-1-yl)-propanesulfonate])-coated platinum electrodes for selective detection of catecholamine neurotransmitters. AB - The cation-exchange and anion-exclusion properties of the poly?pyrrole-co-[3 (pyrrol-1-yl)propanesulfonate]?-(PPy-PS) copolymer are exploited for imparting higher selectivity to measurements of primary neurotransmitters in the presence of ascorbic acid. Such incorporation of ionizable sulfonated groups in the pyrrole ring prior to its electropolymerization leads to effective rejection of the anionic ascorbate species and preferential collection of the cationic dopamine and norepinephrine. Overoxidized PPy-PS films thus offer better discrimination against ascorbic acid than Nafion or overoxidized polypyrrole coatings. Experimental variables influencing the permselective behavior of the PPy-PS layer, including the electropolymerization time and solution pH, were explored. The selectivity and sensitivity improvements associated with the increased electrostatic character of overoxidized polypyrrole films hold promise for neurochemical electrochemical studies. PMID- 9374029 TI - Adsorptive stripping voltammetry of bleomycin. AB - In 0.05 M H2SO4 solution, two reductive peaks, P1 and P2, of bleomycin were obtained. The peak potentials E(P1) and E(P2) were -0.83 and -1.09 V (versus Ag/AgCl), respectively. The sensitivity of P2 was much higher than that of P1. The peak current of P2 was proportional to the concentration of bleomycin over the range 1.0 x 10(-9)-1.0 x 10(-7) M with a detection limit of 5.0 x 10(-10) M using adsorptive voltammetry at an accumulation time of 120 s (Ei = -0.80 V). The behaviour of the reduction wave was studied and applied to the determination of bleomycin in mouse serum. The reduction process of P1 was irreversible with adsorptive characteristics and the adsorption behavior obeyed the Frumkin adsorptive isotherm. The adsorptive coefficient beta was 8.9 x 10(5), the interaction factor alpha was 0.94 and the Gibbs energy of adsorption delta G degree was -33.93 kJ mol-1. P2 was an irreversible adsorption peak with catalytic hydrogen properties. PMID- 9374030 TI - Apoptosis: an overview. PMID- 9374031 TI - The bcl-2 family of proteins. AB - The bcl-2 family of proteins play an important role in the control of apoptosis. Family members exist which are either pro- or anti-apoptotic and their activity appears to control a checkpoint between signals from the cell surface and activation of the ICE-family of proteases. Despite having a key role to play in apoptosis, the mechanism of action of these proteins can only, at present, be inferred due to the lack of understanding about their biological activity. However, some general principles can be gleaned from the large body of published work to suggest what are likely to be the best directions for future endeavour. PMID- 9374032 TI - The caspase family of cysteine proteases. AB - The discovery that CED-3, the product of a gene necessary for programmed cell death in the nematode Caenorhabditis elegans, is related to the mammalian cysteine protease interleukin-1 beta converting enzyme (ICE/caspase-1) has led to intense interest in the role of proteases in apoptosis. It is now clear that at least some members of the caspase (ICE/CED-3) family, which at present includes ten homologues of human origin, are essential components of an evolutionarily conserved pathway of apoptosis. These enzymes appear to be involved in both the initial signaling events and the downstream proteolytic cleavages that result in the apoptotic phenotype. Selective macromolecular and peptide-based inhibitors attenuate apoptosis in whole cells, suggesting that one or more of these enzymes will be suitable targets for therapeutic intervention in diseases resulting from inappropriate cell death. PMID- 9374033 TI - Recognition and phagocytosis of cells undergoing apoptosis. AB - In vivo, the normal fate of cells undergoing apoptosis is recognition, uptake and degradation of the intact dying cell by phagocytes. Cell clearance by this mechanism is fast, efficient and injury-limiting, being mediated by macrophages and semi-professional phagocytes. Apoptotic cells are marked for disposal by mechanisms which remain poorly understood, although in some circumstances surface sugar changes and exposure of phosphatidylserine lead to recognition by uncharacterised phagocyte receptors. Furthermore, there is specific evidence in vitro for involvement of phagocyte receptors including the thrombospondin receptors alpha v beta 3 and CD36, scavenger receptors, the 61D3 antigen and the ABC 1 transporter. It is conceivable that recognition mechanisms may be ordered in a hierarchy of 'back ups', each recognising cells at different stages of the death program. Nevertheless, a full understanding of this complexity will require definition of recognition mechanisms which operate in vivo in higher organisms. PMID- 9374034 TI - Viruses and apoptosis. AB - Virus infection and replication are often associated with apoptosis and this effect is likely to be responsible for much of the pathology associated with infectious disease. Many viruses encode proteins which can inhibit apoptosis thereby either prolonging the survival of infected cells such that the production of progeny virus is maximised or facilitating the establishment of virus persistence. These viral proteins target the cellular pathways responsible for regulating apoptosis and have been instrumental in furthering our understanding of the apoptotic process. Many of the viruses associated with oncogenic transformation have adopted strategies for blocking apoptosis highlighting the centrality of this effect in carcinogenesis. Understanding the mechanisms by which viruses regulate apoptosis may lead to the development of novel therapies for both infectious disease and cancer. PMID- 9374035 TI - p53 and apoptosis. AB - Loss of function of the p53 tumour suppressor gene is a frequent and important event in the genesis or progression of many human malignancies. Loss of p53 dependent apoptosis is believed to be critical to carcinogenesis in many of these cases, suggesting the possibility to therapeutically restore this pathway and directly eliminate malignant cells or increase or restore their sensitivity to chemotherapeutic agents. The regulation of p53-dependent responses is complex and variable between cell types, and whether a cell undergoes apoptosis after activation of p53 is highly sensitive to signal context, including environmental and cell intrinsic influences. This article focuses upon p53-dependent apoptosis, considering current understanding of the biochemical steps involved, the factors determining selection of apoptosis over other p53-dependent responses, the significance of p53-dependent apoptosis for the genesis, progression and drug resistance of human cancers, and finally the prospects for clinical manipulation of this pathway in cancer therapy. PMID- 9374036 TI - Ceramide signaling in apoptosis. AB - The sphingomyelin pathway is a ubiquitous, evolutionarily conserved signaling system initiated by hydrolysis of the plasma membrane phospholipid sphingomyelin to generate ceramide. Ceramide acts as a second messenger in activating the apoptotic cascade. Diverse cytokine receptors and environmental stresses utilize ceramide to signal apoptosis. In several cell systems ceramide links to the stress-activated protein kinase (SAPK)/c-jun kinase (JNK) cascade to signal apoptosis. The engagement of the sphingomyelin pathway in signaling apoptosis is tightly regulated by anti-apoptotic control mechanisms, and the balance between pro- and anti-apoptotic systems determines the magnitude of the apoptotic response in vitro and in vivo. This review describes the known elements and molecular ordering of ceramide-mediated apoptosis and the anti-apoptotic mechanisms that regulate its expression. Understanding of pro- and anti-apoptotic signaling involved in ceramide-mediated apoptosis and the modes of their co ordinated function may yield opportunities for pharmacological interventions with potential for clinical applications. PMID- 9374037 TI - Apoptosis and carcinogenesis. AB - Many tumours are characterised by increased levels of apoptosis. This observation establishes significance for this process in tumour development, but it does little to elucidate the nature of this role, nor does it yield information relevant to the early stages of carcinogenesis. To gain a better understanding of the importance of apoptosis, it has been necessary to create a number of transgenic model systems wherein the apoptotic response has been modified. Using this strategy, a number of genetic lesions have been identified which affect both the apoptotic pathway and predisposition to malignancy. These lesions can operate either directly, by blocking the induction of apoptosis; or indirectly, by increasing the selective pressure for further genetic change. The consequent deregulation of growth control and increase in mutation burden represent two key steps in carcinogenesis, underlining the pivotal role played in tumour suppression by the normal induction of apoptosis. PMID- 9374038 TI - Programmed cell death during animal development. AB - The formation of the hand during embryogenesis, the peeling of sunburned skin and the tremor associated with Parkinson's disease all result from a common process: cell death. Cell death occurs throughout the life span of the organism and represents the ultimate differentiative decision made by cells. Insight into the process of cell death will not only contribute to our understanding of basic developmental issues, but will also facilitate the development of therapeutic interventions that could alter the course of disease. Since all cells have the genetic machinery required to commit suicide, the ability to initiate it in a lineage-specific, non-inflammatory manner would allow for the irradication of specific cancers. Alternatively, inhibition of cell death pathways could rescue valuable but condemned cells, such as HIV infected CD4+ T cells or dopaminergic neurons in Parkinson's disease. The goal of this chapter is to provide both an overview of the basic principles that govern the cellular and molecular mechanisms mediating cell death, as well as serve as a reference of known examples of PCD and the genes that mediate this process. PMID- 9374039 TI - Apoptosis and the immune system. AB - Apoptosis is a physiological process of cell death that occurs as part of normal development and in response to a variety of physiological and pathophysiological stimuli. The effector mechanisms which carry out the death program are well preserved across species and evolution. Apoptosis is important in the immune system, and plays significant roles in the control of the immune response, the deletion of immune cells recognising self-antigens, and cytotoxic killing. Some of the molecular regulators of these processes, such as CD95 and bcl-2 family proteins are the subjects of intense research. Malfunctioning of the immune system may lead to increased or decreased cell death. Conversely, dysregulation of apoptotic pathways themselves may lead to a spectrum of human disease, including autoimmune disease and immunodeficiency. PMID- 9374041 TI - Neuronal cell death: when, why and how. AB - Apoptosis is recognised increasingly as a prominent event in nervous system development and disease. This form of death appears to obey the same rules in neurones as in other cells, in that it is initiated by similar extracellular perturbations and distinguished by similar morphological and biochemical changes. When neurones die after survival factor withdrawal, gene transcription is important, with the transcription factor c-jun and the cytoplasmic signalling cascade that regulates it being particularly significant in at least some types of cells. However, death can be induced in a transcription-independent manner by agents such as staurosporine. Both types of death involve activation of members of the ICE family of proteases but, surprisingly, the particular protease involved seems to depend very much on the manner in which death is initiated. PMID- 9374040 TI - AIDS and the death receptors. AB - Activation-induced cell death (AICD) of T cells involves the CD95 receptor/ligand system. T cell activation through the T cell receptor results in expression of the CD95 ligand (CD95L) that acts on CD95+ cells by direct binding and in a paracrine or autocrine fashion. In AIDS, upregulation of CD95L in T cells is accelerated by two viral gene products, HIV-1 Tat and gp120. The CD95 signaling pathway is, therefore, likely to represent an important road to cell death of the CD4+ T cells in AIDS. Recently, the early events in the CD95 signaling pathway have been identified. A key role hereby plays a receptor-interacting member of the interleukin 1 beta-converting enzymes (ICE), FLICE, that could be a target for therapeutic intervention. In addition to CD95, the role of other members of the TNF receptor superfamily in AIDS is discussed. PMID- 9374042 TI - Apoptosis and cytotoxins. AB - Most xenobiotics ultimately become lethally cytotoxic, according to concentration. Toxins with completely disparate mechanisms of action induce apoptotic cell death. This suggests that the threshold for the onset of cell death can be determined by the relative expression levels of genes which promote or suppress apoptosis. The selectivity of a toxin may thus be determined not only by the selective imposition of perturbation or the amount of damage inflicted, but also by how readily that cell engages apoptosis. Measuring damage to cells, therefore, does not necessarily predict outcome. The threshold for apoptosis is determined not only by the static phenotype of the cell, which may confer a high or low survival potential, but also by its capability when stressed to modulate the expression of genes which control survival. The trophic environment of a cell can also influence the threshold for death. These findings have a profound impact on concepts defining toxin selectivity and on attempts to use mechanistic information to predict toxicity to organisms. PMID- 9374043 TI - Programmed cell death in the reproductive system. AB - The reproductive system presents some of the best examples of programmed cell death, which is to be expected considering the dramatic cycles of tissue growth and regression in females. Hormones from the pituitary gland, gonads and uterus are responsible for coordinating cycles in which the preservation of cell survival and inhibition of apoptosis are important. In the ovary, atresia regulates the size of the follicle cohort for ovulation and is an archetype of apoptosis as induced by hormone withdrawal. The fate of an antral follicle- growth or atresia--is determined by circulating levels of gonadotrophins, and follicle-stimulating hormone (FSH) in particular. At the end of a menstrual cycle or pregnancy or lactation, hormone withdrawal triggers cell death and tissue remodelling and initiates a fresh cycle. In the endometrium, breast and prostate gland, steroid hormones are the principal survival factors and castration triggers regression of responsive tissues, which is sometimes decisive in the fight against disease. But while the primary trigger of cell death varies between tissues, underlying cellular mechanisms are more conservative and cell death/survival genes, such as bcl-2, bax and others that are expressed in other tissues, play important roles in the reproductive system too. PMID- 9374044 TI - The importance of oxidative stress in apoptosis. AB - In vitro studies have shown that apoptosis can be triggered by many distinct and different stimuli including exposure to physical and chemical agents or by the removal of growth factors. Free radicals and oxidative stress have been implicated in apoptosis, although there is much uncertainty regarding their importance. This review aims to address much of the existing ambiguity. PMID- 9374045 TI - Granulocyte apoptosis and inflammatory disease. AB - We have described a novel pathway available for the clearance of extravasated granulocytes whereby the cells undergo apoptosis, a process which controls the functional longevity of granulocytes in situ and the rate of which is modulated by external and internal control mechanisms. It leads to shut-down of the secretory processes and recognition of the intact senescent cell by a novel macrophage recognition mechanism which fails to stimulate the release of pro inflammatory mediators. Thus, by contrast with a granulocyte fate involving necrosis, apoptosis is likely to represent an injury limiting tissue removal process for granulocytes which would tend to promote resolution processes. It is speculated that dysregulation of this process or an imbalance between it and necrotic pathways may be important in inflammatory disease pathogenesis. Whether or not this is the case, the apoptotic mechanisms available in neutrophil and eosinophil granulocytes provide opportunities for the selective induction of apoptosis in specific inflammatory cells in what may represent novel therapeutic approaches to inflammatory disease. PMID- 9374046 TI - Computerised prostate boundary estimation of ultrasound images using radial bas relief method. AB - A new method is presented for automatic prostate boundary detection in ultrasound images taken transurethrally or transrectally. This is one of the stages in the implementation of a robotic procedure for prostate surgery performed by a robot known as the robot for urology (UROBOT). Unlike most edge detection methods, which detect object edges by means of either a spatial filter (such as Sobel, Laplacian or something of that nature) or a texture descriptor (local signal-to noise ratio, joint probability density function etc.), this new approach employs a technique called radial bas-relief (RBR) to outline the prostate boundary area automatically. The results show that the RBR method works well in the detection of the prostate boundary in ultrasound images. It can also be useful for boundary detection problems in medical images where the object boundary is hard to detect using traditional edge detection algorithms, such as ultrasound of the uterus and kidney. PMID- 9374047 TI - Time-frequency analysis of the first heart sound: Part 3: Application to dogs with varying cardiac contractility and to patients with mitral mechanical prosthetic heart valves. AB - The cone-kernel distribution (CKD) is first applied to the analysis of the intracardiac and the thoracic first heart sound (S1) of dogs in various cardiac contractile states, and secondly to the S1 of patients with mitral mechanical prosthetic heart valves. The CKD of native S1 in dogs shows that the dominant components of S1 are generally concentrated in a band at around 50 Hz with a horizontal flat or a semi-lunar shape, independently of the myocardial contractile state. There is no significant systematic rising frequency component. The instantaneous frequency of S1 shows a good cross-correlation with the time derivative of the left ventricular pressure (dP/dt), but the maximum frequency is not proportional to the maximum of dP/dt. The CKD of S1 in patients with mitral mechanical prosthetic heart valves showed a pulse-like component with a high frequency bandwidth, which is distinct from the low constant-frequency components of S1 produced by native heart valves. PMID- 9374048 TI - Statistical analysis of signals from an intracavitary probe in a diseased heart. AB - A model study introduces the use of statistical signal processing to analyse the signals from an intracavitary probe. A complete derivation is given for the detection of one type of arrhythmogenic substrate, myocardial infarctions (MIs). Both the use of statistical signal processing and the detection of VT substrates, as opposed to activation maps, are unique. A quasi-stationary electromagnetic model with simplified geometry is presented. The model is used to simulate ventricular pacing in the presence of MI. The likelihood ratio is used for detection. A tabulation of the results from this model shows that an intracavitary probe can be used to detect MIs as small as 400 mm2 in 1 mV of noise with a detectability index of 0.495, where 0.5 indicates perfect detection. Sensitivity to noise can be reduced by analysing multiple heart beats. The results are only slightly affected by changing the probe from a cage frame design, which mechanically supports the electrodes on thin spokes, to a balloon design, which supports the electrodes on the surface of an insulating balloon. PMID- 9374049 TI - New approach to studies on ECG dynamics: extraction and analyses of QRS complex irregularity time series. AB - How to extract information intensively from ECGs for the diagnosis of cardiovascular diseases and assessment of heart function is a topical subject. Using a method based on the wavelet transform to calculate the irregularity of the QRS complex, which may relate to inotropy, the QRS complex irregularity time series is successfully extracted from original ECG signals. This provides a new approach to studies of ECG dynamics. With the help of non-linear dynamics theory, the QRS complex irregularity time series of eight subjects from the MIT/BIH arrhythmia database are studied qualitatively and quantitatively, and the characteristics of ECG dynamics are analysed extensively. The power spectrum, phase portrait, correlation dimension, largest Lyapunov exponent, time-dependent divergence exponent and complexity measure all verify the fact that ECG dynamics are dominated by an underlying 5-6-dimensional non-linear chaotic system, whose complexity measure is about 0.7. The QRS complex irregularity time series contains abundant information about all parts of the heart and the regulation of the autonomic nervous system, and so further analyses are of great potential theoretical and clinical significance to patho-physiology studies and ambulatory monitoring. PMID- 9374050 TI - Time-frequency analysis of heart murmurs. Part I: Parametric modelling and numerical simulations. AB - The object of this study is to compare the performance of two new bilinear time frequency representation techniques with the spectrogram to characterise the behaviour of heart murmurs produced by bioprosthetic heart valves implanted in the mitral or aortic position. The murmurs are those of mitral stenosis, mitral regurgitation, aortic stenosis, aortic regurgitation, a diastolic musical murmur and a systolic musical murmur. In the first part of the study, the general characteristics of the amplitude and the spectral content of these murmurs are determined by visual observation of the spectrogram of phonocardiograms obtained from several patients with known valvular pathology complemented with a literature review. A parametric model is then generated for each murmur signal. Stenotic and regurgitant murmurs are modelled as the sequential output of a bank of low-pass filters excited by a white noise input signal. The basic parameters of each filter are selected to simulate, as a function of time, the basic characteristics of random heart murmurs. Musical murmurs are modelled as a frequency-modulated deterministic sinusoid of constant amplitude. Numerical simulations of these random and musical heart murmurs are then generated and will be used in Part II to determine the best of three time-frequency representation techniques for analysing heart murmur signals. PMID- 9374051 TI - Time-frequency analysis of heart murmurs. Part II: Optimisation of time-frequency representations and performance evaluation. AB - The basic parameters of the spectrogram, the Choi-Williams, and the Bessel distributions are adjusted to provide the best time-frequency representations (TFRs) of the simulated murmur signals of mitral stenosis, mitral regurgitation, aortic stenosis, aortic regurgitation, and of two musical murmurs. The initial adjustment of the parameters of each TFR technique is performed by computing and minimising the relative averaged absolute error between the frequency contours at -3 dB and -10 dB of each TFR of the simulated murmurs and those of the theoretical distribution of the same signals. The results show that the spectrogram generally provides very good to excellent performance in representing the TFRs of stenotic and regurgitant murmurs. Improvements provided by the Choi Williams and the Bessel distributions are minor but not systematic for the two signal-to-noise ratios tested (0 and 30 dB) and for the two frequency contours estimated. The Bessel and the Choi-Williams distributions provide the best performance for the musical murmurs. The study shows that although a single technique cannot be optimal for all six murmurs, the spectrogram using a Hamming window of 30 ms is an acceptable compromise to detect the six simulated heart murmurs. PMID- 9374052 TI - Fast in vivo measurements of local tissue impedances using needle electrodes. AB - The objective of the research is to show an in vivo, fast method of measurement of local tissue bio-impedance in the beta dispersion region (0-200 kHz). A needle electrode is used for the purpose. The performances with respect to circuits, electrodes, measurement area and electrical representations are evaluated. A measurement example is shown, and the electrical representations are discussed and compared using it. The method discussed, although invasive, is considered to be useful for local tissue diagnoses concerning structures and physiological functions. PMID- 9374053 TI - Optimum electrode geometry for spinal cord stimulation: the narrow bipole and tripole. AB - A computer model is used to calculate the optimum geometry of an epidural electrode, consisting of a longitudinal contact array, for spinal cord stimulation in the management of chronic, intractable pain. 3D models of the spinal area are used for the computation of stimulation induced fields, and a cable model of myelinated nerve fibre is used for the calculation of the threshold stimulus to excite large dorsal column and dorsal root fibres. The criteria for the geometry of the longitudinal contact array are: a low threshold for the stimulation of dorsal column fibres compared with dorsal root fibres; and a low stimulation voltage (and current). For both percutaneous and laminectomy electrodes, the contact length should be approximately 1.5 mm, and the optimum contact separation, as determined by the computer model, is 2-2.5 mm. The contacts for a laminectomy electrode should be approximately 4 mm wide. This electrode geometry is applicable to all spinal levels where the dorsal columns can be stimulated (C1-2 down to L1). The stimulating electrode should preferably be used as a tripole with one (central) cathode. PMID- 9374054 TI - Self-learning fuzzy control of atracurium-induced neuromuscular block during surgery. AB - Self-learning fuzzy logic control has the important property of accommodating uncertain, non-linear and time-varying process characteristics. This intelligent control scheme starts with no fuzzy control rules and learns how to control each process presented to it in real time, without the need for detailed process modelling. A suitable medical application to investigate this control strategy is atracurium-induced neuromuscular block (NMB) of patients in the operating theatre. Here, the patient response exhibits high non-linearity, and individual patient dose requirements can vary five-fold during an operating procedure. A portable control system was developed to assess the clinical performance of a simplified self-learning fuzzy controller in this application. A Paragraph (Vital Signs) NMB device monitored T1, the height of the first twitch in a train-of-four nerve stimulation mode. Using a T1 setpoint = 10% of baseline in ten patients undergoing general surgery, a mean T1 error of 0.45% (SD = 0.44%) is found while a 0.13-0.70 mg k-1 h-1 range in the mean atracurium infusion rate is accommodated. The result compares favourably with more complex and computationally-intensive model-based control strategies for the infusion of atracurium. PMID- 9374055 TI - EEG-based system for rapid on-off switching without prior learning. AB - Details are reported of an EEG-based system that permits a person rapidly and reliably to switch on and off electrical devices without prior learning. The system detects and utilises increases in the amplitude of the alpha component of the EEG spectrum that occur when people close their eyes for more than 1 s. In addition to conventional signal-processing elements, the system incorporates a module for suppressing switching at the output of the system when predetermined noise threshold levels (such as those due to sources of EMG) are exceeded. This work indicates that a majority, perhaps in excess of 90%, of the adult population can demonstrate the control necessary to operate an electrical device or appliance using this system. It is indicated that multi-level switching and quasi continuous control options are feasible with further development of the system. This work has implications for the design of a system that could be used, for example, to assist the infirm or severely physically disabled to effect greater control over their environment. PMID- 9374056 TI - Compressed storage of arterial pressure waveforms by selection of significant points. AB - Continuous records of arterial blood pressure can be obtained non-invasively with Finapres, even for periods of 24 hours. Increasingly, storage of such records is done digitally, requiring large disc capacities. It is therefore necessary to find methods to store blood pressure waveforms in compressed form. The method of selection of significant points known from ECG data compression is adapted. Points are selected as significant wherever the first derivative of the pressure wave changes sign. As a second stage recursive partitioning is used to select additional points such that the difference between the selected points, linearly interpolated, and the original curve remains below a maximum. This method is tested on finger arterial pressure waveform epochs of 60 s duration taken from 32 patients with a wide range of blood pressures and heart rates. An average compression factor of 4.6 (SD 1.0) is obtained when accepting a maximum difference of 3 mmHg. The root mean squared error is 1 mmHg averaged over the group of patient waveforms. Clinically relevant parameters such as systolic, diastolic and mean pressure are reproduced with an offset error of less than 0.5 (0.3) mmHg and scatter less than 0.6 (0.1) mmHg. It is concluded that a substantial compression factor can be achieved with a simple and computationally fast algorithm and little deterioration in waveform quality and pressure level accuracy. PMID- 9374057 TI - Consequences of a small decrease of air temperature from thermal equilibrium on thermoregulation in sleeping neonates. AB - A new heating unit (servocontrolled skin temperature derivative system) has been designed to control the thermal environment in closed incubators. This type of control acts to attain and closely maintain a thermal equilibrium between a neonate's skin temperature and the environment. The present study aims to discover if thermal equilibrium is located within a thermoneutral range defined from oxygen consumption VO2 and body temperature, and whether it is more appropriate to define an optimal thermal environment. As regards VO2 and body temperature, results show that the air temperature reached at thermal equilibrium fulfils the definition of thermoneutrality. According to these criteria, a small decrease (1:5 degrees C) from thermal equilibrium also provides a near thermoneutral environment to the neonate but induces sleep disturbances and an increase in body movements. These two additional parameters delineate a narrower thermoneutral zone than does minimal metabolic rate because VO2 can stay constant even when air and body temperatures decrease. The results suggest that thermal equilibrium might be assimilated with a thermal comfort zone. PMID- 9374059 TI - Real time monitoring and analysis via the medical information bus, Part I. AB - Because of the complexity of monitored data in modern intensive care units (ICUs), and the risk of information being overlooked if medical staff have to pay attention to a multiplicity of monitoring apparatuses and alarm signals, the data for each patient may well be best presented on a single bedside screen after digestion by expert system techniques. Such central units should be able to deal with data from any monitoring apparatus, not just a predefined set. Furthermore, relay of the information from each bed to a central control station (one per ICU) is desirable for the purposes of permanent storage and for in-depth analysis. The paper describes a comprehensive system for ICU monitoring management and patient data analysis that integrates multiple expert systems and computers. The basic difficulties in applying expert system techniques to monitoring are overcome with the shell OPS/83, which allows calls to sequential C routines and allows time driven reasoning through appropriate design of the inference engine and rules. Flexibility as regards connectable monitoring apparatus is afforded by basing data acquisition mainly, though not exclusively, on the IEEE Medical Information Bus. PMID- 9374058 TI - Skin derivative control of thermal environment in a closed incubator. AB - Defining a thermoneutral environment remains difficult because thermoneutrality depends on both physical and physiological factors. A servocontrolled skin temperature derivative (SCS) heating device has been designed to control the thermal environment in closed incubators without the necessity of setting an air or skin reference temperature. The thermal environment obtained with the SCS program is controlled only by the neonate's skin temperature changes. For each neonate, the program allows the attainment of a specific individual thermal equilibrium (Teq). Although the mean value of the thermal equilibrium level measured on 29 neonates does not differ significantly from the neutral air temperature defined from the charts of other researchers, individual values of Teq differed greatly among neonates of similar birthweight and postnatal age. When compared with on/off heating programs, the SCS system permits greater quiet sleep occurrence and seems to provide an optimal thermal environment. The results suggest that the skin temperature derivative heating program takes into account both the ambient and physiological factors affecting body temperature regulation of each neonate. PMID- 9374060 TI - Real time monitoring and analysis via the medical information bus, Part II. AB - The complexity of the monitored data available in modern intensive care units suggests that they may be best processed, for presentation to medical staff, by expert system techniques. However, standard expert system shells are ill-fitted to either the basic sequential monitoring tasks of data acquisition and storage, or to handling the temporal considerations inherent in monitoring and in the recognition and processing of sporadic alarm signals. A solution to this dilemma is described: an expert system that has an appropriately designed inference engine and manages data acquisition via a medical information bus (MIB). Use of this MIB standard allows great flexibility as regards the monitoring apparatuses employed; in particular, the connection or disconnection of any apparatus is recognised and triggers the automatic reconfiguration of the network. PMID- 9374061 TI - Dynamometer for rat plantar flexor muscles in vivo. AB - A dynamometer is designed and fabricated to measure the force output during static and dynamic muscle actions of the plantar flexor muscles of anaesthetised rats in vivo. The design is based on a computer-controlled DC servomotor capable of angular velocities in excess of 17.5 rad s-1. The system controls the range of motion, angular velocity and electrical stimulation of the muscles, while monitoring the force output at the plantar surface of the foot. The force output is measured by a piezo-electric load cell that is rated at 5 kg capacity. Angular velocity and position are measured by a DC tachometer and potentiometer, respectively. All measurement devices are linear (r2 = 0.9998). The design minimises inertial loading during high-speed angular motions, with a variation in force output of less than 0.2%. The dynamometer proves to be an accurate and reliable system for quantifying static and dynamic forces of rat plantar flexor muscles in vivo. PMID- 9374062 TI - Monte Carlo simulation of a planar shoulder model. AB - Although variability of anthropometric measures within a population is a well established phenomenon, most biomechanical models are based on average parameter values. For example, optimisation models for predicting muscle forces from net joint reaction moments typically use average muscle moment arms. However, understanding the distribution of musculoskeletal morbidity within a population requires information about the variation of tissue loads within the population. This study investigated the use of Monte Carlo simulation techniques to predict the statistical distribution of deltoid and rotator cuff muscle forces during static arm elevation. Muscle moment arms were modelled either as independent random variables or jointly distributed random variables. Moment arm data was collected on 22 cadaver specimens. The results demonstrated the use of Monte Carlo techniques to describe the statistical distribution of muscle forces. Although assuming statistically independent moment arms did affect the statistical distribution shape, that assumption did not affect the median predicted forces. The standard deviations of muscle forces predicted using Monte Carlo techniques were similar to the standard deviation of muscle force predictions using the whole sample of specimens. It is concluded that Monte Carlo simulation techniques are a useful tool to analyse the interindividual variability of rotator cuff muscle forces. PMID- 9374064 TI - Power spectrum analysis of human femoral rotations during gait. AB - Femoral rotational waveforms sampled at 15 Hz for a duration 20 s satisfy the sampling rate and frequency resolution requirements of such waveforms during walking. Spectral analysis provides a unique signature of the frequency composition of such signals. This identity may prove useful in characterising human gait and could be of value in future studies of walking in health and disease. PMID- 9374065 TI - Use of an artificial neural network to analyse an ECG with QS complex in V1-2 leads. AB - A feed-forward neural network with back-propagation algorithm is used to distinguish anterior wall myocardial infarction (AI) and non-infarction based on analysis of computerised electrocardiograms. Data used in the study are from 132 patients diagnosed as having AI by automated electrocardiograph analysis. Their ECGs show an abnormal Q-wave (or QS complex) or small R progression in leads V1 and V2. However, 66 of them are diagnosed as old AI from the history, physical examination, echocardiogram and other laboratory data, whereas the other 66 are not. The network is trained with the data from half of the AI and non-infarction patients; respectively. The diagnostic accuracy rate is then tested with the remaining 66 patients (33 infarction, 33 non-infarction) who have not been exposed to the network. The neural network correctly identifies 90.2% of the patients with AI and 93.3% of the patients without infarction. The neural network is capable of diagnosing anterior wall myocardial infarction better than a computer electrocardiograph. PMID- 9374066 TI - A collective responsibility. PMID- 9374067 TI - Brewer's asthma due to malt contamination. AB - We describe a case of a 28 year old brewery worker who developed asthma whilst grinding malt. Lung function measurements demonstrated deterioration and improvement in lung function associated with work and absence from work. Inhalation challenge with ground malt from the brewery was positive but with ground malt from another source was negative suggesting a contaminant of the malt was responsible. Culture of the brewery malt showed heavy contamination with Aspergillus niger, but A. niger skin test was negative and aspergillus-specific IgG was not detected in the patients serum. Removal of the subject from the grinding room resulted in resolution of symptoms and normal lung function. We discuss the role of A. niger as an aetiological agent for occupational asthma with reference to the above case. PMID- 9374068 TI - Long-term sickness absence in an NHS teaching hospital. AB - This study was carried out to investigate the incidence and causes of long-term sickness absence in an NHS teaching hospital and to explore the role of the Occupational Health Service (OHS) in the management of long-term absence. Examination of attendance records of non-medical staff revealed an annual loss of 20,772 days due to spells of absence lasting 30 calendar days or more, (incidence 0.0528/WTE employees/year, prevalence 5.53 days long-term absence/WTE employee/year). A self-administered questionnaire was sent to 190 staff who had taken long-term absence during the previous 12 months. The response rate was 75%. Musculoskeletal problems and back pain in particular were the main reasons for absence, accounting for 30% of total days lost. Work-related illness made an important contribution with a third of those with musculoskeletal and a quarter of those with mental illness attributing the reason for their absence to work. Many staff reported non-medical factors such as delays in waiting for treatment and anxiety about return to work which prevented them from returning to work sooner. Only a minority of staff had attended OHS and referral was often delayed. OHS may have an important role to play in both prevention and management of long term absence by early assessment and intervention such as expediting treatment or arranging rehabilitation programmes. However in order to be effective, a clear policy to encourage early and consistent referral is required. PMID- 9374069 TI - Worker education in the primary prevention of occupational dermatoses. AB - This paper reports the evaluation of a skin care education programme conducted on a fine chemicals manufacturing site where over 1,000 employees are located. Approximately 60% are involved in chemical manufacture. Over a 12 month period production staff received training in prevention of occupational dermatoses linked to a site-wide poster initiative. The incidence of new cases of occupational dermatoses fell from 0.055 (70 cases in 1,277 employees) to 0.021 (27 cases in 1,277 employees) before and after the intervention respectively (p < 0.0001). After other factors such as chemicals handled, observer bias and changes in reporting related to socioeconomic climate were taken into account it is concluded that this study demonstrates the importance of worker education as a tool for primary prevention of disease. Training materials such as video and poster presentations may be effectively used in the chemical manufacturing industry as an adjunct to prevention and control of exposure to substances hazardous to the skin. Such methods may also be used in other industries where there are significant risks of dermatoses. PMID- 9374070 TI - Ventilatory function in brass workers of Gadaladeniya, Sri Lanka. AB - A cross sectional study was conducted to determine the respiratory hazards of brass workers. The study group was selected randomly. The control group was selected from the general population matched for age by cluster sampling. There was a total of 154 pairs for the final analysis. A questionnaire was administered to determine the prevalence of respiratory symptoms. Forced vital capacity (FVC), forced expiratory volume in the first second (FEV1.0), forced expiratory flow rate in the mid 50% of the FVC(FEF25%-75%) and peak expiratory flow rate(PEFR) were measured. Chest radiography was performed on those with 5 or more years of service. Cough, phlegm, chronic bronchitis and dyspnoea were significantly higher among brass workers. The ventilatory capacity was significantly lower in all the indicators except FVC. Smoking had no significant effect and a dose response relationship could not be demonstrated after inclusion of age in the regression model. Five point five per cent had evidence of septal lines while 6.4% had emphysema. PMID- 9374072 TI - The changing role of the occupational physician in the private sector: the Canadian experience. AB - The role of the occupational physician in the private sector is changing. Fewer large corporations maintain medical departments following the 'downsizing' trend of the late 1980's and early 1990's and those that do have extensively redefined the duties of the corporate medical director, often extending these duties to include responsibility for environmental health. Occupational medical services for employees previously covered by in-house services are now often provided by outsourcing. The private practice of occupational medicine has become the major growth area of the specialty in both the US and Canada. These trends have been driven primarily by economic imperatives and new management philosophies; the trend may have gone too far and a 'rightsizing' correction may be in progress. However, it is not clear that corporations in general are deriving the greatest value they can from their physicians or that the current generation of senior managers is utilizing its health professionals as effectively as they might. This is in part because the training, qualifications and capabilities of occupational physicians are not well understood. At least as important, however, is persistent confusion over desirable and appropriate roles that obscures the potential contribution of the medical professional within a management structure. We suggest that the greatest value in occupational medical services may be in the anticipation of risk related to health issues and the flexibility this gives the organization to manage the problem. PMID- 9374071 TI - Cohort mortality study of rubber and plastics product makers in Italy. AB - A retrospective cohort mortality study was carried out in 20 industrial factories in the Local Health Unit Bologna Sud (Emilia Romagna, Italy), where different rubber and plastics products were manufactured. The cohort consisted of 925 subjects (578 males and 347 females) employed for at least six months continuously; follow-up was between the beginning of operation of each factory, ranging between mid fifties and mid seventies, and 31 December 1989. For those exposed more than one year cause specific Standardized Mortality Ratios (SMRs) were computed using regional rates for comparison, 90% confidence intervals (CI) were calculated assuming the Poisson distribution. Among the 748 subjects employed for more than one year (457 males and 291 females) there were no lost to follow-up, 54 individuals were dead (41 males and 13 females) and for three subjects the cause of death was unknown. The results showed that all causes mortality was above expectancy in the total cohort (SMR = 123; 54 Obs; 90% CI = 97-154), among males (SMR = 117; 41 Obs; 90% CI = 89-152) and females (SMR = 143; 13 Obs; 90% CI = 85-228). Increased mortality for all malignant tumours was observed in the total cohort (SMR = 150; 25 Obs; 90% CI = 104-209) and for both genders. All nine lung cancer cases were observed among males, the SMR was equal to 218 and was statistically significant; seven cases occurred at duration of exposure less than 10 years and six at latency up to 20 years. The interpretation in terms of causality of the present investigation is limited by the small number of observations and by exposure definition solely in terms of employment in the study factories; nonetheless the results are indicating the existence, in this group of rubber and plastics product makers, of an adverse health effect which deserve further investigation. PMID- 9374073 TI - Occupational infection in an offal porter: a case of Q fever. AB - This case report describes the job activities of an offal porter who developed Q fever while processing livers from sheep. The diagnosis was confirmed by an increase in specific serial antibody titre. The main clinical features were anorexia, nausea, headache, pyrexia and elevated gamma-glutamyl transferase. Twenty-four cases of occupationally-acquired Q fever were noted by the Communicable Diseases Surveillance Centre (CDSC) between 1984 and 1994. This case report has an important feature in that a workplace visit was performed to evaluate the system of work and the circumstances of exposure to the infectious agent. Relevant preventive measures for this zoonotic infection are discussed. PMID- 9374074 TI - Need of harmonization of formative curricula for occupational physicians in Europe. PMID- 9374075 TI - Presentation and reporting of results. PMID- 9374076 TI - Poor control of exposure and ill health effects at solvent vapour degreasers. PMID- 9374077 TI - First line protracted venous infusion fluorouracil with CisDDP or carboplatine in advanced colorectal cancer. PMID- 9374078 TI - Arterial to end-tidal carbon dioxide gradient and physiological dead space monitoring during general anaesthesia: effects of patients' position. AB - METHODS: One hundred and five ASA I-II patients, scheduled for elective surgical procedures were studied in order to evaluate the effect of different surgical postures on physiological pulmonary dead space (VDphys/ VT) and arterial to end tidal carbon dioxide gradient [P(a-Et)CO2]. Patients were divided into four groups according to their position on the operating table: supine position (acting as control group, n = 33), 20 degree Trendelenburg position (n = 24), lateral position (n = 24) and prone position with convex saddle frame (n = 24). Physiologic dead space was measured using Enghoff modification of Bohr equation. Arterial CO2 partial pressure was measured by blood gas analysis and end tidal CO2 was measured by means of an infrared CO2 analyser. All measurements were performed 20 minutes after general anaesthesia induction, with patients mechanically ventilated by a constant inspiratory flow (TV = 8 ml kg-1, RR = 10 14, EIP = 10%) in order to reach a steady state end tidal CO2 ranging between 32 and 36 mmHg; afterwards surgery started. RESULTS: Arterial blood pressure showed a mean decrease of about 5-10% compared to baseline values, but no significant differences in arterial pressure decrease were found between the four groups. A significant VDphys/VT increase in postures other than supine was observed, unless it was statistically significant in lateral and prone position only; while P(a Et)CO2 was higher in all postures compared to supine. Changes of intrapulmonary gas and blood distribution due to patients' posture are probably responsible for the observed physiologic dead space and CO2 gradient differences. CONCLUSIONS: In conclusion, the clinical practice of predicting PaCO2 from EtCO2 must be tempered by recognition of the potential magnitude of P(a-Et)CO2 gradient, which is higher than normal during general anaesthesia and further increased when positioning the patient other than supine. PMID- 9374079 TI - Multiple organ failure due to Clostridium difficile sepsis. A case report. AB - A case of severe sepsis caused by Clostridium difficile infection in a 66-year old cirrhotic female is described. Severe systemic symptoms evolved rapidly to septic shock and ARDS, with signs and symptoms suggesting an acute abdomen requiring exploration for exclusion of surgical treatable diseases. The delayed diagnosis of Clostridium difficile infection probably contributed to the severity of the clinical course. PMID- 9374080 TI - Echocardiographic diagnosis of coronary sinus type atrial septal defect. A case report. AB - BACKGROUND: Coronary sinus type atrial defect is the result of an incomplete formation of the atriovenous fold. This is a rare anomaly that in a very few cases took advantage of echocardiographic diagnosis before surgery. We report on a case of coronary sinus type atrial septal defect diagnosed by means of transthoracic and transesophageal echocardiography. PATIENT: A 65 year old woman who was admitted to hospital for evaluation of dyspnea and pre-syncope. A diagnosis of secundum type atrial septal defect had been achieved few months before. METHOD DESCRIPTION: Color Doppler transthoracic echocardiography demonstrated evidence of left-to-right shunt through the coronary sinus-left atrium common wall, while transesophageal echocardiography showed a defect in the coronary sinus roof in its terminal portion, proximal to the atrial septum. At that level the shunt flow was demonstrated by the presence of a negative contrast after contrast injection. Both transthoracic and transesophageal contrast echocardiographies demonstrated the persistence of a left superior vena cava draining into the enlarged coronary sinus: the existence of a right-to-left shunt at the coronary sinus level suggested by transthoracic echocardiographic examination was not confirmed by transesophageal echocardiography. CONCLUSIONS: This is one of the few reported cases of coronary sinus type atrial defect diagnosed noninvasively and the diagnostic usefulness of both transthoracic and transesophageal echocardiographic approaches is stressed. PMID- 9374081 TI - A comparative light microscopic study of human midpalatal suture and periodontal ligament. AB - In order to provide information on the morphological features of both human midpalatal suture and periodontal ligament, bioptic samples were obtained from patients whose age was between 10 and 30 years. The samples were embedded in epoxy resin, sectioned, stained with toluidine blue and observed by light microscopy. The periodontal ligament and the midpalatal suture appeared very similar with regard to the histological characteristics of the connective tissue but differed in the nature of the bone tissue associated to it. The alveolar bone lining the periodontal ligament was a bundle bone whereas the bone lining the connective tissue of the sutures was both lamellar and bundle bone. The absence of osteoblasts, osteoclasts or undifferentiated cells in the sutures under examination suggests that they are subjected to a slow bone turnover during their life cycle. On the contrary, the presence of mesenchymal cells in the periodontal ligament supports the notion that these cells are precursors of osteogenic cells involved in the high rate of bone remodelling that characterizes the alveolar bundle bone. The present results are discussed taking into account physiologic and therapeutic aspects of the two structures under examination. PMID- 9374082 TI - Residential exposure to plasticizers and its possible role in the pathogenesis of asthma. AB - The plasticizer di(2-ethylhexyl) phthalate (DEHP) is widely used in building materials. DEHP is identified as the major plasticizer exposure in dwellings. We provide evidence that inhalation exposure to DEHP as aerosols adsorbed to particulate matter is as important, or more important, than vapor phase exposure. The particulate inhalation exposure to DEHP is considered to be significant due to its low clearance and extensive penetration into the pulmonary region. DEHP is capable of creating high local concentrations in the airways at the deposition site with subsequent local effects. The proposed mechanism of effect states that mono(2-ethylhexyl) phthalate (MEHP), the primary hydrolysis product of DEHP, mimics the inducing prostaglandins (PG) PGD(2), 9alpha,11betaPGF2, and PGF2alpha, and thromboxanes in the lungs, thereby increasing the risk of inducing inflammation in the airways, which is a characteristic of asthma. PMID- 9374083 TI - Chemotherapy of breast cancer: a historical perspective. AB - Over the last 30 years, our knowledge about the clinical behavior of breast cancer has increased substantially. Our ability to identify several prognostic subgroups and predict hormone-responsive and hormone-resistant disease has led to more rational utilization of endocrine and cytotoxic treatments. Breast cancer is sensitive to multiple cytotoxic compounds. It has been demonstrated that combination chemotherapy produces higher overall and complete remission rates than sequential single agents, and that doxorubicin-containing combinations are more effective than other regimens. The introduction of new cytotoxic agents, including the taxanes paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) and docetaxel, gemcitabine, anthrapyrazoles, thymidylate synthase inhibitors, antifols, and camptothecin analogues, has added substantially to our antitumor armamentarium. Combinations of new drugs with old agents have resulted in regimens of enhanced activity. A large number of randomized comparative trials will determine which combinations have the highest therapeutic ratio and need to be incorporated into the standard management of metastatic and high-risk primary breast cancer. PMID- 9374084 TI - A randomized study of paclitaxel versus cyclophosphamide/methotrexate/5 fluorouracil/prednisone in previously untreated patients with advanced breast cancer: preliminary results. Taxol Investigational Trials Group, Australia/New Zealand. AB - When administered as a single agent to previously treated patients with advanced breast cancer, paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has good activity. This trial was undertaken to compare paclitaxel with standard chemotherapy as front-line treatment for this disease. Patients with measurable or evaluable metastatic breast cancer, no prior chemotherapy for metastatic disease, and Eastern Cooperative Oncology Group performance status of 0 to 2 were randomized to receive either paclitaxel 200 mg/m2 intravenously over 3 hours for eight cycles over 24 weeks or standard treatment with oral cyclophosphamide 100 mg/m2/d days 1 to 14, intravenous methotrexate 40 mg/m2 days 1 and 8, intravenous 5-fluorouracil 600 mg/m2 days 1 and 8, and oral prednisone 40 mg/m2 daily days 1 to 14 (CMFP) for six cycles over 24 weeks. Patients whose disease progressed or relapsed were recommended for second-line therapy with epirubicin. Accrual has been completed with 209 patients randomized, and an interim analysis of the first 100 patients is reported here. Analysis of quality of life, assessed by the linear analogue scale and overall quality of life indices, is ongoing. Objective response occurred in 31% (confidence interval, 19% to 45%) with paclitaxel and 35% (confidence interval, 22% to 51%) with CMFP, with stable disease in an additional 33% and 29%, respectively. Median time to progression was 5.5 months with paclitaxel and 6.4 months with CMFP, with a median survival of 17.3 months for patients treated with paclitaxel and 11.3 months for those given CMFP. Grades 3 and 4 neutropenia occurred in 64% of patients with paclitaxel and 63% with CMFP. However, febrile neutropenia was the primary reason for hospitalization in 1% of paclitaxel courses, compared with 8% with CMFP. Major infections (World Health Organization grade 4) were seen in 7% of patients treated with CMFP, but in none of those given paclitaxel. Moderate or severe mucositis occurred in 13% of paclitaxel and 27% of CMFP patients. Alopecia and peripheral neuropathy were more common with paclitaxel. Quality of life assessments in the first 100 patients suggest better overall results for those treated with paclitaxel compared with CMFP. Preliminary analyses suggest that single-agent paclitaxel is well tolerated and provides control of metastatic cancer comparable to that of CMFP combination therapy when used as front-line therapy in an outpatient setting. PMID- 9374086 TI - Doxorubicin plus paclitaxel in advanced breast cancer. AB - The combination of bolus doxorubicin and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) as a 3-hour infusion is highly active in patients with metastatic breast cancer, but it has considerable cardiotoxicity. In this ongoing study, the potential effect of increasing the interval between administration of a short infusion of doxorubicin followed by a 3-hour infusion of paclitaxel was evaluated. Included were patients with metastatic breast cancer, who received doxorubicin 50 mg/m2 followed by paclitaxel 200 mg/m2 at intervals of 30 minutes, 4 hours, and 24 hours every 3 weeks. As of February 1997, 34 patients have been enrolled, two patients are too early to evaluate, and 13 are continuing treatment. The preliminary response rate is 69% (95% confidence interval, 50% to 84%), ranging from 60% to 80% within the three schedules. The main toxicities consisted of grade 3/4 neutropenia in 65% of all courses, with febrile neutropenia in 2%. Stomatitis and paresthesia were rare. To date, eight of 32 patients have developed abnormal left ventricular ejection fraction values and one patient has developed congestive heart failure. Our preliminary conclusions are that bolus doxorubicin followed by a 3-hour infusion of paclitaxel is highly active against metastatic breast cancer. The potential for cardiotoxicity with the regimen is reduced considerably if the maximum recommended cumulative dose of doxorubicin is reduced to 360 mg/m2 with a maximum single dose of 50 mg/m2. PMID- 9374085 TI - Pilot study of primary chemotherapy with doxorubicin plus paclitaxel in women with locally advanced or operable breast cancer. AB - A pilot study of primary chemotherapy with bolus doxorubicin plus paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) infused over 3 hours was performed in 38 women with locally advanced and 41 with stage II/III breast cancer. Patients received four cycles of primary chemotherapy followed by surgery and treatment with cyclophosphamide/methotrexate/5-fluorouracil for six cycles. Preliminary data are available on 73 patients. Doxorubicin plus paclitaxel was well tolerated. Primary toxicity consisted of grade 1 or 2 reversible peripheral neuropathy and grade 3 alopecia. After a median follow-up of 13 months, none of the patients have developed cardiac toxicity or any significant alteration of the left ventricular ejection fraction, which was measured before treatment, at each cycle of doxorubicin plus paclitaxel, and every 3 months thereafter. Major clinical response of the breast tumor was observed in 88% of patients. At pathologic examination of the surgical specimen, 40% were pT1, 15% had no macroscopic tumor residue, and 7% had complete disappearance of invasive neoplastic cells. After a median follow-up of 17 months for patients with locally advanced breast cancer, freedom from progression was 67%, disease-free survival was 71%, and overall survival was 74%. The same end points were 100% for patients with stage II/III disease, with a shorter median follow-up of 10 months. In conclusion, doxorubicin plus paclitaxel is safe, feasible, and effective, and can be used as primary or adjuvant chemotherapy to assess its actual therapeutic role in women with early breast cancer. PMID- 9374087 TI - Paclitaxel plus doxorubicin in breast cancer: an Italian experience. AB - Based on preclinical data, phase I/II clinical trials were performed at Istituto Oncologico Romagnolo (IOR) Operative Units (Medical Oncology Departments of Forli, Rimini, and Ravenna, Italy) to determine the efficacy and toxicity of sequential administration of doxorubicin followed by paclitaxel (Taxol; Bristol Myers Squibb Company, Princeton, NJ) in the treatment of patients with advanced breast cancer that either had been previously untreated or that had relapsed after adjuvant therapy. In the phase I trial, 19 patients received bolus doxorubicin (50 mg/m2) followed after a 16-hour interval by paclitaxel (given at dose levels ranging from 130 to 250 mg/m2) by 3-hour infusion every 3 weeks, for a maximum of eight cycles. Paclitaxel doses were escalated in 30-mg/m2 increments if the maximum tolerated dose had not been reached in the previous dose level. Analysis of the 128 cycles assessable for toxicity demonstrated neutropenia (<500/microL) in 26 courses (20.3%), with no significant clinical events. No relevant clinical cardiotoxicity was observed. The paclitaxel maximum tolerated dose was not reached at the 250-mg/m2 dose level (no grade 3 or 4 extramedullary toxicity). In the IOR phase II trial, 13 patients were treated with fixed doses of both drugs (doxorubicin 50 mg/m2 and paclitaxel 220 mg/m2). Grade 4 neutropenia occurred in 39 of the 95 cycles, but was complicated by fever in only eight cycles (8.4%); three cycles required granulocyte colony-stimulating factor support. Peripheral neurotoxicity was the most common extramedullary side effect noted. Overall clinical responses in the IOR trials included 10 complete responses (31.3%) and 15 partial responses (46.9%), with an objective response rate of 78.1%. Comparison of these results with those obtained from a phase I trial using the opposite drug sequence showed comparable overall response rates, but IOR's sequence was associated with a higher complete response rate, as well as less frequent and less severe nonhematologic toxicity. PMID- 9374088 TI - Paclitaxel plus doxorubicin in metastatic breast cancer: preliminary analysis of cardiotoxicity. AB - This ongoing phase II trial was designed to determine the antitumor activity and cardiotoxicity of a combination of doxorubicin (50 mg/m2) and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) (175 to 225 mg/m2 over 3 hours) as first-line chemotherapy for metastatic breast cancer. Of 76 patients entered so far, 57 who had received at least three courses of chemotherapy are assessable for efficacy and cardiac toxicity. A slight majority (57%) of the patients entered had prior adjuvant chemotherapy, including 33% with anthracycline containing combinations. An objective response was achieved by 70% of patients, with 18% complete responders. The main noncardiac toxicities were alopecia, neutropenia, mucositis, and peripheral neuropathy. Overall, after a median cumulative doxorubicin dose of 350 mg/m2, the evolution of left ventricular ejection fraction (LVEF) values did not significantly decrease from baseline to the sixth course of therapy. However, LVEF values decreased significantly in eight patients (14%). The LVEF decreased by more than 14% over basal values in three patients, although the final determination was still above the lower limits of normal. The remaining five patients had LVEF decreases that fell below the lower limits of normal (33% to 48%). None of the patients developed clinically evident heart failure. Our results indicate that the combination of doxorubicin (50 mg/m2) plus paclitaxel (175 to 225 mg/m2) is effective and does not induce a clinically relevant cardiotoxicity. PMID- 9374089 TI - Prospective randomized trial of paclitaxel alone versus 5 fluorouracil/doxorubicin/cyclophosphamide as induction therapy in patients with operable breast cancer. AB - The objective of this study was to compare the antitumor activity of single-agent paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) with that of the 5-fluorouracil/doxorubicin/cyclophosphamide (FAC) combination by evaluating the extent of residual disease in the breast and regional lymph nodes of patients with breast cancer following four cycles of induction chemotherapy. Patients with histologically confirmed invasive but noninflammatory carcinoma of the breast stages T2-3, N0-1, M0 were eligible to enter the study. Patients were treated with four cycles of either FAC or single-agent paclitaxel before local therapy. Following local therapy, treatment of the two arms was identical. Of 104 operable breast cancer patients who were treated with either regimen, 78 were evaluable for response to preoperative chemotherapy and had undergone local therapy. Age, TNM classification, and estrogen receptor status of the patients were similar in the two groups. Following induction chemotherapy, the extent of disease in the breast and the distribution and number of positive nodes were similar between the two treatment arms. Disease progressed in two patients in the FAC arm and in none in the paclitaxel arm during the induction phase of therapy. A higher fraction of patients had neutropenic fever during the paclitaxel treatment. Initial data from this ongoing randomized study show that paclitaxel alone has comparable anticancer activity with FAC in patients with early breast cancer. The degree of cytoreduction was similar with both induction therapies. PMID- 9374090 TI - Phase II study of paclitaxel and epirubicin as first-line therapy in patients with metastatic breast cancer. AB - Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), the first taxane used in routine clinical practice, has aroused considerable interest for its high single-agent activity against breast cancer and for its novel mechanism of action. Epirubicin, the 4' epimer of doxorubicin, is another agent with a high activity against breast cancer and is known for its lower rate of toxic side effects, especially toxic cardiac events, compared with its mother compound. The combination of paclitaxel and doxorubicin yielded response rates between 63% and 93% in phase I/II studies. In these studies, however, the investigators reported severe cardiac toxic events. The rationale for the current study was therefore to evaluate the combination of paclitaxel/epirubicin, focusing mainly on cardiac toxicity. In two groups, 85 patients with metastatic breast cancer entered the study. Approximately 20% of the patients had primary metastatic breast cancer with large tumors at the primary site. Half of the patients had received adjuvant chemotherapy. Study medication in group A consisted of epirubicin 60 mg/m2 given intravenously over 1 hour, followed by paclitaxel 175 mg/m2 administered as a 3 hour intravenous infusion after premedication with steroids, antihistamines, and H2-blockers. In group B, epirubicin 90 mg/m2 was combined with paclitaxel 175 mg/m2, given in the same manner as in group A. Dose escalation to 225 mg/m2 paclitaxel was planned in both groups. The main toxicity in both groups was neutropenia (73% World Health Organization grade 3/4 in group A and 93% in group B). Other hematologic side effects were rare. No febrile neutropenia was reported in group A, but two episodes occurred in group B. Peripheral neuropathy, arthralgia, and myalgia were mild (only World Health Organization grades 1 and 2). Alopecia was universal. In group A, the paclitaxel dose could be escalated to 200 mg/m2 in 15 patients and to 225 mg/m2 in seven patients. Dose reduction due to severe neutropenia was necessary in 11 patients. No cardiac events were reported in group A. In group B, the paclitaxel dose could be escalated to 200 mg/m2 in only one patient, and no patient reached 225 mg/m2. Three patients needed a dose reduction. In this group, one patient had a greater than 10% decrease in the left ventricular ejection fraction with no clinical signs. In group A, 43 patients were evaluable for response; in group B, 25 patients were evaluable. Thirteen patients were out of protocol with only bone metastasis, and two patients had more than one prior chemotherapy for metastatic disease. The response rate was identical in both groups, with five complete remissions and 24 partial remissions in group A and three complete responses and 14 partial remissions in group B. The duration of response was 8.2 months in both groups. The median cumulative epirubicin dose was 420 mg/m2 in group A and 630 mg/m2 in group B. The combination of paclitaxel 175 mg/m2 and epirubicin 60 or 90 mg/m2 can be administered safely to patients with metastatic breast cancer. Although response was not the primary end point of this trial, the response data are nonetheless encouraging and suggest that further evaluation of this combination line treatment of metastatic breast cancer is warranted. PMID- 9374091 TI - Weekly paclitaxel with epirubicin as second-line therapy of metastatic breast cancer: results of a clinical phase II study. AB - Phase I/II trials have shown that combination of an anthracycline with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) represents a high-potency therapy for treatment of patients with metastatic breast cancer, with response rates exceeding 90%. This phase II trial was conducted to test the tolerability and efficacy of weekly epirubicin plus paclitaxel as second-line therapy for patients with pretreated metastatic breast cancer. In this study, 35 patients with previous hormone therapy and/or chemotherapy were treated at a weekly dose of paclitaxel 80 mg/m2 with epirubicin 35 mg/m2 (10 patients, 123 cycles) or paclitaxel 80 mg/m2 with epirubicin 25 mg/m2 (25 patients, 218 cycles). The dose reduction of anthracyclines became necessary due to severe hemotoxicity (neutropenia World Health Organization grade 3 to 4 in 30.2% of cycles). The therapy schema included a 2-week therapy interval after each treatment period of 6 weeks, with treatment continued until response or disease progression. Overall, 18 patents (51.4%) presented with responses (complete response or partial response) to therapy, with seven (20%) achieving a complete response after six to 18 cycles. In three cases (8.6%), tumor state was unchanged for a median interval of 11 weeks (range, 5 to 20 weeks). Progressive disease was observed in seven cases (20%), and seven patients (20%) were not evaluable. Following epirubicin dose reduction, neutropenia World Health Organization grade 3 to 4 occurred in only 18.1% of cycles. Referring to nonhematologic toxicity, alopecia exceeded World Health Organization grade 2. Other nonhematologic toxicities exceeding grade 2 were observed in only a few courses and were not statistically relevant. No clinically relevant deterioration of cardiac function was observed at a median cumulative dose of epirubicin 285 mg/m2 (maximum cumulative dose, 630 mg/m2). This study has substantiated that the schedule used is highly efficient and well tolerated as second-line chemotherapy for patients with metastatic breast cancer. PMID- 9374092 TI - A phase II trial of epirubicin plus paclitaxel in metastatic breast cancer. United Kingdom Coordinating Committee for Cancer Research Breast Cancer Sub Committee. AB - Epirubicin and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) is an active combination for the treatment of metastatic breast cancer. A multicenter pilot phase II trial evaluated this combination in 35 patients treated with epirubicin 75 mg/m2 given as a 1-hour infusion, immediately followed by paclitaxel 200 mg/m2 given as a 3-hour infusion every 3 weeks. All patients had metastatic disease and had received a maximum of one chemotherapy regimen for advanced disease. A 43% response rate was observed in 30 evaluable patients, with two complete responses (7%) and 11 partial responses (37%). All patients were evaluable for toxicity. Hematologic toxicity was common and dose limiting. All patients underwent blood counts three times weekly. Grade 4 neutropenia was extremely common (91%), occurring at approximately days 10 to 12 and resolving rapidly in most cases. Thrombocytopenia was rare. Dose reductions were necessary in 10 patients, primarily for myelosuppression, but due to neuropathy in two patients. Alopecia was universal. Cardiac function was measured in all patients every two cycles. Among the first 24 evaluable patients, left ventricular ejection fraction decreased to below 40% in three patients, all of whom had received prior anthracyclines. Treatment was discontinued in one patient, who experienced no further deterioration. Under the auspices of the United Kingdom Coordinating Committee for Cancer Research, a randomized phase III study has been initiated in the United Kingdom to compare this combination of epirubicin/paclitaxel with combination epirubicin/cyclophosphamide. The primary end point of this study is progression-free survival, and the intention is to recruit 350 to 700 patients over the next 2 years. PMID- 9374093 TI - Phase I/II clinical trial of epirubicin and paclitaxel followed by granulocyte colony-stimulating factor in a 2-week schedule in patients with advanced or metastatic breast cancer. AB - Anthracyclines and taxanes are the most potent cytotoxic agents available for treating breast cancer. With combined therapy (either epirubicin or doxorubicin with paclitaxel [Taxol; Bristol-Myers Squibb Company, Princeton, NJ]), response rates of 70% to 90% have been reported. To achieve a maximal dose intensity per week, we decided to combine epirubicin 100 mg/m2 with escalating doses of paclitaxel, at successive dose levels of 135, 150, 165, and 180 mg/m2 in a 2-week schedule, with administration of subcutaneous granulocyte colony-stimulating factor 5 microg/kg from days 2 through 10. To date, 16 patients have been included, with six patients treated at level 1 (100/135 mg/m2 epirubicin/paclitaxel), four at level 2 (100/150 mg/m2), four at level 3 (100/165 mg/m2), and two at level 4 (100/180 mg/m2). The median age of all subjects is 55 years (range, 41 to 65 years). Five patients had received chemotherapy in the adjuvant setting. Of 79 treatment courses, 78 are evaluable for toxicity. The mean number of courses per patient is six (range, two to six courses). At dose level 1, one episode of febrile neutropenia with grade 4 thrombocytopenia occurred. No grade 4 extrahematologic adverse event has been noted so far. At dose level 2, we achieved a dose intensity per week of epirubicin 50 mg/m2 and paclitaxel 75 mg/m2, as expected. At dose level 3, the dose intensity per week was 47.5 mg/m2 and 78.8 mg/m2, respectively (expected 50 and 82.5 mg/m2). The current response rate, evaluated in 14 of 16 patients, is four complete remissions and eight partial remissions, for an overall response rate of 85%. Two patients had stable disease. Granulocyte colony-stimulating factor following epirubicin/paclitaxel on a 2-week schedule permits a very high dose intensity per week for both drugs and produces a high response rate in patients with advanced or metastatic breast cancer. PMID- 9374094 TI - Dose-finding study of paclitaxel and cyclophosphamide in women with advanced breast cancer. AB - The primary aim of this study was to define the maximum tolerated doses of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) given by 3-hour infusion and cyclophosphamide given by intravenous bolus every 3 weeks in patients with breast cancer. Patients had received a maximum of one prior chemotherapy for advanced disease. The maximum tolerated dose of the combination was also determined with granulocyte colony-stimulating factor (G-CSF) support. The 80 women who took part in this study received 347 fully evaluable courses of therapy. Starting doses were paclitaxel 135 mg/m2 and cyclophosphamide 750 mg/m2; G-CSF support (5 microg/kg subcutaneously) was added at the subsequent cycle if specific dose-limiting toxicities had occurred during the previous cycle. Febrile neutropenia and severe thrombocytopenia defined the maximum tolerated doses as paclitaxel 200 mg/m2 and cyclophosphamide 2,000 mg/m2, with or without G-CSF support, in patients with or without a prior chemotherapy. Recommended doses were paclitaxel 200 mg/m2 and cyclophosphamide 1,750 mg/m2 in these two groups of patients. The overall response rate was 25% among patients who had received prior therapy for metastatic disease and 50% in patients who had not been previously treated. Complete remissions were reported in 9% of patients, but only among those who were previously untreated. PMID- 9374095 TI - Infusional 5-fluorouracil/leucovorin plus paclitaxel and cisplatin in the first line treatment of metastatic breast cancer: results of a phase II study. AB - Our phase II study results demonstrating high efficacy and low toxicity for a weekly schedule of high-dose, 24-hour infusional 5-fluorouracil (5-FU)/leucovorin (LV) in intensively pretreated patients with metastatic breast cancer prompted the addition of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) to the regimen for a phase I/II study of outpatient second-line treatment of metastatic breast cancer. That study further prompted the addition of cisplatin to the regimen for first-line treatment. Twenty-eight patients with metastatic breast cancer have been evaluated. Pretreatment comprised adjuvant chemotherapy in 24 of 28 patients, but no prior chemotherapy for metastatic disease. Patients were treated with high-dose 5-FU 2 g/m2 (24-hour infusion) plus LV 500 mg/m2 (2 hour infusion before 5-FU) weekly for 6 weeks (days 1, 8, 15, 22, 29, and 36); in addition, paclitaxel 175 mg/m2 (3-hour infusion) was administered on days 0 and 21 and cisplatin 50 mg/m2 (1-hour infusion) on days 1 and 22 before high-dose 5 FU/LV, repeated every 50 days. Patients were treated as outpatients using Port-a Cath systems (SIMS Deltec Inc, St Paul, MN) and portable pumps. Neutropenia was common but mild to moderate and of short duration in most patients. No hospitalizations were required because of febrile neutropenia, and no granulocyte colony-stimulating factor support was used. Aside from common total alopecia, nonhematologic toxicities consisted mainly of moderate myalgia, diarrhea, mucositis, and nausea and vomiting. Hand-foot syndrome and peripheral neuropathy were cumulative and occurred most commonly during the third treatment cycle with mild to moderate expression. In 28 patients with bidimensionally measurable disease, 25% (seven of 28) attained a complete response, 57% (16 of 28) achieved a partial response, 11% (three of 28) had stable disease, and 7% (two of 28) had disease progression. Overall response was 82% (95% confidence interval, 66% to 100%). We conclude that the combination of paclitaxel/cisplatin with weekly high dose infusional 5-FU/LV appears to be effective in the first-line treatment of metastatic breast cancer. Preliminary results must be confirmed by the final analysis of response duration, time to progression, and survival. PMID- 9374096 TI - Paclitaxel with mitoxantrone with or without 5-fluorouracil and high-dose leucovorin in the treatment of metastatic breast cancer. AB - Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) is a highly active single agent in the treatment of breast cancer. However, its optimal incorporation into combination regimens awaits definition. We added paclitaxel, administered by 1-hour infusion, to a previously described combination regimen that included mitoxantrone, 5-fluorouracil, and high-dose leucovorin. Forty-six patients with metastatic breast cancer received the following regimen as first- or second-line treatment: paclitaxel 135 mg/m2 by 1-hour intravenous infusion on day 1; mitoxantrone 10 mg/m2 by intravenous bolus on day 1; 5-fluorouracil 350 mg/m2 by intravenous bolus on days 1, 2, and 3; and leucovorin 300 mg intravenous over 30 to 60 minutes, immediately preceding 5-fluorouracil on days 1, 2, and 3. Courses were administered at 3-week intervals for a total of eight courses in responding patients. Of 45 assessable patients, 23 (51%) had major responses. Previous chemotherapy, and in particular previous treatment with doxorubicin, did not affect response rate. The median response duration was 7.5 months. Myelosuppression was moderately severe, with 76% of courses resulting in grade 3 or 4 leukopenia. There were four treatment-related deaths, two sepsis, one congestive heart failure, and one sepsis and congestive heart failure, the last two after a large cumulative anthracycline dose. This combination regimen was active as first- or second-line therapy for metastatic breast cancer, although how its activity compares with that of other combination regimens or with paclitaxel alone is unclear. Myelosuppression was more severe than had been anticipated based on previous results with the mitoxantrone/5-fluorouracil/high dose leucovorin regimen or with single-agent paclitaxel administered at this dose and schedule. The infrequent development of cardiotoxicity in these patients suggests that the paclitaxel/mitoxantrone combination may not share the problems previously reported with paclitaxel/doxorubicin combinations. We have embarked on a phase I/II trial of paclitaxel/mitoxantrone and have determined the maximum tolerated dose to be 200 mg/m2 and 10 mg/m2, respectively, without the use of cytokines. Fifteen patients have been treated at the maximum tolerated dose, and it is too early to assess results. PMID- 9374097 TI - Prospective assessment of cardiac toxicity during a randomized phase II trial of doxorubicin and paclitaxel in metastatic breast cancer. AB - Since both doxorubicin and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) have substantial antitumor activity in advanced breast cancer, the combination of these two agents was a logical extension of the clinical development of paclitaxel. Early attempts used long infusions of both drugs, limiting the dose of both agents because of limiting gastrointestinal and myelosuppressive toxicity. Bolus doxorubicin combined with 3-hour infusion paclitaxel was reported to have dramatic antitumor activity, but clinically relevant cardiac toxicity in up to 20% of patients in two recent reports. In our current study the same schedules and doses of administration were used, limiting the total doxorubicin dose of 360 mg/m2. In-depth monitoring of cardiac function with noninvasive tests and endomyocardial biopsy were performed. Preliminary results suggest that, at these doses and schedule, the two-drug combination is safe, without unexpected toxicity. Limiting doxorubicin dose to 360 mg/m2 limits cardiac toxicity to levels expected from single-agent doxorubicin at similar cumulative doses. PMID- 9374098 TI - Dose-escalation study of weekly 1-hour paclitaxel administration in patients with refractory cancer. AB - To evaluate the safety and efficacy of weekly low-dose paclitaxel (Taxol; Bristol Myers Squibb Company, Princeton, NJ) in patients with refractory cancer, participating subjects received standard prophylactic medication followed by intravenous paclitaxel once a week for 3 weeks every 4 weeks. The 50-mg/m2 starting dose was increased by 10 mg/m2 for every five patients, as long as no dose-limiting toxicity had occurred in more than two of five patients treated at the preceding level. Eligibility criteria included metastatic and refractory malignant disease; an Eastern Cooperative Oncology Group performance status of 0, 1, or 2; and adequate hematologic, hepatic, and renal functions. Of 30 patients treated and evaluable for toxicity, 25 were evaluable for response. The majority of patients tolerated the treatment very well. In a total of 114 cycles, the worst toxicities observed were leukopenia (one grade 4, two grade 3), granulocytopenia (one grade 3, one grade 4), anemia (one grade 3, two grade 2), and infection (one grade 5, one grade 3). Three patients had grade 2 gastrointestinal toxicity and three had grade 1 peripheral neuropathy. Only one dose-limiting toxicity, at 100 mg/m2, has occurred. This patient died of bilateral pneumonia with neutropenia. We have observed partial responses in seven of 12 patients with breast cancer and three of eight with non-small cell lung cancer. The study remains open at the current dose level of 100 mg/m2/wk. Weekly low-dose paclitaxel is well tolerated and efficacious. Further phase II studies are warranted, to continue evaluation of this schedule of paclitaxel either alone or in combination with other drugs active in paclitaxel-responsive diseases. PMID- 9374099 TI - Dose-dense therapy with paclitaxel via weekly 1-hour infusion: preliminary experience in the treatment of metastatic breast cancer. AB - In an ongoing effort to establish the most appropriate dose and administration schedule for paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), the feasibility and safety of weekly 1-hour infusions were evaluated in 16 women with metastatic breast cancer previously treated with at least one chemotherapy regimen. Paclitaxel was administered on an outpatient basis at a starting dose of 100 mg/m2/wk for 4 consecutive weeks, with 4-week cycles continued until disease progression or the onset of intolerable toxicity. With 215 weekly infusions administered so far (median, 13 per patient), no episodes of febrile neutropenia have occurred, and no hematopoietic growth factors have been used. Plans for dose escalation were abandoned after grade 3 sensorimotor neuropathy developed in five of nine patients treated at paclitaxel 110 to 120 mg/m2. With dose escalation eliminated, further severe neurotoxicities were rare, but some degree of cumulative peripheral neuropathy was noted in all but three patients. No acute hypersensitivity reactions were noted. To date, six of 15 evaluable patients have achieved a major response to therapy, with one complete response and five partial responses. Four other patients had a minor response to therapy, one patient had an early death due to autopsy-proven extensive pulmonary microvascular carcinomatosis, and five patients have stable disease. Although the potential neurotoxicity of this regimen merits attention, the overall profile of a high therapeutic index, manageable toxicity, and convenient administration schedule makes this an attractive treatment alternative for patients with metastatic breast cancer. PMID- 9374100 TI - Phase I/II study of dose-intense doxorubicin/paclitaxel/cyclophosphamide with peripheral blood progenitor cells and cytokine support in patients with metastatic breast cancer. AB - Relapse following complete remission achieved with a single course of high-dose chemotherapy continues to be the main cause of treatment failure in patients with metastatic breast cancer. A phase I/II trial was initiated that combined the two most active drugs against breast cancer, doxorubicin and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), with cyclophosphamide, and delivered four cycles of these drugs with peripheral blood progenitor cells (PBPCs) and granulocyte colony-stimulating factor support in an outpatient setting. Patients with untreated metastatic breast cancer received two cycles of doxorubicin 60 mg/m2 and paclitaxel 200 mg/m2. During recovery from the second cycle, PBPCs were harvested. Responding patients were then admitted for a day to receive escalating-dose doxorubicin, paclitaxel, and cyclophosphamide followed by PBPC reinfusion on day 3 as outpatients. Seventeen patients have been enrolled to date. Ten patients completed treatment and received 34 cycles of high-dose chemotherapy every 21 days (range, 21 to 28 days). The median age was 47 years (range, 26 to 56 years) and the median number of metastatic sites was two (range, one to three). Five patients had received adjuvant chemotherapy (four cyclophosphamide/methotrexate/5-fluorouracil and one mitoxantrone-based). The most common toxic reactions were nausea and vomiting (75% of courses) and neurosensory (50% of courses). No patients had a decreased ejection fraction or overt congestive heart failure. Ten patients underwent cardiac biopsy (median doxorubicin, 253 mg/m2; range, 120 to 312 mg/m2); only one showed grade 1 cytotoxic changes with doxorubicin 240 mg/ m2. Six patients were admitted for neutropenic fever. Eight of 10 patients responded (two pathologically confirmed complete remissions in liver). At these doses, four cycles of doxorubicin, paclitaxel, and cyclophosphamide with PBPC and granulocyte colony-stimulating factor support every 21 days was well tolerated and showed evidence of activity. Enrollment at higher dose levels continues so that maximum tolerated dose can be defined. PMID- 9374101 TI - A phase II study of repetitive cycles of dose-intense carboplatin plus paclitaxel chemotherapy and peripheral blood stem cells in metastatic breast cancer. AB - To assess the feasibility of administering sequential cycles of dose-intensive therapy, 14 patients without prior chemotherapy for metastatic breast cancer were registered to be treated with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) at an initial dose of 250 mg/m2 over 24 hours (day 1), followed by carboplatin dosed to an area under the concentration-time curve of 16 (calculated according to the Calvert formula), every 3 weeks for four cycles. This combination was supported with peripheral blood stem cells collected following granulocyte colony-stimulating factor with or without cyclophosphamide and paclitaxel. One patient failed to peripheralize CD34 cells after cyclophosphamide/paclitaxel therapy and was taken off protocol. The remaining 13 patients entered the paclitaxel/carboplatin phase of the program, and nine completed all four cycles. The median duration of severe neutropenia (absolute neutrophil count < 100/microL) was 6 days, despite the absence of routine use of granulocyte colony-stimulating factor. Only five of a total of 42 chemotherapy cycles (12%) were associated with febrile neutropenia requiring hospitalization. Most patients did not require platelet transfusions. The most significant nonhematologic toxicity was gastrointestinal (grade 3 in three patients, two of whom had received local radiation for relapse before chemotherapy). Most patients developed grade 1 or 2 sensory neuropathy by the final cycle. Of the nine patients who entered the paclitaxel/carboplatin phase and were evaluable for response, five achieved a complete remission. This doublet of high-dose therapy can be given in an entirely ambulatory setting and is associated with modest hematologic toxicity. The value of this option in the treatment of metastatic breast cancer compared with more conventional approaches to high-dose therapy will require a greater number of patients evaluable for response and longer follow-up. PMID- 9374102 TI - Weekly high-dose paclitaxel in metastatic and locally advanced breast cancer: a preliminary report. AB - The optimal dose and schedule for paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) in the treatment of patients with advanced breast cancer are not known. Based on our phase I study in non-small cell lung cancer, in which the dose intensity of paclitaxel was successfully escalated by using a weekly schedule, we initiated a phase II study of weekly paclitaxel in previously untreated patients with metastatic breast cancer (MBC) and locally advanced breast cancer (LABC). Treatment consists of weekly paclitaxel 175 mg/m2 intravenously over 3 hours for 6 weeks, followed by a 2-week break. Doses are modified for neutropenia (absolute neutrophil count < 1,500/microL), bilirubin levels greater than 1.5 times normal, or greater than grade 1 neuropathy. Patients with MBC continue treatment until disease progression. Patients with LABC receive one to two cycles before proceeding to surgery if resectable. Thus far, 15 patients, eight with MBC and seven with LABC, are assessable for response and/or toxicity. Most patients have required dose modification, with median delivery of 75% (cycle 1) and 50% (cycle 2) of the planned dose of paclitaxel. Neutropenia has been the most common cause of dose reductions, although only one patient required treatment for neutropenic fever. Six patients have developed grade 2/3 peripheral sensory neuropathy, but with dose reductions many have continued treatment with stable or improving neurologic symptoms. Objective responses have been seen in 12 of 14 assessable patients, including six with MBC (one complete response, five partial responses) and six with LABC (two complete responses, four partial responses), for an overall response rate of 86% (95% confidence interval, 66% to 96%). All responding LABC patients have been rendered free from disease at surgery. These preliminary results are very encouraging. Accrual to the study continues. PMID- 9374103 TI - Future directions of paclitaxel-based therapy of breast cancer. AB - In the past 15 years, substantial progress has been made in the treatment of breast cancer, but management of women with breast cancer is still not curative in many patients. One important goal of new treatment strategies is that of defining criteria to specifically indicate therapies so that therapeutic benefit will no longer result from the indiscriminate application of treatment to all patients within a broad category of risk. This approach could be applied to paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ). The taxane is one of the most active new drugs developed for women with breast cancer. A number of conventional comparative trials are ongoing to assess its role in different stages of the disease. Some of its features, however, are suitable to explore more specific and relevant questions. Possibly because of paclitaxel's documented antiangiogenic properties, its high efficacy in combination could also provide an as yet unproven survival advantage in advanced breast cancer, with the drug being administered for adequately prolonged periods of time as a single agent after initial induction of response. In addition, available evidence suggests that patients with poor prognosis associated with overexpression of c-erb B2 (HER2) have a higher probability of responding to paclitaxel than patients with HER2 negative tumors. The clarification of this possibility is a priority. Should HER2 status be a predictor of response to paclitaxel and paclitaxel-based therapy, the use of the drug could be tailored to specific patient characteristics. The ability to discriminate between paclitaxel as a therapeutic option or a therapeutic indication is one of the challenges of the future development of this important drug. PMID- 9374104 TI - Ferritin expression after in vitro exposures of human alveolar macrophages to silica is iron-dependent. AB - The increased availability of catalytically active iron after silica exposure can present an oxidative injury to a living system. Sequestration of reactive iron would, therefore, confer a protective effect. The intracellular storage of iron by ferritin within macrophages can limit the potential for radical generation and cellular injury resulting from exposure to a metal chelate. We tested the hypothesis that in vitro exposure of human alveolar macrophages to silica increases the expression of ferritin through a posttranscriptional mechanism. Exposure of 1.0 x 10(6) macrophages to 100 microg/ml silica for 4 h increased light-subunit (L)-ferritin protein concentrations in both cell supernatants and lysates. Inclusion of 1.0 mM deferoxamine in the reaction mixtures inhibited increases in ferritin after silica. To test for a posttranscriptional regulation of ferritin protein expression, cells were incubated with acid-washed particles, silica with complexed zinc cation, and silica with complexed iron cation. L ferritin protein concentrations were increased in both cell supernatants and lysates after 4 h of exposure to silica with complexed iron cation. There were no increases in L-ferritin after incubations with acid-washed particles or silica with complexed zinc cation. There were no significant differences in levels of L ferritin cDNA between any of the exposures, suggesting a posttranscriptional control of ferritin expression. PMID- 9374105 TI - Interleukin-4 alters epithelial cell differentiation and surfactant homeostasis in the postnatal mouse lung. AB - Interleukin-4 (IL-4) is a pleotrophic cytokine which is increased during lung injury and inflammation. Epithelial cell morphology and surfactant homeostasis were assessed in 4-52-wk-old transgenic mice in which IL-4 was expressed in the bronchial and bronchiolar epithelial cells under the control of the Clara cell secretory protein promoter (CCSP-IL-4 mice). IL-4 caused progressive pulmonary infiltration with macrophages, lymphocytes, neutrophils, and eosinophils. Epithelial cell hypertrophy and mucus cell metaplasia were observed in the lungs of CCSP-IL-4 mice at all ages. Airway epithelial cells contained increased neutral glycoproteins and expressed gastric mucin, normally absent in the bronchiolar epithelium of the mouse. Immunohistochemical and biochemical studies demonstrated increased surfactant proteins A and B in lung sections and lung homogenates of CCSP-IL-4 transgenic mice. Increased immunostaining for surfactant proprotein C was also detected in type II epithelial cells of the transgenic mice. In contrast, surfactant protein B and CCSP expression was decreased or was absent in hypertrophic epithelial cells lining the conducting airways of transgenic mice. Lung-specific increase in T-cell proliferative responses to mitogenic stimulation and antibody secretion were detected in CCSP-IL-4 mice. Differentiated characteristics of respiratory epithelial cells were dramatically influenced by the chronic production of IL-4 in the conducting airways. Alterations in lung morphology in the CCSP-IL-4 mice are similar to some of those induced by antigenic stimulation or associated with chronic airway inflammation. PMID- 9374106 TI - Site- and cell-specific alteration of lung copper/zinc and manganese superoxide dismutases by chronic ozone exposure. AB - The antioxidant enzymes copper/zinc (Cu-Zn) and manganese (Mn) superoxide dismutase (SOD) have been implicated in protection of the lungs from oxidant damage. Mn SOD in particular may be related to acquired tolerance in cells following chronic ozone exposure. In order to study these protective and adaptive phenomena in oxidant injury, the cellular location and relative abundance of Mn SOD and Cu-Zn SOD were examined in the lungs of Fischer 344 rats following exposure to 0.0 and 1.0 ppm ozone for up to 3 mo using immunolabeling and morphometric techniques. Cu-Zn SOD labeling was found to be markedly reduced following ozone exposure in epithelial cells within airways and parenchyma. In contrast, a significant increase was noted in Mn SOD labeling in the centriacinar regions of exposed lungs for both alveolar macrophages and epithelial type II cells. Mn SOD labeling per epithelial type II cell was significantly increased in alveoli 0-400 microm beyond the bronchiole-alveolar duct junction (BADJ), while type II cell Mn SOD labeling was similar to control values with greater distance down the alveolar duct. No induction of Mn SOD was noted in type I epithelial cells, fibroblasts, or Clara cells. Thus, alterations in Cu-Zn and Mn SOD are both site and cell specific in the lungs. The differential increase in Mn SOD in type II cells of the proximal alveolar duct may reflect the ability of these cells to acquire tolerance and to resist further injury to repeated ozone exposure. PMID- 9374107 TI - Human airway epithelial cells stimulate T-lymphocyte lck and fyn tyrosine kinase. AB - Previous studies have shown that human airway epithelial cells (AEC) can stimulate allogeneic peripheral blood T-lymphocyte (PBT) proliferation. We now sought to determine which AEC surface molecule/T-cell coreceptors are involved in this process. AEC-induced PBT proliferation was inhibited by 25 microM genestein or herbamycin A (0.9 and 1.8 microM), both tyrosine kinase inhibitors. Anti phosphotyrosine immunoblots performed on PBT lysates after coculture with AEC demonstrated phosphorylation of 56kD and 60kD bands. To determine whether CD3 associated p59fyn, or CD4 and CD8 associated p56lck phosphotyrosine kinases (PTK) were involved, we assayed kinase activity in lymphocyte lysates immunoprecipitated with anti-p56lck and p59fyn mAbs. PBT cells or murine T-cell line transfectants expressing human CD4 (3G4) or human CD8alpha (3G8) were cocultured with AEC or A549, an alveolar-like cell line lacking class II Ag expression. After A549 or AEC coculture, p56lck activity in PB T-cells peaked at 2 min whereas p59fyn kinase activity continued to rise at 8 min. AEC (expressing class II Ags) stimulate PTK activity in both 3G8 and 3G4 cells. A549 stimulated p56lck in 3G8, but not in 3G4 cells. This activation of p56lck was not blocked by preincubation of A549 with anti-class I or anti-CD1d mAbs. An antibody generated in our laboratory, which recognizes an epithelial specific surface molecule (mAb L12) and which blocks AEC driven PBT proliferation, was shown to block PTK activity of peripheral blood T-cell lysates, though not of 3G8 lysates. These studies suggest that AEC are capable of stimulating CD4 and CD8 associated lck and CD3 associated fyn kinases through class II dependent and independent pathways. PMID- 9374108 TI - Phenotyping and cytokine regulation of the BEAS-2B human bronchial epithelial cell: demonstration of inducible expression of the adhesion molecules VCAM-1 and ICAM-1. AB - Airway epithelium may actively participate in inflammatory responses, such as occur in asthma. The presence and regulation of surface molecules on the airway epithelium, however, is incompletely understood. We have determined the phenotype of the human bronchial epithelial cell line BEAS-2B by flow cytometry. We confirmed previous observations that human bronchial epithelial cells constitutively express CD29, CD44, CD49a, CD49b, CD49c, CD49d, CD49e, CD49f, CD51, CD54 (ICAM-1), CD61, and HLA class 1. BEAS-2B cells were also found to constitutively express CD9, CD13, CD15, CD15s, CD23, CD33, CD36, CD40, CD41b, CD42b, CD48, CD50, CD71, and CD102 (ICAM-2). Culture of BEAS-2B cells with tumor necrosis factor (TNF)-alpha or interleukin (IL)-1beta (1 ng/ml) was found to enhance intercellular adhesion molecule-1 (ICAM-1) expression (several fold) and induce de novo CD106 [vascular cell adhesion molecule-1 (VCAM-1)] expression. TNF alpha or IL-1beta did not change the expression of CD9, CD13, CD16, CD23, CD29, CD31, CD32, CD35, CD45, CD61, or CD64 in BEAS-2B cells. IL-4 (1 ng/ml) also induced expression of VCAM-1 (1.5-fold) but not ICAM- expression while interferon gamma (1 ng/ml) enhanced only ICAM-1 expression (2-fold). Maximal VCAM-1 expression was obtained with the combination of TNF-alpha and IL-4 (8-fold). Using Northern blot hybridization analysis, ICAM-1 and VCAM-1 mRNA was detected in BEAS-2B cells stimulated with cytokines. VCAM-1 on stimulated BEAS-2B was functionally active as determined by adhesion of purified eosinophils and blockade with specific antibodies. Primary isolates of bronchial epithelial cells produced detectable levels of VCAM-1 protein and mRNA as detected by enzyme linked immunosorbent assay and reverse transcription-polymerase chain reaction, respectively. These results suggest that cytokine activation induces expression of ICAM-1 and VCAM-1 on airway epithelium, an event which may influence leukocyte infiltration and activation. PMID- 9374109 TI - Increased release of matrix metalloproteinase-9 in bronchoalveolar lavage fluid and by alveolar macrophages of asthmatics. AB - In order to determine whether matrix metalloproteinases (MMPs) contribute to inflammation in asthma, we have examined the release of MMPs in bronchoalveolar lavage (BAL) fluids and their production and regulation by alveolar macrophages (AM), in short-term culture. BAL was collected from 38 asthmatic subjects (24 untreated and 14 treated with inhaled corticosteroids), 26 healthy nonsmokers, and 18 patients with chronic bronchitis used as a control group for another inflammation. The profile of MMPs present in BAL fluid and AM supernatant, determined by zymographic analysis, was found to be similar in all populations. The main enzyme released was identified immunologically as MMP-9, a potent collagenolytic and elastolytic enzyme. Its release, measured using enzyme immunoassay, was significantly enhanced in fluids and in AM supernatants from untreated asthmatics compared with those from the other populations. Enhanced MMP 9 levels, in asthma, could not be explained by a different sensitivity of AM to interleukin-4, interferon-gamma, or dexamethasone, compounds that have been shown to inhibit MMP-9. The phorbol ester phorbol 12-myristate 13-acetate (PMA), a protein kinase C (PKC) activator, significantly increased MMP-9 in AM from healthy control subjects but not in those from untreated asthmatics. Calphostin C and H7, PKC inhibitors, significantly reduced PMA-stimulated MMP-9 release in AM from healthy control subjects and spontaneous MMP-9 release in AM from untreated asthmatics. H8, a PKA inhibitor, was inactive in both populations. These data suggest that the stimulation of MMP-9 release in AM from untreated asthmatic patients occurs, at least partly, via signals activating PKC. PMID- 9374110 TI - Developmental expression of mucin genes in the human respiratory tract. AB - Mucin glycoproteins play a key role in the normal function of the airway epithelium. We examined the expression of mucin genes, MUC3, 4, 5AC, 5B, 6, 7, and 8 in human fetal tissues to establish the localization and age of onset of expression of each mucin gene during human development. We detected expression of MUC4, 5AC, 5B, and 7 in the mid-trimester airway epithelium but did not detect expression of MUC3, 6, or 8. MUC4 was expressed in the trachea and large airways in the majority of cells in the airway epithelium. Expression of MUC5AC was only seen in individual goblet cells in the trachea, while MUC5B was expressed in the surface epithelium of the trachea at 13 wk but was largely restricted to submucosal glands by 23 wk of gestation. PMID- 9374111 TI - Transforming growth factor-beta1 is a potent inhibitor of glutathione synthesis in the lung epithelial cell line A549: transcriptional effect on the GSH rate limiting enzyme gamma-glutamylcysteine synthetase. AB - Glutathione (GSH) is an essential antioxidant tripeptide that protects mammalian cells against oxidants and xenobiotics. Patients with fibrotic lung disorders have very low levels of GSH in their alveolar epithelial lining fluid (ELF), whereas transforming growth factor (TGF)-beta is overexpressed in their alveolar epithelial cells. We observed that TGF-beta1 increased susceptibility of the human alveolar epithelial cell line A549 to H2O2-mediated cytotoxicity (P < 0.05), decreased the activities of the antioxidant enzymes glutathione reductase and catalase by 31%, and markedly decreased GSH content in A549 cells (P < 0.01). GSH depletion was associated with an equivalent decrease in the activity of the rate-limiting enzyme in GSH synthesis, gamma-glutamylcysteine synthetase (gamma GCS) (P < 0.01). Western blot analysis confirmed that the loss of gamma-GCS activity was associated with a marked decrease in gamma-GCS heavy subunit (gamma GCShs) protein. TGF-beta1 suppressed the steady-state level of messenger RNA (mRNA) for the gamma-GCShs gene, with a maximal effect at 24 h. The half-life of gamma-GCShs mRNA was not affected by TGF-beta1, but transcription of the gene was downregulated as determined with nuclear run-on assays. Our findings indicate for the first time that TGF-beta1 is a potent inhibitor of GSH synthesis in human lung epithelial cells, and that the inhibition is mediated, at least in part, by a transcriptional effect on the gene encoding gamma-GCShs. Regulation of gamma GCShs gene expression by TGF-beta1 is likely to play an important role in lower respiratory tract GSH homeostasis, and may represent a novel target for therapeutic efforts in lung fibrosis. PMID- 9374112 TI - Pyrrolidine dithiocarbamate attenuates endotoxin-induced acute lung injury. AB - Lung injury in the acute respiratory distress syndrome (ARDS) is in part due to polymorphonuclear leukocyte (PMN)-mediated oxidative tissue damage. By means of nuclear factor-kappaB (NF-kappaB) activation, oxidants may also induce several genes implicated in the inflammatory response. The dithiocarbamates are antioxidants with potent inhibitory effects on NF-kappaB. We postulated that the pyrrolidine derivative pyrrolidine dithiocarbamate (PDTC) would attenuate lung injury following intratracheal challenge with endotoxin (lipopolysaccharide; LPS) through its effect as an antioxidant and inhibitor of gene activation. Rats were given PDTC (1 mmole/kg) by intraperitoneal injection, followed by intratracheal administration of LPS. The transpulmonary flux of [125I] albumin (permeability index; PI) was used as a measure of lung injury. Northern blot analysis of total lung RNA was performed to assess induction of tumor necrosis factor-alpha (TNF alpha) and intercellular adhesion molecule-1 (ICAM-1) messenger RNA (mRNA) as markers of NF-kappaB activation. The effect of in vivo treatment with PDTC on LPS induced NF-kappaB DNA binding activity in macrophage nuclear extracts was evaluated with the electrophoretic mobility shift assay (EMSA). PDTC administration attenuated LPS-induced increases in lung permeability (PI = 0.16 +/- 0.02 for LPS versus 0.06 +/- 0.01 for LPS + PDTC; P < 0.05). TNF-alpha levels and PMN counts in bronchoalveolar lavage fluid (BALF) were unaffected, as were whole-lung TNF-alpha and ICAM-1 mRNA expression. PDTC had no effect on NF-kappaB activation as evaluated with EMSA. PDTC reduced lung lipid peroxidation as assessed by levels of malondialdehyde, without reducing neutrophil oxidant production. We conclude that PDTC attenuates LPS-induced acute lung injury. This effect occurs independently of any effect on NF-kappaB. PDTC reduces oxidant mediated cellular injury, as demonstrated by a reduction in the accumulation of malondialdehyde. Administration of PDTC may represent a novel approach to limiting neutrophil-mediated oxidant injury. PMID- 9374114 TI - Epithelial injury induced by exposure to residual oil fly-ash particles: role of reactive oxygen species? AB - Exposure of animals to airborne particulates is associated with pulmonary injury and inflammation. In the studies described here, primary cultures of rat tracheal epithelial (RTE) cells were exposed to suspensions of residual oil fly ash (ROFA). ROFA exposure resulted in progressive cytotoxicity whereby the amount of lactate dehydrogenase (LDH) released was significantly greater at 24 h than at 6 h after exposure. In a dose-dependent manner, exposure to 5, 10, or 20 microg/cm2 of ROFA for 24 h resulted in cytotoxicity and detachment of cells from the collagen matrix, along with altered permeability of the RTE cell layer. ROFA exposure caused cellular glutathione levels to decrease, producing a condition of oxidative stress in the RTE cells. Treatment of RTE cells with buthionine sulfoxamine, an inhibitor of gamma-glutamyl cysteine synthetase, was found to augment ROFA-induced cytotoxicity. Treatment with dimethylthiourea (DMTU) inhibited ROFA-induced LDH release and permeability changes in a dose-dependent manner. Treatment with the nitric oxide synthase inhibitor NG-monomethyl-D arginine (D-NMA) for 24 h was without effect. In rats intratracheally instilled with ROFA (500 microg/rat), intraperitoneal administration of DMTU (500 mg/kg) significantly ameliorated the degree of pulmonary neutrophilic inflammation present at 24 h. Overall, these in vitro findings suggest that ROFA-induced RTE cell injury may be mediated by hydroxyl-radical-like reactive oxygen species (i.e., species scavenged by DMTU) that are generated via non-nitric oxide pathways. The delay in induction of maximal RTE cell injury may reflect the time necessary to produce an oxidative burden by depleting antioxidant defenses such as cellular glutathione. PMID- 9374113 TI - Identification of early growth response gene-1 (Egr-1) as a phorbol myristate acetate-induced gene in lung cancer cells by differential mRNA display. AB - Cellular regulatory genes including transcription factors may play an important role in the induction, maintenance, and progression of lung cancer. These regulatory genes are inducible by various mitogenic stimuli including phorbol myristate acetate (PMA). The differential mRNA display method was used to identify potential early response genes regulated by PMA in non-small cell lung cancer (NSCLC) cell lines. Using this technique, several cDNA fragments were found to be potentially differentially regulated by PMA in the squamous NSCLC cell line NCI-H157. One of these cDNA fragments of approximately 100 bp was determined to be differentially induced by at least 30-fold by PMA by northern blot analysis and to hybridize to a single 3.4 kb mRNA species. This cDNA fragment was cloned, sequenced, and identified to be identical to a portion of the 3'-untranslated region of the human early growth response gene-1 (Egr-1). Using Egr-1 cDNA as a probe, it was demonstrated that PMA induces Egr-1 mRNA expression in at least three other NSCLC cells as well. In addition, PMA caused a transient increase in expression of the Egr-1 transcript reaching a maximum level by 1 h before decreasing in NCI-H157 and three other types of NSCLC cells. Treatment of these NSCLC cells with TGF-beta1 showed a transient increase in Egr 1 mRNA similar to PMA which also reached a maximum level after 1 h. Normal human bronchial epithelial (NHBE) cells also showed a rapid, transient increase in expression of Egr-1 mRNA after treatment with PMA. In contrast, treatment of NHBE cells with TGF-beta1 showed that expression of Egr-1 mRNA increased by 1 h but reached a maximum level only after 6 h. These results indicate that both PMA and TGF-beta1 can induce Egr- mRNA expression in NSCLC cells and NHBE cells; however, while PMA induces Egr-1 mRNA similarly in both cell types, TGF-beta1 induces Egr 1 mRNA expression more rapidly and more transiently in NSCLC cells than in NHBE cells. Our results suggest that Egr-1 may play different roles in response to mitogens in normal and malignant lung cells. PMID- 9374115 TI - The effect of treatment with budesonide or PGE2 in vitro on allergen-induced increases in canine bone marrow progenitors. AB - Increased bone marrow granulocyte-macrophage colony forming units (GM-CFU) in dogs developing allergen-induced airway hyperresponsiveness can be accounted for by a factor(s) present in serum following the allergen challenge. The present study evaluated whether in vitro treatment of bone marrow with budesonide or prostaglandin (PG)E2, prevents allergen-induced bone marrow stimulation. Eight dogs were studied after allergen and diluent inhalation challenges. Budesonide (10[-7] M) or PGE2 (10[-6] M) was added to bone marrow aspirated 24 h after challenge. Budesonide or PGE2 was also added to bone marrow aspirated before challenge, to which serum taken 24 h after challenge was subsequently added. Non adherent mononuclear bone marrow cells were incubated in the presence of the serum and granulocyte/macrophage colony stimulating factor (GM-CSF), granulocyte stimulating factor (G-CSF), or stem cell factor (SCF), and the number of GM-CFU counted. Allergen-induced increases in the number of GM-CFU in bone marrow aspirated 24 h after allergen (P < 0.001) were not attenuated by budesonide or PGE2 treatment (P > 0.05). However, GM-CFU increases in bone marrow aspirated before challenge and incubated with post-allergen challenge serum (P < 0.001) were blocked by either budesonide or PGE2 (P < 0.001). These findings demonstrate that budesonide and PGE2 can act directly on the bone marrow, preventing allergen induced increases in inflammatory cell progenitor production. This suggests that the bone marrow must be considered as a possible site of action for drugs which attenuate allergen-induced asthmatic responses. PMID- 9374116 TI - Airway eosinophils, T cells, Th2-type cytokine mRNA, and hyperreactivity in response to aerosol challenge of allergic mice with previously established pulmonary inflammation. AB - Asthma is characterized by acute episodes of nonspecific airway hyperreactivity and chronic pulmonary inflammation exacerbated by stimuli including allergen exposure. In order to reproduce the physiologic and immunologic responses that occur in asthmatic patients, we have characterized a model of antigen-induced inflammation in which allergic mice (B6D2F1) that had been challenged once with aerosolized ovalbumin and had developed a pulmonary cellular infiltrate were rechallenged 1 wk later. Pulmonary inflammation in rechallenged mice was substantially greater than that in single-challenged mice. Eosinophils and activated-memory T cells (CD44+, CD45RBlo) in bronchoalveolar lavage (BAL) fluid accumulated to higher levels and with faster kinetics in response to the second challenge than in response to the first challenge. Eosinophils in lung tissue also accumulated to higher levels but with similar kinetics in response to the second challenge than in response to the first challenge. Similarly, interleukin (IL)-4 and IL-5 steady-state mRNA levels in lung tissue increased after the second challenge and were higher than those measured after a single challenge. Furthermore, treatment of mice with an anti-IL-5 monoclonal antibody 2 h prior to rechallenge inhibited antigen induced eosinophil accumulation in the lungs. In mice challenged twice, peak in vivo bronchoconstrictor responsiveness to acetylcholine was increased following the second challenge compared with that observed following the initial challenge. In contrast, ex vivo tracheal smooth muscle contractile responsiveness to acetylcholine was not altered. Although mucus accumulation and epithelial damage in pulmonary tissue were evident in mice challenged twice, these parameters were slightly reduced compared with those seen at similar times in mice challenged once. Therefore, although these mice exhibit only slight bronchial epithelial damage, the presence of significant inflammation and airway hyperreactivity to acetylcholine as well as slightly increased baseline reactivity demonstrate important similarities with the pathophysiology of asthma. PMID- 9374117 TI - Intracellular degradation of newly synthesized apolipoprotein B. AB - Intracellular degradation of newly synthesized apolipoprotein (apo) B can occur at every stage of the secretory pathway, from the protein translation, polypeptide translocation across the membrane of endoplasmic reticulum (ER), to vesicular transport. The prevalence of apoB degradation at each stage varies in different hepatic cell systems examined. Proteolysis of nascent apoB can be catalyzed by the ubiquitin-proteasome system in the cytosol, and probably by unidentified ER resident proteases as well. Cytosolic and ER lumenal molecular chaperones that facilitate apoB translocation and folding may also assist in the degradation of misfolded apoB proteins. Factors affecting the synthesis and mobilization of lipids during lipoprotein assembly exert important regulatory effects on apoB degradation in trans, and specific hydrophobic amino acid sequence elements within the apoB-100 molecule may play roles in apoB degradation in cis. This review summarizes the current understanding of the cellular and molecular mechanisms responsible for intracellular degradation of apoB in hepatocytes. The emphasis centers primarily on the topology of apoB with respect to the ER membrane during and after apoB translation and its relationship to proteolytic mechanisms potentially involved in apoB degradation. PMID- 9374118 TI - Perinatal bile acid metabolism: analysis of urinary bile acids in pregnant women and newborns. AB - The metabolism of bile acids in 30 pregnant women was evaluated by analyzing the urinary composition of bile acids during late gestation (weeks 30-41) and again in these women and their newborn infants during the first week after delivery. The levels of individual bile acids were determined by gas chromatography-mass spectrometry after solvolysis and hydrolysis of bile acid conjugates. The mean total bile acid/creatinine ratio in pregnant women decreased from 1.22 micromol/mmol creatinine at 30-32 weeks of gestation to 0.15 micromol/mmol creatinine at 6-7 days after delivery. The mean percentage of 1beta-hydroxylated bile acids peaked at 27% at 3-4 days after delivery. In newborn infants, the mean total bile acid/creatinine ratio rapidly increased from 3.39 micromol/mmol creatinine at birth to 54.33 micromol/mmol creatinine at 7 days. During this period, large amounts (40-50%) of unsaturated ketonic bile acids, especially 7alpha,12alpha-dihydroxy-3-oxo-5beta-chol-1-en-24-oic acid and 7alpha,12alpha dihydroxy-3-oxo-4-cholen-24-oic acid, were observed in the infants' urine. These data suggest that, during the perinatal period, the formation of polyhydroxylated and unsaturated ketonic bile acids probably represents a mechanism for the excretion of bile salts, and that the metabolism of bile acids in both the mother and the infant changes significantly after birth. PMID- 9374119 TI - Site-specific regulation of gene expression by n-3 polyunsaturated fatty acids in rat white adipose tissues. AB - Dietary n-3 polyunsaturated fatty acids (n-3 PUFAs) limit abdominal fat depot hypertrophy. This could be due to regulation of the expression of proteins involved in adipose tissue metabolism. We investigated in vivo whether fatty acid synthase (FAS), hormone-sensitive lipase (HSL), lipoprotein lipase (LPL), phosphoenolpyruvate carboxykinase (PEPCK), CCAAT/enhancer binding protein alpha (C/EBP alpha), and leptin mRNA levels are affected in retroperitoneal (RP) and subcutaneous adipose tissues (SC) of rats fed n-3 PUFAs. For 4 weeks rats were fed high fat diets (20% fat) containing n-3 PUFAs given as eicosapentaenoic acid (EPA group), docosahexaenoic acid (DHA group), a mixture of these two fatty acids (MIX group), or native fish oil (FO group). A control group was fed with lard plus olive oil (LOO group). Final mean fat cell weight in RP ranged according to: LOO > or = EPA > or = DHA = FO = MIX. There was no difference in fat cell size of SC when comparing the LOO and MIX groups. The fatty acid compositions of RP and SC were similar and resemble that of dietary fat within each experimental group. In RP and compared to the LOO group, FAS, HSL, PEPCK, LPL, C/EBP alpha, and leptin mRNA levels decreased although not significantly in the EPA group, and were 40-75% lower in the DHA and MIX groups. mRNA levels were positively correlated to fat cell size in RP. In contrast, n-3 PUFAs had no effect on gene expression in SC. We conclude that n-3 PUFAs and mainly 22:6n-3 affect gene expression in a site-dependent manner in white adipose tissues via possible antiadipogenic effects. PMID- 9374121 TI - Inhibition of sex pheromone production in female lepidopteran moths by 2 halofatty acids. AB - Inhibition of sex pheromone production has been observed after topical treatment of pheromonal glands with DMSO solutions of 2-bromohexadecanoic acid, in three lepidopteran insects: Spodoptera littoralis, Thaumotopoea pityocampa, and Bombyx mori. It has been shown that this effect was brought about by action on the reductases and acetyltransferases of the final steps of the pheromones biosynthesis. Other halofatty acids, such as 2-fluoro- and 2-chlorohexadecanoic acids, were less active than the above bromoderivative whereas 2 bromotetradecanoic acid and 2-bromooctanoic acid exhibited activities quite comparable to the C-16 bromoacid. These results indicate that bromosubstitution is very important for this inhibitory action and chain length is of secondary importance. PMID- 9374120 TI - Analysis of a Chinese hamster ovary cell mutant with defective mobilization of cholesterol from the plasma membrane to the endoplasmic reticulum. AB - The factors involved in shuttling cholesterol among cellular membranes have not been defined. Using amphotericin B selection, we previously isolated Chinese hamster ovary cell mutants expressing defects in intracellular cholesterol transport. Complementation analysis among seven mutants identified one cell line, mutant 3-6, with a unique defect. The present analysis revealed three key features of mutant 3-6. First, the movement of cholesterol both from the endoplasmic reticulum and through lysosomes to the plasma membrane was normal. However, when intact 3-6 cells were treated with sphingomyelinase, movement of plasma membrane cholesterol to acyl CoA:cholesterol acyltransferase in the endoplasmic reticulum was defective. Cellular cholesterol was mobilized to this enzyme upon activation by 25-hydroxycholesterol. Second, mutant 3-6 did not utilize endogenously synthesized sterol or low density lipoprotein-derived cholesterol for growth as effectively as parental Chinese hamster ovary cells. Finally, despite normal movement of cholesterol to the plasma membrane, mutant 3 6 was amphotericin B resistant. The plasma membrane cholesterol content was normal as assessed by cholesterol oxidase treatment and Semliki Forest virus fusion, which suggests that the 3-6 mutation alters the organization of cholesterol in the plasma membrane. Our characterization of this mutant cell line should facilitate the identification of gene(s) required for this transport pathway. PMID- 9374122 TI - Effect of 360His mutation in apolipoprotein A-IV on plasma HDL-cholesterol response to dietary fat. AB - In order to determine whether genetic variability of apolipoprotein (apo) A-IV is responsible for the improvement in lipid profile when dietary saturated fats are replaced by carbohydrates or monounsaturated fats, 41 healthy male subjects were studied: 33 were homozygous for the 360Gln allele and 8 were heterozygote carriers of the 360His allele. These were administered three consecutive 4-week diets. The first was a diet rich in saturated fat (SAT diet, with 38% fat, 20% saturated. This was followed by a low fat diet (NCEP-I, with < 30% fat, < 10% saturated). The final diet was rich in monounsaturated fat (MUFA diet, with 38% fat, 22% monounsaturated). There was no difference in plasma lipid and apolipoprotein levels of both groups of individuals after consuming the SAT diet. Switching from this diet to the NCEP-I diet, carriers of the 360His allele presented a greater decrease in high density lipoprotein-cholesterol (HDL-C) (-10 vs. -1 mg/dL, P < 0.004) and apoA-I levels (-19 vs. -8 mg/dL, P < 0.037). Similarly, replacement of carbohydrates by monounsaturated fats produced a greater increase in HDL-C (9 vs. 1 mg/dL, P < 0.003) and apoA-I levels (9 vs. 2 mg/dL, P < 0.036) in carriers of the 360His mutation. Lecithin:cholesterol acyltransferase (LCAT) and cholesteryl ester transfer protein (CETP) activities and apoA-IV levels were also measured. However, no genotype-related differences were observed for these parameters. Our results suggest that variability in HDL-C and apoA-I response to diet is, at least partially, determined by the 360His mutation of apoA-IV. PMID- 9374123 TI - Interactions between cationic liposomes and an antigenic protein: the physical chemistry of the immunoadjuvant action. AB - The 18 kDa antigenic protein from Mycobacterium leprae (P) or its N-acyl derivative (AP) was incorporated in dioctadecyldimethylammonium bromide (DODAB) liposomes in water or in phosphate-buffered saline (PBS). In water, 100% P incorporation in liposomes contrasts with 65% in PBS. There is 75-80% AP incorporation to liposomes in water against 55-65% in PBS, showing that attachment of hydrophobic residues to the protein, instead of increasing, further decreases incorporation to the liposomes. From protein adsorption on latex, P affinity is larger than AP affinity for the latex surface whereas limiting adsorption for AP is much larger than that obtained for P, possibly due to AP aggregation in solution. P-induced rupture of liposomes containing [14C]sucrose was evaluated from dialysis of protein/liposomes mixtures. In water, P incorporation to the liposomes causes leakage of radioactive contents contrasting with the absence of leakage for P incorporation in PBS. Immunization tests for delayed type hypersensitivity indicate a enhancement of cell-mediated immunological response towards P/DODAB complexes that is not obtained for the isolated protein. Absence of leakage for P in PBS is associated with a P "lying over" on the liposome and optimization of protein presentation to the immunological system. PMID- 9374124 TI - Kinetics of the incorporation of dietary fatty acids into serum cholesteryl esters, erythrocyte membranes, and adipose tissue: an 18-month controlled study. AB - Tissue levels of n-3 fatty acids reflect dietary intake, but quantitative data about rate of incorporation and levels as a function of intake are scarce. We fed 58 men 0, 3, 6, or 9 g/d of fish oil for 12 months and monitored fatty acids in serum cholesteryl esters, erythrocytes, and subcutaneous fat during and after supplementation. Eicosapentaenoic acid (EPA) in cholesteryl esters plateaued after 4-8 weeks; the incorporation half-life was 4.8 days. Steady-state levels increased by 3.9 +/- 0.3 mass % points (+/- SE) for each extra gram of EPA eaten per day. Incorporation of docosahexaenoic acid (DHA) was erratic; plateau values were 1.1 +/- 0.1 mass % higher for every g/d ingested. Incorporation of EPA into erythrocyte membranes showed a half-life of 28 days; a steady state was reached after 180 days. Each g/d increased levels by 2.1 +/- 0.1 mass %. C22:5n-3 levels increased markedly. Changes in DHA were erratic and smaller. EPA levels in adipose tissue rose also; the change after 6 months was 67% of that after 12 months in gluteal and 75% in abdominal fat. After 12 months each gram per day caused an 0.11 +/- 0.01 mass % rise in gluteal fat for EPA, 0.53 +/- 0.07 for C22:5n-3, and 0.14 +/- 0.03 for DHA. Thus, different (n-3) fatty acids were incorporated with different efficiencies, possibly because of interconversions or different affinities of the enzymatic pathways involved. EPA levels in cholesteryl esters reflect intake over the past week or two, erythrocytes over the past month or two, and adipose tissue over a period of years. These findings may help in assessing the intake of (n-3) fatty acids in epidemiological studies. PMID- 9374125 TI - Effects of a high n-3 fatty acid diet on membrane lipid composition of heart and skeletal muscle in normal swine and in swine with the genetic mutation for malignant hyperthermia. AB - Knowledge concerning the genetic defects underlying malignant hyperthermia (MH) has expanded rapidly in recent years. In contrast, our understanding of the accompanying physiological changes is less clear. In this regard, the aim of this study was to determine whether normal swine and swine susceptible to MH (both heterozygous and homozygous animals) differ in their abilities to incorporate n-3 (omega 3) fatty acids into their skeletal and heart muscles. Swine of each genotype were fed either a diet rich in n-3 fatty acids (i.e., 5% fish oil) or an equal caloric diet low in n-3 fatty acids (i.e., 5% coconut oil). All dietary supplementations were given over a 13-week period. Subsequently, for each muscle type the following was determined: 1) the relative fatty acid profiles of eight different phospholipid classes and of neutral lipids, and 2) the total phospholipid and the total lipid content. The incorporation of n-3 fatty acids (i.e., eicosapentaenoic acid and docosahexaenoic acid) occurred within the various phospholipids and neutral lipids without influencing their total lipid content. The increased content of n-3 fatty acids in neutral lipids of skeletal muscle was related to a decreased content of medium-chain saturated fatty acids, whereas an increased incorporation of n-3 fatty acids into the membrane phospholipids was often related to a decreased content of linoleic acid and/or arachidonic acid. In general, the pattern of n-3 fatty acid incorporation was considerably different between the normal animals and the MH homozygous and heterozygous animals. The significant interaction between diet-induced n-3 fatty acid profiles and the stress-susceptible MH genotype may indicate an altered mechanism for fatty acid turnover and a repair mechanism to maintain cellular functions and structure. PMID- 9374126 TI - Novel mechanism of transcriptional activation of hepatic LDL receptor by oncostatin M. AB - In this paper we describe a sterol-independent regulation of low density, lipoprotein receptor (LDLR) transcription by the cytokine oncostatin M (OM) in HepG2 cells. We show that OM-induced expression is independent of cholesterol regulation and occurs at the transcriptional level. To elucidate regulatory mechanism(s), we constructed a luciferase reporter system comprising either the native LDLR promoter including repeats 1, 2, and 3, or a synthetic promoter vector containing repeats 2+3 only, allowing us to directly examine OM effects on individual elements. Specific mutants in repeats 1, 2, and 3 were made to facilitate the mapping of the OM effect on the promoter. Wildtype and mutant constructs were assayed for cholesterol and OM regulation. The results show that mutation within the core SRE-1 element of repeat 2 totally abolished cholesterol regulation but had no effect on OM inducibility. More interesting, a mutation within repeat 1 reduced basal transcription activity to 10% of the native promoter, but OM induction was unaltered. However, the identical mutation engineered in repeat 3 significantly decreased OM induction of LDLR promoter activity. These results suggest a novel regulatory role for the repeat 3 element in LDLR transcription. PMID- 9374128 TI - Phytanic acid alpha-oxidation: decarboxylation of 2-hydroxyphytanoyl-CoA to pristanic acid in human liver. AB - The degradation of the first intermediate in the alpha-oxidation of phytanic acid, 2-hydroxyphytanoyl-CoA, was investigated. Human liver homogenates were incubated with 2-hydroxyphytanoyl-CoA or 2-hydroxyphytanic acid, after which formation of 2-ketophytanic acid and pristanic acid were studied. 2 Hydroxyphytanic acid was converted into 2-ketophytanic acid and pristanic acid. When ATP, Mg2+, and coenzyme A were added to the incubation medium, higher amounts of pristanic acid were formed, whereas the formation of 2-ketophytanic acid strongly decreased. When 2-hydroxyphytanoyl-CoA was used as substrate, there was virtually no 2-ketophytanic acid formation. However, pristanic acid was formed in higher amounts than with 2-hydroxyphytanic acid as substrate. This reaction was stimulated by NAD+ and NADP+. Pristanic acid, and not pristanoyl-CoA was found to be the product of the reaction. These results suggest the existence of two pathways for decarboxylation of 2-hydroxyphytanic acid. The first one, starting from 2-hydroxyphytanic acid, involves the formation of 2-ketophytanic acid with only a small amount of pristanic acid being formed. The second pathway, which starts from 2-hydroxyphytanoyl-CoA, does not involve 2-ketophytanic acid and generates higher amounts of pristanic acid. The first pathway, which is peroxisomally localized, was found to be deficient in Zellweger syndrome, whereas the second pathway, localized in microsomes, was normally active. We conclude that the second pathway is predominant under in vivo conditions. PMID- 9374127 TI - Ca2+ channel blockers verapamil and nifedipine inhibit apoptosis induced by 25 hydroxycholesterol in human aortic smooth muscle cells. AB - We have characterized the death of human aortic smooth muscle cells induced by 25 hydroxycholesterol, an oxidation product of cholesterol. Chromatin condensation characteristic of apoptosis was observed by enzymatic (TUNEL) staining of chromatin, and by electron microscopy. Fourteen percent of cells treated with 5 microg/ml of 25-hydroxycholesterol for 24 h displayed chromatin degradation as determined by positive TUNEL staining. Addition of TNF alpha (10 ng/ml) and IFN gamma (20 ng/ml) increased the proportion of TUNEL positive cells to 30%, whereas the cytokines alone were without effect. After 48 h, 40% of the cells treated with 5 microg/ml of 25-hydroxycholesterol were TUNEL positive, and 21% of the cells displayed chromatin condensation. Oligonucleosomal DNA fragmentation typical of apoptosis was demonstrated by agarose gel electrophoresis. Furthermore, activation of the ICE-like protease caspase 3 (CPP32) was observed in cells treated with 25-hydroxycholesterol. Addition of the Ca2+ entry blockers verapamil or nifedipine to the culture medium inhibited apoptosis by more than 70% and reduced cytotoxicity, while removal of Ca2+ from culture medium reduced apoptosis by 42%. Within a few minutes after addition, 25-hydroxycholesterol induced intracellular Ca2+ oscillations with a frequency of approximately 0.3-0.4 min(-1). Thus it appears that Ca2+ influx through plasma membrane channels is an important signal in oxysterol-induced apoptosis. Addition of TNF alpha and IFN gamma enhanced cytotoxicity and resulted in a higher proportion of apoptotic cells, suggesting that inflammatory cytokines can increase the cytotoxicity of lipid oxidation products. PMID- 9374129 TI - Decreased production of low density lipoprotein by atorvastatin after apheresis in homozygous familial hypercholesterolemia. AB - Apheresis only partially controls raised low density lipoprotein cholesterol levels in patients with homozygous familial hypercholesterolemia, who usually respond poorly to lipid-lowering drugs. The efficacy and mechanism of action of a new 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, atorvastatin, was therefore investigated in seven homozygotes undergoing apheresis. One receptor negative and six receptor-defective homozygotes undergoing plasma exchange or LDL apheresis every 2 weeks were studied during 2 months each on placebo and on atorvastatin 80 mg daily. Changes in plasma lipids and mevalonic acid, an index of cholesterol synthesis, were measured and the kinetics of the rebound of low density lipoprotein cholesterol and apolipoprotein B after apheresis were analyzed. All subjects had significant improvements on atorvastatin. Mean decreases in low density lipoprotein cholesterol were 31% greater both pre- and post-apheresis on atorvastatin compared with placebo, accompanied by a 63% decrease in mevalonic acid. Percentage changes in low density lipoprotein cholesterol and mevalonic acid were closely correlated (r = 0.89, P = 0.007). The mean production rates of low density lipoprotein cholesterol and apolipoprotein B were 21% and 25% lower, respectively, on atorvastatin than on placebo (P < 0.005 and <0.02) but changes in mean fractional clearance rates were not statistically significant. We conclude that atorvastatin enhances the efficacy of plasma exchange and low density lipoprotein apheresis in patients who lack low density lipoprotein receptors. This effect appears to be due to marked inhibition of cholesterol synthesis which results in a decreased rate of production of low density lipoprotein. PMID- 9374130 TI - Relationship between lipoprotein lipase and high density lipoprotein cholesterol in mice: modulation by cholesteryl ester transfer protein and dietary status. AB - Plasma lipoprotein lipase (LPL) activity correlates with high density lipoprotein (HDL) cholesterol levels in humans. However, in several mouse models created either through transgenesis or targeted inactivation of LPL, no significant changes in HDL cholesterol values have been evident. One possible explanation for this species difference could be the absence of plasma cholesteryl ester transfer protein (CETP) activity in mice. To explore this possibility and further investigate interactions between LPL and CETP modulating HDL cholesterol levels in vivo, we examined the relationship between LPL activity and HDL levels in mice expressing the simian CETP transgene, compared with littermates not carrying the CETP gene. On a chow diet, increasing LPL activity was associated with a trend towards increased HDL levels (51 +/- 29 vs. 31 +/- 4 mg/dL highest vs. lowest tertiles of LPL activity, P = 0.07) in mice expressing CETP, while no such effects were seen in the absence of CETP (65 +/- 12 vs. 61 +/- 15 mg/ dL). Furthermore, in the presence of CETP, a significant positive correlation between LPL activity and HDL cholesterol was evident (r = 0.15, P = 0.006), while in the absence of CETP no such correlation was detected (r = 0.15, P = 0.36), highlighting the interactions between LPL and CETP in vivo. When mice were challenged with a high fat, high carbohydrate diet, strong correlations between LPL activity and HDL cholesterol were seen in both the presence (r = 0.45, P = 0.03) and absence (r = 0.73, P < 0.001) of CETP. Therefore, under altered metabolic contexts, such as those induced by dietary challenge, the relation between LPL activity and HDL cholesterol may also become evident. Here we have shown that both genetic and environmental factors may modulate the association between LPL activity and HDL cholesterol, and provide explanations for the absence of any changes in HDL values in mice either transgenic or with targeted disruption of the LPL gene. PMID- 9374131 TI - Effects of dimethyl sulfoxide on apolipoprotein A-I in the human hepatoma cell line, HepG2. AB - Exposure of HepG2 cells to 1% (v/v) dimethyl sulfoxide (DMSO), an effective free radical scavenger, for 24 h resulted in a 2-fold increase in the levels of apolipoprotein (apo) A-I mRNA and secreted protein, with no significant change in apoA-II, apoB, and apoE mRNA and protein levels. The induction of apoA-I was accompanied by a 50% increase in secreted HDL. Nuclear run-off assays indicated that the transcription rate of the apoA-I gene was also increased 2-fold in DMSO treated cells. Consistent with nuclear run-off assays, transient transfection experiments, using a series of pGL2-derived luciferase reporter constructs containing the human apoA-I proximal promoter, demonstrated that DMSO treatment increased apoA-I promoter activity 2-fold. We have identified a potential 'antioxidant response element' (ARE) in the apoA-I promoter that may be responsible for the increase in apoA-I transcriptional activity by DMSO. Gel mobility shift assays with an apoA-I-ARE revealed increased levels of a specific protein-DNA complex that formed with nuclear extracts from DMSO-treated cells. The formation of this complex is sequence specific as determined by DNA competition studies. When a copy of the ARE was inserted upstream of the SV40 promoter in a luciferase reporter plasmid, a significant 2-fold induction in luciferase activity was observed in HepG2 cells in the presence of DMSO. In contrast, a plasmid containing a mutated apoA-I-ARE did not confer responsiveness to DMSO treatment. Furthermore, pGL2 (apoA-I-250 mutant ARE), in which point mutations eliminated the ARE in the apoA-I promoter, showed no increase in luciferase activity in response to DMSO. These results implicate protein-DNA interactions at the antioxidant response element region in the transcriptional induction of human apoA-I gene expression by DMSO. PMID- 9374133 TI - Guinea pig apolipoprotein C-II: expression in E. coli, functional studies of recombinant wild-type and mutated variants, and distribution on plasma lipoproteins. AB - Guinea pig apolipoprotein C-II (apoC-II) lacks four amino acid residues in the amino-terminal, lipid-binding part compared to apoC-II from other mammalian species (Andersson et al. 1991. J. Biol. Chem. 266: 4074-4080). To explore whether this structural difference explains the low ability of guinea pig plasma to activate lipoprotein lipase in vitro, we have expressed guinea pig apoC-II in Escherichia coli and have constructed an insertion mutant with the four missing amino acid residues compared to human apoC-II. With a synthetic emulsion of long chain triacylglycerols, both the wild-type guinea pig apoC-II and the insertion mutant stimulated lipoprotein lipase similar to human apoC-II, but with chylomicrons from an apoC-II-deficient patient, 5- to 10-fold more of both wild type guinea pig apoC-II and the insertion mutant were needed. Studies of tryptophane fluorescence indicated a slight difference in how guinea pig apoC-II interacted with liposomes, and presumably with lipoproteins, as compared to human apoC-II. The level of apoC-II (11.5 +/- 5.4 microg/ml) was lower in guinea pig compared to human plasma, and most of guinea pig apoC-II was on HDL-like particles. These had decreased ability to donate apoC-II to lipid emulsions compared to human HDL. Some guinea pig apoC-II was associated with LDL which, as demonstrated by surface plasmon resonance, had higher affinity for lipoprotein lipase than human LDL, and inhibited rather than stimulated the lipase reaction in vitro. We conclude that while guinea pig apoC-II is fully competent to stimulate lipoprotein lipase, the sum of several different factors explains the low ability of guinea pig plasma to accomplish stimulation. PMID- 9374132 TI - Cellular uptake of lipoprotein[a] by mouse embryonic fibroblasts via the LDL receptor and the LDL receptor-related protein. AB - The sites and precise mechanisms of the catabolism of the atherogenic lipoprotein[a] (Lp[a]) are unknown. It has been proposed that the low density lipoprotein receptor (LDL-R) and the low density lipoprotein receptor-related protein (LRP) are involved in the catabolism of Lp[a]. To address the question whether and to what extent the LDL-R and/or LRP are involved in the catabolism of Lp[a], we studied the cellular uptake of Lp[a] via those two receptors using mouse embryonic fibroblast (MEF) cell lines lacking either the LDL-R, the LRP, or both receptors due to disruption of the respective mouse genes. 125I-labeled LDL and 125I-labeled Lp[a] uptake by wild-type fibroblasts (MEF1) was compared with that by fibroblasts homozygous for the disrupted LRP allele (MEF2), fibroblasts with two defective alleles for the LDL-R (MEF3), and fibroblasts homozygous for defects both in the LDL-R and LRP gene (MEF4). Compared with MEF1, 125I-labeled LDL uptake by MEF2 was 77%, by MEF3 30%, and by MEF4 24% of that by MEF1. However, no significant differences in the specific 125I-labeled Lp[a] uptake by the four mouse embryonic cell lines was observed. In comparison with MEF1, the 125I-labeled Lp[a] uptake by MEF2 was 98%, by MEF3 111%, and 73% by MEF4. Approximately 50% of the total cellular uptake of 125I-labeled Lp[a] was nonspecific. In conclusion, our results suggest that Lp[a] is a poor ligand for the LDL receptor and the LRP. The data of the displacement studies, however, indicated that the nonspecific uptake of Lp[a] constitutes a major route for the cellular Lp[a] catabolism in this study. PMID- 9374135 TI - Interaction of class A amphipathic helical peptides with phospholipid unilamellar vesicles. AB - The exchangeable apolipoproteins are important in determining the structure/function properties of lipoproteins. These proteins typically contain varying amounts of amphipathic helices. Five model peptides, 18A, Ac-18A-NH2, Ac 18R-NH2, 37pA, and 37aA, have been designed to investigate variations of the amphipathic alpha-helix structural motif on their lipid-binding properties. These include the 18-residue peptides, 18A and Ac-18A-NH2, examples of class A helices, and Ac-18R-NH2, which has the positions of acidic and basic residues interchanged relative to 18A. Three larger peptides were also studied: 36A, a dimer of 18A, 37pA and 37aA, dimers of 18A coupled by Pro (18A-Pro-18A) and Ala (18A-Ala-18A), respectively. We report here the results of a thermodynamic characterization of the binding properties of these peptides to small unilamellar vesicles of POPC. Partition coefficients, Kp, were determined by fluorescence spectroscopy and binding enthalpies, deltaH, by titration calorimetry. These parameters were used to obtain the free energies, deltaG0, and entropies, deltaS0, of binding. The results of this study indicate Kp values on the order of 10(5), with interactions being enthalpically but not entropically favored in all cases. The presence of positively charged residues at the interface (18A and Ac-18A-NH2) enhances binding but has little effect on the extent of bilayer penetration. The presence of tandem repeats decreases lipid affinities for these small, highly curved bilayers. Our results are consistent with the idea that interaction appears to be confined largely to the surface, with some degree of penetration of the hydrophobic face of the helix into the interior of the bilayer. PMID- 9374134 TI - Uncoupling protein gene: quantification of expression levels in adipose tissues of obese and non-obese humans. AB - The mitochondrial uncoupling protein (UCP), which is exclusively expressed in brown adipose tissue, regulates energy expenditure in rodents but its importance in the energy homeostasis of adult humans is uncertain. To study associations of UCP gene expression with human obesity, we determined, by a competitive reverse transcription-polymerase chain reaction assay, UCP mRNA expression levels in intra- and extraperitoneal adipose tissues of 79 obese subjects and 17 lean controls. UCP mRNA and internal standard RNA were reverse transcribed and coamplified in one reaction in which the same primers were used. The signal intensities of UCP mRNA products were compared with the signal intensities of standard RNA products to quantify UCP mRNA abundance. UCP mRNA was detected in all intra- and extraperitoneal adipose tissues studied. In both obese and non obese subjects, UCP mRNA abundance was higher in the intraperitoneal than in the extraperitoneal tissue (P < 0.001). Compared to lean controls, morbidly obese subjects showed a significantly lower age- and gender-adjusted UCP mRNA expression level in the intraperitoneal adipose tissue (3.467 +/- 2.483 vs. 6.917 +/- 4.292 amol/fmol beta-actin mRNA; mean +/- SD, P < 0.002), while UCP mRNA abundance in extraperitoneal adipose tissue did not differ between obese and nonobese subjects. These data are consistent with reduced energy expenditure in obesity, but it remains to be determined whether the association of decreased intraperitoneal UCP mRNA expression with obesity status reflects a causal contribution of brown adipose tissue function to the pathogenesis of obesity. PMID- 9374136 TI - Effect of vesicle size on their interaction with class A amphipathic helical peptides. AB - Throughout the life span of a lipoprotein particle, the type and number of exchangeable apolipoproteins on its surface varies with particle size, suggesting a role of surface curvature on the lipid-binding properties of these proteins. Peptides 18A, Ac-18A-NH2, Ac-18R-NH2, 37pA, and 37aA have been designed to investigate the lipid-binding properties of the amphipathic alpha-helix structural motif that appears to modulate the lipid-binding properties of the exchangeable plasma apolipoproteins. We report here the results of a quantitative thermodynamic characterization of the effects of modifying helix length and of varying both the location of charged residues about the polar face of the peptides and vesicle size on the lipid affinity and depth of bilayer penetration for model amphipathic alpha-helices. Partition coefficients, Kp, were determined by fluorescence spectroscopy, and binding enthalpies, deltaH, by titration calorimetry. The results indicate that Kp values are on the order of 10(5), with similar deltaG(o) values for the interactions of the peptides with vesicles of various sizes. It appears that a class A motif and increased alpha-helical content optimize binding for 18-residue peptides. The interactions of the model peptides with 20 nm SUV are enthalpically driven with small, negative entropy changes; however, interactions for larger vesicles are entropically driven, likely due to disordering of bilayer hydrocarbon chains. Thermodynamic data indicate that 37pA and 37aA induce greater disordering of bilayer hydrocarbon chains than Ac-18A-NH2. The results of this study suggest that the type of interaction, i.e., enthalpically or entropically driven, may be modulated by the lateral compressibility of the bilayer membrane. PMID- 9374137 TI - Linoleic acid potentiates TNF-mediated oxidative stress, disruption of calcium homeostasis, and apoptosis of cultured vascular endothelial cells. AB - Diet-derived lipids may influence cytokine-mediated endothelial cell dysfunction, including TNF-induced apoptosis. To test this hypothesis, oxidative stress, intracellular calcium levels, endothelial barrier function, cell viability, and apoptosis were measured in vascular endothelial cells treated with 90 microM linoleic acid (18:2, n-6) and/or 20 ng/mL TNF (100 U/mL). For short-term exposure, endothelial cells were exposed to 18:2 for 6 h or to TNF for 1.5 h. For long-term exposure, endothelial cultures were treated with 18:2 for 24 h and with TNF for 19.5 h. In cells exposed to 18:2 + TNF, pretreatment with 18:2 began 4.5 h before additional exposure to TNF for either 1.5 h (short-term exposure) or 19.5 h (long-term exposure). After treatment, endothelial cultures were washed and incubated with maintenance medium for up to 4 days. Although initial treatment with TNF or 18:2 significantly increased oxidative stress and intracellular calcium levels, only exposure to TNF induced apoptosis in cultured endothelial cells. Furthermore, the combined exposure to 18:2 + TNF potentiated TNF-induced apoptosis. Additional treatments with BAPTA-AM, n-propyl gallate, vitamin E, and with aurintricarboxylic acid partially protected against TNF- or 18:2 + TNF-induced apoptosis. The present study suggests that changes in the cellular lipid environment may markedly influence local TNF-induced events in the vascular endothelium, including endothelial cell apoptosis. Such mechanisms may play a role in the damage and death of vascular endothelial cells in atherosclerosis. PMID- 9374138 TI - Reduction mammaplasty in patients with bulimia nervosa. AB - Women with eating disorders have been disqualified as candidates for plastic surgery. We present a group of 6 young women with bulimia nervosa who presented with clinically symptomatic evidence of macromastia. All patients reported that dysfunctional eating habits, at least in part, where due to breast enlargement. Five patients underwent bilateral reduction mammaplasty. Patients were interviewed postoperatively and reported relief of physical symptoms and improvement in psychological well-being. Symptoms of eating disorders were completely eliminated or greatly reduced. This series has supported the contention that macromastia can produce a distortion of body image and become a secondary cause of eating disorders. Surgical correction of large breasts has improved body image, leads to the amelioration of associated eating disorders, and may in part represent a surgical treatment for a psychological abnormality. The presence of an eating disorder should not, therefore, automatically exclude a patient from surgical consideration. Routine preoperative evaluation of young women seeking plastic surgery should include a set of standard questions regarding eating behaviors. PMID- 9374139 TI - Local injection into mimetic muscles of botulinum toxin A for the treatment of facial lines. AB - The purpose of this clinical investigation is to confirm the efficacy of eliminating facial wrinkles by injecting botulinum toxin A into mimetic muscles. Fifty-four patients were injected with BOTOX A-14 in the corrugator superciliaris, 19 in the frontalis muscles, and 13 in the orbicularis oculis. Dilution was obtained by adding 4 ml preservative-free saline to 100 IU of BOTOX A. The dose used varied according to the patient. The severity of wrinkles and the intensity of muscle contraction (facial expression) were taken into account. The paralysis obtained in the mimetic muscles was effective for 6 months in 39 patients, 8 months in 10 patients, and 9 months in 1 patient. The results were documented by photographs, videotape, and electromyographies pre- and postinjection. To preserve the results, 21 patients (39%) demanded a second infiltration to achieve satisfactory results. Neither local nor general adverse effects were noted, except transitory eyebrow palsy in 2 patients, and edema and ecchymosis in 4 patients. The improvement obtained in facial mimetic wrinkles was satisfactory to the patient and to us. PMID- 9374140 TI - Single-stage, multimodality treatment of soft-tissue sarcoma of the extremity. AB - The present study describes the techniques available for single-stage sarcoma resection, soft-tissue reconstruction, and radiotherapy for limb preservation in patients who are unable to undergo primary wound closure after a complete soft tissue resection of their primary sarcoma. From 1989 to 1994, 19 patients (age range, 18-79 years; mean, 51.2 years) underwent radical resection of extremity sarcomas followed by immediate reconstruction. Seven patients had tumors in the upper extremity and 12 patients had tumors in the lower extremity. There were 13 primary tumors and 6 recurrent tumors. Fifteen patients (79%) received radiation therapy, 7 patients by external beam and 8 patients by brachytherapy. Reconstruction included 16 regional flaps in 13 patients and 7 free tissue transfers in 6 patients. Commonly used flaps included the rectus abdominis (N = 5), the latissimus dorsi (N = 4), the anterolateral thigh (N = 4), the reverse flow radial forearm (N = 2), and the gastrocnemius (N = 2) flaps. Complications included wound breakdown (N = 2), partial skin graft failure (N = 1), hematoma requiring operative evacuation (N = 1), and partial flap necrosis (N = 1). There were no operative mortalities. Eight patients underwent wide local excision, flap closure, and brachytherapy. Mean length of hospital stay for this group was 12.3 days compared with 13.8 days for the remaining 11 patients. There was one complication (13%) in this group and four complications in the remaining patients (4 of 11; 36%). Our study confirms the utility of soft-tissue reconstruction to permit wide local excision with clear margins as well as the delivery of postoperative radiotherapy. It demonstrates the ability of pedicled flaps and free tissue transfers to remain viable and provide sufficient wound coverage in the setting of early postoperative brachytherapy. In addition, this series illustrates the efficacy of a team approach and one-stage therapy for extremity soft-tissue sarcomas that includes excision, reconstruction, and early postoperative brachytherapy in a single hospitalization. PMID- 9374141 TI - A comparison of donor and recipient site sensation in free tissue reconstruction of the oral cavity. AB - In patients who undergo oral cavity reconstruction, loss of sensation plays a vital role in producing disturbances in postoperative oral function. Microsurgical techniques have provided a method of addressing this deficit through the use of sensate cutaneous free flaps in which microneural anastomoses are performed between a sensory nerve supplying the flap, and a recipient nerve in the head and neck. The purpose of this study was to compare the cutaneous sensation of the radial forearm flap and lateral arm flap donor sites, the two most commonly used intraoral sensate flaps. For comparison, sensation was also determined in five intraoral sites: the tip of tongue, lateral tongue, cheek, gingiva, and hard palate. Sensation was evaluated at the two potential donor sites in 66 random subjects using static and moving two-point discrimination, thermal sensation differences, and Semmes-Weinstein monofilament pressures. In the same subjects Semmes-Weinstein monofilament pressures were used to evaluate intraoral sensation. Information was recorded on age, sex, smoking and denture status. All four sensory evaluations demonstrated that the lateral arm flap donor site was more sensitive than the radial forearm donor site. Thermal sensitivity differentials (0.52 vs. 0.40 degrees C, p < 0.001), static two-point discrimination (15.4 vs. 15.0 mm, p < 0.2), moving two-point discrimination (5.8 vs. 4.8 mm, p < 0.03), and Semmes-Weinstein monofilament pressures (5.10 vs. 4.08 g per square millimeter, p < 0.001) all indicated a more sensitive lateral arm flap donor site. Older subjects had significantly decreased sensation at both donor sites based on static two-point discrimination and Semmes-Weinstein monofilament testing. No sex differences were noted. Based on Semmes-Weinstein monofilament testing in the mouth, the tip of the tongue is the most sensitive area (2.26 g per square millimeter), followed by the hard palate (3.60 g per square millimeter), the lateral tongue (4.08 g per square millimeter), the cheek (4.77 g per square millimeter), and the gingiva (8.06 g per square millimeter). Smokers had significantly decreased sensation at the tip of tongue and hard palate. Denture wearers had significantly diminished sensation in all intraoral locations except the lateral tongue. Older patients had significantly diminished sensation at all intraoral sites. No sex differences were noted. The lateral arm flap donor site is a more sensitive region than the radial forearm flap donor site. However, the lateral arm flap donor site is less sensitive than the tip of tongue and hard palate, while the radial forearm flap donor site is less sensitive than the tip of tongue, hard palate, lateral tongue, and cheek. This suggests that for certain locations, intraoral sensate flaps may require measures such as sensory reeducation protocols to approach normal recipient site sensation. PMID- 9374142 TI - Recurrent carpal tunnel syndrome following endoscopic carpal tunnel release: a preliminary report. AB - Persistent or recurrent symptoms following endoscopic carpal tunnel release have been reported in 0.5% to 3% of patients undergoing this procedure. Unfortunately, preoperative risk factors for this complication have not been defined. We reviewed the records of 126 consecutive patients who underwent Agee single-portal endoscopic carpal tunnel release between June 1994 and March 1997. Five patients and six hands required subsequent open carpal tunnel release for persistent or recurrent carpal tunnel syndrome. Fulminant synovitis was identified during open carpal tunnel release in all reexplored patients, and four of the six hands were cured with open release and synovectomy. No recurrences were identified in the group of patients who presented with unilateral carpal tunnel syndrome. The presence of bilateral carpal tunnel syndrome may be a risk factor for persistent or recurrent carpal tunnel syndrome following endoscopic carpal tunnel release. PMID- 9374143 TI - The effects of tissue expansion on the hemodynamic and survival characteristics of reverse-flow island flaps: an experimental study in rabbits. AB - The effects of tissue expansion on the hemodynamic and survival characteristics of reverse-flow island skin flaps were investigated in New Zealand White rabbits. The animals were divided into 3 groups of 15: group I (control) had no surgery prior to flap elevation, group II (nonexpansion) had a noninflated expander, and group III (expansion) had an inflated expander of 80 ml. After 3 weeks of expansion, a reverse-flow island flap based on the distal saphenous pedicle was elevated. A series of hemodynamic studies was performed to test reverse venous flow--in particular, valve competence. Besides observing the reverse flow under an operating microscope, the changes in the intravenous pressure were measured at 0, 5, 15, 30, 60, and 120 minutes after flap elevation. Moreover, reverse-flow resistance (RFR) was measured in each group to test the competence of venous valves. At each time interval, the values of intravenous pressure were significantly lower (p < 0.01) in group III than in the groups I and II. However there was no statistically significant difference between group I and group II. The RFR was measured as 126.7 +/- 33.52 mmHg in group I, 59.3 +/- 29.86 mmHg in group II (p < 0.01), and 25.1 +/- 7.68 mmHg in group III (p < 0.01). Ten days after flap elevation the mean survival of group III (100%) was statistically higher than that of group I (57.4 +/- 18.3%; p < 0.01) and group II (81.6 +/- 12.8%; p < 0.05). These findings simply suggest that controlled tissue expansion improves retrograde venous drainage and increases the survival of reverse-flow island flaps in rabbits. Abnormal dilatation of the venous tree and incompetence of the venous valves seem to be the main factors in explaining the decrease in the values of RFR and intravenous pressure in the expanded flaps. The potential mechanisms to explain the effects of tissue expansion, and the clinical implications are discussed. PMID- 9374144 TI - Treatment of giant congenital nevi with cryopreserved allogeneic skin and fresh autologous cultured epithelium. AB - Giant congenital nevi, confluent over 10% to 52% of the body surface area, were treated in 5 pediatric patients with allogeneic skin and autologous cultured epithelium (ACE). The lesions were excised to the adipose tissue and the wound was covered with cryopreserved or fresh allografted skin. Later, the skin surface was abraded and ACE was applied. The size of the cultured graft ranged from 360 to 900 cm2 (average, 630 cm2). In 3 patients the wounds healed well. Allograft cryopreservation averaged 50 days. The average interval to ACE application after skin grafting was 10 days. Histological rejection was minimal. In 2 patients the cultured grafts did not take. The wounds were covered with split-thickness skin grafts. In one such patient, a fresh allograft was used. In the other, ACE was applied 27 days after skin grafting. Vigorous rejection reaction was observed. Cryopreservation of allogeneic skin may be important in the treatment of human leukocyte antigen-mismatch patients with giant nevi, and ACE should be applied within 10 days of skin grafting. PMID- 9374145 TI - Treatment of giant pigmented nevus using artificial dermis and a secondary skin graft from the scalp. AB - From January 1994 to October 1995, 5 patients with congenital giant pigmented nevi were treated using artificial dermis with a secondary skin graft from the scalp. The nevus was excised in full thickness and the open wound was grafted with artificial dermis. About 3 weeks later, thin split-thickness skin grafting on the newly synthesized, dermis-like tissue was required. We chose the scalp as the donor of the secondary skin graft. Epithelialization of each donor site was completed within 1 week. In addition, the donor site was not complicated with alopecia or hypertrophic scars. Morbidity at the donor site was minimized and favorable tissue quality of the grafted skin was obtained. The clinical results revealed that the scalp was a favorable donor of a secondary skin graft for the treatment of giant pigmented nevus with artificial dermis. PMID- 9374146 TI - A new experimental model: the vascular pedicled cutaneous flap over the mid dorsum of the rat. AB - The cutaneous vascular anatomy of the mid-dorsum in the rat and its role in flap design was studied in the rat. The investigation consisted of anatomic dissection, methylene blue injection into the axial artery, and flap harvesting in live animals. Dissection and injection revealed that the mid-dorsum of the rat derives its blood supply largely from the 10th intercostal artery, here referred to as the middle dorsal artery, which originates from the lateral aspect of the thoracic aorta. The cutaneous vascular territory of the middle dorsal artery was defined as follows: the medial border, midline of the dorsum; the lateral border, midaxillary line; the cephalic border, a line joining the medial and lateral borders midway between the level of the axilla proximally and 1 cm above the base of the rib cage distally; and the caudal border, a line drawn midway between the latter point proximally and the anterior superior iliac spine distally. Both unilateral and bilateral vascular pedicled island cutaneous flaps were harvested in living rats based on and exceeding the vascular territory delimited by methylene blue injection. Flaps limited to this territory with intact middle dorsal arteries showed total survival, while oversized flaps underwent partial necrosis peripherally. Because of its simplicity, reliability, and consistent vascularity, this flap has potential applications in the study of flap hemodynamics. PMID- 9374147 TI - Modification in flap design of the epigastric artery flap in rats--a new experimental flap model. AB - The standard rat epigastric artery flap has been a very reliable model for flap research. The purpose of this study was to describe a modified design of this flap that included only the medial branch of the epigastric artery. Axial-pattern epigastric island skin flaps, measuring 8 x 8 cm, were raised in two groups of Sprague-Dawley male rats. In group A (N = 20) the vascular pedicle consisted of the main trunk of the epigastric vessel and both medial and lateral branches. In group B (N = 20) the flap was based solely on the medial branch of the epigastric artery, excluding the large lateral branch. The flaps were elevated and then sutured back to their beds. Flap survival was studied and the amount of viable skin in both groups was compared 1 week later. The rats were photographed using a digital camera and the images were analyzed using imaging software. The mean percentage surviving flap area in group A was 86.24% and in group B it was 69.72%, which is statistically significant (p < 0.001). We believe that this flap model, with its new modified design that includes a larger flap and inclusion of only the medial branch, will broaden its application to microsurgery. The main advantage of this flap over the conventional epigastric flap is that in this model it is possible to achieve predictable and consistent necrosis in the random extension of the flap. PMID- 9374149 TI - Oxygen free radicals impair wound healing in ischemic rat skin. AB - Oxygen free radicals are produced and play an important role in ischemic injury. We therefore wished to investigate the role of free radicals on ischemic skin wound healing. For this purpose, H-shaped flaps, where the test ischemic wound is the horizontal line in the H, were created on the dorsum of the rat. To inhibit the probable hazards of free radicals, allopurinol and superoxide dismutase (SOD) were given to the animals. Most of the studied wound-healing parameters were impaired in the ischemic group. In the allopurinol-treated group, breaking strength was increased by 52% by day 7 and by 109% by day 14 (p < 0.0002 and p < 0.001), and in the SOD-treated group the increase was 69% both by days 7 and 14 of healing when compared with the ischemic control group (p < 0.003 and p < 0.002). Hydroxyproline content was increased 75% with allopurinol and 113% with SOD in the wound by day 7 (p < 0.03 and p < 0.001 respectively). SOD treatment caused a significant decrease in wound edema by day 7 of healing (p < 0.05). Histopathological evaluation revealed that in the SOD- and allopurinol-treated groups, the amount of collagen and its organization were more prominent when compared with the ischemic controls. These results show that oxygen free radicals play an important role in the failure of ischemic wound healing, and antioxidants partly improve the healing in ischemic skin wounds. PMID- 9374148 TI - Involvement of neutrophils in ischemic injury. I. Biochemical and histopathological investigation of the effect of FK506 on dorsal skin flaps in rats. AB - The purpose of this study was to investigate the role of neutrophils in ischemic tissue injury and the possible inhibition by pretreatment with FK506, a neutrophilic modulating agent. A dorsal caudally based skin flap (3 x 9 cm) was used as an ischemic injury model in experimental groups. Prior to flap elevation, FK506 at doses of 0.3 mg per kilogram (group 2), 0.5 mg per kilogram (group 3), and 1.0 mg per kilogram (group 4) was given for 3 days intramuscularly. The relationship among neutrophil accumulation (histopathologically), myeloperoxidase (MPO) activity, malondialdehyde (MDA) content (biochemically) of the flap tissue, and flap survival were studied. Skin flaps showed reduced necrosis in the FK506 treated groups (p < 0.08, p < 0.0001, and p < 0.0001 respectively). The increase in accumulation of neutrophils, and MDA and MPO levels (which were induced by ischemia) observed 1 and 24 hours after flap elevation was diminished by FK506 pretreatment. The increased neutrophilic infiltration, and raised tissue MDA content and MPO activity revealed involvement of both free radical production and neutrophils in ischemia. This injury was decreased by FK506, probably by inhibition of neutrophilic chemotaxis, infiltration, and releasing factors. PMID- 9374150 TI - Effects of vasoactive medications on the blood flow of island musculocutaneous flaps in swine. AB - Pedicled flaps and microsurgical free tissue transfers are increasingly being used for reconstruction in the elderly and poorer risk patient. The use of systemically administered vasoactive agents to date has been avoided because of the fear that systemic levels of these agents perioperatively (particularly the vasopressors) might decrease blood flow and compromise the viability of the flap. There are no large-animal, real-time hemodynamic studies that support or disprove this belief. The objectives of this study were to (1) develop a musculocutaneous flap model in the pig that allows accurate, simultaneous monitoring of systemic and flap hemodynamic parameters such as flow and resistance and (2) identify the effects of commonly used vasoactive substances (dopamine, dobutamine, and phenylephrine) at clinically used levels on systemic and flap pressure/flow relationships. Vertically based rectus abdominis musculocutaneous flaps were raised in 8 anesthetized, 50- to 55-kg pigs, and a flow probe was placed around the artery. Catheters within the pulmonary artery and aorta were used to measure cardiac output and aortic root pressures. Measures of arterial blood pressure, cardiac output, and musculocutaneous flap flow were obtained at baseline and during the administration of varying doses of dopamine dobutamine and phenylephrine. Cardiac output increased significantly with low and high doses of dopamine and dobutamine, but decreased with increasing doses of phenylephrine. Flap flow, on the other hand, is increased only with dobutamine but remains unchanged with dopamine despite increased cardiac output. Flap flow decreases with high doses of phenylephrine. Flap flow also decreases relative to cardiac output with both dopamine and dobutamine. We conclude that (1) phenylephrine clearly affects flap flow adversely in a large-animal musculocutaneous model and therefore should be avoided, (2) dopamine does not affect total flap flow at either low or high doses despite increasing cardiac output, (3) dobutamine increases both flap flow and cardiac output, and (4) both dopamine and dobutamine should still be used with caution because the flap flow is not equally increased relative to total cardiac output. Possible changes in systemic and flap metabolic demand induced by these vasopressor drugs may therefore still be injurious to the flaps. PMID- 9374151 TI - Serum creatine kinase in fasciocutaneous and musculocutaneous flap surgery. AB - The pre- and postoperative serum levels of creatine kinase (CK) were analyzed in 56 patients operated with three different breast reconstructive procedures. Thirteen patients were operated with the lateral thoracodorsal flap (LTD), 23 by the latissimus dorsi flap (LD), and 20 by the pedicled transverse rectus abdominis musculocutaneous (TRAM) flap. Nineteen patients in the LD and TRAM groups had received postmastectomy radiotherapy. The operations caused a significant rise in the serum levels of CK, and the highest levels were found on the first postoperative day: LTD, 5.4 microkat per liter; LD, 8.1 microkat per liter; and TRAM, 7.3 microkat per liter. There was no significant difference in CK levels between the groups. The irradiated patients did not show increased CK levels when compared with nonirradiated patients. PMID- 9374152 TI - Exposure of fibroblasts derived from keloid patients to low-energy electromagnetic fields: preferential inhibition of cell proliferation, collagen synthesis, and transforming growth factor beta expression in keloid fibroblasts in vitro. AB - We studied the effects of electromagnetic fields (EMFs) on cell proliferation and collagen synthesis in both normal and keloid fibroblasts in vitro. Treatment of keloid fibroblasts with 60-Hz EMFs for 10 days resulted in the inhibition of cell proliferation, whereas no significant change in cell proliferation of normal fibroblasts was observed. EMFs inhibited collagen synthesis in keloid fibroblasts but not in normal fibroblasts without altering the ratio of type III to type I collagen, indicating that EMFs inhibit type I and type III collagen synthesis to the same extent. EMFs also decreased the expression of transforming growth factor beta (TGF-beta) in keloid fibroblasts. These results suggest that EMFs may have a useful therapeutic potential for the treatment of keloid. PMID- 9374153 TI - Terra firma forme dermatosis. AB - New pigmented lesions with alarming properties should trigger the responsible physician to perform diagnostic procedures including biopsies, blood tests, and endocrinological evaluations. A unique pigmented dermatosis of unknown etiology, known as terra firma forme dermatosis, creates a cosmetic disturbance that might mislead experienced physicians and trigger unnecessary and expensive workups when all that is needed is a firm rubbing with 70% alcohol-impregnated applicators. We present a 17-year-old girl with such a lesion and discuss the diagnostic possibilities. PMID- 9374154 TI - Hydroxyurea-related ankle ulcers in patients with myeloproliferative disorders: a case report and review of the literature. AB - The association of ankle ulcer development with hydroxyurea therapy in patients with myeloproliferative disorders has been reported in two small case series and two patient reports. It is thought that hydroxyurea, an antineoplastic agent with selective cytotoxicity for cells that divide most actively (such as those of the skin), causes these ulcerations through impairment of normal wound healing in areas of common trauma. Treatment modalities reported include discontinuation of medication, debridement, and topical antibiotics. We report the successful split thickness skin grafting of a hydroxyurea-related ankle ulceration after preoperative discontinuation of hydroxyurea treatment in a patient with chronic myelogenous leukemia who had previously failed grafting while taking this medication. It is hoped that heightened awareness of the link between hydroxyurea and chronic, debilitating ankle ulcerations in patients with myeloproliferative disorders, as well as familiarity with reported treatments, will promote early diagnosis and aggressive management of these unique and relatively uncommon lesions. PMID- 9374155 TI - Saving face. PMID- 9374157 TI - Less common causes of carpal tunnel syndrome. PMID- 9374156 TI - Intralesional hyaluronic acid treatment of pathological scars. PMID- 9374158 TI - Torticollis and traumatic ocular dystopia. PMID- 9374159 TI - Adipofascial flap harvest using endoscopic assistance. PMID- 9374160 TI - Distal dorsal forearm flap. PMID- 9374162 TI - Reporting of results of surgery for conductive hearing loss. PMID- 9374163 TI - Effect of radiotherapy on the levels of secretory immunoglobulin A against indigenous and virulent streptococci. AB - It is well known that the frequency of upper respiratory infection is clinically increased after radiotherapy of the head and neck region. This study found higher antibacterial secretory immunoglobulin A (S-IgA) activity against three indigenous streptococci (Streptococcus mitis, S. salivarius, and S. sanguis I) and S. pneumoniae in patients who had undergone radiation therapy of the head and neck region than in control subjects. This showed no relation to the extent of the radiation field. Compared with before radiotherapy, the S-IgA titer against S. pneumoniae and its ratio to the activities against the indigenous streptococci were significantly higher in patients with fully irradiated major salivary glands. These results indicated that the radiotherapy promoted the antigen specific S-IgA production of virulent streptococci in most patients with head and neck cancer, even more than 6 months after radiotherapy. The resulting altered balance in the S-IgA system of normal indigenous streptococci may also impair the ability to maintain the stable bacterial interference between normal indigenous and virulent streptococci in the oropharyngeal cavity. PMID- 9374164 TI - Surgical anatomy of the rat middle ear. AB - This study was designed to aid experimental otologic studies of the rat middle ear. The topographic anatomy of the albino rat middle ear is described. A set of microphotographs with matching illustrations presents the structural details at several surgical exposures. Anatomic differences between the rat, guinea pig, and cat are noted. PMID- 9374166 TI - Neural cell adhesion molecule in adenoid cystic carcinoma invading the skull base. AB - Neural cell adhesion molecules (N-CAMs) are expressed in neuromuscular tissues, neuroblastoma, and small cell lung carcinoma. Adenoid cystic carcinoma may invade the skull by either direct extension or neural involvement, particularly along the second and third divisions of the trigeminal nerve (V2 and V3). Eighteen patients with adenoid cystic carcinoma that invaded the skull base were studied. The tumors were graded into predominantly solid (3), cribriform (11), or tubular trabecular (4) patterns, and neural involvement was evaluated histologically. Paraffin sections were examined by use of monoclonal antibodies for N-CAM and Ki 67, a proliferation marker, with the avidin-biotin-peroxidase method. Fifteen (83%) tumors showed perineural involvement; in the remaining three cases no nerves were present for histologic examination. Fourteen (93%) of 15 tumors with perineural involvement were reactive with N-CAM. Proliferation, measured by the presence of nuclear Ki-67, was markedly increased in tumors with predominantly solid patterns. We demonstrated that N-CAM is expressed in adenoid cystic carcinoma. The role of N-CAM as a neurodeterminant that facilitates the spread of adenoid cystic carcinoma along nerves, however, remains unanswered and warrants further study. PMID- 9374165 TI - Microsatellite alterations at chromosome 8q loci in pleomorphic adenoma. AB - OBJECTIVE: To determine the extent, localization, and clinical significance of microsatellite loci alterations at sites of reported cytogenetic abnormalities in pleomorphic adenomas. BACKGROUND: Pleomorphic adenoma is a benign salivary gland tumor with a propensity for recurrence and potential for malignant conversion. Although its cause remains unclear, clonal cytogenetic abnormalities have been reported consistently. DESIGN: DNA extracted from paired normal and tumor tissue specimens from 1 patient with carcinoma ex pleomorphic adenoma and 17 patients with pleomorphic adenoma (3 contained foci of carcinoma ex pleomorphic adenoma) was evaluated for loss of heterozygosity at microsatellite loci with a multiplex polymerase chain reaction-based analysis. Correlation with clinical and pathologic features was performed. RESULTS: Overall 10 (56%) of 18 cases manifested loss of heterozygosity at the loci tested. The frequency of loss of heterozygosity noted on 3p, 6q, 8p, 8q, and 12q microsatellite loci was 17%, 12%, 8%, 47%, and 27% of informative cases, respectively. Specimens from patients with carcinoma ex pleomorphic adenoma showed a similar loss of heterozygosity incidence at these loci. No apparent association between molecular abnormalities and clinical-pathologic features was observed in this cohort. CONCLUSIONS: Loss of heterozygosity at microsatellite loci on 8q, a breakpoint at which translocations have been previously documented in pleomorphic adenoma, is a frequent event in this tumor. The incidence is not increased in patients with focal carcinoma ex pleomorphic adenoma, suggesting that loss of heterozygosity at 8q is an early event in tumorigenesis. Further evaluation at these loci is needed to identify potential tumor suppressor genes that may be associated with the initiation and progression of pleomorphic adenomas. PMID- 9374167 TI - Otitis media incidence and impact on the auditory brain stem response in lipopolysaccharide-nonresponsive C3H/HeJ mice. AB - Although mice of the C3H strain normally respond to bacterial lipopolysaccharide with appropriate immune system activation, mice of the C3H/HeJ substrain do not because of a gene defect. This suggests they may be more susceptible to opportunistic bacterial infections and more likely to have otitis media than a normally responding substrain, such as the C3H/HeSnJ. Therefore these two substrains were evaluated for incidence of spontaneous middle ear disease at 2, 4, 6, 10, 12, 15, and 18 months of age. Auditory brain stem response audiometry to pure tones of 4, 8, 16, 24, and 32 kHz was performed to establish the impact of middle ear disease on auditory function. None of the lipopolysaccharide responsive C3H/HeSnJ mice demonstrated middle ear disease. However, middle ear disease was present in 33% of the C3H/HeJ mice. The conductive loss caused by the otitis media resulted in auditory brain stem response threshold shifts of 15 to 40 dB SPL, lowered peak amplitudes, and increased latencies. Reduced lipopolysaccharide responsiveness by C3H/HeJ mice makes them less capable of reacting immunologically to bacterial infection and presumably underlies the failure to clear middle ear disease. The C3H/HeJ mouse may provide a valuable model in which to study lipopolysaccharide biologic activity and related middle ear inflammatory or immune mechanisms. PMID- 9374168 TI - Lipoinjection in the paralyzed feline vocal fold: study of graft survival. AB - Six adult domestic strain cats were used to study the long-term histologic outcome of injected autologous fat for augmentation of the paralyzed vocal fold. Each animal had surgically induced left vocal cord paralysis via sectioning of the recurrent laryngeal nerve, followed by injection of 0.1 to 0.2 ml of autologous fat into the paralyzed vocal fold. The animals were killed at 6 weeks, and at 4, 6, 8, and 12 months after the injection. Photographic and videolaryngoscopic data were obtained. Histologic studies of the larynges were performed. The results documented histologic viability and persistence of a portion of the injected adipose tissue graft at 8 months after the injection, but only minimal graft survival at 12 months. The outcome suggests that autologous lipoinjection has potential use for short-term (several months) augmentation of the paralyzed vocal cord. Further investigation is warranted before recommending this technique for such use or as an alternative to currently available long-term injectable laryngeal biomaterials. PMID- 9374170 TI - Nebulized surfactant for experimentally induced otitis media with effusion. AB - Eustachian tube dysfunction frequently results in clinical evidence of otitis media with effusion (OME). Surface active substances, surfactants, are hypothesized to play a role in normal eustachian tube function. Recent work in a rodent model has demonstrated improved eustachian tube function with topical application of surfactants to the middle ear. A novel, noninvasive, and clinically practical method of delivering surfactant to the eustachian tube was studied in a gerbil model of OME. Otitis media with effusion was experimentally induced in 20 gerbils by transtympanic inoculation of heat-killed Streptococcus pneumoniae. This represents a well established model for creating a serous effusion in the gerbil that significantly increases eustachian tube opening pressure. Effusion developed in 27 of 40 ears (67.5%) after inoculation. An inhaled nebulized surfactant was used to treat the animals with microscopically confirmed OME in one or both ears. The treatment period was 5 days. Eustachian tube opening studies were performed on both affected and nonaffected animals. Successful eustachian tube opening pressures were obtained in 30 of 36 ears (83.3%). The mean opening pressure for ears without effusion (healthy ears) was 42.8 mmHg. The mean opening pressure for ears with effusion in animals treated with nebulized surfactant was 41.4 mmHg. The difference between these mean values was not statistically significant (t = 0.32; p > 0.50). This pilot study suggests that inhaled nebulized surfactant may be efficacious in treating eustachian tube dysfunction when manifested in disorders such as OME. PMID- 9374169 TI - Comparison of mRAST and CAP with skin end point titration for Alternaria tenuis and dermatophagoides pteronyssinus. AB - There has been a recent explosion of new in vitro tests for the diagnosis of allergies. At present there is no general agreement on which type of in vitro test is best. Recently our hospital switched in vitro testing from the modified radioallergosorbent system (mRAST) to the Pharmacia CAP system (CAP). While changing in vitro testing techniques, 47 patients were tested with both the mRAST and CAP tests. Comparisons were made between the mRAST and CAP results of Alternaria tenuis and Dermatophagoides pteronyssinus allergens. These results were then compared with the results of patients who also underwent intradermal skin testing based on end point titration techniques. PMID- 9374171 TI - Regulation of mucin secretion in the ferret trachea. AB - Mucin is the major component of mucus and can be used as a marker for mucus secretion. The purpose of this study was to develop an in vitro method to evaluate the regulation of mucin secretion. To do this, we used a sandwiched enzyme-linked lectin assay to measure mucin secretion from isolated ferret tracheal segments. This assay entailed coating microtiter plate wells with dolichos biflorus agglutinin and detecting the bound mucin that was secreted into a buffer solution by the tracheal segments. We used this method to evaluate the secretory response to four secretagogues: prostaglandin F2alpha (PGF2alpha), adenosine triphosphate (ATP), methacholine, and human neutrophil elastase (HNE). Each agent stimulated mucin secretion above baseline secretion (ATP (p = 0.022), PGF2alpha (p = 0.009), and HNE (p < 0.05)), and the relative potency of these secretagogues was PGF2alpha < or = ATP < MCh < HNE. We also demonstrated that there is an anatomic gradient for both constitutive and stimulated mucin secretion, with the distal tracheal segments secreting more mucin per gram of weight than the proximal segments. This fairly simple and reproducible technique can be used to evaluate the regulation of mucin secretion in the airway and to assess the efficacy of agents that might alter the secretory response. PMID- 9374172 TI - A comparison of methods of botulinum toxin injection for abductory spasmodic dysphonia. AB - Treatment of abductory spasmodic dysphonia with botulinum toxin injection into the posterior cricoarytenoid muscles often results in only partial symptom relief. In contrast, excellent results can be achieved after thyroarytenoid injection for the adductory type of spasmodic dysphonia. One reason for disappointing results may be inaccurate placement of the botulinum toxin into the posterior cricoarytenoid muscles. We describe a new approach to posterior cricoarytenoid injection used in 18 patients for treatment of abductory spasmodic dysphonia. Of the 30 patients treated for abductory spasmodic dysphonia at Loyola University-Chicago, 6 underwent both a retrocricoid approach and the newer transcricoid method, thus allowing patient and clinician comparison of techniques. We and all six of our patients preferred the transcricoid approach because of less discomfort, equivalent or better voice results, and fewer side effects. PMID- 9374173 TI - Comparison of five agents in protecting the cochlea against the ototoxic effects of cisplatin in the hamster. AB - The purpose of this investigation was to study the ameliorating effects of four agents on cisplatin-induced ototoxicity. Hamsters were given a series of five cisplatin injections either alone or in combination with sodium thiosulfate (STS), diethyldihydrothiocarbamate (DDTC), and S-2(3-aminopropylamino) ethylphosphorothioic acid (WR-2721), or fosfomycin. Ototoxicity was assessed anatomically by quantifying the extent of cochlear damage with the scanning electron microscope and physiologically with measures of the auditory brain stem response. When administered alone, cisplatin induced widespread loss of outer hair cells (OHCs) along much of the cochlea in the hamster, especially in the basal and middle turns, with an average survival of only 56% of the OHC population. In contrast, inner hair cells resisted cisplatin ototoxicity in the hamster. Thus the ameliorative effects of the different test agents were assessed by counting the number of surviving OHCs in each treatment group and comparing with cisplatin-treated controls. STS provided the most effective protection against the ototoxic effects of cisplatin, yielding 91% survival of OHCs. DDTC also reduced the ototoxic effects of cisplatin, yielding 68% survival of OHCs. Cotreatment with WR-2721 and fosfomycin yielded 45% and 52% OHC survival, respectively, and thus did not provide any chemoprotection. The results closely paralleled those based on auditory brain stem response recordings in that the magnitude of threshold shift was proportional to the amount of OHC loss; also, the amount of threshold shift at each frequency was in good agreement with the pattern of hair cell loss along the cochlear spiral. Thus both histologic and physiologic results suggest that STS and DDTC hold promise for ameliorating the ototoxic effects of cisplatin chemotherapy. PMID- 9374174 TI - Comparison of nuclear DNA content in locally invasive and noninvasive papillary carcinoma of the thyroid gland. AB - Extrathyroidal invasion of papillary carcinoma of the thyroid gland has a very bad prognosis. A retrospective study was performed on 40 specimens from patients with papillary carcinoma of the thyroid gland to find out whether DNA ploidy correlated with aggressive tumor behavior. The nuclear DNA content of 20 locally aggressive papillary thyroid carcinomas was studied by flow cytometry. The results were compared with those of a matched control group of 20 patients with noninvasive papillary tumors. Forty percent of the tumors with spread to extrathyroid tissue were aneuploid, whereas all the tumors without such extension were diploid. This difference was statistically significant (p < 0.003). The data suggest that the differentiation of locally noninvasive and invasive papillary thyroid carcinomas may be potentially possible by nuclear DNA determination. PMID- 9374175 TI - Cochlear immunoglobulin in the C3H/lpr mouse model for autoimmune hearing loss. AB - Immunoglobulin staining was conducted in cochlear tissue from the C3H/lpr autoimmune strain mouse to better understand the local immune processes underlying autoimmune inner ear disease. This mouse is a model for spontaneous systemic lupus erythematosus with coincident elevated cochlear thresholds. Cochleas were examined from C3H/lpr mice at 2 months of age, before disease onset, and at 8 months of age, when systemic disease and hearing loss are manifested. Sections of these cochleas, along with cochlear sections from age matched C3H/HeJ nonautoimmune controls, were immunocytochemically stained for IgG and IgM to identify areas of abnormal immunoglobulin activity. IgM immunoreactivity was similar in control and autoimmune cochlear tissue and did not appear to vary with disease progression. Staining was limited to the inside of capillaries in the stria vascularis and other areas within the cochlea. Similar staining patterns were seen in control animals stained for IgG. However, C3H/lpr mice with autoimmune disease showed extensive IgG immunoreactivity spreading out from the stria vascularis capillaries into the extracapillary spaces. This increased permeability suggested that breakdown of the blood labyrinth barrier was coincident with systemic autoimmune disease. PMID- 9374176 TI - Triple semicircular canal occlusion in the guinea pig. AB - Hearing preservation is possible with translabyrinthine procedures, but the optimal means of sealing the remaining labyrinth has not been determined. The purpose of this study was to compare the effects of mechanical and nonmechanical (CO2 laser-assisted) triple semicircular canal occlusion on hearing in the guinea pig. All three semicircular canals of 19 guinea pigs were treated with one of four techniques: fenestration without packing (control), fenestration with packing, CO2 laser coagulation of the membranous canal without packing, or laser coagulation with packing. Six weeks postoperatively, electrocochleographic thresholds were significantly elevated in one of five ears treated with packing alone, in one of five ears treated with laser and packing, in two of five ears treated with the laser alone, and in all four control ears. Thresholds were significantly elevated in control versus occluded ears (p < 0.05). There were no significant differences between the ears treated with laser or packing. These findings suggest that hearing can be preserved in triple canal occlusion by means of sealing the membranous labyrinth with either CO2 laser coagulation or mechanical packing. Further study on the feasibility of hearing preservation with complete labyrinthectomy is warranted. PMID- 9374177 TI - Prevalence of mold-specific immunoglobulins in a Midwestern allergy practice. AB - Mold allergy surveys are an important part of the correct identification and treatment of mold allergies. This study included 100 patients who were referred to a Midwestern allergy clinic for the evaluation of rhinitis, suspected to be of allergic origin. An in vitro screening test for allergen-specific IgE (ImmunoCAP) comprised of 10 allergens, including Candida, Aspergillus, Helminthosporium, and Alternaria, was used. To assess the seasonal distribution of mold allergies, we randomly selected 8 patients out of the 100 from each season during which the clinical contact occurred, and we tested them for 14 varieties of mold. The overall incidence of mold allergy in atopic subjects was 44%. The most common molds were (in descending order of frequency) Alternaria, Helminthosporium, Aspergillus, Candida, and Curvularia. Mold allergy was diagnosed most frequently in the winter; the second highest period was the fall. Population surveys of IgE antibody sensitization by in vitro techniques can provide useful information about fungal allergy. PMID- 9374178 TI - Effects of stimulus intensity on laryngeal long latency responses in awake humans. AB - Percutaneous electrical stimulation applied to the internal branch of the superior laryngeal nerve (ISLN) results in two long latency laryngeal adductor responses in awake humans: an ipsilateral thyroarytenoid (TA) R1 muscle response at 16 ms, and later bilateral TA R2 muscle responses at 60 ms. The purpose of this study was to determine whether a functional relationship existed between the R1 and R2 responses by gradually increasing the level of electrical stimulation from threshold to supramaximal levels. R1 amplitude increased linearly with stimulation intensity in 9 of the 11 subjects, whereas R2 only had a positive linear relationship in 3 subjects and a negative relationship with stimulation intensity in 1 subject. Significant negative relationships were found between response latency and stimulation intensity in 3 subjects for the R1 responses and 3 other subjects for the R2 responses. Overall, R1 amplitudes increased systematically, whereas R2 responses varied in latency and amplitude with increasing stimulus intensity. Neither the latencies nor the amplitudes of the two responses were related after adjusting for stimulation intensity within subjects by using partial correlation coefficients. The R1 and R2 responses were functionally unrelated and most likely have different neural components. PMID- 9374179 TI - Breakdown of stria vascularis blood-labyrinth barrier in C3H/lpr autoimmune disease mice. AB - Sensorineural hearing loss related to autoimmune disease is a well-recognized condition, although the exact pathophysiologic mechanisms remain unclear. One current theory postulates immune complex-induced interference with blood labyrinth barrier integrity in the stria vascularis. The C3H/lpr autoimmune mouse was chosen to study the permeability of capillaries in the stria vascularis because this mouse model has demonstrated abnormalities of the stria vascularis and shifts in the auditory brain stem response threshold during active disease. C3H/lpr mice with active disease were compared with younger mice without disease, as well as age-matched C3H/HeJ control mice. The mice were injected with the tracer ferritin and examined by transmission electron microscopy to evaluate the integrity of the capillary tight junctions in the stria vascularis. Four of five mice with active disease were noted to have extensive leakage of ferritin into the perivascular tissues. Neither the young, disease-free autoimmune mice nor the nonautoimmune control mice demonstrated vessel leakage. Thickening of the basement membrane was also noted in the diseased animals. The results imply that active disease leads to a breakdown in the blood-endolymph barrier, which could underlie the hearing loss accompanying autoimmune and other immune diseases. PMID- 9374181 TI - Cerebrospinal fluid fistulae in a canine model. AB - Various diagnostic techniques currently are used to detect the presence of a cerebrospinal fluid fistula. High resolution computerized tomography scanning with the instillation of an intrathecal nonionic contrast medium yields the most accurate diagnostic results. Occasionally, even with optimal conditions, little information is gained other than the confirmation of the presence of a fistula. Intrathecal fluorescein can provide accurate information on the exact location of the fistula. The current study was designed to refine the clinical examination for cerebrospinal fluid fistulae with the use of intrathecal fluorescein. The canine model that we used also served as a vehicle to investigate the histopathologic effects of fluorescein on the central nervous system. We modified a commonly used xenon light source to enable examination with 490 nm light. In the canine model, this allowed accurate visualization of surgically created fistulae using very low doses of intrathecal fluorescein. An examination of the histopathologic features of the central nervous system of the canine model after acute instillation of a higher dose of fluorescein revealed microscopic changes consistent with the introduction of an irritant material. The changes induced by the chemical trauma may explain the serious neurologic sequelae sometimes seen in patients after the instillation of intrathecal fluorescein. Recommendations on the correct dosage of intrathecal fluorescein for diagnosis of cerebrospinal fluid fistulae are proposed. PMID- 9374180 TI - Interleukin-8 expression in human nasal polyps. AB - The cytokine interleukin 8 (IL-8) has been shown to be a potent mediator of leukocyte recruitment and neovascularization in inflammatory and neoplastic diseases. In this study we hypothesize that IL-8 produced in the nasal polyp microenvironment is responsible for the leukocyte recruitment seen in nasal polyposis. To test this hypothesis we evaluated nasal polyps for distribution and content of IL-8 antigen with immunohistochemical techniques and radioimmunoassay to determine tissue levels of IL-8. The immunohistochemical results demonstrated that IL-8 antigen staining occurred predominantly within inflammatory cells and epithelium. IL-8 was detected in all nasal polyp tissue homogenates (a mean value of 1767 +/- 1633 pg/mg total protein (TP) with a range of 134 to 3668 pg/mg TP vs control specimens with a mean value of 77 pg/mg TP with a range of 0.09 to 255 pg/mg TP). These data demonstrate the presence and distribution and levels of IL 8 antigen in nasal polyps in vivo, supporting our hypothesis that local production of IL-8 could be an important factor in the sustained recruitment of leukocytes in nasal polyposis. Thus IL-8 likely plays a significant role in the pathogenesis of this disease process and therefore is a potential target for therapeutic intervention. PMID- 9374182 TI - The clavipectoral osteomyocutaneous free flap. AB - Microvascular free tissue transfer has revolutionized head and neck reconstruction and currently is considered the most successful and reliable method of primary oromandibular reconstruction. This study was designed to assess the feasibility of full thickness free vascularized transfer of the clavicle based on the clavicular branch of the thoracoacromial artery and the soft tissue component associated with the thoracoacromial axis. Forty dissections of the pectoral region were performed on 26 cadavers. The anatomic relations of the region and the thoracoacromial arterial and venous systems were documented in detail. Selective ink injections of the thoracoacromial arterial branches were also performed on fresh cadavers. The clavicle was supplied mainly by the clavicular artery (medial three quarters), with minor contribution from the deltoid artery (lateral quarter). An average of 16.1 cm (range of 12 to 20 cm) was obtained with total clavicular harvest and the clavicle had sufficient width and height to support dental implants. Two soft tissue donor sites were associated with the thoracoacromial artery: the sternocostal head of the pectoralis major muscle, with the overlying skin supplied by the pectoral artery, and the clavicular head of the pectoralis major muscle, with the overlying skin supplied by the deltoid and clavicular arteries. Sensory innervation of the upper chest was supplied through the supraclavicular nerves, whereas the lateral pectoral nerve supplied motor innervation to both heads of the pectoralis major muscle. The anatomy of the clavipectoral donor site and the first case of full thickness free clavicular transfer for mandibular reconstruction in the English literature are presented. The donor site is an excellent source of well vascularized, thin, pliable, hairless, potentially innervated (motor and sensory) soft tissue, along with up to 20 cm of clavicular bone. The surgical anatomy is familiar to the head and neck surgeon. The harvesting does not require repositioning of the patient and is amenable to a two-team, simultaneous approach. The functional and cosmetic donor site morbidity is minimal even with clavicular harvest. The major disadvantage of this flap is the relatively short pedicle. The authors conclude that the thoracoacromial system provides a free flap with osseous and soft tissue components that are well suited for oromandibular reconstruction. PMID- 9374183 TI - Drill-induced hearing loss in the nonoperated ear. AB - The reversible hearing loss in the nonoperated ear noted by patients after ear surgery remains unexplained. This study proposes that this hearing loss is caused by drill noise conducted to the nonoperated ear by vibrations of the intact skull. This noise exposure results in dysfunction of the outer hair cells, which may produce a temporary hearing loss. Estimations of outer hair cell function in the nonoperated ear were made by recording the change in amplitude of the distortion-product otoacoustic emissions before and during ear surgery. Reversible drill-related outer hair cell dysfunction was seen in 2 of 12 cases. The changes in outer hair cell function and their clinical implications are discussed. PMID- 9374184 TI - Serial gadolinium-enhanced magnetic resonance imaging and assessment of facial nerve function in Bell's palsy. AB - Eleven patients with mild or moderate acute idiopathic peripheral facial palsy, so-called Bell's palsy, were serially examined by gadolinium-DTPA-enhanced MRI on mean days 11, 40, and 97 (third examination, n = 10) after the onset of palsy. Results of the clinical and neurophysiologic assessment of facial nerve function were compared with the gadolinium-enhanced MRI findings. Eight of the 11 patients demonstrated contrast enhancement of the facial nerve at the initial examination, but in 7 of them, the enhancement had disappeared by the time of the serial follow-up gadolinium-enhanced MRI scans. The disappearance of facial nerve enhancement was found to be related to clinical and neurophysiologic improvements in facial nerve function during recovery from Bell's palsy. The three patients whose scans were negative at the initial gadolinium-enhanced MRI examination had the same clinical severity of palsy, but initially they had milder neurophysiologic involvement than those who demonstrated enhancement; these three patients did not exhibit enhancement at serial follow-up scans. These findings indicate that the presence of enhancement at the initial MRI scan is not necessarily indicative of a poor prognosis for recovery. PMID- 9374185 TI - Evaluation of facial palsy by moire topography index. AB - We investigated the usefulness of moire topography for evaluating facial nerve function in 51 patients with facial palsy and 10 normal volunteers. This method visualizes the shape of objects in three dimensions. We devised three moire indexes as a simple method of quantifying the severity of facial palsy: the nasolabial groove moire index, the oral angle moire index, and the inner canthus moire index. We compared the results obtained by the moire indexes with findings obtained using the House-Brackmann grading system and found that they were highly correlated. These three moire indexes included all the standard factors of the House-Brackmann grading system, allowing us to develop the total moire index. PMID- 9374186 TI - Clinical photographs. Hemangioma of the middle ear. PMID- 9374187 TI - Differential intracellular regulation of cortical GABA(A) and spinal glycine receptors in cultured neurons. AB - Using patch-clamp techniques we studied several aspects of intracellular GABA(A) and glycine Cl- current regulation in cortical and spinal cord neurons, respectively. Activation of PKA with a permeable analog of cyclic AMP (cAMP) produced a potentiation of the Cl- current activated with glycine, but not of the current induced with GABA. The inactive analog was without effect. Activation of PKC with 1 microM PMA reduced the amplitude of the GABA(A) and glycine currents. Internal application of 1 mM cGMP, on the other hand, had no effect on the amplitude of either current. The amplitude of these inhibitory currents changed slightly during 20 min of patch-clamp recording. Internal perfusion of the neurons with 1 microM okadaic acid, a phosphatase inhibitor, induced potentiation in both currents. The amplitude of GABA(A) and glycine currents recorded with 1 mM internal CaCl2 and 10 mM EGTA (10 nM free Ca2+) decayed by less than 30% of control. Increasing the CaCl2 concentration to 10 mM (34 microM free Ca2+) induced a transient potentiation of the GABA(A) current. A strong depression of current amplitude was found with longer times of dialysis. The glycine current, on the contrary, was unchanged by increasing the intracellular Ca2+ concentration. Activation of G proteins with internal FAl4- induced an inhibition of the GABA(A) current, but potentiated the amplitude of the strychnine-sensitive Cl- current. These results indicate that GABA(A) and glycine receptors are differentially regulated by activation of protein kinases, G proteins and Ca2+. This conclusion supports the existence of selectivity in the intracellular regulation of these two receptor types. PMID- 9374189 TI - Effect of tacrine on intracellular calcium in cholinergic SN56 neuronal cells. AB - We have found earlier that the depolarization-induced release of acetylcholine from the brain could be inhibited by tacrine (tetrahydroaminoacridine) but the mechanism of this action of tacrine was not clarified (S. Tucek, V. Dolezal, J. Neurochem. 56 (1991) 1216). We have now investigated whether tacrine has an effect on the changes in the intracellular concentration of calcium ions ([Ca2+]i) induced by depolarization. Experiments were performed on the cholinergic SN56 neuronal cell line with Fura-2 fluorescence technique of calcium imaging. The depolarization by 71 mmol/l K+ evoked minimum increases of [Ca2+]i up to day 5 in culture. Then the response gradually increased and reached a plateau after 7 days in culture. A similar time course was observed for acetylcholinesterase activity. The effect of K+ ions was concentration-dependent and the concentration of 71 mmol/l K+ evoked maximum [Ca2+]i responses. The increases of [Ca2+]i did not occur in the absence of extracellular calcium. They were mediated by high voltage-activated calcium channels of the L-type and the N type. Nifedipine (2 micromol/l; L-type calcium channel blocker) and omega conotoxin GVIA (100 nmol/l; N-type calcium channel blocker) diminished the response to 71 mmol/l K+ by 53% and 39%, respectively, and their effects were additive (decrease to 8% of controls). Non-selective inorganic blocker of voltage activated calcium channels LaCl3 (0.1 mmol/l) decreased the response by 83%. Tacrine attenuated the [Ca2+]i response in a concentration-dependent manner. At a concentration of 10 micromol/l it inhibited the [Ca2+]i response by 55% and its inhibitory effect was additive with that of omega-conotoxin GVIA but not with that of nifedipine. An equimolar concentration of paraoxon, an irreversible inhibitor of cholinesterases, had no influence on [Ca2+]i response. Tacrine exhibited the same inhibitory effect when paraoxon was present. In conclusion, our data indicate that high-voltage-activated calcium channels of the L-type and the N-type are both present in the SN56 cells but that they are fully expressed only after 6-7 days in culture. Tacrine attenuates the influx of calcium by inhibiting the L-type calcium channels. This inhibitory effect is not a consequence of the anticholinesterase activity of tacrine. The finding that low micromolar concentrations of tacrine may interfere with calcium-dependent events is likely to be of importance for the evaluation of the therapeutic potential of the drug. PMID- 9374188 TI - Direct actions of anticholinesterases on the neuronal nicotinic acetylcholine receptor channels. AB - Recent studies have suggested that anticholinesterases including organophosphates and carbamates act directly on the nicotinic acetylcholine receptor (AChR) channel. We performed whole-cell and single-channel patch-clamp experiments to elucidate the mechanism of action of anticholinesterases on the nicotinic AChR in rat clonal phaeochromocytoma (PC12) cells. Neostigmine and carbaryl showed a biphasic effect; enhancement and suppression of carbachol-induced whole-cell currents. The currents induced by 100 microM carbachol was enhanced by the first co-application with 10 or 100 microM neostigmine, and the current was eventually suppressed below the control level during repeated co-applications. The decay phase of current was accelerated by neostigmine. Carbaryl at 0.1 microM greatly potentiated the carbachol-induced current, and at higher concentrations (0.3-3 microM), current was suppressed. In single-channel experiments, these compounds increased the short closures or gaps during channel opening without changing the single-channel conductance. Mean open time and burst duration were decreased in the presence of neostigmine and carbaryl. These results indicate that neostigmine and carbaryl directly block the nicotinic AChR channel. PMID- 9374190 TI - Effects of acute and repeated administration of N-methyl-D-aspartate (NMDA) into the ventral tegmental area: locomotor activating effects of NMDA and cocaine. AB - Repeated, intermittent administration of psychostimulants produces an enhancement of the subsequent behavioral effects of these drugs. This behavioral sensitization has been implicated in maintenance of and relapse to drug-taking. As a result, there has been great interest in elucidating the mechanisms underlying both the development and expression of sensitization. An accumulation of data from studies of stimulant-induced locomotor activity has implicated excitatory amino acids in the development of behavioral sensitization. In the present study, N-methyl-D-aspartate (NMDA) (0.6, 1.25 or 2.5 microg) infused bilaterally into the ventral tegmental area (VTA) produced dose-dependent locomotor activation. The locomotor activating effect of NMDA was increased following repeated NMDA administration (two exposures to intra-VTA NMDA), suggesting sensitization. However, repeated intra-VTA NMDA failed to sensitize rats to the locomotor activating effects of systemically administered cocaine (5.0, 10.0 or 20.0 mg/kg). These findings are consistent with the notion that repeated activation of NMDA receptors is sufficient for the development of behavioral sensitization to NMDA. Other neuroadaptations produced by repeated psychostimulant administration are required in order for the development of sensitization to the behavioral effects of those drugs. PMID- 9374191 TI - Neonatal transection of the infraorbital nerve increases the expression of proteins related to neuronal death in the principal sensory nucleus of the trigeminal nerve. AB - Neonatal lesion of the primary afferents in the infraorbital nerve causes the death of one-third of the neurons in the second-order target, the principal sensory nucleus of the trigeminal nerve (PSN). We examined the expression of two candidate 'death' proteins, p53 and the antigen recognized by the antibody ALZ 50, in the normal and deafferented PSN. In addition, the effect of neonatal transection of the infraorbital nerve (a major component of the trigeminal nerve) on protein expression was examined. The expression of c-fos in the developing PSN was also studied as an index of metabolic activity. Protein expression was measured using quantitative analyses of immunoblots and immunohistochemical preparations. The expression of p53- and ALZ-50-immunoreactivity in the normal PSN peaked during the first postnatal week. Transection of the infraorbital nerve directly affected the expression of p53 and the ALZ-50-positive antigen. The immunoblots showed that whereas p53 amounts were unaffected by the lesion, ALZ-50 expression was significantly upregulated in the ipsilateral PSN 2 h and 2 days postlesion. The density of p53- and ALZ-50-immunoreactive neurons was significantly higher in the ventral ipsilateral PSN (i.e., the target of the transected infraorbital nerve) than in the contralateral PSN. c-fos expression selectively and transiently rose in the ventral ipsilateral PSN within 2 h of the lesion. Thus, both p53 and the ALZ-50-positive antigen are involved in neuronal death. In light of data suggesting that ALZ-50 recognizes a phosphorylated form of p53, we conclude that neuronal death in the developing nervous system involves the post-translational modification of an existing protein, p53. The increase in ALZ-50 expression apparently occurs during a catabolic phase of neuronal death, as indicated by the increase in c-fos expression. PMID- 9374192 TI - Single potassium channels in neuropile glial cells of the leech central nervous system. AB - We performed patch-clamp experiments to identify distinct K+ channels underlying the high K+ conductance and K+ uptake mechanism of the neuropile glial cell membrane on the single-channel level. In the soma membrane four different types of K+ channels were characterized, which were found to be distributed in clusters. Since no other types of K+ channels were observed, these appear to be the complete repertoire of K+ channels expressed in the soma region of this cell type. The outward rectifying 42 pS K+ channel could markedly contribute to the high K+ conductance and the maintenance of the membrane potential, since it shows the highest open probability of all channels. The channel gating occurred in bursts and patch excision decreased the open probability. The outward rectifying 74 pS K+ channel was rarely active in the cell-attached configuration; however, patch excision enhanced its open probability considerably. This type of channel may be involved in neuron-glial crosstalk, since it is activated by both depolarizations and increases in the intracellular Ca2+ concentration, which are known to be induced by neurotransmitter release following the activation of neurons. The 40 pS and 83 pS K+ channels showed inward rectifying properties, suggesting their involvement in the regulation of the extracellular K+ content. The 40 pS K+ channel could only be observed in the inside-out configuration. The 83 pS channel was activated following patch excision. At membrane potentials more negative than -60 mV, flickering events indicated voltage-dependent gating. PMID- 9374193 TI - Denervation-induced sprouting of intact peripheral afferents into the cuneate nucleus of adult rats. AB - In adult monkeys with dorsal rhizotomies extending from the second cervical (C2) to the fifth thoracic (T5) vertebrae, cortex deprived of its normal inputs regained responsiveness to inputs conveyed by intact peripheral afferents from the face [T.P. Pons, P.E. Garraghty, A.K. Ommaya, J.H. Kaas, E. Taub, M. Mishkin, Massive reorganization of the primary somatosensory cortex after peripheral sensory deafferentation, Science 252 (1991) 1857-1860]. It has been suggested that the extent of this massive topographic reorganization may be due to the establishment of novel connections between intact afferents and neurons denervated after dorsal rhizotomy [P.E. Garraghty, D.P. Hanes, S.L. Florence, J.H. Kaas, Pattern of peripheral deafferentation predicts reorganizational limits in adult primate somatosensory cortex, Somatosens. Motor Res. 11 (1994) 109-117]. Using adult rats with comparably extensive dorsal rhizotomies, we employed anatomical tracing techniques to address this possibility. Subcutaneous hindpaw injections of horseradish peroxidase conjugated to either wheat germ agglutinin or cholera toxin subunit B revealed aberrant expansions of gracile projections into the cuneate and, in one case, external cuneate nucleus within three months of the deafferentation. It seems plausible that such modest sprouting of ascending projections at the level of the brainstem may form functional connections which, through divergence, ultimately drive a larger population of neurons in cortex. This new growth may well account for both the substantial cortical reorganization observed in the 'Silver Spring monkeys' [T.P. Pons, P.E. Garraghty, A.K. Ommaya, J.H. Kaas, E. Taub, M. Mishkin, Massive reorganization of the primary somatosensory cortex after peripheral sensory deafferentation, Science 252 (1991) 1857-1860] and the 'referred sensation' phenomena (see J.P. Donoghue, Plasticity of adult sensorimotor representations, Curr. Opin. Neurobiol., 5 (1995) 749-754 for review) reported to follow proximal limb amputations in humans. PMID- 9374194 TI - Quinine suppression of single facial taste fiber responses in the channel catfish. AB - Two groups of single facial taste fibers that were responsive to quinine hydrochloride (QHCl) and amino acids were identified in the channel catfish, Ictalurus punctatus. Group I fibers were significantly more excited by quinine hydrochloride (QHCl) than were group II fibers. QHCl (10(-3) M), as one component in a binary mixture, suppressed taste responses of group II fibers to 10(-4) M amino acids (other component) by 61%, but did not inhibit significantly the responses to L-alanine of group I fibers. QHCl (10(-2) M) suppressed the response to 10(-4) M L-alanine of group I fibers by 58% and group II fibers to 10(-4) M L alanine, L-arginine and L-proline by 89-100%. The suppression of amino acid responses of both groups of fibers by QHCl was reversible in subsequent testing of stimuli in the absence of QHCl. QHCl also suppressed the taste responses to other bitter stimuli [10(-3) M caffeine and 10(-2) M denatonium benzoate(DB)]; however, neither caffeine nor DB suppressed amino acid taste responses. Possible mechanisms for the suppressive effect of QHCl on taste nerve activity are discussed. PMID- 9374195 TI - Colocalization of NADPH-diaphorase and GABA-immunoreactivity in the olfactory and visual system of the locust. AB - Nitric oxide synthesizing neurons of the locust CNS have been identified by NADPH diaphorase staining. However, the conventional transmitters of these neurons are unknown. Here we use double labelling for NADPH-diaphorase and GABA immunofluorescence on sections of the brain to investigate a potential coexpression of both markers. The antennal lobe is innervated by a cluster of about 45-50 NADPH-diaphorase positive local interneurons which express GABA immunofluorescence. The mushroom bodies are a higher order olfactory center which receive an extrinsic innervation from GABA-immunoreactive and NADPH-diaphorase positive fiber systems. Each optic lobe contains about 4500 GABA-immunoreactive cell bodies. In the visual system, identifiable GABA-immunoreactive neurons arborize in the external plexiform layer of the lamina, in several strata of the medulla, and in the lobula complex. A survey of all NADPH-diaphorase positive cell groups detected a colocalization of GABA-immunoreactivity in a small subpopulation of somata along the anterior rim of the medulla. These cytochemical findings suggest that nitric oxide may be a characteristic cotransmitter of GABAergic circuits of the antennal lobe, while in mushroom bodies and the visual system the majority of nitric oxide and GABA releasing neurons are distinct populations. PMID- 9374196 TI - Release of adenosine and ATP in the brain of the freshwater turtle (Trachemys scripta) during long-term anoxia. AB - Extracellular adenosine and ATP levels were monitored by microdialysis in the striatum of the freshwater turtle Trachemys scripta during long-term N2 respiration. After an initial rise in extracellular adenosine, a second peak of longer duration and higher in intensity, followed. The frequencies of these adenosine cycles varied considerably between individual turtles, such that the shortest time between the peaks was 80 min and the longest was 300 min (mean 151 min). After about 60 min anoxia, there was also a slow increase in extracellular ATP, rising from a normoxic concentration of 1.21 +/- 0.12 to 7.58 +/- 3.70 nmol l(-1) at 240 min anoxia. The results suggest that adenosine may continue to have a protective function in the turtle brain during long-term anoxia and that extracellular ATP might not function as an excitatory neurotransmitter in the anoxic turtle brain. PMID- 9374197 TI - Physiological levels of beta-amyloid peptide stimulate protein kinase C in PC12 cells. AB - Alzheimer's beta-amyloid peptide (A beta) is normally present at nanomolar concentrations in body fluids and in the medium of cultured cells. In vitro experiments have shown that A beta has neurotrophic effects and can promote neuronal adhesion and elongation of axon-like processes. In an attempt to understand the molecular mechanisms underlying such effects, we have recently reported that nanomolar doses of A beta can stimulate protein tyrosine phosphorylation and activate phosphatidylinositol-3-kinase in neuronal cells. Here we show evidence that A beta can also activate protein kinase C, a serine/threonine kinase, in PC12 cells. First, using a serine-containing S6 peptide as an exogenous substrate, we found that nanomolar levels of A beta peptides 1-40 or 1-42 significantly stimulated an S6 phosphorylating kinase activity, whereas the A beta40-1 reverse sequence peptide had no effect. Down regulation of PKC by prolonged (18 h) treatment with 1 microM PMA prevented the A beta-induced S6 phosphorylation. Using a more specific PKC substrate, N-terminal acetylated peptide (4-14) from myelin basic protein, we then demonstrated that A beta indeed increased PKC activity and that this activity could be blocked by the PKC inhibitor, staurosporine. Finally, immunoblotting experiments showed that A beta induced translocation of PKCgamma from cytosol to membrane and also significantly reduced cytosolic PKCalpha levels. Taken together, these data suggest that physiological levels of A beta can regulate PKC activity. PMID- 9374198 TI - MK-801 potentiates antidystonic effects of clozapine but not of haloperidol in mutant dystonic hamsters. AB - The interaction of nigrostriatal dopamine and corticostriatal glutamate plays a critical role in motor output. Recent studies in mutant dystonic hamsters (dt[sz]), an animal model of idiopathic generalized dystonia, revealed antidystonic effects of both N-methyl-D-aspartate (NMDA) receptor antagonists, such as dizocilpine (MK-801), and of neuroleptics, such as haloperidol and clozapine. Whereas the neuroleptics reduced spontaneous locomotion at antidystonic effective doses, MK-801 caused hyperactivity in mutant hamsters. Therefore, the combination of neuroleptics and MK-801 may exhibit synergistic antidystonic effects, while the side effects may be counteracted. In order to prove this assumption, the neuroleptics haloperidol and clozapine were coadministered with MK-801 in dt(sz) hamsters in the present study. The antidystonic effects were potentiated by coadministration of MK-801 and clozapine, but not by the combination of MK-801 and haloperidol. The coadministration of MK-801 and clozapine did not cause severe side effects, such as catalepsy in dystonic hamsters. In contrast to the well-documented reverse of haloperidol-induced catalepsy by MK-801 in rats, in mutant hamsters, catalepsy was increased by coadministration of haloperidol and MK-801. This unexpected finding could be due to pathophysiological brain alterations in dt(sz) hamsters, because in non-dystonic control hamsters, combined treatment with MK-801 and haloperidol did not cause cataleptogenic effects. PMID- 9374199 TI - Lactation decreases mRNA levels of opioid peptides in the arcuate nucleus of the rat. AB - The state of lactation results in increased food intake to compensate for the increased energy expenditure to produce nutrients supplied to the offspring. In this study, Sprague-Dawley female rats lactating for 10-16 days, and rats 7 days post-lactation were implanted with osmotic minipumps infusing either naltrexone (NTX) (70 microg/h) or saline (0.9%) over a 48 h period. mRNA levels of pro dynorphin (proDYN), pro-opiomelanocortin (POMC) and pro-enkephalin (proENK) were measured in the arcuate nucleus (ARC) and whole pituitary of both groups. In both saline- and NTX-treated lactating subjects, food intake was higher than in post lactating subjects (P < 0.01). In post-lactating subjects, NTX decreased food intake by 27% during the infusion period (P < 0.05). There were no significant differences in body weight between the treatment groups; however, naltrexone decreased body weight gain in both lactating and post-lactating subjects. In both saline and NTX-treated lactating subjects, ARC mRNA levels of proDYN, POMC and proENK were significantly decreased compared with the saline or NTX-treated post lactating subjects (P < 0.01). NTX did not significantly influence gene expression of opioid peptides in the ARC in either the lactating or the post lactating subjects. Neither the lactation condition nor NTX administration significantly changed mRNA levels of proDYN, POMC or proENK in whole pituitary. Thus, as has been noted in energy-deprived rats, opioid peptide gene expression is decreased in the ARC of lactating rats, a period during which rats have increased energy requirements. PMID- 9374200 TI - The expression of a cloned Drosophila octopamine/tyramine receptor in Xenopus oocytes. AB - The expression of a cloned Drosophila octopamine/tyramine receptor (OctyR99AB) is described in Xenopus oocytes. Agonist stimulation of OctyR99AB receptors increased intracellular Ca2+ levels monitored as changes in the endogenous inward Ca2+-dependent chloride current. The receptor is preferentially sensitive to biogenic amines with a single hydroxyl on the aromatic ring. The G-protein, Galphai, appears to be involved in the coupling of the receptor to the production of intracellular calcium signals, since the effect is pertussis-toxin sensitive and is blocked or substantially reduced in antisense knockout experiments using oligonucleotides directed against Galphai but not by those directed against Galphao, Galphaq and Galpha11. The increase in intracellular calcium levels induced by activation of the OctyR99AB receptor can potentiate the ability of activation of a co-expressed beta2-adrenergic receptor to increase oocyte cyclic AMP levels. A comparison of the pharmacological coupling of OctyR99AB to different second messenger systems when expressed in Xenopus oocytes with previous studies on the expression of the receptor in a Chinese hamster ovary cell line suggests that the property of agonist-specific coupling of the receptor to different second messenger systems may be cell-specific, depending upon the G protein environment of any particular cell type. PMID- 9374202 TI - Stability of brain content of magnesium in experimental hypomagnesemia. AB - Magnesium is important in cerebral function. If there is a deficiency and neurological symptoms accrue, we hypothesised that Mg2+ deficiency causes neurological symptoms by decreasing the level of Mg2+ in cerebral tissue. The content of magnesium was determined in 12 brain structures in magnesium-deficient rats. Experiments were carried out for 40 days in two groups of Wistar male rats made magnesium-deficient (MD) by a well-controlled diet (50 mg of Mg2+/kg of food), and a control group (CG) rats fed normal diet (1 g of Mg2+/kg of food). At the end of the 40 days, the clinical signs of hypomagnesemia were sought in the MD rats and Mg2+ concentration levels were measured in the blood and brain. The results showed variable distribution of Mg2+ in the different brain structures, both in CG and MD rats; in the MD rats there is an important stability of global Mg2+ content of the brain. Although the global values for Mg2+ in the brain did not decline in MD rats, there was a significant decrease in Mg2+ in the brainstem. We conclude that the brain is able to maintain a stable concentration of Mg2+ during chronic hypomagnesemia, but its topographic variations could account for some of neurological signs accompanying this condition. PMID- 9374201 TI - Protective effect of a prostaglandin I2 analog, TEI-7165, on ischemic neuronal damage in gerbils. AB - TTC-909 (Clinprost), a chemically stable PGI2 analog, isocarbacyclin methyl ester (TEI-9090 or Clinprost) incorporated in lipid microspheres, when administered intravenously after brain ischemia, prevents ischemic neuronal damage possibly by modulating cerebral blood flow and platelet aggregation. However, the possibility exists that TEI-7165, which is the free acid form and a central metabolite of TEI 9090, has direct neurotrophic action in vivo, since TEI-7165 has been shown to block neuronal voltage-dependent Ca2+ channels in vitro, and a novel prostacyclin receptor showing high affinity with TEI-7165 has been detected in a variety of brain regions including the hippocampus. In the present study, we infused TEI 7165 for 7 days into the lateral ventricle of gerbils starting 2 h before or just after 3-min forebrain ischemia. TEI-7165 infusion prevented significantly the ischemia-induced shortening of response latency time as revealed by a step-down passive avoidance task. Subsequent light and electron microscopic examinations showed that pyramidal neurons in the hippocampal CA1 region, as well as synapses within the strata moleculare, radiatum and oriens of the region, were significantly more numerous in gerbils infused with TEI-7165 than in those receiving vehicle infusion. TEI-7165 infusion did not affect hippocampal blood flow or temperature. These findings, together with the previously depicted accumulation of centrally administered [3H]TEI-7165 around hippocampal neurons, suggest that TEI-7165 has a direct neuroprotective action in brain ischemia. PMID- 9374203 TI - Proline-induced inhibition of glutamate release in hippocampal area CA1. AB - Concentrations of proline typical of human CSF have been shown to potentiate transmission at Schaffer collateral-commissural synapses on CA1 pyramidal cells of the rat hippocampus. This study tested the hypothesis that proline enhances excitatory synaptic transmission by increasing glutamate release. Two concentrations of proline were used: a concentration typical of normal human CSF (3 microM) and a concentration typical of CSF in persons with the genetic disorder hyperprolinemia type II (30 microM). Continuous exposure of hippocampal slices to either concentration of proline potentiated Schaffer collateral commissural synaptic transmission. Proline shifted the plot of field EPSP slope against fiber volley amplitude upward. Contrary to the original hypothesis, neither concentration of proline reduced paired-pulse facilitation; 30 microM proline enhanced paired-pulse facilitation, whereas 3 microM proline had no effect. In line with its enhancement of paired-pulse facilitation, 30 microM proline reduced both the K+-evoked release of glutamate and aspartate from CA1 slices and the release of glutamate and aspartate from CA1 synaptosomes evoked by 4-aminopyridine. These results suggest that the proline-induced potentiation of Schaffer collateral-commissural synaptic transmission probably involves a postsynaptic, rather than a presynaptic, mechanism. Concentrations of proline normally found in human CSF little affect glutamate release. However, proline induced inhibition of glutamate release may contribute to the neuropsychiatric disorders associated with hyperprolinemia type II. PMID- 9374204 TI - Differential toxic effects of methamphetamine (METH) and methylenedioxymethamphetamine (MDMA) in multidrug-resistant (mdr1a) knockout mice. AB - The toxic effects of methamphetamine (METH) (2.5, 5.0 and 10.0 mg/kg) and methylenedioxymethamphetamine (MDMA) (5.0, 10.0 and 20.0 mg/kg) on dopaminergic systems were assessed in the striatum and of the nucleus accumbens in mdr1a wild type and knockout mice. METH caused significant dose-dependent decreases of dopamine (DA) and DA transporters (DAT) in the striatum and the nucleus accumbens (NAc) of both wild-type and knockout mice. The lowest doses of METH (2.5 mg/kg) caused only small changes in the wild-type, but marked. decreases in the mdr1a knockout mice. The two higher doses (5 mg/kg and 10 mg/kg) caused similar changes in both strains of mice. In contrast to METH, MDMA caused greater percentage decreases in DAT in the wild-type mice. For example, the lowest dose (5 mg/kg) caused significant decreases in DAT in the NAc of wild-type but not of mdr1a knockout mice. The highest dose (20 mg/kg) caused similar changes in both the strains. These results suggest that METH and MDMA interact differentially with P glycoproteins. These observations document, for the first time, a role for these proteins in the entry of METH and MDMA into the brain via the blood-brain barrier, with P-glycoprotein possibly facilitating the entry of MDMA but interfering with that of METH into the brain. PMID- 9374205 TI - Role of nucleus retroambigualis in respiratory reflexes evoked by superior laryngeal and vestibular nerve afferents and in emesis. AB - An ascending projection from the medullary nucleus retroambigualis (NRA) has recently been described as important for the control of the upper airway during vocalization. We evaluated the importance of this projection in other behaviors by making localized injections of the neurotoxin kainic acid in the NRA in decerebrate cats, most of which were paralyzed and artificially ventilated. In contrast to its importance for vocalization, the NRA is not essential for activation of upper airway musculature during respiration, swallowing, vomiting, or reflexes elicited by superior laryngeal or vestibular nerve afferents. However, kainic acid injections in the NRA and adjacent reticular formation prolonged the inhibitory phrenic motoneuronal response to superior laryngeal nerve stimulation and abolished or reduced abdominal motoneuronal responses during respiration, vomiting, and superior laryngeal nerve stimulation. Thus, of the behaviors we investigated, the importance of the ascending projection from the NRA appears to be limited to vocalization, while descending projections from the NRA region are important in a number of behaviors. PMID- 9374206 TI - The corticosteroid synthesis inhibitors metyrapone and aminoglutethimide impair long-term memory for a passive avoidance task in day-old chicks. AB - Long-term memory for a passive avoidance task in day-old chicks has proved to depend upon an action of the adrenal steroid corticosterone through specific receptors in a brain region, the intermediate medial hyperstriatum ventrale (IMHV), involved in learning the task. In this study, we questioned whether pretraining peripheral administration of drugs described to inhibit either basal levels of corticosterone - aminoglutethimide - or treatment-induced stimulated corticosterone secretion - metyrapone - might interfere with retention for the task at 24 h post-training. The results showed a dose-dependent effect of the inhibitors, with the highest doses tested for both drugs (10 and 50 mg/kg for metyrapone, and 50 mg/kg for aminoglutethimide) being amnestic for the task. Additional experiments, in which we studied possible effects of the inhibitors on concomitant aspects of learning (i.e., reactivity to novelty, and pecking pattern), show that the drugs did not affect general behavioural reactivity. The present results thus support the idea that training-induced corticosterone release plays a key role in the neurobiological processes that determine the establishment of a persistent memory for the aversively motivated avoidance response. In addition, they point to corticosteroid inhibitor drugs as potential tools for the study of the interactions between steroid hormones and cognition enhancing compounds in this learning task. PMID- 9374207 TI - Changes in pain perception and pain-related somatosensory evoked potentials in humans produced by exposure to oscillating magnetic fields. AB - Nociception has been reported to be influenced by exposure to magnetic fields (MFs). The aim of this study was to investigate the effects of 2 h exposure to weak, oscillating MFs on pain perception thresholds and on pain-related somatosensory evoked potentials (SEPs). In 11 healthy volunteers, pain perception thresholds and pain-related SEPs were assessed by intracutaneous electrical stimulation. After sham treatment, pain thresholds significantly increased, whereas after MFs a slight non-significant decrease in thresholds was found. After both treatments pain-related SEP amplitude was reduced, but this decrease was more evident and statistically significant only after MF exposure. The increase found in thresholds after sham exposure may be due to stress-induced analgesia (SIA) and the contrasting behaviour recorded after MF exposure might indicate a suppression of SIA. The significant reduction in pain-related SEP amplitude observed after MF exposure provides the first evidence that human SEPs are influenced by MFs. PMID- 9374208 TI - Changes of cytochrome oxidase activity in rat suprachiasmatic nucleus. AB - This paper evaluates the changes of cytochrome oxidase (CO) activity that take place in the suprachiasmatic nucleus (SCN) during the light-dark cycle. CO is a mitochondrial energy-generating enzyme used as a marker of neural oxidative metabolism. We measured CO activity using quantitative histochemistry calibrated with brain tissue standards and a computerized analysis image system. The results indicate that the CO enzyme activity changes on the basis of a circadian pattern, with the higher levels during the light phase (P < 0.0001). These changes are detected over a period of hours, in accordance with other studies on the possible short-term regulation of CO activity in the nervous system. It is, therefore, possible to apply this methodology to the study of the SCN and other brain areas which show functional rhythmicity. PMID- 9374209 TI - Transcription of the mouse mu-opioid receptor gene is regulated by two promoters. AB - Two transcription initiation sites have been identified in the mouse mu-opioid receptor (MOR) gene at approximately -793 and -268 upstream of the translation start site. To test if the MOR gene contains two functional promoters, chimeric constructs of mouse MOR deletion fragments, fused to a luciferase reporter gene, were transiently transfected into the neuroblastoma cell line SK-N-SH, a MOR expressing cell line, and two MOR-non-expressing cell lines. Results from transient transfection assays confirmed the existence of two functional independent promoters in the mouse MOR gene, and also revealed that the region from -1337 to -93 does not contain all the elements necessary to confer tissue specific expression of the MOR gene. PMID- 9374210 TI - Axonal cytoskeletal pathology in aged and diabetic human sympathetic autonomic ganglia. AB - Prevertebral sympathetic ganglia develop markedly enlarged argyrophilic neurites as a function of age, gender and diabetes. Immunolocalization studies demonstrate their preferential labeling with antisera to highly phosphorylated 200 kDa neurofilament (NF-H) epitopes, NPY, peripherin and synapsin I, but not to hypophosphorylated NF-M and NF-H or MAP-2. The immunophenotype of dystrophic neurites in conjunction with the results of histochemical and ultrastructural studies are consistent with the terminal axonal and/or synaptic origin of neuritic dystrophy in the sympathetic ganglia of aged and diabetic human subjects. PMID- 9374211 TI - Neurons express proteins of the classical complement pathway in Alzheimer disease. AB - Occurrence of the classical pathway complement proteins C1q, C1r, C1s, C2, C3, C4, C5, C6, C7, C8 and C9 was studied in human hippocampus and temporal cortex by immunohistochemistry and Western blotting. In Alzheimer disease (AD) cases, positive staining for all of these proteins was observed in pyramidal neurons and senile plaques. In control cases, weaker pyramidal neuron staining was observed except for C1q and C1s which were not detected. On Western blots of AD hippocampal extracts, bands corresponding to those detected in normal serum were found for each of the complement proteins. Comparable bands were also detected in normal hippocampal extracts with the exception of C1s which was not observed. The intensity of the bands was generally stronger in AD than in normal extracts, but, in the latter, there was considerable variability between cases and between bands in a single case. These data suggest that pyramidal neurons may be a source of the complement components known to be associated with Alzheimer lesions. PMID- 9374212 TI - Neuronal expression of mRNAs for complement proteins of the classical pathway in Alzheimer brain. AB - To determine possible sources of complement proteins in the brain, we investigated by in situ hybridization expression of the mRNAs of C1q, C2, C3, C4, C5, C6, C7, C8 and C9 in postmortem Alzheimer disease (AD) and control brain tissue. We found detectable hybridization for all these components in the temporal cortex and hippocampus, with significantly higher levels being found in AD tissue. Hybridization signals were strongest over pyramidal neurons. Low or absent hybridization was seen in the visual cortex or cerebellum. These results suggest that the activated complement components found in association with AD lesions may be, in part, derived from neurons. PMID- 9374213 TI - Acid-sensing by carotid body is inhibited by blockers of voltage-sensitive Ca2+ channels. AB - The membrane potential hypothesis that the responses to hypercapnia of carotid chemosensory activity is mediated by voltage-gated Ca2+ channels was investigated by measuring directly the chemosensory output from rat and cat carotid bodies, perfused and superfused in vitro. We found that the inorganic and organic blockers of voltage-gated Ca2+ channels suppressed the hypercapnic responses, thereby supporting the membrane potential hypothesis. PMID- 9374214 TI - The genetic basis of head and neck carcinoma. AB - Research over the past few years has pointed to a genetic basis for numerous cancers. Efforts in this regard are ongoing in squamous carcinoma of the head and neck. Today surgeons and residents in training need to stay up to date on molecular biology and the genetic sequences that are necessary to form a malignancy. In addition, these changes offer diagnosticians and therapists novel ways both to diagnose and treat malignancies. An evolution in molecular genetics, tumor virology, and tumor biology has led to our understanding of how malignancies arise. There are two pathways of cancer production: the activation of an oncogene or the mutation of a tumor suppressor gene. This review discusses the interaction of these genetic changes in the development of squamous carcinoma of the head and neck, their relationship to tobacco and alcohol use, as well as methods to detect the presence of malignancy and novel techniques that may be used to treat malignancies in the future. PMID- 9374215 TI - Hayes Martin Lecture. Our AMES is true: how an old concept still hits the mark: or, risk group assignment points the arrow to rational therapy selection in differentiated thyroid cancer. PMID- 9374216 TI - Percutaneous dilational tracheostomy for airway control. AB - BACKGROUND: Endoscopic percutaneous dilational tracheostomy (PDT) is a good alternative to obtain safe and secure long-term airway control, and is associated with minimal morbidity and mortality. STUDY DESIGN: During a 14-month period, we prospectively studied 35 intensive care unit (ICU) trauma patients who underwent early PDT for the sole purpose of obtaining long-term airway control. All patients were determined to need a tracheostomy owing to extubation inability, need to maintain a patent airway, or need for continuous airway access for management of secretions. RESULTS: All patients had sustained multiple injuries with an average Injury Severity Score (ISS) of 29. The time from ICU admission to placement of the PDT was 8 +/- 5 days. The mean Glasgow Coma Scale at the time of the PDT was 10 (range 4 to 15), and 11 patients (31%) had an intracranial pressure device in place. The procedure was completed with bronchoscopic guidance in 33 patients, and in 2 it was converted to surgical tracheostomy (ST). There were no significant complications associated with the placement of the PDT. Two deaths were documented, neither related to the PDT placement. Compared with standard ST, charges were reduced by $1,750. CONCLUSIONS: Bedside endoscopic PDT for selected critically ill trauma patients is justified as a safe and effective alternative to ST. The low incidence of complications in PDT suggests that it can be done safely at bedside in the ICU. PMID- 9374217 TI - Differentiated thyroid cancer presenting initially with distant metastasis. AB - BACKGROUND: The initial presentation of distant metastases in patients with differentiated thyroid cancer is a rare event. Interestingly, if managed appropriately, the long-term survival in this group of patients is approximately 43%. We intend to review our experience of patients presenting initially with distant metastatic disease in a large series of differentiated thyroid cancer patients. METHODS: In the entire series of 1,038 consecutive patients treated at Memorial Sloan-Kettering Cancer Center from 1930 to 1985, 44 patients presented initially with distant metastases (4%). There were 22 male and 22 female patients ranging in age from 7 to 75 years with a mean age of 51 years. Patients were analyzed for their prognostic factors, and the survival curves were drawn by the Kaplan-Meier method. Univariate and multivariate analyses were performed by the Cox regression model. RESULTS: There were 19 patients presenting with distant metastases in 810 patients presenting with papillary thyroid cancer (2.3%). The incidence was high in patients with follicular thyroid cancer (11%). It is interesting to note that the highest incidence of presentation with distant metastatic disease was in patients above the age of 45 and with follicular thyroid carcinoma. The long-term survival in this group is 43% compared with 86% in patients presenting without distant metastasis (P < 0.001). There was no statistical difference in survival of patients below or above the age of 45. CONCLUSION: Even though the presence of distant metastasis at the time of initial presentation in other cancers is considered to be of grave prognosis, for patients with differentiated thyroid cancer, the long-term survival is still 43%. The incidence of distant metastasis is highest in patients with follicular thyroid cancer. Appropriate initial evaluation and treatment will lead to satisfactory long-term survival. PMID- 9374218 TI - Quality control in planning and technique of radiotherapy with cobalt-60 for T1 glottic cancer increase local control and organ preservation. AB - BACKGROUND: In order to evaluate whether individualized technique and dosimetry of radiotherapy increase local control, organ preservation, and survival of patients with T1 glottic cancer, we reviewed 76 cases treated from 1979 to 1993. METHODS: Group A included 32 patients treated from 1979 to 1989 with different techniques, based on clinical aspects. Group B included 44 patients treated from 1990 to 1993 with individualized technique according to tumor extension and patient's anatomy. RESULTS: Five-year local control with radiotherapy alone was achieved in 53% of group A versus 91% of group B (P > 0.005). Survival was similar in both groups with rescue surgery (90% versus 96%). Five-year survival with larynx preservation was 65% in group A versus 88% in group B (P = 0.02). Most recurrences (78%) appeared within 24 months of follow-up. CONCLUSION: Adequate staging, individualized technique, computing planning using simulation and use of immobilization devices during cobalt-60 radiotherapy significantly increase local control and organ preservation in T1 glottic cancer. PMID- 9374219 TI - The effect of cryopreservation on parathyroid cell viability and function. AB - BACKGROUND: Higher failure rates have been reported with cryopreserved versus fresh parathyroid autografts. The purpose of this study was to investigate the effects of cryopreservation on live cell yield and to determine if freezing tissue as dispersed cells could improve functional outcome. METHODS: Live cell yield and cytosolic calcium (Ca[i]) and parathyroid hormone (PTH) responses to extracellular calcium were investigated prior to and after 1 to 52 weeks of cryopreservation of bovine parathyroid tissue fragments (group I) or dispersed cells (group II). Tissue was frozen using a liquid nitrogen freezer. RESULTS: A 70% to 90% reduction in live cell yield was observed in groups I and II (P > 0.05), and this was unrelated to duration of cryopreservation. Cytosolic calcium and PTH responses to extracellular calcium in group I were similar to controls. In group II, transient Ca(i) responses were abolished, steady-state Ca(i) responses were blunted (P < 0.05), and PTH secretion was higher than in controls (P < 0.05). CONCLUSIONS: Cryopreservation decreases live cell yield independent of length of storage. Freezing dispersed parathyroid cells produces functional abnormalities in Ca(i) and PTH regulation. Maximizing the amount of tissue for cryopreservation may improve the yield of live cells and the success rate of cryopreserved parathyroid autografts. PMID- 9374220 TI - Extended neck dissection. AB - BACKGROUND: This study defines the clinical settings in which extended radical neck dissection (ERND) was performed and determines its impact on control of disease in the neck and on survival. METHODS: We reviewed the records of 106 patients undergoing ERND between 1984 and 1993. Most (76) had metastatic squamous cell carcinoma (SCC) that had extended to extranodal structures in the upper neck. RESULTS: Five-year disease-free survival was 39%, and disease was controlled in the neck in 72 patients (68%) with a median follow-up of 5.5 years. A trend toward better survival was seen in patients with SCC (47% at 5 years), compared with those with other histologies (24% at 5 years; P <0.12). Patients with levels I, II, or III involved had better survival (46% at 5 years) than those with level IV, V, or multiple levels involved (14% at 5 years; P <0.0088). Finally, when prior radiation therapy precluded additional irradiation of the neck, survival was only 22% at 5 years, compared with 47% for those who received postoperative radiation (P <0.017). CONCLUSIONS: Although advanced neck disease invading adjacent structures remains an ominous sign, neck control and 5-year survival were achieved in nearly one half of these patients when multimodality therapy was possible. PMID- 9374221 TI - Near-total laryngectomy for treatment of advanced laryngeal cancer. AB - BACKGROUND: In order to assess whether near-total laryngectomy (NTL) could successfully reach the cure and preserve the voice in advanced laryngeal cancer, we studied 28 patients with T3/T4 squamous cell carcinoma of the larynx treated with NTL in our institution. METHODS: A retrospective analysis has been carried out from 1990 through 1994. We classified 24 patients as Stage III and 4 patients as Stage IV. All patients had lateral neck dissection. Survival was analyzed under the Kaplan-Meier method. RESULTS: Twenty-six patients achieved voice preservation. Two patients in the bilateral neck dissection group had a metastatic lymph node on the opposite side. No patient had local recurrence. Three patients died of the disease, and 1 patient was salvaged with neck dissection. Three-year disease-free survival was 85%. CONCLUSION: This technique is useful in the treatment of selected cases of advanced laryngeal cancer and achieves local control of the lesion in all cases. The survival is comparable with that of patients submitted to total laryngectomy, regarding the extent of lesion. Voice preservation can be achieved in most cases. PMID- 9374222 TI - Histologic changes of intraoral free skin flaps. AB - BACKGROUND: It was the purpose of this study to assess the histologic skin changes of free tissue transfers used to reconstruct intraoral defects. METHODS: Patients who were at least 12 months after intraoral free tissue reconstruction were selected for study. A 3-mm punch biopsy of the intraoral portion of the flap was performed and submitted for routine histologic analysis and periodic acid Schiff (PAS) staining. The adjacent native oral mucosa was also biopsied and served as control. RESULTS: Eight patients (42 to 71 years old) were studied. A variety of skin flaps were employed and included free rectus abdominis (4), radial forearm (2), scapula (1), and osteocutaneous fibula flaps (1). Histologic examination demonstrated that all specimens maintained normal skin architecture and maturation. Adnexal structures were demonstrated in all but one. Acute inflammation in conjunction with diffuse parakeratosis and spongiosis were seen with 4 cases. Fungal forms consistent with Candida species were identified in the stratum corneum by PAS stain in these 4 cases. CONCLUSION: The histologic integrity of skin appears to be maintained in cutaneous free flaps placed intraorally. Previous studies have noted an inflammatory infiltrate in the epithelial tissues of intraorally placed flaps, yet have not commented on the significance of this finding even when it was noted in a chronic setting. Our study is the first to correlate these changes with the presence of fungi. The effect of the acute inflammation and associated fungal forms may suggest the need for chronic therapy and merits further study. PMID- 9374223 TI - Distant metastasis in adenoid cystic carcinoma of salivary origin. AB - BACKGROUND: Adenoid cystic carcinoma (ACC) is an aggressive, often indolent tumor, with a high incidence of distant metastasis (DM). Relatively little has been written about the factors that influence distant spread and subsequent survival because it is uncommon and more than a decade of observation may be required to appreciate the prolonged clinical course in some patients. METHODS: We have retrospectively studied 196 determinate patients who received definitive treatment in our hospital between 1939 and 1986 for ACC in all salivary sites. Inclusion criteria were no prior treatment elsewhere other than excisional biopsy and eligibility for follow-up of at least 10 years. Variables assessed for their impact on distant metastasis included age, gender, site, size, node status, stage, grade, and locoregional treatment failure. RESULTS: Treatment failure occurred in a total of 122 of 196 determinate patients (62%), 74 of whom had DM (38%). This was usually associated with locoregional recurrence (51 patients), but DM was the only indication of failure in 23 whose primary tumor was controlled. Of the 74 patients with known DM, the lung was recorded as the only involved site in 50 patients, lung was involved in addition to other sites in 17, bone metastases alone occured in 5, and the remaining 2 developed disseminated disease. Disease-free intervals varied from 1 month to 19 years (median 36 months) and exceeded 10 years in 9 of 113 patients (8%) with adequate information about treatment failure. Survival with DM was less than 3 years in 54%, but more than 10 yrs in 10% (maximum 16 years). The only significant factors influencing survival were the size of the primary tumor (P <0.0000), local or neck recurrence (P = 0.0006), and the presence of nodal involvement (P = 0.02). CONCLUSIONS: The high incidence of DM with locoregional failure confirms the importance of aggressive initial surgery, combined with irradiation, for high-stage tumors or involved surgical margins. Large tumor size and lymph node involvement, rather than microscopic appearance, were predictive of DM. Considering that lung metastases are usually multiple, and prolonged survival without treatment is not unusual, resection of pulmonary metastases may be hard to justify in ACC patients based on the limited experience thus far reported. Chemotherapy for metastatic ACC is probably best withheld until symptoms appear. PMID- 9374224 TI - Surgical treatment of lung metastases of head and neck tumors. AB - BACKGROUND: Head and neck tumors often spread to the lungs, with a variety of presentations. The ideal treatment for those patients is still controversial. Resection of lung metastases was shown to significantly influence overall survival of patients. OBJECTIVE: To evaluate results of surgical resection of lung nodules in patients with head and neck primary tumors. METHODS: A retrospective analysis was made of 53 patients with head and neck tumors and lung nodules (no other metastases detected in other organs) admitted to our department. They were separated into two groups: OPER (thoracotomy, n = 26), and NOTOPER (no thoracotomies, n = 27). Overall survival was compared (Kaplan-Meier, log-rank) between groups. RESULTS: Overall median survival of all patients was 10 months, of OPER 20 months, and of NOTOPER 6 months (P <0.0001). Complete resection (n = 19) of lung metastases was associated with the greatest survival rate (median 23 months). Patients submitted to incomplete resection (n = 7) had a median survival of 16 months, compared with 7 months for patients who received only chemotherapy (n = 7) and 4 months for patients (n = 20) with no treatment (P <0.0001). CONCLUSION: Resection of lung metastases offers a significant survival benefit for patients with head and neck primary tumors, when compared with the current chemotherapeutic regimens. It should be considered for all patients clinically fit and who present with no extrapulmonary disease. PMID- 9374225 TI - Long-term evaluation of bone mass in free fibula flap mandible reconstruction. AB - BACKGROUND: Vascularized fibula transfer has become a preferred method of mandibular restoration after oncologic surgical ablation. In order to elucidate the long-term effect on fibular mass after mandibular reconstruction, change in fibular height was utilized as an indirect measure of change in bone mass over time. Other potentially influential factors in long-term bone mass preservation were evaluated; these included site of reconstruction (central, body, ramus), patient age, length of follow-up, adjuvant radiotherapy, and the delayed placement of osseointegrated dental implants. METHODS: A retrospective analysis of patients undergoing free fibula mandible reconstruction for oncologic surgical defects between 1987 and 1993 was performed. Postoperative panorex examinations were used to evaluate fibular height and bony union after osteotomy. Fixation hardware was used as a reference to eliminate magnification as a possible source of error in measurement. Only patients with at least 24 months follow-up were included in this study. RESULTS: There were 27 patients (15 males and 12 females) with a mean age of 43 years (range 14 to 65) included in this study. Mandibular defects were anterior (16) and lateral (11). There were between two and five segmental osteotomies per patient (excluding the ends of the graft). Thirty percent of patients had delayed placement of osseointegrated dental implants. Initial panorex examinations were taken between 1 and 9 months (mean 2) postoperatively. Follow-up panorex examinations were taken 24 to 104 months (mean 54) postoperatively. The bony union rate after osteotomy was 93%. Comparative measurements of fibular height revealed that central segments underwent a mean decrease in height by 4% (range 0% to 22%); body segments decreased in height by 7% (range 0% to 33%); ramus segments decreased in height by 5% (range 0% to 15%). In each anatomic segment, fibular height varied by 10% or less when compared with respect to patient age, length of follow-up, adjuvant radiation therapy, and the presence of osseointegrated dental implants. CONCLUSIONS: We conclude that the retention of fibula height seen in this study indicates that fibula bone mass is preserved after free flap mandible reconstruction. Furthermore, these findings are not affected by the site of reconstruction, patient age, length of follow-up, adjuvant radiation therapy, or presence of osseointegrated dental implants. This study further supports the efficacy of vascularized fibula grafts for mandible reconstruction. PMID- 9374226 TI - Coexpression of interleukin-8 receptors in head and neck squamous cell carcinoma. AB - BACKGROUND: Interleukin 8 (IL-8) is an important cytokine involved in tumor growth and angiogenesis in a variety of malignancies. We hypothesize that IL-8 plays an important role in the cellular proliferation and angiogenesis seen in head and neck squamous cell carcinoma (HNSCC) and set out to identify its receptors, IL-8RA and IL-8RB. METHODS: Immunohistochemical analysis was performed on specimens from 38 HNSCC patients with stage I to IV disease and control tissues. RESULTS: All of cancer specimens demonstrated positive staining for IL 8RA. The IL-8RA staining of microvessel endothelial cells was seen in 51%. The IL 8RB pattern was similar to the IL-8RA pattern in that 97% of cancer sections demonstrated positive cancer cell staining, and 74% of the specimens demonstrated positive staining for microvessel endothelial cells. CONCLUSION: Our studies demonstrate that IL-8 receptors are expressed by cancer cells and microvessel endothelial cells in HNSCC, suggesting that IL-8 may act in an autocrine/paracrine fashion to stimulate cellular proliferation and angiogenesis. PMID- 9374227 TI - Vascular endothelial growth factor expression in head and neck squamous cell carcinoma. AB - BACKGROUND: Angiogenesis is an essential process required for growth and metastasis in cancer. In breast, gastric, and prostate cancer, vascular endothelial growth factor (VEGF) has been implicated in angiogenesis; however, little is known about VEGF in HNSCC. In this study, we hypothesize that VEGF is present in elevated levels in HNSCC and may therefore play a role in promoting angiogenesis. METHODS: We obtained tumor tissue from 63 HNSCC patients undergoing primary resection. All tissue samples were analyzed by immunohistochemistry (IHC) techniques for the presence and localization of VEGF; however, only 36 had sufficient amounts of tissue for quantitative analysis of VEGF by ELISA. Nine control specimens taken from patients undergoing uvulopalatopharyngoplasty were also analyzed. RESULTS: In all 63 of our patient samples we found VEGF to be present and localized to the cancer cells and endothelial cells. The poorly differentiated cancer cells stained more intensely in comparison with the well differentiated ones. There was a 20-fold increase in the patient levels when compared with controls levels (P > or =0.05). Analysis by enzyme-linked immunosorbent assay revealed elevated mean levels of VEGF (241 +/- 326 pg/mg total protein [TP]) with a range of 2 to 1484 pg/mg TP. The control specimens had mean levels of 13 +/- 11 pg/mg TP and a range of 1 to 78 pg/mg TP. Patients who exhibited higher levels of VEGF tended to have a higher rate of disease recurrence (P < or =0.048) and shorter disease-free interval (P < or =0.05). CONCLUSIONS: The expression of VEGF in elevated levels in the HNSCC tumor microenvironment appears to be associated with more aggressive disease. Based on our results, VEGF may be an important angiogenic factor associated with cancer cells and endothelial cells in HNSCC. Further studies are needed to better define the role of VEGF in HNSCC and its role as a potential target for therapeutic intervention. PMID- 9374229 TI - Tumor angiogenesis as a prognostic factor in laryngeal cancer. AB - BACKGROUND: Lymph node metastasis is the single greatest predictor of recurrence in laryngeal cancer. Prognostic factors are needed to target patients who may benefit from adjuvant therapy. Tumor angiogenesis correlates with metastasis in breast, bladder, and oral cavity cancer and may have prognostic value in other tumors. METHODS: In order to examine the relationship of tumor angiogenesis to recurrence, 51 patients with squamous cell carcinoma of the larynx were reviewed. In a blinded design, previously sectioned slides were chosen for advanced tumor and highest vessel concentration. Samples were cut and immunocytochemically stained for CD-31 (an endothelial marker). A computer image analyzer quantitated the percent area of staining. Variables were statistically examined against recurrence. RESULTS: Patients were stratified by percent tumor staining. Nodal involvement was seen in 9 (36%) patients with tumor staining < or = 20% and in 20 (77%) with tumor staining > 20% (P = 0.003). Patients with < or = 20% staining and without metastasis had a 13% rate of recurrence whereas patients with > 20% staining and without metastasis had a 67% rate of recurrence (P = 0.025). CONCLUSIONS: Though nodal status was suggestive of predictability, only angiogenesis is a statistically significant predictor of recurrence in node negative patients (P = 0.025). Angiogenesis shows strong correlation with regional recurrence and may be used as an independent prognostic indicator to determine clinically node negative patients who may be at higher risk for metastasis and require adjuvant therapy. PMID- 9374228 TI - Preoperative chemoradiation coupled with aggressive resection as needed ensures near total control in advanced head and neck cancer. AB - BACKGROUND: Preoperative chemotherapy or chemoradiation protocols are generally associated with high clinical response rates, but limited pathologic responses for large primary tumors. We have initiated a prospective phase II study of weekly paclitaxel 60 mg/M2, and carboplatin (AUC of 1) plus concurrent fractionated external beam radiation (45 Gy) followed by organ-preserving (or function restorative) surgery when applicable to maximize local-regional tumor control. PATIENTS AND METHODS: Operable patients staged by triple endoscopy received a percutaneous endoscopic gastrostomy and vigorous dental and nutritional support during therapy. Weekly paclitaxel 60 mg/M2, carboplatin (AUC of 1), and radiation 45 Gy were given with rebiopsy of the primary site at 5 weeks. Patients with positive biopsy had definitive surgery in 4 to 5 weeks. Patients with negative biopsy-results received 3 additional weeks of radiation, to a total dose of 72 Gy plus carboplatin and paclitaxel. RESULTS: The 35 patients were 29 men and 6 women, aged 40 to 71 years, with stage III (12) or stage IV (23) cancer. The site of the cancer was oral cavity, 10; base of tongue, 3; oropharynx, 3; hypopharynx, 4; larynx, 12 (glottic, 6; supraglottic, 6), unknown primary, 2; other, nasal cavity, 1. Of 34 evaluable patients, 16 (47%) had a complete clinical response (CR) and 18 (53%) had a partial response (PR); total clinical response rate was 100%. A pathologic CR at the primary site occurred in 23 of 34 patients (68%; 2 had an unknown primary) who went on to completion radiation at 67 to 72 Gy. After induction chemoradiation 21 patients with N1-3 nodes had neck dissection; 6 (31%) had positive nodes. Twelve patients had residual cancer at the primary site at time of rebiopsy: mandible, 4; maxilla, 1; base of tongue, 2; larynx, 4; floor of mouth, 1; and nasal cavity, 1. All were resected with function-preserving reconstruction. At median follow-up of >12 months, progression-free and overall survivals were 71% and 83%, respectively. CONCLUSION: Preoperative treatment with paclitaxel, carboplatin, and radiation is associated with high CR at the primary site and a high level of organ preservation or functional restoration if ablation is done. PMID- 9374230 TI - Interactions between outcomes and tumor response to preoperative cisplatin sensitized radiotherapy in advanced head and neck cancer. Southern New Jersey Head and Neck Cancer Treatment Group. AB - BACKGROUND: Whether or not tumor response to chemotherapy-sensitized radiation therapy (CTRT) for head and neck cancer leads to an improved outcome is unknown. METHODS: Forty patients who received preoperative cisplatin plus simultaneous radiotherapy for operable stage III and IV head and neck cancer were reviewed retrospectively regarding clinical demographics, staging, and survival status. RESULTS: Twenty-one (57%) patients had a histologic complete response (HCR) and 16 (43%) had a partial (PR) (9) or clinical complete (7) response (CCR). Tumor response of N1 versus N2-3 nodal disease showed 6 (75%) HCR and 4 (25%). Five year disease-free survival overall was 82% for HCR versus 38% for PR/CCR (P <0.05). Disease-specific 5-year survival was 100% for HCR versus 27% for PR/CCR (P <0.002). CONCLUSIONS: Histologic complete response to CTRT for head and neck cancer is associated with increased survival and encouraging disease-free status. Response to CTRT is inversely proportional to lymphatic tumor load. PMID- 9374231 TI - Recurrence patterns with concurrent platinum-based chemotherapy and accelerated hyperfractionated radiotherapy in stage III and IV head and neck cancer patients. AB - BACKGROUND: Stage III and IV squamous cell cancers of the head and neck are often unresectable at presentation and are associated with poor disease-free and overall survival rates. A phase II study using concurrent cisplatin and radiotherapy in advanced head and neck cancer indicated impressive local-regional control and survival with organ preservation. METHODS: A multicentered phase II study was undertaken consisting of 1.8 Gy fraction radiotherapy for 2 weeks followed by 1.2 Gy BID hyperfractionation to 46.8 Gy. Continuous infusion cisplatin 20 mg/m2 was given on days 1 through 4 and 22 through 25. Biopsy of the primary tumor was done at this point, and patients with clinical and pathologic complete response continued with hyperfractionated radiotherapy to 75.6 Gy plus simultaneous carboplatin 25 mg/m2 BID for 12 consecutive days. Residual disease at 46.8 Gy required curative surgery. RESULTS: Seventy-four patients entered the study, and 73 completed their treatment. Twenty were stage III and 54 were stage IV. Fifty patients had involved regional lymph nodes. Treatment was well tolerated with only one grade IV hematologic toxicity. At 46.8 Gy, biopsy revealed a complete response in 75% of the primary sites and 47% of the nodes. Only 12 patients required resection of the primary lesion. At 4 years (median follow-up is 26 months), 29 patients have recurred. CONCLUSIONS: Accelerated hyperfractionated radiotherapy with concurrent chemotherapy in stage III and IV head and neck cancer yields excellent local-regional control with organ preservation. This protocol is intensive, and some patients have distant failures. PMID- 9374232 TI - Intraoperative lymphatic mapping for early-stage melanoma of the head and neck. AB - BACKGROUND: We previously reported dye-directed intraoperative lymphatic mapping and selective sentinel lymphadenectomy for primary cutaneous melanomas draining to the neck lymph nodes. In this study we determined whether combining the dye with a radiopharmaceutical agent would enhance our rate of sentinel node detection. METHODS: One hundred seventeen patients with primary cutaneous melanomas of the upper chest and head and neck underwent preoperative cutaneous lymphoscintigraphy to confirm lymphatic drainage to neck nodes, followed by intraoperative lymphatic mapping and sentinel lymphadenectomy. In 94 cases, isosulfan blue dye was injected at the primary site; in the remaining 23 cases, a 1:3 mixture of radiopharmaceutical and dye was injected, and a hand-held probe was used to determine the radioactive counts. RESULTS: Preoperative cutaneous lymphoscintigraphy identified 129 drainage basins; 12 patients (10%) had dual basin drainage. During intraoperative lymphatic mapping and sentinel lymphadenectomy, 183 sentinel nodes were identified and excised from 120 basins (1.5 nodes/basin). The blue dye alone identified sentinel nodes in 93 of 101 basins (92%). The probe identified sentinel nodes in 28 of 28 basins, only one of which failed to reveal blue-staining sentinel nodes; thus, the probe plus dye identified sentinel nodes in 27 of 28 basins (96%). Histopathologic analysis revealed metastasis in sentinel nodes from 11 patients (12%) who underwent sentinel lymphadenectomy with blue dye alone and in 3 patients (13%) who underwent sentinel lymphadenectomy with dye plus probe. There were no same-basin recurrences over a mean follow-up of 46 months (range 1 to 125). CONCLUSIONS: Selective sentinel lymphadenectomy is a highly accurate method of staging the regional nodes in patients with primary tumors of the head and neck. Although we initially demonstrated the utility of this technique with blue dye alone, our results now suggest that the combination of dye and radiopharmaceutical may be a more sensitive method to detect sentinel nodes. PMID- 9374233 TI - Expression of basic fibroblast growth factor and its receptors by head and neck squamous carcinoma tumor and vascular endothelial cells. AB - BACKGROUND: Basic fibroblast growth factor (bFGF) is a potent angiogenic factor implicated in tumor growth and metastasis. To determine if bFGF and basic fibroblast growth factor receptor 1 (bFGFR1) and 2 (bFGFR2) are upregulated in head and neck squamous cell carcinoma (HNSCC), we measured the distribution and levels of each in HNSCC specimens and control specimens. METHODS: Head and neck squamous cell carcinoma and control tissue specimens were analyzed qualitatively (40 patients, 10 controls) using immunohistochemistry, and quantitatively (26 patients, 8 controls) using immunoassays and graded immunohistochemistry. Control tissue consisted of palatal tissue obtained during uvulopalatopharyngoplasty (UPPP). RESULTS: Immunohistochemical analysis revealed that bFGF, bFGFR1, and bFGFR2 antigens were strongly associated with cancer and vascular endothelial cells in HNSCC. Control tissue had moderate staining of vascular endothelium and no stromal staining. Quantitative analysis of bFGF in tissue homogenates indicated that bFGF levels in cancer specimens were significantly elevated compared with control tissues (420.3 +/- 360.9 ng/mg total protein versus 49.2 +/ 48.7, respectively, P < or =0.05). When analyzed by clinical stage, bFGF levels were significantly higher in stage III patients as compared with stage IV patients (P < or =0.01). When immunohistochemistry results were correlated with clinical stage, bFGF (P < or =0.01), bFGFR1 (P < or =0.001), and bFGFR2 (P < or =0.0001) staining was significantly more intense in the cancer cells of stage III versus stage IV patients. CONCLUSION: Enhanced expression of bFGF and bFGF receptors by cancer and vascular endothelial cells is present in HNSCC, and may contribute to tumor growth and metastasis in HNSCC by mediating angiogenesis. Strategies aimed at decreasing the expression of bFGF and its receptors may be of therapeutic benefit in HNSCC, particularly at an early stage of disease. PMID- 9374234 TI - Cytologic determinants of well-differentiated thyroid cancer. AB - OBJECTIVE: Fine-needle aspiration biopsy (FNAB) is the preferred diagnostic study for evaluating thyroid nodules. Despite its accuracy, many patients undergo thyroidectomy for benign nodules. This study was undertaken to identify risk factors that might increase the specificity of FNAB. METHODS: Medical records of 422 patients who underwent thyroid surgery between 1986 and 1996 were reviewed. All patients had FNAB prior to surgery. RESULTS: Of the 422 patients, 36% had benign cytology, 46% had indeterminate cytology, and 13% had cancer. In the indeterminate group, 29% of patients had cancer at surgery. Of patients with papillary cytology, 84% had malignancies. Five percent of FNABs were nondiagnostic. Neither age, gender, nor tumor size was associated with increased specificity of FNAB. CONCLUSION: There is no subpopulation of patients with indeterminate FNAB cytology at increased risk of having well-differentiated thyroid cancer. PMID- 9374235 TI - Prognostic significance of lymph node reactivity in the control of pathologic negative node squamous cell carcinomas of the oral cavity. AB - BACKGROUND: Identification of high-risk patients and defining prognostic factors may be useful in the treatment of head and neck cancer. The role of the lymph node reactivity is still obscure. The value of the node reactivity pattern as a predictor of tumor control in oral cavity cancer was analyzed. METHODS: Retrospective analysis of patients with oral cavity squamous cell carcinoma (OCSCC), submitted to tumor resection and neck dissection, with pathologic negative lymph nodes (pN0). Dominant node reactivity pattern was defined as lymphocytic predominance (LP), germinal centers (GC), normal (NL), sinus hystiocytosis (SH), and lymphocytic depletion (LD). Clinical and pathological characteristics of patients free of disease (DF) were compared with those of patients with control failure (CF), which included local, regional, and distant recurrences. RESULTS: Of the 26 patients with pN0 OCSCC, prevalence of SH was found in 10 cases, GC in 13, and LD, NL and PL in 1 case each. Comparing CF and DF groups, there was no significant statistical difference regarding: age, gender, performance status index, weight loss, smoking and drinking habits, complementary treatment, average follow-up, tumor grade or thickness, margins, or tumor inflammatory and desmoplastic reaction. Although there was a higher proportion of perineural invasion and larger tumors in the CF group, the difference was not statistically significant either. Germinal centers or LP were noted in only 27% of the CF group and in 73% of the DF group. Collectively, NL, SH, or LD patterns were observed in 73% of CF. This incidence was statistically different from 27% of the DF group (P <0.05). CONCLUSIONS: Lymph node reactivity pattern seems to be a prognostic index in pN0 OCSCC patients. Prospective analysis is advised to confirm these results. Prophylactic neck dissection as a staging procedure could select high-risk patients even when no metastasis is found. PMID- 9374236 TI - Green tea and leukoplakia. The Indian-US Head and Neck Cancer Cooperative Group. AB - BACKGROUND: A feasibility chemoprevention trial of green tea and oral leukoplakia has been conducted. The purpose is to demonstrate the success and pitfalls of conducting such a population-based trial within Indian rural villages. METHODS: Two dosages of green tea were utilized: 3.6 g per day and 5.4 g per day. Compliance was measured using tea package counts and by measuring the blood concentration of the active anticancer compound in green tea, (-) epigallocatechin-3-gallate (EGCG). RESULTS: Following a 3-year planning period, 13 villages were visited, and 1,203 tobacco users were interviewed in order to identify 64 participants suitable for trial inclusion. Of the subsequently 28 consenting individuals entered, 23 remained on protocol for the entire 6-month duration. Overall compliance was excellent, with participants consuming approximately 80% of prescribed packets. CONCLUSIONS: These results provide a basis for continuing international collaborative efforts in conducting population based chemoprevention trials against head and neck cancer. PMID- 9374237 TI - Pediatric rhabdomyosarcoma of the head and neck. AB - PURPOSE: Survival for pediatric rhabdomyosarcoma has improved with the use of multidrug chemotherapy and external beam radiotherapy. This study was performed to determine survival in a cohort of patients treated on one of three multidrug treatment protocols for head and neck rhabdomyosarcoma and to identify factors that place patients at risk for treatment failure. METHODS: Pertinent prognostic variables including age, sex, subsite of origin, resectability, and TNM stage were analyzed by the Kaplan-Meier methods with comparisons between variables performed using the Prentice-Wilcoxon test statistic. RESULTS: Overall 5-year survival was 74% (95% confidence interval 64% to 84%). Local failure accounted for the cause of death in 10 patients, and 8 died of disseminated disease. On univariate analysis, each variable contributing to the TNM staging system was significant in determining survival; invasiveness (P = 0.01), size (P = 0.02), nodal metastases (P <0.01), and distant disease (P <0.01). CONCLUSION: Survival has improved for head and neck rhabdomyosarcoma treated with multimodality therapy. Patients with advanced-stage disease are at greatest risk for treatment failure and require the most aggressive therapy. PMID- 9374238 TI - The predictive value of tumor regression rates during chemoradiation therapy in patients with advanced head and neck squamous cell carcinoma. AB - OBJECTIVE: The value of tumor regression rates in predicting survival outcome during chemoradiation therapy was prospectively evaluated. METHODS AND MATERIALS: Sixty-two patients diagnosed with locally advanced stage III/IV unresectable head and neck squamous cell carcinoma underwent weekly clinical and endoscopic serial assessment of primary and nodal tumor sizes during chemoradiation therapy between July 1993 and September 1995. Chemoradiation therapy consisted of protocol treatment using supradose intra-arterial targeted cisplatin (SIT-P) at 150 mg/m2 four times at weekly intervals along with intravenous sodium thiosulfate at 9 g/m2 and concurrent conventionally fractionated radiotherapy at 1.8 to 2.0 Gy/fraction (fx) to a total dose of 68 to 74 Gy. Tumor reduction was serially measured as a percentage of the original pretreatment size at weekly intervals by the same team of surgical and radiation oncologists. Correlations were then made between tumor regression rates and survival. RESULTS: Complete or near complete regression of disease during chemoradiation therapy as compared with nonresponsive/partially responsive disease was associated with better survival outcome (P = 0.001 and P = 0.013, respectively). Among patients exhibiting complete or near complete regression of disease, rapid tumor reduction (median = 4.2 weeks) was associated with inferior survival outcome when compared with slower disease regression (median = 6.4 weeks, P = 0.007). CONCLUSIONS: Our findings fail to support the "traditional" hypothesis that rapid tumor regression during treatment is predictive of an improved survival outcome. Treatment strategies that alter ongoing therapy based upon initial tumor regression rates should be avoided. PMID- 9374239 TI - Extended anterior craniofacial resection for intracranial extension of malignant tumors. AB - OBJECTIVE: To review our experience with anterior craniofacial resection for malignant neoplasms with intracranial extension. Survival was analyzed in terms of presence of intracranial extension, extent of intradural disease, tumor histology, and histological status of margins. PATIENTS: In a retrospective review made at a tertiary cancer facility, 26 of the 115 consecutive patients undergoing craniofacial resection for malignant lesions of the anterior skull base had intracranial extension, defined as dural and/or brain extension. Survival was evaluated with the Kaplan-Meier product limit method, and comparisons between individual subgroups were performed using the log-rank test. RESULTS: Patients with intradural extension have a statistically worse disease specific survival than patients without intracranial extension (P = 0.05). Surgical margins and tumor histology impact on survival. The incidence of local complications was 42% and of systemic complications, 8%. CONCLUSION: Anterior craniofacial resection is indicated for patients with resectable disease. The complication rate is comparable with that of patients without intracranial extension. Gross total resection with histologically negative margins portends a better prognosis. Esthesioneuroblastoma has a better prognosis than other tumor types. PMID- 9374240 TI - Retinal cell transplants: how close to clinical application? PMID- 9374241 TI - Neuroprotection of the optic nerve in glaucoma. PMID- 9374242 TI - A new generation of algorithms for computerized threshold perimetry, SITA. AB - PURPOSE: The purpose of this work was to develop a new family of test algorithms for computerized static threshold perimetry which significantly reduces test time without any reduction of data quality. METHODS: A comprehensive visual field model constructed from available knowledge of normal and glaucomatous visual fields is continuously updated during testing. The model produces threshold estimates and also estimates of the certainty to which the threshold is known at each point. Testing is interrupted at each test location at predetermined levels of threshold certainty. New time-saving methods are employed for estimation of false answers, and test pacing is optimized. After completion of the test, all threshold estimates are re-computed, taking into account the complete body of patient responses. Computer simulations were used to optimize the different parameters of the new algorithms, to evaluate the relative importance of those parameters, and to evaluate the performance of the algorithm as a whole in comparison with a standard algorithm. RESULTS: Simulated test results obtained with this algorithm were slightly more accurate than those of the Humphrey Full Threshold test algorithm. The number of simulated stimuli presented was reduced by an average of 29% in normal fields and 26% in glaucomatous fields. Actual clinical test time should be further reduced, since the influence of the improved timing algorithm was not included in the simulations. CONCLUSIONS: We applied new methods which take available knowledge of visual field physiology and pathophysiology into account, and employ modern computer-intensive mathematical methods for real time estimates of threshold values and threshold error estimates. In this way it was possible to design a family of testing algorithms which significantly reduced perimetric test time without any loss of quality in results. PMID- 9374243 TI - Peripheral colour contrast thresholds in ocular hypertension and glaucoma. AB - PURPOSE: To evaluate a new test for peripheral colour contrast sensitivity as a tool for early diagnosis of glaucoma. PATIENTS AND METHODS: Peripheral colour contrast sensitivity was measured by a computer and colour monitor system developed by Arden and co-workers. The monitor displays an annulus subtending 25 degrees at the retina. During the test, 45 degrees of the annulus is removed in one of four quadrants. The patient is asked to identify this quadrant, first at suprathreshold levels and then as the colour contrast between the annulus and the background is varied in order to establish the threshold for identification. The tested colours were varied along the protan, deutan and tritan colour confusion axes, respectively. Thirty-three normal subjects, 22 glaucoma patients and 69 ocular hypertensive patients were examined. The ocular hypertensive patients were divided into a low risk group, a medium risk group and a high risk group. RESULTS: The colour contrast thresholds for the glaucoma group and the high risk ocular hypertensive group were significantly (p < 0.001) higher for all three colour axes compared with the normal group. There were also significant (p < 0.05 0.001) differences for all axes between the glaucoma group on the one hand and the ocular hypertensive low risk group on the other hand. There were, however, overlaps in colour contrast thresholds between all groups. CONCLUSION: Although there is a large and statistically significant difference in average colour contrast thresholds between normals and glaucoma patients, it was difficult to find an appropriate cut-off point to separate the two groups. Further studies must clarify the influence of early stages of common diseases such as cataract, diabetes and age-related maculopathy on colour contrast sensitivity. PMID- 9374244 TI - The effect of a shear force on the cell shedding rate of the corneal epithelium. AB - PURPOSE: During blinking the lids apply a shear force to the corneal epithelium. The aim of this study was to determine if a shear force applied to the epithelial surface increases the rate at which cells shed. METHODS: The shedding rate was studied in perfused whole rabbit eyes, and the effect of a shear force examined by exposing the corneas to a stirred solution. Control corneas were exposed to a static solution. The shedding rate and size of shed cells were measured, and the number of terminally differentiated cells on the corneal surface determined after 6 h of perfusion using ethidium bromide. RESULTS: Compared with controls, the shear force increased the cell shedding rate from the corneal surface significantly (p < 0.01, paired t-test). The increase was due to small cells with a longest dimension less than 25 microm. The number of terminally differentiated cells on the epithelial surface did not increase. CONCLUSION: Because of the decrease in size, and the change in appearance of shedding cells, it is proposed that the increase in cell shedding rate was due to an increase in the number of apoptotic cells, and not to an increase in terminally differentiated cells. It is suggested that in the human eye, under adverse conditions, shear forces due to blinking may play a role in creating apoptotic cells. PMID- 9374245 TI - Immunohistochemical characterization of retinal glial cell changes in areas of vascular occlusion secondary to diabetic retinopathy. AB - PURPOSE: To study changes in retinal glial cell components in areas of vascular occlusion secondary to diabetic retinopathy. MATERIAL: The retina from ten eyes of six diabetic patients and from five eyes of five normal controls were studied for immunoreactivity to glial fibrillary acid protein and vimentin (glial cells), S-100 protein (perivascular glial cells), carbonic anhydrase isoenzyme II and CD 57 antigen (Muller cells), and CD-68 antigen (microglia). RESULTS: The study showed increased immunoreactivity to S-100 protein, corresponding to perivascularly located glial cells in the retina from diabetic patients, except for areas of vascular occlusion where this immunoreactivity was absent. Furthermore, the material invading the lumen of former retinal vessels in areas of vascular occlusion showed immunoreactivity to CAH-II and CD-57, suggesting that this material represents ingrowth of retinal Muller cells. CONCLUSIONS: The findings suggest that at least two types of changes in retinal glial cells are involved in the pathophysiology of diabetic retinopathy, i.e. 1) Reactive changes in the perivascular glial cells in the retina, and 2) Muller cell ingrowth into the former lumen of occluded retinal vessels. PMID- 9374246 TI - Fluorometric evaluation of panretinal photocoagulation in diabetic subjects. AB - The effect of panretinal photocoagulation on the blood-retinal barrier was examined by long-term kinetic vitreous fluorophotometry in eight insulin treated diabetic subjects, before and one month after unilateral panretinal photocoagulation. The fluorophotometric investigations revealed an increased permeability-index following this treatment. A further analysis based upon a two compartment fluorescein kinetic model revealed a decreased penetration rate constant together with increased zero-time concentration coefficients for fluorescein following panretinal photocoagulation. No alterations were observed in kinetic parameters in the group of untreated eyes. This points towards a delayed but increased fluorescein penetration to the vitreous following panretinal photocoagulation, probably indicating an increased net flux of fluorescein across the entire retina. In patients with unilateral proliferative retinopathy the permeability-index obtained from eyes with classified proliferative retinopathy was 18.1%, whereas the permeability-index from eyes without proliferative retinopathy was 15.4%. This relatively small difference seems to indicate that the main part of vitreous fluorescence comes from an increased penetration across the entire retina, whereas a direct leakage from the proliferations themselves is less in magnitude. This increased retinal penetration might possibly be caused by affected transport processes for fluorescein within the retina. PMID- 9374247 TI - Value of intraoperative keratometry in predicting outcome of radial keratotomy. AB - PURPOSE: To investigate whether the immediate change in corneal power during radial keratotomy correlates with the long-term postoperative change in subjective refraction, and thereby being predictive for refractive outcome. METHODS: Manual keratometry was performed on 45 consecutively operated eyes of 45 young persons with myopia of 5 dioptres and less and immediately after radial keratotomy. Automated keratometry and subjective spherical equivalent refraction were investigated during a follow-up period of 6 months and correlated to the intraoperative keratometric measurements. RESULTS: On average, the majority of the change in corneal curvature after radial keratotomy took place within 1 min. There was no correlation between the intraoperative curvature change and the changes in curvature measured up to 6 months after surgery. There was a weak significant positive correlation between intraoperative curvature change and the change in subjective refraction at 6 months after surgery (R = 0.48, p < 0.01). The prediction error in estimating subjective refractive changes from intraoperative keratometry changes was, however, similar in patients who had bilateral radial keratotomy. Inclusion of such fellow-eye information together with the age of the patient in a multiple linear regression analysis increased the correlation coefficient from 0.48 to 0.75. CONCLUSIONS: The change in central corneal curvature takes place within minutes after corneal incision. As a single parameter, intraoperative keratometry cannot be used for titrating surgery. Information from the results of first eye radial keratotomy surgery with intraoperative keratometry is, however, predictive for radial keratotomy in the second eye. These findings suggest that a large source to refractive variability after radial keratotomy is related to individual patient factors, such as corneal biomechanics and wound healing. PMID- 9374248 TI - Inflammatory response after endocapsular phacoemulsification or conventional extracapsular lens extraction in the rabbit eye. AB - PURPOSE: We compared the inflammatory response after phacoemulsification and conventional extracapsular lens extraction in New Zealand albino rabbits. METHODS: One eye was selected at random and phacoemulsification was performed. Extracapsular lens extraction was done in the fellow eye. In both eyes a polymethylmetacrylate intraocular lens was implanted into the capsular bag and the wound was sutured with a 9-0 polypropylene continuous suture. The levels of prostaglandin E2 in aqueous humour and wet mass of the iris-ciliary bodies were measured at day 1. The number of white blood cells and protein levels in the aqueous humour were measured at day 1, 3, 7, 14 and 30. Corneal thickness was estimated with pachymetry. RESULTS: Prostaglandin E2 levels and wet masses of iris-ciliary bodies were significantly higher after extracapsular lens extraction, which also induced significantly higher white blood cells counts at day 1 and 3 and higher protein levels at day 7. Extracapsular lens extraction caused more corneal edema at day 3, 7 and 14. CONCLUSION: The results suggest that phacoemulsification induced less surgical trauma with less breakdown of the blood-aqueous barrier. PMID- 9374249 TI - Antibodies against a furosemide binding protein from Ehrlich ascites tumour cells inhibit Na+, K+, Cl- co-transport in frog retinal pigment epithelium. AB - PURPOSE: To investigate whether antibodies against a 100 kDa protein purified by furosemide affinity chromatography from Ehrlich ascites tumour cells could inhibit Na+, K+, Cl- co-transport in the isolated frog retinal pigment epithelium. METHODS: The rate of Na+, K+, Cl- co-transport across the retinal membrane in the isolated frog RPE preparation was measured as the rate of decrease in the intracellular Cl- activity observed after administration of furosemide in the apical bath. The intracellular Cl- activity was measured with double barrelled Cl- sensitive microelectrodes. RESULTS: Incubation of frog retinal pigment epithelium for 30 min with antibodies reduced the rate of Na+, K+, Cl- co-transport by 43%, while leaving all other measured electrophysiological parameters intact. CONCLUSION: The antibodies inhibit Na+,K+,Cl- co-transport in the frog retinal pigment epithelium. This could be due to binding of the antibodies to the co-transporter itself or to a regulatory protein. PMID- 9374250 TI - Transvitreal retino-choroidal biopsy of suspected malignant lesions of the choroid. Follow-up of cases over 7 years. AB - The cases of transvitreal retino-choroidal (TVRC) biopsy from 1987 to 1994 were assembled in order to examine the efficiency, complications and risks to patients. Of 92 biopsies 91 had sufficient material for diagnosis. Eighty (87%) contained malignant tissue, whereas 10 cases were negative and two unsuccessful. Tumours of appropriate size were treated by brachytherapy. Twenty-three large tumours were enucleated primarily. Eight irradiated eyes had to be removed. In 31 cases, therefore, it was possible to examine the whole tumour for changes caused by the biopsy and to compare the typing of the biopsy with that of the whole tumour. In the irradiated eyes histologically viable tumour cells remained mostly in the inner part of the tumour. Scleral necrosis was not found. The technique used appears to be safe. Histological verification is highly recommended before any conservative therapy, inter alia to obtain true statistics of therapeutic results. PMID- 9374251 TI - Effects on intraocular pressure and aqueous flow of various dose regimens of latanoprost in human eyes. AB - PURPOSE: To examine if different dose regimens of latanoprost cause a difference in daytime intraocular pressure (IOP) in normal eyes and if such changes could be attributed to an increase in aqueous flow. METHODS: In a randomised, open, cross over study latanoprost 50 microg/ml was instilled in one eye of 18 volunteers. Three dose regimens (one/three drops once daily or one drop twice daily) were evaluated. IOP was measured at the end of each 14-day treatment period. Aqueous flow and endothelial permeability were assessed by fluorophotometry. RESULTS: All dose regimens reduced IOP significantly (p < 0.001). Once daily applications reduced IOP more than twice daily (p < 0.01). No statistically significant difference in aqueous flow was detected between different treatments. One drop daily increased aqueous flow compared with control eyes (p < 0.05). A similar, but not statistically significant tendency was present with the other regimens. Corneal endothelial permeability was not affected. CONCLUSION: Once daily applications of latanoprost reduce IOP more effectively than twice daily in normal subjects. This cannot be explained by an increase in aqueous flow. PMID- 9374252 TI - Graft survival and risk factors of penetrating keratoplasty for microbial keratitis. AB - PURPOSE: To evaluate graft survival rates and prognostic factors in relation to penetrating keratoplasty for microbial keratitis. METHODS: The records of 95 patients treated with penetrating keratoplasty for microbial keratitis during a twenty-year period were reviewed. Data were analysed by construction of survival curves using the Kaplan-Meier non parametric method. RESULTS: The overall survival of a clear cornea was 72% after one year, 71% after two years and 52% after five years. A significantly lower survival rate (p<0.05) was found in the presence of preoperative local risk factors such as wear of contact lenses and trauma and in inflamed eyes. In contrast, systemic diseases like diabetes, cancer or rheumatoid arthritis did not affect survival and neither did recipient age nor the degree of vascularization of the eye. Male donor buttons showed superior survival compared to female ones (p < 0.05), while females seemed to constitute the best recipients. Recurrence rates of microbial keratitis postoperatively were 11%, 16% and 24% after one, two and five years, respectively. Corresponding graft rejection rates were 9%, 15% and 27%. CONCLUSIONS: Patients suffering from microbial keratitis have a relatively high risk of graft failure. To improve the prognosis care should be taken to minimize local risk factors. Surgery should whenever possible be performed on quiet eyes. The unexpected finding of a better prognosis for male donor buttons might suggest the preferred use of male donors in patients suffering from microbial keratitis, but the observation needs further documentation. PMID- 9374253 TI - Eye size in healthy Swedish children and in children with fetal alcohol syndrome. AB - PURPOSE: This study set out to collect reference data for normal ocular growth and to study the teratological effects of alcohol on eye development. METHODS: Eye size was studied in 92 healthy Swedish children (age 1 month to 16 years) as reference and in 13 children (age 1.4 months to 17 years) with fetal alcohol syndrome (FAS) using ultrasonographic axial length measurements. Another three children with FAS were evaluated by clinical examination only. RESULTS: The control group demonstrated a marked increase in total axial length during the first 2 years of life. Girls with FAS had a shorter total axial length (p = 0.045) than their controls. Both boys and girls with FAS demonstrated a relatively smaller vitreous body than the controls, p = 0.015 and 0.068, respectively. Three children with FAS had severe structural anomalies. CONCLUSION: The observations support previous studies indicating that alcohol has an adverse effect on growth and configuration of the eye. PMID- 9374254 TI - Cataract surgery and pupil size in patients with diabetes mellitus. AB - PURPOSE: Constriction of the pupil during phacoemulsification and intraocular lens (IOL) implantation in patients with diabetes mellitus was studied. METHODS: Before surgery a combination of 0.75% cyclopentolate and 2.5% phenylephrine was applied topically to the eyes of 32 patients with diabetes mellitus and 25 age matched controls. Epinephrine was mixed with buffered saline solution and used during the surgery. The surgical procedure included capsulorhexis, phacoemulsification in the posterior chamber and implantation into the capsular bag of a heparine surface-modified poly(methyl metacrylate) IOL with an optic diameter of 5.0 mm. The durations of phacoemulsification and the whole surgical procedure were recorded. Measurements of the horizontal pupillary diameter were taken before surgery, after phacoemulsification and at the end of the surgery. RESULTS: There was no significant difference in pupil size between controls and the diabetic group before the operation. Surgically induced miosis after phacoemulsification and at the end of operation were significantly more pronounced in the diabetic group than in controls (p < 0.05) (p < 0.05). Phacoemulsification and the entire surgical procedure took significantly longer time when performed in the diabetic eyes (p < 0.05) (p < 0.05). CONCLUSION: We conclude from these data that constriction of the pupil during cataract surgery is more pronounced in diabetic eyes as compared to controls. PMID- 9374256 TI - The effect of heparin-coated intraocular lenses on intraocular pressure following combined trabeculectomy and cataract surgery. AB - PURPOSE: To review the effects on intraocular pressure control of the use of standard and heparin-coated intraocular lenses (IOLs) following combined cataract and glaucoma surgery after a minimum period of 2 years. METHODS: Case note review of all patients with glaucoma who required cataract extraction combined with trabeculectomy and who were randomized to either of the two IOL types. The number of ocular hypotensive medications and the intraocular pressures were recorded pre operatively and at 3, 6, 18 and 24 months following surgery. RESULTS: The two groups (9 receiving standard IOLs and 10 heparin-coated IOLs) were comparable for age, sex and follow-up, as were the pre-operative intraocular pressures and number of treatments. Post-operatively, all patients achieved an intraocular pressure < 21 mmHg at the final visit, with only one patient in each group requiring topical medication, but the standard lens group had a higher intraocular pressure at 2 years (p<0.05). The magnitude of the fall from the pre operative values was greater in the heparin-coated lens group at 2 years after surgery (p<0.02). The presence of a visible drainage bleb occurred equally frequently in the two groups. CONCLUSIONS: Use of a heparin-coated IOL does not adversely affect the intraocular pressure control following combined cataract and drainage surgery. The greater fall in intraocular pressure at 2 years in those receiving a heparin-coated IOL may have occurred by chance. PMID- 9374255 TI - Photorefractive keratectomy for low myopia at 6 mm treatment diameter. A comparison of two excimer lasers. AB - PURPOSE: The aim of the retrospective study was to evaluate the algorithms and the surgical performance of two excimer lasers; the VISX 20/20 and the Summit Omnimed. METHODS: Twenty patients were treated with the VISX-laser and 20 with the Summit-laser. The indications were myopia between -1 to -6 diopters which also allowed correction of astigmatism up to -2 in the VISX patients group. The treatment diameter was 6 mm and the follow-up time was 12 months. The parameters studied were visual acuity uncorrected and corrected, contrast sensitivity in light, dark and glare, endothelial cell count, corneal topography, and subjective estimation of dark vision problems. RESULTS: Both groups showed the same median refraction, -0.3 diopters. All the Summit patients had uncorrected visual acuity of 0.7 or better. In the VISX group 17 patients saw > or = 0.7 uncorrected and all patients saw 0.5 or better s.c. The remaining result parameters showed no statistical differences between the two groups. CONCLUSION: The study does not lend conclusive support for any difference between the results obtained by the two lasers. PMID- 9374257 TI - The effect of posterior vitreous detachment on the prognosis of branch retinal vein occlusion. AB - PURPOSE: Two important complications causing visual loss in retinal branch vein occlusions are vitreous hemorrhage due to retinal neovascularization and persistent macular edema. The aim of this study was to identify the effect of the total posterior vitreous detachment on the disease prognosis. METHODS: Fifty three patients with temporal branch vein obstruction were followed for eighteen months on average. The vitreous conditions of all patients were established, and the effect on persistent macular edema and retinal neovascularization development was statistically investigated. RESULTS: This prospective study shows that total posterior vitreous detachment has a clear preventive effect on both complications. CONCLUSION: Careful vitreous examinations of all patients with branch retinal vein occlusion give us important information about the prognosis and patient management. PMID- 9374258 TI - Senile entropion - cure rate by retractor tightening and horizontal shortening. AB - PURPOSE: In order to clarify the efficiency of two operations aimed at curing the principal causes of senile entropion, a consecutive series of patients were examined. MATERIAL: In 19 lids, the lower lid retractors were tightened transcutaneously and in 45 a simultaneous horizontal lid shortening was performed. Surgery was uneventful in all cases. The patients were reexamined 7-53 months after surgery. RESULTS: In the group with mere retractor surgery were five recurrences; all lids that also had a horizontal shortening were satisfactorily cured. CONCLUSION: Lower eyelid retractor tightening with simultaneous horizontal shortening of the lid is recommended to correct senile operation with a lasting result. PMID- 9374259 TI - Photographic detection of retinopathy in insulin-treated diabetes. A population study in the city of Tartu, Estonia. AB - PURPOSE: To perform a cross-sectional baseline investigation of diabetic retinopathy prevalence and metabolic control. METHODS: Using a register of insulin-dependent diabetes mellitus in Tartu (pop. 104,791), 175 patients were invited to fundus photography; 149 (89%) participated, 99 of them diagnosed with diabetes before the age of thirty. Four Kodachrome 64 photographs per eye were taken with a Canon CR4 - 45NM camera through tropicamide-dilated pupils; slides were projected and systematically graded. Capillary blood samples (n = 132) for HbA1c determination were mailed on filter paper. Following cysteine buffer elution, Mono S ion exchange chromatography was performed (reference range 3.7 to 5.3%). RESULTS: Any diabetic retinopathy was found in 114 patients (76.5%; 95% confidence interval, CI, 70 to 83%); mild to moderate non-proliferative retinopathy in 59 (40%; 95% CI 32 to 48%); severe non-proliferative retinopathy in 29 (19.5%; 95% CI 13 to 26%); proliferative retinopathy in 26 (17%; 95% CI 11 to 24%); 47 patients (32%) needed laser photocoagulation. Vitreous haemorrhage was observed in 9 (6%) of subjects. In patients diagnosed with diabetes before the age of 30 years, prevalence of any retinopathy was 82% (95% CI 73 to 89%) and of proliferative retinopathy 23% (95% CI 15 to 33%). Median HbA1c was 9.7% for women and 8.6% for men (95% CI for difference 0.7 to 2.1%). CONCLUSION: Retinopathy prevalences (76-82%) are the highest reported from population-based studies. Glycaemia levels were very high and should be gradually lowered. Methods capable of validation can be successfully introduced for population-based assessment of hyperglycaemia and retinopathy prevalences. PMID- 9374260 TI - A comparative study of polyacrylic acid (Viscotears) liquid gel versus polyvinylalcohol in the treatment of dry eyes. AB - We conducted a prospective, randomised, single-masked study comparing the safety and efficacy of polyacrylic acid 0.2% (PAA) and polyvinylalcohol 1.4% (PVA) in 85 patients (PAA 43, PVA 42) with dry eyes. The two groups were similar in patient demographics and study parameters at baseline. With treatment, the reduction in total symptoms (gritty or foreign body sensation, burning sensation, dry eye sensation, photophobia, others) and signs (conjunctival hyperaemia, ciliary injection, corneal and conjunctival epithelial staining) score on PAA was significantly greater than that on PVA at both two and four weeks. The daily frequency of instillation of PAA was significantly less than that of PVA on 16 of the 27 (59%) study days. For overall local tolerance there was a significant preference for PAA compared to PVA by both patients and doctors. Only one patient on each treatment had an adverse event and neither was serious. PAA (Viscotears) was as safe as, but better tolerated and more effective than PVA in the treatment of dry eye conditions. PMID- 9374261 TI - Anthrax as the cause of preseptal cellulitis. AB - Anthrax is an infectious disease caused by Bacillus anthracis. It is primarily a disease of domestic animals such as cattle, goats, and sheep; but humans can rarely be infected by contact with infected animals or contaminated animal products. Our case is a 4-year-old boy who was initially diagnosed as preseptal cellulitis, but later he showed the characteristic anthrax lesions with a black necrotic eschar. Scrapings from the necrotic tissue showed gram positive rods and culture grew Bacillus anthracis. The patient responded to intravenous administration of penicillin G, and the lesions resolved, leaving a scar on the right upper eyelid. Eyelid involvement of anthrax is rarely seen in clinical practice, but should be considered in differential diagnosis. PMID- 9374262 TI - Corneal anesthesia in a case with Vogt-Koyanagi-Harada syndrome. AB - PURPOSE: To add clinical features to the description of the Vogt-Koyanagi-Harada syndrome. METHOD: Case report. RESULTS: The case presented with a typical medical history of Vogt-Koyanagi-Harada syndrome, including headaches, low-grade fever, nuchal rigidity, and from the eyes bilateral visual loss, a reaction from the anterior chambers, bilateral uveities with localized exudative retinal detachment from the left. In addition there were tonic pupils, anesthesia of the corneas, and an accommodative deficit. CONCLUSION: Corneal anesthesia, tonic pupils and accommodative impairment can be features of the Vogt-Koyanagi-Harada syndrome. PMID- 9374263 TI - Metastatic bacterial endophthalmitis. A report of four cases all leading to blindness. AB - PURPOSE: To draw attention to the rare but severe entity of endophthalmitis as encountered due to metastatic spread of bacteria. METHODS: We report our experience from four cases of metastatic bacterial endophthalmitis. RESULTS: Systemic infection (Pneumococcus meningitis) was evident in two cases, but in the other two there was no early clue to systemic infection. Eventually, however, endocardial vegetations were disclosed as the source of bacterial emboli (E.coli, peptostreptococcus). In the most atypical patient, magnetic resonance scanning had indicated disseminated brain tumours, and only autopsy revealed the infectious nature of the disease. Ocular ultrasonography being part of the work up, the four eyes under study all showed marked morphological intraocular changes, including 'solid tumour' in the presumed neoplastic case. CONCLUSION: Our cases stress the severity of metastatic bacterial endophthalmitis and the easily missed early diagnosis, even where experienced clinicians are involved. The role of diagnostic ultrasound is discussed. PMID- 9374264 TI - A leiomyoma of the iris documented by immunohistochemistry and electron microscopy. AB - PURPOSE: To report an iris leiomyoma documented in accordance with today's stricter diagnostic criteria. METHODS: Light microscopy, immunohistochemistry and electron microscopy were performed on the 3 mm ball-like, greyish-white vascularized tumour of the iris, close to the sphincter pupillae. RESULTS: Light microscopy of the extirpated neoplasm showed the characteristic appearance of a leiomyoma with densely packed spindle-shaped cells, with oval nuclei and granular cytoplasm. On electron microscopic examination the tumour exhibited the characteristic features of a smooth muscle neoplasm. The immunohistochemistry was consistent with a myogenic tumour because the tumour cells were positive for smooth muscle actin and desmin, but negative for S-100 and melanin. CONCLUSION: The case illustrated the necessity of performing ancillary procedures such as electron microscopy and immunohistochemistry to substantiate a correct, although rare diagnosis. PMID- 9374265 TI - Histopathological and ultrasound biomicroscopy findings in a case of irreversible mydriasis after keratoplasty in keratoconus. AB - This report describes the histopathological and ultrasound biomicroscopy findings of a 35-year-old woman with keratoconus who developed an irreversible mydriasis after keratoplasty. PMID- 9374266 TI - Uveoscleral drainage route. PMID- 9374267 TI - Morphometric characteristics of cryopreserved mesencephalic dopamine neurons in culture. AB - Blocks of embryonic rat mesencephalon were freeze-stored for 1-2 years in liquid nitrogen at -196 degrees C with 7.5% dimethyl sulfoxide (DMSO) as cryoprotectant. After thawing, pooled mesencephalic tissues were mechanically dissociated. The cells, plated at two different densities (4.10[5] and 2.10[5]/cm2) were cultured in a serum-supplemented medium for at least 2 weeks before immunocytochemical staining with highly specific antidopamine (DA) antibodies. The cryopreserved DA immunoreactive (IR) neurons were compared, by means of computerized morphometry, to the fresh ones plated at the same densities. A separate analysis of the dendritic and axonal morphometric parameters revealed that the cryopreserved DA IR cells, whatever the experimental conditions, had significantly larger dendritic fields and, less significantly, larger axonal fields than their fresh counterparts. A principal component analysis, mainly based on the dendritic morphometric parameters, allowed to individualize only two populations (cryopreserved and fresh) among the four groups studied. These findings underline the role of dendrites as potential sites of release and/or re-uptake of dopamine and their possible implications in functionally effective cryopreserved nigral grafts. PMID- 9374268 TI - 5-HT3 receptors in the ventromedial nucleus of the hypothalamus and female sexual behavior. AB - Within the ventromedial nucleus of the hypothalamus (VMN), serotonin exerts a dual role in the control of female rat lordosis behavior. Most emphasis has been placed on 5-HT1A and 5-HT2 receptors, which inhibit and facilitate the behavior, respectively. In the current experiment, a potential role for VMN 5-HT3 receptors in the control of lordosis behavior was examined. Ovariectomized rats, hormonally primed with 25 microg estradiol benzoate and 500 microg progesterone, received bilateral VMN infusions with 100 ng, 250 ng or 500 ng of the 5-HT3 receptor antagonist, tropisetron. In these rats, there was a dose-dependent decline in both the lordosis to mount (L/M) ratio and in the quality of the lordosis reflex with 500 ng tropisetron producing the most consistent change in lordosis behavior. Relative to hormone-primed, ovariectomized rats, lordosis behavior of proestrous females was less affected by VMN infusions with the 5-HT3 receptor antagonist. The 5-HT3 receptor agonist, m-chlorophenylbiguanide (mCPBG), attenuated the effect of tropisetron; of the three mCPBG doses (500 ng, 1000 ng, 1500 ng) examined, 1000 ng was the most effective, perhaps because, alone, 1500 ng mCPBG slightly reduced lordosis behavior. These observations emphasize the potential role for VMN 5-HT3 receptors in the control of lordosis behavior. PMID- 9374270 TI - Prenatal manipulations reduce the proinflammatory response to a cytokine challenge in juvenile monkeys. AB - Two studies were conducted to assess the potential long-term effects of prenatal stress on the cytokine-related inflammatory response in juvenile rhesus monkeys. Subjects were derived from two different pregnancy conditions. Study 1 involved endocrine activation of the pregnant female by daily adrenocorticotropic hormone (ACTH) injection across a 2-week period (days 120-133 post-conception). Pregnant females in Study 2 experienced a psychological stressor, 10 minutes per day, for a 6-week period (days 106-147 post-conception). When the offspring from these pregnancies were 1.5-2 years of age, they were administered recombinant human interleukin-1beta (rhIL-1beta) to stimulate the release of endogenous cytokines, elicit fever, and activate the hypothalamic-pituitary-adrenal (HPA) axis. Cerebrospinal fluid (CSF) and blood levels of interleukin-6 (IL-6) were measured, as well as cortisol levels and body temperature. The prenatal ACTH treatment altered the postnatal response to IL-1beta in juvenile offspring. These monkeys showed a significantly blunted response to the IL-1beta, with smaller increments in blood and CSF levels of IL-6 and diminished temperature responses to the IL 1beta. In contrast, the prenatal psychological stressor was not as potent and did not have lasting effects on this physiological response in juvenile monkeys. IL 1beta also induced significant increases in cortisol secretion, but this adrenal response was comparable in all monkeys. These data suggest that differences in the prenatal environment could have a selective effect on cytokine physiology accounting for individual differences in the inflammatory response. PMID- 9374269 TI - [Gamma-35S]GTP autoradiography allows region-specific detection of muscarinic receptor-dependent G-protein activation in the chick optic tectum. AB - A recently introduced technique of [gamma-35S]GTP autoradiography was used to localize and characterize muscarinic receptor-dependent activation of G-proteins in tissue sections of the chick optic tectum, a brain region with relatively high expression of G-protein-coupled receptors for the neurotransmitter acetylcholine. Within the highly stratified tectal structure, the bulk of muscarinic receptor mediated [gamma-35S]GTP signal was localized to the stratum griseum et fibrosum superficiale with considerably lower binding responses in other tectal layers. Quantitative comparison of [gamma-35S]GTP binding responses in tectal sections and membranes revealed a close match between the two tissue preparations for the response elicited by the cholinergic agonist carbachol, its dose-dependent reversal with the non-selective muscarinic antagonist atropine, its approximately 100-fold sensitivity towards blockade with M1-type (pirenzepine) over M2-type (gallamine) muscarinic antagonists, as well as absolute requirement for micromolar concentrations of GDP (EC50 approximately 10 microM) for the receptor mediated [gamma-35S]GTP response. The pharmacological profile is consistent with that of cm4, a recently cloned chicken homolog of the mammalian m4 muscarinic acetylcholine receptor. Moreover, the strict GDP-dependence of the binding response suggest activation of Gi/o, the inhibitory class of G-proteins. These data provide the first functional characterization of the chick tectal muscarinic receptors. A close match between [gamma-35S]GTP responses in membranes and tissue sections strongly suggest that [gamma-35S]GTP autoradiography offers great potential for studies on G-protein-mediated signaling, with particular use within anatomically restricted regions that are not readily approached with more conventional techniques. It is anticipated that [gamma-35S]GTP autoradiography should greatly facilitate studies on signaling capacity of an individual receptor subtype whilst in its native cellular environment. PMID- 9374271 TI - Structure-dependent differences in the effects of the Aconitum alkaloids lappaconitine, N-desacetyllappaconitine and lappaconidine in rat hippocampal slices. AB - Lappaconitine, a C19 diterpenoid alkaloid from Aconitum sinomontanum has been reported to possess analgesic and antiinflammatory properties in vivo and to inhibit neuronal activity in brain slices. In the present study the effect of lappaconitine has been compared with the effects of its main metabolite N desacetyllappaconitine and the structurally related alkaloid lappaconidine. For comparison of drug effects population spikes and field excitatory postsynaptic potentials (EPSPs) evoked by stimulation of stratum radiatum or the alveus were studied in normal rat hippocampal slices and in slices treated with low Mg2+ medium. At concentrations of 3-100 microM, both lappaconitine and N desacetyllappaconitine inhibited population spikes elicited by stratum radiatum and alvear stimulation as well as the field EPSP recorded in CA1 stratum radiatum. The drug-induced depression of field potential responses was increased with rising stimulus frequency, indicating an activity-dependent mode of action. The effect of N-desacetyllappaconitine on each parameter investigated was significantly stronger than the effect of lappaconitine. Despite the structural relationship, lappaconidine failed to affect neuronal excitability in concentration below 100 microM, and an increase in stimulus frequency did not potentiate its effect. Moreover, lappaconitine and N-desacetyllappaconitine suppressed epileptiform activity induced by bicuculline or by omission of Mg2+ from the bathing medium. PMID- 9374272 TI - Distribution of glutamate receptor subunits in the primate temporal cortex and hippocampus. AB - The distribution of subunits for the N-methyl-D-aspartate (NR1, NR2A/B), alpha amino-3-hydroxy-5-methyl-4-isoxazole propionate (GluR1, GluR2/3, GluR4) and low affinity kainate (GluR5/6/7) ionotropic glutamate receptors was examined by immunocytochemistry in the temporal cortex and hippocampus of the rhesus macaque (Macaca mulatta). Neurons expressing NR1, NR2A/B, GluR2/3, and GluR4 subunits were widely distributed in all of the cortical layers but the overall density of the GluR4-immunopositive neurons was very low. Neurons expressing the GluR1 subunit were found predominantly in cortical layers V and VI while those expressing the GluR5/6/7 subunits were concentrated in layer V and were readily distinguishable by the thick elongate shape of their primary apical dendrites. Subcellular differences in the immunostaining pattern were also noted between the different glutamate receptor subunits. NR1 and NR2A/B immunoreactivity was most pronounced in somatic and primary dendritic compartments and to a lesser extent in cortical and hippocampal molecular layers. GluR1 immunoreactivity was more intense than GluR2/3 in the hippocampal molecular layers whereas GluR4 was undetectable. GluR5/6/7 immunoreactivity was very intense in the dentate molecular layer, and the CA1 pyramidal cells had a subcellular distribution of GluR5/6/7 that was similar to the cortical neurons. Overall, the distribution patterns of the different glutamate receptor subunits was identical in animals that had been ovariectomized and in ovariectomized animals that had subsequently undergone estradiol or estradiol/progesterone hormone replacement. Taken together, these findings demonstrate a differential spatial arrangement of glutamate receptor subunits in the primate temporal cortex and hippocampus, which may have functional significance for the integration of excitatory inputs to these areas. Furthermore, they show that in adult macaques, sex steroids do not play a major role in determining the distribution patterns of these receptor subunits. PMID- 9374273 TI - Fos-like immunoreactivity induced by intraplantar injection of endotoxin and its reduction by morphine. AB - C-Fos-like immunoreactivity (FLI) in the central nervous system, has been associated with the processing of nociceptive information in acute and chronic pain animal models. The aim of this study was to investigate whether intraplantar (i.pl.) injections of endotoxin (ET, 1.25 microg) can induce FLI in the lumbar spinal cord of rats and to assess the effects of morphine injection on c-fos expression. FLI was studied in various groups of rats at 2, 3, 4, 6, 9 and 24 h following ET injections. Labeled neurons were mainly detected in the lumbar segments ipsilateral to the ET-injected leg, with a major peak (71.01 +/- 4.79 positive neurons) at 4 h and a second peak (29.87 +/- 5.97 positive neurons) at 9 h followed by a recovery to the baseline at 24 h after ET injections. Within the laminae, the majority of positive neurons was observed at 2-3 h in laminae I and II and in deep laminae (V and VI mainly) starting at 4 h after ET injections. Rostrocaudally, labeled neurons were observed initially in L4-L5 segments (2-3 h post-ET) after which they extended to L2-L6 segments at 4 h after ET. Morphine injections either i.p. (1 or 2 mg/kg) or i.pl. (50 microg) significantly reduced ET-induced hyperalgesia and simultaneously the FLI. The maximum effect was observed on labeled neurons in the deep laminae (V and VI mainly). We conclude that local injections of ET can induce FLI in the lumbar spinal cord with a temporal and spatial patterns comparable to the described hyperalgesia, and that both FLI and hyperalgesia are reduced by morphine in a dose-dependent manner with a maximal effect shown by the local i.pl. morphine injections. PMID- 9374274 TI - Aggressive behavior in male mice lacking the gene for neuronal nitric oxide synthase requires testosterone. AB - Nitric oxide acts as a neural messenger in both the central and peripheral nervous systems. Mice with targeted disruption of the neuronal isoform of nitric oxide synthase (nNOS - / -) are extremely aggressive relative to wild-type (WT) mice. Male nNOS - / - mice exhibit an increase in the number and duration of aggressive encounters compared to WT animals when tested in a variety of paradigms used to test rodent aggression. This inappropriate aggressive behavior has only been observed in male nNOS - /- mice; nNOS - /- females, like female WT mice, exhibit little or no aggression. The present study sought to test the dependence of increased aggressive behavior in nNOS - / - males on testosterone. Intact nNOS - / - males exhibited elevated levels of aggression relative to intact WT males. Castration reduced aggression in both WT and nNOS - /- males to equivalent low levels. Testosterone replacement restored aggression to precastration levels in both genotypes. These data provide evidence that increased aggressive behavior of nNOS - /- mice, like aggression in WT mice, is testosterone-dependent. PMID- 9374275 TI - Antidromic and orthodromic responses by subicular neurons in rat brain slices. AB - The subiculum forms part of the region of transition between hippocampus and entorhinal cortex and is one of the primary output structures of the hippocampal formation. Intracellular recordings from subicular bursting and non-bursting cell types and field potential recordings were taken in horizontal slices from rat brains. The inputs and outputs of the two cell types were studied for the purpose of reinforcing or refuting the dichotomy proposed on the basis of membrane properties. Some bursting cells were antidromically activated by stimuli applied to the superficial or deep layers of presubiculum, but never by stimuli applied to deep layers of medial entorhinal cortex (dMEC). Some non-bursting subicular neurons were antidromically activated by stimuli applied to dMEC, but never by stimuli applied to presubiculum. Antidromic population events in subiculum were single spikes when deep MEC was stimulated, but were bursts when presubiculum was stimulated, even in the presence of glutamate receptor antagonists. Population bursts consist of 2 or more population spikes with peak to peak intervals of approximately 5 ms. That population bursts occur in slices where excitatory transmission is blocked suggests that such population bursts reflect coincident bursts by individual neurons. Short-latency (< 5 ms) excitatory postsynaptic potentials (EPSPs) were evoked in both subicular cell types in response to single entorhinal, presubicular and CA1 stimuli. Long-latency (> 10 ms) EPSPs were seen in both cell types in response to presubicular, but not entorhinal or CA1 stimulation. Bursting cells responded to brief trains of orthodromic stimuli (2 10 pulses, 5-10 ms interstimulus interval) with a burst of action potentials even when the cell was previously depolarized out of bursting range by current injection. Non-bursting cells responded to brief trains of orthodromic stimuli with repetitive firing (< or = 1 spike/stimulus) at all holding potentials. Spike intervals could reach those seen in bursts by bursting cells. It is concluded that: (1) the distinction between bursting and non-bursting subicular neurons is a dichotomy and cells do not change their identity when activated antidromically or orthodromically; (2) the outputs of the two cell types may be different: bursting cells projected to presubiculum and non-bursting cells projected to entorhinal cortex; and (3) non-bursting cells can, when repetitively stimulated, fire repetitive spikes with interspike intervals in the range of intervals seen in bursts. PMID- 9374277 TI - Impaired brain development and reduced astrocyte response to injury in transgenic mice expressing IGF binding protein-1. AB - Numerous reports indicate that insulin-like growth factor-I (IGF-I) has a critical role in brain development, that it contributes to neuronal survival and that its activity is regulated by a family of IGF binding proteins (IGFBPs). In the present study, brain development was investigated in transgenic (Tg) mice that overexpress rat IGFBP-1 under the control of phosphoglycerate kinase promoter. Adult Tg mice had significantly decreased brain weight (299 +/- 17 vs. 499 +/- 11 mg), brain DNA content (684 +/- 8 vs. 810 +/- 31 microg) and brain protein (37 +/- 1 vs. 48 +/- 2 mg) compared with wild-type (Wt) mice and these deficits were already evident at birth. In Tg mice, myelin staining was generally reduced and there was a diminished thickness of the corpus callosum. The total area of hippocampus and dentate gyrus were significantly reduced by 55% and 72%, respectively. Bromodeoxyuridine labeling of proliferating cells in 3-day-old mice was markedly reduced by 41% in the dentate gyrus and by 19% in ventricular zones of Tg mice. Reactive astrogliosis reflected by morphology and glial fibrillary acidic protein expression of astrocytes in response to a mechanical lesion was substantially less in Tg compared with Wt mice. Mixed glial cell cultures from Tg animals were significantly less responsive to stimulation of proliferation by IGF I than cultures from Wt mice. We conclude that overexpression of IGFBP-1 impairs brain development and reduces glial cell proliferation in response to injury. PMID- 9374276 TI - Effects of oxidative stress on the expression of limbic-specific protease neuropsin and avoidance learning in mice. AB - We evaluated the effects of oxidative stress in mouse brain induced by the intraperitoneal injection of diethyldithiocarbamate (DDC) on gene expression of the novel serine protease, neuropsin, and on shock-avoidance learning. The level of neuropsin mRNA in the hippocampal pyramidal neurons increased at 2 h after DDC treatment and decreased thereafter. At 7 days neuropsin mRNA significantly decreased to 60% of the pretreated control level and then returned to the control level at 30 days. Genes for tissue plasminogen activator, manganese superoxide dismutase, and heat shock protein did not differ in DDC-treated mice vs. the control group at 7 and 30 days. The shuttle-box avoidance learning was retarded at 7 days after DDC administration. However, it recovered to the control level at 30 days after DDC administration. The results suggest that generation of reactive oxygen species has an important role in neuropsin transcript in the limbic areas which might be related to the disturbance in avoidance learning. PMID- 9374278 TI - Clonidine reduces hyperpolarization-activated inward current (Ih) in rat hypoglossal motoneurons. AB - We used intracellular recording techniques to investigate the actions of clonidine on hypoglossal motoneurons (HMs) in rat brainstem slices. Clonidine (10 100 microM) produced a small (2-6 mV), dose-dependent hyperpolarization in HMs, accompanied by an increase in peak input resistance (RN). It also slowed the time course of the depolarizing 'sag' of the voltage response to constant hyperpolarizing current steps. These effects were mimicked by the alpha2 adrenoceptor (alpha2-AR) agonist guanabenz, but not by the Ih-imidazoline receptor agonists moxonidine or rilmenidine. Recorded in single-electrode voltage clamp mode, clonidine decreased input conductance of HMs and reduced the amplitude of a hyperpolarization-activated inward current (Ih). Clonidine's effect on Ih was three-fold: it shifted the half-activation voltage (V1/2) in the hyperpolarizing direction (by 4.4 +/- 0.7 mV at a dose of 10 microM), decreased the maximal current (by approximately 20%), and slowed the time course of Ih activation at all voltage steps. At the most hyperpolarized potential steps, clonidine slowed activation of Ih dramatically, yielding a striking increase in the activation time constant. The alpha2-AR antagonists yohimbine and idazoxan reduced clonidine's effect on V1/2 and on the Ih activation time course, but neither blocked clonidine's reduction of the maximal current, nor its strong slowing of Ih activation at the most hyperpolarized steps. We were unable to mimic or occlude clonidine's actions with the adenylate cyclase inhibitor SQ 22536 nor with the non-specific protein kinase inhibitor H-7. We conclude that clonidine hyperpolarizes HMs via a reduction of the amount of Ih that is active at rest, and that the response is mediated in part by alpha2-ARs. Some effects of clonidine on these neurons do not appear to be receptor-mediated, and may be due to physical block by clonidine of Ih channels. PMID- 9374279 TI - Augmentation of LTP induced by primed-bursts tetanic stimulation in hippocampal CA1 area of morphine dependent rats. AB - The effects of chronic morphine administration on the development of Long-term potentiation (LTP) were investigated at the Schaffer collateral-CA1 pyramidal cell synapses of the rat hippocampal slices using primed-bursts tetanic stimulation. Significant enhancement of orthodromic population spike (OPS) was found for all stimulus intensities after tetanic stimulation. OPS enhancement was greatest when tested with low to mid-range stimulus intensities (25 and 50 microA). There was also significant decrease in OPS delay. These responses were similar in slices from both control and morphine dependent rats. At all delivered stimulus intensities, the amount of LTP of OPS in slices from dependent rats was larger than that of control slices. However, these differences in LTP of OPS were significant at low stimulus intensities. These findings suggest that chronic morphine administration had induced changes in CA1 neurocircuitry which modulated synaptic plasticity during high frequency stimulation and appeared as augmented LTP. PMID- 9374280 TI - Nerve regeneration in a 'pseudo-nerve' graft created in a silicone tube. AB - The pseudo-nerve, which contains longitudinal Schwann cell columns without axons and surrounded by perineurium-like tissue but no axons (Q. Zhao, L.B. Dahlin, M. Kanje, G. Lundborg, Brain Res. 592 (1992) 106-114), was applied as a graft to repair nerve defect in rats. Creation of the pseudo-nerve was accomplished by inserting the proximal and distal stumps of a cut sciatic nerve into a silicone tube. The proximal insert was cut far proximally to prevent axons from entering the tube. After 4 weeks, the pseudo-nerve was harvested, trimmed into a 10-mm long graft and transplanted into a corresponding defect of the contralateral sciatic nerve. Nerve regeneration through the pseudo-nerve was examined by pinch reflex test and neurofilament staining after 6 days or by morphology after 4, 6 or 8 weeks. The results showed that the pseudo-nerve could induce nerve regeneration to a similar extend as a real nerve graft. The neurobiological composition of the pseudo-nerve and the factors influencing its formation were also studied. By double staining of S-100 and laminin we found that the longitudinally organized Schwann cell columns in the pseudo-nerve were surrounded by basal laminae and ensheathed by a layer of vascularized perineurium-like tissue. Macrophages (ED1 and ED2) and their products interleukin-1beta (IL-1beta) and transforming growth factor-beta1 (TGF-beta1) were constantly present in the pseudo-nerve. Besides, the size of tube was a crucial factor in influencing pseudo-nerve formation, e.g. a thicker pseudo-nerve was formed in tubes with larger diameters or shorter gap lengths. No pseudo-nerve was formed when the gap was 15 mm long. When both proximal and distal inserts were isolated nerve segments the pseudo-nerve was still formed but thin, probably because of compromised vascular supply. Taken together, the results suggested that the pseudo-nerve contains the essential neurobiological elements to induce successful axonal elongation. PMID- 9374281 TI - Reduced dopamine turnover in the basal ganglia of depressed suicides. AB - We have measured the concentrations of dopamine, and the dopamine metabolites homovanillic acid (HVA) and dihydroxyphenylacetic acid (DOPAC), in five brain regions from suicide victims with a firm retrospective diagnosis of depression, and matched controls. The suicides were divided into those free of antidepressant drugs and those in whom prescription of antidepressant drugs was clearly documented. DOPAC concentrations were significantly lower in caudate, putamen and nucleus accumbens of antidepressant-free suicides compared to controls. In antidepressant-treated suicides, lower concentrations of DOPAC were observed in the basal ganglia, reaching statistical significance in caudate. Lower DOPAC concentrations were largely restricted to those suicides who died by non-violent methods. There were no significant differences in dopamine and HVA concentrations in either suicide group compared to controls, although there was a trend for HVA concentrations to be lower in suicides. This study provides evidence for reduced dopamine turnover, as judged from reduced DOPAC levels, in depressed suicides, although we cannot exclude the possibility that this may be due to ingestion of toxic agents. PMID- 9374282 TI - Autoradiographic evidence for differential G-protein coupling of 5-HT1A receptors in rat brain: lack of effect of repeated injections of fluoxetine. AB - The present study examined the distribution of [3H]8-OH-DPAT-labeled 5-HT1A receptors and their degree of coupling to G proteins in the hypothalamus and several other brain regions. In addition, we also investigated the effects of repeated injections of fluoxetine on the density and G protein coupling of 5-HT1A receptors in hypothalamic nuclei and other brain regions using autoradiography. Male rats received daily injections of either fluoxetine (10 mg/kg, ip) for 3, 7, 14 and 22 days, or saline for 22 days. 5-HT1A receptors were labeled by 2 nM [3H]8-hydroxy-2-(dipropylamino)tetralin ([3H]8-OH-DPAT) in the absence or presence of guanylylimidodiphosphate (Gpp(NH)p, 10[-5] M) to determine the percentage of 5-HT1A receptors coupled to G proteins. 5-HT1A receptor densities ranged from 7 to 63 fmol/mg tissue equivalent among hypothalamic nuclei. Similarly, the degree of G protein coupling to 5-HT1A receptors varied markedly among hypothalamic nuclei (from 14% to 61%) and among other brain regions (from 17% to 85%). Fluoxetine did not alter the density or the degree of coupling of 5 HT1A receptors in any brain regions. These data indicate marked regional differences in the degree of G protein-coupled 5-HT1A receptors and suggest that fluoxetine-induced desensitization of hypothalamic 5-HT1A receptors is not mediated by changes in receptor density or G protein coupling. PMID- 9374283 TI - Distribution of tonin- and kallikrein-like activities in rat brain. AB - Tonin- and kallikrein-like activities were investigated in different regions of the rat brain. The highest values of specific tonin activity, expressed as picomoles of angiotensin II liberated per minute per milligram of protein, were found in the neurohypophysis (359 +/- 190) and in the archicerebellum (200 +/- 68). The highest level of total tonin activity (picomoles of angiotensin II liberated per minute) was observed in the archicerebellum (902 +/- 308) which retained 97% of total tonin activity of whole cerebellum. Tonin activity was not detected in the cortex of cerebellum and in the choroid plexus. Low to intermediate values of specific (1.09 +/- 0.33 to 5.32 +/- 2.37) and total (1.38 +/- 0.55 to 93.00 +/- 49.30) tonin activity were observed in adenohypophysis, cerebellar nuclei, hypothalamus, thalamus, midbrain, pons, medulla and neurohypophysis. The lowest values of specific (0.11 +/- 0.05) and total (0.69 +/ 0.31) activities were observed in the hippocampus. Kallikrein-like activity was expressed as picomoles of p-nitroaniline liberated per minute per milligram of protein. No activity was detected in the neurohypophysis. For other regions, the values of the specific activity ranged between 72 +/- 18 and 282 +/- 14 except for the choroid plexus which was 5 +/- 2. The total kallikrein activity was also homogeneous ranging from 330 +/- 100 to 1870 +/- 112. For the choroid plexus and adenohypophysis the total kallikrein activity was 2.0 +/- 0.8 and 27 +/- 11, respectively. PMID- 9374284 TI - Neural activity and intracellular Ca2+ mobilization in the CA1 area of hippocampal slices from immature and mature rats during ischemia or glucose deprivation. AB - To investigate the correlation between neural activity and intracellular Ca2+ ([Ca2+]i) mobilization in immature and adult brain during ischemia (hypoxia and glucose deprivation) and deprivation of glucose, hippocampal slices were prepared from 7-, 10-day-old and adult rats. Population spikes (PS) and antidromic responses (AR) were recorded in the pyramidal cell layer of the CA1 area as an index of neural function. [Ca2+]i mobilization of the stratum radiatum in the CA1 area was measured using the fluorescent dye fura-2 AM. The rise in [Ca2+]i occurred earlier in the adult animal and the decay times for the orthodromic PS and antidromic responses were shorter in the adult during ischemia. The field potentials and antidromic responses decreased substantially prior to the elevation of [Ca2+]i in both developing and adult brains. Furthermore, ATP levels decreased substantially before the elevation of [Ca2+]i during ischemia. These results suggest that neural activity and intracellular Ca2+ homeostasis in the immature rats brain are more resistant to energy failure than adult rats and that neuronal activity in the developing and adult brain is impaired initially by energy depletion during ischemia. In the immature animal, during glucose deprivation, the antidromic responses were slowly decayed or even failed to extinguish and [Ca2+]i levels were maintained for a longer period or even failed to rise in spite of the rapid loss of PS. Furthermore, ATP levels were well preserved at the time of PS loss. These results agree well with our previous reports showing that glucose plays an important role in the preservation of synaptic transmission in addition to its major function as an energy substrate. PMID- 9374285 TI - Effects of 2,4-dichlorophenoxyacetic acid on central nervous system of developmental rats. Associated changes in ganglioside pattern. AB - Neonate rats were treated with 2,4-dichlorophenoxyacetic acid (2,4-D) from the 7th or 12th until the 17th or 25th postnatal day. Two drug dosages were used: 70 and 100 mg/kg body weight of 2,4-D. At the 17th day of age, no changes were observed in body weight, protein and DNA content. However, 25-day-old treated pups showed diminutions in body and brain weight, protein and DNA levels, depending on doses and period of treatment. With respect to ganglioside levels, few changes were observed in treated animals until the 17th day of age. However, at the 25th day, with higher dose and longer treatment a diminution in all parameters analyzed was observed. These results suggest a delay in CNS development when pups were exposed to a very severe chemical injury with 2,4-D. On the other hand, when the chemical injury was not too severe, the brain would be capable to trigger biochemical mechanisms producing a plasticity response which is expressed as changes in ganglioside content and composition. PMID- 9374286 TI - Preganglionic parasympathetic neurons projecting to the sphenopalatine ganglion contain nitric oxide synthase in the rabbit. AB - We have investigated the possible presence of nitric oxide synthase (NOS) and choline acetyltransferase (ChAT) in brainstem preganglionic parasympathetic neurons projecting to the sphenopalatine ganglion in rabbits, using combined retrograde axonal tracing and immunohistochemistry. Retrogradely labeled neurons were observed in the ipsilateral rostral medulla and caudal pons, in a region laterodorsal to the facial motor nucleus. Double-labeling experiments demonstrated that 75 +/- 5% of retrogradely labeled neurons contained NOS immunoreactivity, while all of retrogradely labeled neurons contained ChAT immunoreactivity. These observations suggest that nitric oxide could influence cholinergic transmission from preganglionic endings in the sphenopalatine ganglion. PMID- 9374287 TI - Association of cholinesterases with amyloid in extracellular neurofibrillary tangles. AB - Double-labeling techniques conclusively demonstrated that extracellular neurofibrillary tangles immunoreactive for beta protein were also positive for cholinesterases. Ultrastructurally, cholinesterases decorated bundles of amyloid like filaments, which appeared intermingled with straight filaments and cellular processes. A lighter labeling of esterases was also seen over most straight filaments. These observations extend the consistent association of cholinesterases with fibrillary beta-amyloid protein to a new location in neurofibrillary tangles. PMID- 9374289 TI - Calretinin-like immunoreactivity in the Ruffini endings, slowly adapting mechanoreceptors, of the periodontal ligament of the rat incisor. AB - The distribution and ultrastructural localization of calretinin (CR)-like immunoreactivity (-LI) were investigated in the lingual periodontal ligament of rat incisors. Some thick nerve fibers within the nerve bundle displayed CR-LI; these CR-like immunoreactive (-IR) nerve fibers entered the alveolar half of the lingual periodontal ligament of the incisor where dendritic terminal arborization was exhibited. Thin and beaded CR-IR nerve fibers were rarely observed in the periodontal ligament. Observations of adjacent sections immunostained with protein gene-product 9.5 (PGP 9.5) revealed that most, if not all, PGP 9.5-IR nerve terminals showing a dendritic arborization expressed CR-LI. Immunoelectron microscopic observations showed that electron-opaque immunoreaction products were localized in the axoplasm of the axon terminals, except for the mitochondria, which were surrounded by Schwann sheaths and multiple-layered basal lamina. Neither cell bodies, the cytoplasmic extension of terminal Schwann cells, nor other cellular elements such as periodontal fibroblasts exhibited CR-LI. The present findings suggest that Ruffini endings, an essential mechanoreceptor in the periodontal ligament and categorized as a slowly adapting mechanoreceptor, express CR-LI, and that CR may participate in the Ca2+ homeostasis against external stimuli in the periodontal Ruffini endings. PMID- 9374288 TI - Post-transcriptional elevation of mouse brain Mn-SOD protein by mercuric chloride. AB - Alterations in gene expression, protein content and enzyme activity of brain Mn SOD following mercuric chloride (HgCl2) exposure were examined in ICR male mice. Subcutaneous administration of HgCl2 (1 mg Hg/kg) resulted in a significant increase (4-fold) in the brain Mn-SOD content at 6 h after injection while the total mercury concentration was about 0.11 microg/g of brain. The enhancement of Mn-SOD protein caused by HgCl2 was completely abolished by pretreatment with dexamethasone (3 mg/kg) 1 h prior to HgCl2 administration, suggesting involvement of inflammation in inorganic mercury-induced increase in the antioxidant enzyme. This increase in level of Mn-SOD content coincided with a substantial rise in the enzyme activity; however, Northern blot analysis revealed that the induction of protein level was not due to that of its gene expression. The results of the present study indicate that mouse brain Mn-SOD appears to undergo post translational modification by the environmental toxic metal, and induction of the antioxidant enzyme could be of an initial response to the metal-induced oxidative stress. PMID- 9374290 TI - Neuronal recovery after moderate hypoxia is improved by the calpain inhibitor MDL28170. AB - The role of calcium-activated proteolysis in hypoxic neuronal injury was investigated using an in vitro slice model of moderate hypoxia that mimics many features of an ischemic penumbra. The calpain inhibitor, MDL28170, significantly improved the recovery of synaptic responses in hippocampal slices following prolonged, moderate hypoxia without hypoxic depolarization. This finding further implicates calpain-mediated proteolysis in the development of neuronal injury following moderate metabolic challenge such as occurs in regions of partial ischemia. PMID- 9374291 TI - Zinc distribution in the brain of Nagase analbuminemic rat and enlargement of the ventricular system. AB - 65ZnCl2 was intravenously injected into Nagase analbuminemic rats (NAR), which have a genetical mutation affecting albumin mRNA processing and lack serum albumin, to test the hypothesis that albumin is necessary for zinc (Zn) transport into the brain. One hour after injection, 65Zn was largely concentrated in the choroid plexus of NAR as well as normal parental Sprague-Dawley rats (SDR). Six days after injection, in both groups, the 65Zn concentration in the choroid plexus decreased, with increases in other brain regions. The finding that there was no significant difference in brain distribution of 65Zn between NAR and SDR suggests that Zn transport into the brain and its distribution through the blood cerebrospinal fluid barrier as well as the blood-brain barrier are not dependent on serum albumin. A most interesting observation was that the cerebral ventricles were considerably enlarged in NAR. PMID- 9374292 TI - Age-related alterations in immunoreactivity of the midsized neurofilament subunit in the brainstem reticular formation of the cat. AB - In the present study, we compared the immunoreactivity of the midsized subunit of neurofilaments (NF-M) in the brainstem reticular formation of adult and old cats. There was a dramatic decrease in immunoreactivity in most reticular nuclei in the old cats. The most obvious reduction in these regions occurred in dendritic arborizations. In contrast, a small number of nuclei showed a slight increase in immunoreactivity in the aged animals. The age-related changes in immunoreactivity indicate that there is an alteration of NF-M content in reticular neurons and their processes in old age. Such changes in NF-M content may be the basis for the alterations in the morphology of reticular neurons in aged animals. PMID- 9374293 TI - Sleeter Bull, 1887-1968: a brief biography. PMID- 9374294 TI - Effect of degradable and escape protein and roughage type on performance and carcass characteristics of finishing yearling steers. AB - We evaluated protein sources for finishing steers in two randomized complete block design experiments. Experiment 1 used 144 steers (334 kg) with 2 x 3 factorially arranged treatments. Basal diets contained .9% urea or 5.6% soybean meal (SBM) and were either not supplemented or supplemented with additional protein (2%) from blood meal-corn gluten meal (BMCG) or SBM. Steers fed urea containing diets consumed 4.6% (P < .10) more feed than those fed SBM supplemented basal diets. On the basis of carcass weights, steers fed diets containing SBM as the basal protein source were 3.8% (P < .10) more efficient than those fed urea-containing diets; supplying additional SBM improved gain efficiency (G/F) 4.3% (P < .10) compared with BMCG. In Exp. 2, 384 steers (367 kg) were fed diets containing 1.0% urea (DM basis) and 10% roughage as either sorghum silage (four diets) or alfalfa hay (two diets). Additional protein was either not provided or provided (2%) as SBM, sunflower meal (SFM), or a 50:50 (N basis) SBM:SFM blend in silage-containing diets; for diets containing alfalfa, additional protein was either not provided or provided (2%) as SBM. Averaged across roughage source, added SBM tended (P = .16) to increase ADG. Dressing percent decreased (P = .09) with added SBM but was higher (P = .04) with alfalfa as roughage source. Feeding alfalfa vs sorghum silage as the roughage source increased carcass adjusted ADG 4.3% (P = .06) and G/F 4.8% (P = .02). Supplementing high-grain diets with SBM enhanced diet utilization, but BMCG was of little value. PMID- 9374295 TI - Postweaning growth and reproduction characteristics of heifers sired by bulls of seven breeds and raised on different levels of nutrition. AB - Heifers produced from sires of seven breeds (Hereford, Angus, Belgian Blue, Piedmontese, Brahman, Boran, and Tuli) and Angus, Hereford, and MARC III (four breed composite) cows were evaluated. Weaned heifers were placed in three treatment groups of moderate nutrition (15.8 Mcal ME/d), 80% of moderate nutrition (12.6 Mcal ME/d), or fed as a mixed-breed group (16.3 Mcal ME/d). Average daily gain (ADG) from 228 d of age through breeding was measured. There was a sire breed x group interaction (P < .0001) for ADG in the drylot. Sire breeds differed in their 365-d BW (P < .0001), and 365-d BW of heifers in the low group (315 +/- 4 kg) were lighter (P < .0001) than those of heifers in the high group (346 +/- 4 kg). During breeding, heifers that had been in the low group in the drylot had a higher ADG (.58 +/- .02 kg/d) than heifers in the high group (.39 +/- .03 kg/d). Age of heifers at puberty did not differ (P = .06) between the low (362 +/- 5 d) and high groups (357 +/- 5 d). Heifers from MARC III (358 +/- 5 d) and Angus (358 +/- 6 d) dams reached puberty at a younger age than did heifers with Hereford dams (380 +/- 9 d). Age at which puberty was expressed differed with sire breed (P < .001). The proportion of heifers that were pregnant at palpation (.90) did not differ between sire breeds (P = .24), dam breeds (P = .40), or group (P = .56). Breed differences in postweaning ADG and in the manner in which the population expresses puberty allow for selection of breed types that will optimize cow herd performance. PMID- 9374296 TI - Effect of steam-flaked sorghum grain density on performance, mill production rate, and subacute acidosis in feedlot steers. AB - Two trials were conducted to determine the effects of steam-flaked sorghum grain bulk density on animal performance, cost of production, and propensity to induce ruminal acidosis in feedlot steers. In Trial 1, 336 yearling steers (343 kg; SEM = .346) were fed diets for 125 d that contained sorghum grain (82.5%, DM basis) flaked to .283 (L), .322 (M), or .361 (H) kg/L (i.e., 22, 25, and 28 lb/bu). Steers fed L consumed 3.2% less DM than those fed H (linear, P < .05), resulting in 6.9% lower ADG (linear, P = .02) and 3.6% lower gain efficiency (linear, P < .15). Sorghum grain flaked to M and L had 16 and 46% greater starch gelatinization than H (measured using differential scanning calorimetry; linear, P = .002). Dressing percentage increased linearly (P < .05) with increasing flake density, but no other carcass measurements were affected by treatment. Increasing flake density increased mill production rate linearly (P < .01), resulting in the lowest energy usage per unit of flaked grain for the H treatment. Trial 2 was an acidosis challenge study that incorporated six ruminally cannulated steers (422 kg; SEM = .129) into a replicated 3 x 3 Latin square experiment. Reducing flake density resulted in linear reductions in ruminal pH following intake challenge at 3, 33, and 36 h after the d-12 challenge (P < .05). There was a linear increase in the area between the pH vs time curve and a line at pH 5.5 (P < .01) and 5.0 (P = .09) with decreasing flake density (28.0, 25.2, and 18.2 pH-hours below 5.5 and 9.6, 7.3, and 3.9 pH-hours below 5.0 for L, M, and H, respectively). Cattle consuming L also tended to have higher VFA concentrations (mM) at 36 h after challenge (P = .12). There was no significant treatment effect on ruminal lactate. Flaking sorghum grain to .283 and .322 kg/L resulted in reduced intake and poorer animal performance compared with .361 kg/L (58.7% starch gelatinization), higher susceptibility to subacute acidosis, and higher costs of production. PMID- 9374297 TI - Influence of sire misidentification on sire x year interaction variance and direct-maternal genetic covariance for weaning weight in beef cattle. AB - Biased estimates of the genetic correlation between direct and maternal effects may occur when sire x year interaction (SY) effects are ignored in analytical models used to estimate (co)variance components for weaning weight in beef cattle. Using simulation, sire misidentification was explored as a source contributing to estimates of SY variance. Identifications were falsified for 20% of sires of nonparents only or for 20% of sires of all animals. Sire misidentification influenced estimates of genetic and environmental parameters. In populations in which misidentification occurred only in nonparents, heritability estimates for direct growth were reduced, and heritability estimates of maternal effects were inflated. Also, spurious SY variance and direct-maternal covariance were produced. Direct-maternal covariance was biased in a positive direction, and SY variance was on the order of 1 to 3% of the phenotypic variance. PMID- 9374298 TI - Segregation analyses for presence of major genes affecting growth, backfat, and litter size in Dutch Meishan crossbreds. AB - Presence of major genes was investigated for two growth traits, backfat thickness, and two litter size traits in the F1 and F2 population of a cross between Meishan and European "White" pig lines. Segregation analyses were performed in a Bayesian setting, estimating the contribution of background polygenes and the contribution of a possible major gene to the expression of the traits considered. In a first analysis, F1 and F2 crossbred data were evaluated; different error variances were fitted for F1 and F2 observations. In the first analysis, significant contributions of major-gene variance were found for the two growth traits, backfat thickness, and litter size at first parity. In a second analysis, F2 data were evaluated to determine whether biases were introduced in the joint analysis of F1 and F2 data. In the second analysis, no major genes were found for growth traits. Major genes affecting backfat and litter size at first parity were confirmed. The gene identified to affect backfat is a dominant gene; the homozygous recessive genotype has approximately 6 mm of additional backfat. The gene identified to affect litter size at first parity also is a dominant gene; the homozygous recessive genotype produces five to six fewer pigs per litter. PMID- 9374299 TI - Genetic evaluation by BLUP in two-breed terminal crossbreeding systems under dominance. AB - To obtain estimates of breeding values by BLUP using Henderson's mixed-model equations, it is necessary to invert the covariance matrix for each random effect in the model. In a model in which the genotypic value is included as a random effect (genotypic model), it is necessary to invert the genotypic covariance matrix. Under additive inheritance, the inverse of the genotypic covariance matrix can be computed efficiently. Under dominance inheritance, however, an efficient method to invert the genotypic covariance matrix has not yet been developed, especially for crossbred populations. Thus, the use of a genotypic model for BLUP is not suitable for genetic evaluation in large, crossbred populations. We present an equivalent model in which the genotypic effect is partitioned into additive and dominance effects. With this equivalent model, methods used for within-breed genetic evaluation by BLUP can be used for a two breed terminal cross under dominance. PMID- 9374300 TI - Influence of dominance relationships on the estimation of dominance variance with sire-dam subclass effects. AB - Two data sets from the USDA Livestock and Range Research Laboratory were analyzed to study dominance variance and the influence of dominance relationships. The first consisted of 4,155 birth weight (3,884 weaning weight) records of inbred USDA Line 1 Herefords. The second consisted of 8,065 birth weight (7,380 weaning weight) records from a line-cross experiment with five lines. Two models were used. Both included fixed effects of year-sex of calf and age of dam, and covariates for calving date, inbreeding of animal, and inbreeding of dam. For the second set, additional covariates were line composition and heterozygosity coefficients. Random effects were direct and maternal additive genetic, maternal permanent environment, sire-dam subclass, and residual. Model 1 considered sire dam subclasses unrelated. Model 2 related sire-dam subclasses with a parental dominance relationship matrix. Variance components were estimated using REML. Differences between estimates with Model 1 and 2 were unimportant except for dominance variance. For the first data set, estimates with Model 2 of relative genetic direct and maternal variances, direct-maternal correlation, permanent environment, and dominance variances for birth weight were .35, .13, -.02, .03, and .25, respectively, and they were .39, .11, .04, .06 and .14 for the second data set. For weaning weight, the first data set estimates were .20, .15, -.37, .19, and .11, respectively, and they were .16, .20, -.07, .18, and .18 for the second data set. Changes, decreases and increases, in estimates of dominance variances may be due to increased information from relationships and family types other than full-sibs. The assumption of unrelated sire-dam subclasses might not be appropriate for estimation of dominance variance in populations with many dominance relationships among sire-dam classes. PMID- 9374301 TI - Discrimination between shepherds by lambs reared under artificial conditions. AB - We studied the ability of 32 lambs reared artificially in groups of four to discriminate between their shepherd and an unknown shepherd. Half of the lambs were bottle fed in isolation by one shepherd during the first 3 wk. The other half was fed alternately by three shepherds. Lambs had no visual contact with humans for the next 3 wk. Lambs were weaned at 6 wk of age and reared together with the minimum human contact necessary for rearing management. Lambs were tested at 3, 6, and 14 wk of age, investigating the effect of the rearing conditions on the response to isolation and to reunion with the known or an unknown shepherd. During tests, lambs were observed 1) in isolation for 1 min, 2) in the presence of a shepherd who entered and squatted at one end of the pen for 1 min, trying to touch the lambs if they approached, 3) again in isolation for 1 min. Early rearing management (one vs three shepherds) had no significant effect on any criteria studied. Lambs vocalized and moved less when in the presence of the shepherd than when isolated. They vocalized less, moved less, approached more quickly, and interacted more with the known than with an unknown shepherd. The difference persisted after 3 wk spent without visual human contact. However, no difference was evident at 14 wk of age. The effect of shepherd knowledge is clearly demonstrated by this experiment after an intensive early period of contact. PMID- 9374302 TI - Prepartum behavior in swine: effects of pen size. AB - Gravid Yorkshire sows assigned to one of three pen sizes on d 109 of gestation, were continuously observed for 72 h before parturition. Pens included a 2.1- x .7 m rectangular farrowing crate (n = 6), a small, square pen 2.1 x 2.1 m (n = 5), and a large, square pen 4.2 x 4.2 m (n = 5). Body positions were recorded at 30-s intervals. Other behaviors were recorded using the one-zero method of sampling at 1-min intervals. Sows became more active as they approached farrowing. They stood, sat, lay with legs under, changed positions, drank, urinated, defecated, rooted the floor and pipes, mouthed the waterer and pipes, and pawed the floor more (P < .05) during the 24 h before the birth of the first pig than during the previous 2 d. Position changes, rooting the floor, and pawing frequency peaked during the 6 h preceding parturition and show promise as predictors of parturition. During the 24 h preceding the birth of the first pig, farrowing crate sows stood, rooted the floor, and pawed less and sat, lay, and changed positions more than sows in either pen (P < .05). No differences (P > .05) among pens were noted for lying with legs under or out, eating, drinking, urinating, defecating, rooting the pipes, mouthing the pipes. or mouthing the waterer. Pipe biting and other behaviors commonly thought to be caused by confinement stress occurred in all three pen sizes and seem to be components of nest-building, expressed inappropriately, in a barren environment. PMID- 9374303 TI - Preference for flavored wheat straw by lambs conditioned with intraruminal infusions of acetate and propionate. AB - We hypothesized that volatile fatty acids in rumen fluid are feedback signals that can condition food preferences or aversions in sheep. Three predictions were tested based on this hypothesis: 1) low doses of sodium propionate or sodium acetate condition preferences, but high doses condition aversions (Exp. 1 and 2); 2) preferences are not caused by osmotic load (Exp. 3 and 4); and 3) low doses of mixtures of acetate:propionate condition preferences (Exp. 4). In Exp. 1, 2, and 4, lambs were divided into four groups (10 lambs/group), and lambs in Exp. 3 were divided into two groups (five lambs/group). In all experiments, alfalfa pellets were the basal diet. On even days, half of the lambs were offered chopped wheat straw containing a distinctive flavor, whereas the other half received straw with a different flavor. During straw ingestion, different groups of lambs received intraruminal infusions of different concentrations (4, 8, or 12% of the daily DE received) of sodium propionate (Exp. 1), sodium acetate (Exp. 2), NaCl at osmotic loads equivalent to those when propionate supplied 4% of the daily DE received (Exp. 3), or different proportions of sodium acetate:sodium propionate (55:45 or 75:25% of the DE of the infusion [4% of the daily DE received]), or equimolar amounts of NaCl (Exp. 4). On odd days, the flavors were switched, and no infusions were administered. After 8 d of conditioning, lambs were offered a choice of wheat straw with the two distinctive flavors. Lambs preferred the flavor paired with the lowest doses of propionate (P = .07) and acetate (P = .08) but avoided the highest doses (P < .001). Excesses of VFA may condition aversions due to increases in rumen fluid osmolality and(or) excessive rates of supply of energy or sodium to the rumen. Lambs also preferred flavored straw associated with combinations of acetate and propionate (P < .001), especially at the highest concentration of propionate (P = .10). Lambs avoided NaCl in Exp. 3 (P < .001) and did not form preferences for NaCl in Exp. 4 (P > .05). Thus, osmolalities were not responsible for flavor preferences. In conclusion, our results support the hypothesis that food preferences and aversions reside along a continuum that depends on the amount of VFA infused. PMID- 9374304 TI - Prolonged colostrum feeding enhances xylose absorption in neonatal calves. AB - Colostrum contains numerous components that influence gastrointestinal development in neonates. To test the influence of differences in duration of colostrum feeding in newborn calves on gastrointestinal absorptive capacity, .5 g xylose/kg BW was administered on d 5 of life. Calves of group GrC6 were fed colostrum from the first six milkings on the first 3 d and then milk replacer. Calves of group GrC1 were fed first colostrum only and then milk replacer in the same amounts as calves of group GrC6. Calves of group GrM were fed only milk replacer: they received no colostrum. The rise of plasma xylose after xylose intake was greater (P < .05) in GrC6 and GrC1 than in GrM but not significantly greater in GrC6 than in GrC1. Basal and mean plasma glucose concentrations on d 5 of life were higher in GrC6 than in GrM, but there was no difference in the magnitude of its postprandial rise. The data indicate greater xylose absorptive capacity in calves after prolonged colostrum intake compared with calves fed only milk replacer. PMID- 9374305 TI - Forage substitution in a grain-based diet affects pH and glycogen content of semimembranosus and semitendinosus rabbit muscles. AB - The effects of nutritional level on glycogen content and pH of semimembranosus (SM) and semitendinosus (ST) rabbit muscles were investigated. Rabbits weaned at 30 d of age were fed one of three diets in which grain had been replaced with 0, 15, and 45% coast cross bermudagrass (Cynodon dactylon Pers.). Muscles were sampled at .5, 3.5, 6.5, and 24 h after slaughter. Results showed that these isoenergetic and isoproteic diets did not affect the total number of days required for rabbits to attain 2 kg of live weight. The SM muscle of animals fed the 0% forage diet exhibited higher glycogen content than the SM muscle of rabbits maintained on 15 and 45% forage diets at all sampling times. At .5 h after slaughter, the glycogen content of SM from the 15 and 45% dietary groups was decreased by 65 and 79%, respectively, in relation to the 0% dietary group. For ST, glycogen content was higher only at the first sampling time for the 0% forage diet (diet with no addition of bermudagrass) when compared with animals maintained on diets with forage. For SM and ST, significant differences in muscle pH among dietary groups was observed at 6.5 and 24 h after slaughter, and rabbits maintained on a 45% forage diet showed a higher ultimate pH than animals fed 0 or 15% forage diets. These results demonstrate that grain replacement with forage in diets for rabbits causes a decrease in glycogen content in two types of muscles and results in higher ultimate pH, which may affect the shelf-life quality of the meat. PMID- 9374306 TI - Estimated frequency of the RN- allele in Swedish Hampshire pigs and comparison of glycolytic potential, carcass composition, and technological meat quality among Swedish Hampshire, Landrace, and Yorkshire pigs. AB - The frequency of the dominant RN- allele (Rendement Napole) was estimated in purebred Swedish Hampshire pigs (n = 208) by using the estimated glycogen content in the longissimus muscle at slaughter (glycolytic potential; GP). Carriers (n = 177) and noncarriers (n = 31) of the RN- allele were compared with purebred Swedish Yorkshire (Y, n = 208) and Swedish Landrace (L, n = 114) pigs with respect to GP and carcass composition. Technological meat quality was compared between the RN phenotypes from the Hampshire breed and Yorkshire pigs. The distribution of GP deviated from a normal distribution in all three breeds. Hampshire pigs with GP > or = 183 micromol lactate equivalents per gram wet weight were regarded as carriers of the RN- allele (RN-/RN-, or RN-/rn+), and those constituted 85% of all Hampshire pigs evaluated, giving a frequency of .61 for the dominant allele (RN-). The RN- carriers had higher GP than noncarriers, Landrace, and Yorkshire pigs, but noncarriers and Landrace did not differ regarding GP. The two RN phenotypes did not differ in carcass composition, but the carriers were leaner than Landrace and Yorkshire, with larger proportions of meat plus bone in ham and back. Noncarriers and Yorkshire did not differ in leanness, but both these groups were leaner than Landrace. The RN- carriers had lower Napole yield (cured cooked muscle) and higher drip loss than noncarriers and Yorkshire, but in comparison with noncarriers they also had lower shear force values. In conclusion, the frequency of the RN- allele is high in purebred Swedish Hampshire. Most of the effects of the allele on technological meat quality (i.e., ultimate pH, water-holding capacity, and technological yield) found in crossbred pigs seem also to be consistent for purebred pigs. However, the RN- allele exerted less influence on meat content in purebred pigs. PMID- 9374307 TI - Relationships of meat characteristics of two lines of rabbits selected for litter size and growth rate. AB - We measured meat characteristics of 46 commercial rabbit carcasses from two synthetic breeds selected for litter size or growth rate. Color measurements (CIELAB) were made on several muscle surfaces. Color measured on the muscular aponeurosis indicated a pale carcass at most of the points; Chroma (C*) and hue (H*) varied from 3.71 and 31.1, respectively, for longissimus at the 7th lumbar vertebra to 14.3 for C* of trapezius and 56.1 for H* of biceps femoris. Color of the longissimus cut surfaces differed substantially from the exterior surface color. The 1st lumbar vertebra cut also differed from the 7th lumbar vertebra cut. The pH of the biceps femoris was 5.80 and that of the longissimus was 5.75. Meat fat content of half a carcass was 5.28%. The first four principal components of an analysis with color and pH measurements of the longissimus and biceps femoris and meat fat content explained 68% of the variance. The entire set of variables was well summarized by the lightness (L*) and Chroma of the longissimus muscle exterior surface measured at the 4th lumbar vertebra, longissimus pH, and meat fat content. When the data were projected on the plane defined by the first two principal components, two separate groups of points appeared, corresponding to the animals of each breed. PMID- 9374308 TI - An evaluation of ultrasound and nuclear magnetic resonance spectroscopy to measure in vivo intramuscular fat content of longissimus muscle of pigs. AB - Intramuscular fat content (IMF) of longissimus muscle of pigs growing from approximately 20 to 100 kg was measured in vivo using biopsies after complete or localized anaesthesia, ultrasound and 1H nuclear magnetic resonance (NMR) technology. Three lines of pigs, with 60 animals each, were available. Biopsies were taken from the same pigs at 20, 60, and 100 kg, and fat was extracted for gravimetric determination. At 20 kg, ultrasound images were collected, and in vivo 1H NMR spectroscopy was applied. A-mode ultrasound measurements were collected at 60 and 100 kg. The overall mean value of IMF was 1.60 +/- .56% at 20 kg, 1.53 +/- .50% at 60 kg, and 1.71 +/- .60% at 100 kg. Interactions between lines and body weight were observed. No statistically significant differences were found between methods at 20 kg. No significant correlations were found between the A-mode ultrasound measurements and the mean values of the gravimetric measurements. No visible pain or infections were observed in relation to the collection of a single biopsy. The ultrasound method in combination with image analysis is advantageous from the labor point of view and will also improve welfare of pigs in case of repeated sampling. However, further research is necessary to make the technology sufficiently reliable. A correlation between IMF and backfat thickness was not found. PMID- 9374309 TI - Concentrations of selected vitamins and selenium in bison cuts. AB - We analyzed individual cuts from clod (Triceps brachii), ribeye (Longissimus thoracis), top round (semimembranosus), and top sirloin (Gluteus medius) from 12 fed bison bulls for content of selected vitamins and selenium. The bulls came from producers in the United States and Canada and had consumed concentrate diets plus hay free choice for at least 180 d. The mean nutrient concentrations of all of the bison cuts combined were as follows (per 100 grams of wet weight): .045 mg thiamin, .253 mg vitamin B6, 2.131 microg vitamin B12, no detectable vitamin C, .848 microg vitamin A, .047 mg alpha-tocopherol, .013 mg tau-tocopherol, and 25.464 microg selenium. The nutrient content values did not differ (P > .05) among the cuts of meat. Cuts from individual bulls were different (P < .05) with regard to alpha- and tau-tocopherols, selenium, and vitamin A but not with regard to thiamin, vitamin B6, and vitamin B12. Nutrient concentrations, with the exception of one nutrient, of five bison from the same producer were similar. Great variation was observed between the alpha- and tau-tocopherols, selenium, and vitamin A contents among bison bulls but not among cuts of meat. PMID- 9374310 TI - Carcass characteristics, the calpain proteinase system, and aged tenderness of Angus and Brahman crossbred steers. AB - We used 69 steers of varying percentage Brahman (B) breeding (0% B, n = 11; 25% B, n = 13; 37% B, n = 10; 50% B, n = 12; 75% B, n = 12; 100% B, n = 11) to study the relationship between carcass traits, the calpain proteinase system, and aged meat tenderness in intermediate B crosses. Calpains and calpastatin activities were determined on fresh longissimus muscle samples using anion-exchange chromatography. The USDA yield and quality grade data (24 h) were collected for each carcass. Longissimus steaks were removed and aged for 5 or 14 d for determination of shear force and 5 d for sensory panel evaluation. Even though some yield grade factors were affected by the percentage of B breeding, USDA yield grades did not differ (P > .15) between breed types. Marbling score and USDA quality grade decreased linearly (P < .01) with increasing percentage of B breeding. Shear force after 5 and 14 d of aging was higher (P < .05) in the 100% B steers than in all other breed types, which were not significantly different. Sensory panel tenderness and connective tissue scores decreased linearly (P < .05) with increasing B breeding. A quadratic effect was also noted for tenderness and connective tissue scores; 37% B steers received the highest scores. A similar response was found in mu-calpain activities; the 37% B steers had the highest activities. Conversely, calpastatin activity increased linearly (P < .01) with increasing percentage B breeding. These data show strong linear relationships between calpastatin activity (positive), marbling score (negative), and percentage B breeding, suggesting a possible combined effect of these traits on aged tenderness of intermediate Brahman crosses. PMID- 9374311 TI - Apparent ileal digestibilities of amino acids in newly weaned pigs fed diets with protease-treated soybean meal. AB - Apparent ileal digestibilities of amino acids were determined in pigs fed cornstarch-based diets with untreated or protease-treated soybean meal as the protein source. Sixteen pigs were fitted with a modified post valve T-cecum cannula on d 14, 15, and 16 after birth and then returned to their sows until d 20 when they were weaned. Twelve of the pigs were selected for the study, which was conducted according to a two-period balanced change-over design. Treatments consisted of soybean meal that was 1) untreated (SBM), 2) processed by incubation (1:2 wt/vol distilled water adjusted to pH 4.5, for 16 h at 50 degrees C; CI SBM), 3) sprayed with protease (supplied at 1 microL/g of soybean meal; PS-SBM), and 4) processed by incubation, as for CI-SBM, with protease in the water at the rate of 1 microL/g of soybean meal (PI-SBM). Each period consisted of 5 d of adaptation to diets followed by three 8-h collection periods (total of 24 h) that alternated with 8-h periods in which digesta were not collected. Apparent CP digestibilities were similar (P > .05) at 70.4, 72.4, 65.2, and 70.3% for the SBM, CI-SBM, PS-SBM, and PI-SBM diets, respectively. Corresponding amino acid digestibilities were also similar (P > .05), ranging from 62.5, 67.5, 57.9, and 65.0% for alanine to 83.5, 83.4, 78.7, and 84.7% for arginine. Apparent digestibilities were less (P < .05) for Period 1 (on d 7 after weaning) than for Period 2 (on d 16 after weaning). In conclusion, protease treatment of soybean meal had no effect on ileal digestibilities of CP and amino acids in newly weaned pigs. PMID- 9374312 TI - Endogenous recoveries and true ileal digestibilities of amino acids in newly weaned pigs fed diets with protease-treated soybean meal. AB - Endogenous recoveries and true ileal digestibilities of amino acids were determined in pigs fed cornstarch-based diets with untreated or protease-treated soybean meal as protein sources. Twelve pigs, fitted with a modified post valve T cecum cannula on d 14, 15, and 16 after birth, were weaned on d 20 and assigned to one of four diets according to a two-period balanced change-over design. Diets consisted of soybean meal 1) untreated (SBM), 2) incubated (1:2 wt/vol in distilled water adjusted to pH 4.5, for 16 h at 50 degrees C; CI-SBM), 3) sprayed with protease (1 microL/g of soybean meal; PS-SBM), and 4) incubated, as for CI SBM, with protease in the water (PI-SBM) at the same application rate as that for PS-SBM. Each period consisted of 5 d of adaptation to diets followed by collection of ileal digesta on d 6 and 7 to determine the apparent ileal amino acid digestibilities of the diets. On d 9, guanidinated meals were fed, followed by a 24-h continuous collection of digesta. Recoveries of chromic oxide and dysprosium from the guanidinated meals were 96.0 +/- .5 and 94.5 +/- 1.1%, respectively. Endogenous amino acid recoveries were similar (P > .05) for SBM, CI SBM, and PS-SBM but less (P < .05) for PI-SBM. True digestibilities were also less (P < .05) for PI-SBM than for the other meals. Recoveries of endogenous branched-chain and aromatic amino acids were less (P < .05) during Period 2 than during Period 1, suggesting dietary change- and(or) age-dependent adaptive increases in the secretions of pepsin and pancreatic proteases. In conclusion, protease treatment did not improve the true digestibilities of amino acids in soybean meal fed to newly weaned pigs. PMID- 9374313 TI - Effect of increasing dietary vitamin A on bone density in adult dogs. AB - There has been an increase in vitamin A fortification of livestock feeds resulting in increased residual vitamin A in organ meats, which are often used in canned dog foods. The effect on bone density of feeding various concentrations of vitamin A in a canned dog food product was investigated. Thirty-two random-source dogs were assigned to four treatments in a randomized complete block design. The diets contained 15,000, 50,000, 116,000, or 225,000 IU vitamin A/1,000 kcal ME. Diets were fed up to 1 yr. Computed tomography was used to determine bone density of the right tibia at 0, 3, 6, 9, and 12 mo. Computed tomography is a more sensitive technique for determining bone density in vivo than conventional x rays. There were no differences (P > .10) in tibia bone or marrow density in any of the dogs fed the various concentrations of vitamin A. There was no interaction of time x diet on bone density (P > .05) or bone marrow density (P > .05). In addition, there were no changes in serum alkaline phosphatase, calcium, or phosphorus. These results indicate that concentrations of vitamin A three times the recommended maximum safe amount (71,429 IU/1,000 kcal ME) are not detrimental to normal bone health in dogs. Therefore, these data support the hypothesis that canines are less sensitive to excess vitamin A in the diet than some other mammals. PMID- 9374314 TI - Utilization of phytate and nonphytate phosphorus in chicks as affected by source and amount of vitamin D3. AB - Commercial and laboratory-strain crossbred chicks responded (P < .01) markedly to 1alpha-hydroxycholecalciferol (1alpha-OH D3) during the 2nd and 3rd wk of life. Bone-ash responses exceeded 50% when this compound was added at 20 microg/kg to phosphorus (P)-deficient corn-soybean meal diets containing surfeit levels (25 microg/kg) of cholecalciferol (D3). Phosphorus excretion was decreased (P < .01) and, thus, retention was increased (P < .01) when 1alpha-OH D3 was supplemented. A P-deficient (.10% P) casein-amino acid purified diet, devoid of D3, was used to determine whether 15 microg/kg of D3 was sufficient to facilitate optimal absorption of the nonphytate P contained in this diet. Bone ash responded to .075% P addition (KH2PO4), and chicks fed diets with .175% nonphytate P exhibited further bone-ash responses to 15 microg/kg of D3 or 10 microg/kg 1alpha-OH D3. Higher levels of either of these D3 compounds did not produce additional responses. This suggested that 15 to 25 microg/kg of D3 in a P-deficient corn soybean meal diet (.28% phytate P and .14% nonphytate P) is more than adequate to facilitate optimal absorption of the nonphytate P present in the diet. A P deficient casein-dextrose diet (.13% nonphytate P and 15 microg/kg D3) was fed in the final chick assay, and chicks fed this diet did not show bone ash responses to 1alpha-OH D3 or to microbial-derived phytase (1,470 units/kg). Thus, with P deficient corn-soybean meal diets containing at least 15 microg D3/kg, 1alpha-OH D3 supplementation markedly increased weight gain and bone ash because it increased the utilization of phytate P. PMID- 9374315 TI - Effects of dietary selenium and vitamin E on boar performance and tissue responses, semen quality, and subsequent fertilization rates in mature gilts. AB - Three experiments involving 192 crossbred boars evaluated the effects of dietary Se (0 or .5 ppm) and vitamin E (0 or 220 IU/kg) on growth, tissue Se, and alpha tocopherol concentrations, and on semen quality and its subsequent effect on fertilization rate in mature gilts. Diets formulated used torula yeast and dextrose or cornstarch as the basal feedstuffs and were provided from weaning through sexual maturity. The basal diets averaged .063 ppm Se and 3.46 mg alpha tocopherol/kg diet. Experiment 1 was a 2 x 2 factorial and conducted as a randomized complete block design in six replicates. Boars were allotted at weaning (initial BW 7.7 kg) with growth and feed performance determined to 145 kg BW. Five boars were killed at weaning and three from each treatment group at periodic intervals to 145 kg BW. Serum and tissue Se and alpha-tocopherol concentration and glutathione peroxidase (GSH-Px) activity were subsequently determined. No performance benefit from either nutrient was demonstrated. Tissue (serum, liver, and testis) GSH-Px activity and Se and alpha-tocopherol concentrations were higher (P < .01) at each period when that respective nutrient fortified the diet. Testis GSH-Px activity increased from weaning to 145 kg BW even when Se was not added to the diet. Experiment 2 was conducted after training three boars from each treatment group of Exp. 1 for semen collection. From 9 mo of age and for a 16-wk period, semen was collected three times weekly and the volume, sperm concentration, motility, and percentage of normal and abnormal sperm were determined. Boars fed either the nonfortified Se or vitamin E diets had sperm with lower motilities (P < .01) and a higher percentage of sperm cells with bent and shoehook tails (P < .01). Diets low in added Se seemed to have a greater detrimental effect on the percentage of motile and abnormal sperm than diets inadequate in vitamin E. Sperm cells had a high concentration of Se and alpha-tocopherol, and a high GSH-Px activity. Experiment 3 was conducted using the boars from Exp. 2; 34 mature gilts were inseminated at 12 and 24 h after estrus. Gilts were killed 5 to 7 d postcoitum and the reproductive tracts were recovered. The semen from boars fed the nonfortified Se diet had a lower fertilization rate of oocytes with fewer accessory sperm penetrating the zona pellucida. The results from these experiments indicate that dietary Se and vitamin E can affect boar semen quality, but the greater effect seemed to be from Se. PMID- 9374316 TI - Evaluation of spray-dried animal plasma and select menhaden fish meal in transition diets of pigs weaned at 12 to 14 days of age and reared in different production systems. AB - We conducted two experiments with pigs weaned at 12 to 14 d of age to evaluate the effects of adding spray-dried animal plasma (SDAP) and select menhaden fish meal (SMFM) to the diets fed from 5 to 19 (Exp. 1) and 7 to 21 d (Exp. 2) after weaning. This 14-d period represents the transition from the nutrient-dense diet fed to all pigs after weaning to the simpler corn-soybean meal-based diet fed to all pigs for an additional 14 (Exp. 1) or 7 d (Exp. 2) after the experimental period. Pigs averaged 5 kg at the start of the experimental period. In Exp. 1, pigs had a high health status and were weaned to an off-site nursery (SEW) and fed 12 experimental diets in a 3 (0, 2.5, or 5% SDAP) x 4 (0, 2.5, 5, or 7.5% SMFM) factorial arrangement. Diets were formulated to contain 1.6% lysine and contained 20% dried whey, 5% soybean oil, and 2.5% spray-dried blood meal. The SDAP and(or) SMFM replaced corn and soybean meal on an equal lysine basis. Average daily gain and ADFI were not affected by treatment during any period of the experiment. Gain:feed was improved by the addition of SDAP (linear, P < .05) and SMFM (linear, P < .07) during the period from 5 to 19 d. Over the 33-d experiment, SDAP and SMFM improved (linear, P < .05) gain:feed. In Exp. 2, pigs were weaned on-site to an all-in/all-out by room nursery and fed diets identical to those fed in Exp. 1, with 0 or 2.5% SDAP and 0, 2.5, or 5% SMFM in a 2 x 3 factorial arrangement. The addition of 2.5% SDAP improved ADG and gain:feed during the period from 7 to 14 d (P < .05) and 0 to 28 d (P < .10), but not over the period from 7 to 21 d. The addition of SMFM did not affect ADG during any period, but it resulted in a quadratic improvement in gain:feed during the periods from 7 to 14 (P < .05) and 7 to 21 (P < .10) d. These results suggest that high-health SEW pigs respond less to SDAP and SMFM in the transition diet than pigs with a lower health status reared in an on-site nursery. The data further suggest that formulation of transition diets should consider the type of production system if pig performance and diet cost are to be optimized. PMID- 9374317 TI - Immunocytochemical localization of prolactin and growth hormone in the equine pituitary. AB - The ultrastructural and immunoreactive staining characteristics of cells containing prolactin (lactotropes) and growth hormone (GH; somatotropes) in the anterior pituitaries of gonadally intact pony mares were studied at the electron microscopic level. Lactotropes included two morphological subsets: Type I cells were larger and contained large, dense, polymorphic granules that were scattered throughout the cytoplasm; Type II cells were smaller and contained small, dense, polymorphic granules that were predominantly found in peripheral areas of the cytoplasm. Lactotropes constituted 5 to 16% of the total number of cells in the pituitary. Somatotropes were medium-sized cells containing uniform, large, dense secretory granules. The somatotropes contained the largest secretory granules in the pituitary and represented 11 to 26% of the total number of cells. Type I lactotropes and somatotropes were readily distinguishable without immunocytochemical staining. Double-labeling of pituitary sections allowed for characterization of cells that contained both hormones (mammosomatotropes). These cells were morphologically indistinguishable from Type I lactotropes and constituted 6.5 to 16.5% of the total number of cells. Results from this study demonstrated that there are two cell populations that contain only prolactin (Type I and II lactotropes) and one cell population that contains only GH (somatotropes) in the equine pituitary, and an additional subset of cells that contains GH and prolactin in the same secretory granules. PMID- 9374318 TI - Arginine supplementation increases weight gain, depresses antibody production, and alters circulating leukocyte profiles in preruminant calves without affecting plasma growth hormone concentrations. AB - The hypothesis that dietary L-arginine (L-Arg) supplementation would increase growth hormone (GH) secretion and antibody production in preruminant calves was tested. Sixteen newborn calves were randomly assigned to either Arg+ or Arg- treatment groups. Both groups were fed a single dose of Colostrx within 6 h after birth followed by milk replacer twice daily until weaning. Beginning with the Colostrx feeding, calves in the Arg+ group were supplemented with L-arginine at 500 mg kg x BW(-1) x d(-1), and the Arg- group received equivalent, but unsupplemented, diets. All calves were immunized against keyhole limpet hemocyanin (KLH) on d 4 and received a booster vaccination on d 14. The Arg+ treatment increased (P < .05) plasma L-Arg and urea concentrations an average of 2.8-fold and 26%, respectively, during the 4-wk supplementation period. Average daily gain (ADG) of Arg+ calves was increased (P < .10) during wk 1, 3, and 5 of life. The Arg+ treatment depressed (P < .05) total and KLH-specific IgG concentrations in plasma and caused a decrease (P < .01) in circulating leukocyte numbers. Differential counts revealed that the decrease in circulating leukocyte numbers was due to decreases in absolute numbers of lymphocytes, monocytes, and neutrophils. The Arg+ diet did not affect mean plasma GH concentrations during the first 3 wk of life, but GH mean concentrations were decreased (P < .01) during wk 4 due to depressed (P < .10) pulse amplitudes. The decrease in GH mean concentrations during wk 4 was paralleled by lower (P < .10) plasma IGF binding protein-3 concentrations. These data show that supplementary L-Arg does not increase plasma GH concentrations, but it increases ADG, depresses KLH antibody production, and alters circulating leukocyte populations in preruminant calves. PMID- 9374319 TI - Effects of exogenous somatostatin and cysteamine on net nutrient flux across the portal-drained viscera and liver of sheep during intraduodenal infusion of starch hydrolysate and casein. AB - We used eight Polypay wethers (36 +/- .6 kg BW) fitted with hepatic portal, hepatic venous, mesenteric arterial and venous, and duodenal catheters in a crossover design experiment to determine the influence of somatostatin (SRIF) on splanchnic metabolism. Each crossover period consisted of 14 d, with net flux of nutrients and hormones (venoarterial differences x blood flow) measured on d 14. Before flux measurements, wethers received an i.v. dose (0 h) of either 0 (vehicle) or 50 mg x kg BW(-1) x 10 min(-1) cysteamine (CSH, SRIF-depleting agent) followed by a continuous duodenal infusion (h 10 to 22) of a starch hydrolysate-casein solution. Six sets of arterial, portal, and hepatic blood samples were obtained (h 12 to 16), after which a primed (10 microg), continuous jugular infusion of SRIF-14 (5.0 microg x kg BW(-1) x h(-1)) was initiated and sampling protocol repeated (h 18 to 22). Cysteamine administration increased (P < .01, vs control) portal and hepatic blood flow in the absence of exogenous SRIF (CSH x SRIF, P < .01). Net portal-drained viscera (PDV) release of glucose, alpha amino N, ammonia N, beta-hydroxybutyrate, and oxygen consumption were decreased (P < or = .10) and lactate release increased (P = .005) during SRIF infusion. The CSH increased (P < .05) PDV release of beta-hydroxybutyrate and insulin and increased (P = .09, CSH alone vs control) net release of glucose in the absence of exogenous SRIF. Exogenous SRIF increased (P = .10) and CSH decreased (P = .09) net hepatic glucose output, whereas liver oxygen consumption was decreased (P = .04) with exogenous SRIF and increased (P = .01) with CSH. Net total splanchnic alpha-amino N release and oxygen consumption were decreased (P < .10) with exogenous SRIF, but CSH increased (P < .05) insulin release and oxygen consumption. These data provide initial evidence for a regulatory involvement of SRIF in visceral metabolism in ruminants. PMID- 9374320 TI - Nitrogen metabolism and hormonal responses of steers fed wheat silage and infused with amino acids or casein. AB - Four Holstein steers (159 kg) surgically fitted with abomasal-infusion cannulas were used in a 4 x 4 Latin square study to test amino acid (AA) and casein (CAS) infusions on nitrogen balance and hormonal status of steers consuming vegetative wheat (Triticum aestivum L.) silage (12.3% CP). Treatments were 5-d infusions of 1) water (CONT), 2) arginine (ARG; 13.69 g/d), 3) limiting amino acids (LAA, 13.69 g/d arginine + 10.92 g/d histidine + 28.97 g/d lysine + 10.88 g/d methionine + 16.96 g/d threonine, and 4) Na-CAS (300 g/d). Whole blood was collected for plasma AA, growth hormone (GH), insulin, and IGF-I concentrations. Data were analyzed by ANOVA, and the following orthogonal contrasts were used to separate treatment means: CONT vs ARG; ARG vs LAA; and LAA vs CAS. Urinary N increased (P < .02) for CAS vs LAA. Arginine increased N retention, as did CAS, compared to LAA. Total plasma essential AA were decreased by arginine. Mean plasma insulin concentrations were increased by CAS (P < .034). Arginine increased mean plasma GH levels, but not IGF-I. The CAS treatment increased (P < .015) IGF-I levels, but not GH. These data suggest that performance of steers fed wheat silage was limited by duodenal AA flow and that arginine was the first limiting AA. Casein infusion increased plasma insulin and IGF-I, which would explain the improved growth noted in calves and lambs fed forages supplemented with ruminally undegraded protein. PMID- 9374321 TI - Assessment of postruminal amino acid digestibility of roasted and extruded whole soybeans with the precision-fed rooster assay. AB - The objectives of these studies were to predict the effects of roasting and extrusion temperatures of whole soybeans (SB) on intestinal protein digestibility in cattle. Intestinal digestibility was assessed with a two-stage in vitro or in situ ruminal incubation/precision-fed cecectomized rooster bioassay. In Exp. 1, whole SB (raw SB or SB roasted to 141, 149, or 157 degrees C exit temperature from a commercial roaster and steeped for 30 min) were incubated in strained ruminal fluid and McDougall's buffer (50:50) at 39 degrees C for 16 h. In Exp. 2, SB (ground raw SB or SB extruded at 116, 138, or 160 degrees C) were placed in polyester bags (20 x 30 cm) and suspended in the ventral rumen of steers for 16 h. Lyophilized residue of the in vitro or in situ incubations and samples of raw SB and most extensively heated SB (roasted SB at 157 degrees C or extruded SB at 160 degrees C) for each respective experiment were crop-intubated to cecectomized roosters. Total excreta were collected for 48 h after intubation and lyophilized, and amino acid (AA) concentrations were determined. In Exp. 1, total AA digestibility was 61.6 and 84.5% for unincubated whole raw SB and 157 degrees C roasted SB, respectively, and 66.2, 88.9, 91.3, and 91.6% for in vitro residues of whole raw SB and SB roasted at 141, 149, and 157 degrees C, respectively. Trypsin inhibitor (TI) activity was 20.09, 1.69, 1.54, and 1.84 mg/g fat-free DM for unincubated whole raw SB and 141, 149, and 157 degrees C roasted SB, respectively, and 30.84, 1.01, .90, and .26 mg/g fat-free DM for in vitro residues of whole raw SB, 141, 149, and 157 degrees C roasted SB, respectively. In Exp. 2, total AA digestibility was 68.5 and 87.7% for unincubated ground raw SB and 160 degrees C extruded SB, respectively, and 81.9, 91.3, 89.7, and 89.4% for in situ residues of ground raw SB and 116, 138, and 160 degrees C extruded SB, respectively. Trypsin inhibitor activity was 17.61, 4.89, 4.08, and 1.56 mg/g fat-free DM for unincubated ground raw SB, 116, 138, and 160 degrees C extruded SB, respectively, and 3.62, .59, .55, and .21 mg/g fat-free DM for incubated ground raw SB, 116, 138, and 160 degrees C extruded SB, respectively. Heat treatment by roasting and extrusion improved AA digestibilities of SB, but there were no differences detected among the roasting or extrusion temperatures. Ruminal fermentation did not eliminate the negative effects of TI activity on intestinal digestibility of AA in whole SB but did reduce TI activity in ground SB. PMID- 9374322 TI - Effects of dipeptides administered to a perfused area of the skin in Angora goats. AB - The effect of dipeptide infusion on mohair growth of Angora goats was investigated using a skin perfusion technique. Six Angora wethers (average BW 32 +/- 2 kg) were implanted bilaterally with silicon catheters into the superficial branches of the deep circumflex iliac artery and to the deep circumflex iliac vein. For the first 14 d of the experiment, animals received infusions into the deep circumflex iliac arteries of either a mixture of Met-Leu and Lys-Leu (one side) or saline (other side). Infusion rates of amino acids were .72 mg/h Met-Leu and .72 mg/h Lys-Leu. The area of skin supplied by the deep circumflex iliac artery was approximately 300 cm2. An area of 150 cm2 within the perfused region was used to determine mohair growth. Two weeks after the cessation of infusions, perfused areas were shorn, and greasy and clean mohair production, staple length, and diameter were determined. Greasy and clean mohair production from the perfused region were increased by dipeptide infusion compared to the side infused with saline (1.91 vs 1.66 g, P < .05 and 1.56 vs 1.31 g, P < .04, respectively). No significant changes were observed in mohair diameter; however, staple length tended to increase as a result of dipeptide infusion (18.0 vs 16.1, P < .1). Decreased concentrations of Met, Cys, Lys, Phe, Val, Ileu, Leu, and Arg were observed in the venous blood taken from the deep circumflex iliac vein on the side infused with the amino acid mixture compared with blood taken from the saline side (P < .05). There were no treatment differences in triiodothyronine, thyroxine, or insulin concentrations in venous blood taken from the deep circumflex iliac vein. Direct skin infusion with dipeptide may have resulted in mobilization of amino acids for increased protein synthesis, or the infused dipeptides may have acted as growth promoters stimulating skin amino acid uptake and protein synthesis. PMID- 9374323 TI - Long-term effects of consumption of low-copper diets with or without supplemental molybdenum on copper status, performance, and carcass characteristics of cattle. AB - We used 42 Angus bull calves (7 mo of age) to determine long-term effects of low Cu diets with or without supplemental Mo on performance, carcass characteristics, and Cu status. Twenty-two bulls were injected with 90 mg of Cu 28 d before weaning. After weaning, injected steers were fed a diet supplemented with 7.5 mg of Cu/kg of DM; control steers received no supplemental Cu. At the end of the 40 d receiving phase, supplemental Cu was reduced to 5 mg/kg of DM. One half of the steers in each group were fed 5 mg of supplemental Mo/kg of DM following the receiving phase. The growing phase lasted 196 d. Steers were then switched to a high concentrate finishing diet for 49 d. Copper injection increased (P < .01) plasma Cu concentrations at weaning, and Cu-supplemented steers had greater (P < .05) plasma Cu, ceruloplasmin, superoxide dismutase activity (SOD), and liver Cu at the beginning of the growing phase. Supplemental Mo depressed plasma Cu, ceruloplasmin, and SOD during the growing and finishing phases in non-Cu supplemented but not in Cu-supplemented steers. Copper supplementation increased DMI during the receiving (P < .05) and growing (P < .08) phases and increased (P < .08) ADG and gain:feed ratios during the finishing phase. Steers fed supplemental Cu produced carcasses with less (P < .06) backfat and slightly larger (P < .09) rib eye areas. The results of this experiment suggest that dietary Cu concentrations may alter cattle performance and carcass characteristics. PMID- 9374324 TI - Effect of amino acid supplementation on whole-body protein turnover in Holstein steers. AB - We used the [15N]glycine single-dose urea end-product technique to measure whole body protein turnover in six Holstein steers (250 +/- 18 kg). Steers were implanted with Revalor-S and continuously infused abomasally with water (4 L/d) or amino acids (AA; in 4 L/d water) in a crossover experiment (two 14-d periods). The AA infusion contained the following (g/d): lysine (5.3), methionine (3.3), threonine (3.2), tryptophan (1.0), histidine (2.1), and arginine (5.5). Steers were fed a diet containing 85% rolled corn, 10% prairie hay, and 1.1% urea (DM basis) at 2.16% of body weight. Nitrogen retention tended (P = .15) to increase with AA infusion, from 27.9 to 32.9 g N/d. Amino acid infusion numerically increased whole-body protein turnover from 168.6 to 183.2 g N/d, protein synthesis from 152.6 to 169.3 g N/ d, and protein degradation from 124.7 to 136.4 g N/d. Enhanced protein accretion may have resulted from a larger increase in protein synthesis than in degradation. The tendency for increased N retention is interpreted to suggest that the implanted, lightweight Holstein steers fed a corn urea diet in our study were able to respond to AA supplementation, suggesting that at least one of the infused AA was limiting in the basal diet. Protein turnover data suggest that cattle, like other animals, may increase protein synthesis and protein degradation in response to supplementation with limiting AA. The [15N]glycine single-dose urea end-product technique for measuring whole body protein turnover in cattle may be useful. PMID- 9374325 TI - Zinc repletion with organic or inorganic forms of zinc and protein turnover in marginally zinc-deficient calves. AB - We conducted two experiments using marginally Zn-deficient (-Zn) calves to determine which supplemental chemical form of Zn would most rapidly reverse certain Zn deficiency signs and to determine whether a change in protein turnover had occurred in Zn deficiency. In Exp. 1, 40 crossbred beef heifers were allocated by BW to four groups. The control group received 23 mg Zn/kg diet DM from ZnSO4 supplemented to the -Zn diet (17 mg Zn/kg diet DM). The three other groups received the -Zn diet. After 21 d, based on a decreased (P < .05) feed efficiency, they were deemed -Zn. Cell-mediated immune (CMI) response to phytohemagglutinin (PHA) was reduced (P < .05) but plasma and liver Zn were unaffected in the -Zn calves. Zinc was repleted by feeding iso-Zn amounts (23 mg Zn/kg diet DM) from Zn lysine, Zn methionine, or ZnSO4. At 8 h after injection of PHA, control CMI response values were similar to Zn Methionine, and Zn lysine was lower (P < .05). In Exp. 2, 10 Holstein steers were allocated by BW to two groups. One group received the -Zn diet, and the other received the +Zn diet. Urine collections were obtained from both groups of calves when the -Zn calves showed a decrease (P < .05) in feed efficiency relative to the controls and when they were repleted with 23 mg Zn/kg diet DM from ZnSO4 and their feed efficiency had returned to that of the controls. Urinary 3-methylhistidine indicated that Zn calves had less (P < .05) daily protein degradation than the controls. Refeeding Zn to the -Zn group did not change BW or daily protein degradation. Results indicated that a marginal Zn deficiency decreased fractional accretion rate, increased (P < .05) urine excretion, and tended to increase (P < .19) Na and decrease (P < .12) K concentrations in the urine. PMID- 9374326 TI - Chronic and transitional regulation of gluconeogenesis and glyconeogenesis by insulin and glucagon in neonatal calf hepatocytes. AB - Milk-fed calves were used as a source of hepatocytes to establish monlayers to test the effects of chronic (41 h) incubation with no hormone, 100 nM insulin, or 100 nM glucagon on gluconeogenesis (glucose retained as glycogen plus glucose released into the medium) from 2.5 mM [2-(14)C]propionate and 2.0 mM [U 14C]lactate (1.0 mM lactate plus 1.0 mM pyruvate) during a subsequent 3-h (acute) incubation. Media for acute incubations contained no hormone, 0 or 10 nM insulin, or 0, 1, 10, or 100 mM glucagon. Chronic glucagon increased gluconeogenesis from propionate and glyconeogenesis from propionate and lactate compared with chronic exposure to medium with no hormone. A chronic glucagon x acute hormone interaction was manifested as an augmented response to acute glucagon on gluconeogenesis from propionate; a similar potentiation was not evident for gluconeogenesis from lactate. The concentration of glucagon required to acutely stimulate gluconeogenesis was increased by prior incubation with glucagon. Acute glucagon decreased the flux of glucose retained as glycogen regardless of chronic hormone treatment. Chronic incubation with insulin diminished the stimulatory effects of glucagon on gluconeogenesis from lactate. Chronic incubation with insulin did not alter the sensitivity or responsiveness at acute glucagon of gluconeogenesis from propionate. The data demonstrate persisting changes that favor increased basal gluconeogenesis from propionate with chronically elevated glucagon coupled to an increased capacity to respond acutely to glucagon and opposing chronic actions of insulin on lactate metabolism. These data suggest that insulin and glucagon target separate pathways that are unique to metabolism of propionate and lactate. PMID- 9374327 TI - New research developments increase therapeutic options for thyroid cancer and bone pain palliation. PMID- 9374329 TI - Continuous ambulatory radionuclide monitoring of left ventricular function: effect of body position during ergometer exercise. AB - We assessed the reliability of a continuous ambulatory radionuclide monitoring system (the VEST system, Capintec, Inc., Ramsey, NJ) for measurement of left ventricular performance during exercise in the upright and supine positions. METHODS: Sixteen healthy male volunteers (aged 32-46 yr; mean age 37 +/- 4 yr) were studied. All volunteers underwent ergometer exercise testing in both the upright and supine positions, and left ventricular performance was determined with the VEST system. RESULTS: The resting heart rate, systolic blood pressure, pressure rate product, relative end-diastolic volume, relative end-systolic volume and left ventricular ejection fraction (LVEF) all showed no differences between the upright and supine positions. At peak exercise, the heart rate, systolic blood pressure and pressure rate product showed no differences between the upright and supine positions. In the upright position at peak exercise the relative end-diastolic volume was increased (83% +/- 9% to 91% +/- 11%, p < 0.001); the relative end-systolic volume remained unchanged (34% +/- 3% to 33% +/ 15%), and LVEF was significantly increased from 58% +/- 6% to 66% +/- 11% (p < 0.01). In the supine position at peak exercise, the relative end-diastolic volume remained unchanged (85% +/- 5 to 83% +/- 7%), the relative end-systolic volume was increased (35% +/- 5% to 43% +/- 13%, p < 0.01), and LVEF was decreased from 58% +/- 5% to 48% +/- 17% (p < 0.01). These results indicated inferior data collection by the VEST system in the supine position. CONCLUSION: Since the detector of the VEST system may be too small, the data collection is impaired during exercise in the supine position by shifting the heart with deep respiration. The VEST system is very useful for determining left ventricular performance when applied in the sitting or upright position. However, in the supine position during exercise, the use of the VEST system should be avoided because it might indicate an artifactual deterioration of left ventricular performance. PMID- 9374330 TI - Seeing is believing. PMID- 9374331 TI - Comparison between technetium-99m-sestamibi and hydrogen-3-daunomycin myocardial cellular retention in vitro. AB - This study was undertaken to verify whether 99mTc-sestamibi uptake parallels that of 3H-daunomycin in cells treated with multidrug resistance (MDR) reversing agents. Since we have detected in a previous work a moderate typical MDR phenotype in rat cardiac cells, a model of cultured myocardial cells was used. METHODS: Newborn-rat cultured myocardial cells were incubated 120 min with the MDR-reversing agent verapamil 50 microM, PSC833 1 microM or S9788 10 microM alone or in combination, and the cellular retention of 3H-daunomycin and 99mTc sestamibi was counted. RESULTS: Hydrogen-3-daunomycin cellular accumulation was never modified by more than 15% when compared to control values, while 99mTc sestamibi decreased to 75% +/- 32% (m +/- s.d.) of controls in the presence of S9788 and to 44% +/- 19% when S9788 was associated with verapamil. CONCLUSION: The variations of 99mTc-sestamibi and 3H-daunomycin cellular accumulation induced by MDR-reversing agents in cultured myocardial cells can be dramatically different. While some MDR-reversing agents can significantly increase the 3H daunomycin retention in cardiac cells, they have unexpected effects on that of 99mTc-sestamibi. PMID- 9374332 TI - Cardiac sympathetic neuropathy and effects of aldose reductase inhibitor in streptozotocin-induced diabetic rats. AB - Cardiac autonomic neuropathy can be a cause of sudden death in patients with diabetes mellitus. Clinical evaluation methods for diabetic cardiac sympathetic neuropathy have not been established. Using 125I-metaiodobenzylguanidine (MIBG) and streptozotocin (STZ)-induced diabetic rats, we evaluated cardiac sympathetic neuropathy and the effects of aldose reductase inhibitor (ARI). METHODS: Myocardial MIBG uptake was measured 4 hr after injection in the following groups: control rats, rats treated with insulin or ARI (epalrestat, 100 mg/kg/day) from immediately to 4 wk after STZ injection and rats treated with insulin or ARI from 4-8 wk. Myocardial MIBG distribution and norepinephrine content were evaluated in the control and diabetic rats with or without ARI therapy started immediately after STZ injection. RESULTS: Myocardial MIBG uptake was significantly lower in diabetic rats than in control rats; the reduction was marked in the subendocardial myocardium. Myocardial norepinephrine content was increased significantly in diabetic rats compared with control rats. Decreased MIBG uptake and increased norepinephrine content in diabetic myocardium were completely prevented by insulin therapy started immediately after STZ injection and partially, but significantly, by ARI administered from immediately after STZ injection. Heterogeneous MIBG distribution also disappeared with the ARI therapy. In contrast, diabetic rats treated with insulin or ARI therapy started 4 wk after STZ injection showed no improvement in MIBG uptake. CONCLUSION: These results suggest that MIBG abnormalities observed in diabetic rats may reflect diabetic cardiac sympathetic neuropathy independently of cardiomyopathy, nephropathy or coronary heart disease secondary to diabetes and that MIBG imaging may be useful for clinical assessment of cardiac sympathetic neuropathy. PMID- 9374333 TI - Reversed ventilation-perfusion mismatch involving a pediatric patient in congestive heart failure. AB - Over the past 13 yr, at least 11 specific etiologies of reversed ventilation perfusion mismatch have been reported in the literature. In this article, a case of reversed ventilation-perfusion mismatch involving a patient in congestive heart failure receiving dobutamine and milrinone therapy is presented. A brief review of the topic of reversed ventilation-perfusion mismatch is presented. PMID- 9374334 TI - One-year effect of myocardial revascularization on resting left ventricular function and regional thallium uptake in chronic CAD. AB - It is still unclear whether in patients with chronic coronary artery disease (CAD) the improvements in myocardial perfusion and left ventricular (LV) function induced by revascularization persist in the long run. This study was planned to evaluate the 1-yr effects of successful revascularization on myocardial perfusion and LV function in patients with CAD and to assess the accuracy of thallium imaging in the prediction of functional recovery 1 yr after revascularization. METHODS: Thirty-eight patients with chronic CAD who were revascularized (experimental group) underwent, while off drugs, 201Tl tomography, two dimensional echocardiography and radionuclide angiography before and after a 1-yr follow-up. Twenty-nine patients with similar characteristics who were not revascularized (control group) and completed the 1-yr follow-up were also studied. Regional thallium activity was quantitatively measured in 13 segments per patient. Systolic function was assessed by echocardiography in corresponding segments. RESULTS: In the experimental group, at baseline, on the basis of regional LV function and thallium uptake, 276 segments were normal, 169 dysfunctional-viable and 49 nonviable. After revascularization, the majority (75%) of the dysfunctional-viable segments at baseline showed functional recovery at follow-up, whereas the majority (81%) of the nonviable segments at baseline did not. Simultaneously, LV ejection fraction increased 4 wk after revascularization (from 39% +/- 9% to 42% +/- 10%, p < 0.01) and remained unchanged after 1-yr (43% +/- 8%, p < 0.01 versus baseline study). LV wall-motion score index after 1 yr was reduced (from 1.68 +/- 0.4 to 1.42 +/- 0.3, p < 0.001) as compared with baseline. On the contrary, in the control group, no change in myocardial perfusion and LV function was detected after the 1-yr follow-up. CONCLUSION: In patients with chronic CAD, successful coronary revascularization induces a stable improvement in myocardial perfusion and LV function, which is still detectable after a 1-yr follow-up. Furthermore, preserved thallium uptake in dysfunctional regions is predictive of functional recovery after revascularization. PMID- 9374335 TI - Benzodiazepine receptors in chronic cerebrovascular disease: comparison with blood flow and metabolism. AB - The brain benzodiazepine (BZD) receptor distribution in patients with chronic cerebrovascular disease was assessed with 123I-iomazenil (IMZ) SPECT, and the findings were compared with the data for the cerebral blood flow (CBF) and cerebral metabolism. METHODS: We examined nine patients with chronic cerebrovascular diseases, six patients with cerebral infarction and three with moyamoya disease. Iodine-123-IMZ SPECT images were obtained for 15 min, 3 hr after the administration of 167 or 222 MBq 123I-IMZ. In seven patients, the CBF and oxygen metabolism were measured by the 50 steady-state method. In two patients, the CBF and glucose metabolism were measured by 99mTc-HMPAO SPECT and 18F-fluoro-2-deoxy-D-glucose-PET, respectively. The brain was initially classified into 18 regions, and abnormalities in the BZD receptor distribution, CBF and cerebral metabolism were visually evaluated. The count ratio of lesion-to contralateral normal region (L-to-C ratio) was then used for comparison. RESULTS: In the core of the infarct, the 123I-IMZ uptake decreased (L-to-C ratios of the blood flow 0.42 +/- 0.26; metabolism 0.45 +/- 0.24; and 123I-IMZ uptake 0.46 +/- 0.14). In the peri-infarct region, the 123I-IMZ uptake slightly decreased (L-to-C ratios of 0.81, 0.82 and 0.89, respectively). In the region of misery perfusion, the 123I-IMZ uptake was preserved (L-to-C ratios of 0.73, 1.07 and 1.02, respectively). In the remote deafferentiated areas in the ipsilateral cerebrum, the 123I-IMZ uptake was preserved (L-to-C ratios of 0.76 +/- 0.10, 0.75 +/- 0.04 and 0.98 +/- 0.05, respectively). In the remote areas in the contralateral cerebellum, the 123I-IMZ uptake was preserved (L-to-C ratios of 0.84 +/- 0.08, 0.85 +/- 0.04 and 0.94 +/- 0.05, respectively). CONCLUSION: The BZD receptor distribution, as measured by 123I-IMZ SPECT, is not considered to reflect neuronal function, but it may reflect neuronal cell viability. Iodine-123-IMZ SPECT may, therefore, hold promise as a potential probe for neuronal damage. PMID- 9374336 TI - Quantification of regional cerebral blood flow with continuous infusion of technetium-99m-ethyl cysteinate dimer. AB - We propose a new method to quantify regional cerebral blood flow (rCBF) with continuous infusion of 99mTc-ethyl cysteinate dimer (ECD) and dynamic SPECT. METHODS: Thirteen subjects were studied. Seven subjects had SPECT and PET studies, and the other six subjects were involved in the measurement of blood clearance of 99mTc-ECD. During constant infusion of 99mTc-ECD (740 MBq) over 10 min, dynamic SPECT scans were obtained every 1 min by means of a triple-head rotating SPECT camera. Intermittent arterial blood sampling with octanol extraction was performed every 1 min to estimate the arterial input function. Influx constant (Ku) obtained by Gjedde-Patlak graphical plot method was compared with rCBF measured by PET using 15O CO2 steady state method. In order to simplify the procedure, arterial input function in each subject was estimated by calibration of the arterial blood sampled at the end of the scan to the standard arterial input function estimated from the blood clearance rate in six subjects. RESULTS: Ku was linearly correlated with rCBF (Ku = 0.09 + 0.62 rCBF, r = 0.85, p < 0.05). Ku calculated with the estimated input function (Ku') and rCBF also demonstrated a linear relationship (Ku' = 0.05 + 0.65 rCBF, r = 0.84, p < 0.05). CONCLUSION: The proposed method with one-point arterial sampling is a simple, clinically feasible tool for quantitative measurement of rCBF with 99mTc-ECD. PMID- 9374337 TI - Imaging and quantitation of dopamine transporters with iodine-123-IPT in normal and Parkinson's disease subjects. AB - Iodine-123-N-(3-iodopropene-2-yl)-2beta-carbomethoxy-3beta-( 4-chlorophenyl) tropane (123I-IPT) is a new dopamine transporter ligand that selectively binds the dopamine reuptake sites. Transporter concentrations have been known to decrease in Parkinson's disease patients. The purpose of this study was to evaluate the usefulness of IPT as an imaging agent for measuring changes in transporter concentrations in Parkinson's disease. METHODS: IPT labeled with 6.78 +/- 0.67 mCi 123I was injected intravenously as a bolus into eight normal controls (mean age 41 +/- 12 yr) and 17 Parkinson's disease patients (mean age 55 +/- 9 yr). Dynamic SPECT scans of the brain were then performed for 5 min each over 120 min on a triple-headed gamma camera equipped with medium-energy collimators. Regions of interest were drawn on the middle set of the image at the level of the basal ganglia (BG) for each subject. Time-activity curves were generated for the left BG, right BG and occipital cortex (OCC). The empirical ratios between BG-OCC and OCC, which represent specific-to-nonspecific binding ratios, were computed at various time points. The statistical parameter k3/k4 was estimated by two methods: a variation of the graphic method that derives the ratio of ligand distribution volumes (R[V]) and the area ratio method (R[A]), in which the ratio is calculated from the areas under the specific and nonspecific binding activity curves. RESULTS: The mean (BG-OCC)/OCC ratio for normal controls (3.07 +/- 0.73) was significantly higher than that for Parkinson's disease patients at 115 min (1.10 +/- 0.56) (p = 2.76 x 10[-5]). The mean R(V) and R(A) for normal controls were 2.06 +/- 0.27 and 1.50 +/- 0.15, respectively. The mean R(V) and R(A) for Parkinson's disease patients were 0.78 +/- 0.31 and 0.65 +/- 0.24, respectively. Both R(V) and R(A) for normal controls were significantly higher than those for Parkinson's disease patients (p values for R(V) and R(A) were 1.91 x 10(-8) and 3.46 x 10(-10), respectively). The R(V) has linear relationships with both R(A) and (BG-OCC)/OCC ratio at 115 min. The R(V) has a higher correlation (r = 0.99) with R(A) than it does with (BG-OCC)/OCC (r = 0.93). CONCLUSION: The R(V), R(A) and (BG-OCC)/OCC for Parkinson's disease patients were clearly separated from those of normal controls, and they may be useful outcome measures for clinical diagnosis. The simplest (BG-OCC)/OCC ratio, requiring a single late time point, could be useful in clinical situations, whereas R(V) or R(A) is preferred when the dynamic data are available. The findings suggest that 123I-IPT is a useful tracer for diagnosing Parkinson's disease and studying dopamine reuptake sites. PMID- 9374339 TI - Fluorine-18-FDG evaluation of crossed cerebellar diaschisis in head injury. AB - This study investigates the phenomenon of crossed cerebellar diaschisis in head injury patients. METHODS: We visually compared fluorine-18-fluorodeoxyglucose (FDG)-PET images to radiograph computed tomography or magnetic resonance images in 19 patients with head injury. RESULTS: We found that of 68 focal unilateral lesions, 40% were associated with contralateral cerebellar hypometabolism and 19% were associated with ipsilateral cerebellar hypometabolism. Of supratentorial, extraparenchymal lesions (n = 20), 45% were associated with contralateral cerebellar hypometabolism, whereas 15% had ipsilateral cerebellar hypometabolism. Intraparenchymal lesions were associated with contralateral cerebellar hypometabolism in 38% of the patients and with ipsilateral cerebellar hypometabolism in 21% of the patients. Of the cortical lesions that were the patients' most severe injury, 69% were associated with contralateral cerebellar hypometabolism, whereas only 8% were associated with ipsilateral cerebellar hypometabolism. In patients with focal supratentorial lesions alone, 50% of all focal lesions were associated with contralateral cerebellar hypometabolism and 13% had ipsilateral hypometabolism. Of patients with both focal and diffuse brain injuries, 27% of the focal lesions had contralateral cerebellar hypometabolism and 27% had ipsilateral cerebellar hypometabolism to the most severe focal injury. CONCLUSION: Crossed cerebellar diaschisis is seen more often in patients with focal cortical or extraparenchymal injuries and is not seen in patients with multiple or diffuse brain injuries. Furthermore, this predominance is more pronounced with lesions of the greatest severity. PMID- 9374338 TI - Iodine-123-epidepride-SPECT: studies in Parkinson's disease, multiple system atrophy and Huntington's disease. AB - Epidepride is a benzamide derivative with very high affinity for D2 receptors, which, in its [123I]-labeled form, can be used for SPECT. The aim of this study was to evaluate the usefulness and accuracy of [123I]epidepride-SPECT for the differential diagnosis of movement disorders. METHODS: SPECT imaging with a triple-headed scintillation camera was performed in 9 patients with Parkinson's disease, 9 patients with probable multiple system atrophy (MSA), 1 patient with progressive supranuclear palsy, 16 patients with Huntington's disease (HD) and 14 controls, 3 hr after the intravenous injection of 3.7 +/- 1.3 mCi of [123I]epidepride. The striatum-to-cerebellum ratio - 1, reflecting the specific to-nondisplaceable binding ratio, was used as a semiquantitative measure of D2 receptor binding. RESULTS: Kinetic studies showed peak striatal uptake about 3 hr postinjection and a slow decline thereafter. The striatum-to-cerebellum ratio - 1 was significantly reduced in MSA (11.8 +/- 3.9, compared to controls, 19.0 +/- 6.3; p < 0.01) and in patients with HD (8.8 +/- 3.2; p < 0.00005) but normal in Parkinson's disease (15.8 +/- 3.6; not significant). A high interindividual variation of specific striatal epidepride binding (striatum - cerebellum; cpm/mCi x kg) was found in controls and in all patient groups. The interindividual variation of striatum-to-cerebellum ratios was lower but still considerable. In half of the MSA patients, the specific-to-nondisplaceable binding ratio fell within the range of controls. The use of various cortical reference regions did not improve discrimination between MSA and controls or Parkinson's disease patients, respectively. The discrimination of HD patients from controls was better, with overlap in only two cases. In one HD patient, calculation of the striatum-to-cerebellum ratio was almost impossible due to extremely low nonspecific binding. Possible explanations for the large variation of the ratios, resulting in an overlap between controls and different patient groups, are very low counting rates in the reference region and the fact that a transient binding equilibrium may not be achieved after bolus injection of epidepride. CONCLUSION: Epidepride appears to be a useful SPECT ligand for studying dopamine D2 receptors. However, its markedly higher specific-to-nondisplaceable binding ratio in comparison to those of iodobenzamide or other D2 ligands did not result in a better discrimination between different basal ganglia disorders. The calculation of plasma input curves and volumes of distribution might improve the accuracy of [123I]epidepride-SPECT. PMID- 9374340 TI - SPECT image analysis using statistical parametric mapping: comparison of technetium-99m-HMPAO and technetium-99m-ECD. AB - The goal of this study was to examine the apparent differences in regional cerebral blood flow (rCBF) between two groups of normal individuals who received either of the two tracers, 99mTc-D,L-hexamethylpropylene amine oxide (99mTc HMPAO, or exametazime) or 99mTc-ethylene-dicysteine diethylester (99mTc-ECD, or bicisate). METHODS: Individuals were screened for drug use, head injury, medication status and other psychiatric and medical illnesses. The two groups were matched for age, sex and race. SPECT measurement of brain perfusion was performed in 35 individuals who received 99mTc-HMPAO and in 55 who received 99mTc ECD. Subsequent analysis of these scans was done using computer software including Statistical Parametric Mapping and Analyze. Images were intensity thresholded and spatially normalized to a standardized stereotactic (Talairach) space. This allowed for the objective, quantitative analysis of these data, demonstrating the extent and magnitude of rCBF changes. RESULTS: Our results showed significant changes between these two groups of normal individuals, presumably due to differences in pharmacokinetics between the two radiolabeled tracers. Specifically, large areas of the parietal, occipital and superior temporal cortices were significantly lower in the 99mTc-HMPAO group than in the 99mTc-ECD group. Increases were seen in the subcortical nuclei, parts of the brain stem, hippocampus and small areas of the cerebellum in the 99mTc-HMPAO group as compared to the 99mTc-ECD group. CONCLUSION: We present a method of image analysis to semiquantitatively measure rCBF in SPECT images and the changes seen due to differences between the two radiotracers. PMID- 9374341 TI - Longer occupancy of opioid receptors by nalmefene compared to naloxone as measured in vivo by a dual-detector system. AB - Surgical procedures usually involve the administration of narcotic drugs as anesthetics or adjuvants. To reverse the effects of anesthesia, opioid antagonists such as naloxone are commonly used. Due to its short lasting effects, patients receiving naloxone must be monitored carefully. Nalmefene, a pure opiate antagonist with a longer duration of action than naloxone, has shown promise in the reversal of opioid anesthesia. METHODS: A simple dual-detector positron radiation detector system and [11C]carfentanil were used to compare the duration of blockade of cerebral mu opioid receptors by naloxone and nalmefene in eight normal volunteers. Carbon-11-carfentanil brain kinetics were monitored for 5 min and 2, 4, 8 and 24 hr after the administration of either nalmefene (1 mg or 1 microg/kg) or naloxone (2 mg or 2 microg/kg). Blood samples were obtained at the same times for plasma determinations. RESULTS: Clearance half-times from opioid receptors were 28.7 +/- 5.9 hr for 1 mg of nalmefene and 2.0 +/- 1.6 hr for 2 mg of naloxone. Brain clearance times were about 21.1 and 3.4 times slower than plasma clearance times for nalmefene and naloxone, respectively. CONCLUSION: These findings suggest that the prolonged effects of nalmefene are related to the slow dissociation of nalmefene from opioid receptors, which are not reflected in the plasma curve. This longer blockade of opioid receptors by nalmefene represents an advantage in the clinical management of postsurgical reversal of narcotic anesthesia and opioid side effects as well as the reversal of opioid overdose. PMID- 9374342 TI - Metabolism of technetium-99m-L,L-ethyl cysteinate dimer in rat and cynomolgus monkey tissue. AB - Technetium-99m-L,L-ethyl cysteinate dimer (99mTc-ECD) is thought to be hydrolyzed in the brain by an enzyme and to be trapped as a hydrophilic product. We investigated the characteristics of the enzymatic system that metabolizes 99mTc ECD. METHODS: In 50 mM phosphate buffer (pH 7.4), 99mTc-ECD was incubated with various concentrations of homogenates of rat tissues (blood, liver and brain) or cynomolgus monkey tissues (blood, liver, cerebral gray matter, cerebral white matter and cerebellar gray matter), and the metabolic rates were assessed. Inhibition studies were performed using diisopropyl fluorophosphate, eserine and p-chloromercuribenzoate as inhibitors. The metabolic rates in the brain homogenates of rat and monkey were measured at various levels of pH, ranging from 6.6 to 7.6. Technetium-99m-L,L-ethyl cysteinate dimer metabolism was also examined in the presence of purified enzymes. RESULTS: In both species, the metabolic rate was high in liver tissue, intermediate in brain tissue and low in blood. The rate in cerebral gray matter of cynomolgus monkey was higher than those in rat brain, monkey cerebral white matter and monkey cerebellar gray matter. All substances used as inhibitors depressed 99mTc-ECD metabolism, and the response was different among tissues. Reduction in pH induced slight decreases in metabolic rate. Hydrophilic conversion of 99mTc-ECD was observed after incubation with porcine liver carboxylesterase. CONCLUSION: These results support the hypothesis that the hydrophilic conversion of 99mTc-ECD is mediated by enzymes. It is also suggested that various enzymes catalyze the hydrolysis of 99mTc-ECD and that the enzymatic system that metabolizes 99mTc-ECD is different between tissues and between species. PMID- 9374343 TI - Imaging nicotinic acetylcholine receptors with fluorine-18-FPH, an epibatidine analog. AB - Nicotinic acetylcholine receptors (nAChRs) have been implicated in a variety of central processes, such as learning and memory and analgesia. These receptors also mediate the reinforcing properties of nicotine in tobacco products and are increased in postmortem samples of brains of smokers. On the other hand, brains of individuals who have died from dementia of the Alzheimer type show abnormally low densities of nAChRs. In this study, the distribution and kinetics of [(+/-) exo-2-(2-[18F] fluoro-5-pyridyl)-7-azabicyclo[2.2.1]heptane (18F-FPH), a high affinity nAChR agonist, was evaluated in a baboon using PET. METHODS: After intravenous injection of 5 mCi [185 MBq] 18F-FPH into a 25-kg anesthetized baboon, sequential quantitative tomographic data were acquired over a period of 150 min. Regions of interest were placed and time-activity curves were generated. Brain kinetics of the radiotracer were calculated, and the in vivo regional binding in the baboon brain was compared with the known in vitro regional distribution of nAChRs in the rat and human brain. RESULTS: Brain activity reached a plateau within 60 min after injection of the tracer, and the binding was reversible. Elimination of 18F-FPH was relatively rapid from the cerebellum (clearance t[1/2] = 3 hr), intermediate from the hypothalamus/midbrain (t[1/2] = 7 hr) and slow from the thalamus (t[1/2] = 16 hr). Radioactivity due to 18F-FPH at 130 min postinjection was highest in the thalamus and hypothalamus/midbrain, intermediate in the neocortex and hippocampus and lowest in the cerebellum. Subcutaneous injection of 1 mg/kg cytisine 45 min after injection of the radiotracer reduced brain activity at 130 min by 67%, 64%, 56% and 52% of control values in the thalamus, hypothalamus/midbrain, hippocampus and cerebellum, respectively. The regional binding of 18F-FPH at 130 min was highly correlated with the known densities of nAChR measured in vitro in human (r = 0.81) and rat brain (r = 0.90). CONCLUSION: These results demonstrate the feasibility of imaging nAChRs in vivo. Fluorine-18-FPH appears to be a suitable tracer to study nAChRs in the human brain. PMID- 9374344 TI - Technetium-99m(V)-DMSA and thallium-201 in brain tumor imaging: correlation with histology and malignant grade. AB - This study was performed to compare imaging ability between pentavalent 99mTc DMSA and 201TlCl in primary and metastatic brain tumors and to evaluate the relationship between retention and histologic malignancy. METHODS: Patients with a brain tumor were selected by MRI and/or CT. Dynamic, early and delayed static SPECT images of the brain were obtained immediately, 30 min and 3 hr after intravenous administration of approximately 555 MBq 99mTc(V)-DMSA and 111 MBq 201Tl-Cl, respectively. Both studies were performed on separate days within a week. Uptake ratios, retention ratio and retention index were calculated and compared with tumor histology and malignancy grade. RESULTS: One-hundred six studies were performed on 100 patients and 118 lesions were demonstrated: 16 glioblastomas, 13 anaplastic astrocytomas (Grade III), 19 astrocytomas (Grade II), 29 meningiomas, 11 schwannomas and 14 metastases. Approximately 93% and 88%, respectively, of primary and metastatic brain tumors were demonstrated by 99mTc(V)-DMSA and 201TlCl. The early uptake ratios were closely related to the tumor vascularity, but had no statistically significant difference in the tumor histology or histologic malignancy on either radiopharmaceuticals. The delayed uptake ratio, retention ratio and retention index were higher in malignant tumors than benign ones on 99mTc(V)-DMSA, however, there was no statistically significant difference between benign and malignant tumors on 201TlCl. CONCLUSION: Technetium-99m(V)-DMSA washout from the tumor was highly dependent upon its histology and histologic malignancy. The delayed uptake ratio, retention ratio and retention index significantly reflected tumor histology and clearly distinguished between benign and malignant tumors with a statistically significant difference. There was no statistically significant difference in 201TlCl uptake or washout among the brain tumors. Technetium-99m-DMSA is superior to 201TlCl in imaging quality, sensitivity to brain tumors and specificity for differentiating benign tumors from malignant ones. These results could suggest the clinical utility of 99mTc(V)-DMSA in imaging primary and metastatic brain tumors and differentiating their histological malignancy grade noninvasively. PMID- 9374345 TI - Prediction of myelotoxicity using semi-quantitative marrow image scores. AB - Marrow radiation with resultant myelosuppression is usually dose-limiting in radioimmunotherapy (RIT). This study evaluated the relationship between a semiquantitative score of radiolabeled antibody marrow uptake obtained by imaging and subsequent decrease in peripheral blood cell counts in a patient population in whom marrow malignancy is common. METHODS: Semiquantitative scores were assigned to lumbar marrow images of 18 patients acquired 0, 6, 24 and 48 hr after the first therapy dose of 131I-Lym-1. Scores were adjusted for injected dose (GBq) and body surface area (m2), and correlated with post-therapy blood counts. A well-defined scale, where 0 and 4 represented least to highest marrow uptake when compared to background, was used to assign marrow image scores. Injected doses of 131I-Lym-1 ranged from 1.1-8.2 GBq (29-222 mCi). RESULTS: Linear regression of summed marrow scores (0-24 hr after injection) versus decrease in cell counts produced correlation coefficients of 0.76, 0.44, 0.58 and 0.46 for platelets, granulocytes, white blood cells (WBC) and hematocrit, respectively. Scores for individual and other combinations of images obtained immediately up to 24 hr after injection were also predictive. PMID- 9374346 TI - Predicting myelotoxicity in radioimmunotherapy: what does dosimetry contribute? PMID- 9374347 TI - Immunoscintigraphy of the bone marrow: normal uptake values of technetium-99m labeled monoclonal antigranulocyte antibodies. AB - The aim of our study was to determine the normal range of the 99mTc-labeled anti NCA 95 antigranulocyte antibody (AGAb) uptake in the bone marrow using the sacroiliac-to-background uptake ratio in the posterior view. METHODS: We made 169 planar bone marrow scans on 162 patients who were each injected with 555 MBq AGAb. Fifty patients with the diagnosis of infection/pyrexia of unknown origin (PUO) and with completely normal bone marrow scintigraphy were defined as the normal group. Uptake ratios were calculated drawing irregular regions of interest around the sacroiliac and a background area, respectively. RESULTS: The normal group revealed a mean uptake ratio of 7.3 +/- 2.3 (range 4.4-12.6). Similar uptake ratios were obtained in patients with the primary diagnosis of infection/PUO and bone marrow extension (7.4 +/- 2.2, range 4.2-11.7), suggesting that the bone marrow reacts on infection primarily by extension into the periphery, without any significant increase of the activity of the central hemopoietic/granulopoietic bone marrow. Mean uptake ratios also were not significantly different in patients with normal bone marrow scintigraphy and the primary diagnosis of solid malignant tumors, lymphomas and plasmacytomas, and in patients with focal lesions visible on bone marrow scintigraphy (soft tissue inflammation or cold lesions in the bone marrow but with normal sacroiliac regions). Mean uptake ratios in the normal group were significantly age related, amounting to 8.5 +/- 1.8, 7.5 +/- 1.9 and 6.1 +/- 2.0 in patients younger than 40 yr, between 40 and 59 yr, and 60 yr or older, respectively (p = 0.0025). The method revealed good inter- and intraobserver agreement with correlation coefficients of about r = 0.90 and r = 0.95, respectively. Inter- and intraobserver coefficients of variation were 6.6% and 4.6%, respectively. CONCLUSION: Determination of the bone marrow uptake ratio is simple and reproducible. The normal values established in this study were age dependent, which has to be considered when interpreting bone marrow uptake ratios. The presence of infection/PUO, solid malignant tumors, lymphomas and plasmacytomas does not seem to alter the AGAb uptake ratio significantly. The most important application of the quantitative analysis of bone marrow scintigraphy could be the diagnosis and follow-up of diseases with depression of the central hemopoietic activity. PMID- 9374348 TI - Utility of indium-111-antimyosin scintigraphy for diagnosis of myocardial damage in systemic sclerosis. AB - The diagnosis of myocardial disease related to systemic sclerosis is often difficult, but it is clinically relevant since the occurrence of a specific ventricular dysfunction is of poor prognosis. This article reports a case of systemic sclerosis with a subacute episode of myocardial disease assessed by 111In-antimyosin antibody, a specific marker of the necrotic myocardial fiber. PMID- 9374349 TI - Evaluation of fluorine-18-BPA-fructose for boron neutron capture treatment planning. AB - Boron neutron capture therapy (BNCT) using 4-[10B]boronophenylalanine-fructose (BPA-Fr) is in Phase II clinical trials to validate BNCT as a treatment for glioblastoma multiforme and melanoma. Successful BNCT depends on knowledge of the distribution of boron-containing agents in both tumor and normal tissue as currently determined by chemical confirmation of boron deposition in surgically removed malignant tissue before BNCT. METHODS: We used PET to noninvasively obtain in vivo information on the pharmacokinetics of the 18F-labeled analog of BPA-Fr in two patients with glioblastoma multiforme. Time-activity curves generated from the bolus injection of 18F-BPA-Fr were coinvolved to simulate a continuous infusion used for BNCT therapy. RESULTS: Distribution of 18F-BPA-Fr by PET was found to be consistent with tumor as identified by MR imaging. The 18F BPA-Fr tumor-to-normal brain uptake ratio was 1.9 in Patient 1 and 3.1 in Patient 2 at 52 min after injection. The 18F-BPA-Fr uptake ratio in glioblastoma paralleled that of nonlabeled BPA-Fr seen in patients as previously determined by boron analysis of human glioblastoma tissue obtained from pre-BNCT surgical biopsy. CONCLUSION: Knowledge of the biodistribution of BPA-Fr enables pre-BNCT calculation of expected tissue dosimetry for a selected dose of BPA-Fr at a specific neutron exposure. Fluorine-18-BPA-Fr PET is capable of providing in vivo BPA-Fr biodistribution data that may prove valuable for patient selection and pre BNCT treatment planning. PMID- 9374350 TI - Parathyroid hyperplasia, thymic carcinoid and pituitary adenoma detected with technetium-99m-MIBI in MEN type I. AB - We report a case of a 57-yr-old woman with history of multiple endocrine neoplasia type I (MEN I). A 99mTc-sestamibi scan demonstrated a hyperplastic parathyroid gland, a large anterior mediastinal mass and a pituitary adenoma during a study done to evaluate recurrent hyperparathyroidism. The importance of this case is that much of the nonparathyroid pathology in patients with MEN I syndrome may be detected with this one study. PMID- 9374351 TI - Primary adrenal lymphoma: gallium scintigraphy and correlative imaging. AB - Primary adrenal lymphoma is a rare entity, with only 16 cases reported in the last 40 yr. Although 67Ga scintigraphy has been extensively used to evaluate patients with other types of lymphomas, there are no reports of its use in patients with this disease entity. A man with primary adrenal lymphoma and no evidence of extraadrenal spread who was evaluated from presentation to remission with gallium scintigraphy and CT is presented. Gallium scintigraphy was valuable in assessing response to therapy. PMID- 9374352 TI - Decision analysis: MIBI imaging of nonpalpable breast abnormalities. AB - Scintimammography using sestamibi has provided exciting preliminary results in evaluating suspicious breast lesions. A computer simulation was performed using projected test characteristics to guide future studies and to evaluate the clinical and financial consequences of the anticipated use of noninvasive breast evaluation strategies. METHODS: A decision analysis model compared sestamibi breast imaging, stereotaxic core biopsy and surgical biopsy as breast evaluation strategies for hypothetical cohorts of 1000 women with nonpalpable breast lesions. All women with a negative original procedure would have a 6-mo follow up. Sensitivity and specificity were estimated from the literature and from a recent multicenter assessment for sestamibi. Probabilities of 10% for both invasive cancer and in situ cancer were based on mammographic features. Costs were based on the costs incurred by patients who were evaluated at our institution and the costs of sestamibi projections. RESULTS: Per 1000 women, core biopsy was projected to miss about seven invasive and 10 in situ cancers more than would surgery. Sestamibi imaging was projected to miss an additional 16 invasive cancers and 12 in situ cancers, compared to core biopsy. Most misses would be detected at 6-mo follow-up. Compared to immediate surgery, the cost would be reduced by 20% with the core biopsy and 39% with the sestamibi strategy. Sixty-five percent of women having sestamibi imaging would avoid any invasive biopsy. The projected cost savings of core biopsy or sestamibi imaging, compared to surgery, ranged fom $17,700 to $77,500 per delayed cancer diagnosis. CONCLUSION: If sestamibi imaging has similar test characteristics outside the research setting, then sestamibi imaging or sterotaxic core biopsy will lead to substantial cost savings compared to surgery with a slight compromise in the rate of early cancer detection. A decision analysis simulation can aid in designing clinical trials and exploring new strategies. The adopting of nonsurgical biopsy techniques will likely depend on confirming or establishing their test characteristics in lower-risk lesions, the natural history of cancers whose diagnosis is delayed and patient preferences of the value on avoiding any form of breast biopsy. PMID- 9374353 TI - A perspective on decision analysis modeling as it relates to sestamibi imaging of nonpalpable breast abnormalities. PMID- 9374354 TI - DTPA aerosol in ventilation/perfusion scintigraphy for diagnosing pulmonary embolism. AB - The use of lung scintigraphy in evaluating suspected pulmonary embolism (PE) is controversial. Several diagnostic methods have been described for lung scans, of which the most widely applied uses 99mTc-MAA for perfusion, 133Xe for ventilation and PIOPED diagnostic criteria. This study evaluates the accuracy of lung scintigraphy using an alternative ventilation agent, 99mTc-diethylenetriamine pentacetic acid (DTPA) aerosol, and specific criteria. METHODS: Diagnostic criteria for DTPA aerosol ventilation were prospectively applied to 5017 patients over a 9-yr period. Lung scan interpretations were analyzed for frequency of occurrence, and results were compared to those of angiography in 455 patients. RESULTS: Scans were interpreted as normal, low or high probability in 79% of patients and as either indeterminate or medium probability in 21% of patients. Three patients had normal scans and negative angiography. In patients with low probability scans, 111 angiograms were performed: 103 (93%) were negative, and 8 (7%) were positive. In patients with indeterminate scans, 114 angiograms were performed: 85 (75%) were negative, and 29 (25%) were positive. In patients with medium-probability scans, 149 angiograms were performed: 86 (58%) were negative, and 63 (42%) were positive. In patients with high-probability scans, 78 angiograms were performed: 6 (8%) were negative, and 72 (92%) were positive. CONCLUSION: These results indicate that lung scintigraphy using DTPA aerosol and our criteria is accurate in diagnosing and stratifying risk of pulmonary embolic disease. Compared with 133Xe and PIOPED criteria, DTPA ventilation and our criteria reduced the false-negative rate in low-probability scans (7% versus 16%, p < 0.005) and decreased the fraction of intermediate-probability scans (21 % versus 39%, p < 0.01). PMID- 9374355 TI - Simplified technetium-99m-EC clearance in adults from a single plasma sample. AB - Technetium-99m-EC has recently been introduced as an alternative renal tubular agent to 131I-ortho iodohippurate (OIH). It has been shown that 99mTc-EC clearance shows strong correlation with OIH clearance and it is possible to estimate effective renal plasma flow. In routine clinical studies, it is practical to use one or two plasma sample methods instead of multiple plasma samples for clearance determination. An attempt was made to determine 99mTc-EC clearance with one sample method. METHODS: Data from 72 subjects were collected. To increase the range of renal function, two anuric hemodialysis patients were also included. Clearances were determined by the open two-compartment model. RESULTS: The clearance range was 12 ml/min to 660 ml/min with a mean of 275 +/- 117 ml/min. Analysis of correlation was made by Tauxe's method. The least standard error of estimation (s.e.e. = 32.71 ml/min) and the best correlation (r = 0.97) between the theoretical volume distribution and the clearance estimations were obtained from the 54-min plasma sample. CONCLUSION: This study suggests that EC clearance could be determined by a simplified single-sample method with an acceptable s.e.e. PMID- 9374356 TI - Technetium-99m-tetrofosmin uptake in sarcoidosis stage I. AB - The uptake of 99mTc-tetrofosmin in enlarged lymph nodes, of the lung hilus, in the case of sarcoidosis Stage I (histopathologically confirmed by mediastinoscopic biopsy) is demonstrated. On a routine chest radiograph of a 78 yr-old woman, hilar lymphadenopathy was first detected. In the following mammography, disseminated micro calcifications were found in the left breast and a 99mTc-tetrofosmin study was performed for detection of breast cancer. Scintigraphy using 99mTc-tetrofosmin showed clear uptake in the hilar lymph nodes, but not in the left breast. The 99mTc-tetrofosmin uptake in the hilar lymph nodes was due to sarcoidosis confirmed by histology. Therefore, 99mTc tetrofosmin scintigraphy may be useful in patients with suspected sarcoidosis, especially in Stage I. PMID- 9374358 TI - Camera-based PET: the best is yet to come. PMID- 9374357 TI - Atherosclerosis: imaging techniques and the evolving role of nuclear medicine. AB - Quantitative assessment of atherosclerotic or atherothrombotic disease during its natural history and following therapeutic interventions is important for understanding the progression and stabilization of the disease and for selecting appropriate medical or surgical interventions. A number of invasive and noninvasive imaging techniques are available to detect and display different characteristics of vascular lesions of clinical and/or research interest. METHODS: Angiography, the traditional "gold standard," detects advanced lesions and measures the degree of stenosis. Angioscopy clearly identifies thrombus. In carotid arteries and arteries in lower extremities, duplex ultrasonography is useful for providing the degree of stenosis, as well as plaque morphology, and assessing changes in wall thickness. RESULTS: Magnetic resonance angiography, being noninvasive, may replace conventional angiography for anatomical imaging of the vasculature. Ultrafast electron beam CT measures the calcium content in the atherosclerotic lesions. Intravascular ultrasound is the only technique that appears to be clinically useful in imaging the unstable, vulnerable plaques in coronary arteries. Magnetic resonance imaging techniques may be able to image vulnerable plaques and characterize plaques in terms of lipid and fibrous content and identify the presence of thrombus associated with the plaques. In regard to the nuclear scientigraphic imaging techniques, radiolabeled lipoproteins, platelets and immunoglobulins have shown some clinical potential as imaging agents, but due to poor target-to-background and target-to-blood ratios these agents are not ideal for imaging coronary or even carotid lesions. Technetium-99m labeled peptides and monoclonal antibody fragments that clear from circulation rapidly and bind specifically to different components of the atherosclerotic lesion showed significant potential in animal models and in limited clinical studies. FRE Peptides capable of binding to GPIIb/IIIA receptors on activated platelets appear to offer significant diagnostic potential for imaging intra arterial thrombus. Positron emission tomography with metabolic tracers like [18F] fluorodeoxyglucose (FDG) also appears to offer new opportunities for noninvasive imaging of atherosclerosis and atherothrombosis. PMID- 9374360 TI - Colonic transit scintigraphy labeled activated charcoal compared with ion exchange pellets. AB - Scintigraphic measurement of colonic transit is currently performed by delivering 111In ion exchange resin pellets to the colon in a methacrylate-coated capsule. However, use of this method is constrained by the need for an investigational drug permit. We have demonstrated previously optimal adsorption in vitro of commonly used radioisotopes (e.g., 99mTc or 111In) to activated charcoal in milieus that mimicked gastric and small intestinal content. The aim of this study was to compare the transit profiles of radioactive activated charcoal and resin pellets delivered to the colon in the same methacrylate-coated capsule. METHODS: In 10 healthy volunteers, we compared the colonic transit profiles over 32 hr of simultaneously administered resin pellets labeled with 111In and activated charcoal mixed with 99mTc-diethylenetriaminepentaacetic acid. Transit was summarized as the geometric center (weighted average of counts) in the colon at each scanning period. RESULTS: Colonic transit profiles were virtually identical with the two markers, with less than 0.1 geometric center unit differences in the transit profiles over the 32-hr periods. CONCLUSION: Activated charcoal is a suitable alternative to resin pellets when delivered in a methacrylate-coated, delayed-release capsule to the colon for measurement of transit by scintigraphy. PMID- 9374359 TI - Asialoglycoprotein receptor and hepatic blood flow using technetium-99m-DTPA galactosyl human serum albumin. AB - Asialoglycoprotein receptor (ASGP-R) amount and hepatic blood flow were quantitatively measured by using a newly developed kinetic model of 99mTc-labeled diethylenetriaminepentaacetic acid-galactosyl human serum albumin (99mTc-GSA) in which receptor-mediated endocytosis and receptor recycling were considered. METHODS: Five healthy volunteers were intravenously injected 3-mg and 9-mg 99mTc GSA doses. The absolute amounts of 99mTc-GSA in the liver and extrahepatic blood were estimated from the time-activity curves for the liver, heart and lung. The metabolic process was represented by five differential equations with 10 parameters as variables. To estimate total receptor amount (Rtotal), hepatic plasma flow (Q) and hepatic plasma volume (Vh), other parameters were fixed and estimated by analyzing their data with the least-squares method. Nineteen patients with liver diseases were given a 3-mg dose, and the data were analyzed to estimate Rtotal, Q and Vh. RESULTS: The values of the fixed parameters were estimated as follows: dissociation constant, 0.032 microM; rate constant for internalization, 0.604 min(-1); and ratio of surface receptors to total receptors, 6.1%. The fitted liver uptake curve corresponded well to the measured data. The simulated liver uptake curve was significantly influenced by Rtotal and Q in cases with normal receptor amounts. Analysis in patients with normal livers, chronic hepatitis and liver cirrhosis showed statistically significant differences in their Rtotal values, but not in their Q or Vh values. The s.e. values of Rtotal, Q and Vh for normal livers were small, and the s.e. values of Q and Vh were high for cirrhotic livers. CONCLUSION: This method is useful for measuring ASGP-R amount and hepatic blood flow simultaneously based on dynamic images, without the need for blood sampling, and reflects the cellular transport of asialoglycoproteins and the ASGP-R recycling mechanism. PMID- 9374361 TI - Ifosfamide-induced alteration of technetium-99m-DMSA renal parenchymal imaging. AB - Renal cortical imaging with 99mTc-dimercaptosuccinic acid (DMSA) has become the imaging test of choice for the diagnosis of acute pyelonephritis. An unusual uptake pattern was observed in a child receiving chemotherapy for a bladder rhabdomyosarcoma. Chemotherapy from ifosfamide produces a specific pattern of injury to the renal tubule that alters uptake of DMSA. PMID- 9374362 TI - Lung scintigraphy in postpneumonectomy dyspnea due to a right-to-left shunt. AB - We report the case of a 50-yr-old man who experienced exertional dyspnea 5 mo after a left pneumonectomy for carcinoma. As the clinical features pointed toward a pulmonary embolism, we performed a ventilation plus perfusion radionuclide lung scan. It showed no evidence of pulmonary embolism, but it did show a systemic uptake of the isotope, suggesting a right-to-left shunt that was confirmed by contrast echocardiography, which revealed an atrial septal defect. Right-to-left shunts after pneumonectomy have already been reported and can be diagnosed by lung scintigraphy. Usually, a patent foramen ovale is encountered, but the underlying physiopathology remains under discussion. Clinically, right-to-left shunts are often related to platypnea-orthodeoxia. PMID- 9374364 TI - Requirements and implementation of a flexible kinetic modeling tool. AB - Kinetic (or compartment) modeling is a highly versatile tool for the analysis of experiments within living systems. In PET, it is essential for developing tracers, for assessing tracer behavior and for extracting quantitative information about the target process. However, tools to support the modeling tasks involved are not easily available. METHODS: This article presents a requirements analysis for kinetic modeling in PET. The interactive kinetic modeling tool KMZ implements many of these features. It facilitates model development by a set of predefined models and by the ease of introducing new models. Monte Carlo studies allow assessing parameter identifiability. The responses in the different compartments as well as the expected time-activity curve can be simulated for specific model configurations. For measured time activity curves, model optimization can be performed by the Powell or the Marquardt algorithm. Both support weighted nonlinear least-squares fitting and allow optional constraints of parameter ranges. To further improve parameter estimation, the fitting of several regional time-activity curves can be coupled, resulting in lower standard errors for parameters common among regions. It is possible to highly automate the evaluation of study series and to forward the results into statistical analysis tools. RESULTS: The KMZ tool has proven highly suitable in evaluating data from different types of studies, and the intuitive user interface enables medical doctors to successfully perform routine evaluations after a short training period. CONCLUSION: A portable kinetic modeling tool with the described features would provide easy access to model development and may help consolidate kinetic modeling in clinical settings for well-defined applications. PMID- 9374365 TI - Biliary dyskinesia: role of the sphincter of Oddi, gallbladder and cholecystokinin. AB - The availability of objective and quantitative diagnostic tests in recent years has allowed more precise documentation of biliary dyskinesia. Biliary dyskinesia consists of two disease entities situated at two different anatomical locations: sphincter of Oddi spasm, at the distal end of the common duct, and cystic duct syndrome, in the gallbladder. Both conditions are characterized by a paradoxical response in which the sphincter of Oddi and the cystic duct contract (and impede bile flow) instead of undergoing the normal dilatation, when the physiological dose of cholecystokinin is infused. Quantitative cholescintigraphy can clearly differentiate one disease entity from the other. The therapies of choice are sphincterotomy, sphincteroplasty or antispasmodics for sphincter of Oddi spasm and cholecystectomy for cystic duct syndrome. After quantitative cholescintigraphy, the final impression should identify the disease entity by name to assist the referring physician in making an appropriate therapeutic decision; a mere statement that a test is consistent with biliary dyskinesia is no longer sufficient. PMID- 9374363 TI - Jod-Basedow syndrome following oral iodine and radioiodinated-antibody administration. AB - This is a case of thyrotoxicosis, presumably due to Jod-Basedow syndrome, after stable iodine ingestion for thyroid blockade in a patient with ovarian carcinoma having 131I-labeled monoclonal antibody imaging. With the increased use of radioiodinated antibodies, for therapy and imaging, this possible side effect of excess stable iodine administration should be noted, especially in patients with pre-existing goiter. PMID- 9374366 TI - Mallory-Weiss syndrome caused by iodine-131 therapy for metastatic thyroid carcinoma. PMID- 9374367 TI - Written instructions for the release of patients administered radiopharmaceuticals. PMID- 9374368 TI - Tumour-derived interleukin 1alpha (IL-1alpha) up-regulates the release of soluble intercellular adhesion molecule-1 (sICAM-1) by endothelial cells. AB - Levels of circulating soluble intercellular adhesion molecule-1 (sICAM-1) are elevated in patients affected by solid malignancies; however, the cellular sources generating high levels of sICAM-1 remain to be characterized. Using conditioned media (CM) from seven ICAM-1-positive or -negative neoplastic cells, we demonstrate that tumour-derived interleukin 1alpha (IL-1alpha) significantly (P < 0.05) up-regulates the release of sICAM-1 by human umbilical vein endothelial cells. The intensity of the effect correlated with the amounts of IL 1alpha detectable in CM. Levels of ICAM-1 mRNA were also up-regulated by tumour secreted IL-1alpha. The up-regulation of the shedding of sICAM-1 and of its expression at protein and mRNA level were completely reversed by the addition of anti-IL-1alpha neutralizing antibodies. Consistent with the in vitro data, tumour endothelia were strongly stained for ICAM-1 compared with autologous normal tissue endothelia. Taken altogether, our observations reveal an IL-1alpha mediated tumour-endothelium relationship sustaining the shedding of sICAM-1 by endothelial cells. This is a general phenomenon in solid malignancies that correlates with the ability of neoplastic cells to secrete IL-1alpha rather than with their expression of ICAM-1 and/or histological origin. sICAM-1 has been previously shown to inhibit LFA-1/ICAM-1-mediated cell-cell interactions; therefore, the ability of neoplastic cells to secrete IL-1alpha is likely to represent a mechanism for their escape from immune interaction. PMID- 9374369 TI - Autocrine growth induced by transferrin-like substance in bladder carcinoma cells. AB - Ample evidence confirms that certain cancer cells have the capacity to produce multiple peptides as growth factors and that expression of their receptor may act in tumour cell paracrine and/or autocrine loop mechanisms, either by extracellular release of the growth factor or by the tumour itself. To study the possibility of an autocrine growth mechanism in bladder carcinoma, we investigated the ability of various bladder carcinoma cell lines to proliferate in serum-free medium. A rat bladder carcinoma cell line, BC47, demonstrated exponential and density-dependent growth in serum-free medium. Furthermore, conditioned medium from BC47 cells induced growth-stimulating activity for BC47 cells themselves. Purification and further characterization of this activity was performed by chromatographic methods, SDS-PAGE and N-terminal amino acid analysis. Finally, we have identified that a transferrin-like 70-kDa protein is found to be the main growth-promoting factor in this conditioned medium. In addition, specific antibodies against transferrin and the transferrin-receptor inhibit the in vitro growth of this cell line. Our data suggest that this transferrin-like factor possibly acts as an autocrine growth factor for cancer cells. PMID- 9374370 TI - A recurrent pattern of chromosomal aberrations and immunophenotypic appearance defines anal squamous cell carcinomas. AB - Squamous cell carcinomas of the anus are rare neoplasias that account for about 3% of large bowel tumours. Infections with human papillomaviruses are frequently detected in these cancers, suggesting that pathogenic pathways in anal carcinomas and in carcinomas of the uterine cervix are similar. Little is known regarding recurrent chromosomal aberrations in this subgroup of squamous cell carcinomas. We have applied comparative genomic hybridization to identify chromosomal gains and losses in 23 cases of anal carcinomas. A non-random copy number increase of chromosomes 17 and 19, and chromosome arm 3q was observed. Consistent losses were mapped to chromosome arms 4p, 11q, 13q and 18q. A majority of the tumours were aneuploid, and most of them showed increased proliferative activity as determined by staining for Ki-67 antigen. p53 expression was low or undetectable, and expression of p21/WAF-1 was increased in most tumours. Sixteen cancers were satisfactorily tested for the presence of HPV by consensus L1-primer polymerase chain reaction; nine were HPV positive, of which eight were positive for HPV 16. PMID- 9374371 TI - Dietary chemoprevention of clastogenic effects of 3,4-benzo(a)pyrene by Emblica officinalis Gaertn. fruit extract. AB - Dietary supplementation with extract of fruit of Emblica officinalis Gaertn. (a rich source of vitamin C) to mice in vivo significantly reduced the cytotoxic effects of a known carcinogen, 3,4-benzo(a)pyrene. Age-matched Swiss albino mice were fed by gavaging the fruit extract daily for 28 days. From day 9, one dose of the carcinogen was given on alternate days up to a total of eight doses. On day 29, all mice were transferred to normal diet. Control sets received the extract alone, the carcinogen alone and olive oil alone. All mice were sacrificed at 12 weeks and 14 weeks after the end of the experiment. Chromosome preparations were made from bone marrow after the usual colchicine-hypotonic-fixative-air drying Giemsa staining schedule. Cytogenetic end points screened were the frequencies of chromosomal aberrations and of damaged cells induced. The cytotoxic effects were significantly lower in the mice given the fruit extract with the carcinogen than in those given the carcinogen alone. PMID- 9374372 TI - Deletion mapping on chromosome 17p in medulloblastoma. AB - Medulloblastoma is the most frequent paediatric brain tumour. Because of the uniform histology, a common genetic mechanism has been postulated. Loss of heterozygosity (LOH) studies support evidence that a candidate gene, which functions as a tumour-suppressor gene, is located in 17p13. Eighteen tumours were examined for loss of heterozygosity at 15 different loci at chromosome 17p. Nine of 18 (50%) tumours had allelic loss in 17p 13.3-13.2. The smallest region of overlap, which harbours the disease gene, includes markers from UT222 (D17S675) to UT49 (D17S731) and spans a region of less than 6 cM. Candidate genes within this region are HIC-1, a potential tumour-suppressor gene, and DPH2L, a gene that has been cloned from the ovarian critical region. The putative region excludes the p53 gene and the ABR gene, which have been favoured by others. LOH of chromosome 17p may be used as a new prognostic biological marker. Children with an allelic loss had a poorer prognosis than those patients without loss of heterozygosity (P<0.05). PMID- 9374373 TI - Lack of cyclin E immunoreactivity in non-malignant breast and association with proliferation in breast cancer. AB - Cyclin E is a G1 cyclin that is essential for the transition from G1 to S phase in the cell cycle. Alterations to cyclin E expression or regulation could be important in tumorigenesis. Previous immunohistochemical and immunoblotting studies have investigated the expression of cyclin E in breast carcinomas. In this study, cyclin E has been investigated in a range of non-malignant and malignant breast using immunohistochemistry. Normal and benign tissue from pre- and post-menopausal women (39 cases), non-involved tissue from cancer-containing breasts (47 cases), ductal carcinoma in situ (22 cases) and invasive breast carcinomas (109 cases) have been examined. There was no reactivity in any of the non-malignant breast. Only one ductal carcinoma in situ contained more than 5% reactive cells. A total of 28% of invasive carcinomas had > 5% of reactive cells (range 0-88% positive cells, mean 12.59%, median 1.0%). A significant association was found with poorer differentiation (P < 0.001), high MIB1 index (P < 0.001), lack of oestrogen receptor (0.05 > P > 0.025) and the presence of p53 protein (0.05 > P > 0.025). Virtually all cases with cyclin E and p53 were poorly differentiated. The presence of cyclin E is therefore only found in breast malignancies and is associated with more aggressive features, including high proliferation. PMID- 9374374 TI - Detection of mutant K-ras DNA in plasma or serum of patients with colorectal cancer. AB - Increased understanding of the molecular basis of colorectal cancer and recognition that extracellular DNA circulates in the plasma and serum of cancer patients enables new approaches to detection and monitoring. We used a polymerase chain reaction (PCR) assay to demonstrate mutant K-ras DNA in the plasma or serum of patients with colorectal cancer. Plasma or serum was fractionated from the blood of 31 patients with metastatic or unresected colorectal cancer and from 28 normal volunteers. DNA was extracted using either a sodium chloride or a gelatin precipitation method and then amplified in a two-stage PCR assay using selective restriction enzyme digestion to enrich for mutant K-ras DNA. Mutant K-ras DNA was detected in the plasma or serum of 12 (39%) patients, all confirmed by sequencing, but was not detected in any of the normal volunteers. K-ras mutations were detected in plasma or serum regardless of sex, primary tumour location, principal site of metastasis or proximity of chemotherapy and surgery to blood sampling. Tumour specimens available for 19 of the patients were additionally assayed for ras mutations and compared with blood specimens. Our results indicate mutant K-ras DNA is readily detectable by PCR in the plasma or serum of patients with advanced colorectal cancer. Thus, plasma- or serum-based nucleic acid amplification assays may provide a valuable method of monitoring and potentially detecting colorectal cancer. PMID- 9374375 TI - Selective potentiation of lometrexol growth inhibition by dipyridamole through cell-specific inhibition of hypoxanthine salvage. AB - The novel antifolate lometrexol (5,10-dideazatetrahydrofolate) inhibits de novo purine biosynthesis, and co-incubation with hypoxanthine abolishes its cytotoxicity. The prevention of hypoxanthine rescue from an antipurine antifolate by the nucleoside transport inhibitor dipyridamole was investigated for the first time in nine human and rodent cell lines from seven different tissues of origin. In A549, HeLa and CHO cells, dipyridamole prevented hypoxanthine rescue and so growth was inhibited by the combination of lometrexol, dipyridamole and hypoxanthine, but in HT29, HCT116, KK47, MDA231, CCRF CEM and L1210 cells dipyridamole had no effect and the combination did not inhibit growth. Dipyridamole inhibited hypoxanthine uptake in A549 but not in CCRF CEM cells. Dipyridamole prevented the hypoxanthine-induced repletion of dGTP pools, depleted by lometrexol, in A549 but not in CCRF CEM cells. Thus, the selective growth inhibitory effect of the combination of lometrexol, dipyridamole and hypoxanthine is apparently due to the dipyridamole sensitivity (ds) or insensitivity (di) of hypoxanthine transport. Both the human and murine leukaemic cells are of the di phenotype. If this reflects the transport phenotype of normal bone marrow it would suggest that the combination of lometrexol, dipyridamole and hypoxanthine might be selectively toxic to certain tumour types and have reduced toxicity to the bone marrow. PMID- 9374376 TI - Use of power Doppler ultrasound-guided biopsies to locate regions of tumour hypoxia. AB - The purpose of this study was to determine whether power Doppler ultrasound techniques could be used to direct biopsies into tumour regions with relatively low red blood cell flux, and therefore preferentially sample regions that were relatively hypoxic. Subcutaneous 9L glioma rat tumours were biopsied using power Doppler ultrasound guidance. Immunohistochemical detection of the 2 nitroimidazole EF5 was performed to determine the presence and level of hypoxia in the biopsy samples. Comparisons between the power Doppler-determined red blood cell flux and EF5 binding were made. In seven out of eight tumours studied, power Doppler ultrasound allowed differentiation of a relatively hypoxic region from a relatively oxic region by localizing relatively low vs high red blood cell flux areas respectively. In one of these seven tumours, RBC flux was high in both biopsied sites and hypoxia was not present in either. In two of these seven tumours, hypoxia was present in each biopsy and both of the red blood cell flux measurements were low. In the eighth tumour, both the EF5 binding and the red blood cell flux measurements were low. In this tumour, low EF5 binding was due to the dominance of necrotic cells, which will not reduce or bind EF5 in the biopsy specimen. Using EF5-binding techniques, we have confirmed that regions of relatively low red blood cell flux are more hypoxic than those with relatively high red blood cell flux. Counterstaining specimens with haematoxylin and eosin allows differentiation of low EF5-binding regions due to oxia vs necrosis. These methods have clinical implications for the expanded use of power Doppler ultrasound as a means to direct tissue sampling when it is important to identify the presence of hypoxia. PMID- 9374377 TI - Kinetics of mouse jejunum radiosensitization by 2',2'-difluorodeoxycytidine (gemcitabine) and its relationship with pharmacodynamics of DNA synthesis inhibition and cell cycle redistribution in crypt cells. AB - Gemcitabine (dFdC), a deoxycitidine nucleoside analogue, inhibits DNA synthesis and repair of radiation-induced chromosome breaks in vitro, radiosensitizes various human and mouse cells in vitro and shows clinical activity in several tumours. Limited data are however available on the effect of dFdC on normal tissue radiotolerance and on factors associated with dFdC's radiosensitization in vivo. The purpose of this study was to determine the effect of dFdC on mouse jejunum radiosensitization and to investigate the kinetics of DNA synthesis inhibition and cell cycle redistribution in the jejunal crypts as surrogates of radiosensitization in vivo. For assessment of jejunum tolerance, the mice were irradiated on the whole body with 60Co gamma rays (3.5-18 Gy single dose) with or without prior administration of dFdC (150 mg kg-1). Jejunum tolerance was evaluated by the number of regenerated crypts per circumference at 86 h after irradiation. For pharmacodynamic studies, dFdC (150 or 600 mg kg-1) was given i.p. and jejunum was harvested at various times (0-48 h), preceded by a pulse BrdUrd labelling. Labelled cells were detected by immunohistochemistry on paraffin-embedded sections. DNA synthesis was inhibited within 3 h after dFdC administration. After an early wave of apoptosis (3-6 h), DNA synthesis recovered by 6 h, and crypt cells became synchronized. At 48 h, the labelling index returned almost to background level. At a level of 40 regenerated crypts, radiosensitization was observed for a 3 h time interval (dose modification factor of 1.3) and was associated with DNA synthesis inhibition, whereas a slight radioprotection was observed for a 48-h time interval (dose modification factor of 0.9) when DNA synthesis has reinitiated. In conclusion, dFdC altered the radioresponse of the mouse jejunum in a schedule-dependent fashion. Our data tend to support the hypothesis that DNA synthesis inhibition and cell cycle redistribution are surrogates for radiosensitization. More data points are however required before a definite conclusion can be drawn. PMID- 9374378 TI - Reduced expression of the ICE-related protease CPP32 is associated with radiation induced cisplatin resistance in HeLa cells. AB - Low-dose fractionated gamma-irradiation (three cycles of 5 x 2 Gy) induced cisplatin resistance in HeLa cells. The drug resistance was modest (Rf of about 2) and stable, similar to that found previously in murine cells after irradiation. In the drug-resistant HeLa-C3 cells, flow cytometric analysis revealed a decreased number of apoptotic cells compared with the parental cells. Drug resistance was associated with considerably enhanced expression of the p53 suppressor protein in HeLa-C3 cells after cisplatin exposure but seemed not to be regulated by the bcl-2-dependent pathway. Cisplatin resistance correlated with reduced expression of ICE-related proteases (interleukin-1beta-converting enzyme). Basal levels of the 45-kDa precursor ICE protein were reduced in HeLa-C3 cells, while those of the mature 60-kDa heterotetramer were similar. The CPP32 protease, a member of the ICE family with structural homology but different substrate specificity, was expressed at a lowered level. After drug exposure, there was a slight increase of CPP32 in HeLa-C3 cells, equivalent to about 45% of the level attained in the parental cells. This is in contrast to the CPP32 levels measured after irradiation, which were similar in sensitive and in resistant cells. As the radiosensitivity is unchanged in both cell lines, these results suggest that cisplatin resistance in HeLa-C3 cells is associated with alterations of a CPP32-linked apoptotic pathway, which is affected by the damage caused by cisplatin but not by irradiation. Whether these changes are dependent on the observed p53 modifications is now being studied in resistant clones. PMID- 9374379 TI - Cisplatin resistance is associated with reduced interferon-gamma-sensitivity and increased HER-2 expression in cultured ovarian carcinoma cells. AB - In ovarian carcinoma cells, the combination of interferon-gamma (IFN-gamma) and cisplatin (cDDP) has been reported to result in a synergistic amplification of antiproliferative activity. To assess whether IFN-gamma may also prevent the occurrence of cisplatin resistance, the human ovarian carcinoma cell line HTB-77 was treated repeatedly in an intermittent fashion with either cisplatin alone (HTB-77cDDP) or cisplatin plus IFN-gamma (HTB-77cDDP + IFN). After 8 months of treatment, both new lines (HTB-77cDDP or HTB-77cDDP + IFN) were found to be three times more resistant to cisplatin than the wild-type cells (HTB-77wt). IFN-gamma could not prevent the development of cisplatin resistance. Interestingly, both HTB-77cDDP and HTB-77cDDP + IFN cells were also less IFN-gamma sensitive than the parental line. Both cisplatin-resistant lines expressed p185HER-2 and HER-2 mRNA at a higher concentration than the HTB-77wt cells. IFN-gamma was in all three HTB 77 cell lines able to suppress the HER-2 message and its encoded protein. The expression of IFN-gamma-induced antigens, namely CA-125 and class II antigens of the major histocompatibility complex (HLA-DR), was markedly augmented by IFN gamma in all three lines, whereby the most prominent effect was seen in HTB 77cDDP and HTB-77cDDP + IFN. PMID- 9374380 TI - Glutathione-doxorubicin conjugate expresses potent cytotoxicity by suppression of glutathione S-transferase activity: comparison between doxorubicin-sensitive and resistant rat hepatoma cells. AB - The cytotoxic mechanism of a conjugate of doxorubicin (DXR) and glutathione (GSH) via glutaraldehyde (GSH-DXR) was investigated using DXR-sensitive (AH66P) and resistant (AH66DR) rat hepatoma cells. GSH-DXR accumulated in AH66DR cells as well as in AH66P cells without efflux by P-gp and exhibited the potent cytocidal activity against both cells compared with DXR. To examine whether thiol from GSH DXR affected the expression of cytotoxicity, two conjugates of DXR, with modified peptides containing alanine or serine substituted for cysteine in GSH were prepared and their cytotoxicities determined. Substitution of these amino acids for cysteine resulted in an approximately two- to fourfold reduction in cytotoxic activity against both cell lines compared with the effect of GSH-DXR. Depletion of intracellular GSH by treatment of both cells with buthionine sulphoximine did not change the cytotoxic activity of DXR, BSA-DXR or GSH-DXR. By co-treating the cells with tributyltin acetate, an inhibitor of glutathione S-transferase (GST), and either DXR, BSA-DXR or GSH-DXR, the cytotoxicity was markedly increased. Interestingly, GSH-DXR showed non-competitive inhibition of GST activity and its IC50 value was 1.3 microM. These results suggested that the inhibition of GST activity by GSH-DXR must be an important contribution to the expression of potent cytotoxicity of the drug. PMID- 9374381 TI - Overexpression of human NADPH:cytochrome c (P450) reductase confers enhanced sensitivity to both tirapazamine (SR 4233) and RSU 1069. AB - P450 reductase (NADPH: cytochrome c (P450) reductase, EC 1.6.2.4) plays an important role in the reductive activation of the bioreductive drug tirapazamine (SR4233). Thus, in a panel of human breast cancer cell lines, expression of P450 reductase correlated with both the hypoxic toxicity and the metabolism of tirapazamine [Patterson et al (1995) Br J Cancer 72: 1144-1150]. To examine this dependence in more detail, the MDA231 cell line, which has the lowest activity of P450 reductase in our breast cell line panel, was transfected with the human P450 reductase cDNA. Isolated clones expressed a 78-kDa protein, which was detected with anti-P450 reductase antibody, and were shown to have up to a 53-fold increase in activity of the enzyme. Using six stable transfected clones covering the 53-fold range of activity of P450 reductase, it was shown that the enzyme activity correlated directly with both hypoxic and aerobic toxicity of tirapazamine, and metabolism of the drug under hypoxic conditions. No metabolism was detected under aerobic conditions. For RSU1069, toxicity was also correlated with P450 reductase activity, but only under hypoxic conditions. Measurable activity of P450 reductase was found in a selection of 14 primary human breast tumours. Activity covered an 18-fold range, which was generally higher than that seen in cell lines but within the range of activity measured in the transfected clones. These results suggest that if breast tumours have significant areas of low oxygen tension, then they are likely to be highly sensitive to the cytotoxic action of tirapazamine and RSU 1069. PMID- 9374382 TI - High-resolution HLA-DRB1 and DQB1 genotyping in Japanese patients with testicular germ cell carcinoma. AB - We report for the first time the frequency distributions of HLA-DRB1 and -DQB1 genes in 55 patients with testicular germ cell carcinoma (TGC) using the modified PCR-RFLP method and compare the results with those for 1216 healthy Japanese control subjects. The modified PCR-RFLP method produced accurate, reproducible cleavage patterns that are easily discriminated. HLA-DRB1*0410 was the susceptibility allele (RR = 3.26, P = 0.006) and DQB1*0602 appears to be a candidate protective allele (RR = 0.26, P = 0.02) for TGC in the Japanese. None of the HLA-DRB1 and -DQB1 alleles showed a specific tendency for histological type or clinical stage of the tumours. Previous studies based on serotyping methods failed to show these allelic associations. High-resolution genotyping is essential because the peptide-binding domain of MHC class II molecules is determined more precisely by their genotypes than by their serotypes. In addition, inherent technical difficulties and typing errors of up to 25% make serotyping inefficient. Our results suggest that high-resolution genotyping is a useful genetic marker to determine risk for TGC. PMID- 9374383 TI - Assessment of cytotoxic T-lymphocyte phenotype using the specific markers granzyme B and TIA-1 in cervical neoplastic lesions. AB - Cervical carcinomas are closely associated with high-risk human papillomavirus (HPV) types and are preceded by cervical intraepithelial neoplasia (CIN). Most CIN lesions regress spontaneously and will not evolve to invasive carcinoma. The cellular immune system mediated by cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells are thought to play an important role in the ultimate decline of CIN lesions. Although TIA-1 is constitutively expressed in the majority of circulating T cells and defines a subpopulation of CD8+ T cells with cytotoxic potential, granzyme B is only expressed in CTLs upon activation. In the present study we have evaluated the expression of these proteins by lymphocytes present in 24 randomly chosen CIN lesions with increasing degree of atypia and in 14 cervical squamous cell carcinomas. As major histocompatibility complex (MHC) class I expression is frequently down-regulated in HPV-induced lesions, thus possibly frustrating tumour cell recognition by infiltrating CTLs, these lesions were also analysed for MHC class I expression. The results indicated that in most CIN lesions only a minority of CTLs are activated, whereas in some carcinomas a massive infiltration of activated, i.e. granzyme B-positive, CTLs were observed. The percentage of activated CTLs was not related to expression of MHC class I on neoplastic cells. These results suggest that in some carcinomas proper activation of CTLs occurs but that most likely local factors or immunoselection of resistant neoplastic cells inhibit a proper response of CTLs to these neoplastic cells. PMID- 9374384 TI - High frequency of p53 protein expression in thymic carcinoma but not in thymoma. AB - Thymic epithelial tumours are broadly classified into thymomas and thymic carcinomas. Although both tumours occasionally show invasive growth, they exhibit different clinical and biological findings. The oncogene and anti-oncogene in thymic epithelial tumours have not been evaluated fully. We investigated the expression of p53 protein by immunohistochemical analysis using the anti-p53 polyclonal antibody (CM-1) in 17 thymomas and 19 thymic carcinomas. We also examined p53 gene (exon 5-8) mutation in 18 thymic carcinomas by using polymerase chain reaction-single-strand conformation polymorphism methods and direct sequencing. Of the thymoma cases, only one invasive thymoma showed focal nuclear staining. Fourteen of the 19 thymic carcinomas (74%) showed nuclear staining. Point mutations of the p53 gene were recognized in only 2 of the 18 thymic carcinomas (11%). One was the mutation C to T transition in the first letter of codon 222 in exon 6, which results in the amino acid substitution from proline to serine. Another was a silent mutation. p53 protein accumulation is highly frequent in thymic carcinomas but not in thymomas, and gene mutation is uncommon in thymic carcinomas. PMID- 9374385 TI - Relationship between vascularity, age and survival in non-small-cell lung cancer. AB - Lung tumours in the elderly show reduced growth potential; impaired angiogenesis may contribute to this phenomenon. Recent studies have suggested that the angiogenic potential of a tumour may be inferred by the vascularity measured in histological sections. The purpose of this study has been to determine whether vascularity is related to age, survival or other clinical parameters in resected non-small-cell lung cancer (NSCLC). A group of 88 consecutive patients with a follow-up period of at least 5 years was selected. The group exhibited a wide age range (37-78 years) and similar survival characteristics to those of the general NSCLC population. Tumour sections were stained with a pan-endothelial antibody (vWF) and vascularity was quantitated, without knowledge of the clinical details, by three methods: highest microvascular density; average microvascular density; and average microvascular volume. The results were analysed by non-parametric statistical tests. A correlation was found between all three methods of quantitation. Vascularity was not associated with age, sex, tumour type, stage, volume, size (TNM-T) nodal status (TNM-N) or survival. However, survival time was generally longer for patients with higher vascularity, reaching borderline significance (P = 0.06) for the average microvascular density values. Higher tumour volume (P = 0.02) and stage (P = 0.05) were associated with lower survival times. Using multivariate survival analysis, tumour volume was the only factor related to survival. We conclude that vascularity is not associated with age and has no significant prognostic value in NSCLC. PMID- 9374386 TI - Phase IB study of doxorubicin in combination with the multidrug resistance reversing agent S9788 in advanced colorectal and renal cell cancer. AB - S9788 is a new triazineaminopiperidine derivate capable of reversing multidrug resistance (MDR) in cells resistant to chemotherapeutic agents such as doxorubicin. It does not belong to a known class of MDR revertants, but its action involves the binding of P-glycoprotein. Thirty-eight evaluable patients with advanced colorectal or renal cell cancer were treated with doxorubicin alone (16 patients) followed after disease progression with combination treatment of doxorubicin plus S9788 (12 patients) or upfront with the combination of doxorubicin plus S9788 (22 patients). S9788 was given i.v. as a loading dose of 56 mg m-2 over 30 min followed by doxorubicin given at 50 mg m-2 as a bolus infusion. Thereafter, a 2-h infusion of S9788 was administered at escalating doses ranging from 24 to 120 mg m-2 in subsequent cohorts of 4-10 patients. Pharmacokinetic analysis demonstrated that concentrations of S9788 that are known to reverse MDR in vitro were achieved in patients at non-toxic doses. Compared with treatment with doxorubicin alone, treatment with the combination of doxorubicin and S9788 produced a significant increase in the occurrence of WHO grade 3-4 granulocytopenia. Treatment with S9788 was cardiotoxic as it caused a dose-dependent and reversible increase in corrected QT intervals as well as clinically non-significant arrhythmias on 24- or 48-h Holter recordings. Although clinically relevant cardiac toxicities did not occur, the study was terminated as higher doses of S9788 may increase the risk of severe cardiac arrhythmias. Twenty nine patients treated with S9788 plus doxorubicin were evaluable for response, and one patient, who progressed after treatment with doxorubicin alone, achieved a partial response. We conclude that S9788 administered at the doses and schedule used in this study results in relevant plasma concentrations in humans and can safely be administered in combination with doxorubicin. PMID- 9374387 TI - Pulmonary function in patients with trophoblastic disease treated with low-dose methotrexate. AB - The Sheffield Trophoblastic Disease Centre treats about 25 patients with persistent trophoblastic disease each year. A total of 75% of patients are classified as low risk according to the Charing Cross Hospital prognostic scoring system and receive methotrexate (MTX) 50 mg, i.m., on days 1, 3, 5, 7 with folinic acid 7.5 mg orally 24 h after each methotrexate injection. There is a 7 day rest between treatment cycles. Remission is achieved in 85% of cases. Approximately 20% of patients experienced pleuritic chest pain and dyspnoea. We have evaluated prospectively lung function in 16 low-risk patients receiving methotrexate. All patients had pulmonary function tests [spirometry-forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow rate (PEFR), and transfer factor - TLCO, kCO] performed before and after completed treatment. A mean of 7.5 cycles of MTX were administered (range 4-11). There was a significant reduction in the mean TLCO (mean pre/post 8.15/7.38 mmol min-1 kPa-1, P = 0.01), but there were no other statistically significant changes. Three patients experienced respiratory symptoms and were found to have a 39%, 28%, and 11% reduction in TLCO from baseline, improving on follow up to pretreatment levels. Low-dose MTX is an effective therapy but may cause troublesome pulmonary toxicity. PMID- 9374388 TI - Serum M3/M21 in ovarian cancer patients. AB - Cytokeratins are polypeptides that constitute a subclass of intermediate filaments in epithelial cells. The aim of the present study was to evaluate the clinical usefulness of the serum evaluation of M3/M21 in patients with ovarian cancer. This retrospective study comprises 75 patients suffering from ovarian cancer FIGO stages Ia-III. M3/M21 reached a sensitivity of 78%, a specificity of 85%, a PPV of 89% and a NPV of 83% using a cut-off level of 45 U 1(-1). Forty four women developed recurrent disease after complete remission during the observation period. M3/M21 showed lead time effects in 19 patients, ranging from 2 to 8 months (median 3.2 months). Elevated M3/M21 serum levels before therapy were associated with a poor overall survival (log-rank test, P = 0.02). Considering these preliminary results, the value of M3/M21 as a serum tumour marker, i.e. to evaluate the tumour burden, seems promising. PMID- 9374389 TI - A phase II study of regional 2-weekly 5-fluorouracil infusion with intravenous folinic acid in the treatment of colorectal liver metastases. AB - Forty patients with unresectable colorectal metastases confined to the liver were evaluated in a phase II study. 5-Fluorouracil (5-FU) was delivered via a surgically placed hepatic artery catheter. Patients received folinic acid (200 mg m-2) intravenously over 2 h followed by a loading dose of intra-arterial 5-FU (400 mg m-2) over 15 min, then 5-FU (1600 mg m-2) by intra-arterial infusion over the following 22 h. This was repeated on day 2 and the whole schedule was repeated every 2 weeks. Response was assessed after six treatments. The median follow-up was 17 months. Overall response rate was 46% with 8% complete response. Estimated median survival is 19 months. Site of progression was the liver alone in 55%, liver and lung in another 16% and 29% in other sites. Eight patients experienced grade 3 or 4 toxicity. The response rate of this regimen compares favourably with reported trials of intra-arterial FUDR, and our schedule is currently being compared with a similar schedule of intravenous 5-FU and folinic acid in a randomized Medical Research Council trial (CR05). PMID- 9374390 TI - The PAX gene egl-38 mediates developmental patterning in Caenorhabditis elegans. AB - Mutations in the C. elegans gene egl-38 result in a discrete set of defects in developmental pattern formation. In the developing egg-laying system of egl-38 mutant hermaphrodites, the identity of four uterine cells is disrupted and they adopt the fate of their neighbor cells. Likewise, the identity of two rectal epithelial cells in the male tail is disrupted and one of these cells adopts the fate of its neighbor cell. Genetic analysis suggests that the egl-38 functions in the tail and the egg-laying system are partially separable, as different egl-38 mutations can preferentially disrupt the different functions. We have cloned egl 38 and shown that it is a member of the PAX family of genes, which encode transcription factors implicated in a variety of developmental patterning events. The predicted EGL-38 protein is most similar to the mammalian class of proteins that includes PAX2, PAX5 and PAX8. The sequence of egl-38 mutant DNA indicates that the tissue-preferential defects of egl-38 mutations result from substitutions in the DNA-binding paired domain of the EGL-38 protein. egl-38 thus provides the first molecular genetic insight into two specific patterning events that occur during C. elegans development and also provides the opportunity to investigate the in vivo functions of this class of PAX proteins with single cell resolution. PMID- 9374391 TI - Cis-acting elements conserved between mouse and pufferfish Otx2 genes govern the expression in mesencephalic neural crest cells. AB - Previous studies suggested that the Otx2 gene plays an essential role in the development of cranial skeletons and nerves of mesencephalic neural crest origin. To clarify this role, we have identified the cis-acting elements in mouse and pufferfish Otx2 genes responsible for the expression in the crest cells using a transgenic approach with the lacZ reporter gene. In mouse, 49 bp sequences in the proximal 5' region upstream were essential and sufficient to direct the transgene expression in the cephalic mesenchyme. In pufferfish, the 1.1 kb distal region, located far downstream (from +14.4 to +15.5 kb), had almost identical activity. Between them, several DNA sequences were conserved, and mutational analyses indicated that motif A was critical for the transgene expression in the premandibular region while motif B was critical in both premandibular and mandibular regions. Motif B, CTAATTA, contains the core motif for binding of homeodomain proteins while motif A, TAAATCTG, does not match any known consensus binding sequences for transcriptional factors. The cephalic mesenchyme that expressed beta-galactosidase under these cis-elements is most likely to correspond to mesencephalic crest cells. Thus the molecular machinery regulating Otx2 expression in these cells appears to be conserved between mouse and fish, implying a crucial role of the Otx2 gene in development of the neural-crest derived structures of the gnathostome rostral head. PMID- 9374392 TI - Alveogenesis failure in PDGF-A-deficient mice is coupled to lack of distal spreading of alveolar smooth muscle cell progenitors during lung development. AB - PDGF-A(-/-) mice lack lung alveolar smooth muscle cells (SMC), exhibit reduced deposition of elastin fibres in the lung parenchyma, and develop lung emphysema due to complete failure of alveogenesis. We have mapped the expression of PDGF-A, PDGF receptor-alpha, tropoelastin, smooth muscle alpha-actin and desmin in developing lungs from wild type and PDGF-A(-/-) mice of pre- and postnatal ages in order to get insight into the mechanisms of PDGF-A-induced alveolar SMC formation and elastin deposition. PDGF-A was expressed by developing lung epithelium. Clusters of PDGF-Ralpha-positive (PDGF-Ralpha+) mesenchymal cells occurred at the distal epithelial branches until embryonic day (E) 15.5. Between E16.5 and E17.5, PDGF-Ralpha+ cells multiplied and spread to acquire positions as solitary cells in the terminal sac walls, where they remained until the onset of alveogenesis. In PDGF-A(-/-) lungs PDGF-Ralpha+ cells failed to multiply and spread and instead remained in prospective bronchiolar walls. Three phases of tropoelastin expression were seen in the developing lung, each phase characterized by a distinct pattern of expression. The third phase, tropoelastin expression by developing alveolar SMC in conjunction with alveogenesis, was specifically and completely absent in PDGF-A(-/-) lungs. We propose that lung PDGF-Ralpha+ cells are progenitors of the tropoelastin-positive alveolar SMC. We also propose that postnatal alveogenesis failure in PDGF-A(-/-) mice is due to a prenatal block in the distal spreading of PDGF-Ralpha+ cells along the tubular lung epithelium during the canalicular stage of lung development. PMID- 9374393 TI - Coordinate actions of BMPs, Wnts, Shh and noggin mediate patterning of the dorsal somite. AB - Shortly after their formation, somites of vertebrate embryos differentiate along the dorsoventral axis into sclerotome, myotome and dermomyotome. The dermomyotome is then patterned along its mediolateral axis into medial, central and lateral compartments, which contain progenitors of epaxial muscle, dermis and hypaxial muscle, respectively. Here, we used Wnt-11 as a molecular marker for the medial compartment of dermomyotome (the 'medial lip') to demonstrate that BMP in the dorsal neural tube indirectly induces formation of the medial lip by up regulating Wnt-1 and Wnt-3a (but not Wnt-4) expression in the neural tube. Noggin in the dorsal somite may inhibit the direct action of BMP on this tissue. Wnt-11 induction is antagonized by Sonic Hedgehog, secreted by the notochord and the floor plate. Together, our results show that the coordinated actions of the dorsal neural tube (via BMP and Wnts), the ventral neural tube/notochord (via Shh) and the somite itself (via noggin) mediates patterning of the dorsal compartment of the somite. PMID- 9374394 TI - The Caenorhabditis elegans NK-2 homeobox gene ceh-22 activates pharyngeal muscle gene expression in combination with pha-1 and is required for normal pharyngeal development. AB - Pharyngeal muscle development in the nematode Caenorhabditis elegans appears to share similarities with cardiac muscle development in other species. We have previously described CEH-22, an NK-2 class homeodomain transcription factor similar to Drosophila tinman and vertebrate Nkx2-5, which is expressed exclusively in the pharyngeal muscles. In vitro, CEH-22 binds the enhancer from myo-2, a pharyngeal muscle-specific myosin heavy chain gene. In this paper, we examine the role CEH-22 plays in pharyngeal muscle development and gene activation by (a) ectopically expressing ceh-22 in transgenic C. elegans and (b) examining the phenotype of a ceh-22 loss-of-function mutant. These experiments indicate that CEH-22 is an activator of myo-2 expression and that it is required for normal pharyngeal muscle development. However, ceh-22 is necessary for neither formation of the pharyngeal muscles, nor for myo-2 expression. Our data suggest parallel and potentially compensating pathways contribute to pharyngeal muscle differentiation. We also examine the relationship between ceh-22 and the pharyngeal organ-specific differentiation gene pha-1. Mutations in ceh-22 and pha 1 have strongly synergistic effects on pharyngeal muscle gene expression; in addition, a pha-1 mutation enhances the lethal phenotype caused by a mutation in ceh-22. Wild-type pha-1 is not required for the onset of ceh-22 expression but it appears necessary for maintained expression of ceh-22. PMID- 9374395 TI - Transcriptional regulation of breathless FGF receptor gene by binding of TRACHEALESS/dARNT heterodimers to three central midline elements in Drosophila developing trachea. AB - The development of Drosophila trachea is under the control of spatially and/or quantitatively regulated activity of BREATHLESS FGF receptor, which is also essential for midline glial migration. Here, we identified the minimum enhancer region of breathless, cloned the Drosophila ARNT gene (dARNT), and showed biochemical and genetic evidence that breathless expression in developing trachea is regulated by direct interactions between TRACHEALESS/dARNT heterodimers and three central midline elements (TACGTGs) situated in the minimum enhancer region. Our results also showed that SINGLE-MINDED/dARNT heterodimers, which are essential for breathless expression in midline precursor cells, share DNA targets in common with TRACHEALESS/dARNT, indicating that two different basic helix-loop helix-PAS protein complexes act through the same target sites in vivo. PMID- 9374396 TI - Hyaluronan is a prerequisite for ductal branching morphogenesis. AB - Hyaluronan, a macromolecular carbohydrate polymer of the extracellular matrix is prominent early in embryogenesis, coinciding with rapid tissue growth. CD44, the predominant receptor for hyaluronan on vertebrate cells, is a variably expressed transmembrane glycoprotein. Mouse anterior prostate glands obtained at various postnatal time points were examined for the expression of hyaluronan and CD44. Reverse transcriptase polymerase chain reaction analysis was used to map the temporal regulation of specific CD44 variant isoforms. In each age group, hyaluronan was localized exclusively in the stromal matrix. Hyaluronan was greatly reduced in the later ages and was entirely absent around the developmentally quiescent proximal regions of the ducts. Early in prostate development, CD44 was prominent in the mesenchyme. However, in the later phases, CD44 expression became associated with membranes of epithelial cells. The role of hyaluronan-CD44 interactions in ductal branching morphogenesis was studied by serum-free organ culture of mouse anterior prostate. In the presence of optimal levels of testosterone, the organs underwent ductal branching morphogenesis. Treatment with either neutralizing anti-CD44 antibodies, hyaluronan hexasaccharides or the enzyme hyaluronidase inhibited androgen-stimulated ductal branching morphogenesis. These results are suggestive of the significant role played by hyaluronan-CD44 interactions in mediating androgen-induced prostatic growth and morphogenesis. PMID- 9374397 TI - Polydactyly and ectopic ZPA formation in Alx-4 mutant mice. AB - Correct development of the limb is dependent on coordination between three distinct signaling centers. Recently, fibroblast growth factor-4 has been identified as a crucial determinant of AER function, which directs limb bud outgrowth, and Sonic hedgehog has been identified as a signaling molecule that mediates ZPA function, which specifies anterior-posterior patterning in the developing limb bud. In addition, Shh and FGF-4 reciprocally reinforce each other's expression via a positive feedback loop, providing a molecular basis for the coordination of limb bud outgrowth and anterior-posterior patterning. The mechanisms by which these signaling centers come to occupy their normal positions in the posterior limb bud during development are not understood. Here we identify and characterize Alx-4, a gene that encodes a paired-type homeodomain protein. Alx-4 is expressed in several populations of mesenchymal cells, including mesenchymal cells in the anterior limb bud, and mice homozygous for targeted disruption of the Alx-4 gene have multiple abnormalities, including preaxial polydactyly. The polydactyly is associated with the formation of an ectopic anterior ZPA, as indicated by anterior expression of Sonic hedgehog, HoxD13 and fibroblast growth factor-4. The expression of other candidate regulators of anterior-posterior positional information in the limb bud, including HoxB8 and Gli3, is not altered in Alx-4 mutant embryos. By chromosomal mapping experiments, Alx-4 is tightly linked to Strong's luxoid, a polydactylous mouse mutant. The results identify Alx-4 as a determinant of anterior-posterior positional identity in the limb and a component of a regulatory program that restricts ZPA formation to the posterior limb bud mesenchyme. PMID- 9374398 TI - Overexpression of FGF-2 modulates fiber cell differentiation and survival in the mouse lens. AB - During mammalian embryogenesis, the ocular lens forms through a temporally and spatially regulated pattern of differentiation which is thought to be coordinated at least in part by the FGF-1 and FGF-2 members of the fibroblast growth factor (FGF) family. Previous transgenic experiments in which FGF-1 or dominant negative FGF receptors were overexpressed in the lens indicated that FGF-1 could induce differentiation while differentiated lens cells rely upon FGF signaling for their survival. In this study, we asked if the 17.5 kDa FGF-2 protein was capable of inducing differentiation of lens cells in transgenic mice. Unexpectedly, differentiation was inhibited by lens-specific expression of a transgene encoding a secreted form of the 17.5 kDa bovine FGF-2 protein under the transcriptional control of the murine alphaA-crystallin promoter (alphaAIgFGF-2 transgenic mice). To address the possibility that FGF-2 functions as a modulator of fiber cell survival, alphaAIgFGF-2 transgenic mice were crossed to transgenic mice exhibiting extensive apoptosis in the lens due to the functional inactivation of the retinoblastoma protein (alphaAE7 transgenic mice). The level of apoptosis in the lenses of double transgenic mice was substantially reduced as compared to the level in lenses from alphaAE7 only mice. These studies indicate that FGF-2 can act as a modulator of the later stages of differentiation including fiber cell survival. Additionally, they imply that control of lens development by FGFs is a complex process in which FGF-1 and FGF-2 play distinct roles. PMID- 9374399 TI - The Danforth's short tail mutation acts cell autonomously in notochord cells and ventral hindgut endoderm. AB - Danforth's short tail (Sd) is a semidominant mutation in mouse affecting the axial skeleton and urogenital system. The notochord is the first visibly abnormal structure in mutant embryos, and disintegrates beginning around embryonic day 9.5 along its entire length, suggesting an essential role for Sd in notochord development and maintenance. Here, we report on the fate of Sd/+ and Sd/Sd cells in chimeric embryos. Up to day 9-9.5, Sd cells contributed efficiently to the notochord of chimeric embryos. In advanced day 9.5 embryos, Sd cells were less abundant in the posterior-most region of the notochord and in the notochordal plate. During subsequent development, Sd cells were specifically lost from the notochord and replaced by wild-type cells. In Sd/+<-->+/+ chimeras, the notochord appeared histologically and functionally normal, leading to a rescue of the mutant phenotype. However, strong Sd/Sd<-->+/+ chimeras showed malformations of the axial skeleton and urogenital system. All Sd/Sd<-->+/+ chimeras with malformations of the axial skeleton also had kidney defects, whereas chimeras without vertebral column defects had highly chimeric kidneys that appeared normal, suggesting that the urogenital malformations arise secondarily to impaired posterior development caused by the degenerating notochord. Sd mutant cells also were specifically absent from the ventral portion of the hindgut, whereas they contributed efficiently to the dorsal region, implying the existence of distinct cell populations in the dorsal and ventral hindgut. Our findings demonstrate that the Sd mutation acts cell autonomously in cells of the notochord and ventral hind gut. Sd leads to the degeneration of notochord cells and the number or allocation of notochord precursors from the tail bud to the notochordal plate seems impaired, whereas notochord formation from the node appears to be unaffected. PMID- 9374400 TI - Drosophila tissue polarity requires the cell-autonomous activity of the fuzzy gene, which encodes a novel transmembrane protein. AB - The tissue polarity gene fuzzy (fy) has two roles in the development of Drosophila wing hairs. One is to specify the correct orientation of the hair by limiting the site of prehair initiation to the distal vertex of the wing cell. The other is to control wing cell hair number by maintaining the integrity of the cytoskeletal components that direct hair development. The requirement for fy in these processes is temperature dependent, as the amorphic fy phenotype is cold sensitive. Analysis of mosaic wings has shown that the fy gene product functions cell autonomously. We have cloned the fy transcript, which encodes a novel four pass transmembrane protein that shares significant homology with proteins encoded by vertebrate cDNAs. The fourth putative transmembrane domain does not appear to play a significant role in tissue polarity as it is deleted in a weak fy hypomorph. Expression of the fy transcript is developmentally regulated and peaks sharply at the time of wing cell pre-hair initiation. PMID- 9374401 TI - The Drosophila gene Bearded encodes a novel small protein and shares 3' UTR sequence motifs with multiple Enhancer of split complex genes. AB - Gain-of-function alleles of the Drosophila gene Bearded (Brd) cause sensory organ multiplication and loss phenotypes indistinguishable at the cellular level from those caused by loss-of-function mutations in the genes of the Notch pathway (Leviten, M. W. and Posakony, J. W. (1996). Dev. Biol. 176, 264-283). We have carried out a molecular analysis of the structure and expression of both wild type and mutant Brd transcription units. We find that the Brd transcript is truncated and accumulates to substantially higher levels in the gain-of-function mutants, due to the insertion of a transposable element of the blood family in the Brd 3' untranslated region (UTR). The wild-type Brd 3' UTR includes three copies of a 9-nucleotide sequence (CAGCTTTAA) that we refer to as the 'Brd box'. Moreover, the 3' UTRs of Brd and of the m4 transcription unit of the Enhancer of split gene complex [E(spl)-C] exhibit an unusually high degree of sequence identity that includes not only Brd box sequences but also a second motif we refer to as the 'GY box' (GTCTTCC). We find that both the Brd box and the GY box are also present in the 3' UTRs of several basic helix-loop-helix repressor encoding genes of the E(spl)-C, often in multiple copies, suggesting that a novel mode of post-transcriptional regulation applies to Brd and many E(spl)-C genes. The fact that the more abundant Brd mutant mRNA lacks the GY box and two of the Brd boxes present in wild-type Brd mRNA suggests that either or both of these elements may confer instability on transcripts that contain them. Finally, we find that Brd encodes a novel small protein of only 81 amino acids that is predicted to include a basic amphipathic alpha-helix. The deduced Brd protein shows sequence similarity to the E(spl)m4 protein, which is likewise expected to include a basic amphipathic alpha-helix, suggesting that the two proteins have related biochemical functions. PMID- 9374402 TI - Smoothened-mediated Hedgehog signalling is required for the maintenance of the anterior-posterior lineage restriction in the developing wing of Drosophila. AB - It is thought that the posterior expression of the 'selector' genes engrailed and invected control the subdivision of the growing wing imaginal disc of Drosophila into anterior and posterior lineage compartments. At present, the cellular mechanisms by which separate lineage compartments are maintained are not known. Most models have assumed that the presence or absence of selector gene expression autonomously drives the expression of compartment-specific adhesion or recognition molecules that inhibit intermixing between compartments. However, our present understanding of Hedgehog signalling from posterior to anterior cells raises some interesting alternative models based on a cell's response to signalling. We show here that anterior cells that lack smoothened, and thus the ability to receive the Hedgehog signal, no longer obey a lineage restriction in the normal position of the anterior-posterior boundary. Rather these clones extend into anatomically posterior territory, without any changes in engrailed/invected gene expression. We have also examined clones lacking both en and inv; these too show complex behaviors near the normal site of the compartment boundary, and do not always cross entirely into anatomically anterior territory. Our results suggest that compartmentalization is a complex process involving intercompartmental signalling; models based on changes in affinity or growth will be discussed. PMID- 9374403 TI - Expression and interactions of the two closely related homeobox genes Phox2a and Phox2b during neurogenesis. AB - Recent evidence suggests that specific families of homeodomain transcription factors control the generation and survival of distinct neuronal types. We had previously characterized the homeobox gene Phox2a, which is expressed in differentiating neurons of the central and peripheral autonomic nervous system as well as in motor nuclei of the hindbrain. Targeted deletion of the Phox2a gene affects part of the structures in which it is expressed: the locus coeruleus, visceral sensory and parasympathetic ganglia and, as we show here, the nuclei of the IIIrd and IVth cranial nerves. We now report on the characterization of Phox2b, a close relative of Phox2a, with an identical homeodomain. Phox2a and Phox2b are co-expressed at most sites, therefore suggesting a broader role for Phox2 genes in the specification of the autonomic nervous system and cranial motor nuclei than revealed by the Phox2a knock-out mice. A detailed analysis of the relative timing of Phox2a and Phox2b expression at various sites suggests positive cross-regulations, which are substantiated by the loss of Phox2b expression in cranial ganglia of Phox2a-deficient mice. In the major part of the rhombencephalon, Phox2b expression precedes that of Phox2a and starts in the proliferative neuroepithelium, in a pattern strikingly restricted on the dorsoventral axis and at rhombomeric borders. This suggests that Phox2b links early patterning events to the differentiation of defined neuronal populations in the hindbrain. PMID- 9374404 TI - Glial-cell-line-derived neurotrophic factor is required for bud initiation from ureteric epithelium. AB - The shapes of different organs can be explained largely by two fundamental characteristics of their epithelial rudiments - the pattern of branching and the rate of proliferation. Glial-cell-line-derived neurotrophic factor (GDNF) has recently been implicated in the development of metanephric ureteric epithelium (Pichel, J. G., Shen, L., Sheng, H. Z., Granholm, A.-C., Drago, J., Grinberg, A., Lee, E. J., Huang, S. P., Saarma, M., Hoffer, B.J., Sariola, H. and Westphal, H. (1996). Nature 382, 73-76; Sanchez, M.P., Silos-Santiago, I., Frisen, J., He, B., Lira, S.A. and Barbacid, M. (1996). Nature 382, 70-73; Vega, Q.C., Worby, C.A., Lechner, M.S., Dixon, J.E. and Dressler, G.R. (1996). Proc. Nat. Acad. Sci. USA 93, 10657-10661). We have analysed the target cells of GDNF and the manner in which it controls ureteric development, and have compared it with other growth factors that have been associated with the regulation of branching morphogenesis, namely hepatocyte growth factor (HGF) and transforming growth factor-beta1 (TGFbeta1). We show that GDNF binds directly to the tips of ureteric bud branches, and that it has the ability to promote primary ureteric buds from various segments of Wolffian duct and to attract ureteric branches towards the source of GDNF. It increases cell adhesion, but is not obviously mitogenic for ureteric cells. The data indicate that GDNF is required primarily for bud initiation. Comparison of GDNF, HGF and TGFbeta1 suggests that the latter act later than GDNF, and may represent a partially redundant set of mesenchyme derived growth factors that control ureteric development. Thus, GDNF is the first defined inducer in the embryonic metanephric kidney. PMID- 9374405 TI - Retrospective clonal analysis of the cerebellum using genetic laacZ/lacZ mouse mosaics. AB - Analysis of lacZ neuronal clones in the mouse cerebellum demonstrates genealogical independence of the primary and secondary germinal epithelia (PGE and SGE) from early development. PGE precursors and their neuronal descendants are organised into two polyclonal groups of similar sizes that exhibit parasagittal patterning and generally respect the midline. The relationship between these two groups cannot be traced back in time to less than 80 independent cells, which were probably recruited following a period of non coherent growth that distributes unrelated cells into distinct territories of the neural tube. A lateromedial clonal organisation is observed in the mature cerebellum, suggesting the existence of many small parasagittal domains of clonal restriction and/or of cell dispersion in the rostrocaudal but not in the mediolateral dimension. The organisation is orthogonal with respect to the cellular organisation in the neural tube as is the genetic organisation. Cellular and genetic patterning of the cerebellum therefore share similarities. A possible hypothesis is that distinct cell behaviours create the different clonal domains observed in this study and that the cellular and genetic organisation of the cerebellum are coordinated. PMID- 9374406 TI - GATA-1 expression pattern can be recapitulated in living transgenic zebrafish using GFP reporter gene. AB - In this study, DNA constructs containing the putative zebrafish promoter sequences of GATA-1, an erythroid-specific transcription factor, and the green fluorescent protein reporter gene, were microinjected into single-cell zebrafish embryos. Erythroid-specific activity of the GATA-1 promoter was observed in living embryos during early development. Fluorescent circulating blood cells were detected in microinjected embryos 24 hours after fertilization and were still present in 2-month-old fish. Germline transgenic fish obtained from the injected founders continued to express green fluorescent protein in erythroid cells in the F1 and F2 generations. The green fluorescent protein expression patterns in transgenic fish were consistent with the pattern of GATA-1 mRNA expression detected by RNA in situ hybridization. These transgenic fish have allowed us to isolate, by fluorescence-activated cell sorting, the earliest erythroid progenitor cells from developing embryos for in vitro studies. By generating transgenic fish using constructs containing other zebrafish promoters and green fluorescent protein reporter gene, it should be possible to visualize the origin and migration of any lineage-specific progenitor cells in a living embryo. PMID- 9374407 TI - dally, a Drosophila glypican, controls cellular responses to the TGF-beta-related morphogen, Dpp. AB - Decapentaplegic (Dpp) is a Drosophila member of the Transforming Growth Factor beta (TGF-beta)/Bone Morphogenetic Protein (BMP) superfamily of growth factors. Dpp serves as a classical morphogen, where concentration gradients of this secreted factor control patterning over many cell dimensions. Regulating the level of Dpp signaling is therefore critical to its function during development. One type of molecule proposed to modulate growth factor signaling at the cell surface are integral membrane proteoglycans. We show here that division abnormally delayed (dally), a Drosophila member of the glypican family of integral membrane proteoglycans is required for normal Dpp signaling during development, affecting cellular responses to this morphogen. Ectopic expression of dally+ can alter the patterning activity of Dpp, suggesting a role for dally+ in modulating Dpp signaling strength. These findings support a role for members of the glypican family in controlling TGF-beta/BMP activity in vivo by affecting signaling at the cell surface. PMID- 9374408 TI - Sperm from beta 1,4-galactosyltransferase-null mice are refractory to ZP3-induced acrosome reactions and penetrate the zona pellucida poorly. AB - A variety of sperm surface components have been suggested to mediate gamete recognition by binding to glycoside ligands on the egg coat glycoprotein ZP3. The function of each of these candidate receptors is based upon varying degrees of circumstantial and direct evidence; however, the effects on fertilization of targeted mutations in any of these candidate receptors have not yet been reported. In this paper, we describe the effects of targeted mutations in beta1,4 galactosyltransferase, the best studied of the candidate receptors for ZP3. Surprisingly, galactosyltransferase-null (gt[-/-]) males are fertile; however, sperm from gt(-/-) males bind less radiolabeled ZP3 than wild-type sperm, and are unable to undergo the acrosome reaction in response to either ZP3 or anti galactosyltransferase antibodies, as do wild-type sperm. In contrast, gt(-/-) sperm undergo the acrosome reaction normally in response to calcium ionophore, which bypasses the requirement for ZP3 binding. The inability of gt(-/-) sperm to undergo a ZP3-induced acrosome reaction renders them physiologically inferior to wild-type sperm, as assayed by their relative inability to penetrate the egg coat and fertilize the oocyte in vitro. Thus, although ZP3 binding and subsequent induction of the acrosome reaction are dispensable for fertilization, they impart a physiological advantage to the fertilizing sperm. A second strain of mice was created that is characterized by a loss of of the long galactosyltransferase isoform responsible for ZP3-dependent signal transduction, but which maintains normal levels of Golgi galactosylation. Sperm from these mice show that the defective sperm-egg interactions in gt(-/-) mice are due directly to a loss of the long galactosyltransferase isoform from the sperm surface and are independent of the state of intracellular galactosylation during spermatogenesis. PMID- 9374409 TI - Involvement of RBP-J in biological functions of mouse Notch1 and its derivatives. AB - Notch is involved in the cell fate determination of many cell lineages. The intracellular region (RAMIC) of Notch1 transactivates genes by interaction with a DNA binding protein RBP-J. We have compared the activities of mouse RAMIC and its derivatives in transactivation and differentiation suppression of myogenic precursor cells. RAMIC comprises two separate domains, IC for transactivation and RAM for RBP-J binding. Although the physical interaction of IC with RBP-J was much weaker than with RAM, transactivation activity of IC was shown to involve RBP-J by using an RBP-J null mutant cell line. IC showed differentiation suppression activity that was generally comparable to its transactivation activity. The RBP-J-VP16 fusion protein, which has strong transactivation activity, also suppressed myogenesis of C2C12. The RAM domain, which has no other activities than binding to RBP-J, synergistically stimulated transactivation activity of IC to the level of RAMIC. The RAM domain was proposed to compete with a putative co-repressor for binding to RBP-J because the RAM domain can also stimulate the activity of RBP-J-VP16. These results taken together, indicate that differentiation suppression of myogenic precursor cells by Notch signalling is due to transactivation of genes carrying RBP-J binding motifs. PMID- 9374410 TI - Homophilic synaptic target recognition mediated by immunoglobulin-like cell adhesion molecule Fasciclin III. AB - We demonstrate that the cell adhesion molecule Fasciclin III (FAS3) mediates synaptic target recognition through homophilic interaction. FAS3 is expressed by the RP3 motoneuron and its target muscles during synaptic target recognition. The RP3 growth cone can form synapses on muscles that ectopically express FAS3. This mistargeting is dependent on FAS3 expression in the motoneurons. In addition, when the FAS3-negative aCC and SNa motoneuron growth cones ectopically express FAS3, they gain the ability to recognize FAS3-expressing muscles as alternative targets. We propose that homophilic synaptic target recognition serves as a basic mechanism of neural network formation. PMID- 9374411 TI - Patterning of the chick forebrain anlage by the prechordal plate. AB - We analysed the role of the prechordal plate in forebrain development of chick embryos in vivo. After transplantation to uncommitted ectoderm a prechordal plate induces an ectopic, dorsoventrally patterned, forebrain-like vesicle. Grafting laterally under the anterior neural plate causes ventralization of the lateral side of the forebrain, as indicated by a second expression domain of the homeobox gene NKX2.1. Such a lateral ventralization cannot be induced by the secreted factor Sonic Hedgehog alone, as this is only able to distort the ventral forebrain medially. Removal of the prechordal plate does not reduce the rostrocaudal extent of the anterior neural tube, but leads to significant narrowing and cyclopia. Excision of the head process results in the caudal expansion of the NKX2.1 expression in the ventral part of the anterior neural tube, while PAX6 expression in the dorsal part remains unchanged. We suggest that there are three essential steps in early forebrain patterning, which culminate in the ventralization of the forebrain. First, anterior neuralization occurs at the primitive streak stage, when BMP-4-antagonizing factors emanate from the node and spread in a planar fashion to induce anterior neural ectoderm. Second, the anterior translocation of organizer-derived cells shifts the source of neuralizing factors anteriorly, where the relative concentration of BMP-4 antagonists is thus elevated, and the medial part of the prospective forebrain becomes competent to respond to ventralizing factors. Third, the forebrain anlage is ventralized by signals including Sonic Hedgehog, thereby creating a new identity, the prospective hypothalamus, which splits the eye anlage into two lateral domains. PMID- 9374412 TI - The Drosophila 14-3-3 protein Leonardo enhances Torso signaling through D-Raf in a Ras 1-dependent manner. AB - 14-3-3 proteins have been shown to interact with Raf-1 and cause its activation when overexpressed. However, their precise role in Raf-1 activation is still enigmatic, as they are ubiquitously present in cells and found to associate with Raf-1 in vivo regardless of its activation state. We have analyzed the function of the Drosophila 14-3-3 gene leonardo (leo) in the Torso (Tor) receptor tyrosine kinase (RTK) pathway. In the syncytial blastoderm embryo, activation of Tor triggers the Ras/Raf/MEK pathway that controls the transcription of tailless (tll). We find that, in the absence of Tor, overexpression of leo is sufficient to activate tll expression. The effect of leo requires D-Raf and Ras1 activities but not KSR or DOS, two recently identified essential components of Drosophila RTK signaling pathways. Tor signaling is impaired in embryos derived from females lacking maternal expression of leo. We propose that binding to 14-3-3 by Raf is necessary but not sufficient for the activation of Raf and that overexpressed Drosophila 14-3-3 requires Ras1 to activate D-Raf. PMID- 9374413 TI - Bcl-2 is required for cranial sensory neuron survival at defined stages of embryonic development. AB - To ascertain the role of endogenous Bcl-2 in maintaining the survival of developing neurons and modulating their responses to neurotrophins, we compared the in vitro and in vivo survival of cranial sensory neurons of wild-type and bcl 2 null mouse embryos. At the peak of naturally occurring neuronal death in the trigeminal ganglion at E14, trigeminal neurons from bcl-2(-/-) embryos initially survived in culture in response to NGF but were not sustained as well as neurons from wild-type embryos. At the end of the period of naturally occurring neuronal death at E18, Bcl-2-deficient trigeminal neurons survived with NGF as well as wild-type neurons. At E14 in vivo, the number of trigeminal neurons undergoing apoptosis was significantly greater in bcl-2(-/-) embryos, and there were significantly fewer neurons in the trigeminal ganglia of bcl-2(-/-) embryos at E16 and E18. Similar age-related changes in the responses of nodose ganglion neurons to BDNF were observed in cultures established from bcl-2(-/-) and wild type embryos between E14 and E18. These results suggest that endogenous Bcl-2 is required for the sustained survival response of a subset of cranial sensory neurons to neurotrophins at particular stages of embryonic development and show that its absence leads to reduced numbers of these neurons in vivo. PMID- 9374414 TI - Is there a role for 15-lipoxygenase in atherogenesis? AB - 15-Lipoxygenase has been suggested to play a role in atherogenesis. The proposed action of this enzyme is to oxidize low density lipoprotein (LDL) to the extent that LDL becomes a ligand for the macrophage scavenger receptor. 15-Lipoxygenase and oxidized LDL are co-localized in atherosclerotic lesions; antioxidant drugs that block the lipoxygenase also block oxidation of LDL and the progression of experimental atherosclerosis. Biochemical experiments have demonstrated that the lipoxygenase can be induced by cytokines and/or another factor(s) associated with hypercholesterolemia. However, molecular biological work has shown that induction of the enzyme alone is not sufficient to induce lesion formation. Furthermore, the mechanism of action of 15-lipoxygenase in atherogenesis remains unclear. Predictions of the stereochemistry of enzyme-oxidized linoleate products appear to conflict with the available data. In fact, most studies have discovered substantial levels of racemic 13-hydroxyoctadecadienoic acid (13-HODE) in arterial lesions rather than the stereochemically pure 13(S)-HODE expected from purified enzyme. The possibility that the generation of products of 15 lipoxygenase metabolism must occur in a specific cellular location and during a brief time window in the development of the disease has been discussed. It is also possible that the true function of the linoleate metabolites is to modulate gene expression and regulate mitogenesis, and that oxidation of LDL may play a secondary role. The advent of transgenic species that both develop atherosclerosis and either fail to express or overexpress the lipoxygenase presents an opportunity to clarify some of these issues in the near future. PMID- 9374415 TI - Intracellular targets for antidiabetic sulfonylureas and potassium channel openers. AB - Antidiabetic sulfonylureas and potassium channel openers affect the activity of the ATP-regulated potassium channel (K(ATP) channel) present in the plasma membrane of various cells. This causes a broad spectrum of physiological responses, including the modulation of insulin release from pancreatic B-cells and the relaxation of smooth muscle. Recently, new targets for antidiabetic sulfonylureas and potassium channel openers were found in membranes of organelles, such as mitochondria and zymogen- and insulin-containing granules. By acting on these targets, the drugs modulate, independently of K(ATP) channel activity, insulin release from pancreatic B-cells, and they regulate K+ transport in mitochondria and zymogen granules. The interaction of sulfonylureas and potassium channel openers with intracellular targets gives additional basic information about their properties. Additionally, these studies could be important because of the medical applications of sulfonylureas and potassium channel openers. PMID- 9374416 TI - Characterization of two pituitary GH3 cell sublines partially resistant to apoptosis induction by okadaic acid. AB - Pituitary GH3 cells die by apoptosis when treated with okadaic acid, a specific inhibitor of ser/thr phosphatases. Incubations starting at concentrations of 5 and 12.5 nM followed by stepwise rises resulted in two populations (the S1 and S2 sublines) that proliferated at initially lethal 30 nM. Cells were partially resistant to higher concentrations of okadaic acid and its derivative methyl okadaate. Toxicity of the structurally distinct inhibitors cantharidic acid and calyculin A was differently affected in the two resistant lines. The enhanced expression of the P-glycoprotein was one mechanism of resistance in S1 and S2. Resistance was reversed completely (S1) or partially (S2) by the addition of verapamil. In addition, phosphatase activity, presumably PP2A, was increased in S2. Therefore, pharmacokinetic and pharmacodynamic mechanisms can protect pituitary GH3 cells from apoptotic cell death by okadaic acid. PMID- 9374417 TI - Protective effects of tea polyphenols against oxidative damage to red blood cells. AB - Tea polyphenols (TPP) from black and green teas were evaluated for their antioxidant effects on normal red blood cells (RBC) and beta-thalassemic RBC membranes challenged with exogenous oxidants in vitro. The TPP of both types protected RBC against primaquine-induced lysis; they also protected the whole cells and the membranes against H2O2-induced lipid peroxidation so that about 80% protection was reached at [TPP] = 10 microg/mL. TPP from black tea at the same concentration protected normal RBC from morphological alterations caused by the peroxide treatment. The mechanism of the effects of TPP was investigated using a chemical system generating .OH (iron + ascorbic acid). TPP from both black and green teas inhibited the .OH fluxes in a concentration-dependent manner, indicating the possibility of iron chelation by TPP. Spectrophotometric titration revealed that TPP could stoichiometrically bind ferric iron to form a redox inactive Fe-TPP complex. Quantitative analysis suggests that one or more major catechins from the TPP preparations are the likely iron-binding compounds accounting for the antioxidant effects of TPP on RBC. PMID- 9374418 TI - Intracellular metabolism of 3'-azido-3'-deoxythymidine (AZT): a nuclear magnetic resonance study on T-lymphoblastoid cell lines with different resistance to AZT. AB - This paper reports the results of 31P and 1H nuclear magnetic resonance (NMR) studies on the uptake and phosphorylation of 3'-azido-3'-deoxythymidine (AZT) in the human CD4+ T-lymphoblastoid cell line CCRF-CEM (CEM-1.3) and in its AZT resistant cell variant MT-500, isolated by prolonged culturing of CEM cells in the presence of increasing AZT concentrations. After 3 hr of incubation in the presence of 0.5 mM AZT, both AZT and its monophosphorylated form (AZT-MP) could be detected in the sensitive cell line in concentrations above the NMR detection levels. In another cell line, MOLT-4, which is less sensitive to AZT effects, the intracellular level of AZT-MP was much lower and was only slightly raised by increasing the concentration of AZT in the extracellular and intracellular compartments. In the AZT-resistant clone MT-500, characterized by a very low thymidine kinase (TK, EC 2.7.1.21) activity with respect to the parental clone, the intracellular AZT-MP concentration was below detection (<0.02 nmol/10(6) cells). Since, however, not only AZT-MP but also AZT signals failed to be detected in MT-500 extracts following cell incubation with AZT, it was concluded that a TK deficiency cannot be the exclusive mechanism of AZT resistance in these cells. The possible effects of additional mechanisms of drug resistance, such as specific AZT cell extrusion and limited permeation, are discussed, together with the new prospects offered by NMR spectroscopy to further evaluate the limiting steps for the utilization of antiretroviral nucleoside analogues. PMID- 9374419 TI - Specific inhibition of cardiac and skeletal muscle sarcoplasmic reticulum Ca2+ pumps by H-89. AB - The isoquinolinesulfonamide H-89, an inhibitor of cyclic AMP-dependent protein kinases (EC 2.7.1.37, cAPrK), inhibited the Ca2+-ATPase activity of cardiac and skeletal muscle sarcoplasmic reticulum (SR) with concentrations giving half maximal inhibition of 8.1 +/- 1.3 and 7.2 +/- 0.9 micromol/L, respectively. The effect of H-89 on cardiac SR Ca2+-ATPase (EC 3.6.1.38) was the same irrespective of the presence or absence of inhibitors of cAPrK and furthermore, was not affected by a neutralising monoclonal antibody raised against phospholamban. Thus, the action of H-89 in inhibiting SR Ca2+-ATPase would not appear to be mediated by inhibition of cAPrK to reduce the phosphorylation state of phospholamban. In both cardiac and skeletal muscle SR, the inhibition by H-89 was noncompetitive with respect to ATP at a low concentration of ATP (<1 mmol/L) and of a mixed pattern at high concentrations of ATP. H-89 produced a decrease in affinity of the SR Ca2+ pump to Ca2+ with an increase in the Km for Ca from 0.52 +/- 0.01 to 0.94 +/- 0.03 micromol/L (P < 0.05) in cardiac SR and from 0.39 +/- 0.01 to 0.79 +/- 0.02 micromol/L (P < 0.05) in skeletal muscle SR. These results suggest that H-89 inhibits SR Ca2+-ATPase by a direct action on the SR Ca2+ pump to decrease its affinity to Ca2+. Such an action may contribute to the pharmacological effect of H-89. PMID- 9374420 TI - 3-(13-Hydroxytridecyl)-1-[13-(3-pyridyl)tridecyl]pyridinium chloride (YM-53792), a novel inhibitor of NF-AT activation. AB - A compound, YM-53792, was identified as an inhibitor of interleukin-2 (IL-2) gene promoter activity, using a Jurkat cell-based reporter system in which the luciferase gene is regulated by the IL-2 gene promoter. Production of IL-2, interleukin-4 (IL-4) and interleukin-5 (IL-5) from human peripheral blood mononuclear cells was suppressed by YM-53792 in a dose-dependent fashion. Since expression of these cytokine genes is known to be regulated by NF-AT, we examined whether the promoter activity created by multimerization of NF-AT elements was inhibited with YM-53792. YM-53792 inhibited this promoter activity, but not AP-1- and NF-kappaB-driven promoter activities nor SV40 enhancer/promoter activity. In addition, electrophoretic mobility shift assays did not detect NF-AT/DNA complexes when nuclear extract prepared from YM-53792-treated, PMA/A23187 stimulated Jurkat cells was used, whereas AP-1/DNA complexes were observed. These results suggest that YM-53792 specifically inhibits the activation of NF-AT. PMID- 9374421 TI - Evidence for platelet-activating factor receptor subtypes on human polymorphonuclear leukocyte membranes. AB - Platelet-activating factor (PAF) is a potent phospholipid mediator that acts through specific cell surface receptors. The existence of PAF receptor subtypes has been suggested by functional and radioligand binding studies in a variety of cells and tissues. This report addresses this issue more directly and demonstrates differences between specific PAF receptors in human polymorphonuclear leukocytes (PMNs) and COS-7 cells transfected with the cloned human PAF receptor gene. The presence of more than one receptor in human PMNs is supported by three different studies. First, the Kd from the saturation isotherms for the binding of [3H]WEB 2086 on PMNs was 7-fold larger (Kd = 29.2 nM) than the kinetic Kd (4.2 nM). Second, the pseudo-Hill slope determined from the saturation experiments with PMNs was significantly lower than unity (0.69 +/- 0.05 SEM), and the saturation Kd values for transfected COS-7 (Kd = 9.6 nM) and PMN membranes were significantly different. These results contrasted with those for the transfected COS-7 cells, which showed a Kd from the saturation isotherms similar to that of the kinetic Kd (3.2 nM) and a pseudo-Hill slope that was not different from 1.0. Third, when the radiolabeled ligand [3H]WEB 2086 was increased in concentration from 10 to 50 nM in inhibition experiments with the human PMN membranes, the Ki increased, indicative of binding mainly to receptors with lower affinity. These results suggest that PAF receptor subtypes exist in human PMNs based on distinct radioligand binding characteristics from the human cloned PAF receptor. PMID- 9374422 TI - Studies on the inhibitory effects of quercetin on the growth of HL-60 leukemia cells. AB - Quercetin, a naturally occurring flavonoid, has been shown to exert multiple pharmacological effects and to be an anticancer agent or a supplementary anticancer agent. In this report, the human HL-60 promyelocytic leukemia cell line was used to study the effects of quercetin on the growth, cell cycle, activities of cytosolic and membrane protein kinase C (PKC) and tyrosine protein kinase (TPK), and phosphoinositide production of the tumor cells. The results showed that quercetin inhibited the growth of HL-60 cells in a concentration dependent manner, with an IC50 value of about 7.7 microM after 96 hr of treatment; when the concentration of quercetin was 10 microM, the percent inhibition on the growth of HL-60 cells was 17.1, 27.3, 40.1, and 52.7% after 24, 48, 72, and 96 hr of treatment, respectively. Flow cytometric analyses showed that quercetin caused an increase in cells in the G2/M phase and a decrease in cells in the G0/G1 phase of the cell cycle in a concentration-dependent manner; these effects were reversed when quercetin was removed from the culture medium. Quercetin strongly inhibited the activities of cytosolic PKC and membrane TPK from HL-60 cells in vitro, with IC50 values of about 30.9 and 20.1 microM, respectively, but did not affect membrane PKC or cytosolic TPK activity from HL 60 cells in vitro. Quercetin markedly inhibited in a concentration-dependent manner the production of phosphoinositides in intact HL-60 cells. The results provide evidence that the inhibitory effect of quercetin on the growth of HL-60 cells may be related to its inhibitory effects on PKC and/or TPK in vitro and/or on the production of phosphoinositides. PMID- 9374423 TI - Selective inhibition of collagen-induced arachidonic acid liberation by 1-(5 iodonaphthalene-1-sulphonyl)-1H-hexahydro-1,4-diazepine hydrochloride (ML-7), a myosin light chain kinase inhibitor, in washed rabbit platelets. AB - Effects of myosin light chain (MLC) kinase inhibitor ML-7 [1-(5-iodonaphthalene-1 sulphonyl)-1H-hexahydro-1,4-diazepine hydrochloride] and protein kinase C inhibitor H-7 [1-(5-isoquinolinesulphonyl)-2-methylpiperazine dihydro-chloride] on collagen-induced platelet activation were investigated in washed rabbit platelets. Upon stimulation with collagen (1 microg/mL), H-7 decreased protein kinase C-mediated pleckstrin phosphorylation, but had no inhibitory effect on thromboxane (TX) A2 formation or platelet aggregation. In contrast, ML-7 produced a concentration-dependent inhibition of the collagen-induced platelet aggregation and TXA2 formation by preventing arachidonic acid (AA) liberation from membrane phospholipids. However, ML-7 had little effect on AA liberation induced by thrombin, Ca2+ ionophore A-23187 or melittin, suggesting that ML-7 may affect the signal transduction pathway specific for collagen-induced AA liberation, without direct inhibition of phospholipase A2 activity. In indomethacin-treated platelets, collagen caused MLC phosphorylation and AA liberation in the absence of a significant increase in intracellular Ca2+ concentration ([Ca2+]i) or protein tyrosine phosphorylation. ML-7 inhibited both MLC phosphorylation and AA liberation induced by collagen in indomethacin-treated platelets. These results demonstrate that MLC phosphorylation and AA liberation are early events detectable in collagen-stimulated platelets, and suggest that ML-7 inhibits these early steps of collagen-induced signal transduction pathway in rabbit platelets. PMID- 9374424 TI - Analysis of GTP-binding proteins, phosphoproteins, and cytosolic calcium in functional heterogeneous human blood platelet subpopulations. AB - The biochemical basis for the functional heterogeneity of human blood platelets was investigated in terms of protein phosphorylation, cytoplasmic calcium ([Ca2+]i), the ratio of 46 and 50 kDa vasodilator-stimulated protein (VASP), and GTP-binding proteins (G-proteins). Platelets were fractionated by density. Comparing resting low-density platelets (LDP) to high-density platelets (HDP) revealed higher phosphorylation of proteins in the 47, 31, and 24 kDa ranges. A higher phosphorylation of the 20 kDa protein in LDP compared to HDP was related to an enhanced [Ca2+]i, an increased ADP-ribosylation of the inhibitory G-protein (G(i alpha1-3)) and rhoA, and a decreased ADP-ribosylation of the stimulatory G protein (G(s alpha)). The differences in the ribosylation patterns of the subpopulations were not influenced by thrombin stimulation or exposure to prostaglandin E1 (PGE1). An 18 kDa phosphoprotein was more highly phosphorylated in resting HDP than in LDP. Thrombin exposure caused dephosphorylation of the 18 kDa phosphoprotein in the HDP, but generally increased phosphorylation of both HDP and LDP in the 47, 31, 24, and 20 kDa bands. Preincubation with prostaglandin E1 or sodium nitroprusside diminished the subsequent thrombin-induced increase in phosphorylation, particularly in HDP. In unstimulated HDP, the 50 kDa VASP phospho form was enhanced, whereas in unstimulated LDP the 46 kDa VASP dephospho form was increased. Our findings suggest that the functional heterogeneity of platelets is partly derived from differences in signal transduction mechanisms reflected in varying phosphoprotein patterns and G-protein properties of platelet stimulatory and inhibitory pathways. PMID- 9374425 TI - Uptake of L-3,4-dihydroxyphenylalanine and dopamine formation in cultured renal epithelial cells. AB - In the presence of benserazide (50 microM), L-3,4-dihydroxyphenylalanine (L-DOPA) was rapidly accumulated in both LLC-PK1 and OK cells; equilibrium was attained at 30 min of incubation. For these LLC-PK1 and OK cells, the analysis revealed a rate constant of inward transport (k(in) in pmol/mg protein/min) of 3.6 +/- 0.4 and 18.1 +/- 0.3 and a rate constant of outward transport (k(out) in pmol/mg protein/min) of 1.0 +/- 0.1 and 5.2 +/- 0.1, respectively. Nonlinear analysis of the saturation curves for LLC-PK1 and OK cells revealed a Km (in microM) of 86 +/ 12 and 14 +/- 4, respectively. The cellular accumulation of the substrate was temperature-dependent and stereoselective. Aromatic L-amino acid decarboxylase (AAAD) activity was determined in cell homogenates; nonlinear analysis of the saturation curves revealed, for LLC-PK1 and OK cells, a Km (in microM) of 1866 +/ 107 and 845 +/- 153 and a Vmax (in nmol/mg protein/15 min) of 4.4 +/- 0.1 and 0.9 +/- 0.1, respectively. In the absence of benserazide, only a limited amount of the L-DOPA taken up was decarboxylated to dopamine in cell monolayers; the Km value (in microM) for decarboxylation of intracellular L-DOPA in LLC-PK1 and OK cells was 61 +/- 14 and 108 +/- 36, respectively. A low amount of newly formed dopamine was found to escape to the apical bathing fluid. This outward transfer of newly formed dopamine was a nonsaturable process up to 300 microM intracellular dopamine. In conclusion, the data presented here show that OK cells are endowed with a more efficient L-DOPA uptake system than LLC-PK1 cells, but the latter are endowed with a significantly higher AAAD activity than OK cells. In both cell lines, intracellular L-DOPA is rapidly converted to dopamine, some of which diffuses out of the cell. PMID- 9374426 TI - Inhibition of glutathione reductase by plant polyphenols. AB - The effects of forty-one plant polyphenols on the activity of glutathione reductase (GSH-RD) were studied. These polyphenols showed varying degrees of concentration-dependent inhibition on the enzyme, with IC50 values that varied from approximately 40 microM to 1 mM. 4'-Hydroxychalcone and tannic acid were among the more potent inhibitors, with IC50 values of 47.3 and 50.4 microM, respectively. Different classes of polyphenols varied in potency in the following order: chalcones > tannic acid > flavonoids > coumarins > catechins. Analysis of structure-activity relationships showed certain chemical structures to be important for the inhibition of GSH-RD: (a) C-5 and C-7 hydroxylations in the A ring, a carbonyl group at C-4, and the B-ring attached to C-2 in flavonoids; (b) C-2' and C-4' hydroxylations in chalcones; and (c) C-6 and C-7 hydroxylations in coumarins. The inhibition of GSH-RD by tannic acid and quercetin was time dependent and irreversible, whereas that by 4'-hydroxychalcone and esculin was reversible but not time dependent. Enhanced inhibition of GSH-RD by the four polyphenols 4'-hydroxychalcone, quercetin, butein, and acacetin was observed in the presence of NADPH. Kinetic studies showed that both tannic acid and 4' hydroxychalcone exhibited non-competitive inhibition on GSH-RD towards glutathione disulfide. PMID- 9374429 TI - LET dependence of cell death and chromatin-break induction in normal human cells irradiated by neon-ion beams. AB - We investigated the LET dependence of cell death and chromatin-break induction in normal human embryo cells irradiated by accelerated neon-ion beams. Neon-ion beams were generated by the Riken Ring Cyclotron (RRC) at the Institute of Physical and Chemical Research, Japan. Chromatin breaks were measured by counting the number of chromatin fragments detected by the premature chromosome condensation (PCC) technique. The results indicated that cell death and the induction of remaining chromatin breaks showed a qualitatively similar LET dependence. The LET RBE curves for both cell death and the induction of remaining chromatin breaks had a broad peak in the LET range of 120-300 keV/microm and steeply downward trend up to 340 keV/microm. These results suggest that there is a good correlation between cell death and the induction of remaining chromatin breaks by neon-ion beams with different LET values. PMID- 9374428 TI - Induction of micronuclei in respiratory tract following radon inhalation. AB - Male Wistar rats were exposed to radon and its progeny (0.0, 60, 262 and 564 working level months, WLM), and the frequency of micronuclei was determined in deep lung fibroblasts, and deep lung, trachea and nasal epithelial cells with slopes of 0.28, 0.67, 0.34 and 0.11 micronuclei/1000 binucleated cells/WLM respectively. Micronuclei in deep lung fibroblasts, isolated and cultured using two methods and media, demonstrated no differences in slopes. Biological damage was used as a biodosimeter to calculate the relationship between dosimetric units: alpha particle traversals or 'nuclear hits', dose in mGy and exposure in WLM. The estimated number of nuclear alpha traversals/Gy was 6.3. Radon exposure to 170 WLM resulted in the same frequency of micronuclei in deep lung epithelial cells as produced by one alpha hit/cell nucleus. Absorbed dose/unit of exposure (mGy/WLM) was estimated assuming the damage was related to absorbed dose or to changes in cell sensitivity and ranged from 1.13 to 1.34 for deep lung epithelial cells, 0.47 to 1.09 for deep lung fibroblasts, 0.34 to 0.67 for tracheal epithelial cells and 0.18 to 0.33 for nasal epithelial cells. Biological dosimetry can be used to relate exposure to damage, compare dosimetric units and validate physical dosimetry models. This approach can be applied to any inhaled material capable of producing biological damage. PMID- 9374430 TI - A Monte Carlo calculation of cell inactivation by light ions. AB - This study simulates the exposure of V79 Chinese hamster fibroblasts to low energy protons, deuterons and alpha-particles in the LET range 10-200 keV/microm. The starting assumption is that the induction of clustered lesions in DNA is a fundamental step for cell inactivation. A non-homogeneous cell population was simulated by a computer program, using as input measured morphological parameters reported in the literature. Variations in the number of traversals through each cell of the population and in the length of the traversal, depending on actual nuclear thickness and position of the traversal, the energy spread of the incident beam, and the change of LET along the tracks were included in the simulation. Microdosimetric spectra were computed and compared with spectra obtained neglecting particle slowing-down and stochastic aspects of cell morphology. Simulated cell survival was estimated under the assumption that surviving cells are those with no clustered DNA lesions or no passages. The main features of experimental RBE versus LET and particle type were reproduced by the simulations. The influence of stochastic aspects of target-cell morphology and of the energy of the incident particles on survival were investigated under different assumptions about the correlation between morphological parameters. Results support the hypothesis of a relevant role of clustered DNA damage in cell killing and point out the importance of target-cell morphology and its variability in beam dosimetry and computer simulations of low-energy particle radiation effects. PMID- 9374427 TI - Inhibition by pulmonary surfactant Curosurf of secretory phospholipase A2 expression in guinea-pig alveolar macrophages. AB - Replacement therapy with exogenous surfactant has been proven successful in animal models of acute respiratory distress syndrome (ARDS). Here, we investigated the effect of seminatural surfactant Curosurf on the expression of secretory phospholipase A2 (sPLA2) in guinea-pig alveolar macrophages (AM). The latter produced an sPLA2 activity whose level was markedly reduced when culture medium was supplemented with Curosurf. This effect was concentration-dependent and was accompanied by a decrease in sPLA2 mRNA levels. By contrast, when AM were first cultured for 20 hr and then incubated with Curosurf, no significant change was observed in their sPLA2 activity. Finally, f-Met-Leu-Phe (FMLP)-induced thromboxane B2 release from AM was not altered by Curosurf, indicating that the inhibition of sPLA2 expression cannot be attributed to a nonspecific membraneous effect of Curosurf. These findings show that pulmonary surfactant modulates the expression of sPLA2 in AM and suggest that this effect may account for the clinical efficacy of surfactant replacement therapy in ARDS. PMID- 9374431 TI - Radiation-induced transformation of SV40-immortalized human thyroid epithelial cells by single exposure to plutonium alpha-particles in vitro. AB - Human thyroid carcinomas have been induced following exposure of SV40 immortalized human thyroid epithelial cells in vitro to single doses (0.14 Gy to 1.57 Gy) of 3.26 MeV alpha-particles from a plutonium 238 source. Tumours were detected between 50 and 160 days following subcutaneous transplantation of the irradiated cells in athymic mice. No tumours were observed following transplantation of unirradiated cells. The relative biological effectiveness (RBE) of the alpha-particles, estimated from cell survival curves, was 4.8 at 50% survival and 3.3 at 5% survival. A first estimate of the RBE at peak tumour induction was 3.8. This system provides a means of studying the mechanisms of tumourigenesis in human thyroid epithelial cells induced by ionizing radiations, including tumours induced by single alpha particles such as from environmental natural radon and polonium and artificial plutonium and americium, and those induced by beta- or Auger-emissions from particular iodine isotopes. PMID- 9374432 TI - Alpha-particle-induced neoplastic transformation in synchronized hybrid cells of HeLa and human skin fibroblasts. AB - Survival and oncogenic transformation frequencies were determined through the cell cycle in hybrid cells (HeLa x human skin fibroblasts), exposed to 0.30 and 0.15 Gy 4.3 MeV (LET= 101 keV/microm) alpha-particles. The cells were synchronized by mitotic collection and irradiated at times ranging from 2 to 10 h after collection, corresponding to G1 and early S. At 0.30 Gy the highest value in the transformation frequency (1.6 +/- 0.3) x 10(-4) transformants/survivor, occurred 4 h after mitotic collection, corresponding to mid-G1 and was about twice as high as that for the asynchronous population (0.7 +/- 0.1) x 10(-4) transformants/survivor. A similar pattern was seen at 0.15 Gy albeit less marked. The results are similar to previous findings with C3H10T1/2 exposed to 0.30 Gy where (1.8 +/- 0.4) x 10(-4) and (0.8 +/- 0.4) x 10(-4) transformants/survivor were found in mid-G1 and in the asynchronous population respectively. The results of both these studies with 101 keV/microm alpha particles indicate that mid-G1 cells may be more sensitive than asynchronous cells by up to a factor of two. However, it is unlikely that such a factor is sufficient to represent the cell cycle 'hot spot' for transformation postulated to explain the inverse dose-rate effect. PMID- 9374433 TI - Low dose-rate X-irradiation induces larger deletions at the human HPRT locus than high dose-rate X-irradiation. AB - PURPOSE: To investigate the size of deletions induced by low dose-rate (LDR) X irradiation in relation to the induction by high dose-rate (HDR) X-irradiation at the HPRT locus of human lymphoblastoid WI-L2-NS cells. MATERIALS AND METHODS: The molecular nature of HPRT deletions in human WI-L2-NS lymphoblasts was investigated after LDR or HDR X-irradiation with a total dose of 4 Gy using a set of nine Xq26 sequence tagged sites (STS loci) markers surrounding the hprt gene and covering approximately 2.75 Mb. RESULTS: Eleven of 24 LDR X-ray-induced mutants contained a deletion of the entire hprt gene, whereas this was the case in 10 of 19 HDR X-irradiation-induced mutants. Most of the LDR and HDR total gene deletions exhibited also loss of markers adjacent to the HPRT locus, 10/11 and 7/10 respectively. The largest HDR X-irradiation induced deletion was 0.89 Mb, while the largest deletion observed after LDR X-irradiation (4/11 HPRT deletion mutants) extended outside the investigated region in both proximal (> 0.57 Mb) and distal directions (> 2 Mb). CONCLUSIONS: The average size of HPRT deletions after LDR X-irradiation was significantly larger (p = 0.0024) than following HDR, suggesting that an inverse dose-rate effect exists for the size of deletions induced by X-irradiation. PMID- 9374434 TI - Increased sensitivity of scid heterozygous mice to ionizing radiation. AB - In the present study, acute effects of ionizing radiation on animal survival, bone marrow cells and fibroblast cell lines of scid homozygous, scid heterozygous and wild-type mice with the same C.B-17 genetic background were examined. The sensitivities to ultraviolet light (UV) and various chemicals, bleomycin, mitomycin C, N-methyl-N'-nitro-N-nitrosoguanidine, methyl methanosulphonate, 5 fluorouracil, 6-mercaptopurine, 4-nitroquinoline 1-oxide and potassium bromate) were also investigated. In addition, micronucleus testing of whole-body irradiated mice was performed. Scid heterozygous mice were found to be less sensitive than the homozygotes but more sensitive to ionizing radiation than wild type mice, not only in vivo but also for bone marrow cells in vitro, suggesting partial dominance under both conditions. In contrast, there were no differences in sensitivity to UV light and various chemicals, as compared with wild-type and scid heterozygous cell lines, either in vitro or in the micronucleus test. PMID- 9374435 TI - Influence of ionizing radiation on proliferation, c-myc expression and the induction of apoptotic cell death in two breast tumour cell lines differing in p53 status. AB - PURPOSE: To determine the capacity of ionizing radiation to inhibit proliferation, to suppress c-myc expression and to induce apoptotic cell death in the p53 wild-type MCF-7 cell line and the p53 mutated MDA-MB231 cell line. MATERIALS AND METHODS: Growth inhibition and cell killing were determined by cell number and trypan blue exclusion. Apoptosis was assessed through cell morphology and fluorescent end-labelling. c-myc expression was monitored by Northern blotting. RESULTS: Inhibition of cell proliferation by ionizing radiation was similar in both cell lines. MDA-MB231 cells accumulated in G2 while MCF-7 cells accumulated in both the G1 and G2 phases of the cell cycle after irradiation. There was no evidence of apoptosis in either cell line. In MCF-7 cells, growth inhibition correlated closely with an early dose-dependent suppression of c-myc expression; in MDA-MB231 cells, there was no correspondence between growth inhibition and a transient, dose-independent reduction in c-myc message. CONCLUSIONS: These findings suggest that in the absence of classical apoptotic cell death, radiosensitivity is not predictably related to the p53 status of the cell. While both p53 and c-myc may be linked to the DNA damage response pathway, neither p53 nor c-myc are essential for growth arrest in response to ionizing radiation. PMID- 9374436 TI - Haemopoietic injury after irradiation: analysis of dose responses and repair using a target-cell model. AB - Published dose-incidence data for haemopoietic lethality in mice have been analysed using a mathematical model based on target-cell survival. The analysis of three comprehensive data sets produced an initial D(o) value of about 1.4 Gy, decreasing to about 1.1 Gy at 3 Gy, 0.9 Gy at 5 Gy, and about 0.7 Gy at a dose of 10 Gy. The alpha/beta ratio was about 14 Gy, and the repair half-time was about 0.3 h. The level of target-cell depletion at LD37 was at about 6 x 10(-4). The D(o) values are compatible with those measured directly for several stages of early haemopoietic progenitor cells in the marrow. The additional use of 13 or alternatively 24 other less-comprehensive data sets increased the overall degree of heterogeneity, so flattening dose-response curves and increasing the deduced overall D(o) values by a factor of about 2. However, when these data sets were stratified with respect to ln(N(o)) where N(o) is the number of tissue rescuing units (TRU), the results were comparable to those obtained when the three comprehensive data sets were analysed individually. Also, the repair halftime was higher at about 1 h. Further, the implied radiosensitivity of the projected target-cell population comprising the TRU was similar to the survival curves obtained for CFU-S and other closely-related haemopoietic progenitor cell types. It has been shown that the number of critical TRU at risk in the marrow is the main feature modulating heterogeneity even when it is assumed that the cellular radiosensitivity does not vary between strains. The number of stem cells comprising a TRU may vary between strains and this may also be influenced by environmental and/or immunological factors. However, it is certainly the case that the initial complement of TRU plays a major role in the incidence of whole body radiation induced mortality. PMID- 9374437 TI - Peripheral blood lymphocyte decrease and micronucleus yields during radiotherapy. AB - PURPOSE: To investigate the relationship between lymphocyte decrease and cytogenetic response in individual patients undergoing radiotherapy. MATERIALS AND METHODS: Peripheral blood lymphocytes obtained from 35 patients with pelvic and from 14 with head and neck tumours before and during radiotherapy were PHA stimulated in vitro and the cultures prepared for the cytokinesis-block micronucleus test. For some patients only, the micronucleus test was carried out after 2 Gy in vitro X-irradiation, and 3-aminobenzamide (2 mM) was used to calculate the 3AB-index. RESULTS: The initially observed individual variation in the decrease of lymphocytes disappeared with increasing number of radiation exposures, reaching a stable level at about 500/microl lymphocytes in the blood. The slope of the relationship between the reciprocal of the lymphocyte decrease ratio and equivalent dose indicates the radiosensitivity of the lymphocyte pool in individual patients. The micronucleus test performed on lymphocytes obtained from patients during radiotherapy (in vivo) provided a lower cytogenetic response than the in vitro micronucleus yield for the same dose, so it was possible to calculate the cytogenetic recovery factor k. A correlation was found between the 3AB-index calculated before radiotherapy, and the recovery factor k. CONCLUSIONS: The 3AB-index, the micronucleus frequency after 2 Gy in vitro X-irradiation, and the cytogenetic recovery factor are proposed as predictive of individual response to radiotherapy. PMID- 9374438 TI - Magnetic isotope effects in biology: a marker for radical pair reactions and electromagnetic field effects? AB - PURPOSE: To explore the possible usefulness of magnetic isotope effects, especially to detect processes affected by magnetic fields. MATERIALS AND METHODS: The theoretical model of Brocklehurst and McLauchlan is used to estimate the effects of isotopic substitution (e.g. 13C for 12C) on the yields of chemical reactions involving radical pairs. RESULTS: It is demonstrated that in some circumstances isotope effects on the yields from initially singlet pairs (bond breaking to give radicals) could be very large and easily detected. The effects on radical pairs formed by random encounters are necessarily much smaller but may be detectable. Illustrative calculations are presented for carbon, hydrogen and oxygen isotopes; deuterium substitution also produces very large mass effects but its study could be useful to support work on carbon. CONCLUSIONS: Effects may be small but worth looking for: distinguishing them from mass effects will be aided by measuring distributions within product molecules. In laboratory experiments (especially tomography) a combination of isotopic substitution and applied fields is a potentially powerful technique. PMID- 9374439 TI - Survival of human epithelial cells irradiated with cobalt 60 as microcolonies or single cells. AB - Microcolonies of one to >50 cells were irradiated. They were assayed for survival using the Puck and Marcus clonogenic technique and the distant progeny were tested for expression of lethal mutations. The results show that epithelial cell colonies appear to respond as a unit rather than as individual cells to a radiation dose and the uncorrected initial surviving fraction is relatively constant irrespective of the number of cells present at the time the microcolony was irradiated. Irradiation of colonies or monolayers, which were then dispersed, confirmed this and showed slight sparing of the cells irradiated in contact compared with single cells but no sparing effect when the gap junctions were closed. Measurement of apoptosis 2 h post-irradiation showed higher levels in clones derived from cells irradiated in contact but delayed apoptosis in the progeny and lethal mutations appear to be associated with irradiation of single cells. Lethal mutations occurred in the progeny of cells irradiated as single cells for at least 30 cell generations but if cell microcolonies were irradiated the progeny survival showed a complex relationship with progenitor dose. When gap junction intercellular communication (GJIC) was blocked during and immediately post-irradiation using nitrosamines or TPA, cultures regained the initial survival and lethal mutation frequency seen with single cells. It is concluded that the presence of more than one cell in a microcolony at the time of irradiation does result in an altered and possibly a co-ordinated pattern of survival and lethal mutation expression but that inhibition of GJIC can reverse the effects of contact. The results may have implications for investigations of normal tissue response. PMID- 9374440 TI - Increase in DNA single-strand break rejoining by continuous exposure of human mononuclear blood cells to radioiodine ((131)I) in vitro. AB - Radioiodine ((131)I) induced a dose- and time-dependent increase in DNA single strand breaks (DNA-ssb) in human (G0) mononuclear blood cells (MNC) in vitro. Incubation of MNC with 22MBq (131)I/ml at 4 degrees C caused a linear, time dependent induction of DNA-ssb (increase in elution rate: 24.7 x 10(-3) h(-1) per 100 min incubation with (131)I). However, if MNC were incubated at 37 degrees C a decrease in the slope of the time effect curve was observed after about 300 min incubation with 22 or 30 MBq (131)I/ml. The goodness of fit of different regression models was assessed by Akaike's Information Criterion (AIC). The best fit was obtained for a non-linear model (y=a+bx+cx(0.5); AIC=53.5; where x is incubation time and y is elution rate), whereas other models including the linear regression model y=a+bx; AIC=38.6) were worse. As the total induction of DNA-ssb at 4 degrees C was constant with time, the decrease in the slope of the time effect curve (DNA-ssb versus time) at 37 degrees C can be interpreted as an increase in rejoining of DNA-ssb. Inhibition of both RNA and protein synthesis clearly increased the extent of DNA-ssb observable after incubation with (131)I. Thus, during continuous exposure of MNC to (131)I, proteins were synthesized which rejoined DNA-ssb. However, incubation of MNC with (131)I (44 MBq/ml) at 37 degrees C under conditions expected to lead to inhibition of RNA and/or protein synthesis still resulted in a decrease of the slope of the time effect curve, indicating a stimulation of DNA-ssb rejoining. Thus, we favour the hypothesis that the increase in the activity of DNA-ssb rejoining, besides de novo synthesis of repair enzymes, is also caused by a post-translational stimulation of DNA repair enzymes and that this stimulation possibly is mediated by DNA-fragments. PMID- 9374442 TI - Recent EULEP dosimetry intercomparisons for whole body irradiation of mice. European Late Effects Project group. AB - PURPOSE: To foster quality assurance of dosimetry among the institutes involved in joint studies on late effects of ionizing radiation. MATERIALS AND METHODS: The participants in the dosimetry intercomparison received for each facility two mouse phantoms loaded with LiF thermoluminescent dosemeters (TLD) and a control badge. The participants were requested to irradiate the test phantoms in the actual arrangement used for whole body irradiation of mice, such that the dose in the centre of the test phantoms was 2 Gy and the dose distribution was uniform. The readout of the TLD and the dose evaluation were made at the organizing institute. RESULTS: Ten institutes operating 14 exposure facilities in four countries took part in the intercomparison. For one facility a dose deviation between 5 and 10% was found, whereas for two others the deviation exceeded 10%. The requirement for uniform dose distribution in a mouse phantom was not fulfilled by six exposure facilities. The causes for the dose discrepancies were found for two participants whereas for one participant the problems were only partly resolved. Non-uniform dose distributions are mainly related to unilateral irradiations. CONCLUSION: The seven EULEP dosimetry intercomparisons clearly show the need for quality assurance of dosimetry in radiobiology. PMID- 9374441 TI - Muscarinic receptor stimulation increases tolerance of rat salivary gland function to radiation damage. AB - PURPOSE: To investigate if muscarinic receptor-stimulated activation of the PLC/PIP2 second messenger pathway prior to irradiation increases the radiotolerance of rat salivary gland. MATERIALS AND METHODS: Rats were treated with pilocarpine, methacholine, reserpine, methacholine plus reserpine, or atropine prior to irradiation with a single dose of 15 Gy X-rays. Parotid and submandibular/sublingual saliva was collected 4 days before and 1-30 days after irradiation. Lag phase, flow rate, amylase secretion, and salivary sodium and potassium concentration were measured. RESULTS: Pretreatment with pilocarpine or methacholine resulted in an improvement of all measured functions of both glands. Pretreatment with reserpine had no effect on parotid gland function. Reserpine plus methacholine did not increase parotid gland function when compared with methacholine alone, indicating a purely muscarinic receptor stimulation as the initiator for the induced radioprotection. Pretreatment protective effects on submandibular gland function of reserpine plus methacholine were additive, indicating cooperation of muscarinic and alpha-adrenergic receptors. Atropine pretreatment slightly increased the radiation induced loss of salivary gland function. CONCLUSIONS: Preirradiation activation of PLC/PIP2 second messenger pathway through stimulation of muscarinic receptors reduces the salivary gland radiosensitivity. The observed protection of salivary gland function may be of a secondary nature, implicating a cell conditioning after receptor stimulation of the PLC/PIP2 pathway. PMID- 9374443 TI - Systematic isolation of circulating human peptides: the concept of peptide trapping. AB - The structural determination of circulating human peptides is essential to determine their correct posttranslationally processed form. Human hemofiltrate from patients with end stage renal disease is accessible in large quantities and is used as a source for the preparation of circulating peptides. After complete peptide extraction from hemofiltrate, a systematic separation with different chromatographic techniques is achieved. Single peptides are selected according to their mass and chromatographic elution position. Following chromatographic purification, amino acid sequence analysis is performed in combination with data base search. The identification of circulating peptides leads to numerous fragments resulting from cleavage of larger plasma proteins as well as to the discovery of new peptide hormones. The results obtained so far give insight into the degradation of plasma proteins such as fibrinogen, which results in the generation of fragments with biological activity themselves and in the identification of a novel cytokine HCC-1, the first member of beta-defensins in humans, hBD-1, and different peptides not present in any data base. PMID- 9374444 TI - Time discrete, near infrared photoplethysmography (NIRP) for non-invasive investigation of the volume pulse in man. AB - In pulse oximetry the principles of photoplethysmography are used for determination of heart rate and in some devices to also display the volume pulse. It has been suggested, that a more detailed analysis of the signal may allow quantitative analysis of peripheral hemodynamic events. We describe a new computer assisted time discrete analysis of the volume pulse, studying its reliability and the method s fundamental assumption of a linear relationship between changes in amplitude and changes in time sequences of the volume pulse. METHOD: In a finger clip two diodes emit near infrared (840 nm, NIR) and red light (640nm, RED) into the finger tip, where it is remitted mainly by the erythrocytes. 70 sec of recorded signal is filtered and the resulting volume pulse analysed off-line using a computer. On each volume pulse the time of the first (Tmax), the second maximum (time of dicrote, Td) and the duration of the volume pulse (Tp) are measured and the mean values displayed. In addition, the fundamental arterial oscillation Tag = Td - Tmax and all the above values in relation to Tp are calculated. Using NIRP, 54 healthy young volunteers (19 female, mean age 27.0 +/- 3.4 years) were studied and the individual mean values calculated from 960 measurements. The reliability during 10 repetitive measurements was investigated in 26 of the 54 volunteers. In 12 subjects 5 repetitive measurements were obtained from each finger and compared with each other. In 11 subjects the linear relationship between amplitude and time sequence was tested on > 30 000 single volume pulses. The finger clip photoelectrode was levelled with the right atrium in all measurements, skin close to the clip and room temperature were recorded. RESULTS: From the mean individual values the following time discrete values were calculated for the NIR signal (n = 41): Tp = 882.3 +/- 142.6 ms, Tmax = 214.8 +/- 28.3 ms, Td = 452.7 +/- 32.4 ms, Tdec = 667.4 +/- 133.6 ms, Tag = 237.9 +/- 36.3 ms, Tmax/Tdec = 0.34 +/- 0. 07, Td/Tdec = 0.7 +/- 0.11. For each parameter the individual standard deviation during 10 repetitive measurements (26 subjects) ranged between 2.2 and 6.1%. The time sequences found were not significantly different between the individual fingers. A linear relationship between changes in time sequence and changes in amplitude was found in all tested subjects (mean r = 0.96). CONCLUSION: These results show, that the values obtained with time discrete NIRP are highly reproducible and show an individual SD of less than 6.5% under steady state conditions. The linear relationship between time sequence and amplitude found in the present study has to be confirmed in further studies on patients with pathologies of the macro- and microcirculation. PMID- 9374445 TI - Demonstration of interleukin-1beta and interleukin-6 in cells of synovial fluids by flow cytometry. AB - Cytokine levels are increased in the synovial fluid of affected joints from patients with inflammatory joint diseases. The aim of our study was therefore to determine if and to what extent immmunologically defined subpopulations of mononuclear cells (MNC) in the synovial fluid are responsible for the increased levels of interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) in affected joints. Lipopolysaccharide (LPS) stimulated peripheral MNC were used as positive controls. While soluble IL-1beta (median 167 pg/ml) and IL-6 (median 508 pg/ml) levels were significantly elevated in the synovial fluids tested, IL-1beta and IL 6 were demonstrated by flow cytometry in only a small subpopulation (<=11%) of mononuclear synovial fluid cells in 7/13 patients. Our results suggest that elevated IL-1beta and IL-6 levels in the synovial fluid of inflammatory joints are derived mainly from cells in the synovial membrane and only to a minor extent from cells in the synovial fluid itself. PMID- 9374446 TI - TNF-alpha mediated apoptosis of CD4 positive T-lymphocytes. A model of T-cell depletion in HIV infected individuals. AB - Apoptosis has been suggested to account for loss of CD4+ T-cells in HIV infected individuals. Aside from MHC II dependent superantigens no mediator for preferential apoptosis of CD4+ T-cell has been described. However, the expression of TNF-alpha is increased in HIV+ patients. Additionally, TNF-alpha is known as a potent inducer of apoptosis in a variety of cell types. We therefore investigated the capacity of TNF-alpha to mediate apoptosis in vitro preferentially in CD4+ T cells from HIV+ individuals. In the presence of TNF-alpha, CD4+ T-cells from HIV+ individuals with more than 200 CD4+ T-cells/microl (classified CDC A1, A2, B1, B2) could be significantly depleted by apoptosis without a reduction of CD8+ T cells. In cells from patients with less than 100 CD4+ T-cells/microl (classified CDC C3), TNF-alpha mediated apoptosis was not apparent due to an already immensely elevated rate of apoptosis observed in the absence of TNF-alpha. Here we demonstrate cord blood mononuclear cells as a model for apoptosis since these cells develop apoptosis at a similar rate as that of PBMC in HIV+ patients. More than 50% of TNF-alpha stimulated CD4+ cord blood T-cells were depleted within 3 days by apoptosis, whereas CD8+ T-cells, B-cells and NK-cells were not affected. In PBMC from healthy adults, a preferential loss of CD4+ T-cells mediated by TNF alpha was not observed. A reduced production of IFN-gamma was observed in mononuclear cells from newborns and from HIV+ patients. Moreover, IFN-gamma and IL-2 could prevent TNF-alpha mediated apoptosis. Therefore, a reduced Th1-cell function may contribute to TNF-alpha mediated apoptosis of CD4+ T-cells from these donor groups. Taken together, the data suggest that TNF-alpha probably is a mediator of the loss of CD4+ T-cells in HIV infected patients in vivo. PMID- 9374447 TI - Acute renal failure following cardiac surgery is reverted by administration of Urodilatin (INN: Ularitide). AB - Acute renal failure (ARF) is a serious complication following cardiac surgery. This first controlled study was undertaken to verify, if Urodilatin (URO) infusion can revert incipient oliguric ARF after cardiac surgery. We conducted a randomized, double blind trial comparing 7 URO (20 ng/kg/min) with 7 placebo patients. Inclusion criterion was oliguria/anuria (< 0.5 ml/kg/hour) refractory to conventional treatment including administration of dopamine and furosemide. No patient in the URO treated group, but 6 patients in the placebo group had to be hemofiltered or hemodialyzed (p < 0.005) during the 7 day treatment period. In the URO group all 7 patients demonstrated a rapid recovery of diuresis after 2 - 8 hours of treatment that persisted throughout the treatment period. In contrast, placebo treated patients remained oliguric. Serum creatinine (SC) decreased in URO treated patients. No adverse effects were observed during URO administration. After termination of URO, 2 patients underwent hemodialysis for elevated blood urea nitrogen (BUN) values. In the postoperative follow-up period of 60 days, 4 out of 7 placebo treated patients died while still on hemodialysis. In contrast, all URO patients survived. URO is an effective drug to reverse oliguric ARF following cardiac surgery. Prolonged renal failure and renal replacement therapy can be avoided. PMID- 9374448 TI - A patient with hypoparathyroidism, dysmorphic features and mental retardation. AB - There have been various reports in the medical literature concerning children with syndromes of congenital hypoparathyroidism, seizures, dysmorphic features and mental retardation. We describe a patient with hypoparathyroidism, mental retardation, micrognathia, deep-set eyes and pes cavus in a 31-year-old man. This combination of abnormalities in an adult is unique. PMID- 9374449 TI - Cellular signaling in the bladder. AB - Embryologically, the urinary bladder is formed from endodermally derived epithelial cells and mesenchymal cells from the urogenital sinus and allantois. Experimentally, we have shown that bladder mesenchyme differentiates into bladder smooth muscle via an unknown signaling mechanism that originates from the urothelium. It is hypothesized that this signaling between the cellular types, occurs via growth factors. Evidence supporting this hypothesis is that a number of known growth factors, such as TGF beta 2 and 3, KGF and TGF alpha, as well as their receptors are regulated as a function of bladder development and are also modulated during experimental bladder outlet obstruction. Furthermore, growth factors most likely affect extracellular matrix degradative proteins which play a role in bladder remodeling during development, as well as in partial outlet obstruction. There is certainly impressive cellular communication that occurs during development and also occurs postnatally; such as during bladder injury. We have recently shown that KGF is directly responsible for the proliferation of urothelium during bladder injury. This normally quiescent cell, which in humans turns over once every six months to a year when injured, has the incredible ability to immediately proliferate covering the exposed areas of bladder muscle and submucosa. This proliferation is due to the direct effects of KGF, a classic paracrine growth factor which is secreted by the stromal compartment of the bladder and acts directly on the urothelium which harbors the receptor. The bladder also has an uncanny ability to regenerate. In a model to study the basic science behind bladder regeneration, a partial cystectomy was performed and an acellular tissue matrix devoid of all cellular elements was sutured to the defect. Within four days, the urothelium completely covered the acellular matrix, and within two weeks native smooth muscle was seen streaming into the acellular matrix in association with a new epithelium. It is hypothesized that cellular interactions between the epithelium and the mesenchyme, as we have shown in bladder differentiation, are encouraging the new growth of smooth muscle. For the bladder to be a safe and effective storage chamber the ideal cellular lining should be urothelium. Cells from the gastrointestinal are not optimal for this purpose since they either secrete or absorb electrolytes. We believe that the cellular interactions that occur between the urothelium and the foreign intestinal stroma will in time change the phenotype of the urothelium. Newer strategies for bladder replacement which take into account cellular signaling are critical for our young patients with neurogenic bladder disorders. PMID- 9374450 TI - Thermohaline circulation, the achilles heel of our climate system: will man-made CO2 upset the current balance? AB - During the last glacial period, Earth's climate underwent frequent large and abrupt global changes. This behavior appears to reflect the ability of the ocean's thermohaline circulation to assume more than one mode of operation. The record in ancient sedimentary rocks suggests that similar abrupt changes plagued the Earth at other times. The trigger mechanism for these reorganizations may have been the antiphasing of polar insolation associated with orbital cycles. Were the ongoing increase in atmospheric CO2 levels to trigger another such reorganization, it would be bad news for a world striving to feed 11 to 16 billion people. PMID- 9374451 TI - Late pliocene faunal turnover in the turkana basin, kenya and ethiopia AB - Analysis of a large sample of well-dated fossil mammals from localities in the Turkana Basin of Kenya and Ethiopia revealed sampling biases that affect patterns of faunal turnover during the late Pliocene. When these biases were accounted for, results indicated that 58 to 77 percent of the mammal species were replaced between 3.0 and 1.8 million years ago (Ma). Overall diversity increased from 3.0 to 2.0 Ma but then declined. No distinct turnover pulse is seen between 2.8 and 2.5 Ma; instead, the most significant period of faunal change began after 2.5 Ma and continued through 1.8 Ma. PMID- 9374452 TI - Platinum-group element abundance patterns in different mantle environments AB - Mantle-derived xenoliths from the Cameroon Line and northern Tanzania display differences in their platinum-group element (PGE) abundance patterns. The Cameroon Line lherzolites have uniform PGE patterns indicating a homogeneous upper mantle over several hundreds of kilometers, with approximately chondritic PGE ratios. The PGE patterns of the Tanzanian peridotites are similar to the PGE systematics of ultramafic rocks from ophiolites. The differences can be explained if the northern Tanzanian lithosphere developed in a fluid-rich suprasubduction zone environment, whereas the Cameroon Line lithosphere only experienced melt extraction from anhydrous peridotites. PMID- 9374453 TI - Transitions between blocked and zonal flows in a rotating annulus with topography AB - The mid-latitude atmosphere is dominated by westerly, nearly zonal flow. Occasionally, this flow is deflected poleward by blocking anticyclones that persist for 10 days or longer. Experiments in a rotating annulus used radial pumping to generate a zonal jet under the action of the Coriolis force. In the presence of two symmetric ridges at the bottom of the annulus, the resulting flows were nearly zonal at high forcing or blocked at low forcing. Intermittent switching between blocked and zonal patterns occurs because of the jet's interaction with the topography. These results shed further light on previous atmospheric observations and numerical simulations. PMID- 9374454 TI - Reversible polymers formed from self-complementary monomers using quadruple hydrogen bonding. AB - Units of 2-ureido-4-pyrimidone that dimerize strongly in a self-complementary array of four cooperative hydrogen bonds were used as the associating end group in reversible self-assembling polymer systems. The unidirectional design of the binding sites prevents uncontrolled multidirectional association or gelation. Linear polymers and reversible networks were formed from monomers with two and three binding sites, respectively. The thermal and environmental control over lifetime and bond strength makes many properties, such as viscosity, chain length, and composition, tunable in a way not accessible to traditional polymers. Hence, polymer networks with thermodynamically controlled architectures can be formed, for use in, for example, coatings and hot melts, where a reversible, strongly temperature-dependent rheology is highly advantageous. PMID- 9374455 TI - Two-dimensional melting of an anisotropic crystal observed at the molecular level AB - A distinctive two-dimensional (2D) melting transition occurring at nearly 100 degrees Celsius ( degrees C) has been observed in Langmuir-Blodgett films by in situ atomic force microscopy (AFM). A 2D orthorhombic crystal phase melted to a 2D smectic phase at about 91 degrees C. The smectic phase was characterized by 1D molecular periodicity with short-range correlations (about 40 angstroms). At 95 degrees C, the smectic order melted to form a hexatic phase. Infrared spectroscopy measurements were consistent with the AFM observations. These observations support the dislocation-mediated melting scenario for an anisotropic 2D crystal predicted by Ostlund and Halperin. A longer wavelength height modulation was also observed in the smectic and hexatic phases. PMID- 9374456 TI - Enhanced intergrain tunneling magnetoresistance in half-metallic CrO2 films AB - Low-field tunneling magnetoresistance was observed in films of half-metallic CrO2 that were grown by high-pressure thermal decomposition of CrO3. High-temperature annealing treatments modified the intergrain barriers of the as-grown films through surface decomposition of CrO2 into insulating Cr2O3, which led to a threefold enhancement of the low-field magnetoresistance. This enhancement indicates the potential of this simple method to directly control the interface barrier characteristics that determine the magnetotransport properties. PMID- 9374457 TI - Imaging of intermittency in ripple-wave turbulence AB - The dynamics of a fluid surface filled with high-amplitude ripples were studied with a technique (diffusing light photography) that resolves the height at all locations instantaneously. Even when nonlinearities are strong enough to generate a (Kolmogorov) cascade from long wavelength (where energy is input) to shorter wavelength, the resulting turbulent state contains large coherent spatial structures. The appearance of these structures in a thermal equilibrium state (with the same average energy) would be highly improbable. PMID- 9374458 TI - IRAK (Pelle) family member IRAK-2 and MyD88 as proximal mediators of IL-1 signaling. AB - The interleukin-1 receptor (IL-1R) signaling pathway leads to nuclear factor kappa B (NF-kappaB) activation in mammals and is similar to the Toll pathway in Drosophila: the IL-1R-associated kinase (IRAK) is homologous to Pelle. Two additional proximal mediators were identified that are required for IL-1R-induced NF-kappaB activation: IRAK-2, a Pelle family member, and MyD88, a death domain containing adapter molecule. Both associate with the IL-1R signaling complex. Dominant negative forms of either attenuate IL-1R-mediated NF-kappaB activation. Therefore, IRAK-2 and MyD88 may provide additional therapeutic targets for inhibiting IL-1-induced inflammation. PMID- 9374459 TI - Modulating irrelevant motion perception by varying attentional load in an unrelated task. AB - Lavie's theory of attention proposes that the processing load in a relevant task determines the extent to which irrelevant distractors are processed. This theory was tested by asking participants in a study to perform linguistic tasks of low or high load while ignoring irrelevant visual motion in the periphery of the display. Although task and distractor were unrelated, both functional imaging of motion-related activity in cortical area V5 and psychophysical measures of the motion aftereffect showed reduced motion processing during high load in the linguistic task. These findings fulfill the prediction that perception of irrelevant distractors depends on the relevant processing load. PMID- 9374460 TI - Spatial pattern formation in an insect host-parasitoid system AB - Spatial models in ecology predict that populations may form patchy distributions within continuous habitats, through strong predator-prey or host-parasitoid interactions combined with limited dispersal. Empirical support of these models is provided. Parasitoids emanating from a population outbreak of tussock moths (Orgyia vetusta) suppressed the growth of nearby experimental populations of the moth, while experimental populations farther away were able to grow. This result explains the observed localized nature of tussock moth outbreaks and illustrates how population distributions can be regulated by dynamic spatial processes. PMID- 9374461 TI - The spatial dimension in population fluctuations AB - Theoretical research into the dynamics of coupled populations has suggested a rich ensemble of spatial structures that are created and maintained either by external disturbances or self-reinforcing interactions among the populations. Long-term data of the Canadian lynx from eight Canadian provinces display large scale spatial synchrony in population fluctuations. The synchronous dynamics are not time-invariant, however, as pairs of populations that are initially in step may drift out of phase and back into phase. These observations are in agreement with predictions of a spatially-linked population model and support contemporary population ecology theory. PMID- 9374462 TI - Requirement for Valpha14 NKT cells in IL-12-mediated rejection of tumors. AB - A lymphocyte subpopulation, the Valpha14 natural killer T (NKT) cells, expresses both NK1.1 and a single invariant T cell receptor encoded by the Valpha14 and Jalpha281 gene segments. Mice with a deletion of the Jalpha281 gene segment were found to exclusively lack this subpopulation. The Valpha14 NKT cell-deficient mice could no longer mediate the interleukin-12 (IL-12)-induced rejection of tumors. Although the antitumor effect of IL-12 was thought to be mediated through natural killer cells and T cells, Valpha14 NKT cells were found to be an essential target of IL-12, and they mediated their cytotoxicity by an NK-like effector mechanism after activation with IL-12. PMID- 9374463 TI - CD1d-restricted and TCR-mediated activation of valpha14 NKT cells by glycosylceramides. AB - Natural killer T (NKT) lymphocytes express an invariant T cell antigen receptor (TCR) encoded by the Valpha14 and Jalpha281 gene segments. A glycosylceramide containing alpha-anomeric sugar with a longer fatty acyl chain (C26) and sphingosine base (C18) was identified as a ligand for this TCR. Glycosylceramide mediated proliferative responses of Valpha14 NKT cells were abrogated by treatment with chloroquine-concanamycin A or by monoclonal antibodies against CD1d/Vbeta8, CD40/CD40L, or B7/CTLA-4/CD28, but not by interference with the function of a transporter-associated protein. Thus, this lymphocyte shares distinct recognition systems with either T or NK cells. PMID- 9374464 TI - Defective TNF-alpha-induced apoptosis in STAT1-null cells due to low constitutive levels of caspases. AB - Signal transducers and activators of transcription (STATs) enhance transcription of specific genes in response to cytokines and growth factors. STAT1 is also required for efficient constitutive expression of the caspases Ice, Cpp32, and Ich-1 in human fibroblasts. As a consequence, STAT1-null cells are resistant to apoptosis by tumor necrosis factor alpha (TNF-alpha). Reintroduction of STAT1alpha restored both TNF-alpha-induced apoptosis and the expression of Ice, Cpp32, and Ich-1. Variant STAT1 proteins carrying point mutations that inactivate domains required for STAT dimer formation nevertheless restored protease expression and sensitivity to apoptosis, indicating that the functions of STAT1 required for these activities are different from those that mediate induced gene expression. PMID- 9374465 TI - Independent photoreceptive circadian clocks throughout Drosophila. AB - Transgenic Drosophila that expressed either luciferase or green fluorescent protein driven from the promoter of the clock gene period were used to monitor the circadian clock in explanted head, thorax, and abdominal tissues. The tissues (including sensory bristles in the leg and wing) showed rhythmic bioluminescence, and the rhythms could be reset by light. The photoreceptive properties of the explanted tissues indicate that unidentified photoreceptors are likely to contribute to photic signal transduction to the clock. These results show that autonomous circadian oscillators are present throughout the body, and they suggest that individual cells in Drosophila are capable of supporting their own independent clocks. PMID- 9374466 TI - The filamentous phage pIV multimer visualized by scanning transmission electron microscopy. AB - A family of homomultimeric outer-membrane proteins termed secretins mediates the secretion of large macromolecules such as enzymes and filamentous bacteriophages across bacterial outer membranes to the extracellular milieu. The secretin encoded by filamentous phage f1 was purified. Mass determination of individual molecules by scanning transmission electron microscopy revealed two forms, a unit multimer composed of about 14 subunits and a multimer dimer. The secretin is roughly cylindrical and has an internal diameter of about 80 angstroms, which is large enough to accommodate filamentous phage (diameter of 65 angstroms). PMID- 9374467 TI - Nuclear accumulation of NFAT4 opposed by the JNK signal transduction pathway. AB - The nuclear factor of activated T cells (NFAT) group of transcription factors is retained in the cytoplasm of quiescent cells. NFAT activation is mediated in part by induced nuclear import. This process requires calcium-dependent dephosphorylation of NFAT caused by the phosphatase calcineurin. The c-Jun amino terminal kinase (JNK) phosphorylates NFAT4 on two sites. Mutational removal of the JNK phosphorylation sites caused constitutive nuclear localization of NFAT4. In contrast, JNK activation in calcineurin-stimulated cells caused nuclear exclusion of NFAT4. These findings show that the nuclear accumulation of NFAT4 promoted by calcineurin is opposed by the JNK signal transduction pathway. PMID- 9374469 TI - Minireview series on enzyme superfamilies PMID- 9374470 TI - Evolutionary divergence of substrate specificity within the chymotrypsin-like serine protease fold. PMID- 9374468 TI - Independent and additive effects of central POMC and leptin pathways on murine obesity. AB - The lethal yellow (AY/a) mouse has a defect in proopiomelanocortin (POMC) signaling in the brain that leads to obesity, and is resistant to the anorexigenic effects of the hormone leptin. It has been proposed that the weight reducing effects of leptin are thus transmitted primarily by way of POMC neurons. However, the central effects of defective POMC signaling, and the absence of leptin, on weight gain in double-mutant lethal yellow (AY/a) leptin-deficient (lepob/lepob) mice were shown to be independent and additive. Furthermore, deletion of the leptin gene restored leptin sensitivity to AY/a mice. This result implies that in the AY/a mouse, obesity is independent of leptin action, and resistance to leptin results from desensitization of leptin signaling. PMID- 9374471 TI - The type I interferon receptor mediates tyrosine phosphorylation of the CrkL adaptor protein. AB - Interferon (IFN) alpha induces rapid and transient tyrosine phosphorylation of the Src homology 2/Src homology 3 (SH2/SH3)-containing CrkL adaptor protein in a time- and dose-dependent manner. Such phosphorylation is most likely regulated by the Type I interferon receptor (IFNR)-associated Tyk-2 kinase, as suggested by the detection of Type I IFN-dependent tyrosine kinase activity in anti-CrkL immunoprecipitates and the IFNalpha-dependent association of CrkL with Tyk-2 in intact cells. Two other Type I IFNs, IFNbeta and IFNomega, also induce tyrosine phosphorylation of CrkL, suggesting that the protein is involved in the signaling pathways of several different Type I IFNs. In the IFNalpha-sensitive U-266 and Daudi cell lines, CrkL interacts via its N terminus SH3 domain with the guanine exchange factor C3G that regulates activation of Rap-1, a small G-protein that exhibits tumor suppressor activity. Thus, tyrosine phosphorylation of CrkL links the functional Type I IFNR complex to the C3G-Rap-1 signaling cascade that mediates growth inhibitory responses. PMID- 9374472 TI - Cytochrome c-dependent and -independent induction of apoptosis in multiple myeloma cells. AB - Cytochrome c is a mitochondrial protein that induces apoptosis when accumulated in the cytosol in response to diverse stress inducers. This protein has also been shown to cause apoptosis when added to cell free extracts. In this report, we studied the role of cytochrome c (cyto-c) in dexamethasone (Dex), anti-Fas monoclonal antibody (mAb), and ionizing radiation-induced apoptosis in multiple myeloma cells. The results demonstrate that ionizing radiation-induced apoptosis is associated with an increase in cytosolic cyto-c levels, whereas apoptosis induced by Dex or anti-Fas mAb has no detectable effect on cyto-c release. By contrast, caspase-3 was activated in response to all of these agents. Thus, our findings suggest that Dex or anti-Fas mAb-induced apoptosis is not accompanied by cyto-c release and that there are at least two different pathways leading to activation of caspases and induction of apoptosis in multiple myeloma cells that can be distinguished by accumulation of cytosolic cyto-c. PMID- 9374473 TI - The role of the buried aspartate of Escherichia coli thioredoxin in the activation of the mixed disulfide intermediate. AB - The structurally homologous protein disulfide isomerases and thioredoxins exhibit a 10(5) variation of redox equilibria. It is demonstrated that the kinetic distinction among these protein family members lies primarily in the rate of breakdown of the mixed disulfide intermediate. The conserved buried acid group serves as a proton transfer catalyst for the buried active site cysteine in the formation and breakdown of the mixed disulfide. The reduction rate of Escherichia coli thioredoxin by dithiothreitol is directly proportional to the fraction of Asp-26 in the protonated form over the pH range of 6-9. The kinetic role of Asp 26 is further probed via differential solvent kinetic isotope effect measurements versus a D26N variant. The differential solvent isotope effect of 0.6 is consistent with a direct proton donation to the thiolate leaving group (Cys-35) via an enforced general acid catalysis by trapping mechanism. Such a donation necessitates a structural rearrangement as these two buried side chains are separated by 6 A in both the oxidized and reduced forms of the protein. PMID- 9374474 TI - Aspartate substitutions establish the concerted action of P-region glutamates in repeats I and III in forming the protonation site of L-type Ca2+ channels. AB - Hydrogen ions reduce ion flux through voltage-gated Ca2+ channels by binding to a single protonation site with an unusually high pKa. Recent evidence localizes the protonation site to the same locus that supports high affinity Ca2+ binding and selectivity, a set of four conserved glutamate residues near the external mouth of the pore. Remaining controversy concerns the question of whether the protonation site arises from a single glutamate, Glu-1086 (EIII), or a combination of Glu-1086 and Glu-334 (EI) working in concert. We tested these hypotheses with individual Glu --> Asp substitutions. The Glu --> Asp replacements in repeats I and III stood out in two ways. First, in both EID and EIIID, protonation was destabilized relative to wild type, whereas it was unchanged in EIID and stabilized in EIVD. The changes in affinity were entirely due to alterations in H+ off-rate. Second, the ratio of protonated conductance to deprotonated conductance was significantly closer to unity for EID and EIIID than for wild-type channels or other Asp mutants. Both results support the idea that EI and EIII act together to stabilize a single titratable H+ ion and behave nearly symmetrically in influencing pore conductance. Neutralization of EIII by alanine replacement clearly failed to abolish susceptibility to protonation, indicating that no single glutamate was absolutely required. Taken together, all the evidence supports a model in which multiple carboxylates work in concert to form a single high affinity protonation site. PMID- 9374475 TI - Isolation of a cDNA coding for L-galactono-gamma-lactone dehydrogenase, an enzyme involved in the biosynthesis of ascorbic acid in plants. Purification, characterization, cDNA cloning, and expression in yeast. AB - L-Galactono-gamma-lactone dehydrogenase (EC 1.3.2.3; GLDase), an enzyme that catalyzes the final step in the biosynthesis of L-ascorbic acid was purified 1693 fold from a mitochondrial extract of cauliflower (Brassica oleracea, var. botrytis) to apparent homogeneity with an overall yield of 1.1%. The purification procedure consisted of anion exchange, hydrophobic interaction, gel filtration, and fast protein liquid chromatography. The enzyme had a molecular mass of 56 kDa estimated by gel filtration chromatography and SDS-polyacrylamide gel electrophoresis and showed a pH optimum for activity between pH 8.0 and 8.5, with an apparent Km of 3.3 mM for L-galactono-gamma-lactone. Based on partial peptide sequence information, polymerase chain reaction fragments were isolated and used to screen a cauliflower cDNA library from which a cDNA encoding GLDase was isolated. The deduced mature GLDase contained 509 amino acid residues with a predicted molecular mass of 57,837 Da. Expression of the cDNA in yeast produced a biologically active protein displaying GLDase activity. Furthermore, we identified a substrate for the enzyme in cauliflower extract, which co-eluted with L-galactono-gamma-lactone by high-performance liquid chromatography, suggesting that this compound is a naturally occurring precursor of L-ascorbic acid biosynthesis in vivo. PMID- 9374476 TI - Dual specificity of the interleukin 1- and tumor necrosis factor-activated beta casein kinase. AB - Tumor necrosis factor (TNF) and interleukin 1 (IL1) activate a protein kinase, TIP kinase, which phosphorylates beta casein in vitro. We have now identified its main phosphorylation site on beta casein, Ser124 (Km approximately 28 mu M), and a minor phosphorylation site, Ser142 (Km approximately 0.7 mM). The sequence motif that determined the phosphorylation of Ser124 by the kinase was studied with synthetic peptides bearing deletions or substitutions of the neighboring residues. This allowed synthesis of improved substrates (Km approximately 6 mu M) and showed that efficient phosphorylation of Ser124 was favored by the presence of large hydrophobic residues at positions +1, +9, +11, and +13 (counted relative to the position of the phosphoacceptor amino acid) and of a cysteine at position 2. Peptides in which Ser124 was replaced by tyrosine were also phosphorylated by TIP kinase, showing it to have dual specificity. It is unable to phosphorylate the MAP kinases in vitro and is therefore not directly involved in their activation. Its biochemical characteristics indicate that TIP kinase is a novel dual specificity kinase, perhaps related to the mixed lineage kinases. It copurified with a phosphoprotein of about 95 kDa, which could correspond either to the autophosphorylated kinase or to an associated substrate. PMID- 9374477 TI - Inhibition of the transcription of CYP1A1 gene by the upstream stimulatory factor 1 in rabbits. Competitive binding of USF1 with AhR.Arnt complex. AB - A xenobiotic-responsive element (XRE)-binding factor(s) other than the AhR.Arnt complex was found to inhibit the transcription of CYP1A1 gene in the liver from adult rabbits, known to be nonresponsive to CYP1A1 inducers. The constitutive factor(s) in liver nuclear extracts bound to the core sequence of XRE. The binding was eliminated by the presence of an excess amount of the AhR.Arnt complex synthesized in vitro. To identify the constitutive factor(s), a sequence similar to rabbit XRE was sought. It was found that the sequence of rabbit XRE overlapped with that of the upstream stimulatory factor 1 (USF1)-binding site in the mouse metallothionein I promoter. In fact, a super shift assay using a specific antibody against human USF1 indicated that USF1 was capable of binding to rabbit XRE. Additionally, the AhR.Arnt-mediated activation of XRE-TK/Luc reporter gene in RK13 cells was blocked by the transfection with a USF1 expression vector with the amounts of the expression vector transfected. These results indicate that the XRE of the rabbit CYP1A1 gene is recognized by the basic helix-loop-helix proteins to regulate the expression of CYP1A1 in both an agonistic (AhR.Arnt) and an antagonistic (USF1) manner. PMID- 9374478 TI - Amino acid sequences of metalloendopeptidases specific for acyl-lysine bonds from Grifola frondosa and Pleurotus ostreatus fruiting bodies. AB - The complete amino acid sequences of two lysine-specific zinc metalloendopeptidases (EC 3.4.24), Grifola frondosa metalloendopeptidase (GFMEP) and Pleurotus ostreatus metalloendopeptidase (POMEP), from the fruiting bodies of these two edible mushrooms have been established based on the sequence information of the peptides generated from the reduced and alkylated GFMEP and POMEP by proteolytic digestions using GFMEP, trypsin, and other proteinases as well as by several chemical cleavages. From the sequences, it was found that GFMEP and POMEP were polypeptides composed of 167 and 168 amino acid residues, from which their molecular weights were calculated to be 18,040.5 and 17,921.3 in accord with the observed (M+H)+ values of 18,028 and 17,927, respectively, as determined by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Two disulfide bonds in GFMEP were found to link Cys5 to Cys75 and Cys77 to Cys97. An unusual post-translational modification of GFMEP was corroborated to be a partial attachment of a single mannose to Thr42. Comparison of the sequences revealed that overall identity between the enzymes was 61.3%. Although a highly homologous sequence was not found in sequence data bases except for a consensus zinc-binding sequence, HEXXH, both metalloendopeptidases somewhat resembled a family of metalloproteinases categorized as deuterolysin. These proteases together with GFMEP and POMEP do not have conserved third and/or fourth liganding amino acid residues seen in metzincin or thermolysin superfamily proteins and belong to a novel zinc metalloendopeptidase superfamily. PMID- 9374479 TI - Hepatitis C virus E2 protein purified from mammalian cells is frequently recognized by E2-specific antibodies in patient sera. AB - The envelope protein of hepatitis C virus (HCV) is composed of two membrane associated glycoproteins, E1 and E2. To obtain HCV E2 protein as a secretory form at a high level, we constructed a recombinant chinese hamster ovary (CHO) cell line expressing a C-terminal truncated E2 (E2t) fused to human growth hormone (hGH), CHO/hGHE2t. The hGHE2t fusion protein was purified from the culture supernatant using anti-hGH mAb affinity chromatography at approximately 80% purity. The purified hGHE2t protein appeared to be assembled into oligomers linked by intermolecular disulfide bond(s) when density gradient centrifugation and SDS-polyacrylamide gel electrophoresis were employed. When the purified fusion protein was used for testing its ability to bind to antibodies specific for HCV by enzyme-linked immunosorbent assay, the protein was recognized by antibodies in sera from 90% of HCV-positive patients. Treatment of hGHE2t protein by beta-mercaptoethanol, but not by heat and SDS, significantly reduced its reactivity to the antibodies of patient sera, suggesting that intermolecular and/or intramolecular disulfide bonds are important for its ability to recognize its specific antibody and that the E2 protein contains discontinuous antigenic epitope(s). PMID- 9374480 TI - Interaction of the delta and b subunits contributes to F1 and F0 interaction in the Escherichia coli F1F0-ATPase. AB - Interactions of the F1F0-ATPase subunits between the cytoplasmic domain of the b subunit (residues 26-156, bcyt) and other membrane peripheral subunits including alpha, beta, gamma, delta, epsilon, and putative cytoplasmic domains of the a subunit were analyzed with the yeast two-hybrid system and in vitro reconstitution of ATPase from the purified subunits as well. Only the combination of bcyt fused to the activation domain of the yeast GAL-4, and delta subunit fused to the DNA binding domain resulted in the strong expression of the beta galactosidase reporter gene, suggesting a specific interaction of these subunits. Expression of bcyt fused to glutathione S-transferase (GST) together with the delta subunit in Escherichia coli resulted in the overproduction of these subunits in soluble form, whereas expression of the GST-bcyt fusion alone had no such effect, indicating that GST-bcyt was protected by the co-expressed delta subunit from proteolytic attack in the cell. These results indicated that the membrane peripheral domain of b subunit stably interacted with the delta subunit in the cell. The affinity purified GST-bcyt did not contain significant amounts of delta, suggesting that the interaction of these subunits was relatively weak. Binding of these subunits observed in a direct binding assay significantly supported the capability of binding of the subunits. The ATPase activity was reconstituted from the purified bcyt together with alpha, beta, gamma, delta, and epsilon, or with the same combination except epsilon. Specific elution of the ATPase activity from glutathione affinity column with the addition of glutathione after reconstitution demonstrated that the reconstituted ATPase formed a complex. The result indicated that interaction of b and delta was stabilized by F1 subunits other than epsilon and also suggested that b-delta interaction was important for F1-F0 interaction. PMID- 9374481 TI - Structural and functional roles of modules in hemoglobin. Substitution of module M4 in hemoglobin subunits. AB - The alpha- and beta-subunits of human hemoglobin consist of the modules M1, M2 + M3, and M4, which correspond to the exons 1, 2, and 3, respectively (Go, M. (1981) Nature 291, 90-92). To gain further insight into functional and structural significance of the modules, we designed two kinds of chimeric hemoglobin subunits (chimeric alphaalphabeta- and betabetaalpha-subunits), in which the module M4 was replaced by the partner subunits. CD spectra in the far-UV region showed that the secondary structure of the chimeric alphaalphabeta-subunit drastically collapsed, while the chimeric betabetaalpha-subunit conserved the native globin structure (Wakasugi, K., Ishimori, K., Imai, K., Wada, Y., and Morishima, I. (1994) J. Biol. Chem. 269, 18750-18756). SAXS data also suggested a partially disordered structure of the chimeric alphaalphabeta-subunit. Based on tryptophan fluorescence spectra and computer modeling from x-ray structures of native globins, steric constraint between Trp14 and Tyr125 would be induced in the chimeric alphaalphabeta-subunit, which would perturb the packing of the A- and H-helices and destabilize the globule structure. On the other hand, such a steric constraint was not found for the counterpart chimeric subunit, the betabetaalpha-subunit. The different stabilities of these module-substituted globins imply that modules would not always be stable "structural" units, and interactions between modules are crucial to construct stable globin subunits. PMID- 9374482 TI - The Saccharomyces cerevisiae ACR3 gene encodes a putative membrane protein involved in arsenite transport. AB - The cluster of three genes, ACR1, ACR2, and ACR3, previously was shown to confer arsenical resistance in Saccharomyces cerevisiae. The overexpression of ACR3 induced high level arsenite resistance. The presence of ACR3 together with ACR2 on a multicopy plasmid was conducive to increased arsenate resistance. The function of ACR3 gene has now been investigated. Amino acid sequence analysis of Acr3p showed that this hypothetical protein has hydrophobic character with 10 putative transmembrane spans and is probably located in yeast plasma membrane. We constructed the acr3 null mutation. The resulting disruptants were 5-fold more sensitive to arsenate and arsenite than wild-type cells. The acr3 disruptants showed wild-type sensitivity to antimony, tellurite, cadmium, and phenylarsine oxide. The mechanism of arsenical resistance was assayed by transport experiments using radioactive arsenite. We did not observe any significant differences in the accumulation of 76AsO33- in wild-type cells, acr1 and acr3 disruptants. However, the high dosage of ACR3 gene resulted in loss of arsenite uptake. These results suggest that arsenite resistance in yeast is mediated by an arsenite transporter (Acr3p). PMID- 9374483 TI - Oxidation of free fatty acids in low density lipoprotein by 15-lipoxygenase stimulates nonenzymic, alpha-tocopherol-mediated peroxidation of cholesteryl esters. AB - 15-Lipoxygenase has been implicated in the in vivo oxidation of low density lipoprotein (LDL) a process thought to be important in the origin and/or progression of human atherogenesis. We have suggested previously that oxidation of LDL's cholesteryl esters (CE) and phospholipids by soybean (SLO) or human recombinant 15-lipoxygenase (rhLO) can be ascribed largely to alpha-tocopherol (alpha-TOH)-mediated peroxidation (TMP). In this study we demonstrate that addition to LDL of unesterified linoleate (18:2), other free fatty acid (FFA) substrates, or phospholipase A2 (PLA2) significantly enhanced the accumulation of CE hydro(pero)xides (CE-O(O)H) induced by rhLO, whereas the corresponding CE and nonsubstrate FFA were without effect. The enhanced CE-O(O)H accumulation showed a dependence on the concentration of free 18:2 in LDL. In contrast, addition of 18:2 had little effect on LDL oxidation induced by aqueous peroxyl radicals or Cu2+ ions. Analyses of the regio- and stereoisomers of oxidized 18:2 in SLO treated native LDL demonstrated that the small amounts of 18:2 associated with the lipoprotein were oxidized enzymically and within minutes, whereas cholesteryl linoleate (Ch18:2) was oxidized nonenzymically and continuously over hours. alpha Tocopheroxyl radical (alpha-TO.) formed in LDL exposed to SLO was enhanced by addition of 18:2 or PLA2. With rhLO and 18:2-supplemented LDL, oxidation of 18:2 was entirely enzymic, whereas that of Ch18:2 was largely, though not completely, nonenzymic. The small extent of enzymic Ch18:2 oxidation increased with increasing enzyme to LDL ratios. Ascorbate and the reduced form of coenzyme Q, ubiquinol-10, which are both capable of reducing alpha-TO. and thereby preventing TMP, inhibited nonenzymic Ch18:2 oxidation induced by rhLO. Trolox and ascorbyl palmitate, which also inhibit TMP, ameliorated both enzymic and nonenzymic oxidation of LDL's lipids, whereas probucol, a radical scavenger not capable of preventing TMP, was ineffective. These results demonstrate that rhLO-induced oxidation of CE is largely nonenzymic and increases with LDL's content of FFA substrates. We propose that conditions which increase LDL's FFA content, such as the presence of lipases, increase 15-LO-induced LDL lipid peroxidation and that this process requires only an initial, transient enzymic activity. PMID- 9374484 TI - Protein kinase C-zeta as a downstream effector of phosphatidylinositol 3-kinase during insulin stimulation in rat adipocytes. Potential role in glucose transport. AB - Insulin provoked rapid increases in enzyme activity of immunoprecipitable protein kinase C-zeta (PKC-zeta) in rat adipocytes. Concomitantly, insulin provoked increases in 32P labeling of PKC-zeta both in intact adipocytes and during in vitro assay of immunoprecipitated PKC-zeta; the latter probably reflected autophosphorylation, as it was inhibited by the PKC-zeta pseudosubstrate. Insulin induced activation of immunoprecipitable PKC-zeta was inhibited by LY294002 and wortmannin; this suggested dependence upon phosphatidylinositol (PI) 3-kinase. Accordingly, activation of PI 3-kinase by a pYXXM-containing peptide in vitro resulted in a wortmannin-inhibitable increase in immunoprecipitable PKC-zeta enzyme activity. Also, PI-3,4-(PO4)2, PI-3,4,5-(PO4)3, and PI-4,5-(PO4)2 directly stimulated enzyme activity and autophosphoralytion in control PKC-zeta immunoprecipitates to levels observed in insulin-treated PKC-zeta immunoprecipitates. In studies of glucose transport, inhibition of immunoprecipitated PKC-zeta enzyme activity in vitro by both the PKC-zeta pseudosubstrate and RO 31-8220 correlated well with inhibition of insulin stimulated glucose transport in intact adipocytes. Also, in adipocytes transiently expressing hemagglutinin antigen-tagged GLUT4, co-transfection of wild-type or constitutive PKC-zeta stimulated hemagglutinin antigen-GLUT4 translocation, whereas dominant-negative PKC-zeta partially inhibited it. Our findings suggest that insulin activates PKC-zeta through PI 3-kinase, and PKC zeta may act as a downstream effector of PI 3-kinase and contribute to the activation of GLUT4 translocation. PMID- 9374485 TI - Human recombinant alpha1(V) collagen chain. Homotrimeric assembly and subsequent processing. AB - Human embryonic kidney cells (293-EBNA) have been transfected with the full length human alpha1 chain of collagen V using an episomal vector. High yields (15 microgram/ml) of recombinant collagen were secreted in the culture medium. In presence of ascorbate, the alpha1(V) collagen is correctly folded into a stable triple helix as shown by electron microscopy and pepsin resistance. Circular dichroism data confirm the triple-helix conformation and indicate a melting temperature of 37.5 degrees C for the recombinant homotrimer. The major secreted form is a 250-kDa polypeptide (alpha1FL). N-terminal sequencing and collagenase digestion indicate that alpha1FL retains the complete N-propeptide but lacks the C-propeptide. However, alpha1FL might undergo a further N-terminal trimming into a form (alpha1TH) corresponding to the main triple-helix domain plus the major part of the NC2 domain. This processing is different from the one of the heterotrimeric (alpha1(V))2alpha2(V) and could have some physiological relevance. Analysis of cell homogenates indicates the presence of a 280-kDa polypeptide that is disulfide-linked through its C-terminal globular domain. This C-propeptide is rapidly cleaved after secretion in the medium, giving the first evidence of a C terminal processing of recombinant fibrillar collagens. Rotary shadowing observations not only confirm the presence of a globular domain at the N-terminal end of the molecule but reveal the presence of a kink within the triple helix in a region poor in iminoacids. This region could represent a target for proteases. Together with the thermal stability data, these results might explain the low amount of (alpha1(V))3 recovered from tissues. PMID- 9374486 TI - Expression cloning and characterization of ROAT1. The basolateral organic anion transporter in rat kidney. AB - Expression cloning in Xenopus laevis oocytes was used to isolate an organic anion transport protein from rat kidney. A cDNA library was constructed from size fractionated poly(A)+ RNA and screened for probenecid-sensitive transport of p aminohippurate (PAH). A 2, 227-base pair cDNA clone containing a 1,656-base pair open reading frame coding for a peptide 551 amino acids long was isolated and named ROAT1. ROAT1-mediated transport of 50 mu M [3H]PAH was independent of imposed changes in membrane potential. Transport was significantly inhibited at 4 degrees C, or upon incubation with other organic anions, but not by the organic cation tetraethylammonium, by the multidrug resistance ATPase inhibitor cyclosporin A, or by urate. External glutarate and alpha-ketoglutarate (1 mM), both counterions for basolateral PAH exchange, also inhibited transport, suggesting that ROAT1 is functionally similar to the basolateral PAH carrier. Consistent with this conclusion, PAH uptake was trans-stimulated in oocytes preloaded with glutarate, whereas the dicarboxylate methylsuccinate, which is not accepted by the basolateral exchanger, did not trans-stimulate. Finally, ROAT1 mediated PAH transport was saturable, with an estimated Km of 70 mu M. Each of these properties is identical to those previously described for the basolateral alpha-ketoglutarate/PAH exchanger in isolated membrane vesicles or intact renal tubules. PMID- 9374487 TI - Comparison of lactate transport in astroglial cells and monocarboxylate transporter 1 (MCT 1) expressing Xenopus laevis oocytes. Expression of two different monocarboxylate transporters in astroglial cells and neurons. AB - The transport of lactate is an essential part of the concept of metabolic coupling between neurons and glia. Lactate transport in primary cultures of astroglial cells was shown to be mediated by a single saturable transport system with a Km value for lactate of 7.7 mM and a Vmax value of 250 nmol/(min x mg of protein). Transport was inhibited by a variety of monocarboxylates and by compounds known to inhibit monocarboxylate transport in other cell types, such as alpha-cyano-4-hydroxycinnamate and p-chloromercurbenzenesulfonate. Using reverse transcriptase-polymerase chain reaction and Northern blotting, the presence of mRNA coding for the monocarboxylate transporter 1 (MCT1) was demonstrated in primary cultures of astroglial cells. In contrast, neuron-rich primary cultures were found to contain the mRNA coding for the monocarboxylate transporter 2 (MCT2). MCT1 was cloned and expressed in Xenopus laevis oocytes. Comparison of lactate transport in MCT1 expressing oocytes with lactate transport in glial cells revealed that MCT1 can account for all characteristics of lactate transport in glial cells. These data provide further molecular support for the existence of a lactate shuttle between astrocytes and neurons. PMID- 9374488 TI - Nucleotide hydrolysis-dependent conformational changes in p21(ras) as studied using ESR spectroscopy. AB - We have employed ESR spectroscopy using guanine nucleotides that contain a spin label at the 2',3'-position of the ribose to investigate structural changes in the proto-oncogene product p21(ras) that are dependent on nucleotide hydrolysis. The three nucleotide analogs used were 2',3'-(2,2,5, 5-tetramethyl-3-pyrroline-1 oxyl-3-carboxylic acid ester (SL) GTP, SL-GDP, and the non-hydrolyzable analog SL guanylylimidodiphosphate. SL-GTP was hydrolyzed by p21 with rates similar to those for GTP hydrolysis and appears to be an excellent substrate analog. The ESR spectra of SL-GTP and SL-GDP in complex with p21 differ significantly when acquired at 0 degrees C or 5 degrees C indicating different environments (conformations) of the protein-bound radicals depending on the phosphorylation state of the bound nucleotide. We calculated the rate constant for the conformational change as deduced from the changes in the corresponding ESR spectra upon incubation of the p21.SL-GTP complex at 25 degrees C and compared it to the rate constant of hydrolysis of SL-GTP at the same temperature. The rate constant deduced from the ESR method was similar to that determined by a high performance liquid chromatography technique. The data are in agreement with the idea that a conformational change during GTP hydrolysis by p21 occurs simultaneously with the actual hydrolysis step. PMID- 9374489 TI - The effects of heme pocket hydrophobicity on the ligand binding dynamics in myoglobin as studied with leucine 29 mutants. AB - To examine the effects of heme pocket hydrophobicity on the ligand binding in myoglobin, some artificial mutants of human myoglobin have been prepared, in which less hydrophobic amino acid residue (Ala, Gly, Ser) is located at the Leu29 (10th residue of the B helix) position. CO rebinding rates for the mutants were markedly decelerated, while the 1H, and 15N NMR spectra of the mutants show that the structural changes around the heme iron for these mutants are rather small. The kinetic and structural properties of the mutants indicate that the ligand binding rate depends on the hydrophobicity inside the heme cavity for these mutants in addition to the volume of the side chain at the 29-position. On the basis of the IR stretching frequency of liganded CO, invasion of water molecules into the heme pocket in the mutants is suggested, which would be induced by the decrease in the hydrophobicity due to the amino acid substitution. A slight red shift of the position of the Soret peak for the serine mutant L29S also supports the reduced hydrophobicity inside the heme cavity. We can concluded that, together with the kinetic properties of the mutants, the hydrophobicity of the heme pocket is one of the key factors in regulating the ligand binding to the heme iron. PMID- 9374490 TI - Ileal microvillar protein villin is tyrosine-phosphorylated and associates with PLC-gamma1. Role of cytoskeletal rearrangement in the carbachol-induced inhibition of ileal NaCl absorption. AB - In ileal absorptive cells, carbachol inhibits NaCl absorption and its component brush border Na+/H+ exchanger, acting via basolateral membrane receptors. This carbachol effect involves (i) activation of brush border phosphatidylinositol 4,5 bisphosphate-specific phospholipase C (PLC) activity and brush border but not basolateral membrane translocation of PLC-gamma1 (Khurana, S., Kreydiyyeh, S., Aronzon, A., Hoogerwerf, W. A., Rhee, S. G., Donowitz, M., and Cohen, M. E. (1996) Biochem. J. 313, 509-518); and (ii) brush border tyrosine kinase(s) because mucosal but not serosal addition of the tyrosine kinase inhibitor genistein prevents the carbachol-induced inhibition of NaCl absorption and brush border Na+/H+ exchange. In the present work we identify a pool of villin (a brush border actin-binding protein) in the microvillus membrane fraction of rabbit ileum; this pool of villin is tyrosine-phosphorylated and associates with brush border membrane PLC-gamma1. Villin is present both in the Triton X-100-soluble and -insoluble fractions of the brush border. The Triton X-100-soluble pool is approximately 4-fold smaller than the brush border pool of villin that is present in the Triton X-100-insoluble fraction. Only the villin present in the Triton X 100-soluble fraction of ileal villus brush border associates with PLC-gamma1 and is tyrosine-phosphorylated. Carbachol increases the tyrosine phosphorylation of villin rapidly (as early as 30 s) and transiently. Carbachol also increases the amount of tyrosine-phosphorylated villin that associates with PLC-gamma1. These studies demonstrate that carbachol effects on NaCl absorption are accompanied by an increase in brush border PLC-gamma1 association with villin and an increase in tyrosine phosphorylation of villin. To study the role of cytoskeletal rearrangement in carbachol-induced inhibition of NaCl absorption, we used the F actin stabilizing drug jasplakinolide. Jasplakinolide prevents the carbachol inhibition of ileal NaCl absorption. This suggests that F-actin severing is necessary for carbachol to inhibit ileal villus NaCl absorption. Since villin is known to sever actin, these studies suggest a role for villin in the signaling cascade that begins at the basolateral membrane with carbachol binding to its receptor and ends at the apical membrane in inhibition of NaCl absorption. PMID- 9374492 TI - Sanguinarine (pseudochelerythrine) is a potent inhibitor of NF-kappaB activation, IkappaBalpha phosphorylation, and degradation. AB - The nuclear factor NF-kappaB is a pleiotropic transcription factor whose activation results in inflammation, viral replication, and growth modulation. Due to its role in pathogenesis, NF-kappaB is considered a key target for drug development. In the present report we show that sanguinarine (a benzophenanthridine alkaloid), a known anti-inflammatory agent, is a potent inhibitor of NF-kappaB activation. Treatment of human myeloid ML-1a cells with tumor necrosis factor rapidly activated NF-kappaB, this activation was completely suppressed by sanguinarine in a dose- and time-dependent manner. Sanguinarine did not inhibit the binding of NF-kappaB protein to the DNA but rather inhibited the pathway leading to NF-kappaB activation. The reversal of inhibitory effects of sanguinarine by reducing agents suggests a critical sulfhydryl group is involved in NF-kappaB activation. Sanguinarine blocked the tumor necrosis factor-induced phosphorylation and degradation of IkappaBalpha, an inhibitory subunit of NF kappaB, and inhibited translocation of p65 subunit to the nucleus. As sanguinarine also inhibited NF-kappaB activation induced by interleukin-1, phorbol ester, and okadaic acid but not that activated by hydrogen peroxide or ceramide, the pathway leading to NF-kappaB activation is likely different for different inducers. Overall, our results demonstrate that sanguinarine is a potent suppressor of NF-kappaB activation and it acts at a step prior to IkappaBalpha phosphorylation. PMID- 9374491 TI - Characterization of the structure and function of the fourth member of p38 group mitogen-activated protein kinases, p38delta. AB - We have cloned and characterized a new member of the p38 group of mitogen activated protein kinases here termed p38delta. Sequence comparisons revealed that p38delta is approximately 60% identical to the other three p38 isoforms but only 40-45% to the other mitogen-activated protein kinase family members. It contains the TGY dual phosphorylation site present in all p38 group members and is activated by a group of extracellular stimuli including cytokines and environmental stresses that also activate the other three known p38 isoforms. However, unlike the other p38 isoforms, the kinase activity of p38delta is not blocked by the pyridinyl imidazole, 4-(4-fluorophenyl)-2-2(4-hydroxyphenyl)-5-(4 pyridyl)-imidazole (identicalto SB202190). p38delta can be activated by MKK3 and MKK6, known activators of the other isoforms. Nonetheless, in-gel kinase assays provide evidence for additional activators. The data presented herein show that p38delta has many properties that are similar to those of other p38 group members. Nonetheless important differences exist among the four members of the p38 group of enzymes, and thus each may have highly specific, individual contributions to biologic events involving activation of the p38 pathways. PMID- 9374493 TI - The human papillomavirus E7 oncoprotein functionally interacts with the S4 subunit of the 26 S proteasome. AB - Human papillomaviruses (HPV) have been etiologically linked to human cervical cancer. More than 90% of cervical cancer tissues express two HPV-encoded oncoproteins E6 and E7. Both E6 and E7 proteins possess transformation activity. and together they cooperate to transform primary human keratinocytes, fibroblasts. and epithelial cells. The transforming activity of E7 is associated with its ability to bind the retinoblastoma tumor suppressor protein (Rb). However, the carboxyl-terminal mutants of E7 are also defective for transformation, suggesting that other cellular targets for E7 might exist. We screened a human placenta cDNA library by yeast two-hybrid assay using HPV 16 E7 as a bait and identified the subunit 4 (S4) ATPase of the 26 S proteasome as a novel E7-binding protein. E7 binds to S4 through the carboxyl-terminal zinc binding motif, and the binding is independent of E7 sequences involved in binding to Rb. The interaction between S4 and E7 can be easily detected by in vitro protein binding assays. Moreover, we found that E7 increases the ATPase activity of S4. A recent study has shown that, in epithelial cells, E7 degrades Rb through the 26 S proteasome pathway. We hypothesize that E7 might target Rb for degradation by 26 S proteasome through its interaction with the subunit 4 of the proteasome. PMID- 9374494 TI - Identification of an amino acid residue that lies between the exofacial vestibule and exofacial substrate-binding site of the Glut1 sugar permeation pathway. AB - A valine-to-isoleucine mutation at amino acid residue 197 of Glut2 or the equivalent residue 165 of Glut1 has been shown to impair glucose transport activity. This mutation was originally discovered in the Glut2 gene of a patient with type 2 diabetes. We investigated the mechanism of the effect of this mutation on transport activity via the analysis of Glut1 mutants expressed in Xenopus oocytes combined with cysteine substitution mutagenesis and the use of cysteine-reactive chemical probes. Aliphatic side chain substitutions at position 165 that were bulkier than the native valine residue inhibited glucose transport activity, whereas substitutions of less bulky side chains had little effect on transport, suggesting a role for steric hindrance. A cysteine residue was introduced at position 165 of a functional, cysteine-less Glut1 construct, and this mutant was then tested for inhibition of transport activity by a membrane impermeant sulfhydryl-specific reagent (p-chloromercuribenzenesulfonate). p Chloromercuribenzenesulfonate inhibited activity of the Cys165 mutant when it was added to the external buffer but not when it was injected directly into oocytes, indicating that this residue is accessible from the external solvent but not from the cytoplasm. Competition experiments indicated that Cys165 lies near the exofacial substrate-binding site or directly in the sugar permeation pathway. These data provide evidence that the side chain of Val165, which resides in the middle of transmembrane helix 5, juts into the aqueous permeation pathway of Glut1, probably between the exofacial substrate-binding site and the outer vestibule of the pathway. PMID- 9374495 TI - Kinetic mechanism of GTP binding and RNA synthesis during transcription initiation by bacteriophage T7 RNA polymerase. AB - We have used stopped-flow and rapid chemical quench-flow methods to investigate the kinetics of the early steps during transcription initiation by bacteriophage T7 RNA polymerase. Most promoters of T7 RNA polymerase initiate with two GTPs. The kinetics of GTP binding was investigated by monitoring the fluorescence changes resulting from GTP binding to polymerase and fluorescent 2-aminopurine containing promoter DNA complex. Scheme 1 was determined from studies of T7 Phi10 promoter at 25 degrees C, where (E.D)n represents the polymerase.DNA complex in different conformations. GTPE and GTPI represent the elongating and initiating GTP molecules incorporated at the +2 and +1 positions, respectively. Our studies show that GTP at the elongation site binds with at least 10-fold tighter affinity than the GTP at the initiation site. Two conformational changes were revealed upon GTP binding to the polymerase.2-aminopurine DNA complex. The first conformational change occurred upon GTP binding to the elongation site. This conformational change was reversible, and studies with partially melted DNA and incorrect NTPs suggested that it may represent a DNA melting and/or base pairing step. A second rate-limiting conformational change whose rate was same as the maximum rate of pppGpG synthesis occurred after two GTPs were bound. As with DNA polymerases, this rate-limiting conformational change probably occurs at each NMP incorporation event and may be involved in proper positioning of the initiation and the elongating GTPs within the polymerase active site to achieve efficient and accurate RNA synthesis. PMID- 9374496 TI - Lysophosphatidylcholine regulates cationic amino acid transport and metabolism in vascular smooth muscle cells. Role in polyamine biosynthesis. AB - Lysophosphatidylcholine (lyso-PC) is a major component of atherogenic lipids that stimulate vascular smooth muscle cell (SMC) proliferation. Because cationic amino acids are metabolized to growth-stimulatory polyamines, we examined whether lyso PC regulates the transcellular transport and metabolism of cationic amino acids by vascular SMC. Treatment of SMC with lyso-PC initially (0-2 h) decreased cationic amino acid uptake, whereas longer exposures (6-24 h) progressively increased transport. Kinetic studies indicated that lyso-PC-induced inhibition was associated with a decrease in affinity for cationic amino acids, but the stimulation was mediated by an increase in transport capacity. Lyso-PC strongly induced the expression of cationic amino acid transporter-2 mRNA while modestly elevating the level of cationic amino acid transporter-1 mRNA. In addition, lyso PC stimulated intracellular cationic amino acid metabolism by inducing ornithine decarboxylase activity and mRNA expression and also by inducing arginase activity in vascular SMC. In contrast, lyso-PC inhibited the catabolism of L-arginine to nitric oxide by blocking inducible nitric oxide synthase expression. Lyso-PC increased markedly the capacity of SMC to generate putrescine, a polyamine, from extracellular L-ornithine and L-arginine. The lyso-PC-mediated increase in the production of putrescine was reversed by NG-methyl-L-arginine, a competitive inhibitor of cationic amino acid transport, or by alpha-difluoromethylornithine, an ornithine decarboxylase inhibitor. The formation of putrescine from L-arginine was also prevented by arginase inhibitor NG-hydroxy-L-arginine. These results demonstrate that lyso-PC stimulates polyamine synthesis in vascular SMC by inducing the expression of the genes that regulate both the transport and metabolism of cationic amino acids. The actions of lyso-PC in stimulating cationic amino acid uptake and directing their metabolism to growth-stimulatory polyamines while simultaneously inhibiting the synthesis of antiproliferative NO, may contribute to lyso-PC-induced SMC proliferation and atherosclerotic lesion formation. PMID- 9374497 TI - Tissue factor positions and maintains the factor VIIa active site far above the membrane surface even in the absence of the factor VIIa Gla domain. A fluorescence resonance energy transfer study. AB - Coagulation factor VIIa (fVIIa), a soluble serine protease, exhibits full proteolytic activity only when bound to its cofactor, tissue factor (TF). Both proteins interact with membranes; TF is an integral membrane protein, while fVIIa binds reversibly to phospholipid surfaces via its Gla domain. In this study, we examine the extent to which the location of the fVIIa active site in the fVIIa.TF complex is determined by the fVIIa Gla domain. A fluorescein dye was covalently attached to the active site of fVIIa lacking the Gla domain (Gla domainless fVIIa, GD-fVIIa) via a tripeptide tether to yield fluorescein-D-Phe-Pro-Arg-GD fVIIa (Fl-FPR-GD-fVIIa). The location of the active site of GD-fVIIa relative to the membrane surface was determined using fluorescence resonance energy transfer between the fluorescein dye in the active site of GD-fVIIa and octadecylrhodamine (OR) at the surface of phospholipid vesicles. As expected, no energy transfer was observed between Fl-FPR-GD-fVIIa and OR in vesicles composed of phosphatidylcholine/phosphatidylserine (PC/PS, 4:1) because the Gla domain is required for the binding of fVIIa to phospholipid. However, when Fl-FPR-GD-fVIIa was titrated with PC or PC/PS vesicles into which purified TF had been reconstituted, energy transfer was observed. Based on the dependence of fluorescence resonance energy transfer on OR density, the average distance of closest approach between fluorescein in the active site of Fl-FPR-GD-fVIIa.TF and OR at the vesicle surface was determined to be 78 A (kappa2 = (2)/(3)). Since this value is nearly the same as that obtained with intact Fl-FPR-fVIIa bound to TF, the presence or absence of the fVIIa Gla domain has only a small effect on the location of the active site in the fVIIa.TF complex. The extracellular domain of tissue factor therefore must be fairly rigid and fixed relative to the surface to position and maintain the fVIIa active site far above the membrane even in the absence of the fVIIa Gla domain. PMID- 9374499 TI - Importance of a novel oxidative mechanism for elimination of brain cholesterol. Turnover of cholesterol and 24(S)-hydroxycholesterol in rat brain as measured with 18O2 techniques in vivo and in vitro. AB - The brain is the most cholesterol-rich organ in the body. Brain cholesterol is characterized by a very low turnover with very little exchange with lipoproteins in the circulation. Very recently we showed that there is a continuous age dependent flux of 24(S)-hydroxycholesterol from the human brain into the circulation (Lutjohann, D., Breuer, O., Ahlborg, G., Nennesmo, I., Siden, A., Diczfalusy, U., and Bjorkhem, I. (1996) Proc. Natl. Acad. Sci. U. S. A. 93, 9799 9804). Here we measured the rate of synthesis of cholesterol as well as the conversion of cholesterol into 24(S)-hydroxycholesterol in rat brain in vivo with use of an 18O2 inhalation technique and mass isotopomer distribution analysis. Cholesterol synthesis was found to correspond to 0.03 +/- 0.01% of the pool per h. Conversion of cholesterol into 24(S)-hydroxycholesterol was of a similar magnitude, about 0.02% of the pool per h. Brain microsomes converted endogenous cholesterol into 24(S)-hydroxycholesterol at a similar rate when incubated in the presence of NADPH. When incubated with whole homogenate and subcellular fractions of rat brain, there was no significant conversion of tritium-labeled 24 hydroxycholesterol into more polar products. Plasma from 18O2-exposed rats contained 24(S)-hydroxycholesterol with an enrichment of 18O similar to that in 24(S)-hydroxycholesterol in the brain. The results suggest that the present 24(S) hydroxylase mediated mechanism is most important for elimination of cholesterol from the brain of rats. There is a slow conversion of brain cholesterol into 24(S)-hydroxycholesterol with a rapid turnover of the small pool of the latter oxysterol due to leakage to the circulation (half-life of brain 24(S) hydroxycholesterol is about 0.5 days as compared with 2-4 months for brain cholesterol). It is evident that the 24(S)-hydroxylation greatly facilitates transfer of cholesterol over the blood-brain barrier and that this hydroxylation may be critical for cholesterol homeostasis in the brain. PMID- 9374498 TI - Tumor necrosis factor-alpha increases ATP content in metabolically inhibited L929 cells preceding cell death. AB - The effects of tumor necrosis factor-alpha (TNF) on ATP levels were studied in metabolically inhibited L929 cells. Treatment of these cells with TNF in the presence of actinomycin D or cycloheximide induces cyclic changes in the intracellular ATP content preceding cell death. After 3 h of incubation, the intracellular ATP content increased by 48 +/- 6% (p < 0.001), but at 4 h, it decreased to the control level. Two hours later, it increased again by 23 +/- 5% over the control level (p < 0.001). Coinciding with cell death, ATP content decreased progressively until almost complete depletion. These changes in ATP content were associated with parallel alterations in the respiratory coupling and with increased generation of reactive oxygen species. The mechanism by which TNF/actinomycin D or TNF/cycloheximide increased cellular ATP seemed to be dependent on the mitochondrial ATP synthesis and related to the cytotoxic effect of TNF, since blockade of mitochondrial electron transport prevented the increase in cellular ATP, the formation of reactive oxygen species, and the apoptotic cell death caused by TNF. We suggest that the TNF/actinomycin D- or TNF/cycloheximide induced changes in intracellular ATP levels may be involved in the cytotoxic effect of TNF in metabolically inhibited L929 cells. PMID- 9374500 TI - Overexpression of cellular Src in fibroblasts enhances endocytic internalization of epidermal growth factor receptor. AB - Previous studies have demonstrated a requirement for the nonreceptor tyrosine kinase, cellular Src (c-Src), in epidermal growth factor (EGF)-induced mitogenesis and a synergistic interaction between c-Src and EGF receptor (EGFR) in tumorigenesis. Although endocytic internalization of EGFR may be thought to attenuate EGF-stimulated signaling, recent evidence suggests that signaling through Ras can be amplified by repeated encounters of endosome-localized, receptor. Shc.Grb2.Sos complexes with the plasma membrane, where Ras resides almost exclusively. Based on these reports, we examined EGFR trafficking behavior in a set of single and double c-Src/EGFR C3H10T1/2 overexpressors to determine if c-Src affects basal receptor half-life, ligand-induced internalization, and/or recycling. Our results show that overexpression of c-Src causes no change in EGFR half-life but does produce an increase in the internalization rate constant of EGF.EGFR complexes when the endocytic apparatus is not stoichiometrically saturated; this effect of c-Src on EGFR endocytosis is negligible at high receptor occupancy in cells overexpressing the receptor. In neither case are EGFR recycling rate constants affected by c-Src. These data indicate a functional role for c-Src in receptor internalization, which in turn could alter some aspects of EGFR signaling related to mitogenesis and tumorigenesis. PMID- 9374501 TI - Analysis of the human factor VIII A2 inhibitor epitope by alanine scanning mutagenesis. AB - Antibodies directed to the A2 domain of factor VIII (fVIII) are usually an important component of the polyclonal response in patients who have clinically significant inhibitory antibodies to fVIII. A major determinant of the A2 epitope has been located by homolog scanning mutagenesis using recombinant hybrid human/porcine fVIII molecules to a sequence bounded by Arg484-Ile508 (Healey, J. F. , Lubin, I. M., Nakai, H., Saenko, E. L., Hoyer, L. W., Scandella, D. , and Lollar, P. (1995) J. Biol. Chem. 270, 14505-14509). Within this region, human residues Arg484, Pro485, Tyr487, Ser488, Arg489, Pro492, Val495, Phe501, and Ile508 differ from porcine fVIII. We stably expressed in mammalian cells nine active B-domainless human fVIII molecules containing single alanine substitutions at these sites. Their inhibition by a murine anti-A2 monoclonal antibody, monoclonal antibody (mAb) 413, and by three A2-specific alloimmune and two A2 specific autoimmune human inhibitor plasmas was measured by the Bethesda assay. The inhibition of Arg484 --> Ala, Tyr487 --> Ala, Arg489 --> Ala, and Arg492 --> Ala by mAb413 was reduced by greater than 90% compared with wild-type, B domainless human fVIII. mAb413 inhibited the most severely affected mutant, Arg489 --> Ala, 0.01% as well as wild-type fVIII. For all five patient plasmas, the Tyr487 --> Ala mutant displayed the greatest reduction in inhibition. The inhibition of the Tyr487 --> Ala mutant by these antibodies ranged from 10% to 20% that of wild-type fVIII. The inhibition of the Ser488 --> Ala, Arg489 --> Ala, Pro492 --> Ala, Val495 --> Ala, Phe501 --> Ala, and Ile508 --> Ala mutants by most of the plasmas also was significantly reduced. In contrast, the Arg484 - > Ala and Pro485 --> Ala mutants were relatively unaffected. Thus, although mAb413 binds to the same region as human A2 inhibitors, it recognizes a different set of amino acid side chains. The side chains recognized by human A2 inhibitors appear to be similar, despite the differing immune settings that give rise to fVIII alloantibodies and autoantibodies. PMID- 9374502 TI - Sphingolipids are potential heat stress signals in Saccharomyces. AB - The ability of organisms to quickly respond to stresses requires the activation of many intracellular signal transduction pathways. The sphingolipid intermediate ceramide is thought to be particularly important for activating and coordinating signaling pathways during mammalian stress responses. Here we present the first evidence that ceramide and other sphingolipid intermediates are signaling molecules in the Saccharomyces cerevisiae heat stress response. Our data show a 2 3-fold transient increase in the concentration of C18-dihydrosphingosine and C18 phytosphingosine, more than a 100-fold transient increase in C20 dihydrosphingosine and C20-phytosphingosine, and a more stable 2-fold increase in ceramide containing C18-phytosphingosine and a 5-fold increase in ceramide containing C20-phytosphingosine following heat stress. Treatment of cells with dihydrosphingosine activates transcription of the TPS2 gene encoding a subunit of trehalose synthase and causes trehalose, a known thermoprotectant, to accumulate. Dihydrosphingosine induces expression of a STRE-LacZ reporter gene, showing that the global stress response element, STRE, found in many yeast promoter sequences can be activated by sphingolipid signals. The TPS2 promoter contains four STREs that may mediate dihydrosphingosine responsiveness. Using genetic and other approaches it should be possible to identify sphingolipid signaling pathways in S. cerevisiae and quantify the importance of each during heat stress. PMID- 9374503 TI - Binding of retinol in both retinoid-binding sites of interphotoreceptor retinoid binding protein (IRBP) is stabilized mainly by hydrophobic interactions. AB - Interphotoreceptor retinoid-binding protein (IRBP) is an ocular protein which is believed to participate in the visual cycle by mediating transport of retinoids between pigment epithelium and photoreceptor cells. The molecular mechanism underlying the ability of IRBP to target particular retinoids to the specific cells that are their sites of action and metabolism is not completely clear, and little information is available regarding the structure of the protein's multiple ligand-binding sites. IRBP possesses two retinoid-binding sites, and it was reported that binding of the visual chromophore, 11-cis-retinal, in one of these sites, but not in the other, is tightly regulated by another IRBP ligand, docosahexaenoic acid (Chen, Y., Houghton, L. A., Brenna, J. T., and Noy, N. (1996) J. Biol. Chem. 271, 20507). The two sites are thus functionally distinct. Here, the thermodynamic parameters governing the interactions of retinol with the IRBP retinoid-binding sites were measured. The data demonstrate that the interactions of retinol with both sites are stabilized mainly by hydrophobic interactions, and that the hydroxyl head group of retinol is not involved in formation of protein-ligand complexes. Nevertheless, the data indicate that the two sites are structurally distinct, and that binding of retinol in them occurs by remarkably different modes of interactions. PMID- 9374505 TI - No evidence for involvement of mouse protein-tyrosine phosphatase-BAS-like Fas associated phosphatase-1 in Fas-mediated apoptosis. AB - Recently, one of the PDZ domains in the cytosolic protein-tyrosine phosphatase Fas-associated phosphatase-1 (FAP-1)/protein-tyrosine phosphatase-BAS (PTP-BAS) was shown to interact with the carboxyl-terminal tS-L-V peptide of the human Fas receptor (Sato, T., Irie, S., Kitada, S., and Reed, J. C. (1995) Science 268, 411 415), suggesting a role for protein (de)phosphorylation in Fas signaling. To investigate whether this interaction is conserved in mouse, we performed yeast two-hybrid interaction experiments and transfection studies in mouse T cell lines. For the corresponding PDZ motif in the mouse homologue of FAP-1/PTP-BAS, protein-tyrosine phosphatase-BAS-like (PTP-BL), only an interaction with human but not with mouse Fas could be detected. Presence of the tS-L-V motif proper, which is unique for human Fas, rather than the structural context of its carboxyl terminus, apparently explains the initially observed binding. To test for functional conservation of any indirect involvement of PTP-BL in Fas-mediated signaling, we generated T lymphoma cell lines stably expressing mouse or human Fas receptor with and without PTP-BL. No inhibitory effect of PTP-BL was observed upon triggering apoptosis using mouse or human Fas-activating antibodies. Together with the markedly different tissue expression patterns for PTP-BL and Fas receptor, our findings suggest that protein-tyrosine phosphatase PTP-BL does not play a key role in the Fas-mediated death pathway. PMID- 9374504 TI - Two naturally occurring insulin receptor tyrosine kinase domain mutants provide evidence that phosphoinositide 3-kinase activation alone is not sufficient for the mediation of insulin's metabolic and mitogenic effects. AB - We have recently reported (1) that two naturally occurring mutants of the insulin receptor tyrosine kinase domain, Arg-1174 --> Gln and Pro-1178 --> Leu (Gln-1174 and Leu1178, respectively), both found in patients with inherited severe insulin resistance, markedly impaired receptor tyrosine autophosphorylation, with both mutant receptors being unable to mediate the stimulation of glycogen synthesis or mitogenesis by insulin when expressed in Chinese hamster ovary cells. However, these mutations did not fully prevent IRS-1 phosphorylation in response to insulin in these cells, suggesting that IRS-1 alone may not be sufficient to mediate insulin's metabolic and mitogenic effects. In the present study, we have demonstrated that these mutations also impair the ability of the insulin receptor to activate the transcription factor Elk-1 and promote GLUT4 translocation to the plasma membrane. Although at low concentrations of insulin, the mutant receptors were impaired in their ability to stimulate the tyrosine phosphorylation of IRS 1, at higher insulin concentrations we confirmed that the cells expressing the mutant receptors showed significantly increased tyrosine phosphorylation of IRS-1 compared with parental nontransfected cells. In addition, at comparable insulin concentrations, the association of the p85alpha subunit of phosphoinositide 3 kinase (PI3-kinase) with IRS-1 and the enzymatic activity of IRS-1-associated PI3 kinase were significantly enhanced in cells expressing the mutant receptors. In contrast, no significant stimulation of the tyrosine phosphorylation of Shc, GTP loading of Ras, or mitogen-activated protein kinase phosphorylation was seen in cell lines expressing these mutant receptors. Thus, no activation of any measurable mitogenic or metabolic response was detectable, despite significant insulin-induced phosphorylation of IRS-1 and its association with PI3-kinase in cells stably expressing the mutant insulin receptors. These findings suggest that PI3-kinase activation alone may be insufficient to mediate a wide range of the metabolic and mitogenic effects of insulin. Additionally, the data provide support for the notion that insulin activation of Ras is more closely linked with Shc, and not IRS-1, phosphorylation. PMID- 9374507 TI - The RepA protein of plasmid RSF1010 is a replicative DNA helicase. AB - The RepA protein of the mobilizable broad host range plasmid RSF1010 has a key function in its replication. RepA is one of the smallest known helicases. The protein forms a homohexamer of 29,896-Da subunits. A variety of methods were used to analyze the quaternary structure of RepA. Gel filtration and cross-linking experiments demonstrated the hexameric structure, which was confirmed by electron microscopy and image reconstruction. These results agree with recent data obtained from RepA crystals diffracting at 3.5-A resolution (Roleke, D., Hoier, H., Bartsch, C., Umbach, P., Scherzinger, E., Lurz, R., and Saenger, W. (1997) Acta Crystallogr. Sec. D 53, 213-216). The RepA helicase has 5' --> 3' polarity. As do most true replicative helicases, RepA prefers a tailed substrate with an unpaired 3'-tail mimicking a replication fork. Optimal unwinding activity was achieved at the remarkably low pH of 5.5. In the presence of Mg2+ (Mn2+) ions, the RepA activity is fueled by ATP, dATP, GTP, and dGTP and less efficiently by CTP and dCTP. UTP and dTTP are poor effectors. Nonhydrolyzable ATP analogues, ADP, and pyrophosphate inhibit the helicase activity, whereas inorganic phosphate does not. The presence of Escherichia coli single-stranded DNA-binding protein stimulates unwinding at physiological pH 2-3-fold, whereas the RSF1010 replicon specific primase, RepB' protein, has no effect, either in the presence or in the absence of single-stranded DNA-binding protein. PMID- 9374506 TI - Receptor-associated protein in an oviparous species is correlated with the expression of a receptor variant. AB - The biosynthesis of proteins containing cysteine-rich domains requires chaperones for their correct folding. For instance, the 39-kDa receptor-associated protein (RAP) aides in the cell-surface targeting of newly synthesized members of the mammalian low density lipoprotein receptor (LDLR) gene family, which contains tandemly arranged clusters of hexacysteine repeats. In the chicken, an LDLR relative with eight such repeats is expressed as two different splice variant forms in cell type-specific fashion (Bujo, H., Lindstedt, K. A., Hermann, M., Mola Dalmau, L., Nimpf, J., and Schneider, W. J. (1995) J. Biol. Chem. 270, 23546 23551). To learn more about evolutionary aspects of RAP, its role in escorting of these different receptor splice variants, and other potential functions, we have extended our studies on the avian LDLR family to RAP. cDNA cloning, determination of tissue expression at both the transcript and the protein level, stable expression in COS cells, and binding studies with chicken RAP revealed that mammalian RAPs have retained many features of the non-amniotic proteins. However, structural details, e.g. the well defined internal triplicate repeats in the chicken protein, have been somewhat diluted during evolution. Interestingly, chicken RAP was found to correlate positively with the expression levels in somatic cells of the larger splice variant of the eight-cysteine repeat receptor, but not with those of the smaller variant, expressed only in germ cells. This is compatible with the possibility that RAP may play a role in receptor biology that could be complementing its function in assisting folding. Chicken RAP in crude extracts of the stable expressor COS cells is able to bind to LDLR relatives in ligand blots without requirement for prior purification of the ligand. Thus, in conjunction with the avian model of massive lipid transport to germ cells, these cells provide a novel comparative system amenable to investigation of the biological functions of RAP. PMID- 9374508 TI - Cytokine receptor-independent, constitutively active variants of STAT5. AB - STAT (signal transducers and activators of transcription) proteins are dual function proteins, which participate in cytokine-mediated signal transduction events at the cell surface and transcriptional regulation in the nucleus. We have exploited insights into the activation mechanism of STAT factors to derive constitutively active variants. Chimeric genes encoding fusion proteins of STAT5 and the kinase domain of JAK2 have been derived. The functional properties of the fusion proteins have been investigated in transiently transfected COS cells or in HeLa cells stably transfected with STAT5-JAK2 gene constructs regulated by a tetracycline-sensitive promoter. The STAT5-JAK2 proteins exhibit tyrosine kinase activity and are phosphorylated on tyrosine. The molecules are activated through an intramolecular or a cross-phosphorylation reaction and exhibit constitutive, STAT5-specific DNA binding activity. The transactivation potentials of three constitutively activated STAT5-JAK2 variants comprising different transactivation domains (TADs) derived from STAT5, STAT6, and VP16 were compared. The chimeric molecule containing the STAT5 TAD had no or only a very low, the molecule with the STAT6 TAD a medium, and the molecule with the VP16 TAD a very high transactivation potential. Transcription from STAT5-responsive gene promoter regions of the beta-casein, oncostatin M, and the cytokine-inducible Src homology 2 domain-containing protein genes was observed. These chimeric STAT molecules allow the study of the function of STAT5 independent of cytokine receptors and the activation of other signal transduction pathways. PMID- 9374509 TI - Mutation Lys758 --> Ile of the sarcoplasmic reticulum Ca2+-ATPase enhances dephosphorylation of E2P and inhibits the E2 to E1Ca2 transition. AB - The highly conserved lysine residue Lys758 in the fifth stalk segment of the sarcoplasmic reticulum Ca2+-ATPase was substituted with either isoleucine or arginine by site-directed mutagenesis. The substitution with arginine was without significant effects on Ca2+-ATPase function, whereas multiple changes of functional characteristics were observed with the Lys758 --> Ile mutant. These included insensitivity of ATPase activity to the calcium ionophore A23187, an alkaline shift of the pH dependence of ATPase activity, reduced maximum molecular turnover rate and steady-state phosphorylation level, reduced apparent affinities for Ca2+ and inorganic phosphate, as well as increased sensitivity to inhibition by vanadate. Analysis of the partial reaction steps of the enzyme cycle traced these changes to two steps. The rate of dephosphorylation of the ADP-insensitive phosphoenzyme intermediate (E2P) was increased, irrespective of variations of pH, K+, Ca2+, and dimethyl sulfoxide concentration. In addition, the rate of conversion of the dephosphoenzyme with low Ca2+ affinity (E2) to the Ca2+-bound form activated for phosphorylation (E1Ca2) was reduced in the mutant, and the ATP induced rate enhancement of this step required higher ATP concentrations in the mutant compared with the wild type. PMID- 9374510 TI - Specificity of substrate recognition by Pseudomonas fluorescens N3 dioxygenase. The role of the oxidation potential and molecular geometry. AB - Pseudomonas fluorescens N3 is able to grow on naphthalene as the sole carbon and energy source. The mutant TTC1, blocked at the dihydrodiol dehydrogenase level, which can transform the hydrocarbon into the corresponding dihydrodiol, has been used to produce bioconversion products. To rationalize the different grades of conversion obtained with different substrates, a study was performed using non naphthalene derivatives, including benzenes, conjugated benzenes, and polycyclic aromatic hydrocarbons. The corresponding diols obtained by bioconversion have been isolated and characterized. A theoretical model that considers both energy and geometry factors has been proposed to rationalize the experimental data. Good agreement has been found between the calculated values and the experimental results. PMID- 9374511 TI - Fatty acids decrease IDX-1 expression in rat pancreatic islets and reduce GLUT2, glucokinase, insulin, and somatostatin levels. AB - IDX-1 (islet/duodenum homeobox-1) is a transcription factor expressed in the duodenum and pancreatic beta and delta cells. It is required for embryonic development of the pancreas and transactivates the Glut2, glucokinase, insulin, and somatostatin genes. Here we show that exposure of isolated rat pancreatic islets to palmitic acid induced a approximately 70% decrease in IDX-1 mRNA and protein expression as well as 40 and 65% decreases in the binding activity of IDX 1 for its cognate cis-regulatory elements of the Glut2 and insulin promoters, respectively. The inhibitory effect of palmitic acid required its mitochondrial oxidation since it was prevented by the carnitine palmitoyltransferase I inhibitor bromopalmitic acid. The palmitic acid effect on IDX-1 was correlated with decreases in GLUT2 and glucokinase expression of 40 and 25%, respectively, at both the mRNA and protein levels. Insulin and somatostatin mRNA expression was also decreased by 40 and 60%, whereas glucagon mRNA expression was not modified. After 48 h of exposure to fatty acids, total islet insulin, somatostatin, and glucagon contents were decreased by 85, 55, and 65%, respectively. At the same time, total hormone release was strongly stimulated (13-fold) for glucagon, whereas its was only marginally increased for insulin and somatostatin (1.5- and 1.7-fold, respectively). These results indicate that elevated fatty acid levels 1) negatively regulate Idx-1 expression; 2) decrease the expression of genes transactivated by IDX-1 such as those for GLUT2, glucokinase, insulin, and somatostatin; and 3) lead to an important increase in glucagon synthesis and secretion. Fatty acids thus have pleiotropic effects on pancreatic islet gene expression, and the negative control of Idx-1 expression may be an initial event in the development of these multiple defects. PMID- 9374512 TI - Estrogen does not inhibit 2,3,7, 8-tetrachlorodibenzo-p-dioxin-mediated effects in MCF-7 and Hepa 1c1c7 cells. AB - The estrogen receptor and aryl hydrocarbon receptor (AhR) are coexpressed in several Ah and estrogen-responsive human breast cancer cell lines. However, a recent study reported that 17beta-estradiol (E2) inhibited Ah responsiveness in mouse Hepa 1c1c7 hepatoma cells (Kharat, I., and Saatcioglu, F. (1996) J. Biol. Chem. 271, 10533-10537), and therefore, estrogen receptor-AhR cross-talk was reinvestigated in MCF-7 and mouse Hepa 1c1c7 cells. Treatment of MCF-7 or Hepa 1c1c7 cells with 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) resulted in induction of CYP1A1-dependent activity and mRNA levels. Treatment of both cell lines with E2 had no effect on basal or TCDD-inducible CYP1A1-dependent activity or mRNA levels. In MCF-7 and Hepa 1c1c7 cells transiently transfected with an Ah responsive plasmid containing the 5'-regulatory region of the human CYP1A1 gene fused to the chloramphenicol acetyltransferase reporter gene 10 nM TCDD significantly induced chloramphenicol acetyltransferase activity; in cells cotreated with TCDD plus E2 the induced response was not affected by the hormone. Nuclear extracts from cells treated with dimethyl sulfoxide, E2, TCDD, and TCDD plus E2 were incubated with the [32P]dioxin-responsive element and analyzed by gel electrophoretic mobility shift assays. A retarded band associated with formation of a [32P]dioxin-responsive element-AhR complex was observed in nuclear extracts from cells treated with TCDD or TCDD plus E2 (cotreated). Collectively these studies suggest that E2 does not modulate AhR-mediated CYP1A1 gene expression in MCF-7 or Hepa 1c1c7 cells. PMID- 9374513 TI - Kinetic pathway for the slow to fast transition of thrombin. Evidence of linked ligand binding at structurally distinct domains. AB - The kinetic pathway for the Na+-induced slow --> fast transition of thrombin was characterized. The slow form was shown to consist of two conformers in a 3:1 ratio (ES2:ES1) at 5 degrees C, pH 7.4, Gamma/2 0.3. ES2 binds Na+ 3 orders of magnitude faster than does ES1. The small molecule active site-directed inhibitor L-371,912, and the exosite I binding ligand hirugen, like Na+, bind selectively to ES2 and induce the slow --> fast conversion of thrombin. The slow --> fast transition is limited by the rate of conversion of ES1 to ES2 (k approximately 28 s-1 at 5 degrees C). Replacement of Arg-221a or Lys-224 at the Na+ binding site with Ala appears to selectively alter the slow form and reduce the apparent affinity of the mutants for Na+ and L-371,912. This replacement, however, has little effect on the affinity for the inhibitor in the presence of saturating concentrations of Na+. The kinetically linked ligand binding at the Na+ binding site, exosite I, and the active site of thrombin characterized in the present study indicates the basis for the plasticity of this important enzyme, and suggests the possibility that the substrate specificity and, therefore, the procoagulant and anticoagulant activities of thrombin may be subject to allosteric regulation by as yet unidentified physiologically important effectors. PMID- 9374514 TI - The N-terminal structure of HIV-1 Tat is required for suppression of CD26 dependent T cell growth. AB - Evidence exists that the human immunodeficiency virus-1 (HIV-1) transactivator Tat occurs extracellularly and is involved in the immunosuppression of non-HIV-1 infected T cells of acquired immunodeficiency syndrome (AIDS) patients. The mechanism of this immunosuppressive activity of Tat has been controversially discussed. Interestingly, Tat binds to the T cell activation marker CD26, which has been shown to play a key role in the regulation of growth of lymphocytes and to inhibit its dipeptidyl peptidase IV (DP IV) activity. Here we show that the N terminal nonapeptide MDPVDPNIE of Tat is a competitive inhibitor of DP IV and suppresses DNA synthesis of tetanus toxoid-stimulated peripheral blood mononuclear cells. Amino acid exchanges at positions 5 and 6 strongly weaken these effects. 1H nuclear magnetic resonance and molecular dynamics simulations of Tat(1-9), I5-Tat(1-9), and L6-Tat(1-9) suggest a similar backbone conformation for Tat(1-9) and L6-Tat(1-9). The solution conformation of I5-Tat(1-9) considerably differs from the other two. However, Tat(1-9) fits into our previously proposed active site model of DP IV in contrast to I5-Tat(1-9) and L6 Tat(1-9). Conformational alterations with regard to the parent peptide and spatial hindrances between these both compounds and DP IV can explain the loss of inhibitory activity. Our data suggest that the N-terminal residues of HIV-1 Tat do interact directly with the active site of DP IV and that DP IV does mediate Tat's immunosuppressive effects. PMID- 9374516 TI - Cell-specific induction of apoptosis by microinjection of cytochrome c. Bcl-xL has activity independent of cytochrome c release. AB - Bcl-xL, an antiapoptotic member of the Bcl-2 family, inhibits programmed cell death in a broad variety of cell types. Recent reports have demonstrated that cytochrome c is released from mitochondria during apoptosis and have suggested that this release may be a critical step in the activation of proapoptotic caspases and subsequent cell death. Furthermore, it has been demonstrated that Bcl-2 can prevent the release of cytochrome c from mitochondria in cells triggered to undergo apoptosis. This has led to the hypothesis that the antiapoptotic effects of Bcl-2 family members are due specifically to their ability to prevent cytochrome c release thus preventing subsequent cytochrome c dependent caspase activation. In the present report, we use microinjection techniques to investigate the relationship between cytochrome c release, induction of apoptosis, and Bcl-xL activity in intact cells. We demonstrate that microinjection of cytochrome c into the cytosol of human kidney 293 cells results in a dose-dependent induction of apoptosis. In contrast, MCF7 breast carcinoma cells (stably transfected to express the Fas antigen CD95, and denoted MCF7F) that lack detectable levels of caspase 3 (CPP32), are totally resistant to microinjection of cytochrome c. However, transfection of MCF7F cells with an expression plasmid coding for pro-caspase 3, but not other pro-caspases, restores cytochrome c sensitivity. Although MCF7F cells are insensitive to cytochrome c microinjection, they rapidly undergo apoptosis in a caspase-dependent manner in response to either tumor necrosis factor or anti-Fas plus cycloheximide, and these deaths are strongly inhibited by Bcl-xL expression. Furthermore, microinjection of cytochrome c does not overcome these antiapoptotic effects of Bcl-xL. Our results support the concept that the release of cytochrome c into the cytoplasm can promote the apoptotic process in cells expressing pro-caspase 3 but that cytochrome c release is not sufficient to induce death in all cells. Importantly, the ability of Bcl-xL to inhibit cell death in the cytochrome c insensitive MCF7F cells cannot be due solely to inhibition of cytochrome c release from mitochondria. PMID- 9374515 TI - X-ray crystallographic studies of Candida albicans dihydrofolate reductase. High resolution structures of the holoenzyme and an inhibited ternary complex. AB - The recent rise in systemic fungal infections has created a need for the development of new antifungal agents. As part of an effort to provide therapeutically effective inhibitors of fungal dihydrofolate reductase (DHFR), we have cloned, expressed, purified, crystallized, and determined the three dimensional structure of Candida albicans DHFR. The 192-residue enzyme, which was expressed in Escherichia coli and purified by methotrexate affinity and cation exchange chromatography, was 27% identical to human DHFR. Crystals of C. albicans DHFR were grown as the holoenzyme complex and as a ternary complex containing a pyrroloquinazoline inhibitor. Both complexes crystallized with two molecules in the asymmetric unit in space group P21. The final structures had R-factors of 0.199 at 1.85-A resolution and 0.155 at 1.60-A resolution, respectively. The enzyme fold was similar to that of bacterial and vertebrate DHFR, and the binding of a nonselective diaminopyrroloquinazoline inhibitor and the interactions of NADPH with protein were typical of ligand binding to other DHFRs. However, the width of the active site cleft of C. albicans DHFR was significantly larger than that of the human enzyme, providing a basis for the design of potentially selective inhibitors. PMID- 9374517 TI - Characterization and expression of the mouse lumican gene. AB - Lumican is one of the major keratan sulfate proteoglycans (KSPG) in vertebrate corneas. We previously cloned the murine lumican cDNA. This study determines the structure of murine lumican gene (Lum) and its expression during mouse embryonic developments. The mouse lumican gene was isolated from a bacterial artificial chromosome mouse genomic DNA library and characterized by polymerase chain reaction and Southern hybridization. The lumican gene spans 6.9 kilobase pairs of mouse genome. The gene consists of three exons and two introns. Exon 1 constitutes 88 bases (b) of untranslated sequence. Exon 2 is 883 b and contains most of the coding sequence of lumican mRNA, and exon 3 has 152 b of coding sequence and 659 b of 3' noncoding sequence. The mouse lumican gene has a TATCA element, a presumptive TATA box, which locates 27 b 5'-upstream from the transcription initiation site. Northern hybridization and in situ hybridization indicate that in early stages of embryonic development, day 7 post coitus the embryo expresses little or no lumican. Thereafter, different levels of lumican mRNA can be detected in various organ systems, such as cornea stroma, dermis, cartilage, heart, lung, and kidney. The cornea and heart are the two tissues that have the highest expression in adult. Immunoblotting studies found that KSPG core proteins became abundant in the cornea and sclera by postnatal day 10 but that sulfated KSPG could not be detected until after the eyes open. These results indicate that lumican is widely distributed in most interstitial connective tissues. The modification of lumican with keratan sulfates in cornea is concurrent with eye opening and may contribute to corneal transparency. PMID- 9374518 TI - Isolation of a novel beta4 integrin-binding protein (p27(BBP)) highly expressed in epithelial cells. AB - The integrin beta4 has a long cytodomain necessary for hemidesmosome formation. A yeast two-hybrid screen using beta4 cytodomain uncovered a protein called p27(BBP) that represents a beta4 interactor. Both in yeast and in vitro, p27(BBP) binds the two NH2-terminal fibronectin type III modules of beta4, a region required for signaling and hemidesmosome formation. Sequence analysis of p27(BBP) revealed that p27(BBP) was not previously known and has no homology with any isolated mammalian protein, but 85% identical to a yeast gene product of unknown function. Expression studies by Northern analysis and in situ hybridization showed that, in vivo, p27(BBP) mRNA is highly expressed in epithelia and proliferating embryonic epithelial cells. An antibody raised against p27(BBP) COOH-terminal domain showed that all beta4-containing epithelial cell lines expressed p27(BBP). The p27(BBP) protein is insoluble and present in the intermediate filament pool. Furthermore, subcellular fractionation indicated the presence of p27(BBP) both in the cytoplasm and in the nucleus. Confocal analysis of cultured cells showed that part of p27(BBP) immunoreactivity was both nuclear and in the membrane closely apposed to beta4. These results suggest that the p27(BBP) is an in vivo interactor of beta4, possibly linking beta4 to the intermediate filament cytoskeleton. PMID- 9374519 TI - Regulation of CD44-protein 4.1 interaction by Ca2+ and calmodulin. Implications for modulation of CD44-ankyrin interaction. AB - Erythrocyte membrane skeletal protein 4.1 isoforms have been identified in a variety of non-erythroid cells. However, interactions between protein 4.1 and its binding partners in non-erythroid cell membranes are poorly understood. In the erythrocyte membrane, protein 4.1 binds to the cytoplasmic domain of band 3 and, through this interaction, modulates ankyrin binding to band 3. The sequences LRRRY or IRRRY in band 3 mediate the interaction between band 3 and protein 4.1. The cytoplasmic domain of CD44, a transmembrane glycoprotein found in erythroid as well as non-erythroid cells, has internal sequences SRRRC and QKKKL. We wanted to determine if protein 4.1 binds to CD44 in a fashion analogous to its binding to band 3 and through this interaction modulates ankyrin binding to CD44. We report here that protein 4.1 binds to the cytoplasmic domain of CD44 with a dissociation constant on the order of 10(-7) M and that Ca2+ and calmodulin reduce the affinity of this interaction. Furthermore, although independent binding of both protein 4.1 and ankyrin to CD44 could be documented, binding of protein 4.1 prevented subsequent ankyrin binding. These studies have enabled us to identify a potentially important functional role for protein 4.1 in modulating ankyrin binding to CD44. PMID- 9374520 TI - Molecular cloning of a new aquaporin from rat pancreas and liver. AB - A new water channel (aquaporin-8, gene symbol AQP8) was isolated from rat pancreas and liver by homology cloning. Ribonuclease protection assay showed intense expression of the gene in pancreas and liver, less intense in colon and salivary gland, and negligible in other organs. The full-length cDNA was obtained by ligation of approximately 1.4-kilobase (kb) cDNA isolated from the rat liver cDNA library to approximately 0.5 kb of the 5'-end fragment obtained by the rapid amplification of cDNA ends method. A major transcript of approximately 1.45 kb was demonstrated in liver and colon by Northern blot analysis. Expression of the cRNA in Xenopus oocytes markedly enhanced osmotic water permeability in a mercury sensitive manner, indicating a water channel function of this molecule. The open reading frame encoded a 263-amino acid protein with a predicted molecular size of 28 kDa. Hydropathy analysis represented six membrane-spanning domains and five connecting loops containing two sites of NPA motif as preserved in other aquaporins. Unlike other mammalian aquaporins, AQP8 has an unusual structure with a long N terminus and a short C terminus, which are found in plant aquaporin, gamma-tonoplast intrinsic protein. By in situ hybridization, AQP8 mRNA expression was assumed in hepatocytes, acinal cells of pancreas and salivary gland, and absorptive colonic epithelial cells. The physiological role(s) of AQP8 remain to be elucidated. PMID- 9374521 TI - Insulin receptor substrate (IRS)-1 and IRS-2 are tyrosine-phosphorylated and associated with phosphatidylinositol 3-kinase in response to brain-derived neurotrophic factor in cultured cerebral cortical neurons. AB - Brain-derived neurotrophic factor (BDNF), a member of the neurotrophins, promotes differentiation and survival of various types of neurons in the central nervous system. BDNF binds to and activates the tyrosine kinase receptor, TrkB, initiating intracellular signaling and exerting its effects. Phosphatidylinositol 3-kinase (PI3-K), which has been implicated in promotion of neuronal survival by neurotrophic factors, is a component in the signaling pathway of BDNF. We examined how BDNF activates PI3-K in cultured cerebral cortical neurons. We found that insulin receptor substrate (IRS)-1 and -2 are involved in the BDNF signaling pathway that activates PI3-K. IRS-1 and -2 were tyrosine-phosphorylated and bound to PI3-K in response to BDNF. This BDNF-stimulated signaling via IRS-1 and -2 was inhibited by K-252a, an inhibitor of Trk tyrosine kinase. In addition, signaling via IRS-1 and -2 was markedly sustained as well as the BDNF-induced tyrosine phosphorylation of TrkB. On the other hand, we observed no association of PI3-K with TrkB in response to BDNF. These results indicate that the activation of TrkB by BDNF induces the activation of PI3-K via IRS-1 and -2 rather than by a direct interaction of TrkB with PI3-K in cultured cortical neurons. PMID- 9374522 TI - The solution structure of the pleckstrin homology domain of human SOS1. A possible structural role for the sequential association of diffuse B cell lymphoma and pleckstrin homology domains. AB - A large subset of pleckstrin homology (PH) domains are immediately to the C terminus of diffuse B cell lymphoma (Dbl) homology (DbH) domains. Dbl domains are generally considered to be GTPase-exchange factors; many are proto-oncogenes. PH domains appear to function as membrane-recruitment factors, or have specific protein-protein interactions. Since dual domain (DbH/PH) constructs are known to have significant properties in other pathways, it is possible that a defined interdomain relationship is required for DbH/PH function. We determined the solution structure of the human SOS1 PH domain for a construct partially extended into the preceding DbH domain. There are specific structural contacts between the PH and the vestigial DbH domain. This appears to involve structural elements common to this subfamily of PH domains, and to DbH domains. The human SOS1 PH domain binds to inositol 1,4,5-triphosphate with a approximately 60 mu M affinity. Using chemical shift titration, the binding site is identified to be essentially identical to that observed crystallographically for the inositol 1,4,5-triphosphate complex with the PH domain of phospholipase Cdelta. This site may serve as an interdomain regulator of DbH or other domains' functions. While the overall fold of the human SOS1 PH domain is similar to other PH domains, the size and position of the intrastrand loops and the presence of an N-terminal alpha-helix of the vestigial DbH domain suggest that the subfamily of PH domains associated with DbH domains may be a well defined structural group in which the PH domain is a membrane recruiter and modulator. PMID- 9374523 TI - Conserved properties between functionally distinct MutS homologs in yeast. AB - In the yeast Saccharomyces cerevisiae there are five nuclear MutS homologs that act in two distinct processes. MSH2, 3, and 6 function in mismatch repair in both vegetative and meiotic cells, whereas MSH4 and MSH5 act specifically to facilitate crossovers between homologs during meiosis. Coimmunoprecipitation as well as two-hybrid experiments indicate that the Msh4 and Msh5 proteins form a hetero-oligomeric structure similar to what is observed for the Msh proteins involved in mismatch repair. Mutation of conserved amino acids in the NTP binding and putative helix-turn-helix domains of Msh5p abolish function but are still capable of interaction with Msh4p, suggesting that NTP binding plays a role downstream of hetero-oligomer formation. No hetero-oligomers are observed between the mismatch repair MutS proteins (Msh2p and Msh6p) and either Msh4p or Msh5p. These results indicate that one level of functional specificity between the mismatch repair and meiotic crossover MutS homologs in yeast is provided by the ability to form distinct hetero-oligomers. PMID- 9374524 TI - The cysteine-peptidase bleomycin hydrolase is a member of the galactose regulon in yeast. AB - Bleomycin hydrolase is a cysteine peptidase discovered through its ability to detoxify the anti-cancer glycopeptide, bleomycin. Although found in all tissues in mammals and in both eukaryotes and prokaryotes, the normal cellular function of this peptidase is not known. We had previously reported the purification of bleomycin hydrolase from yeast based on its unexpected ability to bind DNA. Recently we collaborated in solving the crystal structure of this protein, revealing a hexameric ring organization. We now report that the molecular characterization of the gene encoding yeast bleomycin hydrolase is also surprising. The transcription of the gene is regulated by galactose. Furthermore, this regulation is conveyed by a binding site for the Gal4 regulatory protein in its promoter, prompting the designation of this gene as GAL6. Gal6p also appears to have a negative effect on the GAL system as a deletion of the gene leads to a 2-5-fold higher expression of the GAL1, GAL2, GAL7, and MEL1 genes. The GAL6 deletion does not affect the expression of another inducible gene, HSP26. Neither the peptidase nor the nucleic acid binding activity of Gal6p as assayed is apparently required to convey this regulation, implying yet another function for this new member of the GAL regulon. PMID- 9374525 TI - Antioxidant-induced nuclear translocation of CCAAT/enhancer-binding protein beta. A critical role for protein kinase A-mediated phosphorylation of Ser299. AB - Alterations in intracellular oxidative status activate several signal transduction pathways resulting in distinct patterns of gene expression. Treatment of colorectal cancer cells with antioxidants can lead to apoptosis by induction of p21 through a mechanism involving CCAAT/enhancer-binding protein beta (C/EBPbeta). Herein, we demonstrate that the antioxidant pyrrolidinedithiocarbamate activates cAMP-dependent protein kinase (PKA) in a colorectal cancer cell line DKO-1. Activation of PKA phosphorylates Ser299 within C/EBPbeta, which is essential for protein translocation to the nucleus. Pharmacological inhibition of PKA and mutation of Ser299 to alanine blocks C/EBPbeta nuclear translocation and induction of p21. Our results indicate that a cAMP-dependent phosphorylation of C/EBPbeta at Ser299 is critical for nuclear translocation of this protein and its subsequent transactivation of genes in response to antioxidant treatment. PMID- 9374526 TI - Prenylation-dependent association of Ki-Ras with microtubules. Evidence for a role in subcellular trafficking. AB - We recently identified a prenyl peptide-binding protein in microsomal membranes from bovine brain (Thissen, J. A., and Casey, P. J. (1993) J. Biol. Chem. 268, 13780-13783). Through a variety of approaches, this binding protein has been identified as the cytoskeletal protein tubulin. Prenyl peptides bind to purified tubulin with a Kd of 40 nM and also bind to tubulin polymerized into microtubules. Microtubule affinity chromatography of extracts from cells in which the prenyl protein pool was metabolically labeled revealed that prenyl proteins bound to the immobilized microtubules; one, a 24-kDa protein, was tentatively identified as a GTP-binding protein. Of several prenylated GTP-binding proteins tested, including Ki-Ras4B, Ha-Ras, RhoB, RhoA, and Rap1B, only Ki-Ras was found to bind significantly to microtubules, and this was in a prenylation-dependent fashion. A potential significance of the interaction of Ki-Ras4B with microtubules was indicated from analysis of the localization of newly synthesized Ki-Ras4B and Ha-Ras, each tagged with green fluorescence protein (GFP). Treatment of NIH-3T3 cells expressing GFP-Ki-Ras with Taxol (paclitaxel) resulted in accumulation of the expressed protein in intracellular locations, whereas in control cells the protein was correctly targeted to the plasma membrane. Importantly, such treatment with paclitaxel did not affect the cellular localization of expressed GFP-Ha-Ras. These results indicate that an intact microtubule network may be directly involved in Ki-Ras processing and/or targeting and provide direct evidence for a physiological distinction between Ki Ras and Ha-Ras in cells. Additionally, the finding that paclitaxel treatment of cells disrupts Ki-Ras trafficking suggests an additional mechanism for the anti proliferative effects of this drug. PMID- 9374527 TI - Tumor necrosis factor increases hepatocellular glutathione by transcriptional regulation of the heavy subunit chain of gamma-glutamylcysteine synthetase. AB - Tumor necrosis factor (TNF) is an inflammatory cytokine that causes cell injury by generation of oxidative stress. Since glutathione (GSH) is a key cellular antioxidant that detoxifies reactive oxygen species, the purpose of our work was to examine the regulation of cellular GSH, the expression of heavy subunit chain of gamma-glutamylcysteine synthetase (gamma-GCS-HS), and control of intracellular generation of reactive oxygen species in cultured rat hepatocytes treated with TNF. Exposure of cells to TNF (10,000 units/ml) resulted in depletion of cellular GSH levels (50-70%) and overproduction of hydrogen peroxide (2-3-fold) and lipid peroxidation. However, cells treated with lower doses of TNF (250-500 units/ml) exhibited increased levels of GSH (60-80% over control). TNF treatment increased (70-100%) the levels of gamma-GCS-HS mRNA, the catalytic subunit of the regulating enzyme in GSH biosynthesis. Furthermore, intact nuclei isolated from hepatocytes treated with TNF transcribed the gamma-GCS-HS gene to a greater extent than control cells, indicating that TNF regulates gamma-GCS-HS at the transcriptional level. The capacity to synthesize GSH de novo determined in cell free extracts incubated with GSH precursors was greater (50-70%) in hepatocytes that were treated with TNF; however, the activity of GSH synthetase remained unaltered by TNF treatment indicating that TNF selectively increased the activity of gamma-GCS. Despite activation of nuclear factor-kappaB (NF-kappaB) by TNF, this transcription factor was not required for TNF-induced transcription of gamma GCS-HS as revealed by deletion constructs of the gamma-GCS-HS promoter subcloned in a chloramphenicol acetyltransferase reporter vector and transfected into HepG2 cells. In contrast, a construct containing AP-1 like/metal response regulatory elements increased chloramphenicol acetyltransferase activity upon exposure to TNF. Thus, TNF increases hepatocellular GSH levels by transcriptional regulation of gamma-GCS-HS gene, probably through AP-1/metal response element-like binding site(s) in its promoter, which may constitute a protective mechanism in the control of oxidative stress induced by inflammatory cytokines. PMID- 9374528 TI - Identification of a ganglioside recognition domain of tetanus toxin using a novel ganglioside photoaffinity ligand. AB - Tetanus toxin entry into vertebrate motorneurons may involve binding of neuronal surface gangliosides containing the "1b" substructure (a NeuAcalpha2,8NeuAc group on an internal galactose residue). The domains of tetanus toxin involved in ganglioside binding are known to reside within the carboxyl-terminal half of the toxin's heavy chain ("C fragment"). We developed a novel photoaffinity reagent based upon the structure of the 1b ganglioside GD1b (125I-azido-GD1b) to define the ganglioside-binding domains of tetanus toxin. Using this ligand, we observed radiolabeling of tetanus toxin C fragment which could be specifically inhibited by a ganglioside of the 1b series (GT1b), but not by a non-1b series ganglioside (GM3). When tetanus toxin C fragment was proteolyzed with clostripain, whether before or after reaction with 125I-azido-GD1b, a radiolabeled band was observed by SDS-polyacrylamide gel electrophoresis autoradiography, which was selectively inhibited by GT1b. Protein sequencing of proteolyzed tetanus toxin C fragment co migrating with that band revealed the carboxyl-terminal 34 amino acid residues of tetanus toxin. Matrix-assisted laser desorption/ionization mass spectrometry of a photoaffinity labeled synthetic polypeptide representing the 34-amino acid domain revealed modification at a single residue (His1293). We propose that this domain of tetanus toxin is sufficient for ganglioside binding. PMID- 9374529 TI - Characterization of multiple enhancer regions upstream of the apolipoprotein(a) gene. AB - Plasma concentrations of the atherogenic lipoprotein(a) (Lp(a)) are predominantly determined by inherited sequences within or closely linked to the apolipoprotein(a) gene locus. Much of the interindividual variability in Lp(a) levels is likely to originate at the level of apo(a) gene transcription. However, the liver-specific apo(a) basal promoter is extremely weak and does not exhibit common functional variations that affect plasma Lp(a) concentrations. In a search for additional apo(a) gene control elements, we have identified two fragments with enhancer activity within the 40-kilobase pair apo(a)-plasminogen intergenic region that coincide with DNase I-hypersensitive sites (DHII and DHIII) observed in liver chromatin of mice expressing a human apo(a) transgene. Neither enhancer exhibits tissue specificity. DHIII activity was mapped to a 600-base pair fragment containing nine DNase I-protected elements (footprints) that stimulates luciferase expression from the apo(a) promoter 10-15-fold in HepG2 cells. Binding of the ubiquitous transcription factor Sp1 plays a major role in the function of this enhancer, but no single site was indispensable for activity. DHIII comprises part of the regulatory region of an inactive long interspersed nucleotide element 1 retrotransposon, raising the possibility that retrotransposon insertion can influence the regulation of adjacent genes. DHII enhancer activity was localized to a 180-base pair fragment that stimulates transcription from the apo(a) promoter 4-8-fold in HepG2 cells. Mutations within an Sp1 site or either of two elements composed of direct repeats of the nuclear hormone receptor half-site AGGTCA in this sequence completely abolished enhancer function. Both nuclear hormone receptor elements were shown to bind peroxisome proliferator-activated receptors and other members of the nuclear receptor family, suggesting that this enhancer may mediate drug and hormone responsiveness. PMID- 9374530 TI - Thioredoxin is transcriptionally induced upon activation of heat shock factor 2. AB - Heat shock gene expression is differentially regulated in cells exposed to stress stimuli and in cells undergoing processes of differentiation and development. Regulation of the classical heat shock response is mediated by heat shock factor 1 (HSF1), whereas heat shock factor 2 (HSF2) is activated in certain differentiating cells, for example during hemin-mediated differentiation of human K562 erythroleukemia cells. Hence, the signaling pathways leading to induction of heat shock gene expression upon different stimuli are likely to be distinct. We have used RNA arbitrarily primed polymerase chain reaction to identify genes that are differentially regulated upon activation of HSF1 and HSF2. In this study, we report that thioredoxin (TRX) expression is induced in K562 cells in response to hemin in an HSF2-dependent manner. Increased TRX expression was primarily detected on the transcriptional level, subsequently leading to elevated TRX mRNA and protein levels. Hemin treatment caused no reduction in cellular glutathione concentrations, indicating that the increased TRX expression was not due to oxidative stress. Studies using cell lines where overexpression of the HSF2-beta isoform represses HSF2 activation implied that active HSF2 is required for transcriptional induction of TRX. Unlike HSF2, activation of HSF1 did not induce TRX expression. Taken together, our results suggest that HSF1 and HSF2 may regulate distinct target genes, and activation of HSF2 could be involved in the regulation of TRX expression during hemin-mediated differentiation of K562 cells. PMID- 9374531 TI - Equilibrium binding of estrogen receptor with DNA using fluorescence anisotropy. AB - Interaction of estrogen receptor (ER) with DNA sequences known as estrogen response elements (ERE) is required for estrogen regulation of the expression of target genes. To characterize the affinity and specificity of ER interaction with ERE sequences in vitro under equilibrium conditions, fluorescence anisotropy assays were performed using recombinant, purified ER and a fluorescein-labeled 35 base pair oligonucleotide bearing an idealized palindromic ERE. In buffer containing 100 mM KCl, the baculovirus-expressed, purified human ER bound with similar affinity to the consensus ERE and a mutant ERE with a single base pair change per half-site. Above 225 mM KCl, ER exhibited discrimination between the consensus and mutated ERE targets. Between 225 and 275 mM KCl, binding to the consensus ERE was independent of salt concentration and occurred with an equilibrium dissociation constant (Kd) of 1.8 +/- 0.6 nM, whereas binding to the mutant ERE was not detected at ER concentrations below 100 nM under the same conditions. At 300 mM KCl, the Kd for the consensus ERE increased approximately 25-fold, suggesting complex salt concentration dependence. Both estrogen-occupied and unoccupied ER bound to the consensus ERE sequence with similar affinity, indicating that estrogen affects ER activity at a step other than DNA binding. Unlike the full-length ER, the recombinant DNA binding domain of ER did not discriminate between the consensus and mutated ERE sequences even at buffer salt concentrations greater than 200 mM NaCl, suggesting that ER sequences outside the DNA binding domain may be important in promoting specific binding. PMID- 9374532 TI - Interaction of NF-kappaB and NFAT with the interferon-gamma promoter. AB - Interferon-gamma (IFN-gamma) is a pleiotropic lymphokine whose production is restricted to activated T cells and NK cells. Along with other cytokines, IFN gamma gene expression is inhibited by the immunosuppressant cyclosporin A. We have previously identified an intronic enhancer region (C3) of the IFN-gamma gene that binds the NF-kappaB protein c-Rel and that shows partial DNA sequence homology with the cyclosporin A-sensitive NFAT binding site and the 3'-half of the NF-kappaB consensus site. Sequence analysis of the IFN-gamma promoter revealed the presence of two additional C3-related elements (C3-1P and C3-3P). In addition, an NF-kappaB site (IFN-gamma kappaB) was identified within the promoter region. Based on this observation, we have analyzed the potential role of NF kappaB and NFAT family members in regulating IFN-gamma transcription. Electrophoretic mobility shift assay analysis demonstrated that after T cell activation, the p50 and p65 NF-kappaB subunits bind specifically to the newly identified IFN-gamma kappaB and C3-related sites. In addition, we identified the NFAT proteins as a component of the inducible complexes that bind to the C3-3P site. Site-directed mutagenesis and transfection studies demonstrate that calcineurin-inducible transcriptional factors enhance the transcriptional activity of the IFN-gamma promoter through the cyclosporin-sensitive C3-3P site, whereas NF-kappaB proteins functionally interact with the C3-related sites. In addition, when located downstream to the beta-galactosidase gene driven by the IFN-gamma promoter, the intronic C3 site worked in concert with both the IFN gamma kappaB and the C3-3P site to enhance gene transcription. These results demonstrate that the coordinate activities of NFAT and NF-kappaB proteins are involved in the molecular mechanisms controlling IFN-gamma gene transcription. PMID- 9374533 TI - A sweat gland-derived differentiation activity acts through known cytokine signaling pathways. AB - The sympathetic innervation of sweat glands undergoes a target-induced noradrenergic to cholinergic/peptidergic switch during development. Similar changes are induced in cultured sympathetic neurons by sweat gland cells or by one of the following cytokines: leukemia inhibitory factor (LIF), ciliary neurotrophic factor (CNTF), or cardiotrophin-1 (CT-1). None of these is the sweat gland-derived differentiation activity. LIF, CNTF, and CT-1 act through the known receptors LIF receptor beta (LIFRbeta) and gp130 and well defined signaling pathways including receptor phosphorylation and STAT3 activation. Therefore, to determine whether the gland-derived differentiation activity was a member of the LIF/CNTF cytokine family, we tested whether it acted via these same receptors and signal cascades. Blockade of LIFRbeta inhibited the sweat gland differentiation activity in neuron/gland co-cultures, and extracts of gland-containing footpads stimulated tyrosine phosphorylation of LIFRbeta and gp130. An inhibitor (CGX) of molecules that bind the CNTFRalpha, which is required for CNTF signaling, did not affect the gland-derived differentiation activity. Soluble footpad extracts induced the same changes in NBFL neuroblastoma cells as LIF and CNTF, including increased vasoactive intestinal peptide mRNA, STAT3 dimerization, and DNA binding, and stimulation of transcription from the vasoactive intestinal peptide cytokine-responsive element. Thus, the sweat gland-derived differentiation activity uses the same signaling pathway as the neuropoietic cytokines, and is likely to be a family member. PMID- 9374534 TI - Interaction of a receptor tyrosine kinase, EGF-R, with caveolins. Caveolin binding negatively regulates tyrosine and serine/threonine kinase activities. AB - Caveolin, a 21-24-kDa integral membrane protein, is a principal component of caveolae membranes. We and others have suggested that caveolin functions as a scaffolding protein to organize and concentrate certain caveolin-interacting signaling molecules within caveolae membranes. In this regard, it has been shown that a 20-amino acid membrane-proximal region of the cytosolic NH2-terminal domain of caveolin is sufficient to mediate the interaction of caveolin with signaling proteins, namely G-proteins, Src-like kinases, eNOS, and H-Ras. This caveolin-derived protein domain has been termed the caveolin-scaffolding domain. Binding of the caveolin-scaffolding domain functionally suppresses the activity of G-protein alpha subunits, eNOS, and Src-like kinases, suggesting that caveolin binding may also play a negative regulatory role in signal transduction. Here, we report the direct interaction of caveolin with a growth factor receptor, EGF-R, a known caveolae-associated receptor tyrosine kinase. Two consensus caveolin binding motifs have been previously defined using phage display technology. One of these motifs is present within the conserved kinase domains of most known receptor tyrosine kinases (termed region IX). We now show that this caveolin binding motif within the kinase domain of the EGF-R can mediate the interaction of the EGF-R with the scaffolding domains of caveolins 1 and 3 but not with caveolin 2. In addition, the scaffolding domains of caveolins 1 and 3 both functionally inhibit the autophosphorylation of the EGF-R kinase in vitro. Importantly, this caveolin-mediated inhibition of the EGF-R kinase could be prevented by the addition of an EGF-R-derived peptide that (i) contains a well conserved caveolin binding motif and (ii) is located within the kinase domain of the EGF-R and most known receptor tyrosine kinases. Similar results were obtained with protein kinase C, a serine/threonine kinase, suggesting that caveolin may function as a general kinase inhibitor. The implications of our results are discussed within the context of caveolae-mediated signal transduction. In this regard, caveolae-coupled signaling might explain how linear signaling pathways can branch and interconnect extensively, forming a signaling module or network. PMID- 9374535 TI - The sorting route of cytochrome b2 branches from the general mitochondrial import pathway at the preprotein translocase of the inner membrane. AB - Cytochrome b2 is synthesized in the cytosol with a bipartite presequence. The first part of the presequence targets the protein to mitochondria and mediates translocation into the mitochondrial matrix compartment; the second part contains the sorting signal that is required for delivery of the protein to the intermembrane space. The localization of the structures that recognize the sorting signal is unclear. Here we show that upon import in vivo, the sorting signal of cytochrome b2 causes an early divergence from the general matrix import pathway and thereby prevents translocation of a folded C-terminal domain into mitochondria. By co-immunoprecipitations we find that translocation intermediates of cytochrome b2 are associated with Tim23, a component of the inner membrane protein import machinery. Cytochrome b2 constructs with an alteration in the sorting signal are mistargeted to the matrix of wild-type mitochondria. In mitochondria containing a mutant form of Tim23, however, the translocation of the altered sorting signal across the inner membrane is inhibited, and cytochrome b2 is correctly sorted to the intermembrane space. We suggest that the sorting signal of cytochrome b2 is recognized within the inner membrane in close vicinity to Tim23. PMID- 9374536 TI - Expression, purification, and regulation of two isoforms of the inositol 1,4,5 trisphosphate 3-kinase. AB - The level of inositol 1,4,5-trisphosphate in the cytoplasm is tightly regulated by two enzymes, the inositol 1,4,5,5-phosphatase and the inositol 1,4,5 trisphosphate 3-kinase. Two isoforms of the inositol 1,4,5-trisphosphate 3-kinase have been identified, the A form and the B form. The regulatory properties of the two isoforms were compared following overexpression and purification of the proteins from a v-src transformed mammalian cell line. The highly purified, recombinant inositol 1,4,5-trisphosphate 3-kinases were differentially regulated by calcium/calmodulin and via phosphorylation by protein kinase C or the cyclic AMP-dependent protein kinase. Both enzymes had similar affinities for inositol 1,4, 5-trisphosphate (Km 2-5 mu M). Calcium/calmodulin stimulated the activity of isoform A about 2.5-fold, whereas the activity of isoform B was increased 20 fold. The cyclic AMP-dependent protein kinase phosphorylated the inositol 1,4,5 trisphosphate 3-kinase A to the extent of 0.9 mol/mol and isoform B to 1 mol/mol. Protein kinase C phosphorylated isoform A to the extent of 2 mol/mol and isoform B to 2.7 mol/mol. Phosphorylation of isoform A by the cyclic AMP-dependent protein kinase caused a 2.5-fold increase in its activity when assayed in the absence of calcium/calmodulin, whereas phosphorylation by protein kinase C decreased activity by 72%. The activity of isoform B in the absence of calcium/calmodulin was not affected by phosphorylation using either kinase. When assayed in the presence of calcium/calmodulin, phosphorylation of isoform A by the cyclic AMP-dependent protein kinase increased activity 1.5-fold, whereas phosphorylation of isoform B decreased activity by 45%. Phosphorylation of either isoform A or B by protein kinase C resulted in a 70% reduction of calcium/calmodulin-stimulated activity. Differential expression and regulation of the two inositol 1,4,5-trisphosphate 3-kinase isoforms provides multiple mechanisms for regulating the cytosolic level of inositol 1,4,5-trisphosphate in cells. PMID- 9374537 TI - Fluid shear stress activation of focal adhesion kinase. Linking to mitogen activated protein kinases. AB - Shear stress, the tangential component of hemodynamic forces, activates the extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK) signal transduction pathways in cultured vascular endothelial cells to induce the transcriptional activation of many immediate early genes. It appears that integrins, protein-tyrosine kinases, and the structural integrity of actin are important factors involved in these shear stress-induced responses. The underlying molecular events were investigated by the application of a shear stress of 12 dyn/cm2 on bovine aortic endothelial cells (BAEC). We found that such a shear stress increased the tyrosine phosphorylation and the kinase activity of focal adhesion kinase (FAK) and its association with growth factor receptor binding protein 2 (Grb2) in a rapid and transient manner, suggesting that FAK may be linked to these mitogen-activated protein kinase signaling pathways through a Grb2. Son of sevenless (Sos) complex. FAK(F397Y), which encodes a dominant negative mutant of FAK, attenuated the shear stress-induced kinase activity of Myc epitope-tagged ERK2 and hemagglutinin epitope-tagged JNK1. DeltamSos1, encoding a dominant negative mutant of Sos in which the guanine nucleotide exchange domain has been deleted, also attenuated shear stress activation of Myc-ERK2 and hemagglutinin-JNK1. Pretreating the confluent BAEC monolayers with a blocking type anti-vitronectin receptor monoclonal antibody had similar inhibitory effects in these shear stress-activated ERKs and JNKs. Confocal microscopic observation further demonstrated that FAK tended to cluster with vitronectin receptor near the abluminal side of the sheared BAEC. These results demonstrate that FAK signaling is critical in the shear stress-induced dual activation of ERK and JNK. PMID- 9374538 TI - RTX toxins recognize a beta2 integrin on the surface of human target cells. AB - Actinobacillus actinomycetemcomitans leukotoxin and Escherichia coli alpha hemolysin are RTX toxins that kill human immune cells. We have obtained a monoclonal antibody (295) to a cell surface molecule present on toxin-sensitive HL60 cells that can inhibit cytolysis by both RTX toxins. Utilization of this monoclonal antibody for immunoaffinity purification of detergent-solubilized target cell membranes yielded two polypeptide chains of approximate molecular masses of 100 and 170 kDa. Microsequencing of tryptic peptides from the two proteins showed complete homology with CD11a and CD18, the two subunits of the beta2 integrin, lymphocyte function-associated antigen 1 (LFA-1). Anti-CD11a and CD18 monoclonal antibodies also inhibited RTX toxin-mediated cytolysis. Direct binding experiments demonstrated the ability of an immobilized RTX to bind LFA-1 heterodimers present in a detergent lysate of human HL60 target cells. Transfection of CD11a and CD18 integrin genes into a cell line (K562) that is not sensitive to either RTX toxin resulted in LFA-1 expressing cells, KL/4, that were sensitive to both toxins. These experiments identify LFA-1 as a cell surface receptor that mediates toxicity of members of this family of pore-forming toxins. PMID- 9374539 TI - Resistance to diverse drugs and ultraviolet light conferred by overexpression of a novel human 26 S proteasome subunit. AB - We have investigated the usefulness of the fission yeast Schizosaccharomyces pombe as a model organism for the discovery of novel modes of drug resistance in human cells. In fission yeast, overexpression of the essential pad1(+) gene confers pleiotropic drug resistance through a pathway involving an AP-1 transcription factor encoded by pap1(+). We have identified POH1, a human pad1 homologue that can substitute fully for pad1(+) and induce AP-1-dependent drug resistance in fission yeast. POH1 also confers P-glycoprotein-independent resistance to taxol (paclitaxel), doxorubicin, 7-hydroxystaurosporine, and ultraviolet light when transiently overexpressed in mammalian cells. Poh1 is a previously unidentified component of the human 26 S proteasome, a multiprotein complex that degrades proteins targeted for destruction by the ubiquitin pathway. Hence, Poh1 is part of a conserved mechanism that determines cellular susceptibility to cytotoxic agents, perhaps by influencing the ubiquitin dependent proteolysis of transcription factors. PMID- 9374540 TI - Phosphorylation of light-harvesting complex II and photosystem II core proteins shows different irradiance-dependent regulation in vivo. Application of phosphothreonine antibodies to analysis of thylakoid phosphoproteins. AB - An immunological approach using a polyclonal phosphothreonine antibody is introduced for the analysis of thylakoid protein phosphorylation in vivo. Virtually the same photosystem II (PSII) core phosphoproteins (D1, D2, CP43, and the psbH gene product) and the light-harvesting chlorophyll a/b complex II (LHCII) phosphopolypeptides (LHCB1 and LHCB2), as earlier identified by radiolabeling experiments, were recognized in both pumpkin and spinach leaves. Notably, the PSII core proteins and LHCII polypeptides were found to have a different phosphorylation pattern in vivo with respect to increasing irradiance. Phosphorylation of the PSII core proteins in leaf discs attained the saturation level at the growth light intensity, and this level was also maintained at high irradiances. Maximal phosphorylation of LHCII polypeptides only occurred at low light intensities, far below the growth irradiance, and then drastically decreased at higher irradiances. These observations are at variance with traditional studies in vitro, where LHCII shows a light-dependent increase in phosphorylation, which is maintained even at high irradiances. Only a slow restoration of the phosphorylation capacity for LHCII polypeptides at the low light conditions occurred in vivo after the high light-induced inactivation. Furthermore, if thylakoid membranes were isolated from the high light-inactivated leaves, no restoration of LHCII phosphorylation took place in vitro. However, both the high light-induced inactivation and low light-induced restoration of LHCII phosphorylation seen in vivo could be mimicked in isolated thylakoid membranes by incubating with reduced and oxidized dithiothreitol, respectively. We propose that stromal components are involved in the regulation of LHCII phosphorylation in vivo, and inhibition of LHCII phosphorylation under increasing irradiance results from reduction of the thiol groups in the LHCII kinase. PMID- 9374541 TI - Constitutive protection of E2F recognition sequences in the human thymidine kinase promoter during cell cycle progression. AB - The sequences responsible for S phase-specific induction of the human thymidine kinase (TK) gene have been mapped to a small region that contains putative E2F binding sites. We have analyzed protein-DNA interactions at the TK promoter during cell cycle progression in human fibroblasts using an in vivo footprinting approach. We found 14 protein binding sites that were occupied in vivo. All of the sites (among them two inverted CCAAT boxes and several Sp1 sites) bound transcription factors constitutively throughout the cell cycle, i.e. none of the factor binding was cell cycle-dependent. An E2F-like site located between nucleotides -97 and -89 relative to the major transcription start site was protected in G0, G1, S, and G2 phases. This cell cycle-independent protection of E2F sequences in the TK promoter differs from the G0/G1-restricted binding of E2F complexes observed for genes in which the E2F sites function as repressor elements (Tommasi, S., and Pfeifer, G. P. (1995) Mol. Cell. Biol. 15, 6901-6913; Zwicker, J., Liu, N., Engeland, K., Lucibello, F. C., and Muller, R. (1996) Science 271, 1595-1597). A comparison of several genes containing E2F motifs indicates that E2F sites located in proximity to the transcription initiation site (-50 to +20) in TATA-less promoters predominantly function as repressor elements, while in other genes constitutively bound E2F complexes located further upstream mediate activation presumably in conjunction with a functional TATA box. PMID- 9374542 TI - Mitogenic activation, phosphorylation, and nuclear translocation of protein kinase Bbeta. AB - Protein kinase B (PKB) is a member of the second messenger-dependent family of serine/threonine kinases that has been implicated in signaling pathways downstream of growth factor receptor tyrosine kinases and phosphatidylinositol 3 kinase. Here we report the characterization of the human beta-isoform of PKB (PKBbeta). PKBbeta is ubiquitously expressed in a number of human tissues, with mRNA and protein levels elevated in heart, liver, skeletal muscle, and kidney. After transfection into HEK-293 or COS-1 cells, PKBbeta is activated 2- to 12 fold by mitogens and survival factors. Activation was due to phosphorylation on Thr-309 and Ser-474, which correspond to Thr-308 and Ser-473 implicated in the regulation of PKBalpha. Both phosphorylation and activation were prevented by the phosphatidylinositol 3-kinase inhibitor wortmannin. Moreover, membrane-targeted PKBbeta was constitutively activated when overexpressed in HEK-293 cells. Although the specific activity of PKBbeta was lower than that of PKBalpha toward Crosstide as a substrate (23 nmol/min/mg compared with 178 nmol/min/mg for PKBalpha), both enzymes showed similar substrate specificities. Using confocal microscopy, we show that activation of PKBbeta results in its nuclear translocation within 20 to 30 min after stimulation. These observations provide evidence that PKBbeta undergoes nuclear translocation upon mitogenic activation and support a role for PKB in signaling from receptor tyrosine kinases to the nucleus through phosphatidylinositol 3-kinase. PMID- 9374543 TI - Reconstitution of high affinity IgE receptor-mediated secretion by transfecting protein tyrosine kinase pp125FAK. AB - To study the role of the focal adhesion tyrosine kinase (FAK) in receptor mediated secretion, we transfected FAK cDNA into a variant (3B6) of the RBL-2H3 mast cell line. This 3B6 cell line expressed low levels of FAK and was defective in high affinity IgE receptor (FcepsilonRI) but not Ca2+ ionophore-mediated secretion. FcepsilonRI-mediated secretion was reconstituted after transfection of wild-type FAK. Histamine release was also enhanced by the stable expression of two mutants of FAK: a kinase-inactive form in which the ATP binding site Lys-454 was replaced by Arg or a mutant in which the autophosphorylation site Tyr-397 was replaced by Phe. Therefore, the catalytic activity and the autophosphorylation site of FAK are not essential for secretion. FcepsilonRI aggregation increased the tyrosine phosphorylation of both mutants of FAK to the same extent as wild type FAK. Therefore, tyrosine kinases activated by FcepsilonRI aggregation are phosphorylating FAK and some of these phosphorylation sites are other than Tyr 397. These results strongly suggest that FAK plays a role in FcepsilonRI-induced secretion by functioning as an adapter or linker molecule. PMID- 9374544 TI - Cytosolic 85-kDa phospholipase A2-mediated release of arachidonic acid is critical for proliferation of vascular smooth muscle cells. AB - Recent evidence suggests that arachidonic acid (AA) may be involved in regulating cellular proliferation. The predominant mechanism of AA release from cellular phospholipids is via phospholipase A2 (PLA2) hydrolysis. The purpose of this study was to examine the roles of the distinct 14-kDa and 85-kDa PLA2 enzymes in human coronary artery vascular smooth muscle cell (hCAVSMC) proliferation. Cultured hCAVSMCs proliferate in the presence of growth medium with a typical doubling time of 30-40 h, grow at a slower proliferative rate upon reaching confluency (day 8), and eventually undergo contact inhibition of growth (day 10). Neither Type II 14-kDa PLA2 activity nor mass changed over a 10-day culture period. In contrast, 85-kDa PLA2 protein activity and mRNA decreased as time in culture progressed. This reduction in 85-kDa PLA2 correlated with reductions in DNA synthesis and suggested a possible association between 85-kDa PLA2 and proliferation. To directly evaluate the role of the 85-kDa PLA2 in proliferation we examined the effects of an 85-kDa PLA2 inhibitor (AACOCF3) and 85-kDa PLA2 antisense oligonucleotides on proliferation. Both reagents dose dependently inhibited proliferation, whereas a 14-kDa PLA2 inhibitor (SB203347), a calcium independent PLA2 inhibitor (HELSS), an 85-kDa sense oligonucleotide, and a nonrelevant scrambled control oligonucleotide had no effect. The mechanism by which 85-kDa PLA2 influences cellular proliferation remains unclear. Inhibition of 85-kDa PLA2 activity produced neither phase-specific cell cycle arrest nor apoptosis (fluorescence-activated cell sorter analysis). Addition of AA (20 mu M) attenuated the effects of both AACOCF3 and 85-kDa antisense oligonucleotides implicating AA as a key mediator in cellular proliferation. However, although prostaglandin E2 (PGE2) was present in the culture medium, it peaked early (day 3) in culture, and indomethacin had no effect on cellular proliferation indicating that hCAVSMC proliferation was not mediated through PGE2. These data provide the first direct evidence that PLA2 is involved in control of VSMC proliferation and indicate that 85-kDa PLA2-mediated liberation of AA is critical for cellular proliferation. PMID- 9374545 TI - Isolation and characterization of mouse high-glycine/tyrosine proteins. AB - During hair follicle differentiation, several families of keratin proteins are synthesized sequentially. In the present study, cDNA clones encoding six members of mouse high-glycine/tyrosine protein were isolated by screening a cDNA library prepared from the mouse skin of an anagen phase with a differential hybridization technique. On the basis of their nucleotide and deduced amino acid sequences, they were found to encode two members of high-glycine/tyrosine protein type I and four of type II. Interestingly, one of the four type II proteins had been encoded by two distinct cDNAs. Among the cDNA clones isolated were included the ones encoding a new member of type I and II protein, respectively, which possessed an entire open reading frame. Novel type II protein, termed type II.4, with a molecular mass of 15,130 Da was revealed to have significant direct repeats and a cysteine residue at the carboxyl terminus, which indicates that this protein has characteristics intermediate between high-glycine/tyrosine proteins and cysteine rich proteins. In addition, the new member of type I protein has some features common with type II protein. We propose to term this protein type Ialpha until it is further characterized. Northern blot analysis demonstrated that gene expression of mouse high-glycine/tyrosine proteins followed the hair cycle growth fundamentally and reached its peak at day 9 in the first hair cycle, while two peaks of their expression were observed at day 33 and day 39 in the second cycle. Their transcripts were expressed in the cortical cells of hair follicles but not in the cells of the outer root sheath, inner root sheath, or medulla. Moreover, their gene expression commenced at different levels in cortical cells. The novel findings that each gene is activated transcriptionally with a distinct expression pattern spatially and temporally suggest that there is a remarkable difference in the distribution of these proteins in hair. PMID- 9374546 TI - Phosphatidylinositol 3-kinase and Ca2+ influx dependence for ligand-stimulated internalization of the c-Kit receptor. AB - We have evaluated the role of phosphatidylinositol 3-kinase (PI3-kinase) and Ca2+ influx in ligand-stimulated internalization of the c-Kit receptor. The wild type (wt) c-Kit receptor and YF719, a mutant receptor in which the SH2-mediated binding site for the p85 subunit of PI3-kinase is disrupted, were expressed in DA 1 cells. YF719 internalized with similar kinetics as wt c-Kit although the receptor remained localized close to the plasma membrane. However, in the absence of extracellular Ca2+, or in the presence of the competitive Ca2+ influx blocker Ni2+, the YF719 mutant failed to internalize. Failure to internalize in the absence of Ca2+ was also observed for the wt c-Kit receptor in cells that were pretreated with the PI3-kinase inhibitor, wortmannin. Following stimulation with ligand, clathrin heavy chains were found to co-immunoprecipitate with c-Kit. However, under conditions in which PI3-kinase activity is inhibited and Ca2+ influx is blocked, clathrin failed to co-immunoprecipitate with c-Kit. Our results demonstrate that both Ca2+ influx and PI3-kinase activity influence c-Kit endocytosis, and inhibition of these two signals disrupts the earliest stages of ligand-mediated internalization. PMID- 9374547 TI - Functional characterization of domains contained in hepatocyte growth factor-like protein. AB - To delineate the functional protein domains necessary for the biological activity of hepatocyte growth factor-like protein (HGFL), we created various site-directed and deletion mutated cDNAs coding for this protein. Wild-type and mutated versions of HGFL were produced after transfection of the corresponding cDNAs into tissue culture cells. The biological importance of the domains within HGFL was then examined by addition of recombinant wild-type or mutant forms of HGFL to assays aimed at elucidating regions involved in the stimulation of DNA synthesis, the induction of shape changes in macrophages, and the ability to stimulate cell scattering. Mutant proteins lacking the serine protease-like domain (light chain) were not biologically active in any of the assays tested and could not compete with wild-type HGFL in cell scattering experiments. These data, in addition to direct enzyme-linked immunosorbent assay analyses, suggest that the light chain may play an important role in the interaction of HGFL with its receptor, Ron. Elimination of the proposed protease cleavage site between the heavy and light chains (by mutation of Arg-483 to Glu) produced a protein with activity comparable to wild-type HGFL. Further studies with this mutated protein uncovered an additional proteolytic cleavage site that produces biologically active protein. Deletion of the various kringle domains or the amino-terminal hairpin loop had various effects in the multiple assays. These data suggest that the heavy chain may play a pivotal role in determining the functional aspects of HGFL. PMID- 9374548 TI - Defective endothelium-dependent relaxation of vascular smooth muscle and endothelial cell Ca2+ signaling in mice lacking sarco(endo)plasmic reticulum Ca2+ ATPase isoform 3. AB - Sarco(endo)plasmic reticulum Ca2+ ATPase isoform 3 (SERCA3) is one of two Ca2+ pumps serving intracellular Ca2+ signaling pools in non-muscle tissues; however, unlike the ubiquitous SERCA2b, it exhibits a restricted cell-type distribution. Gene targeting was used to generate a mouse with a null mutation in the SERCA3 gene. Homozygous mutant mice were viable, fertile, and did not exhibit an overt disease phenotype. Because SERCA3 is expressed in arterial endothelial cells, aortic ring preparations were analyzed to determine whether it is involved in the regulation of vascular tone. Contraction-isometric force relations in response to phenylephrine or KCl, as well as relaxation produced by exposure to a nitric oxide donor, were similar in wild-type and null mutant aortas. Acetylcholine induced endothelium-dependent relaxation of aortas after precontraction with phenylephrine was significantly reduced in homozygous mutants (61.3 +/- 5.6% in wild type, 35.4 +/- 7.3% in mutants). Ca2+ imaging of cultured aortic endothelial cells demonstrated that the acetylcholine-induced intracellular Ca2+ signal is sharply diminished in SERCA3-deficient cells and also indicated that replenishment of the acetylcholine-responsive Ca2+ stores is severely impaired. These results indicate that SERCA3 plays a critical role in endothelial cell Ca2+ signaling events involved in nitric oxide-mediated relaxation of vascular smooth muscle. PMID- 9374549 TI - Hyperleptinemia of pregnancy associated with the appearance of a circulating form of the leptin receptor. AB - Leptin is a hormone produced in adipose cells that regulates energy expenditure, food intake, and adiposity. In mice, we observed that circulating leptin levels increase 20-40-fold during pregnancy. Pregnant ob/ob females had no detectable serum leptin, demonstrating that the heterozygous conceptus was not the source of the leptin. However, leptin RNA and protein levels in maternal adipose tissue were not elevated. The circulating leptin was in a high molecular weight complex, suggesting that the rise in leptin was due to expression of a binding protein. Indeed, quantitative assays of serum leptin binding capacity revealed a 40-fold increase, coincident with the rise in serum leptin. Leptin binding activity reached a capacity of 207 +/- 15 nmol/liter of serum at day 18 of gestation, and half-maximal binding was observed with approximately 3 nM leptin. The binding protein was purified and partially sequenced, revealing sequence identity to the extracellular domain of the leptin receptor. We found that the placenta produces large amounts of the OB-Re isoform of leptin receptor mRNA, which encodes a soluble binding protein. Thus, the extreme hyperleptinemia of late pregnancy is attributable to binding of the leptin by a secreted form of the leptin receptor made by the placenta. PMID- 9374550 TI - Topology of NAT2, a prototypical example of a new family of amino acid transporters. AB - Amino acids are the predominant form of nitrogen available to the heterotrophic tissues of plants. These essential organic nutrients are transported across the plasma membrane of plant cells by proton-amino acid symporters. Our lab has cloned an amino acid transporter from Arabidopsis, NAT2/AAP1, that represents the first example of a new class of membrane transporters. We are investigating the structure and function of this porter because it is a member of a large gene family in plants and because its wide expression pattern suggests it plays a central role in resource allocation. In the results reported here, we investigated the topology of NAT2 by engineering a c-myc epitope on either the N or C terminus of the protein. We then used in vitro translation, partial digestion with proteinase K, and immunoprecipitation to identify a group of oriented peptide fragments. We modeled the topology of NAT2 based on the lengths of the peptide fragments that allowed us to estimate the location of protease accessible cleavage sites. We independently identified the location of the N and C termini using immunofluorescence microscopy of NAT2 expressed in COS-1 cells. We also investigated the glycosylation status of several sites of potential N linked glycosylation. Based on the combined data, we propose a novel 11 transmembrane domain model with the N terminus in the cytoplasm and C terminus facing outside the cell. This model of protein topology anchors our complementary investigations of porter structure and function using site-directed and random mutagenesis. PMID- 9374551 TI - Molecular variation of the human angiotensinogen core promoter element located between the TATA box and transcription initiation site affects its transcriptional activity. AB - Recent genetic studies indicate that several molecular variants discovered in angiotensinogen (AG), the precursor of vasoactive octapeptide angiotensin II, could potentially be responsible for inherited predisposition to human blood pressure variation. We have previously shown that a ubiquitously expressed nuclear factor, AGCF1, bound to AGCE1 (AG core promoter element 1 including the core nucleotides, CTCGTG, CTC-type) located between the TATA box and transcription initiation site (positions -25 to -1) is an authentic regulator of human AG transcription. In the present study, we showed that AGCF1 has biologically and immunologically similar properties to those of a helix-loop helix nuclear factor USF1 and examined the effects of two other naturally occurring molecular variants (ATCGTG, ATC-type and ATTGTG, ATT-type) found in the AGCE1 position on the human AG transcriptional activity. Competitive gel-shift and transfection experiments demonstrated that the transcriptional activity for the CTC- and ATC-type promoters was 2.5 times higher than that for the ATT-type through the alteration of AGCF1-binding affinity. These results suggest the possible involvement of USF1 as a component in AGCF1 formation and the potential importance of AGCE1 variation in blood pressure regulation through human AG expression. PMID- 9374552 TI - Cystic fibrosis phenotype associated with pancreatic insufficiency does not always reflect the cAMP-dependent chloride conductive pathway defect. Analysis of C225R-CFTR and R1066C-CFTR. AB - We have previously screened the cystic fibrosis transmembrane conductance regulator (CFTR) gene and identified new disease-causing mutations. C225R and R1066C are both associated with pancreatic insufficiency, but the former mutation is associated with mild and unusual lung disease, whereas the latter is associated with severe lung disease. In the present study, we expressed these mutants heterologously in HeLa cells, and we analyzed protein synthesis by immunoprecipitation and chloride channel function by using a halide-sensitive fluorescent dye, 6-methoxy-N-ethylquinolinium. Immunoprecipitation and functional studies showed that cells transfected with C225R-CFTR exhibit cAMP-dependent chloride fluxes; C225R-CFTR protein is poorly expressed but fully glycosylated and can be compared with R117H-CFTR. R1066C-CFTR protein is not correctly processed and, unlike DeltaF508-CFTR, this defect cannot be corrected by reduced temperature or overexpression in butyrate-treated cells; defective processing may occur at a different step in the biosynthetic pathway. These results point to two different mechanisms underlying the same pancreatic status and suggest that it is unwise to use pancreatic sufficiency and insufficiency to define mild and severe cystic fibrosis (CF) disease, respectively. Finally, the experimental model described here may be helpful to predict the pulmonary status of CF patients bearing mutations located in putative membrane-spanning domains of the CFTR protein. PMID- 9374553 TI - Intracellular K+ suppresses the activation of apoptosis in lymphocytes. AB - Little is known about the mechanisms of suppression of apoptosis. We have addressed the novel possibility that the level of intracellular K+ regulates the apoptotic process by controlling the activity of death enzymes. We show that K+, at normal intracellular levels, inhibits both apoptotic DNA fragmentation and caspase-3(CPP32)-like protease activation, suggesting that intracellular K+ loss must occur early during apoptosis. Direct measurement of K+ by inductively coupled plasma/mass spectrometry and flow cytometry indicates a major decrease in intracellular K+ concentration in the apoptotic cell. Flow cytometric analysis revealed that caspase and nuclease activity were restricted to the subpopulation of cells with reduced K+. Disruption of the natural K+ electrochemical gradient suppressed the activity of both caspase and nuclease independent of the mode of activation of the apoptotic inducing agent, demonstrating that a decrease in intracellular K+ concentration is a necessary, early event in programmed cell death. PMID- 9374554 TI - Biochemical characterization of mapmodulin, a protein that binds microtubule associated proteins. AB - Mapmodulin is a 31-kDa protein that stimulates the microtubule- and dynein dependent localization of Golgi complexes in semi-intact Chinese hamster ovary cells. We have shown previously that it binds the microtubule binding domains of the microtubule-associated proteins, MAP2, MAP4, and tau. We also showed that mapmodulin is identical to a protein named PHAPI (Vaesen, M., Barnikol-Watanabe, S. , Gotz, H., Awni, L.A., Cole, T., Zimmermann, B., Kratzin, H.D. and Hilschmann, N. (1994) Biol. Chem. Hoppe-Seyler 375, 113-126). We report here that mapmodulin is a phosphoprotein that is predominantly cytosolic but is also found peripherally associated with endoplasmic reticulum and Golgi membranes in mammalian cells. The protein occurs as a trimer in cytosol, and phosphorylation is required for its microtubule-associated protein-binding activity. Heat treatment of nonphosphorylated mapmodulin can render it competent for binding to microtubule-associated proteins, suggesting that phosphorylation induces a conformational change in mapmodulin. Finally, despite identity in polypeptide sequence with a protein reported to act as an inhibitor of protein phosphatase 2A, native mapmodulin was not able to inhibit protein phosphatase 2A in Chinese hamster ovary cell cytosol. PMID- 9374555 TI - Identification of a placental enhancer for the human leptin gene. AB - Leptin is a hormone that regulates metabolic efficiency, energy expenditure, and food intake. Leptin is produced chiefly in adipose cells, but in humans, mRNA encoding leptin is also present in the placenta. Here we elucidate the basis for placental leptin production. The same promoter is used for adipose and placental transcription. An upstream enhancer functions in the JEG-3 and JAR choriocarcinoma cell lines but not in adipocytes or HeLa cells. The minimal positive acting region is 60 base pairs in length. This region is within a MER11 repetitive element, suggesting that human placental expression of leptin is the result of insertion of this element. Binding analyses demonstrated three protein binding sites, designated placental leptin enhancer elements (PLE)1, PLE2, and PLE3. PLE2 binds Sp1. Enhancer activity was reduced by mutation of the PLE1 or PLE3 sites but was unaffected by alteration of PLE2. Proteins binding to PLE3 were present in JEG-3 and human placental nuclear extracts but not in extracts from non-placental sources. Upon triplication, the PLE3 element was a strong enhancer in choriocarcinoma cells but not in HeLa cells. The protein binding to the PLE3 motif appears to be a novel, placenta-specific transcription factor. PMID- 9374556 TI - Annual summary of vital statistics--1996. AB - Several recent trends in the vital statistics of the United States continued in 1996, including an increase in life expectancy and declines in infant mortality, births to teenage mothers, age-adjusted death rates, and death rates for children and adolescents. In 1996, there were an estimated 3 914 953 births in the United States. The preliminary birth rate remained unchanged at 14.8 births per 1000 population, and the fertility rate, births per 1000 women 15 to 44 years of age, was essentially the same at 65.7. Fertility rates rose slightly for most racial and ethnic groups except black women, for whom the rate hit a historic low of 70.8. Overall, fertility remains particularly high for Hispanic women, although there is considerable variation within this heterogenous group. For the fifth consecutive year, birth rates dropped for teenagers. Birth rates for women >/=30 years of age continued to increase. The birth rate for unmarried women declined 1% in 1996 to 44.6 births per 1000 unmarried women, continuing the decline noted in 1995 for the first time in 2 decades. The percentage of women who began prenatal care in the first trimester rose in 1996 to 81.8%, whereas the percentage with late (third trimester) or no care dropped to 4.1%. The rise in timely prenatal care was greatest for black and Hispanic women. The percentage of low birth weight (LBW) infants reached 7.4% in 1996, its highest level since 1975. The very low birth weight rate remained unchanged at 1.4%. The rise in LBW occurred primarily among white women, whereas the LBW rate for black women dropped to 13.0%, the lowest rate reported since 1987. The rise among white women is only partially a result of increases in multiple births, because LBW rates have also risen among white singleton births. The multiple birth ratio rose again in 1996 by 2%, as it has since 1980. The rise was particularly large for higher order multiple births. Infant mortality reached an all time low level of 7.2 deaths per 1000 births, based on preliminary 1996 data. Neonatal and postneonatal rates declined, as did rates for both black and white infants. National birth weight specific mortality rates are reported here for the first time. In 1995, 63% of infant deaths occurred to the 7.3% of the population that was born LBW. The four leading cause of infant death were congenital anomalies, disorders relating to short gestation and unspecified birth weight, sudden infant death syndrome, and respiratory distress syndrome, accounting for more than half of infant deaths in 1996. Despite the declines in infant mortality, the United States continues to rank poorly in international comparisons of infant mortality. Expectation of life at birth reached a new high in 1996 of 76.1 years for all gender and race groups combined. Age-adjusted mortality rates declined in 1996 for diseases of the heart, malignant neoplasms, cerebrovascular diseases, accidents and adverse effects, chronic liver disease and cirrhosis, and suicide. They rose, as in the past several years, for chronic obstructive pulmonary diseases, diabetes mellitus, and pneumonia and influenza. For the first time since human immunodeficiency virus infection was created as a special cause-of death category in 1987, death rates for human immunodeficiency virus infection declined from 15.6 in 1995 to 11.6 in 1996. The homicide rate also declined, as it has since 1991. Death rates for children between 1 and 19 years of age declined in 1996, with an estimated 29 183 deaths to children. Unintentional injury mortality has dropped by approximately 50% among children and adolescents since 1979, although it remains the leading cause of death for all age groups of children from 1 to 19 years. Homicide was the fourth leading cause of death for children 1 to 4 and 5 to 9 years of age, the third leading cause for children 10 to 14, and the second leading cause for 15 to 19 year olds. PMID- 9374557 TI - Screening dipstick urinalysis: a time to change. AB - OBJECTIVE: This study attempted to determine the minimal cost of screening dipstick urinalyses in a hypothetical cohort of 2000 asymptomatic pediatric patients in a primary care setting. METHODOLOGY: The minimal cost utilizing a private practitioner in an urban or suburban group pediatric setting was calculated. Costs were determined by using current charges for supplies ordered to perform tests in the office, charges for tests performed by a commercial laboratory, and the cost of an initial evaluation by a pediatric nephrologist. Data from published studies were also utilized. RESULTS: Nine percent (179/2000) of patients were calculated to have an initial abnormal urinalysis. Upon retesting only 1.5% (29/2000) of patients were calculated to have a persistent abnormality. The calculated rate of a false positive/transient abnormality for all patients in the hypothetical cohort of 2000 asymptomatic pediatric patients was 84% (150/179). The calculated minimal cost for the outpatient evaluation of 2000 asymptomatic pediatric patients by dipstick urinalyses ranged between $5022 to $6475. The range depends on whether 50% versus 100% of patients with a repeat abnormal dipstick urinalysis were referred to a pediatric nephrologist for further evaluation. The calculated cost was $1290 to initially screen all 2000 patients with a dipstick urinalysis or 65 cents per patient. The calculated cost to evaluate the 29 patients with any persistent abnormality on repeat dipstick urinalysis was $3732 to $5185 or $129 to $179 per patient. This is the calculated cost for a single screening of 2000 asymptomatic pediatric patients. The calculated cost for four multiple screening urinalyses as currently recommended is $20 088 to $25 900. Additionally, these are only minimal initial calculated costs. Costs of any renal imagining or function studies ordered by the pediatric nephrologist or the pediatrician pursuing a further evaluation on his/her own were not included. CONCLUSION: Multiple screening dipstick urinalyses in asymptomatic pediatric patients are costly and should be discontinued. In their place, we propose that a single screening dipstick urinalysis be obtained at school entry age, between 5 and 6 years old, in all asymptomatic children. The sample should be a first morning void. PMID- 9374558 TI - Factors affecting the decision to seek health care: the voice of adolescents. AB - OBJECTIVE: To learn from teenagers why they do, or do not, seek preventive health care. METHODS: A teen-centered methodology utilized focus groups, nominal group technique sessions, and surveys to allow adolescents to generate, prioritize, and explain their own responses. This article reports the qualitative explanations offered by youths in focus groups. In 21 groups, teenagers commented on the 15 factors that ninth graders in the School District of Philadelphia had determined most influenced their decision to seek care. Transcriptions were reviewed for consistent themes. Direct quotations are presented here to be representative of those themes. RESULTS: Two key points emerged. First, adolescents are more concerned about provider characteristics than site or system characteristics. Second, they worry deeply about disease transmission in the health care setting. Teenagers suggest some simple steps that may produce significant inroads toward developing an effective working relationship with them. A few examples include: to alleviate anxiety of disease transmission, providers should wash hands and remove instruments from sterile packaging in front of patients; to reassure teenagers of competence, providers should keep diplomas and certificates displayed; and to alleviate perceptions of racism, sites should post signs that clearly explain why patients are sometimes seen out of order. CONCLUSIONS: Adolescents know what draws them to services and what offends them. This study documents, in the words of youths, the factors contributing to their decisions to seek care. The results allow health professionals who care for adolescents to consider what they do well and where change may be needed. PMID- 9374559 TI - Knowledge and attitudes about otitis media risk: implications for prevention. AB - OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for =2 months. Women were more knowledgeable about OM signs and symptoms than about risk factors. Mean OM knowledge score (the sum of correct true-false responses) was 7.0 (standard deviation = 1.6). Using multiple linear regression, knowledge score was significantly related to marital status, education, age, area of residence, breastfeeding (months), and number of cigarettes smoked per day by the mother, but not to infant or sibling OM history or day care attendance (R = .23). Infant history of OM (odds ratio, 1.9; 95% confidence interval, 1.1 to 3.2) and white race (odds ratio, 0.3; 95% confidence interval, 0. 1 to 0.8), but not the presence of risk factors, were significantly related to having received clinicians' advice about OM prevention advice. CONCLUSION: OM education and prevention programs should target pregnant women and new mothers with OM risk factors, and those who are young, single, and less educated. PMID- 9374560 TI - Respiratory syncytial virus immune globulin treatment of RSV lower respiratory tract infection in previously healthy children. AB - OBJECTIVE: To evaluate the efficacy of high titer respiratory syncytial virus (RSV) immune globulin (RSVIG) in the treatment of previously healthy children hospitalized with proven RSV lower tract infection (LRI). METHOD: Infants and young children =2 years of age with RSV LRI of =4 days duration, and respiratory scores >/=2. 5 were enrolled. RESULTS: One hundred and one previously healthy children hospitalized with RSV LRI received either 1500 mg/kg of RSVIG (RespiGam, MedImmune Inc, Gaithersburg, MD) or albumin placebo in a randomized, double-blind, placebo-controlled trial. Forty-six RSVIG and 52 recipients of placebo met all eligibility criteria. Demographic characteristics of the two groups were similar. More RSVIG recipients (46% vs 29%) had an SaO2 =85% at entry than did placebo recipients, but a higher proportion of placebo recipients required intensive care unit (ICU) care and mechanical ventilation at study entry. The mean RSV hospital stay was 5.52 +/- 0.69 days (SE) for placebo and 4.58 +/- 0.40 days for RSVIG. Additionally, there was an interaction between treatment group and entry respiratory score, which led to subgroup analysis. Children with modest respiratory illness did not receive any benefit from RSVIG therapy. RSVIG recipients with more severe illness (entry respiratory scores >/=3.0) had 1.6 fewer hospital days and 2.7 days less ICU stays. CONCLUSION: RSVIG infusions seemed safe and generally well tolerated. Although some beneficial effect trends were seen for those with more severe disease who were treated there was no evidence that treatment with RSVIG resulted in reduced hospitalization and reduced ICU stays in all children with RSV disease. PMID- 9374561 TI - Nosocomial respiratory syncytial virus infection in Canadian pediatric hospitals: a Pediatric Investigators Collaborative Network on Infections in Canada Study. AB - OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality. PMID- 9374562 TI - Children's health care use in the Healthy Kids Program. AB - BACKGROUND: In 1990, the Florida Legislature established the Florida Healthy Kids Corporation to implement the concept of school enrollment-based health insurance coverage for children. The county school districts are used as a grouping mechanism to negotiate health insurance policies. The Florida Healthy Kids Corporation negotiates contracts with health maintenance organizations (HMOs) to assume financial risk and to provide health care services at each program site. In 1994, there were five sites with four different participating HMOs. Assessing quality of care is particularly important when contracting with HMOs because of the perception that financial and utilization review arrangements may restrict the enrollees' access to needed health care. One essential component of health care quality is the extent to which health care services are used in a manner consistent with the expected pattern of use for the population of enrolled children. The purpose of this study is to compare children's health care use across five different Florida Healthy Kids Program sites. Specifically, we compare the enrollees' actual health care use across HMO settings and program sites to the expected health care use based on the enrollees' case-mix. METHODS: Each HMO provided child-specific health care use data including Physician's Current Procedural Terminology codes and International Classification of Diseases, 9th Revision codes. We used the Ambulatory Care Groups (ACGs) software to compare the children's actual health care use to the expected health care use at each site adjusted for case-mix. Several steps were then taken to determine if the children were receiving the anticipated number of health care visits based on their diagnoses. First, we divided the average number of encounters at each site by the group average across all of the sites, without adjusting for the case-mix of the enrollees. We then divided the average number of visits at each site by the expected number of visits based on the case-mix adjustment. A value of 1.00 means that the actual use and the expected use are identical. Values below 1 indicate underuse and values over 1 indicate overuse of health care services. Statistical comparisons of the actual versus expected average health care use across the five sites were performed by deriving the appropriate chi2 statistics. RESULTS: A census of all children (N = 14 688) enrolled in the Florida Healthy Kids Program at each of the sites for 6 months or longer were included in the analysis. The average number of health care encounters across all sites for a 12 month time period was 2.98 +/- 4.6 visits. After adjusting for the case-mix of the enrollees in each site using the ACG software, several of the five sites differed from one in a statistically significant way. However, these statistical assessments must be tempered with assessing the practical magnitude of the observed differences. CONCLUSIONS: The number of public and private efforts to insure children who are not eligible for Medicaid and whose parents cannot purchase private insurance has grown dramatically. These programs are vital for ensuring financial access to care for uninsured children. However, it is essential that such programs are not viewed as merely cost containment efforts. Assessing the degree to which children receive the health care services they need across multiple delivery settings is an essential yet challenging component of quality assurance. Generally, our analysis indicates that children in the Florida Healthy Kids Program are receiving the amount of health care expected based on their health care needs; which is one component of a high-quality health care program. PMID- 9374563 TI - Renal function after short-term ibuprofen use in infants and children. AB - OBJECTIVE: To test the hypothesis that short-term use of ibuprofen increases the risk of impaired renal function in children. STUDY DESIGN: Randomized, double blind acetaminophen-controlled clinical trial. Children with a febrile illness were enrolled from outpatient pediatric and family medicine practices and randomly assigned to receive either acetaminophen suspension or one of two dosages of ibuprofen suspension (5 mg/kg or 10 mg/kg) for fever control. RESULTS: Mean blood urea nitrogen levels on admission among children admitted to hospital and assigned ibuprofen 5 mg/kg (n = 96), ibuprofen 10 mg/kg (n = 102), and acetaminophen 12 mg/kg (n = 87) were 4.1, 3.8, and 3.9 mmol/L, respectively. The corresponding creatinine levels were 43, 41, and 43 micromol/L, respectively. The prevalence of a creatinine level >62 micromol/L was 9.5% overall and did not vary by antipyretic assignment. Among 83 children hospitalized with dehydration, the mean creatinine level was 44 micromol/L, and the prevalence of an elevated creatinine was 14%; neither measure varied by antipyretic assignment. CONCLUSION: Although renal failure in children has been reported after ibuprofen use, these data suggest that for short-term use the risk of less severe renal impairment, as reflected by blood urea nitrogen and creatinine levels, is small and not significantly greater than that after acetaminophen use. PMID- 9374564 TI - Predictors of posttraumatic stress symptoms in childhood cancer survivors. AB - OBJECTIVE: The diagnosis and treatment of childhood cancer are extremely stressful experiences, with psychological sequelae which can persist many years after the end of treatment. This study investigated the relative contributions of general anxiety, treatment intensity, medical sequelae of treatment, and the subjective appraisal of life threat and treatment intensity to later posttraumatic stress symptoms, such as intrusive memories, avoidance, and hypervigilance. METHOD: One hundred eighty-six childhood cancer survivors ages 8 through 20 years, off of treatment for more than 1 year, and their parents completed questionnaires. Medical sequelae of treatment and intensity of treatment were rated by a pediatric oncologist. RESULTS: Significant, independent predictors of persistent posttraumatic stress symptoms included: 1) the survivor's retrospective subjective appraisal of life threat at the time of treatment, and the degree to which the survivor experienced the treatment as "hard" or "scary"; 2) the child's general level of anxiety; 3) history of other stressful experiences; 4) time since the termination of treatment (negative association); 5) female gender; and 6) family and social support. Mother's perception of treatment and life threat contributed to anxiety and subjective appraisal for the survivor, but did not independently contribute to posttraumatic stress symptoms. CONCLUSIONS: Symptoms of posttraumatic stress seem to decrease with time, but are persistent in a subset of childhood cancer survivors. Other than time and gender, the predictors of posttraumatic stress symptoms are primarily subjective factors (ie, anxiety and subjective appraisal) rather than objective stressors of treatment and medical sequelae. PMID- 9374565 TI - Subcutaneous granuloma annulare: a review of 47 cases. AB - OBJECTIVE: The purpose of this study was to review and provide information regarding characteristic findings, diagnostic work-up, course, and treatment associated with subcutaneous granuloma annulare (SGA). MATERIALS AND METHODS: The medical and surgical records of 47 patients with SGA, who were diagnosed and treated at our institution over the past 26 years, were reviewed. RESULTS: All patients presented with a painless soft tissue nodule(s) of the extremities or scalp. The mean age at presentation was 4.3 years, with 19% of the patients encountering one or more recurrences. The mean time of recurrence was 10 months. Definitive diagnosis in all patients was made by biopsy, and no patient progressed to any recognized systemic illness or connective tissue disorder. CONCLUSIONS: SGA is a benign inflammatory skin lesion that should be considered in the differential diagnosis of a subcutaneous nodule(s) of the scalp and/or distal extremities of an otherwise healthy child. Because the nodule(s) are benign and may recur with or without surgical biopsy, reassurance is the best management. PMID- 9374566 TI - Effectiveness of postprandial Humalog in toddlers with diabetes. AB - OBJECTIVE: The purpose of this study was to determine whether postprandial administration of the new rapid-acting insulin analog Humalog could effectively reduce glucose excursions in children <5 years old. DESIGN: Human Regular insulin given before a meal was compared with the same dose of Humalog after a meal of equal carbohydrate content in five toddlers with insulin-dependent (type 1) diabetes mellitus. In addition, the use of Humalog before a meal was compared with Humalog given after a meal of equal carbohydrate content in five other toddlers. The dose of long-acting insulin was not changed during the study period. Blood glucose levels were determined at fasting and at 1, 2, and 4 hours postprandially. RESULTS: The 2-hour glucose excursions were significantly lower when postprandial Humalog administration was compared with preprandial Human Regular insulin administration. In contrast, glucose excursions were similar when Humalog was taken before or after the meal. CONCLUSION: These data show that it is efficacious to give Humalog insulin postprandially in toddlers with type 1 diabetes, allowing increased safety for the young child. The insulin dose can be both matched to the actual food intake and timed to give families increased flexibility and control at mealtime. PMID- 9374567 TI - Twenty-four-hour profile of growth hormone in cyclic nocturnal total parenteral nutrition. AB - OBJECTIVE: To detect the effect of the loss of alimentation rhythmicity on a circadian rhythm of human growth hormone (HGH) secretion, a 24-hour profile of HGH was studied in a growing child on cyclic nocturnal total parenteral nutrition (TPN). Twenty-four-hour profiles of substrates and metabolic hormones were also studied to evaluate the efficiency of cyclic nocturnal TPN on childhood growth. STUDY DESIGN: Periodic blood samples from a child with megacystis-microcolon intestinal-hypoperistalsis syndrome were obtained on five occasions, at ages 6, 7, 8, 9, and 11, when she was on cyclic nocturnal TPN. RESULTS: Peak HGH secretion appeared with the onset of deep sleep despite the concomitant hyperglycemia and hyperinsulinemia induced by TPN at night. Smaller peaks of HGH were also observed during the noninfusion period during the day. Twenty-four-hour profiles of substrates and metabolic hormones indicated a switch from glucose use during the infusion phase to an oxidation of lipids during the noninfusion period. CONCLUSION: The fact that the patient's growth curve remains within normal limits suggests that cyclic nocturnal TPN would be an efficient method of nutritional support. During cyclic nocturnal TPN, regular rhythm of HGH secretion occurs, and normal childhood growth is achieved. PMID- 9374568 TI - Effective prophylactic therapy for cyclic vomiting syndrome in children using amitriptyline or cyproheptadine. AB - OBJECTIVE: To evaluate our experience using the antimigraine prophylactic drugs, amitriptyline and cyproheptadine, for the prophylactic management of cyclic vomiting syndrome (CVS) in children. METHODS AND PATIENTS: Twenty-seven patients (16 males) ranging in age from 2 to 16 years at diagnosis, fulfilling the diagnostic criteria for CVS and treated prophylactically with either amitriptyline (22) or/and cyproheptadine (6) were identified through retrospective chart review. Individual patient data were corroborated by the attending physician and/or interviews with patients and families. Minimum follow up time before entry into the study group was 5 months. Patients were stratified according to three treatment outcomes: 1) complete response-no attacks, 2) partial response-50% or greater reduction in frequency of attacks, and 3) no response-less than 50% decrease in frequency of attacks. RESULTS: Of the 22 patients treated with amitriptyline, 16 (73%) had a complete response while 4 (18%) had a partial response. Of the 6 patients treated with cyproheptadine, 4 (66%) had a complete response and 1 (17%) had a partial response. Thus, 91% of the amitriptyline group and 83% of the cyproheptadine group had at least a partial response to therapy. No patients experienced significant side effects to either medication. CONCLUSION: The antimigraine prophylactic drugs, amitriptyline and cyproheptadine, represent effective prophylactic agents for the management of CVS in the vast majority of patients fulfilling the diagnostic criteria for this syndrome. PMID- 9374569 TI - Survival and developmental disability in infants with birth weights of 501 to 800 grams, born between 1979 and 1994. AB - OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17 county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age. PMID- 9374571 TI - Discontinuation of methotrexate treatment in juvenile rheumatoid arthritis. AB - OBJECTIVE: Children with juvenile rheumatoid arthritis (JRA) treated with methotrexate (MTX) were examined for their course after the discontinuation of the drug to define the relapse and remission rates and to identify predictors of relapse. METHODOLOGY: A retrospective chart review of all patients with JRA was conducted in two pediatric rheumatology centers. A total of 101 patients being treated with MTX were identified. Dose, response to the drug, and length of time until reaching a state of complete control were noted. The outcome of patients with a complete response in whom the drug was discontinued was examined with regards to length of time to relapse or continued remission. RESULTS: In 25 patients, MTX was discontinued after reaching complete control of the disease. There were no statistically significant predictors of response to MTX identified. Of 25 whose MTX was discontinued, relapse occurred in 13 (52%) after a mean of 11 months after discontinuation. There was no significant difference among patients who relapsed or those who remained in remission as to sex, subtype of JRA, number of months to complete control, or number of months in complete control until discontinuing MTX. Patients younger than 41/2 years at diagnosis were found to be more likely to relapse than patients diagnosed at a later age. In 10 of the patients who relapsed, complete control was induced within a mean of 7 months after restarting MTX. CONCLUSION: The optimal time for discontinuing MTX in children with JRA who have achieved complete control is unknown. Relapse occurred in approximately half of the patients in whom MTX was discontinued. Because response to reinstitution of the drug is good, it is reasonable to discontinue MTX after prolonged complete control. It remains to be seen whether the relapse rate can be improved by waiting for longer periods of time in complete control before its discontinuation. PMID- 9374570 TI - A longitudinal study of developmental outcome of infants with bronchopulmonary dysplasia and very low birth weight. AB - OBJECTIVE: Bronchopulmonary dysplasia (BPD) is now the leading cause of lung disease in US infants. In a large regional cohort, we tested the hypothesis that despite innovations in neonatal care, very low birth weight (VLBW) infants (<1500 g) with BPD had poorer developmental outcomes than nonaffected infants during the first 3 years of life, and that BPD predicted poorer outcome beyond the effects of other risk factors. METHODS: Three groups of infants (122 with BPD, 84 VLBW without BPD, and 123 full-term) were followed longitudinally to 3 years of age with the Bayley Scales of Mental and Motor Development. Comparison groups of VLBW infants without BPD and full-term infants did not differ in sex, race, or socioeconomic status. Statistical analyses included hierarchical and stepwise multiple regression. RESULTS: Infants with BPD performed more poorly at all ages. By 3 years, cognitive and/or motor development was in the range of retardation (<70 standard score) for 21% to 22% of infants with BPD. In multiple regression analyses controlling for socioeconomic and neonatal risk conditions, BPD had an independent negative effect on motor outcome at 3 years. Neurologic risk, a summary measure of neurologic problems other than intraventricular hemorrhage, and the presence of BPD independently predicted motor delay. By 3 years, social class, race, and neurologic risk predicted mental outcome, suggesting that the specific effects of BPD are primarily on the motor domain. CONCLUSIONS: In VLBW infants, BPD predicts poorer motor outcome at 3 years, after control for other risks. Cohorts of infants with BPD also had higher rates of mental retardation, associated with greater neurologic and social risk. These findings underscore the need for intensive prevention and habilitation efforts for this growing group of VLBW survivors, as well as investigation into the potential role of BPD in the higher rates of learning disabilities in VLBW cohorts at school age. PMID- 9374572 TI - Exudative lung injury is associated with decreased levels of surfactant proteins in a rat model of meconium aspiration. AB - OBJECTIVE: Meconium aspiration syndrome remains a common cause of respiratory failure in neonates. The acute effects of meconium aspiration are inactivation of lung surfactant in vivo and in vitro. This study investigated the delayed effects of meconium on alveolar surfactant phospholipids and protein levels in spontaneously breathing animals. METHODS: Twenty-two adult rats were given 4.3 mg of dry weight human meconium after endotracheal intubation. Rats were briefly mechanically ventilated in room air, extubated, then killed after 16 (n = 6), 24 (n = 6), 48 (n = 6), and 72 hours (n = 4). Control animals received the same volume of normal saline (n = 7) or no meconium (n = 7). Bronchoalveolar lavage and tissue specimens were evaluated for inflammatory cells, total proteins, surfactant phospholipids, and surfactant proteins. RESULTS: Meconium caused exudative lung injury that was reflected in increased cell counts and proteins in alveolar lavage fluid. The peak injury occurred at 16 hours after instillation, whereas recovery occurred by 72 hours. Although total lavage fluid phospholipids did not change over time, phospholipid and dipalmitoyl phosphatidylcholine in large aggregates tended to decrease at 24 hours. Western blot analysis demonstrated time-dependent qualitative decreases in surfactant proteins A and B (SP-A, SP-B) in meconium-instilled animals compared with the controls. ELISA for SP-B confirmed the Western blot findings with total SP-B in large aggregate decreasing from 25 +/- 4 microg in controls to 6.6 +/- 0.8 microg at 24 hours of injury. CONCLUSIONS: Our study suggests that the exudative lung injury with meconium instillation is associated with decreased levels of SP-A and SP-B in the large aggregate fraction of lung surfactant. We speculate that decreased secretion and/or increased degradation accounts for lower levels of SP-B in bronchoalveolar lavage fluid. PMID- 9374573 TI - Interventions for perinatal hypoxic-ischemic encephalopathy. PMID- 9374574 TI - Fourth edition of the Guidelines for Perinatal Care: summary of changes. PMID- 9374575 TI - Hypothermia treatment and the newborn. PMID- 9374576 TI - Neuroprotection and perinatal brain care: the field of the future, currently going nowhere!? PMID- 9374577 TI - The routine urinalysis: to keep or not to keep; that is the question. PMID- 9374578 TI - Depressed skull fracture in a 7-month-old who fell from bed. PMID- 9374580 TI - Breastfeeding and the risk of life-threatening enterotoxigenic Escherichia coli diarrhea in Bangladeshi infants and children. AB - OBJECTIVE: To assess the relationship between breastfeeding and the risk of life threatening enterotoxigenic Escherichia coli (ETEC) diarrhea among Bangladeshi infants and young children <36 months of age. DESIGN: Case-control study. SETTING: A rural Bangladesh community. PARTICIPANTS: A total of 168 cases with clinically severe ETEC diarrhea detected in a treatment center-based surveillance system during 1985 to 1986 and 3679 controls selected in three surveys of the same community during the same calendar interval. OUTCOMES: Cases and controls were compared for the frequency of antecedent breastfeeding patterns. RESULTS: Compared with other feeding modes, exclusive breastfeeding of infants was associated with significant protection against severe ETEC diarrhea (relative risk [RR] = 0.51; 95% confidence interval [CI]: 0.28,0.96). However, during the second and third years of life, the risk of this outcome was similar in both breastfed and nonbreastfed children (RR = 0.98; 95% CI: 0.45,2.12), and no significant overall protective association between breastfeeding and severe ETEC diarrhea was evident during the first 3 years of life (RR = 0.86; 95% CI: 0.43,1. 74). CONCLUSIONS: Exclusive breastfeeding appeared to protect infants against severe ETEC diarrhea, but breastfeeding was not associated with protection after infancy, nor was it associated with a major overall reduction of severe ETEC disease during the first 3 years of life. Although not diminishing the importance of breastfeeding, our findings suggest that other interventions, such as immunization and education about proper food hygiene, may also be required in efforts to prevent this major pediatric disease. PMID- 9374582 TI - Hyponatremic seizures secondary to oral water intoxication in infancy: association with commercial bottled drinking water. AB - In recent years, hyponatremic seizures resulting from water intoxication have been reported in the United States with an increasing frequency that some have likened to an epidemic. Infants of parents living in poverty and uninformed of the risks of feeding fluids other than infant formula to their babies are particularly at risk. Young infants with vomiting and diarrhea are especially prone to developing hyponatremia if fed fluids lacking sufficient sodium, but even those who are otherwise well may develop symptomatic hyponatremia as a result of being fed excess solute-free water. Most often tap water, either in the form of supplemental feedings or overly dilute formula, has been given in excessive amounts over relatively short periods of time. Less frequently, water in other forms such as juice, soda, or tea has been implicated. This report includes the cases of two infants treated at our institution for hyponatremic seizures and water intoxication after being fed with the same bottled drinking water product marketed for use in infants. The medical records of all infants =1 year of age admitted to our institution over 10 years with the diagnosis of hyponatremic seizures were also reviewed. PMID- 9374583 TI - Vapocoolant spray is equally effective as EMLA cream in reducing immunization pain in school-aged children. AB - BACKGROUND: Untreated immunization pain causes undue distress and contributes to underimmunization through physician, and possibly parental, resistance to multiple simultaneous injections. OBJECTIVE: To compare the efficacies of two pain management methods in reducing immediate immunization injection pain and distress in school-aged children. DESIGN: A randomized, controlled clinical trial of eutectic mixture of local anesthetics (EMLA) cream and vapocoolant spray. PATIENTS: Children aged 4 to 6 years and scheduled to receive diphtheria and tetanus toxoids and acellular pertussis vaccine (DTaP) during health supervision visits. INTERVENTIONS: Enrolled children were randomized to one of three treatment groups: 1) EMLA cream + distraction; 2) vapocoolant spray + distraction; or 3) distraction alone (control). The specific pharmacologic pain control interventions consisted of EMLA cream (2.5% lidocaine, 2.5% prilocaine [Astra Pharmaceutical Products, Inc, Westborough, MA] $15. 00/patient; applied 60 minutes before injection) and vapocoolant spray (Fluori-Methane [Gebauer Company, Cleveland, OH] $0. 50/patient; applied via spray-saturated cotton ball for 15 seconds immediately before injection). MAIN OUTCOME MEASURES: The blinded investigator (BI) measured (by edited videotape) cry duration and the number of pain behaviors using the Observational Scale of Behavioral Distress. Pain visual analog scales (linear and faces scales) were completed by the child, parent, nurse, and the BI. RESULTS: Sixty-two children, aged 4.5 +/- 0.4 years (mean +/- SD) were randomized. The three treatment groups had similar subject characteristics. All pain measures and cry duration were similar for EMLA and vapocoolant spray. Both EMLA and spray were significantly better than control. Results for spray vs control: cry duration (seconds): 8.5 +/- 21.0 vs 38.6 +/- 50.5; number of pain behaviors: 1.2 +/- 1.9 vs. 3.1 +/- 2.1; child-scored faces scale: 2.0 +/- 2.4 vs. 4.1 +/- 2.3; parent-scored faces scale: 1.6 +/- 1.6 vs. 3.0 +/- 1.7; nurse-scored faces scale: 1.6 +/- 1.2 vs. 3.1 +/- 1.4; and BI-scored faces scale: 1.0 +/- 1.5 vs. 2.4 +/- 1.4. CONCLUSIONS: When combined with distraction, vapocoolant spray significantly reduces immediate injection pain compared with distraction alone, and is equally effective as, less expensive, and faster-acting than EMLA cream. As an effective, inexpensive, and convenient pain control method, vapocoolant spray may help overcome physician and parent resistance to multiple injections that leads to missed opportunities to immunize. PMID- 9374590 TI - The flow-volume curve in patients with obstructive airway diseases partial analysis and functional importance. AB - Flow-volume curves in patients with obstructive airway disease differs from that observed in healthy subjects. Two types of pathological curves can be differentiated: these with clear sharp bend and intermediate forms characterised by the different grade of concavity of the descending segments plotted against X axis. The aim of our present investigation is to elucidate the mechanisms which determines the forced expiratory airflow course in patients with obstructive airway diseases. Patients with sharp bend curves show changes of the several lung function data which are more advanced than in subjects with the intermediate forms of the flow-volume curves. In cases of bend curves the volume of the forced expiration can be differentiated on the two parts: circumferential and serial. Circumferential volume exhaled on the very beginning of the expiration (above the bend) amounts 0.118L in average. This volume depends on the expiratory narrowing of the bronchi from the 1-st to 9-th generation. The serial volume contained between the bend and the end of expiration amounts about 95% of the expired volume. Flow limitation occurs in 5-th to 9-th generations which is manifested by the strong increase of the flow resistance. The intermediate types of the flow volume curves is caused by the inhomogenous emptying of the lung together with corresponding volume dependent narrowing of the bronchi. The same mechanisms can be detected even on the bodypletysmographic tidal breathing resistance curves. The concave and particularly bend flow-volume curves has been attributed to the pulmonary emphysema. This is not entirely truth. Other conditions leading to inhomogenic emptying of the lung due to airway and parenchymal changes (such as lung cicatrisation) can influence expiratory flow course resulting in concave or even bend flow-volume relationships. PMID- 9374591 TI - Usefulness of new DNA extraction procedure for PCR technique in species identification of Entamoeba isolates. AB - In this study we have developed a modified CLARK and DIAMOND (1992, 1993) method using the polymerase chain reaction to amplify amoebic ribosomal RNA genes that allow either specific detection of Entamoeba histolytica s. str. or amoeba species identification. DNA was isolated from cultured protozoa or from stool samples (cysts and/or trophozoites). Cultures of xenic or axenic material (also stool samples) were treated with Easy Genomic DNA Prep or Genomic DNA Prep Plus (A&A Biotechnology, Poland) for DNA isolation. With these new procedures, DNA can be obtained effectively and with high degree of purity. 13 amoeba strains were investigated. Three strains produced an 876 bp fragment with Psp5 and Psp3 primers (specific product for E. histolytica s. str). Three strains gave a specific 876 bp product for E. dispar with NPsp5 and NPsp3 primers. Two strains were E. moshkovskii as identified by KpnI digestion of PCR products obtained with RD5 and RD3 primers. Four strains (one of them was cultured in two laboratories) were E. invadens as identified by Hinfl or HhaI digestion of PCR products obtained with RD5 and RD3 primers. Characteristic RFLP patterns with these enzymes was also obtained for E. terrapinae and Blastocystis hominis. This RFLP analysis show significant promise as a medical diagnostic tool particularly useful for species identification. PMID- 9374592 TI - Estimation of distribution parameters of some avian parasites. AB - Occurrence of nematodes (mostly dominating and common species of Porrocaecum ensicaudatum and P. semiteres) in host populations of birds (Turdus merula, T. philomelos, Sturnus vulgaris and Scolopax rusticola) was summarized in frequency distributions, and tests of agreement with the Poisson model as well as the modified binomial have been computed. Comparisons of the observed frequencies with the expected ones showed the high values (3--257) of the coefficient of dispersion, the so-called "overdispersion", characteristic for the negative binomial which is an extension of the Poisson model. A nearly perfect fitness of the counted (observed) with the expected frequencies was found for S. vulgaris both in the analysis of nematode metapopulation and their common species of P. ensicaudatum. Some deviations from the expectations were found for tracing of all nematode species distributions in T. merula, T. philomelos. On the other hand, the same model (negative binomial distribution according to moment method) has fitted quite well to each for common or dominating nematode species. PMID- 9374593 TI - Resistance to the insecticides lufenuron and propoxur in natural populations of Drosophila melanogaster (Diptera: Drosophilidae). AB - Lufenuron is a newly marketed benzoylphenyl urea chitin-synthesis inhibitor insecticide that is effective against certain insects, including Drosophila melanogaster (Meigen). Resistance to this class of insecticides is not widespread in pest insect populations and, for the resistance that has been reported, the genetic basis is not understood. In previous work, natural population strains of D. melanogaster from 2 widely separated locations in the United States were found to be as much as 100 times more resistant to lufenuron when compared with laboratory strains. It was postulated that this resistance is the result of cross resistance that evolved to an earlier, widely used insecticide. In the current study we examined cross-resistance of selected D. melanogaster strains to propoxur, a likely candidate carbamate insecticide that has been extensively used during the past 3 decades. However, no correlation between resistance to lufenuron and propoxur was found. Strains were selected to represent a range of dates of establishment (1936-1996) from natural populations to laboratory culture. Examination of these strains showed susceptibility to propoxur in long established laboratory strains, but resistance in recently established strains. Susceptibility to lufenuron was also high in long-established strains and apparently slowly decreased in natural populations until approximately equal to 5 yr ago, when it decreased more rapidly. These results suggest that if this loss in susceptibility results from agricultural chemical usage, then these chemicals can significantly affect a non-target insect. PMID- 9374594 TI - Cyromazine toxicity to Drosophila melanogaster (Diptera: Drosophilidae) and lack of cross-resistance in natural population strains. AB - Cyromazine is an insect growth regulator (IGR) insecticide that is effective against Drosophila melanogaster (Meigen). Both larvae and pupae of a standard laboratory strain were killed over an extremely narrow range of 0.3-0.5 ppm incorporated into the diet. Higher toxic doses killed larvae more rapidly, and lower toxic doses allowed pupariation but usually blocked pupal development. These puparia were abnormally elongated, indicating a failure of the contraction process that produces the characteristic pupal shape. When fed to adults, cyromazine had no effect on adult survival, fecundity, or fertility, even at a 10 fold larval LC50 level. In previous work, D. melanogaster strains recently derived from natural populations were found to be 25- to 100-fold resistant to at least 2 other classes of insecticides, chitin-synthesis inhibitors and carbamates. Here I tested 9 additional strains that were recently selected from widely separated geographical locations in the United States and found them to have resistance to lufenuron and propoxur, but virtually no resistance to cyromazine relative to one another or to 3 long-established laboratory strains. The results show that cross-resistance between the IGRs lufenuron and cyromazine is not present in D. melanogaster. They further suggest that cyromazine control failure in pest insect populations caused by cross-resistance may be minimal. PMID- 9374596 TI - Efficacy of a dehydrated steinernematid nematode against black cutworm (Lepidoptera: Noctuidae) and diamondback moth (Lepidoptera: Plutellidae). AB - We compared the ability of in vitro-produced, commercially formulated with in vivo-produced, nonformulated Steinernema carpocapsae (Weiser) Poinar. All strain to infect and kill larvae of black cutworm, Agrotis ipsilon (Hufnagel), and diamondback moth, Plutella xylostella (L.). In vitro-produced nematodes formulated in wettable dispersible granules, which were stored dry, were rehydrated in water for 0-72 h before application. Against black cutworms, the efficacy of nematodes was (from most to least effective): in vivo > in vitro rehydrated for 72 h > in vitro rehydrated for 48 h > in vitro rehydrated for 24 h > dehydrated (0 h). Nematodes rehydrated for 72 h in water or moist soil were equally effective against black cutworm larvae, and both were significantly more effective than nematodes without rehydration. These results indicated that nematodes in the wettable dispersible granule formulation required time to rehydrate in the soil before infecting black cutworm larvae. Nematode treatments described above were applied to radish plants held at 100 or 75% RH and tested against diamondback moth larvae. At 100% RH, nematode efficacy was (from most to least effective): in vitro rehydrated for 72 h > in vivo > in vitro rehydrated 48 h > in vitro rehydrated 24 h > dehydrated (0 h). The efficacy of all treatments was lower at 75% than at 100% RH, and the ranking of in vivo and in vitro nematodes rehydrated for 72 h was reversed. The nematodes in the wettable dispersible granule formulation were effective for foliar treatments when humidity was high and nematodes were rehydrated for at least 48 h before application. The data show that nematode infectivity was reduced unless nematodes were rehydrated. PMID- 9374595 TI - Interactions of recombinant and wild-type baculoviruses with classical insecticides and pyrethroid-resistant tobacco budworm (Lepidoptera: Noctuidae). AB - In tests with neonate Heliothis virescens (F.), we characterized interactions of all combinations of a recombinant Autographa californica (Speyer) nuclear polyhedrosis virus (AcAaIT) that expresses an insect-selective neurotoxin (AaIT) and wild-type AcNPV when combined with low concentrations of several conventional insecticides. All combinations of the recombinant virus AcAaIT and insecticides showed a positive interaction (decrease in the median lethal time (LT50) compared with the LT50 for either component alone). A type II pyrethroid (cypermethrin, which modifies currents of sodium channels) and a carbamate (methomyl, an inhibitor of acetylcholinesterase) were synergistic in combination with AcAaIT. Other insecticides also showed a positive interaction when tested in combination with the recombinant virus, but joint activity was slightly antagonistic (i.e., less than predicted activity when combined) with wild-type AcNPV. We also characterized the effectiveness of AcAaIT against pyrethroid-resistant H. virescens larvae. Our results show that a resistant strain of H. virescens is more sensitive to the recombinant virus compared with a susceptible strain. Results of these studies should be useful in planning of future field trials to increase the effectiveness of nuclear polyhedrosis viruses and to manage resistance to pyrethroids and other insecticides. PMID- 9374597 TI - Effect of ecdysteroid UDP-glucosyltransferase gene deletion on efficacy of a baculovirus against Heliothis virescens and Trichoplusia ni (Lepidoptera: Noctuidae). AB - Laboratory, greenhouse, and field studies were conducted to characterize the biological activity of a genetically altered form of Autographa californica (Speyer) nucleopolyhedrosis virus (AcNPV). The altered baculovirus (vEGTDEL) had a deletion in the ecdysteroid UDP-glucosyltransferase gene. Results from bioassays conducted with neonate and 3rd-instar tobacco budworm, Heliothis virescens (F.), as well as with 3rd-instar cabbage looper, Trichoplusia ni (Hubner), showed vEGTDEL caused larval death slightly, but significantly, quicker than AcNPV. Based on supposition (LT50 values were not calculated), it appeared that larval mortality occurred 0.5-1.0 d faster following exposure to vEGTDEL versus AcNPV. Greenhouse studies conducted against H. virescens on cotton showed that hastened virulence exhibited by vEGTDEL led to improved plant protection versus AcNPV. For example, following 5 weekly sessions of foliar application and H. virescens artificial infestation, cotton treated with wettable powder formulations of vEGTDEL or AcNPV at 2.5 x 10(12) OB/ha averaged 25.7 and 61.8% damaged flower buds, respectively. Although vEGTDEL tended to provide more consistent control of T. ni than AcNPV in greenhouse and field trials conducted on leafy vegetables, differences in efficacy between the 2 baculoviruses were marginal and usually not statistically significant. Generally, results from these studies suggest that genetic modification of NPVs to hasten their lethal effect may be a promising strategy for improving the insecticidal properties of the insect-specific pathogens. PMID- 9374598 TI - Comparison of traps and development of a two-stage sampling plan for smokybrown cockroaches (Dictyoptera: Blattidae) outdoors. AB - Four commercial sticky traps were compared with jar traps for sampling smokybrown cockroaches, Periplaneta fuliginosa (Serville), outdoors. Lo-Line and Raid Roach Traps caught more cockroaches than jar traps, whereas the Mr. Sticky and Roach Motel caught < 40% of the cockroaches caught in jar traps. Sampling properties of traps (data collected over 4 yr and 3 cities) were examined retrospectively. Taylor's a and b coefficients were both significantly > 1 for jar traps, Raid Roach Trap, and Lo-Line trap. Estimating cockroach catch typical of Alabama (< 3 per trap) at single houses would require > 20 traps with a precision of 0.25 (i.e., standard error as a proportion of the mean). Taylor's power law was also used as a predictor for within-house (i.e., pooled within-house) and between house catch variances. Coefficients for these predictors are presented that can be used in a fixed-precision 2-stage sampling plan to estimate cockroach catch from large areas. PMID- 9374599 TI - Evaluation of methods of insecticide application for control of smokybrown cockroaches (Dictyoptera: Blattidae). AB - The insecticide components of a previously developed integrated pest management system for smokybrown cockroaches, Periplaneta fuliginosa (Serville), were tested individually and at reduced application rates in 4 separate trials over 2 yr. A 2 bait combination (pellet and gel baits) did not significantly reduce cockroach abundance more than a single constituent bait alone. A targeted spray of trelamethrin was significantly less effective than a 2-bait combination. Residual activity of insecticides was determined with American cockroaches, P. americana (L.), in a laboratory bioassay. Chlorpyrifos wettable powder remained active < 12 d in the field, after which time its activity was not different from an experimental control (no insecticide residues), whereas chlorpyrifos pellet and hydramethylnon paste baits retained initial activity for > 27 d. Nematodes [Steinernema carpocapsae (Weiser)] applied as a spray solution did not effect the abundance of smokybrown cockroaches, and no cockroaches were recovered that exhibited nematode infection. Time needed to apply various insecticide treatments did not differ substantially (15-25 min per house), even for lower application rates. PMID- 9374602 TI - On the power of confession evidence: an experimental test of the fundamental difference hypothesis. AB - In Arizona v. Fulminante (1991), a U.S. Supreme Court majority stated that confessions are similar to, not fundamentally different from, other types of evidence. To evaluate this claim, three mock juror studies compared the impact of confessions to other common forms of evidence. In Experiment 1, participants read summaries of four criminal trials (murder, rape, assault, theft), each of which contained a confession, an eyewitness identification, character testimony, or none of the above. Significantly, the confessions produced the highest conviction rates. In Experiments 2 and 3, participants read a murder or assault trial containing all three types of evidence and made a series of midtrial judgments. Results indicated that the confession was seen as the most incriminating, followed by the eyewitness and character testimony. Although the comparisons we made are limited in certain respects, our findings suggest that confessions are uniquely potent. PMID- 9374603 TI - The impact of graphic photographic evidence on mock jurors' decisions in a murder trial: probative or prejudicial? AB - Although courts in the United States and Canada regularly admit graphic photographs into evidence, little research exists on whether such evidence prejudices the decisions of jurors. Mock jurors (N = 120) read a detailed trial transcript of a murder trial, and were either presented with color, black and white, or no photographs of an actual murder victim. The proportion of guilty verdicts in the color and the black and white photograph conditions was approximately double that in the control condition. Both groups were more likely than the control condition to report emotional distress and physical reactions in response to viewing the photographs. By contrast, there were few differences between groups concerning the extent to which participants felt that the photographs influenced verdicts. Participants in all conditions equally felt that they had acted fairly. Implications surrounding the admissibility of graphic photographic evidence, and the seeming inability of participants to recognize that their judgments were biased, are discussed. PMID- 9374605 TI - A comparison of retained and appointed counsel in cases of capital murder. AB - We examined the role of counsel as a source of arbitrary and capricious sentencing in cases of capital murder. The method is a reanalysis of the data of Baldus, Woodworth, & Pulaski (1990) on 606 cases of capital murder in Georgia in the 1970s. Controlling for variables describing the character of the defendant and the circumstances of the crime, a death sentence was more likely when defense counsel was appointed rather than retained privately. This was a consequence primarily of the prosecutor's decision to seek a death sentence rather than jury bias in sentencing. Our data support the conclusion that sentencing under the Georgia statute was in the 1970s, and is today to some degree, arbitrary and capricious. PMID- 9374604 TI - Co-witness information can have immediate effects on eyewitness memory reports. AB - When questioning a reluctant witness, investigators sometimes encourage the witness by providing information about what other witnesses have said. Three experiments were conducted to test the combined effects of such co-witness information and suggestive questioning on the accuracy of eyewitness memory reports. Experiment 1 was analogous to the experience of a witness who receives information from an interviewer or questioner about what other witnesses have already said, whereas Experiments 2 and 3 simulated the situation in which a witness receives information directly from a co-witness. In all three experiments, when participants received incorrect information about a co witness's response, they were significantly more likely to give that incorrect response than if they received no co-witness information. This effect persevered in a delayed memory test 48 h after the initial questioning session in Experiment 3. Accuracy rates were lowest of all when incorrect co-witness information was paired with questioning that suggested an incorrect response. These results have implications not only for the immediate effects on the accuracy of witnesses' memory reports, but also for the impact that even one such inaccurate report can have on the manner in which a case is investigated by the police or other authorities. PMID- 9374607 TI - Will Pru keep caring? PMID- 9374606 TI - An integration of hindsight bias and counterfactual thinking: decision-making and drug courier profiles. AB - Counterfactual thinking and hindsight bias have each generated separate, substantial bodies of research and provided insight into some areas of legal decision-making. An investigation of the relationship between counterfactual thinking and hindsight bias in a situation in which both are implicated is presented in a legal decision-making context utilizing drug courier profiles and illegal search and seizure. The findings, which demonstrate each of these cognitive processes and show a pattern of results that supports an integrative relationship between them, are discussed in the contexts of social cognition and of legal decision-making. A suggested causal model of decision-making in this context is also presented. Specific implications of these findings for civil actions to remedy illegal searches are discussed. PMID- 9374608 TI - Medicare cutbacks. Fallout from the big freeze. PMID- 9374609 TI - Disproportionate share. Where the hits will hurt. PMID- 9374610 TI - Physician pay. To them, managed care looks good. PMID- 9374611 TI - Public health ... a little bit of penicillin could quickly banish bacteria. PMID- 9374612 TI - Managed care. One pick, two pans. PMID- 9374613 TI - Insurance reform. What's the beef? PMID- 9374614 TI - Coverage ... the ranks of the uninsured are growing. PMID- 9374615 TI - Quality watch ... Staphylococcus aureus is growing increasingly resistant to drugs. PMID- 9374616 TI - The leveraged buy is out. AB - While purchasing giants Premier and VHA jockey for market share, signs show they're looking for competition in all the wrong places. Some of their own members, having merged into powerful regional systems, say they've built up the buying muscle capable of getting better deals from suppliers. PMID- 9374617 TI - Russian rehab. AB - The eagle has landed, bringing American clinics and even managed care to Russia's ailing state health care system. But so far, that's treatment only the elite--the richest 1 percent--can afford. PMID- 9374618 TI - Their world is the ghetto. AB - Though small and struggling, minority-run HMOs have taught their larger rivals a lesson or two about serving the community. Unfortunately, Medicaid rate cuts make it harder and harder to serve the poor without going broke. PMID- 9374619 TI - Fit to be tried. Despite some notable failures, integrated care is still the best bet for cutting costs, not quality. PMID- 9374620 TI - Conversions. Turnabout is fair play. PMID- 9374621 TI - Medicare options. Pressing for change. PMID- 9374622 TI - CON laws. Will the market build to suit? PMID- 9374623 TI - Premium hikes. Where's our$? PMID- 9374624 TI - Hospital pulse ... June 1997. PMID- 9374625 TI - Medical record privacy. Open secrets. PMID- 9374626 TI - Malpractice claims. Best defense is no offense. PMID- 9374627 TI - Regulation of tPA in endothelial cells exposed to cyclic strain: role of CRE, AP 2, and SSRE binding sites. AB - We have previously reported that exposure of cultured bovine aortic endothelial cells (EC) to 10% average strain resulted in an increase in tissue plasminogen activator (tPA) mRNA, immunoreactive tPA protein, and tPA activity in the medium. The present study was designed to examine the regulation of tPA gene expression in EC by cyclic strain. We performed a functional analysis of the tPA promoter by transfecting bovine aortic EC with a 1.4-kilobase (kb) construct of the human tPA promoter coupled to chloramphenicol acetyltransferase. We found that subjecting the EC to 10% average strain (and not 6% average strain) resulted in a 2.6-fold increase in activity of the 1.4-kb tPA promoter by 4 h. Analysis of deletion mutants of the promoter transfected into EC demonstrated a 60% drop-off in activity between position -145 and -105. Deoxyribonuclease I protection analysis of the segment downstream of position -196 suggested involvement of activator protein-2 (AP-2) and adenosine 3',5'-cyclic monophosphate-responsive element (CRE)-like binding sites, which was confirmed by electrophoretic mobility shift assays. Site-directed mutants of either the AP-2 or CRE-like regions resulted in a 65% decrease in activity compared with the wild type. Double mutations abolished basal transcription and any strain-induced activity. A shear stress responsive element (SSRE) binding site is present at -945, but site-directed mutants did not show any drop in activity compared with wild type by cyclic strain. These studies demonstrate that cyclic strain regulates tPA gene transcription in bovine aortic EC and that this transcriptional activation is dependent on factors that are similar to those activated with phorbol ester. PMID- 9374628 TI - CCK-B receptors produce similar signals but have opposite growth effects in CHO and Swiss 3T3 cells. AB - Rat cholecystokinin-B (CCK-B) receptors were transfected into Chinese hamster ovary (CHO)-K1 (CHO-CCK-B) and Swiss 3T3 (Swiss 3T3-CCK-B) cells, and the effects of receptor activation on cell proliferation and intracellular signaling were investigated. CCK octapeptide (CCK-8) treatment had no effect on cell growth in quiescent CHO-CCK-B cells but inhibited DNA synthesis, proliferation, and colony formation when the cells were grown in fetal bovine serum (FBS). In contrast, CCK 8 stimulated DNA synthesis in quiescent Swiss 3T3-CCK-B cells and had no effect when the cells were grown in FBS. These differences in growth responses were not due to differences in the level of receptor expression, as similar numbers of receptors were present in both cell types. To determine whether the different growth effects were due to differences in receptor coupling to common second messenger pathways, we investigated the effects of CCK-8 on several known intracellular signals. In both cell types, CCK-8 stimulated increases in intracellular Ca2+ concentration and polyphosphoinositide hydrolysis with similar potencies and efficacies. CCK-8 also stimulated arachidonate release from both cell types, although the potency was higher in the CHO cells. Adenosine 3',5' cyclic monophosphate generation was observed at high agonist concentrations in both cell types and was much greater in cells with higher receptor density. In summary, receptor activation had opposite effects on growth parameters in CHO and Swiss 3T3 cells, but only minor differences were observed in the characteristics of CCK-B receptor coupling to specific second messengers in the two cell types. Thus cellular context is a principal determinant of the biological effects of CCK B receptor activation, and differences in biological responses may occur independently of major differences in receptor coupling. PMID- 9374629 TI - Receptor-mediated inhibition of renal Na(+)-K(+)-ATPase is associated with endocytosis of its alpha- and beta-subunits. AB - The mechanisms involved in receptor-mediated inhibition of Na(+)-K(+)-ATPase remain poorly understood. In this study, we evaluate whether inhibition of proximal tubule Na(+)-K(+)-ATPase activity by dopamine is linked to its removal from the plasma membrane and internalization into defined intracellular compartments. Clathrin-coated vesicles were isolated by sucrose gradient centrifugation and negative lectin selection, and early and late endosomes were separated on a flotation gradient. Inhibition of Na(+)-K(+)-ATPase activity by dopamine, in contrast to its inhibition by ouabain, was accompanied by a sequential increase in the abundance of the alpha-subunit in clathrin-coated vesicles (1 min), early endosomes (2.5 min), and late endosomes (5 min), suggesting its stepwise translocation between these organelles. A similar pattern was found for the beta-subunit. The increased incorporation of both subunits in all compartments was blocked by calphostin C. The results demonstrate that the dopamine-induced decrease in Na(+)-K(+)-ATPase activity in proximal tubules is associated with internalization of its alpha- and beta-subunits into early and late endosomes via a clathrin-dependent pathway and that this process is protein kinase C dependent. The presence of Na(+)-K(+)-ATPase subunits in endosomes suggests that these compartments may constitute normal traffic reservoirs during pump degradation and/or synthesis. PMID- 9374630 TI - Role of prostaglandin H synthase-2-mediated conversion of arachidonic acid in controlling 3T6 fibroblast growth. AB - The specific role(s) of arachidonic acid (AA) and its metabolites in the signaling pathways that regulated fibroblast growth was studied. A Western blot analysis demonstrated that prostaglandin H synthase-2 (PGHS-2) was expressed by 3T6 fibroblast cultures in RPMI 1640 supplemented with fetal calf serum (10%). Dexamethasone, which inhibits AA release and PGHS-2 expression, significantly reduced cell proliferation. Ketoprofen, a dual cyclooxygenase inhibitor, and CGP 28238, a specific PGHS-2 inhibitor, reduced fibroblast proliferation in a dose dependent manner. These drugs also reduced [3H]thymidine incorporation into the DNA of fibroblasts. These effects were correlated with a decrease in prostaglandin (PG) E2 levels in the cell medium. However, piroxicam at doses that selectively inhibit PGHS-1 did not have a significant effect on fibroblast proliferation. Finally, we showed that the antiproliferative effect of dexamethasone and PGHS-2 inhibitors was significantly antagonized when PGE2 was added to the culture medium. Our results suggest that PGHS-2 and prostaglandins such as PGE2 might play an important role in the regulation of 3T6 fibroblast growth stimulated by growth factors of serum. PMID- 9374631 TI - Cholecystokinin and EGF activate a MAPK cascade by different mechanisms in rat pancreatic acinar cells. AB - The effects of activating the Gq protein-coupled cholecystokinin (CCK) receptor on different proteins/signaling molecules in the mitogen-activated protein kinase (MAPK) cascade in pancreatic acinar cells were analyzed and compared with the effects of activating the tyrosine kinase-coupled epidermal growth factor (EGF) receptor. Both EGF and CCK octapeptide rapidly increased the activity of the MAPKs [extracellular signal-regulated kinase (ERK) 1 and ERK2], reaching a maximum within 2.5 min when 3.9- and 8.5-fold increases, respectively, were observed. The EGF-induced increase of MAPK activity was transient, with only a slight elevation after 30 min, whereas CCK-stimulated MAPK remained at a high level of activation to 60 min. The protein kinase C inhibitor GF-109203X abolished the activation by phorbol ester and inhibited the effect of CCK by 78% but had no effect on EGF-activated MAPK activity. EGF and CCK activated both forms of MAPK kinase (MEK), with CCK having a much larger effect, activating MEK1 by 6-fold and MEK2 by 10-fold, whereas EGF activated both MEKs by only 2-fold. Immunoblotting revealed three different forms of Raf in pancreatic acinar cells. Of the total basal Raf kinase activity, 3.7% was Raf-A, 89.0% was Raf-B, and 7.3% was c-Raf-1. All three forms of Raf were stimulated to a greater extent by CCK than by EGF, which was especially evident for Raf-A and c-Raf-1. The effect of CCK in activating Rafs was at least partially mimicked by stimulation with the phorbol ester 12-O-tetradecanoylphorbol-13-acetate. EGF significantly increased GTP-bound Ras by 183 and 164% at 2.5 and 10 min, respectively; CCK and TPA had no measurable effect. Our study suggests that CCK and EGF activate the MAPK cascade by distinct mechanisms in pancreatic acinar cells. PMID- 9374632 TI - Fluid and ion transport in corneal endothelium: insensitivity to modulators of Na(+)-K(+)-2Cl- cotransport. AB - The role of Na(+)-K(+)-2Cl- cotransport in ion and fluid transport of the corneal endothelium was examined by measuring changes in corneal hydration and uptake of 86Rb by the endothelial cell layer. Isolated, intact rabbit corneas maintain normal hydration when they are superfused at the endothelial surface with bicarbonate (HCO3-)-Ringer solutions as a result of equilibrium between active ion and fluid transport out of the stromal tissue and leak of fluid into stromal tissue from the aqueous humor. Furosemide and bumetanide did not alter this equilibrium when they were added to the superfusion medium. Uptake of 86Rb by the endothelium of the incubated cornea was increased 25% by bumetanide, but uptake in the presence of ouabain (70% less than that of controls) was not changed by bumetanide. In Na(+)-free medium, uptake of 86Rb was reduced by 58%, but it was unchanged in Cl(-)-free medium. Calyculin A, a protein phosphatase inhibitor and activator of Na(+)-K(+)-Cl- cotransport, was without effect on 86Rb uptake. Hypertonicity (345 mosmol/kg) increased uptake slightly, whereas hypotonicity (226 mosmol/kg) caused a 33% decrease. Neither of these changes was significantly different when bumetanide was present in the media. It is concluded that Na(+) K(+)-2Cl- cotransporter activity is not exhibited by the in situ corneal endothelium and does not play a role in the ion and fluid transport of this cell layer. Its presence in cultured endothelial cells may reflect the reported importance of this protein in growth, proliferation, and differentiation. PMID- 9374633 TI - Mitochondrial function in oncogene-transfected rat fibroblasts isolated from multicellular spheroids. AB - Two mitochondrion-specific fluorochromes, 10-N-nonyl acridine orange (NAO) and rhodamine 123 (Rh123), were used to determine the mechanism responsible for alterations in energy metabolism of transformed rat embryo fibroblast cells isolated from different locations within multicellular spheroids. Accumulation of Rh123 depends on intact mitochondrial membrane potential, whereas NAO is taken up by mitochondria independently of their function and thus represents mitochondrial distribution only. A reproducible selective dissociation procedure was used to isolate cells from different locations within the spheroids. After isolation, cells were simultaneously stained with one mitochondrial stain and the DNA dye Hoechst 33342, and several parameters, including cell volume, were monitored via multilaser-multiparameter flow cytometry. Our data clearly show a decrease in the uptake of Rh123 in cells from the periphery to the inner regions of the tumor spheroids, reflecting a persistent alteration in mitochondrial function. However, NAO staining experiments showed no reduction in the total mitochondrial mass per unit cell volume. Because cells were exposed to stain under uniform conditions after isolation from the spheroid, these data indicate the downregulation of mitochondrial function is associated with cell quiescence rather than a transient effect of reduced nutrient availability. This result, which is in accordance with data from two other cell lines (EMT6 and 9L), might reflect a general phenomenon in multicellular spheroids, supporting the hypothesis that quiescent cells in the innermost viable spheroid layer stably reduce their mitochondrial function, presumably to compensate for lower nutrient supply and/or decreased energy demand. PMID- 9374634 TI - Tissue distribution of Na+/H+ exchanger isoforms NHE2 and NHE4 in rat intestine and kidney. AB - We present evidence that tissue distribution of two highly conserved Na+/H+ exchanger isoforms, NHE2 and NHE4, differs significantly from previously published reports. Riboprobes unique to each of these antiporters, from 5' (noncoding and coding) and 3' coding regions, were used to analyze mRNA from adult rat kidney and intestine by ribonuclease protection assay and in situ hybridization. In contrast to earlier work that concluded that both NHE2 and NHE4 were expressed throughout the intestine and in the kidney, our data show that there is no NHE2 message in the kidney and NHE4 is not expressed in small or large intestine. Analyses of intestinal epithelial and kidney membrane proteins by an NHE2-specific antibody identified a doublet at < 90 kDa in intestine but not in kidney. NHE2 is highly expressed in the Na(+)-absorptive epithelium of jejunum, ileum, and ascending and descending colon. NHE4 mRNA message is found in the inner medulla of the kidney as previously reported (C. Bookstein, M. W. Musch, A. DePaoli, Y. Xie, M. Villereal, M. C. Rao, and E. B. Chang. J. Biol. Chem. 269: 29704-29709, 1994) and not in the intestine. From these data, we speculate that neither NHE2 nor NHE4 has a role in renal Na+ absorption. NHE2 is likely involved in gut Na+ absorption, whereas NHE4 may have a specialized role in cell volume rectification of inner medullary collecting duct cells. Knowledge of the correct tissue and cell-specific distribution of these two antiporters should help significantly in understanding their physiological roles. PMID- 9374635 TI - Negative transcriptional regulation of the VCAM-1 gene by fluid shear stress in murine endothelial cells. AB - To explore the mechanism of shear stress-induced downregulation of vascular cell adhesion molecule 1 (VCAM-1) expression in murine endothelial cells (ECs), we examined the effect of shear stress on VCAM-1 gene transcription and assessed the cis-acting elements involved in this phenomenon. VCAM-1 mRNA expression was downregulated at the transcriptional level as defined by nuclear run-on assay and transient transfection of VCAM-1 promoter-luciferase gene constructs. The luciferase assay on the VCAM-1 deletion mutants revealed that the cis-acting element is contained between -694 and -329 bp upstream from the transcription initiation site. Gel shift assay using overlapping oligonucleotide probes of this region showed that oligonucleotides containing a double AP-1 consensus sequence (TGACTCA) formed distinct complexes with nuclear proteins extracted from shear stressed cells. Mutation of either one or both of two AP-1 consensus sequences completely abolished the ability of the promoter to respond to shear stress. These results suggest that fluid shear stress downregulates the transcription of the VCAM-1 gene via an upstream cis-element, a double AP-1 consensus sequence, in murine lymph node venule ECs. PMID- 9374636 TI - Functional characterization of the neuronal-specific K-Cl cotransporter: implications for [K+]o regulation. AB - The neuronal K-Cl cotransporter isoform (KCC2) was functionally expressed in human embryonic kidney (HEK-293) cell lines. Two stably transfected HEK-293 cell lines were prepared: one expressing an epitope-tagged KCC2 (KCC2-22T) and another expressing the unaltered KCC2 (KCC2-9). The KCC2-22T cells produced a glycoprotein of approximately 150 kDa that was absent from HEK-293 control cells. The 86Rb influx in both cell lines was significantly greater than untransfected control HEK-293 cells. The KCC2-9 cells displayed a constitutively active 86Rb influx that could be increased further by 1 mM N-ethylmaleimide (NEM) but not by cell swelling. Both furosemide [inhibition constant (Ki) approximately 25 microM] and bumetanide (Ki approximately 55 microM) inhibited the NEM-stimulated 86Rb influx in the KCC2-9 cells. This diuretic-sensitive 86Rb influx in the KCC2-9 cells, operationally defined as KCC2 mediated, required external Cl- but not external Na+ and exhibited a high apparent affinity for external Rb+(K+) [Michaelis constant (Km) = 5.2 +/- 0.9 (SE) mM; n = 5] but a low apparent affinity for external Cl- (Km > 50 mM). On the basis of thermodynamic considerations as well as the unique kinetic properties of the KCC2 isoform, it is hypothesized that KCC2 may serve a dual function in neurons: 1) the maintenance of low intracellular Cl- concentration so as to allow Cl- influx via ligand-gated Cl- channels and 2) the buffering of external K+ concentration ([K+]o) in the brain. PMID- 9374638 TI - P2 purinoceptor of the globular substance in the otoconial membrane of the guinea pig inner ear. AB - The biological characteristics of the globular substance, a precursor of otoconia, are unclear. In the present study, the ATP-induced internal free Ca2+ concentration ([Ca2+]i) changes of the globular substance and the ATP distribution in the vestibular organ were investigated using a Ca2+ indicator, fluo 3, and an adenine nucleotide-specific fluorochrome, quinacrine, by means of confocal laser scanning microscopy. [Ca2+]i showed a rapid and dose-dependent increase in response to ATP with a 50% effective concentration (EC50) of 16.7 microM. This reaction was independent of external Ca2+, indicating the presence of an internal Ca2+ reservoir. Neither adenosine, alpha, beta-methylene-ATP, 3'-O (4-benzoylbenzoyl)-ATP, ADP, nor UTP evoked this reaction, whereas 2-methylthio ATP induced an increase of [Ca2+]i with an EC50 of 14.4 microM. Moreover, P2 antagonists, reactive blue 2 and suramin, and a phospholipase C inhibitor, U 73122, inhibited the ATP-induced [Ca2+]i increase. These findings indicate the presence of a P2Y purinoceptor on the globular substance. In addition, granular fluorescence was observed in the quinacrine-stained macular sensory epithelium, indicating the presence of ATP-containing granules in this tissue. These results suggest that a paracrine mechanism involving ATP may exist in the macula and that this mechanism regulates the biological behavior of the globular substance. PMID- 9374637 TI - Hormone-induced rise in cytosolic Ca2+ in axolotl hepatocytes: properties of the Ca2+ influx channel. AB - Calcium entry in nonexcitable cells occurs through Ca(2+)-selective channels activated secondarily to store depletion and/or through receptor- or second messenger-operated channels. In amphibian liver, hormones that stimulate the production of adenosine 3',5'-cyclic monophosphate (cAMP) also regulate the opening of an ion gate in the plasma membrane, which allows a noncapacitative inflow of Ca2+. To characterize this Ca2+ channel, we studied the effects of inhibitors of voltage-dependent Ca2+ channels and of nonselective cation channels on 8-bromoadenosine 3',5'-cyclic monophosphate (8-BrcAMP)-dependent Ca2+ entry in single axolotl hepatocytes. Ca2+ entry provoked by 8-BrcAMP in the presence of physiological Ca2+ followed first-order kinetics (apparent Michaelis constant = 43 microM at the cell surface). Maximal values of cytosolic Ca2+ (increment approximately 300%) were reached within 15 s, and the effect was transient (half time of 56 s). We report a strong inhibition of cAMP-dependent Ca2+ entry by nifedipine [half-maximal inhibitory concentration (IC50) = 0.8 microM], by verapamil (IC50 = 22 microM), and by SK&F-96365 (IC50 = 1.8 microM). Depolarizing concentrations of K+ were without effect. Gadolinium and the anti-inflammatory compound niflumate, both inhibitors of nonselective cation channels, suppressed Ca2+ influx. This "profile" indicates a novel mechanism of Ca2+ entry in nonexcitable cells. PMID- 9374639 TI - Aquaporins in complex tissues. I. Developmental patterns in respiratory and glandular tissues of rat. AB - Developmental expression of aquaporin water transport proteins is not well understood in respiratory tract or secretory glands; here we define aquaporin protein ontogeny in rat. Expression of aquaporin-3 (AQP3), AQP4, and AQP5 proteins occurs within 2 wk after birth, whereas AQP1 first appears before birth. In most tissues, aquaporin protein expression increases progressively, although transient high-level expression is noted in distal lung (AQP4 at postnatal day +2) and trachea (AQP5 at postnatal day +21 and AQP3 at postnatal day +42). In mature animals, AQP5 is abundant in distal lung and salivary glands, AQP3 and AQP4 are present in trachea, and AQP1 is present in all of these tissues except salivary glands. Surprisingly, all four aquaporin proteins are highly abundant in nasopharynx. Unlike AQP1, corticosteroids did not induce expression of AQP3, AQP4, or AQP5 in lung. Our results seemingly implicate aquaporins in proximal airway humidification, glandular secretion, and perinatal clearance of fluid from distal airways. However, the studies underscore a need for detailed immunohistochemical characterizations and definitive functional studies. PMID- 9374640 TI - Aquaporins in complex tissues. II. Subcellular distribution in respiratory and glandular tissues of rat. AB - The molecular pathways for fluid transport in pulmonary, oral, and nasal tissues are still unresolved. Here we use immunocytochemistry and immunoelectron microscopy to define the sites of expression of four aquaporins in the respiratory tract and glandular epithelia, where they reside in distinct, nonoverlapping sites. Aquaporin-1 (AQP1) is present in apical and basolateral membranes of bronchial, tracheal, and nasopharyngeal vascular endothelium and fibroblasts. AQP5 is localized to the apical plasma membrane of type I pneumocytes and the apical plasma membranes of secretory epithelium in upper airway and salivary glands. In contrast, AQP3 is present in basal cells of tracheal and nasopharyngeal epithelium and is abundant in basolateral membranes of surface epithelial cells of nasal conchus. AQP4 resides in basolateral membranes of columnar cells of bronchial, tracheal, and nasopharyngeal epithelium; in nasal conchus AQP4 is restricted to basolateral membranes of a subset of intra- and subepithelial glands. These sites of expression suggest that transalveolar water movement, modulation of airway surface liquid, air humidification, and generation of nasopharyngeal secretions involve a coordinated network of aquaporin water channels. PMID- 9374641 TI - Aqp1 expression in erythroleukemia cells: genetic regulation of glucocorticoid and chemical induction. AB - The aquaporin-1 (AQP1) water channel protein is expressed in multiple mammalian tissues by several different developmental programs; however, the genetic regulation is undefined. The proximal promoter of mouse Aqp1 contains multiple putative cis-acting regulatory elements, and mouse erythroleukemia (MEL) cells are a well-characterized model for erythroid differentiation. Corticosteroid or dimethyl sulfoxide (DMSO) exposure induces AQP1 protein expression in MEL cells, and transcriptional regulation was investigated by transient transfections with Aqp1 promoter-reporter constructs. Dexamethasone induction is abrogated by deletion of two glucocorticoid response elements -0.5 kilobases (kb) from the transcription initiation site. Mutation of the GATA element at -0.62 kb has no effect, whereas mutation of the CACCC site at -37 bp significantly reduces DMSO induced promoter activity. Hydroxyurea induces expression of AQP1 protein without acting through the proximal promoter. The MEL cell line is a reproducible erythroid model system for studying transcriptional regulation of the Aqp1 gene while determining the consequences on AQP1 protein biosynthesis. PMID- 9374642 TI - Hypoxia enhances induction of endothelial ICAM-1: role for metabolic acidosis and proteasomes. AB - Intercellular adhesion molecule 1 (ICAM-1) is an important molecule in promotion of polymorphonuclear neutrophil transendothelial migration during inflammation. Coincident with many inflammatory diseases is tissue hypoxia. Thus we hypothesized that combinations of hypoxia and inflammatory stimuli may differentially regulate expression of endothelial ICAM-1. Human endothelial cells were exposed to hypoxia in the presence or absence of added lipopolysaccharide (LPS) and examined for expression of functional ICAM-1. Although hypoxia alone did not induce ICAM-1, the combination of LPS and hypoxia enhanced (3 +/- 0.4 fold over normoxia) ICAM-1 expression. Combinations of hypoxia and LPS significantly increased lymphocyte binding, and such increases were inhibited by addition of anti-ICAM-1 antibodies or antisense oligonucleotides. Hypoxic endothelia showed a > 10-fold increase in sensitivity to inhibitors of proteasome activation, and combinations of hypoxia and LPS enhanced proteasome-dependent cytoplasmic-to-nuclear localization of the nuclear transcription factor-kappa B p65 (Rel A) subunit. Such proteasome activation correlated with hypoxia-evoked decreases in both extracellular and intracellular pH. We conclude from these studies that endothelial hypoxia provides a novel, proteasome-dependent stimulus for ICAM-1 induction. PMID- 9374643 TI - Nitric oxide enhances hydrogen peroxide-mediated endothelial permeability in vitro. AB - The objective of this study was to evaluate the effects of nitric oxide (NO) on H2O2-mediated endothelial permeability. H2O2 (0.1 mM) increased permeability at 90 min to 298% of baseline. Spermine NONOate (SNO), an NO donor, at 0.1 or 1 mM did not alter permeability. However, 0.1 mM H2O2 + 1 mM SNO increased permeability to 764%, twice that of 0.1 mM H2O2 alone. These treatments were not directly toxic to endothelial cells. This NO effect was concentration dependent, inasmuch as 0.1 mM SNO did not significantly change H2O2-mediated permeability. The NO-enhanced, H2O2-dependent permeability required the simultaneous presence of NO and H2O2, inasmuch as preincubation with SNO for 30 min followed by 0.1 mM H2O2 did not alter permeability. Staining of endothelial junctions showed widening of the intercellular space only in junctions of cells exposed to H2O2 (0.1 mM) + SNO (1 mM). Furthermore, NO did not affect H2O2 metabolism by endothelial cells but significantly depleted intracellular glutathione. This reduction of cell glutathione produced by NO exposure recovered 15-30 min after removal of the NO donor. NO-enhanced permeability was completely blocked by methionine (1 mM), a scavenger of reactive oxygen species, and by the iron chelator desferrioxamine (0.1 mM). These results suggest that NO may exacerbate the effects of H2O2-dependent increase in endothelial monolayer permeability via the iron-catalyzed formation of reactive oxygen metabolites. PMID- 9374645 TI - Permeability properties of monolayers of the human trophoblast cell line BeWo. AB - The BeWo cell line (b30 clone) has been examined as a potential in vitro system to study transplacental transport. At the light and electron microscope level, the cells were observed to form confluent monolayers on polycarbonate filters in approximately 5 days and morphologically resembled the typical human trophoblast. BeWo monolayers developed a modest transepithelial electrical resistance and a molecular size-dependent permeability to hydrophilic passive diffusion markers, fluorescein, and selected fluorescein-labeled dextrans. Linoleic acid permeation across BeWo monolayers was asymmetric, saturable, and inhibited by low temperature and excess competing fatty acid. Forskolin and 8-bromoadenosine 3',5' cyclic monophosphate treatments stimulated morphological changes in BeWo cultures and enhanced the asymmetric passage of linoleic acid across the BeWo monolayers while having minimal effects on passive permeability, affirming that the differentiation state of the cells can influence membrane transporters and transmonolayer permeability. The basic permeability properties of the BeWo monolayers suggest that the cells grown on permeable supports may be examined as a convenient in vitro system to evaluate some transplacental transport mechanisms. PMID- 9374644 TI - Niflumic acid differentially modulates two types of skeletal ryanodine-sensitive Ca(2+)-release channels. AB - The effects of niflumic acid on ryanodine receptors (RyRs) of frog skeletal muscle were studied by incorporating sarcoplasmic reticulum (SR) vesicles into planar lipid bilayers. Frog muscle had two distinct types of RyRs in the SR: one showed a bell-shaped channel activation curve against cytoplasmic Ca2+ or niflumic acid, and its mean open probability (Po) was increased by perchlorate at 20-30 mM (termed "alpha-like" RyR); the other showed a sigmoidal activation curve against Ca2+ or niflumic acid, with no effect on perchlorate (termed "beta-like" RyR). The unitary conductance and reversal potential of both channel types were unaffected after exposure to niflumic acid when clamped at 0 mV. When clamped at more positive potentials, the beta-like RyR channel rectified this, increasing the unitary current. Treatment with niflumic acid did not inhibit the response of both channels to Ca2+ release channel modulators such as caffeine, ryanodine, and ruthenium red. The different effects of niflumic acid on Po and the unitary current amplitude in both types of channels may be attributable to the lack or the presence of inactivation sites and/or distinct responses to agonists. PMID- 9374646 TI - Bradykinin-stimulated arachidonic acid release from MDCK cells is not protein kinase C dependent. AB - Bradykinin (BK)-induced release of arachidonic acid (AA) from Madin-Darby canine kidney (MDCK) D1 cells was investigated. Phorbol 12-myristate 13-acetate (PMA) caused a synergistic increase in BK- and A-23187-induced release of AA but alone had no effect on this release. Inhibition of protein kinase C (PKC) with bisindolmaleimide I (BIS) abolished the synergistic effects of PMA but did not affect AA release caused by BK or A-23187 alone. Downregulation of PKC with 100 nM PMA resulted in a reduction of AA release induced by BK or A-23187 addition, which corresponded to a decrease in cytoplasmic phospholipase A2 (cPLA2) activity as measured in cell extracts. Although Western blotting revealed no differences in cPLA2 expression as a result of PMA treatment, phosphorylation of the enzyme, as assessed by phosphoserine content, was significantly reduced in PKC-depleted cells. These results imply that, with PKC downregulation, subsequent BK stimulation results in a Ca(2+)-dependent translocation of a less phosphorylated, less active form of cPLA2. Any stimulation of PKC by BK addition did not appear as a significant event in onset responses leading to AA release. On the other hand, inhibition of the mitogen-activated protein kinase (MAPK) cascade with the MAPK kinase inhibitor, PD-98059, significantly decreased BK-induced release of AA, a finding that, with our other results, points to the existence of a PKC independent route for stimulation of MAPK and the propagation of onset responses. PMID- 9374647 TI - Oxygen sensitivity of mitochondrial metabolic state in isolated skeletal and cardiac myocytes. AB - In striated muscle the coupling of blood flow to changes in tissue metabolism is hypothesized to be dependent in part on release of vasodilating metabolic by products generated when mitochondrial metabolism becomes O2 limited. Cytochrome oxidase, the terminal step in oxidative phosphorylation, is half-maximally saturated at < 1 mmHg PO2 in isolated mitochondria. However, blood flow is regulated at tissue PO2 of approximately 20 mmHg. If the affinity of mitochondrial respiration for O2 were higher in vivo than in vitro, O2 limitation of mitochondrial metabolism near mean tissue levels could occur. In the present study the PO2 at which mitochondrial metabolism becomes inhibited (critical PO2) was measured for cardiac myocytes in suspension (1.1 +/- 0.15 mmHg) and single cells (1.0 +/- 0.22 and 1.25 +/- 0.22 mmHg in cardiac myocytes and rat spinotrapezius cells, respectively). These measurements are consistent with those from isolated mitochondria, indicating that vasodilators produced when oxidative phosphorylation becomes inhibited may be important for regulating blood flow only in highly glycolytic muscles or under conditions of severe O2 limitation. PMID- 9374648 TI - Dipeptide-induced Cl- secretion in proximal tubule cells. AB - During a survey of dipeptides that might be transported by the renal PEPT2 transporter in proximal tubule cells, we discovered that acidic dipeptides could stimulate transient secretory anion current and conductance increases in intact cell monolayers. The stimulatory effect of acidic dipeptides was observed in several proximal tubule cell lines that have been recently developed by immortalization of early proximal tubule primary cultures from the Wistar-Kyoto and spontaneously hypertensive rat strains and humans, suggesting that this phenomenon is a characteristic of proximal tubule cells. The electrical current induced in intact monolayers by Ala-Asp, a representative of these acidic dipeptides, must represent Cl- secretion rather than Na+ or H+ absorption, because 1) it was Na+ independent, 2) it showed a pH dependence different from that of the PEPT2 cotransporter, and 3) it correlated with an Ala-Asp-induced increase in Cl- conductance of the apical membrane in basolaterally amphotericin B-permeabilized monolayers. The secretory current could be inhibited by stilbene disulfonates, but not diphenylamine-2-carboxylates, suggesting a non-cystic fibrosis transmembrane conductance regulator type of Cl- conductance. The effect of Ala-Asp was dose dependent, with an apparent 50% effective concentration of approximately 1 mM. Ala-Asp also produced intracellular acidification, suggesting that acidic dipeptides are also substrates for an H(+)-peptide cotransporter. PMID- 9374650 TI - Intermediate endocrine-acinar pancreatic cells in duct ligation conditions. AB - When tissues were subjected to 24 h of duct ligation, intermediate pancreatic cells simultaneously displaying endocrine and exocrine phenotypes appeared. Immunocytochemistry by laser scanning confocal microscopy revealed the appearance of a large number of these cells coexpressing insulin and amylase. These cells were located within the islets of Langerhans as well as in the acinar parenchyma. They were also detected in a culture system of isolated pancreatic cells. With the use of immunoelectron microscopy, two types of secretory granules were identified in these cells. One was insulin immunoreactive, whereas the other, resembling zymogen granules, contained amylase. Occasionally, some small granules displayed a double labeling for both secretory proteins. Numerous crinophagic bodies and autophagosomes containing insulin and/or amylase were also present. In situ hybridization, applied with the specific probes, confirmed the presence of both insulin and amylase mRNAs in these cells. Because duct ligation is known to induce insulin cell proliferation, the present results confirm that endocrine acinar cells do appear in such condition and may represent intermediate steps in a transdifferentiating process. PMID- 9374649 TI - Antisense oligodeoxynucleotide to PKC-delta blocks alpha 1-adrenergic activation of Na-K-2Cl cotransport. AB - A role for protein kinase C (PKC)-delta and -zeta isotypes in alpha 1-adrenergic regulation of human tracheal epithelial Na-K-2Cl cotransport was studied with the use of isotype-specific PKC inhibitors and antisense oligodeoxy-nucleotides to PKC-delta or -zeta mRNA. Rottlerin, a PKC-delta inhibitor, blocked 72% of basolateral-to-apical, bumetanide-sensitive 36Cl flux in nystatin-permeabilized cell monolayers stimulated with methoxamine, an alpha 1-adrenergic agonist, with a 50% inhibitory concentration of 2.3 microM. Methoxamine increased PKC activity in cytosol and a particulate fraction; the response was insensitive to PKC-alpha and -beta II isotype-specific inhibitors, but was blocked by general PKC inhibitors and rottlerin. Rottlerin also inhibited methoxamine-induced PKC activity in immune complexes of PKC-delta, but not PKC-zeta. At the subcellular level, methoxamine selectively elevated cytosolic PKC-delta activity and particulate PKC-zeta activity. Pretreatment of cell monolayers with antisense oligodeoxynucleotide to PKC-delta for 48 h reduced the amount of whole cell and cytosolic PKC-delta, diminished whole cell and cytosolic PKC-delta activity, and blocked methoxamine-stimulated Na-K-2Cl cotransport. Sense oligodeoxynucleotide to PKC-delta and antisense oligodeoxynucleotide to PKC-zeta did not alter methoxamine-induced cotransport activity. These results demonstrate the selective activation of Na-K-2Cl cotransport by cytosolic PKC-delta. PMID- 9374651 TI - Steroid hormone-dependent expression of blocker-sensitive ENaCs in apical membranes of A6 epithelia. AB - Weak channel blocker-induced noise analysis was used to determine the way in which the steroids aldosterone and corticosterone stimulated apical membrane Na+ entry into the cells of tissue-cultured A6 epithelia. Among groups of tissues grown on a variety of substrates, in a variety of growth media, and with cells at passages 73-112, the steroids stimulated both amiloride-sensitive and amiloride insensitive Na+ transport as measured by short-circuit currents in chambers perfused with either growth medium or a Ringer solution. From baseline rates of blocker-sensitive short-circuit current between 2 and 7 microA/cm2, transport was stimulated about threefold in all groups of experiments. Single channel currents averaged near 0.3 pA (growth medium) and 0.5 pA (Ringer) and were decreased 6-20% from controls by steroid due to the expected decreases of fractional transcellular resistance. Irrespective of baseline transport rates, the steroids in all groups of tissues stimulated transport by increase of the density of blocker-sensitive epithelial Na+ channels (ENaCs). Channel open probability was the same in control and stimulated tissues, averaging approximately 0.3 in all groups of tissues. Accordingly, steroid-mediated increases of open channel density responsible for stimulation of Na+ transport are due to increases of the apical membrane pool of functional channels and not their open probability. PMID- 9374652 TI - Growth factor-mediated K+ channel activity associated with human myeloblastic ML 1 cell proliferation. AB - ML-1 cell proliferation is dependent on the presence of serum growth factors. Removing serum from the culture medium results in growth arrest and promotes differentiation. In this study, we found that a 4-aminopyridine-sensitive K+ channel was highly expressed in proliferating ML-1 cells and significantly diminished in G1-arrested ML-1 cells induced by serum deprivation but was restored within 30 min in these cells with addition of 10% fetal bovine serum (FBS) or 5 ng/ml epidermal growth factor (EGF). Intracellular adenosine 3',5' cyclic monophosphate (cAMP) levels, but not guanosine 3',5'-cyclic monophosphate, were significantly increased in serum-deprived cells stimulated by FBS or EGF, and the effects of FBS and EGF on the channel activation were mimicked by exogenous cAMP. In inside-out patches, K+ channel activity was significantly increased by the cAMP-dependent protein kinase catalytic subunit, whereas the effect of EGF on K+ channel activation was blocked by Rp-8-(4 chlorophenylthio)adenosine 3',5'-cyclic monophosphothioate. Together, our results demonstrate that serum growth factors stimulate K+ channel activity in proliferation of ML-1 cells through protein kinase-induced phosphorylation and suggest an important molecular mechanism for serum growth factor-stimulated mitogenesis in ML-1 cells. PMID- 9374653 TI - Modulation of cardiac Ca2+ channels by isoproterenol studied in transgenic mice with altered SR Ca2+ content. AB - Phospholamban (PLB) ablation is associated with enhanced sarcoplasmic reticulum (SR) Ca2+ uptake and attenuation of the cardiac contractile responses to beta adrenergic agonists. In the present study, we compared the effects of isoproterenol (Iso) on the Ca2+ currents (ICa) of ventricular myocytes isolated from wild-type (WT) and PLB knockout (PLB-KO) mice. Current density and voltage dependence of ICa were similar between WT and PLB-KO cells. However, ICa recorded from PLB-KO myocytes had significantly faster decay kinetics. Iso increased ICa amplitude in both groups in a dose-dependent manner (50% effective concentration, 57.1 nM). Iso did not alter the rate of ICa inactivation in WT cells but significantly prolonged the rate of inactivation in PLB-KO cells. When Ba2+ was used as the charge carrier, Iso slowed the decay of the current in both WT and PLB-KO cells. Depletion of SR Ca2+ by ryanodine also slowed the rate of inactivation of ICa, and subsequent application of Iso further reduced the inactivation rate of both groups. These results suggest that enhanced Ca2+ release from the SR offsets the slowing effects of beta-adrenergic receptor stimulation on the rate of inactivation of ICa. PMID- 9374654 TI - The mineralocorticoid aldosterone activates a proton conductance in cultured kidney cells. AB - The mineralocorticoid aldosterone is the most important hormone for the regulation of Na+ and K+ homeostasis in mammals and is thereby involved in the regulation of extracellular volume and blood pressure. Because aldosterone is a steroid hormone, the classical way of action involves transcription, translation, and protein synthesis. We previously reported a rapid, nongenomic, and Zn(2+) sensitive action of aldosterone on Na+/H+ exchange in renal epithelial [Madin Darby canine kidney (MDCK)] cells (M. Gekle, N. Golenhofen, H. Oberleithner, and S. Silbernagl. Proc. Natl. Acad. Sci. 93: 10500-10504, 1996). Here we show that, in the absence of Na+ (i.e., with inactive Na+/H+ exchange), aldosterone induces a membrane potential-dependent and Zn(2+)-sensitive cytoplasmic acidification in MDCK cells within 2-4 min. This aldosterone-induced activation of a proton conductance is insensitive to the inhibitor of the classical genomic pathway, spironolactone. Furthermore, the inhibitor of serine/threonine kinases and staurosporine, as well as the specific inhibitor of protein kinase C (PKC), calphostin C, prevented proton conductance activation. Activation of PKC by phorbol esters mimicked the effect of aldosterone. Furthermore, preincubation of the cells with pertussis toxin reduced the effect of aldosterone significantly. We propose a new nongenomic mechanism of action for aldosterone, independently of the intracellular type 1 mineralocorticoid receptor: G protein-dependent stimulation of PKC by aldosterone leads to the activation of a plasma membrane proton conductance that enhances the activity of Na+/H+ exchange. This rapid nongenomic effect could explain the observation that aldosterone may alter renal Na+ and K+ excretion within 5-10 min. PMID- 9374655 TI - Regulation of intracellular calcium in human esophageal smooth muscles. AB - We have investigated sources of Ca2+ contributing to excitation of human esophageal smooth muscle, using fura 2 to study cytosolic free Ca2+ concentration ([Ca2+]i) in dispersed cells and contraction of intact muscles. Acetylcholine (ACh) caused an initial peak rise of [Ca2+]i followed by a plateau accompanied by reversible contraction. Removal of extracellular Ca2+ or addition of dihydropyridine Ca2+ channel blockers reduced the plateau phase but did not prevent contraction. Caffeine also caused elevation of [Ca2+]i and blocked responses to ACh. Undershoots of [Ca2+]i were apparent after ACh or caffeine. Blockade of the sarcoplasmic reticular Ca(2+)-ATPase by cyclopiazonic acid (CPA) reduced the ACh-evoked increase of [Ca2+]i and abolished the undershoot, indicating involvement of Ca2+ stores. When contraction was studied in intact muscles, removal of Ca2+ or addition of nifedipine reduced, but did not abolish, carbachol (CCh)-induced contraction. Elevation of extracellular K+ caused contraction that was inhibited by nifedipine, although CCh still elicited contraction. CPA caused contraction and suppressed the CCh-induced contraction, whereas ryanodine reduced CCh-induced contraction. Our studies provide evidence that muscarinic excitation of human esophagus involves both release of Ca2+ from intracellular stores and influx of Ca2+. PMID- 9374656 TI - Effect of 17 days of bed rest on peak isometric force and unloaded shortening velocity of human soleus fibers. AB - The purpose of this study was to examine the effect of prolonged bed rest (BR) on the peak isometric force (P0) and unloaded shortening velocity (V0) of single Ca(2+)-activated muscle fibers. Soleus muscle biopsies were obtained from eight adult males before and after 17 days of 6 degrees head-down BR. Chemically permeabilized single fiber segments were mounted between a force transducer and position motor, activated with saturating levels of Ca2+, and subjected to slack length steps. V0 was determined by plotting the time for force redevelopment vs. the slack step distance. Gel electrophoresis revealed that 96% of the pre- and 87% of the post-BR fibers studied expressed only the slow type I myosin heavy chain isoform. Fibers with diameter > 100 microns made up only 14% of this post BR type I population compared with 33% of the pre-BR type I population. Consequently, the post-BR type I fibers (n = 147) were, on average, 5% smaller in diameter than the pre-BR type I fibers (n = 218) and produced 13% less absolute P0. BR had no overall effect on P0 per fiber cross-sectional area (P0/CSA), even though half of the subjects displayed a decline of 9-12% in P0/CSA after BR. Type I fiber V0 increased by an average of 34% with BR. Although the ratio of myosin light chain 3 to myosin light chain 2 also rose with BR, there was no correlation between this ratio and V0 for either the pre- or post-BR fibers. In separate fibers obtained from the original biopsies, quantitative electron microscopy revealed a 20-24% decrease in thin filament density, with no change in thick filament density. These results raise the possibility that alterations in the geometric relationships between thin and thick filaments may be at least partially responsible for the elevated V0 of the post-BR type I fibers. PMID- 9374657 TI - Influence of bafilomycin A1 on pHi responses in cultured rabbit nonpigmented ciliary epithelium. AB - Aqueous humor secretion is in part linked to HCO3- transport by nonpigmented ciliary epithelium (NPE) cells. During this process, the cells must maintain stable cytoplasmic pH (pHi). Because a recent report suggests that NPE cells have a plasma membrane-localized vacuolar H(+)-ATPase, the present study was conducted to examine whether vacuolar H(+)-ATPase contributes to pHi regulation in a rabbit NPE cell line. Western blot confirmed vacuolar H(+)-ATPase expression as judged by H(+)-ATPase 31-kDa immunoreactive polypeptide in both cultured NPE and native ciliary epithelium. pHi was measured using 2',7'-bis(carboxyethyl)-5(6) carboxyfluorescein (BCECF). Exposing cultured NPE to K(+)-rich solution caused a pHi increase we interpret as depolarization-induced alkalinization. Alkalinization was also caused by ouabain or BaCl2. Bafilomycin A1 (0.1 microM; an inhibitor of vacuolar H(+)-ATPase) inhibited the pHi increase caused by high K+. The pHi increase was also inhibited by angiotensin II and the metabolic uncoupler carbonyl cyanide m-chlorophenylhydazone but not by ZnCl2, 4-acetamido 4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS), 4,4'-diisothiocyanostilbene 2,2'-disulfonic acid (DIDS), omeprazole, low-Cl- medium, HCO3(-)-free medium, or Na(+)-free medium. Bafilomycin A1 slowed the pHi increase after an NH4Cl (10 mM) prepulse. However, no detectable pHi change was observed in cells exposed to bafilomycin A1 under control conditions. These studies suggest that vacuolar H(+) ATPase is activated by cytoplasmic acidification and by reduction of the proton electrochemical gradient across the plasma membrane. We speculate that the mechanism might contribute to maintenance of acid-base balance in NPE. PMID- 9374658 TI - Retinoids regulate tight junctional resistance of cultured human cervical cells. AB - The objective of the study was to determine the effect of retinoids on paracellular resistance across the cervical epithelium and the mechanisms involved. The experimental model was cultures of human CaSki cells on filters, which retain phenotypic characteristics of the endocervical epithelium. End points for paracellular resistance were measurements of transepithelial electrical resistance and fluxes of pyranine (a trisulfonic acid that traverses the epithelium via the intercellular space). Paracellular resistance was significantly increased in cells grown in retinoid-free medium; the effect could be blocked and reversed with all-trans-retinoic acid (tRA) and with agonists of RAR and RXR receptors but only partially with retinol. The effect of tRA was dose dependent and saturable, with a 50% effective concentration of 0.8 nM. The increases in paracellular resistance induced by vitamin A deficiency required longer incubation in retinoid-free medium than decreases in resistance induced by retinoic acid. tRA had only a minimal effect on paracellular resistance in cells maintained in regular medium. Retinoid-free medium increased and tRA decreased the relative cation mobility across CaSki cultures. Also the effects of tRA were nonadditive to those of cytochalasin D (which decreases tight junctional resistance) and additive to those of ionomycin (which decreases the resistance of the lateral intercellular space), suggesting that tRA modulates tight junctional resistance. It is concluded that vitamin A determines the degree of paracellular resistance across cervical cells by a mechanism that involves modulation of tight junctional resistance. PMID- 9374659 TI - Long-term regulation of contractility and calcium current in smooth muscle. AB - Longitudinal smooth muscle strips from guinea pig ileum were cultured in vitro for 5 days, and the relationship between extracellular Ca2+ and force in high-K+ medium was evaluated. In strips cultured with 10% fetal calf serum (FCS), this relationship was shifted to the right (50% effective concentration changed by 2-3 mM) compared with strips cultured without FCS. The shift was prevented by inclusion of verapamil (1 microM) during culture and mimicked by ionomycin in the absence of FCS. The intracellular Ca2+ concentration ([Ca2+]i) during stimulation with high-K+ solution or carbachol was reduced after culture with FCS, whereas the [Ca2+]i-force relationship was unaffected. Cells were isolated from cultured strips, and whole cell voltage-clamp experiments were performed. Maximum inward Ca2+ current (10 mM Ba2+), normalized to cell capacitance, was almost three times smaller in cells isolated from strips cultured with FCS. Culture with 1 microM verapamil prevented this reduction. These results suggest that increased [Ca2+]i during culture downregulates Ca2+ current density, with associated effects on contractility. PMID- 9374660 TI - Ca2+ dependence and pharmacology of large-conductance K+ channels in nonlabor and labor human uterine myocytes. AB - Two populations, Ca(2+)-dependent (BKCa) and Ca(2+)-independent K+ (BK) channels of large conductance were identified in inside-out patches of nonlabor and labor freshly dispersed human pregnant myometrial cells, respectively. Cell-attached recordings from nonlabor myometrial cells frequently displayed BKCa channel openings characterized by a relatively low open-state probability, whereas similar recordings from labor tissue displayed either no channel openings or consistently high levels of channel activity that often exhibited clear, oscillatory activity. In inside-out patch recordings, Ba2+ (2-10 mM), 4 aminopyridine (0.1-1 mM), and Shaker B inactivating peptide ("ball peptide") blocked the BKCa channel but were much less effective on BK channels. Application of tetraethylammonium to inside-out membrane patches reduced unitary current amplitude of BKCa and BK channels, with dissociation constants of 46 mM and 53 microM, respectively. Tetraethylammonium applied to outside-out patches decreased the unitary conductance of BKCa and BK channels, with dissociation constants of 423 and 395 microM, respectively. These results demonstrate that the properties of human myometrial large-conductance K+ channels in myocytes isolated from laboring patients are significantly different from those isolated from nonlaboring patients. PMID- 9374662 TI - Human cytomegalovirus infection enhances osmotic stimulation of Na+/H+ exchange in human fibroblasts. AB - Infection with human cytomegalovirus (HCMV) causes an enlargement (cytomegaly) of human fibroblasts (MRC-5). As a first step toward determining whether solute uptake, mediated in part by Na+/H+ exchange, is responsible for the development of cytomegaly, we studied the effects of HCMV infection on intracellular pH (pHi) regulation (nominal CO2/ HCO3- concn = 0) by comparing cytomegalic cells with mock-infected cells. Seventy-two hours after HCMV infection of MRC-5 cells we observed the following changes relative to mock-infected cells: resting pHi is 0.1-0.2 pH unit more alkaline; the intrinsic buffering power of the cytoplasm was reduced by approximately 40-50%; acid-loading H(+)-equivalent fluxes were reduced; and there were alterations of Na+/H+ exchanger (NHE) properties, including an alkaline shift of the pHi dependence of activity, a reduction of the apparent affinity for extracellular Na+, and an increase of the apparent maximum velocity and a large increase in stimulation by a hyperosmotic challenge. These results indicate that HCMV infection exerts a profound effect on functional properties of the NHE, on acid-loading mechanisms, and on intrinsic cellular buffering power. These effects are consistent with a role for the NHE in the development of cytomegaly. PMID- 9374661 TI - Glycolysis inhibition by palmitate in renal cells cultured in a two-chamber system. AB - A major shortcoming of renal proximal tubular cells (RPTC) in culture is the gradual modification of their energy metabolism from the oxidative type to the glycolytic type. To test the possible reduction of glycolysis by naturally occurring long-chain fatty acids, RPTC were cultured in a two-chamber system, with albumin-bound palmitate (0.4 mM) added to the basolateral chamber after confluency. Twenty-four hours of contact with palmitate decreased glycolysis by 38% provided that carnitine was present; lactate production was decreased by 38%, and the decrease in glycolysis resulted from a similar decrease of basolateral and apical net uptake of glucose. In contrast to the previously described effect of the nonphysiological oxidative substrate heptanoate, palmitate promoted a long term decrease in lactate production and sustained excellent cellular growth. After 4 days of contact, decreased glycolysis was maintained even in the absence of carnitine and resulted from a decrease of basolateral uptake only, suggestive of long-term regulation different from the earlier effects. Thus, although cultured RPTC lost their oxidative phenotype, they exhibited a type of regulation (Randle effect) that is found in the oxidative-type but not in the glycolytic type tissues, therefore unmasking a regulative capacity barely detectable in fresh RPTC. Low PO2 (50 mmHg in the apical chamber) could be a major cause of elevated glycolysis and could hinder the effects of palmitate. PMID- 9374663 TI - Prostaglandin H synthase: protein synthesis-independent regulation in bovine aortic endothelial cells. AB - The objective of the present study was to examine whether prostaglandin H synthase (PGHS) can be regulated by pathways independent of de novo synthesis of PGHS. Incubation of bovine aortic endothelial cells (BAEC) for as short as 5 min with NaF (40 mM) resulted in a 60% increase in PGHS activity. PGHS activity induced by NaF was unaffected by either 10 microM cycloheximide or 1 microM actinomycin D. Aspirin (25 microM) completely inhibited resting PGHS activity, and NaF did not induce further stimulation. NS-398 (500 nM), a specific PGHS-2 inhibitor, was ineffective. Basic fibroblast growth factor (bFGF) induced a significant increase in PGHS activity within 30 min and was insensitive to cycloheximide. The levels of PGHS-1 and PGHS-2 proteins, as measured by Western blots, were not affected by NaF or bFGF. The tyrosine kinase inhibitor genistein attenuated PGHS activity that was induced by NaF and bFGF, whereas the tyrosine phosphatase inhibitor, sodium orthovanadate, augmented these responses. The G protein activators 5'-guanylyl imidodiphosphate and guanosine 5'-O-(3 thiotriphosphate) inhibited both resting and NaF-induced PGHS activities. These results suggest-that, in BAEC, PGHS-1 activity can be regulated by tyrosine kinase and/or G proteins, independently of de novo protein synthesis. PMID- 9374664 TI - Site-specific thrombin receptor antibodies inhibit Ca2+ signaling and increased endothelial permeability. AB - Thrombin receptor is activated by thrombin-mediated cleavage of the receptor's NH2 terminus between Arg-41 and Ser-42, generating a new NH2 terminus that functions as a "tethered ligand" by binding to sites on the receptor. We prepared antibodies (Abs) directed against specific receptor domains to study the tethered ligand-receptor interactions required for signaling the increase in endothelial permeability to albumin. We used polyclonal Abs directed against the peptide sequences corresponding to the extracellular NH2 terminus [residues 70-99 (AbDD) and 1-160 (AbEE)] and extracellular loops 1 and 2 [residues 161-178 (AbL1) and 244-265 (AbL2)] of the seven-transmembrane thrombin receptor. Receptor activation was determined by measuring changes in cytosolic Ca2+ concentration ([Ca2+]i) in human dermal microvascular endothelial cells (HMEC) loaded with Ca(2+)-sensitive fura 2-acetoxymethyl ester dye. The transendothelial 125I-labeled albumin clearance rate (a measure of endothelial permeability) was determined across the confluent HMEC monolayers. AbEE (300 micrograms/ml), directed against the entire extracellular NH2-terminal extension, inhibited the thrombin-induced increases in [Ca2+]i and the endothelial 125I-albumin clearance rate (> 90% reduction in both responses). AbDD (300 micrograms/ml), directed against a sequence within the NH2 terminal extension, inhibited 70% of the thrombin-induced increase in [Ca2+]i and 60% of the increased 125I-albumin clearance rate. AbL2 (300 micrograms/ml) inhibited these responses by 70 and 80%, respectively. However, AbL1 (300 micrograms/ml) had no effect on either response. We conclude that NH2-terminal extension and loop 2 are critical sites for thrombin receptor activation in endothelial cells and thus lead to increased [Ca2+]i and transendothelial permeability to albumin. PMID- 9374665 TI - Regulation of endothelin-1 gene expression by cell shape and the microfilament network in vascular endothelium. AB - Endothelial synthesis and release of endothelin-1 (ET-1) are exquisitely regulated by external shear and strain. We tested the hypothesis that manipulation of endothelial cell shape can regulate ET-1 gene expression. Treatment of bovine aortic endothelial cell (BAEC) monolayers with cytochalasin D disrupted F-actin and induced cell retraction and rounding, in parallel with time and dose-dependent specific decreases in ET-1 mRNA levels. Treatments with forskolin, phorbol 12-myristate 13-acetate, staurosporine, and genistein also induced cell shape change and decreased F-actin staining and ET-1 mRNA levels. BAEC plated onto nonadhesive petri dishes coated with decreasing concentrations of synthetic RGD polymer showed RGD dose-dependent decreases in cell spreading and in F-actin microfilament elaboration. These changes were specifically accompanied by decreases in ET-1 peptide secretion (60%) and, via posttranscriptional mechanisms, ET-1 mRNA (94%) and were not due to decreased cell-cell contact. We conclude that the shape and microfilament network of endothelial cells are potent posttranscriptional regulators of ET-1 gene expression. PMID- 9374666 TI - Elementary events of agonist-induced Ca2+ release in vascular endothelial cells. AB - The subcellular spatial and temporal organization of agonist-induced Ca2+ signals was investigated in single cultured vascular endothelial cells. Extracellular application of ATP initiated a rapid increase of intracellular Ca2+ concentration ([Ca2+]i) in peripheral cytoplasmic processes from where activation propagated as a [Ca2+]i wave toward the central regions of the cell. The average propagation velocity of the [Ca2+]i wave in the peripheral processes was 20-60 microns/s, whereas in the central region the wave propagated at < 10 microns/s. The time course of the recovery of [Ca2+]i depended on the cell geometry. In the peripheral processes (i.e., regions with a high surface-to-volume ratio) [Ca2+]i declined monotonically, whereas in the central region [Ca2+]i decreased in an oscillatory fashion. Propagating [Ca2+]i waves were preceded by small, highly localized [Ca2+]i transients originating from 1- to 3-micron-wide regions. The average amplitude of these elementary events of Ca2+ release was 23 nM, and the underlying flux of Ca2+ amounted to approximately 1-2 x 10(-18) mol/s or approximately 0.3 pA, consistent with a Ca2+ flux through a single or small number of endoplasmic reticulum Ca(2+)-release channels. PMID- 9374668 TI - Determination of local brain glucose level with [14C]methylglucose: effects of glucose supply and demand. AB - Methylglucose can be used to assay brain glucose levels because the equilibrium brain-to-plasma distribution ratio for methylglucose (Ce*/Cp*) is quantitatively related to brain (Ce) and plasma (Cp) glucose contents. The relationship between Ce and Ce*/Cp* predicted by Michaelis-Menten kinetics has been experimentally confirmed when glucose utilization rate (CMRGlc) is maintained at normal, resting levels and Cp is varied in conscious rats. Theoretically, however, Ce and Ce*/Cp* should change when CMRGlc is altered and Cp is held constant; their relationship in such conditions was, therefore, examined experimentally. Drugs were applied topically to brains of conscious rats with fixed levels of Cp to produce focal alterations in CMRGlc, and Ce and Ce*/Cp* were measured. Plots of Ce as a function of Ce*/Cp* for each Cp produced straight lines; their slopes decreased as Cp increased. The results confirm that a single theoretical framework describes the relationship between Ce and Ce*/Cp* as either glucose supply or demand is altered over a wide range; they also validate the use of methylglucose to estimate local Ce under abnormal conditions. PMID- 9374667 TI - Role of hepatic alpha- and beta-adrenergic receptor stimulation on hepatic glucose production during heavy exercise. AB - The role of catecholamines in the control of hepatic glucose production was studied during heavy exercise in dogs, using a technique to selectively block hepatic alpha- and beta-adrenergic receptors. Surgery was done > 16 days before the study, at which time catheters were implanted in the carotid artery, portal vein, and hepatic vein for sampling and the portal vein and vena cava for infusions. In addition, flow probes were implanted on the portal vein and hepatic artery. Each study consisted of a 100-min equilibration, a 30-min basal, a 20-min heavy exercise (approximately 85% of maximum heart rate), a 30-min recovery, and a 30-min adrenergic blockade test period. Either saline (control; n = 7) or alpha (phentolamine)- and beta (propranolol)-adrenergic blockers (Blk; n = 6) were infused in the portal vein. In both groups, epinephrine (Epi) and norepinephrine (NE) were infused in the portal vein during the blockade test period to create supraphysiological levels at the liver. Isotope ([3-3H]glucose) dilution and arteriovenous differences were used to assess hepatic function. Arterial Epi, NE, glucagon, and insulin levels were similar during exercise in both groups. Endogenous glucose production (Ra) rose similarly during exercise to 7.9 +/- 1.2 and 7.5 +/- 2.0 mg.kg-1.min-1 in control and Blk groups at time = 20 min. Net hepatic glucose output also rose to a similar rate in control and Blk groups with exercise. During the blockade test period, arterial plasma glucose and Ra rose to 164 +/- 5 mg/dl and 12.0 +/- 1.4 mg.kg-1.min-1, respectively, but were essentially unchanged in Blk. The attenuated response to catecholamine infusion in Blk substantiates the effectiveness of the hepatic adrenergic blockade. In conclusion, these results show that direct hepatic adrenergic stimulation does not participate in the increase in Ra, even during the exaggerated sympathetic response to heavy exercise. PMID- 9374669 TI - Stimulation of Ca2+ influx in alpha T3-1 gonadotrophs via the cAMP/PKA signaling system. AB - To investigate the regulation of free cytosolic calcium concentration ([Ca2+]i) by the adenosine 3',5'-cyclic monophosphate (cAMP) signaling system in clonal gonadotrophs, microfluorimetric recordings were made in single indo 1-loaded alpha T3-1 cells. Forskolin, 8-bromoadenosine 3',5'-cyclic monophosphate, or a low concentration (100 pM) of the hypothalamic factor pituitary adenylate cyclase activating polypeptide (PACAP) stimulated Ca2+ step responses or repetitive Ca2+ transients, which were blocked by the removal of extracellular Ca2+ by the dihydropyridine (DHP) (+)PN 200-110 or by preincubation with the protein kinase A (PKA) antagonist H-89 (10 microM). Thus activation of the cAMP/PKA system in alpha T3-1 gonadotrophs stimulates Ca2+ influx through DHP-sensitive (L-type) Ca2+ channels. In contrast, high PACAP concentrations (100 nM) stimulated biphasic Ca2+ spike-plateau responses. The Ca2+ spike was independent of extracellular Ca2+, and similar responses were observed by microperfusion of individual cells with D-myo-inositol 1,4,5-trisphosphate, suggesting the involvement of the phospholipase C (PLC) signaling pathway. The Ca2+ plateau depended on Ca2+ influx, was blocked by (+)PN 200-110, but was only partially blocked by H-89 pretreatment. In conclusion, PACAP stimulates [Ca2+]i increases in alpha T3-1 gonadotrophs through both the PLC and adenylate cyclase signaling pathways. Furthermore, this is the first clear demonstration that the cAMP/PKA system can mediate changes in [Ca2+]i in gonadotroph-like cells. PMID- 9374670 TI - Rat amylin-(8-37) enhances insulin action and alters lipid metabolism in normal and insulin-resistant rats. AB - To clarify roles of amylin, we investigated metabolic responses to rat amylin-(8 37), a specific amylin antagonist, in normal and insulin-resistant, human growth hormone (hGH)-infused rats. Fasting conscious rats were infused with saline or hGH, each with and without amylin-(8-37) (0.125 mumol/h), over 5.75 h. At 3.75 h, a hyperinsulinemic (100 mU/l) clamp with bolus 2-deoxy-D-[3H]glucose and [14C]glucose was started. hGH infusion led to prompt (2- to 3-fold) basal hyperamylinemia (P < 0.02) and hyperinsulinemia. Amylin-(8-37) reduced plasma insulin (P < 0.001) and enhanced several measures of whole body and muscle insulin sensitivity (P < 0.05) in both saline- and hGH-infused rats. Amylin-(8 37) corrected hGH-induced liver insulin resistance, increased basal plasma triglycerides and lowered plasma nonesterified fatty acids in both groups, and reduced muscle triglyceride and total long-chain acyl-CoA content in saline treated rats (P < 0.05). In isolated soleus muscle, amylin-(8-37) blocked amylin induced inhibition of glycogen synthesis but had no effect in the absence of amylin. Thus 1) hyperamylinemia accompanies insulin resistance induced by hGH infusion; 2) amylin-(8-37) increases whole body and muscle insulin sensitivity and consistently reduces basal insulin levels in normal and hGH-induced insulin resistant rats; and 3) amylin-(8-37) elicits a significant alteration of in vivo lipid metabolism. These findings support a role of amylin in modulating insulin action and suggest that this could be mediated by effects on lipid metabolism. PMID- 9374671 TI - Inhibition of glycogenolysis enhances gluconeogenic precursor uptake by the liver of conscious dogs. AB - We investigated the effect of inhibiting glycogenolysis on gluconeogenesis in 18 h-fasted conscious dogs with the use of intragastric administration of BAY R 3401, a glycogen phosphorylase inhibitor. Isotopic ([3-3H]glucose and [U 14C]alanine) and arteriovenous difference methods were used to assess glucose metabolism. Each study consisted of a 100-min equilibration, a 40-min control, and two 90-min test periods. Endogenous insulin and glucagon secretions were inhibited with somatostatin (0.8 microgram.kg-1.min-1), and the two hormones were replaced intraportally (insulin: 0.25 mU.kg-1.min-1; glucagon: 0.6 ng.kg-1.min 1). Drug (10 mg/kg) or placebo was given after the control period. Insulin and glucagon were kept at basal levels in the first test period, after which glucagon infusion was increased to 2.4 ng.kg-1.min-1; BAY R 3401 decreased tracer determined endogenous glucose production [rate of glucose production (Ra): 14 +/- 1 to 7 +/- 1 mumol.kg-1.min-1] and net hepatic glucose output (11 +/- 1 to 3 +/- 2 mumol.kg-1.min-1) during test 1. It increased the net hepatic uptake of gluconeogenic substrates from 9.0 +/- 2.0 to 11.6 +/- 0.6 mumol.kg-1.min-1. Basal glycogenolysis was decreased by drug (9.1 +/- 0.7 to 1.5 +/- 0.2 mumol glucosyl U.kg-1.min-1). Placebo had no effect on Ra or the uptake of gluconeogenic precursors by the liver. The rise in glucagon increased Ra by 22 +/- 3 and by 8 +/- 2 mumol.kg-1.min-1 (at 10 min) in placebo and drug, respectively. The rise in glucagon caused little change in the net hepatic uptake (mumol.kg-1.min-1) of gluconeogenic substrates in placebo (8.2 +/- 0.6 to 9.0 +/- 1.0) but increased it markedly (11.6 +/- 0.6 to 15.4 +/- 1.0) in drug. Glucagon increased glycogenolysis by 22.1 +/- 2.5 and by 7.8 +/- 1.6 mumol.kg-1.min-1 in placebo and drug, respectively. The amount of glycogen (mumol glucosyl U/kg) synthesized from gluconeogenic carbon was four times higher in drug (48.6 +/- 9.7) than in placebo (11.3 +/- 1.7). We conclude that BAY R 3401 caused a marked reduction in basal and glucagon-stimulated glycogenolysis. As a result of these changes, there was an increase in the net hepatic uptake of gluconeogenic precursors and in glycogen synthesis. PMID- 9374672 TI - Parathyroid Ca(2+)-conducting currents are modulated by muscarinic receptor agonists and antagonists. AB - Parathyroid cells express Ca(2+)-conducting cation currents, which are activated by raising the extracellular Ca2+ concentration ([Ca2+]o) and blocked by dihydropyridines. We found that acetylcholine (ACh) inhibited these currents in a reversible, dose-dependent manner (50% inhibitory concentration approximately equal to 10(-8) M). The inhibitory effects could be mimicked by the agonist (+) muscarine. The effects of ACh were blunted by the antagonist atropine and reversed by removing ATP from the pipette solution (+)-Muscarine enhanced the adenosine 3',5'-cyclic monophosphate (cAMP) production by 30% but had no effect on inositol phosphate accumulation in parathyroid cells. Oligonucleotide primers, based on sequences of known muscarinic receptors (M1-M5), were used in reverse transcriptase-polymerase chain reaction (RT-PCR) to amplify receptor cDNA from parathyroid poly (A)+ RNA. RT-PCR products displayed > 90% nucleotide sequence identity to human M2- and M4-receptor cDNAs. Expression of M2-receptor protein was further confirmed by immunoblotting and immunocytochemistry. Thus parathyroid cells express muscarinic receptors of M2 and possibly M4 subtypes. These receptors may couple to dihydropyridine-sensitive, cation-selective currents through the activation of adenylate cyclase and ATP-dependent pathways in these cells. PMID- 9374673 TI - Existence of two nonlinear elimination mechanisms for hepatocyte growth factor in rats. AB - Nonlinearity in the overall elimination of hepatocyte growth factor (HGF) was examined in rats. After intravenous administration, the plasma clearance (CLplasma) of HGF exhibited a dose-dependent biphasic reduction with high- and low-affinity components. If we consider our previous finding that both receptor mediated endocytosis (RME) and a low-affinity uptake mechanism, probably mediated by heparan sulfate proteoglycan (HSPG), in the liver are major HGF clearance mechanisms, it may be that saturation of CLplasma at lower and higher doses represents saturation of RME and HSPG-mediated uptake, respectively. At an HGF dose (1.46 nmol/kg), which completely saturates the high-affinity component, CLplasma was almost completely reduced when HGF was premixed with heparin. However, CLplasma was reduced by heparin to, at most, one-fifth that after HGF alone in a dose near the linear range (3.66 pmol/kg). Saturation of CLplasma for HGF premixed with heparin was monophasic and nonlinear only at the lowest HGF doses. In vitro, high-affinity binding of [35S]heparin to HGF was found, showing that one HGF molecule binds to the penta- or hexasaccharide unit. Because mitogenic activity of HGF has been reported in the presence of heparin, these results suggest that heparin mainly inhibits low-affinity HGF uptake by complexing with HGF, whereas its effect on RME is relatively minor. PMID- 9374674 TI - Albumin and fibrinogen syntheses increase while muscle protein synthesis decreases in head-injured patients. AB - The effect of trauma on protein metabolism was investigated in the whole body, muscle, and liver in severely head-injured patients presenting an acute inflammatory response by comparison to fed control subjects receiving a similar diet. Nonoxidative leucine disposal (an index of whole body protein synthesis) and muscle, albumin, and fibrinogen synthesis were determined by means of a primed, continuous infusion of L-[1-13C]leucine. Nonoxidative leucine disposal increased by 28% in the patients (P < 0.02). Fractional muscle protein synthesis rate decreased by 50% (P < 0.01) after injury. Fractional and absolute fibrinogen synthesis rates were multiplied by two and nine, respectively, after injury (P < 0.001). Albumin levels were lower in patients (25.2 +/- 1.2 g/l, means +/- SE) than in controls (33.7 +/- 1.2 g/l, P < 0.001). However, fractional albumin synthesis rates were increased by 60% in patients (11.4 +/- 1.0%/day) compared with controls (7.3 +/- 0.4%/day, P < 0.01). Therefore, 1) head trauma induces opposite and large changes of protein synthesis in muscle and acute-phase hepatic proteins, probably mediated by cytokines, glucocorticoids, and other stress hormones, and 2) in these patients, hypoalbuminemia is not due to a depressed albumin synthesis. PMID- 9374675 TI - Role of the kidney in human leptin metabolism. AB - To assess the role of the human kidney in leptin metabolism, we measured renal leptin net balance and urinary leptin excretion in 16 normal postabsorptive volunteers with varying degrees of obesity. Arterial leptin concentrations (11.6 +/- 2.7 ng/ml) significantly exceeded renal vein concentrations (10.3 +/- 2.5 ng/ml, P < 0.001). Renal leptin fractional extraction averaged 13.1 +/- 1.1%, and renal leptin net balance (uptake) averaged 1,070 +/- 253 ng/min. Lineweaver-Burk analysis indicated that renal leptin uptake followed saturation kinetics with an apparent Michaelis-Menten constant of 10.9 ng/ml and maximal velocity of 1,730 ng/min. Leptin was generally undetectable in urine. Using literature values for systemic leptin clearance, we calculated that renal leptin uptake could account for approximately 80% of all leptin removal from plasma. These data indicate that the human kidney plays a substantial role in leptin removal from plasma by taking up and degrading the peptide. PMID- 9374676 TI - In humans at least 75% of insulin secretion arises from punctuated insulin secretory bursts. AB - Detection of insulin secretory bursts in peripheral blood is hampered by hepatic insulin extraction, dilution in the systemic insulin pool, and time-delayed damping of secretory burst amplitude. Previous studies in dogs in vivo and other experiments in vitro have shown that approximately 70% of all insulin is released within distinct insulin secretory bursts. To establish a method for detection and quantification of pulsatile insulin release in humans on the basis of peripheral insulin concentration measurements, we used a high-sensitivity, -specificity, and -precision insulin enzyme-linked immunosorbent assay (ELISA) and optimized an established deconvolution methodology to quantify the frequency, mass, and amplitude of insulin secretory bursts as well as to estimate the relative contribution of pulsatile insulin release to overall insulin secretion. By use of minutely sampled serum insulin concentrations measured by a highly sensitive insulin ELISA and insulin kinetics of 2.8 min (first half-life), 5.0 min (second half-life), and a fractional slow component of 0.28, the deconvolved insulin secretion rates in 20 healthy subjects during glucose infusion (4.5 mg.kg-1.min 1) could be resolved into a series (4.7 +/- 0.1 min/pulse) of approximately symmetric insulin secretory bursts with a mean mass of 87 +/- 12 pmol.l-1 pulse-1 and a mean amplitude (maximal release rate) of 35 +/- 4.7 pmol.l-1.min-1. The relative contribution of pulsatile to overall insulin secretion was 75 +/- 1.6% (range 59-85%). We conclude that in vivo insulin secretion in humans during nominal glucose stimulation consists of a series of punctuated insulin secretory bursts accounting for > or = 75% of total insulin secretion. PMID- 9374677 TI - Reversal of chronic alterations of skeletal muscle protein kinase C from fat-fed rats by BRL-49653. AB - We have recently shown that the reduction in insulin sensitivity of rats fed a high-fat diet is associated with the translocation of the novel protein kinase C epsilon (nPKC epsilon) from cytosolic to particulate fractions in red skeletal muscle and also the downregulation of cytosolic nPKC theta. Here we have further investigated the link between insulin resistance and PKC by assessing the effects of the thiazolidinedione insulin-sensitizer BRL-49653 on PKC isoenzymes in muscle. BRL-49653 increased the recovery of nPKC isoenzymes in cytosolic fractions of red muscle from fat-fed rats, reducing their apparent activation and/or downregulation, whereas PKC in control rats was unaffected. Because BRL 49653 also improves insulin-stimulated glucose uptake in fat-fed rats and reduces muscle lipid storage, especially diglyceride content, these results strengthen the association between lipid availability, nPKC activation, and skeletal muscle insulin resistance and support the hypothesis that chronic activation of nPKC isoenzymes is involved in the generation of muscle insulin resistance in fat-fed rats. PMID- 9374678 TI - Role of cAMP and calcium influx in endothelin-1-induced ANP release in rat cardiomyocytes. AB - The mechanism of endothelin-1 (ET-1)-induced atrial natriuretic peptide (ANP) release was studied in neonatal rat ventricular cardiomyocytes. These cells expressed a single high-affinity class of ETA receptor (dissociation constant = 54 +/- 18 pM, n = 3), but no ETB receptors. Incubation of cardiomyocytes with ET 1 led to concentration-dependent ANP release and prostacyclin production. ET-1 induced ANP release was affected by neither protein kinase C (PKC) inhibition or downregulation nor by cyclooxygenase inhibition, indicating that ET-1-stimulated ANP secretion is not a PKC-mediated, prostaglandin-dependent process. Furthermore, ET-1 significantly stimulated adenosine 3',5'-cyclic monophosphate (cAMP) production and increased cytosolic calcium concentration in these preparations. Both ET-1-induced calcium influx and ANP release were decreased by the cAMP antagonist Rp-cAMPS, the Rp diastereoisomer of cAMP. Moreover, ET-1 induced ANP secretion was strongly inhibited in the presence of nifedipine as well as in the absence of extracellular calcium. Thus our results suggest that ET 1 stimulates ANP release in ventricular cardiomyocytes via an ETA receptor mediated pathway involving cAMP formation and activation of a nifedipine sensitive calcium channel. PMID- 9374679 TI - Growth hormone induces detergent insolubility of GH receptors in IM-9 cells. AB - In this study, we examined human growth hormone (hGH)-induced changes in nonionic detergent solubility characteristics of its receptor (hGHR). Exposure of IM-9 cells to hGH caused a time- and concentration-dependent loss of immunoblottable detergent-extractable hGHRs and a corresponding accumulation of receptors in a detergent-insoluble pool. At 37 degrees C, the loss of detergent-soluble and the accumulation of detergent-insoluble hGHRs both preceded hGH-induced loss of total cell hGHRs. The detergent-insoluble receptor pool was progressively enriched in an apparent disulfide-linked form of the hGHR. Exposure to hGH at 4 degrees C allowed hGH-induced hGHR disulfide linkage but did not promote changes in receptor detergent solubility, indicating that hGHR detergent insolubility cannot be explained solely by the formation of that linkage. Experiments carried out with hGH at 20 degrees C and with the phorbol ester, phorbol-12,13-myristate acetate, at 37 degrees C indicated that loss of detergent-soluble hGHRs can be uncoupled from accumulation of detergent-insoluble receptors. From these data, we envision at least two related, but separable, trafficking pathways taken by hGHRs after their surface interaction with hGH:1) ligand-mediated endocytosis and degradation (accounting for only some of the receptors lost from the detergent soluble fraction) and 2) ligand-mediated accumulation in a detergent-insoluble subcellular fraction (arising largely from receptors redistributed from the detergent-soluble fraction). PMID- 9374680 TI - Interleukin-1 beta inhibits phospholipase C and insulin secretion at sites apart from KATP channel. AB - Although interleukin-1 beta (IL-1 beta) reduces pancreatic islet content of ATP and GTP, the distal events that mediate its inhibitory effects on insulin secretion remain poorly understood. Herein, the activation of phospholipase C (PLC) was quantified during islet perifusions. An 18-h exposure to IL-1 beta (100 pM) totally vitiated activation of PLC induced by glucose, an effect that requires ATP and GTP and closure of the ATP-dependent K+ (KATP) channel. Surprisingly, however, when islets were depolarized directly using either of two agonists, glyburide (which does not act via generation of purine nucleotides) or 40 mM K+ (which acts distal to KATP channel), PLC and insulin secretion were again obliterated by IL-1 beta. IL-1 beta also reduced the labeling of phosphoinositide substrates; however, this effect was insufficient to explain the inhibition of PLC, since the effects on substrate labeling, but not on PLC, were prevented by coprovision of guanosine or adenosine. Furthermore, when IL-1 beta treated islets were exposed to 100 microM carbachol (which activates PLC partially independent of extracellular Ca2+), the effects were still obliterated by IL-1 beta. These data (together with the finding that IL-1 beta inhibited Ca(2+)-induced insulin release) suggest that, in addition to its effects on ATP synthesis and thereby on the KATP channel, IL-1 beta has at least two undescribed, distal effects to block both PLC as well as Ca(2+)-induced exocytosis. The latter correlated best with IL-1 beta's effect to impede phosphoinositide synthesis, since it also was reversed by guanosine or adenosine. PMID- 9374681 TI - Alterations in cardiac contractility and gene expression during low-T3 syndrome: prevention with T3. AB - The low-T3 syndrome is a metabolic response resulting in a decreased serum triiodothyronine (T3) concentration that has uncertain effects on thyroid hormone responsive gene expression and function. We measured cardiac myocyte gene expression and cardiac contractility in young adult female rats using chronic calorie deprivation as a model of the low-T3 syndrome. Sarcoplasmic reticulum calcium adenosinetriphosphatase (SERCA2) and myosin heavy chain (MHC) isoform mRNA content were measured after 28 days on a 50% calorie-restricted diet (low T3) with or without T3 treatment (6 micrograms.kg body wt-1.day-1). The low-T3 animals had decreased maximal rates of contraction (-13%; P < 0.05) and relaxation (-18%; P < 0.05) compared with the control and the T3-treated groups. There was a 21% (P < 0.05) increase in left ventricular (LV) relaxation time in the low-T3 animals vs. both control and T3-treated groups. The LV content of the SERCA2 mRNA was decreased significantly (37%) in the low-T3 rats and was increased (P < 0.05) with T3 treatment vs. controls. The alpha-MHC mRNA isoform decreased in the low-T3 animals but was unchanged in the T3-treated animals. T3 supplementation normalized both cardiac function and phenotype of calorie restricted animals, suggesting a role for the low-T3 syndrome in the pathophysiological response to calorie restriction. PMID- 9374682 TI - Structure and activity of uroguanylin and guanylin from the intestine and urine of rats. AB - Uroguanylin and guanylin are related peptides that activate common guanylate cyclase signaling molecules in the intestine and kidney. Uroguanylin was isolated from urine and duodenum but was not detected in extracts from the colon of rats. Guanylin was identified in extracts from small and large intestine but was not detected in urine. Uroguanylin and guanylin have distinct biochemical and chromatographic properties that facilitated the separation, purification, and identification of these peptides. Northern assays revealed that mRNA transcripts for uroguanylin were more abundant in small intestine compared with large intestine, whereas guanylin mRNA levels were greater in large intestine relative to small intestine. Synthetic rat uroguanylin and guanylin had similar potencies in the activation of receptors in T84 intestinal cells. Production of uroguanylin and guanylin in the mucosa of duodenum is consistent with the postulate that both peptides influence the activity of an intracellular guanosine 3',5'-cyclic monophosphate signaling pathway that regulates the transepithelial secretion of chloride and bicarbonate in the intestinal epithelium. PMID- 9374683 TI - Electroretinogram in sucrose-fed diabetic rats treated with an aldose reductase inhibitor or an anticoagulant. AB - To investigate the role of increased polyol pathway activity and hemodynamic deficits in the pathogenesis of diabetic retinopathy in non-insulin-dependent diabetes mellitus (NIDDM), Otsuka Long-Evans Tokushima fatty (OLETF) rats, an animal model of human NIDDM, were given water with or without 30% sucrose and some of them were fed laboratory chow containing 0.03% cilostazol, an anticoagulant, or 0.05% [5-(3-thienyl)tetrazol-1-yl] acetic acid monohydrate (TAT), an aldose reductase inhibitor, for 8 wk. Long-Evans Tokushima Otsuka (LETO) rats were used as nondiabetic controls. The peak latencies of oscillatory potentials of the electroretinogram in sucrose-fed OLETF rats were significantly prolonged compared with those in OLETF rats without sucrose feeding and LETO rats. There was a marked increase in platelet aggregability and a significant decrease in erythrocyte 2,3-diphosphoglycerate in sucrose-fed OLETF rats. Cilostazol significantly improved these parameters without changes in retinal levels of sorbitol and fructose. TAT, however, ameliorated all of these parameters. These findings confirm that the sucrose-fed OLETF rat is a useful animal model of retinopathy in human NIDDM and suggest that cilostazol improved diabetic retinopathy by modifying vascular factors, not by altering polyol pathway activity. PMID- 9374684 TI - Interaction of equal increments in arterial and portal vein insulin on hepatic glucose production in the dog. AB - We have previously shown that a selective increase of 84 pmol/l in either arterial or portal vein insulin (independent of a change in insulin in the other vessel) can suppress tracer-determined glucose production (TDGP) and net hepatic glucose output (NHGO) by approximately 50%. In the present study we investigated the interaction between equal increments in arterial and portal vein insulin in the suppression of TDGP and NHGO. Isotopic ([3-3H]glucose) and arteriovenous difference methods were used in conscious overnight fasted dogs. A pancreatic clamp was used to control the endocrine pancreas. A 40-min basal period was followed by a 180-min test period, during which arterial and portal vein insulin levels were simulataneously and equally increased 102 pmol/l. Hepatic sinusoidal glucagon levels remained unchanged, and euglycemia was maintained by peripheral glucose infusion. TDGP was suppressed approximately 60% by the last 30 min of the experimental period. In contrast, NHGO was suppressed 100% by that time. Coincidentally, hepatic glucose uptake (net hepatic [3H]glucose balance) increased significantly (approximately 4 mumol.kg-1.min-1). The effects of simultaneous equal increases in peripheral and portal venous insulin were not additive in the suppression of TDGP. However, they were additive in decreasing NHGO as a result of an increase in the uptake of glucose by the liver. PMID- 9374686 TI - Effects of age on the irregularity of LH and FSH serum concentrations in women and men. AB - We evaluated an apparent distinction between follicle-stimulating hormone (FSH) and luteinizing hormone (LH) dynamics: visually, it appears that the pattern of serum concentrations of FSH is more irregular than that of LH in younger human females. We studied healthy humans, with LH and FSH serum samples obtained every 10 min for 24 h. Three groups were studied: 24 young females [8 early follicular (EFol), 8 late follicular (LFol), and 8 midluteal (MLut)]; 8 postmenopausal females; and 17 males 21-79 yr of age. To quantify serial irregularity, we utilized approximate entropy (ApEn), a scale- and model-independent statistic. For young females, FSH was consistently more irregular than LH per subject: among the younger subjects, ApEn(FSH) - ApEn(LH) = 0.342 +/- 0.270; ApEn(FSH) > ApEn(LH), P < 0.00001; ApEn(FSH) > ApEn(LH) for 23 of 24 subjects. For each cycle stage, pairwise ApEn(FSH) > ApEn(LH): P < 0.005 for both LFol and MLut, P < 0.01 for EFol. Notably, for the postmenopausal women, the irregularity difference vanished:ApEn(FSH) - ApEn(LH) = 0.008 +/- 0.205. Males exhibited qualitatively similar results: ApEn(FSH)- ApEn(LH) was significantly and negatively correlated with age (r = -0.75, P = 0.0006). The capability to quantify (the extent of) differences between FSH and LH release, beyond the general 1:1 correspondence between primary LH and FSH pulses, suggests a means to assess bihormonal changes as a clinical marker of altered reproductive status in a variety of settings, e.g., a perimenopausal milieu. Mechanistically, the erosion of unequal FSH-LH regularity with age is consistent with a loss of synchrony control within the integrated hypothalamo-pituitary-gonadal axis. PMID- 9374685 TI - Glucagon-like peptide 1 inhibition of gastric emptying outweighs its insulinotropic effects in healthy humans. AB - Glucagon-like peptide 1 (GLP-1) has been shown to inhibit gastric emptying of liquid meals in type 2 diabetic patients. It was the aim of the present study to compare the action of physiological and pharmacological doses of intravenous GLP 1-(7-36) amide and GLP-1-(7-37) on gastric emptying in normal volunteers. Nine healthy subjects participated (26 +/- 3 yr; body mass index 22.9 +/- 1.6 kg/m2; hemoglobin A1C 5.0 +/- 0.2%) in five experiments on separate occasions after an overnight fast. A nasogastric tube was positioned for the determination of gastric volume by use of a dye-dilution technique (phenol red). GLP-1-(7-36) amide (0.4, 0.8, or 1.2 pmol.kg-1.min-1), GLP-1-(7-37) (1.2 pmol.kg-1.min-1), or placebo was infused intravenously from -30 to 240 min. A liquid meal (50 g sucrose, 8% amino acids, 440 ml, 327 kcal) was administered at 0 min. Glucose, insulin, and C-peptide were measured over 240 min. Gastric emptying was dose dependently slowed by GLP-1-(7-36) amide (P < 0.0001). Effects of GLP-1-(7-37) at 1.2 pmol.kg-1.min-1 were virtually identical. GLP.1 dose dependently stimulated fasting insulin secretion (-30 to 0 min) and slightly reduced glucose concentrations. After the meal (0-240 min), integrated incremental glucose (P < 0.0001) and insulin responses (P = 0.01) were reduced (dose dependently) rather than enhanced. In conclusion, 1) GLP-1-(7-36) amide or -(7-37) inhibits gastric emptying also in normal subjects, 2) physiological doses (0.4 pmol.kg-1.min-1) still have a significant effect, 3) despite the known insulinotropic actions of GLP-1-(7-36) amide and -(7-37), the net effect of administering GLP-1 with a meal is no change or a reduction in meal-related insulin responses. These findings suggest a primarily inhibitory function for GLP-1 (ileal brake mechanisms). PMID- 9374687 TI - Plasmin degradation of insulin-like growth factor-binding protein-5 (IGFBP-5): regulation by IGFBP-5-(201-218). AB - Using the major bone insulin-like growth factor-binding protein (IGFBP) IGFBP-5, we took a mechanistic approach in evaluating the role of the heparin-binding domain of IGFBP-5 in regulating plasmin (Pm) proteolysis of IGFBP-5. Using synthetic IGFBP-5 peptide fragments, we determined that the heparin-binding domain, IGFBP-5-(208-218), inhibits Pm proteolysis of intact IGFBP-5. The mechanism of action of IGFBP-5-(201-218) was by inhibiting Pm binding to substrate IGFBP-5. IGFBP-5-(201-218) action was independent of site of proteolysis, fluid, or solid phase interaction. In addition, IGFBP-5-(201-218) was found to inhibit plasminogen (Pg) activation to Pm IGFBP-5-(201-218) did not directly inhibit the activity of Pm, urokinase Pg activator (PA), or tissue-type PA but acted as a competitive inhibitor of Pg activation by PA, which is in contrast to the stimulating effect of heparin on Pg activation. These data indicate that the heparin-binding domain contains the serine protease (Pg-to-Pm) binding site region of IGFBP-5, and that this region, which is presumed to represent a Pm-induced proteolytic product of IGFBP-5, is capable of regulating Pm action. PMID- 9374688 TI - Insulin-like growth factor (IGF)-binding protein-5-(201-218) region regulates hydroxyapatite and IGF-I binding. AB - Insulin-like growth factor-binding protein-5 (IGFBP-5), the major bone IGFBP, modifies the biological activity of IGFs within the osteoblastic pericellular environment. Because glycosaminoglycans modulate IGFBP-5 binding to osteoblast organic extracellular matrix (ECM), we assessed whether the heparin binding domain of IGFBP-5, IGFBP-5-(102-218), modifies the interaction of IGFBP-5 with the inorganic bone ECM hydroxyapatite (HA). Synthetic IGFBP-5-(201-218) peptide increased the binding of IGFBP-5 to HA as well as the binding of IGF-I to HA bound IGFBP-5. This action was specific for the heparin-binding domain, because IGFBP-5-(130-138), IGFBP-5-(138-152), and IGFBP-5-(1-169) were without effect. IGFBP-5-(201-218) was found to bind directly to IGFBP-5 and cause a threefold enhancement of the IGF-I binding affinity for IGFBP-5, whether IGFBP-5 was bound to HA or was in a matrix-free fluid phase. Heparin inhibited the binding of IGFBP 5 to HA and blocked the interaction of IGFBP-5 with IGFBP-5-(201-218) in the fluid phase, suggesting that the primary heparin-binding domain of IGFBP-5 specifically enhances the binding of IGFBP-5 to HA and increases IGF-I binding to IGFBP-5. PMID- 9374689 TI - Reduced insulin receptor signaling in the obese spontaneously hypertensive Koletsky rat. AB - Insulin resistance is associated with both obesity and hypertension. However, the cellular mechanisms of insulin resistance in genetic models of obese-hypertension have not been identified. The objective of the present study was to investigate the effects of genetic obesity on a background of inherited hypertension on initial components of the insulin signal transduction pathway and glucose transport in skeletal muscle and liver. Oral glucose tolerance testing in SHROB demonstrated a sustained postchallenge elevation in plasma glucose at 180 and 240 min compared with lean spontaneously hypertensive rat (SHR) littermates, which is suggestive of glucose intolerance. Fasting plasma insulin levels were elevated 18 fold in SHROB. The rate of insulin-stimulated 3-O-methylglucose transport was reduced 68% in isolated epitrochlearis muscles from the SHROB compared with SHR. Insulin-stimulated tyrosine phosphorylation of the insulin receptor beta-subunit and insulin receptor substrate-1 (IRS-1) in intact skeletal muscle of SHROB was reduced by 36 and 23%, respectively, compared with SHR, due primarily to 32 and 60% decreases in insulin receptor and IRS-1 protein expression, respectively. The amounts of p85 alpha regulatory subunit of phosphatidylinositol-3-kinase and GLUT 4 protein were reduced by 28 and 25% in SHROB muscle compared with SHR. In the liver of SHROB, the effect of insulin on tyrosine phosphorylation of IRS-1 was not changed, but insulin receptor phosphorylation was decreased by 41%, compared with SHR, due to a 30% reduction in insulin receptor levels. Our observations suggest that the leptin receptor mutation fak imposed on a hypertensive background results in extreme hyperinsulinemia, glucose intolerance, and decreased expression of postreceptor insulin signaling proteins in skeletal muscle. Despite these changes, hypertension is not exacerbated in SHROB compared with SHR, suggesting these metabolic abnormalities may not contribute to hypertension in this model of Syndrome X. PMID- 9374690 TI - The hot IVGTT two-compartment minimal model: indexes of glucose effectiveness and insulin sensitivity. AB - A two-compartment minimal model (2CMM) has been proposed [A. Caumo and C. Cobelli. Am. J. Physiol. 264 (Endocrinol. Metab. 27): E829-E841, 1993] to describe intravenous glucose tolerance test (IVGTT) labeled (hereafter hot) glucose kinetics. This model, at variance with the one-compartment minimal model (1CMM), allows the estimation of a plausible profile of glucose production. The aim of this study is to show that the 2CMM also allows the assessment of insulin sensitivity (SI2*), glucose effectiveness (SG2*), and plasma clearance rate (PCR). The 2CMM was identified on stable-isotope IVGTTs performed in normal subjects (n = 14). Results were (means +/- SE) SG2* = 0.85 +/- 0.14 ml.kg-1.min 1, PCR = 2.02 +/- 0.14 ml.kg-1.min-1, and SI2* = 13.83 +/- 2.54 x 10(-2) ml.kg 1.min-1.microU-1.ml. The 1CMM was also identified; glucose effectiveness and insulin sensitivity indexes were SG*V = 1.36 +/- 0.08 ml.kg-1.min-1 and SI*V = 12.98 +/- 2.21 x 10(-2) ml.kg-1.min-1.microU-1.ml, respectively, where V is the 1CMM glucose distribution volume. SG*V was lower than PCR and higher than SG2* and did not correlate with either [r = 0.45 (NS) and r = 0.50 (NS), respectively], whereas SI*V was not different from and was correlated with SI2* (r = 0.95; P < 0.001). SG* compares well (r = 0.78; P < 0.001) with PCR normalized by the 2CMM total glucose distribution volume. In conclusion, the 2CMM is a powerful tool to assess glucose metabolism in vivo. PMID- 9374691 TI - Regional differences in interstitial glycerol concentration in subcutaneous adipose tissue of women. AB - The aims of this study were to 1) compare two methods of determining interstitial glycerol concentration in subcutaneous adipose tissue (AT) and 2) determine whether there are regional differences in interstitial glycerol concentration in subcutaneous AT of nonobese, premenopausal women. Microdialysis probes were inserted under local anesthesia into the abdominal (2 probes) and femoral (1 probe) subcutaneous AT in each subject (n = 5) and perfused with a Ringer solution containing 2.5 mM glucose and glycerol in concentrations ranging from 0 to 900 microM. Microdialysis probe relative recoveries and interstitial glycerol concentrations were determined by the no-net-flux method (NNF) and the internal reference method (IR) with the use of [13C]glycerol. Microdialysis probe relative recoveries were 57.4 +/- 3.6% by NNF and 61.2 +/- 10.1% by IR in femoral AT [P = not significant (NS)] and were 55.2 +/- 6.0% by NNF and 66.6 +/- 4.2% by IR in abdominal AT (P = NS). The calculated interstitial glycerol concentrations determined by NNF and IR were 236.4 +/- 42.7 and 241.1 +/- 39.6 microM (P = NS) in femoral AT and 151.4 +/- 29.7 and 129.4 +/- 18.7 microM in abdominal AT (NNF vs. IR, P = NS; femoral vs. abdominal, P < 0.05). It can be concluded that the interstitial glycerol concentration in the femoral AT of nonobese, premenopausal females is approximately 240 microM and is higher than in abdominal AT (140 microM). Furthermore, the use of a stable isotope of glycerol as an internal reference is suitable for determining interstitial glycerol concentrations in subcutaneous adipose tissue in humans at rest. PMID- 9374692 TI - Epithelial cell growth and differentiation. V. Transcriptional regulation, development, and neoplasia of the intestinal epithelium. AB - Coordination of gene transcription is a critical regulatory step in orchestrating developmental, differentiation, and adaptation processes in the mammalian intestinal epithelium. An understanding of the regulatory network of nuclear proteins that direct transcriptional initiation of intestinal genes will provide insight into the mechanisms of normal development and differentiation as well as disease processes such as neoplasia. PMID- 9374693 TI - Cell adhesion and migration. II. Leukocyte-endothelial cell adhesion in the digestive system. AB - The adhesion of leukocytes to vascular endothelial cells is a highly coordinated process that is governed by a number of factors, including the expression of specific adhesion glycoproteins, physical forces generated within the microcirculation, and inflammatory mediators released by a variety of activated cells. The digestive system, with its large resident population of immune cells and its tremendous capacity to generate inflammatory mediators, has proven to be a valuable source of information on the mechanisms involved in the regulation of leukocyte-endothelial cell adhesion. This article considers some of the evolving issues that have surfaced as a consequence of the rapidly growing body of literature on this topic. Particular emphasis is devoted to unresolved issues related to the expression and shedding of endothelial cell adhesion molecules, the contribution of capillaries to the inflammatory response, and the role of mast cells, macrophages and lymphocytes in the modulation of leukocyte endothelial cell adhesion. PMID- 9374694 TI - Novel insights into histamine H2 receptor biology. AB - Histamine exerts multiple biological actions through one of three receptor subtypes (H1, H2, and H3). This review focuses on new developments regarding the structure and function of the H2 receptor. In addition to the important role this receptor plays in stimulating gastric acid secretion, recent studies have demonstrated that it is also involved in regulating gastrointestinal motility and intestinal secretion. The potential role of the H2 receptor in regulating cell growth and differentiation has also been added to the list of actions this biogenic amine may exert in both normal and transformed tissues. Molecular cloning of the gene indicates that it has the structural characteristics of a heptahelical G protein-linked receptor. Site-directed mutagenesis studies of this receptor reveal the presence of key amino acids within the third and fifth transmembrane domains that are critical for ligand recognition. Molecular approaches have also shed light on the structural components of the H2 receptor important in regulating desensitization and internalization. Although the H2 receptor was classically thought to couple to the adenylate cyclase pathway, recent work with the cloned receptor indicates that it can also activate the phosphoinositide signaling cascade through an independent G protein-dependent mechanism. The novel observation that histamine may stimulate c-fos gene expression lends further support to the possible role of this receptor in regulating cell growth and differentiation. PMID- 9374695 TI - Adrenergic modulation of human colonic motor and sensory function. AB - The effects of pharmacological modulation of adrenergic receptors on colonic motor and sensory function are unclear. We studied 40 healthy volunteers in a single-blind design; 12 received saline, and the remaining 28 received either clonidine, yohimbine, phenylephrine, or ritodrine. A barostat-manometric assembly in the left colon recorded drug effects on fasting and postprandial motor function, compliance, and sensation in response to standardized phasic balloon distensions delivered in random order. Clonidine reduced and yohimbine increased fasting, but not postprandial tone, by 63.2 +/- 22.3% and 24.8 +/- 8.8% (SE), respectively. Clonidine tended to reduce fasting phasic activity in the descending and sigmoid colon. A power exponential model provided the best fit to the compliance curve. Clonidine significantly increased colonic compliance. Clonidine reduced and yohimbine increased colonic perception of pain but not gas sensation during distension. Phenylephrine and ritodrine did not influence colonic motor or sensory function in the present studies. Thus alpha 2-receptors modulate fasting colonic tone and compliance and alter perception of pain but not gas during mechanical stimulation of the colon. PMID- 9374696 TI - Role of nitric oxide in gut ischemia-reperfusion-induced hepatic microvascular dysfunction. AB - The overall objective of this study was to assess the contribution of an altered bioavailability of nitric oxide (NO) to the leukocyte adhesion and hypoxic stress elicited in the liver by gut ischemia-reperfusion (I/R). The accumulation of leukocytes, number of nonperfused sinusoids (NPS), and NADH autofluorescence were monitored (by intravital microscopy) in mouse liver after 15 min of superior mesenteric artery occlusion and 60 min of reperfusion. Leukostasis, NPS, and NADH autofluorescence (indicating hypoxia) were all increased in the liver at 60 min after gut I/R. The NO synthase inhibitor NG-monomethyl-L-arginine (L-NMMA) exaggerated the liver leukostasis elicited by gut I/R, responses that were prevented by coadministration of L-arginine. The NO donor diethylenetriamine-NO (DETA-NO) and L-arginine were both effective in attenuating the gut I/R-induced leukostasis and increased NADH autofluorescence, whereas neither DETA nor D arginine exerted a protective action. These findings indicate that NO is an important determinant of the liver leukostasis, impaired sinusoidal perfusion, and tissue hypoxia elicited by gut I/R. PMID- 9374697 TI - Epidermal growth factor attenuates Clostridium difficile toxin A- and B-induced damage of human colonic mucosa. AB - Epidermal growth factor (EGF) exhibits a cytoprotective effect on gastrointestinal epithelia via a receptor-mediated mechanism. We investigated the effect of EGF on Clostridium difficile toxin A (TxA)- and toxin B (TxB)-induced damage of human colon. Ussing-chambered colonic mucosa was exposed serosally to EGF before and during luminal exposure to TxA and TxB. Resistance was calculated from potential difference and short-circuit current. Epithelial damage was assessed by light microscopy and alteration of F-actin by fluoresceinated phalloidin. Luminal exposure of colonic strips to TxA and TxB caused a time- and dose-dependent decrease in electrical resistance, necrosis and dehiscence of colonocytes, and disruption and condensation of enterocyte F-actin. These effects were inhibited by prior, but not simultaneous, serosal application of EGF (20 nM). Administration of the tyrosine kinase inhibitor genistein (10(-6) M) inhibited the protective effects of EGF. We conclude that EGF protects against TxA and TxB probably by stabilizing the cytoskeleton, the main target of these toxins. PMID- 9374698 TI - Enterohepatic circulation of scymnol sulfate in an elasmobranch, the little skate (Raja erinacea). AB - The sulfated bile alcohol scymnol sulfate (ScyS), 3 alpha,7 alpha,12 alpha,24 xi, 26,27-hexahydroxy-5 beta-cholestane-26(27)-sulfate, is the major bile salt in bile of an elasmobranch, the little skate. To investigate hepatic transport of bile alcohols in skate liver, [3H]ScyS and a potential precursor, 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestane (chtriol), were used as model compounds. Their transport into isolated hepatocytes was partially saturable, temperature sensitive, and Na+ independent. The uptake of ScyS was inhibited by cholyltaurine, and uptake of cholyltaurine was inhibited by ScyS in a competitive manner. In contrast, uptake of chtriol was not inhibited by cholyltaurine, suggesting separate transport systems. ScyS and chtriol showed a choleretic effect in isolated perfused livers. When ScyS was added to the perfusate of isolated perfused livers, > 25% was found in bile within 7 h. When chtriol was added to the perfusate, 10% of the dose was secreted into the bile mainly in the form of polar metabolites, whereas only nonmetabolized chtriol remained in the livers. The slow bile flow of 40-50 microliters/h and the high recovery in the liver suggest that metabolism may be the rate-limiting step in the hepatic elimination of chtriol. The major metabolites secreted into bile were identified by mass spectrometry and chromatography as scymnol and ScyS. To study the enterohepatic circulation, [3H]ScyS or [3H]chtriol was administered into the duodenum of free-swimming skates, and bile was collected through exteriorized indwelling cannulas over a 4-day period. More than 90% of the radioactivity was recovered from bile, indicating that there was a highly effective absorption in the intestinal epithelium, as well as specific transport mechanisms for hepatic uptake and biliary secretion of these compounds. This is the first direct demonstration of an enterohepatic circulation for a bile alcohol sulfate in fish liver. PMID- 9374699 TI - alpha 1-Acid glycoprotein reduces local and remote injuries after intestinal ischemia in the rat. AB - The aim of this study was to look at the role of alpha 1-acid glycoprotein as a natural anti-inflammatory agent with particular respect to its antineutrophil and anticomplement activity. A recombinantly engineered form of sialyl Lewisx (sLe(x))-bearing alpha 1-acid glycoprotein (sAGP) was administered intravenously to pentobarbital-anesthetized rats after 50 min of intestinal ischemia just before 4 h of reperfusion. A non-sLe(x)-bearing form of AGP (nsAGP) was used as control. sAGP-treated animals had a 62% reduction (P < 0.05) in remote lung injury, assessed by 125I-albumin permeability, compared with those treated with nsAGP (permeability index of 3.61 +/- 0.15 x 10(-3) and 5.18 +/- 0.67 x 10(-3), respectively). There was a reduction in pulmonary myeloperoxidase levels in sAGP treated rats compared with nsAGP-treated rats. Complement-dependent intestinal injury, assessed by 125I-albumin permeability was reduced by 28% (P < 0.05) in animals treated with sAGP (7.58 +/- 0.63) compared with those treated with nsAGP (10.4 +/- 0.54). We conclude that sAGP ameliorates both complement- and neutrophil-mediated injuries. PMID- 9374700 TI - Endothelin-1 selectively contracts portal vein through both ETA and ETB receptors in isolated rabbit liver. AB - We determined the constrictive effects of endothelin (ET)-1 on the hepatic vascular resistance distribution and the receptor subtype responsible for the effect in isolated rabbit livers perfused via the portal vein with 5% albumin Krebs solution. The sinusoidal pressure was estimated using the double vascular occlusion pressure. The basal portal venous resistance comprised 59% of the total portal-hepatic venous resistance. In response to a bolus injection of ET-1 (0.05 5 micrograms), which led to a final concentration of 0.1-10 nM in the recirculating perfusate, the portal venous resistance increased in a dose dependent manner, whereas the hepatic venous resistance did not change significantly at any concentration. This hepatic vasoconstriction was associated with liver weight loss. The selective portal venous constriction induced by ET-1 was confirmed in livers perfused retrogradely from the hepatic vein to the portal vein. The ET-1-induced hepatic vasoconstriction was significantly attenuated by the selective ETA receptor antagonist BQ-123 (1 microM). The ETB receptor antagonist BQ-788 (1 microM) also attenuated the constriction at ET-1 concentrations less than 10 nM. The combination of BQ-123 and BQ-788 tended to inhibit the hepatic vasoconstriction more effectively than BQ-123 alone. These results suggest that ET-1 selectively constricts the portal vein via both ETA and ETB receptors, with predominance of ETA receptor in isolated albumin-Krebs perfused rabbit livers. PMID- 9374701 TI - Neuronal release of endogenous dopamine from corpus of guinea pig stomach. AB - Neuronal release of endogenous dopamine was identified in mucosa-free preparations (muscle layer including intramural plexus) from guinea pig stomach corpus by measuring tissue dopamine content and dopamine release and by immunohistochemical methods using a dopamine antiserum. Dopamine content in mucosa-free preparations of guinea pig gastric corpus was one-tenth of norepinephrine content. Electrical transmural stimulation of mucosa-free preparations of gastric corpus increased the release of endogenous dopamine in a frequency-dependent (3-20 Hz) manner. The stimulated release of dopamine was prevented by either removal of external Ca2+ or treatment with tetrodotoxin. Dopamine-immunopositive nerve fibers surrounding choline acetyltransferase immunopositive ganglion cells were seen in the myenteric plexus of whole mount preparations of gastric corpus even after bilateral transection of the splanchnic nerve proximal to the junction with the vagal nerve (section of nerves between the celiac ganglion and stomach). Domperidone and sulpiride potentiated the stimulated release of acetylcholine and reversed the dopamine-induced inhibition of acetylcholine release from mucosa-free preparations. These results indicate that dopamine is physiologically released from neurons and from possible dopaminergic nerve terminals and regulates cholinergic neuronal activity in the corpus of guinea pig stomach. PMID- 9374703 TI - Gastrin inhibits secretin-induced ductal secretion by interaction with specific receptors on rat cholangiocytes. AB - We assessed the effect of gastrin on ductal secretion in normal and bile duct ligated (BDL) rats. The effect of gastrin on ductal secretion was examined in the presence of proglumide, a specific antagonist for gastrin receptor (GR). We isolated pure cholangiocytes from normal and BDL rats and assessed gastrin effects on secretin receptor (SR) gene expression and intracellular adenosine 3',5'-cyclic monophosphate (cAMP) levels. We examined the presence of GR mRNA in cholangiocytes by reverse transcription polymerase chain reaction (RT-PCR). In normal or BDL rats, gastrin produced no changes in spontaneous bile secretion. Simultaneous infusion of gastrin inhibited secretin-induced choleresis and bicarbonate output in BDL rats. In the presence of proglumide gastrin did not inhibit secretin-induced choleresis in BDL rats. Gastrin decreased in cholangiocytes from BDL rats 1) SR gene expression and 2) secretin-induced cAMP levels. With the use of RT-PCR, GR mRNA was detected in cholangiocytes. Similar to what is shown for secretin and somatostatin, we propose that the opposing effects of secretin and gastrin on cholangiocyte secretory activity regulate ductal secretion in rats. PMID- 9374702 TI - Identification and functional assay of an extracellular calcium-sensing receptor in Necturus gastric mucosa. AB - In mammals and amphibians, increases in extracellular Ca2+ can activate bicarbonate secretion and other protective functions of gastric mucosa. We hypothesized that the recently cloned extracellular Ca(2+)-sensing receptor (CaR) is functioning in the gastric mucosa. In Necturus maculosus gastric mucosa, reverse transcription-polymerase chain reaction using primers based on previously cloned CaR sequences amplified a 326-bp DNA fragment that had 84% nucleotide sequence identity with the rat kidney CaR. Immunohistochemical localization of the CaR using specific anti-CaR antiserum revealed its presence on the basal aspect of gastric epithelial cells. In microelectrode studies of Necturus antral mucosa, exposure to elevated Ca2+ (4.8 mM) and the CaR agonists NPS-467 and neomycin sulfate resulted in significant hyperpolarizations of basal membrane electrical potentials and increases in apical-to-basal membrane resistance ratios. Circuit analysis revealed that these changes reflected specific decreases in basolateral membrane resistance. Inhibition of prostaglandin synthesis using indomethacin significantly attenuated these effects. We conclude that the CaR is present and functioning in Necturus gastric antrum. PMID- 9374704 TI - Influence of altered tongue contour and position on deglutitive pharyngeal and UES function. AB - The potential influence of altered lingual position and contour during the bolus loading phase of the swallow in mediating the swallowed bolus volume-dependent regulation of upper esophageal sphincter (UES) relaxation and opening was studied in 15 healthy volunteers using simultaneous videoradiography and manometry. A maxillary dental splint modulated tongue deformity during the early oral phase of deglutition. We examined the effect of the splint and swallowed bolus density on bolus volume-dependent changes in the timing of events in the swallow sequence and on hypopharyngeal intrabolus and midpharyngeal pressures. Peak mid-pharyngeal pressure (P = 0.001) and hypopharyngeal intrabolus pressure (P = 0.04) were significantly reduced by the splint. The normal volume-dependent earlier onset of sphincter relaxation and opening was preserved with the splint in situ. The splint significantly delayed the onset of hyoid motion and UES relaxation and opening without influencing transit times or total swallow duration. Alterations in tongue contour and position reduce intrabolus pressure and pharyngeal contraction without influencing normal bolus volume-dependent regulation of timing of UES relaxation and opening. PMID- 9374705 TI - Neurokinin A increases duodenal mucosal permeability, bicarbonate secretion, and fluid output in the rat. AB - The aim of this study was to examine the integrative response to neurokinin A (NKA) on duodenal mucosal permeability, bicarbonate secretion, fluid flux, and motility in an in situ perfusion model in anesthetized rats. Intravenous infusion of NKA (100, 200, and 400 pmol.kg-1.min-1) induced duodenal motility. Furthermore, duodenal mucosal bicarbonate secretion, fluid output, and mucosal permeability increased in response to NKA. Pretreatment with the nicotinic antagonist hexamethonium did not change the response in any of the parameters investigated, whereas the NK2-receptor antagonist MEN 10,627 effectively inhibited all responses to NKA. Indomethacin induced duodenal motility and stimulated bicarbonate secretion. In indomethacin-treated rats, NKA further increased motility but decreased indomethacin-stimulated bicarbonate secretion by 70%. The NKA-induced increase in mucosal permeability was unaltered by indomethacin. It is concluded that NKA not only induces motility but also increases mucosal permeability and fluid output. Furthermore, the neuropeptide may have both stimulative and inhibitory effects on bicarbonate secretion. All responses to NKA are dependent on NK-2 receptor activation but are not mediated through nicotinic receptors. PMID- 9374707 TI - Pentoxifylline blocks hepatic stellate cell activation independently of phosphodiesterase inhibitory activity. AB - Activated, but not quiescent, hepatic stellate cells (lipocytes) have a high level of collagen type I and smooth muscle actin (SMA) gene expression. Therefore, stellate cell activation is a critical step in hepatic fibrosis. The mechanisms leading to stellate cell activation in vivo are unknown. The characteristic hepatic oxidative stress cascade induced in rats by CCl4 markedly stimulated stellate cell entry into S phase, nuclear factor (NF)-kappa B activity, and c-myb expression. These changes were prevented by pentoxifylline, which also decreased CCl4-induced hepatic injury. As expected, cAMP-mediated phosphorylation of CREB-Ser133 was induced in vivo in stellate cells by pentoxifylline but not by its metabolite 5, an N-1 carboxypropyl derivative, which lacks phosphodiesterase inhibitory activity. Stellate cell nuclear extracts from CCl4-treated, but not from control, animals formed a complex with the critical promoter E box of the alpha-SMA gene, which was disrupted by c-myb antibodies and competed with by c-myb cognate DNA. Treatment with pentoxifylline or metabolite 5 prevented the molecular abnormalities characteristic of stellate cell activation induced by CCl4. These results suggest that induction of c-myb plays an important role in the in vivo activation of stellate cells. Pentoxifylline blocks stellate cell activation in vivo independently of its inhibitory effects on phosphodiesterases by interfering with the oxidative stress cascade and the activation of NF-kappa B and c-myb. PMID- 9374708 TI - Induction of nitric oxide synthase in rat gastric smooth muscle preparations. AB - The induction in vitro of inducible nitric oxide synthase (iNOS) in intact gastric circular (CM) and longitudinal (LM) smooth muscle preparations was evaluated 1) pharmacologically, by the appearance of 1 mM L-arginine (L-Arg) induced relaxation in a precontracted tissue; 2) biochemically, according to the appearance of iNOS mRNA using a reverse transcriptase-polymerase chain reaction; and 3) immunohistochemically, using an iNOS-specific antibody. Functionally, iNOS induction affected the contractile properties of the CM but not the LM preparation. The time course of iNOS induction monitored pharmacologically paralleled exactly the appearance of iNOS mRNA. The relaxant response to L-Arg in iNOS-induced CM tissues was blocked by the iNOS inhibitor aminoguanidine and by the guanylyl cyclase inhibitor LY-83583. The addition of oxyhemoglobin to the organ bath also attenuated the relaxant response, but tetrodotoxin had no effect. The transcriptional inhibitor actinomycin D completely blocked iNOS induction as assessed by both pharmacological and biochemical criteria. In iNOS-induced preparations the iNOS immunoreactivity was not detected in the smooth muscle elements but was localized in a layer of macrophage-related cells that were in apposition to the CM smooth muscle elements. We conclude that the spontaneous induction of iNOS in rat gastric tissue can affect the pharmacomechanical reactivity of the CM elements and that this regulation of the CM contractility is due to the induction of iNOS in a set of macrophage-related cells that are closely apposed to the CM elements so that they selectively affect only the contractility of the CM preparation. PMID- 9374706 TI - Role of maxi-K+ channels in endothelin-induced vasoconstriction of mesenteric and submucosal arterioles. AB - The action of endothelin in small intestinal resistance vessels of the guinea pig was studied by examining submucosal arteriole vasoactivity in vitro and electrical properties of mesenteric arteriole smooth muscle cells. Endothelin-1 (ET-1) constricted submucosal arterioles with a half-maximal effective concentration of 170 pM. ET-3 caused detectable constriction with a minimum of 20 nM. The ET-1 response was prolonged, with a time to 90% relaxation of 41 +/- 2.8 min after washout. The ETA antagonist BQ-123 (200 nM) decreased the sensitivity to ET-1 approximately 40-fold. Arterioles preconstricted with prostaglandin F2 alpha did not relax when superfused with ET-1, ET-3, or an ETB agonist, IRL-1620, and pretreatment with the nitric oxide synthase inhibitor NG-monomethyl-L arginine was ineffective in countering ET-1-induced constriction, indicating the absence of functional ETB receptors. Resting membrane potential in isolated cells was characterized by transient hyperpolarizing spikes (THs). ET-1 (20 nM) increased TH frequency and caused the emergence of a larger amplitude population. Under voltage clamp, spontaneous transient outward currents (STOCs) were seen that reversed at the K+ equilibrium potential. ET-1 increased STOC frequency and amplitude. Iberiotoxin (IBTX; 200 nM), a maxi-K+ channel antagonist, blocked the ET-1-induced THs and reduced STOC activity. IBTX or tetraethylammonium increased the rate and extent of ET-1-induced arteriole constriction. We suggest that ET-1 induced vasoactivity of ileal resistance arterioles involves ETA receptor mediated early activation of maxi-K+ channels that serves to counter strong constriction. PMID- 9374709 TI - Regulation of biliary secretion through apical purinergic receptors in cultured rat cholangiocytes. AB - To evaluate whether ATP in bile serves as a signaling factor regulating ductular secretion, voltage-clamp studies were performed using a novel normal rat cholangiocyte (NRC) model. In the presence of amiloride (100 microM) to block Na+ channels, exposure of the apical membrane to ATP significantly increased the short-circuit current (Isc) from 18.2 +/- 5.9 to 52.8 +/- 12.7 microA (n = 18). The response to ATP is mediated by basolateral-to-apical Cl- transport because it is inhibited by 1) the Cl- channel blockers 4,4'-diisothiocyanostilbene-2,2' disulfonic acid (1 mM), diphenylanthranilic acid (1.5 mM), or 5-nitro-2-(3 phenylpropylamino)benzoic acid (50 or 100 microM) in the apical chamber, 2) the K+ channel blocker Ba2+ (5 mM), or 3) the Na(+)-K(+)-2Cl- cotransport inhibitor bumetanide (200 microM) in the basolateral chamber. Other nucleotides stimulated an increase in Isc with a rank order potency of UTP = ATP = adenosine 5'-O-(3) thiotriphosphate, consistent with P2u purinergic receptors. ADP, AMP, 2 methylthioadenosine 5'-triphosphate, and adenosine had no effect. A cDNA encoding a rat P2u receptor (rP2uR) was isolated from a liver cDNA library, and functional expression of the corresponding mRNA in Xenopus laevis oocytes resulted in the appearance of ATP-stimulated currents with a similar pharmacological profile. Northern analysis identified hybridizing mRNA transcripts in NRC as well as other cell types in rat liver. These findings indicate that exposure of polarized cholangiocytes to ATP results in luminal Cl- secretion through activation of P2u receptors in the apical membrane. Release of ATP into bile may serve as an autocrine or paracrine signal regulating cholangiocyte secretory function. PMID- 9374710 TI - pH-dependent changes of nitric oxide, peroxynitrite, and reactive oxygen species in hepatocellular damage. AB - Low arterial blood pH and sustained nitric oxide (NO) production are critical parameters in inflammatory events such as sepsis, and appropriate treatment is still under debate. Because the stability of nitrogen and oxygen intermediates is dependent on the surrounding pH, we investigated whether the relationship among NO, peroxynitrite (ONOO-), and reactive oxygen species production also depends on the pH value, particularly with respect to their effects on hepatocellular damage. Our studies demonstrate that the extracellular pH influences NO and hydroxyl radical (OH) production in hepatocytes. Acidification (pH 7.0) of the medium revealed a significant increase (P < 0.05) of OH-like radicals, enhanced hepatocellular damage, and a sharp drop in cellular glutathione (GSH) content compared with levels measured at physiological or alkaline pH conditions. Furthermore, inhibition of NO synthesis at all pH conditions resulted in decreased NO production and cellular GSH levels but a simultaneous increase of OH like radicals and hepatocellular damage with a maximum seen at pH 7.0. Our results suggest that hepatocellular damage is in part regulated by the surrounding pH and that inhibition of NO synthesis at acidic conditions (e.g., in sepsis) leads to increased reactive oxygen-mediated cell injury. PMID- 9374711 TI - Cellular pathways mediating tachykinin-evoked secretomotor responses in guinea pig ileum. AB - This study characterized tachykinin-evoked secretomotor responses in in vitro submucosal and mucosal-submucosal preparations of the guinea pig ileum using combined intracellular and Ussing chamber recording techniques. Superfusion of endogenous tachykinins substance P (SP), neurokinin A (NKA), and neurokinin B depolarized single submucosal neurons and evoked increased short-circuit current (Isc) responses in Ussing chamber preparations. The NK1-receptor agonist [Sar9,Met(O2)11]SP [50% effective concentration (EC50) = 2 nM] depolarized all submucosal neurons examined. The NK3-receptor agonist senktide (EC50 = 20 nM) depolarized approximately 50% of neurons examined, whereas the NK2-receptor agonist [Ala5,beta-Ala8]NKA-(4-10) had no effect on membrane potential. [Sar9,Met(O2)11]SP and senktide evoked similar increases in Isc that were tetrodotoxin sensitive (91 and 100%, respectively) and were selectively blocked by the NK1 antagonist CP-99,994 and the NK3 antagonist SR-142,801, respectively. Capsaicin-evoked increases in Isc were significantly inhibited (54%, P < 0.05) by CP-99,994 but not by SR-142,801. Neither antagonist inhibited slow excitatory postsynaptic potentials. These findings suggest that tachykinin-evoked secretion in guinea pig ileum is mediated by NK1 and NK3 receptors on submucosal secretomotor neurons and that capsaicin-sensitive nerves release tachykinin(s) that activate the NK1 receptors. PMID- 9374712 TI - Alpha 2-adrenergic modulation of colonic tone during hyperventilation. AB - Our aims were to assess the role of adrenergic modulation in the hyperventilation induced increase in colonic tone. Of 40 healthy volunteers, 12 received placebo (saline) and the remaining 28 received either clonidine, yohimbine, phenylephrine, or ritodrine. Time-frequency mapping of heart rate based on Wigner distribution assessed variations in parasympathetic and sympathetic activity during hyperventilation. Tone in the descending colon was recorded by a barostat balloon before, during, and after 5 min of hyperventilation. Heart rate spectral analysis suggested diminished sympathetic and vagal activity during hyperventilation and increased sympathetic and vagal activity after hyperventilation. Adrenergic agents influenced (P = 0.01) the tonic response after, but not during, hyperventilation. Yohimbine reduced the increment in colonic tone after hyperventilation compared with saline (P < 0.05) and clonidine (P = 0.002); phenylephrine and ritodrine had no effects. Different mechanisms modulate the increase in colonic tone during and after hyperventilation. Yohimbine attenuates the increase in colonic tone after hyperventilation probably by enhancing inhibitory sympathetic input to the colon. PMID- 9374713 TI - Outwardly rectifying Cl- channel in guinea pig small intestinal villus enterocytes: effect of inhibitors. AB - Previous studies in enterocytes isolated from the villus region of small intestinal epithelium have identified a macroscopic current carried by Cl-. In this work a single-channel patch-clamp study was carried out in the same cells, and a spontaneously active, outwardly rectifying Cl- channel was identified and proposed to underlie the whole cell current. The channel had conductances of 62 and 19 pS at 80 and -80 mV, respectively, in symmetrical Cl- solutions in excised patches. Similar activity was seen in cell-attached patches, but only outward currents could be discerned in this configuration. The activity of the channel, measured as open probability, was independent of intracellular calcium levels and voltage. The selectivity sequence for different anions was SCN- > I- > Br- > Cl- > F- > (gluconate, glutamate, SO4(2-)). The channel was inhibited by 5-nitro-2-(3 phenylpropylamino)benzoic acid (NPPB), verapamil, and 4-hydroxytamoxifen (but not by tamoxifen), with potencies similar to those observed for Cl- channels previously described in other cells. Inhibition by trinitrophenyladenosine 5' triphosphate was also observed but only at depolarized potentials. At 50 mV the half-maximal inhibitory concentration was 18 nM. It is proposed that this channel plays a role in transepithelial Cl- transport and certain regulatory Cl- fluxes. PMID- 9374714 TI - Differential activation of the Stat signaling pathway in the liver after burn injury. AB - The liver plays a crucial role in the acute phase response after injury; mechanisms responsible for transducing inflammatory signals to the nucleus to initiate this response are not known. The purpose of this study was to examine the induction of the novel Stat (signal transducer and activator of transcription) pathway in the liver after burn injury. Rats were subjected to either a 60% burn or sham treatment; livers were removed over a time course and extracted for nuclear protein. We found that Stat3, but not Stat5, binding was predominantly increased in the liver after burn injury as assessed by gel mobility and "supershift" analyses. Moreover, Stat3 nuclear protein levels were increased 6- to 14-fold in the livers of burned rats compared with those of sham rats. Stat3 phosphorylation was rapidly induced after burn injury; the subsequent increase of Stat3 binding was completely blocked by preincubation with the antiphosphotyrosine antibody (4G10). We conclude that a differential and early induction of Stat3 binding activity occurs in the liver after burn injury; this induction is mediated by an increase in phosphorylation. These findings suggest an important role for Stat3 in transducting inflammatory signals to the nucleus of liver cells after a systemic burn injury. PMID- 9374715 TI - Nitric oxide production during Vibrio cholerae infection. AB - Vibrio cholerae induces massive intestinal fluid secretion that continues for the life of the stimulated epithelial cells. Enhanced regional blood flow and peristalsis are required to adapt to this obligatory intestinal secretory challenge. Nitric oxide (NO) is a multifunctional molecule that modulates blood flow and peristalsis and possesses both cytotoxic and antibacterial activity. We demonstrate that, compared with those in asymptomatic control subjects, levels of stable NO metabolites (NO2-/NO3-) are significantly increased in sera from acutely ill Peruvian patients with natural cholera infection as well as from symptomatic volunteers from the United States infected experimentally with V. cholerae. In a rabbit ileal loop model in vivo, cholera toxin (CT) elicited fluid secretion and dose-dependent increases in levels of NO2-/NO3- in the fluid (P < 0.01). In contrast, lipopolysaccharide (LPS) elicited no such effects when applied to the intact mucosa. NO synthase (NOS) catalytic activity also increased in toxin-exposed tissues (P < 0.05), predominantly in epithelial cells. The CT induced NOS activity was Ca2+ dependent and was not suppressed by dexamethasone. In conclusion, symptomatic V. cholerae infection induces NO production in humans. In the related animal model, CT, but not LPS, stimulated significant production of NO in association with increases in local Ca(2+)-dependent NOS activity in the tissues. PMID- 9374716 TI - Surfactant convertase action is not essential for surfactant film formation. AB - A serine-active enzyme, "surfactant convertase", is required for the conversion of surfactant from the tubular myelin (TM) form to the small vesicular (SV) form. This transformation involves at least two steps, the conversion of TM to a surface-active film at the air-fluid interface and the reorientation of the film into the surface-inactive SV form; we asked if convertase was required for the first of these steps. Rat and mouse TMs were pretreated with diisopropyl fluorophosphate (DFP) to inactivate endogenous convertase activity or with vehicle and then were analyzed for their ability to lower surface tension in vitro as an index of the conversion of TM to a surface film. DFP pretreatment did not alter the ability of TM preparations to lower surface tension, as assessed by pulsating bubble, and it did not affect the behavior of TM in a surface balance. In an experiment designed to test the ability of TM to feed a surface film to exhaustion, TMs that had been pretreated with DFP or vehicle performed similarly. These experiments show that convertase activity is not required for the conversion of TM to a monolayer and suggest, instead, that convertase acts at a post surface film stage. PMID- 9374717 TI - Glycosylation differences between a cystic fibrosis and rescued airway cell line are not CFTR dependent. AB - Altered glycosylation of mucus and membrane glycoconjugates could explain reported differences in binding of bacterial pathogens to cystic fibrosis (CF) versus normal tissue. However, because bacteria can alter cell surface glycoconjugates, it is not possible to assess the role of cystic fibrosis transmembrane conductance regulators (CFTR) in glycosylation in these studies. To address this issue, we have developed quantitative lectin binding assays to compare cell surface glycosylation in well-matched immortalized CF cells and rescued cell lines. The CF airway bronchial epithelial cell line IB3-1 consistently bound more peanut agglutinin (PNA) than its clonal derivative S9, which stably expresses functional wild-type CFTR. Pretreatment with neuraminidase increased PNA binding and abolished the difference between the two cell lines. However, infection of the IB3-1 cells with a replication-deficient recombinant adenovirus encoding CFTR restored CFTR function but did not alter PNA binding to cells. In contrast, treatment with the weak base ammonium chloride increased PNA binding to both cell lines as expected. Our data show that even clonally related CF and rescued cells can exhibit significant differences in carbohydrate processing. Although the differences that we found are consistent with the proposed role for CFTR in modulating intraorganellar pH, our data strongly suggest that they are CFTR independent. These studies add a cautionary note to the interpretation of differences in glycosylation between CF and normal primary tissues and immortalized cells. PMID- 9374718 TI - Dexamethasone inhibits lung epithelial cell apoptosis induced by IFN-gamma and Fas. AB - Lung epithelium plays a central role in modulation of the inflammatory response and in lung repair. Airway epithelial cells are targets in asthma, viral infection, acute lung injury, and fibrotic lung disease. Activated T lymphocytes release cytokines such as interferon-gamma (IFN-gamma) that can cooperate with apoptotic signaling pathways such as the Fas-APO-1 pathway to induce apoptosis of damaged epithelial cells. We report that IFN-gamma alone and in combination with activation of the Fas pathway induced apoptosis in A549 lung epithelial cells. Interestingly, the corticosteroid dexamethasone was the most potent inhibitor of IFN-gamma- and IFN-gamma plus anti-Fas-induced apoptosis. IFN-gamma induced expression of an effector of apoptosis, the cysteine protease interleukin-1 beta converting enzyme, in A549 cells. Dexamethasone, in contrast, induced expression of an inhibitor of apoptosis, human inhibitor of apoptosis (hIAP-1), also known as cIAP2. We suggest that the inhibition of epithelial cell apoptosis by corticosteroids may be one mechanism by which they suppress the inflammatory response. PMID- 9374719 TI - Phosphorylation of the 27-kDa heat shock protein via p38 MAP kinase and MAPKAP kinase in smooth muscle. AB - The 27-kDa heat shock protein (HSP27) is expressed in a variety of tissues in the absence of stress and is thought to regulate actin filament dynamics, possibly by a phosphorylation/dephosphorylation mechanism. HSP27 has also been suggested to be involved in contraction of intestinal smooth muscle. We have investigated phosphorylation of HSP27 in airway smooth muscle in response to the muscarinic agonist carbachol. Carbachol increased 32P incorporation into canine tracheal HSP27 and induced a shift in the distribution of charge isoforms on two dimensional gels to more acidic, phosphorylated forms. The canine HSP27 amino acid sequence includes three serine residues corresponding to sites in human HSP27 known to be phosphorylated by mitogen-activated protein kinase-activated protein (MAPKAP) kinase-2. To determine whether muscarinic receptors are coupled to a "stress response" pathway in smooth muscle culminating in phosphorylation of HSP27, we assayed MAPKAP kinase-2 activity and tyrosine phosphorylation of p38 mitogen-activated protein (MAP) kinase, the enzyme thought to activate MAPKAP kinase-2. Recombinant canine HSP27 expressed in Escherichia coli was a substrate for MAPKAP kinase-2 in vitro as well as a substrate for endogenous smooth muscle HSP27 kinase, which was activated by carbachol. Carbachol also increased tyrosine phosphorylation of p38 MAP kinase. SB-203580, an inhibitor of p38 MAP kinases, reduced activation of endogenous HSP27 kinase activity and blocked the shift in HSP27 charge isoforms to acidic forms. We suggest that HSP27 in airway smooth muscle, in addition to being a stress response protein, is phosphorylated by a receptor-initiated signaling cascade involving muscarinic receptors, tyrosine phosphorylation of p38 MAP kinase, and activation of MAPKAP kinase-2. PMID- 9374720 TI - Cyclin D1 antisense RNA destabilizes pRb and retards lung cancer cell growth. AB - To investigate the role of cyclin D1 in the regulation of lung cancer cell growth, we created five stably transfected cell lines carrying a cyclin D1 antisense construct. The transfected cells exhibited a marked decrease in the rate of cell growth, in contrast to the original lines (A549 and NCI-H441). The expression of several cell cycle-regulating proteins, including cyclin A, the cyclin-dependent kinases (cdk) 2 and cdk4, in addition to cyclin D1 itself, was markedly decreased. The expression of one cdk inhibitor, p21WAF1/CIP1, increased in the A549-derived cell lines. A specific target of cyclin D1 activity, the growth-suppressing product of the retinoblastoma gene, pRb, exhibited decreased expression and a decreased level of phosphorylation in the transfected cells. Decreased expression of pRb due to a significant increase in its turnover rate suggested that the stability of the protein may depend on phosphorylation by cyclin D1-dependent cdk activity. In addition to the impact on pRb stability, decreased expression of cyclin D1 induced susceptibility to cell death after withdrawal of exogenous growth factors in the antisense transfected cell lines, a response that was not observed in the original cancer cell lines. We conclude that abrogation of cyclin D1 overexpression in lung cancer cells disrupts several key pathways that are required for uncontrolled cell growth and induces those that lead to cell death after growth factor deprivation. Therefore, we speculate that use of antisense cyclin D1 expression in appropriate gene vectors could be a useful method for retarding lung cancer cell growth in accessible tumors such as those of the lung epithelium. PMID- 9374721 TI - KATP channels contribute to beta- and adenosine receptor-mediated pulmonary vasorelaxation. AB - ATP-sensitive K+ (KATP) channels have been implicated in the regulation of vasomotor tone in aortic, mesenteric, and pulmonary vascular smooth muscle. Several investigators have described an association between KATP channels and isoproterenol (Iso)-stimulated relaxation responses. To study the relationship between receptor-dependent pulmonary vasorelaxation and KATP channels, we examined the response to agonists that generate adenosine 3',5'-cyclic monophosphate at two distinct levels of the signal transduction pathway after inhibition or activation of KATP channels in isolated rat pulmonary artery rings. Cumulative concentration responses to beta-adrenergic receptor stimulation (Iso), purinergic receptor stimulation [adenosine (Ado)], and direct stimulation of adenylate cyclase [forskolin (FSK)] were studied with and without concurrent inhibition of KATP channels (glibenclamide or tolbutamide). In addition, the effect of direct KATP channel activation (cromakalim) on the response to beta adrenergic and purinergic receptor stimulation was determined. Last, we investigated the influence of KATP channel inhibition on endothelium-dependent and -independent mechanisms of pulmonary vasorelaxation linked to guanosine 3',5' cyclic monophosphate production. KATP channel inhibition impaired the response to Iso and Ado. Activation of KATP channels caused a leftward shift in the dose responses of Iso and Ado, with a significant decrease in the 50% effective concentration for each agent. KATP channel inhibition did not impair the pulmonary arterial vasorelaxation response to FSK, acetylcholine, or sodium nitroprusside. KATP channels appear to contribute to beta-adrenergic and purinergic receptor-stimulated vasorelaxation in rat pulmonary arteries. PMID- 9374722 TI - Modulating phosphatidic acid metabolism decreases oxidative injury in rat lungs. AB - We determined that lisofylline, a potent inhibitor of oleate- and linoleate containing phosphatidic acid formation (half-maximal inhibitory concentration = 40 nM), prevented oxidant-mediated capillary leak in isolated rat lungs given interleukin-8 (IL-8) intratracheally and perfused with human neutrophils. Lung leak was prevented by lung, but not neutrophil, lisofylline pretreatment. Furthermore, although lisofylline inhibited IL-8-stimulated neutrophil production of phosphatidic acid in vitro, it did not prevent IL-8-stimulated neutrophil adherence, chemotaxis, or intracellular calcium mobilization or N-formyl-Met-Leu Phe (fMLP)-stimulated oxidant production in vitro. Lisofylline also prevented acute capillary leak in isolated rat lungs perfused only with the oxidant generator purine-xanthine oxidase but did not scavenge O2-(+) or H2O2 in vitro. Finally, lisofylline-mediated protection against lung leak in both models was associated with alterations in lung membrane free fatty acid acyl composition (as reflected by the decreased ratio [linoleate + oleate]/[palmitate]). We conclude that lisofylline prevented both neutrophil-dependent and neutrophil-independent oxidant-induced capillary leak in isolated rat lungs and that protection appears to be mediated by blocking intrinsic lung linoleoyl phosphatidic acid metabolism. We speculate that lisofylline, in addition to our previously reported effects on cytokine signaling by intrapulmonary mononuclear cells, alters intrinsic pulmonary capillary membrane composition and renders this barrier less vulnerable to oxidative damage. PMID- 9374723 TI - cAMP and purinergic P2y receptors upregulate and enhance inducible NO synthase mRNA and protein in vivo. AB - Adenosine 3',5'-cyclic monophosphate (cAMP) and purinergic P2y receptor agonists upregulate inducible nitric oxide (NO) synthase (iNOS) but inhibit Escherichia coli endotoxin lipopolysaccharide (LPS)- and cytokine-mediated upregulation of iNOS in cultured cells. We examined the effects of cAMP and P2y receptor agonists on the iNOS system in vivo. Intratracheal administration of dibutyryl-cAMP (DBcAMP, 0.1 and 1 mg/kg), a P2y receptor agonist [2-methylthioadenosine 5' triphosphate (MeS-ATP), 5 mg/kg], or LPS (0.6 mg/kg) to rats 2 h before bronchoalveolar lavage (BAL) increased iNOS mRNA (competitor-equalized reverse transcription-polymerase chain reaction) and iNOS protein (Western blot) in rat alveolar macrophages compared with the effects of sterile phosphate-buffered saline (0.5 ml it). At equal levels of upregulation of iNOS mRNA, 1) LPS, but not DBcAMP or MeS-ATP, upregulated nuclear transcription factor-kappa B (NF-kappa B) and 2) iNOS protein and formation of NO were greater in alveolar macrophages from LPS- and MeS-ATP-treated rats than from DBcAMP-treated rats. Administration of DBcAMP or MeS-AMP 15 min before LPS did not inhibit LPS-induced alveolar macrophage-derived iNOS mRNA, iNOS protein, and NO. Diethyldithiocarbamate (DETC, 5 mg/kg it) inhibited LPS-induced iNOS mRNA but did not affect upregulation of iNOS mRNA produced by the other agonists. We conclude that an LPS-dependent and independent pathway of iNOS mRNA induction exists in vivo. The former is activated by IPS and most cytokines, is associated with upregulation of NF-kappa B and inhibited by DETC, and elicits an inflammatory response. The latter, activated by DBcAMP and MeS-ATP, is not associated with upregulation of NF-kappa B, inhibition by DETC, or activation of inflammation. The two systems are additive in vivo rather than antagonistic. Speculatively, if the LPS-independent iNOS pathway exists in humans, the iNOS in tissues from patients taking drugs affecting cAMP or P2y receptors may be iatrogenic rather than pathogenetic in origin. PMID- 9374724 TI - Regulation of heme oxygenase-1 gene expression in vascular smooth muscle cells by nitric oxide. AB - Heme oxygenase (HO)-mediated heme degradation is the primary mechanism for production of cellular carbon monoxide (CO). Analogous to nitric oxide (NO), CO mediates physiological and cellular functions such as vasodilation, stimulation of guanylate cyclase, and neuronal transmission. In view of accumulating data demonstrating a correlation between the activity of these two gaseous molecules and that the predominant source of CO is via HO catalysis, we hypothesized that NO regulates HO expression. We demonstrate that the NO donor spermine NONOate (SNN) increases steady-state levels of HO-1 mRNA in aortic vascular smooth muscle cells (aSMC) in both a time- and dose-dependent manner. The accumulation of HO-1 mRNA that correlated with increased HO-1 protein synthesis resulted from both an increased rate of gene transcription and a decreased rate of mRNA turnover. Inhibition of the NO-induced HO-1 mRNA expression by cycloheximide suggests that new protein synthesis is required for increased HO-1 gene expression. Induction of HO-1 expression by SNN occurs in a guanosine 3',5'-cyclic monophosphate (cGMP) independent manner because exposure of cells to 8-bromoguanosine 3',5'-cyclic monophosphate, a cGMP analog, did not increase HO-1 mRNA levels, and pretreatment of cells with 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a selective guanylate cyclase inhibitor, did not prevent SNN-induced HO-1 mRNA accumulation. The antioxidant N-acetyl-L-cysteine markedly inhibited SNN-induced HO-1 mRNA expression, whereas peroxynitrite did not induce HO-1 expression in aSMC. Interestingly, CO did not attenuate NO-induced HO-1 expression through an autocrine negative feedback mechanism as had been observed for hypoxia-induced HO 1 expression. These data provide evidence for an important regulatory network between NO and CO via HO-1. PMID- 9374725 TI - Modulatory effects of PKC activity on increased 92-kDa gelatinase secretion by neonatal alveolar macrophages. AB - We previously demonstrated that alveolar macrophages (AMs) from neonatal rats can secrete more 92-kDa gelatinase than AMs from adult rats. In this study, we investigated the role of the protein kinase C (PKC) pathway in the transductional regulation of 92-kDa gelatinase secretion by rat AMs, and we also evaluated maturational changes in this role with increasing postnatal age. After AM stimulation by phorbol 12-myristate 13-acetate (PMA), we observed a dose dependent increase in gelatinase secretion that was significantly more marked in AMs from 6-day-old rats than in AMs from adult rats and that was inhibited by the PKC inhibitor calphostin C. Adenosine 3',5'-cyclic monophosphate mimetics or concanavalin A failed to induce an increase in gelatinase secretion by AMs. Time dependent variations in PKC activity after PMA stimulation differed significantly between 6-day-old rats and adult rats; PKC activity decreased in adult AMs (50%) but remained stable in 6-day-old AMs. We therefore investigated age-related differences in the intracellular proteolytic degradation of PKC, which is thought to be mediated by calpains. Leupeptin, used as a calpain inhibitor, inhibited the decrease in PKC activity after exposure of adult AMs to PMA and induced a greater than threefold increase in PMA-induced gelatinase secretion. Calpain activity was significantly lower in AM extracts from 6-day-old than from adult rats. The physiological implication of these developmental changes in 92-kDa gelatinase regulation was demonstrated by investigation of AMs from 1-day-old rats that showed a high level of spontaneous PKC-dependent gelatinase secretion coexisting with very low calpain activity. We conclude that sustained PKC activity is a key factor in the increased gelatinase secretion by AMs seen during the postnatal period and is due, at least in part, to reduced PKC degradation. PMID- 9374727 TI - Extracellular superoxide dismutase is upregulated with inducible nitric oxide synthase after NF-kappa B activation. AB - Inflammatory cytokines have been shown to upregulate secretion of the antioxidant enzyme extracellular superoxide dismutase (EC-SOD) in dermal fibroblasts and, in other cells, to stimulate production of nitric oxide (.NO). Because superoxide rapidly scavenges .NO, forming the injurious peroxynitrite anion (OONO-), we hypothesize that stimulated cells upregulate EC-SOD expression concurrently with .NO release. To test for coregulation of EC-SOD and .NO within the same cell, the timing of inducible nitric oxide synthase (iNOS) and EC-SOD transcription was measured after exposure of a rate type II pneumocyte analog, the L2 cell line, to a combination of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha). Upregulation of iNOS and EC-SOD transcription occurred after 6 h of exposure, and transcription of both genes was linked by activation of the transcription factor nuclear factor-kappa B. Both EC-SOD and iNOS were elevated in rat lung homogenates 24 h after intratracheal instillation with IFN-gamma and TNF-alpha. The observation that EC-SOD and iNOS are temporally coregulated after cytokine exposure suggests the possibility of a critical mechanism by which cells might protect .NO and avoid the formation of OONO- during inflammation. PMID- 9374726 TI - Mechanism of capsaicin-induced relaxation in equine tracheal smooth muscle. AB - The effects of capsaicin and neuropeptides were examined in equine tracheal smooth muscle (TSM). Neither capsaicin nor substance P (SP) contracted TSM. Capsaicin (100 microM) elicited relaxation in TSM contracted with methacholine. This relaxation was not mimicked by SP or calcitonin gene-related peptide (CGRP). Relaxation was not attenuated by removal of the epithelium or by pretreatment of tissue with meclofenamate or the nitric oxide (NO) synthase inhibitor NG-nitro-L arginine. Previous exposure of TSM to capsaicin did not eliminate the relaxation responses to subsequent capsaicin. Although vasoactive intestinal peptide (VIP) elicited marked relaxation that was attenuated by alpha-chymotrypsin, alpha chymotrypsin did not affect the capsaicin-induced relaxation. Capsaicin-induced relaxation was abolished by charybdotoxin, a blocker of large-conductance Ca(2+) activated K+ channels. These results indicate that capsaicin-induced equine TSM relaxation is not mediated either by neuropeptides such as SP or CGRP released from capsaicin-sensitive sensory nerves or by prostanoids, NO, or VIP. Relaxation is due to the effect of capsaicin on large-conductance Ca(2+)-activated K+ channels. The peptidergic nerves play no important role in the regulation of TSM tone in horse airways. PMID- 9374728 TI - Stimulation of protein kinase C activity by tumor necrosis factor-alpha in bovine bronchial epithelial cells. AB - Bronchial epithelial cell migration, attachment, and proliferation are important processes in response to airway injury. We have shown that tumor necrosis factor (TNF)-alpha stimulates the migration of bovine bronchial epithelial cells (BBEC) in vitro. We hypothesized that protein kinase C (PKC) may be one of the intracellular signaling mediators of TNF-alpha in BBEC. In this study, we have identified multiple PKC isoforms in BBEC and measured total cellular PKC activity. Polyclonal antibodies to the PKC-alpha, -beta 2, -delta, and -epsilon isoforms recognized protein bands around 80-90 kDa. BBEC primary cultures treated with either 500 U/ml TNF-alpha for 2-4 h or 100 ng/ml 12-O-tetradecanoylphorbol 13-acetate for 15 min resulted in three-to fivefold increases in PKC activity in the particulate fractions of crude cell lysates. This activity was inhibited by 1 microM calphostin C or 10 microM H-7. Similarly, TNF-alpha-stimulated BBEC migration was reduced at least twofold in the presence of H-7 or calphostin C. These studies suggest that the activation of PKC is necessary for TNF-alpha stimulated BBEC migration. PMID- 9374729 TI - Cyclic stretch of airway epithelium inhibits prostanoid synthesis. AB - Airway epithelial cells (AEC) metabolize arachidonic acid (AA) to biologically active eicosanoids, which contribute to regulation of airway smooth muscle tone and inflammatory responses. Although in vivo the airways undergo cyclical stretching during ventilation, the effect of cyclic stretch on airway epithelial AA metabolism is unknown. In this study, cat and human AEC were grown on flexible membranes and were subjected to cyclic stretch using the Flexercell strain unit. Cyclic stretch downregulated synthesis of prostaglandin (PG) E2, PGI2, and thromboxane A2 by both cell types in a frequency-dependent manner. The percent inhibition of prostanoid synthesis in both cell types ranged from 53 +/- 7 to 75 +/- 8% (SE; n = 4 and 5, respectively). Treatment of cat AEC with exogenous AA (10 micrograms/ml) had no effect on the stretch-induced inhibition of PGE2 synthesis, whereas treatment with exogenous PGH2 (10 micrograms/ml) overcame the stretch-induced decrease in PGE2 production. These results indicate that stretch inhibits prostanoid synthesis by inactivating cyclooxygenase. When cells were pretreated with the antioxidants catalase (100 micrograms/ml, 150 U/ml) and N acetylcysteine (1 mM), there was a partial recovery of eicosanoid production, suggesting that cyclic stretch-induced inactivation of cyclooxygenase is oxidant mediated. These results may have important implications for inflammatory diseases in which airway mechanics are altered. PMID- 9374730 TI - Mechanisms underlying TNF-alpha effects on agonist-mediated calcium homeostasis in human airway smooth muscle cells. AB - We have previously shown that tumor necrosis factor (TNF)-alpha, a cytokine involved in asthma, enhances Ca2+ responsiveness to bronchoconstrictor agents in cultured human airway smooth muscle (ASM) cells. In the present study, we investigated the potential mechanism(s) by which TNF-alpha modulates ASM cell responsiveness to such agents. In human ASM cells loaded with fura 2, TNF-alpha and interleukin (IL)-1 beta significantly enhanced thrombin- and bradykinin evoked elevations of intracellular Ca2+. In TNF-alpha-treated cells. Ca2+ responses to thrombin and bradykinin were 350 +/- 14 and 573 +/- 93 nM vs. 130 +/ 17 and 247 +/- 48 nM in nontreated cells, respectively (P < 0.0001). In IL-1 beta-treated cells, the Ca2+ response to bradykinin was 350 +/- 21 vs. 127 +/- 12 nM in nontreated cells (P < 0.0001). The time course for TNF-alpha potentiation of agonist-induced Ca2+ responses requires a minimum of 6 h and was maximum after 12 h of incubation. In addition, cycloheximide, a protein synthesis inhibitor, completely blocked the potentiating effect of TNF-alpha on Ca2+ signals. We also found that TNF-alpha significantly enhanced increases in phosphoinositide (PI) accumulation induced by bradykinin. The percentage of change in PI accumulation over control was 115 +/- 8 to 210 +/- 15% in control cells vs. 128 +/- 10 to 437 +/- 92% in TNF-alpha-treated cells for 3 x 10(-9) to 3 x 10(-6) M bradykinin. The PI turnover to 10 mM NaF, a direct activator of G proteins, was also found to be enhanced by TNF-alpha. The percentage of change in PI accumulation over control increased from 280 +/- 35% in control cells to 437 +/- 92% in TNF-alpha-treated cells. Taken together, these results show that TNF-alpha can potently regulate G protein-mediated signal transduction in ASM cells by activating pathways dependent on protein synthesis. Our study demonstrates one potential mechanism underlying the enhanced Ca2+ response to bronchoconstrictor agents induced by cytokines in human ASM cells. PMID- 9374732 TI - Heterogeneity of the composition and thickness of tracheal mucus in rats. AB - Inability to preserve airway mucus in situ has limited our understanding of its structure and function. This light- and transmission electron-microscopic study of rat tracheal mucus used a nonaqueous fixative that retains mucus (epiphase) over a lucent layer (hypophase). The fixative is a 1% solution of osmium tetroxide dissolved in a perfluorocarbon. The mean thickness of rat tracheal epiphase was 5 microns, with significant variation (0.1-50 microns) around the tracheal circumference. Tracheal mucus was thickest at the trachealis muscle region and contained cells, cellular debris, and a variable amount of surfactant and lipid, estimated at 4-16% of the total epiphase in five rats, with a mean composition of 9%. Lipid was observed on the surface of the epiphase, embedded within mucus, and at the epiphase-hypophase interface. Refined study of developmental, physiological, and pathological alterations to the airway coat may benefit from this approach. PMID- 9374731 TI - Role of extracellular signal-regulated protein kinases in apoptosis by asbestos and H2O2. AB - Stimulation of cell signaling cascades by oxidants may be important in the pathogenesis of pulmonary and pleural diseases. Here, we demonstrate in rat pleural mesothelial cells that apoptotic concentrations of crocidolite asbestos and H2O2 induce phosphorylation and activation of extracellular signal-regulated protein kinases (ERK). Activation of c-jun-NH2-terminal protein kinases (JNK)/stress-activated protein kinases was also observed in response to H2O2. In contrast, asbestos caused more protracted activation of ERK without JNK activation. Both H2O2- and asbestos-induced activation of ERK was abolished by catalase. Moreover, chelation of surface iron from crocidolite fibers or addition of N-acetyl-L-cysteine prevented ERK activation and apoptosis by crocidolite, indicating an oxidative mechanism of cell signaling. The MEK1 inhibitor PD-98059 abrogated asbestos-induced apoptosis, confirming a causal relationship between ERK activation and apoptosis. These results suggest that distinct cell-signaling cascades may be important in phenotypic responses elicited by oxidant stresses. PMID- 9374733 TI - Ca(2+)-dependent p47phox translocation in hydroperoxide modulation of the alveolar macrophage respiratory burst. AB - Oxidative stress produces dual effects on the respiratory burst of rat alveolar macrophages. Preincubation with hydroperoxide concentrations [H2O2 or tert-butyl hydroperoxide (t-BOOH); < 50 microM] enhances stimulation of the respiratory burst, whereas higher concentrations inhibit stimulation. Both the enhancement and inhibition are markedly attenuated by buffering t-BOOH-induced changes in intracellular Ca2+ concentration ([Ca2+]i). Phosphorylation of the NADPH oxidase component p47phox and its translocation from cytoplasm to plasma membrane are essential in respiratory burst activation. Phorbol 12-myristate 13-acetate (PMA) stimulated p47phox phosphorylation was negligibly affected by 25 or 100 microM t BOOH. Nonetheless, 25 microM t-BOOH increased PMA-stimulated p47phox translocation, whereas 100 microM t-BOOH decreased PMA-stimulated translocation. In unstimulated cells, however, neither phosphorylation nor translocation of p47phox was affected by t-BOOH. Buffering of the t-BOOH-mediated changes of [Ca2+]i abolished the effects of t-BOOH on PMA-stimulated translocation in parallel to effects upon the respiratory burst. The results suggest that the dual effects of hydroperoxides are mediated, in part, by Ca(2+)-dependent processes affecting the assembly of the respiratory burst oxidase at steps that are separate from p47phox phosphorylation. PMID- 9374734 TI - Glucocorticoid regulation of surfactant components in immature lambs. AB - To assess effects of dose and duration of glucocorticoid exposure on maturation of the fetal lung, we administered single or multiple doses of betamethasone (0.5 mg/kg im) to pregnant sheep for 2 or 21 days before preterm delivery at 125 days of gestation. Lung function (compliance, lung volume at 40 cmH2O pressure, and ventilatory efficiency index) was increased after two to four weekly doses of glucocorticoid (2.5- to 4-fold increase) and after 48 h of exposure (1.4- to 2.3 fold). Total protein of lavage fluid decreased similarly with three doses, four doses, and 48 h of treatment. In lambs with long-term exposure to betamethasone, there was a similar, dose-dependent increase in concentrations of saturated phosphatidylcholine and surfactant proteins A (SP-A) and B (SP-B) (maximal 2- to 3-fold in tissue and 10- to 15-fold in lavage fluid). Levels of SP-A and SP-B were closely correlated in lavage fluid. In animals treated for 48 h, only tissue SP-B was increased (2.7-fold). We conclude that 48 h of glucocorticoid treatment improves lung function in the premature lamb without a detectable increase in lavage surfactant components and that longer exposure to antenatal glucocorticoid increases surfactant lipid and proteins in a coordinated fashion. The enhanced response with repetitive dosing indicates that the process of glucocorticoid induced lung maturation is either reversible and/or gestational age dependent. PMID- 9374735 TI - Hemorrhagic shock induces G-CSF expression in bronchial epithelium. AB - Hemorrhagic shock (HS) initiates a series of inflammatory processes that includes the activation of polymorphonuclear granulocytic neutrophils (PMN). We tested the hypothesis that HS induces granulocyte colony-stimulating factor (G-CSF), a cytokine that augments PMN effector functions, in the lungs of rats. Sprague Dawley rats were subjected to compensated or decompensated HS followed by resuscitation and death at 4 or 8 h. Animals subjected to HS demonstrated acute lung injury with PMN infiltration, edema, and hypoxia. Using semiquantitative reverse transcriptase-polymerase chain reaction, we detected a 1.9- to 7.1-fold increase in G-CSF mRNA levels in the lung of animals subjected to HS compared with sham controls. Levels of G-CSF mRNA increased with increased duration of the ischemic phase of resuscitated shock. In situ hybridization revealed that bronchoepithelial cells were the major cellular site of G-CSF mRNA. Thus production of G-CSF mRNA by bronchoepithelial cells is dramatically increased in a rat model of HS that also demonstrated lung injury. Increased local G-CSF levels may contribute to PMN recruitment and activation and resultant lung injury in HS. PMID- 9374736 TI - In vivo activation of CFTR-dependent chloride transport in murine airway epithelium by CNP. AB - Inhibitors of guanosine 3',5'-cyclic monophosphate (cGMP)-inhibited phosphodiesterases stimulate Cl- transport across the nasal epithelia of cystic fibrosis mice carrying the delta F508 mutation [cystic fibrosis transmembrane conductance regulator (CFTR) (delta F/delta F)], suggesting a role for cGMP in regulation of epithelial ion transport. Here we show that activation of membrane bound guanylate cyclases by C-type natriuretic peptide (CNP) stimulates hyperpolarization of nasal epithelium in both wild-type and delta F508 CFTR mice in vivo but not in nasal epithelium of mice lacking CFTR [CFTR(-/-)]. With the use of a nasal transepithelial potential difference (TEPD) assay, CNP was found to hyperpolarize lumen negative TEPD by 6.1 +/- 0.6 mV in mice carrying wild-type CFTR. This value is consistent with that obtained with 8-bromoguanosine 3',5' cyclic monophosphate (6.2 +/- 0.9 mV). A combination of the adenylate cyclase agonist forskolin and CNP demonstrated a synergistic ability to induce Cl- secretion across the nasal epithelium of CFTR(delta F/delta F) mice. No effect on TEPD was seen with this combination when used on CFTR(-/-) mice, implying that the CNP-induced change in TEPD in CFTR(delta F/delta F) mice is CFTR-dependent. PMID- 9374737 TI - Rat alveolar macrophages express preprotachykinin gene-I mRNA-encoding tachykinins. AB - Although the tachykinins substance P (SP) and neurokinin A have been largely localized to neurons, eosinophils have also been shown to express these peptides. Our aim was to determine whether rat alveolar macrophages (AM) express preprotachykinin gene-I (PPT-I) mRNA that encodes these tachykinins and to examine expression during inflammation. PPT-I mRNA was detected by reverse transcription (RT)-polymerase chain reaction (PCR) in AM and brain (control) but not in peritoneal macrophages. Northern analysis showed that PPT-I mRNA was induced two- to fourfold by in vivo treatment of rats with intratracheal lipopolysaccharide (LPS) and in vitro after 4 h of exposure to LPS. This increase was inhibited by dexamethasone. In situ RT-PCR and immunocytochemistry further confirmed that AM express PPT-I mRNA and SP-like immunoreactivity, respectively, which was enhanced by LPS treatment. A 1.3-kb transcript consistent with PPT-I mRNA was detected by Northern analysis of bronchoalveolar lavage neutrophils. Therefore, rat AM express PPT-I mRNA that is upregulated in AM by LPS and is attenuated by dexamethasone. PPT-I mRNA was also detected in lung neutrophils. PMID- 9374738 TI - Expression and regulation of gamma-glutamyl transpeptidase-related enzyme in tracheal cells. AB - Glutathione plays an essential role in protecting the pulmonary system from toxic insults. gamma-Glutamyl transpeptidase-related enzyme (GGT-rel) is a novel protein capable of cleaving the gamma-glutamyl peptide bond of glutathione and of converting leukotriene C4 to leukotriene D4. A rat homologue of GGT-rel was identified and was found to be highly expressed in cultures of differentiating rat tracheal epithelial (RTE) cells. The 2.6-kb cDNA predicts a 572-amino acid protein with 79% identity to human GGT-rel. GGT-rel was weakly expressed in normal trachea but was strongly induced by epidermal growth factor in cultures of RTE cells. GGT-rel was also highly expressed in lung tumors induced by inhalation of isobutyl nitrite. These results demonstrate that GGT-rel 1) is expressed in normal tracheal cells, 2) can be induced by epidermal growth factor, and 3) is elevated after chemical exposure. The induction of high levels of GGT-rel may play an important role in protecting the lung from oxidative stress or other toxic insults. PMID- 9374739 TI - Induction of aquaporin 3 by corticosteroid in a human airway epithelial cell line. AB - Although aquaporin 3 (AQP3) is expressed in many tissues in the kidney, gastrointestinal tract, lung, and other organs, its physiological significance in the body still remains to be clarified. To determine whether AQP3 expression is regulated by dexamethasone in human airway epithelium, we studied mRNA expression, protein expression, and water permeability of the cell membrane in a human airway epithelial cell line (A549 cells). Expression of AQP3 mRNA and protein was studied by Northern blot analysis and immunoblot analysis, and osmotic water permeability (Pf) was measured by a stopped-flow light-scattering method. Expression of AQP3 mRNA and protein was detectable in A549 cells and was stimulated by dexamethasone. Pf in A549 cells after incubation with dexamethasone was approximately 2.5-fold greater than that without dexamethasone. Moreover, this dexamethasone-induced increase in Pf was inhibited after treatment with HgCl2. In conclusion, the present study shows that A549 cells express AQP3 and that dexamethasone upregulates the expression of AQP3 and increases the water permeability of the cell membrane. Dexamethasone-regulated AQP3 expression might be important in certain forms of pulmonary diseases accompanied by airway hypersecretion that are treated by corticosteroid administration. PMID- 9374740 TI - Activated eosinophils elicit substance P release from cultured dorsal root ganglion neurons. AB - This study was performed to test the hypothesis that activated eosinophils or their secretory products can directly stimulate sensory neurons to release their neuropeptides. Neurons derived from neonatal rat dorsal root ganglia (DRG), which synthesize and store sensory neuropeptides, were placed in primary cell culture and were exposed to eosinophils or their bioactive mediators. The resultant release of substance P (SP) was measured by enzyme-linked immunosorbent assay and was expressed as a percent (mean +/- SE) of total neuronal SP content. Eosinophils were isolated from human volunteers with a history of allergic rhinitis and/or mild asthma and were activated by incubation with cytochalasin B (5 micrograms/ml) and N-formyl-methionyl-leucyl-phenylalanine (FMLP, 1 microM). Activated eosinophils [6 x 10(6)/ml, suspended in Hanks' buffered salt solution (HBSS)] applied to cultured DRG neurons for 30 min increased basal SP release 2.4 fold compared with HBSS-exposed neurons (activated eosinophils 11.10 +/- 2.48% vs. HBSS 4.59 +/- 0.99%; P = 0.002), whereas neither nonactivated eosinophils nor cytochalasin B and FMLP in HBSS influenced SP release. Additional cultured DRG neurons were exposed to soluble products made by eosinophils. Compared with SP release under control conditions (2.37 +/- 0.34%), major basic protein (MBP) increased release in a concentration-related fashion (e.g., 3 microM MBP: 6.23 +/ 0.67%, P = 0.006 vs. control), whereas neither eosinophil cationic protein (3 microM), eosinophil-derived neurotoxin (3 microM), leukotriene D4 (500 nM), platelet-activating factor (100 nM), nor H2O2 (100 microM) affected SP release. These studies demonstrate that activated eosinophils can stimulate cultured DRG neurons directly and suggest that MBP may be the responsible mediator. PMID- 9374741 TI - Molecular analysis of blood vessel formation and disease. AB - Blood vessels affect the quality of life in many ways. They provide an essential nutritive function during growth and repair of tissues but, on the other hand, can become affected by disorders or trauma, resulting in bleeding, thrombosis, arterial stenosis, and atherosclerosis. Three molecular systems, the vascular endothelial growth factor (VEGF) system, the plasminogen system, and the coagulation system, have been implicated in the formation and pathobiology of blood vessels. This review focuses on the role of these systems in these processes. Recent gene-targeting studies have identified VEGF as a potent modulator of the formation of endothelial cell-lined channels. Somewhat unanticipated, the initiator of coagulation is not only involved in the control of hemostasis but also in the maturation of a muscular wall around the endothelium. With different murine models of cardiovascular disease, a pleiotropic role of the plasminogen system was elucidated in thrombosis, in arterial neointima formation after vascular wound healing and allograft transplantation, in atherosclerosis, and in the formation of atherosclerotic aneurysms. Surprisingly, tissue-type plasminogen activator is also involved in brain damage after ischemic or neurotoxic insults. The insights from these gene targeting studies have formed the basis for designing gene therapy strategies for restenosis and thrombosis, which have been successfully tested in these knockout models. PMID- 9374742 TI - Molecular remodeling of cardiac contractile function. AB - A number of techniques are now available that allow the contractile apparatus of the heart to be altered in a defined manner. This review focuses on those approaches that result in germ-line transmission of the remodeling event(s). Thus the desired modifications can be propagated stably throughout multiple generations and result in the creation of stable, new animal models. Necessarily, such stable changes need to be performed at the level of the genome, and two distinct but complementary approaches have been developed: transgenesis and gene targeting. Each results in the stable modification of the mammalian genome. Via gene targeting or gene ablation of sequences encoding various components of the sarcomere, the contractile apparatus of the heart can be altered dramatically. Ablating a gene may lead to a loss in function, which can help establish a function of the candidate sequence. Gene targeting can also be used to effect changes in the sequences encoding a functional domain of the contractile protein or at a single-amino acid residue, resulting in the establishment of precise structure-function relationships. With the use of transgenesis, the contractile apparatus of the heart can also be significantly remodeled. These approaches are rapidly creating a group of animals in which altered contractile protein complements will lead to a fundamental understanding of the structure-function relationships that underlie the function of the heart at the molecular, biochemical, whole organ, and whole animal levels. PMID- 9374743 TI - A role for neuropeptide Y in rat iridial arterioles. AB - A role for neuropeptide Y (NPY) in neurotransmission in rat iridial arterioles has been investigated. Reverse transcription-polymerase chain reaction analysis has demonstrated mRNA expression for both Y1 and Y2 receptors in the superior cervical ganglion and iris. The Y1 agonist [Leu31,Pro34]NPY caused a dose dependent constriction of iris arterioles (50% effective concentration of 10(-8) M), but, at low concentrations (10(-9) and 10(-10) M), it failed to potentiate either submaximal responses to norepinephrine (10(-6) M) or submaximal, noradrenergic responses to nerve stimulation. In contrast, 10(-7) M [Leu31,Pro34]NPY potentiated submaximal, noradrenergic responses to nerve stimulation (10 Hz, < or = 1 s) and to a concentration of norepinephrine (10(-7) M) which produced only small contractions. The Y1 antagonist 1229U91 blocked contractions induced by [Leu31,Pro34]NPY. Stimulation of the nerves for longer periods (10 or 20 Hz; 5, 30, or 60 s) revealed a component of the response which was reduced by 1229U91. This component was not apparent after brief stimuli (10 Hz, < or = 1 s), even when opposing receptor pathways were blocked. The Y2 agonist N-acetyl-[Leu28,Leu31]NPY24-36 had little effect on arterioles preconstricted with either high potassium or an alpha 2-adrenoceptor agonist, or on nerve-mediated contractions. Results suggest that NPY, released from sympathetic nerves during long-duration, high-frequency stimulation, activates Y1 receptors on iris arterioles to produce vasoconstriction and to potentiate responses to low concentrations of norepinephrine. PMID- 9374744 TI - Age effects on interrelationships between lung volume and heart rate during standing. AB - To determine the effects of aging and posture on the relationship between respiration and heart rate (HR), we collected 5 min of lung volume and R-R interval data from 7 young (27 +/- 3 yr, mean +/- SD) and 10 old (69 +/- 6 yr) healthy humans during spontaneous breathing while they were supine (SU) and standing (ST). Lung volume and HR power spectra and transfer functions between lung volume and HR were estimated. Age and position effects and age-position interactions were determined by analysis of variance for repeated measures. Older subjects had a lower and more variable respiration rate (P < 0.03, P < 0.04), but both age groups exhibited decreased rate of respiration and increased tidal volume with ST (P < 0.05, P < 0.005). ST decreased lung volume-to-HR transfer function magnitude in both groups (P < 0.07). The more marked age-related differences were in phase angle. Both SU and ST phase angles were greater in older subjects (P < 0.003). ST decreased phase angle in young but increased phase angle in older subjects (P < 0.001). In conclusion, respiration, and respiration HR interrelationships are altered by aging, with increased time delays between lung volume and HR and altered relationships with ST. PMID- 9374745 TI - Substantial cardiac parasympathetic activity exists during heavy dynamic exercise in dogs. AB - We investigated the extent of functional parasympathetic and sympathetic activity to the heart at rest and during mild to heavy dynamic exercise in conscious dogs. The animals were chronically instrumented to monitor mean arterial pressure (MAP), heart rate (HR), and terminal aortic blood flow (TAQ) and trained to run on a motor-driven treadmill. MAP, HR, and TAQ were monitored at rest and during steady-state dynamic exercise ranging from mild [3.2 kilometers per hour (kph), 0% grade] to heavy exercise (8 kph, 15% grade). Experiments were performed before and after blocking the effects of either the parasympathetic nerves (atropine 0.2 mg/kg i.v.) or sympathetic nerves (atenolol 2.0 mg/kg i.v.) to the heart. In addition, blood samples were taken at rest and at steady state during exercise, and plasma levels of vasopressin and renin activity were assessed. At rest and during all levels of exercise, muscarinic cholinergic receptor blockade caused a marked increase in HR over control (saline treated) levels with little effect on MAP or TAQ. beta-Adrenergic receptor blockade had no significant effect on HR at rest and during mild exercise. At moderate to heavy workloads, beta-receptor blockade significantly reduced MAP, HR, and TAQ and increased plasma vasopressin levels. We conclude that, even during heavy dynamic exercise, significant functional parasympathetic tone to the heart exists. Thus, over a wide range of exercise workloads, HR is under the tonic control of both sympathetic and parasympathetic nerves. PMID- 9374746 TI - Pelvic nerve stimulation-induced pressor responses in corpus cavernosum of anesthetized dogs. AB - To analyze the mechanism of penile erection and pathogenesis of impotence, pressures in the corpus cavernosum in anesthetized dogs were measured. Pelvic nerve stimulation produced pressor responses in a frequency-dependent manner. Intravenous injections of NG-nitro-L-arginine, a nitric oxide (NO) synthase inhibitor, dose dependently attenuated the response, and the inhibition was reversed by intravenous injection of L-arginine but not of D-arginine. The response was also inhibited by NG-nitro-L-arginine injected into the corpus cavernosum, the potency being approximately 10 times of that applied intravenously. The intracavernous injection of L-arginine restored the response. NG, NG-dimethylarginine, an endogenous NO synthase inhibitor, dose dependently attenuated the stimulation-induced response, which was restored by an intracavernous injection of L-arginine. An intravenous injection of hexamethonium abolished the pressor response to nerve stimulation, whereas phentolamine and atropine did not significantly alter the response. These findings suggest that an increase in intracavernous pressure caused by pelvic nerve stimulation in anesthetized dogs is mediated by NO liberated from postganglionic neurons that originate in the ganglion located in the vicinity of corpus cavernosum. PMID- 9374747 TI - Contribution of asynchrony and nonuniformity to mechanical interaction in normal and stunned myocardium. AB - In anesthetized pigs, we investigated whether asynchrony (delta T) and nonuniformity (regional differences) in contractility (delta E) could describe the interaction between normal and stunned myocardium. Mechanical interaction was evaluated by regional postsystolic work (PSW) before and after production of stunning by a 5-min occlusion of the left circumflex coronary artery [LCX (LCX stunning)] and a subsequent 10-min occlusion of the left anterior descending coronary artery [LAD (LAD stunning)]. delta T and delta E were intensified by intracoronary (LAD) infusions of dobutamine. From regional end-systolic pressure segment length relationships, systolic segment shortening (SS), end-systolic elastance (E), external work (EW), and PSW were determined. LCX stunning decreased SSLCX from 14 +/- 2 (mean +/- SE, n = 9) to 10 +/- 2% and ELCX from 103 +/- 25 to 52 +/- 7 mmHg/mm, whereas the LAD region was unaffected. EWLCX decreased from 165 +/- 16 to 138 +/- 20 mmHg.mm, whereas PSWLCX increased from -4 +/- 6 to 8 +/- 3 mmHg.mm. Additional LAD stunning reduced SSLAD from 16 +/- 2 to 9 +/- 3% and ELAD from 79 +/- 10 to 31 +/- 6 mmHg/mm, without affecting SSLCX and ELCX. In the normal myocardium, PSWLAD increased and PSWLCX decreased, but, during local LAD dobutamine infusions after stunning, both PSWLCX and PSWLAD increased. In normal myocardium, the changes in PSWLCX could be described by delta T (65 +/- 11%) and delta E (37 +/- 15%). After stunning of the LAD area, the contribution of delta E increased to 55 +/- 14% at the expense of delta T (37 +/- 15%). Similar contributions of delta E (54 +/- 13%) and delta T (57 +/- 13%) were found when both the LCX and LAD distribution areas were stunned. In normal myocardium, both delta T and delta E modulate mechanical interaction, with the contribution of delta T exceeding that of delta E. In stunned myocardium, both factors contribute, but the contribution shifts in favor of delta E. PMID- 9374749 TI - Calcium transient alternans in blood-perfused ischemic hearts: observations with fluorescent indicator fura red. AB - Ischemia produces striking electrophysiological abnormalities in blood-perfused hearts that may be caused, in part, by effects of ischemia on intracellular calcium. To test this hypothesis, intracellular Ca2+ concentration ([Ca2+]i) transients were recorded from the epicardial surface of blood- and saline perfused rabbit hearts using the long-wavelength indicator Fura Red. Calcium transients were much larger than the movement artifact, representing up to 29% of the total signal. Switching the perfusate from saline to blood did not affect the time course of the transients or the apparent level of [Ca2+]i. Compartmentation of Fura Red fluorescence was estimated by exposure to Mn2+. The results were cytosol 60 +/- 3%, organelles 12 +/- 2%, and autofluorescence plus partly deesterified Fura Red 29 +/- 4%. [Ca2+]i transients were calibrated in situ by perfusion of the extracellular space with high-Ca2+ and Ca(2+)-free EGTA solutions. Peak systolic [Ca2+]i was 663 +/- 74 nM, and end-diastolic [Ca2+]i was 279 +/- 59 nm. Ischemia was produced by interruption of aortic perfusion for 2.5 min during pacing (150 beats/min). Ischemia produced broadening of the [Ca2+]i transient, along with beat-to-beat alternations in the peak systolic and end diastolic level of [Ca2+]i (calcium transient alternans). [Ca2+]i transient alternans occurred in 82% of blood-perfused hearts vs. 43% of saline-perfused hearts. The discrepancy between large and small transients (mean alternans ratio) was larger in the blood-perfused hearts (0.23 +/- 0.04 vs. 0.07 +/- 0.03, P = 0.005). These observations are important because of the apparent relationship of [Ca2+]i transient alternans to electrical alternans and arrhythmias during ischemia. PMID- 9374748 TI - Effects of ionic channel antagonists barium, cesium, and UL-FS-49 on vagal slowing of atrial rate in dogs. AB - In response to a brief vagal stimulus, the atrial rate initially slows, then transiently accelerates, and slows a second time. We determined the effects of three antagonists to two ionic channels on this characteristic triphasic pacemaker response. Brief bursts of vagal stimulation were delivered to anesthetized dogs, and atrial cycle lengths were recorded. Either barium, cesium, or UL-FS-49 was administered. Barium, which primarily blocks the acetylcholine sensitive potassium current (IK,ACh), attenuated the initial vagally induced bradycardia by > 50% without affecting the subsequent acceleration or the secondary slowing. Cesium and UL-FS-49 [both of which primarily block the pacemaker current (If)] did not affect the initial vagal slowing of atrial rate but abolished the acceleratory portion of the response. The secondary slowing was abolished by cesium but not by UL-FS-49. We conclude that the initial rapid atrial response to acetylcholine is mediated mainly by the IK,ACh, with little contribution from the If. The subsequent acceleration is mediated by activation of the If. PMID- 9374750 TI - Effects of insulin on glucose uptake by rat hearts during and after coronary flow reduction. AB - We tested the hypothesis that low-flow ischemia increases glucose uptake and reduces insulin responsiveness. Working hearts from fasted rats were perfused with buffer containing glucose alone or glucose plus a second substrate (lactate, octanoate, or beta-hydroxybutyrate). Rates of glucose uptake were measured by 3H2O production from [2-3H]glucose. After 15 min of perfusion at a physiological workload, hearts were subjected to low-flow ischemia for 45 min, after which they were returned to control conditions for another 30 min. Insulin (1 mU/ml) was added before, during, or after the ischemic period. Cardiac power decreased by 70% with ischemia and returned to preischemic values on reperfusion in all groups. Low-flow ischemia increased lactate production, but the rate of glucose uptake during ischemia increased only when a second substrate was present. Hearts remained insulin responsive under all conditions. Insulin doubled glucose uptake when added under control conditions, during low-flow ischemia, and at the onset of the postischemic period. Insulin also increased net glycogen synthesis in postischemic hearts perfused with glucose and a second substrate. Thus insulin stimulates glucose uptake in normal and ischemic hearts of fasted rats, whereas ischemia stimulates glucose uptake only in the presence of a cosubstrate. The results are consistent with two separate intracellular signaling pathways for hexose transport, one that is sensitive to the metabolic requirements of the heart and another that is sensitive to insulin. PMID- 9374751 TI - Cardiorenal epinephrine kinetics: evidence for neuronal release in the human heart. AB - There are experimental data suggesting that epinephrine (Epi) may act as a cotransmitter in sympathetic nerves, stimulating presynaptic beta 2-receptors and enhancing norepinephrine (NE) release. To examine neuronal Epi release, patients with congestive heart failure and hypertension and healthy subjects were examined with the isotope-dilution method. At baseline, small cardiac and renal Epi spillovers were found in patients. During intense supine exercise, cardiac NE and Epi spillovers increased concomitantly with similar magnitude, whereas no renal Epi spillover could be detected. Blockade of neuronal uptake 1 caused a consistent decrease in both cardiac and renal fractional extractions of NE and Epi. The present study demonstrates baseline cardiorenal Epi release in patients with congestive heart failure and renal Epi release in hypertensive patients. Furthermore, Epi is removed by neuronal uptake in both the heart and kidney, and cardiac Epi spillover increases during exercise. This study, in contrast to other results, provides evidence for cardiac neuronal Epi release. PMID- 9374752 TI - Arterial compliance increases after moderate-intensity cycling. AB - Exercise training elevates arterial compliance at rest, but the effects of acute exercise in this regard are unknown. This study investigated the effects of a single, 30-min bout of cycling exercise at 65% of maximal oxygen consumption on indexes of arterial compliance. Whole body arterial compliance determined noninvasively from simultaneous measurements of aortic flow and carotid pressure was elevated (66 +/- 26%) at 0.5 h postexercise (P = 0.04), followed by a decline to baseline 1 h after exercise. Aortic pulse-wave velocity, which is inversely related to compliance, was reduced (4 +/- 2%; P = 0.04) at 0.5 h postexercise. Pulse-wave velocity in the leg decreased by 10 +/- 4% at this time (P = 0.01). Mean arterial pressure was unchanged; however, central systolic blood pressure was reduced postexercise (P = 0.03). Cardiac output was elevated after exercise (P = 0.007) via heart rate elevation (P = 0.001), whereas stroke volume was unchanged. Total peripheral resistance was therefore reduced (P = 0.01) and would be expected to contribute to an elevation in arterial compliance. In conclusion, a single bout of cycling exercise increased whole body arterial compliance by mechanisms that may relate to vasodilation. PMID- 9374753 TI - L-citrulline conversion to L-arginine in sphenopalatine ganglia and cerebral perivascular nerves in the pig. AB - The presence of nitric oxide synthase (NOS), argininosuccinate synthetase (ASS), and argininosuccinate lyase (ASL) and their coexistence with NADPH-diaphorase (NADPHd), a marker for NOS, in the porcine sphenopalatine ganglia (SPG), pial veins, and the anterior cerebral arteries was examined using immunohistochemical and histochemical staining techniques. NOS-immunoreactive (I), ASS-I, and ASL-I fibers were found in pial veins and the anterior cerebral arteries. NOS, ASS, and ASL immunoreactivities were also found in neuronal cell bodies in the SPG. Almost all neuronal cell bodies in the SPG and nerve fibers in pial veins and the anterior cerebral arteries that were reactive to ASS, ASL, and NOS were also stained positively with NADPHd, suggesting that ASS, ASL, and NOS were colocalized in the same neurons in the SPG and perivascular nerves. With the use of in vitro tissue bath techniques, L-citrulline but not D-citrulline reversed inhibition of neurogenic vasodilation in isolated porcine pial veins produced by NOS inhibitors such as NG-nitro-L-arginine methyl ester. In the presence of L aspartate, L-arginine was synthesized from L-citrulline in homogenates of SPG and endothelium-denuded cerebral arteries and pial veins. These results provide evidence indicating that perivascular nerves in pial veins like cerebral arteries can convert L-citrulline to L-arginine for synthesizing nitric oxide. The conversion is most likely via an argininosuccinate pathway. PMID- 9374754 TI - Enhancement of spontaneous baroreflex by antisense c-fos oligonucleotide treatment in the NTS of the rat. AB - We evaluated the hypothesis that basal Fos protein at the nucleus tractus solitarii (NTS), the primary terminal site for baroreceptor afferents, exerts a tonic inhibitory modulation on the spontaneous baroreceptor reflex (BRR) control machinery, which is responsible for beat-to-beat regulation of resting systemic arterial pressure (SAP). In adult male Sprague-Dawley rats anesthetized and maintained with pentobarbital sodium, microinjection bilaterally into the caudal NTS of a 15-mer antisense oligonucleotide that targets against the initiation codon of c-fos mRNA (5'-129 to 143-3') significantly enhanced the spontaneous BRR response, as determined by transfer function analysis of SAP and heart rate signals. The same treatment also diminished baseline Fos-like immunoreactivity in the absence of acute cardiovascular perturbation. Control treatments with artificial cerebrospinal fluid, sense cDNA, or antisense oligonucleotides that either target against a different site of the c-fos mRNA (5'-135 to 149-3') or with three mismatched nucleotides in the antisense sequence, were ineffective. These observations support the notion that, under minimal cardiovascular perturbation, basal expression of Fos protein in the NTS may represent an early step in the cascade of intracellular events that leads to long-term inhibitory modulation of beat-to-beat baroreflex control of blood pressure. PMID- 9374755 TI - Complexity of middle cerebral artery blood flow velocity: effects of tilt and autonomic failure. AB - We examined spectral fractal characteristics of middle cerebral artery (MCA) mean blood flow velocity (MFV) and mean arterial blood pressure adjusted to the level of the brain (MAPbrain) during graded tilt (5 min supine, -10 degrees, 10 degrees, 30 degrees, 60 degrees, -10 degrees, supine) in eight autonomic failure patients and age- and sex-matched controls. From supine to 60 degrees, patients had a larger drop in MAPbrain (62 +/- 4.7 vs. 23 +/- 4.5 mmHg, P < 0.001; means +/- SE) and MFV (16.4 +/- 3.8 vs. 7.0 +/- 2.5 cm/s, P < 0.001) than in controls. From supine to 60 degrees, there was a trend toward a decrease in the slope of the fractal component (beta) of MFV (MFV-beta) in both the patients and the controls, but only the patients had a significant decrease in MFV-beta (supine: patient = 2.21 +/- 0.18, control = 1.99 +/- 0.60; 60 degrees: patient = 1.46 +/- 0.24, control = 1.62 +/- 0.19). The beta value of MAPbrain (MAPbrain-beta; 2.19 +/- 0.05) was not significantly different between patients and controls and did not change with tilt. High and low degrees of regulatory complexity are indicated by values of beta close to 1.0 and 2.0, respectively. The increase in fractal complexity of cerebral MFV in the patients with tilt suggests an increase in the degree of autoregulation in the patients. This may be related to the drop in MAPbrain. The different response of MFV-beta compared with that of MAPbrain-beta also indicates that MFV-beta is related to the regulation of cerebral vascular resistance and not systemic blood pressure. PMID- 9374756 TI - Flow- and agonist-mediated nitric oxide- and prostaglandin-dependent dilation in spinal arteries. AB - Isolated rabbit spinal resistance-sized arteries (approximately 100 microns in diameter and approximately 3 mm long) were cannulated at both ends with glass micropipettes and perfused at constant pressure (60 mmHg). An increase of flow rate corresponding to a change of pressure gradient (delta P) ranging from 0 to 20 mmHg produced a flow-dependent vasodilation. Treatment with 50 microM aspirin or 10 microM indomethacin produced a significant reduction of the flow-dependent vasodilation only at delta P of 5 mmHg. In contrast, treatment with N omega-nitro L-arginine methyl ester (L-NAME, 30 microM) produced no significant change. In the presence of 10 microM indomethacin, however, 30 microM L-NAME caused a marked decrease in the arterial diameter at delta P of 5 mmHg, which was completely reversed with additional administration of 1 mM L-arginine. Acetylcholine (ACh) produced a dose-dependent increase in the arterial diameter. The ACh-induced vasodilation was significantly reduced by 10 microM indomethacin or 50 microM aspirin and partially suppressed by 30 microM L-NAME. Pretreatment with both indomethacin and L-NAME completely reduced the ACh-induced vasodilation. In the presence of 10 microM indomethacin, additional treatment with 1 mM L-arginine significantly reversed the L-NAME-induced inhibition of the ACh-mediated vasodilation. Endothelial removal with Triton X-100 significantly reduced the ACh induced vasodilation. Isocarbacyclin (a stable prostaglandin I2 analogue), prostaglandin E2, and arachidonic acid caused a dose-dependent dilation in the small arteries. These findings suggest that prostanoids play a major role in the flow- or ACh-induced vasodilation in the rabbit spinal resistance-sized small arteries. PMID- 9374757 TI - Effects of high glucose on vascular endothelial growth factor expression in vascular smooth muscle cells. AB - Vascular endothelial growth factor (VEGF), in addition oto its growth-promoting effects on endothelial cells, can also increase vascular permeability and monocyte migration. It has therefore been implicated in the pathogenic neovascularization associated with diabetic retinopathy and atherosclerosis. However, the factors regulating VEGF expression in the vascular wall are not fully understood. In this study, we examined the regulation of VEGF expression in vascular smooth muscle cells (VSMC) by hyperglycemia as well as by angiotensin II (ANG II). We also examined whether the 12-lipoxygenase (12-LO) product 12 hydroxyeicosatetraenoic acid (12-HETE) can alter VEGF expression, since 12-LO products of arachidonic acid have angiogenic properties, and ANG II as well as high glucose (HG, 25 mM) can increase 12-LO activity and expression in VSMC. Studies were carried out in human (HSMC) or porcine VSMC (PSMC), which were cultured for at least two passages under normal glucose (NG, 5.5 mM) or HG conditions. HG culture alone increased the expression of VEGF mRNA and protein in both HSMC and PSMC. Furthermore, ANG II treatment significantly induced VEGF mRNA and protein expression only in VSMC cultured in HG and not NG. In addition, 12 HETE significantly increased VEGF mRNA and protein expression in HSMC cultured in NG as well as in HG. Cells cultured in HG also secreted significantly greater amounts of VEGF into the culture medium. These results suggest that elevated VEGF production under HG conditions may play a role in the accelerated vascular disease observed in diabetes. PMID- 9374758 TI - Myocardial dysfunction is associated with activation of Na+/H+ exchange immediately during reperfusion. AB - Amiloride analogs block Na+/H+ exchange and thereby protect the heart from myocardial ischemia-reperfusion injury. It is unclear whether drugs must be present before ischemia to be cardioprotective. After 60 min of global ischemia in the coronary-perfused right ventricular wall (RVW), as little as 1 min of exposure to dimethyl amiloride (DMA) immediately at the time of reperfusion protected the RVW. Delaying the drug attenuated the cardioprotection. If DMA was introduced in an ischemic solution near the end of ischemia, the cardioprotective effects were augmented. If the drug was washed out of the RVW vascular space before ischemia, cardioprotection was not observed. In contrast, in whole hearts, preischemic perfusion of the drug was necessary for cardioprotection and the cardioprotection remained even if the drug was washed out before ischemia. We conclude that Na+/H+ exchange is active and contributes to contractile dysfunction during the first seconds of reperfusion. This is difficult to detect in the perfused whole heart, and the washout data suggest that this may be due to a limitation in drug delivery across the vascular wall. The data also suggest that the exchanger is not as active during ischemia itself as it is during reperfusion. PMID- 9374759 TI - Baroreflex sensitivity and heart rate variability in conscious rats with myocardial infarction. AB - The baroreflex sensitivity (BRS) and the heart rate variability (HRV) were studied in conscious rats after myocardial infarction (MI; induced by coronary artery ligation) and after sham operation (SH). BRS was determined by linear regression of R-R interval vs. arterial pressure changes induced by nitroprusside or methoxamine (intravenous bolus). HRV was calculated from 3-min electrocardiogram recordings. Left ventricular end-diastolic pressure and plasma atrial natriuretic peptide were increased after MI; plasma norepinephrine and basal heart rate (HR) remained unchanged. At 3 and 28 days after MI, BRS was reduced as indicated by decreased reflex bradycardia (RB) (MI, 0.66 +/- 0.13 and 0.78 +/- 0.07 ms/mmHg; SH, 1.27 +/- 0.16 and 1.48 +/- 0.14 ms/mmHg, respectively; P < 0.05 MI vs. SH). At 56 days after MI, BRS was normalized. RB was unaffected by atropine 3 and 28 days after MI but reduced in all other groups. The increase of basal HR by atropine 3 and 28 days after MI was less than in all other groups. HRV (SD of mean N-N interval, coefficient of variance, low- and high-frequency power; studied at 28 and 56 days) was similar in all groups. It is concluded that BRS is transiently depressed in rats with left ventricular dysfunction after MI probably due to a reduced reflex vagal activity. Even though basal HR and HRV are unchanged after MI, a temporary attenuation of tonic vagal activity is unmasked after autonomic blockade. PMID- 9374760 TI - Estrogen regulates myogenic tone in pressurized cerebral arteries by enhanced basal release of nitric oxide. AB - Second-order middle cerebral arteries (135.0 +/- 4.6 microns ID) from male, female, ovariectomized female (no endogenous estrogen), and estrogen-treated ovariectomized female Sprague-Dawley rats were harvested and mounted in a pressure myograph. Myogenic response was recorded over a pressure range of 10-100 mmHg and was repeated in the presence of N omega-nitro-L-arginine methyl ester (L NAME; 2 x 10(-4) M, an inhibitor of nitric oxide (NO) synthase, and after endothelium removal, to examine the contribution of NO to net myogenic tone. With intact endothelium, there were no differences in myogenic tone between the groups, but in the presence of L-NAME and after endothelium removal, estrogen exposed vessels developed significantly greater tone at-high transmural pressure. There were no differences in sensitivity to sodium nitroprusside, an NO donor, or A-23187, a calcium ionophore. These results suggest an increase in basal release of NO in cerebral arteries exposed to estrogen, without change in NO sensitivity or maximally stimulated NO release. PMID- 9374761 TI - Decreased intracellular pH is not due to increased H+ extrusion in preconditioned rat hearts. AB - Ischemic preconditioning reduces intracellular acidification during a subsequent, prolonged period of ischemia. This may reflect decreased anaerobic glycolysis or increased H+ efflux. To distinguish between these hypotheses, we monitored intracellular and extracellular pH during a sustained period of ischemia to determine whether the preconditioned hearts had increased H+ efflux compared with nonpreconditioned hearts. At the end of 20 min of ischemia, intracellular pH in nonpreconditioned hearts was 5.90 +/- 0.08 and extracellular pH was 5.51 +/- 0.21, whereas in preconditioned hearts, intracellular pH was 6.50 +/- 0.06 and extracellular pH was 6.62 +/- 0.06. To investigate whether an Na+/H+ exchange inhibitor would alter the reduced acidification during ischemia, we preconditioned hearts with and without dimethylamiloride (DMA). Intracellular pH during ischemia was similar in preconditioned hearts with and without DMA treatment (pH 6.42 +/- 0.02 vs. 6.45 +/- 0.03, respectively). These data do not support the hypothesis that enhanced proton efflux is responsible for the more alkaline intracellular pH during sustained ischemia in preconditioned hearts. PMID- 9374762 TI - Contribution of angiotensin-converting enzyme to the cardiac metabolism of bradykinin: an interspecies study. AB - The role of angiotensin-converting enzyme (ACE) in the metabolism of bradykinin (BK) has been studied in several tissues. However, and contrary to angiotensin I, the metabolism of BK at the cardiac level has not been investigated. In this study, we define the participation of ACE in the carboxy-terminal degradation of BK in heart membranes of the dog, human, rabbit, and rat. The calculation of the kinetic parameters characterizing the metabolism of BK and the generated des-Arg9 BK can be summarized as follows: the half-life (t1/2) of BK [dog (218 +/- 32 s) > human (143 +/- 9 s) = rat (150 +/- 4 s) > rabbit (22 +/- 2 s)] and of des-Arg9-BK [dog (1,042 +/- 40 s) > human (891 +/- 87 s) > rat (621 +/- 65 s) > rabbit (89 +/ 8 s)] both showed significant differences according to species. Enalaprilat, an ACE inhibitor, significantly prevented the rapid degradation of BK and des-Arg9 BK in all species studied, whereas retrothiorphan, a neutral endopeptidase inhibitor, and losartan, an angiotensin II type I receptor antagonist, did not affect this metabolism. The relative importance of ACE in the cardiac metabolism of BK was species related: dog (68.4 +/- 3.2%) = human (72.2 +/- 2.0%) > rabbit (47.7 +/- 5.0%) = rat (45.3 +/- 3.9%). ACE participation in the metabolism of des Arg9-BK was as follows: rabbit (57.0 +/- 4.0%) > dog (39.9 +/- 8.8%) = human (25.4 +/- 5.5%) = rat (36.0 +/- 7.0%). The participation of cardiac kininase I (carboxypeptidase M) in the transformation of BK into des-Arg9-BK was minor: human (2.6 +/- 0.1%) > dog (0.9 +/- 0.1%) = rabbit (1.0 +/- 0.1%) = rat (1.0 +/- 0.1%). These results demonstrate that ACE is the major BK-degrading enzyme in cardiac membranes. However, the metabolism of exogenous BK by heart membranes is species dependent. Our observations could explain some discrepancies regarding the contribution of kinins in the cardioprotective effects of ACE inhibitors. PMID- 9374763 TI - Microvascular blood flow resistance: role of endothelial surface layer. AB - Observations of blood flow in microvascular networks have shown that the resistance to blood flow is about twice that expected from studies using narrow glass tubes. The goal of the present study was to test the hypothesis that a macromolecular layer (glycocalyx) lining the endothelial surface contributes to blood flow resistance. Changes in flow resistance in microvascular networks of the rat mesentery were observed with microinfusion of enzymes targeted at oligosaccharide side chains in the glycocalyx. Infusion of heparinase resulted in a sustained decrease in estimated flow resistance of 14-21%, hydrodynamically equivalent to a uniform increase of vessel diameter by approximately 1 micron. Infusion of neuraminidase led to accumulation of platelets on the endothelium and doubled flow resistance. Additional experiments in untreated vascular networks in which microvascular blood flow was reduced by partial microocclusion of the feeding arteriole showed a substantial increase of flow resistance at low flow rates (average capillary flow velocities < 100 diameters/s). These observations indicate that the glycocalyx has significant hemodynamic relevance that may increase at low flow rates, possibly because of a shear-dependent variation in glycocalyx thickness. PMID- 9374764 TI - Autoactivity of A5 neurons: role of subthreshold oscillations and persistent Na+ current. AB - A5 noradrenergic neurons play a key role in autonomic regulation, nociception, and respiration. The purpose of the present experiments was to characterize some of the intrinsic properties of A5 cells in vitro. Whole cell recordings were obtained from 85 spinally projecting neurons of the ventrolateral pons of neonate rats. Immunohistochemistry showed that 60% of the ventrolateral pontine cells were noradrenergic. Eighty percent of A5 neurons were spontaneously active (0.1 5.5 spikes/s). Their discharge rate was unchanged by a mixture of synaptic blockers that eliminated postsynaptic potentials (PSPs). The nonnoradrenergic cells could not be distinguished from A5 cells on the basis of discharge rate, action potential duration, inward rectification, input resistance, or accommodation. A5 cells displayed subthreshold irregular oscillations of the membrane potential (main frequency component 0.5-2 Hz). These oscillations were unchanged in the presence of low external Ca(2+)-high Mg2+ and were very reduced by hyperpolarizing the cells below -65 mV. The oscillations were partially attenuated by 1 microM tetrodotoxin (TTX) and were eliminated by reducing external Na+ (27 mM). Stepping the membrane potential from -65 to -50 mV for 200 ms revealed the presence of a transient and a persistent inward current that were both blocked by 0.1 microM TTX or by extracellular Na+ reduction. In conclusion, most A5 neurons are spontaneously active in vitro. They display irregular subthreshold membrane potential oscillations generated by voltage-activated conductances that include a persistent TTX-sensitive Na+ current. Most of the activity of A5 cells appears due to intrinsic properties rather than to synaptic inputs. PMID- 9374765 TI - Alpha 2-adrenergic autoreceptors in A5 and A6 neurons of neonate rats. AB - A5 noradrenergic neurons control sympathetic outflow, nociception, and respiration. The presence of alpha 2-adrenergic receptors (alpha 2-ARs) in A5 cells has been suggested by immunohistochemistry. In the present experiments, we analyze the response of spinally projecting A5 cells to alpha 2-AR agonists, and we compare it with that of locus ceruleus (A6) neurons. Whole cell recordings were obtained from 52 spinally projecting neurons in the ventrolateral pons of neonate rats. Immunohistochemistry showed that 60% of the recorded cells were A5 cells. In A5 cells clamped at -55 mV, norepinephrine (NE) in the presence of the alpha 1-AR antagonist prazosin produced a Ba(2+)-sensitive outward current (20.4 +/- 2.6 pA; n = 28). The alpha 2-AR-induced current reversed at the K+ equilibrium potential (EK) at three different extracellular K+ concentrations. Replacement of 82% of the extracellular Na concentration with N-methyl-D glucamine did not change the reversal potential. The 19 presumably noncatecholaminergic neurons responded weakly or not at all to NE (2.5 +/- 0.6 pA outward current). Pontospinal A6 neurons (n = 11) were also recorded. Six A6 cells displayed large tetrodotoxin (TTX)-resistant membrane oscillations. In these cells, the current induced by alpha 2-AR stimulation did not reverse over the voltages tested (-50 to -130 mV) or reversed at potentials more negative than EK (less than -114 mV). In A6 neurons that did not display large oscillations (n = 5), the alpha 2-AR-induced current reversed at or close to the EK (-90 +/- 1.6 mV). In conclusion, A5 cells, like locus ceruleus neurons, have alpha 2-ARs that may function as autoreceptors. In both cases, alpha 2-AR activation increases an inwardly rectifying K+ conductance. In A5 cells, we found no evidence that alpha 2-AR activation decreases a resting Na+ conductance. The inhibition of A5 cells by clonidine and other agents with alpha 2-AR agonist activity is likely to contribute to the ability of these drugs to decrease sympathetic tone and arterial pressure. PMID- 9374766 TI - Elevated right atrial pressure does not reduce collateral blood flow to ischemic myocardium. AB - Right atrial pressure (RAP) may become substantially elevated during heart failure and has been reported to reduce collateral flow to the ischemic myocardium of isolated hearts. The effect of elevated RAP on blood flow to collateral-dependent and normal myocardium of in situ hearts was studied in 20 open-chest anesthetized dogs with acute occlusion of the left anterior descending coronary artery. Regional myocardial blood flow was measured with radioactive microspheres while RAP was elevated by restricting right ventricular (RV) outflow with constant aortic pressure. Increasing RAP from 3.8 +/- 0.5 to 21.5 +/- 0.8 and then to 34.3 +/- 0.9 mmHg did not reduce blood flow to any transmural region of LV normal or collateral-dependent myocardium. Further elevation of RAP to 49.3 +/- 1.1 mmHg reduced subepicardial but not subendocardial collateral flow. Blood flow to normal RV increased. Retrograde flow and peripheral coronary pressure increased as RAP was elevated. Previously injected 11-micron microspheres were present in the retrograde flow when RAP was elevated; thus retrograde capillary flow contributed to the retrograde flow. The results explain discrepancies among previous reports, and they are consistent with a waterfall phenomenon in the coronary collateral circulation. PMID- 9374767 TI - Protein, not adenosine or adenine nucleotides, mediates platelet decrease in endothelial permeability. AB - Platelets and platelet-conditioned medium (PCM) decrease endothelial protein permeability in vitro. Adenosine and a > 100-kDa protein have previously been implicated as the soluble factors released from platelets that decrease endothelial permeability. The objective of this study was to further investigate the role of adenosine in this platelet response. Measurements of adenosine and its precursor adenine nucleotides by high-performance liquid chromatography were correlated with the assessment of permeability by 125I-labeled albumin clearance and electrical resistance across endothelial cell monolayers derived from the bovine pulmonary artery. PCM contained micromolar concentrations of AMP, ADP, and ATP, but adenosine was below detectable levels (< or = 0.1 microM). Adenosine deaminase, an enzyme that converts adenosine to inactive inosine, or an adenosine receptor antagonist did not block the platelet- or PCM-mediated decrease in endothelial permeability. A < 3-kDa fraction of PCM that contained micromolar concentrations of AMP and ADP did not affect endothelial permeability, whereas a > 3-kDa fraction that contained much reduced levels of AMP and ADP significantly decreased permeability. This activity of PCM was sensitive to insoluble trypsin. This study rules out adenosine and adenine nucleotides as primary factors in the platelet-induced decrease in endothelial permeability and suggests that the active factor is a protein. PMID- 9374768 TI - Reduced L-type calcium current in ventricular myocytes from endotoxemic guinea pigs. AB - The circulatory response to gram-negative sepsis and its experimental counterpart, endotoxemia, includes a profound dysfunction in myocardial contractility that is resident to the myocyte and associated with reduced systolic free intracellular Ca2+ concentration ([Ca2+]i). We explored the possibility that decreased systolic [Ca2+]i in endotoxemic myocytes is correlated with reduced L-type Ca2+ current (ICa,L). Ventricular myocytes were isolated from guinea pigs 4 h after an intraperitoneal injection of Escherichia coli lipopolysaccharide (LPS; 4 mg/kg). Membrane potentials and Ca2+ currents were measured using whole cell patch-clamp methods. The action potential duration of endotoxemic myocytes was significantly shorter than control values (time to 50% repolarization: LPS, 314 +/- 23 ms; control, 519 +/- 36 ms, P < 0.05). Correspondingly, endotoxemic myocytes demonstrated significantly reduced peak ICa,L density (3.5 +/- 0.2 pA/pF) and Ba2+ current (IBa) density (7.3 +/- 0.5 pA/pF) compared with respective values of control myocytes (ICa,L) density 6.1 +/ 0.3 pA/pF, IBa density 11.3 +/- 0.8 pA/pF; P < 0.05). Endotoxemia-induced reduction in peak ICa,L could not be attributed to alterations in current-voltage relationships, steady-state activation and inactivation, or recovery from inactivation. The beta-adrenoceptor agonist isoproterenol, but not the Ca2+ channel activator BAY K 8644, reversed the LPS-induced reduction in peak ICa,L, cell contraction, and systolic [Ca2+]i. These data demonstrate that part of the host response to endotoxemia involves diminished sarcolemmal ICa,L of ventricular myocytes. PMID- 9374769 TI - Gender differences in endothelium-dependent relaxations do not involve NO in porcine coronary arteries. AB - Experiments were designed to determine whether normal fluctuations in endogenous sex steroid hormones and/or gender affect endothelium-dependent relaxations in coronary arteries, and, if so, to identify endothelium-derived factors contributing to these differences. Coronary arteries from sexually mature, gonadally intact male and female pigs or ovariectomized pigs were prepared either for study of isometric force in organ chambers or for measurement of prostanoids and activity of nitric oxide (NO) synthase. In organ chamber studies, neither the magnitude nor the sensitivity of endothelium-dependent relaxations correlated with endogenous estrogen or progesterone in female pigs. However, relaxations to bradykinin and UK-14304 were significantly greater and/or shifted leftward in arterial rings from female compared with male pigs. Indomethacin (10(-5) mol/l) increased endothelium-dependent relaxations only in arteries from male pigs. N(G) monomethyl-L-arginine reduced endothelium-dependent relaxations to a similar extent in coronary arteries from either sex. Neither production nor response to thromboxane A2 or prostacyclin differed in coronary arteries from male compared with female pigs. Activity for calcium-dependent or -independent NO synthase was similar in both sexes. These results suggest that normal fluctuations in endogenous sex steroid hormones do not affect endothelium-dependent relaxations in coronary arteries from female pigs. There are, however, gender differences in endothelium-dependent relaxations that are indomethacin sensitive and may be due to cyclooxygenase products other than thromboxane A2 or prostacyclin. PMID- 9374770 TI - Effect of long-term food restriction on cardiac mechanics. AB - Food restriction (FR) is the only known intervention capable of increasing mammalian life span. It not only increases longevity, but reduces the incidence of a broad spectrum of age-related pathologies, including cardiomyopathy, and retards the physiological decline associated with aging. Previous work from this laboratory has shown that long-term FR affects the contractile machinery of the heart, shifting the cardiac myosin profile from the fast, V1 isoform to the slow, V3 isoform. The aim of the present study was to determine whether FR also induces changes in cardiac mechanics. Isolated, isovolumically beating hearts were examined from four groups of rats: 1) ad libitum-fed rats killed at 10-13 mo of age, 2) FR rats offered only 60% of the calories consumed by ad libitum-fed rats and killed at the same age, 3) young ad libitum-fed rats having the same heart weights as the FR rats, and 4) ad libitum-fed rats subjected to short-term FR, i.e., for the last 3 wk of life, and also killed at 10-13 mo of age. Both short- and long-term FR profoundly and to approximately the same extent affected cardiac mechanics. Hearts from FR rats developed much higher pressures than hearts from the ad libitum-fed rats under conditions of low-calcium perfusate. This difference disappeared, however, when contractility was enhanced by either calcium or isoproterenol. FR prolonged both contraction and relaxation times. Long-term ad libitum-fed rats (adult, 10-13 mo of age) had a lower isoproterenol sensitivity than the young ad libitum-fed rats (10 wk of age). Both short- and long-term FR restored the sensitivity to isoproterenol. In summary, FR profoundly affects many aspects of cardiac mechanics, enhancing some age-related changes (prolongation of the contraction and relaxation times), attenuating another (increasing the isoproterenol sensitivity), and, finally, inducing some unique changes unrelated to age (increased pressure development under low-calcium perfusate). PMID- 9374771 TI - Energetics of heart muscle contraction under high K perfusion: verapamil and Ca effects. AB - Tension-dependent (TDH) and tension-independent heat (TIH) release were measured during single isovolumetric contractions in the arterially perfused rat ventricle. Under perfusion with 7 mM K-0.5 mM Ca, TDH showed only one component (H3), whereas TIH could be divided into two components (H1 and H2) of short evolution (similar to the classically identified activation heat) and one component (H4) of long duration (dependent on mitochondrial respiration). Under 25 mM K, TIH components (i.e., H1, H2, and H4) increased with the increase in extracellular Ca concentration ([Ca]o) from 0.5 to 4 mM, and H3 correlated with pressure at all [Ca]o, with regression parameters similar to those observed under 7 mM K. Under 25 mM K-2 mM Ca, peak pressure development (P), H1, H2, and H3, plotted against the number of beats under 0.4 microM verapamil, exponentially decreased, but H4 decreased to 5.5 +/- 2.9% in the first contraction and remained constant thereafter. Under hypoxia, P, H1, H2, and H3 progressively decreased for about six contractions, but H4 was not detectable from the second contraction. The results suggest that increasing extracellular K concentration decreases contractile economy mainly by increasing energy expenditure related to a Ca dependent (verapamil-sensitive) mitochondrial activity that is not related to force generation. PMID- 9374772 TI - Dynamics of cardiovascular responses to repeated partial umbilical cord compression in late-gestation sheep fetus. AB - We characterized the detailed hemodynamics of fetal blood pressure, heart rate, common umbilical blood flow, and femoral blood flow responses to partial compression of the umbilical cord and tested the hypothesis that repeated cord compression modulates fetal cardiovascular responses in 10 chronically instrumented fetal sheep at approximately 130 days of gestation. In five fetuses (group I), partial compression of the umbilical cord was induced 12 times, each for 5 min at 15-min intervals. Each cord compression reduced common umbilical blood flow by 50% and produced modest falls in fetal pH (7.33 +/- 0 to 7.29 +/- 0) and arterial PO2 (21.1 +/- 0.2 to 16.8 +/- 0.2 mmHg) and a mild increase in arterial PCO2 (49.9 +/- 0.5 to 54.9 +/- 0.4 mmHg). Sham experiments were performed in five other fetuses (group II). Second-by-second analysis of group I fetal cardiovascular data revealed a clear biphasic response to partial cord compression. Phase I (1st min of cord compression) was characterized by a rapid bradycardia and a rapid femoral vasoconstriction (primary response); phase II (minutes 2-5 of cord compression) was characterized by a delayed bradycardia and a return of femoral vascular resistance toward baseline (secondary response). Repeated cord compression abolished the primary, but not the secondary, cardiovascular responses. These results demonstrate that fetal cardiovascular responses to stress may be modified by preexposure to repeated intrauterine challenges. PMID- 9374773 TI - Role of CD18-ICAM-1 in the entrapment of stimulated leukocytes in alveolar capillaries of perfused rat lungs. AB - This study aimed to examine the behavior of stimulated leukocytes in the pulmonary microcirculation. The leukocyte-endothelium interaction was visualized under physiological shear rates in perfused rat lungs using high-speed confocal laser video microscopy. Leukocytes labeled with carboxyfluorescein were stimulated with cytokine-induced neutrophil chemoattractant (CINC/gro), which caused L-selectin shedding and inverse upregulation of CD18. Neither unstimulated nor stimulated leukocytes exhibited rolling in either pulmonary arterioles or venules, whereas both were sequestered in capillaries. Approximately 50% of stimulated leukocytes showed a transient cessation of movement in pulmonary capillaries. The CINC/ gro stimulation, which inhibited leukocyte rolling and adhesion to mesenteric venules, reduced leukocyte velocity and increased leukocytes in pulmonary capillaries. Pretreatment with monoclonal antibodies against intercellular adhesion molecule-1 (ICAM-1) or CD18 attenuated these changes. Confocal microfluorography revealed constitutive expression of ICAM-1 not only in venules but also abundantly in capillary networks. These results suggest that selectin-independent, CD18-ICAM-1-dependent capillary sequestration is one of the major mechanisms by which activated leukocytes accumulate in the lungs. PMID- 9374774 TI - Clearance receptors and endopeptidase: equal role in natriuretic peptide metabolism in heart failure. AB - The effects of separate and combined endopeptidase inhibition (by SCH-32615) and natriuretic peptide receptor C blockade [by C-ANP-(4-23)] on the clearance and bioactivity of atrial (ANP) and brain (BNP) natriuretic peptides was investigated in eight sheep with heart failure. SCH-32615 and C-ANP-(4-23) administered separately induced significant and proportionate dose-dependent rises in plasma ANP, BNP, and guanosine 3',5'-cyclic monophosphate (cGMP) levels. Associated with these changes were reductions in arterial pressure, left atrial pressure, and peripheral resistance and increases in cardiac output, urine volume, sodium excretion, and creatinine clearance. SCH-32615 induced greater diuresis and natriuresis than C-ANP-(4-23). Combined administration of SCH-32615 and C-ANP-(4 23) induced greater than additive rises in plasma ANP, BNP, and cGMP concentrations, with enhanced hemodynamic effects, diuresis, and natriuresis and reduced plasma aldosterone levels. In conclusion, we find that the enzymatic and receptor clearance pathways contribute equally to the metabolism of endogenous ANP and BNP in sheep with heart failure. Combined inhibition of both degradative pathways was associated with enhanced hormonal, hemodynamic, and renal effects and may have greater potential therapeutic value than either agent separately. PMID- 9374775 TI - A novel phospholipase C- and cAMP-independent positive inotropic mechanism via a P2 purinoceptor. AB - Although ATP, acting through a P2 purinoceptor, can stimulate a pronounced positive inotropic effect in cardiac ventricular myocytes, the receptor-effector mechanism that underlies this stimulatory cardiac action is not well understood. The objectives of the present study were to develop the cultured chick embryo ventricular myocytes as a novel model for the cardiac P2 purinoceptor and to determine the mechanism underlying its positive inotropic effect. ATP caused an 89 +/- 8.9% (n = 14 cells) increase in the myocyte contractility, with an efficacy and potency order of ATP > ADP > AMP >> adenosine. 2-Methylthio-ATP (2 MeS-ATP) but not alpha,beta-methylene-ATP was able to stimulate myocyte contractility, with a maximal increase of 54 +/- 2.6% (n = 11 cells). Although UTP potently stimulates phosphoinositide hydrolysis, it had an only modest positive inotropic effect (27 +/- 7% maximal increase; n = 8 cells). In contrast to previous suggestions, the 2-MeS-ATP-stimulated positive inotropic response does not require the action of phospholipase C (PLC), such as that of the inositol phosphates; the UTP effect on contractility appears to be mediated via the 2-MeS-ATP-sensitive P2 receptor. The PLC inhibitor U-73122 had no effect on the 2-MeS-ATP-stimulated increase in contractility, providing further evidence against a role for PLC in the inotropic effect of 2-MeS-ATP. An adenosine 3',5' cyclic monophosphate-independent Ca2+ entry-stimulating mechanism appears to underlie a direct coupling of the receptor to stimulation of the myocyte contractility. This new PLC- and adenosine 3',5'-cyclic monophosphate-independent positive inotropic mechanism represents a target for developing novel positive inotropic therapeutics. PMID- 9374776 TI - Contributions of acetylcholine and nitric oxide to forearm blood flow at exercise onset and recovery. AB - The contributions of acetylcholine and/or nitric oxide (NO) to the rapid changes in human forearm blood flow (FBF) at the onset and recovery from mild exercise were studied in eight subjects. Rhythmic handgrip contractions were performed during brachial artery infusions of saline (2 ml/min; control), atropine (0.2 mg over 3 min), to block acetylcholine binding to muscarinic receptors, or atropine + NG-monomethyl-L-arginine (L-NMMA; 4 mg/min for 4 min), to additionally inhibit NO synthase. Brachial artery mean blood velocity (MBV; pulsed Doppler ultrasound) and diameter (echo Doppler) were measured continuously, and FBF was calculated. Atropine reduced acetylcholine-induced increases in FBF by approximately 71% (P < 0.05). FBF at rest was reduced by atropine and further reduced with atropine + L NMMA. Both drug conditions reduced FBF during exercise by approximately 10% compared with control, with no difference between drug treatments. Brachial artery diameter was unchanged from rest by exercise, recovery, and drug treatments. Neither drug treatment altered the rate or magnitude of the increase in FBF above rest. Peak FBF after exercise was reduced by atropine and atropine + L-NMMA. Total FBF during 5 min of recovery was reduced with atropine + L-NMMA compared with control and atropine. The results suggest that 1) acetylcholine and NO mechanisms additively contribute to FBF levels at rest, 2) a cholinergic mechanism adjusts the absolute FBF levels during exercise, 3) neither acetylcholine nor NO is essential to observe the normal time course or magnitude of the exercise response, and 4) NO contributes to the FBF response during recovery from exercise. PMID- 9374777 TI - Role of cadherins and plakoglobin in interendothelial adhesion under resting conditions and shear stress. AB - The role of cadherins and the cadherin-binding cytosolic protein plakoglobin in intercellular adhesion was studied in cultured human umbilical venous endothelial cells exposed to fluid shear stress. Extracellular Ca2+ depletion (< 10(-7) M) caused the disappearance of both cadherins and plakoglobin from junctions, whereas the distribution of platelet endothelial cell adhesion molecule 1 (PECAM 1) remained unchanged. Cells stayed fully attached to each other for several hours in low Ca2+ but began to dissociate under flow conditions. At the time of recalcification, vascular endothelial (VE) cadherin and beta-catenin became first visible at junctions, followed by plakoglobin with a delay of approximately 20 min. Full fluid shear stress stability of the junctions correlated with the time course of the reappearance of plakoglobin. Inhibition of plakoglobin expression by microinjection of antisense oligonucleotides did not interfere with the junctional association of VE-cadherin, PECAM-1, and beta-catenin. The plakoglobin deficient cells remained fully attached to each other under resting conditions but began to dissociate in response to flow. Shear stress-induced junctional dissociation was also observed in cultures of plakoglobin-depleted arterial endothelial cells of the porcine pulmonary trunk. These observations show that interendothelial adhesion under hydrodynamic but not resting conditions requires the junctional location of cadherins associated with plakoglobin. beta-Catenin cannot functionally compensate for the junctional loss of plakoglobin, and PECAM 1-mediated adhesion is not sufficient for monolayer integrity under flow. PMID- 9374779 TI - Protein kinase A does not alter unloaded velocity of sarcomere shortening in skinned rat cardiac trabeculae. AB - Whether beta-adrenergic stimulation affects the cross-bridge cycling rate independently of its effect on Ca2+ handling by the cardiac myocyte is still unknown. An increase in cross-bridge cycling rate may result in increased unloaded velocity of sarcomere shortening (V0). To test this hypothesis directly, skinned rat cardiac trabeculae were attached between a silicon strain gauge (approximately 3.5 kHz resonant frequency) and a fast displacement motor. V0 was measured by a modified "Edman slack test" during a single maximal activation using seven to eight sarcomere-length step releases (measured by laser diffraction) ranging between 0.12 and 0.20 micron (15.0 +/- 0.1 degrees C). beta Adrenergic stimulation was mimicked by exposing the trabeculae to the catalytic subunit of protein kinase A (PKA). Treatment with PKA (3 micrograms/ml; 45 min) caused a significant (P < 0.01) increase (41 +/- 13%) in the Ca2+ concentration required for half-maximal steady-state tension development. Neither maximum tension nor V0 was affected by treatment with PKA, suggesting that beta adrenergic stimulation does not affect the rate-limiting step of cross-bridge cycling during unloaded shortening in myocardium. PMID- 9374778 TI - Effect of endogenous natriuretic peptide system on ventricular and coronary function in failing heart. AB - Ventricular concentrations of atrial, brain (BNP) and C-type natriuretic peptide are enhanced in congestive heart failure (CHF). Natriuretic peptide receptors are present on ventricular myocytes and stimulate guanosine 3',5'-cyclic monophosphate (cGMP) production. cGMP has been demonstrated to affect myocyte function in vitro. Thus we hypothesized that the intracardiac natriuretic peptide system may modulate myocardial and coronary function in CHF. To test this hypothesis, the effects of an intracoronary infusion of the natriuretic peptide receptor antagonist HS-142-1 on ventricular and coronary function were examined in anesthetized dogs with chronic CHF. To determine whether receptor stimulation had contrasting effects to those of receptor blockade, intracoronary BNP was infused in anesthetized normal and CHF dogs. Low-dose HS-142-1 delayed and slowed left ventricular (LV) relaxation and decreased coronary blood flow without changes in LV pressures. Higher doses further impaired LV relaxation without further decreases in coronary blood flow. In normal and CHF dogs, exogenous BNP produced the opposite effect with a quicker onset and faster rate of LV relaxation without effects on LV pressures or coronary blood flow. The endogenous natriuretic peptide system has an autocrine-paracrine role to modulate LV and coronary vascular function in CHF. PMID- 9374780 TI - Flow-induced dilation of rat soleus feed arteries. AB - Flow-induced dilation is thought to contribute to dilation of skeletal muscle arteries and arterioles during exercise hyperemia. We sought to determine whether rat soleus feed arteries (SFA) exhibit flow-induced dilation and to evaluate the potential contribution of flow-induced dilation of SFA to exercise hyperemia. Rat SFA were isolated and cannulated to allow pressure and intraluminal flow to be independently controlled. Intraluminal pressure was maintained at 90 cmH2O throughout the experiment. All SFA (n = 13) developed spontaneous tone and dilated in response to flow. Flow of 10 and 14 microliters/min produced a 34 +/- 14 and 56 +/- 17 microns increase above basal diameter (135 +/- 12 microns), respectively. Flows > 14 microliters/min produced little further dilation. Maximum flow-induced dilation was 86 +/- 3% of passive diameter determined in calcium-free physiological saline solution. Calculated shear stress was maintained at 4-6 dyn/cm2 at flows of 10-20 microliters/min but increased at greater flows because SFA did not dilate further. To determine whether dilation in response to flows in this range may contribute to exercise hyperemia, we estimated in vivo SFA blood flows from previously published soleus blood flow data. Anesthetized rats are estimated to have flows of 10 microliters/min per SFA, and conscious rats are estimated to have flows of 95 (nonexercising), 153 (walking), and 225 (running) microliters/min per SFA. Corresponding shear stresses were estimated to be 26 (anesthetized), 47 (conscious, nonexercising), 75 (walking), and 111 (running) dyn/cm2. Because estimated in vivo values for both flow and wall shear stress are far greater than the flow and/or shear stresses at which maximal flow-induced dilation occurs in vitro, we conclude that flow-induced dilation contributes little to dilation of SFA during locomotory exercise. PMID- 9374781 TI - The Frank-Starling mechanism is not mediated by changes in rate of cross-bridge detachment. AB - We tested the hypothesis that the Frank-Starling relationship is mediated by changes in the rate of cross-bridge detachment in cardiac muscle. We simultaneously measured isometric force development and the rate of ATP consumption at various levels of Ca2+ activation in skinned rat cardiac trabecular muscles at three sarcomere lengths (2.0, 2.1, and 2.2 microns). The maximum rate of ATP consumption was 1.5 nmol.s-1.microliter fiber vol-1, which represents an estimated adenosinetriphosphatase (ATPase) rate of approximately 10 s-1 per myosin head at 24 degrees C. The rate of ATP consumption was tightly and linearly coupled to the level of isometric force development, and changes in sarcomere length had no effect on the slope of the force-ATPase relationships. The average slope of the force-ATPase relationships was 15.5 pmol.mN-1.mm-1. These results suggest that the mechanisms that underlie the Frank-Starling relationship in cardiac muscle do not involve changes in the kinetics of the apparent detachment step in the cross-bridge cycle. PMID- 9374782 TI - Muscle cooling delays activation of the muscle metaboreflex in humans. AB - Elevation of muscle temperature has been shown to increase muscle sympathetic nerve activity (MSNA) during isometric exercise in humans. The purpose of the present study was to evaluate the effect of muscle cooling on MSNA responses during exercise. Eight subjects performed ischemic isometric handgrip at 30% of maximal voluntary contraction to fatigue followed by 2 min of postexercise muscle ischemia (PEMI), with and without local cooling of the forearm. Local cooling of the forearm decreased forearm muscle temperature from 31.8 +/- 0.4 to 23.1 +/- 0.8 degrees C (P = 0.001). Time to fatigue was not different during the control and cold trials (156 +/- 11 and 154 +/- 5 s, respectively). Arterial pressures and heart rate were not significantly affected by muscle cooling during exercise, although heart rate tended to be higher during the second minute of exercise (P = 0.053) during muscle cooling. Exercise-induced increases in MSNA were delayed during handgrip with local cooling compared with control. However, MSNA responses at fatigue and PEMI were not different between the two conditions. These findings suggest that muscle cooling delayed the activation of the muscle metaboreflex during ischemic isometric exercise but did not prevent its full expression during fatiguing contraction. These results support the concept that muscle temperature can play a role in the regulation of MSNA during exercise. PMID- 9374783 TI - Interaction of PKC and NOS in signal transduction of microvascular hyperpermeability. AB - Our previous studies have shown that inflammatory mediators increase microvascular permeability through a phospholipase C-nitric oxide synthase (NOS) guanylate cyclase cascade. The aim of this study is to delineate in more detail the signaling pathway leading to microvascular hyperpermeability. Endothelial cytosolic calcium and the apparent permeability coefficient of albumin (Pa) were measured in isolated and perfused coronary venules. Histamine stimulated a rapid increase in cytosolic calcium followed by a transient elevation in Pa. The NOS inhibitor NG-monomethyl-L-arginine (L-NMMA) and the guanosine 3',5'-cyclic monophosphate-dependent protein kinase G (PKG) inhibitor KT-5823 abolished the hyperpermeability but did not affect the calcium response to histamine. Similarly, the calcium ionophore ionomycin produced a calcium spike preceding venular hyperpermeability. Blockage of the NOS-PKG cascade inhibited the increase in Pa, whereas the endothelial calcium was still elevated on administration of ionomycin. Furthermore, the relationship between protein kinase C (PKC) and the calcium-NOS-PKG pathway in modulation of venular permeability was investigated. Stimulation of PKC with phorbol 12-myristate 13-acetate (PMA) dramatically increased basal Pa without significantly changing the cytosolic calcium level. The selective PKC inhibitor bisindolylmaleimide abolished the effect of PMA but did not alter the effect of histamines on Pa. In contrast, both L-NMMA and KT 5823 were able to greatly attenuate the increase in Pa caused by PMA. These results suggest that 1) elevation of endothelial cytosolic calcium is an early signaling event preceding nitric oxide (NO) synthesis in the transduction of endothelial hyperpermeability, and 2) activation of PKC may alter the endothelial barrier function partially through the modulation of NO production. PMID- 9374784 TI - Myocardial, skeletal muscle, and renal blood flow during exercise in conscious dogs with heart failure. AB - The present study characterizes the hemodynamic and neurohumoral responses to moderate treadmill exercise in conscious dogs with pacing-induced heart failure. Seven dogs were instrumented with a left ventricular micromanometer, ultrasonic crystals for the measurement of systolic wall thickening, left atrial and aortic catheters for the injection of colored microspheres and reference withdrawal, respectively, and ventricular pacing leads with a subcutaneous pacemaker. Dogs were run on a treadmill at a speed of 5 km/h. After control studies, heart failure was induced by rapid left ventricular pacing at 250 beats/min for (mean +/- SD) 23 +/- 6 days. In the control state, cardiac output was increased from 4.5 +/- 1.5 to 7.9 +/- 1.4 l/min (P < 0.05 vs. rest). With heart failure, cardiac output was decreased to 2.5 +/- 0.5 l/min at rest (P < 0.05 vs. control state) and was only 3.0 +/- 0.3 l/min during exercise (P < 0.05 vs. control state; not significant vs. rest). Myocardial and, more so, skeletal muscle blood flows at rest were reduced in heart failure; their increases with exercise were attenuated. An increase in renal blood flow during exercise in the control state was no longer seen in heart failure. Increases in plasma catecholamines and lactate during exercise were more pronounced in heart failure. In conclusion, in heart failure, the increase in cardiac output during exercise was largely attenuated. Increased catecholamine levels may have contributed to splanchnic vasoconstriction and preferential distribution of cardiac output into the working skeletal muscle. PMID- 9374786 TI - Electrical properties of iridial arterioles of the rat. AB - When intracellular recordings were made from iridial arterioles, the cells had membrane potentials of about -65 mV and perivascular nerve stimulation evoked a membrane depolarization. When these cells were labeled with lucifer yellow, all cells that responded to perivascular nerve stimulation had the morphological characteristics of smooth muscle cells. Cells with the morphological characteristics of endothelial cells were never stained. When impaled with two separate recording electrodes, the smooth muscle layer was shown to form an electrical syncytium with a membrane time constant of approximately 80 ms and an electrical length constant of approximately 900 microns. At the ultrastructural level, areas of close apposition were frequently observed between adjacent smooth muscle cells and between adjacent endothelial cells. On the other hand, at contacts between smooth muscle and endothelial cells, the membranes characteristically had much larger separations. The observations show that individual smooth muscle cells are electrically coupled to their neighbors, but the morphological studies raise the possibility that in these arterioles the endothelial and muscle layers are electrically separate. PMID- 9374785 TI - ATP-sensitive potassium channel mediates delayed ischemic protection by heat stress in rabbit heart. AB - Heat shock protects against myocardial ischemia-reperfusion injury possibly via increased expression of heat shock proteins. The direct evidence of heat shock protein protection in vivo remains circumstantial, and no other new mechanism of protection has been proposed. Recent studies suggest that opening of ATP sensitive K+ channels (KATP channels) plays an important role in ischemic preconditioning; however, it is not known whether this channel is also important in delayed protection conferred by heat shock. Anesthetized rabbits underwent heat shock treatment by raising core temperature to 42 degrees C for 15 min. Twenty-four hours later, the animals were reanesthetized and subjected to regional ischemia-reperfusion. The specific KATP channel blockers glibenclamide (0.3 mg/kg i.p.) and sodium 5-hydroxydecanoate (5HD; 5 mg/kg i.v.) were used to block the channel function. The drugs were administered at two different times, either pre-heat stress or preischemia. Infarct size was determined by triphenyltetrazolium chloride staining. The 72-kDa heat shock protein (HSP 72) was measured by Western blots. Our results show that heat shock produced a marked reduction in infarct size (39.4 +/- 8.1 to 14.3 +/- 2.5% of risk area, P < 0.05). Glibenclamide and 5HD completely abolished heat shock-induced reduction in infarct size (42.3 +/- 0.32 and 33.7 +/- 4.8%) when given before ischemia reperfusion; however, these antagonists failed to block protection when administered before the onset of heat shock. Furthermore, the enhanced expression of HSP 72 in heat shock groups was not diminished by glibenclamide or 5HD, suggesting a lack of a direct role of this protein in conferring cardiac protection by heat shock. The complete blockade of cardiac protection by glibenclamide and 5HD strongly suggests that opening of this channel is a very important component of heat shock-induced ischemic protection in rabbit hearts. PMID- 9374787 TI - Fatty acid uptake is preserved in chronically dysfunctional but viable myocardium. AB - Glucose uptake appears preserved or even enhanced in the chronically dysfunctional but viable myocardium. However, the use of other fuels such as free fatty acids (FFA) remains unknown. We studied FFA uptake in the chronically dysfunctional but viable myocardium in seven patients with an occluded major coronary artery and a corresponding chronic wall motion abnormality but no previous infarction. Myocardial FFA uptake kinetics in the fasting state were measured with positron emission tomography (PET) and 14(R,S)-[18F]fluoro-6-thia heptadecanoic acid ([18F]FTHA). The FFA uptake index was calculated by multiplying the fractional [18F]FTHA uptake with serum FFA concentration. Myocardial blood flow (MBF) was measured with [15O]H2O and PET. Myocardial viability was confirmed with a static 18F-labeled 2-fluoro-2-deoxy-D-glucose PET imaging and a follow-up echocardiography in the revascularized patients. Regional MBF was slightly but not significantly lower in the dysfunctional compared with normal myocardial segments (0.76 +/- 0.18 vs. 0.81 +/- 0.14 ml.min-1.g-1, means +/- SD; P = 0.16). The fractional [18F]FTHA uptake rates [0.11 +/- 0.03 vs. 0.11 +/- 0.04 ml.g-1.min-1; not significant (NS)], and the FFA uptake indexes (5.8 +/- 1.7 vs. 5.8 +/- 2.1 mumol.100g-1.min-1; NS) were similar in the dysfunctional but viable and in the normal myocardial regions. Thus, in the chronically dysfunctional but viable (collateral-dependent) myocardium, the fatty acid uptake probed by [18F]FTHA appears preserved. Taken together with preserved glucose uptake, the results indicate that there is uncoupling of substrate uptake and mechanical function in the chronically dysfunctional but viable myocardium. PMID- 9374788 TI - Ionic basis of ryanodine's negative chronotropic effect on pacemaker cells isolated from the sinoatrial node. AB - Spontaneous electrical activity and indo 1 fluorescence ratios were recorded simultaneously in cultured pacemaker cells isolated from the rabbit sinoatrial node. Ryanodine (10 microM) reduced the amplitude of action potential-induced intracellular Ca2+ (Ca2+i) transients by 19 +/- 3%, increased the time constant for their decay by 51 +/- 5%, and slowed spontaneous firing by 32 +/- 3%. 1,2 Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA)-acetoxymethyl ester (AM; 25 microM) inhibited the Ca2+i transients and slowed spontaneous firing by 28 +/- 4%. Ryanodine did not alter hyperpolarization-activated or time independent inward current, but it reduced the sum of L- and T-type Ca2+ currents (ICa,L and ICa,T) in both the presence and absence of BAPTA-AM. In contrast, ICa,L was unchanged by ryanodine. Slow inward current tails, presumed to be Na/Ca exchange current (INa/Ca), were abolished by BAPTA or ryanodine. The results suggest that a decrement of ICa,T, due to reduction of the intracellular Ca2+ concentration or a direct effect of ryanodine on T-type Ca2+ channels, contributes to the negative chronotropic effect. Another possibility, based primarily on theory and results in other preparations, is that a reduction of INa/Ca, as a consequence of the smaller action potential-induced Ca2+i transients, contributes to the effect of ryanodine. PMID- 9374789 TI - Role of nitric oxide in poly(I-C)-induced endothelial cell expression of leukocyte adhesion molecules. AB - Polyinosinic-polycytidylic acid [poly(I-C)] is a synthetic double-stranded RNA (dsRNA) that simulates a viral-infected state in cells. It has been shown that viral infection, as well as poly(I-C), stimulates leukocyte adhesion to endothelial cell (EC) monolayers and that this is mediated through the surface expression of the adhesion molecules E-selectin, vascular cell adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule 1. We have tested the involvement of nitric oxide (NO) in poly(I-C)-induced monocytic cell adhesion to human vascular EC. Using primary cultured EC for these studies, we confirmed the results from previous reports that these cells have higher basal levels of NO production than passaged cells. Poly(I-C)-induced monocytic cell adhesion to primary EC was concentration-dependently inhibited by 40-74% by the nitric oxide synthase (NOS) inhibitor NG-methyl-L-arginine (L-NMA), as well as three other NOS inhibitors, without significantly affecting interleukin-1 beta-induced adhesion. L-NMA inhibited poly(I-C)-induced surface expression of E-selectin and VCAM-1 by 25 and 45%, respectively, and mRNA levels of E-selectin and VCAM-1 by 62 and 74%, respectively. Primary EC transiently transfected with a plasmid containing an E selectin promoter-driven luciferase reporter gene showed that L-NMA treatment reduced poly(I-C)-induced E-selectin promoter activity to basal levels. Electrophoretic mobility shift analysis indicated that poly(I-C)-induced nuclear factor-kappa B (NF-kappa B) binding to a radiolabeled oligonucleotide corresponding to the consensus NF-kappa B binding domain of the E-selectin promoter was decreased by L-NMA pretreatment. Hence, NO appears to augment E selectin gene expression in response to poly(I-C) at the transcriptional level in vascular EC. Collectively, these data support the hypothesis that NO augments poly(I-C)-induced EC activation. These data suggest a novel role for NO as a response mediator in dsRNA-induced leukocyte adhesion to EC. PMID- 9374790 TI - Sarcoplasmic reticulum function in determining atrioventricular contractile differences in rat heart. AB - The relationships between the contractile characteristics and the sarcoplasmic reticulum (SR) function of rat atrial and ventricular trabeculae were compared. The isometric developed tension (DT) and the rates of contraction (+ dT/dt) and relaxation (-dT/dt) normalized to cross-sectional area were 3.7, 2.2, and 1.8 times lower, respectively, in intact atrial strips compared with ventricular strips, whereas + dT/dt and -dT/dt (normalized to DT) were 2.3 and 2.8 times higher, respectively, in atria. Atria exhibited a maximal potentiation of DT after shorter rest periods than ventricles and a lower reversal for prolonged rest periods. Caffeine-induced tension transients in saponin-permeabilized fibers suggested that the Ca2+ concentration released in atrial myofibrils reached a lower maximum and decayed more slowly than in ventricular preparations. However, the tension-time integrals indicated an equivalent capacity of sequestrable Ca2+ in SR from both tissues. In atrial, as in ventricular myocardium, the SR Ca2+ uptake was more efficiently supported by ATP produced by the SR-bound MM form of creatine kinase (CK; MM-CK) than by externally added ATP, suggesting a tight functional coupling between the SR Ca2+ adenosinetriphosphatase (ATPase) and MM CK. The maximal rate of oxalate-supported Ca2+ uptake was two times higher in atrial than in ventricular tissue homogenates. The SR Ca(2+)-ATPase 2a mRNA content normalized to 18S RNA was 38% higher in atria than in ventricles, whereas the amount of mRNA encoding the alpha-myosin heavy chain, calsequestrin, and the ryanodine receptor was similar in both tissues. Thus a lower amount of readily releasable Ca2+ together with a faster uptake rate may partly account for the shorter time course and lower tension development in intact atrial myocardium compared with ventricular myocardium. PMID- 9374791 TI - Coronary constriction impairs cardiac function and induces myocardial damage and ventricular remodeling in mice. AB - To establish whether coronary artery narrowing (CAN) in mice was accompanied by depressed ventricular function, tissue injury, and modifications in cardiac anatomy, the left coronary artery was constricted in FVB/N mice and the animals were killed 7 days later. CAN consisted of a 53% reduction in luminal diameter, which resulted in a twofold increase in left ventricular end-diastolic pressure. Left ventricular systolic pressure and left ventricular + and -dP/dt decreased 15, 21, and 11%, respectively. Left ventricular weight-to-body weight ratio increased 33%. This hypertrophic adaptation was characterized by a 9 and 20% increase in the longitudinal and transverse cavitary diameters, which provoked a 1.5-fold expansion in chamber volume. In contrast, wall thickness decreased 15%. These anatomic and functional changes induced a threefold elevation in diastolic stress. Foci of reparative fibrosis were found in the endomyocardium and epimyocardium, involving 2-3% of the tissue. Finally, myocyte loss in the ventricle was 15%, and myocyte hypertrophy was 38%. Impaired ventricular function, diastolic Laplace overloading, myocyte loss, and decompensated eccentric hypertrophy in mice after CAN mimic the ischemic cardiomyopathic heart in humans. PMID- 9374792 TI - Measurement of cardiac output in small laboratory animals using recordings of blood conductivity. AB - No method exists which enables easy, frequent, and, at the same time, reliable cardiac output (CO) measurements in mice. To validate a simple indicator-dilution method suitable for frequent measurements of CO in small laboratory animals, a 5% glucose solution was injected as a bolus into femoral veins of mice and rats. The corresponding blood conductivity was measured continuously between an intra aortic and a rectal electrode. The resulting conductivity-dilution curves were used to calculate CO in mice during hypervolemia and hypovolemia and in conscious as well as halothane-anesthetized mice and rats. In rats, conductivity-dilution curves and time courses of plasma glucose concentration were recorded simultaneously. Compared with CO in awake animals, CO in both species was slightly, but not significantly, reduced during halothane anesthesia. CO was significantly and gradually reduced in hypovolemic mice (up to 58 ml blood/kg body wt), whereas hypervolemia (23 ml saline/kg body wt) had no significant effect. Simultaneous recordings of conductivity-dilution curves and time courses of plasma glucose concentration yielded corresponding values of CO (P < 0.001). Measurement of blood conductivity appears to be a reliable, simple, and convenient method for quantification of CO in small animals. PMID- 9374793 TI - Invasive hemodynamics and force-frequency relationships in open- versus closed chest mice. AB - We compared hemodynamics, ventricular function, and force-frequency relationships in six open-chest and six closed-chest anesthetized mice (FVB/N strain). Left ventricular (LV) pressure was measured with a 1.8- or 1.4-Fr Millar catheter placed via the right carotid artery and the LV apex in the closed- and open-chest state, respectively. Pacing was performed with electrodes placed either directly on atrial appendages (open chest) or with a 1-Fr bipolar catheter via the jugular vein (closed chest). Closed-chest animals had greater spontaneous heart rate (267 +/- 106 vs. 147 +/- 27 beats/min), LV systolic (81 +/- 14 vs. 48 +/- 9 mmHg) and diastolic pressures (11.2 +/- 4.8 vs. 5.6 +/- 2.4 mmHg), and maximal rise (+ dP/dtmax: 6,208 +/- 2,519 vs. 3,682 +/- 671 mmHg/s) and fall in pressure development (-dP/dtmax: -6,094 +/- 2,386 vs. -3,001 +/- 399 mmHg/s). LV systolic pressure (98 +/- 18 vs. 52 +/- 11 mmHg), + dP/dtmax (9,240 +/- 2,459 vs. 5,777 +/ 2,473 mmHg/s), and -dP/dtmax (-8,375 +/- 2,551 vs. -3,753 +/- 1,170 mmHg/s) were significantly higher when animals were matched at a heart rate of 420 beats/min in closed-chest vs. open-chest animals. Biphasic force-frequency relationships were seen in all animals, but the critical heart rate was greater in the closed- than open-chest animals (432 +/- 42 vs. 318 +/- 42 beats/min). We conclude that 1) there are significant differences between invasive indexes of systolic and diastolic function between the closed- and open-chest preparations, 2) there is a biphasic force-frequency relationship in the anesthetized mouse, and 3) dP/dtmax can be used to assess the cardiovascular phenotype. PMID- 9374794 TI - Blockage of the HERG human cardiac K+ channel by the gastrointestinal prokinetic agent cisapride. AB - Cisapride, a gastrointestinal prokinetic agent, is known to cause long Q-T syndrome and ventricular arrhythmias. The cellular mechanism is not known. The human ether-a-go-go-related gene (HERG), which encodes the rapidly activating delayed rectifier K+ current and is important in cardiac repolarization, may serve as a target for the action of cisapride. We tested the hypothesis that cisapride blocks HERG. The whole cell patch-clamp recording technique was used to study HERG channels stably expressed heterologously in HEK293 cells. Under voltage-clamp conditions, cisapride block of HERG is dose dependent with a half maximal inhibitory concentration of 6.5 nM at 22 degrees C (n = 25 cells). Currents rapidly recovered with drug washout. The onset of block by cisapride required channel activation indicative of open or inactivated state blockage. Block of HERG with cisapride after channel activation was voltage dependent. At 20 mV, 10 nM cisapride reduced HERG tail-current amplitude by 5%, whereas, at + 20 mV, the tail-current amplitude was reduced by 45% (n = 4 cells). At -20 and + 20 mV, 100 nM cisapride reduced tail-current amplitude by 66 and 90%, respectively. We conclude that cisapride is a potent blocker of HERG channels expressed in HEK293 cells. This effect may account for the clinical occurrence of Q-T prolongation and ventricular arrhythmias observed with cisapride. PMID- 9374795 TI - The imidazoline receptor in control of blood pressure by clonidine and allied drugs. AB - Clonidine, moxonidine, and rilmenidine are centrally acting antihypertensive agents that lower arterial pressure by inhibiting the tonic activity of sympathoexcitatory neurons in the rostral ventrolateral medulla. Competing hypotheses have been put forward by different investigators to explain the sympathoinhibition evoked by "imidazoline drugs": either via central actions at alpha 2-adrenergic receptors or novel I1-imidazoline receptors. These different perspectives are presented in the accompanying reviews. PMID- 9374796 TI - The I1-imidazoline-binding site is a functional receptor mediating vasodepression via the ventral medulla. AB - I1-imidazoline-binding sites fulfill all essential criteria for identification as receptors, including specificity of binding, association with physiological functions, appropriate anatomic and cellular and subcellular localization, and specific cell signaling pathways. Moreover, binding affinities correlate with functional drug responses. The evidence linking I1 receptors to vasodepression includes expression in RVLM and consistent correlations between vasodepressor potency in humans and animals and I1 binding affinity. Some I1 agonists are antagonists at alpha 2-adrenergic receptors (alpha 2AR), and these elicit vasodepression in RVLM. Potent alpha 2-agonists with phenylethylamine or guanidine structures are inactive in RVLM, yet highly effective in nucleus of the solitary tract, a region with well-defined alpha 2-mediated vasodepressor responses. Selective I1 agonists are used clinically to lower blood pressure with minimal alpha 2-mediated sedation. Moreover, when microinjected into the RVLM only antagonists active at I1 receptors can block the vasodepressor action of either local or systemic imidazolines. RVLM alpha 2-blockade has no effect. Some reports appear to conflict with the I1 receptor hypothesis; but these reports often make incorrect assumptions regarding drug specificity, overlook systemic effects of alpha 2-antagonists, or inappropriately analyze data. Blockade of gamma-aminobutyric acid (GABA) receptors blocks the vasodepressor action of imidazolines, implying a multisynaptic pathway. Thus imidazolines act via I1 receptors in RVLM to lower blood pressure, although alpha 2AR are also important, especially in NTS. PMID- 9374797 TI - Is the hypotensive effect of clonidine and related drugs due to imidazoline binding sites? AB - Clonidine and related alpha 2-adrenergic receptor (alpha 2AR) agonists lower arterial pressure primarily by an action within the central nervous system. These drugs also have varying degrees of affinity for other cellular components called nonadrenergic imidazoline binding sites (NAIBS). For over 20 years, the alpha 2AR agonist activity of clonidine-like drugs was thought to account for their therapeutic effects (alpha 2 theory). However, several groups have recently proposed a competing "imidazoline theory" according to which the hypotensive effect of clonidine-like drugs would in fact owe more to their affinity for one type of NAIBS, called I1 receptors. The alpha 2-theory is strongly supported by four main types of congruent data. First, the hypotensive effect of systemically administered clonidine is blocked by alpha 2AR antagonists that are without affinity for I1 NAIBs. Second, the hypotensive effect of intravenous clonidine is absent in genetically engineered mice in which a defective alpha 2AAR has been substituted for the normal one. Third, the sympatholytic effect of clonidine is consistent with the presence of conventional inhibitory alpha 2ARs on sympathetic preganglionic neurons and on their main excitatory inputs in the medulla oblongata. Fourth, the first I1 ligand without affinity for alpha 2ARs was found to be biologically inactive. The imidazoline theory is supported by a limited repertoire of whole animal "in vivo" pharmacological experiments that remain open to a wide range of interpretations. In conclusion, the bulk of the evidence strongly supports a largely predominant role of alpha 2AR mechanisms in the action of most clonidine-like agents at therapeutically relevant doses or concentrations. Even the small pharmacological differences between these agents cannot yet be linked with certainty to their relative affinity for I1 NAIBS. PMID- 9374798 TI - Ascorbic acid disposition kinetics in the plasma and tissues of calves. AB - Kinetic plasma disposition parameters and tissue distribution of ascorbic acid (AA) and dihydroascorbic acid (DHA) were determined in newborn calves. After a radiolabeled AA intravenous administration, the plasma clearance (Cl) was low (40.8 +/- 9.5 ml.kg-1.h-1), the steady-state volume of distribution (Vss) was very high (8.9 +/- 2.2 l/kg), and the AA mean residence time (MRT) was long (230 +/- 85 h). After administration of a 3-g dose of AA, the Cl was high (450 +/- 146 ml.kg-1.h-1), the Vss was low (0.658 +/- 0.236 l/kg), and the MRT was short (1.49 +/- 0.41 h), indicating a strong nonlinearity of AA disposition in calves and the impossibility of preventing scurvy with the use of a loading AA dose. Nonlinearity was explained by the saturation of both kidney reabsorption and tissue uptake. The estimated AA body pool size was 23.1 +/- 6.8 mg/kg. On the basis of a compartmental analysis and actual tissue concentration measurements, it is suggested that the lung (19% of the pool) constitutes a low-capacity but rapidly mobilized pool able to cover an acute need for AA, whereas muscle and liver (40 and 33% of the pool, respectively) are high-capacity AA pools, but slowly mobilized and involved in covering the calf's long-term AA requirements. The average daily AA entry rate over the first 7 days of life was 3.43 +/- 1.16 mg/kg, and it is suggested that the calf is able to synthesize AA at an early stage. PMID- 9374799 TI - Glycyl-L-glutamine [beta-endorphin-(30-31)] attenuates hemorrhagic hypotension in conscious rats. AB - The profound hypotension caused by acute hemorrhage is thought to involve opioid peptide neurons. In this study, we tested whether glycyl-L-glutamine [Gly-Gln; beta-endorphin-(30-31)], a nonopioid peptide derived from beta-endorphin processing, prevents the cardiovascular depression induced by hemorrhage in conscious and anesthetized rats. Previously, we found that Gly-Gln inhibits the hypotension and respiratory depression produced by beta-endorphin and morphine but does not affect opioid antinociception. Hemorrhage (2.5 ml/100 g body wt over 20 min) lowered arterial pressure in conscious rats (from 120.1 +/- 2.9 to 56.2 +/- 4.7 mmHg) but did not change heart rate significantly. Intracerebroventricular Gly-Gln (3, 10, or 30 nmol) pretreatment inhibited the fall in arterial pressure and increased heart rate significantly. The response was dose related and was sustained during the 35-min posthemorrhage interval. Pentobarbital sodium anesthesia potentiated the hemodynamic response to hemorrhage and attenuated the effect of Gly-Gln. Gly-Gln (10 or 100 nmol icv) did not influence arterial pressure or heart rate in normotensive rats. These data indicate that Gly-Gln is an effective antagonist of hemorrhagic hypotension. PMID- 9374800 TI - 5-CT or DOI augments TRH analog-induced gastric acid secretion at the dorsal vagal complex. AB - Serotonin (5-HT) interacts with thyrotropin-releasing hormone (TRH) at the dorsal vagal complex (DVC) to augment TRH-induced stimulation of gastric acid secretion. To investigate the 5-HT receptor family involved in the augmentation response, prototypical 5-HT receptor-selective agonists (146 pmol) were coinjected with the TRH analog RX-77368 (RX; 12 pmol) into the rat DVC in a 30-nl volume. The DVC coordinates were 0.2 mm anterior, 0.2 mm right, 0.6 mm ventral with respect to the calamus scriptorius. Coinjection of RX with the 5-HT agonists 5 carboxyamidotryptamine (5-CT) or (+/-)-1-(4-iodo-2,5-dimethoxyphenyl)-2 aminopropane hydrochloride (DOI; 5-HT2 agonist) produced a 183 or 103% increase in gastric acid output compared with the RX injection alone. In contrast, coinjection of 2-methyl-5-HT (5-HT3 agonist) with RX produced no effect on RX induced increase in gastric acid secretion. Moreover, coinjection of SC-53116 (5 HT4 agonist) decreased the gastric acid output by 45% compared with the RX response itself. Examination of the RX/5-HT agonist coinjection response in more rostral regions of the DVC using the same doses (5-CT/RX or DOI/RX) revealed that only 5-CT was effective in producing the augmented response to TRH analog. The results suggest that activation of 5-CT- or DOI-sensitive receptors augments, and of 5-HT4 receptors inhibits, the gastric acid response to TRH analog injected into the DVC. Thus the integrated response to several serotonin receptor subtypes may mediate changes to the TRH response induced by 5-HT at the DVC. PMID- 9374801 TI - Effect of restraint stress on food intake and body weight is determined by time of day. AB - Three experiments were conducted to investigate the effect of restraint stress applied at different times of the light-dark cycle on feeding behavior and body weight of rats. Sprague-Dawley rats were restrained for 3 h in restraining tubes either at the start or the end of the light cycle. There was a significant reduction in food intake on the day of restraint and no change in food intake during a 10-day recovery period in either experiment. Reductions of food intake on the day of restraint were about the same for both restrained groups compared with their controls. When stress was applied in the evening, eating was inhibited during the first 2 h after restraint, whereas in rats restrained in the morning, feeding was suppressed twice: during the 4 h after restraint and during the first 2 h of the dark cycle. Restraint induced a significant weight loss that was greater in the rats stressed in the morning. Neuropeptide Y (NPY) levels determined at the time of food suppression for both experiments (beginning of the dark cycle) revealed an elevation of NPY in the paraventricular nucleus of rats stressed in the morning compared with other groups, but no difference in hypothalamic NPY mRNA expression. Expression of uncoupling protein mRNA in brown adipose tissue and leptin mRNA in epididymal fat, measured at the start of the dark period, was not altered by stress. There was an elevation of dopamine turnover in the hypothalami of rats restrained at the end of light cycle, but not those restrained in the morning. These results show that restraint stress has a greater effect on metabolism and energy balance when it is applied in the morning. Additional studies are needed to elucidate mechanisms involved in the suppression of food intake 9 h after restraint. PMID- 9374802 TI - Effects of severe hemorrhage on plasma ANP and glomerular ANP receptors. AB - Atrial natriuretic peptide (ANP) plays an important role in blood volume and electrolyte homeostasis in normovolemia and in hypervolemic states. The currently available information on the effects of hypovolemia on plasma ANP is contradictory. Moreover, possible regulation of ANP receptors during severe hemorrhagic hypovolemia has not been investigated. This study evaluated the effects of severe hemorrhage on plasma ANP and on the regulation of glomerular ANP receptor subtypes in anesthetized rats. Constant rate bleeding of 50% of total blood volume within 2 h induced a reproducible shock state characterized by marked decreases in blood pressure, heart rate, and hematocrit and an increase in plasma renin activity and aldosterone. Hemorrhaged rats exhibited a gradual significant increase in plasma ANP from 39.3 +/- 2.9 to 114.7 +/- 20.0 pmol/l 1 h after the bleeding (P < 0.001 from the initial value and P < 0.02 from the final value of sham-shock rats). Hemorrhage induced a significant decrease in total glomerular ANP binding sites (172 +/- 25 vs. 363 +/- 39 fmol/mg protein in hemorrhaged and sham-shock rats, respectively, P < 0.05). This decrease was mainly due to a significant decrease in ANPC receptors (132 +/- 22 vs. 312 +/- 40 fmol/mg protein in hemorrhaged and sham-shock rats, respectively, P < 0.05). Hemorrhage did not change glomerular ANPA receptor density. No significant differences in the affinity of the glomerular receptor subtypes for ANP were detected. Our data indicate that plasma ANP increases after prolonged severe hemorrhage. It is suggested that downregulation of renal ANPC receptors leads to reduced clearance of ANP and contributes to elevation of its plasma level after severe hemorrhage. PMID- 9374803 TI - Metabolic costs of mounting an antigen-stimulated immune response in adult and aged C57BL/6J mice. AB - Animals must balance their energy budget despite seasonal changes in both energy availability and physiological expenditures. Immunity, in addition to growth, thermoregulation, and cellular maintenance, requires substantial energy to maintain function, although few studies have directly tested the energetic cost of immunity. The present study assessed the metabolic costs of an antibody response. Adult and aged male C5BL/6J mice were implanted with either empty Silastic capsules or capsules filled with melatonin and injected with either saline or keyhole limpet hemocyanin (KLH). O2 consumption was monitored periodically throughout antibody production using indirect calorimetry. KLH injected mice mounted significant immunoglobulin G (IgG) responses and consumed more O2 compared with animals injected with saline. Melatonin treatment increased O2 consumption in mice injected with saline but suppressed the increased metabolic rate associated with an immune response in KLH-injected animals. Melatonin had no effect on immune response to KLH. Adult and aged mice did not differ in antibody response or metabolic activity. Aged mice appear unable to maintain sufficient heat production despite comparable O2 production to adult mice. These results suggest that mounting an immune response requires significant energy and therefore requires using resources that could otherwise be allocated to other physiological processes. Energetic trade-offs are likely when energy demands are high (e.g., during winter, pregnancy, or lactation). Melatonin appears to play an adaptive role in coordinating reproductive, immunologic, and energetic processes. PMID- 9374804 TI - Hormonal control of thermogenesis in perfused muscle of Muscovy ducklings. AB - Endocrine stimulation of muscle nonshivering thermogenesis (NST) in ducklings was investigated in vitro using a perfused hindlimb preparation maintained at 25 degrees C. Effects of flow rate, norepinephrine (NE), epinephrine, and glucagon on perfused muscle oxygen consumption (MO2) and perfusion pressure were studied. Control ducklings (Cairina moschata, 5 wk old) reared at thermoneutrality (25 degrees C, TN) were compared with two age-matched groups exhibiting muscle NST in vivo: cold-acclimated ducklings (4 degrees C, 4 wk, CA) and glucagon-treated ducklings (103 nmol/kg twice-daily, intraperitoneally, GT). Basal MO2 was higher in CA than in TN or GT ducklings and increased in all groups with elevated flow rates. Catecholamines increased both MO2 and perfusion pressure. The maximal effect on MO2 was higher in CA (+ 36%) and GT ducklings (+ 43%) than in controls (+ 31%), but was associated with reduced vasoconstriction. Flow rate did not consistently potentiate the NE response. At high doses, catecholamines became inhibitory on MO2 while a monotonous increase of pressure was still observed. Glucagon, by contrast, slightly decreased both MO2 and pressure. This vasodilatory effect was greater in CA ducklings than controls in preconstricted preparations. In vivo, low-dose epinephrine induced a modest thermogenic effect (+ 10%) in CA ducklings. These findings showed that duckling muscle thermogenesis is directly stimulated in vitro by catecholamines but not by glucagon. Higher in vitro thermogenic effects of NE in ducklings that were expected to exhibit muscle NST in vivo suggests catecholamine involvement in muscle NST in vivo. Potential vascular control of avian muscle NST is discussed. PMID- 9374805 TI - Development of independent ingestive responding to blockade of fatty acid oxidation in rats. AB - The present studies examined the development of ingestive responsiveness to blockade of fatty acid oxidation in rat pups using 2-mercaptoacetate (MA), an inhibitor of mitochondrial acyl-coenzyme A dehydrogenases, or methyl palmoxirate (MP), an inhibitor of carnitine palmitoyltransferase I (CPT-I). Rat pups aged 6, 9, 12, or 15 days of age received an intraperitoneal injection of 0, 100, 200, 400, or 800 mumol/kg MA, and intake of a commercial half-and-half or 15% glucose diet from the floor of test containers was assessed in a 30-min test beginning 1 h after administration of MA. The results demonstrate that, although no dose of MA affected intake of either diet in pups 9 days or younger, low doses of MA increased intake and the highest dose suppressed intake of both diets in pups 12 days of age or older. Physiological measurements indicated that levels of beta hydroxybutyrate were significantly lower following doses of 400 or 800 mumol/kg MA in 9-, 12-, and 15-day-old pups and that gastric emptying was inhibited in 12 and 15 day olds by 800 mumol/kg MA. Intake of a commercial half-and-half diet from the floor of test containers was also assessed in 12- to 18-day-old rat pups 6.5 h after they received a gavage load of 0, 1.25, 2.5, 5, or 10 mg/kg MP. Unlike MA, MP did not increase intake of a commercial half-and-half diet in rat pups 12 or 15-18 days of age; instead, the highest dose of MP suppressed intake in 15- to 18-day-old pups. The failure of MP to enhance intake in pups at the ages tested is likely related to composition of dam's milk; rat milk is high in medium-chain fatty acids that do not require CPT-I for entry into mitochondria. Thus it is likely that MP does not significantly block fatty acid oxidation in pups at the ages tested. On the other hand, blockade of fatty acid oxidation produced by MA significantly affects intake by 12 days of age, suggesting it may be the first metabolic signal that influences intake in rat pups. PMID- 9374806 TI - Influence of GABA in the nucleus of the solitary tract on blood pressure in baroreceptor-denervated rats. AB - We have previously reported that inhibition of the nucleus of the solitary tract (NTS) in chronically sinoaortic baroreceptor-denervated (SAD) rats has no effect on blood pressure in contrast to the marked increase in blood pressure it elicits in baroreceptor-intact rats. This could result either from a lack of tonic excitatory input to this region or from overriding inhibition of NTS neurons involved in the control of blood pressure. The present study aimed to distinguish between these two possibilities by examining the changes in blood pressure elicited by injection of bicuculline (Bic), a gamma-aminobutyric acid (GABA) antagonist, into the NTS of SAD and control rats. In chloralose-anesthetized baroreceptor-intact rats or acutely SAD rats, injection of 10 pmol Bic into the NTS elicited minimal changes in blood pressure. In contrast, in chronic SAD rats injection of Bic into the NTS elicited a large decrease in blood pressure. The maximal decrease in blood pressure elicited by Bic in chronic SAD rats was equivalent to the maximal decrease in blood pressure that could be evoked by direct excitation of the NTS with L-glutamate. These results suggest that the lack of a tonic role of the NTS in the regulation of blood pressure in chronic SAD rats is a result of maximal GABA-mediated inhibition of relevant NTS neurons. PMID- 9374807 TI - Muramyl dipeptide and IL-1 effects on sleep and brain temperature after inhibition of serotonin synthesis. AB - The role of the interactions between serotonin (5-HT) and muramyl dipeptide (MDP) and interleukin-1 (IL-1) in sleep control and thermoregulation was evaluated. To this purpose, MDP and IL-1 were injected intracerebroventricularly at dark onset into freely moving rats pretreated twice intraperitoneally with para chlorophenylalanine (PCPA) (300 mg/kg), which depletes brain 5-HT and causes insomnia. Fever and slow-wave sleep (SWS) enhancement induced by 150 pmol MDP were completely blocked in PCPA-pretreated rats. Only the first phase of the biphasic increase in SWS induced by 2.5 ng IL-1 was suppressed by PCPA pretreatment, whereas fever remained unaffected. These results suggest that 1) MDP effects on both sleep-wake activity and brain cortical temperature are mediated by the serotonergic system; 2) the mechanisms mediating the first and the second phases of IL-1-induced SWS excess are different: 5-HT could be involved in the first phase, but not in the second one; and 3) the 5-HT system does not appear to be involved in IL-1-induced fever. PMID- 9374808 TI - Prenatal dexamethasone exposure alters brain monoamine metabolism and adrenocortical response in rat offspring. AB - In this study, it has been clearly demonstrated that prenatal dexamethasone treatment (Dex; 0.05 mg/kg on gestational days 17, 18, and 19) resulted in the significant reductions of 5-hydroxytryptamine (5-HT) turnover in four brain regions, including the neocortex, hippocampus, hypothalamus, and midbrain + pons medulla (M + P-M) but not in the striatum in the offspring at 3 and 14 wk of life, as well as dopamine turnover in the hypothalamus. [3H]paroxetine binding densities were increased in the hypothalamus and M + P-M at 14 wk of life, which corresponded to increased 5-HT contents in both regions. On the other hand, significantly lower norepinephrine contents in the neocortex and hippocampus were observed in the Dex group compared with the control group at 14 wk of life. In addition, the exposure to new environmental condition elevated blood corticosterone levels and enhanced behavioral activities to a greater extent in the Dex group than in controls at 7 wk of life, suggesting that elevated glucocorticoid levels during the pregnancy mimicked prenatal mild stress, producing developmental alterations in brain monoamine metabolism, endocrine response, and behavior in adult offspring. PMID- 9374809 TI - Effect of interactions between nitric oxide and angiotensin II on pressure diuresis and natriuresis. AB - The present study examined the effect of an angiotensin II AT1 or AT2 receptor antagonist on the impairment of the pressure diuresis and natriuresis response produced by nitric oxide (NO) synthesis blockade. N omega-nitro-L-arginine methyl ester (L-NAME, 37 nmol.kg-1.min-1) lowered renal blood flow and reduced the slopes of the pressure diuresis and natriuresis responses by 44 and 40%, respectively. Blockade of AT1 receptors with valsartan increased slightly sodium and water excretion at low renal perfusion pressure (RPP). Blockade of AT2 receptors with PD-123319 had no effect on renal function. The administration of valsartan or PD-123319 to rats given L-NAME had no effect on the renal vasoconstriction induced by NO synthesis blockade. In addition, in rats given L NAME, valsartan elevated baseline excretory values at all RPP studied, but it had no effect on the sensitivity of the pressure diuresis and natriuresis response. However, the administration of PD-123319 to L-NAME-pretreated rats shifted the slopes of the pressure diuresis and natriuresis responses toward control values, indicating that the impairment produced by NO synthesis blockade on pressure diuresis is dependent on the activation of AT2 angiotensin receptors. PMID- 9374810 TI - Amygdala but not hippocampal lesions impair olfactory memory for mate in prairie voles (Microtus ochrogaster). AB - Exposure to an unfamiliar male conspecific results in pregnancy interruption (i.e., the Bruce effect) in rodents. Unlike most laboratory rodents, female prairie voles (Microtus ochrogaster) are induced into estrus by chemosensory stimuli contained in the urine of male conspecifics while grooming the anogenital (A-G) region of unfamiliar males. Female prairie voles maintain a brief "memory" for the stud male for 8-10 days after mating. Subsequent exposure to the same mate within this 8- to 10-day window does not elicit A-G investigation by the female and pregnancy block does not result. However, exposure to the original male after 10 days evokes A-G investigation and pregnancy block. To determine the neuroanatomic area(s) involved in olfactory memory for mate, female voles received bilateral electrolytic lesions of either the amygdala or hippocampus. Females were subsequently exposed to males for 48 h, separated for 3 days, then reintroduced to their original mate for 24 h. Although pregnancy rate did not differ among the experimental groups, a greater proportion of amygdala-lesioned females displayed pregnancy block when reexposed to their previous mates compared with hippocampal- or sham-lesioned voles. Amygdala-lesioned voles also displayed a greater number of A-G investigations compared with the other groups. Performance on olfactory tests was not impaired. Taken together, these results suggest that the amygdala plays an important role in olfactory memory for mate in prairie voles. PMID- 9374811 TI - Circumventricular organs and fever. AB - We have examined the roles of three circumventricular organs, the area postrema, the subfornical organ, and the organum vasculosum of the lamina terminalis (OVLT), as possible access points for circulating pyrogens to cause fever. In conscious, unrestrained rats prepared with telemetry devices, intracerebroventricular cannulas, and intravenous catheters, body temperature was monitored after intravenously administered lipopolysaccharide and, on a different occasion, after intracerebroventricular prostaglandin E1. Lipopolysaccharide induced fevers in sham control lesioned rats were indistinguishable from those observed in animals with lesions of the area postrema, the OVLT, or the tissue immediately adjacent to this structure (peri-OVLT). In contrast, rats with lesions of the subfornical organ displayed reduced fevers. In none of the groups of lesioned animals were prostaglandin E1 fevers reduced. Thus lesions did not interfere with central thermogenic pathways responsive to prostaglandin. Our results indicate that subfornical organ neurons respond to circulating pyrogens and through their efferent projections activate central pathways involved in fever. PMID- 9374812 TI - Long-term effects of AVP-induced neurohumoral interaction via area postrema on body fluid and blood pressure. AB - Arginine vasopressin (AVP) has been known to interact with the central nervous system via the area postrema (AP), resulting in suppression of renal sympathetic outflow in short-term studies. We hypothesize that if this sympathoinhibitory effect lasts long, then the neurohumoral interaction would enhance urinary output because of the suppression of neurogenic reuptake of sodium (Na+) and water. Intact (Int) and AP-lesioned (APX) rabbits were chronically catheterized and housed in metabolic cages. AVP was intravenously infused (0.1 mU.kg-1.min-1) for 5 consecutive days. Urine volume and urinary Na+ excretion rates in Int rabbits were lower than those in APX rabbits during AVP infusion. This smaller urinary output in Int rabbits was reconfirmed either from the daily balance of water and Na+ or from the body weight, plasma Na+ concentration, and plasma osmolality data. This result contradicted the hypothesis. Mean arterial pressure was not altered in either group of rabbits while heart rate was suppressed in the Int rabbits. These data suggest that AP-mediated long-term action of AVP augments water retention and sustains bradycardia. PMID- 9374813 TI - DHEA protects against visceral obesity and muscle insulin resistance in rats fed a high-fat diet. AB - Visceral obesity is frequently associated with muscle insulin resistance. Rats fed a high-fat diet rapidly develop obesity and insulin resistance. Dehydroepiandrosterone (DHEA) has been reported to protect against the development of obesity. This study tested the hypothesis that DHEA protects against the increase in visceral fat and the development of muscle insulin resistance induced by a high-fat diet in rats. Feeding rats a diet providing 50% of the energy as fat for 4 wk resulted in a twofold greater visceral fat mass and a 50% lower rate of maximally insulin-stimulated muscle 2-deoxyglucose (2-DG) uptake compared with controls. Rats fed the high-fat diet plus 0.3% DHEA were largely protected against the increase in visceral fat (+ 11.3 g in high fat vs. + 2.9 g in high fat plus DHEA, compared with controls) and against the decrease in insulin-stimulated muscle 2-DG uptake (0.94 +/- 0.15 mumol.ml-1.20 min-1, controls; 0.46 +/- 0.06 mumol.ml-1.20 min-1, high-fat diet; 0.78 +/- 0.07 mumol.ml-1.20 min-1, high fat + DHEA). DHEA did not affect food intake. These results show that DHEA has a protective effect against accumulation of visceral fat and development of muscle insulin resistance in rats fed a high-fat diet. PMID- 9374814 TI - Sepsis-induced depression of rat glucose-6-phosphatase gene expression and activity. AB - Sepsis in rats decreases the hepatic expression of the gluconeogenic enzyme glucose-6-phosphatase (G6Pase). The aim of this study was to investigate the relationship among G6Pase transcription, mRNA, enzymatic activity, and serum glucose levels at different intervals during mild or fulminant sepsis. Both fulminant and mild sepsis immediately decreased hepatic G6Pase mRNA levels. In mild sepsis, levels began to recover late in the time course. Serum glucose levels were maintained in mild sepsis but decreased markedly in fulminant sepsis. G6Pase transcription after fulminant sepsis decreased and never recovered. A similar transcriptional decrease was noted in mild sepsis, but some recovery occurred in this state. Histochemistry after mild sepsis revealed a decrease in G6Pase protein and enzymatic activity that paralleled transcription. These studies suggest that changes in G6Pase transcription and activity are early markers for sepsis-induced alterations in hepatic function. Mechanisms other than gene expression and enzymatic activity serve to maintain glucose levels in mild sepsis, but in the fulminant disorder, compensatory mechanisms fail and hypoglycemia develops. PMID- 9374816 TI - Low urine flow reduces the capacity to excrete a sodium load in humans. AB - Recent studies in rats suggest that vasopressin and the resulting urinary concentrating activity reduce the capacity of the kidney to excrete sodium. The present study investigates the influence of the level of hydration on the excretion of a sodium load in humans. Eight healthy male volunteers (18-35 yr) were studied twice, in random order, under either low (LowH) or high (HighH) hydration. They drank throughout the study either 0.25 (LowH) or 2.0 ml water/kg body wt (HighH) every 30 min. After 1 h equilibration, urine was collected for 2 h before (basal) and 10 h after the NaCl load (5 g NaCl in 250 ml, infused intravenously over 30 min). Differences in excretory patterns between LowH and HighH were mostly confined to the first 4 h after the load. The increase in Na excretion after the load was more intense under HighH than under LowH (+ 10.9 +/- 2.6 vs. + 5.8 +/- 2.7 mmol/h in the first 4 postload h; P < 0.001). Under HighH, urine flow rate (V) increased markedly (+ 41%), with little change in urinary Na concentration (UNa), whereas under LowH, V declined slightly and UNa rose significantly (+ 33%). The capacity to raise UNa seemed to reach a maximum at approximately 280 mM. In both conditions, the changes in UNa observed after the load were positively correlated with basal UNa. After the load, urea excretion increased under HighH and decreased under LowH, whereas K excretion was unaffected in either condition. These results show that sodium excretion is facilitated by an abundant water supply. The less efficient sodium excretion occurring at low V is probably due to the influence of vasopressin on water, urea, and sodium movements across the collecting ducts. These observations suggest that, in everyday life, a low water intake could limit the capacity to excrete sodium. Whether this could contribute to salt-sensitive hypertension remains to be evaluated. PMID- 9374815 TI - pH-dependent proton secretion in cultured swim bladder gas gland cells. AB - The pH dependence of acid production and of acid release has been analyzed in cultured gas gland cells of the European eel using a cytosensor microphysiometer. Total acid release of gas gland cells showed an optimum at pH 7.4-7.6, with only a minor reduction at acidic (pH 7.0) as well as at alkaline pH (pH 8.0). The acid production was largely dependent on the availability of extracellular glucose and was almost completely abolished if glucose was replaced by succinate, alanine, or even pyruvate. Phloretin, an inhibitor of glucose uptake, significantly reduced acid release of gas gland cells with a Ki of approximately 1 x 10(-5) M, irrespective of pH. Although the glucose dependence of acid production was not modified by pH, acid release became increasingly sodium dependent with decreasing pH, but at low pH significantly higher sodium concentrations were necessary to achieve maximal rate of proton secretion. This sodium-dependent proton secretion could only in part be inhibited by application of 5-(N-methyl-N-isobutyl) amiloride. Removal of extracellular potassium caused a slow reduction in the rate of acid secretion. A similar reduction was observed in the presence of ouabain, a specific inhibitor of Na(+)-K(+)-adenosinetriphosphatase, and both effects significantly increased with decreasing pH. The results demonstrate a significant pH dependence of the mechanisms of acid release in swim bladder gas gland cells and indicate that sodium-dependent pathways become especially important at low pH. PMID- 9374817 TI - Effect of chronic hypoxia on glucose transporters in heart and skeletal muscle of immature and adult rats. AB - Glucose transporter (GLUT) modulation can be an important mechanism that contributes to adaptation to hypoxic stress, but little is known about GLUT modulation in heart and skeletal muscle with prolonged hypoxia. In this work, the effect of chronic hypoxia on GLUT-4 and GLUT-1 mRNA and protein was studied in these two tissues in the adult and during development. Hypoxia (fractional inspired O2 = 9 +/- 0.5%) was administered to two groups, i.e., an immature group exposed from 3 to 30 days of age and an adult group exposed from 90 to 120 days of age. Rats were then killed and their heart and skeletal muscles were sampled for measurements of GLUT mRNA and protein with Northern and Western blots. In the adult, chronic hypoxia significantly decreased cardiac GLUT mRNA level by > 25% of control (P < 0.05), but had little effect on GLUT protein. A very different hypoxic effect was seen in the immature rat heart with a major increase in protein and no appreciable change in mRNA density. Adult skeletal muscle had no change in GLUT mRNA level but GLUT protein increased (15-20%, P < 0.05) while both GLUT mRNA and protein were significantly increased in the immature skeletal muscles (60-90% over control). We conclude that during chronic O2 deprivation, GLUT-1 and GLUT-4 expressions show a similar pattern but greatly depend on tissue type and age. These differences in GLUT regulation may be due to different strategies for coping with prolonged O2 deprivation in both immature and adult animals. PMID- 9374818 TI - Evidence for the presence of smooth muscle alpha-actin within pericytes of the renal medulla. AB - This study was designed to determine whether smooth muscle alpha-actin mRNA and smooth muscle alpha-actin contractile protein elements were present within the renal medullary pericytes. Extraction of total RNA from microdissected outer medullary descending vasa recta allowed for the detection of smooth muscle alpha actin mRNA expression using reverse transcription-polymerase chain reaction (RT PCR). Expression of smooth muscle alpha-actin was specific to the descending vasa recta and not a result of tubular contamination because RT-PCR amplification of the vasopressin V2 receptor, which is a specific tubular marker, did not occur. To determine the exact cell type(s) that translate the mRNA into protein, we performed immunohistochemistry on the renal outer and inner medulla using a monoclonal smooth muscle alpha-actin antibody, whose specificity was determined by immunoblot analysis. Smooth muscle alpha-actin protein was found selectively within the pericytes surrounding the descending vasa recta from the outer and inner medullary tissue sections. This study demonstrates that the pericytes alone that surround the descending vasa recta within the outer and inner medulla contain smooth muscle alpha-actin mRNA and protein and are therefore the site of the contractile elements that could play a vasomodulatory role in the control of renal medullary blood flow and its distribution within the renal medulla. PMID- 9374819 TI - Neural regulation of kidney function by the somatosensory system in normotensive and hypertensive rats. AB - This investigation examined the renal sympathetic nerve and renal excretory responses to somatosensory stimulation in normotensive and stroke-prone spontaneously hypertensive rats (SHRSP). Somatosensory activation was achieved by either subcutaneous capsaicin administration or exposure of the airways tract to irritant fumes from acetic acid in chloralose-urethan-anesthetized animals. In Wistar rats, blood pressure increased between 10 and 20% (P < 0.001-0.01), renal perfusion pressure was maintained unchanged, renal hemodynamics were unaltered, and urine flow and sodium excretion were decreased by 25 to 50% (P < 0.001-0.05). In the SHRSP, the somatosensory-induced increases in blood pressure were slightly larger (approximately 15-20% P < 0.05) than those of the Wistar rats, whereas the excretory responses were one-half those of the normotensive animals (P < 0.05). The somatosensory challenges reflexly increased integrated renal sympathetic nerve activity in both normotensive and hypertensive rats. The power spectral analysis demonstrated that the increases in percentage power at heart rate frequency and total power were two to three times more (P < 0.05) in the Wistar rats compared with the SHRSP. The reduced ability of the SHRSP to modulate the energy in the renal sympathetic nerve signal at heart rate frequency might explain in part the attenuated functional responses to the somatosensory challenges. PMID- 9374820 TI - Adrenal epinephrine and norepinephrine release to hypoglycemia measured by microdialysis in conscious rats. AB - Experiments were conducted in conscious male rats to determine whether hypoglycemia induced by insulin administration preferentially stimulated epinephrine (Epi) or norepinephrine (NE) adrenal medullary chromaffin cells. The release of Epi and NE from the adrenal medulla was continuously monitored using a microdialysis probe of novel design that had been inserted in the adrenal medulla approximately 16 h before the administration of insulin. Following insulin, 3 U/kg i.v., blood glucose declined and dialysate Epi levels rose. No measurable increment in dialysate NE was obtained. Similarly, plasma Epi increased with no detectable change in NE. Patterns of dialysate and plasma catecholamine changes were similar in two groups of animals that had been fed or fasted overnight before insulin treatment. However, the magnitude of the Epi increase was greater in the fasted animals. After recovery of the blood glucose concentration to preinsulin levels, dialysate and plasma catecholamine concentrations returned to control values. These experiments clearly demonstrate that adrenal medullary chromaffin cells that produce Epi are preferentially stimulated in response to insulin-induced hypoglycemia. PMID- 9374821 TI - Fetal grafts containing suprachiasmatic nuclei restore the diurnal rhythm of CRH and POMC mRNA in aging rats. AB - We assessed whether fetal tissue containing the suprachiasmatic nuclei (SCN) can restore age-related changes in the diurnal rhythm of hypothalamic corticotropin releasing hormone (CRH) and anterior pituitary proopiomelanocortin (POMC) mRNA. Young, middle-aged, and middle-aged SCN-transplanted rats were killed at seven times of day. In young rats, CRH mRNA exhibited a diurnal rhythm in the dorsomedial paraventricular nuclei but not in other subdivisions of the nuclei. No rhythm was detected in aging rats. SCN transplants restored a rhythm in CRH mRNA, but the timing was not precisely the same as in young animals. POMC mRNA exhibited a daily rhythm in young rats. Aging abolished the rhythm and decreased the average mRNA level; fetal transplants restored the rhythm, but the amplitude remained attenuated. These data are the first demonstration that fetal tissue can restore the diurnal rhythm of a neuroendocrine axis that is driven by the SCN. We conclude that the neuroendocrine substrate from the aging host remains capable of responding to diurnal cues to express diurnal rhythmicity in CRH/POMC mRNA when fetal SCN transplants confer the appropriate signals. PMID- 9374822 TI - Protection against glutamate-induced cytotoxicity in C6 glial cells by thiol antioxidants. AB - In many cell lines, glutamate cytotoxicity is known to be medicated by an inhibition of cystine transport. Because glutamate and cystine share the same transporter, elevated levels of extracellular glutamate competitively inhibit cystine transport leading to depletion of intracellular glutathione. A glutathione-depleted state impairs cellular antioxidant defenses resulting in oxidative stress. It was therefore of interest to investigate whether proglutathione agents, e.g., N-acetylcysteine and lipoic acid, are able to protect against glutamate cytotoxicity. Both lipoic acid (100 microM-1 mM) and N acetylcysteine (100 microM-1 mM) completely protected C6 cells from the glutamate induced cell death. Both agents facilitate extracellular supply of cysteine, the reduced form of cystine, that is transported into the cell by a glutamate insensitive transport mechanism. Protection by lipoic acid and N-acetylcysteine corresponded with a sparing effect on cellular glutathione, which is usually depleted after glutamate treatment. In the presence of L-buthionine-(S,R) sulfoximine, a gamma-glutamylcysteine synthetase inhibitor, low doses (< 100 microM) of lipoic acid and N-acetylcysteine did not protect cells against glutamate-induced cytotoxicity. At higher concentrations (> 500 microM), however, both lipoic acid and N-acetylcysteine provided partial protection against glutamate cytotoxicity even in glutathione synthesis-arrested cells. These results indicate that at low concentrations the primary mechanism of protection by the thiol antioxidants was mediated by their proglutathione property rather than direct scavenging of reactive oxygen. At higher concentrations (> 500 microM), a GSH-independent direct antioxidant effect of lipoic and N acetylcysteine was observed. Dichlorofluorescin fluorescence, a measure of intracellular peroxides, increased sixfold after glutamate treatment of C6 cells. Lipoic acid and N-acetylcysteine treatment significantly lowered glutamate induced dichlorofluorescin fluorescence compared with that of controls. Interestingly, alpha-tocopherol (50 microM) also suppressed glutamate-induced dichlorofluorescin fluorescence, indicating the peroxides detected by dichlorofluorescin were likely lipid hydroperoxides. Both thiol antioxidants, particularly lipoic acid, appear to have remarkable therapeutic potential in protecting against neurological injuries involving glutamate and oxidative stress. PMID- 9374824 TI - Gastric branch vagotomy and gastric emptying during and after intragastric infusion of glucose. AB - The effect of gastric branch vagotomy (GVX) on the gastric emptying of glucose was evaluated during two phases of emptying control: as the stomach fills and in the postload period. GVX and control rats received a series of intragastric glucose infusions (1.0 ml/min) through indwelling gastric fistulas. In experiment 1, gastric samples were withdrawn either immediately after the offset of 9- or 18 min infusions of 12.5% glucose or at various times up to 36 min postinfusion. In experiment 2, samples were withdrawn either immediately or 30 min after termination of 12-min infusions of 12.5 or 25% glucose. After gastric fill, glucose solute emptying rate was stable over time not influenced by concentration doubling, and, surprisingly, not affected by GVX. During gastric fill, solute emptying rate doubled with concentration in both GVX and control rats. For each concentration, however, glucose emptied during fill at almost twice the rate in GVX compared with control rats. This accelerated emptying of glucose during fill in GVX rats is consistent with a gastric vagal contribution to inhibitory mechanisms (e.g., receptive relaxation) that operate as the stomach fills under normal conditions. The absence of a GVX effect on emptying after fill suggests either that gastric branch vagal efferents play little role in feedback inhibitory control of glucose emptying under normal conditions or that other systems compensate for the function previously served by vagal gastric branch efferents. Further work is required to address the possible role of the gastric vagus in feedback control of gastric emptying when nutritive fluids other than glucose are delivered. PMID- 9374823 TI - Satiety from fat? Adverse effects of intestinal infusion of sodium oleate. AB - To determine whether damage to the intestinal mucosa by oleic acid causes the suppression of food intake observed in response to intraintestinal infusion of the fatty acid, we measured lactate dehydrogenase (LDH) activity, a marker for cell damage, in the intestinal lumen after intestinal infusion of fatty acid under conditions similar to those employed in studies of eating behavior. Infusions of 25 or 51 mM sodium oleate (neutralized oleic acid) markedly and rapidly increased LDH activity, whereas infusions of saline had little or no effect. Infusion of octanoate, which has been reported to be ineffective in reducing eating behavior, did not increase intestinal LDH activity relative to saline infusion. Similarly, infusion of ethyl oleate or free (nonneutralized) oleic acid neither increased luminal LDH activity nor suppressed food intake. Infusion of sodium oleate also produced a strong conditioned aversion to sucrose. The results strongly suggest that the suppression of food intake induced by intraintestinal infusion of sodium oleate is due to the injurious effects of this unphysiological form of the fatty acid. PMID- 9374825 TI - Pivotal role of the renin-angiotensin system in Lyon hypertensive rats. AB - We assessed the role of the renin-angiotensin system (RAS) in Lyon genetically hypertensive (LH) and normotensive (LN) rats by measuring 1) kidney renin and prorenin contents; 2) effects of early, prolonged angiotensin-converting enzyme (ACE) inhibition on blood pressure (BP) and regional hemodynamics; and 3) acute and chronic responses to angiotensin II (ANG II) and norepinephrine (NE). At the adult age, LH rats differed from LN rats by elevated BP, left ventricle weight, and vascular resistances, especially in the kidneys, associated with lower kidney renin and prorenin contents. ACE inhibition (perindopril, 3 mg.kg-1.24 h-1 orally from 3 to 15 wk of age) suppressed the development of hypertension, cardiac hypertrophy, and the increase in renal vascular resistances. No specific hypersensitivity to ANG II could be disclosed in acute conditions. In perindopril treated LH rats, a 4-wk infusion of ANG II (200 ng.kg-1.min-1) but not of NE (1,000 ng.kg-1.min-1) restored hypertension, mimicked the hemodynamic alterations seen in untreated LH rats, and produced a brief sodium retention. It is concluded that in LH rats, despite a low basal renin secretion, hypertension and hemodynamic abnormalities 1) are fully dependent on an active RAS and 2) may involve an enhanced sensitivity to the chronic effects of ANG II. PMID- 9374826 TI - Human circadian pacemaker is sensitive to light throughout subjective day without evidence of transients. AB - Fifty-six resetting trials were conducted across the subjective day in 43 young men using a three-cycle bright-light (approximately 10,000 lx). The phase response curve (PRC) to these trials was assessed for the presence of a "dead zone" of photic insensitivity and was compared with another three-cycle PRC that had used a background of approximately 150 lx. To assess possible transients after the light stimulus, the trials were divided into 43 steady-state trials, which occurred after several baseline days, and 13 consecutive trials, which occurred immediately after a previous resetting trial. We found that 1) bright light induces phase shifts throughout subjective day with no apparent dead zone; 2) there is no evidence of transients in constant routine assessments of the fitted temperature minimum 1-2 days after completion of the resetting stimulus; and 3) the timing of background room light modulates the resetting response to bright light. These data indicate that the human circadian pacemaker is sensitive to light at virtually all circadian phases, implying that the entire 24-h pattern of light exposure contributes to entrainment. PMID- 9374827 TI - A finite element model for predicting the distribution of drugs delivered intracranially to the brain. AB - Drug therapy to the central nervous system is complicated by the presence of the blood-brain barrier. The development of new drug delivery techniques to overcome this obstacle will be aided by a clear understanding of the transport processes in the brain. A rigorous theoretical framework of the transport of drugs delivered locally to the parenchyma has been developed using the finite element method. Magnetic resonance imaging has been used to track the transport of paramagnetic contrast markers in the brain. The information obtained by postprocessing spin-echo, T1-weighted, and proton density images has been used to refine the mathematical model that includes realistic brain geometry and salient anatomic features and allows for two-dimensional transport of chemical species, including both diffusive and convective contributions. In addition, the effects of regional differences in tissue properties, ventricular boundary, and edema on the transport have been considered. The model has been used to predict transport of interleukin-2 in the brain and study the major determinants of transport, at both early and late times after drug delivery. PMID- 9374829 TI - Perfusion pressure dependency of in vivo renal tubular dynamics. AB - To examine whether changes in renal perfusion pressure (RPP) within the range of autoregulation induce detectable changes in tubular dynamics in an entire nephron population of the intact kidney, we measured, using electron beam computed tomography (EBCT), transit times (TT, s) and intratubular concentration (%) of filterable contrast media in various nephron segments simultaneously with renal regional perfusion. In seven dogs (group A) this was performed at the upper and lower limits of autoregulation (RPP = 130 and 95 mmHg, respectively) while group B (n = 5) served as control. In group A alone, a decrease in RPP led to an increase in TT by 40%, 68%, and 32% in the proximal tubules, ascending limb of Henle's loop, and distal tubules, respectively, in association with an increase in intratubular concentration (+ 50%, 80%, and 42%, respectively). Papillary perfusion decreased, whereas perfusion of the adjacent, outlying inner medulla increased. The decrease in papillary perfusion correlated positively with the concurrent change in sodium excretion (R = 0.81). This study demonstrates that changes in RPP within the autoregulatory range elicit changes of tubular sodium reabsorption mainly in proximal, distal, and ascending tubules, in which most of the nephrons participate. These tubular changes are associated with an alteration of perfusion circumscribed to two areas of the inner renal medulla. PMID- 9374828 TI - Interleukin-1 beta switches electrophysiological states of synovial fibroblasts. AB - The role of electro-physiological events in signal transduction of interleukin-1 beta (IL-1 beta) was investigated in rabbit synovial fibroblasts using the perforated-patch method. Aggregated synovial fibroblasts using the perforated patch method. Aggregated synovial fibroblasts occurred in two different electrophysiological states having membrane potentials (Vm) of -63 +/- 4 (n = 71) and -27 +/- 10 mV (n = 55) (high and low Vm, respectively). IL-1 beta affected the cells with high Vm; it switched the state of the cell from high to low Vm. This effect was strongly dependent on the external potential applied to the cell membrane. Low Vm (-30 mV) alone without IL-1 beta did not switch the state of the cells. Thus a synergistic effect involving the cytokine and cell Vm in switching the electrophysiological state of the cell was shown, indicating that electrophysiological changes are involved in signal transduction. Gap junctions between aggregated cells were necessary for the cells to have a high Vm and to respond to IL-1 beta. Gap junction resistance between adjacent cells was estimated as 300 +/- 100 M omega. Our findings suggest that the electrophysiological behavior of synovial fibroblasts is tightly connected to a signaling or intracellular mediator system that is triggered by IL-1 beta. PMID- 9374830 TI - Inhibition of PAH transport by parathyroid hormone in OK cells: involvement of protein kinase C pathway. AB - We have previously shown that the p-aminohippurate (PAH) transport system in OK kidney epithelial cell line is under the regulatory control of protein kinase C. Parathyroid hormone (PTH) could activate protein kinase C, as well as protein kinase A, in OK cells. In the present study, the effect of PTH on PAH transport was studied in OK cells. PTH inhibited the transcellular transport of PAH from the basal to the apical side, as well as the accumulation of PAH in OK cells. Basolateral PAH uptake was inhibited by PTH in a dose- and time-dependent manner. Protein kinase A activators did not affect the transcellular transport or the accumulation of PAH. The PTH-induced inhibition of the accumulation of PAH was blocked by a protein kinase C inhibitor staurosporine. These results suggest that PTH inhibits the PAH transport in OK cells and that the messenger system mediated by protein kinase C, not protein kinase A, plays an important role in the regulation of PAH transport by PTH. PMID- 9374831 TI - Cl- and K+ conductances activated by cell swelling in primary cultures of rabbit distal bright convoluted tubules. AB - Ionic currents induced by cell swelling were characterized in primary cultures of rabbit distal bright convoluted tubule (DCTb) by the whole cell patch-clamp technique. Cl- currents were produced spontaneously by whole cell recording with an isotonic pipette solution or by exposure to a hypotonic stress. Initial Cl- currents exhibited outwardly rectifying current-voltage relationship, whereas steady-state currents showed strong decay with depolarizing pulses. The ion selectivity sequence was I- = Br- > Cl- >> glutamate. Currents were inhibited by 0.1 mM 5-nitro-2-(3-phenylpropylamino) benzoic acid and 1 mM 4,4' diisothiocyanostilbene-2,2'-disulfonic acid and strongly blocked by 1 mM diphenylamine-2-carboxylate. Currents were insensitive to intracellular Ca2+ but required the presence of extracellular Ca2+. They were not activated in cells pretreated with 200 nM staurosporine, 50 microM LaCl3, 10 microM nifedipine, 100 microM verapamil, 5 microM tamoxifen, and 50 microM dideoxyforskolin. Staurosporine, tamoxifen, verapamil, or the absence of external Ca2+ was without effect on the fully developed Cl- currents. Osmotic shock also activated K+ currents in Cl- free conditions. These currents were time independent, activated at depolarized potentials, and inhibited by 5 mM BaCl2. The activation of Cl- and K+ currents by an osmotic shock may be implicated in regulatory volume decrease in DCTb cells. PMID- 9374832 TI - The effects of respiratory alkalosis and acidosis on net bicarbonate flux along the rat loop of Henle in vivo. AB - We have studied the effects of acute respiratory alkalosis (ARALK, hyperventilation) and acidosis (ARA, 8% CO2), chronic respiratory acidosis (CRA; 10% CO2 for 7-10 days), and subsequent recovery from CRA breathing air on loop of Henle (LOH) net bicarbonate flux (JHCO3) by in vivo tubule microperfusion in anesthetized rats. In ARALK blood, pH increased to 7.6, and blood bicarbonate concentration ([HCO3-]) decreased from 29 to 22 mM. Fractional urinary bicarbonate excretion (FEHCO3) increased threefold, but LOH JHCO3 was unchanged. In ARA, blood pH fell to 7.2, and blood [HCO3-] rose from 28 to 34 mM; FEHCO3 was reduced to < 0.1%, but LOH JHCO3 was unaltered. In CRA, blood pH fell to 7.2, and blood [HCO3-] increased to > 50 mM, whereas FEHCO3 decreased to < 0.1%. JHCO3 was reduced by approximately 30%. Bicarbonaturia occurred when CRA rats breathed air, yet LOH JHCO3 increased (by 30%) to normal. These results suggest that LOH JHCO3 is affected by the blood-to-tubule lumen [HCO3-] gradient and HCO3- backflux. When the usual perfusing solution at 20 nl/min was made HCO3- free, mean JHCO3 was -34.5 +/- 4.4 pmol/min compared with 210 +/- 28.1 pmol/min plus HCO3-. When a low-NaCl perfusate (to minimize net fluid absorption) containing mannitol and acetazolamide (2 x 10(-4) M, to abolish H(+)-dependent JHCO3) was used, JHCO3 was -112.8 +/- 5.6 pmol/min. Comparable values for JHCO3 at 10 nl/min were -35.9 +/- 5.8 and -72.5 +/- 8.8 pmol/min, respectively. These data indicate significant backflux of HCO3-along the LOH, which depends on the blood-to-lumen [HCO3-] gradient; in addition to any underlying changes in active acid-base transport mechanisms, HCO3- permeability and backflux are important determinants of LOH JHCO3 in vivo. PMID- 9374834 TI - Attenuated response of renal mechanoreceptors to volume expansion in chronically hypoxic rats. AB - Multifiber renal afferent nerve activity responds to volume expansion in sea level rats but not in chronically hypoxic (high altitude) rats. We performed single-unit recordings of renal afferent nerve activity to characterize renal sensory receptors and their responses to volume expansion in these animals. Hypoxia was induced by placing Wistar rats in an altitude chamber (380 Torr, 5,500 m) for 4 wk. Spontaneously firing renal R2 chemoreceptor and arterial, ureteropelvic, and venous mechanoreceptors were identified. The basal activity of each receptor was similar among these rats. In response to specific stimulus, the increasing impulse of R2 chemoreceptor was similar between two groups of rats, but the increasing activity of each mechanoreceptor was less in hypoxic rats. When challenged with saline load, R2 chemoreceptor activity decreased, but all mechanoreceptors activated in all rats. Despite similar increases of arterial, renal ureteropelvic, and venous pressure during saline load, the increasing activity of each mechanoreceptor was significantly less in hypoxic rats. These results indicated chronic hypoxia attenuates the sensitivity of renal mechanoreceptors in response to the stimulation of saline load. PMID- 9374833 TI - Recognition of beta-lactam antibiotics by rat peptide transporters, PEPT1 and PEPT2, in LLC-PK1 cells. AB - PEPT1 and PEPT2 are H(+)-coupled peptide transporters expressed preferentially in the intestine and kidney, respectively, which mediate uphill transport of oligopeptides and peptide-like drugs such as beta-lactam antibiotics. In the present study, we have compared the recognition of beta-lactam antibiotics by LLC PK1 cells stably transfected with PEPT1 or PEPT2 cDNA. Cyclacillin (aminopenicillin) and ceftibuten (anionic cephalosporin without an alpha-amino group) showed potent inhibitory effects on the glycylsarcosine uptake in the PEPT1-expressing cells. Other beta-lactams, such as cephalexin, cefadroxil, and cephradine (aminocephalosporins), inhibited modestly the PEPT1-mediated glycylsarcosine uptake. Except for ceftibuten, these beta-lactams showed much more potent inhibitions on the glycylsarcosine uptake via PEPT2 than via PEPT1. Comparison of the inhibition constant (Ki) values between cefadroxil and cephalexin suggested that the hydroxyl group at the NH2-terminal phenyl ring increased affinity for both PEPT1 and PEPT2. It is concluded that PEPT2 has a much higher affinity for beta-lactam antibiotics having an alpha-amino group than PEPT1 and that substituents at the NH2-terminal side chain of these drugs are involved in the recognition by both peptide transporters. PMID- 9374835 TI - Expression of syntaxins in rat kidney. AB - Previously, we demonstrated that a putative vesicle-targeting protein, syntaxin 4, is expressed in renal collecting duct principal cells and is localized to the apical plasma membrane, suggesting a role in targeting aquaporin-2-containing vesicles to the apical plasma membrane. To investigate whether other syntaxin isoforms are present in the renal collecting duct, we determined the intrarenal localization of syntaxin-2 and -3. Reverse transcription-polymerase chain reaction (RT-PCR) experiments using total RNA extracted from kidney and various organs revealed that both syntaxin-2 and -3 are expressed in kidney cortex and medulla. RT-PCR experiments using microdissected tubules and vascular structures from the kidney revealed that syntaxin-3 mRNA, but not syntaxin-2, is expressed in collecting duct cells. Syntaxin-3 mRNA was also relatively abundant in the thick ascending limb of Henle's loop and in vasa recta. Syntaxin-2 mRNA was found chiefly in glomeruli. To investigate the localization of syntaxin-3 protein, a peptide-derived polyclonal antibody was raised in rabbits. In immunoblotting experiments, this antibody labeled a 37-kDa protein in inner medulla that was most abundant in plasma membrane-enriched subcellular fractions. Immunoperoxidase labeling of thin cryosections combined with immunogold electron microscopy showed that, in contrast to the labeling seen for syntaxin-4, syntaxin-3 labeling in medullary collecting duct was predominantly in the basolateral plasma membrane of intercalated cells. These results suggest the possibility that syntaxin-3 may be involved in selective targeting of acid-base transporters and/or in basolateral membrane remodeling in response to systemic acid-base perturbations. PMID- 9374836 TI - Zis: a developmentally regulated gene expressed in juxtaglomerular cells. AB - Renal juxtaglomerular (JG) cells are specialized myoepithelioid cells located in the afferent arteriole at the entrance to the glomerulus. Their main function and distinctive feature is the synthesis and release of renin, the key hormone-enzyme of the renin-angiotensin system that regulates arterial blood pressure. Despite their relevance to health and disease, not much is known about factors that confer and/or maintain JG cell identity. To identify genes uniquely expressed in JG cells, we used a cell culture model and RNA differential display. JG cells cultured for 2 days express renin and renin mRNA, but after 10 days in culture they no longer contain or release renin and renin mRNA is reduced 700-fold. We report one cDNA differentially expressed in the 2-day JG cell culture that detects a 2.6-kb mRNA expressed at higher levels in newborn than adult kidney. Screening a 2-day culture JG cell cDNA library yielded clones representing differentially spliced transcripts. These cDNAs encode one unique protein (Zis) containing zinc fingers and domains characteristic of splicing factors and RNA binding proteins. Northern blot analysis confirmed Zis mRNA expression in differentiated JG cells, and identified an additional unique 1.5-kb transcript. The Zis transcripts are developmentally regulated in kidney and a number of other organs. The features of the Zis protein and its organ distribution suggest a possible role in regulation of transcription and/or splicing, both important steps for controlling developmentally expressed genes. PMID- 9374837 TI - Localization of the ROMK protein on apical membranes of rat kidney nephron segments. AB - The ATP-sensitive, inwardly rectifying K+ channel, ROMK, has been suggested to be the low-conductance ATP-sensitive K+ channel identified in apical membranes of mammalian renal thick ascending limb (TAL) and cortical collecting duct (CCD). Mutations in the human ROMK gene (KIR 1.2) have been identified in kindreds with neonatal Bartter's syndrome. In the present study, we generated polyclonal antibodies raised against both a COOH-terminal (amino acids 252-391) ROMK-maltose binding protein (MBP) fusion protein and an NH2-terminal (amino acids 34-49) ROMK peptide. Affinity-purified anti-ROMK COOH-terminal antibody detected the 45-kDa ROMK protein in kidney tissues and HEK-293 cells transfected with ROMK1 cDNA. The antibody also recognized 85- to 90-kDa proteins in kidney tissue; these higher molecular weight proteins were abolished by immunoabsorption with ROMK-MBP fusion protein and were also detected on Western blots using anti-ROMK NH2-terminal antibody. Immunofluoresence studies using anti-ROMK COOH-terminal antibody showed intense apical staining along the loop of Henle and distal nephron; staining with preimmune and immunoabsorbed serum was negative. When colocalized with distal nephron markers [the thiazide-sensitive cotransporter (rTSC1), the bumetanide sensitive cotransporter (rBSC1), the vacuolar type H(+)-ATPase, and neuronal nitric oxide synthase (NOS I)], the ROMK protein was found primarily at the apical border of cells in the TAL, macula densa, distal convoluted tubule, and connecting tubule. Within the CCD, the ROMK protein was expressed in principal cells and was absent from intercalated cells. The tubule localization and polarity of ROMK staining are consistent with the distribution of ROMK mRNA and provide more support for ROMK being the low-conductance K+ secretory channel in the rat distal nephron. PMID- 9374838 TI - Localization of endothelin-converting enzyme-1 in human kidney. AB - The distribution of endothelin-converting enzyme-1 (ECE-1) mRNA and protein was investigated in human kidney excised because of renal tumors. ECE-1 immunoreactivity was detected by immunohistochemistry throughout the different areas of the kidney in the vascular and tubular structures. In the cortex, ECE-1 immunostaining was present in the endothelial surface of arcuate and interlobular arteries and in arterioles. Weak specific immunoreactivity was present over some proximal and distal tubules. Few endothelial glomerular cells contained ECE-1 protein. In the medulla, ECE-1 immunoreactivity was observed in the vasa recta bundles and capillaries. ECE-1 immunostaining was also detected in the outer and inner medullary collecting ducts and thin limbs of Henle's loops. Immunohistochemical detection of the von Willebrand factor on adjacent sections confirmed the endothelial nature of the vascular cells that exhibited ECE-1 immunostaining. The distribution patterns of ECE-1 mRNA, investigated by in situ hybridization, appeared similar to that obtained by immunohistochemistry in the cortical and medullary vasculature and in different portions of the nephron. Northern blot and densitometric analyses demonstrated that ECE-1 mRNA levels were quantitatively similar in both the renal cortex and medulla. These results demonstrate that vascular endothelial and tubular epithelial cells in the cortex and medulla of the human kidney synthesize ECE-1, which, in turn, may play an important role in regulating endothelin production in physiological and pathological conditions. PMID- 9374839 TI - Ureteric bud cells secrete multiple factors, including bFGF, which rescue renal progenitors from apoptosis. AB - Kidney development requires reciprocal interactions between the ureteric bud and the metanephrogenic mesenchyme. Whereas survival of mesenchyme and development of nephrons from mesenchymal cells depends on signals from the invading ureteric bud, growth of the ureteric bud depends on signals from the mesenchyme. This codependency makes it difficult to identify molecules expressed by the ureteric bud that regulate mesenchymal growth. To determine how the ureteric bud signals the mesenchyme, we previously isolated ureteric bud cell lines (UB cells). These cells secrete soluble factors which rescue the mesenchyme from apoptosis. We now report that four heparin binding factors mediate this growth activity. One of these is basic fibroblast growth factor (bFGF), which is synthesized by the ureteric bud when penetrating the mesenchyme. bFGF rescues three types of progenitors found in the mesenchyme: precursors of tubular epithelia, precursors of capillaries, and cells that regulate growth of the ureteric bud. These data suggest that the ureteric bud regulates the number of epithelia and vascular precursors that generate nephrons by secreting bFGF and other soluble factors. PMID- 9374840 TI - An Arg-Gly-Asp peptide stimulates constriction in rat afferent arteriole. AB - The potential role of integrins in the myogenic mechanism was studied in the rat afferent arteriole (AA) by fluorescence immunolocalization and microperfusion of isolated AA. Confocal fluorescence images were acquired from frozen sections of rat kidney after indirect immunostaining for various integrin beta- and alpha subunits. The beta 1-, beta 3-, alpha 3-, alpha 5-, and alpha V-integrins were found on the plasma membrane in smooth muscle of AA, providing the morphological basis for participation of integrins in mechanotransduction. With 1 mM nitro-L arginine methyl ester (L-NAME) in the luminal perfusate to inhibit endogenous nitric oxide (NO) production from AA, the hexapeptide GRGDSP (10(-7)-10(-3)M) induced immediate vasoconstriction. The constriction was dose dependent and specific or peptides with arginine-glycine-aspartic acid (RGD) motifs, commonly found on the binding sites of extracellular matrix to integrins. In controls, the hexapeptide GRGESP induced no constriction. GRGDSP, 1 mM, induced a 21.6 +/- 2.6% decrease (P < 0.05, n = 6) in lumen diameter for 30 s and an 18.3 +/- 4.1% increase (P < 0.05, n = 6) in smooth muscle intracellular calcium concentration for 18 s, as measured by the emission ratio of Fluo-3/Fura Red. Binding of exogenous RGD motifs with exposed integrins on AA smooth muscle therefore triggers calcium-dependent vasoconstriction. However, the dose response to RGD was not sensitive to the myogenic tone of the vessel, which suggests that the integrin-mediated vasoconstriction is different from myogenic constriction. PMID- 9374841 TI - Systemic and renal hemodynamic changes in the luteal phase of the menstrual cycle mimic early pregnancy. AB - Blood pressure decreases during early pregnancy in association with a decrease in peripheral vascular resistance and increases in renal plasma flow and glomerular filtration rate. These early changes suggest a potential association with corpora lutea function. To determine whether peripheral vasodilation occurs following ovulation, we studied 16 healthy women in the midfollicular and midluteal phases of the menstrual cycle. A significant decrease in mean arterial pressure in the midluteal phase of the cycle (midfollicular of 81.7 +/- 2.0 vs. midluteal of 75.4 +/- 2.3 mmHg, P < 0.005) was found in association with a decrease in systemic vascular resistance and an increase in cardiac output. Renal plasma flow and glomerular filtration rate increased. Plasma renin activity and aldosterone concentration increased significantly in the luteal phase accompanied by a decrease in atrial natriuretic peptide concentration. Serum sodium, chloride, and bicarbonate concentrations and osmolarity also declined significantly in the midluteal phase of the menstrual cycle. Urinary adenosine 3',5'-cyclic monophosphate (cAMP) excretion increased in the luteal compared with the follicular phase, whereas no changes in urinary cGMP or NO2/NO3 excretion were found. Thus peripheral vasodilation occurs in the luteal phase of the normal menstrual cycle in association with an increase in renal plasma flow and filtration. Activation of the renin-angiotensin-aldosterone axis is found in the luteal phase of the menstrual cycle. These changes are accompanied by an increase in urinary cAMP excretion indicating potential vasodilating mediators responsible for the observed hemodynamic changes. PMID- 9374842 TI - Effect of cyclosporin A on the expression of tissue kallikrein, kininogen, and bradykinin receptor in rat. AB - The tissue kallikrein-kinin system is involved in vasodilation and blood pressure regulation. In the present study, we investigated the effects of chronic cyclosporin A (CsA) administration on blood pressure and the expression of tissue kallikrein, kininogen, and bradykinin receptor in normotensive Wistar rats. Chronic administration of CsA significantly increased systolic blood pressure compared with control rats (n = 6, P < 0.01), although body weight was significantly lower than control rats (n = 6, P < 0.01). The development of hypertension was accompanied by the altered expression of kallikrein-kinin system components. Immunoreactive renal kallikrein and urinary excretion of tissue kallikrein levels were increased by chronic administration of CsA (n = 5 or 6, P < 0.05). Levels of N-tosyl-L-phenylalanine chloromethyl ketone-trypsin and kallikrein-releasable kininogens in sera increased in response to chronic CsA treatment (n = 5 or 6, P < 0.05). Chronic CsA treatment significantly increased renal kallikrein, bradykinin B2 receptor, and hepatic kininogen mRNA levels. The increased levels of tissue kallikrein-kinin system components were accompanied by significant increases in 24-h urine excretion and water intake after chronic CsA treatment (n = 5, P < 0.05). These results suggest that enhanced activity of the tissue kallikrein-kinin system may compensate for the CsA-induced vasoconstriction and hypertension. PMID- 9374843 TI - cDNA cloning and localization of OCRL-1 in rabbit kidney. AB - The oculocerebrorenal syndrome of Lowe (OCRL) is a hereditary multisystem disorder characterized by congenital cataract, mental retardation, renal tubular dysfunction, and progressive renal insufficiency. Tubular abnormalities include proximal tubular dysfunction, a distal acidification defect, and a possible impairment of urinary concentrating ability. The most important renal manifestation of Lowe's syndrome is a progressive loss of kidney function associated with a glomerular lesion that progresses to end-stage renal disease in either the third or fourth decade. The gene responsible for Lowe's syndrome, OCRL 1, was recently identified by positional cloning, and mutations were demonstrated in many affected patients. In the present study reverse transcription-polymerase chain reaction (RT-PCR) was used to clone a partial-length cDNA encoding rabbit renal OCRL-1. There is a high degree of similarity between rabbit and human sequences, with nucleotide and amino acid identities of 92% and 97%, respectively. Northern analysis identified a 5.4-kb transcript that is expressed in both rabbit kidney cortex and medulla. Isolated nephron-segment RT-PCR showed that OCRL-1 is expressed in all segments studied: the glomerulus, proximal tubule, medullary and cortical thick ascending limb, distal convoluted tubule, connecting tubule, cortical collecting duct, and outer medullary collecting duct. Defective OCRL-1 expression in these regions may play a pathogenetic role in the renal manifestations of this syndrome. PMID- 9374844 TI - Control of excretion of potassium: lessons from studies during prolonged total fasting in human subjects. AB - A deficit of K+ of close to 300 mmol develops in the first 2 wk of fasting, but little further excretion of K+ occurs, despite high levels of aldosterone and the delivery of ketoacid anions that are not reabsorbed in the distal nephron. Our purpose was to evaluate how aldosterone could have primarily NaCl-retaining, rather than kaliuretic, properties in this setting. To evaluate the role of distal delivery of Na+, four fasted subjects received an acute infusion of NaCl to induce a natriuresis. To assess the role of distal delivery of HCO3-, five fasted subjects were given an infusion containing NaHCO3. The natriuresis induced by an infusion of NaCl caused only a small rise in the rate of excretion of K+ (0.8 +/- 0.1 to 1.9 +/- 0.3 mmol/h); in contrast, when HCO3- replaced Cl- in the infusate, K+ excretion rose to 8.3 +/- 2.2 mmol/h, despite little excretion of HCO3- (urine, pH 5.8) and similar rates of excretion of Na+. The transtubular K+ concentration gradient was 19 +/- 3 with HCO3- and 6 +/- 2 with NaCl. We conclude that the infusion of NaHCO3 led to an increase in K+ excretion, likely reflecting an increased rate of distal K+ secretion. With a low distal delivery of HCO3-, aldosterone acts as a NaCl-retaining, rather than a kaliuretic, hormone. PMID- 9374846 TI - Effect of glandular kallikrein on distal nephron HCO3- secretion in rats and on HCO3- secretion in MDCK cells. AB - Renal kallikrein is localized in the connecting tubule cells and secreted into the tubular fluid at late distal nephron segments. The present experiments were performed to further test the hypothesis that renal kallikrein reduces bicarbonate secretion of cortical collecting duct (CCD). The effect of orthograde injections of pig pancreatic kallikrein (1 or 3 micrograms/ml) into the renal tubular system was investigated. Urine fractions (Fr) were collected after a 2 min stop flow. Changes in the urine fraction with respect to those in free-flow urine samples (Ff) were related to the respective polyfructosan (Inutest) ratio. Renal kallikrein activity (Fr:Ff kallikrein/ Fr:Ff polyfructosan) increased significantly in the first two urine fractions collected after glandular kallikrein administration (kallikrein, 1 microgram/ml, P < 0.05; kallikrein, 3 micrograms/ml, P < 0.01). HCO3- secretion of collecting ducts was significantly reduced dose dependently by orthograde and also reduced by retrograde pig pancreatic kallikrein administration. Release of kinins into the fractions was not affected by the retrograde kallikrein injection, even though the kallikrein activity increased considerably (2.26 +/- 0.2 vs. 1.55 +/- 0.2, P < 0.05). Adequacy of retrograde injections for delivering substances to the CCD was demonstrated by injecting colloidal mercury and detecting the appearance of this mercury in the renal cortex by transmission electron microscopy. The integrity of the renal tissue after a retrograde ureteral injection was confirmed by scanning electron microscopy. These results confirm and extend previous data (M. Marin Grez and P. Valles. Renal Physiol. Biochem. 17: 301-306, 1994; and M. Marin-Grez, P. Valles, and P. Odigie. J. Physiol. 488: 163-170, 1995) showing that renal kallikrein reduces bicarbonate secretion at the CCD, probably by inhibiting HCO3- transported by a mechanism unrelated to its kininogenase activity. Support for this assessment was obtained in experiments testing the effect of kallikrein on the luminal bicarbonate secretion of a subpopulation of Madin-Darby canine kidney cells capable of extruding the anion. Kallikrein inhibited HCO3-/Cl- exchange, and the degree of inhibition was dose dependent. This inhibition occurred in the absence of kininogen in the bathing solution. PMID- 9374845 TI - Identification of a new gene product (diphor-1) regulated by dietary phosphate. AB - Chronic restriction of dietary Pi elicits an increased reabsorption of Pi in the kidney proximal tubules, which involves a stimulation of apical Na-Pi cotransport. This adaptation is in part a direct cellular response of which the mechanism(s) are poorly understood. In this study, the impact of dietary Pi restriction on the differential expression of rat kidney cortex mRNAs was visualized to identify gene products regulated by the Pi status. When kidney cortex mRNAs of rats fed a low- or a high-Pi diet were compared by differential display-polymerase chain reaction (DD-PCR), thirty modulated cDNA bands were observed, of which four were confirmed as being regulated. We focused on one of the upregulated bands, dietary Pi-regulated RNA-1 (diphor-1). A cDNA containing an open reading frame encoding a 52-kDa protein was cloned by library screening. Diphor-1 exhibits a high degree of identity to the Na/H exchanger regulatory factor and to a tyrosine kinase activating protein. Highest expression of diphor 1 mRNA was detected in the kidney (proximal tubules) and in small intestine. Expression experiments showed that diphor-1 specifically increases Na-Pi cotransport in oocytes of Xenopus laevis coinjected with renal type II Na-Pi contransporter cRNA. Further characterizations of diphor-1 will show whether diphor-1 is primarily or secondarily involved in the response to dietary Pi. PMID- 9374847 TI - Determination of NH4+/NH3 fluxes across apical membrane of macula densa cells: a quantitative analysis. AB - Luminal addition of 20 mM NH4+ produced a rapid acidification of rabbit macula densa (MD) cells from 7.50 +/- 0.06 to 6.91 +/- 0.05 at an initial rate of 0.071 +/- 0.008 pH unit/s. In the luminal presence of 5 microM bumetanide, 5 mM Ba2+ or both, the acidification rate was reduced by 57%, 35% and 93% of control levels. In contrast, intracellular pH (pHi) recovery after removing luminal NH4+ was unaffected by bumetanide and Ba2+ but was sensitive to 1 mM luminal amiloride (71% inhibition). The bumetanide-sensitive acidification rate represents most certainly the NH4+ flux mediated by the apical Na+:K+ (NH4+):2Cl- cotransporter, but the Ba(2+)-sensitive portion does not seem to be associated with the apical K+ channels previously characterized by us. The effects of NH4+ entry across the apical membrane were simulated using a simple model involving five adjustable parameters: apical and basolateral permeabilities for NH4+ and NH3 and a parameter describing a pH-regulating mechanism. The model shows that the apical membrane of MD cells is much more permeable to NH3 than it is to NH4+ and, under control conditions, the apical NH4+ flux appears surprisingly high (11-20 mM/s) and challenges the notion that MD cells present a low intensity of ionic transport. PMID- 9374848 TI - Primary structure and functional expression of a cortical collecting duct Kir channel. AB - Maintenance of a negative membrane potential in the cortical collecting duct (CCD) principal cell depends on a small-conductance, inward-rectifying basolateral membrane K+ (Kir) channel. In the present study, a candidate cDNA encoding this K+ channel, CCD-IRK3, was isolated from a mouse collecting duct cell line, M1. CCD-IRK3 shares a high degree of homology with a human brain inward-rectifier K+ channel (Kir 2.3). By Northern analysis, CCD-IRK3 transcript (2.9 kb) was readily detected in M1 CCD cells but not in Madin-Darby canine kidney, LLC-PK1, Chinese hamster ovary, or monkey kidney fibroblast cell lines. CCD-IRK3-specific reverse transcription-polymerase chain reaction confirmed bonafide expression in the kidney. Functional expression studies in Xenopus oocytes revealed that CCD-IRK3 operates as strongly inward-rectifying K+ channel. The cation selectivity profile of CCD-IRK3 [ionic permeability values (PK/Pi), Tl > or = Rb > or = K+ >> NH4 > Na; inward-slope conductance (GK/Gi), Tl > or = K+ >> NH4 > Na > Rb] is similar to the macroscopic CCD basolateral membrane K+ conductance (GK/Gi, K+ >> NH4 > Rb; PK/Pi, Rb approximately equal to K+ >> NH4). CCD-IRK3 also exhibits the pharmacological features of the native channel. Patch clamp analysis reveals that CCD-IRK3 functions as a high open probability, voltage-independent, small-conductance channel (14.5 pS), consistent with the native channel. Based on these independent lines of evidence, CCD-IRK3 is a possible candidate for the small-conductance basolateral Kir channel in the CCD. PMID- 9374849 TI - Hypotonicity increases transcription, expression, and action of Egr-1 in murine renal medullary mIMCD3 cells. AB - In cells of the murine renal inner medullary collecting duct (mIMCD3) cell line, acute hypotonic shock (50% dilution of medium with sterile water but not with sterile 150 mM NaCl) increased Egr-1 mRNA abundance 2.5-fold at 6 h, as determined by Northern analysis. This increase was accompanied by increased Egr-1 transcription, as quantitated by luciferase reporter gene assay. Increased transcription was dose dependent, additive with other Egr-1 transcriptional activators, and occurred in the absence of overt cytotoxicity, as quantitated via a fluorometric viability assay. In addition, hypotonic stress increased Egr-1 protein abundance, which was accompanied by augmented Egr-1-specific DNA binding ability, as measured via electrophoretic mobility shift assay. Increased DNA binding was further associated with increased transactivation by Egr-1, demonstrated through transient transfection of mIMCD3 cells with a luciferase reporter gene driven by tandem repeats of the Egr-1 DNA consensus sequence. Taken together, these data indicate that hypotonic stress activates Egr-1 transcription, translation, DNA binding, and transactivation in renal medullary cells. This phenomenon might play a role in the acquisition of the adaptive phenotype in response to hypotonic stress in cells of the renal medulla in vivo. PMID- 9374850 TI - A functional CFTR-NBF1 is required for ROMK2-CFTR interaction. AB - In a previous study on inside-out patches of Xenopus oocytes, we demonstrated that the cystic fibrosis transmembrane conductance regulator (CFTR) enhances the glibenclamide sensitivity of a coexpressed inwardly rectifying K+ channel, ROMK2 (C. M. McNicholas, W. B. Guggino, E. M. Schwiebert, S. C. Hebert, G. Giebisch, and M. E. Egan. Proc. Natl. Acad. Sci. USA 93: 8083-8088, 1996). In the present study, we used the two-microelectrode voltage-clamp technique to measure whole cell K+ currents in Xenopus oocytes, and we further characterized the enhanced sensitivity of ROMK2 to glibenclamide by CFTR. Glibenclamide inhibited K+ currents by 56% in oocytes expressing both ROMK2 and CFTR but only 11% in oocytes expressing ROMK2 alone. To examine the role of the first nucleotide binding fold (NBF1) of CFTR in the ROMK2-CFTR interaction, we studied the glibenclamide sensitivity of ROMK2 when coexpressed with CFTR constructs containing mutations in or around the NBF1 domain. In oocytes coinjected with ROMK2 and a truncated construct of CFTR with an intact NBF1 (CFTR-K593X), glibenclamide inhibited K+ currents by 46%. However, in oocytes coinjected with ROMK2 and a CFTR mutant truncated immediately before NBF1 (CFTR-K370X), glibenclamide inhibited K+ currents by 12%. Also, oocytes expressing both ROMK2 and CFTR mutants with naturally occurring NBF1 point mutations, CFTR-G551D or CFTR-A455E, display glibenclamide-inhibitable K+ currents of only 14 and 25%, respectively. Because CFTR mutations that alter the NBF1 domain reduce the glibenclamide sensitivity of the coexpressed ROMK2 channel, we conclude that the NBF1 motif is necessary for the CFTR-ROMK2 interaction that confers sulfonylurea sensitivity. PMID- 9374851 TI - Single binding versus single channel recordings: a new approach to study ionotropic receptors. AB - The observation of ligand binding to a single molecule has become feasible with recent developments in laser-based fluorescence microscopy. We have simulated such single ligand-binding events for the nicotinic acetylcholine receptor in order to provide comparisons with single channel events under pulsed agonist conditions. The binding events would be more complex than ionic events due to multiple interconversions between different conformational states at the same degree of ligation. Nevertheless, recording of such events could provide valuable new information concerning the role of ligand binding in stabilizing conformational changes and the degree of functional nonequivalence of the binding sites. PMID- 9374852 TI - Four distinct cyclin-dependent kinases phosphorylate histone H1 at all of its growth-related phosphorylation sites. AB - In mammalian cells, up to six serines and threonines in histone H1 are phosphorylated in vivo in a cell cycle dependent manner that has long been linked with chromatin condensation. Growth-associated H1 kinases, now known as cyclin dependent kinases (CDKs), are thought to be the enzymes responsible for this process. This paper describes the phosphorylation of histone H1 by four different purified CDKs. The four CDKs phosphorylate only the cell cycle specific phosphorylation sites of H1, indicating that they belong to the kinase class responsible for growth-related H1 phosphorylation in vivo. All four CDKs phosphorylate all of the interphase and mitotic-specific H1 sites. In addition to the (S/T)PXK consensus phosphorylation sites, these four CDKs also phosphorylate a mitotic-specific in vivo H1 phosphorylation site that lacks this sequence. There is no site selectivity among the growth-related phosphorylation sites by any of the four CDKs because all four CDKs phosphorylate all relevant sites. The results imply that the cell cycle dependent H1 phosphorylations observed in vivo must involve differential accessibility of H1 sites at different stages of the cell cycle. PMID- 9374853 TI - Structural alignment of the (+)-trans-anti-benzo[a]pyrene-dG adduct positioned opposite dC at a DNA template-primer junction. AB - This study reports on the solution conformation of the covalent (+)-trans-anti [BP]dG adduct (derived from the binding of the highly mutagenic and tumorigenic (+)-anti-benzo[a]pyrene diol epoxide to the N2 of deoxyguanosine) positioned opposite dC at a junctional site in the d(A1-A2-C3-[BP]G4-C5- T6-A7-C8-C9-A10-T11 C12-C13).d(G14-G15-A16-T17-+ ++G18-G19-T20-A21-G22-C23) 13/10-mer DNA sequence. The 13-mer represents the template strand containing the junction [BP]dG4 lesion while the complementary 10-mer models a primer strand which extends upto and is complementary to the modified dG4 residue. The solution conformation has been determined by initially incorporating intramolecular and intermolecular proton proton distances defined by lower and upper bounds deduced from NOESY spectra as restraints in molecular mechanics computations in torsion angle space and subsequently through restrained molecular dynamics calculations based on a NOE distance and intensity refinement protocol. The duplex segment retains a minimally perturbed B-DNA conformation with all base pairs, including the junctional [BP]dG4.dC23 pair, in Watson-Crick hydrogen-bonded alignments. The pyrenyl ring is not stacked over the adjacent dC5.dG22 base pair but is positioned on the minor groove-side of the [BP]dG moiety and directed toward the 5'-end of the template strand. The pyrenyl ring stacks over the base of the non adjacent dA2 residue in one direction and the sugar ring of dC23 in the other direction. The solution structure of the (+)-trans-anti-[BP]dG adduct opposite dC in the 13/10-mer in which the modified deoxyguanosine adopts an anti glycosidic torsion angle (this study) is in striking contrast to the structure of the same (+)-trans-anti-[BP]dG moiety in a 13/9-mer of the same sequence but without the dC23 residue positioned opposite the adduct site [Cosman, M., et al. (1995) Biochemistry 34, 15334-15350]. For the latter case, the aromatic portion of the BP residue stacks over the adjacent dC5.dG22 base pair, the modified deoxyguanosine adopts a syn glycosidic torsion angle and is displaced toward the major groove direction. Insights into the factors that affect the sequence and context dependent conformations of stereoisomeric [BP]dG lesions have emerged following comparison of these two structures with the minor groove conformations of the same (+)-trans-anti-[BP]dG lesion in the fully complementary 11-mer duplex [Cosman, M., et al. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 1914-1918] and in the base displaced-intercalative conformation of the 11/10-mer deletion duplex containing a -1 deletion site opposite the lesion [Cosman, M., et al. (1994) Biochemistry 33, 11507-11517]. The contributing factors where applicable include Watson-Crick base pairing at the site of the lesion, positioning of the carcinogen within the floor of the minor groove, and the tendency of the bulky hydrophobic aromatic BP residue to assume stacked or intercalative conformations. PMID- 9374854 TI - Solution conformation of the (-)-trans-anti-[BP]dG adduct opposite a deletion site in a DNA duplex: intercalation of the covalently attached benzo[a]pyrene into the helix with base displacement of the modified deoxyguanosine into the minor groove. AB - A combined NMR-computational approach was employed to determine the solution structure of the (-)-trans-anti-[BP]dG adduct positioned opposite a -1 deletion site in the d(C1-C2-A3-T4-C5- [BP]G6-C7-T8-A9-C10-C11).d(G12-G13-T14-A15-G1 6-G17 A18-T19-G20-G21) sequence context. The (-)-trans-anti-[BP]dG moiety is derived from the binding of the (-)-anti-benzo[a]pyrene diol epoxide [(-)-anti-BPDE] to N2 of dG6 and has a 10R absolute configuration at the [BP]dG linkage site. The exchangeable and non-exchangeable protons of the benzo[a]pyrenyl moiety and the nucleic acid were assigned following analysis of two-dimensional NMR data sets in H2O and D2O solution. The solution conformation has been determined by incorporating intramolecular and intermolecular proton-proton distances defined by lower and upper bounds deduced from NOESY spectra as restraints in molecular mechanics computations in torsion angle space followed by restrained molecular dynamics calculations based on a NOE distance and intensity refinement protocol. Our structural studies establish that the aromatic BP ring system intercalates into the helix opposite the deletion site, while the modified deoxyguanosine residue is displaced into the minor groove with its face parallel to the helix axis. The intercalation site is wedge-shaped and the BP aromatic ring system stacks over intact flanking Watson-Crick dG.dC base pairs. The modified deoxyguanosine stacks over the minor groove face of the sugar ring of the 5' flanking dC5 residue. The BP moiety is positioned with the benzylic ring oriented toward the minor groove and the distal pyrenyl aromatic ring directed toward the major groove. This conformation strikingly contrasts with the corresponding structure in the full duplex with the same 10R (-)-trans-anti-[BP]dG lesion positioned opposite a complementary dC residue [de los Santos et al. (1992) Biochemistry 31, 5245-5252); in this case the aromatic BP ring system is located in the minor groove, and there is no disruption of the [BP]dG.dC Watson-Crick base pairing alignment. The intercalation-base displacement features of the 10R ( )-trans-anti-[BP]dG adduct opposite a deletion site have features in common to those of the 10S (+)-trans-anti-[BP]dG adduct opposite a deletion site previously reported by Cosman et al. [(1994)(Biochemistry 33, 11507-11517], except that there is a nearly 180 degrees rotation of the BP residue about the axis of the helix at the base-displaced intercalation site and the modified deoxyguanosine is positioned in the opposite groove. In the 10S adduct, the benzylic ring is in the major groove and the aromatic ring systems point toward the minor groove. This work extends the theme of opposite orientations of adducts derived from chiral pairs of (+)- and (-)-anti-BPDE enantiomers; both 10S and 10R adducts can be positioned with opposite orientations either in the minor groove or at base displaced intercalation sites, depending on the presence or absence of the partner dC base in the complementary strand. PMID- 9374855 TI - Backbone structure and dynamics of a hemolymph protein from the mealworm beetle Tenebrio molitor. AB - Pheromones play a vital role in the survival of insects and are used for chemical communication between members of the same species by their olfactory system. The selection and transportation of these lipophilic messengers by carrier proteins through the hydrophilic sensillum lymph in the antennae toward their membrane receptors remains the initial step for the signal transduction pathway. A moderately abundant 12.4 kDa hydrophilic protein present in hemolymph from the mealworm beetle Tenebrio molitor is approximately 38% identical to a family of insect pheromone-binding proteins. The backbone structure and dynamics of the 108 residue protein have been characterized using three-dimensional 1H-15N NMR spectroscopy, combined with 15N relaxation and 1H/D exchange measurements. The secondary structure, derived from characteristic patterns of dipolar connectivities between backbone protons, secondary chemical shifts, and homonuclear three-bond JHNH alpha coupling constants, consists of a predominantly disordered N-terminus from residues 1 to 10 and six alpha-helices connected by four 4-7 residue loops and one beta-hairpin structure. The up-and-down arrangement of alpha-helices is stabilized by two disulfide bonds and hydrophobic interactions between amphipathic helices. The backbone dynamics were characterized by the overall correlation time, order parameters, and effective correlation times for internal motions. Overall, a good correlation between secondary structure and backbone dynamics was found. The 15N relaxation parameters T1 and T2 and steady-state NOE values of the six alpha-helices could satisfactorily fit the Lipari-Szabo model. In agreement with their generalized order parameters (> 0.88), residues in helical regions exhibited restricted motions on a picosecond time scale. The stability of this highly helical protein was confirmed by thermal denaturation studies. PMID- 9374856 TI - Intramolecular assistance of cis/trans isomerization of the histidine-proline moiety. AB - Peptidyl-prolyl cis/trans isomerization is a slow conformational interconversion in the polypeptide backbone that is frequently rate-limiting in refolding of proteins and is thought to play a role in cellular restructuring of proteins. In order to probe the influence of positively charged amino acids located in sequence segments adjacent to proline, the rotational barriers of Arg-Pro- and His-Pro-containing peptides were determined by isomer-specific proteolysis and dynamic NMR spectroscopy for Suc-Ala-His-Pro-Phe-NH-Np, Ac-Ala-Arg-Pro-Ala-Lys NH2, Ac-Ala-His-Pro-Ala-Lys-NH2, angiotensin III, thyrotropin-releasing hormone (TRH), and [His(3-Me)2]TRH in aqueous solution. In contrast to the guanidinium group of arginine, the protonated side chain of histidine preceding proline led to an acceleration of the prolyl isomerization up to 10-fold relative to the unprotonated state. Both arginine and histidine residues succeeding proline in an amino acid sequence proved to be ineffective. Under basic and acidic conditions the kinetic solvent deuterium isotope effects Kc-->tH20/Kc-->tD20 for angiotensin III were 1.0 +/- 0.1 and 2.0 +/- 0.1, respectively. The results are interpreted in terms of intramolecular general acid catalysis of prolyl bond rotation by the imidazolium group that is without precedent in intermolecular catalysis. PMID- 9374857 TI - Isolation and characterization of nitric oxide reductase from Paracoccus halodenitrificans. AB - Nitric oxide reductase was isolated from the membrane fraction of a denitrifying bacterium, Paracoccus halodenitrificans, in the presence of n-dodecyl beta-D maltoside. A relatively simple and effective procedure to purify NO reductase using DEAE-Toyopearl and hydroxyapatite (ceramic) chromatographies has been developed. The enzyme consisted of two subunits with molecular masses of 20 and 42 kDa associated with the c-type heme and two b-type hemes, respectively. The optical and magnetic circular dichroism (MCD) spectra of the oxidized (as isolated) and reduced enzymes indicated that the heme c is in the low-spin state and the hemes b are in the high- and low-spin states. The EPR spectrum also showed the presence of the split high-spin component (g perpendicular = 6.6, 6.0) and two low spin components (gz,y,x = 2.96, 2.26, 1.46, gz = 3.59). Although the presence of an extra iron was suggested from atomic absorption spectroscopy, a non-heme iron could not be detected by colorimetric titrations using ferene and 2 (5-nitro-2-pyridylazo)- 5-(N-propyl-N-sulfopropylamino)phenolate (PAPS). One of the extra signals at g = 4.3 and 2.00 might come from a non-heme iron, while they may originate from an adventitious iron and a certain nonmetallic radical, respectively. When CO acted on the reduced enzyme, both of the low-spin hemes were not affected, and when NO acted on the reduced enzyme, the optical and MCD spectra were of a mixture of the oxidized and reduced enzymes. Consequently, the reduction of NO was supposed to take place at the high-spin heme b. The heme c and the low-spin heme b centers were considered to function as electron mediators during the intermolecular and intramolecular processes. PMID- 9374858 TI - Redox control of the catalytic cycle of flavocytochrome P-450 BM3. AB - Flavocytochrome P-450 BM3 from Bacillus megaterium is a 119 kDa polypeptide whose heme and diflavin domains are fused to produce a catalytically self-sufficient fatty acid monooxygenase. Redox potentiometry studies have been performed with intact flavocytochrome P-450 BM3 and with its component heme, diflavin, FAD, and FMN domains. Results indicate that electron flow occurs from the NADPH donor through FAD, then FMN and on to the heme center where fatty acid substrate is bound and monooxygenation occurs. Prevention of futile cycling of electrons is avoided through an increase in redox potential of more than 100 mV caused by binding of fatty acids to the active site of P-450. Redox potentials are little altered for the component domains with respect to their values in the larger constructs, providing further evidence for the discrete domain organization of this flavocytochrome. The reduction potentials of the 4-electron reduced diflavin domain and 2-electron reduced FAD domain are considerably lower than those for the blue FAD semiquinone species observed during reductive titrations of these enzymes and that of the physiological electron donor (NADPH), indicating that the FAD hydroquinone is thermodynamically unfavorable and does not accumulate under turnover conditions. In contrast, the FMN hydroquinone is thermodynamically more favorable than the semiquinone. PMID- 9374860 TI - Fluorescence spectroscopy of the longwave chlorophylls in trimeric and monomeric photosystem I core complexes from the cyanobacterium Spirulina platensis. AB - The organization and interaction of chlorophylls (Chl) and the kinetics of the energy transfer in the core antenna of photosystem I (PSI) trimeric and monomeric complexes, isolated from Spirulina platensis with Triton X-100 have been studied by stationary and time-resolved fluorescence. At 295 K both complexes show an unusually intense long-wavelength emission band with prominent peaks at 730 nm (trimers) or 715 nm (monomers), whose intensity is independent of the redox state of P700. A broad band extending from 710 to 740 nm in the absorption and fluorescence excitation spectra of trimers also indicates the existence of the longwave Chls at 295 K. The 77 K fluorescence emission of PSI trimers frozen after addition of dithionite under illumination (P700 and the PSI acceptor side reduced) shows an intense band at 760 (F760) and a smaller one at 725 nm (F725); when P700 is oxidized, the intensity of F760 decreases about 15 times. In the 77 K spectrum of monomers only F725 is present in the longwave region, and its intensity does not depend on the redox state of P700. Bands of Chls with maxima near 680, 710, and 738 nm were found in the 77 K excitation spectrum of trimers, and bands near 680 and 710 nm were seen in the spectrum of monomers. Five spectrally different red Chl forms in PSI trimers and three red Chl in monomers have been resolved by deconvolution of their 77 K absorption spectra. The difference absorption spectrum, trimers-minus-monomers, shows that the appearance of the 735 nm band in trimers is accompanied by a decrease of 708, 698, and 688 nm bands present in monomers. The reversible changes of F760 intensity of Spirulina membranes as a result of their salt treatment confirm the idea that the most longwave Chl form originates from an interaction of Chls bound to different monomeric PSI subunits forming the trimer. The time-resolved fluorescence spectra of PSI trimers and monomers, measured at 287 K in the region 680-770 nm, are substantially different, although a set of similar lifetimes (9, approximately 30, approximately 66, and 1400-2200 ps) was necessary for a good fit. No effect of P700 redox state was observed on the fluorescence kinetics of both complexes at 287 K. PMID- 9374859 TI - Glutamate 286 in cytochrome aa3 from Rhodobacter sphaeroides is involved in proton uptake during the reaction of the fully-reduced enzyme with dioxygen. AB - The reaction with dioxygen of solubilized fully-reduced wild-type and EQ(I-286) (exchange of glutamate 286 of subunit I for glutamine) mutant cytochrome c oxidase from Rhodobacter sphaeroides has been studied using the flow-flash technique in combination with optical absorption spectroscopy. Proton uptake was measured using a pH-indicator dye. In addition, internal electron-transfer reactions were studied in the absence of oxygen. Glutamate 286 is found in a proton pathway proposed to be used for pumped protons from the crystal structure of cytochrome c oxidase from Paracoccus denitrificans [Iwata et al. (1995) Nature 376, 660-669; E278 in P.d. numbering]. It is the residue closest to the oxygen binding binuclear center that is clearly a part of the pathway. The results show that the wild-type enzyme becomes fully oxidized in a few milliseconds at pH 7.4 and displays a biphasic proton uptake from the medium. In the EQ(I-286) mutant enzyme, electron transfer after formation of the peroxy intermediate is impaired, CuA remains reduced, and no protons are taken up from the medium. Thus, the results suggest that E(I-286) is necessary for proton uptake after formation of the peroxy intermediate and transfer of the fourth electron to the binuclear center. The results also indicate that the proton uptake associated with formation of the ferryl intermediate controls the electron transfer from CuA to heme a. PMID- 9374861 TI - Mechanism of Bacillus 1,3-1,4-beta-D-glucan 4-glucanohydrolases: kinetics and pH studies with 4-methylumbelliferyl beta-D-glucan oligosaccharides. AB - The carbohydrate binding site of Bacillus licheniformis 1,3-1,4-beta-D-glucan 4 glucanohydrolase was probed with a series of synthetic 4-methylumbelliferyl beta D-glucan oligosaccharides (1a-e). The title enzyme is a retaining endo glycosidase that has an extended carbohydrate binding site composed of four glucopyranosyl binding subunits on the non-reducing end from the scissile glycosidic bond, plus two or three subsites on the reducing end. Subsites -II to IV have a stabilizing effect on the enzyme-substrate transition state complex in the rate-determining step leading to a glycosyl-enzyme intermediate, with subsite -III having a larger effect (-3.5 kcal mol-1). Since KM values decrease from the mono- to the tetrasaccharide, part of the effect is due to ground stabilization of the Michaelis complex. On the other hand, the chromophoric trisaccharide 1c and the homologous nonchromogenic tetrasaccharide 2b, which locates a glucopyranosyl unit in subsite +I, have almost identical KM values, the difference in reactivity being a consequence of an 18-fold increase of kcat for 2b. Therefore, interactions between subsite +I and the substrate appear to be mainly used to lower the energy of the transition state in the glycosylation step, rather than in the stabilization of the Michaelis complex. Finally, the pH dependence of the kinetic parameters for the hydrolysis of 1c, and the pH dependent enzyme inactivation by a water-soluble carbodiimide (EAC) suggest two essential groups with pKa values of 5.5 and 7.0 in the free enzyme. The latter value is shifted up to 1.5 pH units upon binding of substrate in the non-covalent enzyme-substrate complex. PMID- 9374862 TI - The molecular basis of Celmer's rules: the stereochemistry of the condensation step in chain extension on the erythromycin polyketide synthase. AB - Modular polyketide synthases (PKSs), for example, the 6-deoxyerythronolide B synthase (DEBS) responsible for synthesis of the aglycone core of the macrolide antibiotic erythromycin, generate an impressive diversity of asymmetric centers in their polyketide products. However, as noted by Celmer, macrolides have the same absolute configuration at all comparable stereocenters. Understanding how the stereochemistry of chain extension in controlled is therefore crucial to determining the common mechanism of action of these enzymes. We aimed to elucidate the molecular basis of Celmer's rules through in vitro studies with DEBS 1-TE, a bimodular derivative of DEBS from Saccharopolyspora erythraea, which uses (2S)-methylmalonyl-coenzyme. A to produce both D- and L-methyl centers in its triketide lactone product. We show here that condensation of (2S) methylmalonyl-CoA in module 2 proceeds with decarboxylative inversion without cleavage of the C-H bond adjacent to the methyl group; in contrast, in module 1 the chain extension process involves loss of the hydrogen attached to C-2 of the methylmalonyl-CoA precursor. The production of the D-methyl center in module 2 without loss of hydrogen from the asymmetric center of the (2S)-methylmalonyl-CoA establishes that condensation takes place with inversion of configuration as in fatty acid biosynthesis. The loss of the key hydrogen from the (2S)-methylmalonyl CoA to produce the L-methyl center generated in module 1 implies that an additional obligatory epimerization step takes place in that module. The nature and timing of the epimerization remain to be established. PMID- 9374863 TI - Reaction of 2-methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) oxygenase with N methyl-5-hydroxynicotinic acid: studies on the mode of binding, and protonation status of the substrate. AB - Titrations of 2-methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) oxygenase with the substrate MHPC identified the MHPC species bound to the enzyme as the tripolar ionic species. This result was supported by studies of the binding to the enzyme of N-methyl-5-hydroxynicotinic acid (NMHN), an MHPC analog existing only in the tripolar ionic form. The Kd is 55 microM compared to a Kd of 9.2 microM for MHPC and 5.2 microM for 5-hydroxynicotinic acid. Kinetics studies of the binding of NMHN to MHPC oxygenase show that its binding, like that for MHPC and for 5HN, is also a two-step process. Since NMHN never exists as an anionic form, neither of the observed steps is due to the binding of an anionic species as an intermediate step. Investigations of the reduction and oxygenation half reactions demonstrate that the mechanism of catalysis with NMHN is basically the same as with MHPC or with 5-hydroxynicotinic acid. Product analysis from reactions using NMHN, a compound that possesses positive charge on the nitrogen atom, indicates that the product of NMHN is an aliphatic compound, similar to the products derived from MHPC and from another substrate analog, 5-hydroxynicotinic acid. These results indicate that the nitrogen atom of the substrate is invariably protonated during the catalytic reaction. PMID- 9374864 TI - Biochemical and physical parameters of the electrical currents measured with the ADP/ATP carrier by photolysis of caged ADP and ATP. AB - The transport by the mitochondrial ADP/ATP carrier (AAC) has been shown in a preliminary communication to produce electrical capacitive currents on photolysis of caged ATP or ADP with reconstituted AAC liposomes attached to black lipid membranes [Brustovetsky, N., Becker, A., Klingenberg, M., and Bamberg, E. (1996) Proc. Natl. Acad. Sci. U.S.A. 93, 664-668]. Here we study the relation of the currents to ADP/ATP fluxes, the interaction of caged ADP and ATP with AAC and other basic facets of this method. Caged ADP and ATP are not transported by the AAC, as shown in mitochondria. Flux measurements with reconstituted AAC show that caged nucleotides are competitive inhibitors (Ki = 5 microM for caged ADP and 1 microM for caged ATP). Caged ATP competes with photolyzed ATP as shown by the dependence of the currents on the caged ATP concentration and on the light intensity. A competition of added ADP with caged ATP on the currents yields Ki = 50 microM for ADP. We conclude that caged ADP and ATP bind tighter to AAC than ADP or ATP, allowing immediate initiation of translocation by in situ photolysis. The caged compounds bind preferentially at the cytosolic side of AAC. With a regenerative hexokinase + glucose system, the currents are stabilized in repetitive flashes and can be used for applying inhibitors etc. during a flash series. The currents are completely inhibited by the combined addition of the AAC inhibitors bongkrekate (BKA) and carboxyatractylate (CAT). The partial inhibition by CAT or BKA is dependent on the number of flash cycles increasing from 60% to 90%, and by replacing chloride with gluconate from only 30% to 90%. The current are increased by a K+ diffusion potential (valinomycin + KCl) and decreased by the permeant anion TPB-. The pH dependence of the currents and of the parallel flux measurements indicates that only the fully charged ATP4- and ADP3- are transported. A strong temperature dependence of the currents with a break at 15 degrees C (EA = 95 and 28 kJ) agrees with former measurements of flux rates in mitochondria. In conclusion, the capacitive currents faithfully reflect AAC transport function and are a powerful tool for investigating the charge transfer in transport. PMID- 9374865 TI - Structure-function relationships in helix-bundle channels probed via total chemical synthesis of alamethicin dimers: effects of a Gln7 to Asn7 mutation. AB - Alamethicin channels are prototypical helix bundles that may serve as tractable models for more complex protein ion channels. Solid-phase peptide synthesis of alamethicin analogues using FMOC-amino acid fluorides followed by chemical dimerization of these peptides facilitates structure-function studies of particular channel states in bilayer membranes. State 3 in particular, tentatively assigned to a hexameric helix bundle, is sufficiently long-lived that current-voltage measurements can be made during the lifetime of an individual channel opening. Molecular models of hexameric helix bundles, generated using restrained molecular dynamics with simulated annealing, indicate that a Gln7- >Asn7 (Q7-->N7) mutation will increase channel diameter locally. Experimentally, the conductance of state 3 of the N7-alm channel is found to be larger than that of the Q7-alm channel when ion flow is in the usual direction (cations entering the C-terminal end of the channel). When ion flow is in the opposite direction, no difference in the conductances of state 3 of Q7 and state 3 of N7 channels is observed. These results indicate that the effect of a change in pore diameter at position 7 is dependent on the magnitude of other barriers to permeation and that these barriers are voltage-dependent. PMID- 9374866 TI - Mapping the binding site for matrix metalloproteinase on the N-terminal domain of the tissue inhibitor of metalloproteinases-2 by NMR chemical shift perturbation. AB - Changes in the NMR chemical shift of backbone amide nuclei (1H and 15N) have been used to map the matrix metalloproteinase (MMP) binding site on the N-terminal domain of the tissue inhibitor of metalloproteinase-2 (N-TIMP-2). Amide chemical shift changes were measured on formation of a stable complex with the catalytic domain of stromelysin-1 (N-MMP-3). Residues with significantly shifted amide signals mapped specifically to a broad site covering one face of the molecule. This site (the MMP binding site) consists primarily of residues 1-11, 27-41, 68 73, 87-90, and 97-104. The site overlaps with the OB-fold binding site seen in other proteins that share the same five-stranded beta-barrel topology. Sequence conservation data and recent site-directed mutagenesis studies are discussed in relation to the MMP binding site identified in this work. PMID- 9374867 TI - Access to phosphorylation in isocitrate dehydrogenase may occur by domain shifting. AB - To clarify further the mechanism of regulation by phosphorylation of isocitrate dehydrogenase, cocrystallization of isocitrate dehydrogenase and isocitrate dehydrogenase kinase/phosphatase in the presence of an ATP analog was attempted. Although cocrystallization was unsuccessful, a new crystal form of isocitrate dehydrogenase was obtained which provides insight into the phosphorylation mechanism. The new, orthorhombic crystal form of isocitrate dehydrogenase is related to the previously reported tetragonal form largely by an approximately 16 degrees shift of a large domain relative to the small domain and clasp region within each subunit of the dimeric enzyme. The NADP+ cofactor binding surface is significantly disrupted by the shift to the open conformation. The solvent accessible surface area and surface-enclosed volume increase by 2% relative to the dimeric tetragonal form. Most of the increase results from expansion of the active site cleft such that the distance across its opening increases from approximately 5 to 13 A, significantly increasing accessibility to Ser-113. The conformation of isocitrate dehydrogenase in the orthorhombic crystal form more closely resembles that of the crystal structure of the homologous enzyme 3 isopropylmalate dehydrogenase than does the tetragonal isocitrate dehydrogenase conformation. Since the crystal lattice forces are fairly weak, it appears that isocitrate dehydrogenase is a flexible molecule that can easily undergo domain shifts and possibly other induced fit conformational changes, to accommodate binding to isocitrate dehydrogenase kinase/phosphatase. PMID- 9374868 TI - Comparison of two independent crystal structures of human dihydrofolate reductase ternary complexes reduced with nicotinamide adenine dinucleotide phosphate and the very tight-binding inhibitor PT523. AB - Structural data for two independent crystal forms (monoclinic, C2, and orthorhombic, P2(1)2(1)2(1)) of the ternary complex of the potent antitumor agent PT523 [N alpha-(4-amino-4-deoxypteroyl)-N delta-hemiphthaloyl-L-ornithine], reduced nicotinamide adenine dinucleotide phosphate (NADPH), and recombinant human dihydrofolate reductase (hDHFR) reveals multiple binding orientations for the hemiphthaloyl group of the inhibitor. Analysis of these data shows that PT523 binds with its pteridine ring in the same orientation observed for methotrexate (MTX) analogues. However, in each structure, the hemiphthaloyl ring occupies three alternate conformations. In the C2 lattice, the phthaloyl moiety binds in two extended conformations, A and C, with each conformer having a 180 degrees flip of the o-carboxylate group, and a third, lower occupancy conformer B, with the phthaloyl group folded within contact of the active-site pocket. In the orthorhombic lattice, PT523 also has three conformers for the phthaloyl group; however, these differ from those observed in the monoclinic lattice. Two major conformers, A and C, are displaced on either side of the extended position observed in the C2 lattice, one near the folded B conformer of the C2 lattice and the other extended. These conformers form tighter intermolecular contacts than those in the C2 lattice. Conformer B is folded back away from the active site in a unique position. There are also significant differences in the conformation of the adenine-ribose moiety of NADPH in both complexes that differ from that observed for other inhibitor-NADPH-hDHFR ternary complexes. These data suggest that the added intermolecular contacts made by the hemiphaloyl group of PT523 contribute to its tighter binding to hDHFR than MTX, which does not extend as far from the active site and cannot make these contacts. These crystallographic observations of multiple conformations for the hemiphthaloyl group are in general agreement with solution NMR data for the binding of PT523 to hDHFR [Johnson et al. (1997) Biochemistry 36, 4399-4411], which show that the hemiphthaloyl group may adopt more than one conformation. However, the crystallographic data reveal more discretely occupied positions than can be interpreted from the solution data. These results suggest that crystal packing interactions may influence their stability. PMID- 9374869 TI - Crystal structure of the Escherichia coli peptide deformylase. AB - Protein synthesis in bacteria involves the formylation and deformylation of the N terminal methionine. As eukaryotic organisms differ in their protein biosynthetic mechanisms, peptide deformylase, the bacterial enzyme responsible for deformylation, represents a potential target for antibiotic studies. Here we report the crystallization and 2.9 A X-ray structure solution of the zinc containing Escherichia coli peptide deformylase. While the primary sequence, tertiary structure, and use of coordinated cysteine suggest that E. coli deformylase belongs to a new subfamily of metalloproteases, the environment around the metal appears to have strong geometric similarity to the active sites of the thermolysin family. This suggests a possible similarity in their hydrolytic mechanisms. Another important issue is the origin of the enzyme's specificity for N-formylated over N-acetylated substrates. Based on the structure, the specificity appears to result from hydrogen-bonding interactions which orient the substrate for cleavage, and steric factors which physically limit the size of the N-terminal carbonyl group. PMID- 9374870 TI - Purification, characterization, and inhibition of peptide deformylase from Escherichia coli. AB - Peptide deformylase (EC 3.5.1.31) catalyzes the removal of a formyl group from the N-termini of nascent ribosome-synthesized polypeptides, an obligatory step during protein maturation in eubacteria. Since its discovery in crude Escherichia coli extracts 3 decades ago, the deformylase has resisted all attempts of purification or characterization due to its extraordinary lability. By placing the coding sequence (def gene) of Escherichia coli deformylase behind a bacteriophage T7 promoter, we have, however, been able to overexpress this deformylase in Escherichia coli. Overproduction has allowed the purification of > 50 mg of deformylase enzyme from each liter of cell culture. Purified deformylase is highly active toward N-formylated peptide substrates. A new, sensitive assay for the deformylase has been developed by measuring the amount of released formate using a formate dehydrogenase. This has allowed for the assessment of the catalytic properties of peptide deformylase using a series of synthetic N formylated peptides as substrates. The deformylase exhibits strong preference for an L-methionine or the isosteric norleucine at the N-terminus of a substrate and has broad specificity for the rest of the residues. Small divalent metal chelators strongly inhibit the E. coli deformylase. In particular, certain 1,2- and 1,3-dithiol compounds act as potent, time-dependent inhibitors of the peptide deformylase. PMID- 9374871 TI - Mechanism of proton entry into the cytoplasmic section of the proton-conducting channel of bacteriorhodopsin. AB - Bacteriorhodopsin is the light-driven proton-pumping protein of Halobacterium salinarum that extracts protons from the well-buffered cytoplasmic space within the time limits set by the photocycle turnover. The specific mechanism of the proton uptake by the cytoplasmic surface of the protein was investigated in this study by the laser-induced proton pulse technique. The purple membrane preparations were labeled by fluorescein at two residues (36 or 38) of the cytoplasmic surface of the protein, sites that are close to the orifice of the proton-conducting channel. The membranes were pulsed by protons discharged from photoexcited pyranine [Nachliel, E., Gutman, M., Kiryati, S., and Dencher, N.A. (1996) Proc. Nat Acad. Sci. U.S.A. 93, 10747-10752). The reaction of the discharged protons with the pyranine anion and the fluorescein was measured with sub-microsecond resolution. The experimental signals were reconstructed through numeric integration of differential rate equations which quantitated the rates of all proton transfer reactions between all reactants present in the system. The interaction of protons with the orifice of the cytoplasmic channel is enhanced by the exposed carboxylates of the protein. A cluster of three carboxylates acts as a strong proton attractor site while one carboxylate, identified as D36, acts as a mediator that delivers the proton to the channel. The combination of these reactions render the surface of the protein with properties of a proton collecting antenna. The size of the collecting area is less than that of the protein's surface. PMID- 9374872 TI - P-glycoprotein is a dimer in the kidney and brain capillary membranes: effect of cyclosporin A and SDZ-PSC 833. AB - Radiation-inactivation studies were performed in order to elucidate the oligomeric nature of P-glycoprotein (P-gp) expressed in brain capillaries and renal brush border membranes (BBMs). Irradiation of renal BBMs resulted in a dose dependent loss of P-gp, which corresponded to a target size (TS) of 255 and 211 kDa, as detected by Western blot and [125I]arylazidoprazosin labeling, respectively. Similar TSs were determined for P-gp expressed in brain capillaries. These TSs correspond to approximately twice the size (120 kDa) of deglycosylated P-gp. Furthermore, the estimated TS for P-gp was not significantly different when renal BBMs were incubated with SDZ-PSC 833 (PSC) prior and during exposure to ionizing radiation. To confirm these results, the size of P-gp was evaluated from its mobility on blue-native polyacrylamide gels followed by Western blot analysis. Using this method, an apparent molecular size of 334 and 264 kDa was determined for P-gp in brain capillaries and renal BBMs, respectively. This corresponds to approximately twice the size of the glycosylated monomeric subunit of P-gp in brain capillaries (162 kDa) or renal BBMs (140 kDa). P-gp expressed in renal BBMs isolated from rats which had been treated daily with cyclosporin A (CsA) or PSC also migrated as a 264 kDa protein. These results suggest that P-gp exists mainly as a dimer in normal tissues and that resistance modulators such as CsA and PSC do not alter its oligomeric state. PMID- 9374873 TI - Evidence by site-directed mutagenesis that arginine 203 of thermolysin and arginine 717 of neprilysin (neutral endopeptidase) play equivalent critical roles in substrate hydrolysis and inhibitor binding. AB - Neprilysin (neutral endopeptidase-24.11, EC 3.4.24.11) is a mammalian zinc endopeptidase involved in the degradation of biologically active peptides. Although no atomic structure is available for this enzyme, site-directed mutagenesis studies have shown that its active site resembles closely that of the bacterial zinc-endopeptidase, thermolysin (EC 3.4.24.27). One active site residue of thermolysin, Arg-203, is involved in inhibitor binding by forming hydrogen bonds with the carbonyl group of a residue in the P1 position and also participates in a hydrogen bond network involving Asp-170. Sequence alignment data shows that Arg-717 of neprilysin could play a similar role to Arg-203 of thermolysin. This was investigated by site-directed mutagenesis with Arg-203 of thermolysin and Arg-717 of neprilysin being replaced by methionine residues. This led, in both cases, to decreases in kcat/Km values, of 122-fold for neprilysin and 2300-fold for thermolysin, essentially due to changes in kcat. The Ki values of several inhibitors were also increased for the mutated enzymes. In addition, the replacement of Asp-170 of thermolysin by Ala residue resulted in a decrease in kcat/Km of 220-fold. The results, coupled with a molecular modeling study, suggest that Arg-717 of neprilysin corresponds to Arg-203 of thermolysin and that in both enzymes a hydrogen bond network exists, involving His-142, Asp-170, and Arg-203 in thermolysin and His-583, Asp-650, and Arg-717 in neprilysin, which is crucial for hydrolytic activity. PMID- 9374874 TI - Reactions of [14C]-3,4-dichloroisocoumarin with subunits of pituitary and spleen multicatalytic proteinase complexes (proteasomes). AB - Exposure to [14C]-3,4-dichloroisocoumarin (DCI) of multicatalytic proteinase complexes (MPC) isolated from bovine pituitary and spleen leads to label incorporation into several beta-type subunits, to rapid inactivation of the chymotrypsin-like (ChT-L) activity, and to a slower inactivation of other activities of the MPC. The pituitary and spleen MPCs differ in that the first contains almost exclusively the X, Y, and Z subunits, whereas in the latter these subunits are largely replaced by LMP2, LMP7, and MECL1. Preincubation with two peptidyl aledhyde inhibitors of the ChT-L activity protected the X subunit in the pituitary MPC and unexpectedly the LMP2 subunit in the spleen MPC from label incorporation, despite the greater amino acid sequence homology of the LMP7 subunit to that of the X subunit. Losses in the yield of amino acids in both subunits, shown by amino acid sequencing, and lability of the DCI-protein bond indicated formation of an acyl derivative by reaction of DCI with the threonine OH group. Brief exposure to [14C]-DCI led to preferential incorporation of label into the LMP2 and X subunits, consistent with the high inactivation rate constants of the ChT-L activity. Z-LLF-CHO, an inhibitor of ChT-L activity, but not Z-GPFL-CHO, an inhibitor of the branched chain amino acid preferring component, prevented incorporation of radioactivity into the X subunits, whereas both inhibitors prevented label incorporation into LMP2, indicating differences in susceptibility to inhibition between the two components. These and other data are consistent with involvement of the X and LMP2 subunits in expression of the ChT-L activity in the pituitary and spleen MPC, respectively, and suggest the catalytic functions of two other beta-subunits. PMID- 9374875 TI - Inhibition of T7 RNA polymerase: transcription initiation and transition from initiation to elongation are inhibited by T7 lysozyme via a ternary complex with RNA polymerase and promoter DNA. AB - The mechanism of transcription repression of T7 RNA polymerase by T7 lysozyme was investigated using a combination of kinetic and equilibrium methods. HPLC gel filtration experiments demonstrated complex formation between T7 lysozyme, T7 RNA polymerase, and promoter DNA. The interactions between the two proteins were quantitated by measuring in real time the changes in protein fluorescence upon binary complex formation using stopped-flow kinetics. Complex formation between T7 lysozyme and the RNA polymerase was found to occur by a one-step process, with a bimolecular association rate constant of 38 microM-1 S-1 and a dissociation rate constant of 3.5 S-1. These constants provided an equilibrium dissociation constant, Kd, of 92 nM for the polymerase lysozyme complex. The interactions of the polymerase with the DNA were studied by stopped-flow kinetics and nitrocellulose equilibrium DNA binding experiments in the absence and in the presence of T7 lysozyme. The results showed that T7 lysozyme did not prevent or change the kinetic or thermodynamic interactions of the RNA polymerase with the DNA. T7 lysozyme by itself did not bind to the DNA, but since it bound to the RNA polymerase as well as to the polymerase DNA complex, transcription repression must involve the formation of the ternary complex between T7 lysozyme, T7 RNA polymerase and the promoter DNA. The effect of T7 lysozyme was most striking on runoff product synthesis which was greatly inhibited whereas the steady-state synthesis of abortive products, limited by polymerase cycling or RNA dissociation, was relatively unaffected by the presence of T7 lysozyme. Investigation of the pre-steady-state kinetics of transcription in the presence and absence of T7 lysozyme indicated that the inhibition of runoff product synthesis was largely due to inhibition of transcription initiation and transition from initiation to elongation. PMID- 9374877 TI - Why some cases of retinopathy worsen when diabetic control improves. PMID- 9374876 TI - Alanine mutagenesis of surfactant protein A reveals that lipid binding and pH dependent liposome aggregation are mediated by the carbohydrate recognition domain. AB - The carbohydrate recognition domain (CRD) of surfactant protein A (SP-A) is critical for the modulation of surfactant secretion from isolated type II cells and for the Ca(2+)-dependent aggregation of surfactant liposomes, but the domains of SP-A that mediate lipid binding have not been precisely mapped. To determine the role of the CRD in lipid interactions and other functions, the conserved amino acids of the putative Ca2+ and carbohydrate binding site (Glu195, Glu202, Asn214, Asp215) were substituted with alanine. The wild-type recombinant protein, SP-Ahyp, and mutant SP-As SP-Ahyp,E195A, SP-Ahyp,E202A, SP-Ahyp,N214A, and SP Ahyp,D215A, were expressed in insect cells using baculovirus vectors and compared functionally. The Ca(2+)-dependent binding and aggregation of liposomes at pH 7.0 by SP-Ahyp,N214A were comparable to SP-Ahyp, but these activities were blocked in SP-Ahyp,E195A, SP-Ahyp,E202A, and SP-Ahyp,D215A. In contrast, the SP-Ahyp,D215A but not the other mutant proteins induced the Ca(2+)-independent aggregation of phospholipid liposomes at pH 4.0. The mutant recombinant proteins did not compete with 125I-labeled rat SP-A for high-affinity receptor occupancy on isolated type II cells and were much less potent than SP-Ahyp as regulators of surfactant secretion and uptake from type II cells. We conclude that (1) lipid binding and pH-dependent liposome aggregation are mediated by the CRD of SP-A, (2) distinct but overlapping domains within the CRD are required for pH- and Ca(2+)-dependent liposome aggregation, and (3) conserved acidic and polar residues of the carbohydrate binding site of SP-A are essential for interactions with type II cells. PMID- 9374878 TI - Changing incidence and mortality from cutaneous malignant melanoma. PMID- 9374879 TI - Acute excited states and sudden death. PMID- 9374880 TI - Teaching medical students in general practice: respecting patients' rights. PMID- 9374881 TI - Medicine based evidence, a prerequisite for evidence based medicine. PMID- 9374882 TI - Fetuses cannot feel pain before 26 weeks. PMID- 9374883 TI - Cutaneous malignant melanoma in Scotland: incidence, survival, and mortality, 1979-94. The Scottish Melanoma Group. AB - OBJECTIVE: To determine the changing incidence of and mortality from cutaneous malignant melanoma in Scotland from 1979 to 1994. DESIGN: Detailed registration of clinical and pathological features, surgical and other treatment, and follow up of all cases of cutaneous malignant melanoma diagnosed from 1979 to 1994 and registered with specialist database for Scotland. SETTING: Scotland. SUBJECTS: 6288 patients with invasive primary cutaneous malignant melanoma diagnosed between 1 January 1979 and 31 December 1994. RESULTS: The annual age standardised incidence of cutaneous malignant melanoma rose significantly from 3.5 to 7.8 per 100,000 per year in men and from 6.8 to 12.3 per 100,000 per year in women (P < 0.001 for both). World standardised rates increased from 2.7 to 6.0 per 100,000 per year in men and 4.6 to 8.50 per 100,000 in women. The incidence of melanoma continued to increase significantly in men of all ages during the study, but the rate stabilised in women after 1986. Mortality from cutaneous malignant melanoma was 1.3 per million per annum in men in 1979, rising to 2.3 per million per annum in 1994 (P < 0.01); it was 2.4 per million per annum in women in 1979, falling to 1.9 per million per annum in 1994 (P = 0.09). The underlying mortality trends showed a continuing rise for men but a downward trend for women that was not significant (P = 0.09). In men, melanoma free survival was 69% at 5 years and 61% at 10 years; in women the corresponding rates were 82% and 75%. Younger patients had higher survival rates, which were not entirely explained by thinner tumours. Over the 15 year period, survival rates improved by 12% overall, only partly owing to thinner tumours. CONCLUSIONS: In Scotland the incidence of melanoma in women has stabilised, while mortality associated with melanoma in women shows a downward trend. PMID- 9374885 TI - Impact of the NHS reforms on English hospital productivity: an analysis of the first three years. AB - OBJECTIVES: To evaluate the effect of purchaser mix, market competition, and trust status on hospital productivity within the NHS internal market. METHODS: Hospital cost and activity data were taken from routinely collected data for acute NHS hospitals in England for 1991-2 to 1993-4. Cross sectional and longitudinal regression methods were used to estimate the effect of trust status, competition, and purchaser mix on average hospital costs per inpatient, after adjusting for outpatient activity levels, casemix, teaching activity, regional salary variation, hospital size, scale of activity, and scope of cases treated. RESULTS: Real productivity gains were apparent across the study period for NHS hospitals on average. Casemix adjustment drastically improved cross sectional comparisons between hospitals. Gaining trust status and increasing host district purchaser share were associated with productivity increases after adjustment for casemix, regional salary differences, and hospital size and scope. Hospitals that became trusts during the study period were on average less productive at the beginning of the period than those that did not, and there were no significant productivity differences between trust waves at the end of the period in 1993-4. Market concentration was not associated with productivity differences. CONCLUSION: Further analysis is needed to determine whether overall and trust associated productivity gains are transient effects, one off shifts, or self perpetuating reorientations of organisational behaviour. Hospitals may have chosen to become trusts because they anticipated being able to increase productivity. Increases in the proportions of small purchasers were associated with increasing costs. Importantly, this study could not adjust for changes in the quality of care. PMID- 9374886 TI - Inequalities in income and long-term disability in Spain: analysis of recent hypotheses using cross sectional study based on individual data. AB - OBJECTIVE: To compare the relation between inequalities in long-term disability and income in the 17 regions of Spain. DESIGN: Data were taken from the survey on impairments, disabilities, and handicaps that was carried out in Spain in 1986. For each region the inequality in long-term disability associated with income was calculated as the odds ratio associated with reducing monthly household income by 10,000 pesetas (about Ponds 50) (estimate of effect of inequality of income) and the odds ratio for the inequality in long-term disability between those at the bottom and those at the top of the income hierarchy (relative index of inequality). MAIN OUTCOME MEASURE: Prevalence of long-term disability. RESULTS: Five of the eight regions where lowering income had a greater effect on long-term disability were among those with the lowest income per head, while six of the remaining nine regions where the effect was smaller were among those with the highest income per head. Three regions with the highest estimate of relative index of inequality had the highest estimate of effect, and another three regions with the lowest estimate of relative index of inequality had the lowest estimate of effect. In contrast, the relative position of the remaining 11 regions varied from one measure to another. CONCLUSIONS: These results support the theory that additional increments in material wellbeing have a negligible effect on health in countries with high socioeconomic development. However, inequality in income distribution did not determine inequality in health between those at the bottom and those at the top of the income hierarchy in many Spanish regions. PMID- 9374884 TI - Effect of nutrition improvement project on morbidity from infectious diseases in preschool children in Vietnam: comparison with control commune. AB - OBJECTIVE: To evaluate the effect of a nutrition improvement project based on home garden production and nutrition education on morbidity from acute respiratory infection and diarrhoeal disease in preschool children. DESIGN: The morbidity survey comprised five data collections undertaken by trained interviewers to ascertain the incidence and severity of respiratory infections and the incidence of diarrhoeal disease in children in two communes. SETTING: A project commune and a control commune in Vietnam. SUBJECTS: Preschool children to 6 years of age living in the project commune Khai Xuan (average 469 children) and the control commune Ching Cong (average 251 children). MAIN OUTCOME MEASURES: Differences between the two communes over time in the incidence and severity of respiratory infections and the incidence of diarrhoeal disease. RESULTS: In Khai Xuan there was a significant reduction (P < 0.0001) in the incidence of respiratory infections (from 49.5% to 11.2%) and diarrhoeal infections (18.3% to 5.1%); the incidence of pneumonia and severe pneumonia was also significantly reduced (P < 0.0001). In Ching Cong there was no significant change in the incidence and severity of respiratory disease nor in the incidence of diarrhoeal disease. CONCLUSIONS: These findings emphasise the successful health outcome of a nutrition project based on household food production and nutrition education and the value of evaluating nutrition projects by reference to measurable health outcomes. PMID- 9374887 TI - Improving response rates among doctors: randomised trial. PMID- 9374888 TI - Relation between weight and length at birth and body mass index in young adulthood: cohort study. PMID- 9374889 TI - Patients' views on their discharge from follow up in outpatient clinics: qualitative study. AB - OBJECTIVES: To discover the views of patients about their discharge from outpatient clinics, to detect any change in these perceptions over time, and explore how the discharge process might be improved for the patient. DESIGN: A qualitative study comprising in-depth or semistructured interviews with patients 2 weeks and 3 months after discharge from an outpatient clinic. SUBJECTS: 45 patients who had attended outpatient clinics on three or more occasions. SETTING: Five general medical outpatient clinics from a Manchester provider trust. MAIN OUTCOME MEASURES: Aspects of the discharge consultation valued by patients included confidence that the doctor knew and understood their case; clarity of the discharge process; an explanation of the reasons for discharge; information about treatment, future care, and the mechanism for re-referral; and being seen by doctors who sought their views and allowed time for questions and reflection. CONCLUSIONS: Patients' views about their discharge changed over time and varied in relation to several factors, which included patients' perceptions of the discharge process, patients' expectations, the way in which the outpatient clinics were organised, and patients' relationships with, and confidence in, their general practitioners. PMID- 9374891 TI - Fortnightly review. A regular review of the long-term follow up of depression. PMID- 9374890 TI - Consent and confidentiality in teaching in general practice: survey of patients' views on presence of students. PMID- 9374892 TI - Delayed closure of injuries to the hand caused by blasts helps to preserve function. PMID- 9374893 TI - ABC of palliative care. Nausea, vomiting, and intestinal obstruction. PMID- 9374894 TI - Confounding and indication for treatment in evaluation of drug treatment for hypertension. PMID- 9374895 TI - Women's health is a global issue. PMID- 9374896 TI - Influence of cholesterol on survival after stroke. Beneficial effects of cholesterol lowering on atherosclerosis may not lessen with age. PMID- 9374897 TI - Influence of cholesterol on survival after stroke. Regression to the mean may have been a factor. PMID- 9374898 TI - Influence of cholesterol on survival after stroke. Cholesterol may be marker of inflammation. PMID- 9374899 TI - Influence of cholesterol on survival after stroke. Effect of cholesterol on prognosis may rely on negative association with atrial fibrillation. PMID- 9374900 TI - Gonorrhoea and ethnicity. Audit supports findings. PMID- 9374901 TI - Gonorrhoea and ethnicity. Collaborative surveillance system is a model for the future. PMID- 9374902 TI - Improving ethnic data within surveillance must be priority. PMID- 9374903 TI - Funding of drug treatment of multiple sclerosis should not be delayed. PMID- 9374904 TI - Heterogeneity of air pollution effects is related to average temperature. PMID- 9374905 TI - Mental health assessment. Open and closed questions are often confused. PMID- 9374906 TI - Aciclovir in herpes simplex gingivostomatitis. Children studied were not representative of those seen in casualty departments. PMID- 9374907 TI - Aciclovir in herpes simplex gingivostomatitis. Folic acid may be beneficial in aphthous stomatitis. PMID- 9374908 TI - Tobacco manufacturers did not orchestrate media interest in possible ban on tobacco sponsorship. PMID- 9374909 TI - Approval of SHO posts is rarely withdrawn but is often given for limited time. PMID- 9374910 TI - Steroids should never be given until possible herpes zoster infection has been excluded. PMID- 9374911 TI - Marfan's syndrome might have been factor in acute dissection of aorta in amphetamine misuser. PMID- 9374912 TI - Future of international health. WHO is taking proactive role in advancing policy of health for all. PMID- 9374913 TI - Future of international health. WHO, governments, and non-government organisations must work together. PMID- 9374914 TI - End of life decisions. Good care aims at ending patients' suffering, not their life. PMID- 9374915 TI - End of life decisions. Future of vulnerable people is threatened by euthanasia. End of life decisions. PMID- 9374916 TI - Many people who disapprove of abortion nevertheless think it should be legal. PMID- 9374917 TI - Corticosteroid-induced osteoporosis: guidelines for prevention--are they useful? PMID- 9374918 TI - Autoantigen components recognizable by scleroderma sera are exported via ectocytosis of fibroblasts. AB - Previously, we have demonstrated that ectocytosis, a unique cell trafficking process to export a specific subset of cellular proteins in the form of membrane vesicles, can be triggered from human skin fibroblasts cultured in a three dimensional collagen lattice upon stress relaxation. The same culturing system was employed in the present study using fibroblasts isolated from patients with systemic sclerosis (SSc). To see whether any putative intracellular autoantigens causing SSc might escape out of cells by way of ectocytosis, the same stress relaxation method was used to induce a synchronized ectocytosis among cultured cells. Membrane vesicles released by scleroderma fibroblasts were subsequently isolated, resolved on SDS-PAGE and immunoblotted with sera from 89 patients with various autoimmune diseases and 11 normal volunteers. Three major polypeptides with apparent mol. wts of 12-14, 32-34 and 70-80 kDa are prominent bands on both SDS-PAGE and immunoblots. The 32-34 kDa polypeptide has been further identified as a member of the annexin protein family, while the 70-80 kDa protein has been shown to be topoisomerase I, as judged by its reactivity to patients' sera and a rabbit polyclonal antibody, and as also judged by a functional assay. In conclusion, our results suggest that ectocytosis might be one of the potential pathways for cells to export intracellular antigens and subsequently cause autoimmune reactions. PMID- 9374919 TI - The coagulation/fibrinolysis balance in systemic sclerosis: evidence for a haematological stress syndrome. AB - Systemic sclerosis (SSc) is a disease characterized by progressive microvascular occlusion and fibrosis resulting in irreversible organ damage, the pathogenesis of which is felt to be of vascular origin. To gain a comprehensive view of the coagulation/fibrinolytic balance in SSc, a number of haemostatic and fibrinolytic variables were measured in 26 SSc patients (11 limited, 15 diffuse) and in 22 control subjects. Of the coagulation activation markers, the mean plasma level of prothrombin fragment 1 + 2 (F1 + 2), but not of thrombin-antithrombin complexes (TAT), was higher in SSc patients than in controls (P < 0.001). Plasma levels of fibrin split product D-dimer (DD), fibrinogen (FNG) and von Willebrand factor (vWF) were higher amongst patients than controls (P < 0.001). vWF and FNG levels were positively correlated (P < 0.001). Mean levels of DD and vWF were more elevated in patients with diffuse than limited disease (P = 0.001 and P = 0.04, respectively). On the fibrinolytic side, defective tissue plasminogen activator (tPA) release (venous occlusion test, stimulated level < basal level) was noted in 46% (12/26) of SSc patients, but only in 4% (1/22) of controls. Patients had higher mean levels of tPA inhibitor (PAI) than controls (P < 0.001), levels being more elevated amongst patients with diffuse than limited disease (P = 0.01). An abnormally high lipoprotein (a) [Lp(a)] level was found in 9% (2/20) of control subjects, but in 30% (8/26) of SSc patients (P = 0.04) where it clustered with fibrinolytic defects. Altogether, these data suggest that patients with SSc are in a hypercoagulable state characterized by elevated plasma levels of FNG and vWF, by a dual hypofibrinolytic pattern (defective tPA release and elevated PAI), and by increased thrombin generation with enhanced fibrin formation. Higher levels of vWF, DD and PAI in patients with diffuse disease are consistent with more extensive (micro)vascular involvement, although no causal relationship can be inferred. The lack of a parallel increase of TAT with F1 + 2, in the presence of normal levels of antithrombin III (ATIII), indirectly suggests an impairment of the heparan sulphate-ATIII system which would favour thrombin generation. Since thrombin may act as a mitogen for fibroblasts, may upregulate vWF, PAI and endothelin production by endothelial cells, and may promote fibrin deposition on the vessel wall leading to worsening of microvascular occlusions, limitation of thrombin generation, besides fibrinolytic enhancement, could represent a possible coadjuvant interventional strategy. PMID- 9374920 TI - IgM, IgG and IgA class enterobacterial antibodies in serum and synovial fluid in patients with ankylosing spondylitis and rheumatoid arthritis. AB - IgM, IgG and IgA class antibodies against three Klebsiella pneumoniae capsular types, Escherichia coli and Proteus mirabilis, as well as total immunoglobulin concentrations, were measured by enzyme immunoassay and radial immunodiffusion technique, respectively, in paired serum and synovial fluid samples from eight patients with ankylosing spondylitis and 10 with rheumatoid arthritis. No clear evidence for intra-articular antibody production against any of the studied microbes was found. PMID- 9374921 TI - Nickel contamination of gold salts: link with gold-induced skin rash. AB - Intramuscular chrysotherapy is a well-established treatment for rheumatoid arthritis. Its therapeutic use has been limited by the high incidence of dermatological side-effects. The pathogenic mechanisms of these are unknown, but could include allergic reactions to gold or to nickel contaminating the gold. In order to investigate these mechanisms further, 15 patients, who developed cutaneous eruptions after chrysotherapy, were assessed using skin biopsy and lymphocyte transformation stimulated by gold and nickel salts in vitro. Chrysotherapy induced two main cutaneous eruptions: lichenoid reactions and non specific dermatitis. Peripheral blood mononuclear cells from patients with lichenoid reaction proliferated to gold salts in vitro, while those who developed non-specific dermatitis responded mainly to nickel. Nickel was a significant contaminant of the gold preparation (sodium aurothiomalate, Myocrisin, Rhone Poulenc Ltd), amounting to a total of 650 ng after 6 months treatment. We suggest that a significant percentage of skin reactions during chrysotherapy are due to nickel contamination of the gold preparation. PMID- 9374922 TI - Necrotizing vasculitis in Greece: clinical, immunological and immunogenetic aspects. A study of 66 patients. AB - The clinical spectrum and outcome of necrotizing vasculitis were evaluated in a retrospective study in order to assess: (1) the clinical expression and evolution of the disease; (2) the response to several therapeutic approaches based on major events (organ involvement causing disability or death); (3) the immunogenetic background of patients. Sixty-six Greek patients fulfilling the ACR criteria for the diagnosis of vasculitis entered the study. Thirty-seven were diagnosed with Wegener's granulomatosis (WG), 22 with polyarteritis nodosa (PAN) and seven with Churg-Strauss syndrome (CSS). The demographic characteristics of patients with WG and PAN were similar. Cutaneous manifestations, gastrointestinal and peripheral nervous system involvement occurred more often in patients with PAN, whereas pulmonary and upper respiratory tract involvement, renal, ear abnormalities and fever were more frequent in patients with WG. Muscle weakness and asthma were found exclusively in patients with PAN and CSS, respectively, while the presence of classic-antineutrophil cytoplasmic antibodies (c-ANCA) characterized WG patients. Hepatitis B surface antigen (HBsAg) was found in 22% of PAN patients. No significant differences were detected when comparing the PAN and WG groups with respect to the first major event (log-rank P = 0.50) with and without potential confounders (age, gender, therapy or c-ANCA). For WG patients, a statistically significant difference was found on different routes of administration of cyclophosphamide (oral vs pulse) (P = 0.006). Regarding the HLA antigens, an increased frequency of DR1 (26.9% vs 10.3%, P = 0.057) in WG and the absence of DR3 in patients with PAN and CSS were noted. It appears that although the immunogenetic background and the clinical expression of the diseases differ, the response to treatment as well as the evolution and the survival rate of these patients are similar in the two groups. PMID- 9374923 TI - Clinical features of lupus myositis versus idiopathic myositis: a review of 30 cases. AB - Myositis is a rare but well-recognized complication of systemic lupus erythematosus (SLE). It is reputed to be milder than primary myositis in terms of morbidity and treatment response. This study compares clinical and laboratory features of idiopathic inflammatory myositis in patients with and without evidence of SLE overlap. We performed a case note review of 30 patients with probable or definite polymyositis/dermatomyositis of whom 11 also had definite or probable SLE. Lupus patients were slightly younger at diagnosis than those with primary disease, and more likely to be female. At presentation, quadriceps strength (expressed as a percentage of expected) was significantly reduced in both the lupus (48.9%; 95% CI 29.0-70.4%) and primary (52.0%; 95% CI 43.6-59.4%) myositis groups, and serum creatine phosphokinase (expressed as a multiple of the upper limit of normal) was significantly elevated (11.2; 95% CI 5.3-29.1 vs 10.7; 95% CI 6.1-17.6). During a mean (S.D.) follow-up period of 7.4 (4.1) yr, both groups tended to follow either a relapsing and remitting, or a chronic persistent course, and when last seen quadriceps muscle strength remained significantly depressed. One of the lupus patients and two of the primary myositis patients died due to direct complications of the disease, and one further death was attributable to a complication of therapy. Our results suggest that lupus myositis is often as severe as primary disease and should be treated with equal vigour. PMID- 9374924 TI - Effects of detraining subsequent to strength training on neuromuscular function in patients with inflammatory arthritis. AB - The effects of detraining subsequent to strength training on neuromuscular function were examined in 39 recent-onset rheumatoid arthritis (RA) patients. Eighteen age- and sex-matched healthy people (H) served as controls. Patients were randomly allocated either to the experimental group (PE), who carried out progressive strength training for 6 months, or to the control group (PC), who maintained only their habitual physical activities. After 6 months, PE returned to their earlier physical activities and strength training was terminated. At baseline, the maximal strength of the trunk extensors (not significant), grip strength and maximal dynamic strength and the shape of the force-time curve of the knee extensors were lower in PE and PC (P < 0.05-0.001) than in H. Strength training in PE led to remarkable increases (P < 0.05-0.001) in the maximal strength of all muscle groups without changes in the shape of the force-time curve. The increases in muscle strength in PE obtained by strength training were lost to a great degree during the detraining period for the isometric trunk extension (P < 0.01) and flexion (P < 0.01) strength and for the dynamic knee extension strength (P < 0.05), but not for the grip strength. In PC, trunk extension and flexion strength decreased significantly throughout the study period. At the post-test, all the strength values in both patient groups were much lower than in H. RA is a chronic disease which seems to need continuous physical exercise with sufficient intensity to minimize/prevent the loss of muscle strength and functional capacity. PMID- 9374925 TI - Combination of sulphasalazine and methotrexate versus the single components in early rheumatoid arthritis: a randomized, controlled, double-blind, 52 week clinical trial. AB - To compare the efficacy of sulphasalazine, methotrexate, and the combination of both in patients with early rheumatoid arthritis (RA), not treated with disease modifying anti-rheumatic drugs previously, we conducted a double-blind, double dummy, controlled, clinical trial. One hundred and five patients with active, early RA, rheumatoid factor and/or HLA DR1/4 positive were randomized between sulphasalazine (SSZ) 2000 (maximum 3000) mg daily, or methotrexate (MTX) 7.5 (maximum 15) mg weekly, or the combination (COMBI) of both, and were followed up by a single observer for 52 weeks. The mean change over time per patient, including all visits, in Disease Activity Score (DAS) was: SSZ: -1.6 (95% CI -2.0 to -1.2); MTX: -1.7 (-2.0 to -1.4); COMBI: -1.9 (-2.2 to -1.6); the difference week 0-week 52 (SSZ, MTX, COMBI respectively); DAS: -1.8, -2.0, -2.3, Ritchie articular index: -9.2, -9.5, -10.6, swollen joints: -9.2, -12.4, -14.3, erythrocyte sedimentation rate: -17, -21, -28. Nausea occurred significantly more in the COMBI group. The numbers of drop-outs due to toxicity were SSZ 9, MTX 2, COMBI 5. In conclusion, there were no significant differences in efficacy between combination and single therapy, only a modest trend favouring COMBI. The results of MTX and SSZ were very comparable. Nausea occurred more often in the COMBI group: the number of withdrawals due to adverse events did not differ significantly. PMID- 9374926 TI - Predisposing factors in sulphasalazine-induced systemic lupus erythematosus. AB - The aim of this study was to define predisposing factors in patients with sulphasalazine-induced systemic lupus erythematosus (SLE). Eleven patients with onset of SLE or SLE-like syndromes during sulphasalazine treatment are reported. Before the onset of SLE, five of the patients suffered from rheumatoid arthritis (RA), one from psoriatic arthropathy (PsoA), two from juvenile chronic arthritis (JCA) and three from ulcerative colitis (UC). At the time of diagnosis of drug induced SLE, analysis of antinuclear antibodies (ANA), anti-double-stranded DNA antibodies (anti-dsDNA), anti-histone antibodies (anti-histones), acetylator status of the enzyme N-acetyltransferase 2 (NAT2) and HLA classification were performed. All patients were anti-DNA positive at disease onset and were determined to be slow acetylators. HLA A1 occurred in 4/10 patients, B8 in 5/10. HLA DR 3 was represented in one patient and DR 3(17) in five patients. The DQA1* 0501 allele was observed in 7/10 patients and DQB1 0201* in 6/10. Persistent SLE and development of nephritis were noted in patients with long duration of treatment and high cumulative dose of sulphasalazine (> 1000 g). In sulphasalazine-induced SLE, slow acetylator genotype and HLA haplotypes associated with idiopathic SLE seem to predict disease induction. Further, as the risk of developing persistent SLE and nephritis increases with long-standing sulphasalazine medication, it is of importance to monitor the patients with regard to signs of SLE during the entire treatment period. PMID- 9374927 TI - Successful therapy with danazol in refractory autoimmune thrombocytopenia associated with rheumatic diseases. AB - The objective was to assess the efficacy of therapy with danazol in refractory immune thrombocytopenia associated with different rheumatic diseases. Patients with severe immune thrombocytopenia (platelet counts < 40 x 10(9)/l) with a bone marrow biopsy showing megakaryocytes in normal or increased number and normal morphology were included if they fulfilled at least one of the following criteria: (a) thrombocytopenia refractory to prednisone (> or = 1 mg/kg/day during > or = 4 weeks); (b) patients requiring an unacceptably high dose of prednisone for > 2 months (prednisone dose > or = 20 mg/day); (c) no response to at least another drug besides corticosteroids. Other causes of thrombocytopenia were excluded. They were treated with danazol (100-200 mg q.i.d.) and followed for at least 12 months. Four patients diagnosed with systemic lupus erythematosus, two with rheumatoid arthritis and one with primary antiphospholipid syndrome met the inclusion criteria. All of them achieved acceptable platelet counts within the first 4 weeks of danazol therapy that allowed the prednisone dosage to be tapered. No important side-effects related to danazol therapy were observed. Danazol therapy seems to be a useful and well tolerated treatment for refractory immune thrombocytopenia associated with different rheumatic diseases. PMID- 9374928 TI - A retrospective review of yttrium-90 synovectomy in the treatment of knee arthritis. AB - We reviewed the case notes and X-rays of all patients with knee arthritis treated with yttrium-90 for the first time at a single institution from November 1981 to November 1995. Outcomes were assessed as 'improved' or 'not improved' by review of the case notes at 3, 6 and 12 months, and by the absence of further intra articular (IA) steroid injections. Of the 121 knees treated, 87 had adequate follow-up information to allow an assessment of outcomes. Overall, 46% (95% CI 36 57) were improved at 12 months and 37% (95% CI 27-47) had no further IA injections (mean follow-up of 3.5 yr). Knees with osteoarthritis (OA) fared significantly worse with 10% (95% CI 0-29) vs 51% (95% CI 39-63) improved at 12 months (P < 0.05). Knees younger than 30 appeared to do better with 78% (95% CI 51-100) vs 28% (95% CI 17-45) having no further IA injections (P < 0.02). Knees with normal X-rays (Kellgren grade 0-1) did significantly better than those with more severe radiographic abnormalities (Kellgren grade 3-4), with 56% (95% CI 40 73) vs 24% (95% CI 8-40) improved (P < 0.01). Radiosynovectomy with yttrium-90 for knee arthritis appears to be of less value for patients with OA or with secondary OA changes on X-ray, and may be of more value for younger patients and those with spondyloarthropathies. PMID- 9374929 TI - Life events and disability in rheumatoid arthritis: a European cohort. AB - The objective was to study the relationship between life events (LE) and the clinical status of patients suffering from recently diagnosed rheumatoid arthritis (RA) in a 2 yr follow-up. As part of a multicentre European cohort study, 370 French and Dutch patients were questioned three times at 1 yr intervals about LE which had occurred in the previous year. Three criteria were used to quantify the degree of disease activity (Ritchie's index), the level of functional disability [Health Assessment Questionnaire (HAQ)] and perceived health [Overall Evaluation of Health (OEH)]. Total LE and desirable LE showed a weak negative correlation with the HAQ scores. On the other hand, death-related LE did not seem to modify patient status. The higher the number of health associated LE, the greater the deterioration in HAQ and OEH scores. The results indicate that LE do not affect the course of early RA in a spectacular manner. PMID- 9374931 TI - Routine synovial fluid culture: is it necessary? Lessons from an audit. AB - An estimated third of rheumatologists send aspirated synovial fluid samples for culture routinely during the course of management of their patients irrespective of the underlying diagnosis. This is done apparently even when sepsis is not suspected. This audit of 507 synovial fluid culture requests revealed that positive bacterial growth was rare even when sepsis was queried on the request forms but none was positive in any of the routine samples. Our findings throw doubt on the value of routine synovial fluid culture. We recommend that such cultures are undertaken when infection is a possibility and in immuno-compromised patients. An average health district would save pounds 3000 per annum if such a policy was adopted, but across the National Health Service as a whole the total expenditure saved on this unnecessary investigation would be considerable. PMID- 9374930 TI - Neoral--new cyclosporin for old? AB - Cyclosporin A is now well established as an effective second-line drug to treat rheumatoid arthritis. In April 1995, the microemulsion-based formulation of cyclosporin (Neoral) was introduced based on its increased bioavailability at 'no extra cost'. There may have been concerns that with increased bioavailability of Neoral, some patients might experience increased toxicity, particularly if transferring from Sandimmun to Neoral at the same dose. We describe our experience of 51 patients treated with Neoral--39 with rheumatoid arthritis, six with psoriatic arthritis and the remainder with a variety of diseases, including Behcet's, systemic lupus erythematosus and juvenile chronic arthritis. All patients continued their other medication including non-steroidal anti inflammatory drugs and analgesics. Five continued low dose prednisolone (average 7.5 mg per day) all patients were monitored for safety and efficacy throughout their treatment according to standard protocol. Five patients were enrolled in a study of efficacy and safety where the dose of cyclosporin was reduced to 2.5 mg/kg/day at the time of conversion, i.e. to Neoral 2.5 mg/kg/day; 19 patients were converted dose for dose, cyclosporin A dose range 2.5-4 mg/kg/day converted to Neoral dose range 2.5-4 mg/kg/day and 27 patients started Neoral de novo. We conclude that cyclosporin is a useful disease modifying anti-rheumatic agent, and our experience suggests that the new formulation, Neoral, has a similar safety and efficacy profile to the original preparation (Sandimmun). Neoral was relatively easy to manage and we noted a slight reduction in dose when compared to Sandimmun. With dose adjustments over 18 months the mean dose for patients with RA fell from 3.2 to 2.7 mg/kg/day and of the 27 patients starting Neoral de novo only seven required an increased dose above 2.5 mg/kg/day in order to establish efficacy. PMID- 9374933 TI - Vasculitis and bacteraemia with Yersinia enterocolitica in late-onset systemic lupus erythematosus. AB - We report a case of Yersinia enterocolitica 0.9 septicaemia complicating systemic lupus erythematosus in an elderly male patient. The infection gave rise to digital vasculitis, fevers and general malaise on top of pre-existing articular symptoms. Features of Yersinia septicaemia may mimic some of the signs of lupus. PMID- 9374932 TI - An unusual case of familial Mediterranean fever. AB - Familial Mediterranean fever (FMF) is an inherited disorder characterized by recurrent self-limiting attacks of joint, chest and abdominal pain associated with fever. The most serious complication in FMF is the development of amyloidosis, which usually leads to death from renal failure within a year. The use of colchicine has dramatically reduced this complication. We describe a 56-yr old female patient with FMF in whom the arthropathy became the dominant clinical feature, resulting in the development of an erosive large and small joint arthritis during the course of the disease. The patient was treated with colchicine, but despite this, later developed amyloidosis confirmed on rectal biopsy, and chlorambucil was added to her treatment. For 10 yr, she also suffered intermittent abdominal pain and had terminal ileal changes suggestive of Crohn's disease. However, she was found to have ischaemic colitis at post mortem secondary to amyloidosis. Ischaemic bowel disease is an extremely unusual event in FMF. Other factors which may have contributed to the terminal ischaemia in this patient include anaemia secondary to blood loss and a drug-induced myelodysplasia, as well as hypotension during the final septicaemic illness. Clinicians should consider an ischaemic colitis as a possible differential diagnosis of abdominal pain in patients with FMF even in the absence of other clinical evidence of systemic amyloidosis. PMID- 9374934 TI - Hypokalaemic alkalosis, acquired Gitelman's and Bartter's syndrome in chronic sialoadenitis. AB - Two patients with chronic sialoadenitis had features of Bartter's and Gitelman's syndrome, respectively. The main complaints were leg paraesthesiae and acute arthritis. A good response to oral K+ supplementation, allopurinol and low-dose prednisone was obtained. The features of Sjogren's-related renal diseases are reviewed. PMID- 9374936 TI - Longitudinal stress fractures of the tibia: report of three cases. PMID- 9374935 TI - Anti-tumour necrosis factor therapy ameliorates joint disease in a chronic model of inflammatory arthritis. PMID- 9374937 TI - Gout due to xanthine derivatives. PMID- 9374938 TI - More on enterococcal osteoarticular infections: vertebral osteomyelitis. PMID- 9374939 TI - Tattooing-induced psoriasis and psoriatic arthritis. PMID- 9374940 TI - Chlamydia pneumoniae antibodies in myalgia of unknown cause (including fibromyalgia) PMID- 9374941 TI - Diagnostic criteria for work-related upper limb disorders. PMID- 9374942 TI - The contribution of the Rabin Medical Center to the field of rheumatology. PMID- 9374943 TI - Tricuspid endocarditis following a Papanicolaou smear: case report. AB - Infective endocarditis is an uncommon complication of obstetrical and gynecological practice and has not been reported in the literature to be associated with Papanicolaou smears. The authors report a nonintravenous drug user who developed group B streptococcal endocarditis of the tricuspid valve following a routine Papanicolaou smear. She required surgical excision of the valve and replacement after failed antibiotic therapy. PMID- 9374944 TI - Coronary to bronchial artery anastomosis in patients with noncyanotic cardiopulmonary disease: report of seven cases. AB - An angiographically visible coronary to bronchial artery anastomosis was found in seven (0.12%) of 6045 patients with noncyanotic cardiopulmonary disease who underwent coronary angiography between 1989 and 1995. Aortitis syndrome was associated with four patients, whereas pulmonary embolism, aortic regurgitation and vasospastic angina were the diagnoses in the others. Coronary stenotic lesions were not observed in any patients. In five of six patients who underwent pulmonary perfusion scintigraphy, perfusion defect was observed in the area supplied by the bronchial artery, which had the anastomosis to the coronary artery. In each patient this anastomosis seemed to function as collateral circulation, compensating for decreased perfusion in either the lung or the heart. When coronary to bronchial artery anastomosis is found, ischemic conditions in either the lung or the heart are likely. PMID- 9374945 TI - Incidental detection of an aortic valve papillary fibroelastoma by echocardiography in an asymptomatic patient presenting with hypertension. AB - Papillary fibroelastomas are rare, frond-like tumours of uncertain etiology seen on cardiac valves, uncommonly found antemortem. They carry a significant risk of embolization, making their detection and excision during life an important issue. A case of an aortic valve papillary fibroelastoma is described, which was found at echocardiography in a patient being assessed for previously unrecognized, severe hypertension. PMID- 9374946 TI - Ticlopidine-associated pancytopenia: implications of an acetylsalicylic acid alternative. AB - Ticlopidine is an antiplatelet agent that has been proven efficacious in preventing vascular events in patients with a history of vasculopathy. Neutropenia is a significant adverse effect and pancytopenia is rarely reported. A fatal case of pancytopenia associated with unmonitored use of ticlopidine is presented. A 59-year-old woman presented with severe pneumonia and profound neutropenia (absolute neutrophil count 0%). She deteriorated with development of acute respiratory distress syndrome and a marked reduction in trilineage hematopoiesis. Despite prompt marrow response to granulocyte macrophage colony stimulating factor (GM-CSF) and cessation of ticlopidine, appropriate antibiotics and other supportive therapy, she died 17 days after admission. Hematological monitoring is imperative to identify potential complications: if discovered late, there may be a role for GM-CSF for marrow support. Ticlopidine is indicated for patients intolerant of or nonresponsive to acetylsalicylic acid therapy. As the use of ticlopidine increases, clinicians must be aware of potential life threatening complications associated with its use and monitor appropriately. PMID- 9374948 TI - Efficacy of a low dose nifedipine GITS (20 mg) in patients with mild to moderate hypertension. AB - Nifedipine gastrointestinal therapeutic system (GITS) is a once-a-day formulation of nifedipine providing stable plasma concentrations over the entire 24 h dosing interval. The antihypertensive efficacy of a new 24 mg formulation was evaluated in 187 patients in 15 centres across the country. After a two-week placebo washout, mild to moderate hypertensive patients were randomized in a double blind, parallel design to four weeks of placebo or nifedipine GITS 20 mg once daily treatment. Changes in office blood pressure (BP) were noted for each group. Ambulatory BP was also monitored at baseline and after four weeks of placebo/nifedipine therapy in a subgroup of 66 patients at five centres. After four weeks of treatment, office BP in the placebo group decreased by 5.0 +/- 11.9/5.4 +/- 7.9 mmHg compared with 9.3 +/- 11.2/8.6 +/- 7.4 mmHg in the nifedipine GITS group. Both systolic and diastolic BP were significantly decreased (P = 0.006 and P = 0.001 for systolic and diastolic, respectively) more with nifedipine GITS. Heart rate did not significantly differ between the groups at baseline nor after four weeks of treatment. The percentage of responders- defined as having a sitting diastolic BP less than 90 mmHg or a decrease from baseline of 10 mmHg--was 57% for nifedipine GITS versus 32% for placebo (P < 0.05). Daytime average diastolic blood pressure was 86.4 +/- 6.4 mmHg in the nifedipine GITS 20 mg group compared with 93.7 +/- 8.9 mmHg in the placebo group (P < 0.02). The maximum antihypertensive effect of nifedipine during ambulatory monitoring was similar to the reduction in BP observed in the office at the end of the dosing interval. The frequency of spontaneously reported adverse events was similar for nifedipine GITS (32.3%) and placebo (37.2%). These results indicate that 20 mg of nifedipine GITS is efficacious in decreasing BP, with good 24 h control and an incidence of adverse events similar to that of placebo treated patients. PMID- 9374947 TI - Patterns of compliance with once versus twice daily antihypertensive drug therapy in primary care: a randomized clinical trial using electronic monitoring. AB - OBJECTIVE: To evaluate patterns of compliance with once versus twice daily administration of antihypertensive therapy (primary-outcome measure) and relevance of partial compliance for blood pressure control (secondary outcome measure). DESIGN: Multicentre, nonblinded, parallel group randomized design. SETTING: Nonacademic primary care practices across Canada. STUDY POPULATION: Patients with mild essential hypertension (diastolic blood pressure 95 to 110 mmHg) of either sex (40% women), age 18 to 80 years (average 55 years). One hundred and ninety-eight patients were randomized to active treatment; 14 patients discontinued the study because of side effects. INTERVENTIONS: After a four-week placebo run-in period, patients were randomized to amlodipine 5 mg once a-day or diltiazem slow release formulation (SR) 90 mg twice daily. Doses were increased to 10 mg and 180 mg to achieve sitting diastolic blood pressure of 90 mmHg or less. OUTCOME MEASURE: During 20 weeks on active treatment, compliance was assessed by pill counts and medication event monitoring system (MEMS), assessing percentage of prescribed doses taken, percentage days correct doses taken, percentage prescribed doses taken on time and blood pressure control as determined by office blood pressure measurement. RESULTS: The percentage prescribed doses taken (by either pill count of MEMS) showed a high degree of compliance, similar for the two treatments. However, other parameters of compliance were significantly better with once versus twice daily therapy. Partial compliance (less than 80% by pill count) led to less blood pressure control with the short acting diltiazem, but did not affect blood pressure control for the long acting amlodipine. Side effects profiles did not differ between the two treatments. CONCLUSIONS: Within the constraints of a clinical trial, hypertensive patients in primary care show a high degree of overall compliance with once or twice daily pill-taking, but patterns of pill-taking are more erratic with twice versus once daily medication, particularly in men. The results suggest that the negative consequences of partial compliance for blood pressure control can be offset by choosing agents with a duration of action well beyond the dosing interval. PMID- 9374949 TI - Coarctation of the aorta: tailoring the surgical approach. AB - OBJECTIVE: To employ a flexible approach for repairing coarctation of the aorta in an attempt to minimize residual coarctation and avoid the use of synthetic material. DESIGN: Retrospective study of consecutive children undergoing surgical repair of coarctation of the aorta. SETTING: Walter C Mackenzie Health Sciences Centre, University of Alberta, Edmonton, Alberta. PATIENTS: Children presenting with coarctation of the aorta between June 1993 and October 1996 (n = 42), treated by one surgeon. INTERVENTIONS: Children had repair by one of three methods: subclavian flap angioplasty for discrete juxtaductal coarctation, 17 (40%); resection and end-to-end anastomosis, 13 (31%); and resection with extended transverse arch repair, 12 (29%). MAIN RESULTS: Follow-up was 22 +/- 2 months. The preoperative mean arm-leg gradient was 23 +/- 3 mmHg and postoperatively was 4 +/- 2 mmHg (P < 0.001). In late follow-up, five children developed a significant gradient (end-to-end anastomosis, one; transverse arch repair, two; subclavian flap angioplasty, two) necessitating balloon dilation, one of whom (subclavian flap angioplasty) eventually required end-to-end repair. Another child, who had a subclavian flap angioplasty, underwent transverse arch repair at the time of complete cardiac repair. There was one perioperative death in a child who was in extremis preoperatively and three late deaths in children with additional complex intracardiac anomalies. CONCLUSIONS: A flexible surgical approach with avoidance of synthetic material and low threshold for extended repair has yielded good early and intermediate term results. PMID- 9374950 TI - Predictors of same-admission cardiac catheterization in patients with acute ischemic syndromes. AB - BACKGROUND: Various strategies exist for the use of cardiac catheterization in unstable angina or non-Q wave myocardial infarction. At the authors' institution, the overall volume of cardiac catheterization has increased in recent years. OBJECTIVE: To investigate whether this increased volume of cardiac catheterization was due to adoption of a more invasive approach to the management of patients with acute ischemic syndromes. DESIGN: A retrospective cohort study was conducted using detailed chart review of coronary care unit admissions during 1990/91 and 1993/94. SETTING: A university-affiliated tertiary care referral centre with facilities for cardiac catheterization. PATIENTS: One hundred patients randomly selected from among those with unstable angina, non-Q wave myocardial infarction or chest pain not yet diagnosed in each of the study years. Detailed follow-up was complete for all patients. OUTCOME MEASURE: The use of cardiac catheterization during the index admission was documented. MAIN RESULTS: There was a trend towards more frequent use of same admission cardiac catheterization in the later period (21% [CI 14% to 31%] versus 12% [CI 7% to 20%], P = 0.09). However, after controlling for baseline characteristics and in hospital events, the year of admission did not independently predict the use of catheterization (P = 0.60). By multivariate logistic regression, recurrence of chest pain and evidence of myocardial necrosis were most closely associated with same-admission cardiac catheterization. CONCLUSIONS: Although clinical factors partially explain the increased use of catheterization over time, there may have also been shift towards a more aggressive practice style at the authors' institution. Further study is needed to address this possibility. PMID- 9374951 TI - Effects of amlodipine versus enalapril on left ventricular remodelling after reperfused anterior myocardial canine infarction. AB - OBJECTIVE: To compare the effects of the calcium channel blocker amlodipine with those of the angiotensin-converting enzyme (ACE) inhibitor enalapril on left ventricular (LV) remodelling and dysfunction during healing after reperfused anterior myocardial infarction (MI). ACE inhibitors and reperfusion are known to limit LV remodelling after MI. However, the effects of ACE inhibitors and calcium channel blockers on LV remodelling after reperfused MI have not been compared. METHODS: Changes in LV topography and function (quantitative echocardiograms) and hemodynamics were measured over six weeks in dogs that were randomized 24 h after reperfusion, done after 2 h of anterior MI, to oral amlodipine (5 mg bid; n = 7), enalapril (5 mg bid; n = 6) or no drug (controls; n = 6) for six weeks. Postmortem LV topography was measured at six weeks. RESULTS: Scar sizes after six weeks were similar in the three groups. Both enalapril and amlodipine reduced the rate pressure product, but decreases in mean arterial and left atrial pressures were more sustained over six weeks with enalapril. Compared with controls over six weeks, both enalapril and amlodipine preserved LV volumes, global ejection fraction, regional function and infarct segment length, but enalapril blocked the increase in non-infarct wall thickness, attenuated the infarct wall thickness, preserved shape and decreased global LV mass more than amlodipine. Sham-operated dogs (n = 3) showed no significant structural changes. CONCLUSIONS: Both enalapril and amlodipine preserve LV volumes and function during healing after reperfused MI, but enalapril more effectively limits hypertrophy, attenuates infarct wall thickness and preserves shape. PMID- 9374952 TI - Is there a role for antioxidant vitamins in the prevention of cardiovascular diseases? An update on epidemiological and clinical trials data. AB - OBJECTIVES: To review prospective epidemiological studies and randomized clinical trials regarding the role of antioxidant vitamins (vitamins E and C and beta carotene) in the prevention of cardiovascular diseases. DATA SOURCES: Computerized (MEDLINE and Science Citation Index) and manual searches on the role of antioxidant vitamins in cardiovascular disease management. STUDY SELECTION: Only prospective epidemiological studies and double-blind, controlled, randomized clinical trials, including at least 100 participants and providing sufficient data to allow quantitative estimation of the effects of vitamin intake were included. Retrospective epidemiological evaluations and other retrospective studies were excluded. Geographic correlation studies of population-based intake of antioxidants and cardiovascular disease rates were also excluded due to the potential large impact of confounders in cross-sectional analyses. DATA SYNTHESIS: Relative risk was evaluated for all prospective epidemiological studies. Relative risk reductions were evaluated for clinical trials. The Mantel Haenszel method was used to estimate the relative risk reduction in clinical trials when not calculated in the original publication. A formal meta-analysis was not performed because very significant differences among study populations, type (supplemental versus dietary) and dosage of antioxidant vitamins, duration of follow-up and overall study design exist for both epidemiological investigations and clinical trials, and the pooling of study results could be misleading. CONCLUSIONS: Prospective epidemiological investigations suggest a reduction in cardiovascular risk associated with increased intake of antioxidant vitamins, particularly vitamin E. Randomized clinical trials remain inconclusive with regard to the role of vitamin E in cardiovascular protection. The large, randomized clinical trials of beta-carotene in primary prevention show no effect and potential for harm associated with the use of beta-carotene. There are inconclusive and insufficient epidemiological and clinical trial data with regard to the role of vitamin C in cardiovascular protection. Overall, it is recommended that wide-spread use of antioxidant vitamins in cardiovascular protection should not be instituted and should await the results of further ongoing clinical trials. PMID- 9374954 TI - Lowering the rate of antibiotic resistance. PMID- 9374955 TI - Inducible ischemia after MI. PMID- 9374953 TI - Common cancers--genetics, origin, prevention, screening: Parts I and II. AB - Carcinogenesis is a stepwise process that occurs through mutations of cancer related genes. Five or more genes must be mutated before malignant transformation occurs in most adult cancers; in some childhood cancers as few as two mutated genes may be sufficient. A rare inherited mutation of a critical gene may predestine cancer to occur in one or more sites. This germline mutation is present in virtually every cell in the body, except half of the germ cells, which do not contain the mutated gene in their haploid chromosome set. These and other genes have been used to piece together a puzzle of regulatory systems that govern cell division and proliferation, as well as apoptosis or programmed cell death. Mutations of these genes result not only in increased cell proliferation but also in diminished cell death. Most genetic changes that occur during carcinogenesis are not inherited or germline. They are acquired after birth and are called somatic mutations. A somatic mutation affects only the mutated cell and its progeny. Each time a cell divides, there is a chance of somatic mutation, and therefore there always is a low, background risk for cancer and other malignant lesions. A far more prevalent cause of cancer-related death in the United States is environmental exposure. Such exposure causes somatic mutations of cancer related genes through direct damage to DNA or through alteration of proliferation or cell death, which enhances the baseline risk for mutation. As carcinogenesis becomes understood, interventions may be designed that selectively interfere in important steps. Screening for cancer is based on the premise that one can treat a patient for a cancer that has not spread from its primary site. Nevertheless, cancer screening is controversial and often confusing. Issues of costs, risks versus benefits, physical time and effort, and patient compliance all affect the clinician's view of screening, often to the extent that the true value of this approach to cancer control is underappreciated and underutilized. A clinician should consider the following questions when assessing the priority, scope, and intensity of cancer screening. Is the cancer an important public health problem? Can preclinical stages be detected and cured? Are effective screening tests available? Are the tests feasible and acceptable? Have screening programs reduced cancer-specific mortality? Is the screening program cost effective? Is screening generally recommended? There is clear-cut evidence of benefit from screening for cancer of the cervix, breast, colon and rectum, and skin and some specific genetic syndromes. Evidence of survival benefit from screening for prostate cancer is lacking, although prostate specific antigen screening is widely used. Screening for lung and ovarian cancer is ineffective. PMID- 9374956 TI - Detecting depression with two questions. PMID- 9374957 TI - Management of gestational diabetes. PMID- 9374958 TI - Education to prevent low back injuries. PMID- 9374959 TI - Treating acute coronary insufficiency with antibiotics. PMID- 9374960 TI - Microalbuminuria and mortality in type 2 diabetes. PMID- 9374961 TI - Trial of labor with prior vertical cesarean incision. PMID- 9374962 TI - Lifelong self-directed learning using a computer database of clinical questions. AB - Physicians often have self-perceived knowledge gaps when they are seeing patients. Traditional continuing medical education is designed to meet the knowledge gaps of groups rather than individual physicians with specific patient problems. Physicians with clinical information needs are advised to critically evaluate high-quality original research in order to practice "evidence-based medicine." But this advice may be unrealistic for busy clinicians. We propose a system for documenting self-perceived information needs using a computer database. Concise answers to these needs are included in the database along with reference citations supporting the answers. The system tracks continuing education efforts, directs patient care decisions, and focuses lifelong learning on relevant topics. We emphasize the importance of being sensitive to personal information needs and the benefits of maintaining a record of these needs. PMID- 9374963 TI - A spectrum of health policy methods: lessons from the British. AB - Two vignettes about two health care systems (actually, one system and one non system). Two different cancer screening programs. Two different approaches to developing a national health policy. This is not an issue of money; either approach could be used inside any budget. One approach looks at the entire health care delivery system, trying to maximize gain while assuring appropriate care is provided. The other approach tries to get votes. Is there any doubt which is the better method? PMID- 9374964 TI - The primary care science of the ordinary: little stuff as big stuff. PMID- 9374965 TI - Gowning: effects on patient satisfaction. AB - BACKGROUND: Given an extensive literature regarding the doctor-patient relationship, it appears curious that gowning status has received so little attention. The present study examined potential effects of gowning as opposed to not gowning patients at the point of presenting problem. Specifically, effects that gowning status might have on patients' trust in their physician, as well as overall duration of clinic visit, were investigated. METHODS: Patients (N = 1500) were randomly assigned to gown or non-gown status on arrival for clinic visit. Subsequent screening following predetermined guidelines resulted in 895 subjects participating in the study. Fifty-one percent of these patients (n = 455) fully completed the Trust in Physician Scale. Total time data from check-in to checkout, by gowning status, were kept on all patients. RESULTS: No significant effects for gowning status were found with respect to patients' trust in their physician or duration of clinic visit. There were also no significant interactions between gowning status, patient sex, physician sex, patient age, or patient education. Significant findings were demonstrated whereby younger patients and patients seeing a doctor for the first time reported less trust in their physician. CONCLUSIONS: There is not sufficient evidence, to date, to suggest that gowning status has a significant impact on the doctor-patient relationship or the duration of clinic visit. PMID- 9374966 TI - Diagnosis of acute bronchitis in adults: a national survey of family physicians. AB - BACKGROUND: The purpose of this study was to determine how family physicians in the United States diagnose acute bronchitis in otherwise healthy adults. METHODS: A 33-item questionnaire on the diagnosis and treatment of acute bronchitis was mailed to a random sample of 500 physicians who are members of the American Board of Family Practice. RESULTS: Two hundred sixty-five physicians responded. Of those who did not respond, 32 could not be located. Of those who did respond, 10 were either retired or were practicing in another specialty. The net response rate was 56% (255/458). Responding physicians stated that character of cough and sputum production are the most important items used in diagnosing acute bronchitis. Fifty-eight percent indicated that the cough should be productive, and 60% stated that the sputum should be purulent. Seventy-two percent of respondents did not feel that wheezing or rhonchi need to be present. Younger physicians and those who selected antibiotics as their first treatment choice were more likely to define acute bronchitis as the presence of a productive cough with purulent sputum (P < .05). Physicians from an academic setting were more likely to define acute bronchitis as a productive cough (P < .05). Thirty-six percent of physicians from practices serving populations with > or = 60% managed care patients included wheezing or rhonchi in the definition of acute bronchitis, compared with 26% of all others (P < .05). CONCLUSIONS: Variations in the diagnosis of acute bronchitis in otherwise healthy adults can be attributed to physician age, treatment choice, and practice setting. A significant number of family physicians did not require a productive cough as part of the diagnostic criteria for acute bronchitis. This finding needs to be considered in studies evaluating treatment. Additional qualitative studies are necessary to identify other factors involved in diagnosing acute bronchitis. PMID- 9374967 TI - Health outcomes of women exposed to household alcohol abuse: a Family Practice Training Site Research Network (FPTSRN) study. AB - BACKGROUND: There is a paucity of knowledge about the effects of exposure to alcohol abuse in the household on women who do not abuse alcohol. The purpose of this study was to determine whether women who did not abuse alcohol demonstrated any health-related adverse effects because they lived with family members who did abuse alcohol. METHODS: This study was a historical prospective survey of female patients at five primary care practices. Survey instruments included the CAGE questionnaire, a five-item screening test for exposure to alcoholism, and the Medical Outcomes Study 36-item Short Form Health Survey (MOS SF-36). Patient records were examined for specific diagnoses. RESULTS: A total of 267 patients completed the questionnaires and had complete medical records available for analysis. Forty-two (15.7%) potential alcohol abusers were excluded from the sample leaving a working total of 225; 70 (31.1%) were potentially exposed to alcoholism in the household. Women exposed to alcohol abuse in the home did not experience an increased risk for the medical diagnoses studied, but they did demonstrate decreased health-related quality of life as measured by the MOS-SF-36 for the following scales: role physical (P = .025), role emotional (P = .038), social functioning (P = .001), bodily pain (P = .016), and mental health (P = .040). CONCLUSIONS: Women exposed to alcohol abuse in the household are more likely to perceive themselves as less healthy. Although they may not have received a clinical diagnosis of depression, they are more likely to feel depressed. The extent to which subjects' health-related quality of life is influenced by exposure to alcohol abuse suggests that the medical diagnosis may be insensitive as a description of health status in this population. PMID- 9374969 TI - Comparisons of ambulatory blood pressure monitoring and repeated office measurements in primary care. AB - BACKGROUND: The accuracy of office blood pressure (BP) readings is questionable because of blood pressure variability and measurement errors. The primary aim of this study was to determine the number of office visits required to optimize the estimation of usual blood pressure in older adults in primary care. METHODS: Ambulatory blood pressure monitoring was used to define usual blood pressure in an observational study of 75 randomly selected family practice patients. Each subject made six visits for office BP measurements and had 24-hour ambulatory BP monitoring done twice. Mean office BP, based on one through six visits, was compared with mean ambulatory BP. RESULTS: The sample consisted of 29 men and 46 women; 18 were black and 57 were white. Twenty-one subjects were taking antihypertensive medication. The mean age +/- 1/standard deviation (SD) was 60 (+/- 8) years. The correlation between mean office BP and mean ambulatory BP rose with the number of visits averaged, with most of the gain obtained within 3 visits. The maximal correlation for 24-hour ambulatory BP was r = .85/.75 (systolic/diastolic) (P < .01). However, even when using average office BP over six visits to estimate mean ambulatory BP, a discrepancy of > or = 10 mm Hg between estimated and observed ambulatory BP levels persisted in 18% to 20% of subjects. CONCLUSIONS: Readings from at least three office visits should be averaged to estimate usual blood pressure. It should be noted, however, that important discrepancies between estimated and observed mean ambulatory BP persist even after readings taken over six visits. Ambulatory BP monitoring probably provides unique information about usual blood pressure that cannot be captured by repeated office BP readings. PMID- 9374968 TI - Patient and physician satisfaction with an outpatient care visit. AB - BACKGROUND: The purpose of this study was to identify factors contributing to patient and physician satisfaction during outpatient care visits, and to determine the degree to which physician and patient satisfaction are related. METHODS: The sample (N = 250) was drawn from the outpatient practice of the University of South Carolina Department of Family and Preventive Medicine. Opinions were obtained by self-administered written questionnaires for physicians and by interviews with patients conducted by second-year medical students. RESULTS: Most encounters (88%) were satisfying for the physician. Resident physicians reported greater satisfaction than did faculty. Physicians were most satisfied with encounters in which they believed they had adequate time, were competent to address patient problems, and communicated successfully with the patient. Patient satisfaction was high (78% highly satisfied). Patients were more likely to be fully satisfied if they believed themselves to be in good health, did not wait long, and had health insurance. Unperceived patient dissatisfaction was associated with waiting time and a belief that the physician did not pay attention. No relationship was found between patient satisfaction and physician satisfaction. CONCLUSIONS: The majority of patient care encounters were satisfying for both participants. The pervasive effect of waiting time on patient satisfaction emphasizes the need for careful scheduling. Lower satisfaction among faculty physicians should be explored to identify possible interventions to prevent physician burnout. Pressures from managed care organizations may decrease physician satisfaction if these take the form of reducing the time available for each patient or restricting physicians' ability to seek subspecialist consultation. PMID- 9374970 TI - Anticonvulsant hypersensitivity: an unfortunate case of triple exposure to phenytoin. AB - Anticonvulsant hypersensitivity manifests 2 to 12 weeks after patients start taking phenytoin, phenobarbital, or carbemazepine. The syndrome begins with fever followed by a rash that can progress to erythema multiforme, toxic epidermal necrolysis, and multi-organ system involvement. Other common manifestations include lymphadenopathy, facial edema, eosinophilia, and elevated transaminase levels. Anticonvulsant hypersensitivity can be fatal in 5% to 50% of patients if hepatic involvement or toxic epidermal necrolysis occurs. Most evidence regarding the etiology points to a genetically related defect in the detoxification enzyme. Early recognition is important in order to discontinue drug therapy. Continuity of care assists in prevention of re-exposure. Treatment includes supportive measures and steroids. All patients with anticonvulsant hypersensitivity should wear a medical identification bracelet. PMID- 9374971 TI - Penile cancer in elderly circumcised man. PMID- 9374972 TI - 50th anniversary of community internal medicine at Mayo. PMID- 9374973 TI - Intra-arterial thrombolysis in acute basilar artery thromboembolism: the initial Mayo Clinic experience. AB - OBJECTIVE: To investigate the feasibility of intra-arterial thrombolysis in acute basilar artery thrombosis. DESIGN: We reviewed a consecutive series of patients in whom intra-arterial thrombolysis was performed during the period from 1994 to 1996. MATERIAL AND METHODS: Intra-arterial thrombolysis with urokinase was done in an attempt to recanalize the basilar artery in a series of nine patients with basilar artery thrombosis admitted to the neurologic intensive care unit. At the time of initial assessment, all nine patients had major neurologic deficits attributable to brain-stem ischemia, including two patients with locked-in syndrome. RESULTS: Recanalization of the basilar artery system was successful in seven of the nine patients (a range of 2 to 13 hours after the ictus). Failure to recanalize the basilar artery occurred in two patients, who died after progressing to coma. Complete recovery or only minimal neurologic deficits were demonstrated in five of the nine patients. Despite recanalization of the basilar artery, two patients had no major change in their neurologic function, and both ultimately had severe ataxia and were fully dependent on others. A cerebellar hemorrhage occurred in one patient but without clinical worsening. Two patients had a retroperitoneal hematoma. CONCLUSION: Intra-arterial thrombolysis with urokinase in acute basilar artery occlusion resulted in recanalization in seven of the nine patients (78%). Five of the nine patients recovered fully, including two patients who had had locked-in syndrome. In light of the devastating natural course of acute basilar artery occlusion, these initial results are encouraging and indicate that intra-arterial thrombolysis may be a useful emergency treatment, even in patients with prolonged symptoms of ischemia (up to 12 hours). PMID- 9374974 TI - Are coronary-care unit changes in therapy associated with improved survival of elderly patients with acute myocardial infarction? AB - OBJECTIVE: To determine whether changes in coronary-care unit therapy for elderly patients with acute myocardial infarction have been associated with improved survival. MATERIAL AND METHODS: We conducted a retrospective cohort analysis of all patients 70 years of age or older from Olmsted County, Minnesota, who were hospitalized in a coronary-care unit in this county for the treatment of acute myocardial infarction during one of three periods: 1976 through 1978, 1987 through 1989, and 1991. The effect of aspirin, heparin, beta-blockers, thrombolysis, percutaneous transluminal coronary angioplasty, and coronary artery bypass grafting on these elderly patients with acute myocardial infarction was assessed. RESULTS: Improvement in 30-day survival was significant for patients 80 years of age or older (45%, 69%, and 78% in 1976 through 1978, 1987 through 1989, and 1991, respectively; P = 0.01 for the trend) but not for patients 70 to 79 years of age (77%, 76%, and 81% for the three time periods, respectively; P = 0.65 for the trend). The opposite pattern was observed for survival in the period more than 30 days after the event. More intensive treatment in the hospital was associated with better 30-day survival (P < 0.0001). CONCLUSION: The improved survival of the elderly patients with acute myocardial infarction in these cohorts can be accounted for by changes in the therapy they received in the coronary-care units. PMID- 9374975 TI - Efficacy of deoxycholate amphotericin B and unilamellar liposomal amphotericin B in prophylaxis of experimental Aspergillus fumigatus endocarditis. AB - OBJECTIVE: To evaluate and compare in vivo the protective efficacy of unilamellar liposomal amphotericin B (L-AmB) with that of deoxycholate amphotericin B (D-AmB) in experimental endocarditis. MATERIAL AND METHODS: In the rabbit model of experimental Aspergillus fumigatus endocarditis, two doses of each antifungal agent (1.5 mg/kg each) were administered intravenously at 4 hours and at 30 minutes before challenge with an inoculum of A. fumigatus. Three days later, the animals were sacrificed, and the aortic vegetations were analyzed. RESULTS: All 19 animals that did not receive chemoprophylaxis acquired endocarditis. In contrast, endocarditis developed in 2 of 10 animals pretreated with D-AmB (P < 0.01) and 3 of 8 animals pretreated with L-AmB (P < 0.01). Both D-AmB and L-AmB prevented the development of endocarditis due to A. fumigatus and decreased the concentration of fungi in the aortic vegetations by more than 1 log10. CONCLUSION: In the rabbit experimental model of Aspergillus endocarditis, D-AmB and L-AmB were equally effective in reducing the incidence of the infection and the tissue burden of fungi. PMID- 9374976 TI - Giant cell granulomatous pulmonary and myocardial lesions in necrobiotic xanthogranuloma with paraproteinemia. AB - OBJECTIVE: To report three cases of pulmonary or myocardial disease (or both) and necrobiotic xanthogranuloma. MATERIAL AND METHODS: Giant cell granulomas of the lung and myocardium were demonstrated in three patients who had pulmonary and myocardial lesions of necrobiotic xanthogranuloma in conjunction with skin lesions, leukopenia, paraproteinemia, and complement deficiencies. The patients were two men who were 47 and 64 years of age and a 39-year-old woman. RESULTS: Biopsies of skin and visceral lesions showed asteroid and cytoplasmic inclusions. B-cell lymphoid nodules were found. In one of the male patients, a major clonal T cell receptor gene rearrangement was detected in the peripheral blood. Prednisone was ineffective in two of the patients. The other patient experienced regression of skin lesions and diminishment of a chest nodule after receiving alkylating agent therapy. CONCLUSION: Establishing the correct diagnosis is important, and apparently it is possible to establish the nature of the myocardial and pulmonary lesions with use of appropriate scans and by biopsy. Successful treatment of necrobiotic xanthogranuloma skin lesions with corticosteroids or alkylating agents (or both) implies that evolution of serious disease that compromises the heart and lungs could be controlled. PMID- 9374977 TI - Mitral regurgitation: a new clinical perspective. AB - Mitral regurgitation is a common valvular heart disease, particularly in the elderly population. The timing of surgical repair is controversial, but recent literature suggests a new clinical perspective on the management of this disease. Despite receiving medical treatment and having few initial symptoms, patients with mitral regurgitation due to flail leaflets have an excess mortality rate (6.3% per year) and high morbidity. Ten years after mitral regurgitation has been diagnosed, 90% of the patients have either died or undergone an operation. After surgical correction of mitral regurgitation, left ventricular dysfunction is a frequent complication and is the cause of excess heart failure and mortality. This complication is due to preoperative left ventricular dysfunction but is incompletely predictable with use of current methods. Conversely, considerable progress in surgery has resulted in an extremely low operative mortality rate (about 1% in patients younger than 75 years of age) and high feasibility of valve repair, even in patients with anterior leaflet prolapse. These facts have led to the new perspective that early surgical correction (before occurrence of overt symptoms or left ventricular dysfunction) should be considered when patients are diagnosed with severe mitral regurgitation. PMID- 9374978 TI - Pregnancy after pancreatic-renal transplantation because of diabetes. AB - In this article, we describe two pregnancies in the same patient after pancreatic renal transplantation. Severe, labile hypertension necessitated delivery at 35 weeks during the patient's first pregnancy and at 30 weeks (associated with renal graft obstruction) during her second pregnancy. Women with insulin-dependent diabetes mellitus who undergo pancreatic-renal transplantation can have a successful pregnancy if adequate multidisciplinary, specialized medical care is rendered. PMID- 9374979 TI - Giant cell arteritis manifesting as chronic cough and fever of unknown origin. AB - A 57-year-old white man sought medical attention because of chronic cough and fever of unknown origin. An extensive work-up over 4 weeks, including repeated blood cultures, chest roentgenograms, a gallium scan, and computed tomographic scans of the sinuses, chest, and abdomen, was nondiagnostic. The patient was referred to our institution for bronchoscopy. Further analysis of his history revealed that he had a headache in conjunction with the cough and an episode of a flashing color design in his left eye 1 week before assessment. The erythrocyte sedimentation rate was 115 mm in 1 hour. A biopsy of the temporal artery showed granulomatous inflammation of the vessel wall with multinucleated giant cells, histiocytes, lymphocytes, plasma cells, and few eosinophils. The multinucleated giant cells were closely related to the fragmented elastic lamina. Corticosteroid therapy resulted in prompt resolution of the chronic cough and fever. Giant cell arteritis should be considered in the differential diagnosis of chronic cough. PMID- 9374980 TI - Issues concerning androgen replacement therapy in postmenopausal women. AB - A decrease in blood androgen levels is well documented in women who experience natural or surgical menopause. This change may be associated with various negative effects on bone metabolism in addition to psychosocial and sexuality aspects of life. A review of published information on androgen replacement therapy shows that major benefits may be achieved; unfortunately, only minimal quality information is available to help clinicians make decisions about this type of therapy. In this review, we point out the potential benefits and risks to bone, lipid and carbohydrate metabolism, and sexuality; in addition, we discuss potential risks of neoplasms and virilizing somatic changes. Long-term, physiologic, and well-designed androgen replacement studies should be performed to obtain the knowledge needed to guide therapy in this important area. PMID- 9374981 TI - J. Erik Jorpes--pioneer in the identification and clinical applications of heparin. PMID- 9374982 TI - 28-year-old man with renal insufficiency and jaundice. PMID- 9374983 TI - The German health-care system. AB - The German health-care system is characterized by a statutory health insurance based on the principle of social solidarity. Nonprofit sickness funds and regional associations of physicians are the central components of the German system. The historical development of the system for more than 100 years has been characterized by negotiations, rather than confrontation, among physicians, patients, and insurance carriers. With the increasing sophistication of modern medicine, medical expenditure is rising, and great demands are facing the health care systems of the industrialized world. The hope is that the German system will be able to preserve the principle of solidarity and remain a one-tier health-care system rather than allow health care to be viewed as essentially a private consumption good, in which case availability and quality are allowed to vary with family income. As a means to achieve this goal, the autonomy of the sickness funds and regional associations of physicians will be increased substantially, and the governmental authority will be decreased. Strengthening of autonomy must be accompanied by incentives for self-responsibility and self-participation of Germany's citizens. PMID- 9374984 TI - Clinical outcome measures and rating scales in multiple sclerosis trials. AB - In this review, we analyzed clinical outcome measures used in multiple sclerosis (MS) clinical trials in which the primary goal is to slow or arrest progression of disease. In addition, we examined rating scales that quantify symptomatic complications of MS (for example, spasticity) and the current role of magnetic resonance imaging in MS treatment trials. Each proposed scale has advantages and deficiencies, and none meets all the criteria for an ideal outcome measure. The validity of trial design may be improved by using combinations of selected components of current scales as well as new instruments targeted to specific variables (such as motor strength). Symptom-specific rating scales are most appropriately used in trials of symptomatic therapeutic strategies for MS. Until serial magnetic resonance imaging changes are definitely known to predict long term impairment and disability in patients with MS, clinical outcome measures will remain the primary means of assessing therapeutic efficacy in phase III clinical trials. PMID- 9374985 TI - Value of magnetic resonance imaging in assessing efficacy in clinical trials of multiple sclerosis therapies. AB - Magnetic resonance imaging (MRI) has become an important technique for monitoring the effectiveness of putative treatments for multiple sclerosis (MS) because of its high sensitivity, objectivity, and noninvasive nature. Its importance as a surrogate measure of disease, however, is an issue that is more difficult to validate than might seem to be the case. In this review, we describe the role of MRI in the assessment of putative therapies for MS. New magnetic resonance techniques and methods of image analyses aimed at better demonstrating the nature and extent of disease are discussed, and the role of MRI in published MS therapeutic trials is examined. MRI is a frequently used secondary outcome measure for putative treatment strategies for MS. Although it is sensitive to changes in the inflammatory component of the MS disease process, poor correlation has been noted between MRI findings and long-term patient outcome. There is a widespread expectation that new magnetic resonance techniques--such as fluid attenuated inversion recovery, magnetization transfer imaging, and magnetic resonance spectroscopy--will ultimately be useful for characterization of pathologic changes within the MS lesion and more generally of the MS disease process. Whether magnetic resonance changes seen in experimental therapies predict the long-term clinical course of the disease remains to be determined. PMID- 9374986 TI - Stroke thrombolysis--growing pains. PMID- 9374987 TI - Enhanced sensitivity of the borreliacidal-antibody test. PMID- 9374988 TI - Contaminants in commercial preparations of melatonin. PMID- 9374989 TI - Pediatric oncology. Surgical and radiologic correlations. AB - Many aspects of surgical decision making related to the surgical evaluation and management of children with cancer depend on information gained from radiographic imaging and radiologic consultation. A brief review of the questions that surgeons ask the radiologist may aid the radiologist in focusing the consultation. PMID- 9374990 TI - Pediatric radiotherapy. An overview. AB - The use of RT in pediatric cancer has been virtually eliminated in certain diseases (NHL); greatly reduced in some (Wilms' tumor, ALL, neuroblastoma); and refined and modified in others (rhabdomyosarcoma, Ewing's sarcoma). At present, however, it seems clear that RT will continue to be an important modality (particularly in brain tumors) and a much greater understanding of its effects has been achieved and utilized. The knowledge of the occurrence of late effects and SMN in a child cured of cancer is continuing to modify initial treatment strategies: A classic example of such an effort is the common use of lower RT doses and nonalkylator-based chemotherapy in Hodgkin's disease. Further, the use of DNA testing in children may be able to identify the presence of germline RB and p53 mutations, which may identify a child at high risk for SMN, so that appropriate therapeutic modifications may be made. In addition, knowledge of these late consequences in children mandates that they be carefully monitored and closely followed, so that prompt and effective treatment can be administered to give them a better chance for a long and healthy life. PMID- 9374991 TI - Imaging modalities in pediatric oncology. AB - Many imaging modalities are available for the diagnosis, follow-up, and sometimes treatment of pediatric oncology diseases. The advantages and disadvantages, indications and contraindications, techniques, and patient preparations of the most commonly used modalities are discussed in this article. The role of sedation and the most widely used drugs are also discussed. PMID- 9374992 TI - Central nervous system tumors of childhood. AB - Primary tumors of the central nervous system are the most common solid tumors of childhood. Although numerous tumors of the brain and spine are common to both pediatric and adult population groups, there are many tumors unique to infancy and childhood. This article describes the characteristic locations, clinical presentations, and imaging features of these tumors. PMID- 9374993 TI - Neck masses in infants and children. AB - Neck masses, both inflammatory and tumoral, are common in infants and children, and most are benign. This article examines the imaging characteristics of various neck masses in infants and children. Routine radiographs, ultrasound, CT scan, MR imaging, and nuclear scintigraphy are discussed. PMID- 9374994 TI - Cardiopulmonary and thoracic tumors of childhood. AB - Cardiopulmonary and thoracic tumors in children are a diverse group of neoplasms. Unfortunately, presenting signs and symptoms are nonspecific. Imaging determines the anatomic site of origin, characterizes the mass, and defines its extent. This article reviews the appearance of cardiopulmonary and thoracic malignancies of childhood utilizing routine radiography, CT scan, MR imaging, and echocardiography. PMID- 9374995 TI - Gastrointestinal tumors of childhood. AB - Tumors of the gastrointestinal tract in children are divided into tumors involving the solid organs that bud from the gastrointestinal tract, principally the liver, and tumors intrinsic to the alimentary tract. This article presents a review of the current state of understanding of solid tissue tumors. The human genome project and better understanding of human genetics have led to remarkable changes in the classification and description of tumors of the alimentary tract. This article attempts to summarize these changes to a current classification of the gastrointestinal polyposis syndromes. PMID- 9374996 TI - Renal neoplasms of childhood. AB - Wilms' tumor is the most common childhood renal tumor. This article describes the epidemiology, histopathologic features, and clinical manifestations of Wilms' tumor along with the spectrum of imaging findings using different modalities. The distinguishing features of other renal tumors encountered in children, such as clear cell sarcoma, rhabdoid tumor, congenital mesoblastic nephroma, multilocular cystic renal tumor, renal cell carcinoma, and angiomyolipoma are also reviewed. PMID- 9374997 TI - Adrenal neoplasms in children. AB - Neuroblastoma is the most common extracranial neoplasm of childhood. Although it most commonly occurs in the adrenal gland, it may be found anywhere along the sympathetic chain. The characteristic clinical and imaging features of neuroblastoma are discussed in this article. Less common neoplasms of the adrenal gland, adenoma, adrenocortical carcinoma, and pheochromocytoma are also discussed. PMID- 9374998 TI - Pelvic tumors in childhood. AB - Pelvic neoplasms can arise from the genitourinary tract, gonads, or soft tissues. When a pelvic mass is detected on physical examination or a conventional radiographic study imaging evaluation is performed to characterize the lesion further and determine its site of origin and extent. Ultrasonography is used initially for the evaluation of most suspected lower genitourinary and testicular masses, because it does not use ionizing radiation. If the lesion is malignant, CT scan or MR imaging are warranted to detect the extent of pelvic invasion prior to surgery, chemotherapy, or radiation therapy. CT scan and MR imaging can also be helpful when sonography is suboptimal because of abundant bowel gas, a problem often encountered in evaluating the presacral space. CT scan and MR imaging are not degraded by bowel gas, and hence are most useful for evaluating a presacral mass When a presacral mass is suspected to be malignant, MR imaging is superior to CT scan to detect intraspinal invasion and soft tissue infiltration. PMID- 9375000 TI - Leukemia and lymphoma in childhood. AB - The leukemias and lymphomas together account for over 40% of the malignant disorders in childhood. Radiologists who deal with these patients must understand some aspects of the biology, natural history, and clinical manifestations of the disease in order to provide useful imaging consultative services. This article summarizes these issues briefly, gives an overview of the common imaging appearances, and recommends imaging studies to be utilized in the initial staging evaluation of newly presenting patients. PMID- 9374999 TI - Imaging pediatric bone sarcomas. Diagnosis and treatment-related issues. AB - The treatment of pediatric bone malignancies has undergone dramatic change in the past two decades. With the use of adjuvant chemotherapy, survival of patients with osteosarcoma and Ewing's sarcoma has greatly increased and most extremity lesions are now managed with an initial course of chemotherapy followed by limb sparing surgery rather than amputation. Radiologists are called on not only to help diagnose and stage these tumors, but also to assess their extent, to determine response to preoperative chemotherapy, and to monitor patients for postoperative complications and recurrent disease. This article discusses imaging solutions to clinical issues that arise during the care of these children. PMID- 9375001 TI - AIDS-related malignancies in pediatrics. AB - This article attempts to bring the reader up to date with the latest developments concerning AIDS-related malignancies in children. As these children live longer as a result of improved therapy, malignancies of the type described will become more common and wide-spread. PMID- 9375002 TI - Revelations of a captive: retroviral Qin and the oncogenicity of winged helix proteins. PMID- 9375003 TI - Characterisation of gamma herpesviruses in the horse by PCR. AB - A polymerase chain reaction (PCR) based on a combination of oligonucleotide primers selected using the octamer frequency disparity method with primers specific for EHV-5 (described by other authors) recognized all of a series of gamma herpesvirus field isolates. This PCR produced only three fragments: (1) one EHV-2-specific; (2) one EHV-5-specific; and (3) a fragment that occurred alone or in combination with the other two. Cloning and sequencing of four different isolates yielding only the last PCR product showed that this corresponds to a deletion/insertion mutant of EHV-2. The fact that this mutant was also plaque purified from a culture producing all three PCR fragments demonstrated that the virus producing this fragment was distinct from the other two and that this specific DNA fragment was not an artefact due to PCR amplification. These data show that equine gamma herpesviruses are genetically more heterogeneous than previously assumed. The PCR failed to directly detect gamma herpesviruses from the DNA extracted from the same starting material used for the isolation of gamma herpesvirus by cocultivation with indicator cells. This demonstrates that the most reliable method for detection of equine gamma herpesviruses is the cocultivation with indicator cells. PMID- 9375004 TI - Membrane fusion activity of Semliki Forest virus in a liposomal model system: specific inhibition by Zn2+ ions. AB - Semliki Forest virus (SFV) has been shown previously to fuse efficiently with cholesterol- and sphingolipid-containing liposomal model membranes in a low-pH dependent manner. Several steps can be distinguished in this process, including low-pH-induced irreversible binding of the virus to the liposomes, facilitated by target membrane cholesterol, and subsequent fusion of the viral membrane with the liposomal bilayer, specifically catalyzed by target membrane sphingolipid. Binding and fusion are mediated by the heterodimeric viral envelope glycoprotein E2/E1. At low pH the heterodimer dissociates, and the E1 monomers convert to a homotrimeric structure, the presumed fusion-active conformation of the viral spike. In this paper, we demonstrate that SFV-liposome fusion is specifically inhibited by Zn2+ ions. The inhibition is at the level of the fusion reaction itself, since virus-liposome binding was found to be unaffected. Zn2+ did not inhibit E2/E1 dissociation, but severely inhibited exposure of an acid-specific epitope on E1, E1 homotrimer formation, and acquisition of trypsin-resistance. It is concluded that virus--liposome binding solely requires low-pH-induced E2/E1 heterodimer dissociation, while fusion depends on further rearrangements in the E1 spike protein. As these rearrangements occur subsequent to the binding step, their precise course, including the formation of a fusion complex, may be influenced by interaction of E1 with target membrane lipids. PMID- 9375005 TI - The KSHV/HHV8-infected BCBL-1 lymphoma line causes tumors in SCID mice but fails to transmit virus to a human peripheral blood mononuclear cell graft. AB - The body-cavity-based lymphoma cell line BCBL-1, which is infected with Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8, was injected alone or with human peripheral blood mononuclear cells into SCID mice. Immunoblastic lymphomas developed at or near the site of injection. The lymphomas appeared to derive exclusively from the injected BCBL-1 cells and not from the injected human PBMC. The tumors elicited a marked murine angiogenic response, but known angiogenic cytokines were not detected in BCBL-1 cells. Transfer of BCBL-1 cells to SCID mice may represent an in vivo model for the study of KSHV/HHV8-stimulated angiogenesis. PMID- 9375006 TI - Ultrastructure and localization of E proteins in cultured neuron cells infected with Japanese encephalitis virus. AB - A unique structure and in situ localization of E proteins were demonstrated in cultured neurons infected with neurovirulent and aneurovirulent strains of local Japanese encephalitis virus (JEV). Dilated rough endoplasmic reticulum (rER) containing smooth membrane structures (SMS) was continuous with the outer membrane of the nuclear envelope. These membranes were found to be connected to unique dense bodies, membrane vesicle structures (MVS). The de novo formation of SMS, annulate lamellae, and the appearance of MVS indicated proliferation of the membranous system in response to JEV infection. E proteins were possibly assembled in the virions in the nuclear envelope or rER or on the plasma membrane. The interconnections between MVS, rER, and the nuclear envelope and immunogold labeling of E proteins on the MVS provided strong evidence that MVS serve as a reservoir of JEV components during virus assembly. PMID- 9375007 TI - Characterization of events during the late stages of HPV16 infection in vivo using high-affinity synthetic Fabs to E4. AB - HPV late gene expression is initiated as an infected basal cell migrates through the differentiating layers of the epidermis, resulting in the onset of vegetative viral DNA replication and the expression of viral late proteins. We have used a large synthetic immunoglobulin library displayed on phage (diversity 6.5 x 10(10) phage) to isolate three Fabs (TVG405, 406, and 407) which recognize distinct epitopes on the E4 late protein of HPV16. A C-terminal monoclonal (TVG404) was generated by hybridoma technology, and N-terminal polyclonal antiserum was prepared by peptide immunization (alpha N-term). The most potent antibody (TVG405) had an affinity for E4 of approximately 1.0 nM. All antibodies recognized the protein in paraffin-embedded archival material, allowing us to map events in the late stages of virus infection. Expression of E4 in vivo does not coincide with synthesis of the major virus coat protein L1, but precedes it by 1 or 2 cell layers in premalignant lesions caused by HPV16 and by up to 20 cell layers in HPV63-induced warts. In higher grade lesions associated with HPV16, E4 is produced in the absence of L1. By contrast, vegetative viral DNA replication and E4 expression correlate exactly and in some lesions begin as the infected epithelial cell leaves the basal layer. Differentiation markers such as filaggrin, loricrin, and certain keratins are not detectable in E4-positive cells, and nuclear degeneration is delayed. HPV16 E4 has a filamentous distribution in the lower epithelial layers, but associates with solitary perinuclear structures in more differentiated cells. Antibodies to the N-terminus of the protein stained these structures poorly. Our findings are compatible with a role for the HPV16 E4 protein in vegetative DNA replication or in modifying the phenotype of the infected cell to favor virus synthesis or virus release. The Fabs will be of value in the evaluation of model systems for mimicking HPV infection in vitro. PMID- 9375008 TI - Acyclovir blocks cytokine gene expression in trigeminal ganglia latently infected with herpes simplex virus type 1. AB - We have previously found that interleukin (IL)-2, IL-10, interferon (IFN)-gamma, RANTES, and tumor necrosis factor (TNF)-alpha mRNA transcription remain elevated in the trigeminal ganglia (TG) of herpes simplex virus type 1 (HSV-1) latently infected mice up to 120 days postinoculation (p.i.). To determine if this phenomenon was dependent on HSV-1 DNA replication after the establishment of latency (i.e., reactivation), cytokine gene expression was compared in TG of acyclovir-treated and untreated latently infected mice. Oral acyclovir treatment (begun 16 days p.i.) had no effect on serum levels of total anti-HSV-1 antibodies. However, there was a significant reduction in the titer of antibody specific for glycoprotein D and glycoprotein B but not glycoprotein H/L 120 days PI in the acyclovir-treated compared to vehicle-treated mice. These differences were not significant at earlier time points (i.e., days 34 and 60 p.i.). Consistent with these findings, acyclovir had no effect on cytokine gene expression in latently infected TG 35 and 60 days p.i. However, 120 days p.i., IFN-gamma and TNF-alpha mRNA were approaching baseline levels in TG of acyclovir treated mice, but remained significantly elevated in untreated controls (i.e., IFN-gamma mRNA levels were sixfold higher in TG of untreated mice). Therefore, viral DNA replication appears to provide an antigenic stimulus for persistent cytokine gene expression in latently infected TG. PMID- 9375009 TI - Phylogenetic relationship of the complete Rauscher murine leukemia virus genome with other murine leukemia virus genomes. AB - We report the complete nucleotide sequence of the genome of Rauscher murine leukemia virus (R-MuLV), the replication-competent helper virus present in the Rauscher virus complex, and its phylogenetic relationship with other murine leukemia virus genomes. An overall sequence identity of 97.6% was found between R MuLV and the Friend helper virus (F-MuLV), and the two viruses were closely related on the phylogenetic trees constructed from either gag, pol, or env sequences. Moloney murine leukemia virus (Mo-MuLV) was the next closest relative to R-MuLV and F-MuLV on all trees, followed by Akv and radiation leukemia virus (RadLV). The most distantly related helper virus was Hortulanus murine leukemia virus (Ho-MuLV). Interestingly, Cas-Br-E branched with Mo-MuLV on the gag and pol trees, whereas on the env tree, it revealed the highest degree of relatedness to Ho-MuLV, possibly due to an ancient recombination with an Ho-MuLV ancestor. In summary, a phylogenetic analysis involving various MuLVs has been performed, in which the postulated close relationship between R-MuLV and F-MuLV has been confirmed, consistent with the pathobiology of the two viruses. PMID- 9375010 TI - Antigen specificity of CD4 T cell response in the central nervous system of mice infected with mouse hepatitis virus. AB - Previously, we showed that the transmembrane (M) and surface (S) glycoproteins were recognized by splenic CD4 T lymphocytes harvested from mice infected intraperitoneally with mouse hepatitis virus, strain JHM (MHV-JHM), whereas only the S protein was recognized by splenocytes derived from mice with MHV-induced chronic demyelination. From these results, it could not be determined which proteins were recognized by T cells localized in the infected central nervous system (CNS). Herein, we show that CD4 T cells responding to both the M and S proteins can be detected in the CNS of mice with either acute encephalitis or the chronic demyelinating disease. As part of these analyses, two CD4 T cell epitope regions encompassing residues 328-347 and 358-377 within the S protein were identified. Both epitopes, as well as a previously identified M-specific epitope, were recognized by the CNS-derived lymphocytes. Finally, viral RNA harvested from mice with chronic demyelination was analyzed for mutations in the S specific CD4 T cell epitopes since changes resulting in escape from CD8 T cell surveillance were previously identified in these samples. A mutation in epitope region S(328 347) (ala to thr at position 337) was detected in a minority of samples but this change did not abrogate recognition of the epitope and therefore was unlikely to contribute to virus persistence. In conclusion, these studies identify epitopes recognized by MHV-specific CD4 T cells in the infected CNS and show that these cells are preferentially located at the site of infection in mice with clinical disease. PMID- 9375011 TI - Crystals of Rous sarcoma virus capsid protein show a helical arrangement of protein subunits. AB - Crystals of Rous sarcoma virus (RSV) capsid protein diffract X rays to 3.5 A resolution and belong to the monoclinic space group C2 with unit cell parameters a = 374.4 A, b = 128.1 A, c = 200.2 A, and beta = 121.8 degrees. One asymmetric unit of the crystal may contain between 28 and 35 molecules, based on reasonable crystal density assumptions. A self-rotation function and Patterson synthesis suggest that RSV capsid protein crystallizes as a helical array. The determinants of the viral particle morphology are not encoded in the capsid alone. The assembly of a helical array in the crystal reflects the absence of any conformational switching. However, it is expected that the subunit interactions seen in the crystal will be preferred and will relate to those found in the immature or mature virion. PMID- 9375012 TI - Frequency of memory cytotoxic T lymphocytes to equine infectious anemia virus proteins in blood from carrier horses. AB - Horses with equine infectious anemia virus (EIAV) have episodes of viremia and disease; however, most eventually become inapparent carriers. A possible mechanism of control is cytotoxic T lymphocytes (CTL). To evaluate CTL in inapparent carriers with low viral loads, peripheral blood mononuclear cells (PBMC) were stimulated in vitro with autologous EIAV-infected PBMC and human IL-2 to detect memory CTL (CTLm). In initial studies, three carriers had CTLm and one of these had low-level effector CTL (CTLe). The CTLm were restricted by equine lymphocyte alloantigen-A (ELA-A) locus encoded MHC class I molecules on autologous equine kidney (EK) target cells. In addition, EK cells did not express MHC class II molecules. The CTLm frequency in PBMC from five inapparent carriers infected for 22 to 50 months was determined by limiting dilution analysis. PBMC were diluted, stimulated, and tested on EK cell targets infected with EIAV and recombinant vaccinia viruses expressing EIAV Env or Gag/Pr proteins. All five carriers had CTLm to EIAV-infected targets, while four had CTLm to targets expressing Env and four had CTLm to targets expressing Gag/Pr proteins. The CTLm frequency range was 60 to 468 per 10(6) PBMC to EIAV-infected targets, 4 to 286 to Env-expressing targets, and 25 to 190 to Gag/Pr-expressing targets. These results should facilitate the identification of epitopes recognized by predominant CTLm from horses controlling a lentivirus infection. PMID- 9375013 TI - In vitro infection and replication of hepatitis E virus in primary cynomolgus macaque hepatocytes. AB - An in vitro model was developed to replicate hepatitis E virus (HEV) in normal primary cynomolgus macaque hepatocytes using a hormonally defined, serum-free medium formulation. Primary hepatocytes were infected in tissue culture following isolation by collagenase treatment of liver wedge biopsy material. Viral replication was monitored by a highly strand-specific reverse transcription polymerase chain reaction (RT-PCR) assay, which could detect the positive- and negative-strands of HEV RNA independently in a sensitive and specific manner. Several infectious HEV (Burma strain) inocula were titered by this RT-PCR assay, and a minimum effective infectious dose was determined. Appearance of newly replicated virus was demonstrated by detection of both strands of HEV RNA in experimentally infected hepatocytes as well as the genomic positive-strand viral RNA in the culture medium. Infectivity of the virus particles present in the media was confirmed by serial passage and replication of the virus in culture. Using this in vitro infection system, a neutralization assay was developed to assess the ability of anti-HEV antibodies to block virus infection of liver cells. Results presented in this report represent the first in vitro demonstration of a neutralizing anti-HEV antibody directed against the ORF2 encoded putative capsid protein. PMID- 9375015 TI - Laguna Negra virus associated with HPS in western Paraguay and Bolivia. AB - A large outbreak of hantavirus pulmonary syndrome (HPS) recently occurred in the Chaco region of Paraguay. Using PCR approaches, partial virus genome sequences were obtained from 5 human sera, and spleens from 5 Calomys laucha rodents from the outbreak area. Genetic analysis revealed a newly discovered hantavirus, Laguna Negra (LN) virus, to be associated with the HPS outbreak and established a direct genetic link between the virus detected in the HPS cases and in the C. laucha rodents, implicating them as the primary rodent reservoir for LN virus in Paraguay. Virus isolates were obtained from two C. laucha, and represent the first successful isolation of a pathogenic South American hantavirus. Analysis of the prototype LN virus entire S and M and partial L segment nucleotide and deduced amino acid sequences showed that this virus is unique among the Sigmodontinae-borne clade of hantaviruses. Analysis of PCR fragments amplified from a serum sample from a Chilean HPS patient, who had recently traveled extensively in Bolivia (where C. laucha are known to occur), revealed an LN virus variant that was approximately 15% different at the nucleotide level and identical at the deduced amino acid level relative to the Paraguayan LN virus. These data suggest that LN virus may cause HPS in several countries in this geographic region. PMID- 9375014 TI - Basic amino acid residues at the carboxy-terminal eleven amino acid region of the phosphoprotein (P) are required for transcription but not for replication of vesicular stomatitis virus genome RNA. AB - The phosphoprotein (P) of vesicular stomatitis virus (VSV) serotypes New Jersey [P(NJ)] and Indiana [P(I)] contains a highly conserved carboxy-terminal domain which is required for binding to the cognate N-RNA template as well as to form a soluble complex with the nucleocapsid protein N in vivo. We have shown that the deletion of 11 amino acids from the C terminal end of the P(I) protein abolishes both the template binding and the complex forming activity with the N protein. Within this region, there are conserved basic amino acid residues (R260 and K262) that are potential candidates for such interactions. We have generated mutant P proteins by substitution of these basic amino acid residues with alanine and studied their role in both transcription and replication. We have found that the R260A mutant failed to bind to the N-RNA template, whereas the K262A mutant bound efficiently as the wild-type protein. The R260A mutant, as expected, was unable to support mRNA synthesis in vitro in a transcription reconstitution reaction as well as transcription in vivo of a minigenome using a reverse genetic approach. However, the K262A mutant supported low level of transcription (12%) both in vitro and in vivo, suggesting that direct template binding of P protein through the C-terminal domain is necessary but not sufficient for optimal transcription. Using a two-hybrid system we have also shown that both R260A and K262A mutants interact inefficiently with the L protein, suggesting further that the two point mutants display differential phenotype with respect to binding to the template. In addition, both R260A and K262A mutants were shown to interact efficiently with the N protein in vivo, indicating that these mutants form N-P complexes which are presumably required for replication. This contention is further supported by the demonstration that these mutants support efficient replication of a DI RNA in vivo. Since the transcription defective P mutants can support efficient replication, we propose that the transcriptase and the replicase are composed of two distinct complexes containing (L-P2-3) and L-(N-P), respectively. PMID- 9375017 TI - Envelope glycoprotein nucleotide sequence and genetic characterization of North American ovine lentiviruses. AB - Ovine lentiviruses (OvLV) resemble human immunodeficiency viruses in genomic organization, viral heterogeneity, and spectrum of cytophenotypic expression. To gain a better understanding of the relationship of North American OvLV isolates with other characterized OvLV strains, the complete DNA nucleotide sequence of the env region of a highly lytic (rapid/high) OvLV strain (85/34) was determined and compared with the sequence of amplicons within env of three other OvLV strains of varying cytophenotype and isolated from the same flock of sheep. LTR and pol regions also were compared among these strains. The env region of 85/34 was 986 codons in length and the reported nucleotide sequence showed features shared by other OvLV including heavy glycosylation and conserved and hypervariable regions within the surface membrane protein region. Phylogenetic analyses of regions within LTR, reverse transcriptase, and env grouped the four virus strains together and similar to the maedi-visna OvLV strains, including visna virus, South African ovine maedi visna virus, and EV1 (British OvLV isolate), but they were distinct from caprine arthritis encephalitis virus. PMID- 9375016 TI - The cysteine residues of the M2 protein are not required for influenza A virus replication. AB - The M2 protein of influenza A virus functions as an ion channel. It contains three cysteine residues: cysteines 17 and 19, which form disulfide bonds in the ectodomain, and cysteine 50 which is acylated. To understand the role of these cysteine residues in virus replication, we used reverse genetics to create influenza viruses in which the individual cysteines were mutated and a virus in which all three cysteines were changed to serine. The M2 cysteine mutants that lacked either of the cysteine residues in the ectodomain and the mutant that lacked all three residues had appreciably lower amounts of M2 oligomers than did the wild-type virus when examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. None of the mutants, however, were defective in replication, either in vitro or in ferrets and mice. These findings demonstrate that noncovalent interactions are sufficient for the M2 protein to form functional oligomers for virus replication and that its cysteine residues are dispensable for influenza virus replication in vitro and in vivo. PMID- 9375018 TI - The complete nucleotide sequence of the egg drop syndrome virus: an intermediate between mastadenoviruses and aviadenoviruses. AB - The complete nucleotide sequence of an avian adenovirus, the egg drop syndrome (EDS) virus, was determined. The total genome length is 33,213 nucleotides, resulting in a molecular weight of 21.9 x 10(6). The GC content is only 42.5%. Between map units 3.5 and 76.9, the distribution of open reading frames with homology to known genes is similar to that reported for other mammalian and avian adenoviruses. However, no homologies to adenovirus genes such as E1A, pIX, pV, and E3 could be found. Outside this region, several open reading frames were identified without any obvious homology to known adenovirus proteins. In the region organized similarly as other adenoviral genomes, most homologies were found to an ovine adenovirus (OAV strain 287). The highest level of amino acid identity was found for the hexon proteins of EDS and OAV. The virus-associated RNA (VA RNA) was identified thanks to the homology with the VA RNA of fowl adenovirus serotype 1 (FAV1). Similarities with FAV1 were also found in the fiber protein. Our results demonstrate that the avian EDS virus represents an intermediate between mammalian and avian adenoviruses. The nucleotide sequence and genomic organization of the EDS virus reflect the heterogeneity of the aviadenovirus genus and the Adenoviridae family. PMID- 9375019 TI - Infection of cats by injection with DNA of a feline immunodeficiency virus molecular clone. AB - Establishment of infection of animals with a viral clone will be important for investigating viral determinants of pathogenesis and monitoring sequence changes in the viral genome in vivo and may find utility as a means of immunization with live-attenuated virus. To test the efficiency of intramuscular (i.m.) injection of cloned proviral plasmid DNA for establishing feline immunodeficiency virus (FIV) infection in specific pathogen-free (SPF) cats, groups of cats were inoculated by the i.m. route with 300, 100, or 30 micrograms of plasmid DNA containing the infectious molecular clone, FIV-pPPR. A fourth group of cats was inoculated intradermally with 30 micrograms of FIV-pPPR plasmid DNA. For comparison, a fifth group received 10(3) TCID50 of a live virus stock of FIV-pPPR by intraperitoneal inoculation. Inoculation by i.m. injection with 100 to 300 micrograms of infectious FIV-pPPR proviral DNA produced infection detectable by both antiviral antibody and virus isolation from peripheral blood mononuclear cells. Inoculation by i.m. injection with 30 micrograms of proviral DNA resulted in infection in two of three inoculated cats. Intradermal injection with 30 micrograms of proviral DNA induced infection in one of three cats. Induction of antiviral antibody and viremia was delayed in cats inoculated with 30 micrograms compared to cats inoculated with either 100 or 300 micrograms of proviral DNA. This study indicates that cloned FIV proviral DNA may replace infectious virion preparations as inocula for pathogenesis and immunization studies. PMID- 9375020 TI - Identification of a MMTV insertion mutation within the coding region of the Fgf-3 protooncogene. AB - The Fgf-3 protooncogene (previously called int-2) is a target of proviral insertion mutations in mammary tumors induced by the mouse mammary tumor virus (MMTV). These insertion mutations result in the transcriptional activation of Fgf 3, which is not normally expressed in the adult mammary gland. Previous mapping studies of numerous Fgf-3 insertion mutations have failed to reveal any provirus integrations within the gene coding region. This finding is consistent with the hypothesis that oncogenesis occurs in this system as a consequence of up regulation of Fgf-3 transcription, rather than from alterations of the gene product. During an analysis of a new cohort of tumors from the WXG-2 mouse strain, a breast tumor was identified which had a MMTV provirus integrated 24 bp upstream of the Fgf-3 stop codon. This insertion mutation generated a fusion transcript which was readily detectable in tumor RNA by RT-PCR. The predicted protein product of this fusion transcript is missing 8 aa of native sequence and contains an additional 8 aa of cryptic MMTV-encoded sequence. These data document the first exception to the generalization that the Fgf-3 coding region is not disrupted by MMTV insertion mutation. PMID- 9375022 TI - E2F transcription factor action, regulation and possible role in human cancer. AB - E2F transcription factors regulate expression of a panel of cellular genes that control cellular DNA synthesis and proliferation, either by activating or repressing their transcription, largely in a cell cycle-dependent manner. The ability of E2F proteins to regulate expression of these target genes is, in turn, regulated by other cellular proteins that are important for normal control of cell cycle progression. Together, E2F proteins, their target genes, and the proteins that regulate E2F activity comprise a genetic pathway that is probably the most, frequently altered pathway in human cancer. This review examines this genetic pathway and focuses on the role of E2F proteins in its function. Specifically, the target genes regulated by E2F, the likely mechanisms by which activation and repression of target gene transcription is achieved, and the regulation of E2F activity by other proteins in the cell, are discussed. PMID- 9375023 TI - Immunoreactivity to MIB-1 in breast cancer: methodological assessment and comparison with other proliferation indices. AB - The recent availability of the monoclonal antibody MIB-1 (which is able to detect the human nuclear cell proliferation-associated antigen Ki-67 even on formalin fixed, paraffin-embedded sections, microwave-treated and routinely processed for immunohistochemistry) could open new avenues for validation of the clinical role of tumour cell proliferation on large, consecutive and unselected series of human tumours. However, the routine use of such a marker requires a methodological standardization as well as the comparative assessment of some technical and biological aspects. The MIB-1 index was determined in parallel samples from 50 consecutive invasive breast carcinomas processed with different fixatives for different times. The median values of MIB-1 indices following 2, 6 and 24 h of formalin fixation were similar (29.4%, 30.6% and 29.7%, respectively) and consistent with those reported in the literature; squared linear regression coefficients were 0.99. The median values of MIB-1 indices were markedly lower in Bouin-fixed, paraffin embedded, and in frozen samples (20.0% and 19.8%, respectively), with a poor correlation coefficient with the values detected following formalin fixation (R2 = 0.456). Moderate and poor correlations were observed between Ki-67 index and MIB-1 detected on frozen (rs, 0.78) or formalin fixed, paraffin-embedded samples (rs, 0.47) and a minimal concordance was observed between TLI and MIB-1 or Ki-67 (rs, 0.25 and 0.22, respectively). Our results indicate interference of the fixative type on immunoreactivity to MIB-1 and also suggest that Ki-67 and MIB-1 reacted with different epitopes of the same antigen. PMID- 9375025 TI - Prolactin receptor expression by splenocytes from rats in various hormonal states. AB - Prolactin (PRL) is mitogenic for lymphocytes in vitro, but the responsiveness of lymphocytes depends on the in vivo hormonal status of the rats from which the cells were obtained. Lymphocytes from ovariectomized (OVX) rats, but not from rats in oestrus or from male rats, respond to prolactin; administration of oestradiol to OVX rats diminishes the response. In order to determine if a correlation exists between lymphocyte responsiveness to prolactin and levels of cell surface prolactin receptors (PRL-R) expression, the percentage of splenocytes and each splenocyte subpopulation expressing surface PRL-R from rats of various hormonal states (OVX, oestradiol-injected OVX, oestrus and male) was analysed by single-colour and dual-colour flow cytometric analysis. We found that approximately 20% of splenocytes expressed surface PRL-R regardless of hormonal states (n = 16). The majority (85%) of PRL-R positive splenocytes were B lymphocytes whereas 11.1% and 4.8% of splenocytes expressing the PRL-R were CD4 positive T-helper (TH) and CD8 positive T-cytotoxic (TC) lymphocytes, respectively. B lymphocytes also stained more brightly than T lymphocytes. This distribution of PRL-R expression did not show significant alterations on total splenocytes or TH and TC lymphocytes during various hormonal stages. However, the percentage of PRL-R-positive B lymphocytes increased markedly in OVX rats (twofold), compared to rats at oestrus. In summary, no correlation was found between the responsiveness to prolactin as a mitogen and levels of PRL-R expression by lymphocytes from rats at different hormonal states. This result suggests that sex steroid hormones may control prolactin responsiveness of lymphocytes by affecting the signal transduction pathway through PRL-R rather than by altering the level of the cell surface receptor expression. PMID- 9375024 TI - 3H-thymidine labelling index (TLI) as a marker of tumour growth heterogeneity: evaluation in human solid carcinomas. AB - Many studies deal with the analysis of cell kinetic, cytogenetic, biochemical and molecular cell biology parameters to identify prognostic factors relating to tumour growth but all methods use only a small part of the total tumour mass. This study is devoted to the analysis of the heterogeneity of the growth of human solid tumours assaying proliferative activity by means of 3H-thymidine labelling index (TLI) in a fixed number of samples collected in different areas of the lesion (larynx and colon cancers), or in different lesions of the same subject (breast and bladder cancers). Each sample (at the macroscopic level) was divided into small fragments (at the microscopic level) and proliferative activity was determined. The analysis of variance for hierarchical designs demonstrated that in all cases a high component of the variance is attributable to the subjects and to the fragments whereas the variance attributable to the different areas is very low. The heterogeneity of proliferative activity displays a higher focal variability among the fragments (microscopic level) compared with that among areas (macroscopic level) within subjects, provided an adequate number of fragments and cells are counted. In multiple synchronous carcinoma of the bladder the wide variability of proliferation among the single lesions demonstrated that it is necessary to analyse all the tumours in a subject because each one is characterized by a different cell growth potential. PMID- 9375026 TI - Laser scanning cytometry (LCS) allows detailed analysis of the cell cycle in PI stained human fibroblasts (TIG-7). AB - We have demonstrated a method for the in situ determination of the cell cycle phases of TIG-7 fibroblasts using a laser scanning cytometer (LSC) which has not only a function equivalent to flow cytometry (FCM) but also has a capability unique in itself. LSC allows a more detailed analysis of the cell cycle in cells stained with propidium iodide (PI) than FCM. With LSC it is possible to discriminate between mitotic cells and G2 cells, between post-mitotic cells and G1 cells, and between quiescent cells and cycling cells in a PI fluorescence peak (chromatin condensation) vs. fluorescence value (DNA content) cytogram for cells stained with PI. These were amply confirmed by experiments using colcemid and adriamycin. We were able to identify at least six cell subpopulations for PI stained cells using LSC; namely G1, S, G2, M, postmitotic and quiescent cell populations. LSC analysis facilitates the monitoring of effects of drugs on the cell cycle. PMID- 9375027 TI - Effect of sodium butyrate on human breast cancer cell lines. AB - We have investigated the effects exerted by sodium butyrate (NaBu) on the growth and cell cycle perturbations of four human breast cancer cell lines (MCF7, T47D, MDA-MB231 and BT20) with different steroid receptor profiles. Moreover, since one of the supposed mechanisms of action for NaBu activity involves the induction of apoptosis, we have studied the effects of NaBu on DNA fragmentation by agarose gel electrophoresis and flow cytometry. In all investigated cell lines, NaBu exerted a time- and dose-dependent inhibition of growth and caused a maximum inhibitory effect (85% to 90%) at the concentration of 2.5 mM. The inhibition was already evident after 3 days of treatment. The antiproliferative effect of NaBu was associated with a persistent block of cells in the G2M phase. The block was associated with apoptosis only in oestrogen-receptor positive cell lines. The inhibiting effect of NaBu in hormone-dependent and independent cell lines and its ability to induce apoptosis through a cell cycle perturbation in hormone dependent cell lines may have important implications in the treatment of human tumours including breast cancer. PMID- 9375028 TI - The effects of irradiation at different times of the day on rat intestinal goblet cells. AB - Quantitative changes in jejunal goblet cells were studied in control and whole body irradiated rats using PAS-Alcian blue staining of crypt sections. A circadian dependence was observed when control animals were killed at different times during the light/dark cycle. Irradiation with 3 Gy produced a 2-3-fold increase within 36 h in goblet cells relative to controls, followed by a reduction to very low levels. There was a return to pre-treatment levels later than was observed for the columnar cells. The present results on the pattern of response of goblet cells and those of brush border enzyme activity are consistent with the hypothesis that ionizing radiation can influence differentiation. In fact during the first hours after irradiation an early induction of differentiation is evident while during the early repopulation phase columnar cells prevailed relative to the goblet cells. Only at later times were normal differentiation patterns seen. Groups of animals exposed to the same dose of radiation at different times of the day showed similar general patterns of behaviour even if the group irradiated at midnight showed a more marked and longer lasting injury. PMID- 9375029 TI - A mathematical model of the regulation of the G1 phase of Rb+/+ and Rb-/- mouse embryonic fibroblasts and an osteosarcoma cell line. AB - A mathematical model integrating the roles of cyclin D, cdk4, cyclin E, cdk2, E2F and RB in control of the G1 phase of the cell cycle is described. Experimental results described with murine embryo fibroblasts (MEFs), either Rb+/+ or Rb-/-, and with the RB-deficient osteosarcoma cell line, Saos-2, served as the basis for the formulation of this mathematical model. A model employing the known interactions of these six proteins does not reproduce the experimental observations described in the MEFs. The appropriate modelling of G1 requires the inclusion of a sensing mechanism which adjusts the activity of cyclin E/cdk2 in response to both RB concentration and growth factors. Incorporation of this sensing mechanism into the model allows it to reproduce most of the experimental results observed in Saos-2 cells, Rb-/- MEFS, and Rb+/+ MEFs. The model also makes specific predictions which have not been tested experimentally. PMID- 9375030 TI - A controversial issue: could a watch-and-wait policy for patients with non Hodgkin's lymphoma clinical stage I or IE with no lymphoma left following diagnostic surgery be justified? Results of a single centre study. AB - BACKGROUND: A subset of patients with non-Hodgkin's lymphoma (NHL) with clinical stage I or IE at presentation is left without other NHL localizations following surgery performed for diagnostic histology, and thus without any target lesion to judge the immediate effectiveness of immediately applied additional treatment modalities. MATERIAL AND METHODS: Since 1988 we have adopted in this single centre, prospective non-randomized study, a watch-and-wait policy for such patients, who in addition had to have non-bulky disease, normal LDH levels, no 'B' symptoms and no Burkitt, lymphoblastic and cutaneous T-cell histology. Up to 1993 we have observed 50 consecutive cases. Patients were regularly followed with the endpoint to determine the relapse-free interval and overall survival. NHL relapses were treated, either with locoregional radiotherapy, or with chemotherapy, or both. RESULTS: The median observation time is at the moment 53.5+ months (range 6-106+). The initial NHL localizations were: a solitary cervical or auxillary lymph node in 18 patients, inguinal or scarpal lymph node in eight, tonsil in 12 and skin/subcutis in 12 (B-cell NHL only for skin/subcutis). Nine patients had low, 15 intermediate, and 26 high-grade histology. Within the observation period NHL relapses occurred in 10/50 patients (20 per cent). At the moment 46/50 patients (92 per cent) are alive and NHL free. The estimated 9-year freedom from relapse is 79 per cent and overall survival 92 per cent, and for 41 patients with intermediate/high-grade histologies 80 per cent and 95 per cent respectively. CONCLUSION: It seems that a proportion of the very selected subgroup of patients with stage I of IE NHL and absolutely no NHL left following diagnostic surgery, with additional criteria as described in this study can achieve a substantial freedom from relapse and overall survival rate without immediate additional therapeutic procedures following diagnosis of NHL, but no prognostic factors predicting this outcome seem yet available. PMID- 9375031 TI - Molecular detection of a B cell clone in a case of PTCL in the absence of T cell clonality. AB - In this paper we document a case of peripheral T cell lymphoma (PTCL) that exhibited variable T cell histology at presentation and follow-up. Southern blot analysis for T cell receptor (TCR) and immunoglobulin (Ig) receptor gene rearrangements failed to reveal clonal T or B cell populations. TCR gamma (TCRG) and beta (TCRB) chain gene polymerase chain reaction (PCR) amplification of DNA isolated from biopsies was also consistent with polyclonal T cell populations, however Ig PCR revealed clonal Ig rearrangements in follow-up biopsies but not in the presentation biopsy. There was no histological evidence for a neoplastic B cell population in these biopsies although occasional EB virus positive blasts were present. The significance of a cryptic B cell clone is unknown but suggests a relationship with the proliferating polyclonal T cells in this case of PTCL. These data reflect the complexity of PTCL with implications for treatment and patient management. PMID- 9375032 TI - Natural killer cell lymphoma/leukemia: pathology and treatment. AB - Malignancies arising from cells of putative natural killer (NK) cell origin have increasingly been recognized as distinct clinicopathological entities. These malignancies are marked by tumour cells with NK cell characteristics, including the immunophenotype of CD2+, surface CD3-, cytoplasmic CD3 epsilon+, CD7 +/-, and CD56+, and the genotype of germline T cell receptor gene. A consistent association with monoclonal Epstein-Barr virus infection in the tumour cell has been observed. These tumours are now regarded as putative NK cell lymphoma/leukemia. Pathologically, tumour cells show variable cytological appearances, with frequent angiocentricity and angioinvasion, associated with zonal necrosis. Clinically, most cases occur in the nasal area and upper aerodigestive tract. However, occurrence in non-nasal sites such as the skin, gastrointestinal tract and testis is also observed. A particularly aggressive form of NK lymphoma/leukemia presents fulminantly as disseminated disease sometimes with a leukemic phase. All types of NK lymphoma/leukemia have an extremely poor prognosis with a median survival of less than a year. New modalities of treatment, including the use of high dose chemotherapy and stem cell rescue may be needed to improve treatment outcome. PMID- 9375033 TI - Decreased expression of bcl-2 (p26) in CD8(+) lymphocytes of patients with T-cell lymphoproliferative disorders of large granular lymphocytes. AB - The bcl-2 oncogene has been involved in the genesis of various B-cell neoplasms by means of encoding for p26, an apoptosis suppressor oncoprotein. The expression of p26 in lymphoproliferative disorders of large granular lymphocytes (LDLGL), a group of diseases whose mechanism leading to lymphocyte expansion is not yet clear, was not previously characterized. In order to further understand the biology of LDLGL, we compared the expression of p26 in CD8(+) lymphocytes of patients with CD3(+) LDLGL with that observed in normal individuals, patients with viral infection and patients with CD4(+) lymphoid neoplasms. We observed that upregulation of bcl-2 expression is not involved in the genesis of lymphocyte expansion in CD3(+) LDLGL. By contrast, when compared to normal peripheral blood counterparts, CD8(+, bright) lymphocytes of patients with LDLGL express low levels of p26 whereas CD8(+, dim) lymphocytes express normal or only slightly reduced levels of this oncoprotein. A similar pattern of expression of p26 was found in situations in which CD8(+) lymphocytes represent reactive activated cells. PMID- 9375034 TI - Hematological features and treatment outcome in acute myeloid leukemia with t(8;21). AB - We analyzed the hematological features and treatment outcome in 18 patients with t(8;21) acute myeloid leukemia (AML) diagnosed in Queen Mary Hospital, Hong Kong. They comprised 15 cases of M2, two cases of M4 and one case of M1 according to FAB criteria. Auer rods (17 cases) and dysgranulopoietic features (15 cases) were very frequently observed. Two cases showed marrow eosinophilia while blast cells in one patient demonstrated erythrophagocytic activity. Chromosome changes in addition to t(8;21) were seen in 14 patients, the most common of which was loss of a sex chromosome (10 cases). Of the 14 patients treated with intensive chemotherapy, 13 (93 per cent) entered complete remission with a median event free survival (EFS) and overall survival (OS) of 11 and 24 months respectively. The probability of EFS and OS at 3 years were 33 +/- 14.3 per cent and 55.1 +/- 15.6 per cent respectively with a median duration of follow-up of 22 months. When compared with AML having no t(8;21) treated similarly in the same period, we could not demonstrate a better clinical outcome for t(8;21) AML. PMID- 9375035 TI - Telemedicine in Australia. 2: The Health Communication Network. AB - The Health Communication Network (HCN) in Australia is reviewed. Early interest from both the government and the medical community led to the establishment of a number of pilot services. Because of the community interest in privacy issues, determined efforts to understand and build structures to cope with privacy have been made. The first HCN services began to be tested in 1995, and progressive expansion is planned. The HCN, while supported by the government, is a separate, commercial entity, and much early work has thus focused on corporate governance, so that it will be able to do what it was designed for. PMID- 9375036 TI - Telecardiology: supporting the decision-making process in general practice. AB - To assess the initial phase of a telecardiology diagnostic service for general practitioners (GPs), we provided 93 GPs in 26 health centres with direct telephone access to a cardiologist, and equipped them with hand-held, automatic standard 12-lead electrocardiogram (ECG) transmitters for on-line cardiac consultations and ECG interpretation in their daily practice. Clinical details, reason for consultation and the ECG signal were transmitted from the GPs' practices or the patients' homes. A consultation followed and a full report, including ECG print-out, was then sent to the GP. During an 18-month study period, 2563 consultations were carried out. The system allowed the identification of 479 patients (19%) with urgent cardiac problems and the remaining 2084 (81%) in whom admission or outpatient investigation was unnecessary. Following the study, we distributed a questionnaire asking the GPs to rate the quality, define the use and consider the benefit of the service to their daily practice. We conclude that a telecardiology diagnosis and ECG interpretation service is simple, reliable and efficacious in routine primary care. It offers instant access to cardiac assessment and supports the decision making process of GPs. A preliminary cost comparison with a conventional referral indicated that a teleconsultation was substantially cheaper. We expect that the future incorporation of teleechocardiography would expand the scope of telecardiology even further and allow comprehensive cardiology consultations. PMID- 9375037 TI - Satellite-delivered medical education and training for central Europe: a TEMPUS project. Trans-European Mobility Programme for University Students. AB - This paper reports the experience gained in delivering continuing and postgraduate medical education by satellite to update medical teachers in Central Europe. An infrastructure of receiving sites was established in the Czech Republic, Slovakia, Poland and Hungary. The sites participated in regular, live interactive broadcasts on a range of medical education topics. Over three years a network of sites was established incrementally and a national coordinator identified for each country, who fed back from national coordinating committees to an overall steering body. In the final year a formal evaluation revealed high satisfaction levels and maintenance of activity during the grant period. The major problems related to a lack of telephone lines to facilitate interactivity, the timing of the programmes, and the need for training in medical English language. Video libraries were established, and the majority continued to be active at the end of the project grant. Material was incorporated into both undergraduate and postgraduate education. It is calculated that continuing professional development can be delivered at less than 18 ECU per participant per country. PMID- 9375038 TI - The Telemedicine Information Exchange (TIE). AB - An on-line information service, the Telemedicine Information Exchange (TIE), was established to provide a comprehensive source of telemedicine information. The TIE comprised a number of frequently updated, searchable, linked databases, each dealing with an important aspect of telemedicine. These included an extensive bibliography on telemedicine consisting of more than 2000 citations, many with abstracts. There was also a series of topical sections describing current telemedicine projects, products and services, legislation, funding, research activities, and news in the field. The TIE was designed to exploit the features of electronic information storage: hypertext linking between related pieces of information; specialized views (technical, legal, and business) of the bibliographic database; and usage monitoring to determine which data were most frequently accessed and therefore where any enhancement should be done. The TIE was made available via the World Wide Web, by remote telnet access over the Internet, and via modern. The rapid increase in the usage of the TIE since its introduction in April 1995 indicated that the TIE satisfied a need in the telemedicine community. PMID- 9375039 TI - Telepathology using Internet multimedia electronic mail: remote consultation on gastrointestinal pathology. AB - The feasibility of using the Internet for remote pathology consultation was examined. We assessed the diagnostic agreement between two groups of pathologists who independently evaluated histopathological cases exchanged by Internet electronic mail. The exchange was between two different workstations using readily available software not specifically developed for telemedicine. Data and images from 76 cases were transmitted to four pathologists. An average of 4.5 images per case were transmitted at compression ratios of between 6:1 and 40:1, corresponding to 250 kByte of data per case. In two cases the remote pathologists could not make a diagnosis. Agreement was reached in 63 of the other 74 (kappa = 0.79). In 11 cases (15%) there was a misdiagnosis. However, the results are encouraging and suggest that Internet electronic mail can be used successfully for remote consultation in pathology. PMID- 9375040 TI - Subspecialty radiology consultation by interactive telemedicine. AB - This investigation tested the hypothesis that interactive, low-resolution telemedicine is an effective method for radiologists' consultations. The case material consisted of radiographs and digital images from patients with 14 paediatric diseases readily diagnosed by imaging, and 10 matched controls. The original images were first evaluated by a general radiologist, who entered a diagnosis. He or she then discussed the case with a paediatric radiologist who had access to the same images via low-resolution interactive video. Following the consultation the general radiologist could change diagnosis. The experimental subjects were three teams of general and paediatric radiologists. Observer performance and case-comparison methods were used for analysis. The results showed that the general radiologists' diagnostic accuracy improved after telemedicine consultation with the subspecialist, the area under the ROC curve improving from 0.648 to 0.709. The interactive consultation was judged valuable by all participants. We conclude that low-resolution interactive telemedicine is of value for consultation between generalists and subspecialists in radiology. PMID- 9375041 TI - Digital transmission of 12-lead electrocardiograms and duplex speech in the telephone bandwidth. AB - A system was developed which allowed the simultaneous communication of digitized, full duplex speech and electrocardiography (ECG) signals in realtime. A single band-limited channel was used over a standard telephone line providing 3 kHz bandwidth. The full duplex speech was compressed to 2400 bit/s using linear predictive coding, while multiple ECG signals were processed by a novel ECG compression technique. Extensive use of digital signal processing reduced the combined bit rate to less than 9600 bit/s, allowing the use of low-cost commercial modems. The ECG communications system was tested in clinical trials. It enabled a hospital-based clinician to provide diagnostic and treatment advice to a remote location over the standard telephone network. PMID- 9375042 TI - What do physicians think of telemedicine? A survey in different European regions. AB - To discover the perception of telemedicine in a sample of physicians not yet participating in telemedicine networks, a questionnaire was sent to doctors in different European countries. The questions covered various general aspects of telemedicine. The percentage of questionnaires returned ranged from 12% (Central Europe) to 27% (Spain). Apart from the rather disappointing response rates the results document a strong interest in telemedicine on the part of the physicians surveyed. Knowledge of the existence of telemedicine was high. Most of the respondents would have liked to have had their clinic's telemedicine system in their own laboratory. More than 50% of the physicians thought that their work would be improved by using telemedicine. Respondents from Central Europe were significantly less enthusiastic about telemedicine than those from other regions. However, the answers to the majority of the questions were similar in the different groups. PMID- 9375043 TI - Telepsychiatry in an inner-city community psychiatric service. PMID- 9375044 TI - Evaluation of teleradiology in Scotland. PMID- 9375045 TI - Organization and activities of the International Radio Medical Centre (CIRM). AB - The International Radio Medical Centre (CIRM) was founded in 1935, to provide free medical assistance by radio to ships with no doctor on board and others who cannot be reached by a doctor. In 1950 CIRM was established as a non-profit making foundation and has benefited since 1957 from an annual contribution from the Italian government. The results achieved by the Centre over 61 years include medical assistance to 42,935 patients on board ships (as well as on small islands and aircraft), with 375,264 medical messages received and transmitted. CIRM is organized into a medical service, a telecommunications service and a studies section. The 24-h continuous medical service is provided by doctors at the CIRM headquarters. The doctor on duty gives instructions for managing the case. If necessary the medical service will coordinate the patient's hospitalization at the nearest port with suitable medical facilities or arrange the patient's transfer to another ship with a doctor on board, or an airlift. The telecommunications service receives requests for assistance, locates the ship or whoever made the request, passes the call to the doctor on duty, and relays the doctor's response to those requesting assistance. The studies section, established in 1957-58, researches occupational pathologies of sailors and contributes to their prevention. This provides a scientific basis for improving medical assistance to sailors at sea. PMID- 9375046 TI - Telecar: an Italian telecardiology project. AB - The Telecar (tele-assistance cardiology) project was an example of tele assistance between health centres of the Regione Lazio in Italy. The project was approved by the Ministry of Health, financed with 500,000,000 lire and carried out by an operative station within 'La Sapienza' University (Rome). About 40 of the health centres in Lazio that did not have cardiologists or electrocardiography (ECG) equipment were provided with telematic instruments (Cardiophone and fax). With this equipment, they were able to transmit ECG signals and receive copies of ECG reports. The 40 health centres included first aid clinics, 'guardia medica' surgeries and community centres. The project was carried out between 1989 and 1992. During these three years the health centres transmitted a total of 4807 ECGs, 2057 (43%) of which were routine, the remaining 2750 (57%) being suspected emergencies. Of the suspected emergencies, 681 cases (25%) had a confirmed abnormality. We can confirm that telematic aids are very important for an operative station, where all kinds of emergencies must be dealt with. PMID- 9375047 TI - An economic analysis of teleradiology versus a visiting radiologist service. AB - An economic analysis of the teleradiology service provided by a university hospital to a local hospital without radiologists was carried out. The average workload at the local hospital was 6000 patients (8000 examinations) per year. In these circumstances teleradiology cost NKr108 per patient, in comparison with NKr178 per patient for the visiting radiologist service which had previously been provided. The total cost of the teleradiology service amounted to NKr646,900 per year; in comparison the visiting radiologist service cost NKr1,069,000 per year. Calculations showed that for teleradiology to be cheaper, the workload had to exceed 1576 patients per year. A sensitivity analysis showed that assuming a shorter equipment lifetime, for instance four years rather than six years, made the threshold value 2320 patients per year instead of 1576. PMID- 9375048 TI - A multiparameter, PC-based telemetry unit for biomedical signals. AB - A low-cost, general-purpose telemetry system was developed for use in rural health centres, hospitals, ambulances and clinics. It was designed to transmit a range of analogue biomedical signals using various communications media. The system was tested using different telephone systems, including mobile telephony. The results showed a maximum sample rate of 1.6 kHz using the public telephone network. With three data channels the system produced sample rates of 500 Hz at 8 bit/sample. Typical overall delay times were below 100 ms. Mobile tests showed that the GSM telephone was superior to the Nordic mobile telephone (NMT 900). In field tests, sample rates of 990 Hz were obtained using GSM telephony. Bit error rates were less than 10(-7) for all applications and high-fidelity regeneration was obtained at the receiver. The tests showed that the system was well suited for telemetry of analogue biomedical signals in a broad range of telemedicine applications. PMID- 9375049 TI - Accuracy of routine echocardiographic measurements made by an inexperienced examiner through tele-instruction. AB - The reproducibility and accuracy of routine echocardiographic measurements made by an inexperienced doctor using tele-instruction were evaluated. Thirty-eight patients were first examined at a local hospital by an inexperienced doctor instructed by a specialist 450 km away at a university hospital. The specialist then examined the patients at the local hospital using the same equipment, after an average of 50 days. The accuracy of M-mode and quantitative Doppler measurements was comparable to that observed in reproducibility studies made under normal examination conditions. There were no systematic measurement errors. No important M-mode information was missed except evidence of left ventricular hypertrophy in six patients. In the two-dimensional examination there were differences of clinical significance in only three patients. There were no clinically important differences in the Doppler quantification of mitral and aortic regurgitation. Tele-instructed echocardiography is also an excellent educational tool, allowing an inexperienced examiner gradually to take responsibility for the local echocardiographic service. PMID- 9375050 TI - Teleradiology services for a rural hospital: a case study. AB - We investigated the perceived quality of teleradiology services offered at a rural hospital in comparison with radiology provided by three other methods: 'circuit riding', an on-site radiologist, and a hybrid arrangement. The research design was a case study, with interviews of administrators, technologists and physicians at the rural hospital, followed by a structured survey of all staff physicians. Responses were analysed both qualitatively and quantitatively. Both interviews and the survey indicated that teleradiology was perceived to be as accurate as on-site film interpretation. All other aspects of the service- efficiency, reports, communications and the overall contribution to patient care- were judged to be poorer than on-site radiology. We conclude that the provision of acceptable teleradiology requires considerable attention to all aspects of the radiology service, with attention to differences in institutional culture and mission, and to communication. PMID- 9375051 TI - Radiological videoconferencing in Sweden. AB - For the last four years there has been a videoconferencing link between the Karlskrona hospital and the university hospital of Lund. Because of a need to transmit angiographic films, its use has been gradually expanded to become an everyday routine, used for both elective and emergency examinations. During 1994 and 1995, 1121 cases were examined over the video link. Apart from 156 normal cases all were discussed with surgeons, most at 96 weekly conferences but approximately 50 at conferences taking place as soon as possible after the examination. Assuming that an average of three doctors attended the conferences before the video link was available, this amounts to a saving of 3 x 8 h in travelling time per videoconference. The average salary was 300 SKr/h and train tickets cost a further 400 SKr per person. The cost of the ISDN connection was approximately 1800 SKr/conference. The net gain was thus about 6500 SKr per videoconference, without taking into account the work that could be done with the doctors still in Karlskrona after the conference. PMID- 9375052 TI - Diagnosis of neonatal congenital heart defects by remote consultation using a low cost telemedicine link. AB - To determine whether telemedicine could assist in the earlier diagnosis of neonates with congenital heart disease (CHD) in an area hospital remote from a paediatric cardiologist, we established a low-cost telemedicine link between the neonatal unit of a district general hospital and the regional paediatric cardiology unit. Realtime ultrasound images of babies suspected of having CHD were obtained by a paediatrician and transmitted for realtime interpretation by a paediatric cardiologist. In a four-month pilot study, 10 neonates were studied in this way. In eight of the ten cases, the diagnosis made over the telemedicine link was confirmed subsequently in a direct examination at the regional unit. In one case the patient died before the direct examination was possible. In one case two small muscular ventricular septal defects were missed on the remote examination. Our early experience suggests that, with realtime guidance by a paediatric cardiologist, transmitted images of sufficient quality to allow confirmation or exclusion of major cardiac defects can be obtained. This form of remote consultation should improve morbidity and mortality rates by reducing the waiting time for specialist diagnosis and treatment. PMID- 9375053 TI - Experimental telemedicine in orthopaedics. AB - There have so far been few telemedical applications in orthopaedics. This experiment involved clinicians in three different locations, two in Helsinki and the third in Tampere, consulting one another simultaneously. We used an ATM network to transfer X-ray pictures, digitized by a 12-bit CCD scanner and archived in a central image server. The consultations between the clinicians and the examination of the patient were transmitted by a videoconferencing system using the ISDN. We found that telemedicine offers new possibilities in orthopaedics, for clinical work, for training and for research. PMID- 9375054 TI - Melanoma--diagnosis by telemedicine. PMID- 9375055 TI - Telepresence for decision support offshore. PMID- 9375056 TI - The management of clinical risk in telemedicine applications. AB - Any telemedicine application should be viewed in terms of its health-care context, the clinical process it is enabling, and whether it is appropriate to apply telemedicine to that process. Telemedicine should be used as a tool to enable the transfer of clinical information which, by being transferred, will reduce clinical risks. Because managing clinical services involves knowing where clinical decisions are being made, it is important to ensure that telemedicine activity is recorded as part of the routine clinical and investigative data sets that will be kept for clinical audit and health-service costing purposes. There may be areas of health-care delivery where the telemedicine solution becomes the treatment of choice. In this event, not to provide telemedicine may be unethical and may expose a service to high clinical risk. If a service is based on the use of telemedicine, it is important to ensure that the technical specifications are adequate, that the system is sufficiently reliable, and that there are adequate back-up provisions in the case of system failure. PMID- 9375057 TI - Low-power radio telemetry: the potential for remote patient monitoring. AB - Radio-based signalling devices will play an important role in future generations of remote patient monitoring equipment, both at home and in hospital. Ultimately, it will be possible to sample vital signs from patients, whatever their location and without them necessarily being aware that a measurement is being taken. This paper reviews current methods for the transmission by radio of physiological parameters over ranges of 0.3, 3 and 30 m, and describes the radiofrequency hardware required and the carrier frequencies commonly used. Future developments, including full duplex systems and the use of more advanced modulation schemes, are described. The paper concludes with a case study of a human temperature telemeter built to indicate ovulation. Clinical results clearly show the advantage to be had in adopting radio biotelemetry in this instance. PMID- 9375058 TI - Videoconferencing in psychiatry: a survey of use in northern Norway. AB - A survey of the use of videoconferencing in mental health care was carried out in northern Norway. A questionnaire was distributed to all user institutions in northern Norway at the same time that ISDN became available, in mid-1995. The questionnaire completion rate for locations recorded as participants in videoconferencing sessions was 62%. Within six months, a total of 1028 persons had participated in 140 videoconferencing sessions from 35 institutions. The purposes of videoconferencing included meetings (50%), supervision, training and teaching (31%), clinical consultations (14%) and tests or demonstrations (5%). The alternative forms of contact which videoconferencing replaced included travel (59%), no contact (25%), telephone (14%), and mail or fax (2%). No problems were reported in 55% of the sessions; in 19% there were audio problems, in 14% there were picture problems, in 5% attempts to connect failed and in 5% disconnection occurred. The majority of users (87%) reported that they were satisfied or very satisfied with the facility; 8% were uncertain and 5% were less satisfied or totally dissatisfied. Continued surveying will provide longitudinal data on the diffusion of telepsychiatry in northern Norway. PMID- 9375059 TI - Factors affecting the electronic communication of radiological information to an intensive-care unit. AB - In order to examine communication of radiological information under circumstances where rapid exchange of information was essential, we studied communication of non-routine portable chest radiographs to an intensive-care unit (ICU). Images and reports were available through the usual communication channels and through a PACS workstation in the ICU. Data were obtained to determine how quickly and by what means ICU physicians first viewed images and received radiologists' reports of chest radiographs. Peak information demand occurred within 4 h of the examination. The most rapid means of communication was for the physician to visit the radiology department. Image viewing and report receipt were tightly coupled, usually for images which were first viewed as hard copy. PACS performance suffered from unreliable film digitization and delayed report transcription. Integration of computed radiography and digital dictation into a PACS could markedly reduce the delays in ICU physicians' access to radiological information. PMID- 9375060 TI - Telemedicine applications in an integrated mental health service based at a teaching hospital. AB - Psychiatric applications have predominated in Australian telemedicine in recent years. This paper describes the development of the first telemedicine system for an integrated mental health service based at a teaching hospital. Much effort was devoted to training and education for staff. Within about six weeks of the system being installed, over 80% of all clinical administrative staff, from all the mental health disciplines of the integrated service, had completed a formal training programme. Applications within the service included direct clinical work and the use of videoconferencing in preference to standard telephony over short distances. Applications external to the service, over distances of thousands of kilometres, included clinical supervision and teaching. Evaluation is continuing. PMID- 9375061 TI - Teleradiology at a children's hospital: a pilot study. AB - A pilot teleradiology project was conducted between the Royal Alexandra Hospital for Children in Camperdown, central Sydney, and Nepean Hospital in Penrith, about 48 km away. Over three months 575 paediatric radiographs were transmitted at full resolution. The results demonstrated that it was possible to transmit paediatric chest images of diagnostic quality in a reliable and secure manner. Mean transmission time per image was 3.26 min using ISDN, which was considered to be acceptable. Costs were calculated in terms of transmission, equipment, maintenance and staff components. The cost per image transmitted would vary from A$80 for 2500 images per year to A$34 for 10,000 images per year. The experience of the pilot study suggested that more widespread introduction of high-quality paediatric telemedicine in Australia would be feasible. Adoption of the technique would have major implications for paediatric health care, including potential improvements in patient management due to quicker diagnosis and earlier intervention, and potential savings through avoiding transfer of some emergency cases. PMID- 9375063 TI - Telepsychiatry in rural South Australia. PMID- 9375062 TI - Teledentistry: protocols for the transmission of digitized radiographs of the temporomandibular joint. AB - Tomograms of the temporomandibular joint were digitized in three different formats using a PC-based system. The image resolution for various projections was determined at different camera-film distances. Three series of images were transmitted by telephone, and transmission times were measured. The original radiographs, the digitized images, the transmitted images and the transmitted-and printed images were presented to 10 observers, who were asked to rate image quality. No difference in image quality was found between the initial digitized and the transmitted images. However, transmitted and transmitted-and-printed images were of significantly lower quality than the original radiographs or the digitized images viewed on a computer monitor. Transmission time was reduced significantly (50%) by cropping the images before transmission. The image quality of individual radiographs was better than radiographs formatted as a series. PMID- 9375064 TI - The Tele-Healthcare Information System at the Chinese University of Hong Kong. PMID- 9375065 TI - Telemedicine and developing countries. AB - A committee was established by the International Telecommunication Union in 1994 to study telemedicine, with particular reference to developing countries. A questionnaire was used to gather data. Fifty-eight responses were received, two thirds from developing countries. In most developing countries the user did not pay for the telemedicine service, at least not directly. There were few instances of a commercial telemedicine service, and in most countries the telemedicine service was subsidized by the government or another party. The telemedicine 'value chain' describes how equipment suppliers, telecommunications operators and health-care professionals deliver their products or services to the client, who is eventually the ultimate user. Quite different configurations are conceivable, and an analysis of what could be a sustainable, cost-effective value chain in developing countries is required. It is clear that the rapidly growing interest in telemedicine challenges the leaders of the medical establishment to rethink the ways they provide their services and to address the medical needs of areas where such services are absent or in short supply. PMID- 9375066 TI - Three generations of telecare of the elderly. AB - The increasing number of elderly and infirm people living alone in their own homes is creating the need for new personal emergency response systems based on public telephone and cable networks. While existing systems enable clients to summon help in the event of illness, future services are likely to make use of evolving technologies to provide automatic sensing of emergencies and to predict long-term deterioration in health, using activity profiles. The characteristics and requirements of these second-generation systems are discussed and predictions are made about the innovative services and facilities that may be available in third-generation systems, when broadband communication is available to the home. PMID- 9375067 TI - User adoption issues in renal telemedicine. AB - We carried out a longitudinal survey to evaluate the users' attitudes to the introduction of telemedicine into the dialysis units of a renal ward in South Australia. The first questionnaire was distributed to all members of staff involved with the introduction of the system. There were 44 responses (80%). Staff were fairly positive about the telemedicine system, and felt that it was easy to use and reliable. They also clearly felt that the confidentiality and privacy offered by the system in an open ward were unsatisfactory. A second questionnaire was distributed to all staff about six months later and there were 40 responses (66%). Of these, 22 could be matched with the responses from the first survey (a response rate of 50% from the first sample). There were no significant differences in the staff members' feelings between the two surveys, except in two cases: there were significant changes in staff opinion about the degree of confidentiality (P < 0.05) and privacy (P < 0.01) offered by the system, with attitudes becoming more positive in each case. The results indicate the need for dialogue with users, in order to address their concerns regarding the system and practical difficulties. This study highlights the importance of planning, effort, cooperation and an appropriate culture within a renal unit in order for telemedicine to be accepted. PMID- 9375068 TI - US policy support for telehealth: organizational response to a new policy environment. AB - A sample of 40 from 176 public policy organizations in Washington, DC, was studied. The organizations were those whose leadership was deemed necessary to develop a new strategic vision of electronic technologies to support public health. The results showed that large, secure and well positioned organizations became active only to the extent of their mandates, while smaller and less influential groups, which were freer to think and act innovatively, had an incentive to work with other organizations to gain effective support for their policy positions. The conclusion is that the constituencies of leading policy organizations will have to ensure that well connected leaders and environmental scanning structures guide their organizations and that they have the institutional capacity to develop unconventional strategies to meet health challenges. PMID- 9375069 TI - An evaluation of telemedical support for a minor treatment centre. AB - A low-cost telemedicine link was established from an accident and emergency department in Belfast to support nurse practitioners running a minor treatment centre (MTC) in London. During the 12 months before the introduction of the telemedicine link, 6729 patients were seen in the MTC. Of these, 155 (2.3%) were referred to the nearest accident and emergency department and 802 (11.9%) were referred to their general practitioner (GP). During the first 12 months of the use of the telemedicine link, 9972 patients were seen in the MTC. Of these, 147 (1.5%) were referred to the accident and emergency department and 383 (3.8%) were referred to their GP. During the evaluation period, 51 patients were seen using the telemedicine link, representing 0.5% of all MTC attenders during that period. The total number of teleconsultations was less than expected. The reasons for this difference include random variation, but could also include confidence resulting from the presence of the link and a training effect. The telemedicine link for trauma and minor injuries was an extremely cost-effective way of providing medical expertise to cover the clinical risk of the 0.5-1.5% of the case load that required expert medical opinion. The direct costs of on-site medical staff would have been 50,000 pounds per annum, excluding overhead charges. The annual cost of the videolink, including overheads, was 7250 pounds, amounting to a saving of some 42,000 pounds per annum. PMID- 9375071 TI - Remote continuous physiological monitoring in the home. AB - As part of a larger study we established a remote physiological monitoring network to investigate cardiorespiratory function during sleep in 400 infants in their homes. The objective of the study was to link measurements made at three weeks and three months of age with detailed measurements of maternal and fetal nutrition during pregnancy and subsequent outcome (growth, development and cardiorespiratory diseases). Five infants per night were monitored anywhere within a radius of 10 miles (16 km) of the remote hub. Of 800 overnight studies on 64 (of 400) infants, 99 were completed. Options allowed downloading data from monitor memory as well as review (on- and off-line) from the infants' or nurses' homes, the hub and the Oxford telemonitoring centre. The reasons for these measurements being made at home were to ensure physiological accuracy and to reduce cost. The network was effectively run by local community nurses; with the exception of the size and cost of the monitors, it had all the elements of a remote primary-care clinical service. PMID- 9375072 TI - Establishing a postgraduate qualification in remote health care. AB - The British Antarctic Survey (BAS) provides medical care for the scientists and support staff working on British scientific bases and research vessels in the Antarctic. The BAS directs significant resources towards medical research, so a doctor who does not complete the research component of the programme of training and medical duties represents a partially wasted investment. Additionally, the professional experience gained by the doctor is appropriate for a postgraduate qualification. For these reasons, the training, clinical placement and research undertaken by doctors were formalized as a masters degree in 1992. The objectives of the MSc degree were to optimize the benefits of the training and research for Antarctic doctors and their patients, and to improve the quality of the research output. In the three years before the degree was introduced, only 25% of doctors produced a useful research output. Following the introduction of the MSc, this figure rose to 88%. PMID- 9375070 TI - The design and preliminary evaluation of a home electrocardiography and blood pressure monitoring network. AB - A home electrocardiography (ECG) and blood pressure (BP) monitoring network was established in Beijing. The network consisted of three parts: (1) the home ECG and BP monitoring devices; (2) the monitoring centre at the hospital; and (3) the data communication network, for which we chose the public telephone network. The system was tested in our university hospital for two months with 30 patients and six normal volunteers. A preliminary evaluation by the users indicated that the system was acceptable in terms of its efficiency and effectiveness. This paper describes the system design, the preliminary testing procedure, and results. PMID- 9375073 TI - From acute leukaemia to multiple myeloma: clarification of a diagnosis using tele oncology. PMID- 9375074 TI - Videoconferencing and coronary angiography. PMID- 9375075 TI - Teleconsulting: a practical account of pitfalls, problems and promise. Experience from the TEAM project group. AB - In Wales the Tele Education and Medicine (TEAM) project has given clinicians, in both the primary- and secondary-care sectors, practical experience in teleconsulting. From this project we have been able to identify the potential pitfalls and problems in developing and using this new technology. These problems include: using teleconsulting simply because it is fashionable; the failure to base it on the needs of the patients and the primary-care physicians; the failure to validate accuracy, acceptability and cost; the failure to adapt to new technical improvements; and the failure to scale up from a pilot project to a wider teleconsulting service. In our experience technical support is essential and is best facilitated by multisite cooperation, rather than small free-standing projects. PMID- 9375076 TI - A communication system supporting simultaneous planning and execution in cranio maxillo-facial surgery. AB - This paper describes the development of a system for simultaneous planning and execution of surgical operations in the cranio-maxillo-facial area. Simultaneous planning and execution is the process of taking an implicit task description, planning a sequence of explicit execution commands (e.g. for robots) and monitoring their execution. As the execution planning process is run completely on-line, during the execution of the assembly task, the planning process is highly reactive, based on sensor information about the robot's present environment. In order to meet the problem that medical data are usually complex and need time-consuming preprocessing, an appropriate architecture for evaluating sensor data has been developed. In this paper, a detailed presentation of the phases of execution planning and sensor data evaluation is given. As an example, the execution of a LeFort I osteotomy is presented. PMID- 9375077 TI - Teledermatology in the Highlands of Scotland. AB - A pilot study of telemedicine consultations of 51 dermatology patients showed that the technology worked well, with the diagnosis being able to be made in most patients and over half of the patients being able to be dealt with through this medium only. It could therefore have a valuable screening role. However, many of the patients, in spite of the obvious advantage of an immediate consultant opinion, felt it would be more appropriately used as a review technique. PMID- 9375078 TI - Telemedicine project RATEMA--radiation accident telecommunication medical assistance system. PMID- 9375079 TI - RETAIN--an ATM pilot project for applications in health care. AB - The availability of ATM-based broadband wide-area networks facilitates a range of new applications in health care, especially the performance of videoconferences combined with software for computer-supported cooperative discussion and diagnosis of digital medical images. This report about a research project for applications of the 'European ATM pilot network' in radiology describes the technical, economic and structural framework for the application of broadband technology in health care. PMID- 9375080 TI - Field test to evaluate telepathology in telemedicine. AB - Telepathology is currently performed only on prototype systems. The application of telepathology consultations differs from the conventional procedure because of the technical and cost restrictions. This paper outlines technical concepts and the principal hardware and software modules necessary for telemicroscopy equipment. A field test to gather information concerning the user needs and to evaluate parameters of telepathology consultation sessions is reported. PMID- 9375081 TI - Telepathological (image transmission) configuration. AB - The Laboratory for Biomedical Informatics (LBMI) has developed a digital microscope control module incorporated into an image analysis system. This is now equipped with an ISDN switch box for linking up with a remote computer-based station for delivering histopathological services. The FRAME, client/server integrated software, was developed to initiate the communication link, adjust the microscope settings, acquire and transmit images. This LBMI telepathology initiative employs simple solutions to arrive at the point of prototyping and demonstrating the state of the art on the one hand and encountering the prevailing problems in order to deliberate on possible remedies on the other. PMID- 9375082 TI - Telepathology through the Internet. PMID- 9375083 TI - Evaluation of an international telepathology system between Boston (USA) and Dijon: glass slides versus telediagnostic television monitor. AB - A telepathology network developed by Resintel (Dijon) has proved valuable in interactive situations, where two physicians converse by telephone, showing each other the part of the lesion they wish to discuss. In future this interactive process could be replaced by an electronic mailing service in which a limited number of images are taken from the slide, but this technique needs to be assessed in comparison with traditional microscopic diagnosis, when the pathologist can screen the entire slide. The present study compared diagnoses achieved through the traditional methods of current pathology practice with diagnoses achieved through a selection of images on a telediagnostic TV monitor. The kappa coefficient between the two protocols was 0.26 (SE = 0.06), which allows us to conclude that there is a fair reliability between video and glass slide diagnoses. PMID- 9375084 TI - Telematic electrodiagnosis. AB - Using the Electrodiagnostic Neurophysiological Automated Analysis (ENAA) telematic system, 1560 standardized electrodiagnostic tests have been performed on 70 normal subjects and 320 patients in five laboratories in three European countries. The data from each patient have been transmitted from the five satellite laboratories to the Bristol Telematic Electrodiagnostic Centre (BRITEC), housed in the Bristol Eye Hospital, where they were evaluated and the conclusions transmitted to the place of origin. The results from the normal subjects were not significantly different between laboratories. Also patients with specific types of disease had similar results in all laboratories. The results from both the normal subjects and the patients show that a working prototype for providing telematic electrodiagnosis is available and has been well received by both clinicians and patients. PMID- 9375085 TI - Telemedicine and safety. PMID- 9375086 TI - Telemedicine in British Airways. AB - In the year ending March 1994, British Airways (BA) carried in excess of 30 million passengers worldwide. There was a total of 2078 reported in-flight medical incidents, with 18 unscheduled diversions for medical reasons. The commonest reported conditions were faints, diarrhoea and vomiting. The BA aircraft medical kit content exceeds the statutory minimum requirement and all cabin crew undergo training in first aid and life support. There is a BA doctor on 24 h call with whom an aircraft captain may communicate via a high-frequency radio link. This link has limitations and immediate contact is not always possible. BA is installing satellite communication facilities in new aircraft and the application of telemedicine utilizing this facility is being explored. PMID- 9375087 TI - Mobile telecare--a mobile support system to aid the provision of community-based care. PMID- 9375088 TI - Realtime three-dimensional remote medical skills acquisition. AB - Three-dimensional techniques are gaining widespread use in a number of disciplines, including medicine, where the visualization of depth information is not only useful but important. Both computer-generated 3-D imaging and 3-D video are set to become increasingly important tools for both diagnosis and teaching. In this paper we will present some of the work that we are currently undertaking using 3-D techniques for remote surgical skills acquisition. This work is based on the use of a small headset with twin miniature video cameras, video codecs, two different 3-D visualization systems and BT's ISDN telecommunications network. PMID- 9375089 TI - Solo surgery--with the aid of a robotic assistant. AB - In the interests of cost containment this study was performed to compare the cost effectiveness of utilizing a robotic assistant instead of a human assistant. Twelve patients undergoing laparoscopic bladder neck suspension were studied retrospectively. In six of these cases a human assistant was utilized and in another six a robot arm was utilized to hold and manoeuvre the laparoscope and camera. Evaluations have previously been made showing the improved steadiness and clarity of picture when utilizing the robot rather than a human and in this case the length of surgery was compared and the cost of the equipment and all personnel evaluated. The differences in length of surgery between both groups was not statistically significant. The cost of the robotic arm was less than that of human systems. This depends on the volume of surgery and may vary between institutions. In conclusion, a robotic assistant is seen to be a cost-effective device taking the place of the traditional assistant. PMID- 9375090 TI - Early experience with telerobotic surgery in children. PMID- 9375091 TI - Integrated telematic support for paediatrics: a practical model. AB - This paper describes the benefits gained and the organizational and practical considerations involved in establishing a relatively low-cost telematic support network for paediatric care and research. It is based on a case study in north east England, where such a system has been implemented, supporting multimedia conferencing and reference facilities, postgraduate education and management information. The role of this type of service in regional health-care provision is discussed, for paediatrics and other disciplines. PMID- 9375092 TI - Telemedicine and the nurse: the benefit or burden of new technology? PMID- 9375093 TI - Teleradiology or teleconsultation for emergency nurse practitioners? AB - Twenty radiographs showing subtle orthopaedic findings were transmitted to three emergency physicians. Fifty-seven of the 60 attempted diagnoses were correct. We found the primary radiographic film had to be well centred, exposed, true and penetrated for successful transmission. There is a considerable element of familiarization with the technology. The software should permit simultaneous annotation from the two sites and additional cameras are necessary to enable emergency nurse practitioners (ENPs) to show the injured part. The 20 radiographs took 120 min to interpret with teleradiology rather than 10 min of viewing conventional films. The extra time for teleradiology is due to readers asking for multiple areas of the radiographic image to be enlarged before making a decision. We feel that ENPs should not engage in teleradiology but rather telemedical consultation. PMID- 9375094 TI - Telepsychiatry: outpatient psychiatry by videolink. PMID- 9375095 TI - Psychiatry: communications technology and education in mental health. PMID- 9375096 TI - Remote trauma management--setting up a system. AB - A telemedicine link to enable nurse practitioners at a remote minor injuries unit to obtain advice from an emergency physician at a main accident and emergency department is feasible and worthwhile. However, it is fraught with difficulties. These include technical difficulties, training problems, familiarization with the technology and provision of enough emergency physician time for the much longer duration of a full consultation. When choosing the equipment, attention has to be paid to the cameras, lighting, echo cancellation, layout of rooms, privacy and ambience. It is useful to obtain the system from suppliers who know what they are doing and have adequate backup of appropriate technical expertise, because each installation is different and difficult. Our experience suggests that anyone wishing to use similar technology should be prepared to be doggedly determined to learn the system, iron out kinks and motivate all concerned. The project will need to be driven. The technology is still at a stage where frustration and delay are significant. However, it is rewarding and very useful if the staff overcome its shortcomings and in due course all are pleased that they participated. PMID- 9375097 TI - Confidentiality and ethics in telemedicine. AB - This paper reviews the results of a survey of 200 members of the public. The topics examined were ethical issues and patient confidentiality related to the use of telemedicine between an accident and emergency department and emergency nurse practitioners providing a minor accident treatment service (MATS) based in community hospitals. A discussion group of eight respondents was established and a resume of their views is included. PMID- 9375098 TI - ECG handling on a telemedicine platform. AB - In this paper we present the principles of a new platform developed for handling ECG signals in a telemedicine setting. We focus on three basic services: an ECG file management system (acquisition, storage, transmission); ECG-oriented teleconferencing; and realtime transmission of ECGs over the telephone network. This work has been carried out in the context of national and EU-sponsored projects. Its main purpose was to help patients from remote or isolated areas, like small islands, with insufficient health-care services, to get appropriate and experienced medical care directly from large central hospitals. We present the design and the basic operations of the ECG handling system. PMID- 9375099 TI - Telecardiology services in the Aegean islands. AB - Telecardiology services established between the Onassion Cardiac Surgery Centre in Athens and the Primary Health Care Centre (HCC) of Naxos in the Aegean provide 24 h support. During the testing period more than 50 cases were analysed, diagnosed and treated in Naxos HCC, under the supervision of the on-call cardiologists of the Onassion Cardiac Surgery Centre. One patient with an acute myocardial infarction was evacuated to a tertiary hospital in Athens. The services are modelled in a way that they could be applied to five more HCCs in the Aegean. Emphasis is being put on the customization of the electronic medical records for facilitating the work of the primary-care physicians to cope with cardiology emergencies and long-term follow-up of cardiac patients. PMID- 9375100 TI - The teleambulance. AB - The teleambulance aims to facilitate adequate medical treatment by initiating and guaranteeing maximum preparation and immediate hospital handling of the patient either at the scene of an incident or during transportation. Following the problem definition and the identification of the medical fields the technology can address, field research was conducted to investigate the state of the art from the point of view of the prospective end user. This paper presents the development of the teleambulance workstation. PMID- 9375101 TI - Implementing global telemedicine: experience with 1097 cases from the Middle East to the USA. PMID- 9375102 TI - Point-to-point telemedicine using the ISDN. AB - Two pilot telemedicine trials were established, one using basic-rate ISDN (minor injuries service) and one using primary-rate ISDN (remote fetal scanning). Preliminary results were most encouraging. In the first 10 months of operation, 49 patients with minor injuries were managed successfully using telemedicine. Preliminary calculations suggest that the use of a low-cost telemedicine link was extremely cost-effective in comparison with the cost of providing conventional medical cover. In the first six months of operation the fetal scanning link was used for 39 consultations in 29 patients. In 25 cases (86%) a definitive diagnosis was made using the telemedicine link and physical referral was avoided. However, the current cost of the required hardware (approximately 35,000 pounds per end) is likely to militate against the widespread introduction of the technique, especially since the principal savings are intangible from the perspective of any hospital considering purchase. From the point of view of its use as an information transport system for telemedicine, the ISDN proved reliable (only one failure to establish a connection on demand). Picture quality was acceptable in most cases. PMID- 9375103 TI - The SAVIOUR project: a review. PMID- 9375104 TI - The future role of telemedicine at the interface between primary and secondary care. AB - Telemedicine has been in existence for 25 years. Owing to the primitive state of technological development and poor telecommunications, early projects could not be sustained. Recent improvements in technology and communications, together with a convergence of political and economic trends, has led to a massive surge in development. In the UK one promising application is to link GPs with hospital specialists. This offers the potential for improved quality of communication, more effective use of expensive resources, and more convenient delivery of medical services to the patient. PMID- 9375105 TI - Tapping the television cable. AB - Immediate access to patient data is essential to support good clinical decision making and support. However, away from the surgery, the doctor is currently unable to have any access to the clinical database. Solutions exist to support remote access, such as modems or radio data networks, but these are slow, with typical speeds in the 2-10 kbaud region. We propose a novel solution, to use the TV cable already installed in many homes. Using this technology, a suitably equipped computer (RF modern) is capable of connecting at speeds in excess of 500 kbaud and will run applications in exactly the same way as if connected to a surgery network: the cable TV becomes a LAN, but on a metropolitan scale. Brunel University, in collaboration with the Cable Corporation, has been piloting such a network. Issues include not only levels of service, but also security on the network and access, since the data are being effectively received in every home. However, close scrutiny of channel use can create closed networks reserved for specific users. The technology involves use of an RF modem to transmit data on a reverse channel (based at 16 MHz) on each subnet to a router at the head end of the cable network. This frequency translates the packet and retransmits it to all the subnets on a forward channel (based at 178 MHz). Each channel occupies the bandwidth normally allocated to one TV channel. Access is based on a modified CSMA/CD protocol, so treating the cable network as single multiple access network. The modem comes as a standard card installed in a PC and appears much as an ethernet card, but at reduced speed. With an NDIS driver it is quite able to support almost any network software, and has successfully demonstrated Novell and TCP/IP. We describe the HomeWorker network and the results from a pilot study being undertaken to determine the performance of the system and its impact on working practice. PMID- 9375106 TI - Home health visits using a cable television network: user satisfaction. AB - There are about 1.5 million home patients who receive home health care (nurses visiting patients in their homes) in the US each year. In a significant proportion of these visits, hands-on care is not needed. Rather, the nurse needs to verify compliance with medication regimes, assess mental or emotional status, or check blood sugar levels, blood pressure and the like. Many of these activities might be handled by a nursing visit using interactive video to the patient's home, saving the nurse's time wasted in driving, finding parking, etc. A system for delivering home health care using interactive video has been piloted in the state of Kansas. Using the local cable television infrastructure for audio and video transmission, this system permits a nurse to see patients in their homes for a fraction of the cost of an on-site visit. This new method of delivering home health care is being evaluated with an ongoing study of utilization and user satisfaction. We conducted a prospective survey administered to home health nurses (n = 2) and homebound patients (n = 3) using a cable TV mediated interactive video system, to assess utilization and user satisfaction with televideo-mediated home health care visits. One hundred and eighty-one patient questionnaires and 193 nurses questionnaires were completed. The average length of a visit was 15 minutes (range 1-91). All mean scores tabulated for the questions indicated strong nurse and patient satisfaction with the system. Participating nurses and clients were satisfied with the televideo encounters. The mean score for all questions was better than neutral. Recognizing that this was a pilot study, hampered by small numbers and subject to the inherent biases of a single institution study, the results support further investigation and implementation of this modality for home health care. PMID- 9375107 TI - Networking rural and remote communities for health. PMID- 9375108 TI - The Queensland Northern Regional Health Authority telemental health project. PMID- 9375109 TI - Rural health and IT&T in Australia--the results of qualitative and quantitative surveys of the needs, perceptions and expectations of rural and remote health professionals. AB - This paper reports an initial overview of the findings of qualitative and quantitative surveys of rural and remote health professionals in Australia to determine their present use of information technology and telecommunications (IT&T), barriers to the use of IT&T, and expected future uses. The survey research commissioned for this project supports the degree of importance rural and remote health professionals attach to the introduction and use of IT&T to reduce their sense of professional isolation and to support their service provision. PMID- 9375110 TI - Outpatient teleclinics: six months' experience at the Telemedicine Centre, Sismanoglion Hospital of Athens. PMID- 9375111 TI - A review of Scottish telemedicine. AB - Telemedicine services have been provided from Scotland for many years. Initial activities centred on the provision of health care to workers on the oil installations in the North Sea, to mixed-gas divers supporting the oil industry, and to scientific staff in British Antarctic Territory. Other Scottish research work has contributed to space medicine. The remote location of much of the Scottish population is currently the reason for much telemedicine research. This paper reviews the past quarter of a century of telemedicine in Scotland and identifies the principles that have led to success in some challenging locations. The same principles can be expected to apply when telemedicine services are provided more generally. PMID- 9375112 TI - Information issues in telemedicine systems. AB - This paper examines the use of the Integrated Services Digital Network (ISDN) for telemedicine from the computer scientist's point of view. As increased bandwidth becomes available at reasonable cost, it becomes possible to employ graphical user interfaces in telemedicine systems. This means that human-computer interaction (HCI) techniques can be applied to the interface design. This paper describes some of these as applied to telemedicine by other authors. HCI techniques can be considered to be part of the development process of telemedicine systems. An integrated, multimedia-based telemedicine system which emulated the concept of a hospital information system would have many benefits, such as a consistent user interface with appropriate clinical metaphors, integrated patient records with facilities to store graphical information, and remote access. Telemedicine has much to offer in terms of providing higher standards of patient care through improved response times by clinicians who have the required information immediately available. The patient also benefits from convenience factors, such as being able to consult locally a remote specialist. PMID- 9375113 TI - Accuracy of teleradiology in skeletal disorders: solitary bone lesions and fractures. AB - To evaluate the diagnostic accuracy of digitized film radiography and digital teleradiology for detecting bone fractures and for studying solitary bone lesions, we examined 633 single radiographs from 373 patients (159 with solitary bone lesions, 123 with fractures and 91 without pathology). Radiographs were digitized using a commercial teleradiology workstation and transmitted to a local hospital over a standard telephone line. Images were reviewed by two groups of three experienced radiologists. Receiver operating characteristic (ROC) curves were analysed for conventional films, digitized images and transmitted teleradiology images. No significant differences were found among readers for the evaluation of bone fractures and solitary bone lesions. Teleradiology systems permit remote expert consultation, and telediagnosis therefore is a powerful tool in telemedicine. PMID- 9375114 TI - A survey of telepsychiatry in the USA. AB - Active telepsychiatry services in the United States were surveyed. Telepsychiatry was being used in four broad areas: educational, administrative, research, and clinical. Of the five telepsychiatry sites with accurate patient contact data, there was a mean of 1.35 patient contacts per week. The majority of telepsychiatry usage involved direct physician-patient contact. No adverse outcomes to patients were reported. PMID- 9375115 TI - A comparison of communication modes in adult psychiatry. AB - The process and outcome of clinical tasks in an acute psychiatric unit were compared using four different communication modes: face to face, telephone, hands free telephone, and a low-cost videoconferencing system. Six doctors and six patients took part in the study. Four assessment measures were used. The videoconferencing system was positively received by both patients and doctors. Both doctors and patients preferred communication modes with visual cues. However, there were few significant differences between communication modes when using single measures; only multiple levels of analysis can adequately assess the differences between such modes of communication. PMID- 9375116 TI - A telemedicine system for high-quality transmission of paper electrocardiographic reports. AB - To overcome problems associated with the faxing of ECGs, we developed a telemedicine system providing fast transmission of ECGs between physicians and cardiologists at different locations. It digitized ECGs at a resolution of 300 dots/inch (118 dots/cm), processed them, and transmitted them over a standard telephone line in under one minute. The system also paged the cardiologist in order to direct him or her to the location where the ECG would be waiting for interpretation. The system enabled physicians at remote locations to consult using voice, images and simultaneous cursor pointers. A transmitting site was set up at the Medical Centre of the Ministry of Defence and a receiving site at the National University Hospital, about 5 km away. During a six-month trial, 200 ECG reports were transmitted from one site to the other. They were rated excellent in quality by the cardiologists, being virtually indistinguishable from the originals. Our telemedicine system transmits high-quality ECGs rapidly and at low cost. PMID- 9375117 TI - A pilot study of the physician acceptance of tele-oncology. AB - During the winter of 1993, medical oncologists from an urban, university-based hospital provided oncology care to rural patients using interactive video clinics (tele-oncology). In order to assess physician satisfaction with this form of outreach, surveys were performed after the video encounters, as well as after a limited number of subsequent clinical encounters on site. Various aspects of satisfaction were evaluated. Although the sample was small (a total of 41 clinical encounters and 3 oncologists), the results suggested that there was a reasonable level of physician satisfaction with, and confidence in, the use of video to replace some on-site oncology consultations. A definitive study of tele oncology for providing care to rural cancer patients therefore appears to be warranted. PMID- 9375118 TI - Fetal telemedicine: interactive transfer of realtime ultrasound and video via ISDN for remote consultation. AB - Current referral practice for ultrasonically detected fetal abnormalities contributes to parental anxiety, inconvenience to patients, diagnostic inaccuracy, and general service inefficiency. To determine whether telemedicine would reduce these disadvantages, we established a 30-channel ISDN link between a district general hospital on an island and a subspecialty referral centre approximately 120 km away on mainland Britain. Live ultrasound images of the fetus were transmitted in realtime from a commercial scanner in the hospital using a total data transfer rate of 2 Mbit/s. After decompression at the receiving end, there was almost no perceptible loss of picture quality or frame rate. This report describes the technical aspects of the link and our preliminary experience with it. In the first two months of its operation, the link worked well and the consultants who used it found themselves confidently making diagnoses and carrying out counselling over it. If confirmed, the success of this technology has implications for future referral practice in fetal medicine. PMID- 9375119 TI - Development of a dermatological image atlas with worldwide access for the continuing education of physicians. AB - We constructed a dermatological image database as a telemedicine tool for clinical, histopathological and scientific use. The database contained about 1300 clinical images from the 40,000 slides in our archive, to provide a general overview of dermatological diseases and to cover basic student education. Some of the images were made available on the Internet through the World Wide Web system in the middle of 1994. This paper describes the architecture and components of the image database, which was designed for international access and submission of data. It allowed combined searches according to diagnosis, location and appearance of skin lesions, as well as on-screen visualization of the resulting images. PMID- 9375120 TI - Low-technology telemedicine in Antarctica. PMID- 9375121 TI - Telematics in Europe. PMID- 9375122 TI - Telemedicine in the British Antarctic Survey Medical Unit. AB - The system of telemedical care practised by the British Antarctic Survey has developed over a period of 50 years. It is a system that deals with everyday routine medical problems as well as occasional emergencies. It is tried and tested, but undergoes continual modification. Although the Antarctic stations represent a unique setting, the system has the potential for being adapted to many different situations, wherever there are small groups in remote areas needing medical backup. Initial telemedicine work conducted in the Antarctic has led to projects to improve primary care in Scottish communities some distance from specialist centres. As telecommunication links to the Antarctic stations improve, in future the lessons learnt in UK-based projects can be applied in the Antarctic. The evolutionary process will thus continue. PMID- 9375123 TI - Evaluation of a distance consulting service based on interactive video and integrated computerized technology. AB - Telemedicine equipment was installed at a rural site in Drumheller and at Calgary, 85 miles (136 km) away. It allowed consultation between health-care providers at Drumheller and specialists and subspecialists at the Faculty of Medicine in Calgary. The efficacy of the system in providing more equitable access to health care for persons living in geographically remote sites was evaluated during a 12-month pilot project. Seventy-five encounters were attempted during the study. A total of 55 encounters (42 clinical and 13 non-clinical) were completed. The completed clinical encounters were distributed across a wide spectrum of medical specialties. Users of the system reported favourably on the impact of the telemedicine system on access to health services for rural patients, on diagnostic, investigative and management decisions, on patient and physician travel times, on feelings of professional isolation and educational opportunities and on overall patient health status. The study provides new knowledge and demonstrates the success of the technology in this project. As expected, other problems were raised and addressed in a preliminary manner including: the potential for health-provider education; acquisition and retention of rural physicians; ethical, legal and patient confidentiality issues; minimum acceptable technology; and network management issues. PMID- 9375124 TI - An evaluation of the use of interactive television in an acute psychiatric service. AB - This study reports the results of the use of a low-cost videoconferencing system (LCVC) for communication in an acute psychiatric service. Qualitative research methodology was used to examine the use of the LCVC in interactions between psychiatrists, patients and nursing staff, including information on refusals. One hundred and five clinical interactions were studied over four months. The LCVC proved technically reliable and compatible with the performance of a wide range of clinical tasks. However, the results suggest the need for better understanding of the nature and origins of the attitudes that users bring to the use of such communications technology. A framework is presented for the classification of user responses in terms of preexisting attitudes of the users, technological limitations of the system and the mental state of the users. The study demonstrated the potential for interactive television to support many of the communication tasks necessary in a dispersed psychiatric service and for telepsychiatry to become a major method of service provision. PMID- 9375125 TI - A home telecare management system. AB - The increasing tendency to discharge chronic patients from hospital, as well as the growing expectation of improved quality of life for elderly and disabled people at home, was the original motivation for the development of a home telecare management system. The system allows a service centre to perform remote monitoring of biological signals and other data via the public telephone network, as well as to manage different emergency situations arising at home. The system is part of the FU-funded EPIC project (European Prototype for Integrated Care). It was tested in Belfast (Northern Ireland) and is currently being installed in Torre del Mar (Spain). This paper describes the system design and preliminary evaluation. The results indicate that the system operators find it highly acceptable in terms of efficiency, effectiveness, helpfulness, control and learnability. Integration of home telecare data with community-care information systems is essential if data captured at home are to be incorporated into the care process effectively. PMID- 9375126 TI - A teleradiology case conference system. AB - To investigate the use of teleradiology in the quality assurance programme of a multicentre radiotherapy practice, we installed image acquisition and display workstations at each of two affiliated radiation oncology clinics. A commercial diagnostic teleradiology system was successfully modified to suit the requirements of the radiotherapy subspecialty. The system allowed intersite transmission of images, access to high-resolution images from each site and, by use of laser film scanners, made accessible all types of radiation therapy image. Transmission speed and storage capacity were better than expected. Using the system, radiation oncology residents and staff reviewed 83 complex cases over eight months. Case presentation and discussion were enhanced. In the same period, 276 cases were reviewed by conference in person. Case conferences for quality assurance conducted with the teleradiology system influenced changes in treatment planning as effectively as those conducted in person. Equivalent treatment outcomes were produced. The teleradiology system facilitated quality assurance through review of patients' radiation treatments by allowing natural interactive consultation. PMID- 9375128 TI - Broadband telemedicine: teaching on the information superhighway. AB - The INSURRECT project uses the SuperJANET network to link six sites in the UK for interactive teaching and learning in surgery, an area of higher education where visual information is critical to the learning process. Collaboration between the six universities allows students access to a larger pool of surgical expertise and case studies than any single institution could provide. The project expects to improve the time that medical students can devote to surgery by up to 50%, by providing both supervised and unsupervised access to important visual information and case studies. Finally, the reduction in student numbers in operating theatres should reduce the infection risk to patients. A key component of the project is the central image resource, located in London, but allowing students and surgeons access from anywhere on the network. This paper describes the development of the interactive surgical teaching system and our experience with it during the first 18 months. One subjective observation, noticed after just one term's teaching, was the improved quality of the teaching. PMID- 9375127 TI - Experimental teleradiology. Novel telematics services using image processing, hypermedia and remote cooperation to improve image-based medical decision making. AB - We illustrate the possible impact of information technology on digital radiology using two pilot projects. The first aimed to improve the transfer of radiological information and the interaction between radiologist and referring physician, using hypermedia documents and hypermedia electronic mail. During a 12-month evaluation period, approximately 100 hypermedia reports were generated and distributed to hepatologists and neurosurgeons. The second project aimed to improve planning of orthopaedic surgery, using an image processing service for three-dimensional visualization and a conferencing system to support active cooperation. Over two months, 12 routine cases were reconstructed in three dimensions and conferencing was carried out between surgeons and radiologists in hospitals 15 km apart. Initial results were encouraging. Telematics may be valuable in reconciling the growing need for multidisciplinary cooperation with the growing geographical and organizational separation of different experts. We conclude that to benefit from information technology, the focus should not be on a direct translation of traditional working methods, but rather on possibilities that were not available in the film-based environment. PMID- 9375129 TI - Remote fetal medicine consultation using stored ultrasound video images. PMID- 9375130 TI - Three-dimensional remote imaging of surgery. PMID- 9375131 TI - Telepsychiatry in the USA. PMID- 9375132 TI - A survey of telemedicine in Italy. AB - Italy has a tradition of experimental telemedicine which dates back to the early 1970s. However, despite promising experience, widespread diffusion of telemedicine services has not occurred. The Ministry of Research recognized the potential of telemedicine for improving the quality of health care and reducing costs, and has launched a national plan for financing research and training. The plan is expected to have a major impact on the organization of telemedicine research in Italy. In this paper we describe the current situation, outline the structure of the national plan, and survey various applications in different fields, such as teleconsulting, teleradiology and telemonitoring. PMID- 9375133 TI - Network options for wide-area telesurgery. AB - Telesurgery requires a network with the following characteristics: reliability; acceptable end-to-end delay; the ability to transfer data from sources with widely different data rates; low data error rates. A wide range of network options is currently available and even more will be available shortly. It is concluded that for telesurgery ISDN is the best option at present. In the near future, as they become available commercially. ATM networks are likely to be preferable. PMID- 9375134 TI - Telemedicine for patient consultation: factors affecting use by rural primary care physicians in Kansas. AB - The purpose of our study was to investigate knowledge of, attitudes to, and use of interactive telemedicine for specialist consultation among rural practitioners Kansas. We interviewed 28 rural primary-care practitioners at seven remote health care facilities in six locations. Content analyses of the interviews showed universal but superficial knowledge of telemedicine, appreciation of the value of the technology, but relatively low usage of the telemedicine service available (32% of subjects). Physicians did not appear to be afraid of change. Telemedicine usage was not related to the professional characteristics of the physicians. Our findings suggest that further growth in the use of telemedicine will depend on efforts directed towards physicians which are aimed at creating a more user friendly environment and at accommodating the referral practices of potential users. PMID- 9375135 TI - A comparison of personal response services in Canada and the UK. AB - Personal response services operating over public telephone networks are now widespread in Western Europe and North America. They serve the needs of a million people in the UK and a further two to three million elsewhere. While most clients are elderly, the scope of such services is extending to people with support needs of all ages, especially where there are medical risks or a likelihood of falls. Such services are, therefore, on a convergent course with those concerned with telemedicine. A study of two personal response services was carried out, one based in Ottawa (Canada) and the other in Oldham (UK). The parallels and contrasts were examined through a survey involving personal interviews with samples of clients. Thirty-eight valid personal interviews were completed, 20 in Ottawa and 18 in Oldham, representing 14% and 53% respectively of all service clients in the survey areas. It is concluded that services established within the health sector (such as many in Canada) are better placed to accommodate change. Convergence with telemedicine will, as a result, be facilitated. In the UK, health authorities and trusts are likely to develop their own telemedicine services in competition with current providers of personal response services, thus delaying convergence. PMID- 9375136 TI - Improved methods for assessing information technology in primary health care and an example from telemedicine. AB - A change in evaluation methodology, from a strictly technical approach to a more comprehensive one, would result in better and less biased decision making in connection with the introduction of information technology in health care. To reach this goal, guidelines are required for building and refining contextual frames, taking qualitative considerations into account. We used primary health care as an example. A literature search produced over 200 relevant articles, from which 76 were selected which explicitly referred to evaluation in connection with health-care information systems. Text analysis allowed us to classify them into three groups. This allowed the development of a contextual frame and emphasized the human dimension as a possible problem area when using medical information systems. PMID- 9375137 TI - Teleworking in connection with technical aids for disabled persons. AB - An experimental teleworking arrangement was established between Milan and Rome in order to evaluate the use of multimedia technology and remote working for improving the service provided by an information and advice centre for the disabled. This activity requires a highly interdisciplinary approach and both clinical and technical expertise. The hypothesis was that offering the lone expert in Rome the possibility of teleconsulting with colleagues in Milan (where the whole range of expertise was available) would provide a comprehensive service for disabled clients asking for advice on technical aids in Rome. The results of an experiment demonstrated the feasibility of such teleworking and allowed a teleconsulting method to be defined that fits the specific needs of the technical aid information service and improves quality. PMID- 9375138 TI - The personal telemedicine system. A new tool for the delivery of health care. AB - An inexpensive home telemedicine system has been developed, comprising a personal telemedicine unit in the patient's home connected by ordinary telephone lines to a central nursing station. Using this system a nurse or other health-care professional at the central station was able to make a 'video visit' to the patient's home. In a preliminary trial, patients were referred by the patient's physician or by a home-care nurse. All 12 patients learned to use the personal telemedicine unit easily and effectively, and there were no complications related to its use. A significant finding was a reduction in the number of home-care visits in seven of the 12 patients (58%). Telecare using the personal telemedicine system was significantly cheaper than care delivered by conventional routes. The average charge was about $15 for a video visit by a nurse, compared with about $90 for a real visit. PMID- 9375139 TI - Development of a telemedicine and distance learning network in rural eastern North Carolina. AB - A telemedicine service was established between the East Carolina University (ECU) School of Medicine in Greenville and the Central Prison in Raleigh, about 160 km away. Based on the first two years' experience of providing a prison telemedicine service, a medical education network was set up, linking the School of Medicine to health institutions in Ahoskie, approximately 160 km away, and Jacksonville, approximately 145 km away. At about the same time, a telemedicine network was installed linking the ECU to two rural hospitals, the Roanoke-Chowan Hospital in Ahoskie, and the Martin General Hospital in Williamston, both approximately 75 km away. Although it was a demonstration project, the prison telemedicine service was thought to be cost-effective. The cost of transporting a patient from prison for medical care was estimated to be $700. In comparison, a telemedicine consultation cost about $70, excluding the equipment and network costs. During the first 33 months of operation there were over 400 telemedicine consultations carried out in eastern North Carolina. The majority were dermatology consultations, with neurology and gastroenterology being next most frequent. PMID- 9375140 TI - Home telecare for the elderly. PMID- 9375142 TI - Telemedicine in Australia. 1: The health-care system and the development of telemedicine. AB - Telemedicine developments are intimately linked to the society in which they occur. Some of the salient factors are: the structure of the health-care system, especially its funding arrangements and the relationship between hospital and community care; the telecommunications network environment and business developments in communications technology; geographic factors of distance and isolation; and government policy dealing with interacting sectors. These factors are all considered in this review of the background to telemedicine developments in Australia. PMID- 9375141 TI - Teledermatology in Scotland. PMID- 9375143 TI - The medicolegal implications of teleconsulting in the UK. AB - Broadly speaking, the medicolegal position of doctors involved in a telemedicine consultation is similar to that when telephone, fax, email or letter is used instead. All amount to the provision of advice from a distance and the normal standards of care and skill will apply. There is therefore a duty to practise to a reasonable level of skill. In a telemedicine consultation between general practitioner and hospital specialist, the referring doctor must give an accurate history (note that a video record would provide retrospective proof). For anything more than treatment purposes, the patient's permission is required before recording. There may be occasions when it is inappropriate not to use telemedicine if that is considered to be best practice in the circumstances. Time will tell whether teleconsulting is a more efficient method of practising medicine, as some people believe already. Ultimately many of the questions raised here about the medicolegal implications of such telemedicine will be determined in the courts. PMID- 9375144 TI - Teleradiology for rural hospitals: analysis of a field study. AB - We compared the accuracy of a low-cost teleradiology system with plain film at a small rural hospital. The comparison was a case-control, paired-comparison study. In total 377 consecutive cases were read prospectively by teleradiology and later by independent interpretation of the plain films. 'Truth' was determined in discrepant cases by further investigation of available records and images. Sensitivity and specificity were determined for each modality, and agreement using the kappa statistic. There was 90% agreement between teleradiology and plain film, with no significant differences. Sensitivities (0.88, 0.89) and specificities (0.98, 0.98) of the two methods were almost identical. McNemar's test indicated no significant differences in the accuracy of the two modalities. We conclude that inexpensive teleradiology for small rural hospitals is equivalent to plain film for radiologists' interpretation. PMID- 9375146 TI - A survey of a Canadian on-line substance abuse prevention initiative for adolescents and young adults. AB - Electronic Zoot is a Canadian youth-oriented, computer bulletin board system based in Edmonton. The system is designed to teach its users about the risks associated with substance use and abuse. More than 600 of Electronic Zoot's users were surveyed to obtain demographic data and information about attitudes. The majority of the users of the system were male. Most users were between 11 and 25 years of age and a disproportionately high number were from rural communities. It was found that peer support was a primary component of this telehealth service. Statistically significant age differences revealed that the system's younger users were more likely than its older users to be influenced by the drug education message of the bulletin board system. In addition, it was noted that on line surveys are easy to conduct and greatly facilitate the collection of longitudinal telehealth data. PMID- 9375145 TI - Design of a clinical data-collection form for remote health care. AB - A clinical data-collection form was designed for use in the consultation process between an astronaut and Earth. It can also be applied in most remote health-care settings. The form was tested by non-medically trained individuals in 101 simulated and 19 real cases. A completion rate of 88% was achieved, with a diagnostic accuracy of 85%. This compares favourably with studies by other workers in the field of medical decision support. Space telemedicine research will contribute to developments that will benefit not only space activities but also terrestrial applications. PMID- 9375148 TI - Remote interpretation of microbiology specimens based on transmitted still images. AB - A pilot study was carried out to examine the feasibility of the remote interpretation of microbiology specimens, that is, micro-organisms grown on agar in Petri dishes. The objective of our study was to decide whether still images contained enough information for microbiology specialists to identify the microorganisms accurately. A representative sample of microbiology specimens grown on the most commonly used agar media was used. Still images were captured using a video camera and a PC-based system. The results from a pilot study with the first video camera were discouraging, the interpretations differing in five out of 22 specimens; results with a second video camera were also disappointing. Images were then captured on photographic film, at a considerably higher resolution than images captured by the digitizer board in the PC. Again, however, the results were disappointing. We conclude that interpretation of microbiology specimens based exclusively on visual information is problematical. Remote microbiology interpretation in the future will require images of higher information content (e.g., including three-dimensional information), and will probably require additional information as well, from other senses, such as smell. PMID- 9375147 TI - Telemedicine in rural areas. Experience with medical desktop-conferencing via satellite. AB - Cooperation between physicians in hospitals in rural areas can be assisted by desktop-conferencing using a satellite link. For six weeks, medical desktop conferencing was tested during daily clinical conferences between the Virchow Klinikum, Berlin, and the Medical Academy, Wroclaw. The communications link was provided by the German Telekom satellite system MCS, which allowed temporary connections to be established on demand by manual dialling. Standard hardware and software were used for videoconferencing, as well as software for medical communication developed in the BERMED project. Digital data, such as computed tomography or magnetic resonance images, were transmitted by a digital data channel in parallel to the transmission of analogue video and audio signals. For conferences involving large groups of people, hardware modifications were required. These included the installation of a video projector, adaptation of the audio system with improved echo cancellation, and installation of extra microphones. Learning to use an unfamiliar communication medium proved to be uncomplicated for the participating physicians. PMID- 9375149 TI - Adult multilocular cyst and nephroblastomatosis. PMID- 9375150 TI - Telecommunications in endoscopy. PMID- 9375151 TI - Motor dysfunction profiles in traumatic brain injury and postconcussion syndrome. AB - Motor measures are sensitive to central lesions, but they are also affected by peripheral injury and motivation. The motor skills profiles of proven brain injury clients were compared with the profiles of healthy postconcussion patients. The chief result was a double dissociation: The traumatic brain injury (TBI) group produced a motor dysfunction gradient consistent with upper motor neuron disease, while the compensation-seeking postconcussion group produced a nonphysiologic pattern. Objective measures of behavioral pain and emotional distress did not correlate with the findings. Motor skill deficiencies in postconcussion syndrome (PCS) are probably functional in nature. PMID- 9375152 TI - Proactive inhibition and semantic organization: relationship with verbal memory in patients with schizophrenia. AB - Compared to other cognitive functions in schizophrenia, evidence suggests that verbal memory is particularly impaired. This study used the California Verbal Learning Test (CVLT) to examine proactive inhibition (PI) and semantic processing in verbal memory in 29 patients with schizophrenia and 29 healthy controls. Patients showed significantly less PI, but also did not organize (cluster) their recall according to semantic category. Controls and patients demonstrated small retroactive inhibition (RI) effects regardless of semantic content. Although both groups made similar types and numbers of free recall intrusion errors patients committed more phonemic and nonshared recognition errors. Results suggest that reduced semantic processing prevented build of PI, and contributes to defective memory in schizophrenia. The anatomic-physiologic abnormalities that underlie these findings may be particularly pronounced in prefrontal and temporal-parietal cortical areas. PMID- 9375153 TI - The impact of posttraumatic seizures on 1-year neuropsychological and psychosocial outcome of head injury. AB - This study examined the relationship of posttraumatic seizures and head injury severity to neuropsychological performance and psychosocial functioning in 210 adults who were prospectively followed and assessed 1 year after moderate to severe traumatic head injury. Eighteen percent (n = 38) of the patients experienced 1 or more late seizures (i.e., seizures occurring 8 or more days posttrauma) by the time of the 1-year followup. As expected, the head injured patients who experienced late posttraumatic seizures were those with the most severe head injuries, and they were significantly more impaired on the neuropsychological and psychosocial measures compared to those who remained seizure free. However, after the effects of head injury severity were controlled, there were no significant differences in neuropsychological and psychosocial outcome at 1 year as a function of having seizures. These findings suggest that worse outcomes in patients who develop posttraumatic seizures up to 1 year posttrauma largely reflect the effects of the brain injuries that cause seizures, rather than the effect of seizures. PMID- 9375154 TI - Comparison of neuropsychological functioning in Alzheimer's disease and frontotemporal dementia. AB - Neuropsychological changes distinguishing mild Alzheimer's disease (AD) from frontotemporal dementia (FTD) have been described, but empirical verification of differential cognitive characteristics is lacking. Archival neuropsychological data on 15 FTD patients, 16 AD patients, and 16 controls were compared. Controls outperformed both patient groups on measures of verbal and nonverbal memory, executive ability, and constructional skill, with AD patients showing more widespread memory decline. No differences were found between the 3 groups in confrontation naming, recognition memory, or basic attention. Patient groups differed only in nonverbal memory, with FTD patients performing significantly better than AD patients. However, patient groups also differed in pattern of performance across executive and memory domains. Specifically, AD patients exhibited significantly greater impairment on memory than executive tasks, whereas the opposite pattern characterized the FTD group. These findings suggest that examination of relative rankings of scores across cognitive domains, in addition to interpretation of individual neuropsychological scores, may be useful in differential diagnosis of FTD versus AD. PMID- 9375155 TI - Nonfluent progressive aphasia and semantic dementia: a comparative neuropsychological study. AB - Two patients with nonfluent progressive aphasia, who have been studied longitudinally, are contrasted with a group of 5 patients with fluent progressive aphasia or semantic dementia. The most prominent feature of the nonfluent syndrome is the severe distortion of speech output with phonological errors and agrammatic sentence structure. This contrasts with the fluent, well articulated and syntactically correct, but empty, anomic speech found in semantic dementia. Performance on tests of comprehension separates the patient groups: The nonfluent patients show normal single-word comprehension, but marked impairment on tests of syntactic comprehension, while those with semantic dementia demonstrate the opposite pattern. Category fluency is severely defective in semantic dementia, but initial letter-based fluency is more impaired in the nonfluent syndrome. Performance on nonverbally mediated tests of semantic knowledge is impaired in semantic dementia only. The 2 forms of progressive aphasia have in common the sparing of perceptual and visuospatial skills, nonverbal problem solving abilities, and day-to-day (episodic) memory. Neuroradiological investigations have shown marked selective and striking inferolateral left temporal lobe atrophy in all 5 patients with semantic dementia. The changes in nonfluent progressive aphasia appear to be less focal and involve left perisylvian structures more diffusely. These 2 forms of progressive aphasia are, we argue, distinct in their manifestations. PMID- 9375156 TI - The structure of normal human attention: The Test of Everyday Attention. AB - A range of tests of everyday attention is described, based on ecologically plausible activities such as searching maps, looking through telephone directories, and listening to lottery number broadcasts. An age-, sex- and IQ stratified sample of 154 normal participants was given these tests, along with a number of existing tests of attention. The factor structure revealed by this data set matched well contemporary evidence for a set of functionally independent attentional circuits in the brain, and included factors for sustained attention, selective attention, attentional switching and auditory-verbal working memory. The Test of Everyday Attention (TEA), which was developed and standardized on the basis of these subtests, has three parallel forms, high test-retest reliability, and correlates significantly with existing measures of attention. Furthermore, selected subtests successfully discriminate among a number of brain-impaired groups, including closed head injury versus age-matched controls, minimal versus mild Alzheimer's disease, and progressive supranuclear palsy patients versus age matched controls. PMID- 9375158 TI - Visual attention abnormalities in autism: delayed orienting to location. AB - These studies provide evidence for slowed spatial orienting of attention in autism. A group of well-defined adult autistic subjects and age-matched normal controls performed a traditional spatial cueing task in which attention-related response facilitation is indexed by speed of target detection. To address the concern that motor impairment may interfere with interpretation of response time measures in those with neurologic abnormality, we also used a new adaptation of the traditional task that depended on accuracy of response (target discrimination) rather than speed of response. This design allowed separation of time to process and respond to target information from the time to move and engage (orient) attention. Results from both tasks were strikingly similar. Normal subjects oriented attention very quickly, and showed maximal performance facilitation at a cued location within 100 ms. Autistic subjects oriented attention much more slowly and showed increasing benefits of a spatial cue with increasing cue-to-target delays. These results are consistent with previous reports that patients with autism, the majority of whom have developmental abnormalities of the cerebellum, as well as those with acquired damage to the cerebellum, are slow to shift attention between and within modalities. This paper also addresses the variability in behavioral findings in autism, and suggests that many of the apparently contradictory findings may actually reflect sampling differences in patterns of brain pathology. PMID- 9375157 TI - Effects of temporal lobe epilepsy on spatial and figural aspects of memory for a complex geometric figure. AB - The preoperative delayed memory performance on the Rey-Osterrieth Complex Figure (Lezak, 1983) of 54 patients with complex partial seizures of temporal lobe origin was analyzed using 3 different indices. One index (composite) was derived using a common scoring method that included both spatial and figural aspects of memory in its score. The other two indices were derived emphasizing either spatial or figural aspects of memory for the elements of the figure separately. All 3 indices distinguished between individuals with right-sided (RTLE) and left sided (LTLE) seizure onset. However, spatial memory was significantly lower than figural memory in individuals with RTLE as compared to those with LTLE. Both the spatial and figural memory indices were significantly lower in the presence of magnetic resonance imaging (MRI) evidence for hippocampal sclerosis in individuals with RTLE. Results suggest that while both the spatial and figural aspects of nonverbal memory are sensitive to right hippocampal dysfunction, figural memory may be less vulnerable to the effects of RTLE. PMID- 9375159 TI - Premorbid intelligence estimation and level of dementia in Alzheimer's disease. AB - Simple sight-word reading tasks have demonstrated utility in the estimation of premorbid intelligence, although the effects of progressive dementia on such tasks has not been thoroughly examined. The present investigation sought to examine estimated IQ scores from the National Adult Reading Test-Revised (NART-R; Blair & Spreen, 1989) in relation to a WAIS-R-based (Wechsler, 1981) estimate of IQ in a series of patients with probable Alzheimer's disease across varying levels of dementia. Results suggest that while NART-R scores do show a decrement with dementia severity, this decline is mild, in contrast to traditionally based IQ scores and other measures of cognitive function, which show more marked declines. Similarly, compared with other tasks, the NART-R showed the strongest correlation with education across the sample as a whole, while the other indices were more related to level of dementia. These findings support the use of measures such as the NART-R in estimating premorbid intellectual functioning in patients at various levels of dementia severity, including those with more advanced cognitive deterioration. PMID- 9375160 TI - Empirical methods for assessing meaningful neuropsychological change following epilepsy surgery. AB - Traditional methods for assessing the neurocognitive effects of epilepsy surgery are confounded by practice effects, test-retest reliability issues, and regression to the mean. This study employs 2 methods for assessing individual change that allow direct comparison of changes across both individuals and test measures. Fifty-one medically intractable epilepsy patients completed a comprehensive neuropsychological battery twice, approximately 8 months apart, prior to any invasive monitoring or surgical intervention. First, a Reliable Change (RC) index score was computed for each test score to take into account the reliability of that measure, and a cutoff score was empirically derived to establish the limits of statistically reliable change. These indices were subsequently adjusted for expected practice effects. The second approach used a regression technique to establish "change norms" along a common metric that models both expected practice effects and regression to the mean. The RC index scores provide the clinician with a statistical means of determining whether a patient's retest performance is "significantly" changed from baseline. The regression norms for change allow the clinician to evaluate the magnitude of a given patient's change on 1 or more variables along a common metric that takes into account the reliability and stability of each test measure. Case data illustrate how these methods provide an empirically grounded means for evaluating neurocognitive outcomes following medical interventions such as epilepsy surgery. PMID- 9375161 TI - Recovery of memory and executive function following anterior communicating artery aneurysm rupture. AB - We studied the recovery of memory and executive function in 10 patients following anterior communicating artery aneurysm (ACoA) rupture and repair. Patients were tested at 2 consecutive points in time following surgery (approximately at 2 and 3 months). At the first testing, the patients divided into 2 groups based on the severity of impairment on executive measures. Both groups had severe anterograde amnesia, but only patients with severe executive impairments had retrograde amnesia with a temporal gradient. At second testing, both groups had persistent severe anterograde amnesia. The dysexecutive group showed significant improvement in executive deficits and in retrograde amnesia, with attenuation of the temporal gradient. Patients with more severe executive impairments had more extensive bilateral frontal lesions than other patients. These results suggest that the cognitive profile following ACoA rupture changes with time. Time postonset following aneurysm rupture and lesion site are both critical for defining the neuropsychological profile, and determining the underlying cognitive mechanisms in this neurological disorder. PMID- 9375162 TI - Neuropsychological correlates of learning disability subtypes in children with Tourette's syndrome. AB - Neuropsychological deficits in Tourette's syndrome (TS) may be associated with learning disabilities. We examined the neuropsychological performance of 70 children with TS between the ages 6 and 18 years who were classified into four groups based on their pattern of performance on the Wide Range Achievement Test Revised. The groups included three learning disability subtypes and a nonlearning disabled comparison group. The groups differed significantly on several measures in a comprehensive neuropsychological test battery. The pattern of differences was not entirely consistent with previous research, however, suggesting that neuropsychological correlates of learning disabilities may be influenced by the specific pathophysiology associated with TS. Thus, previous research on the neuropsychology of learning disability subtypes might not be generalizable to children with discrete neuropsychiatric disorders such as TS. PMID- 9375163 TI - Spontaneous and posed facial expression in Parkinson's disease. AB - Spontaneous and posed emotional facial expressions in individuals with Parkinson's disease (PD, n = 12) were compared with those of healthy age-matched controls (n = 12). The intensity and amount of facial expression in PD patients were expected to be reduced for spontaneous but not posed expressions. Emotional stimuli were video clips selected from films, 2-5 min in duration, designed to elicit feelings of happiness, sadness, fear, disgust, or anger. Facial movements were coded using Ekman and Friesen's (1978) Facial Action Coding System (FACS). In addition, participants rated their emotional experience on 9-point Likert scales. The PD group showed significantly less overall facial reactivity than did controls when viewing the films. The predicted Group X Condition (spontaneous vs. posed) interaction effect on smile intensity was found when PD participants with more severe disease were compared with those with milder disease and with controls. In contrast, ratings of emotional experience were similar for both groups. Depression was positively associated with emotion rating but not with measures of facial activity. Spontaneous facial expression appears to be selectively affected in PD, whereas posed expression and emotional experience remain relatively intact. PMID- 9375164 TI - The influence of pattern type on children's block design performance. AB - This study sought to determine what factors contribute to normal developmental changes in performance on the block design task. The target models were systematically varied to emphasize global, intermediate, and local pattern structures. One hundred children between 4.5 and 9 years of age were tested in the first experiment. Correct performance and error types differed significantly as a function of age and pattern type. Broken configuration errors were particularly common for the global patterns. In the second experiment, 48 children between 4.5 and 8 years of age were tested using designs with a superimposed grid (cued condition). Error rates were lower in the cued condition and broken configuration errors were less frequent. These results suggest that children have more difficulty parsing more cohesive patterns, but they can modify their strategies when the square matrix is provided by the pattern structure. PMID- 9375165 TI - Effects of left-sided movements on line bisection in unilateral neglect. AB - Thirteen patients with left neglect performed line bisection under four conditions: no cue, visual cueing involving the report of a digit placed at the left end of the line, circling the left-end digit, and digit circling plus tracing of the line with the right index finger from its left end to its midpoint before bisection. Digit circling plus finger tracing was unequivocally more effective in reducing left neglect than digit circling alone, which was in turn more effective than visual cueing; indeed, digit circling with tracing completely abolished the rightward bisection bias. Thus continuously directing visuomotor control to the left side of the line (even with the right hand) until bisection is performed reduces neglect more than only requiring patients to attend to left sided visual cues. The facilitatory effects of the cueing procedures may reflect their differential efficacy in constraining as well as attracting attention and action to the left part of the target line. These findings have implications for neglect rehabilitation. PMID- 9375166 TI - Hemispheric antagonism in visuo-spatial neglect: a case study. AB - We report a case of severe visuo-spatial neglect consequent upon right-hemisphere stroke. At the time of testing, the patient had no visual field cut and no significant hemiparesis. Conventional testing on cancellation tasks with the right hand revealed reliable left neglect, but performance was significantly improved when the left hand was used. Investigations of (manual) line bisection showed normal performance with the right hand but right neglect when the left hand was used. Right neglect was also observed on a purely perceptual version of the line bisection task. We argue that the attentional vectors of the cerebral hemispheres can be modulated by (perceptual) task-demands and by (motoric) response-demands. PMID- 9375167 TI - Perceptual and premotor components of unilateral auditory neglect. AB - Recent investigations have distinguished between ophthalmokinetic and melokinetic factors of unilateral neglect. The aim of our study was to investigate the possible dissociation between melokinetic (premotor) and perceptual factors, avoiding any overt oculokinetic components. We asked four blindfolded left neglect patients to set a dichotic sound in central position, by moving a handle controlling the difference of intensity between the sounds delivered to the left and to the right ears. Two conflicting conditions were used. In the congruent condition, the sound moved in the same direction as the hand movement; in the noncongruent condition, it moved in the opposite direction. One patient performed as if suffering from melokinetic neglect, and another as if suffering from perceptual neglect. The behavior of the other two subjects did not lend itself to a clearcut interpretation. PMID- 9375168 TI - Anosognosia for hemiplegia, neglect dyslexia, and drawing neglect: clinical findings and theoretical considerations. AB - In this paper different models of anosognosia are confronted and data concerning denial behaviors are presented that were collected on a selected population of right brain-damaged patients affected by motor and neglect disorders. Anosognosia for motor impairment and anosognosia for cognitive impairments were found to be dissociated, as well as anosognosia for the upper and lower limb motor impairments. These findings are then discussed in an attempt to choose the more suitable theoretical framework for interpreting the various disorders related to denial of illness. PMID- 9375169 TI - Assessment of neglect reveals dissociable behavioral but not neuroanatomical subtypes. AB - In the current study, we investigated whether standard assessment techniques of visuospatial neglect are sensitive to detecting dissociable subtypes. We administered a battery of tasks commonly used to detect the presence of visuospatial neglect to 120 patients with unilateral right hemisphere infarcts and, in most cases, performed a systematic analysis of their lesions to quantify and localize brain damage. Using a factor analysis, we discovered seven relatively independent constructs, three of which were specifically related to the presence of left hemispatial neglect: Left Attentional Processing, Line Bisection, and Word Reading. Impairments in two of these factors, Left Attentional Processing and Line Bisection, occurred together in most cases but also occurred independently in 38 cases. There were no cases in whom Word Reading was present without concomitant deficits in one or the other two factors. These three factors could not be distinguished neuroanatomically; that is, lesions were equally likely in the temporal/parietal cortex, dorsolateral frontal cortex, or in deep frontal structures. These data confirm the notion that hemispatial neglect is a complex and multifaceted disorder composed of cognitively independent processes. These processes, however, cannot be dissociated neuroanatomically based on currently available assessment techniques. PMID- 9375170 TI - Modulation of neglect hemianesthesia by transcutaneous electrical stimulation. AB - The effects of transcutaneous electrical stimulation on deficits of tactile perception contralateral to a hemispheric lesion were investigated in 10 right brain-damaged patients and in four left brain-damaged patients. The somatosensory deficit recovered, transiently and in part, after stimulation of the side of the neck contralateral to the side of the lesion, in all 10 patients with lesions in the right hemisphere, both with (six cases) and without (four cases) left visuo spatial hemineglect, and in one left brain-damaged patient with right hemineglect. In three left brain-damaged patients without hemineglect, the treatment had no detectable effects. In one right brain-damaged patient, the stimulation of the side of the neck ipsilateral to the side of the lesion temporarily worsened the somatosensory deficit. These effects of transcutaneous electrical stimulation are similar to those of vestibular stimulation. The suggestion is made that these treatments modulate, through afferent sensory pathways, higher-order spatial representations of the body, which are pathologically distorted toward the side of the lesion. The modulatory effect is direction-specific: the defective internal representation of the contralesional side may be either partly restored, improving the disorder of tactile perception, or further impoverished, worsening the deficit. The possible neural basis of this modulation is discussed. PMID- 9375171 TI - Neuropsychological functioning in a patient with paraneoplastic limbic encephalitis. AB - A 54-year-old woman with clinically diagnosed paraneoplastic limbic encephalitis secondary to adenocarcinoma of the lung is described. Neuropsychological evaluation revealed intact visual perception, visual construction, language, speeded processing, and verbal abstract reasoning in the presence of a severe anterograde amnesia for both verbal and visual information. A profound consolidation problem is discussed in view of other diseases of the mesial temporal lobes resulting in impaired consolidation of new material. PMID- 9375172 TI - Paying attention to the Stroop effect? PMID- 9375173 TI - In memoriam Justine Saade Sergent: neuropsychologist extraordinaire March 31, 1950-April 11, 1994. PMID- 9375174 TI - An investigation of semantic space in patients with schizophrenia. AB - There has been increasing interest in the semantic cognitive system in schizophrenia. Recent findings suggest a possible breakdown of semantic information processing in this disorder. The current study attempts to further examine semantic organization in schizophrenia. Twenty-eight chronic, early-onset schizophrenic patients and 32 controls were matched for premorbid intelligence and compared in their ability to spontaneously cluster exemplars from a specific category during a fluency task. Using multidimensional scaling and clustering techniques, 11 exemplars occurring most frequently in both groups were chosen for examination of their relative "proximity" during word generation. Patients with schizophrenia showed a less stable two-dimensional organization of exemplars and were less likely to group exemplars into subordinate clusters than were normals. These results suggest that semantic networks are disorganized in these patients. These findings may have some implications for the debate over the origin of "thought disorder" in schizophrenia. PMID- 9375175 TI - Inattentive behavior after traumatic brain injury. AB - Clinicians and families report that traumatic brain injury results in a variety of attention deficits. Numerous laboratory studies have documented slowing of information processing, alteration in event-related potentials, or difficulty attending to specific relevant task dimensions in the presence of redundant information. However, little is known about how these information processing abnormalities relate to observable behaviors in daily living or work environments, which presumably form the basis for clinicians' and families' reports. We developed a quantitative assessment of behavioral inattentiveness in both quiet and distracting environments, and demonstrated excellent interrater reliability. Using this assessment, we have studied 20 patients with recent traumatic brain injury and 20 demographically comparable control subjects. We have confirmed marked differences in behavioral attentiveness between patients and controls in both distracting and nondistracting environments. PMID- 9375176 TI - The longitudinal stability of the WRAT-R Reading subtest: is it an appropriate estimate of premorbid intelligence? AB - Reading tests are assumed to be accurate estimates of premorbid intelligence, based on the belief that reading remains relatively stable following cerebral injury/disease. However, this assumption has been primarily inferred only from studies comparing differences in reading/intelligence measures between neurologically impaired and normal groups. The current study, using within subject comparisons, compared the longitudinal stability of reading (WRAT-R/3) and intelligence (WAIS-R FIQ) scores for 39 individuals with cognitive dysfunction referred for repeat neuropsychological evaluation. Wilcoxon signed ranks tests indicated that reading scores: (1) did not statistically change for those demonstrating intellectual decline (> 0 point decline in FIQ), or for those who remained relatively stable (FIQ increase between 0 and 6 points) over retest, but (2) did significantly improve for those demonstrating intellectual improvement greater than 6 points. These results suggest that reading scores may be appropriately considered as "hold" tests for individuals who intellectually decline/remain stable over time, but not for those demonstrating significant intellectual improvement. Additionally, significant variability in reading score decline/improvement suggests that caution must be used when estimating premorbid intelligence based on WRAT-R/3 Reading scores. PMID- 9375177 TI - Concurrent validity of Spanish-language versions of the Mini-Mental State Examination, Mental Status Questionnaire, Information-Memory-Concentration test, and Orientation-Memory-Concentration test: Alzheimer's disease patients and nondemented elderly comparison subjects. AB - One-hundred fifty-eight elderly Spanish-speaking U.S. residents (81 patients diagnosed with Alzheimer's disease and 77 subjects without dementia) were tested with Spanish-language versions of four brief cognitive assessment instruments: the Mini-Mental State Examination (S-MMSE), the Mental Status Questionnaire (S MSQ), the Information-Memory-Concentration test (S-IMC), and the Orientation Memory-Concentration test (S-OMC). Within-group performances were highly correlated for all four instruments. All tests distinguished between the demented and nondemented groups, but best discrimination was achieved with the S-IMC, which correctly classified 98% of subjects. This version was also the best predictor of functional disability, as measured by impairments in instrumental activities of daily living. Within the normal comparison group, neither gender nor a subject's monolingual/bilingual status affected test performance. These four Spanish-language cognitive screening tasks may aid in the evaluation of dementia among Spanish-speaking patients. PMID- 9375178 TI - Direct and indirect effects of demographic, medical, and psychological variables on neuropsychological performance in normal geriatric persons: a structural equation model. AB - The direct and indirect effects of demographic, medical, and psychological variables on neuropsychological performance in elderly individuals were examined using a LISREL structural equation model. One-hundred fifty-six geriatric subjects were individually administered a comprehensive neuropsychological battery, an extensive medical history and demographics questionnaire, and the Neuropsychology Behavior and Affect Profile (a psychological assessment instrument). The model assessed the effects of five independent latent variables (medical history, psychological functioning, global mental status, education, and gender-related functioning) on two dependent latent variables (nonverbal and verbal neuropsychological functioning). The best fitting model revealed that three latent variables (medical history, global mental status, and gender-related functioning) had direct effects on neuropsychological functioning and that all five independent variables exhibited indirect effects. These findings suggest that the influence of demographic variables on neuropsychological functioning for geriatric persons is complex and that certain variables should not be interpreted independently of each other due to their significant moderating influences. PMID- 9375179 TI - Neuropsychological functioning and determinants of morning alertness in patients with obstructive sleep apnea syndrome. AB - Neuropsychological functioning is reported to be impaired in patients suffering from obstructive sleep apnea syndrome (OSAS). This syndrome is characterized by nocturnal respiratory disturbances, blood oxygen desaturations, sleep fragmentation, and excessive daytime sleepiness. Opinions are divided concerning the exact relationship between the observed cognitive deficits, nocturnal hypoxia, sleep disruption, and impaired daytime alertness. In the present study, morning neuropsychological function of 26 moderate to severe middle-aged sleep apneics is compared to that of 22 primary insomniacs. There were no performance differences on a range of neuropsychological tests among the two patient groups. In addition, the data suggest that morning alertness impairment, which is closely associated with a lack of slow wave sleep (SWS) and rapid eye movement (REM) sleep, is of major importance in inducing poorer cognitive performance in patients with moderate to severe sleep apnea. PMID- 9375180 TI - Measures of deficit unawareness for predicted performance experiments. AB - Predicted performance experiments attempt to quantify an impaired individual's awareness of his or her deficit. These experiments measure perceived ability by the individual's prediction of his or her performance on a specific cognitive task and actual ability by his or her subsequent performance on that task. To date, the most comprehensive predicted performance experiment is the one proposed and implemented by McGlynn and Kaszniak (1991b). This experiment is potentially capable of removing a number of influences that may be confounded with deficit unawareness; however, it is not obvious what method of quantitative analysis best exploits this capability. In the present report, several possibilities are discussed. The limitations of McGlynn and Kaszniak's method are identified, and a more satisfying measure of deficit unawareness is proposed. PMID- 9375181 TI - Huntington's disease and eyeblink classical conditioning: normal learning but abnormal timing. AB - On the basis of what is known about the neural circuitry essential or normally involved in eyeblink classical conditioning (EBCC), the pattern of neurodegeneration in Huntington's disease (HD) would not appear to interfere with this type of learning. HD causes severe atrophy of the basal ganglia and thinning and shrinkage of the cerebral cortex. However, the hippocampus and hippocampal cholinergic system remain relatively intact, as does the cerebellum. Because the brain circuitry engaged in EBCC is neither lesioned nor disrupted in HD, it was predicted that HD patients would perform like normal control subjects in the 400 ms delay EBCC paradigm. Performance of seven patients with HD was compared to age matched normals, with two control subjects matched to each HD patient. There were no differences in production of conditioned responses (CRs) between HD patients and normal control subjects, but the timing of the CR was abnormal in HD. Comparisons of HD patients to patients with other neurodegenerative diseases (probable Alzheimer's disease (pAD) and Down syndrome (DS) over the age of 35 with presumed Alzheimer-like neuropathology) and to patients with cerebellar lesions demonstrated significantly better EBCC performance in HD. Results suggest that the ability to acquire CRs is normal in HD, but the striatum may have some role in optimizing the timing of the CR. PMID- 9375182 TI - Dissociable contributions of the two cerebral hemispheres to judgments of line orientation. AB - A previous study of the performance of men with chronic unilateral focal brain lesions (due to wartime missile injury) on a standard test of line orientation suggested a left hemisphere (LH) as well as a right hemisphere (RH) contribution to visuospatial processing. The present study was designed to fractionate the variables that could underlie this unexpected finding and thereby to tease out the mechanisms involved in LH as compared with RH processing. A simpler ("purer") version of the standard line orientation task was used, as were two other versions in which matching in an array and matching with distractors were measured. The findings confirmed the hypothesis of RH involvement in the purer task of metric measurement and suggested that the LH has an important role in keeping track decisions and updating decisions in more complex aspects of line orientation judgment. PMID- 9375183 TI - Reading lexically without semantics: evidence from patients with probable Alzheimer's disease. AB - Recent modifications of the lexical model of oral reading make the prediction that under conditions where sublexical reading processes alone cannot achieve the target pronunciation (i.e., when words have exceptional spellings or when sublexical processes are impaired), patients with severe semantic impairment should have more difficulty reading aloud semantically impaired words than semantically retained words. In a battery of lexical-semantic and reading tasks, two neurologically normal control subjects and two subjects with probable Alzheimer's disease (AD) and only moderate semantic impairment read aloud all words accurately. One AD subject with severe semantic impairment was impaired in word reading but demonstrated no difference in reading words with regular and exceptional spellings. Another AD subject with severe semantic impairment read aloud without error virtually all regular and exception words. Neither severely impaired AD subject demonstrated any relationship between oral reading accuracy and semantic knowledge of exception words. These findings support a model of word reading incorporating lexical, nonsemantic processes by which lexical orthographic input representations directly activate lexical phonological output representations without the necessity of semantic mediation. PMID- 9375184 TI - Feeling-of-knowing in fact retrieval: further evidence for preservation in early Alzheimer's disease. AB - The ability to retrieve and monitor factual information varying in datedness (i.e., dated vs. contemporary) was examined in healthy older adults and patients in an early phase of Alzheimer's disease (AD). Subjects were given free recall and multiple-choice recognition tests of 48 general knowledge questions. For all questions not responded to in recall, subjects made feeling-of-knowing (FOK) judgments. Results indicated dementia-related deficits in both recall and recognition, although both groups showed better recall and recognition with the dated compared with the contemporary questions. Importantly, despite deficits in fact retrieval, the AD patients showed intact monitoring of stored knowledge, as indicated by equivalent FOK accuracy for both groups. In addition, FOK accuracy was similar for the dated and the contemporary information in both groups, suggesting independence between level of general knowledge and the ability to supervise information stored in memory. PMID- 9375185 TI - Dementia associated with dorsal midbrain lesion. AB - Although the dorsal midbrain has been implicated in cognitive processes in animals, its role in humans is unclear. We report the neuropsychological and postmortem neuropathological findings of a 52-yr-old university professor who developed a profound dementia in association with a focal dorsal midbrain lesion. The patient's disorder appeared to result from a tuberculous granuloma based on the clinical course and autopsy results. Neuropsychologically, he exhibited a generalized impairment across most of the cognitive domains assessed. His deficits were not explained by impaired arousal, specific sensory or motor defects, depression, or hydrocephalus. Although there are inherent limitations to a single-case investigation, our observations are consistent with animal studies that have demonstrated that focal dorsal midbrain lesions may result in cognitive impairment. We propose that the dorsal midbrain is involved in cognitive processing via modulation of thalamocortical networks. PMID- 9375186 TI - A preliminary neuropsychological study of Persian Gulf veterans. AB - A neuropsychological investigation of 21 Persian Gulf veterans and 38 demographically matched controls was conducted in order to make a preliminary determination concerning presence of neuropsychological deficits associated with the Persian Gulf War experience. The neuropsychological test battery consisted of measures of complex attention, memory, and motor skills previously shown to be sensitive to exposure to environmental toxins. It was found that the Persian Gulf veteran group did not demonstrate substantial impairment, but an impairment index derived from 14 test variables was statistically significantly different from controls in the direction of poorer performance. PMID- 9375187 TI - Subjective complaints of cognitive symptoms are related to psychometric findings of memory deficits in patients with HIV-1 infection. AB - Eighty-five subjects at various stages of human immunodeficiency virus (HIV-1) infection and 39 seronegative controls underwent neurological and neuropsychological evaluation to assess the relationship between cognitive test results and subjective complaints (cognitive, affective, motor, and other). The effect of psychiatric disorders on the association between cognitive performance and complaints of the patients was also examined. Patients with symptomatic infection had higher frequency of complaints than subjects at asymptomatic stage. Detailed neuropsychological examination confirmed a strong association between poor verbal memory and cognitive complaints. Poor performance on cognitive speed and flexibility was associated with motor complaints and motor abnormalities. These associations were not explained by psychiatric disorders or elevated depression questionnaire scores. Our observations indicate that, especially in symptomatic HIV-1 infection cognitive changes reported by patients often reflect "objective" cognitive decline, and may be the earliest signs of HIV-1 associated cognitive disorder. No direct relationship was observed between "subjective" complaints and neuropsychological performance of asymptomatic subjects. Understanding the significance of reported cognitive changes have important therapeutic implications. PMID- 9375188 TI - Freehand drawing impairments in probable Alzheimer's disease. AB - We evaluated freehand picture production of familiar objects in patients with probable Alzheimer's disease. The overall recognizability of their drawings was significantly compromised. Error analyses revealed the production of category violations and the frequent inclusion of incorrect features in a picture that were borrowed from semantically related objects, suggesting difficulty distinguishing between items with overlapping features sets in semantic memory. Analyses of individual patient drawing profiles also revealed that some patients are disproportionately compromised in expressing a particular perceptual feature, implicating difficulty at the level of perceptual processing. Regression analyses demonstrated the contribution of limited visual attentional resources. We conclude that impaired freehand drawing in probable Alzheimer's disease is multifactorial in nature. PMID- 9375189 TI - Effect of asymptomatic carotid artery disease on cognitive outcome after cardiopulmonary bypass. AB - This prospective study reinvestigates the effect of asymptomatic carotid artery disease on the cognitive outcome after cardiopulmonary bypass (CPB) (Harrison et al., 1989). Patients (N = 104) scheduled for cardiac surgery using CPB were classified in one of two groups based on the results of a preoperative duplex B mode Doppler scan of the internal carotid arteries. All patients received a neuropsychological examination before surgery, 8 days after surgery, and 6 months after surgery (n = 79). When group data are considered, patients showed evidence of selective cognitive dysfunction early after surgery. These dysfunctions were resolved by the sixth postoperative month. We found no indications that the presence of asymptomatic carotid artery disease increased the incidence of cognitive disturbances after CPB or differentially affected the postoperative performance. We conclude that mild to moderate asymptomatic carotid artery disease does not appear to play a major role in the genesis of postoperative neuropsychological sequelae. PMID- 9375191 TI - Mood and global-local visual processing. AB - Testing hypotheses derived from neuropsychological models of mood, as well as the association of mood states and personality characteristics with global-local visual processing, were examined. Fifty-nine men completed measures associated with depression and positive mood, and were administered a brief perceptual judgment task that assessed global-local visual processing biases. Additionally, 19 of these 59 subjects were administered measures of anxiety and optimism pessimism and completed an expanded judgment task. Affective and personality variables were then correlated with judgment task performances. Consistent with predictions, positive mood and optimism were directly associated with a global bias and inversely related to a local bias. A converse pattern of findings was obtained with depression and trait anxiety. Implications for research concerning other aspects of visual processing are discussed. PMID- 9375190 TI - Representations in learning new faces: evidence from prosopagnosia. AB - We report the performance of a prosopagnosic patient on face learning tasks under different encoding instructions (i.e., levels of processing manipulations). R.J. performs at chance when given no encoding instructions or when given "shallow" encoding instruction to focus on facial features. By contrast, he performs relatively well with "deep" encoding instructions to rate faces in terms of personality traits or when provided with semantic and name information during the study phase. We propose that the improvement associated with deep encoding instructions may be related to the establishment of distinct visually derived and identity-specific semantic codes. The benefit associated with deep encoding in R.J., however, was found to be restricted to the specific view of the face presented at study and did not generalize to other views of the same face. These observations suggest that deep encoding instructions may enhance memory for concrete or pictorial representations of faces in patients with prosopagnosia, but that these patients cannot compensate for the inability to construct abstract structural codes that normally allow faces to be recognized from different orientations. We postulate further that R.J.'s poor performance on face learning tasks may be attributable to excessive reliance on a feature-based left hemisphere face processing system that operates primarily on view-specific representations. PMID- 9375192 TI - Near drowning in frigid water: a case study of a 31-year-old woman. AB - A 31-yr-old woman demonstrated intact neuropsychological functioning after being submerged for at least 30 minutes in icy cold water. Following submersion, the patient received CPR for approximately 1 hr. Eight hours after submersion, the patient's temperature was 31 degrees C (87 degrees F). She remained nonresponsive for 2 days after the accident. Extensive neuropsychological testing was completed 3 mo after the accident with no objective or subjective deficits evidenced. This case of hypothermically mediated neuroprotection from anoxia in an adult supports the need for further research on the putative neurophysiological mechanisms invoked and the potential for application of clinically induced hypothermia in the acute management of other types of cerebral insults. PMID- 9375193 TI - CT measurement of suprasellar cistern predicts rate of cognitive decline in Alzheimer's disease. AB - Previous studies reveal significant relationships between some quantitative computed tomography (CT) measures and level of cognitive functioning in patients with Alzheimer's disease (AD). This study was designed to determine whether measurements from CT scans of AD patients could predict future rates of decline in cognitive function. Subjects were 8 men and 19 women diagnosed with probable AD. CT measures included bifrontal ratio, bicaudate ratio, and areas of lateral ventricles, third ventricle, and suprasellar cistern (SSC). Measures of cognitive and adaptive functioning were obtained at the time of the scan and on follow-up. Of the CT measures, the SSCR (SSC corrected for intracranial area) was the most highly correlated with Mini-Mental State Exam (MMSE) score and other cognitive measures at the time of the scan. Follow-up data were obtained for those 20 individuals who were mildly to moderately demented at the time of the scan (MMSE > or = 10). Rate of change was calculated for each neuropsychological measure. The SSCR correlated significantly with rate of change for MMSE and other measures of cognitive and adaptive functioning. This study demonstrates that CT measurement of the SSC can predict the subsequent rate of neurocognitive decline in AD patients. PMID- 9375194 TI - Normative data stratified by age and education for the Neuropsychological Screening Battery for Hispanics (NeSBHIS): Initial report. AB - Neuropsychological assessment of monolingual Spanish-speaking people in the United States is both a common practice and an ethical dilemma. Lack of appropriate tests, the absence of norms, use of interpreters, and the multiplicity of in-house translations of commonly used measures add to the problem of accurate assessment. This paper helps address the lack of appropriate measures for the neuropsychological assessment of Latinos in the United States by providing a standardization of the Neuropsychological Screening Battery for Hispanics (NeSBHIS). Normative data on a sample of 300 Hispanic subjects stratified by gender, age, and education are provided. Current results reveal that not one measure of cognitive functioning is free from education effects. Both nonverbal measures and psychomotor speed measures were highly related to education. Age effects were noted on measures of psychomotor speed, visuospatial reasoning, and visuoconstructive skills. Gender effects were found on measures of psychomotor speed and language, with males achieving higher scores than females. The limitations of the current findings are considered. Further research for the validation of the NeSBHIS with clinical populations, as well as further normative data collection at the national and international levels, is needed. PMID- 9375195 TI - Comparative study of visual and verbal short-term memory in English and Spanish speakers: testing a linguistic hypothesis. AB - It has been proposed that differences in digit span performance between English and Spanish speakers are due to the greater number of syllables per digit in the Spanish language. To test this hypothesis, we studied the performance of 30 English- and 30 Spanish-speaking elders on the Wechsler Adult Intelligence Scale Revised (WAIS-R) Digit Span Subtest, a modified digit span test that was linguistically comparable for both languages, and the Corsi Block Test. Consistent with previous reports, we found that English speakers scored significantly higher than Spanish speakers on WAIS-R Digit Span Forward. Group differences were reduced on the modified Digit Span Forward, but remained significant. English and Spanish speakers scored comparably on Digit Span Backward (WAIS-R and modified) and Visual Span. We suggest that although differences in the number of syllables per digit string are in part responsible for the lower performance of Spanish speakers on Digit Span Forward, cultural and educational issues also contribute to the observed differences between English and Spanish speakers. PMID- 9375196 TI - The effects of divided attention on implicit and explicit memory performance. AB - This study explored the nature of the relationship between attention available at learning and subsequent implicit and explicit memory performance. One hundred neurologically normal subjects rated their liking of target words on a five-point scale. Half of the subjects completed the word-rating task in a full attention condition and the other half performed the task in a divided attention condition. Following administration of the word-rating task, all subjects completed five memory tests, three implicit (category association, tachistoscopic identification, and perceptual clarification) and two explicit (semantic-cued recall and graphemic-cued recall), each bearing on a different subset of the list of previously presented target words. The results revealed that subjects in the divided attention condition performed significantly more poorly than subjects in the full attention condition on the explicit memory measures. In contrast, there were no significant group differences in performance on the implicit memory measures. These findings suggest that the attention to an episode that is necessary to produce later explicit memory may differ from that necessary to produce unconscious influences. The relationship between implicit memory, neurologic injury and automatic processes is discussed. PMID- 9375197 TI - Neuropsychological deficits in HIV-1 seropositive and seronegative intravenous drug users (IVDUs): a follow-up study. AB - Human immunodeficiency virus type 1 (HIV-1) seropositive AIDS free and HIV-1 seronegative intravenous drug users were tested twice with a comprehensive neuropsychological test battery. Only minor group differences were found. Memory difficulties were the most pronounced difference with lower scores in the HIV-1 seropositive group. The memory difficulties were to some degree associated with emotional difficulties, that is, anxiety. The HIV-1 seropositive subjects were tested a third time and there was no further decline in any test with memory content at this testing. The only test that showed a significant decline in the HIV-1 seropositive group was the Trail Making Test. PMID- 9375198 TI - Problem solving by patients with multiple sclerosis: comparison of performance on the Wisconsin and California Card Sorting Tests. AB - Problem solving by patients with clinically definite multiple sclerosis (MS) was examined using the Wisconsin and California Card Sorting Tests (WCST and CCST). On the WCST, the MS patients achieved fewer categories and made more perseverative responses and errors than controls, confirming results of several previous studies. On the CCST, the MS patients generated and identified fewer concepts, but they performed normally when sorting was cued by the experimenter and they made no more perseverations than controls. Although findings from the WCST indicate that the problem solving deficits by MS patients closely resemble those exhibited by patients with various conditions that produce frontal lobe dysfunction, results from the CCST indicate that the problem solving difficulties exhibited by patients with MS are distinct and probably represent a primary deficit in concept formation. PMID- 9375199 TI - Interference effects in chronic alcoholism. AB - This study investigated underlying mechanisms of the verbal memory disorder associated with chronic alcoholism. Previous investigations have suggested that alcoholics are more vulnerable to interference effects on verbal learning and memory tasks, both with respect to retroactive interference (RI) and proactive interference (PI); this was the hypothesis of the current study. Measures of RI and build-up and release from PI were administered to 31 abstinent male chronic alcoholics and 24 healthy male nonalcoholic control subjects. Alcoholics demonstrated more sensitivity to RI than controls. Additionally, alcoholics displayed a more rapid build-up of PI, although they showed normal release. An increased interference effect was found to be a component of chronic alcoholics' verbal memory impairment and may differentiate chronic alcoholism from other disorders affecting verbal learning and memory. PMID- 9375200 TI - Dissociation of implicit and explicit knowledge in a case of psychogenic retrograde amnesia. AB - There have been few studies of psychogenic amnesia based on a cognitive or neuropsychological framework. In the present study, a patient with acute onset of profound psychogenic retrograde amnesia was examined. Although her performance on neuropsychological tasks revealed intact anterograde memory, language functioning, visuospatial and constructional skills, and mental speed and flexibility, she displayed severe impairments on a variety of retrograde memory tasks. Furthermore, initial observations revealed inconsistencies between the patient's recall of semantic knowledge on direct questioning and her ability to demonstrate the use of this knowledge on indirect tasks. To test this formally, we devised an indirect remote knowledge task to examine a possible dissociation between explicit and implicit memory. Two healthy subjects matched for age, gender, education, occupation, and estimated IQ were also tested. As predicted, the findings demonstrate implicit knowledge despite impaired explicit recall for the same material. PMID- 9375201 TI - The neuropsychology of mental retardation. AB - This critical review examines mental retardation (MR) from a neuropsychological perspective. Competing definitions of MR are discussed and the prevalence is estimated. Descriptions are given of idiopathic MR and the five major identifiable prenatal causes of MR: fetal alcohol syndrome, Down's syndrome, fragile X syndrome, Prader-Willi syndrome, and Angelman syndrome. Similarities and differences among syndromes are examined. Cognitive deficits common to all disorders were in attention, short-term memory, and sequential information processing, whereas language and visuospatial abilities were varied. Neuroanatomical abnormalities common to all disorders were in the hippocampus and cerebellum; individual disorders typically showed a unique pattern of other neurological abnormalities. Both knowledge of individual MR-related disorders and comparative research between disorders are important for researchers and clinicians. Further research is called for in both areas. PMID- 9375202 TI - Calculation and number processing: neuropsychological assessment and daily life difficulties. AB - One hundred unselected brain-damaged outpatients received a standardized battery of numerical tests (EC301) and, independently, a questionnaire on numerical activities in daily life (ADL). Comparisons between the two types of measurement were drawn from the scorings for different functional components of the calculation and number processing system. Results indicated high ranking correlations between the two instruments. The EC301 battery generally proved more powerful than the questionnaire in detecting the presence of mild-to-discrete impairments, but some aspects of numerical difficulties in nonaphasic patients were scored higher on the ADL questionnaire. PMID- 9375203 TI - Methodological considerations in estimating speed of cognitive operations. AB - Individuals infected with Human Immunodeficiency Virus (HIV) and having cognitive impairment have been described as having slow mentation. Data supporting this proposition come from a variety of sources, including Sternberg's (1966) item recognition memory task. The procedure nominally provides an index of speed of mental operations, independent from input/output demands. However, since the original use of this procedure in the 1960s, advances in cognitive psychology have revealed many of its limitations. The purpose of the present study was to examine the psychometric characteristics of this task. Each participant performed the Sternberg item recognition task twice, 6 mo apart. The stability of the estimate of the slope of regression equations and for zero intercept ranged from excellent (r = .87) to poor (r = .30), and the data from many individual subjects could not be reliably modelled using multiple linear regression techniques. These data, as well as those from previous research, demonstrate the limited practical use of this task in clinical samples. Furthermore, as cognitive psychological theory has advanced in the past 30 yr, the conceptual underpinnings of the procedure have essentially evaporated. PMID- 9375204 TI - Effects of bilingualism on verbal learning and memory in Hispanic adults. AB - The effect of bilingualism on qualitative aspects of verbal learning and memory was investigated. Equivalent list learning tests in English and Spanish were carefully constructed, and compared across two bilingual Hispanic groups of Mexican origin that differed in their level of English proficiency ("balanced" and "nonbalanced" bilinguals) and a group of monolingual English-speaking non Hispanic subjects. Groups were matched for age, education, and gender composition. Nonbalanced bilinguals assessed in English utilized semantic clustering to the same extent as monolinguals, but learned fewer words overall, and demonstrated lower retention scores compared to monolinguals. Comparisons of groups assessed in their dominant languages, however, revealed no significant differences on any of the learning and memory indices examined. In addition to comparisons with standard clinical memory indices, assessment issues concerning bilingual individuals are addressed. PMID- 9375205 TI - Nonspecific white matter degeneration following traumatic brain injury. AB - Morphometric analysis of magnetic resonance (MR) scans in 88 traumatic brain injury (TBI) patients demonstrated significantly larger ventricle-to-brain ratios (VBR) and temporal horn volumes, and significantly smaller fornix-to-brain ratios (FBR) and corpus callosum (CC) area measurements, compared to 73 controls. Additionally, TBI patients were grouped according to Glasgow Coma Scale (GCS) for a within-TBI sample comparison so that severity of injury on brain morphology could be examined. The severe TBI group (GCS = 3-6) differed from the mild and moderate injury groups on measures of the internal capsule, VBR, temporal horn volume, and CC. In a separate analysis wherein the TBI subjects were grouped by degree of fornix atrophy, the group with the smallest fornix size demonstrated the lowest memory performance. Furthermore, anatomic measures correlated with severity of injury, and tests of memory and motor function. Results demonstrate the diffuse nature of degeneration in TBI with more severe injury, and that quantified MR identified morphologic changes relate to neuropsychological outcome. PMID- 9375206 TI - Learning of name-face associations in memory impaired patients: a comparison of different training procedures. AB - The purpose of this study was to compare a mnemonic strategy based on concept drive processing and explicit memory (i.e., verbal elaboration and imagery) to one based on data-driven processing and implicit memory (the method of vanishing cues) in a names and faces learning task. A third training condition that used video presentation was also included. Six American and six German patients with memory impairment attributable to brain injuries of different etiologies attempted to learn the associations between names and faces in each of the three conditions. The mnemonic strategy proved to be the most effective. Discussion focuses on the characteristics of the training procedures and on the nature of the to-be-learned materials as critical determinants of the effectiveness of different training techniques. PMID- 9375207 TI - The naming impairment of living and nonliving items in Alzheimer's disease. AB - Several studies of semantic abilities in Dementia of the Alzheimer Type (DAT) suggest that their semantic disorders may affect specific categories of knowledge. In particular, the existence of a category-specific semantic impairment affecting, selectively, living things has frequently been reported in association with DAT. We report here results from two naming tasks of 25 DAT patients and two subgroups within this population. The first naming task used 48 black and white line drawings from Snodgrass and Vanderwart (1980) which controlled the visual complexity of stimuli from living and nonliving categories. The second task used 44 colored pictures (to assess the influence of word frequency in living vs. nonliving categories). Within the set of black and white pictures, both DAT patients and controls obtained significantly lower scores on high visual complexity stimuli than on stimuli of low visual complexity. A clear effect of semantic category emerged for DAT patients and controls, with a lower performance on the living category. Within the colored set, pictures corresponding to high frequency words gave rise to significantly higher scores than pictures corresponding to low frequency words. No significant difference emerged between living versus nonliving categories, either in DAT patients or in controls. In the two tasks, the two subgroups of DAT patients presented a different profile of performance and error type. As color constitutes the main difference between the two sets of pictures, our results point to the relevance of this cue in the processing of semantic information, with visual complexity and frequency also being very relevant. PMID- 9375208 TI - Working memory following improvements in articulation rate in children with cerebral palsy. AB - It has been postulated that rehearsal rate is the primary determinant of working memory capacity for verbal material (Baddeley et al., 1975). A previous study of normal control children and children with spastic diplegic cerebral palsy (SDCP) suggested that covert rather than overt rehearsal rate determines working memory capacity (White et al., 1994). In the current study, a subset of SDCP children who received a surgical treatment to relieve spasticity were retested on measures of articulation rate and memory span. A subset of control children from the original study were also retested. The SDCP group showed improvements in articulation rate at follow-up, though memory span did not change and was again equivalent to that of controls. These findings indicate that increases in articulation rate are not necessarily accompanied by improvements in memory span, and provide additional evidence that working memory capacity may be determined by covert rather than overt articulatory rehearsal. PMID- 9375209 TI - Simple reaction time as a measure of global attention in Alzheimer's disease. AB - Alzheimer's disease (AD) is characterized by progressive decline in memory, language and other cognitive functions. Deficits in attentional processes have also been suggested. A simple reaction time (RT) task was used to assess global attention in AD. The length and consistency of a warning signal given prior to the response stimulus were manipulated to determine if patients with AD and age matched controls benefit from predictability in RT tasks. Overall reaction time was slower in the AD group than in the and control group. Both groups demonstrated significant improvement in RT with long warning signals compared to short warning signals, but only the control group benefited from the consistency of the warning. PMID- 9375211 TI - One year psychosocial outcome in head injury. AB - Psychosocial outcome at one year post-injury was examined prospectively in 466 hospitalized head-injured subjects, 124 trauma controls, and 88 friend controls. The results indicate that head injury is associated with persistent psychosocial limitations. However, the presence and extent of limitations are related to the demographics of the population injured, to other system injuries sustained in the same accident, and particularly to the severity of the head injury. More severe head injuries are associated with limitations implying greater dependence on others including poorer Glasgow Outcome Scale (GOS) ratings, dependent living, unemployment, low income, and reliance on family and social subsidy systems. Head injury severity is more closely related to more objective indices of psychosocial outcome (e.g., employment) than to self-perceived psychosocial limitations, such as measured by the Sickness Impact Profile (SIP). PMID- 9375210 TI - Ecological implications of limb apraxia: evidence from mealtime behavior. AB - Humans learn skilled acts in order to effectively interact with their environment. A loss of the ability to perform skilled acts is termed apraxia. Apraxia has been thought to be of theoretical interest, but the ecological implications of apraxia are controversial and have not been fully studied. We examined ten patients with unilateral left hemisphere cerebral infarctions (eight of whom were apraxic) and compared their mealtime eating behavior to a group of neurologically normal, age-matched controls. The stroke patients were less efficient in completing the meal. They made more action errors and were less organized in the sequencing of mealtime activities. Because the patients made more errors while using tools than when performing nontool actions, their deficit could not be accounted for by an elemental motor deficit. A positive relationship was found between mealtime action errors and the severity of apraxia. These findings suggest that limb apraxia may adversely influence activities of daily living. PMID- 9375212 TI - Verbal learning and memory following pediatric closed-head injury. AB - In this study, verbal learning and memory following pediatric closed-head injuries (CHI) using the children's version of the California Verbal Learning Test (CVLT). Participants included 47 children, ages 5-16 yr, with a history of CHI, and 47 matched, noninjured controls. Children with CHI performed more poorly than controls on the CVLT, although their deficits varied qualitatively as a function of injury severity. Those with mild/moderate injuries performed as well as controls on learning trials, but they recalled proportionally fewer words after a delay (although their recognition was intact). Severely injured children demonstrated deficits in learning, delayed recall, and recognition, compared to controls. The groups did not differ in learning characteristics, but children with severe CHI exhibited more intrusions than controls. Pediatric CHI are associated with specific disturbances in verbal learning and memory similar to those of adults with CHI but different from those of children with other developmental and neurological disorders. PMID- 9375213 TI - The nature of learning and memory impairments in schizophrenia. AB - The California Verbal Learning Test was used to characterize the learning and memory impairment in schizophrenia (SC) and to evaluate potential clinical and demographic factors associated with this impairment. SC patients (n = 175) performed worse than normal comparison (NC) subjects (n = 229) on all learning, recall, and recognition memory measures. The most important clinical correlates of these impairments were earlier age of onset, more negative symptoms, and greater anticholinergic medication dosage. SC patients showed a prominent retrieval deficit as indicated by disproportionate improvement when tested in a recognition, rather than a free recall, format. A residual impairment seen with recognition testing suggests a mild encoding deficit as well. In contrast, the relative absence of a storage deficit is suggested by the lack of rapid forgetting. Using a discriminant function analysis that differentiates cortical dementia [i.e., Alzheimer's disease (AD)], subcortical dementia [i.e., Huntington's disease (HD)], and normals, it was found that 50% of the SC patients were classified as having a subcortical memory profile and 35% were classified as having a normal profile, whereas only 15% were classified as having a cortical memory profile. Although these findings reflect the clinical heterogeneity often found in SC, results suggest that most SC patients demonstrate a pattern of learning and memory impairments that resembles the pattern seen in patients with primary subcortical (specifically striatal) pathology. PMID- 9375215 TI - Semantic memory and reading abilities: a case report. AB - We document the unexpected dissociation of preserved reading skills in a patient with severely impaired semantic memory. The common co-occurrence between impairment of word meaning and surface dyslexia has not been observed. The patient (hereafter called DRN) had marked naming and word comprehension difficulties. A strong word frequency effect was observed on tests of word comprehension but was absent in a test of word reading. DRN's ability to read both regular and exception words that he failed to comprehend was remarkably well preserved. We will argue that these findings provide further support for the independence of semantic and phonological processing. PMID- 9375214 TI - Episodic memory function in advanced aging and early Alzheimer's disease. AB - Despite some well-documented differences, normal aging and Alzheimer's disease (AD) share a number of common neuropathological and neuropsychological features. Many of the reported differences are largely quantitative in nature and there is often overlap between the respective distributions of these populations. To assess the issue of overlap and distinguishing features in memory functions between these groups, and to minimize aging effects per se, samples of older individuals in good health (ages 75-95 yr) and younger patients in the early stages of AD (age < 75 yr) were selected to be similar in global cognitive functioning. Despite comparable language and visuospatial scores, these preliminary results suggest important qualitative differences in episodic memory functions between these conditions, even when "low-functioning" or "at-risk" controls are compared with early AD patients. These findings furthermore highlight some of the challenges in defining "normality" among the oldest segment of our population. PMID- 9375216 TI - A process-based view of memory. PMID- 9375217 TI - A systematic view of human memory processes. PMID- 9375219 TI - Detection of dementia of the Alzheimer type in a population-based sample: neuropsychological test performance. AB - The ability to detect dementia of the Alzheimer type (DAT) in a community dwelling sample of elderly individuals on the basis of neuropsychological test performance was examined. Three hundred sixty community-dwelling individuals were identified by neurological examination as having probable or possible Alzheimer's disease, being at risk for Alzheimer's disease, or having no cognitive impairment. A logistic model comprised of tests of verbal and nonverbal memory, mental flexibility, and confrontation naming correctly classified 82% of DAT subjects and 98% of normal elderly subjects. The logistic model classified 77% of subjects who were diagnosed as at risk for Alzheimer's disease as being cognitively normal. A cross-validation with a clinically based sample of subjects correctly classified 89% of DAT patients and 100% of normal control subjects. The results suggest that psychometric discrimination of dementia may be less accurate in community-dwelling populations than in clinically based samples. PMID- 9375218 TI - The HNRC 500--neuropsychology of HIV infection at different disease stages. HIV Neurobehavioral Research Center. AB - The present study examined neuropsychological (NP) functioning and associated medical, neurological, brain magnetic resonance imaging (MRI), and psychiatric findings in 389 nondemented males infected with Human Immunodeficiency Virus-Type 1 (HIV-1), and in 111 uninfected controls. Using a comprehensive NP test battery, we found increased rates of impairment at each successive stage of HIV infection. HIV-related NP impairment was generally mild, especially in the medically asymptomatic stage of infection, and most often affected attention, speed of information processing, and learning efficiency; this pattern is consistent with earliest involvement of subcortical or frontostriatal brain systems. NP impairment could not be explained on the bases of mood disturbance, recreational drug or alcohol use, or constitutional symptoms; by contrast, impairment in HIV infected subjects was related to central brain atrophy on MRI, as well as to evidence of cellular immune activation and neurological abnormalities linked to the central nervous system. PMID- 9375220 TI - Evidence of altered dominance in children with congenital spastic hemiplegia. AB - The study aimed at investigating lateralization effects and signs of transfer and crowding in children with congenital lateralized brain damage with the aid of a dichotic listening test, a chimeric test, and verbal and nonverbal neuropsychological tests. Thirty-three children with spastic hemiplegia and 86 control children (age 5.0-12.0 yr) were assessed. Children with left-hemisphere damage (n = 17) were found to have a pathological left-ear advantage for verbal material, and children with right-hemisphere damage (n = 16) were found to have a pathological right visual half-field advantage for visual material. Children with left-hemisphere damage and a left-ear advantage on the dichotic test were also found to have a right visual half-field advantage on the chimeric test, which was regarded as a sign of reversed dominance. No verbal or nonverbal differences emerged between the left-hemisphere and the right-hemisphere damage groups, nor did differences emerge when the children were reclassified by considering children with left hemisphere damage and signs of reversed dominance as having damage to the nondominant hemisphere. It was concluded that although lateralized brain damage may alter the dominance for verbal and visual functions, there is still considerable inter-individual variability with respect to inter- and intrahemispheric neural adjustment to damage. The dichotic and the chimeric tests did not indicate the presence of brain damage accurately, but they indicated the lateralization of damage in children with stated abnormality with a high degree (91.3%) of accuracy. PMID- 9375221 TI - The biasing effect of verbal labels on memory for ambiguous figures in patients with progressive dementia. AB - This experiment investigated the effects of verbal labels on recognition memory for ambiguous visual figures in patients with Alzheimer's disease (AD), patients with Huntington's disease (HD), and matched normal control subjects. The study employed ambiguous figures that could be interpreted in two different ways. During the study phase each figure was presented together with a verbal label that corresponded to one interpretation of the figure. After a 30-min retention interval a recognition memory test was given during which the study figures and distractor figures were presented one at a time without verbal labels. For each study figure two distractor figures were employed, each corresponding to a different interpretation of the study figure. The patients' overall recognition memory performance was severely impaired compared to control subjects. However, all subject groups tended to produce responses and response latencies to distractor items that were consistent with the verbal labels presented during the study phase. This bias effect occurred in the AD patients despite the fact that their recognition memory performance was at chance level. Indeed, there was no significant difference in the bias evidenced by the AD and HD patients and their respective matched control subjects. The bias effects were obtained in an explicit memory task, and the findings are discussed in terms of unconscious influences on explicit memory processes. PMID- 9375222 TI - Sensory- and memory-mediated olfactory dysfunction in Huntington's disease. AB - Neuropathology in Huntington's disease (HD) known to project to areas that process olfactory information raises the questions of which olfactory function, if any, is most affected in HD, and how to explain such dysfunction in terms of olfactory sensitivity and cognition. These questions were studied by comparing HD patients and controls (matched for age, gender, and education) on absolute detection, intensity discrimination, quality discrimination, short-term recognition memory, and lexical- and picture-based identification for odor. Taste or vision were used as comparison modalities. The results suggest that whereas odor-recognition memory is not affected in patients with HD, these patients have impaired olfactory functioning with respect to absolute detection, intensity discrimination, quality discrimination, and identification. The three latter impairments were significantly explained by poor detection sensitivity. Odor identification was the function most affected. PMID- 9375223 TI - Mood disturbance versus other symptoms of depression in multiple sclerosis. AB - We administered the Multiscale Depression Inventory (MDI) and the Beck Depression Inventory (BDI) to 84 multiple sclerosis (MS) patients, 101 patients diagnosed with major depression and 87 nonmedical, nonpsychiatric controls. The MDI consists of three separate depression scales measuring mood, vegetative, and evaluative symptoms. We found that: (a) MS patients did not significantly differ from the controls in mood symptoms, (b) the depression prevalence rate in MS patients was significantly lower when measured by the mood scale (17.7%) than by the BDI (30.5%) or MDI total score (26.6%), and (c) MS patients showed significantly less mood disturbance than a non-MS comparison group matched on BDI measured depression severity. We suggest that the inclusion of nonmood symptoms in self-report depression scales may artificially raise both prevalence rates and severity ratings of MS related depression and that the most valid measure of depression in MS is mood disturbance. PMID- 9375224 TI - Semantic network abnormality predicts rate of cognitive decline in patients with probable Alzheimer's disease. AB - The present study examined the relationship between rate of cognitive decline in patients with Alzheimer's disease (AD) and the integrity of the network of associations that comprise their semantic knowledge. The integrity of the semantic network of 12 AD patients was determined by comparing their networks to a standard normal control network derived with Pathfinder analysis, a multidimensional graphic analysis technique. A simple linear regression analysis, comparing the degree of semantic network deterioration with rate of cognitive decline as measured by the difference between the Dementia Rating Scale (DRS) scores obtained at the time of the testing of semantic knowledge (Year 1) and one year later (Year 2), was highly significant (r2 = .84; p < .001). These results suggest that a sensitive measure of the structural deterioration of semantic knowledge may be useful for predicting the rate of progression of cognitive changes in patients with AD. PMID- 9375226 TI - 2nd Pacific Rim Conference of the International Neuropsychological Society, and the Australian Society for the Study of Brain Impairment. Cairns, Queensland, Australia, July 5-8, 1995. Abstracts. PMID- 9375225 TI - Neuropsychological studies of asymptomatic human immunodeficiency virus-type-1 infected individuals. The HNRC Group. HIV Neurobehavioral Research Center. AB - The current review was conducted to address the ongoing debate regarding the presence or absence of neuropsychological impairment in asymptomatic HIV-Type 1 (HIV-1) seropositive individuals. Results were summarized from 57 studies that compared the performances of seropositive asymptomatic and seronegative individuals. Overall, the differences observed between median rates of impairment for asymptomatic (35%) and seronegative (12%) groups provided the clearest indication of deficits in asymptomatics. In addition, five variables were examined as possible contributors to inconsistencies found in the literature: mode of infection, test battery type, test battery size, sample size, and method of data analysis. Of these variables, only mode of infection and test battery size appeared to substantially influence the outcome of the studies reviewed with regard to identifying neuropsychological impairment in asymptomatics. PMID- 9375227 TI - 22nd Annual Meeting of the International Neuropsychological Society. Cincinnati, Ohio, February 2-5, 1994. Abstracts. PMID- 9375228 TI - Normal perceptual priming of orthographically illegal nonwords in amnesia. AB - This study examined priming in perceptual identification of orthographically illegal nonwords in control subjects and patients with global amnesia. Subjects studied a list of orthographically illegal nonwords and then performed a perceptual identification task in which half of the stimuli were from the prior study list and half were new (unstudied) stimuli. Priming was reflected in enhanced identification accuracy of studied compared to unstudied nonwords. Amnesic patients showed significant and normal priming despite impaired recognition memory performance. Because the experimental stimuli were dissimilar to real words in terms of orthography and phonology, it is unlikely that this priming effect was mediated by activation of pre-existing representations of orthographically or phonologically similar words, morphemes, or syllables. These results demonstrate that intact perceptual priming in amnesia is not limited to stimuli that are premorbidly represented in long-term knowledge, nor to novel stimuli that conform to the rules that characterize familiar items. Further, because the experimental stimuli comprised novel letter assemblies, the results suggest that amnesic patients can show normal priming for new perceptual associations. These findings demonstrate that processes spared in amnesia can support the creation and subsequent retrieval of novel stimulus representations. PMID- 9375229 TI - Implicit memory in amnesic patients: when is auditory priming spared? AB - Amnesic patients often exhibit spared priming effects on implicit memory tests despite poor explicit memory. In previous research, we found normal auditory priming in amnesic patients on a task in which the magnitude of priming in control subjects was independent of whether speaker's voice was same or different at study and test, and found impaired voice-specific priming on a task in which priming in control subjects is higher when speaker's voice is the same at study and test than when it is different. The present experiments provide further evidence of spared auditory priming in amnesia, demonstrate that normal priming effects are not an artifact of low levels of baseline performance, and provide suggestive evidence that amnesic patients can exhibit voice-specific priming when experimental conditions do not require them to interactively bind together word and voice information. PMID- 9375230 TI - Knowledge of New English vocabulary in amnesia: an examination of premorbidly acquired semantic memory. AB - To assess if amnesics have intact remote memory for general semantic information, we examined memory for vocabulary words with known dates of entry into the language between 1955 and 1989. Amnesics of mixed etiology with acute onset performed normally on both a recall and a recognition task. Korsakoff patients, in contrast, were impaired on both tasks and demonstrated a gradient such that their knowledge of words acquired during more recent time periods was worse than that of words acquired during more remote time periods. The improvement in performance associated with recognition testing was larger for Korsakoff patients than for control subjects and correlated significantly with a composite measure of frontal dysfunction. These findings suggest a deficit in the controlled search and retrieval of semantic information in Korsakoff patients. The implications of the differential performance of Korsakoff and mixed etiology amnesics for explanations of temporally graded retrograde amnesia are discussed. PMID- 9375231 TI - Memory for novel and familiar spatial and linguistic temporal distance information in hypoxic subjects. AB - Hypoxia is known to cause damage to the hippocampus as well as memory impairments in humans. Subjects who have experienced a hypoxic episode and age-, gender-, and education-matched control subjects were tested for memory for spatial and linguistic temporal distance information using sentences and spatial locations. Each test contained a familiar component based on information that is meaningful and is thought to be stored as part of the knowledge system (prior knowledge) as well as a novel component based on new information. Subjects were presented a list of eight-word sentences or eight spatial locations (Xs) on a grid on a Macintosh computer and tested for memory for temporal distances. Temporal distance is defined as the number of items that occur between the two test items, in the study phase. Compared to control subjects, hypoxic subjects were impaired across all temporal distances on the novel spatial and linguistic tasks. As the temporal distance increased, hypoxic subjects showed some improvement in memory performance. In addition, memory of familiar temporal distance information was also assessed. Hypoxic subjects were impaired, compared to control subjects, for familiar temporal distance information. For hypoxic subjects there was a proportionally greater impairment for novel compared to familiar spatial and linguistic temporal distance information. There was a significant difference in their performance on the familiar temporal distance tasks compared to their performance on the novel tasks. Prior knowledge appears to attenuate the deficits seen in the familiar temporal distance tasks. It appears that hypoxia may cause more selective damage to the hippocampus and this damage is sufficient to produce profound memory impairments for primarily novel and less severe memory impairments for familiar spatial and linguistic temporal distance information. PMID- 9375232 TI - Assessment of familiarity and recollection in the false fame paradigm using a modified process dissociation procedure. AB - A modified way of administering the process dissociation procedure to the false fame paradigm is described. Multidimensional signal detection theory (SDT) is used to correct for recollection as well as familiarity false alarms, and two experiments are reported that compare this method of false alarm correction with the hybrid procedure preferred by Jacoby et al. (1993). In experiment 1, it is shown that recollection and familiarity are lost at the same rate in normal subjects over a delay of 1 d when an SDT analysis is used. Analysis with the hybrid procedure fails to find any forgetting over the 1-d delay. In experiment 2, amnesics are shown to have preserved familiarity in the face of impaired recollection for names when the results are analyzed by either method. An additional analysis showed that the amnesics' familiarity was normal even for relatively novel surnames. The SDT analysis also revealed that the amnesics, relative to controls, showed a conservative recollection and a liberal familiarity response bias. The results indicate that it is important to correct for recollection as well as familiarity false alarms. PMID- 9375233 TI - Aging, encoding specificity, and memory change in the Double Memory Test. AB - Aged and young adults were tested by category cued recall after learning with category cues (CCR) or with item cues (ICR). CCR was about twice ICR for both aged and young adults. The aged recalled less than the young and did not benefit as much from greater encoding specificity and deeper processing in CCR. ICR and CCR were correlated, so that expected CCR can be predicted from ICR. The regression of CCR on ICR was linear for young adults, but was piecewise linear for the aged, showing that the relationship between ICR and CCR was not uniform for the aged adults. Lower than expected CCR by a subset of aged without clinical dementia may be a sign of preclinical dementia. PMID- 9375234 TI - Bilingual effects of unilingual neuropsychological treatment of dyslexic adolescents: a pilot study. AB - Fourteen young adolescents with specific reading disabilities received short term neuropsychological treatment--specifically left hemisphere (LH) or right hemisphere (RH) stimulation--in a clinical pilot project. The effects on single word and passage reading were evaluated when the language of treatment was either Dutch (mother tongue) or English (foreign language). Transfer effects across the two languages were also studied. In general, the results indicate that these short term interventions may prove successful for the treated language and with the additional transfer to a second (not treated) language. PMID- 9375235 TI - Severe anoxia with and without concomitant brain atrophy and neuropsychological impairments. AB - Significant anoxia may cause a variety of neuropathologic changes as well as cognitive deficits. We have recently seen 3 patients who have suffered severe anoxic episodes all with initial Glasgow Coma Scores (GCS) of 3 with sustained coma for 10-14 d. All 3 patients had extended hospitalizations and rehabilitation therapy. A neuropsychological test battery was administered and volumetric analyses of MRI scans were carried out in each case at least 6 mo postinjury. Two of the patients display distinct residual cognitive and neuropathologic changes while 1 patient made a remarkable recovery without evidence of significant morphological abnormality. These three cases demonstrate, that even with similar admission GCS, the outcome is variable and the degree of neuropsychological impairment appears to match the degree of morphologic abnormalities demonstrated by quantitative MR image analysis. An important finding of this study is that even though subjects with an anoxic insult exhibit severe cognitive and memory impairments along with concomitant morphologic changes, their attention/concentration abilities appear to be preserved. MR morphometry provides an excellent means by which neural structural changes can be quantified and compared to neuropsychological and behavioral outcomes. PMID- 9375236 TI - Intellectual perestroika and Russian neuropsychology. PMID- 9375237 TI - Executive function in children with Tourette syndrome and/or attention deficit hyperactivity disorder. AB - Tourette Syndrome (TS) in children is associated with various neurobehavioral disorders including attention deficit hyperactivity disorder (ADHD). Children with TS and ADHD show some difficulties with neuropsychological tasks, but we do not know if children with TS alone have neuropsychological deficits. To assess specific cognitive differences among children with TS and/or ADHD, we administered a battery of neuropsychological tests, including 10 tasks related to executive function (EF), to 10 children with TS-only, 48 with ADHD-only, and 32 with TS + ADHD. Children in all groups could not efficiently produce output on a timed continuous performance task [Test of Variables of Attention (TOVA) mean reaction time and reaction time variability]. Children with TS-only appeared to have fewer EF impairments and significantly higher perceptual organization scores than children with TS + ADHD or ADHD-only. These findings suggest that deficiencies in choice reaction time and consistency of timed responses are common to all three groups, but children with TS-only have relatively less EF impairment than children with TS + ADHD or ADHD-only. PMID- 9375238 TI - A longitudinal study of reading ability in patients suffering from dementia. AB - The aim of this study was to investigate whether reading is a preserved ability in patients suffering from dementia, as was first suggested by Nelson and McKenna (1975). The 57 patients included in the study had possible or probable Alzheimer's disease or similar degenerative conditions and were assessed longitudinally. Their performance on the National Adult Reading Test [(NART); Nelson, 1982, 1991] is compared to that on a shortened version of the WAIS-R. It is found that although performance on the NART does decline gradually over time, the deterioration on formal tests of IQ is more rapid and more severe. It seems that the decline in reading across the group is due to those patients who have a lower verbal IQ (VIQ) than performance IQ (PIQ). It is concluded that generally the NART can be used as a predictor of the premorbid intellectual functioning of a patient with dementia, given that the VIQ is greater than PIQ. PMID- 9375239 TI - Frontal lobe damage produces episodic memory impairment. AB - This article reports the outcome of a meta-analysis of the relation between the frontal lobes and memory as measured by tests of recognition, cued recall, and free recall. We reviewed experiments in which patients with documented, circumscribed frontal pathology were compared with normal control subjects on these three types of tests. Contrary to conventional wisdom, there is strong evidence that frontal damage disrupts performance on all three types of tests, with the greatest impairment in free recall, and the smallest in recognition. PMID- 9375240 TI - Performance on the Tower of London test after severe head injury. AB - Efficient solution of the Tower of London (T of L) test (Shallice, 1982) has been hypothesized to depend on frontal lobe mediation. Performance on the test by 20 patients with severe, diffuse, traumatic head injury was compared with that of control subjects, matched on age and years of education, and, within the patient group, according to broad location of damage (frontal or nonfrontal). Scores were also compared with those obtained on two commonly used tests of frontal lobe function, Verbal Fluency, and the Wisconsin Card Sorting test (WCST). Results indicated that whereas the Verbal Fluency test and WCST discriminated well between patients and control subjects, the T of L test did not, nor did it discriminate well between patients with and without documented frontal lobe damage. However, there were large individual differences in planning and solution times across all subjects. Interpretation of results was complicated by interaction of other variables such as premorbid IQ and duration of posttraumatic amnesia. It is suggested that closer attention to the relation between planning and total times separately for correct and incorrect solutions might be informative. A need for systematic study of the relationship between test performance and everyday behavior is also identified. PMID- 9375241 TI - Cognitive flexibility and complex integration in Parkinson's disease, Huntington's disease, and schizophrenia. AB - Two new tasks designed to individualize and assess aspects of cognitive flexibility and complex integration were administered to patients with schizophrenia (n = 16), Parkinson's disease (PD; n = 25) and Huntington's disease (HD; n = 12). Findings indicated impaired performance in the schizophrenic and HD groups on components of solution fluency, reactive flexibility and integration. The PD group demonstrated normal performance on all but the solution fluency and reaction time measures. These findings corroborate previous studies suggesting that executive and problem solving disturbances feature in schizophrenia and HD and that these functions may not be as severely affected in medicated PD. Slowed reaction time by both dementia groups is explained with reference to the concept of bradyphrenia. PMID- 9375242 TI - Right hemisphere mediation of verbal learning and memory in acquired right hemisphere speech dominant patients. AB - Forty-eight patients with temporal lobe epilepsy completed measures of narrative recall and list learning prior to surgery. The intracarotid amytal procedure (IAP) established that 13 patients were right hemisphere dominant for speech and 35 (18 left foci, 17 right foci) were left hemisphere dominant. Hippocampal volumetric neuron densities were measured after surgery. The left hippocampal neuron densities in subfields CA3 and the hilar area were significantly correlated with list learning ability and percent retention for narrative recall only for left hemisphere speech dominant patients with left seizure foci. No significant correlations between measures of neuron volume and memory were found for the left hemisphere speech dominant patients with right seizure foci or the right hemisphere speech dominant patients with left seizure foci. This suggests that the right hemisphere of right speech dominant patients mediates verbal memory as well as speech. This conclusion is supported by patterns of correlations among measures of verbal memory that differed for patients undergoing resection of the dominant hemisphere versus those undergoing resection of the nondominant hemisphere. However, it is premature to conclude that the cerebral organization of cognitive functions of right hemisphere speech dominant patients is equivalent albeit reversed from that of left hemisphere speech dominant patients. Right hemisphere speech dominant patients with left temporal foci differed from left hemisphere speech dominant patients with right temporal foci with respect to the patterns of correlations between measures of verbal memory and intelligence as well as the level of intellectual ability that they demonstrated. PMID- 9375243 TI - Comparison of figural intrusion errors in three amnesic subgroups. AB - To examine the contribution of memory deficits and executive dysfunction to the production of prior-item intrusion errors, Korsakoff, mesial temporal amnesic, and anterior communicating artery aneurysm (ACoA) patients' performance on the Visual Reproduction subtest of the Wechsler Memory Scale-Revised (WMS-R) was assessed. The Korsakoff patients were matched to the mesial temporal group in terms of severity of amnesia, while the ACoA group, which was less severely amnesic, was matched to the Korsakoff group in their performance on executive tests. Results indicated that at immediate recall, Korsakoff patients made significantly more intrusions than mesial temporal and ACoA patients. Conversely, after a delay, ACoA patients tended to make more intrusions than the other groups. Findings suggest that intrusions are due to a combination of deficient memory and executive dysfunction. A further comparison of a subgroup of ACoA patients matched to the Korsakoff patients in terms of severity of amnesia, however, revealed differences in the pattern of intrusions of these two groups, suggesting that different mechanisms may underlie Korsakoff and ACoA patients' susceptibility to interference. PMID- 9375244 TI - Semantic relations and Alzheimer's disease: an early and disproportionate deficit in functional knowledge. AB - This experiment explored knowledge of four types of semantic relations (superordinate category, part, property, and function) in Alzheimer's disease (AD) subjects and age- and education-matched controls. Moderate AD subjects showed the greatest disruption on functional relations, intermediate disruption on part and property relations, and the least disruption on category relations; mild AD subjects showed a similar pattern but significant deficits only on functions. We suggest that the disproportionate deficit on functions reflects a greater cognitive complexity of functions than other semantic relations that renders them more vulnerable either to disrupted processing or to structural degradation of the network of associations among semantic concepts. PMID- 9375245 TI - Delayed recognition memory span in HIV-1 infection. AB - We administered a spatial version of the Delayed Recognition Span Test (DRST), a working memory task performed abnormally by patients with basal ganglia disease, to a group of 96 HIV-seropositive and 83 seronegative subjects with a high prevalence of substance abuse. For comparison purposes, we also administered the Symbol-Digit Modalities Test (SDMT) and the Trail Making Test (TMT), measures which detect HIV-related mental slowing efficiently in gay men but are nonspecifically impaired in subjects with a history of substance abuse. As predicted, scores on the TMT and the SDMT did not discriminate the groups, but HIV-seropositive subjects had significantly shorter spatial spans (p < .007) and DRST total scores (p < .005). These effects could not be attributed to differences in age, education, estimated intelligence, or psychological distress, because the groups were well matched on these variables. The DRST is a promising measure of HIV-related cognitive dysfunction in substance abusers, who are often nonspecifically impaired on psychomotor tasks. These preliminary data also indicate that working memory function should be studied further in HIV seropositive subjects. PMID- 9375246 TI - Relationship between psychiatric disease and neuropsychological impairment in HIV seropositive individuals. AB - Neuropsychological impairment and DSM-III-R Axis I psychiatric diagnoses were evaluated in a heterogenous group of HIV seropositive individuals and seronegative individuals with similar risk factors for HIV infection. Neuropsychological and psychiatric disorders were common in the HIV seropositive group, but there were no relationships between these two aspects of neuropsychiatric dysfunction in seropositive patients. Results indicate that psychiatric disorders in HIV seropositive individuals tend to predate infection and decrease over time following knowledge of seroconversion, suggesting that they are primarily a function of psychosocial factors. Neuropsychological disorders are specific to HIV seropositive patients and tend to increase over time following seroconversion, suggesting that they are due to neurological effects of HIV-infection. PMID- 9375247 TI - Developmental disturbance of access to biographical information and people's names: a single-case study. AB - The paper describes the case of a person (GB) without any clinical evidence of cerebral disease who showed a specific impairment in the retrieval of biographical information, including names, about famous people. This deficit appeared while GB scored normally in different long-term memory tasks, and in object naming tasks. Moreover, he showed no impairment in the structural encoding and the recognition of faces. His specific impairment is interpreted both in terms of Bruce and Young's (1986) functional model of person recognition and in terms of the more recent Burton et al. (1990) interactive activation version of the Bruce and Young model. PMID- 9375248 TI - Can prenylcysteines be exploited as ligands for mammalian multidrug-resistance transporters? AB - The overexpression of specific transport proteins in the membrane of many cancer cells renders these cells resistant to many therapeutic drugs. Some lipid modified cysteine compounds inhibit one drug-transporting protein, indicating the potential of developing such compounds as therapeutic agents. PMID- 9375249 TI - Site-specific recombination caught in the act. PMID- 9375250 TI - Structural studies of natural product biosynthetic proteins. AB - The first high-resolution structures of key proteins involved in the biosynthesis of several natural product classes are now appearing. In some cases, they have resulted in a significantly improved mechanistic understanding of the often complex processes catalyzed by these enzymes, and they have also opened the way for more rational efforts to modify the products made. PMID- 9375251 TI - Micropatterning gradients and controlling surface densities of photoactivatable biomolecules on self-assembled monolayers of oligo(ethylene glycol) alkanethiolates. AB - BACKGROUND: Bioactive molecules that are covalently immobilized in patterns on surfaces have previously been used to control or study cell behavior such as adhesion, spreading, movement or differentiation. Photoimmobilization techniques can be used, however, to control not only the spatial pattern of molecular immobilization, termed the micropattern, but also the surface density of the molecules--a characteristic that has not been previously exploited. RESULTS: Oligopeptides containing the bioactive Arg-Gly-Asp cell-adhesion sequence were immobilized upon self-assembled monolayers of an oligo(ethylene glycol) alkanethiolate in patterns that were visualized and quantified by autoradiography. The amount and pattern of immobilized peptide were controlled by manipulating the exposure of the sample to a UV lamp or a laser beam. Patterns of peptides, including a density gradient, were used to control the location and number of adherent cells and also the cell shape. CONCLUSIONS: A photoimmobilization technique for decorating surfaces with micropatterns that consist of variable densities of bioactive molecules is described. The efficacy of the patterns for controlling cell adhesion and shape has been demonstrated. This technique is useful for the study of cell behavior on micropatterns. PMID- 9375252 TI - Site-specific incorporation of biotinylated amino acids to identify surface exposed residues in integral membrane proteins. AB - BACKGROUND: A key structural issue for all integral membrane proteins is the exposure of individual residues to the intracellular or extracellular media. This issue involves the basic transmembrane topology as well as more subtle variations in surface accessibility. Direct methods to evaluate the degree of exposure for residues in functional proteins expressed in living cells would be highly valuable. We sought to develop a new experimental method to determine highly surface-exposed residues, and thus transmembrane topology of membrane proteins expressed in Xenopus oocytes. RESULTS: We have used the in vivo nonsense suppression technique to incorporate biotinylated unnatural amino acids into functional ion channels expressed in Xenopus oocytes. Binding of 125I streptavidin to biotinylated receptors was used to determine the surface exposure of individual amino acids. In particular, we studied the main immunogenic region of the nicotinic acetylcholine receptor. The biotin-containing amino acid biocytin was efficiently incorporated into five sites in the main immunogenic region and extracellular streptavidin bound to one residue in particular, alpha 70. The position of alpha 70 as highly exposed on the receptor surface was thus established. CONCLUSIONS: The in vivo nonsense suppression technique has been extended to provide the first in a potential series of methods to identify exposed residues and to assess their relative exposure in functional proteins expressed in Xenopus oocytes. PMID- 9375253 TI - Folding of the polyketide chain is not dictated by minimal polyketide synthase in the biosynthesis of mithramycin and anthracycline. AB - BACKGROUND: Mithramycin, nogalamycin and aclacinomycins are aromatic polyketide antibiotics that exhibit antitumour activity. The precursors of these antibiotics are formed via a polyketide biosynthetic pathway in which acetate (for mithramycinone and nogalamycinone) or propionate (for aklavinone) is used as a starter unit and nine acetates are used as extender units. The assembly of building blocks is catalyzed by the minimal polyketide synthase (PKS). Further steps include regiospecific reductions (if any) and cyclization. In the biosynthesis of mithramycin, however, ketoreduction is omitted and the regiospecificity of the first cyclization differs from that of anthracycline antibiotics (e.g. nogalamycin and aclacinomycins). These significant differences provide a convenient means to analyze the determinants for the regiospecificity of the first cyclization step. RESULTS: In order to analyze a possible role of the minimal PKS in the regiospecificity of the first cyclization in polyketide biosynthesis, we expressed the mtm locus, which includes mithramycin minimal PKS genes, in Streptomyces galilaeus, which normally makes aclacinomycins, and the sno locus, which includes nogalamycin minimal PKS genes, in Streptomyces argillaceus, which normally makes mithramycin. The host strains are defective in the minimal PKS, but they express other antibiotic biosynthesis genes. Expression of the sno minimal PKS in the S. argillaceus polyketide-deficient strain generated mithramycin production. Auramycins, instead of aclacinomycins, accumulated in the recombinant S. galilaeus strains, suggesting that the mithramycin minimal PKS is responsible for the choice of starter unit. We also describe structural analysis of the compounds accumulated by a ketoreductase deficient S. galilaeus mutant; spectroscopic studies on the major polyketide compound that accumulated revealed a first ring closure which is not typical of anthracyclines, suggesting an important role for the ketoreductase in the regiospecificity of the first cyclization. CONCLUSIONS: These experiments clearly support the involvement of ketoreductase and a cyclase in the regiospecific cyclization of the biosynthetic pathway for aromatic polyketides. PMID- 9375254 TI - Molecular recognition of diketide substrates by a beta-ketoacyl-acyl carrier protein synthase domain within a bimodular polyketide synthase. AB - BACKGROUND: Modular polyketide synthases (PKSs) are large multifunctional proteins that catalyze the biosynthesis of structurally complex bioactive products. The modular organization of PKSs has allowed the application of a combinatorial approach to the synthesis of novel polyketides via the manipulation of these biocatalysts at the genetic level. The inherent specificity of PKSs for their natural substrates, however, may place limits on the spectrum of molecular diversity that can be achieved in polyketide products. With the aim of further understanding PKS specificity, as a route to exploiting PKSs in combinatorial synthesis, we chose to examine the substrate specificity of a single intact domain within a bimodular PKS to investigate its capacity to utilize unnatural substrates. RESULTS: We used a blocked mutant of a bimodular PKS in which formation of the triketide product could occur only via uptake and processing of a synthetic diketide intermediate. By introducing systematic changes in the native diketide structure, by means of the synthesis of unnatural diketide analogs, we have shown that the ketosynthase domain of module 2 (KS2 domain) in 6 deoxyerythronolide B synthase (DEBS) tolerates a broad range of variations in substrate structure, but it strongly discriminates against some others. CONCLUSIONS: Defining the boundaries of substrate recognition within PKS domains is crucial to the rationally engineered biosynthesis of novel polyketide products, many of which could be prepared only with great difficulty, if at all, by direct chemical synthesis or semi-synthesis. Our results suggest that the KS2 domain of DEBS1 has a relatively relaxed specificity that can be exploited for the design and synthesis of medicinally important polyketide products. PMID- 9375255 TI - Accessing rare activities from random RNA sequences: the importance of the length of molecules in the starting pool. AB - BACKGROUND: In the past few years numerous binding and catalytic motifs have been isolated from pools of random nucleic acid sequences. To extend the utility of this approach it is important to learn how to design random-sequence pools that provide maximal access to rare activities. In an effort to better define the relative merits of longer and shorter pools (i.e. pools with longer or shorter random-sequence segments), we have examined the inhibitory effect of excess arbitrary sequence on ribozyme activity and have evaluated whether this inhibition overshadows the calculated advantage of longer pools. RESULTS: The calculated advantage of longer sequences was highly dependent on the size and complexity of the desired motif. Small, simple motifs were not much more abundant in longer molecules. In contrast, larger motifs, particularly the most complex (highly modular) motifs, were much more likely to be present in longer molecules. The experimentally determined inhibition of activity by excess sequence was moderate, with bulk effects among four libraries ranging from no effect to 18 fold inhibition. The median effect among 60 clones was fivefold inhibition. CONCLUSIONS: For accessing simple motifs (e.g. motifs at least as small and simple as the hammerhead ribozyme motif), longer pools have little if any advantage. For more complex motifs, the inhibitory effect of excess sequence does not approach the calculated advantage of pools of longer molecules. Thus, when seeking to access rare activities, the length of typical random-sequence pools (< or = 70 random positions) is shorter than optimal. As this conclusion holds over a range of incubation conditions, it may also be relevant when considering the emergence of new functional motifs during early evolution. PMID- 9375256 TI - Cancer gets the red light. Pharmacyclics, Inc. PMID- 9375257 TI - Performance of the Composite International Diagnostic Interview Short Form for major depression in community and clinical samples. AB - The CIDI Short Form is a brief survey instrument designed to identify episodes of major depression. The instrument was developed for inclusion in the US National Health Interview Survey, but has also been used in the Canadian National Population Health Survey (NPHS). In this study, data deriving from use of the CIDI Short Form in the NPHS are compared to published data from the Mental Health Supplement of the Ontario Health Survey, which utilized a fully validated structured interview: the Composite International Diagnostic Interview (CIDI). In an additional analysis, the sensitivity and specificity of the Short Form were evaluated in relation to the full CIDI mood disorders section in a clinical sample of 122 psychiatric in-patients. Relative to published data from the Ontario Health Survey, application of the CIDI Short Form in the NPHS resulted in an overestimation of major depression prevalence by approximately 50%. In the clinical sample, the CIDI Short Form was highly sensitive (98.4%), but not highly specific (72.7%). Active medical conditions, substance use disorders and dysthymia were frequently observed among subjects with false positive CIDI Short Form ratings. The CIDI Short Form appears to overestimate the 12-month period prevalence of major depression when it is applied in community samples. Since the Short Form does not make exclusions for organically induced symptoms, it is probable that some subjects with depressive symptoms secondary to physical illnesses and/or drug exposures score above the instrument's threshold, perhaps leading to an elevation in period prevalence rates. PMID- 9375258 TI - Uses and limitations of routine hospital admission/separation records for perinatal surveillance. AB - This study examined the quality of data for delivering mothers and their newborns (April 1, 1984 to March 31, 1995) recorded by the Canadian Institute for Health Information (CIHI). The number of illogical and out-of-range values in the CIHI data were quite few; the occurrence of maternal and infant diseases estimated from CIHI data was quite similar to that in the literature; and major medical/obstetric complications recorded in CIHI were, in general, good predictors of adverse pregnancy outcomes. The authors conclude that CIHI data contain some of the information pertinent to perinatal surveillance that may be used to monitor maternal and infant health and to assess intrapartum care and hospital resource utilization. To adequately monitor and analyze patterns of health determinants and outcomes in all pregnant women and their infants in Canada, additional data collection mechanisms are needed to cover all recognized pregnancies and to collect antenatal and postpartum information and more detailed information on intrapartum care. PMID- 9375259 TI - A survey of the training of Canadian health professionals to counsel against smoking. AB - Canadian schools that train health professionals were asked to evaluate the amount of teaching of counselling skills to prevent clients from starting smoking or to help them quit, the topics covered, the knowledge and counselling skill level of their graduates and whether an integrated smoking counselling program was needed for their school. Responses to a questionnaire were received from the Assistant Dean of Undergraduate Studies, the Assistant Dean of Postgraduate Studies and/or the Postgraduate Program Director of 165 professional schools or departments of 283 contacted (58% response rate). For those schools that replied that they taught counselling about smoking, they devoted more hours in the curriculum (range 1-11 hours) to education about the diseases caused by smoking than to counselling children or adults against smoking or helping smokers to quit. Nursing schools tended to have integrated health education curricula, and it was therefore difficult for them to identify the hours devoted exclusively to counselling about tobacco. Few of the deans or program directors of any of the professional schools estimated the knowledge and counselling skills of their graduates as superior, and a majority felt that an integrated smoking counselling curriculum was needed for their school. PMID- 9375260 TI - Combining qualitative and quantitative research methods: considering the possibilities for enhancing the study of chronic diseases. AB - This paper discusses some of the underlying reasons why health researchers have historically had difficulty working collaboratively across qualitative and quantitative research paradigms and argues why it is imperative that researchers move beyond traditional adherence to particular methods of inquiry. Chronic illnesses are prime examples of conditions that by their very nature need to be studied from a combination of perspectives, using both qualitative and quantitative methods. We suggest that the success of health research on managing these conditions lies in the shared application of both qualitative and quantitative research perspectives, methods and tools. In addition, we argue that effective research into long-term chronic illnesses requires not only combined research efforts but also longitudinal programs of study, so that the experience of managing chronic conditions can be captured over time. PMID- 9375261 TI - Glomerular diseases in patients with hepatitis C virus infection after renal transplantation. AB - Currently, it is well known that hepatitis c virus (HCV) represents the major cause of chronic liver disease in renal transplant patients. On the other hand, HCV has been described in association with different types of glomerular diseases, usually type I membranoproliferative glomerulonephritis (MGPN) and less frequently membranous glomerulonephritis (MGN). After renal transplantation two glomerular entities have described in HCV positive patients: MPGN, associated or not with cryoglobulinemia, hypocomplememtemia and rheumatoid factor and another lesion was MGN. All patients had chronic HCV infection and with detectable HCV RNA in the serum, developed proteinuria, nephrotic syndrome and microhematuria. Characteristically MGN occurs without cryoglobulinemia, hypocomplememtemia and rheumatoid factor. The clinical pictures and outcomes of these pathological pictures seem to be similar to those of the novo MPGN or MGN in renal transplant patients. These entities seem to be more frequent in HCV-positive than in HCV negative patients. Also, a possible relationship between HCV infection and transplant glomerulopathy has been described. Therefore, in renal transplant patients with proteinuria, serology for HCV infection, HCV RNA and immunological tests should be performed as part of the differential diagnosis. PMID- 9375262 TI - What's new in the delivery of care in end-stage renal failure? PMID- 9375263 TI - The National Kidney Foundation Dialysis Outcomes Quality Initiative. AB - Rigorously developed clinical practice guidelines have the potential to change practice patterns to obtain improved patient outcomes. Toward that end, in March 1995 the National Kidney Foundation initiated the Dialysis Outcomes Quality Initiative, a comprehensive effort to create literature-based clinical practice guidelines in nephrology. Independent interdisciplinary work groups reviewed the available body of scientific literature on the following topics: hemodialysis adequacy, peritoneal dialysis adequacy, vascular access, and anemia. More than 11,000 papers were identified; of these approximately 1500 were found to be relevant, requiring formal structured review. Work groups formulated draft guidelines with supporting rationales that included the evidentiary basis for the recommendations. The draft guidelines were subjected to an unprecedented three stage review process that involved more than 50 organizations from the renal community, including end-stage renal disease networks, patients dialysis providers, managed care organizations, and government. The finalized guidelines were issued in September 1997. Planned guideline implementation activities will focus on achieving the following: cooperation from the renal community; education of patients, clinicians, policy makers, and dialysis providers; information system tools to facilitate adoption of the guidelines; and evaluation strategies to determine whether practice patterns and outcome goals are achieved. PMID- 9375264 TI - Optimal hematocrit for hemodialysis. AB - Considerable controversy continues over the optimal hematocrit target for dialysis patients being treated with recombinant erythropoietin. Recent short term studies have demonstrated a significant improvement in brain function when hematocrit is 42% compared with when it is 31%. Questions regarding the safety of long-term maintenance of a normal hematocrit have been raised; however, this is in part because of the early termination of the Normal Hematocrit Cardiac Trial, in which there was an increased occurrence of death or nonfatal myocardial infarction in patients randomly assigned to the normal hematocrit group. For the present, a target hematocrit of 36% seems reasonable and safe. PMID- 9375265 TI - Biocompatibility in haemodialysis: fact and fiction. AB - Several of the pro-inflammatory pathways that are activated in patients during dialysis have the potential of producing many side effects. These occur three times a week, accompanying dialysis, and are particularly intense in patients dialysed with so-called 'bioincompatible' membranes. Despite the proven biological superiority of biocompatible membranes, we lack definitive evidence that complement and cell activation three times a week over a period of years is detrimental to patients, because the results of prospective randomized studies are conflicting. Although they do not lead to a decrease in acute clinical symptoms, epidemiological studies suggest that semi-synthetic and synthetic membranes may reduce morbidity and mortality in dialysis patients. Further large scale, prospective and randomized trials with a long follow-up are needed in order to clarify the clinical effects of biocompatibility per se, the increasingly recognized clinical importance of high-flux treatments and the possible interaction between biocompatibility and membrane flux. PMID- 9375266 TI - Delayed graft function: immediate and late impact. AB - Delayed graft function remains a frequent problem after renal transplantation, which is often associated with subsequent graft failure. The major risks for delayed graft function are incurred during organ procurement, preservation, and transplantation, and are predominated by ischemic injury. The cofactors associated with delayed graft function that lead to subsequent poor outcome include early acute rejection as well as immunologic risk factors for rejection, such as presensitization, human leukocyte antigen mismatch, and previous loss of graft. Numerous diagnostic and therapeutic approaches have been assessed in recent years, but predicting or modifying adverse outcomes associated with delayed graft function in a given patient remains unreliable. PMID- 9375267 TI - Renal transplant biopsy: what does it tell? AB - The value of the renal allograft biopsy has been significantly enhanced by several developments in 1997 including the following: the first convincing demonstration that molecular biology techniques can be applied to renal allograft tissue to obtain a diagnosis of acute rejection with high sensitivity and specificity; the development of an improved, internationally agreed classification of kidney transplantation pathology ('Banff 1997'); and significant new insights into the specific pathology of chronic rejection, involving splitting and lamination of peritubular capillary basement membranes and the presence of increased apoptotic cell death. Although it is predictable that long-term technology might eliminate the need for renal allograft biopsies altogether, in the short term these new breakthroughs will greatly increase the value of this procedure in the management of renal transplant patients. PMID- 9375268 TI - The treatment of steroid-induced bone loss in transplantation. AB - Osteopenia after transplantation is a significant cause of morbidity. Despite the lack of randomized, placebo-controlled trials in renal transplantation, there is literature supporting both the prevention and treatment of existing corticosteroid-induced osteoporosis with antiresorptive agents, such as calcitonin and bisphosphonates. The newer pharmacologic agents, nasal spray calcitonin and alendronate, have shown promising results in postmenopausal osteoporosis, and their ease of administration and low incidence of side effects make them ideal for renal transplant patients. PMID- 9375269 TI - Microalbuminuria and essential hypertension: renal and cardiovascular implications. AB - Microalbuminuria continues to receive attention in patients with hypertension, even if they do not have diabetes mellitus. The attention appears deserved, because microalbuminuria has emerged as an important risk factor for left ventricular hypertrophy, myocardial infarction, stroke, peripheral vascular disease and retinopathy, independent of blood pressure. Microalbuminuria may be a useful measurement during pregnancy and appears particularly indicated in following up women who develop pre-eclampsia during pregnancy. In addition to diabetes, increased blood pressure and age, the smoking habit appears to be the most important factor contributing to microalbuminuria, although other influences including uranium exposure have been implicated. We need to learn more about the mechanisms of microalbuminuria, particularly in non-diabetic hypertensive patients. Microalbuminuria is potentially reversible. All antihypertensive agents appear to reduce microalbuminuria. In diabetic patients, angiotensin-converting enzyme inhibitor therapy is effective in reducing renal disease progression, even in the absence of hypertension. Antioxidant therapy may be effective. Stopping smoking should be the initial antioxidant measure. PMID- 9375270 TI - Diagnosis and treatment of ischemic heart disease in dialysis patients. AB - Ischemic heart disease is the major cause of death in dialysis patients. Efforts at coronary artery disease detection in end-stage renal disease patients have primarily focused on the cardiac evaluation of 'high-risk' renal transplant candidates. Despite their high cardiac risk, no data exist on the results of reperfusion therapy in dialysis patients with acute myocardial infarction, and the outcome of coronary revascularization procedures remains controversial. This review highlights recent work on the diagnosis and treatment of coronary artery disease in dialysis patients. PMID- 9375271 TI - Laboratory diagnosis of anaemia in dialysis patients: use of common laboratory tests. AB - Almost all patients with end-stage renal disease suffer from renal anaemia of multifactorial pathogenesis. The use of recombinant human erythropoietin to raise the haematocrit has been a major advance in the care of patients with end-stage renal disease. The majority of these patients develop absolute or functional iron deficiency. However, the diagnosis of iron deficiency is hindered by the inaccuracy of commonly used tests. Serum ferritin and transferrin saturations are frequently used, but limitations with both parameters in end-stage renal disease patients have resulted in the development of new tests to assess iron sufficiency. The percentage of hypochromic red blood cells and particularly reticulocyte haemoglobin content are new measures of iron status in end-stage renal disease patients. An enhanced knowledge of the interpretation of available laboratory parameters will ensure that the patients receive the full benefit from their treatment with recombinant human erythropoietin and iron. PMID- 9375272 TI - Assessment of access recirculation during haemodialysis. AB - With dialysis lines in the correct alignment, access recirculation only occurs when the access blood flow rate is exceeded by the extracorporeal blood flow rate. The degree of access recirculation is accurately measured by non-urea-based methods using indicator dilution or differential conductivity methods. The classical urea-based methods have inherent inaccuracies. Access flow rate can be calculated from an accurate measurement of the access recirculation induced by dialysis line reversal. Access flow rate monitoring can detect early access dysfunction; the existence of access recirculation indicates severe access dysfunction. PMID- 9375273 TI - Renovascular hypertension. AB - In the vast population of patients with established hypertension, there is a small group in whom the blood pressure elevation is caused by renal ischemia. These patients have renovascular hypertension, which can presently be diagnosed with greater precision than in the past. The exact prevalence of renovascular hypertension is not known and the diagnosis is probably missed in many patients. It is important to recognize this condition in clinical practice, because it is a correctable from of secondary hypertension and because it is a reversible cause of renal failure in some patients. Clinical identification of patients with renovascular hypertension has been so imprecise and complex that the very diagnostic quest for this condition has been questioned. However, it is well recognized that renovascular disease is a progressive disorder with serious sequelae if appropriate therapy is not rendered. PMID- 9375274 TI - Dialysis and transplantation. PMID- 9375275 TI - Diagnostics and techniques. PMID- 9375276 TI - Muscle imaging in inflammatory myopathies. AB - Myositides are characterized by perivascular and intrafascicular inflammatory infiltrates and often by fiber de- and regeneration. In chronic disease, muscle size decreases, and replacement of muscle parenchyma by adipose and fibrous tissue (and, in childhood myositis, calcifications of the muscles and subcutaneous fat) occurs. Muscle imaging techniques such as ultrasonography and magnetic resonance (MR) imaging facilitate the assessment of the type (edema, inflammation, fat, fibrosis, and calcifications), degree, and localization of these alterations. Both methods allow evaluation of the activity, chronicity, and severity of myositis and assist in directing the biopsy site. However, MR imaging is more sensitive in the detection of muscle edema, which is common in the early stages of inflammatory myopathies. In general, MR tomographic features provide more information regarding the differential diagnosis than do creatine kinase activity and even electromyography. Muscle imaging techniques should be considered in the diagnostic evaluation and to assist in treatment of inflammatory myopathies. This paper reviews the value and limitations of muscle imaging in inflammatory myopathies. PMID- 9375277 TI - Evaluation and treatment of speech and swallowing disorders associated with myopathies. AB - Dysphagia, or disordered swallowing, can be demonstrated at any time over the course of many myopathies. Ability to swallow may be impaired because of weakness, inflammation, or dysfunction of the oropharyngeal, laryngeal, and esophageal musculature. Dysphagia may occur during the progression of disease regardless of whether the patient is properly treated. The presentation of signs of dysphagia can vary among patients because of differing patterns of weakness or incoordination of the facial muscles, lips, tongue, palate, pharyngeal constrictors, or smooth and striated muscles of the esophagus. Although the literature has focused on problems in the esophagus, scant attention has been paid to the oropharynx, which is often equally affected. Studies suggest that surgical myotomy and botulinum toxin injection may provide benefits for some patients with esophageal dysfunction. Although the condition is pervasive, there is little information on the incidence of dysphagia in muscular disorders. Because a major complication of dysphagia is aspiration, any sign of swallowing impairment demands medical attention and treatment. PMID- 9375278 TI - Diagnosis of the mitochondrial encephalomyopathies. AB - In few fields of medicine has recent progress been as fast and exciting as in the area of mitochondrial diseases. Although the clinical manifestations of mitochondrial dysfunction are extremely variable, biochemical and genetic classification of these disorders is now possible and recent advances in morphologic analysis and genetic testing aid in the identification of patients. What makes these diseases uniquely interesting from a genetic point of view is the fact that mitochondria contain their own DNA, which has distinct genetic properties. It is in the area of mitochondrial DNA defects that there has been extraordinary progress in the past few years, and a new chapter of human genetics, "mitochondrial genetics," has opened up and is becoming increasingly important in the differential diagnosis and in genetic counseling. PMID- 9375279 TI - Idiopathic orbital myositis. AB - Idiopathic orbital myositis is a subtype of nonspecific orbital inflammation primarily involving the extraocular muscles. It occurs most frequently in young to middle-aged adults with a 2 to 1 female predominance. The cardinal clinical feature is orbital pain exacerbated by eye movement. Other common findings include diplopia, proptosis (which is generally minimal), conjunctival injection and chemosis, and periorbital edema. Thyroid eye disease is commonly confused with orbital myositis, but the latter is characterized by a more acute onset, more severe pain, and a rapid response to systemic corticosteroid therapy. Echography and CT scanning reveal enlarged muscle bellies and thickened tendons, with low internal reflectivity echographically. Although the cause of orbital myositis is unknown, an immune-mediated pathophysiologic mechanism is likely. This review summarizes recent findings regarding the epidemiology, diagnosis, pathophysiology, and treatment of idiopathic orbital myositis. PMID- 9375280 TI - Myositis associated with graft-versus-host disease. AB - A polymyositis syndrome has been described as a rare complication in patients who develop chronic graft-versus-host disease after allogeneic bone marrow transplantation. Chronic graft-versus-host disease is a cellular immune-mediated donor bone marrow versus patient rejection reaction, which may also lead to an autoimmune pathologic process. Chronic graft-versus-host disease-related polymyositis appears to be very similar to idiopathic myositis in its clinicopathologic presentation; chronic graft-versus-host disease-related myositis responds well to prednisone but cyclosporine may be an important component of second-line therapy due to its efficacy in controlling underlying chronic graft-versus-host disease. PMID- 9375281 TI - Cellular immune mechanisms in inflammatory myopathies. AB - The inflammatory myopathies include dermatomyositis, polymyositis, and inclusion body myositis. In dermatomyositis, muscle fiber injury is secondary to an antibody- or immune-complex-mediated immune response against a vascular endothelial component. In polymyositis and inclusion body myositis, CD8+ T cells and macrophages invade and eventually destroy initially nonnecrotic muscle fibers. The autoaggressive T cells have the phenotype of activated (HLA-DR+) memory (CD45RO+) cells. T-cell receptor analyses indicate that the autoaggressive T cells are oligoclonal. In inflammatory lesions, muscle fibers express various cytoplasmic and surface molecules that are not detectable in normal fibers. These molecules, which include HLA class I antigens, heat-shock proteins, adhesion molecules, and Fas, are probably induced by locally secreted cytokines. The autoaggressive CD8+ T cells harbor granules containing perforin that aggregate near the contact zone with the target muscle fiber. This is consistent with a perforin- and secretion-dependent mechanism of muscle fiber injury. Many invaded muscle fibers also express the Fas "death receptor," but signs of apoptosis are absent. PMID- 9375282 TI - Classification criteria for the idiopathic inflammatory myopathies. AB - Inasmuch as the clinical features of the idiopathic inflammatory myopathies are not easily differentiated from those of other similar rheumatic and neurologic conditions, diagnosis is often difficult. Various classification criteria for polymyositis and dermatomyositis have been suggested by a number of investigators. The most commonly accepted and used criteria include symmetric proximal muscle weakness, serum elevations of muscle enzymes, the classic electromyographic and muscle biopsy findings of inflammatory myopathy, and the typical skin rash of dermatomyositis. Although these criteria are clinically useful, they can result in misdiagnoses and inappropriate therapies. They also result in heterogeneous patient groups being selected for clinical and laboratory studies. Furthermore, they do not include recent findings related to the myositis specific autoantibodies and magnetic resonance imaging of muscle that have been found to be important adjuncts in assessing patients with muscle weakness or elevations of muscle enzymes. A modification to the Bohan and Peter criteria is proposed to include myositis-specific autoantibodies and magnetic resonance imaging. This proposal could initiate productive discussions and investigations of the sensitivity and specificity of new classification criteria for myositis and could ultimately enhance our treatment capabilities. PMID- 9375283 TI - Role of metal-catalyzed oxidation reactions in the early pathogenesis of scleroderma. AB - The observation that revelation of immunocryptic epitopes in self-antigens may initiate the autoimmune response has prompted the search for processes that induce novel autoantigen structure as potential initiators of autoimmunity. Recent studies have demonstrated that the autoantigens targeted in diffuse scleroderma are unified by their enrichment in nucleolini and by their susceptibility to fragmentation in a novel metal-dependent reaction that requires the generation of reactive oxygen species. Several other studies highlight the importance of reactive oxygen species as mediators of damage during ischemia reperfusion and present evidence for increased generation of these radicals in patients with scleroderma. Together, these studies suggest a model for the pathogenesis of scleroderma in which metals and free radicals play a central, autoamplifying role. PMID- 9375284 TI - New approaches to Raynaud's phenomenon [corrected]. AB - Dysfunction of vascular tone control is mainly caused by the derangement of endothelium and of the peripheral nervous system. Studies have suggested changes in the nervous system at either the peripheral level (loss of sensory motor nerves, increased alpha 2-receptor activity, and so on) or the central level (impaired thermoregulation), always linked to the profound abnormality of endothelial function. This dual involvement consistently affects the blood flow, which can be measured with several tools (laser Doppler velocimetry, digital blood pressure response, and so on). Studies have analyzed serologic and instrumental predictors of a possible development of a connective tissue disease in Raynaud's phenomenon. A new wave of studies addressed the role of reperfusion injury and oxygen radicals in provoking chromosomal breakage and generating an immune response through fragmentation of autoantigens in the presence of metals. Antioxidants have been proposed as efficacious treatment of Raynaud's phenomenon. The continued study of regeneration of vessels (therapeutic angiogenesis) may open a new avenue for the treatment of Raynaud's phenomenon and the loss of angiogenesis as in diffuse scleroderma. PMID- 9375285 TI - Epidemiology of systemic sclerosis and related diseases. AB - Epidemiologic studies of scleroderma can provide insight into the dynamics of disease expression over time, over different geographic areas, and over diverse ethnic populations. Although such population studies cannot establish cause and effect relationships, they can reveal associations previously obscured by the relative rarity and clinical diversity of this disease. The incidence rate of systemic sclerosis has been stable over the past 20 years at 19 new cases per million per year. The incidence rate of localized scleroderma or morphea is reported at 27 new cases per million per year and has a benign prognosis overall. Disease expression of systemic scleroderma is influenced by genetic, ethnic, and environmental factors. A cluster of scleroderma cases among Choctaw Native Americans in Oklahoma provides an opportunity to investigate the interaction of genetic and environmental influences. Twin studies suggest a definite but relatively weak genetic component. Case-control studies regarding environmental and occupational exposures have yet to identify risk factors that could serve as triggers for this disease. PMID- 9375286 TI - Eosinophilia-myalgia syndrome, eosinophilic fasciitis, and related fibrosing disorders. AB - Clinically distinct fibrosing processes affecting the skin, selected internal organs, or both in a characteristic pattern are a common cause of morbidity. In addition to systemic sclerosis, the prototype idiopathic fibrosing disorder, these conditions include the eosinophilia-myalgia syndrome, epidemic toxic oil syndrome, eosinophilic fasciitis, localized forms of scleroderma, keloid, and the newly described entity of fibrosing colonopathy. The pathogenesis of these disorders, although still incompletely understood, appears to share similarities with that of systemic sclerosis. Insights into these diseases have recently emerged from epidemiologic and toxicoepidemiologic investigations, in situ hybridization and polymerase chain reaction amplification of target genomes, and in vivo and in vitro experimental research. Minor contaminants in food supplements, activation and degranulation of eosinophils, altered expression of CD34 antigen on dendritic cells, disordered regulation of fibroblast apoptosis and proliferation, infection with Borrelia organisms, and cytokines such as transforming growth factor-beta, interleukin-4, and connective tissue growth factor are implicated in inducing an accentuated and persistent fibrogenic host response to injury, resulting in tissue fibrosis. In addition, humoral and cellular autoimmunity may also be implicated. PMID- 9375287 TI - Skin involvement as a relevant outcome measure in clinical trials of systemic sclerosis. AB - Advances in our understanding of the pathobiology of scleroderma and the ever increasing availability of rational candidate therapies have brought the clinical study of scleroderma to the forefront. In the 1990s, consensus measures of outcome have been developed for common disorders such as rheumatoid arthritis. With decisions founded on extensive and validated data, the clinical research community and regulatory agencies have accepted the importance of a demonstration of small degrees of change over relatively short periods of time. The current level of sophistication in scleroderma research is reminiscent of our approach to the study of rheumatoid arthritis in the early 1970s. Accessible, reproducible, and cost-effective measures of outcome are needed in scleroderma. These measures should incorporate clinical meaningfulness and be relevant to quality of life. This review discusses some of the more recent studies of outcome measures in scleroderma, some or all of which are considered relevant to both drug development and clinical care of the individual patients. PMID- 9375288 TI - Myositis and myopathies. PMID- 9375289 TI - Raynaud's phenomenon, scleroderma, overlap syndromes, and other fibrosing syndromes. PMID- 9375290 TI - Detection of erythromycin resistant methylase gene by the polymerase chain reaction. AB - A polymerase chain reaction (PCR) protocol was developed that could specifically amplify a 520-bp region of the erythromycin resistant methylase (ermC) gene sequence. The identity of the PCR-amplified 520-bp DNA was confirmed by HinCII endonuclease restriction digestion, which produced the predicted 440-bp and 80-bp DNA fragments. A 20-mer (alpha-32P) oligonucleotide probe specifically hybridized with these amplified products confirming the specificity and reliability of this diagnostic assay. The assay could detect the ermC gene in bacterial suspensions containing as few as 10(3) cells ml-1. The assay was used to detect the presence of the ermC gene in several Gram-positive bacterial strains identified as Streptococcus sp., Staphylococcus sp., Micrococcus sp., Lactobacillus sp. and Enterococcus sp., isolated from water samples maintained in experimental animal cages and clinical sources. Only bacteria identified as Staphylococcus sp. were resistant to the antibiotic. Although 17 strains of Staphylococcus sp. isolated from clinical samples were resistant to erythromycin, only seven of these isolates tested positive for the presence of the ermC gene. Of these strains, five were identified as coagulase-positive S. aureus and the rest were identified as coagulase-negative S. epidermidis. The erythromycin resistance in all seven ermC positive isolates was constitutive. The entire diagnostic assay, including template preparation, amplification and electrophoresis can be completed within 6 h. PMID- 9375291 TI - DNA-probes for the differentiation of Capnocytophaga species. AB - We designed oligonucleotides to differentiate between the seven currently known Capnocytophaga species. The oligonucleotides were labelled non-radioactively at the 3' end with digoxigenin. The specificity could be demonstrated in a dot-blot hybridization assay by using the type strains, reference strains, and 37 clinical Capnocytophaga isolates as well as 11 representative strains of other taxa as a template. The sensitivity of the assay was calculated with 10(3) bacteria per dot. PMID- 9375292 TI - Construction and use of PCR primers from a 70 kDa heat shock protein gene for identification of Candida albicans. AB - Methods for detection of Candida albicans in culture or biological samples were developed by the use of polymerase chain reaction (PCR) with oligonucleotide primers from C. albicans 70 kDa heat shock protein gene (Cahsp70). The PCR amplifies a 335-base pair fragment which is then hybridized with a non radioactive probe, leading to the specific identification of C. albicans and its differentiation from all other human pathogenic Candida and/or yeast species. Candida albicans could be rapidly detected in human urine and blood, with a sensitivity of 10 and 50 fungal cells per sample, respectively. PMID- 9375293 TI - A rapid and sensitive method for non-isotopic quantitation of HIV-1 RNA using thermophilic SDA and flow cytometry. AB - Thermophilic strand displacement amplification (tSDA) is an isothermal DNA amplification technique that proceeds at 55-60 degrees C using both a thermostable restriction enzyme and a DNA polymerase. A modification of this system has been developed that allows the simultaneous amplification and detection of a DNA target by the addition of a detector probe to the reaction. This tSDA system has been further modified into a flow cytometry-based, bead capture assay for quantitation of HIV-1 RNA. A biotinylated capture probe and digoxygenin-dUTP have been incorporated into the tSDA reaction. The resulting double labelled amplicons are captured on strepavidin beads, and a fluorescent signal is generated on the beads by staining with fluorescent anti-digoxygenin antibody. The assay has a linear dynamic range of three orders of magnitude with a lower detection limit at 250 HIV-1 RNA molecules. PMID- 9375294 TI - Strain differentiation of isolates of streptococci from bovine mastitis by pulsed field gel electrophoresis. AB - Pulsed-field gel electrophoresis (PFGE) was examined as a tool to differentiate strains of streptococci isolated from clinical and sub-clinical cases of bovine mastitis. Analysis of SmaI chromosomal digests of Streptococcus agalactiae, S. dysgalactiae subsp. dysgalactiae and S. uberis isolates revealed intraherd and interherd strain relationships within each species. Comparison of S. agalactiae isolates from the same herd revealed little variability in their SmaI restriction patterns indicating a single strain originating from a common source of infection. However, comparison of S. agalactiae isolates between herds showed that each herd was infected with a distinct strain. The restriction profiles from S. dysgalactiae subsp. dysgalactiae and S. uberis were more diverse and often multiple strains of both species were present within an individual herd, with some herds containing more than one representative of a particular strain. Interestingly, it was only observed with S. dysgalactiae subsp. dysgalactiae that some strains were present in more than one herd. PFGE was found to be a useful and reproducible method for the discrimination of different strains of the three most important species of streptococci responsible for bovine mastitis and to offer a means to identify environmental sources of infection. PMID- 9375295 TI - Restriction endonucleases whose sites are predictable from the amino acid sequence offer an improved strategy for typing bovine rotaviruses. AB - Variation in the third base of a codon hampers genotypic characterization, particularly of RNA viruses. Some restriction endonucleases, however, have a recognition site with a variable base at the third position and will always cleave when a certain amino acid pair occurs (such as glycine-proline for Sau96I and glutamic or aspartic acid followed by serine usually for HinfI). We developed a restriction fragment length polymorphism (RFLP) procedure based on these enzymes for P-typing bovine group A rotaviruses (BRV). Employing this procedure 20 BRV local strains, isolated in tissue culture as well as the original faecal sample, could be typed in one of three patterns. More variability was observed when restriction endonucleases were employed whose cleavage sites cannot be predicted from the amino acid sequence (TaqI and Tsp509I). These RFLP results agreed with the PCR-VP4 typing assay, neutralization tests, and nucleotide sequence analysis. RFLP with Sau96I and HinfI provided quick and objective P typing of strains and could detect multiple genotypes in the same sample. PMID- 9375296 TI - Specific detection of Serpulina hyodysenteriae and potentially pathogenic weakly beta-haemolytic porcine intestinal spirochetes by polymerase chain reaction targeting 23S rDNA. AB - A 2470-bp section of the 23S ribosomal DNA from Serpulina hyodysenteriae and five biochemically different groups of weakly beta-haemolytic porcine intestinal Serpulina strains was sequenced. The similarity between the sequenced strains was high (96.85% to 99.84%). A phylogenetic tree was estimated by the maximum likelihood method. The sequenced strains formed three groups. Serpulina hyodysenteriae and biochemical group II ('S. intermedius') formed a cluster, but 20 nucleotide positions were different between the two, suggesting that biochemical group II is a separate species. Another cluster consisted of the closely related biochemical group IIIa ('S. murdochii') and IIIb/c (S. innocens) (99.84% similarity), while biochemical group IV (S. pilosicoli) constituted a separate group with a relatively low similarity (96.85% to 97.01%) to the other groups. Three primer pairs were designed for specific PCR detection of the clinically important S. hyodysenteriae and biochemical group II and IV. PCR amplification was accomplished with DNA extracted from bacterial colonies by a simple boiling procedure, and with DNA extracted directly from porcine stool samples using a bead beating extraction procedure. The level of detection for the direct extraction and amplification method was 5 x 10(5) cells added g-1 normal faeces. PMID- 9375297 TI - Use of four DNA insertion sequences to characterize strains of the Mycobacterium avium complex isolated from animals. AB - The Mycobacterium avium complex (MAC) includes the closely related species M. avium, M. intracellulare and M. paratuberculosis. The insertion elements IS900, IS901, IS1245 and IS1311 were used as DNA probes to characterize by restriction fragment polymorphisms (RFLPs) eight reference strains, three animal isolates of M. paratuberculosis from outside New Zealand and 61 selected New Zealand MAC isolates from cattle, deer, pigs, sheep and humans. IS900 was found only in strains of M. paratuberculosis. All MAC strains contained IS1311 and the RFLPs associated with this insertion element divided M. paratuberculosis strains into the same groups as IS900 RFLPs. Except for M. paratuberculosis, all MAC strains contained IS1245 and the majority of those from lesions in cattle, deer and pigs also contained IS901. All animal strains containing IS901 had the same RFLPs with IS901, IS1245 and IS1311. In three cases, these apparently identical strains could be differentiated by restriction fragment analysis with BstEII. IS901 was not present in four human isolates or in isolates from deer without lesions. These results indicate that a very closely related group of strains causes the majority of non-paratuberculosis MAC lesions in animals in New Zealand. PMID- 9375298 TI - A common polymorphism in exon 16 of the human insulin-like growth factor-1 receptor gene (IGF1R). PMID- 9375299 TI - Head-to-tail primer tandem repeats generated in hemi-nested PCR. AB - Evidence that hemi-nested PCR protocols are prone to the development of artifacts consisting of multiple head-to-tail primer tandem repeats is presented. This phenomenon was more pronounced with the addition of a large amount of template into the second round PCR and was limited to the primer used in both first and second reactions. PMID- 9375300 TI - Heat shock proteins and heat adaptation of the whole organism. AB - Adaptation to heat may occur through acclimatization or thermotolerance; however, the linkage of these phenomena is poorly understood. The importance of heat shock proteins (HSPs) in thermotolerance and differences in their accumulation in organisms adapted to the heat suggest a role for HSPs in acclimatization as well. The role of HSPs in heat adaptation of the whole organism and the interrelationships among heat adaptation, endotoxin tolerance, and cytokine resistance through HSPs are reviewed. PMID- 9375301 TI - Dynamic properties of lung parenchyma: mechanical contributions of fiber network and interstitial cells. AB - We investigated the contributions of the connective tissue fiber network and interstitial cells to parenchymal mechanics in a surfactant-free system. In eight strips of uniform dimension from guinea pig lung, we assessed the storage (G') and loss (G") moduli by using pseudo-random length oscillations containing a specially designed set of seven frequencies from 0.07 to 2.4 Hz at baseline, during methacholine (MCh) challenge, and after death of the interstitial cells. Measurements were made at mean forces of 0.5 and 1 g and strain amplitudes of 5, 10, and 15% and were repeated 12 h later in the same, but nonviable samples. The results were interpreted using a linear viscoelastic model incorporating both tissue damping (G) and stiffness (H). The G' and G" increased linearly with the logarithm of frequency, and both G and H showed negative strain amplitude and positive mean force dependence. After MCh challenge, the G' and G" spectra were elevated uniformly, and G and H increased by < 15%. Tissue stiffness, strain amplitude, and mean force dependence were virtually identical in the viable and nonviable samples. The G and hence energy dissipation were approximately 10% smaller in the nonviable samples due to absence of actin-myosin cross-bridge cycling. We conclude that the connective tissue network may also dominate parenchymal mechanics in the intact lung, which can be influenced by the tone or contraction of interstitial cells. PMID- 9375302 TI - Nitric oxide derived from sympathetic nerves regulates airway responsiveness to histamine in guinea pigs. AB - Nitric oxide (NO), which can be derived from the nervous system or the epithelium of the airway, may modulate airway responsiveness. We investigated how NO derived from the airway nervous system would affect the airway responsiveness to histamine and acetylcholine in mechanically ventilated guinea pigs. An NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) (1 mmol/kg i.p.) significantly enhanced airway responsiveness to histamine but not to acetylcholine. Its enantiomer D-NAME (1 mmol/kg i.p.), in contrast, had no effect. The L-NAME-induced airway hyperresponsiveness was still observed in animals pretreated with propranolol (1 mg/kg i.v.) and atropine (1 mg/kg i.v.). Pretreatment with the ganglionic blocker hexamethonium (2 mg/kg i.v.) completely abolished enhancing effect of L-NAME on airway responsiveness. Bilateral cervical vagotomy did not alter the L-NAME-induced airway hyperresponsiveness, whereas sympathetic stellatectomy completely abolished it. Results suggest that NO that was presumably derived from the sympathetic nervous system regulates airway responsiveness to histamine in guinea pigs. PMID- 9375303 TI - Cerebral areas associated with motor control of speech in humans. AB - We have defined areas in the brain activated during speaking, utilizing positron emission tomography. Six normal subjects continuously repeated the phrase "Buy Bobby a poppy" (requiring minimal language processing) in four ways: A) spoken aloud, B) mouthed silently, C) without articulation, and D) thought silently. Statistical comparison of images from conditions A with C and B with D highlighted areas associated with articulation alone, because control of breathing for speech was controlled for; we found bilateral activations in sensorimotor cortex and cerebellum with right-sided activation in the thalamus/caudate nucleus. Contrasting images from conditions A with B and C with D highlighted areas associated with the control of breathing for speech, vocalization, and hearing, because articulation was controlled for; we found bilateral activations in sensorimotor and motor cortex, close to but distinct from the activations in the preceding contrast, together with activations in thalamus, cerebellum, and supplementary motor area. In neither subtraction was there activation in Broca's area. These results emphasize the bilaterality of the cerebral control of "speaking" without language processing. PMID- 9375304 TI - Central neural correlates of learned heart rate control during exercise: central command demystified. AB - To identify the brain areas involved in central command, four monkeys were trained to attenuate the tachycardia of exercise while different brain sites affecting heart rate (HR) were simultaneously stimulated electrically. Among 24 brain sites located mostly in the limbic structures, we have identified four types of control systems that mediate cardiovascular and motor behavior during exercise. One system increases HR equivalently during both exercise and operantly controlled HR, whereas another increases HR during both tasks and abolishes operant HR control. In the third system, the effect of brain stimulation on HR is attenuated during exercise and during exercise with operantly controlled HR. The fourth system increases HR in both tasks, but its effect is significantly attenuated during operant HR control. We believe that this last system, which includes the mediodorsal nucleus, nucleus ventralis anterior, and cingulate cortex, plays a significant role in central command. PMID- 9375305 TI - Cardiovascular responses during spontaneous overground locomotion in freely moving decerebrate cats. AB - To examine whether the cerebrum is essential for producing the rapid cardiovascular adjustment at the beginning of overground locomotion, we examined heart rate (HR), mean arterial blood pressure (MAP), and integrated electromyogram (iEMG) of the forelimb triceps brachialis muscle in freely moving decerebrate cats during locomotion. Two to four days after decerebration surgery performed at the level of the precollicular-premammillary body, the animals spontaneously produced coordinated overground locomotion, supporting body weight. HR began to increase immediately before the onset of iEMG, and MAP began to rise almost simultaneously with the iEMG onset. Their increases in HR and MAP (24 +/- 3 beats/min and 22 +/- 4 mmHg) were sustained during locomotion. Sinoaortic denervation (SAD) did not affect the abrupt changes in HR and MAP at the beginning of locomotion (0-4 s from the onset of iEMG), whereas SAD had a contrasting effect during the subsequent period, a decrease in the HR response (9 +/- 1 beats/min) and an increase in the MAP response (30 +/- 3 mmHg). These results suggest that the cerebrum and the rostral part of the diencephalon are not essential for producing the rapid cardiovascular adjustment at the beginning of spontaneous overground locomotion. The arterial baroreflex does not contribute to this rapid adjustment but plays an important role in regulating the cardiovascular responses during the later period of spontaneous locomotion. PMID- 9375306 TI - Exercise, alveolar macrophage function, and susceptibility to respiratory infection. AB - The effects of exercise on susceptibility to respiratory infection were determined by using a murine model of intranasal challenge with herpes simplex type 1 virus (HSV-1). Two doses of treadmill exercise were assessed: moderate short-term (30 min) exercise and prolonged strenuous exercise to voluntary fatigue (2.5-3.5 h). Morbidity and mortality among exercised and control mice were compared after intranasal challenge with HSV-1. We also assessed the ability of alveolar macrophages to restrict HSV-1 viral replication (intrinsic resistance) among exercise and control groups of mice at several time points postexercise. Exercise to fatigue followed by exposure to viral infection resulted in greater morbidity and mortality than either no exercise or short-term moderate exercise. In addition, antiviral resistance of macrophages obtained from the lungs of both exercised groups was suppressed, albeit for a longer duration in the fatigued group. These data are particularly important in that they identify an exercise-induced decrease in antiviral resistance of a specific component of the immune system within the lungs, in conjunction with increased susceptibility to respiratory infection in vivo. The specific mechanism of decreased antiviral resistance of alveolar macrophages and its role in respiratory infection after exercise remains to be determined. PMID- 9375307 TI - rG-CSF reduces endotoxemia and improves survival during E. coli pneumonia. AB - We investigated the effects of recombinant granulocyte colony-stimulating factor (rG-CSF) during canine bacterial pneumonia. Beagles with chronic tracheostomies received daily subcutaneous rG-CSF (5 micrograms/kg body wt) or placebo for 14 days, beginning 9 days before intrabronchial inoculation with E. coli. Animals received antibiotics and fluid support; a subset received humidified oxygen (fractional inspired O2 0.40). Compared with controls, rG-CSF increased circulating neutrophil counts (57.4 vs. 11.0 x 10(3)/mm3, day 1 after infection; P = 0.0001), decreased plasma endotoxin (7.5 vs. 1.1 EU/ml at 8 h; P < 0.01) and serum tumor necrosis factor-alpha (3,402 vs. 729 pg/ml at 2 h; P = 0.01) levels, and prolonged survival (relative risk of death = 0.45, 95% confidence interval 0.21-0.97; P = 0.038). Also, rG-CSF attenuated sepsis-associated myocardial dysfunction (P < 0.001). rG-CSF had no effect on pulmonary function or on blood and lung bacteria counts (all P = not significant). Other animals challenged with endotoxin (4 mg/kg i.v.) after similar treatment with rG-CSF had lower serum endotoxin levels (7.62 vs. 5.81 log EU/ml at 6 h; P < 0.01) and less cardiovascular dysfunction (P < 0.05 to < 0.002) but similar tumor necrosis factor-alpha levels (P = not significant) compared with controls. Thus prophylactic rG-CSF sufficient to increase circulating neutrophils during bacterial pneumonia may improve cardiovascular function and survival by mechanisms that in part enhance the clearance of bacterial toxins but do not improve lung function. PMID- 9375308 TI - Differential relaxant responses of pulmonary arteries and veins in lung explants of guinea pigs. AB - The endothelium regulates vascular tone through release of relaxing or contracting factors, with nitric oxide (NO) being a major endothelium-derived relaxing factor. In the present study, we used a lung explant technique to determine the differential abilities and mechanisms of pulmonary arteries and veins of normal guinea pigs to relax after precontraction. Excised lungs of 15 guinea pigs were filled through the airways with 1% agarose, cut into 1-mm-thick slices, and cultured overnight. Luminal areas of vascular cross sections were measured with an image-analysis system. Vessels were precontracted with U-46619, and responses to histamine, acetylcholine (ACh), sodium nitroprusside, and papaverine were examined. We also determined the effects of N omega-nitro-L arginine and of indomethacin on ACh-induced responses. We found that histamine relaxed arteries more than veins and that ACh relaxed only arteries. N omega nitro-L-arginine pretreatment abolished ACh-induced relaxation of arteries and caused ACh-induced contraction of veins, whereas indomethacin markedly augmented ACh-induced relaxation of arteries (maximal relaxation: 48.5 +/- 4.7 vs. 19.2 +/- 5.1% without it) and induced a dose-dependent relaxation of veins (maximal relaxation: 17.0 +/- 4.1%). Sodium nitroprusside induced a significantly greater relaxation of arteries than veins, whereas papaverine relaxed them equally. We conclude that in guinea pigs endothelial NO-mediated relaxation is greater in pulmonary arteries than in veins and that ACh-induced NO-mediated relaxation is reduced by the simultaneous production of cyclooxygenase-derived vasoconstrictors. PMID- 9375309 TI - Impaired muscle glycogen resynthesis after a marathon is not caused by decreased muscle GLUT-4 content. AB - Our purpose was to investigate whether the slow rate of muscle glycogen resynthesis after a competitive marathon is associated with a decrease in the total muscle content of the muscle glucose transporter (GLUT-4). Seven well trained marathon runners participated in the study, and muscle biopsies were obtained from the lateral head of the gastrocnemius muscle before, immediately after, and 1, 2, and 7 days after the marathon, as were venous blood samples. Muscle GLUT-4 content was unaltered over the experimental period. Muscle glycogen concentration was 758 +/- 53 mmol/kg dry weight before the marathon and decreased to 148 +/- 39 mmol/kg dry weight immediately afterward. Despite a carbohydrate rich diet (containing at least 7 g carbohydrate.kg body mass-1.day-1), the muscle glycogen concentration remained 30% lower than before-race values 2 days after the race, whereas it had returned to before-race levels 7 days after the race. We conclude that the total GLUT-4 protein content is unaltered in the lateral gastrocnemius after a competitive marathon and that the slow recovery of muscle glycogen after the race apparently involves factors other than changes in the total content of this protein. PMID- 9375310 TI - Theory of diaphragm structure and shape. AB - The muscle bundles of the diaphragm form a curved sheet that extends from the chest wall to the central tendon. Each muscle bundle exerts a force in the direction of its curvature; the magnitude of this force is proportional to the curvature of the bundle. The contribution of this force to transdiaphragmatic pressure is maximal if the direction of bundle curvature is orthogonal to the surface and the curvature is maximal. That is, the contribution of muscle tension to transdiaphragmatic pressure is maximal if the muscle bundles lie along lines that are both geodesics and lines of maximal principal curvature of the surface. A theory of diaphragm shape is developed from the assumption that all muscle bundles have these optimal properties. The class of surfaces that are formed of line elements that are both geodescis and lines of principal curvature is described. This class is restricted. The lines that form the surface must lie in planes, and all lines must have the same shape. In addition, the orientation of the lines is restricted. An example of this class that is similar to the shape of the canine diaphragm is described, and the stress distribution in this example is analyzed. PMID- 9375311 TI - Adrenergic beta 1- and beta 1 + 2-receptor blockade suppress the natural killer cell response to head-up tilt in humans. AB - To evaluate stress-induced changes in blood leukocytes with emphasis on the natural killer (NK) cells, eight male volunteers were followed during three trials of head-up tilt with adrenergic beta 1- (metoprolol) and beta 1 + 2- (propranolol) blockade and with saline (control) infusions. The beta 1- and beta 1 + 2-receptor blockade did not affect the appearance of presyncopal symptoms, but the head-up tilt induced a transient lymphocytosis that was abolished by beta 1 + 2-receptor blockade but not by beta 1-receptor blockade. Head-up tilt also resulted in delayed neutrophilia, which was insensitive to beta-receptor blockade. Lymphocyte subset analysis revealed that the head-up tilt resulted in a twofold increase in the percentage and absolute number of CD3-/CD16+ and CD3 /CD56+ NK cells in peripheral blood and that this increase was partially blocked by metoprolol and abolished by propranolol. The NK cell activity on a per NK cell basis did not change during head-up tilt, indicating that the cytotoxic capability of NK cells recruited to circulation is unchanged. The data suggest that the head-up tilt-induced lymphocytosis was due mainly to CD16+ and CD56+ NK cells and that their recruitment to the blood was inhibited by beta 1- and especially beta 1 + 2-receptor blockade. Thus stress-induced recruitment of lymphocytes, and of NK cells in particular, is mediated by epinephrine through activation of beta-receptors on the lymphocytes. PMID- 9375312 TI - Effect of particles on sheep lung hemodynamics parallels depletion and recovery of intravascular macrophages. AB - We previously showed in newborn lambs that the pulmonary hemodynamic responses to foreign particulate matter (liposomes; Monastral blue) developed in parallel with the maturation of the pulmonary intravascular macrophage system. We now report our use of the liposome-encapsulated heavy-metal-chelating agent dichloromethylene diphosphonate to deplete the intravascular macrophages of small lambs. Functionally and by quantitative histology, we depleted the vast majority of the intravascular macrophages (71% by Monastral blue particle retention, n = 22; 77% by histology; n = 2). Depletion success increased to > 90% as we optimized the liposome-depletion regime. Recovery of the lung hemodynamic response began within 3 days. By 2 wk, the functional responses had fully recovered (n = 8), and, according to quantitative histology, the macrophage population (n = 2) had recovered 65%. Macrophage depletion in lambs is relatively inexpensive and easy to achieve. It is a safe procedure and is followed by full recovery in approximately 2 wk, provided that an aseptic technique is used to prevent bacteremia. PMID- 9375313 TI - Role of circulating blood components and thromboxane in anaphylactic vasoconstriction in isolated canine lungs. AB - We determined the roles of circulating blood components and chemical mediators in anaphylactic vasoconstriction and microvascular permeability during Ascaris suum antigen-induced anaphylaxis in isolated canine lungs. Either the right or left lower lobe served as the control lung, which was perfused with autologous blood, and the contralateral lobe from the same dog was examined for the effect of albumin Krebs-Henseleit solution (Krebs) or of blockers of various vasoconstrictors with blood perfusion. Pulmonary vasoconstriction occurred after injection of the antigen (15 mg) in both the blood- and Krebs-perfused lungs. However, the percent change of peak pulmonary vascular resistance in the Krebs perfused lungs tended to be greater than that in the blood-perfused lungs (689.9 +/- 289.3 and 389.3 +/- 171.9%, respectively). This increased peak pulmonary vascular resistance was attenuated similarly by pretreatment with indomethacin (1.1 x 10(-4) M; cyclooxygenase inhibitor), AA-2414 (10(-5) M; thromboxane receptor antagonist), or a combination of TCV-309 (10(-5) M; platelet-activating factor-receptor antagonist), diphenhydramine (1.7 x 10(-4) M, histamine H1 receptor antagonist), and indomethacin but not by pretreatment with TCV-309 or diphenhydramine alone. The filtration coefficient, an index of vascular permeability, did not change significantly at 15 or 60 min after the antigen in all groups. These findings suggest that anaphylactic vasoconstriction in the isolated canine lung is independent of circulating blood components. Thromboxane is the major mediator for the anaphylactic vasoconstriction. Anaphylaxis does not increase pulmonary vascular permeability in isolated canine lungs. PMID- 9375314 TI - Gas compression in lungs decreases peak expiratory flow depending on resistance of peak flowmeter. AB - It has recently been shown (O. F. Pedersen T. R. Rasmussen, O. Omland, T. Sigsgaard, P. H. Quanjer. and M. R. Miller. Eur. Respir. J. 9: 828-833, 1996) that the added resistance of a mini-Wright peak flowmeter decreases peak expiratory flow (PEF) by approximately 8% compared with PEF measured by a pneumotachograph. To explore the reason for this, 10 healthy men (mean age 43 yr, range 33-58 yr) were examined in a body plethysmograph with facilities to measure mouth flow vs. expired volume as well as the change in thoracic gas volume (Vb) and alveolar pressure (PA). The subjects performed forced vital capacity maneuvers through orifices of different sizes and also a mini-Wright peak flowmeter. PEF with the meter and other added resistances were achieved when flow reached the perimeter of the flow-Vb curves. The mini-Wright PEF meter decreased PEF from 11.4 +/- 1.5 to 10.3 +/- 1.4 (SD) l/s (P < 0.001), PA increased from 6.7 +/- 1.9 to 9.3 +/- 2.7 kPa (P < 0.001), an increase equal to the pressure drop across the meter, and caused Vb at PEF to decrease by 0.24 +/- 0.09 liter (P < 0.001). We conclude that PEF obtained with an added resistance like a mini-Wright PEF meter is a wave-speed-determined maximal flow, but the added resistance causes gas compression because of increased PA at PEF. Therefore, Vb at PEF and, accordingly, PEF decrease. PMID- 9375316 TI - Chest wall motion during tidal breathing. AB - We have used an automatic motion analyzer, the ELITE system, to study changes in chest wall configuration during resting breathing in five normal, seated subjects. Two television cameras were used to record the x-y-z displacements of 36 markers positioned circumferentially at the level of the third (S1) and fifth (S2) costal cartilage, corresponding to the lung-apposed rib cage; midway between the xyphoid process and the costal margin (S3), corresponding to the abdomen apposed rib cage; and at the level of the umbilicus (S4). Recordings of different subsets of markers were made by submitting the subject to five successive rotations of 45-90 degrees. Each recording lasted 30 s, and three-dimensional displacements of markers were analyzed with the Matlab software. At spontaneous end expiration, sections S1-3 were elliptical but S4 was more circular. Tidal changes in chest wall dimensions were consistent among subjects. For S1-2, changes during inspiration occurred primarily in the cranial and ventral directions and averaged 3-5 mm; displacements in the lateral direction were smaller (1-2 mm). On the other hand, changes at the level of S4 occurred almost exclusively in the ventral direction. In addition, both compartments showed a ventral displacement of their dorsal aspect that was not accounted for by flexion of the spine. We conclude that, in normal subjects breathing at rest in the seated posture, displacements of the rib cage during inspiration are in the cranial, lateral outward, and ventral directions but that expansion of the abdomen is confined to the ventral direction. PMID- 9375315 TI - Growth hormone, IGF-I, and exercise effects on non-weight-bearing fast muscles of hypophysectomized rats. AB - The effects of growth hormone (GH) or insulin-like growth factor I (IGF-I) with or without exercise (ladder climbing) in countering the effects of unweighting on fast muscles of hypophysectomized rats during 10 days of hindlimb suspension were determined. Compared with untreated suspended rats, muscle weights were 16-29% larger in GH-treated and 5-15% larger in IGF-I-treated suspended rats. Exercise alone had no effect on muscle weights. Compared with ambulatory control, the medial gastrocnemius weight in suspended, exercised rats was larger after GH treatment and maintained with IGF-I treatment. The combination of GH or IGF-I plus exercise in suspended rats resulted in an increase in size of each predominant fiber type, i.e., types I, I + IIa and IIa + IIx, in the medial gastrocnemius compared with untreated suspended rats. Normal ambulation or exercise during suspension increased the proportion of fibers expressing embryonic myosin heavy chain in hypophysectomized rats. The phenotype of the medial gastrocnemius was minimally affected by GH, IGF-I, and/or exercise. These results show that there is an IGF-I, as well as a GH, and exercise interactive effect in maintaining medial gastrocnemius fiber size in suspended hypophysectomized rats. PMID- 9375317 TI - Nitric oxide decreases lung liquid production in fetal lambs. AB - To examine the effect of nitric oxide on fetal lung liquid production, I measured lung liquid production in fetal sheep at 130 +/- 5 days gestation (range 122-137 days) before and after intrapulmonary instillation of nitric oxide. Thirty-one studies were done in which net lung luminal liquid production (JV) was measured by plotting the change in lung luminal liquid concentration of radiolabeled albumin, an impermeant tracer that was mixed into the lung liquid at the start of each study. To see whether changes in JV might be associated with changes in pulmonary hemodynamics, pulmonary and systemic pressures were measured and left pulmonary arterial flow was measured by an ultrasonic Doppler flow probe. Variables were measured during a 1- to 2-h control period and for 4 h after a small bolus of isotonic saline saturated with nitric oxide gas (10 or 100%) was instilled into the lung liquid. Control (saline) instillations (n = 6) caused no change in any variable over 6 h. Nitric oxide instillation significantly decreased JV and increased pulmonary blood flow; these effects were sustained for 1-2 h. There was also a significant but transient decrease in pulmonary arterial pressure. Thus intrapulmonary nitric oxide causes a significant decrease in lung liquid and is associated with a decrease in pulmonary vascular resistance. In a separate series of experiments either amiloride or benzamil, which blocks Na+ transport, was mixed into the lung liquid before nitric oxide instillation; still, there was a similar reduction in lung liquid production. Thus the reduction in lung liquid secretion caused by nitric oxide does not appear to depend on apical Na+ efflux. PMID- 9375318 TI - Inhibition of surfactant function by copper-zinc superoxide dismutase (CuZn-SOD). AB - The efficacy of antioxidant enzymes to limit oxidant lung injury by instillation with surfactant mixtures in preterm infants with hyaline membrane disease is under investigation. However, there is concern that instillation of proteins in the alveolar space may inactivate pulmonary surfactant. We studied the effects of bovine copper-zinc superoxide dismutase (CuZn-SOD) on the biophysical properties of two distinct surfactant preparations. Incubation of calf lung surfactant extract (CLSE, 1 mg phospholipid/ml) and Exosurf (0.1 mg phospholipid/ml) with CuZn-SOD (1-10 mg/ml) prevented the fall of surface tension at minimal bubble radius (Tmin) to low values with dynamic compression in a pulsating bubble surfactometer. CuZn-SOD also enhanced the sensitivity to inactivation by albumin, normal human serum, and after treatment with peroxynitrite. The inhibitory effects of CuZn-SOD on CLSE, but not Exosurf, were abolished at high lipid concentrations (3 mg/ml) and after the addition of human surfactant protein A (by weight). We conclude that CuZn-SOD may interfere with the surface activity of surfactant mixtures, leading to decreased effectiveness of surfactant replacement therapy. PMID- 9375319 TI - Effects of a training program on resting plasma 2-hydroxycatecholestrogen levels in eumenorrheic women. AB - Catecholestrogens (CE) represent a major metabolic pathway in estrogen metabolism. Previous information on CE and training is limited to two cross sectional studies that did not involve standardized training. Our purpose, by means of a prospective design, was to evaluate the effects of a brief, exhaustive training program on resting plasma concentrations of 2-hydroxy CE. The experimental design spanned two menstrual cycles; a control cycle and a training cycle. The subjects were nine previously untrained, eumenorrheic women [body fat: 24.8 +/- 1.0 (SE) %]. Data were collected during the follicular (FPh) and the luteal phases (LPh). Posttraining FPh and LPh tests were held the day after the last day of a 5-day period of training on a cycle ergometer. Total 2 hydroxyestrogens (2-OHE) averaged 200 +/- 29 pg/ml during the FPh and 420 +/- 54 pg/ml during the LPh (P < 0.05). Levels of total 2-methoxyestrogens (2-MeOE) were 237 +/- 32 pg/ml during the FPh and 339 +/- 26 pg/ml during the LPh (P < 0.05). After training, although the plasma levels of 2-OHE significantly decreased (21%; P < 0.05) during the LPh, the actual CE formation (as estimated from the 2-OHE-to total estrogens ratio) increased (+ 29%; P < 0.05). CE activity, as expressed by the 2-MeOE-to-2-OHE ratio, showed significantly higher values in both phases (FPh, + 14%; LPh, + 13%; P < 0.05). At the same time, resting levels of norepinephrine (NE) were increased by 42% (P < 0.05). CE strongly inhibit biological decomposition of NE by catechol-O-methyltransferase (COMT). Results of the present study suggest that, in response to training, CE are increasingly competing with the enzyme COMT, thus preventing premature NE deactivation. PMID- 9375320 TI - Mechanical behavior of skeletal muscle during intermittent voluntary isometric contractions in humans. AB - Changes in contractile speed and force-fusion properties were examined during repetitive isometric contractions with the knee extensors at three different target force levels. Seven healthy subjects were studied at target force levels of 30, 45, and 60% of their maximal voluntary contraction (MVC) force. Repeated 6 s contractions followed by 4-s rest were continued until exhaustion. Contractile speed was determined for contractions elicited by electrical stimulation at 1-50 Hz given during exercise and a subsequent 27-min recovery period. Contraction time remained unchanged during exercise and recovery, except for an initial rapid shift in the twitch properties. Half relaxation time (RT1/2) decreased gradually by 20-40% during exercise at 30 and 45% of MVC. In the recovery period, RT1/2 values were not fully restored to preexercise levels. During exercise at 60% MVC, the RT1/2 decreased for twitches and increased for the 50-Hz stimulation. In the recovery period after 60% MVC, RT1/2 values declined toward those seen after the 30 and 45% MVC exercise. The force oscillation amplitude in unfused tetani relative to the mean force increased during exercise at 30 and 45% MVC but remained unaltered during the 60% MVC exercise. This altered force-fusion was closely associated with the changes in RT1/2. The faster relaxation may at least partly explain the increased energy cost of contraction reported previously for the same type of exercise. PMID- 9375321 TI - Glucose modulates hemodynamic, metabolic, and inflammatory responses to lipopolysaccharide in rabbits. AB - Glucose is important for vascular and immunocompetent cell functions. We hypothesized that modifications in glucose metabolism (normal feeding, 24-h fasting, glucose loading) may influence the hemodynamic, metabolic, and inflammatory responses to lipopolysaccharide administration (LPS; 600 micrograms/kg iv) in rabbits. Aortic (ABFV), hepatic artery (HABFV), and portal vein blood flow velocities (PVBFV) (pulsed Doppler), plasma tumor necrosis factor (TNF) and nitrites were measured. Fasting depleted hepatic glycogen content, and intraportal glucose load (2 g/kg) partially restored it. LPS induced a similar hypotension (-20%, P < 0.05) in three groups of animals. In fed animals, systemic vasoconstriction occurred with low ABFV and PVBFV (-40%, P < 0.05), together with lactacidemia and hyperglycemia. In fasted animals, ABFV and PVBFV were maintained, without metabolic acidosis or hyperglycemia. Glucose loading induced hemodynamic and metabolic patterns comparable to those observed in fed animals, although significantly more severe. TNF release was amplified fourfold by glucose loading, with no impact on nitrite levels. In conclusion, glucose metabolism interferes with hemodynamic, metabolic, and inflammatory responses to LPS. PMID- 9375322 TI - Sympathetic vasoconstriction in active skeletal muscles during dynamic exercise. AB - Studies utilizing systemic administration of alpha-adrenergic antagonists have failed to demonstrate sympathetic vasoconstriction in working muscles during dynamic exercise. The purpose of this study was to examine the existence of active sympathetic vasoconstriction in working skeletal muscles by using selective intra-arterial blockade. Six mongrel dogs were instrumented chronically with flow probes on the external iliac arteries of both hindlimbs and with a catheter in one femoral artery. All dogs ran on a motorized treadmill at three intensities on separate days. After 2 min, the selective alpha 1-adrenergic antagonist prazosin (0.1 mg) was infused as a bolus into the femoral artery catheter. At mild, moderate, and heavy workloads, there were immediate increases in iliac conductance of 76 +/- 7, 54 +/- 11, and 22 +/- 6% (mean +/- SE), respectively. Systemic blood pressure and blood flow in the contralateral iliac artery were unaffected. These results demonstrate that there is sympathetic vasoconstriction in active skeletal muscles even at high exercise intensities. PMID- 9375323 TI - Age and gender comparisons of muscle strength in 654 women and men aged 20-93 yr. AB - To assess age and gender differences in muscle strength, isometric, concentric (Con), and eccentric (Ecc) peak torque was measured in the knee extensors at a slow (0.52 rad/s) and fast (3.14 rad/s) velocity in 654 subjects (346 men and 308 women, aged 20-93 yr) from the Baltimore Longitudinal Study of Aging. Regression analysis revealed significant (P < 0.001) age-related reductions in Con and Ecc peak torque for men and women at both velocities, but no differences were observed between the gender groups or velocities. Age explained losses in Con better than Ecc peak torque, accounting for 30% (Con) vs. 19% (Ecc) of the variance in men and 28% (Con) vs. 11% (Ecc) in women. To assess age and gender differences in the ability to store and utilize elastic energy, the stretch shortening cycle was determined in a subset of subjects (n = 47). The older women (mean age = 70 yr) showed a significantly greater enhancement in the stretch shortening cycle, compared with men of similar age (P < 0.01) and compared with younger men and women (each P < 0.05). Both men and women showed significant declines in muscle quality for Con peak torque (P < 0.01), but no gender differences were observed. Only the men showed a significant decline in muscle quality (P < 0.001) for Ecc peak torque. Thus both men and women experience age related losses in isometric, Con, and Ecc knee extensor peak torque; however, age accounted for less of the variance in Ecc peak torque in women, and women tend to better preserve muscle quality with age for Ecc peak torque. In addition, older women have an enhanced capacity to store and utilize elastic energy compared with similarly aged men as well as with younger women and men. PMID- 9375324 TI - Respiratory-related pharyngeal constrictor muscle activity in decerebrate cats. AB - Respiratory-related activity of the hyopharyngeus (middle pharyngeal constrictor) and thyropharyngeus (inferior pharyngeal constrictor) muscles was determined in decerebrate, tracheotomized adult cats and compared with the electromyographic activity of the thyroarytenoid, a vocal cord adductor. During quiet breathing, the hyopharyngeus and usually the thyroarytenoid exhibited phasic activity during expiration and tonic activity throughout the respiratory cycle. Respiratory related thyropharyngeus activity was absent under these conditions. Progressive hyperoxic hypercapnia and progressive isocapnic hypoxia increased phasic expiratory activity in both pharyngeal constrictor (PC) muscles but tended to suppress thyroarytenoid activity. Passively induced hypocapnia and the central apnea that followed the cessation of the mechanical hyperventilation were associated with tonic activation of the hyopharyngeus and thyroarytenoid but no recruitment in thyropharyngeus activity. The expiratory phase of a sigh and progressive pneumothorax were associated with an increase in phasic thyroarytenoid activity but no change in phasic PC activity. The results indicate that a variety of stimuli modulate respiratory-related PC activity, suggesting that the PC muscles may have a role in the regulation of upper airway patency during respiration. PMID- 9375325 TI - Mechanical impedance of the lung periphery. AB - The mechanics of the regional airways and tissues was studied in isolated dog lobes by means of a modified wave-tube technique. Small-amplitude pseudorandom forced oscillations between 0.1 and 48 Hz were applied through catheters wedged in 2-mm-diameter bronchi in three regions of each lobe at translobar pressures (PL) of 10, 7, 5, 3, 2, and 1 cmH2O. The measured regional input impedances were fitted by a model containing the resistance (R1) and inertance (I) of the regular (segmental) airways, the resistance of the collateral channels (R2), and the damping (G) and elastance (H) of the local tissues. This model gave far better fits to the data on impedance of the lung periphery than when G and H were replaced by a single tissue compliance, which explains why interruption of segmental flow did not lead to monoexponential pressure decay in previous studies. The interlobar and intralobar variances of the parameters were equally significant, and poor correlations were found between the airway parameters R1 and R2 and between any airway and tissue parameter (e.g., R1 and H). R2 was on average approximately 10 times higher than R1, although the R2-to-R1 ratios and their dependencies on PL were regionally highly variable. However, for the total of 33 regions studied, the PL dependence was the same for R1 and R2, which may reflect similar morphological structures for the regular and collateral airways. The dependencies of G and H on PL showed high interregional variations; generally, however, they assumed their minima at medium PL values (approximately 5 cmH2O). PMID- 9375326 TI - Protoveratrines A and B increase sleep apnea index in Sprague-Dawley rats. AB - The action of protovertarines A and B, which stimulate carotid sinus baroreceptors and vagal sensory endings in the heart as well as pulmonary bed, were assessed on spontaneous and postsigh central sleep apneas in freely moving Sprague-Dawley rats. During the 6-h recording period, animals were simultaneously monitored for sleep by using electroencephalogram and electromyogram recordings, for respiration by single-chamber plethysmography, and for blood pressure and heart period by using radiotelemetry. After administration of 0.2, 0.5, or 1 mg/kg sc of protoveratrines, cardiopulmonary changes lasting at least 6 h were observed in all three behavioral states [heart period increased up to 23% in wakefulness, 21% in non-rapid-eye-movement (non-REM) sleep, and 20% in REM sleep; P < 0.005 for each]. At the same time, there was a substantial increase in the number of spontaneous (375% increase; P = 0.04) and postsigh (268% increase, P = 0.0002) apneas. Minute ventilation decreased by up to 24% in wakefulness, 25% in non-REM, and 35% in REM sleep (P < 0.05 for each). We conclude that pharmacological stimulation of baroreflexes promotes apnea expression in the sleeping rat. PMID- 9375327 TI - Vagal stimulation induces expiratory lengthening in the in vitro neonate rat. AB - Respiration is modulated by lung mechanoreceptor feedback in vivo on a cycle-to cycle basis. We replicated this modulation in vitro and tested four stimulus protocols to identify which of these most closely replicated in vivo responses to lung mechanoreceptor activation in mammals. We activated pulmonary vagal afferent pathways by electrical stimulation or by lung inflation, applied during expiration, which produces expiratory lengthening in vivo. In each modality, transient and tonic stimuli were applied. Stimuli were applied over a range of delays following inspiratory termination. Tonic stimuli were maintained until subsequent inspiratory onset. All stimulus modalities prolonged expiration (P < 0.05). These results indicate that the neural circuitry mediating pulmonary afferent modulation of expiratory duration is retained in vitro. PMID- 9375328 TI - Influence of nicotine on the core temperature response to a novel environment in pregnant rats. AB - Exposure of a male or nonpregnant female rat to a novel environment, such as a simulated open field, induces a transient increase in core temperature, which is often called stress-induced hyperthermia. Pregnancy alters this response such that the core temperature index increases significantly during exposure to a simulated open field on day 10 but not on days 15 and 20 of gestation in rats. The present experiments were carried to investigate the effect of chronic administration of nicotine (0, 1, 2, 4, or 8 mg.kg-1.24 h-1 for 13-15 days) on the core temperature response to a simulated open field in chronically instrumented pregnant (day 20 or 21 of gestation) and nonpregnant Sprague-Dawley rats. In nonpregnant rats, the core temperature index increased more during exposure to a simulated open field after chronic administration of nicotine at all doses than after chronic administration of vehicle; the core temperature response was not dependent on the dose of nicotine. In pregnant rats, significant increases in core temperature as well as in the core temperature index occurred only during exposure to a simulated open field after chronic administration of nicotine in doses of 2, 4, or 8 mg.kg-1.24 h-1; the core temperature response was dependent on the dose of nicotine. Our data provide evidence that chronic exposure to nicotine enhances the core temperature response to a simulated open field in nonpregnant rats and unmasks a maternal thermogenic response that is not seen to the same stimulus near term of pregnancy. The possible physiological consequences for the fetus are presently unknown and require investigation. PMID- 9375330 TI - Glucose transporter content and enzymes of metabolism in nerve-repair grafted muscle of aging Fischer 344 rats. AB - Aging and grafting are associated with decreased ability of muscle to sustain power, likely reflecting diminished fuel availability. To assess mechanisms that may contribute to availability of glucose, we studied GLUT-1 and GLUT-4 protein as well as mRNA contents and enzymes of glucose metabolism in grafted and control medial gastrocnemius (MG) muscles of 6-, 12-, and 24-mo-old male Fischer 344 rats. There was no effect of age or grafting on MG GLUT-4 content. There was both an age- and graft-associated increase in GLUT-1 content (P = 0.0044 and 0.0063, respectively). There was no effect of aging or grafting on hexokinase and phosphofructokinase activity or on protein and glycogen content. Muscle mass and citrate synthase activity were significantly diminished with grafting. Citrate synthase activity was significantly greater in the 12-mo-old compared with the 6- and 24-mo-old animals. Grafting in combination with aging had no impact on any of the parameters measured. We conclude that diminished glucose transporter expression cannot explain the decreased ability of aged muscle to sustain power. In addition, we conclude that the diminished ability of the grafted MG muscle to sustain power may be explained, in part, by a decrease in energy available from oxidative metabolism. PMID- 9375331 TI - Inhibition of shivering increases core temperature afterdrop and attenuates rewarming in hypothermic humans. AB - During severe hypothermia, shivering is absent. To simulate severe hypothermia, shivering in eight mildly hypothermic subjects was inhibited with meperidine (1.5 mg/kg). Subjects were cooled twice (meperidine and control trials) in 8 degrees C water to a core temperature of 35.9 +/- 0.5 (SD) degrees C, dried, and then placed in sleeping bags. Meperidine caused a 3.2-fold increase in core temperature afterdrop (1.1 +/- 0.6 vs. 0.4 +/- 0.2 degree C), a 4.3-fold increase in afterdrop duration (89.4 +/- 31.4 vs. 20.9 +/- 5.7 min), and a 37% decrease in rewarming rate (1.2 +/- 0.5 vs. 1.9 +/- 0.9 degrees C/h). Meperidine inhibited overt shivering. Oxygen consumption, minute ventilation, and heart rate decreased after meperidine injection but subsequently returned toward preinjection values after 45 min postimmersion. This was likely due to the increased thermoregulatory drive with the greater afterdrop and the short half-life of meperidine. These results demonstrate the effectiveness of shivering heat production in attenuating the postcooling afterdrop of core temperature and potentiating core rewarming. The meperidine protocol may be valuable for comparing the efficacy of various hypothermia rewarming methods in the absence of shivering. PMID- 9375332 TI - Efficacy of forced-air and inhalation rewarming by using a human model for severe hypothermia. AB - We recently developed a nonshivering human model for severe hypothermia by using meperidine to inhibit shivering in mildly hypothermic subjects. This thermal model was used to evaluate warming techniques. On three occasions, eight subjects were immersed for approximately 25 min in 9 degrees C water. Meperidine (1.5 mg/kg) was injected before the subjects exited the water. Subjects were then removed, insulated, and rewarmed in an ambient temperature of -20 degrees C with either 1) spontaneous rewarming (control), 2) inhalation rewarming with saturated air at approximately 43 degrees C, or 3) forced-air warming. Additional meperidine (to a maximum cumulative dose of 2.5 mg/kg) was given to maintain shivering inhibition. The core temperature afterdrop was 30-40% less during forced-air warming (0.9 degree C) than during control (1.4 degrees C) and inhalation rewarming (1.2 degrees C) (P < 0.05). Rewarming rate was 6- to 10-fold greater during forced-air warming (2.40 degrees C/h) than during control (0.41 degree C/h) and inhalation rewarming (0.23 degree C/h) (P < 0.05). In nonshivering hypothermic subjects, forced-air warming provided a rewarming advantage, but inhalation rewarming did not. PMID- 9375329 TI - Flow-induced responses in cat isolated pulmonary arteries. AB - Isolated, cannulated, endothelium-intact cat pulmonary arteries, averaging 692 +/ 104 microns in diameter, were set at a transmural pressure of 10 mmHg and monitored with a video system. Intraluminal flow was increased in steps from 0 to 1.6 ml/min by using a syringe pump. An electronic system held pressure constant by changing outflow resistance. Flow-diameter curves were generated in physiological saline solution. At constant transmural pressure, the arteries constricted in response to increased intraluminal flow. Constriction was not affected by removing extracellular Ca2+ but was abolished after treatment with ryanodine to deplete intracellular Ca2+ stores, with the endothelin-1 synthesis inhibitor phosphoramidon, with the endothelin A-receptor antagonist BQ-123, with the protein kinase C inhibitor staurosporine, or with glutaraldehyde to reduce endothelial cell deformability. The results indicate that isolated pulmonary arteries can constrict in response to intraluminal flow and suggest that constriction is mediated by endothelin-1 and depends on intracellular Ca2+ release and protein kinase C activation. PMID- 9375333 TI - Effect of supplemental oxygen on supramaximal exercise performance and recovery in cystic fibrosis. AB - The effects of supplemental O2 on recovery from supramaximal exercise and subsequent performance remain unknown. If recovery from exercise could be enhanced in individuals with chronic lung disease, subsequent supramaximal exercise performance could also be improved. Recovery from supramaximal exercise and subsequent supramaximal exercise performance were assessed after 10 min of breathing 100% O2 or room air (RA) in 17 cystic fibrosis (CF) patients [25 +/- 10 (SD) yr old, 53% men, forced expired volume in 1 s = 62 +/- 21% predicted] and 17 normal subjects (25 +/- 8 yr old, 59% men, forced expired volume in 1 s = 112 +/- 15% predicted). Supramaximal performance was assessed as the work of sustained bicycling at a load of 130% of the maximum load achieved during a graded maximal exercise. Peak minute ventilation (VE) and heart rate (HR) were lower in CF patients at the end of each supramaximal bout than in controls. In CF patients, single-exponential time decay constants indicated faster recovery of HR (tau HR = 86 +/- 8 and 73 +/- 6 s in RA and O2, respectively, P < 0.01). Similarly, fast and slow time constants of two-exponential equations providing the best fit for ventilatory recovery were improved in CF patients during O2 breathing (tau 1VE = 132.1 +/- 10.5 vs. 82.5 +/- 10.4 s; tau 2VE = 880.3 +/- 300.1 vs. 368.6 +/- 107.1 s, P < 0.01). However, no such improvements occurred in controls. Supramaximal performance after O2 improved in CF patients (109 +/- 6% of the 1st bout after O2 vs. 94 +/- 6% in RA, P < 0.01). O2 supplementation had no effect on subsequent performance in controls (97 +/- 3% in O2 vs. 93 +/- 3% in RA). We conclude that supplemental O2 after a short bout of supramaximal exercise accelerates recovery and preserves subsequent supramaximal performance in patients with CF. PMID- 9375334 TI - Blood flow, vascular resistance, and blood volume after hemorrhage in conscious adrenalectomized rat. AB - Hemorrhage leads to cardiovascular collapse and death in adrenal-insufficient animals. To determine whether the cardiovascular collapse is due to vasodilation and/or failure to restore blood volume, we used radiolabeled microspheres and 125I-labeled albumin to measure blood flow and blood volume in conscious adrenalectomized (ADX) rats after 15 ml.kg-1.3 min-1 hemorrhage. In ADX rats, hemorrhage led to a greater fall than in sham rats in blood flow in the stomach, small intestines, cecum, colon, spleen, hepatic portal vein, kidney, testis, lung, thymus, bone, fat, forebrain, cerebellum, and brainstem. The greater fall in blood flow was caused by an increase in vascular resistance in these organs except brain and hepatic artery. Sham rats maintained or increased brain and hepatic artery blood flow after hemorrhage whereas flow decreased and remained depressed in ADX rats. ADX rats failed to restore blood volume, whereas sham rats completely restored blood flow by 2 h. We conclude that cardiovascular collapse in ADX rats does not result from vasodilatation but may result from a failure to restore blood volume. The failure to restore blood volume and the low blood flow to organs, especially brain and liver, may contribute to mortality in ADX rats after hemorrhage. PMID- 9375335 TI - Ultrasound evaluation of piglet diaphragm function before and after fatigue. AB - Clinically, a noninvasive measure of diaphragm function is needed. The purpose of this study is to determine whether ultrasonography can be used to 1) quantify diaphragm function and 2) identify fatigue in a piglet model. Five piglets were anesthetized with pentobarbital sodium and halothane and studied during the following conditions: 1) baseline (spontaneous breathing); 2) baseline + CO2 [inhaled CO2 to increase arterial PCO2 to 50-60 Torr (6.6-8 kPa)]; 3) fatigue + CO2 (fatigue induced with 30 min of phrenic nerve pacing); and 4) recovery + CO2 (recovery after 1 h of mechanical ventilation). Ultrasound measurements of the posterior diaphragm were made (inspiratory mean velocity) in the transverse plane. Images were obtained from the midline, just inferior to the xiphoid process, and perpendicular to the abdomen. M-mode measures were made of the right posterior hemidiaphragm in the plane just lateral to the inferior vena cava. Abdominal and esophageal pressures were measured and transdiaphragmatic pressure (Pdi) was calculated during spontaneous (Sp) and paced (Pace) breaths. Arterial blood gases were also measured. Pdi(Sp) and Pdi(Pace) during baseline + CO2 were 8 +/- 0.7 and 49 +/- 11 cmH2O, respectively, and decreased to 6 +/- 1.0 and 27 +/ 7 cmH2O, respectively, during fatigue + CO2. Mean inspiratory velocity also decreased from 13 +/- 2 to 8 +/- 1 cm/s during these conditions. All variables returned to baseline during recovery + CO2. Ultrasonography can be used to quantify diaphragm function and identify piglet diaphragm fatigue. PMID- 9375336 TI - Changes in stroke volume with beta-blockade before and after 10 days of exercise training in men and women. AB - We sought to determine whether 10 days of training would be a sufficient stimulus for cardiac adaptations that would allow a greater compensatory stroke volume during beta-blockade. We also sought to determine whether men and women had a similar cardiac reserve capacity for increasing stroke volume with beta-blockade during submaximal exercise. Eight men (age 29 +/- 2 yr, mean +/- SE) and eight women (25 +/- 2 yr) cycled at 65% of peak O2 consumption (unblocked) under placebo-control and beta-blockade (100 mg atenolol) conditions performed on separate days. These tests were repeated at the same power output after training (10 consecutive days, 1 h of cycling per day). Before training, beta-blockade significantly (P < 0.05) decreased heart rate (HR) and cardiac output and increased stroke volume in both men and women. After training, the increase in stroke volume and decrease in HR with beta-blockade was significantly less while cardiac output was reduced more. There were no gender differences in the effects of beta-blockade on HR, stroke volume, or cardiac output. These data indicate that, during exercise with beta-blockade, exercise training for 10 days does not enhance the compensatory increase in stroke volume and that men and women have a similar cardiac reserve capacity for increasing stroke volume. PMID- 9375337 TI - Partial liquid ventilation protects lung during resuscitation from shock. AB - Preliminary animal experience with partial liquid ventilation (PLV) suggests that this therapy may diminish neutrophil invasion and capillary leak during acute lung injury. We sought to confirm these findings in a model of shock-induced lung injury. Sixty anesthetized rats were studied. After hemorrhage to an arterial pressure of 25 mmHg for 45 min, animals were resuscitated with blood and saline and treated with gas ventilation alone or with 5 ml/kg of intratracheally administered perflubron. Myeloperoxidase activity was used to measure lung neutrophil content. A permeability index (the bronchoalveolar-to-blood ratio of 125I-labeled albumin activity) quantified alveolar leak. Injury caused an increase in myeloperoxidase that was reversed by PLV (injury = 0.837 +/- 0.452, PLV = 0.257 +/- 0.165; P < 0.01). Capillary permeability also increased with hemorrhage, with a strong trend toward improvement in the PLV group (permeability indexes: injury = 0.094 +/- 0.102, PLV = 0.045 +/- 0.045; 95% confidence interval for injury--PLV: -0.024, 0.1219). We conclude that PLV is associated with a decrease in pulmonary neutrophil accumulation and a trend toward decreased capillary leak after hemorrhagic shock. PMID- 9375338 TI - Systemic and pulmonary hemodynamic responses to normal and obstructed breathing during sleep. AB - We examined the hemodynamic responses to normal breathing and induced upper airway obstructions during sleep in a canine model of obstructive sleep apnea. During normal breathing, cardiac output decreased (12.9 +/- 3.5%, P < 0.025) from wakefulness to non-rapid-eye-movement sleep (NREM) but did not change from NREM to rapid-eye-movement (REM) sleep. There was a decrease (P < 0.05) in systemic (7.2 +/- 2.1 mmHg) and pulmonary (2.0 +/- 0.6 mmHg) arterial pressures from wakefulness to NREM sleep. In contrast, systemic (8.1 +/- 1.0 mmHg, P < 0.025), but not pulmonary, arterial pressures decreased from NREM to REM sleep. During repetitive airway obstructions (56.0 +/- 4.7 events/h) in NREM sleep, cardiac output (17.9 +/- 3.1%) and heart rate (16.2 +/- 2.5%) increased (P < 0.05), without a change in stroke volume, compared with normal breathing during NREM sleep. During single obstructive events, left (7.8 +/- 3.0%, P < 0.05) and right (7.1 +/- 0.7%, P < 0.01) ventricular outputs decreased during the apneic period. However, left (20.7 +/- 1.6%, P < 0.01) and right (24.0 +/- 4.2%, P < 0.05) ventricular outputs increased in the post-apneic period because of an increase in heart rate. Thus 1) the systemic, but not the pulmonary, circulation vasodilates during REM sleep with normal breathing; 2) heart rate, rather than stroke volume, is the dominant factor modulating ventricular output in response to apnea; and 3) left and right ventricular outputs oscillate markedly and in phase throughout the apnea cycle. PMID- 9375339 TI - Raising P50 increases tissue PO2 in canine skeletal muscle but does not affect critical O2 extraction ratio. AB - Affinity of hemoglobin (Hb) for O2 determines in part the rate of O2 diffusion from capillaries to myocytes by altering capillary PO2. We hypothesized that a decrease in Hb O2 affinity (increased P50) would increase capillary and tissue PO2 (PtiO2) and improve O2 consumption during ischemia. To test this hypothesis, blood flow to the pump-perfused left hindlimb of 18 anesthetized and paralyzed dogs was progressively decreased over 90 min while hindlimb O2 consumption and O2 delivery (QO2) and PtiO2 were measured at the muscle surface. Arterial PO2 was maintained at 150 +/- 10 Torr in all dogs. We increased P50 by 12.3 +/- 0.9 (SE) Torr in nine dogs with RSR-13, an allosteric modifier of Hb. This decreased arterial O2 saturation to 90-92% but increased mean PtiO2 from 35.5 +/- 11.6 to 44.1 +/- 15.2 (SD) Torr (P < 0.05) with no change in controls (n = 9). O2 extraction ratio at critical QO2 was 74 +/- 2% in controls and 79 +/- 1% in RSR 13-treated dogs (P = not significant). PtiO2 was 30-40% higher in the RSR-13 treated group at any QO2 above critical but did not differ between groups below critical QO2. Perfusion heterogeneity and convergence of the dissociation curves near critical QO2 may have mitigated any effect of increased P50 on O2 diffusion. Still, increasing P50 by 12 Torr with RSR-13 significantly increased PtiO2 at QO2 values above critical. PMID- 9375340 TI - Determination of airway and tissue resistances after antigen and methacholine in nonhuman primates. AB - Antigen challenge of Ascaris suum-sensitive animals has been used as a model of asthma in humans. However, no reports have separated total respiratory resistance into airway (Raw) and tissue (Rti) components. We compared input impedance (Zin) and transfer impedance (Ztr) to determine Raw and Rti in anesthetized cynomolgus monkeys under control and bronchoconstricted conditions. Zin data between 1 and 64 Hz are frequency dependent during baseline conditions, and this frequency dependence shifts in response to A. suum or methacholine. Thus it cannot be modeled with the DuBois model, and estimates of Raw and Rti cannot be determined. With Ztr, baseline data were much less variable than Zin in all monkeys. After bronchial challenge with A. suum or methacholine, the absolute amplitude of the resistive component of Ztr increased and its zero crossing shifted to higher frequencies. These data can estimate Raw and Rti with the six-element DuBois model. Therefore, in monkeys, Ztr has advantages over other measures of lung function, since it provides a methodology to separate estimates of Raw and Rti. In conclusion, Ztr shows spectral features similar to those reported in healthy and asthmatic humans. PMID- 9375341 TI - High vascular and airway pressures increase interstitial protein mRNA expression in isolated rat lungs. AB - We hypothesized that wall stresses produced by high peak airway (Paw) and venous (Ppv) pressures would increase mRNA levels for structural proteins of the interstitial matrix in isolated rat lungs. Groups of lungs (n = 6) were perfused for 4 h at a peak Paw of 35 cmH2O (HiPaw), cyclical peak Ppv of 28 cmH2O (HiPv), or baseline vascular and airway pressures (LoPress). In two separate groups, comparable peak pressures increased capillary filtration coefficient fourfold in each group. Northern blots were probed for mRNA of alpha 1(I), alpha 1(III), and alpha 2(IV) procollagen chains, laminin B chain, fibronectin, and transforming growth factor-beta 1, and densities were normalized to 18S rRNA. mRNA was significantly higher in the HiPv group for type I (4.3-fold) and type III (3.8 fold) procollagen and laminin B chain (4.8-fold) and in the HiPaw group for type I (2.4-fold) and type IV (4.5-fold) procollagen and laminin B chain (2.3-fold) than in the LoPress group. Only fibronectin mRNA was significantly increased (3.9 fold) in the LoPress group relative to unperfused lungs. Estimated wall stresses were highest for alveolar septa in the HiPaw group and for capillaries in the HiPv group. The different patterns of mRNA expression are attributed to different regional stresses or extent of injury. PMID- 9375342 TI - Role of endogenous female hormones in hypoxic chemosensitivity. AB - Effective alveolar ventilation and hypoxic ventilatory response (HVR) are higher in females than in males and after endogenous or exogenous elevation of progesterone and estrogen. The contribution of normal physiological levels of ovarian hormones to resting ventilation and ventilatory control and whether their site(s) of action is central and/or peripheral are unclear. Accordingly, we examined resting ventilation, HVR, and hypercapnic ventilatory responses (HCVR) before and 3 wk after ovariectomy in five female cats. We also compared carotid sinus nerve (CSN) and central nervous system translation responses to hypoxia in 6 ovariectomized and 24 intact female animals. Ovariectomy decreased serum progesterone but did not change resting ventilation, end-tidal PCO2, or HCVR (all P = NS). Ovariectomy reduced the HVR shape parameter A in the awake (38.9 +/- 5.5 and 21.2 +/- 3.0 before and after ovariectomy, respectively, P < 0.05) and anesthetized conditions. The CSN response to hypoxia was lower in ovariectomized than in intact animals (shape parameter A = 22.6 +/- 2.5 and 54.3 +/- 3.5 in ovariectomized and intact animals, respectively, P < 0.05), but central nervous system translation of CSN activity into ventilation was similar in ovariectomized and intact animals. We concluded that ovariectomy decreased ventilatory and CSN responsiveness to hypoxia, suggesting that the presence of physiological levels of ovarian hormones influences hypoxic chemosensitivity by acting primarily at peripheral sites. PMID- 9375343 TI - Effects of anatomic variability on blood flow and pressure gradients in the pulmonary capillaries. AB - A theoretical model is developed to simulate the flow of blood through the capillary network in a single alveolar septum. The objective is to study the influence of random variability in capillary dimension and compliance on flow patterns and pressures within the network. The capillary bed is represented as an interconnected rectangular grid of capillary segments and junctions; blood flow is produced by applying a pressure gradient across the network. Preferred flow channels are shown to be a natural consequence of random anatomic variability, the effect of which is accentuated at low transcapillary pressures. The distribution of pressure drops across single capillary segments widens with increasing network variability and decreasing capillary transmural pressure. Blockage of one capillary segment causes the pressure drop across that segment to increase by 60%, but the increase falls to < 10% at a distance of three segments. The factors that cause nonuniform capillary blood flow through the capillary network are discussed. PMID- 9375344 TI - Wave-speed-determined flow limitation at peak flow in normal and asthmatic subjects. AB - The purpose of this study was to examine whether peak expiratory flow is determined by the wave-speed flow-limiting mechanism. We examined 17 healthy subjects and 11 subjects with stable asthma, the latter treated with inhaled bronchodilators and corticosteroids. We used an esophageal balloon and a Pitot static probe positioned at five locations between the right lower lobe and midtrachea to obtain dynamic area-transmural pressure (A-Ptm) curves as described (O. F. Pedersen, B. Thiessen, and S. Lyager. J. Appl. Physiol. 52: 357-369, 1982). From these curves we obtained cross-sectional area (A) and airway compliance (Caw = dA/dPtm) at PEF, calculated flow at wave speed (Vws = A[A/(Caw*rho)0.5], where rho is density) and speed index is (SI = V/Vws). In 13 of 15 healthy and in 4 of 10 asthmatic subjects, who could produce satisfactory curves, SI at PEF was > 0.9 at one or more measured positions. Alveolar pressure continued to increase after PEF was achieved, suggesting flow limitation somewhere in the airway in all of these subjects. We conclude that wave speed is reached in central airways at PEF in most subjects, but it cannot be excluded that wave speed is also reached in more peripheral airways. PMID- 9375346 TI - Stretch-induced enhancement of mechanical work production in frog single fibers and human muscle. AB - The relations between the velocity of prestretch and the mechanical energy liberated during the subsequent isovelocity release were studied in contractions of frog single fibers and human muscles. During isometric contractions of frog single fibers, a ramp stretch of varied velocity (amplitude, 0.02 fiber length; velocity, 0.08-1.0 fiber length/s) followed by a release (amplitude, 0.02 fiber length; velocity, 1.0 fiber length/s) was given, and the amount of work liberated during the release was measured. For human muscles, elbow flexions were performed with a prestretch of varied velocity (range, 40 degrees; velocity, 30-180 degrees/s) followed by an isokinetic shortening (velocity, 90 degrees/s). In both frog single fibers and human muscles, the work production increased with both the velocity of stretch and the peak of force attained before the release up to a certain level; thereafter it declined with the further increases of these variables. In human muscles, the enhancement of work production was not associated with a significant increase in integrated electromyogram. This suggests that changes in intrinsic mechanical properties of muscle fibers play an important role in the stretch-induced enhancement of work production. PMID- 9375345 TI - Recovery of diaphragmatic function in awake sheep after two approaches to thoracic surgery. AB - Video-assisted thoracoscopic surgery (VATS) is replacing thoracotomy, but no study has addressed the extent or duration of VATS-induced diaphragmatic alteration. We hypothesized that VATS would impair diaphragmatic function less and return diaphragmatic function faster than thoracotomy. In eight sheep, sonomicrometers were randomly implanted on the right costal diaphragm via VATS or thoracotomy. Diaphragmatic resting length, shortening fraction, and respiratory function were measured weekly during quiet breathing (QB) and CO2 rebreathing for 4 wk. For VATS, shortening fraction was smallest on postoperative days 1 (POD 1) (6.4 +/- 3.4 and 12.9 +/- 8.7% during QB and 10% CO2 rebreathing, respectively) and 7 (6.3 +/- 3.4 and 16.9 +/- 4.0% during QB and 10% CO2 rebreathing, respectively) and recovered by 3 wk (13.2 +/- 1.8 and 28.9 +/- 8.0% during QB and 10% CO2 rebreathing, respectively). For thoracotomy, shortening fraction at 10% CO2 rebreathing was smaller on PODs 1, 7, 14 (15.9 +/- 7.1, 13.6 +/- 5.4, and 19.0 +/- 6.9%) than on POD 28 (29.9 +/- 8.2%), but not during QB on POD 1 or 7 (7.5 +/- 3.8 and 3.4 +/- 2.6%) compared with POD 28 (10.7 +/- 8.7%). Shortening fraction did not differ between surgeries. There was no group difference in minute ventilation, respiratory rate, transdiaphragmatic pressure, or esophageal and gastric pressures. In conclusion, although shortening fraction recovered faster for VATS, this translated into insignificant functional differences. PMID- 9375347 TI - Stretch-induced enhancement of mechanical power output in human multijoint exercise with countermovement. AB - The relation between the eccentric force developed during a countermovement and the mechanical power output was studied in squatting exercises under nominally isotonic load (50% of 1-repetition maximum). The subjects (n = 5) performed squatting exercises with a countermovement at varied deceleration rates before lifting the load. The ground reaction force and video images were recorded to obtain the power output of the body. Net muscle moments acting at hip, knee, and ankle joints were calculated from video recordings by using inverse dynamics. When an intense deceleration was taken at the end of downward movement, large eccentric force was developed, and the mechanical power subsequently produced during the lifting movement was consistently larger than that produced without the countermovement. Both maximal and mean power outputs during concentric actions increased initially with the eccentric force, whereas they began to decline when the eccentric force exceeded approximately 1.4 times the sum of load and body weight. Video-image analysis showed that this characteristic relation was predominantly determined by the torque around the knee joint. Electromyographic analyses showed no consistent increase in time-averaged integrated electromyograph from vastus lateralis with the power output, suggesting that the enhancement of power output is primarily caused by the prestretch-induced improvement of an intrinsic force-generating capability of the agonist muscle. PMID- 9375349 TI - Monitoring changes in lung air and liquid volumes with electrical impedance tomography. AB - Electrical impedance tomography (EIT) uses electrical measurements at electrodes placed around the thorax to image changes in the conductivity distribution within the thorax. This technique is well suited to studying pulmonary function because the movement of air, blood, and extravascular fluid induces significant conductivity changes within the thorax. We conducted three experimental protocols in a total of 19 dogs to assess the accuracy with which EIT can quantify changes in the volumes of both gas and fluid in the lungs. In the first protocol, lung volume increments from 50 to 1,000 ml were applied with a large syringe. EIT measured these volume changes with an average error of 27 +/- 6 ml. In the second protocol, EIT measurements were made at end expiration and end inspiration during regular ventilation with tidal volume ranging from 100 to 1,000 ml. The average error in the EIT estimates of tidal volume was 90 +/- 43 ml. In the third protocol, lung liquid volume was measured by instilling 5% albumin solution into a lung lobe in increments ranging from 10 to 100 ml. EIT measured these volume changes with an average error of 10 +/- 10 ml and was also able to detect into which lobe the fluid had been instilled. These results indicate that EIT can noninvasively measure changes in the volumes of both gas and fluid in the lungs with clinically useful accuracy. PMID- 9375348 TI - Human growth hormone response to repeated bouts of aerobic exercise. AB - We examined whether repeated bouts of exercise could override growth hormone (GH) auto-negative feedback. Seven moderately trained men were studied on three occasions: a control day (C), a sequential exercise day (SEB; at 1000, 1130, and 1300), and a delayed exercise day (DEB; at 1000, 1400, and 1800). The duration of each exercise bout was 30 min at 70% maximal O2 consumption (VO2max) on a cycle ergometer. Standard meals were provided at 0600 and 2200. GH was measured every 5 10 min for 24 h (0800-0800). Daytime (0800-2200) integrated GH concentrations were approximately 150-160% greater during SEB and DEB than during C: 1,282 +/- 345, 3,192 +/- 669, and 3,389 +/- 991 min.microgram.l-1 for C, SEB, and DEB, respectively [SEB > C (P < 0.06), DEB > C (P < 0.03)]. There were no differences in GH release during sleep (2300-0700). Deconvolution analysis revealed that the increase in 14-h integrated GH concentration on DEB was accounted for by an increase in the mass of GH secreted per pulse (per liter of distribution volume, lv): 7.0 +/- 2.9 and 15.9 +/- 2.6 micrograms/lv for C and DEB, respectively (P < 0.01). Comparison of 1.5-h integrated GH concentrations on the SEB and DEB days (30 min exercise + 60 min recovery) revealed that, with each subsequent exercise bout, GH release apparently increased progressively, with a slightly greater increase on the DEB day [SEB vs. DEB: 497 +/- 162 vs. 407 +/- 166 (bout 1), 566 +/- 152 vs. 854 +/- 184 (bout 2), and 633 +/- 149 vs. 1,030 +/- 352 min.microgram.l-1 (bout 3), P < 0.05]. We conclude that the GH response to acute aerobic exercise is augmented with repeated bouts of exercise. PMID- 9375350 TI - A servo-controlled respiration system for inhalation studies in anesthetized animals. AB - To facilitate aerosol deposition experiments and aerosol exposures in anesthetized animals, a servo-controlled respiration system was developed and tested. The system induces ventilation by varying extrathoracic pressure in a whole body respiratory in which an intubated animal is placed. The pressure inside the whole body respirator is varied with a three-way servo-controlled spool valve connected to sources of positive and negative pressure. A computer based system detects respiratory flow and computes the controlling signal for the valve by using a proportional-integral-derivative algorithm, to achieve desired patterns of flow and volume vs. time. The system was used with dogs and found to accurately induce various single-breath breathing patterns involving constant flow inspirations and expirations as well as breath-hold periods. A similar system was used to induced repeated breaths with desired parameters for continuous exposure to particles and for ventilation of animals between experiments. PMID- 9375351 TI - Synchronous direct gradient layer and indirect room calorimetry. AB - A dual direct/indirect room-sized calorimeter is used at the Beltsville Human Nutrition Research Center to measure heat emission and energy expenditure in humans. Because the response times of a gradient layer direct calorimeter and an indirect calorimeter are not equivalent, the respective rate of heat emission and energy expenditure cannot be directly compared. A system of equations has been developed and tested that can correct the respective outputs of the direct gradient layer calorimeter and indirect calorimeter for delays due to the response times of the measurement systems. Performance tests using alcohol combustion to simulate a human subject indicate accurate measurements of heat production from indirect (99.9 +/- 0.4%), indirect corrected for response time (99.9 +/- 0.5%), direct (99.9 +/- 0.8%), and direct corrected for response time (99.9 +/- 0.8%) calorimetry systems. Results from 24-h measurements in 10 subjects indicate that corrected heat emission is equivalent to (99.8 +/- 2.0%) corrected energy expenditure. However, heat emission measured during sleep was significantly greater (14%) than energy expenditure, suggesting a change in the energy stored as heat in the body. This difference was reversed during the day. These results illustrate how the simultaneous measurement of heat emission and energy expenditure provides insights into heat regulation. PMID- 9375353 TI - Levels of PCDDs and PCDFs in farm cow's milk located near potential contaminant sources in Asturias (Spain). Comparison with levels found in control, rural farms and commercial pasteurized cow's milks. AB - Cows milk samples from 12 dairy farms in Spain and 23 samples of pasteurised cows milk were analysed for PCDD/F. Farms located in rural areas without specific dioxin sources (background levels) ranged from 1.3 to 2.47 pg TEQ/g fat basis. These values were slightly lower than those found in milk from the vicinity of potential dioxin emission sources (waste incinerator, chemical and metallurgical industry) and similar to milk near paper industry. The waste incinerator seems to be the emission source with the highest influence on the cows milk gathered in its vicinity. Thus, milk near the waste incinerator exhibited the highest PCDD/F levels, the highest PCDF/PCDD ratio and its congener PCDD pattern showed the highest difference respect to its control point. The PCDD/F average concentrations found in pasteurised commercial milk were lower than those found in raw milk and were comparable to those found in retail milk from other countries. PMID- 9375354 TI - Estimation of Koc values for deuterated benzene, toluene, and ethylbenzene, and application to ground water contamination studies. AB - Sorption partition coefficients between water and organic carbon (Koc) for deuterated benzene, toluene, and ethylbenzene have been estimated by measuring values of the octanol-water partition coefficient (Kow) and HPLC retention factors (k1), which correlate closely to values of Koc. Measured values of log Kow for non-deuterated and deuterated toluene are 2.77 (+/- 0.02) and 2.78 (+/- 0.04), respectively, indicating that within experimental error, log Koc for deuterated and non-deuterated toluene are the same. The HPLC method provides greater precision, and yields values of delta log Koc (= log Koc [deuterated]-log Koc [non-deuterated]) of -0.021 (+/- 0.001) for benzene, -0.028 (+/- 0.002) for toluene, and -0.035 (+/- 0.003) for ethylbenzene. The small values of delta log Koc demonstrates that deuterated compounds are excellent tracers for the hydrologic behavior of ground water contaminants. PMID- 9375352 TI - Organochlorine pesticides, polychlorinated biphenyls, polychlorinated dibenzo-p dioxins and dibenzofurans in human adipose tissue from western Kyungnam, Korea. AB - Hexachlorocyclohexanes (HCHs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) were determined in human adipose tissue samples collected from western Kyungnam, Korea. The residue levels of organochlorine compounds were in the order of DDTs followed by PCBs > HCHs > HCB > PCDDs/DFs. The mean concentrations of 2,3,7,8-TeCDD in male and female tissues were 2.8 and 1.7 pg.g-1 on lipid weight basis, respectively. No significant difference was found in the residue levels of PCDDs/DFs between sexes. In contrast, PCBs and DDTs showed a significant difference between sexes. Unlike the age trend observed for HCHs, PCBs and DDTs, PCDDs/DFs revealed a constant or rather decreasing pattern with increasing age. This is the first report on PCDDs/DFs contamination in human adipose tissue from Korea. Organochlorine concentrations in human adipose tissues from western Kyungnam were generally much lower than those of other countries. PMID- 9375355 TI - Comparative heavy metal biosorption study of brewery yeast and Myxococcus xanthus biomass. AB - The biosorption for La2+, Co2+, Mn2+, UO2(2+), Pb2+, Ag+, Zn2+, Cd2+ and Cr2+ by wet and dry biomass form Myxococcus xanthus obtained from laboratory cultures and Saccharomyces cerevisiae from the brewing industry has been studied. M. xanthus biomass was found to be the most efficient biosorbent for all of the metals assayed. However, due to the fact that S. cerevisiae is a low cost residual by product from the brewing industry, and at the same time yields good levels of biosorption, it is considered in this work to be of great interest for use as a detoxifier of heavy metals contaminated waters. In addition, the use of sodium carbonate as a desorbent agent is discussed where it was possible to recover up to 94,53% of UO2(2+) by both M. xanthus and S. cerevisiae biomass. PMID- 9375356 TI - Effect of pituitary adenylate cyclase-activating polypeptide on exocrine and endocrine secretion in the ovine pancreas. AB - The role of pituitary adenylate cyclase-activating polypeptide (PACAP) in the regulation of exocrine and endocrine pancreas was investigated in conscious sheep. Intravenous infusions of PACAP-27 and PACAP-38 (1, 3, and 10 pmol/kg/min) for 10 min during phase II of the duodenal migrating myoelectric complex accelerated pancreatic protein and amylase outputs dose-dependently. The responses in enzyme secretion to both PACAPs at the highest doses were inhibited significantly by atropine infusion (14.4 nmol/kg/min). Vasoactive intestinal polypeptide (VIP) at 3 pmol/kg/min significantly accelerated protein but not amylase outputs, although the response to the highest dose was not significantly influenced by atropine. PACAP-27 and VIP increased pancreatic juice flow and bicarbonate output dose-dependently; however, the responses to the highest dose were not altered significantly by atropine. On the other hand, intravenous injection of PACAP-38 (100 pmol/kg) did not influence basal plasma concentration of insulin, glucagon, and glucose. Moreover, PACAP-38 (1-100 pmol/kg) altered neither pancreatic endocrine response to intravenous infusion of glucose (20 mumol/kg/min) not that to n-butyric acid (33 mumol/kg/min). These results suggest that PACAP contributes to the regulation of exocrine secretion of the ovine pancreas but not to endocrine secretion. PACAP appears to accelerate pancreatic enzyme secretion mostly via the cholinergic nerves. PMID- 9375357 TI - Up-regulation of estrogen receptor mRNA and estrogen receptor activity by estradiol in liver of rainbow trout and other teleostean fish. AB - Injection of estradiol (E2) into immature rainbow trout resulted in the induction of the hepatic vitellogenin gene mediated by the nuclear estrogen receptor (ER). Liver ER mRNA rose markedly on E2 treatment in three groups of trout kept at different temperatures. Only in the group kept at 4 degrees C did the total cellular ER, as measured by [3H]estradiol-binding activity in nuclear and cytosol fractions, parallel the ER mRNA level. In fish kept at 9 degrees C and 15 degrees C, the ratio of total ER activity to ER mRNA fell during chronic E2 treatment, probably reflecting translational of post-translational control mechanisms. Upregulation of ER mRNA also occurred in sea raven, sculpin, winter flounder, and Atlantic salmon after E2 treatment. Intrahepatic ER activity rose proportionately in Atlantic salmon kept at 6-9 degrees C but not in sea raven, sculpin, or flounder. We conclude that the regulation of ER expression in teleosts is complex and includes transcriptional, translational, and post-translational elements and is influenced by environmental temperature. PMID- 9375358 TI - Trimethadione as a probe drug to estimate hepatic oxidizing capacity in humans. AB - Trimethadione (TMO) has the properties required of probe drugs for the evaluation of hepatic drug-oxidizing capacity in humans in vivo. TMO is demethylated to dimethadione (DMO), its only metabolite, in the liver after oral administration. Involvement of two cytochrome P450's--CYP2C9 and 3A4--in TMO metabolism has been seen in humans, but involvement of 1A2 is not clearly established. In humans with various types of liver disease and hepatectomy, the serum DMO/TMO ratios, which were measured on blood samples obtained by a single collection 4 hr after oral administration of TMO, correlated well with the degree of hepatic damage. This finding suggests that TMO may be used as a probe drug in the rapid determination of the functional reserve mass of the liver as well as hepatic drug-oxidizing capacity in humans in vivo. PMID- 9375359 TI - Effect of vanadate on the activity of rat jejunal 6-phosphofructo-1-kinase. AB - The effect of sodium orthovanadate on the activity of 6-phosphofructo-1-kinase (PFK) in the epithelial cells of rat small intestine was investigated. Injection of vanadate (2.5 mg/rat) into rats at 2-day intervals per week for two consecutive weeks resulted in a significant decrease in the maximal activities and activity ratios (activity at 0.5 mM fructose-6-phosphate at pH 7.0/activity at pH 8.0 [v0.5/V]) of the partially purified PFK in rat jejunum. Also, the sensitivity of jejunal PFK to inhibition by ATP increased in rats treated with vanadate. The addition of 1 microM fructose-2,6-biphosphate and 50 microM AMP in the assays released the enzyme inhibition by ATP, and no significant difference was seen between vanadate-injected and control rats. Moreover, the extent of activation with 1 microM fructose-2,6-bisphosphate was significantly higher (79%) in vanadate-injected rats than in control rats (26%). The present results indicate that rat jejunal PFK is highly inhibited with vanadate in vivo. Therefore, although vanadate has been considered to be an insulin-like agent, because of its insulin-like effects on adipocytes and skeletal muscle, the present results may indicate that this behavior could not be applicable to normal rat tissues, because the effect of vanadate on jejunal PFK is clearly opposite that of insulin. PMID- 9375360 TI - Voltage-gated ionic channels in cultured rabbit articular chondrocytes. AB - The membrane properties of cultured cells of rabbit articular chondrocytes were studied using the whole-cell patch clamp technique. The average cell capacitance was 37.9 +/- 9.0 pF (n = 13), and the cell resting potential was -41.0 +/- 7.0 mV (n = 11). We were unable to induce an action potential by applying a depolarizing current. Upon step depolarization, under voltage clamp conditions, one kind of inward and two kinds of outward currents were elicited. The inward current was initially observed at around -30 mV, peaked at 0 mV, and reversed at around +90 mV. Tetrodotoxin (TTX; 1 microM) was shown to completely block this inward current. At steady state, the inward current was half-inactivated at -51 mV, with a slope factor of 6.3 mV. Two outward currents were determined from measurements of activation threshold, reversal potential, and pharmacological responses. One was observed at around -30 mV, and its amplitude increased with membrane depolarization. Extracellularly applied 4-aminopyridine (4 AP) (1 mM) and tetraethyl ammonium chloride (TEA) (5 mM) blocked this current. The other outward current was observed at around +10 mV, and its direction reversed at a potential close to that predicted by the Nernst equation for a Cl- selective channel. This current fluctuated markedly, and the fluctuation did not decline throughout the 100 ms of the step pulse. Extracellularly applied 4-acetamido-4' isothiocyanostilbenezene-2,2-disulfonic acid (SITS) (0.25 mM) blocked this current, but the same dose of 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) had little effect. These results suggest the presence of TTX-sensitive Na+, 4-AP- and TEA-sensitive K+, and SITS-sensitive Cl- channels in rabbit articular chondrocyte membrane. The functional significance of these channels is discussed. PMID- 9375361 TI - Identification of a functional Gs protein in Euglena gracilis. AB - We found a Gs protein coupled to adenylyl cyclase in a free-living protist, Euglena gracilis. This Gs protein of approximately 42 kDa is substrate for cholera toxin and is recognized by an antibody against the C-terminal decapeptide of Gs. Furthermore, this protein is coupled to adenylyl cyclase, as shown by: (a) the activation of the enzyme by GTP-analogues and (b) the effect of cholera toxin on cAMP accumulation in intact cells and the continuous activation of adenylyl cyclase activity in membranes. These data indicate that the Gs-adenylyl cyclase coupled system is already apparent in the protist kingdom. PMID- 9375362 TI - Circadian regulation of Fos-like expression in the brain of the blow fly Calliphora vicina. AB - Expression of Fos-like immunoreactivity (FOS-lir) was examined in the brains of the blow fly Calliphora vicina for evidence of circadian regulation by photic stimuli. Fos-lir in various parts of the brain was investigated as a function of light and time of day. Immunohistochemistry demonstrated that photic stimuli have an inductive effect on c-fos expression in the various parts of the brain, but only in the neurons of the pars intercerebralis did the clear photic induction of c-fos expression occur at times when light was capable of phase-shifting circadian locomotor activity rhythms. This suggests that the c-fos gene may play a role in the photic pathway for circadian entrainment and that these neurons may be involved in the transduction of photic signals. Whether changes in c-fos expression are essential components of this pathway remains to be determined. PMID- 9375363 TI - Characterisation of the effects of cadmium on the release of calcium and on the activity of some enzymes from neonatal mouse calvaria in culture. AB - Exposure to cadmium (Cd) causes skeletal impairments, such as osteoporosis and osteomalacia, in many mammalian species, including humans. There is, however, some controversy about the mechanism of action of these Cd-induced skeletal effects, although both a direct influence on bone cells and effects that are secondary to renal damage caused by the metal have been demonstrated. In the present study, we cultured calvarial bones from neonatal mice and exposed them to Cd to study the effects of the metal on calcium release and on the activity of some enzymes of importance for bone resorption and bone formation. Cd dose dependently stimulated calcium release from the bones. Maximal release was noted at Cd concentrations of 0.4-0.8 microM, which was similar to the level of release in the presence of maximal stimulatory concentrations of parathyroid hormone (10 nM) and prostaglandin E2 (10 microM). Cykloheximide (1 microM) inhibited calcium release elicited by Cd, prostaglandin E2 and parathyroid hormone. Cd-induced calcium release was linearly increased from 24 to 72 hr of culture. Production of prostaglandin E2 by the bone specimens was dose-dependently stimulated by Cd and inhibited by 1 microM indomethacin. Cd-induced calcium release was inhibited by acetazolamide (100 microM), indomethacin (1 microM) and ibuprofen (10 microM). Prostaglandin E2-stimulated calcium release was not inhibited by indomethacin. Exposure to 32 microM Cd, present during a 48-hr incubation period, significantly decreased prostaglandin E2-stimulated calcium release from 38.9% to 29.8%. Calcium release induced by parathyroid hormone was more sensitive to inhibition by the metal (i.e., Cd concentrations of 0.2 and 32 microM decreased the release from 37.7% to 31% and 19%, respectively). Cd present in the culture medium during a 48-hr incubation dose-dependently inhibited the activity of alkaline phosphatase and tartrate-resistant acid phosphatase in the bones but did not influence the activity of carbonic anhydrase. We conclude that Cd has a direct stimulatory effect on bone resorption, and this effect is dependent on prostaglandin production and also on protein synthesis. On the other hand, Cd also has an inhibitory effect on bone resorption (i.e., resorption is inhibited by higher concentrations of the metal). Moreover, Cd may impair bone formation by impeding the activity of alkaline phosphatase. PMID- 9375364 TI - Plasma and urine levels of C18, C19 and C21 steroids in an asynchronous fish, the tilapia Oreochromis mossambicus (Teleostei, Cichlidae). AB - Female and male tilapia, Oreochromis mossambicus, were treated with luteinizing hormone-releasing hormone analogue (LH-RHa) and pimozide (PIM) or with human chorionic gonadotropin (hCG) to stimulate gonadal development and sexual maturation. Plasma (both sexes) and urine (males) samples were collected periodically for steroid analysis by radioimmunoassay. Plasma levels of estradiol 17 beta (3-6 ng/ml) and testosterone, higher in female (up to 25 ng/ml) than in male (6-13 ng/ml; P < 0.05), were in the range of those established in other tilapia species. Plasma levels of the established teleost oocyte maturation inducing steroids (MIS), that is 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (17,20 beta-P) and 17 alpha,20 beta, 21-trihydroxy-4-pregnen-3-one (17,20 beta,21 P) were low (1-9 ng/ml) and were not different between treated and control fishes at 8, 12, 16, 24, 48, 72 and 96 hr after injection. Furthermore, in male O. mossambicus, 17,20 beta,21-P was undetectable. Plasma levels of 3 alpha,17 alpha,21-trihydroxy-5 beta-pregnan-20-one (3,17,21-P-5 beta) were very high in both sexes (up to 700 ng/ ml), mostly in hormone-treated groups, whose levels were higher than controls (P < 0.05). Urine levels of conjugated 17,20 beta,21-P (glucuronides and sulphates) were not detectable, but those of 17, 20 beta-P (up to 25 ng/ ml) and 3,17,21-P-5 beta (up to 1 microgram/ml) were higher than free 17,20 beta-P and 3,17,21-P-5 beta measured in the plasma of the same animals (P < 0.05). Both LH-RHa + PIM and hCG induced sexual maturation of O. mossambicus (histological data); nevertheless, during that period all measured steroids, either in plasma or urine, almost did not fluctuate. Thus, this study does not make any comment about the MIS of tilapia. Nevertheless, the high levels of conjugated 3,17,21-P-5 beta and 17,20 beta-P in urine suggest a probable pheromone role for these steroids in this species. PMID- 9375365 TI - Schistosoma mansoni: effect of recombinant tumor necrosis factor alpha on fecundity and [14C]-tyrosine uptake in females maintained in vitro. AB - It has been reported that recombinant tumor necrosis factor alpha (rTNF alpha) stimulates egg-laying in Schistosoma mansoni females. Because tyrosine requirement is increased in female undergoing sexual maturation in preparation for oogenesis and tyrosine is a major component of eggshell protein, we wanted to determine whether females treated with rTNF alpha would also incorporate more tyrosine. Adult females were first treated with 10, 20 or 40 ng/ml rTNF alpha for 1, 3 or 6 hr in RPMI 1640 containing 10% fetal calf serum (FCS). Another two groups of females were each exposed either to males or to male excretory secretory (ES) products for 1 hr. They were then exposed to 20 microCi/ml-1 [14C] tyrosine for 1 hr in RPMI 1640 containing 10% FCS. All females were incubated individually unless indicated otherwise. Females incorporated more tyrosine after exposure to males or their ES products. They incorporated significantly more tyrosine when treated with rTNF alpha for 1 hr; the increased uptake correlated with increasing amounts of rTNF alpha used. Although after a 3-hr treatment with 10 ng/ml rTNF alpha females incorporated slightly more tyrosine than controls, increasing amounts of rTNF alpha had an adverse effect. Females treated with rTNF alpha for 6 hr incorporated less tyrosine than controls and those treated for 1 hr. SDS-PAGE and fluorography did not reveal any differences in polypeptide profiles of untreated and rTNF alpha-treated females. These unexpected results led us to study the effect of rTNF alpha on fecundity in females. Contrary to the published report, we observed a sharp decline in egg-laying in females when exposed to increasing concentrations of rTNF alpha in vitro. PMID- 9375366 TI - Cell cycle control in isoproterenol-induced murine salivary acinar cell proliferation. AB - The eukaryotic cell cycle is a summary of a complex network of signal transduction pathways resulting in both DNA replication and cell division. Cyclin dependent kinases (CDKs) control the cell cycle in all eukaryotes, whereas other proteins, known as cyclins, act as their regulatory subunits. Chronic injection with isoproterenol (ISO) can induce acinar cell proliferation in rodent salivary glands. Cyclins and CDK proteins from control and ISO-treated murine parotid acinar cells were detected by using Western blotting techniques. By comparing the expression of these cell cycle regulatory kinases in the parotid acinar cell transition from a quiescent state to a hypertrophic state, we found rapid increases in the protein levels of all CDKs, cyclin D and proliferating cell nuclear antigen (PCNA). The highest protein levels for CDKs and cyclins appeared at about 72 hr of ISO stimulation and were coincident with the highest rate of increase in gland wet weight. After 72 hr, the increase of both cell cycle protein and gland wet weight began to subside. By using a co-immunoprecipitation method, the following cell cycle regulators (CDK-cyclin complexes) were detected, CDK4-cyclin D, CDK2-cyclin E, CDK2-cyclin A, and cdc2-cyclin B, along with an increase in kinase activity over control untreated animals. Additionally, we detected significant decreases in the newly isolated CDK inhibitor (CKI) p27kip but not Wee 1 kinase. The increased levels of CKI correlated with a decrease in kinase activity of CDK/cyclin complexes by 144 hr of chronic isoproterenol treatment. Our data suggest that the holoenzymes for cell cycle control (cyclin CDK complexes) function as a final regulatory mechanism leading to salivary gland acinar cell proliferation. The gradual decline in protein levels of the CDKs and cyclins after 3 days of chronic treatment further indicates that ISO-induced proliferation of parotid acinar cells is self-limiting and non-tumorigenic. PMID- 9375368 TI - Observation of periparturitional behaviour in wild Yakushima macaques (Macaca fuscata yakui). PMID- 9375367 TI - Inter- and intraspecific variation in the diets of sympatric siamang (Hylobates syndactylus) and lar gibbons (Hylobates lar). AB - Studies of the siamang (Hylobates syndactylus continentis) and the lar gibbon (Hylobates lar lar) where they co-occur in mainland Asia have demonstrated interspecific dietary segregation based on body size and have suggested that observed levels of frugivory represent metabolically based maxima for these species. I studied sympatric groups of siamang (H. s. syndactylus) and lar gibbons (H. l. vestitus) at Ketambe in northern Sumatra (Indonesia) in order to assess the magnitude of within- and between-species variation in diets. The insular subspecies are considerably more frugivorous (60-70% of feeding time) than mainland conspecifics (35-50%). This is primarily because Sumatran hylobatids spend about twice as much time (approx. 45% of feeding) eating fig fruits (Ficus spp., Moraceae). A higher density of figs at Ketambe (compared to Kuala Lompat) may account for this behavioral difference. Enhanced frugivory has been achieved at the expense of folivory, which is much reduced in Sumatra- especially in H. lar (4% of diet)- and is limited almost entirely to immature foliage. The expected decline in protein intake resulting from diminished folivory in Sumatra may be counterbalanced by observed increases in insectivory, which is especially pronounced in lar gibbons. Interspecific dietary segregation emerges most clearly in how individuals of each species supplement their similarly fig-dominated diets. Siamang rely more on immature foliage--primarily from lianas, which generate young leaves more reliably and abundantly than trees do. Conversely, lar gibbons exploit the pulpy fruit of trees and lianas more heavily than siamang do. This general pattern occurs where the two species coexist in Malaysia, thereby suggesting a substantive interspecific difference that is somewhat greater in the insular populations. PMID- 9375369 TI - Breeding seasonality affects the association between dominance and reproductive success in non-human male primates. PMID- 9375370 TI - No directionality of short tandem repeat evolution at the HPRT locus in catarrhine primates. PMID- 9375372 TI - Focal adhesion kinase. AB - Focal adhesion kinase (FAK) is a member of a growing family of non-receptor protein tyrosine kinases. Though originally identified as a putative substrate for the oncogenic tyrosine kinase pp60v-src, it is now well-established that FAK tyrosine phosphorylation is induced by adhesion of cell surface integrins to extracellular matrix and by a variety of other extracellular factors including the ligands for receptor tyrosine kinases and for seven transmembrane domain G protein-coupled receptors. FAK can associate with multiple cellular components including other focal adhesion-associated proteins and signalling molecules. FAK is localized to focal adhesions and is centrally implicated in the regulation of cell motility and adhesion. Knocking out the FAK gene in mice prevents normal embryonic development and is associated with loss of mesenchymal cell motility. Recent findings further suggest novel tissue-specific functions for FAK, particularly in the brain. These findings implicate FAK in the aberrant migration of cells in a variety of diseases and suggest that FAK may be a novel target for therapeutic strategies. PMID- 9375371 TI - Does female rank or age affect mate choice in free-ranging rhesus macaques? PMID- 9375373 TI - DNA-dependent protein kinase. AB - DNA-dependent protein kinase (DNA-PK) is a nuclear protein serine/threonine kinase that is activated by DNA double strand breaks (DSBs). It is a component of the DNA DSB repair apparatus, and cells deficient in DNA-PK are hypersensitive to ionising radiation and radio-mimetic drugs. In addition, DNA-PK is required to generate the antigen binding sites of T-cell receptor and immunoglobulin molecules, and the phenotype of the severe combined immunodeficient (scid) mouse is due to a DNA-PK deficiency. Recent data suggest that DNA-PK may also have roles in controlling transcription, apoptosis, and the length of telomeric chromosomal ends. Finally, DNA-PK is related to other proteins involved in DNA damage detection, including the protein defective in the human neurodegenerative and cancer predisposition syndrome ataxia-telangiectasia. Studies on DNA-PK should provide a better understanding of degenerative disease and cancer, and may lead to improved therapies for these conditions. PMID- 9375374 TI - Fibronectin. AB - Fibronectin is a glycoprotein consisting of repeating units of amino acids, which form domains that enable the molecule to interact with a variety of cells through both integrin and non-integrin receptors. It is encoded by a single gene, but alternative splicing of pre-mRNA allows formation of multiple isoforms that have critical roles in cell adhesion, migration and proliferation. The essential nature of fibronectin in development has clearly been demonstrated in a "knock out" mouse model in which early lethality occurs. Fibronectin influences diverse processes including inflammation, wound repair, malignant metastasis, microorganism attachment and thrombosis. Researchers are currently developing tools, including synthetic peptides based on specific fibronectin regions. These molecules have been shown to alter processes such as lymphocyte binding in synovial tissue of rheumatoid arthritis, coronary arteriopathy in animal models of cardiac transplantation, and platelet aggregation in patients, and are thus providing important new therapeutic possibilities. PMID- 9375375 TI - PKR--a protein kinase regulated by double-stranded RNA. AB - The RNA-regulated protein kinase, (PKR) is an interferon-inducible enzyme of widespread occurrence in eukaryotic organisms. This serine/threonine-specific protein kinase is activated by double-stranded RNA by a mechanism involving autophosphorylation. Once activated, the enzyme phosphorylates the alpha subunit of protein synthesis initiation factor eIF2, thereby inhibiting translation. Recent evidence suggests that there may be additional substrates, and that signal transduction and gene transcription pathways also may be regulated by the protein kinase. As well as being important in mediating the antiviral effects of interferons, PKR is implicated in regulating cell proliferation in uninfected cells and may have a tumour suppressor function under normal conditions. Studies using cell lines expressing inactive mutants of PKR and mice with homozygous disruptions of the PKR gene are leading to greater insights into the biological significance of this enzyme. PMID- 9375376 TI - Neuronal Cdc2-like kinases: neuron-specific forms of Cdk5. AB - Neuronal Cdc2-like kinase, Nclk, is a heterodimer of a Cdk5 catalytic subunit and a 25 kDa regulatory subunit derived proteolytically from a neuron- and central nervous system-specific 35 kDa protein. The regulatory subunit is mandatory for kinase activity, hence it is designated the neuronal Cdk5 activator, p25/p35nck5a. Nclk has been suggested to play a regulatory role in neuro cytoskeleton dynamics and in neuronal differentiation. In addition to the activation by Nck5a, Cdk5 is regulated by other mechanisms including additional activator proteins and inhibition by phosphorylation of specific amino acid residues. While Nclk shares common catalytic and regulatory properties with other members of the cdc2-like kinase family, it also displays unique characteristics that may be important for its neuronal functions. PMID- 9375377 TI - Identification of a novel keratin epitope: evidence for association between non helical sub-domains L12 during filament assembly. AB - Keratin filaments in simple epithelial cells are heteropolymers of keratin 8 (K8) and keratin 18 (K18) polypeptides. The assembly of these polypeptides into intermediate filaments is a complex multi-stage phenomenon that involves several levels of associations. These molecular associations are not very well characterized. Monoclonal antibodies (MAbs) with defined specificities can be used to probe these associations and to isolate various intermediates in the assembly pathway. Here we describe the specificity of a MAb LE65 that has been widely used in keratin expression studies. We report that the MAb LE65 does not recognize individual keratin polypeptides but it instead reacts with a complex of K8 with K18. The MAb also did not react with complexes of K8 or K18 with other keratins. By allowing the antibody to react with complexes reconstituted from keratin fragments plus the complementary keratin, we have mapped the MAb LE65 epitope on the L12 sub-domains of K18, residues 214-231, and K8, residues 234 265, which must associate together to achieve antibody binding. These results suggest that the non-helical linkers, L12, of complementary keratins associate directly during filament assembly. This would explain why microinjection of MAb LE65 has been shown to disrupt keratin filaments. Furthermore, it may also help to explain the mechanism of filament disruption in some skin blistering syndromes induced by spontaneous mutations in the L12 region. PMID- 9375378 TI - Characterization of multiple acid phosphatases in bovine liver cytosol and lysosome. Inactivation of cytosolic enzymes by disulfides and its redox regulation by thioltransferase. AB - Cytosolic and lysosomal acid phosphatases have the ability to hydrolyze orthophosphoric monoesters below pH 5-6. However, it is thought they may have different intracellular roles. To clarify their properties, substrate specificity, inhibitor sensitivity and the modulation of enzyme by redox conditions were determined using bovine liver enzymes. DEAE-cellulose chromatography following (NH4)2SO4 fractionation revealed three forms of cytosolic acid phosphatases as in the KCl gradient (0-500 mM). After Sephadex G 75 gel filtration, the enzymes appeared as single bands on SDS-polyacrylamide gel electrophoresis (SDS-PAGE). Their activities for D-erythrose 4-phosphate co purified with p-nitrophenylphosphatase activities in all steps. In contrast the lysosomal enzyme was purified by Octyl-Sepharose column chromatography after n butanol treatment, (NH4)2SO4 fractionation, Bio gel P-200 gel filtration and DE 52 chromatography. The relative molecular masses (M(r)) determined by SDS-PAGE indicated that M(r) of the cytosolic enzymes (16,000) was less that of lysosomal enzyme (160,000). The cytosolic enzymes were active against sugar phosphates and were inhibited by 1 mM Cu2+. In addition, the cytosolic enzymes were inactivated by 5 mM oxidized glutathione and protected by 10 mM reduced glutathione (in the presence or absence of thioltransferase), suggesting that sensitive cysteinyl residue(s) existed. The lysosomal enzyme was active against various substrates and was strongly inhibited by 1 mM Cu2+ and 2 mM fluoride. The results presented here suggest that cytosolic enzymes have different properties from those of lysosomal enzyme with respect to substrates, inhibitors and regulation of activity. PMID- 9375379 TI - Human neutrophils do not degrade major basement membrane components during chemotactic migration. AB - At sites of inflammation, circulating neutrophils (PMNs) migrate